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91.
《Vaccine》2015,33(21):2470-2476
Background/objectivesAnthrax vaccine adsorbed (AVA, BioThrax®) is recommended for post-exposure prophylaxis administration for the US population in response to large-scale Bacillus anthracis spore exposure. However, no information exists on AVA use in children and ethical barriers exist to performing pre-event pediatric AVA studies. A Presidential Ethics Commission proposed a potential pathway for such studies utilizing an age de-escalation process comparing safety and immunogenicity data from 18 to 20 year-olds to older adults and if acceptable proceeding to evaluations in younger adolescents. We conducted exploratory summary re-analyses of existing databases from 18 to 20 year-olds (n = 74) compared to adults aged 21 to 29 years (n = 243) who participated in four previous US government funded AVA studies.MethodsData extracted from studies included elicited local injection-site and systemic adverse events (AEs) following AVA doses given subcutaneously at 0, 2, and 4 weeks. Additionally, proportions of subjects with ≥4-fold antibody rises from baseline to post-second and post-third AVA doses (seroresponse) were obtained.ResultsRates of any elicited local AEs were not significantly different between younger and older age groups for local events (79.2% vs. 83.8%, P = 0.120) or systemic events (45.4% vs. 50.5%, P = 0.188). Robust and similar proportions of seroresponses to vaccination were observed in both age groups.ConclusionsAVA was safe and immunogenic in 18 to 20 year-olds compared to 21 to 29 year-olds. These results provide initial information to anthrax and pediatric specialists if AVA studies in adolescents are required. 相似文献
92.
Microbial detoxification of deoxynivalenol (DON) represents a new approach to treating DON-contaminated grains. A bacterium Devosia mutans 17-2-E-8 was capable of completely transforming DON into a major product 3-epi-DON and a minor product 3-keto-DON. Evaluation of toxicities of these DON-transformation products is an important part of hazard characterization prior to commercialization of the biotransformation application. Cytotoxicities of the products were demonstrated by two assays: a MTT bioassay assessing cell viability and a BrdU assay assessing DNA synthesis. Compared with DON, the IC50 values of 3-epi-DON and 3-keto-DON were respectively 357 and 3.03 times higher in the MTT bioassay, and were respectively 1181 and 4.54 times higher in the BrdU bioassay. Toxicological effects of 14-day oral exposure of the B6C3F1 mouse to DON and 3-epi-DON were also investigated. Overall, there were no differences between the control (free of toxin) and the 25 mg/kg bw/day or 100 mg/kg bw/day 3-epi-DON treatments in body and organ weights, hematology and organ histopathology. However, in mice exposed to DON (2 mg/kg bw/day), white blood cell numbers and serum immunoglobulin levels were altered relative to controls, and lesions were observed in adrenals, thymus, stomach, spleen and colon. Taken together, in vitro and in vivo studies indicate that 3-epi-DON is substantially less toxic than DON. 相似文献
93.
Edmondo Falleti Carlo Fabris Mario Pirisi Giorgio Soardo Daniela Vitulli Pierluigi Toniutto Nadia Bortolotti Fabio Gonano Ettore Bartoli 《Journal of cancer research and clinical oncology》1996,122(6):366-369
Molecules governing cellular interactions have been suggested to be involved in the spurious elevation of 1-fetoprotein (AFP) in non-neoplastic liver disease. To explore this controversial issue, we measured AFP, circulating intercellular adhesion molecule 1 (cICAM-1), and common liver function tests in 111 patients (71 male, 40 female). Eighty-four patients had non-neoplastic chronic liver disease and 27 had hepatocellular carcinoma. The concentration of cICAM-1 was determined immunoenzymatically. In patients with non-neoplastic chronic liver disease, univariate analysis demonstrated a significant correlation between AFP and cholinesterase (R=–0.397,P<0.001), aspartate aminotransferase (R=0.421,P<0.001), bilirubin (R=0.231,P<0.05) and cICAM-1 (R=0.430,P<0.001). Multivariate analysis among these variables and AFP indicated cICAM-1 to be the strongest independent predictor of AFP. We conclude that cICAM-1 compares favourably with liver function tests in predicting non-specific AFP variations in non-neoplastic chronic liver disease, suggesting a link between targeting of the inflammatory damage to the hepatocyte and development of neoplasia.Abbreviations
AFP
1-fetoprotein
-
cICAM-1
circulating intercellular adhesion molecule 1 相似文献
94.
A modified osmotic fragility test, based on measurement of hemolysis in four hypotonic NaCl solutions and logarithmic linearization of osmotic fragility curve is, like the "Pink test," a specific and sensitive test for the laboratory diagnosis of hereditary spherocytosis. 相似文献
95.
Nika Drinkovi MD 《The American journal of cardiology》1981,47(6):1260-1265
To assess the value of subcostal echocardiography in determining the position of a right ventricular pacing catheter, M mode and two dimensional echocardiography was performed from four different locations in 30 patients. Subcostal M mode echocardiography had a higher detection rate of the pacing catheter than did the precordial M mode examination. However, with M mode echocardiography it was not possible to determine the position of the pacing catheter from any of the locations. The subcostal two dimensional echocardiography demonstrated the full length of the pacing catheter in the right heart chambers and its anatomic position in all patients and proved superior to the precordial approach. This technique allowed the detection of complications related to pacing catheters. A pacing catheter ejected from the ventricular cavity was found in the inferior vena cava. Perforation of the ventricular septum with a bipolar electrode for temporary pacing was also diagnosed.
Subcostal two dimensional echocardiography was used in 20 patients as an additional technique for controlling the advancement of electrode catheters in right heart intracardiac electrophysiologic studies. The electrode catheters were successfully positioned at all routine sites in all patients except one. Thus, subcostal two dimensional echocardiography has advantages over fluoroscopy in the determination of pacing catheter position and in controlling the advancement of electrode catheters in intracardiac electrophysiologic studies. 相似文献
96.
目的 建立泻白散和方中3味主药甘草、地骨皮、桑白皮的体外抗氧化活性测定方法,并对31批药材和10批泻白散煎液的抗氧化活性进行测定。方法 采用紫外可见分光光度法检测一定浓度的药材提取液引起DPPH溶液吸光度(A)值降低,考察波长为517 nm,分别探索3味药材抗氧化活性成分的提取条件;并进行不同溶剂的吸收考察、专属性考察、DPPH线性考察、药材提取液线性考察、精密度试验、重复性试验、耐用性考察等方法学验证;以清除DPPH自由基的半抑制浓度(IC50)作为评价指标,对泻白散和方中3味药材的体外抗氧化活性进行考察。结果 地骨皮、甘草、桑白皮和泻白散提取液的IC50均值为0.31、1.24、1.49和0.91 g/L,泻白散提取工艺对方中药物抗氧化活性的保留均值为56%。结论 建立的抗氧化活性测定方法可用于泻白散及方中主药的抗氧化活性测定,为多维度评价中药和中药材质量提供新思路。 相似文献
97.
目的分析9例遗传性凝血因子Ⅴ(FⅤ)缺乏症患者的临床表现及分子致病机制。方法对1999年4月至2019年9月就诊于中国医学科学院血液病医院的9例遗传性FⅤ缺乏症患者进行回顾性分析:应用活化部分凝血活酶时间(APTT)、凝血酶原时间(PT)及FⅤ促凝活性(FⅤ∶C)测定进行表型诊断;使用高通量靶向测序筛查F5基因变异,Sanger测序验证并分析双亲携带情况;Swiss-model进行三维结构分析,ClustalX-2.1软件进行同源保守性分析。结果9例患者的FⅤ∶C为0.1~10.6 U/dl,其中8例患者有出血病史,以皮肤/黏膜出血最为多见(3例),其余1例未发生出血事件。所有患者中纯合子5例,复合杂合子4例,共检测到12个致病或疑似致病F5基因突变,其中c.6100C>A/p.Pro2034Thr、c.6575T>C/p.Phe2192Ser、c.1600_1601delinsTG/p.Gln534*、c.4713C>A/p.Tyr1571*和c.952+5G>C为首次报道。结论该研究新发现的基因突变丰富了与遗传性FⅤ缺乏症相关F5基因突变谱,高通量测序方法可以有效检测F5基因突变。 相似文献
98.
99.
Samantha J. Broyd Lisa-marie Greenwood Rodney J. Croft Anna Dalecki Juanita Todd Patricia T. Michie Stuart J. Johnstone Nadia Solowij 《International journal of psychophysiology》2013
Chronic cannabis use has been associated with neurocognitive deficits, alterations in brain structure and function, and with psychosis. This study investigated the effects of chronic cannabis use on P50 sensory-gating in regular users, and explored the association between sensory gating, cannabis use history and the development of psychotic-like symptoms. Twenty controls and 21 regular cannabis users completed a P50 paired-click (S1 and S2) paradigm with an inter-pair interval of 9 s. The groups were compared on P50 amplitude to S1 and S2, P50 ratio (S2/S1) and P50 difference score (S1–S2). While cannabis users overall did not differ from controls on P50 measures, prolonged duration of regular use was associated with greater impairment in sensory gating as indexed by both P50 ratio and difference scores (including after controlling for tobacco use). Long-term cannabis users were found to have worse sensory gating ratios and difference scores compared to short-term users and controls. P50 metrics did not correlate significantly with any measure of psychotic-like symptoms in cannabis users. These results suggest that prolonged exposure to cannabis results in impaired P50 sensory-gating in long-term cannabis users. While it is possible that these deficits may have pre-dated cannabis use and reflect a vulnerability to cannabis use, their association with increasing years of cannabis use suggests that this is not the case. Impaired P50 sensory-gating ratios have also been reported in patients with schizophrenia and may indicate a similar underlying pathology. 相似文献
100.
Klemens Horst Silke Ganzera Wolfgang Kaisers Johanna Munding Berenike Flott-Rahmel Andrea Tannapfel Hubert Zirngibl 《Pathology, research and practice》2013
The MRE11/RAD50/NIBRIN complex, a protein complex that repairs DNA double-strand breaks, could serve as an early marker for new lesions in pancreatic cancer. We determined the expression of MRE11, RAD50 and NIBRIN, and their possible prognostic value regarding survival. 相似文献