癫痫大鼠海马结构谷氨酸和nNOS神经元的动态变化

的：探讨谷氨酸(Glu)和一氧化氮(NO)二者在癫痫模型中的作用及其相关性。方法：戊四唑化学点燃癫痫大鼠，分为Ⅰ、Ⅲ、Ⅴ级组和Ⅴ级后24h组。采用免疫组织化学方法和图像分析技术。结果：(1)Ⅲ、Ⅴ级组Glu免疫反应阳性神经元数目和平均光密度值升高；但Ⅴ级比Ⅲ级组有所下降；Ⅴ级后24h组恢复到对照组水平。(2)Ⅴ级组和Ⅴ级后24h组nNOS免疫反应阳性神经元数目和平均光密度值升高。结论：戊四唑点燃癫痫模型中，随着点燃级别的进展，Glu的含量是呈先增加后减少的趋势，而NO的含量是逐渐增加的，提示二者在癫痫发作中既有相关性又有独立性。     

Modification of an <Emphasis Type="Italic">in vivo</Emphasis> Lung Metastasis Model of Hepatocellular Carcinoma by Low Dose N-nitrosomorpholine and Diethylnitrosamine

Previously, we established the in vivo lung metastasis model of rat HCC induced by two hepatocarcinogens, diethylnitrosamine (DEN) and N-nitrosomorpholine (NMOR) at a dose of 120 ppm. This model allows us to investigate modifying factors leading to the inhibition of metastasis formation. However, low survival rates made the evaluation of metastasis formation difficult. The current experiments were conducted to modify the experimental protocol to improve survival and to establish a better animal metastasis model. Lower doses of NMOR (80 or 40 ppm in drinking water) were given to F344 rats for 14 weeks after DEN treatment. Survival rates in the 80 ppm group and in the 40 ppm group were 57% and 81%, respectively and these values were significantly higher than that in 120 ppm. Incidences of lung metastasis in the 40 ppm group steadily increased up to 67% by week 36 while that in the 80 ppm increased sharply up to 86% by week 24. Severity of lung metastases in the 40 ppm group at week 36 was mild compared with the 80 ppm group at week 24. In the second experiment, in order to characterize HCC development and lung metastasis in the 40 ppm group, rats given DEN and then followed with 40 ppm NMOR were killed sequentially. Development of HCC was observed at week 14 and reached 100% incidence at week 20. First lung metastatic lesions were evident at week 22, and incidence of lung metastasis reached 100%. Tumor cells were identified in the blood at week 20 by RT-PCR. The current study revealed that 40 ppm NMOR for 14 weeks after DEN treatment developed HCC without lung metastases at week 22, then HCC with a frequent lung metastasis at week 40. Thus, it can be said that this system is a more appropriate model for elucidation of mechanisms of metastasis and also for analysis of factors to inhibit natural metastasis.     

Pentachlorophenol potentiates benzo[a]pyrene DNA adduct formation in adult but not infant B6C3F1 male mice

The objective of this study is to determine whether pentachlorophenol (PCP) alters benzo[a]pyrene (B[a]P)-induced DNA adduct formation in infant and adult B6C3F1 male mice. Mice were exposed intraperitoneally to 55 microg B[a]P/g body weight (BW) alone and in combination with several doses of PCP in DMSO. The 32P-postlabeling assay was used to analyze for (+/-) anti-7,8-diol-9,10-epoxide-B[a]P-N(2)deoxyguanosine (BPDE-N(2)G) adducts formed in liver and lung DNA. Hepatic DNA also was analyzed for 8-hydroxy-2'-deoxyguanosine (8-OHdG) base damage in mice exposed to PCP. 8-OHdG was not detected at any dose of PCP in infant or adult mice. PCP exhibited an antagonistic effect on BPDE-N(2)G accumulation in infant mice exposed to B[a]P in combination with 50 microg PCP/g BW at both 12 and 24 hr. Comparatively, BPDE-N(2)G adducts were increased in adult mice exposed to binary mixtures at 24 hr in both hepatic and lung DNA (P < 0.05). Multiple comparison analysis between infant and adult mice revealed that adduct levels in infants exposed to B[a]P alone or in combination with PCP were not different from those observed in adult mice exposed to B[a]P. However, a significant increase in adducts was observed in adult mice exposed to a combination of B[a]P and PCP compared to that in all other treatment groups (P < 0.05). These results suggest that PCP alters the metabolism of B[a]P in both infant and adult mice through different mechanisms, and that infants are not susceptible to the potentiating effects of PCP observed in adult mice.     

Cough provocation with capsaicin is an objective way to test sensory hyperreactivity in patients with asthma-like symptoms

BACKGROUND: A group of patients with asthma-like symptoms and sensitivity to chemical irritants, but without bronchial obstruction, has been found among subjects referred for suspected asthma. They have no well-defined diagnosis, and no objective diagnostic method has previously been available. These patients are more sensitive to inhaled capsaicin than are patients with asthma or healthy controls. The aim was to study cough and other capsaicin-induced symptoms and to test the effect of a drug (lidocaine) that inhibits nerve transmission in sensory nerves. METHODS: Twelve patients were provoked with three different concentrations of inhaled capsaicin solutions in a randomized, double-blind order. They all had asthma-like symptoms and were sensitive to chemical irritants, but had no IgE-mediated allergy or demonstrable bronchial obstruction. Before the provocations, the patients inhaled lidocaine or placebo (saline), also in a double-blind, randomized order. The results were expressed as the number of coughs and scores of various symptoms. RESULTS: The patients reacted in a dose-dependent way with cough, airway, and eye symptoms, which were significantly reduced after preinhalation of lidocaine. CONCLUSIONS: A drug that inhibits transmission in sensory nerves successfully blocked the number of coughs and other symptoms provoked by inhalation of capsaicin. This indicates that the mechanisms underlying chemical sensitivity in these patients may originate in the sensory nervous system, and we call this condition "sensory hyperreactivity".     

A scanning electron microscopy study of the interface between ceramics and bone

By use of scanning electron microscopy (SEM), together with energy dispersive chemical analysis, a study has been made of the comparison of an in vitro method of assessing interface reactions between bone and ceramic implants with the naturally occurring changes seen in the rat ear model. Interface reactions between bone and two ceramic materials were examined following 4 wk in culture and 4 wk implantation. In both cases a gradual chemical change occurred at the calcium silicate surface during the fibrous growth onto the ceramic material. Gradual mineralization of the connective fibres was found at the interface of the calcium silicate material, whereas, in the case of alumina ceramic a connective fibrous bond had formed with no associated chemical change at the ceramic surface.     

Optimum support properties for protein separations by high-performance size exclusion chromatography

Optimum chromatographic properties of high performance size exclusion chromatography (HPSEC) of proteins, such as resolution, molecular weight accuracy and recovery, are obtained on packings and columns with tailor-made physical and chemical structures, employed at properly adjusted eluent compositions and operation conditions. SEC-theory suggests that a broad molecular weight fractionation range and high linearity of the log-linear calibration plot can be achieved by the use of two packings (10- and 80-nm pore size, characterized by a pore-size distribution (psd) equal to or less than 1 decade and by equal internal column porosity (p)), rather than a single 30- to 50-nm pore-size packing with a wide psd. Favourably high-phase ratios of (p)/(o)/ 1.0 for HPSEC columns were accomplished with a minimum interstitial column porosity (o) and a high value for the internal column porosity (p) (the specific pore volume, nu(p), multiplied by the packing density, varrho(p).) Ligands such as diol, N-acetoxyamino and oligomeric ether with a propyl- or propoxy-spacer bonded to the silica at the highest density appear to provide high mass recovery and bioactivity as well as chemical stability. Such packings, available in 3-5 mum particle size ranges of narrow distribution, packed into columns 6 mm i.d. and 500 mm in length, offer the best compromise with respect to resolution, speed and pressure drop. More careful studies are required to explain the effects of protein conformational changes and interconversions during elution on HPSEC columns.     

补肾益智方治疗阿尔兹海默病的研究进展

阿尔茨海默病（AD）是最常见的痴呆形式,目前缺少疾病修饰性的治疗药物。中医理论认为肾精亏虚是AD发生发展的内在机制,补肾益精是中医治疗AD的基本原则,贯穿AD治疗的始终。补肾益智方是治疗AD的临床经验方。补肾益智方治疗AD已有大量文献报道,但补肾益智方缺乏临床应用安全性评价,同时其基础研究薄弱,有效成分不明、多靶点作用机制不清。为阐明补肾益智方多成分、多靶点、多途径治疗AD的作用机制,该文综述了补肾益智方治疗AD的研究进展。进一步收集了16个基于高效液相色谱指纹图谱的补肾益智方主要化学成分,并对其成药性与安全性进行评价。利用基于AD重要病理生理学过程的网络药理学与文献综述相结合的方法,深入分析了补肾益智方靶向胆碱能系统、AD神经病理学特征的有效成分及可能机制。该研究为AD对症治疗、疾病修饰性治疗的药物研发提供了一系列有潜力的先导化合物,并为深入拓展补肾益智方的临床应用提供了理论依据。     

补肾生血方联合西药治疗再生障碍性贫血早期疗效预测指标

目的：探讨补肾生血方联合西药治疗再生障碍性贫血（AA）早期疗效的预测指标,为中医补肾治法联合西药治疗AA提供预后参考指标。方法：本研究为回顾性研究,选取2018年9月至2021年3月于中国中医科学院西苑医院等19家医院就诊并采用补肾生血方联合西药治疗6个月有效的126例患者,评价其治疗4个月时的疗效,根据治疗4个月时的疗效评价结果将其分为4个月有效组和4个月无效组,分析比较两组患者治疗前在年龄、性别、疾病分型[包括重型AA(SAA)、非重型AA(NSAA)]、病程、骨髓有核细胞增生程度及基线血象水平[包括白细胞（WBC）、中性粒细胞（ANC）、血红蛋白（HGB）、血小板（PLT）、网织红细胞（RET）]、T淋巴细胞及亚群、T-box转录因子（T-bet）、GATA家族转录因子-3(GATA-3)表达水平指标上的差异。结果：4个月有效组在20岁≤年龄<40岁及60岁≤年龄<80岁患者占比较高（P<0.05）;两组患者在性别、疾病分型（SAA/NSAA）、病程、有无合并症等方面均差异无统计学意义。4个月有效患者治疗前HGB、WBC、ANC、PLT基线水平明显高于治疗4个月...     

地塞米松诱发大鼠卡氏肺孢子虫肺炎实验研究

目的 在地塞米松磷酸钠诱导下建立大鼠卡氏肺孢子虫肺炎的动物模型。方法 将40只雌性SD大鼠随机分为实验组和对照组,前者皮下注射地塞米松磷酸钠,1mg/次,2次/w;后者不做任何处理。观察两组大鼠的发病情况,并每隔3周两组各取5只动物进行病原学检查。结果 实验组大鼠第6周开始发病,肺印片、支气管肺泡灌洗液沉渣中查到卡氏肺孢子虫包囊及滋养体;对照组大鼠无异常表现,病原学检查阴性。结论 在地塞米松磷酸钠诱导下可成功建立大鼠卡氏肺孢子虫肺炎动物模型。     

光纤化学传感器—计算机联用实时在位测定氧氟沙星片体外溶出度

目的：探索一种连续在位测定固体制剂溶出度的新方法和新理论。方法：应用芘丁酸光纤化学传感器和计算机联用在线技术及中国药典（1995版）规定的紫外分光光度法（UV）分别测定氧氟沙星片剂的体外溶出度。结果：在药典规定的测定浓度范围内有良好的线性,相关系数0．9980。方法的日内、日间精密度（RSD）分别为1．18％和1．56％,当信噪比为3时检测限为0．56μg/ml。用中国药典（1995版）规定的紫外分光光度法作对照并进行评价,P＞0．05,显示两种方法所得结果无显著性差异。结论：本法改变传统的取样分析模式,实现了响应快速、准确、灵敏的过程分析。