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91.
Detection and characterization of placental microRNAs in maternal plasma   总被引:4,自引:0,他引:4  
BACKGROUND: The discovery of circulating fetal nucleic acids in maternal plasma has opened up new possibilities for noninvasive prenatal diagnosis. MicroRNAs (miRNAs), a class of small RNAs, have been intensely investigated recently because of their important regulatory role in gene expression. Because nucleic acids of placental origin are released into maternal plasma, we hypothesized that miRNAs produced by the placenta would also be released into maternal plasma. METHODS: We systematically searched for placental miRNAs in maternal plasma to identify miRNAs that were at high concentrations in placentas compared with maternal blood cells and then investigated the stability and filterability of this novel class of pregnancy-associated markers in maternal plasma. RESULTS: In a panel of TaqMan MicroRNA Assays available for 157 well-established miRNAs, 17 occurred at concentrations >10-fold higher in the placentas than in maternal blood cells and were undetectable in postdelivery maternal plasma. The 4 most abundant of these placental miRNAs (miR-141, miR-149, miR-299-5p, and miR-135b) were detectable in maternal plasma during pregnancy and showed reduced detection rates in postdelivery plasma. The plasma concentration of miR-141 increased as pregnancy progressed into the third trimester. Compared with mRNA encoded by CSH1 [chorionic somatomammotropin hormone 1 (placental lactogen)], miR-141 was even more stable in maternal plasma, and its concentration did not decrease after filtration. CONCLUSION: We have demonstrated the existence of placental miRNAs in maternal plasma and provide some information on their stability and physical nature. These findings open up a new class of molecular markers for pregnancy monitoring.  相似文献   
92.
Neisseria gonorrhoeae infections have been empirically treated in Hong Kong with a single oral 400-mg dose of ceftibuten since 1997. Following anecdotal reports of the treatment failure of gonorrhea with oral extended-spectrum cephalosporins, the current study was undertaken to determine the antimicrobial susceptibility pattern and molecular characteristics of isolates of N. gonorrhoeae among patients with putative treatment failure in a sexually transmitted disease clinic setting. Between October 2006 and August 2007, 44 isolates of N. gonorrhoeae were studied from patients identified clinically to have treatment failure with empirical ceftibuten. The ceftibuten MICs for three strains were found to have been 8 mg/liter. These strains were determined by N. gonorrhoeae multiantigen sequence typing to belong to sequence type 835 (ST835) or the closely related ST2469. The testing of an additional eight archived ST835 strains revealed similarly elevated ceftibuten MICs. The penA gene sequences of these 11 isolates all had the mosaic pattern previously described as pattern X. Of note is that the ceftriaxone susceptibility results of these strains all fell within the susceptible range. It is concluded that ceftibuten resistance may contribute to the empirical treatment failure of gonorrhea caused by strains harboring the mosaic penA gene, which confers reduced susceptibility to oral extended-spectrum cephalosporins. Screening for such resistance in the routine clinical laboratory may be undertaken by the disk diffusion test. The continued monitoring of antimicrobial resistance and molecular characteristics of N. gonorrhoeae isolates is important to ensure that control and prevention strategies remain effective.  相似文献   
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The objectives of this study were (i) to explore, following a literature review, the concepts of self-awareness, its assessment, and intervention for self-awareness deficits, as well as its clinical significance in stroke rehabilitation; and (ii) to apply the concepts of self-awareness in the context of a rehabilitation program. The search was conducted by the electronic databases Web of Science, Science Direct, MEDLINE, and PsychcInfo. A systematic literature search of publications written in English between 1980 and 2010 was conducted using the keywords, self-awareness or self-regulation. The search was limited to the following keywords: stroke, deficits, assessment, intervention, and rehabilitation. Two important conceptual models, namely, the Pyramid Model of Self-Awareness and the Dynamic Comprehensive Model of Awareness, were reviewed. Suggestions were made to the constraint-induced movement therapy for enhancement of both assessment and treatment of self-awareness deficits. In conclusion, self-awareness is essential for the success of rehabilitation. It is hoped that more studies can be conducted on the effectiveness of awareness enhancement programs incorporated in on-going therapies can be conducted, so that the evidence base can be further built up in this evolving area of practice.  相似文献   
95.
Background: A high level of low-density lipoprotein cholesterol (LDL-C) is a major risk factor for coronary artery disease (CAD). Evidence shows that lowering LDL-C improves the outcomes of patients with CAD. Atorvastatin is an established drug for the treatment of hypercholesterolemia.Objective: The purpose of this open-label, uncontrolled, prospective study was to assess the effectiveness of treatment with atorvastatin 10 mg/d for 18 weeks in achieving the target level of LDL-C (<2.6 mmol/L [<100 mg/dL]) established by the National Cholesterol Education Program (NCEP) (United States) for patients with established CAD and hypercholesterolemia.Methods: Chinese patients with CAD, hypercholesterolemia (defined as a baseline LDL-C level between 3.4 and 5.2 mmol/L [131-201 mg/dL]), and body mass index <30 kg/m2 were eligible. Atorvastatin 10 mg/d was given to each patient for 18 weeks. Lipid profiles were checked at 6, 12, and 18 weeks. To assess the extent of the achievement of NCEP LDL-C target levels, patients were categorized into 3 groups retrospectively according to baseline LDL-C level: group 1, 3.4 to 4.0 mmol/L (131-154 mg/dL); group 2, 4.01 to 4.6 mmol/L (155-178 mg/dL); and group 3, 4.61 to 5.2 mmol/L (179-201 mg/dL).Results: A total of 63 patients (50 men, 13 women; mean age, 64.3 years) were enrolled. Significant decreases in total cholesterol (31.3% at week 18), LDL-C (42.9% at week 18), and triglycerides (21.8% at week 18) from baseline levels were found at 6, 12, and 18 weeks of treatment (P < 0.001 for all). The changes in high-density lipoprotein cholesterol levels were nonsignificant. In group 1, 83.3% of patients met the target level of LDL-C; group 2, 87.5%; group 3, 37.5%; groups 1 and 2 combined, 85.2%. Atorvastatin 10 mg/d was well tolerated. Clinical adverse events were mild and transient; no severe adverse events were reported. One patient (1.6%) developed an elevated alanine aminotransferase level and withdrew. Sixty-two of 63 patients (98.4%) completed the study.Conclusions: In this group of Chinese patients with CAD and hypercholesterolemia treated with atorvastatin 10 mg/d for 18 weeks, 85.2% of patients with a baseline LDL-C level of 3.4 to 4.6 mmol/L achieved the NCEP target LDL-C level of <2.6 mmol/L, suggesting that atorvastatin 10 mg/d is efficacious in preventing secondary CAD.  相似文献   
96.
rIL-4 (B cell stimulatory factor 1) induces the expression of Fc epsilon R2/CD23 on normal human monocytes (Mo). Fc epsilon R2/CD23 induction was detectable both by flow cytometry using anti-CD23 mAbs as well as soluble IgE, and by the immunoprecipitation with CD23-specific mAb or IgE of a 45-kD band from 125I-lactoperoxidase-labeled Mo. Fc epsilon R2/CD23 was fully expressed after a 24-h incubation with rIL-4, and was still detectable after 72 h from the addition of IL-4. This effect was specific, because none of the other rILs tested (IL-1, IL-2, IL-3, IL-5, B cell stimulatory factor 2, granulocyte-macrophage colony stimulating factor, and IFN-gamma) could induce FC epsilon R2/CD23, either alone or in various combinations. No synergism was observed between IL-4 and other ILs. IFN-gamma was not able to inhibit the IL-4-induced expression of Fc epsilon R2/CD23 on Mo, neither when added to the culture together with IL-4, nor when added 36 h earlier.  相似文献   
97.
Sera from patients with primary biliary cirrhosis (PBC) react with enzymes of the 2-oxo dehydrogenase pathways, particularly PDC-E2. These enzymes are present in all nucleated cells, yet autoimmune damage is confined to biliary epithelial cells. Using a panel of eight mouse monoclonal antibodies and a human combinatorial antibody specific for PDC-E2, we examined by indirect immunofluorescence and confocal microscopy sections of liver from patients with PBC, progressive sclerosing cholangitis, and hepatocarcinoma. The monoclonal antibodies gave typical mitochondrial immunofluorescence on biliary epithelium and on hepatocytes from patients with either PBC, progressive sclerosing cholangitis, or hepatocarcinoma. However, one of eight mouse monoclonal antibodies (C355.1) and the human combinatorial antibody reacted with great intensity and specificity with the luminal region of biliary epithelial cells from patients with PBC. Simultaneous examination of these sections with an antiisotype reagent for human IgA revealed high IgA staining in the luminal region of biliary epithelial cells in patients with PBC. IgG and IgA antibodies to PDC-E2 were detected in the bile of patients with PBC but not normal controls. We believe that this data may be interpreted as indicating that a molecule cross-reactive with PDC-E2 is expressed at high levels in the luminal region of biliary epithelial cells in PBC.  相似文献   
98.
OBJECTIVE: To assess the usefulness of interleukin-6 (IL-6), tumour necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma) in the diagnosis and prediction of outcome of pleural tuberculosis. PATIENTS AND METHODS: Pleural fluid from 32 TB and 34 non-TB patients was sent for assay of IL-6, TNF-alpha and IFN-gamma. Clinical parameters at presentation and residual pleural scarring at completion of treatment were assessed for pleural TB cases. RESULTS: The pleural fluid Levels of IL-6, TNF-alpha and IFN-gamma in TB patients were significantly higher than those with non-TB effusions (P values of <0.001, 0.018 and <0.001, respectively by independent t-test). Utility of these cytokines for diagnosis of pleural TB was evaluated using receiver operating characteristic (ROC) curve analysis. The cut-off values for IL-6, TNF-alpha and IFN-gamma determined in this analysis were 4000, 4 and 60 pg/ml respectively, and their sensitivity and specificity were 90.6% and 76.5%, 90.6% and 79.4%, 100% and 100%, respectively. The pretreatment pleural fluid IL-6 levels had a positive correlation with the number of febrile days after treatment (Pearson correlation test: r=0.60, P=0.009). A negative correlation was found between the percentage reduction in pleural fluid cytokines after 2 weeks treatment and the extent of residual pleural scarring (IL-6: r=-0.62, P=0.041; TNF-alpha: r=-0.65, P=0.030; IFN-gamma: r=0.83, P=0.002). CONCLUSION: Pleural fluid IL-6, TNF-alpha and IFN-gamma assays are useful in the diagnosis of pleural TB. The initial IL-6 level correlates with the number of febrile days. The percentage change of cytokines after 2 weeks of treatment also helps to predict residual pleural scarring.  相似文献   
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