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1.
Cereb Cortex ; 34(4)2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38669008

RESUMEN

The COVID-19 pandemic has had profound but incompletely understood adverse effects on youth. To elucidate the role of brain circuits in how adolescents responded to the pandemic's stressors, we investigated their prepandemic organization as a predictor of mental/emotional health in the first ~15 months of the pandemic. We analyzed resting-state networks from n = 2,641 adolescents [median age (interquartile range) = 144.0 (13.0) months, 47.7% females] in the Adolescent Brain Cognitive Development study, and longitudinal assessments of mental health, stress, sadness, and positive affect, collected every 2 to 3 months from May 2020 to May 2021. Topological resilience and/or network strength predicted overall mental health, stress and sadness (but not positive affect), at multiple time points, but primarily in December 2020 and May 2021. Higher resilience of the salience network predicted better mental health in December 2020 (ß = 0.19, 95% CI = [0.06, 0.31], P = 0.01). Lower connectivity of left salience, reward, limbic, and prefrontal cortex and its thalamic, striatal, amygdala connections, predicted higher stress (ß = -0.46 to -0.20, CI = [-0.72, -0.07], P < 0.03). Lower bilateral robustness (higher fragility) and/or connectivity of these networks predicted higher sadness in December 2020 and May 2021 (ß = -0.514 to -0.19, CI = [-0.81, -0.05], P < 0.04). These findings suggest that the organization of brain circuits may have played a critical role in adolescent stress and mental/emotional health during the pandemic.


Asunto(s)
Encéfalo , COVID-19 , Imagen por Resonancia Magnética , Estrés Psicológico , Humanos , COVID-19/psicología , Adolescente , Femenino , Masculino , Estrés Psicológico/fisiopatología , Estrés Psicológico/psicología , Encéfalo/crecimiento & desarrollo , Encéfalo/diagnóstico por imagen , Resiliencia Psicológica , Emociones/fisiología , Red Nerviosa/diagnóstico por imagen , Red Nerviosa/crecimiento & desarrollo , Red Nerviosa/fisiología , Vías Nerviosas/fisiología , Vías Nerviosas/crecimiento & desarrollo , Salud Mental , Estudios Longitudinales , Desarrollo del Adolescente/fisiología , Niño
2.
Chemistry ; 30(13): e202303917, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38093171

RESUMEN

Aqueous zinc-ion batteries (ZIBs) have emerged as the most promising candidate for large-scale energy storage due to their inherent safety, environmental friendliness, and cost-effectiveness. Simultaneously, the utilization of organic electrode materials with renewable resources, environmental compatibility, and diverse structures has sparked a surge in research and development of aqueous Zn-organic batteries (ZOBs). A comprehensive review is warranted to systematically present recent advancements in design principles, synthesis techniques, energy storage mechanisms, and zinc-ion storage performance of organic cathodes. In this review article, we comprehensively summarize the energy storage mechanisms employed by aqueous ZOBs. Subsequently, we categorize organic cathode materials into small-molecule compounds and high-molecular polymers respectively. Novel polymer materials such as conjugated polymers (CPs), conjugated microporous polymers (CMPs), and covalent organic frameworks (COFs) are highlighted with an overview of molecular design strategies and structural optimization based on organic cathode materials aimed at enhancing the performance of aqueous ZOBs. Finally, we discuss the challenges faced by aqueous ZOBs along with future prospects to offer insights into their practical applications.

3.
Ecotoxicol Environ Saf ; 276: 116313, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38626602

RESUMEN

Wheat (Triticum aestivum L.) is a major foodstuff for over 40% of the world's population. However, hexavalent chromium [Cr(VI)] in contaminated soil significantly affects wheat production and its ecological environment. Streptomyces sp. HU2014 was first used to investigate the effects of Cr (VI) stress on wheat growth. We analyzed the Cr(VI) concentration, physicochemical properties of wheat and soil, total Cr content, and microbial community structures during their interactions. HU2014 reduced the toxicity of Cr(VI) and promoted wheat growth by increasing total nitrogen, nitrate nitrogen, total phosphorus, and Olsen-phosphorus in Cr(VI)-contaminated soil. These four soil variables had strong positive effects on two bacterial taxa, Proteobacteria and Bacteroidota, in the HU2014 treatments. In addition, the level of the dominant Proteobacteria positively correlated with the total Cr content in the soil. Among the fungal communities, which had weaker correlations with soil variables compared with bacterial communities, Ascomycota was the most abundant. Our findings suggest that HU2014 can promote the phytoremediation of Cr(VI)-contaminated soil.


Asunto(s)
Biodegradación Ambiental , Cromo , Rizosfera , Microbiología del Suelo , Contaminantes del Suelo , Streptomyces , Triticum , Cromo/toxicidad , Streptomyces/efectos de los fármacos , Triticum/crecimiento & desarrollo , Triticum/microbiología , Triticum/efectos de los fármacos , Contaminantes del Suelo/toxicidad , Suelo/química , Proteobacteria/efectos de los fármacos , Nitrógeno/metabolismo , Fósforo
4.
BMC Genomics ; 24(1): 277, 2023 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-37226137

RESUMEN

BACKGROUND: Macleaya cordata is a traditional medicinal herb, and it has high tolerance and accumulation ability to heavy metals, which make it a good candidate species for studying phytoremediation. The objectives of this study were to investigate response and tolerance of M. cordata to lead (Pb) toxicity based on comparative analysis of transcriptome and proteome. RESULTS: In this study, the seedlings of M. cordata cultured in Hoagland solution were treated with 100 µmol·L- 1 Pb for 1 day (Pb 1d) or 7 days (Pb 7d), subsequently leaves of M. cordata were taken for the determination of Pb accumulation and hydrogen peroxide production (H2O2), meanwhile a total number of 223 significantly differentially expressed genes (DEGs) and 296 differentially expressed proteins (DEPs) were screened between control and Pb treatments. The results showed leaves of M. cordata had a special mechanism to maintain Pb at an appropriate level. Firstly, some DEGs were iron (Fe) deficiency-induced transporters, for example, genes of vacuolar iron transporter and three ABC transporter I family numbers were upregulated by Pb, which can maintain Fe homeostasis in cytoplasm or chloroplast. In addition, five genes of calcium (Ca2+) binding proteins were downregulated in Pb 1d, which may regulate cytoplasmic Ca2+ concentration and H2O2 signaling pathway. On the other hand, the cysteine synthase upregulated, glutathione S-transferase downregulated and glutathione reductase downregulated in Pb 7d can cause reduced glutathione accumulation and decrease Pb detoxification in leaves. Furthermore, DEPs of eight chlorophyll a/b binding proteins, five ATPases and eight ribosomal proteins can play a pivotal role on chloroplast turnover and ATP metabolism. CONCLUSIONS: Our results suggest that the proteins involved in Fe homeostasis and chloroplast turnover in mesophyll cells may play key roles in tolerance of M. cordata to Pb. This study offers some novel insights into Pb tolerance mechanism of plants, and the potential valuable for environmental remediation of this important medicinal plant.


Asunto(s)
Peróxido de Hidrógeno , Plomo , Plomo/toxicidad , Clorofila A , Transportadoras de Casetes de Unión a ATP , Adenosina Trifosfatasas
5.
Neuroimage ; 284: 120459, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-37977408

RESUMEN

Metabolic, hormonal, autonomic and physiological rhythms may have a significant impact on cerebral hemodynamics and intrinsic brain synchronization measured with fMRI (the resting-state connectome). The impact of their characteristic time scales (hourly, circadian, seasonal), and consequently scan timing effects, on brain topology in inherently heterogeneous developing connectomes remains elusive. In a cohort of 4102 early adolescents with resting-state fMRI (median age = 120.0 months; 53.1 % females) from the Adolescent Brain Cognitive Development Study, this study investigated associations between scan time-of-day, time-of-week (school day vs weekend) and time-of-year (school year vs summer vacation) and topological properties of resting-state connectomes at multiple spatial scales. On average, participants were scanned around 2 pm, primarily during school days (60.9 %), and during the school year (74.6 %). Scan time-of-day was negatively correlated with multiple whole-brain, network-specific and regional topological properties (with the exception of a positive correlation with modularity), primarily of visual, dorsal attention, salience, frontoparietal control networks, and the basal ganglia. Being scanned during the weekend (vs a school day) was correlated with topological differences in the hippocampus and temporoparietal networks. Being scanned during the summer vacation (vs the school year) was consistently positively associated with multiple topological properties of bilateral visual, and to a lesser extent somatomotor, dorsal attention and temporoparietal networks. Time parameter interactions suggested that being scanned during the weekend and summer vacation enhanced the positive effects of being scanned in the morning. Time-of-day effects were overall small but spatially extensive, and time-of-week and time-of-year effects varied from small to large (Cohen's f ≤ 0.1, Cohen's d<0.82, p < 0.05). Together, these parameters were also positively correlated with temporal fMRI signal variability but only in the left hemisphere. Finally, confounding effects of scan time parameters on relationships between connectome properties and cognitive task performance were assessed using the ABCD neurocognitive battery. Although most relationships were unaffected by scan time parameters, their combined inclusion eliminated associations between properties of visual and somatomotor networks and performance in the Matrix Reasoning and Pattern Comparison Processing Speed tasks. Thus, scan time of day, week and year may impact measurements of adolescent brain's functional circuits, and should be accounted for in studies on their associations with cognitive performance, in order to reduce the probability of incorrect inference.


Asunto(s)
Conectoma , Femenino , Humanos , Adolescente , Niño , Masculino , Imagen por Resonancia Magnética , Encéfalo/fisiología , Cognición , Ganglios Basales , Red Nerviosa/fisiología
6.
Plant Dis ; 107(4): 1139-1150, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36190299

RESUMEN

Wheat sharp eyespot is a serious disease caused by the phytopathogens Rhizoctonia cerealis and R. solani. Some species in the genus Streptomyces have been identified as potential biocontrol agents against phytopathogens. In this investigation, the physiological, biochemical, phylogenetic, and genomic characteristics of strain HU2014 indicate that it is a novel Streptomyces sp. most closely related to Streptomyces albireticuli. Strain HU2014 exhibited strong antifungal activity against R. cerealis G11 and R. solani YL-3. Ultraperformance liquid chromatography-mass spectrometry on the four extracts from the extracellular filtrate of strain HU2014 identified 10 chemical constituents in the Natural Products Atlas with high match levels (more than 90%). In an antifungal efficiency test on wheat sharp eyespot, two extracts significantly reduced the lesion areas on bean leaves infected by R. solani YL-3. The drenching of wheat in pots with spore suspension of strain HU2014 demonstrated a control efficiency of 65.1% against R. cerealis G11 (compared with 66.9% when treated by a 30% hymexazol aqueous solution). Additionally, in vitro and pot experiments demonstrated that strain HU2014 can produce indoleacetic acid, siderophores, extracellular enzymes, and solubilized phosphate, and it can promote plant growth. We conclude that strain HU2014 could be a valuable microbial resource for growth promotion of wheat and biological control of wheat sharp eyespot.


Asunto(s)
Rhizoctonia , Streptomyces , Rhizoctonia/fisiología , Triticum/microbiología , Antifúngicos , Filogenia , Enfermedades de las Plantas/microbiología , Extractos Vegetales
7.
Angew Chem Int Ed Engl ; 62(24): e202303480, 2023 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-37041737

RESUMEN

The non-metal NH4 + carrier has attracted tremendous interests for aqueous energy storage owing to its light molar mass and fast diffusion in aqueous electrolytes. Previous study inferred that NH4 + ion storage in layered VOPO4 ⋅2 H2 O is impossible due to the removal of NH4 + from NH4 VOPO4 leads to a phase change inevitably. Herein, we update this cognition and demonstrated highly reversible intercalation/de-intercalation behavior of NH4 + in layered VOPO4 ⋅2 H2 O host. Satisfactory specific capacity of 154.6 mAh g-1 at 0.1 A g-1 and very stable discharge potential plateau at 0.4 V based on reference electrode was achieved in VOPO4 ⋅2 H2 O. A rocking-chair ammonium-ion full cell with the VOPO4 ⋅2 H2 O//2.0 M NH4 OTf//PTCDI configuration exhibited a specific capacity of 55 mAh g-1 , an average operating voltage of about 1.0 V and excellent long-term cycling stability over 500 cycles with a coulombic efficiency of ≈99 %. Theoretical DFT calculations suggest a unique crystal water substitution process by ammonium ion during the intercalation process. Our results provide new insight into the intercalation/de-intercalation of NH4 + ions in layered hydrated phosphates through crystal water enhancement effect.

8.
Hepatology ; 73(4): 1346-1364, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-32592194

RESUMEN

BACKGROUND AND AIMS: Nonalcoholic fatty liver disease (NAFLD) has been widely recognized as a precursor to metabolic complications. Elevated inflammation levels are predictive of NAFLD-associated metabolic disorder. Inactive rhomboid-like protein 2 (iRhom2) is regarded as a key regulator in inflammation. However, the precise mechanisms by which iRhom2-regulated inflammation promotes NAFLD progression remain to be elucidated. APPROACH AND RESULTS: Here, we report that insulin resistance, hepatic steatosis, and specific macrophage inflammatory activation are significantly alleviated in iRhom2-deficient (knockout [KO]) mice, but aggravated in iRhom2 overexpressing mice. We further show that, mechanistically, in response to a high-fat diet (HFD), iRhom2 KO mice and mice with iRhom2 deficiency in myeloid cells only showed less severe hepatic steatosis and insulin resistance than controls. Inversely, transplantation of bone marrow cells from healthy mice to iRhom2 KO mice expedited the severity of insulin resistance and hepatic dyslipidemia. Of note, in response to HFD, hepatic iRhom2 binds to mitogen-activated protein kinase kinase kinase 7 (MAP3K7) to facilitate MAP3K7 phosphorylation and nuclear factor kappa B cascade activation, thereby promoting the activation of c-Jun N-terminal kinase/insulin receptor substrate 1 signaling, but disturbing AKT/glycogen synthase kinase 3ß-associated insulin signaling. The iRhom2/MAP3K7 axis is essential for iRhom2-regulated liver steatosis. CONCLUSIONS: iRhom2 may represent a therapeutic target for the treatment of HFD-induced hepatic steatosis and insulin resistance.


Asunto(s)
Proteínas Portadoras/metabolismo , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Hígado/metabolismo , Quinasas Quinasa Quinasa PAM/metabolismo , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Activación Metabólica , Animales , Proteínas Portadoras/biosíntesis , Dieta Alta en Grasa/efectos adversos , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Hígado Graso/etiología , Hígado Graso/metabolismo , Hígado Graso/fisiopatología , Inflamación/metabolismo , Inflamación/fisiopatología , Resistencia a la Insulina/fisiología , Péptidos y Proteínas de Señalización Intracelular/biosíntesis , Hígado/fisiopatología , Macrófagos/metabolismo , Ratones Endogámicos C57BL , Ratones Noqueados , Enfermedad del Hígado Graso no Alcohólico/etiología , Enfermedad del Hígado Graso no Alcohólico/fisiopatología , Transducción de Señal
9.
Anticancer Drugs ; 33(1): e273-e285, 2022 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-34407055

RESUMEN

HMGA1 has been reported to be aberrantly expressed and correlate with the poor prognosis of many carcinomas. This study aimed to investigate the clinical significance and molecular mechanism of HMGA1 as a tumor-suppressing gene in hepatocellular carcinoma (HCC). Analysis of TCGA dataset by TANRIC website and R2 platform, we found that HMGA1 expression was significantly higher in HCC tissues compared to that in normal liver tissues and was associated with Edmondson grade. Patients with highly expressed HMGA1 had worse overall survival. Gene ontology enrichment analysis and Kyoto Encyclopedia of Genes and Genomes analysis showed the potential relationships between HMGA1 and other genes in HCC. We also demonstrated that the downregulation of HMGA1 dramatically suppressed the proliferation and migration of HCC cells. Furthermore, ectopic expression of HMGA1 blocked G0/G1 to S transition. Subsequent investigation characterized HMGA1 as a direct target of miR-195-5p, and miR-195-5p downregulation abrogated the effect of HMGA1 on HCC proliferation, migration, and cell cycle arrest. In addition, we also demonstrated that miR-195-5p downregulation abrogated the effect of HMGA1 on HCC growth in vivo. Taken together, our data provide strong evidence that HMGA1 promotes HCC and is negatively regulated by the tumor-suppressor, miR-195-5p.


Asunto(s)
Carcinoma Hepatocelular/genética , Proteína HMGA1a/genética , Neoplasias Hepáticas/genética , MicroARNs/genética , Animales , Carcinoma Hepatocelular/mortalidad , Carcinoma Hepatocelular/patología , Movimiento Celular/fisiología , Proliferación Celular/fisiología , Ontología de Genes , Genes Supresores de Tumor , Humanos , Neoplasias Hepáticas/mortalidad , Neoplasias Hepáticas/patología , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Clasificación del Tumor , Regulación hacia Arriba , Ensayos Antitumor por Modelo de Xenoinjerto
10.
Molecules ; 27(21)2022 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-36364306

RESUMEN

Ginkgo tea and ginkgo wine are two familiar Ginkgo biloba leaf extract (GBE) drinks in the form of dietary supplements (DS) used for healthcare in east Asia. Nevertheless, a comprehensive evaluation of their safety and efficacy is still lacking. In this study, GBE drinks were prepared from naturally newly senescent yellow leaves (YL) and green leaves (GL) in autumn. Their total flavonoids, antioxidant capacity and prescribed ingredients were investigated. In brief, the proportions of total flavonoids, total flavonol glycosides (TFs), total terpene trilactones (TTLs) and ginkgolic acids in the GBE drinks all did not meet the standards of worldwide pharmacopoeias. Specifically, the levels of TFs in the ginkgo tea prepared from YL were significantly higher than that prepared from GL. Further analyses revealed a substandard ratio of isorhamnetin/quercetin and an accumulation of leaf-age-related compounds, which were both unqualified. The proportions of specific TTLs varied between the ginkgo tea and ginkgo wine, although no significant differences were detected in terms of the total levels of TTLs. Noticeably, numerous biflavones and thousands of times over the limiting concentration of ginkgolic acids, including newly identified types, were only detected in ginkgo wine. Finally, the use of the GBE drinks as DSs was comprehensively evaluated according to the acceptable daily intake. This study showed the limited healthcare effects of GBE drinks despite their powerful antioxidant capacity.


Asunto(s)
Antioxidantes , Ginkgo biloba , Antioxidantes/farmacología , Antioxidantes/análisis , Extractos Vegetales/farmacología , Suplementos Dietéticos/análisis , Flavonoides/farmacología , Terpenos/análisis , , Hojas de la Planta/química
11.
Angew Chem Int Ed Engl ; 61(51): e202214244, 2022 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-36285465

RESUMEN

A novel poly(phenazine-alt-pyromellitic anhydride) (PPPA) has been successfully designed and synthesized via a condensation polymerization strategy as promising cathode material in organic zinc-ion batteries. Electrochemical quartz crystal microbalance (EQCM), FTIR and XPS characterizations verify a reversible Zn2+ -coordination mechanism in our PPPA cathode. Intriguingly, an ultrahigh Zn2+ diffusion coefficient of 1.2×10-7  cm2 s-1 was found in this large π-conjugated system, which is the highest one among all organic cathode materials for zinc-ion batteries. Theoretical calculations reveal the extended π-conjugated plane in our PPPA sample results in a significant reduction on energy gap, effectively accelerating intramolecular electron transfer during charge/discharge process. Our finding provides insights to achieve high zinc-ion transport kinetics by a design strategy on planar polymer system.

12.
Biochem Biophys Res Commun ; 524(1): 142-149, 2020 03 26.
Artículo en Inglés | MEDLINE | ID: mdl-31982140

RESUMEN

Nonalcoholic fatty liver disease (NAFLD) is featured by hepatic steatosis, insulin resistance, lipid deposition and inflammation. However, the pathogenic mechanism of NAFLD is still poorly understood. Dual-specificity phosphatase 16 (DUSP16), a c-Jun N-terminal kinase-specific phosphatase, has been reported to negatively modulate the mitogen-activated protein kinases (MAPKs) signaling, and it has never been investigated in NAFLD progression. In the study, we identified that DUSP16 could directly interact with TAK1 in human hepatocytes. DUSP16 knockdown in the isolated primary hepatocytes stimulated by palmitate (PA) showed accelerated lipid deposition and inflammatory response, along with the exacerbated activation of c-Jun NH2-terminal kinase (JNK), Transforming growth factor ß (TGF-ß)-activated kinase (TAK1) and nuclear factor-κB (NF-κB) signaling pathways; however, the opposite results were detected in PA-treated hepatocytes with DUSP16 over-expression. The in vivo experiments confirmed that DUSP16 knockout significantly aggravated the metabolic disorder and insulin resistance in high fat diet (HFD)-challenged mice. In addition, HFD-provoked hepatic lipid accumulation and inflammation were further promoted in mice with DUSP16 knockout through the same molecular mechanism as detected in vitro. Herein, these findings demonstrated that DUSP16 could directly interact with TAK1 and negatively regulate JNK signaling to alleviate metabolic stress-induced hepatic steatosis, and thus could be considered as a promising new molecular target for NAFLD treatment.


Asunto(s)
Dieta Alta en Grasa , Fosfatasas de Especificidad Dual/metabolismo , Dislipidemias/complicaciones , Inflamación/complicaciones , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Hígado/enzimología , Hígado/patología , Quinasas Quinasa Quinasa PAM/metabolismo , Fosfatasas de la Proteína Quinasa Activada por Mitógenos/metabolismo , Transducción de Señal , Animales , Línea Celular , Conducta Alimentaria , Hepatocitos/enzimología , Hepatocitos/patología , Humanos , Masculino , Ratones Endogámicos C57BL , Ratones Noqueados , Ácido Palmítico , Unión Proteica
13.
Small ; 16(35): e2000698, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32776405

RESUMEN

The realizing of high-performance rechargeable aqueous zinc-ion batteries (ZIBs) with high energy density and long cycling life is promising but still challenging due to the lack of suitable layered cathode materials. The work reports the excellent zinc-ion storage performance as-observed in few-layered ultrathin VSe2 nanosheets with a two-step Zn2+ intercalation/de-intercalation mechanism verified by ex situ X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) characterizations. The VSe2 nanosheets exhibit a discharge plateau at 1.0-0.7 V, a specific capacity of 131.8 mAh g-1 (at 0.1 A g-1 ), and a high energy density of 107.3 Wh kg-1 (at a power density of 81.2 W kg-1 ). More importantly, outstanding cycle stability (capacity retention of 80.8% after 500 cycles) without any activation process is achieved. Such a prominent cyclic stability should be attributed to its fast Zn2+ diffusion kinetics (DZn 2+  ≈ 10-8 cm-2 s-1 ) and robust structural/crystalline stability. Density functional theory (DFT) calculation further reveals a strong metallic characteristic and optimal zinc-ion diffusion pathway with a hopping energy barrier of 0.91 eV. The present finding implies that 2D ultrathin VSe2 is a very promising cathode material in ZIBs with remarkable battery performance superior to other layered transitional metal dichalcogenides.

14.
Langmuir ; 36(14): 3821-3825, 2020 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-32202117

RESUMEN

We investigated the interfacial instability of emulsion droplets via in situ measuring the oil/water interfacial tension (IFT) using the capillary suction method. The discrete phase of the oil-in-water emulsion contains a hydrophobic polymer (polystyrene, PS) and a fatty alcohol cosurfactant n-cetyl alcohol (CA) or n-octadecanol (OD), both of which were dissolved in an organic solvent (chloroform). The continuous phase is an aqueous solution of surfactant (sodium dodecyl sulfate, SDS). Upon removal of the organic solvent, the concentrations of CA and PS increase gradually, which induce a continual decrease of the IFT until the occurrence of interfacial instability. Micropipette tensiometry performed on an evaporating emulsion droplet reveals that interfacial instability is triggered when the IFT decreases close to ∼0.17 mN/m. As a result, micron particles with wrinkled surfaces can be obtained after the complete removal of the organic solvent. The effect of the initial concentration and alkyl chain length of the cosurfactant on the interfacial instability and surface roughness of the formed particles was studied. This study provides theoretical guidance for the preparation of micrometer-sized polymer particles with diverse morphologies via the interfacial instability of emulsion droplets.

15.
J Sep Sci ; 43(9-10): 1942-1966, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-31909566

RESUMEN

Capillary electrochromatography, which combined the high selectivity of high-performance liquid chromatography and the high separation efficiency of capillary electrophoresis, is an attractive separation tool. In this review, the developments on monolithic and open tubular capillary electrochromatography during 2017 to August 2019 are summarized. Considering the development of novel stationary phases is the most active research field in capillary electrochromatography, monolithic capillary electrochromatography is classified according to the polymer-based and hybrid monolithic columns, while open-tubular capillary electrochromatography is categorized by cyclodextrin, silica, polymer, nanomaterials, microporous materials, and biomaterials-based open tubular columns.

16.
Small ; 12(20): 2792-9, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-27062267

RESUMEN

Core-shell structured nanohybrids are currently of significant interest due to their synergetic properties and enhanced performances. However, the restriction of lattice mismatch remains a severe obstacle for heterogrowth of various core-shells with two distinct crystal structures. Herein, a controlled synthesis of lattice-mismatched core-shell TiO2 @MoS2 nano-onion heterostructures is successfully developed, using unilamellar Ti0.87 O2 nanosheets as the starting material and the subsequent epitaxial growth of MoS2 on TiO2 . The formation of these core-shell nano-onions is attributed to an amorphous layer-induced heterogrowth mechanism. The number of MoS2 layers can be well tuned from few to over ten layers, enabling layer-dependent synergistic effects. The core-shell TiO2 @MoS2 nano-onion heterostructures exhibit significantly enhanced energy storage performance as lithium-ion battery anodes. The approach has also been extended to other lattice-mismatched systems such as TiO2 @MoSe2 , thus suggesting a new strategy for the growth of well-designed lattice-mismatched core-shell structures.

17.
Bioorg Med Chem Lett ; 26(18): 4548-4551, 2016 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-27506558

RESUMEN

Three novel 6-N-substituted chitosan derivatives were designed and synthesised and characterized by FTIR and NMR. The degree of substitution was calculated by elemental analysis results. The antimicrobial activities of the target compounds were evaluated by twofold serial broth dilution method and poisoned food technique. The antifungal activities of 6-aminoethylamino-6-deoxy chitosan (3), 6-butylamino-6-deoxy chitosan (4) and 6-pyridyl-6-deoxy chitosan (5) were significantly increased against Rhizoctonia cerealis, Fusarium oxysporum and Botrytis cinerea, and the inhibition rate ranged from 22.48% to 63.56% at the concentration of 0.2mg/mL. The compound 3 had better antibacterial activities than chitosan, and the minimum inhibition concentration of which ranged between 6.25 and 25mg/L against gram-positive bacteria (Staphylococcus aureus, Bacillus subtilis and Bacillus anthracis) and gram-negative bacteria (Escherichia coli, Salmonella typhi). The antibacterial activities of 6-N-substituted chitosan tended to increase with the increase of the number of -NH2 group.


Asunto(s)
Antiinfecciosos/química , Antiinfecciosos/farmacología , Quitosano/química , Quitosano/farmacología , Antiinfecciosos/síntesis química , Bacterias/efectos de los fármacos , Quitosano/síntesis química , Hongos/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Espectroscopía de Protones por Resonancia Magnética , Espectroscopía Infrarroja por Transformada de Fourier
18.
Small ; 11(34): 4267-83, 2015 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-26121217

RESUMEN

Bimetallic oxide nickel cobaltite (NiCo2 O4 ) shows extensive potential for innovative photoelectronic and energetic materials owing to their distinctive physical and chemical properties. In this review, representative fabrications and applications of NiCo2 O4 nanostructures are outlined for photoelectronic conversion, catalysis, and energy storage, aiming to promote the development of NiCo2 O4 nanomaterials in these fields through an analysis and comparison of their diverse nanostructures. Firstly, a brief introduction of the spinel structures, properties, and morphologies of NiCo2 O4 nanomaterials are presented. Then, the advanced progress of NiCo2 O4 nanomaterials for both photoelectronic conversion and energy fields is summarized including such examples as solar cells, electrocatalysis, and lithium ion batteries. Finally, further prospects and promising developments of NiCo2 O4 nanomaterials in these significant fields are proposed.

19.
Small ; 11(13): 1531-6, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25384889

RESUMEN

The cathodoluminescence and optoelectronic properties based on an individual CdS/CdSe/CdS biaxial nanobelt are revealed in the present study. Both typical CdS and CdSe emissions are detected from as-grown CdS/CdSe/CdS nanobelts. The photodetector based on this nanobelt exhibits high sensitivity and excellent cycle stability. This opens a door to rational design of germanium chalcogenide compounds with unique optical properties.

20.
Mar Drugs ; 14(1): 4, 2015 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-26729137

RESUMEN

Three marine macroalgae, i.e., Grateloupia filicina, Ulva pertusa and Sargassum qingdaoense, were selected as the deputies of Rhodophyta, Chlorophyta and Ochrophyta for comparative analysis of the molecular structures and biological activities of sulfated polysaccharides (SP). The ratio of water-soluble polysaccharides, the monosaccharide composition and the sulfated contents of three extracted SPs were determined, and their structures were characterized by Fourier transformation infrared spectroscopy. In addition, biological activity analysis showed that all three SPs had immune-modulatory activity both in vitro and in vivo, and SPs from S. qingdaoense had the best effect. Further bioassays showed that three SPs could not only enhance the immunity level stimulated by inactivated avian influenza virus (AIV) in vivo but also significantly inhibited the activity of activated AIV (H9N2 subtype) in vitro. G. filicina SP exhibited the strongest anti-AIV activity. These results revealed the variations in structural features and bioactivities among three SPs and indicated the potential adjuvants for immune-enhancement and anti-AIV.


Asunto(s)
Antivirales/farmacología , Subtipo H9N2 del Virus de la Influenza A/efectos de los fármacos , Phaeophyceae , Polisacáridos/farmacología , Animales , Antivirales/química , Humanos , Ratones , Polisacáridos/química , Agua de Mar , Relación Estructura-Actividad
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