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新生儿重症监护病房便携式广域眼底成像系统早产儿视网膜病变筛查结果分析

Effect of Silencing of Hypoxia Inducible Factor-1 Alpha Gene on Chemosensitivity of Human Hepatocellular Carcinoma Cells and Correlative Mechanisms

【 Abstract 】 Objective To observe the effect of disruption of hypoxia inducible factor-1 α (HIF-1 α ) pathway by small hairpin RNA (shRNA) on chemosensitivity of human hepatocellular carcinoma (HCC) cells and to reveal the correlative mechanisms. Methods Plasmid of pshRNA-HIF-1α was transfected into HepG2 cells by lipofectamine. HepG2/pshRNA-HIF-1α (HepG2/pshRNA) cell lines were obtained by selection of HepG2 cells in G418. Meanwhile, plasmid of empty vector (pHK) was transfected as a control (HepG2/pHK). The mRNA and protein expression levels of HIF-1α and mdr1 were investigated by RT-PCR and Western blot respectively. Using CoCl2 to simulate the hypoxia condition, growth inhibition and apoptosis rates of HepG2 cells under different dosages of chemotherapeutic agents (adriamycin) were measured by MTT assay and flow cytometry (FCM) ． ResultsCompared with HepG2/pHK cells, the mRNA and protein expression levels of HIF-1αand mdr1 were obviously down-regulated in HepG2/pshRNA cells. At the same time, the proliferation inhibition and apoptosis rates were evidently increased after transfection with pshRNA-HIF-1α(P＜0.05)，which decreased the expression of HIF-1αto 82.18% at mRNA level and 75.51% at protein level. There was no significant effect of transfection pHK (Pgt;0.05). Conclusion These data demonstrates that HIF-1α interference by shRNA increased the sensitivity of HCC chemotherapy and the reversal of multidrug resistance, which may be done by down-regulating the transcription of mdr1 and the translation of P-gp. Blocking HIF-1αin HCC cells may offer an new avenue for gene therapy．

The Protective Effects of Ischemic Postconditioning on Ischemiareperfusion Myocardium and the Relationship with Mitochondrial Adenosine Triphosphate Sensitive K+ Channels

Objective To investigate the protective effects of ischemic postconditioning (IPo) on ischemiareperfusion (I/R) myocardium and the relationship with mitochondrial adenosine triphosphate (ATP) sensitive K+ channels (mitoKATP) and provide evidences to the development of druginduced postconditioning. Methods Langendorff models were established in 40 Wistar rats which were divided into 5 groups by random number table with 8 rats in each group. Normal control group(NC group): the rat hearts were continuously reperfused by KrebsHenseleit bicarbonate buffer (K-HB) for 100 min without any other treatment; I/R group: the rat hearts underwent a 40-min global ischemia followed by a 60-min reperfusion; IPo group: after a 40-min global ischemia, the process of 10-second reperfusion followed by a 10-second ischemia was repeated 6 times, then there was a continuous 58min reperfusion; 5-hydroxydecanoic acid(5-HD) group: after a 40min global ischemia, hearts with 5HD(100 μmol/L) K-HB were reperfused for 15min and then perfused without 5HD for 45min；IPo+5-HD group: after a 40-min global ischemia, the process that the isolated hearts with 5-HD(100 μmol/L) KHB were reperfused for 10second followed by a 10second ischemia was repeated 6 times, then the hearts with 5-HD(100 μmol/L) KHB were continuously [CM(159mm]perfused for 13-min followed by reperfusion without 5-HD(100 μmol/L) K-HB for 45-min. The cardiac function,coronary flow(CF), cardiac troponin I(cTnI) content in coronary effluent, the area of acute myocardial infarction (AMI) and myocardial ultrastructure were observed. Results Left ventricular developed pressure(74.3±3.3 mm Hg vs. 57.1±3.3 mm Hg,t=1300, P=0.000),+dp/dtmax(1 706.6±135.6 mm Hg/s vs. 1 313.3±96.2 mm Hg/s,t=6.28,P=0.000),－dp/dtmax(1 132.8±112.1 mm Hg/s vs. 575.7±67.7 mm Hg/s,t=13.48, P=0.000) and CF(6.49±0.30 ml/min vs. 3.70±0.24 ml/min,t=28.6,P=0.000) in IPo group were higher than those in I/R group. Left ventricular enddiastolic pressure(10.9±1.7mm Hg vs. 26.2±1.5 mm Hg,t=－19.21, P=0000)and cTnI content in coronary effluent (0.62±0.01 ng/ml vs. 0.71±0.01 ng/ml, t=-12.00,P=0.000) were lower than those in I/R group; the area of AMI decreased 20.8％ compared with that in I/R group (Plt;0.05). The myocardial protective effect in IPo+5HD group was similar with that in IPo group, but lower than that in IPo group. The electron microscope showed that IPo and IPo+5HD could reduce myocardial fiber damage and mitochondrial damage caused by I/R. Conclusion IPo can protect I/R myocardium, which is achieved mainly by activating mitoK-ATP channels. 

糖尿病视网膜病变免散瞳数码眼底照相筛查

RADIOSENSITIVITY OF RETINOBLASTOMA CELL LINE HXO-Rb44

We have studied the radiosenstivity of retinoblastoma cell [inc: HXO Rb~4,and found that the ceil growth reduced markedly after being treated by 3GyT-ray. From both clone for mation method and MTT assay,we identify that HXO-Rb44 cell is radiosensitive to T-ray.Oxygen can increase the radiosensitivity of HXO-Rb44 cell, but decrease the repair of sublethal damage.Oxygen enchaneement ratio(OER)is 2.77~3.01. （Chin J Ocul Fundus Dis,1994,10:217-219）

Effects of X-Ray Dose on Expressions of MicroRNA-221 and PTEN in Human Colorectal Carcinoma Cells

Objective　To investigate the effects of X-ray dose on the expressions of microRNA-221 （miR-221） and phosphatase and a tensin homolog deleted from chromosome10 （PTEN） in human colorectal carcinoma （CRC） cells. Methods　Human CRC-derived cell line， Caco2， was cultured conventionally. The cells were divided into five groups and exposed to different doses of X-ray （0， 2， 4， 6， and 8 Gy） respectively. The total RNA and protein of the Caco2 cells were extracted after irradiation， and the miR-221 and PTEN mRNA expressions were detected by real-time RT-PCR.Moreover， the protein alteration of PTEN in Caco2 cells was detected by Western-blot analysis. Results　The radiation dose of X-ray significantly affected the expressions of miR-221 and PTEN protein in human Caco2 cells in a dose-depen-dent manner. Moreover， the miR-221 expression level was up-regulated gradually with the increase of irradiation dose， on the contrary， the PTEN protein expression level was down-regulated gradually （P＜0.01）. Conclusion　The radiation dose can affect the miR-221 and PTEN protein expression pattern in CRC cells.

肥大细胞对肠易激综合征影响的研究进展

肠易激综合征（irritable bowel syndrome，IBS）是一种常见的功能性肠道疾病。其患病率呈逐年上升趋势，具有病程长，难治愈，易复发等特征，严重影响患者的生活质量。IBS发病机制尚不明确，目前尚无最佳治疗方案，因此，明确 IBS 的病因和发病机制是治疗 IBS 的首要任务。目前学术界研究表明，肥大细胞显著影响 IBS 的发生发展，其释放的活性物质在 IBS 病理生理变化过程中发挥关键性作用。该文对肥大细胞在 IBS 发生发展中的作用研究进展作一综述，为明确 IBS 发病机制，探索新的治疗靶点及开发新型治疗药物提供有价值的参考依据和新思路。

Analysis of microbiology and antibiotic susceptibility of perioperative urinary tract infection in patients undergoing hip or knee arthroplasty

Objective To explore the microbiological etiology and antibiotic susceptibility of periopertive urinary tract infection (UTI) in patients undergoing hip or knee arthroplasty, so as to provide recommendations for antibiotic treatment. Methods A retrospective review was conducted for patients with perioperative UTI who underwent hip or knee arthroplasty between January 1st, 2013 and October 1st, 2015. Microbiological data and antibiotic susceptibility of bacteria were analyzed. Results A total of 117 strains of bacteria were identified, including 11 types of species. Among the organisms cultured, 86.3% (101 strains) were gram-negative bacteria, in which Escherichia coli was the most common causative organism (70.9%, 83 strains), followed by Klebsiella species (7.7%, 9 strains) and Proteus mirabilis (3.4%, 4 strains). And among the gram-positive bacteria detected, the proportion of Enterococcus faecalis and Feces Enterococcus was 6.8% (8 strains) and 3.4% (4 strains), respectively. The bacteria showed highly resistance to cephalosporins, quinolones and sulfonamides, but showed high sensitive to nitrofurantoin, carbopenems, the enzyme inhibitor complex and aminoglycoside antibiotics. Conclusions There is a diversity of bacteria involved in UTI, and the top 3 pathogens are Escherichia coli, Enterococcus faecalis and Klebsiella species. The resistance rate is high, and nitrofurantoin, amilacin, piperacillin-tazobactam, cefoperazone-sulbactam are the recommended antibiotics to treat the UTI, but the antibiotic should be adjusted according to susceptibility results.

In Vitro Radiosensitivity Study of Head and Neck Squamous Carcinoma Cell SCCⅦ

目的：研究小鼠头颈鳞癌细胞株SCCⅦ体外放射敏感性，并探讨其与细胞周期阻滞的可能关系。方法：利用细胞克隆形成试验及MTT法检测SCCⅦ细胞受X射线照射后细胞存活能力及细胞生长趋势的变化，通过流式细胞学检测X射线照射后细胞周期分布的变化。结果：相同剂量照射后的SCCⅦ细胞存活分数高于Hela细胞（Plt;0.05）；4 Gy照射后的SCCⅦ细胞在96 h内细胞生长速度仍高于Hela细胞（Plt;0.05）；4 Gy照射后SCCⅦ细胞G1期和G2期细胞比例明显升高（Plt;0.05）。结论：SCCⅦ细胞对放射线不敏感性，放射线导致的细胞周期阻滞是SCCⅦ细胞放射抵抗的可能原因之一

糖尿病视网膜病变远程筛查系统应用研究