bluuebunny/crossref_metadata_2025_split huggingface dataset:
Phylogeography and freshwater basins in central Mexico: recent history as revealed by the fish parasite Rhabdochona lichtenfelsi (Nematoda)
Authors: Mejía‐Madrid H. H. , Vázquez‐Domínguez E. , Pérez‐Ponce de León G. 
Published: February 2007

AbstractAim  The phylogeography of Rhabdochona lichtenfelsi, a nematode parasite specific to endemic goodeids in Mexico, is used to infer the biogeographical history of fragmentation and recent evolution of the Mesa Central drainages. Geological history of the west‐central region of Mexico suggests that extant freshwater basins are the result of different vicariant events that fragmented ancient watercourses and lakes within the Mesa Central.Location  Major freshwater river basins of the Mesa Central, Mexico: Ameca, Cotija, Lerma, Rio Verde, Panuco, and lakes Cuitzeo and Zacapu.Methods  Haplotype diversity and phylogeographical structure of 10 populations of R. lichtenfelsi, sampled from the complete range of this species, were analysed with partial sequences of cytochrome c oxidase subunit I (456 bp). Analyses performed included phylogenetic tree estimation methods (neighbour‐joining, maximum parsimony and maximum likelihood), genetic diversity, distance and structure estimates, and nested clade analysis.Results  High overall haplotype diversity, unique haplotypes, and strongly structured populations were found in the basins sampled. Three phylogenetically and demographically identifiable clades were recovered. These clades fit an isolation‐by‐distance model. Significant population expansion was observed for two clades and for the entire population. Time of divergence was estimated as 1.0 and 0.84 Ma for the different clades.Main conclusions  The distribution of R. lichtenfelsi haplotypes does not correspond to the present distribution of the basins of Mesa Central, but instead reflects the distribution of those basins during a recent geological period (Pleistocene). While our current knowledge of the evolution and geographical relationships of the Mesa Central basins comes from studies of freshwater fish encompassing a more ancient history, our results suggest that, during the past million years, old basins and connections existed where today isolated freshwater bodies stand, thus unravelling a novel biogeographical history for the Mesa Central of Mexico.
Holocene vegetation and climate change from near Lake Pedder, south‐west Tasmania, Australia
Authors: Fletcher Michael‐Shawn , Thomas Ian 
Published: February 2007

AbstractAim  To use surface pollen and vegetation relationships to aid the interpretation of a Holocene pollen record.Location  South‐west Tasmania, Australia.Methods  A survey was undertaken of surface‐pollen samples from the major regional vegetation types: alpine, rain forest and moorland. Relationships between vegetation type and surface‐pollen representation were analysed using twinspan classification and ordination. A core was retrieved from moorland vegetation, and interpretation of the fossil pollen sequence was aided using relationships detected in our surface‐pollen analysis.Results  Regional vegetation types are reflected in the pollen rain of south‐west Tasmania, despite the over‐representation of important rain forest tree species in samples from non‐forest sites. twinspan classification of the surface‐pollen samples identified the following indicator pollen taxa for each vegetation type: Astelia alpina (alpine); Lagarostrobos franklinii (rain forest); Leptospermum and Melaleuca (moorland). Detrended correspondence analysis of the surface‐pollen samples clearly separates samples from each vegetation type. Correlation of the ordination axes with environmental data identified a dominant temperature/altitudinal gradient in the surface‐pollen data (R = 0.852/0.844). Application of the results of the surface‐pollen analysis to the fossil sequence revealed that fire‐promoted moorland has dominated the local environment around the core site for the entire Holocene. Changes in fossil pollen composition also suggest that temperatures increased through the Late Glacial to peak in the mid‐Holocene and declined thereafter, a trend consistent with other sites in the region.Main conclusions  Pollen spectra can successfully be used to predict local vegetation in south‐west Tasmania. At least this part of inland south‐west Tasmania has remained forest‐free throughout the Holocene, conflicting with the dominant palaeoecological paradigm of a mid‐Holocene dominated by rain forest. A comparison with pollen records from moorland vegetation across the region suggests that fire‐promoted moorland has dominated the landscape since the Late Glacial. We suggest that burning by people through the Late Glacial (if not earlier) facilitated the spread of moorland throughout the region, greatly restricting the expansion of rain forest. The continued influence of fire throughout the Holocene in this perennially wet landscape argues for a revision of the dominant human‐occupation model that depicts an abandonment of the interior of south‐west Tasmania in the Late Glacial in response to the expansion of rain forest.
Spatial and temporal patterns of recent forest encroachment in montane grasslands of the Valles Caldera, New Mexico, USA
Authors: Coop Jonathan D. , Givnish Thomas J. 
Published: February 2007

AbstractAim  Recent forest encroachment into montane and subalpine grasslands has occurred in the Rocky Mountains and many other mountain ranges globally. The timing, rate, and extent of tree invasion can depend on interactions among topography, positive spatial feedbacks, and temporally variable factors (especially climate, grazing, and fire). Here we examine spatial and temporal patterns of tree invasion in the Valles Caldera of the Jemez Mountains.Location  This study was conducted in the Valles Caldera (35°50′–36°00′ N; 106°24′–106°37′ W), a 24‐km‐wide volcanic basin in northern New Mexico, USA. Grasslands in this otherwise forested region occur in broad valley bottoms of the caldera floor between 2575 and 2700 m, and on south‐facing slopes and mountain tops up to 3300 m.Methods  We used a GIS analysis of orthorectified aerial photos taken in 1935 and 1996, covering a 40,000‐ha study area, to quantify the extent of tree invasion and to assess its relationship to spatial factors. We obtained dates of establishment from 299 increment cores and basal disks from 50 sites in the Valles Caldera National Preserve (VCNP) to reconstruct temporal patterns of tree invasion.Results  The area of grasslands in our study area declined from 11,747 to 9336 ha (nearly 18%) between 1935 and 1996. Tree invasion increased with slope, elevation, and proximity to the previous tree line, but showed no relationship to aspect. Tree invasion was more rapid and continuous on upper mountain slopes, while the invasion of valley‐bottom grasslands below reversed tree lines was more episodic, and appeared to track mean summer minimum temperatures.Main conclusions  The rapid and continuous invasion of steep, high‐elevation slopes suggests that frequent fire was the single most important factor in maintaining grassy communities in these sites. The slower, episodic invasion of valley‐bottom grasslands, and the apparent relationship between increased invasion and years of higher summer minimum temperatures are consistent with the hypothesis that these grasslands have been maintained by low temperatures or frosts damaging to tree seedlings. We encourage prescribed fire to restore and maintain grasslands in the VCNP, especially small patches on steep, high‐elevation slopes.
Regional species richness in an obligate subterranean dwelling fauna – epikarst copepods
Authors: Pipan Tanja , Culver David C. 
Published: February 2007

AbstractAim  The diversity of the obligate cave‐dwelling fauna has proved difficult to measure because of the highly localized distributions of most species. We investigated: (1) the local and regional diversity patterns of a major component of the obligate cave‐dwelling fauna living in the epikarst zone, the karst layer closest to the surface; (2) variations in local and regional patterns of species richness; and (3) sampling sufficiency at multiple scales.Location  Caves in the Dinaric Mountains of Slovenia.Methods  We sampled continuously the abundance of 37 species of copepods dislodged from the epikarst from 35 ceiling drips in six caves for a period of one year. Copepods were collected in a specially designed net that allowed continuous collection.Results  Based on species accumulation curves and Chao estimates of total diversity, we determined that 3–4 months of continuous sampling were sufficient to find 90% of the species in a drip, that five drips were sufficient to find 90% of the species in a cave, and that five caves were sufficient to find 90% of the species in a region.Main conclusions  The epikarst copepod fauna is a significant part of the aquatic cave fauna, contributing about 20% at the regional level. Because of the scale of variation, much of which occurs within a cave, and because of the availability of continuous sampling devices, the epikarst component of subterranean diversity seems to be more thoroughly and accurately measured than do other components.
Specific language impairment as the prominent feature in a patient with a low‐level trisomy 21 mosaicism
Authors: Paoloni‐Giacobino A. , Lemieux N. , Lemyre E. , Lespinasse J. 
Published: February 2007

AbstractBackground  The extent and severity of the disabilities is variable among individuals with Down syndrome, although generally characterized by a range of physical and intellectual conditions, including language impairment. Whether the language deficit is due to the intellectual disability (ID) or associated to the supernumerary or portion of chromosome 21 is still debated.Methods  Karyotyping was performed on blood lymphocyte and skin fibroblasts. Fluorescence in situ hybridization analysis was performed on cultured lymphocytes and buccal smear cells.Results  The trisomy 21 (T21) mosaicism was characterized by 0.7–10% of mosaic cells in the different tissues, in a 14‐year‐old girl presenting an intellectual development within the normal range and specific language impairment (SLI) as the only prominent feature.Conclusion  This case illustrates the wide range of phenotypical abnormalities possibly associated with T21 mosaicism. We propose that SLI is indeed a phenotypic trait specific to Down syndrome rather than subsequent to the ID most often associated to the syndrome.
A functional Fas promoter polymorphism is associated with a severe phenotype in type 1 autoimmune hepatitis characterized by early development of cirrhosis
Authors: Agarwal K. , Czaja A. J. , Donaldson P. T. 
Published: February 2007

AbstractGenome scanning studies suggest an important role for genes outside the major histocompatibility complex in autoimmunity. Key candidates are those genes involved in immune regulation and preservation of immune homeostasis, including the genes involved in apoptosis. Our aim was to determine the association between the Fas gene polymorphism at position −670 and susceptibility, clinical expression, and outcome in type 1 autoimmune hepatitis (AIH). An adenosine to guanine single nucleotide polymorphism in the Fas gene (TNFRSF6) promoter was assessed in 149 well‐characterized Caucasoid patients and 172 matched controls. Patients and normal subjects had the similar TNFRSF6−670 allele and genotype frequencies. Serum aspartate aminotransferase (510 ± 77 vs 283 ± 53 U/l), γ‐globulin (3.3 ± 0.2 vs 2.6 ± 0.2 g/dl), and immunoglobulin G (2976 ± 223 vs 2324 ± 203 mg/dl) levels were higher in patients with the guanine/guanine genotype than in those with the adenosine/adenosine genotype. Cirrhosis at presentation was more common in patients with the adenosine/adenosine or adenosine/guanine genotypes than in those with the guanine/guanine genotype (29% vs 6%). Polymorphism of the Fas gene at position −670 does not influence susceptibility to AIH, but may affect the early development of cirrhosis.
HLA‐G14‐bp polymorphism at exon 8 in Amerindian populations from the Brazilian Amazon
Authors: Mendes‐Junior C. T. , Castelli E. C. , Simões R. T. , Simões A. L. , Donadi E. A. 
Published: February 2007

AbstractHLA‐G(human leukocyte antigen‐G) plays an important role in the modulation of the maternal immune system during pregnancy.HLA‐Galleles presenting a 14‐bp insertion at exon 8 have been associated with decreased messenger RNA levels, preeclampsia, and miscarriages. This suggests that natural selection may exert a strong influence against the insertion allele in isolated populations. DNA samples from 384 Amazonian Indians spread across seven isolated tribes were evaluated for the 14‐bp polymorphism. The insertion frequency (38.54%) was somewhat low. The Ewens–Watterson’s neutrality test showed a slight trend toward balancing selection operating at this locus but no correlation between the 14‐bp locus and fertility data was found. To sum up, no definitive evidence was obtained indicating that the 14‐bp frequencies in Amerindians depart from neutrality.
Association study of PTPN22 C1858T polymorphism in Trypanosoma cruzi infection
Authors: Robledo G. , González C. I. , Morillo C. , Martín J. , González A. 
Published: February 2007

AbstractIn this study we investigated a possible role for the single nucleotide polymorphism C1858T of the PTPN22 (protein tyrosine phosphatase nonreceptor 22) gene in determining the susceptibility to Trypanosoma cruzi infection, as well as in development of chagasic heart disease. This study included 316 patients with Chagas’ disease and 520 healthy individuals from Colombia and Peru. Genotyping of PTPN22 was performed by the real‐time polymerase chain reaction technology, using the TaqMan 5′ allelic discrimination assay. No statistically significant differences in the frequency of PTPN22 C1858T gene polymorphism between chagasic patients and controls or between asymptomatic and cardiomyopathic individuals were observed. Our findings suggest that the PTPN22 polymorphism analyzed does not play a major role in the development of Chagas’ disease in the Colombian and Peruvian populations.
What would encourage blood donation in Ireland?
Authors: Harrington M. , Sweeney M. R. , Bailie K. , Morris K. , Kennedy A. , Boilson A. , O’Riordan J. , Staines & A. 
Published: February 2007

Background  Recent changes have resulted in the loss of 4% of the donor panel in the Republic of Ireland and 3% in Northern Ireland. In order to increase the number of donors in these two regions, it is important that transfusion service providers explore and understand the reasons, which prevent individuals from donating. The aim of this study was to explore these issues particularly in non‐donors and those who had lapsed.Methods  This 7‐month all‐Ireland study was conducted by computer‐assisted telephone interview. Data collected included sociodemographic history, donation status, as well as barriers/deterrents to donation.Results  There were 4166 completed questionnaires (44% donors; 56% non‐donors). Of the donors, 13% had donated blood within the last 2 years. Current donors cited ‘awareness of patients needs’ (88%), ‘trust in the blood transfusion service’ (70%), and ‘an advertising campaign’ (70%) as reasons encouraging them to donate blood. Lapsed donors and non‐donors cited ‘more frequent mobile clinics/sessions’ (30% lapsed donors; 53% non‐donors), ‘if I was asked’ (28% lapsed donors; 53% non‐donors), and ‘more flexible opening hours’ (23% lapsed donors; 44% non‐donors) as reasons that would encourage them to donate. The main reasons cited by non‐donors for never having donated included ‘medical reasons’ (41% Republic of Ireland; 43% Northern Ireland), ‘lack of information’ (20% Republic of Ireland; 22% Northern Ireland), ‘fear of needles’ (15% Republic of Ireland; 17% Northern Ireland), and ‘time constraints’ (12% Republic of Ireland; 13% Northern Ireland). Among the non‐donor group, 10% (Republic of Ireland) and 6% (Northern Ireland) claimed that they are not permitted to donate.Conclusion  Replacing regular donors is a major challenge for the transfusion service providers. This study shows that by facilitating the general public by introducing more mobile clinics/sessions, more flexible opening hours and having a better level of knowledge in the community about blood donation may encourage lapsed donors and new donors to become regular donors.
Effect of hydroxyurea on sperm count, motility and morphology in adult men with sickle cell or myeloproliferative disease
Authors: Grigg A. 
Published: February 2007

AbstractHydroxyurea (HU) is not infrequently used in patients with sickle cell disease and myeloproliferative disorders. Despite murine data showing adverse effects on sperm counts, motility and morphology, there is little information on the effect of HU on human spermatogenesis. A retrospective review of four adult men who had semen analysis during HU therapy and in three cases after its cessation suggests that HU generally reduces sperm counts and motility and results in abnormal morphology. Cessation of HU in one case with azoospermia resulted in recovery of spermatogenesis; in two of the three cases, however, sperm morphology and mobility remained impaired. Recommendations for fertility management in adult men receiving long‐term HU therapy are proposed.
Urgent liver transplantation for acute liver failure due to parvovirus B19 infection complicated by primary Epstein–Barr virus and cytomegalovirus infections and aplastic anaemia
Authors: So K. , Macquillan G. , Garas G. , Delriviere L. , Mitchell A. , Speers D. , Mews C. , Augustson B. , De Boer W. B. , Baker D. , Jeffrey G. P. 
Published: February 2007

AbstractAn 11‐year‐old boy presented with hepatic failure secondary to parvovirus B19 infection, requiring urgent liver transplantation. His recovery was complicated by primary Epstein–Barr virus and cytomegalovirus infections. He subsequently developed aplastic anaemia that has been refractory to antithymocyte globulin and cyclosporine therapy and may now require bone marrow transplantation. We present this case to emphasize parvovirus as a rare cause of hepatic failure and of aplastic anaemia as a complication of the virus.
Attitudes of medical students to placebo therapy
Authors: Lim E. C.‐H. , Seet R. C. S. 
Published: February 2007

AbstractBackground: Studies have described opposing perceptions of placebo use, with laypersons for and health‐care workers against it. Opinions of medical students have not previously been elicited. This study was based on online electronic survey on beliefs, knowledge and attitudes about placebo therapy, that is, use of placebo in clinical practice, rather than in randomized controlled clinical trials.Methods: The participants were preclinical (years 1, 2) and clinical (years 3–5) medical students. Descriptive analyses and χ2 tests were used to compare the opinions of preclinical and clinical students with statistical significance set at P < 0.05.Results: Four hundred and two (35.6%) out of 1153 students responded, of which 181 were preclinical and 221 were clinical students. Two hundred and eighty‐five (70.9%) students felt that placebo therapy was acceptable and 134 (33.3%) believed that it was beneficial in organic disease. Fifty‐two (12.9%) students felt that it was ethical to prescribe placebo for organic disease with known definitive treatment, 259 (64.4%) for organic disease with no known treatment and 328 (81.6%) for psychogenic disease. More preclinical than clinical students approved of placebo therapy (odds ratio 2.140 (95% confidence interval 1.161–3.944), P = 0.015) and opined that it was ethical to prescribe placebo therapy to organic diseases for which there was appropriate treatment (odds ratio 1.800 (95% confidence interval 0.992–3.266), P = 0.053). A greater number of clinical when compared with preclinical students said that there is evidence that placebo therapy has a beneficial effect on organic disease (odds ratio 2.299 (95% confidence interval 1.468–4.405), P < 0.001).Conclusion: Our medical students felt that placebo therapy is acceptable in certain situations. We identified their erroneous acceptance of placebo therapy in organic diseases, for which there is established treatment, as an area to be addressed in our undergraduate curriculum.
HAUERWAS'S WITH THE GRAIN OF THE UNIVERSE1 AND THE BARTHIAN OUTLOOK: A Few Observations
Authors: Gustavsson Roger 
Published: February 2007

ABSTRACTThis article has two main divisions, the first consisting in parts 1–3, the second in parts 4–8. The purpose of the first division is to assess Hauerwas's contentions regarding what he takes to be serious debilities in modern theological culture. The objects of Hauerwas's criticism are: (1) natural theology; (2) reason as it is represented in the structure of the modern university and in the “Enlightenment Project”; and (3) liberal Protestantism—the latter particularly as it turns up, by his account, in Reinhold Niebuhr's theology. The article will offer a defense of natural theology and an alternative approach to Niebuhr's theology while showing how Hauerwas's contentions concerning these two matters are mistaken. Parts 4–8 are theological studies. These studies concentrate on selected though main aspects of Hauerwas's outlook. Part 4 concerns a problematic implication of the notion, mainly from Barth, of divinity's humanity; Part 5 a note of difficulty from William James about the idea of the theistic God and its pertinence to the Barthian or Hauerwasian God; Part 6 the relation between belief and witness; Part 7 theology's discourse and analogy; Part 8 the Barthian‐Hauerwasian theology as a metaphysics. Part 1, concerning natural theology, stands over both divisions. These observations are not in the main intended as textual studies, though in certain passages the analysis is closely attentive to Hauerwas's text. Also, the paper does not offer the sort of account that would come from a historian, intellectual biographer, or social or cultural analyst or critic. Its focus is philosophical‐theological criticism.
Association between nonmaternal care in the first year of life and children's receptive language skills prior to school entry: the moderating role of socioeconomic status
Authors: Geoffroy Marie‐Claude , Côté Sylvana M. , Borge Anne I.H. , Larouche Frank , Séguin Jean R. , Rutter Michael 
Published: February 2007

Background:  Studies have suggested that nonmaternal care (NMC) may either carry risks or be beneficial for children's language development. However, few tested the possibility that NMC may be more or less protective for children with different family backgrounds. This study investigates the role of the family environment, as reflected in the socioeconomic status (SES), in the association between NMC in the first year of life and children's receptive language skills prior to school entry.Method:  A representative sample of 2,297 Canadian children aged between 0 and 11 months at their first assessment was followed over 4 years. Receptive language skills were assessed with the Peabody Picture Vocabulary Test Revised (PPVT‐R) when the child was 4 to 5 years old.Results:  After controlling for selection factors, SES was found to moderate the association between NMC and receptive language skills: Full‐time NMC in the first year of life was associated with higher PPVT‐R scores among children from low SES families (d = .58), but not among children from adequate SES families.Conclusion:  Full‐time NMC in infancy may contribute to reducing the cognitive inequalities between children of low and adequate SES.