Quantification of the skin's topography by skin profilometry

A method of skin profilometry is presented. The data generated using this method are used to (a) uncover sources of variation in skin profilometry, (b) provide information regarding the choice of roughness parameters best suited for characterizing the skin's topography, and (c) determine if skin profilometry is a valuable tool for quantitatively assessing changes in the skin's surface pattern.
The data show the roughness parameter values to be dependent on the orientation of the tracings with regard to the major grooves and ridges present in the surface patterns. Large variabilities of roughness parameter values obtained for multiple scans within small areas of replicas are indicative of the nonhomogeneity of the skin's surface. The number of peaks, mean peak size, mean depth of roughness, depth of smoothness, and residual profile length appear to be the most utile roughness parameters for quantifying changes in the skin's topography. The ability of skin profilometry to detect subtle changes in the skin's surface pattern due to hydration indicates the method is a sensitive means of quantifying the skin's topography.
Quantification de la topographie de la pedu par la profilométrie de la pedu     

德瑞绵羊皮和山羊皮制革技术

本文详细介绍了德国德瑞公司在制革技术交流会上进行绵羊皮和山羊皮制革工艺试验的情况。     

碱性脂肪酶在驴马皮制革中的应用研究

对脂肪酶在驴马皮制革过程中的应用进行了研究。结果表明:使用脂肪酶不仅能降低制革污染,同时还能有效提高革坯的均匀度和强度,使蓝革粒面平细、洁净。     

Influence of skin cleansing preparation acidity on skin surface properties

Two long-term trials were conducted each over eight weeks to compare the effect of the regular application of skin cleansing preparations of pH 5.5 and pH 8.5 and pH 5.5 and pH 7.0 respectively on the surface pH, roughness and transepidermal water loss (TEWL) of normal human forehead and forearm skin. Both trials were based on a cross-over design: five healthy volunteers started with a pH 5.5 preparation and switched to the other after four weeks, five additional volunteers used the preparations in the opposite order. While the skin surface pH was markedly lower in those individuals using the pH 5.5 preparation at each examination, as compared to those using the pH 8.5 or pH 7.0 preparation, no such difference could be established with respect to skin roughness and TEWL. Hence the skin irritancy of a cleansing preparation does not seem to be linked to its pH within the pH ranges tested.     

A review of ageing and an examination of clinical methods in the assessment of ageing skin. Part 2: Clinical perspectives and clinical methods in the evaluation of ageing skin

With the advancement of skin research, today's consumer has increased access to technological information about ageing skin and hair care products. As a result, there is a rapidly increasing demand for proof of efficacy of these products. Recognizing these demands has led to the development and validation of many clinical methods to measure and quantify ageing skin and the effects of anti-ageing treatments. Many of the current testing methods used to research and evaluate anti-ageing product claim to employ sophisticated instruments alongside more traditional clinical methods. Intelligent use of combined clinical methods has enabled the development of technologically advanced consumer products providing enhanced efficacy and performance. Of non-invasive methods for the assessment and quantification of ageing skin, there is a plethora of tools available to the clinical researcher as defined by key clinically observed ageing parameters: skin roughness and surface texture; fine lines and wrinkles; skin pigmentation; skin colour; firmness and elasticity; hair loss; and proliferative lesions. Furthermore, many clinical procedures for the evaluation of ageing skin treatments are combined with invasive procedures, which enable added-value to claims (such as identification and alteration of biochemical markers), particularly in those cases where perception of product effect needs additional support. As discussed herein, clinical methods used in the assessment of skin ageing are many and require a disciplined approach to their use in such investigations.     

Progressive evaluation of skin irritancy of cosmetics using human volunteers

Cosmetics and toiletries should not elicit adverse reactions in use. Neither should they cause unacceptable effects if mis-used. Reliable prediction of these product attributes can be achieved by subjecting human volunteers to typical product exposure and to grossly exaggerated exposure. However, to ensure that volunteers do not sustain harmful effects there needs to be a cautiously progressive programme of testing.
There must be adequate data on record to support exposure of human skin to the test material. The first contact with human skin should be in a small area, for short duration, and be very closely observed. When the effects are well within acceptable limits the exposure can be extended. As information accumulates, the application procedure can evolve towards simulation of the intended use of the product under controlled conditions, and eventual free use in consumer tests; and also towards exaggerated use to evaluate potential irritancy, using exaggerated frequency of use, exaggerated product concentration, or occlusive cover to promote skin penetration and enhance irritancy.
Skin reactions under exaggerated exposure conditions do not necessarily mean that a product would be unacceptable under normal use conditions or when misused predictably. Therefore, appropriate standard products must be included in tests to provide relevant comparison when significant skin reaction does occur.
Data will be presented to demonstrate progressive evaluation of irritancy of cosmetics and toiletries, based on expert assessment of visible skin reactions and on analysis of spontaneous and prompted comments about subjective effects, and including appropriate attention to the ethical requirements for tests involving human volunteers.     

银狐皮毛被及皮板组织构造的研究(续)

用光学显微镜和扫描电镜观察了国产人工饲养银狐的毛被和皮板组织构造 ,测定了毛的长度、细度、密度、毛的鳞片高度和皮板厚度。提供了毛和皮板组织学图片 15幅     

Caucasian facial L* shifts may communicate anti-ageing efficacy

An ageing study was conducted to capture skin colour parameters in the CIELab system from Caucasians of both genders and all available adult ages. This study produced a linear correlation between L* and age for a Caucasian population between 20 and 59 years of age as follows: (L* value) = -0.13 × (Age in years) + 63.01. Previous studies have addressed age-related changes in skin colour. This work presents a novel consumer correlated quantitative linear model of skin brightness by which to communicate age-related changes. Two product assessment studies are also presented here, demonstrating the ability of anti-ageing products to deliver on objective and subjective improvements in skin brightness. It was determined to be possible to use the fundamental Caucasian L*-age correlation to describe product benefits in a novel quantitative and consumer-relevant fashion, through the depiction of a 'years back' calculation.     

Natural skin surface pH is on average below 5, which is beneficial for its resident flora

Variable skin pH values are being reported in literature, all in the acidic range but with a broad range from pH 4.0 to 7.0. In a multicentre study (N = 330), we have assessed the skin surface pH of the volar forearm before and after refraining from showering and cosmetic product application for 24 h. The average pH dropped from 5.12 +/- 0.56 to 4.93 +/- 0.45. On the basis of this pH drop, it is estimated that the 'natural' skin surface pH is on average 4.7, i.e. below 5. This is in line with existing literature, where a relatively large number of reports (c. 50%) actually describes pH values below 5.0; this is in contrast to the general assumption, that skin surface pH is on average between 5.0 and 6.0. Not only prior use of cosmetic products, especially soaps, have profound influence on skin surface pH, but the use of plain tap water, in Europe with a pH value generally around 8.0, will increase skin pH up to 6 h after application before returning to its 'natural' value of on average below 5.0. It is demonstrated that skin with pH values below 5.0 is in a better condition than skin with pH values above 5.0, as shown by measuring the biophysical parameters of barrier function, moisturization and scaling. The effect of pH on adhesion of resident skin microflora was also assessed; an acid skin pH (4-4.5) keeps the resident bacterial flora attached to the skin, whereas an alkaline pH (8-9) promotes the dispersal from the skin.     

鱼皮饰品革生产工艺的探讨

本文探讨了用鱼皮生产饰品革的工艺，并用该工艺生产出了丰满、柔软、强度较高的饰品革。     

The effect of smoking on skin moisture and on surface lipids

In the present retrospective study we investigated the effect of smoking on the moisture and surface lipid levels of the skin. We analysed data from the files of 576 female clients treated in a Tel-Aviv cosmetic parlour. Measurements have been conducted by the same cosmetician, by commercially available equipment, on every client receiving cosmetic treatment, regardless of the nature of the treatment.
Results demonstrated a significant difference of skin moisture in the various smoking groups: women who smoked 11–20 cigarettes per day showed significantly lower mean values than the non-smoker group, as expected. Moreover, women before or after menopause showed no significant differences in their moisture measurements.
The surface lipid variables showed no significant differences in mean over the four smoking groups.
We believe that the objective of the study was achieved, and that the results, indicating decreased skin moisture in smokers, will serve well in anti-smoking campaigns. We also believe that the present study will stimulate other investigators to conduct similar studies that will provide answers to the many questions which still remain open.     

Intrinsic and extrinsic factors in skin ageing: a review

As the proportion of the ageing population in industrialized countries continues to increase, the dermatological concerns of the aged grow in medical importance. Intrinsic structural changes occur as a natural consequence of ageing and are genetically determined. The rate of ageing is significantly different among different populations, as well as among different anatomical sites even within a single individual. The intrinsic rate of skin ageing in any individual can also be dramatically influenced by personal and environmental factors, particularly the amount of exposure to ultraviolet light. Photodamage, which considerably accelerates the visible ageing of skin, also greatly increases the risk of cutaneous neoplasms. As the population ages, dermatological focus must shift from ameliorating the cosmetic consequences of skin ageing to decreasing the genuine morbidity associated with problems of the ageing skin. A better understanding of both the intrinsic and extrinsic influences on the ageing of the skin, as well as distinguishing the retractable aspects of cutaneous ageing (primarily hormonal and lifestyle influences) from the irretractable (primarily intrinsic ageing), is crucial to this endeavour.     

银狐皮毛被及皮板组织构造的研究

用光学显微镜和扫描电镜观察了国产人工饲养银狐的毛被和皮板组织构造 ,测定了毛的长度、细度、密度、毛的鳞片高度和皮板厚度。提供了毛和皮板组织学图片 15幅。     

An in vivo assessment of the biomechanical properties of human skin modifications under the influence of cosmetic products

A new device using a torsional technique has been developed to record the biomechanical properties of the skin.
After determination of the optimal experimental conditions, effects of cosmetic products on the stratum corneum biomechanical properties are described.