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  • 1
    ISSN: 1432-1440
    Keywords: Chronic hepatic porphyria ; Porphyria cutanea tarda ; Uroporphyrinogen decarboxylase defect ; Hereditary and non-hereditary disturbance ; Liver and erythrocytes ; Chronic liver disease ; Family studies ; Chronische hepatische Porphyrie ; Porphyria cutanea tarda ; Uroporphyrinogen-Decarboxylasedefekt ; hereditäre und nicht-hereditäre Störung ; Leber und Erythrozyten ; chronischer Leberschaden ; Familienstudien
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Die chronische hepatische Porphyrie (CHP) als chronische hepatische Störung des Porphyrinstoffwechsels ist mit einem chronischen Leberschaden regelmäßig assoziiert, kommt in latenten und manifesten Phasen vor und führt bei ihrer klinischen Manifestation zu Hautsymptomen: Porphyria cutanea tarda. Die primäre enzymatische Störung betrifft die Uroporphyrinogen-Decarboxylase (UD; EC 4.1.1.37). Das Enzym wurde bei 107 Patienten mit „sporadischer“ CHP (29 Frauen, 78 Männer) in den Erythrozyten, darunter bei 17 CHP-Patienten (12 latent, 5 manifest) auch im Lebergewebe untersucht. Die hepatische UD-Aktivität war in allen Fällen um 39 bis 57% gegenüber Kontrollen vermindert (p〈0,001). Die Aktivität der UD in den Erythrozyten in 47 Fällen (44%) um 30 bis 55% gegenüber den Kontrollen erniedrigt (p〈0,001). In dieser Gruppe befanden sich 70 Patienten (darunter 30% Frauen) mit klinisch manifester CHP, von denen 43% (12 Frauen, 18 Männer) eine deutlich herabgesetzte UD-Aktivität in den Erythrozyten gegenüber einer Kontrollgruppe (n=96) aufwiesen (p〈0,001). Bei Patienten mit diesem Enzymbefund wird eine hereditäre Anlage angenommen, die erst im Zusammenwirken mit einem Leberschaden, mit Alkohol und/oder östrogenen zu pathobiochemischen und klinisch-dermatologischen Symptomen führt. Haut- und Leberbefunde sind bei der hereditären und nicht-hereditären Form der CHP nicht verschieden. Familienstudien bei der hereditären CHP lassen einen autosomal dominanten Erbgang des Enzymdefekts in den Erythrozyten und latente CHP-Phasen anhand pathologischer Porphyrinurien bei Familienangehörigen erkennen. Nach den vorliegenden Untersuchungen scheinen ca. 40% der „sporadischen“, also nicht-familiär auftretenden Fälle von CHP hereditär vorbedingt zu sein, wobei der UD-Defekt bei der hereditären Form außer in der Leber auch in nicht-hepatischen Zellen vorhanden ist. Eine Störung der hepatischen UD ist generelle Voraussetzung für die Entwicklung einer CHP. Für das Vorkommen einer nicht-hereditären, erworbenen, hepatotoxischen Form spricht, unabhängig von dieser Studie, die chemisch durch Hexachlorbenzol induzierbare CHP bei Mensch und Tier, die pathobiochemisch der nicht-hereditären CHP bei Alkohol-Leber-Syndromen analog ist. Bei 5–10% aller chronischen Leberkranken ist mit einer CHP zu rechnen. Mit Porphyrinbiochemogrammen im Urin werden nicht nur manifeste, sondern auch latente Formen der CHP am sichersten diagnostiziert.
    Notes: Summary Chronic hepatic porphyria (CHP), as a chronic hepatic disturbance of porphyrin metabolism, is regularly associated with chronic liver damage. It appears in latent and manifest stages and in the clinical manifestation leads to cutaneous symptoms: porphyria cutanea tarda. The primary enzymatic disturbance involves uroporphyrinogen decarboxylase (UD; EC 4.1.1.37). The enzyme was studied in 107 patients with “sporadic” CHP (29 women, 78 men) in red cells, and in 17 CHP patients (12 latent, 5 manifest) in liver biopsy tissue, too. The hepatic UD activity was diminished by 39–57% in all cases compared to controls (p〈0.001). The activity of red cell UD in 47 cases (44%) had decreased by 30 to 55% compared to the controls (p〈0.001). In this group, there were 70 patients (of which 30% women) with clinically manifest CHP, of which 43% (12 women, 18 men) presented a marked decrease in UD activity in erythrocytes, compared to the control group (n=96);p〈0.001). In patients with this enzyme level one supposes an inherited predisposition to be present which only becomes apparent with concommitant liver damage, alcohol and/or estrogens, leading to pathobiochemical and clinical-dermatological symptoms. Skin and liver findings are not different in both inherited and non-inherited forms of CHP. Family studies allow to detect, in hereditary CHP, an autosomal dominant genetical defect of the enzyme in erythrocytes, and to detect latent CHP phases in relatives on the base of pathological porphyrinurias. According to the studies made up to now, about 40% of „sporadic“, i.e. not family bound cases of CHP, seem to have inherited predisposition; the UD defect in the hereditary form is found not only in the liver but also in extra-hepatic cells. A disturbance of hepatic UD is a general premise for the development of a CHP. The occurrence of the non-inherited, acquired, hepatotoxic form is proved, apart from this study, by the inducibility of CHP in man and animals chemically by means of hexachlorobenzene. Pathobiochemically it is analogue to non-inherited CHP in alcohol liver syndromes. In 5 to 10% of all chronic liver patients one must reckon with a CHP. Porphyrin biochemograms of urine allow the safest diagnosis not only of manifest, but also of latent forms of CHP.
    Type of Medium: Electronic Resource
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  • 2
    ISSN: 1432-069X
    Keywords: Pityriasis rubra pilaris ; Histochemistry ; Autoradiography ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Five patients with pityriasis rubra pilaris (PRP) were analyzed by means of light and electron microscopy as well as by histochemistry and autoradiography. The results were compared with findings in psoriasis vulgaris. In PRP we found a moderate increase of the labeling index of epidermal cells, a highly increased labeling index of dermal infiltrating cells, and a mild spongiosis, and in the stratum granulosum, a decreased number of tonofilaments and an increased number of keratinosomes. The horny layer in PRP showed a pronounced histochemical and electron microscopical parakeratosis, even when histological parakeratosis was absent. In contrast with psoriasis vulgaris, there was no exocytosis of polymorphonuclear leucocytes into the epidermis, the papillomatosis index was normal, and there were no tortuous capillaries in the dermal papillae. The stratum granulosum was always present and sometimes thickened, showing electron microscopical changes different from those referred to in psoriasis. These changes point to a relatively distinct pattern of epidermal changes in PRP.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Archives of dermatological research 279 (1987), S. 173-179 
    ISSN: 1432-069X
    Keywords: UV-A pigmentation ; Ultrastructure ; Morphometry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary UV-A-induced skin pigmentation was investigated morphologically in semithin and thin sections from 11 volunteers, using different irradiation modalities (single doses of 10,50 and 100 J/cm2). Visible skin pigmentation was observed in all but two probands, and erythema in two; pronounced pigmentation was present after repeated irradiation only. Contralateral non-irradiated, UV-B-irradiated and suntanned skin specimens were used as controls. There was an increase in the number of clear cells in the basal layer (x 1.6) and particularly of large clear cells (x 1.7) after repeated irradiation. Also, the number of melanosomes in melanocytic dendrites (x 2.8) increased after repeated irradiation. The number, size and shape of the melanosome complexes in both basal and suprabasal keratinocytes remained unchanged, even when a distinction was made between central and peripheral location. In contrast, suntanned skin showed an increase in melanosome complexes in basal (x 5.8) and suprabasal (x 3.7) keratinocytes. It is concluded that UV-A-induced skin pigmentation differs in some ways from UV-B or sun-induced melanogenesis, and that the clinical grade of tanning cannot accurately be determined by ultrastructural methods.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Archives of dermatological research 279 (1987), S. 167-172 
    ISSN: 1432-069X
    Keywords: Morphometry ; Electron microscopy ; Cytological atypia ; Nevus cells ; Melanoma cells
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Cytological atypia, revealed in the course of routine light microscopy, is considered a valuable indicator of malignancy in melanocytic lesions. A clear definition of the term cytological atypia, however, is lacking. Therefore, by morphometric analysis of ultrathin sections of 11 malignant melanomas (7 invasive, 3 in situ, and 1 lentigo maligna melanoma) and 10 compound nevi, we evaluated the discriminating power of the various facets of cytological atypia, i. e., nuclear area, area of the nucleolus, area of the total cell, and nuclear irregularity. In each case, at least 50 intraepidermal melanocytic cells were examined. The two-sided U-test showed significant differences between intraepidermal nevus and melanoma cells, with regard to the mean values (x) and standard deviations (s) of the nuclear area (x and s, p=0.00011), area of the nucleolus (x, p=0.00043; s, p=0.00011), and area of the total cell (x, p=0.00011; s, p=0.00093). However, only the mean values and standard deviations of the nuclear area allowed a clear distinction in each individual case. The area of the nucleus can be estimated in the course of routine histology. We therefore think that the size and variation of the nuclear area should be considered in the histological differential diagnosis between malignant melanomas and benign nevi.
    Type of Medium: Electronic Resource
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