6320 research outputs found
Sort by
Insecticide susceptibility of Phlebotomus argentipes in visceral leishmaniasis endemic districts in India and Nepal
No full textOBJECTIVES: To investigate the DDT and deltamethrin susceptibility of Phlebotomus argentipes, the vector of Leishmania donovani, responsible for visceral leishmaniasis (VL), in two countries (India and Nepal) with different histories of insecticide exposure. METHODS: Standard WHO testing procedures were applied using 4% DDT and 0.05% deltamethrin impregnated papers. The effect of the physiological status (fed and unfed) of females on the outcome of the bioassays was assessed and the optimal time of exposure for deltamethrin was evaluated on a colony population. Field populations from both countries were tested. RESULTS: Fed and unfed females responded in a similar way. For exposure time on field samples 60 min was adopted for both DDT and deltamethrin. In Bihar, knockdown and mortality with DDT was respectively 20 and 43%. In Nepal almost all sand flies were killed, except at the border with Bihar (mortality 62%). With 0.05% deltamethrin, between 96 and 100% of the sand flies were killed in both regions. CONCLUSIONS: Based on literature and present data 4% DDT and 0.05% deltamethrin seem to be acceptable discriminating concentrations to separate resistant from susceptible populations. Resistance to DDT was confirmed in Bihar and in a border village of Nepal, but the sand flies were still susceptible in villages more inside Nepal where only synthetic pyrethroids are used for indoor spraying. The low effectiveness of indoor spraying with DDT in Bihar to control VL can be partially explained by this resistance hence other classes of insecticides should be tested. In both countries P. argentipes sand flies were susceptible to deltamethri
Ingestion et digestibilité in vivo du Panicum maximum associé à trois compléments: tourteau de Jatropha curcas, tourteau de coton (Gossypium hirsutum) et Euphorbia heterophylla chez le cobaye (Cavia porcellus L.)
No full textThe intake and the in vivo digestibility of Panicum maximum associated with three supplements: Jatophra curcas Cake, Gossypium hirsutum Cake and Euphorbia heterophylla (Euph) in Guinea Pigs (Cavia porcellus L.). The intake and the in vivo digestibility of Panicum maximum associated with three supplements: Jatropha curcas cake, Gossypium hirsutum cake and Euphorbia heterophylla (Euph) in guinea pigs (Cavia porcellus L.) pigs, its association with Panicum maximum could be popularized wherever its abundance has been reported. In order used weed Euphorbia heterophylla in guinea pigs diet, comparative study of the intake and the in vivo digestibility of four treatments, Panicum maximum (Pan), Panicum maximum and Gossypium hirsutum cake (Pancoton), Panicum maximum and Euphorbia heterophylla (Paneuph) and Panicum maximum and Jatropha curcas cake (Panjatro), in male guinea pigs were conducted in Yamoussoukro (Ivory Coast). The means of the intake (g DM/d) were 64.8 ñ 12.5; 74.3 ñ 12.9; 73.7 ñ 17.8 and 69.1 ñ 12.3 respectively for Pan, Pancoton, Paneuph and Panjatro. Pancoton and Paneuph were significantly better ingested than Pan and Panjatro. Euphorbia heterophylla was significantly better ingested than the other two supplements (P< 0.05) and the mean daily weight gain with its association with Panicum maximum of 3.1 ñ 0.6 g/d. The rate of substitution of Panicum maximum by Euphorbia heterophylla was nearly to one (1). The apparent digestibility coefficients (ADC) for dry (68.0 ñ 10.5%) and organic matter (84.1 ñ 5.2%) of Paneuph were significantly higher (P< 0.05) than the ADC's for the other three treatments. Given the nutritional value of Euphorbia heterophylla in guinea pigs, its association with Panicum maximum could be popularized wherever its abundance has been reported
Assessment of a 27-kDa antigen in Enzyme-Linked Immunosorbent Assay for the diagnosis of fasciolosis in Vietnamese patients
No full textSummary Fasciolosis has emerged as an important zoonotic disease in many parts of the world. In recent years, an increasing number of human cases were reported in Vietnam. In this study, the 27-kDa component protein from the excretory/secretory production of adult Fasciola gigantica, purified by high performance liquid chromatography, was assessed in an enzyme-linked immunosorbent assay (ELISA) to detect antibodies against Fasciola spp. for diagnosis of human fasciolosis. The ELISA showed a high sensitivity (100%) and specificity (97.67%) when tested on patients with fasciolosis, other parasitic infections, cholangiocarcinoma and on healthy controls. The assay was applied for diagnosis on 143 patients in the Viet Duc-Hanoi hospital who presented with clinical signs of liver disease and lesions in their livers as shown by imaging techniques. Antibodies were found in 37 (25.9%) of these patients, of whom only 3 shed Fasciola eggs in their stools (2.1%). The excellent response to triclabendazole treatment of 37 sero-positive patients confirmed the diagnosis of fasciolosis. This study demonstrated the diagnostic potential for human fasciolosis of the 27-kDa antigen ELISA. Fasciolosis should be considered in the differential diagnosis of hepatic disease in Vietnam
Rapid diagnostic multiplex PCR (RD-PCR) to discriminate Schistosoma haematobium and S. bovis
No full textSchistosoma haematobium and S. bovis are widespread schistosome species causing human and cattle schistosomiasis, respectively, in Africa. The sympatric occurrence of these two species and their ability to infect the same Bulinus intermediate snail hosts necessitates precise methods of identification of the larval stages. A rapid diagnostic 'mulitplex' one-step polymerase chain reaction protocol (RD-PCR) was developed using cytochrome oxidase subunit 1 (COX1) mitochondrial DNA (mtDNA) to discriminate between S. haematobium and S. bovis. A single forward primer and two species-specific reverse primers were used to produce a polymerase chain reaction (PCR) fragment of 306 bp and 543 bp for S. bovis and S. haematobium, respectively. Serial dilutions were carried out on various lifecycle stages and species combinations to test the sensitivity and specificity of the primers. This RD-PCR proved highly sensitive, detecting a single larval stage and as little as 0.78 ng of genomic DNA (gDNA) from an adult schistosome, providing a cost-effective, rapid and robust molecular tool for high-throughput screening of S. haematobium and S. bovis populations. In areas where human and cattle schistosomiasis overlap and are transmitted in close proximity, this mitochondrial assay will be a valuable identification tool for epidemiological studies, especially when used in conjunction with other nuclear diagnostic markers
The clinical spectrum of Exophiala jeanselmei, with a case report and in vitro antifungal susceptibility of the species
No full textExophiala jeanselmei is clinically redefined as a rare agent of subcutaneous lesions of traumatic origin, eventually causing eumycetoma. Mycetoma is a localized, chronic, suppurative subcutaneous infection of tissue and contiguous bone after a traumatic inoculation of the causative organism. In advanced stages of the infection, one finds tumefaction, abscess formation and draining sinuses. The species has been described as being common in the environment, but molecular methods have only confirmed its occurrence in clinical samples. Current diagnostics of E. jeanselmei is based on sequence data of the Internal Transcribed Spacer (ITS) region of ribosomal DNA (rDNA), which sufficiently reflects the taxonomy of this group. The first purpose of this study was the re-identification of all clinical (n=11) and environmental strains (n=6) maintained under the name E. jeanselmei, and to establish clinical preference of the species in its restricted sense. Given the high incidence of eumycetoma in endemic areas, the second goal of this investigation was the evaluation of in vitro susceptibility of E. jeanselmei to eight conventional and new generations of antifungal drugs to improve antifungal therapy in patients. As an example, we describe a case of black grain mycetoma in a 43-year-old Thai male with several draining sinuses involving the left foot. The disease required extensive surgical excision coupled with intense antifungal chemotherapy to achieve cure. In vitro studies demonstrated that posaconazole and itraconazole had the highest antifungal activity against E. jeanselmei and E. oligosperma for which high MICs were found for caspofungin. However, their clinical effectiveness in the treatment of Exophiala infections remains to be determined
Development and validation of a PCR–RFLP test to identify African Rhipicephalus (Boophilus) ticks
No full textThe cattle tick Rhipicephalus (Boophilus) microplus has recently invaded West Africa and caused anxiety amongst farmers in Ivory Coast, as livestock production was severely affected. The introduction of this tick species has remained unnoticed for several years, as all the members of this genus are very similar in appearance. To overcome the cumbersome morphological identification of the four closely related R. (Boophilus) spp. in the region, a PCR-RFLP test, based on a part of the second internal transcribed spacer ribosomal DNA (ITS2), was developed. The molecular tool was successfully validated with a large number of ticks recently collected from West Africa and that were identified both morphologically and genetically. The tool developed is simple, fast, reliable and reproducible; hence it can be routinely applied for species identification. Copyright 2010 Elsevier B.V. All rights reserved
Application of real-time PCR in Ghana, a Buruli ulcer-endemic country, confirms the presence of Mycobacterium ulcerans in the environment [letter]
No full textThis study reports the first successful application of real-time PCR for the detection of Mycobacterium ulcerans, the causative agent of Buruli ulcer (BU), in Ghana, a BU-endemic country. Environmental samples and organs of small mammals were analyzed. The real-time PCR assays confirmed the presence of M. ulcerans in a water sample collected in a BU-endemic village in the Ashanti Region