Biomedical subjects

Qing-wu Jiang

Publications and source records attributed to Qing-wu Jiang.

At least 19 recordsLinked to original sources

PubMed2006

[National surveillance of schistosomiasis in China from 2000 to 2004].

OBJECTIVE: To specify the trends of endemic situation among twenty one national surveillance sites for schistosomiasis from 2000 to 2004. METHODS: According to the national surveillance protocol, longitudinal surveillance on endemic situation of schistosomiasis was carried out at twenty-one sites since 2000. RESULTS: The infection rate of Schistosoma japonicum declined in six of the twenty-one surveillance sites. The density of living snails and of infected snails decreased in two sites but not well controlled in most other sites. The prevalence in cattle fluctuated yearly in most sites and maintained at a relatively high level. During the surveillance period, acute cases were found annually and the number of advanced patients did not increase significantly. No new case and infected snails were found in Jinshan, Shanghai, since 2000, where transmission of schistosomiasis was interrupted two decades ago. CONCLUSION: Routine control strategies such as selective chemotherapy combined with livestock chemotherapy, snail control in risk areas have a positive impact on the control of schistosomiasis. However, these strategies should be lasted for longer time and the surveillance on snails and cattle should be continued.

Adolescent↗

PubMed2006

[Analysis of genetic diversity of AFLP marker among populations of Oncomelania hupensis].

OBJECTIVE: To explore the degree of genetic diversity among populations of Oncomelania hupensis. METHODS: AFLP method was used to amplify the genomic DNA of thirteen snail populations from nine provinces (i. e. Yunnan, Sichuan, Guangxi, Fujian, Hunan, Hubei, Jiangxi, Anhui and Jiangsu) and the genetic diversities among snail populations were analyzed. RESULTS: The number of AFLP fragments amplified ranged from 403 to 472 for thirteen Oncomelania populations. Among the thirteen snail populations, the genetic diversity within the population from Xingzi County, Jiangxi Province, was most significant, and the percentage of polymorphic loci, Nei's genetic diversity and Shannon's information index were 93.22%, 0.345 and 0.510 respectively, while these indices for the snail population from Yizhou City, Guangxi Region, were the lowest, 55.80%, 0.191 and 0.287 respectively. The similarity between the in-group-individuals from Yizhou City, Guangxi Region, was most significant, and the average coefficient of similarity was 0. 904, and that from Dantu County, Jiangsu Province, was the lowest (0.748). The genetic diversities among snail populations were significantly different for the thirteen snail populations (P < 0.01). CONCLUSION: There is a certain genetic variation among Oncomelania snail populations from the mainland of China, and this variation is significantly different among snail populations from different areas.

Amplified Fragment Length Polymorphism Analysis↗

PubMed2006

[Study on the growth of Vibrio cholerae O139 within Acanthamoeba polyphaga and its survival in the cysts in low temperature].

OBJECTIVE: To determine whether Acanthamoeba polyphaga could affect the survival and growth of Vibrio cholerae O139 in low temperature. METHODS: V. cholerae O139 was co-cultured with the Acanthamoeba polyphaga to be examined on its intracellular growth and survival rate within cysts at low temperature, using methods as Gram-staining, electron microscope and passage culture. RESULTS: V. cholerae O139 were observed to enter into the trophozoites and grow the within the vacuoles after 8 hour incubation with Acanthamoeba polyphaga. The germs survived in the vacuole and/or endo-layer of wall and could be re-isolated from the excystment of Acanthamoeba polyphaga. At 30 degrees C, V. cholerae O139 could survive for 120 days with the amoeba while less than 45 days in PAS. At 4 degrees C, the number of viable bacteria decreased and reached undetectable levels for both study and control groups after a 30-day incubation. V. cholerae O139 could be re-isolated from the 30-, 45-, 60- and 75-day's infected cysts after excystment. However the ability of excystment for 90-day's infected cysts decreased and V. cholerae O139 within the cyst could not be isolated again because the amoebae had lysed. CONCLUSION: These findings indicated that V. cholerae O139 could grow within Acanthamoeba polyphaga and the survival time could be increased in the cysts at low temperature. It seemed that Acanthamoeba can provide an environmental reservoir for V. cholerae O139.

Acanthamoeba↗

PubMed2006

[Study on blood biochemical variables of obese children screened by new BMI and weight-for-height criterion].

OBJECTIVE: To evaluate the abnormal state of liver function and plasma lipid levels of obese schoolchildren who were screened by weight-for-height criterion and new body mass index criterion respectively. METHODS: 280 obese children were screened by weight-for-height criterion and 125 obese children were screened by body mass index criterion in a routine school check-up program. All of the latter subjects was included in the former one. One obese child and 1 non-obese child were matched for gender and age. 14 items related to liver functions and plasma lipids were measured. RESULTS: Of the abnormal items,7 items in 125 obese children screened by new BMI criterion and 5 items in 155 "obese children" excluded by BMI criterion, were significantly higher than those children among controlled group. The abnormal rates were 10.4%-22.9% in the former and 3.2%-13.0% in the latter. CONCLUSIONS: The new BMI criterion seemed to be more stringent than weight-for-height. Less than a half of the obese children screened by weight-for-height were taken on obese children by new BMI criterion. The overweight children who were screened by BMI criterion also had abnormal liver functions and plasma lipids.

Body Mass Index↗

PubMed2005

[Linking quantitation of electrophoresis pattern and data analysis in AFLP for Oncomelania hupensis].

OBJECTIVE: To search into a method for analyzing the quantitative data in amplified fragment length polymorphism (AFLP) electrophoresis. METHODS: Oncomelania snails collected from the field were screened. Forty snails found uninfected with schistosomiasis were divided randomly into two groups and used to isolate genomic DNA. AFLP electrophoresis pattern was first transformed into quantitative data by Glyko BandScan software, and the bands were read according to different standards of band-reading to acquire the corresponding data. These data sets were analyzed by genetic statistics to get an inference set, and the analysis of this inference set was performed to reach a summary description. RESULTS: The results of genetic variation from different standards of band-reading were different With the increase of the standard value of band-reading, the indices indicating the genetic polymorphism of Oncomelania hupensis population (e.g. Shannon's information index) also increased. When the standard value reached at certain level, the values of these indices began to decrease. Compared with the above indices, the change for gene flow turned out contrary to the genetic identity. The distributions of inference results from different standards of band-reading all showed significant normal distribution. The mean value of genetic variation based on total grey was very close to that on the proportion of total grey. The average genetic identity between the "subpopulations" was 0.956 according to proportion of total grey or 0.958 from the total grey with an average genetic distance between the "subpopulations" of 0.045 and 0.043 respectively. CONCLUSION: It seems to be a reasonable and accurate method by quantifying the AFLP electrophoresis pattern followed by analyzing the data through the use of the different standards of band-reading.

Animals↗

PubMed2005

[A micro-culture method for continuous observation of free-living amoebae].

OBJECTIVE: To establish a method for co-culture of amoebae and endosymbionts, also for continuously observing the microphenotype of amoebae. METHODS: 24 wells culture plate with cover glass on the wells was used as containers. Amoebae and Candida albicans were co-cultured in microdrop of medium in the wells at 37 degrees C, and observed under x1000. RESULTS: Continuous observation revealed trophozoites in various shapes like letters T, K, or Y, their movement and ingestion phenomenon were observed. CONCLUSION: The micro-culture method is useful in observing the amoebal morphology and its phagocytic process to Candida albicans.

Amoeba↗

PubMed2005

[Gimenez staining: a rapid method for initial identification of legionella pneumophila in Amoeba trophozoite].

OBJECTIVE: To establish a rapid staining method for facilitating initial identification of Legionella pneumophila in amoebal trophozoite. METHODS: Acanthamoeba polyphaga and Legionella pneumophila were co-cultured under laboratory condition. At consecutive time points during the culture, smears of the cultured products were made on glass slides for staining purposes. Different types of stainings including Gram's staining, Gimenez staining, Giemsa staining and immunofluorescence were used to determine the best method for the identification of amoebal pathogens. RESULTS: Gimenez staining technique is simpler and yields better results as compared with the other three stainings. Gimenez stain gives the best color and contrast for amoeba and amoebal Legionella Amoeba trophozoites and/or cysts showed a distinct purplish blue with amoebal Legionella in red. Amoebal Legionella can be distinguished clearly at an earlier time of co cul ture, providing a proper sensitivity. It takes only 10 minutes to finish the operation. The other techniques require the use of expensive reagents, are relatively time-consuming, and involve complex staining procedures. CONCLUSION: Gimenez staining is of value for the initial identification of amoebal pathogens, and it is suitable for laboratory diagnosis.

Amoeba↗

PubMed2005

[Correspondence analysis on random amplified polymorphic DNA genotyping and drug-resistance of Neisseria gonorrhoeae strains in Pudong area, Shanghai].

OBJECTIVE: Using molecular epidemiology methods to investigate relationship between genotypes and drug-resistance of neisseria (N.) gonorrhoeae in Shanghai area. METHODS: A random amplified polymorphic DNA (RAPD) fingerprint method at the molecular level was used to differentiate the strains which were isolated from the outpatients of sexually transmitted disease clinics. The sensitivity to antibiotic of the 78 N. gonorrhoeae strains on 9 different antibiotics was tested and the relationship between different genotypes and phenotypes was studied. RESULTS: Selected RAPD primer could give out a group of amplification polymerase chain reaction bands with some main segments common to all the N. gonorrhoeae strains tested and some segments were different among the N. gonorrhoeae strains. All the 78 N. gonorrhoeae strains could be classified as three different groups (I, II and III). The strains could also be distinguished as four types (A, B, C and D) according to drug-resistance status. Using correspondence analysis method, the relationship between the three genotypes and four resistance types could be identified. CONCLUSION: RAPD fingerprint seemed a useful genotyping method and could be used for molecular epidemiological studies.

Adolescent↗

PubMed2005

[Study on bias and confounding in 'Spatial Epidemiology'].

OBJECTIVE: To explore the biases and confoundings in Spatial Epidemiological studies. METHODS: Possible bias and confounding and their impact on study results in Spatial Epidemiology were analyzed in given examples. RESULTS: In Spatial Epidemiology, biases related to ascertainment/numerator/denominator induced by the choice of the disease induction/latency period and mis-specification of exposure-disease model, exposure inaccuracy, spatial dependency, significance tests etc. were involved, as well as to ecological, socio-economic confoundings factors. CONCLUSION: The sources of bias in 'Spatial Epidemiology' were both numerous and complex, that might be overestimated or underestimated on the study results. Hence, careful interpretation of such studies was needed.

Bias↗

PubMed2005

[To develop a model on severe acute respiratory syndrome epidemics to quantitatively evaluate the effectiveness of intervention measures].

OBJECTIVE: To build an epidemic model of severe acute respiratory syndrome (SARS) to be used to quantitatively evaluate the effectiveness of intervention measures. METHODS: Following the nature of SARS epidemics, an epidemic model of SARS based on SEIR model of infectious disease was built, in which case management group was set up and some parameters related to control measures were included. As an example, data gathered from Beijing was fitted to illustrate its application to quantitatively evaluate the intervention measures. RESULTS: In the newly developed model of epidemics, parameters related to control measures could easily be modified. When scenario assumption was used, a model on SARS outbreak under various circumstances of intervention measures could be set. Thus, quantitative evaluation of intervention measures could perfectly be caried out. Pilot study revealed that the fitness existed in modeling the outbreak of SARS in Beijing and the intervention measures implemented around April 20, 2003, had major contribution to the control of SARS. CONCLUSION: The model of SARS epidemics seemed to be stable and reliable to be used to evaluate the effectiveness of intervention measures implemented during the SARS outbreak in a quantitative way.

China↗

PubMed2005

[Survival and growth of Vibrio cholerae O139 inside Acanthamoeba].

OBJECTIVE: To study the survival and growth of Vibrio cholerae inside the Acanthamoeba polyphage. METHODS: Survival and growth of Vibro cholerae O139, co-cultured with Acanthamoeba polyphaga, was observed inside the trophozoites and cysts, using Gram stain and electron microscope. RESULTS: Viable O139 was observed inside the amoebal vacuoles in 24 hours. Vacuoles were filled with more bacteria along with the longer period of co-culture. The process of O139 infection with Amoebae would include uptake, formation of O139 vacuole, multiplication, trophozoites lysed and expel under electron microscopy. Some infected trophozoites could subsequently encyst and the surviving O139 could locate in the vesicles inside the cysts. CONCLUSION: O139 might survive and multiply in the trophozoites and reside inside the cysts of Amoebae, suggesting that Acanthamoebae might serve as one of the environmental hosts of Vibro cholerae.

Acanthamoeba↗

PubMed2005

[Sequence analysis of Echovirus type 30 isolated from an aseptic meningitis outbreak in northern Jiangsu province in 2003].

OBJECTIVE: To determine the partial sequence of virus strains causing an aseptic meningitis outbreak in northern part of Jiangsu province in 2003 and to compare them with the same serotype strains isolated in other countries to better understand its genetic characteristics and hereditary trend of development. METHODS: Virus RNA was amplified using two sets of specific enteroviral 3' half of VP1 primers 012/011 and 040/011. Polymerase chain reaction (PCR) products were purified and sequenced. BLAST program was then used to perform on nucleotide and amino acid pairwise-alignment with all available sequences in NCBI database. Phylogenetic trees were drawed to compare with other enteroviral sequences using PHYLIP software. RESULTS: Under BLAST program, three sequences we submitted to GenBank were identically inferred as echovirus type 30, which had been identified by neutralization test in previous study. Phylogenetic analysis demonstrated that strains isolated from this outbreak were aggregated into a cluster, and the closest relationships with them were those isolated in 1999 and 2000. This phenomenon indicated that Echo30 from this outbreak was different from other strains in different epidemic area. CONCLUSION: 3' half of VP1 sequence could be used to quickly identify the serotype of isolated enterovirus. Strains isolated from this outbreak had the similar hereditary developing trend comparing with Echo30 strains isolated from other countries.

Base Sequence↗

PubMed2005

[A Monte-Carlo study for propensity score methods].

OBJECTIVE: To evaluate the statistical property of the estimators on exposure effect and value of propensity score methods in practical use. METHODS: Simulation data, propensity score methods (PSM) were conducted to assess bias and efficiency, under both with/without model misspecification conditions. RESULTS: Under model misspecification conditions, propensity score methods had better robustness than model based methods. CONCLUSION: For large and complicated data, propensity score methods had more flexibility in practical use than model based methods.

Algorithms↗

PubMed2005

[Phylogenetic analysis for H3A1 strain of all human influenza A virus].

OBJECTIVE: Influenza A virus remains an important pathogen which threatens humans. With the help of latest developed bioinformatics tools, all available human Influenza A virus H3A1 strains were explored to deeply understanding its evolution and variation rules. METHODS: All data of H3A1 sequence in NCBI Genbank and Influenza sequence database were downloaded and aligned in ClustalX with two step cluster method used to split the data and Bayesian phylogenetic tree analysis method applied to precisely construct phylogenetic tree for each clusters. RESULTS: Tree topology indicated that H3 strains evolved along a single evolution trunk and tree pattern and model parameter showed obvious variety tendency with time period. However, no geographic distribution features were found for key variation strains and big branch in trees. CONCLUSION: The evolution of human H3 strains were mainly driven by the interaction of human immune barriers and antigenic drift of virus. Since the influenza subtype had already been spread in human population, south China should not be considered as the originated areas of new strains, hence it should be treated as equally as other places in the world.

Antigens↗

PubMed2005

[Study on the impact of exposure misclassification on the validity of a study].

OBJECTIVE: To explore the impact of misclassification in binary explanatory variables on the effects associated with 'exposure-disease'. METHODS: Based upon the functions of probabilities on misclassification, effects of association and proportions of exposure, the 'R Project for Statistical Computing' method was used to analyze the impact of misclassification on the validity of a study. RESULTS: To the linear model case, the effect of nondifferential misclassification serves as an attenuating bias. When r = 0.5, the bias is symmetric in both sensitivity and specificity but when r is not equal to 0.5, the bias is not symmetric in sensitivity and specificity. When misclassification is nondifferential, estimated odds ratio tends to be 1 while the exposure prevalence in the control tends to be 0 or 1. Bias seems to be very complex in differential misclassification than in nondifferential misclassification that can make OR tend to or be away from the null value. CONCLUSION: The impact of exposure misclassification on the effect associated with exposure--disease is complicated, hence necessary to understand, to control, and to assess bias of misclassification in order to correctly interpret the results of a study.

Bias↗

PubMed2004

[Canonical correlation and redundancy analysis on the indices of abdominal ultrasonography of schistosomiasis japonica].

OBJECTIVE: To explore the correlation of the ultrasound indices of liver and spleen in schistosomiasis japonica and with infection frequency, infection time and EPG. METHODS: The canonical correlation was applied to analyze the correlation of the hepatosplenic ultrasound indices in schistosomiasis japonica, and the correlation of the ultrasound indices with infection frequency, infection time and EPG. The proportions of variation related to each other in liver and spleen were analyzed by the redundancy analysis. RESULTS: The correlation coefficients of the first pair correlation canonical variable were 0.7842, 0.5483 and 0.5800, 0.4220, respectively, in males and females without infection, males and females with infection history (P<0.01). The correlation coefficients of the first pair correlation canonical variable were 0.6063, 0.5215 and 0.6595, 0.3849, respectively, in male negatives and female negatives, male positives and female positives (P<0.01). In groups of males and females without infection, the variations of liver ultrasound indices related with the variation of spleen ultrasound indices were 43.5% and 17.5% respectively, and in groups infection history, they were 22.1% and 11.4% respectively. In male and female negative groups, the variations of liver ultrasound indices related with the variation of spleen ultrasound indices were 26.8% and 16.8% respectively, and in positive groups, they were 27.6% and 10.7% respectively. The infection frequency, infection time and EPG in the stool-positive groups were not significantly related with the canonical variables of liver and spleen ultrasound indices (P>0.05). CONCLUSION: There is a significant canonical correlation between the liver and spleen ultrasound indices in schistosomiasis japonica, especially in males. In groups with infection history, the infection frequency, infection time and EPG of those stool-positives are not relevant to the canonical variables of liver and spleen ultrasound indices.

Adolescent↗

PubMed2004

[Evaluation of the reliability of three different hepatitis E diagnosis reagents on the clinical acute hepatitis E].

OBJECTIVE: To evaluate the reliability of different hepatitis E diagnosis reagent tests on the acute hepatitis E. METHODS: Three acute hepatitis E diagnosis tests, E2-IgM (Wantai, China), GL-IgM and GL-IgG (Genelabs, Singapore) were compared for their reliability in a sera panel composed by 273 healthy individuals and 525 hepatitis. RESULTS: The specificity of E2-IgM on the diagnosis of acute hepatitis E was 100.0%, it was significantly higher than GL-IgM (96.7%) and GL-IgG (85.4%). The sensitivity of E2-IgM and GL-IgG were 97.9% and 93.8% respectively, both significantly higher than GL-IgM (72.9%). Among 65 acute hepatitis cases being positive on GL-IgM test but negative on E2-IgM, 58 (89.2%) cases were found to be positive with anti-hepatitis A virus IgM, it indicated that the GL-IgM test might be interfered by other IgM antibodies on serum. CONCLUSION: E2-IgM is a good test for the diagnosis of acute hepatitis E.

Acute Disease↗

PubMed2004

[Study on the seropositive prevalence of human immunodeficiency virus in a village residents living in rural region of central China].

OBJECTIVE: To study the human immunodeficiency virus (HIV) prevalence of residents living in a village located in rural region of central China where the paid blood donors used to be popular. METHODS: All residents of one village "ZY" were asked to participate in HIV serologic screening test. Those over the age of 16 and participated in HIV serologic test was followed to undergo an indoor interview a week later, to finish a questionnaire, which including information on demography, marital status, smoking and drinking habits, history of blood donation, sexual behavior and history of drug use. Names on those either died from AIDS or having HIV serologic testing before were collected from local hospitals and the Center of Disease Control and Prevention. RESULTS: There were in total 2364 residents in 527 households in "ZY" village including 1551 residents participated in the HIV serologic screening test, and 926 completed questionnaires. A total of 115 HIV seropositive residents were found in the HIV screening. 5 had been undergone HIV screening tests before, and 24 died of AIDS. The HIV prevalence of the whole population was 9.1% (CI: 7.7% - 10.6%). There were 19.6% households had at least one member living with HIV, out of which 25% had over two HIV seropositive members. No significant difference was found between genders with respect to HIV prevalence. 40 - 50 years old group had the highest HIV prevalence, significantly differed from other age groups. The HIV prevalence among former paid blood donors was 22.4%. The proportions of getting HIV infection through routes of blood transfusion, sex and mother-to-child, were 0.9%, 9.6% and 5.2% respectively among 115 HIV seropositive residents. CONCLUSION: Some villages in the rural regions of central China showed high HIV prevalence. Former paid blood donation was responsible for the main transmission route in these villages. However, sexual transmission and mother-to-child transmission were becoming dominant routes in general population which called for effective action be taken to contain the spread of HIV.

Adolescent↗