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R Berger

Publications and source records attributed to R Berger.

At least 523 records · Page 29Linked to original sources
PubMed1990

All-trans retinoic acid as a differentiation therapy for acute promyelocytic leukemia. I. Clinical results.

Twenty-two patients with acute promyelocytic leukemia were treated with all-trans retinoic acid (RA, 45 mg/m2 per day) for 90 days. Of the 22, four patients were previously untreated, two were resistant after conventional chemotherapy, and 16 were in first (n = 11), second (n = 4), or third (n = 1) relapse. We observed 14 complete response, four transient responses, one failure, and three early deaths. Length of hospitalization and number of transfusions were notably reduced in complete responders. Correction of coagulation disorders and an increase of WBCs were the first signs of all-trans RA efficacy. Morphologic analysis performed at days 0, 15, 30, 45, 60, and 90 showed that complete remissions were obtained without bone marrow (BM) hypoplasia. Presence of Auer rods in the maturing cells confirmed the differentiation effect of the treatment. At remission, the t(15;17) initially present in 20 patients was not found. The in vitro studies showed a differentiation in the presence of all-trans RA in 16 of the 18 tested cases. The single nonresponder to all trans RA in vitro did not respond in vivo. Adverse effects of RA therapy--skin and mucosa dryness, hypertriglyceridemia, and increase of hepatic transaminases--were frequently noted. We also observed bone pain in 11 patients and hyperleukocytosis in four patients. Whether maintenance treatment consisted of low-dose chemotherapy or all-trans RA, early relapses were observed. Five patients are still in complete remission (CR) at 4 to 13 months. Our study confirms the major efficacy of all-trans RA in M3, even in relapsing patients. Remissions are obtained by a differentiation process.

Adult↗
PubMed1990

Stable isotope dilution analysis of cystine in granulocyte suspensions as cysteine: a powerful method for the diagnosis, the follow-up, and treatment of patients with cystinosis.

A stable isotope dilution method was developed for the determination of cystine in granulocytes. Granulocytes were isolated from blood samples of treated cystinosis patients. Cystine in the granulocyte suspension was decoupled from proteins and converted to cysteine by treatment with a tri-butyl phosphine solution. Tertiary butyldimethyl silyl derivatives were prepared and analyzed by gas chromatography/mass spectrometry. Selective ion monitoring was carried out at m/z 304.3 (M-159 and m/z 406.4 (M-57) for the natural, and at m/z 306.3 and 408.4 for the labelled compound. [3,3,3',3'-2H]-DL-cystine was used as internal standard for the isotope dilution analysis. Concentrations of cystine in granulocytes could be accurately measured. There was a distinct difference in cystine concentrations in healthy individuals and treated patients.

Adolescent↗
PubMed1990

Chromosomal deletions in non-Hodgkin's malignant lymphomas.

The cytogenetics of 151 non-Hodgkin's malignant lymphomas (NHL) was reviewed to assess the incidence of monosomies and partial deletions. The incidence of complete or partial loss of chromosomes, possibly indicating putative tumor suppressor genes, was not significant. For chromosomes 3, 11, 13, 17, and 22, these frequencies were respectively 0%, 6.6%, 5.3%, 5.2%, and 6.6%. No specific association of deletions could be established. Three patients had a rearrangement of band 1q21 associated with deletion of chromosome 13. Finally, the most frequent chromosome segment loss in NHL involves the long arm of chromosome 6 (15.2%).

Chromosome Deletion↗
PubMed1990

Two distinct mechanisms for the SCL gene activation in the t(1;14) translocation of T-cell leukemias.

Molecular study of a t(1;14)(p32;q11) translocation found in an acute T-cell leukemia (Kd cells) with a relatively mature phenotype is reported. Complex DNA rearrangements were characterized in the TCR alpha/delta locus. Besides a productive V alpha/J alpha assembly found on the normal allele, two deletions within the J alpha cluster were identified in the translocated allele. The translocation breakpoints involved the TCR delta gene on chromosome 14 and the SCL locus on chromosome band Ip32 that was recently shown to be activated by the t(1;14) translocation of the DU 528 leukemic cell line. Significantly, both Kd and DU 528 translocation breakpoints were located at the boundaries of D delta or J delta segments and were clustered in a 10 kb genomic fragment of the SCL gene. The presence of recombination signal motifs (heptamer-12/23 bp spacer-nonamer) on both normal chromosome partners, and N nucleotide addition on both derivative chromosomes involved the recombinase system in the translocation event. The SCL locus was highly expressed as a 5 kb transcript in Kd cells and, as already reported, as a 2 kb transcript in DU 528 cells. Importantly, a 5 kb SCL transcript was also detected in immature nonlymphoid hematopoietic cells but not in normal mature T cells, suggesting that it might correspond to the normal SCL transcript. Taken together, our data support the notion that the involvement of the SCL gene in the leukemogenic process may occur through overexpression of an apparently normal transcript (Kd cells) or expression of a truncated RNA (DU 528 cells).

Amino Acid Sequence↗
PubMed1990

New localizations of VH sequences by in situ hybridization with biotinylated probes.

The chromosomal localization of genes of three VH families (VH 1-3) was performed using in situ hybridization with biotinylated probes. Significantly strong signals were observed on chromosome 14, band 14q32, and on bands 16p11 and 15q11, although less frequently. Signal intensity and frequency were more important on chromosome 14 with all three probes, and on chromosome 16 with the VH2 and VH3 probes, while chromosome 15 was more marked than 16 with the VH1 probe. The localization of VH gene on chromosomes other than 14 suggests that several genes of the VH family had been simultaneously translocated in evolution and that the newly localized VH sequences may be pseudogenes.

Biotin↗
PubMed1990

In situ hybridization ascertains the presence of a translocation t(6;11) in an acute monocytic leukemia.

In situ hybridization was performed in a case of acute monoblastic leukemia (FAB type M5b) with a rearrangement of the long arm of chromosome 11. Cytogenetic analysis after R- and G-banding showed an apparent deletion of 11q with a breakpoint at 11q23, and a translocation t(6;11) was suspected in certain metaphases. In situ hybridization with a biotinylated cosmid probe hybridizing at 11q25 confirmed the translocation t(6;11)(q27;q23). Use of nonradioactive in situ hybridization techniques for more precise characterization of chromosomal rearrangements in malignant cells is emphasized.

Bone Marrow↗
PubMed1990

Phosphorylase b kinase deficiency in man: a review.

Phosphorylase b kinase is involved in the activation of glycogen phosphorylase and is thus involved in the breakdown of glycogen. The enzyme exists as several tissue specific isoenzymes of which the muscle enzyme (rabbit) has been most characterized. It is a multimeric protein composed of four subunits, alpha, beta, gamma and delta. The four subunits are coded on different chromosomes, the alpha, beta and gamma subunit genes being on the X, 16 and 17 chromosomes respectively. The delta subunit is a calmodulin and confers calcium sensitivity on phosphorylase b kinase. Tissue specificity of the enzyme is conferred, at least in some cases, by variation in the gamma subunit. Seven different clinical types of phosphorylase b kinase deficiency have been described. The most common type is X-linked and affects the liver only; other types affect liver, muscle and liver, muscle or heart and have an autosomal recessive mode of inheritance, while in some types the mode of inheritance is not clear. Diagnosis based on the study of erythrocytes or leukocytes can be misleading due to the tissue specific nature of the enzyme, and liver or muscle biopsies may be required.

Diagnosis↗
PubMed1990

The natural history of liver glycogenosis due to phosphorylase kinase deficiency: a longitudinal study of 41 patients.

We report a longitudinal study of 41 patients with liver glycogenosis due to phosphorylase kinase deficiency. In their youth, patients displayed hepatomegaly (92%), growth retardation (68%), delayed motor development (52%), hypercholesterolaemia (76%), hypertriglyceridaemia (70%), elevation of glutamate pyruvate transaminase (56%) and fasting hyperketosis (44%). With age, these clinical and biochemical abnormalities gradually disappeared and most adult patients were asymptomatic.

Aging↗
PubMed1990

The human genes for the alpha and gamma subunits of the mast cell receptor for immunoglobulin E are located on human chromosome band 1q23.

The receptor with high affinity for immunoglobulin E (Fc epsilon RI) is a key molecule in triggering the allergic reaction. It is a tetrameric complex of one alpha subunit, one beta subunit, and two disulfide-linked gamma subunits. This receptor is present exclusively on mast cells and basophils. Molecules identical to the gamma subunit of Fc epsilon RI also form a cell surface complex with other Fc receptors such as mouse Fc gamma RIIa in macrophages and most probably with human Fc gamma RIII (CD16) in natural killer (NK) cells. Here we show by in situ hybridization that the human genes for the alpha (FCER1A) and gamma subunits (FCER1G) of Fc epsilon RI and the gene for Fc gamma RIII (FCGR3, CD16) are located on human chromosome band 1q23.

Antigens, Differentiation, B-Lymphocyte↗
PubMed1990

Separation of different forms of S-adenosylmethionine synthetase by fast protein liquid chromatography.

A method is described by which different forms of S-adenosylmethionine synthetase are separated. The method makes use of fast protein liquid chromatography on an anion exchange hydrophilic polyether resin. Different forms of S-adenosylmethionine synthetase from rat and human liver and kidney and rat zajdela hepatoma cells can be separated within 15 min. From a mixture of rat liver and kidney cytosols all three forms alpha, beta and gamma can be separated. The time needed to separate the different forms of S-adenosylmethionine synthetase is reduced from 3 h with conventional gel filtration methods, to 15 min using this HPLC anion-exchange method. Also the amount of tissue needed to detect the different forms is reduced from 125 mg to 12.5 mg of fresh rat liver tissue. These advantages make this newly developed method applicable when large numbers of samples have to be analyzed or when only small amounts of tissue are available.

Animals↗
PubMed1990

Cytogenetic studies of 44 T-cell acute lymphoblastic leukemias.

Cytogenetic studies on 44 patients with T-cell acute lymphoblastic leukemia (ALL) were reported. The incidence of leukemia without detectable chromosomal changes was 25%. Hyperdiploidy with more than 50 chromosomes was found in only one patient. Previously described nonrandom abnormalities like 6q-, 9p-, and 12p- were observed, and it was confirmed that they are not specific for a particular type of ALL. The incidence of chromosomal rearrangements on chromosomes 7 and 14 where the T-cell receptor gene loci are located was 36% of those with abnormal karyotypes and 27% of the total. This was clearly different from the frequency of rearrangements of these bands found in T-cell lymphoma. Finally, a rearrangement on bands 11q14-q21 was detected in five cases.

Adolescent↗