bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dorsal hippocampus is necessary for visual categorization in rats
Authors: Kim Jangjin , Castro Leyre , Wasserman Edward A. , Freeman John H. 
Published: February 2018

AbstractThe hippocampus may play a role in categorization because of the need to differentiate stimulus categories (pattern separation) and to recognize category membership of stimuli from partial information (pattern completion). We hypothesized that the hippocampus would be more crucial for categorization of low‐density (few relevant features) stimuli–due to the higher demand on pattern separation and pattern completion–than for categorization of high‐density (many relevant features) stimuli. Using a touchscreen apparatus, rats were trained to categorize multiple abstract stimuli into two different categories. Each stimulus was a pentagonal configuration of five visual features; some of the visual features were relevant for defining the category whereas others were irrelevant. Two groups of rats were trained with either a high (dense, n = 8) or low (sparse, n = 8) number of category‐relevant features. Upon reaching criterion discrimination (≥75% correct, on 2 consecutive days), bilateral cannulas were implanted in the dorsal hippocampus. The rats were then given either vehicle or muscimol infusions into the hippocampus just prior to various testing sessions. They were tested with: the previously trained stimuli (trained), novel stimuli involving new irrelevant features (novel), stimuli involving relocated features (relocation), and a single relevant feature (singleton). In training, the dense group reached criterion faster than the sparse group, indicating that the sparse task was more difficult than the dense task. In testing, accuracy of both groups was equally high for trained and novel stimuli. However, both groups showed impaired accuracy in the relocation and singleton conditions, with a greater deficit in the sparse group. The testing data indicate that rats encode both the relevant features and the spatial locations of the features. Hippocampal inactivation impaired visual categorization regardless of the density of the category‐relevant features for the trained, novel, relocation, and singleton stimuli. Hippocampus‐mediated pattern completion and pattern separation mechanisms may be necessary for visual categorization involving overlapping irrelevant features.
Mst1/2 Kinases Modulate Glucose Uptake for Osteoblast Differentiation and Bone Formation
Authors: Li Wenling , Deng Yujie , Feng Bo , Mak Kingston King-Lun 
Published: February 2018

ABSTRACT

Bone formation and bone homeostasis are energy-expensive processes. How they are being regulated by energy needs is not completely understood. This is of high clinical importance because diabetic-induced bone loss is common whereas the underlying mechanisms are unclear. Here, we show that Mst1/2 are important regulators for glucose uptake during osteoblast differentiation. Genetically removal of both Mst1/2 kinases simultaneously in mice in early and mature osteoblasts inhibits bone formation and bone remodeling, respectively. We found that the activity of Mst1/2 kinases is sensitive to glucose levels, and in turn, regulates glucose uptake by stabilizing key glucose transporter Glut1. In the absence of Mst1/2 kinases, Glut1 expression is loss and results in AMP-dependent protein kinase (AMPK) activation and subsequent proteasomal degradation of Runx2. The streptozotocin (STZ)-induced diabetic mouse model also recapitulates similar changes in the bone tissues. In addition, Glut1 expression regulated by Mst1/2 kinases is independent of Yap/Taz expression. Our results unravel new mechanistic insights into the orchestration of glucose level and bone homeostasis. © 2018 American Society for Bone and Mineral Research.
Impact of SLCO1B1 Genotype on Pediatric Simvastatin Acid Pharmacokinetics
Authors: Wagner Jonathan B. , Abdel‐Rahman Susan , Van Haandel Leon , Gaedigk Andrea , Gaedigk Roger , Raghuveer Geetha , Kauffman Ralph , Leeder J. Steven 
Published: February 2018

AbstractThis study investigated the impact of allelic variation in SLCO1B1, a gene encoding for the liver‐specific solute carrier organic anion transporter family member 1B1 protein (SLCO1B1), on simvastatin and simvastatin acid (SVA) systemic exposure in children and adolescents. Participants (8–20 years old) with at least 1 variant SLCO1B1 c.521T>C allele (521TC, n = 15; 521CC, n = 2) and 2 wild‐type alleles (521TT, n = 15) completed a single oral dose pharmacokinetic study. At equivalent doses, SVA exposure was 6.3‐ and 2.5‐fold greater in 521CC and TC genotypes relative to 521TT (Cmax, 2.1 ± 0.2 vs 1.0 ± 0.5 vs 0.4 ± 0.3 ng/mL; P < .0001; and AUC, 12.1 ± 0.3 vs 4.5 ± 2.5 vs 1.9 ± 1.8 ng·h/mL; P < .0001). The impact of the SLCO1B1 c.521 genotype was more pronounced in children, although considerable interindividual variability in SVA exposure was observed within genotype groups. In addition, SVA systemic exposure was negligible in 25% of pediatric participants. Further investigation of the ontogeny and genetic variation of SVA formation and SLCO1B1‐mediated hepatic uptake is necessary to better understand the variability in SVA exposure in children and its clinical consequences.
Label‐free monitoring of inflammatory tissue conditions using a carrageenan‐induced acute inflammation rat model
Authors: Lee Seung Ho , Lee Sang Hwa , Shin Jae‐Ho , Choi Samjin 
Published: February 2018

AbstractAlthough the confirmation of inflammatory changes within tissues at the onset of various diseases is critical for the early detection of disease and selection of appropriate treatment, most therapies are based on complex and time‐consuming diagnostic procedures. Raman spectroscopy has the ability to provide non‐invasive, real‐time, chemical bonding analysis through the inelastic scattering of photons. In this study, we evaluate the feasibility of Raman spectroscopy as a new, easy, fast, and accurate diagnostic method to support diagnostic decisions. The molecular changes in carrageenan‐induced acute inflammation rat tissues were assessed by Raman spectroscopy. Volumes of 0 (control), 100, 150, and 200 µL of 1% carrageenan were administered to rat hind paws to control the degree of inflammation. The prominent peaks at [1,062, 1,131] cm−1 and [2,847, 2,881] cm−1 were selected as characteristic measurements corresponding to the C–C stretching vibrational modes and the symmetric and asymmetric C–H (CH2) stretching vibrational modes, respectively. Principal component analysis of the inflammatory Raman spectra enabled graphical representation of the degree of inflammation through principal component loading profiles of inflammatory tissues on a two‐dimensional plot. Therefore, Raman spectroscopy with multivariate statistical analysis represents a promising method for detecting biomolecular responses based on different types of inflammatory tissues.
A time to trust? The buffering effect of trust and its temporal variations in the context of high‐reliability teams
Authors: Burtscher Michael J. , Meyer Bertolt , Jonas Klaus , Feese Sebastian , Tröster Gerhard 
Published: February 2018

SummaryThis study aims to further clarify the functionality of job resources in the context of high‐reliability teams. Combining extant stress models with theoretical considerations from team research, we address temporal variations in the buffering effect of trust in teammates. We hypothesize that trust buffers the negative effect of objective physical activity on perceived strain and that this buffering effect is more pronounced during later performance episodes (i.e., when employees complete a series of temporally distinguishable tasks). We tested the hypotheses with a sample of professional firefighters who completed a sequence of 3 performance episodes in a high‐fidelity simulation environment. Each participant was equipped with a smartphone capturing individual motion activity, which we used as an indicator of physical activity. In line with our hypotheses, multilevel modeling revealed a buffering effect of trust on the relationship between physical activity and perceived strain. Importantly, this buffering effect was more pronounced in the second performance episode as compared with the first performance episode. Our findings add a temporal perspective to the understanding of the effectiveness of job resources. In addition, the current study illustrates the usefulness of smartphones for obtaining behavioral data in a naturalistic setting.
Lower‐limb muscle function during gait in varus mal‐aligned osteoarthritis patients
Authors: Sritharan Prasanna , Lin Yi‐Chung , Richardson Sara E. , Crossley Kay M. , Birmingham Trevor B. , Pandy Marcus G. 
Published: February 2018

ABSTRACTThis study quantified the contributions by muscular, gravitational and inertial forces to the ground reaction force (GRF) and external knee adduction moment (EKAM) for knee osteoarthritis (OA) patients and controls walking at similar speeds. Gait data for 39 varus mal‐aligned medial knee OA patients and 15 controls were input into musculoskeletal models to calculate the contributions of individual muscles and gravity to the fore‐aft (progression), vertical (support), and mediolateral (balance) GRF, and the EKAM. The temporal patterns of contributions to GRF and EKAM were similar between the groups. Magnitude differences in GRF contributions were small but some reached significance. Peak GRF contributions were lower in patients except hamstrings in early‐stance progression (p < 0.001) and gastrocnemius in late‐stance progression (p < 0.001). Both EKAM peaks were higher in patients, due mainly to greater adduction contribution from gravity (p < 0.001) at the first peak, and lower abduction contributions from soleus (p < 0.001) and gastrocnemius (p < 0.001) at the second peak. Gluteus medius contributed most to EKAM in both groups, but was higher in patients during mid‐stance only (p < 0.001). Differences in GRF contributions were attributed to altered quadriceps‐hamstrings action as well as compensatory adaptation of the ankle plantarflexors to reduced gluteus medius action. The large effect of varus mal‐alignment on the frontal‐plane moment arms of the gravity, soleus, and gastrocnemius GRF contributions about the knee explained greater patient EKAM. Our results shed further light on how the EKAM contributes to altered knee‐joint loads in OA and why some interventions may affect different portions of the EKAM waveform. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:2157–2166, 2018.
A Zwitterionic Surfactant Bearing Unsaturated Tail for Enhanced Oil Recovery in High‐Temperature High‐Salinity Reservoirs
Authors: Kamal Muhammad Shahzad , Shakil Hussain Syed M. , Fogang Lionel Talley 
Published: February 2018

AbstractHigh‐temperature/high‐salinity (HTHS) reservoirs contain a significant fraction of the world's remaining oil in place and are potential candidates for enhanced oil recovery (EOR). Selection of suitable surfactants for such reservoirs is a challenging task. In this work, two synthesized zwitterionic surfactants bearing a saturated and an unsaturated tail, namely 3‐(N‐stearamidopropyl‐N,N‐dimethyl ammonium) propanesulfonate and 3‐(N‐oleamidopropyl‐N,N‐dimethyl ammonium) propanesulfonate, respectively, were evaluated. The surfactant with the unsaturated tail showed excellent solubility in synthetic seawater (57,643 ppm) and in formation brine (213,734 ppm). However, the unsaturated surfactant with a saturated tail showed poor solubility, and therefore it was not evaluated further. The thermal stability of the synthesized unsaturated surfactant solution in seawater was evaluated by heating the solution at 90 °C in a sealed aging tube for 2 weeks. The thermal stability of the unsaturated surfactant was confirmed by FTIR and NMR analysis of the aged samples at such harsh conditions. The critical micelle concentration (CMC) of the synthesized unsaturated surfactant in seawater was 1.02 × 10−4 mol L−1, while the surface tension at CMC was 30 mN m−1. The synthesized unsaturated surfactant was able to reduce the oil–water interfacial tension to ~10−1 mN m−1 at different conditions. A commercial copolymer of acrylamide and 2‐acrylamido‐2‐methylpropane sulfonic acid (AM‐AMPS) was tested for EOR applications in HTHS conditions. The addition of the synthesized unsaturated surfactant to the AM‐AMPS copolymer increased the viscosity of the system. The increase in oil recovery by injecting the unsaturated surfactant solution and the surfactant–polymer mixture in solution was 8 and 21%, respectively. The excellent properties of the synthesized unsaturated surfactant show that surfactants with an unsaturated tail can be an excellent choice for HTHS reservoirs.
Quality of preoperative pelvic computed tomography (CT) and magnetic resonance imaging (MRI) for rectal cancer in a region in Ontario: A retrospective population‐based study
Authors: Bogach Jessica , Tsai Scott , Zbuk Kevin , Wong Raimond , Grubac Vanja , Coates Angela , Pond Gregory R. , Simunovic Marko 
Published: February 2018

Background and ObjectivesTreatment decisions for rectal cancer rely on preoperative staging with CT and MRI scans. We assessed the quality of such scans in a region of Ontario.MethodsWe retrospectively collected data for patients undergoing rectal cancer surgery between July 2011 and December 2014. We measured three aspects of quality: use; comprehensiveness of reporting T‐category, N‐category, mesorectal fascia (MRF) status; and in non‐radiated patients sensitivity and specificity of reports for relevant elements.ResultsA total of 559 patients underwent major rectal cancer surgery. Preoperative staging with CT and MRI was performed in 93% and 50% of patients. CT scan reports provided information on T‐category, N‐category, and MRF status in 41%, 92%, and 16% of cases. These same elements were reported on MRI in 88%, 93%, and 62% of cases. CT scan sensitivity and specificity was 80% and 80% for T‐category, and 85% and 39% for N‐category. MRI sensitivity and specificity was 75% and 81% for T‐category, 79% and 37% for N‐category, and 33% and 89% for MRF status.ConclusionIn this region of Ontario, pre‐operative MRI was underutilized, CT reporting of MRF status was low, and when reported sensitivity and specificity of T‐ and N‐category were similar for CT and MRI.
Is tissue still the issue? Lobectomy for suspicious lung nodules without confirmation of malignancy
Authors: Kaaki Suha , Kidane Biniam , Srinathan Sadeesh , Tan Lawrence , Buduhan Gordon 
Published: February 2018

BackgroundHistologic confirmation of malignancy has been indicated for a suspicious lung nodule prior to resection. The purpose of this study was to determine whether or not foregoing routine tissue biopsy increased the incidence of lobectomy for benign lesions.MethodsRetrospective cohort of 256 patients who underwent thoracoscopic or open lobectomy for a confirmed or suspected pulmonary malignancy, with or without tissue diagnosis. Clinical, radiographic, and pathologic data were compared.ResultsAmong 256 patients, 127 had attempted biopsy (group A) and 129 had no biopsy procedure (group B). There was no significant difference in the incidence of benign resections between the groups (Group A = 4 (3.2%) benign pathology vs group B = 9 (7.0%; P = 0.16). Group B had significantly lower operative time (127.1 vs 112.3 minutes; P = 0.004) and intraoperative complications (23 vs 37 patients; P = 0.03). There was a trend toward longer hospital stay and surgical waiting time in group A (6.6 vs 5.2 days, P = 0.24; 92.4 vs 66.2 days; P = 0.14, respectively).ConclusionForegoing biopsies and proceeding to lobectomy in selected patients with suspicious lung nodules is safe, did not increase the incidence of resected benign pathology, and may decrease surgical wait time. Patients should be carefully evaluated and counseled.
Comparison of two novel staging systems with the TNM system in predicting stage III colon cancer survival
Authors: Walker Richard , Wood Trevor , LeSouder Emily , Cleghorn Michelle , Maganti Manjula , MacNeill Andrea , Quereshy Fayez A. 
Published: February 2018

Background and ObjectivesAdaptations of the TNM staging system that incorporate the Lymph Node Ratio (LNR) have been proposed for stage III colon cancer. This study compared the concordance of two novel staging systems and the TNM system with observed survival outcomes in stage III patients.MethodsA review of patients who underwent surgery for stage III colon cancer between January 2002 and April 2015 at a tertiary care centre was performed. The Kaplan‐Meier method was used to estimate the 5‐year overall (OS) and disease free survival (DFS) rates, and the concordance probability was calculated to evaluate the discriminatory power of the staging systems.ResultsTwo hundred and sixty‐one patients were identified. For TNM stages IIIA, IIIB, and IIIC, 5‐year OS was 83.4%, 67.6%, and 38.3%, respectively (P < 0.001). All three staging systems were independently predictive of OS and DFS (P < 0.001). However, the novel staging system by Sugimoto et al18 was the most favourable prognostic tool, with a concordance of 0.646 for DFS and 0.659 for OS.ConclusionsThe novel staging system by Sugimoto et al18 was superior to the TNM system. Incorporating LNR into staging models for node positive colon cancers may improve survival information available to patients and potentially aid treatment decisions.
Postoperative low hepatitis C virus load predicts long‐term outcomes after hepatectomy for hepatocellular carcinoma
Authors: Sasaki Kazunari , Shindoh Junichi , Nishioka Yujiro , Sugawara Toshitaka , Margonis Georgios A. , Andreatos Nikolaos , Pawlik Timothy M. , Hashimoto Masaji 
Published: February 2018

BackgroundPreoperative hepatitis C virus (HCV) viral load is known to predict long‐term outcomes after hepatectomy for HCV‐related hepatocellular carcinoma (HCC). This study sought to examine the hypothesis that postoperative and preoperative HCV viral‐load have similar prognostic implications, as well as determine a target viral‐load that will improve long‐term postoperative outcomes.MethodOne hundred and eighty‐one patients who underwent curative hepatectomy for HCV‐related HCC were divided into five groups according to time‐weighted average viral load. The cumulative‐recurrence curves of the five groups were compared to identify prognostic trends. The optimal cut‐off viral load value related to recurrence was also investigated.ResultsThe five cumulative‐recurrence curves were separated into two clusters according to viral load. Patients with a negative viral load had comparable recurrence curves to patients with the lowest viral‐load (P = 0.907); both of these patient groups had more favorable outcomes than patients with a viral load categorized in the other groups (all P < 0.050). The optimal cut‐off based on maximum HR method (> or ≤4.0 log10 IU/mL) was a strong prognostic indicator of recurrence in multivariate analysis (HR 3.09; 95%CI 1.96‐5.04; P < 0.001).ConclusionPostoperative HCV viral load correlated with long‐term surgical outcomes. A low viral load (≤4.0 log10 IU/mL) independently predicted better long‐term outcomes.
Importance of wide re‐resection in adult spermatic cord sarcomas: Report on oncologic outcomes at a single institution
Authors: Murray Katie S. , Vertosick Emily A. , Spaliviero Massimiliano , Mashni Joseph W. , Sjoberg Daniel D. , Alektiar Kaled M. , Herr Harry W. , Russo Paul , Coleman Jonathan A. 
Published: February 2018

Background and ObjectivesWe evaluated the effect of re‐resection with wide margins (undertaken because initial resection performed elsewhere was incomplete) on survival in patients with spermatic cord sarcoma (SCS).MethodsAfter excluding those with metastatic disease and those not undergoing surgical intervention, the records of 72 consecutive patients treated for SCS between 1981 and 2011 at Memorial Sloan Kettering Cancer Center were reviewed. Recurrence‐free survival (RFS) and cancer‐specific survival were calculated using the Kaplan‐Meier method for comparing between the 48 patients who underwent wide re‐resection (WRR) within 5 months of diagnosis and the 24 who did not. The relationship of age, tumor size, tumor histology, adjuvant radiation, and wide re‐resection with recurrence and death was assessed by univariate Cox regression.ResultsWRR significantly improved RFS (hazard ratio [HR] 0.16, 95%CI 0.07‐0.37; P < 0.0001), despite the fact that patients receiving WRR had higher‐grade disease. Tumor‐positive margins upon WRR were strongly associated with both disease recurrence (HR 5.56; 95%CI 1.14‐27.11, P = 0.034) and death from cancer (HR 6.16, 95%CI 1.25‐30.29; P = 0.025).ConclusionsA WRR with negative margins is effective in the management of patients with SCS and leads to improved RFS.
The epidemiology and prophylaxis of infectious verbal pomposity
Authors: Gregory Martin W. 
Published: February 2018

ABSTRACTThere are two kinds of scientific writing: that which is intended to be read, and that which is intended merely to be cited. The latter tends to be infected with infectious verbal pomposity (IVP). The disease is ubiquitous, but often undiagnozed, with the result that infection spreads to writing of the first type. This paper summarizes our knowledge of the condition, presents a few clinical cases, and offers a new approach to its control.
Effect of displacement amplitude on fretting wear of 304 stainless steel in air and sea water
Authors: Fan Na , Wang Yunxia , Wang Qiufeng , Wang Mengjiao , Yan Fengyuan 
Published: February 2018

AbstractThe fretting wear behaviours of 304 stainless steel at different displacement amplitudes were investigated by using a SRV‐IV fretting tester in air and sea water, respectively. In air, the friction coefficient as well as the fretting damage of 304 stainless steel increased with the increase of displacement amplitude, and the fretting regime changed from partial slip regime to gross slip regime. Correspondingly, the wear mechanisms transformed from local fatigue and slight oxidation to the combination damages of adhesion wear, abrasive wear, and oxidation. Compared with the dry friction conditions, sea water had a strong effect on fretting behaviour of 304 stainless steel. Adhesion wear was effectively suppressed due to the cooling and lubrication effect of sea water. Therefore, friction coefficient and wear depth decreased significantly. And the damages of 304 stainless steel in sea water were mainly caused by abrasive wear, slight adhesion wear, and corrosion wear.
Film building in circular EHL contact lubricated by oil droplet groups
Authors: Guo Feng , Li Shu‐Yi , Liu Cheng‐Long , Li Xin‐Ming , Liu Xiao‐Ling 
Published: February 2018

AbstractNumerical calculations have been conducted to study elastohydrodynamic lubrication (EHL) with lubricant in the form of droplet groups, which was aimed to simulate air‐oil lubrication. Two types of lubricant droplet distributions, ie, 1 row of droplets along the centreline of the contact or 2 rows of droplets on each side of the centreline, were adopted. The results showed that continuous EHL film could be obtained in spite that discontinuous lubricant droplets were supplied, which is attributed to the squeeze spread and rejoining of the droplets at the inlet. The total effective lubrication time for full film lubrication has a linear correlation with the number of the droplets, and there exists an optimum droplet spacing distance for continuous full film lubrication. For a constant volume of lubricant, calculations indicated that for most efficient lubrication, there is a trade‐off between the droplet size and the number of droplets divided.