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1.
Artigo em Inglês | MEDLINE | ID: mdl-35954604

RESUMO

The expanded Theory of Planned Behavior (ETPB) was applied to examine undergraduates' environmental protection behaviors. Moral norms were applied into the model as the predictor of attitude, social norms and perceived behavioral control. The effects of different class standings were also examined. A questionnaire survey was conducted and 380 responses underwent data analysis using structural equation modelling. According to Model ETPB, perceived behavioral control and subjective norms were strongly affected by moral norms, while attitude was moderately affected by moral norms. Environmental protection behaviors was moderately affected by environmental protection intention, while environmental protection intention was moderately affected by perceived behavioral control which was the strongest predictor, followed by attitude and subjective norms. Invoking moral emotions through posters or peers leading by examples, which over time might internalize into moral norms, played an important role in positively affecting perceived behavioral control and subjective norms. This could be followed by simple and convenient programs creating a positive self-perception of the abilities to carry out environmental protection behaviors. When separated by class standings, perceived behavioral control was the strongest predictor for the freshmen class, while subjective norms were non-significant. For the class standing of sophomores and above, attitude was the strongest predictor.


Assuntos
Conservação dos Recursos Naturais , Intenção , Atitude , Humanos , Princípios Morais , Teoria Psicológica , Inquéritos e Questionários , Universidades
2.
Molecules ; 25(21)2020 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-33105798

RESUMO

Hypoxia is an adverse prognostic feature of solid cancers that may be overcome with hypoxia-activated prodrugs (HAPs). Tirapazamine (TPZ) is a HAP which has undergone extensive clinical evaluation in this context and stimulated development of optimized analogues. However the subcellular localization of the oxidoreductases responsible for mediating TPZ-dependent DNA damage remains unclear. Some studies conclude only nuclear-localized oxidoreductases can give rise to radical-mediated DNA damage and thus cytotoxicity, whereas others identify a broader role for endoplasmic reticulum and cytosolic oxidoreductases, indicating the subcellular location of TPZ radical formation is not a critical requirement for DNA damage. To explore this question in intact cells we engineered MDA-231 breast cancer cells to express the TPZ reductase human NADPH: cytochrome P450 oxidoreductase (POR) harboring various subcellular localization sequences to guide this flavoenzyme to the nucleus, endoplasmic reticulum, cytosol or inner surface of the plasma membrane. We show that all POR variants are functional, with differences in rates of metabolism reflecting enzyme expression levels rather than intracellular TPZ concentration gradients. Under anoxic conditions, POR expression in all subcellular compartments increased the sensitivity of the cells to TPZ, but with a fall in cytotoxicity per unit of metabolism (termed 'metabolic efficiency') when POR is expressed further from the nucleus. However, under aerobic conditions a much larger increase in cytotoxicity was observed when POR was directed to the nucleus, indicating very high metabolic efficiency. Consequently, nuclear metabolism results in collapse of hypoxic selectivity of TPZ, which was further magnified to the point of reversing O2 dependence (oxic > hypoxic sensitivity) by employing a DNA-affinic TPZ analogue. This aerobic hypersensitivity phenotype was partially rescued by cellular copper depletion, suggesting the possible involvement of Fenton-like chemistry in generating short-range effects mediated by the hydroxyl radical. In addition, the data suggest that under aerobic conditions reoxidation strictly limits the TPZ radical diffusion range resulting in site-specific cytotoxicity. Collectively these novel findings challenge the purported role of intra-nuclear reductases in orchestrating the hypoxia selectivity of TPZ.


Assuntos
Antineoplásicos/química , Hipóxia/tratamento farmacológico , NADPH-Ferri-Hemoproteína Redutase/genética , Pró-Fármacos/química , Tirapazamina/química , Antineoplásicos/farmacologia , Engenharia Celular , Hipóxia Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Membrana Celular/efeitos dos fármacos , Núcleo Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cobre/metabolismo , Dano ao DNA/efeitos dos fármacos , Dano ao DNA/genética , Humanos , Modelos Biológicos , NADPH-Ferri-Hemoproteína Redutase/metabolismo , NADPH-Ferri-Hemoproteína Redutase/ultraestrutura , Oxigênio/metabolismo , Pró-Fármacos/metabolismo , Tirapazamina/metabolismo
3.
AIDS ; 32(6): 699-708, 2018 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-29334544

RESUMO

OBJECTIVE: To define the relationships between molecular measures of viral persistence in blood (i.e., plasma viremia, cellular HIV-1 DNA, and mRNA) and expressed or inducible virus from resting CD4 T cells of individuals on suppressive antiretroviral therapy. DESIGN: We compared molecular measurements of HIV-1 in plasma and in uncultured peripheral blood mononuclear cells (PBMCs) to the levels of virions produced by either unstimulated or phorbol myristate acetate and ionomycin (PMA/iono)-stimulated PBMC or resting CD4 T cells from 21 donors on suppressive antiretroviral therapy. RESULTS: We found that unstimulated virion release from cultured resting CD4 T cells was positively correlated with the levels of plasma viremia in vivo (Spearman rho = 0.67, P = 0.0017). We also found that levels of both cellular HIV-1 DNA and unspliced HIV-1 mRNA per million uncultured PBMC were positively correlated with the levels of inducible virion release from both PMA/iono-stimulated PBMC (total HIV-1 DNA: rho = 0.64, P = 0.0017; unspliced HIV-1 RNA: rho = 0.77, P < 0.001) and PMA/iono-stimulated resting CD4 T cells (total HIV-1 DNA: rho = 0.75, P < 0.001; unspliced HIV-1 RNA: rho = 0.75, P < 0.001). CONCLUSION: These results show for the first time that there are strong associations between in-vivo measures of HIV-1 persistence and ex-vivo measures of spontaneous and inducible virus production from cultured PBMC and resting CD4 T cells. Findings from this study provide insight into the biology of HIV-1 persistence and suggest methods to guide the evaluation of clinical strategies to reduce the size of the viral reservoir.


Assuntos
Antirretrovirais/administração & dosagem , Biomarcadores/sangue , DNA Viral/sangue , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , RNA Viral/sangue , Resposta Viral Sustentada , Adulto , Idoso , Células Cultivadas , Estudos Transversais , Feminino , Humanos , Ionomicina/metabolismo , Leucócitos Mononucleares/virologia , Masculino , Pessoa de Meia-Idade , Acetato de Tetradecanoilforbol/metabolismo , Ativação Viral/efeitos dos fármacos
4.
Laryngoscope ; 127 Suppl 4: S1-S9, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28752518

RESUMO

OBJECTIVES/HYPOTHESIS: To evaluate the usefulness of elastic scattering spectroscopy (ESS) as a diagnostic adjunct to frozen section analysis in patients with diagnosed squamous cell carcinoma of the oral cavity. STUDY DESIGN: Prospective analytic study. METHODS: Subjects for this single institution, institutional review board-approved study were recruited from among patients undergoing surgical resection for squamous cell cancer of the oral cavity. A portable ESS device with a contact fiberoptic probe was used to obtain spectral signals. Four to 10 spectral readings were obtained on each subject from various sites including gross tumor and normal-appearing mucosa in the surgical margin. Each reading was correlated with the histopathologic findings of biopsies taken from the exact location of the spectral readings. A diagnostic algorithm based on multidimensional pattern recognition/machine learning was developed. Sensitivity and specificity, error rate, and area under the curve were used as performance metrics for tests involving classification between disease and nondisease classes. RESULTS: Thirty-four (34) subjects were enrolled in the study. One hundred seventy-six spectral data point/biopsy specimen pairs were available for analysis. ESS distinguished normal from abnormal tissue, with a sensitivity ranging from 84% to 100% and specificity ranging from 71% to 89%, depending on how the cutoff between normal and abnormal tissue was defined (i.e., mild, moderate, or severe dysplasia). There were statistically significant differences in malignancy scores between histologically normal tissue and invasive cancer and between noninflamed tissue and inflamed tissue. CONCLUSIONS: This is the first study to evaluate the effectiveness of ESS in guiding mucosal resection margins in oral cavity cancer. ESS provides fast, real-time assessment of tissue without the need for pathology expertise. ESS appears to be effective in distinguishing between normal mucosa and invasive cancer and between "normal" tissue (histologically normal and mild dysplasia) and "abnormal" tissue (severe dysplasia and carcinoma in situ) that might require further margin resection. Further studies, however, are needed with a larger sample size to validate these findings and to determine the effectiveness of ESS in distinguishing visibly and histologically normal tissue from visibly normal but histologically abnormal tissue. LEVEL OF EVIDENCE: NA Laryngoscope, 127:S1-S9, 2017.


Assuntos
Carcinoma de Células Escamosas/patologia , Margens de Excisão , Neoplasias Bucais/patologia , Análise Espectral/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , Carcinoma de Células Escamosas/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/cirurgia , Espalhamento de Radiação , Sensibilidade e Especificidade
5.
Nat Commun ; 8: 14432, 2017 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-28211448

RESUMO

G-quadruplex DNAs form four-stranded helical structures and are proposed to play key roles in different cellular processes. Targeting G-quadruplex DNAs for cancer treatment is a very promising prospect. Here, we show that CX-5461 is a G-quadruplex stabilizer, with specific toxicity against BRCA deficiencies in cancer cells and polyclonal patient-derived xenograft models, including tumours resistant to PARP inhibition. Exposure to CX-5461, and its related drug CX-3543, blocks replication forks and induces ssDNA gaps or breaks. The BRCA and NHEJ pathways are required for the repair of CX-5461 and CX-3543-induced DNA damage and failure to do so leads to lethality. These data strengthen the concept of G4 targeting as a therapeutic approach, specifically for targeting HR and NHEJ deficient cancers and other tumours deficient for DNA damage repair. CX-5461 is now in advanced phase I clinical trial for patients with BRCA1/2 deficient tumours (Canadian trial, NCT02719977, opened May 2016).


Assuntos
Proteína BRCA1/deficiência , Proteína BRCA2/deficiência , Benzotiazóis/farmacologia , Benzotiazóis/uso terapêutico , Quadruplex G , Naftiridinas/farmacologia , Naftiridinas/uso terapêutico , Neoplasias/tratamento farmacológico , Animais , Sequência de Bases , Benzoxazinas/farmacologia , Caenorhabditis elegans/efeitos dos fármacos , Linhagem Celular Tumoral , Instabilidade Cromossômica/genética , Dano ao DNA , Reparo do DNA/efeitos dos fármacos , Replicação do DNA/efeitos dos fármacos , DNA Ribossômico/genética , Feminino , Quadruplex G/efeitos dos fármacos , Genoma Humano , Genótipo , Recombinação Homóloga/efeitos dos fármacos , Humanos , Camundongos , Quinolonas/farmacologia , Saccharomyces cerevisiae/metabolismo , Transcrição Gênica/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
6.
J Virol ; 91(8)2017 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-28179531

RESUMO

Antiretroviral therapy can suppress HIV replication to undetectable levels but does not eliminate latent HIV, thus necessitating lifelong therapy. Recent efforts to target this persistent reservoir have focused on inducing the expression of latent HIV so that infected cells may be recognized and eliminated by the immune system. Toll-like receptor (TLR) activation stimulates antiviral immunity and has been shown to induce HIV from latently infected cells. Activation of TLR7 leads to the production of several stimulatory cytokines, including type I interferons (IFNs). In this study, we show that the selective TLR7 agonist GS-9620 induced HIV in peripheral blood mononuclear cells (PBMCs) from HIV-infected individuals on suppressive antiretroviral therapy. GS-9620 increased extracellular HIV RNA 1.5- to 2-fold through a mechanism that required type I IFN signaling. GS-9620 also activated HIV-specific T cells and enhanced antibody-mediated clearance of HIV-infected cells. Activation by GS-9620 in combination with HIV peptide stimulation increased CD8 T cell degranulation, production of intracellular cytokines, and cytolytic activity. T cell activation was again dependent on type I IFNs produced by plasmacytoid dendritic cells. GS-9620 induced phagocytic cell maturation and improved effector-mediated killing of HIV-infected CD4 T cells by the HIV envelope-specific broadly neutralizing antibody PGT121. Collectively, these data show that GS-9620 can activate HIV production and improve the effector functions that target latently infected cells. GS-9620 may effectively complement orthogonal therapies designed to stimulate antiviral immunity, such as therapeutic vaccines or broadly neutralizing antibodies. Clinical studies are under way to determine if GS-9620 can target HIV reservoirs.IMPORTANCE Though antiretroviral therapies effectively suppress viral replication, they do not eliminate integrated proviral DNA. This stable intermediate of viral infection is persistently maintained in reservoirs of latently infected cells. Consequently, lifelong therapy is required to maintain viral suppression. Ultimately, new therapies that specifically target and eliminate the latent HIV reservoir are needed. Toll-like receptor agonists are potent enhancers of innate antiviral immunity that can also improve the adaptive immune response. Here, we show that a highly selective TLR7 agonist, GS-9620, activated HIV from peripheral blood mononuclear cells isolated from HIV-infected individuals with suppressed infection. GS-9620 also improved immune effector functions that specifically targeted HIV-infected cells. Previously published studies on the compound in other chronic viral infections show that it can effectively induce immune activation at safe and tolerable clinical doses. Together, the results of these studies suggest that GS-9620 may be useful for treating HIV-infected individuals on suppressive antiretroviral therapy.


Assuntos
Infecções por HIV/virologia , HIV/imunologia , HIV/fisiologia , Fatores Imunológicos/farmacologia , Pteridinas/farmacologia , Receptor 7 Toll-Like/agonistas , Ativação Viral/efeitos dos fármacos , Antirretrovirais/uso terapêutico , Citotoxicidade Celular Dependente de Anticorpos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Diferenciação Celular/efeitos dos fármacos , Humanos , Interferon Tipo I/metabolismo , Ativação Linfocitária/efeitos dos fármacos , Fagócitos/efeitos dos fármacos , Fagócitos/fisiologia , RNA Viral/sangue , Carga Viral
7.
PLoS Pathog ; 12(4): e1005545, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27082643

RESUMO

Resting CD4+ T-cells harboring inducible HIV proviruses are a critical reservoir in antiretroviral therapy (ART)-treated subjects. These cells express little to no viral protein, and thus neither die by viral cytopathic effects, nor are efficiently cleared by immune effectors. Elimination of this reservoir is theoretically possible by combining latency-reversing agents (LRAs) with immune effectors, such as CD8+ T-cells. However, the relative efficacy of different LRAs in sensitizing latently-infected cells for recognition by HIV-specific CD8+ T-cells has not been determined. To address this, we developed an assay that utilizes HIV-specific CD8+ T-cell clones as biosensors for HIV antigen expression. By testing multiple CD8+ T-cell clones against a primary cell model of HIV latency, we identified several single agents that primed latently-infected cells for CD8+ T-cell recognition, including IL-2, IL-15, two IL-15 superagonists (IL-15SA and ALT-803), prostratin, and the TLR-2 ligand Pam3CSK4. In contrast, we did not observe CD8+ T-cell recognition of target cells following treatment with histone deacetylase inhibitors or with hexamethylene bisacetamide (HMBA). In further experiments we demonstrate that a clinically achievable concentration of the IL-15 superagonist 'ALT-803', an agent presently in clinical trials for solid and hematological tumors, primes the natural ex vivo reservoir for CD8+ T-cell recognition. Thus, our results establish a novel experimental approach for comparative evaluation of LRAs, and highlight ALT-803 as an LRA with the potential to synergize with CD8+ T-cells in HIV eradication strategies.


Assuntos
Antivirais/farmacologia , Linfócitos T CD4-Positivos/virologia , Infecções por HIV/imunologia , Proteínas/farmacologia , Linfócitos T Citotóxicos/imunologia , Latência Viral/efeitos dos fármacos , Ensaio de Imunoadsorção Enzimática , ELISPOT , Citometria de Fluxo , Humanos , Reação em Cadeia da Polimerase , Proteínas Recombinantes de Fusão , Ativação Viral/efeitos dos fármacos
8.
Ann Otol Rhinol Laryngol ; 125(6): 457-63, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26658070

RESUMO

OBJECTIVE: To evaluate the efficacy and utility of simulation of the Emergency Airway Response Team (EART) at a tertiary care hospital to improve team dynamics and confidence and knowledge in managing an emergency airway. METHODS: This was a descriptive, quantitative performance improvement study. From September 1, 2013, to December 1, 2013, 177 members of the EART from anesthesia, otolaryngology, trauma surgery, emergency medicine, ICU nursing, and respiratory therapy participated in emergency airway simulations. Team dynamics and confidence levels and knowledge of EART were assessed using pre-and post-simulation questionnaires. RESULTS: All participants regardless of their role, experience in the medical field, or any prior exposure to a difficult airway showed significant improvement in self-rated team participation and confidence and objective knowledge regarding EART after undergoing simulation. CONCLUSION: Our study highlights the efficacy and utility of simulation in assessing personnel team dynamics and confidence levels and knowledge of emergency airway scenarios. Practitioners in all fields and level of experience benefit in EART training and simulation. We hope that with this information, we will be able to conduct future studies on reduction of patient morbidity and mortality.


Assuntos
Manuseio das Vias Aéreas , Atitude do Pessoal de Saúde , Competência Clínica , Equipe de Respostas Rápidas de Hospitais , Intubação Intratraqueal , Treinamento por Simulação , Traqueotomia/educação , Anestesiologia , Protocolos Clínicos , Enfermagem de Cuidados Críticos , Educação Médica , Medicina de Emergência , Humanos , Otolaringologia , Papel Profissional , Melhoria de Qualidade , Terapia Respiratória , Traumatologia
9.
PLoS Pathog ; 11(11): e1005233, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26539983

RESUMO

HIV reservoirs and production of viral antigens are not eliminated in chronically infected participants treated with combination antiretroviral therapy (cART). Novel therapeutic strategies aiming at viral reservoir elimination are needed to address chronic immune dysfunction and non-AIDS morbidities that exist despite effective cART. The HIV envelope protein (Env) is emerging as a highly specific viral target for therapeutic elimination of the persistent HIV-infected reservoirs via antibody-mediated cell killing. Dual-Affinity Re-Targeting (DART) molecules exhibit a distinct mechanism of action via binding the cell surface target antigen and simultaneously engaging CD3 on cytotoxic T lymphocytes (CTLs). We designed and evaluated Env-specific DARTs (HIVxCD3 DARTs) derived from known antibodies recognizing diverse Env epitopes with or without broadly neutralizing activity. HIVxCD3 DARTs derived from PGT121, PGT145, A32, and 7B2, but not VRC01 or 10E8 antibodies, mediated potent CTL-dependent killing of quiescent primary CD4 T cells infected with diverse HIV isolates. Similar killing activity was also observed with DARTs structurally modified for in vivo half-life extension. In an ex vivo model using cells isolated from HIV-infected participants on cART, combinations of the most potent HIVxCD3 DARTs reduced HIV expression both in quiescent and activated peripheral blood mononuclear cell cultures isolated from HIV-infected participants on suppressive cART. Importantly, HIVxCD3 DARTs did not induce cell-to-cell virus spread in resting or activated CD4 T cell cultures. Collectively, these results provide support for further development of HIVxCD3 DARTs as a promising therapeutic strategy for targeting HIV reservoirs.


Assuntos
Linfócitos T CD4-Positivos/virologia , Infecções por HIV/imunologia , HIV-1/efeitos dos fármacos , Leucócitos Mononucleares/virologia , Linfócitos T Citotóxicos/virologia , Antígenos CD4/imunologia , Linfócitos T CD4-Positivos/imunologia , Anticorpos Anti-HIV/imunologia , Anticorpos Anti-HIV/uso terapêutico , Infecções por HIV/terapia , HIV-1/imunologia , Humanos , Leucócitos Mononucleares/imunologia , Linfócitos T Citotóxicos/imunologia
10.
Org Lett ; 17(2): 262-5, 2015 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-25560385

RESUMO

Screening of a marine natural products library afforded three new analogues of the tetronic acid containing polyketide abyssomicin family and identified abyssomicin 2 as a selective reactivator of latent HIV virus. Examination of the mode of action of this new latent HIV reactivating agent demonstrated that it functions via a distinct mechanism compared to that of existing reactivating agents and is effective at reactivating latent virus in a subset of primary patient cell lines.


Assuntos
Compostos Bicíclicos Heterocíclicos com Pontes/química , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Furanos/química , Infecções por HIV/tratamento farmacológico , HIV-1/efeitos dos fármacos , Policetídeos/química , Proteína Quinase C/química , Latência Viral/efeitos dos fármacos , Linhagem Celular , Inibidores de Histona Desacetilases/metabolismo , Inibidores de Histona Desacetilases/farmacologia , Humanos , Estrutura Molecular , Proteína Quinase C/metabolismo , Proteína Quinase C/farmacologia
11.
Otol Neurotol ; 35(10): 1825-34, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25393974

RESUMO

OBJECTIVE: Otologic trauma was the most common physical injury sustained after the April 15, 2013, Boston Marathon bombings. The goal of this study is to describe the resultant otologic morbidity and to report on early outcomes. STUDY DESIGN: Multi-institutional prospective cohort study. METHODS: Children and adults seen for otologic complaints related to the Boston Marathon bombings comprised the study population. Participants completed symptom assessments, quality-of-life questionnaires, and audiograms at initial and 6-month visits. Otologic evaluation and treatment, including tympanoplasty results, were reviewed. RESULTS: More than 100 patients from eight medical campuses have been evaluated for blast-related otologic injuries; 94 have enrolled. Only 7% had any otologic symptoms before the blasts. Ninety percent of hospitalized patients sustained tympanic membrane perforation. Proximity to blast (RR = 2.7, p < 0.01) and significant nonotologic injury (RR = 2.7, p < 0.01) were positive predictors of perforation. Spontaneous healing occurred in 38% of patients, and tympanoplasty success was 86%. After oral steroid therapy in eight patients, improvement in hearing at 2 and 4 kHz was seen, although changes did not reach statistical significance. Hearing loss, tinnitus, hyperacusis, and difficulty hearing in noise remain persistent and, in some cases, progressive complaints for patients. Otologic-specific quality of life was impaired in this population. CONCLUSION: Blast-related otologic injuries constitute a major source of ongoing morbidity after the Boston Marathon bombings. Continued follow-up and care of this patient population are warranted.


Assuntos
Traumatismos por Explosões/complicações , Explosões , Perda Auditiva/etiologia , Hiperacusia/etiologia , Zumbido/etiologia , Perfuração da Membrana Timpânica/etiologia , Corticosteroides/uso terapêutico , Adulto , Traumatismos por Explosões/psicologia , Traumatismos por Explosões/terapia , Criança , Estudos de Coortes , Feminino , Perda Auditiva/psicologia , Testes Auditivos , Humanos , Hiperacusia/psicologia , Masculino , Estudos Prospectivos , Qualidade de Vida/psicologia , Inquéritos e Questionários , Zumbido/psicologia , Perfuração da Membrana Timpânica/psicologia , Perfuração da Membrana Timpânica/terapia , Timpanoplastia
12.
PLoS Pathog ; 10(4): e1004071, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24722454

RESUMO

Persistent latent reservoir of replication-competent proviruses in memory CD4 T cells is a major obstacle to curing HIV infection. Pharmacological activation of HIV expression in latently infected cells is being explored as one of the strategies to deplete the latent HIV reservoir. In this study, we characterized the ability of romidepsin (RMD), a histone deacetylase inhibitor approved for the treatment of T-cell lymphomas, to activate the expression of latent HIV. In an in vitro T-cell model of HIV latency, RMD was the most potent inducer of HIV (EC50 = 4.5 nM) compared with vorinostat (VOR; EC50 = 3,950 nM) and other histone deacetylase (HDAC) inhibitors in clinical development including panobinostat (PNB; EC50 = 10 nM). The HIV induction potencies of RMD, VOR, and PNB paralleled their inhibitory activities against multiple human HDAC isoenzymes. In both resting and memory CD4 T cells isolated from HIV-infected patients on suppressive combination antiretroviral therapy (cART), a 4-hour exposure to 40 nM RMD induced a mean 6-fold increase in intracellular HIV RNA levels, whereas a 24-hour treatment with 1 µM VOR resulted in 2- to 3-fold increases. RMD-induced intracellular HIV RNA expression persisted for 48 hours and correlated with sustained inhibition of cell-associated HDAC activity. By comparison, the induction of HIV RNA by VOR and PNB was transient and diminished after 24 hours. RMD also increased levels of extracellular HIV RNA and virions from both memory and resting CD4 T-cell cultures. The activation of HIV expression was observed at RMD concentrations below the drug plasma levels achieved by doses used in patients treated for T-cell lymphomas. In conclusion, RMD induces HIV expression ex vivo at concentrations that can be achieved clinically, indicating that the drug may reactivate latent HIV in patients on suppressive cART.


Assuntos
Linfócitos T CD4-Positivos/virologia , Depsipeptídeos/farmacologia , Regulação Viral da Expressão Gênica/efeitos dos fármacos , Infecções por HIV/tratamento farmacológico , HIV-1/fisiologia , Inibidores de Histona Desacetilases/farmacologia , Modelos Biológicos , Ativação Viral/efeitos dos fármacos , Latência Viral/efeitos dos fármacos , Antibióticos Antineoplásicos/farmacocinética , Antibióticos Antineoplásicos/farmacologia , Linfócitos T CD4-Positivos/metabolismo , Células Cultivadas , Depsipeptídeos/farmacocinética , Relação Dose-Resposta a Droga , Feminino , Infecções por HIV/virologia , Inibidores de Histona Desacetilases/farmacocinética , Histona Desacetilases/metabolismo , Humanos , Memória Imunológica/efeitos dos fármacos , Isoenzimas/metabolismo , Masculino
13.
J Nat Prod ; 77(3): 618-24, 2014 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-24495105

RESUMO

An extract of Humicola fuscoatra (UCSC strain no. 108111A) was shown to reactivate latent HIV-1 expression in an in vitro model of central memory CD4+ T cells. We report the bioassay-guided isolation and structure determination of several resorcyclic acid lactones, including four known compounds, radicicol (1, aka. monorden) and pochonins B (2), C (3), and N (4), and three new analogues, radicicols B-D (5-7). Compounds 1-3 and 5 showed moderate activities in the memory T cell model of HIV-1 latency. Radicicol (1) displayed lower potency in reactivating latent HIV-1 (EC50 = 9.1 µM) relative to the HDAC inhibitors apicidin (EC50 = 0.3 µM), romidepsin (EC50 = 0.003 µM), and SAHA (EC50 = 0.6 µM); however, it achieved equivalent maximum efficacy relative to the positive control compounds (98% of SAHA and romidepsin).


Assuntos
Ascomicetos/química , Produtos Biológicos/farmacologia , Linfócitos T CD4-Positivos/virologia , HIV-1/fisiologia , Inibidores de Histona Desacetilases/farmacologia , Lactonas/química , Macrolídeos/farmacologia , Produtos Biológicos/química , Infecções por HIV/virologia , Inibidores de Histona Desacetilases/química , Humanos , Lactonas/farmacologia , Macrolídeos/química , Biologia Marinha , Modelos Biológicos , Estrutura Molecular , Latência Viral/efeitos dos fármacos
14.
PLoS One ; 8(9): e74163, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24040198

RESUMO

HIV-1 integrase (IN) is the target for two classes of antiretrovirals: i) the integrase strand-transfer inhibitors (INSTIs) and ii) the non-catalytic site integrase inhibitors (NCINIs). NCINIs bind at the IN dimer interface and are thought to interfere primarily with viral DNA (vDNA) integration in the target cell by blocking IN-vDNA assembly as well as the IN-LEDGF/p75 interaction. Herein we show that treatment of virus-producing cells, but not of mature virions or target cells, drives NCINI antiviral potency. NCINIs target an essential late-stage event in HIV replication that is insensitive to LEDGF levels in the producer cells. Virus particles produced in the presence of NCINIs displayed normal Gag-Pol processing and endogenous reverse transcriptase activity, but were defective at initiating vDNA synthesis following entry into the target cell. NCINI-resistant virus carrying a T174I mutation in the IN dimer interface was less sensitive to the compound-induced late-stage effects, including the reverse transcription block. Wild-type, but not T174I virus, produced in the presence of NCINIs exhibited striking defects in core morphology and an increased level of IN oligomers that was not observed upon treatment of mature cell-free particles. Collectively, these results reveal that NCINIs act through a novel mechanism that is unrelated to the previously observed inhibition of IN activity or IN-LEDGF interaction, and instead involves the disruption of an IN function during HIV-1 core maturation and assembly.


Assuntos
DNA Viral/antagonistas & inibidores , Inibidores de Integrase de HIV/farmacologia , Integrase de HIV/genética , Transcriptase Reversa do HIV/antagonistas & inibidores , HIV-1/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Linhagem Celular Tumoral , DNA Viral/genética , Farmacorresistência Viral , Expressão Gênica , Genes Reporter , Vetores Genéticos , Integrase de HIV/metabolismo , Inibidores de Integrase de HIV/química , Transcriptase Reversa do HIV/genética , Transcriptase Reversa do HIV/metabolismo , HIV-1/genética , HIV-1/crescimento & desenvolvimento , HIV-1/metabolismo , Interações Hospedeiro-Patógeno , Humanos , Luciferases/genética , Luciferases/metabolismo , Mutação , Linfócitos T/efeitos dos fármacos , Linfócitos T/patologia , Linfócitos T/virologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Vírion/efeitos dos fármacos , Vírion/genética , Montagem de Vírus/efeitos dos fármacos , Integração Viral/efeitos dos fármacos
15.
J Allergy Clin Immunol ; 132(2): 455-62, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23810153

RESUMO

BACKGROUND: Thymic stromal lymphopoietin (TSLP) pathway blockade is a potential strategy for asthma treatment because the main activities of TSLP are activation of myeloid dendritic cells (mDCs) and modulation of cytokine production by mast cells. TSLP-activated mDCs prime the differentiation of naive T cells into inflammatory TH2 cells. OBJECTIVE: We sought to investigate mechanisms underlying the development of allergic lung inflammation in cynomolgus monkeys using gene expression profiling and to assess the effect of thymic stromal lymphopoietin receptor (TSLPR) blockade in this model. METHODS: An mAb against human TSLPR was generated and confirmed to be cross-reactive to cynomolgus monkey. Animals were dosed weekly with either vehicle or anti-TSLPR mAb for 6 weeks, and their responses to allergen challenge at baseline, week 2, and week 6 were assessed. RESULTS: After 6 weeks of treatment, anti-TSLPR mAb-treated animals showed reduced bronchoalveolar lavage (BAL) fluid eosinophil counts, reduced airway resistance in response to allergen challenge, and reduced IL-13 cytokine levels in BAL fluid compared with values seen in vehicle-treated animals. Expression profiling of BAL fluid cells collected before and after challenge showed a group of genes upregulated by allergen challenge that strongly overlapped with 11 genes upregulated in dendritic cells (DCs) when in vitro stimulated by TSLP (TSLP-DC gene signature). The number of genes differentially expressed in response to challenge was reduced in antibody-treated animals after 6 weeks relative to vehicle-treated animals. Expression of the TSLP-DC gene signature was also significantly reduced in antibody-treated animals. CONCLUSION: These results demonstrate promising efficacy for TSLPR blockade in an allergic lung inflammation model in which TSLP activation of mDCs might play a key role.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Asma/terapia , Modelos Animais de Doenças , Hipersensibilidade/terapia , Inflamação/terapia , Receptores de Citocinas/antagonistas & inibidores , Animais , Anticorpos Monoclonais/imunologia , Asma/imunologia , Cricetinae , Citocinas/imunologia , Citocinas/metabolismo , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/imunologia , Feminino , Humanos , Hipersensibilidade/imunologia , Inflamação/imunologia , Macaca fascicularis/imunologia , Receptores de Citocinas/imunologia , Células Th2/imunologia , Células Th2/metabolismo , Linfopoietina do Estroma do Timo
16.
Chin Med J (Engl) ; 122(15): 1743-8, 2009 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-19781318

RESUMO

BACKGROUND: Post-operation pain is a very subjective phenomenon. The aim of this study was to find out the effects of acupuncture or electro-acupuncture on post-cesarean pain. METHODS: Sixty women, who had had spinal anesthesia during cesarean section at the Department of Obstetrics of China Medical University Hospital, were randomly assigned to the control group, the acupuncture group, and the electro-acupuncture group. After the operation, we applied subjects with acupuncture or electro-acupuncture on the bilateral acupuncture point, San Yin Jiao (Sp6), and the patient controlled analgesia (PCA). The first time of requesting morphine, the frequency of PCA demands in 24 hours, and the doses of PCA used were recorded double blindly. In addition, monitoring the subjects' vital signs, the opioid-related side effects, and the pain scores was done. RESULTS: The results showed that the acupuncture group and the electro-acupuncture group could delay the time of requesting morphine up to 10 - 11 minutes when compared with the control group. The total dose of PCA used within the first 24 hours was 30% - 35% less in the acupuncture group and the electro-acupuncture group when compared with the control group, which was indicated in statistical significance. However, there was no significant difference between the acupuncture group and the electro-acupuncture group. The electro-acupuncture group's and the acupuncture group's pain scores were lower than the control group's within the first 2 hours. Both were statistically significant. However, two hours later, there were no significant differences of the visual analogue scale (VAS) scores between either of the treatment groups and the control group. Finally, the incidence of opioid-related side effects, such as dizziness, was less in the acupuncture group and electro-acupuncture group than in the control group. CONCLUSIONS: This study shows that the application of acupuncture and electro-acupuncture could definitely delay the time of requesting pain relief medication after cesarean section and decrease the PCA doses used within the first 24 hours.


Assuntos
Terapia por Acupuntura/métodos , Cesárea , Dor Pós-Operatória/terapia , Adulto , Analgésicos/uso terapêutico , Feminino , Humanos , Masculino , Morfina/uso terapêutico , Dor Pós-Operatória/tratamento farmacológico , Gravidez
17.
Acupunct Electrother Res ; 29(1-2): 83-95, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15382791

RESUMO

If acupuncture is able to prevent hypertrophy of the heart, it could therefore prevent the heart from overloading and thus prevent heart failure or sudden death. We therefore studied the effects of acupuncture on blood pressure and cardiac muscle cells. Rats with spontaneous hypertension were divided into three acupuncture treatment groups and one non-treatment group. The treatment groups were classified as sham acupoint, Yanglingquan (GB. 34) and Quchi (LI. 11) groups. The measurements recorded included changes in tail pressure, femoral arterial pressure, left ventricular weight (LVW), whole heart weight (WHW), body weight (BW), LVW/BW and WHW/BW ratios and the size of the cardiac muscle cells. The results showed that femoral arterial pressure of subjects which were needled on the selected points for 3 days dropped. Acupuncture at these two acupoints seemed to improve the condition of hypertension in a short period of time. Significant changes in the femoral arterial pressure were observed in all subjects when they were treated for 6 days. In the two acupoint groups, the LVW/BW and the WHW/BW ratios did not change significantly. Cardiac muscle cells reduced in size in the Yanglingquan (GB. 34) treatment groups. This indicates that the Yanglingquan (GB. 34) points not only can lower blood pressure, but also prevent hypertrophy of cardiac muscle cells in spontaneous hypertensive rats (SHR). Therefore, acupuncture could be a good treatment modality for hypertension and hypertrophy of the heart.


Assuntos
Acupuntura/métodos , Hipertensão/terapia , Miocárdio/patologia , Animais , Pressão Sanguínea , Peso Corporal , Coração/fisiologia , Masculino , Tamanho do Órgão , Ratos , Ratos Endogâmicos SHR , Ratos Wistar
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