Gary L. Grove

Topical tretinoin for photoaged skin.

Daily topical application of 0.05% tretinoin in a cream base was compared with its vehicle with regard to moderation of photoaging changes of the face and forearms. In comparison with the control tissue, tretinoin-treated tissue examined by light and electron microscopy showed the following effects: replacement of the atrophic epidermis by hyperplasia, elimination of dysplasia and atypia, eradication of microscopic actinic keratoses, uniform dispersion of melanin granules, new collagen formation in the papillary dermis, new vessel formation (angiogenesis), and exfoliation of retained horn in the follicles. Physiologic studies demonstrated: increased blood flow and dermal clearance, increased transepidermal water loss, and greater permeability and reactivity. It was concluded that topical tretinoin is capable of at least partly reversing the structural damages of excessive sunlight exposure and may be useful in decelerating the photoaging process.

Optical profilometry: an objective method for quantification of facial wrinkles.

Facial fine lines and wrinkles can be faithfully captured by silicone rubber impression materials. Computerized digital image processing of such specimens provides objective measurement of the skins topography, which has a significant degree of correlation with clinical grading. Optical profilometry provides a dimension of objectivity that can complement clinical assessment in the study of agents that may be useful in the therapy of photodamaged skin.

Treatment of photodamaged facial skin with topical tretinoin

A 6-month, randomized, double-blind, vehicle-controlled study was conducted with 0.05% tretinoin cream once daily in the treatment of photodamaged facial skin. Significant amelioration of many of the signs of photodamage were achieved with minimal side effects. Clinical grading showed significant improvement both in the assessments based on changes in clinical scores and in pre- and posttreatment comparisons of standardized photographs. Fine wrinkling, coarse wrinkling, sallowness, looseness, and hyperpigmentation were significantly improved with tretinoin therapy. Furthermore, a self-appraisal questionnaire indicated that tretinoin-treated patients, but not vehicle-treated patients, were able to perceive improvement in their facial appearance. An objective method based on digital image processing of silicone rubber casts obtained from the crows-feet area also indicated that the skin surface topography was smoother and less wrinkled in the tretinoin-treated group compared with the vehicle-control group.

Physiologic and Microbiologic Changes in Skin Related to Frequent Handwashing

Handwashing practices may be adversely influenced by the detrimental effects of handwashing on skin. A protocol was developed to assess the physiologic and microbiologic effects of frequent handwashing. Fifty-two female volunteers washed their hands 24 times per day for 5 days. Five agents were tested: water alone, non-medicated bar soap, a chlorhexidine-containing antiseptic, and two agents containing povidone-iodine (one currently available on the market and one being tested for possible marketing). Some damage to the outer membrane of skin, the stratum corneum, occurred in all groups. There were significant changes in the amount of evaporation water loss (p = .001) and in self assessments of skin condition (p = .005) from pre-to-post test for the entire group. Skin damage was also assessed by visualizing desquamating stratum corneum cells, which are shed in large aggregates when detergents injure skin. Significantly less such shedding occurred in subjects using water alone, bar soap, and the chlorhexidine formulation (p = .02). Greater antimicrobial activity of an agent was not correlated with increased skin trauma. We have quantitated, using objective physiologic parameter, the skin damage that occurs during even a short period of frequent handwashing. We recommend that further studies using the methods described be conducted to quantitate skin damage over longer periods of time, more closely resembling handwashing practices of health care personnel.

Physiologic, microbiologic, and seasonal effects of handwashing on the skin of health care personnel.

The handwashing practices of 22 personnel on an oncology unit in an urban medical center were studied for 2 months. During 891 person-hours of observation, 986 handwashes were observed. Subjects washed a mean of 1.1 times an hour for a mean of 13.2 seconds. Reported and observed handwashing behavior was only moderately correlated (p = 0.05 for frequency, 0.30 for duration of handwashing). Physicians washed significantly less often (p less than 0.001), but more thoroughly (p less than 0.001), than did nurses. Nurses washed more often after minimal or no patient contact than did physicians (p less than 0.001). Individuals were very consistent in their handwashing technique. A total of 558 isolates were recovered from 158 hand cultures. The mean log count was 4.88, with no significant difference between physicians and nurses. Coagulase-negative staphylococci isolated from hands of physicians and nurses were significantly more resistant to antimicrobial agents than those of personnel with minimal patient contact (p less than 0.01). Subjects had more skin damage in winter than in summer, as indicated by increased shedding of skin squames (p less than 0.05). We conclude that handwashing practices vary significantly by profession and that reporting of handwashing practices by personnel is inaccurate.

Skin replica analysis of photodamaged skin after therapy with tretinoin emollient cream

Computerized image analysis of silicone replicas, a reproducible, objective technique for measuring skin topography, was used in addition to clinical measures in two multicenter, double-blind, randomized, controlled studies of tretinoin emollient cream, a new formulation for treating photodamaged skin. Previously, the skin replica technique had been successfully used in a pilot study of tretinoin 0.05% cream by one investigator. In the present studies, subjects treated for 24 weeks with tretinoin emollient 0.05% cream consistently showed more improvement in skin topography than did vehicle-treated patients. A 0.01% concentration of tretinoin emollient cream also improved skin topography to a greater extent than the vehicle, while the lowest concentration tested (0.001%) showed little difference from vehicle. These results, reflecting a smoothening of the skin surface in tretinoin emollient cream-treated subjects, were consistent with clinical data showing greater improvement in fine wrinkling and roughness after tretinoin emollient cream therapy than after vehicle therapy. Findings from these multicenter studies confirm the value of the skin replica technique and help establish the efficacy of tretinoin emollient 0.05% cream for photodamaged skin.

Self-perceived sensory responses to soap and synthetic detergent bars correlate with clinical signs of irritation.

BACKGROUND Epidemiologic studies indicate that after using soaps and other personal care products, many consumers experience irritation. In 50% of the cases the feelings of skin dryness, itching, and stinging occur in the absence of visible signs of irritation. OBJECTIVE We sought to determine the relation between self-perceived sensory responses of panelists to cleansing products and clinical signs of irritation. METHODS A combination of exaggerated arm-washing methods was designed to induce clinical signs of irritation with psychometric techniques developed to quantify sensations. RESULTS Two studies demonstrated that panelists could reproducibly differentiate between products on the basis of the sensations they felt and that there was a significant correlation (frequently r > 0.80) between these and the observable signs. In the case of skin dryness panelists differentiated products several washing cycles before observable differences were detected. CONCLUSION Sensory evaluations of irritation yield additional information on soap and detergent irritancy beyond clinical observations and expand understanding of the irritation process.

Comparative metrology of the evaporimeter and the DermaLab® TEWL probe

Transepidermal water loss (TEWL) measurements are one of the most frequently utilized of the noninvasive bioengineering techniques. Recently, Cortex Technology (Hadsund, Denmark) introduced the DermaLab® system, which can be equipped with a TEWL probe. It is based on the vapor pressure gradient estimation method of Nilsson and, thus, is quite similar to the Servo Med evaporimeter. In this paper, we compare these two commercial instruments under identical experimental conditions using both in vitro studies with physical standards as well as in vivo studies employing human volunteers.

Clinical and Histological Effects of Glycolic Acid at Different Concentrations and pH Levels

BACKGROUND Much has been said about the effects of glycolic acid with little scientific evidence to substantiate the findings. OBJECTIVE This study reports on the clinical and histological effects of glycolic acid at pH levels 3.25, 3.80, and 4.40, and at 3.25%, 6.50%, 9.75%, and 13.00% on ichthyotic/xerotic skin. METHODS Product treatment consisted of a 2‐week washout period followed by 3 weeks of product application (BID) with a 1‐week regression period. Shave biopsies and clinical evaluations for dryness, moisturization, and transepidermal water loss were made at baseline, 1, 2, and 3 weeks of use, and at the regression period. RESULTS Clinically, ichthyotic/xerotic skin was normalized with histologic evidence of stratum corneum thinning, viable epidermal thickening, and marked increases in glycosaminoglycan and collagen content. CONCLUSION All pH levels and concentrations demonstrated significant improvement in the condition of the skin with trends implying that increasing the pH increases efficacy.

Documentation of impaired epidermal barrier in mild and moderate diaper dermatitis in vivo using noninvasive methods.

Abstract:  The presence of irritants from feces and urine with the concurrent mechanical friction and occlusion creates an environment in the diapered area that renders the skin prone to diaper dermatitis. Besides being a source of discomfort to the infant, these skin irritations pose a risk of secondary infections. In this study, we used noninvasive in vivo techniques to define measurable parameters that correlate with diaper dermatitis pathophysiology. In 35 infants (16 with mild or moderate and 19 without diaper dermatitis) we compared skin of diapered areas afflicted with diaper dermatitis to lesion‐free diapered sites and to skin outside the diapered area (thigh). Our findings show significantly elevated cutaneous erythema, pH, and hydration, with significantly compromised water barrier function in involved areas compared to nonlesional sites both within and outside the diapered area. Furthermore, skin pH in nonlesional diapered skin for the diaper dermatitis cohort was significantly higher compared to the nondiapered sites. These observations are consistent with the current understanding of pathological skin changes in diaper dermatitis. In this study, we demonstrate that noninvasive methods can document relevant parameters to diaper dermatitis in vivo.