St. Cercet. Virusol. 36 (1) 2006

Contents

• 3 - Have the risk factors of HCV aquisition changed in Romania? - Camelia Sultana, Loredana Manolescu, Simona Ruţă [more...]

  Institute of Virology “Şt S Nicolau”, UMF “C Davila”, Bucharest, Romania

  Abstract. Hepatitis C Virus (HCV), a virus with parenteral route of acquisition and an extremely high chronicisation rate, infects in Romania between 500 000 and 1 000 000 people, and the number of new cases for one year is between 2800 and 5200. The serological screening of the blood for discovering the parenteral acquired infections had dramatically decreased the transmission of HCV post transfusion. The aim of the present study is to compare the risk factors and the behavior in two demographic similar groups of patients (infected and uninfected with HCV) and their implications in the transmition of the infection. Our results reveal the fact that the risk factors much implied in our country in transmiting HCV infection are: surgical interventions (82,14% vs 32,4%, p<0.001), blood transfusions before 1990 (35,7% vs 5,8%, p<0.001) and the use of improper tattoo techniques (3,57% vs 0,93%, p<0.001), while the dentistry and the injection interventions are equally distributed in both groups.

  Keywords: hepatitis C virus, risk factors, parenteral transmission, transfusions.

• 11 - Herpes virus infection from patients with lymphomas and patients with metastatic adenopathy - Coralia Bleotu¹, Carmen Cristina Diaconu¹, Camelia Grancea¹, Liliana Popescu², Simona-Maria Ruta¹, Mihaela Chivu¹, ConstanÅ£a Antipa¹, Luminita Welt², Ana Neagu1, Irina Alexiu1, Raluca DrăguÅŸin², Oana Ciocan2, Laura Dragomir¹, Mihaela CloÅŸcă2, C.R.Popescu2, Cristina Goia¹, Gabriela Anton¹ [more...]

  ¹â€žÅžtefan S. Nicolau” Institute of Virology, Bucharest, Romania
  ²ColÅ£ea Clinic Hospital, Bucharest, Romania
  Abstract. Considerable evidence has been accumulating in favor of a possible involvement of viral agents in pathogenesis of human cancers. The aim of this study was to determine the prevalence of EBV and CMV and to establish a correlation with viral reactivation in patients with laryngeal/pharyngeal cancer and patients with lymphomas with head and neck determination. Serum samples from 52 patients with laryngeal/pharyngeal cancer or lymphomas were evaluated in ELISA assay for presence of IgM VCA, IgG and IgM antibodies EBNA1, IgG and IgM antibodies CMV. The EBV DNA detection was done with specific primers by PCR. Tested serum presented high EBNA1 IgG reactivity in both groups. Detection of EBNA1 IgM antibodies, especially at patients with lymphomas, lead to the supposition that reactivation is frequent in patients with cancer. Despite the high seroprevalence of high avidity antibodies, usually associated with EBV reactivation DNA was scarcely found. Both groups were negative for anti-EBV-VCA IgM antibodies (< 20 IU/ml). CMV IgM antibodies were not detected, but only two probes were negative for IgG CMV antibodies. High IgG CMV titre (over 7 IU/ml), similar to pregnancy active infection (considered controls), was associated with reactivation. Our results suggest that virus reactivation may play an important role in cancers.

  Keywords: EBV, CMV, virus reactivation.

• 23 - Effects of nonenzynatic glucosylation on the cytophilic property of human IgG of diabetic patients - Mirela Hirt¹, Mioara Manciulea¹, D. CheÅ£a², Iulia Popescu³, Lorelei Irina BraÅŸoveanu¹ [more...]

  ¹Center of Immunology - „Ştefan S. Nicolau” Virology Institute, Bucharest, Romania
  ²â€žN. Paulescu” Institute of nutrition and metabolism, Bucharest, Romania
  ³ University of Pittsburgh, Pittsburgh PA, SUA
  ABSTRACT. Human NK cells interact in vitro via FcγRIIIA with monomeric IgG (mIgG). This binding induceds a dose-dependent down-regulation of NK cell activity. On the other hand we have also noted remarkable quantitative and qualitative changes of serum IgG in diabetics. To extend these observations, in the present study we evaluated the modulatory effects of mIgG isolated from a group of 50 diabetic patients on the cytolytic function of human NK cells isolated from normal, healthy donors. In comparison with the percentage of inhibition induced by normal mIgG (66.8%) we have demonstrated qualitative modifications of the cytophilic property of mIgG molecules induced by nonenzymatic glycosilation of diabetic patients.

  Keywords: immunoglobulins (Ig); Fc receptors (FcR); diabetus; nonenzymatic glycosilation.

• 29 - The prevalence of chlamydia trachomatic’s LPS antigen in men with urethritis - Viviana Dragodan, ConstanÅ£a Antipa, M. Stoian [more...]

  „Ştefan S. Nicolau” Institute of Virology, Bucharest, Romania
  Abstract. We evaluated during January-December 2005 in the Institute of Virology – 170 male subjects aged 17-57, with different professions, having all in common the clinical diagnose that was urethritis. From the total studied urethritis 42.3% were acute forms (primo infections), and 57% were recurrences. The infectious etiology was established by Chlamydia LPS antigen detection in 41.1% of cases, (46.5% were primo infections, 37.1% were recurrences). Anti Chlamydia Trachomatis IgG antibodies were detected in 13.5% of cases, (9.5% primo infections, 16.4% recurrences). 20 % of the patients were at the same time seropositive and had LPS antigen.

  Keywords: Chlamydia trachomatis, urethritis, antigen LPS.

• 35 - Study using the combination of methotrexate and leflunomide in the treatment of rheumatoid arthritis - Marinela Bostan¹, Stefania Marineata², Mirela Hirt¹, Lorelei Irina Brasoveanu¹ [more...]

  ¹Center of Immunology - “Stefan S. Nicolau” Institute of Virology, Bucharest, Romania
  ²Medical Center Vademecum, Bucharest, Romania
  Abstract. Since the therapy with methotrexate is not remission-inducing in rheumatoid arthritis, many protocol therapies try to combine it with other drugs in order to achieve a better therapeutic response. The aim of the present study is to analyse the efficacy of combinated therapy – leflunomide (LFN) - methotrexate (MTX) in a group of patients in which monotherapy with MTX was not efficient. Therefore, in order to analyse the effect of combination therapy – LFN+MTX on the expression of several immunological markers and the cellular functions developed by cells involved in the pathogeny of RA we used direct immunofluorescence method, chemotaxis test and lucigenin amplified chemiluminescence method. Our results show the association of two antimetabolic agents, leflunomide and methotrexate, could be effective and safe, with careful liver enzyme and hematologic monitoring. In addition, the combined leflunomid and methotrexate therapy induced a significant decrease of chemotactic and oxidative functions developed by polymorphonuclear cells (PMNs) in RA. The results obtained by present study might offer a novel therapeutical approach in controlling the inflammatory and destructive processes in rheumatoid arthritis.

  Keywords: rheumatoid arthritis, methotrexate, leflunomide, cytometry, chemiluminescence.

• 45 - Molecular docking computation on the biological active compounds from hypericum perforatum - C.N. Zaharia¹ and D. Popescu² [more...]

  
  ¹â€žÅžtefan S. Nicolau” Institute of Virology, Bucharest, Romania
  ² University of Bucharest, Faculty of Biology, Bucharest, Romania
  Abstract. Molecular docking computational are frequently used to studying protein–ligand interactions (P-L). In this paper the searching and scoring method has analysed in detail. The affinity grids  are used for the macromolecular structure and are calculated on the basis of force field potentials for van der Waals and electrostatic interactions. Using the molecular simulation programs, CHARMM and AUTODOCK, the 3D structure of the serotonine transporter (SERT) have established. The activity of hypericin (HY) and hipeforin (HP), two active antidepressant compounds, on the 5-HT transporters have studied.   The docking energy for both complexes SERT – HY and SERT – HP were calculated. An interesting result was obtained regarding the rolle of the aspartic acid 98, izoleucine 102, fenilalanine 117, tyrozine 121, methionine 124, leucine 547 and isoleucine 552 from SERT structure, on the binding of HY and HP on the active site.

  Keywords: Hypericin, hyperforin, serotonine transporter, depression, molecular docking.

• 53 - The study of the human genome instability induced by the ageing process - Natalia Cucu¹, Liliana Burlibasa¹, Mioara Matei³, Anca Botezatu² [more...]

  ¹ University of Bucharest, Biology Faculty, Genetic Department
  ² „Stefan S. Nicolau” Institute of Virology, Bucharest, Romania
  ³ General Hospital CF2, Bucharest, Genetic Department
  Abstract. The ageing process involves a slowly decline of the physiological status of the organism and an increase of the susceptibility related to diseases: atherosclerosis, stroke, myocardial infarct, Alzheimer, cancer, cataract, etc. Ageing is characterized by an alteration of the DNA methylation process, and that is demonstrating the relation between the epigenetic modification of the genome and the certain period of organism development. During ontogeny of the pluricellular organisms are established some DNA methylation patterns, specific for each tissue, vital for normal development. A general correlation between the alteration of the DNA methylation pattern and ageing, suggest a global DNA hypomethylation and genomic instability, with some sites hypermethylated. The genes involved in this process are equal exposed to an aberrant activity or repression, with important repercussions for development and for survival of a person at this age.

  Keywords: DNA methylation, genomic instability, angiotensin-converting enzyme (ACE), methyl-tetrahydro folate reductase (MTHFR), homocysteinemia.

• 63 - Fractal methods used to characterize subcellular structures - Loretta Ichim [more...]

  „Ştefan S. Nicolau” Institute of Virology, Bucharest, Romania
  Abstract.In this current study I focused on the use of to fractal methods at the subcellular structures. I determined the changing in size distribution of the cell nuclei by fitting measured light scattering spectra to the predictions of the Mie theory. My results indicated that the fractal analysis might be a reliable tool for accurately determination between viruses’ infected biological samples and non-infected ones.

  Keywords: fractal dimension, Mie scattering, spectra, signal analysis.