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1.
Phys Chem Chem Phys ; 26(2): 788-807, 2024 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-38088777

RESUMEN

Ultrafast excited-state dynamics of the simplest nitrostilbenes, namely trans-4-nitrostilbene (t-NSB), was studied in solvents of various polarities with ultrafast broadband time-resolved fluorescence and transient absorption spectroscopies, and by quantum-chemical computations. The results revealed that the initially excited S1(ππ*) state deactivation dynamics is strongly influenced by the solvent polarity. Specifically, the t-NSB S1-state lifetime decreases by three orders of magnitude from ∼60 ps in high-polarity solvents to ∼60 fs in nonpolar solvents. The strong solvent-polarity dependence arises from the differences in dipole moments among the S1 and relevant states, including the major intersystem crossing (ISC) receiver triplet states, and therefore, the solvent polarity can modulate their relative energies and ISC rates. In nonpolar solvents, the sub-100 fs lifetime is due to a combination of efficient ISC and internal conversion. In medium-polarity solvents, the S1-state population decays via a competing ISC relaxation mechanism in a biphasic manner, and the ISC rates are found to obey the inverse energy gap law of the strong coupling case. In high-polarity solvents, the S1 state is stabilized to a much lower energy such that ISC becomes energetically infeasible, and the S1 state decays via barrier crossing along the torsion angle of the central ethylenic bond to the nonfluorescent perpendicular configuration. Regardless of the initial S1-state deactivation pathways in various solvents, the excited-state population is ultimately trapped in the metastable T1-state perpendicular configuration, at which a slower ISC occurs to bring the system to the ground state and bifurcate into either trans or cis form of NSB.

2.
Memory ; 27(3): 387-396, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30142023

RESUMEN

Evidence has demonstrated that sleep-related memory consolidation declines in ageing. However, little is known about age-related changes to sleep-related emotional memory consolidation, especially when considering the positivity effect observed in older adults. In the present study, we sought to explore whether there is a positive emotional bias in sleep-related memory consolidation among healthy older adults. Young and older adults were randomly assigned either into a sleep or wake condition. All participants encoded positive, negative, and neutral stimuli and underwent recognition tests immediately (test 1), after a 12-hour sleep/wake interval (test 2), and 3 days after test 2 (test 3). Results showed that age-related differences of sleep beneficial effect were modulated by emotion valence. In particular, sleep selectively enhanced positive memory in older adults, while in young adults sleep beneficial effect was manifested in neutral memory. Moreover, the sleep beneficial effect can be maintained at least 3 days in both young and older adults. These findings suggest that older adults had preserved but positive bias of sleep-related memory consolidation, which could be one of the underlying mechanisms for their generally better emotional well-being in daily life. These findings highlight the dynamic interplay among sleep and emotional memory in older adults.


Asunto(s)
Envejecimiento , Emociones , Consolidación de la Memoria/fisiología , Sueño/fisiología , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reconocimiento en Psicología , Adulto Joven
3.
Psychiatry Res ; 339: 116049, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38924898

RESUMEN

Cannabidiol (CBD), as one of the phytocannabinoids, has a wide range of therapeutic properties for various neuropsychiatric disorders due to central nervous system effects. These therapeutic properties demonstrated by preclinical and clinical studies encompass more than just anticonvulsant, anti-arthritic, analgesic, anti-inflammatory, antioxidant, antitumor, antiemetic, antipsychotic and neuroprotective effects. It has been hypothesized that CBD holds potential in the treatment of various neuropsychiatric and anxiety disorders. Thus, PRISMA was used as a guide for our systematic review. Eight of the 1550 articles screened in June 2023 were eligible for meta-analysis. Based on the 316 participants included in these eight articles, this meta-analysis revealed a substantial significant impact of CBD on anxiety with a considerable effect size (Hedges' g = -0.92, 95% CI -1.80 to -0.04). In addition, this meta-analysis focuses on the efficacy of CBD in treating anxiety disorders such as generalized anxiety disorder (GAD), social anxiety disorder (SAD), and post-traumatic stress disorder (PTSD). However, caution should be exercised in interpreting our findings due to the limited size of the clinical sample, and additional trials ought to be carried out if deemed necessary.


Asunto(s)
Trastornos de Ansiedad , Cannabidiol , Cannabidiol/uso terapéutico , Cannabidiol/farmacología , Humanos , Trastornos de Ansiedad/tratamiento farmacológico , Ansiolíticos/uso terapéutico , Ansiolíticos/farmacología
4.
ACS Appl Mater Interfaces ; 16(12): 15073-15083, 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38478772

RESUMEN

LaCrO3 (LCO) has promising applications as a p-type conductive material in the fields of transparent conducting oxes, high-temperature sensors, and magnetohydrodynamic power generators. However, the easy volatility of the Cr element, along with the issues of low electrical conductivity caused by the small-polaron conduction mechanism and wide band gap, has hindered the widespread application of LCO. In this work, based on band engineering and defect engineering, we screened doping schemes through first-principles calculations that can reduce Cr volatility by enhancing the Cr-O bond energy. We also aimed to promote small-polaron hopping and improve the electrical conductivity by introducing impurity levels. Additionally, we conducted a thorough analysis of the small-polaron conductivity mechanism. Through the solid-state method, we successfully prepared codoped LCO with Ca and Zn. The Zn dopants effectively enhanced the Cr-O bond strength, suppressed the Cr volatility, and improved high-temperature stability. The Zn dopants introduced additional impurity energy levels within the band gap, significantly changing the mobility of small polarons. Through optimal doping concentration, the La0.7Ca0.3Cr0.95Zn0.05O3 sample demonstrated a significant enhancement in electrical conductivity compared to La0.7Ca0.3CrO3, increasing from 7 to 60 at 1000 K. Additionally, the impurity energy levels enhanced the asymmetry near the Fermi level, resulting in an increased Seebeck coefficient (S). This is beneficial for the production of high-temperature sensors. The output voltage of an LCO thermocouple module reaches up to 58 mV at 2170 K, indicating that the performance optimization strategy employed in this work has significant implications for the regulation and application of oxide electrical materials.

5.
Behav Brain Funct ; 8: 29, 2012 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-22676227

RESUMEN

BACKGROUND: Neurological abnormalities have been reported in people with amnestic mild cognitive impairment (aMCI). The current study aimed to examine the prevalence of neurological soft signs (NSS) in this clinical group and to examine the relationship of NSS to other neuropsychological performances. METHODS: Twenty-nine people with aMCI and 28 cognitively healthy elderly people were recruited for the present study. The NSS subscales (motor coordination, sensory integration, and disinhibition) of the Cambridge Neurological Inventory and a set of neuropsychological tests were administered to all the participants. RESULTS: People with aMCI exhibited significantly more motor coordination signs, disinhibition signs, and total NSS than normal controls. Correlation analysis showed that the motor coordination subscale score and total score of NSS were significantly inversely correlated with the combined Z-score of neuropsychological tests in aMCI group. CONCLUSIONS: These preliminary findings suggested that people with aMCI demonstrated a higher prevalence of NSS compared to healthy elderly people. Moreover, NSS was found to be inversely correlated with the neuropsychological performances in persons with aMCI. When taken together, these findings suggested that NSS may play a potential important role and serve as a tool to assist in the early detection of aMCI.


Asunto(s)
Amnesia/psicología , Disfunción Cognitiva/psicología , Actividades Cotidianas , Anciano , Anciano de 80 o más Años , Cognición , Función Ejecutiva , Femenino , Humanos , Masculino , Memoria , Persona de Mediana Edad , Destreza Motora , Examen Neurológico , Pruebas Neuropsicológicas
6.
Sci Adv ; 7(36): eabh2450, 2021 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-34516912

RESUMEN

Accumulation of iron in seeds is essential for both plant reproduction and human nutrition. Transport of iron to seeds requires the chelator nicotianamine (NA) to prevent its precipitation in the plant vascular tissues. However, how NA is transported to the apoplast for forming metal-NA complexes remains unknown. Here, we report that two members of the nitrate/peptide transporter family, NAET1 and NAET2, function as NA transporters required for translocation of both iron and copper to seeds. We show that NAET1 and NAET2 are predominantly expressed in the shoot and root vascular tissues and mediate secretion of NA out of the cells in resembling the release of neurotransmitters from animal synaptic vesicles. These findings reveal an unusual mechanism of transmembrane transport in plants and uncover a fundamental aspect of plant nutrition that has implications for improving food nutrition and human health.

7.
Sci China Life Sci ; 63(5): 635-674, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32246404

RESUMEN

Abiotic stresses and soil nutrient limitations are major environmental conditions that reduce plant growth, productivity and quality. Plants have evolved mechanisms to perceive these environmental challenges, transmit the stress signals within cells as well as between cells and tissues, and make appropriate adjustments in their growth and development in order to survive and reproduce. In recent years, significant progress has been made on many fronts of the stress signaling research, particularly in understanding the downstream signaling events that culminate at the activation of stress- and nutrient limitation-responsive genes, cellular ion homeostasis, and growth adjustment. However, the revelation of the early events of stress signaling, particularly the identification of primary stress sensors, still lags behind. In this review, we summarize recent work on the genetic and molecular mechanisms of plant abiotic stress and nutrient limitation sensing and signaling and discuss new directions for future studies.


Asunto(s)
Plantas/genética , Plantas/metabolismo , Suelo/química , Estrés Fisiológico/fisiología , Canales de Calcio/metabolismo , Regulación de la Expresión Génica de las Plantas , Metales Pesados/metabolismo , Fosforilación , Desarrollo de la Planta/genética , Proteínas de Plantas/metabolismo , Transducción de Señal , Estrés Fisiológico/genética , Factores de Transcripción/metabolismo
8.
Int J Bioprint ; 5(2): 168, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-32782982

RESUMEN

Additive manufacturing has been used in complex spinal surgical planning since the 1990s and is now increasingly utilized to produce surgical guides, templates, and more recently customized implants. Surgeons report beneficial impacts using additively manufactured biomodels as pre-operative planning aids as it generally provides a better representation of the patient's anatomy than on-screen viewing of computed tomography (CT) or magnetic resonance imaging (MRI). Furthermore, it has proven to be very beneficial in surgical training and in explaining complex deformity and surgical plans to patients/parents. This paper reviews the historical perspective, current use, and future directions in using additive manufacturing in complex spinal surgery cases. This review reflects the authors' opinion of where the field is moving in light of the current literature. Despite the reported benefits of additive manufacturing for surgical planning in recent years, it remains a high niche market. This review raises the question as to why the use of this technology has not progressed more rapidly despite the reported advantages - decreased operating time, decreased radiation exposure to patients intraoperatively, improved overall surgical outcomes, pre-operative implant selection, as well as being an excellent communication aid for all medical and surgical team members. Increasingly, the greatest benefits of additive manufacturing technology in spinal surgery are custom-designed drill guides, templates for pedicle screw placement, and customized patient-specific implants. In view of these applications, additive manufacturing technology could potentially revolutionize health care in the near future.

9.
Int J Bioprint ; 5(2): 232, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-32954041

RESUMEN

[This retracts the article on p. 168 in vol. 5, PMID: 32782982.].

10.
Sci Rep ; 8(1): 6182, 2018 04 18.
Artículo en Inglés | MEDLINE | ID: mdl-29670225

RESUMEN

Interleukin-13 (IL-13) has important functions in atherosclerosis, but its role in coronary artery disease (CAD) is unclear. Here, we studied the genetic role of IL-13 in CAD in a Chinese Han population using tag SNPs covering the whole IL13 gene (i.e., rs1881457, rs2069744 and rs20541) and a two-stage cohort containing 1863 CAD cases and 1841 controls. Traditional risk factors for CAD, such as age, BMI, and other factors, were used as covariates in logistic regression analysis. In the total population, we found that two haplotypes of IL13 (ATG and ATA, ordered rs1881457C-rs2069744T-rs20541A) significantly contributed to the risk of CAD with adjusted p values less than 0.05 (padj = 0.019 and padj = 0.042, respectively). In subgroup population analyses, the variant rs1881457C was found to significantly contribute to a nearly two fold increase in the risk of CAD in men (padj = 0.023, OR = 1.91, 95% CI: 1.09-3.33). The variant rs1881457C also significantly contributed to a nearly twofold risk of late-onset CAD (padj = 0.024, OR = 1.93, 95% CI: 1.09-3.42). In conclusion, IL13 might be involved in CAD via different mechanisms under different conditions in the Chinese Han population.


Asunto(s)
Pueblo Asiatico/genética , Enfermedad de la Arteria Coronaria/etiología , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Interleucina-13/genética , Adulto , Alelos , Estudios de Casos y Controles , China/epidemiología , Comorbilidad , Enfermedad de la Arteria Coronaria/epidemiología , Enfermedad de la Arteria Coronaria/metabolismo , Femenino , Humanos , Interleucina-13/metabolismo , Desequilibrio de Ligamiento , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Polimorfismo de Nucleótido Simple , Medición de Riesgo
11.
Front Immunol ; 9: 1775, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30123216

RESUMEN

The thymic stromal lymphopoietin (TSLP)/TSLP receptor (TSLPR) axis is involved in multiple inflammatory immune diseases, including coronary artery disease (CAD). To explore the causal relationship between this axis and CAD, we performed a three-stage case-control association analysis with 3,628 CAD cases and 3,776 controls using common variants in the genes TSLP, interleukin 7 receptor (IL7R), and TSLPR. Three common variants in the TSLP/TSLPR axis were significantly associated with CAD in a Chinese Han population [rs3806933T in TSLP, Padj = 4.35 × 10-5, odds ratio (OR) = 1.18; rs6897932T in IL7R, Padj = 1.13 × 10-7, OR = 1.31; g.19646A>GA in TSLPR, Padj = 2.04 × 10-6, OR = 1.20]. Reporter gene analysis demonstrated that rs3806933 and rs6897932 could influence TSLP and IL7R expression, respectively. Furthermore, the "T" allele of rs3806933 might increase plasma TSLP levels (R2 = 0.175, P < 0.01). In a stepwise procedure, the risk for CAD increased by nearly fivefold compared with the maximum effect of any single variant (Padj = 6.99 × 10-4, OR = 4.85). In addition, the epistatic interaction between TSLP and IL33 produced a nearly threefold increase in the risk of CAD in the combined model of rs3806933TT-rs7025417TT (Padj = 3.67 × 10-4, OR = 2.98). Our study illustrates that the TSLP/TSLPR axis might be involved in the pathogenesis of CAD through upregulation of mRNA or protein expression of the referenced genes and might have additive effects on the CAD risk when combined with IL-33 signaling.


Asunto(s)
Enfermedad de la Arteria Coronaria/etiología , Enfermedad de la Arteria Coronaria/metabolismo , Citocinas/genética , Epistasis Genética , Regulación de la Expresión Génica , Interleucina-33/genética , Receptores de Citocinas/genética , Anciano , Alelos , Estudios de Casos y Controles , China , Enfermedad de la Arteria Coronaria/diagnóstico , Enfermedad de la Arteria Coronaria/mortalidad , Citocinas/sangre , Citocinas/metabolismo , Femenino , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Interleucina-33/metabolismo , Desequilibrio de Ligamiento , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Polimorfismo de Nucleótido Simple , Modelos de Riesgos Proporcionales , Receptores de Citocinas/metabolismo , Receptores de Interleucina-7/genética , Transducción de Señal , Linfopoyetina del Estroma Tímico
12.
Beijing Da Xue Xue Bao Yi Xue Ban ; 38(5): 541-7, 2006 Oct 18.
Artículo en Zh | MEDLINE | ID: mdl-17068632

RESUMEN

Recently, the pharmacological study of Ganoderma spores and active components has become a focus of attention in the world. The present review is based on the auctorial research on Ganoderma spores. It involves pharmacological effects of Ganoderma spores and its active components, including immunomodulating effect, antitumor activity and its mechanism in vivo and in vitro, liver-protective effect, gastric ulcer preventing effect, serum glucose and blood fat depressing effects, anti-hypoxia and scavenging free redical, etc. The possible problems and their solutions in this research area are also discussed.


Asunto(s)
Adyuvantes Inmunológicos/farmacología , Antineoplásicos/farmacología , Ganoderma/química , Esporas Fúngicas/química , Depuradores de Radicales Libres/farmacología
13.
Beijing Da Xue Xue Bao Yi Xue Ban ; 37(6): 569-74, 2005 Dec 18.
Artículo en Zh | MEDLINE | ID: mdl-16378103

RESUMEN

OBJECTIVE: To compare the immunomodulatory effects of spore polysaccharides (Gl-SP) and broken spore polysaccharides (Gl-BSP) isolated from Ganoderma lucidum(Leyss et Fr.) Karst. on murine splenic lymphocytes and peritoneal macrophages in vitro. METHODS: Mixed lymphocyte culture reaction (MLR), lymphocyte proliferation in the presence or absence of mitogen, and the cytotoxic activity of splenic natural killer (NK) cells were detected with MTT assay in vitro. The percentage of phagocytosis of neutral red (NR) by mouse peritoneal macrophages was detected by colorimetric assay. Splenic T-lymphocyte subpopulations were measured with flow cytometry(FCM). IL-2, IFN-gamma and TNF-alpha in the culture supernatants were detected by ELISA and biological assay. Nitric oxide (NO) production was examined by Griess reaction. RESULTS: At the concentration range of 0.2-12.8 mg/L, Gl-SP and Gl-BSP were shown to increase lymphocyte proliferation in the presence or absence of mitogen, enhance NK cytotoxic activity, augment the production of TNF-alpha and NO in Gl-SP- or Gl-BSP-activated macrophages, as well the percentage of phagocytosis of NR by macrophages in vitro. Both Gl-SP and Gl-BSP could promote MLR, however, at the dose of 12.8 mg/L, Gl-BSP showed higher activity than Gl-SP in the proliferation of lymphocytes. These two kinds of polysaccharide could significantly increase the secretion of IL-2 and IFN-gamma in doublejway MLR at the concentrations of 0.2-12.8 mg/L, but Gl-BSP had stronger effects than Gl-SP at the same concentrations. Both Gl-SP and Gl-BSP could increase the ratio of T-lymphocyte subpopulations in double-way MLR. At the concentrations of 0.2-12.8 mg/L or 3.2-12.8 mg/L, Gl-BSP demonstrated more significant activity in increasing the percentage of the CD4(+) or CD8(+) subset than Gl-SP. At the concentrations of 0.2-0.8 mg/L, the ratio of the CD4(+) and CD8(+) subset in the Gl-BSP treated group was higher than that of the Gl-SP treated group. CONCLUSION: Gl-SP and Gl-BSP have similar immunomodulatory effects in vitro, as though the immunomodulatory effects of Gl-BSP are stronger than that of Gl-SP.


Asunto(s)
Adyuvantes Inmunológicos/farmacología , Linfocitos/efectos de los fármacos , Macrófagos Peritoneales/efectos de los fármacos , Polisacáridos/farmacología , Reishi/química , Animales , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/inmunología , Ensayo de Inmunoadsorción Enzimática , Femenino , Citometría de Flujo , Interferón gamma/análisis , Interleucina-2/análisis , Linfocitos/inmunología , Linfocitos/metabolismo , Macrófagos Peritoneales/inmunología , Macrófagos Peritoneales/metabolismo , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Polisacáridos/aislamiento & purificación , Bazo/citología , Esporas Fúngicas/química , Linfocitos T Citotóxicos/efectos de los fármacos , Linfocitos T Citotóxicos/inmunología , Factor de Necrosis Tumoral alfa/análisis
14.
Front Pharmacol ; 3: 135, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22811667

RESUMEN

The antitumor and immunomodulatory activity of broken-spore of Ganodermalucidum polysaccharides (Gl-BSP) were investigated in vivo and in vitro. It was showed that Gl-BSP (50, 100, and 200 mg kg(-1)) exhibited antitumor effect against Sarcoma 180 (S180) in BALB/c mice. The Gl-BSP was not cytotoxicity in S180 cells and PG cells (human lung carcinoma cell) in vitro. However, serum from Gl-BSP-treated S180-bearing mice significantly inhibited S180 and PG cells proliferation in vitro. Moreover, Gl-BSP promoted the splenic lymphocyte proliferation induced by Con A or LPS, enhanced nature killer cell (NK cell) cytotoxic activity, augmented the percentage of neutral red phagocytosis by macrophages, and increased the percentage of the CD4(+) or CD8(+) subset in S180-bearing mice. The serum level of IFN-γ, TNF-α, and nitric oxide was increased by Gl-BSP. Gl-BSP also showed immunomodulatory activities in tumor-bearing mice. Furthermore, neutralization with anti-TNF-α and/or anti-IFN-γ significantly diminished growth inhibition induced by Gl-BSP-treated serum of S180-bearing mice in S180 or PG cells. These observations suggest that the antitumor activity of Gl-BSP may be mainly related to the activation of the immune response of the host organism by the stimulation of NK cells, T cells, and macrophages.

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