Activation of the complement cascade enhances motility of leukemic cells by downregulating expression of HO-1.

As a crucial arm of innate immunity, the complement cascade (ComC) is involved both in mobilization of normal hematopoietic stem/progenitor cells (HSPCs) from bone marrow (BM) into peripheral blood and in their homing to BM. Despite the fact that ComC cleavage fragments alone do not chemoattract normal HSPCs, we found that leukemia cell lines as well as clonogenic blasts from chronic myeloid leukemia and acute myeloid leukemia patients respond robustly to C3 and C5 cleavage fragments by chemotaxis and increased adhesion. This finding was supported by the detection of C3a and C5a receptors in cells from human malignant hematopoietic cell lines and patient blasts at the mRNA (reverse transcriptase-polymerase chain reaction) and protein level (fluorescence-activated cell sorting), and by the demonstration that these receptors respond to stimulation by C3a and C5a by phosphorylation of p42/44 and p38 mitogen-activated protein kinases (MAPK), and protein kinase B (PKB/AKT). We also found that inducible heme oxygenase 1 (HO-1) is a negative regulator of ComC-mediated trafficking of leukemic cells, and that stimulation of leukemic cells by C3 or C5 cleavage fragments activates p38 MAPK, which downregulates HO-1 expression, rendering cells more mobile. We conclude that activation of the ComC in leukemia/lymphoma patients (for example, as a result of accompanying infections) enhances the motility of malignant cells and contributes to their spread in a p38 MAPK-HO-1-dependent manner. Therefore, inhibition of p38 MAPK or upregulation of HO-1 by small-molecule modulators would have a beneficial effect on ameliorating cell migration-mediated expansion of leukemia/lymphoma cells when the ComC becomes activated.

Efficacy and safety of lenalidomide treatment in multiple myeloma (MM) patients--Report of the Polish Myeloma Group.

UNLABELLED: The aim of the multi-centre retrospective study was to evaluate the efficacy and safety of lenalidomide (LEN) therapy in patients with resistant or relapsed multiple myeloma (MM) as well as in patients with stable disease (LEN used due to neurological complications). The primary endpoint of this study was an overall response rate (ORR). The secondary endpoints were as follows: time to progression (TTP), overall survival (OS) and the safety of drug use. Data were collected in 19 centres of the Polish Multiple Myeloma Study Group. The study group consisted of 306 subjects: 153 females and 153 males. In 115 patients (38.8%, group A), a resistant myeloma was diagnosed; in 135 (44.1%, group B) a relapse, and in 56 (18.3%, group C) a stable disease were stated. In 92.8% of patients, LEN+DEX combination was used; in remaining group, LEN monotherapy or a combination therapy LEN+bortezomib or LEN+bendamustine and other were used. In the entire study group, ORR was 75.5% (including 12.4% patients achieving complete remission [CR] or stringent CR [sCR]). Median time to progression (TTP) was 20 months. Median overall survival (OS) was 33.3 months. The regression model for "treatment response" was on the borderline of statistical significance (p=0.07), however the number of LEN treatment cycles ≥ 6 (R(2)=17.2%), baseline LDH level (R(2)=1.1%) and no ASCT use (R(2)=1.7%) where the factors most affecting treatment response achievement. The regression model for dependant variable--"overall survival"--was statistically significant (p=0.0000004). Factors with the most impact on OS were as follows: number of LEN cycles treatment ≥ 6 (R(2)=16.7%), treatment response achievement (R(2)=6.9%), ß-2-microglobulin (ß-2-M) level (R(2)=4.8%), renal function (R(2)=3.0%) and lack of 3/4 grade adverse events (R(2)=1.4%). SUMMARY: LEN is an effective and safe therapeutic option, even in intensively treated resistant and relapsed MM patients, as well as in patients with stable disease and previous treatment-induced neurological complications. In particular, the number of LEN treatment cycles ≥ 6 was the factor which affected treatment response achievement the most, together with an important impact on OS.

Prognostic significance of ligands belonging to tumour necrosis factor superfamily in acute lymphoblastic leukaemia.

Altered activities of ligands belonging to tumour necrosis factor (TNF) superfamily, namely B-cell activating factor (BAFF), a proliferation-inducing ligand (APRIL) and apoptosis inducing ligand (TRAIL) were demonstrated in several haematological diseases including acute lymphoblastic leukaemia (ALL). BAFF, APRIL and TRAIL provide crucial survival signals to immature, naive and activated B cells. These ligands are capable of activating a broad spectrum of intracellular signalling cascades that can either induce apoptosis or protect from programmed cell death. BAFF and APRIL, which can directly activate the NF-κB pathway, have been identified as crucial survival factors for ALL cells. Here, we have analyzed serum BAFF, APRIL and TRAIL concentrations in 48 patients with newly diagnosed ALL and 44 healthy volunteers. The levels of APRIL and BAFF were significantly higher in ALL patients as compared to healthy volunteers. In contrast, concentrations of TRAIL were significantly lower in ALL patients. Moreover, following induction, the levels of APRIL, but not BAFF or TRAIL, were significantly lower in a group of patients with complete remission (CR) as compared to non-respondent (NR) ALL patients. Furthermore, we demonstrated statistically significant differences in concentrations of APRIL between CR MRD-negative and CR, MRD-positive ALL patients. Notably detection of higher concentrations of APRIL was associated with shorter leukaemia-free survival and overall survival. Altogether, our data indicate that APRIL can play an important role in the pathogenesis of ALL and the measurement of APRIL levels can improve prognostication in ALL patients.

The impact of TNF superfamily molecules on overall survival in acute myeloid leukaemia: correlation with biological and clinical features.

B cell-activating factor (BAFF), a proliferation-inducing ligand (APRIL) and apoptosis-inducing ligand (TRAIL) were demonstrated in several haematological diseases including acute myeloid leukemia (AML). Those cytokines are capable of activating a broad spectrum of intracellular signalling cascades that can either induce apoptosis or protect from programmed cell death. We have analysed BAFF, APRIL and TRAIL serum concentrations in 76 patients with newly diagnosed AML and 40 healthy volunteers. The values were significantly higher for APRIL and BAFF but lower for TRAIL compared to healthy volunteers. Induction therapy significantly reduced the values for BAFF and increased them for TRAIL. Moreover, the concentration of BAFF and APRIL was significantly lower and the concentration of TRAIL higher in a group of patients with complete remission compared to non-respondent AML patients. In addition, higher concentrations of BAFF and lower of TRAIL predicted a shorter overall survival, suggesting thereby an important prognostic marker and possible therapeutic target in AML.

BAFF and APRIL as TNF superfamily molecules and angiogenesis parallel progression of human multiple myeloma.

Tumour necrosis factor alpha (TNF-α) is an inflammatory cytokine with a wide spectrum of biological activity, including angiogenesis. B cell activating factor (BAFF) and a proliferation-inducing ligand (APRIL) are members of the TNF-α family. Vascular endothelial growth factor (VEGF), on the other hand, is one of the most characteristic pro-angiogenic cytokines produced by multiple cell types in multiple myeloma (MM). We have analysed BAFF and APRIL concentrations in parallel with pro-angiogenic cytokines in serum and trephine biopsy, and the bone marrow microvascular density (MVD) in 50 patients with newly diagnosed IgG MM and 24 healthy volunteers. The study showed statistically higher concentrations of BAFF, APRIL and TNF-α, as well as VEGF and its receptor, in MM patients compared to healthy volunteers and patients in advanced stages of the disease. A statistically positive correlation between the concentration of TNF-α and the expression of VEGF was demonstrated, and so was a positive link between BAFF, APRIL, MVD and lactate dehydrogenase (LDH). Furthermore, we observed a significant decrease in all studied cytokines after anti-angiogenic therapy, with meaningful differences between responders (at least partial remission) and patients with stable disease. It was also established that APRIL, but not BAFF, correlated with pro-angiogenic cytokines such as VEGF with its receptor, MVD and syndecan-1. Finally, our results showed that serum BAFF and APRIL levels could be useful biomarkers of MM disease activity and its progression which suggests that APRIL could be a possible novel therapeutic target in MM.

The evaluation of angiogenesis and matrix metalloproteinase-2 secretion in bone marrow of multiple myeloma patients before and after the treatment.

PURPOSE: Angiogenesis appears to be a prominent feature of many hematological disorders, particularly in multiple myeloma (MM). Progression in MM also involves secretion of the metaloproteinases (MMPs). In this study, the expression of vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF) and its receptor, in bone marrow trephine biopsy (TB) of thirty six MM patients before and after the treatment or during progression was examined. The MMP-2 secretion was assessed from the same patients. MATERIAL/METHODS: Immunohistochemical staining of bone marrow specimens for angiogenic factors and microvessel density (MVD) and bone marrow aspirates for Western blot analysis of MMP-2 expression was performed. RESULTS: In active, untreated MM patients, we found statistically significant differences in the expression of angiogenic factors according to the patients after the anti-angiogenic treatment. We found statistical differences of the expression of angiogenic factors between the group of patients with a response after the treatment and the patients who had progression during the treatment. The data showed statistically significant decreased MVD after the treatment. The results showed statistically significant differences between initial secretion of MMP-2 in active, untreated MM patients and patients with a response after the treatment and patients with progression during the treatment. CONCLUSIONS: We showed that not only decreased expression of angiogenic cytokines is present after the anti-angiogenic treatment but also activity of MMP-2 in MM patients who responded to the treatment. Combination therapy with the inhibition of the activity of MMPs could represent an interesting therapeutical approach in MM.

Clinical assessment of Optivate®, a high-purity concentrate of factor VIII with von Willebrand factor, in the management of patients with haemophilia A.

Factor VIII (FVIII) concentrates have revolutionized the treatment of patients with haemophilia A. Concerns over the transmission of viral infections through these products have been addressed through stringent, donor-screening procedures and robust antiviral manufacturing steps. Bio Products Laboratory has developed a high-purity FVIII product with von Willebrand factor, Optivate(®). Its safety, tolerability and efficacy as prophylaxis and treatment of bleeds have been established in long-term studies. Seventy previously treated patients with severe haemophilia A, with ≥ 20 exposure days, were recruited into two long-term, multicentre, open-label studies. The protocols were virtually identical. Patients received Optivate(®) either prophylactically or on-demand. A mean of 159.0 EDs were experienced over 11,320 infusions. Under both conditions, Optivate(®) was well tolerated. Only 10% of patients experienced a treatment-related adverse event; the most commonly reported were headache (4% of patients) and dizziness (3% of patients). The mean number of bleeds/patient over the 2 year treatment period was 23.5 during prophylactic use and 70.4 during on-demand use. In patients treated prophylactically, clinical responses to breakthrough bleeds were rated by physicians as excellent or good and as very helpful or helpful by patients in 95% of bleeds. Clinical responses for on-demand patients were rated as excellent or good by physicians and helpful or very helpful by the patients for 91% of bleeds. There were no viral transmissions or inhibitors. The studies confirm the clinical efficacy and safety of Optivate(®) in both prophylactic and on-demand management of patients with haemophilia A.

Pharmacokinetics of Optivate(®), a high-purity concentrate of factor VIII with von Willebrand factor, in patients with severe haemophilia A.

Optivate(®) is a high purity factor VIII/von Willebrand factor (FVIII/VWF) concentrate, which is manufactured using two antiviral processes: solvent/detergent and terminal dry heating (80 °C for 72 h). A multicentre, non-randomized open-label study in 15 patients was conducted to test the pharmacokinetics (PK) of Optivate(®). PK variables were analysed for the patients' prior FVIII product (PK1), their first dose of Optivate(®) (PK2) and at 3 months therapy (PK3). Mean non-compartmental half-lives (h) were 14.1, 12.4 and 12.1, respectively (P = 0.45), mean clearances (mL h(-1) kg(-1)) were 3.6, 3.2 and 3.1, respectively (P = 0.051), MRTs (h) were 19.0, 17.3 and 17.4, respectively (P = 0.39) and mean AUC(0-48h) (h IU mL(-1)) were 14.3, 15.4 and 16.6, respectively (P = 0.051) and mean AUC(0-∞) (h IU mL(-1)) were 15.9, 16.4 and 17.9, respectively (P = 0.18). The recovery data from this PK study was aggregated with recovery data collected from another study, with similar design but devoid of the other PK measurements. A total of 309 recoveries were conducted in 70 patients. The overall mean recovery per subject across 27 Optivate(®) batches was 2.7 IU dL(-1) per IU kg(-1). There were no clinical differences between Optivate(®) and other FVIII products, and except for volume of distribution (Vd), no statistically significant differences were seen with respect to any of the other PK variables, or in recovery between weeks 0 and 12. Therefore, the PK of FVIII is not affected by the processes used to manufacture Optivate(®), which can be expected to be effective in the management of patients with haemophilia A.

Evaluation of TNF superfamily molecules release by neutrophils and B leukemic cells of patients with chronic B - cell lymphocytic leukemia.

It was demonstrated that TNF superfamily proteins may affect significantly the time of leukemic cells' survival in the course of B-cell chronic lymphocytic leukemia (B-CLL). The aim of our study was to evaluate the expression and release of BAFF (B-cell activating factor), APRIL (a proliferation-inducing ligand) and TRAIL (TNF-related apoptosis inducing ligand) molecules belonging to the cytokines of the superfamily of the tumor necrosis factor (TNF) by neutrophils (PMNs) and, for comparison, B cells isolated from the blood of patients with B-CLL vs. their concentration in the blood serum. 40 patients suffering from B-CLL and a control group of 15 healthy subjects were included in the study. Cytoplasmic fractions of PMNs and B cells were analyzed with the use of western blotting for the presence of TRAIL, BAFF and APRIL. Soluble TRAIL, BAFF and APRIL in the culture supernatants and the serum were assessed using ELISA kits. PMNs and B cells of patients with B-CLL before treatment demonstrated the statistically significantly higher expression of APRIL and BAFF proteins when compared with the control group of healthy subjects. In contrast, the expression of TRAIL protein in both types of cells of patients was statistically significantly lower than its expression in the control cells. In the supernatants of PMN and B lymphocytes of patients the decreased concentrations of sBAFF, unchanged of APRIL and increased of sTRAIL molecules were demonstrated. The results of studies carried out in patients with B-CLL before treatment indicate that the relations demonstrated between APRIL, BAFF and TRAIL molecules, released by neutrophils and B cells and relations between their concentrations in the serum can significantly influence the development of B-CLL.

Cannabinoid receptors expression in bone marrow trephine biopsy of chronic lymphocytic leukaemia patients treated with purine analogues.

BACKGROUND: Cannabinoid receptors CB1 and CB2 are part the endocannabinoid system that plays an important role in the process of proliferation and apoptosis of different neoplastic cells. B-cell chronic lymphocytic leukaemia is one of the diseases in which these processes are altered. AIM: The aim of our study was the assessment of cannabinoid receptor expression on the B-lymphocytes in bone marrow trephine biopsy from leukaemic patients at diagnosis and after purine analogue treatment. METHODS: The biopsy was taken routinely and standard immunohistochemical staining procedure for paraffin embedded sections was applied. The cannabinoid receptors were detected using specific primary polyclonal antibody anti-CB1 and anti-CB2. Additionally, an existence of cannabinoid receptors was confirmed by flow cytometry. RESULTS: The results showed that the expression of CB1 receptor on the surface of neoplastic cells was lower than that of CB2 (17.0+/-3.1% and 92.1+/-1.7% respectively, p<0.001). Nine of the patients responded to applied treatment with a reduction in leukaemic infiltration (77.2+/-6.9% to 30.2+/-6.5%, p=0.007) and CB1 receptor expression (24.4+/-4.8% to 8.6+/-2.9%, p=0.01), but there was no change in CB2 expression (91.7+/-2.7% vs 90.9+/-2.8%, p=0.69). Four patients without remission expressed even greater number of the receptors. In all of the cases both cannabinoid receptor types antibodies gave positive reaction. Furthermore, the existence of cannabinoid receptors on neoplastic lymphocytes was confirmed by flow cytometry. CONCLUSION: The study provides original evidence for the existence of cannabinoid receptors on B-lymphocytes in chronic lymphocytic leukaemia patients. The receptors are thought to be a new structure that can modify the course of the disease and may be considered as a new target in leukaemia treatment.

Carbohydrate-deficient isoforms of transferrin (%CDT) and sialic acid (SA) in iron-deficiency anemia.

This study has investigated the serum levels of carbohydrate-deficient isoforms of transferrin (CDT) and sialic acid (SA) in iron-deficiency anemia (IDA). Blood samples were collected from 60 women with IDA and from 20 healthy controls. CDT was estimated by anion-exchange chromatography on minicolumns followed by photometric detection of transferrin and was expressed as a percentage of total transferrin (%CDT). SA was measured by an enzymatic method. There was no difference in the mean level of %CDT between patients with IDA (2.26%) and control patients (2.05%). SA increased significantly from control level 0.61 to 0.69 g/l in anemic patients. We concluded that elevated concentration of total transferrin in IDA did not change the relative value of low sialylated isoforms (%CDT) and the increase of total SA level in the sera of anemic patients is not related to the increase of total transferrin.

The effect of continuous-flow automated plateletpheresis on fibrinolytic activity of donor plasma.

Blood circulating in extracorporeal circuit of the apheresis sets has a contact with an artificial surface. The data on the influence of plateletpheresis on fibrinolytic activity are very limited and difficult to interpret. The aim of our study was to estimate the effect of plateletpheresis on the activation of fibrinolysis. Plateletpheresis was performed in 17 healthy blood donors using continuous-flow cell separator COM.TEC (Fresenius, Bad Homburg, Germany). Before and after plateletpheresis, blood samples were taken and markers of fibrinolysis (PAP, t-PA, PAI-1) as well as factor XII activity have been measured. We observed statistically significant decrease in t-PA and factor XII activities after plateletpheresis. There were no significant changes in concentrations of t-PA, PAI-1 and PAP as well as PAI-1 activity after plateletpheresis. Plateletpheresis performed by COM.TEC cell separator has very little, if any, effect on the activation of fibrinolysis. The mechanism of the inhibition of t-PA activity needs further investigations.

An evaluation of factors predicting long-term response to thalidomide in 234 patients with relapsed or resistant multiple myeloma.

The aim of this study was to assess the prognostic value of pretreatment clinical and laboratory parameters in refractory or relapsed multiple myeloma (MM) patients who have a long-term response to thalidomide (THAL), lasting at least 18 months. The study was carried out on 234 patients who received THAL for relapsed/refractory myeloma. Out of the 234 patients, 129 patients (55.1%) responded to THAL with a mean response duration of 11.9 months (ranging from 1 to 48) and an overall survival rate of 20.3 months (ranging 1-55 months). In 64 patients (27.4% of the whole group), the response to THAL lasted > or =18 months with a mean response lasting 24 months. Statistical analysis of the group of nonresponders and patients with long-term response to THAL showed a significantly higher serum albumin level (P=0.0003) and haemoglobin level (P=0.05), as well as a lower beta2 microglobulin (beta2M) (P=0.022), LDH (P=0.045) serum level in patients with long-term response. In this study, the LDH and serum albumin level were predictors for response to THAL therapy. The beta2M serum level was not a predictor for response to THAL. The albumin serum level was the best parameter distinguishing the group of patients with long-term response to THAL from the entire responding group (P=0.02).

Efficacy and safety of fludarabine and cyclophosphamide combined therapy in patients with refractory/recurrent B-cell chronic lymphocytic leukaemia (B-CLL)-Polish multicentre study.

The aim of this study was to investigate the efficacy of a combination of fludarabine (F) and cyclophosphamide (C) in the treatment of patients with refractory/recurrent B-cell chronic lymphocytic leukaemia (B-CLL). Between November 1999 and December 2001, 63 patients with B-CLL (median age 60 years) received a regimen that consisted of F 25 mg/m2 and C 250 mg/m2, days 1-3, intravenously, every 4 weeks, for a maximum of 6 courses, Response and toxicity were assessed according to current criteria (NCI-WG and WHO). Complete and partial remissions were achieved in 17.5% and 55.6% of patients, respectively; 19% of patients had stable disease and 7.9% of patients showed disease progression. The median follow-up was 16.5 (range 1.5-32) months. The median duration of progression-free survival (PFS) has not been reached among patients treated with FC regimen as second-line therapy. The median PFS was 13 (range 8-26) months in the 19 responding patients treated with FC regimen as third-line therapy. The most frequent side-effects were neutropenia (45%), thrombocytopenia (42%) and infections (57%). We conclude that the combination of fludarabine and cyclophosphamide demonstrated significant efficacy in pretreated, advanced B-CLL patients, with tolerable toxicity.

Addition of cladribine to daunorubicin and cytarabine increases complete remission rate after a single course of induction treatment in acute myeloid leukemia. Multicenter, phase III study.

To assess the efficacy of an original DAC-7 regimen: daunorubicine (DNR) 60 mg/m2/day, days 1-3; cytarabine (AraC) 200 mg/m2/day, days 1-7; cladribine (2-CdA) 5 mg/m2/day, days 1-5, 400 untreated adult acute myeloid leukemia patients (including 63 with preceding myelodysplastic syndrome), aged 45 (16-60) years were randomized to either DAC-7 (n=200) or DA-7 (without 2-CdA, n=200). The overall CR rate equaled 72% for DAC-7 and 69% for DA-7 arm (P=NS). After a single course of DAC-7 induction, the CR rate equaled 64% and was significantly higher compared to 47% in the DA-7 arm (P=0.0009). Median hospitalization time during the induction was 7 days shorter for DAC-7 compared to the DA-7 group (33 vs 40 days, P=0.002). Toxicity was comparable in both groups. The probability of 3-year leukemia-free survival (LFS) for DAC-7 and DA-7 group equaled 43 and 34%, respectively (P=NS). There was a trend toward higher LFS rate for patients aged >40 years receiving DAC-7 compared with DA-7 regimen (44 vs 28%, P=0.05). This study proves that addition of 2-CdA increases antileukemic potency of DNR+AraC regimen, thus resulting in a higher CR rate after one induction cycle when compared to DA-7, without additional toxicity. It shortens hospitalization time and may improve long-term survival in patients aged >40 years.

Influence of thalidomide on megakaryocytes in multiple myeloma.

The aim of the study was to assess the influence of thalidomide on megakaryocytes (MK) in patients with multiple myeloma (MM). The study was based on bone marrow trephine biopsies from 12 patients with MM before initiation of thalidomide administration and after three months of its duration. The morphometric examinations were done, using image analysis (DP 12). Quantitative assessment of MK and the analysis of the morphological parameters of MK were performed. MK with features of dysplasia were more frequently observed before the treatment. Additionally, a greater number of the so-called 'naked nuclei' was noticed then. Due to the effect of thalidomide, the mean number of MK increased and so did their area. During the treatment, a more frequent presence of emperipolesis was observed. The observations confirm the fact that thalidomide may cause changes in MK.

The rate of apoptosis and expression of Bcl-2 and Bax in leukocytes of acute myeloblastic leukemia patients.

The rate of apoptosis as well as expression of Bcl-2 and Bax was evaluated before and after induction therapy in leukocytes of 70 patients with acute myeloblastic leukemia (AML), retrospectively divided into group A (with longer survival) and group B (with shorter survival). We found, that leukocytes of untreated AML patients showed susceptibility to apoptosis similar to control cells. Marked increase in percentage of apoptotic leukocytes was observed after induction therapy exclusively in patients with longer survival, which was accompanied by better normalization of routine hematological parameters. In this group, the Bcl-2/Bax ratio was similar to the control and remained unchanged after treatment. In AML patients with shorter survival, a twofold increase in this ratio was observed both before and after the completion of induction therapy. In both groups of untreated patients, western blot analysis revealed the presence of prominent additional bands reacting with anti-Bcl-2 or anti-Bax antibody, which were undetectable in control leukocytes. After the therapy, these bands disappeared, especially in patients from group A. In conclusion, the lack of therapy-induced enhancement in leukocyte apoptosis, an increased ratio of Bcl-2/Bax as well as persistent presence of abnormal Bcl-2 and Bax protein bands after induction therapy in AML patients may be considered as factors associated with unfavorable clinical outcome.

Changes in the extrinsic and intrinsic coagulation pathways in humans after decompression following saturation diving.

We have investigated the effect of simulated saturation diving on the activation of intrinsic and extrinsic coagulation pathways. Thirty-one male divers divided into two groups were tested in decompression habitat LSH-200. The first group of 16 divers was subjected to hyperbaric exposure at pressure of 180 kPa with air as a breathing mixture, and the second group of 15 divers, exposed to a pressure of 400 kPa with a heliox breathing mixture (helium-oxygen mixture: pO2, 40 kPa; pN2, 40 kPa; pHe, 420 kPa). The concentrations of tissue factor, tissue factor pathway inhibitor, factors XII, X, VII, and I, prothrombin fragment F1 + 2, and thrombin-antithrombin complex as well as platelet count, prothrombin time, activated partial thromboplastin time, plasmin-antiplasmin complex (PAP) and D-dimers were measured. We did not detect activation of the extrinsic coagulation pathway after decompression. There was a statistically significant decrease in platelet counts and factor I, XII and X concentrations after air-diving, and a potent and statistically significant increase of PAP concentration in both groups of divers. We suggest that saturated air or heliox diving followed by decompression have little if any effect on thrombin generation. Saturated air diving, however, may induce a decrease in platelet count and factor XII concentration. The observed elevation of PAP concentrations in both groups of divers suggests possible activation of fibrinolysis. The exact effect of diving and decompression on fibrinolytic system has to be further investigated.

[Activation of hemostasis in patients with chronic cholecystitis]. / Aktywacja hemostazy u chorych na przewlekle kamicze zapalenie pecherzyka zólciowego.

The aim of the study was to evaluate the influence of chronic cholecystitis on haemostasis. The study was conducted on 48 patients suffering from chronic cholecystolithiasis admitted for cholecystectomy to the Department of Surgery Regional Hospital in Bialystok. The control group consisted of 25 healthy subjects in this same age range. As a result of the study we found out that patients with chronic cholecystitis had hypercoagulability characterised by increase plasma concentrations of the sensitive markers of haemostasis: prothrombin fragments (F1 + 2), thrombin/antithrombin complex (TAT) and D-dimer.

[Tissue factor and it's inhibitor in patients up to 50 years of age with ischemic stroke]. / Czynnik tkankowy i jego inhibitor u chorych do 50 roku zycia z niedokrwiennym udarem mózgu.

Stroke is the third leading cause of death and an important cause of longterm disability. Up to 10% of stroke patients is younger than 45 years old. In the present study we measured and compared TF and TFPI concentrations in 50 ischemic stroke patients up to the age of fifty and in 30 control subjects matched for age. TF concentration was significantly higher in ischemic stroke patients, TFPI concentration did not differ compared to controls. No relationship was established between TF and TFPI in relation to clinical subtypes of stroke, sex, smoking, plasma cholesterol level, hypertension, previous stroke.