Adipokines as atherothrombotic risk factors in obese subjects: Associations with haemostatic markers and common carotid wall thickness.

BACKGROUND AND AIMS: Some crucial associations between obesity-related altered adipokine levels and the main factors of atherosclerotic, atherothrombotic processes are not fully known. We analysed the relationships of classic adipokines, namely leptin, resistin, adiponectin, tumour necrosis factor-alpha (TNF-α), interleukin 6 (IL-6) with the markers of platelet activation, including mean platelet volume (MPV), platelet surface/soluble P-selectin, platelet-derived microparticles (PMPs), the parameters of coagulation abnormalities and common carotid intima-media thickness (IMT) in obese patients with or without atherosclerotic comorbidities in comparison to age- and sex-matched controls. METHODS AND RESULTS: We enrolled 154 obese individuals, including 98 suffering from atherosclerotic concomitant conditions, 56 free of atherosclerotic comorbidities and 62 healthy controls. Plasma levels of leptin, resistin, adiponectin, TNF-α, IL-6, soluble P-selectin, and plasminogen activator inhibitor-1 antigen (PAI-1 ag) were analysed by ELISA. Platelet surface P-selectin and PMPs were measured by flow cytometry. IMT was detected by ultrasonography. Adipokines were closely associated with markers of platelet hyperactivity, hypercoagulability, hypofibrinolysis and IMT. Significant independent associations were found between leptin and platelet count (p < 0.0001), MPV (p = 0.019), PMPs (p < 0.0001), fibrinogen (p = 0.001), factor VIII (FVIII) activity (p = 0.035); adiponectin and PAI-1 ag (p = 0.035); resistin and soluble P-selectin (p = 0.002); TNF-α and PAI-1 ag (p < 0.0001); and IL-6 and fibrinogen (p = 0.011). Finally, leptin (p = 0.0005), adiponectin (p = 0.019), IL-6 (p = 0.001), MPV (p = 0.0003), PMP (p = 0.008), and FVIII activity (p = 0.043) were independent predictors of IMT. CONCLUSION: Overall, we suggest that in obese subjects altered adipokine levels play a key role in common carotid atherosclerosis both directly and through haemostatic parameters.

Prevalence and seasonal variation of hypovitaminosis D and its relationship to bone metabolism in healthy Hungarian men over 50 years of age: the HunMen Study.

UNLABELLED: This study reports a high prevalence of hypovitaminosis D and low bone mineral density (BMD) in a healthy Hungarian male cohort over 50 years of age. Men with 25-hydroxyvitamin D levels of <75 nmol/L had a significantly higher 10-year hip and major osteoporotic fracture probability using the country-specific fracture risk assessment (FRAX) algorithm. INTRODUCTION: The aim of this study is to characterize the prevalence and seasonal variation of hypovitaminosis D and its relationship to bone metabolism in healthy Hungarian men over 50 years of age. METHODS: We determined levels of 25-hydroxyvitamin D (25-OH-D), PTH, osteocalcin (OC), C-terminal telopeptides of type-I collagen (CTX-I), procollagen type 1 amino-terminal propeptide (PINP), BMD at L1-L4 (LS) and femur neck (FN), daily dietary calcium intake, and the 10-year probability of hip fracture and a major osteoporotic fracture using the country-specific FRAX algorithm in 206 randomly selected ambulatory men. RESULTS: The mean (range) age of the volunteers was 60 (51-81) years. The prevalence of hypovitaminosis D (25-OH-D, <75 nmol/L) was 52.9%. The prevalence of low (T-score < -1.0) BMD at the FN and LS was 45% and 35.4%, respectively. The mean (range) FRAX hip fracture and FRAX major osteoporotic fracture was 0.8% (0-9.4%) and 3.8% (1.7-16%), respectively. On comparing the vitamin D sufficient to the insufficient group, there was a statistically significant difference between the FRAX hip fracture and FRAX major osteoporotic fracture indexes. There was significant seasonal variation in the vitamin D levels; the lowest levels were measured in winter and the highest in summer. CONCLUSIONS: A high prevalence of hypovitaminosis D and low BMD were observed in the studied Hungarian male population. This is the first study reporting higher 10-year hip and major osteoporotic fracture probability using the country-specific FRAX algorithm in individuals with hypovitaminosis D.

Impaired regulatory T-cell homeostasis due to vitamin D deficiency in undifferentiated connective tissue disease.

OBJECTIVE: The aim of this study was to perform a quantitative and functional analysis of natural CD4+CD25(high)Foxp3+ regulatory T cells (nTregs) and CD4+IL-17+ T cells, and to assess the serum levels of proinflammatory cytokines in patients with undifferentiated connective tissue disease (UCTD) before and after 5 weeks of 0.5 µg/day alfacalcidol supplementation. METHODS: Twenty-five patients with UCTD were enrolled in an open-label trial of alfacalcidol. Plasma levels of 25-hydroxyvitamin D [25(OH)D] were assessed by a high-performance liquid chromatography (HPLC) method. Flow cytometry was used for the quantification of nTregs and the IL-17 expression of T-helper (Th)17 cells. The serum concentrations of cytokines interleukin (IL)-12, interferon (IFN)-γ, IL-23, IL-17, IL-6, and IL-10 were measured by an enzyme-linked immunosorbent assay (ELISA). RESULTS: Treatment with alfacalcidol raised 25(OH)D levels from a mean of 23.5 ± 5.6 to 34.5 ± 7.4 ng/mL (p = 0.059; NS). Alfacalcidol treatment decreased both Th1- (IL-12 and IFN-γ) and Th17-related (IL-23, IL-17, IL-6) cytokine levels in UCTD patients, while the soluble IL-10 level increased (IL-12: 156.7 ± 75.2 vs. 87.5 ± 42.1 pg/mL, p < 0.001; IFN-γ: 41.5 ± 12.0 vs. 21.7 ± 9.9 pg/mL, p < 0.001; IL-23: 385.2 ± 82.2 vs. 210.0 ± 69.3 pg/mL, p < 0.001; IL-17: 37.8 ± 9.6 vs. 17.8 ± 4.5 pg/mL, p = 0.009; IL-6: 39.4 ± 11.3 vs. 23.5 ± 6.3 pg/mL, p < 0.001, IL-10: 8.4 ± 3.0 vs. 21.4 ± 9.7 pg/mL, p < 0.001). Alfacalcidol improved the Th17/nTreg imbalance, as it inhibited the IL-17 expression of Th17 cells, and increased the number of nTregs. The alfacalcidol might increase the capacity of nTreg cells to suppress the proliferation of autologous CD4+CD25⁻ cells. CONCLUSION: Our findings support the idea that vitamin D influences the Th17/nTreg imbalance in vitamin D-insufficient patients with UCTD and could be beneficial in the management of the disease.

Discriminant function analysis as decision support system for the diagnosis of acute leukemia with a minimal four color screening panel and multiparameter flow cytometry immunophenotyping.

Despite several recommendations for standardization of multiparameter flow cytometry (MFC) the number, specificity and combinations of reagents used by diagnostic laboratories for the diagnosis and classification of acute leukemias (AL) are still very diverse. Furthermore, the current diagnostic interpretation of flow cytometry readouts is influenced arbitrarily by individual experience and knowledge. We determined the potential value of a minimal four-color combination panel of 13 monoclonal antibodies (mAbs) with a CD45/sideward light scatter-gating strategy for a standardized MFC immunophenotyping of the clinically most relevant subgroups of AL. Bone marrow samples from 155 patients with acute myeloid leukemia (AML, n=79), B-cell precursor acute lymphoblastic leukemia (BCP-ALL, n=29), T-cell precursor acute lymphoblastic leukemia (T-ALL, n=12) and normal bone marrow donors (NBMD, n=35) were analyzed. A knowledge-based learning algorithm was generated by comparing the results of the minimal panel with the actual diagnosis, using discriminative function analysis. Correct classification of the test sample according to lineage, that is, BCP-ALL, T-ALL, AML and differentiation of NBMD was achieved in 97.2% of all cases with only six of the originally applied 13 mAbs of the panel. This provides evidence that discriminant function analysis can be utilized as a decision support system for interpretation of flow cytometry readouts.

A single-tube flow cytometric procedure for enhancing the diagnosis and prognostic classification of patients with myelodysplastic syndromes.

INTRODUCTION: We created a simple and effective flow cytometry scoring system (FCSS) for suspected Myelodysplastic syndromes (MDS) samples and evaluated its diagnostic and prognostic potential. METHODS: Besides evaluating the four parameters suggested by Ogata, we investigated erythroid precursors and mast cells. We evaluated the six-parameter FCSS in a four-color setting (test cohort: 51 patients; 25 controls), then we implemented it into an eight-color setting and tested it on a validation cohort of patients with MDS (n=31). RESULTS: When we compared MDS cases to non-MDS samples in the test cohort, we detected significant differences regarding not only the four major parameters but also two additional ones, namely CD71 rCV% of erythroid precursors (P=.004) and mast cell percentage (MC%) (P=.001). The utilization of the modified six-parameter FCSS provided high sensitivity and specificity both in the four color (84% and 80%, respectively) and in the eight color (81% and 100%, respectively) setting, with an excellent discriminative power between MDS and non-MDS samples. Furthermore, we found significant difference in event-free survival between the risk groups based on the modified six-parameter FCSS (P=.001). CONCLUSION: We evaluated and validated a single-tube flow cytometric procedure for a simple six-parameter FCSS which has not only high diagnostic but also prognostic power.

Leukemic lymphoblasts, a novel expression site of coagulation factor XIII subunit A.

Blood coagulation factor XIII (FXIII) is a protransglutaminase circulating as a tetramer formed by two types of subunits (A2B2). The intracellular dimeric form of FXIII (A2) is present in platelets, megakaryocytes, monocytes and macrophages and has been detected in mono- and megakaryocytic leukemias. The aim of our study was to investigate FXIII-A expression in newly diagnosed B cell acute lymphoblastic leukemia (ALL) samples. We examined 47 de novo ALL cases of B cell origin by triple color labeling with flow cytometry. FXIII-A was detected by a FITC conjugated monoclonal antibody combined with CD34 and CD45 staining. In selected cases FXIII-A was investigated on slides prepared from blasts and visualized with a fluorescent microscope. In addition, blasts were studied by Western blot analysis and FXIII-A was measured by a highly sensitive ELISA method. By flow cytometry 19 samples of the 47 cases were found to be FXIII-A positive. Antigen concentration was 3.11 +/- 1.19 fg/blast, while normal lymphoid precursors and mature lymphocytes from B-CLL did not contain FXIII-A. In the lysate of lymphoblasts that were positive by flow cytometry, a single band (82 kDa) corresponding to FXIII-A was detected on Western blots. Confocal laser scanning microscopic examination revealed the presence of FXIII-A in the cytoplasm of these lymphoblasts. This novel expression site of FXIII-A in leukemic lymphoblasts can be utilized as a diagnostic tool and may also gain functional significance in B-lineage ALL.

Platelet vinculin: a substrate of activated factor XIII.

In addition to plasma, Factor XIII of blood coagulation (FXIII) is also present in the cytosol of platelets, monocytes and macrophages. However, its intracellular function has not yet been revealed. Activated Factor XIII (FXIIIa) is a transglutaminase (protein-glutamine: amine gamma-glutamyltransferase, EC 2.3.2.13) of highly restricted substrate specificity with only a few known protein substrates. In this report, we showed that FXIIIa can link dansylcadaverine, radiolabelled histamine and putrescine to vinculin. Quantitative determinations revealed that in the vinculin molecule a single glutamine residue can serve as acyl donor for the incorporation of small-molecular-weight amines. Vinculin could not be crosslinked to another vinculin molecule. It could be covalently bound, however, to fibrinogen, which indicates that the acyl donor glutamine residue can be engaged in an epsilon-(gamma-glutamyl)lysyl crosslink formation. Since it has been shown that platelet actin and myosin, two main components of cytoskeleton, are also substrates for FXIIIa, and that vinculin is associated to the cytoskeleton during platelet activation, the involvement of FXIII in the stabilization of cytoskeleton at certain phases of cellular function is a likely possibility.

Factor XIII in bronchoalveolar lavage fluid from children with chronic bronchoalveolar inflammation.

BACKGROUND: Extravascular activation of the coagulation system and consequent fibrin deposition is involved in the pathomechanism of chronic bronchoalveolar inflammatory diseases. The turnover of extravascular fibrin is attenuated by its cross-linking with activated factor XIII (FXIII). OBJECTIVES: Determination of cellular and plasmatic forms of FXIII and their correlation with D-dimer level in the bronchoalveolar lavage fluid (BALF) from healthy children and from children with bronchoalveolar inflammation. PATIENTS AND METHODS: Highly sensitive immunoassays were used for the quantitation of cellular and plasma FXIII and D-dimer in the BALF of children with recurrent wheezy bronchitis and fibrosing alveolitis. BALF was investigated for FXIII-containing cells by flow cytometry. RESULTS AND CONCLUSIONS: In the BALF of controls a low amount of the cellular form of FXIII (FXIII A2) and D-dimer were measured, while plasma FXIII (FXIII A2B2) was absent. Alveolar macrophages represented the single cell population in BALF that contained FXIII. In the BALF of both patients' groups the concentration and the total amount of FXIII A2 was significantly elevated, and plasma FXIII also appeared in the BALF of most patients. The D-dimer concentration was also elevated in the patients' groups and it correlated both with plasma FXIII and neutrophil count. These findings suggest that FXIII A2 is released from activated or injured alveolar macrophages into the bronchoalveolar lining fluid and in bronchoalveolar inflammatory diseases, FXIII A2B2 also leaks out from the capillaries. By cross-linking fibrin and inhibitors of fibrinolysis to fibrin, FXIII might be a key regulator of fibrin turnover in the extravascular compartment.

Flow cytometric detection of intracellular myeloperoxidase, CD3 and CD79a. Interaction between monoclonal antibody clones, fluorochromes and sample preparation protocols.

Detection of intracellular myeloperoxidase (MPO), CD79a and CD3 has become the most specific tool for the assignment of myeloid, B- and T-lymphoid lineages in acute leukemias. In order to establish the best combination of monoclonal antibody reagent and sample preparation technique for the intracellular detection of these three markers, we compared six different cell fixation-permeabilization kits (Cytofix/Cytoperm, Fix and Perm, Intraprep, Intrastain, Permeacyte and Permeafix) using 12 fluorochrome conjugates derived from seven monoclonal antibody (mAb) clones. A total of 21 samples corresponding to normal peripheral blood (n=4), normal bone marrow (n=3), acute myeloblastic leukemia (AML, n=6), precursor B-acute lymphoblastic leukemia (ALL, n=6) and T-ALL (n=2) cases, were analysed in two centers. All fixation/permeabilization methods resulted in decreased side scatter and mostly increased forward scatter as compared to erythrocyte-lyse-washed and 1% paraformaldehyde fixed samples. The autofluorescence levels of the leukocyte populations was only significantly increased with use of the Cytofix/Cytoperm kit and mildly with the other techniques. In addition, non-specific staining increased significantly for combinations of any anti-MPO mAb with the Cytofix/Cytoperm kit and for the CD3 clone S4.1 combined with any intracellular method. Anti-MPO antibodies gave a stronger fluorescence signal when conjugated to PE than when coupled to FITC. In conclusion, MPO-7-PE, UCHT-1-PE (CD3) and any HM57-PE conjugate (CD79a) in combination with Fix and Perm, Intraprep, Intrastain or Permeafix, provided specific staining of the respective markers in sufficient intensities. Thus, combined selection of fixation/permeabilization kits and monoclonal antibody reagents against CD3, CD79a and MPO is required for obtaining optimal cytoplasmic detection of these antigens.

Characterization of monocyte-associated factor V.

We demonstrate that in addition to possessing binding sites for intact factor V (FV), unstimulated peripheral blood monocytes also express activated factor V (FVa) on their surfaces. FVa was identified on the monocyte surface by monoclonal antibody B38 recognizing FVa light chain and by human oligoclonal antibodies H1 (to FVa light chain) and H2 (to FVa heavy chain) using immunofluorescence microscopy and flow cytometry. On Western blots, partially cleaved FV could be identified as a 220 kDa band in lysates of monocytes. In addition to surface expression of FVa, monocytes also contain intracellular FV as detected only after permeabilization by Triton X-100 by monoclonal antibody B10 directed specifically to the Cl domain not present in FVa. We sought to determine whether the presence of FV in peripheral blood monocytes is a result of de novo synthesis. Using in situ hybridization, no FV mRNA could be detected in monocytes, while in parallel control studies, factor V mRNA was detectable in Hep G2 cells and CD18 mRNA in monocytes. In addition, using reverse transcriptase and the polymerase chain reaction, no FV mRNA was detected in mononuclear cells or in U937 cells, but mRNA for factor V was present in Hep G2 cells using the same techniques. These data suggest that FV is present in human monocytes, presumably acquired by binding of plasma FV, and that the presence of this critical coagulation factor is not due to de novo synthesis.

Factors of the extrinsic pathway of blood coagulation in tumour associated macrophages.

Despite the growing evidence implicating intratumoural fibrin formation in the progression of malignant tumours, the origin of coagulation factors that participate in extravascular clotting has not been elucidated. Using immunohistochemical methods we attempted to detect and localize clotting factors of extrinsic pathway in different human malignant tumours. Coagulation factors II, V, VII and X (FII, FV, FVII and FX) were detected in a huge number of cells showing spindle-shaped or stellate morphology. By double immunohistochemical labellings it was demonstrated that cells containing these clotting factors express monocyte/macrophage differentiation marker antigens recognized by Leu M3, Ki M7 and DAKO-macrophage monoclonal antibodies, i.e. they represent monocyte-derived, phagocytic tumour associated macrophages (TAMs). These findings suggest that TAMs can be viewed as clot cells, which in addition to the initiation of extravascular clotting by expressing procoagulant activity can also provide all the components necessary for the extrinsic thrombin formation.

Onset and distribution of factor XIII-containing cells in the mesenchyme of chorionic villi during early phase of human placentation.

To learn more about the distribution and possible function of factor XIII (FXIII)-containing cells of human placenta, paraffin embedded and frozen sections of placenta samples from the first trimester of pregnancies--terminated by legal abortions--were studied by single and double labelling immunomorphological techniques. It was observed that at the fifth gestational week in the chorionic mesenchyme, FXIII-containing small mononuclear, round shaped cells start to appear. The relative amount of the FXIII-containing cells rapidly increased up to the seventh gestational week, reaching nearly 30 per cent of all mesenchymal cells. Simultaneously these cells differentiated into large stellate cells having numerous vacuoles in their cytoplasm. These cells were characterized in double labelling experiments and proved to be macrophages (CD 14+, KiM7+, labelled with antimacrophage monoclonal antibody). In the fifth-seventh weeks of gestation, these cells were homogenously scattered in the immature mesenchymal connective tissue, but from the eight gestational week they tended to accumulate in the peripheral part of chorionic villi while the central mesenchyme showed intense fibrotic changes. The abundance and characteristic distribution of the FXIII-positive macrophages in the chorionic mesenchyme during the first trimester of pregnancy suggest that these cells may have an active role in the formation of connective tissue in the early phase of placentation.

Effect of myelopoietic and pleiotropic cytokines on colony formation by blast cells of children with acute lymphoblastic leukemia.

The aim of this study was to see whether pleiotropic or myeloid hematopoietic growth factors, which do not stimulate normal lymphoid cells, can induce proliferation of blast cells of the acute lymphoid leukemia (ALL) of childhood. Bone marrow cells of 13 children with untreated ALL (nine common ALL, two myeloid antigen positive ALL and two early T-cell ALL) formed colonies of leukemic blast cells in primary methylcellulose cultures. Spontaneous growth was observed in three of 13 cases, whereas phytohemagglutinin-stimulated leukocyte conditioned medium (PHA-LCM), a conventional source of various natural human cytokines, induced colony formation in ten of 13 cases. A similar rate of responsiveness was seen with recombinant human granulocyte colony-stimulating factor (G-CSF), granulocyte-macrophage colony-stimulating factor (GM-CSF) and stem cell factor (SCF); a combination of these three cytokines induced colony formation in all cases studied. The effect of these growth factors on colony formation seemed to be dose-dependent in some cases. Of the stimuli studied, GM-CSF induced the smallest number of colonies, whereas the effects of G-CSF, SCF and PHA-LCM were similar in this respect. Combination of cytokines proved to be even more efficient in inducing clonal proliferation of leukemic lymphoblasts. In double combinations, G-CSF and GM-CSF as well as G-CSF and SCF were able to potentiate each other's effects. Triple combination of these cytokines mediated the most potent growth stimulus. Our results demonstrate that myeloid and pleiotropic cytokines are able to stimulate clonal proliferation of pediatric leukemic lymphoblasts. This may present a potential hazard to children with ALL while on adjuvant therapy with hematopoietic growth factors. In vitro colony assays performed prior to or in parallel with the administration of hematopoietic growth factors to ALL patients may help to forecast their possible effects on leukemic cells in vivo.

Cerebrovascular reactivity and reserve capacity in type II diabetes mellitus.

The aim of the study was to test the hypothesis that cerebrovascular reserve capacity and cerebrovascular reactivity are impaired in patients suffering from non insulin-dependent diabetes mellitus. We also intended to investigate factors which may influence resting cerebral blood flow velocity and cerebrovascular reserve capacity. A total of 28 patients suffering from type II diabetes mellitus and 20 healthy control subjects were studied. Based on diabetes duration patients were divided into two groups: subjects with > 10 years and those with < or = 10 years disease duration. Middle cerebral artery mean blood flow velocities were measured at rest and after intravenous administration of 1g acetazolamide. Cerebrovascular reactivity and reserve capacity were calculated. Blood glucose, insulin, glycosylated hemoglobin, hemostatic factors (fibrinogen, alpha-2 macroglobulin and von Willebrand factor antigen) were determined. Cerebrovascular reactivity and reserve capacity values were compared between the two diabetic subgroups and controls. Correlations between laboratory parameters and cerebrovascular reserve were investigated by linear regression analysis. Resting cerebral blood flow velocity was similar in controls and in the two diabetic subgroups. Cerebrovascular reactivity was elevated for a shorter time in patients with > 10 years disease duration than in controls and short-term diabetic patients. Cerebrovascular reserve capacity was lower in the long-term diabetes group (means +/- SD: 39.6 +/- 20.7%) than in patients with < or = 10 years disease duration (63.3 +/- 17.4%, p < 0.02 after Bonferroni correction). Cerebrovascular reserve capacity was inversely related to the duration of the disease (R = 0.53, p < 0.003). None of the determined laboratory factors had any relation with resting cerebral blood flow and cerebrovascular reserve capacity. The vasodilatory ability of cerebral arterioles is diminished in long-standing type II diabetes mellitus.

Membranous glomerulonephritis in a patient with inherited activated protein C resistance.

We present a patient with membranous glomerulonephritis, several clinical complications of the antiphospholipid syndrome and ulcerative colitis, but without lupus anticoagulant and antiphospholipid/cofactor antibodies. Immunological studies--other antibodies--were negative and failed to show enough criteria for any autoimmune diseases. Evaluation of her laboratory tests for hereditary thrombophilia revealed a heterozygous form of the Leiden mutation that might be associated with widespread vasculopathy. An interesting possibility is that the inherited activated protein C resistance could be an additional risk factor for vaso-occlusive manifestations appearing as a clinical sign of cardiovascular diseases and nephropathy.

Evaluation of hemostatic changes and blood antioxidant capacity in acute and chronic pancreatitis.

BACKGROUND/AIMS: We examined changes in hemostasis, in levels of total antioxidant capacity, and pancreatic enzymes (amylase, lipase) in patients with pancreatitis 1, 3 and 7 days after admission to the clinic, in order to evaluate the inflammatory processes in acute and chronic pancreatitis and to identify new prognostic markers. METHODOLOGY: The rate of CD62 expression--a marker of platelet hyperactivity--and the rate of platelet-leukocyte aggregates were measured by flow cytometry. The connection between the parameters measured and the severity of pancreatitis and also the differences of the parameters in acute and chronic pancreatitis were investigated. RESULTS: On the basis of previous studies it was assumed, that there is a connection between the level of parameters measured and the inflammatory process in the pancreas, and also between the defending processes of the body against free radicals. CONCLUSIONS: Based on our results, we suggest to extend the laboratory measurements to the investigation of hemostatic parameters. The measurement of plasma level of fibrinogen, von Willebrand factor and the rate of platelet activation is especially important.

[Hairy cell leukemia: authors' own experience (1977-1998)]. / A "hajas" sejtes leukaemiáról: saját tapasztalatok (1977-1998).

Hairy cell leukaemia (HCL) is a rare, clinically and haematologically well characterised entity. The prognosis of patients with hairy cell leukaemia has significantly improved due to the new therapeutic approaches. Development of diagnostic and therapeutic methods, together with the analysis of their own hairy cell leukaemia patients, is reviewed by the authors. Between 1977 and 1998 twenty five patients (16 male, 9 female) were treated. The malignant cells were usually analysed by morphological and cytochemical methods and recently flow cytometric analysis could be performed in eight patients. Splenectomy with lethal outcome in six patients was performed in 21 cases. Approximately one third of patients received interferon, while 2-chlorodeoxyadenosine was given only to three patients. Favourable experiences obtained by splenectomy and efficacy of interferon treatment are emphasised, but according to the literature and their own results administration of purine analogues can be highly recommended in the future.

[Molecular biology examination in chronic lymphocytic leukemia]. / Molekuláris biológiai vizsgálatok krónikus lymphoid leukaemiában.

Chronic lymphocytic leukaemia (CLL) is the most common adult leukaemia characterised by the accumulation of monoclonal CD5 + B-lymphocytes. The pathogenesis and the biology of CLL is complex and many details are still unknown. Several molecular biological methods have been used in the investigation of CLL, among them the study of apoptosis appears to be one of the most important. Initial experiences obtained by the spontaneous and fludarabine induced apoptosis, multidrug resistance (MDR)-test and fluorescent in situ hybridization (FISH) are reported by the authors. Apoptosis of CLL cells could be induced by fludarabine, while more studies should be performed to determine the exact role of MDR-test and FISH.

[Hemostatic abnormalities in ischemic stroke]. / Haemostasis eltérések ischaemiás stroke-ban.

The authors studied whether haemostatic abnormalities connected with the development of cerebral circulatory disturbances can be demonstrated in young stroke patients in whom Doppler and angiographic examination failed to reveal deviations indicative of stroke. They determined the in vivo activation of the coagulation system (TAT, F 1 + 2), the degree of secondary fibrinolysis (D-dimer), the plasma levels of the markers of fibrinolysis, with special regard to inhibitors: plasminogen activator inhibitor (PAI-1), alpha 2 antiplasmin (alpha 2 AP), alpha 2 macroglobulin (alpha 2 M), the frequency of pathologic serum lipoprotein (a)-Lp(a)-values and the association of PAI-1 and Lp(a) with the fibrinolytic system. They conclude that in the acute phase of the disease, the TAT and F 1 + 2 values were significantly elevated compared to the control, without change in the D-dimer value. The results suggest that in the tested period increased thrombin generation dominated and it significantly surpassed plasmin activity since the D-dimer values of that period did not indicate substantial increase in secondary fibrinolysis. The results of the study were separately analyzed in acute, chronic TIA and stroke groups. In the TIA and acute group the F 1 + 2 values, while in stroke the TAT values were more elevated. The in vitro fibrinolytic capacity of the patients significantly decreased compared to controls, showing significant correlation with the Lp(a) level, but not with the PAI value. Examination of the marker molecules renders possible to assess the degree of hypercoaguability and of endogenous lysis. Their knowledge is held important for judging the progression of the disease and the therapeutic consequences.