Tropical Medicine and Health
Online ISSN : 1349-4147
Print ISSN : 1348-8945
ISSN-L : 1348-8945
39 巻, 1 号
選択された号の論文の4件中1~4を表示しています
Picture in Tropical Medicine and Health
Original article
  • Duc Tuan Dinh, Mai Thi Quynh Le, Cuong Duc Vuong, Futoshi Hasebe, Koui ...
    2011 年 39 巻 1 号 p. 3-7
    発行日: 2011年
    公開日: 2011/03/24
    [早期公開] 公開日: 2011/02/03
    ジャーナル フリー
    We designed a new set of primers for reverse transcriptase loop-mediated isothermal amplification (RT-LAMP) to specifically amplify the HA gene of avian influenza viruses subtype H5N1. By testing nine H5N1 virus strains and 41 clinical samples collected in Northern Vietnam, we found that the new primers showed higher sensitivity and specificity than the previously published RT-LAMP primers and were comparable to the RT-PCR method currently recommended by WHO. These results suggest that our RT-LAMP assay may be a better choice as a diagnostic tool for current H5N1 influenza virus infection.
  • Chai Fung Pui, Woan Chwen Wong, Lay Ching Chai, Hai Yen Lee, Ahmad Noo ...
    2011 年 39 巻 1 号 p. 9-15
    発行日: 2011年
    公開日: 2011/03/24
    [早期公開] 公開日: 2011/02/26
    ジャーナル フリー
    Salmonellosis outbreaks involving typhoid fever and human gastroenteritis are important diseases in tropical countries where hygienic conditions are often not maintained. A rapid and sensitive method to detect Salmonella spp., Salmonella Typhi and Salmonella Typhimurium is needed to improve control and surveillance of typhoid fever and Salmonella gastroenteritis. Our objective was the concurrent detection and differentiation of these food-borne pathogens using a multiplex PCR. We therefore designed and optimized a multiplex PCR using three specific PCR primer pairs for the simultaneous detection of these pathogens. The concentration of each of the primer pairs, magnesium chloride concentration, and primer annealing temperature were optimized before verification of the specificity of the primer pairs. The target genes produced amplicons at 429 bp, 300 bp and 620 bp which were shown to be 100% specific to each target bacterium, Salmonella spp., Salmonella Typhi and Salmonella Typhimurium, respectively.
Review
  • Eisaku Kimura
    2011 年 39 巻 1 号 p. 17-30
    発行日: 2011年
    公開日: 2011/03/24
    [早期公開] 公開日: 2011/01/14
    ジャーナル フリー
    Diethylcarbamazine (DEC), first introduced in 1947, was shown to have strong efficacy and safety for treatment of human lymphatic filariasis, which is caused mostly by a species Wuchereria bancrofti. Many studies to optimize the dosage and treatment schedule of DEC followed, and, based on the results, control programs with various regimens were implemented in different endemic areas⁄countries. By the mid 1970s, with endorsement by the WHO Expert Committee on Filariasis (3rd report, 1974), the standard DEC regimen for W. bancrofti infection in mass treatment had been established in principle: a total dose of 72 mg⁄kg of body weight given in 12 divided doses, once weekly or monthly, at 6 mg⁄kg each. Not long after the committee report, the efficacy of annual single-dose treatment at 6 mg⁄kg, which is only one twelfth of the WHO-recommended dose in a year, was reported effective in French Polynesia (study period: 1973-78), and later in Samoa (study period: 1979-81). These results were published between 1978 and 1985 in the Bulletin of WHO but received little attention. In the mid 1980s, the efficacy of ivermectin, the first-choice drug for onchocerciasis, against lymphatic filariae came to light. Since the effect at a single dose was remarkable, and often better than DEC, it was predicted that the newly introduced drug would replace DEC. Treatment experiments with ivermectin increased quickly in number. Meanwhile, annual single-dose mass drug administration (MDA) with DEC at 6 mg⁄kg was under scrutiny in Samoa and Fiji. In the early 1990s, the Samoan study, which covered the entire population of 160,000 with 3 annual MDAs, reported a significant reduction in microfilaria (mf) prevalence and mean mf density, while in Fiji, the efficacy of 5 rounds of annual MDA (total dose, 30 mg⁄kg) was shown to be as effective as 28 multi-dose MDA spread over 2 years (6 weekly plus 22 monthly treatments at 5 mg⁄kg; total dose, 140 mg⁄kg). Several additional studies carried out in Samoa in relation to the annual single-dose MDAs revealed that low density mf carriers, who have a very low mf count of 1-20⁄ml of venous blood, could not play a significant role in filariasis transmission.
    From around 1990, studies on spaced low-dose DEC treatments and various types of combination chemotherapy with DEC and ivermectin increased. Albendazole, a well-known anti-intestinal helminths agent, was later added to the combination. The main findings of these studies with W. bancrofti are: (i) a single dose of DEC at 6 mg⁄kg reduced mean mf density by ca. 90% 1 year after treatment; (ii) the same dose could damage⁄kill adult worms; (iii) a single dose of ivermectin at ca. 400 μg⁄kg was more effective than DEC in reducing mf density during the first year and was similarly or less effective in the second year; (iv) ivermectin probably could not kill adult worms; (v) a single combined dose of albendazole (400 mg) and DEC (6 mg⁄kg) was effective to reduce mf density by 85 to nearly 100% 12-24 months after treatment; and (vi) ivermectin or albendazole included in the combination chemotherapy produced “beyond-filariasis” benefits: clearance⁄reduction of intestinal helminths, and, additionally, in the case of ivermectin, skin-dwelling ectoparasites.
    The Global Programme to Eliminate Lymphatic Filariasis (GPELF) started its worldwide activities in 2000, with the target of elimination by 2020. The basic strategy is to conduct annual single-dose MDAs for 4-6 years. In 2000-2007, a minimum of 570 million individuals were treated in 48 of 83 endemic countries. The drugs used are DEC 6 mg⁄kg plus albendazole 400 mg in most countries, or ivermectin 200-400 μg⁄kg plus albendazole 400 mg particularly in onchocerciasis endemic countries in Africa. (MDAs with DEC alone had been used in India.)
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