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1.
Bioorg Med Chem Lett ; 23(11): 3354-7, 2013 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-23639543

RESUMO

Ribonucleoside phosphonate analogues containing 2'-α-fluoro modifications were synthesized and their potency evaluated against HCV RNA polymerase. The diphosphophosphonate (triphosphate equivalent) adenine and cytidine analogues displayed potent inhibition of the HCV polymerase in the range of 1.9-2.1 µM, but only modest cell-based activity in the HCV replicon. Pro-drugs of the parent nucleoside phosphonates improved the cell-based activity.


Assuntos
Antivirais/química , RNA Polimerases Dirigidas por DNA/antagonistas & inibidores , Flúor/química , Hepacivirus/enzimologia , Organofosfonatos/química , Ribonucleosídeos/química , Antivirais/síntese química , Antivirais/farmacologia , Linhagem Celular , RNA Polimerases Dirigidas por DNA/metabolismo , Avaliação Pré-Clínica de Medicamentos , Humanos , Organofosfonatos/síntese química , Organofosfonatos/farmacologia , Replicação Viral/efeitos dos fármacos
2.
J Am Chem Soc ; 132(30): 10248-50, 2010 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-20662502

RESUMO

Enantioselective (formal) aza-Diels-Alder reactions between acylhydrazones and non-Danishefsky-type dienes have been developed. The reactions are promoted by a simple and economical chiral silicon Lewis acid and are typically conducted at ambient temperature. Both glyoxylate- and aliphatic aldehyde-derived hydrazones may be employed, as may variously substituted dienes, leading to the synthesis of a diverse array of tetrahydropyridines with good to excellent levels of enantioselectivity.


Assuntos
Hidrazonas/química , Polienos/química , Hidrazonas/síntese química , Polienos/síntese química , Piridinas/síntese química , Piridinas/química , Estereoisomerismo
3.
J Expo Sci Environ Epidemiol ; 30(3): 436-447, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31959901

RESUMO

While residential energy and ventilation standards aim to improve the energy performance and indoor air quality (IAQ) of homes, their combined impact across diverse residential activities and housing environments has not been well-established. This study demonstrates the insights that a recently-developed, freely-available coupled IAQ-energy modeling platform can provide regarding the energy and IAQ trade-offs of weatherization (i.e., sealing and insulation) and ventilation retrofits in multifamily housing across varied indoor occupant activity and mechanical ventilation scenarios in Boston, MA. Overall, it was found that combined weatherization and improved ventilation recommended by design standards could lead to both energy savings and IAQ-related benefits; however, ventilation standards may not be sufficient to protect against IAQ disbenefits for residents exposed to strong indoor sources (e.g., heavy cooking or smoking) and could lead to net increases in energy costs (e.g., due to the addition of continuous outdoor air ventilation). The modeling platform employed in this study is flexible and can be applied to a wide range of building typologies, retrofits, climates, and indoor occupant activities; therefore, it stands as a valuable tool for identifying cost-effective interventions that meet both energy efficiency and ventilation standards and improve IAQ across diverse housing populations.


Assuntos
Poluição do Ar em Ambientes Fechados/estatística & dados numéricos , Simulação por Computador , Habitação , Poluição do Ar em Ambientes Fechados/análise , Boston , Culinária , Humanos , Ventilação/normas , Tempo (Meteorologia)
4.
Bioorg Med Chem ; 17(4): 1739-46, 2009 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-19179082

RESUMO

A diphosphate of a novel cyclopentyl based nucleoside phosphonate with potent inhibition of HIV reverse transcriptase (RT) (20, IC(50)=0.13 microM) has been discovered. In cell culture the parent phosphonate diacid 9 demonstrated antiviral activity EC(50)=16 microM, within two-fold of GS-9148, a prodrug of which is currently under clinical investigation, and within 5-fold of tenofovir (PMPA). In vitro cellular metabolism studies using 9 confirmed that the active diphosphate metabolite is produced albeit at a lower efficiency relative to GS-9148.


Assuntos
Fármacos Anti-HIV/síntese química , Fármacos Anti-HIV/farmacologia , Nucleosídeos/síntese química , Organofosfonatos/síntese química , Inibidores da Transcriptase Reversa/síntese química , Linhagem Celular Tumoral , Desenho de Fármacos , Transcriptase Reversa do HIV/antagonistas & inibidores , Transcriptase Reversa do HIV/química , Humanos , Modelos Moleculares , Estrutura Molecular , Nucleosídeos/química , Nucleosídeos/farmacologia , Organofosfonatos/química , Organofosfonatos/farmacologia , Pró-Fármacos/síntese química , Pró-Fármacos/farmacocinética , Pró-Fármacos/farmacologia , Inibidores da Transcriptase Reversa/química , Inibidores da Transcriptase Reversa/uso terapêutico , Relação Estrutura-Atividade
5.
Tetrahedron ; 64(29): 7008-7014, 2008 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-22593605

RESUMO

Several heterocycles such as furanones, pyrrolones, and indolizines, which are of pharmacological importance, are easily accessed via the Pt(II)-catalyzed heterocyclization/1,2-migration of propargylic ketols or hydroxy imine derivatives. This method sidesteps the challenges of traditional heteroaromatic oxygenation strategies such as regioselectivity and functional group tolerance in the syntheses of these heterocycles.

6.
Psychol Serv ; 10(3): 265-275, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23244028

RESUMO

This study investigated the effectiveness of telephone-delivered cognitive-behavioral therapy (T-CBT) in the management of chronic pain with older military veterans enrolled in VA primary-care clinics. We conducted a randomized clinical trial comparing T-CBT with telephone-delivered pain education (T-EDU). A total of 98 military veterans with chronic pain were enrolled in the study and randomized into one of two treatment conditions. Study participants were recruited from primary-care clinics at an urban VA medical center and affiliated VA community-based outpatient clinics (CBOCs). Pain management outcomes were measured at midtreatment (10 weeks), posttreatment (20 weeks), 3-month follow-up (32 weeks), and 6-month follow-up (46 weeks). No significant differences were found between the two treatment groups on any of the outcome measures. Both treatment groups reported small but significant increases in level of physical and mental health, and reductions in pain and depressive symptoms. Improvements in all primary outcome measures were mediated by reductions in catastrophizing. Telephone-delivered CBT and EDU warrant further study as easily accessible interventions for rural-living older individuals with chronic pain.


Assuntos
Dor Crônica/terapia , Terapia Cognitivo-Comportamental/métodos , Manejo da Dor/métodos , Educação de Pacientes como Assunto/métodos , Telefone , Idoso , Dor Crônica/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pacientes Ambulatoriais/psicologia , Manejo da Dor/psicologia , Atenção Primária à Saúde/métodos , Inquéritos e Questionários , Resultado do Tratamento , Saúde da População Urbana , Veteranos/psicologia , Saúde dos Veteranos
7.
Influenza Other Respir Viruses ; 7(5): 666-75, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23552014

RESUMO

BACKGROUND: We investigated the roles of Toll-like receptors (TLRs) in naturally occurring influenza. METHODS: A prospective, case - control study was conducted. Adults hospitalized with virologically confirmed influenza A infections (onset <48 hours, before treatment) were compared with age-/gender-matched controls. TLRs (2, 3, 4, 7, 8, 9) expression in monocytes and dendritic cells (DCs - total, myeloid, plasmacytoid) was quantitated using flow cytometry. Gene expression of RLRs (RIG-1, MDA-5) was evaluated using real-time PCR. Concomitant signaling molecules expression, plasma cytokine/chemokine concentrations, and respiratory tract viral loads were measured. PBMCs were cultured and stimulated ex vivo with TLR-specific ligands for cytokine responses. RESULTS: Forty two patients with influenza (24 A/H3N2, 18 A/H1N1pdm09) and 20 controls were studied. Patients' mean age was 68 ± 16 years; 81% had respiratory/cardiovascular complications. There were increased cellular expressions of TLR9, TLR8, TLR3, and TLR7 during influenza; TLR2 and TLR4 were suppressed. Results were similar for both virus strains. Higher TLR expression levels at presentation significantly correlated with lower viral loads (Spearman's rho: -0.46 to -0.69 for TLR9, TLR8, and TLR3; P-values <0.05). Multivariate regression models (adjusted for age, comorbidity, disease severity, time from onset) confirmed their independent associations. Increased signaling molecules (phospho-MAPKs, IκB) and inflammatory cytokines (IL-6, sTNFR-1, CCL2/MCP-1; CXCL10/IP-10, IFN-γ) correlated with increased TLR expression. RLRs were upregulated simultaneously. PBMCs of patients with influenza showed significant, dynamic changes in their cytokine responses upon TLR stimulation, compared with controls. CONCLUSIONS: Our results suggest that TLRs play an important role in early, innate viral inhibition in naturally occurring influenza. Inflammatory cytokine responses are concomitantly induced. These findings support investigation of TLR targeting as a novel intervention approach for prophylaxis against influenza.


Assuntos
Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Vírus da Influenza A Subtipo H3N2/isolamento & purificação , Influenza Humana/imunologia , Receptores Toll-Like/imunologia , Adulto , Idoso , Estudos de Casos e Controles , Citocinas/genética , Citocinas/imunologia , Células Dendríticas/imunologia , Feminino , Hospitalização , Humanos , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H3N2/genética , Influenza Humana/genética , Influenza Humana/virologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Receptores Toll-Like/genética
8.
Psychol Addict Behav ; 26(2): 358-63, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21707127

RESUMO

The purpose of this study was to investigate expectancies regarding the interaction between cigarette smoking and use of alcohol among alcohol-dependent smokers in early recovery, using the Nicotine and Other Substances Interaction Expectancies Questionnaire (NOSIE). Participants were 162 veterans, 97% male, with a mean age of 50 years, enrolled in a clinical trial aimed at determining the efficacy of an intensive smoking cessation intervention versus usual care. At baseline, participants were assessed on measures of smoking behavior, abstinence thoughts about alcohol and tobacco use, symptoms of depression, and smoking-substance use interaction expectancies. In addition, biologically verified abstinence from tobacco and alcohol was assessed at 26 weeks. Participants reported that they expected smoking to have less of an impact on substance use than substance use has on smoking (p < .001). Severity of depressive symptoms was significantly associated with the expectancy that smoking provides a way of coping with the urge to use other substances (p < .01). The expectation that smoking increases substance urges/use was predictive of prospectively measured and biologically verified abstinence from smoking at 26 weeks (p < .03). The results add to our knowledge of smoking-substance use interaction expectancies among alcohol-dependent smokers in early recovery and will inform the development of more effective counseling interventions for concurrent alcohol and tobacco use disorders.


Assuntos
Transtornos Relacionados ao Uso de Álcool/psicologia , Conhecimentos, Atitudes e Prática em Saúde , Motivação , Abandono do Hábito de Fumar/psicologia , Fumar/psicologia , Inquéritos e Questionários , Adaptação Psicológica , Transtornos Relacionados ao Uso de Álcool/reabilitação , Depressão/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Análise de Regressão , Índice de Gravidade de Doença , Fumar/terapia , Resultado do Tratamento
9.
Drug Alcohol Depend ; 122(3): 186-94, 2012 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-22014532

RESUMO

INTRODUCTION: The purpose of this study was to investigate the efficacy of an intensive tobacco cessation intervention for alcohol-dependent smokers in early recovery. METHODS: A total of 162 alcohol-dependent smokers were randomized to either intensive intervention for smoking cessation or usual care. The intensive intervention consisted of 16 sessions of individual cognitive behavior therapy (CBT) and combination nicotine replacement therapy that lasted 26 weeks. Usual care involved referral to a free-standing smoking cessation program that provided smoking cessation counseling of varying duration and guideline-concordant medications. The primary cessation outcome was verified 7-day point prevalence abstinence (PPA) at 12, 26, 38, and 52 weeks. RESULTS: At 12 and 26 weeks, the verified 7-day point-prevalence quit rate was significantly higher for the intensive intervention group than for the usual care group (both p=0.03). However, the quit rates for the two treatment groups were not significantly different at 38 or 52 weeks. Verified 30-day alcohol abstinence rates were not significantly different for the two treatment groups at any of the follow-up assessments. CONCLUSIONS: The intensive smoking cessation intervention yielded a higher short-term smoking quit rate without jeopardizing sobriety. A chronic care model might facilitate maintenance of smoking cessation during the first year of alcohol treatment and perhaps for longer periods of time. It is hoped that studies such as this will inform the development of more effective interventions for concurrent alcohol and tobacco use disorders.


Assuntos
Alcoolismo/terapia , Abandono do Hábito de Fumar/métodos , Fumar/terapia , Tabagismo/terapia , Adulto , Alcoolismo/epidemiologia , Alcoolismo/psicologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Fumar/epidemiologia , Fumar/psicologia , Abandono do Hábito de Fumar/psicologia , Fatores de Tempo , Tabagismo/epidemiologia , Tabagismo/psicologia , Resultado do Tratamento
10.
PLoS One ; 6(10): e26050, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22022504

RESUMO

BACKGROUND: Studying cytokine/chemokine responses in severe influenza infections caused by different virus subtypes may improve understanding on pathogenesis. METHODS: Adults hospitalized for laboratory-confirmed seasonal and pandemic 2009 A/H1N1 (pH1N1) influenza were studied. Plasma concentrations of 13 cytokines/chemokines were measured at presentation and then serially, using cytometric-bead-array with flow-cytometry and ELISA. PBMCs from influenza patients were studied for cytokine/chemokine expression using ex-vivo culture (Whole Blood Assay,±PHA/LPS stimulation). Clinical variables were prospectively recorded and analyzed. RESULTS: 63 pH1N1 and 53 seasonal influenza patients were studied. pH1N1 patients were younger (mean±S.D. 42.8±19.2 vs 70.5±16.7 years), and fewer had comorbidities. Respiratory/cardiovascular complications were common in both groups (71.4% vs 81.1%), although severe pneumonia with hypoxemia (54.0% vs 28.3%) and ICU admissions (25.4% vs 1.9%) were more frequent with pH1N1. Hyperactivation of the proinflammatory cytokines IL-6, CXCL8/IL-8, CCL2/MCP-1 and sTNFR-1 was found in pH1N1 pneumonia (2-15 times normal) and in complicated seasonal influenza, but not in milder pH1N1 infections. The adaptive-immunity (Th1/Th17)-related CXCL10/IP-10, CXCL9/MIG and IL-17A however, were markedly suppressed in severe pH1N1 pneumonia (2-27 times lower than seasonal influenza; P-values<0.01). This pattern was further confirmed with serial measurements. Hypercytokinemia tended to be sustained in pH1N1 pneumonia, associated with a slower viral clearance [PCR-negativity: day 3-4, 55% vs 85%; day 6-7, 67% vs 100%]. Elevated proinflammatory cytokines, particularly IL-6, predicted ICU admission (adjusted OR 12.6, 95%CI 2.6-61.5, per log(10)unit increase; P = 0.002), and correlated with fever, tachypnoea, deoxygenation, and length-of-stay (Spearman's rho, P-values<0.01) in influenza infections. PBMCs in seasonal influenza patients were activated and expressed cytokines ex vivo (e.g. IL-6, CXCL8/IL-8, CCL2/MCP-1, CXCL10/IP-10, CXCL9/MIG); their 'responsiveness' to stimuli was shown to change dynamically during the illness course. CONCLUSIONS: A hyperactivated proinflammatory, but suppressed adaptive-immunity (Th1/Th17)-related cytokine response pattern was found in severe pH1N1 pneumonia, different from seasonal influenza. Cytokine/immune-dysregulation may be important in its pathogenesis.


Assuntos
Citocinas/sangue , Hospitalização/estatística & dados numéricos , Vírus da Influenza A Subtipo H1N1/fisiologia , Influenza Humana/sangue , Influenza Humana/epidemiologia , Pandemias/estatística & dados numéricos , Estações do Ano , Adulto , Quimiocinas/biossíntese , Quimiocinas/sangue , China/epidemiologia , Citocinas/biossíntese , Feminino , Humanos , Influenza Humana/imunologia , Influenza Humana/virologia , Leucócitos Mononucleares/imunologia , Masculino
11.
Environ Sci Technol ; 40(6): 1799-805, 2006 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-16570600

RESUMO

Assessment of secondhand tobacco smoke exposure using nicotine as a tracer or biomarker is affected by sorption of the alkaloid to indoor surfaces and by its long-term re-emission into the gas phase. However, surface chemical interactions of nicotine have not been sufficiently characterized. Here, the reaction of ozone with nicotine sorbed to Teflon and cotton surfaces was investigated in an environmental chamber by monitoring nicotine desorption over a week following equilibration in dry or humid air (approximately 0% or 65-70% RH, respectively). The Teflon and cotton surfaces had N2-BET surface areas of 0.19 and 1.17 m2 g(-1), and water mass uptakes (at 70% RH) of 0 and 7.1% respectively. Compared with dry air baseline levels in the absence of O3, gas-phase nicotine concentrations decreased by 2 orders of magnitude for Teflon after 50 h at 20-45 ppb O3, and by a factor of 10 for cotton after 100 h with 13-15 ppb O3. The ratios of pseudo first-order rate constants for surface reaction (r) to long-term desorption (k) were r/k = 3.5 and 2.0 for Teflon and cotton surfaces, respectively. These results show that surface oxidation was competitive with desorption. Hence, oxidative losses could significantly reduce long-term re-emissions of nicotine from indoor surfaces. Formaldehyde, N-methylformamide, nicotinaldehyde, and cotinine were identified as oxidation products, indicating that the pyrrolidinic N was the site of electrophilic attack by O3. The presence of water vapor had no effect on the nicotine-O3 reaction on Teflon surfaces. By contrast, nicotine desorption from cotton in humid air was unaffected by the presence of ozone. These observations are consistent with complete inhibition of ozone-nicotine surface reactions in an aqueous surface film present in cotton but not in Teflon surfaces.


Assuntos
Poluentes Atmosféricos/análise , Fibra de Algodão , Nicotina/análise , Ozônio/análise , Politetrafluoretileno/química , Absorção , Poluição do Ar em Ambientes Fechados/análise , Aldeídos/química , Formaldeído/química , Formamidas/química , Modelos Biológicos , Nicotina/química , Nitrogênio/química , Oxirredução , Ozônio/química , Fatores de Tempo , Volatilização
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