Inhibition of IgE formation in mice by glycoproteins from corn silk

The inhibitory effects of glycoproteins separated from a hot water extract of corn silk (U-CSE) on the formation of IgE antibodies after primarily and secondarily challenged responses with dinitrophenyl (DNP)-ovalbumin (OVA) antigen in mice were investigated using the passive cutaneous anaphylaxis (PCA) test. When U-CSE was given intranasally or intraperitoneally the day before primary immunization, IgE antibody production was strongly inhibited. Furthermore, it was found that new formation of IgE antibodies was readily inhibited by U-CSE administration in mice with high levels of IgE after primary immunization. It was also found that U-CSE markedly suppressed IgE antibody formation in secondarily challenged responses with the antigen. U-CSE may be clinically applicable to type I allergic diseases.     

粉被虫草提取物对巨噬细胞吞噬功能及CTL活性的影响

研究粉被虫草菌丝体提取物在体外对小鼠腹腔巨噬细胞吞噬功能和脾细胞免疫功能的影响，结果表明：粉被虫草提取物在正常情况下不仅能够促进小鼠腹腔巨噬细胞的吞噬功能，而在免疫抑制的情况下，一定浓度的粉被虫草菌丝体提取物还能恢复提高吞噬功能；它不仅能促进正常脾活化Ｔ细胞的增殖，而且能恢复环磷酰胺和氢化可的松抑制免疫小鼠脾活化Ｔ细胞的增殖；在较高浓度下能增高小鼠脾细胞毒Ｔ淋巴细胞（ＣＴＬ）活性，同时在一定浓度下能恢复免疫抑制小鼠脾ＣＴＬ活性。     

龙眼参提取物对耐药口腔上皮样癌细胞株KB／MIT及耐药乳腺癌细胞株MCF-7／ADR的逆转作用

目的：研究龙眼参提取物XCKB／MIT细胞及MCF-7／ADR细胞株的耐药逆转作用。方法：设计4个不同浓度的龙眼参提取物组，采用MTT方法．测定体外培养的阿霉素敏感株MCF-7及其耐药株MCF-7／ADR以及米托蒽醌敏感株KB及其耐药株KB／MIT的IC50。结果：MCF-7／ADR耐药株及KB／MIT耐药株在龙眼参提取物与阿霉素或米托蒽醌的联合用药中其IC50值分别接近于单独用约于敏感株MCF-7和KB的水平．而与单独用药于耐药株其IC50有显著性差异。结论：龙眼参提取物可以逆转MCF7／ADR和KB／MIT的耐药性。     

Safety assessment of high fructose corn syrup (HFCS) as an ingredient added to cigarette tobacco

A tiered testing strategy has been developed to evaluate the potential for new ingredients, tobacco processes, and technological developments to alter the biological activity that results from burning tobacco. A series of studies was initially conducted with cigarettes containing 3% high fructose corn syrup (HFCS) as an alternate tobacco casing material to corn syrup/invert sugar, including determination of selected mainstream cigarette smoke (MS) constituent yields, Ames assay, sister chromatid exchange (SCE) assay in Chinese hamster ovary (CHO) cells, a 30-week dermal tumor-promotion evaluation of cigarette smoke condensate (CSC) in SENCAR mice, and a 13-week subchronic inhalation study of MS in Sprague-Dawley rats. A second series of studies was conducted with cigarettes containing 3%, 4% and 5% HFCS including MS chemistry, Ames assay, SCE assay in CHO cells, and a neutral red cytotoxicity assays. Collectively, mainstream smoke chemistry, genotoxicity, dermal tumor-promotion, and inhalation toxicity studies demonstrated no differences between cigarettes with 3% HFCS and cigarettes with 3% corn syrup/invert sugar. Also, mainstream smoke chemistry and genotoxicity of cigarettes with 4% and 5% HFCS were not different from cigarettes with 3% HFCS. In conclusion, the addition of up to 5% HFCS to cigarette does not alter the mainstream smoke chemistry or biological activity of mainstream smoke or mainstream smoke condensate as compared to cigarettes with 3% corn syrup/invert sugar with regard to the parameters investigated and presented.     

苏乐康等抑制细胞转化能力及其机制的探讨

研究了苏乐康、绿茶提取物对~(60)钴γ射线和雌性激素联合诱发叙利亚金黄地鼠胚胎细胞恶性转化的抑制能力,并用脉冲辐解技术,对其抑制机制进行初步探讨。实验结果表明,苏乐康、绿茶提取物对γ射线和雌性激素联合诱发的金黄地鼠胚胎细胞恶性转化的抑制率分别为70.15％(P<0.05)和81.59％(P<0.05),它们的这种抑制能力与其清除超氧阴离子的能力有关,     

Progesterone and environmental tobacco smoke act synergistically to exacerbate the development of allergic asthma in a mouse model

BACKGROUND: Asthma affects males and females differently. Females have a higher incidence than males after the onset of puberty. This suggests a hormonal component to the development of the disease. Progesterone, a female hormone, has previously been shown to illicit a T-helper type 2 (TH2) immune response similar to that seen in allergic asthma. Previous studies performed by our laboratory have shown that exposure to environmental tobacco smoke (ETS) enhances the immune response to allergens. OBJECTIVE: To determine if the combination of exposure to ETS and progesterone would further exacerbate the immune response in a mouse model of allergic asthma. METHODS: Female mice were ovariectomized and then implanted with time-release progesterone pellets. Mice were housed in either filtered air (FA) or ETS chambers and half were exposed to aerosolized house dust mite allergen (HDMA). Bronchoalveolar lavage was performed for cell differentials; lung and spleen cells were harvested to compare IL-4 and IFN-gamma production by ELISPOT. RESULTS: Progesterone pellet implantation resulted in increased serum progesterone levels (28.3+/-8.43 vs. 13.5+/-7.22 ng/mL in placebo-treated mice, P<0.0001). Serum total IgE levels were significantly greater in progesterone vs. non-progesterone treated animals that were also exposed to HDMA. ETS exposure enhanced total IgE levels as well. Lung homogenate cells from HDMA/progesterone-treated animals stimulated with Concavalin A produced significantly more IL-4 compared with HDMA/placebo-treated animals (200+/-17.6 vs. 146+/-17.5 spots/well, P<0.01 in ETS exposed animals and 221+/-28.9 vs. 167+/-23.4 spots/well, P<0.01 in animals housed in FA). HDMA/ETS-treated animals had higher eosinophilia in lavage than all other groups. CONCLUSION: Increased serum progesterone levels exacerbate the allergic asthmatic phenotype in a mouse model. These effects are further exacerbated by the addition of environmental tobacco smoke. Progesterone provides a major contribution to the gender differences seen in the development and elicitation of the asthmatic response.     

Ginkgo biloba Extract (EGb 761) Pretreatment Limits Free Radical Oxidative Stress in Patients Undergoing Coronary Bypass Surgery

A growing body of evidence supports the trigger role of free radicals in the delayed functional and metabolic myocardial recovery following cardiopulmonary bypass (CPB) in humans, thus opening the field to specific therapies. This clinical study was designed to evaluate, in 15 patients undergoing aortic valve replacement, whether the extent of CPB- and reperfusion-induced lipid peroxidation, ascorbate depletion, tissue necrosis, and cardiac dysfunction is reduced by orally administered EGb 761, a Ginkgo biloba extract withpotent in vitro antiradical properties. Patients received either EGb 761 (Tanakan, 320 mg/day, n = 8) or a matching placebo (n = 7) for 5 days before surgical intervention. Plasma samples were obtained from the peripheral circulation and the coronary sinus at crucial stages of the operation (i.e., before incision, during ischemia, and within the first 30 minutes post-unclamping), and up to 8 days postoperatively. Upon aortic unclamping, EGb 761 inhibited the transcardiac release of thiobarbituric acid species (p ` 0.05), as assessed by high-performance liquid chromatography, and attenuated the early (5–10 minute) decrease in dimethylsulfoxide/ascorbyl free radical levels, an electron spin resonance index of the plasma ascorbate pool (p ` 0.05). EGb 761 also significantly reduced the more delayed leakage of myoglobin (p = 0.007) and had an almost significant effect on ventricular myosin leakage (p = 0.053, 6 days postoperatively). The clinical outcome of recovery of treated patients was improved, but not significantly, compared with untreated patients. Our results demonstrate the usefulness of adjuvant EGb 761 therapy in limiting oxidative stress in cardiovascular surgery and suggest the possible role of highly bioavailable terpene constituents of the drug.     

焦痂提取液中丙二醛含量对线粒体呼吸及内膜能化作用的影响

大鼠背部20％光辐射Ⅲ度烧伤7天后的焦痂提取液及1:4、1:8稀释液能对正常大鼠肝线粒体呼吸产生明显的抑制作用,相同方法制成的正常皮提取液只呈轻度抑制,1:4稀释液已无抑制作用,两者丙二醛含量相差悬殊,丙二醛含量与抑制率呈相关,但进一步分析表明这种相关为共存现象,丙二醛含量增高不是呼吸率下降的直接原因。丙二醛增高与膜脂双层的破坏有关,内膜能化作用实验表明,当膜脂受到一定程度破坏时,能化作用受到抑制。然而在能化作用未表现异常时,呼吸率已呈一定程度抑制,故呼吸率抑制还受到提取液其他组分的影响。     

Randomised controlled trial of ondansetron in smoking cessation

A double-blind, placebo controlled trial was undertaken to examine the effect of the 5-HT₃ antagonist, ondansetron .25 mg bd on cigarette withdrawal symptoms and on proportion of individuals maintaining continuous abstinence for 4 weeks in a smoking treatment programme. A total of 111 smokers were allocated to active or placebo conditions and began taking their study medication 2 weeks before the quit date. They attended the smokers clinic for weekly group treatment sessions. The results showed no evidence for less severe withdrawal symptoms or improved abstinence rates in the active medication group. They suggest that inhibiting 5-HT₃ activity is not an effective method of controlling nicotine withdrawal or helping smokers to stop.