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1.
Respirar (Ciudad Autón. B. Aires) ; 16(1): 5-15, Marzo 2024.
Artículo en Español | LILACS, UNISALUD, BINACIS | ID: biblio-1538330

RESUMEN

Objetivos: Millones de pacientes con COVID-19 fueron internados en terapia intensiva en el mundo, la mitad desarrollaron síndrome de dificultad respiratoria aguda (SDRA) y recibieron ventilación mecánica invasiva (VMI), con una mortalidad del 50%. Analiza-mos cómo edad, comorbilidades y complicaciones, en pacientes con COVID-19 y SDRA que recibieron VMI, se asociaron con el riesgo de morir durante su hospitalización.Métodos: Estudio de cohorte observacional, retrospectivo y multicéntrico realizado en 5 hospitales (tres privados y dos públicos universitarios) de Argentina y Chile, durante el segundo semestre de 2020.Se incluyeron pacientes >18 años con infección por SARS-CoV-2 confirmada RT-PCR, que desarrollaron SDRA y fueron asistidos con VMI durante >48 horas, durante el se-gundo semestre de 2020. Se analizaron los antecedentes, las comorbilidades más fre-cuentes (obesidad, diabetes e hipertensión), y las complicaciones shock, insuficiencia renal aguda (IRA) y neumonía asociada a la ventilación mecánica (NAV), por un lado, y las alteraciones de parámetros clínicos y de laboratorio registrados.Resultados: El 69% era varón. La incidencia de comorbilidades difirió para los diferentes grupos de edad. La mortalidad aumentó significativamente con la edad (p<0,00001). Las comorbilidades, hipertensión y diabetes, y las complicaciones de IRA y shock se asociaron significativamente con la mortalidad. En el análisis multivariado, sólo la edad mayor de 60 años, la IRA y el shock permanecieron asociados con la mortalidad. Conclusiones: El SDRA en COVID-19 es más común entre los mayores. Solo la edad >60 años, el shock y la IRA se asociaron a la mortalidad en el análisis multivariado.


Objectives: Millions of patients with COVID-19 were admitted to intensive care world-wide, half developed acute respiratory distress syndrome (ARDS) and received invasive mechanical ventilation (IMV), with a mortality of 50%. We analyzed how age, comor-bidities and complications in patients with COVID-19 and ARDS who received IMV were associated with the risk of dying during their hospitalization.Methods: Observational, retrospective and multicenter cohort study carried out in 5 hospitals (three private and two public university hospitals) in Argentina and Chile, during the second half of 2020.Patients >18 years of age with SARS-CoV-2 infection confirmed by RT-PCR, who devel-oped ARDS and were assisted with IMV for >48 hours, during the second half of 2020, were included. History, the most frequent comorbidities (obesity, diabetes and hyper-tension) and the complications of shock, acute renal failure (AKI) and pneumonia as-sociated with mechanical ventilation (VAP), on the one hand, and the alterations of re-corded clinical and laboratory parameters, were analyzed.Results: 69% were men. The incidence of comorbidities differed for different age groups. Mortality increased significantly with age (p<0.00001). Comorbidities, hyper-tension and diabetes, and complications of ARF and shock were significantly associat-ed with mortality. In the multivariate analysis, only age over 60 years, ARF and shock remained associated with mortality.Conclusions: ARDS in COVID-19 is more common among the elderly. Only age >60 years, shock and ARF were associated with mortality in the multivariate analysis


Asunto(s)
Humanos , Masculino , Femenino , Adolescente , Adulto , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Neumonía/complicaciones , Respiración Artificial/métodos , Síndrome de Dificultad Respiratoria del Recién Nacido/complicaciones , Choque/complicaciones , Comorbilidad , Insuficiencia Renal/complicaciones , SARS-CoV-2 , COVID-19/epidemiología , Argentina/epidemiología , Chile/epidemiología , Factores de Riesgo , Mortalidad , Estudio Multicéntrico
2.
Microsc Res Tech ; 2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38380821

RESUMEN

Utilizing radio frequency magnetron sputtering, we successfully fabricated nickel oxide thin films with different thickness (from 80 to 270 nm), and conducted an in-depth examination of their structural, morphological, optical, and electrical properties. The crystal structure and surface roughness were determined using x-ray diffraction (XRD) and atomic force microscopy (AFM), respectively. The XRD analyses showed that the films were composed of cubic nickel oxide, exhibiting a notable orientation along the (200) direction. This crystal texture partially increased when the film thickness reached 270 nm. In addition, a direct correlation between film thickness and crystallite size was observed, with the latter increasing as the former did. AFM analysis provided insights into the surface morphology, revealing metrics like the bearing area, 3D surfaces intersections, and statistical properties of surface height. These insights underscore the relationship between film thickness and surface properties, which in turn influence the overall electrical, and prominently, optical properties of the films. Employing transmittance UV-visible spectroscopy, we characterized the optical behavior of these films, noting a proportional increase in refractive index with film thickness. Additionally, resistivity was observed to increase concomitantly with film thickness. In conclusion, the deposition process's film thickness acts as a pivotal parameter for fine-tuning the structural, morphological, and optical properties of nickel oxide thin films. This knowledge paves the way for optimizing nickel oxide-based devices across various applications. RESEARCH HIGHLIGHTS: We synthesized and characterized of p-type semiconducting NiO thin films sputtered on substrates by using RF magnetron sputtering with different thickness. Advanced crystalline structures and fractal features extracted from XRD and AFM analysis.  The 2D and 3D surface analysis of the samples indicates a complex structure with an imperfect self-similarity that suggests a multifractal structure. We represented graphically the relative representation of higher geometric objects in the AFM image. We attributed the optical and electrical properties of the samples to the crystallite size, and the concurrent reduction in oxygen vacancies and crystalline defects within the films.

3.
Polymers (Basel) ; 16(3)2024 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-38337308

RESUMEN

The development of polymeric biocomposites containing natural fibers has grown over the years due to the properties achieved and its eco-friendly nature. Thus, biocomposites involving a polymer from a renewable source (Biopolyethylene (BioPE)) and babassu fibers (BFs), compatibilized with polyethylene grafted with maleic anhydride (MA) and acrylic acid (AA) (PE-g-MA and PE-g-AA, respectively) were obtained using melt mixing and injection molded into tensile, impact, and HDT specimens. Babassu fiber was characterized with Fourier transform infrared spectroscopy (FTIR), thermogravimetry (TGA), and scanning electron microscopy (SEM). The biocomposites were characterized using torque rheometry, TGA, tensile strength, impact strength, thermomechanical properties, Shore D hardness, and SEM. The data indicate that the torque during the processing of compatibilized biocomposites was higher than that of BioPE/BF biocomposites, which was taken as an indication of a possible reaction between the functional groups. Compatibilization led to a substantial improvement in the elastic modulus, tensile strength, HDT, and VST and a decrease in Shore D hardness. These results were justified with SEM micrographs, which showed babassu fibers better adhered to the surface of the biopolyethylene matrix, as well as an encapsulation of these fibers. The system investigated is environmentally sustainable, and the results are promising for the technology of polymeric composites.

4.
Arch Cardiol Mex ; 2024 Feb 21.
Artículo en Español | MEDLINE | ID: mdl-38382332

RESUMEN

Atrial fibrillation (AF) is the most prevalent arrhythmia and is related with significant morbidity, mortality and costs. In spite of relevant advances in the prevention of embolic events and rhythm control, little has been done to reduce its prevalence, progression and impact, since it increases with ageing as well as with common risk factors such as alcohol intake, tobacco use and stress as well as with arterial hypertension, diabetes mellitus, heart failure, sleep apnea, kidney failure, chronic pulmonary obstructive disease, ischemic heart disease and stroke, among other important comorbidities. Fortunately, new evidence suggests that lifestyle modifications and adequate risk factors and comorbidities control could be effective in primary and secondary AF prevention, especially in its paroxysmal presentations. This is why a multidisciplinary approach integrating lifestyle modifications, risk factors and comorbidities control, is necessary in conjunction with rhythm or rate control and anticoagulation. Unfortunately, that holistic approach strategy is not considered, is scarcely studied or is subtilized in general clinical practice. The present statement's objectives are to: 1) review the relationship between habits, risk factors and illnesses with AF, 2) review the individual and common physiopathology mechanisms of each one of those conditions that may lead to AF, 3) review the effect of control of habits, risk factors and co-morbidities on the control and impact of AF, and 4) supply guidelines and recommendations to start multidisciplinary and integrative AF treatment.


La fibrilación auricular (FA) es la arritmia más frecuente y se asocia con importante morbilidad, mortalidad y costos. A pesar de los grandes avances en la prevención de eventos embólicos y en el control del ritmo, poco se ha realizado para reducir su prevalencia, progresión e impacto, debido a que incrementa con la edad y con la presencia de múltiples factores de riesgo muy comunes en la población, como obesidad, sedentarismo, alcoholismo, tabaquismo y estrés, así como con hipertensión arterial sistémica, diabetes mellitus, insuficiencia cardiaca, apnea del sueño, enfermedad renal crónica, enfermedad pulmonar obstructiva crónica, cardiopatía isquémica y enfermedad vascular cerebral, entre otra comorbilidad importante. Afortunadamente, nuevas evidencias demuestran que las modificaciones en el estilo de vida y el control adecuado de los factores de riesgo y de la comorbilidad pueden ser efectivos en la prevención primaria y secundaria de la FA, en especial en sus formas paroxísticas; para ello, es necesario un manejo multidisciplinario que integre las modificaciones en el estilo de vida, el manejo de los factores de riesgo y el control de la comorbilidad en el tratamiento de la FA en conjunto con el control del ritmo o de la frecuencia y la anticoagulación. Por desgracia, en la práctica clínica estas estrategias a menudo no se tienen en cuenta, son infrautilizadas y poco estudiadas. Los objetivos del presente posicionamiento son: 1) revisar la relación de los factores de riesgo y la comorbilidad con la FA, 2) revisar los mecanismos fisiopatológicos de cada una de estas condiciones, 3) revisar el impacto del control de los factores de riesgo y de la comorbilidad en el control y en el impacto de la FA, y 4) proporcionar guías y recomendaciones para la puesta en práctica de programas de tratamiento multidisciplinario e integral en pacientes con FA.

5.
Chemosphere ; 352: 141406, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38367881

RESUMEN

2,4,6-Trinitrotoluene (TNT) is a highly toxic nitroaromatic explosive known for its environmental consequences, contaminating soil and groundwater throughout its life cycle, from production to disposal. Therefore, the urgency of developing innovative and ecological strategies to remedy the affected areas is recognized. This study reports, for the first time, the enzymatic biotransformation of TNT by a cocktail of native laccases from Pycnoporus sanguineus CS43. The laccases displayed efficient TNT conversion under both oxygenic and non-oxygenic conditions, achieving biotransformation rates of 80% and 87% within 48 h at a temperature of 60 °C and pH 7. Preliminary kinetic constants were calculated with the laccase cocktail, being a Vmax of 1.133 µM min-1 and 0.2984 µM min-1, and the Km values were 1586 µM and 458 µM, in an oxygenic and non-oxygenic atmosphere, respectively. High-performance liquid chromatography-mass spectrometry (HPLC/MS) confirmed the formation of amino dinitrotoluene isomers and hydroxylamine isomers as biotransformation products. In summary, this study suggests the potential application of laccases for the direct biotransformation of recalcitrant compounds like TNT, offering an environmentally friendly approach to address contamination issues.


Asunto(s)
Polyporaceae , Trinitrotolueno , Lacasa/química , Biotransformación , Polyporaceae/metabolismo
6.
Medicina (B Aires) ; 84(1): 108-124, 2024.
Artículo en Español | MEDLINE | ID: mdl-38271938

RESUMEN

Adult smokers, those with comorbidities, and the elderly, are at greater risk of contracting infections and their complications. Community acquired respiratory infections due to viruses, pneumococcus and other bacteria, affect both healthy and sick adults. There are vaccines that the pulmonologist must know and prescribe. The target strains of the influenza vaccine are defined by the WHO for the Southern hemisphere considering those involved in the previous influenza season in the Northern hemisphere. Its effectiveness depends on virulence, concordance between circulating and vaccine strains, and population coverage. The anti-pneumococcal polysaccharide vaccine available since 1983 is being replaced by more effective conjugate vaccines to prevent infections related to serotypes present in them. Immunization against SARS-CoV-2 reduced the contagion, severity, and lethality of COVID-19. The acellular vaccine against Bordetella pertussis for adults is present for specific situations in the adult calendar; vaccinating them strengthens the control of childhood contagion. The double (diphtheria + tetanus), and triple (double + pertussis) bacterial vaccines, and the vaccines against measles, chickenpox, rubella, human papillomavirus, Haemophilus influenzae, meningococcus, herpes zoster, Argentine hemorrhagic fever and yellow fever, are of a more limited use. Soon we will have new vaccines such as the one recently approved by the FDA against respiratory syncytial virus. Through a consensus of experts in respiratory infections, we review the new evidence regarding the immunization of adults who consult a pulmonologist, and thus update the recommendations on vaccination made eight years ago.


Los adultos fumadores con comorbilidades, y los ancianos, corren mayor riesgo de contraer infecciones y sus complicaciones. Las infecciones respiratorias comunitarias por virus, neumococo y otras bacterias afectan tanto a adultos sanos como enfermos. Existen vacunas que el neumonólogo debe conocer y prescribir. Las cepas blanco de la vacuna contra influenza son definidas por la OMS para el hemisferio sur considerando a las implicadas en la temporada precedente de influenza en el hemisferio norte. Su efectividad depende de la virulencia, la concordancia entre las cepas circulantes y las vacunales y la cobertura de la población. La vacuna anti-neumocócica polisacárida disponible desde 1983 está siendo reemplazada por vacunas conjugadas más eficaces para prevenir infecciones relacionadas a serotipos presentes en las mismas. La inmunización contra SARS-CoV-2 redujo el contagio, la gravedad y la letalidad de COVID-19. La vacuna acelular contra Bordetella pertussis para adultos está presente para situaciones puntuales en el calendario para adultos, vacunarlos fortalece el control del contagio infantil. Las vacunas doble bacteriana (difteria + tétanos), y triple (doble + pertussis), y contra sarampión, varicela, rubeola, virus del papiloma humano, Haemophylus influenzae, meningococo, herpes zóster, fiebre hemorrágica argentina y fiebre amarilla, son de uso más limitado. Pronto contaremos con nuevas vacunas, como la recientemente aprobada por la FDA contra el virus sincicial respiratorio. Revisamos a través de un consenso de expertos en infecciones respiratorias las nuevas evidencias acerca de la inmunización de adultos que consultan al neumonólogo, y actualizamos así las recomendaciones sobre vacunación realizadas ocho años atrás.


Asunto(s)
COVID-19 , Vacunas contra la Influenza , Neumología , Adulto , Humanos , Lactante , Anciano , Vacunación , Vacunas Neumococicas , COVID-19/prevención & control
7.
Biochimie ; 216: 46-55, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37879428

RESUMEN

Mycobacteria are microorganisms distributed in the environment worldwide, and some of them, such as Mycobacterium tuberculosis or M. leprae, are pathogenic. The hydrophobic mycobacterial cell envelope has low permeation and bacteria need to export products across their structure. Mycobacteria possess specialized protein secretion systems, such as the Early Secretory Antigenic Target 6 secretion (ESX) system. Five ESX loci have been described in M. tuberculosis, called ESX-1 to ESX-5. The ESX-3 secretion system has been associated with mycobacterial metabolism and growth. The locus of this system is highly conserved across mycobacterial species. Metallo-proteins regulate negative ESX-3 transcription in high conditions of iron and zinc. Moreover, this secretion system is part of an antioxidant regulatory pathway linked to Zinc. EccA3, EccB3, EccC3, EccD3, and EccE3 are components of the ESX-3 secretion machinery, whereas EsxG-EsxH, PE5-PPE4, and PE15-PPE20 are proteins secreted by this system. In addition, EspG3 and MycP3 are complementary proteins involved in transport and proteolysis respectively. This system is associated to mycobacterial virulence by releasing the bacteria from the phagosome and inhibiting endomembrane damage response. Furthermore, components of this system inhibit the host immune response by reducing the recognition of M. tuberculosis-infected cells. The components of the ESX-3 secretion system play a role in drug resistance and cell wall integrity. Moreover, the expression data of this system indicated that external and internal factors affect ESX-3 locus expression. This review provides an overview of new findings on the ESX-3 secretion system, its regulation, expression, and functions.


Asunto(s)
Mycobacterium tuberculosis , Tuberculosis , Sistemas de Secreción Tipo VII , Humanos , Sistemas de Secreción Tipo VII/genética , Sistemas de Secreción Tipo VII/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Mycobacterium tuberculosis/metabolismo , Zinc/metabolismo
8.
Int J Mol Sci ; 24(19)2023 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-37833855

RESUMEN

In this work, polyhydroxybutyrate (PHB) was maleic anhydride (MA)-grafted in the molten state, using dicumyl peroxide (DCP) as a reaction initiator. Tin(II) 2-ethylhexanoate (Sn(Oct)2) and styrene monomer (St.) were used to maximize the maleic anhydride grafting degree. When PHB was modified with MA/DCP and MA/DCP/Sn(Oct)2, viscosity was reduced, suggesting chain scission in relation to pure PHB. However, when the styrene monomer was added, the viscosity increased due to multiple grafts of MA and styrene into the PHB chain. In addition, the FTIR showed the formation of a new band at 1780 cm-1 and 704 cm-1, suggesting a multiphase copolymer PHB-g-(St-co-MA). The PHB (MA/DCP) system showed a grafting degree of 0.23%; however, the value increased to 0.39% with incorporating Sn(Oct)2. The highest grafting efficiency was for the PHB (MA/DCP/St.) system with a value of 0.91%, while the PHB (MA/DCP/St./Sn(Oct)2) hybrid mixture was reduced to 0.73%. The chemical modification process of PHB with maleic anhydride increased the thermal stability by about 20 °C compared with pure PHB. The incorporation of 0.5 phr of the Sn(Oct)2 catalyst increased the efficiency of the grafting degree in the PHB. However, the St./Sn(Oct)2 hybrid mixture caused a deleterious effect on the maleic anhydride grafting degree.


Asunto(s)
Anhídridos Maleicos , Estireno , Polímeros , Fenómenos Químicos
9.
Polymers (Basel) ; 15(18)2023 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-37765677

RESUMEN

Polyphenols called procyanidins can be extracted from agro-industrial waste like litchi peel and coffee pulp. However, their efficacy is limited due to instability, which hinders both the bioavailability and preservation of their activity. This study aims to establish the ideal encapsulation conditions required to preserve the procyanidin properties found in extracts taken from litchi peel and coffee pulp. To attain the maximum procyanidin encapsulation efficacy (EE), the Taguchi method was utilized to streamline the spray-drying conditions for different wall materials-maltodextrin (MD), whey protein (WP), citrus pectin (CP), and skim milk (SM). The optimized conditions consisted of feed flow (3, 4.5, and 6 mL/min), temperature (125, 150, and 175 °C), and airflow (30, 35, and 40 m3/h). The microcapsules were characterized using ABTS, DPPH, lipoperoxidation, and scanning electron microscopy. Objective evaluations revealed that MD was the most effective encapsulation material for the litchi extract, whereas WP was the optimal option for the coffee extract. Of all the factors considered in the spray-drying process, feed flow had the strongest impact. The spray-drying process for the litchi peel extracts achieved high procyanidin encapsulation efficiencies at a feed flow rate of 4.5 mL/min, a temperature of 150 °C, and an airflow rate of 35 m3/h. Meanwhile, the coffee extract spray drying achieved similar results at a feed flow rate of 4.5 mL/min, a temperature of 175 °C, and an airflow rate of 40 m3/h. Encapsulation efficiencies of 98.1% and 93.6% were observed for the litchi and coffee extracts, respectively, under the mentioned optimal conditions. The microencapsulation process was successful in preserving the antioxidant properties of procyanidins. The microcapsules' size ranged from 2.6 to 3.2 micrometers. The results imply that the phenolic compounds present in the extracts function as effective antioxidant agents.

10.
Polymers (Basel) ; 15(16)2023 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-37631490

RESUMEN

In this work, blends based on poly (lactic acid) (PLA)/acrylonitrile-butadiene-styrene (ABS) compatibilized with maleic anhydride-grafted (SEBS-g-MA) were prepared in a co-rotational twin-screw extruder by varying the concentrations of the compatibilizing agent. The influence of the compatibilizing agent on the morphology, mechanical, thermal, thermomechanical, and rheological properties of the prepared materials was analyzed. The effect of annealing on the properties of the blends was also investigated using injection-molded samples. The X-ray diffraction (XRD) results proved that the increments in crystallinity were an effect of annealing in the PLA/ABS/SEBS-g-MA blends, resonating at higher heat deflection temperatures (HDTs). The impact strength of the PLA/ABS blends compatibilized with 10 wt% SEBS-g-MA was significantly increased when compared to the PLA/ABS blends. However, the hardness and elastic modulus of the blends decreased when compared to neat PLA. The refined morphology shown in the scanning electron microscopy (SEM) analyses corroborated the improved impact strength promoted by SEBS-g-MA. The torque rheometer degradation study also supported the increased compatibility between SEBS-g-MA, PLA, and ABS. The TGA results show that the PLA/ABS and PLA/ABS/SEBS-g-MA blends are more thermally stable than the neat PLA polymer at higher temperatures. The results showed that the ideal composition is the heat-treated PLA/ABS/SEBS-g-MA (60/30/10 wt%), given the high impact strength and HDT results. The results of this work in terms of mechanical improvement with the use of compatibilizers and annealing suggest that the PLA/ABS/SEBS-g-MA system can be used in the production of 3D-printing filaments.

11.
PLoS Negl Trop Dis ; 17(7): e0011270, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37399197

RESUMEN

BACKGROUND: The four Dengue viruses (DENV) serotypes were re-introduced in Brazil's Northeast region in a couple of decades, between 1980's and 2010's, where the DENV1 was the first detected serotype and DENV4 the latest. Zika (ZIKV) and Chikungunya (CHIKV) viruses were introduced in Recife around 2014 and led to large outbreaks in 2015 and 2016, respectively. However, the true extent of the ZIKV and CHIKV outbreaks, as well as the risk factors associated with exposure to these viruses remain vague. METHODS: We conducted a stratified multistage household serosurvey among residents aged between 5 and 65 years in the city of Recife, Northeast Brazil, from August 2018 to February 2019. The city neighborhoods were stratified and divided into high, intermediate, and low socioeconomic strata (SES). Previous ZIKV, DENV and CHIKV infections were detected by IgG-based enzyme linked immunosorbent assays (ELISA). Recent ZIKV and CHIKV infections were assessed through IgG3 and IgM ELISA, respectively. Design-adjusted seroprevalence were estimated by age group, sex, and SES. The ZIKV seroprevalence was adjusted to account for the cross-reactivity with dengue. Individual and household-related risk factors were analyzed through regression models to calculate the force of infection. Odds Ratio (OR) were estimated as measure of effect. PRINCIPAL FINDINGS: A total of 2,070 residents' samples were collected and analyzed. The force of viral infection for high SES were lower as compared to low and intermediate SES. DENV seroprevalence was 88.7% (CI95%:87.0-90.4), and ranged from 81.2% (CI95%:76.9-85.6) in the high SES to 90.7% (CI95%:88.3-93.2) in the low SES. The overall adjusted ZIKV seroprevalence was 34.6% (CI95%:20.0-50.9), and ranged from 47.4% (CI95%:31.8-61.5) in the low SES to 23.4% (CI95%:12.2-33.8) in the high SES. The overall CHIKV seroprevalence was 35.7% (CI95%:32.6-38.9), and ranged from 38.6% (CI95%:33.6-43.6) in the low SES to 22.3% (CI95%:15.8-28.8) in the high SES. Surprisingly, ZIKV seroprevalence rapidly increased with age in the low and intermediate SES, while exhibited only a small increase with age in high SES. CHIKV seroprevalence according to age was stable in all SES. The prevalence of serological markers of ZIKV and CHIKV recent infections were 1.5% (CI95%:0.1-3.7) and 3.5% (CI95%:2.7-4.2), respectively. CONCLUSIONS: Our results confirmed continued DENV transmission and intense ZIKV and CHIKV transmission during the 2015/2016 epidemics followed by ongoing low-level transmission. The study also highlights that a significant proportion of the population is still susceptible to be infected by ZIKV and CHIKV. The reasons underlying a ceasing of the ZIKV epidemic in 2017/18 and the impact of antibody decay in susceptibility to future DENV and ZIKV infections may be related to the interplay between disease transmission mechanism and actual exposure in the different SES.


Asunto(s)
Fiebre Chikungunya , Virus Chikungunya , Virus del Dengue , Dengue , Epidemias , Microcefalia , Infección por el Virus Zika , Virus Zika , Humanos , Preescolar , Niño , Adolescente , Adulto Joven , Adulto , Persona de Mediana Edad , Anciano , Brasil/epidemiología , Estudios Seroepidemiológicos , Microcefalia/epidemiología
12.
Polymers (Basel) ; 15(11)2023 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-37299276

RESUMEN

Epoxidation of castor oil in synthetic and enzymatic routes was carried out in order to promote a system with less environmental impact. The epoxidation reactions of castor oil compounds upon addition of lipase enzyme with and without acrylic immobilization and with reaction times of 24 and 6 h, as well as the synthetic compounds upon addition of Amberlite resin and formic acid, were investigated using Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance in hydrogen molecules (1H-NMR). The analysis indicated that the enzymatic reactions (6 h) and synthetic reactions provided a conversion from 50 to 96% and epoxidation from 25 to 48%, resulting from peak stretching and signal disintegration in the hydroxyl region due to the appearance of H2O in the interaction of peracid with catalyst. In systems without toluene, a dehydration event with a peak absorbance of 0.02 AU, indicating a possible vinyl group at 2355 cm-1 in enzymatic reactions without acrylic immobilization, was observed and resulted in a selectivity of 2%. In the absence of a solid catalyst, an unsaturation conversion of castor oil above 90% was achieved; however, this catalyst is necessary for the epoxidation to take place, whereas the lipase enzyme becomes able of epoxidizing and dehydrating the castor oil upon changing the time or reaction system. The conversation from 28 to 48% of solid catalysts (Amberlite and lipase enzyme) displays their importance to the instauration conversion of castor oil into oxirane rings.

14.
Viruses ; 15(5)2023 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-37243259

RESUMEN

CONTEXT: We reviewed what has been studied and published during the last 3 years about the consequences, mainly respiratory, cardiac, digestive, and neurological/psychiatric (organic and functional), in patients with COVID-19 of prolonged course. OBJECTIVE: To conduct a narrative review synthesizing current clinical evidence of abnormalities of signs, symptoms, and complementary studies in COVID-19 patients who presented a prolonged and complicated course. METHODS: A review of the literature focused on the involvement of the main organic functions mentioned, based almost exclusively on the systematic search of publications written in English available on PubMed/MEDLINE. RESULTS: Long-term respiratory, cardiac, digestive, and neurological/psychiatric dysfunction are present in a significant number of patients. Lung involvement is the most common; cardiovascular involvement may happen with or without symptoms or clinical abnormalities; gastrointestinal compromise includes the loss of appetite, nausea, gastroesophageal reflux, diarrhea, etc.; and neurological/psychiatric compromise can produce a wide variety of signs and symptoms, either organic or functional. Vaccination is not associated with the emergence of long-COVID, but it may happen in vaccinated people. CONCLUSIONS: The severity of illness increases the risk of long-COVID. Pulmonary sequelae, cardiomyopathy, the detection of ribonucleic acid in the gastrointestinal tract, and headaches and cognitive impairment may become refractory in severely ill COVID-19 patients.


Asunto(s)
COVID-19 , Humanos , COVID-19/complicaciones , Diarrea , Progresión de la Enfermedad , Síndrome Post Agudo de COVID-19 , Pronóstico , SARS-CoV-2
15.
Int J Mol Sci ; 24(8)2023 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-37108198

RESUMEN

Tuning and controlling the magnetic properties of nanomaterials is crucial to implement new and reliable technologies based on magnetic hyperthermia, spintronics, or sensors, among others. Despite variations in the alloy composition as well as the realization of several post material fabrication treatments, magnetic heterostructures as ferromagnetic/antiferromagnetic coupled layers have been widely used to modify or generate unidirectional magnetic anisotropies. In this work, a pure electrochemical approach has been used to fabricate core (FM)/shell (AFM) Ni@(NiO,Ni(OH)2) nanowire arrays, avoiding thermal oxidation procedures incompatible with integrative semiconductor technologies. Besides the morphology and compositional characterization of these core/shell nanowires, their peculiar magnetic properties have been studied by temperature dependent (isothermal) hysteresis loops, thermomagnetic curves and FORC analysis, revealing the existence of two different effects derived from Ni nanowires' surface oxidation over the magnetic performance of the array. First of all, a magnetic hardening of the nanowires along the parallel direction of the applied magnetic field with respect their long axis (easy magnetization axis) has been found. The increase in coercivity, as an effect of surface oxidation, has been observed to be around 17% (43%) at 300 K (50 K). On the other hand, an increasing exchange bias effect on decreasing temperature has been encountered when field cooling (3T) the oxidized Ni@(NiO,Ni(OH)2) nanowires below 100 K along their parallel lengths.


Asunto(s)
Nanoporos , Nanocables , Nanocables/química , Óxido de Aluminio , Níquel/química , Nanotecnología/métodos
16.
Eur Respir J ; 61(4)2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-37012080

RESUMEN

BACKGROUND: Severe community-acquired pneumonia (sCAP) is associated with high morbidity and mortality, and while European and non-European guidelines are available for community-acquired pneumonia, there are no specific guidelines for sCAP. MATERIALS AND METHODOLOGY: The European Respiratory Society (ERS), European Society of Intensive Care Medicine (ESICM), European Society of Clinical Microbiology and Infectious Diseases (ESCMID) and Latin American Thoracic Association (ALAT) launched a task force to develop the first international guidelines for sCAP. The panel comprised a total of 18 European and four non-European experts, as well as two methodologists. Eight clinical questions for sCAP diagnosis and treatment were chosen to be addressed. Systematic literature searches were performed in several databases. Meta-analyses were performed for evidence synthesis, whenever possible. The quality of evidence was assessed with GRADE (Grading of Recommendations, Assessment, Development and Evaluation). Evidence to Decision frameworks were used to decide on the direction and strength of recommendations. RESULTS: Recommendations issued were related to diagnosis, antibiotics, organ support, biomarkers and co-adjuvant therapy. After considering the confidence in effect estimates, the importance of outcomes studied, desirable and undesirable consequences of treatment, cost, feasibility, acceptability of the intervention and implications to health equity, recommendations were made for or against specific treatment interventions. CONCLUSIONS: In these international guidelines, ERS, ESICM, ESCMID and ALAT provide evidence-based clinical practice recommendations for diagnosis, empirical treatment and antibiotic therapy for sCAP, following the GRADE approach. Furthermore, current knowledge gaps have been highlighted and recommendations for future research have been made.


Asunto(s)
Enfermedades Transmisibles , Neumonía , Humanos , Neumonía/diagnóstico , Neumonía/terapia , Cuidados Críticos , Unidades de Cuidados Respiratorios
17.
Intensive Care Med ; 49(6): 615-632, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37012484

RESUMEN

PURPOSE: Severe community-acquired pneumonia (sCAP) is associated with high morbidity and mortality, and whilst European and non-European guidelines are available for community-acquired pneumonia, there are no specific guidelines for sCAP. METHODS: The European Respiratory Society (ERS), European Society of Intensive Care Medicine (ESICM), European Society of Clinical Microbiology and Infectious Diseases (ESCMID), and Latin American Thoracic Association (ALAT) launched a task force to develop the first international guidelines for sCAP. The panel comprised a total of 18 European and four non-European experts, as well as two methodologists. Eight clinical questions for sCAP diagnosis and treatment were chosen to be addressed. Systematic literature searches were performed in several databases. Meta-analyses were performed for evidence synthesis, whenever possible. The quality of evidence was assessed with GRADE (Grading of Recommendations, Assessment, Development and Evaluation). Evidence to Decision frameworks were used to decide on the direction and strength of recommendations. RESULTS: Recommendations issued were related to diagnosis, antibiotics, organ support, biomarkers and co-adjuvant therapy. After considering the confidence in effect estimates, the importance of outcomes studied, desirable and undesirable consequences of treatment, cost, feasibility, acceptability of the intervention and implications to health equity, recommendations were made for or against specific treatment interventions. CONCLUSIONS: In these international guidelines, ERS, ESICM, ESCMID, and ALAT provide evidence-based clinical practice recommendations for diagnosis, empirical treatment, and antibiotic therapy for sCAP, following the GRADE approach. Furthermore, current knowledge gaps have been highlighted and recommendations for future research have been made.


Asunto(s)
Enfermedades Transmisibles , Neumonía , Humanos , Neumonía/diagnóstico , Neumonía/tratamiento farmacológico , Cuidados Críticos
18.
Artículo en Inglés | MEDLINE | ID: mdl-36875964

RESUMEN

Most transradial prosthesis users with conventional "Sequential" myoelectric control have two electrode sites which control one degree of freedom (DoF) at a time. Rapid EMG co-activation toggles control between DoFs (e.g., hand and wrist), providing limited function. We implemented a regression-based EMG control method which achieved simultaneous and proportional control of two DoFs in a virtual task. We automated electrode site selection using a short-duration (90 s) calibration period, without force feedback. Backward stepwise selection located the best electrodes for either six or 12 electrodes (selected from a pool of 16). We additionally studied two, 2-DoF controllers: "Intuitive" control (hand open-close and wrist pronation-supination controlled virtual target size and rotation, respectively) and "Mapping" control (wrist flexion-extension and ulnar-radial deviation controlled virtual target left-right and up-down movement, respectively). In practice, a Mapping controller would be mapped to control prosthesis hand open-close and wrist pronation-supination. Eleven able-bodied subjects and 4 limb-absent subjects completed virtual target matching tasks (fixed target moves to a new location after being "matched," and subject immediately pursues) and fixed (static) target tasks. For all subjects, both 2-DoF controllers with 6 optimally-sited electrodes had statistically better target matching performance than Sequential control in number of matches (average of 4-7 vs. 2 matches, p< 0.001) and throughput (average of 0.75-1.25 vs. 0.4 bits/s, p< 0.001), but not overshoot rate and path efficiency. There were no statistical differences between 6 and 12 optimally-sited electrodes for both 2-DoF controllers. These results support the feasibility of 2-DoF simultaneous, proportional myoelectric control.

19.
J Electromyogr Kinesiol ; 69: 102753, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36731399

RESUMEN

Bilateral movement is widely used for calibration of myoelectric prosthesis controllers, and is also relevant as rehabilitation therapy for patients with motor impairment and for athletic training. Target tracking and/or force matching tasks can be used to elicit such bilateral movement. Limited descriptive accuracy data exist in able-bodied subjects for bilateral target tracking or dominant vs non-dominant dynamic force matching tasks requiring more than one degree of freedom (DoF). We examined dynamic trajectory (0.75 Hz band-limited, white, uniform random) constant-posture, hand open-close, wrist pronation-supination target tracking and matching tasks. Tasks were normalized to maximum voluntary contraction (MVC), spanning a ± 30% MVC force range, in four 1-DoF and 2-DoF tasks: (1, 2) unilateral dominant limb tracking with/without visual feedback, and (3, 4) bilateral dominant/non-dominant limb tracking with mirror visual feedback. In 12 able-bodied subjects, unilateral tracking error with visual feedback averaged 10-15 %MVC, but up to 30 %MVC without visual feedback. Bilateral matching error averaged âˆ¼10 %MVC and was affected little by visual feedback type, so long as feedback was provided. In 1-DoF bilateral tracking, the dominant side had statistically lower error than the non-dominant side. In 2-DoF bilateral tracking, the side providing mirror visual feedback exhibited lower error than the opposite side. In 2-DoF tasks (assumed to be more challenging than their constituent 1-DoF tracking tasks), hand grip force errors grew disproportionately larger than those of each wrist DoF. In unilateral 1-DoF tasks, both hand vs target and wrist vs target latency averaged 250-350 ms. In unilateral 2-DoF tasks, wrist vs target latency also averaged 250-350 ms, while hand vs target latency averaged > 500 ms. These results provide guidance on bilateral 2-DoF hand-wrist performance in target tracking, and dominant vs non-dominant force matching tasks.


Asunto(s)
Fuerza de la Mano , Muñeca , Humanos , Muñeca/fisiología , Fuerza de la Mano/fisiología , Músculo Esquelético/fisiología , Extremidad Superior , Mano/fisiología
20.
Polymers (Basel) ; 15(2)2023 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-36679237

RESUMEN

Using Kraft lignin, bio-based adhesives have been increasingly studied to replace those petrochemical-based solutions, due to low cost, easy availability and the potential for biodegradability of this biomaterial. In this study, lignin-based phenol-formaldehyde (LPF) resins were synthesized using commercial Eucalypt Kraft Lignin (EKL), purified at 95%, as a phenol substitute in different proportions of 10%, 20%, 30% and 50%. The properties of bio-based phenol formaldehyde (BPF) synthesized resin were compared with phenol-formaldehyde resin (PF) used for control sampling. The results indicated that viscosity, gel time and solid contents increased with the addition of pure EKL. The shear strength test of glue line was studied according to American Society for Testing and Materials (ASTM), and BPF-based results were superior to samples bonded with the PF as a control sample, being suitable for structural purposes. Changes in the curing behavior of different resins were analyzed by Differential Scanning Calorimetry (DSC), and sample comparison indicated that the curing of the LPF resin occurred at lower temperatures than the PF. The addition of EKL in PF reduced its thermal stability compared to traditional resin formulation, resulting in a lower decomposition temperature and a smaller amount of carbonaceous residues.

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