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S Kapiotis

Publications and source records attributed to S Kapiotis.

At least 109 records · Page 6Linked to original sources
PubMed1996

Increased levels of activated factor VII and decreased plasma protein S activity and circulating thrombomodulin during use of oral contraceptives.

In the present study the effect of oral contraceptive (OC) treatment on selected factors involved in the activation, i.e. circulating activated factor VII (cFVIIa), and in the inhibition of blood coagulation, i.e. plasma protein S activity and circulating thrombomodulin (cTM), were for the first time measured in OC users in a prospective study. Beside other coagulation variables, these parameters were measured during treatment with three low estrogen formulations containing different gestagen components (norgestimate, gestodene). During OC treatment increases in the activation markers prothrombin fragment F1 + 2 and D-Dimer were found, suggesting an increased activation of blood coagulation and fibrinolysis. Along with elevated plasma levels of FVII antigen, cFVIIa was also found increased in all three treatment groups, while inhibitory components of blood coagulation, plasma protein S activity and cTM, significantly and similarly decreased during treatment in all three treatment groups. We conclude that low dose estrogen pills induce similar changes in the plasma levels of main regulatory components of blood coagulation, despite differences in their gestagen components. Increased levels of activators and decreased activities of inhibitors may contribute to arterial and venous thrombotic complications seen in predisposed OC users.

Adult↗
PubMed1996

Influence of angiotensin II on circulating adhesion molecules and blood leukocyte count in vivo.

The mechanism of the beneficial effect of angiotensin converting enzyme inhibitors in patients with myocardial infarction is not clear. Recent in vitro data indicate that angiotensin II (AII) stimulates the expression of adhesion molecules and thus activates leukocyte endothelial interactions. In eight healthy volunteers we investigated the influence of exogenous AII on circulating adhesion molecules and on the blood leukocyte count. A systemically effective and a systemically ineffective dose of AII were administered intravenously over 4 h in a single blind crossover design. Examination of the time course of circulating intercellular and vascular adhesion molecules and E-selectin (cICAM-1, cVCAM-1, cE-selectin-1) in response to the AII infusion revealed increases of up to 11% (especially in cVCAM-1 levels) at single time points, but no significant sustained elevation or trend that can be interpreted as a drug-induced effect. The systemically effective dose, which induced an increase in mean arterial blood pressure from 80 to 108 mmHg (1 mmHg = 133.3 Pa), resulted in a significant increase in blood leukocytes, from 4.8 +/- 0.3 to 5.5 +/- 0.3 g/L (p < 0.05); the systemically ineffective AII dose did not alter blood leukocyte count significantly. Although we did not find an influence of AII on circulating adhesion molecules in vivo, we observed an increase in the blood leukocyte count; thus it may be intriguing to assess whether renin-angiotensin system modulating drugs might exert their favorable effect in ischemic diseases at least in part via an influence on leukocytes.

Adult↗
PubMed1995

Rapid elimination of a high-titer spontaneous factor V antibody by extracorporeal antibody-based immunoadsorption and immunosuppression.

We report on the rapid elimination of a potent spontaneous factor V antibody of undetermined etiology by extracorporeal immunoadsorption on sepharose-bound polyclonal sheep antibodies to human immunoglobulins (Ig-Therasorb, Baxter) in combination with immunosuppressive treatment. A 68-year-old woman presented with severe hematuria. Severe factor V deficiency (< 1%) caused by an antibody to factor V (26 BU/ml) was found. Extracorporeal immunoadsorption (8.245 +/- 553 ml plasma processed per session) led to an average reduction of the antibody titer by 75% per session. The procedure was well tolerated without any side effects. Hematuria ceased after three immunoadsorptions and complete elimination of the antibody was achieved after seven sessions (day 15), followed by a rapid increase of the factor V activity to normal levels. Treatment with cyclophosphamide and prednisone was started on day 6 and continued for 2 months. The patient remains in remission at 6 months. Extracorporeal immunoadsorption is a highly effective method for eliminating antibodies to factor V (or other clotting factors) in selected cases, i.e., in patients with severe bleeding tendency, high antibody titer, and low probability of a rapid spontaneous remission.

Aged↗
PubMed1995

Elimination of acquired factor VIII antibodies by extracorporal antibody-based immunoadsorption (Ig-Therasorb).

Treatment of potent factor VIII antibodies is a difficult problem. In some cases a reduction of the antibody titer is necessary for effective treatment with human factor VIII concentrates. We describe a new method for extracorporal elimination of factor VIII antibodies (antibody-based immunoadsorption). Blood is drawn from an antecubital vein, citrated, and plasma is separated with a rotating membrane. Plasma passes alternately through one of two columns filled with sepharose-coupled polyclonal sheep antibodies to human immunoglobulins (Ig-Therasorb), whereas the other column is regenerated. Each cycle has a duration of 15 min. Three patients with high titer factor VIII antibodies (one hemophiliac and 2 with spontaneous antibodies; titers 29, 132, and 313 BU/ml, respectively) were treated. The average reduction of the antibody titer was 76.1 +/- 17.2% per session. In each patient 4 sessions were necessary to reduce the antibody titer to < 1 BU/ml. The mean processed plasma volume was 6731 +/- 640 ml and the mean duration of each session 3.9 +/- 0.7 h. Serum IgG, IgA and IgM levels decreased by 75.3 +/- 11.9%, 62.9 +/- 19.1%, and 54.8 +/- 23.8% respectively. The procedure was tolerated without any side effects. Thus, rapid elimination of factor VIII inhibitors can be achieved with antibody-based immunoadsorption, which can be life-saving in some cases. This promising method should be evaluated in a larger number of patients.

Adult↗
PubMed1994

Functional characterization of cytokine autoantibodies in chronic renal failure patients.

We have recently reported on an increase of IL-1 alpha and IL-6 autoantibodies in patients maintained on chronic hemodialysis treatment. The aim of the present study was to evaluate functional properties of these autoantibodies. Serum samples of more then 500 chronic renal failure patients with and without replacement therapy were screened for the presence of IL-1 alpha and IL-6 autoantibodies by second antibody precipitation. The neutralizing capacity of IL-1 alpha autoantibody serum was studied by immunofluorescence flow cytometry analysis of IL-1 alpha induced expression of E-selectin (ELAM-1, CD62e) on HUVEC (human umbilical vein endothelial cells). Results of these inhibition studies were confirmed with IgG preparations from antibody positive sera, purified by affinity chromatography. Functional studies on IL-6-dependent B9 cell proliferation were performed with IL-6 autoantibody positive sera, and quantitated with the colorimetric MTT assay. IL-1 alpha induced expression of E-selectin on HUVEC (considered 100% positive cells) was inhibited by each IL-1 alpha autoantibody positive serum sample (N = 13; anti-IL-1 alpha activity: 7.62 to 57.52% binding). Inhibition of E-selectin expression by IL-1 alpha autoantibodies ranged from 0.11 to 80.22% positive cells (0.15 to 92.31% mean fluorescence intensity). A strong correlation of E-selectin expression with IL-1 alpha autoantibody concentration was observed (P < 0.005). Furthermore, IgG eluates from autoantibody positive patients inhibited E-selectin expression to 41.0 +/- 23.1% positive cells if compared with 83.7 +/- 5.7% positive cells of the IgG depleted serum samples.(ABSTRACT TRUNCATED AT 250 WORDS)

Autoantibodies↗
PubMed1994

Effect of hydroxyethyl starch on the activity of blood coagulation and fibrinolysis in healthy volunteers: comparison with albumin.

OBJECTIVE: The aim of this study was to investigate whether hydroxyethyl starch of medium molecular weight (200 daltons), compared with albumin, has specific effects on blood coagulation and fibrinolysis. DESIGN: A prospective, randomized, double-blind, crossover trial. SETTING: Laboratory at a university hospital. PATIENTS: Ten healthy male volunteers, 23 to 39 yrs old, with no history of hypersensitivity, who had normal physical examinations, and were free of a bleeding disorder. All patients did not ingest any medications for > or = 2 wks before or during the study period. INTERVENTION: Each volunteer received either 500 mL of hydroxyethyl starch (6% wt/vol, average molecular weight 200 kilodaltons, molar substitution 0.5 [ratio hydroxyethyl groups/glucose units] in 0.9% sodium chloride; average molecular weight of 200 kilodaltons) or a control of 500 mL of human albumin (5% albumin solution). After a washout period of 4 wks, subjects crossed over to the alternate treatment. MEASUREMENTS AND MAIN RESULTS: Blood samples were taken immediately before infusion and 20, 45, 75, 105, 165, 285, 405, and 1485 mins after the infusion started. Hematocrit, the blood coagulation parameters fibrinogen, activated partial thromboplastin time, factor VIII:C, thrombin-antithrombin III complexes, and the fibrinolytic parameters fibrin-split product D-Dimer, tissue type plasminogen activator, urokinase plasminogen activator, plasminogen activator inhibitor, and plasmin-antiplasmin complexes were measured. Except for factor VIII:C levels, which were significantly lower in the hydroxyethyl starch group, no other significant differences in the plasma levels of the parameters mentioned were detected between hydroxyethyl starch and albumin infusions. In one volunteer, who had a low initial factor VIII:C level of 51%, a decrease to 28% at 165 mins during hydroxyethyl starch infusion was found (corresponding albumin value at 165 mins was 41%). CONCLUSIONS: a) Medium molecular weight hydroxyethyl starch has a specific lowering effect on factor VIII:C concentrations; this phenomenon may be hazardous to patients who need full hemostatic competence and who receive medium molecular weight hydroxyethyl starch (e.g., as a plasma expander). b) Medium molecular weight hydroxyethyl starch does not specifically influence the activity of the fibrinolytic system.

Adult↗
PubMed1994

Modulation of pyrogen-induced upregulation of endothelial cell adhesion molecules (CAMs) by interleukin-4: transcriptional mechanisms and CAM-shedding.

The pyrogens interleukin 1 (IL-1), tumor necrosis factor (TNF), and bacterial lipopolysaccharides (LPS) are known to increase endothelial cell (EC) adhesiveness for leukocytes by stimulating surface expression of various adhesion molecules. IL-4, a product of activated T-cells, was shown to affect pyrogen-mediated regulation of EC adhesion molecule surface expression. In the present study, we investigated the effect of IL-4 on pyrogen-induced upregulation of the cell adhesion molecules (CAMs) ICAM-1 (intercellular cell adhesion molecule-1), ELAM-1 (endothelial leucocyte adhesion molecule-1), and VCAM-1 (vascular cell adhesion molecule-1) in cultured human umbilical vein EC (HUVEC). Surface expression of adhesion molecules was quantified by flow cytometry, HUVEC mRNA content was estimated by Northern blot analysis, and ICAM-1 antigen in conditioned media was measured by ELISA. Incubation of HUVEC with IL-1 (100 U/ml), TNF (500 U/ml), and LPS (10 micrograms/ml) caused significant increase in ICAM-1, ELAM-1, and VCAM-1 surface expression; IL-1 caused about an eightfold increase in ICAM-1 expression, about a 13-fold increase in ELAM-1 surface expression, and about a fourfold increase in VCAM-1 expression. Coincubation of pyrogens with IL-4 (500 U/ml) differentially influenced their proadhesive effects on the HUVEC surface. In the presence of IL-4, IL-1-induced ICAM-1 upregulation was reduced, ELAM-1 upregulation was not significantly influenced by IL-4, and induction of VCAM-1 was enhanced by IL-4.(ABSTRACT TRUNCATED AT 250 WORDS)

Base Sequence↗
PubMed1994

Early detection of hematopoietic engraftment after bone marrow and peripheral blood stem cell transplantation by highly fluorescent reticulocyte counts.

At present, the appearance of neutrophils in the peripheral blood is considered to be the earliest sign of hematopoietic regeneration after myeloablative chemoradiotherapy. We studied erythroid regeneration in 27 allogeneic and 21 autologous marrow recipients using an automated reticulocyte counter employing a flow cytometric technique. Thereby, reticulocytes can be divided into a high, moderate and low fluorescent fraction according to RNA content. Marrow ablation caused an immediate and rapid fall in highly fluorescent reticulocytes (HFR) to zero in all patients. HFR reappeared after a median time of 7 days after allogeneic and 11 days after autologous marrow grafting. This was 7 and 2 days earlier than the appearance of first neutrophils. In allogeneic marrow recipients given erythropoetin after marrow infusion the median time to reach HFR of 0.2 and 0.5 x 10(9)/l was significantly shorter than time to reach similar absolute neutrophil counts (ANC). In allogeneic marrow recipients treated with G-CSF time to rise of HFR and ANC was almost exactly the same. Thus, automated flow cytometric reticulocyte counting allows early detection of hematopoietic regeneration and may be of clinical value for the early diagnosis of inadequate marrow function after marrow transplantation and the monitoring of erythroid regeneration under cytokine administration.

Adolescent↗
PubMed1994

Rapid achievement of PML-RAR alpha polymerase chain reaction (PCR)-negativity by combined treatment with all-trans-retinoic acid and chemotherapy in acute promyelocytic leukemia: a pilot study.

The reverse transcriptase-polymerase chain reaction (RT-PCR) for the fusion transcript of PML-RAR alpha can be used to detect minimal residual disease (MRD) in acute promyelocytic leukemia (APL). We have applied a semi-quantitative two-step PCR assay (sensitivity: step 1 = 1 in 10(3) cells; step 2 = 1 in 10(6) cells) to monitor the dynamics of MRD after combined therapy with all-trans-retinoic acid (ATRA) and chemotherapy (CT) in 5 patients in whom complete clinical remission (CR) was achieved. The patients received an induction treatment with ATRA for 47, 40, 38, 14 or 10 days. In three patients ATRA was followed by CT. Two patients with hyperleukocytosis at diagnosis or after ATRA received an overlapping CT starting from day 3 or 7. Four of the five patients became two-step PCR-negative in their bone marrow within 43 to 82 days after onset of therapy. Two-step PCR-negatively was achieved with ATRA plus one course of CT in these four patients who are still in continuous complete remission after 19, 18, 7 and 5 months. One of these patients did not even receive consolidation CT because of congestive heart failure. The fifth patient remained second-step PCR-positive and relapsed after 5 months. Our results indicate that the combined regimen can rapidly reduce MRD below a detection limit of 1 in 10(6) cells within 1-3 months and that these results can even by achieved by a short course of ATRA together with only one cycle of CT.

Aged↗
PubMed1993

Studies on oral contraceptive-induced changes in blood coagulation and fibrinolysis and the estrogen effect on endothelial cells.

Blood coagulation (fibrinogen, thrombin-antithrombin III complexes, TAT, and prothrombin fragment F1 + 2) and fibrinolytic parameters [fibrin split-product D-dimer, tissue plasminogen activator (t-PA) activity, plasminogen activator inhibitor-1 activity (PAI-1), and plasmin-antiplasmin-complexes (PAP)] were evaluated in 16 women on low estrogen (EE) oral contraceptive (OC) therapy. Blood samples were taken before and between days 18 and 22 of the first, third, and sixth treatment cycle. Fibrinogen levels were found significantly elevated during OC treatment compared with pretreatment values, while TAT and also F1 + 2 levels remained unchanged. Treatment-induced activation of fibrinolysis was documented by elevated D-dimer [pretreatment (pt): 172 ng/ml (range: 65-640 ng/ml), cycle 6 (c.6): 351 ng/ml (range: 93-960 ng/ml), p < 0.05)] and PAP [(pt: 46.6 ng/ml (13-220 ng/ml), c.6: 66.4 ng/ml (21-200 ng/ml), p < 0.05] plasma levels. Among the fibrinolytic components a decrease in PAI-1 [pt: 10.8 ng/ml (2-56 ng/ml), c.6: 5.3 ng/ml (2.2-14.4 ng/ml), p < 0.05] and an increase in t-PA activity [pt: 0.23 U/ml (0.17-0.45 U/ml), c.6: 0.33 U/ml (0.2-0.9 U/ml), p < 0.05] were detected. Experiments with cultured human endothelial cells (EC) showed that EE influenced neither EC hemostatic regulatory activities (tissue factor, thrombomodulin) nor the secretion of the fibrinolytic components t-PA and PAI-1.

Adult↗
PubMed1993

Treatment of drug-induced agranulocytosis with recombinant granulocyte colony-stimulating factor (rh G-CSF).

Five patients with drug-induced agranulocytosis received 300 micrograms recombinant human granulocyte colony-stimulating factor (rh G-CSF) subcutaneously twice daily for 2-5 days. G-CSF therapy resulted in a steep increase of the neutrophil count, which was faster than that in patients with spontaneous recovery reported in the literature. In all four patients with infectious complications fever rapidly declined with the increase of granulocytes. G-CSF may be useful in the management of drug-induced agranulocytosis.

Adult↗
PubMed1993

Transient lupus anticoagulant associated with hypoprothrombinemia and factor XII deficiency following adenovirus infection.

A potent lupus anticoagulant (LA) was detected in four children, 1 week after the clinical onset of an adenovirus infection. The adenovirus infection was documented by direct virus detection in the stool of one patient and serologically in the others. None of the children had elevated titers of IgM- and only one of IgG-anticardiolipin antibodies (ACA). All patients had a marked reduction of prothrombin activity as well as antigen. Prothrombin-antibody complexes were demonstrated in the patients' plasma or mixtures of patient and normal plasma. Factor XII activity was moderately reduced in three of the patients. All coagulation abnormalities returned to normal within 4-12 weeks. Localized bleeding was observed in two cases, but there was no generalized bleeding tendency or evidence of thrombosis.

Adenoviridae Infections↗
PubMed1993

Molecular forms of pseudocholinesterase in patients with Crohn's disease.

Previous studies have shown that pseudocholinesterase (PCHE) is low in patients with Crohn's disease (CD). This finding, however, failed to be of clinical relevance due to the wide normal range. PCHE consists of four main molecular forms designated as C1, C2, C3 and C4 according to their electrophoretic mobility. The question of the present study was to assess the influence of CD on the distribution and pattern of the PCHE isozymes. We therefore investigated the electrophoretic separation of PCHE in 16 healthy volunteers (HV), in 15 patients with quiescent CD (QCD; CD activity index: median = 71, interquartile range = 44-122) and in 10 patients with active CD (ACD; CD activity index: 229, 173-304). In most of the cases total serum PCHE activity was within the normal range even in patients with active CD. No changes of the isozyme pattern were found but the percentage distribution was significantly influenced by the inflammatory activity in patients with active CD:C1 (HV: 14.7%, 13.7-18.1%; QCD: 16.0%, 9.8-19.9%; ACD: 8.5%, 2.9-12.5%, p < 0.01) and C2 (HV: 8.0%, 6.7-10.5%; QCD: 9.0%, 7.9-9.7%; ACD: 6.7%, 3.2-8.6%, p < 0.05) were decreased in active CD while the C4 component (HV: 66.8%, 62.5-69.9%; QCD: 63.1%, 54.9-73.8%; ACD: 77.3%, 70.7-90.1%, p < 0.01) was increased. The percentage of the C3 band (HV: 5.7%, 4.6-6.9%; QCD: 6.8%, 4.6-8.4%; ACD: 5.3%, 2.8-6.8%, NS) was unchanged.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Recurrent, isolated factor X deficiency in myeloma: repeated normalization of factor X levels after cytostatic chemotherapy followed by late treatment failure associated with the development of systemic amyloidosis.

We describe the case of a 64-year-old woman with isolated severe factor X deficiency associated with kappa light chain myeloma. At the time of diagnosis there was no evidence for amyloidosis. Complete remission (CR) of myeloma as well as normalization of factor X levels were achieved after cytostatic chemotherapy. Subsequently, factor X deficiency recurred twice without any evidence for relapse of myeloma. The first time factor X normalized again following cytostatic treatment, the second time, however, factor X deficiency was refractory to chemotherapy. Finally, relapse of myeloma became evident associated with rapidly progressing, systemic amyloidosis, which was fatal within a few months. Initially, factor X infusion studies showed a normal recovery, but when amyloidosis became overt the recovery decreased to 0%. We assume that factor X deficiency was due to a binding of factor X to kappa light chains associated with the proliferation of the malignant myeloma cell clone.

Amyloidosis↗
PubMed1991

Interleukin-4 counteracts pyrogen-induced downregulation of thrombomodulin in cultured human vascular endothelial cells.

Inflammatory mediators such as tumor necrosis factor (TNF) or interleukin-1 (IL-1) and bacterial lipopolysaccharides (LPS) were shown to shift the hemostatic balance of the endothelial cell (EC) surface in favor of procoagulant activities by inducing tissue factor (TF) expression and downregulation of thrombomodulin (TM). In the present study, the effects of IL-4 on these regulatory mechanisms were investigated using cultured human umbilical vein EC. TM downregulation induced by the pyrogens IL-1 (100 U/mL), TNF (500 U/mL), and LPS (20 micrograms/mL) to less than 50% of TM activity of untreated cells during a 12-hour incubation period was completely neutralized when these mediators were coincubated with IL-4 (100 U/mL). In accordance with TM surface activity, TM messenger RNA was decreased by IL-1, TNF, and LPS to less than 40% of untreated cells; this effect was in part antagonized by IL-4. No influence of IL-4 on EC tissue factor induction by IL-1, TNF, and LPS was found. Binding studies using 125I-radiolabeled IL-4 suggest that EC express a single class of high-affinity binding sites (kd = 3.2 pmol/L; 2,000 to 2,500 receptors per cell). These results show that IL-4, in part, protects the EC surface against pyrogen-induced procoagulant changes. Transcriptional regulatory mechanisms seem to be involved in EC surface TM regulation.

Cell Membrane↗
PubMed1991

Anticardiolipin antibodies in patients with venous thrombosis.

The levels of anticardiolipin antibodies (ACA) and lupus anticoagulant (LAC) were measured in 266 consecutive unselected patients with a history of venous thrombosis. 19 (7.1%) had elevated levels of IgG- or IgM-ACA. The prevalence of LAC was 1 of 266 (0.4%) in the whole patient group and 1 of 19 (5.3%) in the ACA-positive group. Patients with elevated ACA levels did not differ from those with normal ACA with regard to age at the first thrombosis, risk of recurrence, presence of arterial thrombosis, and other clinical features. 8 out of 19 (42.1%) patients with elevated ACA levels also had elevated levels of antinuclear antibodies, but only 1 fulfilled the criteria of systemic lupus erythematosus. These data indicate that in some patients with elevated ACA, autoimmune processes may be present. The clinical significance of elevated ACA levels is uncertain.

Adolescent↗