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1.
Neurol Sci ; 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38277051

RESUMO

BACKGROUND: Autologous haematopoietic stem cell transplantation (AHSCT) is a highly effective one-off treatment for relapsing-remitting multiple sclerosis (RR-MS), potentially representing an optimal front-loading strategy for costs. OBJECTIVE: Exploring cost/effectiveness of AHSCT and high-efficacy disease-modifying treatments (HE-DMTs) in RR-MS, estimating costs at our centre in Italy, where National Health Service (NHS) provides universal health coverage. METHODS: Costs (including drugs, inpatient/outpatient management) for treatment with AHSCT and HE-DMTs were calculated as NHS expenditures over 2- and 5-year periods. Cost-effectiveness for each treatment was estimated as "cost needed to treat" (CNT), i.e. expense to prevent relapses, progression, or disease activity (NEDA) in one patient over n-years, retrieving outcomes from published studies. RESULTS: Costs of AHSCT and HE-DMTs were similar over 2 years, whereas AHSCT was cheaper than most HE-DMTs over 5 years (€46 600 vs €93 800, respectively). When estimating cost-effectiveness of treatments, over 2 years, mean CNT of HE-DMTs for NEDA was twofold that of AHSCT, whereas it was similar for relapses and disability. Differences in CNT were remarkable over 5 years, especially for NEDA, being mean CNT of HE-DMTs €382 800 vs €74 900 for AHSCT. CONCLUSIONS: AHSCT may be highly cost-effective in selected aggressive RR-MS. Besides priceless benefits for treated individuals, cost-savings generated by AHSCT may contribute to improving healthcare assistance at a population level.

2.
Pathog Dis ; 75(6)2017 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-28637198

RESUMO

Despite the availability of several anti-retrovirals, there is still an urgent need for developing novel therapeutic strategies and finding new drugs against underexplored HIV-1 targets. Among them, there are the HIV-1 reverse transcriptase (RT)-associated ribonuclease H (RNase H) function and the cellular α-glucosidase, involved in the control mechanisms of N-linked glycoproteins formation in the endoplasmic reticulum. It is known that many natural compounds, such as pentacyclic triterpenes, are a promising class of HIV-1 inhibitors. Hence, here we tested the pentacyclic triterpene Lupeol, showing that it inhibits the HIV-1 RT-associated RNase H function. We then performed combination studies of Lupeol and the active site RNase H inhibitor RDS1759, and blind docking calculations, demonstrating that Lupeol binds to an HIV-1 RT allosteric pocket. On the bases of these results and searching for potential multitarget active drug supplement, we also investigated the anti-HIV-1 activity of Hemidesmus indicus, an Ayurveda medicinal plant containing Lupeol. Results supported the potential of this plant as a valuable multitarget active drug source. In fact, by virtue of its numerous active metabolites, H. indicus was able to inhibit not only the RT-associated RNase H function, but also the HIV-1 RT-associated RNA-dependent DNA polymerase activity and the cellular α-glucosidase.


Assuntos
Fármacos Anti-HIV/farmacologia , Inibidores Enzimáticos/farmacologia , Transcriptase Reversa do HIV/antagonistas & inibidores , Hemidesmus/química , Triterpenos Pentacíclicos/farmacologia , Ribonuclease H/antagonistas & inibidores , Sítio Alostérico , Fármacos Anti-HIV/química , Fármacos Anti-HIV/isolamento & purificação , Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Regulação da Expressão Gênica , Transcriptase Reversa do HIV/química , Transcriptase Reversa do HIV/genética , Transcriptase Reversa do HIV/metabolismo , HIV-1/efeitos dos fármacos , HIV-1/enzimologia , HIV-1/crescimento & desenvolvimento , Interações Hospedeiro-Patógeno , Humanos , Células Jurkat , Simulação de Acoplamento Molecular , Triterpenos Pentacíclicos/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Domínios e Motivos de Interação entre Proteínas , Estrutura Secundária de Proteína , Ribonuclease H/química , Ribonuclease H/genética , Ribonuclease H/metabolismo , alfa-Glucosidases/genética , alfa-Glucosidases/metabolismo
3.
Phytomedicine ; 23(12): 1383-1391, 2016 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-27765358

RESUMO

BACKGROUND: Despite the availability of effective antiretroviral therapies, drugs for HIV-1 treatment with new mode of action are still needed. An innovative approach is aimed to identify dual HIV-1 inhibitors, small molecules that can inhibit two viral functions at the same time. Rhubarb, originated from Rheum palmatum L. and Rheum officinale Baill., is one of the earliest and most commonly used medicinal plants in Traditional Chinese Medicine (TCM) practice. We wanted to explore TCM for the identification of new chemical scaffolds with dual action abilities against HIV-1. METHODS: R. palmatum L. and R. officinale Baill. extracts along with their main single isolated constituents anthraquinone derivatives were tested on both HIV-1 Reverse Transcriptase (RT)-associated DNA Polymerase (RDDP) and Ribonuclease H (RNase H) activities in biochemical assays. Active compounds were then assayed for their effects on HIV-1 mutated RTs, integrase (IN) and viral replication. RESULTS: Both R. palmatum L. and R. officinale Baill. extracts inhibited the HIV-1 RT-associated RNase H activity. Among the isolated constituents, Sennoside A and B were effective on both RDDP and RNase H RT-associated functions in biochemical assays. Sennoside A was less potent when tested on K103N, Y181C, Y188L, N474A and Q475A mutated RTs, suggesting the involvement of two RT binding sites for its antiviral activity. Sennoside A affected also HIV-1 IN activity in vitro and HIV-1 replication in cell-based assays. Viral DNA production and time of addition studies showed that Sennoside A targets the HIV-1 reverse transcription process. CONCLUSION: Sennoside A is a new scaffold for the development of HIV-1 dual RT inhibitors.


Assuntos
Fármacos Anti-HIV/farmacologia , Infecções por HIV/virologia , HIV-1/efeitos dos fármacos , Extratos Vegetais/farmacologia , Rheum/química , Extrato de Senna/farmacologia , Replicação Viral/efeitos dos fármacos , Antraquinonas/farmacologia , Infecções por HIV/tratamento farmacológico , Integrase de HIV/metabolismo , Transcriptase Reversa do HIV/metabolismo , Medicina Tradicional Chinesa , Inibidores da Transcriptase Reversa/farmacologia , Ribonuclease H/metabolismo , Senosídeos , Especificidade da Espécie
5.
Bioconjug Chem ; 27(1): 247-56, 2016 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-26666402

RESUMO

The Nucleocapsid protein NCp7 (NC) is a nucleic acid chaperone responsible for essential steps of the HIV-1 life cycle and an attractive candidate for drug development. NC destabilizes nucleic acid structures and promotes the formation of annealed substrates for HIV-1 reverse transcription elongation. Short helical nucleic acid segments bordered by bulges and loops, such as the Trans-Activation Response element (TAR) of HIV-1 and its complementary sequence (cTAR), are nucleation elements for helix destabilization by NC and also preferred recognition sites for threading intercalators. Inspired by these observations, we have recently demonstrated that 2,6-disubstituted peptidyl-anthraquinone-conjugates inhibit the chaperone activities of recombinant NC in vitro, and that inhibition correlates with the stabilization of TAR and cTAR stem-loop structures. We describe here enhanced NC inhibitory activity by novel conjugates that exhibit longer peptidyl chains ending with a conserved N-terminal lysine. Their efficient inhibition of TAR/cTAR annealing mediated by NC originates from the combination of at least three different mechanisms, namely, their stabilizing effects on nucleic acids dynamics by threading intercalation, their ability to target TAR RNA substrate leading to a direct competition with the protein for the same binding sites on TAR, and, finally, their effective binding to the NC protein. Our results suggest that these molecules may represent the stepping-stone for the future development of NC-inhibitors capable of targeting the protein itself and its recognition site in RNA.


Assuntos
Antraquinonas/farmacologia , Repetição Terminal Longa de HIV , Produtos do Gene gag do Vírus da Imunodeficiência Humana/antagonistas & inibidores , Produtos do Gene gag do Vírus da Imunodeficiência Humana/metabolismo , Antraquinonas/química , Antraquinonas/metabolismo , Sítios de Ligação , Lisina/química , Ácidos Nucleicos/química , RNA Viral/metabolismo , Produtos do Gene gag do Vírus da Imunodeficiência Humana/química
6.
Cells ; 3(2): 386-417, 2014 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-24805990

RESUMO

Through the combined action of ubiquitinating and deubiquitinating enzymes, conjugation of ubiquitin to a target protein acts as a reversible post-translational modification functionally similar to phosphorylation. Indeed, ubiquitination is more and more recognized as a central process for the fine regulation of many cellular pathways. Due to their nature as obligate intracellular parasites, viruses rely on the most conserved host cell machineries for their own replication. Thus, it is not surprising that members from almost every viral family are challenged by ubiquitin mediated mechanisms in different steps of their life cycle and have evolved in order to by-pass or exploit the cellular ubiquitin conjugating system to maximize their chance to establish a successful infection. In this review we will present several examples of the complex interplay that links viruses and the ubiquitin conjugation machinery, with a special focus on the mechanisms evolved by the human immunodeficiency virus to escape from cellular restriction factors and to exit from infected cells.

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