Eccrine adenocarcinoma of the footpads in 2 cats. (1/65)

Adenocarcinoma of sweat glands of the footpads was diagnosed in 2 cats. Clinical signs included lameness and swelling of multiple digits. Pulmonary metastasis was detected in one case. Diagnosis was based on histopathological and immunohistochemical findings. Eccrine adenocarcinoma should be included in the differential diagnosis of footpads lesions in aged cats.  (+info)

Histo-physiology of the scent-marking glands of the penile pad, anal pouch, and the forefoot in the aardwolf (Proteles cristatus). (2/65)

The scentmarking glands of the anal pouch, penile pad, and the forefoot of the aardwolf (Proteles cristatus) were studied by histological, histochemical, immunohistochemical methods, and by electron microscopy. The morphological observations are correlated with eco-ethological aspects of this nocturnal animal. In all studied regions there was a superficial layer of holocrine sebaceous glands and a deeper layer of apocrine scent glands; these two types of glands apparently function in concert. Only in the forefoot were additional tubular glands, resembling eccrine sweat glands found, which may improve the frictional capacities of the paw, while apocrine and holocrine glands serve scent-marking functions of the forefoot. Penile pad and anal pouch are exclusively scent marking organs. The secretion modus of the apocrine glands is both via exocytosis and apocrine mechanism. Homogeneous apical, secretory granules, which contain glycoproteinaceous material, represent evidence for exocytosis. In the anal pouch, additional variably sized granules contain endogenous pigments which are probably responsible for the brownish coloration of the secretory product of the male animals. Variable heights of the glandular cells, frequent apical tall protrusions as well as pinched-off pieces of cytoplasm in the glandular tubules support the concept of an apocrine secretion in the scent glands. The immunohistochemical staining pattern of actin points to the involvement of actin filaments in the pinching-off process of the apical cell protrusion, which does not contain any cell organelles. The variable actin staining patterns suggest a dynamic process during which actin filaments form a ring or sheet at the basis of the pinching-off bleb. Proliferative and apoptotic phenomena show no preference for active and inactive glandular cells suggesting that replacement of cells occurs independently of the functional status of the glands.  (+info)

Function of human eccrine sweat glands during dynamic exercise and passive heat stress. (3/65)

The purpose of this study was to identify the pattern of change in the density of activated sweat glands (ASG) and sweat output per gland (SGO) during dynamic constant-workload exercise and passive heat stress. Eight male subjects (22.8 +/- 0.9 yr) exercised at a constant workload (117.5 +/- 4.8 W) and were also passively heated by lower-leg immersion into hot water of 42 degrees C under an ambient temperature of 25 degrees C and relative humidity of 50%. Esophageal temperature, mean skin temperature, sweating rate (SR), and heart rate were measured continuously during both trials. The number of ASG was determined every 4 min after the onset of sweating, whereas SGO was calculated by dividing SR by ASG. During both exercise and passive heating, SR increased abruptly during the first 8 min after onset of sweating, followed by a slower increase. Similarly for both protocols, the number of ASG increased rapidly during the first 8 min after the onset of sweating and then ceased to increase further (P > 0.05). Conversely, SGO increased linearly throughout both perturbations. Our results suggest that changes in forearm sweating rate rely on both ASG and SGO during the initial period of exercise and passive heating, whereas further increases in SR are dependent on increases in SGO.  (+info)

The role of androgen receptors in the clinical course of nevus sebaceus of Jadassohn. (4/65)

Nevus sebaceus of Jadassohn (NSJ) is a benign, congenital hamartoma that often presents at birth, appears to regress in childhood, and grows during puberty, suggesting possible hormonal control. We studied 18 cases of NSJ from children and adults for immunohistochemical evidence of androgen receptor expression. The lesions were evaluated for location and pattern of immunostaining, and these findings were compared between age groups, sexes, and to androgen receptor expression in normal skin. Androgen receptor positivity was seen in the sebaceous glands, in eccrine glands with and without apocrine change, and rarely in keratinocytes in the sebaceous nevi. There were no significant differences in staining location or pattern between the age groups or sexes. Normal skin showed similar staining in the sebaceous glands but did not show staining of the eccrine glands or keratinocytes. Androgen receptors are present in all epithelial components of NSJ, but there is no change in androgen receptor expression during puberty.  (+info)

Skin morphological changes in growth hormone deficiency and acromegaly. (5/65)

OBJECTIVE: To evaluate the histomorphology of skin and its appendages, especially eccrine sweat glands, in patients with GH disorders, because reduced sweating ability in patients with growth hormone deficiency (GHD) is associated with increased risk of hyperthermia under stressed conditions. DESIGN AND METHODS: A skin biopsy was obtained from 17 patients with GHD treated with GH, five patients with untreated GHD, 10 patients with active acromegaly and 13 healthy controls. RESULTS: The sweat secretion rate (SSR) was significantly decreased in both the untreated (median 41 mg/30 min, range 9-79 mg/30 min) and the GH-treated (median 98 mg/30 min, range 28-147 mg/30 min) patients with GHD compared with that in controls (median 119 mg/30 min, range 90-189 mg/30 min; P=0.001 and 0.01 respectively). Epidermal thickness was significantly decreased in both untreated (median 39 microm, range 28-55 microm) and GH-treated patients with GHD (median 53 microm, range 37-100 microm), compared with that in controls (median 66 microm, range 40-111 microm; P<0.02). A statistically non-significant tendency towards thinner epidermis (median 59 microm, range 33-83 microm) was recorded in acromegalic patients (P=0.08) compared with controls. There was no significant difference in the area of the sebaceous glands in the biopsies between the three groups and the controls. The area of eccrine sweat gland glomeruli was significantly decreased in the untreated patients with GHD (median 16407 microm2, range 12758-43976 microm2) compared with that in controls (median 29446 microm2, range 13511-128661 microm2; P=0.03), but there was no significant difference between the GH-treated patients with GHD and controls. CONCLUSIONS: We conclude that GH, either directly or via IGF-I, may have both a structural and a functional effect on human skin and its appendages, and that patients with GHD have histomorphological changes in skin compared with controls. Importantly, these changes are not fully reversed despite long-term and adequate GH treatment in patients with childhood onset GHD.  (+info)

Requirement of NF-kappaB/Rel for the development of hair follicles and other epidermal appendices. (6/65)

NF-kappaB/Rel transcription factors and IkappaB kinases (IKK) are essential for inflammation and immune responses, but also for bone-morphogenesis, skin proliferation and differentiation. Determining their other functions has previously been impossible, owing to embryonic lethality of NF-kappaB/Rel or IKK-deficient animals. Using a gene targeting approach we have ubiquitously expressed an NF-kappaB super-repressor to investigate NF-kappaB functions in the adult. Mice with suppressed NF-kappaB revealed defective early morphogenesis of hair follicles, exocrine glands and teeth, identical to Eda (tabby) and Edar (downless) mutant mice. These affected epithelial appendices normally display high NF-kappaB activity, suppression of which resulted in increased apoptosis, indicating that NF-kappaB acts as a survival factor downstream of the tumor necrosis factor receptor family member EDAR. Furthermore, NF-kappaB is required for peripheral lymph node formation and macrophage function.  (+info)

Evidence for sodium-coupled acid-base transport across the basolateral membrane of the reabsorptive duct of the human eccrine sweat gland. (7/65)

Intracellular pH was measured in isolated nonperfused ducts of human eccrine sweat glands in vitro to investigate basolateral acid-base transport mechanisms. Bath sodium removal led to a bicarbonate-independent, 4-acetamido-4'-isothiocyanatostilbene-2,2'-disulfonic acid insensitive acidification. The recovery of this acidification was ethylisopropyl amiloride sensitive, suggestive of basolateral sodium:hydrogen exchange. Whereas bath chloride removal led to a small acidification this was not 4-acetamido-4'-isothiocyanatostilbene-2,2'-disulfonic acid sensitive and its causes remain unclear. Elevation of bath potassium to depolarize the basolateral membrane led to a small alkalinization but this was not mimicked by addition of barium or chloride removal. As chloride removal and barium addition would be expected to cause larger depolarizations than potassium elevation these observations do not support a major role for electrogenic acid-base transport. In conclusion, although this study does not support a major role for electrogenic acid-base transport, it has demonstrated the basolateral presence of sodium-coupled acid-base transport in the reabsorptive duct of the human eccrine sweat gland, which most likely represents a sodium:hydrogen exchanger involved in regulation of intracellular pH.  (+info)

Histochemical and immunohistochemical markers for human eccrine and apocrine sweat glands: an aid for histopathologic differentiation of sweat gland tumors. (8/65)

Apocrine and eccrine sweat glands are distinct in function, although they are closely related to each other developmentally and morphologically. In certain sweat gland tumors, it is difficult to differentiate between eccrine or apocrine sweat glands. Therefore, this paper reviews histochemical and immunohistochemical markers to differentiate apocrine and eccrine sweat glands with the aim of better understanding the structural and functional characteristics of these sweat glands. Specific markers for apocrine sweat glands are as follows: neuraminidase sensitive anionic sites detected by cationic colloidal gold at pH 2.0, and mitochondrion-like secretory granules that have epidermal growth factor-like antigenicity. The following antibodies react with apocrine sweat glands but not with eccrine sweat glands; the antibodies raised against 70 kDa glycoprotein purified from human milk fat globule membranes, and HMFG-1 (1.10.F3) monoclonal antibody produced by immunizing mice with defatted human milk fat globule membranes. Markers for eccrine sweat glands are as follows: dark cell granules that have chondroitinase ABC sensitive anionic sites detected by cationic gold at pH 2.0 after pretreatment with EGTA, and intercellular canaliculi with high activity of alkaline phosphatase. CEA and GCDFP-15 are expressed in both eccrine and apocrine sweat glands. Anti-EMA monoclonal antibody (E29) stains both eccrine and apocrine sweat glands.  (+info)