Effect of various stabilizing agents on Imperata cylindrica grass pollen allergen extract

BACKGROUND: Allergen extracts are unstable, heat labile or susceptible to proteases. Stability of allergen extracts is important for proper diagnosis and therapy of allergic disorders. OBJECTIVE: The present study was undertaken to determine the preservation and stabilization conditions of Imperata cylindrica (Ic) grass pollen extract. METHODS: The Ic extract was kept with 0.1 mepsilon-aminocaproic acid (EACA), 0.75 m sucrose, 5% glycerol, 0.03% human serum albumin (HSA) or 0.4% phenol for different time periods. The extracts were stored for 3, 6 and 12 months each at 4 degrees C, 4 degrees C with daily exposure to room temperature (RT) for 1 h, and RT. The quality of extracts was analysed by SDS-PAGE, Western blot, ELISA, ELISA inhibition and skin test. RESULTS: Extracts kept with EACA and sucrose retained most of the protein bands followed by glycerol as determined by SDS-PAGE and Western blot during all storage periods and conditions in comparison with standard extracts. The extracts kept with HSA, phenol and without preservative (WP) showed protein degradation below 33 kDa after 3 months storage at all conditions. However, a 67-kDa allergen was stable in these extracts. EACA extract required 75 to 120 ng of protein for 50% inhibition in IgE binding under different conditions, whereas standard extract required 70 ng for the same. ELISA also demonstrated high allergenic reactivity of EACA extract. ID test on allergy patients with EACA extract demonstrated same allergenic potency as that of standard extract. CONCLUSION: EACA is the best preservative/stabilizing agent of Ic pollen extract, followed by sucrose and glycerol. Ic extract kept with phenol, HSA and without preservative showed degradation within 3 months. EACA preserved extract is equally potent as that of standard extract up to 1 year's storage.     

Should harm minimization as an approach to adolescent substance use be embraced by junior and senior high schools?: Empirical evidence from An integrated school- and community-based demonstration intervention addressing drug use among adolescents

The objective of this demonstration project was to determine if school-based harm minimization drug education was potentially acceptable and effective for junior and senior high school students in Nova Scotia. We conducted a four-year quasi-experimental intervention using mixed quantitative and qualitative methodologies. The intervention was a co-operative participatory research project with various activities determined by the participants. The project involved a partnership of four schools, two school boards, two regional addiction services, the provincial department of health, and a university. The outcomes evaluation was based on a sample of 1117 and 849 students in the intervention schools, compared with 3755 and 4247 students in the rest of the province, in 1998 and 2002, respectively. The evaluation of acceptability was based on an analysis of 491 documents generated from 1998 to 2002. The outcomes of effectiveness were specific risks and harmful consequences associated with substance use. We found that harm minimization was an acceptable approach to drug education targeting the senior high school population, and there was also some evidence of effectiveness in that age group in that the prevalence of several risks and negative consequences of substance use decreased significantly in the intervention schools relative to the rest of the province. In junior high school, harm minimization was found to not be an acceptable approach to drug education. This demonstration project provides evidence that school-based harm minimization may be acceptable and effective in senior high schools but may not be acceptable in junior high schools.     

正常人与重症肌无力患者胸腺提取液免疫活性比较

用~３Ｈ－ＴｄＲ掺入法观察不同稀释度的正常人与重症肌无力患者胸腺提取液对健康成人外周血淋巴细胞增殖的影响。实验证实了正常儿童的胸腺功能下降（高浓度Ｐ＜０．０２，余浓度Ｐ＞０．０５），成人胸腺无功能（Ｐ＞０．０５）；并且得出增生型重症肌无力胸腺提取液对ＰＨＡ诱导的人外周血淋巴细胞增殖有促进和抑制双向作用。提示重症肌无力患者的胸腺免疫活性与正常人比较有差异。解释并肯定了手术切除胸腺治疗增生型重症肌无力的作用。     

Comparative PET studies of the kinetics and distribution of cocaine and cocaethylene in baboon brain.

Recent studies have suggested that cocaethylene, an active metabolite of cocaine found in blood and postmortem brain of individuals self-administering cocaine and alcohol, may play a role in the increased toxicity seen when coadministering these 2 drugs. We have used positron emission tomography (PET) and carbon-11 (t1/2:20.4 min) labeled cocaine and cocaethylene to compare the short-term kinetics of cocaine and cocaethylene in baboon brain. The regional uptake of [11C]cocaine cocaethylene in baboon brain. The regional uptake of [11C]cocaine ([11C]COC) and [11C]cocaethylene ([11C]CE), 5-8 mCi and 4-6 micrograms, in baboon brain (n = 7) were similar but clearance from whole brain (global, GL) and from striatum (SR), thalamus (TH), and cerebellum (CB) was slower for cocaethylene. Steady-state distribution volumes (DV) were not significantly different in the striatum but were greater for cocaethylene in the thalamus, cerebellum, and whole brain. Debenzoylation of cocaethylene proceeded at about one-third the rate of cocaine, as determined by in vitro incubation of labeled cocaethylene and labeled cocaine with baboon plasma and with purified horse butyryl-cholinesterase (EC 3.1.1.8). Even though the slower clearance of cocaethylene could lead to longer tissue exposures and potentially accentuated or different physiological effects relative to cocaine, the difference between the 2 drugs is not large. Thus it is more likely that the direct actions of cocaine and alcohol on some organs, rather than cocaethylene, account for this enhanced toxicity.     

中国蒙,汉族酒依赖与醇脱氢酶和醛脱氢酶基因多态性的相关研究

为探讨醇脱氢酶（ＡＤＨ）基因和醛脱氢酶（ＡＬＤＨ）基因多态性与酒依赖患病的相互关系，用耳血干血痕聚合酶链反应、等位基因特异性寡核苷酸探针方法，检测乙醇代谢酶ＡＤＨ和ＡＬＤＨ基因型在我国蒙、汉民族酒依赖与非酒依赖者中分布频率。结果显示在酒依赖组（汉族５２例，蒙族３１例）与正常对照组（汉族４８例，蒙族３５例）之间：汉族的ＡＬＤＨ２基因型频率与等位基因频率的分布差异有非常显著性（Ｐ＜０．０１），而蒙族则表示为ＡＤＨ２基因型频率与等位基因频率的分布差异有非常显著性（Ｐ＜０．０１）。这提示汉族酒依赖的发病与ＡＬＤＨ２基因有关，蒙族则与ＡＤＨ２基因有关。     

重庆地区驾驶员血液中乙醇浓度与驾驶能力的关系

目的　探讨重庆地区驾驶员血液中乙醇浓度 (BAC)和驾驶能力的关系 ,为交通安全立法提供科学依据。　方法　随机选择重庆地区 59名驾驶员志愿者 ,建立饮酒后驾车模型、科学的BAC测定以及驾驶能力评价体系 ,对不同BAC下驾驶能力进行测评。　结果　受试者出现驾驶能力损害时的BAC均数为 685.9mg/L ,最小值 190 .0mg/L ,最大值 152 0 .0mg/L ,总体均数 95%可信区间为 60 2 .4～ 70 9.5mg/L。汉族和土家族间、汉族男性和女性间、2 3～ 3 5岁和 3 6～ 56岁年龄组间差异无显著性意义 (P >0 .0 5) ,而既往饮酒量不同的三个组别间差异有显著性意义 (P <0 .0 5)。随着BAC增高 ,驾驶能力受损人数增加。在 2 0 0 .0mg/L有 3 % (2 / 59)的受试者驾驶能力降低 ,80 0 .0mg/L则达到 68% (40 / 59)。　结论　随着BAC增高 ,重庆地区驾驶员驾驶能力受损人数比例增加 ,出现驾驶能力明显损害时BAC为 60 2 .4～ 70 9.5mg/L ,既往酒量较大人群中该值较高     

鸡矢藤提取物对小白鼠离体子宫的作用

鸡矢藤[Paederia Scandens]提取物0.32mg 加入营养槽内,对小白鼠各期离体子宫的收缩张力、收缩强度、收缩频率以及子宫活动力均有增强作用。与给药前比较,诱导期组分别增加85%、47%、21%和72%;动情期组分别增加70%、77%、41%和41%;非动情组分别增加47%、76%、62%和66%,而且三组间作用无显著性差异。本品还能增强 PGE_2对小白鼠离体子宫的收缩张力、收缩强度、收缩频率以及子宫活动力。与 PGE_2的作用比较,分别增加34%、39%、9%和45%,但收缩频率增加无统计学意义(P>0.05)。上述结果表明,鸡矢藤提取物对小鼠子宫有显著性兴奋作用,而且还能增强PGE_2对小鼠子宫兴奋作用,其机制尚待进一步研究。     

银杏叶提取物中的芦丁含量测定

用紫外分光光度法测定银杏叶提取物中芦丁的含量，结果表明：以６０％丙酮或７０％乙醇提取银杏叶，所得提取物的芦丁含量为３３．２７％～４３．３８％。     

Ethanol and nicotine consumption and preference in transgenic mice overexpressing the bovine growth hormone gene

Transgenic mice overexpressing the phosphoenolpyruvate carboxykinase/bovine growth hormone (PEPCK/ bGH) hybrid gene and normal (nontransgenic) littermate controls (10 males + 10 females/group) were given access to tapwater and an ascending series of concentrations of ethanol (1.0–22.0%), then a similar ascending series of concentrations of nicotine (1.0–40.0 μg/ml), in a two-bottle choice test. Male transgenic mice consumed more and exhibited greater preferences for ethanol and nicotine than control males; transgenic females consumed less and showed lower preferences for ethanol, but not nicotine, than control females. These results suggest that chronic exposure to high levels of bGH may modulate the rewarding effects of ethanol and nicotine in mice in a gender-specific fashion.     

NMR Investigation of the Futile Cycling of Ethanol in Chronic Alcoholic Rats

Weight gain efficiency differences previously reported between alcohol-fed rats and their controls were investigated. Additionally, the futile cycling of ethanol proposed to explain such differences was studied by NMR spectroscopy. Male Sprague-Dawley rats were fed a nutritionally adequate diet containing 36% of the calories as alcohol, and their paired controls were fed an isocaloric diet for 1 f weeks to establish conditions of chronic alcohol feeding. Normalized metabolic efficiencies varied significantly during the initial 2-week period (6.86 ± 0.51 vs. 2.83 ± 0.18 g/kcal × 10⁻²) for control and alcohol-fed groups, respectively, and to a lesser extent over the entire feeding period (6.41 ± 0.78 vs. 4.60 ± 0.27 g/kcal × 10⁻²) for control and alcohol-fed groups, respectively. Alcohol-induced weight gain inefficiency in metabolism has previously been studied and explained by a variety of different biochemical and physiological mechanisms. One possible pathway of energy wastage may occur due to ethanol futile cycling from ethanol to acetaldehyde through the microsomal ethanol oxidation system pathway, and simultaneously from acetaldehyde to ethanol via the ADH pathway. This futile cycle represents a net loss of 6 ATP/cycle, corresponding to the loss of two reducing equivalents (NADH and NADPH). 1H NMR spectroscopy was used to test for this cycling in blood extracts after administration of 1,1-²H₂ ethanol. No futile cycling was detected either during the initial 2 weeks of feeding or after the entire feeding period.