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1.
Med Intensiva ; 47(5): 257-266, 2023 May.
Artículo en Español | MEDLINE | ID: mdl-36506823

RESUMEN

Objective: To describe the sequelae one month after hospital discharge in patients who required admission to intensive care for severe COVID-19 pneumonia and to analyze the differences between those who received therapy exclusively with high-flow oxygen therapy compared to those who required invasive mechanical ventilation. Design: Cohort, prospective and observational study. Setting: Post-intensive care multidisciplinary program. Patients or participants: Patients who survived admission to the intensive care unit (ICU) for severe COVID-19 pneumonia from April 2020 to October 2021. Interventions: Inclusion in the post-ICU multidisciplinary program. Main variables of interest: Motor, sensory, psychological/psychiatric, respiratory and nutritional sequelae after hospital admission. Results: One hundred and four patients were included. 48 patients received high-flow nasal oxygen therapy (ONAF) and 56 invasive mechanical ventilation (IMV). The main sequelae found were distal neuropathy (33.9% IMV vs. 10.4% ONAF); brachial plexopathy (10.7% IMV vs. 0% ONAF); decrease in grip strength: right hand 20.67 kg (± 8.27) in VMI vs. 31.8 kg (± 11.59) in ONAF and left hand 19.39 kg (± 8.45) in VMI vs. 30.26 kg (± 12.74) in ONAF; and limited muscle balance in the lower limbs (28.6% VMI vs. 8.6% ONAF). The differences observed between both groups did not reach statistical significance in the multivariable study. Conclusions: The results obtained after the multivariate study suggest that there are no differences in the perceived physical sequelae one month after hospital discharge depending on the respiratory therapy used, whether it was high-flow nasal oxygen therapy or prolonged mechanical ventilation, although more studies are needed to be able to draw conclusions.

2.
Sensors (Basel) ; 19(24)2019 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-31847169

RESUMEN

A sensing configuration for the real-time monitoring, detection, and quantification of dissolved carbon dioxide (dCO2) was developed for aquaculture and other applications in freshwater and saline water. A chemical sensing membrane, based on a colorimetric indicator, is combined with multimode optical fiber and a dual wavelength light-emitting diode (LED) to measure the dCO2-induced absorbance changes in a self-referenced ratiometric scheme. The detection and processing were achieved with an embeded solution having a mini spectrometer and microcontroller. For optrode calibration, chemical standard solutions using sodium carbonate in acid media were used. Preliminary results in a laboratory environment showed sensitivity for small added amounts of CO2 (0.25 mg·L-1). Accuracy and response time were not affected by the type of solution, while precision was affected by salinity. Calibration in freshwater showed a limit of detection (LOD) and a limit of quantification (LOQ) of 1.23 and 1.87 mg·L-1, respectively. Results in saline water (2.5%) showed a LOD and LOQ of 1.05 and 1.16 mg·L-1, respectively. Generally, performance was improved when moving from fresh to saline water. Studies on the dynamics of dissolved CO2 in a recirculating shallow raceway system (SRS+RAS) prototype showed higher precision than the tested commercial sensor. The new sensor is a compact and robust device, and unlike other sensors used in aquaculture, stirring is not required for correct and fast detection. Tests performed showed that this new sensor has a fast accurate detection as well as a strong potential for assessing dCO2 dynamics in aquaculture applications.


Asunto(s)
Acuicultura/métodos , Dióxido de Carbono/análisis , Aguas Salinas/análisis , Colorimetría , Monitoreo del Ambiente/métodos , Fibras Ópticas
3.
Public Health ; 143: 17-24, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28159023

RESUMEN

OBJECTIVES: Using a national representative sample of adolescents with unemployed parents, this study examined which factors (sociodemographic and of satisfaction with family life and peers) are related to the negative effect of parents' unemployment on emotional well-being. STUDY DESIGN: Cross-sectional survey study. METHODS: Data on adolescents (14.1 ± 1.7 years old), with at least one parent unemployed (n = 1311, 53.2% girls), was provided by the Portuguese Health Behaviour in School-aged Children study. Descriptive statistics and logistic regression analyses were performed. RESULTS: A high proportion of adolescents reported being emotionally affected by father's unemployment but not by their mother's. Older boys and older girls were more likely to report that their same-gender parent's unemployment situation (sons-fathers and daughters-mothers) has had a negative effect on their well-being. Girls from low socio-economic status and with poor family satisfaction were more likely to report negative emotional well-being related to parental unemployment. CONCLUSIONS: This study presents evidence on factors that can shape adolescents' emotional well-being related to parents' unemployment situation. Given the recessionary context and high unemployment rates, these insights are valuable to assist the design of an action to improve the levels of well-being of Portuguese adolescents from unemployed families.


Asunto(s)
Recesión Económica , Trastornos Mentales/epidemiología , Padres , Desempleo/estadística & datos numéricos , Adolescente , Estudios Transversales , Familia/psicología , Femenino , Humanos , Masculino , Grupo Paritario , Satisfacción Personal , Portugal/epidemiología , Factores de Riesgo , Clase Social
4.
Psychol Med ; 46(2): 327-43, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26511595

RESUMEN

BACKGROUND: Considerable research has documented that exposure to traumatic events has negative effects on physical and mental health. Much less research has examined the predictors of traumatic event exposure. Increased understanding of risk factors for exposure to traumatic events could be of considerable value in targeting preventive interventions and anticipating service needs. METHOD: General population surveys in 24 countries with a combined sample of 68 894 adult respondents across six continents assessed exposure to 29 traumatic event types. Differences in prevalence were examined with cross-tabulations. Exploratory factor analysis was conducted to determine whether traumatic event types clustered into interpretable factors. Survival analysis was carried out to examine associations of sociodemographic characteristics and prior traumatic events with subsequent exposure. RESULTS: Over 70% of respondents reported a traumatic event; 30.5% were exposed to four or more. Five types - witnessing death or serious injury, the unexpected death of a loved one, being mugged, being in a life-threatening automobile accident, and experiencing a life-threatening illness or injury - accounted for over half of all exposures. Exposure varied by country, sociodemographics and history of prior traumatic events. Being married was the most consistent protective factor. Exposure to interpersonal violence had the strongest associations with subsequent traumatic events. CONCLUSIONS: Given the near ubiquity of exposure, limited resources may best be dedicated to those that are more likely to be further exposed such as victims of interpersonal violence. Identifying mechanisms that account for the associations of prior interpersonal violence with subsequent trauma is critical to develop interventions to prevent revictimization.


Asunto(s)
Accidentes de Tránsito/estadística & datos numéricos , Víctimas de Crimen/estadística & datos numéricos , Enfermedad Crítica/epidemiología , Estado Civil/estadística & datos numéricos , Trauma Psicológico/epidemiología , Trastornos por Estrés Postraumático/epidemiología , Adulto , Anciano , Análisis Factorial , Femenino , Humanos , Cooperación Internacional , Modelos Logísticos , Masculino , Persona de Mediana Edad , Prevalencia , Factores Protectores , Factores de Riesgo , Encuestas y Cuestionarios , Adulto Joven
5.
Psychol Med ; 46(14): 2955-2970, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27484622

RESUMEN

BACKGROUND: Although mental disorders are significant predictors of educational attainment throughout the entire educational career, most research on mental disorders among students has focused on the primary and secondary school years. METHOD: The World Health Organization World Mental Health Surveys were used to examine the associations of mental disorders with college entry and attrition by comparing college students (n = 1572) and non-students in the same age range (18-22 years; n = 4178), including non-students who recently left college without graduating (n = 702) based on surveys in 21 countries (four low/lower-middle income, five upper-middle-income, one lower-middle or upper-middle at the times of two different surveys, and 11 high income). Lifetime and 12-month prevalence and age-of-onset of DSM-IV anxiety, mood, behavioral and substance disorders were assessed with the Composite International Diagnostic Interview (CIDI). RESULTS: One-fifth (20.3%) of college students had 12-month DSM-IV/CIDI disorders; 83.1% of these cases had pre-matriculation onsets. Disorders with pre-matriculation onsets were more important than those with post-matriculation onsets in predicting subsequent college attrition, with substance disorders and, among women, major depression the most important such disorders. Only 16.4% of students with 12-month disorders received any 12-month healthcare treatment for their mental disorders. CONCLUSIONS: Mental disorders are common among college students, have onsets that mostly occur prior to college entry, in the case of pre-matriculation disorders are associated with college attrition, and are typically untreated. Detection and effective treatment of these disorders early in the college career might reduce attrition and improve educational and psychosocial functioning.


Asunto(s)
Salud Global/estadística & datos numéricos , Trastornos Mentales/epidemiología , Salud Mental/estadística & datos numéricos , Estudiantes/estadística & datos numéricos , Universidades/estadística & datos numéricos , Organización Mundial de la Salud , Adolescente , Adulto , Femenino , Encuestas Epidemiológicas , Humanos , Masculino , Adulto Joven
6.
Child Psychiatry Hum Dev ; 47(5): 751-8, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-26646144

RESUMEN

We investigated, in a sample of 112 unemployed parents of adolescents aged 10-19 years, the links between parental distress and change in youth emotional problems related to parental unemployment, and the moderation roles of parent-youth relationship and financial deprivation. Data were analyzed using descriptive statistics and correlations. Further, simple moderation, additive moderation, and moderated moderation models of regression were performed to analyze the effects of parental distress, parent-youth relationship and financial deprivation in predicting change in youth emotional problems related to parental unemployment. Results show that parental distress moderated by parent-youth relationship predicted levels of change in youth emotional problems related to parental unemployment. This study provides evidence that during job loss, parental distress is linked to youth emotional well-being and that parent-youth relationships play an important moderation role. This raises the importance of further researching parental distress impacts on youth well-being, especially during periods of high unemployment rates.


Asunto(s)
Protección a la Infancia , Padres/psicología , Estrés Psicológico , Desempleo/psicología , Adolescente , Adulto , Niño , Protección a la Infancia/economía , Protección a la Infancia/psicología , Emociones , Femenino , Humanos , Masculino , Relaciones Padres-Hijo , Estrés Psicológico/etiología , Estrés Psicológico/prevención & control , Estrés Psicológico/psicología
7.
Diabet Med ; 32(11): 1520-6, 2015 11.
Artículo en Inglés | MEDLINE | ID: mdl-26118472

RESUMEN

AIMS: Hypoglycaemia is a serious medical emergency. The need for emergency medical service care and the costs of hypoglycaemic emergencies are not completely known. METHODS: This was a retrospective observational study using Public Company for Health Emergencies (EPES) data for hypoglycaemia in 2012. The EPES provides emergency medical services to the entire population of Andalusia, Spain (8.5 million people). Data on event type, onsite treatments, emergency room visits or hospitalization were collected. Medical costs were estimated using the public rates for healthcare services. RESULTS: From a total of 1 137 738 emergency calls that requested medical assistance, 8683 had a primary diagnosis of hypoglycaemia (10.34 per 10 000 person-years). The incidence of severe hypoglycaemic episodes requiring emergency treatment in the estimated population with diabetes was 80 episodes per 10 000 person-years. A total of 7479 episodes (86%) required an emergency team to visit the patient's residence. The majority of cases (64%) were addressed in the residence, although 1784 (21%) cases were transferred to hospital. A total of 5564 events (65%) involved patients aged > 65 years. Overall mortality was 0.32% (28 cases). The total annual cost of attending a hypoglycaemic episode was €6 093 507, leading to an estimated mean direct cost per episode of €702 ± 565. Episodes that required hospital treatment accounted for 49% of the total costs. CONCLUSIONS: Hypoglycaemia is a common medical emergency that is associated with high emergency medical service utilization, resulting in a significant economic impact on the health system.


Asunto(s)
Complicaciones de la Diabetes/terapia , Costos Directos de Servicios , Servicios Médicos de Urgencia , Hipoglucemia/terapia , Adolescente , Adulto , Factores de Edad , Anciano , Niño , Complicaciones de la Diabetes/economía , Complicaciones de la Diabetes/epidemiología , Complicaciones de la Diabetes/fisiopatología , Servicios Médicos de Urgencia/economía , Servicio de Urgencia en Hospital/economía , Femenino , Hospitalización , Humanos , Hipoglucemia/economía , Hipoglucemia/epidemiología , Hipoglucemia/fisiopatología , Incidencia , Lactante , Masculino , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , España/epidemiología
8.
Appl Opt ; 54(35): 10342-8, 2015 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-26836856

RESUMEN

A study of a sensor for hydrogen (H2) detection based on fiber Bragg gratings coated with palladium (Pd) with self-temperature compensation is presented. The cladding around the gratings was reduced down to 50 µm diameter by a chemical etching process. One of the gratings was left uncoated, and the other was coated with 150 nm of Pd. It was observed that palladium hydride has unstable behavior in environments with high humidity level. A simple solution to overcome this problem based on a Teflon tape is presented. The sensing device studied was able to respond to H2 concentrations in the range 0%-1% v/v at room temperature and atmospheric pressure, achieving sensitivities larger than 20 pm/% v/v. Considering H2 concentrations in nitrogen up to 1%, the performance of the sensing head was characterized for different thicknesses of Pd coating ranging from 50 to 200 nm.

9.
Bioprocess Biosyst Eng ; 38(10): 1889-902, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26093658

RESUMEN

ß-Glucosidases are important enzymes with significant prospects in the industrial biotechnology, including their use in biomass hydrolysis for bioethanol production. In this study, the use of canola meal as carbon source for ß-glucosidase production by a Trichoderma viride strain in submerged fermentation was evaluated by applying central composite design and response surface methodology to optimize the production process. This statistical approach was also used to improve the passion fruit peel hydrolysis by T. viride crude extract. The model developed 3.6-fold increased ß-glucosidase activity. The culture conditions that resulted in the highest ß-glucosidase levels were a substrate concentration of 2.9 %, pH of medium 4.2 and cultivation time of 206 h. The ß-glucosidases produced under optimal conditions showed attractive properties for industrial applications, such as activity at high temperatures and stability at 55 °C and over a wide pH range. In addition, the enzymatic hydrolysis of passion fruit peel by T. viride crude extract was very promising, resulting in glucose yields of 66.4 %. This study, therefore, presents canola meal as an inexpensive and attractive substrate for the production of microbial ß-glucosidases.


Asunto(s)
Brassica rapa/microbiología , Residuos Industriales/prevención & control , Modelos Biológicos , Extractos Vegetales/metabolismo , Trichoderma/enzimología , beta-Glucosidasa/biosíntesis , Brassica rapa/química , Carbohidratos , Simulación por Computador , Activación Enzimática , Modelos Estadísticos , Especificidad por Sustrato , beta-Glucosidasa/aislamiento & purificación
10.
Psychol Med ; 44(4): 707-22, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23721650

RESUMEN

BACKGROUND: The World Mental Health Survey Initiative (WMHSI) has advanced our understanding of mental disorders by providing data suitable for analysis across many countries. However, these data have not yet been fully explored from a cross-national lifespan perspective. In particular, there is a shortage of research on the relationship between mood and anxiety disorders and age across countries. In this study we used multigroup methods to model the distribution of 12-month DSM-IV/CIDI mood and anxiety disorders across the adult lifespan in relation to determinants of mental health in 10 European Union (EU) countries. METHOD: Logistic regression was used to model the odds of any mood or any anxiety disorder as a function of age, gender, marital status, urbanicity and employment using a multigroup approach (n = 35500). This allowed for the testing of specific lifespan hypotheses across participating countries. RESULTS: No simple geographical pattern exists with which to describe the relationship between 12-month prevalence of mood and anxiety disorders and age. Of the adults sampled, very few aged ≥ 80 years met DSM-IV diagnostic criteria for these disorders. The associations between these disorders and key sociodemographic variables were relatively homogeneous across countries after adjusting for age. CONCLUSIONS: Further research is required to confirm that there are indeed stages in the lifespan where the reported prevalence of mental disorders is low, such as among younger adults in the East and older adults in the West. This project illustrates the difficulties in conducting research among different age groups simultaneously.


Asunto(s)
Trastornos de Ansiedad/epidemiología , Salud Global , Trastornos del Humor/epidemiología , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Europa (Continente)/epidemiología , Femenino , Salud Global/estadística & datos numéricos , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Prevalencia , Factores de Tiempo , Adulto Joven
11.
Psychol Med ; 43(4): 865-79, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22877824

RESUMEN

BACKGROUND: Current trends in population aging affect both recipients and providers of informal family caregiving, as the pool of family caregivers is shrinking while demand is increasing. Epidemiological research has not yet examined the implications of these trends for burdens experienced by aging family caregivers. Method Cross-sectional community surveys in 20 countries asked 13 892 respondents aged 50+ years about the objective (time, financial) and subjective (distress, embarrassment) burdens they experience in providing care to first-degree relatives with 12 broadly defined serious physical and mental conditions. Differential burden was examined by country income category, kinship status and type of condition. RESULTS: Among the 26.9-42.5% respondents in high-, upper-middle-, and low-/lower-middle-income countries reporting serious relative health conditions, 35.7-42.5% reported burden. Of those, 25.2-29.0% spent time and 13.5-19.4% money, while 24.4-30.6% felt distress and 6.4-21.7% embarrassment. Mean caregiving hours per week in those giving any time were 16.6-23.6 (169.9-205.8 h/week per 100 people aged 50+ years). Burden in low-/lower-middle-income countries was 2- to 3-fold higher than in higher-income countries, with any financial burden averaging 14.3% of median family income in high-, 17.7% in upper-middle-, and 39.8% in low-/lower-middle-income countries. Higher burden was reported by women than men and for conditions of spouses and children than parents or siblings. CONCLUSIONS: Uncompensated family caregiving is an important societal asset that offsets rising formal healthcare costs. However, the substantial burdens experienced by aging caregivers across multiple family health conditions and geographic regions threaten the continued integrity of their caregiving capacity. Initiatives supporting older family caregivers are consequently needed, especially in low-/lower-middle-income countries.


Asunto(s)
Cuidadores/estadística & datos numéricos , Costo de Enfermedad , Comparación Transcultural , Salud de la Familia/estadística & datos numéricos , Atención Domiciliaria de Salud/estadística & datos numéricos , Dinámica Poblacional/tendencias , Adulto , Factores de Edad , Cuidadores/economía , Cuidadores/tendencias , Niño , Enfermedad Crónica/economía , Enfermedad Crónica/enfermería , Métodos Epidemiológicos , Familia , Salud de la Familia/economía , Femenino , Salud Global , Atención Domiciliaria de Salud/economía , Atención Domiciliaria de Salud/tendencias , Humanos , Masculino , Trastornos Mentales/economía , Trastornos Mentales/enfermería , Persona de Mediana Edad , Factores Socioeconómicos , Factores de Tiempo , Organización Mundial de la Salud
12.
Nanotechnology ; 24(49): 495201, 2013 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-24231442

RESUMEN

Graphane, hydrogenated graphene, can be patterned into electronic devices by selectively removing hydrogen atoms. The most simple of such devices is the so-called nanoroad, analogous to the graphene nanoribbon, where confinement-and the opening of a gap-is obtained without the need for breaking the carbon bonds. In this work we address the electronic transport properties of such systems considering different hydrogen impurities within the conduction channel. We show, using a combination of density functional theory and non-equilibrium Green's functions, that hydrogen leads to significant changes in the transport properties and in some cases to current polarization.

13.
Genet Mol Res ; 12(4): 6915-22, 2013 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-24391039

RESUMEN

Pollen substitute diets are a valuable resource for maintaining strong and health honey bee colonies. Specific diets may be useful in one region or country and inadequate or economically unviable in others. We compared two artificial protein diets that had been formulated from locally-available ingredients in Brazil with bee bread and a non-protein sucrose diet. Groups of 100 newly-emerged, adult workers of Africanized honey bees in Brazil and European honey bees in the USA were confined in small cages and fed on one of four diets for seven days. The artificial diets included a high protein diet made of soy milk powder and albumin, and a lower protein level diet consisting of soy milk powder, brewer's yeast and rice bran. The initial protein levels in newly emerged bees were approximately 18-21 µg/µL hemolymph. After feeding on the diets for seven days, the protein levels in the hemolymph were similar among the protein diet groups (~37-49 µg/µL after seven days), although Africanized bees acquired higher protein levels, increasing 145 and 100% on diets D1 and D2, respectively, versus 83 and 60% in the European bees. All the protein diets resulted in significantly higher levels of protein than sucrose solution alone. In the field, the two pollen substitute diets were tested during periods of low pollen availability in the field in two regions of Brazil. Food consumption, population development, colony weight, and honey production were evaluated to determine the impact of the diets on colony strength parameters. The colonies fed artificial diets had a significant improvement in all parameters, while control colonies dwindled during the dearth period. We conclude that these two artificial protein diets have good potential as pollen substitutes during dearth periods and that Africanized bees more efficiently utilize artificial protein diets than do European honey bees.


Asunto(s)
Abejas , Dieta/veterinaria , Proteínas en la Dieta/administración & dosificación , Polen , Própolis/administración & dosificación , Animales , Brasil , Alimentos , Hemolinfa , Alimentos de Soja
14.
Med Intensiva (Engl Ed) ; 47(5): 257-266, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36621347

RESUMEN

OBJECTIVE: To describe the sequelae one month after hospital discharge in patients who required admission to Intensive Care for severe COVID 19 pneumonia and to analyze the differences between those who received therapy exclusively with high-flow oxygen therapy compared to those who required invasive mechanical ventilation. DESIGN: Cohort, prospective and observational study. SETTING: Post-intensive care multidisciplinary program. PATIENTS OR PARTICIPANTS: Patients who survived admission to the intensive care unit (ICU) for severe COVID 19 pneumonia from April 2020 to October 2021. INTERVENTIONS: Inclusion in the post-ICU multidisciplinary program. MAIN VARIABLES OF INTEREST: Motor, sensory, psychological/psychiatric, respiratory and nutritional sequelae after hospital admission. RESULTS: 104 patients were included. 48 patients received high-flow nasal oxygen therapy (ONAF) and 56 invasive mechanical ventilation (IMV). The main sequelae found were distal neuropathy (33.9% IMV vs 10.4% ONAF); brachial plexopathy (10.7% IMV vs 0% ONAF); decrease in grip strength: right hand 20.67kg (±8.27) in VMI vs 31.8kg (±11.59) in ONAF and left hand 19.39kg (±8.45) in VMI vs 30.26kg (±12.74) in ONAF; and limited muscle balance in the lower limbs (28.6% VMI vs 8.6% ONAF). The differences observed between both groups did not reach statistical significance in the multivariable study. CONCLUSIONS: The results obtained after the multivariate study suggest that there are no differences in the perceived physical sequelae one month after hospital discharge depending on the respiratory therapy used, whether it was high-flow nasal oxygen therapy or prolonged mechanical ventilation, although more studies are needed to be able to draw conclusions.


Asunto(s)
COVID-19 , Humanos , COVID-19/complicaciones , COVID-19/terapia , Alta del Paciente , SARS-CoV-2 , Estudios Prospectivos , Respiración Artificial , Cuidados Críticos , Oxígeno , Hospitales
15.
Opt Express ; 20(14): 15106-13, 2012 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-22772208

RESUMEN

Glasses containing metallic nanoparticles are promising materials for technological applications in optics and photonics. Although several methods are available to generate nanoparticles in glass, only femtosecond lasers allow controlling it three-dimensionally. In this direction, the present work investigates the generation of copper nanoparticles on the surface and in the bulk of a borosilicate glass by fs-laser irradiation. We verified the formation of copper nanoparticles, after heat treatment, by UV-Vis absorption, transmission electron microscopy and electron diffraction. A preferential growth of copper nanoparticles was observed in the bottom of the irradiated region, which was attributed to self-focusing in the glass.

17.
Opt Express ; 19(18): 17220-5, 2011 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-21935085

RESUMEN

We have determined two-photon absorption and nonlinear refraction spectra of the 50BO(1.5) - (50-x)PbF(2) - xPbO glasses (with x = 25, 35, 50 cationic %) at the range of the 470 and 1550 nm. The replacement of fluor atoms by oxygen leads to an increase in the third-order susceptibility, due to the formation of non-bridging oxygens (NBO). The nonlinear index of refraction is one order of magnitude higher than the one for fused silica, and it increases almost twice for the sample with x = 50. This sample has also shown promising features for all-optical switching as well as for optical limiting.

18.
J Dent Res ; 100(10): 1118-1126, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34315311

RESUMEN

The development of biomaterials based on the combination of biopolymers with bioactive compounds to develop delivery systems capable of modulating dentin regeneration mediated by resident cells is the goal of current biology-based strategies for regenerative dentistry. In this article, the bioactive potential of a simvastatin (SV)-releasing chitosan-calcium-hydroxide (CH-Ca) scaffold was assessed. After the incorporation of SV into CH-Ca, characterization of the scaffold was performed. Dental pulp cells (DPCs) were seeded onto scaffolds for the assessment of cytocompatibility, and odontoblastic differentiation was evaluated in a microenvironment surrounded by dentin. Thereafter, the cell-free scaffold was adapted to dentin discs positioned in artificial pulp chambers in direct contact with a 3-dimensional (3D) culture of DPCs, and the system was sealed to simulate internal pressure at 20 cm/H2O. In vivo experiments with cell-free scaffolds were performed in rats' calvaria defects. Fourier-transform infrared spectroscopy spectra proved incorporation of Ca and SV into the scaffold structure. Ca and SV were released upon immersion in a neutral environment. Viable DPCs were able to spread and proliferate on the scaffold over 14 d. Odontoblastic differentiation occurred in the DPC/scaffold constructs in contact with dentin, in which SV supplementation promoted odontoblastic marker overexpression and enhanced mineralized matrix deposition. The chemoattractant potential of the CH-Ca scaffold was improved by SV, with numerous viable and dentin sialoprotein-positive cells from the 3D culture being observed on its surface. Cells at 3D culture featured increased gene expression of odontoblastic markers in contact with the SV-enriched CH-Ca scaffold. CH-Ca-SV led to intense mineralization in vivo, presenting mineralization foci inside its structure. In conclusion, the CH-Ca-SV scaffold induces differentiation of DPCs into a highly mineralizing phenotype in the presence of dentin, creating a microenvironment capable of attracting pulp cells to its surface and inducing the overexpression of odontoblastic markers in a cell-homing strategy.


Asunto(s)
Quitosano , Animales , Calcio , Diferenciación Celular , Pulpa Dental , Dentina , Odontoblastos , Ratas , Simvastatina/farmacología
19.
J Synchrotron Radiat ; 17(3): 348-51, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20400832

RESUMEN

The growth kinetics of NiO nanoparticles have been studied by in situ X-ray diffraction using two detection systems (conventional and imaging plate). NiO nanoparticles were formed by thermal decomposition after heating of an amorphous compound formed by the coprecipitation method. It was found that the detection method using an imaging plate is more efficient than the conventional detection mode for observing changes in the crystallite growth of nanocrystalline materials. Studies have been carried out to investigate the effects of the heating rates on the particles growth. The results suggest that the growth process of the particles is accelerated when the samples are treated at low heating rates. The evolution of particles size and the diffusion coefficient obtained from X-ray powder diffraction patterns are discussed in terms of the thermal conditions for the two types of detection.

20.
Br J Nutr ; 103(1): 114-22, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19747416

RESUMEN

Discordances exist in epidemiological studies regarding the association between the intake of nutrients and death and disease. We evaluated the social and health profile of persons who consumed olive oil in a prospective population cohort investigation (Pizarra study) with a 6-year follow-up. A food frequency questionnaire and a 7 d quantitative questionnaire were administered to 538 persons. The type of oil used in food preparation was determined by direct measurement of the fatty acids in samples obtained from the kitchens of the participants at baseline and after follow-up for 6 years. The fatty acid composition of the serum phospholipids was used as an endogenous marker of the type of oil consumed. Total fat intake accounted for a mean 40 % of the energy (at baseline and after follow-up). The concordance in intake of MUFA over the study period was high. The fatty acid composition of the serum phospholipids was significantly associated with the type of oil consumed and with fish intake. The concentration of polar compounds and polymers, indicative of degradation, was greater in oils from the kitchens where sunflower oil or refined olive oil was used, in oils used for deep frying and in oils that had been reused for frying five times or more. Consumption of olive oil was directly associated with educational level. Part of the discordance found in epidemiological studies between diet and health may be due to the handling of oils during food preparation. The intake of olive oil is associated with other healthy habits.


Asunto(s)
Índice de Masa Corporal , Grasas de la Dieta , Ingestión de Energía , Estado de Salud , Estilo de Vida , Aceites de Plantas , Adolescente , Adulto , Anciano , Grasas Insaturadas en la Dieta , Conducta Alimentaria , Femenino , Humanos , Masculino , Islas del Mediterráneo , Persona de Mediana Edad , Aceite de Oliva , Fosfolípidos/sangre , Estudios Prospectivos , España , Encuestas y Cuestionarios , Adulto Joven
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