扶正抑瘤颗粒对小鼠H22肿瘤细胞凋亡及p53和Caspase-3基因表达的影响

目的 研究扶正抑瘤颗粒(FYK)对小鼠H22肿瘤细胞生长的抑制作用,及其对细胞凋亡和p53、Caspase-3基因表达的影响。方法 用体内实验观察FYK对H22瘤株的抑瘤率,流式细胞术测定细胞凋亡率和细胞周期,反转录-聚合酶链式反应(RT-PCR)法测定野生型p53(Wtp53)和Caspase-3的mRNA表达情况。结果 12g／kg、24g／kg FYK均能显著抑制小鼠H22肿瘤细胞的生长,最高抑瘤率为51．24％(P<0．01)。流式细胞术检测表明,FYK显著提高H22肿瘤细胞的凋亡率,最高为15．84％(P<0．01);肿瘤细胞阻滞在G0／G1期,S期细胞比率降低;RT-PCR实验表明,FYK可显著上调p53和Caspase-3 mRNA的表达水平。结论 FYK能显著抑制小鼠H22肿瘤细胞生长,其抗肿瘤机制与诱导细胞凋亡,调控细胞周期,促进Wt p53与Caspase-3基因的表达有关。     

Improvement of the Prediction Power of the CoMFA and CoMSIA Models on Histamine H3 Antagonists by Different Variable Selection Methods

The aim of this study is to enhance the predictivity power of CoMFA and CoMSIA models by means of different variable selection algorithms. The genetic algorithm (GA), successive projection algorithm (SPA), stepwise multiple linear regression (SW-MLR), and the enhanced replacement method (ERM) were used and tested as variable selection algorithms. Then, the selected variables were used to generate a simple and predictive model by the multilinear regression algorithm. A set of 74 histamine H₃ antagonists were split into 40 compounds as a training set, and 17 compounds as a test set, by the Kennard-Stone algorithm. Before splitting the data, 17 compounds were randomly selected from the pool of the whole data set as an evaluation set without any supervision, pretreatment, or visual inspection. Among applied variable selection algorithms, ERM had noticeable improvement on the statistical parameters. The r² values of training, test, and evaluation sets for the ERM-MLR model using CoMFA fields were 0.9560, 0.8630, and 0.8460 and using the CoMSIA fields were 0.9800, 0.8521, and 0.9080, respectively. In this study, the principles of organization for economic cooperation and development (OECD) for regulatory acceptability of QSARs are considered.     

Enhancing the Reliability in the Noninvasive Measurement of the His Bundle Magnetic Field Using a Novel Signal Averaging Methodology

Background: Extraction of the weak electrical activity of the “His Bundle” (HB) by noninvasive methods has not been very successful in the past. The study reassesses the use of signal averaged magnetocardiography (SAMCG), overcoming some of the limitations in earlier studies including in the signal averaging methodology. Methods: SAMCG on healthy subjects (14 male and 1 female) were performed using R‐peak as the fiducial point in all cases and also using QRS‐onset as the fiducial point in select cases. Results: A conspicuous feature (H) with a magnitude up to 200 femto Tesla (fT) attributed to the HB activity was observed in the PR segment at several spatial positions on the thorax, with onset at 35–50 ms before the QRS‐onset (V) in 15 out of 18 trials constituting 83% of cases studied. The QRS‐onset as the fiducial point resolved the feature better compared to the conventionally used R‐peak, especially in trials exhibiting spread in heart rate (HR). This is attributed to the fluctuations in Q_onRD (the time interval between QRS‐onset and R‐peak) compared to the temporal stability of the H‐V duration. Conclusions: SAMCG reveals a well‐resolved H feature. The double hump morphology of the feature extended at least up to a frequency of 150 Hz. The importance of the choice of QRS‐onset as the fiducial point is unequivocally demonstrated, illustrated by measurements on subjects exhibiting considerable heart rate variability. The latter has a general validity and should be applicable to SAECG as well.     

The political economy of the public–private mix in heath expenditure: An empirical review of thirteen OECD countries

This study investigates the factors that may have influenced the public–private mix of health expenditure in 13 OECD countries from 1981 to 2007. The degree to which health services are socialized is regarded as the product of a trade-off between the desire to redistribute income through the fiscal system and the losses some citizens will incur when the public health care system expands.     

The changing of the guards : Can family doctors contain worker absenteeism?

Using administrative data from Norway, we examine the extent to which family doctors influence their clients’ propensity to claim sick-pay. The analysis exploits exogenous switches of family doctors occurring when physicians quit, retire, or for other reasons sell their patient lists. We find that family doctors have significant influence on their clients’ absence behavior, particularly on absence duration. Their influence is stronger in geographical areas with weaker competition between physicians. We conclude that it is possible for family doctors to contain sick-pay expenditures to some extent, and that there is a considerable variation in the way they perform this task.     

Genotype-Phenotype Correlation In Iranian Patients With Hb H Disease

Thalassemia is the most common genetic disorder in Iran. Some α-globin genotypes leading to Hb H disease may cause severe anemia and dependence on regular blood transfusions. In this study, 40 patients were analyzed for the molecular basis and the genotype-phenotype correlation of Hb H disease in Iran. α-Globin molecular analysis was performed by polymerase chain reaction (PCR) followed by agarose gel electrophoresis, reverse hybridization test strips or DNA sequencing. The most frequently observed α-globin genotypes were –α^3.7/– –^MED in 10 patients (25%), – –^20.5/α^–5ntα in six patients (15%) and – –^20.5/–α^3.7 in four patients (10%). A subset of the identified Hb H genotypes, including – –^MED/α^CSα, – –^MED/α^PolyA2α and α^CSα/α^CSα, was associated with a need for regular or irregular blood transfusions. Our findings provide a basis for predicting phenotype severity by identifying the Hb H genotype and making more selective decisions for prenatal diagnosis.     

人源H5N1亚型禽流感病毒株空斑特性和致病性研究

目的观察不同H5N1亚型禽流感病毒株空斑特性,对比研究不同空斑类型H5N1病毒致病性和复制能力差异。方法将不同稀释度的H5N1亚型禽流感病毒株分别接种于MDCK单层细胞,加盖营养琼脂,合适时间染色,观察不同H5N1亚型禽流感病毒株空斑形成特点,按照DullbeccoR的方法计算病毒PFU数;根据空斑大小进行挑选、纯化、筛选不同类型空斑病毒,测定这些病毒对Balb/c小鼠致病性差异和在MDCK细胞上复制差异。结果野生的人源H5N1禽流感病毒株在空斑形成上都存在不同程度的不均一性,空斑大小、形状差异明显:A/Vietnam/1194/2004(H5N1)以大圆形斑为主,夹杂少量小点状斑。A/Beijing/01/03(H5N1)大多数为中等大小空斑,并有少数针尖状斑。野生A/Vietnam/1194/2004经过分离纯化后,得到的两种空斑类型病毒在致病性和复制能力存在明显差异。结论野生的人源H5N1禽流感病毒株在空斑形成上都存在不同程度的不均一性,从野生病毒株中分离、纯化的大小斑病毒在致病性和复制能力上存在明显差异。     

H型高血压对非ST段抬高急性冠脉综合征GRACE评分和N-末端脑钠肽的影响

目的：观察 H 型高血压对非 ST 段抬高急性冠脉综合征( NSTE-ACS )患者全球急性冠脉注册事件( GRACE)危险评分和N-末端脑钠肽( BNP)水平的影响。方法高血压合并非ST段抬高急性冠脉综合征患者108例,按照血清Hcy水平分为H型高血压组和对照组。比较2组患者GRACE评分和血浆BNP水平。结果高Hcy组GRACE评分高危组例数较对照组明显增加,中危组例数较对照组降低,低危组例数两组间比较差异无统计学意义( P>0．05)。高Hcy组BNP水平明显高于对照组。结论 H型高血压对非ST段抬高急性冠脉综合征患者的预后有一定的预测价值。