Antidepressant-like effect of resveratrol in a subchronic model of depression

Depression is one of the most serious and common mental diseases with major negative social consequences. Transresveratrol [trans-3,5,4´-trihydroxystilbene] is a polyphenolic compound with a broad spectrum of pharmacological activities. It has been detected in some fruits and herbs, including the Asian plant Polygonum cuspidatum. The aim of this study was to assess the antidepressant-like effect of transresveratrol in a reserpine subchronic model of depression. Depression-like behaviours were induced in rats by reserpine injection [0.25 mg/kg, subcutaneously] every 48 h, for 20 days. Transresveratrol [60 and 120 mg/kg] and fluoxetine [10 mg/kg] were administered orally daily during the 20 days of the study. Behavioural tests, namely, open-field test and forced swimming test, as well as brain neurotransmitters levels and antioxidant contents and liver functions, were assessed. Data revealed that transresveratrol improved the rats' behaviour in both the open-field test and forced swimming test, and also elevated the brain's neurotransmitter content, normalized the liver enzymes level, and improved the antioxidant status of both the brain and liver, compared with those of fluoxetine. The present study provided a clear evidence for the antidepressant-like of transresveratrol in the experimental model of depression. Further investigations are required to investigate the mechanism of action of transresveratrol as well as its applicability to be used as an antidepressant

Filariasis elimination in Egypt: impact of low microfilaraemics as sources of infection for mosquitoes

The elimination strategy for lymphatic filariasis aims at reducing blood microfilaraemia to levels at which vector transmission cannot be sustained. We aimed to determine whether patients with pre-treatment low or ultra-low microfilaria [MF] counts could be a reservoir of infection after mass drug administration [MDA] with a combined regimen. Laboratory-reared mosquitoes were fed on 30 volunteers after 2 rounds of MDA. Microfilaria uptake, infectivity rates and number of Wuchereria bancrofti L3 per mosquito were assessed. One year after MDA-1, 6 subjects transmitted MF, but up to 9 months after MDA-2 transmission failed. Six months after MDA-2 > 90% had clear MF smears and either failed to transmit MF or transmitted MF that did not develop to L3. We conclude that the transmission cycle is seriously weakened after MDA-2

Uptake and development of wuchereria bancrofti in culex pipiens L and aedes caspiuspallas

Studies were conducted to compare early phenomena associated with W. bancrofti infection and further development in the filaria vector Culex pipiens and the refractory mosquito Aedes caspius. Ingestion rates evaluated immediately after simultaneous feeding on an infected human were 69.1% for 43 Cx. pipiens and 35.7% for 28 Ae. caspius. The observed number of mf ingested by either mosquito did not vary significantly [2.7 +/- 1.4, and 2.3 +/- 0.9, respectively] and, based on the size of the blood meal ingested [2.8 and 2.3 mul, respectively], a 2-fold mf concentration factor was recorded for both species. Blood ingested by Cx. pipiens [N = 16] and Ae. caspius [N = 10] clotted within 120 and 90 minutes post-feeding, respectively. The time difference observed however, did not affect significantly the rates of migration into the hemocele [56 and 67%, respectively]. Comparison of initial infection rates with those obtained after the extrinsic incubation period of the parasite was completed, indicated that the proportion of infected Cx. pipiens was reduced by 3.9% and that of Ae. caspius by 30%. Furthermore, the observed infectivity ratio of 265 Cx. pipiens that had an infective blood meal was 0.74 and only 0.009 for 70 Ae. caspius

Morphological keys for the separation of the rhipicephalus sanguineous group of ticks [acarina: ixodidae] in Egypt

Rhipicephalus sanguineus sensu stricto is the taxonomic baseline for the R. sanguineus group of ticks which consists of 4 species in Egypt. Due to the potential confusion in the differentiation of species within the group, particularly in the Middle East, there is an urgent need for the development of new diagnostic keys. Keys, based on morphological characters, were provided for the various stages of R. sanguineus ticks in Egypt. An additional plan provides a useful tool for distinguishing most field collected specimens