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R Berger

Publications and source records attributed to R Berger.

At least 271 records · Page 15Linked to original sources
PubMed1996

An interstitial 11q23 deletion proven to be a rearrangement interrupting the MLL gene in an infant with acute myeloblastic leukemia.

Chromosome studies of an infant with acute myeloblastic leukemia (AML), classified as M2 in the FAB nomenclature revealed an unusual karyotype with del(11)(q23) and a marker chromosome resembling a small chromosomal fragment present in all metaphase cells examined. Fluorescence in situ hybridization (FISH) showed the splitting of a YAC probe containing a part of MLL between the del(11) and mar chromosomes. Painting showed that the mar chromosome contained DNA sequences from chromosome 11, but that the centromeric region was not marked by a chromosome 11-specific alphoid probe. The chromosomal breakpoint was located within the MLL gene by Southern blot experiments. The deletion of 11q was thus interstitial. This case illustrates the importance of associating cytogenetics, several FISH techniques, and molecular studies to analyze unusual karyotypes in leukemia.

Chromosome Aberrations↗
PubMed1996

Maryland women living with HIV/AIDS.

Approximately one-quarter of the acquired immunodeficiency syndrome (AIDS) cases reported in Maryland are women. African-American women account for 80% or more of the cases in the Baltimore-Metropolitan area. Human immunodeficiency virus (HIV)-positive women are frequently dealing with a constellation of social problems including lack of resources, care-taking responsibilities for extended families, histories of substance abuse, and loss of others to AIDS. This article is an attempt to describe the social context of living with HIV/AIDS to Maryland physicians.

Acquired Immunodeficiency Syndrome↗
PubMed1995

[Mumps: efficacy of booster immunization].

10 children aged 15 years, who presented with anti-mumps antibodies of < 3 PEI (Paul Ehrlich Institute) despite documented mumps vaccination in the past, were boosted with Triviraten Berna (Rubini mumps strain) and the antibody response was assessed after 7, 28 and 90 days. All 5 children boosted with the same vaccine (Rubini mumps strain) had a titer rise as early as day 7 persisting for 3 months. The 4 children primed with the Jeryl Lynn mumps strain showed a primary immune response, i.e. a rise of the antibody titer after 28 days only, which did not persist well. The child originally primed with the Urabe mumps strain did not show any significant immune response on day 28, which means a negative result. Children apparently susceptible to mumps cannot be differentiated from immune children by measurement of antibody titers. Reexposure to the homologous vaccine virus elicited a persisting immune response: however, revaccination with a heterologous vaccine virus elicited an immune response directed against different antigenic epitopes, followed by limited persistence of circulating antibodies. The efficacy of a second dose of mumps vaccine was demonstrated in 9/10 children. Only by using a two-dose immunization schedule is it possible to effectively avoid the occasionally serious complications of this viral infection, as has been achieved in Finland.

Adolescent↗
PubMed1995

High frequency of t(12;21) in childhood B-lineage acute lymphoblastic leukemia.

The recurrent t(12;21)(p12;q22) translocation fuses two genes, TEL and AML1, that have previously been shown to be independently involved in myeloid malignant proliferations. A search for rearrangement of the TEL locus in the region known to be involved in t(12;21) was performed by Southern blotting in a panel of hematopoietic malignancies. The presence of a t(12;21) was confirmed by fluorescence in situ hybridization (FISH) and/or reverse transcriptase (RT)-polymerase chain reaction (PCR). We report that fusion of TEL to AML1 is specifically observed in at least 16% of the childhood B-lineage acute lymphoblastic leukemia (ALL) investigated, none of which had been previously identified as harboring t(12;21).

Adolescent↗
PubMed1995

Direct measurement of lipid peroxidation in submitochondrial particles.

The susceptibility of the polyunsaturated fatty acid parinaric acid (cis-PnA) to peroxidative damage with concomitant loss of its fluorescent character can be used to detect lipid peroxidation in a direct and sensitive way. The procedure, originally developed to measure peroxidation in lipid vesicles and erythrocyte membranes, has been adapted for the study of submitochondrial particles. Optimal conditions for the concentrations of cis-PnA (0.8 mol %), mitochondrial membrane (100 microM membrane phospholipid), and the radical generating system (50 microM NADH and 10 microM:1 mM Fe(III)-ADP) were established. In the absence of peroxidation inducing compounds, a stable fluorescent signal can be detected. Upon addition of NAD(P)H and ADP-Fe(III), lipid peroxidation starts, and the observed fluorescence decrease is a measure of peroxidation. Both NADH and NADPH were able to induce lipid peroxidation in submitochondrial particles in the presence of an iron chelate. The use of NADH resulted in higher rates of peroxidation compared with NADPH at the same concentration. Whereas the rate of NADH-induced lipid peroxidation was maximal at very low NADH concentrations (2.5 microM) and decreased when the concentration became higher, the NADPH-induced lipid peroxidation reaches saturation at 100 microM. NADH-induced lipid peroxidation in submitochondrial particles from different rat tissues (heart, skeletal muscle, and liver) resulted in a clear difference in peroxidation rates. The highest rates were observed in heart submitochondrial particles, while the lowest rates were obtained in submitochondrial particles derived from liver. Skeletal muscle submitochondrial particles showed intermediate rates of lipid peroxidation.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenosine Diphosphate↗
PubMed1995

Bridging Ral GTPase to Rho pathways. RLIP76, a Ral effector with CDC42/Rac GTPase-activating protein activity.

Ra1A and Ra1B are GTPases of unknown function and are activated by proteins, Ra1GDS, that interact with the active form of another GTPase, Ras. To elucidate Ral function, we have searched for proteins interacting with an activated form of Ra1A using the two-hybrid method and a Jurkat cell library. We have identified a partial cDNA encoding a protein, RLIP1, which binds to activated Ra1A and this binding requires an intact effector domain of Ra1A. Biochemical data with purified Ra1A confirm the genetic results. This protein also bears a region of homology with GTPase-activating protein (GAP) domains that are involved in the regulation of GTPases of the Rho family and, indeed, RLIP1 displays a GAP activity acting upon Rac1 and CDC42, but not RhoA. This GAP region is not required for RLIP1 binding to Ra1. The whole cDNA was cloned, and it encodes a 76-kDa polypeptide, RLIP76, which also binds RalA. The Rho pathway is involved in membrane and cytoskeleton modifications after mitogenic stimulation and acts in parallel to and synergistically with the Ras pathway. We propose that these pathways are linked through a cascade composed of Ras --> Ra1GDS --> Ra1 --> RLIP76 --> CDC42/Rac1/Rho, allowing modulation of the Rho pathway by the Ras pathway.

ATP-Binding Cassette Transporters↗
PubMed1995

Cloning of a new member of the insulin gene superfamily (INSL4) expressed in human placenta.

A new member of the insulin gene superfamily was identified by screening a subtracted cDNA library of first-trimester human placenta and, hence, was tentatively named early placenta insulin-like peptide (EPIL). In this paper, we report the cloning and sequencing of the EPIL cDNA and the EPIL gene (INSL4). Comparison of the deduced amino acid sequence of the early placenta insulin-like peptide revealed significant overall and structural homologies with members of the insulin-like hormone superfamily. Moreover, the organization of the early placenta insulin-like gene, which is composed of two exons and one intron, is similar to that of insulin and relaxin. By in situ hybridization, the INSL4 gene was assigned to band p24 of the short arm of chromosome 9. RT-PCR analysis of EPIL tissue distribution revealed that its transcripts are expressed in the placenta and uterus.

Amino Acid Sequence↗
PubMed1995

The t(10;11) translocation in acute myeloid leukemia (M5) consistently fuses the leucine zipper motif of AF10 onto the HRX gene.

The gene on chromosome 10 at band p12 (AF10), involved in the t(10;11) translocation in acute myeloid leukemia, has been identified and shown to contain conserved zinc finger and leucine zipper domains. These regions are highly homologous to the equivalent regions on AF17, the gene involved in the t(11;17) translocations. A series of adult, childhood, and infant leukemias with either simple or complex versions of the t(10;11) has been examined by Southern analysis and shown to involve rearrangement to the HRX locus. Reverse transcriptase-polymerase chain reaction from either bone marrow or peripheral blood cells showed that HRX sequence was fused to AF10 sequence in all 8 cases and subsequent sequence analysis showed an in-frame fusion between the HRX and AF10 sequence. A consistent feature of these fusions was the juxtaposition of the leucine dimerization motif of AF10 onto the NH2-terminal region of HRX. The published data suggest that a similar conclusion can be drawn about the t(11;17) translocation, implying a critical role for this motif in the chimaeric HRX protein.

Adult↗
PubMed1995

A new type of p16INK4/MTS1 gene transcript expressed in B-cell malignancies.

Chromosome band 9p21-22 is frequently altered by nonrandom abnormalities, mainly deletions, in hemopoietic malignancies of the lymphoid lineage. We have analysed a translocation t(9;14)(p21-p22;q11) in a B-cell type acute lymphoblastic leukemia. Location of the 14q11 breakpoint within the TCR-alpha/delta locus allowed the isolation of a fusion transcript composed of a 3' segment containing part of the constant region of the TCR-alpha gene and a 5' segment from chromosome 9, designated 0.18. This 0.18 segment was also part of cDNAs isolated from two tumoral B-cell lines (RPMI-8226, Raji). In both cases, 0.18 was juxtaposed 5' to a sequence corresponding to exons 2 and 3 of the p16INK4/MTS1 gene which is located on band 9p21-22. Unexpectedly, none of the two ATG codons found in 0.18 was in phase with that of the exons 2 and 3 of p16INK4/MTS1. Furthermore, in vitro translation product of a RPMI-8226 cDNA clone generated a product that was not immunoprecipitated by antibodies specific of the C-terminal end of the p16INK4/MTS1 protein. Evidence for similar transcripts in non tumoral lymphoid B cells (unstimulated peripheral blood lymphocytes (PBL) and lymphoblastoid cell lines) were obtained by using amplimers representative of the 0.18 segment and the p16INK4/MTS1 exon 2. Altogether, these data are consistent with the existence of a new type of p16INK4/MTS1 transcript whose significance is discussed.

Base Sequence↗
PubMed1995

The t(12;21) of acute lymphoblastic leukemia results in a tel-AML1 gene fusion.

Analysis of a growing number of chromosomal translocations in human tumors have shown that they frequently result in gene fusions encoding chimeric proteins. We have characterized the recurrent t(12;21)(p12;q22) translocation present in human B-lineage acute leukemias. This translocation fused two genes, tel and AML1, that have previously been described in chromosomal translocations specific for myeloid malignancies. These two genes therefore belong to an increasing number of human genes that are involved in a variety of hematopoietic malignant disorders and can be rearranged with numerous partners. Interestingly, in these acute leukemias, deletion of the other tel allele from the normal chromosome 12 was associated with the tel rearrangement, whereas both tel alleles were present in the chronic leukemias bearing a t(5;12) that we have tested.

Adolescent↗
PubMed1995

[Toxoplasmosis and pregnancy--findings from umbilical cord blood screening in 30,000 newborn infants].

Cord blood screening for congenital toxoplasmosis was performed prospectively on 30,000 samples collected between 1986 and 1994 in the region of Basel, Switzerland, covering up to 95% of all births. Congenital infection was suspected in cases of serum with specific antitoxoplasma IgM or IgA or with a level of specific IgG above 300 IU/ml as measured by EIA from Sanofi-Pasteur. The percentage of cases to be screened declined from 2.5 to 1.2% and the cases of confirmed congenital toxoplasmosis from 0.073 to 0.033% during the observation period. This observation may be due to several reasons, such as improved primary prevention or more frequent diagnosis and treatment during pregnancy. In 178 cases of cord blood serology suspicious for acute toxoplasmosis, an enquiry with the gynecologist in charge of the pregnant woman was carried out. 126 mothers (71%) presented with a confirmed immunity against Toxoplasma gondii early in pregnancy and screening of the child was not needed. From 37 pregnancies (21%) no information was available. 15 out of 24 confirmed cases of toxoplasmosis of the mother during pregnancy were detected by cord blood analysis. In 17 of 24 cases of maternal toxoplasmosis treatment with spiramycin, pyrimethamine/sulfadoxine or both was performed. 10 of 17 newborns from mothers treated during pregnancy had elevated toxoplasma IgG titres at birth, but only one child was infected. 7 newborns had an inconspicuous toxoplasma serology at birth and were not infected. 7 cases of toxoplasmosis during pregnancy were detected by the check back and remained untreated; 4 out of 7 newborns had congenital toxoplasmosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Antibodies, Protozoan↗
PubMed1995

Localization of TDPX1, a human homologue of the yeast thioredoxin-dependent peroxide reductase gene (TPX), to chromosome 13q12.

Reactive oxygen species and free radicals that are produced during normal metabolism can potentially damage cellular macromolecules. Defenses against such damage include a number of antioxidant enzymes that specifically target the removal or dismutation of the reactive agent. We report here the isolation and regional mapping of a human gene, TDPX1, that encodes an enzyme homologous to a yeast thioredoxin-dependent peroxide reductase (thioredoxin peroxidase, TPX). The human TDPX1 coding sequence was determined from the product of a polymerase chain reaction (PCR) amplification of human cDNA. Based on PCR analysis of DNA from a human/rodent somatic cell hybrid panel, the TDPX1 locus was assigned to chromosome 13. Further localization of the locus to 13q12 was accomplished by fluorescence in situ hybridization analysis, using as a probe DNA from a yeast artificial chromosome (YAC) that contains the TDPX1 gene. It was also determined by PCR analysis of various YACs that the TDPX1 locus is in the region of the dinucleotide repeat markers D13S289 and D13S290. This regional mapping localizes the TDPX1 gene to a genomic region recently shown to contain the breast cancer susceptibility gene BRCA2 and a gene associated with a form of muscular dystrophy. Oxygen radical metabolism has been hypothesized to be important for cancer, muscular dystrophy, and other disorders, so TDPX1 should be considered a candidate gene for these diseases.

Amino Acid Sequence↗
PubMed1995

A new congenital dysmegakaryopoietic thrombocytopenia (Paris-Trousseau) associated with giant platelet alpha-granules and chromosome 11 deletion at 11q23.

This study characterizes a new congenital thrombocytopenia with mild hemorrhagic tendency occurring in a woman and her child with the following features. We found a deletion of the distal part of one chromosome 11 [del(11)q23.3-->qter] that was detected by cytogenetic analysis and confirmed by chromosome painting in the two patients and also an increased number of bone marrow megakaryocytes (MKs), including numerous micromegakaryocytes (mMKs) associated with a normal platelet life span. A normal number of MK colonies in culture was observed with one third of them containing a few large MKs; however, these were always associated with mMKs identified by immunologic staining. A massive cell lysis was observed at the end of the maturation. Fifteen percent of the platelets in the peripheral blood showed giant alpha-granules resulting from the fusion of alpha-granules. These giant granules, which appeared in red on giemsa stain, had a mean diameter of 1.5 microns and showed all markers (detected at electron microscopy by immunogold method) of matrix and alpha-granule membrane, ie, von Willebrand factor, fibrinogen, CD41, CD62P (P-selectin); however, they differed from lysosomes because acid phosphatases were not present. These giant alpha-granules were unable to release their contents after stimulation by thrombin, in contrast to platelets with normal morphology. Abnormalities in bone marrow MK maturation that were detected at the electron microscopic level and that led to lysis of numerous MKs were responsible for thrombocytopenia and were similar in both patients. MK abnormalities are probably the consequence of the chromosome aberration. ETS 1 and FLI, two proto-oncogenes that appear to be essential with GATA1 for the normal expression of MK-specific genes, map to 11q23-q24 and are, thus, deleted in this thrombocytopenia. In conclusion, the association of all these abnormalities constitutes a new familial platelet disorder and may present a valuable model for exploring the role of some genes involved in the regulation of thrombopoiesis.

Adult↗
PubMed1995

Traditional healers.

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Acquired Immunodeficiency Syndrome↗
PubMed1995

A novel class of zinc finger/leucine zipper genes identified from the molecular cloning of the t(10;11) translocation in acute leukemia.

A novel class of conserved transcription factors has been identified from the molecular cloning of AF10, the gene involved in the t(10;11)(p12;q23) translocation of acute myeloid leukemias. AF10 encodes a 109-kD protein of 1,027 amino acids and contains an N-terminal zinc finger region and a C-terminal leucine zipper. These structures have been found to be conserved in sequence and position in three other proteins, AF17, BR140, and a previously unrecognized Caenorhabditis elegans gene, provisionally named CEZF. The overall structure, level of sequence conservation, and expression pattern suggest that these genes encode a new class of transcription factors, some of which are targets for chromosomal translocation in acute leukemia.

Adaptor Proteins, Signal Transducing↗
PubMed1995

Inversion-associated translocations in acute myelomonocytic leukemia with eosinophilia.

Cytogenetic studies of three acute myelomonocytic leukemias with bone marrow eosinophilia (M4EO) revealed chromosome 16 inversion associated with additional abnormalities. The inverted chromosome 16 was involved in two patients. Fluorescence in situ hybridization (FISH) experiments with a YAC probe detecting inv(16) showed that the translocation breakpoints involving chromosome 16 did not implicate the inversion breakpoints. FISH can thus distinguish between true variant translocations and translocations with other breakpoints on chromosome 16 in M4EO.

Adult↗
PubMed1995

Molecular basis of 11q23 rearrangements in hematopoietic malignant proliferations.

Chromosomal abnormalities of the 11q23 band occur frequently in various hematopoietic malignant disorders. Because numerous partner chromosomes have been previously described, it is now important to determine the number of genes involved at 11q23 and to clarify the role of the partner genes. Recent efforts in several laboratories have identified a trithorax-related gene that is involved in most of the 11q23 abnormalities. The aim of this review is to summarize the recent data concerning these 11q23 rearrangements and the understanding of their consequences.

Base Sequence↗