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1.
Nature ; 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-39020171

RESUMEN

Giant exoplanets orbiting close to their host stars are unlikely to have formed in their present configurations1. These 'hot Jupiter' planets are instead thought to have migrated inward from beyond the ice line and several viable migration channels have been proposed, including eccentricity excitation through angular-momentum exchange with a third body followed by tidally driven orbital circularization2,3. The discovery of the extremely eccentric (e = 0.93) giant exoplanet HD 80606 b (ref. 4) provided observational evidence that hot Jupiters may have formed through this high-eccentricity tidal-migration pathway5. However, no similar hot-Jupiter progenitors have been found and simulations predict that one factor affecting the efficacy of this mechanism is exoplanet mass, as low-mass planets are more likely to be tidally disrupted during periastron passage6-8. Here we present spectroscopic and photometric observations of TIC 241249530 b, a high-mass, transiting warm Jupiter with an extreme orbital eccentricity of e = 0.94. The orbit of TIC 241249530 b is consistent with a history of eccentricity oscillations and a future tidal circularization trajectory. Our analysis of the mass and eccentricity distributions of the transiting-warm-Jupiter population further reveals a correlation between high mass and high eccentricity.

2.
CienciaUAT ; 15(2): 186-197, ene.-jun. 2021. tab, graf
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1285901

RESUMEN

Resumen Los organismos marinos poseen maravillosos colores que los hacen muy atractivos. Las características únicas de los compuestos sintetizados por especies de origen marino van más allá de su apariencia. Los pigmentos responsables de esos colores son capaces también de generar diversas actividades biológicas, como la capacidad antioxidante, la cual puede ocurrir a través de diversos mecanismos. Esto ha propiciado un aumento de su investigación, debido a su amplia aplicación en la biotecnología, farmacéutica, cosmética y alimentación de organismos vivos, expandiendo los estudios tanto in vitro como en ensayos in vivo. El objetivo de este trabajo fue compilar y describir diversos estudios recientes, enfocados en demostrar y elucidar los mecanismos de acción de los diferentes compuestos bioquímicos con actividad antioxidante, provenientes de algunos organismos marinos. Para ello, se utilizaron las bases de datos Scopus®, Web of Science™ y Microsoft Academic. Los pigmentos provenientes de organismos marinos representan una alternativa promisoria frente a los antioxidantes y aditivos sintéticos utilizados en la actualidad. El establecimiento y comprensión de los mecanismos de acción de los componentes pigmentados bioactivos, aislados de los organismos marinos, permitirá determinar con mayor precisión su posible aplicación en la industria.


Abstract Marine organisms have wonderful colors that make them very attractive. The unique characteristics of the compounds synthesized by species of marine origin go beyond their appearance. The pigments responsible for these colors are also capable of exerting biological activities, including the antioxidant capacity, which can be performed by different mechanisms. This has led to an increase in research attention due to their potential application in the pharmaceutical, cosmetics and food industries, and has expanded from in vitro studies to in vivo tests. The objective of this review is to compile and describe the studies aimed at establishing and elucidating the mechanisms of action of different biochemical compounds with antioxidant activities from marine species. In order to achieve that objective, the Scopus®, Web of Science™ and Microsoft Academic databases were used. Marine pigments represent a promising alternative to the antioxidants and synthetic additives used today. By establishing and understanding the mechanisms of action of the bioactive pigmented compounds isolated from marine organisms, it is possible to determine with greater precision their possible application in the industry.

3.
Foods ; 8(12)2019 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-31861248

RESUMEN

A strategy for food preservation, based on a methanol-HCl squid skin extract (Dosidicus gigas) (JSSE), was evaluated at two concentrations in yellowfin tuna fish pâtés, which were stored at 4 and 8 °C for 20 day. The JSSE was characterized by determining its antioxidant and mutagenic activities. A yellowfin tuna pâté was elaborated, with and without the addition of the JSSE. An affective sensory analysis was performed to establish consumers' preferences. During a 20-day storage period, the water activity (aw), pH, color difference (ΔE*ab), microbiological analysis, lipid oxidation and sensory quality attributes were evaluated, and the results were compared with the results of the butylated hydroxyanisole (BHA) and control treatments. The JSSE showed antioxidant activity against the 2,2-diphenyl-1-picrylhydrazyl (DPPH●+) and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS●) radicals and did not induce mutation, according to the Ames' Salmonella test, nor chromosomal abnormalities, according to the onion root-tip cell assay. The consumer analysis demonstrated a higher preference for the pâté with the added JSSE in seven out of the eight evaluated attributes. During storage, the JSSE neither had an impact on aw nor pH, maintained lower ΔE*ab values, inhibited the microbial activity and lipid oxidation (unlike the control pâté), and preserved the sensory quality attributes, unlike the BHA and control treatments. This study showed that the JSSE has biologically active pigments that can act as antioxidants and antimicrobials in yellowfin tuna fish pâtés.

4.
Molecules ; 24(19)2019 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-31547094

RESUMEN

Marine bioactive compounds have been found in very different sources and exert a very vast array of activities. Squid skin, normally considered a discard, is a source of bioactive compounds such as pigments. Recovering these compounds is a potential means of valorizing seafood byproducts. Until now, the structure and molecular properties of the bioactive pigments in jumbo squid skin (JSS) have not been established. In this study, methanol-HCl (1%) pigment extracts from JSS were fractionated by open column chromatography and grouped by thin-layer chromatography in order to isolate antioxidant pigments. Antioxidant activity was determined by the 2,2-diphenyl-1-picrylhydrazyl (DPPH●) and 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS●+) radical scavenging assays and ferric reducing power (FRAP) assay. Fractions 11-34 were separated and grouped according to flow rate values (F1-F8). Fractions F1, F3, and F7 had the lowest IC50 against ABTS●+ per milligram, and fractions F3 and F7 showed the lowest IC50 in the FRAP assay. Finally, fraction F7 had the highest DPPH● scavenging activity. The chemical structure of the F7 fraction was characterized by infrared spectroscopy, 1H nuclear magnetic resonance, and electrospray ionization-mass spectrometry. One of the compounds identified in the fraction was xanthommatin (11-(3-amino-3-carboxypropanoyl)-1-hydroxy-5-oxo-5H-pyrido[3,2-a]phenoxazine-3-carboxylic acid) and their derivatives (hydro- and dihydroxanthommatin). The results show that JSS pigments contain ommochrome molecules like xanthommatin, to which the antioxidant activity can be attributed.


Asunto(s)
Antioxidantes/química , Decapodiformes/química , Oxazinas/química , Piel/química , Xantenos/química , Animales , Cromatografía en Capa Delgada , Espectroscopía de Resonancia Magnética
5.
J Sci Food Agric ; 97(10): 3412-3419, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28009054

RESUMEN

BACKGROUND: An advanced strategy for chilled fish preservation, based on the inclusion in ice of an extract of jumbo squid (Dosidicus gigas) skin (JSS), is proposed. Aqueous solutions including acetic acid-ethanol extracts of JSS were tested at two different concentrations as icing media, with the effects on the quality evolution of chilled hake (Merluccius merluccius) being monitored. RESULTS: A significant inhibition (P < 0.05) of microbial activity (aerobes, psychrotrophs, Enterobacteriaceae, proteolytic bacteria; pH, trimethylamine) was obtained in hake corresponding to the icing batch including the highest JSS concentration. Additionally, fish specimens from such icing conditions showed an inhibitory effect (P < 0.05) on lipid hydrolysis development, while no effect (P > 0.05) was depicted for lipid oxidation. Sensory analysis (skin and mucus development; eyes; gills; texture; external odour; raw and cooked flesh odour; flesh taste) indicated a shelf life extension of chilled hake stored in ice including the highest JSS concentration. CONCLUSION: A profitable use of JSS, an industrial by-product during jumbo squid commercialisation, has been developed in the present work, which leads to a remarkable microbial inhibition and a significant shelf life extension of chilled hake. In agreement with previous research, ommochrome pigments (i.e. lipophilic-type compounds) would be considered responsible for this preservative effect. © 2016 Society of Chemical Industry.


Asunto(s)
Bacterias/crecimiento & desarrollo , Decapodiformes/química , Conservación de Alimentos/métodos , Gadiformes/microbiología , Alimentos Marinos/análisis , Piel/química , Animales , Bacterias/clasificación , Bacterias/genética , Bacterias/aislamiento & purificación , Recuento de Colonia Microbiana , Peces/microbiología , Contaminación de Alimentos/prevención & control , Odorantes/análisis , Alimentos Marinos/microbiología
6.
Rev. psiquiatr. salud ment ; 8(2): 83-91, abr.-jun. 2015. tab, graf
Artículo en Español | IBECS | ID: ibc-136992

RESUMEN

Introducción: Numerosos estudios internacionales han mostrado la eficacia de las intervenciones familiares psicoeducativas en la prevención de recaídas de personas con esquizofrenia. Aún existe controversia sobre los resultados en variables de carácter clínico y funcional, así como su aplicabilidad en la práctica clínica habitual. Objetivos: Evaluar la eficacia y la aplicabilidad de un programa de intervención unifamiliar, en comparación con el tratamiento habitual, en una muestra ambulatoria de pacientes con esquizofrenia, durante un periodo de 18 meses. Metodología: Ochenta y ocho familias fueron aleatorizadas en 2 grupos. El grupo experimental (n = 44) recibió un programa de intervención familiar durante 12 meses. El grupo control (n = 44) mantuvo su tratamiento habitual. Se realizaron evaluaciones en el momento inicial, a los 12 meses y a los 18 meses. La medida principal de resultado fue el número de hospitalizaciones, y como medidas secundarias se utilizaron la gravedad de la sintomatología clínica (BPRS) y el funcionamiento social (DAS II). Resultados: De los 88 pacientes reclutados, 74 completaron la evaluación a los 12 meses y 71 la evaluación final a los 18 meses. Los pacientes que siguieron intervención familiar redujeron un 40% el riesgo de hospitalización respecto a los pacientes que se mantuvieron con tratamiento habitual (p = 0,4018; IC 95%: 0,1833-0,6204). La sintomatología clínica mostró una mejoría significativa a los 12 meses (p = 0,0046) que dejó de serlo a los 18 meses (p = 0,4397). El nivel de discapacidad también se redujo de forma significativa, tanto a los 12 (p = 0,0511) como a los 18 meses (p = 0,0001) en el grupo tratado respecto al control. Conclusiones: Las intervenciones familiares psicoeducativas reducen el riesgo de hospitalización y mejoran el estado clínico y el funcionamiento social de las personas con esquizofrenia (AU)


Background: According to most relevant guidelines, family psycho-educational interventions are considered to be one the most effective psychosocial treatments for people with schizophrenia. The main outcome measure in controlled and randomized studies has been prevention of relapses and admissions, and encouragement of compliance, although some questions remain about its applicability and results in clinical practice. Objectives: The aim of study was to evaluate the efficacy and implementation of a single family psychoeducational intervention in ‘real’ conditions for people diagnosed with schizophrenia. Methods: A total of 88 families were randomized in two groups. The family intervention group received a 12 months psychoeducational treatment, and the other group followed normal standard treatment. Assessments were made at baseline, at 12 and at 18 months. The main outcome measure was hospitalization, and secondary outcome measures were clinical condition (BPRS-E) and social disability (DAS-II). Results: A total of 71 patients finished the study (34 family intervention group and 37 control group). Patients who received family intervention reduced the risk of hospitalization by 40% (P = .4018; 95% CI: 0.1833-0.6204). Symptomatology improved significantly at 12 months (P = .4018; 95% CI: 0.1833-0.6204), but not at 18 months (P = .4018; 95% CI: 0.1833-0.6204). Social disability was significantly reduced in the family intervention group at 12 months and 18 months. Conclusions: Family psychoeducational intervention reduces hospitalization risk and improves clinical condition and social functioning of people with schizophrenia (AU)


Asunto(s)
Humanos , Esquizofrenia/epidemiología , Terapia Familiar/métodos , Evaluación de Eficacia-Efectividad de Intervenciones , Hospitalización/estadística & datos numéricos , Apoyo Social , Servicios de Salud Mental/organización & administración
7.
Rev Psiquiatr Salud Ment ; 8(2): 83-91, 2015.
Artículo en Inglés, Español | MEDLINE | ID: mdl-25017624

RESUMEN

BACKGROUND: According to most relevant guidelines, family psycho-educational interventions are considered to be one the most effective psychosocial treatments for people with schizophrenia. The main outcome measure in controlled and randomized studies has been prevention of relapses and admissions, and encouragement of compliance, although some questions remain about its applicability and results in clinical practice. OBJECTIVES: The aim of study was to evaluate the efficacy and implementation of a single family psychoeducational intervention in 'real' conditions for people diagnosed with schizophrenia. METHODS: A total of 88 families were randomized in two groups. The family intervention group received a 12 months psychoeducational treatment, and the other group followed normal standard treatment. Assessments were made at baseline, at 12 and at 18 months. The main outcome measure was hospitalization, and secondary outcome measures were clinical condition (BPRS-E) and social disability (DAS-II). RESULTS: A total of 71 patients finished the study (34 family intervention group and 37 control group). Patients who received family intervention reduced the risk of hospitalization by 40% (P = .4018; 95%CI: 0.1833-0.6204). Symptomatology improved significantly at 12 months (P = .4018; 95%CI: 0.1833-0.6204), but not at 18 months (P = .4018; 95%CI: 0.1833-0.6204). Social disability was significantly reduced in the family intervention group at 12 months and 18 months. CONCLUSIONS: Family psychoeducational intervention reduces hospitalization risk and improves clinical condition and social functioning of people with schizophrenia.


Asunto(s)
Cuidadores , Familia , Educación en Salud/métodos , Hospitalización/estadística & datos numéricos , Relaciones Profesional-Familia , Esquizofrenia/terapia , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , España , Resultado del Tratamiento
8.
Curr Oncol Rep ; 14(5): 369-78, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22639108

RESUMEN

Cerebrospinal fluid-acute leukemia (CSF-acute leukemia) is a frequent and serious complication in patients with acute leukemia. One of the major problems of this complication is the diagnosis process itself. CSF cytology is currently considered the gold standard for establishing the diagnosis, a technique which presents various processing limitations, seriously impacting the predictive values. In the last 11 years, studies of CSF flow cytometry analysis done in patients with acute leukemia have demonstrated superiority in comparison with CSF cytology. Although comparative studies between these two techniques have been reported since 2001, no new consensus or formal changes to the gold standard have been established for the CSF acute leukemia diagnosis. The evidence suggests that positive flow cytometry cases, considered as indeterminate cases, will behave like disease in the central nervous system (CNS). Nevertheless, we think there are some variables and considerations that must be first evaluated under research protocols before CNS relapse can be established with only one positive flow cytometry analysis in the setting of indeterminate CSF samples. This paper proposes a diagnostic algorithm and complementary strategies.


Asunto(s)
Neoplasias del Sistema Nervioso Central/líquido cefalorraquídeo , Leucemia/líquido cefalorraquídeo , Enfermedad Aguda , Neoplasias del Sistema Nervioso Central/diagnóstico , Citometría de Flujo , Humanos , Leucemia/diagnóstico , Leucemia Mieloide Aguda/líquido cefalorraquídeo , Leucemia Promielocítica Aguda/líquido cefalorraquídeo , Imagen por Resonancia Magnética , Proteínas de Neoplasias/líquido cefalorraquídeo
9.
Radiographics ; 30(6): 1705-19, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21071384

RESUMEN

Neurocysticercosis is a neurologic parasitic disease caused by the encysted larva of the tapeworm Taenia solium and is the most important parasitic disease of the human central nervous system. It is the most common cause of acquired epilepsy in endemic settings and constitutes a public health challenge for most of the developing world. Nowadays, however, as a result of globalization, neurocysticercosis is being seen more frequently in developed countries as well. Neurocysticercosis is acquired through fecal-oral contamination, and the disease course is complex, with two intermediate hosts (ie, pigs and humans) and a definitive host (humans). Traditionally, it has been classified into active and nonactive forms according to disease location. Radiologists must be aware of its imaging appearance, which is quite variable, as is the differential diagnosis. Imaging findings depend on several factors, including the stage of the life cycle of T solium at presentation; the number and location (ie, subarachnoid, cisternal, or intraventricular) of parasites; and associated complications such as vascular involvement (ie, arteritis with or without infarction), inflammatory response (ie, edema, gliosis, or arachnoiditis), and, in ventricular forms, degree of obstruction. Thus, the diagnostic approach, management, and prognosis for neurocysticercosis differ widely depending on the type of infection.


Asunto(s)
Diagnóstico por Imagen , Neurocisticercosis/diagnóstico , Animales , Antihelmínticos/uso terapéutico , Diagnóstico Diferencial , Humanos , Estadios del Ciclo de Vida , Neurocisticercosis/tratamiento farmacológico , Neurocisticercosis/epidemiología , Neurocisticercosis/fisiopatología , Taenia solium/crecimiento & desarrollo , Taenia solium/fisiología
10.
Neurol Res ; 27(3): 314-8, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15845215

RESUMEN

OBJECTIVES: Prediction of intracerebral hemorrhage (ICH) in patients with cavernous angiomas is not totally elucidated. The aims of our study were to determine the rate of cerebral hemorrhage, its associated factors, and the clinical outcome in patients with cavernous angiomas in a Hispanic population. METHODS: We studied 133 patients with cavernous angiomas. The patients were classified into two groups depending on whether they presented an ICH. A comparative analysis of demographics and clinical data, neuroimaging characteristics, and prognosis was carried out in patients with and without hemorrhage. The hemorrhage rate (expressed as the percentage per patient per year) was also estimated. RESULTS: Seventy-eight patients (59%) had hemorrhage. Non-lobar location of angiomas was associated with hemorrhage [OR 4.82 (CI 95% 2.17-10.73; p=<0.001)]. In contrast, factors associated with a decreased risk of hemorrhage were a family history of epilepsy [OR 0.30 (CI 95% 0.10-0.79; p=0.016)] and lobar location of the angiomas [OR 0.21 (CI 95% 0.09-0.46; p=<0.001)]. The hemorrhagic rate of 1.71% per patient per year was influenced by the location. It was only 1.22% per patient per year in lobar angiomas and 2.33, 2.39, and 2.82% per patient per year for brainstem, cerebellum, and deep hemispheric angiomas, respectively. CONCLUSIONS: The non-lobar location of cavernous angiomas gives a higher risk of hemorrhage in our Mexican mestizo population, without the hemorrhage being related to either age or sex.


Asunto(s)
Hemorragia Cerebral/epidemiología , Hemorragia Cerebral/etiología , Hemangioma Cavernoso/complicaciones , Riesgo , Adulto , Demografía , Femenino , Estudios de Seguimiento , Escala de Consecuencias de Glasgow/estadística & datos numéricos , Hemangioma Cavernoso/clasificación , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Retrospectivos
11.
Stroke ; 34(10): 2453-8, 2003 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-14500936

RESUMEN

BACKGROUND AND PURPOSE: We investigated whether lacunar infarct (LI) patients with >1 lacune have different vascular risk factors, a different prognosis, and poorer functional outcome than those with a single lacune. METHODS: The study included 175 first-ever LI patients. The group was divided according to the presence of multiple (n=136) or single (n=39) LI. The association of single or multiple LI with the principal vascular risk factors, leukoaraiosis, outcome, and recurrence was investigated with logistic regression models that included age, sex, and cardiac disease. RESULTS: No significant differences were found between single and multiple LI with respect to age, hypertension, hyperlipidemia, smoking, and heavy alcohol drinking. Diabetes mellitus (odds ratio [OR], 2.43; 95% CI, 1.09 to 5.4), high levels of hematocrit (>0.47) (OR, 1.09; 95% CI, 1.04 to 1.21), and leukoaraiosis (OR, 3.58; 95% CI, 1.77 to 7.51) were significantly related to multiple but not to single LI. Stroke recurrence rate was 7.7% in patients with single LI and 24.3% in the multiple LI group (OR, 3.84; 95% CI, 1.1 to 13.3). During a median follow-up of 12 months (range, 6 to 156 months), 94% of the single LI patients and 77.2% of the multiple LI patients had favorable outcomes (Rankin Scale score 0 to 2) (OR, 5.4; 95% CI, 1.25 to 23.9). CONCLUSIONS: Diabetes mellitus, leukoaraiosis, and high levels of hematocrit are important risk factors in patients with >1 LI. The presence of multiple LI may be an important prognostic indicator not only for functional recovery but also for a higher rate of recurrence.


Asunto(s)
Infarto Encefálico/diagnóstico , Imagen por Resonancia Magnética , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , Infarto Encefálico/epidemiología , Infarto Encefálico/terapia , Trastornos Cerebrovasculares/epidemiología , Comorbilidad , Diabetes Mellitus/epidemiología , Femenino , Hematócrito , Humanos , Modelos Logísticos , Masculino , México/epidemiología , Persona de Mediana Edad , Análisis Multivariante , Variaciones Dependientes del Observador , Oportunidad Relativa , Valor Predictivo de las Pruebas , Pronóstico , Estudios Prospectivos , Recurrencia , Factores de Riesgo , Resultado del Tratamiento
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