PubMed Health⌕ Search

Biomedical subjects

Krzysztof Lewandowski

Publications and source records attributed to Krzysztof Lewandowski.

At least 19 recordsLinked to original sources

Genetic background of Richter transformation of atypical chronic lymphocytic leukemia to diffuse large B-cell lymphoma - a case study.

Atypical chronic lymphocytic leukemia (aCLL) is an indolent lymphoproliferative neoplasm derived from CD19-positive and CD5 or CD23-negative B cells. This paper presents the results of whole genome sequencing (WGS) of lymphoma cells collected from a 29-year-old woman initially diagnosed with aCLL and successfully treated with fludarabine, cyclophosphamide, and rituximab. Eight years later, due to disease progression, she was treated with ibrutinib. After 5 months, her status suddenly deteriorated. PET-CT results suggested Richter transformation (RT). Histopathological examination of nodal lesions confirmed the diagnosis of Diffuse Large B Cell Lymphoma (DLBCL). Finally, the patient was successfully treated with DHAP-R and alloHSCT. WGS of lymphoma cells revealed the presence of pathogenic (COL11A1, MGME1) and likely pathogenic variants (ZMYM3, ALG6, UBA5, and ATG7). Out of these genes, only ZMYM3 is recurrently mutated in B-cell chronic lymphocytic leukemia (B-CLL). The presence of the other lesions requires further studies and indicates the complex molecular background of aCLL transformation to DLBCL. Therefore, the whole-genome variant assessment is worth considering for introduction into a routine procedure at the time of B-CLL diagnosis, especially when RT is suspected.

Humans↗

Cladribine in a weekly versus daily schedule for untreated active hairy cell leukemia: final report from the Polish Adult Leukemia Group (PALG) of a prospective, randomized, multicenter trial.

Cladribine (2-chlorodeoxyadenosine, 2-CdA) treatment-associated infections may shorten potentially long-term survival in hairy cell leukemia (HCL). In search of the optimal mode of 2-CdA administration, 132 patients with untreated HCL were randomized to receive either standard 5-day 2-CdA protocol or a novel schedule of 6 weekly 2-CdA infusions suggested to be less toxic. Analysis of treatment response confirmed similar complete remission rates, overall response rates, progression-free survival, and overall survival in both 2-CdA protocols. However, we did not observe lower toxicity in the weekly schedule. Of special interest, no significant differences were found in the rate of grade 3/4 infections (18% for daily and 26% for weekly protocol, difference -8.2%; 95% confidence interval [CI] -23.2% to 6.9%; P = .28) and the rate of septic deaths (3% for daily and 2% for weekly protocol, difference 1.4%; 95% CI -4.3% to 7.0%; P = .64). In conclusion, HCL treatment with weekly 2-CdA infusions is equally effective but no safer than the standard 5-day 2-CdA protocol.

Adult↗

Fludarabine, cytarabine, and mitoxantrone (FLAM) for the treatment of relapsed and refractory adult acute lymphoblastic leukemia. A phase study by the Polish Adult Leukemia Group (PALG).

Outcome of adults with acute lymphoblastic leukemia (ALL) who fail to achieve complete remission (CR) or who relapse soon after initial response is poor. The goal of this phase II study by the Polish Adult Leukemia Group (PALG) was to evaluate safety and efficacy of a new salvage regimen (FLAM) consisting of sequential fludarabine, cytarabine, and mitoxantrone. Fifty patients were included with primary (n = 13) or secondary (n = 5) refractoriness, early (<12 months) first relapse (n = 15), first relapse after hematopoietic cell transplantation (HCT) regardless CR duration (n = 13), and second or subsequent relapse (n = 4). Median age was 31(18-60) years, 28% of patients were bcr/abl-positive. CR rate equaled 50% and was significantly higher for patients in whom FLAM was administered as a second-line therapy compared to those more heavily pre-treated (66 vs 13%, p = 0.02). Seventeen patients had leukemia regrowth after initial cytoreduction, whereas, eight patients died in aplasia. The incidence of early death was higher in patients aged > or =40 years compared to the younger subgroup (33 vs 8%, p=0.03). Septic infections were the most frequent severe complication. At 3 years, the probability of disease-free survival for patients who achieved CR equaled 16%. Seven patients underwent allogeneic HCT. FLAM regimen is feasible for relapsed and refractory adults with ALL and could be recommended in particular for younger patients as a second-line treatment. However, as the remission duration is short, allogeneic HCT (alloHCT) should be considered as soon as possible.

Adolescent↗

Amplification of hTERT and hTERC genes in leukemic cells with high expression and activity of telomerase.

Reactivation of telomerase plays an important role in carcinogenesis. Malignant cells almost always possess high activity and expression of telomerase. The aim of this study was to see whether there is any relationship between telomerase activity and expression and hTERT and hTERC gene amplification in acute lymphoblastic leukemia (ALL) and non-lymphoblastic leukemia (ANLL) cells. In addition telomere length was tested in leukemic cells at the time of diagnosis and during remission. Expression of the three components of telomerase (hTERT, hTERC and TP1) as well as telomerase activity was found both in ALL and ANLL cells. Telomerase activity was diminished in patients in remission. The leukemic cells showed considerable heterogeneity of terminal restriction fragments, that is telomere length. ALL cells showed a variable pattern of telomere length in contrast to ANLL cells which produced a predominantly short telomere pattern. Telomere length in the lymphocytes of leukemia patients was shorter in remission as compared to the time of diagnosis. FISH analysis revealed amplification of hTERT and hTERC genes in ALL and ANLL cells. Quantitative analysis showed that leukemic cells possess higher number of hTERT and hTERC copies than the normal PBL. Our results suggest that the activation of telomerase in leukemic cells is connected with amplification of hTERT and hTERC genes. The high expression and activity of telomerase found in leukemic cells may be partially explained by amplified hTERT and hTERC genes. Amplification of the telomerase genes seems to be a common event in carcinogenesis and may play a role in telomerase reactivation leading to cell immortalization.

DNA-Binding Proteins↗

Comparison of cladribine plus prednisone with chlorambucil plus prednisone in patients with chronic lymphocytic leukemia. Final report of the Polish Adult Leukemia Group (PALG CLL1).

BACKGROUND: We previously published an early report of a randomized, multicenter trial on the efficacy and toxicity of cladribine (2-CdA) + prednisone (P) compared with chlorambucil (Chl) + P in previously untreated patients with progressive or symptomatic chronic lymphocytic leukemia. Here we present the final report of this study. MATERIAL/METHODS: Of 229 patients, 126 received 2-CdA+P and 103 Chl+P. Patients with no response or progression after three courses or who relapsed earlier than 12 months after completing one treatment were switched to the other. Patients who relapsed later were retreated with the same schedule as before. RESULTS: Thirty-three patients were retreated with 2-CdA+P and 19 with Chl+P. Overall response (and complete response) rates were 35% (6%) and 47% (16%), respectively. In 50 patients initially treated with Chl+P and then with 2-CdA+P, complete response (CR) was achieved in 12 (24%) and overall response (OR) in 32 (64%). In 28 patients originally treated with 2-CdA+P and then with Chl+P, CR in 1 (3%, p=0.01) and OR in 6 (21%, p=0.003) were obtained. We found no statistically significant difference in overall survival time in patients treated initially with 2-CdA+P and Chl+P aged 60 years (4.63 and 5.27 years, respectively, p=0.45), 60-70 years (3.29 and 3.14 years, p=0.79), and >70 years (1.53 and 1.93 years, p=0.11). CONCLUSIONS: 2-CdA+P is significantly more effective as a second-line treatment and re-treatment than Chl+P. However, we found a trend to longer survival in elderly patients treated with Chl+P.

Aged↗

Cancer procoagulant in patients with adenocarcinomas.

Cancer procoagulant (CP) is a cysteine proteinase that may be produced by malignant and foetal tissue. The possible role of CP in the pathogenesis of cancer-related thrombosis has been suggested recently. The purpose of the study was to evaluate coagulation prothrombotic markers and their relation to CP concentration in the blood of patients with gastrointestinal adenocarcinomas (GIAC). The study group consisted of 45 patients with confirmed diagnosis of adenocarcinoma (stomach, 18 patients; colon, 27 patients) and without evident metastatic disease. In 24 patients further observation showed metastases. The control group for CP was composed of 10 healthy subjects. Blood samples were drawn on the admission day, before any treatment. Among 45 patients with GIAC, deep venous thrombosis was observed in two (4.4%). In all patients the CP activity in the serum was found, and the mean CP activity shortened the coagulation time almost three times compared with the healthy control group. Also, the mean thrombin-antithrombin complex concentration was above the normal range. A significant elevation of the mean prothrombin fragment 1+2 plasma content in this group of patients was noticed. Despite these observations, CP remained within the normal range and did not correlate with thrombin-antithrombin complex or prothrombin fragment 1+2 plasma concentrations. A positive correlation was observed between serum CP and fibrinogen concentration, and a negative correlation between CP and free protein S plasma content (P = 0.04 and P = 0.025, respectively). A negative correlation between activated protein C resistance ratio and protein C activity in the plasma was confirmed. Protein C activity in the plasma showed a correlation with free protein S plasma content. Analysis of factors influencing the activated partial thromboplastin time revealed the presence of antiphospholipid antibodies in seven persons from the study group (in three cases of IgG and in four cases of IgM class). Our data suggest that CP is a minor risk factor for deep venous thrombosis in GIAC patients. To confirm this, however, the number of patients and controls should be larger. After 3 years of observation, the follow-up in 10 living GIAC patients showed nobody with thromboembolic disease.

Adenocarcinoma↗

The prevalence of C807T mutation of glycoprotein Ia gene among young male survivors of myocardial infarction: a relation with coronary angiography results.

INTRODUCTION: The glycoprotein complex Ia/IIa (GP Ia/IIa) is a major collagen receptor on platelets and other cell types. Recently, linked polymorphisms within the coding region of the GP Ia gene (C807T and G873A) related to GP Ia/IIa surface expression have been identified. The 807T/873A allele is associated with high expression, whereas the 807C/873G allele is associated with low surface expression of GP Ia/IIa. Subsequently, the 807T allele was found to be associated with coronary artery disease (CAD) and cerebral infarction in younger patients. Moreover, platelet thrombus formation is significantly influenced by genetic variations of the GPIb alpha and GPIa receptors and is dependent on the blood flow rate. AIM: 1. To determine the frequency of C807T polymorphism of the GPIa gene in young survivors of myocardial infarction (MI) and 2. to evaluate the relationship between the intensity of CAD in the coronary angiography examination and the 807C/T genetic status of the patients. METHODS: 102 young male survivors of MI (YSMI) -- mean age 43, range 29-49 years, mean age at the time of the first episode 37+/-3 years -- were studied. Obesity was found in 15%, diabetes in 14%, hyperlipidemia in 87%, hypertension in 22% and smoking history in 90% of cases. Familial CAD and/or MI were confirmed in 50% of patients. The control group consisted of 106 healthy volunteers with a negative family history of CAD, both medical staff members and blood donors (mean age 40, range 18-42 years). The genetic study was performed using genomic DNA obtained from peripheral blood leukocytes. The C807T polymorphism of platelet glycoprotein Ia (GPIa) was investigated using the PCR method introduced by Santoso et al. RESULTS: Coronary angiography (Siemens Bicor system) revealed single-artery disease in 34%, two-artery disease in 36% and three-artery disease in 26% of patients. In two patients there were no signs of CAD. The C807T polymorphism of GPIa was found in 73.5% of investigated patients (heterozygotes CT 59.8%, homozygotes TT 13.7%). The CC genotype was confirmed in 26.5% of patients. A similar analysis performed in the group of healthy men showed C807T polymorphism of the GPIa gene in 73.6% (CT in 58.5% and TT in 15.1% of persons, ns). CC genotype was found in 26.4% of persons. Interestingly, the T genotype frequency was similar in patients with three- or two-artery disease in comparison with patients with single-vessel or without CAD (49.3% vs. 50.7%, respectively, ns). In 75 YSMI carrying C807T polymorphism of the GPIa gene additional genetic abnormalities were confirmed in 21 patients - BclI polymorphism of b-chain fibrinogen gene, G4070A and G1691A (FV Leiden) mutation of factor V gene and C677T polymorphism of methylenetetrahydrofolate reductase gene. Partial occurrence of combined polymorphisms was found. This was confirmed independently of the number of coronary arteries involved. CONCLUSIONS: Our results may question the potential role of C807T the GPIa anomaly as a single genetic abnormality predisposing young men to coronary artery disease.

Adult↗

[The role of thrombin activatable fibrinolysis inhibitor in disturbances of fibrinolytic system in obesity].

The aim of the study was to evaluate fibrinolysis in obese women. Study group consisted of 45 obese women (mean age 36,8 +/- 16,6 years, mean BMI 35,7 +/- 4,9), who were allocated to two subgroups: premenopausal (mean age 32,3 +/- 9,9 years, mean BMI 36,9 +/- 5,6) and postmenopausal (mean age 64,8+/-10,1 years, mean BMI 33,3 +/- 2,55). Control group consisted of 45 women (mean age 35,3 +/- 13,9 years) with normal BMI (21,8 +/- 3,09). Global fibrinolytic activity was diminished only in obese women after menopause. Final analysis revealed significant increase of TAFI antigen and activity in the plasma of obese women. The existence of significant correlation in multifactor regression analysis between TAFI plasma content and euglobulin clot lysis time (ECLT) and global fibrinolytic capacity (GFC) as well confirmed negative influence of this inhibitor on fibrinolytic capacity in obese women. The increase of TAFI antigen and activity in the plasma was independent of age, BMI, glucose, cholesterol, triglicerides, insulin and leptin concentration in the plasma. The results of ECLT and GFC may be also influenced by PAI-1 activity particularly in women before menopause, which was significantly elevated in our group of patients. This increase as not dependent with TAFI antigen concentration. In conclusion, the observed increase TAFI antigen and activity in the plasma of obese women may influence the thrombotic risk in this group of patients, especially after menopause.

Adult↗

[Systemic mastocytosis].

Mastocytosis is group of rare disorders characterized by abnormal mast cells growth. Pathology of the disease is unknown, mechanisms involved in mast cells delineation and growth are considered to play an important role. Unusual and broad spectrum of symptoms therefore requires cooperation of different specialists. The aim of the study was to assess diagnostic and therapeutic methods used in the Gdansk Mastocytosis Centre. 14 patients were studied (9 adults and 5 children). Bone marrow biopsy was performed in order to assess the stage of disease. Pathological, cytological, cytofotometry and genetic examination (C-KIT mutation) of the bone marrow were performed. Patients suffereing from food allergy and wasp venom anaphylaxis were diagnosed with skin prick tests and sIgE. All subjects suffered from urticaria pigmenthosa and anaphylaxis. Indolent mastocytosis was diagnosed in six subjects. Patients were treated with antihistamines, corticosteroids, cromones and immunotherapy with a marked reduction of symptoms. The experience of Gdansk Mastocytosis Centre indicates that mastocytosis is a rare and difficult to diagnose disease.

Adult↗

Evaluation and comparison of random amplification of polymorphic DNA, pulsed-field gel electrophoresis and ADSRRS-fingerprinting for typing Serratia marcescens outbreaks.

Amplification of DNA fragments surrounding rare restriction sites (ADSRRS-fingerprinting) is a novel assay based on suppression of polymerase chain reaction (PCR). This phenomenon allows the amplification of only a limited subset of DNA fragments, since only those with two different oligonucleotides ligated at the ends of complementary DNA strands are amplified in the PCR. The DNA fragments can be easily analyzed on polyacrylamide gels, stained with ethidium bromide. We have implemented this method using a set of clinical Serratia marcescens isolates from three outbreaks ongoing in the Public Hospital in Gdańsk (Poland). Clustering of ADSRRS-fingerprinting data matched epidemiological, microbiological, random amplification of polymorphic DNA (RAPD) and pulsed-field gel electrophoresis (PFGE) data. Based on this study, we found that there is at least a similar power of discrimination between the present 'gold-standard' PFGE and the novel method, ADSRRS-fingerprinting. Although the ADSRRS-fingerprinting method may appear to be more complex than the RAPD technique, we found it fast and reproducible.

Anti-Bacterial Agents↗

Evaluation of a novel method based on amplification of DNA fragments surrounding rare restriction sites (ADSRRS fingerprinting) for typing strains of vancomycin-resistant Enterococcus faecium.

In the search for an effective DNA-typing technique for use in hospital epidemiology, the performance and convenience of a novel assay based on the fingerprinting of bacterial genomes by amplification of DNA fragments surrounding rare restriction sites (ADSRRS fingerprinting) was tested. A large number of vancomycin-resistant Enterococcus faecium (VREM) isolates from haematological ward patients of the Clinical Hospital in Gdańsk were examined. We found that ADSRRS fingerprinting analysis is a rapid method that offers good discriminatory power. The method demonstrated also excellent reproducibility. The usefulness of the ADSRRS fingerprinting method for molecular typing was compared with pulsed field gel electrophoresis (PFGE) method, which is currently considered the gold standard for molecular typing of isolates recovered from patients and the environment in the course of investigation and control of nosocomial outbreaks. Clustering of ADSRRS fingerprinting data matched pulsed field gel electrophoresis data. The features of ADSRRS fingerprinting technique is discussed in comparison with conventional methods. Data presented here demonstrate the complexity of the epidemiological situation concerning VREM that may occur in a single medical ward.

Bacterial Proteins↗

Multiple sclerosis-associated virus-related pol sequences found both in multiple sclerosis and healthy donors are more frequently expressed in multiple sclerosis patients.

In the etiopathogenesis of multiple sclerosis (MS), both genetic and environmental factors play an important role. Among environmental factors, viral infections are most likely connected with the etiology of MS. There are many evidence suggesting possible involvement of retroviruses in the development of autoimmune diseases including MS. Multiple sclerosis-associated retrovirus (MSRV) seems to be the important candidate for viral etiology of MS. The aim of the study was to analyze MSRV pol sequences in patients with MS. As control, groups of myasthenia gravis, Parkinson's disease, and migraine patients, and healthy individuals have been studied. The MSRV pol sequences have been analyzed in RNA isolated from the serum and in DNA and RNA of peripheral blood lymphocytes from untreated MS patients and control groups. The MSRV pol sequences have been detected by reverse transcriptase-polymerase chain reaction (RT-PCR) and PCR technique, using specific oligonucleotide primers. In the serum RNA (cDNA), MSRV pol sequences have been identified in 31/32 MS patients. MSRV pol sequences were detected in serum cDNA of 9/17 myasthenia gravis patients, 7/16 Parkinson's disease patients, 10/21 migraine patients, and 13/27 healthy individuals. MSRV pol sequences were observed also in RNA from lymphocytes of all MS patients, 12/17 myasthenia gravis patients, 9/16 Parkinson's disease patients, 14/21 migraine patients, and 18/27 healthy donors. In the DNA from peripheral blood lymphocytes of all studied patients and healthy individuals, MSRV pol sequences have been found. The observed pattern of fiber-fluorescence in situ hybridization (FISH) signals suggests the presence of multiple copies of MSRV pol sequences, most likely tandemly dispersed in the genome. It can be concluded that MSRV pol sequences are endogenous, widespread in lymphocytes DNA, and transcribed into RNA of MS patients as well as of other studied patients and healthy individuals. However, more frequent expression of MSRV sequences detected in lymphocytes RNA (cDNA), as well as their presence in higher frequency in the serum of MS patients, may suggest the involvement of MSRV in the etiopathogenesis on MS.

Adult↗

Activity and expression of human telomerase in normal and malignant cells in gastric and colon cancer patients.

BACKGROUND: The reactivation of telomerase is believed to play an important role in immortalization and carcinogenesis. OBJECTIVE: To investigate the expression of three components of the telomerase complex (hTR, hTERT and TP1), along with telomerase activity in malignant and normal cells. METHODS: Cells were isolated from gastric and colon cancer, and from normal mucosa from the stomach and colon of participating patients. Expression of hTERT, hTR and TP1 has been studied by the reverse transcriptase polymerase chain reaction (PCR) technique. The telomerase repeat amplification protocol and PCR enzyme-linked immunosorbent assay were used for analysis of telomerase activity. RESULTS: All telomerase components were consistently expressed in colon and gastric cancer cells. Neoplastic RNA produced consistently very strong amplification signals either for hTR, hTERT or TP1. The expression of hTR was observed in RNA isolated from all normal mucosa samples and from peripheral blood lymphocytes. The expression of TP1 and hTERT has been found in the majority of normal cells; however, the amplification signals produced were usually much weaker than in malignant cells. The limiting dilution experiments indicated that the cancer cells have at least 100-fold higher telomerase activity and at least 25-fold higher TP1 and hTERT expression in comparison to normal cells. CONCLUSIONS: It can be concluded that all the cancer cells tested have higher telomerase expression and activity than normal cells. Therefore, telomerase can be a good cancer marker, provided that quantitative analysis is carried out.

Carrier Proteins↗

[Successful pregnancy outcome in the woman with thrombophilia and multiple miscarriages].

OBJECTIVES: The case of a 25 year-old pregnant woman with a history of miscarriage (8 week) and a triple intrauterine fetal death (35, 25, 21 week) was reported. RESULTS: Personal and family history did not revealed any abnormalities. In the 25th week of gestation routine ultrasonographic examination showed abnormal pulsation indexes in the umbilical artery, as well as the right and left uterine artery. Also extremely high vascular resistance was confirmed in both uterine arteries (notch). The routine laboratory tests were normal. Because of high risks of stillbirth and preliminary pregnancy termination the screening tests for thrombophilia were performed. The presence of a heterozygous form of factor V Leiden mutation and C677T polymorphism of a methylenetetrahydrofolate reductase gene were confirmed. The low doses of LMWH (nadroparine) subcutaneously and aspirin (150 mg per day, orally) were administered until pregnancy termination. In the 35th week of gestation the pregnancy was terminated by cesarean section due to fetus intrauterine asphyxia (boy 1180 g, Apgar 1 min-6, Agar 5 min 9 points). Three months' follow-up after delivery did not revealed any complication in the mother or in the child. CONCLUSIONS: Successful pregnancy outcome in the woman with thrombophilia and multiple miscarriages confirms the necessity for both prophylactic anticoagulant treatment and detailed laboratory testing.

Abortion, Habitual↗

Lack of correlation between telomere length and telomerase activity and expression in leukemic cells.

The expression of three components of telomerase complex (hTR, hTERT, TP1) along with telomerase activity and telomere length in leukemic cells was investigated. Cells were isolated from peripheral blood and/or bone marrow of children with acute lymphoblastic (ALL) and non-lymphoblastic (ANLL) leukemia. Expression of three components of telomerase as well as telomerase activity was found in all leukemic cells. Chemiluminescent detection of terminal restriction fragments (TRF) from DNA isolated from ALL cells showed variable patterns expressing considerable heterogeneity of telomere length. The ALL cells appeared to have both long and short telomere lengths, in contrast to normal peripheral lymphocytes, which produced limited pattern of TRF. The ANLL cells produced predominantly short telomere pattern despite high telomerase activity and expression. It can be concluded that high telomerase activity and expression in leukemic cells is not always correlated with long telomeres (TRF pattern).

Chromosome Mapping↗

Myocardial infarction in patients aged less than 40 years. Frequency of BclI polymorphism in the fibrinogen beta-chain gene and plasma fibrinogen.

BACKGROUND: Several polymorphisms in the genes encoding for three separate chains of fibrinogen have been described. Some of them (Hae III and B854) are associated with elevated fibrinogen plasma level. AIM: To determine the frequency of BclI polymorphism in the fibrinogen beta-chain gene (BclI betaFb) in young survivors of myocardial infraction (MI) and to assess the relationship between allele status, plasma fibrinogen concentration and the number of affected coronary arteries. METHODS: The study group consisted of 99 male patients (mean age 43.5, range 29-49 years) with premature coronary artery disease (CAD) diagnosed by coronary angiography who had MI in the mean age of 37.4+/-3.2 years. The control group involved 78 age- and gender-matched healthy volunteers. DNA was extracted from peripheral blood leukocytes using standard methods. Fibrinogen blood concentration was determined using biuretic method. The BclI polymorphism in the fibrinogen beta-chain gene was investigated using polymerase chain reaction (PCR). RESULTS: Obesity was found in 15%, smoking - in 89%, hypertension - in 21%, diabetes - in 14% and hyperlipidemia - in 86% of MI patients. A family history of MI was present in 50% of patients. Coronary angiography revealed single-vessel disease in 34%, two-vessel disease in 36%, and three-vessel disease in 16% of patients. In two patients coronary angiography was normal. The frequency of BclI polymorphism of the beta-fibrinogen gene was significantly higher in MI patients than in controls (40.4% vs 29.5%, p<0.01). Moreover, in MI patients carrying the mutant allele a higher concentration of blood fibrinogen was found in comparison to patients without this anomaly (3.87 vs 3.55 g/L, p=0.05). There was no evidence of an association between the number of affected coronary arteries and polymorphism of BclI betaFbg gene status. However, all patients carrying BclI polymorphism of betaFbg gene had abnormal coronary angiography, contrary to patients without any defect. CONCLUSIONS: 1. Polymorphism of BclI betaFbg gene is associated with an increased fibrinogen plasma level. 2. There is no association between BclI polymorphism of betaFbg gene and the number of affected coronary arteries. This may confirm the hypothesis of multi-factorial aetiology of CAD in young patients suffering MI.

Adult↗

Modulation of the activity of calcium-activated neutral proteases (calpains) in chronic lymphocytic leukemia (B-CLL) cells.

Decreased susceptibility to apoptosis and impaired proliferative control are thought to be responsible for prolonged life span and accumulation of chronic lymphocytic leukemia (B-CLL) cells. The activity of calpains (calcium-dependent, neutral proteases, active in the cells responding to signals inducing a rise of cytoplasmic Ca(++)) is involved in the regulation of apoptosis of some cell types by interaction with caspase-3. This work verifies the hypothesis of the abnormal activity of calpains and its role in reduced apoptosis of the B-CLL cells. Casein zymography, reverse transcriptase-polymerase chain reaction, and Western blotting were used for identification and quantification of the activity and expression of calpains in B-CLL cells and purified normal B lymphocytes. The activity and expression of mu-calpain (requiring micromolar Ca(++) for activation) are significantly higher in the leukemic than in nonmalignant cells. Contrarily, the activity and expression of m-calpain (requiring millimolar Ca(++)) as well as the expression of calpastatin (an endogenous inhibitor of calpains) are unchanged or reduced in the B-CLL lymphocytes. Correspondingly, the activity of caspase-3 is many times lower in the B-CLL cells than in normal B lymphocytes. Inhibition of overexpressed mu-calpain in living B-CLL cells in vitro results in doubling of the proportion of the cells undergoing spontaneous apoptosis. This observation suggests a possible role for calpains in longer survival of the B-CLL cells and may open new therapeutic possibilities.

Adult↗