Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.3.1 (alkaline phosphatase)
 47,916 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Binding of epidermal growth factor (EGF) stimulates tyrosyl protein kinase activity of its receptor in the epidermis. This tyrosine residue phosphorylation is thought to be one mechanism by which EGF mediates its effects such as growth stimulation. To modulate a cellular response to EGF, an enzyme which dephosphorylates phosphotyrosyl residues should be present to oppose the effect of the tyrosyl kinase activity of the EGF receptor. We have identified an enzyme in the neonatal mouse epidermis which has the ability to dephosphorylate tyrosyl residues in vitro on EGF receptors. This phosphatase is a soluble protein with a molecular weight greater than 10,000 daltons and shows optimum activity at neutral pH. This epidermal tyrosyl protein phosphatase is not inhibited by tartrate, ATP, and micromolar levels of zinc, but is inhibited by millimolar levels of zinc, magnesium, manganese, and fluoride. Unlike other well-known phosphotyrosyl phosphatases, alkaline phosphatase, and calcineurin, this enzyme is not inhibited by EDTA. Thus, we have identified and partially characterized a possibly unique phosphotyrosyl phosphatase from the epidermis.
J Invest Dermatol 1989 Mar
PMID:Identification of a phosphotyrosyl-protein phosphatase in mouse epidermis. 253 66

This study reviews data on the histogenesis of Kaposi's sarcoma and angiosarcoma derived from clinical features, histology, electron microscopy, enzyme histochemistry, and immunochemistry of both diseases. Their hemorrhagic clinical appearance contrasts the predominantly lymphatic histologic features of vessels in early lesions. Investigations performed to resolve the debate whether these tumors arise from blood vessel or lymphatic endothelium show remarkably similar results for both conditions. Electron microscopy reveals Weibel - Palade bodies in a minority of cases, but features consistent with less well-differentiated blood vessel endothelium may be seen in a greater proportion of tumors. Enzyme histochemistry generally shows absence of adenosine triphosphatase and alkaline phosphatase in tumor cells; a pattern of enzymes similar to that found in normal lymphatic endothelium. Conflicting data arises from the large number of immunohistochemical studies performed on both conditions. Factor VIII-related antigen and Ulex europaeus agglutinin-I have been most frequently employed, but the specificity of these agents for blood vessel endothelium is debatable. Panendothelial markers show consistent labeling of both tumors, but marker studies employing a wide range of monoclonal antibodies specific for blood vessel endothelium have shown occasional positive labeling of tumor cells. A number of studies have claimed absence of labeling with specific blood vessel monoclonal antibodies, but at present no study employing a specific marker for lymphatic endothelium has been reported. Although the demonstration of specific markers for blood vessel endothelium in these tumors has been variable, the data would be compatible with lesions arising from undifferentiated stem cells that proliferate with varying degrees of differentiation toward blood vessel endothelium. An alternative hypothesis for the histogenesis of Kaposi's sarcoma would be one of multicentric hyperplasia containing lymphatic venular anastamoses with elements of both lymphatic and blood vessel endothelium.
J Invest Dermatol 1989 Aug
PMID:Histogenesis of Kaposi's sarcoma and angiosarcoma of the face and the scalp. 266 17

In 10 patients with generalized psoriasis treated by this method biochemical and histological examinations of liver biopsy specimens were done before and after 60 days of the treatment. In some cases a transient rise of A1AT activity, raised activity of alkaline phosphatase and gamma-glutamyltranspeptidase were noted. Histological examinations demonstrated slight hepatocellular damage with microfocal necrosis, fatty infiltration of some cells and increase in the structural elements of cytoplasm.
Przegl Dermatol
PMID:[Laboratory and oligobiopsy studies of the liver in patients with psoriasis treated by the combination of Tigason-PUVA-cignoline (RePUVA+C)]. 269 77

To determine whether liver function tests and clinical and demographic information would predict methotrexate-associated hepatotoxicity, we identified 78 patients who had undergone 147 liver biopsies associated with methotrexate therapy for psoriasis. The joint sensitivity of aspartate aminotransferase, alkaline phosphatase, and total bilirubin values in detecting abnormal results from a biopsy specimen obtained after treatment was .86; the predictive value of negative test results was .93. A logistic regression model significantly predicted the presence of abnormal (grade III or higher) liver biopsy specimen results. The concordance index was .92 (perfect, 1.0). Regression coefficients may be used along with information from a specific patient to calculate the predicted probability of an abnormal result from a liver biopsy specimen after treatment. We conclude that this multivariate risk estimation model significantly predicts the likelihood of positive findings from liver biopsy specimens in this patient population. The clinical use of this model awaits further validation.
Arch Dermatol 1989 Sep
PMID:Detection of hepatotoxicity associated with methotrexate therapy for psoriasis. 277 96

Phospholipase A2 activity is raised in non-lesional psoriatic epidermis compared with normal epidermis. It has been shown that the activity of this enzyme is controlled by an inhibitory protein the inhibitory effect of which is increased by dephosphorylation. Treatment of epidermal extracts with alkaline phosphatase reduced the phospholipase A2 activity, both in normal and in lesion-free psoriatic epidermis. Inclusion of pyrophosphate, a protein phosphatase inhibitor, in the homogenizing medium caused the activity of phospholipase A2 in epidermal extracts from normal and lesion-free epidermis to be raised to the same high level. These results are consistent with the hypothesis that the raised phospholipase A2 activity in psoriatic epidermis is due to hyperphosphorylation of an endogenous inhibitor as a result of defective control of a phosphorylation/dephosphorylation mechanism. The relevance of these findings to other work is discussed.
Br J Dermatol 1988 Mar
PMID:Modulation of phospholipase A2 activity in extracts of lesion-free psoriatic epidermis by alkaline phosphatase and a protein phosphatase inhibitor. 283 3

Plasminogen activators (PA) play an important role in cell migration and tissue degradation. Considering the strong epidermotropism of atypical mononuclear cells in histiocytosis X (HX) skin infiltrates leading to intraepidermal abscess formation, it was the purpose of this study to look for tissue-type PA (t-PA) and/or urokinase-type PA (u-PA) on HX cells. Four monoclonal antibodies against PA were used, employing the alkaline phosphatase anti-alkaline phosphatase (APAAP) technique on cryostat sections from four patients with HX. Twenty percent to 40% of infiltrating cells in the epidermis expressed the t-PA antigen. t-PA+ cells were present in the follicular centers of human tonsil, absent in normal epidermis and scanty in cutaneous infiltrates from mycosis fungoides and lupus erythematosus. Double labeling with anti-PA and T6 (CD1) or S100 protein revealed some of the HX cells to express both antigens (t-PA+ CD1+ or t-PA+ S100+). We conclude that cutaneous infiltrates of HX contain PA+ dendritic cells which are different from normal Langerhans cells and which may be responsible for the strong epidermal alterations in HX.
Arch Dermatol Res 1987
PMID:Cutaneous infiltrates of histiocytosis X contain plasminogen activator-bearing epidermotropic dendritic cells different from Langerhans cells. 311 52

The coexistence of a T-cell lymphoma with a myelodysplatic syndrome seems to be exceptional. In the case reported here the diagnostic problems raised by the appearance of cutaneous nodules in a patient with chronic myeloid leukaemia (CML) were solved by histo-immunological examinations. A 70-year old male patient had been presenting since 1976 with a psoriasis-like skin disease. He was first seen at the Argenteuil hospital in 1984. Physical examination showed psoriasiform finger-like erythemato-squamous lesions, infiltrated plaques and an ulcerated tumoral swelling of the right elbow. A diagnosis of mycosis fungoides was made on histological and immunological examination results. At histology, this epidermotropic lymphoma was peculiar in that the atypical infiltrate was clearly centred on vessels. Electron microscopy confirmed that the vascular walls were invaded by the mycosis cells. Additional examinations showed hyperleucocytosis and myelaemia which were rapidly attributed to a chronic myelocytic leukaemia since the Philadelphia chromosome was present and the leucocytes had a low alkaline phosphatase score. Bone marrow biopsy disclosed a myeloproliferative syndrome of the CML type. Biopsy of a right axillary lymph node showed myelocytic infiltration associated with dermopathic lymphadenitis. There were no circulating Sezary cells, and a search for extension proved negative. From May, 1984 to June, 1985 the patient's CML was treated with busulfan which produced blood and bone marrow remission. The skin lesions were treated first with mechlorethamine, then with topical corticosteroids. Superficial electron therapy was applied to the tumoral lesions.(ABSTRACT TRUNCATED AT 250 WORDS)
Ann Dermatol Venereol 1988
PMID:[A combination of mycosis fungoides and chronic myeloid leukemia. Apropos of a case]. 326 Jul 64

Cryostat sections of skin biopsies from five patients with chronic photosensitivity dermatitis with actinic reticuloid syndrome (PDAR) have been examined immunohistologically by the alkaline phosphatase:anti-alkaline phosphatase staining technique using a panel of 24 monoclonal antibodies against lymphoid cells and their subsets. The lymphoid infiltrates in all cases had an essentially identical cellular composition, containing a mixture of T-lymphocytes, T-cell accessory cells (Langerhans cells) and other types of HLA-DR positive dermal macrophages. In two patients there was an excess of T-helper/inducer cells relative to T-suppressor cells, while in the other three patients the numbers of T-cells in these two subsets were approximately equal. Many of the infiltrating T-cells expressed activation (HLA-DR, interleukin-2 receptor) or proliferation (the Ki67 nuclear antigen, transferrin receptor) associated markers. These data indicate that a T-cell immune response is operative in cutaneous PDAR lesions.
Br J Dermatol 1986 Jan
PMID:Photosensitive dermatitis with actinic reticuloid syndrome: an immunohistological study of the cutaneous infiltrate. 351 Jun 53

Thirty-three patients with alcoholic cirrhosis (AC), selected on widely recognized criteria (16, 57), were investigated prospectively for cutaneous manifestations of zinc deficiency. The patients were divided into 3 groups: group A (n = 12): AC without skin lesions; group B (n = 12): AC with skin lesions responsive to a zinc-free topical treatment or resistant to enteral zinc sulfate intake; group C (n = 9): AC with skin lesions cured by oral zinc replacement therapy alone. The lesions observed in group C were studied microscopically. Data concerning zinc metabolism (Zn concentrations in plasma, red cells, urine and hair; alkaline phosphatase values), biochemical criteria of AC (plasma serum-albumin concentration, IgA/transferrin ratio) and a malabsorption test (xylosemia 120 min after oral absorption of D-xylose 25 g) were compared by the variance analysis method. A control group (D, n = 12) was used as reference. Few cases of cutaneous manifestations of zinc deficiency in AC patients have been published. In more than one half of the 15 or so we found in the literature, an aggravating factor (total parenteral nutrition, digestive tract surgery) had to be taken into account. In this prospective study 9 new cases in which AC was the only cause of zinc deficiency are reported. A clinical picture similar to acrodermatitis enteropathica with peribuccal bullous lesions was observed in only one patient. In all other cases the patients presented with a cracked and reticulated eczema on the extensor aspect of the limbs and (often erosive) in the perianal and genital regions. The eczema was associated with cheilitis, glossitis, stomatitis, alopecia and, seldom, ungual Beau's lines. Disorders of behaviour, diarrhoea and bouts of lever regressing under zinc replacement therapy were frequent. Histology was not very specific, except for the presence of necrotic areas in the stratum germinativum, sometimes associated with small subcorneal pustules containing altered polymorphonuclears. In every case, it was the rapid regression of symptoms under zinc sulfate treatment that confirmed the diagnosis. Plasma zinc concentrations were most significantly decreased in all AC groups as compared to controls (61.2 +/- 19.4 vs 97.8 +/- 10.4 micrograms/100 ml) and also in AC patients with skin manifestations of zinc deficiency as compared to the other AC patients (44.4 +/- 9.2 vs 66.5 +/- 18.8 micrograms/100 ml) table V). Changes in serum-albumin levels and in hepatocellular function were parallel to changes in plasma zinc concentrations.(ABSTRACT TRUNCATED AT 400 WORDS)
Ann Dermatol Venereol 1987
PMID:[Cutaneous manifestations of zinc deficiency in ethylic cirrhosis]. 357 31

We report on a patient with a syndrome characterized by smooth facial papules and nodules; alopecia of the eyebrows, eyelashes, and most body hair; mild alopecia of scalp hair; possibly hypohidrosis; and myasthenia gravis. The clinical, histologic, and immunohistochemical findings are compared with classic and desmoplastic trichoepitheliomas. All fourteen biopsy specimens of the patient showed a lacelike network of basaloid cells with follicular differentiation and a prominent stroma with focal alkaline phosphatase activity, as in fourteen comparison specimens of classic trichoepithelioma. Studies with antikeratin antibodies of various specificities also revealed similar patterns. The tumor cells showed a keratin phenotype characteristic of cells of the infrainfundibular outer root sheath, that is, positive staining with basal keratinocyte markers, negative staining with suprabasal keratinocyte markers, and patchy staining with LP2K (against keratin 19). beta 2-Microglobulin expression was partially or totally absent. It is concluded that the lesions in our patient actually are trichoepitheliomas. The condition may represent a new syndrome that either is closely related to the generalized hair follicle hamartoma (basaloid follicular hamartoma) or is a variant. The finding of generalized trichoepitheliomas with clinical and microscopic alopecia should alert one to the possibility of myasthenia gravis.
J Am Acad Dermatol 1986 Nov
PMID:Generalized trichoepitheliomas with alopecia and myasthenia gravis: clinicopathologic and immunohistochemical study and comparison with classic and desmoplastic trichoepithelioma. 377 60


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