Transport and Adsorption of Nano-Colloids in Porous Media Observed by Magnetic Resonance Imaging

Abstract

We use magnetic resonance imaging to follow the adsorption of colloids during their transport through a porous medium (grain packing). We injected successive pulses of a suspension of nanoparticles able to adsorb onto the grains. To get quantitative information we carry out 2D imaging and 1D measurements of the evolution in time of the distribution profile of all particles (suspended or adsorbed) in cross-sectional layers along the sample axis during the flow. For the first injections we observe the 1D profile amplitude progressively damping as particles advance through the sample, due to their adsorption. 2D imaging shows that successive injections finally result in a coverage of grains by adsorbed particles regularly progressing along the sample. The analysis of the results makes it possible to get a clear description of the adsorption process. In our specific case (particle charged oppositely to the adsorption sites) it appears that the particles rapidly explore the pores and adsorb as soon as they encounter available sites on grains, and the surplus of particles goes on advancing in the sample. A further analysis of the profiles makes it possible to distinguish the respective concentration distribution of suspended and adsorbed particles over time at each step of the process.

http://ift.tt/2sTQxjy

Localized Point Mixing Rate Potential in Heterogeneous Velocity Fields

Abstract

Mixing is driven by an interplay between diffusion and flow-induced concentration gradients. Accurately describing the effect of flow heterogeneity on the mixing state of a plume is a challenging problem that has important repercussions on the modeling of plume dilution and chemical reactions. In this technical note, we propose a simple, semi-analytic measure to quantify the local mixing potential at a point based on the local properties of the flow-induced strain. Specifically, it is the trace of the local strain matrix squared, \({\text {Tr}}(\varvec{s}^2)\) , which we demonstrate controls mixing from a point source over small times. Due to its mathematically similar influence to a shear flow on mixing, we propose an ansatz to attempt to use this metric as a predictor for mixing. We test its performance via random walk particle tracking simulations in heterogeneous Darcy flow through lognormal permeability fields. The ansatz appears to work better and better the more heterogeneous the flow, unlike more traditional approaches that rely on weak heterogeneity assumptions. While we cannot rigorously demonstrate why this is, we find it sufficiently promising that it may guide future model development.

http://ift.tt/2sp3L4b

Asymptotic Analysis of Three-Scale Model of pH-Dependent Flows in 1:1 Clays with Danckwerts’ Boundary Conditions

Abstract

The electroremediation process is an efficient method for removing pollutants from clayey soils. We model this process in kaolinite clays considering three scales—nano, micro and macro—under the assumption of a stratified geometry in conjunction with more realistic Danckwerts' boundary conditions imposed at the electrodes. The resulting multiscale model is a coupled system of nonlinear partial differential equations. We derive analytical solutions of the macroscopic equations considering the asymptotic behavior of strongly convective and diffusive regimes. We perform numerical simulations of different scenarios for the electroremediation using the Galerkin finite element method together with a staggered algorithm and the Newton–Raphson method. We validate the accuracy of the proposed algorithm by comparing the discrete solutions to the analytical ones. Finally, we explore and discuss optimal scenarios for the electroremediation process depending on the input values of pH, electrical current, and mass inflow using dimensionless numbers defined from the analytical solutions.

http://ift.tt/2sTQvbq

Exact Solutions for Nonlinear High Retention-Concentration Fines Migration

Abstract

The paper discusses migration of natural reservoir fines lifted by high-rate or low-salinity water injection. The previous papers used linear analytical model, which is valid for low retention of mobilised fine particles in order to determine the model parameters from breakthrough fines concentration and pressure drop across the core during laboratory corefloods. The current work derives exact analytical solutions for the nonlinear case of high retention-concentration fines migration. The solution exhibits uniform profiles of suspended and retained concentrations ahead of the particle front and steady-state retained concentration behind the front. The obtained type curves allow distinguishing between linear and nonlinear fines migration. The laboratory data exhibit close agreement with the nonlinear model predictions, whereas the linear model poorly matches the laboratory data.

http://ift.tt/2soU8CA

Using Resampling Residuals for Estimating Confidence Intervals of the Effective Viscosity and Forchheimer Coefficient

Abstract

Determination of parameters characterizing flows in porous media is a complex inverse problem. It is especially difficult to determine confidence intervals of such parameters. In this note, we develop a method based on utilization of bootstrapping in order to find confidence intervals of model parameters, which are determined by minimizing the discrepancy between model predictions and published experimental results. The discrepancy is characterized by the objective function defined as the sum of squared residuals in the points where experimental measurements are taken. A residual is defined as the difference between the experimentally measured value and the model prediction of this value. We utilized bootstrapping to generate surrogate experimental data by randomly resampling residuals and then adding them back to model predictions. The model parameters that give the best fit with a large number of surrogate data were then determined. By analyzing the histograms of best-fit parameter values, we were able to find confidence intervals for these parameters. We utilized the developed method to determine confidence intervals for the effective viscosity and Forchheimer coefficient.

http://ift.tt/2sTHbEp

Accurate Reconstruction of Porous Materials via Stochastic Fusion of Limited Bimodal Microstructural Data

Abstract

Porous materials such as sandstones have important applications in petroleum engineering and geosciences. An accurate knowledge of the porous microstructure of such materials is crucial for the understanding of their physical properties and performance. Here, we present a procedure for accurate reconstruction of porous materials by stochastically fusing limited bimodal microstructural data including limited-angle X-ray tomographic radiographs and 2D optical micrographs. The key microstructural information contained in the micrographs is statistically extracted and represented using certain lower-order spatial correlation functions associated with the pore phase, and a probabilistic interpretation of the attenuated intensity in the tomographic radiographs is developed. A stochastic procedure based on simulated annealing that generalizes the widely used Yeong–Torquato framework is devised to efficiently incorporate and fuse the complementary bimodal imaging data for accurate microstructure reconstruction. The information content of the complementary microstructural data is systematically investigated using a 2D model system. Our procedure is subsequently applied to accurately reconstruct a variety of 3D sandstone microstructures with a wide range of porosities from limited X-ray tomographic radiographs and 2D optical micrographs. The accuracy of the reconstructions is quantitatively ascertained by directly comparing the original and reconstructed microstructures and their corresponding clustering statistics.

http://ift.tt/2soT7ut

Adverse cardiac events associated with incident opioid drug use among older adults with COPD

Abstract

Purpose

We evaluated whether incident opioid drug use was associated with adverse cardiac events among older adults with chronic obstructive pulmonary disease (COPD).

Methods

This was an exploratory, retrospective cohort study using health administrative data from Ontario, Canada, from 2008 to 2013. Using a validated algorithm, we identified adults aged 66 years and older with non-palliative COPD. Hazard ratios (HR) were estimated for adverse cardiac events within 30 days of incident opioid receipt compared to controls using inverse probability of treatment weighting using the propensity score.

Results

There were 134,408 community-dwelling individuals and 14,685 long-term care residents with COPD identified, 67.0 and 60.6% of whom received an incident opioid. Incident use of any opioid was associated with significantly decreased rates of emergency room (ER) visits and hospitalizations for congestive heart failure (CHF) among community-dwelling older adults (HR 0.84; 95% CI 0.73–0.97), but significantly increased rates of ischemic heart disease (IHD)-related mortality among long-term care residents (HR 2.15; 95% CI 1.50–3.09). In the community-dwelling group, users of more potent opioid-only agents without aspirin or acetaminophen combined had significantly increased rates of ER visits and hospitalizations for IHD (HR 1.38; 95% CI 1.08–1.77) and IHD-related mortality (HR 1.83; 95% CI 1.32–2.53).

Conclusions

New opioid use was associated with elevated rates of IHD-related morbidity and mortality among older adults with COPD. Adverse cardiac events may need to be considered when administering new opioids to older adults with COPD, but further studies are required to establish if the observed associations are causal or related to residual confounding.

http://ift.tt/2u0GXty

Pediatric Cardiology Provider Attitudes About Palliative Care: A Multicenter Survey Study

Abstract

While availability of palliative care consultation for children with advanced heart disease increases, little is known about cardiologist attitudes towards palliative care. We sought to describe perspectives of cardiologists regarding palliative care and to characterize their perceived competence in palliative care concepts. A cross-sectional survey of pediatric cardiologists and cardiac surgeons from 19 pediatric medical centers was performed. Overall response rate was 31% (183/589). Respondents had a median of 18 years of experience since medical school (range 2–49) and most practiced at academic centers (91%). Sixty-percent of respondents felt that palliative care consultations occur "too late" and the majority (85%) agreed that palliative care consultations are helpful. Barriers to requesting palliative care consultation were most frequently described as "referring to palliative care services too early will undermine parents' hope" (45%) and "concern that parents will think I am giving up on their child" (56%). Only 33% of cardiologists reported feeling "very" or "moderately" competent in prognosticating life expectancy while over 60% felt competent caring for children with heart disease around end of life, and nearly 80% felt competent discussing goals of care and code status. Greater perceived competence was associated with subspecialty (heart failure/intensivist vs. other) (OR 3.6, 95% CI 1.6–8.1, p = 0.003) and didactic training (OR 6.27, 95% CI 1.8–21.8, p = 0.004). These results underscore the need for further training in palliative care skills for pediatric cardiologists. Enhancing palliative care skills among cardiologists and facilitating partnership with subspecialty palliative care teams may improve overall care of children with advanced heart disease.

http://ift.tt/2tnggBA

Postnatal Outcomes of Fetal Supraventricular Tachycardia: a Multicenter Study

Abstract

Supraventricular tachycardia (SVT), the most common fetal tachycardia, can be difficult to manage in utero. We sought to better understand predictors of the postnatal clinical course in neonates who experienced fetal SVT. We hypothesized that fetuses with hydrops or those with refractory SVT (failure of first-line SVT therapy) are more likely to experience postnatal SVT. This was a retrospective multicenter cohort study of subjects diagnosed with fetal SVT between 2006 and 2014. Fetuses with structural heart disease were excluded. Descriptive comparative statistics and univariate analysis with logistic regression were utilized to determine factors that most strongly predicted postnatal SVT and preterm delivery. The cohort consisted of 103 subjects. Refractory SVT was found in 37% (N = 38) of the cohort with this group more likely to be delivered prematurely (median = 36 vs. 37.5 weeks, p = 0.04). Refractory SVT did not increase the risk of postnatal SVT (p = 0.09). Postnatal SVT was seen in 61% (N = 63). Of those, 68% (N = 43) had postnatal SVT at ≤2 days of age. Postnatal SVT was associated with a later fetal SVT diagnosis (median = 30 vs. 27.5 weeks, p = 0.006). We found a strong correlation between postnatal SVT and later gestational age at fetal SVT diagnosis. Subjects with refractory SVT or hydrops did not have a higher risk of postnatal SVT. We propose strong consideration for term delivery in the absence of significant clinical compromise. Further studies to assess whether outcomes vary for preterm delivery versus expectant management in those with refractory SVT should be performed.

http://ift.tt/2sTAMJn

Do Work Characteristics Predict Health Deterioration Among Employees with Chronic Diseases?

Abstract

Purpose In our ageing workforce, the increasing numbers of employees with chronic diseases are encouraged to prolong their working lives. It is important to prevent health deterioration in this vulnerable group. This study aims to investigate whether work characteristics predict health deterioration over a 3-year period among employees with (1) chronic diseases, and, more specifically, (2) musculoskeletal and psychological disorders. Methods The study population consisted of 5600 employees aged 45–64 years with a chronic disease, who participated in the Dutch Study on Transitions in Employment, Ability and Motivation (STREAM). Information on work characteristics was derived from the baseline questionnaire. Health deterioration was defined as a decrease in general health (SF-12) between baseline and follow-up (1–3 years). Crude and adjusted logistic regression analyses were performed to investigate prediction of health deterioration by work characteristics. Subgroup analyses were performed for employees with musculoskeletal and psychological disorders. Results At follow-up, 19.2% of the employees reported health deterioration (N = 1075). Higher social support of colleagues or supervisor predicted health deterioration in the crude analyses in the total group, and the groups with either musculoskeletal or psychological disorders (ORs 1.11–1.42). This effect was not found anymore in the adjusted analyses. The other work characteristics did not predict health deterioration in any group. Conclusions This study did not support our hypothesis that work characteristics predict health deterioration among employees with chronic diseases. As our study population succeeded continuing employment to 45 years and beyond, it was probably a relatively healthy selection of employees.

http://ift.tt/2u0JX9B

How Can Supervisors Contribute to the Return to Work of Employees Who have Experienced Depression?

Abstract

Background In Western countries, work disability due to depression is a widespread problem that generates enormous costs. Objective The goal of this study was to determine the types and prevalence of supervisor contributions during the different phases of the return-to-work (RTW) process (before and during the sick-leave absence, and during the RTW preparations) of employees diagnosed with depression. Moreover, we sought to determine which contributions actually facilitate employees' RTW, and to identify the work accommodations most frequently implemented by supervisors at the actual time of their employee's RTW. Methods Telephone interviews were conducted in Québec (Canada) with 74 supervisors working with employees who were already back at work or still on sick leave due to depression. A sub-sample of 46 supervisors who had already taken measures to facilitate their employees' RTW was questioned about the work accommodations implemented. Results Most of the supervisors got along well with their employees before their sick leave and 72% stayed in contact with them during their leave. Nearly 90% of the supervisors encouraged their employees to focus primarily on their recovery before their RTW, but 43% pressured their employees to RTW as soon as possible. Cox regression analyses performed for the entire sample revealed that "the supervisors' intention to take measures to facilitate their employees' RTW" was the only significant predictor of the RTW at the time of the interview. The Kaplan–Meier survival curve showed that 50% of the employees were expected to RTW within the first 8 months of absence. Four of the most frequently implemented work accommodations were actions directly involving the supervisor (i.e. providing assistance, feedback, recognition, and emotional support to the employee). Conclusions This study shed light on the less explored point of view of the supervisor involved in the RTW process of employees post-depression. It highlighted the most frequent and effective supervisor contributions to the process. These results can be used to develop concrete action plans for training supervisors to contribute to the sustainable RTW of employees on sick leave due to depression.

http://ift.tt/2tn37bN

Effect of low-intensity whole-body vibration on bone defect repair and associated vascularization in mice

Abstract

Low-intensity whole-body vibration (LIWBV) may stimulate bone healing, but the involvement of vascular ingrowth, which is essential for bone regeneration, has not been well examined. We thus investigated the LIWBV effect on vascularization during early-stage bone healing. Mice aged 13 weeks were subjected to cortical drilling on tibial bone. Two days after surgery (day 0), mice were exposed daily to sine-wave LIWBV at 30 Hz and 0.1 g peak-to-peak acceleration for 20 min/day (Vib) or were sham-treated (sham). Following vascular casting with a zirconium-based contrast agent on days 6, 9, or 12 and sacrifice, vascular and bone images were obtained by K-edge subtraction micro-CT using synchrotron lights. Bone regeneration advanced more in the Vib group from days 9 to 12. The vascular volume fraction decreased from days 6 to 9 in both groups; however, from days 9 to 12, it was increased in shams, while it stabilized in the Vib group. The vascular volume fraction tended to be or was smaller in the Vib group on days 6 and 12. The vessel number density was higher on day 9 but lower on day 12 in the Vib group. These results suggest that the LIWBV-promoted bone repair is associated with the modulation of vascularization, but additional studies are needed to determine the causality of this association.

http://ift.tt/2tnmhhU

Safety and effectiveness of eribulin in Japanese patients with locally advanced or metastatic breast cancer: a post-marketing observational study

Summary

Background This large-scale study was conducted to evaluate the safety and effectiveness of eribulin for the treatment of inoperable or recurrent breast cancer in real-world settings in Japan. Methods Between July and December 2011, eligible patients with inoperable or recurrent breast cancer receiving eribulin for the first time were centrally registered and observed for 1 year. Eribulin was administered intravenously (1.4 mg/m²) on days 1 and 8 of every 3-week cycle. The primary endpoint was the frequency and intensity of adverse drug reactions (ADRs). Secondary endpoints included overall response rate (ORR) and time to treatment failure (TTF). Results Of 968 patients registered at 325 institutions, 951 and 671 were included in the safety and effectiveness analyses, respectively. In the safety population, ADRs were observed in 841 patients (88.4%). The most common (≥15% incidence) were neutropenia (66.6%), leukopenia (62.4%), lymphopenia (18.4%), and peripheral neuropathy (16.8%). The most common grade ≥ 3 ADRs (>5% incidence) were neutropenia (59.8%), leukopenia (50.5%), lymphopenia (16.1%), and febrile neutropenia (7.7%). In the effectiveness population, ORR was 16.5% (95% confidence interval: 13.7, 19.4). The median TTF was 127 days (95% confidence interval: 120, 134). Conclusions The safety and effectiveness profile of eribulin was consistent with prior studies. Eribulin had a favorable risk-benefit balance when used in real-world clinical settings.

http://ift.tt/2s3UzmD

Primary Squamous Cell Carcinoma of the Pancreas: a Case Report and Literature Review

http://ift.tt/2ukCAsE

Posterior Reversible Encephalopathy Syndrome During Treatment with Aflibercept, 5-Fluorouracil, Leucovorin, and Irinotecan for Metastatic Colorectal Cancer

http://ift.tt/2tngusa

Colon Metastasis, 8 years after Gastrectomy, for Stage I Gastric Cancer

http://ift.tt/2ukY8FJ

Rectal Cancer Surveillance—Recurrence Patterns and Survival Outcomes from a Cohort Followed up Beyond 10 Years

Abstract

Aim

The intensity and duration of surveillance for rectal cancer after surgical resection remain contentious. We evaluated the pattern of recurrences in a rectal cancer cohort followed up beyond 10 years.

Methods

An analysis was performed on a retrospective database of 326 patients with rectal cancer who underwent curative surgical resection from 1999 to 2007. The above study duration was chosen to ensure at least 10 years of follow-up. Data on patient demographics, peri-operative details, and follow-up outcomes were extracted from the database. The pattern of recurrences and investigative modality that detected recurrences was identified. Patients were followed up until either year 2016 or the day of their demise.

Results

Two hundred seventeen patients (66.6%) were male and 109 patients (33.3%) female. Median age was 64 years old. Close to a third of the patients received adjuvant therapy (34%). Among the 326 patients studied, 29.8% of (97/326) patients developed recurrence. 7.7% (25/326) had loco-regional recurrence while 22.1% (72/326) had distant metastasis. Median time to recurrence was 16 months (4–83) and 18 months (3–81), respectively. Computed tomography scan was the best modality to detect both loco-regional and distant recurrences (48% in loco-regional and 41.7% in distant metastasis). The most common site of distant metastasis is the lung (34.7%). The salvage rate for loco-regional and distant recurrences was 52 and 12.5%, respectively.

Conclusion

The predominant pattern of recurrence in rectal cancer is distant disease. Surveillance regimes may need to be altered to increase early detection of distant metastases.

http://ift.tt/2ukQvyW

Acinar Cell Carcinoma of Pancreas: a Case Report and Review of Literature

http://ift.tt/2tmPr0k

Diffuse, Aggressive Metastatic Progression after Minimally Invasive Local Resection of Primary Gastric Synovial Sarcoma: a Case Report and Systematic Review of the Literature

http://ift.tt/2ukQ5ZA

Safety and effectiveness of eribulin in Japanese patients with locally advanced or metastatic breast cancer: a post-marketing observational study

Summary

Background This large-scale study was conducted to evaluate the safety and effectiveness of eribulin for the treatment of inoperable or recurrent breast cancer in real-world settings in Japan. Methods Between July and December 2011, eligible patients with inoperable or recurrent breast cancer receiving eribulin for the first time were centrally registered and observed for 1 year. Eribulin was administered intravenously (1.4 mg/m²) on days 1 and 8 of every 3-week cycle. The primary endpoint was the frequency and intensity of adverse drug reactions (ADRs). Secondary endpoints included overall response rate (ORR) and time to treatment failure (TTF). Results Of 968 patients registered at 325 institutions, 951 and 671 were included in the safety and effectiveness analyses, respectively. In the safety population, ADRs were observed in 841 patients (88.4%). The most common (≥15% incidence) were neutropenia (66.6%), leukopenia (62.4%), lymphopenia (18.4%), and peripheral neuropathy (16.8%). The most common grade ≥ 3 ADRs (>5% incidence) were neutropenia (59.8%), leukopenia (50.5%), lymphopenia (16.1%), and febrile neutropenia (7.7%). In the effectiveness population, ORR was 16.5% (95% confidence interval: 13.7, 19.4). The median TTF was 127 days (95% confidence interval: 120, 134). Conclusions The safety and effectiveness profile of eribulin was consistent with prior studies. Eribulin had a favorable risk-benefit balance when used in real-world clinical settings.

http://ift.tt/2s3UzmD

Knock-Out Serum Replacement and Melatonin Effects on Germ Cell Differentiation in Murine Testicular Explant Cultures

Abstract

Finding robust culture conditions for in vitro maturation (IVM) of male germ cells is still a challenge. Recently, a testis organ culture method, using Knockout Serum Replacement (KSR), was suggested as a promising approach. However, the efficiency of that model is still not optimal. Hence, we have tried to establish the culture conditions in two laboratories, and to improve the reliability of the culture system to generate mature germ cells. Male mice at three days of age were sacrificed. Testes were cut into small pieces which were cultured atop agarose stands, using Minimum Essential Medium alpha supplemented with different supplements; melatonin, Glutamax, and different concentrations of KSR. The results showed that the duration of culture beyond 18 days had an impact on the number of differentiated germ cells. Supplementation with melatonin and Glutamax revealed a positive influence on the efficiency of male germ cell differentiation in vitro. Furthermore, the results confirmed that KSR had a positive effect on germ cell maturation and testosterone production, with a concentration of at least 10%. In conclusion, this study emphasizes the beneficial role of at least 10% KSR in the IVM of germ cells.

http://ift.tt/2tqO5mf

Erratum to: Designing 3-Dimensional In Vitro Oviduct Culture Systems to Study Mammalian Fertilization and Embryo Production

http://ift.tt/2tqJrEH

Tissue Engineered Human Amniotic Membrane Application in Mouse Ovarian Follicular Culture

Abstract

Since folliculogenesis requires a powerful cell–matrix interaction, natural scaffolds seem to be needed for follicular culture. Human amniotic membrane (HAM) offers promise as a support of in vitro ovarian follicular culture. HAM was decellularized with trypsin and EDTA. DNA and histology assays were performed to determine the elimination rate of genomic components. Cyto-biocompatibility of decellular AM (DAM) was verified by the cell viability (MTT) test. The small parts of intact amniotic membrane (IAM) and DAM were coated on the bottom of 96-well and each well was filled with 150 µL of base medium. Mouse primary-secondary (PS) follicles were separated to three groups: 1—culture in base medium (Control), 2—culture on IAM and 3—culture on DAM. Follicular size, morphology, viability, estradiol production and genes expression were evaluated and IAM group showed better growth and development in follicle culture. The viability rate and estradiol production in both experimental groups were statistically higher than the Control. Gdf9, Bmp15 and Cx37 were found to have higher expression levels in IAM group. Also, maximum apoptotic and survival indexes were determined in Control and IAM groups, respectively. Finally, IAM provides a better protective environment for mouse PS follicular culture that can reduce apoptosis level.

http://ift.tt/2tZxbId

Factors Associated with Increased Experience of Postoperative Pain after Laparoscopic Gastric Bypass Surgery

Abstract

Introduction

Patients with high body mass index (BMI), pre-existing pain and young age and women seem to experience more postoperative pain. Few studies have, however, addressed these risk factors amongst obese patients undergoing bariatric surgery.

The aim of the present study was to evaluate risk factors for postoperative pain following laparoscopic gastric bypass surgery.

Methods

In this cohort study, we used data from the PAIN OUT register for postoperative pain during the first 24 h after surgery. Primary outcome measure was severity of pain after surgery. Multivariate analyses were conducted to evaluate BMI, young age, gender and pre-existing pain as independent risk factors for postoperative pain.

Results

We included 192 patients in this study. Younger age (B −0.08, 95%CI −0.11 to −0.05/year; p < 0.001), female gender (B 0.92, 95%CI 0.10–1.75; p = 0.029) and pre-existing pain (B 1.06, 95%CI 0.03–2.09; p = 0.044) were all associated with an increased risk for postoperative pain. In the multivariate analyses, only young age ((adjusted OR 0.95, 95%CI 0.92–0.97/year; p < 0.001) and pre-existing pain (adjusted OR 2.56, 95%CI 1.09–6.00; p = 0.031) remained as independent risk factors for severe postoperative pain.

Conclusion

Younger age and pre-existing pain are associated with severe postoperative pain during the first 24 h after laparoscopic gastric bypass surgery, whereas female gender and high BMI are not.

http://ift.tt/2sSzy0V

Assessing the Actual Clinical Effectiveness of Metabolic/Bariatric Surgery for the Type 2 Diabetes Therapy

http://ift.tt/2snL6WF

Erratum to: Evaluation of Vitamin and Trace Element Requirements after Sleeve Gastrectomy at Long Term

http://ift.tt/2sofTSW

Evolution of Liver Steatosis Quantified by MR Imaging and MR Spectroscopy, in Morbidly Obese Patients Undergoing Sleeve Gastrectomy: Short-Term Outcomes

Abstract

Background

Currently, the standard procedure used to evaluate hepatic steatosis is the liver biopsy. This is an invasive practice that presents inherent risks. Increasing evidence suggests that magnetic resonance imaging (MRI) and MR spectroscopy (MRS) may represent an accurate method to determine the hepatic lipid content. The aim of this study was to evaluate the effect of sleeve gastrectomy on liver steatosis, quantified by MRI and MRS.

Patients and Methods

A prospective observational study of patients undergoing laparoscopic sleeve gastrectomy was performed. All patients underwent a MRI and a MRS study 2 weeks before the intervention and 6 months after the surgery. Anthropometric, biochemical, and radiological parameters were analyzed.

Results

Twenty-three patients were included, 21 females and 2 males, with a mean age of 47.6 ± 10.6 years and mean pre-op BMI 47.6 ± 6.7 Kg/m². Six months after surgery, mean BMI was 32.2 ± 5.1 Kg/m², with a mean excess weight loss of 68.2 ± 18.6%. Mean preoperative hepatic volume was 1999.9 ± 436.2 ml and 6 months after surgery it decreased to 1568 ± 170.3 ml (p = 0.005). Mean preoperative percentage of lipid content was 14.2 ± 15.4% and 6 months after surgery, it decreased to 4.3 ± 3.2% (p = 0.007). A significant reduction of steatosis grade was observed, with disappearance of preoperative steatosis in 54.9% of the patients.

Conclusion

Six months after sleeve gastrectomy, a significant reduction of liver steatosis is observed, as demonstrated by reduction in the percentage of intrahepatocitary lipids and liver volume, determined by MRS and MRI. These imaging techniques can be considered as noninvasive, accurate methods for monitoring liver steatosis in morbidly obese patients undergoing bariatric surgery.

http://ift.tt/2sSKA6s

Another Fatal Outcome with a Biliopancreatic Limb Length of 200 cm with One Anastomosis Gastric Bypass

http://ift.tt/2sSwcLh

Patients’ Preoperative Estimate of Target Weight and Actual Outcome after Bariatric Surgery

Abstract

Background

Evidence about the impact of psychological factors on weight loss after bariatric surgery is scarce. This study explores whether patients' preoperative estimate of target weight influences actual weight loss for different types of bariatric procedures.

Methods

Patients eligible for bariatric surgery were instructed twice on how to calculate their expected target weight. They were divided into three groups based on their percentage excess weight loss (%EWL) and percentage total body weight loss (%TBWL). Weight loss 12 and 24 months after surgery was analyzed for each group and per type of surgery.

Results

Six hundred fifty-six patients participated in this study. Types of surgery performed were the Roux-en-Y gastric bypass (RYGB, 75%), sleeve gastrectomy (SG, 8.1%), REDO-RYGB (12.5%), and laparoscopic adjustable gastric banding (LAGB, 4.4%). Data of 622 and 410 patients were available for analysis at 12 and 24 months, respectively. Surprisingly, 415 patients (63.3%) overestimated their expected weight loss as opposed to our calculation, based on our own historic data. One hundred thirty-four patients (20.4%) estimated their weight loss correctly and 107 patients (16.3%) underestimated their weight loss. There was a significant higher %EWL 12 months after RYGB surgery for patients who overestimated their weight loss compared to those who estimated their weight loss correctly (p = 0.001). After 24 months and for other types of procedures, no statistically significant differences were found between the three groups.

Conclusion

Despite instructions on how to calculate target weight, the majority of patients overestimated their weight loss. Actual %EWL 12 months after RYGB surgery might be influenced by setting a low target weight.

http://ift.tt/2snZUo4

Experience with an Enhanced Recovery After Surgery (ERAS) Program for Bariatric Surgery: Comparison of MGB and LSG in 374 Patients

Abstract

Background

Strategic multidisciplinary protocols for "enhanced recovery after surgery" (ERAS) have demonstrated reductions in length of hospital stay (LOS), morbidity, and costs in conjunction with bariatric procedures.

Methods

We prospectively investigated the effectiveness and safety of an ERAS protocol with laparoscopic omega loop gastric bypass ("mini" gastric bypass, MGB) and LSG in morbidly obese patients.

Results

Average LOS was 1.24 days (range 1-14); 86.1% discharged on day 1; 96.9% by day 2, a value comparable or better than that of other ERAS studies vs standard care according to meta-analysis. Complications 2.9%; readmission 2.1%; reintervention 1.3%.

Conclusion

The program was equally safe with both procedures. Postoperative antithrombotic heparin does not appear necessary in low-risk patients. Bariatric surgical ERAS programs are evolving and not yet standardized.

http://ift.tt/2sSGWtk

Benefits of Long-Term Digital Support Following Bariatric Surgery Incorporating Views from a Patient Advisory Group

http://ift.tt/2snEI1m

Postprandial GLP-2 Levels Are Increased After Biliopancreatic Diversion in Diabetic Individuals with Class I Obesity: a Prospective Study

Abstract

Background

Biliopancreatic diversion (BPD) is a predominantly malabsorptive procedure. Glucagon-like peptide 2 (GLP-2) plays predominantly trophic effects on the gut. A significant increase in GLP-2 after BPD in rats was previously observed, but there are no studies investigating the effect of BPD in GLP-2 levels in humans.

Objective

The aim of this study is to evaluate the influence of BPD on the release of GLP-2.

Methods

This is a prospective cohort study that evaluated diabetic individuals with class I obesity which underwent BPD (Scopinaro operation) and were followed up for 12 months. Of 12 individuals, four did not comply with the proposed follow-up and were excluded from the analysis. GLP-2 levels were determined by means of an enzyme-linked immunosorbent assay (ELISA), and we collected serial lab samples through a standard meal tolerance test (MTT) in the immediate preoperative period and 12 months after surgery.

Results

During standard MTT, we observed significant increases of GLP-2 levels from 15 to 60 min (respectively, at 15 min, 5.7 ± 3.4 versus 12.4 ± 4.3, p = 0.029; 30 min, 6 ± 3.5 versus 14.6 ± 3.9; p = 0.004; 45 min, 5.6 ± 4.1 versus 12.6 ± 5.2, p = 0.013; 60 min, 5.8 ± 2.9 versus 10.6 ± 5.6, p = 0.022); then it began to gradually decrease to levels close to the basal.

Discussion

Our findings have confirmed that there is a significant increase in GLP-2 levels after BPD in humans. GLP-2 plays a number of roles which may be adaptive, compensatory, and beneficial in the context of BPD. The clinical implications of this finding remain to be completely understood.

http://ift.tt/2sSAQsS

Are Obese Patients at an Increased Risk of Pelvic Floor Dysfunction Compared to Non-obese Patients?

Abstract

Purpose

Factors associated with increased intra-abdominal pressure such as chronic cough, morbid obesity, and constipation may be related to pelvic floor dysfunction. In this study, we compared anorectal manometry values and clinical data of class II and III morbidly obese patients referred to bariatric surgery with that of non-obese patients.

Methods

We performed a case-matched study between obese patients referred to bariatric surgery and non-obese patients without anorectal complaints. The groups were matched by age and gender. Men and nulliparous women with no history of abdominal or anorectal surgery were included in the study. Anorectal manometry was performed by the stationary technique, and clinical evaluation was based on validated questionnaires.

Results

Mean age was 44.8 ± 12.5 years (mean ± SD) in the obese group and 44.1 ± 11.8 years in the non-obese group (p = 0.829). In the obese group, 65.4% of patients had some degree of fecal incontinence. Mean squeeze pressure was significantly lower in obese than in non-obese patients (155.6 ± 64.1 vs. 210.1 ± 75.9 mmHg, p = 0.004), and there was no significant difference regarding mean rest pressure in obese patients compared to non-obese ones (63.7 ± 23.1 vs. 74.1 ± 21.8 mmHg, p = 0.051). There were no significant differences in anorectal manometry values between continent and incontinent obese patients.

Conclusions

The prevalence of fecal incontinence among obese patients was high regardless of age, gender, and body mass index. Anal squeeze pressure was significantly lower in obese patients compared to non-obese controls.

http://ift.tt/2sogqo8

Treatment Success: Investigating Clinically Significant Change in Quality of Life Following Bariatric Surgery

Abstract

Background

One of the most important outcomes following bariatric surgery is an improvement in health-related quality of life (QOL). This study aimed to explore what degree of weight loss is required after bariatric surgery in order to achieve a clinically significant change in QOL from pre-surgery to 4 to 5 years after surgery.

Methods

Participants were assessed prior to having surgery (N = 280) and were invited to participate in a follow-up study 4 to 5 years after surgery. Sixty-seven of the original participants agreed to take part and completed a Web-based survey, which included the Impact of Weight on Quality of Life-Lite (IWQOL-Lite) questionnaire. Several analyses were conducted to examine the association between weight loss and clinically significant change in QOL.

Results

Mean age was 48.13 ± 10.37 years, 51 (76%) were female, 62 (92.5%) Caucasian, and mean baseline body mass index (BMI) was 41.11 ± 6.03 kg/m². The mean percent of excess weight loss (EWL) was 46% (17% total weight loss), and 64% (n = 43) achieved a clinically significant change in QOL. The majority of those who lost ≥40% EWL had a clinically significant change in QOL, and their odds of achieving this change were 2.81 times higher than those that did not.

Conclusions

Results indicated that an EWL of ≥40% may be sufficient for the majority of patients to achieve clinically significant change, but that ≥50% is a better predictor of clinically significant change.

http://ift.tt/2sSzuOJ

Preserved Fat-Free Mass after Gastric Bypass and Duodenal Switch

Abstract

Background

Concerns for the possibility of an excessive loss of fat-free mass (FFM) and resting metabolic rate (RMR) after bariatric surgery, such as Roux-en-Y gastric bypass (RYGB) and duodenal switch (BPD/DS), have been raised.

Objectives

This study aims to examine body composition and RMR in patients after RYGB and BPD/DS and in non-operated controls.

Methods

Body composition and RMR were studied with Bod Pod and indirect calorimetry in weight-stable RYGB (n = 15) and BPD/DS patients (n = 12) and compared with non-operated controls (n = 17). All patients were 30–55 years old and weight stable with BMI 28–35 kg/m².

Results

FFM% was 58% (RYGB), 61% (BPD/DS), and 58% (controls). Body composition did not differ after RYGB and BPD/DS compared to controls, despite 27 and 40% total body weight loss, respectively. No difference in RMR or RMR/FFM was observed (1539, 1617, and 1490 kcal/24 h; and 28.9, 28.4, and 28.8 kcal/24 h/kg).

Conclusion

Weight-stable patients with BMI 28–35 kg/m² after RYGB and BPD/DS have a body composition and RMR similar to that of non-operated individuals within the same BMI interval.

http://ift.tt/2snOSzh

Increased hepatic ABCA1 transporter is associated with hypercholesterolemia in a cholestatic rat model and primary biliary cholangitis patients

Abstract

Hepatic ATP-binding cassette A1 (ABCA1) transporter is the modulator of intrahepatic cholesterol levels via the efflux of cholesterol into plasma. This study aimed to determine the expression of hepatic ABCA1 levels in a cholestatic rat model and patients with primary biliary cholangitis (PBC). A cholesterol efflux study was conducted with Abca1 knock down using siRNA in WIF9 cells. Cholesterol levels in the ABCA1 siRNA cells in the medium were significantly decreased compared with those in controls (P < 0.05). Hepatic ABCA1 mRNA levels were significantly higher in BDL rats than in control rats (P < 0.05). Furthermore, the protein expression level of hepatic ABCA1 was also significantly increased by 200% in BDL rats (P < 0.05). In PBC patients, expression of hepatic ABCA1 mRNA was 2.2-fold higher than that in controls (P < 0.05). The level of hepatic liver X receptor (LXR)β mRNA was correlated with ABCA1 mRNA levels in PBC patients. The expression of hepatic ABCA1 transporter was upregulated in both the cholestatic rat model and PBC patients. Upregulated hepatic ABCA1 may lead to efflux of cholesterol into plasma, thus explaining the mechanism of cholestasis leading to hypercholesterolemia.

http://ift.tt/2tmcSal

Sociodemographic disparities in survival for adolescents and young adults with cancer differ by health insurance status

Abstract

Purpose

To investigate associations of sociodemographic factors—race/ethnicity, neighborhood socioeconomic status (SES), and health insurance—with survival for adolescents and young adults (AYAs) with invasive cancer.

Methods

Data on 80,855 AYAs with invasive cancer diagnosed in California 2001–2011 were obtained from the California Cancer Registry. We used multivariable Cox proportional hazards regression to estimate overall survival.

Results

Associations of public or no insurance with greater risk of death were observed for 11 of 12 AYA cancers examined. Compared to Whites, Blacks experienced greater risk of death, regardless of age or insurance, while greater risk of death among Hispanics and Asians was more apparent for younger AYAs and for those with private/military insurance. More pronounced neighborhood SES disparities in survival were observed among AYAs with private/military insurance, especially among younger AYAs.

Conclusions

Lacking or having public insurance was consistently associated with shorter survival, while disparities according to race/ethnicity and neighborhood SES were greater among AYAs with private/military insurance. While health insurance coverage associates with survival, remaining racial/ethnic and socioeconomic disparities among AYAs with cancer suggest additional social factors also need consideration in intervention and policy development.

http://ift.tt/2tm20ZT

Evaluation of Potentially Prolactin-Related Adverse Events and Sexual Maturation in Adolescents with Schizophrenia Treated with Paliperidone Extended-Release (ER) for 2 Years: A Post Hoc Analysis of an Open-Label Multicenter Study

Abstract

Background

Elevated prolactin levels (hyperprolactinemia) are a frequent adverse effect of antipsychotic medications, especially in young populations. Prolonged hyperprolactinemia may affect sexual functioning and the onset and progression of puberty.

Objective

This study assessed potentially prolactin-related treatment-emergent adverse events (PPRL-TEAEs) and sexual maturation during long-term treatment of adolescents with paliperidone extended-release (ER).

Methods

This post hoc analysis of a 2-year open-label multicenter study (NCT00488319) included patients of either sex aged 12–17 years at study enrollment, diagnosed with schizophrenia (Diagnostic and Statistical Manual of Mental Disorders, 4th edition [DSM-IV]) for ≥1 year, who had received one or more adequate antipsychotic treatment prior to enrollment but had not responded sufficiently. Patients were initially treated with 6 mg/day paliperidone ER and further titrated between 1.5 and 12 mg/day based on clinical response and tolerability. The primary objective was to determine the relationship between characteristics (including sex, age at study entry, ethnicity, geographic region, age at diagnosis, duration of illness, number of prior hospitalizations, serum prolactin, and baseline Tanner stages) and onset or risk of PPRL-TEAEs. The secondary objective was to assess sexual maturation during long-term treatment with paliperidone ER.

Results

In total, 400 patients were enrolled in the study and 184 patients completed the 2-year study; the majority were boys (61%), White (66%), and aged >14 years at study enrolment (73%) with mean (standard deviation [SD]) body mass index (BMI) of 21.96 (4.375) kg/m² at baseline. Girls (18.5%) had a higher incidence of PPRL-TEAEs than did boys (3.3%). Most of these events were mild to moderate in severity, and none were serious; four patients discontinued the study due to PPRL-TEAEs. Mean prolactin levels in the total population of boys and girls increased early during treatment then stabilized with time. Mean ± SD maximum changes in prolactin levels from baseline were higher in girls and boys with PPRL-TEAEs than in those without (Girls: 74.7 ± 32.3 ng/ml [n = 28] vs. 50.5 ± 44.9 ng/ml [n = 114]; p = 0.008. Boys: 33.6 ± 23.7 ng/ml [n = 8] vs. 31.0 ± 24.5 ng/ml [n = 205]; p = 0.77). No clinically significant mean changes from baseline in growth-adjusted z-score for weight, height, or BMI were observed. Overall, ~90% of the patients who completed the 2-year study achieved Tanner stages 4–5 by study endpoint. Female sex, age at diagnosis (13–14 years), girls of Hispanic ethnicity, and region (EU and North America) were associated with a greater risk for PPRL-TEAEs; higher baseline Tanner stages for pubic hair (boys and girls) and breast development (stage 3 vs. 4 or 5) also seemed to be associated with a higher incidence of PPRL-TEAEs.

Conclusions

Female sex appeared to be associated with an increased risk for PPRL-TEAEs. Other potential predictors, such as ethnicity, region, age at diagnosis, and Tanner stage 4 or 5, all seemed to be related to sex. Evidence from this study was insufficient to definitively conclude that prolactin values at baseline and change during treatment were predictive of PPRL-TEAEs, although there is a signal that this may be the case in girls. These results are exploratory in nature, and confirmatory studies are needed to confirm these observations.

Trial Registration

ClinicalTrials.gov identifier: NCT00488319.

http://ift.tt/2uhJAGO

Polymer-based hydrogel scaffolds for skin tissue engineering applications: a mini-review

Abstract

Polymer hydrogels consist of a three-dimensional (3D) structure with cross-linked networks rich in a huge amount of water through hydrogen-bonding interactions, making them highly hydrophilic. Due to their impressive hydrophilic characteristics and cell non-cytotoxicity, polymer hydrogels are useful tissue engineering tools for the organization of cells and tissues and organ regeneration. Many biomedical engineers and researchers have recently begun to utilize polymer hydrogels as tissue or cell culture environments and as scaffolds for the stable growth of organs in tissue engineering and regeneration medicine. This paper focuses on skin regeneration in polymer hydrogels where skin is a means of protecting the body from infection or physical or chemical damage. Generally, skin tissue that has incurred minor damage or wounds can regenerate and heal in a relatively short time, while severe injuries may require transplantation or artificial skin. For those purposes, skin culturing in an in vitro environment is essential, and the environment produced using polymer hydrogel scaffolds needs to be both similar to the real environment and safe for skin cell growth. This paper reviews post-2000 skin regeneration research in the field of tissue engineering, focusing specifically on polymer hydrogels; it also discusses some of the central perspectives and key issues.

http://ift.tt/2s34fxr

The Identification and Tracking of Uterine Contractions Using Template Based Cross-Correlation

Abstract

The purpose of this paper is to outline a novel method of using template based cross-correlation to identify and track uterine contractions during labour. A purpose built six-channel Electromyography (EMG) device was used to collect data from consenting women during labour and birth. A range of templates were constructed for the purpose of identifying and tracking uterine activity when cross-correlated with the EMG signal. Peak finding techniques were applied on the cross-correlated result to simplify and automate the identification and tracking of contractions. The EMG data showed a unique pattern when a woman was contracting with key features of the contraction signal remaining consistent and identifiable across subjects. Contraction profiles across subjects were automatically identified using template based cross-correlation. Synthetic templates from a rectangular function with a duration of between 5 and 10 s performed best at identifying and tracking uterine activity across subjects. The successful application of this technique provides opportunity for both simple and accurate real-time analysis of contraction data while enabling investigations into the application of techniques such as machine learning which could enable automated learning from contraction data as part of real-time monitoring and post analysis.

http://ift.tt/2tq6csa

The effects of alpha-lipoic acid on diabetic myopathy

Abstract

Purpose

Increased oxidative stress and impaired antioxidant defense are important mechanisms in the pathogenesis of diabetic myopathy. Since diabetes mellitus type 1 decreases muscle regeneration capacity the present study was designed to determine the influence of alpha-lipoic acid (ALA), a potent biological antioxidant, on the process of regeneration of diabetic rat skeletal muscles.

Methods

40 Wistar rats were divided into three groups: control (n = 8), untreated diabetic group (n = 16) and ALA treated diabetic group (n = 16). The regeneration process was provoked in streptozotocin-induced diabetic rats in both slow (m.soleus, SOL) and fast (m.extensor digitorum longus, EDL) skeletal muscles by intramuscular injection of myotoxin bupivacaine. At intervals of 10 days and 4 weeks, muscle histochemical and morphometrical analysis (fiber cross areas and fiber type distribution) was performed.

Results

Changes induced by diabetes are evident in redistribution of muscle fibers and in significant level of atrophy. After 4 weeks of diabetes, glycolytic muscle fibers are dominant in both slow and fast muscles. Muscle atrophy is present in all fiber types except in type I of slow skeletal muscle. Treatment with ALA reduce changes in the morphological properties caused by diabetes mellitus type 1 in slow and fast rat skeletal muscles during the process of regeneration.

Conclusion

Treatment with lipoic acid during 4 weeks has shown effects on the redistribution of muscle fibers, and can prevent atrophy in slow and fast diabetic muscle.

http://ift.tt/2t1SMzC

PVP immobilized SiO 2 nanospheres for high-performance shear thickening fluid

Abstract

We develop a modified method to improve the rheological performance of SiO₂-based shear thickening fluid (STF). Directly adding surfactant into STF is the most common method to improve the rheological performance of SiO₂-based STF. However, the final viscosity increases quickly with the increase of shear rate, which is against for the practical applications. In this work, SiO₂ nanospheres are firstly modified by PVP K30 through an ethanol refluxing method and the modified SiO₂ nanospheres are used to prepare PVP@SiO₂-STF. Compared with the unmodified SiO₂ based STF (SiO₂-STF), the PVP@SiO₂-STF presents an obvious increase of shear thickening (ST) effects and the maximum viscosity increases by 7 times and the critical shear rates decrease about 10 times approximately. A reasonable explanation is proposed to interpret the influence of the modification methods on the rheological properties of STF. This work provides a new way to control the shear thickening behavior and also contributes to understand the mechanism of ST effect, which has an important significance to develop controllable STF.

Graphical abstract

Figure PVP immobilized SiO₂ based shear thickening fluid shows a dramatic improvement in shear thickening behavior (a, b, and c) and the illustration of the enhanced mechanism of shear thickening (d).

http://ift.tt/2tZoq11

Simulation model of the growth of sweet orange ( Citrus sinensis L. Osbeck) cv. Natal in response to climate change

Abstract

The objective of the present study was to develop a simulation model of the growth of sweet orange (Citrus sinensis L. Osbeck) cv. Natal in response to climate change based on system dynamics principles. The model was developed based on a system analysis of the factors that affect crop biomass formation. The main variables considered were atmospheric carbon dioxide (CO₂), air temperature, transpiration, rainfall, water deficit, irrigation depth, canopy volume, and the respective interrelationships. Simulations were performed for the period from 2010 to 2100. Overall, the model results indicate that the increase in atmospheric CO₂ concentrations predicted in the Intergovernmental Panel on Climate Change (IPCC) report, combined with air temperatures higher, lower, or equal to those generally occurring in natural environments, will result in higher water use efficiency by orange trees. When other factors, such as the soil water deficit, were included in the model, the water productivity was predicted to be lower in 2100 without irrigation than when irrigation was included. It is concluded that the model is suitable for determination of the effects of climate change on water use efficiency of sweet orange cv. Natal. Increased atmospheric CO₂ concentrations will result in higher CO₂ assimilation in orange trees and therefore in increased biomass production (g) per unit of water transpired (mm). However, this positive effect may be masked by other effects of atmospheric CO₂ increases, mainly those associated with temperature.

http://ift.tt/2tlqt1S

Towards a balanced view of Arctic shipping: estimating economic impacts of emissions from increased traffic on the Northern Sea Route

Abstract

The extensive melting of Arctic sea ice driven by climate change provides opportunities for commercial shipping due to shorter travel distances of up to 40% between Asia and Europe. It has been estimated that around 5% of the world's trade could be shipped through the Northern Sea Route (NSR) in the Arctic alone under year-round and unhampered navigability, generating additional income for many European and East Asian countries. Our analysis shows that for Arctic sea ice conditions under the RCP8.5 emissions scenario and business restrictions facing shipping companies, NSR traffic will increase steadily from the mid-2030s onwards, although it will take over a century to reach the full capacity expected for ice-free conditions. However, in order to achieve a balanced view of Arctic shipping, it is important to include its detrimental environmental impacts, most notably emissions of short-lived pollutants such as black carbon, as well as CO₂ and non-CO₂ emissions associated with the additional economic growth enabled by NSR. The total climate feedback of NSR could contribute 0.05% (0.04%) to global mean temperature rise by 2100 under RCP8.5 (RCP4.5), adding $2.15 trillion ($0.44 trillion) to the NPV of total impacts of climate change over the period until 2200 for the SSP2 socio-economic scenario. The climatic losses offset 33% (24.7%) of the total economic gains from NSR under RCP8.5 (RCP4.5), with the biggest losses set to occur in Africa and India. These findings call for policy instruments aimed at reducing emissions from Arctic shipping and providing compensation to the affected regions.

http://ift.tt/2s32Gjg

When do extreme weather events generate attention to climate change?

Abstract

We analyzed the effects of 10,748 weather events on attention to climate change between December 2011 and November 2014 in local areas across the USA. Attention was gauged by quantifying the relative increase in Twitter messages about climate change in the local area around the time of each event. Coastal floods, droughts, wildfires, strong wind, hail, excessive heat, extreme cold, and heavy snow events all had detectable effects. Attention was reliably higher directly after events began, compared to directly before. Financial damage associated with the weather events had a positive and significant effect on attention, although the effect was small. The abnormality of each weather event's occurrence compared to local historical activity was also a significant predictor. In particular and in line with past research, relative abnormalities in temperature (local warming) generated attention to climate change. In contrast, wind speed was predictive of attention to climate change in absolute levels. These results can be useful to predict short-term attention to climate change for strategic climate communications and to better forecast long-term climate policy support.

http://ift.tt/2s2vU1D

Developed barrier island adaptation strategies to hurricane forcing under rising sea levels

Abstract

Global sea levels have risen at a rate of 1.7 mm/year over the last century and are projected to rise an additional 0.2 to 2.0 m by 2100 with some regions experiencing higher rise in relative sea level due to localized processes. As sea levels rise, low-lying, narrow barrier islands are threatened by episodic flooding and wave impact and are particularly vulnerable during storm events. These types of islands are ubiquitous along the U.S. East and South coasts and other coasts worldwide. In this study, we evaluate the effectiveness of several adaptation strategies, including combinations of nature-based and hard structures, on developed barrier islands to hurricane forcing under future sea levels. Interpreting the results of a morphological numerical model, beach nourishment from the toe of the dune to the depth of closure (i.e., active beach only) provides only a slight increase in protection for the island from hurricane forcing as sea levels rise. Raising elevations of the existing dune or existing buried seawall effectively reduces overall volumetric erosion but, under extreme sea level rise, does not protect against bay-side flooding and severe back-barrier erosion. Raising the elevation of the entire island, particularly the back-barrier region, offered the greatest protection from severe erosion on the developed barrier island under future sea level states and hurricane forcing. Using these results, an adaptation pathway based on level of sea level rise is created to illustrate the effectiveness of an adaptive approach in managing the accelerating risk posed by sea level rise.

http://ift.tt/2tlNKRg

Contributions of decadal climate information in agriculture and food systems in east and southern Africa

Abstract

Whilst there has been much focus on the utility of climate information on the seasonal timescale and several decades into the future vis-à-vis decision-making and responses to climate and related risks in Africa, less attention has been given to information on the decadal timescale. Yet much policy, planning and investment decision-making within African agricultural and food systems take place within this timescale. Decadal prediction research itself has become a hot topic, and it is against this background that we explore the questions, 'what climate information could be utilised by farmers within this timescale and of what value will it be?' Using case studies of both small and large-scale farming systems in east and southern Africa, we show decadal climate information potentially providing opportunities for flexible, proactive and innovative decision-making in response to projected dynamics within this period, ultimately bridging the current gap not covered by seasonal forecasts and climate change projections.

http://ift.tt/2tluVgV

Does the label really matter? Evidence that the US public continues to doubt “global warming” more than “climate change”

Abstract

Does the public doubt the existence of "global warming" more than "climate change"? While previously published research suggests that it does, others have argued that this effect either never existed or has disappeared amid broader shifts in public opinion. We draw on survey response theory to help reconcile this debate. We then analyze data from an October 2016 probability-based survey experiment (n = 1461 US adults) to test the prediction that the US public (and particularly, Republicans) continue to respond differently when asked whether global warming vs. climate change exists. Indeed, respondents who were asked about climate change responded "Yes" (definitely or somewhat) more often (85.8%) than respondents who were asked about global warming (80.9%), an effect observed for Republicans (74.4 vs. 65.5%) but not Democrats (94% in both conditions). We discuss broader implications for US public opinion and discourse in an era of significant proposed government rollbacks of climate and environmental policy.

http://ift.tt/2s2HMAD

An intergenerationally fair path towards 2 °C

Abstract

In this paper, we argue that important questions of the intergenerational distribution of the costs of climate change remain even if a temperature target 2 °C is assumed because the target can be pursued in ways that assign costs differently across generations. Moreover, the discounted utilitarian approach that is standard in the economics literature is suspect in light of an a priori argument about its fairness. We also compare the results of modeling Nordhaus's version of discounted utilitarianism, constrained by a 2-degree warming parameter, with a similarly constrained version of a principle that requires minimizing the accumalted differences in the burdens of climate change costs across generations. The model comparison demonstrates that the a priori worry about discounted utilitarianism is largely born out. Nordhaus's version of discounted utilitarianism assigns poorer generations a heavier burden because it is optimific to do so. These arguments call into question the tremendous credibility that discounted utilitarianism enjoys in climate policy. The most important policy implication of the paper is that in order to pursue a fair path towards limiting warming to 2 °C, policy should be directed to increasing the price of carbon over the short term significantly more than what is called for by Nordhaus's model.

http://ift.tt/2s2YDDG

Variations of N 2 O fluxes in response to warming and cooling in an alpine meadow on the Tibetan Plateau

Abstract

Little is known about the impacts of climate change especially for cooling on N₂O emissions from alpine meadows on the Tibetan Plateau. Along a slope of Qilian mountains, China, we transferred intact soil cores covering different vegetation types (graminoid, shrub, forb, and sparse vegetation) downhill (warming) and uphill (cooling) across a 600-m elevation gradient to examine the responses of soil-atmosphere N₂O exchange rates to climate warming and cooling. N₂O fluxes were measured during two growing seasons from May to October in 2008 and 2009. The Tibetan alpine meadow acted as a net N₂O source at an average rate of 5.2 μg m⁻² h⁻¹ (ranging from 2.0 to 11.5 μg m⁻² h⁻¹). In situ N₂O emission generally decreased with elevation increase except for sparse vegetation, but significant differences were only found between graminoid and other three vegetations in 2008 and between graminoid and shrub vegetation in 2009. Warming averagely increased mean N₂O fluxes by 219% (ranging from 126 to 287%) while cooling decreased it by 75% (ranging from 57 to 95%) across four vegetation types over the variation of soil temperature from 1.3 to 5.5 °C. However, opposite effects were also observed in some cases due to modification of variations in soil moisture. Soil temperature and moisture had a positive effect on N₂O fluxes and explained 48 and 26% of the variation in mean N₂O fluxes across the four vegetation types, respectively. No relationship was found between mean N₂O fluxes and aboveground biomass. Our results suggest that more N₂O-N would be released from soil in a warmer future and that less N₂O emission during cool and dry years is expected in the Tibetan alpine meadow.

http://ift.tt/2s37c16

Promoting climate justice in high-income countries: lessons from African American communities on the Chesapeake Bay

Abstract

Climate change will unevenly affect people and societies throughout the world. Although high-income nations possess a wealth of adaptation resources, without proper planning, their most vulnerable populations will suffer severely and unjustly. We draw on methods from environmental anthropology and policy analysis to assess the potential to increase justice for African American communities that are particularly vulnerable to flooding from sea-level rise on the Chesapeake Bay. At a multistakeholder workshop, participants identified seven obstacles to increasing justice—lack of resources, preparedness, social capital, transparency, representation, information, and utilization of community knowledge. Participants also identified opportunities to address injustice, particularly by seeking greater engagement and mutual education. Analysis of workshop dialogue revealed that policymakers' and community members' differing perspectives on time, vulnerability, environmental conservation, and knowledge are key—but not insurmountable—obstacles to addressing injustice. We conclude with specific policy recommendations for moving Maryland toward a more just system of adaptation. Our recommendations emphasize that attending to procedural justice is essential to realize climate justice both in Maryland and around the world.

http://ift.tt/2tlEbSf

Impacts of climate change on European hydrology at 1.5, 2 and 3 degrees mean global warming above preindustrial level

Abstract

Impacts of climate change at 1.5, 2 and 3 °C mean global warming above preindustrial level are investigated and compared for runoff, discharge and snowpack in Europe. Ensembles of climate projections representing each of the warming levels were assembled to describe the hydro-meteorological climate at 1.5, 2 and 3 °C. These ensembles were then used to force an ensemble of five hydrological models and changes to hydrological indicators were calculated. It is seen that there are clear changes in local impacts on evapotranspiration, mean, low and high runoff and snow water equivalent between a 1.5, 2 and 3 °C degree warmer world. In a warmer world, the hydrological impacts of climate change are more intense and spatially more extensive. Robust increases in runoff affect the Scandinavian mountains at 1.5 °C, but at 3 °C extend over most of Norway, Sweden and northern Poland. At 3 °C, Norway is affected by robust changes in all indicators. Decreases in mean annual runoff are seen only in Portugal at 1.5 °C warming, but at 3 °C warming, decreases to runoff are seen around the entire Iberian coast, the Balkan Coast and parts of the French coast. In affected parts of Europe, there is a distinct increase in the changes to mean, low and high runoff at 2 °C compared to 1.5 °C, strengthening the case for mitigation to lower levels of global warming. Between 2 and 3 °C, the changes in low and high runoff levels continue to increase, but the changes to mean runoff are less clear. Changes to discharge in Europe's larger rivers are less distinct due to the lack of homogenous and robust changes across larger river catchments, with the exception of Scandinavia where discharges increase with warming level.

http://ift.tt/2s2ALA0

Stranded research? Leading finance journals are silent on climate change

Abstract

Finance research has shaped the modern financial system, influencing investors and market participants directly through research findings and indirectly through teaching and training programmes. Climate change presents major risks to the global financial system as well as new opportunities for investors. Is climate finance an important topic in finance research? We systematically analyse the content of 20,725 articles published in the leading 21 finance journals between January 1998 and June 2015. We find that only 12 articles (0.06%) are related in some way to climate finance. The three elite finance journals (Journal of Finance, Journal of Financial Economics and Review of Financial Studies) did not publish a single article related to climate finance over the 17.5-year period. We repeat our analysis across a sample of 29 elite business journals spanning accounting, economics, management, marketing and operations research, as well as finance. We find a similar dearth of published climate finance research. We consider four possible explanations for this failure of top finance and business journals to engage with climate finance as a research topic. These include methodological constraints and editorial policies. We conclude by arguing why it is critical for climate-related research to be given greater attention and prominence in finance journals.

http://ift.tt/2tlIKMh

Climate change threats to one of the world’s largest cross-country skiing races

Abstract

This study investigates the relationship between climate variability and the participant cancellation ratio at one of the world's oldest, longest and largest cross-country skiing races, the Vasaloppet. This race is held in the Swedish region of Dalarna on the first Sunday of March each year. Data are based on the number of registered and starting skiers and local weather conditions (natural snow supply and temperature) for the period 1951–2016. As the dependent variable is bounded between zero and one, the fractional logit model is employed. Estimations show that a lack of natural snow significantly increases the cancellation ratio. In particular, a decline in snow depth from the average level of 57 to 30 cm over the sample period leads to an increase of 3.3 percentage points in the cancellation ratio. Interestingly, the dependence on natural snow has declined in absolute terms in recent years due to various adaptation practices, such as snow storage and snow production.

http://ift.tt/2s2SEOY

Dynamical anomalies in terrestrial proxies of North Atlantic climate variability during the last 2 ka

Abstract

Recent work has provided ample evidence that nonlinear methods of time series analysis potentially allow for detecting periods of anomalous dynamics in paleoclimate proxy records that are otherwise hidden to classical statistical analysis. Following upon these ideas, in this study, we systematically test a set of Late Holocene terrestrial paleoclimate records from Northern Europe for indications of intermittent periods of time- irreversibility during which the data are incompatible with a stationary linear-stochastic process. Our analysis reveals that the onsets of both the Medieval Climate Anomaly and the Little Ice Age, the end of the Roman Warm Period, and the Late Antique Little Ice Age have been characterized by such dynamical anomalies. These findings may indicate qualitative changes in the dominant regime of interannual climate variability in terms of large-scale atmospheric circulation patterns, ocean-atmosphere interactions, and external forcings affecting the climate of the North Atlantic region.

http://ift.tt/2tlDzvS

A novel proxy and the sea level rise in Venice, Italy, from 1350 to 2014

Abstract

The evolution of relative sea level (RSL) in Venice, Italy, is crucial for the safeguarding of the city and it is now possible to extend our knowledge back to 1350, including the whole Little Ice Age and modern global warming. The existing tide gauge record is extensive, going back to 1871, but it is affected by the superposition of multidecadal swings and short-term fluctuations, including both natural and manmade forcing factors. A biological proxy, i.e. the green algae belt reported on paintings made with the help of a camera obscura by the Venetian painters Canaletto and Bellotto (eighteenth century) and Veronese (sixteenth century), helps us to go back to 1571. This paper presents an exceptionally long series (i.e. 664 years) and adds a novel proxy: the submersion of water stairs of the historic palaces facing the Grand Canal. Originally, the bottom step of the water stairs was built in relation to the sea level and the slippery algae belt, while today, the water stairs are mostly submerged. An underwater survey of 78 water stairs has provided new data about the RSL since 1350. The results show that RSL in Venice was always rising at an increasingly fast rate. By subtracting local land subsidence (LLS) from RSL, absolute (eustatic) sea level (ASL) has been calculated. For both RSL and ASL, the apparent acceleration is +0.0030 ± 0.0004 mm year⁻². This figure becomes unstable when the record length is reduced. A discussion is made about the interpolation functions, i.e. the second-order polynomial and the exponential that provide almost the same best-fit over the common period. The RSL and ASL trend lines and the possibility of turning points are also discussed and compared with other scholarly studies. A eustatic turning point is suggested for the mid fifteenth century, consistent with the literature. However, the comparison between scholarly papers is difficult due to geographic and geological differences between sites and record durations.

http://ift.tt/2tlRh1F

Bioinspired magnetic reception and multimodal sensing

Abstract

Several animals use Earth's magnetic field in concert with other sensor modes to accomplish navigational tasks ranging from local homing to continental scale migration. However, despite extensive research, animal magnetic reception remains poorly understood. Similarly, the Earth's magnetic field offers a signal that engineered systems can leverage to navigate in environments where man-made positioning systems such as GPS are either unavailable or unreliable. This work uses a behavioral strategy inspired by the migratory behavior of sea turtles to locate a magnetic goal and respond to wind when it is present. Sensing is performed using a number of distributed sensors. Based on existing theoretical biology considerations, data processing is performed using combinations of circles and ellipses to exploit the distributed sensing paradigm. Agent-based simulation results indicate that this approach is capable of using two separate magnetic properties to locate a goal from a variety of initial conditions in both noiseless and noisy sensory environments. The system's ability to locate the goal appears robust to noise at the cost of overall path length.

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Announcements August 2017

http://ift.tt/2sS1oKR

Reply to the Letter to the Editor on “Helicobacter Pylori Does Not Affect Postoperative Outcomes after Sleeve Gastrectomy”

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Cervical laminectomy of limited width prevents postoperative C5 palsy: a multivariate analysis of 263 muscle-preserving posterior decompression cases

Abstract

Purpose

Between 2006 and 2010, we performed wide laminectomy (wide LAM) alone, with decompression performed between the bilateral medial margin of the zygapophyseal joints, or double-door laminoplasty (DL) combined with wide LAM for cervical compressive myelopathy (CCM). From 2010, instead of wide LAM and DL, we began to perform narrow LAM, where the laminectomy width was no more than 2–3 mm wider than the spinal cord width (SW). This study aimed to elucidate the risk factors for C5 palsy by reviewing surgical outcomes.

Methods

The clinical features and radiological findings of 263 CCM patients with or without C5 palsy were compared. Risk factors for C5 palsy were assessed using logistic regression analysis. The decompression width (DW) was defined as the laminectomy width or the width between the bilateral medial margins of the bony gutters in DL.

Results

Narrow LAM reduced the incidence of C5 palsy from 9.2 to 1.2%. DL was performed more frequently in the C5 palsy group. The difference between the DW and the SW (DW − SW) was significantly greater in the C5 palsy group. Posterior spinal cord shift, aging, and the number of consecutive laminae surgically treated were significantly higher in the C5 palsy group. The diameter of the foramen (DF) at C4/5 was significantly smaller in the C5 palsy patients. The logistic regression analysis revealed that DL, DW − SW, DF, and aging were risk factors for C5 palsy.

Conclusions

Cervical laminectomy of limited width prevented postoperative C5 palsy without compromising the functional recovery.

http://ift.tt/2si4Wal

Evaluating non-responders of a survey in the Swedish fracture register: no indication of different functional result

Abstract

Background

The Swedish Fracture Register (SFR) currently contains information on more than 190,000 fractures. Patient Reported Outcome Measures (PROMs) are used for monitoring functional results after fracture treatment. One weakness, as in many surveys, is a low response rate. The aim of the current study was to examine if non-responders of a survey in the SFR differ in PROMs scores, how age and gender influence the response rate and reasons for not responding.

Methods

Patients with fractures of radius, ulna or humerus between June and August 2013 and registered in the SFR were included in the study. The non-responders to both the pre-injury and the 1-year survey were contacted by phone and reminded to reply. A comparison of the results of both EQ-5D and Short Musculoskeletal Function Assessment (SMFA) could be made between the responders after a phone reminder and the initial responders. The response rate for the register as a whole was extracted in order to identify how age and gender affect the response rate.

Results

Three hundred seventeen of the patients included in the study responded initially. After phone reminder another 94 patients answered the pre-injury survey. Two hundred sixty eight responded initially to the 1-year follow-up survey and 42 after phone reminder. No significant difference was identified in the score of the pre-injury survey between initial responders and responders after phone reminder neither in the EQ-5D nor in the Short Musculoskeletal Function Assessment (SMFA). Regarding the 1-year survey, responders after a phone reminder reported a significantly better outcome in crude data of SMFA score. This difference disappeared after controlling for confounding factors through case control matching. The highest response rate to PROMs in the SFR was among females in the age range 60–69 years.

Conclusion

This study indicates that both in the preinjury survey as well as in the 1-year survey the non-responders in the SFR report similar function compared to the initial responders. Age and gender of patients affect the response rate of the survey which needs to be taken into consideration in analysis of data from the SFR.

http://ift.tt/2s2vSqr

Comparison of Complications Following Laparoscopic and Endoscopic Gastrostomy Placements

Abstract

Introduction

Percutaneous endoscopic gastrostomy (PEG) and laparoscopic gastrostomy (LG) placements provide enteral access to patients unable to tolerate oral feeds. Limited data comparing PEG and LG outcomes is available in adults. This study compares complications between PEG and LG placements.

Materials and Methods

A retrospective chart review was completed for patients undergoing PEG or LG placement at a single academic center between 2007 and 2014. Patient demographics, comorbidities, and Charlson Comorbidity Index (CCI) were compared. Logistic regression was utilized to identify independent predictors for complication.

Results

Two hundred and twenty-four patients (164 PEGs and 60 LGs) were evaluated. Patients undergoing LG had a higher incidence of prior surgery (42 vs 20%; P < 0.01) and age-adjusted CCI (5 vs 4; P = 0.01). Return to the OR was more common following PEG than LG (5.5 vs 0%) but did not achieve significance (P = 0.12). There were no differences in 30-day mortality; however, age-adjusted CCI was predictive of 30-day mortality (OR 1.3, 95% CI 1.1–1.6).

Conclusion

Despite increased comorbidities, LG tubes are at least as safe as PEGs. Research should focus on identifying predictive factors associated with post-operative complications to identify which patients would have superior outcomes with LG placement.

http://ift.tt/2uiO2VQ

Rupture of Cystic Artery Pseudoaneurysm: a Rare Complication of Acute Cholecystitis

Abstract

Pseudoaneurysm (PA) of the cystic artery is rare. Most of the reported cases are iatrogenic and develop secondary to liver biopsy, laparoscopic cholecystectomy, ERCP, and liver transplant. Other reported causes include trauma, malignancy, arteriovenous malformations, and inflammation in the hepatobiliary and pancreatic system. Cystic artery psuedoaneurysm is usually asymptomatic but may also present as vague abdominal pain, intra-abdominal mass, and hemobilia. In the event of rupture, it may present as a catastrophic intra-peritoneal bleeding with hemorrhagic shock. Doppler ultrasound and contrast-enhanced CT scan are useful tools for the diagnosis of this condition. However, selective visceral angiography is confirmatory and offers the opportunity for therapeutic embolization. We report a case which presented with upper right quadrant abdominal pain, vomiting, and hypotension. Abdominal ultrasonography revealed subhepatic hematoma and pericholecystic fluid collection along with acute calculus cholecystitis and sludge in the bile duct. Subsequent contrast-enhanced CT and CT angiography confirmed the presence of ruptured cystic artery psuedoaneurysm with subhepatic hematoma. The patient after resuscitation underwent selective visceral angiography and successful coil embolization of the cystic artery pseudoaneurysm. During the same admission, ERCP and biliary stenting were also performed followed by laparoscopic cholecystectomy. This case reports a rare entity which was successfully treated using a multimodality strategy.

http://ift.tt/2sn03Ik

Advanced glycation endproducts induce self- and cross-tolerance in monocytes

Abstract

Introduction

Advanced glycation endproducts (AGEs) are well-known inflammatory mediators, which are recognized by immune cells through their corresponding receptor RAGE and have been shown to participate in the pathophysiology of a variety of acute as well as chronic inflammatory diseases. Nevertheless, no data are available on the aftermath of AGE recognition on immune cells.

Materials and methods

We used the monocytic cell line MonoMac6 as well as primary human monocytes for double stimulation experiments. We measured secreted as well as intracellular levels of TNF-α using ELISA and flow cytometry. In addition, gene expression of surface receptors (RAGE and TLR4) and TNF were measured by qPCR.

Results

Stimulation with AGE leads to a dose-dependent induction of self- and cross-tolerance in both primary monocytes as well as the MonoMac6 cell line. The AGE tolerance depended neither on a decreased expression of RAGE or TLR4, nor on a decrease of TNF-α expression. Nevertheless, intracellular TNF-α was decreased, hinting towards a posttranscriptional regulation.

Conclusion

High levels of AGEs are capable to activate immune cells at first, but induce a secondary state of hypo-responsiveness in these cells. Based on the origin of its causal agent, we propose this phenomenon to be "metabolic tolerance".

http://ift.tt/2tpBLSV

Challenges to the Provision of Sexual and Reproductive Health Care to Refugee and Migrant Women: A Q Methodological Study of Health Professional Perspectives

Abstract

This Q methodological study was conducted to examine the perspectives of health professionals in providing sexual and reproductive health (SRH) care to refugee and migrant women. Forty-seven health professionals rank-ordered 42 statements and commented on their rankings in subsequent open-ended questions. A bi-person factor analysis was performed and factors were extracted according to the centroid method with a varimax rotation. Seven factors each with a distinct and meaningful viewpoint were identified. These factors are: "Communication difficulties—hurdles to counselling", "Lack of access to culturally appropriate care", "Navigating SRH care", "Cultural constraints on effective communication", "Effects of the lack of cultural competency", "Impacts of low income and language barrier" and "SRH services are accessible, but not culturally relevant". A more culturally adaptive healthcare model that considers refugee and migrant women's linguistic, cultural and socio-economic backgrounds; and engages health professionals on an ongoing process of building cultural competency is central to improve SRH access to these women.

http://ift.tt/2tlgQzI

A smartphone application to determine body length for body weight estimation in children: a prospective clinical trial

Abstract

The aim of this study was to test the feasibility and accuracy of a smartphone application to measure the body length of children using the integrated camera and to evaluate the subsequent weight estimates. A prospective clinical trial of children aged 0–<13 years admitted to the emergency department of the University Children's Hospital Zurich. The primary outcome was to validate the length measurement by the smartphone application «Optisizer». The secondary outcome was to correlate the virtually calculated ordinal categories based on the length measured by the app to the categories based on the real length. The third and independent outcome was the comparison of the different weight estimations by physicians, nurses, parents and the app. For all 627 children, the Bland Altman analysis showed a bias of −0.1% (95% CI −0.3–0.2%) comparing real length and length measured by the app. Ordinal categories of real length were in excellent agreement with categories virtually calculated based upon app length (kappa = 0.83, 95% CI 0.79–0.86). Children's real weight was underestimated by physicians (−3.3, 95% CI −4.4 to −2.2%, p < 0.001), nurses (−2.6, 95% CI −3.8 to −1.5%, p < 0.001) and parents (−1.3, 95% CI −1.9 to −0.6%, p < 0.001) but overestimated by categories based upon app length (1.6, 95% CI 0.3–2.8%, p = 0.02) and categories based upon real length (2.3, 95% CI 1.1–3.5%, p < 0.001). Absolute weight differences were lowest, if estimated by the parents (5.4, 95% CI 4.9–5.9%, p < 0.001). This study showed the accuracy of length measurement of children by a smartphone application: body length determined by the smartphone application is in good agreement with the real patient length. Ordinal length categories derived from app-measured length are in excellent agreement with the ordinal length categories based upon the real patient length. The body weight estimations based upon length corresponded to known data and limitations. Precision of body weight estimations by paediatric physicians and nurses were comparable and not different to length based estimations. In this non-emergency setting, parental weight estimation was significantly better than all other means of estimation (paediatric physicians and nurses, length based estimations) in terms of precision and absolute difference.

http://ift.tt/2tkMAWd

Drug-induced obesity and its metabolic consequences: a review with a focus on mechanisms and possible therapeutic options

Abstract

Weight gain is a common side effect of many widely used drugs. Weight gain of a few kilograms to an increase of 10% or more of initial body weight has been described. Not only the weight gain as such puts a burden on the health risks of the involved patients, the accompanying increase in the incidence of the metabolic syndrome, type 2 diabetes mellitus, and cardiovascular risk factors urges the caregiver to identify and to closely monitor the patients at risk. In this review, the different classes of drugs with significant weight gaining properties and the metabolic consequences are described. Specific attention is given to pathogenetic mechanisms underlying the metabolic effects and to potential therapeutic measures to prevent them.

http://ift.tt/2tplqO5

Hydrothermal synthesis of Cu-Fe 3 O 4 nanocomposites towards catalytic degradation of organic dyes

Abstract

Degradation of hazardous organic dyes utilizing multifunctional catalytic materials is supposed to be an efficient and promising method. Here, homogeneous Cu-Fe₃O₄ nanocomposites are synthesized through a facile and versatile one-pot hydrothermal method. The prepared Cu-Fe₃O₄ possesses spherical structure with rough surface and average diameter of 230 nm. High catalytic activity and structure stability make Cu-Fe₃O₄ nanocomposites effectively degrade rhodamine B, methylene blue, methyl orange, and congo red. The existence of magnetic Fe₃O₄ leads the nanocomposites to separate from the solution through external magnet and reuse for cycle degradation. And during the cyclic utilization, Cu-Fe₃O₄ nanocomposites keep high catalytic activity and, thus, could be used as an efficient degradation catalyst for the application of organic dyes.

Graphical abstract

http://ift.tt/2tpBq2O

Novel Nano Boehmite prepared by Solvothermal reaction of aluminum hydroxide gel in Monoethanolamine

Abstract

Solvothermal reaction of aluminum hydroxide gel (AHG) in monoethanolamine (MEA) was studied at several temperatures (100, 120, 150, and 200 °C) in several reaction times (2, 3, 4, 5, 6, and 13 h). The reaction product prepared at a low temperature of 120 °C in the reaction time more than 6 h gave a blue photoluminescence nanoboehmite intercalated with monoethanolamine derivatives (BM-MEA) in the colloidal solution, which showed a photoluminescence emission centered at 420 nm with an excitation of 360 nm. The powdery samples recovered from the reaction products were characterized by using elemental analysis, XRD analysis, IR spectroscopy, thermogravimetric (TG)-DTA, ¹³C and ²⁷Al CP/MAS NMR spectroscopies, N₂ gas adsorption/desorption isotherm, SEM and TEM images, and photoluminescence spectroscopy. The X-ray diffraction revealed that the basal space in BM-MEA was expanded from 0.61 to 1.2 nm by intercalation of MEA derivatives to boehmite, and the IR and ¹³C CP/MAS NMR spectra determined that the intercalated MEA derivatives are protonated- and carbamate-substituted MEAs, which are formed in the layers through a covalent bond with Al–OH groups on boehmite surface. The empirical formula of BM-MEA was estimated to be AlO(OH)_0.82(OCH₂CH₂NH₃⁺)_0.05(OCH₂CH₂NHCOO⁻)_0.13 on the basis of the elemental TG-DTA and IR spectral analyses. We discuss the reaction mechanism of a unique blue photoluminescence BM-MEA formed by proceeding in CO₂–H₂O–alkanolamine system.

Graphical abstract

Possible structure model of BM-MEA.

http://ift.tt/2tpEkEM

Multiparametric imaging for detection and characterization of hepatocellular carcinoma using gadoxetic acid-enhanced MRI and perfusion-CT: which parameters work best?

Abstract

Background

MRI and perfusion-CT (PCT) are both useful imaging techniques for detection and characterization of liver lesions. The aim of this study was to compare the diagnostic accuracy of imaging parameters derived from PCT and gadoxetic acid-enhanced MRI in patients with hepatocellular carcinoma (HCC).

Methods

36 patients with liver cirrhosis and a total of 67 lesions referred to our hospital for multi-parametric diagnosis of HCC-suspected liver lesions in the setting of liver cirrhosis were prospectively enrolled and underwent PCT and MRI. HCC diagnosis was confirmed either by histology (n = 60) or interval growth (n = 7). For PCT, mean/max blood flow (BF), blood volume (BV), k-trans, arterial liver perfusion (ALP), portal venous perfusion (PVP) and hepatic perfusion index (HPI) were quantified. Two readers identified the lesions based on single maps each being blinded to the number of lesions.

MRI-protocol included fat-suppressed T1w-VIBE sequences obtained before, 2, 5, 10 and 20 min after the injection of gadoxetic acid as well as non-enhanced coronal HASTE, axial T1w-VIBE, fat-suppressed T2w-TSE and DWI. Quantitative analysis was performed using enhancement ratios between tumor and liver parenchyma for post-contrast in the hepatobiliary phase (RIR_HB), arterial (ER_a) and late-venous (ER_v) phases as well as signal intensity ratios (liver/parenchyma) on T1w (RIR_T1) and T2w (RIR_T2).

Results

In PCT analysis, all lesions exhibited high BF_max values (63–250 mL/100 g tissue) and were visible on HPI maps with high degrees of arterial blood supply of (HPI > 96%).

In MRI, RIR_HB was negative in 8/67. 12/67 HCCs were missed on DWI. 46/67 HCCs showed wash-in and 47/67 HCC showed wash-out of contrast agent. 6/67 HCCs were missed on T1w and 11/67 were missed on T2w-sequences when analyzed separately, while analysis of multiparametric MRI combining typical enhancement pattern, visibility on hepatobiliary phase and T1w-images the same number of lesions as PCT irrespective of their size (1–19 cm) were detected. Quantification of early enhancement by ER_a or ER_v did not improve detection rates.

Conclusions

Perfusion-CT and gadoxetic acid-enhanced MRI were comparable in detecting HCC lesions. For PCT a mean HPI > 96% proved to be a very robust parameter for detection and characterization of HCC.

http://ift.tt/2t1fEiS

Paroxysmal freezing of gait in a patient with mesial frontal transient ischemic attacks

Abstract

Background

Rare patients have been reported who developed a mixture of gait disturbances following a focal lesion in the frontal lobe. Thus, the exact location of frontal lesion responsible for a specific gait disturbance is not well defined.

Case presentation

We describe a 47-year-old man who experienced two episodes of paroxysmal freezing of gait of the right leg. During the attacks, he had no motor weakness, sensory change, or disequilibrium. He had past history of panic attacks. Recently, he had been under severe emotional stress. T2 and diffusion brain magnetic resonance imaging scans were normal. So far, the most likely clinical diagnosis might be functional freezing of gait. However, magnetic resonance angiography showed atherosclerosis in the proximal left anterior cerebral artery. Perfusion scans showed a delayed mean transit time in the left mesial frontal lobe. He developed two more attacks during the four months of follow up.

Conclusions

The presented case illustrates that the mesial frontal lobe may be important in the pathophysiology of freezing of gait. We speculate that the supplementary motor area may generate a neuronal command for the initiation of locomotion that in our case may have been inhibited by a transient ischemia.

http://ift.tt/2s2eylB

Prediction of future malaria hotspots under climate change in sub-Saharan Africa

Abstract

Malaria is a climate sensitive disease that is causing rampant deaths in sub-Saharan Africa (SSA) and its impact is expected to worsen under climate change. Thus, pre-emptive policies for future malaria control require projections based on integrated models that can accommodate complex interactions of both climatic and non-climatic factors that define malaria landscape. In this paper, we combined Geographical Information System (GIS) and Bayesian belief networks (BBN) to generate GIS-BBN models that predicted malaria hotspots in 2030, 2050 and 2100 under representative concentration pathways (RCPs) 4.5 and 8.5. We used malaria data of children of SSA, gridded environmental and social-economic data together with projected climate data from the 21 Coupled Model Inter-comparison Project Phase 5 models to compile the GIS-BBN models. Our model on which projections were made has an accuracy of 80.65% to predict the high, medium, low and no malaria prevalence categories correctly. The non-spatial BBN model projection shows a moderate variation in malaria reduction for the high prevalence category among RCPs. Under the low prevalence category, an increase in malaria is seen but with little variation ranging between 4.6 and 5.6 percentage points. Spatially, under RCP 4.5, most parts of SSA will have medium malaria prevalence in 2030, while under RCP 8.5, most parts will have no malaria except in the highlands. Our BBN-GIS models show an overall shift of malaria hotspots from West Africa to the eastern and southern parts of Africa especially under RCP 8.5. RCP 8.5 will not expand the high and medium malaria prevalence categories in all the projection years. The generated probabilistic maps highlight future malaria hotspots under climate change on which pre-emptive policies can be based.

http://ift.tt/2smpXMz

Surfactant-assisted production of TbCu 2 nanoparticles

Abstract

The production of surfactant-assisted metallic nanoparticles of TbCu₂ has been achieved by the combination of high-energy ball milling in tungsten carbide containers and the use of oleic acid (C₁₈H₃₄O₂) and heptane (C₇H₁₆). The alloys were first produced in bulk pellets by arc melting and subsequently milled for only 2 and 5 h in oleic acid (15 and 30% mass weight). The powders consist of an ensemble of nanoparticles with a TbCu₂ lattice cell volume of ≈215 Å³, an average particle diameter between 9 and 12 nm and inhomogeneous lattice strain of 0.2–0.4%, as deduced from X-ray diffraction data. The nanometric sizes of the crystals with defined lattice planes are close to those obtained by transmission electron microscopy. Raman spectroscopy shows the existence of inelastic peaks between 1000 and 1650 cm⁻¹, a characteristic of C₁₈H₃₄O₂. The magnetisation shows a peak at the antiferromagnetic-paramagnetic transition with Néel temperatures around 48 K (below that of bulk alloy) and a distinctive metamagnetic transition at 5 K up to 40 K. The Curie-Weiss behaviour above the transition reveals effective Bohr magneton numbers (≈9.1–9.9 μ_B) which are close to what is expected for the free Tb³⁺ ion using Hund's rules. The metamagnetic transition is slightly augmented with respect to the bulk value, reaching H = 24.5 kOe by the combined effect of the size reduction and the lattice strain increase and the increase of magnetic disorder. At low temperatures, there is irreversibility as a result of the existing magnetic disorder. The moment relaxation follows an Arrhenius model with uncompensated Tb moments, with activation energies between 295 and 326 K and pre-exponential factors between 10⁻¹¹ and 10⁻¹³ s. The results are interpreted as a consequence of the existence of a diamagnetic surfactant which drastically decreases the magnetic coupling between interparticle moments.

http://ift.tt/2slRA8q

The Impact of Coverage Restrictions on Antipsychotic Utilization Among Low-Income Medicare Part D Enrollees

Abstract

Prior research demonstrates substantial access problems associated with utilization management and formulary exclusions for antipsychotics in Medicaid, but the use and impact of coverage restrictions for these medications in Medicare Part D remains unknown. We assess the effect of coverage restrictions on antipsychotic utilization in Part D by exploiting a unique natural experiment in which low-income beneficiaries are randomly assigned to prescription drug plans with varying levels of formulary generosity. Despite considerable variation in use of coverage restrictions across Part D plans, we find no evidence that these restrictions significantly deter utilization or reduce access to antipsychotics for low-income beneficiaries.

http://ift.tt/2uiDSoe

The novel compound PBT434 prevents iron mediated neurodegeneration and alpha-synuclein toxicity in multiple models of Parkinson’s disease

Abstract

Elevated iron in the SNpc may play a key role in Parkinson's disease (PD) neurodegeneration since drug candidates with high iron affinity rescue PD animal models, and one candidate, deferirpone, has shown efficacy recently in a phase two clinical trial. However, strong iron chelators may perturb essential iron metabolism, and it is not yet known whether the damage associated with iron is mediated by a tightly bound (eg ferritin) or lower-affinity, labile, iron pool. Here we report the preclinical characterization of PBT434, a novel quinazolinone compound bearing a moderate affinity metal-binding motif, which is in development for Parkinsonian conditions. In vitro, PBT434 was far less potent than deferiprone or deferoxamine at lowering cellular iron levels, yet was found to inhibit iron-mediated redox activity and iron-mediated aggregation of α-synuclein, a protein that aggregates in the neuropathology. In vivo, PBT434 did not deplete tissue iron stores in normal rodents, yet prevented loss of substantia nigra pars compacta neurons (SNpc), lowered nigral α-synuclein accumulation, and rescued motor performance in mice exposed to the Parkinsonian toxins 6-OHDA and MPTP, and in a transgenic animal model (hA53T α-synuclein) of PD. These improvements were associated with reduced markers of oxidative damage, and increased levels of ferroportin (an iron exporter) and DJ-1. We conclude that compounds designed to target a pool of pathological iron that is not held in high-affinity complexes in the tissue can maintain the survival of SNpc neurons and could be disease-modifying in PD.

http://ift.tt/2toXryu