Biomedical subjects

I Ben-Bassat

Publications and source records attributed to I Ben-Bassat.

At least 19 recordsLinked to original sources

PubMed2002

Activated macrophages for treating skin ulceration: gene expression in human monocytes after hypo-osmotic shock.

Macrophages play a major role in almost all stages of the complex process of wound healing. It has been previously shown that the incorporation of a hypo-osmotic shock step, in the process of monocyte-concentrate preparation from a blood unit, induces monocyte/macrophage activation. As the macrophages are produced using a unique, closed and sterile system, they are suitable for local application on ulcers in elderly and paraplegic patients. Enhanced phagocytosis by the activated cells, as well as increased secretion of cytokines such as IL-1, IL-6, were detected in a recent study which are in accord with the very encouraging clinical results. In the present study, we used DNA microarrays to analyse the differential gene expressions of the hypo-osmotic shock-activated monocytes/macrophages and compare them to non-treated cells. Of the genes that exhibited differences of expression in the activated cell population, 94% (68/72) displayed increased activity. The mRNA levels of 43/68 of these genes (63%) were found to be 1.5-fold or higher (1.5-7.98) in the activated macrophages cell population as compared to the non-treated cells. Only four genes were found to have lower mRNA levels in the activated cells, with ratios of expression of 0.62-0.8, which may suggest that the changes are insignificant. A significant number of the genes that showed increased levels of expression is known to be directly involved in macrophage function and wound healing. This may correlate with the increased secretion of different cytokines by the activated macrophages depicted previously. Other groups of genes expressed are known to be involved in important pathways such as neuronal growth and function, developmental defects and cancer. The hypo-osmotic shock induces a gene expression profile of cytokines and receptors in the activated cells. These may evoke potential abilities to produce a variety of protein products needed in the wound healing process and may bring to light possibilities for other therapeutic applications of these cells.

Cell Culture Techniques↗

PubMed2001

Genetic basis of hemolytic anemia caused by pyrimidine 5' nucleotidase deficiency.

Pyrimidine 5' nucleotidase (P5'N-1) deficiency is an autosomal recessive condition causing hemolytic anemia characterized by marked basophilic stippling and the accumulation of high concentrations of pyrimidine nucleotides within the erythrocyte. It is implicated in the anemia of lead poisoning and is possibly associated with learning difficulties. Recently, a protein with P5'N-1 activity was analyzed and a provisional complementary DNA (cDNA) sequence published. This sequence was used to study 3 families with P5'N-1 deficiency. This approach generated a genomic DNA sequence that was used to search GenBank and identify the gene for P5'N-1. It is found on chromosome 7, consists of 10 exons with alternative splicing of exon 2, and produces proteins 286 and 297 amino acids long. Three homozygous mutations were identified in this gene in 4 subjects with P5'N-1 deficiency: codon 98 GAT-->GTT, Asp-->Val (linked to a silent polymorphism codon 92, TAC-->TAT), codon 177, CAA-->TAA, Gln-->termination, and IVS9-1, G-->T. The latter mutation results in the loss of exon 9 (201 bp) from the cDNA. None of these mutations was found in 100 normal controls. The DNA analysis was complicated by P5'N-1 pseudogenes found on chromosomes 4 and 7. This study is the first description of the structure and location of the P5'N-1 gene, and 3 mutations have been identified in affected patients from separate kindreds. (Blood. 2001;97:3327-3332)

5'-Nucleotidase↗

PubMed2001

Engraftment-associated hypophosphatemia--the role of cytokine release and steep leukocyte rise post stem cell transplantation.

Hypophosphatemia associated with bone marrow transplantation has been infrequently reported. The suggested mechanism is phosphate uptake by the replicating cells. Various cytokines are associated with the development of hypophosphatemia. The present study evaluated the interrelationship between cytokine release, the rise in WBC and the development of hypophosphatemia during the engraftment period. Blood samples were obtained from 60 patients undergoing peripheral blood stem cell transplant, on the day of admission and then daily from the day of transplant until discharge. Hypophosphatemia developed in 62% of the patients. The median day of minimal phosphorus level was +8 and it antedated engraftment by 2 days. There was a significant correlation between the day of minimal phosphorus level and the day of maximal WBC and a significant correlation between the fall in phosphorus level and WBC rise. IL-6 and IL-8 showed similar kinetics. Higher IL-6 and IL-8 levels were directly associated with lower phosphorus levels. In conclusion, hypophosphatemia commonly occurs in the post-transplant period. We assume that both a direct effect of cytokine release and an increased consumption by the dividing WBCs contribute to its appearance. As its occurrence usually antedates engraftment it can be used as a forerunner for WBC recovery.

Adult↗

PubMed2001

Activation of human monocytes/macrophages by hypo-osmotic shock.

Phagocytosis and secretion of interleukins and growth factors put the macrophage in the centre of the wound healing process. For the last four years over 400 human ulcers have been treated in elderly and paraplegic patients by local application of monocytes prepared from a blood unit, in a unique, closed, sterile system. The process of preparation includes a step of hypo-osmotic shock, which induces monocyte/macrophage activation. This is different from any other known method of activation. In the present study we evaluated the efficacy of the hypo-osmotic shock. We found enhanced levels of IL-1 (P = 0.004) and IL-6 (P = 0.001) in the incubation medium (100% autologous serum) of the activated cells, as compared with controls, prepared in the same system. The IL-1 reached a plateau after 6 and 12 h incubation at 37 degrees C, in both experimental and control incubation medium. The level of IL-6 was further elevated after 12 and 24 h incubation in experimental and control incubation mediums (P = 0.001). The phagocytosis of fluorescent beads was markedly enhanced after hypo-osmotic shock (P = 0.005). The osmotic shock induced macrophages were compared to those stimulated with LPS, and osmotic shock was proved to be at least as efficient method of stimulation as LPS.

Culture Media, Conditioned↗

PubMed2001

Extramedullary progression despite a good response in the bone marrow in patients treated with thalidomide for multiple myeloma.

We report two patients who were treated with thalidomide for resistant multiple myeloma (MM) and developed extramedullary plasmacytomas despite a good response in the bone marrow. The first patient had progressive disease 18 months post autologous peripheral stem cell transplant. Two and a half months after the initiation of thalidomide therapy extensive new plasmacytomas of the skin and nasal mucosa appeared while the medullary response continued. The second patient was treated with thalidomide for resistant MM. Despite a medullary response he developed neurological signs compatible with cranial nerve involvement and an MRI study was suggestive of a plasmacytoma involving the sellar region. We assume that a change in the expression of some adhesion molecules on the myeloma and/or the stromal cells is responsible for this phenomenon. Treating Physicians should be aware of this phenomenon in MM patients receiving thalidomide.

Adult↗

PubMed2000

Linkage analysis for major histocompatibility complex-related genetic susceptibility in familial chronic lymphocytic leukemia.

Chronic lymphocytic leukemia (CLL) shows evidence of familial aggregation, but the genetic basis is poorly understood. The existence of a linkage between HLA and Hodgkin lymphoma, another B-cell disorder, coupled with the fact that CLL is frequently associated with autoimmune disease, led to the question of whether the major histocompatibility complex (MHC) region is involved in familial cases of CLL. To examine this proposition, 5 microsatellite markers on chromosome 6p21.3 were typed in 28 families with CLL, 4 families with CLL in association with other lymphoproliferative disorders, and 1 family with splenic lymphoma with villous lymphocytes. There was no evidence of linkage in these families to chromosome 6p21.3. The best estimates of the proportions of sibling pairs with CLL that share 0, 1, or 2 MHC haplotypes were not significantly different from the null expectation. This implies that genes within the MHC region are unlikely to be the major determinants of familial CLL. (Blood. 2000;96:3982-3984)

Adult↗

PubMed2000

Standardization criteria for the detection of BCR/ABL fusion in interphase nuclei of chronic myelogenous leukemia patients by fluorescence in situ hybridization.

Fluorescence in situ hybridization (FISH), as a new clinical test, is not presently standardized. For practical reasons, each laboratory must build its own criteria. In this work, we present our standardization criteria for clinical practice, which include not only the methods for cell fixation, specimen preparation, and hybridization conditions, but mainly the definition of false-positive range and the scoring criteria of microscopic analysis. These include signal assessment, difference between individual microscopists, evaluation of specimen homogeneity, and the minimum number of scored nuclei required for a clinically reliable result. For this purpose, we analyzed by FISH 24 healthy volunteer donors, 31 patients affected by non-chronic myelogenous leukemia (CML) hematological malignancies, 47 CML patients at diagnosis, and 82 CML patients during treatment for the BCR/ABL fusion. In this article, we present several quality control and assurance methods that can be useful in providing standardization of the FISH technique.

Cell Nucleus↗

PubMed2000

Therapy with thalidomide in refractory multiple myeloma patients - the revival of an old drug.

We have treated 17 refractory or relapsed multiple myeloma patients resistant to chemotherapy with thalidomide at a dose of 200-800 mg/day. Eleven patients responded, five of whom had a very good partial response (> 75% decline in M protein) and another five exhibited a partial response (> 50% decline in M protein). Except for one patient, treatment was well tolerated with only mild side-effects. Thalidomide should be included in the therapeutic options for refractory myeloma.

Adult↗

PubMed2000

Diffuse alveolar hemorrhage in acute promyelocytic leukemia patients treated with ATRA--a manifestation of the basic disease or the treatment.

All-trans-retinoic acid (ATRA) is considered the recommended induction treatment for acute promyelocytic leukemia. In the pre-ATRA era pulmonary bleeding was a common cause of death in these patients, mostly due to disseminated intravascular coagulation which was further exacerbated by the administration of chemotherapy. Although ATRA syndrome, the most serious adverse effect of ATRA treatment, involves the lungs, pulmonary hemorrhage has only rarely been reported as a manifestation of ATRA syndrome. Here we describe 2 patients who developed diffuse alveolar hemorrhage during treatment with ATRA. The possible mechanisms of pulmonary bleeding in these cases are discussed.

Adult↗

PubMed2000

[High-dose chemotherapy and autologous stem cell transplantation for refractory and relapsing Hodgkin's disease as first-line therapy-- studies at Sheba Medical Center--Tel Hashomer].

High dose chemotherapy and autologous stem cell transplantation are widely used in relapsed and primary refractory Hodgkin's disease. We transplanted 42 patients with Hodgkin's disease between 1990-1998. Median follow-up was 31 months (range 1-102). 29 (69%) were transplanted after relapse and 13 (31%) were refractory to first line therapy. Median age at transplantation was 29 years (range 19-58) and 23 (55%) were males. All were treated with the BEAM protocol (carmustine, etoposide, cytarabine and melphelan). 18 who were in remission received radiotherapy following transplantation. The source of the stem cells was bone marrow in 17% and peripheral blood in 83%. At initial diagnosis: 57% had stage III-IV disease and B symptoms were present in 52%. 75% were treated with MOPP, ABVD or with related versions. Radiotherapy followed in 52%. Prior to transplantation, 45% of the relapsed group were in the advanced stage. 33% and 12% of all patients had lung and bone involvement, respectively. The complete remission rate was 86% for the 2 groups. 2 (5%) died from transplant-related complications and MDS/AML developed in 2 (5%) after transplantation. The 3-year overall survival (OS) and disease-free survival (DFS) were 68% and 60%, respectively. The 3-year OS for the relapsed group was 64% compared with 76% for the refractory group, and the 3-year DFS for the relapsed group was 60% vs. 42% for the refractory group (neither difference significant). Radiotherapy following transplantation did not have a beneficial effect on DFS. No prognostic factors for outcome of transplantation were found, most probably due to the limited number of patients and the high variability of disease characteristics. We conclude that high dose chemotherapy and autologous stem cell transplantation are effective and relatively safe for relapsed or primary refractory Hodgkin's disease. The DFS at 3 years was longer for those transplanted after relapse than those with primary refractory disease, but not significantly. Patients with primary refractory disease can be salvaged with high dose chemotherapy.

Adult↗

PubMed2000

[Treatment of adults with acute lymphoblastic leukemia--results at the Sheba Medical Center, Tel-Hashomer, 1977-1988].

Acute lymphoblastic leukemia (ALL) is a malignant disease whose incidence is relatively low among adults, unlike in children. Adults with ALL have a lower rate of long-term disease-free survival. During the last 20 years, a German multicenter group has shown that their protocols have achieved good results in adults ALL. We reviewed the medical records of 35 ALL patients, aged 19-63 years, whom we treated with these protocols (1988-1997). The remission rate was 94%. At a median follow-up of 46 months the 2-year overall survival was 54% and the disease-free survival was 94%. Although 2 patients died of bone marrow transplant complications, no death was directly associated with drug toxicity. The main grade 3 or 4 side effects (WHO classification) were neutropenia (91%), thrombocytopenia (71%) and anemia (71%). With there protocols we achieved high overall and disease-free survival rates, especially in comparison with other reports. Despite the high rate of severe treatment toxicity, there were no fatalities directly related to treatment. These results emphasize the need to concentrate treatment of adult ALL patients in large medical centers with expertise in the use of the complicated treatment protocols required.

Adult↗

PubMed1999

Salvage therapy of refractory and relapsed acute leukemia with high dose mitoxantrone and high dose cytarabine.

We have assessed the outcome of 66 refractory and relapsed acute leukemia patients treated with high dose mitoxantrone and cytarabine. Therapy consisted of a total dose of 40-60 mg/m2 mitoxantrone and 3 g/m2 of cytarabine daily on 5 consecutive days. A total of 28 patients were treated for primary resistant and 38 patients for early or late relapsed leukemia. A total of 35 patients achieved CR. Four patients died during the induction course. Toxicity was acceptable and comparable to other salvage regimens. The median disease-free and overall survivals were 4 and 6 months, respectively. Although this regimen is effective in achieving remission in refractory leukemia, its duration is short.

Acute Disease↗

PubMed1999

Rheumatic manifestations preceding adult acute leukemia: characteristics and implication in course and prognosis.

The manifestations and outcome of adult patients with acute leukemia (AL) were examined to study the characteristics of the rheumatological prodrome of AL and to find whether it is a marker of a distinct clinical and laboratory course and whether it has any prognostic implication. During a 10-year period, 8/139 (5.8%) of AL patients presented with rheumatic manifestations. The average duration of the arthritis syndrome preceding the diagnosis of AL was 3.25 months. The most common pattern of presentation was a reactive arthritis-like syndrome involving the large joints asymmetrically and associated with low back pain. Distinctive features suggesting a paraneoplastic arthritis were severe pain disproportionate to physical findings, a poor response to conventional antirheumatic treatment, and early significant osteopenia or lytic bone lesions. The epidemiological, clinical and laboratory characteristics of patients with or without rheumatic manifestations were comparable, except for fever on presentation, the presence of transient metabolic derangement following chemotherapy, and the initial average hemoglobin, hematocrit and serum uric acid values. Moreover, the initial outcome of the two groups was similar, as the early mortality rates were comparable (42.8% vs. 45% for patients with or without arthritis, respectively). In conclusion, rheumatic syndrome presentation of adult AL is uncommon, and apparently has no deleterious effects on initial prognosis. A timely diagnosis requires an increased awareness to distinctive features.

Acute Disease↗

PubMed1999

Acute neutrophilic dermatosis induced by all-trans-retinoic acid treatment for acute promyelocytic leukemia.

All-trans-retinoic acid (ATRA) is considered the recommended induction treatment for acute promyelocytic leukemia (APL). Although the dermatological side effects associated with ATRA treatment are relatively common, acute neutrophilic dermatosis (Sweet's syndrome) has only been rarely reported. We describe such a case who responded to chemotherapy and not to low doses of corticosteroids.

Antineoplastic Agents↗

PubMed1998

Incidence and outcome of hepatic veno-occlusive disease after blood or marrow transplantation: a prospective cohort study of the European Group for Blood and Marrow Transplantation. European Group for Blood and Marrow Transplantation Chronic Leukemia Working Party.

To determine the incidence and outcome of hepatic veno-occlusive disease (VOD) after blood or marrow transplantation (BMT), we prospectively evaluated all consecutive patients receiving a BMT during a 6-month period in participating EBMT centers. All of them were evaluated for occurrence of VOD according to previously defined clinical criteria. The clinical course, outcome, value of prophylactic and therapeutic interventions, and the influence of previously described risk factors were analyzed. During the study period, 1,652 BMT were performed in 73 centers. VOD was diagnosed in 87 patients (5.3%; 95% confidence interval [CI], 4.2% to 6.4%). Fifty-six of 631 allogeneic BMT (8.9%) and 31 of 1,010 autologous BMT (3.1%) developed this complication (P <.0001). VOD was classified as mild in 7 (8%), moderate in 56 (64.4%), and severe in 24 (27.6%) cases. Sixteen patients died of VOD (corresponding to 1% of the whole series, 18.4% of VOD patients, and 66.7% of severe VOD). The use of unfractionated heparin did not significantly decrease the incidence of VOD. Independent variables associated with an increased risk of VOD were allogeneic BMT (relative risk [RR], 2.8; P <.001), pre-BMT elevation of serum aspartate aminotransferase (RR, 2.4; P =.001), high-dose cytoreductive therapy (RR, 2.3; P =.003), Karnofsky performance score less than 90% (RR, 2.7; P =.006), and prior abdominal radiation (RR, 2.9; P =.03). In conclusion, this prospective study shows that (1) the incidence of VOD is lower than that reported in smaller studies from single centers, (2) about one fourth of cases of VOD progress to severe disease, (3) main risk factors have a major impact on incidence of VOD, and (4) the use of prophylactic unfractionated heparin does not seem to reduce the incidence of VOD.

Adult↗

PubMed1998

The MACOP-B and VACOP-B combination chemotherapy for young patients with intermediate-grade non-Hodgkin's lymphoma.

Since the early 1970s, three generations of combination chemotherapy for intermediate-grade non-Hodgkin's lymphomas (NHL) have been developed. One of the third-generation regimens is MACOP-B (methotrexate, doxorubicin, cyclophosphamide, vincristine, prednisone, and bleomycin). The VACOP-B regimen is a modification of MACOP-B in which methotrexate is omitted and etoposide is added. This study assesses treatment outcome using the MACOP-B and VACOP-B combination chemotherapy in a population of young patients with intermediate-grade NHL treated in a single tertiary hematological center. The files of 45 patients aged 18-55 who were diagnosed as having intermediate-grade NHL (working formulation types F-H) and treated between January 1986 and March 1994 were reviewed. Treatment response, overall survival, disease-free survival and treatment toxicity were determined. The predictive value of the age-adjusted international prognostic index was also assessed. Median follow-up was 80 months in the MACOP-B group and 29 months in the VACOP-B group. The complete response rate was 71% (95% confidence interval CI: 58-84), 4-year overall survival was 74 +/- 7% and 4-year disease-free survival was 79 +/- 8%. No toxicity-related deaths were observed. The main adverse effects were WHO grade 3 or 4 neutropenia (51%), anemia (24%) and mucositis (20%). Only the CR rate was correlated with the Age-Adjusted International Prognostic Index. Mean relative dose intensity was high (95.7%, 95%) CI: 91.7-99.7) and had no correlation with treatment outcome. The MACOP-B and VACOP-B combination chemotherapy regimens were found to be effective and minimally toxic for young patients up to 55 years old with intermediate-grade NHL.

Adolescent↗

PubMed1998

Fast-FISH detection and semi-automated image analysis of numerical chromosome aberrations in hematological malignancies.

A new fluorescence in situ hybridization (FISH) technique called Fast-FISH in combination with semi-automated image analysis was applied to detect numerical aberrations of chromosomes 8 and 12 in interphase nuclei of peripheral blood lymphocytes and bone marrow cells from patients with acute myelogenous leukemia (AML) and chronic lymphocytic leukemia (CLL). Commercially available alpha-satellite DNA probes specific for the centromere regions of chromosome 8 and chromosome 12, respectively, were used. After application of the Fast-FISH protocol, and microscopic images of the fluorescence-labelled cell nuclei were recorded by the true color CCD camera Kappa CF 15 MC and evaluated quantitatively by computer analysis on a PC. These results were compared to results obtained from the same type of specimens using the same analysis system but with a standard FISH protocol. In addition, automated spot counting after both FISH techniques was compared to visual spot counting after standard FISH. A total number of about 3,000 cell nuclei was evaluated. For quantitative brightness parameters, a good correlation between standard FISH labelling and Fast-FISH was found. Automated spot counting after Fast-FISH coincided within a few percent to automated and visual spot counting after standard FISH. The examples shown indicate the reliability and reproducibility of Fast-FISH and its potential for automatized interphase cell diagnostics of numerical chromosome aberrations. Since the Fast-FISH technique requires a hybridization time as low as 1/20 of established standard FISH techniques, omitting most of the time consuming working steps in the protocol, it may contribute considerably to clinical diagnostics. This may especially be interesting in cases where an accurate result is required within a few hours.

Aneuploidy↗

PubMed1998

Thrombotic thrombocytopenic purpura complicating chronic myelogenous leukemia treated with interferon-alpha. A report of two successfully treated patients.

Two patients with chronic myelogenous leukemia are described in whom thrombotic thrombocytopenic purpura (TTP) developed following treatment by interferon-alpha. In one of the patients, a lymphoblastic transformation was diagnosed concomitantly. Prompt institution of plasmapheresis, steroids and vincristine resulted in complete resolution. In the hitherto reported case of TTP complicating interferon-alpha treated chronic myelogenous leukemia, the course was fatal.

Antineoplastic Agents↗