Biomedical subjects

G S Zaatari

Publications and source records attributed to G S Zaatari.

27 records · Page 2Linked to original sources

PubMed1984

Thymoma: an immunohistochemical study.

Four thymomas, two from patients with myasthenia gravis, were studied using a panel of monoclonal antibodies. Almost all the associated lymphocytes were T-cells with the common thymic lymphocyte phenotype, suggesting that the neoplastic epithelium can provide a microenvironment that retains or perhaps attracts immature T-cells. HLA-Dr antigens were expressed by some of the epithelial cells and many of the lymphoid cells in the perivascular space. The Leu-7 antigen was present on a subset of epithelial cells and had a highly variable expression in different thymomas. The percentage of lymphocytes bearing the OKT8-defined antigen appeared to be lower in patients with myasthenia gravis, while the expression of other markers did not appear to be consistently or significantly different. There did not appear to be marked differences in the lymphocyte subpopulations of thymomas with different morphology, and there was no evidence of differentiation of the thymomas into cortical and medullary areas.

Adult↗

PubMed1984

Subcutaneous hyphomycosis caused by Scytalidium hyalinum.

Scytalidium hyalinum is a hyaline species of the genus Scytalidium. It first was described as a cause of skin and nail infection in humans. In this report, the authors describe the first case of subcutaneous hyphomycosis with multiple cyst formation caused by this fungus. The patient is a 54-year old man who has Reiter's syndrome, liver cirrhosis, and coronary artery disease. He was receiving azathioprine and prednisone for arthritis. The pathology, mycology, and clinical course are discussed.

Cysts↗

PubMed1983

Mucin production in medullary carcinoma of the thyroid.

Mucin production in medullary carcinoma of the thyroid is rarely mentioned in the literature. We studied 36 cases of medullary carcinoma; 32 lesions were sporadic and four were genetic variants. In 15 cases (42%), mucin production was demonstrated by histochemical means. In six cases (17%), the mucin was only extracellular; in three (8%), it was mostly extracellular, but with foci of intracellular deposits; and in six cases (17%), it was equally extracellular and intracellular. Mucin secretion could be demonstrated in both the primary thyroid tumor and the nodal metastases. No consistent correlation could be demonstrated between the histologic pattern, the staining properties of the tumor cells, and the sporadic or genetic occurrence of the tumor. Mucin was more frequently identified in medullary carcinomas (42%) than in other carcinomas (9.1%) of the thyroid gland. As mucin can be identified in approximately half of the medullary carcinomas, this primary thyroid lesion should be considered a possible source for a cervical node containing mucin positive carcinoma cells.

Adolescent↗

PubMed1980

Comparison of nephelometry and immunofluorescence for immunoglobulin quantitation in pathologic sera.

Nephelometers from Beckman, Hyland and Technicon, and the immunofluorescent system from International Diagnostic Technology were evaluated for IgG, IgM, and IgA quantitation in pathologic sera. Within-run, between-run, and between-day imprecision of each instrument varied for each immunoglobulin and for different levels of the same immunoglobulin. Thus, no instrument showed clearly superior precision. However, for elevated immunoglobulin levels, Technicon had poorer between-day precision than the other instruments (p less than 0.05). Comparison of monoclonal immunoglobulin quantitation with monoclonal protein quantitation by serum protein electrophoresis in 13 patients showed best correlation for the Beckman instrument (r = 0.942). Quantitation of IgG, IgM, and IgA in 50 specimens required approximately 330, 390, 480, and 480 min to complete with Hyland, International Diagnostic Technology, Beckman, and Technicon, respectively. Our evaluation suggests that the proportion of abnormal specimens in the workload and the availability of reagents for desired assays should be considered in determining the suitability of one of these instruments for a particular laboratory.

Dysgammaglobulinemia↗

PubMedDate not supplied

Lebanese population: prevalence of the erythrocyte phenotypes.

STUDY OBJECTIVES: This survey was designed to be a descriptive study of the erythrocyte phenotype prevalence in Lebanon. The general aim was to provide transfusion centers and blood banks with the occurrence of the nation's erythrocyte phenotypes in the population they are serving. The results were descriptively compared to Caucasians. SUBJECTS AND METHODS: 632 blood samples were collected from the Lebanese population in the 5 muhafazats (regions). Of which, 350 samples were extensively phenotyped for the blood group systems ABO, Kell, Kidd, Duffy, MNS, Lewis, Lutheran and P; and 282 samples were selectively phenotyped for Fy(a), Fy(b) and Kp(a). Additionally, 3064 random blood donors were studied for the ABO and D blood groups. MAIN RESULTS: With respect to the blood group phenotypes, the Lebanese are similar to the Caucasian population with the exception of rr, Le(b), Le (a-b-), Fy (a-b-), M+N+S-s+ and M-N-S-s+. CONCLUSION: It is of scientific cognizance and interest that the Lebanese erythrocyte phenotypes closely resemble that of the Caucasians: nevertheless, certain novel differences are present, and possibly, there exists a phenotype that attributes to admixture of the African gene in a Middle Eastern population.

Arabs↗

PubMedDate not supplied

Liesegang-like rings in fine needle aspirates of renal/perirenal hemorrhagic cysts.

Periodic structures with equally spaced radial striations, identified as Liesegang-like rings, were encountered in fine needle aspirates of two patients' hemorrhagic renal/perirenal cysts. The patients, one 60 and the other 39 years old, had acute right-flank pain; both underwent nephrectomy. The ring structures ranged in size from 8 microns to 200 microns in diameter and had regularly striated double walls. Histochemical and immunoperoxidase tests for iron, calcium, mucopolysaccharides, amyloid, keratin and hemoglobin performed on the tissue sections of the resected specimens gave negative results. With electron microscopy, the ring structures of one of the cases displayed a fine fibrillary composition. Since these Liesegang-like structures may be mistaken for parasites or necrotic tissue, pathologists should be aware of them. To our knowledge, this is the first report of Liesegang-like rings in the cytology literature.

Adult↗

PubMedDate not supplied

Amiodarone pulmonary toxicity. Clinical, cytologic and ultrastructural findings.

Amiodarone, a new antiarrhythmic drug, may produce severe and potentially lethal pulmonary toxicity. A case is presented of a patient on amiodarone therapy who presented with recurrent pleural effusions and subsequently developed pulmonary infiltrates. The diagnosis of lung toxicity was documented by the cytologic examination of the pleural effusions and the bronchial washings. It was further supported by the ultrastructural demonstration of the characteristic cytoplasmic osmiophilic lamellar inclusions in the foamy macrophages. We conclude that cytologic and ultrastructural examinations of bronchial lavage cells are extremely helpful in the diagnosis of amiodarone-induced pulmonary toxicity.

Aged↗

PubMedDate not supplied

Cerebrospinal fluid cytology in histiocytic proliferative disorders.

Morphologically atypical histiocytes were observed in the cerebrospinal fluid (CSF) of five patients with histiocytic proliferative disorders, including one each classified as Letterer-Siwe disease and Hand-Schüller-Christian disease and three as malignant histiocytosis. In all of these patients except the one with Letterer-Siwe disease, neurologic examination, CSF leukocyte count and protein and glucose concentrations were normal. Necropsy studies in the three fatal cases (one patient with Letterer-Siwe disease and two with malignant histiocytosis) demonstrated leptomeningeal involvement by atypical histiocytes in all three and brain involvement in the patient with Letterer-Siwe disease. These observations suggest that cytologic examination of CSF is warranted in patients with histiocytic proliferative disorders and may be reliable in documenting central nervous system, particularly leptomeningeal, involvement. The atypicality of the histiocytes in the CSF, however, was not indicative of the classification of the histiocytic proliferative disorder. Because the patient with Hand-Schüller-Christian disease continues to have a normal neurologic examination seven years after abnormal histiocytes were initially detected in his CSF, we believe that the clinical condition of the patient and classification of the histiocytic proliferative disorder are of primary importance for initiating aggressive therapy directed at the central nervous system.

Adolescent↗

PubMedDate not supplied

Cytopathology of pleural endometriosis.

Cytomorphologic features in pleural effusions obtained from two cases of endometriosis of the pleura are described. These young patients presented with recurrent right pneumothorax and hemorrhagic pleural effusions. In the pleural fluid specimens, recognition of endometrial epithelial cells, which generally occur in tissue fragments or singly, and of hemosiderin-laden histiocytic cells, which probably represent endometrial stromal elements, is considered essential to establishing such a diagnosis on a morphologic basis alone. A brief review of the literature is presented.

Adult↗