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121.
Gregory James Fox Nguyen Viet Nhung Dinh Ngoc Sy Luu Thi Lien Nguyen Kim Cuong Warwick John Britton Guy Barrington Marks 《PloS one》2012,7(11)
Setting
Existing tuberculosis control strategies in Vietnam are based on symptomatic patients attending health services for investigation. This approach has not resulted in substantial reductions in the prevalence of tuberculosis disease, despite the National Tuberculosis Program achieving high treatment completion rates. Alternative approaches are being considered.Objective
To determine the feasibility and yield of contact investigation in households of patients with smear positive pulmonary tuberculosis among household members of tuberculosis patients in Hanoi, Vietnam.Methods
Household contacts of patients with smear positive pulmonary tuberculosis were recruited at four urban and rural District Tuberculosis Units in Hanoi. Clinical and radiological screening was conducted at baseline, six months and 12 months. Sputum microscopy and culture was performed in contacts suspected of having tuberculosis. MIRU-VNTR molecular testing was used to compare the strains of patients and their contacts with disease.Results
Among 545 household contacts of 212 patients, four were diagnosed with tuberculosis at baseline (prevalence 734 cases per 100,000 persons, 95% CI 17–1451) and one was diagnosed with tuberculosis during the subsequent 12 months after initial screening (incidence 180 cases per 100,000 person-years, 95% CI 44–131). Two of these cases were culture positive for M. tuberculosis and both had identical or near-identical MIRU-VNTR strain types.Conclusion
Household contacts of patients with potentially infectious forms of tuberculosis have a high prevalence of disease. Household contact investigation is feasible in Vietnam. Further research is required to investigate its effectiveness. 相似文献122.
Luu Thi Lien Nguyen Thi Le Hang Nobuyuki Kobayashi Hideki Yanai Emiko Toyota Shinsaku Sakurada Pham Huu Thuong Vu Cao Cuong Akiko Nanri Tetsuya Mizoue Ikumi Matsushita Nobuyuki Harada Kazue Higuchi Le Anh Tuan Naoto Keicho 《PloS one》2009,4(8)
Background
Transmission of tuberculosis (TB) to health care workers (HCWs) is a global issue. Although effective infection control measures are expected to reduce nosocomial TB, HCWs'' infection has not been assessed enough in TB high burden countries. We conducted a cross-sectional study to determine the prevalence of TB infection and its risk factors among HCWs in Hanoi, Viet Nam.Methodology/Principal Findings
A total of 300 HCWs including all staff members in a municipal TB referral hospital received an interferon-gamma release assay (IGRA), QuantiFERON-TB Gold In-TubeTM, followed by one- and two-step tuberculin skin test (TST) and a questionnaire-based interview. Agreement between the tests was evaluated by kappa statistics. Risk factors for TB infection were analyzed using a logistic regression model. Among the participants aged from 20 to 58 years (median = 40), prevalence of TB infection estimated by IGRA, one- and two-step TST was 47.3%, 61.1% and 66.3% respectively. Although the levels of overall agreement between IGRA and TST were moderate, the degree of agreement was low in the group with BCG history (kappa = 0.29). Working in TB hospital was associated with twofold increase in odds of TB infection estimated by IGRA. Increased age, low educational level and the high body mass index also demonstrated high odds ratios of IGRA positivity.Conclusions/Significance
Prevalence of TB infection estimated by either IGRA or TST is high among HCWs in the hospital environment for TB care in Viet Nam and an infection control program should be reinforced. In communities with heterogeneous history of BCG vaccination, IGRA seems to estimate TB infection more accurately than any other criteria using TST. 相似文献123.
Tung Hoang Thanh Thuong Tran Thi Cuong Do Manh Luan Vu Quoc Hien Vu Thi Hieu Tran Nam Nguyen Ba Phuong Hoang Thi Nhu Van The Vinh Bui Khai Hoang Dac Nhut Duong Tan 《Plant Cell, Tissue and Organ Culture》2021,145(2):393-403
Plant Cell, Tissue and Organ Culture (PCTOC) - One of the common problems in strawberry (Fragaria?×?ananassa) micropropagation is the vitrification phenomenon (succulent plantlets,... 相似文献
124.
125.
N. T. Nhung N. V. Cuong J. Campbell N. T. Hoa J. E. Bryant V. N. T. Truc B. T. Kiet T. Jombart N. V. Trung V. B. Hien G. Thwaites S. Baker J. Carrique-Mas 《Applied and environmental microbiology》2015,81(3):812-820
In Mekong Delta farms (Vietnam), antimicrobials are extensively used, but limited data are available on levels of antimicrobial resistance (AMR) among Escherichia coli isolates. We performed a structured survey of AMR in E. coli isolates (n = 434) from 90 pig, chicken, and duck farms. The results were compared with AMR among E. coli isolates (n = 234) from 66 small wild animals (rats and shrews) trapped on farms and in forests and rice fields. The isolates were susceptibility tested against eight antimicrobials. E. coli isolates from farmed animals were resistant to a median of 4 (interquartile range [IQR], 3 to 6) antimicrobials versus 1 (IQR, 1 to 2) among wild mammal isolates (P < 0.001). The prevalences of AMR among farmed species isolates (versus wild animals) were as follows: tetracycline, 84.7% (versus 25.6%); ampicillin, 78.9% (versus 85.9%); trimethoprim-sulfamethoxazole, 52.1% (versus 18.8%); chloramphenicol, 39.9% (versus 22.5%); amoxicillin-clavulanic acid, 36.6% (versus 34.5%); and ciprofloxacin, 24.9% (versus 7.3%). The prevalence of multidrug resistance (MDR) (resistance against three or more antimicrobial classes) among pig isolates was 86.7% compared to 66.9 to 72.7% among poultry isolates. After adjusting for host species, MDR was ∼8 times greater among isolates from wild mammals trapped on farms than among those trapped in forests/rice fields (P < 0.001). Isolates were assigned to unique profiles representing their combinations of susceptibility results. Multivariable analysis of variance indicated that AMR profiles from wild mammals trapped on farms and those from domestic animals were more alike (R2 range, 0.14 to 0.30) than E. coli isolates from domestic animals and mammals trapped in the wild (R2 range, 0.25 to 0.45). The results strongly suggest that AMR on farms is a key driver of environmental AMR in the Mekong Delta. 相似文献
126.
Hoang VD Tan GT Zhang HJ Tamez PA Hung NV Cuong NM Soejarto DD Fong HH Pezzuto JM 《Phytochemistry》2002,59(3):325-329
The eudesmane sesquiterpenoid, verticillatol (1), as well as the lignan, (+)-5'-demethoxyepiexcelsin (2), and a known lignan, (+)-epiexcelsin (3), were isolated from Litsea verticillata Hance. Lignan 2 showed moderate anti-HIV activity with an IC(50) value of 16.4 microg/ml (42.7 microM), while the known lignan 3 was inactive up to a concentration of 20 microg/ml (48.3 microM). Compound 1 demonstrated weak activity with an IC(50) value of 34.5 microg/ml (144.7 microM) while being devoid of cytotoxicity at 20 microg/ml. The structures were elucidated by 1D and 2D NMR spectroscopy, and the absolute configuration of the new sesquiterpenoid was determined by the generation of Mosher esters. 相似文献
127.
New taxa and taxonomic notes in Aspidistra (Convallariaceae s.s.) in China,Laos and Vietnam 下载免费PDF全文
128.
Jörg Schubert Thomas Thieme Ramona Thieme Cuong Viet Ha Giang Thi Hoang 《Journal of Phytopathology》2015,163(7-8):620-631
Eight isolates from different potato growing regions in Vietnam were characterized. All were highly pathogenic in some potato cultivars, but did not overcome the extreme resistance of Solanum stoloniferum and Solanum demissum. RT‐PCR analysis revealed that all of these isolates are recombinants. Sequence data for 4 isolates were obtained, and their reaction in potato cultivars harbouring specific N genes was determined. Different phylogenetic analyses of viral sequences confirmed previous results that the recombinant isolates evolved from different parental sequences. One of the Vietnamese isolates investigated had a specific structure. The need for a clear classification of PVYNWi isolates is discussed. 相似文献
129.
Khai Hoang Dac Mai Nguyen Thi Nhu Tung Hoang Thanh Luan Vu Quoc Cuong Do Manh Ngan Ha Thi My Chau Nguyen Hoai Buu Ngo Quoc Vinh Nguyen Quang Dung Doan Manh Nhut Duong Tan 《Plant Cell, Tissue and Organ Culture》2022,150(1):113-128
Plant Cell, Tissue and Organ Culture (PCTOC) - The acclimatization stress is responsible for high mortality in tissue cultured plants, which significantly reduces micropropagation efficiency. In... 相似文献
130.
Cuong Q. Tang Ulrike Obertegger Diego Fontaneto Timothy G. Barraclough 《Evolution; international journal of organic evolution》2014,68(10):2901-2916
Why organisms diversify into discrete species instead of showing a continuum of genotypic and phenotypic forms is an important yet rarely studied question in speciation biology. Does species discreteness come from adaptation to fill discrete niches or from interspecific gaps generated by reproductive isolation? We investigate the importance of reproductive isolation by comparing genetic discreteness, in terms of intra‐ and interspecific variation, between facultatively sexual monogonont rotifers and obligately asexual bdelloid rotifers. We calculated the age (phylogenetic distance) and average pairwise genetic distance (raw distance) within and among evolutionarily significant units of diversity in six bdelloid clades and seven monogonont clades sampled for 4211 individuals in total. We find that monogonont species are more discrete than bdelloid species with respect to divergence between species but exhibit similar levels of intraspecific variation (species cohesiveness). This pattern arises because bdelloids have diversified into discrete genetic clusters at a faster net rate than monogononts. Although sampling biases or differences in ecology that are independent of sexuality might also affect these patterns, the results are consistent with the hypothesis that bdelloids diversified at a faster rate into less discrete species because their diversification does not depend on the evolution of reproductive isolation. 相似文献