PubMed Health⌕ Search

Biomedical subjects

D Rund

Publications and source records attributed to D Rund.

At least 37 records · Page 2Linked to original sources
PubMed1997

De novo acute myeloid leukemia with near-pentaploidy: diploid karyotype and lymphoblastic phenotype at relapse.

Hyperploidy is a rare finding in leukemias, with isolated cases of tetraploidy reported in acute myeloblastic and acute lymphblastic leukemias. We report the first case of acute myeloid leukemia with near-pentaploidy (5 n+/-) which was present in 100% of metaphases at diagnosis. By light microscopy, the leukemic blasts were exceptionally large and coarsely granulated. Following one cycle of induction chemotherapy, complete morphologic and cytogenetic remission was documented. Four weeks later relapse occured, at which time the karyotype was diploid and the morphological and immunophenotypic characteristics were those of a lymphoid leukemia. However, the presence of three aberrant chromosomes (5q+, 6q+ and 20q+) confirmed that this was clonal evolution of the original myeloid leukemia. To the best of our knowledge, this case represents the first report of near-pentaloidy in de novo, pretreatment human leukemia.

Acute Disease↗
PubMed1996

Microsatellite instability and p53 mutations in therapy-related leukemia suggest mutator phenotype.

During the last decade the frequency of therapy-related acute leukemia (t-leuk) and myelodysplastic syndrome (t-MDS) has been increasingly observed. Over the past 15 years, we treated 56 patients with t-leuk who had received prior chemotherapy (39%), radiotherapy (11%), or both (45%). The drugs received included alkylating agents and topoisomerase II inhibitors. The primary tumors included hematological malignancies (49%) and solid tumors such as breast or ovarian cancer. The median age at diagnosis of the primary tumor was relatively young (43 years +/- 18). Twelve patients had more than one primary tumor and 31 patients had a family history of malignancy. Karyotypic abnormalities were found in 91% of the patients. Prognosis was uniformly poor, with an overall median survival of 10 months. Twelve of the 18 patients examined (67%) had a multidrug resistance phenotype. P53 genes of the leukemic cells, as well as the original tumors, were analyzed in 21 patients using polymerase chain reaction (PCR) with single-stranded conformation polymorphism analysis followed by sequencing. P53 mutations were identified in 38% of these patients, a relatively high prevalence compared with other forms of MDS or de novo acute myeloid leukemia. Mutations were nongermline and restricted to the leukemic cells. We identified different p53 mutations in the various primary tumors of individual patients. The presence of a mutator phenotype was assessed by PCR analysis of microsatellites in eight loci (one trinucleotide repeat sequence, four dinucleotide, and three mononuclear repeat sequences). Microsatellite instability in two to seven loci were found in 15 of 16 (94%) of the patients. This instability is compatible with a mutator phenotype, which predisposes the patients to the development of malignancies including t-leuk.

Adult↗
PubMed1996

Selective discharge of patients with acute myeloid leukemia during chemotherapy-induced neutropenia.

PURPOSE: It is common practice for patients with acute myeloid leukemia (AML) to be observed in hospital during the entire nadir after intensive chemotherapy. In an attempt to lessen the likelihood of developing infections with hospital acquired pathogens, we usually discharge patients upon completion of chemotherapy and follow them as outpatients. They are readmitted if fever develops. We evaluated the feasibility and safety of this practice. PATIENTS AND METHODS: We studied 29 patients with AML (median age 40 years, range 16-63) who were treated with intensive remission-induction and consolidation chemotherapy. Afebrile patients not receiving antibiotics were discharged immediately following chemotherapy and were followed every 3-4 days at the day care unit. Patients were instructed to return immediately if fever rose to 38.2 degrees C or a fever of 38 degrees C persisted for 2 hr. The 29 patients received a total of 86 courses. Following 50 courses, patients were discharged. These 50 ambulatory nadir periods (ANPs) were monitored. RESULTS: Median WBC and platelet counts on discharge were 2,900 per cubic millimeter (range 300-8,300) and 137,000 per cubic millimeter (range 17,000-618,000), respectively. Mean traveling time from the hospital by car was 1.6 hr (range 15 min-3 hr). In three of the 50 ANPs (6%), patients were not readmitted during their entire nadir. During 47 of the ANPs, patients returned to the hospital (because of fever in 44 cases), a mean of 7.2 days (range 1.0-12.7 days) after discharge. In 45 ANPs, patients were readmitted in good general condition. Four patients had life-threatening complications. Two patients were admitted in septic shock due to delay in seeking admission, but rapidly recovered. Two other patients died, one of cardiogenic shock within 24 hr of readmission and one 24 days later. Only one of the 11 gram negative bacteria cultured was resistant to mezlocillin and gentamicin. After 45 ANPs, patients were discharged a mean of 12.2 days (range 5-42 days) following readmission. We estimate that approximately 383 hospital days were saved by this policy, a mean of 7.6 days per patient, representing 16% of total inpatient hospital days. CONCLUSIONS: For AML patients who are reliable and without complicating medical conditions, selected discharge following chemotherapy is a low-risk practice and may reduce the incidence of infection with resistant hospital-acquired pathogens.

Acute Disease↗
PubMed1995

Thalassemia major 1995: older patients, new therapies.

There have been many advances in supportive treatment used for beta-thalassemia major. Survival has increased substantially, and an increasing number of patients reach adolescence and adulthood. These older patients present new clinical challenges. Complications of transfusion, most commonly hepatitis C, are still a cause of mortality and morbidity. The achievement of optimal growth and development, including fertility, is an important goal of conservative management. Long-term survival has also been achieved with bone marrow transplantation. Assessment of growth, development and iron balance in the years after transplantation reveals residual problems requiring treatment despite cure of thalassemia. New therapies of beta-thalassemia are still being developed, both supportive and curative in nature. Supportive care improvements include oral chelation and methods to increase HbF production. Advances in curative modalities include use of new sources of stem cells, such as cord blood and fetal liver. In the future, gene therapy may allow for cure of the older patient without the mortality and morbidity of allogenic transplantation. Treatment of thalassemia major requires consideration of the available therapeutic options for each patient, and the risk/benefit ratio of a supportive versus curative approach.

Age Factors↗
PubMed1995

Severe migratory polyarthritis following in vivo CAMPATH-1G.

CAMPATH-1G is an IgG2b rat antihuman (CDw52) monoclonal antibody (MoAb) which is currently being used for T cell depletion in the setting of allogeneic bone marrow transplantation (BMT). In addition it elicits substantial lymphoid depletion, an effect which is being explored for remission induction in patients with lymphoid malignancies and for treating patients with various autoimmune disorders, in particular rheumatoid arthritis. Recently, in vivo CAMPATH-1G has been introduced to achieve increased immunosuppression in the pretransplant conditioning, for prevention of graft rejection following T cell depleted BMT. Here we describe a patient with T cell lymphoblastic lymphoma who received in vivo CAMPATH-1G as part of the pretransplant conditioning regimen and who, 6 days after the first dose, developed severe migratory polyarthritis. This is the first report of severe migratory polyarthritis as a very unusual complication following CAMPATH-1G MoAb administration.

Adult↗
PubMed1994

Severe thalassaemia intermedia caused by interaction of homozygosity for alpha-globin gene triplication with heterozygosity for beta zero-thalassaemia.

A 3-year-old child was evaluated for beta-thalassaemia intermedia. Molecular characterization including beta-globin gene sequence analysis revealed heterozygosity for a single beta-thalassaemia mutation, IVSI nt1 (G-->A). In addition the patient was found to be homozygous for alpha-globin gene triplication (alpha alpha alpha anti3.7/alpha alpha alpah anti3.7). The propositus has a significantly more severe phenotype than has been previously reported with this combination of genetic defects. In contrast, four individuals heterozygous for both triplicated alpha and for beta thalassaemia had a phenotype of thalassaemia minor, and a fifth had very mild thalassaemia intermedia.

Blotting, Southern↗
PubMed1993

G6PD Mediterranean accounts for the high prevalence of G6PD deficiency in Kurdish Jews.

The Jews of Kurdistan are a small inbred population with a high incidence of beta-thalassaemia and glucose-6-phosphate dehydrogenase (G6PD) deficiency. Recently, it was reported that the beta-thalassaemia in this population shows an unusual mutational diversity; 13 different mutations were identified, of which 4 had not previously been observed in any other population. In contrast, we now report that the G6PD deficiency, which has the highest known incidence in the world, and which affects about 70% of males, is almost entirely attributable to a single widespread mutation, G6PD Mediterranean.

Female↗
PubMed1993

Silent carrier beta-thalassaemia due to a severe beta-globin mutation interacting with other genetic elements.

Beta-thalassaemia is caused by the presence of two mutated beta-globin genes, one inherited from each parent. We describe two families in which the diagnosis of beta-thalassaemia intermedia was delayed because one of the parents, an obligatory heterozygote, had normal haematological parameters (silent carrier beta-thalassaemia). DNA analysis revealed that these silent carriers were heterozygous for a point mutation in the polyadenylation signal (AATAAA-AATAAG). This defect is known to cause a moderately severe beta-thalassaemia phenotype. In one case, concurrent deletional alpha-thalassaemia was found in the silent carrier, which may have contributed to the mild phenotype. The increasing availability of DNA analysis should allow prompt diagnosis of such cases. Silent carrier beta-thalassaemia presents a diagnostic challenge to the clinician who evaluates children with anaemia.

Base Sequence↗
PubMed1992

Two mutations in the beta-globin polyadenylylation signal reveal extended transcripts and new RNA polyadenylylation sites.

Two mutations in the beta-globin poly(A) signal were identified in Israeli patients with beta +-thalassemia by sequence analysis following PCR. One is a point mutation (AATAAA----AATAAG) and the other is a 5-base-pair deletion (AATAAA----A----). The mutant genes were used to investigate the function of the poly(A) signal in vivo and to evaluate the mechanism whereby these mutations lead to a thalassemic phenotype. Analysis of RNA derived from peripheral blood demonstrated the presence of elongated RNA species in patients carrying either mutation. Other aspects of RNA processing (initiation, splicing) were unimpaired. RNA obtained from the patients carrying the point mutation contained four discrete, extended RNA species, 1500-2900 nucleotides long, which were found to be polyadenylated. Some normal cleavage-polyadenylylation was also observed. The 5-base-pair deletion completely abolished cleavage at the normal site. This deletion mutation resulted in a phenotype of beta +-thalassemia, thus providing evidence that the extended mRNAs are translatable in vivo. Furthermore, additional transcripts, greater than 5 kilobases, presumably mRNA precursors, were found in all RNA samples, including those of nonthalassemic controls. The extended transcripts of the poly(A) mutants, together with the high molecular weight precursors, suggest that the human beta-globin gene transcription unit is significantly longer than previously recognized.

Base Sequence↗
PubMed1992

Mean corpuscular volume of heterozygotes for beta-thalassemia correlates with the severity of mutations.

The relationship between the degree of microcytosis and the type of mutation carried by beta-thalassemia heterozygotes was investigated. In 113 individuals, 18 different mutations were identified, correlated with mean corpuscular volume (MCV) values, and analyzed statistically. Overall, there was a wide range of MCV (56.3-87.3 fL). In almost all cases, carriers of beta(0) mutations had an MCV below 67 fL, whereas all but a few beta(+) heterozygotes had MCVs above this cutpoint. Mean MCV of beta(0) carriers was statistically significantly lower than those of beta(+) heterozygotes. The various beta(+) mutations were associated with significant differences in mean MCV values. In contrast, all the beta(0) (null) mutations had virtually identical ranges of MCV. The results indicate that degree of reduction in MCV is directly related to the severity of the mutation. Deviations, in four cases, were associated with concurrent alpha gene rearrangements, whereas in three other cases, the MCV was not significantly affected by concurrent alpha rearrangements. The MCV of beta-thalassemia heterozygotes is a valuable parameter in planning strategies for rapid identification of mutations in populations with great mutational diversity. Its use can be particularly advantageous in the setting of prenatal diagnosis. The pattern of mean corpuscular hemoglobin (MCH) values was similar to the MCV pattern. However, our results suggest that MCH may be preferred for carrier detection in population screening.

Erythrocyte Indices↗
PubMed1991

[Prenatal diagnosis of thalassemia: identification of mutations in conjunction with gene amplification in vitro].

Prenatal diagnosis of thalassemia and sickle cell anemia using DNA analysis has been performed in Israel since 1982. Until recently the tests involved analysis of polymorphic markers linked to the beta-globulin gene (RFLP). This method is not suitable for many of the families at risk. The recently developed technique of gene amplification in vitro (PCR) facilitates direct identification of the genetic lesions (mutations) using minimal amounts of DNA. The diagnosis is rapid, reliable and unambiguous and can be made early in pregnancy. Our experience in prenatal diagnosis during the past year is reported. Of 14 diagnoses, 13 were made by direct identification of mutations following PCR.

Female↗