摘要:

We present a novel method for studying the changing characteristics of sebum excretion of facial skin over a 3-hour period. Sebum production can be quantified by analysis of the pore patterns formed on a sebum-sensitive tape (Sebutape®). We applied the CIE principles of reflectance colorimetry by measuring L*, a* and b* of Sebutapes every 15 min during 3 h of sebum collection. This combined technique yielded valuable new informations on the kinetics of sebum excretion, allowing the distinction between the follicular reservoir effect and the sebum flow

ISSN:0302-3427    

DOI:10.1159/000211083

出版商:S. Karger AG    

年代:1993

数据来源: Karger

摘要:

The binding of 5-methoxypsoralen (5-MOP) to human serum and blood fractions was studied by equilibrium dialysis associated to high-performance liquid chromatography. 5-MOP serum binding was 95% and kept constant in the range of therapeutic concentrations. Albumin was the main binding protein with one class of binding sites (n = 2.05) and with a moderate affinity constant (Ka = 10,270 M-1). Free fatty acids (FFA) enhanced 5-MOP binding to albumin. Binding to other proteins, α1-acid glycoprotein, gamma-globulins and lipoproteins (LDL, HDL, VLDL) also occurred, but was negligible. 5-MOP bound to red blood cells (RBCs) with a binding index (ratio of intra- to extra-globular 5-MOP concentrations) of 3.84 and 1.48 in buffer and plasma, respectively. 5-MOP distribution in blood was simulated. The free fraction of 5-MOP in blood could be increased in hypoalbuminemia, unchanged in acute inflammation, and decreased by FFA

ISSN:0302-3427    

DOI:10.1159/000211084

出版商:S. Karger AG    

年代:1993

数据来源: Karger

ISSN:0302-3427    

DOI:10.1159/000211085

出版商:S. Karger AG    

年代:1993

数据来源: Karger

摘要:

The activity of topically applied bifonazole was evaluated in vivo in the three androgen-dependent structures of the hamster flank organ, i.e. the pigmented spot, sebaceous glands and hairs. Topical bifonazole in our experience did not demonstrate any morphological effect on sebaceous gland and hair even when applied in the dosage of 3 mg/cm2/day. On the basis of our morphometric results we can conclude that topically applied bifonazole does not interfere with cutaneous androgen metabolic transformations in the pilosebaceous unit of the flank organ.

ISSN:0302-3427    

DOI:10.1159/000211086

出版商:S. Karger AG    

年代:1993

数据来源: Karger

摘要:

Topical retinoids have been employed in dermatology since the 1960s to treat a wide variety of cutaneous disorders. This review focuses on three areas in which retinoids have had their greatest impact: acne vulgaris, photoaging and cutaneous neo-plasia. The pharmacology of the available topical retinoids, their mechanism of action and the history of their use in these disorders are discussed.

ISSN:0302-3427    

DOI:10.1159/000211164

出版商:S. Karger AG    

年代:1993

数据来源: Karger

摘要:

The effects of some alkaloids and flavonoids, which are major ingredients in some of the Japanese Kampoh drugs (Japanese-Chinese traditional herbal medicines) experientially known to be efficacious for the treatment of acne vulgaris, on the lipogenesis in the sebaceous glands of the hamster ear, an excellent animal model for the human sebaceous gland, were studied. Lipogenesis was assayed by determining 14C incorporation into sebaceous lipids extracted from the sebaceous glands which were preincubated with 14C-acetate. We found that the lipogenesis in the hamster sebaceous glands was suppressed 63 and 54% by 10-4M berberine (an alkaloid) and wogonin (a flavonoid), respectively. We suggest that the therapeutic effects of some Japanese Kampoh drugs experientially used for acne vulgaris could be due to inhibition of lipogenesis by their active ingredients such as berberine and wogonin.

ISSN:0302-3427    

DOI:10.1159/000211087

出版商:S. Karger AG    

年代:1993

数据来源: Karger

摘要:

The aim of this preliminary report was to measure plasma and skin concentrations of Ro 15–0778 and its phenolic metabolite Ro 14–6113 in hairless rats receiving orally 10 mg/kg of Temarotene once daily during 10 days. Blood (2–3 ml) and skin (200–300 mg) samples were taken at different time points between 0.5 and 240 h after the last dose. We used a highly sensitive HPLC method for simultaneous determination of the two compounds with a quantification limit of 2 ng/ml in plasma and 10 ng/g in total skin (epidermis and dermis). After 10 h, plasma concentrations of Ro 14–6113 were 5–13 times higher than for Ro 15–0778. Ro 14–6113 concentrations in the skin were 4–10 times higher than for Ro 15–0778 within the initial 48 h. The concentrations of both compounds in the skin were higher than conce

ISSN:0302-3427    

DOI:10.1159/000211088

出版商:S. Karger AG    

年代:1993

数据来源: Karger

摘要:

Ascorbic acid has been shown to stimulate collagen synthesis in dermal fibroblasts by increasing the rate of transcription of collagen genes. Experiments involving the use of ascorbic acid require daily supplementation due to the instability of the molecule in aqueous solutions. In order to provide a more stable alternative to ascorbic acid, two salts of ascorbyl-2-phos-phate, having a greater chemical stability than ascorbic acid, were tested for their ability to stimulate collagen synthesis in monolayer fibroblast cultures. The concentration and time dependence of their activities were compared with ascorbic acid. The magnesium salt of ascorbyl-2-phosphate was found to be equivalent to ascorbic acid in stimulating collagen synthesis in these assays, while the sodium salt required at least a tenfold greater concentration to produce the same effect as ascorbic acid. Solutions of either ascorbic acid or the ascorbyl-2-phosphate analogs (at 10 mM) in phosphate-buffered saline (PBS) were relatively stable as shown by their decay rates and their ability to stimulate collagen synthesis even after nine days in solution prior to testing their effects on cultured cells. Ascorbic acid was unstable at neutral pH compared to solutions of either sodium or magnesium ascorbyl-2-phosphate. These data support the use of magnesium ascorbyl-2-phos-phate in experiments where stability of ascorbic acid is a concern, e.g. in long-term cultures or in in vivo studies.

ISSN:0302-3427    

DOI:10.1159/000211089

出版商:S. Karger AG    

年代:1993

数据来源: Karger

摘要:

Photoaging is primarily composed of wrinkling, mottled hy-perpigmentation and a tactile roughness of the skin, all three of these parameters improve following use of topical retinoids. It appears that smoothening of the skin results from a combination of epidermal changes including thickening, stratum corneum compaction and glycosaminoglycan deposition. Lightening of actinic lentigines and mottled hyperpigmenta-tion correlates with a reduction in epidermal melanin content maybe resulting from inhibition of tyrosinase activity. Effacement of wrinkling in mice correlates with new collagen synthesis, and there is evidence that this is also the case in humans. An irritant dermatitis is a feature of retinoid-treated skin but this diminishes in severity during treatment despite continued improvement in photoaging. Thus it is unlikely that irritation per se is responsible for clinical improvement.

ISSN:0302-3427    

DOI:10.1159/000211166

出版商:S. Karger AG    

年代:1993

数据来源: Karger

摘要:

The report differentiates between dermatological and transdermal products, identifies and discusses the principles involved in the development and optimization of topical drug products. The regulatory concerns in the evaluation of topical dermatological products with respect to bioequivalence and quality control are also discussed.

ISSN:0302-3427    

DOI:10.1159/000211090

出版商:S. Karger AG    

年代:1993

数据来源: Karger