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61.
This case report illustrates the case of a patient who developed recurrent strokes after a pace maker lead was inserted into his left ventricle. It was removed successfully by the cardiothoracic surgeons but he remained very dependent functionally. This case highlights the importance of always reviewing the electrocardiogram and chest radiograph after the insertion of a pacemaker as late diagnosis of this complication can leave the patient with significant morbidity.  相似文献   
62.
Schistosomiasis control programs aim to reduce morbidity but are evaluated by infection prevalence and intensity reduction. We present baseline cross-sectional data from a nested cohort study comparing indicators of morbidity for measuring program impact. Eight hundred twenty-two schoolchildren 7–8 years of age from Nyanza Province, Kenya, contributed stool for diagnosis of Schistosoma mansoni and soil-transmitted helminths (STH) and blood smears for malaria, and were evaluated for anemia, quality of life, exercise tolerance, anthropometry, and ultrasound abnormalities. Schistosoma mansoni, STH, and malaria infection prevalence were 69%, 25%, and 8%, respectively. Only anemia and S. mansoni infection (adjusted odds ratio [aOR] = 1.70; confidence interval [CI] = 1.03–2.80), and hepatomegaly and heavy S. mansoni infection (aOR = 2.21; CI = 1.19–4.11) were associated. Though anemia and hepatomegaly appeared most useful at baseline, additional morbidity indicators may be sensitive longitudinal measures to evaluate schistosomiasis program health impact.  相似文献   
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Using a nontargeted metabolomics approach of 447 fasting plasma metabolites, we searched for novel molecular markers that arise before and after hyperglycemia in a large population-based cohort of 2,204 females (115 type 2 diabetic [T2D] case subjects, 192 individuals with impaired fasting glucose [IFG], and 1,897 control subjects) from TwinsUK. Forty-two metabolites from three major fuel sources (carbohydrates, lipids, and proteins) were found to significantly correlate with T2D after adjusting for multiple testing; of these, 22 were previously reported as associated with T2D or insulin resistance. Fourteen metabolites were found to be associated with IFG. Among the metabolites identified, the branched-chain keto-acid metabolite 3-methyl-2-oxovalerate was the strongest predictive biomarker for IFG after glucose (odds ratio [OR] 1.65 [95% CI 1.39–1.95], P = 8.46 × 10−9) and was moderately heritable (h2 = 0.20). The association was replicated in an independent population (n = 720, OR 1.68 [ 1.34–2.11], P = 6.52 × 10−6) and validated in 189 twins with urine metabolomics taken at the same time as plasma (OR 1.87 [1.27–2.75], P = 1 × 10−3). Results confirm an important role for catabolism of branched-chain amino acids in T2D and IFG. In conclusion, this T2D-IFG biomarker study has surveyed the broadest panel of nontargeted metabolites to date, revealing both novel and known associated metabolites and providing potential novel targets for clinical prediction and a deeper understanding of causal mechanisms.Currently, stratification of individuals at risk for type 2 diabetes (T2D) within the general population is based on well-established factors such as age, BMI, and fasting glucose (1). Although these factors contribute considerably to disease risk, they may not identify at-risk individuals before the disease process is well under way.Recently, a number of studies have found several metabolites to be correlated with insulin resistance and T2D (26), and T2D-associated metabolic profiles have been identified 10–15 years before the diagnosis/onset of the disease (79). To help preventive strategies, and maximize the potential for existing effective interventions, it is important to characterize the molecular changes that take place in the development of T2D.We aim to understand other biochemical changes, in addition to hyperglycemia, that take place at the onset of T2D using the largest metabolomic screening approach to date. We assessed >400 metabolites to determine which metabolomic profiles are correlated with T2D and impaired fasting glucose (IFG) in a large cohort of females from TwinsUK with independent replication.  相似文献   
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There have been considerable advances in the understanding of species concepts in the genus Colletotrichum. This has lead to the need to carry out fresh surveys of Colletotrichum species associated with important hosts. Colletotrichum species are associated with Citrus plants as saprobes, important pre-harvest and post-harvest pathogens, as well as endophytes. In this study, a total of 312 Colletotrichum strains were isolated from leaves, shoots and fruits of cultivated Citrus and Fortunella species with or without disease symptoms across the main citrus production areas in China. The morphology of all strains were studied and multilocus (ACT, TUB2, CAL, GAPDH, GS, ITS) phylogeny established. Strains were from four important species complexes of Colletotrichum, namely C. gloeosporioides species complex, C. boninense species complex, C. acutatum species complex and a final group including C. truncatum, which was rare on Citrus species. The species belonging to the C. gloeosporioides species complex comprised C. gloeosporioides and C. fructicola, the C. boninense complex comprised C. karstii and a new species C. citricola and the C. acutatum complex included a new species, C. citri. The ability of strains to cause anthracnose on citrus fruits was tested by inoculation and strains of Colletotrichum gloeosporioides, C. fructicola and C. truncatum were pathogenic.  相似文献   
68.
Our prior research focused on parental treatment acceptability (TA) and treatment preferences (TPs) for preventive dental treatments for young Hispanic children. We adapted the interview for administration to parents of young African‐American children. Objective: In a sample of African‐American parents, determine parental TA and TP for five dental treatments to prevent early childhood caries. Methods: Interviewed 48 parents/caregivers of African‐American children attending Head Start, assessing TA and TP for three treatments for children: toothbrushing (TB) with fluoride toothpaste, fluoride varnish (FV), and xylitol in food (XF); and two treatments for mothers: xylitol gum (XG) and chlorhexidine (CHX) rinse. The interview included verbal information, illustrated treatment cards, photos/video clips, and samples. Parents provided TA of each treatment (one to five scale), TP between each of 10 pairs of the five treatments, and open‐ended reasons for their preferences. TPs were summed (zero to four) to create overall preference. Results: All treatments were acceptable (means 4.4‐4.9). TB was more acceptable than FV and XF (P < 0.05). Summed TP revealed a strong preference for TB (mean 3.1) above other treatments (all P < 0.01). Primary reasons for preferring TB were the following: promotes healthy habits; child focused; and effectiveness. Conclusions: All treatments were acceptable, however, parents/guardians strongly preferred TB. Parents' emphasis on healthy habits and child‐focused treatment supports efforts for oral health education programs in early childhood settings. Some parents expressed concerns about FV, XF, and CHX. Results may be useful in planning prevention programs for young children in African‐American communities.  相似文献   
69.
The extrapolation to humans of studies of infectious or toxic agents injurious to the respiratory system using animal models assumes comparability in the structure and function of animal models and humans. Measurement of conducting airways and parenchyma yields quantitative data for parameters like volume, surface area, length, cell number and cell size. Over the past few decades, there has been an evolution of rigorous uniform sampling designs of stereology that ensure unbiased estimates of number, length, surface area, and volume. This approach has been termed 'design-based' stereology because of the reliance on sampling design rather than geometric model-based stereology that makes assumptions. The aim of this paper is to define new design-based stereological approaches for the direct estimation of anatomical structures and epithelial, interstitial and endothelial cells of specific regions of the lung independent of the sampling, size, orientation and reference traps. An example is provided using wildtype and transgenic mice expressing transforming growth factor-alpha to show the importance of the reference trap in stereologic estimates of postnatal lung growth.  相似文献   
70.
Characterisation of exogenous folate transport in Plasmodium falciparum   总被引:1,自引:0,他引:1  
Folate salvage by Plasmodium falciparum is an important source of key cofactors, but little is known about the underlying mechanism. Using synchronised parasite cultures, we observed that uptake of this dianionic species against the negative-inward electrochemical gradient is highly dependent upon cell-cycle stage, temperature and pH, but not on mono- or divalent metal ions. Energy dependence was tested with different sugars; glucose was necessary for folate import, although fructose was also able to function in this role, unlike sugars that cannot be processed through the glycolytic pathway. Import into both infected erythrocytes and free parasites was strongly inhibited by the anion-channel blockers probenecid and furosemide, which are likely to be acting predominantly on specific folate transporters in both cases. Import was not affected by high concentrations of the antifolate drugs pyrimethamine and sulfadoxine, but was inhibited by the close folate analogue methotrexate. The pH optimum for folate uptake into infected erythrocytes was 6.5-7.0. Dinitrophenol and nigericin, which strongly facilitate the equilibration of H(+) ions across biological membranes and thus abolish or substantially reduce the proton gradient, inhibited folate uptake profoundly. The ATPase inhibitor concanamycin A also greatly reduced folate uptake, further demonstrating a link to ATP-powered proton transport. These data strongly suggest that the principal folate uptake pathway in P. falciparum is specific, highly regulated, dependent upon the proton gradient across the parasite plasma membrane, and is likely to be mediated by one or more proton symporters.  相似文献   
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