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PubMed1991

Hair cosmetics.

Alterations in the cuticle, cortex, and medulla are necessary to modify the hair cosmetically. The hair can be modified externally by the use of shampoos to remove excess sebum, conditioners to restore shine, and styling aids to increase manageability. Several different formulations of all these products exist, depending on the needs of the patient. Furthermore, the hair can be modified both externally and internally through the use of hair dyes, permanent waving lotions, and hair straighteners. Use of these products causes external damage to the hair shaft by disrupting the overlapping cuticular scales, rendering the hair susceptible to static electricity and the effects of humidity while decreasing manageability and shine. Internal damage created by these products decreases the hair shaft's elastic properties, allowing increased hair breakage. The dermatologist can better aid the patient with hair difficulties if he or she has an understanding of the formulation and effects of products designed to cleanse, beautify, and modify the hair.

Cosmetics↗
PubMed1990

[Evaluation of the anti-comedo effect of azelaic acid using the technique of horny layer biopsy and scanning electron microscopy].

Hyperkeratosis of the follicular channel is the most common finding in acne skin. The hyperkeratosis may represent an altercated keratinization process or the consequence of the abnormal sebum production and excretion. Several review demonstrated the anti-comedo activity of azelaic acid in acneic skin. This action may be due either to an anti-hormonal effect or to a change in keratin production. The aim of this work is to investigate the anti-comedo activity of 20% azelaic acid cream topically applied in a group of teen-agers affected by acne. A horny layer biopsy with cyanoacrylate glue was performed before and after four months of treatment with azelaic acid cream in ten acne patients. About 1 cm square horny layer biopsy was metallized and observed at the scanning electron microscopy to count the number of comedos. With this method we detected a reduction of about 26% of the comedos after four months of azelaic acid treatment. The result we obtained is in accordance with previous works about the anti-comedo activity of azelaic acid.

Acne Vulgaris↗
PubMed1990

Factors predisposing to cutaneous irritation.

In experimental skin toxicology, as well as in clinical practice, considerable interindividual variation in the susceptibility to irritant dermatitis is noted when irritant doses are low. Cutaneous sensitivity and hypersensitivity are not determined by a single known feature but are multifactorial. Previous atopic dermatitis may predispose to irritant dermatitis. Susceptibility to irritation seems to be influenced by age, race, and genetic background, whereas sex-related differences do not seem to exist. Of biophysical skin baseline features, skin-surface pH was correlated with the severity of experimentally induced irritant dermatitis, but baseline transepidermal water loss, water-holding capacity, stratum corneum turnover time, and sebum content were not.

Age Factors↗
PubMed1987

Omphalokeratolith.

A 69-year-old woman presented with a firm, black umbilical mass of unknown duration. It was easily removed with a warmed otic glycerin preparation. Histologic examination showed that it contained laminated keratin, amorphous material resembling sebum, numerous terminal hairs, and scattered collections of bacteria. Moderate amounts of argentaffin staining material were detected throughout the specimen, and the black color of the lesion was probably due to melanin and oxidized lipids, much like an open comedone. The mass is appropriately called an omphalokeratolith.

Aged↗
PubMed1988

Spironolactone and cimetidine in treatment of acne.

In an open therapeutic trial, 50 patients with acne vulgaris were randomly allocated to one of two groups. One group received spironolactone 100 mg daily and the other cimetidine 1.6 g daily for 12 weeks. Clinical severity of acne and sebum excretion decreased significantly at the end of the trial with both drugs, but significantly more with spironolactone. Mean serum levels of testosterone, androstenedione and dehydroepiandrosterone-sulfate decreased significantly with spironolactone but showed no change with cimetidine. Our data suggest that spironolactone may be useful as antiandrogen in the short term therapy of acne vulgaris.

Acne Vulgaris↗
PubMed1989

[Current therapy of acne vulgaris].

The treatment of acne vulgaris depends on its causes. The focal point of its etiopathogenesis is the raised sebum production, but a major part is also played by the proliferative and retentive hyperkeratosis in the infra-infundibulum and the proliferation of acne bacteria. Since the clinical syndrome of acne consists of many factors, combined treatment is always required. Besides from treating the seborrhoea, the hyperkeratosis and the inflammatory alterations, it is very important to provide psychological guidance for the patient. We discuss the individual active substances and explain their application and side effects. Thanks to the new powerful active substances which have been available in the last few years to the therapist, he is in a position of successfully treating over 90% of patients suffering from acne thanks to individually adapted and differentiated treatment; but this also forces him to assimilate his knowledge continuously to the newest standard.

Acne Vulgaris↗
PubMed1989

Acne vulgaris.

Acne vulgaris is a disease of the pilosebaceous unit that affects nearly all persons to some degree during the teenage years. It is a disease that should be treated because of the anxiety and disfigurement it causes in the affected patient. Acne therapy is directed against the three probable pathogenic processes in acne: (1) abnormal keratinization of the sebaceous follicle, (2) excessive production of sebum, and (3) proliferation of bacteria in the follicle. Superficial acne consisting of comedones and small papulopustules will frequently respond to topical therapy such as retinoic acid, benzoyl peroxide, and topical antibiotics. Deeper lesions require systemic antibiotics of which tetracycline is the drug of choice. Severe, recalcitrant cystic acne usually responds well to the oral retinoid, isotretinoin. The severe teratogenic effects of isotretinoin on a developing fetus make this a risky drug to prescribe for women with childbearing potential. In such cases the greatest precautions should be taken to avoid pregnancy during a course of isotretinoin. Such precautions include pregnancy testing, contraceptive counseling, and the use of at least two effective forms of birth control in sexually active women.

Acne Vulgaris↗
PubMed1979

Structure of the sheep epidermis.

The stratum corneum measured on fresh frozen sections was found to be considerably thicker than previously reported. It was uniformly permeated with sebum, which also formed an intact film over the skin surface and it could readily be divided into two zones. The living epidermis was approximately half as thick as the stratum corneum.

Animals↗
PubMed1979

The effects of some surface sampling procedures on the stratum corneum of bovine skin.

Clipping and shaving remove cell and lipid layers from the stratum corneum and also modify the effects of subsequent lipid collection and microbiological sampling techniques. The damage to the epidermis caused by solvents indicates that further evaluation of some sebum collection procedures and of the effects of dips and dressings applied to the skin is required.

Animals↗
PubMed1989

[Aspects of tolerance to transdermal systems from the dermatologic viewpoint].

If active drugs are required to penetrate the skin in order to reach the systemic circulation the integrity of the skin has to be impaired. The nature of the horny layer which, as the uppermost barrier takes over the main part of the protective function of the skin against all locally applied substances, is shortly outlined. It is demonstrated that inactive ingredients of transdermal therapeutic systems should induce only the minimum irritation of the horny layer which is absolutely necessary for the action of the system. A good tolerance seems to be granted only if an occlusion at all events is of a short duration, and the sebum deficiency and the vulnerability of the aging skin as well as the xerosia and residual syndets in the horny layer after frequent washing, baths or showers are taken into account. Furthermore, the potential risk for skin sensitization is discussed as each patch application can primarily induce a sensitizing potential for the applied active or inactive ingredient, which possibly may cause a contact eczema on repeated therapy. However, only a wide application and unfortunately not the clinical trial will supply detailed information on this aspect of risk.

Administration, Cutaneous↗
PubMed1989

Physiological consequences of human skin aging.

The expression and treatment of cutaneous disease in the elderly differ from those applicable to younger adults. Anatomical changes in aging skin result in altered physiological behavior and susceptibility to disease. Decreased epidermal renewal and tissue repair accompany the aging process. The rate of hair and nail growth declines, as well as the quantity of eccrine, apocrine, and sebum secretion. There are alterations in immune surveillance and antigen presentation with aging. The cutaneous vascular supply is decreased, leading to decreases in inflammatory response, absorption, and cutaneous clearance. Impaired thermal regulation, tactile sensitivity, and pain perception occur as one ages. We summarize the major changes that occur during the intrinsic aging process of the skin to facilitate the recognition and treatment of skin disease in the older patient.

Adult↗
PubMed1989

[Immunohistochemical study on the mechanism of excretion of methamphetamine].

Many methods of analysis are available to the forensic toxicologist for determining the amount of methamphetamine within human tissues, but few have the potential of histochemistry for enabling the precise site of excretion of methamphetamine to be defined. We have established a method for the demonstration of methamphetamine by immunohistochemistry, and applied this method for showing morphologically the disposition of methamphetamine. The following cells in the tissues of methamphetamine-intoxicated mice gave a strong positive reaction of the localization, which was thought to be the histological evidence of excretion of this drug: epithelial cells of the distal part of the renal tubule and of the collecting tubule, transitional epithelial cells of the bladder, liver parenchymal cells, epithelial cells of the striated duct of the salivary gland, parietal cells of the gastric gland, part of epithelial cells of the distal portion of the large intestine, secretory cells and part of epithelial cells of the ductal portion of the sweat gland, alveolar cells of the mammary gland, secretory cells of the sebaceous gland and hair medulla and cortex. These results indicated passive diffusion of methamphetamine across membranes of the cells of the distal tubule and collecting tubule of the kidney, of the bladder and of the striated duct of the salivary gland. In the parietal cells of the gastric gland, part of epithelial cells of the distal portion of the large intestine and secretory cells of the sweat gland, methamphetamine was thought to be stored and subsequently released. In the mammary gland, methamphetamine was found to be combined with casein and excreted by exocytosis. Accumulation of methamphetamine in the hair was supposed to be chiefly due to the penetration of this drug derived from tissue fluid and sebum.

Animals↗
PubMed1987

[Anti-seborrhea effect of cimetidine].

Cimetidine, a histamine H2 antagonist, seems to have anti-androgenic activity. 22 young women were studied during follicular phase prior to and after a 3 month period of treatment with cimetidine (1,200 mg daily). Three month treatment with cimetidine resulted in a significant decrease of seborrheic index (p less than 10(-4)) and casual level (p less than 10(-4)). Testosterone level, TeBG binding capacity and free testosterone were unaffected by the treatment. Cimetidine decrease sebum secretion without change in androgen parameters.

Acne Vulgaris↗
PubMed1988

[Microbial flora and odor of the healthy human skin].

The microflora resident on human skin shows great interindividual and intraindividual differences. It is essentially composed of micrococci, staphylococci, aerobic and anaerobic coryneforms as well as pityrosporum species which, in accordance with the different environment in the different regions of the body, are in a steady state. With increasing age, human skin microflora undergoes qualitative changes: the streptococci, which are found in infants, disappear and coryneform bacteria occur, which are mainly responsible for odor production. Anaerobic propionibacteria are more numerous in juveniles and young adults, a fact that may be explained by increased sebum production. Only the coryneform bacteria are able to produce the typical axillary odor by decomposition of apocrine sweat. Cocci, however, obviously do not have this capacity. It remains to be established which substances participate in odor production. With sensitive chromatographic methods amino acids, steroids and free fatty acids were detected, which could be related to body odor. There are possibly only a few commonly occurring odorous substances. The necessity of analyzing these substances is stressed.

Amino Acids↗
PubMed1985

[Roaccutan in acne and rosacea].

Isotretinoin (Accutane) is a lately developed synthetic oral retinoid for treatment of severe forms of cystic acne resistant to therapy. Its pharmacological effect principally consists in decreased size of the sebaceous glands, reduced sebum production, as well as alteration of the bacterial micropopulation. At a dosage of 0.5 mg up to 1.0 mg/kg body weight daily, isotretinoin led to significant reduction of the inflammatory skin eruptions and long-lasting remission after discontinuation of the drug. With regard to 18 patients suffering from rosacea, the application of Accutane brought about satisfactory results, as well. Mucocutaneous side-effects were almost compulsory, but did never lead to discontinuation of the treatment. Because of its teratogenity, isotretinoin must not be applied in case of gravidity. Accutane offers new modes of therapy with respect to patients suffering from nodulocystic acne or severe rosacea which did not respond to common forms of treatment.

Acne Vulgaris↗
PubMed1988

Fatty acids of pulmonary surfactant phosphatidylcholine from fetal rabbit lung tissue in culture. Biosynthesis of n-10 monoenoic fatty acids.

We have previously reported that fetal rabbit lung tissue in organ culture produces a lamellar body material (pulmonary surfactant) with a lower percentage of disaturated phosphatidylcholine than is typically found in rabbit lung in vivo (Longmuir, K.J., C. Resele-Tiden, and L. Sykes. 1985. Biochim. Biophys. Acta. 833: 135-143). This investigation was conducted to identify all fatty acids present in the lamellar body phosphatidylcholine, and to determine whether the low level of disaturated phosphatidylcholine is due to excessive unsaturated fatty acid at position sn-1, sn-2, or both. Fetal rabbit lung tissue, 23 days gestation, was maintained in culture for 7 days in defined (serum-free) medium. Phospholipids were labeled in culture with [1-14C]acetate or [U-14C]glycerol (to follow de novo fatty acid biosynthesis), or with [1-14C]palmitic acid (to follow incorporation of exogenously supplied fatty acid). Radiolabeled fatty acid methyl esters obtained from lamellar body phosphatidylcholine were first separated by reverse-phase thin-layer chromatography (TLC) into two fractions of 1) 14:0 + 16:1 and 2) 16:0 + 18:1. Complete separation of the individual saturated and monoenoic fatty acids was achieved by silver nitrate TLC of the two fractions. Monoenoic fatty acid double bond position was determined by permanganate-periodate oxidation followed by HPLC of the carboxylic acid phenacyl esters. Lamellar body phosphatidylcholine contained four monoenoic fatty acids: 1) palmitoleic acid, 16:1 cis-9; 2) oleic acid, 18:1 cis-9; 3) cis-vaccenic acid, 18:1 cis-11; and 4) 6-hexadecenoic acid, 16:1 cis-6. In addition, 8-octadecenoic acid, 18:1 cis-8, was found in the fatty acids of the tissue homogenate. The abnormally low disaturated phosphatidylcholine content in lamellar body material was the result of abnormally high levels of monoenoic fatty acid (principally 16:1 cis-9) found at position sn-2. Position sn-1 contained normal levels of saturated fatty acid. The biosynthesis of the unusual n-10 fatty acids was observed from the start of culture throughout the entire 7-day culture period, and was observed in incubations of tissue slices of day 23 fetal rabbit lung. This is the first report of the biosynthesis of n-10 fatty acids (16:1 cis-6 and 18:1 cis-8) in a mammalian tissue other than skin, where these fatty acids are found in the secretory product (sebum) of sebaceous glands.

Animals↗
PubMed1988

In vitro and in vivo antistaphylococcal activity of human stratum corneum lipids.

Despite the assumption that sebum-derived fatty acids are responsible for cutaneous antimicrobial defense, no studies have assessed the contribution of epidermis-derived lipids. Herein, we tested the antistaphylococcal effects of human stratum corneum lipids, enriched in endogenous, keratinocyte-derived species obtained by lipid extraction and thin-layer chromatography, for antimicrobial activity in both in vitro and in vivo systems. Whereas the most potent species in vitro were the free fatty acids, polar lipids and glycosphingolipids also demonstrated antistaphylococcal activity in vitro, while other neutral lipids displayed virtually none, results that were confirmed with authentic standards in vitro. In a pilot study on delipidized forearm test sites in human volunteers, naturally occurring free fatty acids, polar lipids, and glycosphingolipids exhibited significantly more antistaphylococcal activity than other stratum corneum lipids or vehicle controls. Finally, biopsy specimens of incubated skin sites demonstrated penetration of staphylococci through lipid-enriched intercellular domains. These results provide the first evidence that endogenous, epidermis-derived skin lipids may contribute to cutaneous antimicrobial resistance.

Fatty Acids, Nonesterified↗
PubMed1986

Output of triglyceride from the sebaceous gland and to the skin surface of cattle.

Radiolabelled fatty acids, when injected intradermally into cattle skin, were largely incorporated into the triglyceride and phospholipid fractions of the sebaceous gland lipids. Linoleic acid was incorporated into the triglycerides to a greater extent than oleic or palmitic acids, whereas the phospholipids had a greater affinity for palmitic acid. The peak uptake of linoleic acid into the glandular triglyceride fraction was at about 61 hours compared with 52 hours and three hours for oleic and palmitic acids. Radioactively 14C labelled triglycerides appeared on the skin surface within one day of intradermal injection of 14C linoleic acid. At an ambient temperature of 20 degrees C, a single output-peak occurred at nine days while at 35 degrees C two peaks at four and eight to nine days were observed. From the data an estimate of 6.5 days for the mean storage time of sebum triglycerides in the hair follicle canal at 20 degrees C has been made.

Animals↗