Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.2.1.23 (beta-galactosidase)
14,648 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Humidifier lung is a form of exogenous-allergic alveolitis caused by microbial growth in humidifiers and air conditioners. It was the aim of the present study to employ and test the ELISA method as an alternative to antibody determination. 134 employees in a large printhouse equipped with air conditioning plant were examined by us. Specific IgG antibodies against contaminated humidifier fluid were determined by means of a solid-phase radioimmunoassay (protein A RAST) that we had developed further. Alternatively we examined a commercially available ELISA method (Pharmacia IgG-RAST 40; enzyme: beta-galactosidase) and an assay based on protein A peroxidase. The influence of different test conditions was studied. All the methods examined proved suitable for determining the specific IgG antibodies. The commercial beta-galactosidase assay could be adapted to application on microtitre plates in a slightly modified form. In the peroxidase assay it is recommended to use very low serum and enzyme concentrations on account of its high sensitivity. Examination of all the 134 serum samples yielded a high correlation between the results of these two non-radioactive methods and those obtained with the protein-A RAST.
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PMID:[Diagnosis of humidifier lung--comparison of various serologic procedures]. 172 39

Synthetic peptide-alkaline phosphatase conjugates can be used to detect the epitope specificity of (i) antibody-forming cells in vivo by immunocytochemistry; (ii) of antibody secreting cells in vitro by spot-ELISA; and (iii) antibodies in solution by capture ELISA. The availability of synthetic peptide-enzyme conjugates using detector enzymes other than alkaline phosphatase would offer several important advantages, for example in double staining approaches. This paper reports the production of synthetic peptide-horseradish peroxidase conjugates and synthetic peptide-beta-galactosidase conjugates. A peptide of 21 amino acids (SP 29) was coupled to peroxidase in seven differing molar ratios of peptide over peroxidase, ranging from 1:3.4 to 1:575, using periodate oxidation of the enzyme. SP 29 was coupled to beta-galactosidase in four molar ratios ranging from 1.25 to 10, using glutaraldehyde pre-activation of the enzyme. The enzyme activity of the different conjugates was determined, the conjugates were tested in direct capture-ELISA with peptide-specific monoclonal antibodies, and the conjugates were tested in immunocytochemistry to detect peptide-specific B cells. The results show that the conjugates perform best if the peptide is coupled to the enzyme at relatively low molar ratios (1-30). The availability of these new peptide-enzyme conjugates broadens the applicability of synthetic peptides for detection purposes in several assay systems.
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PMID:Synthetic peptide conjugates with horseradish peroxidase and beta-galactosidase for use in epitope-specific immunocytochemistry and ELISA. 172 93

Enzyme labeling of steroids by the p-nitrophenyl ester method was investigated in comparison with the N-succinimidyl ester method. The active ester of a testosterone or 11-deoxycortisol derivative was treated with beta-galactosidase and horseradish peroxidase to give labeled antigens. Various molar ratios of steroid to enzyme and pH conditions were tested. Satisfactory immunoreactivities with an anti-steroid antibody in each enzyme immunoassay system were obtained with the labeled antigens prepared at pH 8.5 by the use of molar ratios higher than 30. The enzyme labeling method should be useful in the case of polar steroids or drugs, since the p-nitrophenyl ester is relatively stable when compared with the N-succinimidyl ester.
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PMID:Enzyme labeling in steroid enzyme immunoassays. Comparison of the p-nitrophenyl ester and N-succinimidyl ester methods. 180 51

A colorimetric solid-phase enzyme immunoassay has been developed which quantifies antibodies to porcine granulosa cell membrane antigens in rabbits immunized with porcine granulosa cells. A cell-free, particulate membrane preparation of porcine granulosa cells was used as coating antigen. A biotinylated second antibody in conjunction with a streptavidin-beta-galactosidase conjugate was utilized to amplify reactivity. The enzyme beta-galactosidase was used due to high background obtained using peroxidase, presumably due to endogenous peroxidase activity of the tissue. Sigmoidal serum dilution curves were obtained with immune rabbit sera indicating that absorbance was related to the concentration of antibodies. Assay activity was reduced by preincubation of immune serum with granulosa cell membranes. Sera from ovariectomized or pre-immune rabbits did not yield any specific binding in the assay. This assay has potential applicability for quantifying antiovarian and antigranulosa cell antibodies in women suspected of having autoimmune premature ovarian failure.
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PMID:A biotin-streptavidin enzyme immunoassay for detection of antibodies to porcine granulosa cell antigens. 180 83

Milk samples were analyzed for their lactose content using flow injection analysis and incorporating immobilized beta-galactosidase or beta-galactosidase/mutarotase and glucose oxidase/peroxidase bioreactors. These enzymes were immobilized, under mild conditions, on to a 2-fluoro-1-methylpyridinium salt-activated Fractogel support. The use of a phosphate buffer (0.15 M) was found to facilitate the rapid mutarotation of alpha-D-glucose and hence could obviate the need for the more expensive mutarotase. The chromogenic agents of choice for monitoring the reaction were 3-methyl-2-benzothiazolinone hydrazone and 3-dimethylaminobenzoic acid. Linearity was observed over the concentration range 16-160 micrograms/ml using lactose standards (r = 0.996). Between 30 and 40 milk samples/h can be analyzed. Comparisons are made with existing HPLC and alkaline methylamine methods for a range of milk matrices. The FIA method consistently gives the lowest standard deviations and coefficient of variation for the various milk matrices analyzed.
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PMID:Flow injection analysis of lactose using covalently immobilized beta-galactosidase, mutarotase, and glucose oxidase/peroxidase on a 2-fluoro-1-methylpyridinium salt-activated Fractogel support. 190 11

Cathepsin D, acid phosphatase, beta-galactosidase, N-acetyl hexosaminidase, leucine aminopeptidase (LAP), lactate dehydrogenase, glucose-6-phosphate dehydrogenase (g-6-PDH), and peroxidase activities were measured in the buccal mucosa of rats kept for 60 days on high-sucrose (68% of sucrose) caries-inducing diet. The findings evidence that this diet observed for 30 days results in a significant elevation of beta-galactosidase and LAP activities and in reduction of peroxidase level. After 60-day diet the examined parameters virtually did not differ from the reference characteristics (a control group kept on 68% starch diet), except elevated g-6-PDH and lowered peroxidase activities. Enzymic activity changes are adaptive and evidence changes in the metabolic processes in the buccal mucosa, that may eventuate in the development of periodontal diseases.
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PMID:[The effect of a high-saccharose diet on the enzymatic activity of the oral mucosa in rats]. 192 95

The activity of some glycosidases, trypsin-like proteinases, peroxidase, inhibitors of beta-glucuronidase and trypsin-like proteinases, as well as the amount of thiocyanates were studied in mixed saliva (MS), dental deposit (DD) and gums (G) of patients with inflammation of the periodontium. In periodontitis the activity of beta-glucuronidase increases fourfold and that of beta-galactosidase doubles in the G; the activity of beta-glucuronidase and its inhibitors increases, the activity of proteinases diminishes, and the antitryptic activity increases in MS, the activity of peroxidase and the amount of thiocyanates change in this case. Along with the peroxidase-H2O2-thiocyanates system, the inhibitors of beta-glucuronidase and trypsin-like proteinases possess properties of unspecific protection, preventing destruction of the periodontal tissues by glycosides and proteinases of microbial and animal origin.
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PMID:[Enzymatic protective systems of saliva in inflammation of the periodontium]. 205 29

Two general methods which exploit the reactivity of sulfhydryl groups toward maleimides are described for the synthesis of oligonucleotide-enzyme conjugates for use as nonradioisotopic hybridization probes. In the first approach, 6-maleimidohexanoic acid succinimido ester was used to couple 5'-thiolated oligonucleotide to calf intestine alkaline phosphatase to provide a 1:1 conjugate in 80-85% yield. The second strategy employed N,N'-1,2-phenylenedimaleimide to cross-link thiolated horseradish peroxidase or beta-galactosidase with a 5'-thiolated oligonucleotide in 58% and 65% yields, respectively. The oligonucleotide-alkaline phosphatase conjugate was able to detect 6 amol of target DNA in 4 h, while the horseradish peroxidase conjugate was found to be 40-fold lower in its sensitivity of detection by using dye precipitation assays.
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PMID:Use of maleimide-thiol coupling chemistry for efficient syntheses of oligonucleotide-enzyme conjugate hybridization probes. 212 71

Entamoeba histolytica--specific serum IgG, IgA, IgM and IgE were assayed in cases of amoebiasis in an endemic area. Patient groups consisted of amoebic liver abscess (n = 18), pre abscess hepatic amoebiasis (n = 22) and amoebic colitis (n = 30). Control subjects comprised 26 asymptomatic cyst passers, 13 giardiasis cases, 20 typhoid patients and 24 non amoebic individuals. Serum IgG was assayed by ELISA: using a monoclonal anti IgG beta-galactosidase (IgG beta-gal) conjugate, a polyclonal avidin biotin horse radish peroxidase (AB-HRP) and a polyclonal anti IgG horse radish peroxidase (IgG HRP) conjugate. IgA and IgM were assayed by the beta-gal ELISA and IgE by AB-HRP. Diagnostically significant IgG and IgA while lower IgM and IgE levels were seen in extra intestinal cases. About 40% of suspected pre abscess hepatic amoebiasis cases were confirmed by antibody estimation. All isotype levels in most dysentery cases were in the range of the controls. Inter assay coefficient of variation and assay specificity/sensitivity are also discussed.
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PMID:Detection of IgG, IgA, IgM and IgE in antibodies in invasive amoebiasis in endemic areas. 213 1

We have developed a simple hybridization method for a DNA segment which is amplified by the polymerase chain reaction: after heat denaturation, the amplified DNA segment with a length of more than 300 bases is adsorbed to microplate wells in the presence of 1.5 M NaCl or 0.5 M ammonium sulfate; the immobilized DNA is hybridized with a biotin-labeled DNA probe; then, the hybridization signal is detected by streptavidin-conjugated beta-galactosidase or peroxidase. This method has several advantages over the conventional dot blot hybridization method: (i) radioisotopes are not used, (ii) synthetic oligonucleotide for the probe is not needed, (iii) the time required for washing of the solid phase is greatly reduced, and (iv) the baking and prehybridization procedures are eliminated. By this method, we were able to detect viral genomes in vesicle specimens from patients infected with varicella-zoster virus.
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PMID:Microplate hybridization of amplified viral DNA segment. 216 86


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