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Biomedical subjects

Y Dayal

Publications and source records attributed to Y Dayal.

At least 91 records · Page 5Linked to original sources
PubMed1980

Lymphocyte cytotoxicity of patients developing multiple primary melanomas.

A study of cellular immunity was conducted, with particular attention to natural killer cell mediated in vitro cytotoxicity in 6 patients who had two or three primary melanomas (2 patients presenting synchronously with multiple primaries and additional melanomas subsequently developing in 4). All 6 patients were reactive to one or other recall skin test antigens (PPD, streptokinase streptodornase (SK-SD), monilia, mumps) and DNCB skin testing. All exhibited natural killing against melanoma and nomelanoma tumor target cells when examined in the 3H proline microcytotoxicity test with unfractionated as well as natural killer cell enriched (Fc receptor positive cells recovered as Fc receptor rosettes) lymphocyte fractions. None of the 4 patients who subsequently had additional primary tumors was found to lack in mature T or natural killer cell mediated cytotoxicity at the time of the development of additional primaries. Two melanoma cell lines were established from two separate primary tumors in 1 patient and in vitro cytotoxicity assays were performed with that patient's lymphocytes (unfractionated, T enriched, and natural killer cell enriched fractions) against these two lines. While the first melanoma cell line was consistently sensitive to lysis by all three lymphocyte fractions, the other cell line showed no sensitivity either for natural killing or for T enriched lymphocyte mediated lysis at any effector to target ratio. These results suggested that in vitro natural cytotoxicity was not translated into any substantive immunoprotective role in the development of multiple primary tumors and that the two separate melanoma cell lines from the same patient were antigenically hererogenous. Antigenic heterogeneity between different primary tumors may explain the lack of immunity against such development of multiple tumors of the same histology.

Antibody-Dependent Cell Cytotoxicity↗
PubMed1979

Immunocytochemical localization of calcitonin-producing cells in a strumal carcinoid with amyloid stroma.

A nonfunctioning strumal carcinoid arising in a 49-year-old woman was studied by histochemical and immunocytochemical techniques. All tumor cells, irrespective of their architectural arrangement, showed properties of neuroendocrine-programmed cells, without any evidence of thyroid follicular cell differentiation. Foci of calcitonin-producing C-cells were demonstrable by immunocytochemical technique and were closely associated with areas of amyloid stroma of the tumor. Efforts at localization of insulin and gastrin within the tumor cells gave negative results. While the results in the present case offer additional support for an APUD cell origin of strumal carcinoids, the presence of the calcitonin-producing C-cells within the tumor raises interesting histogenetic possibilities as to whether these lesions are derived from C-cells or represent an ovarian carcinoid with foci of C-cell differentiation.

Amyloid↗
PubMed1978

Immunocytochemical diagnosis of alpha-1-antitrypsin deficiency.

Eight cases of liver disease associated with alpha-1-antitrypsin deficiency are described. Six of the cases, including the only childhood case, showed no evidence of lung disease. An occult but variable clinical course is defined in this disorder. A spectrum in the severity of tissue change was noted, and in some instances, extensive liver disease was correlated with relatively minor derangement in liver function. While this form of liver disease is uncommon, it should be included in the differential diagnosis of adult liver disease. Screening for alpha-1-antitrypsin globules in periodic acid-Schiff stained liver tissue sections should be considered in certain cases of cryptogenic liver disease in adults, particularly when advanced disease presents suddenly, where micronodular (portal) cirrhosis is unrelated to excessive alcohol use, or where tissue changes exceed those anticipated from serum biochemical abnormalities. In most of these cases, tissue findings from liver biopsy or autopsy, rather than clinical suspicion, led to the diagnosis. The availability of a simple and reliable immunoperoxidase technique, applicable to routinely processed tissue samples, allowed for rapid and specific diagnosis in all cases. This immunocytochemical method has proven its usefulness in the prospective and retrospective tissue diagnosis of alpha-1-antitrypsin deficiency and associated liver disease.

Adult↗
PubMed1978

Gastrin-producing cells in ectopic gastric mucosa of developmental and metaplastic origins.

Immunocytochemical techniques using antigastrin antibody were employed to localize G cells in ectopic gastric mucosa of metaplastic and congenital origins and to compare their distribution with that in normal gastric mucosa. Five examples of Barrett's esophagus, 8 Meckel's diverticula, and 2 small bowel duplications were studied. Although G cells were absent in the gastric mucosa from all cases of Barett's esophagus, four Meckel's diverticula and one small bowel duplication contained G cells. In all instances of congenitally derived ectopic gastric mucosa where G cells were demonstrable, the gastric mucosa showed areas of antropyloric differentiation, whereas in the remaining cases the ectopic gastric mucosa was exclusively of the body-fundic type. It is concluded that the presence of G cells within ectopic gastric mucosa of Meckel's diverticula and small bowel duplications in foci of antropyloric differentiation reflects their developmental origin, whereas the absence of G cells in Barrett's esophagus is in keeping with its metaplastic derivation.

Choristoma↗
PubMed1977

Experimental pulmonary nocardiosis in monkeys.

The study describes an easy and reproducible technique of producing pulmonary nocardiosis in monkeys, yielding consistent morbidity and mortality results. Introduction of the fungal suspension into the lower canaliculus, with or without debridement of the canalicular epithelium, produced fatal pneumonitis in 1-2 weeks. Specificity of the lesions was determined by demonstration of Nocardia in tissue sections and in culture.

Animals↗
PubMed1977

Antropyloric G-cell hyperplasia in hypercalcemic rabbits bearing the VX2 carcinoma.

The number of distribution and the numbers of G cells in the antropyloric region of the rabbit stomach were mapped employing immunoperoxidase localization and morphometric quantitation and compared to similar analyses in hypercalcemic rabbits bearing the VX2 carcinoma. In normal animals, G cells were confined to the lower third of the antropyloric mucosa, where they were randomyly distributed within the mucosal glands. In contrast, tumor-bearing animals showed an extension of these cells into the middle third of the antropyloric mucosa. The absolute counts of G cells in control rabbits were 5.3 +/- 0.78 (mean +/- SE) per unit area, while those in hypercalcemic tumor-bearing rabbits were 11.9 +/- 0.46, a statistically significant increase. It is concluded that rabbits bearing VX2 carcinoma have G-cell hyperplasia.

Animals↗
PubMed1976

Dictyoma.

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Child, Preschool↗
PubMed1976

Histiocytosis X: a case report.

The rare disease entity of histocytosis X is presented. Features of unusual interests in the present case were the bilateral exophthalmus as the presenting sign, fever, ottorhoea and involvement of lung and long bones.

Child, Preschool↗
PubMed1976

Experimental intraocular nocardiosis.

We attempted to produce intraocular nocardiosis in rabbits. The clinical features and evolution of the disease and the role of corticosteroids was observed. N. asteroides suspension when injected into the anterior chamber produced a self limited nodular iridocyclitis. Local or systemic corticosteroids produced a severe anterior uveitis and progressive endophthalmitis. The organisms could be demonstrated from aqueous smears at the time of enucleation. When the suspension was injected into the vitreous cavity, it produced endophthalmitis. Local or systemic corticosteroids administration suppressed the anterior uveal inflammation and produced a purulent subconjunctival granuloma.

Animals↗
PubMed1975

Human pulmonary dirofilariasis. A case report and review of the literature.

A case of pulmonary dirofilariasis in a 48-year-old woman is presented. This rare pulmonary disorder is caused by Dirofilaria immitis, the canine heartworm. A review of the literature revealed 40 documented cases, most of which have occurred in the United States within the past 10 years. The incidence of pulmonary dirofilariasis appears to be increasing; thus, this entity represents an important zoonosis and indicates a need for familiarity with the pathologic features of the lesions and the morphologic characteristics of the worm.

Adult↗