In the diagnosis of brain death (BD), computed tomography angiography (CTA) results in some cases show intracranial filling, leading to diagnostic confusion. Because cerebral circulatory arrest commences at the capillary level, we hypothesized that computed tomography perfusion (CTP) would be a more sensitive approach than CTA; therefore, the aim of the study was to compare the sensitivities of CTP and CTA in the diagnosis of BD.
Whole brain CTP was performed in patients in the intensive care unit diagnosed with BD and CTA was derived from CTP datasets. Cerebral blood flow (CBF) and volume (CBV) were calculated in all brain regions. The CTP findings were interpreted as being consistent with a diagnosis of BD (positive) when CBF and CBV in all regions of interest (ROIs) were below 10 ml/100 g/min and 1.0 ml/100 g, respectively. The CTA findings were interpreted using a 4-point grading system.
A total of 50 patients were included in the study. The CTP results revealed CBF from 0.00 to 9.98 ml/100 g/min (mean, 1.98 ± 1.68 ml/100 g/min) and CBV from 0.00 to 0.99 ml/100 g (mean, 0.14 ± 0.12 ml/100 g) and were thus interpreted as positive in all 50 patients. In contrast, the CTA results suggested 7 negative cases, providing a sensitivity of 86%. The difference between the CTP and CTA sensitivity results for the diagnosis of BD was statistically significant (p = 0.006).
Whole brain CTP may potentially be a feasible and highly sensitive test for diagnosing BD: therefore, performing CTP in combination with CTA in cases when CTA results are negative for BD could increase the sensitivity of CTA.
Publication date: Available online 15 November 2017
Source:Oral Surgery, Oral Medicine, Oral Pathology and Oral Radiology
Author(s): N. Gustafsson, J. Ahlqvist, U. Näslund, P. Wester, K. Buhlin, A. Gustafsson, E. Levring Jäghagen
ObjectiveThe aim of this case-control study was to investigate whether subjects with a first myocardial infarction (MI) had a higher prevalence of calcified carotid artery atheromas (CCAAs) in panoramic radiographs (PRs) than age, gender, and residential area matched controls without MIs.Study designSix hundred ninety-six cases with a first MI and 696 controls, were included in this sub-study of the Swedish multicentre PAROKRANK study. All subjects had PRs that were evaluated for CCAAs.ResultsThe prevalence of CCAAs detected by PR was 33.8% (235/696) in cases and 27.6% (192/696) in controls (odds ratio [OR]: 1.24, 95% CI: 1.04-1.44; p=0.012). Among males, 32.7% (184/562) of cases and 26.5% (149/562) of controls displayed CCAAs in PRs (OR: 1.24, 95% CI: 1.03-1.48; p=0.022). Among both genders, bilateral CCAAs were significantly more common among cases than among controls (p=0.002).ConclusionCases, i.e. subjects with recent MIs, had a significantly higher prevalence of CCAAs in PRs compared to controls, i.e. subjects without MIs. This difference between groups was more pronounced for bilateral CCAAs. These findings supported the contention that CCAA detection could serve as a risk indicator for future MIs.
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Publication date: Available online 15 November 2017
Source:Oral Surgery, Oral Medicine, Oral Pathology and Oral Radiology
Author(s): Emre Tosun, Canseda Avağ, Özgür Başlarlı, Serkan Kiriş, Anıl Öztürk, Murat Akkocaoğlu
ObjectiveThe aim of this study was to compare the peri-implant bone level changes of implants placed during and 3 months after bone grafting from the iliac crest.Study DesignA total of 103 implants were placed; 42 during the grafting, and 61 three months after the grafting procedure. All patients were grafted with iliac bone from the anterior superior iliac crest. Bone resorption was evaluated with cone-beam computed tomography, in all patients, at their last control visit. Periodontal health was assessed via the gingival and plaque indices and pocket depths around the dental implants.ResultsMean bone resorption values at the buccal, lingual, mesial, and distal sides of the implants were 1.08 mm, 0.36 mm, 0.30 mm, and 0.25 mm in the delayed group, and 1.87 mm, 1.25 mm, 0.92 mm, and 1.23 mm in the simultaneous group, respectively; the differences between the groups were significant. There were no significant between-group differences in the gingival or plaque indices, or pocket depths. The mean follow-up period was 29 months.ConclusionFor reconstructing atrophic jaws, bone grafting from the iliac crest and implant placement after 3 months is a reliable technique with a high success rate and less bone resorption.
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Publication date: Available online 15 November 2017
Source:Oral Surgery, Oral Medicine, Oral Pathology and Oral Radiology
Author(s): L. Rúa Gonzálvez, L. de Villalaín Álvarez, A. Novoa Gómez, J.C. de Vicente Rodríguez, I. Peña González
Purpose: Small intraoral defects are usually reconstructed using skin autografts. However, the goal of this research was to describe an alternative to the classical techniques using artificial dermis (Integra®) in the reconstruction of these types of injuries. Materials and Methods: Four patients with small intraoral lesions in different locations underwent resection. The created defects were covered with a bilayer of Integra®; then, a chlorhexidine stent cure (Laboratorios Salvat, Barcelona, Spain) was applied. The patients were followed-up daily during the first week to detect any signs of infection, dehiscence or loss of the lamina. Thereafter, they were followed-up once per week for one month. Results: None of the patients presented with infections or a loss of the dermis. When the silicon sheet was detached, granulation tissue was detected, with complete re-epithelialization of the lesion in the postsurgical third through fourth weeks. Conclusion: The use of the Integra® allowed for the rapid reconstruction of slight intraoral defects, while preventing the morbidity associated with classical techniques. In this research, no complications were observed.
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This document presents the consensus recommendations of the Hellenic Stroke Organization which can be of assistance to the treating stroke physicians.
Ophthalmoplegia (OP) can have numerous etiologies and different clinical presentations. Most causes of OP can be narrowed down to specific anatomical locations based on clinical information. The aim of this study was to outline the different categories of diseases encountered in patients with OP, based on the location along the ocular motor pathways, and the most appropriate imaging modality for the given scenarios.
Representative neuroimaging examples of pathological processes causing OP are displayed, sequenced by anatomical location and disease category. Correlations between the clinical presentation and site of pathology with imaging protocol recommendations are also presented.
Diseases affecting ocular movement can be divided into categories including: injuries or diseases of the cerebral hemispheres, midbrain, pons, and cerebellum, ocular motor nerve palsies, intrinsic extraocular muscle diseases and orbital diseases secondarily affecting the extraocular muscles. The cranial nerves responsible for ocular movements can be affected intrinsically or extrinsically along their nuclei, their course in the brainstem, in the cisterns, skull base, cavernous sinuses and orbits. The extraocular muscles can be affected primarily or secondarily by adjacent pathological processes in the orbit. Clinical information can help narrow down the differential diagnoses in terms of anatomical site of involvement and prompt the most appropriate neuroimaging techniques.
By understanding the pathophysiology of OP the neuroradiologist can discuss clinical cases with the referring clinician and determine a timely, accurate method of imaging to achieve the most precise differential diagnosis.
Publication date: Available online 15 November 2017
Source:Radiotherapy and Oncology
Author(s): Joanne S Haviland, Mariella Mannino, Clare Griffin, Nuria Porta, Mark Sydenham, Judith M. Bliss, John R. Yarnold
Background and purposeAdjuvant lymphatic radiotherapy (LNRT) is recommended for selected axillary node positive women with early breast cancer. We investigated whether hypofractionated LNRT is safe combined with similarly-hypofractionated breast/chest wall radiotherapy (RT).Material and methodsThe Standardisation of Breast Radiotherapy (START) pilot, A and B trials randomised women with early breast cancer to schedules of 2.67–3.3 Gy versus 2.0 Gy fractions (control). RT adverse effects were assessed by patients using the EORTC QLQ-BR23 and protocol-specific questions, and by physicians. Rates of arm/shoulder effects were compared between schedules for patients given LNRT.Results864/5861 (14.7%) patients received LNRT (385 START-pilot, 318 START-A, 161 START-B). Prevalences of moderate/marked arm/shoulder effects were low up to 10 years. There were no significant differences between the hypofractionated and control groups for patient- and physician-assessed symptoms in START-A or START-B. In START-pilot, adverse effect rates were higher after 13 fractions of 3.3 Gy, consistent with effects reported in the breast/chest wall (significant for shoulder stiffness, HR 3.07, 95%CI 1.62–5.83, p = 0.001).ConclusionsThe START trial results suggest that appropriately-dosed hypofractionated LNRT is safe in the long-term, according to patient and physician-assessed arm and shoulder symptoms. These findings are consistent with those reported after the same schedules delivered to the breast/chest wall.
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Publication date: Available online 15 November 2017
Source:Construction and Building Materials
Author(s): Wouter Schroeyers, Zoltan Sas, Gergo Bator, Rosabianca Trevisi, Cristina Nuccetelli, Federica Leonardi, Sonja Schreurs, Tibor Kovacs
Scientific data on natural occurring radioactive materials (NORMs) is available in unknown quantities and the data is fragmented over several different sources. The new EU-BSS is regulating the use of NORM in building materials, however a large scale database with country specific information that can support legislators and industry in the assessment of the radiological impact of the use of by-products in construction is missing. Currently the COST Action 'NORM4BUILDING' (2014–2017) is creating such a database using a semi-automated datamining approach. In this paper radiological aspects on by-products that can find application in concrete are discussed based on the database.
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Celebrating 35 Years of the AJNR: November 1982 edition.
AJNR Am J Neuroradiol. 2017 Nov;38(11):2217
Authors:
PMID: 29141999 [PubMed - in process]
Morphometric properties of the latissimus dorsi muscle in human fetuses for flap surgery.
Surg Radiol Anat. 2017 Nov 16;:
Authors: Beger O, Beger B, Uzmansel D, Erdoğan S, Kurtoğlu Z
Abstract
PURPOSE: Although latissimus dorsi (LD) flaps are extensively used in a wide range of interventions, fetus studies on this subject are quite limited. This study aims to obtain detailed information about the morphometric features of LD, thoracodorsal artery (TDA) and nerve (TDN).
METHODS: The study was carried out on both sides of 50 formalin-fixed human fetuses (22 male/28 female) with a mean gestational age of 24.5 ± 4.7 (range 18-36) weeks, which were in the inventory of Anatomy Department of Mersin University Faculty of Medicine. Dimensions of LD, lengths and width of TDA and TDN were measured. Surface area of LD was calculated using digital image analysis software.
RESULTS: All samples had LD muscle. Neither gender nor side-significant differences were observed in relation with the numerical data of LD, TDN and TDA. Linear function of surface area was calculated as "y = - 1767.532 + 114.582 × Age (weeks)". LD was attached directly to the posterior part of iliac crest in 59 of 100 sides meanwhile in the rest 41, it was attached by the thoracolumbar fascia. TDA gave a branch to serratus anterior in 96 cases and 2 branches in 4 cases. TDN passed superficial to TDA in 84 and deep to TDA in 16 samples. TDN had bifurcation in 93, trifurcation in 6 and tetrafurcation in 1 side.
CONCLUSION: Data obtained from this study can be useful for estimating the sizes of LD and related neurovascular structures, especially in neonate surgeries. Linear function of LD surface area can be helpful to design the flap dimensions in newborn surgeries. A throughout knowledge about the branching pattern of TDN and its location-wise relation with TDA should be kept in mind to prevent possible complications during harvesting LD flaps and TDN grafts.
PMID: 29143863 [PubMed - as supplied by publisher]
Extraction, purification of Prostate Specific Antigen (PSA) and establishment of radioimmunoassay system as a diagnostic tool for prostate disorders.
J Immunoassay Immunochem. 2017 Nov 16;:
Authors: Abu-Bakr El-Bayoumy AS, Hessien Keshta AT, Sallam KM, Ebeid NH, Elsheikh HM, Bayoumy BE
Abstract
This study aimed to provide an easy and effective method for extraction and purification of prostate specific antigen (PSA) from human seminal fluid with high quantity (14 mg) and high purity (98%). The obtained PSA was injected into rabbits for production of anti-PSA polyclonal antibody (titer 1/1000), labeled with radioactive iodine-125 for preparation of radioactive PSA tracer (purity 98 ± 1.8% and specific activity 64 ± 1.9 µCi/µg), and used in preparation of PSA standards. All prepared components can be used in PSA immunoassays specially radioimmunoassay (RIA) kit preparation as a diagnostic tool for prostatic diseases.
PMID: 29144195 [PubMed - as supplied by publisher]
Preoperative management in patients with Graves' disease.
Gland Surg. 2017 Oct;6(5):476-481
Authors: Piantanida E
Abstract
Graves' disease is the most frequent cause of hyperthyroidism in iodine-sufficient geographical areas and is characterized by the presence in patients' serum of autoantibodies directed against the thyrotropin receptor (TRAb) that cause overproduction and release of thyroid hormones. Clinical presentation results from both hyperthyroidism and underlying autoimmunity. The diagnosis is based on characteristic clinical features and biochemical abnormalities. If serum thyrotropin (TSH) is low, serum free thyroxine (FT4) and free triiodothyronine (FT3) concentrations should be measured to distinguish between subclinical (with normal circulating thyroid hormones) and overt hyperthyroidism (with increased circulating thyroid hormones). Graves' disease is treated with any of three effective and relatively safe initial treatment options: antithyroid drugs (ATDs), radioactive iodine ablation (RAIU), and surgery. Total thyroidectomy is favored in several clinical situations, such as intolerance, ineffectiveness or recurrence after ATD treatment, radioiodine therapy contraindicated, documented or suspected thyroid malignancy, one or more large thyroid nodules, coexisting moderate-to-severe active Graves' orbitopathy, women planning a pregnancy within 6 months. Whenever surgery is selected as treatment, selection of an expert high-volume thyroid surgeons is fundamental and careful preoperative management is essential to optimize surgical outcomes. Pretreatment with ATDs in order to promptly achieve the euthyroid state is recommended to avoid the risk of precipitating thyroid storm during surgery. For the majority of patients, euthyroidism is achieved after few weeks of ATD treatment. Beta-blockers, such as propranolol, are often added effectively to control hyperthyroid symptoms. Saturated solution of potassium iodide (SSKI) or potassium iodine (Lugol's solution), given for a short period prior to surgery, in order to reduce both thyroid hormone release and thyroid gland vascularity, is beneficial to decrease intra-operative blood loss.
PMID: 29142837 [PubMed]
We report a solid-state 17O (I = 5/2) NMR study of the nitrite ion dynamics in crystalline NaNO2. Variable temperature (VT) 17O NMR spectra were recorded at 3 magnetic fields, 11.7, 14.1, and 21.1 T. The VT 17O NMR data suggest that the 
Un delicato intervento ha salvato la vita a due gemelli nel grembo della madre nonostante un tumore alle ovaie. È successo nella clinica Sanatrix a Napoli dove è stato effettuato il primo intervento in Europa...
Genes, Vol. 8, Pages 330: The HMGA1 Pseudogene 7 Induces miR-483 and miR-675 Upregulation by Activating Egr1 through a ceRNA Mechanism
Genes doi: 10.3390/genes8110330
Authors: Marco De Martino Giuseppe Palma Amalia Azzariti Claudio Arra Alfredo Fusco Francesco Esposito
Several studies have established that pseudogene mRNAs can work as competing endogenous RNAs and, when deregulated, play a key role in the onset of human neoplasias. Recently, we have isolated two HMGA1 pseudogenes, HMGA1P6 and HMGA1P7. These pseudogenes have a critical role in cancer progression, acting as micro RNA (miRNA) sponges for HMGA1 and other cancer-related genes. HMGA1 pseudogenes were found overexpressed in several human carcinomas, and their expression levels positively correlate with an advanced cancer stage and a poor prognosis. In order to investigate the molecular alterations following HMGA1 pseudogene 7 overexpression, we carried out miRNA sequencing analysis on HMGA1P7 overexpressing mouse embryonic fibroblasts. Intriguingly, the most upregulated miRNAs were miR-483 and miR-675 that have been described as key regulators in cancer progression. Here, we report that HMGA1P7 upregulates miR-483 and miR-675 through a competing endogenous RNA mechanism with Egr1, a transcriptional factor that positively regulates miR-483 and miR-675 expression.
Tracheal agenesis is a rare and often lethal congenital defect that leads to airway emergency at birth. Computed tomography (CT) is the modality of choice to evaluate anomalous tracheal anatomy. The absence of spontaneous aeration of the tracheobronchial tree in children with tracheal agenesis makes CT interpretation difficult. We describe a procedure of airway management applied in two newborns with suspected tracheal agenesis. Correct airway management was performed immediately prior to CT examination by airway ventilation, with bag-valve mask alone in one case, and attached to an endotracheal tube placed into the esophagus in the other case. The images allowed for classification of tracheal agenesis. Computed tomography with appropriate airway ventilation is fundamental for the diagnosis of tracheal agenesis.
In the last decades, Danio rerio became one of the most used model organisms in various evo-devo studies devoted to the fin skeletal anatomy and fin-limb transition. Surprisingly, there is not even a single paper about the detailed anatomy of the adult muscles of the five fin types of this species. To facilitate more integrative developmental, functional, genetic, and evolutionary studies of the appendicular musculoskeletal system of the zebrafish and to provide a basis for further comparisons with other fishes and tetrapods, we describe here the identity, overall configuration, and attachments of appendicular muscles in a way that can be easily understood and implemented by non-anatomist researchers. We show that the muscle pattern of the caudal fin is very different from patterns seen in other fins but is very consistent within teleosts. Our observations support the idea of the developmental and evolutionary distinction of the caudal fin and point out that the musculature of the adult zebrafish pectoral and pelvic fins is in general very similar. Both paired fins have superficial and deep layers of abductors and adductors going to all/most rays plus the dorsal and ventral arrectors going only to the first ray. Nevertheless, we noted three major differences between the pelvic and pectoral fins of adult zebrafishes: (i) the pectoral girdle lacks a retractor muscle, which is present in the pelvic girdle – the retractor ischii; (ii) the protractor of the pelvic girdle is an appendicular/trunk muscle, while that of the pectoral girdle is a branchiomeric muscle; (iii) the first ray of the pectoral fin is moved by an additional arrector-3. The anal and dorsal fins consist of serially repeated units, each of which comprises one half-ray and three appendicular muscles (one erector, depressor, and inclinator) on each side of the body. The outermost rays are attachment points for the longitudinal protractor and retractor. Based on our results, we discuss whether the pectoral appendage might evolutionarily be closer to the head than to the pelvic appendage and whether the pelvic appendage might have been derived from the trunk/median fins. We discuss a hypothesis of paired fin origin that is a hybrid of the fin-fold and Gegenbaur's theories. Lastly, our data indicate that D. rerio is indeed an appropriate model organism for the appendicular musculature of teleosts in particular and, at least in the case of the paired fins, also of actinopterygians as a whole.
Sexual dimorphism in the human respiratory system has been previously reported at the skeletal (cranial and thoracic) level, but also at the pulmonary level. Regarding lungs, foregoing studies have yielded sex-related differences in pulmonary size as well as lung shape details, but different methodological approaches have led to discrepant results on differences in respiratory patterns between males and females. The purpose of this study is to analyse sexual dimorphism in human lungs during forced respiration using 3D geometric morphometrics. Eighty computed tomographies (19 males and 21 females) were taken in maximal forced inspiration (FI) and expiration (FE), and 415 (semi)landmarks were digitized on 80 virtual lung models for the 3D quantification of pulmonary size, shape and kinematic differences. We found that males showed larger lungs than females (P < 0.05), and significantly greater size and shape differences between FI and FE. Morphologically, males have pyramidal lung geometry, with greater lower lung width when comparing with the apices, in contrast to the prismatic lung shape and similar widths at upper and lower lungs of females. Multivariate regression analyses confirmed the effect of sex on lung size (36.26%; P < 0.05) and on lung shape (7.23%; P < 0.05), and yielded two kinematic vectors with a small but statistically significant angle between them (13.22°; P < 0.05) that confirms sex-related differences in the respiratory patterns. Our 3D approach shows sexual dimorphism in human lungs likely due to a greater diaphragmatic action in males and a predominant intercostal muscle action in females during breathing. These size and shape differences would lead to different respiratory patterns between sexes, whose physiological implications need to be studied in future research.
Laterally bent dorsal fins are rarely observed in free-ranging populations of cetaceans, contrary to captivity, where most killer whale Orcinus orca adult males have laterally collapsed fins. This topic has been poorly explored, and data/information on its occurrence and possible causes are limited. The present study: (i) undertakes a review of the available information on bent dorsal fins in free-ranging cetaceans, and updates it with new records, (ii) reports on the proportion of bent fins in different study populations, and (iii) discusses possible causes. An empirical approach based on bibliographic research and compilation of 52 new records collected worldwide resulted in a total of 17 species of cetaceans displaying bent dorsal fins. The species with the highest number of records (64%) and from most locations was O. orca. On average, individuals with bent dorsal fins represent < 1% of their populations, with the exception of false killer whales Pseudorca crassidens and O. orca. While line injuries associated with fisheries interactions may be the main cause for P. crassidens, and the vulnerability to health issues caused by the evolutionary enlargement of the fin may be the cause for O. orca adult males, factors contributing to this abnormality for other species are still unclear. The occurrence of bent dorsals could be influenced by a set of variables rather than by a single factor but, irrespective of the cause, it is suggested that it does not directly affect the animals' survivorship. While still rare in nature, this incident is more common (at least 101 known cases) and widespread (geographically and in species diversity) than hypothesized, and is not confined only to animals in captive environments. Investigation into the occurrence of bent fins may be an interesting avenue of research.
Passive hepatic congestion may result from a variety of distinct cardiovascular conditions. Injury to the liver caused by congestion is often asymptomatic and may not be recognized clinically. Diagnosis of congestive hepatopathy is important as it has the potential to cause complications including hepatic fibrosis and development of benign and malignant liver masses. This review will summarize the pathophysiologic mechanisms of congestive hepatopathy and provide both description and examples of its multimodality imaging findings. Examples of alternative disease which may have a similar imaging appearance will be provided. Knowledge regarding the characteristic imaging findings of congestive hepatopathy will allow for its accurate identification. Reviewing both the benefits and limitations of imaging performed to evaluate congestive hepatopathy and its complications will help to avoid pitfalls and enable recommendation of appropriate next steps in diagnostic evaluation.
Transarterial radioembolization is a novel therapy that has gained rapid clinical acceptance for the treatment of hepatocellular carcinoma (HCC). Segmental radioembolization [also termed radiation segmentectomy (RS)] is a technique that can deliver high doses (> 190 Gy) of radiation selectively to the hepatic segment(s) containing the tumor. The aim of this comprehensive review is to provide an illustrative summary of the most relevant imaging findings encountered after radiation segmentectomy. A 62-patient cohort of Child–Pugh A patients with solitary HCC < 5 cm in size was identified. A comprehensive retrospective imaging review was done by interventional radiology staff at our institution. Important imaging findings were reported and illustrated in a descriptive account. For the purposes of completeness, specific patients outside our initial cohort with unique educational imaging features that also underwent segmentectomy were included in this pictorial essay. This review shows that response assessment after RS requires a learning curve with common drawbacks that can lead to false-positive interpretations and secondary unnecessary treatments. It is important to recognize that treatment responses and pathological changes both are time dependent. Findings such as benign geographical enhancement and initial benign pathological enhancement can easily be misinterpreted. Capsular retraction and segmental atrophy are some other examples of unique post-RS response that are not seen in any other treatment.
Pathogens, Vol. 6, Pages 58: The Role of the Mammalian Prion Protein in the Control of Sleep
Pathogens doi: 10.3390/pathogens6040058
Authors: Amber Roguski Andrew Gill
Sleep disruption is a prevalent clinical feature in many neurodegenerative disorders, including human prion diseases where it can be the defining dysfunction, as in the case of the “eponymous” fatal familial insomnia, or an early-stage symptom as in certain types of Creutzfeldt-Jakob disease. It is important to establish the role of the cellular prion protein (PrPC), the key molecule involved in prion pathogenesis, within the sleep-wake system in order to understand fully the mechanisms underlying its contribution to both healthy circadian rhythmicity and sleep dysfunction during disease. Although severe disruption to the circadian rhythm and melatonin release is evident during the pathogenic phases of some prion diseases, untangling whether PrPC plays a role in circadian rhythmicity, as suggested in mice deficient for PrPC expression, is challenging given the lack of basic experimental research. We provide a short review of the small amount of direct literature focused on the role of PrPC in melatonin and circadian rhythm regulation, as well as suggesting mechanisms by which PrPC might exert influence upon noradrenergic and dopaminergic signaling and melatonin synthesis. Future research in this area should focus upon isolating the points of dysfunction within the retino-pineal pathway and further investigate PrPC mediation of pinealocyte GPCR activity.
