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Biomedical subjects

J Jaroszewski

Publications and source records attributed to J Jaroszewski.

17 recordsLinked to original sources
PubMed1992

Three-dimensional reconstruction and stereometric analysis of Langerhans cells in mouse epidermis.

In the presented studies stereometric analysis and spatial reconstruction was performed on two Langerhans cell (LC) types. One was free of LC-I and the other contained LC-II Birbeck granules in the perinuclear space. The presented stereometric analysis demonstrated significant differences between the so-distinguished two cell types. Differences were observed not only in the number and distribution of Birbeck's granules but also in the areas of smooth and rough endoplasmic reticulum, in the area of vesicles surrounding Golgi apparatus, in the volume of cisterns of the apparatus, and in the ratio of cell nucleus area to its volume. Differences noted between the two cell types were of quantitative character. They might result from different stages of differentiation of the cells from their precursors in the epidermis or from distinct functional stages of the cells.

Animals↗
PubMed1992

Analysis of spatial structure of thymocytes and of their contacts with thymic non-lymphoid cells.

The study aimed et determining morphological relations between thymic cells and thymocytes. The studies were performed on 16 days old rats of Wistar strain. The material was processed for ultrastructural studies in a routine manner. For 50 thymocytes computer reconstruction was performed which allowed to define cell volume, volume of cell nucleus and of condensed chromatin. The value characterizing three-dimensional morphology of thymocytes provided grounds for analysis using graph theory. The stereological methods allowed to examine microarchitecture of individual thymic zones. Thymocytes in contact with dendritic cells or with macrophages were found to differ in morphology from thymocytes with no such contacts. The results indicated direct effect of dendritic cells and of macrophages on thymocytes.

Animals↗
PubMed1992

Analysis of thymocytes contacts with other thymic cells.

The study aimed et defining morphological relationships between thymic stroma cells and thymocytes. The studies were conducted on 16-days old Wistar strain rats. The material was routinely processed for ultrastructural examination. On grounds of serial section analysis, types of contacts of 83 thymocytes were established, for each cell total area and areas of contact with other cells were estimated. Employing stereological techniques microarchitecture of individual thymic zones was studied. The results point to a direct influence of thymic stroma cells on thymocytes.

Animals↗
PubMed1990

The coccygeal artery as a route for the administration of drugs into the reproductive tract of cattle.

A simple procedure is described for cannulating the aorta abdominalis of cattle through the coccygeal artery, and for positioning the tip of the cannula close to the origin of the ovarian artery. When noradrenaline was infused through the cannula there was a rapid increase in the concentration of progesterone in the peripheral blood, whereas the intravenous infusion of the same dose of noradrenaline had little effect. The procedure can be used for endocrinological studies of the reproductive organs and avoids the more costly and potentially damaging procedure of implanting cannulae during a laparotomy.

Animals↗
PubMed1989

The effect of stress induced experimental gastric ulcers on enterochromaffin cells and on serotonin and 5-hydroxyindolacetic acid levels in stomach and duodenum of the white rat.

In rats subjected to acute or protracted stress of immobilization, gastric and duodenal mucosae were monitored for presence of ulcers and their enterochromaffin cells were examined, identifying them with the use of anti-serotonin antibodies and PAP technique. In parallel, serotonin and 5-hydroxyindolacetic acid levels in the stomach and duodenum were estimated. Ulcers developed only in the stomach and exclusively in stress-unadapted animals. Development of ulcers was paralleled by enterochromaffin cell degranulation, decrease in serotonin levels, and increase in 5-hydroxyindolacetic levels in both the stomach and the duodenum. Significance of the findings for contemporary hypothesis of gastric ulcers' pathogenesis was discussed.

Animals↗
PubMed1978

Cytotoxicity of human peripheral lymphocytes in cell-mediated lympholysis; antibody-dependent cell-mediated lympholysis and natural cytotoxicity assays after mixed lymphocyte culture.

Lymphocytes that have been purified by Ficoll-Hypaque centrifugation lose antibody-dependent and natural cytotoxic activities upon culture in tissue culture medium supplemented with human plasma. However, stimulation of peripheral lymphocytes in the mixed leukocyte culture (MLC) appears to enhance killer (K) and natural killer (NK) activities in addition to generating cytotoxic T ymphocytes. Enhancement of NK and antibody dependent activities appears to correlate with cell division as measured by 3H-thymidine uptake. However, elimination of dividing cells in the MLC by addition of 5-bromodeoxyuridine has no effect on NK and K cells activities. Since this treatment abolishes cell-mediated lympholysis mediated by cytotoxic T lymphocytes, it is a useful probe for determining the relative activities of NK, K, and cytotoxic T lymphocyte effector cells after lymphocyte stimulation.

Antibody-Dependent Cell Cytotoxicity↗
PubMed1978

Proliferation of human lymphocytes by mitogen stimulated cells.

Lymphocytes cultured for three days with PHA or Con A were capable of inducing vigorous proliferation of autologous or allogeneic lymphocytes. Kinetics of the response varied with mitogen dose used for obtaining stimulating cells and with the ratio of stimulating to responder cells. A requirement for viable, mitogen-reactive lymphocytes cultured for at least two days with the mitogen, for their contact with the reacting cells and an absence of significant quantities of mitogen on Con A lymphoblasts examined by electron microscopy demonstrated that a mitogen itself was not responsible for the stimulation. The PHA blast-stimulated lymphocytes were not cytotoxic to PHA blasts nor did they diminish lymphocyte stimulating abilities of PHA blasts in vitro cultures. This indicated that PHA did not induce proliferation of autologous lymphocytes by derivatization of lymphocyte surface.

Cell Cycle↗
PubMed1976

Blast transformation induced by spermatozoa.

Human lymphocytes cultured for 3-8 days in the presence of autologous or allogenic spermatozoa undergo blast transformation. Possible mechanisms of the response are discussed.

Animals↗
PubMedDate not supplied

Involvement of beta-adrenoceptors in the regulation of luteal function in cattle.

The infusion of beta-adrenomimetic drug (bamethan sulphate--BS) on day 11 of the oestrous cycle markedly increased peripheral progesterone concentration whereas infusion of beta-antagonist (propranolol) decreased plasma progesterone levels in heifers. Oxytocin injected on days 2-6 of the oestrous cycle shortened the length of the cycle (to 7-9 days) whereas the length of the cycle in heifers injected with oxytocin followed by injections of either BS or xanthinol (theophylline nicotinate--a potent vasodilatory drug) was normal (21.8 +/- 1.7). Heifers injected with BS on days 13-21 of the oestrous cycle had increased levels of progesterone on days 13-19 of the cycle and the length of the cycle was normal (22.3 +/- 0.6 compared with 21.3 +/- 1.5 for the control). The data indicate that: (1) beta-adrenergic stimulation overcomes the action of oxytocin given on days 2-6 of the cycle, whereas the stimulation of beta-receptors on days 13-21 of the oestrous cycle raised progesterone plasma concentration but did not prevent spontaneous luteolysis. (2) Basal secretion of progesterone in cattle is partly dependent on constant beta-adrenergic stimulation.

Animals↗