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At least 559 records · Page 31Linked to original sources
PubMedDate not supplied

Pharmacological evaluation of membrane-moderated transdermal system of glipizide.

1. Membrane-moderated transdermal systems of glipizide were prepared using drug-containing carbopol gel (drug reservoir) and ethyl cellulose, as well as Eudragit RS-100, Eudragit RL-100 (Rohm Pharma, Darmstadt, Germany) and ethylene vinyl acetate (EVA; 2, 9 and 19% vinyl acetate content) rate-controlling membranes, and were subsequently evaluated in vitro (drug content and drug permeation studies) and in vivo (acute and long-term hypoglycaemic activity, effect on glucose tolerance, biochemical and histopathological studies, skin irritation test and pharmacokinetic studies in mice). 2. The drug content of the systems was found to be more than 99%. Variations in drug permeation patterns were observed among the formulations containing different rate-controlling membranes. 3. The system with the EVA (19% vinyl acetate) rate-controlling membrane was selected for in vivo experiments. This transdermal system produced better improvement with respect to hypoglycaemic activity, glucose tolerance and tested biochemical, histopathological and pharmacokinetic parameters all compared with oral administration and exhibited negligible skin irritation. 4. The transdermal system successfully prevented severe hypoglycaemia in the initial hours and it was also effective for chronic application.

Administration, Cutaneous↗
PubMed2005

The clinical benefit of moisturizers.

UNLABELLED: Moisturizing creams marketed to consumers often contain trendy ingredients and are accompanied by exciting names and attractive claims. Moisturizers are also an important part of the dermatologist's armamentarium to treat dry skin conditions and maintain healthy skin. The products can be regarded as cosmetics, but may also be regulated as medicinal products if they are marketed against dry skin diseases, such as atopic dermatitis and ichthyosis. When moisturizers are used on the so-called dry skin, many distinct disorders that manifest themselves with the generally recognized symptoms of dryness are treated. Dryness is not a single entity, but is characterized by differences in chemistry and morphology in the epidermis depending on the internal and external stressors of the skin. Patients and the society expect dermatologists and pharmacists to be able to recommend treatment for various dry skin conditions upon evidence-based medicine. LEARNING OBJECTIVE: Upon completing this paper, the reader should be aware of different types of moisturizers and their major constituents. Furthermore, s/he will know more about the relief of dryness symptoms and the functional changes of the skin induced by moisturizers.

Administration, Topical↗
PubMed1998

Modified topical photodynamic therapy of superficial skin tumors, utilizing aminolevulinic acid, penetration enhancers, red light, and hyperthermia.

BACKGROUND: Photodynamic therapy (PDT) is a noninvasive selective therapy for a specific group of skin tumors. OBJECTIVE: In this study we used a modified topical medication in which ethyleneamine tetra acetic acid (EDTA) and dimethylsulphoxid (DMSO) were added to 5-aminolevulinic acid 20% (ALA) followed by exposure to a novel high output light source emitting red and infrared irradiation. METHODS: ALA 20%-EDTA 2%-DMSO 2% in a water in oil cream base was applied to the tumors. After 12 hours the tumor was exposed to red (585-720 nm; 150 mW/cm2) and near infrared irradiation (1.25-1.6 mm; 50 mW/cm2) for 10-15 minutes by the VersaLight incoherent filtered light source. RESULTS: Complete responses were achieved after one to three ALA-PDT treatments in 26/31 lesions of superficial or small nodular basal cell carcinoma (BCC) (84%), and in four of five in superficial squamous cell carcinoma (SCC) (80%). Complete clearance was achieved in one patient with Bowen's disease of the penis. CONCLUSIONS: Topical PDT utilizing ALA 20%-EDTA 2%-DMSO 2% as the photosensitizer and VersaLight as the light source is a noninvasive, nearly painless treatment with excellent therapeutic and cosmetic results. Our data show the efficiency of this therapy for patients with certain subtypes of BCC, SCC, and Bowen's disease.

Administration, Cutaneous↗
PubMed1986

The effects of wearing diapers on skin.

Wearing dry and wet cloth and disposable diaper materials has certain effects on the degree of skin wetness. These, in turn, affect the coefficient of skin friction, the skin's susceptibility to abrasion damage, its permeability, and its support of microbial growth. These effects were explored using an adult model wearing forearm patches. The adult model was validated by comparisons of skin wetness and friction values for infants and adults determined under similar conditions. Skin wetness was proportional to diaper wetness. With increased skin wetness, there were increased coefficients of friction and increased abrasion damage, skin permeability, and microbial growth. Cloth diaper material produced wetter skin than did disposable diaper material at equivalent loadings.

Adult↗
PubMed1986

Etiologic factors in diaper dermatitis: the role of urine.

Diaper dermatitis may result after repeated or prolonged contact of skin with urine and feces. A hairless mouse model was used to elucidate the role of urine in this process. The results of this work suggest that an important function of urine in the etiology of diaper dermatitis is to increase the pH of the diaper environment by breaking down urea in the presence of fecal urease. This rise in pH increases the activities of fecal proteases and lipases, which can damage skin. Urine can also increase the permeability of diapered skin to irritants and can directly irritate skin when exposure is prolonged.

Ammonia↗
PubMed1986

Etiologic factors in diaper dermatitis: the role of feces.

While the etiology of diaper dermatitis in infants is complex, it is generally believed to involve an interaction between skin and irritants in feces and urine. Proteases and lipases were identified as the major irritants in the feces of infants, and bile salts were found to potentiate the damage produced by the action of fecal enzymes on skin. Fecal enzymes also increased the permeability of skin, thereby increasing potential susceptibility to other irritants in the diaper environment.

Animals↗
PubMed1991

Dry skin of newborn infants: functional analysis of the stratum corneum.

Our clinical observations disclosed that most newborn infants showed scaling on at least some parts of the body. To clarify the mechanism for such xerosis, we performed measurements of high-frequency conductance (Gx), which assesses the skin surface hydration and evaporative water loss from the skin. The skin of newborns showed surprisingly lower Gx values and evaporative water loss than those of adults or 1- to 6-month-old infants in a warm environment. These findings may be explained partly by low eccrine activity, which has been reported as characteristic of newborn skin. However, defective stratum corneum function, such as reduced water-holding capacity as demonstrated by the in vivo water sorption-desorption test, also seems to be responsible for the development of dry skin in newborns.

Child↗
PubMed1989

Minimum eliciting patch test concentrations of cobalt.

In sensitized subjects, minimum eliciting levels of cobalt were estimated using patch tests with aqueous cobalt chloride on both normal skin and on skin pretreated in various ways to enhance penetration and reactivity. 6 reacted to 10,000 ppm and 1 gave an equivocal reaction to 1000 ppm aq. cobalt. Pretreatment of the patch test site for 24 h with surfactant enhanced reactivity, reducing the minimum eliciting concentration to 1000 ppm cobalt chloride in 1 subject, to 100 ppm in 2 subjects, and in 3 subjects to 10 ppm aqueous cobalt chloride. No reactions were obtained at 1 ppm. EDTA was effective in reducing the response to aqueous cobalt.

Adult↗
PubMed1998

Correlation between percutaneous penetration of methyl nicotinate and sensitive skin, using laser Doppler imaging.

Cutaneous penetration of methyl nicotinate has been investigated in 20 women divided into reactors and non-reactors on the basis of response to 10% aqueous solution of lactic acid. The vasodilation induced was measured using a laser Doppler perfusion imager (LDPI) every 5 min for 1 h after application of methyl nicotinate. The intensity and duration of inflammation generated by methyl nicotinate were used to assess penetration of this chemical in persons with sensitive skin compared to those with normal skin. Significant differences were found between reactors and non-reactors. Reactors showed a significantly increased intensity of response to methyl nicotinate as early as 5 min after application, and for 30 min afterwards, though the duration of inflammation in these 2 groups was the same. Correlation between increased penetration of methyl nicotinate and skin response to lactic acid may suggest increased penetration of water-soluble chemicals in individuals with sensitive skin.

Administration, Cutaneous↗
PubMed2006

Skin sensitization potency of methyl methacrylate in the local lymph node assay: comparisons with guinea-pig data and human experience.

There is compelling evidence that contact allergens differ substantially (by 4 or 5 orders of magnitude) with respect to their inherent skin-sensitizing potency. Relative potency can now be measured effectively using the mouse local lymph node assay (LLNA) and such data form the basis of risk assessment and risk management strategies. Such determinations also facilitate distinctions being drawn between the prevalence of skin sensitization to a particular contact allergen and inherent potency. The distinction is important because chemicals that are implicated as common causes of contact allergy are not necessarily potent sensitizers. One example is provided by nickel that is undoubtedly a common cause of allergic contact dermatitis, but is a comparatively weak sensitizer in predictive tests. In an attempt to explore other examples of contact allergens where there may exist a discrepancy between prevalence and potency, we describe here analyses conducted with methyl methacrylate (MMA). Results of LLNA studies have been interpreted in the context of historical clinical data on occupational allergic contact dermatitis associated with exposure to MMA.

Allergens↗
PubMed2006

Generation and distribution of reactive oxygen species in the skin of hairless mice under UVA: studies on in vivo chemiluminescent detection and tape stripping methods.

Although the formation of reactive oxygen species (ROS) in the skin induced by the ultraviolet (UV) light has been shown to lead to many cutaneous disorders, skin cancer and photoageing, the mechanism and distribution of ROS generation has not yet been definitively determined. In the present study, we examined the distribution of UVA-induced ROS in the skin of live hairless mice, using our proposed in vivo imaging chemiluminescent (CL) method to detect ROS combined with a CL probe (cypridina hilgendorfii luciferin analogue; CLA) and tape stripping (TS) technique. The CL intensities in the skin of live hairless mice were confirmed to significantly increase by UVA exposure. When TS was conducted five times in a maximum level after CL measurement following UVA exposure and subsequent CLA application, CL intensities due to UVA-induced ROS generation in the residual skin decreased to 10% of the original levels; and those in the stripped skin on each tape decreased in the stripped order such as 52%, 16%, 11%, 6% and 5%. Next, CLA was applied and then CL intensities were measured in the residual skin after advance 1, 3 and 5 tape strippings, and CL intensities due to ROS were detected primarily in the outer layer of the skin. On the basis of these results, we concluded that ROS induced by UVA exposure occurs and distributes in the outermost layer of the stratum corneum.

Adhesives↗
PubMed1997

Diagnosis of photosensitivity to flupenthixol by photoprick testing.

We report the case of a 38-year-old patient with an erythematous eruption, initially confined to photo-exposed areas and then becoming more generalized, which was attributable to flupenthixol, a thioxanthene derivative used for its neuroleptic properties. The compound has the same polycyclic aromatic hydrocarbons as phenothiazines, but without any cross-reaction in our patient. A photoallergic cause for the eruption was verified on clinical, histological and photobiologic grounds. Photopatch tests were negative, but photoprick testing was positive after UV irradiation of the test site. Photopatch test methods using better skin penetration have been already reported for testing drug photosensitivity. Photoprick testing combines better penetration with greater ease of use.

Adult↗
PubMed2004

Assessment of spray application of Saint GERVAIS water effects on skin wettability by contact angle measurement comparison with bidistilled water.

BACKGROUND: The skin is responsible for protecting the body from physical, chemical and microbial injuries. The stratum corneum is the top layer of the epidermis and it plays a key role in helping to contain moisture. When the skin becomes damaged, its ability to perform these functions is compromised. Dry skin is a common form of skin damage. Contact angle 0 between a surface and water is a good indicator of hydrophobic or hydrophilic tendency of surfaces. OBJECTIVE: To quantify the influence of spray application of an isotonic mineral water (Saint GERVAIS water) on the hydrophobic tendency of dry skin and to compare spreading of both types of water on the skin through 0 measurement of each water drop on the skin before and after mineral spray application. MATERIALS AND METHODS: Contact angles theta between skin surface and the two types of water (bidistilled and mineral water) were measured before and after application of mineral water by a system allowing the measurement of theta in vivo and in vitro. The cutaneous hydration, the temperature and pH were also measured before and after mineral water application. RESULTS: As for the application of mineral water, the cutaneous pH significantly increased so the strong skin acidity decreased. The cutaneous temperature was modified (a decrease of 2 degrees C was noted) and the cutaneous hydration was also increased (+47AU). The hydro-phobic tendency of the dry skin tested in this study was strongly decreased after mineral water application. This parameter was illustrated by a decrease of contact angle theta value. CONCLUSION: Saint GERVAIS water application allowed a regulation of skin pH, a fresh sensation on the skin and an increase in the cutaneous hydration. Moreover, the contact angle measurement with bidistilled water illustrated the increased wettability of the skin.

Administration, Topical↗