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1.
Arch Dermatol Res ; 299(10): 499-505, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17960402

RESUMEN

The appearance of hair plays an important role in people's overall physical appearance and self-perception. Silicon (Si) has been suggested to have a role in the formation of connective tissue and is present at 1-10 ppm in hair. Choline-stabilized orthosilicic acid ("ch-OSA") is a bioavailable form of silicon which was found to improve skin microrelief and skin mechanical properties in women with photoaged skin. The effect of ch-OSA on hair was investigated in a randomized, double blind, placebo-controlled study. Forty-eight women with fine hair were given 10 mg Si/day in the form of ch-OSA beadlets (n = 24) or a placebo (n = 24), orally for 9 months. Hair morphology and tensile properties were evaluated before and after treatment. Urinary silicon concentration increased significantly in the ch-OSA supplemented group but not in the placebo group. The elastic gradient decreased in both groups but the change was significantly smaller in the ch-OSA group (-4.52%) compared to placebo group (-11.9%). Break load changed significantly in the placebo group (-10.8%) but not in the ch-OSA supplemented group (-2.20%). Break stress and elastic modulus decreased in both groups but the change was smaller in the ch-OSA group. The cross sectional area increased significantly after 9 months compared to baseline in ch-OSA supplemented subjects but not in the placebo group. The change in urinary silicon excretion was significantly correlated with the change in cross sectional area. Oral intake of ch-OSA had a positive effect on tensile strength including elasticity and break load and resulted in thicker hair.


Asunto(s)
Suplementos Dietéticos , Cabello/efectos de los fármacos , Ácido Silícico/farmacología , Adolescente , Adulto , Colina , Método Doble Ciego , Femenino , Cabello/anatomía & histología , Cabello/fisiología , Humanos , Persona de Mediana Edad , Ácido Silícico/química , Ácido Silícico/farmacocinética , Resistencia a la Tracción/efectos de los fármacos
2.
Arch Dermatol Res ; 297(4): 147-53, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16205932

RESUMEN

Chronic exposure of the skin to sunlight causes damage to the underlying connective tissue with a loss of elasticity and firmness. Silicon (Si) was suggested to have an important function in the formation and maintenance of connective tissue. Choline-stabilized orthosilicic acid ("ch-OSA") is a bioavailable form of silicon which was found to increase the hydroxyproline concentration in the dermis of animals. The effect of ch-OSA on skin, nails and hair was investigated in a randomized, double blind, placebo-controlled study. Fifty women with photodamaged facial skin were administered orally during 20 weeks, 10 mg Si/day in the form of ch-OSA pellets (n=25) or a placebo (n=25). Noninvasive methods were used to evaluate skin microrelief (forearm), hydration (forearm) and mechanical anisotropy (forehead). Volunteers evaluated on a virtual analog scale (VAS, "none=0, severe=3") brittleness of hair and nails. The serum Si concentration was significantly higher after a 20-week supplementation in subjects with ch-OSA compared to the placebo group. Skin roughness parameters increased in the placebo group (Rt:+8%; Rm: +11%; Rz: +6%) but decreased in the ch-OSA group (Rt: -16%; Rm: -19%; Rz: -8%). The change in roughness from baseline was significantly different between ch-OSA and placebo groups for Rt and Rm. The difference in longitudinal and lateral shear propagation time increased after 20 weeks in the placebo group but decreased in the ch-OSA group suggesting improvement in isotropy of the skin. VAS scores for nail and hair brittleness were significantly lower after 20 weeks in the ch-OSA group compared to baseline scores. Oral intake of ch-OSA during the 20 weeks results in a significant positive effect on skin surface and skin mechanical properties, and on brittleness of hair and nails.


Asunto(s)
Colina , Cabello/efectos de los fármacos , Uñas/efectos de los fármacos , Ácido Silícico/administración & dosificación , Piel/efectos de los fármacos , Piel/efectos de la radiación , Rayos Ultravioleta/efectos adversos , Administración Oral , Adulto , Anciano , Fenómenos Biomecánicos , Método Doble Ciego , Cara , Femenino , Cabello/patología , Cabello/fisiopatología , Humanos , Hidroxiprolina/metabolismo , Persona de Mediana Edad , Uñas/patología , Uñas/fisiopatología , Ácido Silícico/farmacología , Ácido Silícico/uso terapéutico , Silicio/sangre , Piel/metabolismo , Piel/patología , Factores de Tiempo
3.
J Dermatol ; 25(6): 412-4, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9675352

RESUMEN

Hydroquinone is a well known reagent used in the treatment of pigmentation disorders. The instability of the quinones and the required active concentration make topical treatment rather difficult. We tested the efficacy of an ascorbate-phytohydroquinone complex that inhibits the synthesis of melanin and promotes the degradation of the existing melanin. Lentigo senile lesions were evaluated before and after 1 month of treatment. Objective skin color evaluation was performed instrumentally. After one month of treatment, a clear depigmentation of the macules was measured. None of the volunteers reported any side effects from the prolonged treatment with the hydroquinone containing product.


Asunto(s)
Fármacos Dermatológicos/uso terapéutico , Glucósidos/uso terapéutico , Lentigo/tratamiento farmacológico , Administración Cutánea , Anciano , Anciano de 80 o más Años , Apiaceae , Ácido Ascórbico/administración & dosificación , Ácido Ascórbico/uso terapéutico , Peróxido de Benzoílo/uso terapéutico , Citrus , Colorimetría , Fármacos Dermatológicos/administración & dosificación , Combinación de Medicamentos , Femenino , Estudios de Seguimiento , Glucósidos/administración & dosificación , Humanos , Hidroquinonas/administración & dosificación , Hidroquinonas/uso terapéutico , Masculino , Melaninas/antagonistas & inhibidores , Melaninas/metabolismo , Persona de Mediana Edad , Aceites Volátiles/uso terapéutico , Oxiquinolina/uso terapéutico , Extractos Vegetales/uso terapéutico , Pigmentación de la Piel/efectos de los fármacos
4.
Skin Res Technol ; 3(3): 154-60, 1997 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27333491

RESUMEN

BACKGROUND/AIMS: The visual appearance of cellulite or the'orange peel'look of skin is a common cosmetic problem for many women. Cellulite, or more correctly lipodystrophy, is a modification of the adipose tissue, whereby the fat lobules are swollen as the result of a disturbed blood and lymph micro-circulation and fibrosclerose of connective tissue. In the wealthy diversity of products against cellulite, objective methods to measure their efficacy are of growing importance. The purpose of this study is to establish the effectiveness of a skin massage treatment by quantifying the changes in the skin via ultrasound imaging, during and following treatment. METHODS: Using 20 MHz C-mode ultrasound scanning, a three-dimensional subsurface is constructed that represents the dermis-hypodermis tissue interface. In normal cellulite-free skin, this interface is smooth. In the case of cellulite, however, the dermis-hypodermis junction appears as an irregular surface. Qualitatively, the effect of cellulite treatment is inferred from changes in the shape of this junction. In order to quantify the effect, we chose to monitor the junction area. For the treatments, we used a specially designed handheld electro-mechanical massage device that was moved along the thigh. Treatments were conducted for 3 months, three times a week, during 15 min on each upper leg of 20 healthy female volunteers with moderate symptoms of cellulite (Curri's classification 1-2). Ultrasound measurements were performed monthly, and continued for 2 months after the treatments were stopped. RESULTS: The results, on average, indicate a significant smoothening of the dermis-hypodermis surface (relative surface area reduction 34+3%, 50±3% and 56±2% after 1, 2 and 3 months of treatment, respectively). The smoothening can be described by a mono-exponential function with a time constant of 1.1 month. After the treatments were discontinued, the relative surface area gradually increased (with a time constant of 2.6 month), which indicates that the effect of massage is not permanent. CONCLUSION: Treatment of cellulite by means of an electro-mechanical skin fold massage apparatus significantly smoothens the structure of the dermis-hypodermis interface. Three-dimensional ultrasound imaging of the dermis-hypodermis junction could serve as an objective method to monitor the effectiveness of cellulite treatment.

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