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Background

With the worldwide spread of antibiotic resistance, delivering antibiotic susceptibility test (AST) results in a timely manner represents a major challenge. In cases of sepsis, rapid AST may facilitate early optimization of empiric antibiotic therapy. Disc diffusion is a well-standardized AST method, however 16 to 24?h are required to achieve an overall AST profile according to antimicrobial societies.

Methods

In this prospective pilot study, we evaluated the performance of Mueller-Hinton-Rapid-SIR (MHR-SIR) agar after 6–8?h of incubation in comparison with standard MH agar after 16?h of incubation directly on positive blood cultures caused by Enterobacteriaceae and Staphylococcus aureus from routine clinical microbiology.A total of 133 positive blood samples including 110 Enterobacteriaceae (83%) and 23 Staphylococcus aureus (17%) were tested in parallel by two direct AST methods, each using EUCAST breakpoints. For each combination bacterium and antibiotic, we compared the categorical agreement and the correlation between the diameters obtained by MHR-SIR and by standard MH.

Results

Our results showed 97.7% categorical agreement for Enterobacteriaceae, with 1.4% minor errors, 0.4% major errors and 0.5% very major errors. For S. aureus, we observed 97.8% categorical agreement, 1.9% minor errors, 0.3% major errors and no very major errors.

Conclusion

Our results showed excellent categorical agreement and correlations between diameters for MHR-SIR and standard MH methods. MHRSIR can predict the result of overall AST profile within 6–8?h with reliable results. AST is obtained on the same day the blood culture becomes positive, with a very moderate cost.  相似文献   
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Breast cancer incidence continues to increase in the US and Europe, a reflection of the growing influence of environment factors that interact with personal genetics. The US Environmental Protection Agency estimates that there are approximately 10,000 endocrine disrupting chemicals among the common daily exposures that could affect the risk of disease. The daunting tasks of identifying, characterizing, and elucidating the mechanisms of endocrine disrupting chemicals in breast cancer need to be addressed to produce a comprehensive model that will facilitate preventive strategies and public policy. An expert panel met to describe and bring attention to needs linking common environmental exposures, critical windows of exposure, and optimal times of assessment in investigating breast cancer risk. The group included investigators with extensive experience in the use of rodent models and in leading population studies and produced a set of recommendations for effective approaches to gaining insights into the environmental origins of breast cancer across the lifespan.  相似文献   
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In our previous meta‐analysis of genome‐wide association study, we identified the single nucleotide polymorphism (SNP) rs4948496 (= 5.1 × 10?11, odds ratio [OR] = 0.85) within the ARID5B gene associated with systemic lupus erythematosus (SLE) in a Chinese population. To investigate its association with disease subphenotypes, we further analyzed the genotype data of rs4948496 in 4348 cases and 6679 controls from our previous meta‐analysis and an independent replication cohort in this study. The SNP rs4948496 was significantly associated with SLE (= 1.61 × 10?5, OR = 0.88, 95% confidence interval [CI] = 0.83–0.93) in our group. In case‐only study, the genotype of rs4948496 was associated with antinuclear antibodies (= 0.03, OR = 0.81, 95% CI = 0.68–0.98) and anti‐RNP (= 0.03, OR = 0.86, 95% CI = 0.76–0.99). This study showed that rs4948496 in ARID5B is associated with several subphenotypes of SLE and this gene may cause the complicacy of clinical features.  相似文献   
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摘要:目的以分子测序为参考 ,评估形态学、基质辅助激光解吸电离飞行时间质谱对毛霉目真菌的鉴定能力,分析毛霉目真菌对两性霉素B、泊沙康唑的体外药敏特点。方法收集 2018年1月-2022年2月广东省人民医院25例毛霉病住院患者标 本,进行镜检并对培养的茵落行形态学鉴定、质谱鉴定、分子测序和体外药敏试验。结果KOH 湿片法阳性率(76%)高于革兰染色法(32%),差异有统计学意义(P<0.05);形态学鉴定可将68%的菌株鉴定到属水平,3株鉴定错误,2株无法鉴定;将所 有菌株进行质谱鉴定,单用IVD和RUO数据库鉴定率分别为56%和44%,两库联合可将鉴定率提高为64%。毛霉目真菌对两性霉素B的抑制50%菌株生长的最小抑菌浓度(MIC3o)为1μg/mL,根霉属相比其他属对两性霉素B表现出较高的MIC 值,其中2株MIC>32 μg/mL,另2株MIC为8 μg/mL;根霉属对泊沙康唑的MICso为0.5 μg/mL,横梗霉属MICgo为4 μg/ mL,小克银汉霉属MICg0为2 μg/mL,有部分菌株表现出较低MIC值,同样亦有部分菌株对泊沙康唑表现出较高的MIC 值。结论 将传统镜检、培养与质谱技术和分子技术相结合,尽量将毛霉目真菌准确鉴定到种,并积极开展毛霉体外药敏试验,可为临床治疗提供参考依据。  相似文献   
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Long non-coding RNAs (lncRNAs) have been identified as crucial regulators in the tumorigenesis and progression of hepatocellular carcinoma (HCC). Recently, long intergenic non-protein coding RNA 205 (LINC00205) has been identified as a prognostic biomarker in HCC. However, the biological role of LINC0205 and its potential molecular mechanism are poorly investigated. Here, we found that the expression of LINC00205 was dramatically up-regulated in HCC tissues compared to adjacent nontumor tissues. Furthermore, the level of LINC00205 in both Hep3B and Huh7 cells was prominently higher than that in normal hepatic cell line LO2. Notably, the high expression of LINC00205 was strongly correlated with tumor size ≥5 cm, venous infiltration and advanced tumor stages. Functionally, LINC00205 knockdown obviously repressed the proliferation, migration and invasion of Hep3B and Huh7 cells in vitro. An inverse correlation between LINC00205 and miR-122-5p was detected in HCC tissues. Interestingly, LINC00205 knockdown increased the level of miR-122-5p in both Hep3B and Huh7 cells. Mechanistically, luciferase reporter assay demonstrated LINC00205 acted as a competing endogenous RNA (ceRNA) by directly interacting with miR-122-5p. More importantly, miR-122-5p overexpression significantly restrained the proliferation, migration and invasion of HCC cells. Collectively, our study provides solid evidence to support the oncogenic role of LINC00205 in HCC, which may be benefit for the improvement of HCC therapy.  相似文献   
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