bluuebunny/crossref_metadata_2025_split huggingface dataset:
Long‐term monitoring of tropical alpine habitat change, Andean anurans, and chytrid fungus in the Cordillera Vilcanota, Peru: Results from a decade of study
Authors: Seimon Tracie A. , Seimon Anton , Yager Karina , Reider Kelsey , Delgado Amanda , Sowell Preston , Tupayachi Alfredo , Konecky Bronwen , McAloose Denise , Halloy Stephan 
Published: February 2017

AbstractThe Cordillera Vilcanota in southern Peru is the second largest glacierized range in the tropics and home to one of the largest high‐alpine lakes, Sibinacocha (4,860 m). Here, Telmatobius marmoratus (marbled water frog), Rhinella spinulosa (Andean toad), and Pleurodema marmoratum (marbled four‐eyed frog) have expanded their range vertically within the past century to inhabit newly formed ponds created by ongoing deglaciation. These anuran populations, geographically among the highest (5,200–5,400 m) recorded globally, are being impacted by the chytrid fungus Batrachochytrium dendrobatidis (Bd), and the disease it causes, chytridiomycosis. In this study, we report results from over a decade of monitoring these three anuran species, their habitat, and Bd infection status. Our observations reveal dynamic changes in habitat including ongoing rapid deglaciation (18.4 m/year widening of a corridor between retreating glaciers from 2005 to 2015), new pond formation, changes in vegetation in amphibian habitat, and widespread occurrence of Bd in amphibians in seven sites. Three of these sites have tested positive for Bd over a 9‐ to 12‐year period. In addition, we observed a widespread reduction in T. marmoratus encounters in the Vilcanota in 2008, 2009, and 2012, while encounters increased in 2013 and 2015. Despite the rapid and dynamic changes in habitat under a warming climate, continued presence of Bd in the environment for over a decade, and a reduction in one of three anuran species, we document that these anurans continue to breed and survive in this high Andean environment. High variability in anuran encounters across sites and plasticity in these populations across habitats, sites, and years are all factors that could favor repopulation postdecline. Preserving the connectivity of wetlands in the Cordillera Vilcanota is therefore essential in ensuring that anurans continue to breed and adapt as climate change continues to reshape the environment.
The effect of top‐predator presence and phenotype on aquatic microbial communities
Authors: Sullam Karen E. , Matthews Blake , Aebischer Thierry , Seehausen Ole , Bürgmann Helmut 
Published: February 2017

AbstractThe presence of predators can impact a variety of organisms within the ecosystem, including microorganisms. Because the effects of fish predators and their phenotypic differences on microbial communities have not received much attention, we tested how the presence/absence, genotype, and plasticity of the predatory three‐spine stickleback (Gasterosteus aculeatus) influence aquatic microbes in outdoor mesocosms. We reared lake and stream stickleback genotypes on contrasting food resources to adulthood, and then added them to aquatic mesocosm ecosystems to assess their impact on the planktonic bacterial community. We also investigated whether the effects of fish persisted following the removal of adults, and the subsequent addition of a homogenous juvenile fish population. The presence of adult stickleback increased the number of bacterial OTUs and altered the size structure of the microbial community, whereas their phenotype affected bacterial community composition. Some of these effects were detectable after adult fish were removed from the mesocosms, and after juvenile fish were placed in the tanks, most of these effects disappeared. Our results suggest that fish can have strong short‐term effects on microbial communities that are partially mediated by phenotypic variation of fish.
High‐density lipoprotein‐associated paraoxonase‐1 activity for prediction of adverse outcomes in outpatients with chronic heart failure
Authors: Hammadah Muhammad , Kalogeropoulos Andreas P. , Georgiopoulou Vasiliki V. , Weber Malory , Wu Yuping , Hazen Stanley L. , Butler Javed , Tang W.H. Wilson 
Published: February 2017

AbstractAimsDecreased arylesterase (ArylE) activity of paraoxonase‐1, a HDL‐associated protein with anti‐inflammatory and antioxidant properties, has been associated with increased risk of cardiac events in patients with ischaemic heart failure (HF). We aim to investigate the prognostic significance of changes in serum ArylE activity over time.Methods and resultsWe examined the association between baseline and follow‐up serum ArylE activity and HF outcomes (death, cardiac transplantation, or ventricular assist device implantation) in 299 patients with HF enrolled in a prospective cohort study from January 2008 to July 2009, with 145 patients having available follow‐up levels at 1 year. A significant drop in ArylE activity on follow‐up was defined as a drop of ≥25% vs. baseline levels. Mean baseline and follow‐up ArylE activity levels were 110.6 ± 29.9 µmol/min/mL and 106.2 ± 29.9 µmol/min/mL, respectively. After a mean follow‐up of 2.8 ± 1.1 years, low baseline ArylE activity was associated with increased risk of adverse HF events [hazard ratio (HR; lowest vs highest tertile) 2.6, 95% confidence interval (CI) 1.3–5.5, P = 0.01] and HF‐related hospitalization [incidence rate ratio (lowest vs. highest tertile) 2.1, 95% CI 1.2–4.1, P = 0.016], which remained significant after adjustment for age, male gender, systolic blood pressure, diabetes, creatinine clearance, CAD, and HDL‐cholesterol levels. Patients who had a significant drop in ArylE activity on follow‐up (n = 18) had a significantly increased risk of HF events (HR 4.9, 95% CI 1.6–14.6, P = 0.005), even after adjustment for baseline levels of ArylE activity.ConclusionsReduced baseline ArylE activity and decreased levels on follow‐up are associated with adverse outcomes in stable outpatients with HF.
Measurement of Total Antioxidant Capacity by Electrogenerated Iodine at Disposable Screen Printed Electrodes
Authors: González‐Sánchez María Isabel , Agrisuelas Jerónimo , Valero Edelmira , Compton Richard G. 
Published: February 2017

AbstractTotal antioxidant capacity is an important parameter for the evaluation of the oxidative status in different kinds of biological samples such as plant extracts, or in food industry. We report a fast, easy, portable, cost‐effective electroanalytical method to measure total antioxidant capacity, based on the reaction of natural antioxidants with electrogenerated iodine using disposable platinum screen‐printed electrodes. This reaction can be measured by the increment of the electrochemical current signal of iodide oxidation to iodine during a voltammetric cycle. Iodine reacts with reducing compounds such as glutathione, ascorbate, gallic acid and NADH without interference of the corresponding oxidized counter‐parts. The addition of ascorbate oxidase also allows the concentration of ascorbate to be determined. The method was tested with real samples of plant extracts and the results correlated well with those obtained with a standard spectrophotometric method.
Dispersive liquid–liquid microextraction of quinolones in porcine blood: Validation of a CE method using univariate calibration or multivariate curve resolution‐alternating least squares for overlapped peaks
Authors: Teglia Carla M. , Cámara María S. , Vera‐Candioti Luciana 
Published: February 2017

In the previously published part of this study, we detailed a novel strategy based on dispersive liquid–liquid microextraction to extract and preconcentrate nine fluoroquinolones in porcine blood. Moreover, we presented the optimized experimental conditions to obtain complete CE separation between target analytes. Consequently, this second part reports the validation of the developed method to determine flumenique, difloxacin, enrofloxacin, marbofloxacin, ofloxacin, ciprofloxacin, through univariate calibration, and enoxacin, danofloxacin, and gatifloxacin through multivariate curve resolution analysis. The validation was performed according to FDA guidelines for bioanalytical assay procedures and the European Directive 2002/657 to demonstrate that the results are reliable. The method was applied for the determination of fluoroquinolones in real samples. Results indicated a high selectivity and excellent precision characteristics, with RSD less than 11.9% in the concentrations, in intra‐ and interassay precision studies. Linearity was proved for a range from 4.00 to 30.00 mg/L and the recovery has been investigated at four different fortification levels, from 89 to 113%. Several approaches found in the literature were used to determinate the LODs and LOQs. Though all strategies used were appropriate, we obtained different values when using different methods. Estimating the S/N ratio with the mean noise level in the migration time of each fluoroquinolones turned out as the best studied method for evaluating the LODs and LOQs, and the values were in a range of 1.55 to 4.55 mg/L and 5.17 to 9.62 mg/L, respectively.
The use of 3D modeling for the prediction of the seismic demands on the gravity dams
Authors: Bybordiani M. , Arıcı Y. 
Published: February 2017

SummarySeismic behavior of gravity dams has long been evaluated using a representative two‐dimensional (2D) system. Formulated for the gravity dams built in wide canyons, the assumption is nevertheless utilized extensively for almost all concrete dams due to the established procedures as well as the expected computational costs of a three‐dimensional model. However, a significant number of roller‐compacted concrete dams, characterized as such systems, do not conform to the basic assumptions of these methods by violating the conditions on canyon dimensions and joint‐spacing/details. Based on the premise that the 2D modeling assumption is overstretched for practical purposes in a variety of settings, the purpose of this study is to critically evaluate the use of 2D modeling for the prediction of the seismic demands on these systems. Using a rigorous soil–structure interaction approach, the difference between the two and three‐dimensional response for gravity dams was investigated first in the frequency domain for a range of canyon widths and foundation to dam moduli ratios. Then, the time domain differences between the crest displacements and the maximum principal stress were obtained using 70 different ground motions in order to show the possible bias introduced into the analysis results due to the modeling approach. The results of the study show that even for relatively wide canyons, the 2D analysis can lead to misleading predictions. Copyright © 2017 John Wiley & Sons, Ltd.
A scientific theory of Ars Memoriae: Spatial view cells in a continuous attractor network with linked items
Authors: Rolls Edmund T. 
Published: February 2017

ABSTRACTThe art of memory (ars memoriae) used since classical times includes using a well‐known scene to associate each view or part of the scene with a different item in a speech. This memory technique is also known as the “method of loci.” The new theory is proposed that this type of memory is implemented in the CA3 region of the hippocampus where there are spatial view cells in primates that allow a particular view to be associated with a particular object in an event or episodic memory. Given that the CA3 cells with their extensive recurrent collateral system connecting different CA3 cells, and associative synaptic modifiability, form an autoassociation or attractor network, the spatial view cells with their approximately Gaussian view fields become linked in a continuous attractor network. As the view space is traversed continuously (e.g., by self‐motion or imagined self‐motion across the scene), the views are therefore successively recalled in the correct order, with no view missing, and with low interference between the items to be recalled. Given that each spatial view has been associated with a different discrete item, the items are recalled in the correct order, with none missing. This is the first neuroscience theory of ars memoriae. The theory provides a foundation for understanding how a key feature of ars memoriae, the ability to use a spatial scene to encode a sequence of items to be remembered, is implemented. © 2017 Wiley Periodicals, Inc.
Feasibility of using pessaries for treatment of pelvic organ prolapse in rural Nepal
Authors: Robert Magali , Govan A. Jane , Lohani Uma , Uprety Aruna 
Published: February 2017

AbstractObjectiveTo evaluate the acceptability, feasibility, and outcomes of pessary fitting in rural Nepali communities.MethodsA 1‐year prospective cohort study was conducted in the Ramechhap district of Nepal in January 2013–January 2014 among women attending a free gynecology health camp. All women with symptomatic pelvic organ prolapse (POP) were offered ring pessaries. Demographic information was collected and questionnaires on POP were completed. A urogynecologic examination was performed. At the 1‐year follow‐up, women were questioned on pessary use and underwent an examination. Logistic regression was used to identify associations.ResultsIn total, 411 women attended the health camps, of whom 142 presented with symptomatic POP. Initial fitting was accomplished for 134 (94.4%) of the women. At the 1‐year follow‐up, 130 (97.0%) women in the cohort were evaluated, and 72 (55.4%) were still using the pessary. The primary reason for discontinuation was the pessary falling out (35/58, 60.3%). The most common complication was vaginal erosion (18/130, 13.8%), observed exclusively among postmenopausal women. Postmenopausal status was a predictor of continued use (odds ratio 3.12, 95% confidence interval 1.45–6.72; P=0.004).ConclusionPessaries were found to be an acceptable and feasible option with minimal complications for treating POP in rural Nepal.
Continuous microfluidic assembly of biodegradable poly(beta‐amino ester)/DNA nanoparticles for enhanced gene delivery
Authors: Wilson David R. , Mosenia Arman , Suprenant Mark P. , Upadhya Rahul , Routkevitch Denis , Meyer Randall A. , Quinones‐Hinojosa Alfredo , Green Jordan J. 
Published: February 2017

AbstractTranslation of biomaterial‐based nanoparticle formulations to the clinic faces significant challenges including efficacy, safety, consistency and scale‐up of manufacturing, and stability during long‐term storage. Continuous microfluidic fabrication of polymeric nanoparticles has the potential to alleviate the challenges associated with manufacture, while offering a scalable solution for clinical level production. Poly(beta‐amino esters) (PBAE)s are a class of biodegradable cationic polymers that self‐assemble with anionic plasmid DNA to form polyplex nanoparticles that have been shown to be effective for transfecting cancer cells specifically in vitro and in vivo. Here, we demonstrate the use of a microfluidic device for the continuous and scalable production of PBAE/DNA nanoparticles followed by lyophilization and long term storage that results in improved in vitro efficacy in multiple cancer cell lines compared to nanoparticles produced by bulk mixing as well as in comparison to widely used commercially available transfection reagents polyethylenimine and Lipofectamine® 2000. We further characterized the nanoparticles using nanoparticle tracking analysis (NTA) to show that microfluidic mixing resulted in fewer DNA‐free polymeric nanoparticles compared to those produced by bulk mixing. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 1813–1825, 2017.
Coupling of Bone Resorption and Formation in Real Time: New Knowledge Gained From Human Haversian BMUs
Authors: Lassen Nicolai Ernlund , Andersen Thomas Levin , Pløen Gro Grunnet , Søe Kent , Hauge Ellen Margrethe , Harving Søren , Eschen Gete Ester Toft , Delaisse Jean-Marie 
Published: February 2017

ABSTRACT

It is well known that bone remodeling starts with a resorption event and ends with bone formation. However, what happens in between and how resorption and formation are coupled remains mostly unknown. Remodeling is achieved by so-called basic multicellular units (BMUs), which are local teams of osteoclasts, osteoblasts, and reversal cells recently proven identical with osteoprogenitors. Their organization within a BMU cannot be appropriately analyzed in common histology. The originality of the present study is to capture the events ranging from initiation of resorption to onset of formation as a functional continuum. It was based on the position of specific cell markers in longitudinal sections of Haversian BMUs generating new canals through human long bones. It showed that initial resorption at the tip of the canal is followed by a period where newly recruited reversal/osteoprogenitor cells and osteoclasts alternate, thus revealing the existence of a mixed “reversal-resorption” phase. Three-dimensional reconstructions obtained from serial sections indicated that initial resorption is mainly involved in elongating the canal and the additional resorption events in widening it. Canal diameter measurements show that the latter contribute the most to overall resorption. Of note, the density of osteoprogenitors continuously grew along the “reversal/resorption” surface, reaching at least 39 cells/mm on initiation of bone formation. This value was independent of the length of the reversal/resorption surface. These observations strongly suggest that bone formation is initiated only above a threshold cell density, that the length of the reversal/resorption period depends on how fast osteoprogenitor recruitment reaches this threshold, and thus that the slower the rate of osteoprogenitor recruitment, the more bone is degraded. They lead to a model where the newly recognized reversal/resorption phase plays a central role in the mechanism linking osteoprogenitor recruitment and the resorption-formation switch. © 2017 American Society for Bone and Mineral Research.
VDR in Osteoblast‐Lineage Cells Primarily Mediates Vitamin D Treatment‐Induced Increase in Bone Mass by Suppressing Bone Resorption
Authors: Nakamichi Yuko , Udagawa Nobuyuki , Horibe Kanji , Mizoguchi Toshihide , Yamamoto Yoko , Nakamura Takashi , Hosoya Akihiro , Kato Shigeaki , Suda Tatsuo , Takahashi Naoyuki 
Published: February 2017

ABSTRACTLong‐term treatment with active vitamin D [1α,25(OH)2D3] and its derivatives is effective for increasing bone mass in patients with primary and secondary osteoporosis. Derivatives of 1α,25(OH)2D3, including eldecalcitol (ELD), exert their actions through the vitamin D receptor (VDR). ELD is more resistant to metabolic degradation than 1α,25(OH)2D3. It is reported that ELD treatment causes a net increase in bone mass by suppressing bone resorption rather than by increasing bone formation in animals and humans. VDR in bone and extraskeletal tissues regulates bone mass and secretion of osteotropic hormones. Therefore, it is unclear what types of cells expressing VDR preferentially regulate the vitamin D–induced increase in bone mass. Here, we examined the effects of 4‐week treatment with ELD (50 ng/kg/day) on bone using osteoblast lineage‐specific VDR conditional knockout (Ob‐VDR‐cKO) and osteoclast‐specific VDR cKO (Ocl‐VDR‐cKO) male mice aged 10 weeks. Immunohistochemically, VDR in bone was detected preferentially in osteoblasts and osteocytes. Ob‐VDR‐cKO mice showed normal bone phenotypes, despite no appreciable immunostaining of VDR in bone. Ob‐VDR‐cKO mice failed to increase bone mass in response to ELD treatment. Ocl‐VDR‐cKO mice also exhibited normal bone phenotypes, but normally responded to ELD. ELD‐induced FGF23 production in bone was regulated by VDR in osteoblast‐lineage cells. These findings suggest that the vitamin D treatment‐induced increase in bone mass is mediated by suppressing bone resorption through VDR in osteoblast‐lineage cells. © 2017 The Authors. Journal of Bone and Mineral Research Published by Wiley Periodicals Inc.
Identifying relations between imaging phenotypes and molecular subtypes of breast cancer: Model discovery and external validation
Authors: Wu Jia , Sun Xiaoli , Wang Jeff , Cui Yi , Kato Fumi , Shirato Hiroki , Ikeda Debra M. , Li Ruijiang 
Published: February 2017

PurposeTo determine whether dynamic contrast enhancement magnetic resonance imaging (DCE‐MRI) characteristics of the breast tumor and background parenchyma can distinguish molecular subtypes (ie, luminal A/B or basal) of breast cancer.Materials and MethodsIn all, 84 patients from one institution and 126 patients from The Cancer Genome Atlas (TCGA) were used for discovery and external validation, respectively. Thirty‐five quantitative image features were extracted from DCE‐MRI (1.5 or 3T) including morphology, texture, and volumetric features, which capture both tumor and background parenchymal enhancement (BPE) characteristics. Multiple testing was corrected using the Benjamini–Hochberg method to control the false‐discovery rate (FDR). Sparse logistic regression models were built using the discovery cohort to distinguish each of the three studied molecular subtypes versus the rest, and the models were evaluated in the validation cohort.ResultsOn univariate analysis in discovery and validation cohorts, two features characterizing tumor and two characterizing BPE were statistically significant in separating luminal A versus nonluminal A cancers; two features characterizing tumor were statistically significant for separating luminal B; one feature characterizing tumor and one characterizing BPE reached statistical significance for distinguishing basal (WilcoxonP< 0.05, FDR < 0.25). In discovery and validation cohorts, multivariate logistic regression models achieved an area under the receiver operator characteristic curve (AUC) of 0.71 and 0.73 for luminal A cancer, 0.67 and 0.69 for luminal B cancer, and 0.66 and 0.79 for basal cancer, respectively.ConclusionDCE‐MRI characteristics of breast cancer and BPE may potentially be used to distinguish among molecular subtypes of breast cancer.Level of Evidence:3Technical Efficacy:Stage 3J. Magn. Reson. Imaging 2017;46:1017–1027.
Cytokine Interferon‐γ suppresses the function of capsule myofibroblasts and induces cell apoptosis
Authors: Mattyasovszky Stefan G. , Mausbach Stefan , Ritz Ulrike , Wollstädter Jochen , Schmidtmann Irene , Baranowski Andreas , Drees Phillipp , Rommens Pol M. , Hofmann Alexander 
Published: February 2017

ABSTRACTMyofibroblasts (MFs), a contractile subset of fibroblasts, play a pivotal role in physiological wound healing and in the development of many fibroconnective disorders. The complex cytokine network regulating the function of MFs in joint stiffness is still poorly understood. In this in vitro study, we investigated the effect of the cytokine Interferon‐gamma (IFN‐γ) on MFs isolated from human joint capsules. MFs were cultivated either in the presence of increasing concentrations of IFN‐γ alone or in combination with IFN‐γ neutralizing antibodies. Cell viability, cytotoxicity, apoptosis, and mRNA gene expression of the MF markers alpha‐smooth muscle actin (α‐SMA) and collagen type I were analyzed in MF cultures. Contraction potential was analyzed in an established collagen gel contraction assay simulating the extracellular matrix. Using immunofluorescence staining, we could verify that MFs express IFN‐γ‐receptor (R)‐1 on their membrane. IFN‐γ decreased MF viability and significantly elevated the apoptosis rate in a dose‐dependent manner. IFN‐γ down‐regulated α‐SMA and collagen type I mRNA expression which was associated with a diminished MF mediated contraction of the gel matrices. These effects were suppressed by simultaneous treatment of cells with a neutralizing IFN‐γ antibody. Our experiments confirm the hypothesis that the cytokine IFN‐γ is a crucial component of the regulatory network of capsule MFs. IFN‐γ notably influences the ability of MFs to contract collagen matrices by suppressing α‐SMA gene expression. IFN‐γ is toxic for MFs in high concentrations and may negatively regulate the number of pro‐fibrotic MFs during the healing process via induction of cell apoptosis. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:2524–2533, 2017.