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1.
Addict Biol ; 29(5): e13399, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38711213

RESUMEN

Excessive use of the internet, which is a typical scenario of self-control failure, could lead to potential consequences such as anxiety, depression, and diminished academic performance. However, the underlying neuropsychological mechanisms remain poorly understood. This study aims to investigate the structural basis of self-control and internet addiction. In a cohort of 96 internet gamers, we examined the relationships among grey matter volume and white matter integrity within the frontostriatal circuits and internet addiction severity, as well as self-control measures. The results showed a significant and negative correlation between dACC grey matter volume and internet addiction severity (p < 0.001), but not with self-control. Subsequent tractography from the dACC to the bilateral ventral striatum (VS) was conducted. The fractional anisotropy (FA) and radial diffusivity of dACC-right VS pathway was negatively (p = 0.011) and positively (p = 0.020) correlated with internet addiction severity, respectively, and the FA was also positively correlated with self-control (p = 0.036). These associations were not observed for the dACC-left VS pathway. Further mediation analysis demonstrated a significant complete mediation effect of self-control on the relationship between FA of the dACC-right VS pathway and internet addiction severity. Our findings suggest that the dACC-right VS pathway is a critical neural substrate for both internet addiction and self-control. Deficits in this pathway may lead to impaired self-regulation over internet usage, exacerbating the severity of internet addiction.


Asunto(s)
Imagen de Difusión Tensora , Sustancia Gris , Trastorno de Adicción a Internet , Autocontrol , Sustancia Blanca , Humanos , Sustancia Blanca/diagnóstico por imagen , Sustancia Blanca/patología , Masculino , Trastorno de Adicción a Internet/diagnóstico por imagen , Trastorno de Adicción a Internet/fisiopatología , Femenino , Imagen de Difusión Tensora/métodos , Adulto , Adulto Joven , Sustancia Gris/diagnóstico por imagen , Sustancia Gris/patología , Estriado Ventral/diagnóstico por imagen , Estriado Ventral/fisiopatología , Estriado Ventral/patología , Índice de Severidad de la Enfermedad , Vías Nerviosas/diagnóstico por imagen , Vías Nerviosas/fisiopatología , Cuerpo Estriado/diagnóstico por imagen , Cuerpo Estriado/patología , Cuerpo Estriado/fisiopatología , Internet , Lóbulo Frontal/diagnóstico por imagen , Lóbulo Frontal/patología , Lóbulo Frontal/fisiopatología
2.
Addict Biol ; 27(5): e13210, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-36001435

RESUMEN

Self-control is important for long-term success and could be a protective factor against maladaptive behaviours such as excessive gaming activity or Internet gaming disorder (IGD). However, the neurobiological basis of self-control and its relationship to IGD remain elusive. Using resting-state fMRI data from 89 participants aged from 18 to 26, we found that self-control and the number of IGD symptoms (IGD-S) were positively and negatively correlated with functional connectivity between right ventral striatum (rVS) and dorsal anterior cingulate cortex (dACC), respectively. A mediation analysis indicated that self-control influenced IGD-S partially through the rVS-dACC connectivity. In addition, step-wise regression analyses revealed that the rVS connectivity in a reward-anticipation limbic pathway contributed to IGD-S but not self-control, independent of the dACC pathway. These results suggest that the cingulate-ventral striatal functional connectivity may serve as an important neurobiological underpinning of self-control to regulate maladaptive behaviours such as these manifesting IGD through striatal circuitry balance.


Asunto(s)
Conducta Adictiva , Estriado Ventral , Juegos de Video , Humanos , Conducta Adictiva/diagnóstico por imagen , Encéfalo , Mapeo Encefálico/métodos , Giro del Cíngulo/diagnóstico por imagen , Internet , Trastorno de Adicción a Internet , Imagen por Resonancia Magnética , Vías Nerviosas/diagnóstico por imagen , Estriado Ventral/diagnóstico por imagen
3.
Pest Manag Sci ; 78(6): 2512-2522, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35318795

RESUMEN

BACKGROUND: Unmanned aerial vehicles (UAVs) are widely used to improve the efficiency of pesticide applications. Low-volume spraying operations require more efficient deposition of droplets on the target surface. Therefore, pesticide deposition and retention on plant surfaces is a serious challenge for modern precision agriculture. Tank-mix adjuvants have been used to improve spray dilutions performance; however, their effects on the physicochemical properties of spray dilutions, dosage delivery, and pesticide dosage are unclear. RESULTS: Tank-mix adjuvant 8860 significantly improved the physicochemical properties of spray dilutions, inhibited spray droplets rebound, improved the wetting and spreading performance of spray dilutions on wheat leaves, and increased the effective deposition of tebuconazole on wheat leaves. Even when its dosage was reduced by one-third, the spray solution still showed excellent disease control and effective deposition of the active ingredient on wheat leaves. CONCLUSION: The use of appropriate tank-mix adjuvants in UAV-based plant protection for wheat can significantly improve the performance of spray dilutions, increase the efficiency of pesticide dosage delivery, and improve disease control. These adjuvants can also help reduce the pesticide use while ensuring their effectiveness. © 2022 Society of Chemical Industry.


Asunto(s)
Plaguicidas , Agricultura , Plaguicidas/análisis , Triticum , Dispositivos Aéreos No Tripulados , Humectabilidad
4.
Front Plant Sci ; 10: 1376, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31849999

RESUMEN

The monoterpenes linalool and its oxides are the key aroma-active compounds in Osmanthus fragrans Lour. flowers. The glycosides of these monoterpenes accumulate throughout flowering, leading to considerable storage of potential aroma constituents that account for the majority of non-volatile aroma compounds. However, the UDP-glycosyltransferase (UGT) responsible for the glycosylation of linalool and its oxides has not been clarified. Four candidate OfUGTs (UGT85A82, UGT85A83, UGT85AF3, and UGT85A84) with high homology to the known terpenoid UGTs were screened by transcriptome sequencing. Over-expression of the candidate OfUGTs in tobacco showed that UGT85A84 glycosylated linalool oxides in planta. Since the transcript levels of UGT85A84 were positively correlated with glycoside accumulation, the recombinant UGT85A84 protein was subjected to reactions with aglycones and sugar donors. Two formate adducts were exclusively detected in UDP-Glc with linalool and linalool oxide reactions by liquid chromatography-mass spectrometry (LC-MS), indicating that UDP-Glc was the specific sugar donor. The kinetic parameters demonstrated that UGT85A84 glycosylated both linalool and lianlool oxides in vitro. Further analysis demonstrated that the transcription levels of MEP pathway genes might play an important role in mediating terpenoid glycosylation. Our findings unraveled the mechanism underlying the glycosylation of essential aroma compounds in flowers. This study will facilitate the application of potential aroma contributors in future industries.

5.
Chin Med J (Engl) ; 129(6): 696-701, 2016 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-26960373

RESUMEN

BACKGROUND: Antimicrobial peptides, including cathelicidin LL-37, human beta defensin (HBD)-2, and HBD-3, are important elements of the innate immune response and involved in modulation of the adaptive immunity, and they also play an important role in cutaneous defense against Mycobacterium tuberculosis. METHODS: The fresh skin tissues and paraffin-embedded biopsy samples from three cutaneous tuberculosis, two tuberculids, and ten healthy individuals were collected. The expressions of LL-37, HBD-2, and HBD-3 mRNA in the lesions of three cutaneous tuberculosis and two tuberculids were detected by quantitative real-time polymerase chain reaction; the protein expressions were detected by immunohistochemistry and Western blotting methods. RESULTS: The expressions of LL-37 mRNA and protein in the lesions of cutaneous tuberculosis and tuberculids were similar to that of normal skin. The expression of HBD-2 mRNA had an increasing trend in the lesions of cutaneous tuberculosis and tuberculids compared with that of normal skin; however, the expression of HBD-2 protein in the lesions of cutaneous tuberculosis had a decreasing trend compared with that of normal skin, and the expression of HBD-2 protein in the lesions of tuberculids was similar to that of normal skin. The expressions of HBD-3 mRNA and protein in lesions of cutaneous tuberculosis and tuberculids were similar to that of normal skin. CONCLUSIONS: Our study indicated that the expression of HBD-2 and HBD-3 mRNA and protein in lesions of cutaneous tuberculosis may be not consistent with that of tuberculids. However, an inherent limitation of the present study was that the sample size was small, and the roles and regulation mechanisms of LL-37, HBD-2, and HBD-3 in cutaneous tuberculosis and tuberculids need to be further investigated.


Asunto(s)
Péptidos Catiónicos Antimicrobianos/genética , Tuberculosis Cutánea/metabolismo , beta-Defensinas/genética , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , ARN Mensajero/análisis , Catelicidinas
7.
Plant Cell Environ ; 35(3): 534-45, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21951070

RESUMEN

The biosynthesis of volatile compounds in plants is affected by environmental conditions. Lactones are considered to be peach-like aroma volatiles; however, no enzymes or genes associated with their biosynthesis have been characterized. White-fleshed (cv. Hujingmilu) and yellow-fleshed (cv. Jinxiu) melting peach (Prunus persica L. Batsch) fruit were used as materials in two successive seasons and responses measured to four different temperature treatments. Five major lactones accumulated during postharvest peach fruit ripening at 20 °C. Peach fruit at 5 °C, which induces chilling injury (CI), had the lowest lactone content during subsequent shelf life after removal, while 0 °C and a low-temperature conditioning (LTC) treatment alleviated development of CI and maintained significantly higher lactone contents. Expression of PpACX1 and activity of acyl-CoA oxidase (ACX) with C16-CoA tended to increase during postharvest ripening both at 20 °C and during shelf life after removal from cold storage when no CI was developed. There was a positive correlation between ACX and lactones in peach fruit postharvest. Changes in lactone production in response to temperatures are suggested to be a consequence of altered expression of PpACX1 and long-chain ACX activity.


Asunto(s)
Acil-CoA Oxidasa/metabolismo , Frutas/metabolismo , Lactonas/metabolismo , Prunus/enzimología , Temperatura , Compuestos Orgánicos Volátiles/metabolismo , Acil-CoA Oxidasa/genética , ADN de Plantas/genética , Almacenamiento de Alimentos , Frutas/enzimología , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Prunus/genética , Análisis de Secuencia de ADN
8.
J Agric Food Chem ; 58(10): 6157-65, 2010 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-20415420

RESUMEN

Changes in characteristic aroma volatiles, levels of fatty acids as aroma precursors, and expression patterns of related genes, including lipoxygenase (LOX), hydroperoxide lyase (HPL), alcohol dehydrogenase (ADH), alcohol acyltransferase (AAT), and fatty acid desaturase (FAD), were studied in peach ( Prunus persica L. Batsch., cv. Yulu) fruit during postharvest ripening at 20 degrees C. Concentrations of n-hexanal, (E)-2-hexenal, (E)-2-hexenol, and (Z)-3-hexenol decreased, whereas the production of (Z)-3-hexenyl acetate, gamma-hexalactone, gamma-octalactone, gamma-decalactone, and delta-decalactone increased with fruit ripening. Lactones showed a clear pattern concomitant with the climacteric rise in ethylene production, with gamma-decalactone being the principal volatile compound at the late ripening stage. Of the LOX family genes, PpLOX2 and PpLOX3 had relatively high transcript levels initially followed by a decline with fruit ripening, while levels of PpLOX1 and PpLOX4 transcripts were upregulated by accumulated ethylene production. Expression of PpHPL1, PpADH1, PpADH2, and PpADH3 showed similar decreasing patterns during ripening. Expression levels of PpAAT1 showed a rapid increase during the first 2 days of postharvest ripening followed by a gradual decrease. Contents of polyunsaturated linoleic and linolenic acids increased, and saturated palmitic acid levels tended to decline as the fruit ripened. The increased levels of unsaturated fatty acids closely paralleled increasing expression of PpFAD1 and PpFAD2. The significance of gene expression changes in relation to aroma volatile production is discussed.


Asunto(s)
Ácidos Grasos/metabolismo , Frutas/crecimiento & desarrollo , Frutas/genética , Expresión Génica , Odorantes/análisis , Prunus/genética , Aciltransferasas/genética , Alcohol Deshidrogenasa/genética , Aldehído-Liasas/genética , Sistema Enzimático del Citocromo P-450/genética , Etilenos/biosíntesis , Ácido Graso Desaturasas/genética , Ácidos Grasos/análisis , Frutas/química , Lactonas/análisis , Lipooxigenasa/genética , Compuestos Orgánicos Volátiles/análisis , Compuestos Orgánicos Volátiles/metabolismo
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