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1.
J Am Chem Soc ; 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38600631

RESUMEN

With impressive individual properties, carbon nanotubes (CNTs) show great potential in constructing high-performance fibers. However, the tensile strength of as-prepared carbon nanotube fibers (CNTFs) by floating catalyst chemical vapor deposition (FCCVD) is plagued by the weak intertube interaction between the essential CNTs. Here, we developed a chlorine (Cl)/water (H2O)-assisted length furtherance FCCVD (CALF-FCCVD) method to modulate the intertube interaction of CNTs and enhance the mechanical strength of macroscopic fibers. The CNTs acquired by the CALF-FCCVD method show an improvement of 731% in length compared to that by the conventional iron-based FCCVD system. Moreover, CNTFs prepared by CALF-FCCVD spinning exhibit a high tensile strength of 5.27 ± 0.27 GPa (4.62 ± 0.24 N/tex) and reach up to 5.61 GPa (4.92 N/tex), which outperforms most previously reported results. Experimental measurements and density functional theory calculations show that Cl and H2O play a crucial role in the furtherance of CNT growth. Cl released from the decomposition of methylene dichloride greatly accelerates the growth of the CNTs; H2O can remove amorphous carbon on the floating catalysts to extend their lifetime, which further modulates the growth kinetics and improves the purity of the as-prepared fibers. Our design of the CALF-FCCVD platform offers a powerful way to tune CNT growth kinetics in direct spinning toward high-strength CNTFs.

2.
Sci Adv ; 10(14): eadn6519, 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38569036

RESUMEN

Synthesizing single-walled carbon nanotubes (SWCNTs) with a narrow chirality distribution is essential for obtaining pure chirality materials through postgrowth sorting techniques. Using carbon monoxide chemical vapor deposition, we devise a ruthenium (Ru) catalyst supported by silica for the bulk production of SWCNTs containing only a few (n, m) species. The result is attributed to the limited carbon dissociation on the supported Ru clusters, favoring the growth of only small-diameter SWCNTs at comparable growth rates. The resulting materials expedite high-purity single chirality separation using gel chromatography, leading to unprecedented yields of 3.5% for (9, 1) and 5.2% for (9, 2) nanotubes, which surpass those separated from HiPco SWCNTs by two orders of magnitude. This work sheds light on the large-quantity synthesis of SWCNTs with enriched species beyond near-armchair ones for their high-yield separation.

3.
Mater Today Bio ; 25: 100969, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38318478

RESUMEN

Completely synthetic cell cultivation materials for human pluripotent stem cells (hPSCs) are important for the future clinical use of hPSC-derived cells. Currently, cell culture materials conjugated with extracellular matrix (ECM)-derived peptides are being prepared using only one specific integrin-targeting peptide. We designed dual peptide-conjugated hydrogels, for which each peptide was selected from different ECM sites: the laminin ß4 chain and fibronectin or vitronectin, which can target α6ß1 and α2ß1 or αVß5. hPSCs cultured on dual peptide-conjugated hydrogels, especially on hydrogels conjugated with peptides obtained from the laminin ß4 chain and vitronectin with a low peptide concentration of 200 µg/mL, showed high proliferation ability over the long term and differentiated into cells originating from 3 germ layers in vivo as well as a specific lineage of cardiac cells. The design of grafting peptides was also important, for which a joint segment and positive amino acids were added into the designed peptide. Because of the designed peptides on the hydrogels, only 200 µg/mL peptide solution was sufficient for grafting on the hydrogels, and the hydrogels supported hPSC cultures long-term; in contrast, in previous studies, greater than 1000 µg/mL peptide solution was needed for the grafting of peptides on cell culture materials.

4.
Clin Chem Lab Med ; 62(3): 562-571, 2024 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-37815315

RESUMEN

OBJECTIVES: Monocyte distribution width (MDW) is a quantitative measurement of monocyte anisocytosis and has been proposed as an efficient marker for early sepsis detection. This study aimed to assess the prognostic potential of MDW in septic patients. METHODS: In this study, a total of 252 adult septic patients were enrolled. Demographic, clinical, and laboratory finding including MDW and traditional inflammatory biomarkers detected at three time points (day 1, day 3 and day 6) after admission were collected and compared between 28-day survivors and non-survivors. Receiver operating characteristic (ROC) curves, Kaplan-Meier survival curve and Cox regression analyses were performed to assess and compare their predictive values. Group-based trajectory modeling was applied to identify MDW trajectory endotypes. Basic characteristics and 28-day outcomes were compared between the trajectories. RESULTS: ROC curve analysis showed that MDW levels measured on day 3 after admission (D3-MDW) had moderate prognostic value and was independently associated with 28-day mortality in patients with sepsis. A D3-MDW value of 26.20 allowed discrimination between survivors and non-survivors with a sensitivity of 77.8 % and a specificity of 67.6 %. However, the prognostic accuracy of D3-MDW was diminished in immune-compromised patients and patients who already received antibiotics before admission. Group-based trajectory modeling indicated that excessively elevated and delayed decreased MDW levels during the first week after admission inversely correlated with prognosis. CONCLUSIONS: MDW values detected on day 3 after admission and its kinetic change might be potential markers for predicting short-term outcome in adult septic patients.


Asunto(s)
Monocitos , Sepsis , Adulto , Humanos , Sepsis/diagnóstico , Biomarcadores , Pronóstico , Curva ROC
5.
Environ Sci Pollut Res Int ; 30(48): 105897-105911, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37718365

RESUMEN

Metal-organic frame (MOF) materials can effectively degrade organic pollutants, whereas the MOF is rapidly hydrolysed in water and has poor stability and low reusability. However, in the current advanced oxidation process (AOP) system, the removal effect of pollutants under alkaline condition is not ideal. In this study, a magnetic composite material derived from MOF was synthesised and used as a new catalyst for rapid degradation of tetrabromobisphenol A (TBBPA). Compared to precarbonisation, FeCo@GC formed a conductive graphite carbon skeleton, retained the complete rhombododecahedron structure, had a larger specific surface area and provided more active sites for peroxymonosulfate (PMS) activation. The target pollutant TBBPA (20 mg/L) was completely degraded within 30 min, and the mineralisation rate reached 40.98% in the FeCo@GC (150 mg/L) and PMS (1 mM) systems, owing to the synergistic interaction between Fe, Co and graphite carbon. The reactive oxygen species (ROS) involved in the reaction were determined to be SO4•-, ·OH, 1O2 and O2•- by electron paramagnetic resonance and free radical scavenging experiments, and the 1O2 played a dominant role. Based on the results of LC-MS analysis results, the main degradation pathways of TBBPA involve three mechanisms: the debromination reaction, hydroxylation and cleavage of the benzene ring. In addition, compared with previous AOP systems, FeCo@GC/PMS overcomes the disadvantage of poor degradation effect of TBPPA under alkaline conditions, has a wide range pH (3-11) application and has the best effect on TBBPA degradation under alkaline conditions. FeCo@GC has an excellent cycle performance, with a removal rate of re-calcined material of 88.52% after five cycles. Therefore, FeCo@GC can be used as a promising and efficient catalyst for removing environmental organic pollutants.


Asunto(s)
Contaminantes Ambientales , Grafito , Peróxidos/química , Carbono , Fenómenos Magnéticos , Concentración de Iones de Hidrógeno
6.
Nat Electron ; 6(8): 572-581, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37636241

RESUMEN

Graphene nanoribbons synthesized using bottom-up approaches can be structured with atomic precision, allowing their physical properties to be precisely controlled. For applications in quantum technology, the manipulation of single charges, spins or photons is required. However, achieving this at the level of single graphene nanoribbons is experimentally challenging due to the difficulty of contacting individual nanoribbons, particularly on-surface synthesized ones. Here we report the contacting and electrical characterization of on-surface synthesized graphene nanoribbons in a multigate device architecture using single-walled carbon nanotubes as the electrodes. The approach relies on the self-aligned nature of both nanotubes, which have diameters as small as 1 nm, and the nanoribbon growth on their respective growth substrates. The resulting nanoribbon-nanotube devices exhibit quantum transport phenomena-including Coulomb blockade, excited states of vibrational origin and Franck-Condon blockade-that indicate the contacting of individual graphene nanoribbons.

7.
Adv Mater ; : e2306129, 2023 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-37533318

RESUMEN

Poly(p-phenylene-benzimidazole-terephthalamide) (PBIA) fibers with excellent mechanical properties are widely used in fields that require impact-resistant materials such as ballistic protection and aerospace. The introduction of heterocycles in polymer chains increases their flexibility and makes it easier to optimize the fiber structure. However, the inadequate orientation of polymer chains is one of the main reasons for the large difference between the measured and theoretical mechanical properties of PBIA fibers. Herein, carbon nanotubes (CNTs) are selected as an orientation seed. Their structural features allow CNTs to orient during the spinning process, which can induce an orderly arrangement of polymers and improve the orientation of the fiber microstructure. To ensure the complete 1D topology of long CNTs (≈10 µm), PBIA is used as an efficient dispersant to overcome dispersion challenges. The p-CNT/PBIA fibers (10 µm single-walled carbon nanotube 0.025 wt%) exhibit an increase of 22% in tensile strength and 23% in elongation, with a maximum tensile strength of 7.01 ± 0.31 GPa and a reinforcement efficiency of 893.6. The artificial muscle fabricated using CNT/PBIA fibers exhibits a 34.8% contraction and a 25% lifting of a 2 kg dumbbell, providing a promising paradigm for high-performance organic fibers as high-load smart actuators.

8.
BMC Cancer ; 23(1): 516, 2023 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-37280594

RESUMEN

BACKGROUND: The aquaporin (AQP) family of proteins has been implicated in the proliferation and growth of gliomas. Expression of AQP8 is higher in human glioma tissues than in normal brain tissues and is positively correlated with the pathological grade of glioma, suggesting that this protein is also involved in the proliferation and growth of glioma. However, the mechanism by which AQP8 promotes the proliferation and growth of glioma remains unclear. This study aimed to investigate the mechanism and role of abnormal AQP8 expression in glioma development. METHODS: The dCas9-SAM and CRISPR/Cas9 techniques were used to construct viruses with overexpressed and knocked down AQP8, respectively, and infect A172 and U251 cell lines. The effects of AQP8 on the proliferation and growth of glioma and its mechanism via the intracellular reactive oxygen species (ROS) level were observed using cell clone, transwell, flow cytometry, Hoechst, western blotting, immunofluorescence, and real-time quantitative polymerase chain reaction assays. A nude mouse tumor model was also established. RESULTS: Overexpression of AQP8 resulted in an increased number of cell clones and cell proliferation, enhanced cell invasion and migration, decreased apoptosis and phosphatase and tensin homolog (PTEN) expression, and increased phosphorylated serine/threonine protein kinase (p-AKT) expression and ROS level, whereas the AQP8 knockdown groups showed opposite results. In the animal experiments, the AQP8 overexpression group had higher tumor volume and weight, whereas the AQP8 knockdown group had lower tumor volume and weight compared with those parameters measured in the control group. CONCLUSIONS: Our results preliminary suggest that AQP8 overexpression alters the ROS/PTEN/AKT signaling pathway, promoting the proliferation, migration, and invasion of gliomas. Therefore, AQP8 may be a potential therapeutic target in gliomas.


Asunto(s)
Glioma , Proteínas Proto-Oncogénicas c-akt , Animales , Humanos , Ratones , Apoptosis/genética , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica , Glioma/genética , Glioma/patología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Fosfohidrolasa PTEN/genética , Fosfohidrolasa PTEN/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal
9.
Adv Mater ; 35(35): e2303046, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37227940

RESUMEN

Photonic crystal fiber (PCF) embedded with functional materials has demonstrated diverse applications ranging from ultrafast lasers, optical communication to chemical sensors. Many efforts have been made to fabricating carbon nanotube (CNT) based optical fibers by ex situ transfer method; however, often suffer poor uniformity and coverage. Here, the direct growth of CNTs on the inner walls of PCFs by the chemical vapor deposition (CVD) method is reported. A two-step growth method is developed to control the narrow diameter distribution of CNTs to ensure desirable nanotube optical transitions. In the as-fabricated CNT- embedded fiber, third-harmonic generation (THG) has been enhanced by ≈15 times compared with flat CNT film on fused silica. A dual-wavelength all-fiber mode-locked ultrafast laser (≈1561 and ≈1064 nm) is further demonstrated by integrating the 1.36±0.15 nm-diameter CNTs into two kinds of photonic bandgap hollow core PCF (named HC-1550 and HC-1060) as saturable absorbers, using their S11 (≈0.7 eV) and S22 (≈1.2 eV) interband transition respectively. The fiber laser shows stable output of ≈10 mW, ≈800 fs pulse width, and ≈71 MHz repetition rate at 1561 nm wavelength. These results can enable the large-scale applications of CNTs in PCF-based optical devices.

10.
Ying Yong Sheng Tai Xue Bao ; 34(5): 1313-1319, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37236949

RESUMEN

The relationship between biodiversity and ecosystem stability is a hot topic in ecology. However, current studies focus mainly on aboveground system with plants, little attention has been paid to belowground system with soils. In this study, we constructed three soil suspensions with varying microbial diversity (100, 10-2, 10-6) by the dilution method and inoculated separately into agricultural Mollisols and Oxisols to examine the stability (indicated by resistance and resilience) of soil CO2 production and N2O emission to copper pollution and heat stress. Results showed that the stability of CO2 production in Mollisols was not influenced by microbial diversity loss, while the resistance and resilience of N2O emission in Mollisols were significantly decreased at the 10-6 diversity. In the Oxisols, the resistance and resilience of N2O emission to copper pollution and heat stress started to decrease even at the 10-2 diversity, and the stability of CO2 production decreased at the 10-6 diversity. These results suggested that both soil types and the identity of soil functions influenced the relationship between microbial diversity and the stability of function. It was concluded that soils with ample nutrients and resistant microbial communities tend to have higher functional stability, and that the fundamental soil functions (e.g., CO2 production) are more resistant and resilient than the specific soil functions (e.g., N2O emission) in response to environmental stress.


Asunto(s)
Ecosistema , Suelo , Dióxido de Carbono/análisis , Cobre , Agricultura , Microbiología del Suelo , Óxido Nitroso/análisis
11.
Front Public Health ; 11: 1137649, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37139384

RESUMEN

This retrospective analysis of fatal intoxication case autopsies was performed at Tongji Center for Medicolegal Expertise in Hubei (TCMEH) from 2009 to 2021 to obtain up-to-date information on intoxication cases. The objective was to describe important data about evolving patterns in intoxication occurrences, enhance public safety policies, and assist forensic examiners and police in more efficient handling of such cases. Analyses based on sex, age, topical exposure routes, toxic agents, and mode of death were performed using 217 records of intoxication cases collected from TCMEH as a sample, and the results were compared with reports previously published (from 1999 to 2008) from this institution. Deaths from intoxications occurred at a higher rate in males than in females and were most common among individuals aged 30-39 years. The most frequent method of exposure was oral ingestion. The causative agents of deadly intoxications have changed when compared to the data from the previous 10 years. For instance, deaths from amphetamine overdoses are becoming more prevalent gradually, whereas deaths due to carbon monoxide and rodenticide intoxication have declined dramatically. In 72 cases, pesticides continued to be the most frequent intoxication cause. A total of 60.4% of the deaths were accidental exposure. Men died from accidents at a higher rate than women, although women were more likely to commit suicide. Particular focus is needed on the use of succinylcholine, cyanide, and paraquat in homicides.


Asunto(s)
Plaguicidas , Masculino , Humanos , Femenino , Autopsia , Estudios Retrospectivos , Homicidio , China/epidemiología
12.
Molecules ; 28(6)2023 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-36985423

RESUMEN

Non-magnetic metal nanoparticles have been previously applied for the growth of single-walled carbon nanotubes (SWNTs). However, the activation mechanisms of non-magnetic metal catalysts and chirality distribution of synthesized SWNTs remain unclear. In this work, the activation mechanisms of non-magnetic metal palladium (Pd) particles supported by the magnesia carrier and thermodynamic stabilities of nucleated SWNTs with different (n, m) are evaluated by theoretical simulations. The electronic metal-support interaction between Pd and magnesia upshifts the d-band center of Pd, which promotes the chemisorption and dissociation of carbon precursor molecules on the Pd surface, making the activation of magnesia-supported non-magnetic Pd catalysts for SWNT growth possible. To verify the theoretical results, a porous magnesia supported Pd catalyst is developed for the bulk synthesis of SWNTs by chemical vapor deposition. The chirality distribution of Pd-grown SWNTs is understood by operating both Pd-SWNT interfacial formation energy and SWNT growth kinetics. This work not only helps to gain new insights into the activation of catalysts for growing SWNTs, but also extends the use of non-magnetic metal catalysts for bulk synthesis of SWNTs.

13.
Food Chem ; 404(Pt A): 134604, 2023 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-36270228

RESUMEN

Co-assembled foxtail millet (FP)-sodium casein (NaCas) nanocomplex and NaCas coated FP nanoparticles (NPs) were produced by using pH-cycle and anti-solvent methods, respectively. Subsequently, the effects of chitosan hydrochloride (CHC) coating on the particle size, surface charge and physicochemical stability of the two different FP/NaCas nanoparticles (NPs) were evaluated. With the addition of CHC, the particle size of NaCas coated FP NPs and co-assembled FP-NaCas nanocomplex significantly increased from 128.3 nm and 69.5 nm to 183.5 nm and 113.8 nm, respectively. The stability of the two kinds of CHC coated FP-based NPs to different pH values and varying ionic strengths was different due to their different NP structures. Using different fabrication formulations, co-assembled FP-NaCas NPs entrapped curcumin in relatively hydrophilic microenvironment and showed higher curcumin retention rate in comparison with NaCas coated FP NPs in terms of long-term storage stability. The results revealed that the produced CHC coated FP/NaCas nanocomplexes could be very beneficial in entrapping and delivering bioactive substances.


Asunto(s)
Quitosano , Curcumina , Nanopartículas , Setaria (Planta) , Curcumina/química , Caseínas/química , Quitosano/química , Prolaminas , Nanopartículas/química , Tamaño de la Partícula , Concentración de Iones de Hidrógeno , Portadores de Fármacos/química
14.
J Tradit Chin Med ; 42(5): 833-838, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36083493

RESUMEN

OBJECTIVE: To evaluate the diagnostic efficacy of Qisexingtai hand diagnostic method in the diagnosis of coronary artery disease (CAD). METHODS: This was an investigator-initiated, prospective, multi-center, cross-sectional study. All the participants from three hospitals in China had been diagnosed by both Qisexingtai hand diagnostic method and coronary angiography. We compared the two diagnostic methods to calculate the sensitivity, the specificity, the omission diagnostic rate, the mistaken diagnostic rate and accuracy in order to evaluate the diagnostic efficacy of Qisexingtai hand diagnostic method for CAD. RESULTS: A total of 326 subjects were enrolled, diagnosed by both Qisexingtai hand diagnostic method and coronary angiography. As a result, there were 166 positive cases according to Qisexingtai hand diagnostic method, and 131 positive cases according to coronary angiography. Compared with the results of coronary angiography, the sensitivity of Qisexingtai hand dia-gnostic method was 80.2%, the specificity was 68.7%, the omission diagnostic rate was 19.8%, the mistaken diagnostic rate was 31.3%, and the accuracy was 73.3%. Area under the receiver operating characteristic curve was estimated as 0.735 for all, and 0.718, 0.735, 0.783 for the three sub-centers. CONCLUSION: Qisexingtai hand diagnostic method with high accuracy and sensitivity has certain application value in the diagnosis of CAD.


Asunto(s)
Enfermedad de la Arteria Coronaria , China , Angiografía Coronaria/métodos , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Estudios Transversales , Humanos , Estudios Prospectivos
15.
Colloids Surf B Biointerfaces ; 217: 112685, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35797772

RESUMEN

In the last few decades, zein has been extensively studied owing to its wide commercial availability and the ability to self-assemble into nanosphere structure to encapsulate biologically active substances for targeted delivery. This work emphasized on comparing the encapsulation efficiency of hydrophobic active biomolecules and the physicochemical stability of composite nanoparticles (NPs) made up of zein- and foxtail millet prolamin (FP) -caseinate. Puerarin, resveratrol, diosmetin, and curcumin with various LogP values were selected as model drugs to study the single/co-encapsulation capacity, storage stability, and in vitro release profiles. Both LogP values (polarity) and specific structure are the main factors affecting the encapsulation efficiency. FP-based NPs could entrap more resveratrol, which may be related to the lower hydrophobic amino acid content of FP in comparison with that of zein. Co-encapsulation, in vitro release and long-term storage stability experiments confirmed that the model drugs were encapsulated in different NP regions mediated by polarity. Moreover, co-encapsulation changed the environment of curcumin from relatively polar microenvironment to hydrophobic regions. These hydrophobic regions retained significantly more curcumin during long-term storage stability. Overall, our results suggest that the hydrophobic amino acid composition of prolamin affects the encapsulation capacity. Various bioactives were encapsulated in the prolamin-based NPs via polarity mediation, and co-encapsulation could effectively retain the active molecules during storage.


Asunto(s)
Curcumina , Nanopartículas , Setaria (Planta) , Zeína , Aminoácidos , Curcumina/química , Nanopartículas/química , Tamaño de la Partícula , Prolaminas , Resveratrol , Zeína/química
16.
Neurobiol Learn Mem ; 194: 107662, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35870718

RESUMEN

The relationship between sleep and memory consolidation has not been fully revealed. The current study aimed to investigate how a brief afternoon nap contributed to the consolidation of declarative and procedural memory by exploring the relationship between sleep characteristics (i.e., the durations of sleep stages and slow oscillation, slow-wave activity, and spindle activity extracted from sleep) and task performance and the relationship between delta, theta, alpha, and beta bands extracted from wake during task performance and task performance. Twenty-three healthy young adults underwent a paired associates learning task and a sequential finger-tapping task with easy and difficult levels and were tested for memory performance before and after the intervention (i.e., an about 30-min nap or stay awake). Electroencephalogram (EEG) signals were continously recorded during the whole experiment. Results revealed that a short afternoon nap improved movement speed for the procedural memory task, regardless of the task difficulty, but unaffected the performance on the declarative memory task. Besides, the improvement in movement speed for the easy procedural memory task was positively correlated with slow-wave activity (SWA) during non-rapid-eye-movement (NREM) sleep but negatively correlated with slow oscillation and spindle activity during sleep stage 2 and NREM sleep, and the improvement in the difficult procedural memory task correlated positively with SWA during NREM sleep. Moreover, performance on the easy declarative and procedural memory tasks was negatively correlated with the relative power of alpha or theta; whereas the alpha band was positively correlated with the difficult declarative memory performance. These findings suggested that a brief afternoon nap with NREM sleep would benefit procedural memory consolidation but not declarative memory; such contribution of napping to memory consolidation would be either explained by the sleep characteristics or physiological arousal during performing tasks; task difficulty would moderate the relationship between the declarative memory performance and EEGs during task performance.


Asunto(s)
Consolidación de la Memoria , Sueño de Onda Lenta , Humanos , Consolidación de la Memoria/fisiología , Sueño/fisiología , Fases del Sueño/fisiología , Vigilia/fisiología , Adulto Joven
17.
Nano Lett ; 22(15): 6035-6047, 2022 08 10.
Artículo en Inglés | MEDLINE | ID: mdl-35852935

RESUMEN

The development of human society has set unprecedented demands for advanced fiber materials, such as lightweight and high-performance fibers for reinforcement of composite materials in frontier fields and functional and intelligent fibers in wearable electronics. Carbonene materials composed of sp2-hybridized carbon atoms have been demonstrated to be ideal building blocks for advanced fiber materials, which are referred to as carbonene fibers. Carbonene fibers that generally include pristine carbonene fibers, composite carbonene fibers, and carbonene-modified fibers hold great promise in transferring the extraordinary properties of nanoscale carbonene materials to macroscopic applications. Herein, we give a comprehensive discussion on the conception, classification, and design strategies of carbonene fibers and then summarize recent progress regarding the preparations and applications of carbonene fibers. Finally, we provide insights into developing lightweight, high-performance, functional, and intelligent carbonene fibers for next-generation fiber materials in the near future.


Asunto(s)
Carbono , Electrónica , Humanos
18.
Int J Psychophysiol ; 179: 21-29, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35753563

RESUMEN

Taking a short midday nap has been associated with higher alertness and better cognitive task performance. Yet, the mechanisms associated with nap-dependent performance enhancement are unclear. The current study was conducted to explore the impact of physiological arousal during cognitive task and sleep architecture during a pre-task nap on post-nap behavioral outcomes. A within-subjects design (N = 18) was employed, in which participants either took a nap or remained awake for 40 min during the post-lunch period. The psychomotor vigilance test (PVT) and n-back task were administered to assess sustained attention and working memory, respectively, with each task including one block of easy trials and one block of difficult trials. Results showed that a short midday nap improved sustained attention but not working memory. In addition, a midday nap induced lower physiological arousal during the performance on both cognitive tasks, with relatively higher delta and lower beta activity. The relative power of theta and alpha were positively correlated with performance on the easy PVT, whereas the alpha power was negatively correlated with performance on the difficult PVT, and the theta power was negatively correlated with reaction speed in the n-back task regardless of the task difficulty. Meanwhile, the shorter total sleep time and longer time of wake after sleep onset were associated with the faster overall reaction speed in PVT easy trials. These findings suggested that both changes in physiological arousal and sleep variables might account for changes in task performance after a short midday nap.


Asunto(s)
Desempeño Psicomotor , Sueño , Atención/fisiología , Humanos , Memoria a Corto Plazo/fisiología , Desempeño Psicomotor/fisiología , Tiempo de Reacción , Sueño/fisiología , Privación de Sueño , Vigilia/fisiología
19.
Peptides ; 152: 170774, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35219808

RESUMEN

BACKGROUND: Endoplasmic reticulum stress (ERS) plays an important role in the process of myocardial hypertrophy in diabetic cardiomyopathy (DCM). Irisin, a novel cytokine, has been found to protect against cardiac diastolic dysfunction in DCM. We aimed to investigate the role of irisin in cardiac hypertrophy and to elucidate the underlying mechanisms. METHODS: H9c2 cells were induced with 33 mM glucose to construct a cardiac hypertrophy cell model, which was then treated with irisin in the presence or absence of the ERS inducer tunicamycin (TM). The cell surface area was measured by FITC-phalloidin staining. The atrial natriuretic peptide levels were detected by an enzyme-linked immunosorbent assay. Furthermore, the expression of the ERS-related proteins, P-PERK, PERK, IRE1α and GRP78, was detected by western blotting. RESULTS: Irisin significantly reduced myocardial hypertrophy and suppressed high glucose (HG)-induced oxidative stress. Meanwhile, the protective effect of irisin on cardiomyoblasts was reversed by the ERS inducer, TM. Additionally, we detected ERS-associated signaling pathway proteins and found that irisin significantly reduced the protein expression levels of GRP78 and p-PERK/PERK. CONCLUSION: These results suggest that irisin ameliorates HG-induced cardiac hypertrophy by inhibiting ERS.


Asunto(s)
Estrés del Retículo Endoplásmico , Endorribonucleasas , Apoptosis , Cardiomegalia/inducido químicamente , Cardiomegalia/metabolismo , Endorribonucleasas/metabolismo , Endorribonucleasas/farmacología , Glucosa/metabolismo , Glucosa/toxicidad , Humanos , Miocitos Cardíacos/metabolismo , Proteínas Serina-Treonina Quinasas
20.
Phytochemistry ; 193: 112987, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34768188

RESUMEN

Picrasma quassioides, a member of the Simaroubaceae family, is the subject of research in numerous pharmacological and chemical studies. This plant mainly contains alkaloids, quassinoids and terpenoids. These molecules exhibit various pharmacological benefits, such as anti-inflammatory, anticancer, and anti-viral effects, on the cardiovascular system. Alkaloids make up the majority of these molecules. This review describes 127 alkaloid substances from P. quassioides. These alkaloids can be divided into the following classes: ß-carbolines, canthinones and alkaloid dimers. A compilation of their nuclear magnetic resonance spectroscopy data and possible biosynthetic pathways of these compounds and the pharmacological effects of P. quassioides are also included.


Asunto(s)
Alcaloides , Picrasma , Alcaloides/farmacología , Vías Biosintéticas , Espectroscopía de Resonancia Magnética , Estructura Molecular
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