Larvicidal, miracidiacidal and cercaricidal activities of the Egyptian plant Iris pseudacorus

The larvicidal properties of Iris pseudacorus leaves ethanol extract against second-instar larvae of two mosquito species, Culex pipiens and Aedes caspius [Diptera: Culicidae] were studied. It was observed that the larvicidal effect of this extract was dose dependent. The LC50 values of I. pseudacorus against C. pipiens and A. caspius were 10.36 and 16.43 mg/l within 24 hr, and 7.36 and 10.1 mg/l within 48 hr, respectively. The miracidiacidal and cercaricidal properties of I. pseudacorus extract were directly tested against Schistosoma mansoni miracidia and cercariae and a time- concentration relationship was observed. The concentrations needed to kill all miracidia [LC100] within 5 min., 30 min. and an hr of exposure were 2.7, 1.6 and 0.9 mg/l, respectively

Diagnostic potentials of copro - antigen detection based Elisa compared to microsocopy in intestinal amoebiasis

This study was performed on 93 patients clinically presumed to have intestinal amoebiasis. Stool samples were collected from all of them and subjected to microscopic examination and Entamoeba coproantigens detection using Entamoeba and Entamoeba II tests. Out of 93 clinically positive samples, 51 were found positive by microscopy, while 49 were detected by Entamoeba test as having antigens specific for E. Histolytica/E. dispar [88.24% sensitivity]. Among 49 specimens, 4 were demonstrated as microscopy negative [90.48% specificity]. Entamoeba II test demonstrated 16 specimens having antigens specific for the pathogenic E. histolytica among 49 positive by Entamoeba test, while 33 were positive for nonpathogenic E. Dispar coproantigens

Selective identification of the pathogenic E, histolytica in fresh stool samples using poolymerase chain reaction [PCR]

Stool samples from 93 individuals clinically presumed to have intestinal amoebiasis and subjected to microscopic examination and DNA extraction were collected. The PCR amplification was performed using two sets of primers that differentiated between pathogenic and nonpathogenic Entamoeba DNA. Of the 93 clinically positive cases, 51 were positive by microscopy, while 53 were detected by PCR as having DNA specific for either E. histolytica/ E. dispar. A specificity of 85.71% and a sensitivity of 92.15% were detected by PCR compared wit h microscopy. Among 53 PCR positive specimens, 3 different DNA sequences were demonstrated [8 specimens had DNA sequences specific of E. histolytica, 31 with DNA specific for E. dispar and 14 specimens had mixed DNA sequences for E. histolytica and E. dispar]. PCR was found to be a sensitive and a specific tool

Immunofluorescent detection of both giardia lamblia and cryptosporidium parvum using anti-cryptosporidium oocyst antibodies

In the present work, a polyspecific anti-cryptosporidium oocyst antibodies was used for simultaneous detection of both parasites in human stool. Known positive formalinized human stool specimens of Giardia sp. [n = 10], Cryptosporidium sp. [n=7] mixed infection [n=3] and negative specimens [n = 20] were tested using direct fluorescent technique against the developed antibodies. All positive stool samples for Cryptosporidium and 9 out of 10 Giardia samples or each alone showed fluorescence with variable intensities, while no negative sample harbored other parasites had fluorescence. This newly used polyspecific antibodies offer the advantages of screening of a large number of patients, particularly in outbreaks. Additionally, it represents a cheaper alternative for the most sophisticated and costly immunoassay kits using the monoclonal antibodies with more or less the same diagnostic potentials