Publication date: Available online 6 May 2017
Source:Biochimica et Biophysica Acta (BBA) - Gene Regulatory Mechanisms
Author(s): Kyung-Won Min, Sylvia Davila, Richard W. Zealy, Lawson T. Lloyd, In Young Lee, Rumi Lee, Kyung Hye Roh, Ahjin Jung, Jacek Jemielity, Eui-Ju Choi, Jeong Ho Chang, Je-Hyun Yoon
Post-transcriptional gene regulation is an important step in eukaryotic gene expression. The last step to govern production of nascent peptides is during the process of mRNA translation. mRNA translation is controlled by many translation initiation factors that are susceptible to post-translational modifications. Here we report that one of the translation initiation factors, eIF4E, is phosphorylated by Mammalian Ste20-like kinase (MST1). Upon phosphorylation, eIF4E weakly interacts with the 5′ CAP to inhibit mRNA translation. Simultaneously, active polyribosome is more associated with long noncoding RNAs (lncRNAs). Moreover, linc00689-derived a micropeptide, STORM (Stress- and TNF-α-activated ORF Micropeptide), is induced by TNF-α-induced and MST1-mediated eIF4E phosphorylation exhibits molecular mimicry of SRP19 and, thus, competes for 7SL RNA. Our findings have uncovered a novel function of MST1 in mRNA and lncRNA translation by direct phosphorylation of eIF4E. This novel signaling pathway will provide new platforms for mRNA regulation of mRNA translation via post-translational protein modification.
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Σάββατο 6 Μαΐου 2017
Subcellular distribution of RAD23B controls XPC degradation and DNA damage repair in response to chemotherapy drugs
Publication date: August 2017
Source:Cellular Signalling, Volume 36
Author(s): Xue You, Weiwei Guo, Lin Wang, Yongfan Hou, Huanhuan Zhang, Yi Pan, Ruomei Han, Meiqin Huang, Lujian Liao, Yan Chen
The RAD23B-XPC complex in the nucleus plays a key role in the initial damage recognition during global genome nucleotide excision repair (NER). Within the complex, XPC, a product of Xeroderma pigmentosum C, recognizes and interacts with the unpaired bases in the undamaged DNA strand, while RAD23B stabilizes XPC. However, how RAD23B is regulated by other factors is not well known. We report here a mode of spatial regulation of RAD23B that controls XPC stability and DNA damage repair. We first identified that RAD23B was able to directly associate with PAQR3, a newly-discovered tumor suppressor implicated in many types of human cancers. PAQR3 reduced the protein level of XPC, together with accelerated degradation and enhanced polyubiquitination of XPC. Mechanistically, PAQR3 reduces nucleic distribution of RAD23B by tethering it to the Golgi apparatus, thus diminishing the amount of RAD23B proteins available to interact with XPC in the nucleus. The viability of gastric cancer cells upon treatment with chemotherapy drugs including etoposide, cisplatin and doxorubicin was reduced by PAQR3 overexpression, but enhanced by PAQR3 knockdown. The degree of DNA damage induced by these drugs, as measured by immunoblotting with γ-H2AX, was elevated by PAQR3 overexpression and lessened by PAQR3 knockdown. Furthermore, a synthetic peptide comprising the N-terminus of PAQR3 was able to recapitulate the activity of PAQR3 in reducing XPC stability and enhancing chemotherapy drug-induced DNA damage. In conclusion, our study reveals that RAD23B is controlled by subcellular compartmentation, thus affecting XPC-mediated DNA damage repair in cancer cells.
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Source:Cellular Signalling, Volume 36
Author(s): Xue You, Weiwei Guo, Lin Wang, Yongfan Hou, Huanhuan Zhang, Yi Pan, Ruomei Han, Meiqin Huang, Lujian Liao, Yan Chen
The RAD23B-XPC complex in the nucleus plays a key role in the initial damage recognition during global genome nucleotide excision repair (NER). Within the complex, XPC, a product of Xeroderma pigmentosum C, recognizes and interacts with the unpaired bases in the undamaged DNA strand, while RAD23B stabilizes XPC. However, how RAD23B is regulated by other factors is not well known. We report here a mode of spatial regulation of RAD23B that controls XPC stability and DNA damage repair. We first identified that RAD23B was able to directly associate with PAQR3, a newly-discovered tumor suppressor implicated in many types of human cancers. PAQR3 reduced the protein level of XPC, together with accelerated degradation and enhanced polyubiquitination of XPC. Mechanistically, PAQR3 reduces nucleic distribution of RAD23B by tethering it to the Golgi apparatus, thus diminishing the amount of RAD23B proteins available to interact with XPC in the nucleus. The viability of gastric cancer cells upon treatment with chemotherapy drugs including etoposide, cisplatin and doxorubicin was reduced by PAQR3 overexpression, but enhanced by PAQR3 knockdown. The degree of DNA damage induced by these drugs, as measured by immunoblotting with γ-H2AX, was elevated by PAQR3 overexpression and lessened by PAQR3 knockdown. Furthermore, a synthetic peptide comprising the N-terminus of PAQR3 was able to recapitulate the activity of PAQR3 in reducing XPC stability and enhancing chemotherapy drug-induced DNA damage. In conclusion, our study reveals that RAD23B is controlled by subcellular compartmentation, thus affecting XPC-mediated DNA damage repair in cancer cells.
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The mammalian STE20-like kinase 1 (MST1) is a substrate for the apoptosis inhibiting protein kinase CK2
Publication date: Available online 6 May 2017
Source:Cellular Signalling
Author(s): Christina Servas, Sandra Kiehlmeier, Julia Hach, Rebecca Gross, Claudia Götz, Mathias Montenarh
Apoptosis and the response to cell stress are evolutionary highly conserved mechanisms. Both processes require strict regulation, which is often performed by protein kinases. The mammalian Sterile 20-like kinase 1 (MST1) is a pro-apoptotic protein kinase, which is activated and cleaved by caspases upon the induction of cell stress. Being a phosphoprotein itself, the activity of MST1 is regulated by phosphorylation. Protein kinase CK2 is an anti-apoptotic protein kinase which seems to be involved in the regulation of many different cellular processes including apoptosis. There is increasing evidence that the cleavage of many substrates by caspases is regulated by phosphorylation in the close vicinity of the caspase cleavage sites. One of these kinases, implicated in the phosphorylation of caspase substrates, is protein kinase CK2. Here, we report that serine 320 of the MST1 protein is a novel phosphorylation site for the anti-apoptotic protein kinase CK2. Although serine 320 is in close vicinity to the caspase 3 cleavage site, caspase 3 cleavage of MST1 is not affected by CK2 phosphorylation. Using biochemical approaches, we were able to show that MST1 co-localizes with the CK2 subunits in the pancreatic β-cell line INS-1 and that full-length MST1 and the activated N-terminal fragment of MST1 both interacted with the CK2 subunits in vitro and in vivo. MST1 is a basophilic kinase whereas CK2 is an acidophilic kinase. Thus, binding of these two kinases in the cytosol and in the nucleus opens the door to the phosphorylation of a variety of new substrates.
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Source:Cellular Signalling
Author(s): Christina Servas, Sandra Kiehlmeier, Julia Hach, Rebecca Gross, Claudia Götz, Mathias Montenarh
Apoptosis and the response to cell stress are evolutionary highly conserved mechanisms. Both processes require strict regulation, which is often performed by protein kinases. The mammalian Sterile 20-like kinase 1 (MST1) is a pro-apoptotic protein kinase, which is activated and cleaved by caspases upon the induction of cell stress. Being a phosphoprotein itself, the activity of MST1 is regulated by phosphorylation. Protein kinase CK2 is an anti-apoptotic protein kinase which seems to be involved in the regulation of many different cellular processes including apoptosis. There is increasing evidence that the cleavage of many substrates by caspases is regulated by phosphorylation in the close vicinity of the caspase cleavage sites. One of these kinases, implicated in the phosphorylation of caspase substrates, is protein kinase CK2. Here, we report that serine 320 of the MST1 protein is a novel phosphorylation site for the anti-apoptotic protein kinase CK2. Although serine 320 is in close vicinity to the caspase 3 cleavage site, caspase 3 cleavage of MST1 is not affected by CK2 phosphorylation. Using biochemical approaches, we were able to show that MST1 co-localizes with the CK2 subunits in the pancreatic β-cell line INS-1 and that full-length MST1 and the activated N-terminal fragment of MST1 both interacted with the CK2 subunits in vitro and in vivo. MST1 is a basophilic kinase whereas CK2 is an acidophilic kinase. Thus, binding of these two kinases in the cytosol and in the nucleus opens the door to the phosphorylation of a variety of new substrates.
Graphical abstract
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Editorial Board and Publication Information
Publication date: 24 May 2017
Source:Journal of Biomechanics, Volume 57
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Source:Journal of Biomechanics, Volume 57
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Prader-Willi syndrome
Prader-Willi syndrome: A syndrome characterized by severe hypotonia (floppiness), poor suck and feeding problems in early infancy followed later in infancy by excessive eating that, if unchecked, leads gradually to huge obesity. All children with Prader-Willi syndrome (PWS) show developmental delay and mild-to-moderate mental retardation with multiple learning disabilities. Hypogonadism is present in both females (with small labia minora and clitoris) and males (with underdeveloped scrotum and nondescent of the testes). Short stature and small hands and feet are common.
The basic cause of PWS is extraordinary. It is due to absence of the paternally contributed region on chromosome 15q11-q13. What is missing is not just any chromosome 15q11-13 region but specifically that from the father. The child can have two copies of chromosome region 15q11-13 but, if both are from the mother (a phenomenon called maternal disomy), the child will still have PWS for lack of the region from the father.
Several of the genes in region 15q11-13 are subject to genomic imprinting. This explains why PWS results only when the paternally-contributed region 15q11-13 is absent. When the maternally-contributed region 15q11-13 is missing, the result is a different disease called Angelman syndrome.
There is currently no specific treatment or cure for PWS. Parents are advised to limit consumption of high-calorie foods, and to use techniques such as special education, speech therapy, and physical therapy to maximize the child's potential. Severe psychiatric illness is common in PWS adults. Those with psychotic illness have a double maternal copy of 15q11-13, suggesting that genes in this region are important in causing psychotic illness.
MedTerms (TM) is the Medical Dictionary of MedicineNet.com.
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An Interspecies Heart-to-Heart: Using Xenopus to Uncover the Genetic Basis of Congenital Heart Disease
Abstract
Purpose of Review
Given the enormous impact congenital heart disease has on child health, it is imperative that we improve our understanding of the disease mechanisms that underlie patient phenotypes and clinical outcomes. This review will outline the merits of using the frog model, Xenopus, as a tool to study human cardiac development and left-right patterning mechanisms associated with congenital heart disease.
Recent Findings
Patient-driven gene discovery continues to provide new insight into the mechanisms of congenital heart disease, and by extension, patient phenotypes and outcomes. By identifying gene variants in CHD patients, studies in Xenopus have elucidated the molecular mechanisms of how identified candidate genes affect cardiac development and left-right patterning, a process that has major impacts on cardiac morphogenesis. Xenopus is also a useful screening tool that helps define the biological relevance of identified patient mutations. Ongoing investigations continue to illuminate disease mechanisms using this organism.
Summary
Analyses in model organisms can help to elucidate the disease mechanisms underlying CHD patient phenotypes. Using Xenopus to disentangle the genotype-phenotype relationships of well-known and novel disease genes could enhance the ability of physicians to efficaciously treat patients and predict clinical outcomes, ultimately improving quality of life and survival rates of patients born with congenital heart disease.
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The Nonradiographic Axial Spondyloarthritis, the Radiographic Axial Spondyloarthritis, and Ankylosing Spondylitis: The Tangled Skein of Rheumatology
Since 1984 the diagnosis of ankylosing spondylitis (AS) has been based upon the modified New York (mNY) criteria with mandatory presence of radiographic sacroiliitis, without which the diagnosis is not tenable. However, it may take years or decades for radiographic sacroiliitis to develop delaying the diagnosis for long periods. It did not matter in the past because no effective treatment was available. However, with the availability of a highly effective treatment, namely, tumour necrosis factor-α inhibitors (TNFi), the issue of early diagnosis of AS acquired an urgency. The Assessment of SpondyloArthritis International Society (ASAS) classification criteria published in 2009 was a significant step towards this goal. These criteria described an early stage of the disease where sacroiliitis was demonstrable only on MRI but not on standard radiograph. Therefore, this stage of the disease was labelled “nonradiographic axial SpA” (nr-axSpA). But questions have been raised if, in search of early diagnosis, specificity was compromised. The Federal Drug Administration (FDA, USA) withheld approval for the use of TNFi in patients with nr-axSpA because of issues related to the specificity of these criteria. This review attempts to clarify some of these aspects of the nr-axSpA-AS relationship and also tries to answer the question whether ASAS classifiable radiographic axial spondyloarthritis (r-axSpA) term can be interchangeably used with the term AS.
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Tetrodotoxin for Moderate to Severe Cancer-Related Pain: A Multicentre, Randomized, Double-Blind, Placebo-Controlled, Parallel-Design Trial
Objective. This study evaluated subcutaneous injections of tetrodotoxin (TTX) for the treatment of moderate to severe, inadequately controlled cancer-related pain. Methods. Eligible patients were randomized to receive TTX (30?µg) or placebo subcutaneously twice daily for four consecutive days. Efficacy was assessed using pain and composite endpoints (including pain and quality of life measures), and safety was evaluated using standard measures. Results. 165 patients were enrolled at 19 sites in Canada, Australia, and New Zealand, with 149 patients in the primary analysis “intent-to-treat” population. The primary analysis supports a clinical benefit of TTX over placebo based on the pain endpoint alone with a clinically significant estimated effect size of 16.2% (). The value was nominally statistically significant after prespecified (Bonferroni Holm) adjustment for the two primary endpoints but not at the prespecified two-sided 5% level. The mean duration of analgesic response was 56.7 days (TTX) and 9.9 days (placebo). Most common adverse events were nausea, dizziness, and oral numbness or tingling and were generally mild to moderate and transient. Conclusions. Although underpowered, this study demonstrates a clinically important analgesic signal. TTX may provide clinically meaningful analgesia for patients who have persistent moderate to severe cancer pain despite best analgesic care. This clinical study is registered with ClinicalTrials.gov (NCT00725114).
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Helicobacter pylori from Peptic Ulcer Patients in Uganda Is Highly Resistant to Clarithromycin and Fluoroquinolones: Results of the GenoType HelicoDR Test Directly Applied on Stool
Background. Around 70–90% of peptic ulcer disease (PUD) is due to Helicobacter pylori and requires treatment with antimicrobials to which these bacteria are susceptible. Common H. pylori diagnostic tests do not provide drug susceptibility data. Using the GenoType HelicoDR PCR test designed for gastric biopsies for simultaneous detection of H. pylori and its resistance to clarithromycin (CLA)/fluoroquinolones (FLQ), we present evidence for stool as an optional test specimen and also provide data on prevalence of H. pylori resistance to CLA and FLQ in Uganda. Methods. Stool from 142 symptomatic PUD patients at three hospitals in Kampala was screened for H. pylori using a rapid antigen test. The GenoType HelicoDR test was run on all H. pylori antigen positives to determine PCR positivity and resistance to CLA/FLQ. Results. Thirty-one samples (22%) were H. pylori antigen positive, and 21 (68%) of these were H. pylori PCR positive. Six of the 21 (29%) were resistant to CLA and eight to FLQ (42%), while two gave invalid FLQ resistance results. Conclusion. Stool is a possible specimen for the GenoType HelicoDR test for rapid detection of H. pylori and drug resistance. In Uganda, Helicobacter pylori is highly resistant to CLA and FLQ.
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Polyurethane Nanofiber Membranes for Waste Water Treatment by Membrane Distillation
Self-sustained electrospun polyurethane nanofiber membranes were manufactured and tested on a direct-contact membrane distillation unit in an effort to find the optimum membrane thickness to maximize flux rate and minimize heat losses across the membrane. Also salt retention and flux at high salinities up to 100 g kg−1 were evaluated. Even though the complex structure of nanofiber layers has extreme specific surface and porosity, membrane performance was surprisingly predictable; the highest flux was achieved with the thinnest membranes and the best energy efficiency was achieved with the thickest membranes. All membranes had salt retention above 99%. Nanotechnology offers the potential to find modern solutions for desalination of waste waters, by introducing new materials with revolutionary properties, but new membranes must be developed according to the target application.
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Boi-ogi-to (TJ-20), a Kampo Formula, Suppresses the Inflammatory Bone Destruction and the Expression of Cytokines in the Synovia of Ankle Joints of Adjuvant Arthritic Rats
TJ-20 is a formula consisting of 6 herbs that has been used in the clinical treatment of rheumatoid arthritis (RA) in China and Japan for centuries. However, scientific evidence of the effects of TJ-20 has not been established. In the present study, we focused on the therapeutic effects and investigated the main function of TJ-20 on adjuvant arthritis (AA), an animal model of RA, which was induced with complete Freund’s adjuvant (CFA). TJ-20 was administered orally at 600 mg/kg once a day from 0, 7, and 10 days to 8 weeks after the CFA treatment. TJ-20 significantly ameliorated inflammatory progression and bone destruction in AA in a time-dependent manner. Furthermore, TJ-20 significantly reduced the increased changes in a number of macrophages and helper T cells. Moreover, TJ-20 suppressed the expression of TNF-α whereas it augmented the expression of IL-10 and attenuated Th1 cells responses in the synovia of the ankle joint. Therefore, TJ-20 regulated the expression of proinflammatory and anti-inflammatory cytokines in macrophages and Th1/Th2 balance in the synovia of ankle joints in AA rats. These results suggest the positive anti-inflammatory effect of TJ-20 and provide a scientific basis for the clinical use of TJ-20 for RA.
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Exogenous Expressions of FTO Wild-Type and R316Q Mutant Proteins Caused an Increase in HNRPK Levels in 3T3-L1 Cells as Demonstrated by DIGE Analysis
Fat mass and obesity-associated protein is an enzyme that oxidatively demethylates DNA. Although there are numerous studies regarding the catalytic function of FTO, the overall existence or absence of FTO on cellular proteome has not been investigated. This study investigated the changes in the soluble proteome of 3T3-L1 cells upon expression of the WT and the mutant (R316Q) FTO proteins. Protein extracts prepared from 3T3-L1 cells expressing either the WT or the mutant FTO proteins were used in DIGE experiments. Analysis of the data revealed the number of spots matched to every member and there were 350 ± 20 spots with 30.5% overall mean coefficient of variation. Eleven regulated protein spots were excised from the gels and identified by MALDI-TOF/TOF. One of the identified proteins was heterogeneous nuclear ribonucleoprotein K, which displayed more than 2.6- and 3.7-fold increases in its abundance in the WT and the mutant FTO expressing cells, respectively. Western blot analysis validated these observations. This is the first study revealing the presence of a parallel increase in expressions of FTO and HNRNPK proteins. This increase may codictate the metabolic changes occurring in the cell and may attribute a significance to HNRNPK in FTO-associated transformations.
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Brain Multimodality Monitoring: A New Tool in Neurocritical Care of Comatose Patients
Neurocritical care patients are at risk of developing secondary brain injury from inflammation, ischemia, and edema that follows the primary insult. Recognizing clinical deterioration due to secondary injury is frequently challenging in comatose patients. Multimodality monitoring (MMM) encompasses various tools to monitor cerebral metabolism, perfusion, and oxygenation aimed at detecting these changes to help modify therapies before irreversible injury sets in. These tools include intracranial pressure (ICP) monitors, transcranial Doppler (TCD), Hemedex™ (thermal diffusion probe used to measure regional cerebral blood flow), microdialysis catheter (used to measure cerebral metabolism), Licox™ (probe used to measure regional brain tissue oxygen tension), and continuous electroencephalography. Although further research is needed to demonstrate their impact on improving clinical outcomes, their contribution to illuminate the black box of the brain in comatose patients is indisputable. In this review, we further elaborate on commonly used MMM parameters, tools used to measure them, and the indications for monitoring per current consensus guidelines.
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Accuracy Evaluation of a Stereolithographic Surgical Template for Dental Implant Insertion Using 3D Superimposition Protocol
The aim of this study was to evaluate the accuracy of a stereolithographic template, with sleeve structure incorporated into the design, for computer-guided dental implant insertion in partially edentulous patients. Materials and Methods. Sixty-five implants were placed in twenty-five consecutive patients with a stereolithographic surgical template. After surgery, digital impression was taken and 3D inaccuracy of implants position at entry point, apex, and angle deviation was measured using an inspection tool software. Mann–Whitney test was used to compare accuracy between maxillary and mandibular surgical guides. A value
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Monitoring and Forecasting Air Pollution Levels by Exploiting Satellite, Ground-Based, and Synoptic Data, Elaborated with Regression Models
This paper presents some of the results of a project that aimed at the design and implementation of a system for the spatial mapping and forecasting the temporal evolution of air pollution from dust transport from the Sahara Desert into the eastern Mediterranean and secondarily from anthropogenic sources, focusing over Cyprus. Monitoring air pollution (aerosols) in near real-time is accomplished by using spaceborne and in situ platforms. The results of the development of a system for forecasting pollution levels in terms of particulate matter concentrations are presented. The aim of the present study is to utilize the recorded PM10 (particulate matter with aerodynamic diameter less than 10 μm) ground measurements, Aerosol Optical Depth retrievals from satellite, and the prevailing synoptic conditions established by Artificial Neural Networks, in order to develop regression models that will be able to predict the spatial and temporal variability of PM10 in Cyprus. The core of the forecasting system comprises an appropriately designed neural classification system which clusters synoptic maps, Aerosol Optical Depth data from the Aqua satellite, and ground measurements of particulate matter. By exploiting the above resources, statistical models for forecasting pollution levels were developed.
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Characterization of constitutive and acid-induced outwardly rectifying chloride currents in immortalized mouse distal tubular cells
Publication date: Available online 5 May 2017
Source:Biochimica et Biophysica Acta (BBA) - General Subjects
Author(s): William C. Valinsky, Rhian M. Touyz, Alvin Shrier
Thiazides block Na+ reabsorption while enhancing Ca2+ reabsorption in the kidney. As previously demonstrated in immortalized mouse DCT (MDCT) cells, chlorothiazide application induced a robust plasma membrane hyperpolarization, which increased Ca2+ uptake. This essential thiazide-induced hyperpolarization was prevented by the Cl− channel inhibitor 5-Nitro-2-(3-phenylpropylamino) benzoic acid (NPPB), implicating NPPB-sensitive Cl− channels, however the nature of these Cl− channels has been rarely described in the literature. Here we show that MDCT cells express a dominant, outwardly rectifying Cl− current at extracellular pH7.4. This constitutive Cl− current was more permeable to larger anions (Eisenman sequence I; I−>Br−≥Cl−) and was substantially inhibited by >100mM [Ca2+]o, which distinguished it from ClC-K2/Barttin. Moreover, the constitutive Cl− current was blocked by NPPB, along with other Cl− channel inhibitors (DIDS, FFA). Subjecting the MDCT cells to an acidic extracellular solution (pH<5.5) induced a substantially larger outwardly rectifying NPPB-sensitive Cl− current. This acid-induced Cl− current was also anion permeable (I−>Br−>Cl−), but was distinguished from the constitutive Cl− current by its rectification characteristics, ion sensitivities, and response to FFA. In addition, we have identified similar outwardly rectifying and acid-sensitive currents in immortalized cells from the inner medullary collecting duct (mIMCD-3 cells). Expression of an acid-induced Cl− current would be particularly relevant in the acidic IMCD (pH<5.5). To our knowledge, the properties of these Cl− currents are unique and provide the mechanisms to account for the Cl− efflux previously speculated to be present in MDCT cells.
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Source:Biochimica et Biophysica Acta (BBA) - General Subjects
Author(s): William C. Valinsky, Rhian M. Touyz, Alvin Shrier
Thiazides block Na+ reabsorption while enhancing Ca2+ reabsorption in the kidney. As previously demonstrated in immortalized mouse DCT (MDCT) cells, chlorothiazide application induced a robust plasma membrane hyperpolarization, which increased Ca2+ uptake. This essential thiazide-induced hyperpolarization was prevented by the Cl− channel inhibitor 5-Nitro-2-(3-phenylpropylamino) benzoic acid (NPPB), implicating NPPB-sensitive Cl− channels, however the nature of these Cl− channels has been rarely described in the literature. Here we show that MDCT cells express a dominant, outwardly rectifying Cl− current at extracellular pH7.4. This constitutive Cl− current was more permeable to larger anions (Eisenman sequence I; I−>Br−≥Cl−) and was substantially inhibited by >100mM [Ca2+]o, which distinguished it from ClC-K2/Barttin. Moreover, the constitutive Cl− current was blocked by NPPB, along with other Cl− channel inhibitors (DIDS, FFA). Subjecting the MDCT cells to an acidic extracellular solution (pH<5.5) induced a substantially larger outwardly rectifying NPPB-sensitive Cl− current. This acid-induced Cl− current was also anion permeable (I−>Br−>Cl−), but was distinguished from the constitutive Cl− current by its rectification characteristics, ion sensitivities, and response to FFA. In addition, we have identified similar outwardly rectifying and acid-sensitive currents in immortalized cells from the inner medullary collecting duct (mIMCD-3 cells). Expression of an acid-induced Cl− current would be particularly relevant in the acidic IMCD (pH<5.5). To our knowledge, the properties of these Cl− currents are unique and provide the mechanisms to account for the Cl− efflux previously speculated to be present in MDCT cells.
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Conjunctival Lymphoma in a Patient on Fingolimod for Relapsing-Remitting Multiple Sclerosis
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Evisceration With Injectable Hydrogel Implant in a Rabbit Model
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Clinical Response to Tocilizumab in Severe Thyroid Eye Disease
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Correction of Lower Eyelid Retraction Using Acellular Human Dermis During Orbital Decompression
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Dacryoendoscopic Features in a Case of Canaliculitis With Concretions
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Acute Orbital Syndrome in Herpes Zoster Ophthalmicus: Clinical Features of 7 Cases
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Transarterial Embolization of a Spontaneous Intraorbital Arteriovenous Fistula With n-BCA Glue
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The Bleph and the Brain: The Effect of Upper Eyelid Surgery on Chronic Headaches
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Tissue Engineering in Ophthalmology: Implications for Eyelid Reconstruction
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Clinical Features and Treatment Outcomes of Orbital Inflammatory Disease in Singapore: A 10-Year Clinicopathologic Review
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Aesthetic Abstracts and Citations
No abstract available
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Thyroid-Related Orbital Decompression Surgery: A Multivariate Analysis of Risk Factors and Outcomes
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Ethmoid Silent Sinus Syndrome Following Orbital Trauma
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Virtual Fitting, Selection, and Cutting of Preformed Anatomic Orbital Implants
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Familial Incomplete Punctal Canalization: Clinical and Fourier Domain Optical Coherence Tomography Features
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Periorbital Autologous Fat Grafting in Facial Nerve Palsy
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A Conjunctival Melanoma Causing Bloody Tears
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“Silent Sinus Syndrome” Following Orbital Trauma: A Case Series and Review of the Literature
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Re: “Secondary Orbital Reconstruction in Patients With Prior Orbital Fracture Repair”
No abstract available
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Orbitofacial Metastatic Basal Cell Carcinoma: Report of 10 Cases
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Gastrointestinal mantle cell lymphoma with isolated mass and multiple lymphomatous polyposis: report of two cases
Abstract
We herein report two patients with mantle cell lymphoma (MCL), who had isolated mass and multiple lymphomatous polyposis (MLP) in the gastrointestinal tract. In case 1, esophagogastroduodenoscopy revealed a protruding mass in the duodenum and double-balloon endoscopy disclosed numerous polypoid lesions in the ileum. Case 2 had polyposis in the duodenum and a large mass-forming lesion in the ascending colon. Based on the histologic and immunohistochemical findings of the biopsy specimens, the diagnosis of MCL was made in both patients. A combination of isolated mass and MLP is considered as characteristic endoscopic findings of intestinal lesions of MCL.
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Interferon-free therapy with sofosbuvir plus ribavirin for successful treatment of genotype 2 hepatitis C virus with lichen planus: a case report
Abstract
Hepatitis C virus (HCV) infection remains the main cause of liver disease and can lead to chronic hepatitis, cirrhosis, and hepatocellular carcinoma. HCV may also develop extrahepatic manifestations in the skin, eyes, joints, kidneys, nervous system, and immune system. In fact, several studies reported that up to 70% of HCV patients experienced extrahepatic manifestations. Lichen planus (LP), which is an immune system disorder that is triggered by viral infections, allergens, and stress, can affect the skin, mouth, nails, and scalp. The association of LP with HCV has been reported, but the effect of HCV treatment on LP remission is controversial. We encountered a 53-year-old man with HCV genotype 2a and LP that were successfully treated with sofosbuvir and ribavirin for 12 weeks. After treatment, he achieved sustained virological response against HCV and remission of erosive LP lesions on the lip. In the era of interferon (IFN)-based treatment for HCV, exacerbation of autoimmune diseases is a common adverse event. Therefore, use of an IFN-free regimen of direct-acting antivirals for HCV might prevent the extrahepatic manifestation of an immune disorder.
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CT colonography: role in FOBT-based screening programs for colorectal cancer
Abstract
Computed tomographic colonography (CTC) is a minimally invasive imaging examination for the colon, and is safe, well tolerated and accurate for the detection of colorectal cancer (CRC) and advanced adenoma. While the role of CTC as a primary test for population screening of CRC is under investigation, the fecal occult blood test (FOBT) has been recommended for population screening of CRC in Europe. Subjects with positive FOBT are invited to undergo total colonoscopy, which has some critical issues, such as suboptimal compliance, contraindications and the possibility of an incomplete exploration of the colon. Based on available data, the integration of CTC in FOBT-based population screening programs for CRC may fall into three scenarios. First, CTC is recommended in FOBT-positive subjects when colonoscopy is refused, incomplete or contraindicated. For these indications CTC should replace double-contrast barium enema. Second, conversely, CTC is not currently recommended as a second-level examination prior to colonoscopy in all FOBT-positive subjects, as this strategy is most probably not cost-effective. Finally, CTC may be considered instead of colonoscopy for surveillance after adenoma removal, but specific studies are needed.
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Uptake of 123 I-metaiodobenzylguanidine by gastrointestinal stromal tumor
Abstract
A 52-year-old woman was admitted with a large intraabdominal mass. 123I- metaiodobenzylguanidine (123I-MIBG) scintigraphy revealed considerable 123I-MIBG accumulation by the mass that was compatible with a diagnosis of paraganglioma. However, a spindle cell tumor that was identified using endoscopic ultrasound-guided fine needle aspiration before surgery was positive for CD117. The surgically resected mass was confirmed as a gastrointestinal stromal tumor (GIST). Although the mechanism of 123I-MIBG uptake by GIST has not been elucidated, GIST should be included in the differential diagnosis of intra-abdominal tumor with 123I-MIBG uptake.
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Utility of Doppler ultrasonography for diagnosing and assessing treatment effects in liver compartment syndrome
Abstract
Liver compartment syndrome is a life-threatening complication of hepatic subcapsular hematoma; diagnosis and assessment of treatment effects are therefore important. We report a rare case of liver compartment syndrome due to spontaneous hepatic subcapsular hematoma without any underlying conditions, in which Doppler ultrasonography (US) proved useful in both diagnosis and assessment of treatment effects. A 32-year-old woman experienced sudden epigastralgia and was diagnosed with hepatic subcapsular hematoma in the right lobe, based on contrast-enhanced computed tomography. Hepatic arteriography showed active hemorrhage and Doppler US showed retrograde flow in the right portal vein. From these findings, we diagnosed hepatic subcapsular hematoma complicated with liver compartment syndrome, and performed embolization of the bleeding point and percutaneous hematoma drainage. After these medical procedures, normalized antegrade flow in the right portal vein was observed on Doppler US. No underlying conditions contributing to hematoma were identified. In this case, Doppler US was useful for both diagnosis and assessment of treatment effects in liver compartment syndrome. When we examine patients with hepatic subcapsular hematoma, Doppler US should be used to diagnose the presence of liver compartment syndrome and assess treatment effects.
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Farnesoid X receptor induces Takeda G-protein receptor 5 Crosstalk to regulate Bile Acid Synthesis and Hepatic Metabolism [Metabolism]
The bile acid-activated receptors, nuclear farnesoid X receptor (FXR) and the membrane Takeda G-protein receptor 5 (TGR5), are known to improve glucose and insulin sensitivity in obese and diabetic mice. However, the metabolic roles of these two receptors and the underlying mechanisms are incompletely understood. Here we studied the effects of the dual FXR and TGR5 agonist INT-767 on hepatic bile acid synthesis and intestinal secretion of glucagon-like peptide-1 (GLP-1) in wild type, Fxr-/-, and Tgr5-/- mice. INT-767 efficaciously stimulated intracellular Ca2+ levels, cAMP activity, and GLP-1 secretion and improved glucose and lipid metabolism more than did the FXR-selective obeticholic acid and TGR5-selective INT-777 agonists. Interestingly, INT-767 reduced expression of the genes in the classic bile acid synthesis pathway but induced those in the alternative pathway, which is consistent with decreased tauro-cholic acid and increased tauro-muricholic acids in bile. Furthermore, FXR activation induced expression of FXR target genes including fibroblast growth factor 15, and unexpectedly Tgr5 and prohormone convertase 1/3 gene expression in the ileum. We identified an FXR responsive element on the Tgr5 gene promoter. Fxr-/- and Tgr5-/- mice exhibited reduced GLP-1 secretion, which was stimulated by INT-767 in the Tgr5-/- mice but not in the Fxr-/- mice. Our findings uncovered a novel mechanism in which INT-767 activation of FXR induces Tgr5 gene expression and increases Ca2+ levels and cAMP activity to stimulate GLP-1 secretion and improve hepatic glucose and lipid metabolism in high fat diet-induced obese mice. Activation of both FXR and TGR5 therefore, may represent an effective therapy for managing hepatic steatosis, obesity and diabetes.
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The beneficial hemodynamic effects of afterload reduction by sodium nitroprusside during rewarming from experimental hypothermia
Publication date: Available online 4 May 2017
Source:Cryobiology
Author(s): Brage Håheim, Timofey Kondratiev, Erik Sveberg Dietrichs, Torkjel Tveita
BackgroundRewarming from hypothermia is associated with depressed cardiac function, known as hypothermia-induced cardiac dysfunction (HCD), and increased systemic vascular resistance (SVR). Previous studies on pharmacological treatment of HCD have demonstrated beneficial effects when using drugs with the combined effects; cardiac inotropic support and peripheral vasodilation. The presented study aims to investigate the isolated effects of arterial dilatation on cardiac functional variables during rewarming from hypothermia using sodium nitroprusside (SNP).MethodsWe utilized a rat model designed to induce HCD following 4 h at 15 °C and rewarming. To study effects on left ventricular (LV) functional variables in response to afterload reduction by SNP during rewarming a conductance catheter was used. Index of LV contractility, preload recruitable stroke work (PRSW), was obtained with inferior vena cava occlusions at 37 °C before and after hypothermia. Pressure signals from a catheter in the left femoral artery was used to pharmacologically adjust SVR.ResultsAfter rewarming both animal groups showed significant reduction in both SV and CO as a manifestation of HCD. However, compared to saline controls, SV and CO in SNP-treated animals increased significantly during rewarming in response to afterload reduction displayed as reduced SVR, mean arterial- and end-systolic pressures. The cardiac contractility variable PRSW was equally reduced after rewarming in both groups.ConclusionWhen rewarming the present model of HCD a significant increase in SVR takes place. In this context, pharmacologic intervention aimed at reducing SVR show clear positive results on CO and SV. However, a reduction in SVR alone is not sufficient to fully alleviate CO during HCD, and indicate the need of additional inotropic support.
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Source:Cryobiology
Author(s): Brage Håheim, Timofey Kondratiev, Erik Sveberg Dietrichs, Torkjel Tveita
BackgroundRewarming from hypothermia is associated with depressed cardiac function, known as hypothermia-induced cardiac dysfunction (HCD), and increased systemic vascular resistance (SVR). Previous studies on pharmacological treatment of HCD have demonstrated beneficial effects when using drugs with the combined effects; cardiac inotropic support and peripheral vasodilation. The presented study aims to investigate the isolated effects of arterial dilatation on cardiac functional variables during rewarming from hypothermia using sodium nitroprusside (SNP).MethodsWe utilized a rat model designed to induce HCD following 4 h at 15 °C and rewarming. To study effects on left ventricular (LV) functional variables in response to afterload reduction by SNP during rewarming a conductance catheter was used. Index of LV contractility, preload recruitable stroke work (PRSW), was obtained with inferior vena cava occlusions at 37 °C before and after hypothermia. Pressure signals from a catheter in the left femoral artery was used to pharmacologically adjust SVR.ResultsAfter rewarming both animal groups showed significant reduction in both SV and CO as a manifestation of HCD. However, compared to saline controls, SV and CO in SNP-treated animals increased significantly during rewarming in response to afterload reduction displayed as reduced SVR, mean arterial- and end-systolic pressures. The cardiac contractility variable PRSW was equally reduced after rewarming in both groups.ConclusionWhen rewarming the present model of HCD a significant increase in SVR takes place. In this context, pharmacologic intervention aimed at reducing SVR show clear positive results on CO and SV. However, a reduction in SVR alone is not sufficient to fully alleviate CO during HCD, and indicate the need of additional inotropic support.
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Cryopreservation of boar sperm induces differential microRNAs expression
Publication date: Available online 3 May 2017
Source:Cryobiology
Author(s): Yan Zhang, Dinghui Dai, Yu Chang, Yuan Li, Ming Zhang, Guangbin Zhou, Zhanghua Peng, Changjun Zeng
Lower conception rates and litter sizes limit the wide use of artificial insemination with frozen-thawed boar sperm, due to a lack of understanding of the mechanisms that cause cryodamage and cryoinjury to sperm during cryopreservation. CryoMiRs, a family of freeze-related microRNAs (miRNAs), are associated with freeze tolerance, and regulate metabolism in mammalian hibernators and insects. Thus, we speculate that miRNAs maybe involved in the regulation of the freeze-thaw process and may affect boar sperm function. In this study, we studied the differential expression of 46 miRNAs that have roles in spermatogenesis, sperm maturation, and sperm quality in response to cryopreservation (with or without 3% glycerol). The results indicated that, in response to cryopreservation with 3% glycerol, 14 miRNAs were significantly up-regulated, but only two miRNAs (miR-22 and miR-450b-5p) were significantly down-regulated, relative to fresh sperm. Preservation with 3% glycerol caused up-regulation of 17 miRNAs, but only caused down-regulation of one miRNA (miR-24), relative to sperm cryopreserved without glycerol. Functional annotations of these differentially expressed miRNAs indicated that these miRNAs and their targets are mainly associated with metabolic and cellular processes. Therefore, our findings show that cryopreservation results in changes in miRNA expression, and suggest that the anti-freeze mechanisms of boar sperm need to be studied further.
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Source:Cryobiology
Author(s): Yan Zhang, Dinghui Dai, Yu Chang, Yuan Li, Ming Zhang, Guangbin Zhou, Zhanghua Peng, Changjun Zeng
Lower conception rates and litter sizes limit the wide use of artificial insemination with frozen-thawed boar sperm, due to a lack of understanding of the mechanisms that cause cryodamage and cryoinjury to sperm during cryopreservation. CryoMiRs, a family of freeze-related microRNAs (miRNAs), are associated with freeze tolerance, and regulate metabolism in mammalian hibernators and insects. Thus, we speculate that miRNAs maybe involved in the regulation of the freeze-thaw process and may affect boar sperm function. In this study, we studied the differential expression of 46 miRNAs that have roles in spermatogenesis, sperm maturation, and sperm quality in response to cryopreservation (with or without 3% glycerol). The results indicated that, in response to cryopreservation with 3% glycerol, 14 miRNAs were significantly up-regulated, but only two miRNAs (miR-22 and miR-450b-5p) were significantly down-regulated, relative to fresh sperm. Preservation with 3% glycerol caused up-regulation of 17 miRNAs, but only caused down-regulation of one miRNA (miR-24), relative to sperm cryopreserved without glycerol. Functional annotations of these differentially expressed miRNAs indicated that these miRNAs and their targets are mainly associated with metabolic and cellular processes. Therefore, our findings show that cryopreservation results in changes in miRNA expression, and suggest that the anti-freeze mechanisms of boar sperm need to be studied further.
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Expansion and cryopreservation of porcine and human corneal endothelial cells
Publication date: Available online 2 May 2017
Source:Cryobiology
Author(s): Leah A. Marquez-Curtis, Locksley E. McGann, Janet A.W. Elliott
Impairment of the corneal endothelium causes blindness that afflicts millions worldwide and constitutes the most often cited indication for corneal transplants. The scarcity of donor corneas has prompted the alternative use of tissue-engineered grafts which requires the ex vivo expansion and cryopreservation of corneal endothelial cells. The aims of this study are to culture and identify the conditions that will yield viable and functional corneal endothelial cells after cryopreservation. Previously, using human umbilical vein endothelial cells (HUVECs), we employed a systematic approach to optimize the post-thaw recovery of cells with high membrane integrity and functionality. Here, we investigated whether improved protocols for HUVECs translate to the cryopreservation of corneal endothelial cells, despite the differences in function and embryonic origin of these cell types. First, we isolated endothelial cells from pig corneas and then applied an interrupted slow cooling protocol in the presence of dimethyl sulfoxide (Me2SO), with or without hydroxyethyl starch (HES). Next, we isolated and expanded endothelial cells from human corneas and applied the best protocol verified using porcine cells. We found that slow cooling at 1 °C/min in the presence of 5% Me2SO and 6% HES, followed by rapid thawing after liquid nitrogen storage, yields membrane-intact cells that could form monolayers expressing the tight junction marker ZO-1 and cytoskeleton F-actin, and could form tubes in reconstituted basement membrane matrix. Thus, we show that a cryopreservation protocol optimized for HUVECs can be applied successfully to corneal endothelial cells, and this could provide a means to address the need for off-the-shelf cryopreserved cells for corneal tissue engineering and regenerative medicine.
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Source:Cryobiology
Author(s): Leah A. Marquez-Curtis, Locksley E. McGann, Janet A.W. Elliott
Impairment of the corneal endothelium causes blindness that afflicts millions worldwide and constitutes the most often cited indication for corneal transplants. The scarcity of donor corneas has prompted the alternative use of tissue-engineered grafts which requires the ex vivo expansion and cryopreservation of corneal endothelial cells. The aims of this study are to culture and identify the conditions that will yield viable and functional corneal endothelial cells after cryopreservation. Previously, using human umbilical vein endothelial cells (HUVECs), we employed a systematic approach to optimize the post-thaw recovery of cells with high membrane integrity and functionality. Here, we investigated whether improved protocols for HUVECs translate to the cryopreservation of corneal endothelial cells, despite the differences in function and embryonic origin of these cell types. First, we isolated endothelial cells from pig corneas and then applied an interrupted slow cooling protocol in the presence of dimethyl sulfoxide (Me2SO), with or without hydroxyethyl starch (HES). Next, we isolated and expanded endothelial cells from human corneas and applied the best protocol verified using porcine cells. We found that slow cooling at 1 °C/min in the presence of 5% Me2SO and 6% HES, followed by rapid thawing after liquid nitrogen storage, yields membrane-intact cells that could form monolayers expressing the tight junction marker ZO-1 and cytoskeleton F-actin, and could form tubes in reconstituted basement membrane matrix. Thus, we show that a cryopreservation protocol optimized for HUVECs can be applied successfully to corneal endothelial cells, and this could provide a means to address the need for off-the-shelf cryopreserved cells for corneal tissue engineering and regenerative medicine.
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3-D printing provides a novel approach for standardization and reproducibility of freezing devices
Publication date: Available online 29 April 2017
Source:Cryobiology
Author(s): E Hu, William Childress, Terrence R. Tiersch
Cryopreservation has become an important and accepted tool for long-term germplasm conservation of animals and plants. To protect genetic resources, repositories have been developed with national and international cooperation. For a repository to be effective, the genetic material submitted must be of good quality and comparable to other submissions. However, due to a variety of reasons, including constraints in knowledge and available resources, cryopreservation methods for aquatic species vary widely across user groups which reduces reproducibility and weakens quality control. Herein we describe a standardizable freezing device produced using 3-dimensional (3-D) printing and introduce the concept of network sharing to achieve aggregate high-throughput cryopreservation for aquatic species. The objectives were to: 1) adapt widely available polystyrene foam products that would be inexpensive, portable, and provide adequate work space; 2) develop a design suitable for 3-D printing that could provide multiple configurations, be inexpensive, and easy to use, and 3) evaluate various configurations to attain freezing rates suitable for various common cryopreservation containers. Through this approach, identical components can be accessed globally, and we demonstrated that 3-D printers can be used to fabricate parts for standardizable freezing devices yielding relevant and reproducible cooling rates across users. With standardized devices for freezing, methods and samples can harmonize into an aggregated high-throughput pathway not currently available for aquatic species repository development.
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Source:Cryobiology
Author(s): E Hu, William Childress, Terrence R. Tiersch
Cryopreservation has become an important and accepted tool for long-term germplasm conservation of animals and plants. To protect genetic resources, repositories have been developed with national and international cooperation. For a repository to be effective, the genetic material submitted must be of good quality and comparable to other submissions. However, due to a variety of reasons, including constraints in knowledge and available resources, cryopreservation methods for aquatic species vary widely across user groups which reduces reproducibility and weakens quality control. Herein we describe a standardizable freezing device produced using 3-dimensional (3-D) printing and introduce the concept of network sharing to achieve aggregate high-throughput cryopreservation for aquatic species. The objectives were to: 1) adapt widely available polystyrene foam products that would be inexpensive, portable, and provide adequate work space; 2) develop a design suitable for 3-D printing that could provide multiple configurations, be inexpensive, and easy to use, and 3) evaluate various configurations to attain freezing rates suitable for various common cryopreservation containers. Through this approach, identical components can be accessed globally, and we demonstrated that 3-D printers can be used to fabricate parts for standardizable freezing devices yielding relevant and reproducible cooling rates across users. With standardized devices for freezing, methods and samples can harmonize into an aggregated high-throughput pathway not currently available for aquatic species repository development.
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Cold mortality is not caused by oxygen limitation or loss of ion homeostasis in the tropical freshwater shrimp Macrobrachium rosenbergii
Publication date: Available online 28 April 2017
Source:Cryobiology
Author(s): Lisa B. Jørgensen, Heath A. MacMillan, Johannes Overgaard
Using the tropical crustacean Macrobrachium rosenbergii we investigate two popular hypotheses proposed to explain loss of function in ectotherms exposed to critically high and low temperatures. Specifically, we examine whether acute cold stress disrupts hemolymph and muscle ion balance or causes a loss of oxygen availability. We found that acute cold stress causes loss of righting response at 13 °C, but that a cold-induced loss of ion-balance only occurs after onset of mortality. In regards to oxygen availability, we found no decrease in hemolymph oxygen content during cold exposure, and no changes in the concentrations of the anaerobic end products l-lactate and succinate in the tail muscle of the shrimp. Therefore, our results support neither of these two popular hypotheses and it remains unknown what physiological perturbations determine the lower limits of thermal tolerance in Macrobrachium rosenbergii.
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Source:Cryobiology
Author(s): Lisa B. Jørgensen, Heath A. MacMillan, Johannes Overgaard
Using the tropical crustacean Macrobrachium rosenbergii we investigate two popular hypotheses proposed to explain loss of function in ectotherms exposed to critically high and low temperatures. Specifically, we examine whether acute cold stress disrupts hemolymph and muscle ion balance or causes a loss of oxygen availability. We found that acute cold stress causes loss of righting response at 13 °C, but that a cold-induced loss of ion-balance only occurs after onset of mortality. In regards to oxygen availability, we found no decrease in hemolymph oxygen content during cold exposure, and no changes in the concentrations of the anaerobic end products l-lactate and succinate in the tail muscle of the shrimp. Therefore, our results support neither of these two popular hypotheses and it remains unknown what physiological perturbations determine the lower limits of thermal tolerance in Macrobrachium rosenbergii.
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Long-term cryopreservation of reaggregated pancreatic islets resulting in successful transplantation in rats
Publication date: Available online 5 May 2017
Source:Cryobiology
Author(s): Sonia Rawal, Stephen Harrington, S. Janette Williams, Karthik Ramachandran, Lisa Stehno-Bittel
Preservation of pancreatic islets for long-term storage of islet used for transplantation or research has long been a goal. Unfortunately, few studies on long-term islet cryopreservation (1 month and longer) have reported positive outcomes in terms of islet yield, survival and function. In general, single cells have been shown to tolerate the cryopreservation procedure better than tissues/multicellular structures like islets. Thus, we optimized a method to cryopreserve single islet cells and, after thawing, reaggregated them into islet spheroids. Cryopreserved (CP) single human islet cells formed spheroids efficiently within 3–5 days after thawing. Approximately 79% of islet cells were recovered following the single-cell cryopreservation protocol. Viability after long-term cryopreservation (4 weeks or more) was significantly higher in the CP islet cell spheroids (97.4 ± 0.4%) compared to CP native islets (14.6 ± 0.4%). Moreover, CP islet cell spheroids had excellent viability even after months in culture (88.5 ± 1.6%). Metabolic activity was 4–5 times higher in CP islet cell spheroids than CP native islets at 24 and 48 h after thawing. Diabetic rats transplanted with CP islet cell spheroids were normoglycemic for 10 months, identical to diabetic rats transplanted with fresh islets. However, the animals receiving fresh islets required a higher volume of transplanted tissue to achieve normoglycemia compared to those transplanted with CP islet cell spheroids. By cryopreserving single cells instead of intact islets, we achieved highly viable and functional islets after thawing that required lower tissue volumes to reverse diabetes in rats.
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Source:Cryobiology
Author(s): Sonia Rawal, Stephen Harrington, S. Janette Williams, Karthik Ramachandran, Lisa Stehno-Bittel
Preservation of pancreatic islets for long-term storage of islet used for transplantation or research has long been a goal. Unfortunately, few studies on long-term islet cryopreservation (1 month and longer) have reported positive outcomes in terms of islet yield, survival and function. In general, single cells have been shown to tolerate the cryopreservation procedure better than tissues/multicellular structures like islets. Thus, we optimized a method to cryopreserve single islet cells and, after thawing, reaggregated them into islet spheroids. Cryopreserved (CP) single human islet cells formed spheroids efficiently within 3–5 days after thawing. Approximately 79% of islet cells were recovered following the single-cell cryopreservation protocol. Viability after long-term cryopreservation (4 weeks or more) was significantly higher in the CP islet cell spheroids (97.4 ± 0.4%) compared to CP native islets (14.6 ± 0.4%). Moreover, CP islet cell spheroids had excellent viability even after months in culture (88.5 ± 1.6%). Metabolic activity was 4–5 times higher in CP islet cell spheroids than CP native islets at 24 and 48 h after thawing. Diabetic rats transplanted with CP islet cell spheroids were normoglycemic for 10 months, identical to diabetic rats transplanted with fresh islets. However, the animals receiving fresh islets required a higher volume of transplanted tissue to achieve normoglycemia compared to those transplanted with CP islet cell spheroids. By cryopreserving single cells instead of intact islets, we achieved highly viable and functional islets after thawing that required lower tissue volumes to reverse diabetes in rats.
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Red blood cell membrane water permeability increases with length of ex vivo storage
Publication date: Available online 26 April 2017
Source:Cryobiology
Author(s): Abdulrahman Alshalani, Jason P. Acker
Water transport across the red blood cell (RBC) membrane is an essential cell function that needs to be preserved during ex vivo storage. Progressive biochemical depletion during storage can result in significant conformational and compositional changes to the membrane. Characterizing the changes to RBC water permeability can help in evaluating the quality of stored blood products and aid in the development of improved methods for the cryopreservation of red blood cells. This study aimed to characterize the water permeability (Lp), osmotically inactive fraction (b), and Arrhenius activation energy (Ea) at defined storage time-points throughout storage and to correlate the observed results with other in vitro RBC quality parameters. RBCs were collected from age- and sex-matched blood donors. A stopped flow spectrophotometer was used to determine Lp and b by monitoring changes in hemoglobin autofluorescence when RBCs were exposed to anisotonic solutions. Experimental values of Lp were characterized at three different temperatures (4, 20 and 37 °C) to determine the Ea. Results showed that Lp, b, and Ea of stored RBCs significantly increase by day 21 of storage. Degradation of the RBC membrane with length of storage was seen as an increase in hemolysis and supernatant potassium, and a decrease in deformability, mean corpuscular hemoglobin concentration and supernatant sodium. RBC osmotic characteristics were shown to change with storage and correlate with changes in RBC membrane quality metrics. Monitoring water parameters is a predictor of membrane damage and loss of membrane integrity in ex vivo stored RBCs.
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Source:Cryobiology
Author(s): Abdulrahman Alshalani, Jason P. Acker
Water transport across the red blood cell (RBC) membrane is an essential cell function that needs to be preserved during ex vivo storage. Progressive biochemical depletion during storage can result in significant conformational and compositional changes to the membrane. Characterizing the changes to RBC water permeability can help in evaluating the quality of stored blood products and aid in the development of improved methods for the cryopreservation of red blood cells. This study aimed to characterize the water permeability (Lp), osmotically inactive fraction (b), and Arrhenius activation energy (Ea) at defined storage time-points throughout storage and to correlate the observed results with other in vitro RBC quality parameters. RBCs were collected from age- and sex-matched blood donors. A stopped flow spectrophotometer was used to determine Lp and b by monitoring changes in hemoglobin autofluorescence when RBCs were exposed to anisotonic solutions. Experimental values of Lp were characterized at three different temperatures (4, 20 and 37 °C) to determine the Ea. Results showed that Lp, b, and Ea of stored RBCs significantly increase by day 21 of storage. Degradation of the RBC membrane with length of storage was seen as an increase in hemolysis and supernatant potassium, and a decrease in deformability, mean corpuscular hemoglobin concentration and supernatant sodium. RBC osmotic characteristics were shown to change with storage and correlate with changes in RBC membrane quality metrics. Monitoring water parameters is a predictor of membrane damage and loss of membrane integrity in ex vivo stored RBCs.
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Pentoxifylline increase sperm motility in devitrified spermatozoa from asthenozoospermic patient without damage chromatin and DNA integrity
Publication date: Available online 25 April 2017
Source:Cryobiology
Author(s): Ali Nabi, Mohammad Ali Khalili, Farzaneh Fesahat, Alireza Talebi, Saeed Ghasemi-Esmailabad
The freeze–thaw process results in reduced motility, viability and fertilization potential of human spermatozoa. So, a variety of substances were evaluated in order to enhance human sperm resistance to the stress of cryopreservation, such as Pentoxifylline (PTX) for improving the Intracytoplasmic sperm injection (ICSI) outcomes. The aim was to investigate the effect of PTX on sperm parameters and chromatin/DNA integrity of asthenozoospermic semen post vitrification. A total of 30 semen specimens were obtained from infertile men with asthenozoospermia. The cryoprotectant-free vitrification was performed for the samples after assessment of sperm parameters. After warming, each sample was exposed for 30 min to 3.6 mmol/l PTX in experimental group and the control group without any treatment apposing at 37 °C for 30 min in regard, to repeat all in vitro analysis (sperm parameters and DNA integrity assay). Regardless of the vitrification devastating impacts on sperm parameters, incubation of post vitrified samples with PTX increased the rate of progressive motility (P < 0.01). Moreover, PTX addition did not significantly damage DNA integrity of asthenozoospermic sperm samples. The data showed that PTX was able to improve sperm movement without any adverse effects on sperm chromatin/DNA integrity in vitrification program.
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Source:Cryobiology
Author(s): Ali Nabi, Mohammad Ali Khalili, Farzaneh Fesahat, Alireza Talebi, Saeed Ghasemi-Esmailabad
The freeze–thaw process results in reduced motility, viability and fertilization potential of human spermatozoa. So, a variety of substances were evaluated in order to enhance human sperm resistance to the stress of cryopreservation, such as Pentoxifylline (PTX) for improving the Intracytoplasmic sperm injection (ICSI) outcomes. The aim was to investigate the effect of PTX on sperm parameters and chromatin/DNA integrity of asthenozoospermic semen post vitrification. A total of 30 semen specimens were obtained from infertile men with asthenozoospermia. The cryoprotectant-free vitrification was performed for the samples after assessment of sperm parameters. After warming, each sample was exposed for 30 min to 3.6 mmol/l PTX in experimental group and the control group without any treatment apposing at 37 °C for 30 min in regard, to repeat all in vitro analysis (sperm parameters and DNA integrity assay). Regardless of the vitrification devastating impacts on sperm parameters, incubation of post vitrified samples with PTX increased the rate of progressive motility (P < 0.01). Moreover, PTX addition did not significantly damage DNA integrity of asthenozoospermic sperm samples. The data showed that PTX was able to improve sperm movement without any adverse effects on sperm chromatin/DNA integrity in vitrification program.
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Liquidus Tracking: Large scale preservation of encapsulated 3-D cell cultures using a vitrification machine
Publication date: Available online 22 April 2017
Source:Cryobiology
Author(s): Eva Puschmann, Clare Selden, Steve Butler, Barry Fuller
Currently, cryo-banking of multicellular structures such as organoids, especially in large volumes at clinical scale >1 L, remains elusive for reasons such as insufficient dehydration and cryoprotectant additive (CPA1) penetration, slow cooling and warming rates and devitrification processes. Here we introduce the concept of Liquidus Tracking (LT) using a semi-automated process for liquid volumes of up to 450 ml including 130 ml of alginate encapsulated liver cells (AELC) that archived controlled and reversible vitrification with minimized toxicity.First a CPA solution with optimal properties for LT was developed by employing different small scale test systems. Combining sugars such as glucose and raffinose with Me2SO improved post-exposure (at +0.5 °C) viabilities from 6% ±3.6 for Me2SO alone up to 58% ±6.1 and 65% ±14.2 respectively (p < 0.01). Other permeating CPAs (e.g. ethylene glycol, propylene glycol, methanol) were investigated as partial replacements for Me2SO. A mixture of Me2SO, ethylene glycol and glucose (ratio 4:2:1– termed LTdeg) supported glass-forming tendencies with appropriate low viscosities and toxicities required for LT. When running the full LT process, using Me2SO alone, no viable cells were recovered; using LTdeg, viable recoveries were improved to 40% ±8 (p<0.001%). Further refinements of improved mixing technique further improved recovery after LT. Recoveries of specific liver cell functions such as synthesis of albumin and alpha-fetoprotein (AFP) were retained in post thaw cultures.In summary: By developing a low-toxicity CPA solution of low viscosity (LTdeg) suitable for LT and by improving the stirring system, post-warming viability of AELC of up to 90% and a AFP secretion of 89% were reached. Results show that it may be possible to develop LT as a suitable cryogenic preservation process for different cell therapy products at large scale.
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Source:Cryobiology
Author(s): Eva Puschmann, Clare Selden, Steve Butler, Barry Fuller
Currently, cryo-banking of multicellular structures such as organoids, especially in large volumes at clinical scale >1 L, remains elusive for reasons such as insufficient dehydration and cryoprotectant additive (CPA1) penetration, slow cooling and warming rates and devitrification processes. Here we introduce the concept of Liquidus Tracking (LT) using a semi-automated process for liquid volumes of up to 450 ml including 130 ml of alginate encapsulated liver cells (AELC) that archived controlled and reversible vitrification with minimized toxicity.First a CPA solution with optimal properties for LT was developed by employing different small scale test systems. Combining sugars such as glucose and raffinose with Me2SO improved post-exposure (at +0.5 °C) viabilities from 6% ±3.6 for Me2SO alone up to 58% ±6.1 and 65% ±14.2 respectively (p < 0.01). Other permeating CPAs (e.g. ethylene glycol, propylene glycol, methanol) were investigated as partial replacements for Me2SO. A mixture of Me2SO, ethylene glycol and glucose (ratio 4:2:1– termed LTdeg) supported glass-forming tendencies with appropriate low viscosities and toxicities required for LT. When running the full LT process, using Me2SO alone, no viable cells were recovered; using LTdeg, viable recoveries were improved to 40% ±8 (p<0.001%). Further refinements of improved mixing technique further improved recovery after LT. Recoveries of specific liver cell functions such as synthesis of albumin and alpha-fetoprotein (AFP) were retained in post thaw cultures.In summary: By developing a low-toxicity CPA solution of low viscosity (LTdeg) suitable for LT and by improving the stirring system, post-warming viability of AELC of up to 90% and a AFP secretion of 89% were reached. Results show that it may be possible to develop LT as a suitable cryogenic preservation process for different cell therapy products at large scale.
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Cryopreservation of oil palm (Elaeis guineensis Jacq.)
Publication date: Available online 21 April 2017
Source:Cryobiology
Author(s): Jaime A. Teixeira da Silva, Florent Engelmann
Oil palm (Elaeis guineensis Jacq.), a tropical plant, is the leading source of edible oil. This review deals with the cryopreservation of oil palm as a way to preserve this important tropical germplasm. Somatic embryos have been the most popular source of material for cryopreservation as they are propagules that are effectively produced during micropropagation. In contrast, fewer studies exist on the cryopreservation of pollen, zygotic embryos, seeds, kernels and embryogenic cell suspensions. This review highlights the ideal protocols, in detail, in a bid to offer guidance for further advances in oil palm cryopreservation.
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Source:Cryobiology
Author(s): Jaime A. Teixeira da Silva, Florent Engelmann
Oil palm (Elaeis guineensis Jacq.), a tropical plant, is the leading source of edible oil. This review deals with the cryopreservation of oil palm as a way to preserve this important tropical germplasm. Somatic embryos have been the most popular source of material for cryopreservation as they are propagules that are effectively produced during micropropagation. In contrast, fewer studies exist on the cryopreservation of pollen, zygotic embryos, seeds, kernels and embryogenic cell suspensions. This review highlights the ideal protocols, in detail, in a bid to offer guidance for further advances in oil palm cryopreservation.
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First successful vitrification of salmonid ovarian tissue
Publication date: Available online 21 April 2017
Source:Cryobiology
Author(s): Jelena Lujić, Zoran Marinović, Simona Sušnik Bajec, Ida Djurdjevič, Eszter Kása, Béla Urbányi, Ákos Horváth
Due to a lack of cryopreservation protocols for fish eggs and embryos, alternative techniques which will enable storage of female genetic resources are crucial for future development of reproduction management in conservation biology and aquaculture. Experiments were conducted to develop an optimal vitrification protocol for cryopreservation of brown trout Salmo trutta juvenile ovarian tissue. Needle immersed vitrification (NIV) method was used where ovaries were pinned on an acupuncture needle, passaged through equilibration and vitrification solutions containing different combinations and concentrations of methanol (MeOH), propylene glycol (PG) and dimethyl sulfoxide (Me2SO) and subsequently plunged into liquid nitrogen. Vitrification solutions containing equal cryoprotectant concentrations (3M Me2SO and 3M PG) yielded the highest oogonia survival rates (up to 40%) and qualitatively and quantitatively unaltered perinucleolar follicles. The method developed for brown trout could be applied to the conservation of female genetic resources of other salmonid species, including endangered and endemic species or populations.
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Source:Cryobiology
Author(s): Jelena Lujić, Zoran Marinović, Simona Sušnik Bajec, Ida Djurdjevič, Eszter Kása, Béla Urbányi, Ákos Horváth
Due to a lack of cryopreservation protocols for fish eggs and embryos, alternative techniques which will enable storage of female genetic resources are crucial for future development of reproduction management in conservation biology and aquaculture. Experiments were conducted to develop an optimal vitrification protocol for cryopreservation of brown trout Salmo trutta juvenile ovarian tissue. Needle immersed vitrification (NIV) method was used where ovaries were pinned on an acupuncture needle, passaged through equilibration and vitrification solutions containing different combinations and concentrations of methanol (MeOH), propylene glycol (PG) and dimethyl sulfoxide (Me2SO) and subsequently plunged into liquid nitrogen. Vitrification solutions containing equal cryoprotectant concentrations (3M Me2SO and 3M PG) yielded the highest oogonia survival rates (up to 40%) and qualitatively and quantitatively unaltered perinucleolar follicles. The method developed for brown trout could be applied to the conservation of female genetic resources of other salmonid species, including endangered and endemic species or populations.
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Cryoprotectants: A review of the actions and applications of cryoprotective solutes that modulate cell recovery from ultra-low temperatures
Publication date: Available online 18 April 2017
Source:Cryobiology
Author(s): Gloria D. Elliott, Shangping Wang, Barry J. Fuller
Cryopreservation has become a central technology in many areas of clinical medicine, biotechnology, and species conservation within both plant and animal biology. Cryoprotective agents (CPAs) invariably play key roles in allowing cells to be processed for storage at deep cryogenic temperatures and to be recovered with high levels of appropriate functionality. As such, these CPA solutes possess a wide range of metabolic and biophysical effects that are both necessary for their modes of action, and potentially complicating for cell biological function. Early successes with cryopreservation were achieved by empirical methodology for choosing and applying CPAs. In recent decades, it has been possible to assemble objective information about CPA modes of action and to optimize their application to living systems, but there still remain significant gaps in our understanding. This review sets out the current status on the biological and chemical knowledge surrounding CPAs, and the conflicting effects of protection versus toxicity resulting from the use of these solutes, which are often required in molar concentrations, far exceeding levels found in normal metabolism. The biophysical properties of CPAs that allow them to facilitate different approaches to cryogenic storage, including vitrification, are highlighted. The topics are discussed with reference to the historical background of applying CPAs, and the relevance of cryoprotective solutes in natural freeze tolerant organisms. Improved cryopreservation success will be an essential step in many future areas such as regenerative medicine, seed banking, or stem cell technology. To achieve this, we will need to further improve our understanding of cryobiology, where better and safer CPAs will be key requirements.
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Source:Cryobiology
Author(s): Gloria D. Elliott, Shangping Wang, Barry J. Fuller
Cryopreservation has become a central technology in many areas of clinical medicine, biotechnology, and species conservation within both plant and animal biology. Cryoprotective agents (CPAs) invariably play key roles in allowing cells to be processed for storage at deep cryogenic temperatures and to be recovered with high levels of appropriate functionality. As such, these CPA solutes possess a wide range of metabolic and biophysical effects that are both necessary for their modes of action, and potentially complicating for cell biological function. Early successes with cryopreservation were achieved by empirical methodology for choosing and applying CPAs. In recent decades, it has been possible to assemble objective information about CPA modes of action and to optimize their application to living systems, but there still remain significant gaps in our understanding. This review sets out the current status on the biological and chemical knowledge surrounding CPAs, and the conflicting effects of protection versus toxicity resulting from the use of these solutes, which are often required in molar concentrations, far exceeding levels found in normal metabolism. The biophysical properties of CPAs that allow them to facilitate different approaches to cryogenic storage, including vitrification, are highlighted. The topics are discussed with reference to the historical background of applying CPAs, and the relevance of cryoprotective solutes in natural freeze tolerant organisms. Improved cryopreservation success will be an essential step in many future areas such as regenerative medicine, seed banking, or stem cell technology. To achieve this, we will need to further improve our understanding of cryobiology, where better and safer CPAs will be key requirements.
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Feeding Ecology and Dietary Flexibility of Colobus angolensis palliatus in Relation to Habitat Disturbance
Abstract
Behavioral and dietary flexibility permits primates to survive in variable environments. It is clear that some species cope with habitat disturbance and fragmentation better than others. I examined the dietary flexibility of Colobus angolensis palliatus by studying three groups inhabiting structurally distinct ranges in Kenya's Diani Forest. I predicted that the two groups inhabiting more disturbed areas would have reduced food availability and would respond by increasing dietary diversity and consuming greater proportions of lianas and exotic plant species compared to the group inhabiting the more intact area. Forest composition and overall plant part availability differed among home ranges; however, group diets did not differ in their proportions of different plant parts, nor did groups select plant parts in proportion to their availability. Diets differed dramatically with regard to species-specific plant parts, i.e., mean monthly dietary overlap among groups = 10.4%. Contrary to my predictions, all three groups exhibited considerable dietary diversity, i.e., 63–76 plant species, and relied heavily on lianas, i.e., 20.8–38.4% of the diet, and exotic plant species, i.e., 30.1–40.3% of the diet. The presence of exotic plant species in all three ranges suggests that even the most intact areas of the Diani Forest are perturbed and should be classified along a spectrum of habitat disturbance rather than intact vs. degraded. Nonetheless, this study emphasizes that diets can vary considerably among groups living in the same forest, and this degree of dietary flexibility likely enables C. a. palliatus to survive within increasingly disturbed habitats.
http://ift.tt/2qNoyPg
A comparative decomposition study using still born piglets and leaf litter from a deciduous forest
A cadaver is an energy resource, which plays a role in nutrient cycling with the release of numerous compounds such as acetic acid, amino acids and propionic acid, into the surrounding soil [1,2]. In particular, its decomposition is often described as a complex process that is attributed to microbial, vertebrate and invertebrate scavenger metabolic activities, which impacts the surrounding environmental microbiota [1,3]. Advancements in molecular microbial ecology techniques have enabled researchers to study the epinecrotic, necrobiome and thanatomicrobiome communities in these complex interactions within the novel forensic ecogenomics discipline [4,5,6].
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Down-regulation of ARID1A is sufficient to initiate neoplastic transformation along with epigenetic reprogramming in non-tumorigenic endometriotic cells
The chromatin remodeler AT-Rich Interactive Domain 1A (ARID1A) is frequently mutated in ovarian clear cell carcinoma (OCCC) and endometriosis precursor lesions. Here, we show that knocking down ARID1A in an immortalized endometriosis cell line is sufficient to induce phenotypic changes indicative of neoplastic transformation as evidenced by higher efficiency of anchorage-independent growth, increased propensity to adhere to collagen, and greater capacity to invade basement membrane extract in vitro.
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One pathogen two stones: are Australian tree frog antimicrobial peptides synergistic against human pathogens?
Abstract
Antimicrobial peptides (AMPs) may act by targeting the lipid membranes and disrupting the bilayer structure. In this study, three AMPs from the skin of Australian tree frogs, aurein 1.2, maculatin 1.1 and caerin 1.1, were investigated against Gram-negative Escherichia coli, Gram-positive Staphylococcus aureus, and vesicles that mimic their lipid compositions. Furthermore, equimolar mixtures of the peptides were tested to identify any synergistic interactions in antimicrobial activity. Minimum inhibition concentration and minimum bactericidal concentration assays showed significant activity against S. aureus but not against E. coli. Aurein was the least active while maculatin was the most active peptide and some synergistic effects were observed against S. aureus. Circular dichroism experiments showed that, in the presence of phospholipid vesicles, the peptides transitioned from an unstructured to a predominantly helical conformation (>50%), with greater helicity for POPG/TOCL compared to POPE/POPG vesicles. The helical content, however, was less in the presence of live E. coli and S. aureus, 25 and 5%, respectively. Equimolar concentrations of the peptides did not appear to form greater supramolecular structures. Dye release assays showed that aurein required greater concentration than caerin and maculatin to disrupt the lipid bilayers, and mixtures of the peptides did not cooperate to enhance their lytic activity. Overall, aurein, maculatin, and caerin showed moderate synergy in antimicrobial activity against S. aureus without becoming more structured or enhancement of their membrane-disrupting activity in phospholipid vesicles.
http://ift.tt/2pT7dVk
Co-chaperoning by amyloid-forming proteins: cystatins vs. crystallins
Abstract
Cystatins and crystallins are both neuroprotective proteins. Except for their function as cysteine cathepsins inhibitors, cystatins are Aβ binding proteins and presumably protect neurons from intracellular Aβ and extracellular Aβ plaques. Pathological mutations of cystatin C cause amyloid angiopathy. Crystallins, known as small heat shock proteins, bind not only Aβ peptide but also other crystallins in the eye lens and prevent their aggregation. Mutations in crystallins cause cataracts and myopathies. Cross-interactions between amyloidogenic proteins, intrinsically disordered and folded proteins, can also occur. I term the nonspecific binding between amyloidogenic proteins and peptides "co-chaperoning." A wide range of other Aβ binding proteins exist, such as catalase, lysozyme, β-lactoglobulin and some other abundant proteins found in plasma.
http://ift.tt/2pS5Xnf
Spontaneous CSF rhinorrhea from the trigeminal canal in an adolescent
We report a case of a seventeen-year old, healthy, non-obese young woman who presented with retro-orbital headaches and metallictasting, left-sided rhinorrhea. Computed tomography revealed a defect along the medial wall of the canal of V2 within a well-pneumatized lateral recess of the left sphenoid sinus. Prior imaging obtained 4 years earlier in the context of nasal trauma showed no such defect - thus lending support for the arachnoid granulation hypothesis of spontaneous CSF leaks from the sphenoid sinus.
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Non-invasive methods to maintain cervical spine position after pediatric tracheal resections
To present our experience with two methods of neck stabilization after pediatric tracheal resection with primary anastomosis as possible alternatives to the traditional chest-chin suture.
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Cervical spine bone density in young healthy adults as a function of sex, vertebral level and anatomic location
Abstract
Purpose
Bone mineral density (BMD) measured using quantitative computed tomography (QCT) has been shown to correlate with bone mechanical properties. Knowledge of BMD within specific anatomic regions of the spine is valuable to surgeons who must secure instrumentation to the vertebrae, to medical device developers who design screws and disc replacements, and to researchers who assign mechanical properties to computational models. The objective of this study was to comprehensively characterize BMD in the cervical spine of young healthy adults.
Methods
QCT was used to determine BMD in the cervical spines of 31 healthy adults (age 20–35). Subject-specific 3D models of each vertebra were created from CT scans, and anatomic regions of interest were identified in each bone (C1: 3 regions; C2: 9 regions, C3–C7: 13 regions). Statistical tests were performed to identify differences in BMD according to vertebral level, anatomic regions within vertebrae, and sex.
Results
BMD varied significantly among vertebral levels and among anatomic regions within each vertebra. Females had higher BMD than males (p = .041) primarily due to higher BMD in the posterior regions of each vertebra.
Conclusions
These data can serve as a baseline to identify BMD changes in older and symptomatic patients. This data set is also the first report of volumetric bone density within different anatomic regions of the atlas and axis of the cervical spine. The finding of higher BMD in females is in agreement with the previous QCT results but contradicts DEXA results that are known to be dependent upon bone size.
http://ift.tt/2qbMrTF
Review of radiological classifications of pancreatic cancer with peripancreatic vessel invasion: are new grading criteria required?
Abstract
Pancreatic cancer is mainly diagnosed at an advanced stage when adjacent vessel invasion is present; however, radical resection is potentially curative for selected patients with adjacent vessel invasion. Therefore, accurately judging the resectability of patients with adjacent vessel invasion represents a crucially important step in diagnosis and treatment. Currently, decisions regarding resectability are based on imaging studies, commonly contrast computed tomography (CT). Several radiological classifications have been published for vascular infiltration in pancreatic cancer. However, radiologists always formulate these CT grading systems according to their own experience, resulting in different judgment methods and parameters. And it is controversial in evaluating performance and clinical application. Besides, the conventional CT grading systems mainly focus on the evaluation of vessel invasion so as to less on the outcome of patient evaluation. In this review, we summarize the mainstream CT grading systems for vascular invasion in pancreatic cancer, with the aim of improving the clinical value of CT grading systems for predicting resectability and survival.
http://ift.tt/2plSyki
First step to facilitate long-term and multi-centre studies of shear wave elastography in solid breast lesions using a computer-assisted algorithm
Abstract
Purpose
Shear wave elastography (SWE) visualises the elasticity of tissue. As malignant tissue is generally stiffer than benign tissue, SWE is helpful to diagnose solid breast lesions. Until now, quantitative measurements of elasticity parameters have been possible only, while the images were still saved on the ultrasound imaging device. This work aims to overcome this issue and introduces an algorithm allowing fast offline evaluation of SWE images.
Methods
The algorithm was applied to a commercial phantom comprising three lesions of various elasticities and 207 in vivo solid breast lesions. All images were saved in DICOM, JPG and QDE (quantitative data export; for research only) format and evaluated according to our clinical routine using a computer-aided diagnosis algorithm. The results were compared to the manual evaluation (experienced radiologist and trained engineer) regarding their numerical discrepancies and their diagnostic performance using ROC and ICC analysis.
Results
ICCs of the elasticity parameters in all formats were nearly perfect (0.861–0.990). AUC for all formats was nearly identical for \({E}_{\mathrm{max}}\) and \({E}_{\mathrm{mean}}\) (0.863–0.888). The diagnostic performance of SD using DICOM or JPG estimations was lower than the manual or QDE estimation (AUC 0.673 vs. 0.844).
Conclusions
The algorithm introduced in this study is suitable for the estimation of the elasticity parameters offline from the ultrasound system to include images taken at different times and sites. This facilitates the performance of long-term and multi-centre studies.
http://ift.tt/2pSLrRq
La leptospirose en Guyane française et sur le bouclier des Guyanes. État des connaissances en 2016
Résumé
La leptospirose est une zoonose cosmopolite causée par les bactéries du genre Leptospira. Si sa répartition est vaste sur le globe, le climat chaud et humide de la zone intertropicale est particulièrement propice à son expansion. Dans la plupart des départements et territoires français d'outremer, la leptospirose est considérée comme un problème de santé publique. En Guyane, département français situé au nord-est de la forêt amazonienne, elle est considérée comme rare. L'objectif de cette revue est de faire l'état des lieux des connaissances sur la leptospirose humaine et animale en Guyane française et dans les pays environnants. Une recherche exhaustive a été conduite, à travers la littérature médicale indexée et informelle en français, anglais, espagnol et portugais. Ainsi, respectivement dix et quatre publications ont pu être identifiées sur la leptospirose humaine et animale en Guyane, publiées entre 1940 et 1995, sous formes de cas cliniques ou de séries de cas. Les publications concernant cette maladie dans les autres pays du plateau des Guyanes, Venezuela oriental, Guyana, Suriname, et État brésilien de l'Amapá, étaient également rares voire inexistantes. En revanche, les données récentes du centre national de la leptospirose français ont montré une augmentation récente et brutale du nombre de cas dans le département, probablement en partie due à la mise en place d'outils diagnostiques tels que la sérologie IgM Elisa. Il est en fait probable que la leptospirose soit une maladie négligée dans la région, du fait de l'absence d'outils diagnostiques rapidement disponibles, de la méconnaissance des cliniciens de cette pathologie et de l'existence de nombreux autres pathogènes à présentation clinique similaire (paludisme, arboviroses, fièvre Q, toxoplasmose amazonienne). La mise en place d'études de plus grande ampleur sur la leptospirose animale et humaine est nécessaire et urgente pour connaître le véritable poids de cette maladie dans notre région.
http://ift.tt/2p7UPUl
Once More, with Feeling! Reply to Ainslie
Abstract
Ainslie's contribution offers a useful refinement of his powerful model of intertemporal bargaining. However, he focuses mostly on the cognitive mechanisms of choice. I suggest that these interact with emotional, personality, and developmental dynamics that cannot be ignored, either psychologically or neurally.
http://ift.tt/2qMUBip
Searching for Norms to Violate. Reply to Henden & Gjelsvik
Abstract
Although I reject neuronormativity -- an idea central to the Brain Disease Model of Addiction (BDMA) -- Henden and Gjelsvik argue that the disease definition might refer to normativity in nonneural domains. They profess that a cognitive dysfunction (e.g., impaired response inhibition), or a mismatch of evolutionary intentions, could also qualify as norm violations, thus legitimizing the disease label. The need for dividing lines is questioned as well. I rebut these criticisms in turn, but I must admit they are thought provoking.
http://ift.tt/2pNTfW7
Primary cardiac diffuse B cell lymphoma presenting with right heart failure: a case report and review of literature
Abstract
Primary cardiac lymphoma (PCL) is one of the rarest tumours of the heart, which is typical of non-Hodgkin's type and involves only the heart and pericardium. It accounts for 1.3% of all cardiac tumours, and diffuse B cell lymphomas are more frequent type of PCL. A 52-year-old male was admitted to our department with features of right sided heart failure, and 2D echocardiography and colour Doppler study revealed right atrial myxoma. The patient underwent surgery on cardiopulmonary bypass. Intraoperatively, there was a large, lobulated, firm mass of size 5 cm × 4 cm × 3 cm arising from the lateral wall of the right atrium involving the roof and extending up to the superior vena cava. Histopathology study confirmed the diagnosis of diffuse B cell lymphoma. The patient was treated with chemotherapy post-operatively. PCL, although a rare variety of cardiac tumour, must be considered as a differential diagnosis in elderly patients presenting with cardiac failure. Therefore, proper evaluation is mandatory and timely management is required in such cases.
http://ift.tt/2pltwBL
IUGR induced by maternal chronic inflammation: long-term effect on offspring’s ovaries in rat model—a preliminary report
Abstract
Purpose
Excess maternal inflammation and oxidative stress while in utero have been known to affect gross fetal development. However, an association between the inflammatory process in utero and the effects on ovarian development and future fertility has not yet been demonstrated. This study focused on LPS-induced chronic inflammation in early pregnancy and its effect on ovarian development and reserves of the offspring, using a rat model. Our aim was to determine whether maternal inflammation in utero disturbs reproductive system development in the offspring, given that maternal inflammation and oxidative stress has been shown to affect gross fetal development.
Methods
Prospective case control rat model. Sprague–Dawley pregnant rats (n = 11) received intraperitoneal lipopolysaccharide (LPS group) (50 µg/kg bodyweight) or saline solution (control group) on day 14, 16, and 18 of gestation. Pups were delivered spontaneously. At 3 months, female offspring were weighed and killed. Ovaries were harvested for (1) follicle count using hematoxylin and eosin staining, (2) apoptosis: ovaries were stained for caspase, and (3) serum CRP and AMH levels were determined.
Results
Birth weights of pups were significantly lower in the LPS group compared to the control group (6.0 ± 0.6 vs. 6.6 ± 0.4 gr; P = 0.0003). The LPS group had fewer preantral follicles, and increased intensity of Caspase 3 staining (510 vs. 155.5 u; P = 0.007). AMH levels were significantly lower in the LPS group (4.15 ± 0.46 vs 6.08 ± 1.88 ng/ml; P = 0.016). There was no significant difference in the CRP and MCP-1 levels between the two groups.
Conclusions
Chronic maternal inflammation induced intrauterine growth restriction in offspring and a decrease in the proportion of follicles. This change might be due to premature apoptosis. These preliminary results suggest that maternal inflammation has a detrimental effect on the development of the female reproductive system of the offspring and thus, future fertility.
http://ift.tt/2pky5wi
High-resolution ultrasound of the midfoot: sonography is more sensitive than conventional radiography in detection of osteophytes and erosions in inflammatory and non-inflammatory joint disease
Abstract
This study aimed to compare the diagnostic value of ultrasonography to conventional radiography in detecting osteophytes and erosions in the midfoot joints in patients suffering from inflammatory and non-inflammatory joint disease. Patients with current foot radiographs were included and stratified in two cohorts: inflammatory and non-inflammatory joint disease. The ten midfoot joints of each foot were evaluated by conventional radiography assessing the presence of osteophytes and erosions and by ultrasonography determining the presence of osteophytes, erosions, and joint effusion. Power Doppler activity was scored semi-quantitatively from 0 to 3. A total of 2445 joints in 124 patients (90 with inflammatory joint disease, 34 with non-inflammatory joint disease) were assessed. Ultrasonography detected significantly more osteophytes than conventional radiography (344; 14.1% vs. 13; 0.5%), as well as more erosions (60; 2.5% vs. 3; 0.1%). There was weak agreement between the two modalities (κ-statistic 0.029–0.035). Power Doppler ultrasonography demonstrated no significant difference in hyperperfusion comparing patients with inflammatory joint disease and non-inflammatory joint disease. Ultrasonography of the midfoot is more sensitive than conventional radiography in the detection of osteophytes and erosions in patients suffering from inflammatory and non-inflammatory joint disease. Thus, midfoot ultrasonography may be a useful tool in the diagnosis of joint diseases as rheumatoid arthritis and osteoarthritis.
http://ift.tt/2phs2I9
Model study of combined electrical and near-infrared neural stimulation on the bullfrog sciatic nerve
Abstract
This paper implemented a model study of combined electrical and near-infrared (808 nm) neural stimulation (NINS) on the bullfrog sciatic nerve. The model includes a COMSOL model to calculate the electric-field distribution of the surrounding area of the nerve, a Monte Carlo model to simulate light transport and absorption in the bullfrog sciatic nerve during NINS, and a NEURON model to simulate the neural electrophysiology changes under electrical stimulus and laser irradiation. The optical thermal effect is considered the main mechanism during NINS. Therefore, thermal change during laser irradiation was calculated by the Monte Carlo method, and the temperature distribution was then transferred to the NEURON model to stimulate the sciatic nerve. The effects on thermal response by adjusting the laser spot size, energy of the beam, and the absorption coefficient of the nerve are analyzed. The effect of the ambient temperature on the electrical stimulation or laser stimulation and the interaction between laser irradiation and electrical stimulation are also studied. The results indicate that the needed stimulus threshold for neural activation or inhibition is reduced by laser irradiation. Additionally, the needed laser energy for blocking the action potential is reduced by electrical stimulus. Both electrical and laser stimulation are affected by the ambient temperature. These results provide references for subsequent animal experiments and could be of great help to future basic and applied studies of infrared neural stimulation (INS).
http://ift.tt/2phprxH
Effect of the surface on the internal structure of CdSe crystal lattice based on molecular dynamics simulations
Abstract
The results of molecular dynamics (MD) simulations of CdSe crystals terminated by low-index atomic planes, (100), (110) and (111), are presented. The effect of the crystal termination on the atomic arrangement (interatomic distances) at the surface and underneath the surface is examined. It is shown that the crystal lattice is distorted in lateral and normal directions to the depth of up to about 2 nm from the surface. The exact characteristic of the changes of interatomic distances is specific to the type of the atomic plane terminating the crystal lattice. At some surfaces, the very last monoatomic layer loses the long-range ordering and becomes quasi amorphous. The atoms group into randomly distributed pairs or short linear groups.
Graphical abstract
http://ift.tt/2pkN8pE
Nanosafety practices: results from a national survey at research facilities
Abstract
The exposure to engineered nanomaterials (ENMs) is a new emerging risk at work due to an increase in the number of workers potentially exposed to them and the current lack of data on their health and safety risks. This paper reports the findings of a survey designed to study the safety practices employed by workers in Spanish research facilities performing tasks involving the use of ENMs at research level. A questionnaire pretested and validated by an expert panel was sent by e-mail to the target audience. The 425 surveys completed show that most of the respondents handled up to 5 different ENMs, in suspension, in small amounts during short periods of exposure. The implementation of common hygienic practices, such as the use of protection for hands and the implementation of fume hoods, is widely indicated. The selection of the preventive and protective measures does not depend on the characteristics of ENMs handled. Also, the risks posed by ENMs are widely ignored. Besides the performance of risk assessment, hygienic monitoring and the conducting of a specific health surveillance are practically non-existent although some accidents relating to ENMs were identified. In conclusion, workers' exposure to ENMs seems to be low. Even though the best practices and preventive and protective measures reported were employed, most of the respondents could not be correctly protected. Moreover, workers do not associate the measures implemented with the nanorisks. Finally, there is a lack of proactive action underway to protect the workers, and concerns about safety are weakly evidenced.
http://ift.tt/2pkU1al
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