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BACKGROUND: There is a need for scalable evidence-based psychological interventions for young adolescents experiencing high levels of psychological distress in humanitarian settings and low- and middle-income countries. Poor mental health during adolescence presents a serious public health concern as it is a known predictor of persistent mental disorders in adulthood. This study evaluates the effectiveness of a new group-based intervention developed by the World Health Organization (Early Adolescent Skills for Emotions; EASE), implemented by non-specialists, to reduce young adolescents' psychological distress among mostly Syrian refugees in Lebanon. METHODS: We conducted a two-arm, single-blind, individually randomized group treatment trial. Adolescents aged 10 to 14 years who screened positive for psychological distress using the Pediatric Symptom Checklist (PSC) were randomly allocated to EASE or enhanced treatment as usual (ETAU) (1:1.6). ETAU consisted of a single scripted psycho-education home-visit session with the adolescent and their caregivers. EASE consists of seven group sessions with adolescents and three sessions with caregivers. The primary outcome was adolescent-reported psychological distress as measured with the PSC (internalizing, externalizing, and attentional symptoms). Secondary outcomes included depression, posttraumatic stress, well-being, functioning, and caregivers' parenting and distress. All outcomes were assessed at baseline, endline, and 3 months (primary time point) and 12 months follow-up. RESULTS: Due to the COVID-19 pandemic and other adversities in Lebanon at the time of this research, the study was prematurely terminated, resulting in an under-powered trial sample (n = 198 enrolled compared to n = 445 targeted). We screened 604 children for eligibility. The 198 enrolled adolescents were assigned to EASE (n = 80) and ETAU (n = 118), with retention rates between 76.1 and 88.4% across all timepoints. Intent-to-treat analyses demonstrated no between-group differences on any of the outcome measures between the EASE and ETAU. We did observe a significant improvement on the primary outcome equally in the EASE and ETAU groups (-0.90, 95% CI: -3.6, 1.8; p = .52), - a trend that was sustained at three months follow-up. Sub-group analyses, for those with higher depression symptoms at baseline, showed ETAU outperformed EASE on reducing depression symptoms (difference in mean change = 2.7, 95% CI: 0.1, 5.3; p = .04; d = 0.59) and internalizing problems (difference in mean change 1.0, 95% CI: 0.08, 1.9; p = .03; d = 0.56) . CONCLUSION: No conclusions can be drawn about the comparative effectiveness of the intervention given that the sample was underpowered as a result of early termination. Both EASE and single session psycho-education home visits resulted in meaningful improvements in reducing psychological distress. We did not identify any indications in the data suggesting that EASE was more effective than a single session family intervention in the context of the COVID-19 pandemic and other crises in Lebanon. Fully powered research is needed to evaluate the effectiveness of EASE.
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COVID-19 , Angústia Psicológica , Humanos , Adolescente , Criança , Líbano/epidemiologia , Método Simples-Cego , Pandemias , COVID-19/epidemiologiaRESUMO
BACKGROUND: The existing algorithm for defining exercise-induced diastolic dysfunction incorporates resting e' velocity as a surrogate of myocardial relaxation. The additive prognostic value of incorporating post-exercise e' velocity in definition of exercise-induced diastolic dysfunction is poorly studied. AIM: To define the additive prognostic value of post-exercise e' septal velocity in the assessment of exercise-induced diastolic dysfunction compared to the traditional approach. METHODS: This retrospective study included 1409 patients undergoing exercise treadmill echocardiography with available full set of diastolic variables. Doppler measures of diastolic function included resting septal e' velocity, post-exercise septal e' velocity, post-exercise E/e' ratio, and post-exercise tricuspid regurgitant jet velocity. Approaches incorporating resting septal e' velocity and post-exercise septal e' velocity were compared in defining exercise-induced diastolic dysfunction, and for association with adverse cardiovascular outcomes. RESULTS: The mean age of study subjects was 56.3 ± 16.5 years and 791 (56%) patients were women. A total of 524 patients had disagreement between resting and post exercise septal e' velocities, and these values showed only weak agreement (kappa statistics: .28, P = .02). All categories of the traditional exercise-induced DD approach incorporating resting septal e' velocity witnessed reclassification when exercise septal e' velocity was used. When both approaches were compared, increased event rates were only evident when both approaches agreed on exercise-induced diastolic dysfunction (HR: 1.92, P < .001, 95% CI: 1.37-2.69). This association persisted after multivariable adjustment and propensity score matching for covariates. CONCLUSION: Incorporation of post-exercise e' velocity into the set of variables defining exercise-induced diastolic dysfunction can improve the prognostic utility of diastolic function assessment.
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Ecocardiografia , Disfunção Ventricular Esquerda , Humanos , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Masculino , Prognóstico , Estudos Retrospectivos , Teste de Esforço , Ultrassonografia Doppler , Diástole , Disfunção Ventricular Esquerda/diagnóstico por imagemRESUMO
PURPOSE: Data on the epidemiology of cardiovascular diseases (CVD) in patients with autosomal dominant polycystic kidney disease (ADPKD) are limited. In this study, we assess the prevalence of CVD in patients with ADPKD and evaluate associations between these two entities. METHODS: Using the National Inpatient Sample database, we identified 71,531 hospitalizations among adults aged ≥ 18 years with ADPKD, from 2006 to 2014 and collected relevant clinical data. RESULTS: The prevalence of CVD in the study population was 42.6%. The most common CVD were ischemic heart diseases (19.3%), arrhythmias (14.2%), and heart failure (13.1%). The prevalence of CVD increased with the severity of renal dysfunction (RD). We found an increase in hospitalizations of patients with ADPKD and CVD over the years (ptrend < 0.01), irrespective of the degree of RD. CVD was the greatest independent predictor of mortality in these patients (OR: 3.23; 95% CI 2.38-4.38 [p < 0.001]). In a propensity matched model of hospitalizations of patients with CKD with and without ADPKD, there was a significant increase in the prevalence of atrial fibrillation/flutter (AF), pulmonary hypertension (PHN), non-ischemic cardiomyopathy (NICM), and hemorrhagic stroke among patients with ADPKD when compared to patients with similar degree of RD without ADPKD. CONCLUSIONS: The prevalence of CVD is high among patients with ADPKD, and the most important risk factor associated with CVD is severity of RD. We found an increase in the trend of hospitalizations of patients with ADPKD associated with increased risk of AF, PHN, NICM, and hemorrhagic stroke. History of CVD is the strongest predictor of mortality among patients with ADPKD.
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Doenças Cardiovasculares , Acidente Vascular Cerebral Hemorrágico , Rim Policístico Autossômico Dominante , Adulto , Doenças Cardiovasculares/complicações , Doenças Cardiovasculares/epidemiologia , Humanos , Pacientes Internados , Rim Policístico Autossômico Dominante/complicações , Rim Policístico Autossômico Dominante/diagnóstico , Rim Policístico Autossômico Dominante/epidemiologia , Fatores de RiscoRESUMO
Beta-thalassemia intermedia (ß-TI) is associated with vascular dysfunction. We used digital thermal monitoring (DTM), a non-invasive tool that evaluates vascular function based on changes in fingertip temperature during and after cuff occlusion on ß-TI patients. Thirty-three patients (18 years and older) were recruited in this study and divided into 3 groups: thalassemia, anemic controls, and healthy controls. Exclusion criteria included factors that are known to be associated with vascular damage. Patients underwent DTM and results were extracted as vascular reactivity index (VRI), a measure of how well the circulatory system responds to stimuli that require adjustments of blood flow. One-way analysis of variance (ANOVA) was used to test the mean difference in VRI between the 3 groups. A multiple linear regression was also carried out with VRI as the outcome of interest and a function of covariates that were thought to be of clinical relevance to VRI. The frequency, mean VRI ± standard error (SE) for the thalassemic group were (N = 16), mean = 2.243 ± 0.111; for anemic controls (N = 9), mean = 2.374 ± 0.162; and for the controls (N = 8), mean = 2.338 ± 0.092. ANOVA test indicated a non-significant difference in mean VRI between the three groups (P value = 0.731). Multiple linear regression couldn't detect any significant association between VRI and any of the predictors including the groups. Our study did not show a significant difference in VRI between the 3 study groups. Prospective studies of larger sample size are warranted to establish DTM as a possible non-invasive tool used to evaluate vascular function in ß-TI patients.
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Termografia , Doenças Vasculares/diagnóstico por imagem , Doenças Vasculares/etiologia , Talassemia beta/complicações , Adulto , Circulação Sanguínea , Feminino , Dedos/irrigação sanguínea , Humanos , Masculino , Pessoa de Meia-Idade , Termografia/métodos , Doenças Vasculares/fisiopatologia , Adulto Jovem , Talassemia beta/fisiopatologiaRESUMO
Triaryl borate Lewis acids facilitate the direct two-electron reduction of the P(V) center of triphenylphosphine oxide (TPPO) to the P(III) center of triphenylphosphine at faradaic efficiencies of 37%. Insight from direct P(V) to P(III) reduction is provided from cyclic voltammetry. The electrochemical reduction of TPPO proceeds through an unusual ECrECi mechanism in which the breaking of the phosphoryl bond in a two-electron-reduced association complex with the triaryl borate is rate-determining. The rate and faradaic efficiency for TPPO reduction are tuned by judicious choice of substituents on triaryl borate, with tris(4-methoxyphenyl) borate demonstrating the highest for both. These results suggest that an attractive route toward the room-temperature reduction of phosphate for phosphorus reclamation is greatly facilitated by the stabilization of reduced phosphate intermediates through their association with Lewis acids.
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Owing to their high power density and superior cyclability relative to batteries, electrochemical double layer capacitors (EDLCs) have emerged as an important electrical energy storage technology that will play a critical role in the large-scale deployment of intermittent renewable energy sources, smart power grids, and electrical vehicles. Because the capacitance and charge-discharge rates of EDLCs scale with surface area and electrical conductivity, respectively, porous carbons such as activated carbon, carbon nanotubes and crosslinked or holey graphenes are used exclusively as the active electrode materials in EDLCs. One class of materials whose surface area far exceeds that of activated carbons, potentially allowing them to challenge the dominance of carbon electrodes in EDLCs, is metal-organic frameworks (MOFs). The high porosity of MOFs, however, is conventionally coupled to very poor electrical conductivity, which has thus far prevented the use of these materials as active electrodes in EDLCs. Here, we show that Ni3(2,3,6,7,10,11-hexaiminotriphenylene)2 (Ni3(HITP)2), a MOF with high electrical conductivity, can serve as the sole electrode material in an EDLC. This is the first example of a supercapacitor made entirely from neat MOFs as active materials, without conductive additives or other binders. The MOF-based device shows an areal capacitance that exceeds those of most carbon-based materials and capacity retention greater than 90% over 10,000 cycles, in line with commercial devices. Given the established structural and compositional tunability of MOFs, these results herald the advent of a new generation of supercapacitors whose active electrode materials can be tuned rationally, at the molecular level.
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We present a simple and generalizable synthetic route toward phase-pure, monodisperse transition-metal-substituted ceria nanoparticles (M0.1Ce0.9O2-x, M = Mn, Fe, Co, Ni, Cu). The solution-based pyrolysis of a series of heterobimetallic Schiff base complexes ensures a rigorous control of the size, morphology and composition of 3 nm M0.1Ce0.9O2-x crystallites for CO oxidation catalysis and other applications. X-ray absorption spectroscopy confirms the dispersion of aliovalent (M(3+) and M(2+)) transition metal ions into the ceria matrix without the formation of any bulk transition metal oxide phases, while steady-state CO oxidation catalysis reveals an order of magnitude increase in catalytic activity with copper substitution. Density functional calculations of model slabs of these compounds confirm the stabilization of M(3+) and M(2+) in the lattice of CeO2. These results highlight the role of the host CeO2 lattice in stabilizing high oxidation states of aliovalent transition metal dopants that ordinarily would be intractable, such as Cu(3+), as well as demonstrating a rational approach to catalyst design. The current work demonstrates, for the first time, a generalizable approach for the preparation of transition-metal-substituted CeO2 for a broad range of transition metals with unparalleled synthetic control and illustrates that Cu(3+) is implicated in the mechanism for CO oxidation on CuO-CeO2 catalysts.
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BACKGROUND: The prognostic utility of comprehensive, guideline-defined assessment of diastolic measures during routine exercise echocardiography remains unclear. OBJECTIVES: The purpose of the study was to pragmatically assess the prognostic role of obtainable Doppler-derived diastolic variables during treadmill exercise echocardiography. METHODS: In this retrospective study, the authors included 1910 patients undergoing exercise echocardiography. The guideline-defined diastolic measures included resting septal e' velocity, post-exercise E/e' ratio and post-exercise tricuspid regurgitant jet velocity. Since tricuspid regurgitant jet velocity is not routinely obtainable, the authors examined 2 approaches: 2 variable approach using only resting septal e' velocity and post-exercise E/e' ratio and 3 variable approach with all diastolic variables. RESULTS: The mean age of study subjects was 57.6 ± 16 years and 1068 (56 %) were women. The tricuspid jet velocity was not reliably obtained in 501(26 %) of patients. All 3 diastolic variables were associated with the hard outcomes (mortality, acute coronary syndrome, cardiac hospitalization), soft outcomes (subsequent revascularization and cardiac testing), as well as the composite outcome. In the 2-variable approach, the presence of 2 abnormal variables was associated with a worse composite outcome. In the 3 variable approach, the presence of 2 or 3 abnormal variables was associated with a worse composite outcome. The associations persisted after multivariable adjustment and in the propensity matched subgroups. CONCLUSIONS: Guideline-defined diastolic variables during treadmill exercise echocardiography offer prognostic utility when used in combination, especially if all 3 variables are obtainable.
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Forcibly displaced populations experience an increased burden of mental illness. Scaling up mental health (MH) services places new resource demands on health systems in crises-affected settings and raises questions about how to provide equitable MH services for refugee and host populations. Our study investigates barriers, facilitators, and proposed solutions to MH financing and access for Lebanese populations and Syrian refugees in Lebanon, a protracted crisis setting. We collected qualitative data via 73 interviews and 3 focus group discussions. Participants were purposively selected from: (i) national, United Nations and NGO stakeholders; (ii) frontline MH service providers; (iii) insurance company representatives; (iv) Lebanese and Syrian adults and parents of children aged 12-17 years using MH services. Data were analysed using inductive and deductive approaches. Our results highlight challenges facing Lebanon's system of financing MH care in the face of ongoing multiple crises, including inequitable coverage, dependence on external humanitarian funds, and risks associated with short-term funding and their impact on sustainability of services. The built environment presents additional challenges to individuals trying to navigate, access and use existing MH services, and the social environment and service provider factors enable or hinder individuals accessing MH care. Registered Syrian refugees have better financial coverage to secondary MH care than Lebanese populations. However, given the economic crisis, both populations are facing similar challenges in paying for and accessing MH care at primary health care (PHC) level. Multiple crises in Lebanon have exacerbated challenges in financing MH care, dependence on external humanitarian funds, and risks and sustainability issues associated with short-term funding. Urgent reforms are needed to Lebanon's health financing system, working with government and external donors to equitably and efficiently finance and scale up MH care with a focus on PHC, and to reduce inequities in MH service coverage between Lebanese and Syrian refugee populations.
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While most coronavirus 2019 (COVID-19) survivors have had complete resolution of symptoms, a significant proportion have suffered from incomplete recovery. Cardiopulmonary symptoms, such as dyspnea, chest pain, and palpitations are responsible for a substantial symptom burden in COVID-19 survivors. Studies have revealed persistent myocardial injury with late gadolinium enhancement and myocardial scar on cardiac magnetic resonance in a significant proportion of patients. Evidence of myocardial edema, active inflammation, left ventricular dysfunction, and right ventricular dysfunction, is limited to a minority of patients. Large observational studies of COVID-19 survivors have indicated an increased risk of cardiovascular disease compared to the general population, including the risk of coronary artery disease, cardiomyopathy, and arrhythmias. Management of long COVID is focused on supportive therapy to reduce systemic inflammation. Patients with high cardiovascular risk, namely, those who had cardiovascular complications during acute illness, patients who have new onset cardiopulmonary symptoms in the postinfectious period, and competitive athletes, should be evaluated by a cardiovascular specialist. Management of cardiovascular sequelae is currently based on general expert guideline recommendations given the lack of evidence specific to long COVID syndrome. In this review, we outline the cardiovascular manifestations of long COVID, the current evidence supporting cardiac abnormalities in the postinfectious period, and the recommended management of these patients.
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There has been an increase in the evaluation and implementation of non-specialist delivered psychological interventions to address unmet mental health needs in humanitarian emergencies. While randomized controlled trials (RCTs) provide important evidence about intervention impact, complementary qualitative process evaluations are essential to understand key implementation processes and inform future scaling up of the intervention. This study was conducted as part of an RCT of the Early Adolescents Skills for Emotions (EASE) psychological intervention for young adolescents with elevated psychological distress (predominantly with a Syrian refugee background) in Lebanon. Our aims were firstly to conduct a qualitative process evaluation to understand stakeholder experiences and perceived impact of the intervention and identify barriers and facilitators for implementation, and secondly to explore considerations for scaling up. Eleven key informant interviews and seven focus groups were conducted with 39 respondents including adolescent and caregiver participants, trainers, providers, outreach workers, and local stakeholders. Data were analyzed using inductive and deductive thematic analysis. Respondents perceived the intervention to be highly needed and reported improvements in adolescent mental health and wellbeing. Key implementation factors that have potential to influence engagement, adherence, and perceived impact included the socio-economic situation of families, mental health stigma, coordination within and between sectors (particularly for scaling up), embedding the intervention within existing service pathways, having clear quality and accountability processes including training and supervision for non-specialists, and sustainable funding. Our findings provide important context for understanding effectiveness outcomes of the RCT and highlights factors that need to be considered when implementing a mental health intervention on a larger scale in a complex crisis.
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BACKGROUND: Adolescents growing up in communities characterised by adversity face multiple risk factors for poor mental health and wellbeing. There is currently a scarcity of research on effective approaches for preventing and treating psychological distress in this population, particularly in humanitarian settings. The powerful impact of the home environment and family support is well known; however, approaches targeting the family are seldom developed or evaluated in such settings. We developed a brief family systemic psychosocial support intervention to be delivered through existing child protection systems with non-specialist facilitators. This paper outlines the study protocol for a randomised controlled trial of the intervention in Lebanon. METHODS: We will conduct a single-blind hybrid effectiveness-implementation multi-site RCT comparing the locally developed systemic family intervention to a waitlist control group for families residing in vulnerable regions in North Lebanon and Beqaa governorates (including families of Syrian, Palestinian, and Lebanese backgrounds). Outcomes on a range of family, adolescent, and caregiver measures will be assessed at baseline (T0) and post-intervention (T1), and at a 3-month follow-up for the treatment arm (T2). Families will be eligible for the trial if they are identified by implementing organisations as being medium-to-high risk for child protection concerns and have one or more adolescent aged 12-17 who demonstrates significant psychological distress on a self-report brief screening tool. Families will be randomly assigned to a treatment or a waitlist control condition. Families in the waitlist condition will receive a group version of the programme after completion of the study, to allow us to assess feasibility, acceptability, and preliminary indications of intervention effects of this modality. The primary outcome is reduction in overall adolescent-reported psychological distress over time, with post-intervention (T1) as the primary endpoint. Secondary adolescent-reported outcomes include family functioning, psychosocial wellbeing, and emotional regulation difficulties. Secondary caregiver-reported outcomes include parenting style, family functioning, psychological distress, and emotional regulation difficulties. DISCUSSION: This trial will provide the first assessment of the effectiveness of the family systemic psychosocial support intervention for use in Lebanon, with important implications for the use of systemic, low-cost, non-specialist interventions for this age range. TRIAL REGISTRATION: Local registry: National Mental Health Program, Ministry of Public Health, Lebanese Republic. Registered on 19 October 2021 Lebanese Clinical Trial Registry LBCTR2021104870 . Registered on 13 October 2021 Global registry: ISRCTN ISRCTN13751677 . Registered on 1 November 2021.
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Poder Familiar , Sistemas de Apoio Psicossocial , Adolescente , Cuidadores/psicologia , Criança , Humanos , Líbano , Poder Familiar/psicologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Método Simples-CegoRESUMO
Recently, the discovery of biological and clinical properties of mutated isoforms 1 and 2 mutations of isocitrate dehydrogenases (IDH) 1 and 2, affecting approximately 20% of patients with acute myeloid leukemia (AML), lead to the development of an individualized treatment strategy. Promoting differentiation and maturation of the malignant clone targeting IDH is an emerging strategy to promote clinical responses in AML. Phase I/II trials have shown evidence of safety, tolerability, and encouraging evidence of efficacy of two small molecule inhibitors targeting IDH2 and IDH1 gene mutations, respectively enasidenib and ivosidenib. In this review, the contribution of IDH1/IDH2 mutations in leukemogenesis and progress of targeted therapeutics in AML will be highlighted.
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OBJECTIVES: To evaluate the practice of aminoglycoside use/monitoring in Kenya and explore healthcare worker (HCW) perceptions of aminoglycoside monitoring to identify gaps and opportunities for future improvements, given the low therapeutic index of aminoglycosides. METHODS: This was a two-phase study whereby we reviewed patients' medical records at Kenyatta National Hospital (October-December 2016) in Phase 1 and interviewed HCWs face to face in Phase 2. Outcome measures included describing and evaluating the practice of aminoglycoside use and monitoring and compliance to guidelines. Data were analysed using descriptive and inferential analysis. RESULTS: Overall, out of the 2318 patients admitted, 192 patients (8.3%) were prescribed an aminoglycoside, of which 102 (53.1%) had aminoglycoside doses that did not conform to national guidelines. Aminoglycoside-related adverse effects were suspected in 65 (33.9%) patients. Monitoring of aminoglycoside therapy was performed in only 17 (8.9%) patients, with no therapeutic drug monitoring (TDM), attributed mainly to knowledge and skill gaps and lack of resources. Out of the 28 recruited HCWs, 18 (64.3%) needed training in how to perform and interpret TDM results. CONCLUSIONS: The practice of using and monitoring aminoglycosides was suboptimal, raising concerns around potential avoidable harm to patients. The identified gaps could form the basis for developing strategies to improve the future use of aminoglycosides, not only in Kenya but also in other countries with similar settings and resources.
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Atrial fibrillation (AF) and cardiometabolic syndrome (CMS) have been linked to inflammation and fibrosis. However, it is still unknown which inflammatory cytokines contribute to the pathogenesis of AF. Furthermore, cardiometabolic syndrome (CMS) risk factors such as obesity, hypertension, insulin resistance/glucose intolerance are also associated with inflammation and increased level of cytokines and adipokines. We hypothesized that the inflammatory immune response is exacerbated in patients with both AF and CMS compared to either AF or CMS alone. We investigated inflammatory cytokines and fibrotic markers as well as cytokine genetic profiles in patients with lone AF and CMS. CMS, lone AF patients, patients with both lone AF and CMS, and control patients were recruited. Genetic polymorphisms in inflammatory and fibrotic markers were assessed. Serum levels of connective tissue growth factor (CTGF) were tested along with other inflammatory markers including platelet-to-lymphocyte ratio (PLR), monocyte-to-HDL ratio (MHR) in three groups of AF+CMS, AF, and CMS patients. There was a trend in the CTGF levels for statistical significance between the AF and AF+CMS group (P = 0.084). Genotyping showed high percentages of patients in all groups with high secretor genotypes of Interleukin-6 (IL-6) (P = 0.037). Genotyping of IFN-γ and IL-10 at high level showed an increase in expression in the AF + CMS group compared to AF and CMS alone suggesting an imbalance between the inflammatory and anti-inflammatory cytokines which is exacerbated by AF. Serum cytokine inflammatory cytokine levels showed that IL-4, IL-5, IL-10, IL-17F, and IL-22 were significant between the AF, AF+CMS, and CMS patients. Combination of both CMS and AF may be associated with a higher degree of inflammation than what is seen in either CMS or AF alone. Thus, the identification of a biomarker capable of identifying metabolic syndrome associated with disease will help in identification of a therapeutic target in treating this devastating disease.
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Gold electrocatalysts have been a research focus due to their ability to reduce CO2 into CO, a feedstock for further conversion. Many methods have been employed to modulate CO2 reduction (CDR) vs hydrogen evolution reaction (HER) selectivity on gold electrodes such as nano-/mesostructuring and crystal faceting control. Herein we show that gold surfaces with very different morphologies (planar, leaves, and wires) lead to similar bell-shaped CO faradaic efficiency as a function of applied potential. At low overpotential (E > -0.85 V vs standard hydrogen electrode (SHE)), HER is dominant via a potential quasi-independent rate that we attribute to a rate limiting process of surface dissociation of competent proton donors. As overpotential is increased, CO faradaic efficiency reaches a maximal value (near 90%) because CO production is controlled by an electron transfer rate that increases with potential, whereas HER remains almost potential independent. At high overpotential (E < -1.2 V vs SHE), CO faradaic efficiency decreases due to the concurrent rise of HER via bicarbonate direct reduction and leveling off of CDR as CO2 replenishment at the catalyst surface is limited by mass transport and homogeneous coupled reactions. Importantly, the analysis shows that recent attempts to overcome mass transport limitations with gas diffusion electrodes confront low carbon mass balance owing to the prominence of homogeneous reactions coupled to CDR. The comprehensive kinetics analysis of the factors defining CDR vs HER on gold electrodes developed here provides an activation-driving force relationship over a large potential window and informs on the design of conditions to achieve desirable high current densities for CO2 to CO conversion while maintaining high selectivity.
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BACKGROUND: Dendritic cell (DC) vaccine efficacy is directly related to the efficiency of DC migration to the lymph node after delivery to the patient. We discovered that a naturally occurring metabolite, sarcosine, increases DC migration in human and murine cells resulting in significantly improved anti-tumor efficacy. We hypothesized that sarcosine induced cell migration was due to chemokine signaling. METHODS: DCs were harvested from the bone marrow of wild type C57BL/6 mice and electroporated with tumor messenger RNA (mRNA). Human DCs were isolated from peripheral blood mononuclear cells (PBMCs). DCs were treated with 20 mM of sarcosine. Antigen specific T cells were isolated from transgenic mice and injected intravenously into tumor bearing mice. DC vaccines were delivered via intradermal injection. In vivo migration was evaluated by flow cytometry and immunofluorescence microscopy. Gene expression in RNA was investigated in DCs via RT-PCR and Nanostring. RESULTS: Sarcosine significantly increased human and murine DC migration in vitro. In vivo sarcosine-treated DCs had significantly increased migration to both the lymph nodes and spleens after intradermal delivery in mice. Sarcosine-treated DC vaccines resulted in significantly improved tumor control in a B16F10-OVA tumor flank model and improved survival in an intracranial GL261-gp100 glioma model. Gene expression demonstrated an upregulation of CXCR2, CXCL3 and CXCL1 in sarcosine- treated DCs. Further metabolic analysis demonstrated the up-regulation of cyclooxygenase-1 and Pik3cg. Sarcosine induced migration was abrogated by adding the CXCR2 neutralizing antibody in both human and murine DCs. CXCR2 neutralizing antibody also removed the survival benefit of sarcosine-treated DCs in the tumor models. CONCLUSION: Sarcosine increases the migration of murine and human DCs via the CXC chemokine pathway. This platform can be utilized to improve existing DC vaccine strategies.
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Vacinas Anticâncer/imunologia , Movimento Celular/efeitos dos fármacos , Movimento Celular/imunologia , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/fisiologia , Receptores CXCR/metabolismo , Sarcosina/farmacologia , Transdução de Sinais/efeitos dos fármacos , Transferência Adotiva , Animais , Biomarcadores , Modelos Animais de Doenças , Humanos , Imunoterapia , Camundongos , Neoplasias/imunologia , Neoplasias/metabolismo , Neoplasias/patologia , Neoplasias/terapia , Estresse Oxidativo , Receptores CXCR/genéticaRESUMO
The Clinical and Angiographic analysis with a Cobalt Alloy Coronary Stent (Driver) (CLASS) study was a prospective, nonrandomized, multicenter study designed to assess the safety and efficacy of a cobalt-chromium alloy-based stent in patients with stable or unstable angina pectoris. A total of 203 lesions were treated in 202 enrolled patients. The percentage of major adverse cardiac event-free patients was 87.6% (177 of 202) at 6 months (primary safety end point; major adverse cardiac events were defined as death, myocardial infarction, emergency bypass surgery, or target lesion revascularization [percutaneous transluminal coronary angioplasty or coronary artery bypass grafting]). The angiographic success rate (primary efficacy end point) was 100%, and the procedural success rate was 98%. The binary in-stent restenosis rate at 6 months was 12.6%. Our results have demonstrated that the Driver cobalt-chromium alloy stent can be used with a low 6-month incidence of major adverse cardiac events, a low 6-month binary restenosis rate, and high angiographic and procedural success rates.