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Biomedical subjects

M Wasik

Publications and source records attributed to M Wasik.

At least 37 records · Page 2Linked to original sources
PubMed1998

The SH3 domain contributes to BCR/ABL-dependent leukemogenesis in vivo: role in adhesion, invasion, and homing.

To determine the possible role of the BCR/ABL oncoprotein SH3 domain in BCR/ABL-dependent leukemogenesis, we studied the biologic properties of a BCR/ABL SH3 deletion mutant (delta SH3 BCR/ABL) constitutively expressed in murine hematopoietic cells. delta SH3 BCR/ABL was able to activate known BCR/ABL-dependent downstream effector molecules such as RAS, PI-3kinase, MAPK, JNK, MYC, JUN, STATs, and BCL-2. Moreover, expression of delta SH3 BCR/ABL protected 32Dcl3 murine myeloid precursor cells from apoptosis, induced their growth factor-independent proliferation, and resulted in transformation of primary bone marrow cells in vitro. Unexpectedly, leukemic growth from cells expressing delta SH3 BCR/ABL was significantly retarded in SCID mice compared with that of cells expressing the wild-type protein. In vitro and in vivo studies to determine the adhesive and invasive properties of delta SH3 BCR/ABL-expressing cells showed their decreased interaction to collagen IV- and laminin-coated plates and their reduced capacity to invade the stroma and to seed the bone marrow and spleen. The decreased interaction with collagen type IV and laminin was consistent with a reduced expression of alpha 2 integrin by delta SH3 BCR/ABL-transfected 32Dcl3 cells. Moreover, as compared with wild-type BCR/ABL, which localizes primarily in the cytoskeletal/membrane fraction, delta SH3 BCR/ABL was more evenly distributed between the cytoskeleton/membrane and the cytosol compartments. Together, the data indicate that the SH3 domain of BCR/ABL is dispensable for in vitro transformation of hematopoietic cells but is essential for full leukemogenic potential in vivo.

Animals↗
PubMed1998

CD34+, kit+, rhodamine123(low) phenotype identifies a marrow cell population highly enriched for human hematopoietic stem cells.

We hypothesized that human hematopoietic cells displaying a CD34+, kit-, rhodamine123(low) phenotype would be highly enriched for cells with stem-like properties. To test this hypothesis, we employed fluorescence activated cell sorting (FACS) to isolate cells with this phenotype from normal light density marrow mononuclear cells (MNC). CD34+, kit+, rhodamine123(low) cells comprised from 0.05-0.01% of the total MNC population. They were small, had scant cytoplasm, and contained nuclei with dense, hyperchromatic chromatin and inconspicuous nucleoli. Additional immunophenotyping revealed that these cells were CD33-, CD38-, CD20-, and glycophorin A-. When plated in semisolid cultures containing optimal concentrations of IL-3, GM-CSF, KL, EPO, IL-6, and IL-1 these cells did not form colonies. However, when cultured over irradiated stromal cells, cobblestone areas were observed to form after 3 weeks, and harvested cells were able to initiate long-term cultures. To further demonstrate that these cells were indeed stem like, we also tested their ability to engraft and mature in immunocompromised (SCID) mice. Irradiated (400 cGy) SCID mice were transplanted with 2 x 10(3) candidate stem cells which were then injected with recombinant human growth factors every other day. Two months post-transplant the animals were sacrificed. PCR and FACS analysis of marrow and spleen cell samples revealed the presence of cells expressing human CD45 consistent with engraftment of human stem cells and the establishment of murine-human chimerism. Moreover, MNC isolated from transplanted mice formed unambiguously human BFU-E, CFU-GM and B cell colonies when stimulated with the appropriate growth factors. Accordingly, we have identified a relatively rapid and simple mechanism for isolating primitive human hematopoietic cells with stem cell-like properties. We anticipate that this strategy will be useful for experimental and therapeutic applications that require human stem cells in quantity.

Animals↗
PubMed1998

Epidemiology of collegiate baseball injuries.

OBJECTIVE: We sought to establish injury incidence, onset, location, type, and severity for a collegiate baseball team. The second objective was to compare the number of musculoskeletal problems for which baseball players sought treatment with those that resulted in time lost or modified participation. METHODS: This was a prospective, epidemiologic study. A complaint was defined as any evaluation by a player to the medical staff that required either evaluation or treatment. An injury was defined as any complaint that resulted in altered participation or time lost from practice or game participation. Participants were Division I collegiate baseball team with one athletic trainer and one academic sports medicine specialist. All members of the collegiate baseball team were studied over a 3-year period to determine the overall incidence of injury per 1,000 exposures (A-E) to practice or participation, injuries sustained over 3 years by collegiate baseball players. RESULTS: Overall there were 277 complaints and 52 injuries (19%). The A-E rate was 5.83. Forty-six percent of the injuries occurred in practice and 54% in games. Seventy-three percent of the injuries resulted in < 7 days lost from sport, and 25% resulted in > 21 days lost participation. The most common origin of injury was strains (23%), sprains (19%), and contusions (17%). Fifty-eight percent of the injuries were to the upper extremity, 15% to the trunk/back, and 27% to a lower extremity. Upper extremity injuries accounted for 75% of the total time lost from the sport. When divided by position, the shoulder injuries occurred in pitchers (69%), infielders (19%), and outfielders (12%). Rotator cuff tendinitis was the most frequent complaint, was the most frequent injury, and resulted in the most time lost from the sport. CONCLUSIONS: Defining injury as time lost or as altered participation underestimates the frequency with which players seek evaluation and treatment. Injuries are divided widely across anatomic site, but upper extremity injuries cause the most time lost from the sport. Further study of the origin and prevention of upper extremity injuries in baseball is warranted.

Adult↗
PubMed1998

[DNA index determined by flow cytometry in children with acute lymphoblastic leukemia as an additional diagnostic and prognostic element].

The aim of the study was to establish the frequency of aneuploidy in bone marrow and peripheral blood cells in children with acute lymphoblastic leukemia (ALL) and to determine DNA index (DI), as an additional prognostic factor. The DNA content of cells was determined by flow cytometry using propidium iodide staining. The bone marrow and peripheral blood of 22 children were examined at the time of diagnosis. The diploid cell population (DI = 1) was found in 10 children (45%). Hiperdiploidy was found in 12(55%) children. DI > or = 1.16 was found in 7 children (32%) and 1 < DI < 1.6 in 5 children (23%). In one patient with DI > 1.16 two hiperdiploidal cell populations were found. In another one hipodiploidy with a hiperdiploidal cell populations coexisted. DI was compared with other prognostic factors--initial leukocyte count, immunophenotype, reaction to the treatment.

Adolescent↗
PubMed1998

[BCL-2 antigen expression in blood cells in children suffering from leukemia].

It was established that high level of BCL-2 antigen inhibited suicidal cell death and prevented apoptosis induced by antitumor drugs. Due to the fact that evaluation of BCL-2 expression in bone marrow and peripheral blood cells could be an important prognostic factor in patients with malignant hematopoietic diseases, we decided to study the number of BCL-2+ nuclear cells and assess this antigen expression in the cells. Using monoclonal FITC-conjugated antibody, antigen BCL-2 was found in peripheral blood cells in children with both lymphoblastic (ALL) and non-lymphoblastic leukemia (NLL). At the same time the percentage of PCNA+ blood nuclear cells was investigated. The cells were analysed with a flow cytometer. The study carried out in a group of 12 ill and 7 healthy children showed significantly increased percentage of lymphocytes and neutrophiles PCNA+ and BCL-2+ in ALL, in comparison with a healthy control group. Exclusively an increased percentage of BCL-2+ lymphocytes and neutrophiles was observed in NLL patients. Due to a relatively small group of investigated patients we can not make a certain conclusion but preliminary analysis suggests a correlation between a high number of BCL-2+ cells and a long time without remission.

Adolescent↗
PubMed1998

[Myelogenous system cells' activity in the bone marrow in children with acute leukemia remission].

Myelogenic system cells' activity was evaluated in 12 bone marrow samples taken from the children in acute leukemia's remission period and 7 samples from the patients in whom malignant disease of the hematopoietic system was ruled out. Cell activity was evaluated with the nFMLP induced chemiluminiscence test (CL) in the luminol environment. In the bone marrow of the patients in the period of acute leukemia remission the cells' chemiluminiscence was, considerably higher than in the control material. It appears that in the acute leukemia's remission period a functional regeneration of the myeloid line cells occurs.

Adolescent↗
PubMed1998

The effect of salbutamol treatment on the cellular immunity of the offspring of pregnant mice: spleen cell activity.

Preterm delivery is one of the greatest problems in obstetric care. One of the most commonly used treatments for high risk cases is salbutamol, a beta-2-adrenoceptor agonist. The aim of the present study was to determine if such treatment causes any changes in the neonatal immune system which should therefore be a concern in the care of the newborn. The experiments were performed on 4 to 5 or 6 to 7-week old female and male offspring of salbutamol-treated C3H/W inbred mice. In the first part of the study, the number of spleen cells, phenotypes and activity (phytohemagglutinin-induced proliferation, ability to induce local graft versus host reaction) were determined. We observed lowering of cell number and lowered proportions of cluster of differentiation (CD)3, CD4 and CD8 positive lymphocytes in spleens of progeny of salbutamol-treated mice. However, CD4+ to CD8+ ration was higher in the progeny of salbutamol-treated mothers than in the corresponding controls. In addition, reactivity to phytohemagglutinin and ability to induce local graft vs. host reaction were higher (popliteal lymph node test) or undisturbed (lymphocyte-induced angiogenesis test) in this group of mice.

Adrenergic beta-Agonists↗
PubMed1997

Effect of hepatocyte growth factor on early human haemopoietic cell development.

Hepatocyte growth factor (HGF) stimulates cell proliferation, differentiation and migration by binding to its receptor, MET R. Whether the HGF/MET R axis plays an important regulatory role in human haemopoietic cell growth is an unresolved issue. To investigate this situation, we employed several complementary strategies including RT-PCR, FACS analysis, and mRNA perturbation with oligodeoxynucleotides (ODN). We found that very primitive, FACS sorted, CD34+ Kit+ marrow mononuclear cells (MNC) failed to express RT-PCR detectable MET R mRNA. In contrast, MET R expression was easily detectable by RT-PCR in marrow stroma fibroblasts, in cells isolated from BFU-E and CFU-GM colonies, and in unselected normal MNC. Subsequent FACS analysis revealed that MET R protein was detectable on approximately 5% of the latter cells. HGF, at concentrations of 1-50 ng/ml, had no demonstrable effect on survival or cloning efficiency of normal CD34+ MNC in serum-free cultures. Antisense ODN mediated perturbation of MET R mRNA expression in normal CD34+ MNC, with FACS documented decline in protein expression, had no effect on the ability of these cells to give rise to haemopoietic colonies of any lineage. We also examined the biology of HGF/MET R expression in malignant haemopoietic cells. Using the strategies described above, we found that MET R mRNA was expressed in many human haemopoietic cell lines, and that the protein was expressed at high levels on HTLV transformed T lymphocytes. Wild-type CML and AML blast cells also expressed MET mRNA, and HGF was able to co-stimulate CFU-GM colony formation in approximately 20% of cases studied. Therefore, although the HGF/MET R axis appears to be dispensable for normal haemopoietic cell growth, it may play a role in the growth of malignant haemopoietic progenitor cells.

Cell Line↗
PubMed1997

[Selected cellular immunity parameters in patients with Lesniowski-Crohn disease].

The study was aimed at investigating the expression of HLA-DR, CD4, CD8, CD56 and CD16 surface antigens on peripheral blood lymphocytes in patients with Crohn's disease. The percentage of rosette-forming T-cells in theophylline test was assessed simultaneously. The experiment at group consisted of 18 patients (aged 16-66) of long standing Crohn's disease history, being in the remission period and not treated by steroid antiinflammatory drugs. The percentage of lymphocytes with HLA-DR, CD4, CD8, CD56 and CD16 surface antigens was examined by means of the monoclonal antibodies (DAKO), and the APAAP procedure. The immunological test included also an assessment of the number of T-cells forming active (ARFC) and total (TRFC) rosettes in the theophylline test. Significantly increased (p < 0.001) percentage of lymphocytes with HLA-DR surface antigens was observed in patients with Crohn's disease. The percentage of lymphocytes with CD4, CD8, CD56 and CD16 surface antigens did not differ significantly from the control group, although the tendency for increase in the percentage of lymphocytes with CD8 surface antigens was clearly marked. The ratio of lymphocytes with CD4 to CD8 surface antigens and the number of T-cells forming active and total rosettes were significantly lower (p < 0.05) in patients with Crohn's disease. In 10 of 18 patients the number of T-cells forming active and total rosettes was lower than 500 cells in 1 mm3 peripheral blood. In addition particular notice should be given to the fact that no T-cells reaction to theophylline was obtained in patients' group. The results suggest significant cellular immunoreactivity disturbances which may be the result of the persisting intestinal mucosa's inflammation in patients with Crohn's disease being in the remission period. The studies of peripheral blood lymphocytes with HLA-DR surface antigens may have significance in Crohn's disease's clinical monitoring.

Adolescent↗
PubMed1997

Changes in the phagocytic cells in children treated with continuous ambulatory peritoneal dialysis.

Children on continuous ambulatory peritoneal dialysis (CAPD) in endstage renal failure are highly exposed to peritonitis. Peritoneal macrophages (PM) and blood neutrophils (PMNC) are the first line of defense against invading microbes. This study was undertaken for assessing surface receptors expression on PM and PMNC and to check their ability to phagocytosis and killing of bacteria. We have found that in spite of the decreased number of PM in dialysate fluid their viability and activity significantly increased during CAPD. Moreover, higher number of PM expressed CD16 and CD35 antigens (FcRIII and C3bR, respectively) in comparison with the results observed at CAPD onset. The number of PMNC expressed of these two antigens in uremic children blood were significantly lower in comparison with healthy control. The number of CD16 positive cells increased under influence of CAPD only temporarily. CAPD caused improvement of phagocytosis and intracellular killing of bacteria by PM but not by PMNC. There is discussed here influence of uremia and CAPD on surface antigens, function of phagocytes as well as renewal of PM during CAPD.

Adolescent↗
PubMed1996

Injuries in female collegiate swimmers due to swimming and cross training.

OBJECTIVE: To identify and compare the nature and frequency of training and cross-training injuries incurred by members of a women's collegiate swim team. DESIGN: A longitudinal survey of training-room and medical records for 7 years, classifying injuries by diagnosis and time lost from participation. SETTING: Division I women's collegiate swimming program, United States. PARTICIPANTS: All swimmers in a Division I women's collegiate swimming program over 7 years, for a total of 68 swimmers. ASSESSMENT OF RISK FACTOR: Not applicable. INTERVENTION: Not applicable. MAIN OUTCOME MEASURES: "Injury" was defined as any contact with a trainer or physician that resulted in evaluation or treatment. Each injury was categorized with respect to (a) activity during which injury was incurred; (b) diagnosis, including body part injured; (c) time lost from participation in practice or competition; and (d) severity, i.e., minor (< or = 7 days), moderate (7-21 days), and major (> 21 days). An "Exposure" was defined as participation in one practice session or competition. MAIN RESULTS: The overall injury rate per 1,000 exposures per athlete was 2.12; 44% of injuries were due to swimming, 44% to cross training, and 11% to activities unrelated to athletics. Cross-training injuries occurred primarily in the lower extremities, while swimming injuries occurred more commonly in the upper extremities. The ratio of upper to lower extremity injuries due to swimming was 3:1, whereas the ratio for cross training was 1:4. CONCLUSIONS: Injuries to swimmers occur at a lower rate per exposure than to other collegiate athletic populations. Swimming injuries occurred primarily in the upper extremities, especially the shoulder. Lower extremity injuries occurred primarily due to cross training. We conclude that swimming is relatively safe compared to other collegiate sports, but special care should be used in designing injury-avoiding cross-training programs.

Athletic Injuries↗
PubMed1995

Antitumor activity of anti-CD30 immunotoxin (Ber-H2/saporin) in vitro and in severe combined immunodeficiency disease mice xenografted with human CD30+ anaplastic large-cell lymphoma.

To develop a novel adjunctive therapy for CD30 (Ki-1)+ anaplastic large-cell lymphoma (ALCL), we investigated in preclinical studies the antitumor activity of an immunotoxin (IT) constructed by coupling the plant ribosome-inactivating protein saporin (SO6) to the monoclonal antibody (MoAb) Ber-H2 that is directed against the CD30 molecule, a new member of the tumor necrosis factor receptor (TNFR) super-family. The activity of Ber-H2/SO6 IT was tested both in vitro against the CD30+ ALCL-derived cell line JB6 and in vivo using our severe combined immunodeficiency disease (SCID) mouse model of human xenografted CD30+ ALCL. In vitro, the Ber-H2/SO6 IT was selectively and highly toxic to the JB6 cell line [50% inhibiting concentration (IC50), 3.23 x 10(-12) mol/L as SO6]. In vivo, a 3-day treatment with nontoxic doses of Ber-H2/SO6 (50% of LD50) induced lasting complete remissions (CR) in 80% of mice when started 24 hours after tumor transplantation. In contrast, injection of the IT at later stages of tumor growth (mice bearing subcutaneous tumors of 40- to 60-mm3 volume), induced CR in only 6 of 21 (approximately 30%) mice and significantly delayed tumor growth rate (P < .01). This finding suggests that maximum effect of the anti-CD30 IT is observed when tumor cell burden is small. Persistent tumors from IT-treated mice consisted of CD30+ cells, thus excluding the possibility that selection of CD30-negative mutant clones during IT therapy was responsible for resistance to treatment. We conclude that Ber-H2/SO6 IT is an effective agent against CD30+ ALCL growing in SCID mice, suggesting its possible role as adjuvant therapy in patients with CD30+ ALCL refractory to standard treatments.

Animals↗
PubMed1994

Heparin enhances generation of natural killer activity in vitro.

The effect of heparin on generation and activity of NK cells in vitro were studied. Heparin decreased NK cytotoxicity when present in the assay. In contrast, the agent increased generation of NK cytotoxicity and showed synergistic action with recombinant IL2.

Adjuvants, Immunologic↗
PubMed1993

Immunomodulating effects of heparin on human B cell proliferation.

Recent data indicate that heparin may act as an immunomodulator. In this paper we have analyzed the effects of this agent on human B cell proliferation in vitro induced by S. aureus Cowan. The action of heparin is complex, but there was a trend for inhibition of B cell responses obtained from defibrinated but not heparinized blood samples. This suggests that heparin interacts with platelet products (growth factors, cytokines) and the results of such interactions determine the final effect.

Adjuvants, Immunologic↗
PubMed1992

The role of cow's milk protein intolerance in steroid-resistant nephrotic syndrome.

The role of cow's milk protein intolerance in steroid-resistant nephrotic syndrome was evaluated in 17 children. Cow's milk was excluded from the diet for at least 14 days without changing previously ineffective prednisone dosage. Six patients with minimal change or mesangial proliferation went into remission 3 to 8 days after elimination of cow's milk. After a period of 2-3 weeks of remission, cow's milk challenge was positive in three patients. After one year on a cow's milk-free diet, two of six patients became milk tolerant and are in remission of NS, one of six became steroid-dependent, two of six are still unable to tolerate cow's milk and are in remission on a cow's milk-free diet and one of six children was lost from observation. The role of cellular mechanisms in steroid-resistant nephrotic syndrome is suggested.

Adolescent↗
PubMed1992

Cytomegalovirus pseudotumor presenting as bowel obstruction in a patient with acquired immunodeficiency syndrome.

Although cytomegalovirus (CMV) can be fatal to patients with the acquired immunodeficiency syndrome (AIDS), it usually causes few, if any, symptoms. The virus has an affinity for the alimentary tract, especially the ileum and right colon. CMV infections of the gut are often erosive, resulting in enterocolitis, hemorrhage, or intestinal perforation. Inflammatory mass formation is rare. Kaposi's sarcoma and lymphoma are established causes of bowel obstruction in patients with AIDS. This report describes a case of ileocecal obstruction due to a discrete CMV-induced pseudotumor in a patient with AIDS.

Acquired Immunodeficiency Syndrome↗