Entamoeba histolytica and Entamoeba dispar infection in children in Bangladesh.
Explore the source record for details and available documents.
Animals↗
Biomedical subjects
R Haque
Publications and source records attributed to R Haque.
[Pneumosinus dilatans frontalis. Etiology, symptoms and surgical technique].
BACKGROUND: Pneumosinus dilatans of the frontal sinus is a very rare condition in which deformity is caused by progressive enlargement of the brow ridges and lower forehead. PATIENTS: Etiology of the reported two cases was unknown although some hypotheses have been presented. RESULTS AND CONCLUSIONS: We corrected the aesthetic deformity using an osteoplastic flap and removing horizontal bone chips from the anterior wall of the frontal sinus. Postaoperative results were satisfactory. In one case, obliteration of the sinus with fat was necessary, because of polypous mucosa.
Adult↗
Antibody isotype responses to antigens of Ascaris lumbricoides in a case-control study of persistently heavily infected Bangladeshi children.
Antibody responses to Ascaris lumbricoides worm antigens were examined by ELISA in a case-control study of 2 groups of Bangladeshi children, one of which had been shown over a period of 12 months to be consistently lightly infected (controls) and the other consistently heavily infected (cases). The children showed a wide range in intensity of infection; children identified as cases were on average 4 times more heavily infected than the controls. There were no significant differences in weight, height, mid-upper arm circumference and skinfold thickness between the case or control subjects at the time blood samples for analyses by ELISA were collected. Children with repeatedly heavy infections with A. lumbricoides had higher concentrations of antibody isotypes to the antigens of A. lumbricoides than children who are repeatedly lightly infected. IgG1, IgG4 and IgE to worm antigens occurred in significantly higher concentrations in heavily infected subjects. This suggests that these antibody responses simply reflect the intensity of infection and may not play a significant role in protecting against heavy infections.
Adult↗
Rapid diagnosis of Entamoeba infection by using Entamoeba and Entamoeba histolytica stool antigen detection kits.
Humans are infected by two morphologically identical species of Entamoeba: Entamoeba histolytica causes amebic colitis and liver abscess, and Entamoeba dispar is noninvasive. Several weeks of culture and isoenzyme (zymodeme) analysis are required to differentiate E. histolytica from E. dispar. Here we report a field trial of commercial antigen detection kits designed to rapidly detect and differentiate E. histolytica from E. dispar in stool specimens. Stool specimens from 202 patients with diarrhea were examined for E. histolytica and E. dispar by microscopy, culture, and antigen detection. Compared with culture, microscopic identification of the E. histolytica-E. dispar complex was 60% sensitive and 79% specific, while the screening antigen detection test for the E. histolytica-E. dispar complex was 80% sensitive and 99% specific. Differentiation of E. dispar from E. histolytica by the E. histolytica-specific test was 95% sensitive and 93% specific compared with zymodeme analysis. We conclude that the antigen detection test for the E. histolytica-E. dispar complex is more sensitive and specific than microscopy and that the E. histolytica-specific antigen detection test is as reliable and much more rapid than zymodeme analysis for the differentiation of E. histolytica from E. dispar.
Animals↗
From soil to brain: zinc deficiency increases the neurotoxicity of Lathyrus sativus and may affect the susceptibility for the motorneurone disease neurolathyrism.
Zinc deficiency and oversupply of iron to the roots of grass pea (Lathyrus sativus) induce increases in the content of the neurotoxin beta-L-ODAP (3-oxalyl-L-2,3-diaminopropanoic acid) in the ripe seeds. The transport of zinc to the shoots is enhanced by the addition of beta-L-ODAP. The neurotoxin of L. sativus is proposed to function as a carrier molecule for zinc ions. Soils, depleted in micronutrients from flooding by monsoon rains (Indian subcontinent) or otherwise poor in available zinc and with high iron content (Ethiopian vertisols), may be responsible for higher incidence of human lathyrism, one of the oldest neurotoxic diseases known to man. A role for brain zinc deficiency in the susceptibility for lathyrism is postulated.
Amino Acids, Diamino↗
Diagnosis of amebic dysentery by detection of Entamoeba histolytica fecal antigen by an invasive strain-specific, monoclonal antibody-based enzyme-linked immunosorbent assay.
An invasive strain-specific monoclonal antibody against Entamoeba histolytica has been used in a capture enzyme-linked immunosorbent assay (ELISA) for the detection of invasive E. histolytica fecal antigen in clinical specimens and for the diagnosis of amebic dysentery in patients from Bangladesh. The fecal antigen capture ELISA (FAC-ELISA) did not cross-react with other parasite species in the clinical specimens or with noninvasive E. histolytica present in those specimens and in experimentally seeded stools. The limit of detection of the assay for invasive E. histolytica crude antigen diluted in phosphate-buffered saline or in stools was 0.58 and 3.9 micrograms/ml, respectively, which is the equivalent of approximately 72 and 487 E. histolytica trophozoites per well, respectively. The sensitivity, specificity, and efficiency of the FAC-ELISA were 87, 100, and 98%, respectively, for the detection of invasive E. histolytica antigens and 100, 100, and 100%, respectively, for the diagnosis of amebic dysentery. The FAC-ELISA is a potential alternative for the field diagnosis of amebic dysentery and for epidemiological studies to define the distribution of invasive E. histolytica.
Animals↗
Value of microscopy in the diagnosis of dysentery associated with invasive Entamoeba histolytica.
AIMS: To assess the reliability of the detection of erythrophagocytic amoebic trophozoites in stool samples in the diagnosis of dysentery associated with invasive Entamoeba histolytica. METHODS: Amoebic culture was carried out on single stool samples collected from patients from Mexico, Colombia, and Bangladesh. The stools had been examined by light microscopy. Amoebic dysentery was diagnosed when erythrophagocytic E histolytica trophozoites were observed in a case of bloody diarrhoea. E histolytica isolates were characterised by isoenzyme electrophoresis and results correlated with microscopical findings in stools. Statistical analysis was performed using the chi 2 test. RESULTS: Where erythrophagocytic amoebae had been observed in dysenteric stool specimens the E histolytica phenotype was invariably invasive (p < 0.0001). Observation of erythrophagocytic amoebae in dysentery is 100% specific and predictive of infection with invasive E histolytica. When amoebic culture-positive cases only are considered it is 96% sensitive. In this study E histolytica of zymodeme XIV was more commonly associated with amoebic dysentery than zymodeme II. There was no significant difference between the carriage rate of invasive and non-invasive E histolytica in non-dysenteric diarrhoea. Asymptomatic subjects carried non-invasive E histolytica more frequently than invasive E histolytica. Patients with non-amoebic dysentery, when shown to be infected with E histolytica, carried non-invasive strains (12%). CONCLUSIONS: Sensitivity and specificity of microscopical examination of a single stool specimen for diagnosing amoebic dysentery is very high; intestinal carriage of invasive E histolytica detected by culture is not necessarily an indication of active disease as patients with diarrhoea and asymptomatic subjects shed invasive and non-invasive E histolytica. There are possibly two subpopulations of invasive E histolytica with different pathogenic potential which can be differentiated by zymodeme analysis.
Animals↗
Resistance pattern of Pseudomonas aeruginosa occurring in northern part of Bangladesh.
Explore the source record for details and available documents.
Anti-Bacterial Agents↗
Short report: detection of Entamoeba histolytica and E. dispar directly in stool.
Current diagnosis of Entamoeba histolytica infection requires the direct microscopic identification of the parasite, a technique that is insensitive and cannot distinguish pathogenic E. histolytica from noninvasive E. dispar. Enzyme-linked immunosorbent assay (ELISA) antigen detection tests were developed to distinguish E. histolytica from E. dispar infection in stool specimens. The ELISA result for E. histolytica antigen was positive in 26 of 27 E. histolytica-positive stool specimens, three of 25 E. dispar-positive stools, and one of 30 stools with other or no intestinal parasites, giving a specificity and sensitivity for the detection of E. histolytica infection of 93% and 96%, respectively. The assay result used to detect both E. dispar and E. histolytica was positive in 26 of 27 E. histolytica-positive stools, 19 of 25 E. dispar-positive stools, and one of 30 stools negative by microscopy and culture for Entamoeba, giving a specificity and sensitivity of 97% and 87%, respectively. Because these ELISAs can be completed in several hours, they offer promise as rapid and sensitive means of detecting amebic infection.
Animals↗
Diagnosis of pathogenic Entamoeba histolytica infection using a stool ELISA based on monoclonal antibodies to the galactose-specific adhesin.
Monoclonal antibodies (MAbs) directed against pathogen-specific epitopes of the galactose adhesin of Entamoeba histolytica were used in an ELISA to detect antigen from pathogenic E. histolytica. Single stool specimens from 74 patients in Bangladesh were used. The ELISA for pathogenic E. histolytica was positive in all 12 stool specimens with pathogenic amebae subsequently cultured, in no stool specimens with nonpathogenic E. histolytica and in 2 of 40 stools with other or no intestinal parasites detected. Specificity and sensitivity of the assay for pathogenic E. histolytica were 97% and 100%, respectively. These preliminary data offer promise for an ELISA using MAbs to the galactose adhesin as a rapid and sensitive means to detect the presence of pathogenic E. histolytica infection in stool specimens.
Animals↗
A monoclonal antibody for distinction of invasive and noninvasive clinical isolates of Entamoeba histolytica.
Approximately 10% of the world population is infected with Entamoeba histolytica, but only 10% of the carriers develop symptomatic amebiasis. This discrepancy could be explained by the genotypic differences between the morphologically indistinguishable invasive and noninvasive strains of E. histolytica currently identified by zymodeme analysis, a technique that is unsuitable for routine diagnostic laboratories. Here we report the production of a monoclonal antibody against E. histolytica and its use in an immunofluorescence assay to identify invasive isolates cultured from stool samples of infected patients in several regions where amebiasis is endemic: Bangladesh, Colombia, and Mexico. After testing a total of 88 E. histolytica isolates, the correlation between zymodeme characterization and the immunofluorescence assay with the invasive isolate-specific monoclonal antibody was 100%. The epitope detected by the invasive isolate-specific monoclonal antibody resides in a previously undescribed internal protein with molecular masses of 84 and 81 kDa in axenic and polyxenic E. histolytica strains, respectively.
Animals↗
Further diagnostic use of an invasive-specific monoclonal antibody against Entamoeba histolytica.
Genotypic differences between invasive and non-invasive E. histolytica could explain the 1:10 ratio of symptomatic/asymptomatic infection worldwide. Currently, zymodeme analysis is used to differentiate invasive from non-invasive E. histolytica strains but the technique is cumbersome and expensive. In accordance with the WHO research priorities for amebiasis we report here the further use of an invasive-specific monoclonal antibody against E. histolytica in immunofluorescence, to identify isolates cultured from stool samples of patients from three geographically distant endemic regions: Bangladesh, Colombia and Mexico. We tested 107 E. histolytica isolates and the correlation between zymodeme characterization and the immunofluorescence assay was 100%.
Animals↗
Zymodemes of Entamoeba histolytica in Dhaka, Bangladesh.
Stool samples containing Entamoeba histolytica were obtained from two sources: an urban hospital and an urban slum. Using the enzyme patterns of three enzymes (E.C.2.7.1.1 hexokinase, E.C.5.3.1.9 glucose phosphate isomerase and E.C.2.7.5.1 phosphoglucomutase) stained after cellulose acetate electrophoresis, four zymodemes (I, II, XIV and XVI) were identified in 71 isolates. Zymodemes considered to be pathogenic (II and XIV) were identified from 31 of 34 isolates from the urban hospital, and these zymodemes were strongly associated with dysentery and trophozoites containing ingested red blood corpuscles. Blood visible to the naked eye was more commonly seen in stools from which zymodeme XIV was isolated than in those containing zymodeme II (P less than 0.001). Zymodemes considered to be non-pathogenic (I and XVI) were identified in 34 of 37 isolates from slum dwellers and were not associated with blood in the stools.
Animals↗
Purification of a mucopolysacharidase from Bacteroides distasonis.
A mucopolysaccharidase derived from a pathogenic strain of Bacteroides distasonis was isolated and purified by fractionation with cold acetone and ion-exchange chromatography on DEAE-cellulose, pH 8.0. Three detectable enzyme activities from concentrated supernatant filtrates were obtained in a fraction precipitated by three volumes of cold acetone; these were DNAase, hyaluronidase and chondroitinase-like activity. Separation of the DNAase was achieved by ion-exchange chromatography. Fractions designated as purified mucopolysaccharidase contained both hyaluronidase and chondroitinase-like activity.
Bacteroides↗
Partitioning of staphylococcal delta haemolysin.
The behaviour of the biologically active components present in crude delta haemolysin was followed during various fractionation procedures utilised in the purification of delta haemolysin. Most chromatographic techniques yielded multiple peaks of delta haemolysin. None of the procedures completely separated delta haemolysin from the other components of crude culture filtrates. Efforts to purify delta haemolysin should be renewed.
Carboxymethylcellulose Sodium↗
Chemodynamics: transport and behavior of chemicals in the environment--a problem in environmental health.
In the manufacture and use of the several thousand chemicals employed by technological societies, portions of these chemicals escape or are intentionally introduced into the environment. The behavior, fate, and to some extent the effects produced by these chemicals are a result of a complex interaction of the properties of the chemical with the various processes governing transport, degradation, sequestration, and uptake by organisms. In addition, such processes as adsorption, evaporation, partitioning, and degradation are influenced by ambient conditions of temperature, air movement, moisture, presence of other chemicals, and the concentration and properties of the subject chemicals. These influence the level and extent of exposure to these chemicals that man might receive. Study of the physiochemical properties and extent of exposure to these chem;cals that man might receive. Study of the physiochemical properties of compounds in relation to these various processes has provided a basis for better understanding of the quantitative behavior. Such information is useful in development of predictive models on behavior and fate of the chemicals in relation to human exposure. Beyond this, it provides information that could be used to devise procedures of manufacture, use, and disposal that would minimize environmental contamination. Some of the physical principles involved in chemodynamics are presented in this review.
Animals↗
Studies on the adsorption of selected polychlorinated biphenyl isomers of several surfaces.
The adsorption-desorption characteristics of three selected PCB isomers on a soil and some of its constituents have been determined. The extent of adsorption for all surfaces follows the sequence hexachloro greater than tetrachloro greater dichloro for the isomers chosen. For an individual isomer, the adsorption rates increase in the following sequence: Del Monte, sand, illite clay, Woodburn soil, and humic acid. These results are discussed relative to environmental transport of the chemicals.
Adsorption↗
Studies on the vapor behavior of selected polychlorinated biphenyls.
The vapor loss of several PCB isomers from stainless steel planchets surfaces has been studied. Experiments were carried out under two different conditions. In one case, the vapor loss was observed from 2 molecular layers of PCB, while in the other series, the loss from approximately 200 molecular layers was observed. In both cases the loss of PCB from the surface was substantial, although the controlling mechanism of vapor loss was different. In the first case, the transport was approximated by a simple first order rate law, whereas in the latter case, it was a diffusion controlled process. In general, the vapor loss decreased with increasing number of chlorine atoms present in the isomer. The 4,4(1)-dichlorobiphenyl showed a deviation as compared to others indicating that such factors as the electronic distribution, position of chlorine atom on the biphenyl ring and symmentry of the molecule are also important in discussing the vapor transport.
Chemical Phenomena↗