bluuebunny/crossref_metadata_2025_split huggingface dataset:
Underlying mechanism of portal hypertensive gastropathy in cirrhosis: A hemodynamic and morphological approach
Authors: Curvêlo Lílian Amorim , Brabosa Walnei , Rhor Rachel , Lanzoni Valéria , Parise Edison Roberto , Ferrari Angelo Paulo , Kondo Mario 
Published: September 2009

AbstractBackground and Aim:  Portal hypertensive gastropathy (PHG) is an important cause of bleeding in patients with cirrhosis associated with portal hypertension. Histologically, the condition is characterized by dilation of the mucosal and submucosal vessels of the stomach; however, its mechanisms remain unclear. The aim of the present cross‐sectional study was to evaluate the role of portal and systemic hemodynamic features, humoral factors and hepatocellular function in the development and severity of PHG in patients with cirrhosis.Methods:  Forty‐six patients with cirrhosis of different etiologies underwent endoscopy. Portal hypertension was evaluated by hepatic venous pressure gradient (HVPG). The gastric mucosa was analyzed using two diagnostic methods: endoscopy according to the McCormack criteria and histological by histomorphometric analysis.Results:  The prevalence of PHG according to the endoscopic and histomorphometric methods was 93.4% and 76.1%, respectively. There were no statistically significant differences in HVPG measurements between the patients with mild (16.0 ± 5.9 mmHg) and severe PHG (16.9 ± 6.5 mmHg; P = 0.80) or between patients who did not have (15.2 ± 8.0 mmHg) and those who had PHG (16.3 ± 5.7 mmHg). No correlation was found between the presence or severity of PHG and systemic vascular resistance index (P = 0.53 and 0.34, respectively), Child–Pugh classification (P = 0.73 and 0.78, respectively) or glucagon levels (P = 0.59 and 0.62, respectively).Conclusions:  The present data show no correlation between the presence or the severity of PHG and portal pressure, Child–Pugh classification or systemic hemodynamics, suggesting that other factors may be involved in the physiopathology of PHG, such as local gastric mucosal factors or other underlying factors.
Effect of laparoscopic splenectomy on portal hypertensive gastropathy in cirrhotic patients with portal hypertension
Authors: Anegawa Go , Kawanaka Hirofumi , Uehara Hideo , Akahoshi Tomohiko , Konishi Kozo , Yoshida Daisuke , Kinjo Nao , Hashimoto Naotaka , Tomikawa Morimasa , Hashizume Makoto , Maehara Yoshihiko 
Published: September 2009

AbstractAim:  This study investigated the relationship between portal hypertensive gastropathy (PHG) and splenomegaly, and the effect of laparoscopic splenectomy on PHG in cirrhotic patients with portal hypertension.Methods:  Seventy patients with liver cirrhosis and portal hypertension were prospectively studied. Indication for laparoscopic splenectomy was bleeding tendency in 10 patients, induction of interferon in 45, treatment of hepatocellular carcinoma in seven, and treatment for endoscopic injection sclerotherapy‐resistant esophagogastric varices in eight. The severity of PHG was classified into none, mild, or severe according to the classification by McCormack et al. The severity of liver disease was classified using the Child–Pugh score. All patients underwent upper gastrointestinal endoscopy before and 1 month after the operation.Results:  The prevalence of PHG was significantly correlated with the severity of liver disease using the Child–Pugh score. The severity of PHG was significantly correlated with the resected spleen volume. One month after the operation, PHG was improved in 16 of 17 patients with severe PHG and in 12 of 32 with mild PHG. The Child–Pugh score showed a significant improvement (6.8 ± 1.4 to 6.2 ± 1.2) at 3 months after laparoscopic splenectomy (P < 0.0001).Conclusions:  PHG may be associated with splenomegaly, and laparoscopic splenectomy may have a beneficial effect on PHG, at least for a short time.
Inflammatory pseudotumors of the liver: Experience of a specialist surgical unit
Authors: Milias Konstantinos , Madhavan Krishna K , Bellamy Christopher , Garden Olivier J , Parks Rowan W 
Published: September 2009

AbstractBackground and Aim:  To present the experience in management of inflammatory liver pseudotumors from a specialist surgical unit and to review the medical literature on this rare manifestation.Methods:  Between 1995 and 2008, four patients were identified with this type of tumor from a total of 108 resected benign liver lesions at the Royal Infirmary of Edinburgh, Scotland UK. Two patients presented with liver abscesses, one with liver cystadenoma, and one with hilar cholangiocarcinoma. All four underwent some type of hepatectomy. We report these cases and review the literature.Results:  All four patients survived the operation with some morbidity.Conclusions:  Inflammatory liver pseudotumors are a difficult entity to identify. Resection should be considered because it may be impossible to rule out malignancy by other means.
Near‐ground solar radiation along the grassland–forest continuum: Tall‐tree canopy architecture imposes only muted trends and heterogeneity
Authors: BRESHEARS DAVID D. , LUDWIG JOHN A. 
Published: September 2009

AbstractSolar radiation directly and indirectly drives a variety of ecosystem processes. Our aim was to evaluate how tree canopy architecture affects near‐ground, incoming solar radiation along gradients of increasing tree cover, referred to as the grassland–forest continuum. We evaluated a common type of canopy architecture: tall trees that generally have their lowest level of foliage high above, rather than close to the ground as is often the case for shorter trees. We used hemispherical photographs to estimate near‐ground solar radiation using the metric of Direct Site Factor (DSF) on four sites in north Queensland, Australia that formed a grassland–forest continuum with tree canopy cover ranging from 0% to 71%. Three of the four sites had tall Eucalyptus trees with foliage several metres above the ground. We found that: (i) mean DSF exceeded >70% of the potential maximum for all sites, including the site with highest canopy cover; (ii) DSF variance was not highly sensitive to canopy coverage; and (iii) mean DSF for canopy locations beneath trees was not significantly lower than for adjacent intercanopy locations. Simulations that hypothetically placed Australian sites with tall tree canopies at other latitude–longitude locations demonstrated that differences in DSF were mostly due to canopy architecture, not specific site location effects. Our findings suggest that tall trees that have their lowest foliage many metres above the ground and have lower foliar density only weakly affect patterns of near‐ground solar radiation along the grassland–forest continuum. This markedly contrasts with the strong effect that shorter trees with foliage near the ground have on near‐ground solar radiation patterns along the continuum. This consequence of differential tree canopy architecture will fundamentally affect other ecosystem properties and may explain differential emphases that have been placed on canopy–intercanopy heterogeneity in diverse global ecosystem types that lie within the grassland–forest continuum.
Use of a δ13C–δ15N relationship to determine animal trophic positions in a tropical Australian estuarine wetland
Authors: ABRANTES KÁTYA , SHEAVES MARCUS 
Published: September 2009

AbstractStable isotope composition of organisms from different trophic groups collected from a semi‐isolated wetland pool in the Ross River estuary, northern Australia, was analysed to determine if there was a consistent relationship between δ13C, δ15N and trophic level that could be used to assign trophic positions. A strong linear negative relationship between δ13C and δ15N was detected for the three trophic levels considered (primary producers, primary consumers and secondary consumers). This relationship was consistent among trophic levels, differing only in height, that is, on δ15N values, which indicate trophic positions. A difference of 3.6–3.8‰ between trophic levels was present, suggesting a δ15N fractionation of approximately 3.7‰, a value slightly higher than the commonly assumed δ15N fractionation of approximately 3.4‰. The relationship between δ13C and δ15N was similar for invertebrate and fish primary consumers, indicating similar δ15N trophic fractionation for both groups, meaning trophic positions and trophic length could be reliably calculated based on either invertebrates or fish.
Non‐symbiotic nitrogen fixation during leaf litter decomposition in an old‐growth temperate rain forest of Chiloé Island, southern Chile: Effects of singleversusmixed species litter
Authors: PÉREZ CECILIA A. , CARMONA MARTÍN R. , ARMESTO JUAN J. 
Published: September 2009

AbstractHeterotrophic nitrogen fixation is a key ecosystem process in unpolluted, temperate old‐growth forests of southern South America as a source of new nitrogen to ecosystems. Decomposing leaf litter is an energy‐rich substrate that favours the occurrence of this energy demanding process. Following the niche ‘complementarity hypothesis’, we expected that decomposing leaf litter of a single tree species would support lower rates of non‐symbiotic N fixation than mixed species litter taken from the forest floor. To test this hypothesis we measured acetylene reduction activity in the decomposing monospecific litter of three evergreen tree species (litter C/N ratios, 50–79) in an old‐growth rain forest of Chiloé Island, southern Chile. Results showed a significant effect of species and month (anova, Tukey's test,P < 0.05) on decomposition and acetylene reduction rates (ARR), and a species effect on C/N ratios and initial % N of decomposing leaf litter. The lowest litter quality was that ofNothofagus nitida(C/N ratio = 78.7, lignin % = 59.27 ± 4.09), which resulted in higher rates of acetylene reduction activity (mean = 34.09 ± SE = 10.34 nmol h−1 g−1) and a higher decomposition rate (k = 0.47) thanPodocarpus nubigena(C/N = 54.4, lignin % = 40.31 ± 6.86, Mean ARR = 4.11 ± 0.71 nmol h−1 g−1,k = 0.29), andDrimys winteri(C/N = 50.6, lignin % = 45.49 ± 6.28, ARR = 10.2 ± 4.01 nmol h−1 g−1,k = 0.29), and mixed species litter (C/N = 60.7, ARR = 8.89 ± 2.13 nmol h−1g−1). We interpret these results as follows: in N‐poor litter and high lignin content of leaves (e.g.N. nitida) free‐living N fixers would be at competitive advantage over non‐fixers, thereby becoming more active. Lower ARR in mixed litter can be a consequence of a lower litter C/N ratio compared with single species litter. We also found a strong coupling betweenin situacetylene reduction and net N mineralization in surface soils, suggesting that as soon N is fixed by diazotroph bacteria it may be immediately incorporated into mineral soil by N mineralizers, thus reducing N immobilization.
Microhabitat relationships among five lizard species associated with granite outcrops in fragmented agricultural landscapes of south‐eastern Australia
Authors: MICHAEL DAMIAN R. , CUNNINGHAM ROSS B. , LINDENMAYER DAVID B. 
Published: September 2009

AbstractA fundamental part of developing effective biodiversity conservation is to understand what factors affect the distribution and abundance of particular species. However, there is a paucity of data on ecological requirements and habitat relationships for many species, especially for groups such as reptiles. Furthermore, it is not clear whether habitat relationships for particular species in a given environment are transferable to other environments within their geographical range. This has implications for the type of ‘landscape model’ used to guide management decisions in different environments worldwide. To test the hypothesis that species‐specific habitat relationships are transferable to other environments, we present microhabitat models for five common lizard species from a poorly studied habitat – insular granite outcrops, and then compared these relationships with studies from other environments in south‐eastern Australia. We recorded twelve species from five families, representing 699 individuals, from 44 outcrops in the south‐west slopes of New South Wales. Five lizard species were abundant and accounted for 95% of all observations: Egernia striolata, Ctenotus robustus, Cryptoblepharus carnabyi, Morethia boulengeri and Carlia tetradactyla (Scincidae). Linear regression modelling revealed suites of different variables related to the abundance patterns of individual species, some of which were broadly congruent with those measured for each species in other environments. However, additional variables, particular to rocky environments, were found to relate to reptile abundance in this environment. This finding means that species' habitat relationships in one habitat may not be readily transferable to other environments, even those relatively close by. Based on these data, management decisions targeting reptile conservation in agricultural landscapes, which contain rocky outcrops, will be best guided by landscape models that not only recognize gradients in habitat suitability, but are also flexible enough to incorporate intraspecies habitat variability.
Association between the Trail Making Test and physical performance in elderly Japanese
Authors: Hirota Chika , Watanabe Misuzu , Sun Wei , Tanimoto Yoshimi , Kono Rei , Takasaki Kyosuke , Kono Koichi 
Published: September 2009

Aim:  The Trail Making Test (TMT) is used in Western countries as an indicator of executive function, but there is little information regarding its use in Japan. Our previous initial study showed that the TMT was significantly associated with mobility‐related functions among elderly Japanese living in the community and in this study, we increased the number of participants to clarify that result.Methods:  The TMT, comprised of two parts (part A and part B), was administered to 493 subjects aged 65 years or older (164 men, 329 women). Our assessment used the time difference (ΔTMT) between parts B and A, and eight physical performance indicators: four of preventive care (usual walking speed, timed Up & Go [TUG], one‐leg standing balance and handgrip strength) and four movement parameters (maximum walking speed, dual‐task TUG, stair climbing and obstacle‐negotiating gait).Results:  The median ΔTMT score was 64.01 s for men and 65.56 s for women. The ΔTMT score increased with age, and there was no difference between sexes. Multinomial logistic regression analysis showed that a poor ΔTMT was related to low tertiles for all physical performances. It related to the intermediate tertile of TUG and maximum walking speed, dual‐task TUG, stair climbing and obstacle‐negotiating gait.Conclusion:  The TMT reflects complex walking performance, so it can be a useful synthetic indicator for health programs promoting independence in elderly Japanese.
Inbred mouse strains differ in multiple hippocampal activity traits
Authors: Jansen R. , Linkenkaer‐Hansen K. , Heistek T. , Timmerman J. , Mansvelder Huibert D. , Brussaard Arjen B. , De Gunst M. , Van Ooyen A. 
Published: September 2009

AbstractA major challenge in neuroscience is to identify genes that influence specific behaviors and to understand the intermediary neuronal mechanisms. One approach is to identify so‐called endophenotypes at different levels of neuronal organization from synapse to brain activity. An endophenotype is a quantitative trait that is closer to the gene action than behavior, and potentially a marker of neuronal mechanisms underlying behavior. Hippocampal activity and, in particular, hippocampal oscillations have been suggested to underlie various cognitive and motor functions. To identify quantitative traits that are potentially useful for identifying genes influencing hippocampal activity, we measured gamma oscillations and spontaneous activity in acute hippocampal slices from eight inbred mouse strains under three experimental conditions. We estimated the heritability of more than 200 quantitative traits derived from this activity. We observed significant differences between the different mouse strains, particularly in the amplitude of the activity and the correlation between activities in different hippocampal subregions. Interestingly, these traits had a low genetic correlation between the three experimental conditions, which suggests that different genetic components influence the activity in different conditions. Our findings show that several traits of hippocampal gamma oscillations and spontaneous activity are heritable and could thus be potentially useful in gene‐finding strategies based on endophenotypes.
Anopheles gambiae TRPA1 is a heat‐activated channel expressed in thermosensitive sensilla of female antennae
Authors: Wang Guirong , Qiu Yu T. , Lu Tan , Kwon Hyung‐Wook , Jason Pitts R. , Van Loon Joop J. A. , Takken Willem , Zwiebel Laurence J. 
Published: September 2009

AbstractHeat sensitivity is a sensory modality that plays a critical role in close‐range host‐seeking behaviors of adult female Anopheles gambiae, the principal Afrotropical vector for human malaria. An essential step in this activity is the ability to discriminate and respond to increases in environmental temperature gradients through the process of peripheral thermoreception. Here, we report on the characterization of the anopheline homolog of the transient receptor potential (TRP) A1/ANKTM1 channel that is consistent with its role as a heat‐sensor in host‐seeking adult female mosquitoes. We identify a set of distal antennal sensory structures that specifically respond to temperature gradients and express AgTRPA1. Functional characterization of AgTRPA1 in Xenopus oocytes supports its role in the molecular transduction of temperature gradients in An. gambiae, providing a basis for targeting mosquito heat responses as a means toward reducing malaria transmission.
Phylogenetic diversity of transition and anoxic zone bacterial communities within a near‐shore anoxic basin: Nitinat Lake
Authors: Schmidtova Jana , Hallam Steven J. , Baldwin Susan A. 
Published: September 2009

SummaryAt two stations surveyed in Nitinat Lake, a ∼200‐m‐deep anoxic tidal fjord, sulfide was detected as close as 15 m from the surface. Biological characterization, determined from small subunit ribosomal RNA gene sequencing, of the chemocline and anaerobic zone revealed many sequences related to sulfur‐oxidizing bacteria, suggesting that sulfur cycling is a dominant process. γ‐ and ε‐Proteobacteria related to thiotrophic symbionts, as well as Chlorobium sp., dominated the transition zone. These are expected to play a role in dark and phototrophic CO2 fixation, respectively. ε‐Proteobacteria phylotype abundance increased with depth, eventually comprising 69–97% of all sequences recovered from the anoxic zone. The vast majority (74%) of these phylotypes were affiliated with a novel Acrobacter sp. group (NITEP5). Quantification of NITEP5 revealed that up to 2.8 × 105 cells ml−1 were present in the anoxic zone. Surprisingly, although sequences related to known sulfate‐reducing bacteria were recovered from the transition zone, quantification of the dsr gene and 35SO42− uptake tests suggest that sulfate‐reduction within the water column is negligible. Overall, sequence diversity between different vertical zones was high, although the spatial segregation of γ‐Proteobacteria, Chlorobi, and ε‐Proteobacteria did not appear to vary significantly between seasons.
Virus resistance in the toxic bloom‐forming dinoflagellate Heterocapsa circularisquama to single‐stranded RNA virus infection
Authors: Tomaru Yuji , Mizumoto Hiroyuki , Nagasaki Keizo 
Published: September 2009

SummaryHcRNAV is the only known cultured dinoflagellate‐infecting RNA virus. Lysis of its host dinoflagellate Heterocapsa circularisquama caused by HcRNAV is followed by apparent cell regrowth. Here we investigate the mechanism supporting the survival phenomenon. The proportion of normal cells with intact nucleus decreased to ∼8% by 3 days post infection, and then, increased to > 90% at 15 days post infection. There were abnormal cells lacking an intact nucleus, and this was followed by propagation of virus‐resistant survivor cells. The proportion of HcRNAV‐resistant cells in three different subcultures and temporal fluctuations were compared: a clonal H. circularisquama culture without virus inoculation (virus‐sensitive, VS), a surviving isolate from the HcRNAV‐inoculated Culture‐VS incubated in autoclaved medium (virus‐resistant, VR) and a portion of Culture‐VR incubated with HcRNAV (VR incubated with virus, VR + V). The proportion of HcRNAV‐resistant cells in Culture‐VS was 0% and in Culture‐VR + V was > 94% during the experiment; and Culture‐VR fluctuated from 4% to 71%. Hence, the virus resistance was assumed to be reversible. Using Northern hybridization, viral genome accumulation was not detected in Culture‐VR + V cells either inoculated with HcRNAV or transfected with HcRNAV‐genome; thus, intracellular viral RNA replication was assumed to be interrupted in the virus‐resistant cells.
Identification and characterization of new LuxR/LuxI‐type quorum sensing systems from metagenomic libraries
Authors: Hao Youai , Winans Stephen C. , Glick Bernard R. , Charles Trevor C. 
Published: September 2009

SummaryQuorum sensing (QS) cell–cell communication systems are utilized by bacteria to coordinate their behaviour according to cell density. Several different types of QS signal molecules have been identified, among which acyl‐homoserine lactones (AHLs) produced by Proteobacteria have been studied to the greatest extent. Although QS has been studied extensively in cultured microorganisms, little is known about the QS systems of uncultured microorganisms and the roles of these systems in microbial communities. To extend our knowledge of QS systems and to better understand the signalling that takes place in the natural environment, metagenomic libraries constructed using DNA from activated sludge and soil were screened, using an Agrobacterium biosensor strain, for novel QS synthase genes. Three cosmids (QS6‐1, QS10‐1 and QS10‐2) that encode the production of QS signals were identified and DNA sequence analysis revealed that all three clones encode a novel luxI family AHL synthase and a luxR family transcriptional regulator. Thin layer chromatography revealed that these LuxI homologue proteins are able to synthesize multiple AHL signals. Tandem mass spectrometry analysis revealed that LuxIQS6‐1 directs the synthesis of at least three AHLs, 3‐O‐C14:1 HSL, 3‐O‐C16:1 HSL and 3‐O‐C14 HSL; LuxIQS10‐1 directs the synthesis of at least 3‐O‐C12 HSL and 3‐O‐C14 HSL; while LuxIQS10‐2 directs the synthesis of at least C8 HSL and C10 HSL. Two possible new AHLs, C14:3 HSL and (?)‐hydroxymethyl‐3‐O‐C14 HSL, were also found to be synthesized by LuxIQS6‐1.