Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:1.11.1.7 (peroxidase)
 65,474 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The present study investigated some lectin affinities of human dental pulps, especially of odontoblasts and pulp cells. The materials were obtained from clinically intact teeth that were caries-free, attrition and/or abrasion-free. Mucopolysaccharide staining was carried out with applied PAS and alcian blue (AB) (pH 1.0 and 2.5). Lectins used were Con A, WGA, RCA-1, UEA-1, DBA, SBA, MPA, LFA, HPA, PNA, and GS-1, and the avidin-biotin peroxidase complex method was employed. Some specimens were tested for PNA binding after treatment with sialidase. The following results were obtained: 1) On PAS and AB staining, the pulp tissue was very weakly or borderline positive. 2) Lectin binding in odontoblasts was intensely positive with Con A, WGA, RCA-1, MPA, and LFA, but negative or very weakly positive with the other lectins examined. 3) Lectin localization in odontoblasts was localized diffusely throughout the cytoplasm. 4) On PNA staining, odontoblasts were negative, but changed to positive after treatment with sialidase. 5) Odontoblast processes showed negative or borderline staining with all lectins used in this study. 6) The pulp cells were clearly positive with Con A, MPA, LFA, RCA-1, and SBA and especially LFA showed an intense reaction with the pulp cells. 7) WGA affinity for odontoblasts was very strong but that for pulp cells was very weak. 8) Lectin binding in pulp cells was observed mainly in the processes of the cells. From the above results, it is clear that the lectin binding pattern of odontoblasts differs from that of pulp cells. The data suggest that D-mannose, N-acetyl-D-glucosamine, D-galactose, and N-acetyl-D-galactosamine residues are localized in the odontoblasts and sialic acid is localized in the pulp cells.
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PMID:[Lectin histochemical study on human dental pulp. Special reference to odontoblasts and pulp cells]. 248 77

Administration of benzene to mice causes bone marrow toxicity and elevations in prostaglandin E2 (PGE2), a negative regulator of myelopoiesis. In these experiments, benzene (400 mg/kg; 2 x/day for 2 days) administered to DBA/2 or C57Bl/6 mice decreased bone marrow cellularity and myeloid progenitor cell development (measured as colony-forming units per femur) by 40%. When inhibitors of the cyclooxygenase component of prostaglandin H synthase (PHS) (either indomethacin, 2 mg/kg; aspirin, 50 mg/kg; meclofenamate, 4 mg/kg) were coadministered with benzene, myelotoxicity and the elevation in bone marrow PGE level were prevented. Additionally, when indomethacin (1 microM) was added to cultures of bone marrow cells from benzene-treated mice, myeloid progenitor cell development was the same as the controls. The doses of indomethacin used had no affect on the hepatic conversion of benzene to its major metabolite, phenol. Using purified PHS, indomethacin (10 microM) inhibited the arachidonic acid-dependent oxidation of hydroquinone to p-benzoquinone, a putative reactive metabolite of benzene. Indomethacin (10 microM) had no effect on the H2O2-driven oxidation of hydroquinone catalysed by either PHS-peroxidase or myeloperoxidase. Coadministration of the benzene metabolites, phenol and hydroquinone, has been reported previously to reproduce the myelotoxicity of benzene. In our studies, phenol and hydroquinone (50 mg/kg each; 2 x/day for 2 days) decreased bone marrow cellularity by 40%; however, coadministration of indomethacin (2 mg/kg) or meclofenamate (4 mg/kg) with these metabolites did not prevent the decrease in bone marrow cell number. Our results implicate marrow PHS in mediating the short-term myelotoxicity of benzene.
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PMID:Prevention of benzene-induced myelotoxicity and prostaglandin synthesis in bone marrow of mice by inhibitors of prostaglandin H synthase. 250 82

Bouin-fixed and paraffin-embedded sections from the dorsal skin of Bufo bufo and Xenopus Laevis were subjected to lectin histochemistry. A panel of biotinylated lectins (Con-A, PSA, LCA, UEA-I, DBA, SBA, SJA, RCA-I, BSL-I, WGA, s-WGA, PHA-E and PHA-L) and an avidin-biotin-peroxidase complex (ABC) showed a species-specific compartmentalization of saccharides to certain parts of the epidermis and glandular domains. Some marked histochemical differences between the two examined species adapted to fully aquatic (X. laevis) or semiterrestrial (B. bufo) environments may be relevant of a relationship existing between habitat selection and the glycosaminoglycans content of the skin. In addition the technique used in this paper may be applicable for further studies of the carbohydrate composition in various tissues of lower vertebrates.
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PMID:Comparative lectin-binding patterns in the epidermis and dermal glands of Bufo bufo (L.) and Xenopus laevis (Daudin). 251 85

Receptors of 12 lectins in 25 cases of human hepatocellular carcinomas (HCC) were histochemically investigated by avidin-biotin-peroxidase complex (ABC) method. Liver tissues of five cirrhotic patients and five normal subjects were used as controls. SJA receptor was absent both in HCC and controls, while LCA and PSA receptors were present in all tissues studied here. Receptors of DBA, PHA, PNA, UEAI and SBA which did not bind to normal, cirrhotic and pericarcinomatous liver tissues had the positive rates of 4%, 44%, 16%, 4% and 12% in HCC, respectively. Four lectins which strongly bound to the non-cancer liver tissues had their receptors in 96% (ConA, WGA, RCAI) and 36% (BSAI) of HCC. The pretreatment of tissue sections with neuraminidase abolished most of WGA receptors and exposed some PNA binding sites. There were many differences in lectin distribution between HCC and noncancer liver tissues. The changes of glycoconjugates in HCC were discussed.
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PMID:Changes of glycoconjugates in human hepatocellular carcinoma. 254 84

Lectin-binding pattern in extramammary Paget's disease was studied using seven different lectins (Con A, WGA, RCA-I, PNA, SBA, DBA, and UEA-I) by means of the horseradish peroxidase (HRP)-labeling method. By light microscopy it was observed that Con A, WGA, RCA-I, and DBA stained almost all the extramammary Paget cells, while PNA, SBA, and UEA-I stained only some of them. Normal keratinocytes and tumor cells from other diseases such as mammary Paget's disease, malignant melanoma, squamous cell carcinoma, basal cell epithelioma, Bowen's disease, and seborrheic keratosis were positively stained with Con A, WGA, and RCA-I, but not with DBA except in some of the mammary Paget's cells. By electron microscopy it was observed that DBA stained the cell membrane and the Golgi apparatus of the extramammary Paget cells. The present results suggest that DBA is a specific lectin for glycoconjugates in extramammary Paget cells.
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PMID:Lectin-binding pattern in extramammary Paget's disease by horseradish peroxidase (HRP)-labeling method--specific staining with Dolichos biflorus agglutinin (DBA). 257 74

The purpose of this study is to investigate changes of glycoconjugates in the cancer cells of the urinary bladder by means of immunohistochemical methods. The normal bladder epithelium, cancerous lesions, and non-malignant epithelia of the tumor bearing bladder were examined by staining by avidin-biotin-peroxidase complex methods using blood group isoantigens (BGA) and lectins. The materials were obtained from 48 cystectomy specimens in our hospital in these seven years. Anti-A, B and H monoclonal antibodies were used for detecting BGA. GSI-A4, UEA-1, LTA-M, BPA, DBA and PNA were used as probes for lectins. The changes of glycoconjugates in the cancer cells of the bladder and in non-malignant epithelia of the tumor bearing bladder were studied by using six kinds of lectins. Each lectin binding rates of the primary lesions and the metastasized lesions was comparatively investigated. Positive rates for BGA of the high grade tumor was lower than that of the low grade. In the high grade tumor, GSI-A4, PNA and BPA showed high binding rates, while the DBA binding rate was low. The correlation between the histopathological grading of bladder tumor and the changes of glycoconjugates in the cells was suggestive of cancerous process.
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PMID:[Blood group isoantigen and lectin binding studies in the human bladder cancer]. 266

With the purpose of studying changes in the expression of glycoconjugate structures in urothelium, nine different lectins (PNA, WGA, VFA, GSA II, STA, UEA I, LCA, DBA and HPA) with specificity for mono- or oligo-saccharides were used on formalin-fixed, paraffin-embedded tissue sections from 47 patients who had undergone surgical resection for bladder tumors and on normal urothelial biopsies from 10 patients. The tumors were graded and a lectinohistochemical method using biotinylated lectins and avidin-biotin-peroxidase complex was used to demonstrate the lectin binding. Positive staining reactions of cells in cytoplasm and on membranes were evaluated in the basal, the intermediate, and the luminal cell layers, respectively. In both normal and atypical urothelium lectin binding predominated in the luminal cell layer and decreased towards the basal cell layer. In normal urothelium all lectins stained greater than 66% of the cells in the luminal cell layer in cytoplasm and between 5 and 100% of the cells on membranes depending on the lectin used. A gradual loss of lectin-binding structures was seen with increasing grade of atypia. The range of this decrease varied considerably from one lectin to another, but it was consistently found that the percentage of cells stained in cytoplasm and on membranes decreased. A significantly lower percentage of cells stained in cytoplasm was found in invasive tumor cell-islands compared to normal urothelium. In invasive tumor cell-islands staining of cells on membranes was completely absent, except for HPA lectin that stained less than 10% of the cells. In conclusion, we demonstrate a dramatic decrease in lectin-binding carbohydrate structures associated with urothelial malignant progression.
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PMID:Lectinohistochemistry of human bladder cancer: loss of lectin binding structures in invasive carcinomas. 271 53

Sections from the nasal cavity of 12-day-old Swiss albino mice (NMRI strain) were subjected to lectin histochemistry. A panel of biotinylated lectins (Con A, WGA, s-WGA, PNA, SBA, DBA and UEA I) and a horseradish peroxidase-conjugated lectin (GSA II) showed marked differences in binding to the respiratory and the neuroepithelial cells. SBA (affinity for galactose and N-acetylgalactosamine), PNA (galactose) and WGA (sialic acids and N-acetylglucosamine) labelled the receptor neurons in the olfactory and vomeronasal epithelium. DBA (N-acetylgalactosamine) labelled a subgroup of about 5% of the olfactory receptor neurons, but most neurons in the vomeronasal organ. UEA I (fucose) and s-WGA (N-acetylglucosamine) intensely labelled the entire nerve cell population in the vomeronasal organ, but in the olfactory epithelium the labelling with these lectins was stratified. In the respiratory epithelium the ciliated cells were labelled with WGA and s-WGA, while the secretory cells bound most of the lectins. Thus different sugars are exposed on the surface of the different types of epithelia in the nasal cavity, providing a basis for selectivity in microbial attacks on these areas.
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PMID:Lectin-binding pattern of neuroepithelial and respiratory epithelial cells in the mouse nasal cavity. 274 57

Administration of biotinylated monoclonal antibodies provides the basis of a simple technique for identifying immunoreactive sites in vivo. Biotinylated anti-type II collagen antibodies were injected intraperitoneally into normal DBA/1 mice. The mice were sacrificed after 96 hr and the front paws removed and decalcified to allow tissue sectioning before snap-freezing. Binding of antibodies in vivo was visualized with affinity cytochemical staining using avidin-biotin-peroxidase complexes. Specific binding of antibodies to cartilaginous structures was seen after injection of 20-500 micrograms biotinylated monoclonal or polyclonal anti-type II collagen antibodies, but not after injection of a biotinylated control antibody. This technique should further the detection and localization studies of tissue components involved in the dynamics of physiological and pathological processes.
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PMID:Demonstration of immunoreactive sites on cartilage after in vivo administration of biotinylated anti-type II collagen antibodies. 291 Oct 8

Benzene is a myelotoxin which affects hemopoietic progenitor cells leading to bone-marrow depression as well as a genotoxin which causes chromosomal abnormalities including micronucleus formation. We have demonstrated previously that benzene administered to DBA/2 or C57B1/6 mice causes bone-marrow depression and increased prostaglandin E2 levels in bone marrow; both of these effects can be prevented by the coadministration of indomethacin, a selective inhibitor of prostaglandin synthase. We report, herein, that benzene (400-600 mg/kg body weight), under conditions where it depresses bone-marrow cellularity, also induces an increase in the frequency of micronucleus formation in polychromatic erythrocytes of C57B1/6 mice which is also prevented by the coadministration of indomethacin at levels that do not inhibit cytochrome P450 or myeloperoxidase. In Swiss Webster wild-type mice doses of benzene from 400 to 1000 mg/kg were without effect on marrow cellularity, but did induce the formation of micronucleated polychromatic erythrocytes which could be prevented by indomethacin. In contrast, DBA/2 mice, a strain highly sensitive to benzene, exhibited significant bone-marrow depression at a dose of benzene of 100 mg/kg body weight. Even at this low dose, benzene is too toxic toward developing erythrocytes to allow the evaluation of micronucleus formation. The frequency of induction of micronucleated polychromatic erythrocytes by benzene thus depends on the strain of mouse used. Furthermore, micronucleus formation appears to be an early and very sensitive indicator of benzene toxicity. A possible role for prostaglandin H synthase in the geno- and myelo-toxicity of benzene is discussed.
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PMID:The prevention of benzene-induced genotoxicity in mice by indomethacin. 292 13


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