线性探针检测技术对痰标本中耐药结核分枝杆菌快速检测的应用评价

目的 评价线性探针检测技术(LPAs)直接从痰标本中检测结核分枝杆菌复合群及其对耐多药结核病的快速检测。方法 连续收取193例临床涂片抗酸染色阳性的痰标本,直接用LPAs法从痰标本中进行结核分枝杆菌复合群及其对利福平和异烟肼耐药性的检测,结果与MGIT 960系统药物敏感性试验以及利福平、异烟肼耐药相关基因rpoB、katG、inhA和ahpC的基因测序结果进行比较,评价线性探针检测技术从痰标本中检测耐药结核分枝杆菌的灵敏度、特异度和符合率。统计学分析采用kappa检验。结果 LPAs法对涂阳痰标本结核分枝杆菌复合群检测的灵敏度为100.0%,耐利福平、耐异烟肼和耐多药结核分枝杆菌复合群检测的灵敏度分别为96.0%(48/50)、92.8%(64/69)和90.0%(45/50),特异度分别为99.3%(142/143)、100.0%(124/124)和99.3%(142/143),符合率分别为98.4%(190/193)、97.4%(188/193)和96.9%(187/193)。结论 LPAs法能够直接从涂阳痰标本中检测耐多药结核分枝杆菌,对耐利福平和耐异烟肼菌株具有较高的灵敏度和特异度,与MGIT 960系统药物敏感性试验结果的一致性较好,能够明显缩短从样本接收到得到药物敏感性试验结果的报告周期,为临床准确、快速地诊断耐多药结核病提供可靠的实验室依据,有利于耐药结核病的早期诊断。     

结核感染T细胞斑点试验在手、腕部腱鞘结核诊断中的应用评价

目的 探讨结核感染T细胞斑点试验(T-cell spot of Tuberculosis,T-SPOT.TB)在手、腕部腱鞘结核诊断中的临床应用价值.方法 通过对2012年1月至2018年1月我院收集64例怀疑手、腕部腱鞘结核临床资料进行回顾性分析,根据病理诊断及临床表现判断有无结核分枝杆菌感染;全部病例均经过T-SP...     

MTT法体外药敏试验指导下的恶性胸腔积液的腔内化疗

目的探讨琼脂培养MTT法体外药敏试验指导恶性胸腔积液的胸腔内化疗的价值。方法在12 0例恶性胸腔积液病人中 ,选取 6 0例在胸膜腔内化疗前接受了琼脂培养MTT法体外药敏试验 ,其中MTT敏感组 5 2例 ,根据药敏结果指导胸膜腔内化疗 :MTT耐药组 8例和对照组 6 0例凭经验选药物行胸膜腔内化疗。结果MTT敏感组有效率为76 .9% (40 / 5 2 ) ,明显高于MTT耐药组和对照组[有效率分别为 0 % (0 / 8)及 36 .6 % (2 2 / 6 0 ) ],两者相比差异均有非常显著性 (P <0 .0 0 1)。敏感组与对照组在不同病理类型、治疗阶段和不同药物的分类比较中 ,差异也均有显著性。本研究体外药敏和体内疗效的总符合率为 80 % [(40 +8) / 6 0 ]。结论琼脂培养MTT法体外药敏试验指导恶性胸腔积液的腔内化疗是可行的     

STATISTICAL INFERENCE FOR RELATIVE POTENCY IN BIVARIATE DOSE-RESPONSE ASSAYS WITH CORRELATED RESPONSES

ABSTRACT

The analysis of dose-response assays measuring two correlated responses is considered. Attention is given to statistical inference for the potency ratio. Results from a simulation study suggest that a post hoc adjustment for the correlation in parameter estimates obtained from univariate fits provides nearly as much power to detect differences in potency as a bivariate response model fit.     

Allergenic potential of novel proteins – What can we learn from animal production?

Currently, risk assessment of the allergenic potential of novel proteins relies heavily on evaluating protein digestibility under normal conditions based on the theory that allergens are more resistant to gastrointestinal digestion than non-allergens. There is also proposed guidance for expanded in vitro digestibility assay conditions to include vulnerable sub-populations. One of the underlying rationales for the expanded guidance is that current in vitro assays do not accurately replicate the range of physiological conditions. Animal scientists have long sought to predict protein and amino acid digestibility for precision nutrition. Monogastric production animals, especially swine, have gastrointestinal systems similar to humans, and evaluating potential allergen digestibility in this context may be beneficial. Currently, there is no compelling evidence that the mechanisms sometimes postulated to be associated with allergenic sensitization, e.g. antacid modification of stomach pH, are valid among production animals. Furthermore, examples are provided where non-biologically representative assays are better at predicting protein and amino acid digestibility compared with those designed to mimic in vivo conditions. Greater emphasis should be made to align in vitro assessments with in vivo data.     

Evaluation of in vivo genotoxicity induced by N‐ethyl‐N‐nitrosourea,benzo[a]pyrene,and 4‐nitroquinoline‐1‐oxide in the Pig‐a and gpt assays

The recently developed Pig‐a mutation assay is based on flow cytometric enumeration of glycosylphosphatidylinositol (GPI) anchor‐deficient red blood cells caused by a forward mutation in the Pig‐a gene. Because the assay can be conducted in nontransgenic animals and the mutations accumulate with repeat dosing, we believe that the Pig‐a assay could be integrated into repeat‐dose toxicology studies and provides an alternative to transgenic rodent (TGR) mutation assays. The capacity and characteristics of the Pig‐a assay relative to TGR mutation assays, however, are unclear. Here, using transgenic gpt delta mice, we compared the in vivo genotoxicity of single oral doses of N‐ethyl‐N‐nitrosourea (ENU, 40 mg/kg), benzo[a]pyrene (BP, 100 and 200 mg/kg), and 4‐nitroquinoline‐1‐oxide (4NQO, 50 mg/kg) in the Pig‐a (peripheral blood) and gpt (bone marrow and liver) gene mutation assays. Pig‐a assays were conducted at 2, 4, and 7 weeks after the treatment, while gpt assays were conducted on tissues collected at the 7‐week terminal sacrifice. ENU increased both Pig‐a and gpt mutant frequencies (MFs) at all sampling times, and BP increased MFs in both assays but the Pig‐a MFs peaked at 2 weeks and then decreased. Although 4NQO increased gpt MFs in the liver, only weak, nonsignificant increases (two‐ or threefold above control) were detected in the bone marrow in both the Pig‐a and the gpt assay. These findings suggest that further studies are needed to elucidate the kinetics of the Pig‐a mutation assay in order to use it as an alternative to the TGR mutation assay. Environ. Mol. Mutagen. 54:747–754, 2013. © 2013 Wiley Periodicals, Inc.     

Frequency of antibodies to Toxocara in Cuban schoolchildren

Objective The aim of the study was to determine the frequency of antibodies to Toxocara in Cuban schoolchildren. Methods The frequency of antibodies to Toxocara canis was assessed with a commercial enzyme‐linked immunosorbent assays kit in school‐aged children from two municipalities of Cuba. Univariate analysis and a multivariable logistic regression analysis adjusted for age, sex, municipality and co‐infection with helminth and/or protozoa were conducted. Results The percentage of children with antibodies to Toxocara was 38.8% (392/1011; 95% CI = 36.8–42.8). Antibody positivity was significantly associated with gender and co‐infections with intestinal parasites, but not with age or municipality. Conclusion Cuban children are highly exposed to the Toxocara parasite, corresponding well with reported environmental contamination with Toxocara parasite eggs and T. canis prevalences in dogs in Cuba. Relevant policy makers and the Cuban population need to be better informed about this preventable infection.     

Effect of a one‐step self‐etch adhesive on endogenous dentin matrix metalloproteinases

Degradation of the hybrid layer created in dentin by dentin adhesives is caused by enzyme activities present within the dentin matrix that destroy unprotected collagen fibrils. The aim of the present study was to evaluate the effect of a one‐step self‐etch adhesive system on dentinal matrix metalloproteinases 2 and 4 (MMP‐2 and MMP‐9, respectively) using in situ zymography and an enzymatic activity assay. The null hypothesis tested was that there are no differences in the activities of dentinal MMPs before and after treatment with a one‐step adhesive system. The MMP‐2 and MMP‐9 activities in dentin treated with the one‐step adhesive, Adper Easy Bond, were quantified using an enzymatic activity assay system. The MMP activities within the hybrid layer created by the one‐step adhesive tested were also evaluated using in situ zymography. The enzymatic assay revealed an increase in MMP‐2 and MMP‐9 activities after treatment with adhesive. In situ zymography indicated that gelatinolytic activity is present within the hybrid layer created with the one‐step self‐etch adhesive. The host‐derived gelatinases were localized within the hybrid layer and remained active after the bonding procedure. It is concluded that the one‐step self‐etch adhesive investigated activates endogenous MMP‐2 and MMP‐9 with the dentin matrix, which may cause collagen degradation over time.