正常人皮肤表面酸碱度的研究

皮肤是人类机体的重要组成部分．皮肤表面的酸碱度不仅是皮肤的生理指标．同时也反映了整个机体的状态。迄今为止,关于正常人皮肤表面pH值的报道不尽相同。据报道,婴儿出生时,皮肤表而的pH较高。数天后则逐渐降低。Wilhelm等曾对29例成人皮肤表面的pH进行了研究,结果发现,皮肤表而的pH囚皮肤解剖部位的不同而不同：老年人的前额和踝部皮肤表而的pH值高于年轻者。Zlotogorski的研究也证实了Wilhelm等的结果．但是也有报道,皮肤表面的pH因性别的差异而不同。这种差异性有多种因素,可能与研究组别的大小和分组的条件等有关。关于我国正常人皮肤表面pH的研究报道较少,笔者根据人体生长发育期的生理特点进行年龄分组;根据皮肤的生理特点进行部位分组。对我国正常人不同年龄、不同性别和不同部位的皮肤pH进行检测,为临床工作提供参考。[第一段]     

麻风患者愈后表皮某些生理功能障碍研究

目的：了解麻风愈后者其原受累及部位是否存在角质层生理功能障碍。方法：利用多功能皮肤生理仪对麻风患者痊愈后前臂原皮损处角质层含水量、酸碱度、透过皮肤水分丢失率及屏障功能的恢复速度进行测量。结果：与正常对照组相比,麻风愈后者原皮损处角质层含水量明显降低（P〈0．002）,以瘤型麻风患者降低幅度最大;皮肤表面的pH明显增高（P〈0．0001）,界线类偏结核型患者pH改变不甚明显;麻风愈后者原皮损处的基础表皮通透屏障功能好于正常人,以界线类偏瘤型患者水分丢失量降低最明显：麻风愈后者原皮损处表皮通透屏障功能的恢复速度无明显改变。结论：麻风患者痊愈后仍然有角质层生理功能障碍。     

皮肤表面酸碱度及其测定方法

皮肤表面pH值在维持正常的皮肤生理屏障功能、参与角质层细胞代谢酶的活性调节、保持皮肤微生态平衡和正常的皮肤感觉上发挥重要的作用。许多因素参与并影响皮肤表面pH值的形成，皮肤pH值测定方法的改进为临床皮肤生理、病理的研究奠定了基础。     

皮肤屏障研究方法的新进展

皮肤屏障为化学物经皮吸收的限速层,对维持机体内环境的稳定及抵御外环境的有害因素,有着重要的生理功能。深入研究皮肤屏障生理功能的首要任务就是建立科学有效的研究方法。本文从皮肤屏障的功能和结构两方面,对近年来应用于该领域研究方法的新进展作一概述。     

不同原因导致敏感性皮肤的皮肤生理功能测试及临床意义

目的:探讨痤疮、激素依赖性皮炎、特应性皮炎和干燥性湿疹等不同原因导致敏感性皮肤的皮肤生理功能特点,指导敏感性皮肤的护理和治疗.方法:选取各种原因导致的敏感性皮肤受试者154名,均为女性.运用无创性皮肤生理功能测试仪测量受试者的皮肤皮脂含量、角质层含水量和经表皮水分丢失(TEWL).结果:与单纯敏感性皮肤比较,痤疮组皮脂含量较高(P＜0.05),激素依赖性皮炎组TEWL值较高(P＜0.05),特应性皮炎和干燥性湿疹组皮脂含量、角质层含水量较低,而TEWL值较高(P＜0.05),其余参数比较差异无统计学意义;与痤疮导致的敏感性皮肤比较,激素依赖性皮炎组皮脂含量较低(P＜0.05),TEWL值较高(P＜0.05),特应性皮炎和干燥性湿疹组皮脂含量、角质层含水量较低(P＜0.05),而TEWL值较高(P＜0.05),其余参数比较差异无统计学意义;与激素依赖性皮炎导致的敏感性皮肤比较.特应性皮炎和干燥性湿疹组皮脂含量较低(P＜0.05),其余参数比较差异无统计学意义.结论:不同原因导致敏感性皮肤的皮肤屏障功能状态不完全一致,应根据不同病因对敏感性皮肤进行治疗和护理.     

主观皮肤类型与皮肤屏障功能的关系

目的:比较不同主观皮肤类型(油性、中性和干性皮肤)屏障功能指标的差异。方法:利用无创性方法对自评为油性、中性和干性皮肤的20~25岁北京城市女性(各30例)进行皮脂分泌率(SER)、角质层含水量、p H值和经皮肤水分丢失(TEWL)值的检测,并采用胶带连续粘脱后监测TEWL值变化的方法评价角质层完整性,采用角质层取样蛋白定量的方法评价角质层黏合力和丝氨酸蛋白酶活性。结果:主观皮肤类型为中性皮肤者具有最佳的屏障功能;干性皮肤和油性皮肤者面颊部的屏障功能均有不同程度的受损,表现为TEWL值明显升高、p H值升高、丝氨酸蛋白酶活性增加;但二者也有区别,油性皮肤者角质层完整性下降更明显,而干性皮肤主要是角质层黏合力明显减弱。结论:自评为油性和干性皮肤者与中性皮肤者相比,屏障功能均存在一定程度的缺陷,油性皮肤与干性皮肤均具有不同特点,且与其屏障受损的机制不同有关。     

人工皮肤在紫外线对皮肤作用中的研究进展

人工皮肤作为人体皮肤形态及功能的类似物,成为研究紫外线对人体皮肤作用的新型体外模型.近5年来,国内外在光生物学领域主要用其研究皮肤光损伤的形态学、分子机制及开发防护及修复光损伤制剂.同时结构更完善的皮肤模型在该研究领域的引进,为组织工程化皮肤在紫外线皮肤损伤的基础及临床研究提供新思路.     

皮肤保湿功能与保湿剂的应用

保湿剂是人们日常皮肤护理产品中的一个重要部分，用以保持角质层的水分，维持皮肤弹性，促进皮肤屏障功能的修复，加入特殊成分的保湿剂还有美白、抗老化等作用。在皮肤科临床工作中，保湿剂有良好的治疗与辅助治疗作用，可建议患者选用合适产品，不良反应亦需注意。     

皮肤表面脂质的测定

该文归纳了近20年来用于测定皮肤表面脂质的各种方法。从最早的溶剂提取法到技术上先进的皮脂仪测定法,并对各种方法的设计原理和具体操作,逐一作了介绍。通过各种方法之间的比较,对每一种方法的优、缺点进行了评价,并举例说明了各种方法的实际应用以及在科研工作中所起的作用。     

三种波长发光二极管光对光老化皮肤的作用研究

【摘要】 目的 探讨并比较530 nm、630 nm以及850 nm发光二极管（LED）光对光老化皮肤的作用。 方法 选择14例皮肤光老化受试者,随机于其一侧前臂伸侧三个区域,分别给予530、630及850 nm LED光照射,每周3次,共12次。对照射部位皮肤进行皮肤镜检查,并比较照射前、照射第2、4和6周皮肤角质层含水量、经皮水分丢失量（TEWL）以及反映皮肤颜色的皮肤亮度（L*值）和皮肤黑素指数（MI值）的变化。同时,随机选择5例、5例、4例受试者在试验前和试验第6周分别取530、630及850 nm LED光照射皮肤进行组织病理检查。 结果 经12次630、850 nm LED光照射后,经皮肤镜检查,分别有10例、7例受试者皮肤纹理变浅,色素沉着减少;7例受试者530 nm LED光照射部位皮肤纹理加深,色素沉着增加。经630和850 nm LED光照射后,14例受试者皮肤角质层含水量均明显升高（6周时分别为37.9 ± 7.7和34.5 ± 7.1 au,照射前分别为33.1 ± 6.1和32.0 ± 7.0 au,照射前后比较,均P < 0.05）,TEWL值均明显降低（6周时分别为9.8 ± 2.5和10.9 ± 2.5 g·m-2·h-1,照射前分别为14.0 ± 1.8和14.2 ± 2.6 g·m-2·h-1,照射前后比较,均P < 0.05）,L*值与MI值均未发现明显改变（P > 0.05）。530 nm组皮肤角质层含水量及TEWL值较照射前差异均无统计学意义（P > 0.05）,L*值显著降低（P < 0.05）,MI值明显增高（P < 0.05）。组织病理检查显示,照射前真皮具有典型的光化性胶原纤维、弹性纤维变性损害,照射后3组均出现新生胶原纤维、弹性纤维,排列较照射前整齐致密。 结论 630和850 nm LED光均可以改善光老化皮肤外观、屏障功能,促进胶原纤维和弹性纤维增生和重排,530 nm LED光会增加皮肤色素沉着。     

Effects of skin surface temperature on epidermal permeability barrier homeostasis

Members of the transient receptor potential (TRP) family are temperature sensors, and TRPV1, V3, and V4 are expressed in epidermal keratinocytes. To evaluate the influence of these receptors on epidermal permeability barrier homeostasis, we kept both hairless mouse skin and human skin at various temperatures immediately after tape stripping. At temperatures from 36 to 40 degrees C, barrier recovery was accelerated in both cases compared with the area at 34 degrees C. At 34 or 42 degrees C, barrier recovery was delayed compared with the un-occluded area. 4Alpha-phorbol 12,13-didecanone, an activator of TRPV4, accelerated barrier recovery, whereas ruthenium red, a blocker of TRPV4, delayed barrier recovery. Capsaicin, an activator of TRPV1, delayed barrier recovery, whereas capsazepin, an antagonist of TRPV1, blocked this delay. 2-Aminoethoxydiphenyl borate and camphor, TRPV3 activators, did not affect the barrier recovery rate. As TRPV4 is activated at about 35 degrees C and above, whereas TRPV1 is activated at about 42 degrees C and above, these results suggest that both TRPV1 and TRPV4 play important roles in skin permeability barrier homeostasis. Previous reports suggest the existence of a water flux sensor in the epidermis, and as TRPV4 is known to be activated by osmotic pressure, our results indicate that it might be this sensor.     

不同pH值的人工合成尿液对皮肤表面pH值的影响

目的 观察不同pH值的人工合成尿液对皮肤表面pH值的影响。方法 分别应用pH 2.0，3.5，5.0，6.5，8.0和10.0的人工合成尿液、蒸馏水和0.25%十二烷基硫酸钠水溶液对敏感性皮肤和正常皮肤行4 h，20 h，24 h三个阶段的封闭型斑贴试验，应用临床评估、皮肤表面pH值和TEWL值来评判皮肤反应。结果 敏感性皮肤和正常皮肤对各种溶液的反应相似。两种pH仪测量皮肤表面pH值排列顺序与原溶液的pH值顺序相同。不同pH值的人工合成尿液改变了皮肤表面pH值，而且这种改变在斑贴去除后24 h仍然存在。各人工合成尿液的TEWL值均不高于蒸馏水。只有72 h pH 6.5，8.0 和10.0的人工合成尿液的临床反应高于蒸馏水。结论 不同pH值的人工合成尿液改变皮肤表面pH值，pH 2.0 ~ pH 10.0的人工合成尿液对人体皮肤的安全性与蒸馏水相似。     

Distribution of skin surface pH on the forehead and cheek of adults

Summary The skin surface pH on the forehead and cheek of 574 men and women aged 18–95 was measured. No differences were found between men and women regarding forehead and cheek pH distribution. The group over the age of 80 showed higher pH values on both the forehead and the cheek. In 89% of the subjects measured, the skin surface pH on the cheek was higher than that on the forehead. The central 90%, i.e., the representative range, for the population below the age of 80 is between 4.0–5.5 on the forehead and between 4.2–5.9 on the cheek.Originally presented in part during the 6th International Symposium on Bioengineering and Skin 27–28 June, 1986, Liège, Belgium     

Females have lower skin surface pH than men

Background/aims: It is of great interest to describe the many functions and properties of the skin in order to better understand reactions that result in different skin abnormalities, as a prerequisite in the development of skin products and topical medicines. Skin surface pH is considered a critical parameter of skin wellbeing and is typically studied on the forearm skin. Despite many previous investigations, this is an extensive field that still needs a great deal of research. The aim of our study was to investigate gender related differences, differences between right and left arms, anatomical variation and daytime variation in skin surface pH.
Methods: Skin surface pH was measured on the flexor surface of the forearm on eleven healthy volunteers (6 men and 5 women). A Mettler Toledo pH meter (pH meter 1140) was used. The subjects were measured once every hour from 8 a.m. to 3 p.m. in five areas from the elbow to the wrist. In each of the five areas, three measurements were performed next to each other, and the mean of these was used in subsequent calculations.
Results: A statistically significant difference in skin pH between men (mean pH=5.80) and women (mean pH=5.54) was found, with women being more acidic than men ( P <0.01). No difference between right and left arm was found. In men, the area closest to the wrist had significantly lower pH values compared with the proximal sites. This was not the case in women. Skin surface pH decreased during normal working hours in both genders.
Conclusion: Spontaneous skin surface pH was found to be significantly lower in women, as compared to men – albeit, the difference was small and of unknown relevance. Nevertheless, comparative studies on skin surface pH should be balanced with respect to gender. There appeared to be no right/left difference and no systematic change during the working day. Also, measurements should not be conducted close to the wrist.