PubMed Health⌕ Search

Biomedical subjects

H Schell

Publications and source records attributed to H Schell.

At least 73 records · Page 4Linked to original sources
PubMed1987

Cell kinetics of the human anagen hair follicle. Flow cytometric studies in healthy and psoriatic subjects.

Anagen hair follicles obtained from both healthy (n = 7) and uninvolved psoriatic (n = 4) scalps were segmentally analyzed for proliferative activity using DNA flow cytometry. Hair follicle kinetics were almost equal in either group except for the infundibular portion which exhibited significant increase of S-phase values in psoriatic patients. Maximum proliferation was disclosed within the bulbar segment. This study confirms that cell kinetics behavior of hair follicles from uninvolved scalp of psoriatics compared with those from healthy scalps is altered in the infundibular portion only.

Adult↗
PubMed1986

[Fulminant acne: therapy with 13-cis-retinoic acid and indomethacin].

Young men with mild acne vulgaris may rarely experience a very acute exacerbation with ulceration and necrosis of the lesions accompanied by fever, malaise, loss of weight, often by polyarthritis, and occasionally by erythema nodosum. Elevated sedimentation rate and marked leucocytosis are characteristic; microhematuria is often observed. This condition has been called acne fulminans. We report on a young male patient suffering from severe acne fulminans. Systemic 13-cis retinoic acid (Roaccutan, Accutane) and indomethacine (Amuno) treatment rapidly improved the skin and joint lesions. Intracutaneous tests with viral, bacterial, and fungal antigens before and during treatment suggest a temporary cellular immune defect.

Acne Vulgaris↗
PubMed1986

[Cell kinetics of human scalp hair--impulse cytophotometric studies].

DNA Flow Cytometric measurements (DNA-FCM) were performed on both anagen hair bulbs of 21 healthy volunteers (11 females, 10 males; aged between 18 and 21 years) and tufts of plucked hairs from 43 test persons (17 showing normal trichograms, 12 with telogen and 14 with dystrophic hair root pattern; aged between 19 and 49), subsequently submitted to routine trichogram investigation. The high proliferative activity of anagen hair bulb cells was accurately registered by FCM. Neither sex nor hair color nor hair length were found to influence the proliferative parameters. The degree of hair loss-as diagnosed on account of the trichogram-was also reflected by the DNA histograms; telogen and dystrophic hair root patterns, however, could not be discerned by FCM.

Adolescent↗
PubMed1986

Comparative morphological and growth kinetics studies of human hair bulb papilla cells and root sheath fibroblasts in vitro.

Dermal papillae isolated from anagen hair bulbs obtained from biopsy specimens from five subjects with normal hair pattern, and fibroblasts derived from the mesenchymal root sheaths (RSF) of the same hair follicles were separately grown in culture and the cell-cycle distribution pattern on different days was analyzed by applying DNA flow cytometry (FCM). Papilla cells (PC) exhibited distinctive morphological features by forming cell aggregates differing from RSF with respect to cell shape and growth pattern. They also proliferated remarkably more slowly than RSF. DNA-FCM analysis showed that both PC and RSF demonstrated synchronous fluctuations in the percentage of cells in G1/0, S and G2 + M phases during the period of subculture.

Adult↗
PubMed1986

Papillomavirus DNA in warts of immunosuppressed renal allograft recipients.

Renal allograft recipients were shown to have an increased incidence of warts and skin cancers. We examined 148 patients for evidence of wart virus infections and tested for papillomavirus types, which are known to be associated with human malignancies. Of the 148, 36 (24.3%) patients were afflicted with warts at the end of our study period, in contrast to 5 of 148 (3.3%) before transplantation. DNA from 16 different biopsies was extracted by phenol treatment for further virological studies. DNA of human papillomavirus (HPV) 2 was detected three times, DNA of HPV 4 and 10 twice, and DNA of HPV 3 and 16 once each by blot hybridization. One probe led to strong signals with HPV types previously found only in epidermodysplasia verruciformis patients. A correlation between histology and virus type existed in cases of HPV 2, 3, 4, and 10 infections.

Adolescent↗
PubMed1986

[Tricholemmal carcinoma. Report of 11 cases].

Eleven cases of tricholemmal carcinoma are reported. The histological features of tricholemmal carcinoma are compared with those of tricholemmoma. The tumor is very rare and occurs in slightly damaged skin of elderly people. Whereas its clinical appearance is nonspecific, it can be differentiated from tricholemmoma by the occurrence of marked cellular and nuclear atypia and less orderly architecture. Although the histological picture suggests a high-grade malignancy, its biological behaviour appears to be relatively benign. To date, no metastases have been observed in our patients.

Aged↗
PubMed1985

[Hydroa vacciniforme--urocanic acid content of the horny layer of the epidermis].

Urocanic acid was measured by means of high-performance liquid chromatography (HPLC) in the stratum corneum of a 3.5-year-old child suffering from hidroa vacciniformia. Compared to ten healthy children of equal age, the urocanic acid content of the stratum corneum was reduced significantly. In addition, there was an elevated level of some amino acids in the urine, particularly that of histidine and methylhistidine, which seems to be a very important finding. Urocanic acid acts as a natural sun protective agent, and the results are discussed with this in mind. It was not possible to elicit hidroa vacciniformia lesions in the patient by UV-A, as described by others.

Amino Acids↗
PubMed1984

13-cis-retinoic acid in conglobate acne. A follow-up study of 14 trial centers.

A follow-up was done on the patients of the German multicenter study with severe conglobate acne who had been treated with different dosages of 13-cis-retinoic acid. Eighty-seven patients were monitored from 12 to 21 months. Optimal long-term therapeutic effects were obtained with an initial dose of 1.0 mg/kg body weight, for 3 months, followed by another 3-month-treatment period with 0.2 mg/kg body weight. Six months after the termination of therapy 96% of the patients were still in remission and 81% after 12 months. Comparative figures for the administration of doses were 84% as opposed to 47% (0.5----0.2 mg/kg body wt.) and 74% as opposed to 37% (0.2----0.2 mg/kg body wt.), respectively. It is suggested from the present data that a high initial dosage of 13-cis-retinoic acid be chosen in order to obtain optimal long-term therapeutic effects. Transiently elevated lipid levels as well as other tolerable side effects return to normal within 3 months at the latest after discontinuation of treatment.

Acne Vulgaris↗
PubMed1984

Cyclic nucleotides in human epidermis--diurnal variations.

In 12 healthy, adult males, the epidermal content of both cAMP and cGMP was determined radioimmunologically every 6 h over a period of 30 h, avoiding any ischemia, which can alter unphysiologically the in vivo levels of epidermal cyclic nucleotides. For cAMP a diurnal fluctuation with maximal level at midnight could be proved (p less than 0.05), whereas cGMP, in contrast to experiments in mice, revealed no significant variation during the test period. The presented results describe for the first time the diurnal course of human epidermal cGMP.

Adult↗
PubMed1983

Epithelial cell proliferation of oral lichen planus in patients treated with an aromatic retinoid.

In 4 patients with lichen planus mucosae (l.p.m.) biopsies were taken from the involved and uninvolved buccal sides before treatment and from the affected side after a 3-week systemic therapy with aromatic retinoid (Ro 10-9359; 50 mg/die). After in vitro labelling with 3H-thymidine the epithelial cell proliferation was determined histo-autoradiographically. In atrophic lesions of l.p.m., increased 3H-thymidine labelling indices were observed during retinoid therapy. After 3 weeks of treatment the augmented relative portion of labelled basal cells (quotient LIbas/LIsuprabas) was found to be lowered, indicating a tendency of proliferating cells to regain normal distribution in the progenitor compartment of the mucosa epithelium.

Adult↗
PubMed1981

[Sites of predilection of leukoplakia and carcinoma of the oral mucosa (author's transl)].

In a prospective study, begun in 1976, of so far 248 patients with histologically confirmed oral leukoplakia there have been 48 (27 males, 21 females) with precancerous lesions and 25 (22 males, 3 females) with carcinoma. While half of the benign leukoplakias were in the buccal region, precancerous lesions and carcinoma dominated with increasing frequency in the lower half of the oral cavity. Among the precancerous mucosal lesions 23% were in the lateral or ventral region of the tongue, 10% in the sublingual region. Among the carcinomas nearly 10% were at the back of the tongue, 29% in the lateral or ventral region of the tongue, and 23% in the floor of the mouth. Of 22 proven leukoplakias in the sublingual region 20 were either precancerous or carcinoma. In order to improve the early recognition of oral precancerous or cancerous lesions it is essential to include the lower regions in any examination of the oral cavity.

Adolescent↗