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Biomedical subjects

B S Bhagavan

Publications and source records attributed to B S Bhagavan.

At least 37 records · Page 2Linked to original sources
PubMed1984

Comparison of estrogen-induced hyperplasia to endometrial carcinoma.

Use of exogenous estrogens has been associated with endometrial cancer in a number of case-control studies. This observed association could be biased as a result of frequent misclassification of estrogen-induced hyperplasia as endometrial cancer. To evaluate this possibility, pathology slides from 233 patients with a hospital diagnosis of endometrial cancer were reviewed independently by two pathologists. The hospital diagnosis was confirmed by both pathologists in 86% of the cases, indicating that the misclassification of hyperplasia as carcinoma is uncommon.

Adenocarcinoma↗
PubMed1982

The significance of bone and cartilage formation in malignant fibrous histiocytoma of soft tissue.

Malignant fibrous histiocytoma of soft tissues (MFH), a mesenchymal tumor of varied morphologic patterns and cell types, sometimes contains bone and cartilage. Such bony and cartilaginous elements in a pleomorphic MFH may pose a difficult diagnostic challenge. An MFH with bone and cartilage can be distinguished from extraosseous osteogenic sarcoma and chondrosarcoma on the basis of qualitative and quantitative features of the osseous and chondroid elements. Five cases of soft tissue MFH containing bone and cartilage reported here showed: 1) that the bony and cartilaginous elements are mostly metaplastic and tend to be in the pseudo-capsule or fibrous septa of the tumor; and 2) that the bony elements may show a zoning pattern with peripheral maturation similar to myositis ossificans. In a single case, there was a small amount of "tumor osteoid." However, this was focal and lacked the diffuse and finely divided or ribbon-like pattern generally associated with osteogenic sarcoma. The probability that MFH with bone and cartilage is less aggressive than soft tissue osteogenic sarcoma or chondrosarcoma underscores the importance of accurate histologic diagnosis of these tumors.

Adult↗
PubMed1982

Malignant fibrous histiocytoma of soft tissue with metaplastic bone and cartilage formation: a new radiologic sign.

The presence of bone and cartilage in some cases of malignant fibrous histiocytoma of the soft tissue as a microscopic finding has been reported previously but little note has been taken of the radiologic manifestations of these tumor elements. A series of five such cases with sufficient metaplastic osseous and cartilaginous elements to produce roentgenographic evidence of their presence is reported here. An additional two cases showed only histologic evidence of bone or cartilage formation. The reactive ossification tends to be peripheral in location, involving the pseudocapsule of the sarcoma or its fibrous septa. In three there was a zoning pattern with peripheral or polar orientation, strongly suggesting the diagnosis of myositis ossificans. The latter was the diagnosis considered radiologically in four of the five cases. Malignant fibrous histiocytoma with reactive bone and cartilage must be considered in the differential diagnosis of soft tissue masses with calcific densities, particularly when these occur in tumors of the extremities.

Adult↗
PubMed1982

Pseudoactinomycotic radiate granules in the lower female genital tract: relationship to the Splendore-Hoeppli phenomenon.

Splendore-Hoeppli phenomenon, the in vivo formation of eosinophilic radiate structures around microorganisms and biologically inert substances, may simulate actinomycotic sulfur granules and has been recognized in extragenital sites. In the lower female genital tract, the authors have noted these pseudoactinomycotic radiate granules (PAMRAGs) in both the presence and the absence of intrauterine contraceptive devices. To elucidate the nature and morphogenesis of PAMRAGs, the light microscopic morphologic features of PAMRAGs were studied by means of a battery of special stains. The absence of central branching filaments or diptheroid forms in PAMRAGs serves to distinguish them from true actinomycotic sulfur granules. Using the immunoperoxidase technique, the authors examined PAMRAGs for the presence of immunoglobulin, complement, and fibrin. Their studies showed that PAMRAGs contain neutral glycoproteins, lipid, and calcium with no demonstrable microorganisms, immunoglobulin, complement, or fibrin. The authors do not support the assertions of others that Splendore-Hoeppli radiate bodies are immune complexes derived from host serum proteins. They speculate that PAMRAGs of the genital tract are derived from host leukocytes that aggregate in response to the commonly present bacteria, parasites, or inert foreign bodies that initiate the Splendore-Hoeppli phenomenon and the morphogenesis of PAMRAGs.

Actinomycosis↗
PubMed1982

Intravascular bronchiolo-alveolar tumor (IVBAT): A low-grade sclerosing epithelioid angiosarcoma of lung.

Intravascular bronchiolo-alveolar tumor (IVBAT) is a rare and highly distinctive pulmonary tumor of disputed cellular nature. Both epithelial and endothelial differentiation of this neoplasm have been suggested. We have studied multiple nodules of IVBATs from three patients by light and electron microscopy and by immunohistochemical methods for Factor VIII-related antigen (FVIII RAG). Our light and ultrastructural studies are in essential agreement with the previous suggestion of the endothelial nature of the neoplasm and our demonstration of the presence of FVIII RAG in many of the tumor cells offers new evidence strongly supportive of their endothelial differentiation. We believe that IVBAT and a group of extrapulmonary tumors described as epithelioid hemangioendothelioma and endovascular papillary angioendothelioma are similar biologically indolent neoplasms of epithelioid and dendritic endothelial cells characterized by stromal sclerosis, intravascular spread, a low incidence of metastases and slow clinical evolution. Thus, we regard IVBAT as a low-grade sclerosing angiosarcoma of the lung.

Adenocarcinoma, Bronchiolo-Alveolar↗
PubMed1981

Characterization of rat colonic epithelial cell populations.

Colonic epithelial cells from male Sprague-Dawley rats were isolated by incubating everted colon with hyaluronidase suspended in Puck's saline F with an average cell yield of 120 x 10(6). These cells were fractionated by discontinuous Ficoll gradient and by short-term cell culture techniques. Centrifugation of isolated cells on discontinuous Ficoll gradient (15-35%) yielded populations differing in their proliferative activity. Additionally, a short-term cell culture technique was standardized to fractionate these cells according to their proliferating activity as judged by their DNA synthesis and thymidine kinase activity. Viability of these cells were judged by trypan blue exclusion, capacity to oxidize glucose and incorporation of precursors into protein DNA, RNA and glycoproteins. These fractionated cells were examined and identified by cytological studies. Cells showing proliferative activity sedimented at heavier regions of the Ficoll gradient, and the majority of these cells attached to the surface under conditions of short-term culture. Columnar mature absorptive cells and mucus-secreting goblet cells that showed very little proliferative activity sedimented at lighter zones of the Ficoll gradient and a major portion of these cells failed to attach by the cell culture method.

Animals↗
PubMed1981

Glycoprotein synthesis in colonic epithelial cells from rats.

Viable colonic epithelial cells from rats were isolated by a non-enzymatic procedure using EDTA. The isolated cells were fractionated by sedimentation through at 15% to 35% discontinuous Ficoll gradient to yield cells differing in proliferative capacity from three different density regions of the gradient. Glycoprotein synthesis of these fractionated cells was examined in terms of their ability to absorb and incorporate labeled glucosamine and fucose into trichloracetic acid precipitable material. Glycoprotein synthesis was highest among cells with intermediate densities, banding in the middle of the gradient (Fraction II). Cytomorphological examination showed that these cells were predominantly goblet type.

Animals↗
PubMed1981

Nephrogenic adenoma of the urinary bladder and urethra.

The histologic and ultrastructural features of nephrogenic adenomas of the urinary bladder and urethra were studied in multiple specimens obtained from eight patients. Three of these were studied by indirect immunofluorescence for Tamm-Horsfall uromucoprotein. The lesions are uncommon benign metaplastic proliferations of urothelium, occurring most frequently in males as small cystic, papillary, or nodular masses and most often presenting with hematuria. Typically the metaplastic tubules resemble nephronic tubules. A florid atypical and pseudoinfiltrative proliferation of these tubules may led to an erroneous diagnosis of adenocarcinoma. Ultrastructural features of proximal convoluted tubules were identified in some of the tubules, but resemblance to specific segments of distal tubules was less certain. The ultrastructural features combined with the absence of Tamm-Horsfall protein in tubular lumina or cells suggest a mesonephric rather than metanephric homology. The lesions are appropriately treated by transurethral resection or fulguration, but persistent lesions were present in three patients up to 18 yeas after initial treatment.

Adenoma↗
PubMed1981

Whipple's disease: morphologic and immunofluorescence characterization of bacterial antigens.

The bacterial etiology of Whipple's disease is generally accepted. However, the exact identity of the "Whipple bug" has remained elusive. Indeed, the isolation of several types of bacteria from different patients with Whipple's disease has caused some to speculate that Whipple's disease may have polymicrobial etiology. Our light and electron microscopic studies document the presence of bacilliform organisms lying free in the lamina propria of the duodenal mucosa. Intact and partially degraded bacterial organisms were seen in the phagosomes of macrophages. Indirect immunofluorescence studies demonstrated the presence of multiple bacterial antigens in the lamina propria as well as the macrophage granules. This profile of antigens is similar to the profile demonstrated in four other patients in two previous studies. The occurrence of similar profiles of bacterial antigens in the tissues of different patients with Whipple's disease suggests a single microorganism in the etiology of Whipple's disease. Because of the overlapping features of muciphages and Whipple's cells in the rectal biopsy material, the superiority and reliability of proximal small intestinal biopsy in preference to rectal biopsy are re-emphasized.

Adult↗
PubMed1981

Tamm-Horsfall uromucoprotein and the pathogenesis of casts, reflux nephropathy, and nephritides.

This chapter is an attempt to organize and summarize a diverse literature concerning Tamm-Horsfall uromucoprotein. Importance of examination of urine sediment for casts and diagnostic classification of casts have been discussed. Despite a lack of understanding of its biologic function, clinicopathologic study of T-HM has implicated it as a component of a variety of disease states. It binds a number of proteins, including those on surfaces of bacteria and viruses. It inactivates enzymes of those organisms, possibly by reacting with ionic cofactors, such as divalent metals. Ionic binding of monovalent cations (e.g., Na+) and repulsion of anions, such as Cl-, suggest a role for T-HM in renal salt and water balance. The combination of T-HM with ions, including H+, and other materials that enhance gel formation may indicate an ion-exchange function. Gel (cast) formation in the lower nephron, however, may produce obstruction, which, following calcification, infection, or inflammation, could go on to produce stones, increase scarring, and augment reflux nephropathy. Pathogenetic roles in autoimmunity and disorders of mucus metabolism have also been speculated on.

Adult↗
PubMed1981

The frozen-section autopsy.

A protocol for the rapid completion of autopsies using frozen sections was studied. The protocol was tested on 50 autopsy subjects, and the results compared with those from the standard autopsy protocol used on the same 50 cases. Cost, speed with which the reports could be completed, teaching value, and accuracy were compared; autopsy completed by frozen sections was superior in all four areas. There were 47 errors, none of which involved major disease processes. All but nine were errors of sampling and could be remedied by the more liberal sampling of tissues and the occasional supplementation with paraffin sections. The frozen-section autopsy protocol can replace the standard autopsy protocol in most cases. The rapid completion of the autopsy invites participation of the clinician and stimulates cooperation that benefits both the clinician and the pathologist.

Autopsy↗
PubMed1981

Tetracycline-associated fatty liver of pregnancy, including possible pregnancy risk after chronic dermatologic use of tetracycline.

Two cases of tetracycline-associated fatty liver of pregnancy are reported. In one, the history was negative for antibiotic use, yet autopsy revealed typical gross and microscopic bone fluorescence of tetracycline. Tissue extraction and chemical analysis showed qualitative evidence of tetracycline, whereas quantitation revealed 60 microgram/gm of wet bone tissue. Findings in our cases and in those from the literature indicate that the association of tetracycline use and fatty liver of pregnancy is even more common than has been suggested.

Adult↗
PubMed1980

Carcinoid tumors of the appendix.

Forty-six carcinoid tumors of the appendix, diagnosed in surgically resected specimens during an 11-year period (1965 to 1975) were reviewed to determine the features of metastasizing tumors. Of the carcinoid tumors of the appendix, 8.8% were found to metastasize to regional lymph nodes. The most reliable criterion of metastasizing tumors was the size of the primary tumor. Such tumors measured 2.0 cm or larger in greatest dimensions. Depth of invasion, extension to serosa, perineural involvement, histologic features, and location of the tumor relative to the length of the appendix were common to both the metastasizing and localized tumors. The surgical management of patients with carcinoid tumors of the appendix is controversial, ranging from a simple appendectomy to a more radical operative procedure. In the absence of distant metastases, it would appear that this group of patients with tumors 2.0 cm or more would require a right hemicolectomy rather than a simple appendectomy to accomplish removal of all disease-bearing tissue.

Adolescent↗
PubMed1980

Neoplastic and non-neoplastic mesothelial proliferations in pelvic lymph nodes.

Knowledge of gland-like inclusions in pelvic lymph nodes has existed since 1897. The histogeneses proposed to explain such alterations have included congenital rests, endometriosis, metastatic neoplasia, and mesothelial metaplasia. The correct interpretation of the lymph node involvement is important in order to institute appropriate therapy. In the present study, there were 12 examples of benign mesothelial inclusions found in routine sections from pelvic lymph nodes removed in the treatment of 337 cases of gynecologic cancer. In an additional 4 cases, an intraabdominal neoplasm was present. The variations in the histologic patterns are described as is the clinical course of the disease.

Adenocarcinoma, Papillary↗
PubMed1979

Pathways of urinary backflow in obstructive uropathy. Demonstration by pigmented gelatin injection and Tamm-Horsfall uromucoprotein markers.

The exact pathways of urinary reflux into the renal veins were studied in four cases of clinical obstructive uropathy and in 50 normal human cadaver kidneys. In the four clinical cases Tamm-Horsfall uromucoprotein was used as a marker for location of urine. Routine light microscopy and indirect immunofluorescence for Tamm-Horsfall uromucoprotein using rabbit antiserum showed tubular backflow up to the glomerulus. Dilated tubules filled with Tamm-Horsfall uromucoprotein ruptured into thin walled veins, forming tubulovenous anastomoses with extrusion of their contents into veins. The uromucoprotein was present in interlobar and arcuate veins with superimposed thrombosis and thrombophlebitis. Injection studies using pigmented gelatin in 45 normal cadaver kidneys and pigmented vinylite with corrosion casts in five additional kidneys complemented the clinical studies. Two types of urovascular communication were produced: the less frequent direct pyelovenous communication between a rupturing fornix and an adjacent small vein, and the more common indirect pyelovenous communication in which a ruptured fornix produced a sinus extravasate, which extended along the perivenous spaces of interlobar and arcuate veins. This extravasate gained access into the veins at points of rupture where venous tributaries joined the major veins in the renal medulla. The clinical implications of these tubulovenous and pyelovenous pathways of urinary reflux include backflow of whole urine and continued nephronic function in obstructive uropathy, "reverse backflow" of blood and hematuria, and a direct access for infectious agents into the circulation. These channels provide anatomic correlates for radiologic findings of extravasates and some backflow patterns of contrast material in pyelograms of clinical obstructive uropathy. The possible immunologic consequences of refluxing Tamm-Horsfall uromucoprotein gaining access to tissues and circulation are speculative.

Adult↗