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61.
Riccardo Dolcetti Paola Zancai Roberta Cariati Mauro Boiocchi 《Leukemia & lymphoma》1998,29(3):269-281
Retinoids have been shown to be effective in the chemoprevention and treatment of certain human malignancies. In this review, we will summarize our recent results concerning the effects of retinoids on the proliferation and differentiation of Epstein-Barr virus (EBV)-immortalized lymphoblastoid B-cell lines (LCLs), an in vitro model of EBV-related lymphoproliferative disorders arising in immunosuppressed hosts. Retinoids proved to be powerful inhibitors of the proliferation of EBV-infected LCLs in vitro, with 13-cis-retinoic acid (RA), all-trans-RA, and 9-cis-RA being the most effective compounds. Of note, retinoid-induced growth arrest in vitro appears irreversible at drug concentrations (10--6 mol/L) which may be reached in man after oral systemic therapy. The antiproliferative activity exerted by retinoids on LCLs is a generalized phenomenon usually associated with a progressive accumulation in G0/G1 phases of treated cells. The strong upregulation of p27Kipl invariably observed in cells exposed to retinoids may contribute to the decreased number of cycling cells, probably by inhibiting the transition from the G1 to S phase. Moreover, we obtained evidence indicating that the antiproliferative effects of retinoids are not dependent on the induction of terminal differentiation of EBV-immortalized B lymphocytes. In fact, the modifications induced by retinoids relative to LCL morphology, phenotype (downregulation of CD19, HLA-DR, and s-Ig, and upregulation of CD38 and c-Ig), and IgM production were highly variable among the lines tested and often only slightly relevant. Finally, the antiproliferative activity exerted by retinoids on LCLs is not mediated by a direct modulation of viral latent antigens, since EBNA-2 and LMP-1 downregulation was a late event detected only in some cell lines. These results indicate that retinoids may be useful in the medical treatment of EBV-related lymphoproliferative disorders of immunosuppressed patients, particularly in the earlier phases of these diseases. 相似文献
62.
Bottoni Ferdinando Cereda Matteo Secondi Roberta Bochicchio Sara Staurenghi Giovanni 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2018,256(4):675-682
Graefe's Archive for Clinical and Experimental Ophthalmology - To evaluate the clinical outcomes of vitrectomy with induction of posterior vitreous detachment for the treatment of optic disc... 相似文献
63.
Alessandra Vergori Antonio Boschini Stefania Notari Patrizia Lorenzini Concetta Castilletti Francesca Colavita Giulia Matusali Eleonora Tartaglia Roberta Gagliardini Andrea Boschi Eleonora Cimini Markus Maeurer Pierluca Piselli Leila Angeli Andrea Antinori Chiara Agrati Enrico Girardi 《Viruses》2022,14(7)
The main aim of this study was to describe the clinical and immunological outcomes, as well as the inflammatory profile, of patients with advanced HIV in an assisted-living facility in which an outbreak of SARS-CoV-2 occurred. SARS-CoV-2 humoral and specific T-cell response were analyzed in patients with HIV infection and COVID-19; as a secondary objective of the analysis, levels of the inflammatory markers (IL-1β, IL-6, IL-8, and TNFα) were tested in the HIV/COVID-19 group, in HIV-positive patients without COVID-19, and in HIV-negative patients with mild/moderate COVID-19. Antibody kinetics and ability to neutralize SARS-CoV-2 were evaluated by ELISA assay, as well as the inflammatory cytokines; SARS-CoV-2 specific T-cell response was quantified by ELISpot assay. Mann–Whitney or Kruskal–Wallis tests were used for comparisons. Thirty patients were included with the following demographics: age, 57 years old (IQR, 53–62); 76% male; median HIV duration of infection, 18 years (15–29); nadir of CD4, 57/mmc (23–100) current CD4 count, 348/mmc (186–565). Furthermore, 83% had at least one comorbidity. The severity of COVID-19 was mild/moderate, and the overall mortality rate was 10% (3/30). Additionally, 90% of patients showed positive antibody titers and neutralizing activity, with a 100% positive SARS-CoV-2 specific T-cell response over time, suggesting the ability to induce an effective specific immunity. Significantly higher levels of IL-6, IL-8, and TNF-α in COVID-19 without HIV vs. HIV/COVID-19 patients (p < 0.05) were observed. HIV infection did not seem to negatively impact COVID-19-related inflammatory state and immunity. Further data are mandatory to evaluate the persistence of these immunity and its ability to expand after exposure and/or vaccination. 相似文献
64.
Claudia Fumarola Mara A. Bonelli Pier Giorgio Petronini Roberta R. Alfieri 《Biochemical pharmacology》2014
While PI3K/AKT/mTOR pathway is altered in a variety of cancers including non small cell lung cancer, abnormalities in this pathway are more common in squamous cell lung carcinoma than in adenocarcinoma of the lung. Moreover, aberrant activation of PI3K/AKT/mTOR pathway is one of the mechanisms of acquired resistance to EGFR-TK inhibitors in patients with adenocarcinoma carrying EGFR activating mutations. 相似文献
65.
Roberta Cassano Teresa Ferrarelli Maria Vittoria Mauro Paolina Cavalcanti Nevio Picci 《Drug delivery》2016,23(3):1037-1046
The present article reports the preparation, characterization and performance evaluation of solid lipid nanoparticles (SLNs) based on polyoxyethylene-40 stearate (PEG-40 stearate) for the administration of antifungal agents such as ketoconazole and clotrimazole. These nanoparticles could be useful in the treatment of vaginal infections sustained by Candida albicans. In particular, PEG-40 stearate was made to react with acryloyl chloride in order to introduce an easily polymerizable moiety for the creation of a second shell and to ensure a slow drug release. In addition, the differences on the release profiles between PEG-40 stearate-based nanoparticles, PEG-40 stearate acrylate based and polymerized ones, were analyzed under conditions, simulating the typical environment of Candida albicans infection. Then, the antifungal activity of nanoparticles was also evaluated in terms of minimal inhibitory concentration. Moreover, the nanoparticles were submitted to in vitro studies for evaluating the drug permeability at the site of action. Results indicated that the obtained particles are potentially useful for the treatment of vaginal infections sustained by Candida albicans. 相似文献
66.
Lambertini E Piva R Khan MT Lampronti I Bianchi N Borgatti M Gambari R 《International journal of oncology》2004,24(2):419-423
67.
Roberto Orecchia Umberto Veronesi Patrick Maisonneuve Viviana Enrica Galimberti Roberta Lazzari Paolo Veronesi Barbara Alicja Jereczek-Fossa Federica Cattani Claudia Sangalli Alberto Luini Pietro Caldarella Marco Venturino Daniele Sances Stefano Zurrida Giuseppe Viale Maria Cristina Leonardi Mattia Intra 《The lancet oncology》2021,22(5):597-608
68.
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70.
Lee TK Wang W O'Brien KF Johnke RM Wang T Allison RR Diaz AL 《Phytotherapy research : PTR》2008,22(12):1614-1622
To explore the radioprotective effect of a standardized North American ginseng extract (NAGE) on human peripheral blood lymphocytes (PBL), a micronuclei (MN) assay was conducted in PBL obtained from 12 volunteers. NAGE (50-1000 microg/mL) and WR-1065 (1 mM and 3 mM) were applied to PBL cultures at 0 h and 90 min post-irradiation. It was found that (1) the baseline MN yield of PBL ranged from 14.4 +/- 1.5 to 15.9 +/- 1.5 per 1000 binucleated cells (p > 0.05); after irradiation (1 Gy and 2 Gy), the MN yield increased sharply; (2) MN yields declined with increasing concentrations of NAGE and WR-1065. Even at 90 min post-irradiation of 1 Gy, the maximum level of MN reduction rate caused by NAGE and WR-1065 was 53.8% and 59.2%, respectively; after 2 Gy irradiation, it was 37.3% and 42%, respectively; (3) the MN distribution in PBL followed a non-Poisson distribution in all cases; and (4) both NAGE and WR-1065 showed no significant effect on the proliferation index of lymphocytes. The results indicate that NAGE is a relatively non-toxic natural product, which can be administered as a dietary supplement and has the potential to be a radiation countermeasure. 相似文献