bluuebunny/crossref_metadata_2025_split huggingface dataset:
Population structure and conservation genetics of wild riceOryza rufipogon(Poaceae): a region‐wide perspective from microsatellite variation
Authors: Gao Lizhi 
Published: April 2004

AbstractOryza rufipogonGriff. is the most agriculturally important but seriously endangered wild rice species. To better estimate how genetic structure can be used to obtained a conservation perspective of the species, genetic variability at six polymorphic microsatellite DNA loci was examined. High levels of genetic variability were detected at six loci in 1245 individuals of 47 natural populations covering most of the species’ range in China (overallRS = 3.0740,HO = 0.2290,HS = 0.6700). Partitioning of genetic variability (FST = 0.246) showed that most microsatellite variation was distributed within populations. Significant departures from Hardy–Weinberg expectations and very strong linkage disequilibrium indicate a high degree of inbreeding in the species and severe subdivision within populations. A meanNmvalue of 0.7662 suggested a limited gene flow among the assayed populations. Our study suggests that conservation and restoration genetics should focus in particular on the maintenance of historically significant processes such as high levels of outbreeding and gene flow and large effective population size in the species.
Genetic diversity across a vertebrate species’ range: a test of the central–peripheral hypothesis
Authors: Garner Trenton W. J. , Pearman Peter B. , Angelone Sonia 
Published: April 2004

AbstractAlthough it has been long presumed that population genetic variability should decrease as a species’ range margin is approached, results of empirical investigations remain ambiguous. Sampling strategies employed by many of these studies have not adequately sampled the entire range. Here we present the results of an investigation of population genetic diversity in a vertebrate species, the Italian agile frog, Rana latastei, sampled comprehensively across its entire range. Our results show that genetic variability is not correlated with population location with respect to the range periphery. Instead, the model that best explains the genetic variation detectable across the range is based on an east‐to‐west gradient of declining diversity. Although we cannot state definitively what has led to this distribution, the most likely explanation is that the range of Rana latastei expanded postglacially from a Balkan refugium.
A population genetic comparison of argali sheep (Ovis ammon) in Mongolia using the ND5 gene of mitochondrial DNA; implications for conservation
Authors: Tserenbataa T. , Ramey R. R. , Ryder O. A. , Quinn T. W. , Reading R. P. 
Published: April 2004

AbstractWe sequenced 556 bp of the mitochondrial ND5 gene to infer aspects of population structure and to test subspecific designations of argali sheep (Ovis ammon) in Mongolia. Analysis of molecular variance (amova) revealed greater variation within than among putative subspecies and populations, suggesting high levels female‐mediated gene flow. Compared with bighorn sheep (O. canadensis) in North America, substantially less differentiation in mitochondrial DNA was found among argali populations over 1200 km than was found among bighorn populations over 250 km. This result is consistent with differences in argali and bighorn life history traits. Argali run for long distances across open terrain in the presence of a threat rather than running up into steep escape terrain like bighorn sheep do. Our results suggest recognizing only one Evolutionary Significant Unit (subspecies) of argali in Mongolia, but they may support recognizing two Management Units, because two regions do exhibit slightly different haplotype frequencies at the ND5 gene of mtDNA.
Three‐dimensional fine‐scale genetic structure of the neotropical epiphytic orchid, Laelia rubescens
Authors: Trapnell Dorset W. , Hamrick J. L. , Nason John D. 
Published: April 2004

AbstractEpiphytic plants occupy three‐dimensional space, which allows more individuals to be closely clustered spatially than is possible for populations occupying two dimensions. The unique characteristics of epiphytes can act in concert to influence the fine‐scale genetic structure of their populations which can, in turn, influence mating patterns and other population phenomena. Three large populations of Laelia rubescens (Orchidaceae) in the Costa Rican seasonal dry forest were sampled at two levels of intensity to determine: (i) whether individual clusters contain more than one genotype, and (ii) the spatial distribution and fine‐scale genetic structure of genotypes within populations. Samples were assayed for their multilocus allozyme genotypes and spatial autocorrelation analyses were performed. High levels of genetic diversity, high genotypic diversity and low among‐population variation were found. In the larger clusters, multiple genets per cluster were common with discrete clusters containing up to nine genotypes. Spatial autocorrelation analyses indicated significant positive genetic structure at distances of ≤ 45 cm. This result is likely due to the formation of discrete clusters by vegetative reproduction, as well as the establishment of sexually derived progeny within and near maternal clusters.
Dengue vector prevalence and virus infection in a rural area in south India
Authors: Tewari S. C. , Thenmozhi V. , Katholi C. R. , Manavalan R. , Munirathinam A. , Gajanana A. 
Published: April 2004

SummaryWe conducted a 2‐year (1997–1999) longitudinal, entomological and virological study in three dengue endemic villages in Vellore district, Tamil Nadu, to understand the dynamics of dengue transmission. Aedes aegypti (Linn.), Ae. albopictus (Skuse) and Ae. vittatus (Bigot) were the prevalent vector species. Aedes aegypti was breeding throughout the year with a Breteau index ranging from 9.05 to 45.49. Aedes albopictus and Ae. vittatus were prevalent mainly in the rainy season. Small water holding containers (cemented tanks/cisterns) were the perennial breeding source of Ae. aegypti, and its abundance was significantly higher in semi‐urbanized central areas than the peripheral areas of the villages. From 271 pools (4016 specimens) of adult females, eight dengue virus (DENV) isolates were obtained of which seven were from Ae. aegypti and one from Ae. albopictus. This is the first report of DENV isolation from Ae. albopictus in rural India. Infection rates in the two species were comparable. However, due to higher and perennial prevalence, Ae. aegypti is considered as primary vector with Ae. albopictus playing a secondary role. Despite circulation of all four serotypes (DENV 1–4) detected mainly during the transmission season, the high anthropophilic index of the vectors and their abundance, no human dengue case was reported, suggesting silent dengue transmission.
Epidemiological study of kala‐azar by direct agglutination test in two rural communities of eastern Nepal
Authors: Koirala S. , Karki P. , Das M. L. , Parija S. C. , Karki B. M. S. 
Published: April 2004

SummaryWe conducted a sero‐epidemiological study of kala‐azar in two endemic communities (Kasaini and Gidhaniya) situated in the Terai (plain) of eastern Nepal. Direct agglutination test (DAT) was used as a serological test for screening. Capillary blood samples were collected by filter paper method from 601 (96%) people of a total population of 628 in Kasaini and from 482 (94%) people of 515 in Gidhaniya. Positive DAT titres (1:2000) were found in 66 (6.09%) of 1083 sera tested. The male–female sero‐prevalence ratio was 1.44:1 and the age group of 15 years and above was most affected. Among the bone marrow aspirates collected from 66 DAT seropositive cases, only 19 were positive for Leishmania donovani (LD bodies). Of the 47 DAT seropositive but LD bodies’ negative cases, three were clinically active cases of kala‐azar. Another nine developed clinical symptoms of kala‐azar during 6 months follow‐up and 23 were cases that had received prior treatment for kala‐azar (within 1 year). The results of this study show the potential of the DAT on filter paper as a screening test for the surveillance of kala‐azar at a community level.
Detailed clinical and ultrasound examination of children and adolescents in a Schistosoma mansoni endemic area in Kenya: hepatosplenic disease in the absence of portal fibrosis
Authors: Vennervald Birgitte J. , Kenty LeeCarol , Butterworth Anthony E. , Kariuki Curtis H. , Kadzo Hilda , Ireri Edmund , Amaganga Clifford , Kimani Gachuhi , Mwatha Joseph , Otedo Amos , Booth Mark , Ouma John H. , Dunne David W. 
Published: April 2004

SummaryHepatosplenic schistosomiasis involving organomegaly, portal fibrosis and portal hypertension has been observed in autopsy studies. Here, we have tested the hypothesis that hepatosplenic disease including organomegaly and markers of increased portal pressure can occur in school aged children in the absence of fibrosis. A case‐only study of 96 children aged 7–20 years defined by ultrasound detectable hepatomegaly was undertaken in Makueni district, Kenya. A novel method of clinical examination that involved a consensus scoring by three or four examiners was used to classify children as presenting with severe or moderate hepatosplenic disease after palpation of livers and spleens. Ultrasound examination of livers and spleens was based on the Niamey protocol. Clinical measurements included spleen enlargement along the mid‐clavicular and mid‐axillary lines, liver enlargement along the mid‐sternal (MSL) and mid‐clavicular lines, as well as organ consistency. The clinical examination indicated that 9% and 60% of the children had severe or moderate hepatosplenomegaly, respectively. Amongst egg‐positive children, all clinical measurements, except MSL liver enlargement, correlated with egg count, as did portal vein diameter, spleen length and liver length measured by ultrasound. Peri‐portal fibrosis was not observed in any child, whereas 28% of the children were classified as having increased portal pressure according to World Health Organization criteria. There was no effect of malaria parasitaemia or hepatitis seropositvity on any of the observed parameters. These results indicate that hepatosplenic disease in school‐aged children attributable to S. mansoni infection, involving hepatosplenomegaly and increased portal vein diameter, can occur in the absence of peri‐portal fibrosis.
A randomized trial of amodiaquine and artesunate alone and in combination for the treatment of uncomplicated falciparum malaria in children from Burkina Faso
Authors: Barennes Hubert , Nagot Nicholas , Valea Innocent , Koussoubé‐Balima Tatiana , Ouedraogo Albert , Sanou Thérèse , Yé Suzanne 
Published: April 2004

SummaryCombining artesunate (AR) with existing antimalarial drugs may improve cure rates, delay emergence of resistance and reduce parasite clearance time. In order to investigate the latter, we conducted a randomized clinical trial testing the AR plus amodiaquine (AQ) combination for the treatment of uncomplicated Plasmodium falciparum malaria in Burkina Faso. Children aged 1–15 years were randomly assigned to either AQ (10 mg/kg) or AR (4 mg/kg first day then half dose) or AQ + AR (AQAR) as a single daily dose under supervision for three consecutive days for all groups. Follow‐up lasted 28 days. Primary endpoints were parasite and fever clearance time. Eighty‐seven children were evaluated: 27 received AQ, 27 AR and 33 AQAR. Using an intention to treat analysis, fever clearance time was similar in the three groups. However, it was significantly faster in the AR (1.21 days; P = 0.02) and AQAR groups (1.19 days; P < 0.01) than in the AQ group (1.46 days) when excluding other concomitant causes of fever. Parasite clearance time was faster in AR (1.13 days; P = 0.008) and AQAR groups (1.13 days; P < 0.01) than in the AQ group (1.6 days). All children cleared their parasites by day 14, including the child with Late Parasitological Failure (LPF) at day 7 after rescue treatment. Only one child (4%) from the AR group and one (4%) from the AQ group presented with asymptomatic parasitaemia at day 7 and day 21, respectively (LPF). Gametocyte carriage was not detectable in any group during follow‐up nor was any adverse reaction observed. While resistance to first‐line treatment (chloroquine) is already established in the country, AQ and AR used alone or in combination therapy proved highly efficacious in our study. Burkina Faso stands in a very good situation for an internationally recommended switch to AR‐containing combination as first‐line treatment for uncomplicated malaria. Including AQ in this regimen seems the best option.
Does sequencing the PKRBD of hepatitis C virus NS5A predict therapeutic response to combination therapy in an Australian population?
Authors: MACQUILLAN GERRY C , NIU XIANWA , SPEERS DAVID , ENGLISH SUZANNE , GARAS GEORGE , HARNETT GERRY B , REED WILLIAM D , ALLAN JANE E , JEFFREY GARY P 
Published: April 2004

AbstractBackground and Aim:  The presence of four or more amino acid substitutions within the interferon sensitivity determining region (ISDR) of the hepatitis C virus (HCV) genotype 1b NS5A gene determines sensitivity to interferon (IFN) monotherapy in Japanese patients. Resistance of HCV genotype 1 to IFN‐alpha has been attributed to the functional inhibition of a RNA dependent protein kinase (PKR) by the HCV NS5A PKR binding domain (PKRBD), which includes the ISDR. The ability of the ISDR and PKRBD sequence to predict a response to IFN‐alpha and ribavirin combination therapy was investigated in an Australian population.Methods:  The sequence of the PKRBD of NS5A, including the ISDR, for the dominant quasi‐species of HCV was determined in 37 genotype 1 (genotype 1a: n = 26, genotype 1b: n = 11) and 13 genotype 3a infected patients.Results:  The number of PKRBD amino acid substitutions in HCV genotype 1 infected patients with a sustained virological response was significantly higher than that in patients with a non‐response to treatment (P = 0.047). It was found that only 2/37 HCV genotype 1 infected patients had four or more amino acid substitutions relative to the prototype ISDR sequence (HCV‐J). Importantly, a sustained virological response was not found in any of the HCV infected patients who had a prototype ISDR genotype 1 sequence (n = 5).Conclusions:  There are relatively few amino acid mutations within the ISDR of this Western Australian patient population. Patients infected with a HCV genotype 1 prototype sequence should be counseled before receiving combination IFN‐alpha and ribavirin therapy as they have a poor response to treatment.
Ribavirin upregulates interleukin‐12 receptor and induces T cell differentiation towards type 1 in chronic hepatitis C
Authors: SHIINA MASAAKI , KOBAYASHI KOJU , SATOH HIROKO , NIITSUMA HIROFUMI , UENO YOSHIYUKI , SHIMOSEGAWA TOORU 
Published: April 2004

AbstractBackground and Aim:  The mechanisms of ribavirin as an immune modulator have not been fully revealed, contrary to its clinical benefit in chronic hepatitis C. Recently, host immune defense, especially cytotoxic T lymphocytes and T helper cells, have been considered to be closely related to the pathophysiology of chronic viral hepatitis. The aim of the present study was to evaluate the function of ribavirin in cellular immunity.Methods:  Peripheral blood mononuclear cells and total RNA were prepared from chronic hepatitis C patients. To evaluate the polarization of T helper cells, we performed intracellular cytokine assay and quantified the production of key cytokines. mRNA levels of interleukin‐12 receptor (IL‐12R), interferon (IFN)‐γ and interleukin‐4 (IL‐4) were measured by real time reverse transcription‐polymerase chain reaction (RT‐PCR).Results:  The population of T helper 1 cells increased significantly both in mitogen and hepatitis C virus (HCV) core protein stimulated cells with 0.1 µg/mL of ribavirin. However, the population of T helper 2 cells did not seem to be affected by ribavirin. The level of IL‐12R β2 chain mRNA was also upregulated to 130% after 24 h incubation with 0.1 µg/mL ribavirin (P = 0.037), whereas the β1 chain did not change significantly under these conditions. In addition, 0.1 µg/mL ribavirin could upregulate the levels of IFN‐γ or IL‐4 mRNA in some cases.Conclusion:  Ribavirin, perhaps by acting directly on CD4+ T cells, induces T cell differentiation towards type 1, depending on the upregulated signal of the IL‐12/IL‐12R pathway.
Barrett's esophagus: Prevalence and its relationship with dyspeptic symptoms
Authors: TORUNER MURAT , SOYKAN IRFAN , ENSARI ARZU , KUZU ISINSU , YURDAYDIN CIHAN , ÖZDEN ALI 
Published: April 2004

AbstractBackground and Aim:  Barrett's metaplasia is a premalign condition which plays a pivotal role in the development of esophageal adenocarcinoma. It is considered a complication of chronic gastroesophageal reflux disease. Although esophageal adenocarcinoma is an uncommon cancer, its incidence is rapidly increasing. The aims of the present study were to determine the prevalence of Barrett's metaplasia in outpatients referred for gastroscopy for upper gastrointestinal symptoms, and to clarify the relationship between Barrett's metaplasia and upper gastrointestinal symptoms.Methods:  Three‐hundred and ninety‐five consecutive dyspeptic patients, never previously investigated, underwent gastroscopy and were enrolled into the study.Results:  Barrett's metaplasia was detected in 29 patients (7.4%). The age‐specific prevalence of Barrett's metaplasia increased with age. In multivariate analysis, Barrett's metaplasia was independently and positively related to age, sex and duration of symptoms, but not with upper gastrointestinal symptoms. In univariate analysis, Barrett's metaplasia was significantly more common in patients with antral intestinal metaplasia (24%) and presence of hiatal hernia (65.5%), compared with those with normal endoscopic findings (6.2% and 39.2%, respectively, p = 0.001).Conclusion:  Symptoms do not predict Barrett's metaplasia. Barrett's metaplasia is age‐related and more common in patients with a longer duration of symptoms, presence of hiatal hernia and antral intestinal metaplasia.
‘Milking The Elephant’: Financial Markets as Real Markets in Kenya
Authors: Johnson Susan 
Published: April 2004

AbstractFinancial liberalization policies in the 1990s were intended to raise formal sector interest rates, enhance competition and expand access for users. This article investigates patterns of provision and use in a local financial market in Karatina, Kenya, at the end of the 1990s after a period of financial and economic liberalization. It takes a holistic approach, examining both formal and informal financial arrangements and microfinance interventions. This is because the role of the informal financial sector is particularly important for poor people and has received relatively little attention in the discussion of the consequences of reform. The author does this using a ‘real’ markets approach that sees markets as socially regulated and structured. Significant provision by the mutual sector (formal and informal), and poor lending performance by the banking sector is explained through an examination of the characteristics of the services on offer and their embeddedness in social relations, culture and politics.
The Negation of Politics in Participatory Development Projects, Kurnool, Andhra Pradesh
Authors: Chhotray Vasudha 
Published: April 2004

AbstractBased on a case study of two watershed development projects in Kurnool district of Andhra Pradesh in India, this article argues that participatory development projects are legitimized by using formalistic compliance criteria, while removing politics as a context. It shows how key aspects of the liberal political framework have not been fully harmonized with communitarian theories; the result is an interpretation of participation as a set of practices that are far removed from politics. As a development practice, participation can turn into the itemizing of participatory objectives, which are then to be fulfilled in the same way as physical and financial targets. The practitioners see their role as merely ‘technocratic’ and the projects they implement as ‘apolitical’. The author argues that, central to these claims, is a limited definition of ‘politics’ as a one dimensional domain comprising contest and irreconcilable conflict, from which the participatory projects, based on so‐called consensus, publicly expressed, are to be shielded. The article concludes that participatory projects accommodate and reflect existing relations of domination and control much more than their outward orientation would suggest.
Functional responses of plants to elevated atmospheric CO2– do photosynthetic and productivity data from FACE experiments support early predictions?
Authors: Nowak Robert S. , Ellsworth David S. , Smith Stanley D. 
Published: April 2004

SummaryResults from 16 free‐air CO2 enrichment (FACE) sites representing four different global vegetation types indicate that only some early predictions of the effects of increasing CO2 concentration (elevated [CO2]) on plant and ecosystem processes are well supported. Predictions for leaf CO2 assimilation (Anet) generally fit our understanding of limitations to photosynthesis, and the FACE experiments indicate concurrent enhancement of photosynthesis and of partial downregulation. In addition, most herbaceous species had reduced leaf nitrogen (N)‐content under elevated [CO2] and thus only a modest enhancement of Anet, whereas most woody species had little change in leaf N with elevated [CO2] but a larger enhancement of Anet. Early predictions for primary production are more mixed. Predictions that enhancement of productivity would be greater in drier ecosystems or in drier years has only limited support. Furthermore, differences in productivity enhancements among six plant functional types were not significant. By contrast, increases in productivity enhancements with increased N availability are well supported by the FACE results. Thus, neither a resource‐based conceptual model nor a plant functional type conceptual model is exclusively supported by FACE results, but rather both species identity and resource availability are important factors influencing the response of ecosystems to elevated [CO2].

Contents

Summary
1

I.
Introduction
2

II.
Early assessments of [CO2] responses in natural ecosystems
2

III.
Global network of FACE sites
4

IV.
Assimilation and leaf N‐content
5

V.
Primary productivity
13

VI.
Response of plant functional types
20

VII.
Conclusions
23

Acknowledgements
24

References
24
Gastric tonometry and monitoring gastrointestinal perfusion: using research to support nursing practice
Authors: Marshall Andrea P , West Sandra H 
Published: April 2004

Summary• The principles and physiological underpinnings of gastric tonometry are reviewed• Tonometric variables, including the PtCO2, pHi and CO2gap, are described and critiqued as measurements of gastrointestinal perfusion• Increases in gastrointestinal CO2unrelated to gastrointestinal hypoperfusion are discussed within different clinical contexts• The technical limitations of gastric tonometry, including procedural errors and PtCO2measurement are discussed in relation to the accuracy of tonometric measurements• Tonometric measurement using semi‐continuous air tonometry is introduced as a strategy to minimize technical limitations