内皮素、一氧化氮在毛细支气管炎和哮喘患儿中的变化

目的　 探讨血内皮素 (ET)和一氧化氮 (NO)在毛细支气管炎 (毛支 )和婴幼儿哮喘 (哮喘 )中的变化及意义。 方法 　用放射免疫分析法和分光光度比色法分别检测毛支、哮喘患儿急性期和缓解期血ET和NO ,并与正常儿童进行比较。 结果 　血浆ET在毛支组和哮喘组 ,急性期均明显高于正常组 (P均 <0 0 1) ,缓解期均下降 ,与正常组比较无显著差别 (P均 >0 0 5 ) ;两组急性期比较无差别 (P >0 0 5 )。与血浆ET一样 ,血清NO在毛支组和哮喘组 ,急性期均显著高于正常组 (P <0 0 1和P <0 0 5 ) ;缓解期则下降 ,与对照组比无显著差别 ,(P均 >0 0 5 ) ;两组急性期相比 ,差异无显著性 (P >0 0 5 )。两组急性期血浆ET与血清NO呈明显正相关 (P <0 0 5 )。 结论 　在毛支和哮喘中 ,血ET和NO均升高 ,二者关系密切 ,均可能参与毛支及哮喘的发病     

PCR快速鉴定actinobacteria三种模板制备方法的比较

目的 本研究旨在建立准确、简便、快速的放线细菌鉴定技术，为普通和极端环境放线细菌资源的调查和开发利用创造条件。方法 从放线细菌固体培养基上挑取少量菌体，用微波炉法快速制备基因组DNA作为PCR模板，与液体培养法得到的菌体以超声波法或冻融法制备的模板进行了PCR扩增效果的比较研究。结果P CR检测结果表明微波炉法制备的模板可进行有效的体外扩增，目的条带特异，而超声波法或冻融法并不对所有菌株有效，并有非特异扩增产物产生。结论 组合微波炉法快速制备放线细菌基因组DNA技术和23S rRNA特异插入序列PCR扩增技术建立了准确、简便、快速的actinobacteria鉴别体系。     

HPLC法测定复方联苯双酯颗粒中肌苷的含量

目的:应用HPLC色谱法测定复方联苯双酯颗粒中肌苷的含量.方法:采用C8柱以甲醇-水(60:40)为流动相,检测波长为248 nm.结果:肌苷线性范围为2.50～25.00μg·ml-1,r=0.999 97(n=6).肌苷平均回收率100.1%,RSD 0.4%(n=9).结论:方法简便,结果准确,重复性好.     

Profile of non-compliance in lymphoblastic leukaemia

A nationwide study of intracellular drug metabolite concentrations in children prescribed 6-mercaptopurine for the treatment of lymphoblastic leukaemia was carried out to assess interpatient variability at a standardised dose. Nine children (2% of the total) had completely undetectable metabolites, indicative of non-compliance. Five were adolescents, but otherwise they had no obvious distinguishing characteristics. Not taking any 6-mercaptopurine at all is uncommon, but the problem cannot be predicted. The total number of children who do not comply cannot be determined from this study, but the nine children described represent only a fraction of these.     

Kinetic analysis shows that iron deficiency decreases liver vitamin A mobilization in rats

In view of evidence that nutritional status of iron and vitamin A may affect the other nutrient's metabolism, we used model-based compartmental analysis to examine effects of iron deficiency on whole-body vitamin A dynamics in rats. Weanling male Sprague-Dawley rats were fed the AIN93G diet with 2.5 nmol retinyl palmitate/g and either 45 [control (CN)] or 4 microg/g Fe [iron-deficient (ID)] for 8 wk. ID rats consumed food ad libitum; CN rats were food-restricted so that their body weights were the same as ID rats. Two rats/group were killed; liver vitamin A was determined and used for vitamin A balance calculations. [(3)H]Retinol-labeled plasma was administered intravenously to remaining rats, and 27 serial blood samples were collected for 7 wk. At killing, plasma vitamin A was 0.52+/-0.12 (ID, n = 5) vs. 1.34+/-0.12 micromol/L (CN, n = 6; P<0.001), and liver vitamin A was 809+/-94 (ID) vs. 112+/-24 nmol (CN, P<0.001). Plasma tracer data were fit to a three- or four-compartment model using the Simulation, Analysis and Modeling computer program and kinetic parameters were calculated. Vitamin A transfer rate between the retinyl ester storage pool [14+/-3 (ID) vs. 24+/-4 nmol/d (CN), P<0.05] and plasma was lower in ID rats. Vitamin A remained longer in the body [44+/-11 (ID) vs. 22+/-3 d (CN), P<0.05]. Adjusted mean disposal rate was lower in ID (10.0) than CN rats (19.9 nmol/d), as was estimated vitamin A absorption efficiency [58% (ID) vs. 76% (CN)]. Our results suggest that iron deficiency inhibits mobilization of vitamin A stores and may decrease the absorption and irreversible utilization of vitamin A.     

Association of Helicobacter pylori Infection with Gastric Adenocarcinoma

Gastric adenocarcinoma is the most prevalent cancer in South Korea, and Helicobacter pylori (H. pylori) infection is also common. This study was performed to examine the association between H. pylori infection and gastric cancer, taking into account various other factors. To investigate the association between gastric adenocarcinoma and H. pylori infection, determined by urease-positive reaction in the CLO test, a total of 175 paired specimens (175 tumor and 175 tissues adjacent to tumor) of stomach cancer patients and a total of 113 control specimens were obtained. The positive H. pylori infection rates were 78.9% (138/175) among the patients in specimens of tumor or tissues adjacent to the tumor and 41.6% (47/113) among controls in the CLO test. A positive correlation between H. pylori infection and gastric cancer was observed (age-adjusted odds ratio, 7.0; MH χ²=34.5 with P <0.0005). These data suggest that stomach cancer patients in Korea have high infection rates of H. pylori regardless of site specificity, and this infection might be causally associated with stomach cancer.     

N-Ethylmaleimide modulation of tetrodotoxin-sensitive and tetrodotoxin-resistant sodium channels in rat dorsal root ganglion neurons

The effects of N-ethylmaleimide (NEM), an alkylating reagent to protein sulfhydryl groups, on tetrodotoxin-sensitive (TTX-S) and tetrodotoxin-resistant (TTX-R) sodium channels in rat dorsal root ganglion (DRG) neurons were studied using the whole cell configuration of patch-clamp technique. When currents were evoked by step depolarizations to 0 mV from a holding potential of -80 mV NEM decreased the amplitude of TTX-S sodium current, but exerted little or no effect on that of TTX-R sodium current. The inhibitory effect of NEM on TTX-S sodium channel was mainly due to the shift of the steady-state inactivation curve in the hyperpolarizing direction. NEM did not affect the voltage-dependence of the activation of TTX-S sodium channel. The steady-state inactivation curve for TTX-R sodium channel was shifted by NEM in the hyperpolarizing direction as that for TTX-S sodium channel. NEM caused a change in the voltage-dependence of the activation of TTX-R sodium channel unlike TTX-S sodium channel. After NEM treatment, the amplitudes of TTX-R sodium currents at test voltages below -10 mV were increased, but those at more positive voltages were not affected. This was explained by the shift in the conductance-voltage curve for TTX-R sodium channels in the hyperpolarizing direction after NEM treatment.     

Immune responses against SARS-coronavirus nucleocapsid protein induced by DNA vaccine

The nucleocapsid （N） protein of SARS-coronavirus （SARS-CoV） is the key protein for the formation of the helical nucleocapsid during virion assembly. This protein is believed to be more conserved than other proteins of the virus, such as spike and membrane glycoprotein. In this study, the N protein of SARS-CoV was expressed in Escherichia coli DHSalpha and identified with pooled sera from patients in the convalescence phase of SARS. A plasmid pCI-N, encoding the full-length N gene of SARS-CoV, was constructed. Expression of the N protein was observed in COS1 cells following transfection with pCI-N. The immune responses induced by intramuscular immunization with pCI-N were evaluated in a murine model. Serum anti-N immunoglobutins and splenocytes proliferative responses against N protein were observed in immunized BALB/c mice. The major immunoglobulin G subclass recognizing N protein was immunoglobulin G2a, and stimulated splenocytes secreted high levels of gamma interferon and IL-2 in response to N protein. More importantly, the immunized mice produced strong delayed-type hypersensitivity （DTH） and CD^8＋ CTL responses to N protein.