Introducing a simple and economical method to purify Giardia lamblia cysts

Direct microscopic examination of stool to diagnosis giardiasis (wet mount) has low diagnostic value, but immunologic methods (like IFA and especially ELISA) that are based on the determination of parasite antigens in fecal samples (antigen detection) have relatively high sensitivity and specialty. To prepare anti-Giardia lamblia antibodies needed to design diagnostic kits as well as parasite culture and other molecular studies, we require purification of the parasite cysts. In this study, we designed a rapid, simple and inexpensive method to purify parasite cysts from fecal samples of the patients suffering from giardiasis. Initially, fecal samples that the presence of G. lamblia in them was affirmed by direct microscopic observation of cysts were subjected to various purification methods like one- and twophase sucrose gradient isolation, percoll-sucrose gradient isolation, and a modified two-phase method run by 0.85 and 1.5 M sucrose. The first procedure contained some contents of bacteria and small particles of feces. In the second and third procedure, bacteria were almost removed and the cysts were intact but the suspension contained some extras and cellulose particles. The recovery rate for modified two-phase method was 1.5 × 104 cysts for each two grams of fecal sample. In this study, by using and comparing with the results of some other studies, we introduce and run a modified method that in fact is a mélange of them with some changes. So this method could be recommended as a fast, advantageous and simple method in purification of G. lamblia cysts.Key words: Giardia lamblia, cyst, purification

Designing of enzyme linked immunosorbent assay (ELISA) kit for diagnosis copro-antigens of Giardia lamblia

The sensitivity of microscopic examination of fecal samples to recognize Giardia parasites is low. In the methods based on antigen scanning of parasites such as enzyme linked immunosorbent assay (ELISA), copro-antigens of parasite will be traced and diagnosed even if the live parasite is absent in the fecal samples. To design this method, a pure antibody against parasite as well as an antibody conjugated to a proper enzyme is needed. In this study, an anti-Giardia IgG extracted from serum of contaminated rabbit was purified by ion-exchange chromatography and conjugated to the enzyme horse radish peroxidase (HRP). This antibody was used to design direct and indirect ELISA kits to measure conjugation titer. In both direct and indirect ELISA methods, optical densities (ODs) were 1 by using dilution of 1/4000 of conjugation. According to the results of both tests and the success in produced conjugate, it could be proceeded to prepare ELISA kits to diagnose giardiasis infections in various samples.Key words: Enzyme linked immunosorbent assay (ELISA), antibody, copro-antigen, Giardia lamblia

Assessing global patterns in mammalian carnivore occupancy and richness by integrating local camera trap surveys

Aim Biodiversity loss is a major driver of ecosystem change, yet the ecological data required to detect and mitigate losses are often lacking. Recently, camera trap surveys have been suggested as a method for sampling local wildlife communities, because these observations can be collated into a global monitoring network. To demonstrate the potential of camera traps for global monitoring, we assembled data from multiple local camera trap surveys to evaluate the interchange between fine- and broad-scale processes impacting mammalian carnivore communities. Location Argentina, Belize, Botswana, Canada, Indonesia, Iran, Madagascar, Nepal, Norway, Senegal, South Africa, and the U.S.A. Methods We gathered camera trap data, totalling > 100,000 trap nights, from across five continents. To analyse local and species-specific responses to anthropogenic and environmental variables, we fitted multispecies occurrence models to each study area. To analyse global-level responses, we then fitted a multispecies, multi-area occurrence model. Results We recorded 4,805 detections of 96 mammalian carnivore species photographed across 1,714 camera stations located in 12 countries. At the global level, our models revealed that carnivore richness and occupancy within study areas was positively associated with prey availability. Occupancy within study areas also tended to increase with greater protection and greater distances to roads. The strength of these relationships, however, differed among countries. Main conclusions We developed a research framework for leveraging global camera trap data to evaluate patterns of mammalian carnivore occurrence and richness across multiple spatial scales. Our research highlights the importance of intact prey populations and protected areas in conserving carnivore communities. Our research also highlights the potential of camera traps for monitoring wildlife communities and provides a case study for how this can be achieved on a global scale. We encourage greater integration and standardization among camera trap studies worldwide, which would help inform effective conservation planning for wildlife populations both locally and globally