The lack of classical HLA molecules on trophoblast prevents allorecognition by maternal T lymphocytes, but poses the problem of susceptibility to NK lysis. Expression of the nonclassical class I molecule, HLA-G, on cytotrophoblast may provide the protective effect. However, the class I-negative syncytiotrophoblast escapes NK lysis by maternal PBL.
View Article and Find Full Text PDFA novel human gene RED, and the murine homologue, MuRED, were cloned. These genes were named after the extensive stretch of alternating arginine (R) and glutamic acid (E) or aspartic acid (D) residues that they contain. We term this the 'RED' repeat.
View Article and Find Full Text PDFActa Vet Hung
May 1999
The present study was designed to investigate the effect of a one-month feeding of retinyl acetate (RA) on the retinol (ROL), retinyl palmitate (RP) and beta-carotene (BC) levels in the blood, testicles and ovarian follicles of adult Japanese quails. The basal diet (containing vitamin A at 10 x 10(3) IU/kg) was supplemented with 100 x, 500 x and 1000 x 10(3) IU/kg RA in Groups I, II and III in both sexes. Plasma vitamin A levels rose in all groups.
View Article and Find Full Text PDFLymphocyte adhesion to endothelial cells and the extravascular deposition of fibrin are 2 important processes during pathologic situations such as allograft rejection. Tissue factor (TF) expression was therefore measured on human umbilical vein endothelial cells (HUVECs) after coculture with allogeneic lymphocytes (PBLs) by a factor Xa generation assay. When cocultured with PBLs, HUVECs expressed strong procoagulant activity related to the TF/factor VII-dependent pathway, which was enhanced when endothelial cells were treated with interferon-gamma (IFN-gamma).
View Article and Find Full Text PDFThromb Haemost
November 1998
Extravascular fibrin deposition is frequently observed within and around neoplastic tissue and has been implicated in various aspects of tumor growth. The distribution of fibrin deposits was investigated in squamous cell carcinomas representing different stages of tumor progression of the larynx (n = 25) and hypopharynx (n = 9) by immunofluorescent techniques. Double and treble labelings were used to detect fibrinogen and fibrin in combination with marker antigens for tumor cells (cytokeratin), endothelial cells (von Willebrand factor), macrophages (recognized by KiM7), as well as factor XIII subunit A (FXIIIA) and tenascin (an embryonic extracellular matrix protein newly expressed during tumorigenesis).
View Article and Find Full Text PDFThe aim of this work was to study the effects of benzalkonium chloride (BAC) treatment on the small intestine and its functioning in rats surgically prepared with Thiry-Vella intestinal loop. The loops were treated with either BAC, which ablated much of the myenteric plexus and extrinsic innervation, or with physiological saline (SAL). In vivo drinking experiments were performed to examine the effect on fluid intake and behavioral indices of distending the loop with a balloon.
View Article and Find Full Text PDFRecent findings have led to changes in the traditional concept of nerve recovery, including the realization that injured nerves, like any other injured tissue, need the assistance of blood-derived cells and factors in order to heal. We show that factor XIIIa (FXIIIa, the potentially active a2subunit of factor XIII), an enzyme that participates in blood coagulation by stabilizing the fibrin clot, is also active in the nervous system where it may play a key role in the healing of injured tissue. We demonstrate that the plasma, macrophages and nerves of fish contain a 55 kDa form of transglutaminase that cross-reacts immunologically with the a-subunit of FXIII in mammals (80 kDa).
View Article and Find Full Text PDFBesides flow cytometry, fluorescence microscopy combined with computerized image analysis offers an alternative tool for assessing phagocyte oxidant generation at the single-cell level. This technique provides an opportunity for the direct visualization of cells and simultaneous measurement of cellular fluorescence intensity. Thus, we developed a simple method for the quantitative evaluation of intracellular superoxide anion and hydrogen peroxide production with image cytometry by using hydroethidine and dihydrorhodamine 123 dyes, respectively.
View Article and Find Full Text PDFBackground: The increasing use of progressive noninvasive diagnostic imaging techniques, has substantially increased the detection of incidentally detected renal cell carcinoma (RCC).
Objectives: To determine the manner of presentation of RCC and the frequency of incidentally detected RCC. The natural history of RCC of incidentally discovered RCC was compared with that of symptomatic RCC, the reasons for examination and the methods of diagnosis in patients with incidental tumours were analysed.
To investigate the mechanisms of cellular rejection in pig-to-human xenotransplantation, the proliferation of different human purified lymphocyte subpopulations in response to swine leukocyte Ag class II-negative porcine aortic endothelial cells (PAEC) was measured in the presence or absence of human autologous adherent cells (huAPC). CD8+ lymphocytes proliferated moderately in the absence of huAPC, and the immune response was slightly increased when huAPC were added. CD56+ lymphocytes failed to proliferate in response to PAEC whether huAPC were present or not.
View Article and Find Full Text PDFCombined androgen blockade using surgical or medical (luteinizing hormone-releasing hormone agonist) castration in association with anti-androgen has become the primary therapy in patients with metastatic prostate cancer. Patients undergoing combined androgen blockade will progress within 18-30 months after initial hormonal therapy. When progression occurs following combined androgen blockade, the non-steroid anti-androgen should be subsequently withdrawn.
View Article and Find Full Text PDFExpression of the adenomatous polyposis coli (APC) gene derived exon BS (e.g., brain-specific exon) has been analyzed by RT-PCR.
View Article and Find Full Text PDFEffects of volumetric distension of the small and the large intestine on rats' behavior were compared. Rats were stimulated by a rubber balloon inserted into chronic isolated intestinal loops prepared from the lower duodenum-upper jejunum and from the upper colon in the same animal. Thresholds of 3 reaction classes (weak, strong, and painful) were not different from each other in the 2 loops.
View Article and Find Full Text PDFObjective: The aim of this study is to evaluate the short and mid-term efficacy of the Transmyocardial High Power CO2 Laser Revascularisation (TMLR) as a last resource method for end-stage coronary disease patients.
Method And Patients: The High Power CO2 Laser 800 W Heart Laser (PLC Medical Systems) was used since February 1994 to treat 268 patients. In 52% of the cases (140) the indication for TMLR treatment was virtual inoperability by the classical bypass revascularisation.
The interaction between lymphocytes, cytokines, and endothelial cells (EC) is a key step in the inflammatory process. Interleukin-6 (IL-6) a pleiotropic cytokine in its effects, seems to be an early indicator of acute systemic inflammation. In this study, we have examined the effects of polyunsaturated fatty acids (PUFAs) on the production of IL-6 by human unstimulated EC or EC stimulated with TNF-alpha (100 U/ml); IL-4 (100 U/ml); LPS (1 ug/ml); or allogeneic peripheral blood lymphocytes (PBL).
View Article and Find Full Text PDFDietary supplementation with fish oil, which contains high amounts of long chain omega 3 ((n-3)) polyunsaturated fatty acids (PUFAs), particularly docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), has recently been shown to have protective and ameliorative effects on diseases characterized by chronic inflammatory reactions. Interactions between vascular endothelium, mononuclear cells, and cytokines are crucial steps in the course of inflammatory processes such as chronic graft rejection. We therefore studied the effects of DHA and EPA on both the adhesion of peripheral blood lymphocytes (PBL) to human endothelial cells (EC) in culture and the expression of EC-adhesion molecules and their counterreceptors on PBL.
View Article and Find Full Text PDFOnce hyperacute rejection has been prevented, the pig-to-human xenograft might be exposed to vascular cell-mediated rejection directed against vascular structures. In order to evaluate the relative importance of direct and antibody-dependent anti-endothelial cell-mediated cytotoxicity in different individuals, freshly isolated human blood leukocytes were incubated with confluent porcine aortic endothelial cells (PAEC) in a 4 h Cr-release cytotoxicity assay. Peripheral blood mononuclear cells (PBMC) and lymphocytes (PBL) of all subjects tested (but not monocytes or neutrophils) directly killed PAEC, with wide interindividual variations (from 2.
View Article and Find Full Text PDFConsidering that in the allogeneic situation the adhesion of recipient lymphocytes to donor endothelial cells initiates the cellular rejection, we questioned the possible occurrence of a similar process in the xenogeneic situation. The adhesion of human peripheral blood lymphocytes (PBL) to porcine aortic endothelial cells (PAEC) was thus studied in an in vitro porcine-to-human xenogeneic model. It was found that 25.
View Article and Find Full Text PDFBlood coagulation proteins were determined in 285 healthy fetuses from 19 to 38 weeks' gestation and compared with those of 60 normal full-term newborns and 40 adult controls. Prolongation of the coagulation screening tests, prothrombin time, activated partial prothrombin time, and thrombin clotting time, in fetuses throughout intrauterine life was explained by low levels of vitamin K-dependent factors (II, VII, IX, and X), contact factors (XI, XII, prekallikrein, and high-molecular-weight kininogen), factor V, factor VIII, and fibrinogen. Low levels of antithrombin III, heparin cofactor II, protein C and protein S, and tissue factor pathway inhibitor were also found, and these probably contributed to a satisfactory hemostatic balance.
View Article and Find Full Text PDFTo determine the role of the terminal alpha-galactosyl residue in the endothelial damage mediated by human xenoreactive natural antibodies (IgM and IgG), we treated porcine endothelial cells in culture with green coffee bean alpha-galactosidase. A practically complete removal of terminal alpha-Gal residues (as evaluated by flow cytometry with Bandeiraea simplicifolia isolectin B4) and concomitant exposure of N-acetyllactosamine were obtained without altering cell viability. A dramatic decrease in IgM and IgG binding (from a pool of human sera) was observed, confirming the key role of the alpha-galactosyl residues.
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