Biomedical subjects

Janusz Zak

Publications and source records attributed to Janusz Zak.

25 records · Page 2Linked to original sources

PubMedDate not supplied

Reticulated platelets as a marker of megakaryopoiesis in liver cirrhosis; relation to thrombopoietin and hepatocyte growth factor serum concentration.

BACKGROUND/AIMS: Thrombocytopenia often accompanies chronic liver diseases. It can occur due to the decrease in blood platelet production by megakaryocytes, the increase in peripheral destruction, or splenic sequestration. METHODOLOGY: We estimate the reticulated platelets by use of flow cytometry in patients with liver cirrhosis with thrombocytopenia (n-24, platelets median (M)-77g/L), with normal platelet count (n-16, platelets M-193g/L) and in healthy (n-27, platelets M-242g/L). The level of reticulated platelets was determined in whole peripheral blood stained with thiazole orange and incubated with monoclonal antibodies anti-CD41. RESULTS: Patients with liver cirrhosis and thrombocytopenia revealed significantly lower reticulated platelet levels than patients without thrombocytopenia and healthy subjects (M-1.0% vs. 1.5% vs. 2.0% respectively). The correlation between reticulated platelet level and platelet count, serum level of thrombopoietin and hepatocyte growth factor in liver cirrhosis was not established. An inverse correlation was noted between reticulated platelets and thrombopoietin (r - 0.6, p<0.01) and hepatocyte growth factor (r - 0.5, p<0.01) in the control group. A positive correlation between platelet count in liver cirrhosis and serum level of thrombopoietin (r - 0.35, p<0.05) and hepatocyte growth factor (r - 0.48, p<0.01) was observed. CONCLUSIONS: Our studies showed that decreased production of platelets by megakaryocytes due to low thrombopoietin concentration could be a possible cause of thrombocytopenia in liver cirrhosis.

Aged↗

PubMedDate not supplied

Evaluation of selected peripheral blood leukocyte functions in patients with various forms of periodontal disease.

INTRODUCTION: Periodontitis (P) is an infectious disease that develops in the supporting tissues of the tooth. One of the risk factors leading to it may be dysfunction of some immune system cells. Therefore, the object of the study was to assess selected functions of peripheral blood leukocytes in patients with various forms of P. As leukocytes are able to secrete interleukin (IL)-4 and IL-6, concentrations of their soluble receptors and the expression of their membrane receptors were investigated. MATERIAL AND METHODS: Twenty generally healthy subjects with aggressive (AP)and chronic periodontitis (CP)were enrolled in the study. The control group consisted of 8 healthy subjects,with no changes in periodontium. Peripheral blood mononuclear cells (PBMCs) were isolated and cultured. Levels of IL-4,IL-6,and their soluble receptors sIL-4R and sIL-6R were determined in the supernatant by ELISA. The expressions of cell surface IL-4R and IL-6R were assayed on PBMC using flow cytometry. RESULTS: No statistically significant differences were found in the selected parameters between people with periodontal disease and healthy controls. However, in subjects with AP, there was an increasing tendency in IL-6 concentration and IL-4R expression on PBMCs. CONCLUSIONS: Our results show that leukocytes play a significant part in P and their activity is probably lesion-dependent. Estimation of the cytokines secreted by leukocytes may facilitate differentiation and prognosis of the disease progression.

Adult↗

PubMedDate not supplied

Lymphocyte subpopulations in peripheral blood in primary sclerosing cholangitis.

BACKGROUND/AIMS: Primary sclerosing cholangitis (PSC) is a chronic disease of autoimmunological etiology, leading to inflammation, destruction and atrophy of the bile ducts. The aim of the study was to determine peripheral lymphocyte B, T, and NK cells in PSC. METHODOLOGY: The estimation of peripheral blood lymphocytes in 17 patients (54+/-12 years old) with PSC was carried out; the control group consisted of 27 subjects (38+/-11 years). The following T lymphocyte subpopulations were determined using duo color flow cytometry: CD3+, CD4+, CD8+, CD3++HLA DR+, B cells CD19+, and NK cells CD16+ +CD56+. RESULTS: In PSC we observed doubled increase in activated T lymphocytes of CD3+ +HLA DR+ phenotype as compared to healthy subjects (7.9% vs. 2.7%, p<0.01) and NK cells (12.6% vs. 10.3%, respectively, p<0.05). There were no significant differences in the composition of CD3+, CD4+, and CD8+. In peripheral blood we noted, in patients with PSC, a decrease in B lymphocytes (11.2% vs. 12.3%, p<0.19). CONCLUSIONS: The examinations showed that activated T (HLA DR+) lymphocytes and NK cells played an important role in development of PSC.

Adult↗

PubMedDate not supplied

Inhibition of activated blood platelets by interferon alpha 2b in chronic hepatitis C.

BACKGROUND/AIMS: Interferon alpha used in treatment of chronic hepatitis C significantly influences the blood platelets. The role of platelets in initiating and developing pathological processes in hepatic diseases is still barely known. We studied the effects of interferon alpha 2b (IFN alpha2b) on blood platelets in chronic hepatitis C. METHODOLOGY: The studies were conducted in 16 patients who underwent IFN alpha2b treatment 3 times a week at 6MU. The examination was carried out before and on the 14th day of the treatment of IFN alpha2b. Morphological parameters of blood platelets were determined by hematological methods and flow cytometry. Expression of receptors on blood platelet surfaces (CD41, CD42a, CD62P) and thrombopoietin, platelet-derived growth factor, soluble form sP-selectin, IL-6, and tumor necrosis factor alpha were also determined. RESULTS: The use of IFN alpha2b in patients with chronic hepatitis C significantly effects blood platelets morphology by causing the decrease in their number, the change in population size, and the increase in large platelet count. Interferon decreases P-selectin expression on platelets, sP-selectin and platelet-derived growth factor concentration in plasma. During interferon therapy we noted increase concentration of thrombopoietin, tumor necrosis factor alpha, IL-6 in chronic hepatitis C. CONCLUSIONS: IFN alpha2b stabilizes activated platelets and probably decreases their participation in inflammatory and fibrotic processes in the liver.

Adult↗

PubMedDate not supplied

[Diagnostic significance of reticulocyte analysis by flow cytometry, in children with acute lymphoblastic leukaemia (ALL) on chemotherapy].

INTRODUCTION: Reticulocytes and their fractions quickly show changes at the time of chemotherapy, therefore they can be an early indicator of changes arising in the erythrocytic line. THE AIM: of the study was an assessment of percentage, absolute number and immature reticulocyte fraction (IFR) by flow cytometry in children with acute lymphoblastic leukaemia (ALL) and comparing them with classical indexes of the erythrocyte line. MATERIAL AND METHODS: The examined group of 14 children from 2 to 16 years with ALL, on remission support treatment (New York II protocol). RESULTS: The group which was treated by thioguanine and cyclophosphamide showed reduction of reticulocytes from mean value 3,1+/-1:1,4 to 2,5+/-1,8. IFR reduction was not significant statistically. In the group treated with vincristine and methotrexate an average percentage of reticulocytes fell from 3.5+/-O.8 to l,5+/-0,4 and IFR did not change significantly. In children who were treated by daunorubicin and cytosine arabinoside an average percentage of reticulocytes reduced from 3.2+/-O,8 to value 2,1+/-1, 7. The immature reticulocyte fraction (IFR) reduced significantly from 22,0+/-6,0 to 12,0+/-8,0 (p<0,03). CONCLUSIONS: The indicators of reticulocytes were reduced after each cycle chemotherapy: this indicates damage in the erythrocyte line. The indicators examined by cytometric method can show changes earlier than classical indicators used in haematology.

Adolescent↗

PubMedDate not supplied

[Immunophenotype of lymphoblastic leukaemia in children in relation to clinical symptoms and laboratory tests, preceding its diagnosis].

The aim of study was to compare the clinical picture and results of laboratory tests according to the acute lymphoblastic leukaemia (ALL) immunophenotype. The observation was carried out on a group of 67 patients treated in the IIIrd Department of Paediatrics and Department of Children Oncology in the Medical Academy of Białystok from January 1994 to April 2001. This group consists of 4 children with pro-B acute lymphoblastic leukaemia, 52 children with pre-B cell ALL, 1 child with B-cell acute lymphoblastic leukaemia and 9 children with T-cell acute lymphoblastic leukaemia. Haemorrhagic diathesis. splenomegaly, enlargement of peripheral lymph nodes as well as higher values of white blood cells count, blasts count, haemoglobin concentration, haematocrit and LDH activity were observed more frequently in patients with T-cell leukaemia than in others.

Blood Cell Count↗

PubMedDate not supplied

Expressions of selected adhesion molecules on peripheral blood leukocytes in patients with aggressive periodontitis.

INTRODUCTION: Aggressive forms of periodontitis lead to rapid bone destruction resulting in extensive losses in children's and young adults' dentition. Adhesion molecule deficiency syndrome and abnormalities in the expression of various adhesion molecules on peripheral blood leukocytes can be observed in prepubertal and aggressive periodontitis (AP) patients. The aim of the study was thus to assess the expression of selected cell adhesion molecules (CAMs; CD11a, CD11b, CD11c, CD54, and CD62L) on monocytes, neutrophils, and lymphocytes of the peripheral blood in patients with AP. MATERIAL/METHODS: The study involved 16 patients with AP and a control group of 13 generally healthy subjects with healthy periodontium. CAM expressions were determined by flow cytometry and presented as mean fluorescence intensity (MFI) and percentage of cells showing expression of the assessed adhesion molecules. RESULTS: Neutrophil CAM expressions in AP patients were comparable with those of the control group. MFI of CD62L on monocytes in AP patients was significantly lower than that of the controls. Lymphocytes showed increased CD11b expression compared with the control group. The percentage of leukocytes showing CAM expression in both groups was similar. Only the percentage of lymphocytes with CD11b in AP patients was significantly higher than in healthy controls. CONCLUSIONS: Because of the evident lack of differences between patients and controls and the great amount of individual dispersion of the results, the above CAMs on peripheral blood leukocytes in generally healthy patients with AP do not seem to be characteristic markers of this disease.

Adult↗