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Role of efflux pumps and mutations in genes for topoisomerases II and IV in fluoroquinolone-resistant Pseudomonas aeruginosa strains 总被引:1,自引:0,他引:1
We have investigated the occurrence of mutations in topoisomerase II (DNA gyrase) subunit B(gyrB) and topoisomerase IV subunit E(parE) and the hyperexpression of genes for four efflux pump proteins in 20 previously described, fluoroquinolone-resistant clinical strains of Pseudomonas aeruginosa. Amino acid alterations were found in GyrB in five strains and in ParE in three strains with MIC of norfloxacin > or = 8 mg/L, and it is likely that some of the alterations contribute to the quinolone resistance exhibited by these strains. Seventeen of the 20 strains overproduced mRNA for one or more pump proteins (MexB, MexD, MexF, or MexY), which caused multidrug resistance phenotype in more than half of strains. Two strains were hypermutable and one of them was highly resistant, but the other strain was only moderately resistant. 相似文献
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Jalal Poorolajal 《The journal of maternal-fetal & neonatal medicine》2016,29(22):3670-3676
Background: Several observational studies have reported a positive association between elevated body mass index (BMI) and preeclampsia, but no meta-analysis has been conducted yet. This meta-analysis was conducted to estimate the overall association between overweight or obesity and preeclampsia.Methods: Major electronic databases, including PubMed, Web of Science, and Scopus were searched until August 2015. The reference lists of included studies were screened as well. Epidemiological studies addressing the association between BMI and preeclampsia were enrolled. The heterogeneity across studies was explored by Q-test and I2 statistic. The possibility of publication bias was assessed using Begg's and Egger's tests. The results were reported using odds ratio (OR) estimate with its 95% confidence intervals (CI) using a random-effects model.Results: We identified a total of 1298 references and included 23 studies with 1 387 599 participants. Preeclampsia was associated with overweight (OR?=?1.73; 95% CI: 1.59, 1.87; 21 studies; I2?=?62.3%) and obesity (OR?=?3.15; 95% CI: 2.96, 3.35; 22 studies; I2?=?36.0%). There was no evidence of publication bias.Conclusions: There is sufficient evidence that excess body mass index is significantly associated with an increased risk of preeclampsia. Therefore, overweight and obesity can be considered as a predictor of preeclampsia. 相似文献
37.
Rapid detection and quantitation of hepatitis B virus DNA by real-time PCR using a new fluorescent (FRET) detection system. 总被引:6,自引:0,他引:6
Sani Hussein Aliyu Muktar Hassan Aliyu Hamisu M Salihu Surendra Parmar Hamid Jalal Martin David Curran 《Journal of clinical virology》2004,30(2):191-195
BACKGROUND: The diagnosis of hepatitis B virus (HBV) has until recently been based on traditional serologic methods targeting viral antigens and antibodies to viral proteins. The development of molecular methods allowing for the quantitation of HBV DNA is proving clinically valuable for monitoring therapy and detecting early treatment failures. OBJECTIVES: Here we report a new real-time (LightCycler) quantitative PCR for the detection of HBV DNA based on sequence specific hybridisation probes (designed in-house), targeting the HBV surface antigen. STUDY DESIGN: The assay was evaluated using a 10-fold dilution series of standard HBV DNA [Eurohep standard reference 1, genotype A, HBsAg subtype adw with a unitage of 10(6) WHO. i.u./ml] and 89 clinical serum samples. The performance was measured against a quantified standard HBV DNA working reagent (NIBSC code 98/780) and the sensitivity compared with our conventional thermal-block PCR. RESULTS AND CONCLUSION: Real-time PCR detected HBV DNA in 45% (40/89) and thermal-block PCR in 16% (14/75) of clinical samples. Results for 26 samples were below the detection limit of the thermal-block PCR but could be quantified by real-time (LightCycler) PCR. The LightCycler assay was at least 5 logs more sensitive than thermal-block PCR and could detect HBV in a linear range between 5 and 10(7) i.u. per reaction. The broad generic nature of the PCR primers coupled with the enhanced sensitivity and specificity of the fluorescent hybridisation probes makes this assay potentially valuable for both routine diagnostic and epidemiological work. 相似文献
38.
Seraj JM Yazdani N Ashtiani ZO Seraj SM Hasheminasab SM Memar B Mirashrafi F Borghei H Yazdani J Mostaan LV 《Pathology, research and practice》2011,207(12):758-761
In this study, we investigated the prevalence of human papilloma virus (HPV) infection and TP53 expression in patients with squamous cell carcinoma (SCC) of the tongue and, subsequently, its significance in cervical lymph node metastases and tumor differentiation. Sections of formalin-fixed, paraffin-embedded tissue blocks from 94 histologically confirmed tongue SCC cases were investigated in this study. Immunohistochemistry was used to study TP53 expression, and polymerase chain reaction (PCR) was performed for the detection of high risk HPV types (16 and 18). The frequency of HPV-16 and HPV-18 infection was 10.6% and 16%, respectively. Overexpression of TP53 was observed in 70.2% of patients. Young patients (aged below 45 years) comprised 20% of all patients. There was no significant association between TP53, HPV-16, or HPV 18 presence and higher stages of the tumor, tumor differentiation, or presence of nodal metastasis. Although an association between head and neck SCC and HPV infection is being recognized and reported, our data implicate that HPV infection or TP53 expression does not play a significant role in oral tongue SCC pathogenesis, differentiation, or metastasis, as seen in our patients. 相似文献
39.
Surveillance cultures and duration of carriage of multidrug-resistant Acinetobacter baumannii 下载免费PDF全文
Marchaim D Navon-Venezia S Schwartz D Tarabeia J Fefer I Schwaber MJ Carmeli Y 《Journal of clinical microbiology》2007,45(5):1551-1555
Isolating carriers of multidrug-resistant (MDR) Acinetobacter baumannii is the main measure to prevent its spread. Identification of carriers accompanied by contact precautions is essential. We aimed to determine the appropriate surveillance sampling sites and the duration of carriage of MDR A. baumannii. We studied prospectively two groups of patients from whom MDR A. baumannii was previously isolated: (i) those with recent clinical isolation (or=6 months). Screening for carriage was conducted from six sites: nostrils, pharynx, skin, rectum, wounds, and endotracheal aspirates. Strains recovered concurrently from different sites were genotyped using pulsed-field gel electrophoresis. Twelve of 22 with recent clinical isolation of MDR A. baumannii had >or=1 positive screening culture, resulting in a sensitivity of 55% when six body sites were sampled. Sensitivities of single sites ranged from 13.5% to 29%. Among 30 patients with remote clinical isolation, screening cultures were positive in 5 (17%), with a mean duration of 17.5 months from the last clinical culture. Remote carriers had positive screening cultures from the skin and pharynx but not from nose, rectum, wounds, or endotracheal aspirates. Eleven strains from five patients were genotyped. In all but one case, isolates from different sites in a given patient were clonal. Current methodology is suboptimal to detect MDR A. baumannii carriage. The sensitivity of surveillance cultures is low, even when six different body sites are sampled. The proportion of individuals with previous MDR A. baumannii isolation who remain carriers for prolonged periods is substantial. These data should be considered when designing measures to limit the spread of MDR A. baumannii. 相似文献
40.
Devon E. Hinton Rebecca A. Ojserkis Baland Jalal Sonith Peou Stefan G. Hofmann 《Journal of clinical psychology》2013,69(8):817-828
This article discusses how loving‐kindness can be used to treat traumatized refugees and minority groups, focusing on examples from our treatment, culturally adapted cognitive‐behavioral therapy (CA‐CBT). To show how we integrate loving‐kindness with other mindfulness interventions and why loving‐kindness should be an effective therapeutic technique, we present a typology of mindfulness states and the Nodal Network Model (NNM) of Affect and Affect Regulation. We argue that mindfulness techniques such as loving‐kindness are therapeutic for refugees and minority populations because of their potential for increasing emotional flexibility, decreasing rumination, serving as emotional regulation techniques, and forming part of a new adaptive processing mode centered on psychological flexibility. We present a case to illustrate the clinical use of loving‐kindness within the context of CA‐CBT. 相似文献