Pathologic S-phase in the cells of eccrine sweat glands and of hair follicles in psoriasis

1980 ◽  
Vol 268 (3) ◽  
pp. 257-260 ◽  
Author(s):  
Attila Galosi ◽  
Helmut Pullmann ◽  
Gerd Klaus Steigleder
2019 ◽  
Vol 50 (4) ◽  
pp. 335-342 ◽  
Author(s):  
Leilei Cao ◽  
Liyun Chen ◽  
Haihong Li ◽  
Zairong Wei ◽  
Sitian Xie ◽  
...  

2018 ◽  
Author(s):  
Yana G. Kamberov ◽  
Samantha M. Guhan ◽  
Alessandra DeMarchis ◽  
Judy Jiang ◽  
Sara Sherwood Wright ◽  
...  

AbstractHumans differ in many respects from other primates, but perhaps no derived human feature is more striking than our naked skin. Long purported to be adaptive, humans’ unique external appearance is characterized by changes in both the patterning of hair follicles and eccrine sweat glands, producing decreased hair cover and increased sweat gland density. Despite the conspicuousness of these features and their potential evolutionary importance, there is a lack of clarity regarding how they evolved within the primate lineage. We thus collected and quantified the density of hair follicles and eccrine sweat glands from five regions of the skin in three species of primates: macaque, chimpanzee and human. Although human hair cover is greatly attenuated relative to that of our close relatives, we find that humans have a chimpanzee-like hair density that is significantly lower than that of macaques. In contrast, eccrine gland density is on average 10-fold higher in humans compared to chimpanzees and macaques, whose density is strikingly similar. Our findings suggest that a decrease in hair density in the ancestors of humans and apes was followed by an increase in eccrine gland density and a reduction in fur cover in humans. This work answers longstanding questions about the traits that make human skin unique and substantiates a model in which the evolution of expanded eccrine gland density was exclusive to the human lineage.


Author(s):  
J. V. Briggman ◽  
J. Bigelow ◽  
H. Bank ◽  
S. S. Spicer

The prevalence of strands shown by freeze-fracture in the zonula occludens of junctional complexes is thought to correspond closely with the transepi-thelial electrical resistance and with the tightness of the junction and its obstruction to paracellular flow.1 The complexity of the network of junc¬tional complex strands does not appear invariably related to the degree of tightness of the junction, however, as rabbit ileal junctions have a complex network of strands and are permeable to lanthanum. In human eccrine sweat glands the extent of paracellular relative to transcellular flow remains unknown, both for secretion of the isotonic precursor fluid by the coil and for resorption of a hypertonic solution by the duct. The studies reported here undertook, therefore, to determine with the freeze-fracture technique the complexity of the network of ridges in the junctional complexes between cells in the secretory coil and the sweat ducts. Glands from a patient with cystic fibrosis were also examined because an alteration in junctional strands could underlie the decreased Na+ resorption by sweat ducts in this disease. Freeze-fracture replicas were prepared by standard procedures on isolated coil and duct segments of human sweat glands. Junctional complexes between clear cells, between dark cells and between clear and dark cells on the main lumen, and between clear cells on intercellular canaliculi of the coil con¬tained abundant anastomosing closely spaced strands averaging 6.4 + 0.7 (mean + SE) and 9.0 +0.5 (Fig. 1) per complex, respectively. Thus, the junctions in the intercellular canaliculi of the coil appeared comparable in complexity to those of tight epithlia. Occasional junctions exhibited, in addition, 2 to 5 widely spaced anastomosing strands in a very close network basal to the compact network. The fewer junctional complexes observed thus far between the superficial duct cells consisted on the average of 6 strands arranged in a close network and 1 to 4 underlying strands that lay widely separated from one another (Fig. 2). The duct epitelium would, thus, be judged slightly more "leaky" than the coil. Infrequent junctional complexes observed to date in the secretory coil segment of a cystic fibrosis specimen disclosed rela¬tively few closely crowded strands.


1970 ◽  
Vol 54 (3) ◽  
pp. 229-232 ◽  
Author(s):  
Becky B. Johnson ◽  
Robert E. Johnson

2017 ◽  
Vol 42 (5) ◽  
pp. 548-550
Author(s):  
Y. Saito ◽  
Y. Shimomura ◽  
R. Abe

1981 ◽  
Vol 240 (1) ◽  
pp. R44-R51 ◽  
Author(s):  
K. Sato ◽  
F. Sato

Pharmacologic responsiveness of the eccrine sweat gland has never been studied under well-defined in vitro experimental conditions. Using isolated cannulated single monkey palm eccrine sweat glands, the dose response to both cholinergic and alpha- and beta-adrenergic agents and the effects of various antagonists on agonists were studied. The maximal sweat rate was highest after stimulation with cholinergic agonists, was lower with the beta-adrenergic agonist, and was least with the alpha-adrenergic agonist. Each secretory response was inhibited by its specific antagonist. Attempts to demonstrate the spare receptor, if any, by means of preincubation of the glands with N-(2-chlorethyl)dibenzylamine (Dibenamine) were unsuccessful. From the hyperbolic dose-response curves the values for KA and KB, dissociation constants for agonists and antagonists, respectively, were thus tentatively estimated according to Clark's classical receptor theory. Schild plots for each agonist-antagonist interaction produced straight lines with slopes of near unity, indicating the adequacy of the methodology. It was concluded that the isolated eccrine sweat glands retain their pharmacologic viability in vitro and show responsiveness to cholinergic as well as both alpha- and beta-adrenergic stimulations.


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