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51.
Untreated tuberculosis during pregnancy presents a serious risk for transmission of disease to the newborn and can result in adverse perinatal and obstetrical outcomes. Tuberculosis during pregnancy and congenital tuberculosis are infrequent conditions and are difficult to diagnose due the non-specificity of the symptoms. A case report is presented of a woman who had no children previously with disseminated miliary tuberculosis. Tuberculosis symptoms appeared immediately after birth of the first child, with a clinical diagnosis on the second month after childbirth, whereupon the patient died. The son, a premature infant, showed disease symptoms from the first day, with primary pulmonary complex and persistent atelectasis due to bronchial obstruction. The obstruction was due to thoracic lymphadenitis and coinfection with cytomegalovirus. The infant received standard treatment and his condition improved. 相似文献
52.
Congruence between floristic patterns of trees and lianas in a southwest Amazonian rain forest 总被引:1,自引:0,他引:1
Manuel J. Macía Kalle Ruokolainen Hanna Tuomisto Javier Quisbert Victoria Cala 《Ecography》2007,30(4):561-577
The congruence in floristic patterns between different life-forms of woody plants remains poorly understood in tropical rain forests. We explored whether the floristic patterns of woody plants, divided into small trees 2.5–10 cm dbh, large trees ≥10 cm dbh, and lianas ≥2.5 cm dbh were associated with each other or with patterns in soil properties, elevation, and geographical distances between sample plots. We also tested whether ecological amplitudes in relation to environmental variables differed among the plant groups. Trees and lianas were inventoried in 44 0.1-ha plots, distributed among three lowland and two submontane sites in the Madidi National Park, Bolivia. Soil samples were analysed for physico-chemical properties. Floristic differences between sites (as measured with each plant group separately) yielded significant Mantel correlations with each other, and with pH, Ca, Mg, elevation and geographical distance. Mantel correlations with edaphic distances were higher for large trees than small trees, but for Mantel correlations with geographical distance the situation was reversed. Environmental and geographical distances explained 31% of the variation in floristic differences for large trees, 22% for small trees, and 10% for lianas. The ecological amplitudes of lianas were wider than those of all trees for pH, Mg and elevation. The amplitudes of the two size classes of trees did not differ. In principal coordinates ordination, the three plant groups produced similar overall floristic patterns that were explainable by environmental factors. 相似文献
53.
Erik JM Toonen Pilar Barrera Jaap Fransen Arjan PM de Brouwer Agnes M Eijsbouts Pierre Miossec Hubert Marotte Hans Scheffer Piet LCM van Riel Barbara Franke Marieke JH Coenen 《Arthritis research & therapy》2012,14(6):R264
Introduction
The goal of this study is to investigate whether the -308G > A promoter polymorphism in the tumor necrosis factor alpha (TNFA) gene is associated with disease severity and radiologic joint damage in a large cohort of patients with rheumatoid arthritis (RA).Methods
A long-term observational early RA inception cohort (n = 208) with detailed information about disease activity and radiologic damage after 3, 6 and 9 years of disease was genotyped for the TNFA -308G > A promoter polymorphism (rs1800629). A longitudinal regression analysis was performed to assess the effect of genotype on RA disease severity and joint damage. Subsequently, a meta-analysis, including all publically available data, was performed to further test the association between joint erosions and the TNFA polymorphism. To learn more about the mechanism behind the effect of the polymorphism, RNA isolated from peripheral blood from RA patients (n = 66) was used for TNFA gene expression analysis by quantitative PCR.Results
Longitudinal regression analysis with correction for gender and disease activity showed a significant difference in total joint damage between GG and GA+AA genotype groups (P = 0.002), which was stable over time. The meta-analysis, which included 2,053 patients, confirmed an association of the genetic variant with the development of erosions (odds ratio 0.78, 95% CI 0.62, 0.98). No significant differences in TNFA gene expression were observed for the different genotypes, confirming earlier findings in healthy individuals.Conclusions
Our data confirm that the TNFA -308G > A promoter polymorphism is associated with joint damage in patients with RA. This is not mediated by differences in TNFA gene expression between genotypes. 相似文献54.
Models of rheumatoid arthritis (RA) in laboratory animals are important tools for research into pathogenic mechanisms and
the development of effective, safe therapies. Rodent models (rats and mice) have provided important information about the
pathogenic mechanisms. However, the evolutionary distance between rodents and humans hampers the translation of scientific
principles into effective therapies. The impact of the genetic distance between the species is especially seen with treatments
based on biological molecules, which are usually species-specific. The outbred nature and the closer anatomical, genetic,
microbiological, physiological, and immunological similarity of nonhuman primates to humans may help to bridge the wide gap
between inbred rodent strain models and the heterogeneous RA patient population. Here we review clinical, immunological and
pathological aspects of the rhesus monkey model of collagen-induced arthritis, which has emerged as a reproducible model of
human RA in nonhuman primates. 相似文献
55.
Calsequestrin (CSQ) concentrates in junctional sarcoplasmic reticulum (SR) where it functions in regulation of Ca2+ release. When purified from heart tissue, cardiac CSQ contains phosphate on a cluster of C-terminal serine residues, but little is known about the cellular site of kinase action, and the identity of the kinase remains uncertain. To determine basic features of the phosphorylation, we examined the reaction in canine heart preparations. CSQ phosphorylation was observed in [32P]metabolically-labeled heart cells after adenoviral overexpression, and its constitutive phosphorylation was limited to a CK2-sensitive C-terminal serine cluster. The CSQ kinase was oriented intralumenally, as was CSQ, inside membrane vesicles, such that exposure to each required detergent permeabilization. Yet even after detergent permeabilization, CSQ was phosphorylated much less efficiently by protein kinase CK2 in cardiac microsomes than was purified CSQ. Reduced phosphorylation was strongly dependent upon protein concentration, and phosphorylation time courses revealed a phosphatase activity that occurred constitutively as phosphorylated substrate accumulates. Evidence of selective dephosphorylation of CSQ glycoforms in heart homogenates was also seen by mass spectrometry analysis. Molecules with greater mannose content, a feature of early secretory pathway compartments, were more highly phosphorylated, while greater dephosphorylation was apparent in more distal compartments. Taken together, the analyses of CSQ phosphorylation in heart suggest that a constitutive process of phosphate turnover occurs for cardiac CSQ perhaps associated with its intracellular transport. 相似文献
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The reciprocal position of sexual organs in complementary floral morphs is central to our understanding of heterostyly. Reciprocity indices are used to quantify the spatial match between complementary sex organs, but previous indices fail to appropriately account for intra-population variation in sex organ positions. In this study, we examine how an increase in intra-population variation in sex organ heights affects reciprocity and consequently reproductive success. We formulated a reciprocity index that incorporates this variation and asked if estimates of reciprocity can predict reproductive success in naturally occurring heterostylous populations. We developed a reciprocity index that assumed pollen transfer success equalled one for a perfectly matched stigma–anther pair, and decreased to zero with increasing mismatch. We examined the relationship between intra-population variation in organ position and reciprocity, compared previously proposed indices using simulated populations and empirical data from natural populations, and tested the ability of the indices to predict reproductive success. We observed that when differences between mean complementary sex-organ heights are small, increasing intra-population variation in heights resulted in a decrease in reciprocity. However, when this difference is larger, reciprocity increased, reached a peak, and then decreased with increasing variation. Previous indices failed to capture this behavior. Seed set was positively related to reciprocity for our index. These results challenge the current understanding that increasing variation in sex-organ heights will always decrease reciprocity in heterostylous populations. This may help explain why heterostylous systems exhibit and tolerate high amounts of intra-population variation in sex organ heights. 相似文献
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