Skin and superficial fascia of the foot.

The authors provide a brief review of the structure of the skin in general and the specializations of the plantar skin and superficial fascia. This review is intended to provide a basis from which the reader can interpret any relevant data in other papers on anatomy and to direct the reader to a variety of more detailed references.

Functional anatomy of the skin.

The skin is one of the best examples in the body for illustrating the correlation of form with function. Instead of looking at it from the viewpoint of its organization, this article takes each function and matches it with the cells meeting that need: keratinocytes for durability and cohesion for mechanical protection; epidermal intercellular substances to form an inpermeable barrier; melanocytes for ultraviolet protection; Langerhans cells for immune response; Merkle cells for sensation; hair follicles, sweat glands, extensive vascular supply, and adipose tissue for thermoregulation; and free and encapsulated nerve endings for sensation.

Secretion of polyalbumin receptors in vitro.

The nature of hepatitis B surface antigen (HBsAg)-associated receptors for polymerized human serum albumin (pHSA-R) and their relationship to hepatitis B e antigen (HBeAg) and human serum proteins have not been defined. We studied by radioimmunoassay and by electron microscopy HBsAg-associated pHSA-R secreted in vitro by a human hepatocellular carcinoma cell line (PLC/PRF/5) and by mouse 3T3 fibroblasts after transfection with cloned hepatitis B virus (HBV) DNA (4.10 cells). PLC/PRF/5 cells expressed only HBsAg, whereas 4.10 cells secreted also HBeAg. There was no significant difference in the production of HBsAg, HBeAg, and pHSA-R when the cells were cultured in the presence or absence of fetal calf serum. Secretion of pHSA-R by the two cell lines for a given amount of HBsAg was equal irrespective of the presence or absence of HBeAg. Supernatants from both cell lines grown in serum-free medium did not contain any Clq or albumin when tested by immunodiffusion. The ability of a transfected mouse cell line to produce HBsAg with pHSA-R activity strongly suggests that pHSA-R is coded by the HBV genome and does not depend on the presence of human serum proteins. In addition, our findings fail to demonstrate any correlation between HBeAg production and pHSA-R.

Ultrastructure of human penile erectile tissue in patients with abnormal norepinephrine content.

Past studies of the alteration of nerve morphology of penile erectile tissue in men with impotence using light and histofluorescent techniques have been inconclusive. We evaluated the ultrastructure of erectile tissue of five men; the content of the neurotransmitter norepinephrine in this tissue was also known. Our results show that in nerve fibers of men whose penile tissue samples displayed very low norepinephrine content, nerve fibers were extremely sparse. In two men with insulin dependent diabetes, alteration of the intracellular caveolae, glycogen, and microfilaments of smooth muscles were found. In addition, in these patients, there was an increased amount of cell surface coat material. In diabetic patients, these changes may translate into biomechanical alterations of the smooth muscle function within the erectile tissue.

Isolation and culture of human endometrial glands.

A simple method for isolation of glands from human endometrium has been developed. The procedure involves collagenase digestion of the endometrial tissue and filtration through sieves of various pore sizes. Isolated glands retained on the sieves were washed and collected in culture dishes. Tubular organization of the isolated glands was ascertained by examination of the preparations under inverted microscope and light microscopy of stained sections. The appearance of the glands was found to reflect different functional states of the endometrium and, possibly, to reveal abnormalities. Growth of monolayers of epithelial cells derived from the glands was observed within 24 h of culturing. Electron microscopy of the cells in 7-day monolayer preparations from both proliferative and secretory endometrium revealed the characteristic features of human endometrial epithelial cells, viz. presence of microvilli and desmosome-like junctions. Nuclear bodies were observed in cells derived from both types of endometrium.

Effect of testosterone on development of the lumen in seminiferous tubules of the rat.

Although systemically administered testosterone can effect the postnatal maturation of elements in the seminiferous tubule in hypophysectomized rats and mice, it does not elicit the same degree of development which occurs in normal control animals. In view of reports of precocious spermatogenesis in androgen secreting Leydig cell tumors, the present study was designed to determine if high local levels of testosterone accelerate development of the seminiferous tubules. Testosterone pellets were inserted under the tunica albuginea of the right testis of 7 day old rats. At 17, 23 and 28 days of age development of the seminiferous tubules, as judged by the formation of tubule lumens, was more extensive in the treated testes than in contralateral and sham operated controls. Tubule diameters were not necessarily correlated with lumen formation. This study demonstrates that high local levels of testosterone accelerate seminiferous tubule development in the rat and indicates that tubule diameter may not be a valid basis for estimating development of the testis. It is suggested that testosterone exerts this effect through its actions on the Sertoli cells.

The effect of 5-bromodeoxyuridine on the postnatal development of the rat testis.

The effects of 5-bromodeoxyuridine (BrdU) on postnatal testicular development were studied in rats treated on the second, third and fourth days of life. Testes were removed for study at 5, 15 and 35 days of age. Body weights and diameters of seminiferous cords and tubules were significantly less in the treated than control animals. At 15 days of age fewer pachytene spermatocytes were present in treated animals. At 35 days of age the testes of treated animals contained fewer canalized cords. Spermatids exhibited an altered distribution of chromatin material, contained less agranular endoplasmic reticulum and fewer mitochondria, and had not yet developed tails. Sertoli cells and Leydig cells of treated animals contained less agranular endoplasmic reticulum and more lipid droplets than the normal.

Dependence of Sertoli cell maturation on the pituitary gland in the mouse.

Postnatal development of the Sertoli cell population was studied in testes taken from newborn mice and implanted into the testes of normal hypophysectomized and testosterone-treated hypophyturation of the Seroti cell complement of each specimen was judged by two criteria: (1) the proportion of Sertoli cells exhibiting a nucleolonema; (2) the prevalence of specialized inter-Sertoli cell junctions. In these respects implants recovered from normal hosts did not differ from sibling controls of the same age. Sertoli cells in implants recovered from hypophysectomized hosts retained the features observed in newborn controls, indicating that maturation of the Sertoli cells is dependent on normal pituitary function. Implants recovered from testosterone-treated hypophysectomized hosts exhibited a degree of Sertoli cell development intermediate between those recovered from the other two host categories.