RESUMO
Population-wide vaccination is the most promising long-term COVID-19 disease management strategy. However, the protection offered by the currently available COVID-19 vaccines wanes over time, requiring boosters to be periodically given, which represents an unattainable challenge, especially if it is necessary to apply several doses per year. Therefore, it is essential to design strategies that contribute to maximizing the control of the pandemic with the available vaccines. Achieving this objective requires knowing, as precisely and accurately as possible, the changes in vaccine effectiveness over time in each population group, considering the eventual dependence on age, sex, etc. Thus, the present work proposes a novel approach to calculating realistic effectiveness profiles against symptomatic disease. In addition, this strategy can be adapted to estimate realistic effectiveness profiles against hospitalizations or deaths. All such time-dependent profiles allow the design of improved vaccination schedules, where each dose can be administrated to the population groups so that the fulfillment of the containment objectives is maximized. As a practical example for this analysis, vaccination against COVID-19 in Mexico was considered. However, this methodology can be applied to other countries' data or to characterize future vaccines with time-dependent effectiveness values. Since this strategy uses aggregated observational data collected from massive databases, assumptions about the data validity and the course of the studied epidemic could eventually be necessary.
RESUMO
A ferrofluid with 1,2-Benzenediol-coated iron oxide nanoparticles was synthesized and physicochemically analyzed. This colloidal system was prepared following the typical co-precipitation method, and superparamagnetic nanoparticles of 13.5 nm average diameter, 34 emu/g of magnetic saturation, and 285 K of blocking temperature were obtained. Additionally, the zeta potential showed a suitable colloidal stability for cancer therapy assays and the magneto-calorimetric trails determined a high power absorption density. In addition, the oxidative capability of the ferrofluid was corroborated by performing the Fenton reaction with methylene blue (MB) dissolved in water, where the ferrofluid was suitable for producing reactive oxygen species (ROS), and surprisingly a strong degradation of MB was also observed when it was combined with H2O2. The intracellular ROS production was qualitatively corroborated using the HT-29 human cell line, by detecting the fluorescent rise induced in 2,7-dichlorofluorescein diacetate. In other experiments, cell metabolic activity was measured, and no toxicity was observed, even with concentrations of up to 4 mg/mL of magnetic nanoparticles (MNPs). When the cells were treated with magnetic hyperthermia, 80% of cells were dead at 43 °C using 3 mg/mL of MNPs and applying a magnetic field of 530 kHz with 20 kA/m amplitude.
Assuntos
Coloides/química , Coloides/farmacologia , Hipertermia Induzida/métodos , Nanopartículas Magnéticas de Óxido de Ferro/química , Espécies Reativas de Oxigênio/metabolismo , Catecóis/química , Linhagem Celular , Coloides/síntese química , Citotoxinas/síntese química , Citotoxinas/química , Citotoxinas/farmacologia , Humanos , Concentração de Íons de Hidrogênio , Magnetismo , Microscopia Eletrônica de Transmissão , Oxidantes/síntese química , Oxidantes/química , Oxidantes/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Difração de Raios XRESUMO
Trichoderma species are fungi widely employed as plant-growth-promoting agents and for biological control. Several commercial and laboratory-made solid formulations for mass production of Trichoderma have been reported. In this study, we evaluated a solid kaolin-based formulation to promote the absortion/retention of Trichoderma asperellum in the substrate for growing tomato plants. The unique implementation of this solid formulation resulted in an increased growth of the tomato plants, both in roots and shoots after 40 days of its application. Plants were challenged with two fungal pathogens, Fusarium oxysporum and Botrytis cinerea, and pretreatment with T. asperellum resulted in less severe wilting and stunting symptoms than non-treated plants. Treatment with T. asperellum formulation inhibited Reactive Oxygen Species (ROS) production in response to the pathogens in comparison to plants that were only challenged with both pathogens. These results suggest that decrease in ROS levels contribute to the protective effects exerted by T. asperellum in tomato.
Assuntos
Botrytis/fisiologia , Fusarium/fisiologia , Doenças das Plantas/microbiologia , Espécies Reativas de Oxigênio/metabolismo , Solanum lycopersicum/microbiologia , Trichoderma/fisiologia , Solanum lycopersicum/anatomia & histologia , Solanum lycopersicum/fisiologia , Doenças das Plantas/prevenção & controle , Fatores de ProteçãoRESUMO
La enfermedad Pulmonar Obstructiva Crónica (EPOC), causa importante de muerte en los paises desarrollados (ocupa el cuarto lugar en EUA), es tan ó más frecuente en países en desarrollo. La exacerbación aguda de la enfermedad (EABC) causa número importante de hospitalizaciones y consultas. Un paciente con EPOC presenta de una a tres EABC por año, el número de exacerbaciones es marcador de severidad de la condición y determina la calidad de vida y mortalidad del paciente, 3 a 16% de casos se hospitalizan. La mortalidad hospitalaria es elevada, 10% en casos de EPOC severos y mayor si el paciente ingresa a una Unidad de Cuidado Intensivo. La etiología subyacente en la descompensación de un paciente co EPOC, es infecciosa, (hasta 80%), otras condiciones como Embolia Pulmonar, Neutórax, Isuficiencia Cardíaca, Fracturas en la caja torácica e Infecciones no pulmonares, descompensan también al paciente. La prevención de la exacerbación es un objetivo principal de la EPOC, en la actualidad las medidas que pueden disminuir la frecuencia de EABC se ha incrementado y existe evidencia que sustenta intervenciones de tipo preventivo eficaces. Estas medidas pueden ser farmacológicas, están disponibles para el beneficio de nuestros pacientes. El paciente con EABC debe recibir tratamiento proporcional a la severidad de su condición, se debe tratar las comorbilidades y instalar desde el momento agudo el inicio de la estrategia preventiva para el futuro. La presencia de EABC es un evento que puede deberse a múltiples causas, por lo que un enfoque individual del paciente es primordial.
Assuntos
Doença Pulmonar Obstrutiva Crônica , Doença Pulmonar Obstrutiva Crônica/etiologia , Doença Pulmonar Obstrutiva Crônica/prevenção & controleRESUMO
The immune and the circadian systems interact in a bidirectional fashion. The master circadian oscillator, located in the suprachiasmatic nuclei (SCN) of the hypothalamus, responds to peripheral and local immune stimuli, such as proinflammatory cytokines and bacterial endotoxin. Astrocytes exert several immune functions in the CNS, and there is growing evidence that points toward a role of these cells in the regulation of circadian rhythms. The aim of this work was to assess the response of SCN astrocytes to immune stimuli, particularly to the proinflammatory cytokine TNF-α. TNF-α applied to cultures of SCN astrocytes from Per2(luc) knockin mice altered both the phase and amplitude of PER2 expression rhythms, in a phase-dependent manner. Furthermore, conditioned media from SCN astrocyte cultures transiently challenged with TNF-α induced an increase in Per1 expression in NIH 3T3 cells, which was blocked by TNF-α antagonism. In addition, these conditioned media could induce phase shifts in SCN PER2 rhythms and, when administered intracerebroventricularly, induced phase delays in behavioral circadian rhythms and SCN activation in control mice, but not in TNFR-1 mutants. In summary, our results show that TNF-α modulates the molecular clock of SCN astrocytes in vitro, and also that, in response to this molecule, SCN astrocytes can modulate clock gene expression in other cells and tissues, and induce phase shifts in a circadian behavioral output in vivo. These findings suggest a role for astroglial cells in the alteration of circadian timing by immune activation.
Assuntos
Astrócitos/imunologia , Astrócitos/metabolismo , Relógios Circadianos/fisiologia , Núcleo Supraquiasmático/citologia , Fator de Necrose Tumoral alfa/metabolismo , Animais , Linhagem Celular , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Células NIH 3T3 , Proteínas Circadianas Period/biossíntese , Proteínas Circadianas Period/metabolismo , Receptores Tipo I de Fatores de Necrose Tumoral/genéticaRESUMO
Introducción: el asma es una enfermedad crónica con alta morbilidad a nivel mundial. La Aspergilosis broncopulmonar alérgica (ABPA) es un desorden alérgico causado por hipersensibilidad al Aspergillues fumigatus, y en estadios avanzados produce gran deterioro de la estructura y función pulmonar. Objetivo: describir, por primera vez en el país, las caractetísticas clínicas, radiológicas e inmunológicas de pacientes con Aspergilosis broncopulmonar alérgica (ABPA). Pacientes y método: pacientes ambulatorios con asma que fueron diagnosticados de ABPA entre el 2007 y 2009, en un Hospital general y una clínica privada (Lima, Perú). El estudio es observacional de tipo serie de casos. Resultados: encontramos 6 pacientes que fueron diagnosticados de ABPA 4 de sexo femenino, entre 7 y45 años de edad, 5 en estadio III. Conclusiones: se evidencia la presencia de ABPA en nuestro país y el 100 por ciento de los casos encontrados fueron diagnosticados en estadios avanzados de la enfermedad.
Asthma is a chronic disease with high morbidity worldwide. Allergic bronchopulmonary Aspergilosis (ABPA) is an allergic disorder caused by hypersensivity to Aspergillus fumigates. In advanced stages causes great damage to the lung structure and function. Objective: to describe for the first time in our country the clinical, radiological and immunological features from patients with ABPA. Patients and methods: outpatients with Asthma and ABPA who were diagnosed between 2007 and 2009, in a General Hospital and a Medical Center (Lima-Peru). This is an observational and case series study. Results: we found 6 patients who were diagnosed with ABPA, 4 females, aged between 7 y 45 years old and 5 of them in stage III. Conclusions: we found the presence of ABPA in our environment and 100 per cent of the cases found were diagnosed in advanced stages of the disease.
Assuntos
Humanos , Masculino , Feminino , Criança , Adolescente , Adulto , Pessoa de Meia-Idade , Asma , Aspergillus fumigatus , Aspergilose Broncopulmonar Alérgica , Epidemiologia Descritiva , Estudos Observacionais como Assunto , PeruRESUMO
La enfermedad pulmonar obstructiva crónica (EPOC), es una causa importante de muerte en países desarrollados (ocupa el cuarto lugar en EUA). Se ha determinado que es tan o más frecuente en los países en desarrollo, es causa de muchas hospitalizaciones y consultas por exacerbación aguda de la enfermedad (EABC). La definición de Anthonisen es la más usada y aceptada, pues señala la presencia de uno o más de los siguientes criterios: incremento en el volumen de la expectoración, cambio de color (purulencia) en el esputo y Empeoramiento de la disnea. El paciente con EPOC puede presentar de una a tres exacerbaciones agudas por año. El número de EABC es un marcador importante de severidad de la condición, pues determina la calidad de vida y mortalidad del paciente. Del 3 a 16% requiere hospitalizarse (más en casos severos). La mortalidad hospitalaria puede llegar a 10% en casos de EPOC severos y mayor si el paciente ingresa a una Unidad de Cuidado Intensivo. La etiología de la EABC es mayoritariamente infecciosa, (hasta el 80%), otras condiciones pueden explicarla, como la embolia pulmonar, neumotórax, insuficiencia cardiaca, fracturas en la caja torácica e infecciones no pulmonares, las cuales se consideran como "gatillos" y pueden coexistir más de uno por vez. A diferencia de la crisis asmática es importante que se realice una radiografía de tórax y una gasometría arterial, en todos los pacientes que acuden a la emergencia. Hasta el 20% de pacientes pueden presentar elevación del PCO2. al administrarles oxígeno, se recomienda usar de preferencia una máscara de venturi con la concentración necesaria para llevar la saturación de hemoglobina alrededor de 90% (86-92%). El uso de un broncodilatador es la elección en estos casos. Lo ideal es administrar un beta agonista de corta acción o un anticolinérgico, y si el paciente no mejora se pueden combinar. La elección...
Chronic obstructive lung disease (COPD) is an important cause of death in industrialized countries (it is the 4th cause of death in the U.S.). This condition is also prevalent in developing countries, in some its frequency may be higher, and it is an important cause of hospitalizations and consultations because of acute exacerbations. The Anthonisen definition is the most widely and accepted instrument for diagnosing COPD exacerbations, pointing out at the presence of one or more of the following: increased sputum volume, change of color of the sputum, and worsening dyspnea. Patients with COPD may develop one to three acute exacerbation episodes per year. The number of these episodes is an important marker for the severity of COPD, since it determines quality of life and the mortality risk. Three to sixteen per cent of affected patients may require hospitalization (this rate may be higher in more severe cases). In-hospital mortality may reach 10% in severe COPD cases, and it becomes increased if the patient is admitted to an intensive care unit. The etiology of acute exacerbations of COPD is mainly because of infections (up to 80%), but other conditions may also account for such exacerbations, such as pulmonary embolism, pneumothorax, heart failure, thoracic trauma (including rib fracture), and extrapulmonary infections, being considered as triggering factors, and they may also coexist. Differently from asthma crisis, it is important to have a chest X-ray film taken and arterial blood gases determinations in every patient presenting to the emergency department with an acute exacerbation of COPD. Up to 20% of patients may present with elevated PCO2. When administering oxygen, it is preferable to use a Venturi mask with an oxygen concentration able to maintain hemoglobin saturation around 90% (86-92%)...