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Reduction of sebaceous secretion in hyperseborrheic skin by a synthetic steroid: promestriene.

Using the 'ground glass method', the forehead seborrheic index of 72 patients was determined before and during local treatment with promestriene 1% in a o/w base. In hyperseborrheic patients a significant decrease of the seborrheic index was obtained from the 3rd week of treatment and maintained for all its duration, while in normoseborrheics no change was observed under the same conditions. It may be concluded that promestriene reduces the sebum secretion but only in hyperseborrheic patients.

Dermatitis, Seborrheic↗

Why do we have apocrine and sebaceous glands?

The secretions of sebaceous and apocrine glands fulfil an important thermoregulatory role in cold-stressed and heat-stressed hunter-gatherers. In hot conditions the secretions emulsify eccrine sweat and thus encourage the formation of a sweat sheet and discourage the formation and loss of sweat drops from the skin. In colder conditions sebum changes its nature and repels rain from skin and hair.

Animals↗

Isotretinoin in severe, recalcitrant cystic acne: a review.

Isotretinoin, an isomer of retinoic acid, recently has been approved by the Food and Drug Administration for treatment of severe, recalcitrant acne. The most impressive effects include inhibition of sebum production and a reversible decrease in sebaceous gland size. Isotretinoin has proved to be an effective drug; response to therapy has been seen in virtually 100 percent of patients treated. Almost all patients experience reversible cutaneous and mucous-membrane symptoms while on isotretinoin treatment. Other common side effects include conjunctivitis (38 percent) and eye irritation (50 percent). The recommended dosage is 1-2 mg/kg/d for no longer than 16 weeks. Isotretinoin is currently the treatment of choice for severe, recalcitrant acne; however, because of potential side effects associated with retinoids, isotretinoin should be reserved for those patients who are unresponsive to conventional therapy, including topical and systemic antibiotics.

Acne Vulgaris↗

Physiological and subjective responses to low relative humidity.

In order to investigate the influence of low relative humidity, we measured saccharin clearance time (SCT), frequency of blinking, heart rate (HR), blood pressure, hydration state of skin, transepidermal water loss (TEWL), recovery sebum level and skin temperature as physiological responses. We asked subjects to judge thermal, dryness and comfort sensations as subjective responses using a rating scale. Sixteen non-smoking healthy male students were selected. The pre-room conditions were maintained at an air temperature (Ta) of 25 degrees C and a relative humidity (RH) of 50%. The test room conditions were adjusted to provide a Ta of 25 degrees C and RH levels of 10%, 30% and 50%.RH had no effect on the activity of the sebaceous gland and on cardiovascular reactions like blood pressure and HR. However, it was obvious that low RH affects SCT, the dryness of the ocular mucosa and the stratum corneum of the skin and causes a decrease in mean skin temperature. Under 30% RH, the eyes and skin become dry, and under 10% RH the nasal mucous membrane becomes dry as well as the eyes and skin, and the mean skin temperature decreases. These findings suggested that to avoid dryness of the eyes and skin, it is necessary to maintain an RH greater than 30%, and to avoid dryness of the nasal mucous membrane, it is necessary to maintain an RH greater than 10%. Subjects felt cold immediately after a change in RH while they had only a slight perception of dryness at the change of humidity.

Adult↗

Current concepts of the pathogenesis of acne: implications for drug treatment.

The pathogenesis of acne is complex, with strong evidence supporting the involvement of sebaceous hyperplasia, follicular hyperkeratinisation, bacterial hypercolonisation, as well as immune reactions and inflammation. High sebum concentrations and follicular hyperkeratinisation lead to a change of the follicular milieu with consecutive proliferation of bacteria, chiefly Propionibacterium acnes. This leads to further increased production of the pro-inflammatory cytokines interleukin-1alpha and tumour necrosis factor alpha by T cells and keratinocytes, leading to proliferation of both cell types. Follicular keratinocytes fail to differentiate by apoptosis and produce hypergranulosis similar to the impermeable skin outer layer, resulting in the formation of microcomedones. Further inflammatory responses lead to the development of increasing degrees of severity in inflammatory forms of acne. Retinoids aid the differentiation and reduce the hyperproliferation of keratinocytes, and can inhibit the migration of leucocytes. Combination therapy using retinoids plus benzoyl peroxide or antibacterials can treat existing acne lesions faster than the individual agents alone and can also prevent the development of new lesions. The new retinoids (e.g. adapalene) have not only the typical potent comedolytic activity but also anti-inflammatory effects. When added to antibacterial therapy, topical retinoids demonstrate faster and significantly greater reduction of inflammatory acne lesions and comedones than antibacterials alone.

Acne Vulgaris↗

Mature cystic teratomas of the ovary without fat in the cystic cavity: MR features in 12 cases.

OBJECTIVE: The diagnosis of mature cystic teratoma may be overlooked in the small number of cases that do not contain fat in the lumen of the cyst. The purpose of this study was to evaluate the MR appearance of mature cystic teratomas containing little or no fat and to determine the value of gradient-echo MR imaging for detection of small amounts of fat. MATERIALS AND METHODS: In a review of pathologic specimens of 78 mature cystic teratomas, we found 12 tumors without fatty fluid (sebum) in their cystic cavity. Histologically, a small amount of fat was present in the wall of the cyst in each case. We retrospectively reviewed MR images of these tumors. In seven tumors with small amounts of hyperintense tissue on T1-weighted MR images, opposed-phase and in-phase gradient-echo MR images were obtained in order to verify the presence of fat. RESULTS: All 12 lesions were hypointense on T1-weighted MR images and markedly hyperintense on T2-weighted images, indicating that the cystic cavity contained aqueous fluid. Fatty tissue was not identified in the lumen or wall of the cyst on MR images in five of the 12 tumors. In seven tumors, MR images showed small hyperintense areas in the walls of the cysts. These hyperintense signals were canceled on opposed-phase gradient-echo images. Characteristic MR findings for mature cystic teratoma, such as reversed chemical-shift artifact, gravity-dependent layering, or dermoid plug, were not observed in any of the lesions. CONCLUSION: MR images in some cases of mature cystic teratomas may show aqueous fluid within the lumen of the cyst. In such cases, detection of fat in the cyst wall, especially with gradient-echo MR imaging, may help to establish the diagnosis.

Adipose Tissue↗

Intracutaneous transport of orally administered fluconazole to the stratum corneum.

Fluconazole administered at 150 mg/week for 1-5 weeks is effective orally against dermatophytes and yeast in stratum corneum. Clinical and mycological cure rates approach 90%, but the precise distribution of the drug within various layers of skin is uncertain. We administered fluconazole at 150 mg/week for 2 weeks to 5 volunteers. Distribution of fluconazole in biopsies of skin was imaged by energy dispersive analysis of X-rays (EDX) and transmission electron microscopy, and in cells by electron energy-loss spectroscopy (EELS). Eight hours after a second dose, EDX showed fluconazole highest and homogeneously distributed in stratum corneum, lower in the rest of the epidermis, and lowest in dermis. The highest fluconazole levels detected by EELS were in cytoplasmic inclusions of sweat and sebaceous glands and less in keratinocytes and dermal collagen. We conclude that fluconazole delivered to stratum corneum by direct diffusion from capillaries and in sweat is also in all likelihood transported in sebum.

Administration, Oral↗

[Effects of various solvents on skin surface lipid composition].

1. Samples of cutaneous sebum were taken from different skin regions, according to the method of Herrmann and Prose. 2. Some samples were removed from the skin using diethyl ether, while others were removed under similar conditions, with cyclohexane. 3. As a rule, thin-layer chromatography revealed darker, clearer and more numerous bands after the use of diethyl ether, than after the use of cyclohexane. However, some exceptions were seen. 4. The chromatograms showed individual differences while the differences between the samples taken from different skin regions of one and the same person were less considerable. 5. Despite the individual differences, the samples taken from persons without skin diseases showed some characteristic features.

Adult↗

Plasma beta-MSH levels in acne vulgaris.

Plasma beta-MSH levels and sebum excretion rates (SER) were measured in thirty male and twelve female patients with acne vulgaris. The mean SER in both male and female patients was significantly increased as compared to normal control levels. Plasma beta-MSH levels were normal in male and female patients with acne and showed no correlation with the SER. The SER that occurs in acne cannot therefore be explained by an increased secretion of beta-MSH.

Acne Vulgaris↗

A microbial etiology of acne?

The view is advanced that sebum as originally produced must contain materials, other than lipids, which may serve as a selective substrate for growth of bacteria and yeasts. Growth of large numbers of P. acnes and P. granulosum in some follicles is considered to place those follicles at risk of undergoing pathological changes. Deleterious products of bacterial growth could be not only lipase and free fatty acids, but also other enzymes as well as bacterial antigens and unspecified toxins or irritants. The possibility is suggested that follicles heavily infested with P. acnes and P. granulosum may be identified by their reddish fluorescence under ultraviolet light, thus permitting identification and study of those which are at risk. Antibiotics may be helpful in reducing the formation of harmful bacterial products during continued growth of the organisms. The eventually self-limiting nature of the disease may be due to the immune response to bacterial products, or to an accommodation of the follicular epithelium to the long-continued presence of irritant materials within the follicle.

Acne Vulgaris↗

[The effect of cosmetics and dermatologic agents on skin lipids].

The composition of stratum corneum lipids and of sebum lipids is described with respect to their biological function, with special reference to dry skin. In this context, we discuss desiccation and lipid removal by surfactants and the protective and refatting effects of oil bath products and other lipid-containing preparations for topical use.

Cell Membrane Permeability↗

New treatment for seborrheic alopecia: the ligature of the arteries of the scalp.

Bilateral ligature of the superficial temporal arteries and of the posterior auricular arteries is proposed as a treatment for seborrheic alopecia. The arterial circulatory dynamics are, thus, replaced by capillary circulatory dynamics. Hypoxia is produced which inhibits enzymatic systems and lessens nocuous action of androgen and lipid factors on the pilosebaceous effectors. The histologic study shows that the production of sebum is greatly reduced and the condition of the hair follicle is strikingly improved.

Alopecia↗

The pathophysiology of acne.

Acne is a multifactorial inflammatory disease affecting pilosebaceous follicles. The initial event in the development of an acne lesion is abnormal desquamation of the keratinocytes that line the sebaceous follicle, which creates a microplug or microcomedo. An increase in circulating androgens at the onset of puberty stimulates the production of sebum into the pilosebaceous unit. These events combine to create an environment within the pilosebaceous unit that is favorable for the colonization of the commensal bacteria, Propionibacterium acnes. With proliferation, P acnes secretes various inflammatory molecules and chemotactic factors that initiate and perpetuate the local inflammatory response and possibly induce keratinocyte hyperproliferation as well.

Acne Vulgaris↗

Combination therapy is the standard of care.

Acne is a multifactorial disease characterized by abnormalities in sebum production, follicular epithelial desquamation, bacterial proliferation, and inflammation. Despite these multiple pathogenic factors, most current therapies for acne do not target all 4 areas of acne pathophysiology. Combination therapies using agents with complementary mechanisms of action increasingly are recognized as an effective strategy for treating acne. Several common regimens have shown this multiple-target efficacy, including the combination of a topical antibiotic with benzoyl peroxide. In combination, these agents produce greater and faster results than when each is used as monotherapy. For both initial treatment and maintenance therapy, the ideal combination regimen is often a topical antibiotic and benzoyl peroxide product plus a retinoid that is appropriate for the patient's skin type. Combination regimens should be tailored to the individual patient, bearing in mind the number and types of prevailing lesions and the skin type. Because the vehicle for each agent may have an impact on tolerability, one should pay attention to the combination of vehicles and patient care practices to maximize tolerability.

Acne Vulgaris↗

Clinical and laboratory studies on treatment with 20% azelaic acid cream for acne.

In a series of investigations using 20% azelaic acid cream as a therapy for acne, it was found that the treatment, compared with its placebo, significantly reduced inflamed lesions after 1 month and non-inflamed lesions after 2 months. No changes in sebum excretion rate occurred, but a significant reduction, 15.9 to 10.5%, of free fatty acids of skin surface lipid was detected after 1 month. The follicular Micrococaceae density was significantly reduced after 1 month, and after 2 months there was a significant reduction in follicular Propionibacterium spp density. The final reductions were 2,500 and 44 fold, respectively.

Acne Vulgaris↗

[Mechanism of azelaic acid action in acne].

The physiopathologic mechanism of acne seems to be dependent on four main factors: a) sebum production and excretion; b) type of keratinization of the follicular channel; c) microbial colonization of the pilosebaceous unit and d) inflammatory reaction of the perifollicular area. Azelaic acid is effective in the treatment of acne because it possesses an activity against all of these factors. Azelaic acid is a competitive inhibitor of mitochondrial oxidoreductases and of 5 alpha-reductase, inhibiting the conversion of testosterone to 5-dehydrotestosterone. It also possesses bacteriostatic activity to both aerobic and anaerobic bacteria including Propionibacterium acnes. Azelaic acid is an anti-keratinizing agent, displaying antiproliferative cytostatic effects on keratinocytes and modulating the early and terminal phases of epidermal differentiation.

Acne Vulgaris↗

Occurrence of Demodex in nose follicles of outpatients attending an otorhinolaryngology clinic.

The occurrence of Demodex in sebum from nasolabial folds was studied in fifty outpatients attending an otorhinolaryngology clinic. Thirty-one male and nineteen female patients aged fifteen to eighty years were examined. Twenty percent (eight men and two women) showed positive findings, demonstrating one to six parasites per specimen. A higher detection rate was found in older patients, and more mite particles were seen in subjects with otitis media. It is suggested that examination of nasolabial folds may serve as a screening test for the possible presence of Demodex in the ears.

Adolescent↗

[Efficacy of fenticonazole in patients with pityriasis versicolor].

Thirty patients suffering from Pityriasis versicolor were treated with fenticonazole in cream or lotion form with two applications a day. At microscopy, Malassezia furfur was encountered in 25 cases and Pityrosporum orbiculare in 5. Disappearance of the yeast was obtained on average in 2 weeks of treatment. Measurement of sebum content with a Sebumeter apparatus did not reveal significant difference (p greater than 0.05) between patients suffering from Pityriasis versicolor and controls and in treated patients, in the course of topical therapy.

Administration, Cutaneous↗