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It has been demonstrated that obesity is an independent risk factor for worse outcomes in patients with COVID-19. Our objectives were to investigate which classes of obesity are associated with higher in-hospital mortality and to assess the association between obesity and systemic inflammation. This was a retrospective study which included consecutive hospitalized patients with COVID-19 in a tertiary center. Three thousand five hundred thirty patients were included in this analysis (female sex: 1579, median age: 65 years). The median body mass index (BMI) was 28.8 kg/m2. In the overall cohort, a J-shaped association between BMI and in-hospital mortality was depicted. In the subgroup of men, BMI 35–39.9 kg/m2 and BMI ≥40 kg/m2 were found to have significant association with higher in-hospital mortality, while only BMI ≥40 kg/m2 was found significant in the subgroup of women. No significant association between BMI and IL-6 was noted. Obesity classes II and III in men and obesity class III in women were independently associated with higher in-hospital mortality in patients with COVID-19. The male population with severe obesity was the one that mainly drove this association. No significant association between BMI and IL-6 was noted.

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Magnetic particle-based immunoassays are widely used in microbiology-related assays for both microbial capture, separation, analysis, and detection. Besides facilitating sample operation, the implementation of micro-to-nanometer scale magnetic beads as a solid support potentially shortens the incubation time (for magnetic immuno capture) from several hours to less than an hour. Analytical technologies based on magnetic beads offer a rapid, effective and inexpensive way to separate and concentrate the target analytes prior to detection. Magneto-immuno separation uses magnetic particles coated with specific antibodies to capture target microorganisms, bear the corresponding antigens, and subsequently separate them from the sample matrix in a magnetic field. The method has been proven effective in separating various types of pathogenic bacteria from environmental water samples and in eliminating background interferences. Magnetic particles are often used to capture target cells (pathogenic bacteria) from samples. In most commercially available assays, the actual identification and quantitation of the captured cells is then performed by classical microbiological assays. This review highlights the most sensitive analytic methods (i.e., long-range surface plasmon resonance and electrochemical impedance spectroscopy) to detect magnetically tagged bacteria in conjunction with magnetic actuation.  相似文献   
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BackgroundBlood eosinophil (B‐Eos) count is an emerging biomarker in the management of respiratory disease but determinants of B‐Eos count besides respiratory disease are poorly described. Therefore, we aimed to evaluate the influence of non‐respiratory diseases on B‐Eos count, in comparison to the effect on two other biomarkers: fraction of exhaled nitric oxide (FeNO) and C‐reactive protein (CRP), and to identify individual characteristics associated with B‐Eos count in healthy controls.MethodsChildren/adolescents (<18 years) and adults with complete B‐Eos data from the US National Health and Nutritional Examination Surveys 2005–2016 were included, and they were divided into having respiratory diseases (n = 3333 and n = 7,894, respectively) or not having respiratory disease (n = 8944 and n = 15,010, respectively). After excluding any respiratory disease, the association between B‐Eos count, FeNO or CRP, and non‐respiratory diseases was analyzed in multivariate models and multicollinearity was tested. After excluding also non‐respiratory diseases independently associated with B‐Eos count (giving healthy controls; 8944 children/adolescents and 5667 adults), the independent association between individual characteristics and B‐Eos count was analyzed.ResultsIn adults, metabolic syndrome, heart disease or stroke was independently associated with higher B‐Eos count (12%, 13%, and 15%, respectively), whereas no associations were found with FeNO or CRP. In healthy controls, male sex or being obese was associated with higher B‐Eos counts, both in children/adolescents (15% and 3% higher, respectively) and adults (14% and 19% higher, respectively) (p < 0.01 all). A significant influence of race/ethnicity was also noted, and current smokers had 17% higher B‐Eos count than never smokers (p < 0.001).ConclusionsNon‐respiratory diseases influence B‐Eos count but not FeNO or CRP. Male sex, obesity, certain races/ethnicities, and current smoking are individual characteristics or exposures that are associated with higher B‐Eos counts. All these factors should be considered when using B‐Eos count in the management of respiratory disease.  相似文献   
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Phase-derived parameters and time autocorrelation functions were used to analyze the behavior of murine B16 cells exposed to different amplitudes of electroporation pulses. Cells were observed using an off-axis digital holographic microscope equipped with a fast camera. Series of quantitative phase images of cells were reconstructed and further processed using MATLAB codes. Projected area, dry mass density, and entropy proved to be predictors for permeabilized cells that swell or collapse. Autocorrelation functions of phase fluctuations in different regions of the cell showed a good correlation with the local effectiveness of permeabilization.  相似文献   
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Here, we describe the isolation and characterization of the rhesus macaque homolog for human DC-SIGN, a dendritic cell-specific C-type lectin. mac-DC-SIGN is 92% identical to hu-DC-SIGN. mac-DC-SIGN preserves the virus transmission function of hu-DC-SIGN, capturing and efficiently transducing simian and human immunodeficiency virus to target CD4(+) T cells. Surprisingly, however, mac-DC-SIGN plays no discernable role in the ability of rhesus macaque dendritic cells to capture and transmit primate lentiviruses. Expression and neutralization analyses suggest that this process is DC-SIGN independent in macaque, although the participation of other lectin molecules cannot be ruled out. The ability of primate lentiviruses to effectively use human and rhesus dendritic cells in virus transmission without the cells becoming directly infected suggests that these viruses have taken advantage of a conserved dendritic cell mechanism in which DC-SIGN family molecules are significant contributors but not the only participants.  相似文献   
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The Treating to New Targets (TNT) study demonstrated that intensive atorvastatin therapy to achieve low-density lipoprotein cholesterol concentrations well below recommended target levels provides an incremental clinical benefit in patients with stable coronary artery disease. This post hoc analysis of the TNT study was conducted to investigate whether this benefit extends to patients with previous percutaneous coronary intervention (PCI). A total of 10,001 patients with clinically evident coronary artery disease, including 5,407 patients with previous PCI, were randomized to atorvastatin 10 or 80 mg/day and followed for a median of 4.9 years. The primary end point was the occurrence of a first major cardiovascular event. Revascularization, a component of a secondary end point, was also examined. In patients with previous PCI, mean low-density lipoprotein cholesterol levels at study end were 79.5 mg/dl in the 80-mg arm and 100.8 mg/dl in the 10-mg arm. First major cardiovascular events occurred in 230 patients (8.6%) receiving high-dose atorvastatin and 289 patients (10.6%) receiving low-dose atorvastatin (hazard ratio 0.79, 95% confidence interval 0.67 to 0.94, p = 0.008). Repeat revascularization during follow-up (PCI or coronary artery bypass grafting) was performed in 466 patients (17.3%) in the 80-mg arm and 624 patients (22.9%) in the 10-mg arm (hazard ratio 0.73, 95% confidence interval 0.65 to 0.82, p <0.0001). In conclusion, intensive lipid lowering to a mean low-density lipoprotein cholesterol level of 79.5 mg/dl (2.1 mmol/L) with atorvastatin 80 mg/day in patients with previous PCI reduces major cardiovascular events by 21% and repeat revascularizations by 27% compared with a less intensive lipid-lowering regimen.  相似文献   
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