Tamoxifen Induces Apoptosis of Leishmania major Promastigotes in Vitro

Tamoxifen is an antagonist of the estrogen receptor and currently used for the treatment of breast cancer. The current treatment of cutaneous leishmaniasis with pentavalent antimony compounds is not satisfactory. Therefore, in this study, due to its antileishmanial activity, effects of tamoxifen on the growth of promastigotes and amastigotes of Leishmania major Iranian strain were evaluated in vitro. Promastigotes and amastigotes were treated with different concentrations (1, 5, 10, 20, and 50 µg/ml) and time periods (24, 48, and 72 hr) of tamoxifen. After tamoxifen treatment, MTT assay (3-[4,5-dimethylthiazol-2-yl]-2,5 biphenyl tetrazolium bromide assay) was used to determine the percentage of live parasites and Graph Pad Prism software to calculate IC50. Flow cytometry was applied to investigate the induction of tamoxifen-induced apoptosis in promastigotes. The half maximal inhibitory concentration (IC50) of tamoxifen on promastigotes was 2.6 µg/ml after 24 hr treatment. Flow cytometry analysis showed that tamoxifen induced early and late apoptosis in Leishmania promastigotes. While after 48 hr in control group the apoptosis was 2.0%, the 50 µg/L concentration of tamoxifen increased it to 59.7%. Based on the in vitro antileishmanial effect, tamoxifen might be used for leishmaniasis treatment; however, further researches on in vivo effects of tamoxifen in animal models are needed.

[Prevalence and associated factors of head lice infestation among primary schoolchildren in city of Aran and Bidgol [Esfahan Province, Iran], 2008]

Pediculus capitis is a blood sucking insect and an external human parasite that has worldwide distribution. Infection by this parasite has been observed in all age groups, but it is more prevalent among elementary school students. Louse infection causes serious health as well as social problems and stigma. These problems may lead to drop in academic achievement of students. Since no systematic study has been conducted in the city of Aran and Bidgol, this study was carried to examine the frequency rate of infection and factors associated with this disease in elementary students in education year in 2007-2008. In descriptive epidemiologic research, head louse infection was examined in all groups of schools children male and female student in the city of Aran and Bidgol. The students were screened by standard questionnaire and demographic data and related information were obtained by interview and observation. The diagnose of head lice infestation was based on live louse, nymph or nit on the scalp of students. The data were analyzed by SPSS using Chi-square and fisher's exact tests. In this study, a total of 3589 students were examined in 19 male and female schools. The mean age of students was 8.67 +/- 1.57 year and age group ranged between 6-12 year. The prevalence of head louse infestation in students was 0.47%. The head louse frequency were 0.42% and 0.05% in female and male respectively. The head louse infection rate in male and female schools was 0.1% and 1%, respectively. This survey showed that 1% of the female student schools and 0.1% of the male student schools were infected to head louse. The results showed a significant association between pediculosis and sex, father's job, mother's education, bathroom in home, prior infection, drug use and nationality, respectively. The results of study indicated that the prevalence of pediculosis wasn't a major health priority and health concern in the city of Aran and Bidgol in education year 2007-2008. However, it was suggested that enhancing general knowledge about the infection can prevent the increase of infestation incidence. Hygienic teachers and individual hygiene instruction to students play an important role