Ecological site distribution of sand fly species of Mokolo, an endemic focus of cutaneous leishmaniasis in northern Cameroon

Leishmaniasis is a vector borne disease present in two major clinical forms (cutaneous and visceral) in the northern part of Cameroon. The disease is classified as a neglected tropical disease by the World Health Orga-nization and thus, requires more attention. The aim of this study was to correlate the previously established composition and abundance of sand fly fauna with the putative vector status and the ecological behavior in the Mokolo cutaneous leishmaniasis focus to propose fighting strategies integrating vectors control. Over a 12-month period light traps were used for sand flies' collection in urban, peri-urban and sylvatic environment found in Mokolo, an endemic focus of leishmanisis in northern Cameroon, microscope and taxo-nomic keys were used for their identification. Nineteen (19) species were identified belonging to the genera Sergentomyia, and Phlebotomus. The influence of human population density on sand fly's species density and composition was assessed trough the evaluation of ecological distribution of sand flies in Mokolo. It came out that, Se. coronula and Se. thomsoni mandarai are strictly wild species and Ph. duboscqi, a domestic species. The other species are generalists.The number of Se. antennata and Se. adami decreases with the increase of the density of human population while Se. distincta, Se. vorax and Ph. duboscqi increase with the density of human population in the study site. Based on its previous reports in the Leishmania transmission in West Africa, Ph. duboscqi should still be considered as the main suspected vector in Mokolo. Ph. duboscqi, Se. distincta, Se. affinis ssp. vorax and Se. schwetzi are highly represented around human dwellings

自由:21 各種霊長類こおけるC型肝炎ウイルス感染の有無について(II 共同利用研究 2.研究成果)

Leishmaniasis is endemic in northern Cameroon. However, the sand fly vectors have not been incriminated. A sand fly species inventory was generated by integrating a number of techniques. Miniature light traps were used for collecting sand flies in a variety of ecotopes found across the area, and a morphological and molecular identification approach for taxonomic confirmation was undertaken. In a pilot survey conducted in September 2012, we captured 687 sand flies, 259 of which were morphologically identified to species level. They represent 14 species of the genera Sergentomyia and Grassomyia. No Phlebotomus spp. were found. A second series of collections was carried out during 2013 in five different environmental setups: two urban, two peri-urban/rural and one sylvatic; 14,036 sand flies (6665 males and 7371 females) were collected. A total of 5926 females and 98 males were morphologically identified to species level, representing 19 species of the genera Sergentomyia, Grassomyia and Phlebotomus, including Ph. duboscqi, a known vector of cutaneous leishmaniasis in the region. Two new taxa were found and are described: Sergentomyia (Sintonius) thomsoni mandarai ssp. nov. and Se. coronula sp. nov. Our study is the first to report the following species in Cameroon: Se. (Sin.) thomsoni (as ssp. nov. mandarai), Se. (Ser.) cincta, Se. (Sin.) affinis ssp. vorax, Se. (Sin.) adami, Se. (Sin.) herollandi, and Se. (Sin.) christophersi. In addition, some morphologically atypical Sergentomyia specimens (combination of Ser. x Sin. traits) were recorded. A checklist of 32 species reports from Cameroon is presented

Oxidative Effects of Potassium Dichromate on Biochemical, Hematological Characteristics, and Hormonal Levels in Rabbit Doe (Oryctolagus cuniculus)

The present study was conducted to evaluate the toxicity induced by the increasing doses of potassium dichromate in rabbit doe. Twenty-eight adult does of 6 months of age were divided into four groups (A, B, C, and D; n = 7), with comparable average body weight (bw). Group A rabbits received only distilled water daily and served as a control, while groups B, C, and D received, respectively, 10 mg/kg bw, 20 mg/ kg bw, and 40 mg/kg bw of potassium dichromate via gavage for 28 days, after which animals were anesthetized with ether vapor and sacrificed. Blood samples were obtained via cardiac puncture and collected without anticoagulant for biochemical dosages and with anticoagulant (EDTA) for complete blood count. Follicle stimulating hormone (FSH), luteinizing hormone (LH), and estradiol (E2) were dosed in serum and in homogenates of ovary with the help of AccuDiagTM ELISA kits from OMEGA DIAGNOSTICS LTD (Scotland, England) while respecting the immuno-enzymatic method. Activities of superoxide dismutase (SOD), glutathione (GSH), catalase (CAT), and concentration of malondialdehyde (MDA) in liver, kidney, ovary and uterus were measured. Hematology revealed a significant (p < 0.05) decrease in mean values of hemoglobin and platelets while white blood cells and lymphocytes showed a significant (p < 0.05) increase in exposed groups. No significant (p > 0.05) difference was registered in monocytes, red blood cells, hematocrits, and plaquetocrits values with respect to the control. No matter the organ considered, no significant (p > 0.05) change was recorded in weight and volume. Nephrotoxicity analysis registered a significant (p < 0.05) increase in urea and creatinine, unlike renal tissue protein, which decreased significantly (p < 0.05). However, hepatotoxicity registered no significant (p > 0.05) variation in aspartate aminotransferase but total protein, alanine aminotransferase, and total cholesterol increased significantly (p < 0.05), while hepatic tissue protein revealed a significant (p < 0.05) decrease. Analysis on reproductive parameters showed a significant (p < 0.05) decrease in ovarian and uterine tissue proteins, as well as in follicle stimulating hormone, luteinizing hormone, and estradiol. Oxidative stress markers recorded no significant (p > 0.05) difference in glutathione reductase except in ovary where a significant (p < 0.05) decrease was seen when compared with the control, while catalase revealed a significant (p < 0.05) decrease, except in liver where there was no significant (p > 0.05) change. Superoxide dismutase and malondialdehyde recorded a significant (p < 0.05) decrease and increase respectively, with respect to the control. Results obtained from this study showed that the reduction process of chromium in tissues may cause the generation of reactive oxygen species, which are involved in hematoxic, nephrotoxic, hepatotoxic, and reproductive toxicity effects

Antouka Super® induced oxidative stress and reproductive toxicity in male Japanese quail (Coturnix coturnix japonica)

Background: Antouka Super® (AS), a combination of insecticide (Pirimiphos-methyl 16% and Permethrin 3%), is one of the most widely used pesticides in agriculture, public health, home and garden, with high potential for human and animal exposure. Objective: The present study was undertaken to evaluate the effect of AS on the serum testosterone, oxidative stress biomarkers, testis histology and fertility of male Japanese quail. Methods: Thirty-two (32) male Japanese quails twenty-eight (28) days were randomly divided into four groups: C0 (control), T1, T2 and T3, exposed daily (gavage) to 0, 37.5, 56.25 and 75 mg of AS/kg body weight (b.w), respectively, for 49 consecutive days and were analysed for fertility. Control and experimental male quails were cohabited, for two days, with untreated female quails and sperm positive female quail were analysed for paternal-mediated toxicity. After completion of fertility studies quails were sacrificed and analysed for reproductive endpoints. Results: There was a dose dependent decrease of the relative weight of testis, epididymis and vas deferens. Additionally, testis total proteins and serum testosterone levels were decreased in AS treated quails (p < 0.05). A decrease of sperm motility, viability and concentration per vas deferens, and an increase of sperm anomalies were recorded in AS exposed quails with respect to the controls. The embryonic and post-embryonic mortality rate were significantly (p < 0.05) higher in group T3 (25.00 ± 3.40% and 31.66 ± 10.22% respectively) than in control group (6.25 ± 3.98% and 9.54 ± 3.72% respectively). The superoxide dismutase (SOD), total peroxidase (POD) and catalase activity (CAT) were significantly (p < 0.05) lower treated than control quails, while the level of malondialdehyde (MDA) was significantly (p < 0.05) higher in groups T1, T2 and T3 (13.00 ± 0.96, 23.50 ± 1.35 and 29.08 ± 1.58 nmol/mg tissues respectively) compared to the control one (9.32 ± 0.67nmol/mg tissues). Histopathological examination of the testes of AS treated quails revealed testicular lesions characterized by moderate to severe degenerative changes of seminiferous tubules, incomplete spermatogenesis and depletion in the germ layers of seminiferous tubules in which immature spermatozoa were hardly seen. Conclusion: From the above study, it can be inferred that AS (56.25 and 75) mg/kg b.w decrease body and relative organ weights and induces testicular lesions. Also, AS increases the level of MDA while it reduces the levels of enzymatic antioxidant biomarkers, serum testosterone and reproductive indices of intoxicated quails and their offspring. However, further work is needed to establish the genetic toxicology and immunohistochemistry of caspase-3 and claudin-1