国产实时荧光定量PCR试剂与GeneXpert MTB/RIF检测结核分枝杆菌的对比分析

目的评价国产实时荧光定量PCR(FQ-PCR)试剂与GeneXpert MTB/RIF(简称“GeneXpert”)检测痰标本结核分枝杆菌的临床应用价值,并比较两者的检测效能。方法收集2017年1月至2018年12月于深圳市南山区慢性病防治院就诊的210例疑似肺结核患者的痰标本,同时做涂片镜检、BACTEC MGIT 960(简称“MGIT 960”)培养、GeneXpert和FQ-PCR检测。以MGIT 960培养为参考,比较GeneXpert和FQ-PCR检测的敏感度、特异度、阳性预测值、阴性预测值,比较两者与MGIT 960培养结果的一致性及两者之间的一致性。按照涂片镜检结果分级报告标准,将痰标本分为荷菌量逐步递增的6个组,即阴性组、少量组、+组、++组、+++组、++++组,比较GeneXpert和FQ-PCR检测各个组阈值循环数(Ct值)均值的差异。结果GeneXpert检测的敏感度、特异度、阳性预测值、阴性预测值分别为83.7%(123/147)、87.9%(51/58)、94.6%(123/130)、68.0%(51/75);FQ-PCR检测的敏感度、特异度、阳性预测值、阴性预测值分别为83.7%(123/147)、89.8%(53/59)、95.3%(123/129)、68.8%(53/77)。FQ-PCR、GeneXpert分别与MGIT 960行Kappa检验,一致性分别为85.4%(176/206)和84.9%(174/205),Kappa值分别为0.70、0.66;对GeneXpert和FQ-PCR检测结果行Kappa检验,一致性为92.8%(194/209),Kappa值为0.85。FQ-PCR检测显示,阴性组与少量组的Ct值均值比较[(33.87±5.00)和(27.29±1.30)个],差异有统计学意义(t=5.56,P<0.001);GeneXpert检测分别为(33.32±6.05)和(23.99±3.36)个,差异有统计学意义(t=5.19,P<0.001)。检测涂片阴性标本时,FQ-PCR与GeneXpert检测的Ct值均值[(33.87±5.00)和(33.32±6.05)个]差异无统计学意义(t=0.32,P=0.750);检测涂片阳性(少量组、+组、++组、+++组、++++组)标本时,FQ-PCR检测的Ct值均值[分别为(27.29±1.30)、(27.95±2.85)、(25.88±3.62)、(24.79±2.46)、(22.38±2.72)个]均明显高于GeneXpert检测[分别为(23.99±3.36)、(23.10±4.05)、(20.22±2.81)、(20.31±4.16)、(16.48±2.78)个],差异均有统计学意义(t值分别为2.60、4.71、6.08、3.85、9.02,P值分别为0.030、<0.001、<0.001、<0.001、<0.001)。结论国产FQ-PCR试剂与GeneXpert检测结果一致性较好,对结核病大规模筛查、降低检测成本具有临床应用价值。

Expression of Nonfusion Extracellular Porcine Zona Pellucida Protein 3β in E.coli

Objeetive To obtain the recombinant non fusion extracellular porcine zona pellucida protein 3β （pZP3β） in E.coli Methods By modificated the transition initiation region （TIR） in primers, synthetic nucleotide was gained by PCR. Such gene was cloned into pET-3c vector and transformed into E.coli BL21（DE3）pLysS. Results The recombi.ant nonfusion extracelhtlar pZP3β was expressed in E.coli to 10% of total cellular proteins, and identified by the Western blot method. Conclusion Modification of nucleotide without changing amino acid sequences is an effective means to increase non fusion expression rate of recombinant proteins, such as pZP3β in E. coll.

Expression of miR-195 in intrauterine adhesion and its relationship with TGF-β1/Smads and FGF2/FGFR1/ERK pathways

Objective:To investigate the expression of miR-195 in intrauterine adhesion(IUA)and its relationship with TGF-β1/Smads and FGF2/FGFR1/ERK pathways.Methods:118 cases of IUA patients who underwent hysteroscopic treatment in our hospital between September 2017 and February 2019 were regarded as IUA group,80 cases of dysfunctional uterine bleeding patients who underwent hysteroscopic curettage in our hospital during the same period were regarded as control group.Differences in the expression levels of miR-195 as well as TGF-β1/Smads and FGF2/FGFR1/ERK signaling pathway-related molecules in the focal tissues obtained by hysteroscopy were compared between the two groups.Pearson test was used to evaluate the correlation of miR-195 expression in the intrauterine adhesion tissues with TGF-β1/Smads and FGF2/FGFR1/ERK pathways in IUA patients.Results:miR-195 expression in intrauterine adhesion tissues of IUA group was higher than that in endometrial tissues of control group(P<0.05).TGF-β1,Smad2 and Smad3 mRNA expression in intrauterine adhesion tissues of IUA group were higher than those in endometrial tissues of control group;FGF2,FGFR1 and ERK mRNA expression in intrauterine adhesion tissues were higher than those in endometrial tissues of control group(P<0.05).Pearson test showed that the miR-195 expression in intrauterine adhesion tissues of IUA group was positively correlated with the TGF-β1/Smads pathway-related molecules TGF-β1,Smad2 and Smad3 mRNA expression,and positively correlated with the FGF2/FGFR1/ERK pathway-related molecules FGF2,FGFR1 and ERK mRNA expression(P<0.05).Conclusion:miR-195 is highly expressed in IUA lesion tissues and may promote disease progression by activating TGF-β1/Smads and FGF2/FGFR1/ERK signaling pathways.

Surgical exposures of the distal humeral fractures: An anatomical study of the anterior, posterior, medial and lateral approaches

Purpose:Exposure of the articular surface is the key to the successful treatment of intra-articular fractures of distal humerus. Anterior, posterior olecranon osteotomy as well as medial and lateral approaches are the four main approaches to the elbow. The aim of this study was to compare the exposure of distal articular surfaces of these surgical approaches.Methods:Twelve cadavers were used in this study. Each approach was performed on six elbows according to previously published procedures. After completion of each approach, the exposed articular surfaces were marked by inserting 0.5 mm K-wires along the margins. The elbow was then disarticulated and the exposed articular surfaces were painted. The distal humeral articular surfaces were then closely wrapped using a piece of fibre-glass screen net with meshes. The exposed articular surfaces and the total articular surfaces were calculated by counting the number of meshes, respectively.Results:The average percentages of the exposed articular surfaces for the anterior, posterior olecranon osteotomy, medial and lateral approaches were 45.7% ± 2.0%, 53.9% ± 7.1%, 20.6% ± 4.9% and 28.5% ± 6.3%, respectively.Conclusion:The anterior and posterior approaches provide greater exposures of distal humeral articular surface than the medial and lateral ones in the treatment of distal humeral fractures.

Improved Fertility Following Enucleation of Intramural Myomas in Infertile Women

Background：The relationship between intramural myomas and fertility remains unclear.The main debate rests on whether cavity-distorting intramural lnyomas （CDMs） adversely affect fertility more than non-CDMs.We aimed to compare the effects ofenucleating non-CDMs and CDMs on fertility improvement in females with unexplained infertility.Methods：We prospectively recruited 83 women undergoing myomectomy for unexplained infertility with intramural myomas between June 2008 and November 2012 and classified them into non-CDMs group （n =45） and CDMs group （n =38）.We then compared postoperative infertility rates,spontaneous pregnancy rates,pregnancy outcomes,live birth rates,and obstetric complications.For continuous variables,we calculated the mean ± standard deviation,median and interquartile range,and analyzed the data using Student＇s t-test and the Mann-Whitney U-test.For categorical variables,the Pearson＇s Chi-square test,the continuity correction test,and Fisher＇s exact test were used.Results：Patients＇ demographics and myoma characteristics were comparable between the two groups.The overall spontaneous pregnancy rate increased from 0% to 68.42% following myomectomy.The postoperative infertility rate was significantly higher in the non-CDMs group than that in the CDMs group （50.00% vs.23.53%,t =5.579,P =0.018）,whereas the postoperative spontaneous pregnancy rate was significantly lower in the non-CDMs group than that in the CDMs group （47.62% vs.70.59%,t 4.067,P =0.044）.Compared with the enucleation ofnon-CDM,the enucleation of CDM patients was a protective factor for the fertility restoration （risk ratio [RR] =3.717,95% confidence interval [CI]：1.284-10.753,P =0.015）,although postoperative fertility restoration declined with age （RR =1.141,95% CI：1.005-1.295,P =0.041）.Conclusions：Intramural myomas are associated with impaired fertility.Women experiencing unexplained infertility,and possessing intramural myomas,have a better chance of conception following myomectomy,and these benefits are more obvious for younger patients and patients with CDM.

A Score Type Test for General Autoregressive Models in Time Series

This paper is devoted to the goodness-of-fit test for the general autoregressive models in time series. By averaging for the weighted residuals, we construct a score type test which is asymptotically standard chi-squared under the null and has some desirable power properties under the alternatives. Specifically, the test is sensitive to alternatives and can detect the alternatives approaching, along a direction, the null at a rate that is arbitrarily close to n-1/2. Furthermore, when the alternatives are not directional, we construct asymptotically distribution-free maximin tests for a large class of alternatives. The performance of the tests is evaluated through simulation studies.

Human umbilical cord Wharton’s jelly-derived mesenchymal stem cell transplantation could improve diabetic intracavernosal pressure

Mesenchymal stem cells(MSCs)secrete various cytokines with angiogenic and neuroprotective effects.This study aimed to assess the effects of human umbilical cord Wharton’s jelly-derived MSCs(hWJ-MSCs)on diabetes-related intracavernosal pressure(ICP)impairment in rats.hWJ-MSCs were isolated from human umbilical cord Wharton’s jelly and transplanted into the corpus cavernosum of streptozotocin(STZ)-induced diabetic rats by unilateral injection.The erectile function was evaluated at 4 weeks,as well as the expression levels of vascular endothelial growth factor(VEGF),basic fibroblast growth factor(bFGF),endothelial nitric oxide synthase(eNOS),and insulin-like growth factor 1(IGF1).STZ-induced diabetic rats showed impaired ICP,which was significantly improved by hWJ-MSC treatment.VEGF,eNOS,IGF1,and bFGF expression levels were higher in hWJ-MSC injection sites than those in control ones in STZ-induced diabetic rats.These results suggest that hWJ-MSC transplantation might improve diabetic erectile dysfunction through increased production of paracrine growth factors,highlighting a novel potential therapeutic option for erectile dysfunction.

Testing for Serial Correlation in Three-dimensional Panel Data Models

This paper studies serial correlation testing for a general three-dimensional panel data model. As a step for hypothesis testing, the robust within estimation of parameter coefficients is investigated, and shown to asymptotically consistent and normal under some mild conditions. A residual-based statistic is then constructed to test for serial correlation in the idiosyncratic errors, which is based on the parameter estimates for an artificial autoregression modeled by centering and differencing residuals. The test can be shown to asymptotically chisquare distributed under the null hypothesis. Power study shows that the test can detect local alternatives distinct at the parametric rate from the null hypothesis. The test needs no distribution assumptions of the error components, and is robust to the misspecification of various specific effects. Monte Carlo simulations are carried out for illustration.

A Note on Parameter Estimations of Panel Vector Autoregressive Models with Intercorrelation

This note considers parameter estimation for panel vector autoregressive models with intercorrelation. Conditional least squares estimators are derived and the asymptotic normality is established. A simulation is carried out for illustration.

A Modified Residual-based Test for Serial Correlation in Linear Panel Data Models

This paper suggests a modified serial correlation test for linear panel data models, which is based on the parameter estimates for an artificial autoregression modeled by differencing and centering residual vectors. Specifically, the differencing operator over the time index and the centering operator over the individual index are, respectively, used to eliminate the potential individual effects and time effects so that the resultant serial correlation test is robust to the two potential effects. Clearly, the test is also robust to the potential correlation between the covariates and the random effects. The test is asymptotically chi-squared distributed under the null hypothesis. Power study shows that the test can detect local alternatives distinct at the parametric rate from the null hypothesis. The finite sample properties of the test are investigated by means of Monte Carlo simulation experiments, and a real data example is analyzed for illustration.