Effect of methylene blue and cobaltous chloride on the alloxan-induced changes in collagen characteristics in the skin of garden lizard Calotes versicolor

In the present study the effect of two chemicals such as methylene blue and CoCl2 on the accelerated ageing of collagen in alloxan-diabetic lizards has been tested. Both methylene blue and CoCl2 have been found to accelerate the ageing of collagen in normal lizards. While methylene blue enhanced the effects of alloxan in alloxanized lizards, CoCl2 tended to reverse it. It appears that methylene blue acts as a potentiator of alloxan; CoCl2, on the contrary, showed clear anti-ageing effects.

Flash fluorometer made from off-the-shelf photographic equipment to measure tissue levels of fluorescein

A device to measure fluorescein in tissue has been constructed from standard photographic equipment--an electronic strobe and a flashmeter both covered with interference filters. The instrument works well in the light and need not touch the area being measured, an advantage over existing fluorometers. The instrument has been used to measure the amount of dye in flaps in rats, pigs, and three humans. The results revealed that the amount of dye in a freshly made flap was rarely as much as in normal skin, and skin with less than 20 percent of the dye of control areas usually sloughed, although there were exceptions. In the future the instrument will be improved, and its readings will be compared to those obtained from radioactive microspheres, the present "gold standard" of techniques to measure vascularity. The instrument can be used to estimate the blood supply to any tissue and seems to be as reliable as the dermofluorometers already on the market.

Immunological distribution of one form of insulin-like growth factor (IGF)-binding protein and IGF peptides in human fetal tissues

Insulin-like growth factors (IGFs) are expressed by, and are biologically active on, human fetal cells. The mitogenic actions of IGF-I are modulated by the 21-41 kDa class of IGF-binding proteins (IGF-BPs). Using a rabbit anti-human IGF-BP antibody raised against a highly pure 26 kDa IGF-BP derived from amniotic fluid, we have compared the cellular location of IGF-BP and IGF peptides in tissue sections from prostaglandin-induced human abortuses of 14-16 weeks of gestation. The monoclonal and polyclonal antibodies used were raised against human IGF-I, but did not distinguish between IGF-I and IGF-II. Positive staining for IGF-BP was seen in every tissue except brain, spleen and thyroid. With the exception of skin, the cellular distribution of IGF-BP was similar to that of IGF peptides. Strong immunostaining was found in hepatocytes, hepatic erythropoietic cells, pulmonary epithelium, the tubular epithelium of kidney, intestinal epithelia, the fetal adrenal cortex and cardiac and skeletal muscle fibres. In skin, IGF-BP was located throughout the dermis and in the germinal layer of the epidermis. IGF peptide in skin was restricted to the deeper dermal layers. In the tibial epiphyseal growth plate both IGF-BP and IGF peptide were located in chondrocytes throughout the proliferation and hypertrophic zones. The similarity in distribution of IGF-BP and IGF peptides in fetal tissues suggests that the latter may exist predominantly complexed to IGF-BP in or on the surfaces of cells in vivo. The distribution of IGF-BP may define the sites of biological action of IGF peptides.

Axolinin localization in the nervous tissue of squid revealed by monoclonal antibodies specific for axolinin: cellular and subcellular localization of axolinin in the squid neuron

Cellular and subcellular distributions of axolinin, the 260-kilodalton (kD) microtubule-associated glycoprotein originally purified from squid axons, in various squid tissues such as optical lobes, bundles of small nerve fibers (fin nerves), giant stellate ganglia, skin, muscle, liver, and gill, were immunologically studied using monoclonal antibodies specifically recognizing the polypeptide chain of axolinin. The following results were obtained: (1) Axolinin is confined to squid neurons and skin; (2) axolinin is localized in the axon whereas another 260-kD microtubule-associated protein, MAP B, is localized in the cell bodies; and (3) axolinin is localized mainly in the peripheral part of the axoplasm of the squid giant axon. The last result has confirmed our previous conclusion obtained using polyclonal antisera against axolinin, which contain antibodies recognizing not only axolinin-specific epitopes but also nonspecific epitopes. The physiological importance of the localization of axolinin in axons and the skin is discussed based on its possible relationship to excitability function.

Biogenic amines and active peptides in extracts of the skin of thirty-two European amphibian species

1. Extracts prepared from fresh or dried skins of 32 European amphibian species were submitted to chemical (colour reactions) and biological screening to determine the occurrence and contents of biogenic amines and peptides active on smooth muscle preparations and blood pressure. 2. Only indolealkylamines were detectable in the skins. They were represented by tryptamine, 5-hydroxytryptamine, and its N-methylated, cyclized and sulphoconjugated derivatives. 3. The peptide families identified in the extracts were as follows: bombesins (bombesin and alytesin), bradykinins (bradykinin, bradykinin 1-8, bradykinin 1-7), chemotactic peptides (RECP I, II and III), bombinins and TRH. Bombesins, bombinins and TRH (thyrotropin-releasing hormone) were isolated from skin extracts of discoglossid frogs; chemotactic peptides and again TRH from extracts of ranid frogs. 4. Further research will certainly lengthen the list of active peptides in the skin of European amphibians, as is the case with Australian, American and African amphibians.

Optimization of immunohistochemical techniques to detect extracellular matrix proteins in fixed skin specimens

Complete antigen visualization in the context of well-preserved tissue architecture is the goal of all immunohistochemical techniques. Frozen tissue section techniques achieve optimal antigen visualization but preserve tissue architecture poorly. On the other hand, formalin-fixed tissue section techniques preserve tissue architecture very well but result in antigen masking. Enzymatic digestion or salt extraction of formalin-fixed sections has been used to reestablish antigen expression. Recently acid-alcohol-fixed tissue has been used as a successful compromise between tissue architecture preservation and the visualization of cytoskeletal antigens. In an attempt to find an improved immunohistochemical process for non-cytoskeletal antigens, we compared avidin-biotin immunofluorescence staining in frozen, formalin-fixed, and acid-alcohol-fixed tissues. The fixed tissues were either untreated or treated with enzyme digestion or salt extraction. For this study, we examined healing cutaneous wounds in Yorkshire pigs with antibodies to fibronectin, laminin, von Willebrand factor VIII, and keratin. Although tissue architecture was poor, frozen sections provided the best antigen visualization and were therefore used as the standard for complete antigen expression. Formalin-fixed tissues had excellent tissue architecture, but most antigens were completely masked. Pre-treatment technique only partially overcame the antigen masking caused by formalin. In contrast, acid-alcohol fixation preserved tissue architecture almost as well as formalin and sometimes allowed complete antigen visualization; however, laminin and fibronectin were partially masked. Total recovery of the expression of these antigens could be obtained by pre-treating the acid-alcohol-fixed tissue with either hyaluronidase or 1 M NaCl. Therefore, acid-alcohol-fixed tissue appears best for extracellular matrix (ECM) protein immunostaining as well as for cytoskeletal staining. However, certain ECM antigens require hyaluronidase or 1 M NaCl treatment for optimal visualization.

Adhesion molecule mapping in normal human skin

Adhesion molecules are a rapidly growing group of cell surface receptors providing cell-cell and cell-matrix interactions. Their physiological role in tissue homeostasis as well as cellular migration and differentiation is increasingly appreciated. In the present study we have analyzed the expression pattern of most adhesion molecules of the integrin family as well as of adhesion molecules belonging to the immunoglobulin superfamily in normal human skin. We provide evidence that expression of adhesion molecules in the various cutaneous cell systems follows a constant distribution. Moreover, the physiological mononuclear infiltrate of the skin also expresses a variety of adhesion molecules enabeling these cells to migrate or to reside within the skin. Furthermore, our results indicate that intercellular adhesion molecule-1 is not a prerequisite for lymphocyte epidermotropism as frequently stated. Our data provide a rational basis to analyze changing adhesion molecule expression in inflammatory and neoplastic skin diseases.

Demonstration of intra- and extracellular localization of bullous pemphigoid antigen using cryofixation and freeze substitution for postembedding immunoelectron microscopy

Using low-temperature postembedding techniques for immunoelectron microscopy, we succeeded in demonstrating the precise localization of bullous pemphigoid antigen (BP-Ag) in normal human skin. Small pieces (less than 1 mm3) of normal adult skin were rapidly frozen in liquid propane at -190 degrees C and subjected to freeze substitution with 100% methanol at -80 degrees C. Specimens were embedded in Lowicryl K11M at -60 degrees C which was polymerized under ultraviolet radiation at -60 degrees C. Ultrathin sections were incubated with BP sera followed by rabbit anti-human IgG and colloidal-gold conjugated anti-rabbit IgG. Epidermal ultrastructure was generally well preserved: the basal cell plasma membrane and intra- and extracellular components of hemidesmosomes could be resolved. Gold particles were mainly distributed on and around the hemidesmosomes in both intra- and extracellular sites, with most of the labelling being inside the basal keratinocytes and within about 300 nm of the basal plasma membrane. No specific labelling was observed beneath melanocytes or when normal human serum was used as a control instead of BP serum. Our observations indicate that BP-Ag is localized in and around hemidesmosomes in normal human skin and that the antigen has both intracellular and extracellular domains with the major component occurring inside the cells.

Prolonged treatment with topical glucocorticoids results in an inhibition of the allergen-induced weal-and-flare response and a reduction in skin mast cell numbers and histamine content

The inhibitory effects of topical glucocorticosteroid treatment on the immediate dermal allergic reaction were studied in 10 patients in a double, randomized, placebo-controlled fashion. The aim was to study whether a prolongation of the treatment time would enhance the inhibitory effect beyond the 30-40% reduction previously reported after 1 week of treatment, and whether any changes in skin reactivity were accompanied by changes in the level of mast cells or histamine at the challenge site. Allergen and histamine skin-prick tests were performed on both forearms before the start of the study and after 2 and 4 weeks of treatment with placebo cream on one forearm and with 0.05% clobetasol-17-propionate cream on the other. Punch biopsies from the skin treated actively and with placebo were taken after 4 weeks in eight of the patients. The specimens were used for the light-microscopic evaluation of mast cell density and for the measurement of histamine and protein content. After 4 weeks of treatment we found a reduction in the allergen-induced weal (72%; P less than 0.001) and flare (62%; P less than 0.05) response. There was also a minor reduction in the histamine-induced weal (38%; P less than 0.05) but not the flare response, suggesting that the glucocorticoid treatment induced a reduced mediator release at allergen challenge. This could be partially explained by the finding of a reduction in the number of detectable skin mast cells (85%; from 0.78 to 0.11 mast cells per unit area) and in the histamine content of the skin as related to the tissue wet weight (36%; P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

The effect of supplementation with selenium and vitamin E in psoriasis

Since reduced concentrations of selenium in whole blood, plasma and white cells had previously been observed in psoriasis, 69 patients were supplemented daily with either 600 micrograms of selenium-enriched yeast, 600 micrograms of selenium-enriched yeast plus 600 IU of vitamin E or a placebo for 12 weeks. Before supplementation, the patients' mean concentrations of selenium in whole blood and plasma were reduced compared with those of matched healthy controls but their red cell glutathione peroxidase (GSH-Px) activity was normal. After 12 weeks supplementation the patients' mean whole blood, plasma and platelet selenium concentrations, platelet GSH-Px activity and plasma vitamin E concentration had risen significantly from the baseline values but their mean skin selenium concentration and red cell GSH-Px activity remained unchanged. The mean white cell selenium concentration rose only in the group receiving selenium alone. Neither supplementation regimen reduced the severity of psoriasis or produced side-effects. The increase in platelet GSH-Px activity suggests that the supplements were bioavailable and that the patients' selenium status may have been reduced prior to supplementation. The failure of the selenium content of the skin to increase may explain why the patients' psoriasis remained unchanged during supplementation.

Histochemistry of glycoconjugates in the skin of the bovine muzzle, with special reference to glandular structures

The distribution of glycoconjugates in the muzzle of young adult Holstein cows has been studied by means of selected light-microscopic histochemical methods, including lectin histochemistry. In the skin layers, strong reactions were confined to intercellular substances in between the cells of the vital epidermis, exhibiting neutral glycoconjugates mainly with alpha-D-galactosyl and N-acetyl-D-galactosaminyl residues. In the nasolabial glands, distinctly positive staining for neutral glycoproteins with various saccharide residues (alpha-D-galactose, alpha-N-acetylgalactosamine, D-galactose-beta(1----3)D-N-acetylgalactosamine, beta-D-galactose), and for smaller amounts of acidic glycoconjugates, was found in the secretory cells and the luminal secretion. The cells of the excretory duct system showed weak to moderate reactions (alpha-D-galactose, beta-D-galactose), only the collecting ducts reacted positively for acidic glycoproteins with sialyl residues. The results obtained are discussed in view of muzzle function, with special reference to the salivary nature of the secretion of bovine nasolabial glands.

Stratum corneum lipids in skin xerosis

Lipids of the stratum corneum are implicated in cohesion and desquamation of the stratum corneum as well as in the maintenance of normal barrier function. Evidence linking the intercellular lipids to such processes has mainly been derived from studies on acquired or inherited diseases of lipid metabolism manifesting abnormalities in the structure and the function of the stratum corneum. We have studied the composition of stratum corneum lipids in clinically normal individuals with typical xerosis or 'winter dry skin' in order to establish if the lipid composition differs from that of normal individuals, showing no signs of xerosis. The amount of total stratum corneum lipids was not related to xerosis (22.0 +/- 1.8 micrograms/cm2 for normal skin, and 26.3 +/- 2.9 micrograms/cm2 for severe xerosis), and no correlation was evident between polar lipids, cholesterol sulfate (2.8 +/- 0.5% for normal skin, and 1.6 +/- 0.2% for severe xerosis), or ceramides types I-VI, and dry skin. It therefore appears that dramatic changes in stratum corneum lipids are not detectable in normal 'winter dry' skin. However, a decreased proportion of neutral lipids (sterol esters, triglycerides), coupled to increased amounts of free fatty acids, were found associated to the severity of dry skin. Apart from a decline in the sebaceous function and in esterases activity, winter dry skin does not appear to be associated to dramatic changes in polar stratum corneum lipids.

Amino acid sequence of thymopoietin isolated from skin

The isolation of thymopoietin-reactive material in fetal bovine skin was monitored by means of a radioimmunoassay to thymopoietin. The amino acid sequence of this material was determined to be identical with that of thymopoietin isolated from the thymus. Experimental evidence suggests that thymopoietin in the circulation derives from the thymus and not from the skin, suggesting that the thymopoietin in keratinocytes has a local function, either apocrine and/or immunoregulatory.

Characterization of type I collagen from the skin of blue grenadier (Macruronus novaezelandiae)

The skin collagen of a fish, blue grenadier (Macruronus novaezelandiae), has been purified and characterized. The fish skin was readily soluble in dilute acetic acid, with no pepsin treatment needed. The collagen was purified by salt precipitation. Skin samples from fish of various ages showed that even in the oldest sample, more than 8 years of age, the collagen was still readily acid soluble. The purified collagen had a melting temperature of 22 degrees C; the shrinkage temperature for the skin was 48 degrees C. Its tissue distribution, examined by immunohistology, and its chemical properties indicated a close homology to mammalian type I collagen. However, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) showed that three distinct alpha-chains were present. These were purified by ion-exchange chromatography on CM-cellulose and by gel permeation chromatography on Superose 6. The three purified alpha-chain fractions were examined by amino acid analysis and by SDS-PAGE of their cyanogen bromide fragments. These data indicated that the additional chain was genetically distinct, and most closely related to the alpha 1-chain, from which it was poorly resolved on SDS-PAGE.

Induction of tenascin in healing wounds

The distribution of the extracellular matrix glycoprotein, tenascin, in normal skin and healing skin wounds in rats, has been investigated by immunohistochemistry. In normal skin, tenascin was sparsely distributed, predominantly in association with basement membranes. In wounds, there was a marked increase in the expression of tenascin at the wound edge in all levels of the skin. There was also particularly strong tenascin staining at the dermal-epidermal junction beneath migrating, proliferating epidermis. Tenascin was present throughout the matrix of the granulation tissue, which filled full-thickness wounds, but was not detectable in the scar after wound contraction was complete. The distribution of tenascin was spatially and temporally different from that of fibronectin, and tenascin appeared before laminin beneath migrating epidermis. Tenascin was not entirely codistributed with myofibroblasts, the contractile wound fibroblasts. In EM studies of wounds, tenascin was localized in the basal lamina at the dermal-epidermal junction, as well as in the extracellular matrix of the adjacent dermal stroma, where it was either distributed homogeneously or bound to the surface of collagen fibers. In cultured skin explants, in which epidermis migrated over the cut edge of the dermis, tenascin, but not fibronectin, appeared in the dermis underlying the migrating epithelium. This demonstrates that migrating, proliferating epidermis induces the production of tenascin. The results presented here suggest that tenascin is important in wound healing and is subject to quite different regulatory mechanisms than is fibronectin.

Post-embedding methods for immunolocalization of elastin and related components in tissues

Elastic tissue is composed of amorphous-appearing elastin and 12-nm diameter microfibrils, one component of which has recently been isolated and characterized as the 31 KD microfibril-associated glycoprotein MAGP. Monospecific antibodies to each of these components have been developed in this laboratory. The parameters that determine optimal localization of colloidal gold probes for post-embedding immunolabeling of elastic tissue components have been systematically studied in a variety of normal and developing tissues in mammals and birds. Protein A-gold probes stabilized with dextran have been shown to provide complexes that remain stable after more than 2 years. Conditions have been defined that permit precise localization within the extracellular matrix of antibodies to MAGP and to elastin, singly and together. Best results were obtained with acrylic resins (Lowicryl K4M or LR White). Fixation in glutaraldehyde or other aldehydic fixatives, with or without osmium, did not affect the immunostaining of elastic tissue with affinity-purified antibodies to tropoelastin, or to anti-[alpha-elastin] or anti-[alkali-insoluble elastin]. Immunostaining with the anti-MAGP antibody was less robust and was possible in tissues which had been fixed only lightly before embedding in Lowicryl K4M or LR White. This staining was enhanced by metaperiodate oxidation of the sections as well as by reduction of the tissues with sodium borohydride en bloc, followed by hyaluronidase digestion of the sections. The effects on immunostaining of a range of enzyme digestions have also been examined. Conditions have thus been defined that make possible detailed study of the relationship between elastic tissue, elastin-associated microfibrils, and other microfibrillar structures in normal and abnormal tissues during development and aging.

The expression of congenital ichthyosiform erythroderma in second trimester fetuses of the same family: morphologic and biochemical studies

The first born offspring of first-cousin parents was affected with a keratinization disorder thought to be nonbullous congenital ichthyosiform erythroderma (CIE). In each of three subsequent pregnancies, the parents elected to have prenatal diagnosis based on evaluation of fetal skin biopsies. The epidermis of fetus 1 was identical to normal 21-wk estimated gestation age (EGA) fetal epidermis, but because keratinization begins normally around 24 wk EGA, the procedure was repeated 4 wk later. A thin epidermis with a few layers of stratum corneum indicated a normal fetus and a healthy infant was born at term. Skin biopsy samples from fetus 2 gave conflicting results; the epidermis of one sample appeared normal but the second had 5-15 layers of incompletely keratinized cells superficial to basal and intermediate layers. The hair canals of both samples were hyperkeratotic. Pelleted amniotic fluid cells contained aggregates of incompletely keratinized epidermal cells and concentric rings of keratinized cells. The fetus was thought to be affected and the pregnancy terminated. Regional variation in epidermal thickness and keratinization was noted upon gross examination of the fetus and by histology of the skin. Marked hyperkeratinization of follicles was evident in all regions. No abnormal keratins were expressed in the affected epidermis but epidermal lipids analyzed from two body regions had a lower triglyceride content and a higher content of free sterols compared with age-matched, normal fetal epidermis. Immunolabeling for markers of differentiation revealed variable stages of epidermal differentiation according to region. Four structurally identical biopsy samples were obtained from a third fetus. The epidermis appeared normal for age and hair canals were keratinized to various extents. The pregnancy was continued and at 33 wk a male infant was born with a severe ichthyosis of the face and scalp and fine, white scaling on the body. The epidermis of both the severely and mildly affected regions of the newborn had a thick, compact stratum corneum and other features of CIE. Scars from all four fetal biopsies were identified on the trunk, in areas which appeared less affected clinically. This study reports, for the first time, the criteria for prenatal diagnosis of CIE and the variable expression of this disorder in the midtrimester fetus. More importantly, it demonstrates the risks and pitfalls of this in utero diagnosis based on epidermal morphology.

Age-related changes in the proportion of types I and III collagen

Previous studies of the age-related changes in interstitial collagens, have suggested that the proportion of type III collagen compared with type I decreases with age. In this study collagen concentration and the proportion of types were measured in heart, lung and skin of male Lewis rats aged between 1 day and 2 years. Collagen concentration, based on hydroxyproline levels, increased in all tissues up until 6 months of age, thereafter it increased in heart and lung, yet decreased in skin. The relative proportions of types I and III collagen were assessed after cyanogen bromide digestion of the tissue and separation of the resultant peptides by sodium dodecyl sulphate polyacrylamide gel electrophoresis. At 2 weeks of age collagen type III represented about one-third of types I and III in all tissues. After this age the proportion of type III increased up to 1 year in both heart (53.9 +/- 1.8%) and lung (47.7 +/- 2.8%), whereas it decreased in skin (18.6 +/- 1.5%). These data show that there are age-related changes in both collagen concentration and the relative proportions of types I and III collagen, but that the direction of these changes differs between tissues.

The function of multiple extracellular matrix receptors in mediating cell adhesion to extracellular matrix: preparation of monoclonal antibodies to the fibronectin receptor that specifically inhibit cell adhesion to fibronectin and react with platelet glycoproteins Ic-IIa

We have identified monoclonal antibodies that inhibit human cell adhesion to collagen (P1H5), fibronectin (P1F8 or P1D6), and collagen and fibronectin (P1B5) that react with a family of structurally similar glycoproteins referred to as extracellular matrix receptors (ECMRs) II, VI, and I, respectively. Each member of this family contains a unique alpha subunit, recognized by the antibodies, and a common beta subunit, each of approximately 140 kD. We show here that ECMR VI is identical to the fibronectin receptor (FNR), very late antigen (VLA) 5, and platelet glycoproteins Ic-IIa and shall be referred to as FNR. Monoclonal antibodies to FNR inhibit lymphocyte, fibroblast, and platelet adhesion to fibronectin-coated surfaces. ECMRs I, II, and FNR were differentially expressed in platelets, resting or activated lymphocytes, and myeloid, epithelial, endothelial, and fibroblast cell populations, suggesting a functional role for the receptors in vascular emigration and selective tissue localization. Tissue staining of human fetal skin localized ECMRs I and II to the basal epidermis primarily, while monoclonal antibodies to the FNR stained both the dermis and epidermis. Experiments carried out to investigate the functional roles of these receptors in mediating cell adhesion to complex extracellular matrix (ECM) produced by cells in culture revealed that complete inhibition of cell adhesion to ECM required antibodies to both the FNR and ECMR II, the collagen adhesion receptor. These results show that multiple ECMRs function in combination to mediate cell adhesion to complex EMC templates and predicts that variation in ECM composition and ECMR expression may direct cell localization to specific tissue domains.

The quantitative investigation of infrared laser effects on the levels of copper and zinc in various tissues

In order to study the effects of infrared laser irradiation on biological systems, the levels of copper and zinc in various irradiated tissues have been investigated. The zinc level in the muscle of the irradiated group increased (P less than 0.001) compared with the control group while in submandibular glands its level decreased (P less than 0.001). The copper levels in these two types of tissues decreased significantly (P less than 0.001). In irradiated skin, both copper and zinc levels increased compared with the control group (P less than 0.005). Quantitative determination of the trace elements copper and zinc indicated the necessity for more detailed studies of the effect of infrared laser irradiation at the cellular level.

The effect of solvent extraction on the lipids of the stratum corneum in relation to observed immediate whitening of the skin

Irritant contact dermatitis along with an increased transepidermal water loss can result from exposing the skin to solvents. A study of the interaction of various solvents with human stratum corneum was made using thin-layer chromatography. Comparison of 10 solvents (trichloroethylene, toluene, dimethylsulfoxide, n-hexane, 1,2-propanediol, carbon tetrachloride, methyl ethyl ketone, ethanol, acetone, distilled water) showed that 3 solvents (dimethylsulfoxide, 1,2 propanediol, distilled water) did not extract lipids from intact human stratum corneum. The findings are discussed in relation to the visual appearance of skin (whitening) after exposure to solvents.

Skin surface sampling for nicotine: a rapid, noninvasive method for identifying smokers

We evaluated a novel, rapid, noninvasive method of skin surface air sampling that detects the presence of nicotine and therefore can identify smokers. The principle of the methodology involved is skin surface air sampling and ion-mobility spectrometry. We studied 93 volunteers and patients; 50 of these gave a positive history for smoking. Skin surface sampling identified 49 of these 50 individuals. Fifty of the 93 individuals provided urine samples. Nicotine was detected in 22 of these urine samples by thin-layer chromatography. Skin surface sampling identified all of these patients. The combination of skin surface air sampling and ion-mobility spectrometry is a rapid, noninvasive screening method for separating smokers from nonsmokers.

Hemorrhagic bullous amyloidosis. A histologic, immunocytochemical, and ultrastructural study of two patients

In patients with bullous hemorrhagic amyloidosis of the skin, the skin lesions were the first manifestations of a plasma cell dyscrasia. Both cases were characterized by similar clinical, histologic, and ultrastructural findings showing an intradermal blister within deposits of amyloid substances. Immunohistologic investigations with a panel of antibodies directed against amyloid fibril proteins showed reactivity of the amyloid deposits with an anti-A lambda serum in both patients.

Immunocytochemical analysis of calcitonin gene-related peptide and vasoactive intestinal polypeptide in Merkel cells and cutaneous free nerve endings of cats

Calcitonin gene-related peptide (CGRP)- and vasoactive intestinal polypeptide (VIP)-immunoreactivity were observed to coexist in Merkel cells of cats. No differences in peptide content were found between Merkel cells located in epithelia of the hard palate, in hairy and glabrous skin of the upper lip, and in vibrissae follicles. CGRP- and VIP-immunoreactive nerve fibres were also found near CGRP/VIP-immunoreactive Merkel cells. In the vibrissae follicles some CGRP- and VIP-immunoreactive nerve terminals end abutting on the glassy membrane. Other CGRP-immunoreactive nerve fibres penetrate the epithelium of the skin and end within it. Electron microscopy of vibrissae follicles revealed that Merkel cell neurites are not immunostained and that immunostained nerve fibres form unmyelinated bundles before ending freely. Thus, CGRP- and VIP-immunoreactive nerve fibres in cat skin do not end as Merkel cell neurites but as different kinds of free nerve endings.

Calorimetric and electron spin resonance examination of lipid phase transitions in human stratum corneum: molecular basis for normal cohesion and abnormal desquamation in recessive X-linked ichthyosis

Lipids appear to play a critical role as regulators of stratum corneum desquamation. In this study, we observed discrete lipid phase transitions at physiologic temperatures in both normal human scale (NHS) and in lipid extracts of NHS by differential scanning calorimetry. In contrast, such thermal transitions were not observed in recessive x-linked ichthyosis scale (RXLIS). To gain further insight into the molecular basis of the lipid phase transitions in NHS vs. RXLIS, comparable samples were evaluated by electron spin resonance, utilizing the perdeuterated probe, di-t-butyl nitroxide. Upon electron spin resonance analysis, both NHS and RXLIS demonstrated thermal phase transitions in the physiologic range; however, the nature of the lipid environments in each type varied. Whereas the environment of the spin probe was more polar in NHS than in RXLIS, the spin probe partitioned into a more "fluid" environment in RXLIS; i.e., the spin probe was more mobile in RXLIS than in NHS lipid matrices. Because an alteration in the cholesteryl sulfate:cholesterol ratio is the primary lipid abnormality in RXLIS, model cholesterol-fatty acid-cholesteryl sulfate mixtures were prepared in proportion to the lipid composition of NHS and RXLIS. Differences were observed in both thermal transitions and in lipid microenvironments in these mixtures that paralleled those observed in scale samples. Based on these results, a model is proposed that invokes abnormal hydrogen bonding, due to increased cholesteryl sulfate, as the mechanism for the abnormal desquamation in recessive X-linked ichthyosis.

[Heterogeneity of collagen molecules types I and II according to their resistance to proteolysis]

Study of the effects of pepsin treatment on soluble collagens type I of the skin and collagens type II of the costal cartilage of healthy subjects revealed the presence of two classes of molecules differing in the stability of their three-helical structure. In collagen molecules possessing a low stability (their number may amount to 20-30%) within the temperature range of 4-30 degrees C pepsin causes a split-off of N-terminal sites with the formation of short chains, i.e., alpha 1(I), alpha 2(II), and alpha 1(II), whereas at higher temperatures (33 degrees C for collagens type I and 37 degrees C for collagens type II) a complete degradation of these molecules takes place. It was found that collagens types I and II molecules contain a high number of three-helical sites with a high susceptibility to pepsin. The putative functional role of structural heterogeneity of collagen molecules is discussed.

Reconstitution of structure and cell function in human skin grafts derived from cryopreserved allogeneic dermis and autologous cultured keratinocytes

Grafts of allogeneic dermis plus autologous epidermal cell cultures were used to replace extensively burned skin. Cryopreserved split-thickness cadaveric skin was grafted onto debrided burn wound, and autologous keratinocytes were cultured from uninjured donor sites. Several weeks later, allograft epidermis was abraded and replaced with the keratinocyte cultures. The final grafts were thus composites of autologous cultured epidermis and allogeneic dermis. In a case with 28 months follow-up, reconstitution of the dermal-epidermal (BMZ.1) and microvascular (BMZ.2) basement membrane zones was studied immunohistochemically and ultrastructurally. Immediately before grafting, thawed cryopreserved skin reacted with antibodies against laminin and type IV collagen in normal patterns. Twenty-nine days after grafting, BMZ.1 reacted weakly with both antibodies, and anticollagen type IV reactivity was absent from BMZ.2. Antilaminin reactivity of BMZ.2, however, was moderately intense, consistent with recent neovascularization. On day 29, the allograft epidermis was replaced with autologous keratinocyte cultures. Twenty-five days later (54 d after allografting), staining of both BMZs was intense with both antibodies. Ultrastructurally, at day 76 (47 d after culture placement) BMZ.1 revealed only small hemidesmosomes, few incipient anchoring fibrils, and a discontinuous lamina densa. BMZ.2, however, was fully reconstituted. By 124 d, both BMZs appeared normal. Observations in the dermis at 76 d included the presence of lymphocytes, organellar debris, and hyperactive collagen fibrillogenesis, all indicative of dermal remodelling. The microvasculature was well differentiated, but no elastic fibers or nerves were found. In the epidermis, melanocytes and evidence of melanosome transfer were seen at 5, 47, and 95 d after grafting of keratinocyte cultures. We conclude that the composite procedure reconstitutes skin with excellent textural and histologic qualities.

Decay-accelerating factor in human skin is associated with elastic fibers

Recently a complement inhibitor, decay-accelerating factor (DAF), has been found in association with uncharacterized fibers in the extracellular matrix of human dermis. Here we show by immunohistochemistry and immunoelectronmicroscopy that DAF is on the periphery of elastic fibers, and that it appears to be associated with some microfibrillar elements that cover the fibers. That DAF is a component of these microfibrils is also suggested by studies of lesional skin from anetoderma, a disease characterized by destruction of elastic fibers. In two patients we found a network of residual fine fibers in the dermis that stain with antibodies against DAF and fibrillin (one of the proteins known to be present in the microfibrils of elastin), but do not stain with antibodies to elastin. Western blot analysis of dermal extracts with monoclonal antibodies to DAF identified a 67 kDa molecule, slightly smaller than membrane DAF, and similar in size to soluble DAF found in secretions. It is possible that together with vitronectin, an inhibitor of the membrane attack complex recently identified in association with elastin, DAF prevents damage of elastic fibers by complement.

Cutaneous IgA subclasses in dermatitis herpetiformis and linear IgA disease

The subclasses of the cutaneous IgA were studied in 8 patients with dermatitis herpetiformis and 4 with linear IgA disease. The cutaneous IgA in dermatitis herpetiformis consisted of both IgA1 and IgA2, although IgA1 predominated. This demonstrated that the IgA is polyclonal and may be both mucosal and blood derived. The IgA in linear IgA disease was exclusively IgA1, confirming previous work, and suggesting that mucosal IgA may not make a major contribution to the skin deposits.

Absence of IL-1 inhibitor in psoriatic scale extracts

In the previous report we found that IL-1-like activity in horny tissue extracts from patients with psoriasis vulgaris and related sterile pustular dermatoses was remarkably low as compared to that in orthokeratotic horny tissue extracts prepared from non-inflammatory skin. In this report we studied the inhibitory activity of lesional horny tissue extracts from three psoriatics on recombinant IL-1-induced thymocyte proliferation in order to search for a possible coexistence of substances which may inhibit thymocyte proliferation. However, we failed to demonstrate any remarkable IL-1 inhibitory activity in each fraction after gel filtration high-performance liquid chromatography of the psoriatic scale extracts or in that of extracts from the plantar callus. We conclude that IL-1 stores are decreased in the pathologic horny layers of psoriatic lesions.

Analysis of collagen content in the fetal wound

The absence of apparent scar formation following the creation of surgical wounds in utero appears to be a phenomenon peculiarly privileged as a sequela of fetal wound healing. Little information exists to explain this disparity from our knowledge of adult wound healing. Therefore, following creation of surgical wounds in fetal rats, at different intervals the healing wounds were harvested and analyzed for collagen content and types. The average proportion of type III collagen was elevated in normal (26.5%) as well as wounded fetal skin (33.8%) when compared with normal levels for the adult (15%). The total collagen content was markedly diminished in the fetal wound. Although embryonal collagen synthesis apparently does exist in fetal reparative processes, the relationship to the lack of gross scarring remains undetermined.

Presence of the Dr receptor in normal human tissues and its possible role in the pathogenesis of ascending urinary tract infection

The Dr hemagglutinin of uropathogenic Escherichia coli recognizes the Dra blood group antigen, a component of the IFC or Cromer-related blood group complex. The present report used the Dr hemagglutinin to demonstrate location of the Dr receptor in selected human tissues and to evaluate the possible use of this lectin as a tissue marker recognizing sites sensitive for bacterial colonization. It was found that the Dr receptor was expressed in different parts of the digestive, urinary, genital, and respiratory tracts, and skin. Intense staining by Dr hemagglutinin was shown in colonic, bronchial, and endometrial glands, and skin eccrine sweat glands. Structures of the urinary tract showing strong fluorescence were renal tubular basement membrane, Bowmans' capsule, and transitional epithelium. The role of Dra antigen as receptor for adhesion for Dr-positive E. coli in ascending colonization of urinary tract and the possible importance of Dra in human pathology is discussed.

[Color and morphological characteristics of the skin in people of different racial groups]

A complex colorimetric, spectrometric and morphological research of race-dependent differences in skin colour and structure has been carried out. Certain regularities in the quantity, distribution and morphological composition of melanin-containing structures and Hb pigment have been revealed in the Russians, Vietnamese, Angolans and Mulattoes. The study has shown that sex differences in skin color depend on hemoglobin concentration--in people of the Caucasian race; both on melanin and hemoglobin concentration--in people of the Mongolian race and only on melanin concentration--in people of the Negroid race.

Mouse hair keratin cDNA: implications and sequences

An efficient method is described for the isolation of mouse hair follicle mRNAs. The RNA contains two peaks of mRNA activity, 11S and 18S. The larger-sized group of mRNAs encodes keratins of 46K, 47K, 58K, 59K, and 63K Mr. cDNAs were prepared using the follicular mRNAs as templates and cloned to produce a library. Initial screening of this library has identified five acidic and six basic mouse hair keratin clones.

Microprobe analysis of chlorpromazine pigmentation

We describe the histochemical, ultrastructural, and microanalytical features of a skin biopsy specimen obtained from a patient with chlorpromazine pigmentation. Golden-brown pigment granules were present in the dermis, predominantly in a perivascular arrangement. The granules stained positively with the Fontana-Masson stain for silver-reducing substances and negatively with Perl's stain for iron. Electron microscopy revealed dense inclusion bodies in dermal histiocytes, pericytes, endothelial cells, and Schwann cells, as well as lying free in the extracellular matrix. These "chlorpromazine bodies" were quite dense even in unosmicated, unstained ultrathin sections, indicating that the pigmentation is related, at least in part, to the inclusions. Microprobe analysis of the chlorpromazine bodies revealed a striking peak for sulfur, which strongly suggests the presence of the drug or its metabolite within these inclusions.

Transiently increased insulin-like growth factor. I. Immunoreactivity in UVB-irradiated mouse skin

UVB-irradiation during 3 d for 90, 180, and 180 sec, respectively, at a daily dose of 0.1 and 0.2 joule/cm2, respectively, induced slight inflammatory reactions in the mouse ear. The insulin-like growth factor I (IGF-I) immunoreactivity, normally demonstrable only in scattered basal epidermal cells, rapidly increased in intensity and frequency in the epidermis. After 3 d of UVB irradiation almost all epidermal cells were outlined by IGF-I immunoreactivity in their plasma membrane. The Langerhans cells expressed intense IGF-I immunoreactivity throughout their cytoplasm. The elevated IGF-I immunoreactivity ceased after 5-7 d and was normalized in 3 weeks. The number of Ia positive epithelial Langerhans cells did not seem to be affected by UVB irradiation. It is concluded that the increased IGF-I immunoreactivity is likely to reflect formation of the trophic peptide IGF-I, most evidently by Langerhans cells, in early events of the inflammatory, reactive response of the skin to UVB irradiation.

Immunofluorescent localization of cytokeratin intermediate filaments as a means of defining the presence of recurrent basal cell carcinoma

Intermediate filament subunits are reliable markers of cytogenetic origin for both normal and neoplastic cells. Immunohistochemical localization of cytokeratin filaments offers a sensitive and specific means of identifying basal or reserve cells when studying histologic sections of skin biopsy specimens. We have applied this technique on eighteen cases in which unequivocal diagnosis or recurrent basal cell carcinoma could not be rendered by conventional histologic techniques. In three of the cases studied, microscopic islands of basal cell carcinoma could be demonstrated by positive staining with cytokeratin antibodies. In the remaining fifteen cases, the possibility of recurrent basal cell carcinoma could be conclusively eliminated on the basis of negative staining with this antibody. Immunolabeling with tissue specific cytokeratin antibodies by indirect immunofluorescent examination may thus constitute a reliable and relatively simple technique that may serve to establish a definitive diagnosis in equivocal cases of suspected recurrent basal cell carcinoma.

Immunocytochemical detection of 1,25-dihydroxyvitamin D receptors in normal human tissues

We developed an immunocytochemical technique to visualize the receptors for 1,25-dihydroxyvitamin D [1,25-(OH)2D receptor] in cryostat sections of normal human tissues, using a rat monoclonal antibody (9A7 gamma) to the chick intestinal receptor, which has been found to react with mammalian 1,25-(OH)2D receptors. Localization of the antigen was predominantly nuclear, with little cytoplasmic immunoreactivity. Specific staining was seen in the nuclei of many normal epithelial tissues, including liver, kidney, thyroid, adrenal, gastrointestinal tract, breast, and skin. No nuclear staining was seen when tissue sections were incubated with normal rat immunoglobulin G or when the monoclonal antibody was preincubated with a receptor-enriched chick intestinal cytosol preparation. Our results demonstrate that the receptor for 1,25-(OH)2D is localized in the nucleus and widely distributed in normal human tissues.

Interferon gamma is a marker for histiocytosis X cells in the skin

In histiocytosis X (HX), which is regarded as a proliferative disease of Langerhans cells (LCs), the tumor cells share characteristic membrane antigens and ultrastructural features with normal LCs. To the present no markers have been described which distinguish HX cells from normal epidermal LCs. Here we report on the selective reactivity of HX cells with a monoclonal antibody against interferon gamma (IFNg). Our results show that HX cells share an epitope with human IFNg while normal LCs do not. It remains to be established whether the expression of IFNg is specific for HX cells or rather characterizes a certain activation state of LCs.

Skin lipid content during early fetal development

Although little is known about changes in the lipid composition of the skin during fetal development, information regarding the developmental sequence of fetal skin lipid content could be important for understanding the emergence of epidermal barrier function, as well as providing baseline criteria for prenatal diagnosis of certain inherited disorders of cornification. In these studies, epidermis was separated from dermis in fetal skin samples ranging from 50 to 140 d, estimated gestational ages (EGA), and its lipid composition was analyzed by quartz rod microchromatography/flame-ionization and thin layer chromatography. Lipid biochemical data were correlated with developmental milestones observed by electron microscopy (morphologic studies). The lipid composition of epidermal and dermal fractions from skin samples between 50 and 110 d EGA was similar, with both tissues exhibiting a predominance of free sterols and phospholipids. After 110 d EGA dermis became enriched in triglycerides, corresponding to the progressive development of adipocytes after this time. EGA epidermis after 110 d was enriched not only in triglycerides, but also sterol esters. Moreover, ceramides and glycosphingolipids also became increasingly prominent, changes that were greatest in epidermis from older fetuses and from cephalad regions. These changes in epidermal lipid composition corresponded morphologically to the progressive emergence of both folliculocentric epidermal cornification and sebaceous gland development.

Dual-label autoradiographic analysis of human skin fibroblast and myoblast proteins by two-dimensional polyacrylamide gel electrophoresis using immobilised pH gradients in the first dimension

Horizontal two-dimensional polyacrylamide gel electrophoresis with immobilised pH gradients in the first dimension has been applied to the analysis of human skin fibroblast and muscle myoblast total cell proteins. Excellent two-dimensional separations of skin fibroblast proteins were obtained using pH 4-10 immobilised pH gradient gels with a long interelectrode distance (16 cm), but resolution was degraded, particularly of the more acidic proteins, by the use of shorter (10 cm) gels. Improved resolution of acidic and basic proteins was obtained using separate pH 4-7 and pH 7-10 immobilised pH gradient gels respectively in the first dimension. Two-dimensional protein maps of skin fibroblast proteins were visualised both by silver staining and by autoradiography of samples labelled synthetically with [35S]methionine. Horizontal two-dimensional electrophoresis, using pH 4-7 and pH 7-10 immobilised pH gradient gels in the first dimension, was applied to the analysis of protein samples from skin fibroblasts and muscle myoblasts dual-labelled synthetically with [35S]methionine and [75Se]selenomethionine in an attempt to identify sets of proteins specific to each cell type. In addition, two-dimensional maps or protein samples derived from normal individuals and patients with Duchenne muscular dystrophy were compared to search for protein changes associated with the disease state. Although sets of qualitative protein spot differences were observed by visual inspection of the two-dimensional gels, more rigorous qualitative and quantitative analysis of the patterns using a computerised analysis system will be required to obtain the maximum amount of information from these data.

Effect of sodium lauryl sulphate and nickel alone and in combination on the skin of guinea pigs

Guinea pig skin was treated with 50 mg/kg sodium lauryl sulphate (SLS) and nickel (Ni) alone and in combination (50 mg/kg SLS and 50 mg/kg Ni) for 7 and 14 days. Release of acid phosphatase, alkaline phosphatase, aspartate aminotransferase, alanine aminotransferase, beta-glucuronidase, lactic dehydrogenase and malic dehydrogenase was observed, following treatment with SLS and Ni alone or in combination. Similarly, the skin contents of amino nitrogen and sulphydryl groups also increased significantly. These alterations were slightly more marked when the skin was treated simultaneously with the combination of SLS and Ni. The present study suggests that industrial workers or populations exposed simultaneously to SLS and Ni are more prone to dermal irritation or inflammation.

A ventrally localized inhibitor of melanization in Xenopus laevis skin

Melanophores normally differentiate in dorsal but not in ventral skin of Xenopus laevis. We have sought factors which might regulate this differentiation pattern, and we have obtained a putative melanization inhibiting factor (MIF) from ventral but not from dorsal skin. Preliminary studies reveal that MIF is destroyed by heat or trypsin treatment, indicating its protein composition, and has a molecular weight in the range of 300 kDa. The effects of MIF on the differentiation of neural crest derivatives to melanophores were examined in vitro in the presence of tyrosine and fetal calf serum (FCS). Tyrosine enhances melanophore differentiation in vitro at concentrations equivalent to those estimated in adult Xenopus blood plasma (20 microM). FCS also stimulates melanization, by way of materials other than the tyrosine contained in FCS. MIF strongly inhibits outgrowth and melanization of neural crest cells from neural tube explants. MIF also inhibits the differentiation of melanoblasts contained in cultured explants of ventral skin. Inhibition of melanization or melanophore differentiation by MIF occurs even in the presence of L-tyrosine and/or FCS. We suggest that MIF plays an important role in the establishment of dorso-ventral pigment patterns in amphibia.

Application of solid-state nuclear magnetic resonance (NMR) to the study of skin hydration

The solid-state nuclear magnetic resonance (NMR) technique of carbon-13 cross-polarization/magic angle spinning (CP/MAS) has been successfully used to obtain high-resolution spectra of whole-thickness, hairy rat skin and to characterize the influence of hydration on the efficiency of cross-polarization and the proton spin-lattice relaxation time in the rotating frame (T1pH). Spectra obtained with hydrated samples, which were obtained with 50% more accumulations, had comparable signal-to-noise ratio relative to spectra obtained with dried skin, indicating a disordering effect with the presence of water. The integrated area of spectra of low-shifted peaks rose more rapidly with increasing contact time relative to the high-shifted peaks for both hydrated and dried skin. In addition, the carbonyl intensity of the hydrated skin relative to dried skin reached a maximum at shorter times, reflecting an efficient relaxation mechanism of the protons. The shift of the peak maximum to shorter mixing times quantitatively reflects the interaction of the protons of water with the carbonyl moiety.