PubMed Health⌕ Search

Biomedical subjects

R Marasca

Publications and source records attributed to R Marasca.

At least 55 records · Page 3Linked to original sources
PubMed1995

Detection of PML-RAR alpha fusion transcript in Ph positive leukemia with acute promyelocytic phenotype lacking the t(15;17) cytogenetic abnormality.

A 39-year-old woman was diagnosed with acute promyelocytic leukemia (APL) with disseminated intravascular coagulation syndrome. The hematologic examination showed a morphologic, cytochemical, and immunophenotypic picture typical of an APL, with a marked leukocytosis and a mixed population of hypergranular and microgranular promyelocytes. The cytogenetic analysis showed a 46,XX,t(9;22) karyotype, without any alterations of chromosomes 15 and 17. The t(15;17) translocation was not evident in FISH experiments, while a molecular analysis revealed the presence of a PML-RAR alpha chimera.

Adult↗
PubMed1994

Double P53 point mutation in extramedullary blast crisis of chronic myelogenous leukemia.

A patient with Philadelphia-positive chronic myelogenous leukemia (CML) evolved in extramedullary blast crisis, was studied for the presence of alterations of the P53 tumor suppressor gene in the different stages of disease progression. No P53 gene aberrations were detected during the chronic and accelerated phases. Two identical missense point mutations, involving codons 249 and 281 and leading to the amino acid substitutions Arg-Ser and Thy-Asp, were identified in cells of an extramedullary mass and then in peripheral blood blast crisis cells. The data indicate that the medullary and extramedullary blast cells belong to the same cellular clone. They also strongly suggest that in this case, the alteration of P53 gene is strictly related to the progression of the disease, although this mechanism is certainly neither the only nor the most frequent molecular event leading to the acute phase.

Adult↗
PubMed1993

Three cases of human herpesvirus-6 latent infection: integration of viral genome in peripheral blood mononuclear cell DNA.

Saliva and peripheral blood mononuclear cells from three patients, two with lymphoproliferative disorders and one suffering from multiple sclerosis, were examined for the presence of human herpesvirus-6 (HHV-6) genome by using the polymerase chain reaction and Southern blot analysis. The search for anti-HHV-6 antibodies, carried out in the sera of the same cases by an immunofluorescence assay, was negative in two cases at the lowest dilution used (1:40). These three patients had a high number of HHV-6 specific sequences in uncultured peripheral blood mononuclear cells, which are thought to be a normal site of viral latency although, in healthy individuals, the infected cells are extremely rare. In order to gain some insight into the state of the viral genome in this latent HHV-6 infection, we used pulsed field gel electrophoresis to separate HHV-6 DNA directly from HHV-6 (strain GS) infected HSB-2 cells and from the peripheral blood mononuclear cells of these three patients. Our study showed the presence of intact viral genome, of the expected length of 170 kb, persisting as free extrachromosomal element in the HSB-2 cells but not in patients' peripheral blood mononuclear cells. On the other hand, in strong contrast with the results obtained in infected HSB-2 DNA, the restriction analysis of the three patients' peripheral blood mononuclear cell DNA showed fragments of molecular weight constantly higher than the 170 kb segment, indicating that the viral sequences are linked to high molecular weight cellular DNA.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

Frequent detection of human herpesvirus-6 sequences by polymerase chain reaction in paraffin-embedded lymph nodes from patients with angioimmunoblastic lymphadenopathy and angioimmunoblastic lymphadenopathy-like lymphoma.

In search of a possible involvement of viral agents in angioimmunoblastic lymphadenopathy with dysproteinaemia (AILD) and AILD-like lymphoma (AILD-L), we studied the presence of human herpesvirus-6 (HHV-6) in the lymph node biopsies of 12 cases by polymerase chain reaction (PCR). Given the rarity of this lymphoproliferative disorder, we investigated archival specimens, consisting of formalin-fixed and paraffin-embedded tissues, obtained from patients with a clinical and histologic diagnosis of AILD and AILD-L. HHV-6 sequences were detected in the lymph node biopsies of 7 out of the 12 AILD and AILD-L cases examined. HHV-6 sequences were identified also in the involved liver and spleen tissues of one patient and in the PBMCs of two patients, all carrying viral sequences in the affected lymph nodes. We also used PCR to characterize the HHV-6 genomes, showing that two different viral strains are represented in the pathologic tissues. This study provides evidence of the presence of HHV-6 specific sequences in an unexpectedly high proportion of our series of AILD and AILD-L cases, suggesting a possible involvement of this lymphotropic virus in the pathogenesis of at least some cases of the disease.

Base Sequence↗
PubMed1993

Human herpesvirus 6 and multiple sclerosis: survey of anti-HHV-6 antibodies by immunofluorescence analysis and of viral sequences by polymerase chain reaction.

A possible involvement of human herpesvirus 6 (HHV-6) infection in the pathogenesis of multiple sclerosis (MS) was investigated. The immunofluorescence analysis of sera from 126 MS patients showed significantly higher anti-HHV-6 antibody titres in MS sera than in 500 normal controls. A polymerase chain reaction (PCR) assay of the peripheral blood mononuclear cell (PBMC) DNAs of 31 MS patients and 24 normal subjects was positive in one normal control and in one MS patient. The Southern blot analysis indicated an unexpectedly high level of viral sequences in the MS patient, but not in the control. Since viral sequences are rarely present in MS subjects, the high anti-HHV-6 antibody titres found in MS are likely to be related to immune impairment rather than reactivation of a latent infection.

Adolescent↗
PubMed1993

Failure to detect genomic material of HTLV-I or HTLV-II in mononuclear cells of Italian patients with multiple sclerosis and chronic progressive myelopathy.

To contribute to the undecided question if a retrovirus of the human T-cell lymphotropic virus (HTLV) family may be involved in the development of multiple sclerosis (MS), we investigated by the polymerase chain reaction (PCR) the presence of HTLV-I and HTLV-II sequences in the peripheral blood mononuclear cell DNAs from 30 patients affected by MS and 15 by chronic progressive myelopathy. Moreover a control group of 14 blood donors was examined. All these patients were devoid of anti-HTLV-I antibody in the serum and cerebrospinal fluid at ELISA. For the PCR, primers and probes specific for the tax region common to HTLV-I and HTLV-II, for the pol region of HTLV-I, and for the pol region of HTLV-II were used. In spite of the high sensitivity of the technique used, the three groups of subjects were negative for HTLV-I and HTLV-II genomic sequences.

Adult↗
PubMed1991

Human herpesvirus-6 in human lymphomas: identification of specific sequences in Hodgkin's lymphomas by polymerase chain reaction.

In search of a possible involvement of the human herpesvirus type 6 (HHV-6) in human Hodgkin's and non-Hodgkin's lymphomas, we studied the levels of anti-HHV-6 antibodies in the sera of 94 cases by an immunofluorescence assay, as well as the presence of HHV-6 sequences in the affected tissues of 66 cases by polymerase chain reaction, using one set of primer oligonucleotides. Our results showed higher anti-HHV-6 antibody titers in human lymphomas than in normal blood donors, but the difference is statistically significant only when normal donors are compared with Hodgkin's lymphoma cases. HHV-6 sequences were detected in 3 of 25 Hodgkin's lymphomas and 0 of the 41 cases of non-Hodgkin's lymphomas studied. The three cases positive for HHV-6 sequences belong to the nodular sclerosis-lymphocyte depletion histologic subtype and share remarkable similarities in their clinical features. Furthermore, Southern blot analysis of total genomic DNA obtained from the neoplastic tissues of two of the three patients showed the same restriction fragment length polymorphism. Our results suggest that: (1) the high level of anti-HHV-6 antibodies in Hodgkin's disease is due to an activation of the immune system not related to the presence of HHV-6 sequences in affected lymph nodes; (2) the presence of HHV-6 sequences in human lymphoid tissues is not a frequent event, rather it is in fact a very rare event in non-Hodgkin's lymphomas, while in Hodgkin's cases it is more frequent than previously reported on the basis of Southern blot analysis; and (3) the presence of HHV-6 sequences in Hodgkin's lymphomas may have a relation with the clinical presentation of the disease.

Adult↗
PubMed1991

[Malignant tumors of the palate. Histology, diagnosis and therapy].

The Authors describe the most important malignant tumors of the palate, considering the histological, clinical and Rx aspects. The exact and early evaluation of these tumors allows a right therapeutic procedure with the possibility of avoiding surgical complete demolition of the upper jaw. On this purpose the Authors underline the importance of the early diagnosis. A follow-up study of forty-five cases is described. All the patients had a resection of the upper jaw. In this study it's evident that a diagnostic inadmissible delay is the cause of a high number of cases at an advanced stage, all that to the prejudice of the quality and prospect of life.

Adult↗
PubMedDate not supplied

Cellular localization of human herpesvirus 8 in nonneoplastic lymphadenopathies and chronic interstitial pneumonitis by in situ polymerase chain reaction studies.

OBJECTIVES: To study the cellular localization of human herpesvirus 8 (HHV-8) in rare cases of HHV-8 infection from Italy that are associated neither with human immunodeficiency virus (HIV) infection nor Kaposi's sarcoma (KS). METHODS: The presence and distribution of HHV-8-infected cells was investigated by direct in situ polymerase chain reaction (PCR) in the lymph node tissues from 2 patients with reactive lymphadenopathies with florid follicular hyperplasia and increased vascularity and in the lung tissue from 1 patient with chronic interstitial pneumonitis. RESULTS: HHV-8 was localized in lymphoid and monocyte-macrophage cells scattered in the interfollicular regions of both lymph nodes but not in endothelial cells. In the lung tissue, HHV-8 was found in the inflammatory cells infiltrating the interalveolar interstitium, in endothelial cells of the pulmonary vasculature, and in rare pneumocytes. CONCLUSIONS: HHV-8 can infect nonneoplastic lymph nodes of immunocompetent subjects, and the distribution of infected cells outside of the germinal centers resembles that of Epstein-Barr virus (EBV)-infected cells in the lymph nodes in the course of infectious mononucleosis. Endothelial cells and pneumocytes may be a target of HHV-8 infection out of the KS setting, at least in the presence of a chronic inflammatory process.

Herpesviridae Infections↗
PubMedDate not supplied

[Identification of human herpesvirus HHV-6 sequence in a case of Hodgkin's disease by polymerase chain reaction].

In the last decades new approaches to the diagnosis and treatment of Hodgkin's Disease (HD) have contributed to improved rates of survival and cure but the pathogenesis of the disease still remains unknown. Data have been collected suggesting a relationship between viral infections and HD. HD patients with evidence of Epstein-Barr virus genomes in their affected tissues have been recently reported. Human Herpes Virus six (HHV-6) is a newly isolated virus, derived from patients with lymphoproliferative disorders. In order to investigate the possible role of this virus in the pathogenesis of HD we looked for a specific segment of HHV-6 genome by means of the polymerase chain reaction (PCR) in tissue samples obtained from peripheral blood and lymphnodes in HD patients: one clearly positive case has been identified. This result is the first indication of HHV-6 sequences associated with a case of HD and raises the possibility that this virus might be involved in the pathogenesis of this lymphoproliferative disorder. The relationship between HHV-6 and HD therefore warrants further investigation.

DNA, Viral↗