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11.
The utility of empirical combination antimicrobial therapy for Gram-negative bloodstream infection (BSI) remains unclear. This retrospective, quasi-experimental matched cohort study examined the impact of empirical combination therapy on mortality in patients with Gram-negative BSI. Hospitalized adults with Gram-negative BSI from 1 January 2010 to 31 December 2013 at Palmetto Health Hospitals in Columbia, SC, USA were identified. Patients receiving combination therapy or beta-lactam monotherapy were matched 1:1 based on age, sex and Bloodstream Infection Mortality Risk Score (BSIMRS). Multivariate Cox proportional hazards regression with propensity score adjustment was used to examine overall 28–day mortality and within predefined BSIMRS categories (<5 and ≥5). A total of 380 patients receiving combination therapy or monotherapy for Gram-negative BSI were included in the study. Median age was 66 years and 204 (54%) were female. Overall, 28-day mortality in patients who received combination therapy and monotherapy was 13% and 15%, respectively (P?=?0.51). After stratification by BSIMRS, mortality in both combination therapy and monotherapy groups was 1.1% in patients with BSIMRS <5 (P?=?0.98) and 27% and 32%, respectively, in patients with BSIMRS ≥5 (P?=?0.47). After adjusting for propensity to receive combination therapy, risk of mortality was not significantly different for combination therapy compared to monotherapy (hazard ratio [HR] 0.90, 95% confidence interval [CI] 0.51–1.60). This finding persisted for both subgroups of BSIMRS <5 (HR 0.96, 95% CI 0.04–24.28) and BSIMRS ≥5 (HR 0.83, 95% CI 0.46–1.48). There is no survival benefit from empirical combination therapy over monotherapy in patients with Gram-negative BSI, regardless of predicted prognosis at initial presentation.  相似文献   
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In this study, we applied various assays to reveal new activities of phenylcyanomethylenequinone oxime-4-(hydroxyimino) cyclohexa-2,5-dien-1-ylidene](phenyl)ethanenitrile (4-AN) for potential anti-microbial applications. These assays demonstrated (a) the antimicrobial effect on bacterial and fungal cultures, (b) the effect on the in vitro activity of the kinase CK2, (c) toxicity towards human erythrocytes, the Caco-2 cancer cell line, and embryonic development of Zebrafish. We demonstrated the activity of 4-AN against selected bacteria and Candida spp. The MIC ranging from 4?µg/ml to 125?µg/ml proved effective in inhibition of formation of hyphae and cell aggregation in Candida, which was demonstrated at the cytological level. Noteworthy, 4-AN was found to inhibit the CK2 kinase with moderate potency. Moreover, at low concentrations, it did not exert any evident toxic effects on human erythrocytes, Caco-2 cells, or Zebrafish embryos. 4-AN can be a potential candidate as a novel drug against Candida infections.  相似文献   
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Bulletin of Environmental Contamination and Toxicology - Legislation such as the Stockholm Convention and REACH aim to identify and regulate the production and use of chemicals that qualify as...  相似文献   
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Clinical evidence in oncology argues for the advantages of performing molecular analysis of blood biomarkers to provide information about systemic changes and tumor heterogeneity.Whereas the diagnostic value of cell-free circulating DNA (fcDNA) has successfully been demonstrated in several studies, DNA enclosed in extracellular vesicles (EV) has only recently been described, and its potential diagnostic value is unclear. We established a protocol for separation of EV and fc fractions and tested for presence of mutant BRAFV600E mediating resistance to Vemurafenib and cKITD816V mediating resistance to Imatinib in blood of patients with melanoma and mastocytosis. Our results show that EV contain significantly higher amounts of total DNA as compared to the fc fraction. However, about ten-fold higher copy numbers of the wild type and mutant BRAF and cKIT were detected in the fcDNA fraction supporting its diagnostic value and pointing to differences in fc and EV DNA content.  相似文献   
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Clinical and Experimental Medicine - The proto-oncogene KRAS belongs among the most frequently mutated genes in all types of cancer and is also very important oncogene related to colorectal tumors....  相似文献   
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Clinical and Experimental Medicine - Vasculopathy is a crucial feature of systemic sclerosis (SSc), and Raynaud’s phenomenon (RP) and digital ulcers (DU) have a deep impact on the quality of...  相似文献   
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PurposeThoracic aortic aneurysm (TAA) is a cardiovascular disease characterized by increased aortic diameter, treated with surgery and endovascular therapy in order to avoid aortic dissection or rupture. The mechanism of TAA formation has not been thoroughly studied and many factors have been proposed to drive its progression; however strong focus is attributed to modification of smooth muscle cells (SMCs). Latest research indicates, that microRNAs (miRNAs) may play a significant role in TAA development – these are multifunctional molecules consisting of 19–24 nucleotides involved in regulation of the gene expression level related to many biological processes, i.e. cardiovascular disease pathophysiology, immunity or inflammation.Materials and methodsPrimary SMCs were isolated from aortic scraps of TAA patients and age- and sex-matched healthy controls. Purity of isolated SMCs was determined by flow cytometry using specific markers: α-SMA, CALP, MHC and VIM. Real-time polymerase chain reaction (RT-PCR) was conducted for miRNA analysis.ResultsWe established an isolation protocol and investigated the miRNA expression level in SMCs isolated from aneurysmal and non-aneurysmal aortic samples. We identified that let-7 g (0.71-fold, p = 0.01), miR-130a (0.40-fold, p = 0.04), and miR-221 (0.49-fold, p = 0.05) significantly differed between TAA patients and healthy controls.ConclusionsFurther studies are required to improve our understanding of the pathophysiology underlying TAA, which may aid the development of novel, targeted therapies. The pivotal role of miRNAs in the cardiovascular system provides a new perspective on the pathophysiology of thoracic aortic aneurysms.  相似文献   
19.
PurposeHepatokines are proteins produced by the liver and involved in regulating glucose and lipid metabolism. However, their role as the biomarkers of intrahepatic lipid content is not clear. The aim of the study was to evaluate the serum concentration of selected hepatokines: fibroblast growth factor-21 (FGF-21), selenoprotein P (SELENOP) and sex hormone-binding globulin (SHBG) in obese children.Patients and methodsThe cross-sectional study included 86 obese children with suspected liver disease. Nonalcoholic fatty liver disease (NAFLD) was diagnosed in children with liver steatosis in ultrasound with elevated alanine aminotransferase (ALT) serum activity and excluded other liver diseases. The total intrahepatic lipid content (TILC) was assessed by magnetic resonance proton spectroscopy (1H-MRS).ResultsThe concentration of FGF-21 and SELENOP was significantly higher and SHBG significantly lower in children with NAFLD compared to controls. Only FGF-21 level was significantly higher in NAFLD children than in obese patients without NAFLD. The significant positive correlation of FGF-21 with ALT, gamma glutamyltransferase (GGT), triglycerides, homeostatic model assessment–insulin resistance (HOMA-IR), the degree of liver steatosis in ultrasound and TILC in 1H-MRS were found. The ability of serum FGF-21 to diagnose severe liver steatosis was significant.ConclusionsFGF-21 can be considered as a suitable biomarker in predicting TILC and fatty liver in obese children.  相似文献   
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