bluuebunny/crossref_metadata_2025_split huggingface dataset:
Central nervous system capillary haemangioblastoma: the pathologist's viewpoint
Authors: Hussein Mahmoud R. 
Published: May 2007

SummaryHaemangioblastomas are rare neoplasms of uncertain histogenesis. They represent 1.5–2.5% of intracranial tumours. While the cerebellum is by far the most frequent site, these lesions also tend to occur in the medulla and spinal cord. Most haemangioblastomas are sporadic but up to one quarter are associated with Von Hippel–Lindau disease (VHL). Although a fairly good number of haemangioblastomas were reported, a lack of side‐by‐side analysis of these reports has resulted in tentative conclusions that merely offer a first glimpse at their clinicopathologic diversity and histogenesis. To remedy this issue, this study presents a literature review concerning these lesions. Medline literature including both relevant monographs and clinicopathological case series. Haemangioblastomas occur either as a part of VHL disease (25–30%, inherited mutation of VHL gene on 3p25–26 chromosome) or as sporadic tumours (often with somatic mutation of VHL gene). They have diverse clinicopathologic presentations with cerebellar lesions having a better prognosis than their brainstem counterparts. Immunostaining is important for separation of haemangioblastomas from other tumours with similar histology. The rich vascularity of haemangioblastomas is due to overexpression of vascular endothelial growth factors. Moreover, ‘stromal’ cells represent the neoplastic cells of haemangioblastomas and are capable of forming blood islands with extramedullary haematopoiesis.
Subterranean rodents of the genusCtenomys(Caviomorpha, Ctenomyidae) follow the converse to Bergmann's rule
Authors: Medina Alonso I. , Martí Dardo A. , Bidau Claudio J. 
Published: May 2007

AbstractAim We analysed body‐size variation in relation to latitude, longitude, elevation and environmental variables inCtenomys(tuco‐tucos), subterranean rodents in the Ctenomyidae (Caviomorpha). We tested the existence of inter‐ and intraspecific size clines to determine if these rodents follow Bergmann's rule, to compare intra‐ and interspecific size trends and to assess the relevance of the subterranean lifestyle on these trends.Location South America, south of 15° latitude.Methods This paper is based on 719 specimens of tuco‐tucos from 133 localities of Argentina, Bolivia, Chile, Paraguay, Peru and Uruguay, representing 47 named species and 32 undescribed forms. Intraspecific analyses were performed forCtenomys talarumThomas, 1898 and theCtenomys perrensiThomas, 1896 species complex. Head and body length and weight were used for estimating body size. Geographical independent variables included latitude, longitude and altitude. Environmental independent variables were mean minimal and maximal monthly temperature, mean annual temperature, mean minimal and maximal precipitation, and total annual precipitation. To estimate seasonality, the annual variability of the climatic factors was calculated as their coefficients of variation and the difference between maximum and minimum values. Mean annual actual evapotranspiration (AET), and mean annual, January (summer) and July (winter) potential evapotranspiration (PET) values were also calculated for each locality, as well as annual, summer and winter water balance (WB). Statistical analyses consisted of simple and multiple regression and nonparametric correlation.Results Body size ofCtenomysdecreases interspecifically from 15°00′ S to 48°15′ S and from 56°33′ W to 71°46′ W, and is positively correlated with ambient temperature and precipitation. The best predictors of body size according to multiple regression analyses were mean annual temperature, the difference between mean maximum and minimum annual temperatures, annual PET, the difference between summer and winter PET, and annual and winter water balance. These patterns are repeated, but not identically, at a smaller geographical scale within the speciesC. talarumand the superspeciesC. perrensi.Main conclusions Tuco‐tucos follow the converse to Bergmann's rule at the interspecific level. At the intraspecific level some parallel trends were observed, but the smaller scale of these analyses, involving a very reduced variation of environmental factors, necessitates caution in interpreting results. The subterranean lifestyle probably insulates these rodents from the external temperature. The observed latitudinal body‐size gradients are more probably related to seasonality, ambient energy, primary productivity and/or intensity of predation.
Geographical distribution and extinction risk: lessons from Triassic–Jurassic marine benthic organisms
Authors: Kiessling Wolfgang , Aberhan Martin 
Published: May 2007

AbstractAim To evaluate the influence of geographical distribution on the extinction risk of benthic marine invertebrates using data from the fossil record, both during times of background extinction and across a mass‐extinction episode. Total geographical range is contrasted with proxies of global abundance to assess the relationships between the two essential components of geographical distribution and extinction risk.Location A global occurrence data base of fossil benthic macro‐organisms from the Triassic and Jurassic periods was used for this study.Methods Geographical distributions and biodiversity dynamics were assessed for each genus (all taxa) or species (bivalves) based on a sample‐standardized data set and palaeogeographical reconstructions. Geographical ranges were measured by the maximum great circle distance of a taxon within a stratigraphic interval. Global abundance was assessed by the number of localities at which a taxon was recorded. Widespread and rare taxa were separated using median and percentile values of the frequency distributions of occurrences.Results The frequency distribution of geographical ranges is very similar to that for modern taxa. Although no significant correlation could be established between local abundance and geographical range, proxies of global abundance are strongly correlated with geographical range. Taxon longevities are correlated with both mean geographical range and mean global abundance, but range size appears to be more critical than abundance in determining extinction risk. These results are valid when geographical distribution is treated as a trait of taxa and when assessed for individual geological stages.Main conclusions Geographical distribution is a key predictor of extinction risk of Triassic and Jurassic benthic marine invertebrates. An important exception is in the end‐Triassic mass extinction, which equally affected geographically restricted and widespread genera, as well as common and rare genera. This suggests that global diversity crises may curtail the role of geographical distribution in determining extinction risk.
Local–regional boundary shifts in oribatid mite (Acari: Oribatida) communities: species–area relationships in arboreal habitat islands of a coastal temperate rain forest, Vancouver Island, Canada
Authors: Lindo Zoë , Winchester Neville N. 
Published: May 2007

AbstractAim This study investigates the species–area relationship (SAR) for oribatid mite communities of isolated suspended soil habitats, and compares the shape and slope of the SAR with a nested data set collected over three spatial scales (core, patch and tree level). We investigate whether scale dependence is exhibited in the nested sampling design, use multivariate regression models to elucidate factors affecting richness and abundance patterns, and ask whether the community composition of oribatid mites changes in suspended soil patches of different sizes.Location Walbran Valley, Vancouver Island, Canada.Methods A total of 216 core samples were collected from 72 small, medium and large isolated suspended soil habitats in six western redcedar trees in June 2005. The relationship between oribatid species richness and habitat volume was modelled for suspended soil habitat isolates (type 3) and a nested sampling design (type 1) over multiple spatial scales. Nonlinear estimation parameterized linear, power and Weibull function regression models for both SAR designs, and these were assessed for best fit usingR2and Akaike's information criteria (ΔAIC) values. Factors affecting oribatid mite species richness and standardized abundance (number per g dry weight) were analysed byanovaand linear regression models.Results Sixty‐seven species of oribatid mites were identified from 9064 adult specimens. Surface area and moisture content of suspended soils contributed to the variation in species richness, while overall oribatid mite abundance was explained by moisture and depth. A power‐law function best described the isolate SAR (S = 3.97 × A0.12,R2 = 0.247,F1,70 = 22.450,P < 0.001), although linear and Weibull functions were also valid models. Oribatid mite species richness in nested samples closely fitted a power‐law model (S = 1.96 × A0.39,R2 = 0.854,F1,18 = 2693.6,P < 0.001). The nested SAR constructed over spatial scales of core, patch and tree levels proved to be scale‐independent.Main conclusions Unique microhabitats provided by well developed suspended soil accumulations are a habitat template responsible for the diversity of canopy oribatid mites. Species–area relationships of isolate vs. nested species richness data differed in the rate of accumulation of species with increased area. We suggest that colonization history, stability of suspended soil environments, and structural habitat complexity at local and regional scales are major determinants of arboreal oribatid mite species richness.
Intra‐seasonal precipitation patterns and above‐ground productivity in three perennial grasslands
Authors: SWEMMER ANTHONY M. , KNAPP ALAN K. , SNYMAN HENNIE A. 
Published: May 2007

Summary

Relationships between above‐ground net primary productivity (ANPP) of grasslands and annual precipitation are often weak at the site level, with much of the inter‐annual variation in ANPP left unexplained. A potential reason for this is that the distribution of precipitation within a growing season affects productivity in addition to the total amount.
We analysed long‐term ANPP data for three southern African temperate grasslands (mean annual precipitation ranging from 538 mm to 798 mm) to determine the effects of precipitation event size, number and spacing relative to seasonal totals.
Ungrazed, non‐manipulated treatments at each site showed contrasting results despite sharing a common, dominant species. At the driest site, a model combining average event size and number of events per growing season provided a substantially better fit to the ANPP data than precipitation amount (seasonal total). At the wettest site, the interval between events was the most important precipitation variable. Precipitation distribution was not important at the intermediate site where amount was the best predictor of ANPP. A limit to the size of precipitation events efficiently utilized for ANPP was evident for the driest site only.
At each site, experimental treatments that altered species composition and soil fertility had little effect on precipitation–ANPP relationships. The lack of consistency in the relative importance of the precipitation variables among sites suggests that local, edaphic factors modify precipitation–ANPP relationships.
This analysis demonstrates that the distribution and size of precipitation events can affect ANPP independent of precipitation amount. As altered precipitation regimes are forecast by global climate models, the sensitivity of ecosystems to precipitation distribution should be considered when predicting responses to climate change.
While mean values of precipitation, and other ecosystem drivers, are typically used to predict function at the level of whole ecosystems, our results show that more complex measures of environmental variability may be required to understand ecosystem function, and to increase the accuracy of predictions of ecosystem responses to global change.
Aiolos Controls Gene Conversion and Cell Death in DT40 B Cells
Authors: Narvi E. , Nera K.‐P. , Terho P. , Mustonen L. , Granberg J. , Lassila O. 
Published: May 2007

AbstractThe Ikaros family transcription factor Aiolos is important for B cell function, since B cells of Aiolos‐null mutant mice exhibit an activated phenotype, enhanced B‐cell receptor (BCR) signalling response and develop a systemic lupus erythematosus (SLE) type autoimmune disease. Aiolos has also been reported to interact with anti‐apoptotic Bcl‐2 and Bcl‐xL in T cells, but whether Aiolos regulates cell death has not been studied in B cells. Here we show that the disruption of Aiolos in the DT40 B cell line induces a cell death sensitive phenotype, as the Aiolos−/− cells are more prone to apoptosis by nutritional stress, BCR cross‐linking, UV‐ or γ‐irradiation. Furthermore, the Aiolos−/− cells have defective Ig gene conversion providing evidence that Aiolos is needed for the somatic diversification of the BCR repertoire. The re‐expression of DNA‐binding isoform Aio‐1 was able to restore the gene conversion defect of the Aiolos‐deficient cells, whereas the introduction of dominant negative isofom Aio‐2 had no effect on gene conversion, thus demonstrating the functional importance of alternative splicing within Ikaros family. Although the Aiolos−/− cells exhibit reduced expression of activation‐induced cytidine deaminase (AID), ectopic AID overexpression did not restore the gene conversion defect in the Aiolos−/− cells. Our findings indicate that Aiolos may regulate gene conversion in an AID independent manner.
A Dual Altered Peptide Ligand Inhibits Myasthenia Gravis Associated Responses by Inducing Phosphorylated Extracellular‐regulated Kinase 1,2 that Upregulates CD4+CD25+Foxp3+ Cells
Authors: Ben‐David H. , Venkata Aruna B. , Sela M. , Mozes E. 
Published: May 2007

AbstractMyasthenia gravis (MG) and its animal model experimental autoimmune MG (EAMG), are T‐cell dependent, antibody‐mediated autoimmune disorders. A dual altered peptide ligand (APL) composed of the tandemly arranged two single amino acids analogs of two myasthenogenic peptides, p195–212 and p259–271, was demonstrated to downregulate, in vitro and in vivo, MG‐associated autoimmune responses. Upregulation of regulatory CD4+CD25+ cells plays a key role in the mechanism of action of the dual APL. The objectives of the present study were to address the involvement of extracellular‐regulated kinase (ERK)1,2 in the mechanisms by which the dual APL‐induced CD4+CD25+ cells suppress MG‐associated autoimmune responses. We demonstrate here that administration of the dual APL increased activated ERK1,2 in the CD4+CD25+‐enriched population. Further, inhibition of ERK1,2 by its inhibitor, U0126, in dual APL‐induced CD4+CD25+ cells, abrogated their ability to suppress interferon (IFN)‐γ secretion by lymph node (LN) cells of mice that were immunized with the myasthenogenic peptide. Moreover, inhibition of ERK1,2 in the dual APL‐induced regulatory CD4+CD25+ cells, resulted in downregulation of the forkhead box p3 (Foxp3) gene and protein expression levels, as well as in the downregulation of CD4+CD25+ development, suggesting that the active suppression exerted by the dual APL via CD4+CD25+ cells depends on ERK1,2 activity.
Protective Acquired Immunity to Enteromyxum scophthalmi (Myxozoa) is Related to Specific Antibodies in Psetta maxima (L.) (Teleostei)
Authors: Sitjà‐Bobadilla A. , Palenzuela O. , Riaza A. , Macías M. A. , Alvarez‐Pellitero P. 
Published: May 2007

AbstractThe acquired protection of three groups of turbot that had survived enteromyxosis outbreaks was tested by challenging with E. scophthalmi in three different experiments. The relation of such a response with the kinetics and duration of antibody production (determined by an ELISA) was studied. The progression of the infection was evaluated by PCR. In experiments 1 and 2, in which turbot had cohabited with highly infected fish during outbreaks, parasite prevalence and mortality were very low or null, and there was a progressive and statistically significant increase in the mean antibody production up to 350 and 152 days post‐exposure respectively. By contrast, in experiment 3, fish (coming from non‐infected tanks during the initial outbreak), both infection prevalence and cumulative mortality reached 92.8%, and specific antibodies were detected only in two fish. The observed differences in mortality after challenge appear to be related to the production of specific antibodies and it is probably accompanied by a repertoire of mechanisms of innate immunity. The exploitation of the immune system through breeding selection programmes as a possible strategy to control the disease is discussed.
Annular atrophic lichen planus
Authors: Ponce‐Olivera Rosa María , Tirado‐Sánchez Andrés , Montes‐de‐Oca‐Sánchez Griselda , León‐Dorantes Gladys , Mercadillo‐Pérez Patricia 
Published: May 2007

A 30‐year‐old woman presented with a 1‐year history of a pruritic eruption on the extremities, characterized by several annular plaques. The patient had been treated unsuccessfully with medium‐potency topical steroids. The lesions had an erythematous papular border with an atrophic center (width, 1–4 cm) (Fig. 1). No oral, genital, or nail lesions were observed.Annular lesion with an infiltrated border and atrophic centerimageA skin biopsy from one of the plaques was performed. Histopathologic examination of the raised border showed hyperkeratosis of the stratum corneum, focal thickening of the granular layer, basal liquefaction degeneration of the epidermis, and a band‐like subepidermal infiltration with numerous Civatte bodies. In the center of the lesion, the epidermis became thinner (Fig. 2). Elastic fibers were reduced or absent in the papillary dermis.(a) Biopsy of the border of a plaque with the typical changes of lichen planus (hematoxylin and eosin, ×10), with flattened epidermis in the center of the plaque; (b) medium power of the border of the plaque with details of the changes of lichen planus (hematoxylin and eosin, ×40)imageThe patient was treated with high‐potency topical steroids for 2 months with clinical improvement.
Comparative study of fig tree efficacy in the treatment of common warts (Verruca vulgaris) vs. cryotherapy
Authors: Bohlooli Shahab , Mohebipoor Alireza , Mohammadi Sadollah , Kouhnavard Mina , Pashapoor Sedigheh 
Published: May 2007

AbstractBackground  A traditional method for the treatment of warts in some rural areas of Iran comprises the use of fig tree (ficus carica) latex as a local treatment; however, there is no scientific evaluation of its efficacy.Methods  A prospective, open right/left comparative trial of fig tree latex therapy vs. local standard of cryotherapy was carried out. Twenty‐five patients with common warts were recruited into the study from an outpatient clinic. The patients were instructed in self‐application of fig tree latex to warts on one side of the body. The wart on the opposite side was treated using standard cryotherapy. A 6‐month follow‐up study was planned.Results  In 11 (44%) of the 25 patients complete resolution of fig tree latex‐treated warts was observed. The remaining 14 patients (56%) had a complete cure following cryotherapy. Two patients had complete remission on both sides. Two patients failed to respond to either cryotherapy or fig tree latex. It was found that fig tree latex therapy was marginally less effective than cryotherapy. Adverse effects were observed only in cryo‐treated warts. At the 6‐month follow‐up study there was an 18% recurrence rate.Conclusion  Fig tree latex therapy of warts offers several beneficial effects including short‐duration therapy, no reports of any side‐effects, ease‐of‐use, patient compliance, and a low recurrence rate. The exact mechanism of the antiwart activity of fig tree latex is unclear but is likely to be the result of the proteolytic activity of the latex enzymes.
Differences in psychosocial profiles between men and women living kidney donors
Authors: Achille Marie , Soos John , Fortin Marie‐Chantal , Pâquet Michel , Hébert Marie‐Josée 
Published: May 2007

Abstract:  Background:  The expansion of kidney transplantation by living donation has led to a disproportional increase in the women to men ratio among donors and this difference cannot be explained on the basis of medical exclusion. The present study was designed to test whether women donors are more likely to (i) display altruistic and gender‐typed nurturing behaviour and (ii) be subtly influenced by family pressure to donate and less able to resist this pressure.Methods:  All 71 (61% women) individuals who had donated a kidney at our centre between 1995 and 2005 were sent a survey. Thirty‐nine individuals (71% response rate; 64% female participation) filled out and returned the survey, which included standardized measures of altruism, self‐esteem, family dynamics and endorsement of gender‐stereotyped roles, as well as sociodemographic questions and questions about donation.Results:  Findings show no difference between women and men in terms of the psychological attributes measured. One woman and two men reported having felt pressure to donate, and 92% of women compared with 54% of men reported having felt free to change their mind. Men took longer than women to make the decision to donate.Conclusions:  Results suggest that among individuals who have already donated, there is no evidence that women may be more inclined to donate than man because of differences in their psychosocial profiles or because they may be more vulnerable to family pressure. Future research may gain from focusing on men and women donors and non‐donors in families where transplantation is being considered.
Macrophage migration inhibitory factor gene influences the risk of developing tuberculosis in northwestern Colombian population
Authors: Gómez L. M. , Sánchez E. , Ruiz‐Narvaez E. A. , López‐Nevot M. A. , Anaya J.‐M. , Martín J. 
Published: May 2007

AbstractMacrophage migration inhibitory factor (MIF) is a pleiotropic cytokine that regulates innate and adaptative immunity responses against pathogens. The MIF gene, at 22q11.2, is polymorphic. Functional promoter variants in the MIF gene influence susceptibility to inflammatory diseases in Caucasians and Africans. An association study was carried out to examine the influence of MIF−173 single nucleotide polymorphism and the MIF−794 microsatellite on the susceptibility to develop human tuberculosis (TB) in a well‐defined Latin‐American population. To this purpose, 230 northwestern Colombian patients with pulmonary TB, negative for human immunodeficiency virus infection, and 235 matched healthy individuals stratified by the tuberculin skin test were examined. Multivariate analysis showed that MIF−173C allele was associated with disease (odds ratio = 1.64, 95% confidence interval 1.07–2.52) in a dominant pattern. No allele in the MIF−794 CATT microsatellite was associated with risk of TB. These results indicate that MIF gene influences the risk of developing TB in the studied population.