Vitrectomy for idiopathic epiretinal membranes causing macular pucker.

We used vitreous surgery to remove idiopathic epiretinal membranes from the macular area in 70 consecutive cases. The abnormal tissue was successfully removed in each case. Vision improved postoperatively in 61 eyes (87%), remained unchanged in six eyes (9%), and worsened in three eyes (4%). However, at the time of final examination vision was improved in only 47 eyes (67%), primarily because of the occurrence or progression of nuclear sclerosis, which occurred in 38 of 60 phakic eyes (63%). Four preoperative factors were associated with final visual acuity of 20/60 or better: (1) initial vision of 20/100 or better, (2) shorter preoperative duration of blurred vision, (3) thin epiretinal membrane, and (4) absence of traction retinal detachment.     

As2O3处理前后K562细胞基因表达变化的基因芯片检测

目的应用基因芯片研究三氧化二砷(As2O3)处理前后K562细胞基因表达的变化.方法提取As2O3处理前后K562细胞的总RNA,纯化为mRNA后再反转录为cDNA.cDNA经限制性内切酶Sau3AI切割后,cDNA片段分别用Cy3和Cy5标记,与自制的包含348个基因片段的胎盘库芯片杂交.结果杂交结果经扫描和软件分析,发现了11个差异表达的基因片段,其中有3个基因片段与细胞凋亡密切相关.结论我们构建的胎盘库基因芯片可以成功地用于研究药物作用前后基因表达的变化.     

The impact of sequential quality assessment exercises on laboratory performance: the multicentre ECAT Angina Pectoris Study. Report from the European Concerted Action on Thrombosis and Disabilities (ECAT)

As an adjunct to a European multicentre prospective study, five quality assessment (QA) exercises, spanning a period of 2.5 years, were undertaken. In these, fifteen laboratories from eight countries each performed ten haemostatic factor assays. The design of the QA exercises allowed the between-duplicate, between-day and between-laboratory coefficients of variation (CVs) to be calculated. The between-duplicate CV decreased by a factor of one quarter, and the between-day CV by a factor of one third, over the five exercises. The activated partial thromboplastin time (APTT) assay consistently showed the lowest CVs, while there was notable improvement in the between-day CVs for von Willebrand factor related antigen (vWF R:Ag) and factor VIII clotting activity (VIII:C). However, the between-laboratory CV, assessing extent of agreement between the different laboratories, did not apparently improve over the five exercises. Thus, while QA exercises may be very useful in improving the performance of haemostatic assays according to criteria which an individual laboratory can assess, improving agreement on haemostatic assay results between laboratories may be more difficult to achieve.     

Teaching behavioral medicine using individual coronary heart disease risk factors

Two hundred twenty-one first-year medical students participated in a voluntary coronary heart disease risk factor self-change project designed to teach the principles of behavioral change. Blood pressure, serum lipids, percentage body fat, cardiovascular fitness, and smoking status were measured prior to the project. Students designed their own programs of behavior modification and, after 8 weeks, repeat measurements were obtained in students whose projects related to coronary heart disease risk (56% of entire group). Despite generally low initial coronary heart disease risk factors, most risk factor groups successfully altered the targeted risk factors. The subgroup attempting to lower serum cholesterol (n = 49) reduced total cholesterol 15 +/- 24 mg/dl (mean +/- SD) and low-density lipoprotein cholesterol 11 +/- 20 mg/dl (P less than 0.001 for both). The blood pressure group (n = 9) decreased systolic blood pressure 8 +/- 10 mm Hg (P less than 0.05), and the weight-loss group (n = 33) lost 3.0 +/- 2.9 kg (P less than 0.001), reducing estimated percentage body fat 1.7 +/- 1.8 (P less than 0.001). The self-change project was well received by the students and appears to be a useful technique for introducing the principles of behavioral medicine to first-year medical students.     

地塞米松对布比卡因诱导小鼠神经元毒性的影响

Objective To investigate the effect of dexamethasone on the toxicity of bupivacaine in murine neurons.Methods Murine neuroblastoma cell line N2a was obtained from ATCC cell bank (USA). The cells were cultured in 10% fetal cow serum/MEM culture medium and divided into 4 groups voup I control (Con); group II bupivacaine ( Bup); group Ⅲ dexamethasone (Dex) and group IV Dex + Bup. The culture medium contained bupivacaine 900 μmol/L in group Bup and dexamethasone 1 μmol/L in group Dex respectively. In group Dex + Bup ( IV ) Bup was added to the culture medium with a final concentration of 900 μmol/L at 12 h after pretreatment with Dex 1 μmol/L. The cells were inoculated in 24 well plates (0.5 ml in each well, 24 wells in each group) and 10 cm culture dishes (7 ml in each dish, 4 dishes in each group). The release rate of LDH was calculated and the morphology of the cells and nucleus condensation (by Hoechst 3334224 fluorescent staining) was detected at 9 h of incubation in 24 well plates. The mitochondrial transmembrane potential (by JC-1 assay) and phosphorylation of Akt and ERKs (by Western blot) were measured at 5 h of incubation in 24 well plates and in culture dishes respectively. ResultsBupivacaine caused severe damage to the N2a cells as evidenced by increase in LDH release and nucleus condensation (apoptosis), dephosphorylation of Akt and ERKs, decrease in mitochondrial transmembrane potential and severe morphological changes. Dexamethasone pretreatment significantly attenuated bupivacaine-induced neurotoxicity. Conclusion Dexamethasone can protect N2a cells from bupivacaine-induced neurotoxicity through stabilization of mitochondrial transmembrane potential and inhibition of dephosphorylation of Akt and ERKs.     

Agilent 2100 Bioanalyzer在基因差异表达研究中的应用

目的观察Agilent 2100 Bioanalyzer 芯片分析系统(以下简称Bioanalyzer)在基因差异表达研究中的应用。方法应用限制性显示技术分别从正常和热休克处理后的酿酒酵母细胞中分离出cDNA片段,然后再用Bioanalyzer和传统的琼脂糖凝胶电泳技术对RD-PCR产物进行检测分析。结果Bioanalyzer能更快速、敏感地分离和显示差异表达的基因片段,并且通过对差异片段进行定量比较,发现了数个表达有明显差异的基因片段。结论Bioanalyzer在基因差异表达研究中具有重要的应用价值。     

A negative correlation between the induction of long-term potentiation and activation of immediate early genes.

In the present study we examined the relationship between the induction of long-term potentiation (LTP) in the dentate gyrus of anesthetized rats and activation of immediate early genes (IEGs; c-fos and zif/268) using several different high-frequency stimulation paradigms. Stimulation parameters that effectively induced LTP were not associated with IEG activation. Conversely, stimulation parameters that failed to induce LTP consistently resulted in IEG activation. These results suggest that there is a negative correlation between IEG activation and LTP, and that activation of IEGs is neither necessary nor sufficient for the induction of LTP.