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International Journal of Clinical Pharmacy - Background Drug-related problems are relatively common among hospitalised patients and may be detrimental to patients and even increase healthcare...  相似文献   
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Molecular Imaging and Biology - Aberrantly expressed glycans in cancer are of particular interest for tumor targeting. This proof-of-concept in vivo study aims to validate the use of aberrant Lewis...  相似文献   
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Diabetes is a chronic disease that is characterized by an increased blood glucose level due to insulin resistance. Type 2 diabetes is common in middle aged and old people. In this work, we present a technique to analyze dynamic foot pressures images and classify them into normal, diabetes type 2 with and without neuropathy classes. Plantar pressure images were obtained using the F-Scan (Tekscan, USA) in-shoe measurement system. We used Principal Component Analysis (PCA) and extracted the eigenvalues from different regions of the foot image. The features extracted from region 1 of the foot pressure image, which were found to be clinically significant, were fed into the Fuzzy classifier (Sugeno model) for automatic classification. Our results show that the proposed method is able to identify the unknown class with an accuracy of 93.7%, sensitivity of 100%, and specificity of 83.3%. Moreover, in this work, we have proposed an integrated index using the eigenvalues to differentiate the normal subjects from diabetes with and without neuropathy subjects using just one number. This index will help the clinicians in easy and objective daily screening, and it can also be used as an adjunct tool to cross check their diagnosis.  相似文献   
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Udupa  KB; Lipschitz  DA 《Blood》1982,59(6):1267-1271
The regulation of erythropoiesis is primarily controlled by erythropoietin (Ep). Recently, however, other factors that both stimulate and inhibit erythropoiesis have been reported. Using an in vitro liquid culture of bone marrow cells, a factor in normal mouse serum was demonstrated that markedly stimulated heme synthesis by marrow erythroid cells. In this study, the role of this heme synthesis stimulating factor (HSF) and Ep in the erythropoietic suppression caused by endotoxin administration to mice was examined. Although HSF levels did not alter appreciably after endotoxin injection, marrow erythroid cells from these animals became unresponsive to the factor. This could be reversed if Ep was added to the culture in vitro or if the hormone was injected into the mice 18 hr prior to harvesting the marrow. This marrow erythroid cell response is identical to that seen in animals in whom Ep levels are markedly reduced, such as that found in exhypoxic polycythemia, and suggest a decrease in the hormone following endotoxin administration. Additional studies demonstrated that when Ep was injected into mice 6 hr after endotoxin administration, an increase in femoral erythroid colony-forming units (CFU-E), proerythroblast number, and 59 Fe incorporation into femoral marrow cells could be demonstrated. These findings, together with the marrow erythroid cell response to the hormone, suggest that the mechanism for suppression of erythropoiesis after endotoxin injection is a reduction in the level of circulating Ep.  相似文献   
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Burkholderia pseudomallei (Bp) is the causative agent of the infectious disease melioidosis. To investigate population diversity, recombination, and horizontal gene transfer in closely related Bp isolates, we performed whole-genome sequencing (WGS) on 106 clinical, animal, and environmental strains from a restricted Asian locale. Whole-genome phylogenies resolved multiple genomic clades of Bp, largely congruent with multilocus sequence typing (MLST). We discovered widespread recombination in the Bp core genome, involving hundreds of regions associated with multiple haplotypes. Highly recombinant regions exhibited functional enrichments that may contribute to virulence. We observed clade-specific patterns of recombination and accessory gene exchange, and provide evidence that this is likely due to ongoing recombination between clade members. Reciprocally, interclade exchanges were rarely observed, suggesting mechanisms restricting gene flow between clades. Interrogation of accessory elements revealed that each clade harbored a distinct complement of restriction-modification (RM) systems, predicted to cause clade-specific patterns of DNA methylation. Using methylome sequencing, we confirmed that representative strains from separate clades indeed exhibit distinct methylation profiles. Finally, using an E. coli system, we demonstrate that Bp RM systems can inhibit uptake of non-self DNA. Our data suggest that RM systems borne on mobile elements, besides preventing foreign DNA invasion, may also contribute to limiting exchanges of genetic material between individuals of the same species. Genomic clades may thus represent functional units of genetic isolation in Bp, modulating intraspecies genetic diversity.Burkholderia pseudomallei (Bp) is the causative agent of melioidosis, a serious infectious disease of humans and animals and a leading cause of community-acquired sepsis and pneumonia in endemic regions (Currie et al. 2010). Initially thought to be confined to Southeast Asia and Northern Australia, the prevalence of Bp appears to be spreading (Wiersinga et al. 2012), and Bp has been designated a biothreat select agent in the United States. Bp can persist in extreme environmental conditions and can infect several plant and animal hosts, including birds, dolphins, and humans (Wuthiekanun et al. 1995; Howard and Inglis 2003; Sprague and Neubauer 2004; Larsen et al. 2013). Treatment of clinical melioidosis is challenging because the bacterium is inherently resistant to many antibiotics, and Bp infections can persist in humans for more than a decade (Hayden et al. 2012; Wiersinga et al. 2012).The Bp genome comprises one of the largest and most complex bacterial genomes sequenced to date. Consisting of two large circular replicons (chromosomes) with a combined 7.2-Mb genome size (Holden et al. 2004), it contains a rich arsenal of genes related to virulence (e.g., Type III and Type VI secretion systems, polysaccharide biosynthesis clusters), metabolic pathways, and environmental adaptation (Wiersinga et al. 2012). Besides conserved regions, accessory genes on mobile elements and genomic islands may also contribute to phenotypic and clinical differences in microbial behavior (Currie et al. 2000; Sim et al. 2008). Analysis of the Bp genome has revealed previously unknown toxins and mechanisms of antibiotic resistance (Chantratita et al. 2011; Cruz-Migoni et al. 2011).Most large-scale studies of Bp genetic diversity to date have analyzed strains using multilocus sequence typing (MLST). These studies have suggested a high degree of genetic variability between Bp strains and related Burkholderia species (Cheng et al. 2008), and have shown that Bp strains belonging to different sequence types (STs) can often coexist in the same locale and sometimes even within the same sample (Pitt et al. 2007; Wuthiekanun et al. 2009). However, due to the limited number of genes analyzed by MLST, these studies cannot comment on the global proportion of genetic material shared between strains of different STs nor on the relative contribution of recombination, mutation, and horizontal gene transfer on intraspecies genetic diversity. Moreover, although previous studies have applied whole-genome sequencing (WGS) to study global patterns of Bp genetic heterogeneity and evolution, earlier Bp WGS reports have been confined to a limited number of isolates (10–12) derived from diverse geographical regions (Nandi et al. 2010), where geophysical barriers likely limit the propensity of the analyzed strains to exchange genetic material. To achieve a comprehensive understanding of genetic variation among closely related Bp strains, WGS analysis of much larger strain panels, ideally performed on strains isolated from a common region and belonging to the same (or closely related) ST groups, is required.In this study, we attempted to fill this important knowledge gap by performing WGS on 106 Bp strains drawn from a restricted Asian locale (Singapore and Malaysia). The WGS data, exceeding previous Bp WGS studies by 10-fold, enabled us to identify specific genomic clades of Bp, molecular features of Bp recombination at the whole-genome level, and accessory genome features contributing to recombination and horizontal gene transfer. We found a consistent pattern of genetic separation correlating with MLST, recombination haplotypes, shared accessory genes, and restriction modification (RM) systems. We provide evidence that restriction modification, beyond its role as defense against foreign DNA invasion, may have also partitioned the Bp species by restricting gene flow, resulting in the other observed correlations. Because RM systems are widely dispersed through the bacterial kingdom, it is possible that similar principles may apply to other bacterial species, implicating a potential role for epigenetic barriers as a driver of early incipient speciation.  相似文献   
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