bluuebunny/crossref_metadata_2025_split huggingface dataset:
H2S modulates duodenal motility in male rats via activating TRPV1 and KATP channels
Authors: Lu Wen , Li Jing , Gong Liping , Xu Xiaomeng , Han Ting , Ye Yanfang , Che Tongtong , Luo Yan , Li Jingxin , Zhan Renzhi , Yao Wei , Liu Kejing , Cui Shuang , Liu Chuanyong 
Published: December 2013

Background and PurposeH2S induces vasodilatation by opening KATP channels but it may also affect other ion channels. The aim of this study was to investigate the effect of H2S on intestinal motility in rats and its underlying mechanism.Experimental ApproachThe tension of intestinal muscle strips, afferent firing of intestinal mesenteric nerves, length of duodenal smooth muscle cells and whole‐cell membrane potential of dorsal root ganglion (DRG) neurons were monitored. H2S‐producing enzymes were located by immunofluorescence staining.Key resultsNaHS exerted early transient excitation and late long‐lasting inhibition on the intestinal contraction. The excitation was attenuated by TRPV1 antagonists capsazepine, A784168, SB‐366791 and NK1 receptor antagonist L703606, while the inhibition was attenuated by glibenclamide. NaHS increased duodenal afferent nerve firing and depolarized DRG neurons. These effects were reduced by capsazepine and A784168. NaHS relaxed isolated duodenal smooth muscle cells. The KATP channels were expressed in smooth muscle cells. Cystathionine β‐synthase and cystathionine γ‐lyase were expressed in rat duodenal myenteric neurons. L‐cysteine and S‐adenosyl‐L‐methionine increased the contraction of duodenal muscle strips, an effect attenuated by capsazepine and L703606.Conclusions and ImplicationsNaHS induces biphasic effects on intestinal motility in rats while endogenous H2S only exerts an excitatory effect. This transient excitatory effect might be mediated by activation of TRPV1 channels in sensory nerve terminals with the consequent release of substance P. The long‐lasting inhibitory effect might be mediated by activation of KATP channels in the smooth muscle cells. These findings reveal a novel mechanism for the excitatory effect of H2S on gastrointestinal motility.
5‐Lipoxygenase and cysteinyl leukotriene receptor 1 regulate epidermal growth factor‐induced cell migration through Tiam1 upregulation and Rac1 activation
Authors: Magi Shigeyuki , Takemoto Yasushi , Kobayashi Hiroki , Kasamatsu Masato , Akita Takahiro , Tanaka Ayako , Takano Kei , Tashiro Etsu , Igarashi Yasuhiro , Imoto Masaya 
Published: December 2013

Cell migration is an essential step for tumor metastasis. The small GTPase Rac1 plays an important role in cell migration. Previously, we reported that epidermal growth factor (EGF) induced two waves of Rac1 activation; namely, at 5 min and 12 h after stimulation. A second wave of EGF‐induced Rac1 activation was required for EGF‐induced cell migration, however, the spatiotemporal regulation of the second wave of EGF‐induced Rac1 activation remains largely unclear. In this study, we found that 5‐lipoxygenase (5‐LOX) is activated in the process of EGF‐induced cell migration, and that leukotriene C4 (LTC4) produced by 5‐LOX mediated the second wave of Rac1 activation, as well as cell migration. Furthermore, these effects caused by LTC4 were found to be blocked in the presence of the antagonist of cysteinyl leukotriene receptor 1 (CysLT1). This blockage indicates that LTC4‐mediated CysLT1 signaling regulates the second EGF‐induced wave of Rac1 activation. We also found that 5‐LOX inhibitors, CysLT1 antagonists and the knockdown of CysLT1 inhibited EGF‐induced T cell lymphoma invasion and metastasis‐inducing protein 1 (Tiam1) expression. Tiam1 expression is required for the second wave of EGF‐induced Rac1 activation in A431 cells. Therefore, our results indicate that the 5‐LOX/LTC4/CysLT1 signaling pathway regulates EGF‐induced cell migration by increasing Tiam1 expression, leading to a second wave of Rac1 activation. Thus, CysLT1 may serve as a new molecular target for antimetastatic therapy. In addition, the CysLT1 antagonist, montelukast, which is used clinically for allergy treatment, might have great potential as a novel type of antimetastatic agent.
The impact of early cytomegalovirus infection after kidney transplantation on long‐term graft and patient survival
Authors: Smedbråten Yuliya V. , Sagedal Solbjørg , Leivestad Torbjørn , Mjøen Geir , Osnes Kåre , Rollag Halvor , Reisæter Anna V. , Foss Aksel , Os Ingrid , Hartmann Anders 
Published: December 2013

AbstractThis prospective observational cohort study is an extension of a previous study reporting effects of cytomegalovirus (CMV) on graft and patient survival in 471 patients who underwent kidney transplantation between 1994 and 1997. CMV pp65 antigen was measured every 7–14 d during the first three months after transplantation, given as number of CMV pp65‐positive cells per 105 leukocytes. A positive test was defined as CMV infection. None of the patients received CMV prophylaxis or preemptive treatment. During a median of 13.7 (7.1–14.9) yr, the number of death‐censored graft losses was 118 (25%) and of patient deaths 224 (48%). CMV infection was an independent significant risk factor for mortality in multivariate analysis (HR = 1.453, 95% CI 1.033–2.045, p = 0.032), adjusting for patient and donor age, preemptive transplantation, HLA‐DR and ‐AB mismatches, living donor, acute rejection during the first three months, donor–recipient CMV IgG antibody status and diabetic nephropathy. In univariate analysis, CMV infection was significantly associated with death‐censored graft loss but the association was not significant in multivariate model. CMV infection early after kidney transplantation is a predictor of overall mortality but not of death‐censored graft loss after a median observation period of 13.7 yr.
Clinical outcomes among renal transplant recipients with pre‐transplant weakly reactive donor‐specific antibodies
Authors: Yoo Peter S. , Bonnel Alexander , Kamoun Malek , Levine Matthew H. 
Published: December 2013

AbstractBackgroundAlloantibody can lead to antibody‐mediated rejection and graft loss in renal transplantation, necessitating an assessment of cross‐match compatibility. Within the past decade, more specific solid phase assays of alloantibody have been widely adopted, allowing virtual cross‐matching based on unacceptable antigens, the threshold of which is determined by individual centers.MethodsWe examined the clinical outcomes of 482 patients transplanted 2007–2009 in a single center, focusing on 30 patients with weakly reactive donor‐specific antibody (DSA) determined prospectively prior to renal transplant.ResultsCompared with patients without DSA, patients with weakly reactive DSA do not have increased rates of antibody‐mediated rejection, cellular rejection, or graft loss despite conventional immunosuppression utilization.ConclusionsUsing the screening methodology and immunosuppression regimen, we have applied to the patients with weak DSA allows them to be transplanted with equivalent outcomes as those without DSA, despite the overall higher risk characteristics of the patients in the weak DSA group.
Mountain landscapes offer few opportunities for high‐elevation tree species migration
Authors: Bell David M. , Bradford John B. , Lauenroth William K. 
Published: December 2013

AbstractClimate change is anticipated to alter plant species distributions. Regional context, notably the spatial complexity of climatic gradients, may influence species migration potential. While high‐elevation species may benefit from steep climate gradients in mountain regions, their persistence may be threatened by limited suitable habitat as land area decreases with elevation. To untangle these apparently contradictory predictions for mountainous regions, we evaluated the climatic suitability of four coniferous forest tree species of the western United States based on species distribution modeling (SDM) and examined changes in climatically suitable areas under predicted climate change. We used forest structural information relating to tree species dominance, productivity, and demography from an extensive forest inventory system to assess the strength of inferences made with a SDM approach. We found that tree species dominance, productivity, and recruitment were highest where climatic suitability (i.e., probability of species occurrence under certain climate conditions) was high, supporting the use of predicted climatic suitability in examining species risk to climate change. By predicting changes in climatic suitability over the next century, we found that climatic suitability will likely decline, both in areas currently occupied by each tree species and in nearby unoccupied areas to which species might migrate in the future. These trends were most dramatic for high elevation species. Climatic changes predicted over the next century will dramatically reduce climatically suitable areas for high‐elevation tree species while a lower elevation species, Pinus ponderosa, will be well positioned to shift upslope across the region. Reductions in suitable area for high‐elevation species imply that even unlimited migration would be insufficient to offset predicted habitat loss, underscoring the vulnerability of these high‐elevation species to climatic changes.
Historical assemblage distinctiveness and the introduction of widespread non‐native species explain worldwide changes in freshwater fish taxonomic dissimilarity
Authors: Toussaint Aurèle , Beauchard Olivier , Oberdorff Thierry , Brosse Sébastien , Villéger Sébastien 
Published: December 2013

AbstractAimTaxonomic dissimilarity between assemblages can result from two processes – the replacement of species (turnover) and differences in richness – but it remains unclear how anthropogenic drivers (introductions and extirpations) affect these processes. Here, we investigate how historical patterns and anthropogenic drivers shape the changes in dissimilarity and its turnover component in freshwater fish assemblages both in historical (i.e. pre‐industrial) times and at the present day.LocationWorld‐wide.MethodsWe used a global database of fish assemblages in 1054 river basins throughout the world to quantify the change in turnover through its contribution to taxonomic dissimilarity between the two periods. We then used random forests to disentangle the relative roles of historical distinctiveness, species introductions and species extirpations on changes in dissimilarity and on the contribution of its turnover component.ResultsThe pairs of basins exhibited a decrease in the contribution of turnover to taxonomic dissimilarity of 82% and 61% in homogenized and differentiated pairs, respectively. The historical number of shared species and its change after species introductions and extirpations accounted for more than 60% of the change in dissimilarity and in the turnover contribution in the six biogeographical realms.Main conclusionsThe historically high distinctiveness between pairs of basins, due to a low number of shared species, has promoted high levels of taxonomic dissimilarity. The world‐wide changes in taxonomic dissimilarity among fish assemblages are to a large extent coupled to a decrease in the contribution of taxonomic turnover to taxonomic dissimilarity. Hence, the dissimilarity between assemblages declines with decreasing species replacement. These changes are mainly explained by introductions of a small set of widespread non‐native species, which promote an increase in the number of shared species. Alongside historical distinctiveness, species introduction processes can determine whether assemblages become more homogenized or more differentiated. Our results suggest that taxonomic differentiation can quickly turn to homogenization as the number of species introductions increase.
Informal Institutions and Horizontal Accountability: Protocols in the Chilean Budgetary Process
Authors: Araya Ignacio Arana 
Published: December 2013

Abstract
Studies of executive-legislative relations are usually based only on the analysis of formal institutions, although informal institutions also shape interbranch behavior. This omission leads to questionable results when scholars examine the capacity of state institutions to audit other public agencies and branches of government. This article explores how the protocols, an informal institution that shapes the Chilean budgetary negotiations, have increasingly allowed the congress to have a more relevant budgetary role than what the constitution permits. It argues that protocols accommodate some of the undesired consequences of a charter that is strongly biased toward the central government, and describes how this institution has departed from its stringent budgetary focus to encompass broader executive-legislative agreements that enhance the legislature's capacity to oversee the executive.
Viking Sagas: Six Degrees of Icelandic Separation Social Networks from the Viking Era
Authors: Mac Carron Pádraig , Kenna Ralph 
Published: December 2013

Abstract
The Icelandic sagas are thousand-year-old stories of brave deeds and lives and loves, with a cast of thousands – but how true to life are they? Pádraig Mac Carron and Ralph Kenna analyse the interactions between the characters and find that social networks of the Viking era were very similar to those of today.
Early influences on child satiety‐responsiveness: the role of weaning style
Authors: Brown A. , Lee M. D. 
Published: December 2013

SummaryBackgroundNutrition during infancy may have a long‐term impact upon weight gain and eating style. How infants are introduced to solid foods may be important. Traditionally, infants are introduced to solid foods via spoon‐feeding of purees. However, baby‐led weaning advocates allowing infants to self‐feed foods in their whole form. Advocates suggest this may promote healthy eating styles, but evidence is sparse. The aim of the current study was to compare child eating behaviour at 18–24 months between infants weaned using a traditional weaning approach and those weaned using a baby‐led weaning style.MethodsTwo hundred ninety‐eight mothers with an infant aged 18–24 months completed a longitudinal, self‐report questionnaire. In Phase One, mothers with an infant aged 6–12 months reported breastfeeding duration, timing of solid foods, weaning style (baby‐led or standard) and maternal control, measured using the Child Feeding Questionnaire. At 18–24 months, post‐partum mothers completed a follow‐up questionnaire examining child eating style (satiety‐responsiveness, food‐responsiveness, fussiness, enjoyment of food) and reported child weight.ResultsInfants weaned using a baby‐led approach were significantly more satiety‐responsive and less likely to be overweight compared with those weaned using a standard approach. This was independent of breastfeeding duration, timing of introduction to complementary foods and maternal control.ConclusionsA baby‐led weaning approach may encourage greater satiety‐responsiveness and healthy weight‐gain trajectories in infants. However, the limitations of a self‐report correlational study are noted. Further research using randomized controlled trial is needed.
Suitability of A European Nuclear Collection of Brassica oleracea L. Landraces to Grow at High Temperatures
Authors: Rodríguez V. M. , Soengas P. , Cartea E. , Sotelo T. , Velasco P. 
Published: December 2013

AbstractStatistical models predict that global warming will have a negative impact in crop yields in the next decades. Especially vulnerable are winter crops such as kales or cabbages (Brassica oleracea L.). We evaluated the impact of high temperatures in morphological and biochemical traits of a B. oleracea core collection during early development. When grown at 30 °C, plants showed a reduction in chlorophyll content, early vigour and biomass compared with values observed on plants grown at 20 °C. Likewise, the total content of glucosinolates shows a reduction at high temperatures. The alboglabra group showed the best general performance at 30 °C for both morphological traits and glucosinolate content. Based on a cluster analysis, we selected four populations (MBG0072, MBG0464, MBG0535 and HRIGRU5555) as the most promising to be used in further breeding programs for heat tolerance.
Motor neuropathy‐associated mutation impairs Seipin functions in neurotransmission
Authors: Wei Shunhui , Soh Stephanie Li‐Ying , Xia Julia , Ong Wei‐Yi , Pang Zhiping P. , Han Weiping 
Published: December 2013

AbstractGain‐of‐toxic‐function mutations in Seipin (Asparagine 88 to Serine (N88S) and Serine 90 to Leucine (S90L) mutations, both of which disrupt the N‐glycosylation) cause autosomal dominant motor neuron diseases. However, the mechanism of how these missense mutations lead to motor neuropathy is unclear. Here, we analyze the impact of disruption of N‐glycosylation of Seipin on synaptic transmission by over‐expressing mutant Seipin in cultured cortical neurons via lentiviral infection. Immunostaining shows that over‐expressed Seipin is partly colocalized with synaptic vesicle marker synaptophysin. Electrophysiological recordings reveal that the Seipin mutation significantly decreases the frequency, but not the amplitudes of miniature excitatory post‐synaptic currents and miniature inhibitory post‐synaptic currents. The amplitude of both evoked excitatory post‐synaptic currents and inhibitory post‐synaptic current is also compromised by mutant Seipin over‐expression. The readily releasable pool and vesicular release probability of synaptic vesicles are both altered in neurons over‐expressing Seipin‐N88S, whereas neither γ‐amino butyric acid (GABA) nor α‐Amino‐3‐hydroxy‐5‐methyl‐4‐ isoxazolepropionic acid (AMPA) induced whole cell currents are affected. Moreover, electron microscopy analysis reveals decreased number of morphologically docked synaptic vesicles in Seipin‐N88S‐expressing neurons. These data demonstrate that Seipin‐N88S mutation impairs synaptic neurotransmission, possibly by regulating the priming and docking of synaptic vesicles at the synapse.
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Motoneuropathy‐associated endoplasmic reticulum (ER) protein Seipin‐N88S mutation disrupts N‐glycosylation and decreased the frequency of miniature excitatory and inhibitory post‐synaptic currents (PSCs), and the amplitude of evoked excitatory and inhibitory PSCs. The readily releasable pool and synaptic vesicle (SV) release probability were reduced in neurons over‐expressing Seipin‐N88S, along with decreased number of docked vesicles. We propose that Seipin‐N88S mutation impairs synaptic neurotransmission by regulating the docking of synaptic vesicles.
LPS or ethanol triggers clathrin‐ and rafts/caveolae‐dependent endocytosis of TLR4 in cortical astrocytes
Authors: Pascual‐Lucas Maya , Fernandez‐Lizarbe Sara , Montesinos Jorge , Guerri Consuelo 
Published: December 2013

AbstractToll‐like receptor 4 (TLR4) activation and signalling in glial cells play critical roles in neurological disorders and in alcohol‐induced brain damage. TLR4 endocytosis upon lipopolysaccharide (LPS) stimulation regulates which signalling pathway is activated, the MyD88‐dependent or the TIR‐domain‐containing adapter‐inducing interferon‐β (TRIF)‐dependent pathway. However, it remains elusive whether ethanol‐induced TLR4 signalling is associated with receptor internalization and trafficking, and which endocytic pathway(s) are used in cortical astrocytes. Using the adenoviral over‐expression of TLR4GFP, confocal microscopy and the imagestream technique, we show that upon ethanol or LPS stimulation, TLR4 co‐localizes with markers of the clathrin and caveolin endocytic pathways, and that this endocytosis is dependent on dynamin. Using chlorpromazin and filipin as inhibitors of the clathrin and rafts/caveolae endocytic pathways, respectively, we demostrate that TRIF‐dependent signalling relies on an intact clathrin pathway, whereas disruption of rafts/caveolae inhibits the MyD88‐ and TRIF‐dependent signalling pathways. Immunofluorescence studies also suggest that lipid rafts and clathrin cooperate for appropriate TLR4 internalization. We also show that ethanol can trigger similar endocytic pathways as LPS does, although ethanol delays clathrin internalization and alters TLR4 vesicular trafficking. Our results provide new insights into the effects of ethanol or LPS on TLR4 signalling in cortical astrocytes, events that may underlie neuroinflammation and brain damage.
imageThe results demonstrate that ethanol or lipopolysaccharide (LPS) triggers toll‐like receptor 4 (TLR4) endocytosis by caveolae and clathrin‐dependent pathways in astrocytes. We proposed that while clathrin is the protein responsible for TLR4 internalization, caveolin‐1/lipid rafts membrane microdomains are required for TLR4 signaling. The results provide new insights into the effects of ethanol on TLR4 signalling in astrocytes, events that may underlie neuroinflammation.
Reduction in DHA transport to the brain of mice expressing human APOE4 compared to APOE2
Authors: Vandal Milène , Alata Wael , Tremblay Cyntia , Rioux‐Perreault Christine , Salem Norman , Calon Frédéric , Plourde Mélanie 
Published: December 2013

AbstractBenefits on cognition from docosahexaenoic acid (DHA, 22 : 6 n‐3) intake are absent in humans carrying apolipoprotein E ε4 allele (APOE4), the most important genetic risk factor for Alzheimer's disease (AD). To test the hypothesis that carrying APOE4 impairs DHA distribution, we evaluated plasma and brain fatty acid profiles and uptake of [14C]‐DHA using in situ cerebral perfusion through the blood–brain barrier in 4‐ and 13‐month‐old male and female APOE‐targeted replacement mice (APOE2, APOE3, and APOE4), fed with a DHA‐depleted diet. Cortical and plasma DHA were 9% lower and 34% higher in APOE4 compared to APOE2 mice, respectively. Brain uptake of [14C]‐DHA was 24% lower in APOE4 versus APOE2 mice. A significant relationship was established between DHA and apoE concentrations in the cortex of mice (r2 = 0.21) and AD patients (r2 = 0.32). Altogether, our results suggest that lower brain uptake of DHA in APOE4 than in APOE2 mice may limit the accumulation of DHA in cerebral tissues. These data provide a mechanistic explanation for the lack of benefit of DHA in APOE4 carriers on cognitive function and the risk of AD.
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Using human APOE2, 3, and 4 isoform‐specific transgenic mice, we found a lower brain uptake of docosahexaenoic acid (DHA) in APOE4 than in APOE2 mice that may limit the biodistribution of DHA in cerebral tissues. These data provide a mechanistic explanation for the lack of benefit of DHA in APOE4 carriers on cognitive function and the risk of Alzheimer's disease (AD).