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1.
J Am Chem Soc ; 146(11): 7332-7340, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38335733

RESUMO

The unstable electrode-electrolyte interface and the narrow electrochemical window of normal electrolytes hinder the potential application of high-voltage sodium metal batteries. These problems are actually related to the solvation structure of the electrolyte, which is determined by the competition between cations coordinated with anions or solvent molecules. Herein, we design an electrolyte incorporating ethyl (2,2,2-trifluoroethyl) carbonate and fluoroethylene carbonate, which facilitates a pronounced level of cation-anion coordination within the solvation sheath by enthalpy changes to reduce the overall coordination of cation-solvents and increase sensitivity to salt concentration. Such an electrolyte regulated by competitive coordination leads to highly reversible sodium plating/stripping with extended cycle life and a high Coulombic efficiency of 98.0%, which is the highest reported so far in Na||Cu cells with ester-based electrolytes. Moreover, 4.5 V high-voltage Na||Na3V2(PO4)2F3 cells exhibit a high rate capability up to 20 C and an impressive cycling stability with an 87.1% capacity retention after 250 cycles with limited Na. The proposed strategy of solvation structure modification by regulating the competitive coordination of the cation provides a new direction to achieve stable sodium metal batteries with high energy density and can be further extended to other battery systems by controlling enthalpy changes of the solvation structure.

2.
Stat Med ; 43(4): 674-688, 2024 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-38043523

RESUMO

Measures of substance concentration in urine, serum or other biological matrices often have an assay limit of detection. When concentration levels fall below the limit, exact measures cannot be obtained, and thus are left censored. The problem becomes more challenging when the censored data come from heterogeneous populations consisting of exposed and non-exposed subjects. If the censored data come from non-exposed subjects, their measures are always zero and hence censored, forming a latent class governed by a distinct censoring mechanism compared with the exposed subjects. The exposed group's censored measurements are always greater than zero, but less than the detection limit. It is very often that the exposed and non-exposed subjects may have different disease traits or different relationships with outcomes of interest, so we need to disentangle the two different populations for valid inference. In this article, we aim to fill the methodological gaps in the literature by developing a novel joint modeling approach to not only address the censoring issue in predictors, but also untangle different relationships of exposed and non-exposed subjects with the outcome. Simulation studies are performed to assess the numerical performance of our proposed approach when the sample size is small to moderate. The joint modeling approach is also applied to examine associations between plasma metabolites and blood pressure in Bogalusa Heart Study, and identify new metabolites that are highly associated with blood pressure.


Assuntos
Modelos Estatísticos , Humanos , Limite de Detecção , Simulação por Computador , Estudos Longitudinais
3.
Stat Med ; 43(1): 102-124, 2024 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-37921025

RESUMO

Human microbiome research has gained increasing importance due to its critical roles in comprehending human health and disease. Within the realm of microbiome research, the data generated often involves operational taxonomic unit counts, which can frequently present challenges such as over-dispersion and zero-inflation. To address dispersion-related concerns, the generalized Poisson model offers a flexible solution, effectively handling data characterized by over-dispersion, equi-dispersion, and under-dispersion. Furthermore, the realm of zero-inflated generalized Poisson models provides a strategic avenue to simultaneously tackle both over-dispersion and zero-inflation. The phenomenon of zero-inflation frequently stems from the heterogeneous nature of study populations. It emerges when specific microbial taxa fail to thrive in the microbial community of certain subjects, consequently resulting in a consistent count of zeros for these individuals. This subset of subjects represents a latent class, where their zeros originate from the genuine absence of the microbial taxa. In this paper, we introduce a novel testing methodology designed to uncover such latent classes within generalized Poisson regression models. We establish a closed-form test statistic and deduce its asymptotic distribution based on estimating equations. To assess its efficacy, we conduct an extensive array of simulation studies, and further apply the test to detect latent classes in human gut microbiome data from the Bogalusa Heart Study.


Assuntos
Microbioma Gastrointestinal , Microbiota , Humanos , Modelos Estatísticos , Simulação por Computador , Estudos Longitudinais , Distribuição de Poisson
4.
BMC Psychiatry ; 24(1): 146, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38383298

RESUMO

BACKGROUND: To investigate the incidence of depression in middle-aged and elderly patients with diabetes in China and the influencing factors to provide a theoretical basis to improve the mental health of middle-aged and elderly patients with diabetes and formulate prevention, control, and intervention strategies. METHODS: The sample of this study was obtained from the China Health and Aging Tracking Survey (CHARLS) 2018 survey data, and middle-aged and older patients with diabetes(responding "Yes" to the questionnaire: "Have you ever been told by a doctor that you have diabetes or elevated blood glucose [including abnormal glucose tolerance and elevated fasting glucose]?") aged ≥ 45 years were selected as study subjects (n = 2,613 ). Depressive symptoms of the study subjects were determined using the simplified version of the Depression Scale for Epidemiological Surveys scores(a score ≥ 10 was defined as depression), influence factors were analyzed using binary logistic regression, and proportion of depressive symptoms was standardized using the sex ratio of the seventh census. RESULTS: Among the 2,613 middle-aged and elderly patients with diabetes, 1782 (68.2%) had depressive symptoms and 831 (31.8%) had no depressive symptoms. There were 481 (27.0%) patients aged 45-59 years, 978 (54.9%) aged 60-74 years, and 323 (18.1%) aged ≥ 75 years. The depression rate among middle-aged and elderly Chinese patients with diabetes after standardization correction was 67.5%. Binary logistic regression results showed that age, education level, life satisfaction, marital satisfaction, self-rated health grade, somatic pain, visual impairment, physical disability, and the presence of comorbid chronic diseases were factors that influenced the onset of depression in middle-aged and elderly Chinese patients with diabetes (P < 0.05). CONCLUSION: According to a survey analysis of the CHARLS 2018 data, depression is influenced by a combination of factors among middle-aged and elderly patients with diabetes in China. Therefore, for this population, targeted prevention and control should be carried out for key populations, such as middle-aged and elderly people, poor physical health, and low life satisfaction and marital satisfaction, from various dimensions (e.g., demographic and sociological factors, physical health status, and life satisfaction and marital satisfaction).


Assuntos
Depressão , Diabetes Mellitus , Idoso , Pessoa de Meia-Idade , Humanos , Depressão/epidemiologia , Depressão/psicologia , Incidência , Diabetes Mellitus/epidemiologia , Envelhecimento , Glucose , China/epidemiologia , Estudos Longitudinais
5.
Small ; 19(24): e2206000, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36892152

RESUMO

Li metal anode is promising to achieve high-energy-density battery. However, it has rapid capacity fading due to the generation of inactive Li (dead Li), especially at high current density. This study reveals that the random distribution of Li nuclei leads to large uncertainty for the further growth behavior on Cu foil. Here, periodical regulation of Li nucleation sites on Cu foil by ordered lithiophilic micro-grooves is proposed to precisely manipulate the Li deposition morphology. The management of Li deposits in the lithiophilic grooves can induce high pressure on the Li particles, leading to the formation of dense Li structure and smooth surface without dendrite growth. Li deposits comprising tightly packed large Li particles largely reduce the side reaction and the generation of isolated metallic Li at high current density. Less dead Li accumulating on the substrate significantly prolongs the cycling life of full cells with limited Li inventory. The precise manipulation of the Li deposition on Cu is promising for high-energy and stable Li metal batteries.

6.
Int J Cosmet Sci ; 45(4): 426-443, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36896776

RESUMO

Sweating is the human body's thermoregulation system but also results in unpleasant body odour which can diminish the self-confidence of people. There has been continued research in finding solutions to reduce both sweating and body odour. Sweating is a result of increased sweat flow and malodour results from certain bacteria and ecological factors such as eating habits. Research on deodorant development focuses on inhibiting the growth of malodour-forming bacteria using antimicrobial agents, whereas research on antiperspirant synthesis focuses on technologies reducing the sweat flow, which not only reduces body odour but also improves people's appearance. Antiperspirant's technology is based on the use of aluminium salts which can form a gel plug at sweat pores, obstructing the sweat fluid from arising onto the skin surface. In this paper, we perform a systematic review on the recent progress in the development of novel antiperspirant and deodorant active ingredients that are alcohol-free, paraben-free, and naturally derived. Several studies have been reported on the alternative class of actives that can potentially be used for antiperspirant and body odour treatment including deodorizing fabric, bacterial, and plant extracts. However, a significant challenge is to understand how the gel-plugs of antiperspirant actives are formed in sweat pores and how to deliver long-lasting antiperspirant and deodorant benefits.


La transpiration est le système de thermorégulation de l'organisme, mais elle entraîne également une odeur corporelle désagréable qui peut diminuer la confiance en soi. Des nombreuses recherches ont été menées afin de trouver des solutions pour réduire à la fois la transpiration et l'odeur corporelle. La transpiration est le résultat de l'augmentation du flux de sueur, et les mauvaises odeurs sont dues à certaines bactéries et à certains facteurs écologiques tels que les habitudes alimentaires. Les recherches sur le développement des déodorants se concentrent sur l'inhibition de la croissance des bactéries responsables des mauvaises odeurs à l'aide d'agents antimicrobiens, tandis que les recherches sur la synthèse des anti-transpirants se concentrent sur les technologies diminuant le flux de sueur, ce qui réduire non seulement les odeurs corporelles, mais améliore également l'apparence des personnes. La technologie des anti-transpirants repose sur l'utilisation de sels d'aluminium qui peuvent former un bouchon de gel au niveau des pores sudoripares, empêchant le liquide sudoral d'apparaître à la surface de la peau. Dans cet article, nous effectuons une revue systématique des progrès récents réalisés dans le développement de nouveaux principes actifs anti-transpirants et déodorants qui sont sans alcool, sans parabène et d'origine naturelle. Plusieurs études ont été rapportées sur la classe alternative de principes actifs qui peuvent potentiellement être utilisés pour le traitement anti-transpirant et des odeurs corporelles, y compris les tissus désodorisants, les bactéries et les extraits végétaux. Cependant, un défi important consiste à comprendre comment les bouchons de gel des actifs anti-transpirants se forment au niveau des pores sudoripares, et comment offrir des effets anti-transpirants et déodorants durables.


Assuntos
Antiperspirantes , Desodorantes , Humanos , Antiperspirantes/farmacologia , Desodorantes/farmacologia , Odor Corporal , Sudorese , Glândulas Sudoríparas
7.
Geriatr Nurs ; 51: 136-142, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36940508

RESUMO

OBJECTIVE: The aim of this study was to investigate the level of diabetes self-management ability in older patients with type 2 diabetes and analyse its relationship with patient activation. Besides, the mediating effect of self-efficacy on the relationship between the two was assessed in the study. METHODS: Using a cross-sectional design, 200 elderly patients with type 2 diabetes were recruited from the community of Yangzhou, China. The Patient Activation Measure (PAM), The Self-efficacy for Diabetes (SED), and The Summary of Diabetes Self-Care Activities Measure (SDSCA) were used in the questionnaires. Data analysis was performed using SPSS 27.0 and PROCESS macro. RESULTS: Pearson correlation analysis revealed a significant positive correlation (p< 0.01) between diabetes self-management ability and patient activation (r=0.312) and self-efficacy (r=0.367). Self-efficacy partially mediated the effect between patient activation and self-management ability in older patients with type 2 diabetes, and the mediating effect accounted for 49.33% of the total effect (p< 0.001). CONCLUSIONS: Older patients with type 2 diabetes in the community have a moderate level of self-management ability. Patient activation can improve patients' self-management ability through self-efficacy.


Assuntos
Diabetes Mellitus Tipo 2 , Autogestão , Humanos , Idoso , Diabetes Mellitus Tipo 2/terapia , Autoeficácia , Participação do Paciente , Estudos Transversais , Inquéritos e Questionários , Autocuidado
8.
Eur J Vasc Endovasc Surg ; 61(4): 648-655, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33441270

RESUMO

OBJECTIVE: The aim of this study was to observe the spatial distribution and dynamic changes of matrix metalloproteinase (MMP)-2, MMP-9, and collagen in in stent restenosis (ISR) and to explore their influence on ISR. METHODS: Sixty Z type stents were implanted into the common iliac arteries of minipigs, which were divided into 10 groups (six in each group) according to euthanasia time (6 hours, and 1, 3, 7, 14, 28, 56, 84, 168, and 336 days). After the samples were harvested, haematoxylin and eosin staining, immunohistochemical staining, Western blotting, and Picrosirius red staining were performed for all groups. RESULTS: ISR occurred in all six minipigs in the 56 day group (percentage diameter stenosis range 71.6%-79.2%, mean ± standard deviation 75.6% ± 2.5%). The percentage diameter stenosis decreased to 38.3% ± 2.7% at 336 days (p < .001). Immunohistochemical staining showed that MMP-2 and MMP-9 were strongly stained near the internal elastic lamina or in the damaged parts of the intima, around the struts and neointimal lumen surface in the ISR process. The expression of MMP-2 and MMP-9 at 56 days was significantly lower compared with their peaks (seven days and one day [p < .001; p = .002], respectively). At 56 days, the collagen content reached its maximum (mean integrated optical density range 0.73-0.92, mean ± standard deviation 0.82 ± 0.09). From the 14 day group to the 336 day group, mature collagen in neointima was correlated negatively with MMP-2 (γ(36) = -0.816; p < .001) and MMP-9 expression (γ(36) = -0.853; p < .001). During the neointimal regression period, new collagen in neointima was positively correlated with MMP-2 (γ(24) = 0.683; p < .001) and MMP-9 (γ(24) = 0.873; p < .001). CONCLUSION: This study has demonstrated the spatial distribution of and dynamic changes in MMP-2, MMP-9, and collagen in ISR by simulating the process of neointima from generation to regression after stent implantation. When ISR occurred, MMP-2 and MMP-9 expression decreased and collagen content reached its maximum, which might contribute to ISR.


Assuntos
Colágeno/metabolismo , Procedimentos Endovasculares/instrumentação , Artéria Ilíaca/enzimologia , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Remodelação Vascular , Animais , Procedimentos Endovasculares/efeitos adversos , Artéria Ilíaca/patologia , Modelos Animais , Neointima , Stents , Suínos , Porco Miniatura , Fatores de Tempo , Regulação para Cima
9.
Inorg Chem ; 60(13): 10006-10011, 2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-34165953

RESUMO

The first strontium fluoroaluminoborate SrAlB3O6F2 was synthesized. Interestingly, it exhibits a two-dimensional warped layer composed of the [Al2B6O14F4] fundamental building units, which are first identified in borates. The experimental results indicate that SrAlB3O6F2 has a short ultraviolet cutoff edge (<200 nm) and large birefringence (0.075@546 nm), which are further verified by theoretical calculation. Thus, SrAlB3O6F2 can be used as the deep-ultraviolet birefringence material.

10.
Med Sci Monit ; 26: e922556, 2020 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-32214058

RESUMO

BACKGROUND The aim of this study was to compare changes in the extracellular matrix after implantation of a stent that elutes a matrix metalloproteinase (MMP) inhibitor (GM6001); and to determine the effects of the GM6001-eluting stent upon prevention of in-stent restenosis (ISR). MATERIAL AND METHODS We included 48 Guangxi Bama mini-pigs in this study. A GM6001-eluting stent was placed in one iliac artery and a stent that did not elute GM6001 was placed in the contralateral iliac artery. The iliac arteries were removed at 6 hours as well as 1, 7, 14, 56, 84, and 336 days after stent placement. Arteries were analyzed for morphometry, gelatinase content, different phenotypes of vascular smooth muscle cells (VSMCs), collagen content, apoptotic rate, and cell density. RESULTS The vascular lumen areas of the GM6001 group were significantly increased and the neointimal areas were significantly reduced compared with the control group from the 7 days to the 336 days. In the 2 groups, expression of MMP-2 and MMP-9 peaked simultaneously, but GM6001-eluting stents inhibited expression of MMP-2 and MMP-9 in the vascular media and neointima (especially around the struts) significantly. In the GM6001 group, expression of tissue inhibitor of matrix metalloproteinase (TIMP)-1, TIMP-2, myosin heavy chain 10 (MYH-10, marker of the proliferative phenotype of VSMCs), collagen content, percentage of apoptotic cells, and cell density were also decreased significantly compared with those in the control group. CONCLUSIONS Use of GM6001-eluting stents resulted in persistent and potent inhibition of intimal hyperplasia, an increase in luminal area, and no obvious thrombosis in the arteries of the mini-pigs.


Assuntos
Reestenose Coronária/tratamento farmacológico , Stents Farmacológicos , Inibidores de Metaloproteinases de Matriz/uso terapêutico , Animais , Apoptose , Colágeno/metabolismo , Reestenose Coronária/complicações , Reestenose Coronária/patologia , Feminino , Masculino , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Cadeias Pesadas de Miosina/metabolismo , Neointima/complicações , Neointima/patologia , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Suínos , Porco Miniatura , Fatores de Tempo , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Inibidor Tecidual de Metaloproteinase-2/metabolismo
11.
Soft Matter ; 15(8): 1704-1715, 2019 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-30724947

RESUMO

Peptide-based hydrogels have been proven to be preeminent biomedical materials due to their high water content, tunable mechanical stability, great biocompatibility and excellent injectability. The ability of peptide-based hydrogels to provide extracellular matrix-mimicking environments opens up opportunities for their biomedical applications in fields such as drug delivery, tissue engineering, and wound healing. In this review, we first describe several methods commonly used for the fabrication of robust peptide-based hydrogels, including spontaneous hydrogelation, enzyme-controlled hydrogelation and cross-linking-enhanced hydrogelation. We then introduce some representative studies on their applications in drug delivery and antitumor therapy, antimicrobial and wound healing materials, and 3D bioprinting and tissue engineering. We hope that this review facilitates the advances of hydrogels in biomedical applications.


Assuntos
Materiais Biocompatíveis/química , Hidrogéis/química , Peptídeos/química , Humanos
12.
Small ; 12(19): 2575-9, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27028848

RESUMO

The formation of ultralong peptide crystalline nanobelts using a solvothermal approach from a di-phenylalanine gel within 10 min, where the self-assembly process is accelerated by several orders of magnitude compared with the month-long glutaraldehyde induction method previously reported, has been demonstrated. The solvothermal treatment can facilitate the phase separation of di-phenylalanine gels while speeding up the kinetics of the intramolecular cyclization reaction and concomitant crystallization. Moreover, the modulation effect of formaldehyde as an additive is revealed, and that a small amount of formaldehyde leads to thicker crystalline platelets capable of curved optical waveguiding that can potentially be applied in advanced bio-optical and optoelectronic devices, a rare feat with peptide-based crystals.


Assuntos
Nanopartículas/química , Nanopartículas/ultraestrutura , Fenilalanina/química , Refratometria/métodos , Solventes/química , Ressonância de Plasmônio de Superfície/métodos , Sítios de Ligação , Cristalização/métodos , Luz , Teste de Materiais , Peso Molecular , Tamanho da Partícula , Peptídeos/química , Ligação Proteica , Espalhamento de Radiação , Temperatura
13.
Small ; 10(2): 285-93, 2014 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-23913836

RESUMO

Uniformly-sized, nanostructured peptide microparticles are generated by exploiting the ability of enzymes to serve (i) as catalysts, to control self-assembly within monodisperse, surfactant-stabilized water-in-oil microdroplets, and (ii) as destabilizers of emulsion interfaces, to enable facile transfer of the produced microparticles to water. This approach combines the advantages of biocatalytic self-assembly with the compartmentalization properties enabled by droplet microfluidics. Firstly, using microfluidic techniques, precursors of self-assembling peptide derivatives and enzymes are mixed in the microdroplets which upon catalytic conversion undergo molecular self-assembly into peptide particles, depending on the chemical nature of the precursors. Due to their amphiphilic nature, enzymes adsorb at the water-surfactant-oil interface of the droplets, inducing the transfer of peptide microparticles from the oil to the aqueous phase. Ultimately, through washing steps, enzymes can be removed from the microparticles which results in uniformely-sized particles composed of nanostructured aromatic peptide amphiphiles.


Assuntos
Biocatálise , Microfluídica/métodos , Nanoestruturas , Peptídeos/química , Adsorção , Microscopia Eletrônica de Varredura , Microscopia de Fluorescência , Monoéster Fosfórico Hidrolases/química , Termolisina/química
14.
Langmuir ; 30(25): 7576-84, 2014 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-24911955

RESUMO

We demonstrate the self-assembly of bola-amphiphile-type conjugates of dipeptides and perylene bisimide (PBI) in water and other polar solvents. Depending on the nature of the peptide used (glycine-tyrosine, GY, or glycine-aspartic acid, GD), the balance between H-bonding and aromatic stacking can be tailored. In aqueous buffer, PBI-[GY]2 forms chiral nanofibers, resulting in the formation of a hydrogel, while for PBI-[GD]2 achiral spherical aggregates are formed, demonstrating that the peptide sequence has a profound effect on the structure formed. In water and a range of other polar solvents, self-assembly of these two PBI-peptides conjugates results in different nanostructures with highly tunable fluorescence performance depending on the peptide sequence employed, e.g., fluorescent emission and quantum yield. Organogels are formed for the PBI-[GD]2 derivative in DMF and DMSO while PBI-[GY]2 gels in DMF. To the best of our knowledge, this is the first successful strategy for using short peptides, specifically, their sequence/structure relationships, to manipulate the PBI nanostructure and consequent optical properties. The combination of controlled self-assembly, varied optical properties, and formation of aqueous and organic gel-phase materials may facilitate the design of devices for various applications related to light harvesting and sensing.


Assuntos
Imidas/química , Peptídeos/química , Perileno/análogos & derivados , Solventes/química , Água/química , Perileno/química
15.
World Neurosurg ; 185: e603-e611, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38395354

RESUMO

OBJECTIVE: To analyze the mediating effects of caregiver illness uncertainty and psychological resilience in caregiver burden and readiness in patients with moderate-to-severe traumatic brain injuries (TBIs). This can help improve caregiver readiness in patients with moderate-to-severe TBIs. METHODS: A purposive sampling method was used to recruit patients with moderate-to-severe TBIs, and their caregivers, who were hospitalized in the Department of Neurosurgery of the Affiliated Hospital of Yangzhou University between October 2022 and August 2023. The Zarit Caregiver Burden Interview, Mishel Uncertainty In Scale for Family Member, Connor-Davidson Resilience Scale, and Caregivers Preparedness Scale, as well as general information questionnaire, were used to conduct the survey. RESULTS: Caregiver readiness correlated with caregiver burden, illness uncertainty, and psychological resilience in patients with moderate-to-severe TBI (P < 0.01). Caregiver readiness was not only directly affected by caregiver burden (95% confidence interval: -0.510, -0.196) but was also affected through the chain mediation of illness uncertainty and psychological resilience (95% confidence interval: -0.146, -0.011). CONCLUSIONS: Caregiver burden in patients with moderate-to-severe TBI influences caregiver readiness levels and is mediated by illness uncertainty and psychological resilience. By improving caregivers' illness uncertainty and increasing their psychological resilience, the impact of low caregiver readiness caused by high caregiver burden could be reduced.


Assuntos
Lesões Encefálicas Traumáticas , Sobrecarga do Cuidador , Cuidadores , Resiliência Psicológica , Humanos , Lesões Encefálicas Traumáticas/psicologia , Masculino , Feminino , Incerteza , Adulto , Pessoa de Meia-Idade , Cuidadores/psicologia , Sobrecarga do Cuidador/psicologia , Adulto Jovem , Idoso , Inquéritos e Questionários
16.
Adv Healthc Mater ; 13(4): e2302180, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37985965

RESUMO

The nature of the hydrogel scaffold mimicking extracellular matrix plays a crucial role in tissue engineering like skeletal muscle repair. Herein, an anisotropic and conductive hydrogel scaffold is fabricated using gelatin methacryloyl (GelMA) as the matrix hydrogel and silver nanowire (AgNW) as the conductive dopant, through a directional freezing technique for muscle defect repair. The scaffold has an anisotropic structure composed of a directional longitudinal section and a honeycomb cross-section, with high mechanical strength of 10.5 kPa and excellent conductivity of 0.26 S m-1 . These properties are similar to native muscle extracellular matrix (ECM) and allow for cell orientation under the guidance of contact cues and electrical stimulation synergistically. In vitro experiments show that the scaffold's oriented structure combined with electrical stimulation results in enhanced myotube formation, with a length of up to 863 µm and an orientation rate of 81%. Furthermore, the electrically stimulated scaffold displays a promoted muscle reconstruction ability when transplanted into rats with muscle defects, achieving a muscle mass and strength restoration ratio of 95% and 99%, respectively, compared to normal levels. These findings suggest that the scaffold has great potential in muscle repair applications.


Assuntos
Hidrogéis , Nanofios , Ratos , Animais , Hidrogéis/química , Anisotropia , Biomimética , Prata , Músculo Esquelético , Engenharia Tecidual/métodos , Estimulação Elétrica , Alicerces Teciduais/química , Gelatina/química
17.
Adv Mater ; 36(11): e2306553, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37845785

RESUMO

For electrolytes with conventional lithium salt concentration, it is not easy to generate sufficient anion-derived beneficial inorganic components to stabilize the electrolyte-lithium metal anode interface due to the repulsion of the free-state anions by the anode. In this study, the above issues are solved through the strong interaction between electronegative materials and lithium ions (Li+ ). A locally high Li+ concentration strategy is proposed by preparing micro-arrays of electronegative nano-hydroxyapatite (nHA) on the Cu foil. It is found that the oxygen atoms in the phosphate group (-PO4 ) of the nHA can strongly adsorb Li+ to form a locally Li+ -rich region, which increases the probability of anions interacting with Li+ . The formation of more Li+ -coordinated anions at the electrolyte-anode interface can reduce the Li+ de-solvation energy barrier, and enable the anions to completely decompose into lithium fluoride (LiF) and lithium nitride (Li3 N) on the Li metal anode. The interfacial transfer dynamics is accelerated and the Li dendrites are effectively suppressed. Under high current density, the anode exhibits a long lifespan with high Coulombic efficiency and small polarization voltage. The nHA micro-arrays achieve the targeted solvation structure at the electrolyte-anode interface while ensuring conventional lithium salt concentration in the bulk electrolyte.

18.
Langmuir ; 29(46): 14321-7, 2013 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-24144273

RESUMO

We demonstrate the preparation of peptide gel microparticles that are emulsified and stabilized by SiO2 nanoparticles. The gels are composed of aromatic peptide amphiphiles 9-fluorenylmethoxycarbonyldiphenylalanine (Fmoc-FF) coassembled with Fmoc-amino acids with different functional groups (S: serine; D: aspartic acid; K: lysine; and Y: tyrosine). The gel phase provides a highly hydrated matrix, and peptide self-assembly endows the matrix with tunable chemical environments which may be exploited to support and stabilize proteins. The use of Pickering emulsion to stabilize these gel particles is advantageous through avoidance of surfactants that may denature proteins. The performance of enzyme lipase B immobilized in pickering/gel microparticles with different chemical functionalities is investigated by studying transesterification in heptane. We show that the use of Pickering particles enhances the performance of the enzyme, which is further improved in gel-phase systems, with hydrophilic environment provided by Fmoc-FF/S giving rise to the best catalytic performance. The combination of a tunable chemical environment in gel phase and Pickering stabilization described here is expected to prove useful for areas where proteins are to be exploited in technological contexts such as biocatalysis and also in other areas where protein performance and activity are important, such as biosensors and bioinspired solar fuel devices.


Assuntos
Biocatálise , Peptídeos/química , Caprilatos/química , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Esterificação , Fluorenos/química , Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo , Géis , Heptanos/química , Lipase/química , Lipase/metabolismo , Modelos Moleculares , Nanopartículas/química , Octanóis/química , Conformação Proteica , Dióxido de Silício/química
19.
Macromol Biosci ; 23(12): e2300171, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37466295

RESUMO

The unique optical and electronic properties of living systems are impressive. Peptide-based supramolecular self-assembly systems attempt to mimic these properties by preparation optical/electronic function materials with specific structure through simple building blocks, rational molecular design, and specific kinetic stimulation. From the perspective of building blocks and assembly strategies, the unique optical and electronic properties of peptide-based nanostructures, including peptides self-assembly and peptides regulate the assembly of external function subunits, are systematically reviewed. Additionally, their applications in biomedicine, sensing, and energy storage are also highlighted. This bioinspired peptide-based function material is one of the hot candidates for the new generation of green intellect materials, with many advantages such as biocompatibility, environmental friendliness, and adjustable morphology.


Assuntos
Nanoestruturas , Nanoestruturas/química , Peptídeos/química , Cinética
20.
Cell Prolif ; 56(5): e13465, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37199010

RESUMO

Liver disease is one of the serious threats to human life and health. Three-dimensional (3D) liver models, which simulate the structure and function of natural liver tissue in vitro, have become a common demand in medical, scientific and pharmaceutical fields nowadays. However, the complex cellular composition and multi-scale spatial arrangement of liver tissue make it extremely challenging to construct liver models in vitro. According to HepaRG preference and printing strategy, the formulation of bioink system with opposite charge is optimized. The sodium alginate-based bioink 1 and dipeptide-based bioink 2 are used to ensure structural integrity and provide flexible designability, respectively. The HepaRG/HUVECs/LX-2-laden liver organoids with biomimetic lobule structure are fabricated by a multicellular 3D droplet-based bioprinting strategy, to mimic the cell heterogeneity, spatial structure and extracellular matrix (ECM) features. The liver organoids can maintain structural integrity and multicellular distribution within the printed lobule-like structure after 7 days of culture. Compared with the 2D monolayer culture, the constructed 3D organoids show high cell viability, ALB secretion and urea synthesis levels. This study provides a droplet-based and layer-by-layer 3D bioprinting strategy for in vitro construction of liver organoids with biomimetic lobule structure, giving meaningful insights in the fields of new drugs, disease modelling, and tissue regeneration.


Assuntos
Bioimpressão , Engenharia Tecidual , Humanos , Engenharia Tecidual/métodos , Bioimpressão/métodos , Biomimética , Impressão Tridimensional , Organoides , Fígado , Alicerces Teciduais/química
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