1.EVALUATION OF AN OGAWA MYCOBACTERIUM CULTURE METHOD MODIFIED FOR HIGHER SENSITIVITY EMPLOYING CONCENTRATED SAMPLES
DAVID LUBASI ; CHARITY HABEENZU ; SATOSHI MITARAI
Tropical Medicine and Health 2004;32(1):1-4
Two egg-based culture media were evaluated for detection of mycobacteria with Löwenstein-Jensen (L-J) as a gold standard. The conventional culture method was modified to improve laboratory diagnosis of tuberculosis in resource scarce countries by employing an inexpensive but sensitive and specific culture method. Sputum samples were collected from pulmonary tuberculosis suspects who visited the chest clinic at the University Teaching Hospital in Zambia. These samples were processed using three different sample treating procedures (with or without sample concentration) and cultured on L-J and Ogawa media for mycobacteria isolation. A total of 276 sputum samples were collected from 138 pulmonary tuberculosis suspects. When the L-J result was used as a standard, the sensitivity of Ogawa and modified Ogawa was 81.7% and 90.3% respectively. Similarly, the specificities of those methods were 96.7% and 92.3% respectively. In total, 90 samples (32.6%) were smear positive and 108 (39.1%) were culture positive. The positivity of each culture method was as follows: 93 (33.7%) in L-J, 98 (35.5%) in modified Ogawa, and 82 (29.7%) in original Ogawa. The contamination rate was 1.1%, 5.1%, and 9.8% for L-J, Ogawa and modified Ogawa respectively. The Ogawa culturing method is economical, simple and quick. Its low sensitivity was overcome by employing the concentration method, the sensitivity significantly improving from 81.7% to 90.3%. Ogawa techniques are ideal in overburdened TB laboratories with poor resources in developing countries.
2.MYCOBACTERIUM TUBERCULOSIS AND gyrA VARIATION IN ZAMBIA
SATOSHI MITARAI ; LYNDON M KAFWABULULA ; CHARITY HABEENZU ; HIROSHI TERUNUMA ; DAVID LUBASI ; FRANCIS C KASOLO ; HARUMI SHISHIDO ; YOSHIO NUMAZAKI
Tropical Medicine and Health 2005;33(2):91-94
M. tuberculosis strains were isolated from clinically and bacteriologically confirmed patients to evaluate the susceptibility of clinical M. tuberculosis isolates to fluoroquinolone and to obtain molecular epidemiological information in Zambia,. The pathogens were subjected to susceptibility testing with isoniazid, rifampicin, ethambutol and streptomycin. The minimum inhibitory concentrations to ciprofloxacin, sparfloxacin and levofloxacin were also evaluated. The gyrA, fluoroquinolone resistance-determining region (QRDR), was sequenced and analysed. As a result, three of the 16 strains examined were resistant to isoniazid, rifampicin and⁄or streptomycin. All of the strains were susceptible to ciprofloxacin, levofloxacin and sparfloxacin. However, a unique gyrA gene variation of M. tuberculosis was identified in the isolates. One strain had a mutation (T73A) in QRDR. Additionally, 81.25% (13⁄16) of the strains tested had Thr at codon 88. Several variations of gyrA gene have been reported in relation to drug resistance. The gyrA variation data will be useful as epidemiological information. It may be important to monitor fluoroquinolone susceptibility even in developing countries for use against resistant M. tuberculosis infection, even though no fluoroquinolone resistance was observed in this study.
3.Worldwide Research Trends on Artesunate:A Bibliometric Analysis From 2001 To 2022
Jialin WANG ; Lubasi David NALISA ; Ying LI ; Hongwei JIANG
World Science and Technology-Modernization of Traditional Chinese Medicine 2024;26(5):1377-1392
Objective This study aims to identify hotspots in this field and predict future research directions by understanding the development trends and hotspots.Methods we analyzed 4102 papers on artesunate from 2001 to 2022 by using two visualization software,CiteSpace and VOSviewer.Results Our findings indicate that the number of artesunate-related articles published has steadily increased in recent years.The United Kingdom participated in the largest number of studies.Mahidron University is the institution with the largest number of publications.Malaria artemisinin,efficacy and cancer are research hotspots in the field of artesunate.Severe malaria,drug resistance,apoptosis and ferroptosis may be the focus of future artesunate-related research.Conclusion Artesunate research focuses on malaria and artemisinin.As a result of bibliometric analysis,new ideas are provided to improve the clinical application of artesunate.