Síntesis y funcionalización de ligandos poliméricos para su empleo en la fabricación, estabilización y autoorganización de sistemas de nanopartículas

En estos los últimos años el diseño y preparación de nuevos materiales como las nanopartículas, basados en la manipulación y estudio de la materia al nivel de la nanoescala ha experimentado un importante desarrollo, como consecuencia de las interesantes propiedades que estos materiales nanoestructurados pueden presentar. Entre los diferentes tipos de nanopartículas estudiadas, las de oro has suscitado un importante interés debido su capacidad de biocompatibilización e interesantes propiedades de tipo óptico, que cuentan con una amplia variedad de aplicaciones y que a su vez resultan fuertemente dependientes de parámetros como el tamaño, la forma o la dispersidad que las nanopartículas presenten. En relación a este hecho, es muy importante el control, fundamentalmente sintético, que se pueda ejercer sobre la morfología y la estabilidad de este tipo de nanomateriales de cara a los potenciales usos de los mismos. Con el objetivo de preparar dispersiones estables de nanopartículas de oro con control sobre el tamaño y polidispersidad de los coloides, diferentes tipos de ligandos poliméricos fueron preparados para su empleo como agentes protectores y estabilizantes en la síntesis de estas nanopartículas. Además del control sobre la polimerización de los ligandos, lo que ha permitido obtener cadenas poliméricas de peso molecular predeterminado y bajos índices de polidispersidad, la funcionalización controlada con grupos tiol, llevada a cabo a posteriori, ha resultado de fundamental importancia para el uso de este tipo de ligandos como agentes estabilizadores de las nanopartículas, debido a la alta afinidad que los grupos funcionales tiol muestra por la superficie coloidal del oro. Diferentes sistemas coloidales han sido estudiados en función del peso molecular, tipo de funcionalidad y composición molar en el sistema de los ligandos poliméricos empleados. Finalmente, se ha estudiado el uso de matrices de copolímero de bloque con el objetivo de preparar sistemas de nanopartículas autoorganizados a escala nanométrica. Mediante un procesado de annealing térmico se ha tratado de inducir la localización preferencial de las nanopartículas estabilizadas con los ligandos poliméricos en uno de los dominios copoliméricos de la matriz. Los diferentes aspectos relacionados con la localización dirigida del sistema coloidal además de la evolución de la morfología de la matriz copolimérica han sido estudiados

Neurometabolic and Electrophysiological Changes During Cortical Spreading Depolarization: Multimodal Approach Based on a Lactate-Glucose Dual Microbiosensor Arrays

Spreading depolarization (SD) is a slow propagating wave of strong depolarization of neural cells, implicated in several neuropathological conditions. The breakdown of brain homeostasis promotes significant hemodynamic and metabolic alterations, which impacts on neuronal function. In this work we aimed to develop an innovative multimodal approach, encompassing metabolic, electric and hemodynamic measurements, tailored but not limited to study SD. This was based on a novel dual-biosensor based on microelectrode arrays designed to simultaneously monitor lactate and glucose fluctuations and ongoing neuronal activity with high spatial and temporal resolution. In vitroevaluation of dual lactate-glucose microbiosensor revealed an extended linear range, high sensitivity and selectivity, fast response time and low oxygen-, temperature- and pH- dependencies. In anesthetized rats, we measured with the same array a significant drop in glucose concentration matched to a rise in lactate and concurrently with pronounced changes in the spectral profile of LFP-related currents during episodes of mechanically-evoked SD. This occurred along with the stereotypical hemodynamic response of the SD wave. Overall, this multimodal approach successfully demonstrates the capability to monitor metabolic alterations and ongoing electrical activity, thus contributing to a better understanding of the metabolic changes occurring in the brain following SD

Electrochemical Evaluation of a Multi-Site Clinical Depth Recording Electrode for Monitoring Cerebral Tissue Oxygen

The intracranial measurement of local cerebral tissue oxygen levels—PbtO2—has become a useful tool for the critical care unit to investigate severe trauma and ischemia injury in patients. Our preliminary work in animal models supports the hypothesis that multi-site depth electrode recording of PbtO2 may give surgeons and critical care providers needed information about brain viability and the capacity for better recovery. Here, we present a surface morphology characterization and an electrochemical evaluation of the analytical properties toward oxygen detection of an FDA-approved, commercially available, clinical grade depth recording electrode comprising 12 Pt recording contacts. We found that the surface of the recording sites is composed of a thin film of smooth Pt and that the electrochemical behavior evaluated by cyclic voltammetry in acidic and neutral electrolyte is typical of polycrystalline Pt surface. The smoothness of the Pt surface was further corroborated by determination of the electrochemical active surface, confirming a roughness factor of 0.9. At an optimal working potential of −0.6 V vs. Ag/AgCl, the sensor displayed suitable values of sensitivity and limit of detection for in vivo PbtO2 measurements. Based on the reported catalytical properties of Pt toward the electroreduction reaction of O2, we propose that these probes could be repurposed for multisite monitoring of PbtO2 in vivo in the human brain

In vitro viability of genipap pollen grains in different culture media

O objetivo deste trabalho foi avaliar a viabilidade in vitro do grão de pólen de jenipapeiro (Genipa americana) à temperatura ambiente, em diferentes meios de cultura. O delineamento experimental foi inteiramente casualizado em arranjo fatorial 3x11 (meios de cultura x tempos de incubação), com quatro repetições. O número de grãos de pólen germinados foi analisado em intervalos de 24 horas até 288 horas após incubação em temperatura ambiente. O meio com 100 mg ha-1 de H3BO3, 80 g L-1 de sacarose e 1,0 L-1 de ágar resulta em alta à média percentagem de germinação in vitro, sendo o mais adequado para estudos da viabilidade in vitro de grãos de pólen de jenipapeiro.The objective of this work was to evaluate the viability of genipap (Genipa americana) pollen grain at room temperature in different culture media. The experimental design was completely randomized in a 3x11 factorial arrangement (culture media x incubation times) with four replicates. The number of germinated pollen grains was analyzed at 24-hour intervals up to 288 hours after incubation at room temperature. The culture medium with 100 mg L-1 H3BO3, 80 g L-1 sucrose, and 1.0 g L-1 agar results in a higher to intermediate germination percentage, being the most suitable for studies on the in vitro viability of genipap pollen grains

Rutinitas Wartawan dalam Memproduksi Berita

The rapid development of information and communication technology brings relevant changes in several areas of human life. No exception with the field of journalism. Developments that influence the existence of the media force conventional media to provide new policies that are more efficient and effective for society. One of them is by making an online version of the news portal. Increasingly intense media competition requires online journalistic media workers to work fast from searching to working on news that is a routine for journalists. The purpose of this study was to find out the routines of ANTARA News NTT online media reporters in producing news and to find out the meaning of routines by ANTARA News NTT online media reporters in producing news. The theory used in research is the theory of new media / new media. The method in this study uses ethnographic media methods. Data were collected through in-depth interview techniques, participatory observation, and documentation. While the data analysis uses Cresswell's analysis model, and the data validity technique uses triangulation. The results showed that the routine of ANTARA News's online media reporter NTT in producing news consisted of five stages, including preparing the agenda for coverage, coverage, news script writing, editing by the editor, and dissemination to the general public. ANTARA News NTT online media reporter interpreted his routine in producing news, including journalist rituals, part of a journalist's life, and the demands of the profession

Caracterización clínica y epidemiológica de pacientes con cáncer laríngeo

Introducción: La laringe es uno de los órganos más importantes de la vía respiratoria y la digestiva superior. Existen factores de riesgo para la producción del cáncer laríngeo, que aparece por encima de los 40 años y es frecuente en los hombres. Objetivo: Caracterizar a pacientes con carcinoma epidermoide de laringe, desde el punto de vista clínico y epidemiológico. Métodos: Se realizó un estudio descriptivo, transversal, de todos los pacientes con diagnóstico de cáncer laríngeo atendidos en el Hospital Militar Central "Dr. Carlos J. Finlay", desde enero de 2010 a enero de 2015; se revisaron las historias clínicas de los pacientes con diagnóstico histológico de carcinoma epidermoide de laringe; se tuvo en cuenta la edad, sexo, color de la piel, factores de riesgo, antecedentes personales o familiares de enfermedades oncológicas, manifestaciones clínicas y examen físico. Resultados: Predominaron pacientes mayores de 60 años, donde la presencia de leucoplasia y laringitis alcanzó un 15,82 %, fuman y beben el 60 % de ellos y predominó la afección glótica con 79,09 %. Conclusiones: El sexo masculino tuvo mayor incidencia, el tabaquismo y el consumo de bebidas alcohólicas predominó, al igual que la localización en la glotis y el grado de diferenciación fue moderado y bien diferenciado

Cambuí (Myrciaria floribunda (West ex Willd.) O. Berg): A potential nutritional supplement for inhibition of COVID-19 infections / Cambuí (Myrciaria floribunda (West ex Willd.) O. Berg): Um potencial suplemento nutricional para a inibição de infecções por COVID-19

In the present study, we suggest that the Myrciaria floribunda (West ex Willd.) O. Berg fruit (cambuí) is a natural source of potential molecules against COVID-19. Extracts from orange and purple cambuí were obtained by using pressurized hot water extraction (PHWE). Extraction overall yield was 39.66 ± 1.62% and 33.00 ± 8.44% for the extracts of purple and orange cambuí, respectively. All analyzed extracts showed high total phenolic contents, especially those of purple fruits (3870.37 ± 353.09 mg GAE/100g). The total flavonoid content was 693.16 ± 180.09 and 770.08 ± 103.62 mg RE/100g for purple and orange fruit extracts, respectively. The secondary metabolite profile exhibited ellagic acid, ellagitannins, and derivatives of caffeic acid and ellagic acid. PHWE showed a good alternative for molecules separation from cambuí with promising potential for further in vitro and in vivo evaluation against Covid-19 infections

Callogénesis y caracterización morfohistológica de Hancornia speciosa Gomes

Hancornia speciosa Gomes belongs to the family Apocynaceae and is distributed across different regions of Brazil. The objective of this study was to evaluate callus induction and histodifferentiation in five mangaba accessions under different in vitro culture conditions. Five acessions from the Active Germplasm Bank of Mangaba (Embrapa, Brazil) were evaluated. In vitro-germinated plant seedlings were used for the excision of different explants (internode and node segments, and foliar section). These segments were inoculated in a culture medium containing different concentrations of 6-Benzylaminopurine (BA) and 2,4-Dichlorophenoxyacetic acid (2,4-D). There was a significant effect of accessions, treatments, and time on the callus mass (g). There was no callus induction in the absence of regulators. After 60 days of in vitro culture, all treatments exhibited a linear positive cellular growth. The highest callus mass was observed in the BI accession, in the presence of 22.62 µM 2,4-D and 11.10 µM BA.Hancornia speciosa Gomes pertenece a la familia Apocynaceae, distribuida en diferentes regiones de Brasil. El objetivo de este trabajo fue evaluar la callogénesis y la histodiferenciación en cinco accesiones de mangaba bajo diferentes condiciones de cultivo in vitro. Se evaluaron cinco accesiones del Banco de Germoplasma Activo de Mangaba (Embrapa, Brasil). Las plántulas germinadas in vitro se utilizaron para la escisión de explantes (segmentos nodales e internodales y secciones foliares). Estos segmentos fueron inoculados en un medio de cultivo que contenía diferentes concentraciones de 6-benzilaminopurina (BA) y ácido 2,4-diclorofenoxiacético (2,4-D). Hubo un efecto significativo de las accesiones, los tratamientos y el tiempo del cultivo en la masa de los callos. No hubo inducción de callos en ausencia de reguladores. A los 60 días de cultivo in vitro, los otros tratamientos presentaron un crecimiento celular linear positivo. La mayor masa de callo se observó en la accesión BI, en presencia de 22,62 μM 2,4-D y 11,10 μM BA