bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dopamine transporter availability in clinically normal aging is associated with individual differences in white matter integrity
Authors: Rieckmann Anna , Hedden Trey , Younger Alayna P. , Sperling Reisa A. , Johnson Keith A. , Buckner Randy L. 
Published: November 2015

AbstractAging‐related differences in white matter integrity, the presence of amyloid plaques, and density of biomarkers indicative of dopamine functions can be detected and quantified with in vivo human imaging. The primary aim of the present study was to investigate whether these imaging‐based measures constitute independent imaging biomarkers in older adults, which would speak to the hypothesis that the aging brain is characterized by multiple independent neurobiological cascades. We assessed MRI‐based markers of white matter integrity and PET‐based marker of dopamine transporter density and amyloid deposition in the same set of 53 clinically normal individuals (age 65–87). A multiple regression analysis demonstrated that dopamine transporter availability is predicted by white matter integrity, which was detectable even after controlling for chronological age. Further post‐hoc exploration revealed that dopamine transporter availability was further associated with systolic blood pressure, mirroring the established association between cardiovascular health and white matter integrity. Dopamine transporter availability was not associated with the presence of amyloid burden. Neurobiological correlates of dopamine transporter measures in aging are therefore likely unrelated to Alzheimer's disease but are aligned with white matter integrity and cardiovascular risk. More generally, these results suggest that two common imaging markers of the aging brain that are typically investigated separately do not reflect independent neurobiological processes. Hum Brain Mapp 37:621–631, 2016. © 2015 Wiley Periodicals, Inc.
Obtainment and partial characterization of biodegradable gelatin films with tannic acid, bentonite and glycerol
Authors: Ortiz‐Zarama Maria A , Jiménez‐Aparicio Antonio R , Solorza‐Feria Javier 
Published: November 2015

AbstractBACKGROUNDResearch studies concerning the overall effect of the addition of plasticizers, cross‐linking and strengthening agents in gelatin film‐forming mixtures are very scarce. Also, there are no studies focused on the interactions among their individual components, or showing what sort of effects they might cause all together. A gelatin film obtained from a composite consisting of tannic acid, bentonite and glycerol was evaluated. Nine gelatin films were manufactured by the casting method, using these materials, following a 23 factorial design with five replicates on the central point.RESULTSThe interactions among gelatin, tannic acid and bentonite caused a decrease in hydrogen bonds, while the polar groups of the gelatin chains were less exposed to interactions with water molecules. There was an increase in temperature and enthalpy of gelatin denaturation, due to increasing tannic acid and bentonite concentration. Tactoids were found in the gelatin films, caused mainly by bentonite polydispersion.CONCLUSIONSA synergistic effect among tannic acid, bentonite and glycerol, which overall improved the measured gelatin film properties, was found. The best film formulation was that with 40, 150 and 250 g kg−1 gelatin of tannic acid, bentonite and glycerol respectively, displaying a tensile strength of 38 MPa, an elongation at break of 136%, water vapor permeability of 1.28 × 10−12 g (Pa s m)−1 and solubility of 23.4%. © 2015 Society of Chemical Industry
Detection of human papillomavirus in laryngeal squamous cell carcinoma: Systematic review and meta‐analysis
Authors: Gama Ricardo Ribeiro , Carvalho André Lopes , Filho Adhemar Longatto , Scorsato Anderson Paulo , López Rossana V. Mendoza , Rautava Jaana , Syrjänen Stina , Syrjänen Kari 
Published: November 2015

BackgroundRecent studies have reported a human papillomavirus (HPV) prevalence of 20% to 30% in laryngeal squamous cell carcinoma (LSCC), although clinical data on HPV involvement remain largely inconsistent, ascribed by some to differences in HPV detection methods or in geographic origin of the studies.ObjectiveTo perform a systematic review and formal meta‐analysis of the literature reporting on HPV detection in LSCC.MethodsLiterature was searched from January 1964 until March 2015. The effect size was calculated as event rates (95% confidence interval [CI]), with homogeneity testing using Cochran's Q andI2statistics. Meta‐regression was used to test the impact of study‐level covariates (HPV detection method, geographic origin) on effect size. Potential publication bias was estimated using funnel plot symmetry.ResultsOne hundred seventy nine studies were eligible, comprising a sample size of 7,347 LSCCs from different geographic regions. Altogether, 1,830 (25%) cases tested HPV‐positive considering all methods, with effect size of 0.269 (95% CI: 0.242 to 0.297; random‐effects model). In meta‐analysis stratified by the 1) HPV detection technique and 2) geographic study origin, the between‐study heterogeneity was significant only for geographic origin (P= .0001). In meta‐regression, the HPV detection method (P= .876) or geographic origin (P= .234) were not significant study‐level covariates. Some evidence for publication bias was found only for studies from North America and those using non–polymerase chain reaction methods, with a marginal effect on adjusted point estimates for both.ConclusionsVariability in HPV detection rates in LSCC is explained by geographic origin of study but not by HPV detection method. However, they were not significant study‐level covariates in formal meta‐regression.Level of EvidenceNALaryngoscope, 126:885–893, 2016
Breathing air to save energy – new insights into the ecophysiological role of high‐affinity [NiFe]‐hydrogenase in Streptomyces avermitilis
Authors: Liot Quentin , Constant Philippe 
Published: November 2015

AbstractThe Streptomyces avermitilis genome encodes a putative high‐affinity [NiFe]‐hydrogenase conferring the ability to oxidize tropospheric H2 in mature spores. Here, we used a combination of transcriptomic and mutagenesis approaches to shed light on the potential ecophysiological role of the enzyme. First, S. avermitilis was either exposed to low or hydrogenase‐saturating levels of H2 to investigate the impact of H2 on spore transcriptome. In total, 1293 genes were differentially expressed, with 1127 and 166 showing lower and higher expression under elevated H2 concentration, respectively. High H2 exposure lowered the expression of the Sec protein secretion pathway and ATP‐binding cassette‐transporters, with increased expression of genes encoding proteins directing carbon metabolism toward sugar anabolism and lower expression of NADH dehydrogenase in the respiratory chain. Overall, the expression of relA responsible for the synthesis of the pleiotropic alarmone ppGpp decreased upon elevated H2 exposure, which likely explained the reduced expression of antibiotic synthesis and stress response genes. Finally, deletion of hhySL genes resulted in a loss of H2 uptake activity and a dramatic loss of viability in spores. We propose that H2 is restricted to support the seed bank of Streptomyces under a unique survival–mixotrophic energy mode and discuss important ecological implications of this finding.
Dependent personality, separation anxiety disorder and other anxiety disorders in OCD
Authors: Mroczkowski M. M. , Goes F. S. , Riddle M. A. , Grados M. A. , Bienvenu O. J. , Greenberg B. D. , Fyer A. J. , McCracken J. T. , Rauch S. L. , Murphy D. L. , Knowles J. A. , Piacentini J. , Cullen B. , Rasmussen S. A. , Pauls D. L. , Nestadt G. , Samuels J. 
Published: November 2015

AbstractBackgroundThe purpose of this study was to investigate whether dependent personality and/or general personality dimensions might explain the strong relationships between separation anxiety disorder (Sep‐AD) and three other anxiety disorders (agoraphobia, panic disorder and social anxiety disorder) in individuals with obsessive compulsive disorder (OCD).MethodsUsing data from 509 adult participants collected during the OCD Collaborative Genetic Study, we used logistic regression models to evaluate the relationships between Sep‐AD, dependent personality score, general personality dimensions and three additional anxiety disorders.ResultsThe dependent personality score was strongly associated with Sep‐AD and the other anxiety disorders in models adjusted for age at interview, age at onset of OC symptoms and worst ever OCD severity score. Several general personality dimensions, especially neuroticism, extraversion and conscientiousness, were also related to Sep‐AD and the other anxiety disorders. Sep‐AD was not independently related to these anxiety disorders, in multivariate models including general personality and dependent personality disorder scores.ConclusionsThe results suggest that Sep‐AD in childhood and these other anxiety disorders in adulthood are consequences of dependent personality disorder (for agoraphobia and panic disorder) or introversion (for social phobia). It is unknown whether these results would be similar in a non‐OCD sample. Copyright © 2015 John Wiley & Sons, Ltd.
Sample selection bias and Heckman models in strategic management research
Authors: Certo S. Trevis , Busenbark John R. , Woo Hyun‐soo , Semadeni Matthew 
Published: November 2015

Research summary: The use of Heckman models by strategy scholars to resolve sample selection bias has increased by more than 700 percent over the last decade, yet significant inconsistencies exist in how they have applied and interpreted these models. In view of these differences, we explore the drivers of sample selection bias and review how Heckman models alleviate it. We demonstrate three important findings for scholars seeking to use Heckman models: First, the independent variable of interest must be a significant predictor in the first stage of a model for sample selection bias to exist. Second, the significance of lambda alone does not indicate sample selection bias. Finally, Heckman models account for sample‐induced endogeneity, but are not effective when other sources of endogeneity are present.Managerial summary: When nonrandom samples are used to test statistical relationships, sample selection bias can lead researchers to flawed conclusions that can, in turn, negatively impact managerial decision‐making. We examine the use of Heckman models, which were designed to resolve sample selection bias, in strategic management research and highlight conditions when sample selection bias is present as well as when it is not. We also distinguish sample selection bias, a form of omitted variable (OV) bias, from more traditional OV bias, emphasizing that it is possible for models to have sample selection bias, traditional OV bias, or both. Accurately identifying the type(s) of OV bias present is essential to effectively correcting it. We close with several recommendations to improve practice surrounding the use of Heckman models. Copyright © 2015 John Wiley & Sons, Ltd.
Specification of anteroposterior axis by combinatorial signaling during Xenopus development
Authors: Carron Clémence , Shi De‐Li 
Published: November 2015

The specification of anteroposterior (AP) axis is a fundamental and complex patterning process that sets up the embryonic polarity and shapes a multicellular organism. This process involves the integration of distinct signaling pathways to coordinate temporal–spatial gene expression and morphogenetic movements. In the frog Xenopus, extensive embryological and molecular studies have provided major advance in understanding the mechanism implicated in AP patterning. Following fertilization, cortical rotation leads to the transport of maternal determinants to the dorsal region and creates the primary dorsoventral (DV) asymmetry. The activation of maternal Wnt/ß‐catenin signaling and a high Nodal signal induces the formation of the Nieuwkoop center in the dorsal‐vegetal cells, which then triggers the formation of the Spemann organizer in the overlying dorsal marginal zone. It is now well established that the Spemann organizer plays a central role in building the vertebrate body axes because it provides patterning information for both DV and AP polarities. The antagonistic interactions between signals secreted in the Spemann organizer and the opposite ventral region pattern the mesoderm along the DV axis, and this DV information is translated into AP positional values during gastrulation. The formation of anterior neural tissue requires simultaneous inhibition of zygotic Wnt and bone morphogenetic protein (BMP) signals, while an endogenous gradient of Wnt, fibroblast growth factors (FGFs), retinoic acid (RA) signaling, and collinearly expressed Hox genes patterns the trunk and posterior regions. Collectively, DV asymmetry is mostly coupled to AP polarity, and cell–cell interactions mediated essentially by the same regulatory networks operate in DV and AP patterning. WIREs Dev Biol 2016, 5:150–168. doi: 10.1002/wdev.217This article is categorized under:

Early Embryonic Development > Development to the Basic Body Plan
Challenges in carrier‐mediated intracellular delivery: moving beyond endosomal barriers
Authors: Stewart Martin P. , Lorenz Anna , Dahlman James , Sahay Gaurav 
Published: November 2015

The deployment of molecular to microscale carriers for intracellular delivery has tremendous potential for biology and medicine, especially for in vivo therapies. The field remains limited, however, by a poor understanding of how carriers gain access to the cell interior. In this review, we provide an overview of the different types of carriers, their speculated modes of entry, putative pathways of vesicular transport, and sites of endosomal escape. We compare this alongside pertinent examples from the cell biology of how viruses, bacteria, and their effectors enter cells and escape endosomal confinement. We anticipate insights into the mechanisms of cellular entry and endosomal escape will benefit future research efforts on effective carrier‐mediated intracellular delivery. WIREs Nanomed Nanobiotechnol 2016, 8:465–478. doi: 10.1002/wnan.1377This article is categorized under:

Nanotechnology Approaches to Biology > Cells at the Nanoscale
Nanotechnology Approaches to Biology > Nanoscale Systems in Biology
Quality of Life in Thyroid Cancer is Similar to That of Other Cancers with Worse Survival
Authors: Applewhite Megan K. , James Benjamin C. , Kaplan Sharone P. , Angelos Peter , Kaplan Edwin L. , Grogan Raymon H. , Aschebrook‐Kilfoy Briseis 
Published: November 2015

AbstractBackground
The incidence of thyroid cancer is increasing. As such, the number of survivors is rising, and it has been shown that their quality of life (QOL) is worse than expected. Using results from the North American Thyroid Cancer Survivorship Study (NATCSS), a large‐scale survivorship study, we aim to compare the QOL of thyroid cancer survivors to the QOL of survivors of other types of cancer.Methods
The NATCSS assessed QOL overall and in four subcategories: physical, psychological, social, and spiritual well‐being using the QOL‐Cancer Survivor (QOL‐CS) instrument. Studies that used the QOL‐CS to evaluate survivors of other types of cancers were compared to the NATCSS findings using two‐tailed t tests.ResultsWe compared results from NATCSS to QOL survivorship studies in colon, glioma, breast, and gynecologic cancer. The mean overall QOL in NATCSS was 5.56 (on a scale of 0–10, where 10 is the best). Overall QOL of patients with thyroid cancer was similar to that of patients with colon cancer (mean 5.20, p = 0.13), glioma (mean 5.96, p = 0.23), and gynecologic cancer (mean 5.59, p = 0.43). It was worse than patients surveyed with breast cancer (mean 6.51, p < 0.01).ConclusionsWe found the self‐reported QOL of thyroid cancer survivors in our study population is overall similar to or worse than that of survivors of other types of cancer surveyed with the same instrument. This should heighten awareness of the significance of a thyroid cancer diagnosis and highlights the need for further research in how to improve care for this enlarging group of patients.
Associations with Perioperative Mortality Rate at a Major Referral Hospital in Rwanda
Authors: Rickard Jennifer L. , Ntakiyiruta Georges , Chu Kathryn M. 
Published: November 2015

AbstractBackgroundLittle is known about perioperative mortality in sub‐Saharan Africa. The perioperative mortality rate (POMR) and associated factors at a major referral hospital in Rwanda were measured.MethodsThe operative activity at University Teaching Hospital of Kigali was evaluated through an operative database. As a part of this larger study, patient characteristics and outcomes were measured to determine areas for improvement in patient care. Data were collected on patient demographics, surgeon, diagnosis, and operation over a 12‐month period. The primary outcome was POMR. Secondary outcomes were timing and hospital location of death.ResultsThe POMR was 6 %. POMR in patients under 5 years of age was 10 %, 3 % in patients 5–14 years and 6 % in patients age >14 years. For emergency and elective operations, POMR was 9 and 2 %, respectively. POMR was associated with emergency status, congenital anomalies, repeat operations, referral outside Kigali, and female gender. Orthopedic procedures and age 5–14 years were associated with decreased odds of mortality. Forty‐nine percent of deaths occurred in the post‐operative recovery room and 35 % of deaths occurred within the first post‐operative day.ConclusionsThe POMR at a large referral hospital in Rwanda is <10 % demonstrating that surgery can save lives even in resource‐limited settings. Emergency operations are associated with higher mortality, which could potentially be improved with faster identification and transfer from district hospitals. Nearly half of deaths occurred in the post‐operative recovery room. Multidisciplinary audits of operative mortalities could help guide improvements in surgical care.
Hepatic Artery Reconstruction with a Continuous Suture Method for Hepato‐Biliary‐Pancreatic Surgery
Authors: Otsuka Shimpei , Kaneoka Yuji , Maeda Atsuyuki , Takayama Yuichi , Fukami Yasuyuki , Onoe Shunsuke 
Published: November 2015

AbstractBackground
In some cases, hepato‐biliary‐pancreatic (HBP) surgery requires hepatic artery resection and hepatic artery reconstruction (HAR) for histologically curative resection. We describe our surgical HAR technique, which involves continuous suturing, and we report the results of a study of the surgical outcomes.MethodsBetween 2000 and 2014, 380 patients underwent radical surgery for advanced HBP malignancies (118 bile duct cancers, 189 pancreatic head cancers, and 73 gallbladder cancers), 24 of whom (6.3 %) underwent HAR (for complete cure of 16 bile duct cancers, 5 pancreatic cancers, and 3 gallbladder cancers). The 24 surgical procedures included 8 hepato‐pancreatoduodenectomies, 10 hepatectomies, and 6 pancreatoduodenectomies. The ends of the 2 arteries were spatulated, and the reconstruction was performed with a continuous 7‐0 polypropylene suture under loupe magnification.ResultsEighteen right hepatic arteries, 4 left hepatic arteries, and 2 proper hepatic arteries were resected and reconstructed. Median HAR time was 18 min (range 9–31 min). End‐to‐end anastomosis was performed in 7 patients, and heterogeneous reconstruction was performed in 17 patients (with 9 colic arteries, 4 gastroduodenal arteries, and 4 others). Doppler ultrasonography performed upon vessel reconstruction depicted pulsatile flow within the intrahepatic arteries in all cases, and patency of the reconstructed vessel was confirmed postoperatively by contrast‐enhanced CT in 19 patients (82.6 %). Morbidity occurred in 10 patients (42 %), including 4 HAR‐related complications: 3 bile leakages and 1 hepatic abscess.ConclusionOur HAR method can be performed safely and easily by general surgeons. It may be a time‐saving procedure that yields acceptable patency and morbidity rates.
Characteristics of Persistent Hyperparathyroidism After Renal Transplantation
Authors: Yamamoto Takayuki , Tominaga Yoshihiro , Okada Manabu , Hiramitsu Takahisa , Tsujita Makoto , Goto Norihiko , Narumi Shunji , Watarai Yoshihiko 
Published: November 2015

AbstractBackgroundPersistent hyperparathyroidism (HPT) after renal transplantation (RTx), termed tertiary HPT (THPT), is not uncommon. However, risk factors and appropriate operative procedures for THPT are poorly understood.MethodsA retrospective study of patients who underwent RTx without pre‐transplant parathyroidectomy (PTx) was performed at our hospital between January 2001 and March 2011. Risk factors for the development of THPT were investigated by comparing THPT and non‐THPT groups. We retrospectively analyzed patients with THPT who underwent total PTx with forearm autograft. Pre‐ and postoperative (1 year after PTx) laboratory results were analyzed for PTx efficacy.ResultsData for 520 patients were analyzed. On multivariate analysis, long dialysis duration (p = 0.009, hazard ratio (HR) 1.01), large maximum parathyroid gland size before RTx (p = 0.003, HR 1.23), pre‐RTx high intact parathyroid hormone (iPTH) (p = 0.041, HR 1.01), post‐RTx (<2 weeks) high calcium (Ca) (p < 0.001, HR 25.04), and post‐RTx high alkaline phosphatase (ALP) (p = 0.027, HR 0.99) were identified as risk factors for THPT. Patients who underwent PTx showed significant improvement compared with baseline for serum Ca, phosphorus, iPTH, and ALP. Serum creatinine showed no significant difference.ConclusionsSeveral risk factors for THPT development were identified. PTx for patients with THPT significantly improved serum Ca, iPTH, ALP, and phosphorous levels. There was no significant difference in renal function after PTx. Therefore, total PTx with forearm autograft may be an appropriate surgical approach for patients with THPT.
A systematic review of supportive supervision as a strategy to improve primary healthcare services in Sub‐Saharan Africa
Authors: Bailey Claire , Blake Carolyn , Schriver Michael , Cubaka Vincent Kalumire , Thomas Tisa , Martin Hilber Adriane 
Published: November 2015

AbstractBackgroundIt may be assumed that supportive supervision effectively builds capacity, improves the quality of care provided by frontline health workers, and positively impacts clinical outcomes. Evidence on the role of supervision in Sub‐Saharan Africa has been inconclusive, despite the critical need to maximize the workforce in low‐resource settings.ObjectivesTo review the published literature from Sub‐Saharan Africa on the effects of supportive supervision on quality of care, and health worker motivation and performance.Search strategyA systematic review of seven databases of both qualitative and quantitative studies published in peer‐reviewed journals.Selection criteriaSelected studies were based in primary healthcare settings in Sub‐Saharan Africa and present primary data concerning supportive supervision.Data collection and analysisThematic synthesis where data from the identified studies were grouped and interpreted according to prominent themes.Main resultsSupportive supervision can increase job satisfaction and health worker motivation. Evidence is mixed on whether this translates to increased clinical competence and there is little evidence of the effect on clinical outcomes.ConclusionsResults highlight the lack of sound evidence on the effects of supportive supervision owing to limitations in research design and the complexity of evaluating such interventions. The approaches required a high level of external inputs, which challenge the sustainability of such models.