High Expression of Insulin-like Growth Factor H (IGF-Ⅱ) Using Bac-to-Bac Expression System

Objective In order to obtain mature insulin-like growth factor- Ⅱ ( IGF- Ⅱ ), we used Bac-to-Bac baculovirus expression system. Methods Firstly the IGF- Ⅱ cDNA was cloned into a donor plasmid pFastBac1 and the recombinant pFastBac1 was then introduced into competent cells DH 10Bac. Recombinant bacmids were constructed by transposing a mini-Tn7 element from a donor plasmid pFastBac1 to the mini-attTn7 attachment site on the bacmid where the Tn7 transposition functions were provided in trans by a helper plasmid, and then used to transfect Sf9 insect cells to get recombinant baculovirus. The recombinant baculovirus was used to infect insect cells. Results Agarose gel analysis showed that recombinant donor plasmid pFastBac1 was constructed successfully; Agarose gel analysis of PCR products confirmed recombinant bacmid ; SDS-PAGE and Western Blotting showed that a 7KD protein band appeared. Conclusion The mature IGF- Ⅱ with immunogenecity has been expressed and produced by using Bac-to-Bac expression system.     

Role of hydrogen sulfide in subarachnoid hemorrhage

Subarachnoid hemorrhage (SAH) is a common acute and severe disease worldwide, which imposes a heavy burden on families and society. However, the current therapeutic strategies for SAH are unsatisfactory. Hydrogen sulfide (H₂S), as the third gas signaling molecule after carbon monoxide and nitric oxide, has been widely studied recently. There is growing evidence that H₂S has a promising future in the treatment of central nervous system diseases. In this review, we focus on the effects of H₂S in experimental SAH and elucidate the underlying mechanisms. We demonstrate that H₂S has neuroprotective effects and significantly reduces secondary damage caused by SAH via antioxidant, antiinflammatory, and antiapoptosis mechanisms, and by alleviating cerebral edema and vasospasm. Based on these findings, we believe that H₂S has great potential in the treatment of SAH and warrants further study to promote its early clinical application.     

运动对预防老年人跌倒效果的网状Meta分析

目的 系统评价运动对预防老年人跌倒的疗效.方法 检索1980年至2020年7月Web of Science、PubMed、Cochrane Library、中国知网数据库有关运动对预防老年人跌倒的随机对照试验,采用Review Manager 5.3对纳入文献进行质量评价,应用R-Studio和Addis 1.16.6...     

Prevention of acute exacerbation of chronic obstructive pulmonary disease after bronchoscopic lung volume reduction with endobronchial valves

IntroductionBronchoscopic lung volume reduction (BLVR) with endobronchial valves (EBVs) has emerged as an important treatment method for patients with severe chronic obstructive pulmonary disease (COPD). Acute exacerbations of COPD (AECOPD) are a frequent complication following BLVR with EBV. However, there is no consensus on the prevention of AECOPD.ObjectivesOur study aims to compare the outcomes of different prophylactic measures on the occurrence of AECOPD after BLVR with EBV.MethodsWe conducted a multicenter, retrospective study of patients who underwent BLVR with EBV at six different institutions. Emphasis was directed towards the specific practices aimed at preventing AECOPD: antibiotics, steroids, antibiotics plus steroids, or no prophylaxis. Subgroups were compared, and odds ratios (ORs) with corresponding 95% confidence intervals (CIs) were calculated.ResultsA total of 170 patients were reviewed. The rate of AECOPD was 21.2% for the full cohort. Patients who received prophylaxis had a significantly lower rate of AECOPD compared with those who did not (16.7% vs. 46.2%; p = 0.001). The rate was lowest in patients who received antibiotics alone (9.2%). There was no significant difference in the rate of AECOPD between patients who received steroids alone or antibiotics plus steroids, compared with the other subgroups. The OR for AECOPD was 4.3 (95% CI: 1.8–10.4; p = 0.001) for patients not receiving prophylaxis and 3.9 (95% CI: 1.5–10.1; p = 0.004) for prophylaxis other than antibiotics alone.ConclusionsAdministration of antibiotics after BLVR with EBV was associated with a lower rate of AECOPD. This was not observed with the use of steroids or in combination with antibiotics.     

Construction of AP003469.4-miRNAs-mRNAs ceRNA network to reveal potential biomarkers for hepatocellular carcinoma

Studies have reported that the competing endogenous RNA (ceRNA) networks are related to disease progression and prognosis in patients with hepatocellular carcinoma (HCC). The roles and mechanisms of long-chain non-coding RNA AP003469.4 in HCC have remained unclear. Here, we explored the roles of AP003469.4 in HCC progression using bioinformatics, CCK-8, Transwell assay, etc. AP003469.4 targets miRNAs and these target genes were predicted by the LncBase Predicted v.2, miRDB, miRTarBase, and TargetScan databases. Then, AP003469.4-associated ceRNA network was constructed. Biological functions and mechanisms of differentially expressed genes in the ceRNA network were explored using GO and KEGG. Survival analysis and Cox regression analysis were used to screen prognostic genes and construct a prognostic risk model. The results revealed that AP003469.4, with the area under the curve of 0.9048, was highly expressed in HCC tissues. Increased expression of AP003469.4 was an independent risk factor for the dismal prognosis of HCC patients and was associated with the short overall and disease-free survival. Downregulation of AP003469.4 expression inhibited cell proliferation, cycle transition, invasion, and migration, and promoted cell apoptosis. There were 489 differentially expressed target genes in the ceRNA network, which were involved in several pathways, such as the MAPK signaling pathway, cell cycle, and p53 signaling pathway. The risk model was based on the DTYMK, ZFC3H1, CBX2, PKM, TTC26, ATG10, TAGLN2, CD3EAP, SHISA9, SLC1A5, KPNA2, SCML2, E2F7, and SMARCD1, which were the independent risk factors for poor prognosis of HCC patients. In general, interference with AP003469.4 expression might delay the progression of HCC. AP003469.4 related network could help to identify the hub target molecules in HCC progression, which might be candidate biomarkers for evaluating the prognosis of HCC patients.     

转染外源性转化生长因子β1基因对兔髓核细胞凋亡的影响

①目的探讨转染转化生长因子β1(hTGF-β1)基因对兔髓核细胞凋亡的影响,为活化椎间盘细胞功能、预防椎间盘组织退变提供依据.②方法取成年新西兰大白兔5只,将外源性hTGF-β1基因直接注射于L3～4 椎间隙,以注射同样剂量磷酸缓冲液的L4～5作为实验对照.术后3周取出相应椎间盘组织,利用TUNEL免疫荧光组织化学方法观察髓核细胞凋亡情况.应用Vidas图像分析系统进行免疫阳性细胞半定量分析.③结果注射hTGF-β1基因的椎间盘凋亡细胞数明显少于对照组,测得OPTDM值分别为0.002±0.001、0.159±0.041,二者差异有显著性(t=27.83, P<0.01).④结论转染hTGF-β1基因可以明显减少兔椎间盘髓核细胞凋亡的发生.     

中国上海汉族人群NAD(P)H氧化酶p22phox亚基C242T基因多态性与脑卒中相关性

目的:研究NAD(P)H氧化酶p22phox亚基C242T基因多态性与脑卒中的相关性?方法:收集118例脑出血患者?125例脑梗死患者和147例正常对照组,研究对象均来自上海地区汉族人群,3组在年龄?性别构成比?体质指数(BMI)等基线指标均没有明显差异,分别进行血糖?血脂等各项指标的测定,用聚合酶链反应?限制性片段长度多态性分析(PCR－RFLP)和基因测序方法比较其在不同人群中的基因突变频率?结果:脑出血组?脑梗死组CT + TT基因型(9.3%?9.6%)和T等位基因(4.7%?5.2%),均明显高于对照组(2.0%和1.0%,P < 0.05),脑梗死组中发现1例TT基因型,出血组与正常对照组均未发现TT基因型,与基因测序结果一致?采用二分类Logistic回归分析p22phox亚基C242T基因多态性与脑出血的相关性(β = 1.712,OR = 5.537,95%CI:1.120~27.381,P = 0.036),与脑梗死的相关性(β = 1.432,OR = 4.187,95%CI:0.934~18.774,P = 0.061),表明C242T基因多态性可能是脑出血?脑梗死的危险因素?结论:NAD(P)H氧化酶p22phox亚基C242T多态性与脑出血?脑梗死均有一定的相关性,可能是脑卒中的一个危险因素?但与高血压和饮酒等传统危险因素相比,C242T多态性对脑梗死的影响并不显著?     

一种用于噪声估计的改进最小值搜索方法

含噪语音短时功率谱的最小值搜索是噪声估计的基础。为了提高非平稳噪声估计的准确性,减小噪声水平上升时的噪声估计延时,提出了一种同时使用大、小两个搜索窗进行并行搜索的方法,最小值搜索的最终结果由两个并行搜索结果和基于噪声分类的语音存在二值判决共同决定。实验结果表明：对于高度非平稳的噪声,该方法能够有效地减小噪声估计的延时问题,显著提高增强后语音的质量。     

血液中血管内皮生长因子和锰超氧化物歧化酶检测对肺癌的意义

目的 :探讨血液中血管内皮生长因子 (VEGF)及锰超氧化物歧化酶 (Mn -SOD)水平与原发性肺癌的关系。方法 :检测了 5 8例原发性肺癌、38例肺良性疾病、2 5例健康人血液中VEGF含量和Mn -SOD活力。同时测定了 10例原发性肺癌治疗后血液中VEGF和Mn -SOD水平的变化并与治疗前作了对比观察。结果 :与健康人和肺良性疾病相比 ,原发性肺癌患者血液中VEGF含量、Mn -SOD活力均明显升高 (P <0 .0 1) ,VEGF、Mn -SOD的阳性检出率和诊断正确率分别是 86 .2 %、90 .1%和 79.3%、84 .3%。二者对各型肺癌均有较高的检出率 ,VEGF及Mn -SOD水平与肺癌病期进展有关。 10例肺癌患者VEGF及Mn -SOD水平治疗后显著下降 (P <0 .0 1)。结论 :肺癌外周血液中VEGF含量及Mn -SOD活力异常升高 ,可作为肺癌的诊断、鉴别诊断、临床分期及疗效监测的参考指标。