噬菌体变色法检测结核分枝杆菌

目的建立一种结核分枝杆菌快速检测方法。方法痰标本常规处理,离心集菌,取100μl于试管中,另一支加入标准株H37Rv结核分枝杆菌作阳性对照。两支试管分别加入噬菌体D29,37℃培养,用硫酸亚铁铵杀死结核分枝杆菌菌体外的噬菌体,柠檬酸三钠和氯化钙混和液中和硫酸亚铁铵。加入耻垢分枝杆菌和硝酸钾,37℃培养过夜,加入显色剂显色。同时用罗氏培养方法对照检测。结果临床标本的噬菌体变色法和罗氏培养法表明两方法结果具有一致性(P0.05)。结论噬菌体变色法可作为结核分枝杆菌的快速检测方法之一。     

A genome-wide search for quantitative trait loci contributing to variation in seasonal pollen reactivity

BACKGROUND: Asthma and atopy represent complex traits for which genetic predisposition has been demonstrated. Pollen sensitivity, whether seasonal or chronic, appears to be a major contributor to the asthmatic phenotype. OBJECTIVE: Regions of the genome contributing to skin test reactivity to 5 seasonal allergens are to be identified in a genome-wide scan. These regions may be distinct from those contributing to risk for asthma and/or atopy. METHODS: In the Collaborative Study on the Genetics of Asthma, 4 sites collected 287 families with 2 or more members with asthma. Reactivity to individual pollens were determined on all family members. A genome scan was performed at 9-centiMorgan intervals, and skin test reactivity to 5 seasonal allergens was the focus of nonparametric genetic linkage analysis. RESULTS: Chromosomal regions that exhibited suggestive linkage (logarithm of the odds >1.18; P < .01) to seasonal pollen reactivity were identified on chromosomes 13q34, 20p12, and 21q21. Evidence of ethnic differences in linkage to seasonal allergens was demonstrated, with support for linkage in African American subjects on chromosomes 8, 10, and 12, in European American subjects on chromosomes 14, 19, 20, and 22, and in Hispanics on chromosome 21. In all families, evidence for linkage of skin test reactivity for Betula, Lolium, and Artemisia was strongest in a region on chromosome 21 that contained the candidate gene, A Disintegrin And Metalloprotease domain 33 (ADAM33). CONCLUSION: These results suggest both substantial genetic overlap and extensive heterogeneity in the genetic basis for the allergic response to seasonal allergens.     

IL13 promoter polymorphism 1112C/T modulates the adverse effect of tobacco smoking on lung function

RATIONALE: Although the duration and amount of cigarette smoking correlate with reduction in pulmonary function, there is still variation among individual responses. IL-13 is involved in pulmonary inflammation, remodeling, and susceptibility to chronic obstructive pulmonary disease (COPD). OBJECTIVES: We investigated whether the relationships between smoking and the lung function measures FEV(1) and FEV(1)/FVC ratio are modulated by IL13 polymorphisms. METHODS: Smokers (>or=20 pack-years), aged at least 40 years old (n = 1,073), were genotyped for three single nucleotide polymorphisms (SNPs; -1112C/T [rs1800925], +2044G/A [rs20541, R130Q], and +2525G/A [rs1295685]) in the IL13 gene. Linear, quantile, and logistic regression methods were used to assess the effect of cigarette smoking (pack-years), IL13 polymorphisms, and their interaction on %predicted FEV(1) and FEV(1)/FVC ratio. Age, sex, and current smoking status were included as confounders. MEASUREMENTS AND MAIN RESULTS: The number of pack-years smoked was associated with a lower value for both %predicted FEV(1) and FEV(1)/FVC (P < 0.001).The three SNPs were not associated with lung function measures; however, there was a significant combined effect between smoking and the promoter polymorphism -1112C/T on %predicted FEV(1) (P for interaction < 0.03 for mean %predicted FEV(1) and < 0.0001 for 90th percentile %predicted FEV(1)). Every 20-pack-year increment in smoking was associated with a 2.4% reduction in mean %predicted FEV(1) in the common homozygous (CC) or heterozygous (CT) promoter genotypes, and an 8.2% reduction in mean %predicted FEV(1) in minor allele homozygotes (TT, recessive model). CONCLUSIONS: An IL13 polymorphism in the promoter region may modulate the adverse effects of cigarette smoking on pulmonary function in long-term cigarette smokers.     

TNFα receptor genotype influences smoking-induced muscle-fibre-type shift and atrophy in mice

Systemic manifestations of chronic obstructive pulmonary disease (COPD) include muscle wasting, and tumour necrosis factor alpha (TNFalpha) could represent a major inducer of these processes. We studied skeletal muscle histology in a murine model of cigarette smoke (CS)-induced COPD, comparing mice with different TNFalpha receptor genotypes. Muscles from hind limbs of wild type (WT), TNFalpha receptor 1 knockout (TNF alpha R1KO) and TNF alpha R2KO mice were prepared and weighed. The lower body weight, which was observed in CS-exposed WT and TNF alpha R1KO mice, was paralleled by reduced weights of gastrocnemius and biceps femoris muscle. The gastrocnemius muscle was evaluated for muscle fibre apoptosis and atrophy, and fibre-type distribution. CS-induced apoptosis was observed in all genotypes, while a significant reduction of cross-sectional areas of myofibres was present only in TNF alpha R2KO mice. A CS-induced fibre-type shift from the IIa to the IIb phenotype was observed in WT mice, an increase of muscle-fibre-type IIx was noticed in CS-exposed TNF alpha R2KO mice. Our data suggest that the skeletal muscle manifestations associated with this murine COPD model are under complex regulation by both TNFalpha receptors, but that TNF alpha R2 may be the most important determinant for the outcome of CS-induced myofibre apoptosis.     

Lutein/zeaxanthin isomers regulate neurotrophic factors and synaptic plasticity in trained rats

Background/aim This study was conducted to elucidate the effects of lutein/zeaxanthin isomers (L/Zi) on lipid metabolism, oxidative stress, NF-κB/Nrf2 pathways, and synaptic plasticity proteins in trained rats.Materials and methods Wistar rats were distributed into four groups: 1) control, 2) L/Zi: rats received L/Zi at the dose of 100 mg/kg by oral gavage, 3) exercise, 4) exercise+L/Zi: rats exercised and received L/Zi (100 mg/kg) by oral gavage. The duration of the study was eight weeks. Results Exercise combined with L/Zi reduced lipid peroxidation and improved antioxidant enzyme activities of muscle and cerebral cortex in rats (p < 0.001). In the Exercise + L/Zi group, muscle and cerebral cortex Nrf2 and HO-1 levels increased, while NF-κB levels decreased (p <0.001). Also, L/Zi improved BDNF, synapsin I, SYP, and GAP-43 levels of the cerebral cortex of trained rats (p < 0.001). The highest levels of BDNF, synapsin SYP, and GAP-43 in the cerebral cortex were determined in the Exercise+L/Zi group.Conclusion These results suggested that exercise combined with L/Zi supplementation might be effective to reduce neurodegeneration via improving neurotrophic factors and synaptic proteins, and oxidative capacity in the cerebral cortex.     

Evaluation of systemic involvement of Coronavirus disease 2019 through spleen; size and texture analysis

Background/aimTo investigate the changes in the spleen size, parenchymal heterogeneity, and computed tomography (CT) texture analysis features of patients diagnosed with Coronavirus disease 2019 (COVID-19)Materials and methodsThe size and parenchymal structure of the spleen in 91 patients who underwent thoracic CT examination due to COVID-19 were evaluated. For the evaluation of parenchymal heterogeneity, CT texture analysis was performed using dedicated software (Olea Medical, France). The texture analysis of each case consisted of 15 first-order intensity-based features, 17 gray level co-occurrence matrix-based features, and 9 gray level run length matrix-based features.ResultsA total of 91 patients (45 males, 46 females) with a mean age of 54.31 ± 16.33 years (range: 18–81) were included in the study. A statistically significant decrease in spleen size was seen in the follow-up CT examinations (p < 0.001) whereas no statistically significant difference was found between the Hounsfield unit (HU) values. The radiomics consisted of first-order intensity-based features such as 90th percentile, maximum, interquartile range, range, mean absolute deviation, standard deviation, and variance, all of which showed statistically significant differences (p - values: < 0.001, < 0.001, 0.001, 0.003, 0.001, 0.001, and 0.004, respectively). “Correlation” as a gray level co-occurrence matrix-based feature and “gray level nonuniformity” as a gray level run length matrix-based feature showed statistically differences (p-values: 0.033 and < 0.001, respectively).ConclusionsAlthough COVID-19 manifests with lung involvement in the early stage, it can also cause systemic involvement, and the spleen may be one of its target organs. A decrease in the spleen size and parenchymal microstructure changes can be observed in the short follow-up time. It is hoped that the changes in the parenchymal microstructure will be demonstrated by a noninvasive method: texture analysis.