bluuebunny/crossref_metadata_2025_split huggingface dataset:
Regime shifts shorten food chains for mesopredators with potential sublethal effects
Authors: Hempson Tessa N. , Graham Nicholas A. J. , MacNeil M. Aaron , Bodin Nathalie , Wilson Shaun K. 
Published: November 2017

Abstract

Predator populations are in decline globally. Exploitation, as well as habitat degradation and associated changes in prey availability are key drivers of this process of trophic downgrading. In the short term, longevity and dietary adaptability of large‐bodied consumers can mask potential sublethal effects of a changing prey base, producing a delayed effect that may be difficult to detect.

In coral reef ecosystems, regime shifts from coral‐ to algae‐dominated states caused by coral bleaching significantly alter the assemblage of small‐bodied reef fish associated with a reef. The effects of this changing prey community on reef‐associated mesopredators remains poorly understood.

This study found that the total diversity, abundance and biomass of piscivorous mesopredators was lower on regime‐shifted reefs than recovering reefs, 16 years after the 1998 mass coral bleaching event.

We used stable isotope analyses to test for habitat‐driven changes in the trophic niche occupied by a key piscivorous fishery target species on reefs that had regime‐shifted or recovered following climatic disturbance. Using morphometric indices, histology, and lipid analyses, we also investigated whether there were sublethal costs for fish on regime‐shifted reefs.

Stable isotopes demonstrated that fish from regime‐shifted reefs fed further down the food chain, compared to recovering reefs. Lower densities of hepatocyte vacuoles in fish from regime‐shifted reefs, and reduced lipid concentrations in spawning females from these reefs, indicated a reduction in energy stores, constituting a sublethal and potential delayed effect on populations.

Reduced energy reserves in mesopredators could lead to energy allocation trade‐offs, and decreased growth rates, fecundity and survivorship, resulting in potential population declines in the longer term.

A plain language summary is available for this article.
A prediction model for frequency spectrum of blast‐induced seismic wave in viscoelastic medium
Authors: Yu Chenglong , Wang Zhongqi , Han Wengong 
Published: November 2017

ABSTRACTA prediction model for frequency spectrum of blast‐induced seismic waves is established. The effect of explosive sources is considered in this model. Our model implies that the frequency spectrum of blast‐induced seismic wave is mainly influenced by the initial pressure and the adiabatic exponent of explosives. The dominant frequency increases with the decreasing of initial pressure or the increasing of adiabatic exponent. In addition, this prediction model is verified by the experiment. The error of the dominant frequency is 4%–6%. It is indicated that the proposed model in this paper can reasonably predict the frequency spectrum of blast‐induced seismic waves, and then, we can provide a better frequency spectrum by optimizing the explosion source.
Experimental investigation of alternative transmission functions: Quantitative evidence for the importance of nonlinear transmission dynamics in host–parasite systems
Authors: Orlofske Sarah A. , Flaxman Samuel M. , Joseph Maxwell B. , Fenton Andy , Melbourne Brett A. , Johnson Pieter T. J. 
Published: November 2017

Abstract

Understanding pathogen transmission is crucial for predicting and managing disease. Nonetheless, experimental comparisons of alternative functional forms of transmission remain rare, and those experiments that are conducted are often not designed to test the full range of possible forms.

To differentiate among 10 candidate transmission functions, we used a novel experimental design in which we independently varied four factors—duration of exposure, numbers of parasites, numbers of hosts and parasite density—in laboratory infection experiments.

We used interactions between amphibian hosts and trematode parasites as a model system and all candidate models incorporated parasite depletion. An additional manipulation involving anaesthesia addressed the effects of host behaviour on transmission form.

Across all experiments, nonlinear transmission forms involving either a power law or a negative binomial function were the best‐fitting models and consistently outperformed the linear density‐dependent and density‐independent functions. By testing previously published data for two other host–macroparasite systems, we also found support for the same nonlinear transmission forms.

Although manipulations of parasite density are common in transmission studies, the comprehensive set of variables tested in our experiments revealed that variation in density alone was least likely to differentiate among competing transmission functions. Across host–pathogen systems, nonlinear functions may often more accurately represent transmission dynamics and thus provide more realistic predictions for infection.
How disturbance and dispersal influence intraspecific structure
Authors: Fraser Ceridwen I. , Davies Ian D. , Bryant David , Waters Jonathan M. 
Published: November 2017

Abstract

Recent studies have suggested that spatial patterns of intraspecific diversity can be influenced by density‐dependent processes, which can inhibit effective migration of new lineages to established populations. How mechanisms such as dispersal and disturbance influence these processes is, however, still poorly understood.

We hypothesised that (1) species with leptokurtic dispersal (frequent on small scales but rare on larger scales) would show no spatial structure on small scales and strong structure on large scales, and (2) disturbance would influence the chance of genetic turnover in a population.

We tested these hypotheses using empirical genetic (mtDNA) data from field observations of a model taxon (the buoyant, forest‐forming kelp Durvillaea, which exhibits leptokurtic dispersal distribution), and by conducting simulation analyses.

Our data supported the first hypothesis, with no spatial structure detected on fine (metres) scales despite evidence of strong structure on larger (tens to hundreds of kilometres) scales. The second hypothesis was also supported, with simulations showing that disturbance increased the rate at which structure developed, and reduced the time to fixation (monopolisation by a single lineage). The chance of any lineage reaching fixation was directly related to its initial proportion in the population, and this relationship was unaffected by changes in disturbance size or dispersal capacity. We conclude that, in the absence of selection, extirpation is typically a prerequisite for population‐genetic “turnover”, with remnant (refugial) individuals otherwise outnumbering immigrants.

Synthesis. Disturbance plays a critical role in releasing density‐dependent blocks to colonisation, and thus enables lineage turnover within species. Our results indicate that although both disturbance size and dispersal capacity play important roles in the formation of spatial structure within species, unless a population is totally extirpated, establishment of genetic lineages from elsewhere (turnover) is unlikely even for species that can disperse well.
Direct and indirect controls on organic matter decomposition in four coastal wetland communities along a landscape salinity gradient
Authors: Stagg Camille L. , Baustian Melissa M. , Perry Carey L. , Carruthers Tim J. B. , Hall Courtney T. 
Published: November 2017

AbstractCoastal wetlands store more carbon than most ecosystems globally. As sea level rises, changes in flooding and salinity will potentially impact ecological functions, such as organic matter decomposition, that influence carbon storage. However, little is known about the mechanisms that control organic matter loss in coastal wetlands at the landscape scale. As sea level rises, how will the shift from fresh to salt‐tolerant plant communities impact organic matter decomposition? Do long‐term, plant‐mediated, effects of sea‐level rise differ from direct effects of elevated salinity and flooding?We identified internal and external factors that regulated indirect and direct pathways of sea‐level rise impacts, respectively, along a landscape‐scale salinity gradient that incorporated changes in wetland type (fresh, oligohaline, mesohaline and polyhaline marshes). We found that indirect and direct impacts of sea‐level rise had opposing effects on organic matter decomposition.Salinity had an indirect effect on litter decomposition that was mediated through litter quality. Despite significant variation in environmental conditions along the landscape gradient, the best predictors of above‐ and below‐ground litter decomposition were internal drivers, initial litter nitrogen content and initial litter lignin content respectively. Litter decay constants were greatest in the oligohaline marsh and declined with increasing salinity, and the fraction of litter remaining (asymptote) was greatest in the mesohaline marsh. In contrast, direct effects of salinity and flooding were positive. External drivers, salinity and flooding, stimulated cellulytic activity, which was highest in the polyhaline marsh.Synthesis. Our results indicate that as sea level rises, initial direct effects of salinity will stimulate decay of labile carbon, but over time as plant communities shift from fresh to polyhaline marsh, litter decay will decline, yielding greater potential for long‐term carbon storage. These findings highlight the importance of quantifying carbon loss at multiple temporal scales, not only in coastal wetlands but also in other ecosystems where plant‐mediated responses to climate change will have significant impacts on carbon cycling.
Regulation of thyroid sodium‐iodide symporter in different stages of goiter: Possible involvement of reactive oxygen species
Authors: Matos Lívia P L , Penha Ricardo Cortez Cardoso , Cardoso‐Weide Luciene C , Freitas Mariana L , Silva Diorney L S G , Ferreira Andrea C F 
Published: November 2017

SummaryNa+/I− symporter (NIS) transports iodide into thyrocytes, a fundamental step for thyroid hormone biosynthesis. Our aim was to evaluate NIS regulation in different status of goitrogenesis and its underlying mechanisms. Wistar rats were treated with methimazole (MMI) for 5 and 21 days, to achieve different status of goiter. We then evaluated the effect of MMI removal for 1 day (R1d), after 5 (R1d‐5d) or 21 (R1d‐21d) days of MMI treatment. MMI increased thyroid weight, iodide uptake and in vitro TPO activity in a time‐dependent way. Although MMI removal evoked a rapid normalization of TPO activity in R1d‐5d, it was still high in R1d‐21d. On the other hand, iodide uptake was rapidly down‐regulated in R1d‐21d, but not in R1d‐5d, suggesting that the increased TPO activity in R1d‐21d led to increased intraglandular organified iodine (I‐X), which is known to inhibit iodide uptake. Since TGFβ has been shown to mediate some effects of I‐X, we evaluated TGFβ and TGFβ receptor mRNA levels, which were increased in R1d‐21d. Moreover, it has been demonstrated that TGFβ stimulates NOX4. Accordingly, our data revealed increased NOX4 expression and H2O2 generation in R1d‐21d. Finally, we evaluated the effect of H2O2 on NIS function and mRNA levels in PCCL3 thyroid cell line, which were reduced. Thus, the present study suggests that there is a relationship between the size of the goiter and NIS regulation and that the mechanism might involve I‐X, TGFβ, NOX4 and increased ROS production.
Interactive effects of morphine and dopamine receptor agonists on spatial recognition memory in mice
Authors: Chen Yanmei , Fu Yu , An Yingjie , Cao Jun , Wang Jianhong , Zhang Jichuan 
Published: November 2017

SummaryBoth opiates and dopamine play important roles in learning and memory. Although synergistic action between these two neurotransmitters has been found, their functional roles remain unclear. Here, low dose morphine (2.5 mg/kg) and low dose dopamine receptor agonists (apomorphine 0.05 mg/kg; SKF38393 0.01 mg/kg; bromocriptine 0.05 mg/kg), which have no effects on spatial recognition memory, were injected intraperitoneally into mice 30 minutes before a memory test in a two‐trial recognition Y‐maze. The Y‐maze is based on the innate tendency of rodents to explore novel environments and is therefore suitable for exploring the effects of morphine on learning and memory. Our results showed that both D1‐like and D2‐like dopamine receptor agonists dose‐dependently impaired the retrieval of spatial recognition memory in the Y‐maze, and co‐administration of memory ineffective doses of apomorphine (0.05 mg/kg), SKF38393 (0.01 mg/kg), or bromocriptine (0.05 mg/kg) and of morphine (2.5 mg/kg) resulted in impaired spatial recognition memory retrieval in mice. These findings suggest the existence of interactions between morphine and dopamine receptor agonists in memory processing and that activation of the dopamine system might contribute to morphine‐induced impairment of memory, which could provide insight into human addiction.
Associations of lifestyle factors with serum dehydroepiandrosterone sulphate and insulin‐like growth factor‐1 concentration in prepubertal children
Authors: Mäntyselkä Aino , Jääskeläinen Jarmo , Eloranta Aino‐Maija , Väistö Juuso , Voutilainen Raimo , Ong Ken , Brage Søren , Lakka Timo A. , Lindi Virpi 
Published: November 2017

SummaryObjectiveLittle is known about the relationships of dietary factors, physical activity and sedentary behaviour to dehydroepiandrosterone sulphate (DHEAS) and insulin‐like growth factor‐1 (IGF‐1) concentrations among prepubertal children. Therefore, we studied the associations of these lifestyle factors with serum DHEAS and IGF‐1 in children.Design and subjectsCross‐sectional analysis of a population sample of 431 prepubertal children aged 6‐9 years.MeasurementsAssessment of dietary factors by food records and physical activity and sedentary behaviour by a combined heart rate and movement monitor and a questionnaire. Measurement of serum DHEAS and IGF‐1.ResultsConsumption of low‐fibre grain products (standardized regression coefficient β = .118, P = .017) and intake of vegetable protein (β = .100, P = .045) was positively and consumption of sugar‐sweetened beverages (β = −.117, P = .018) was inversely associated with DHEAS after adjustment for sex, age and body fat percentage. Energy intake (β = .160, P = .001) was positively associated with IGF‐1 adjusting for sex, age and body fat percentage. Vigorous physical activity was inversely associated with DHEAS after adjustment for sex and age (β = −.120, P = .027), and total (β = −.137, P = .007), moderate (β = −.130, P = .012), vigorous (β = −.136, P = .011) and moderate to vigorous physical activity (β = −.160, P = .003) were inversely and total sedentary behaviour (β = .151, P = .003) was positively associated with IGF‐1 adjusting for sex and age. None of physical activity measures was associated with DHEAS or IGF‐1 after additional adjustment for body fat percentage.ConclusionsLifestyle factors have weak and moderate associations with biochemical markers of adrenarche in prepubertal children. These associations indicate body fat independent and dependent influences of diet and physical activity, respectively.
Acupuncture inhibits TXNIP‐associated oxidative stress and inflammation to attenuate cognitive impairment in vascular dementia rats
Authors: Du Si‐Qi , Wang Xue‐Rui , Zhu Wen , Ye Yang , Yang Jing‐Wen , Ma Si‐Ming , Ji Cai‐Shuo , Liu Cun‐Zhi 
Published: November 2017

SummaryAimsOxidative stress and inflammation have been implicated in the pathogenesis of vascular dementia (VD). Thioredoxin‐interacting protein (TXNIP) plays a vital role in oxidative stress and NOD‐like receptor protein 3 (NLRP3) inflammasome activation. There is evidence that acupuncture has an antioxidative and neuroprotective effect in VD. In this study, we investigated whether acupuncture can attenuate cognitive impairment via inhibiting TXNIP‐associated oxidative stress and inflammation in VD rats.MethodsBoth common carotid arteries were occluded (2‐vessel occlusion [2VO]) in rats to model VD. The neuroprotective effect of acupuncture was assessed by the Morris water maze and Nissl staining. Oxidative stress was assessed by detecting levels of reactive oxygen species, DNA oxidation, and antioxidase. Western blot, real‐time PCR, and immunofluorescence were used to detect the expression of TXNIP, NLRP3, caspase‐1, and IL‐1β. A TXNIP siRNA intraventricular injection was applied to investigate whether acupuncture mimicked the effect of TXNIP inhibitor.ResultsOur findings demonstrated that VD rats treated with acupuncture had reduced hippocampal neuronal loss and oxidative stress. The upregulation of TXNIP, NLRP3, caspase‐1, and IL‐1β induced by 2VO was also reversed by acupuncture. Furthermore, TXNIP siRNA had a similar effect as acupuncture on cognition, hippocampal neurons, and ROS production in VD rats.ConclusionIn conclusion, our study suggests that the neuroprotective effects of acupuncture in VD are mediated through reducing expression of TXNIP‐associated oxidative stress and inflammation.
Enhancing engineered vascular networks in vitro and in vivo: The effects of IGF1 on vascular development and durability
Authors: Friedrich Claudia C. , Lin Yunfeng , Krannich Alexander , Wu Yinan , Vacanti Joseph P. , Neville Craig M. 
Published: November 2017

AbstractObjectivesCreation of functional, durable vasculature remains an important goal within the field of regenerative medicine. Engineered biological vasculature has the potential to restore or improve human tissue function. We hypothesized that the pleotropic effects of insulin‐like growth factor 1 (IGF1) would enhance the engineering of capillary‐like vasculature.Materials and methodsThe impact of IGF1 upon vasculogenesis was examined in in vitro cultures for a period of up to 40 days and as subcutaneous implants within immunodeficient mice. Co‐cultures of human umbilical vein endothelial cells and human bone marrow‐derived mesenchymal stem cells in collagen‐fibronectin hydrogels were supplemented with either recombinant IGF1 protein or genetically engineered cells to provide sustained IGF1. Morphometric analysis was performed on the vascular networks that formed in four concentrations of IGF1.ResultsIGF1 supplementation significantly enhanced de novo vasculogenesis both in vitro and in vivo. Effects were long‐term as they lasted the duration of the study period, and included network density, vessel length, and diameter. Bifurcation density was not affected. However, the highest concentrations of IGF1 tested were either ineffective or even deleterious. Sustained IGF1 delivery was required in vivo as the inclusion of recombinant IGF1 protein had minimal impact.ConclusionIGF1 supplementation can be used to produce neovasculature with significantly enhanced network density and durability. Its use is a promising methodology for engineering de novo vasculature to support regeneration of functional tissue.
The pretreatment neutrophil‐lymphocyte ratio may predict prognosis of patients with liver cancer: A systematic review and meta‐analysis
Authors: Min Guang‐Tao , Li Yu‐Min , Yao Nan , Wang Jun , Wang Hong‐Peng , Chen Wei 
Published: November 2017

AbstractBackgroundAt present, several studies have reported that the pretreatment neutrophil‐lymphocyte ratio (NLR) may be associated with the prognosis of liver cancer. Nevertheless, their conclusions remain controversial. Thus, we performed a meta‐analysis of 54 studies to evaluate the prognostic value of NLR.MethodDatabases including PubMed, Embase, Cochrane Library, and Web of Science were searched to July 2017.ResultA total of 54 studies including 12 979 patients were included in this meta‐analysis. Elevated NLR had a close relationship with the overall survival (OS) (HR 1.52; 95% CI 1.39‐1.67), recurrence‐free survival (RFS) (HR 1.84; 95% CI 1.48‐2.30), and disease‐free survival (DFS) (HR 1.71; 95% CI 1.39‐2.11) of liver cancer, respectively. In addition, elevated NLR was associated with the presence of tumor vascular invasion (OR 2.35; 95% CI 1.93‐2.86), multiple tumors (OR 1.38; 95% CI 1.15‐1.66), alpha‐fetoprotein ≥ 400 ng/mL (OR 1.51; 95% CI 1.15‐1.98), presence of HbsAg (+) (OR 0.68; 95% CI 0.51‐0.90), and cirrhosis (OR: 0.59; 95% CI 0.44‐0.80).ConclusionThis meta‐analysis indicated that elevated NLR may be an effective and noninvasive indicator for prognosis of patients with liver cancer.
Long‐term efficacy and safety of canagliflozin in combination with insulin in Japanese patients with type 2 diabetes mellitus
Authors: Inagaki Nobuya , Harashima Shin‐ichi , Kaku Kohei , Kondo Kazuoki , Maruyama Nobuko , Otsuka Makiko , Kawaguchi Yutaka , Iijima Hiroaki 
Published: November 2017

AimThe aim of this study was to assess the long‐term efficacy and safety of canagliflozin as add‐on therapy in Japanese patients with type 2 diabetes mellitus who had inadequate glycaemic control with insulin.Materials and methodsThe study comprised a 16‐week, double‐blind period in which patients were randomized to either placebo (P; N = 70) or canagliflozin (100 mg, CAN; N = 76), followed by a 36‐week open‐label period in which all patients received canagliflozin. The efficacy endpoints included the change in HbA1c from baseline to end of treatment. The safety endpoints were adverse events, hypoglycaemic events, and laboratory test values.ResultsThe changes from baseline (mean ± standard deviation, last observation carried forward) in the P/CAN and CAN/CAN groups, respectively, were −1.09% ± 0.85% and −0.88% ± 0.86% for HbA1c, −1.40% ± 2.54% and −2.14% ± 2.75% for body weight, and 7.84% ± 14.37% and 8.91% ± 10.80% for HOMA2‐%B (all, P < .001). Adverse events occurred in 85.1% of the P/CAN group and 92.0% of the CAN/CAN group. Hypoglycaemic events occurred in 43.3% and 54.7%, respectively. All hypoglycaemic events were mild in severity and insulin dose reduction decreased the incidence rate of hypoglycaemic events. Post‐hoc ordinal logistic modelling/logistic modelling showed that lower serum C‐peptide at Week 0 was a risk factor for hypoglycaemia in both the P and CAN groups in the double‐blind period as well as in the canagliflozin all‐treatment period.ConclusionsThis study demonstrates the long‐term efficacy and safety of canagliflozin combined with insulin in Japanese patients.
Use of viscoelastic tests to predict clinical thromboembolic events: A systematic review and meta‐analysis
Authors: Harahsheh Yusrah , Ho Kwok M. 
Published: November 2017

AbstractWe aimed to assess whether whole‐blood viscoelastic tests are useful to identify patients who are hypercoagulable and at increased risk of thromboembolism. Two investigators independently analyzed studies in the MEDLINE, EMBASE, and Cochrane controlled trial register databases to determine the ability of viscoelastic tests to identify a hypercoagulable state that is predictive of objectively proven thromboembolic events. Forty‐one eligible studies, including 10,818 patients, were identified and subject to meta‐analysis. The majority of the studies (n = 36, 88%) used the maximum clot strength to identify a hypercoagulable state which had a moderate ability to differentiate between patients who developed thromboembolic events and those who did not (area under the summary receiver operating characteristic [sROC] curve = 0.70, 95% confidence interval [CI]: 0.65‐0.75). The pooled sensitivity, specificity, and diagnostic odds ratio to predict thromboembolism were 56% (95%CI: 44‐67), 76% (95%CI: 67‐83), and 3.6 (95%CI: 2.6‐4.9), respectively. The predictive performance did not vary substantially between patient populations, and publication bias was not observed. Current evidence suggests that whole‐blood viscoelastic tests have a moderate ability to identify a variety of patient populations with an increased risk of thromboembolic events and can be considered as a useful adjunct to clinical judgment to stratify a patient's risk of developing thromboembolism.