Background/aims: Keratolytics are agents used for a very long period of time to improve various skin disorders such as acne, hyperkeratoses, ichtyose etc. Very little is known about their mechanism of action on healthy skin. On man, the chronic application of a cosmetic cream containing a lipophilic derivative of Salicyclic acid (LSA) markedly improves the aspect and texture of the skin. Different methods were used to investigate the mechanisms of action of this new compound, compared to salicyclic acid. Methods: Both non‐invasive and histologic methods were used on the dorsal forearm of human volunteers treated with the products. Concerning the non‐invasive methods, TEWL, silflo replica and confocal microscopy were used. On shave biopsies, various histometric parameters were measured by image analysis after different staining. The use of antibody MIB‐1 reacting with the proliferating nuclear antigen Ki 67 allows one to measure the epidermis proliferation index. Results: Compared to the excipient alone, presence of LSA 1% improves smoothness and firmness of the skin. The appearance in terms of clearness and healthy complexion is also improved. The thickening of all the living epidermis layers is obtained by both histometric measurement and confocal microscopy. This acanthosis is only recorded on the LSA‐treated zones. The Ki 67 labelling study shows that LSA significantly increases the skin proliferation index. Conclusions: Salicylic acid, and more markedly its lipophilic derivative (LSA), appear to have a significative effect on the renewal of the living epidermis. This probably explains the cosmetic improvement of the skin obtained after a 1‐month treatment with a cream containing this new molecule.

The optical sectioning property of the confocal microscope offers a breakthrough from the classic observation of the hair in a scanning electron microscope (SEM). Confocal microscopy requires minimal sampling preparation, and the hair can be observed in its natural environment with less damage than by other microscopic methods such as SEM. While used in the reflection mode, the true morphology of the cuticle and the various exogenous deposits at the surface can be identified and quantified. This relatively noninvasive, nondestructive technique is routinely used by us to monitor the efficiency of cleansing shampoos, to assess the homogeneity of layering polymers, and to evaluate the changes they induce in the optical properties of the hair surface in terms of opacity, transparency, and brilliancy. A second important field of investigation uses the fluorescence channel which reveals the internal structure of the hair. Fluorescent probes (rhodamine and its derivatives) demonstrate the routes of penetration and outline the geometry of cortical cells and of the medulla according to their lipophilic or hydrophilic properties. A volume rendering of a hair cylinder provides a better understanding of the interrelationships between cuticle cells, cortical cells, and the medullar channel. This recent technology is becoming an invaluable tool for the cosmetic assessment of the hair.

To understand the biochemical abnormalities that underlie the reduced desquamation observed in dry skin, we analyzed corneodesmosome degradation in normal and winter xerosis skin. Western blotting of total proteins from corneocytes obtained by varnish-strippings from the legs of 56 volunteers with normal (26) or xerotic (30) skin was performed using antibodies specific for (corneo)desmosome proteins. In the whole population, the amounts of desmoglein 1 and plakoglobin were found to be correlated, but were not related to the amounts of corneodesmosin. This suggests simultaneous proteolysis for the former proteins differing from that of corneodesmosin. Neither entire desmoplakins nor any proteolysis-derived fragments were detected. The amounts of corneodesmosin, desmoglein 1, and plakoglobin detected were found to be significantly higher in xerotic compared with normal skin extracts. Conventional and freeze-fracture electron microscopy showed the absence of nonperipheral corneodesmosomes in the upper stratum corneum of normal skin but the presence of a significant number of these structures in the same layer of winter xerosis skin. These results provide a more precise description of the proteolysis of corneodesmosome components in the upper cornified layer of the epidermis. They support previous studies demonstrating the importance of corneodesmosome degradation in desquamation and reveal that the nonperipheral corneodesmosomes, which are totally degraded during maturation of the stratum corneum in normal skin, persist in winter xerosis, probably leading to abnormal desquamation.

A new confocal prototype dedicated to the exploration of in vivo human skin has been constructed around a laser confocal module (Oz Noran, Inc.) and a skin contact device, assuring perfect stability of skin images. The power of the Argon/Krypton laser source has been limited to 2mW to secure safety, and the laser provides three visible wavelengths: 488, 568, and 647 nm. Optical sections were digitized at video rate, providing easy and rapid measurements of the thickness of epidermal layers and time-resolved information. Unexpected details of the epidermis were recorded with the blue laser line. Melanin provided strong reflection of the basal keratinocytes instead of the absorption expected. The 3D reconstruction of the melanin cap in basal keratinocytes confirmed the behavior of melanosomes acting as myriads of nanomirrors that reflected light. Confocal images of the posterior aspect of the forearm were recorded before sun exposure and then for one month after exposure. There was a 25% increase in the thickness of the stratum corneum. Bright inclusions into the dark nucleus of numerous spinous cells were interpreted as local condensation of chromatin. Numerous bright intercellular filaments were attributed to melanosomes filling up dendrites of melanocytes. A striking observation concerned the lack of melanosome caps in basal keratinocytes. In vivo confocal microscopy affords new insight to the role of melanin and its gradual migration after sun exposure.

The ultrastructural study of the intercellular spaces of the human stratum corneum was based on transmission electron microscopy of thin vertical sections and freeze-fracture replicas, field emission scanning electron microscopy and immunofluorescence confocal laser scanning microscopy. The maturation of the corneosomes and their enzymatic degradation could be depicted at strategic interfaces. These sharp and rapid metamorphoses are now relatively well understood from a morphological point of view. But morphology raises a lot of unsolved physiological problems.

The purpose of this in vivo study was to investigate, non-invasively on human subjects, xerotic skin and its physiological evolution over time, compared to normal skin. Two groups of 17 female subjects were studied during the winter season, one made up of subjects with normal skin and the other subjects with xerotic skin. A clinical assessment and biometrological measurements of hydration and transepidermal water loss (TEWL) were performed on the same area of the external antero-lateral surface of the leg at the start of the study then after three weeks. At the end of the study, the ultrastructure of stratum corneum samples taken from the same area was examined by transmission electron microscopy. Subjects with xerotic skin were selected according to their impaired cutaneous barrier function, reflected in a TEWL higher than 12 g/m ; 2/h. Compared to normal subjects, they presented a hydration level more than 25% lower. After an interval of 21 days, no significant change in the hydration level or clinical appearance of the xerotic skin was observed. In contrast, the TEWL had decreased significantly (D _ 21- D _ 0=-3.6 g/m ; 2/h; p < 0.001) but still stayed higher than normal values. Changes in the ultrastructure of the stratum corneum were also observed in the subjects with xerotic skin. Unlike normal skin, corneosomes could be detected right up to the surface layers, accompanied by intercellular lipids in an amorphous form. These observations confirm the important roles played by both corneosomes and lipid organization in the cohesion/desquamation processes. In the subjects with normal skin, the hydration level and barrier function remained unchanged during the three week study but an onset of skin dryness was observed, the mean clinical score increasing by +1.3 (p = 0.01). These results confirm that there is no direct relationship between TEWL and the severity of skin dryness. It appears that a clinical evaluation is more sensitive than biometrological measurement for describing early state of cutaneous dryness. This study highlights the importance of a regular cosmetic or dermopharmaceutical treatment during the winter to prevent xerosis apparition on legs.

A new generation of confocal laser microscope, designed to image the human skin in vivo, improves the resolution, contrast and spectroscopic facilities as compared to the previous Tandem Scanning Microscope (TSM) prototype. The new device has been built with a Oz module (Noran) equipped with the skin contact device, assuming a perfect stability of skin images in the horizontal plane. The Z displacement of the objective lens, mounted directly on the Ch module, is assumed by a piezo motor with a course of 350 mu m. Moreover, the Ch module has been suspended on articulated arms to reach any part of the human body. The power of the Argon/Krypton laser source has been limited to 2 mW to secure safety and provides three visible wavelength : 488, 568 and 647 nm. The facility of instantly checking wavelength during in depth exploration of the skin optimizes the resolution and contrast of images as compared with the white light used in the TSM. Consequently, better image quality of the epidermis is obtained in the blue region with unexpected details of corneocytes and keratinocytes. The papillary dermis comprising the vascular network is advantageously observed with the red light. The fluorescence channel detector gives additional information on the penetration of fluorescent probes through the skin barrier. Optical sections are digitized (512 x 480 x 8 bit) at video rate, providing easy and fast measurements of the thickness of epidermal layers. The Silicon Graphics workstation generates a transparent volume of living human skin in less than 5 minutes. This powerful and convivial new design for imaging the in vivo human skin opens up new promises in skin research and in vivo skin pharmacology.

Research Articles| August 16 2010 Effect of Thiol Compounds on Phagocytosis Subject Area: Further Areas , Oncology , Pathology and Cell Biology Józef Lisowski; Józef Lisowski (From the Ludwik Hirszfeld’s Institute of Immunology and Experimental Therapy in Wrocław, Poland.) Search for other works by this author on: This Site PubMed Google Scholar Zbigniew Wieczorek; Zbigniew Wieczorek (From the Ludwik Hirszfeld’s Institute of Immunology and Experimental Therapy in Wrocław, Poland.) Search for other works by this author on: This Site PubMed Google Scholar Adam Skurski Adam Skurski (From the Ludwik Hirszfeld’s Institute of Immunology and Experimental Therapy in Wrocław, Poland.) Search for other works by this author on: This Site PubMed Google Scholar Schweizerische Zeitschrift für allgemeine Pathologie und Bakteriologie (1958) 21 (6): 1096–1105. https://doi.org/10.1159/000160570 Article history Published Online: August 16 2010 Content Tools Views Icon Views Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Icon Share Facebook Twitter LinkedIn Email Tools Icon Tools Get Permissions Cite Icon Cite Search Site Citation Józef Lisowski, Zbigniew Wieczorek, Adam Skurski; Effect of Thiol Compounds on Phagocytosis. Schweizerische Zeitschrift für allgemeine Pathologie und Bakteriologie 1 June 1958; 21 (6): 1096–1105. https://doi.org/10.1159/000160570 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentAll JournalsSchweizerische Zeitschrift für allgemeine Pathologie und Bakteriologie Search Advanced Search Article PDF first page preview Close Modal This content is only available via PDF. 1958Copyright / Drug Dosage / DisclaimerCopyright: All rights reserved. No part of this publication may be translated into other languages, reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, microcopying, or by any information storage and retrieval system, without permission in writing from the publisher.Drug Dosage: The authors and the publisher have exerted every effort to ensure that drug selection and dosage set forth in this text are in accord with current recommendations and practice at the time of publication. However, in view of ongoing research, changes in government regulations, and the constant flow of information relating to drug therapy and drug reactions, the reader is urged to check the package insert for each drug for any changes in indications and dosage and for added warnings and precautions. This is particularly important when the recommended agent is a new and/or infrequently employed drug.Disclaimer: The statements, opinions and data contained in this publication are solely those of the individual authors and contributors and not of the publishers and the editor(s). The appearance of advertisements or/and product references in the publication is not a warranty, endorsement, or approval of the products or services advertised or of their effectiveness, quality or safety. The publisher and the editor(s) disclaim responsibility for any injury to persons or property resulting from any ideas, methods, instructions or products referred to in the content or advertisements. You do not currently have access to this content.

A new noninvasive microscopic technique of three‐dimensional optical biopsy from in vivo human skin based on real‐time confocal microscopy and computer reconstruction is demonstrated. A tandem scanning confocal microscope is a prototype of a mobile, flexible design for the in‐depth microscopic exploration of the skin on the human body. The various skin layers were observed in real‐time, at the subcellular level down to a depth of 200 μm with a vertical resolution of 2 μm. Rapid video recording of the Z ‐series through the ventral aspect of the forearm avoided shifts caused by subject movement and blood flow pulsations. Two video frames were averaged, and the average was digitized, providing a stack of 64 optical sections in 1‐μm vertical steps. Three‐dimensional reconstructions of in vivo human skin were obtained with sets of orthogonal slices, and slices at arbitrary planes through a volume containing the stack of slices. This method clearly shows the spatial relationships between the different cell layers. The use of orthogonal cutting planes is preferred because of its analogy with classical vertical sections of histopathology. Linear structures (surface lines) within the stratum corneum are described and their global orientations were determined by the use of Fourier transform analysis. En face optical sections constitute unusual views of this tissue, since typical pathohistological studies are based on sagittal (vertical) slices. The noninvasive optical microscopic technique provides a three‐dimensional optical biopsy of in vivo human skin.

We have improved the optical interferometric imaging technique that was recently used to measure local organic material concentrations in quasicylindrical cells. This allowed similar measurements for cells of arbitrary shape. The setup was used to measure the thickness of skin corneocytes.

In-depth exploration of cellular structures in living human skin in situ is possible with the tandem scanning microscope (TSM). However, the rigid design of the microscope limited observations to the arms, hands, and fingers. A mobile version allowing the investigation of any parts of the body has been designed. The head containing the Nipkow disk and the optical path were the only part saved from the original TSM. This prototype can be used to observe, in real time, the different skin structures down to a depth of 200 microns and to measure the thickness of the different layers with micron precision level. The hydration of the stratum corneum (SC) could be assessed. For example, lengthy immersion of the hand in water led to an increase in SC thickness without affecting that of the living epidermis. Occlusive patch tests also showed that water and, even more so. propylene glycol, led to transient swelling of the SC. In dermatology, the example of psoriasis illustrated the value of the TSM for describing, measuring, and assessing pathologic skin changes. The availability of this noninvasive method for observing changes with time in a given skin site should prove useful for monitoring treatment efficacy. This tool opens up new insight for the investigation of cutaneous pathophysiology.

INTRODUCTION:The microbiological identification of onychomycosis may be uncertain as some fungi growing in culture from this material are not necessarily pathogen and invasive. Conversely, the negativity of a culture is not rare even when fungi are seen by microscopy.MATERIALS AND METHODS:We compared the information brought by standard histological examination, immunohistochemistry and in vivo confocal microscopy.RESULTS:The histological examination of nails is of importance in this pathology. We present a laboratory technique that proves to be easy and rapid. We report diagnostic criteria allowing the distinction between dermatophytes, yeasts and non-dermatophyte molds. The standard microscopic examination may further be improved by immunohistochemistry using some antibodies to fungi. In vivo confocal microscopy is a technique for the future. The dermatologist will be able to see fungi in the nail at the clinical examination, without any sampling or peculiar preparation.CONCLUSION:The histological examination is a routine technique useful for defining the nature and localization of fungi in the nail plate. Immunohistochemistry applied to onychomycosis is an experimental approach bringing prominent informations about the identification of fungi. In vivo confocal microscopy is a door opened to the future.