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Biomedical subjects

G Kasnic

Publications and source records attributed to G Kasnic.

14 recordsLinked to original sources
PubMed1994

The synovial structure of breast-implant-associated bursae.

Over 2 million silicone breast prostheses have been implanted since they were introduced in the 1960s. After implantation, a fibrovascular tissue reaction referred to as a "capsule" is observed. Many consider this capsule to be a static structure, an effective barrier to the egress of foreign material. However, reports documenting the presence of silicone within lymph nodes of patients with apparently unruptured implants indicate that silicone may be transported away from the breast-implant capsule. To characterize the cells making up the breast-implant capsule, 183 capsules from 103 ruptured or bleeding implants and 80 intact implants were studied. Gross and light microscopic studies were performed on all, and selected capsules were subjected to ultrastructural study and Fourier-transform infrared spectroscopy. Light microscopic examination of the capsule revealed an organized, layered structure with an associated network of endothelia-lined spaces. The capsules varied in cellularity, depending on the type and integrity of the implant. The superficial cell layer of all capsules had cytoplasmic processes directed toward the surface. These long cytoplasmic processes contained vacuoles ultrastructurally, indicating phagocytic and pinocytotic capability. These cells bore immunological markers of bone marrow derived macrophage-type cells. The extracellular matrix of the surface layer consisted of an amorphous fibrillar protein lacking the ultrastructural periodicity of mature collagen. No cell-to-cell junctions were observed. Deeper capsular layers were characterized by fibroblast-type cells in a collagen matrix. No capsules studied contained basement membrane or basal lamina between the stroma of the capsule and the surface cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Breast Diseases↗
PubMed1993

Induction of a polarized micro-environment by human T cells and interferon-gamma in three-dimensional spheroid cultures of human endometrial epithelial cells.

Expression of human leukocyte antigen (HLA)-DR molecules and proliferation of epithelium in human endometrium are polarized. We have suggested that the induction of such a polarized micro-environment is T cell and interferon (IFN)-gamma dependent. The present study was designed to demonstrate the induction of such a micro-environment around T cells and around the source of IFN-gamma. Spheroids reminiscent of endometrial glands were formed by allowing three-dimensional aggregation of endometrial epithelial cells of a cloned HLA-DR negative endometrial carcinoma cell line (ECC1) over agarose. Both HLA-DR expression and inhibition of proliferation were found to be directly dependent on the dose of IFN-gamma that was allowed to diffuse in the agarose beneath the spheroids. To show that the interaction of the epithelial cells with activated T cells also induces HLA-DR molecules in a paracrine fashion in the epithelial cells, ECC1 spheroids were co-cultured with increasing numbers of allogeneic peripheral blood T cells for various time-intervals. T cells bound to the ECC1 cells, and became activated as indicated by the expression of interleukin (IL)-2 receptor and HLA-DR molecules. A focal HLA-DR expression became apparent in the ECC1 cells adjacent to the T cells. As the number of T cells added to spheroid cultures was increased, a concomitant increase in the number of HLA-DR positive ECC1 cells occurred and HLA-DR immunoreactivity was enhanced in each cell. There was a corresponding decrease in the proliferation of the ECC1 cells in T cell-ECC1 spheroid co-cultures. Based on these data, we suggest that activation of T cells is associated with the induction of HLA-DR expression and inhibition of proliferation in a paracrine fashion in the epithelial cells and may be responsible for the creation of a polarized micro-environment in vivo.

Animals↗
PubMed1992

The significance of an elevated serum lysozyme value in acute myelogenous leukemia with eosinophilia.

According to criteria established by the French-American-British (FAB) classification, a diagnosis of acute myelomonoblastic leukemia (FAB M4) is based on the presence of 20% bone marrow monocytes or a serum lysozyme level that exceeds the reference value by three times. Reported here is a case of acute myelogenous leukemia with eosinophilia and a cytogenetic inversion of chromosome 16 (inv 16) that lacks morphologic, cytochemical, and immunophenotypic features of monocytic differentiation, but which is associated with an elevated serum lysozyme value. The authors used an immunoelectron microscope to localize lysozyme to both normal and abnormal eosinophil granules, in addition to the secondary granules of myeloid precursors and monocytes. This enzyme could not be demonstrated within the myeloblasts of the patient studied. Postfixation with osmium tetroxide greatly reduced the staining intensity within the crystalloids of normal eosinophils, but only minimally affected that of monocytes, neutrophils, normal eosinophil granule matrix, and the abnormal granules of the leukemic eosinophils. These results demonstrate that lysozyme is present in both normal and leukemic eosinophils and that elevation of serum lysozyme in patients with acute myelogenous leukemia with eosinophilia is not a reliable indicator of monocytic differentiation. Furthermore, an occasional case of acute leukemia with inv 16 is classifiable as acute myelogenous leukemia with differentiation (FAB M2).

Adult↗
PubMed1982

Endothelial and platelet reactions in the idiopathic nephrotic syndrome: an ultrastructural study.

In this ultrastructural study we have critically examined blood vascular reactions in the glomerular microcirculation of 14 patients with idiopathic membranous nephropathy and 11 patients with minimal change disease. In all patients, bullous intracellular edema was observed in the glomerular endothelium, a change interpreted as reflecting endothelial injury. Platelets in various stages of degranulation were seen in relation to the endothelium. In ten biopsy specimens platelet aggregates were observed. Platelets with exhausted secretory products ("ghosts") were frequently identified in areas contiguous with other obvious degranulating platelets. In some cases, pseudopodia of degranulating platelets were observed in direct contact with the glomerular basement membrane in areas denuded of endothelium. Tactoids of fibrin were seen in nine cases in relation to degranulating platelets or edematous endothelium, or both. Our data suggest that these endothelial and platelet reactions play a role in the pathophysiology oi the nephrotic syndrome in patients with minimal change disease or idiopathic membranous nephropathy.

Adult↗
PubMed1975

Studies on the intracisternal A-type particles in mouse plasma cell tumors: induction of maturation of the particles.

Maturation of the intracisternal A-type particle found in two mouse plasma cell tumors was induced by treating the cells in culture with IDU-DMSO or with DMSO only. Morphologically, the mature particles with electron-dense nucleoids closely resembled the mature particles described in human tumor cell lines treated in a like manner. They also closely resembled the virus that has been described in guinea pig leukemias. It was not possible to demonstrate infectivity of the mature particle, as latent intracisternal A-type particles induced by IDU were found in the mouse cells presumed to be free of virus. The biochemical studies did not show distinct new peaks of virus-specific particles in sucrose density gradients when the particles in the treated cells were compared with the particles of the untreated cells. There was a difference in the density of the particles observed in the induced cells (1.2) and those of the control cells (1.185). This may reflect the difficulty of separating mature and immature particles. Analysis of the RNA present in the particles showed that the ratio of heavy-molecular-weight RNA in activated cells to the predominant species (21S) is much greater than that in control cells. Detectable levels of enzyme activity were not found in the induced particles. This could be due to too low a concentration of particles in the preparations.

Animals↗
PubMed1972

Oyster herpes-type virus.

A herpes-type virus infection, the first to be found in an invertebrate animal, is reported in the oyster Crassostrea virginica. Intranuclear herpes-type viral inclusions were more prevalent in the oyster at elevated water temperatures of 28 degrees to 30 degrees C than at normal ambient temperatures of 18 degrees to 20 degrees C. The inclusions were associated with a lethal disease at the elevated temperatures.

Animals↗
PubMed1972

Activation of viruses in human tumors by 5-iododeoxyuridine and dimethyl sulfoxide.

Dimethyl sulfoxide added to cultures first treated with 5-iododeoxyuridine increased C-type virus production approximately tenfold in a human rhabdomyosarcoma cell line. 5-Iododeoxyuridine followed by dimethyl sulfoxide also activated a similar C-type virus in a metastatic tumor from a bronchial node taken from a 52-year-old male.

Adenocarcinoma↗
PubMedDate not supplied

Ultrastructure of human platelets processed for transfusion under standard blood bank conditions.

Platelets processed for transfusion are routinely subjected to centrifugation, mechanical agitation and storage at either room temperature or 4 C. To evaluate morphologic changes associated with standard blood bank conditions, platelet units were grouped into four categories: linear agitation at room temperature, agitation at a 90 degrees arc with a Hemolater at room temperature, agitation at a 360 degrees arc with a commercial platelet agitator, and refirgeration at 4 C without agitation. Cold (4 C) preservation resulted in a surprisingly good preservation of platelet ultrastructure, even at 72 hours of storage. By contrast, harsh linear agitation at room temperature brought about marked alterations in platelet ultrastructure beginning at 24 hours. The Hemolator agitator with 90 degrees arc was associated with good preservation of platelet organelles even at 72 hours, whereas marked degenerative changes were observed at this time in platelets processed with a commercial agitator with a 360 degrees arc. These results indicate that platelets stored at 4 C or processed at room temperature with an agitator with 90 degrees arc show the best preservation of ultrastructure.

Blood Banks↗
PubMedDate not supplied

Dual differentiation in small cell carcinoma (oat cell carcinoma) of the lung.

Two cases of small cell "undifferentiated" carcinoma (oat cell carcinoma) of the lung with dual neurosecretory and squamous differentiation are reported. One was treated with various regimens of chemotherapy and radiotherapy; the other was untreated at the time of biopsy. By electron microscopy, the same tumor cells showed membrane-bound, dense-core, neurosecretory-type granules and bundles of tonofibrils denoting squamous differentiation. This dual differentiation underlies the difficulty of ascribing an exclusively neural histogenesis to small cell carcinomas with neurosecretory-type granules. It is possible that entoderm-associated neuroectodermal tumors develop features of autochthonous entodermal tumors as a result of microenvironmental influences. An alternative hypothesis would be that small cell tumors are derived from basal reserve bronchoepithelial cells with pluripotentialities.

Aged↗
PubMedDate not supplied

Nuclear and cytoplasmic inclusions in disseminated human cytomegalovirus infection.

A case of disseminated human cytomegalovirus infection is described in a full-term female who expired 3 1/2 h after birth. Cytomegalic inclusions, both intranuclear and intracytoplasmic, were observed mainly in the kidneys, liver, lungs, and anterior pituitary but were not seen in the bone marrow and spleen. Whereas the nuclear inclusions consisted of an amorphous filamentous meshwork with a variable number of pleomorphic capsids, the cytoplasmic inclusions were composed of membrane-bound aggregates of mature virions with dense cores and multilayered envelopes. The complex envelopment process of cytomegalovirus appears to involve successive coats derived from the nuclear membrane and from the endoplasmic reticulum or cytoplasmic vesicles.

Bronchi↗
PubMedDate not supplied

Soft tissue sarcoma with complex membranous and microtubular inclusions.

Cytoplasmic inclusions of great complexity are encountered in an undifferentiated sarcoma of a 67-year-old woman. The tumor arising in adipose tissue between muscles of the parspinous musculature contains inclusions in most tumor cells represented by four different morphologic types. Two are intracisternal, designated microtubular reticular structure (TRS) and tubular confronting cisternae (TCC). Two others are cytoplasmic and consist of crystalline microtubular arrays and of confronting cisternal complexes of smooth endoplasmic reticulum (SER). This latter is uniquely complex and not found in previous descriptions. Tumors of mesenchymal origin and experimental virus-induced tumors are known to contain short segments of confronting cisternae and TRS. Tubuloreticular structures and TCC are well documented in cases of lupus, in human immunodeficiency virus infections, in T-cell leukemia, and in experimental viral hepatitis in chimpanzees. The patient presented has none of the coincidental pathologic condition associated with occurrence of TRS and TCC. The morphology of the inclusions and their relationships are illustrated although their biological significance remains obscure.

Adipose Tissue↗