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1.
J Vector Borne Dis ; 60(4): 453-456, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38174527

RESUMO

Background & objectives: Lutzomyia longipalpis sensu lato is an important vector of Leishmania infantum, the causative agent of visceral leishmaniasis (VL) in Latin America. In Mexico, this species has been recorded in endemic areas of leishmaniasis transmission, but it has never been detected as infected with Leishmania sp. This study aimed to explore the presence of Leishmania DNA in Lutzomyia longipalpis s.l. from samples collected with a human baited trap from an endemic region of leishmaniasis in southeastern Mexico. Methods: This is a prospective study where a total of 45 specimens of Lu. longipalpis s.l. collected in two sites of Yucatan state with records of leishmaniasis were tested. The nuclear ribosomal Internal Transcribed Spacer was amplified for the detection of Leishmania DNA. Results: Two females were positive for Leishmania DNA. None of the specimens positive for parasite DNA were found fed or gravid. Our finding represents the first record of infection by Leishmania in Lu. longipalpis s.l. for the country. Interpretation & conclusion: More studies are necessary to understand the potential role of this vector species in the transmission cycle of the causative agent of leishmaniasis in the southeastern and other regions of Mexico.


Assuntos
Leishmania infantum , Leishmaniose Visceral , Leishmaniose , Psychodidae , Animais , Feminino , Humanos , Psychodidae/parasitologia , México , Estudos Prospectivos , Insetos Vetores/parasitologia , Leishmaniose Visceral/epidemiologia , Leishmaniose/epidemiologia , Leishmania infantum/genética , DNA , Brasil/epidemiologia
2.
Chem Rec ; 21(10): 2837-2854, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33533538

RESUMO

The importance of gem-difunctionalized ketones is represented by their broad applications across chemical boundaries over recent years. The interesting reactivities that this class of compounds possess have made them ideal building blocks to access high-value organic molecules. Furthermore, the gem-difunctionalized ketone moiety has featured in numerous bioactive molecules. For these reasons, a plethora of routes to access such significant molecules have been developed by research groups worldwide - this account looks at delineating the synthesis of gem-difunctionalized ketones from carbonyl substrates, diazo compounds, sulfur ylides and alkynyl reactants.

3.
Phys Chem Chem Phys ; 23(34): 18678-18685, 2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34612405

RESUMO

We examine the effect of removing self-interaction error (SIE) on the calculation of molecular polarizabilities in the local spin density (LSDA) and generalized gradient approximations (GGA). To this end, we utilize a database of 132 molecules taken from a recent benchmark study [Hait and Head-Gordon, Phys. Chem. Chem. Phys., 2018, 20, 19800] to assess the influence of SIE on polarizabilities by comparing results with accurate reference data. Our results confirm that the general overestimation of molecular polarizabilities by these density functional approximations can be attributed to SIE. However, removing SIE using the Perdew-Zunger self-interaction-correction (PZ-SIC) method, implemented using the Fermi-Löwdin Orbital SIC approach, leads to an underestimation of molecular polarizabilities, showing that PZ-SIC overcorrects when combined with LSDA or GGA. Application of a recently proposed locally scaled SIC [Zope, et al., J. Chem. Phys., 2019, 151, 214108] is found to provide more accurate polarizabilities. We attribute this to the ability of the local scaling scheme to selectively correct for SIE in the regions of space where the correction is needed most.

4.
J Am Chem Soc ; 142(3): 1287-1299, 2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31885267

RESUMO

The ability to control the surface composition and morphology of alloy catalysts is critical for achieving high activity and durability of catalysts for oxygen reduction reaction (ORR) and fuel cells. This report describes an efficient surfactant-free synthesis route for producing a twisty nanowire (TNW) shaped platinum-iron (PtFe) alloy catalyst (denoted as PtFe TNWs) with controllable bimetallic compositions. PtFe TNWs with an optimal initial composition of ∼24% Pt are shown to exhibit the highest mass activity (3.4 A/mgPt, ∼20 times higher than that of commercial Pt catalyst) and the highest durability (<2% loss of activity after 40 000 cycles and <30% loss after 120 000 cycles) among all PtFe-based nanocatalysts under ORR or fuel cell operating conditions reported so far. Using ex situ and in situ synchrotron X-ray diffraction coupled with atomic pair distribution function (PDF) analysis and 3D modeling, the PtFe TNWs are shown to exhibit mixed face-centered cubic (fcc)-body-centered cubic (bcc) alloy structure and a significant lattice strain. A striking finding is that the activity strongly depends on the composition of the as-synthesized catalysts and this dependence remains unchanged despite the evolution of the composition of the different catalysts and their lattice constants under ORR or fuel cell operating conditions. Notably, dealloying under fuel cell operating condition starts at phase-segregated domain sites leading to a final fcc alloy structure with subtle differences in surface morphology. Due to a subsequent realloying and the morphology of TNWs, the surface lattice strain observed with the as-synthesized catalysts is largely preserved. This strain and the particular facets exhibited by the TNWs are believed to be responsible for the observed activity and durability enhancements. These findings provide new insights into the correlation between the structure, activity, and durability of nanoalloy catalysts and are expected to energize the ongoing effort to develop highly active and durable low-Pt-content nanowire catalysts by controlling their alloy structure and morphology.

5.
Phys Chem Chem Phys ; 20(48): 30466-30474, 2018 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-30507978

RESUMO

A theoretical study has been performed for deposited AumAgn (m + n = 1-6) clusters. The combined use of the Mexican Enhanced Genetic Algorithm (MEGA) and Density Functional Theory (DFT) calculations allows us to explore the potential energy surface and therefore, find the global minimum configuration for each composition. We have performed calculations of clusters deposited on defects (oxygen vacancies) known as F centers on MgO (100) surfaces. Our results show interesting differences in the geometries of the clusters upon deposition and as a consequence in their electronic properties. The combination of two metals with different electronegativities creates an inhomogeneous charge distribution on their exposed surface producing good conditions for a catalytic process to take place.

6.
Phys Chem Chem Phys ; 18(32): 22122-8, 2016 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-27444254

RESUMO

A comparative theoretical study has been performed of the gas phase and deposited AumRhn (4 ≤ m + n ≤ 6) clusters. The combined use of a genetic algorithm and Density Functional Theory (DFT) calculations allows us to explore the potential energy surface and, therefore, find efficiently and automatically the global minimum configuration for each composition. Our results show interesting effects on the geometries of the clusters on deposition. This occurs because the rhodium atoms (electronically) prefer to be in contact with the MgO surface, sometimes promoting planar clusters to become three-dimensional when deposited, and three-dimensional clusters in the gas phase to become two-dimensional. Together with the change in geometries, the magnetic moment is reduced from the gas phase, as the electrons rearrange themselves when the cluster interacts with the substrate.

7.
Arch Cardiol Mex ; 93(4): 464-475, 2023 06 27.
Artigo em Espanhol | MEDLINE | ID: mdl-37369192

RESUMO

Background: Obesity is a multifactorial disorder characterized by increased body adiposity with a wide prevalence in our country, at any age, and linked to major adverse consequences, including the development of heart disease. Cardiac rehabilitation (CR) programs are interdisciplinary interventions aimed not only at restoring the lost functionality of patients who have suffered a cardiovascular outcome, but also at correcting those risk factors that led to it and that interfere with its adaptive results. Obesity contributes to perpetuating heart disease risk and is often resistant to conventional lifestyle modifications. Objective: Establish guidelines in the recognition of obesity with care guidelines for patients with heart disease within CR programs and their interdisciplinary approach. Method: Through an extensive bibliographical review and after an interdisciplinary discussion, this document was prepared to establish a position on the approach to obesity in the context of CR programs in patients with heart disease. Results and conclusions: Our Society recognizes the interdisciplinary approach of our patients with obesity and heart disease in its primary and secondary prevention, urges precision in its diagnosis and assessment, recommends that its primary axis must be based in the first instance on lifestyle modifications (physical training, nutritional care and psycho-emotional intervention), while pharmacological therapy and bariatric surgery could be coadjuvants in optimizing the results in selected patients.


Antecedentes: La obesidad es un trastorno multifactorial caracterizado por un aumento en la adiposidad corporal, de amplia prevalencia en nuestro país, a cualquier edad y ligada a grandes consecuencias adversas, incluyendo el desarrollo de cardiopatías. Los programas de rehabilitación cardiaca (RC) son intervenciones interdisciplinarias encaminadas no solo a restaurar la funcionalidad perdida de los pacientes que han sufrido un desenlace cardiovascular, sino también a corregir aquellos factores de riesgo que lo propiciaron y que interfieren en los resultados adaptativos del mismo. La obesidad contribuye a perpetuar el riesgo de cardiopatía y suele ser resistente a las modificaciones del estilo de vida de manera convencional. Objetivo: Establecer pautas en el reconocimiento de la obesidad con directrices de atención al paciente con cardiopatía dentro de los programas de RC y su abordaje interdisciplinario. Método: A través de una extensiva revisión bibliográfica y después de una discusión interdisciplinaria, se elaboró el presente documento para fijar una postura sobre el abordaje de la obesidad en el contexto de los programas de RC en pacientes con cardiopatía. Resultados y conclusiones: Nuestra Sociedad reconoce el abordaje interdisciplinario de los pacientes con obesidad y cardiopatía en su prevención primaria y secundaria, insta a la precisión en su diagnóstico y valoración, y recomienda que su eje primario debe estar basado en primera instancia en las modificaciones del estilo de vida (entrenamiento físico, atención nutricional e intervención psicoemocional), en tanto que la terapia farmacológica y la cirugía bariátrica pudieran ser coadyuvantes en la optimización de los resultados en pacientes selectos.


Assuntos
Reabilitação Cardíaca , Cardiopatias , Humanos , Sobrepeso , Obesidade/complicações , Obesidade/terapia , Obesidade/epidemiologia , Fatores de Risco
8.
Ecol Evol ; 13(2): e9837, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36844667

RESUMO

The Bull Shark (Carcharhinus leucas) faces varying levels of exploitation around the world due to its coastal distribution. Information regarding population connectivity is crucial to evaluate its conservation status and local fishing impacts. In this study, we sampled 922 putative Bull Sharks from 19 locations in the first global assessment of population structure of this cosmopolitan species. Using a recently developed DNA-capture approach (DArTcap), samples were genotyped for 3400 nuclear markers. Additionally, full mitochondrial genomes of 384 Indo-Pacific samples were sequenced. Reproductive isolation was found between and across ocean basins (eastern Pacific, western Atlantic, eastern Atlantic, Indo-West Pacific) with distinct island populations in Japan and Fiji. Bull Sharks appear to maintain gene flow using shallow coastal waters as dispersal corridors, whereas large oceanic distances and historical land-bridges act as barriers. Females tend to return to the same area for reproduction, making them more susceptible to local threats and an important focus for management actions. Given these behaviors, the exploitation of Bull Sharks from insular populations, such as Japan and Fiji, may instigate local decline that cannot readily be replenished by immigration, which can in turn affect ecosystem dynamics and functions. These data also supported the development of a genetic panel to ascertain the population of origin, which will be useful in monitoring the trade of fisheries products and assessing population-level impacts of this harvest.

9.
Arch Cardiol Mex ; 2023 Jun 06.
Artigo em Espanhol | MEDLINE | ID: mdl-37355985

RESUMO

Introduction: In Mexico, cardiac rehabilitation (CR) as an interdisciplinary intervention with therapeutic impact in patients with heart disease is growing. There is the need to know actual conditions of CR in our country. Objectives: The objective of this National Registry is to follow-up those existing and new CR units in Mexico through the comparison between the two previous registries, RENAPREC-2009 and RENAPREC II-2015 studies. This is a descriptive study focused on diverse CR activities such as assistance training, and certification of health professionals, barriers, reference, population attended, interdisciplinarity, permanence over time, growth prospects, regulations, post-pandemic condition, integrative characteristics, and scientific research. Results: Data were collected from 45 CR centers in the 32 states, 75.5% are private practice units, 67% are new, 33% were part of RENAPREC II-2015, and 17 have continued since 2009. With a better distribution of CR units along the territory, the median reference of candidates for CR programs is 9% with a significant reduction into tiempo of enrollment to Phase II admission (19 ± 11 days). Regarding to previous registries, the coverance of Phases I, II, and III is 71%, 100%, and 93%, respectively; and a coverance increases in evaluation, risk stratification, and prescription, more comprehensive attendance and prevention strategies. Conclusions: CR in Mexico has grown in the past 7 years. Even there is still low reference and heterogeneity in specific processes, there are strengths such as interdisciplinarity, scientific professionalization of specialists, national diversification, and an official society that are consolidated over time.


Introducción: En México, la Rehabilitación Cardíaca (RC) como intervención interdisciplinaria con impacto terapéutico en paciente con cardiopatía está en crecimiento. Existe la necesidad de conocer las condiciones actuales de la RC en nuestro país. Objetivo: El objetivo de este Registro es dar seguimiento comparativo de las unidades nuevas y existentes entre los registros anteriores, RENAPREC-2009 y RENAPREC II-2015. Se trata de un estudio descriptivo centrado en diversas actividades de la RC: formación asistencial y certificación de sus profesionales, barreras, referencia, población atendida, interdisciplinariedad, permanencia en el tiempo, perspectivas de crecimiento, normativa, condición pospandemia, características integradoras e investigación. Resultados: Se recolectaron datos de 45 centros en los 32 estados, 67% son nuevos 75.5% son de práctica privada, 33% fueron parte de RENAPREC II-2015 y 17 desde 2009. Con una mejor distribución de las unidades de RC a lo largo del territorio, la mediana de referencia de pacientes candidatos a RC es ahora del 9% con reducción significativa del tiempo de admisión a Fase II (19 ± 11 días). Respecto a registros anteriores las coberturas de las Fases I, II y III son del 71%, 100% y 93%, respectivamente; con un aumento de la cobertura en evaluación, estratificación de riesgo y prescripción, atención más integral y estrategias de prevención. Conclusiones: La RC en México ha crecido en los últimos 7 años. Si bien aún existe baja referencia y heterogeneidad en procesos específicos, existen fortalezas como la interdisciplinariedad, la profesionalización científica de los especialistas, la diversificación nacional y una sociedad oficial que se consolida en el tiempo.

10.
Med Sci Educ ; 32(5): 1087-1094, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36117947

RESUMO

Introduction: The Cleveland-Cusco Connection (CCC) elective was created during the COVID-19 pandemic to continue global health (GH) education for Case Western Reserve University (CWRU) and Universidad Nacional de San Antonio Abad del Cusco (UNSAAC) medical students. The CCC elective was held over Zoom and aimed to promote international collaboration, knowledge about health systems, and perspectives in GH with synchronous and asynchronous learning. Methods: Peruvian and US medical students participated in six monthly sessions consisting of student presentations and large and small group discussions. The elective was led collaboratively by CWRU and UNSAAC students. We evaluated students' experience using pre- and post-course surveys. Results: Nineteen students (76%) completed the post-course survey. The median rating for meeting each course objective was "somewhat effective" on a 5-point scale ranging from "very ineffective" to "very effective." All respondents would recommend the course to a friend. Common barriers included language challenges, fatigue from other coursework, and technology issues. Seven students' pre- and post-course surveys could be linked. The number of students who agreed with the statements assessing course objectives increased for all questions between the pre- and post-test, with only the number agreeing that they understood the Peruvian healthcare system increasing significantly (p < 0.05). Discussion: The CCC elective provides a valuable GH educational opportunity via a virtual platform. Students reported that learning from their peers was effective and enjoyable. Conclusion: Virtual GH electives like the CCC may offer benefits in terms of cost, equity, and flexibility and merit further investigation. Supplementary Information: The online version contains supplementary material available at 10.1007/s40670-022-01626-6.

11.
Arch Cardiol Mex ; 92(4): 446-453, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36413696

RESUMO

OBJECTIVE: The myocardial efficiency index (MEI) correlates the Myocardial Oxygen Consumption (MVO2) with the Maximum Oxygen Consumption (VO2max), this index provides information about the cardiovascular efficiency (CVEf). In athletes, the MEI improves after a micro-cycle training, however in patients with cardiovascular disease undergoing Cardiac Rehabilitation Program (CRP), IEM behavior could be a good estimator related to the improvement training period. The objective of this study was to determine the myocardial efficiency index behavior in patients with heart disease and high cardiovascular risk (HCVR) after a CRP. METHODS: Ambilective, descriptive, analytical, non-randomized cohort study was conducted. Patients with heart disease of mixed etiology and HCVR admitted to a CRP for 4-6 weeks were selected. All patients performed a maximal exercise test in band before and after the CPR. Thresholds of VO2 peak, METs-load, Double product (DP) and MEI were determined. A cut-off point for the MEI was established using a ROC curve with a value of 7.37, area under the curve: 0.68 (95% CI 0.61 - 0.76, p < 0.001), sensitivity 0.60 and 1-specificity 0.35. RESULTS: 193 patients with a mean age of 62.3 years were included, predominantly men (66.2%). Percentages changes in the MEI-27.1% (p < 0.001),METs-43.1% (p < 0.001),DP 5.7% (p < 0.01), and MVO2: 8.3% (p < 0.01) were observed at the end of CRP. CONCLUSIONS: Significant change in the MEI were observed after CRP associated to CVEf improvement, suggesting that this parameter could be considered as a good clinical tool in the CRP care programs.


OBJETIVO: El índice de eficiencia miocárdica (IEM) correlaciona el consumo miocárdico de oxígeno (MVO2) con el consumo máximo de oxígeno, el cual proporciona información sobre la eficiencia cardiovascular (EfCV). En deportistas, el IEM mejora posterior a un microciclo de entrenamiento, en el paciente con enfermedad cardiovascular sometido a un programa de rehabilitación cardiaca y prevención secundaria PRHCyPS, el comportamiento del IEM podría resultar un estimador relacionado con mejoría derivado de un periodo de entrenamiento. El objetivo del estudio fue determinar el comportamiento del IEM posterior a un PRCyPS en pacientes con cardiopatías y riesgo cardiovascular alto (RCVA). MÉTODOS: Estudio de cohorte ambilectivo, descriptivo, analítico, no aleatorizado. Se seleccionaron pacientes con cardiopatías de etiología mixta con RCVA ingresados a un PRCyPS durante 4-6 semanas. A todos los pacientes se les realizó una prueba de ejercicio máximo en banda antes y después del PRCyPS. Se determinaron umbrales de consumo de oxígeno (VO2) pico, equivalentes metabólicos-carga, doble producto e IEM. Se estableció un punto de corte del IEM mediante una curva ROC con un valor de 7.37 con un área bajo la curva de 0.68 (IC 95%: 0.61-0.76; p < 0.001), sensibilidad 0.60 y 1-especificidad de 0.35. RESULTADOS: Se incluyeron 193 pacientes con una media de edad de 62.3 años, en su mayoría del sexo masculino (66.2%). Se observaron porcentajes de cambio en el IEM ­27.1% (p < 0.001), MET 43.1% (p < 0.001), doble producto 5.7% (p < 0.01) y MVO2: 8.3% (p < 0.01) al término del PRCyPS. CONCLUSIONES: Se observó un cambio significativo en el IEM posterior a un PRCyPS, lo cual se asoció a una mejoría en la EfCV, sugiriendo que este pueda considerarse como un parámetro clínico que evaluar en los programas de rehabilitación cardiaca.


Assuntos
Reabilitação Cardíaca , Cardiopatias , Masculino , Humanos , Pessoa de Meia-Idade , Feminino , Estudos de Coortes , Miocárdio , Teste de Esforço
12.
Arch Cardiol Mex ; 2022 Apr 04.
Artigo em Espanhol | MEDLINE | ID: mdl-35377577

RESUMO

Background: The cardiovascular sequelae by the SARS-COV-2 infection is prevalent in a significant portion of the recovered patients from the acute presentation of the SARS-COV-2. Actually, the clinic cardiac control of the post-acute COVID syndrome has been working out without a well-established protocol, making the appropriate diagnosis of the cardiac diseases produced by the different damage mechanisms from COVID-19. Objectives: Standardize cardiovascular care and the follow up of COVID-19 survivors in the function on disease severity and identify patients who develop SPC-19A for timely care. Materials and methods: Through an extensive bibliographic review, this article has the purpose of provide the necessary information to make possible the early diagnosis and following of the cardiac complications that has been recorded trough the months after the acute disease from COVID-19.


Antecedentes: Las secuelas cardiovasculares ocasionadas por la enfermedad por coronavirus 2019 (COVID-19) son frecuentes en una importante proporción de los pacientes recuperados del cuadro agudo de la enfermedad. Hasta el día de hoy el seguimiento cardiológico del síndrome agudo post-COVID-19 (SPC-19A) se ha realizado de forma heterogénea y sin directrices que permitan al clínico identificar oportunamente los cambios que preceden a enfermedades cardiológicas derivadas de los distintos mecanismos de daño inducidos por COVID-19. Objetivos: Estandarizar la atención y seguimiento cardiovascular de los supervivientes de COVID-19 en función de la gravedad de la enfermedad e identificar a los pacientes que desarrollen SPC-19A para su atención oportuna. Material y métodos: Mediante una revisión extensa de bibliografía, este documento tiene la intención de unificar y proporcionar la información necesaria para diagnosticar y dar seguimiento a las complicaciones cardiacas que se han documentado en los meses posteriores a la resolución de la COVID-19 aguda.

13.
Nat Commun ; 12(1): 859, 2021 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-33558516

RESUMO

Alloying noble metals with non-noble metals enables high activity while reducing the cost of electrocatalysts in fuel cells. However, under fuel cell operating conditions, state-of-the-art oxygen reduction reaction alloy catalysts either feature high atomic percentages of noble metals (>70%) with limited durability or show poor durability when lower percentages of noble metals (<50%) are used. Here, we demonstrate a highly-durable alloy catalyst derived by alloying PtPd (<50%) with 3d-transition metals (Cu, Ni or Co) in ternary compositions. The origin of the high durability is probed by in-situ/operando high-energy synchrotron X-ray diffraction coupled with pair distribution function analysis of atomic phase structures and strains, revealing an important role of realloying in the compressively-strained single-phase alloy state despite the occurrence of dealloying. The implication of the finding, a striking departure from previous perceptions of phase-segregated noble metal skin or complete dealloying of non-noble metals, is the fulfilling of the promise of alloy catalysts for mass commercialization of fuel cells.

14.
Arch Cardiol Mex ; 91(2): 178-185, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33887755

RESUMO

OBJECTIVE: Evaluate safety and effects of training at moderate and high intensity intervals (MIIT, HIIT) compared to continuous moderate intensity training (MICT) in heart disease patient with very high cardiovascular risk (CVR). METHOD: Quasi-experimental study of 81 patients in a cardiac rehabilitation (CR) program, after risk stratification, all patients presented at least 2 factors with high CVR. All patients were provided supervised concurrent training: aerobic: initially 2 weeks MICT. subsequently MICT group with same prescription, MIIT 3 intervals of 3 'to 70-80% FCR with active pause exercise of 3' to 60 a 70% FCR, HIIT 3 intervals of 3'a 80-90% FCR with active pause exercise of 3 '70 a 80% FCR, resistance training 3 weekly sessions isotonic exercises and 1 calisthenics and multidisciplinary intervention. RESULTS: 81 patients assigned to: 61 MICT group, 13 MIIT and 7 HIIT, no significant differences were observed. Percentage gains were obtained in METs-load 45%, 60% and 86% (p = 0.17) and watts 51, 44 and 48 in MICT, MIIT, HIIT respectively (p = 0.54). Although there are no statistical significant intergroup differences if there is a greater improvement in MET-load in the HIIT group. There was no adverse outcome in any training. CONCLUSIONS: In very high cardiovascular risk heart disease patient, supervised interval training (MIIT/HIIT) is safe, with a tendency to greater improvement in exercise tolerance (METs-load) with HIIT compared to MICT.


OBJETIVO: Evaluar la seguridad y el efecto del entrenamiento por intervalos de moderada y alta intensidad (EIMI, EIAI) y compararlo con el entrenamiento de intensidad moderada continua (EIMC) en pacientes de riesgo cardiovascular (RCV) muy alto. MÉTODO: Estudio cuasi experimental de 81 pacientes que ingresaron al programas de rehabilitación cardíaca y prevención secundaria (PRHCPS); en la estratificación de riesgo, todos los pacientes presentaron ≥ 2 factores de RCV alto. Entrenamiento concurrente: aeróbico supervisado: 2 semanas de entrenamiento de base de EIMC; luego el grupo EIMC con la misma prescripción, EIMI a 3 intervalos de 3' al 70 a 80% de FCR con pausas activas de 3' al 60 a 70% de FCR; EIAI, 3 intervalos de 3' a 80 a 90% de FCR con pausas activas de 3' al 70 a 80% de FCR, entrenamiento de fuerza con tres sesiones semanales de ejercicios isotónicos y una de calistenia e intervención multidisciplinaria. RESULTADOS: 81 pacientes asignados en tres grupos: 61 a EIMC, 13 a EIMI y 7 a EIAI, sin diferencias significativas en las variables epidemiológicas. Hubo ganancias porcentuales en MET-carga de 45%, 60% y 86% (p = 0.17) y carga-vatios de 51, 44 y 48 en EIMC, EIMI, EIAI, respectivamente (p = 0.54). A pesar de no existir diferencias estocásticamente significativas intergrupales, sí se registró una ganancia mayor en MET-carga en el grupo de EIAI. No se observó desenlace adverso en ningún tipo de entrenamiento. CONCLUSIONES: En cardiópatas de riesgo cardiovascular muy alto, el entrenamiento interválico EIMI/EIAI supervisado es seguro, con tendencia a mayor ganancia en tolerancia al esfuerzo (MET-carga) con el EIAI en comparación con el EIMC.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Tolerância ao Exercício , Cardiopatias , Treinamento Resistido/métodos , Fatores de Risco de Doenças Cardíacas , Humanos , Aptidão Física/fisiologia , Fatores de Risco
15.
Arch Cardiol Mex ; 91(Suplemento COVID): 102-109, 2021 Dec 20.
Artigo em Espanhol | MEDLINE | ID: mdl-33651787

RESUMO

The coronavirus disease 2019 (COVID-19) was declared a pandemic on March 11, 2020; one consequence has been the increase in sedentary lifestyle and reduction of sports activity. Exercise benefits the immune defense system especially in older adults; it is recommended to keep a distance of 1.5 meters between people, and if walking or jogging is carried out, the space must be up to 5 and 10 meters respectively. The reported cases are mostly mild up to 80% and can be critical in up to 4.7%; the risk factors are well known, hypertension, diabetes and previous heart disease. Severe or critical cases present as symptoms of acute respiratory distress syndrome, and in the case of cardiovascular disease, they mainly occur as myopericarditis, acute coronary syndromes, cardiogenic shock, thrombotic events, among others. Returning to exercise after recovery from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is always recommended, however it will depend on the clinical picture what measures should be taken prior to its onset, and it is in moderate cases and especially in the severe ones where the evaluation and prescription prior to returning to exercise or sport should be guided by medical personnel experts in cardiopulmonary rehabilitation, especially in athletes.


La enfermedad por coronavirus 2019 (COVID-19) fue declarada pandemia el 11 de marzo de 2020; una consecuencia ha sido el incremento en el sedentarismo y la reducción de la actividad deportiva. El ejercicio beneficia el sistema inmunitario de defensa, especialmente en adultos mayores. Se recomienda guardar distancia de 1.5 metros entre personas, y si se realiza caminata o trote, el espacio debe ser de hasta 5 y 10 metros respectivamente. Los casos reportados son en su mayoría leves hasta en un 80%, y pueden ser críticos hasta en 4.7%; los factores de riesgo son bien conocidos: hipertensión, diabetes y enfermedad cardiaca previa. Los casos graves o críticos se presentan como cuadros de síndrome de distrés respiratorio agudo y ante afección cardiovascular cursan principalmente como miopericarditis, síndromes coronarios agudos, choque cardiogénico y eventos trombóticos, entre otros. El ejercicio después de la recuperación de infección por coronavirus 2 del síndrome respiratorio agudo grave (SARS-CoV-2) siempre está recomendado, sin embargo, dependerá del cuadro clínico qué medidas se deben tomar previo a su inicio, y es en casos moderados y especialmente en los graves donde la evaluación y prescripción previa al retorno al ejercicio o deporte debe ser guiada por personal médico experto en rehabilitación cardiopulmonar, en especial en deportistas.


Assuntos
COVID-19 , Volta ao Esporte , Reabilitação Cardíaca , Cardiologia , Humanos , México , Pandemias
16.
AMIA Jt Summits Transl Sci Proc ; 2020: 201-210, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32477639

RESUMO

Individuals increasingly rely on social media to discuss health-related issues. One way to provide easier access to relevant in- formation is through sentiment analysis - classifying text into polarity classes such as positive and negative. In this paper, we generated freely available datasets of WebMD.com drug reviews and star ratings for Common, Cancer, Depression, Diabetes, and Hypertension drugs. We explored four supervised learning models: Naive Bayes, Random Forests, Support Vector Machines, and Convolutional Neural Networks for the purpose of determining the polarity of drug reviews. We conducted inter-domain and cross-domain evaluations. We found that SVM obtained the highest f-measure on average and that cross-domain training produced similar or higher results to models trained directly on their respective datasets.

17.
Nanoscale ; 12(30): 16173-16188, 2020 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-32701100

RESUMO

The syntheses of metal nanoparticles by reduction in apolar solvents in the presence of long chain surfactants have proven to be extremely effective in the control of the particle size and shape. Nevertheless, the elucidation of the nucleation/growth mechanism is not straightforward because of the multiple roles played by surfactants. The nucleation stage, in particular, is very difficult to describe precisely and requires in situ and time-resolved techniques. Here, relying on in situ small angle X-ray scattering (SAXS), X-ray absorption spectroscopy (XAS) and high-energy X-ray diffraction (HE-XRD), we propose that ultra-small gold particles prepared by reduction of gold chloride in a solution of oleylamine (OY) in hexane with triisopropylsilane do not follow a classical nucleation process but result from pre-nucleation clusters (PNCs). These PNCs contain Au(iii) and Au(i) precursors; they are almost stable in size during the induction stage, as shown by SAXS, prior to undergoing a very fast shrinkage during the nucleation stage. The gold speciation as a function of time deduced from the XAS spectra has been analyzed through multi-step reaction pathways comprising both highly reactive species, involved in the nucleation and growth stages, and poorly reactive species acting as a reservoir for the reactive species. The duration of the induction period is related to the reactivity of the gold precursors, which is tuned by the coordination of OY to the gold complexes, while the nucleation stage was found to depend on the size and reactivity of the PNCs. The role of the PNCs in determining the final particle size and structure is also discussed in relation to previous studies. The multiple roles of OY, as the solubilizing agent of the gold salt, the ligand of the gold complexes determining both the size of the PNCs and the reactivity of the gold precursors, and finally the capping agent of the final gold particles as oleylammonium chloride, have been clearly established. This work opens new perspectives to synthesize metal NPs via metal-organic PNCs and to define new synthesis routes for nanoparticles that may present structure and morphologies different from those obtained by the classical nucleation routes.

18.
Arch Cardiol Mex ; 91(2): 190-195, 2020 08 05.
Artigo em Espanhol | MEDLINE | ID: mdl-33008149

RESUMO

Objetivo: La insuficiencia cardiaca (IC) es un síndrome clínico caracterizado por disminución en la capacidad funcional. Los programas de rehabilitación cardiaca y prevención secundaria (PRHCyPS) han mostrado mejorar la calidad de vida y tolerancia al esfuerzo en este grupo de pacientes, pero sus efectos son dependientes del volumen. Nuestro objetivo es evaluar el grado de correlación del volumen de entrenamiento medido en equivalentes metabólicos (MET)-min/semana con el porcentaje de ganancia de consumo pico de oxígeno (VO2p) (MET-carga) posterior a un PRHCyPS en pacientes con IC. Método: Estudio cuasiexperimental que evaluó la ganancia de VO2p (MET-carga) en 31 pacientes posterior a un PRHCyPS, antes y después de una prueba de ejercicio convencional, que consistió en 30 min de entrenamiento dinámico al 70% frecuencia cardíaca de reserva (FCR) durante seis semanas, así como entrenamiento de kinesioterapia e intervención interdisciplinaria. Se calculó el volumen de entrenamiento de cada paciente en MET-min/semana (método de Kaminsky). Se midió el índice de correlación con Rho de Spearman y se consideró significancia estocástica con valor de p < 0.05. Resultados: El 70.6% fueron de sexo masculino, promedio de edad 61.5 ± 8.9 años, con fracción de expulsión del ventrículo izquierdo promedio de 38 ± 4.6%; el 96.8% de la IC fue de origen isquémico; un 55.9, un 29.4 y un 5.9% en clase funcional según la New York Heart Association I, II y III, respectivamente. Con un volumen de entrenamiento promedio de 504.34 ± 164 MET-min/semana. La mayor correlación se obtuvo en las poblaciones de alto riesgo, con una Rho: 0.486 (p = 0.008) por VO2p-carga. Conclusiones: Si bien existe una ganancia sustancial en tolerancia al esfuerzo medido por VO2p-carga, no obtuvimos suficiente grado de correlación entre el volumen de entrenamiento aplicado y la ganancia obtenida.

19.
Nanoscale ; 11(12): 5512-5525, 2019 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-30860531

RESUMO

Catalysts for energy related applications, in particular metallic nanoalloys, readily undergo atomic-level changes during electrochemical reactions. The origin, dynamics and implications of the changes for the catalysts' activity inside fuel cells though are not well understood. This is largely because they are studied on model nanoalloy structures under controlled laboratory conditions. Here we use combined synchrotron X-ray spectroscopy and total scattering to study the dynamic behaviour of nanoalloys of Pt with 3d-transition metals as they function at the cathode of an operating proton exchange membrane fuel cell. Results show that the composition and atomic structure of the nanoalloys change profoundly, from the initial state to the active form and further along the cell operation. The electrocatalytic activity of the nanoalloys also changes. The rate and magnitude of the changes may be rationalized when the limits of traditional relationships used to connect the composition and structure of nanoalloys with their electrocatalytic activity and stability, such as Vegard's law, are recognized. In particular, deviations from the law inherent for Pt-3d metal nanoalloys can well explain their behaviour under operating conditions. Moreover, it appears that factors behind the remarkable electrocatalytic activity of Pt-3d metal nanoalloys, such as the large surface to unit volume ratio and "size misfit" of the constituent Pt and 3d-transition metal atoms, also contribute to their instability inside fuel cells. The new insight into the atomic-level evolution of nanoalloy electrocatalysts during their lifetime is likely to inspire new efforts to stabilize transient structure states beneficial to their activity and stability under operating conditions, if not synthesize them directly.

20.
Medicine (Baltimore) ; 98(19): e15620, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31083258

RESUMO

RATIONALE: Diffusion tensor imaging (DTI), diffusion tensor tractography (DTT), as well as resting-state-functional magnetic resonance imaging (rsfMRI) are promising methods for assessing patients with disorders of consciousness (DOCs). PATIENT CONCERNS: This work describes the main findings using DTI, DTT, and rsfMRI in a patient with a DOC secondary to an anoxic encephalopathy who had a fatal outcome. She was an 85-year-old woman who presented a cardiac arrest and underwent cardiopulmonary resuscitation for 20 minutes then returning to spontaneous circulation. After sedation withdrawal, 2 days after the event, she remained with a Glasgow Coma Scale score of 3/15 and with an absence of brainstem reflexes. DIAGNOSES: DOC secondary to an anoxic encephalopathy after cardiovascular resuscitation. INTERVENTIONS: A complete brain MRI scan was performed 72 hours after the initial event, including DTI, DTT, and rsfMRI. DTT demonstrated disruption of both ventral and dorsal tegmental tracts bilaterally. DTI showed a reduction of fractional anisotropic level in the mesencephalic nuclei. Moreover, changes in the number of fiber tracts were not evidenced in any portions of the ascending reticular activating system (ARAS). Finally, an increase in the anticorrelated and correlated association among the nuclei in the ARAS and the cortex was evidenced. OUTCOMES: Patient deceased. LESSONS: Neuroimaging demonstrated low FA values in the ARAS, destruction of dorsal and ventral tegmental tracts, as well as hyper-connective (highly correlated or anti-correlated) association among ARAS and cortical nuclei compared with 3 healthy control subjects.


Assuntos
Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Transtornos da Consciência/diagnóstico por imagem , Transtornos da Consciência/fisiopatologia , Parada Cardíaca/complicações , Imageamento por Ressonância Magnética , Idoso de 80 Anos ou mais , Transtornos da Consciência/etiologia , Evolução Fatal , Feminino , Neuroimagem Funcional , Parada Cardíaca/diagnóstico por imagem , Parada Cardíaca/fisiopatologia , Humanos , Imageamento por Ressonância Magnética/métodos , Vias Neurais/diagnóstico por imagem , Vias Neurais/fisiopatologia
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