Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0017160 (gastroenteritis)
 11,398 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We studied the macromolecular permeability of segments of jejunum from 2-wk-old piglets after the animals had been experimentally infected with an invasive enteric virus, transmissible gastroenteritis virus. Jejunal segments were mounted in Ussing chambers at stages of the infection, and permeability was measured using three probe molecules of differing molecular weights. In control tissue, permeability to horseradish peroxidase was 2.6 times higher across segments with Peyer's patches than across segments without Peyer's patches, whereas polyethylene glycol 4000 and mannitol permeabilities were the same in patch and nonpatch segments. Twelve hours after infection, when virus had invaded the mucosa causing a structural lesion, and before diarrhea had begun, horseradish peroxidase permeability increased in non-patch-containing segments to equal that across patch-containing tissue. At this early 12-h stage, polyethylene glycol 4000 and mannitol permeation were unchanged in patch-containing segments compared with controls. Ninety-six hours after transmissible gastroenteritis infection, when diarrhea was severe, horseradish peroxidase permeability in patch-free segments had returned to normal and patch-containing tissue permeability was diminished below control levels. Increased macromolecular permeability appears to occur only in the very early invasive stage of this viral enteritis and only in patch-free segments. Any consideration of the immunologic relevance of these complex phenomena must take into account the specialized function of the Peyer's patch regions of the small intestine.
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PMID:Altered jejunal permeability to macromolecules during viral enteritis in the piglet. 391 15

The sensitivity and performance characteristics of enzyme immunoassays (EIA) depend to a great extent on the kinetics of the enzyme-substrate system used as indicator. We labeled a variety of polyclonal and monoclonal immunoglobulins with purified beta-lactamase and used them in sensitive EIA systems for the detection of a number of microbial antigens. Polyclonal antibodies to rotavirus, adenovirus, and Haemophilus influenzae type b polyribitol phosphate and monoclonal antibodies to dengue virus were labeled with beta-lactamase and used to provide sensitive direct EIA systems for the detection of the corresponding antigens. In addition, antibodies directed at animal immunoglobulins were labeled with beta-lactamase and used in indirect EIA for the detection of viral antigens with unlabeled anti-viral monoclonal and polyclonal antibodies. Similarly, avidin from Streptomyces was labeled with beta-lactamase and used to detect viral antigens tested for in an avidin-biotin format. Enzyme immunoassay systems with beta-lactamase-labeled antibodies were also used to detect rotaviral and adenoviral antigens in rectal swab specimens from children with acute gastroenteritis. The sensitivity of the beta-lactamase EIA compared favorably with that of analogous EIA systems using alkaline phosphatase or horseradish peroxidase. The results of a beta-lactamase EIA were easily determined by naked eye and a permanent record of the qualitative results obtained by the use of a standard office photocopier, obviating the need for an expensive colorimeter. Enzyme immunoassays using beta-lactamase have potential as practical assay systems for the detection of a wide range of microbial antigens using monoclonal and polyclonal antibodies.
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PMID:The use of beta-lactamase in enzyme immunoassays for detection of microbial antigens. 609 74

An enzyme-immunoassay (EIA) using polystyrene beads as the solid phase, guinea pig anti-rotavirus or anti-adenovirus immunoglobulin as primary antibody, rabbit anti-rotavirus or anti-adenovirus immunoglobulin as secondary antibody, and horseradish peroxidase-conjugated swine anti-rabbit immunoglobulin as indicator antibody, has been developed for the detection of human rotavirus and adenovirus antigens from stool specimens. A comparison of the developed EIA and radioimmunoassay (RIA) used previously in our laboratory was made with 250 stool specimens from children with acute gastroenteritis. Two specimens were found negative by both rotavirus and adenovirus EIAs but not by RIAs, but in each of these cases confirmatory EIA tests showed them to be false negatives. The confirmatory EIA tests were also necessary in several cases to prove the specificity of the binding or to eliminate non-specific reactions with specimens giving low positive reactions in EIA. The developed EIA was found to be as specific, sensitive and reliable as RIA in the routine diagnosis of rotavirus and adenovirus gastroenteritis provided that appropriate confirmatory tests were included.
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PMID:Comparison of enzyme-immunoassay and radioimmunoassay for detection of human rotaviruses and adenoviruses from stool specimens. 626 39

A four-layer solid phase enzyme-immunoassay (EIA) with antisera against Nebraska calf diarrhoea virus (NCDV) as immunoreagents was developed to detect human rotavirus antigens from stool specimens of patients with acute rotavirus gastroenteritis. Polystyrene beads were used as the solid phase, guinea-pig and rabbit anti-NCDV immunoglobulin as the catching and secondary antibody, and peroxidase-conjugated swine anti-rabbit immunoglobulin as the indicator antibody. A comparison of the developed NCDV-EIA with an identical EIA, using antisera against human rotavirus (HRV-EIA) instead of NCDV antisera, was made with 216 stool specimens positive or negative for rotavirus. A complete agreement was obtained between the two methods provided that appropriate confirmatory tests were included. The developed NCDV-EIA was as sensitive and specific for rotavirus as the HRV-EIA, and it allowed the detection of both established rotavirus types 1 and 2 from stools with equal sensitivity. The difficulties in cultivating human rotavirus in vitro for immunisation and the relative ease of growing NCDV in widely-used continuous cell lines make NCDV a good alternative in the preparation of the highly specific and sensitive rotavirus antisera required in immunoassays, and facilitate the setting-up methods for the routine diagnosis of rotavirus gastroenteritis by EIA or RIA in diagnostic virus laboratories.
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PMID:Human rotavirus antigen detection by enzyme-immunoassay with antisera against Nebraska calf diarrhoea virus. 626 6

The peroxidase-antiperoxidase (PAP) staining technique was used for the detection of transmissible gastroenteritis virus (TGEV) in small intestines of TGEV-infected 8-week-old pigs and in infected McClurkin pig testicle cells by means of light microscopy. The specific-positive reaction was characterized by the presence of many brown granules of various sizes in the cytoplasm of infected cells. Nonspecific granules caused by endogenous peroxidases in the cytoplasm of eosinophils stained by PAP were darker, larger, more round, and more uniform in size than were specific granules. Acetone fixation was superior to fixation with periodate-lysine-paraformaldehyde or 10% formalin. Our results indicate that the PAP staining technique is a sensitive, specific technique for detection of TGEV in the small intestines of pigs.
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PMID:Applications of peroxidase-antiperoxidase staining technique for detection of transmissible gastroenteritis virus in pigs. 628 53

The responses of the interepithelial lymphocytes (IEL) and aggregated lymph nodules (ALN; Peyer's patches) of the small intestines of 8-week-old pigs to transmissible gastroenteritis virus (TGEV) infection were characterized at 12, 18, and 24 hours after pigs were inoculated. There was no significant difference in numbers of IEL between control and TGEV-infected pigs at 12 and 18 hours. However, in pigs examined at 24 hours, there was a significant decrease in the number of IEL in the duodenum and cranial portion of the jejunum and an increase of IEL numbers in the nuclear level of the intestinal epithelium. Number and distribution were unchanged in the middle portion of the jejunum and the ileum. Microscopic changes in TGEV-infected pigs included microulceration of the dome epithelium (DE) over the ALN, especially in the cranial portion of the intestine, and villous atrophy in the entire length of the small intestine. Generally, TGEV was found by means of peroxidase-antiperoxidase staining in areas where microscopic lesions occurred. Electron microscopy revealed that M cells and ordinary microvillus-covered epithelial cells in the DE embraced one or more lymphocytes, and formed a specialized cell complex or DE complex. Most of the lymphocytes in the DE complex possessed many organelles indicative of an active cell state. The TGEV was found between microvilli, in the cytoplasmic vesicles of M cells and microvillus-covered epithelial cells in the DE, and in the cytoplasm of macrophages and lymphocytes and some degenerated cells of unidentified origin in the domes of the ALN. The virus was also commonly found in cytoplasmic vesicles of macrophages and degenerated cells in the intestinal lumen near the base of the dome of the ALN.
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PMID:Changes in gut-associated lymphoid tissues of the small intestine of eight-week-old pigs infected with transmissible gastroenteritis virus. 709 19

Two specific and sensitive, indirect enzyme-linked immunosorbent assays (ELISAs) utilizing a protein G-peroxidase conjugate were developed to detect antibodies to the pseudorabies virus (PRV) and the transmissible gastroenteritis virus (TGEV) in pig sera. Sera from 5,337 pigs, obtained from various abattoirs in South Africa, were tested with both ELISAs. No serological evidence of infection with either PRV or TGEV was found in any of the pigs tested.
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PMID:Pseudorabies and transmissible gastroenteritis: a serological survey in South Africa. 789 99

Rotavirus is an important cause of gastroenteritis in young children. Locally produced antibodies in the intestinal mucosa are proposed to play an important role in the defence against rotavirus infection, but it is not established whether IgA alone can neutralize rotavirus, nor if IgA antibodies recognize epitopes involved in protective immunity. To evaluate whether human IgA plays a role in virus neutralization, serum IgA was purified from nineteen rotavirus seropositive individuals and examined for its neutralizing capacity by a peroxidase focus reduction test. In all nineteen sera IgA neutralizing antibodies against serotype 3 (rhesus rotavirus) were demonstrated. Purified IgA was further investigated and shown not only to neutralize rotavirus in solution but also to neutralize rotavirus already pre-bound to epithelial cells (MA-104). IgA epitope blocking assays with monoclonal antibodies directed against heterotypic epitopes on VP4 and VP7, revealed that IgA antibodies from 4/16 sera recognized epitopes on VP4, while 5/16 sera recognized a VP7 epitope. When whole sera were investigated for comparison 7 and 9/16 sera recognized epitopes on VP4 and VP7 respectively.
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PMID:Neutralization of rotavirus and recognition of immunologically important epitopes on VP4 and VP7 by human IgA. 926 58

Staphylococcal protein-A (SpA) is known to interact with the crystallizable fragment (Fc) of IgG molecules from several species. In the present study, SpA coupled to either fluorescein isothiocyanate (FITC) or peroxidase was used in place of antisera to IgG for the fluorescent antibody (FA) techniques and the enzyme linked immunoassay (ELISA). The SpA conjugates produced low background staining when applied in these techniques, and provide a rapid, highly specific and sensitive means for the identification of viral isolates and the detection of serum antibodies. Moreover, SpA is a single reagent that replaces various preparations of anti-gamma globulin against many species. SpA-FITC conjugate was successfully applied for the identification of pseudorabies virus, hog cholera virus, swine vesicular disease virus, transmissible gastroenteritis virus, porcine parvovirus and porcine enteroviruses. Antibody titers against the mentioned viruses could be determined semi-quantitatively in the indirect FA test with SpA-FITC. In our laboratory the ELISA became a routinely practicable serological test for the detection of antibodies only after we introduced SpA-peroxidase as a marker for the IgG.
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PMID:Enzyme linked immunoassay and fluorescent antibody techniques in the diagnosis of viral diseases using staphylococcal protein-A instead of anti-gamma-globulins. 1561 63

Salmonella enterica serovar Enteritidis has emerged during the last 20 years as the major causative agent of food-borne gastroenteritis in humans and as the major infectious agent on poultry farms, replacing Salmonella enterica serovar Typhimurium as the dominant pathogenic serovar. Because adhesion to gut tissues and colonization of the alimentary tract, mediated in large part by the FimH adhesins located on type 1 fimbriae, is an important stage in the pathogenesis of both serovars, the binding properties of the FimH adhesins from these two enteropathogens were compared. Salmonella Enteritidis FimH protein and the Salmonella Typhimurium low-adhesive variant of this adhesin were expressed in Escherichia coli and the recombinant proteins were analysed for their ability to bind glycoproteins carrying different oligomannosidic structures and different types of eukaryotic cells. In static binding assays (ELISA and Western blotting) both FimH proteins bound equally well to all three tested glycoproteins (RNase B, horseradish peroxidase and mannan-BSA). In addition, no differences were found in the binding specificity of the FimH proteins and intact cells of Salmonella Enteritidis and Salmonella Typhimurium to human colon carcinoma or bladder cancer cells. The presence of the same amino acid residues at positions 61 (glycine) and 118 (phenylalanine) and the similar binding properties of these two adhesins suggest that the newly described FimH protein of Salmonella Enteritidis represents the low-adhesive variant found in Salmonella Typhimurium. To study the binding specificity of Salmonella Enteritidis FimH protein further, direct kinetic analysis using surface plasmon resonance was performed. With this method it was found that Salmonella Enteritidis FimH adhesin bound with the highest K(d) value to high-mannose type N-glycans carried by RNase B; about 100 times lower K(d) values were obtained in the interactions with mannan-BSA and horseradish peroxidase.
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PMID:Functional characterization of the FimH adhesin from Salmonella enterica serovar Enteritidis. 1662 51


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