Automatic algorithm for the characterization of sweat ducts in a three-dimensional fingerprint

In this study, an automatic algorithm has been presented based on a convolutional neural network (CNN) employing U-net. An ellipsoid and an ellipse were applied for approximation of a three-dimensional sweat duct and en face sweat pore at the different depths, respectively. The results demonstrated that the length and the diameter of the ellipsoid can be used to quantitatively describe the sweat ducts, which has a potential for estimating the frequency of resonance in millimeter (mm) wave and terahertz (THz) wave. In addition, projection-based sweat pores were extracted to overcome the effect that the diameters of en face sweat pores depend on the depth. Finally, the projection-based image of sweat pores was superposed with a maximum intensity projection (MIP)-based internal fingerprint to construct a hybrid internal fingerprint, which can be applied for identification recognition and information encryption.

Novel Mutations in CLN5 of Chinese Patients With Neuronal Ceroid Lipofuscinosis

Neuronal ceroid lipofuscinosis is a hereditary disease, and ceroid-lipofuscinosis neuronal protein 5 (CLN5) has been proved to be associated with neuronal ceroid lipofuscinosis. Here we report 3 patients from 2 families diagnosed with CLN5 neuronal ceroid lipofuscinosis. Whole genome sequencing of DNAs from 3 patients and their families revealed 3 novel homozygous mutations, including 1 deletion CLN5.c718 719delAT and 2 missense mutations c.1082T>C and c.623G>A. We reviewed 278 papers about neuronal ceroid lipofuscinosis resulting from CLN5 mutations and compared Chinese cases with 27 European and American cases. The overall age of onset of European and American patients occur mainly at 3 to 6 years (66%, 18/27), 100% (27/27) of patients had psychomotor regression, 99% (26/27) patients presented vision decline, and 70% (19/27) of patients suffered seizures. In China, the age of onset in 3 patients was 5 years, but for 1 patient it was at 17 months. Four Chinese patients presented psychomotor deterioration and seizures; only 1 had visual problems.

Histological study of white rhinoceros integument

In this study, we report findings from a microscopic analysis of the white rhinoceros (Ceratotherium simum) integumentary ultrastructure. Skin samples from the cheek, shoulder, flank and rump were taken from a 46-year-old female southern white rhinoceros and examined using H&E and elastic histological stains. The epidermis was thickest in the flank (1.003 mm) followed by the rump, cheek and shoulder. The stratum corneum comprised more than half the epidermal thickness. Numerous melanin granules were found in the basal and spinosum layers. The epidermal-dermal junction was characterized by abundant papillary folds increasing surface contact between integument layers. Most of the dermal thickness consisted of organized collagen bundles with scattered elastic fibers. Collagen fiber bundles were thickest in the flank (210.9 μm) followed by shoulder, rump and cheek. Simple coiled sweat glands were present in the dermis, but hair and sebaceous glands were absent. Together, these data suggest the white rhinoceros has a unique integumentary system among large terrestrial herbivores.

[Structure of the sweat glands in essential axillar hyperhidrosis and after its surgical treatment]

The structure of sweat glands in their skin portions in axillar regions was investigated in essential hyperhydrosis and after its treatment using mechanical curettage, performed solely or in combination with ultrasonic destruction. There was shown, that hyperhydrosis is accompanied by the sweat glands canaliculus secretory portion enlargement and their diameter as well. Additionally, the secretory epithelium area is practically enhanced twice as in a control and its thickness - in 1.5 times. Curettage is accompanied with removal, along with hypoderma, of majority of the sweat glands terminal portions and, due to evolvement of a dense connective tissue regenerate, prophylaxes their regeneration with a staged hypotrophy of residual secretory portions. The combined application of curettage with ultrasonic destruction, during treatment of hyperhydrosis, secures more prominent, alike while only curettage performance, reduction of terminal parts of sweat glands. It takes place on background of the inflammatory reaction reduction and the connective tissue subtle regenerate formation. Surgical methods of treatment, alike botulotoxin injections, secures more pronounced and persistent reduction of sweat glands in hyperhydrosis.

Chloride transport in NCL-SG3 sweat gland cells: Channels involved

The aim of the study was to assess whether NCL-SG3, the only immortalized sweat gland cell line available, can be used as an in vitro model to study chloride ion transport in cultured sweat gland cells. Cl(-) efflux was measured using the MQAE dye fluorescence technique after stimulating the cells with different agonists. A significant stimulation of chloride efflux was achieved with the calcium ionophore A23187 resulting in an efflux rate of 0.9 mM/s. Both ATP and UTP activated chloride efflux in these cells, with the ATP response being larger. IBMX and forskolin stimulation did not induce a rate of chloride efflux above the basal level. Immunocytochemistry showed no detectable CFTR in NCL-SG3 cells. This finding was confirmed with flow cytometry analysis. Niflumic acid (20 and 100 microM NFA) and 4,4'-diisothiocyanatodihydrostilbene-2,2'-disulfonic acid (H2DIDS) (100 ìM) decreased the rate of ATP-stimulated chloride efflux significantly (0.40 and 0.31 mM/s with NFA, 0.37 mM/s with H2DIDS). Gadolinium (20 ìM) had no effect on the chloride transport rate. In conclusion, the NCL-SG3 cells retain some of the aspects of human sweat gland epithelium, such as the ability to form cell-cell contacts. The CFTR protein is neither functional nor expressed in cultured NCL-SG3 sweat gland cells. Ca(2+)-activated chloride conductance is confirmed and the putative Ca(2+)-activated chloride channel (CaCC) is further characterized in term of its pharmacological sensitivity. The NCL-SG3 sweat gland cell line can be used to investigate the characteristics of the CaCC and to identify the channel.

Two novel CLN5 mutations in a Portuguese patient with vLINCL: insights into molecular mechanisms of CLN5 deficiency

The neuronal ceroid-lipofuscinoses are the most common neurodegenerative disorders in childhood characterized by progressive blindness, epilepsy, brain atrophy, and premature death. Based on the age at onset, disease progression and ultrastructural features three classical (infantile, late-infantile, and juvenile) and three variant late-infantile forms are generally distinguished (Finnish variant, Costa Rican variant, and epilepsy with progressive motor retardation). The Finnish variant late-infantile form has been associated with CLN5 gene defects, with only five mutations described to date. We report a patient with vLINCL/CLN5 who represents the first evidence of the disease in the Portuguese population. Mutational screening revealed the previously described missense mutation c.835G>A (D279N) inherited from the mother, and two novel mutations, c.565C>T (Q189X) and c.335G>C (R112P) from paternal and maternal inheritance, respectively. Based on data here reported: (i) the number of possible mutations in CLN5 gene is now 7; (ii) the CLN5 Portuguese case represents the third description of the disease outside northern Europe; (iii) the CLN5/mRNA expression level reduced to 45% supports the existence of one mRNA non-producing allele, further noticeable at the protein level; (iv) Western blotting data using a specific antibody to human CLN5p provided evidence for the presence of four integral membrane isoforms in human fibroblasts; (v) data from differential expression of CLN2, CLN3, and CLN5 suggest down-regulation of CLN3 gene expression in CLN2 and CLN5-deficient human patients and this observation strengths the hypothesis of functional redundancy of the CLN system.

NKCC1 and NHE1 are abundantly expressed in the basolateral plasma membrane of secretory coil cells in rat, mouse, and human sweat glands

In isolated sweat glands, bumetanide inhibits sweat secretion. The mRNA encoding bumetanide-sensitive Na+-K+-Cl− cotransporter (NKCC) isoform 1 (NKCC1) has been detected in sweat glands; however, the cellular and subcellular protein localization is unknown. Na+/H+ exchanger (NHE) isoform 1 (NHE1) protein has been localized to both the duct and secretory coil of human sweat duct; however, the NHE1 abundance in the duct was not compared with that in the secretory coil. The aim of this study was to test whether mRNA encoding NKCC1, NKCC2, and Na+-coupled acid-base transporters and the corresponding proteins are expressed in rodent sweat glands and, if expressed, to determine the cellular and subcellular localization in rat, mouse, and human eccrine sweat glands. NKCC1 mRNA was demonstrated in rat palmar tissue, including sweat glands, using RT-PCR, whereas NKCC2 mRNA was absent. Also, NHE1 mRNA was demonstrated in rat palmar tissue, whereas NHE2, NHE3, NHE4, electrogenic Na+-HCO3− cotransporter 1 NBCe1, NBCe2, electroneutral Na+-HCO3− cotransporter NBCn1, and Na+-dependent Cl−/HCO3− exchanger NCBE mRNA were not detected. The expression of NKCC1 and NHE1 proteins was confirmed in rat palmar skin by immunoblotting, whereas NKCC2, NHE2, and NHE3 proteins were not detected. Immunohistochemistry was performed using sections from rat, mouse, and human palmar tissue. Immunoperoxidase labeling revealed abundant expression of NKCC1 and NHE1 in the basolateral domain of secretory coils of rat, mouse, and human sweat glands and low expression was found in the coiled part of the ducts. In contrast, NKCC1 and NHE1 labeling was absent from rat, mouse, and human epidermis. Immunoelectron microscopy demonstrated abundant NKCC1 and NHE1 labeling of the basolateral plasma membrane of mouse sweat glands, with no labeling of the apical plasma membranes or intracellular structures. The basolateral NKCC1 of the secretory coils of sweat glands would most likely account for the observed bumetanide-sensitive NaCl secretion in the secretory coils, and the basolateral NHE1 is likely to be involved in Na+-coupled acid-base transport.

Aberrant gating, but a normal expression pattern, underlies the recessive phenotype of the deafness mutant Connexin26M34T

Mutations in the gene GJB2, encoding the gap junction protein Connexin26 (Cx26), are the most prevalent cause of inherited hearing loss, and Cx26M34T was one of the first mutations linked to deafness (Kelsell et al., 1997; Nature 387, 80-83). We report the first characterization of the gating properties of M34T, which had previously been reported to be nonfunctional. Although homotypic mutant channels did not produce detectable currents, heterotypic pairings with wtCx26 confirmed that M34T formed intercellular channels, although the gating properties were altered. Cx26M34T displayed an inverted response to transjunctional voltage (Vj), mediating currents that activate in a time- and Vj-dependent manner. These characteristics suggest that the channel population is only partially open at rest, consistent with previous reports that dye transfer in M34T-expressing cells is reduced or abolished (e.g., Thonnissen et al., Human Genet. 111, 190-197). To investigate the controversial recessive/dominant behavior of this mutant, we coexpressed M34T with wtCx26 RNA at equimolar levels, mimicking the situation in heterozygotic individuals. Under these conditions, M34T did not significantly reduce Cx26/Cx26 coupling, or alter the electrophysiological properties of the wt channels, consistent with the recessive nature of the allele. Overexpression of the mutant did have some inhibitory effects on conductance, possibly explaining some of the previous reports in exogenous expression systems and some patients. Consistent with its electrophysiological behavior, we also show that M34T localizes to cell junctions in both transfected HeLa cells and patient-derived tissue.

Immunohistochemical localization of glial cell line-derived neurotrophic factor and its receptor Ret in the rat sweat gland

Glial cell line-derived neurotrophic factor (GDNF) was initially identified as a neurotrophic factor for dopaminergic neurons but its effects are not restricted to nervous tissue. It is reported that GDNF-induced intercellular signaling is necessary for the normal development of a variety of non-neural tissues. In this study, immunoreactivities of both GDNF and its functional receptor Ret were evaluated in normal adult rat sweat gland by light and electron microscopy. Ret was found in the epithelial cells of the excretory duct and the coiled secretory terminal of the sweat gland. Electron microscopic observation of the secretory epithelium showed that Ret immunoreactivity is localized in the basal area of the secretory cells, facing myoepithelial cells, but it was not observed in the basal infolding or in the apical region of these cells. On the other hand, GDNF was observed in most myoepithelial cells of the coiled secretory portion of the sweat gland and in a small number of nerve fibers innervating the gland. Although the GDNF-containing nerve fibers cannot be negated as a source of the ligand for Ret in the secretory cells, the finding that GDNF and Ret are localized face to face in adjoining cells in the sweat gland implies another novel trophic role of GDNF in this tissue.

Clinicopathological and molecular characterization of neuronal ceroid lipofuscinosis in the Portuguese population

A series of 53 Portuguese patients (derived from 43 families) born in the period 1963-1999 have been diagnosed with neuronal ceroid lipofuscinosis (NCL) based on clinicopathological findings. Plotting the cumulative number of new cases per year against the year of birth resulted in a slightly S-shaped curve, with a nearly straight central segment over a period of 14 years (1977-1990) indicating a continuous registration of new cases born during the corresponding time period. In this period the prevalence of overall NCL in the Portuguese population was calculated to be 1.55 per 100.000 live births.Twenty-six patients from 20 unrelated families were further evaluated by combining clinicopathological with biochemical and genetic data. No intra-familial heterogeneity was observed. Four sub-types of childhood NCL were identified: infantile NCL (INCL) with granular osmiophilic inclusions (GROD) and PPT1 deficiency (1/26), classical LINCL with curvilinear (CV) inclusions and tripeptidyl peptidase (TPP1) deficiency (3/26), variant late infantile NCL (LINCL) with fingerprint/curvilinear (FP/CV) inclusions and normal TPP1 enzyme activity (11/26) and juvenile NCL (JNCL) with a mix of FP/CV (11/26). Eight of 11 JNCL patients were homozygous for the 1.02-kb deletion in the CLN3 gene, and 3 were heterozygous with an unidentified mutation in the second allele. The 1.02-kb deletion in the CLN3 gene accounted for 86.3 % (19/22) of CLN3-causing alleles and 36.5 % (19/52) of childhood NCL defects. The causal mutations for CLN1 and CLN2 were V181M (2/2) and R208X (4/6), respectively. CLN1, CLN2 and CLN3 affected 3.8 %, 11.5 % and 42.3 % of NCL Portuguese patients, respectively. In 42.3 % of patients affected by the vLINCL form, CLN3, CLN5 and CLN8 gene defects were excluded by direct sequencing of cDNA. Genetic variants such as CLN6 might therefore cause a significant portion of childhood NCL in the Portuguese population. The relative frequency of classical childhood forms of NCL in the Portuguese population is reported and contributes to the knowledge of genetic epidemiology of these world-widely distributed disorders.

PACAP activated adenylate cyclase in human sweat glands. An ultracytochemical study

The ultracytochemical localization of adenylate cyclase (AC) was studied after stimulation with pituitary adenylate cyclase activating peptide (PACAP) in human sweat glands. PACAP stimulated AC in both eccrine and apocrine glands. In the secretory cells, enzymatic activity was associated with membranes involved in the secretory mechanism. In both glands, the cells of the excretory duct and myoepithelial cells presented AC activity. These localizations of enzymatic activity suggest a role for PACAP in regulating glandular secretion.

Confocal endoscopy via structured illumination

We describe a simple modification to a rigid endoscope so as to provide both high-quality conventional and confocal images of reasonably accessible regions of the body. This versatile system uses a structured illumination approach together with a conventional incoherent illumination source. Images taken in fluorescence are presented using this combined conventional and confocal endoscope.

Localization of aquaporin-5 in sweat glands and functional analysis using knockout mice

Sweat secretion involves the transport of salt and water into the lumen of the secretory coil of the sweat gland. By analogy to salivary and submucosal glands, where fluid secretion is aquaporin-5 (AQP5) dependent, we postulated that aquaporin water channels might facilitate sweat secretion. Immunolocalization with specific antibodies revealed strong expression of AQP5 at the luminal membrane of secretory epithelial cells in sweat glands in mouse paw skin. Novel quantitative methods were developed to compare sweat secretion in wild-type mice and mice lacking AQP5. Total hindpaw sweat secretion was measured by proton nuclear magnetic resonance of sweat-derived (1)H(2)O in (2)H(2)O solvent, and sweat secretion from individual glands was measured by real-time video imaging of sweat droplet formation under oil. Sweat secretion rates after pilocarpine stimulation did not differ in wild-type mice (0.21 +/- 0.03 nl min(-1) gland(-1)) vs. mice lacking AQP5 (0.19 +/- 0.04 nl min(-1) gland(-1)). The lack of effect of AQP5 on sweat secretion rate was confirmed by microcapillary collections of sweat from defined regions of mouse paws. Also, as by direct counting of droplets, the number of functional sweat glands was not affected by AQP5 deletion. Sweat gland morphology was similar in wild-type and AQP5 null mice. From sweat coil geometry and gland secretion rate, the rate of fluid secretion was estimated to be 130 nl min(-1) cm(-2) of secretory epithelium, substantially lower than that of > 500 nl min(-1) cm(-2) in kidney proximal tubules and salivary glands, where active fluid absorption or secretion is aquaporin dependent. These results indicate the expression of AQP5 in sweat gland secretory epithelium, but provide direct evidence against its physiological involvement in sweat fluid secretion in mice.

Langerhans cells within the follicular epithelium and the intradermal sweat duct in equine insect hypersensitivity "Kasen"

Histopathologic and electron microscopic observations were given on Langerhans cells (LCs) within the follicular epithelium (FE) and intradermal sweat duct (ISD) of equine "Kasen". By light microscopy, LCs were present in the greatest numbers within the FE and ISD than within the epidermal layer and the normal skin, with an occasional formation of several aggregated foci. By electron microscopy, LCs within the FE and ISD widely extended their dendritic processes between the keratinocytes and contained Birbeck granules (Bgs), mitochondria, rough endoplasmic reticula and ribosomes in the cytoplasm. Numerous Type 2 LCs, with a number of Bgs and endocytosis, and Type 3 LCs, with multivesicular bodies and endosomes of various sizes, were recognized within the FE and ISD, although inactive Type 1 LCs, with a narrow and lucid cytoplasm, were rarely seen. LCs observed within the FE and ISD in the "Kasen" skin lesions might express the particular stage corresponded to recognize, intake and process the antigens which permeate them.

Diagnostic value of electron microscopy in a case of juvenile neuronal ceroid lipofuscinosis

Neuronal ceroid lipofuscinoses (NCLs) represent a large group of inherited neurodegenerative disorders characterized by an abnormal accumulation of lipopigment in neuronal and extraneuronal cells. The authors present a case of juvenile neuronal ceroid lipofuscinosis in a 7-year-old boy. Ultrastructural examination of a skin biopsy disclosed deposits of curvilinear profiles and fingerprint-like structures in epithelial cells of sweat glands, endothelial cells, peripheral nerve endings, and fibroblasts. These findings allowed specific confirmation of the assumed diagnosis of juvenile neuronal ceroid lipofuscinosis. Due to the genotypic and phenotypic variability within the group of NCLs, the clinical investigation may be long and complicated. With the NCL disorders in mind, an accurate diagnosis based on ultrastructural examination of a skin biopsy may shorten this investigation, thus benefitting the patient.

Atrial natriuretic peptide and guanylin-activated guanylate cyclase isoforms in human sweat glands

The ultracytochemical localization of membrane-bound guanylate cyclases A and C, stimulated by atrial natriuretic peptide and guanylin respectively, has been studied in human sweat glands. The results showed that the peptides stimulated guanylate cyclases A and C in both eccrine and apocrine glands. In the secretory cells, enzymatic activity was present on the plasma membranes and on intracellular membranes involved in the secretory mechanism. In eccrine glands, the cells of the excretory duct also presented enzymatic activity on the plasma membranes. In both glands, myoepithelial cells, surrounding the secretory cells, exhibited only guanylate cyclase A activity. These localizations of enzymatic activity suggest a role for both atrial natriuretic peptide and guanylin in regulating glandular secretion.

Sweat gland toxicity induced by bis (tributyltin) oxide: an ultrastructural and X-ray microanalysis study

Acute toxicity of bis (tributyltin) oxide in the sweat glands in the rat footpad was investigated by electron microscopy and an energy-dispersive X-ray microanalyzer. Male Wistar rats received an intramuscular injection of 0.5 ml/kg bis (tributyltin) oxide. After 6-8 h, swelling of mitochondria appeared in the secretory cells of the sweat glands. After 12 h, the secretory cells began to show intracytoplasmic edema. After 16-20 h, secretory cells in some sweat glands showed marked hydropic degeneration with swollen cytoplasm. Using X-ray microanalysis, tin peaks were preferentially obtained from the swollen mitochondria of the affected secretory cells. Mitochondria dysfunction due to the toxic effects of bis (tributyltin) oxide induced changes in the secretory cells of rat sweat glands. After 24-48 h, the secretory portion of the sweat glands contained three types of cells: degenerating dark cells, regenerating cells carrying injured mitochondria, and light cells which were morphologically very similar to the cells in the transitional portion of the sweat gland. These light cells appeared to differentiate into active secretory cells after settling down in the secretory portion. Based on these observations, we concluded that the cells in the transitional portion could play an important role at least as reserve cells against secretory cell toxicity. In association with the regenerating process of the damaged secretory portions, increased mitotic activities were seen in different areas of all the dermal sweat ducts. The above-mentioned morphological observations for cell damage and subsequent regeneration and renewal ofsecretory cells in sweat gland intoxication have not been reported so far.

Cerebriform plantar hyperplasia: ultrastructural study of two cases

In the present work we report the histopathological features of the cerebriform plantar hyperplasia observed in two patients with a mild form of the Proteus syndrome. Light microscopy revealed increased fibro-adipose tissue and adnexal structures in the dermis. Ultrastructurally, densely packed collagen fibrils variable in diameter and configuration, described as composite fibrils and unraveled fibrils, as well as a few fragmented elastic fibrils presenting an altered ratio between the elastin and the microfibrillar components were the major features observed. We consider that these histopathological findings will contribute to further delineate cerebriform plantar hyperplasia and also to establish clues for the early diagnosis of the Proteus syndrome.

Juvenile neuronal ceroid lipofuscinosis

A case of juvenile neuronal ceroid lipofuscinosis (JNCL) diagnosed on the basis of clinical features, electrophysiologic studies and skin electron microscopy is reported. JNCL was suspected on the basis of characteristic symptoms including progressive loss of vision, seizures, mental retardation and motor disabilities. Diagnosis was confirmed by neurophysiological and biopsy studies. The disease is caused by 23 different mutations in a gene recently isolated on chromosome 16 p11.2-12.1. Although universally fatal, characterisation of mutations can help in prenatal diagnosis in future pregnancies.

Immunohistochemical evidence suggests intrinsic regulatory activity of human eccrine sweat glands

Immunohistochemistry of normal eccrine sweat glands was performed on paraffin sections of human skin. Immunoreactivity (ir) for neuron specific enolase, S100 protein (S100), regulatory peptides, nitric oxide synthase type I (NOS-I) and choline-acetyltransferase (ChAT) was found in small nerve bundles close to sweat glands. In the glands, secretory cells were labelled with anticytokeratin antibody. Using antibodies to S100, calcitonin gene-related peptide (CGRP) and substance P (SP) a specific distribution pattern was found in secretory cells. Granulated (dark) and parietal (clear) cells were immunopositive for CGRP, and S100 and SP, respectively. Immunoreactivity was diffuse in the cytoplasm for CGRP and S100, and peripheral for SP. Myoepithelial cells were not labelled. Electron microscopy revealed electron dense granules, probably containing peptide, in granulated cells. Using antibodies to NOS-I and ChAT, ir was exclusively found in myoepithelial cells. Immunoreactivity for the atrial natriuretic peptide was absent in sweat glands. These results provide evidence for the presence of both regulatory peptides involved in vasodilation and key enzymes for the synthesis of nitric oxide and acetylcholine in the secretory coil of human sweat glands. It is suggested that human sweat glands are capable of some intrinsic regulation in addition to that carried out by their nerve supply.

Morphological and ultrastructural study of carpal organ in adult female wild swine

The carpal organ of adult female wild swine is a sweat-type gland which secretes an odorous substance. The gland consists of 5-7 lobes, each made up of lobules with convoluted glandular tubules. The gland secretion is transported in large excretory canals which empty from 5 to 7 clearly visible pores. An ultrastructural examination showed that the glandular tubules are made up of single-layered epithelium with different types of cells. One type, with rather electron-dense cytoplasm, is secretory cells full of granular material which empties into the tubule lumen. A second cell type has a glycogen-rich, transparent cytoplasm. Its role appears to be secreting a watery, electrolyte-containing liquid. In the intermediate zone of the tubules, there is a third type of cell with transparent cytoplasm. Its ultrastructural characteristics seem to indicate that its function is to reabsorb the excess watery component. In the wall of the glandular tubules, outside the epithelium, there are myoepithelial cells which facilitate the movement of the secretions toward the collector canal.

Apocrine sweat glands in the circumanal glands of the dog

Apocrine sweat glands in the circumanal glands of the dog are not connected morphologically with the lobules of the circumanal glands. However, an apparent functional association has been demonstrated and it is possible that the apocrine sweat glands might serve as excretory ducts for degenerated polyhedral cells of the circumanal glands. In this study, we examined the ultrastructure of the apocrine sweat glands in the circumanal glands of the dog in an effort to define more precisely the relationship between the apocrine sweat glands and the circumanal glands. Paraffin sections stained with azan and sections after immunohistochemical staining with antibodies against actin were examined by light microscopy. Samples fixed by aldehyde perfusion were examined with the electron microscope. Diameters of apocrine sweat glands and height of cells in the secretory epithelium varied considerably. Immunohistochemical staining for actin was weakly positive in the supranuclear regions of secretory cells and very intense in myoepithelial cells. In secretory cells, the endoplasmic reticulum was well-developed. Multivesicular bodies were abundant and were discharged into lumens. Apocrine secretion and exocytosis were observed at luminal surfaces of secretory cells. There were three types of large granule in the cytoplasm: giant mitochondria without cristae; membrane-enclosed globules with or without myelin-like contents; and electron-dense, homogeneous, globular structures. Luminal surfaces were always covered with microvilli, and extensive folding of the cell membrane was found in basal regions. Bundles of actin filaments were dispersed throughout the cytoplasm. In the lumens of apocrine tubules, we observed shed secretory cells with well-preserved normal fine structures. We also noted the differentiation of secretory cells that was due to cell renewal. Apocrine sweat glands in the circumanal glands of the dog appear to be more active than those on the general body surface in terms of apocrine secretion, exocytosis, and the release of multivesicular bodies. Shed secretory cells containing large granules, as well as degenerated polyhedral cells from the circumanal glands, might contribute, to some extent, to the subtle composition of sweat from these apocrine sweat glands.

Sclerosing sweat-duct carcinoma (malignant syringoma) of the upper eyelid: a patient report with immunohistochemical and ultrastructural analysis

Sclerosing sweat-duct carcinoma or malignant syringoma is a rare eyelid tumor. The authors report the first patient with sclerosing sweat-duct carcinoma involving the upper eyelid and present its immunohistochemical and ultrastructural features. The clinical features and the histopathologic and ultrastructural findings that distinguish this tumor from its benign counterparts are discussed. Sclerosing sweat-duct carcinomas are slow growing but locally invasive neoplasms that have a propensity to recur. Wide and deep surgical excision with frozen section evaluation of margins is recommended.

Regulation of ion content in primary cultures from reabsorptive ducts of human sweat glands studied by X-ray microanalysis

X-ray microanalysis was used to investigate whether cAMP- and/or Ca2+-activated regulation of chloride and potassium efflux is expressed in primary cultures of sweat gland duct cells. The effects of extracellular UTP and ATP on the duct cells, and the signalling system involved in the response to ATP was also studied. Primary cultures from duct cells of human sweat glands responded to 1 microM carbachol, 2 microM of the Ca2+ ionophore A23187, or 5 mM 8-bromo-cAMP stimulation for 5 min, resulting in a decrease in cellular Cl and K concentrations. 50 microM 5-nitro-2-(3-phenylpropyl-amino)-benzoic acid (NPPB), a Cl- channel blocker, can inhibit the decrease in Cl concentration induced by cAMP. Extracellular (200 microM) ATP caused a decrease of Cl and K in cultured duct cells, while (200 microM and 2 mM) UTP was ineffective. Both the phosphoinositidase C inhibitor U73122 (10 microM) and the absence of extracellular Ca2+ abolished the ATP-induced decrease in Cl and K content. Alloxan (1.25 mM), an adenylate cyclase inhibitor, had an inhibitory effect on the response to ATP. The decrease in K, but not in Cl, content in the cells elicited by ATP was blocked by prior incubation with 100 ng/ml pertussis toxin, indicating the coupling of ATP to pertussis toxin-sensitive G-proteins. In conclusion, both Ca2+- and cAMP-dependent Cl- permeability is present in primary cultures from duct cells of human sweat gland. The response to ATP can be mediated both by Ca2+- and by cAMP-dependent pathways, and is coupled to pertussis toxin-sensitive G-proteins.

Acquired idiopathic generalized anhidrosis with isolated sudomotor neuropathy

The pathogenesis and underlying lesion of acquired idiopathic generalized anhidrosis (AIGA) are apparently heterogeneous. We report a patient with AIGA in whom the eccrine glands were histologically normal. However, electron microscopic examination showed markedly low numbers of nerve terminals and unmyelinated axons associated with the eccrine glands. Our laboratory investigations suggest that degeneration of postganglionic sympathetic cholinergic nerve may be the underlying pathogenetic mechanism of anhidrosis in this patient.

Cerium ions in the histochemical demonstration of second-messenger enzymes

Second-messenger systems are involved in the regulation of numerous cellular processes. Adenylate cyclase (AC) and guanylate cyclase (GC) enzymes are in key positions in the regulation of these systems. The cerium method has been successfully applied to demonstrate amine- and neuropeptide-stimulated AC in rat nervous and adipose tissues and human sweat glands at the electron microscopic level. AC was also localized in cultured neurons. Nitric oxide compounds stimulated GC were demonstrated in rat hippocampal areas. Enzyme reactions were located in neurons pre- and postsynaptically in synapses; in addition, GC activity was seen intraneuronally and in glial cells. Adipocytes and eccrine glandular cells exhibited reaction products in their plasmalemmas. Optimal histochemical conditions are described, combined with control experiments. Some handicaps, related to the sensitivity of the enzymes to the fixatives, penetration problems of cerium salts, and especially the specificity of the method in phosphatase enzyme histochemistry in general are discussed.

Sweat gland vacuoles in Unverricht-Lundborg disease

We report a re-evaluation of skin biopsies of 4 patients with Unverricht-Lundborg (UL) disease showing membrane-bound bodies in sweat glands. The previously described findings in 5 patients by Cochius et al. (1994) are confirmed. The data suggest that skin biopsy may be a useful mean for confirmation of diagnosis in this disorder, but the specificity of these findings is to be proved by examination of a larger number of cases.

Ultrastructural localization of carcinoembryonic antigen (CEA) glycoproteins and epithelial membrane antigen (EMA) in normal and neoplastic sweat glands

Glycoproteins of the carcinoembryonic antigen family (CEA) and epithelial membrane antigen (EMA) are established markers for glandular and mucosal tissues. However, their precise ultrastructural distribution in sweat glands has not been determined as yet. Therefore, normal human skin, 19 cases of various sweat gland neoplasms, Paget's disease, and cutaneous metastases of visceral carcinomas were stained with well-defined antibodies using a postembedding immunogold technique. In some cases, a new method of re-embedding paraffin material for immunoelectron microscopy was applied. In normal sweat glands, immunoreactivity of the endoplasmic reticulum and vesicles indicated biosynthesis and processing of CEA and EMA. Along the luminal surfaces both CEA and EMA represented an integral part of microvilli. However, a differential expression of CEA and EMA was demonstrated in apocrine epithelia, mucous cells of eccrine glands, and sweat ducts. In fetal glands, CEA was associated with formation of secretory and ductal lumina. The overall cellular distribution of CEA and EMA was highly preserved in benign sweat gland neoplasms whereas malignant neoplasms were characterized by loss of protein targeting and cellular polarity. In conclusion, these immunoelectron microscopical findings suggest a role of CEA and EMA for cell differentiation and secretory mechanisms of sweat gland epithelia.

Use of primary cell cultures and intact isolated glandular epithelia for X-ray microanalysis

Changes in the elemental composition of cells during isolation of glandular epithelia were studied by electron probe X-ray microanalysis. Fine chopping of rat submandibular gland followed by enzymatic treatment for 15 min caused marked increases in Na and Cl and a decrease in K concentrations in acinar cells. After enzymatic treatment for 50 min, Na, Cl and K concentrations returned to close to the control level. Mechanical disaggregation of the acinar clumps following enzymatic treatment resulted again in minor increases in Na and Cl and a marked decrease in K concentration. Exposure of isolated acini to cholinergic stimulation in vitro resulted in secretion of Cl and K from the acinar cells. Dissection of the sweat gland from human skin caused a decrease in the K/Na ratio. Incubation of the gland for 30-45 min with collagenase gave rise to a gradual decrease in the K/Na ratio. After mechanical separation of the gland into the secretory coil and reabsorptive duct, a further reduction of the K/Na ratio was seen. However, the duct cells had a much lower K/Na ratio and higher Ca concentration than the coil cells. In primary cultures, the K/Na ratios of the coil and duct cells returned to the in situ level. The elemental composition of sweat gland cells incubated in collagenase-containing medium was no different from that in cells incubated in collagenase-free medium. In the intact collagenase-isolated tissue, Cl- secretion in the coil was elicited by carbachol but not by cAMP, whereas in the duct cells the reverse was the case. In primary cell cultures, Cl- efflux in both coil and duct cells could be elicited by both carbachol and cAMP. In conclusion, although changes in elemental composition of gland cells during the isolation procedure occur, physiological responses can be detected. When primary cell cultures are used, it should be borne in mind that cultured cells may have physiological properties different from those of the intact tissue.

Ionic mechanisms of Ca(2+)-dependent electrolyte transport across equine sweat gland epithelium

1. The ionic mechanism involved in Ca(2+)-stimulated electrolyte transport in cultured equine sweat gland epithelial cells was studied using the short-circuit current (ISC) technique. 2. Microscopy revealed that the cultured cells grown on Millipore filters formed polarized monolayers with tight junctions. Monolayers exhibited a mean transepithelial resistance of 333.9 +/- 40.4 omega cm2. 3. Ca(2+)-mobilizing agents, A23187 (1 microM) or thapsigargin (0.01-1 microM), stimulated ISC while forskolin exerted little effect on the ISC. 4. Replacement of external Cl- by gluconate significantly reduced the ISC by 63% when stimulated by 0.1 microM thapsigargin. Residual ISC could be abolished (> 99%) by elimination of HCO3- from the bathing solution. 5. Basolateral addition of bumetanide (0.1 mM), ouabain (0.01 mM) and acetazolamide (45 microM) and apical addition of methyl isobutyl amiloride (MIA, 1-100 microM) all had inhibitory effects on the thapsigargin-stimulated ISC to various extents. 6. Substantial current inhibition could be obtained using 4, 4'-diisothiocyanatostilbene-2,2'-disulphonic acid (DIDS) and diphenylamine-2-carboxylate (DPC) in a concentration-dependent manner. 7. The K+ channel blocker barium (5 mM) was effective on both sides of the epithelium with a much larger effect on the basolateral side. 8. The inhibitory effects of acetazolamide, amiloride, MIA, DIDS and DPC on the thapsigargin-stimulated ISC were also observed when a Cl(-)-free solution was used. 9. The results provide evidence for Ca(2+)-stimulated HCO3- as well as Cl- secretion by equine sweat gland epithelium.

Sudoriferous acrosyringeal acantholytic disease. A subset of Grover's disease

Three selected cases of transient acantholytic dermatosis were studied because of their definitive correlation with sweating due to fever and/ or bed-ridden situations. Biopsy specimens were serially sectioned and acantholysis was found in the acrosyringium or traced to connect to the acrosyringium in all biopsy specimens. Carcinoembryonic antigen (CEA) and eccrine gland-specific monoclonal antibody, IKH-4, were positive in acantholytic cells. Electron microscopy revealed electron dense material filling the lumen of intraepidermal eccrine ducts. This material leaked into lateral intercellular spaces of the luminal cells, passing tight junctions. Marked edema and numerous lysosomes were reminiscent of those found when eccrine acrosyringium is formed in the embryo; this suggested that an occluded and damaged eccrine intraepidermal duct was being rebuilt via lysosomal digestion.

Scanning electron microscopy of the basal surface of the epidermis of human digits

The epidermal-dermal junction of the volar skin of human digits was examined by scanning electron microscopy (SEM). Fixed specimens obtained from cadavers were treated with 6 N NaOH to exfoliate the epithelium. The three-dimensional features of the basal surfaces were clearly visualized by SEM. Epithelial prolongations (intermediate and limiting ridges) protruded towards the dermis, and transverse ridges were visible between them. Nerve fibers and Schwann cells were aggregated around the sweat ducts on the intermediate ridges. Discoid structures were visible among the nerve fibers and Schwann cells. Examination by transmission electron microscopy of ultrathin sections of re-embedded specimens confirmed that the discoid structures were nerve endings that covered the Merkel cells. Minute projections were studded on the basal surfaces of basal keratinocytes. The projections in the intermediate ridges appeared to be villous, whereas the profiles of those in the limiting ridges resembled cobblestones. This morphological difference might be a reflection of function.

Differential regulation of adrenergic receptor development by sympathetic innervation

Rat sweat glands provide an interesting model system for a developmental study of adrenergic receptor expression because their sympathetic innervation undergoes a switch from a nonadrenergic to cholinergic and peptidergic phenotype. alpha 1B, alpha 2B, and beta 2 receptors are expressed in rat footpads; alpha 1 and beta 2 receptors are localized specifically to sweat glands, and alpha 2 receptors also are expressed in other tissues. alpha 1 and, to a lesser extent, beta 2 receptors decrease during development, whereas alpha 2 levels remain relatively constant. Decreased receptor expression is accompanied by the loss of alpha 1-stimulated inositol phosphate accumulation, but no change in beta-stimulated cAMP production. The number of alpha 1 and beta 2 receptors decreases after P21, when the sympathetic innervation no longer produces catecholamines. Neonatal sympathectomy causes a partial failure of alpha 1 downregulation, but has no effect on beta 2 or alpha 2 receptor levels. Therefore, at least two distinct mechanisms regulate development of adrenergic receptors in sweat glands. Innervation-independent processes control developmental expression of alpha 1, beta 2, and alpha 2 receptors, and an additional, innervation-dependent mechanism influences expression of alpha 1 receptors. Denervation at postnatal day 20, when the sympathetic innervation is cholinergic and peptidergic, results in retention of alpha 1 receptors, but cholinergic blockade begun at P20 does not. These results indicate that regulation of receptor expression in sweat glands is complex, and suggest that the innervation-dependent factors that decrease alpha 1 levels during development act through a nonadrenergic, noncholinergic mechanism.

Glycoproteins of the carcinoembryonic antigen (CEA) family are expressed in sweat and sebaceous glands of human fetal and adult skin

The carcinoembryonic antigen (CEA) family comprises a group of glycoproteins including the classical CEA, nonspecific cross-reacting antigens (NCA), and biliary glycoprotein (BGP). CEA glycoproteins have been identified in many glandular and mucosal tissues. In view of their putative role in cell adhesion, protein sorting, and signal transduction, CEA glycoproteins are thought to be involved in embryogenesis, architectual integrity, and secretory mechanisms of glandular epithelia. Since there are few data available on the expression of CEA-like proteins in human skin, the aim of this study was to immunohistochemically specify and localize the CEA glycoproteins in cutaneous adult and fetal glands using a panel of well-characterized antibodies. The secretory parts of eccrine sweat glands expressed CEA, NCA-90, and BGP, whereas apocrine glands remained unreactive for CEA glycoproteins. The ductal epithelia of both eccrine and apocrine glands contained CEA and NCA-90. Sebaceous glands were stained for BGP only. Electron microscopy of sweat glands showed CEA glycoprotein expression in cytoplasmic organelles and on microvilli lining the ductal surface. In sebaceous glands, BGP were demonstrated in small vesicles and along the cell membranes of differentiating sebocytes. Fetal development of cutaneous glands was associated with early expression of CEA glycoproteins. Additionally, mice transgenic for human CEA were shown to express CEA in sweat glands. The overall distribution of CEA glycoproteins in cutaneous glands was consistent with that in epithelia of other glandular tissues.

Histology and electron microscopy of fucosidosis of the skin. Subtle clues to diagnosis by electron microscopy

Fucosidosis is an autosomal recessive inborn error of metabolism in which fucose-containing glycolipids, glycoproteins, and oligo- and polysaccharides accumulate in tissues as a consequence of alpha-L-fucosidase deficiency. Since the detection of this entity in 1966 several cases have been described, but until now investigations of clinically uninvolved skin have not been performed. In this study we have investigated clinically normal skin obtained from a patient with fucosidosis and his healthy sister, by light and electron microscopy, to determine whether normal skin in this condition yields clues that may have prognostic relevance. We found "empty"- appearing storage vesicles in melanocytes, endothelial cells, sweat glands, and fibroblasts in the skin.

Sweat gland vacuoles in Unverricht-Lundborg disease: a clue to diagnosis?

There has been no reported pathologic abnormality outside the central nervous system in patients with Unverricht-Lundborg disease (ULD). We report membrane-bound vacuoles with clear contents in eccrine clear cells and dark cells in five of seven patients with ULD, as well as in one clinically unaffected sibling. Vacuoles were not seen in the biopsies of two patients and of eight controls with Lafora's disease. These findings, though not entirely specific, suggest that skin biopsy may serve as a diagnostic aid to give supportive evidence for ULD.

Morphology of sweat glands in determining time of death

This study demonstrates post-mortem autolytic alterations in the skin at cellular and subcellular levels and identifies parameters which may assist in determining the time of death in the first few hours post-mortem. Serial skin samples from the ventral surface of the arm were taken at intervals of 3, 6, 9 and 12 h after death in 29 subjects of various ages, with no signs of skin disease; causes of death were various. Three types of tests were performed: cytochemical (hematoxylin-eosin and alcian-PAS), immunohistochemical (S-100, CEA, Cytokeratin, ASM) and ultrastructural (electron microscopy). Electron microscopy proved useful for identifying transformations which were found to be specific for each chronological step considered: reduction of intracellular glycogen in clear cells and reduction of secretory granules in dark cells are typical signs of the first stage (3 h) after death; mitochondrial dilatation and rarefaction of cristae in clear and dark cells are typical of the second stage (6 h); rarefaction of microvilli in dark and clear cells is a sign of the last stage (12 h). Cytochemistry and immunohistochemistry supply useful information--not for all the chronological stage considered here, but for individual phases (3 h for hematoxylin-eosin and 6 h for alcian-PAS). However, it is particularly important to use the results from all such techniques simultaneously, so that the question of the exact time of death within the first 12 h post-mortem may be more accurately answered.

Dispersed cell culture of human sweat duct cells under serum-free conditions

Human eccrine gland duct cells were successfully cultured using a serum-free medium, K-GM medium. Eccrine sweat ducts were isolated from dispase treated skin specimens from palms or soles. After treatment of the isolated ducts with trypsin and EDTA, dispersed cells were cultured in K-GM medium. In primary cultures, small colonies were seen 3 to 4 days after inoculation. Then the cells rapidly proliferated and formed large colonies with a paving stone-like cell arrangement. During the culture, small dome shaped areas were sometimes formed in the centers of colonies. Cultures multiplied for a maximum of 7 passages. The plating efficiencies of the 1st to 6th passage cells were about 20% to 30%. Immunocytochemically, cultured cells were positively stained with anti-carcinoembryonic antigens, K8.37 and K8.13, but not with anti-S100 protein, anti-HLA-DR, 34 beta B4, or PKK3. An electron micrograph of the cultured cells showed a multilayer of flattened cells linked by desmosomes. These results indicate that the cultured cells possessed the staining properties compatible with those of the ductal portion of eccrine sweat glands. No contamination by other mesenchymal cells, such as fibroblasts, was seen during the culture.

Investigation of stimulus-secretion coupling in equine sweat gland epithelia using cell culture techniques

When sweat glands isolated from samples of horse skin were explanted and cultured under favourable conditions, they could exhibit cellular outgrowth. This growth could be maintained for 2–4 weeks and these primary cultures were then disaggregated and the resultant cell suspensions used to initiate epithelial cell lines. Secretion from intact equine sweat glands is regulated by beta 2-adrenoceptors and appears to be mediated by cyclic AMP, but there is evidence that calcium may also play a role. Adrenaline could increase the cyclic AMP content of the cultured cells and this response was mediated by beta 2-adrenoceptors. Adrenaline was also able to evoke a small increase in intracellular free calcium ([Ca2+]i) but the pharmacology of this response remains obscure. Adrenaline thus activates at least two potentially important second-messenger signalling pathways which have the capacity to interact, because adrenaline-evoked cyclic AMP formation was inhibited if [Ca2+]i was raised with ionomycin. The chloride permeability of mammalian epithelial cells characteristically rises during secretion, and adrenaline could increase chloride permeability in the cultured epithelia but the cells did not contain cyclic-AMP-dependent chloride channels and so this response was mediated by [Ca2+]i.

Demonstration of anionic sites in human eccrine and apocrine sweat glands in post-embedded ultra-thin sections with cationic colloidal gold: effect of enzyme digestion on these anionic sites

We localized anionic sites ultrastructurally in human eccrine and apocrine sweat glands with a poly-L-lysine-gold complex (cationic colloidal gold). Anionic sites were labeled by incubating Lowicryl K4M-embedded sections on droplets of cationic colloidal gold. In eccrine sweat glands, colloidal gold particles were restricted to the basolateral membrane of the secretory cells at low pH, whereas the luminal membrane did not react with the gold particles. Chondroitinase ABC digested these anionic sites. This indicates that chondroitin sulfate and/or dermatan sulfate constitutes anionic sites in the basal labyrinth of eccrine sweat glands. In apocrine sweat glands, the luminal membrane of the secretory cells showed strong reaction at low pH, whereas the contraluminal membrane did not show any reaction. Neuraminidase completely digested these anionic sites, which indicated that the anionic charge of the apocrine lumen was due to sialic acid. Differences in distribution and susceptibility to enzymes of anionic sites in cell membranes between eccrine and apocrine sweat glands may reflect functional differences between these glands. Dark cell granules in eccrine secretory cells were negative for the anionic sites when sections were labeled without any pre-treatment. However, pre-incubation of the grids on EGTA or deionized water unmasked the anionic sites on the dark cell granules. The positive staining after EGTA treatment was greatly decreased by reincubation with CaCl2. These results suggested that Ca blocked anionic sites in dark cell granules. Exposed anionic sites were digested with chondroitinase ABC. This indicated that chondroitinase ABC and/or dermatan sulfate composed the anionic sites in dark cell granules.

Schwannoma with sweat duct differentiation

We report a schwannoma with well differentiated ducts resembling cutaneous sweat ducts. The tumor presented as a painless mass near the left knee of a 41-year-old female. The mass had been present for many years. Some increase in size had been noticed over the previous 2 to 3 yr. The bulk of the tumor was composed of spindle cells with the appearance of Antoni A and Antoni B tissue. Rare mitotic figures were noted. In several areas of the tumor, numerous well-differentiated ducts were present. Most resembled normal cutaneous sweat ducts. In some areas, cystic dilatation of the ducts was present. Focal areas demonstrated poorly formed ducts and single cells with prominent nuclei and ample cytoplasm. Well formed ducts, poorly formed ducts, and single cells marked with AE 1/3 (keratin) and epithelial membrane antigen. The spindle cell proliferation marked for S 100 protein and vimentin. Sweat duct differentiation has not been reported previously in either benign or malignant schwannoma. Light and electron microscopic features of this tumor are presented.

Ultrastructure of the human anogenital "sweat" gland

A newly described type of cutaneous gland occurring in the human anogenital region was investigated in specimens from the vulva by electron microscopy. This gland, which is characterized by a long excretory duct opening at the skin surface, by a wide coiled secretory part with multiple lateral extensions in the form of diverticula and branches lined by a two-layered pseudostratified epithelium of myoepithelium, and by a luminal layer of tall columnar cells with conspicuous "snouts," could not be categorized as an eccrine, apocrine, or mammary gland. Electron microscopy confirmed its separate position by showing that the luminal layer of secretory cells with prominent cytoplasmic caps had elaborately folded lateral membranes, occasional canaliculi, and a large number of uniform electron-lucent to moderately electron-dense secretory granules as part of a probable merocrine secretion. The excretory duct showed a poorly developed cuticular border. This combination of ultra-structural features is alien to the other tubular cutaneous glands. The function of this anogenital "sweat" gland remains obscure, but the presence of these granules suggests a secretion product that is different from that of other cutaneous glands.

A transformed human epithelial cell line that retains tight junctions post crisis

The successful establishment of a postcrisis SV-40 T antigen transformed epithelial cell line, 1HAEo-, which retains tight junctions and vectorial ion transport, is described. Immunocytochemical analysis of 1HAEo- cells shows a defined pattern of cytokeratin staining and a characteristic pericellular localization of the adhesion molecule cellCAM 120/80, indicating the presence of junctional complexes. The presence of both tight junctions and desmosomes has been confirmed by electron microscopy. Cell monolayers have good transepithelial resistance measured in Ussing chambers. Cells increase chloride ion transport in response to addition of agents that raise either intracellular cAMP or calcium, measured either by 36Cl- efflux or whole-cell patch clamp. An increase in short-circuit current, in response to these agents, can be measured in Ussing chambers. The presence of a depolarization-induced outwardly rectifying 45 pS chloride channel has been demonstrated in single cell detached membrane patches. In addition, the cells have been found to express mucin mRNA. These cells therefore demonstrate that it is possible to select transformed cell clones with particular morphologic characteristics, i.e. the presence of tight junctions and cell polarity, which also retain useful epithelial cell-specific functions, including vectorial ion transport. They also provide a major resource for the study of the structure and function of human epithelia.

Eccrine syringofibroadenomatosis: a clinical and histologic study and review of the literature

A 56-year-old man had an 11-year history of a psoriasiform eruption of the palms, soles, and shins. An examination revealed well-demarcated patches and plaques of erythematous, fissured, and hyperkeratotic skin with focal erosions. There was no clinical evidence of ectodermal dysplasia. On histologic examination these lesions proved to be eccrine hamartomas that consisted of anastomosing cords and strands of cuboidal epithelial cells with well-formed ducts and a fibrovascular mucinous stroma. Eccrine ductal origin was indicated by histopathologic, histochemical, immunopathologic, and electron microscopic evaluation. These multiple palmoplantar eccrine hamartomas, unassociated with ectodermal dysplasia, represent a sporadic hamartomatous condition that is best designated as "eccrine syringofibroadenomatosis."

Immunohistochemical, morphological and functional changes in the peripheral sudomotor neuro-effector system in elderly people

Age-related changes in the human peripheral sudomotor neuro-effector system have been investigated in six 80-year-olds and six young adults. Histochemical and immunohistochemical studies on forearm skin biopsies showed diminished vasoactive intestinal polypeptide (VIP) and calcitonin gene related peptide (CGRP)-like immunoreactivity and a virtual absence of acetylcholinesterase in the elderly sudomotor nerve endings compared to the young. Reduced size of nerve bundles and decreased density of sympathetic nerve endings adjacent to the sweat glands of old people were shown by the neuronal marker, protein gene product (PGP 9.5), and by electron microscopy. Image analysis techniques were also used to demonstrate a marked regression in secretory coil size with age. Functional decrements accompanying the neurochemical and morphological changes in the neuro-effector system were measured in ten 80-year-olds by local quantitative nicotine axon reflex responses and compared with 12 young adults. These studies demonstrate marked regressive changes in both the nerve endings and target cells in old age and appear to express a significant loss of vigour in trophic interactions.

Dermal ridge development on the volar pads of the rat (Rattus norvegicus) and comparative study of pattern formation using inbred strains

The development of dermal ridges, ridge configurations, and volar pad contours was investigated in the volar skin of the rat (Rattus norvegicus). The ridged structures corresponding to the epidermal ridges of primates exist only at the epidermal-dermal junction in the rat. Dermal specimens were prepared by treatment with alkaline solution and examined by toluidine blue staining and scanning electron microscopy, together with histological sections. Differentiation of dermal ridges began on day 18 of gestation on the palm followed by the sole. Ridges increased in number with advancing age. The process was complete approximately 2-3 days after birth, and sweat ducts began to develop simultaneously. As dermal ridges present various configurational patterns on palmar interdigital pad III, pattern formation on this pad was inspected in fetuses of three inbred strains possessing different pattern types, and in the hybrid progeny derived from them. Patterns and pad forms appeared to be under genetic control. It was revealed that the ridge arrangements, i.e., whorls, triradii, comb-like patterns, and others, are closely related to the pad contours during the developmental period, as hypothesized in primates.

Human eccrine sweat gland. Expression of neuroglandular antigens and coexpression of intermediate filaments

Acrosyringium, duct and secretory epithelium as well as myoepithelial cells of human eccrine sweat glands have been characterized by different immunostaining patterns with mono- and polyclonal antibodies to a wide spectrum of tissue antigens. Using monoclonal antibodies to neuron-specific enolase (NSE) and melanoma-associated antigens (LS 59, HMB-45, NKI/C-3) the expression of neuroectodermal antigens in secretory coils was demonstrated. Myoepithelial cells were double-stained with polyclonal vimentin and monoclonal CAM 5.2 (against keratins nos. 8, 18, 19) antibodies.

Presence and localization of proteins immunologically related to erythrocyte protein 4.1 in human skin

Analogues of human erythrocyte protein 4.1 have been examined in the human skin by immunochemical techniques using anti-human erythrocyte protein 4.1 antibodies. Immunoblot analysis revealed that human epidermis contains 4.1-like proteins of 80 kDa and 78 kDa that cross react with anti-protein 4.1 antibodies. Analysis with immunofluorescence microscopy revealed that the plasma membrane of the human epidermal keratinocyte was stained intensively in the basal cells, whereas spinous cells were moderately stained. It is noted that eccrine sweat gland cells and ductal cells were also stained in the peripheral cytoplasma. Taken together, these results demonstrate that 4.1-like proteins are present in human epidermal keratinocytes, eccrine sweat gland cells and ductal cells. The present findings enable us to suggest that a membrane skeletal protein lattice might exist in these cells.