Magnetic Iron Oxide Nanoparticles Mediated Gene Therapy for Breast Cancer-An In Vitro Study

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), also designated as Apo-2 ligand, is a typical member of the structurally related tumor necrosis factor (TNF) ligand family. It has been shown that TRAIL only induces the apoptosis of cancer cells rather than normal cells. This characteristic offers a new target for cancer treatment[1]. In fact, TRAIL gene has been successfully used for the treatment of cancer[2]. Viruses have been the common vectors used in TRAIL gene t…     

健脾益肾中药对接受灌注化疗肺肿瘤患者近期疗效影响

[目的]观察健脾益肾中药对接受灌注化疗肺肿瘤患者治疗效果的影响。[方法]收集中晚期肺肿瘤患者71例,分为2组。对照组采用单纯局部灌注化疗,以Seldinger氏法穿刺插管,将导管选择至供应肿瘤的支气管动脉局部灌注化疗药物。治疗组采用局部灌注化疗加用中药治疗。[结果]对照组共进行109次治疗,每例平均2.9次,有效率为43.24%。治疗组共进行134次治疗,每例平均4.3次,有效率为73.53%。两组比较有统计学意义(P<0.05)。一般临床症状均有不同程度改善。[结论]中药配合局部灌注化疗治疗中晚期肺肿瘤明显优于单纯局部灌注化疗,两者优势互补,可取得更好治疗效果。     

外周血淋巴细胞/单核细胞比值、中性粒细胞/淋巴细胞比值与EGFR突变肺癌及其转移的相关性研究

目的 探讨初诊为肺癌时的外周血淋巴细胞/单核细胞比值（lymphocyte/monocyte ratio,LMR）、中性粒细胞/淋巴细胞比值（neutrophil/lymphocyte ratio,NLR）与表皮生长因子受体（epidermal growth factor receptor,EGFR）突变阳性及其转移的相关性。方法 回顾性分析301例、348例的肺癌EGFR突变阳性、阴性患者的基本临床特征及炎性指标。观察炎性指标在不同EGFR突变状态、转移状态的差异,用受试者工作特征（receiver operating characteristic,ROC）曲线评价其能否作为鉴别EGFR突变及转移的临床指标。结果 在肺癌EGFR突变患者中女性、未吸烟、腺癌分别占61.8%、75.1%、92.4%。与阴性比较,EGFR突变阳性患者的LMR值明显升高,取界值为2.88时,其敏感度、特异性分别为64.7%、为56.6%。与未发生远处转移患者比较,NLR值在EGFR突变的远处转移患者中明显升高,当界值在2.14时,敏感度为74.7%,特异性为64.0%。NLR与EGFR突变阳性肺癌患者的TNM分期分别呈正相关,LMR则相反。NLR与EGFR突变阳性的肺癌患者的骨转移、脑转移、肿瘤指标如CEA、CA125之间存在显著相关性。结论 肺癌EGFR突变常见于女性未吸烟腺癌特征,LMR、NLR在鉴别EGFR突变及远处转移具有参考价值。     

Construtcion of Neisseria Gonorrhoeae Porin B Plasmid Recombinant and Its Expression in E. coli

A prokaryotic expression recombinant plasmid pET-PIB to express porin B (PIB) of Neisseria gonorrhoeae in E. coli DE3 was constructed in order to provide a basis of research in detection, prophylactic and therapeutic vaccine against the pathogen infection. The gene encoding PIB was amplified by PCR from Neisseria gonorrhoeae and cloned into prokaryotic expression plasmid pET-28a( ) to construct a pET-PIB recombinant, which was verified by restriction endonuclease and DNA sequencing. Protein PIB was expressed in E. coli DE3 induced with IPTG. The antigenicity of the expressed protein was evaluated by indirect ELISA. Rabbits were immunized with the protein and serum was collected after immunization. To assess the immunogenicity of the protein, the titer of serum to protein PIB was determined by ELISA. DNA sequence analysis showed that the nucleic acid sequence of PIB gene was 99.28 % of homology compared with that (NGPIB18) published in GenBank. A 41 kD fused protein was detected by SDS-PAGE and was proven to have reactivity with anti-PIB polyclonal antibody from mouse. A polyclonal antibody to PIB of 1：4000 titer determined by indirect ELISA was obtained from rabbit immunized with the purified product. Recombinant plasmid encoding PIB of Neisseria gonorrhoeae was constructed. Protein PIB with antigenicity and immunogenicity was successfully expressed.     

Biomechanical Comparison of Two Kinds of Internal Fixation in a Type C Zone II Pelvic Fracture Model

Background:

Unstable pelvic fractures are complex and serious injuries. Selection of a fixation method for these fractures remains a challenging problem for orthopedic surgeons. This study aimed to compare the stability of Tile C pelvic fractures fixed with two iliosacral (IS) screws and minimally invasive adjustable plate (MIAP) combined with one IS screw.

Methods:

This study was a biomechanical experiment. Six embalmed specimens of the adult pelvis were used. The soft tissue was removed from the specimens, and the spines from the fourth lumbar vertebra to the proximal one-third of both femurs were retained. The pubic symphysis, bilateral sacroiliac joints and ligaments, bilateral hip joints, bilateral sacrotuberous ligaments, and bilateral sacrospinous ligaments were intact. Tile C pelvic fractures were made on the specimens. The symphysis pubis was fixed with a plate, and the fracture on the posterior pelvic ring was fixed with two kinds of internal fixation in turn. The specimens were placed in a biomechanical machine at a standing neutral posture. A cyclic vertical load of up to 500 N was applied, and displacement was recorded. Shifts in the fracture gap were measured by a grating displacement sensor. Statistical analysis used: Paired-samples t-test.

Results:

Under the vertical load of 100, 200, 300, 400, and 500 N, the average displacement of the specimens fixed with MIAP combined with one IS screw was 0.46, 0.735, 1.377, 1.823, and 2.215 mm, respectively, which was significantly lower than that of specimens fixed with two IS screws under corresponding load (P < 0.05). Under the vertical load of 500 N, the shift in the fracture gap of specimens fixed with MIAP combined with one IS screw was 0.261 ± 0.095 mm, and that of specimens fixed with two IS screws was 0.809 ± 0.170 mm. The difference was significant (P < 0.05).

Conclusion:

The stability of Tile C pelvic fractures fixed with MIAP combined with one IS screw was better than that fixed with two IS screws.     

固相柱水解和IC-H柱中和法制备18F-FDG及放射性损失分析

目的　研究固相柱水解和氢离子交换柱（IC-H）中和法自动化合成2-¹⁸F-β-D-脱氧葡萄糖(¹⁸F-FDG)的方法, 并分析合成过程中的放射性损失。方法　经可调节的风浴加热反应管, 分两次共沸除体系中的水,加入前体2-三氟甲基磺酰基-β-D-甘露糖,亲核反应270 s,风浴冷却,用水将¹⁸F-FDG-OAc₄中间体负压转移到Sep-Pak C₁₈固相水解柱上,冲洗C₁₈柱;NaOH慢慢加入到C₁₈柱床上, 室温下反应;将¹⁸F-FDG转移, 经IC-H柱、Al₂O₃柱、C₁₈柱纯化后收集于产品瓶。结果　合成¹⁸F-FDG全过程只需22 min,不校正合成效率(EOS)为(66.9±4.0)% (n=15),产品pH值为6.0左右,经TLC检测,放射性化学纯度>98%。废液,IC-H柱、Al2O3柱、C₁₈纯化柱,C₁₈水解柱,无菌滤膜等都有不同程度的放射性损失。结论　固相柱水解和IC-H柱中和法自动化合成¹⁸F-FDG,方法简单高效。     

Determination of inhibitory activity of Salvia miltiorrhiza extracts on xanthine oxidase with a paper-based analytical device

A novel paper-based analytical device (PAD) was prepared and applied to determine the xanthine oxidase (XOD) inhibitory activity of Salvia miltiorrhiza extracts (SME). First, polycaprolactone was 3D printed on filter paper and heated to form hydrophobic barriers. Then the modified paper was cut according to the specific design. Necessary reagents including XOD for the colorimetric assay were immobilized on two separate pieces of paper. By simply adding phosphate buffer, the reaction was performed on the double-layer PAD. Quantitative results were obtained by analyzing the color intensity with the specialized device system (consisting of a smartphone, a detection box and sandwich plates). The 3D-printed detection box was small, with a size of 9.0 cm × 7.0 cm × 11.5 cm. Color component G performed well in terms of linearity and detection limits and thus was identified as the index. The reaction conditions were optimized using a definitive screening design. Moreover, a 10% glycerol solution was found to be a suitable stabilizer. When the stabilizer was added, the activity of XOD could be maintained for at least 15 days under 4 °C or −20 °C storage conditions. The inhibitory activity of SME was investigated and compared to that of allopurinol. The results obtained with the PAD showed agreement with those obtained with the microplate method. In conclusion, the proposed PAD method is simple, accurate and has a potential for point-of-care testing. It also holds promise for use in rapid quality testing of medicinal herbs, intermediate products, and preparations of traditional Chinese medicines.     

Prevalence of Vitamin B12 deficiency in elderly population (>60 years) presenting with dementia to outpatient department

BackgroundVitamin B12 deficiency is an easily treatable cause of reversible dementia. It is likely to be more common in Indian population due to traditionally vegetarian culture. This study was conducted to estimate the prevalence of Vitamin B12 deficiency in elderly patients (>60 years) with dementia attending outpatient department.MethodsThis study was conducted in two phases. The first phase was a cross sectional observational study to estimate the prevalence of Vitamin B12 deficiency in the elderly population with dementia. The second phase was a pilot study done in subjects with Vitamin B12 deficiency to assess the change in cognition following Vitamin B12 supplementation.ResultsOut of 2920 study eligible subjects, 200 were diagnosed as dementia with Mini Mental Status Examination (MMSE) score of ≤ 24. Vitamin B12 deficiency was seen in 7.5% of patients. Vitamin B12 deficiency was associated with shorter and more severe dementia. Macrocytosis was more common in Vitamin B12 deficiency (p value < 0.001) where as vegetarian diet did not show significant correlation (p value 0.69). There was significant improvement in the median MMSE score in the intervention group with increase in MMSE by 2 points at 6-8 weeks and 3 points at 12 weeks (p value 0.009 and 0.003 by Mann Whitney test).ConclusionPrevalence of Vitamin B12 deficiency in dementia was 7.5%. It was associated with macrocytosis, shorter duration and more severe dementia. There was a significant improvement in median MMSE score at 6 weeks and 12 weeks following Vitamin B12 supplementation.     

Evolution of insulin resistance in coronary artery disease patients on four different pharmacological therapies

The objective of the study was to examine the evolution of insulin sensitivity in a group of patients with stable coronary artery disease receiving one of four different pharmacological therapies. Insulin sensitivity was evaluated using an insulin suppression test in 40 newly diagnosed patients with coronary artery disease and no previous history of metabolic disorders, who were not taking any medication which might affect insulin sensitivity. The insulin suppression test consisted of a constant infusion of glucose, insulin and somatostatin for 150 min; insulin resistance was estimated by determining the steady-state plasma glucose concentrations during the last 60 minutes of the test. The insulin sensitivity index was calculated by the formula: insulin sensitivity index = (glucose infusion rate/steady state plasma glucose concentrations) × 10³. A second insulin suppression test was performed after 6 months'' therapy with either isosorbide mononitrate, atenolol, diltiazem or captopril in 30 of the 40 patients.
  There were no differences between any of the groups before therapy was initiated. After 6 months, patients treated with captopril and, to a lesser extent, those treated with diltiazem showed statistically significantly decreased steady state plasma glucose concentrations and increased insulin sensitivity index compared to basal values. No statistically significant differences were found in the other two groups. We conclude that captopril and, to a lesser extent, diltiazem improve insulin sensitivity in patients with stable coronary artery disease.


     

Imbalance of endogenous homocysteine and hydrogen sulfide metabolic pathway in essential hypertensive children

Background  Hypertension is a common disease of the cardiovascular system. So far, the pathogenesis of primary hypertension remains unclear. The elaboration of its pathogenesis is an important topic in the field which calls for urgent resolution. The aim of this study was to probe into the metabolic imbalance of homocysteine (Hcy) and hydrogen sulfide (H₂S) in children with essential hypertension, and its significance in the pathogenesis of essential hypertension.
Methods  Twenty-five children with essential hypertension and 30 healthy children with normal blood pressure were enrolled in the study. The medical history was investigated and a physical examination was conducted on the subjects. Plasma Hcy content was examined by fluorescence polarization immunoassay (FPIA). The plasma H₂S level was detected by a modified method with a sulfide electrode. Data were presented as mean±standard deviation. The t test was applied to the mean values of both groups. Pearson linear correlation analysis was applied to the plasma Hcy and H₂S as well as to the systolic pressure against the plasma H₂S/Hcy ratio.
Results  Plasma Hcy, an intermittent metabolite of the endogenous methionine pathway, was markedly increased but plasma H₂S, a final product of this pathway was significantly decreased in hypertensive cases when compared with normal subjects ((Hcy: (12.68±9.69) µmol/L vs (6.62±4.79) µmol/L (t=2.996, P<0.01); H₂S: (51.93±6.01) µmol/L vs (65.70±5.50) µmol/L) (t=-8.670, P<0.01)). The ratio of plasma H₂S/Hcy in children with hypertension was 5.83±2.91, while that of the control group was 11.60±3.30, and the difference is significant with a t=-6.610 and P<0.01. A negative correlation existed between plasma Hcy and H₂S concentrations, r=-0.379, P<0.05. And a negative correlation was found between systolic blood pressure and the plasma H₂S/Hcy ratio, r=-0.687, P<0.05.
Conclusion  There was a metabolic imbalance of homocysteine and hydrogen sulfide in essential hypertensive children.

     

miR-34a通过靶向调控Notch1表达影响乳腺癌细胞的增殖

目的探讨miR-34a通过靶向调控Notch1表达影响乳腺癌细胞的增殖。方法乳腺癌细胞MCF-7转染miR-34a mimics及miR-34a NC,RT-PCR法检测细胞中miR-34a表达,MTT,克隆形成实验,Hoechst染色及流式细胞术分别检测miR-34a mimics对乳腺癌MCF-7细胞活力、克隆能力、凋亡情况及细胞周期的影响;通过双荧光素酶报告基因实验,western blot及RT-PCR检测Notch1是否是miR-34a的下游靶基因。结果与miR-34a NC比较,miR-34 mimics组中miR-34a表达量上调,细胞活力降低(P0.01),细胞凋亡率显著提高(P0.01),细胞克隆数目减少(P0.01),细胞周期阻滞在G1期(P0.01),Notch1蛋白及mRNA表达量都显著降低(P0.01),同时荧光素酶报告基因实验也证实miR-34a mimics能与报告基因结合。结论 miR-34a mimics能通过负性调控Notch1表达,从而显著的抑制MCF-7乳腺癌细胞增值,并诱导细胞凋亡。     

Factors relating to bone mineral density in young and middle-aged patients with ankylosing spondylitis

Background:Ankylosing spondylitis (AS) is a common chronic progressive rheumatic disease. The aim of this study was to explore factors influencing abnormal bone mineral density (BMD) in young and middle-aged patients with AS.Methods:From July 2014 to August 2018, hospitalized patients with AS and health examinees in the health examination center of our clinics, ranging in age from 20 to 50 years, were monitored. The BMD of the lumbar spine and femoral neck of AS patients and those of a healthy control group were measured using dual-energy X-ray absorption. The BMDs of AS patients were compared with respect to age, course of disease, iritis, smoking habits, sex, height, weight, body mass index (BMI), medication use, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), platelet volume, platelet count, uric acid (UA), alkaline phosphatase (AKP), and calcium ion levels. Single-nucleotide polymorphisms (SNPs) related to BMD were screened using genome-wide association analysis.Results:There was no statistical difference in the proportion of abnormal bone masses between the different body parts. The BMD of all bones in AS patients was lower than that in healthy controls (P < 0.05). Additionally, BMD was correlated with serum calcium and CRP in AS patients (P < 0.05), but not with age, platelet volume, platelet count, ESR, UA, AKP, height, weight, and BMI. The incidence of abnormal bone mass in AS patients was correlated with sex (P < 0.05), but not with medication use, iritis, or smoking. BMD of the lumbar spine in AS patients did not correlate linearly with the course of the disease, but BMD of the femoral neck correlated linearly with the course of the disease (P < 0.05). BMD was correlated with multiple SNPs in patients with AS. Lumbar BMD was correlated with rs7025373 and rs7848078. Femoral head BMD was correlated with 3:102157365, 3:102157417, rs1252202, rs1681355, rs3891857, rs7842614, and rs9870734, suggesting that genetic factors play a role in BMD in patients with AS.Conclusions:The proportion of abnormal bone mass in AS patients was higher than that in healthy individuals of the same age. The factors related to BMD in patients with AS are gender, CRP, and blood calcium. The BMD of the femoral neck of AS patients decreases with the course of the disease, but BMD of the lumbar spine is not related to the course of the disease. BMD in AS patients is associated with multiple SNPs.     

Clinical impact of circulating miR-26a,miR-191, and miR-208b in plasma of patients with acute myocardial infarction

Background

Aberrant expression of several types of miRNAs has been reported in acute myocardial infarction (AMI). The objective of our study was to compare miRNA expression in AMI patients and normal healthy people and determine whether miR-26a, miR-191, and miR-208b could be measured in plasma as indicators for AMI.

Methods

Detection of AMI patients and normal persons by using miRNA microarray chip analysis and miR-26a, miR-191, and miR-208b was screened out. Eighty-seven AMI patients and eighty-seven homogeneous healthy individuals were recruited. Total mRNA including miRNA was isolated and miR-26a, miR-191, and miR-208b expression were determined by qRT-PCR. Receiver operating characteristic curve analysis was performed to evaluate the instructive power of miR-26a, miR-191, and miR-208b for AMI. Dual-luciferase reporter assays indicated p21 is a direct target of miR-208b.

Results

miR-26a and miR-191 were low expressed in AMI compared with normal healthy people, but miR-208b was expressed at a high level in AMI. miR-26a showed an area under the curve (AUC) of 0.745, with a sensitivity of 73.6 % and a specificity of 72.4 %.The AUC for miR-191 was 0.669, with a sensitivity of 62.1 % and a specificity of 69.0 %.The AUC for miR-208b was 0.674, with a sensitivity of 59.8 % and a specificity of 73.6 %.

Conclusions

miR-208b was significantly increased in the AMI compared with healthy people, while miR-26a and miR-191 were decreased. miR-26a, miR-191, and miR-208b were potential indices of AMI, and miR-208b was more effective in patients with non-ST-elevation myocardial infarction.     

Panhandle PCR strategy to amplify the upstream unknown sequence of the Prl gene ofpythium guiyangense

Objective： Based on a partialsubtilisin-like protease, Prl genomic sequence ofPythium guiyangense which has been cloned before, Panhandle PCR strategy was used to amplify the upstream flanking sequence adjacent to the known sequence of the Prl gene. Methods： The genomic DNA was firstly digested with BamH I and then treated with calf intestinal alkaline phosphatase（CIAP）. Next, a 5＇ phosphorylated oligonucleotide was ligated to the 5＇ ends of BamH I -digested DNA. After denaturation, intmstrand annealing and polymemse extension, a pan with a handle was formed,and lastly the nested PCR was performed. Results： A 864 bp product was amplified,which was adjacent to the known sequence of Prl gene.The gene has been accessed by GenBank （Accession：JQ975036）. Conclusion： Panhandle PCR is a quick and convenient approach for amplifying and identifying unknown partner genes,which facilitates cloning full-length Prl gene     

DPYD基因表达与胃癌患者5-氟尿嘧啶敏感性及毒副反应的相关性

目的 观察二氢嘧啶脱氢酶基因（DPYD）表达与胃癌患者5-氟尿嘧啶（5-FU）敏感性及毒副反应的相关性。方法 选取2018年1月—2023年1月在广安市人民医院治疗的胃癌患者60例,取新鲜切除的肿瘤非坏死组织。采用免疫组织化学法检测肿瘤组织DPYD表达强度,实时荧光定量聚合酶链反应检测DPYD mRNA表达,体外药敏试验检测胃癌原代细胞对5-FU的敏感性。术后均采用以5-FU为基础的综合化疗方案,化疗结束后统计化疗效果、毒副反应发生率及严重程度。比较不同DPYD表达强度患者5-FU敏感性;采用Pearson法分析DPYD mRNA表达与药敏指数的相关性;比较不同DPYD表达强度患者毒副反应。结果 60例患者的肿瘤组织中,DPYD低表达34例,高表达26例,高表达患者DPYD光密度值高于低表达患者（P <0.05）。DPYD低表达患者化疗总有效率、5-FU敏感率高于高表达患者（P <0.05）。DPYD mRNA表达与化疗效果（r=-0.664）、药敏指数（rs=-0.892）呈负相关（P <0.05）。DPYD低表达患者3、4级上消化道反应、神经毒性、骨髓抑制、皮肤感...     

内置生物套技术治疗早泄的临床研究

目的 探索一种应用脱细胞异体真皮的"内置生物套"技术,降低阴茎的敏感度,观察其对早泄患者的影响。方法 通过确定适应证后,选择20例早泄患者。采用冠状沟切口,于白膜浅面分离腔穴,植入脱细胞异体真皮,埋没导引针牵引缝合固定近端,远端与深筋膜缝合固定。术后持续加压包扎。6周后可开始性生活。结果 所有患者术后恢复顺利,平均随访时间6个月,未发现血肿、感染等并发症。术前平均射精潜伏期0.67min （0.18~1.1min）;术后阴道内射精潜伏期为2.37min （0.82~8.4min,P<0.05）。结论 内置生物套技术通过植入脱细胞异体真皮,在阴茎体的皮肤和海绵体之间形成一道人为的组织屏障。从本项临床研究观察来看,该手术损伤小,术后并发症少,是一项相对安全的外科操作,而且可以显著延长早泄患者的阴道内射精潜伏期时间。     

Safety and effectiveness of bubble continuous positive airway pressure in preterm neonates with respiratory distress

Background

Studies on Bubble Continuous Positive Airway Pressure (B-CPAP) as respiratory support for neonates are few. The aim of our study was to determine the efficacy and safety of B-CPAP in preterm neonates requiring respiratory support.

Methods

A prospective observation study was done on 50 preterm babies requiring respiratory support for mild to moderate respiratory distress. Support was given with short, nasal cannulae. Surfactant was administered when indicated. Monitoring was done clinically, with pulse oximeter, radiologically and with blood gases. Staff members were also asked their views. Follow-up was done for 3 months.

Results

The mean gestational age was 32.46 (+3.23) weeks and mean birth weight 1454.4 (+487.42) g. Respiratory Distress Syndrome was the commonest indication (30/50). The mean maximum pressure was 6.04 cm H₂O and mean maximum FiO₂ was 72.16%. Mean maximum paO₂, paCO₂ and mean minimum paCO₂ were 92.93 mm Hg (+16.97), 52.36 mm Hg (+ 7.78) and 36.46 mm Hg (+ 4.95) respectively. Early initiation resulted in lesser duration of support. Failure rate was 30%. Apnoea, >1 dose surfactant and late initiation had a statistically higher incidence of failure. Main complications were skin abrasions (30%), feed intolerance (26%) and gastric distension (26%). Survival rate was 94%. 68% of staff felt that it was as easy to use and 88% felt it was more reliable than standard CPAP.

Conclusions

Bubble Continuous Positive Airway Pressure is safe, efficacious and easy to use in preterm neonates with mild to moderate respiratory distress.     

Management of gastrointestinal stromal tumours: a single-centre experience

Background  Gastrointestinal stromal tumours (GISTs), although rare, are increasingly recognized, characterized immuno-phenotypically in most cases by a mutation in C-Kit. The advent of imatinib, a tyrosine kinase inhibitor, has presented a novel and effective therapy in advanced disease. The aim of this study was to present the experience and outcomes of a single centre. Methods  Review of prospective GIST database at St James Hospital from 1997 to 2005. Survival data were analysed using Kaplan–Meier methods. Results  A total of 32 patients (19 males/13 females) with a median age of 61 years (10–84) were treated. The stomach (n = 20) was the dominant site. Surgery was the first line of treatment for all these tumours, and in seven cases this was performed laparoscopically. C-Kit was positive in 81% of cases. The median survival was 78 months with a 5-year survival of 71%. Conclusion  GISTs are rare and surgical resection, increasingly with minimally invasive approaches, is associated with high cure rates, particularly in gastric tumours.     

变异链球菌核糖-5-磷酸异构酶A的表达、纯化与鉴定

目的在大肠杆菌中高效表达变异链球菌核糖-5-磷酸异构酶A(ribose 5-phosphate isomerase A,rpiA),并对表达产物进行纯化和鉴定。方法根据GenBank中变异链球菌UA159株基因组rpiA的DNA编码序列,设计PCR引物,扩增变异链球菌核糖-5-磷酸异构酶A的DNA编码序列,将其克隆至pGEX-6p-1载体中,构建重组质粒,将测序正确的重组质粒转化入大肠杆菌BL21(DE3)中,用异丙基-β-D-硫代吡喃半乳糖苷(isopropylβ-D-1-thiogalactopyranoside,IPTG)诱导表达;对培养温度、IPTG用量、诱导时间等条件进行了优化;用亲和层析、离子交换层析纯化目标蛋白;用SDS-PAGE和质谱对目标蛋白进行鉴定。结果变异链球菌核糖-5-磷酸异构酶A在大肠杆菌中高效、可溶性表达,经质谱鉴定及SDS-PAGE分析,表达产物为变异链球菌核糖-5-磷酸异构酶A蛋白。经过纯化,得到纯度高达95%的变异链球菌核糖-5-磷酸异构酶A。结论成功地在大肠杆菌中高效表达了变异链球菌核糖-5-磷酸异构酶A蛋白,并建立了纯化工艺,得到高纯度的重组蛋白,为进一步研究变异链球菌属核糖-5-磷酸异构酶蛋白的生物学活性及功能奠定了基础。     

COMPARATIVE EVALUATION OF NO-SCALPEL VASECTOMY AND STANDARD INCISIONAL VASECTOMY

No-scalpel vasectomy employs a refined method of dissection and delivery of the vas deferens. We compared no-scalpel vasectomy with standard incisional vasectomy in 176 patients over a 33 month period. The haemorrhage rate was 1.08 per cent for no-scalpel vasectomy compared with 11.9 per cent for standard vasectomy (p < 0.005). The infection rate was 3.26 per cent for no-scalpel vasectomy as against 14.28 per cent for standard vasectomy (p < 0.01). There was a 37.5 per cent reduction in operating time and a substantial reduction in pain during and after the procedure when no-scalpel vasectomy was performed and also there was no failure of vasectomy. No-scalpel vasectomy is a satisfactory alternative to standard vasectomy with fewer complications and increased patient acceptability.KEYWORDS: Male sterilization, Vasectomy