Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0027960 (mole)
 21,279 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Ten cases of melanoma and 5 ocular nevus were studied with the peroxidase-antiperoxidase method with S100 protein. All the cases showed positivity for this protein, this is why we can advise its use in the diagnosis of these entities.
 ...
PMID:Value of the S100 protein in the study of nevus and ocular melanomas. 362 5

We have studied the expression of involucrin in a variety of keratinization disorders, mostly of genetic origin using an avidin-biotin-peroxidase technique. In normal human epidermis 25% of the living epidermis was labelled. The diseases studied fell into two groups. Diseases with greatly increased involucrin staining including collodion baby (38%), Darier's disease (49%), Flegel's disease (56%), erythrokeratoderma variabilis (60%), epidermal naevus with epidermolytic hyperkeratosis (45%) and congenital bullous (58%) and non-bullous (44%) ichythyosiform erythroderma; and diseases with normal or slightly increased staining, including ichthyosis vulgaris (27%), X-linked ichthyosis (25%), confluent and reticulate papillomatosis (27%) and simple epidermal naevus (28%). These results demonstrate that involucrin expression is altered in some keratinization disorders and suggest that in such conditions cellular functions other than keratin metabolism are also affected.
 ...
PMID:Involucrin expression in keratinization disorders of the skin--a preliminary study. 367 94

Fifteen halo nevi were stained for the presence of S100 protein by an unlabelled antibody peroxidase-antiperoxidase method. S100 protein was clearly identifiable within nevus cell nests in the inflammatory infiltrate. The presence of this substance helped to identify nevus cells in dense inflammatory infiltrates and confirm the histologic diagnosis of halo nevus.
 ...
PMID:Delineation of nevus cell nests in inflammatory infiltrates by immunohistochemical staining for the presence of S100 protein. 388 90

Aerobic or anaerobic degradation of glucose by Streptococcus dysgalactiae and Streptococcus uberis yielded products qualitatively similar to those observed previously for Streptococcus agalactiae. There were, however, quantitative differences. Though acetoin was formed during aerobic growth of Streptococcus uberis, there was none with Streptococcus dysgalactiae. Differences between Streptococcus dysgalactiae and Streptococcus uberis in their aerobic metabolism of glucose was in lower oxygen consumption (.5 mol/mol of glucose), greater conversion of glucose to lactic acid, and lower molar growth yields with Streptococcus uberis. Cell suspensions of Streptococcus uberis had strong peroxidase activity, and no hydrogen peroxide accumulated during the respiration on glucose. With Streptococcus dysgalactiae, there was more oxygen consumed during growth (1.5 mol/mol of glucose used), greater conversion of glucose to acetic and formic acids and carbon dioxide, and a cell yield of about 6 g of dry cells more per mole of glucose than with Streptococcus uberis. This increase in molar growth yield with Streptococcus dysgalactiae over Streptococcus uberis could be nearly all accounted for by differences in the amount of substrate level adenosine triphosphate generated. Cell suspensions oxidizing glucose accumulated hydrogen peroxide and showed no peroxidase activity. Streptococcus dysgalactiae showed the same growth relationships in three milk media as Streptococcus agalactiae, although growth and acid formation values were much lower. Growth inhibition by the lactoperoxidase complex was reversed with cystine. Acid formation by Streptococcus uberis was decreased by the lactoperoxidase complex and increased by the addition of cystine; however, neither appeared to affect the growth of the organism.
 ...
PMID:Physiological characteristics of Streptococcus dysgalactiae and Streptococcus uberis and the effect of the lactoperoxidase complex on their growth in a chemically-defined medium and milk. 391 77

Dithionite causes the depletion of dioxygen from suspensions of erythrocytes by reduction of the external dioxygen and not by diffusion into the cell. The molar enthalpy for the reduction shows a small difference with respect to the values found for free hemoglobin; and the normal stoichiometry of 2 moles dithionite/mole dioxygen found there is not observed with erythrocytes. At low hematocrit, the stoichiometry is 2.6:1 and decreases to 1.5:1 at high hematocrit. The change is not due to differences in the hemoglobin saturation or to an inability of dithionite to reduce all dioxygen present at the higher hematocrit. Neither catalase nor peroxidase added to the extracellular volume significantly alters the stoichiometry or the enthalpy of dioxygen reduction by dithionite. Addition of superoxide dismutase, however, restores the normal stoichiometry at high hematocrit and further increases the stoichiometry at low hematocrit. The calorimetrical signal of hydrogen peroxide, clearly seen with free dioxygen, is not present with erythrocytes. In all these cases the total heat evolved is the same.
 ...
PMID:Calorimetric studies of oxyhemoglobin dissociation. II. Erythrocytic oxygen depletion by sodium dithionite. 397 82

An enzyme-linked immunosorbent assay (BA-ELISA) involving use of biotin-labeled anti-rabbit IgG and avidin-labeled horseradish peroxidase was developed for the measurement of O6-methyl-2'-deoxyguanosine (O6-MedGuo). Up to 5 micrograms of methylated DNA was enzymatically hydrolyzed, and the extent of inhibition of binding of immobilized O6-MedGuo-bovine serum albumin to rabbit anti-O6-MedGuo was measured. Fifty percent inhibition of antigen-antibody binding was achieved with 2.5 pmole of of O6-MedGuo. Separation of O6-MedGuo from unmodified nucleosides by high-performance liquid chromatography (HPLC-BA-ELISA) allowed detection of 700 fmole O6-MedGuo in 1 mg of DNA. Among the tobacco-related carcinogens, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) is one of the most potent. In F344 rats it induces nasal cavity, lung and liver tumors. Four hours after a single IV injection of NNK to F344 rats (87 mg/kg body weight), O6-MedGuo was present in target organs (mumole O6-MedGuo/mole dGuo) (nasal mucosa, 219; lung, 13.2; and liver, 34.5) but was not detectable in nontarget organs. F344 rats receiving daily IP injections of NNK (40 mg/kg body weight) for 14 days were sacrificed 24 hr after the last injection. The levels of (O6-Medguo/dGuo) were 7.9 and 11.4 mumole/mole in the nasal mucosa and lung, respectively. In the liver no O6-MedGuo was detected, but 1050 mumole of 7-MeGua/mole Gua was measured by HPLC-fluorimetry. No DNA methylation was observed in the nasal mucosa or liver of F344 rats treated with the nicotine-derived carcinogen N'-nitrosonornicotine.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Study of DNA methylation by tobacco-specific N-nitrosamines. 408 24

1. Static titrations reveal an exact stoicheiometry between various haem derivatives and apoperoxidase prepared from one isoenzyme of the horseradish enzyme. 2. Carbon monoxide-protohaem reacts rapidly with apoperoxidase and the kinetics can be accounted for by a mechanism already applied to the reaction of carbon monoxide-haem derivatives with apomyoglobin and apohaemoglobin. 3. According to this mechanism a complex is formed first whose combination and dissociation velocity constants are 5x10(8)m(-1)sec.(-1) and 10(3)sec.(-1) at pH9.1 and 20 degrees . The complex is converted into carbon monoxide-haemoprotein in a first-order process with a rate constant of 235sec.(-1) for peroxidase and 364sec.(-1) for myoglobin at pH9.1 and 20 degrees . 4. The effects of pH and temperature were examined. The activation energy for the process of complex-isomerization is about 13kcal./mole. 5. The similarity in the kinetics of the reactions of carbon monoxide-haem with apoperoxidase and with apomyoglobin suggests structural similarities at the haem-binding sites of the two proteins.
 ...
PMID:The combination of carbon monoxide-haem with apoperoxidase. 534 72

Peroxidase from the obligate chemosynthetic bacterium Nitrosomonas europaea was purified 1,500-fold, and its properties were examined. The enzyme had a molecular weight of 53,000 and exhibited characteristic absorption maxima at 410, 524, and 558 mmu. The optimal pH and temperature were 7.5 and 44 C, respectively. The peroxidase reaction had an energy of activation of 5,850 cal/mole and required a primary substrate (H(2)O(2)) concentration of 7 x 10(-6)m to proceed at half maximal velocity (K(m)). Reduced cytochrome, c,p-phenylenediamine and pyrogallol acted as hydrogen donors to the purified peroxidase-H(2)O(2) complex. Conditions most suitable for the chemical oxidation of ammonium by H(2)O(2) were determined. The reaction was rapid and produced nitrite but no nitrate. Hydroxylamine was not detected as an intermediate, but it could substitute for ammonium in the system. Neither the rate nor the extent of these reactions was influenced by purified peroxidase, and no evidence was obtained to support a conclusion that the enzyme performs a vital role in the transformation of ammonium to nitrite by N. europaea.
 ...
PMID:Purification and properties of peroxidase from Nitrosomonas europaea. 566 76

The conventional activity of electrophoretically purified horseradish peroxidase toward guaiacol, pyrogallol, 2,6-dimethoxyphenol, and benzidine is abolished by removal of the heme prosthetic group with a mixture of cold acetone and hydrogen chloride. The apoenzyme, though devoid of peroxidase activity, retains its activity as an indoleacetic acid oxidase when it is supplied with 10(-5) mole of manganous ion and 2,4-dachlorophenol per liter. This oxidase activity is cyanide-sensitive; azide also inhibits under specific conditions of both pH and cofactor concentration. Partial restoration of the peroxidase activity by recombination of apoprotein with heme produces no effect on the oxidase activity, except that cofactors are no longer absolutely required. Therefore, it appears that the activity of peroxidase as an indoleacetic acid oxidase need not directly involve the heme prosthetic group, or that manganous ions and dichlorophenol can substitute for the heme group in the reaction between indoleacetic acid and oxidase.
 ...
PMID:Indoleacetic acid oxidase activity of apoperoxidase. 603 67

The presence of myelin basic protein (MBP) within a skin neoplasm would support its derivation from Schwann's cells, since this substance is routinely present within Schwann's cells in the peripheral nervous system. Using a monoclonal antibody prepared against MBP and an unlabeled antibody peroxidase-antiperoxidase assay, we surveyed a variety of skin lesions suspected of being derived from Schwann's cells to determine whether MBP was present. Myelin basic protein was detected within the cytoplasm of cells composing benign solitary schwannoma (neurilemmoma) and neurofibroma, confirming the association of these lesions with proliferation of Schwann's cells. Myelin basic protein was not found in a variety of intradermal and compound nevus cell nevi nor in malignant melanoma. This negative finding supports electron microscopic evidence suggesting that nevus cells have no relationship to Schwann's cells even though some nevus cell arrangements suggest Schwann's cell derivation under the light microscope.
 ...
PMID:A survey of cutaneous neural lesions for the presence of myelin basic protein. An immunohistochemical study. 619 73


<< Previous 1 2 3 4 5 6 7 8 9 Next >>