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Biomedical subjects

A Pugliese

Publications and source records attributed to A Pugliese.

At least 37 records · Page 2Linked to original sources
PubMed2001

Sexually transmitted infections and cervicovaginal dysplasia in a cohort of human immunodeficiency virus-positive women in Turin.

The correlation between sexually transmitted infections and cervicovaginal dysplasia has been evaluated in a cohort of 135 women who tested positive for human immunodeficiency virus type I (HIV-1) and were admitted to Amedeo di Savoia Hospital of Turin during the years 1997 and 1998 (stages B2 and B3 or C2 and C3). Of these women. 31 presented with sexually transmitted diseases (STDs; mean age, 33.5 +/- 5.9 years). Among them, 14 were affected by cervicovaginal dysplasia of differing severity; human papillomavirus (HPV) infection was found in 13 subjects (10 with cervicovaginal dysplasia). Herpes simplex virus type 2 (HSV-2) infection was detected in six women. Finally, Trichomonas vaginalis and Candida albicans were found in 10 and in 6 patients, respectively. Immunologic and hematologic evaluations were performed in the patients affected by STDs; in 28 patients of our case report unaffected by STDs but of similar ages (34.1 +/- 5.6 years) and stage of infection; and in 20 HIV-negative women unaffected by STDs. A significant reduction among the patients affected by STDs, as compared to those unaffected, was found in the case of white cells, CD4+ T cells, and ratio values (CD4 +/ and CD8 + T cells). Moreover, red cell count and hemoglobin concentration were lower in those women in the STD group. A lack of correlation was found between HIV RNA loads and CD4 + T cell counts and between HIV RNA and hemoglobin concentration in the patients with cervicovaginal dysplasia and in those affected by HSV-2 infection, which differed from the findings in subjects affected only by trichomoniasis or candidiasis. This suggests that the two former pathologic conditions (cervico-vaginal dysplasia and HSV-2 infection), other than HIV- I infection, may contribute to the impairment of these values. Moreover in our case report, T vaginalis and HSV-2 infections, which are suspected to have an oncogenic potential, do not seem to be relevant in the induction or facilitation of genital neoplastic diseases. Noteworthy is that the patients affected by HSV-2 infection, such as those affected by genital neoplastic diseases, showed the most compromised values of total white cells, CD4+ T cells, ratio index, red cells, and hemoglobin concentration.

Adult↗
PubMed2001

Human infections tick-transmitted.

In this monograph are analysed the principal infections transmitted by ticks and particularly those interesting Europe and North America. Besides the main species of these arthropods are described in consideration of their characteristics and geographic diffusion. In particular the infections caused by Borrelia genus and tick born encephalitis virus are treated more exhaustively in consideration of their potential severity and because the diagnosis of these infections is sometimes difficult. However also the main rickettsial infections transmitted by ticks are reported together the hemorragic fevers transmitted by such arthropods. In particular it is exhaustively analysed the Mediterranean tick fever in consideration of its presence in some regions of Italy and of the wrong opinion of considering this pathology not very severe. Lastly has been included a treatment about some emergent infections transmitted by ticks, like as the ehrlichiosis and babesiasis, but also the mention of tularaemia that can be considered a re-emergent infection, also in consideration of the epidemic focus now present in Kossovo. The above-mentioned pathologies are analysed also as regards the laboratory diagnosis (direct and serologic methods), the therapeutic treatment and the prophilaxis, both directed against the arthropods vectors and that of individual type, employing also some vaccines, when disposable.

Animals↗
PubMed2000

Inhibition of Fas-mediated apoptosis in mouse insulinoma betaTC-3 cells via an anti-Fas ribozyme.

In this study we have designed and constructed an anti-Fas ribozyme and show that it can specifically cleave the Fas mRNA in vitro. Moreover, to test its efficacy ex vivo, we transfected the anti-Fas ribozyme into betaTC-3 insulinoma cells, using a RNA polymerase III promoter to drive its expression. Like pancreatic beta cells, betaTC-3 cells do not constitutively express Fas, but Fas expression can be induced with IL-1 and IFN-gamma. Transfected cells expressed an average of 5000 copies of anti-Fas ribozyme transcript per cell as assessed by reverse transcriptase-real-time PCR. After IL-1/IFN-gamma treatment, betaTC-3 cells transfected with the anti-Fas ribozyme expressed 80% less Fas compared with mock-transfected cells. In addition, the anti-Fas ribozyme also inhibited Fas expression in NIT-1 insulinoma cells and in primary cultures of dispersed pancreatic islet cells. Inhibition of de novo Fas expression in betaTC-3 cells expressing the anti-Fas ribozyme correlated with resistance to Fas-mediated apoptosis as determined by the number of cells exhibiting caspase 3 proteolytic activity. Hence, we have engineered a ribozyme capable of preventing Fas expression in the betaTC-3 pancreatic insulinoma cell line and conferring resistance to Fas-mediated apoptosis. We suggest that ribozymes may be potentially useful to engineer resistance to apoptosis in transplantable beta cells, a feature that may significantly improve the survival of islet cell grafts.

Animals↗
PubMed2000

Candida albicans and HIV-1 Infection.

Candida albicans virulence is in part mediated by fibronectin (FN) interaction. We compared the adherence level to FN (using Becton Dickinson FN-coated plates) of several strains of yeast isolated from HIV-1 infected or uninfected subjects affected by candidiasis (30 strains from HIV+ subjects and 18 from HIV- subjects). More adhesive strains were found in HIV+ patients than in HIV- subjects. In particular a mean increase of 120 per cent as regards the total number of adhesive cells and 230 per cent as regards the adhesive cells producing germ tubes was detected in the former group of strains as compared to the latter ( p < 0.001 in both cases). The enhancement of FN expression induced by HIV-1 infection, as we have previously demonstrated, can increase interest in the adherence to FN of C. albicans strains isolated from AIDS-affected patients. Moreover, we also underline the important role played by HIV Nef protein in increasing the C. albicans aggressiveness. In fact a significant inhibitory effect of Nef on the phagocytosis of this yeast by macrophages has been demonstrated and the oxidative processes of these cells seem to be down-regulated by this protein.

Candida albicans↗
PubMed2000

Coexistence of macroparasites without direct interactions.

Coexistence of macroparasites is studied by extending the infinite-dimensional model considered by Anderson and May (1978, J. Anim. Ecol. 47, 219-247, 249-267) to several species of parasites that are assumed to interact only by causing the death of a common host. An exact invadability condition is found for this model. By studying when mutual invasibility is possible, the region where two parasite species can coexist is found. The result is that, if there is a trade-off between virulence and transmissibility, then coexistence of two species of parasites is possible, but only when the parameters of the model fall into a very narrow parameter region. If, on the other hand, one parasite is more virulent and less transmissible, then it will be competitively excluded. This latter result, though expected in terms of competition theory, is in contrast with what found in the approximate models so far used for studying interacting macroparasites. The effect of parasite aggregation on coexistence is studied by considering two modifications of the basic model (clumped infections and host population heterogeneity in predisposition to infections) that allow for higher aggregation. It appears that the width of the coexistence region is insensitive to these modifications.

Host-Parasite Interactions↗
PubMed2000

Substrate specificity of the brush border K+-leucine symport of Bombyx mori larval midgut.

L-leucine uptake into membrane vesicles from Bombyx mori larval midgut was tested for inhibition by 55 compounds, which included sugars, N-methylated, alpha-, beta-, gamma-, delta-, epsilon-amino acids, primary amines, alpha-amino alcohols, monocarboxylic organic acids and alpha-ketoacids. Based on cis-inhibition experiments performed at the high pH (10.8) characteristic of the midgut luminal content in vivo, we find that the carrier binding site interacts with molecules which possess a well-defined set of structural features. Amino acids are preferentially accepted as anions and the ideal inhibitor must have an hydrophobic region and a polar head constituted by a chiral carbon atom bearing two hydrophilic groups, a deprotonated amino-group and a dissociated carboxylic group. Binding is reduced if one of the two hydrophilic groups is removed. Lowering the pH to less alkaline value (8.8) only affects the affinity of delta- and epsilon-amino acids, which are excluded from binding because of their positively charged side-chain. Modifications of the potassium electrochemical gradient increased the affinity constant values of the molecules, but have little effect on the rank of specificity. Physiological implications of the data reported are discussed.

Amino Acid Transport Systems↗
PubMed2000

Levels of the bcl-2 protein, fibronectin and alpha(5)beta(1) fibronectin receptor in HIV-1-infected patients with Kaposi's sarcoma.

Kaposi's sarcoma (KS) is an angioproliferative disease characterized by proliferation of neoplastic cells (spindle cells) mixed with endothelial and inflammatory cells. In this study we evaluated the role of the adhesive glycoprotein, fibronectin (FN) and its receptor alpha(5)beta(1) (FNR), and the proto-oncogene bcl-2, an anti-apoptotic protein. Significantly decreased serum levels of FN were noted in HIV-1-infected patients with KS, whereas serum levels of FNR were significantly increased in the same patients. Furthermore, increased FNR expression was observed on CD4 cells from KS patients. Serum levels of bcl-2 protein were significantly decreased in asymptomatic seropositive patients, whereas HIV-1-infected patients with KS showed increased serum levels of bcl-2. These results provide further information about interaction between integrins and the extracellular matrix and bcl-2 protein that can support cell survival either of neoplastic cells or endothelial and inflammatory cells.

AIDS-Related Opportunistic Infections↗
PubMed2000

Impact of highly active antiretroviral therapy in HIV-positive patients with cardiac involvement.

OBJECTIVES: Cardiac involvement is frequently observed in HIV-infected patients, especially in those in the late stage of the disease. This study was designed to evaluate the impact of highly active antiretroviral therapy (HAART) in patients with cardiac involvement. METHODS: A retrospective study of 1042 patients admitted to a Division of Infectious Diseases between 1989 and 1998. During the period 1989-1995, 544 patients were treated with nucleoside reverse transcriptase inhibitors (NRTI), whereas 498 patients were treated with HAART during the period 1996-1998. RESULTS: Cardiac involvement, including arrhythmias, pericarditis, ischaemia, dilated cardiomyopathy, endocarditis, pulmonary hypertension, and myocarditis were observed in 282 of 544 (51.8%) patients treated with NRTI, compared with 93 of 498 (18.6%) patients with HAART (P < 0.0001). CONCLUSIONS: HAART has significantly decreased the incidence of cardiac involvement, especially pericarditis, arrhythmias, and dilated cardiomyopathy.

Adult↗
PubMed2000

Anti-inflammatory response of IL-4, IL-10 and TGF-beta in patients with systemic inflammatory response syndrome.

The systemic inflammatory response syndrome (SIRS) is an inflammatory process seen in association with a large number of clinical infective and non-infective conditions. The aim of this study was to investigate the role of anti-inflammatory cytokines such as interleukin-4 (IL-4), interleukin-10 (IL-10), and transforming growth factor-beta (TGF-beta). Serum levels of IL-4, IL-10 and TGF-beta were determined in 45 patients with SIRS: 38 patients had SIRS of infectious origin, whereas seven patients had non-infectious SIRS. Twenty healthy subjects were used as controls. Serum levels of IL-4, IL-10 and TGF-beta were determined by an immunoenzyme assay. A significant increase of IL-4 was observed in these patients at the time of diagnosis and 5 days later. In contrast, serum levels of IL-10 were not increased at the time of diagnosis, but a slight decrease was noted after 5 days. Serum levels of TGF-beta were not increased at time of diagnosis, and a slight increase was observed after 5 days. Serum levels of IL-4 were significantly higher in patients with infectious SIRS at the time of diagnosis, whereas no significant difference between infectious and non-infectious SIRS was noted for serum levels of IL-10 and TGF-beta at the time of diagnosis and 5 days later. During SIRS, serum levels of IL-4 were significantly increased with a significant correlation between IL-4 and mortality, and only levels of IL-4 were significantly increased in the SIRS caused by infectious stimuli.

Adult↗
PubMed2000

Multifunctional activity of recombinant p14 on lymphoid cell cultures.

Some effects of recombinant p14, a protein encoded by the tat gene of immunodeficiency virus type 1 (HIV-1), were investigated on T lymphocytic cell cultures. In particular, we detected p14 adsorption to cells, the rate of cell replication, the expression of fibronectin (FN) and its receptor (FNR) and of cell surface CD4 antigen in HIV-1-infected or uninfected MT-4 and H9 cells, treated with p14. Moreover, we evaluated the proportion of apoptotic cells in uninfected and chronically infected H9 cells in the presence of p14 and the modulation of interferon (IFN) production induced by p14 in PBMC of healthy subjects. The results obtained demonstrate that p14 exerts multifunctional activities on HIV-1 infected and uninfected cells. In particular, this protein interacts in a specific manner with cell surface, especially with that of infected cells, and enhances the expression of FN and FNR but not that of the CD4 lymphocyte antigen. Moreover, p14 increases cell replication, IFN production and can exert a slight modulation of apoptosis. We also propose a model to explain a possible role in HIV-1 infection of the effects of exogenous p14.

Adsorption↗
PubMed2000

Human herpesvirus 8 and associated diseases in a group of 67 human immunodeficiency virus-seropositive individuals.

Human herpesvirus 8 (HHV-8) is involved in the pathogenesis of Kaposi's sarcoma, of B-cells lymphomas, and of Castelman's disease. However, the role of this virus is not yet well known. To investigate the relationship between HHV-8 infection and diseases correlated with human immunodeficiency virus (HIV), we studied a cohort of 67 HIV-seropositive subjects, some of them coinfected with HHV-8. An indirect immunofluorescence test was employed to detect the antibodies against this virus. Positive cases were 31 (46.3%); among the 67 patients, 14 were weakly positive, or + (20.9%); 11 were significantly positive, or ++ (16.4%); and 6 were strongly positive, or (8.9%). These last six patients were the most affected by opportunistic infections, and all were affected by neoplastic pathologies. Moreover, the HHV-8 positive subjects showed hematologic and martial alterations more severe than those in the negative subjects. HHV-8 seroprevalence in HIV-seropositive patients of our cohort was higher (46.3%) than in normal population (0-10%). The presence of disseminated Kaposi's sarcoma and other neoplasms associated with high HIV-RNA levels in HHV-8-positive patients, and particularly in those with strong positivity, corroborates the hypothesis that the virus is correlated with the progression of HIV infection and with its related diseases, especially those that are neoplastic. Last, the severe alterations of iron metabolism found in the patients coinfected with HHV-8 and the negative effect of this virus on the lymphocytic populations can contribute to the unfavorable evolution of HIV infection and also might facilitate tumor development.

Adult↗
PubMed1999

Effect of Aspergillus terreus mycotoxins on nitric oxide synthase activity in human erythroid K-562 cells.

Because several stimuli of microbial origin enhance the activity of nitric oxide synthase (NOS) in human cells of the myeloid lineage, we decided to investigate whether cellular damage induced by Aspergillus terreus mycotoxins could be associated with an increase in NOS activity. A pool of mycotoxins rather than individual toxins was tested so that the natural conditions could be mimicked. In the present study, we report that a crude extract of A. terreus induces cellular damage and increases NOS activity in K-562 cells, an erythroleukaemic cell line in which NOS is particularly active. The specificity of this association was further investigated by using NOS inhibitors and by comparing, in the same cellular model, the effects of the extract with the activity of other microbial toxins of a defined mechanism of action. Canavanine, an inhibitor of NOS, significantly reduced cell death in the presence of the extract, suggesting that cellular damage, induced by the mycotoxins of A. terreus is at least in part mediated by NOS activity. Moreover, Escherichia coli lipopolysaccharide (LPS), known to be a potent NOS inducer, increased NOS activity in our experimental model as well. In contrast, Bordetella pertussis toxin did not show any effect on NOS activity. The results of this study suggest that NOS may be involved in mycotoxicoses.

Aspergillosis↗
PubMed1999

Modulation of surface transferrin receptors in lymphoid cells de novo infected with human immunodeficiency virus type-1.

To investigate whether transferrin receptor (CD71) expression is affected by acute HIV-1 infection, three different lymphoid cell lines (MT-4, SUPT-1, H9) were infected with HIV-1 and tested for surface CD71 expression after different incubation periods depending on cell survival after infection. We found that expression of surface CD71 was lower in cells infected with HIV-1 than in uninfected controls: the timing and extent of this down-modulation depended apparently on the different susceptibility of the cell lines to HIV-1 infection and cytopathogenicity. Citrate, a molecule capable of chelating iron, dose-dependently prevented down-modulation of surface CD71 in HIV-1 infected cells as well as viral cytopathic effects. We conclude that (i) expression of surface transferrin receptors is down-modulated by acute HIV-1 infection in T lymphoid cells, that (ii) this cell phenotypic modulation is associated with the cytopathic effects of the virus, and that (iii) these phenomena are modulated by iron chelation. These results support the view that iron metabolism may be an important area for interaction between HIV-1 and human cells.

ADP-ribosyl Cyclase↗
PubMed1999

Effects of the exogenous Nef protein on HIV-1 target cells.

Nef is a multifunctional gene of HIV which can increase virus replication either directly or by modulating the target cell's metabolism. Nevertheless the role of the exogenous Nef protein is not yet well understood. To investigate it, we studied the effects of the recombinant Nef protein on the expression of some antigens of lymphoid T-cells permissive to HIV-1 replication, and on their proliferation and on apoptosis induction. For this purpose, we utilised MT-4 and H9 T-cell lines. We evaluated FN (fibronectin), CD4 and CD71 expression in uninfected and acutely or chronically infected cells, both untreated and treated with Nef. Our studies showed a significant up-regulation of FN especially in uninfected cells, with a dose of 2.5 microg ml(-1); in contrast, a significant down-modulation of CD4 and CD71 both in uninfected and in acutely or chronically infected cells, was detected. The proliferation of H9 uninfected cells was significantly reduced 24 h after treatment with Nef protein in a dose-dependent manner (ranging from 0.02 to 2.5 microg ml(-1)); likewise a significant inhibition of proliferation of acutely and chronically infected cells was evident with 2.5 microg ml(-1). Moreover, we demonstrated a dose-dependent activity of Nef on inducing apoptosis in H9 uninfected cells and no effects of this protein on modulation of INF alpha and gamma production in peripheral blood mononucleated cells of health donors. Nef appeared to be able to increase the effect of apoptotic stimuli. In conclusion, our data suggest that in our experimental system, the exogenous Nef protein can inhibit cellular synthesis facilitating the metabolic pathway involved in virus replication. In addition it modulates the susceptibility to the HIV-1 infection and finally, that apoptosis induction or enhancement can facilitate the release of neoformed virions.

Antigens, CD↗
PubMed1999

Periodic solutions: a robust numerical method for an S-I-R model of epidemics.

We describe and analyze a numerical method for an S-I-R type epidemic model. We prove that it is unconditionally convergent and that solutions it produces share many qualitative and quantitative properties of the solution of the differential problem being approximated. Finally, we establish explicit sufficient conditions for the unique endemic steady state of the system to be unstable and we use our numerical algorithm to approximate the solution in such cases and discover that it can be periodic, just as suggested by the instability of the endemic steady state.

Acquired Immunodeficiency Syndrome↗
PubMed1999

Modulation of in vitro chemosensitivity in acute myelogenous leukemia cell line by GM-CSF: opposing effects observed with different cytotoxic drugs and time exposure.

In some studies the GM-CSF (granulocyte-macrophage colony-stimulating factor) increased the in vitro sensitivity of acute myeloid leukemia (AML) cells to cytosine arabinoside (Ara-C), however, in clinical trials no favorable effects were shown. We used a GM-CSF responsive AML cell line (AML 193) to test the effects of growth stimulation on in vitro efficacy of Ara-C and methotrexate (MTX). In 6 days continuous exposure, dose dependent Ara-C cytotoxicity was counteracted by GM-CSF. Conversely, MTX cytotoxicity was increased significantly. However, in a short term treatment (24 h, high doses) the GM-CSF increased both MTX and Ara-C cytotoxicity. These effects might depend on different drug regimens and cell features.

Antimetabolites, Antineoplastic↗
PubMed1999

Regulation of inflammatory responses to Bordetella pertussis by N(G)-monomethyl-L-arginine in mice intranasally infected.

To investigate effect of MMLA, an inhibitor of nitric oxide (NO) production, on regulation of inflammatory responses to Bordetella pertussis infection, mice were infected intranasally, and treated with various concentrations of MMLA. Ten days after infection, mice treated with MMLA at dosage of 100 mg/kg, given intraperitoneally in a single dose or for 5 consecutive days, showed at histopathologic examination, a significant decrease of intensity of inflammation (scores, 0.6 +/- 0.2 and 0.9 +/- 0.5 respectively). A decrease of cellular accumulation of neutrophils and lymphocytes in the bronchoalveolar lavage (BAL) fluid was observed in infected mice treated with MMLA, especially at dosage of 10 mg/kg, given in a single dose intraperitoneally. In addition, BP-infected mice treated with MMLA (100 mg/kg, intraperitoneally) for 5 consecutive days showed higher mortality rate than untreated mice infected with B. pertussis, and the number of B. pertussis in lungs of mice treated with MMLA was significantly increased. However, MMLA treatment of infected mice had some effect on levels of IFN-gamma and nitrite/nitrate (end-stable products of NO) in the BAL fluid. This study indicates that NO may play a role either as microbiocidal agent or as a modulator of immune regulation, inasmuch as it may upregulate tissue inflammatory response to B. pertussis.

Animals↗