bluuebunny/crossref_metadata_2025_split huggingface dataset:
In vitro to in vivo extrapolation of biotransformation rates for assessing bioaccumulation of hydrophobic organic chemicals in mammals
Authors: Lee Yung-Shan , Lo Justin C. , Otton S.Victoria , Moore Margo M. , Kennedy Chris J. , Gobas Frank A.P.C. 
Published: December 2016

Abstract

Incorporating biotransformation in bioaccumulation assessments of hydrophobic chemicals in both aquatic and terrestrial organisms in a simple, rapid, and cost-effective manner is urgently needed to improve bioaccumulation assessments of potentially bioaccumulative substances. One approach to estimate whole-animal biotransformation rate constants is to combine in vitro measurements of hepatic biotransformation kinetics with in vitro to in vivo extrapolation (IVIVE) and bioaccumulation modeling. An established IVIVE modeling approach exists for pharmaceuticals (referred to in the present study as IVIVE-Ph) and has recently been adapted for chemical bioaccumulation assessments in fish. The present study proposes and tests an alternative IVIVE-B technique to support bioaccumulation assessment of hydrophobic chemicals with a log octanol–water partition coefficient (KOW) ≥ 4 in mammals. The IVIVE-B approach requires fewer physiological and physiochemical parameters than the IVIVE-Ph approach and does not involve interconversions between clearance and rate constants in the extrapolation. Using in vitro depletion rates, the results show that the IVIVE-B and IVIVE-Ph models yield similar estimates of rat whole-organism biotransformation rate constants for hypothetical chemicals with log KOW ≥ 4. The IVIVE-B approach generated in vivo biotransformation rate constants and biomagnification factors (BMFs) for benzo[a]pyrene that are within the range of empirical observations. The proposed IVIVE-B technique may be a useful tool for assessing BMFs of hydrophobic organic chemicals in mammals. Environ Toxicol Chem 2017;36:1934–1946. © 2016 SETAC
Bacteriostatic behavior of surface modulated silicon nitride in comparison to polyetheretherketone and titanium
Authors: Bock Ryan M. , Jones Erin N. , Ray Darin A. , Sonny Bal B. , Pezzotti Giuseppe , McEntire Bryan J. 
Published: December 2016

AbstractPerioperative and latent infections are leading causes of revision surgery for orthopaedic devices resulting in significant increased patient care, comorbidities, and attendant costs. Identifying biomaterial surfaces that inherently resist biofilm adhesion and bacterial expression is an important emerging strategy in addressing implant‐related infections. This in vitro study was designed to compare biofilm formation on three biomaterials commonly employed in spinal fusion surgery—silicon nitride (Si3N4), polyetheretherketone (PEEK), and a titanium alloy (Ti6Al4V‐ELI) —using one gram‐positive and one gram‐negative bacterial species. Disc samples from various surface treated Si3N4, PEEK, and Ti6Al4V were inoculated with 105 CFU/mm2 Staphylococcus epidermidis (ATCC®14990™) or Escherichia coli (ATCC®25922™) and cultured in PBS, 7% glucose, and 10% human plasma for 24 and 48 h, followed by retrieval and rinsing. Vortexed solutions were diluted, plated, and incubated at 37 °C for 24 to 48 h. Colony forming units (CFU/mm2) were determined using applicable dilution factors and surface areas. A two‐tailed, heteroscedastic Student's t‐test (95% confidence) was used to determine statistical significance. The various Si3N4 samples showed the most favorable bacterial resistance for both bacilli tested. The mechanisms for the bacteriostatic behavior of Si3N4 are likely due to multivariate surface effects including submicron‐topography, negative charging, and chemical interactions which form peroxynitrite (an oxidative agent). Si3N4 is a new biomaterial with the apparent potential to inhibit biofilm formation. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 1521–1534, 2017.
Synthesis of a Fe/AC Fenton‐like catalyst and heterogeneous catalysis in decolorization of Sunset Yellow by pulsed high‐voltage discharge
Authors: Zhu Xinyan , Ma Yuepeng , Liu Ying , Yang Zemeng , Li Qunsheng , Zhou Zhiyong , Ren Zhongqi 
Published: December 2016

AbstractBACKGROUNDA new Fe/AC heterogeneous Fenton‐like catalyst was prepared using a dipping–sintering method. The prepared catalyst was characterized by X‐ray diffraction and scanning electron microscopy. The decolorization of Sunset Yellow was conducted in a self‐designed pulsed high‐voltage discharge system by the catalysis of the prepared heterogeneous catalyst. Effects of preparation conditions of catalyst (carrier material, sintering temperature and dipping time) and operating conditions (catalyst dosage, pH and treatment method) on decolorization efficiency were investigated.RESULTSSpherical activated carbon (AC) was selected as the carrier material and the optimal dipping time and sintering temperature were 8 h and 350 °C, respectively. The efficiency of decolorization of Sunset Yellow was above 90% after 30 min of a pulsed high‐voltage discharge process with 5 g heterogeneous catalyst and at pH 2.00. The utilization of copper mesh not only enhanced the decolorization of Sunset Yellow but also facilitated the reusability of the prepared heterogeneous catalyst. The efficiency of decolorization of Sunset Yellow with prepared Fe/AC heterogeneous Fenton‐like catalyst (5 g) was even a little higher than that with homogeneous catalyst (1.635 mmol L−1 Fe2+). The decolorization efficiency remained above 90% after ten recycles of the catalyst, indicating that the prepared heterogeneous catalyst has good stability and reusability. In addition, a possible catalytic mechanism for the decolorization reaction in a pulsed high‐voltage discharge system with prepared Fe/AC heterogeneous Fenton‐like catalyst was proposed by determination of H2O2 and ·OH concentrations in deionized water.CONCLUSIONSThe prepared Fe/AC heterogeneous Fenton‐like catalyst efficiently degrades Sunset Yellow wastewater in a pulsed high‐voltage discharge system. © 2016 Society of Chemical Industry
Microbial lipid production from lignocellulosic hydrolyzates: effect of carbohydrate mixtures and acid‐hydrolysis byproducts on cell growth and lipid production by Lipomyces starkeyi
Authors: Rahman Sharif , Arbter Philipp , Popovic Milan , Bajpai Rakesh , Subramaniam Ramalingam 
Published: December 2016

AbstractBACKGROUNDThe effects of byproducts of lignocellulosic hydrolyzates, such as furfural, 5‐hydroxy methyl furfural (HMF), vanillin, para‐hydroxy benzaldehyde (PHB), and syringaldehyde, on the growth and lipid accumulation by Lipomyces starkeyi were investigated. All the studies were conducted using a minimal medium.RESULTSThe growth and lipid accumulation patterns on individual sugars (glucose and xylose) were similar, sequential utilization was observed when both the sugars were present in the medium. The tolerance of Lipomyces starkeyi to the acid‐hydrolysis byproducts, furfural, 5‐hydroxy methyl furfural (HMF), vanillin, para‐hydroxy benzaldehyde (PHB), and syringaldehyde, was promising.CONCLUSIONThe inhibitory effects of 5‐hydroxy methyl furfural (HMF), vanillin, para‐hydroxy benzaldehyde (PHB), and syringaldehyde were not significant at concentrations up to 500 mg L−1; for furfural the threshold was 400 mg L−1. The fatty acid profiles of lipids were not affected by the presence of inhibitors in the medium. © 2016 Society of Chemical Industry
Outlook on optimizing ultramicroscopy imaging technique through optical characterization
Authors: Saghafi Saiedeh , Becker Klaus , Hahn Christian , Pende Marko , Jährling Nina , Wanis Martina , Sabdyusheva‐Litschauer Inna , Foroughipour Massih , Niendorf Axel , Dodt Hans‐Ulrich 
Published: December 2016

AbstractHere, we present an optically optimized system for static ultramicroscopy imaging technique. The unit for generating an ultra‐thin light sheet employs aspheric and meso‐optical elements (meso‐aspheric system). An analytical as well as an experimental comparison between the light sheet produced by the standard system (using a rectangular slit aperture and one cylindrical lens) and the one produced by our latest optimized system, which converts a symmetrical Gaussian beam into an ultra‐thin light sheet is presented. Using the new light sheet in combination with our objective equipped with a modulator unit to compensate the refractive index mismatch between air and mediums with indices of 1.45–1.56, we present high resolution images of various biological samples that were chemically cleared using different methods. They demonstrate a marked improvement in quality, contrast and resolution.
Elevated bile amylase level without pancreaticobiliary maljunction is a risk factor for gallbladder carcinoma
Authors: Fujimoto Takaaki , Ohtsuka Takao , Nakashima Yohei , Gotoh Yoshitaka , Date Kenjiro , Mori Yasuhisa , Sadakari Yoshihiko , Takahata Shunichi , Oda Yoshinao , Nakamura Masafumi 
Published: December 2016

AbstractBackgroundElevated bile amylase level in patients with pancreaticobiliary maljunction (PBM) or high confluence of pancreaticobiliary ducts (HCPBD) is well known as a risk factor for gallbladder carcinoma (GBC) development. However, the effects of occult pancreaticobiliary reflux (OPR), a condition characterized by high bile amylase level in the presence of an anatomically normal pancreaticobiliary junction, on GBC development remain unclear. The aim of this study was to assess the relationship between OPR and GBC.MethodsClinicopathological data of 52 patients who were preoperatively diagnosed with gallbladder (GB) tumor (22 malignant, 30 benign) were retrospectively reviewed. All of the patients underwent preoperative endoscopic retrograde cholangiopancreatography to evaluate pancreaticobiliary junction morphology and bile amylase level. The relationship between the histological diagnosis of GB lesions, and pancreaticobiliary junction morphology and bile amylase level were investigated.ResultsPancreaticobiliary maljunction, HCPBD, and normal pancreaticobiliary junction (NPJ) were identified in 12, nine, and 31 patients, respectively. The rates of GBC in patients with PBM, HCPBD, and NPJ were 58% (7/12), 67% (6/9), and 29% (9/31), respectively. Of the 31 patients with NPJ, 22 had OPR and nine of these had GBC. None of the patients with NPJ and normal bile amylase level had GBC. Additionally, among patients with NPJ, bile amylase level was significantly higher in patients with GBC than in patients with benign tumors.ConclusionsOccult pancreaticobiliary reflux, like PBM and HCPBD, is a risk factor for GBC development.
An evaluation of human ADME and mass balance studies using regular or low doses of radiocarbon
Authors: Roffel A.F. , van Marle S.P. , van Lier J.J. , Hartstra J. , van Hoogdalem E.‐J. 
Published: December 2016

There has been increased interest in conducting human absorption, distribution, metabolism, and excretion (ADME) studies with low doses (up to 0.1 MBq) as opposed to regular doses (1.85–3.7 MBq) of radiocarbon (14C). This is due to the fact that low‐dose human ADME studies may be conducted without dosimetry calculations and will lead to lower human radiation exposure. Here, we sought to compare the outcomes of low‐dose versus regular‐dose human ADME studies in healthy volunteers. Forty oral human ADME studies conducted at PRA were surveyed, among which 12 were low‐dose studies. The fraction of drug material absorbed was 67% ± 7% in the regular‐dose studies (data for 13 studies) versus 39% ± 16% in the low‐dose studies (data for 5 studies). The average total recovery of 14C in excreta was 93% ± 5% for regular‐dose studies, and 21 of 28 such studies showed recoveries more than 90%. For low‐dose studies, average total recovery was 89% ± 9%, and 6 of 12 studies showed recoveries more than 90%. Metabolite profiling was successful in all cases reported (13 regular‐dose studies and 5 low‐dose studies). There was no obvious relationship between the total recoveries of 14C in excreta and the proportion of 14C excreted in feces, or between the total recoveries and the plasma elimination half‐lives for parent or total 14C, neither in the low‐dose nor the regular‐dose studies. A significant correlation was found between the fraction absorbed and the recovery in feces in the low‐dose but not in the regular‐dose studies, and no correlation was found between the fractions absorbed and the total recoveries in both types of studies. Low‐dose studies were more often conducted on drugs that had a plasma elimination half‐life of parent drug more than 100 hours (5 of 12 studies) than regular‐dose studies (1 of 26 studies). We conclude that both low‐dose as well as regular‐dose human ADME studies provide adequate data to support decision making for further drug development.
Evaluation of soil moisture‐precipitation feedback at different time scales over Asia
Authors: Liu Di , Yu Zhongbo , Mishra Ashok K. 
Published: December 2016

ABSTRACTThe soil moisture‐precipitation (SM‐P) feedback process can affect the water and energy cycles at local to regional scale, subsequently affecting the water distribution in space and time. This study investigates SM‐P feedback at different time scales over Asia during boreal summer season based on the covariation between SM and P. In this article the positive (negative) feedback means positive (negative) statistical correlations between SM‐P. This is based on the statistical relationship and do not reflect physical process associated between SM and P. The Global Land Data Assimilation System (GLDAS) data, Climate Forecast System Reanalysis (CFSR) data and regional climate model, version 4 (RegCM4) simulations are adopted for analysis in this study. The results indicate a negative SM‐P relationship at a seasonal time scale over mid‐high latitudes of the study area whereas a positive but weak and spatial scattered correlation pattern is observed at the interannual time scale. A positive relationship is diagnosed over India, Indochina, and southeast China regions at seasonal (though weak) and interannual time scales. The positive and/or negative SM‐P correlation patterns observed at different time scales depends on the memory associated with seasonal precipitation and soil moisture. The strength of the SM‐P relationship seems to be influenced by the threshold behaviour of soil moisture, especially at the interannual time scale. This indicates that beyond a certain threshold in soil moisture anomalies likely to have significant influence on precipitation.
Less warming projected during heavy winter precipitation in the Cascades and Sierra Nevada
Authors: Rupp David E. , Li Sihan 
Published: December 2016

ABSTRACTLocal rates of warming from increased greenhouse gas concentrations can be different during heavy precipitation than during other times. This variable warming can influence precipitation extremes through the Clausius–Clapeyron relationship and modulate the rate of snowfall decline. Large ensembles of simulations from a regional climate model were used to project, with high signal‐to‐noise ratio, changes in the daily winter temperature versus precipitation intensity relationship from the contemporary period to a mid‐21st century scenario over the Cascades and Sierra Nevada of the United States. Warming rates decreased with increasing precipitation intensity over all montane regions, with the strongest relationship in the northern Cascades (1.2 °C less warming at 100 mm day−1 than at trace amounts). The relationship may be linked to the projected north Pacific meridional warming gradient, as the moisture of the largest precipitation events originates at lower latitudes where warming is less, though other factors may contribute.
Prediction of hERG Liability – Using SVM Classification, Bootstrapping and Jackknifing
Authors: Sun Hongmao , Huang Ruili , Xia Menghang , Shahane Sampada , Southall Noel , Wang Yuhong 
Published: December 2016

AbstractDrug‐induced QT prolongation leads to life‐threatening cardiotoxicity, mostly through blockage of the human ether‐à‐go‐go‐related gene (hERG) encoded potassium ion (K+) channels. The hERG channel is one of the most important antitargets to be addressed in the early stage of drug discovery process, in order to avoid more costly failures in the development phase. Using a thallium flux assay, 4,323 molecules were screened for hERG channel inhibition in a quantitative high throughput screening (qHTS) format. Here, we present support vector classification (SVC) models of hERG channel inhibition with the averaged area under the receiver operator characteristics curve (AUC‐ROC) of 0.93 for the tested compounds. Both Jackknifing and bootstrapping have been employed to rebalance the heavily biased training datasets, and the impact of these two under‐sampling rebalance methods on the performance of the predictive models is discussed. Our results indicated that the rebalancing techniques did not enhance the predictive power of the resulting models; instead, adoption of optimal cutoffs could restore the desirable balance of sensitivity and specificity of the binary classifiers. In an external validation set of 66 drug molecules, the SVC model exhibited an AUC‐ROC of 0.86, further demonstrating the utility of this modeling approach to predict hERG liabilities.
Mitochondrial capacity, muscle endurance, and low energy in friedreich ataxia
Authors: Bossie Hannah M. , Willingham T. Bradley , Schoick Robbi A. Van , O'Connor Patrick J. , McCully Kevin K. 
Published: December 2016

ABSTRACTIntroductionIn this study we noninvasively evaluated skeletal muscle mitochondrial capacity, muscle‐specific endurance, and energy/fatigue feelings in persons with Friedreich ataxia (FRDA) and able‐bodied controls (AB).MethodsForearm mitochondrial capacity was measured in FRDA (n = 16) and AB (n = 10) study participants using the rate of recovery of oxygen consumption after electrical stimulation with near‐infrared spectroscopy. Mechanomyography (MMG) assessed muscle endurance after electrical stimulation for 3 minutes at 2 Hz, 4 Hz, and 6 Hz. Validated scales assessed disease severity and energy/fatigue feelings.ResultsGroups did not differ in mitochondrial capacity (FRDA and AB: 1.8 ± 0.3 L/min). The difference in muscle endurance at 6 Hz was lower by 19.2% in the FRDA group (group effect: P < 0.001). Feelings of physical energy were 34% lower in FRDA group. In FDRA muscle, endurance was positively related to mitochondrial capacity (r = 0.59, P = 0.03), and disease severity was negatively related to mitochondrial capacity (r = –0.55, P = 0.04) and muscle endurance (r = –0.60, P = 0.01).ConclusionNon‐invasive measures of skeletal muscle mitochondrial capacity and muscle‐specific endurance are useful in monitoring FRDA. Muscle Nerve 56: 773–779, 2017
Microstructural models for diffusion MRI in breast cancer and surrounding stroma: an ex vivo study
Authors: Bailey Colleen , Siow Bernard , Panagiotaki Eleftheria , Hipwell John H. , Mertzanidou Thomy , Owen Julie , Gazinska Patrycja , Pinder Sarah E. , Alexander Daniel C. , Hawkes David J. 
Published: December 2016

The diffusion signal in breast tissue has primarily been modelled using apparent diffusion coefficient (ADC), intravoxel incoherent motion (IVIM) and diffusion tensor (DT) models, which may be too simplistic to describe the underlying tissue microstructure. Formalin‐fixed breast cancer samples were scanned using a wide range of gradient strengths, durations, separations and orientations. A variety of one‐ and two‐compartment models were tested to determine which best described the data. Models with restricted diffusion components and anisotropy were selected in most cancerous regions and there were no regions in which conventional ADC or DT models were selected. Maps of ADC generally related to cellularity on histology, but maps of parameters from more complex models suggest that both overall cell volume fraction and individual cell size can contribute to the diffusion signal, affecting the specificity of ADC to the tissue microstructure. The areas of coherence in diffusion anisotropy images were small, approximately 1 mm, but the orientation corresponded to stromal orientation patterns on histology.
A new approach to solve complex valued systems arising from the solution of Maxwell equations in the frequency domain through real‐equivalent formulations
Authors: Marioni L. , R. Alves Z. J. , Hachem E. , Bay F. 
Published: December 2016

SummaryThe purpose of this article is to propose algebraic techniques to solve symmetric complex‐valued systems. In particular, we focus on the systems which arise from the modeling of electromagnetic fields in the frequency domain. These systems usually present a very ill‐conditioned number, so specific preconditioning techniques are supposed to be used. Finally, both analytical and numerical reference tests are proposed on the simple case of the magnetic field produced by a solenoid containing conductive or non‐conducting materials.
Anxiety independently contributes to elevated inflammation in humans with obesity
Authors: Pierce Gary L. , Kalil Graziela Z. , Ajibewa Tiwaloluwa , Holwerda Seth W. , Persons Jane , Moser David J. , Fiedorowicz Jess G. 
Published: December 2016

ObjectiveAnxious and depressive states are associated with increased cardiovascular disease (CVD) risk and a proinflammatory phenotype, although the latter appears to be at least partially explained by adiposity. It was hypothesized that depression and anxiety would be associated with elevated inflammation independent of adiposity in persons with obesity at high risk of CVD.MethodsThis study explored the relation between baseline anxiety as measured by the Beck Anxiety Inventory and depression as measured by the Beck Depression Inventory‐II and baseline serum c‐reactive protein (CRP) in a cross‐sectional sample of 100 participants [mean (SD) age 57.8 (7.7) years; 64% female] with obesity [mean (SD) body mass index, BMI 37.3 (5.5) kg/m2] enrolled in a clinical trial for pharmacological weight loss.ResultsBeck Anxiety Inventory, but not Beck Depression Inventory‐II, scores were significantly correlated with CRP (ρ = 0.28, P = 0.005). BMI was also highly correlated with CRP (ρ = 0.42, P < 0.0001). In multivariate models, the relation between anxiety and CRP remained significant (P = 0.038), independent of BMI, age, and sex.ConclusionsAnxiety, but not depression, was associated with elevated inflammation in persons with obesity beyond that attributable to higher BMI. Further study is warranted to assess whether anxiety represents a potential therapeutic target to mitigate corresponding CVD risk associated with elevated inflammation in persons with obesity.
Dissecting the relationship between obesity and hyperinsulinemia: Role of insulin secretion and insulin clearance
Authors: Kim Mee Kyoung , Reaven Gerald M. , Kim Sun H. 
Published: December 2016

ObjectiveThe aim of this study was to better delineate the complex interrelationship among insulin resistance (IR), secretion rate (ISR), and clearance rate (ICR) to increase plasma insulin concentrations in obesity.MethodsHealthy volunteers (92 nondiabetic individuals) had an insulin suppression test to measure IR and graded‐glucose infusion test to measure ISR and ICR. Obesity was defined as a body mass index (BMI) ≥30 kg/m2, and IR was defined as steady‐state plasma glucose (SSPG) ≥10 mmol/L during the insulin suppression test. Plasma glucose and insulin concentrations, ISR, and ICR were compared in three groups: insulin sensitive/overweight; insulin sensitive/obesity; and insulin resistant/obesity.ResultsCompared with the insulin‐sensitive/overweight group, the insulin‐sensitive/obesity had significantly higher insulin area under the curve (AUC) and ISR AUC during the graded‐glucose infusion test (P < 0.001). Glucose AUC and ICR were similar. The insulin‐resistant/obesity group had higher insulin AUC and ISR AUC compared with the insulin‐sensitive/obesity but also had higher glucose AUC and decreased ICR (P < 0.01). In multivariate analysis, both BMI and SSPG were significantly associated with ISR.ConclusionsPlasma insulin concentration and ISR are increased in individuals with obesity, irrespective of degree of IR, but a decrease in ICR is confined to the subset of individuals with IR.