bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dominant hemisphere functional networks compensate for structural connectivity loss to preserve phonological retrieval with aging
Authors: Agarwal Smriti , Stamatakis Emmanuel A. , Geva Sharon , Warburton Elizabeth A. 
Published: July 2016

AbstractIntroductionLoss of hemispheric asymmetry during cognitive tasks has been previously demonstrated in the literature. In the context of language, increased right hemisphere activation is observed with aging. Whether this relates to compensation to preserve cognitive function or dedifferentiation implying loss of hemispheric specificity without functional consequence, remains unclear.MethodsWith a multifaceted approach, integrating structural and functional imaging data during a word retrieval task, in a group of younger and older adults with equivalent cognitive performance, we aimed to establish whether interactions between hemispheres or reorganization of dominant hemisphere networks preserve function. We examined functional and structural connectivity on data from our previously published functional activation study. Functional connectivity was measured using psychophysiological interactions analysis from the left inferior frontal gyrus (LIFG) and the left insula (LINS), based on published literature, and the right inferior frontal gyrus (RIFG) based on our previous study.ResultsAlthough RIFG showed increased activation, its connectivity decreased with age. Meanwhile, LIFG and LINS connected more bilaterally in the older adults. White matter integrity, measured by fractional anisotropy (FA) from diffusion tensor imaging, decreased significantly in the older group. Importantly, LINS functional connectivity to LIFG correlated inversely with FA.ConclusionsWe demonstrate that left hemispheric language areas show higher functional connectivity in older adults with intact behavioral performance, and thus, may have a role in preserving function. The inverse correlation of functional and structural connectivity with age is in keeping with emerging literature and merits further investigation with tractography studies and in other cognitive domains.
miR‐302b regulates cell cycles by targeting CDK2 via ERK signaling pathway in gastric cancer
Authors: Liu Fu‐Yun , Wang Li‐Ping , Wang Qin , Han Ping , Zhuang Wen‐Ping , Li Mu‐Juan , Yuan Hua 
Published: July 2016

AbstractTo investigate the molecular mechanism of miR‐302b in the regulation of cell proliferation and cell cycle regulation in gastric cancer. Samples of tumor and adjacent normal tissues were collected from 30 gastric cancer patients. Bioinformatics and the dual luciferase report were used for verification of the relationship between miR‐302b expression and cyclin‐dependent kinase 2 (CDK2). RT‐PCR and western blot were used to examine CDK2 mRNA and protein levels. The impacts of miR‐302b on CDK2 expression and extracellular signal‐regulated kinase (ERK) signaling pathway were assessed in cells transfected with miR‐302b analogs and CDK2 overexpression carrier, respectively. We used 3‐(4,5‐dimethylthiazol‐2‐yl)‐2, 5‐diphenyltetrazolium bromide (MTT) to assay gastric cancer cell growth after transfection, flow cytometry to analyze cell cycle. Compared with normal tissues, miR‐302b expression was significantly lower in gastric cancer tissues, which was significantly related to lymph node metastasis, metastasis distance, and TNM staging. miR‐302b expression was increased in miR‐302b mimics transfected cells and was significantly decreased in miR‐302b inhibitors transfected cells. CDK2 is a target gene of miR‐302b. Decreased miR‐302b and increased CDK2 expressions can significantly promote proliferation and G1/S phase transformation in gastric cancer. miR‐302b promoted the proliferation of gastric cancer cells through upregulation of CDK2, thereby inhibiting ERK pathway, which can in turn inhibit the promoting ability of miR‐302b on proliferation. The upregulation of miR‐302b reduced the expression of CDK2, and inhibited ERK signaling pathway, thereby inhibiting cell proliferation and G1/S phase conversion rate. Therefore, miR‐302b provides new perspectives for research of cell regulation and proliferation in gastric cancer, and new targets for gastric cancer diagnosis and treatment.
Angiographic severity does not correlate with fractional flow reserve in heavily calcified coronary arteries
Authors: Johnson Paul M. , Madamanchi Chaitanya , Sharalaya Zarina M. , Iqbal Zahra , Gehi Anil K. , Kaul Prashant , Stouffer George A. 
Published: July 2016

ObjectivesTo determine the relationship between severity of stenosis and hemodynamic significance in calcified coronary arteries.BackgroundSeverity of stenosis is widely used to determine the need for revascularization but the effect of lesion calcification on hemodynamic significance is not well understood.MethodsTwo hundred consecutive patients undergoing fractional flow reserve (FFR) testing of an intermediate coronary lesion with a pressure wire and intravenous infusion of adenosine were studied. Coronary calcium was quantified based upon radiopacities at the site of the stenosis on cineangiography using the method of Mintz et al. (0 = none or mild calcium, 1 = moderate calcium, 2 = severe calcium).ResultsMean age was 61 ± 11 years, 66% were males, 87.5% had hypertension, 44.5% had diabetes, and 20.5% were current smokers. The mean coronary stenosis by quantitative coronary angiography was 60 ± 12% and the mean FFR was 0.83 ± 0.08. There were 109, 45, and 46 patients classified as Calcium Score of 0, 1, or 2, respectively. Compared to those with no/mild or moderate calcification, patients with severe coronary calcium were older and more likely to have chronic kidney disease and pulmonary disease. The correlation between angiographic severity and FFR decreased as lesion calcification increased [calcium score = 0 (R2 = 0.25, P < 0.005); calcium score = 1 (R2 = 0.11, P < 0.005); calcium score = 2 (R2 = 0.02, P = 0.35)].ConclusionsIn patients with heavily calcified coronary lesions, there was no association between angiographic stenosis and hemodynamic significance and FFR is needed to determine hemodynamic significance of intermediate lesions. © 2016 Wiley Periodicals, Inc.
Optic nerve astrocytoma in a dog
Authors: Rozov Orr , Piñeyro Pablo E. , Zimmerman Kurt L. , Herring Ian P. , Matusow Rachel , Rossmeisl John H. , Jortner Bernard S. , Dreyfus Jennifer 
Published: July 2016

Key Clinical MessageIntracranial astrocytomas are relatively uncommon in dogs and optic nerve astrocytomas even more so. This neoplasm should be considered as differential in canine patients with vision loss, retinal detachment, ocular mass, and histopathologic findings of infiltrative fusiform to polygonal glial cells possibly associated with glomeruloid vascular proliferation.
Catalytic Hydroxylation of Benzene to Phenol by Dioxygen with an NADH Analogue
Authors: Hirose Kensaku , Ohkubo Kei , Fukuzumi Shunichi 
Published: July 2016

AbstractHydroxylation of benzene by molecular oxygen (O2) occurs efficiently with 10‐methyl‐9,10‐dihydroacridine (AcrH2) as an NADH analogue in the presence of a catalytic amount of Fe(ClO4)3 or Fe(ClO4)2 with excess trifluoroacetic acid in a solvent mixture of benzene and acetonitrile (1:1 v/v) to produce phenol, 10‐methylacridinium ion and hydrogen peroxide (H2O2) at 298 K. The catalytic oxidation of benzene by O2 with AcrH2 in the presence of a catalytic amount of Fe(ClO4)3 is started by the formation of H2O2 from AcrH2, O2, and H+. Hydroperoxyl radical (HO2.) is produced from H2O2 with the redox pair of Fe3+/Fe2+ by a Fenton type reaction. The rate‐determining step in the initiation is the proton‐coupled electron transfer from Fe2+ to H2O2 to produce HO. and H2O. HO. abstracts hydrogen rapidly from H2O2 to produce HO2. and H2O. The Fe3+ produced was reduced back to Fe2+ by H2O2. HO2. reacts with benzene to produce the radical adduct, which abstracts hydrogen from AcrH2 to give the corresponding hydroperoxide, accompanied by generation of acridinyl radical (AcrH.) to constitute the radical chain reaction. Hydroperoxyl radical (HO2.), which was detected by using the spin trap method with EPR analysis, acts as a chain carrier for the two radical chain pathways: one is the benzene hydroxylation with O2 and the second is oxidation of an NADH analogue with O2 to produce H2O2.
2‐Anilino‐3‐Aroylquinolines as Potent Tubulin Polymerization Inhibitors
Authors: Srikanth P. S. , Nayak V. Lakshma , Suresh Babu Korrapati , Kumar G. Bharath , Ravikumar A. , Kamal Ahmed 
Published: July 2016

AbstractSeveral 2‐anilino‐3‐aroylquinolines were designed, synthesized, and screened for their cytotoxic activity against five human cancer cell lines: HeLa, DU‐145, A549, MDA‐MB‐231, and MCF‐7. Their IC50 values ranged from 0.77 to 23.6 μm. Among the series, compounds 7 f [(4‐fluorophenyl)(2‐((4‐fluorophenyl)amino)quinolin‐3‐yl)methanone] and 7 g [(4‐chlorophenyl)(2‐((4‐fluorophenyl)amino)quinolin‐3‐yl)methanone] showed remarkable antiproliferative activity against human lung cancer and prostate cancer cell lines. The IC50 values for inhibiting tubulin polymerization were 2.24 and 2.10 μm for compounds 7 f and 7 g, respectively, and were much lower than that of the reference compound E7010 [N‐(2‐(4‐hydroxyphenylamino)pyridin‐3‐yl)‐4‐methoxybenzenesulfonamide]. Furthermore, flow cytometric analysis revealed that these compounds arrest the cell cycle at the G2/M phase, leading to apoptosis. Apoptosis was also confirmed by mitochondrial membrane potential, Annexin V–FITC assay, and intracellular ROS generation. Immunohistochemistry, western blot, and tubulin polymerization assays showed that these compounds disrupt tubulin polymerization. Molecular docking studies revealed that these compounds bind efficiently to β‐tubulin at the colchicine binding site.
Homogeneous Catalyzed Reactions of Levulinic Acid: To γ‐Valerolactone and Beyond
Authors: Omoruyi Uwaila , Page Samuel , Hallett Jason , Miller Philip W. 
Published: July 2016

AbstractPlatform chemicals derived from lignocellulosic plant biomass are viewed as a sustainable replacement for crude oil‐based feedstocks. Levulinic acid (LA) is one such biomass‐derived chemical that has been widely studied for further catalytic transformation to γ‐valerolactone (GVL), an important ‘green’ fuel additive, solvent, and fine chemical intermediate. Although the transformation of LA to GVL can be achieved using heterogeneous catalysis, homogeneous catalytic systems that operate under milder reactions, give higher selectivities and can be recycled continuously are attracting considerable attention. A range of new homogeneous catalysts have now been demonstrated to efficiently convert LA to GVL and to transform LA directly to other value‐added chemicals such as 1,4‐pentanediol (1,4‐PDO) and 2‐methyltetrahydrofuran (2‐MTHF). This Minireview covers recent advances in the area of homogeneous catalysis for the conversion of levulinic acid and levulinic ester derivatives to GVL and chemicals beyond GVL.
Fine‐needle aspiration of cervical lymph nodes yields adequate materials for accurate HPV testing in metastatic head and neck squamous cell carcinomas
Authors: Hou Yanjun , Chaudhary Shweta , Shen Rulong , Li Zaibo 
Published: July 2016

BackgroundHigh‐risk Human papillomavirus (HR‐HPV)‐associated head and neck squamous cell carcinoma (HNSCC) is a distinct epidemiologic and pathologic disease. The data of HR‐HPV testing on fine‐needle aspiration (FNA) materials of cervical lymph nodes in patients with metastatic HNSCC are limited.MethodsWe retrospectively reviewed metastatic HNSCC cases with cervical lymph node FNAs which were tested for p16 immunohistochemistry (IHC) and HR‐HPV DNA in situ hybridization (ISH).ResultsOf the 87 cases studied, the overall adequacy rate of cell block material was 86% for HR‐HPV ISH, 93% for p16 IHC, 84% for both and 95% for either one. Pathologist‐performed FNAs showed significantly higher percentage of satisfactory specimens for p16 and HR‐HPV tests than clinician‐performed FNAs. Of the 73 cases adequate for both p16 IHC and HR‐HPV ISH, the concordant rate between p16 and HR‐HPV results was 78%. P16 positivity had sensitivity of 90% and specificity of 75% to predict primary oropharyngeal HNSCC, while HR‐HPV test showed a similar high sensitivity (91%) but a better specificity (94%).ConclusionFNAs of cervical lymph nodes yield adequate materials for reliable HR‐HPV testing in metastatic HNSCCs and should be incorporated into routine pathologic evaluation for these patients. The high concordance between p16 IHC and HR‐HPV ISH suggests p16 IHC may serve as a surrogate for HR‐HPV ISH in metastatic HNSCC cases with oropharyngeal origin and is helpful to pinpoint primary tumor site. Diagn. Cytopathol. 2016;44:792–798. © 2016 Wiley Periodicals, Inc.
Robust calling performance in frogs infected by a deadly fungal pathogen
Authors: Greenspan Sasha E. , Roznik Elizabeth A. , Schwarzkopf Lin , Alford Ross A. , Pike David A. 
Published: July 2016

AbstractReproduction is an energetically costly behavior for many organisms, including species with mating systems in which males call to attract females. In these species, calling males can often attract more females by displaying more often, with higher intensity, or at certain frequencies. Male frogs attract females almost exclusively by calling, and we know little about how pathogens, including the globally devastating fungus, Batrachochytrium dendrobatidis, influence calling effort and call traits. A previous study demonstrated that the nightly probability of calling by male treefrogs, Litoria rheocola, is elevated when they are in good body condition and are infected by B. dendrobatidis. This suggests that infections may cause males to increase their present investment in mate attraction to compensate for potential decreases in future reproduction. However, if infection by B. dendrobatidis decreases the attractiveness of their calls, infected males might experience decreased reproductive success despite increases in calling effort. We examined whether calls emitted by L. rheocola infected by B. dendrobatidis differed from those of uninfected individuals in duration, pulse rate, dominant frequency, call rate, or intercall interval, the attributes commonly linked to mate choice. We found no effects of fungal infection status or infection intensity on any call attribute. Our results indicate that infected males produce calls similar in all the qualities we measured to those of uninfected males. It is therefore likely that the calls of infected and uninfected males should be equally attractive to females. The increased nightly probability of calling previously demonstrated for infected males in good condition may therefore lead to greater reproductive success than that of uninfected males. This could reduce the effectiveness of natural selection for resistance to infection, but could increase the effectiveness of selection for infection tolerance, the ability to limit the harm caused by infection, such as reductions in body condition.
Mapping and understanding dry season soil water drawdown by California montane vegetation
Authors: Fellows A. W. , Goulden M. L. 
Published: July 2016

AbstractThe ability of soil to supply plant available water during dry periods is a poorly understood but critically important ecosystem property that affects vegetation health and regional hydrology. We estimated and analyzed the cumulative dry season drawdown of soil water across montane California using a spatially resolved water balance model that combined field, meteorological, and remote sensing observations. Dry season soil water drawdown varied markedly with elevation, increasing from <200 mm/yr below 500 m, to ~425 mm/yr at 1000 to 2000 m, before decreasing to <200 mm/yr above ~3000 m. Soil water drawdown was comparatively low at drier (mean annual precipitation < 1000 mm/yr) or colder (mean annual temperature < 4°C) locations; soil water drawdown was greater at wetter and warmer locations, including conifer forests. The reduced soil water drawdown at low‐elevation dry locations may reflect inadequate precipitation to recharge the soil; the reduced water drawdown at high, cold locations presumably reflects limited storage capacity or sparse vegetation development. Soil water drawdown was reduced at locations that were glaciated during the Pleistocene and was only weakly related to rock type. The amount of soil water drawdown implies that many California ecosystems are deeply rooted, with conifer forest rooting to at least 3.6 m. Deep rooting allows many California ecosystems to limit current summer moisture limitation and suggests some of these ecosystems may be able to also limit future increased moisture stress with climate warming if they are able to support increased evaporative demand by further tapping belowground moisture.
The genetic Allee effect: a unified framework for the genetics and demography of small populations
Authors: Luque Gloria M. , Vayssade Chloé , Facon Benoît , Guillemaud Thomas , Courchamp Franck , Fauvergue Xavier 
Published: July 2016

AbstractThe Allee effect is a theoretical model predicting low growth rates and the possible extinction of small populations. Historically, studies of the Allee effect have focused on demography. As a result, underlying processes other than the direct effect of population density on fitness components are not generally taken into account. There has been heated debate about the potential of genetic processes to drive small populations to extinction, but recent studies have shown that such processes clearly impact small populations over short time scales, and some may generate Allee effects. However, as opposed to the ecological Allee effect, which is underpinned by cooperative interactions between individuals, genetically driven Allee effects require a change in genetic structure to link the decline in population size with a decrease in fitness components. We therefore define the genetic Allee effect as a two‐step process whereby a decrease in population size leads to a change in population genetic structure and, in turn, to a decrease in individual fitness. We describe potential underlying mechanisms and review the evidence for this original type of component Allee effect, using published examples from both plants and animals. The possibility of considering demogenetic feedback in light of genetic Allee effects clarifies the analysis and interpretation of demographic and genetic processes, and the interplay between them, in small populations.
Silica uptake and release in live and decaying biomass in a northern hardwood forest
Authors: Clymans Wim , Conley Daniel J. , Battles John J. , Frings Patrick J. , Koppers Mary Margaret , Likens Gene E. , Johnson Chris E. 
Published: July 2016

AbstractIn terrestrial ecosystems, a large portion (20–80%) of the dissolved Si (DSi) in soil solution has passed through vegetation. While the importance of this “terrestrial Si filter” is generally accepted, few data exist on the pools and fluxes of Si in forest vegetation and the rate of release of Si from decomposing plant tissues. We quantified the pools and fluxes of Si through vegetation and coarse woody debris (CWD) in a northern hardwood forest ecosystem (Watershed 6, W6) at the Hubbard Brook Experimental Forest (HBEF) in New Hampshire,USA. Previous work suggested that the decomposition ofCWDmay have significantly contributed to an excess ofDSi reported in stream‐waters following experimental deforestation of Watershed 2 (W2) at theHBEF. We found that woody biomass (wood + bark) and foliage account for approximately 65% and 31%, respectively, of the total Si in biomass at theHBEF. During the decay of American beech (Fagus grandifolia) boles, Si loss tracked the whole‐bole mass loss, while yellow birch (Betula alleghaniensis) and sugar maple (Acer saccharum) decomposition resulted in a preferential Si retention of up to 30% after 16 yr. A power‐law model for the changes in wood and bark Si concentrations during decomposition, in combination with an exponential model for whole‐bole mass loss, successfully reproduced Si dynamics in decaying boles. Our data suggest that a minimum of 50% of theDSi annually produced in the soil of a biogeochemical reference watershed (W6) derives from biogenic Si (BSi) dissolution. The major source is fresh litter, whereas only ~2% comes from the decay ofCWD. Decay of tree boles could only account for 9% of the excessDSi release observed following the experimental deforestation of W2. Therefore, elevatedDSi concentrations after forest disturbance are largely derived from other sources (e.g., dissolution ofBSi from forest floor soils and/or mineral weathering).
Contacts with large, active individuals intensify the predation risk of small conspecifics
Authors: Yamaguchi Aya , Takatsu Kunio , Kishida Osamu 
Published: July 2016

AbstractSize variation within a population can influence the structure of ecosystem interactions, because ecological performance differs between individuals of different sizes. Although the impact of size variation in a predator species on the structure of interactions is well understood, our knowledge about how size variation in a prey species might modify the interactions between predators and prey is very limited. Here, by examining the interactions between predatory Hynobius retardatus salamander larvae and their prey, Rana pirica frog tadpoles, we investigated how large prey individuals affect the predation mortality of small prey conspecifics. First, in an experiment conducted in a field pond in which we manipulated the presence of salamanders and large tadpoles (i.e., large enough to protect them against salamander predation) with small tadpoles, we showed that in the presence of large tadpoles the mortality of small tadpoles from salamander predation was increased. On the basis of our observations of the activity of individuals, we hypothesized that active large tadpoles caused physical disturbances, which in turn caused the small tadpoles to move, and thus increased their encounter frequency with the predatory salamanders. To test this hypothesis, we conducted a laboratory experiment in small tanks with three players (i.e., one salamander as predator, one small tadpole as focal prey, and either a small or a large tadpole as the prospective movement inducer). In each tank, we manipulated the presence or absence of a movement inducer, and, when present, its size (large or small) and access (caged or uncaged) to the focal prey. In the presence of a large, uncaged movement inducer, the focal prey was more active and suffered from higher predation mortality compared with the other treatments, because the large movement inducer (unlike a small movement inducer) moved actively and, when uncaged, could stimulate movement of the focal prey through direct contact. The results indicated that high activity of large prey individuals and the resulting behavioral interactions with small conspecifics via direct contact indirectly increased the mortality of the small prey.