RESUMEN
Despite several decades of mass drug administration and elimination-related activities, human onchocerciasis still represents a major parasitic threat in endemic regions. Among the challenges encountered by the elimination program is the lack of a suitable diagnostic tool that is accurate and non-invasive. Currently used methods are either invasive or not suitable for monitoring large numbers of patients. Herein, we describe the identification and characterization of Onchocerca volvulus heat shock protein 70 (OvHSP70) as a novel diagnostic biomarker for human onchocerciasis, which can directly be detected in urine samples of infected patients. This nematode-specific antigen was identified through LC-MS after differential SDS-PAGE using urine-derived protein extracts from O. volvulus-infected patients in Cameroon. Polyclonal antibodies generated in rabbits after cloning and expression of OvHSP70 in Escherichia coli reliably differentiated between urine samples from infected- and uninfected patients in a hypoendemic area of human onchocerciasis. These results provide an excellent basis for further development of a non-invasive and scalable diagnostic assay for human onchocerciasis using urine samples. Such a urine-based diagnostic assay will be of major importance for the elimination program of human onchcerciasis in endemic countries.
RESUMEN
OBJECTIVE@#Infectious diseases such as typhoid fever lead to the formation of free radicals which can damage the body. Many medicinal plants have antioxidant molecules that neutralize free radicals. The present work evaluated the antioxidant activity and histopathological effects of the dichloromethane fraction of Dichrocephala integrifolia in Salmonella typhi-infected rats.@*METHODS@#The S. typhi-infected rats concurrently received daily doses of D. integrifolia extract at doses of 25, 50 and 100 mg/kg body weight or ciprofloxacin (5 mg/kg body weight) for 15 days. Body temperature was measured daily during infection and treatment periods. At the end of treatment period, the animals were sacrificed and biological responses including hematological parameters, superoxide dismutase and catalase activities, and glutathione, malondialdehyde and nitric oxide concentrations were evaluated.@*RESULTS@#The elevated body temperature induced by infection was significantly decreased in animals treated with 25, 50 or 100 mg/kg of the extract. Platelet levels decreased slightly in infected rats, while treatment with the dichloromethane fraction of D. integrifolia significantly increased platelet levels; this response was greater than that elicited by ciprofloxacin. The doses of 50 and 100 mg/kg of the dichloromethane fraction of D. integrifolia notably decreased monocyte and neutrophil values. Activity of superoxide dismutase and catalase and levels of glutathione in the tissues of treated animals were increased significantly (P < 0.01), while malondialdehyde and nitric oxide levels were significantly decreased (P < 0.01), following treatment with the dichloromethane fraction of D. integrifolia.@*CONCLUSION@#The results of this study show that the dichloromethane fraction of D. integrifolia has protective effects against a series of pathological conditions initiated by oxidation and tissue damage in the course of a S. typhi infection.
