高效液相色谱法测定人肝细胞色素P450 3A4转基因细胞中氨氯地平

目的 :研究氨氯地平经人肝细胞色素 P4 5 0 3A4 (CYP3A4 )的代谢 ,建立反相高效液相色谱的测定人肝转基因细胞 CYP3A4酶 S9孵育液中氨氯地平浓度的方法。方法 :与人肝转基因细胞提取的 S9上清液孵育之后的样品 ,用 3倍量的甲醇沉淀后离心 ,取上清液用 0 .4 5μm微孔滤膜滤过后进样。采用 Hypersil C18柱 ,以乙腈 -磷酸盐缓冲液 (4 5∶ 5 5 ,v/ v,p H4 .5 )为流动相 ,普萘洛尔为内标 ,在 2 5 0 nm波长处测定。结果 :氨氯地平浓度在 0 .2～ 30 .0μg/ ml范围内线性关系良好 ,r=0 .9993,方法平均回收率为 (98.2± 2 .4 ) % (n=5 ) ,日内和日间相对标准偏差(RSD)均小于 10 % ,检测限为 2 0 ng/ ml,定量限为 0 .2 μg/ ml(回收率为 10 4 .0 % ,RSD为 11.4 % ,n=5 )。结论 :建立的反相高效液相色谱方法简便、准确 ,可用于研究氨氯地平在人肝 CYP3A4转基因细胞中的代谢。     

精卵孵育时间与活性氧的关系以及对体外受精结局的影响

目的检测长、短时受精受精液中活性氧的不同,分析精卵孵育不同时间对体外受精-胚胎移植结局的影响。方法155例接受常规IVF受精的患者,每人取出的OCCC随机分为两组：A组为短时受精,B组为长时受精。检测受精液中H202、CTA的含量。移植的119名患者随机分为两组,一组60人移植短时受精的胚胎,一组59人移植长时受精的胚胎。结果B组的受精液中H202水平明显高于A组（P〈0．05）,CTA水平明显低于A组（P〈0．05）。B组的多精受精率明显高于A组（P〈0．05）,A组的优胚率明显高于B组（P〈0．05）,两组间的受精率、卵裂率、植入率、临床妊娠率无统计学差异。结论长时受精时,过量的活性氧对卵子及胚胎有不利影响。短时受精在不影响受精率的前提下,可以降低多精受精率,提高优胚率。     

Evaluation of drug interactions with nanofibrillar cellulose

Nanofibrillar cellulose (NFC) (also referred to as cellulose nanofibers, nanocellulose, microfibrillated, or nanofibrillated cellulose) has recently gotten wide attention in various research areas and it has also been studied as excipient in formulation of the pharmaceutical dosage forms. Here, we have evaluated the interactions between NFC and the model drugs of different structural characteristics (size, charge, etc.). The series of permeation studies were utilized to evaluate the ability of the drugs in solution to diffuse through the thin, porous, dry NFC films. An incubation method was used to determine capacity of binding of chosen model drugs to NFC as well as isothermal titration calorimetry (ITC) to study thermodynamics of the binding process. A genetically engineered fusion protein carrying double cellulose binding domain was used as a positive control since its affinity and capacity of binding for NFC have already been reported. The permeation studies revealed the size dependent diffusion rate of the model drugs through the NFC films. The results of both binding and ITC studies showed that the studied drugs bind to the NFC material and indicated the pH dependence of the binding and electrostatic forces as the main mechanism.     

川芎嗪注射液对生理状态下大鼠心室组织中硫化氢分泌的影响

目的:探讨川芎嗪注射液对大鼠生理状态下心室组织中硫化氢(H2S)分泌的影响。方法:将8只Wistar大鼠左、右心室剪碎后分为4组;正常对照组和川芎嗪低剂量组(1.5μg/ml)、川芎嗪中剂量组(15μg/ml)、川芎嗪高剂量组(150μg/ml),每组n=8。用Krebs液作为孵育液,放入37℃恒温水浴箱中振荡孵育4h后,用放射免疫法测定孵育液中H2S的含量。结果:左心室组织,川芎嗪低剂量组H2S含量(0.17±0.03)和川芎嗪中剂量组H2S含量(0.17±0.03)与对照组H2S含量(0.19±0.03)相比,无统计学意义,川芎嗪高剂量组H2S含量(0.14±0.02)明显低于对照组H2S含量(0.19±0.03)(P<0.01)。右心室组织,川芎嗪低剂量组H2S含量(0.60±0.11)和川芎嗪中剂量组H2S含量(0.53±0.11)与对照组H2S含量(0.64±0.13)相比,无统计学意义,川芎嗪高剂量组H2S含量(0.46±0.09)明显低于对照组H2S含量(0.64±0.13)(P<0.01)。结论:在生理状态下,大剂量川芎嗪具有抑制心室组织释放H2S的作用。     

Cytotoxic Activity of CD4+ T Cells against Autologous Tumor Cells

The ⁵¹Cr-release assay is mostly applied to detecting the cytotoxic activity of CD8⁺ T cells, and little is known about the activity of CD4⁺ T cells. Therefore, the correlation between the cytotoxic activity of CD4⁺ or CD8⁺ T cells and the incubation period with autologous tumor cells was analyzed by two methods. The incubation periods were 4 and 20 h (4 h and 20 h assay) for the ⁵¹Cr-release assay. Eight pairs of tumor cells and T cells were assayed. T cells were fractionated into CD4⁺ and CD8⁺ T cells by using magnetic beads and panning methods, and those cells were activated by culture with recombinant interleukin-2 and immobilized anti-CD3 monoclonal antibody. In 6 out of 8 cases, no cytotoxic activity of CD4⁺ T cells was detected by the 4 h assay, whereas cytotoxic activity was detected in all cases in the 20 h assay. The cytotoxic activities in 20 h assay of CD4⁺ T cells were increased 67-fold in comparison with the activities in 4 h assay (range: 5–197). In the case of CD8⁺ T cells, cytotoxic activities were detected in 6 out of 8 cases in the 4 h assay. The lytic unit ratio of CD4⁺ and CD8⁺ T cells was calculated as 1.5 in the 20 h assay (range: 0.2->7.2) versus 0.4 in the 4 h assay (range: < 0.1–1.3). Cytotoxic activities in colorimetric assay using Crystal Violet with a 24 h incubation were similar to those in the 20 h ⁵¹Cr-release assay in all eight cases. These results indicate that CD4⁺ T cells have cytotoxic activity as strong as that of CD8⁺ T cells towards autologous tumor cells.     

含区间数据Gamma分布的参数估计

目的 建立含区间数据Gamma分布的参数估计方法，并用于SARS潜伏期的推算。方法 采用EM算法构造出求解含区间数据Gamma分布参数极大似然估计的迭代公式，并应用于SARS潜伏期分布的拟合。结果 基于EM算法的极大似然估计方法可以计算出含区间数据Gamma分布的两个参数，从而得到均值估计。同时，还可以根据极大似然估计的渐近性质，计算出估计量的标准误及各参数的置信区间。用于中国内地SARS爆发资料分析，发现SARS潜伏期服从Gamma(2．1，2．33)分布；潜伏期均值和方差的极大似然估计值分别为4．89天(95％CI4．43～5．35)和11．40天^2；95％的病人感染SARS-CoV后将在11．42天内发病。结论 基于EM算法的极大似然估计方法对于含区间数据Gamma分布参数的估计是强健的。可以用于含区间数据SARS潜伏期的精确估计。     

1059例狂犬病个案分析及潜伏期影响因素研究

目的调查湖南省狂犬病个案,探讨狂犬病发病和潜伏期的影响因素,为制定狂犬病防制策略提供科学依据。方法收集湖南省2004-2007年1 059份狂犬病个案资料,采用Epidata 3.1软件录入数据库,运用SPSS15.0软件进行单因素(行×列卡方检验)和多因素分析(有序回归、多元线性逐步回归)潜伏期影响因素,用Logistic回归分析暴露后接种狂犬疫苗的影响因素。结果71.39%的病例为农民,95.85%被犬所伤,Ⅱ、Ⅲ度伤占83%,暴露后仅12.94%在医疗机构处理伤口,狂犬疫苗接种率仅15.20%,抗血清使用率4.15%。潜伏期中位数55 d(最短2 d,最长4 636 d);病例的年龄、暴露后是否注射人用狂犬疫苗、暴露部位、动物种类、处理方法、职业均对潜伏期长短有影响。只有暴露部位为头颈部、在县级及以上医疗机构处理与疫苗接种呈正相关,而暴露程度为II度、未进行处理、自行处理或伤口挤压出血、消毒、缝合,与疫苗接种呈负相关。结论加强农村地区重点人群预防狂犬病的健康教育、提高暴露后伤口处理率及免疫接种率是狂犬病防制的主要措施。     

Sensitization to the reinforcing effects of cocaine following binge-abstinent self-administration

The process of addiction in humans involves a transition from recreational drug use to compulsive drug-taking. To understand or study this behavioral phenomenon from a neurobiological perspective, behavioral models that reflect this process are necessary. Data from typical (restricted access) self-administration procedures demonstrate a stable pattern of responding over time, and thus fail to capture the transitional phases of this process. Here we describe the development of a model that incorporates self-administration-induced changes in the reinforcing efficacy of cocaine, assessed using a progressive ratio schedule of reinforcement to probe the ‘motivational’ state of the animal. To date we have identified two necessary conditions for the development of this sensitization: extended access to cocaine and a deprivation period. This model, in conjunction with recently developed tools to characterize neurochemical and epigenetic changes, will provide a better understanding of the neurobiological bases of the addiction process.     

盐城市部分狂犬病毒隐性感染者跟踪观察

[目的]查明检测出的狂犬病毒隐性感染者是否真正的隐性感染者。[方法]2003年,对盐城市部分有暴露史的自愿者进行血清狂犬病毒抗体检测,并于2005年、2006年对其中的抗体阳性者进行随访和抗体消长情况调查。[结果]观察的自愿者均未注射过狂犬病疫苗,222名有暴露史者血清狂犬病毒抗体阳性的45人,其中22人在0.5~6个月前曾被犬、猫等动物致伤,23人与犬、猫等有6个月以上密切接触。2005年复查其中25名狂犬病毒抗体阳性者,10人仍为阳性;2006年检测2005年的4名阳性者,狂犬病毒抗体均为阴性。到2006年12月止,45人均健在;有密切接触史者初次接触时间均在15年以前,动物致伤者的暴露时间为3~5年,分别超过本市狂犬病死亡的最长潜伏期与狂犬病的潜伏期中位数。[结论]检出的狂犬病毒抗体阳性者是真正意义上的隐性感染。