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L Bardella

Publications and source records attributed to L Bardella.

28 records · Page 2Linked to original sources
PubMed1986

The contribution of molecular biology in the diagnosis of human lymphomas.

The relationship between T cell receptor (TCR) beta and gene immunoglobulin heavy chain locus was investigated in 25 cases of unselected human lymphomas as well as in normal and non-neoplastic lymphoid tissues. Hybridizing our blots with Jurkat 2, a clone specific for the beta chain gene of TCR, did not demonstrate extra bands in non-neoplastic tissues composed of 50-95% T-cells. On the contrary, rearranged bands were detected in six out of six cases of T-cell lymphomas. No TCR beta gene rearrangements were detected in 11 B-cell lymphomas, which in turn presented modification of the immunoglobulin heavy chain gene germline configuration. Our results suggest that TCR beta chain gene rearrangements are a good marker for human T-cell neoplasias in humans and complement the analysis with immunoglobulin genes probes. Eighth samples were devoid of any rearrangements: this group comprises cases of Hodgkin's disease T-lymphoblastic lymphomas in clinical remission and malignancies of unknown origin, as discussed in the text. We conclude that the analysis using DNA probes specific for TCR beta and IgH genes can be of aid to the pathologist in the diagnosis and classification of human lymphomas.

DNA, Neoplasm↗
PubMed1985

Multiple mechanisms of iron-induced ferritin synthesis in HeLa cells.

Iron administration to HeLa cells stimulates the accumulation of H-subunit and L-subunit rich isoferritins at similar extent. The increase in both types of isoferritins is accompanied by an increase in the amount of messenger RNAs specific for H and L subunits. The increase in the amount of these messenger RNAs, which occurs in the nucleus as well as in the cytoplasm, is proportionately lower than the increase in the protein. These results, together with analysis of transcription in isolated nuclei indicate the existence of a mechanism of transcriptional control of ferritin synthesis, associated to the translational control described so far.

Cell Nucleus↗
PubMed1984

Mechanism of enhanced RNA synthesis in acute-phase rat liver and its relationship to chromatin structure.

Nuclei isolated from the liver of rats undergoing an acute inflammatory reaction induced by turpentine treatment show increased RNA synthesis. This increase is essentially determined by a faster polyribonucleotide-elongation rate while the number of transcribing polymerase molecules is unchanged. The sensitivity of chromatin to micrococcal-nuclease digestion and the composition of chromosomal proteins are not affected by the acute-phase process. Therefore the increased RNA synthesis by liver nuclei from acutely inflamed rats does not seem to correlate with major changes in chromatin structure.

Animals↗
PubMed1982

eIF-2 initiation factor activity in Yoshida ascites hepatoma AH 130 cells and in 4-dimethylaminoazobenzene-induced liver tumor tissue during growth.

Eukaryotic initiation factor 2 (eIF-2) preparations from mid-log and plateau-phase Yoshida ascites hepatoma AH 130 cells, from the liver of Yoshida ascites tumor-bearing rats and from 4-dimethylaminoazobenzene (DAB)-induced liver tumor tissue were assayed for ternary complex formation with 3H-met-tRNAf and GTP on nitrocellulose filters. The eIF-2 factor was extracted from postnuclear homogenate supernatants by high-salt wash and purified by ion exchange chromatography on DEAE-cellulose and phosphocellulose. The results here reported demonstrate changes of 3H-met-tRNAf X eIF-2 X GTP ternary complex formation under the conditions studied. Higher rates of ternary complex formation are present in control rat liver and in DAB-induced liver tumor tissue. The liver of Yoshida ascites tumor-bearing rats and the Yoshida ascites hepatoma cells show reduced rates of ternary complex formation, that are mostly evident at the plateau-phase of the intraperitoneal ascites cell growth. The present observations may be attributable to changes in the growing conditions of plateau-phase ascites cells, with accumulation in Gl phase, affecting the ability of eIF-2 to enter in the sequential assembly of the eukaryotic protein synthesis initiation complex.

Animals↗
PubMedDate not supplied

Synthesis of heat shock proteins in rat liver after ischemia and hyperthermia.

Ischemia of rat liver is followed by recovery or cell death. Since heat shock proteins may be essential to cell survival under stress, we determined levels of heat shock proteins in liver after different periods of blood deprivation and correlated the results with cellular recovery. Cell-free synthesis by poly (A+)-mRNA and polysomes revealed 70 and 89 kd proteins which appear similar to proteins produced by the liver of rats with amphetamine-induced hyperthermia. The 70 and 89 kd proteins increased in the liver of rats which recovered from ischemia.

Animals↗
PubMedDate not supplied

Analysis of the genes for transferrin, transferrin receptor as well as H and L subunits of ferritin in idiopathic hemochromatosis.

In the attempt to define the abnormalities responsible for the severe iron overload found in patients with idiopathic hemochromatosis (IH) we analyzed, in 8 patients with IH and in 7 normal subjects, by using specific cDNA probes, the genes coding for the main iron-related proteins, i.e., transferrin, transferrin receptor, as well as H and L subunits of ferritin. In all the patients tested all the probes failed to evidentiate rearranged bands with any of the restriction enzymes employed. These findings suggest the absence of gross structural alterations of the genes examined. The lack of polymorphic sites recognized by the restriction enzymes employed in this study within or around the genes examined does not allow to associate a specific gene with the disease.

Adult↗
PubMedDate not supplied

Lack of TdT and immunoglobulin and T-cell receptor gene rearrangements in Hodgkin's disease.

To study the pathogenesis of Hodgkin's disease (HD), which today remains obscure, we have undertaken a combined experimental approach: determination of TdT and molecular analysis of rearrangements of immunoglobulin heavy chain (IgH), T-cell receptor (TCR) beta chain and the T-cell rearranging gamma (TRG) genes. TdT determination indicate would the presence of immature cells that are not detected in the normal lymphnode; molecular analysis of the rearrangements of these genes would reveal the presence of even a small monoclonal population of both T and B lineages in the lymphnodes. We believe that the combination of these two types of analysis can indicate whether an expanding lymphoid clone is responsible for this disease. TdT determination was negative in all 41 cases tested. Gene rearrangements were studied in 10 cases for IgH and TCR beta genes and in 5 cases for the TRG gene. No abnormal band beside the germ-line ones was detected in any of our cases, ruling out the presence of a minor neoplastic population. We can explain these results in at least three ways: first, the neoplastic population could represent less than 1% of the total, thus escaping detection by current techniques; second, the neoplastic population is not lymphoid in nature or is composed of mature cells that do not rearrange Ig and TCR genes and therefore belongs to a true non-B, non-T lineage; third, the pathogenesis of HD is completely different from that of non-Hodgkin's lymphomas (NHL) and does not involve the clonal expansion of a cell frozen at a particular maturative stage as is thought to happen in most NHL.

DNA Nucleotidylexotransferase↗
PubMedDate not supplied

[Acute cerebral multiple sclerosis: importance of a multiple diagnostic approach. Clinical case].

The Authors report a case of acute, apoplectiform, multiple sclerosis, with right hemiparesis and severe motor dysphasia. The way undertaken to arrive to the diagnosis of demyelinating disease is discussed, with special attention to the importance of a multiple diagnostic approach, analysing the sensitivity and the limits of the instrumental methods actually available.

Acute Disease↗
PubMedDate not supplied

Differential expression of c-jun, c-fos and hsp 70 mRNAs after folic acid and ischemia-reperfusion injury: effect of antioxidant treatment.

The regenerative repair response to folic acid and ischemia-reperfusion injury is characterized by different patterns of renal tubular cell proliferation. The purpose of this study was to examine the time course of the expression of two early growth response genes, c-jun and c-fos, and of the stress response gene hsp70 after such renal injuries and to determine the role played by reactive oxygen species generated during reperfusion, on gene induction. Ischemic injury caused an almost immediate increase of c-jun, c-fos and hsp70 mRNA expression, that reached a maximum at 1 h of reperfusion. Folic acid treatment increased c-fos and hsp70 mRNAs at 2 h, while c-jun accumulated at 1 h, although to a lesser extent. The intravenous administration of two antioxidant drugs, allopurinol or dimethyl sulfoxide (DMSO), 20 min before ischemia, to prevent the generation of oxygen free radicals during reperfusion, did not cause any change in gene expression. In contrast, the combined administration of allopurinol and DMSO reduced c-jun and c-fos mRNA expression as well as tubular cell damage at 1 h of reperfusion, although not at earlier times while hsp70 mRNA expression remained almost unchanged. Taken together, the results suggest that these scavengers, by reducing reactive oxygen species and renal damage during reperfusion, may affect the expression and/or persistence of transcripts involved in the control of epithelial cell proliferation.

Acute Kidney Injury↗