Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0017536 (giardiasis)
 1,714 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A 29-Kda cytotoxic molecule of axenically-grown pathogenic Entamoeba histolytica (strain HM1) was purified from an amoebic extract by immuno-affinity chromatography with monoclonal antibodies. Immunoreactivity of the purified 29-Kda molecule altered significantly (p less than 0.01) after exposure to heat or trypsin, but remained unaltered after treatment with sodium metaperiodate. The 29-Kda molecule was recognised by serum from each of 13 patients with amoebic liver abscess. In an ELISA system, the molecule produced significantly higher (p less than 0.01) OD readings with these serum samples than with samples from asymptomatic cyst passers. No serum from healthy subjects or from patients with idiopathic ulcerative colitis or giardiasis had antibodies that reacted with the 29-Kda molecule. The immune response to the 29-Kda amoebic protein in man may indicate a specific role for this molecule in invasive amoebiasis.
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PMID:Immunochemical characterisation of a 29-Kda surface-associated molecule of Entamoeba histolytica and its recognition by serum from patients with amoebiasis. 130 84

Giardia lamblia antigens which react with sera from children with G. lamblia infection were investigated by sodium-dodecyl polyacrylamide gel electrophoresis and immunoblotting. Serum IgG, IgM and IgA response to the antigens were immunochemically characterized. Serum antibodies from all giardiasis patients, but none of the controls, was found to react with a 57-kilodalton antigen. The 57 kDa antigen elicited IgG and IgA but not IgM antibodies. The protein nature of the 57 kDa antigen was demonstrated by loss of antibody recognition after trypsin treatment of G. lamblia trophozoites. Subcellular fractionation of G. lamblia trophozoites followed by SDS-PAGE and immunoblotting showed that the 57 kDa antigen was probably not a component of the cytoskeleton.
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PMID:Serum antibody response in children with Giardia lamblia infection and identification of an immunodominant 57-kilodalton antigen. 185 78

Two surface associated antigens (GLSA-82 and GLSA-56) of axenically grown G. lamblia trophozoites (PI strain) were affinity purified from its sonic extract. Both GLSA-82 and GLSA-56 were heat labile, sensitive to treatment with pronase, trypsin and were also sodium metaperiodate modifiable as assessed by micro ELISA. Lectin binding studies revealed that GLSA-82 specifically bound concanavalin A and pokeweed mitogen, and had alpha-methyl mannoside and n-acetyl-B-d-glucosamine sugar moieties. However, GLSA-56 selectively bound Ricinus communis agglutinin and phytohaemagglutinin, and had B-d-galactose and n-acetyl-B-d-galastosamine as sugar moieties. Human sera obtained during acute G. lamblia infection recognised GLSA-82 and GLSA-56 antigens. However, the antibody levels to GLSA-82 were significantly lower (P less than 0.05) during active giardiasis infection. Such surface associated antigens may be target of antiparasitic immune responses and thus, may modulate disease processes.
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PMID:Characterization of surface associated antigens of axenic Giardia lamblia trophozoites & their recognition by human sera. 202 1

An enzyme-linked immunosorbent assay (ELISA) has been evaluated for copro-diagnosis of giardiasis with anti-trophozoite antibody to capture specific Giardia lamblia stool antigen (GLSA), which was then detected by specific antibody conjugated with horseradish peroxidase. GLSA was demonstrated in stool eluates from all the 24 confirmed cases of giardiasis. None of the stool eluates from apparently healthy subjects or from patients carrying intestinal parasites other than G. lamblia had GLSA. Of the 25 microscopy-negative clinically suspected cases of giardiasis, 17 (68%) patients had GLSA in their stool eluates; these patients responded to anti-giardial therapy. The specific antigen was isolated and affinity-purified by the use of specific antibody; it had a Mr of 66 Kda, and its immunoreactivity was lost after treatment with heat or trypsin but unaltered by metaperiodate. ELISA seems to be a sensitive and specific method for copro-diagnosis of giardiasis, especially in highly suspected cases.
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PMID:Enzyme-linked immunosorbent assay for copro-diagnosis of giardiasis and characterisation of a specific Giardia lamblia antigen in stools. 203 May 2

A 10-year-old mentally retarded girl was sent to our hospital due to generalized edema, vomiting and poor appetite for several days. Serum albumin level was low, but no proteinuria was detected. Her stool was bulky and foul. Stool examination for parasite with formalin-ether concentration method revealed negative result. Trypsin activity test of stool revealed low trypsin activity as compared with normal specimen. Daily fecal fat exceeded upper normal limit. The diagnosis of giardiasis was confirmed by duodenal juice examination. Intestinal histology revealed mild shortening of the villi with increased mononuclear cell infiltration in the lamina propria. The daily stool amount decreased markedly after treatment with metronidazole 250 mg three times a day for 7 days. The edema subsided during the treatment. Serum albumin bevel returned to normal after the treatment. Giardiasis with malabsorption syndrome has often been overlooked in Taiwan. It is advised that in case of malabsorption syndrome giardiasis should be included in the list of differential diagnosis.
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PMID:[Giardiasis with malabsorption syndrome: report of one case]. 227 67

A 10-year-old mentally retarded girl from an asylum in northern Taiwan was diagnosed to have giardiasis with malabsorption syndrome at the Department of Pediatrics, National Taiwan University Hospital in 1983. A survey for giardiasis in 239 children living in the same asylum was therefore performed. Stool specimens were collected from all children, and giardia was examined simultaneously by formalin-ether concentration method and polyvinyl alcohol preservation followed by Trichrome stain. Forty one cases (17.2%) of giardiasis were detected by the former method while 48 cases (20.1%) by the latter method. Abnormally low stool trypsin activity was found in 38 of the 42 cases (90.5%) tested and the activity returned to normal in 50% of patients after successful treatment. Endoscopic examination and intestinal biopsy of upper gastrointestinal tract were performed in 12 cases. Among them, 4 were found to have nodular lymphoid hyperplasia, lymphoid hyperplasia in 7, and increased mononuclear cell infiltration in lamina propria in 7. Forty patients were treated with metronidazole 250 mg three times a day for 5 days. Follow-up stool examinations revealed that 12 children (30%) still passed giardia in their stools 4 months after treatment. Reinfection and inadequate sensitivity of the initial screening test may be used to account for such a high rate of treatment failure.
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PMID:[A survey of giardiasis in an asylum for mentally retarded children]. 263 94

We recently reported the isolation and identification of a Giardia lamblia-specific antigen (GSA 65) that is shed in the stool of giardiasis patients. In the present study, this antigen was affinity purified from sonic extracts of axenically cultured G. lamblia trophozoites and characterized to better understand its biological function and its potential usefulness in the design of coprodiagnostic assays for giardiasis. GSA 65 was resistant to proteolytic digestion with trypsin, chymotrypsin, and protease but was sensitive to treatment with NaIO4 as assessed by Western blotting. This antigen was also stable during prolonged storage at 4 and -20 degrees C in 10% Formalin or distilled H2O as assessed by counterimmunoelectrophoresis. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis and isoelectric focusing gel banding patterns, in conjunction with protein and carbohydrate assays and lectin binding studies, confirmed that this antigen is a highly glycosylated glycoprotein. The resistance of GSA 65 to proteolytic degradation, together with previous immunofluorescence data that indicate the antigen is an integral part of the G. lamblia cyst wall, suggests that this molecule may play a role in maintaining the integrity of the cyst in vivo. The ability of GSA 65 to maintain its antigenic structure under a wide variety of conditions makes it an ideal antigen around which to design sensitive immunodiagnostic assays for giardiasis.
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PMID:Physical and chemical characterization of a Giardia lamblia-specific antigen useful in the coprodiagnosis of giardiasis. 353 98

To define the potential role of complement and antibody in host defense against Giardia lamblia, the effect of human serum on axenically cultured G. lamblia trophozoites was studied. Sera from patients without a history of giardiasis and with no detectable antibody by an indirect immunofluorescence antibody (IFA) assay (IFA titers less than 1:2) killed from 8 to 76% of trophozoites (n = 23 sera). Whereas less than 10% of parasites incubated in phosphate-buffered saline alone were killed, 16 sera killed from 10 to 25% and six sera killed from 25 to 75%. One serum with an anti-G lamblia antibody titer of 1:128 killed greater than 98% of the parasites. The complement dependency of killing was demonstrated by abrogation of the lethal effect when serum was chelated with EDTA (7 mM) or was heat-inactivated (56 degrees C, 30 min), and, in an immunofluorescence assay, by detection of C3 on parasites killed by normal serum. When the classical complement pathway was selectively blocked by using serum chelated with Mg+2 (2 mM)-EGTA (8 mM), or serum congenitally deficient for the second component of complement, there was no killing; thus, killing was dependent on the presence of an intact classical pathway. In each of three sera from donors with negative IFA titers, an absorbable factor specific for G. lamblia, possibly antibody not detected by IFA, was required for classical pathway activation. To determine if alteration of the surface of G. lamblia would render it an activator of the alternative pathway of complement, trophozoites were studied after cell death or after treatment with neuraminidase or trypsin. In MgEGTA-chelated serum, dead trophozoites activated the alternative pathway as determined by consumption of Factor B and deposition of C3 on their surface. In contrast, untreated or enzyme-treated living parasites did not activate the alternative pathway.
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PMID:Susceptibility of Giardia lamblia trophozoites to the lethal effect of human serum. 669 7

Antigen-capture enzyme-linked immunosorbent assay for the detection of Giardia lamblia-specific antigen in stool eluates from clinical subjects employing monoclonal antibody directed at 66-kDa G. lamblia copro-antigen has been evaluated. The G. lamblia copro-antigen was detected in 67% (31 of the 46 cases) of stool eluates from clinical cases, while none of the stool eluates from subjects with other intestinal parasites or from apparently healthy individuals, had detectable levels of G. lamblia copro-antigen. Monoclonal antibodies secreted by clones B4C5 and D3F4 recognised the periodate-sensitive and -insensitive epitopes of 66-kDa G. lamblia specific copro-antigen, respectively. Eight (73%) of the 11 symptomatic cases of giardiasis had trypsin-/periodate-sensitive epitopes of 66-kDa copro-antigen while 9 (92%) of 11 of the symptomatic cases and asymptomatic G. lamblia cyst carriers had trypsin-sensitive periodate-insensitive G. lamblia specific copro-antigen. The data tend to suggest that detection of periodate-insensitive epitopes of G. lamblia copro-antigen would indicate the presence of the parasite while the detection of periodate sensitive epitopes of G. lamblia copro-antigen would suggest symptomatic active giardial infection.
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PMID:Uses and limitations of monoclonal antibodies to Giardia lamblia-specific 66-kDa copro-antigen in copro-immunodiagnosis of giardiasis. 768 67

Giardia lamblia localize and multiply in the small intestine and may cause acute or chronic diarrhoea with malabsorption of fat, protein and other nutrients. Abnormal pancreatic function has been documented in giardiasis and trophozoites directly inhibit pancreatic lipase activity in vitro. The aim of this study was to examine the effect of Giardia trophozoites on pancreatic trypsin, chymotrypsin and amylase activity in vitro. Axenically cultured Giardia trophozoites (Portland-1 stock) were incubated with a range of concentrations of trypsin, chymotrypsin and amylase and enzyme activity assayed over time. Tryptic activity was decreased after incubation with Giardia trophozoites. This reduction was time dependent and linear over the incubation period of 2 h. At a trypsin concentration of 18 BAEE units/ml, there was a 35.5 +/- 4% reduction in enzyme activity after 2 h compared to controls. The total amount of activity lost was proportional to the initial trypsin concentration up to 185 BAEE units/ml. At this initial concentration, the activity was reduced by 46.5 +/- 3 units/ml after 2 h. Above this concentration, little further loss of enzyme activity was seen. To investigate the nature and specificity of this effect, similar experiments were conducted using killed trophozoites and with a related protozoan, Trichomonas vaginalis. No loss of enzyme activity was evident. Media previously incubated for 2 h with trophozoites did not diminish tryptic activity. Trophozoites had no effect on chymotrypsin or amylase activities over the range of concentrations tested.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:The effect of Giardia lamblia trophozoites on trypsin, chymotrypsin and amylase in vitro. 848 60


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