Ultrastructure of the developing fibrocartilage of the os penis of rat

Development of the fibrocartilage of the os penis of rat was studied by transmission electron microscopy. Prepubertal (0-4 weeks of development) and pubertal (4-8 weeks of development) males were examined. Effects of castration on the development of the fibrocartilage were also examined. During the first 0-4 weeks of development, cells in the primordium of the fibrocartilage became large and the cytoplasm had well-developed rough endoplasmic reticulum (rER) and many intermediate filaments. Collagen fibers increased markedly in amount in the extracellular matrix (ECM) during the period. For 4-6 weeks, when gonadal secretion of androgens increases, the cells developed into mature chondrocytes with lacunae. Collagenous bundles were pushed away from the lacunae, resulting in a characteristic appearance of this fibrocartilage. The cytoplasm of the mature chondrocytes of the fibrocartilage was characterized by many intermediate filaments, oil droplets, glycogen granules, and well-developed rER. At 6 weeks, calcification started on the cell membrane of the mature chondrocytes. At 8 weeks, a large part of the cartilage matrix was calcified. Matrix vesicles that originate from degenerated chondrocytes were found in the ECM of decalcified samples. In castrated males, cells of the primordium of the fibrocartilage ceased further development after castration. Intermediate filaments were still abundant in the cytoplasm and collagen fibers increased even after castration, but mature chondrocytes never differentiated. There were no signs of matrix vesicle formation, calcification, or cell degeneration in the fibrocartilage primordium. The developmental process of the fibrocartilage can be subdivided into two phases: collagenous matrix formation during the prepubertal period (0-4 weeks), and maturation of chondrocytes and calcification after puberty (4-8 weeks).     

Hair strangulation of the glans penis

This uncommon case of a partial penis amputation is presented to call attention to human hair as a potential source of injury in children and to demonstrate a successful two-stage repair for this interesting deformity.     

Immunohistochemical localization of metallothionein in developing rat tissues

Metallothionein (MT) is a cysteine-rich, low molecular weight protein inducible by heavy metal ions and various endogenous factors. Using an indirect immunofluorescent technique, we studied the localization of MT in developing rat tissues (kidney, small intestine, and liver). In kidney of the neonate and fetus, MT was found in both the cytoplasm and the nucleus of renal tubular epithelia. Localization of MT changed with shift of zonation in the renal cortex during development. Metallothionein was found mainly in the inner zone of the cortex but not in tubules of the neogenic zone on Day 4. Until Day 18, tubular cells containing MT were observed in a part of the cortex adjacent to the medulla, followed by a significant decrease in immunostaining by Day 27. In small intestine of the neonate, MT was localized predominantly in Paneth and goblet cells which play secretory roles. The number of goblet cells with strong immunostaining for MT was maximal on Day 27. In liver of 20-day fetuses and of 4-day-old neonates, both the cytoplasm and the nucleus of hepatocytes exhibited strong immunofluorescence. The intensity of MT staining diminished with development, and by 18-27 days after birth no immunofluorescence was observed in the nucleus. We further studied a possible association of MT with development by localizing MT in livers obtained from partially hepatectomized and laparotomized rats. Hepatectomy led to the appearance of MT not only in the nucleus and cytoplasm of hepatocytes but also in sinusoids and bile canaliculi. After laparotomy, MT immunofluorescence was observed only in the cytoplasm. The present results suggest a possible involvement of MT in cell proliferation and differentiation, as well as in transport and secretion of this metal-binding protein.     

Malignant fibrous histiocytoma of the glans penis: a case report

BACKGROUND: Malignant fibrous histiocytoma has been regarded as the most common sarcoma of older adults. However, recent opinion regards pleomorphic malignant fibrous histiocytoma as an undifferentiated high grade pleomorphic sarcoma not otherwise classifiable utilizing current techniques available in surgical pathology. Notwithstanding controversy regarding its nomenclature, malignant fibrous histiocytoma involving the penis is exceedingly rare, with only 4 cases previously described, to our knowledge. CASE: An uncircumcised 73-year-old male presented with a painless, granular, partially necrotic lesion beneath the penile foreskin. There was no history of sexually transmitted disease, constitutional symptoms or dysuria. Examination of penile shaft, testicles, spermatic cord and inguinal lymph nodes were unremarkable. Biopsy revealed a markedly pleomorphic sarcoma. Subsequent, partial penectomy revealed the same lesion with an adjacent area of squamous cell carcinoma in situ. CONCLUSION: Malignant fibrous histiocytoma remains a diagnosis of exclusion. The investigation requires extensive tumor sampling in search of areas of differentiation and a complete battery of immunohistochemical markers. Therapeutically important entities in the differential diagnosis that must be ruled out include other poorly differentiated sarcomas, sarcomatoid squamous cell carcinoma and desmoplastic melanoma.     

Immunohistochemical localization of collagens and fibronectin in human breast neoplasms

Forty four specimens from neoplastic, hyperplastic and normal human breast tissues were studied for localization of collagens and fibronectin. Affinity purified antihuman type I, III and IV collagens and antifibronectins were utilized by the indirect immunoperoxidase technique on fixed and paraffin-embedded sections. 86% of the cell cytoplasm of infiltrating ductal and 83% of the lobular cancers were positively stained for collagen type I and III. Collagen type IV, however, was detected in 100% of infiltrating ductal and 83% of lobular carcinomas. Focal cytoplasmic staining is a predominant feature for all antigens in the intraduct carcinoma while a diffuse pattern is encountered in the infiltrating types. Intact basement membranes in various lesions always stained for type IV collagen and showed variable staining for type III collagen and fibronectin. Epithelia of normal, benign, hyperplastic breast and most medullary carcinoma were negative for the three collagen types. Our results are in favour of the view that infiltrating breast carcinoma cells produce inappropriately the majority of collagens and inconsistently other proteins such as fibronectin.     

Histomorphology of the glans penis in Vespertilionidae and Phyllostomidae species (Chiroptera,Mammalia)

The penises of bats are taxonomically distinctive in size and shape. In addition, they are variable in microscopic anatomy, indicating that histomorphological studies of copulatory organs of bats may help understanding their successful reproductive strategies. We studied adult males of 13 species of vespertilionid and phyllostomid bats. Both families exhibited the basic structure of the vascular penis of mammals: the hydrostatic elements of the corpora cavernosa and the corpus spongiosum surrounding the urethra, as well as accessory cavernous tissue. Variation in the position and amount of the tissues were observed in these families. Vespertilionid bats have a small glans penis with abundant accessory cavernous tissue on the prepuce and a highly variable baculum. The baculum varied in size and morphology, even among congeneric species, such as the three Lasiurus species and the two Myotis species. Phyllostomid species possess no bacula, but vascular structures are present to produce penile stiffening, particularly on the glans. Variation in the microscopic anatomy of the phyllostomid prepuce was observed, for example, Artibeus species had accessory cavernous tissue surrounded by a tunica albuginea, but Carollia perspicillata had two bundles of striated musculature and some adipose tissue; abundant pigments were present in the prepuce of most species.     

Immunohistochemical demonstration of a 44-KD phosphoprotein in developing rat bones

Polyclonal antibodies against a 44-KD phosphoprotein (44K BPP) from rat bone were raised in rabbits, affinity-purified, and used as probes to study the protein's distribution in various types of developing bones from newborn rats. Three immunostaining procedures were applied utilizing indirect immunofluorescence, avidin-biotin-peroxidase complex, and avidin-gold complex with silver enhancement. All methods gave essentially identical and/or complementary results. Antigenicity for anti-44K BPP was detected in endochondral and membranous bone. In the latter, it was also demonstrated in the osteoid. In the woven bone of lower jaw, immunoreactivity for anti-44K BPP antibodies was found in fibroblast-shaped cells (pre-osteoblasts) that were between the bone trabeculae but not in direct contact with bony extracellular material. In addition to these presumed osteoprogenitor cells, osteoblasts as well as osteocytes were strongly stained; the cytoplasmic staining was associated with the Golgi apparatus. Occasionally immunoreactivity was detected in osteoclasts, but in these cells immunostaining was either diffusely spread in the cytoplasm or present only at sites of bone erosion. These findings support the hypothesis that the 44K BPP is a protein made by osteoblasts and is localized predominantly in bone. Furthermore, the protein appears to be expressed early in histogenesis of the bone-forming cells.     

Immunohistochemical study of collagens of the extracellular matrix in cartilage of Sepia officinalis

We used various anti-collagen antibodies to perform indirect immunofluorescent staining of cartilage sections from cuttlefish (S. officinalis). On ultrathin sections and collagen fibril preparations from the same tissue, we performed immunostaining with colloidal gold. The extracellular matrix (ECM) of S. officinalis cartilage reacted intensely and homogeneously with an antibody directed against type I-like collagen isolated from the cartilage of cuttlefish and with anti-rat type V collagen antibody. A weak reaction was observed with anti-fish and anti-chicken type I collagen antibodies, while no reaction was observed with anti-rat type I and anti calf type II collagen antibodies. Anti-chicken type II, anti calf type IX and type XI collagen antibodies reacted weakly with ECM, while stained cell bodies and cell processes reacted more intensely. A similar pattern of reaction was observed on cartilage section and isolated collagen fibrils prepared for electron microscopy. These findings suggest that ECM of cuttlefish cartilage may be composed of molecules similar to the type I, type V, type IX and type XI collagen molecules of vertebrates. Cephalopods have evolved a cartilage of structure and macromolecular organisation similar to that of vertebrate cartilage. However, the main molecular components of S. officinalis cartilage--type I-like and type V collagens--differ from those of vertebrate cartilage. We suggest that this type I-like collagen can be considered an initial step toward the evolution of type II collagen typical of vertebrates.     

Immunohistochemical study of neuropeptide Y-containing nerve fibers in the human clitoris and penis

The occurrence and distribution of neuropeptide Y in the human clitoris and penis was investigated by light immunohistochemistry. Neuropeptide Y-containing nerve fibers were detected in the tunicae of arteries and veins as well as among trabecular smooth muscle. The distribution pattern of the peptide was similar in both organs although a higher density of immunoreactive nerve fibers was detected in the penis. The immunolocalization of neuropeptide Y was also compared with that of neuron-specific enolase, a neuronal marker which labels the entire nerve network. It is suggested that neuropeptide Y is involved in the physiology of the penis and the clitoris, affecting vascular and nonvascular smooth muscle activity.     

Immunohistochemical observation of growth-associated protein 43 (GAP-43) in the developing circumvallate papilla of the rat

The distribution and development of growth-associated protein 43 (GAP-43)-like immunoreactivity (-LI) in the rat circumvallate papilla (CVP) were compared to those of protein gene product 9.5 (PGP 9.5)-LI. In the adult, thick GAP-43-like immunoreactive (-IR) structures gathered densely in the subgemmal region. Some of these further penetrated the apical epithelium and trench wall epithelium. At least two types of GAP-43-IR structures were recognized; taste bud-related and non-gustatory GAP-43-IR neural elements. Immunoelectron microscopy revealed that GAP-43-LI was localized predominantly in the Schwann cells, and a few axons displayed GAP-43-LI in the lamina propria. In the trench epithelium, GAP-43-LI was detected in the cytoplasmic side of the axonal membrane. Some intragemmal GAP-43-IR axons made synaptic-like contacts with taste bud cells. At least four developmental stages were defined on the basis of the changes in distribution of GAP-43-LI. In stage I [embryonic day (E) 16–17] GAP-43-IR structures accumulated at the lamina propria just beneath the newly-formed circumvallate papilla. In stage II (E18–19) GAP-43-IR nerve fibers began to penetrate the apical epithelium. In stage III [E20-postnatal day (P) 0] GAP-43-IR nerve fibers first appeared in the trench wall epithelium. Penetration of GAP-IR nerve fibers occurred in the inner trench wall epithelium first, and then in the outer trench wall epithelium. In stage IV (P1-) the distribution of GAP-43-LI was similar to that observed in the adult; but the density of GAP-43-LI was much higher than in adults. PGP 9.5-LI showed a similar distribution pattern to that of GAP-43-LI, except for round-shaped cells in the apical epithelium at the late embryonic stages, and in taste bud cells and intralingual ganglionic cells which lacked GAP-43-LI. The similarities in distribution patterns of GAP-43-LI and PGP 9.5-LI during the development and mature circumvallate papilla suggest that GAP-43 may be a key neuronal molecule for induction and maintenance of the taste buds.     

Immunohistochemical detection of interstitial collagens in bone and cartilage tissue remnants in an infant Peruvian mummy

We investigated the immunohistochemical presence of various collagen types in bone and cartilage tissue from an infant Peruvian mummy dating between 500 and 1000 A. D. which had been excavated at the necropolis of Las Trancas in the Nazca region in Peru. Following careful rehydration and decalcification of the tissue, the mummy tissue showed morphologically good preservation of the matrix, which could be shown to be composed of various collagen types in a typical pattern. Bone consisted of a collagen I matrix with a small rim of collagen III and V at the endosteal lining and a pericellular collagen V staining around osteocytic holes. In the hypertrophic cartilage of the epiphyseal growth plate, a typical pattern of collagen types II and X could be found. These observations provide evidence that in well-preserved mummy tissue the antigenic determinants of major matrix components are still adequately preserved for an immunohistochemical analysis. This technique may thus be a very helpful tool for the analysis of pathologic processes of historic bone tissue. It may also allow in certain circumstances a distinction between pseudopathologic tissue destruction and pathologic tissue alteration. © 1993 Wiley-Liss, Inc.