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Biomedical subjects

H Schell

Publications and source records attributed to H Schell.

At least 55 records · Page 3Linked to original sources
PubMed1990

[Endocrinologic diagnosis in hirsutism and androgenetic alopecia in women].

In women, hirsutism and male pattern baldness are due to an enhanced effect of androgens on the hair follicle, which in turn can be caused by an increased supply of bio-available androgens and/or an increased sensitivity of the target organ to androgens. There are no definite correlations between circulating androgens and the degree of their biological effects. Although in most cases the hyperandrogenemia is not severe, the patients should be treated with antiandrogens in order to avoid progression of the disturbance and its consequences on metabolism and fertility. Sometimes hirsutism can be observed as a clinical sign of a defect in the steroid biosynthesis or of Cushing's syndrome. In severe hyperandrogenemia with a testosterone level of more than 2 ng/ml and a DHEA-S level of more than 8000 ng/ml, tumors of the ovaries or the adrenal glands have to be excluded.

Androgens↗
PubMed1990

[Proliferation behavior of the anagen hair bulb in androgenetic alopecia before and after local administration of 17 alpha- propylmesterolone--DNA flow cytophotometry studies].

10 male test persons with androgenetic alopecia (Hamilton stage IV) were topically treated with an alcoholic 17 alpha-propylmesterolone solution (PM, 3%) for 3 months. Before and after treatment, we took deep biopsies from the fronto-temporal scalp region. Microsurgically, we isolated anagen hair bulbs, connective tissue with epidermis, and fat from the biopsy samples in order to determine cell cycle kinetics by means of DNA-flow cytometry. By comparison, cell cycle kinetics of the pre- and post-treatment samples did not show any significant changes with regard to connective tissue and fat, whereas in anagen hair bulbs, we found a significant increase of both S-phase cells (%) and the proliferation index (%). These results imply that PM, if topically applied, enhances the proliferative activity of hair matrix cells.

Administration, Topical↗
PubMed1990

[Proliferation kinetics of human anagen hair in hyper- and hypothyroidism: DNA flow cytometry studies].

Disorders of the thyroid function and abnormalities of the scalp hair growth are frequently associated. Former studies were based on clinical findings and trichorhizogram evaluation. Our present study making use of DNA-flow cytometry demonstrates the influence of thyroid hormones on the proliferative activity of anagen hair bulbs in patients suffering from disorders of the thyroid function. In comparison with a healthy control group (n = 20), the mean proliferative activity (S- and G2+M-%) was found 15% lower in hypothyroid patients (n = 6), whereas in hyperthyroidism (n = 6) we observed an increase of the corresponding values of about 30%. Our data might suggest a direct correlation between S-phase percentages and plasma T3 levels, but this assumption could not be proved by statistical methods.

Adult↗
PubMed1990

[Internal and external therapy with corticoids].

The toxicological, pharmacological, and clinical properties of corticoids are well understood. As their main actions are based on an uniform mechanism, it is impossible to separate beneficial effects from side effects. Therefore, any augmentation of the therapeutic activity is associated with an increased risk of side effects in systemic as well as in topical use. The topical application of highly potent corticoids also bears the risk of systemic side effects, especially those with prolonged activity. In addition, it has to be kept in mind that apart from the skin, the functions of various organs can be unfavorably affected when corticoids are systemically applied.

Administration, Oral↗
PubMed1990

Flow cytometric analysis of cell cycle kinetics of anagen scalp hair correlated with plasma androgens in hirsutism.

Cell kinetics of anagen scalp hair bulbs obtained from hirsute (n = 13) as well as healthy (n = 10) females were analysed by DNA-flow cytometry. The cell cycle kinetics in hirsutism revealed a significant increase of S-phase cells (10.2%) and a significant decrease of G0/1-phase cells (80.7%) compared with healthy females (S-phase 7.5%, G0/1 phase 86%). Moreover, dehydroepiandrosterone sulfate (DHEA-S) levels and cell cycle kinetics obtained from the hirsute females yielded a strong correlation between the height of S-phase percentages and DHEA-S values, whereas no correlation could be proved between testosterone levels and DNA-FCM data. Therefore, the weak androgen DHEA-S is assumed to be one hormonal factor influencing the cellular growth kinetics of hair bulbs in androgen-sensitive scalp areas.

Adult↗
PubMed1990

[Value of high resolution ultrasound in determination of vertical tumor thickness in malignant melanoma of the skin].

The maximal thickness of a primary malignant melanoma of the skin can be determined preoperatively by means of modern high-frequency ultrasound scanners (20 MHz). In this way operative therapy can be planned and the minimal excision margins can be determined before surgery. The present study demonstrates a strong correlation (r = 0.97) between preoperative ultrasound and postoperative histometric determination of tumour thickness in 72 primary malignant melanomas. The study showed, however, that ultrasound scanners cannot distinguish unequivocally between histologically confirmed tumour cell aggregates and subtumoral remnants of a benign melanocytic naevus or subtumoral lymphocytic infiltrates. In these cases, determination of tumour thickness by ultrasound yields higher values for thickness than do histological examinations. In addition, tumour cell aggregates that are smaller than the lower limit of scanner resolution, are very close to the main tumour mass, or have infiltrated the deeper dermis cannot be measured accurately. In these cases, ultrasound examination underestimates the tumour thickness.

Humans↗
PubMed1989

Influence of topically applied betamethasone-17-valerate on cell cycle kinetics of human anagen hair determined by DNA flow cytometry.

In 47 healthy volunteers betamethasone-17-valerate (0.1% solution and cream) was topically applied twice daily on the scalp skin. After 7 and 14 days treatment, anagen hairs were plucked in each volunteer from both treated and untreated contralateral scalp areas. Cell cycle analysis of plucked anagen hairs was performed by means of DNA flow cytometry. Already after topical betamethasone-17-valerate application for 7 days, cell kinetic changes were found showing a slightly significant decrease of S and G2 + M cell percentages and a significant increase of G0/1 cell percentages. The present study demonstrates the possibilities of DNA flow cytometry to study the pharmacological effects on cell kinetics of plucked human anagen hairs.

Administration, Topical↗
PubMed1988

[DNA impulse cytophotometric studies of the modification of the proliferation behavior of the outer hair root sheath by topical glucocorticoid administration].

A corticoid preparation (C) was topically applied on the scalps of 47 healthy test persons for 7 or 14 days, resp. After this treatment, we plucked anagen hairs under standardized conditions both from the area treated with C and the contralateral, untreated area. The proliferative activity of plucked anagen hairs with root sheaths was analyzed by means of DNA flow cytometry. Already a 7 days treatment with topical C resulted in kinetic changes of the outer root sheath: The percentage of the cells in the G1/10-phase of the cell cycle was increased, whereas that of the cells in the S-phase and the G2+M-phase was decreased.

Betamethasone↗
PubMed1988

Collagen-type synthesis in human-hair papilla cells in culture.

Hair-papilla derived cells were grown in monolayer culture and revealed the typical morphology and growth pattern which was similar but not identical to control fibroblasts. Hair-papilla cells were found to produce considerable amounts of collagen type I and type III and fibronectin. Type IV collagen production could not be detected. The ratio of collagen type III and type I clearly differed from the pattern observed in normal fibroblasts, being much higher in hair-papilla cells, where type III accounted for more than 20% of total collagen synthesis. These data show that hair-papilla derived cells have biosynthetic capacities similar to those of human skin fibroblasts as well as characteristic differences, indicating that they represent a specialized fibroblast subpopulation.

Adult↗
PubMed1988

Modified syntheses of dopamine-4-sulfate, epinephrine-3-sulfate, and norepinephrine-3-sulfate: determination of the position of the sulfate group by 1H-NMR spectroscopy.

With respect to the growing interest in sulfoconjugated catecholamines (CAS), reliable syntheses of those substances including high purification and unequivocal identification are required. For the syntheses of the 3-O-sulfates of norepinephrine (NE) and epinephrine (EPI), modifications of the methods of Stolz (12) and Arakawa et al. (1) were performed. Noradrenalone and adrenalone were prepared according to the method of Stolz (12) and sulfated by reaction with pyridine-sulfurtrioxide complex in dry pyridine at 60 degrees C. After reduction of these ketosulfates by sodium borohydride in dry pyridine, NE-3-O-S and EPI-3-O-S were obtained respectively. We synthesized dopamine-4-O-sulfate (DA-4-O-S) by reaction of DA hydrochloride with pyridine-sulfurtrioxide complex in dry dimethylformamide at 20 degrees C (Harbeson et al., 1983). The highly purified products (DA-4-O-S, NE-3-O-S, EPI-3-O-S) were characterized by their melting points (mp), infrared spectra (IR), thin-layer chromatography (TLC), high-performance liquid chromatography (HPLC), elemental analysis, and 1H-nuclear magnetic resonance spectroscopy (1H-NMR).

Dopamine↗
PubMed1987

[Treatment of rosacea with isotretinoin. Results of a multicenter trial follow-up].

A follow up investigation was done on forty-seven patients of the German multicenter study with severe and long standing rosacea who had been treated with isotretinoin (0.5 mg/kg bw/day) over twelve or twenty weeks. During the post-treatment follow up which lasted an average of fifty-seven weeks, seven relapses were registered whereas forty patients remained in remission. After drug withdrawal, both the percentage of patients without inflammatory lesions (pustules, papules or nodules) as well as the mean values of inflammatory lesions remained almost constant over the whole observation period.

Clinical Trials as Topic↗
PubMed1987

[Site-specific incidence of benign and precancerous leukoplakias and cancers of the oral cavity].

The distribution patterns of benign and precancerous oral leukoplakias as well as oral cancer were investigated in 547 patients. The most frequently affected site was the buccal mucosa, the rarest localization was the floor of mouth. 96% of buccal lesions were benign, 4% were precancerous or cancerous. In contrast, 68% of the lesions on the floor of the mouth were precancerous or cancerous. Our results indicate, that the localization of leukoplacic lesions in the oral cavity is an important hallmark of their dignity.

Adolescent↗
PubMed1987

Effects of epidermal growth factor, fibroblast growth factor, minoxidil and hydrocortisone on growth kinetics in human hair bulb papilla cells and root sheath fibroblasts cultured in vitro.

Comparative studies on growth kinetics of cultivated human hair bulb papilla cells (PCs) and hair root sheath fibroblasts (RSFs) yielded evidence of some peculiarities of PCs in both proliferative behavior and morphological growth pattern. As the dermal papilla, essentially supporting the nutrition of matrix epithelium, can be considered a target tissue for agents influencing maintenance of hair growth, we studied the effects of epidermal growth factor (EGF), fibroblast growth factor (FGF), minoxidil (Mino), and hydrocortisone (HC) on the proliferation of PCs and RSFs, both gained from dissected hair follicles of scalp biopsy specimens of two male adults and separately cultured in vitro. EGF and FGF proved to increase proliferation of both PCs and RSFs most, yet at a different intensity for each cell group. HC slowed proliferation, and Mino failed to influence growth of PCs and RSFs.

Adult↗
PubMed1987

Morphological and flow-cytometric characterization of a trichilemmoid carcinoma cell line in vitro.

A cell line derived from a trichilemmoid carcinoma of a 85-year-old male was established in vitro and maintained in culture for 14 months. From the explant culture to the second passage, the tumour cells propagated slowly. After 6 months (third passage) faster growth behaviour was noticed. In culture the neoplastic cells continued synthesizing abundant glycogen. The DNA histogram of original neoplastic cells revealed a seemingly normal unimodal DNA distribution. The tumour DNA remained apparently stable during the subsequent months in culture. However, after 6 months in culture, flow cytometry disclosed a spontaneous shift in nuclear DNA content. This study enabled us to establish in vitro the malignant properties of the tumour and strongly suggested that it was derived from trichilemmal cells.

Aged↗