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PURPOSE: The purpose of this study was to evaluate safety and cardiovascular outcomes as well as overall survival of cancer patients with concomitant heart failure (HF) treated with midodrine for hypotension. METHODS: Adult patients diagnosed with cancer and HF who were treated with midodrine at a tertiary cancer center from 03/2013 to 08/2021 were identified. Demographic and clinical parameters were collected retrospectively. RESULTS: A total of 85 patients were included with a median age of 68 years (IQR: 60, 74; 33% female and 85% White). Of those, 31% had HFpEF (EF ≥ 50%), 42% HF with mildly reduced EF (HFmrEF; EF 41-49%), and 27% HFrEF (EF ≤ 40%). The most common indication for midodrine use was orthostatic hypotension (49%). Midodrine was continued for at least one month in 57% of the patients. Supine hypertension was the only side effect reported in 6% of patients. No statistically significant changes in NYHA class, guideline-directed medical therapy, cardiac biomarkers (NT-proBNP or troponin T), echocardiographic findings or cardiovascular hospitalizations were observed between patients who continued treatment with midodrine compared to those who stopped using midodrine over a median follow-up of 38 months. In the multivariable cox regression analysis, continuation of midodrine, compared to discontinuation, and use of midodrine for orthostatic hypotension, as opposed to other causes of hypotension, were not associated with an increased risk of mortality (HR 0.41, 95% CI 0.24-0.69, p < .0001; HR 0.34, 95% CI 0.18-0.64, p < .001, respectively). In contrast, elevated creatinine (> 1.3 for males and > 1.1 for females) was associated with an increased risk of mortality (HR 1.83, 95% CI 1.07-3.14). LVEF was not significantly associated with lower or higher risk of mortality. CONCLUSIONS: In our study, midodrine use in patients with cancer and HF was not associated with significant adverse effects, worse cardiovascular outcomes, or increased risk of mortality. Larger, prospective studies are needed to confirm these findings.
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BACKGROUND: There is a paucity of data regarding the comparative efficacy and safety of Mitral valve transcatheter edge-to-edge repair (MTEER) using the PASCAL or MitraClip systems for patients with mitral regurgitation (MR). METHODS: An electronic search was conducted for MEDLINE, COCHRANE, and EMBASE, through February 2023, for studies comparing the clinical outcomes of MTEER using PASCAL versus MitraClip systems among patients with severe MR. The primary study outcome was residual MR ≤ 2 at discharge. Data were pooled using a random-effects model. RESULTS: The final analysis included six studies with a total of 1581 patients, with a weighted follow-up period of 3.5 months. Two studies only included patients with degenerative MR, while the remaining studies included both degenerative and functional MR. There was no significant difference in procedure duration between MTEER with the PASCAL or MitraClip systems. There was no difference in residual MR ≤ 2 at discharge (94.7% vs. 91.9%; odds ratio [OR]: 1.44; 95% confidence interval [CI]: 0.92-2.27) or residual MR ≤ 2 at the mid-term follow-up (94.6% vs. 91.0%, p = 0.05) among the PASCAL versus MitraClip systems. There was no difference between both groups in residual MR ≤ 1 at discharge (73.1% vs. 63.8%, p = 0.12), while there was greater incidence of residual MR ≤ 1 at midterm follow-up with the PASCAL system (71.3% vs. 56.2%, p < 0.001). There was no difference between the PASCAL and MitraClip MTEER systems in technical success (97.0% vs. 97.9%, p = 0.15), procedural success (89.1% vs. 87.1%, p = 0.78), single leaflet detachment (1.8% vs. 1.4%, p = 0.55), or all-cause mortality (3.6% vs. 4.6%, p = 0.71). CONCLUSION: In this meta-analysis, we demonstrated comparable efficacy and safety between the PASCAL and MitraClip MTEER systems at short- and mid-term assessments. Randomized trials are warranted to evaluate the comparative long-term outcomes between both MTEER systems.
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Implante de Prótese de Valva Cardíaca , Insuficiência da Valva Mitral , Humanos , Insuficiência da Valva Mitral/diagnóstico por imagem , Insuficiência da Valva Mitral/cirurgia , Valva Mitral/diagnóstico por imagem , Valva Mitral/cirurgia , Resultado do Tratamento , Cateterismo Cardíaco/efeitos adversosRESUMO
AIM: To determine whether photobiomodulation (PBM) therapy could increase the depth of analgesia during endodontic therapy of teeth affected with symptomatic irreversible pulpitis. MATERIALS AND METHODS: Forty-nine patients with symptomatic irreversible pulpitis were randomized into two groups. In the laser group, before administering anesthesia, the lower molars' crowns were continuously treated with a diode laser (980 nm) for 20 s with a low-level laser tip in the buccal aspect close to the gingival margin. While the teeth of the second group who was blinded to the type of treatment received placebo treatment wherein the laser device was switched off. The visual analogue scale (VAS) was used to assess pain in both groups before the endodontic procedure, during dentin cutting, and at dropping pulp, wherein, the success was defined as no or mild pain. The Chi-square and independent sample t-tests were used to assess the data. RESULTS: During dentin cutting and pulp dropping, the group receiving the laser therapy presented with less mean pain score than the placebo group which was statistically significant. Additionally, it was observed that the need for supplementary injection was less frequent in the laser-treated group than in the placebo group (p = 0.01). CONCLUSION: The irradiation by diode laser (980 nm) prior to administration of local anesthesia appears to be useful in minimizing discomfort and additional injection during root canal therapy (RCT). CLINICAL SIGNIFICANCE: Pain management is essential for providing the best possible treatment to patients before, during, and after endodontic therapy. Adequate pain control during treatment also aids in reducing postoperative discomfort. This implies the need for additional methods to reduce discomfort during endodontic treatment; hence, adjuncts are crucial to achieving this goal. Photobiomodulation may be used as an adjuvant to reduce discomfort and supplementary injections during RCT.
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Pulpite , Humanos , Pulpite/terapia , Anestesia Local , Assistência Odontológica , Polpa Dentária , DorRESUMO
OBJECTIVES: The aim of the study was to evaluate the outcomes of retrograde versus antegrade approach in chronic total occlusion (CTO) percutaneous coronary intervention (PCI). BACKGROUND: The retrograde approach has increased the success rate of CTO PCI but has been associated with a higher risk for complications. METHODS: We conducted a meta-analysis of studies published between 2000 and August 2019 comparing the in-hospital and long-term outcomes with retrograde versus antegrade CTO PCI. RESULTS: Twelve observational studies (10,240 patients) met our inclusion criteria (retrograde approach 2,789 patients, antegrade approach 7,451 patients). Lesions treated with the retrograde approach had higher J-CTO score (2.8 vs. 1.9, p < .001). Retrograde CTO PCI was associated with a lower success rate (80.9% vs. 87.4%, p < .001). Both approaches had similar in-hospital mortality, urgent revascularization, and cerebrovascular events. Retrograde CTO PCI was associated with higher risk of in-hospital myocardial infarction (MI; odds ratio [OR] 2.37, 95% confidence intervals [CI] 1.7, 3.32, p < .001), urgent pericardiocentesis (OR 2.53, 95% CI 1.41-4.51, p = .002), and contrast-induced nephropathy (OR 2.12, 95% CI 1.47-3.08; p < .001). During a mean follow-up of 48 ± 31 months retrograde crossing had similar mortality (OR 1.79, 95% CI 0.84-3.81, p = .13), but a higher incidence of MI (OR 2.07, 95% CI 1.1-3.88, p = .02), target vessel revascularization (OR 1.92, 95% CI 1.49-2.46, p < .001), and target lesion revascularization (OR 2.08, 95% CI 1.33-3.28, p = .001). CONCLUSIONS: Compared with antegrade CTO PCI, retrograde CTO PCI is performed in more complex lesions and is associated with a higher risk for acute and long-term adverse events.
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Oclusão Coronária/terapia , Intervenção Coronária Percutânea , Doença Crônica , Oclusão Coronária/diagnóstico por imagem , Oclusão Coronária/mortalidade , Mortalidade Hospitalar , Humanos , Infarto do Miocárdio/mortalidade , Infarto do Miocárdio/terapia , Estudos Observacionais como Assunto , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/mortalidade , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do TratamentoRESUMO
BACKGROUND: Emotional stress is associated with increased risk of cardiovascular disease. We imaged the amygdala, a brain region involved in stress, to determine whether its resting metabolic activity predicts risk of subsequent cardiovascular events. METHODS: Individuals aged 30 years or older without known cardiovascular disease or active cancer disorders, who underwent 18F-fluorodexoyglucose PET/CT at Massachusetts General Hospital (Boston, MA, USA) between Jan 1, 2005, and Dec 31, 2008, were studied longitudinally. Amygdalar activity, bone-marrow activity, and arterial inflammation were assessed with validated methods. In a separate cross-sectional study we analysed the relation between perceived stress, amygdalar activity, arterial inflammation, and C-reactive protein. Image analyses and cardiovascular disease event adjudication were done by mutually blinded researchers. Relations between amygdalar activity and cardiovascular disease events were assessed with Cox models, log-rank tests, and mediation (path) analyses. FINDINGS: 293 patients (median age 55 years [IQR 45·0-65·5]) were included in the longitudinal study, 22 of whom had a cardiovascular disease event during median follow-up of 3·7 years (IQR 2·7-4·8). Amygdalar activity was associated with increased bone-marrow activity (r=0·47; p<0·0001), arterial inflammation (r=0·49; p<0·0001), and risk of cardiovascular disease events (standardised hazard ratio 1·59, 95% CI 1·27-1·98; p<0·0001), a finding that remained significant after multivariate adjustments. The association between amygdalar activity and cardiovascular disease events seemed to be mediated by increased bone-marrow activity and arterial inflammation in series. In the separate cross-sectional study of patients who underwent psychometric analysis (n=13), amygdalar activity was significantly associated with arterial inflammation (r=0·70; p=0·0083). Perceived stress was associated with amygdalar activity (r=0·56; p=0·0485), arterial inflammation (r=0·59; p=0·0345), and C-reactive protein (r=0·83; p=0·0210). INTERPRETATION: In this first study to link regional brain activity to subsequent cardiovascular disease, amygdalar activity independently and robustly predicted cardiovascular disease events. Amygdalar activity is involved partly via a path that includes increased bone-marrow activity and arterial inflammation. These findings provide novel insights into the mechanism through which emotional stressors can lead to cardiovascular disease in human beings. FUNDING: None.
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Tonsila do Cerebelo/diagnóstico por imagem , Tonsila do Cerebelo/metabolismo , Doenças Cardiovasculares/metabolismo , Doenças Cardiovasculares/psicologia , Estresse Psicológico/metabolismo , Idoso , Artérias/fisiopatologia , Aterosclerose/fisiopatologia , Medula Óssea/metabolismo , Doenças Cardiovasculares/diagnóstico por imagem , Estudos Transversais , Fluordesoxiglucose F18 , Hematopoese/fisiologia , Humanos , Inflamação/fisiopatologia , Estudos Longitudinais , Pessoa de Meia-Idade , Percepção , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Compostos Radiofarmacêuticos , Fatores de RiscoAssuntos
Fragilidade , Abdome/cirurgia , Idoso , Fragilidade/diagnóstico , Avaliação Geriátrica , HumanosRESUMO
3-Bromopyruvate (3BP) is a new, promising anticancer alkylating agent with several notable functions. In addition to inhibiting key glycolysis enzymes including hexokinase II and lactate dehydrogenase (LDH), 3BP also selectively inhibits mitochondrial oxidative phosphorylation, angiogenesis, and energy production in cancer cells. Moreover, 3BP induces hydrogen peroxide generation in cancer cells (oxidative stress effect) and competes with the LDH substrates pyruvate and lactate. There is only one published human clinical study showing that 3BP was effective in treating fibrolamellar hepatocellular carcinoma. LDH is a good measure for tumor evaluation and predicts the outcome of treatment better than the presence of a residual tumor mass. According to the Warburg effect, LDH is responsible for lactate synthesis, which facilitates cancer cell survival, progression, aggressiveness, metastasis, and angiogenesis. Lactate produced through LDH activity fuels aerobic cell populations inside tumors via metabolic symbiosis. In melanoma, the most deadly skin cancer, 3BP induced necrotic cell death in sensitive cells, whereas high glutathione (GSH) content made other melanoma cells resistant to 3BP. Concurrent use of a GSH depletor with 3BP killed resistant melanoma cells. Survival of melanoma patients was inversely associated with high serum LDH levels, which was reported to be highly predictive of melanoma treatment in randomized clinical trials. Here, we report a 28-year-old man presented with stage IV metastatic melanoma affecting the back, left pleura, and lung. The disease caused total destruction of the left lung and a high serum LDH level (4,283 U/L). After ethics committee approval and written patient consent, the patient received 3BP intravenous infusions (1-2.2 mg/kg), but the anticancer effect was minimal as indicated by a high serum LDH level. This may have been due to high tumor GSH content. On combining oral paracetamol, which depletes tumor GSH, with 3BP treatment, serum LDH level dropped maximally. Although a slow intravenous infusion of 3BP appeared to have minimal cytotoxicity, its anticancer efficacy via this delivery method was low. This was possibly due to high tumor GSH content, which was increased after concurrent use of the GSH depletor paracetamol. If the anticancer effectiveness of 3BP is less than expected, the combination with paracetamol may be needed to sensitize cancer cells to 3BP-induced effects.
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Acetaminofen/uso terapêutico , Progressão da Doença , Neoplasias Pulmonares/secundário , Melanoma/tratamento farmacológico , Neoplasias Pleurais/secundário , Prognóstico , Piruvatos/uso terapêutico , Resultado do Tratamento , Adulto , Carcinoma Hepatocelular , Quimioterapia Combinada , Inibidores Enzimáticos , Glutationa , Glicólise , Hexoquinase , Humanos , L-Lactato Desidrogenase , Ácido Láctico , Masculino , Necrose , Neovascularização Patológica , Piruvatos/efeitos adversosRESUMO
INTRODUCTION: We conducted the first comprehensive evaluation of the therapeutic value and safety profile of transcatheter mitral edge-to-edge repair (TEER) and transcatheter mitral valve replacement (TMVR) in individuals concurrently afflicted with cancer. METHODS: Utilizing the National Inpatient Sample (NIS) dataset, we analyzed all adult hospitalizations between 2016 and 2020 (n = 148,755,036). The inclusion criteria for this retrospectively analyzed prospective cohort study were all adult hospitalizations (age 18 years and older). Regression and machine learning analyses in addition to model optimization were conducted using ML-PSr (Machine Learning-augmented Propensity Score adjusted multivariable regression) and BAyesian Machine learning-augmented Propensity Score (BAM-PS) multivariable regression. RESULTS: Of all adult hospitalizations, there were 5790 (0.004%) TMVRs and 1705 (0.001%) TEERs. Of the total TMVRs, 160 (2.76%) were done in active cancer. Of the total TEERs, 30 (1.76%) were done in active cancer. After the comparable rates of TEER/TMVR in active cancer in 2016, the prevalence of TEER/TMVR was significantly less in active cancer from 2017 to 2020 (2.61% versus 7.28% p < 0.001). From 2017 to 2020, active cancer significantly decreased the odds of receiving TEER or TMVR (OR 0.28, 95%CI 0.13-0.68, p = 0.008). In patients with active cancer who underwent TMVR/TEER, there were no significant differences in socio-economic disparities, mortality or total hospitalization costs. CONCLUSION: The presence of malignancy does not contribute to increased mortality, length of stay or procedural costs in TMVR or TEER. Whereas the prevalence of TMVR has increased in patients with active cancer, the utilization of TEER in the context of active cancer is declining despite a growing patient population.
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Inteligência Artificial , Implante de Prótese de Valva Cardíaca , Insuficiência da Valva Mitral , Neoplasias , Pontuação de Propensão , Humanos , Masculino , Feminino , Neoplasias/cirurgia , Neoplasias/economia , Neoplasias/mortalidade , Neoplasias/epidemiologia , Idoso , Implante de Prótese de Valva Cardíaca/economia , Implante de Prótese de Valva Cardíaca/métodos , Implante de Prótese de Valva Cardíaca/tendências , Pessoa de Meia-Idade , Inteligência Artificial/economia , Inteligência Artificial/tendências , Prevalência , Insuficiência da Valva Mitral/cirurgia , Insuficiência da Valva Mitral/economia , Estados Unidos/epidemiologia , Estudos Retrospectivos , Cateterismo Cardíaco/economia , Estudos Prospectivos , Adulto , Idoso de 80 Anos ou mais , Disparidades em Assistência à Saúde/economia , Disparidades em Assistência à Saúde/tendências , Estudos de CoortesRESUMO
Cangrelor, a potent intravenous P2Y12 platelet inhibitor, has demonstrated effectiveness in reducing ischemic events without a corresponding increase in severe bleeding during percutaneous coronary intervention, as evidenced by the CHAMPION-PHOENIX trial. Its off-label role as a bridging antiplatelet agent for patients facing high thrombotic risks who must temporarily stop oral P2Y12 inhibitor therapy further underscores its clinical utility. This is the first case series to shed light on the application of cangrelor in cancer patients needing to pause dual antiplatelet therapy for a range of medical interventions, marking it as a pioneering effort in this domain. The inclusion of patients with a variety of cancer types and cardiovascular conditions in this series underlines the adaptability and critical role of cangrelor in managing the dual challenges of bleeding risk and the need for uninterrupted antiplatelet protection. By offering a bridge for high-risk cancer patients who have recently undergone percutaneous coronary intervention and need to halt oral P2Y12 inhibitors temporarily, cangrelor presents a practical solution. Early findings indicate it can be discontinued safely 2-4 h before medical procedures, allowing for the effective reintroduction of oral P2Y12 inhibitors without adverse effects. This evidence calls for expanded research to validate and extend these preliminary observations, emphasizing the importance of further investigation into cangrelor's applications in complex patient care scenarios.
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INTRODUCTION: The impact of peripheral cytokine levels on the prognosis and treatment of immune checkpoint inhibitor (ICI) myocarditis has not been well studied. OBJECTIVES: This study aimed to identify cytokines that can prognosticate and direct the treatment of ICI myocarditis. METHODS: This was a single-center, retrospective cohort study of patients with ICI myocarditis who had available peripheral cytokine levels between January 2011 and May 2022. Major adverse cardiovascular events (MACEs) were defined as a composite of heart failure with/without cardiogenic shock, arterial thrombosis, life-threatening arrhythmias, pulmonary embolism, and sudden cardiac death. RESULTS: In total, 65 patients with ICI myocarditis had cytokine data available. Patients were mostly males (70%), with a mean age of 67.8 ± 12.7 years. Interleukin (IL)-6 and tumor necrosis factor-α (TNF-α) were the most common cytokines to be elevated with 48/65 (74%) of patients having a peak IL-6 above normal limits (>5 pg/mL) and 44/65 (68%) of patients with peak TNF-α above normal limits (>22 pg/mL). Patients with elevated peak IL-6 had similar 90-day mortality and MACE outcomes compared to those without (10.4% vs. 11.8%, p = 0.878 and 8.8% vs. 17.7%, p = 0.366, respectively). Similarly, those with elevated peak TNF-α had similar 90-day mortality and MACEs compared to those without (29.6% vs. 14.3%, p = 0.182 and 13.6% vs. 4.8%, p = 0.413, respectively). Kaplan-Meier survival analysis also showed that there was not a significant difference between MACE-free survival when comparing elevated and normal IL-6 and TNF-α levels (p = 0.182 and p = 0.118, respectively). MACEs and overall survival outcomes were similar between those who received infliximab and those who did not among all patients and those with elevated TNF-α (p-value 0.70 and 0.83, respectively). CONCLUSION: Peripheral blood levels of IL-6 and TNF-α are the most commonly elevated cytokines in patients with ICI myocarditis. However, their role in the prognostication and guidance of immunomodulatory treatment is currently limited.
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BACKGROUND: Previous studies have documented a negative impact of the COVID-19 pandemic on emergent percutaneous treatment of patients with ST-segment elevation myocardial infarction (STEMI), but few have examined recovery of healthcare systems in restoring prepandemic STEMI care. METHODS: Retrospective analysis was performed of data from 789 patients with STEMI from a large tertiary medical center treated with percutaneous coronary intervention between January 1, 2019, and December 31, 2021. RESULTS: For patients with STEMI presenting to the emergency department, median time from door to balloon was 37 minutes in 2019, 53 minutes in 2020, and 48 minutes in 2021 (P < .001), whereas median time from first medical contact to device changed from 70 to 82 to 75 minutes, respectively (P = .002). Treatment time changes in 2020 and 2021 correlated with median emergency department evaluation time (30 to 41 to 22 minutes, respectively; P = .001) but not median catheterization laboratory revascularization time. For transfer patients, median time from first medical contact to device changed from 110 to 133 to 118 minutes, respectively (P = .005). In 2020 and 2021, patients with STEMI had greater late presentation (P = .028) and late mechanical complications (P = .021), with nonsignificant increases in yearly in-hospital mortality (3.6% to 5.2% to 6.4%; P = .352). CONCLUSION: COVID-19 was associated with worsening STEMI treatment times and outcomes in 2020. Despite improving treatment times in 2021, in-hospital mortality had not decreased in the setting of a persistent increase in late patient presentation and associated STEMI complications.
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COVID-19 , Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST , Humanos , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico , Infarto do Miocárdio com Supradesnível do Segmento ST/terapia , Infarto do Miocárdio com Supradesnível do Segmento ST/etiologia , Estudos Retrospectivos , Pandemias , Fatores de Tempo , Intervenção Coronária Percutânea/efeitos adversos , Tempo para o TratamentoRESUMO
Purpose of review: The treatment of coronary artery disease (CAD) in cancer patients is an evolving landscape. Recent data emphasizes the importance of aggressive management of cardiovascular risk factors and diseases in improving cardiovascular health in this unique group of patients regardless of cancer type or stage. Recent findings: Novel cancer therapeutics such as immune therapies and proteasome inhibitors have been associated with CAD. Recent stent technologies may safely allow for shorter duration (< 6 months) of dual antiplatelet therapy post-percutaneous coronary interventions. Intracoronary imaging may be useful in the decision making process in terms of stent positioning and healing. Summary: Large registry studies have partially filled a gap left by the lack of randomized controlled trials in the treatment of CAD in cancer patients. Cardio-oncology is gaining traction as a major sub-specialty in the cardiology field given the release of the first European Society of Cardiology - Cardio-oncology guidelines in 2022.
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Commerce has had positive impacts on the whole agri-food value chain at different stages, it was developed rapidly in rural China in the past few years. E-commerce participation can promote the use intensity of organic fertilizers (OF) and this could achieve many benefits for different stakeholders including ensuring food safety, positive environmental impacts and promoting the adoption of green production technologies. Therefore, this study has used primary data collected from 733 fruit farmers in rural China to explore the impact of e-commerce participation on fruit farmers' use intensity of (OF). Unlike previous studies investigating the dichotomous decision of (OF) adoption, this study captures the use intensity of (OF) from both input quantity and cost aspects. We employed an endogenous switching regression (ESR) model to address selectivity bias caused by observed and unobserved factors. The results show that e-commerce participation significantly increases the use intensity of (OF) in input quantity and cost by 19.48% and 29.50%, respectively. Heterogeneous analysis further reveals that compared to fruit farmers with a low e-commerce participation level, fruit farmers with a high e-commerce participation level have higher (OF) use intensity. The findings also show that risk preference, human capital, cultivated area, cooperative membership and government restraint mechanisms positively and significantly affect the probability of fruit farmers' participation in e-commerce and fruit farmers' use intensity of (OF). The results emphasize that e-commerce promotion is an efficient way to encourage farmers to adopt (OF), which help improve product quality and promote sustainable agricultural development.
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Fertilizantes , Frutas , Agricultura , China , Comércio , Fazendeiros , HumanosRESUMO
Magnetorheological elastomers (MREs) are smart viscoelastic materials in which their physical properties can be altered when subjected to a varying magnetic field strength. MREs consist of an elastomeric matrix mixed with magnetic particles, typically carbonyl iron particles (CIPs). The magnetic field-responsive property of MREs have led to their wide exposure in research. The potential development and commercialization of MRE-based devices requires extensive investigation to identify the essential factors that can affect their properties. For this reason, this research aims to investigate the impact of CIPs' type, concentration and coating on the rheological and mechanical properties of MREs. Isotropic MREs are fabricated with four different CIP compositions differing between hard or soft, and coated or uncoated samples. Each MRE composition have three different concentrations, which is 5%, 10%, and 20% by volume. The dynamic properties of the fabricated samples are tested by compression oscillations on a dynamic mechanical analyzer (DMA). Frequency and strain dependent measurements are performed to obtain the storage and loss modulus under different excitation frequencies and strain amplitudes. The emphasis is on the magnetorheological (MR) effect and the Payne effect which are an intrinsic characteristics of MREs. The effect of the CIPs' type, coating, and concentration on the MR and Payne effect of MREs are elucidated. Overall, it is observed that, the storage and loss modulus exhibit a strong dependence on both the frequency excitations and the strain amplitudes. Samples with hard and coated CIPs tend to have a higher MR effect than other samples. A decrease in the storage modulus and non-monotonous behavior of the loss modulus with increasing strain amplitude are observed, indicating the Payne effect. The results of this study can aid in the characterization of MREs and the proper selection of CIPs grades based on the application.
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Magnetorheological elastomers (MREs) are a class of emerging smart materials in which their mechanical and rheological properties can be immediately and reversibly altered upon the application of a magnetic field. The change in the MRE properties under the magnetic field is widely known as the magnetorheological (MR) effect. Despite their inherent viscoelastic property-change characteristics, there are disadvantages incorporated with MREs, such as slow response time and the suspension of the magnetic particles in the elastomer matrix, which depress their MR effect. This study investigates the feasibility of a hybrid magnetorheological elastomer-fluid (MRE-F) for longitudinal vibration isolation. The hybrid MRE-F is fabricated by encapsulating MR fluid inside the elastomer matrix. The inclusion of the MR fluid can enhance the MR effect of the elastomer by providing a better response to the magnetic field and, hence, can improve the vibration isolation capabilities. For this purpose, an MRE-based coupling is developed, and isolation performance is investigated in terms of the linear transmissibility factor. The performance of the hybrid MRE-F was compared against two different MRE samples. The results show that further enhancement of MR-effect in MREs is possible by including MR fluid inside the elastomer. The hybrid MRE-F exhibited better stiffness change with the current increase and recorded the highest value of 55.911 N/mm. The transmissivity curves revealed that the MRE-F contributed to a broader shift in the natural frequency with a 7.2 Hz overall shift at 8.9 mT. The damping characteristics are higher in MRE-F, recording the highest percentage increase in damping with 33.04%. Overall, the results reveal the promising potential of hybrid MRE-F in developing MRE-based coupling for longitudinal vibration isolation.
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BACKGROUND: Diabetic foot ulcer (DFU) is one of the most serious diabetic complications. DFU is an open wound that usually occurs in the foot sole due to poor blood glucose control, peripheral neuropathy, and poor circulation. The human amniotic allograft membrane is a biological wound dressing derived from the amniotic membrane. It contains amino acids, nutrients, cytokines, and growth factors that make the growth process easier. OBJECTIVE: To compare dehydrated human amnion and chorion allograft (DHACA) plus the standard of wound care (SOC) with the SOC alone. METHODS: We searched for randomized clinical trials (RCTs) on PubMed, Scopus, Cochrane, and Web of Science till April 2021 using relevant keywords. All search results were screened for eligibility. We extracted the data from the included trials and pooled them as mean difference (MD) or risk ratio (RR) with the 95% confidence interval (CI) using Review Manager software (ver. 5.4). RESULTS: The pooled effect estimate from 11 RCTs showed that DHACA was superior to SOC regarding the complete wound healing in both 6th and 12th week (RR = 3.78; 95% CI: [2.51, 5.70]; P < 0.00001) and (RR = 2.00; 95% CI: [1.67, 2.39], P < 0.00001 respectively). Also, the analysis favored the DHACA regarding the mean time to heal in the 12th-week (MD = -12.07, 95%CI: [-19.23, -4.91], P = 0.001). The wound size reduction was better with DHACA (MD = 1.18, 95%CI: [-0,10, 2.26], P = 0.03). CONCLUSION: Using DHACA with SOC is safer and more effective than using SOC alone for DFU patients.
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Diabetes Mellitus , Pé Diabético , Âmnio/transplante , Pé Diabético/terapia , Humanos , Padrão de Cuidado , Resultado do Tratamento , CicatrizaçãoRESUMO
Introduction: This study examined the role of echocardiographic and cardiac histomorphology parameters in predicting mortality in patients with cardiac AL amyloidosis. Methods: Patients with endomyocardial biopsy-proven cardiac AL amyloidosis treated at MD Anderson Cancer Center between 6/2011 and 6/2020 were identified. Stored echocardiographic images and endomyocardial biopsy samples were processed for myocardial strain analysis and a detailed histomorphology characterization. Results: Of 43 patients; 44% were women and 63% white. Median age was 65 years; 51% underwent stem cell transplantation (SCT). Thirty patients (70%) died during follow up (median follow up: 4.1 years). Lower LA strain (<13.5%) and absence of SCT as a time-varying covariate were significantly associated with increased risk of death in the multivariate cox regression analysis. Higher LV mass and lower RV tricuspid annular plane systolic excursion were associated with increased odds of having ≥5% interstitial amyloid deposition on biopsy in the multivariate logistic regression analysis. Conclusion: Lower LA strain independently predicted mortality in our cohort, and its performance in the routine assessment of AL amyloidosis may be beneficial. Furthermore, SCT for cardiac AL amyloidosis was associated with improved OS. These findings need to be confirmed by larger studies in the era of contemporary systemic therapies.
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BACKGROUND: Although prior national reports have identified trends in the underutilization of transcatheter aortic valve replacement (TAVR) in Afro-American and Latino populations, racial and ethnic healthcare disparities in TAVR use in the State of Connecticut have not been previously reported. METHODS: We conducted a retrospective analysis of 1461 patients undergoing TAVR at our institute between from 2012 to 2020. Baseline demographics, procedural characteristics, clinical outcomes, median incomes and insurance coverage were compared between 1417 Caucasian and 44 minority patients, including 23 patients designated as Afro-American and 10 designated as Latino. Demographics of TAVR utilization at our institution were further compared to 6 additional Connecticut TAVR centers using Connecticut Hospital Association (CHA) ChimeData detailing hospital discharges for DRG 266 and 267. RESULTS: In comparison to Caucasian patients, minority cohorts were younger (75.7 ± 9.0 vs 81.5 ± 5.1 years, p < 0.001) and had more co-morbidities including diabetes (64% vs 34%, p < 001), coronary artery disease (95% vs 78%, p = 0.039), end stage renal disease requiring dialysis (9% vs 3%, p = 0.009) and atrial fibrillation (77% vs 62%, p = 0.041). The two groups did not differ with respect to other risk factors or co-morbidities, baseline echocardiographic or CTA findings, STS risk score, or procedural technique. Minority patients had a longer length of hospital stay (9.5 ± 9.0 vs 6.4 ± 6.9 days, p = 0.003), but did not differ with respect to procedural complications. Socioeconomic differences between the two groups included lower median incomes and higher rates of Medicaid or no insurance coverage for minority versus Caucasian patients. CHA ChimeData revealed a similar underutilization of TAVR in minority subgroups in the remaining 6 Connecticut TAVR centers. CONCLUSIONS: Despite statewide demographics describing 10.7% and 15.7% of the total population as Afro-American and Latino, respectively, only 3.0% of the total TAVR procedures performed at a large Connecticut health care facility were performed in minority subgroups. Despite having a higher burden of co-morbidities, minority patients had similar outcomes compared to Caucasian patients. Similar racial and ethnic disparities in TAVR utilization were confirmed statewide using CHA ChimeData.
Assuntos
Estenose da Valva Aórtica , Substituição da Valva Aórtica Transcateter , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/cirurgia , Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/cirurgia , Connecticut/epidemiologia , Mortalidade Hospitalar , Humanos , Estudos Retrospectivos , Fatores de Risco , Substituição da Valva Aórtica Transcateter/métodos , Resultado do Tratamento , Estados Unidos/epidemiologiaRESUMO
Climate change is severely damaging the agricultural system of many food producing regions worldwide. Small/subsistent livestock herders are the most vulnerable and less resilient group towards climatic disasters within South Asian region including Pakistan. The adoption of climate-smart practices would be beneficial for small livestock herders because of its potential to ensure food security, improve income, and sustain development simultaneously. The purpose of this paper is to investigate factors influencing small livestock herders' adaptation decisions towards changing climate by conducting field-based research. We intend to understand how institutional factors, risk perceptions, adaptations, and personal constraints affect the adaptation decisions related to climate change mitigation and choice of adaptation strategies. For this purpose, a primary data set of 405 small livestock herders from Punjab, Pakistan was used. The regression results of empirical models reveal the probability of adopting specific climate change strategies. The study results showed that zero adaptation (non-adoption) to climate change is higher when there is low literacy rate, less experience, nuclear family system, lack of institutional services, and low level of risk perception about climate change. The marginal outcome showed that the livestock herders with positive risk perception and access to the institutional services do participate more frequently in a higher number of adaptations options for economic and ecological benefits. Therefore, it is suggested that government and other development actors should strengthen institutions for trust building among local community groups and to reduce individuals' risks. Moreover, effective insurance schemes could facilitate small livestock herders to keep less but more productive livestock. The study recommends building viable and potential weather index insurance schemes which will result meaningful marginal scale benefits for smallholders. Finally, the results of major constraints suggest that it is necessary to provide awareness of climatic vulnerabilities, timely information delivery, and adequate financial facilities to offset resource constraints of livestock herders in order to adopt sustainable strategies at their farms.