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1.
Sci Rep ; 12(1): 21415, 2022 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-36496466

RESUMO

Several of Kahneman and Tversky's seminal works in the 1970s found evidence of the importance of framing in decision making under risk. They hypothesized that imaginability (visual imagery ability) may play an important role in the evaluation of subjective probabilities. However, the impact of visual imagery ability on choice under risk has not yet been explored. This is the main purpose of our study. In an online experiment, we collected participants' visual imagery ability using the Vividness of Visual Imagery Questionnaire and their risk attitude using two choice-based risk elicitation tasks. Participants made their risk decisions either in an environment where risk was visualized (visual frame) or not (non-visual frame), and were randomly assigned to one of the two decision frames. Our results suggest that neither visual imagery ability nor decision frame has a substantial impact on risk attitude.


Assuntos
Atitude , Imagens, Psicoterapia , Humanos , Inquéritos e Questionários , Probabilidade , Imaginação
2.
J Cancer Res Clin Oncol ; 146(7): 1801-1811, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32435894

RESUMO

PURPOSE: Oral mucositis is a debilitating inflammatory disorder observed in patients undergoing active cancer treatment, particularly cancer of the head and neck region. A key pathway believed to be involved in the pathogenesis of oral mucositis is the formation of reactive oxygen species (ROS). The identification of compounds that can inhibit this pathway may therefore be of benefit in treating this disorder. The kava plant (Piper methysticum) contains various constituents, including flavokawain A (FKA), flavokawain B (FKB), yangonin, methysticin and kavain. These constituents are known to be biologically active and possess anti-oxidative properties. This study therefore focused on examining these constituents for their effect on ROS formation in an in vitro oral mucositis model. METHODS: Cell proliferation was assessed in normal oral keratinocytes (OKF6) treated with and without kava constituents, namely FKA, FKB, yangonin, methysticin and kavain using an MTS in vitro assay. Oxidative stress was assessed by co-treating and pre-treating OKF6 cells with H2O2. The effects were quantified by analysis of ROS production, using a CM-H2DCFDA assay. RESULTS: Pre-treatment of cells for 24 h with 2.5 µg/ml kavain and 5 µg/ml FKA demonstrated a significant protective anti-oxidative effect. Similarly, FKB at a concentration of 2.5 µg/ml, demonstrated a trend of ROS reduction but was observed to be cytotoxic at concentrations greater than 5 µg/ml. Reduction in ROS production by methysticin and yangonin was compromised by their cell cytotoxicity. CONCLUSION: This was the first study to identify the anti-oxidative effects and safety of FKA and kavain with regard to oral keratinocytes, highlighting their potential use in the development of a preventative treatment for oral mucositis.


Assuntos
Kava/química , Extratos Vegetais/farmacologia , Substâncias Protetoras/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Linhagem Celular Tumoral , Células Cultivadas , Humanos , Peróxido de Hidrogênio/metabolismo , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/química , Substâncias Protetoras/química , Piranos/farmacologia , Pironas/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Estomatite/tratamento farmacológico , Estomatite/etiologia
3.
JACC Cardiovasc Interv ; 11(22): 2326-2334, 2018 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-30466832

RESUMO

OBJECTIVES: This study sought to report the 1-year safety and efficacy outcomes in the FORWARD (CoreValve Evolut R FORWARD) study following transcatheter aortic valve replacement (TAVR) with the next-generation Evolut R device (Medtronic, Minneapolis, Minnesota) in routine clinical practice. BACKGROUND: The FORWARD study reported low incidences of mortality, disabling stroke, and significant paravalvular leak following TAVR in routine clinical practice at 30 days. Longer-term results in large patient populations with the Evolut R self-expanding, repositionable transcatheter heart valve (THV) are lacking. METHODS: This was a prospective, single-arm, multinational, multicenter, observational study investigating efficacy and safety following TAVR with the next-generation self-expanding THV. Between January and December 2016, 1,040 patients underwent attempted implant of the Evolut R self-expanding repositionable valve at 53 sites worldwide. An independent Clinical Events Committee adjudicated safety endpoints based on Valve Academic Research Consortium-2 definitions. An independent echocardiographic core laboratory evaluated all echocardiograms. RESULTS: The mean age was 81.8 ± 6.2 years, 64.8% were women, and patients had a mean Society of Thoracic Surgeons Predicted Risk of Mortality score of 5.5 ± 4.5% and EuroSCORE II of 5.7 ± 5.0%. The 1-year all-cause mortality rate was 8.9%, with a cardiovascular mortality rate of 6.9%. At 1 year, the incidence of disabling stroke was 2.1%, and a pacemaker was implanted in 19.7% of patients. The incidence of more than mild paravalvular leak was 1.2%. CONCLUSIONS: The FORWARD study demonstrated good safety and efficacy profiles for the next-generation Evolut R THV up to 1-year follow-up, with very low mortality and adverse events. (CoreValve Evolut R FORWARD Study [FORWARD]; NCT02592369).


Assuntos
Estenose da Valva Aórtica/cirurgia , Valva Aórtica/cirurgia , Próteses Valvulares Cardíacas , Substituição da Valva Aórtica Transcateter/instrumentação , Idoso , Idoso de 80 Anos ou mais , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/fisiopatologia , Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/mortalidade , Estenose da Valva Aórtica/fisiopatologia , Feminino , Hemodinâmica , Humanos , Incidência , Masculino , Complicações Pós-Operatórias/mortalidade , Vigilância de Produtos Comercializados , Estudos Prospectivos , Desenho de Prótese , Recuperação de Função Fisiológica , Sistema de Registros , Medição de Risco , Fatores de Risco , Fatores de Tempo , Substituição da Valva Aórtica Transcateter/efeitos adversos , Substituição da Valva Aórtica Transcateter/mortalidade , Resultado do Tratamento
4.
J Thorac Cardiovasc Surg ; 156(4): 1368-1377.e5, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29778342

RESUMO

OBJECTIVES: The study objectives were to evaluate the safety, effectiveness, and hemodynamic performance of a new stented bovine pericardial aortic valve. METHODS: This trial enrolled patients with symptomatic moderate or severe aortic stenosis or chronic, severe aortic regurgitation. We assessed death, valve-related adverse events, functional recovery, and hemodynamic performance at discharge, 3 to 6 months, and 1 year, as required by the US Food and Drug Administration for regulatory approval. The primary analysis compared late linearized rates of valve-related adverse events after implantation with Food and Drug Administration-specified objective performance criteria to determine whether the adverse event rates associated with the valve are within acceptable limits. Adverse events included thromboembolism, thrombosis, all and major hemorrhage, all and major paravalvular leak, and endocarditis. RESULTS: The primary analysis included 864 patients who received an implant and 904.1 valve-years of follow-up. A total of 577 patients completed the 1-year evaluation. The primary end point was met for death, thromboembolism, thrombosis, all and major paravalvular leak, and endocarditis, but not for all and major hemorrhage. At 1 year, freedom from all death and from valve-related death was 96.4% and 99.7%, respectively. From baseline to 1 year, New York Heart Association class changed as follows: I, 10.8% to 73.7%; II, 48.9% to 22.6%; III, 38.0% to 3.5%; and IV, 2.3% to 0.2%. Effective orifice area increased from 0.9 ± 0.5 to 1.5 ± 0.4 (P < .0001), and mean aortic gradient decreased from 42.7 ± 16.5 to 12.5 ± 4.3 (P < .0001). CONCLUSIONS: This analysis of a new stented bovine pericardial aortic valve demonstrated low overall mortality and valve-related adverse events, and hemodynamic performance comparable to that of other surgical aortic valves.


Assuntos
Valva Aórtica/cirurgia , Bioprótese , Implante de Prótese de Valva Cardíaca , Próteses Valvulares Cardíacas , Idoso , Insuficiência da Valva Aórtica/cirurgia , Estenose da Valva Aórtica/cirurgia , Feminino , Implante de Prótese de Valva Cardíaca/instrumentação , Implante de Prótese de Valva Cardíaca/métodos , Implante de Prótese de Valva Cardíaca/mortalidade , Humanos , Masculino , Estudos Prospectivos
5.
Eur J Cardiothorac Surg ; 52(3): 425-431, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28475690

RESUMO

OBJECTIVES: We assessed the safety, effectiveness and haemodynamic performance of a new bovine stented aortic valve bioprosthesis (Avalus™). METHODS: The PERIGON Pivotal Trial is a prospective, non-randomized, multicentre study. Subjects had symptomatic moderate or severe aortic stenosis or chronic, severe aortic regurgitation. Death, valve-related adverse events (AEs), functional recovery and haemodynamic performance were assessed at discharge, 3-6 months and 1 year. The primary analysis compared 'late' (>30 days post-implant) linearized rates of valve-related thromboembolism, thrombosis, all and major haemorrhage, all and major paravalvular leak (PVL) and endocarditis after implantation with objective performance criteria (OPC) for AEs, in accordance with EN ISO 5840:2009. We hypothesized that the upper 95% confidence bounds of the true linearized AE rates would be ≥ 2 × OPC; rejection of the null hypothesis would demonstrate that these rates were below acceptable rates. The analysis was required to include at least 150 patients followed to 1 year and 400 valve-years. Kaplan-Meier survival analysis was also performed. RESULTS: Total number of valve-years was 459.5 (n = 686). Linearized rates were <2 × OPC for death and valve-related thromboembolism, valve thrombosis, all and major PVL, and endocarditis, but ≥2 × OPC for all and major haemorrhage. Survival at 1 year (n = 270) was 96.4%. Patients showed good functional recovery, and haemodynamic performance was within expected range. CONCLUSIONS: This analysis demonstrated a good safety profile and clinical effectiveness of the Avalus valve except for bleeding rates. The linearized rates of all and major haemorrhage may be related to long-term anticoagulation for non-valvular indications and the length of follow-up of this cohort. TRIAL REGISTRATION: NCT02088554 (www.clinicaltrials.gov).


Assuntos
Insuficiência da Valva Aórtica/cirurgia , Estenose da Valva Aórtica/cirurgia , Valva Aórtica/cirurgia , Bioprótese , Próteses Valvulares Cardíacas , Hemodinâmica/fisiologia , Stents , Doença Aguda , Idoso , Animais , Valva Aórtica/diagnóstico por imagem , Insuficiência da Valva Aórtica/diagnóstico , Insuficiência da Valva Aórtica/fisiopatologia , Estenose da Valva Aórtica/diagnóstico , Estenose da Valva Aórtica/fisiopatologia , Bovinos , Doença Crônica , Feminino , Seguimentos , Humanos , Masculino , Estudos Prospectivos , Desenho de Prótese , Fatores de Tempo , Resultado do Tratamento
6.
Pacing Clin Electrophysiol ; 33(8): 1020-30, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20545869

RESUMO

OBJECTIVES: The CAPTURE study evaluated the accuracy of automated atrial and right ventricular (RV) threshold algorithms. BACKGROUND: Modern pacemakers include many added features designed to improve the ease of patient follow-up, as well as algorithms to reduce pacing outputs and/or reduce the atrial or ventricular pacing percentages, thus improving longevity. METHODS: Automated atrial and RV threshold measurements were assessed versus manual measurements at 6 months. The projected longevity was assessed and compared between subjects with the threshold-tracking feature On versus Off. In addition, the projected longevity effect of device features to reduce atrial pacing and reduce ventricular pacing, and device characteristics such as battery size and high impedance leads (> or =1,000 ohms), was investigated. RESULTS: Atrial and RV manual versus automatic measurements were equivalent in 683 of 691 subjects (98.8%) and 736 of 746 subjects (98.7%), respectively. Thresholds were stable with 99.6% of atrial and 99.2% of RV consecutive measurements within +/-0.25V. Algorithms for threshold tracking, reducing ventricular pacing, and reducing atrial pacing were associated with 0.8, 0.9, and 0.2 years projected longevity improvements. High impedance leads were associated with a 0.8-year projected longevity improvement. Approximately 2 years of longevity improvement was projected for a 1-cc increase in device size. CONCLUSIONS: The atrial and RV algorithms were accurate and reliable in all leads tested. Threshold tracking, reduced ventricular pacing, and high impedance leads result in increased device longevity. Battery capacity was the strongest determinant of increased projected longevity.


Assuntos
Estimulação Cardíaca Artificial , Fontes de Energia Elétrica , Marca-Passo Artificial , Idoso , Algoritmos , Falha de Equipamento , Feminino , Frequência Cardíaca , Humanos , Masculino
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