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1.
J Integr Plant Biol ; 66(4): 787-809, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38477645

RESUMEN

The recretohalophyte Limonium bicolor thrives in high-salinity environments because salt glands on the above-ground parts of the plant help to expel excess salt. Here, we characterize a nucleus-localized C3HC4 (RING-HC)-type zinc finger protein of L. bicolor named  RING  ZINC  FINGER PROTEIN  1 (LbRZF1). LbRZF1 was expressed in salt glands and in response to NaCl treatment. LbRZF1 showed no E3 ubiquitin ligase activity. The phenotypes of overexpression and knockout lines for LbRZF1 indicated that LbRZF1 positively regulated salt gland development and salt tolerance in L. bicolor. lbrzf1 mutants had fewer salt glands and secreted less salt than did the wild-type, whereas LbRZF1-overexpressing lines had opposite phenotypes, in keeping with the overall salt tolerance of these plants. A yeast two-hybrid screen revealed that LbRZF1 interacted with LbCATALASE2 (LbCAT2) and the transcription factor LbMYB113, leading to their stabilization. Silencing of LbCAT2 or LbMYB113 decreased salt gland density and salt tolerance. The heterologous expression of LbRZF1 in Arabidopsis thaliana conferred salt tolerance to this non-halophyte. We also identified the transcription factor LbMYB48 as an upstream regulator of LbRZF1 transcription. The study of LbRZF1 in the regulation network of salt gland development also provides a good foundation for transforming crops and improving their salt resistance.


Asunto(s)
Arabidopsis , Plumbaginaceae , Animales , Tolerancia a la Sal/genética , Plumbaginaceae/genética , Plumbaginaceae/metabolismo , Glándula de Sal/metabolismo , Zinc/metabolismo , Arabidopsis/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Dedos de Zinc , Regulación de la Expresión Génica de las Plantas , Plantas Modificadas Genéticamente/metabolismo , Estrés Fisiológico/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
2.
Int J Biol Macromol ; 220: 1454-1463, 2022 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-36122773

RESUMEN

The effects of dielectric-barrier discharge (DBD) plasma treatment (20 s to 120 s treatment time with 40 kV, 12 kHz) induced mild oxidation on the gelling properties, and related structural changes of glycinin were investigated. The gelling ability of glycinin was improved by the mild oxidation induced by the plasma treatment. Treated glycinin gels exhibited a continuous and uniform network microstructure. Samples treated for 120 s had a 2.07-, 3.99- and 2.03-fold increase in hardness, chewiness, and resilience compared to the 20 s treated samples. Structural analyses showed that primary and secondary structures of glycinin were unaffected. The tertiary structure was shifted, accompanied by a decrease in free sulfhydryl (-SH) content. At the same time, carbonyl content and average particle diameter were increased by DBD treatment. The DBD treatment facilitated the generation/exchange of intermolecular disulfide bonds and enhanced gelling properties of glycinin. It is concluded that controlled plasma-induced protein oxidation can improve protein functionality.


Asunto(s)
Globulinas , Disulfuros/química , Geles , Globulinas/química , Proteínas de Soja/química
3.
Food Chem ; 363: 130300, 2021 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-34130101

RESUMEN

The effect of dielectric barrier discharge (DBD) plasma treatment times from 2 to 5 min at 40 kV on IgG/IgE binding capacity and functionality of soybean glycinin was examined. A substantial reduction in the binding capacity (91.64% for IgG and 81.49% for IgE) was obtained after 5 min of plasma treatment, as determined by western-blot and ELISA analyses. Further studies demonstrated that the elimination of antigenicity and allergenicity of glycinin was directly related to plasma-induced structural changes on two aspects. A conformational alteration caused by oxidation of peptide bond amino groups, accompanied with an oxidation of Trp, Tyr, and Phe amino acid residues, which was confirmed by surface hydrophobicity, multi-spectroscopic analysis, and amino acid analysis. The cleavage of polypeptide chains inevitably partially diminished the linear epitopes, resulting in a primary decline in IgG/IgE binding capacity. Additionally, an increase in the solubility from 10.78 ± 0.35 to 65.96 ± 1.86% and significant increase in the emulsifying ability from 21.08 ± 2.64 to 160.29 ± 4.12 m2/g were observed after treatment of the plasma for 2 min. The present results confirm the potential use of DBD for the production of hypoallergenic soy protein-based products and improving their technical functions such as solubility and emulsifying ability.


Asunto(s)
Globulinas , Proteínas de Soja , Alérgenos , Inmunoglobulina E , Inmunoglobulina G
4.
Food Chem ; 358: 129821, 2021 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-33933963

RESUMEN

The present study investigated the effects of dielectric-barrier-discharge (DBD) plasma treatment (12 kHz, 40 kV) at 1, 2, 3, and 4 min on the reduction of the immunoglobulin G (IgG) binding capacity of ß-lactoglobulin (ß-LG). The IgG binding capacity of ß-LG was reduced by 58.21% following a plasma treatment time of 4 min, as confirmed by western-blot and ELISA analyses. The reduction in IgG binding capacity of ß-LG was directly related to a stepwise change in its structure. The initial drop in the IgG binding capacity of ß-LG was found to be caused by conformational alteration, free sulfhydryl exposure and cross-linkage of molecules induced by oxidation of NH-/NH2- functional groups of peptide bonds and of sensitive amino acid residues (Tyr, Trp) as confirmed by SDS-PAGE, surface hydrophobicity and multi-spectroscopic analyses. Plasma treatment of more than 3 min resulted in cleavage of disulfidebonds and fragmentation of ß-LG that was confirmed by LC-MS/MS analysis, which resulted a further decline in the IgG binding capacity of ß-LG. Plasma treatment therefore has great potential as a substitute treatment for enzymatic hydrolysis for the production of hypoallergenic milk protein-based products.


Asunto(s)
Inmunoglobulina G/metabolismo , Lactoglobulinas/química , Lactoglobulinas/metabolismo , Alérgenos/química , Cromatografía Liquida , Electroforesis en Gel de Poliacrilamida , Ensayo de Inmunoadsorción Enzimática , Interacciones Hidrofóbicas e Hidrofílicas , Oxidación-Reducción , Gases em Plasma/química , Conformación Proteica , Espectrometría de Masas en Tándem
5.
Food Chem ; 340: 128198, 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33032147

RESUMEN

In this study, potential of dielectric-barrier discharge (DBD) plasma treatment (40 kV, 12 kHz at 1, 2, 3 and 4 min) to eliminate soybean agglutinin (SBA) activity was investigated in a SBA model system and soymilk. The plasma treatment decreased the SBA in the model system and hemagglutination activity was decreased by 87.31%. SDS-PAGE analysis confirmed the degradation of the SBA polypeptide chain. The multi-spectroscopic analysis revealed a two-stage structure alteration in the SBA upon exposure to the plasma treatment. Oxidation of NH-/NH2- at the peptide bond disrupted the hydrogen bonds and altered the secondary structure of SBA. Further oxidation of aromatic amino acid, cleavage of peptide bonds and the breakage of polypeptide led to the SBA fragmentation and complete unfolding of the protein. The SBA inactivation by the plasma treatment was confirmed in soymilk. Plasma treatment is a promising technology for the elimination of SBA in soybean product.


Asunto(s)
Lectinas de Plantas/química , Gases em Plasma/química , Proteínas de Soja/química , Impedancia Eléctrica , Enlace de Hidrógeno , Oxidación-Reducción , Estructura Secundaria de Proteína , Leche de Soja/química
6.
Environ Health ; 15(1): 90, 2016 08 30.
Artículo en Inglés | MEDLINE | ID: mdl-27576574

RESUMEN

BACKGROUND: Preventing suicide is a global imperative. Although the effects of social and individual risk factors of suicide have been widely investigated, evidence of environmental effects of exposure to air pollution is scarce. We investigated the effects of ambient air pollution on suicide mortality in Guangzhou, China during 2003-2012. METHODS: A conditional logistic regression analysis with a time-stratified case-crossover design was performed to assess the effects of daily exposure to three standard air pollutants, including particulate matter less than 10 µm in aerodynamic diameter (PM10), sulphur dioxide (SO2) and nitrogen dioxide (NO2), on suicide mortality, after adjusting for the confounding effects of daily mean temperature, relative humidity, atmospheric pressure and sunshine duration. Further analyses were stratified by season, gender, age group, educational attainment and suicide type. RESULTS: Between 2003 and 2012, there were a total of 1 550 registered suicide deaths in Guangzhou. A significant increase in suicide risk were associated with interquartile-range increases in the concentration of air pollutant, with an odds ratio of 1.13 (95 % confidence interval (CI): 1.01, 1.27) and 1.15 (95 % CI: 1.03, 1.28) for PM10 and NO2 at lag 02, and 1.12 (95 % CI: 1.02, 1.23) for SO2 at lag 01, respectively. The suicide risks related to air pollution for males and people with high education level were higher than for females and those with low education level, respectively. Significant air pollution effects were found on violent suicide mortality and in cool season but not on non-violent suicide mortality or in warm season. CONCLUSIONS: Suicide risk was positively associated with ambient air pollution levels. This finding would provide important information for the health impact assessment of air pollution and for the development of effective strategies and interventions for the prevention of suicide.


Asunto(s)
Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Dióxido de Nitrógeno/análisis , Material Particulado/análisis , Suicidio , Dióxido de Azufre/análisis , Anciano , China/epidemiología , Femenino , Humanos , Masculino , Oportunidad Relativa
7.
PLoS One ; 10(9): e0138146, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26382947

RESUMEN

BACKGROUND: Air pollution constitutes a significant stimulus of asthma exacerbations; however, the impacts of exposure to major air pollutants on asthma-related hospital admissions and emergency room visits (ERVs) have not been fully determined. OBJECTIVE: We sought to quantify the associations between short-term exposure to air pollutants [ozone (O3), carbon monoxide (CO), nitrogen dioxide (NO2), sulfur dioxide (SO2), and particulate matter ≤10 µm (PM10) and PM2.5] and the asthma-related emergency room visits (ERV) and hospitalizations. METHODS: Systematic computerized searches without language limitation were performed. Pooled relative risks (RRs) and 95% confidence intervals (95%CIs) were estimated using the random-effect models. Sensitivity analyses and subgroup analyses were also performed. RESULTS: After screening of 246 studies, 87 were included in our analyses. Air pollutants were associated with significantly increased risks of asthma ERVs and hospitalizations [O3: RR(95%CI), 1.009 (1.006, 1.011); I2 = 87.8%, population-attributable fraction (PAF) (95%CI): 0.8 (0.6, 1.1); CO: RR(95%CI), 1.045 (1.029, 1.061); I2 = 85.7%, PAF (95%CI): 4.3 (2.8, 5.7); NO2: RR(95%CI), 1.018 (1.014, 1.022); I2 = 87.6%, PAF (95%CI): 1.8 (1.4, 2.2); SO2: RR(95%CI), 1.011 (1.007, 1.015); I2 = 77.1%, PAF (95%CI): 1.1 (0.7, 1.5); PM10: RR(95%CI), 1.010 (1.008, 1.013); I2 = 69.1%, PAF (95%CI): 1.1 (0.8, 1.3); PM2.5: RR(95%CI), 1.023 (1.015, 1.031); I2 = 82.8%, PAF (95%CI): 2.3 (1.5, 3.1)]. Sensitivity analyses yielded compatible findings as compared with the overall analyses without publication bias. Stronger associations were found in hospitalized males, children and elderly patients in warm seasons with lag of 2 days or greater. CONCLUSION: Short-term exposures to air pollutants account for increased risks of asthma-related ERVs and hospitalizations that constitute a considerable healthcare utilization and socioeconomic burden.


Asunto(s)
Contaminantes Atmosféricos/análisis , Atención Ambulatoria/estadística & datos numéricos , Asma/epidemiología , Servicio de Urgencia en Hospital/estadística & datos numéricos , Material Particulado/análisis , Admisión del Paciente/estadística & datos numéricos , Anciano , Contaminación del Aire/análisis , Asma/terapia , Niño , Exposición a Riesgos Ambientales/análisis , Exposición a Riesgos Ambientales/estadística & datos numéricos , Humanos , Masculino , Estaciones del Año , Factores de Tiempo
8.
Malar J ; 14: 116, 2015 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-25881185

RESUMEN

BACKGROUND: The temporal variation of malaria incidence has been linked to meteorological factors in many studies, but key factors observed and corresponding effect estimates were not consistent. Furthermore, the potential effect modification by individual characteristics is not well documented. This study intends to examine the delayed effects of meteorological factors and the sub-population's susceptibility in Guangdong, China. METHODS: The Granger causality Wald test and Spearman correlation analysis were employed to select climatic variables influencing malaria. The distributed lag non-linear model (DLNM) was used to estimate the non-linear and delayed effects of weekly temperature, duration of sunshine, and precipitation on the weekly number of malaria cases after controlling for other confounders. Stratified analyses were conducted to identify the sub-population's susceptibility to meteorological effects by malaria type, gender, and age group. RESULTS: An incidence rate of 1.1 cases per 1,000,000 people was detected in Guangdong from 2005-2013. High temperature was associated with an observed increase in malaria incidence, with the effect lasting for four weeks and a maximum relative risk (RR) of 1.57 (95% confidence interval (CI): 1.06-2.33) by comparing 30°C to the median temperature. The effect of sunshine duration peaked at lag five and the maximum RR was 1.36 (95% CI: 1.08-1.72) by comparing 24 hours/week to 0 hours/week. A J-shaped relationship was found between malaria incidence and precipitation with a threshold of 150 mm/week. Over the threshold, precipitation increased malaria incidence after four weeks with the effect lasting for 15 weeks, and the maximum RR of 1.55 (95% CI: 1.18-2.03) occurring at lag eight by comparing 225 mm/week to 0 mm/week. Plasmodium falciparum was more sensitive to temperature and precipitation than Plasmodium vivax. Females had a higher susceptibility to the effects of sunshine and precipitation, and children and the elderly were more sensitive to the change of temperature, sunshine duration, and precipitation. CONCLUSION: Temperature, duration of sunshine and precipitation played important roles in malaria incidence with effects delayed and varied across lags. Climatic effects were distinct among sub-groups. This study provided helpful information for predicting malaria incidence and developing the future warning system.


Asunto(s)
Malaria/epidemiología , Conceptos Meteorológicos , Adolescente , Adulto , Niño , Preescolar , China/epidemiología , Femenino , Humanos , Incidencia , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Dinámicas no Lineales , Riesgo , Adulto Joven
9.
Adv Health Sci Educ Theory Pract ; 20(1): 163-79, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24906461

RESUMEN

Students' first-year academic success plays a critical role on their overall development in college, which implies the need to concentrate on identifying ways to improve students' first-year academic success. Different from most research on the subject, this study attempted to combine the sociological perspective of college impact with a psychological perspective to synthetically explore the causal relationship of specific types of self-concept and college involvement with academic success of medical students. A longitudinal study was conducted using 519 matriculates at a medical university in mainland China. We conducted the Cooperative Institutional Research Program freshmen survey and the Your First College Year survey to collect data of the pre-college and college academic and social self-concept, college involvement components, and some input characteristics. The academic success was measured by the first-year grade point average. A pathway analysis was conducted and showed the following results. Having high academic self-concept, being engaged in class and putting effort in homework or study directly contributes to increasing college achievement. Students' pre-college achievement and self-concept, faculty interaction, and homework involvement positively affected students' college academic self-concept development, which indirectly improved average grade point. These findings contribute to our understanding of a student's ability to interact with his or her collegiate environment and to experience academic success.


Asunto(s)
Logro , Educación de Pregrado en Medicina , Autoimagen , Estudiantes de Medicina/psicología , China , Evaluación Educacional , Femenino , Humanos , Estudios Longitudinales , Masculino , Encuestas y Cuestionarios , Adulto Joven
10.
BMC Med Educ ; 14: 87, 2014 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-24755355

RESUMEN

BACKGROUND: Although medical education has developed rapidly in the last decade, and the National College Entrance Examination (NCEE) is used as the "gold standard" for admission to medical college in mainland China, there is a lack of literature regarding the influence of NCEE score and other factors on the academic performance of medical students. This study aimed to examine potential predictors of first-year grade point average (GPA) for medical students. METHODS: This study included 1,285 students who matriculated at a first-tier medical university in mainland China in 2011. The precollege motivational attitudes for each matriculate were investigated via questionnaire. A hierarchical linear model was fitted to regress first-year GPA on a 100-point scale on NCEE score and other student-level and major-level characteristics. RESULTS: NCEE score was a significant predictor of both within-major and between-major variation of first-year GPA for medical students. Majors with higher mean NCEE scores had higher mean GPAs, and higher GPAs were observed among those individuals with higher NCEE scores after controlling for major-level characteristics. First-year GPA differed by certain individual socio-demographic variables. Female students had a 2.44-higher GPA on average than did male students. NCEE repeaters had a 1.55-lower GPA than non-repeaters. First-year GPA was associated negatively with parental income but positively with academic self-concept. CONCLUSIONS: NCEE score is an important predictor of the first-year GPA of medical students, but it is not the sole determinant. Individual socio-demographic characteristics and major-level characteristics should be taken into account to understand better and improve the first-year GPA of medical students.


Asunto(s)
Escolaridad , Estudiantes de Medicina/estadística & datos numéricos , China/epidemiología , Prueba de Admisión Académica , Evaluación Educacional , Femenino , Humanos , Estudios Longitudinales , Masculino , Facultades de Medicina/normas , Facultades de Medicina/estadística & datos numéricos , Factores Sexuales , Factores Socioeconómicos
11.
Environ Pollut ; 190: 75-81, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24732883

RESUMEN

There is an increasing interest in spatial and temporal variation of air pollution and its association with weather conditions. We presented the spatial and temporal variation of Air Pollution Index (API) and examined the associations between API and meteorological factors during 2001-2011 in Guangzhou, China. A Seasonal-Trend Decomposition Procedure Based on Loess (STL) was used to decompose API. Wavelet analyses were performed to examine the relationships between API and several meteorological factors. Air quality has improved since 2005. APIs were highly correlated among five monitoring stations, and there were substantial temporal variations. Timescale-dependent relationships were found between API and a variety of meteorological factors. Temperature, relative humidity, precipitation and wind speed were negatively correlated with API, while diurnal temperature range and atmospheric pressure were positively correlated with API in the annual cycle. Our findings should be taken into account when determining air quality forecasts and pollution control measures.


Asunto(s)
Contaminantes Atmosféricos/análisis , Contaminación del Aire/estadística & datos numéricos , Monitoreo del Ambiente/métodos , China , Clima , Conceptos Meteorológicos , Estaciones del Año , Análisis Espacio-Temporal , Temperatura , Tiempo (Meteorología) , Viento
12.
Environ Health ; 11: 63, 2012 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-22974173

RESUMEN

BACKGROUND: Although many studies have documented health effects of ambient temperature, little evidence is available in subtropical or tropical regions, and effect modifiers remain uncertain. We examined the effects of daily mean temperature on mortality and effect modification in the subtropical city of Guangzhou, China. METHODS: A Poisson regression model combined with distributed lag non-linear model was applied to assess the non-linear and lag patterns of the association between daily mean temperature and mortality from 2003 to 2007 in Guangzhou. The case-only approach was used to determine whether the effect of temperature was modified by individual characteristics, including sex, age, educational attainment and occupation class. RESULTS: Hot effect was immediate and limited to the first 5 days, with an overall increase of 15.46% (95% confidence interval: 10.05% to 20.87%) in mortality risk comparing the 99th and the 90th percentile temperature. Cold effect persisted for approximately 12 days, with a 20.39% (11.78% to 29.01%) increase in risk comparing the first and the 10th percentile temperature. The effects were especially remarkable for cardiovascular and respiratory mortality. The effects of both hot and cold temperatures were greater among the elderly. Females suffered more from hot-associated mortality than males. We also found significant effect modification by educational attainment and occupation class. CONCLUSIONS: There are significant mortality effects of hot and cold temperatures in Guangzhou. The elderly, females and subjects with low socioeconomic status have been identified as especially vulnerable to the effect of ambient temperatures.


Asunto(s)
Frío/efectos adversos , Calor/efectos adversos , Mortalidad , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Causas de Muerte , Niño , Preescolar , China/epidemiología , Modificador del Efecto Epidemiológico , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Dinámicas no Lineales , Análisis de Regresión , Adulto Joven
13.
Zhonghua Liu Xing Bing Xue Za Zhi ; 32(12): 1285-8, 2011 Dec.
Artículo en Chino | MEDLINE | ID: mdl-22336618

RESUMEN

To explore the role of confirmatory factor analysis in checking the construct validity of index system in clinical sciences and technologies and to determine the weighting of each index. Data were collected based on the achievements regarding the index system of sciences, technologies and analyzed by softwares SPSS and AMOS. Confirmatory factor analysis was performed to assess the construct validity and to identify the weighting. The P values for testing the two-order confirmatory factor models were bigger than 0.05, indicating that the actual data were in agreement with theory in designing the index system. Statistics on the goodness fit index (GFI) such as GFI were bigger than 0.90, indicating that they were satisfactory. Weightings for each index were identified based on factor loading of confirmatory factor analysis, showing that they were highly correlated with that from the Delphi method. Confirmatory factor analysis appeared to be an appropriate method in analyzing the associations among the index variables, and could be widely used to assess the construct validity of index system and identifying the weightings.


Asunto(s)
Logro , Estudios de Evaluación como Asunto , Medicina Clínica/estadística & datos numéricos , Análisis Factorial
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