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Biomedical subjects

J Alroy

Publications and source records attributed to J Alroy.

At least 145 records · Page 8Linked to original sources
PubMed1979

Intracytoplasmic lumina in bladder carcinomas.

Intracytoplasmic lumina were identified in neoplastic cells from four human and three canine "spontaneous" bladder carcinomas. They were also found in N-[4-(5-nitro-2-furyl)-2-thiazoly] formamide induced bladder carcinomas in rats as well as in cultured tumor cell lines derived from these experimental tumors. Intracytoplasmic lumina were readily recognized in 5 micrometer. paraffin embedded and 1 micrometer. epoxy embedded sections. Histochemically, intracytoplasmic lumina were strongly positive with PAS and alcian blue-PAS; mucicarmine stain was positive as unevenly distributed droplets. Ultrastructurally lumina were defined by a symmetric unit membrane; they displayed abundant pleomorphic microvilli, which contained prominent cytoskeletal elements. Step section electron microscopic study revealed continuity between intracytoplasmic lumina and the extracellular space in only one case of experimental bladder carcinoma; otherwise they appeared to be entirely encompassed within the cytoplasm. No instance of exocytosis in relation to intracytoplasmic lumina was found. Our observations suggest that intracytoplasmic lumina may be rather frequent in several forms of urothelial carcinoma. They appear to be predominantly but not invariably intracytoplasmic. The mechanism that may determine the development of continuity between intracytoplasmic lumina and the extracellular space and the adduced relationship between intracytoplasmic lumina and the process of secretion remain undetermined.

Animals↗
PubMed1979

Acinar cell carcinoma of the pancreas in a cat.

A feline pancreatic acinar cell carcinoma studied by light and electron microscopy was characterized by three growth patterns: acinar formation, colloid production and sheets of neoplastic cells. Ultrastructurally, the acinar origin of the tumor was determined by the presence of zymogen granules, some of which contained and released microfibrillar material.

Animals↗
PubMed1979

Ultrastructure of canine urinary bladder carcinoma.

Luminal and intraepithelial asymmetric unit membrane plaques were found in the urinary bladder urothelium of normal dogs. Tight junctions were found only at the apical poles of the luminal cells. In four dogs with spontaneous urinary bladder carcinomas the asymmetric unit membrane plaques were replaced by symmetric unit membrane. In the neoplastic luminal cells the tight junctions were partially attenuated. Invasive and metastatic neoplastic cells had some tight junction at the stromal interface. Some gap junctions were seen in the normal urothelium but not in the neoplastic cells. The amount of desmosomes in the neoplastic cells varied according to their direction of differentiation (transitional, squamous or glandular).

Animals↗
PubMed1978

Alterations of intercellular junctions in acinic cell carcinoma of the canine pancreas.

Intercellular junctions in spontaneous canine pancreatic acinic cell adenocarcinomas were compared to those in control canine pancreas. The neoplastic cells displayed proliferation and fragmentation of tight junctions and reduction in size and number of gap junctions. Marked decrease in desmosomal density was observed only in the poorly differentiated carcinoma. In the well differentiated carcinomas a few of the desmosomes were characteristic of those found in squamous cells. No quantatitive or qualitative differences in cell junctions were noted between primary and metastatic tumor.

Adenocarcinoma↗
PubMed1978

Isoantigens A, B and H in urinary bladder carcinomas following radiotherapy.

ABH tissue isoantigens were measured by the Specific Red Cell Adherence (SRCA) test in 66 surgical specimens of urinary bladder, including 53 transitional cell carcinomas, 2 squamous cell carcinomas and 11 controls. The SRCA test was strongly positive in 10 of 11 controls. ABH isoantigens were absent or equivocally present in 68 percent of noninvasive carcinomas (stage 0) and in 65 percent of invasive carcinomas. Clinical histories revealed that all patients with invasive carcinoma who had strongly positive SRCA test results had received prior radiotherapy to the bladder region. None of the patients with invasive bladder carcinoma with negative or weakly positive SRCA tests had been radiated. Histopathology of tumors in both groups was similar. Results of this retrospective study support the hypothesis that radiation may induce differentiation in tumors, possibly through an enhancement of Golgi apparatus function. The SRCA test should not be used as a predictor of the biological behavior of future recurrences in patients with bladder carcinoma who have received therapeutic radiation since radiation may produce "false positive" SRCA test results.

ABO Blood-Group System↗
PubMed1978

Desmosome ultrastructure and biological behavior of chemical carcinogen-induced urinary bladder carcinomas.

In the quantitative electron microscopic study, we examined the relationship of desmosomes to tumor invasiveness in chemical carcinogen (N-[4-(5-nitro-2-furyl)-2-thiazolyl]formamide)-induced urinary bladder transitional cell carcinomas in the Fischer rat. The number of a desmosomes per unit area of plasma membrane was significantly reduced in carcinomas. However, the percentage of cell surface area occupied by desmosomes was greater in carcinomas than in controls. This was accounted for on the basis of increases in desmosomal size, which result from squamous differentiation within the tumors. Areas of transitional cell differentiation and squamous differentiation demonstrated an equal capacity for invasiveness. Desmosomes were abundant in invading nests of tumor cells. These findings cast doubt on the validity of the concept of decreased intercellular adhesion as a prerequisite for tumor invasion, since strong interadhesion is probably a function of the area occupied by the intercellular junctions.

Animals↗
PubMed1978

An ultrastructural study of acinic cell carcinomas of the canine pancreas.

Four cases of spontaneous adenocarcinoma of the canine exocrine pancreas were studied by thin section and freeze-fracture electron microscopy. The neoplastic cells in all 4 cases were of acinar origin and showed many alterations of cytoarchitecture compared with normal acinar cells. In the neoplastic cells, zymogen granules varied in number and appearance and contained an abnormal secretory product characterized by 24-nm-thick microtubules. The nuclear volume and surface area and the nuclear cytoplasmic ratio were increased; although the nuclear pore density per nuclear surface area was significantly decreased, there was no change in the nuclear pore density per nuclear volume. There was a decrease in number and size of gap junctions; focal proliferation, fragmentation, and discontinuation of the tight junctions were also noted. The basal lamina (BL) of the neoplastic cells was discontinuous. The tumor microvasculature often appeared as sinusoids and had sparse discontinuous BL. Finally, the endothelium in both tumor and normal tissue contained "tubulo-reticular inclusions" (TRI) which simulated distemper virus and were located in the rough endoplasmic reticulum (RER) and the perinuclear cisternae.

Animals↗
PubMed1977

Freeze-fracture of monolayer cultures.

This paper describes a simple method for the freeze-fracturing of cells in monolayers or multi-layer tissue cultures. The method produces high quality replicas and is applicable to the study of virtually any tissue culture or organ culture system. It uses standard materials and equipment for both tissue culture and freeze-fracturing.

Cell Line↗
PubMed1977

Metal carcinogenesis: a study of the carcinogenic activity of solid metal alloys in rats.

The carcinogenic activity of seven metallic alloys was studied by implanting solid rods of each alloy in the gluteal muscles of Sprague-Dawley rats which were killed after twenty-four months. When the number of tumors in these rats was compared with the numbers in rats not operated on, in rats which had a sham operation, and in rats implanted with Silastic rods, no statistically significant differences in the incidences of the tumors in the several groups were found.

Alloys↗
PubMed1976

Cogan's syndrome: a systemic vasculitis.

Nonsyphilitic interstitial keratitis with vestibuloauditory dysfunction (Cogan's syndrome) is a rare clinical entity. We have reviewed 53 cases (including one of our own) of this disease. In 72 per cent of the affected patients there was an underlying systemic process, often a vasculitis. Ten per cent had fatal or near fatal aortic valvular disease, which has been shown to be amenable to surgical intervention. Other systemic manifestations have included congestive heart failure, gastrointestinal hemorrhage, adenopathy, splenomegaly, hypertension, musculoskeletal involvement and eosinophilia. The clinical course is extremely variable, ranging from months to over 15 years with a minimal five year survival of 28 per cent. Medical therapy with corticosteroids has been beneficial but has only limited effect on symptoms of vestibuloauditory dysfunction. Cogan's syndrome appears to be a manifestation of a systemic disorder which is often apparent only after long-term follow-up.

Adolescent↗
PubMed1975

Distinctive intestinal mast cell neoplasms of domestic cats.

By use of histologic, histochemical, and ultrastructural techniques a group of distinctive intestinal neoplasms of domestic cats, previously thought to arise from enterochromaffin cells, were redefined as mast cell neoplasms. Although these tumors differed histologically from the more typical visceral mast cell neoplasm of cats, ultrastructural and histochemical similarities between cells comprising both tumors were encountered. Differences in granule morphology and histochemical characteristics were, however, consistently demonstrated when the neoplasms were compared. The intestinal neoplasms are not associated with ulceration of the gastrointestinal tract unlike many mast cell tumors involving viscera. We suggest that the differences between the cells in the typical visceral and intestinal tumors confirm and extend the concept of the existence of morphologic and functionally heterogeneous populations of mast cells occurring in different anatomical locations of the body.

Animals↗