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1.
BMJ Open Qual ; 13(3)2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39117395

RESUMO

BACKGROUND: One of the biggest changes to primary care triggered by the COVID-19 pandemic was the rapid integration of virtual care (VC). VC offers benefits to patients and providers but implementation presents challenges. METHODS: This study is a secondary analysis of a 2021 quality improvement (QI) driven environmental scan comprising a survey and 1:1 interviews, at the Department of Family and Community Medicine at the University of Toronto. The scan aimed to understand the current and desired future use of VC at the 14 sites. RESULTS: The survey was completed by all sites between July and October 2021 and 1:1 interviews were conducted between October and November 2021 with 12 of the 14 site/QI leads. VC was seen as convenient and flexible, and as enabling continuity of care for patients who could not easily attend in-person. Factors enabling implementation of VC included leadership at both the system and local level; a shared understanding of VC on the part of providers, patients and clinical staff; and technological and administrative readiness. Challenges included the need for triage algorithms; incongruent expectations of VC by patients and providers; technology issues; increased administrative burden; and impacts on medical education. All anticipated that some degree of VC would continue in future. CONCLUSIONS: VC offered benefits but it also impacted clinical routines and administrative processes creating new forms of work for clinicians and staff. Patient education is needed to ensure that their expectations of VC align with those of providers. Research and QI efforts are required to optimise the use of VC in primary care.


Assuntos
COVID-19 , Atenção Primária à Saúde , Melhoria de Qualidade , Humanos , Atenção Primária à Saúde/estatística & dados numéricos , SARS-CoV-2 , Telemedicina , Inquéritos e Questionários , Pandemias , Ontário
3.
Bioorg Med Chem Lett ; 27(11): 2634-2640, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28416131

RESUMO

Hepatitis C virus (HCV) NS5B RNA-dependent RNA polymerase (RdRp) plays a central role in virus replication. NS5B has no functional equivalent in mammalian cells, and as a consequence is an attractive target for selective inhibition. This paper describes the discovery of a novel family of HCV NS5B non-nucleoside inhibitors inspired by the bioisosterism between sulfonamide and phosphonamide. Systematic structural optimization in this new series led to the identification of IDX375, a potent non-nucleoside inhibitor that is selective for genotypes 1a and 1b. The structure and binding domain of IDX375 were confirmed by X-ray co-crystalisation study.


Assuntos
Antivirais/química , Hepacivirus/enzimologia , Lactamas/química , Compostos Organofosforados/química , Proteínas não Estruturais Virais/antagonistas & inibidores , Regulação Alostérica , Animais , Antivirais/síntese química , Antivirais/metabolismo , Antivirais/farmacologia , Sítios de Ligação , Cristalografia por Raios X , Genótipo , Meia-Vida , Haplorrinos , Hepacivirus/genética , Hepacivirus/fisiologia , Humanos , Lactamas/farmacologia , Camundongos , Simulação de Dinâmica Molecular , Compostos Organofosforados/farmacologia , Estrutura Terciária de Proteína , Ratos , Relação Estrutura-Atividade , Sulfonamidas/química , Proteínas não Estruturais Virais/metabolismo , Replicação Viral/efeitos dos fármacos
4.
Bioorg Med Chem Lett ; 26(18): 4536-4541, 2016 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-27520942

RESUMO

The hepatitis C virus (HCV) NS5B RNA-dependent RNA polymerase (RdRp) plays a central role in virus replication. NS5B has no functional equivalent in mammalian cells and, as a consequence, is an attractive target for selective inhibition. This Letter describes the discovery of a new family of HCV NS5B non-nucleoside inhibitors, based on the bioisosterism between amide and phosphonamidate functions. As part of this program, SAR in this new series led to the identification of IDX17119, a potent non-nucleoside inhibitor, active on the genotypes 1b, 2a, 3a and 4a. The structure and binding domain of IDX17119 were confirmed by X-ray co-crystallization study.


Assuntos
Antivirais/farmacologia , Genótipo , Hepacivirus/efeitos dos fármacos , Proteínas não Estruturais Virais/antagonistas & inibidores , Sítio Alostérico , Antivirais/química , Antivirais/metabolismo , Cristalografia por Raios X , Relação Estrutura-Atividade , Proteínas não Estruturais Virais/metabolismo
5.
Future Med Chem ; 7(13): 1675-700, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26424162

RESUMO

BACKGROUND: Ribonucleoside analogs possessing a ß-methyl substituent at the 2'-position of the d-ribose moiety have been previously discovered to be potent and selective inhibitors of hepatitis C virus (HCV) replication, their triphosphates acting as alternative substrate inhibitors of the HCV RdRp NS5B. Results/methodology: In this article, the authors detail the synthesis, anti-HCV evaluation in cell-based replicon assays and structure-activity relationships of several phosphoramidate diester derivatives of 2'-C-methylguanosine (2'-MeG). CONCLUSION: The most promising compound, namely the O-[S-(hydroxyl)pivaloyl-2-thioethyl]{abbreviated as O-[(HO)tBuSATE)]} N-benzylamine phosphoramidate diester derivative (IDX184), was selected for further in vivo studies, and was the first clinical pronucleotide evaluated for the treatment of chronic hepatitis C up to Phase II trials.


Assuntos
Antivirais/síntese química , Antivirais/farmacologia , Descoberta de Drogas , Guanosina Monofosfato/análogos & derivados , Hepacivirus/efeitos dos fármacos , Hepatite C/tratamento farmacológico , Guanosina Monofosfato/síntese química , Guanosina Monofosfato/farmacologia , Humanos , Relação Estrutura-Atividade
6.
Bioorg Med Chem Lett ; 25(22): 5427-36, 2015 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-26410074

RESUMO

Exploration of the P2 region by mimicking the proline motif found in BILN2061 resulted in the discovery of two series of potent HCV NS3/4A protease inhibitors. X-ray crystal structure of the ligand in contact with the NS3/4A protein and modulation of the quinoline heterocyclic region by structure based design and modeling allowed for the optimization of enzyme potency and cellular activity. This research led to the selection of clinical candidate IDX320 having good genotype coverage and pharmacokinetic properties in various species.


Assuntos
Descoberta de Drogas , Hepacivirus/efeitos dos fármacos , Compostos Macrocíclicos/química , Compostos Macrocíclicos/farmacologia , Proteínas não Estruturais Virais/antagonistas & inibidores , Animais , Haplorrinos , Hepatócitos/enzimologia , Humanos , Concentração Inibidora 50 , Camundongos , Microssomos Hepáticos/enzimologia , Estrutura Molecular , Ratos , Ratos Sprague-Dawley , Inibidores de Serina Proteinase/síntese química , Inibidores de Serina Proteinase/química , Inibidores de Serina Proteinase/farmacologia , Proteínas não Estruturais Virais/química
7.
Bioorg Med Chem Lett ; 25(18): 3984-91, 2015 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-26231161

RESUMO

We disclose here the synthesis of a series of macrocyclic HCV protease inhibitors, where the homoserine linked together the quinoline P2' motif and the macrocyclic moiety. These compounds exhibit potent inhibitory activity against HCV NS3/4A protease and replicon cell based assay. Their enzymatic and antiviral activities are modulated by substitutions on the quinoline P2' at position 8 by methyl and halogens and by small heterocycles at position 2. The in vitro structure activity relationship (SAR) studies and in vivo pharmacokinetic (PK) evaluations of selected compounds are described herein.


Assuntos
Antivirais/síntese química , Antivirais/farmacologia , Hepacivirus/efeitos dos fármacos , Homosserina/farmacologia , Inibidores de Serina Proteinase/síntese química , Inibidores de Serina Proteinase/farmacologia , Proteínas não Estruturais Virais/antagonistas & inibidores , Antivirais/química , Relação Dose-Resposta a Droga , Hepacivirus/enzimologia , Homosserina/síntese química , Homosserina/química , Testes de Sensibilidade Microbiana , Estrutura Molecular , Inibidores de Serina Proteinase/química , Relação Estrutura-Atividade , Proteínas não Estruturais Virais/metabolismo
8.
Bioorg Med Chem Lett ; 24(18): 4444-4449, 2014 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-25155387

RESUMO

Structural homology between thrombin inhibitors and the early tetrapeptide HCV protease inhibitor led to the bioisosteric replacement of the P2 proline by a 2,4-disubstituted azetidine within the macrocyclic ß-strand mimic. Molecular modeling guided the design of the series. This approach was validated by the excellent activity and selectivity in biochemical and cell based assays of this novel series and confirmed by the co-crystal structure of the inhibitor with the NS3/4A protein (PDB code: 4TYD).


Assuntos
Azetidinas/farmacologia , Desenho de Fármacos , Inibidores de Serina Proteinase/farmacologia , Proteínas não Estruturais Virais/antagonistas & inibidores , Azetidinas/síntese química , Azetidinas/química , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Modelos Moleculares , Estrutura Molecular , Inibidores de Serina Proteinase/síntese química , Inibidores de Serina Proteinase/química , Relação Estrutura-Atividade , Proteínas não Estruturais Virais/metabolismo
10.
Med Lav ; 102(4): 350-61, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21834272

RESUMO

BACKGROUND: Since its foundation in 2002, the Italian Silica Network (NIS), a collaborative network of professionals and public authorities, has been engaged in several aspects of research, control, and prevention of silica exposure and effects, and also in support for compensation claims for silica-related occupational health effects in Italy. METHODS: We start with a report on the NIS point of view concerning the recent scientific results (from epidemiology and laboratory studies), including those carried out by NIS in cooperation with Italian universities and other public agencies. This is followed by a description of the data on silica exposure in different Italian workplaces and guidelines for the management of occupational exposure to silica, as developed by two model regional programmes for the ceramics industry, metal foundries and tunnel excavation. RESULTS: The NIS initiatives highlighted the persistence of workplace conditions posing a significant risk for silica-related health effects, particularly in small industries and workshops. Experimental work has also shown that a number of physical and chemical factors affect the bioreactivity of silica particles. CONCLUSION: Based on NIS experience, it appears clear that currently conditions exist in Italy so as to positively contribute to the WHO Programme for the eradication of silicosis and the other diseases related to silica exposure. In order to achieve this goal, a coordinated and wide-ranging effort is required to reduce the wide gap in specific prevention activities, particularly in small industries and workshops, where high levels of silica exposure sometimes occur.


Assuntos
Neoplasias Pulmonares/induzido quimicamente , Doenças Profissionais/induzido quimicamente , Exposição Ocupacional/efeitos adversos , Exposição Ocupacional/prevenção & controle , Dióxido de Silício/efeitos adversos , Carcinógenos , Humanos , Itália , Neoplasias Pulmonares/epidemiologia , Doenças Profissionais/epidemiologia , Saúde Ocupacional
14.
Nucleic Acids Symp Ser (Oxf) ; (52): 617-8, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18776531

RESUMO

A series of novel 4-fluoro-1H-pyrazole-3-carboxamide nucleoside analogues were synthesized and evaluated as potential inhibitors of RNA virus replication, including hepatitis C virus (HCV).


Assuntos
Antivirais/síntese química , Ribavirina/análogos & derivados , Antivirais/química , Antivirais/farmacologia , Hepacivirus/efeitos dos fármacos
15.
Antivir Chem Chemother ; 18(4): 225-42, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17907380

RESUMO

RNA viruses are the agents of numerous widespread and often severe diseases. Their unique RNA-dependent RNA polymerase (RDRP) is essential for replication and, thus, constitutes a valid target for the development of selective chemotherapeutic agents. In this regard, we have investigated sugar-modified ribonucleoside analogues as potential inhibitors of the RDRP. Title compounds retain 'natural' pyrimidine bases, but possess a beta-methyl substituent at the 2'-position of the D- or L-ribose moiety. Evaluation against a broad range of RNA viruses, either single-stranded positive (ssRNA+), single-stranded negative (ssRNA-) or double-stranded (dsRNA), revealed potent activities for D-2'-C-methyl-cytidine and -uridine against ssRNA+, and dsRNA viruses. None of the L-enantiomers were active. Moreover, the 5'-triphosphates of the active D-enantiomers were found to inhibit the bovine virus diarrhoea virus polymerase. Thus, the 2'-methyl branching of natural pyrimidine ribonucleosides transforms physiological molecules into potent, broad-spectrum antiviral agents that merit further development.


Assuntos
Antivirais/farmacologia , Nucleosídeos de Pirimidina/farmacologia , Vírus de RNA/efeitos dos fármacos , Vírus de RNA/fisiologia , Replicação Viral/efeitos dos fármacos , Animais , Antivirais/química , Linhagem Celular , Cricetinae , Cães , Haplorrinos , Humanos , Estrutura Molecular , Nucleosídeos de Pirimidina/química , Relação Estrutura-Atividade
16.
Antivir Chem Chemother ; 15(5): 269-79, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15535049

RESUMO

beta-L-2'-Deoxycytidine (beta-L-dC) is a potent, selective and specific anti-hepatitis B virus (HBV) agent. To improve its oral bioavailability, several derivatives involving sugar or base acylation, as well N4-derivatization with an N,N-(dimethylamino)methylene function, were synthesized. The physicochemical characteristics (including chemical stabilities, solubilities and distribution coefficient values) and pharmacokinetics of these compounds were determined and compared with those of the parent drug, beta-L-dC.


Assuntos
Antivirais/síntese química , Desoxicitidina/análogos & derivados , Desoxicitidina/síntese química , Vírus da Hepatite B/efeitos dos fármacos , Pró-Fármacos/síntese química , Acilação , Administração Oral , Animais , Antivirais/farmacocinética , Antivirais/farmacologia , Disponibilidade Biológica , Desoxicitidina/farmacocinética , Desoxicitidina/farmacologia , Haplorrinos , Vírus da Hepatite B/metabolismo , Testes de Sensibilidade Microbiana , Pró-Fármacos/farmacocinética , Pró-Fármacos/farmacologia , Solubilidade
17.
Med Lav ; 95(6): 465-74, 2004.
Artigo em Italiano | MEDLINE | ID: mdl-15732256

RESUMO

BACKGROUND: For a few years now in Italy there has been wide discussion on the advisability of developing health surveillance programmes for workers who were exposed to occupational carcinogens in the past (incompliance with Italian D.Lgs. 626/94, art. No. 69). The purpose of the present paper was to contribute to the discussion on operative guidelines for public or private Occupational Health Services intending to address this issue. METHODS: A cross-sectional survey was undertaken on former workers of a glass factory located in Leghorn, Italy. Six hundred and seventy-seven workers discharged in the period 1/1/1942 - 30/6/1992, with at least 1 year of service, resident in the area of Leghorn, were identified from the personnel records of the company and invited to medical examination at the local public Occupational Health Service. A structured questionnaire was developed in order to standardize the collection of occupational and health histories. RESULTS: 370 subjects were examined and for each of them occupational and health histories were collected. Occupational exposure to carcinogens in the factory in the last decades was reconstructed using the workers' occupational histories and the available plant records: 3 periods with different production activities (1942/49, 1950/69, 1970/92), and 4 main carcinogens (asbestos, PAH, silica and glass fibres) were identified. Thirty cancers were recorded and 10 of these were occupationally related. CONCLUSIONS: The health survey allowed occupational exposures to carcinogens to be defined in a factory where historical environmental data were not available. It was also possible to assess individual past occupational risk and provide information to each former worker on his risk, on available preventive measures, and on possible diagnostic, therapeutic and insurance procedures available in relation to diseases related to the different hazards. Via this survey it was also possible to identify and notify the Italian Institute of Insurance against Occupational Diseases and Accidents of 6 cases of bladder cancer, i.e., cancers with long survival that would be impossible to identify via current health data bases.


Assuntos
Amianto/efeitos adversos , Carcinógenos/efeitos adversos , Vidro , Nível de Saúde , Inquéritos Epidemiológicos , Indústrias , Exposição Ocupacional , Idoso , Humanos , Itália , Masculino
18.
J Med Chem ; 46(12): 2482-93, 2003 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-12773052

RESUMO

The potent anti-HIV-1 activities of L-737,126 (2) and PAS sulfones prompted us to design and test against HIV-1 in acutely infected MT-4 cells a number of novel 1- and 3-benzenesulfonylindoles. Indoles belonging to the 1-benzenesulfonyl series were found poorly or totally inactive. On the contrary, some of the 3-benzenesulfonyl derivatives turned out to be as potent as 2, being endowed with potencies in the low nanomolar concentration range. In particular, (2-methylphenyl)sulfonyl (72) and (3-methylphenyl)sulfonyl (73) derivatives showed EC(50) values of 1 nM. Introduction of two methyl groups at positions 3 and 5 of the phenyl ring of 2 furnished derivatives (80 and 83) which showed very potent and selective anti-HIV-1 activity not only against the wt strain, but also against mutants carrying NNRTI-resistant mutations at positions 103 and 181 of the reverse transcriptase gene.


Assuntos
Fármacos Anti-HIV/síntese química , Farmacorresistência Viral/genética , HIV-1/efeitos dos fármacos , Indóis/síntese química , Inibidores da Transcriptase Reversa/síntese química , Sulfonas/síntese química , Fármacos Anti-HIV/química , Fármacos Anti-HIV/farmacologia , Linhagem Celular , HIV-1/genética , Humanos , Indóis/química , Indóis/farmacologia , Mutação , Inibidores da Transcriptase Reversa/química , Inibidores da Transcriptase Reversa/farmacologia , Relação Estrutura-Atividade , Sulfonas/química , Sulfonas/farmacologia
19.
Nucleosides Nucleotides Nucleic Acids ; 21(10): 619-35, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12502279

RESUMO

A new class of acyclic nucleoside phosphonates PMAMG, PMAMA, PMAMC, and PMAMT (compounds 1, 2, 3 and 4) have been synthesized and tested in vitro against a wide variety of viruses, fungi and bacteria. PMAMG (1) was synthesized by the alkylation reaction of acetylguanine with the phosphonate side-chain, diisopropyl [[2-(bromomethyl)aziridin-1-yl]]methylphosphonate (9), followed by deesterification reaction in the presence of TMSBr. In similar way, PMAMA, PMAMC, and PMAMT were prepared.


Assuntos
Anti-Infecciosos/síntese química , Anti-Infecciosos/farmacologia , Aziridinas/síntese química , Aziridinas/farmacologia , Nucleosídeos/síntese química , Nucleosídeos/farmacologia , Organofosfonatos/síntese química , Organofosfonatos/farmacologia , Alquilação , Animais , Antibacterianos , Antivirais/síntese química , Antivirais/farmacologia , Linhagem Celular , Esterificação , Guanina/análogos & derivados , Humanos , Testes de Sensibilidade Microbiana , Shigella/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Streptococcaceae/classificação , Streptococcaceae/efeitos dos fármacos , Relação Estrutura-Atividade , Vírus/efeitos dos fármacos , Leveduras/efeitos dos fármacos
20.
Bioorg Med Chem ; 10(10): 3153-61, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12150860

RESUMO

3'-Deoxy-3'-C-CF3, 2',3'-dideoxy-3'-C-CF3 and 2',3'-unsaturated-3'-C-CF3 nucleoside derivatives of adenosine and cytidine have been synthesized. All these derivatives were prepared by glycosylation of adenine and uracil with a suitable peracylated 3-trifluoromethyl sugar precursor. The resulting protected nucleosides were subject to appropriate chemical modifications to afford the target nucleoside derivatives. Additionally, the chemical stability in acidic and neutral media of the 2',3'-dideoxy-3'-C-CF3 and 2',3'-unsaturated-3'-C-CF3 nucleoside derivatives of adenosine was compared to that of their parent nucleosides 2',3'-dideoxyadenosine (ddA) and 2',3'-dideoxy-2',3'-didehydroadenosine (d(4)A). Our results confirm that addition of a trifluoromethyl group at C-3' on such nucleoside derivatives appears to confer increased chemical stability toward acid-catalyzed cleavage of the glycosidic bond comparatively to their parent counterparts. When evaluated for their antiviral activity in cell culture experiments, two compounds, namely, 2',3'-dideoxy-3'-C-CF3-adenosine and 2',3'-dideoxy-2',3'-didehydro-3'-C-CF3-cytidine exhibited moderate anti-HBV activity with EC50 values of 10 and 5 microM, respectively.


Assuntos
Adenosina/análogos & derivados , Antivirais/síntese química , Citosina/análogos & derivados , Adenosina/síntese química , Adenosina/farmacologia , Antivirais/farmacologia , Clorofluorcarbonetos de Metano , Citosina/síntese química , Citosina/farmacologia , Estabilidade de Medicamentos , HIV-1/efeitos dos fármacos , Vírus da Hepatite B/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Relação Estrutura-Atividade , Células Tumorais Cultivadas
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