无锡地区2001年-2002年生殖道感染者4种支原体分子流行病学研究

目的 了解无锡地区 2 0 0 1年 - 2 0 0 2年男女性生殖道感染者解脲脲原体 (Uu)、人型支原体 (Mh)、生殖支原体(Mg)、肺炎支原体 (Mpn)感染状况。方法 收集 2 0 0 1年～ 2 0 0 2年来无锡市第一人民医院就诊的 16 0 0例男女性生殖道感染者病灶部拭子标本 (男 :尿道拭子 ,女 :阴道拭子 ) ,应用套叠式聚合酶链反应 (nPCR)技术进行Uu、Mh、Mg和Mpn 4种支原体核酸检测。结果 16 0 0例男女性生殖道感染者Uu、Mh、Mg和Mpn 4种支原体阳性率分别为 4 2 .3%、18.9%、5 .0 %和 6 .1% ,支原体总阳性率达 5 1.5 % ;其中女性Uu、Mh 2种支原体的检出率明显高于男性。结论 无锡地区 2 0 0 1年 - 2 0 0 2年男女性生殖道感染者中支原体感染率高 ,且已构成流行。

绿脓杆菌的分子流行病学研究进展

绿脓杆菌是最常见的医院感染病原菌,其临床流行病学研究发展最迅速的是分子流行病学的研究。本文着重介绍绿脓杆菌的质粒分析,限制性核酸内切酶及核酸分子杂交技术的原理、方法及临床应用,绿脓杆菌复杂的耐药机理及传播规律的研究,为防止其流行提供依据。

Comparison of Multiplex Fluorescent PCR with Serum Type-specific Antibody Detection in Diagnosis of Genital Herpes

Objectives: To compare multiplex fluorescent PCRwith serum type-specific antibody detection in thediagnosis of herpes simplex virus (HSV) infection andto evaluate its significance in the diagnosis of genitalherpes.Methods: We detected HSV infection in 121 speci-mens collected from patients with genital herpesusing both multiplex fluorescent PCR and serum type-specific antibody detection. HSV viral isolation wasused as the standard control.Results: When compared with the viral isolation, thesensitivity and specificity for multiplex fluorescentPCR were 100% and 88.89%, respectively afterdiscrepant analysis. The sensitivity and specificity fortype-specific antibody detection was 77.68 % and77.78 %, respectively. However, the type-specificantibody detected HSV in two asymptomatic patientswhile the multiplex fluorescent PCR couldn’t detectany HSV DNA from those specimens.Conclusions: Multiplex fluorescent PCR is a verysensitive and specific method for detection and typingof HSV in the lesion of genital herpes, it failed todetect HSV DNA from the asymptomatic patients.Serum type-specific antibody detection was a lesssensitive and specific test but could detect the specificantibody from some asymptomatic patients. Thecombination of these two techniques would allow rapid,sensitive and accurate detection and typing of HSVand help clinical diagnosis and epidemiologic survey-ing of genital herpes.

Portal vein thrombosis:Prevalence,patient characteristics and lifetime risk:A population study based on 23796 consecutive autopsies

AIM： TO assess the lifetime cumulative incidence of portal venous thrombosis （PVT） in the general population. METHODS： Between 1970 and 1982, 23 796 autopsies, representing 84% of all in-hospital deaths in the Malmo city population, were performed, using a standardised protocol including examination of the portal vein. PVT patients were characterised and the PVT prevalence at autopsy, an expression of life-time cumulative incidence, assessed in high-risk disease categories and expressed in terms of odds ratios and 95% CI. RESULTS： The population prevalence of PVT was 1.0%. Of the 254 patients with PVT 28% had cirrhosis, 23% primary and 44% secondary hepatobiliary malignancy, 10% major abdominal infectious or inflammatory disease and 3% had a myeloproliferative disorder. Patients with both cirrhosis and hepatic carcinoma had the highest PVT risk, OR 17.1 （95% CI 11.1-26.4）. In 14% no cause was found; only a minority of them had developed portal-hypertension-related complications. CONCLUSION： In this population-based study, PVT was found to be more common than indicated by previous clinical series. The markedly excess risk in cirrhosis and hepatic carcinoma should warrant an increased awareness in these patients for whom prospective studies of directed intervention might be considered.

Nutrition and physical activity in NAFLD:An overview of the epidemiological evidence

Nonalcoholic fatty liver disease(NAFLD)has been recognized as a major health burden.The high prevalence of NAFLD is probably due to the contemporary epidemics of obesity,unhealthy dietary pattern,and sedentary lifestyle.The efficacy and safety profile of pharmacotherapy in the treatment of NAFLD remains uncertain and obesity is strongly associated with hepatic steatosis;therefore,the first line of treatment is lifestyle modification.The usual management of NAFLD includes gradual weight reduction and increased physical activity(PA)leading to an improvement in serum liver enzymes,reduced hepatic fatty infiltration,and,in some cases,a reduced degree of hepatic inflammation and fibrosis.Nutrition has been demonstrated to be associated with NAFLD and Non-alcoholic steatohepatitis(NASH)in both animals and humans,and thus serves as a major route of prevention and treatment.However,most human studies are observational and retrospective,allowing limited inference about causal associations.Large prospective studies and clinical trials are now needed to establish a causal relationship.Based on available data,patients should optimally achieve a 5%-10%weight reduction.Setting realistic goals is essential for long-term successful lifestyle modification and more effort must be devoted to informing NAFLD patients of the health benefits of even a modest weight reduction.Furthermore,all NAFLD patients,whether obese or of normal weight,should be informed that a healthy diet has benefits beyond weight reduction.They should be advised to reduce saturated/trans fat and increase polyunsaturated fat,with special emphasize on omega-3 fatty acids.They should reduce added sugar to its minimum,try to avoid soft drinks containing sugar,including fruit juices that contain a lot of fructose,and increase their fiber intake.For the heavy meat eaters,especially those of red and processed meats,less meat and increased fish intake should be recommended.Minimizing fast food intake will also help maintain a healthy diet.PA should be integrated into behavioral therapy in NAFLD,as even small gains in PA and fitness may have significant health benefits.Potentially therapeutic dietary supplements are vitamin E and vitamin D,but both warrant further research.Unbalanced nutrition is not only strongly associated with NAFLD,but is also a risk factor that a large portion of the population is exposed to.Therefore,it is important to identify dietary patterns that will serve as modifiable risk factors for the prevention of NAFLD and its complications.

INFLUENCE OF MIMIC CARDIAC RATE ON HYDRODYNAMICS OF DIFFERENT MECHANICAL PROSTHETIC CARDIAC VALVES IN VITRO

Objective To assess the influence of mimic cardiac rate on hydrodynamics of different mechanical prosthetic cardiac valves. Methods US-made CarboMedics bileaflet valve, China-made Jiuling bileaflet valve and C-L tilting disc valve were tested via a pulsatile flow simulator in the aortic position. Testing conditions were set at mimic cardiac rates of 55 bpm, 75 bpm, 100 bpm with a constant mimic cardiac output of 4 L/min. The mean pressure differences (ΔP), leakage volumes (LEV) and closing volumes (CLV) across each valve, and effective orifice areas (EOA) were analyzed. Results Within physiological range, ΔP, LEV, and CLV decreased as mimic cardiac rate increased, with a large extent of variance. EOA increased along with an increase in mimic cardiac rate. It was a different response in terms of cardiac rate alteration for different types of mechanical prosthetic cardiac valves. Conclusion Mimic cardiac rate change affects hydrodynamics of mechanical prosthetic cardiac valves. Within physiological range, the hydrodynamic of prosthetic bileaflet valve is better than that of tilting disc valve.

Chlamydia Trachomatis and Ureaplasma Urealyticum Transmission Between Regular Sexual Partners

Objective: To investigate the transmission ratio andepidemiology of Chlamydia trachomatis (Ct) andUreaplasma urealyticum (Uu) between regular sexualpartners. Methods: We collected secretion specimens of geni-tourinary tract from sexual partners who attended ourclinic during the period from May 1, 1999 to May 31,2000 and then detected Ct and Uu in the specimens. Results: The inconsistent rate of Ct and Uu infectedbetween sexual partners was 59.22% and 38.92%respectively. There were no correlations between pa-tients' age and the inconsistent rate of Ct and Uu in-fected (P>0.05). The most common inconsistency be-tween regular partners was seen in man with Ct infec-tion while in female with Uu infection; and in manwith concurrent infection of Ct while in female onlywith Uu; or in man with Ct infection while in female noCt and Uu were detected. Conclusion: The sexual transmitting ability of Ctand Uu is not as active as we have expected.

Epidemiology and clinical course of Crohn's disease:Results from observational studies

The authors review the clinical outcome in patients with Crohn's disease(CD)based on studies describing the natural course of the disease.Population-based studies have demonstrated that the incidence rates and prevalence rates for CD have increased since the mid-1970s.The authors search for English language articles from 1980 until 2011.Geographical variations,incidence,prevalence,smoking habits,sex,mortality and medications are investigated.An increasing incidence and prevalence of CD have been found over the last three decades.The disease seems to be most common in northern Europe and North America,but is probably increasing also in Asia and Africa.Smoking is associated with an increased risk of developing CD.Age <40 at diagnosis,penetrating/stricturing complications,need for systemic steroids,and disease location in terminal ileum are factors associated with higher relapse rates.A slight predominance of women diagnosed with CD has been found.Ileocecal resection is the most commonly performed surgical procedure,and within the first five years after the diagnosis about one third of the patients have had intestinal surgery.Smoking is associated with a worse clinical course and withincreased risk of flare-ups.In most studies the overall mortality is comparable to the background population.To date,the most effective treatment options in acute flares are glucocorticosteroids and tumor necrosis factor(TNF)-α-blockers.Azathioprine/methotrexate and TNF-α-blockers are effective in maintaining remission.

Genetic Variation in Field Populations of Baculoviruses: Mechanisms for Generating Variation and Its Potential Role in Baculovirus Epizootiology

Baculoviridae is a family of insect-specific DNA viruses that have been used as biological control agents for insect pest control. In most cases these baculovirus control agents are natural field isolates that have been selected based on their infectivity and virulence. The advent of molecular tools such as restriction endonucleases, targeted polymerase chain reaction and new DNA sequencing strategies have allowed for efficient detection and characterization of genotypic variants within and among geographic and temporal isolates of baculovirus species. It has become evident that multiple genotypic variants occur even within individual infected larvae. Clonal strains of baculovirus species derived either by in vitro or in vivo approaches have been shown to vary with respect to infectivity and virulence. Many of the cell culture derived plague-purified strains have deletions that interrupt egt expression leading to virus strains that kill infected hosts more quickly. As well, in vitro clones often involve larger genomic deletions with the loss of pif gene function, resulting in strains deficient for oral infectivity. There are an increasing number of baculovirus species for which complete genome sequences are available for more than one strain or field isolate. Results of comparative analysis of these strains indicated that hr regions and bro genes often mark "hot spots" of genetic variability between strains and of potential recombination events. In addition, the degree of nucleotide polymorphisms between and within strains and their role in amino acid substitutions within ORFs and changes in promoter motifs is also beginning to be appreciated. In this short review the potential mechanisms that generate and maintain this genetic diversity within baculovirus populations is discussed, as is the potential role of genetic variation in host-pathogen interactions.

Study on the Biology and Epidemiology of Uncinula necator---The Causal Agent of Grape Powdery Mildew Disease

This study was carried out during 2007-2009 in the vineyards of Ardebil province of lran to study the biology and the epidemiology of Uncinula necator--the causal agent of grape powdery mildew disease. The study concentrated on the survival and the initiation of primary inoculum of the fungal causal agent. Results of histopathological experiments indicated that U. necator survived as mycelium in the dormant buds of the grapes during winter season. Results of study on the effect of environmental factors on fungus biology showed that the pathogenic activity of the fungus began when the temperature was between 16-19 ℃ with a relative humidity more than 50%. It was also found that optimum temperature and relative humidity for the sporulation of U.necator was 20-25 ~C and 50%-100% respectively. According to the results, fungal conidia were trapped during formation of 5-6 true leaves and first disease symptoms were observed on the clusters on late June after fruit formation. Fungal cleistothecia were observed abundantly at the end of season on the leaves, petioles and twigs but they were not able to survive during winter. Formation of ascospores on young leaves was proved but their role as the primary inoculum was not supported by the results of this study. Results of this study and the new findings on the biology and epidemiology of U.necator may be of national and international interests for the management of powdery mildew disease which is one of the most destructive diseases around the world including Iran.

Intrahepatic cholestasis of pregnancy

Intrahepatic cholestasis of pregnancy (ICP) is a pregnancy-specific liver disorder characterized by maternal pruritus in the third trimester, raised serum bile acids and increased rates of adverse fetal outcomes. The etiology of ICP is complex and not fully understood, but it is likely to result from the cholestatic effects of reproductive hormones and their metabolites in genetically susceptible women. Equally unclear are the mechanisms by which the fetal complications occur. This article reviews the epidemiology, clinical features, diagnosis, etiology and management of ICP.

A Molecular Epidemiology Analysis of HIV in Shenzhen and HIV Env Gene Variation Replication Analysis

Objective: To analyze molecular trends of the HIV epidemic in Shenzhen. Methods: Serum collected from Shenzhen AIDS patientsbetween 1992-1999 was analyzed using molecular techniques.DNA fragments of the HIV-1 Env gene were amplified bynested PCR from uncultured peripheral blood mononuclearcells (PBMCs) from these serum samples. The C2-C3 region ofthe Env gene was sequenced and analyzed. Specific high-riskbehaviors were also analyzed. Results: We found that the transmission of HIV in the citywas mainly through sexual behaviors (46.0%). There werefour HIV-1 subtypes: B', B, C and E with 6.31%, 7.95%,3.09% and 8.92% gene divergence inside each subtype inShenzhen. These results suggested that epidemic times were 6,8, 3 and 9 respectively. The main cpidemic subtypes were Eand B strains. AIDS patient's antigenic variation was slightlyhigher than that of HIV infected individuals. Conclusion: Surveillance data reflect trends and theepidemic time of HIV which will be useful for policy makersto formulate effeive strategies of HIV/AIDS prevention and control in Shenzhen.

Effects of continuous intermedin infusion on blood pressure and hemodynamic function in spontaneously hypertensive rats

Objective To examine the effects of exogenously administered intermedin （IMD,adrenomedullin-2） on arterial blood pressure,cardiac function and the cardiovascular IMD receptor system in spontaneously hypertensive rats （SHRs） as well as to investigate the associated mechanisms.Methods Thirteen week-old male rats were divided in Wistar Kyoto （WKY） group （n =12）,SHR group （n =12）,IMD group （SHRs infused with IMD 1-47 500 ng/kg per hour,n =12）,and ADM group （SHRs infused with adrenomedullin 500 ng/kg per hour,n =12）.Results A two-week continuous administration of low dose IMD 1-47 via mini-osmotic pumps markedly reduced blood pressure,the maximal rates of increase and decrease of left-ventricle pressure development （LV ± dp/dtmax）,left ventricular systolic pressure and heart rate in SHRs.Furthermore,IMD also inhibited protein over-expression of cardiovascular IMD receptors,myocardial Receptor Activity-Modifying Proteins （RAMP1 and RAMP2）,aortic RAMP1,RAMP2,RAMP3,and calcitonin receptor-like receptor （CRLR）;suppressed up-regulation of aortic RAMP1,RAMP2,RAMP3 and CRLR gene expression; and markedly elevated the mRNA abundance of myocardial atrial natriuretic peptide （ANP） and myocardial brain natriuretic peptide （BNP）.Additionally,IMD 1-47 administration in SHRs increased aortic cAMP concentration and reduced myocardial cAMP concentration.Conclusion These findings support the speculation that IMD,as a cardiovascular active peptide,is involved in blood pressure reduction and cardiac function amelioration during hypertension.The mechanism underlying this effect may involve IMD binding of a receptor complex formed by RAMPs and CRLR,and consequential regulation of cAMP levels and other cardiovascular active factors,such as ANP and BNP.