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W Gorczyca

Publications and source records attributed to W Gorczyca.

At least 19 recordsLinked to original sources
PubMed1992

Cell cycle-related expression of p120 nucleolar antigen in normal human lymphocytes and in cells of HL-60 and MOLT-4 leukemic lines: effects of methotrexate, camptothecin, and teniposide.

Expression of the proliferation-associated nucleolar antigen p120 was studied by flow cytometry in human quiescent and phytohemagglutinin-stimulated lymphocytes, as well as in human lymphocytic (MOLT-4) and promyelocytic (HL-60) cell lines. Bivariate analysis of p120 and DNA content made it possible to correlate p120 expression with cell position in the cycle. Proliferating lymphocytes and MOLT-4 and HL-60 cells had a similar pattern of p120 expression. Populations of G1 cells, in all three cell types, were very heterogenous with respect to p120, and a threshold in G1 was observed. The cells with a p120 level below the threshold value did not enter S phase. An increase in p120 was observed during progression through S phase, and the antigen was maximally expressed in G2 cells. The p120/DNA content ratio, however, was highest in late G1 cells (G1B) and was declining during S and G2. The data thus suggest that p120 may be degraded during mitosis and that the postmitotic cells inherit little, if any, of this protein; the antigen then accumulates predominantly during G1, and must reach a threshold level to enable the cells to enter S phase. Antigen p120 could not be detected in noncycling lymphocytes nor in HL-60 cells induced to myeloid differentiation by growth in the presence of dimethyl sulfoxide. Treatment of MOLT-4 cells with pharmacological concentrations of methotrexate, camptothecin, or teniposide induced cell arrest in S or G2; expression of p120 in the arrested cells was unchanged from that of untreated MOLT-4 controls at the same phase of the cycle. The level of p120 was minimal in MOLT-4 or HL-60 cells arrested in M phase by vinblastine, but vinblastine had no effect on p120 fluorescence of interphase cells. Camptothecin or teniposide induced apoptosis selectively in S phase of HL-60 cells; apoptotic cells from camptothecin-treated cultures, however, despite the marked nucleolysis, still expressed p120. The data on the drug-treated cells indicate that the p120 level in tumors of patients may be used as a marker of tumor/malignancy even in clinical samples obtained during treatment.

Antigens, Neoplasm↗
PubMed1992

Effect of ionic strength in immunocytochemical detection of the proliferation associated nuclear antigens p120, PCNA, and the protein reacting with Ki-67 antibody.

This study was aimed at revealing whether or not ionic interactions between the epitope of the antigen detected by Ki-67 antibody, or the proliferation-associated proteins PCNA or p120, and neighboring cellular constituents impede detectability of these antigens in HL-60 cells by indirect immunofluorescence assay. To this end, the ionic strength (NaCl concentration) of the solutions in which cells were suspended during their fixation with 0.5% paraformaldehyde was increased, to up to 1.65 M NaCl, to weaken the intra- and/or intermolecular ionic interactions during the process of crosslinking, and the cells were then immunostained. Fluorescence of cells reacting with Ki-67 antibody was maximally increased after their treatment with 1.15 M NaCl; the average increase was nearly 110% above the level seen with the standard methodology utilizing 0.15 M NaCl. The increase was greater for cells in the G1 phase of the cell cycle compared to cells in S or G2. Fluorescence of cells stained with the PCNA antibody was maximally enhanced after cell treatment with 0.65 M NaCl. The enhancement, however, varied depending on the source of the antibody; it was nearly 200% in the case of the antibody provided by Boehringer and over 100% by DAKO. Detection of the nucleolar antigen p120 was not significantly affected by 0.65-1.65 M NaCl. The data indicate that ionic interactions between cellular constituents indeed play a role in masking the epitope of PCNA and the antigen detected by Ki-67.(ABSTRACT TRUNCATED AT 250 WORDS)

Cell Cycle↗
PubMed1992

Features of apoptotic cells measured by flow cytometry.

The present review describes several methods to characterize and differentiate between two different mechanisms of cell death, apoptosis and necrosis. Most of these methods were applied to studies of apoptosis triggered in the human leukemic HL-60 cell line by DNA topoisomerase I or II inhibitors, and in rat thymocytes by either topoisomerase inhibitors or prednisolone. In most cases, apoptosis was selective to cells in a particular phase of the cell cycle: only S-phase HL-60 cells and G0 thymocytes were mainly affected. Necrosis was induced by excessively high concentrations of these drugs. The following cell features were found useful to characterize the mode of cell death: a) Activation of an endonuclease in apoptocic cells resulted in extraction of the low molecular weight DNA following cell permeabilization, which, in turn, led to their decreased stainability with DNA-specific fluorochromes. Measurements of DNA content made it possible to identify apoptotic cells and to recognize the cell cycle phase specificity of the apoptotic process. b) Plasma membrane integrity, which is lost in necrotic but not apoptotic cells, was probed by the exclusion of propidium iodide (PI). The combination of PI followed by Hoechst 33342 proved to be an excellent probe to distinguish live, necrotic, early- and late-apoptotic cells. c) Mitochondrial transmembrane potential, assayed by retention of rhodamine 123 was preserved in apoptotic but not necrotic cells. d) The ATP-dependent lysosomal proton pump, tested by the supravital uptake of acridine orange (AO) was also preserved in apoptotic but not necrotic cells. e) Bivariate analysis of cells stained for DNA and protein revealed markedly diminished protein content in apoptotic cells, most likely due to activation of endogenous proteases. Necrotic cells, having leaky membranes, had minimal protein content. f) Staining of RNA allowed for the discrimination of G0 from G1 cells and thus made it possible to reveal that apoptosis was selective to G0 thymocytes. g) The decrease in forward light scatter, paralleled either by no change (HL-60 cells) or an increase (thymocytes) of right angle scatter, were early changes during apoptosis. h) The sensitivity of DNA in situ to denaturation, was increased in apoptotic and necrotic cells. This feature, probed by staining with AO at low pH, provided a sensitive and early assay to discriminate between live, apoptotic and necrotic cells, and to evaluate the cell cycle phase specificity of these processes. i) The in situ nick translation assay employing labeled triphosphonucleotides can be used to reveal DNA strand breaks, to detect the very early stages of apoptosis.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1992

Aspiration cytology in the diagnosis of malignant tumors in children.

On the basis of 65 fine-needle aspiration biopsies (FNAB) the efficiency of aspiration cytology combined with immunocytochemistry in preoperative diagnosis of malignant tumors in children was evaluated. All FNAB were performed under ultrasound or fluoroscopy guidance. There were no false-positive diagnoses. Morphological type of the tumor was properly diagnosed preoperatively in 50 patients. In 10 aspirates, the tumor type could not be diagnosed on the basis of light microscopy and immunocytochemistry. Due to technical reasons, five false-negative diagnoses (7.7%) were made. This study showed that FNAB is a safe, rapid, and effective method, which enables preoperative diagnosis of children's tumors in most cases.

Adolescent↗
PubMed1992

Aspiration biopsy of the breast tumors. Analysis of diagnostically difficult cases.

In this paper the authors described those of the breast fine needle aspirates which were difficult for interpretation e.g. clear-cut differentiation between benign and malignant character of the lesion could not be made. There were 40 such cases (1.96%) out of 2332 breast tumors biopsied between 1987-1989. In the cases that proved to be malignant on histology the authors described cytological features which speak in favour of malignancy. In the group of smears which proved to be benign on histology the authors described the features that imitate atypia and should not be misdiagnosed as malignant. The described criteria may be of some help in cytological diagnosis of breast masses.

Adenofibroma↗
PubMed1992

Binding properties and expression of the Fc gamma receptors on guinea pig peritoneal macrophages treated with inhibitors of glycosylation.

The effect of inhibition of glycosylation in guinea pig peritoneal macrophages on interaction of their surface Fc gamma receptors with guinea pig and rabbit IgG was studied. The inhibitors used were tunicamycin and monensin. The cells treated with tunicamycin incorporated markedly less [3H]mannose, bound less peanut (PNA) and wheat germ (WGA) lectins and showed diminished ability of binding IgG in comparison with control cells. Treatment of the cells with monensin resulted in an increased incorporation of [3H]mannose, increased binding of PNA but a decreased binding of WGA. Monensin affected binding of guinea pig IgG2 and rabbit IgG to macrophages and had no effect on guinea pig IgG1 binding. Analysis of binding parameters showed that although the number of IgG-binding sites on treated cells was significantly lower, especially in the case of tunicamycin, the apparent association constants were 2-4 times higher than in control cells. The effect of tunicamycin and monensin on parameters of binding of guinea pig IgG2 or rabbit immunoglobulins was much more pronounced than in the case of binding guinea pig IgG1. The results showed that glycosylation modulates expression and IgG binding ability of the Fc gamma receptors on the surface of guinea pig peritoneal macrophages.

Animals↗
PubMed1991

Effect of glycosylation inhibitors on binding properties of the Fc gamma receptors from guinea pig peritoneal macrophages.

Guinea pig peritoneal macrophages possess on their surfaces receptors for the Fc region of IgG immunoglobulins (Fc gamma R). The cells treated with the glycosylation inhibitors tunicamycin or monensin interacted with IgG with a higher affinity and showed a lower number of IgG-binding sites in comparison with control cells. This indicates that the interaction of IgG with the macrophage Fc gamma receptor depends on the degree of glycosylation of the cell surface glycoconjugates and that glycosylation of the macrophage Fc gamma receptor is important for the expression of the mature form of the receptor.

Animals↗
PubMed1991

Storiform neurofibroma (Bednar tumor). A case report.

Clinical data and morphological features of the storiform neurofibroma, presenting as an exophytic tumor of the trunk in 30 years old white man are described. This benign tumor, is microscopically similar to dermatofibrosarcoma protuberans and differs from the letter by the presence of melanin containing cells.

Adult↗
PubMed1990

[Immunocytochemical evaluation of estrogen receptors in histological specimens of primary breast cancer].

Immunocytochemical methods (ER-ICA) by using monoclonal antibodies were applied to determine the presence of estrogen receptors (ER) in 44 primary breast cancers in women. Of this 48% of the tumours were classified as receptor positive. In these tumours the nuclei had a clearly positive heterogenous colouration. In three cases a positive reaction was also found in benign epithelial cells of the breast. ER determinations by ER-ICA method were compared with quantitative analysis carried out by using radioligand and immunoenzymatic methods. There was a strong correlation between immunocytochemical ER evaluations and quantitative methods. We also found a correlation of the menopause state and patients age and ER content.

Adult↗
PubMed1990

Shedding of the guinea pig peritoneal macrophage Fc gamma receptor. Effect on apparent association constant and on the number of IgG-binding sites on the cells.

During our studies on the structure and properties of guinea pig peritoneal macrophage Fc gamma receptor we observed that these cells spontaneously release an IgG-binding material into supernatant. Although the shedding was accompanied by a decrease in IgG-binding ability of macrophages, the number of IgG-binding sites/cell before and after shedding was similar. However, macrophages after the shedding interacted with IgG with a lower apparent association constant, Ka. Therefore, we assume that the decrease of IgG-binding ability of cells was an effect of decrease in value of Ka. Experiments with protein synthesis inhibitors showed that the shed receptor is replaced by "de novo" synthesized receptor molecules.

Animals↗
PubMed1989

Cell surface sialic acid affects immunoglobulin binding to macrophages.

We demonstrate that guinea pig peritoneal macrophages pretreated with neuraminidase from Vibrio cholerae bind more 125I-IgG than non-treated cells. Estimation of binding constants (Ka and Bmax) shows that the elevation of binding is the result of an increase in affinity and not in the number of receptors for IgG. The change of affinity is proportional to amounts of sialic acid liberated from the cells by increasing doses of neuraminidase. It is also shown that affinity of interactions of IgG with the macrophage receptor is pH dependent. These results indicate that electrostatic forces are important for IgG binding to the macrophage Fc gamma R. The IgG-Fc gamma R interaction can be modulated by changing the degree of sialylation of the macrophage surface glycoconjugates.

Animals↗
PubMed1989

Expression of ras oncogene p21 protein in early gastric carcinoma and adjacent gastric epithelia.

The expression of the ras gene product p21 in normal gastric mucosa, early gastric carcinoma of diffuse (gastric) and intestinal types, and in adjacent mucosal abnormalities is reported. The analysis was performed on paraffin sections by an immunohistochemical assay using the mouse monoclonal antibody RAP-5 and the rat monoclonal antibody Y13-259. Expression of ras p21 was assessed by staining intensity and percentage of positively stained cells. In comparison to normal gastric mucosa of non-cancer patients, p21 was overexpressed in nearly all early carcinomas of both types and in the dysplastic and/or metaplastic mucosal alterations accompanying intestinal type of gastric cancer. Increased p21 expression was also observed in the normal-appearing mucosa adjacent to early carcinomas of diffuse type, but not in the morphologically normal gastric epithelium adjacent to the intestinal type. The results of this investigation suggest that ras p21 overexpression may be related to early events of human gastric carcinogenesis. The study supports the notion of different pathways in the development of diffuse (gastric) and intestinal types of gastric carcinomas.

Adenocarcinoma↗
PubMed1989

Expression of ras oncogene p21 protein in relation to regional spread of human breast carcinomas.

The oncogenes most frequently detected in human tumors belong to the ras gene family (Ha-ras, Ki-ras, and N-ras). These genes encode a group of closely related 21,000 dalton proteins termed p21. An immunohistochemical study of ras p21 expression was carried out on paraffin sections of 54 human breast carcinomas using monoclonal antibodies to p21. The control group consisted of ten cases of benign fibrocystic disease. The p21 expression was significantly higher in cancer cells than in epithelial cells of control specimens. No correlations, however, were observed between oncogene product expression and tumor size, histologic type, or grade. As a group, tumors with axillary lymph node metastases expressed higher levels of ras p21 than nonmetastasizing tumors. However, because of the significant overlap in individual p21 values, it is unlikely that the immunohistochemical assay for p21 could be used to predict the behavior of mammary carcinomas.

Breast Neoplasms↗
PubMed1989

Wheat germ agglutinin binding sites on human urothelial cells of different grades of transformation.

125I-Wheat germ agglutinin (WGA) binding parameters of human urothelial cell lines of different grades of transformation (TGrII and TGrIII) were compared. The values of association constant (Ka) and the number of binding sites/cell for HCV29 (TGrII) cell line were about 3 x 10(6) M-1 and over 4 x 10(7), respectively. Two TGrIII cell lines, HCV29T and Hu549 revealed lower values for Ka, and considerably higher numbers of binding sites/cell (about 3 x 10(8) and 2 x 10(8), respectively). Binding of 125I-WGA to total cellular proteins resolved by SDS-PAGE and transferred to nitrocellulose showed multiple diffused bands in the range of 58-180 kDa. Some of these bands were characteristic for TGrII cells (124 kDa) or TGrIII cells (135 and 148 kDa).

Animals↗
PubMed1988

Microadenomas of the human pituitary and their vascularization.

During 100 autopsies of patients who had no previous endocrinological problem, selective injections of the pituitary arterial systems were performed. Pituitary glands were examined from 60 male and 40 female patients with an average age of 68 years. Detailed histological and immunocytological studies using peroxidase-antiperoxidase techniques for prolactin (PRL), adrenocorticocotropic hormone (ACTH), follicle-stimulating hormone, thyroid-stimulating hormone, and growth hormone were used. Thirty-three microadenomas were found in 27 patients; 22 were single, 4 were double, and 1 was triple. Fourteen were nonreactive to immunostaining, 10 were reactive to PRL, and 9 were reactive to ACTH. Their diameters ranged between 0.5 and 5.0 mm, and they were located mainly in the lateral wings and the peripheral zone of the anterior pituitary gland. Microvascular study revealed that 22 microadenomas (66%) had direct extraportal arterial supplies. Because the hypothalamic factors are transported to the anterior lobe through the portal vessels, this study suggests that the formation of microadenomas occurs most frequently outside the hypothalamic-hypophyseal portal system and further supports the hypothesis that pituitary adenomas may arise de novo without the influence of hypothalamic factors.

Adenoma↗
PubMed1987

Microvascular anatomy of Heubner's recurrent artery.

The microvascular anatomy of Heubner's recurrent artery (RAH) was studied in 50 human brains (100 hemispheres) using acrylic paint under the operative microscope. The recurrent artery of Heubner was always found as a single vessel in 28 cases (28%) and multiple vessels in 72% (double vessels in 48%, triple in 23% and quadruple in 1%). Altogether 197 RAH were found in 100 hemispheres, averaging 1.97 arteries per hemisphere. In 44 instances, it originated from the proximal part of the A1-segment of the anterior cerebral artery. The diameters of the RAH ranged from 0.4 to 1.5 mm. Their vascular territory was variable. Four groups of distributing branches were found in the RAH: frontal and hypothalamic, olfactory, perforating and sylvian-fissure branches. In 12 hemispheres, anastomoses were found between the perforating branches of the RAH and the middle cerebral artery. In five cases (5%) anastomoses were present between the perforating branches of the MCA and the olfactory branch of the RAH. In one case (1%), an anastomosis was found between two RAH.

Cerebral Arteries↗
PubMed1987

Anatomy of diaphragmatic circulation.

The diaphragmatic circulation was studied in 48 mongrel dogs weighing 10-35 kg by injecting acrylic coloring into the arteries and veins of the diaphragm. The phrenic arteries and internal mammary arteries were found to anastomose head to head, forming an internal arterial circle around the medial leaflet of the diaphragm tendon. This arterial circle emitted vascular branches that traveled between muscle fibers toward the periphery of the diaphragm. These branches anastomosed with vessels of the intercostal arteries to form costophrenic arcades all along the fibers of the crural and costal diaphragms. The intercostal arteries were anastomosed to one another by small vessels within the muscular diaphragm, thus forming an arterial ring around the insertions of the diaphragm on the ribs. The venous drainage has an anatomic distribution similar to that observed on the arterial side, but with the additional presence of valves that could play a role in directing blood flow.

Animals↗