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1.
Carbohydr Polym ; 337: 122135, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38710549

RESUMO

The biggest obstacle to treating wound healing continues to be the production of simple, inexpensive wound dressings that satisfy the demands associated with full process of repair at the same time. Herein, a series of injectable composite hydrogels were successfully prepared by a one-pot method by utilizing the Schiff base reaction as well as hydrogen bonding forces between hydroxypropyl chitosan (HCS), ε-poly-l-lysine (EPL), and 2,3,4-trihydroxybenzaldehyde (TBA), and multiple cross-links formed by the reversible coordination between iron (III) and pyrogallol moieties. Notably, hydrogel exhibits excellent physicochemical properties, including injectability, self-healing, water retention, and adhesion, which enable to fill irregular wounds for a long period, providing a suitable moist environment for wound healing. Interestingly, the excellent hemostatic properties of the hydrogel can quickly stop bleeding and avoid the serious sequelae of massive blood loss in acute trauma. Moreover, the powerful antimicrobial and antioxidant properties also protect against bacterial infections and reduce inflammation at the wound site, thus promoting healing at all stages of the wound. The study of biohydrogel with multifunctional integration of wound treatment and smart medical treatment is clarified by this line of research.


Assuntos
Quitosana , Hemostáticos , Hidrogéis , Polilisina , Cicatrização , Cicatrização/efeitos dos fármacos , Hidrogéis/química , Hidrogéis/farmacologia , Quitosana/química , Quitosana/farmacologia , Quitosana/análogos & derivados , Polilisina/química , Polilisina/farmacologia , Animais , Hemostáticos/química , Hemostáticos/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Camundongos , Staphylococcus aureus/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Humanos , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Bases de Schiff/química , Bases de Schiff/farmacologia , Ratos
2.
Macromol Rapid Commun ; 44(24): e2300451, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37795776

RESUMO

Lithium-sulfur (Li-S) battery features a high theoretical energy density, but the shuttle of soluble polysulfides between the two electrodes often results in a rapid capacity decay. Herein, a straightforward electrostatic adsorption strategy based on a cross-linked polyimidazolium separator as a snaring shield of polysulfides is reported, which suppresses the undesirable migration of polysulfides to the anode. The porous ionic network (PIN)-modified carbon nanotubes (CNTs) are successfully prepared and coated onto a commercial porous polypropylene membrane in a vacuum-filtration step. The favorable affinity of the imidazolium ring toward polysulfide via the polar interaction and the electrostatic effect of ions mitigates the undesirable shuttle of polysulfides in the electrolyte, improving the Li─S battery in terms of rate performance and cycling life. Compared to the reference PIN-free CNT-coated separator, the PIN/CNT-coated one has an increased initial capacity of 1.3 folds (up to 1394.8 mAh g-1 for PIN/CNT/PP-3) at 0.1 C.


Assuntos
Lítio , Nanotubos de Carbono , Porosidade , Íons , Enxofre
3.
Exp Ther Med ; 26(2): 390, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37456167

RESUMO

Fibroblast growth factor 23 (FGF23) is an important phosphaturic hormone, yet few studies have focused on FGF23 in children with primary nephrotic syndrome (PNS) and children who progressed to end-stage renal disease (ESRD). This cross-sectional study investigated the significance of changes in FGF23 levels in childhood PNS and children who progressed to ESRD. Of the 41 children included in the study, 17 had PNS with proteinuria and normal renal function (PNS group), 4 had ESRD (ESRD group), and 20 were healthy (control group). Following corticosteroid treatment, patients with PNS and proteinuria entered the remission phase. Serum levels of FGF23, phosphate, parathyroid hormone (PTH), 25-hydroxyvitamin D (25-OH-D), and calcium were measured. It was found that FGF23 levels in the PNS and ESRD groups were higher than those in the control group, while serum 25-OH-D levels were lower. Serum PTH levels increased significantly in the ESRD group. In the control group, FGF23 levels were negatively correlated with serum PTH and positively correlated with serum 25-OH-D. FGF23 levels were positively correlated with serum calcium and corrected calcium levels in children with PNS during the remission phase. Increased FGF23 levels in children with PNS, particularly in children who progressed to ESRD. It was also confirmed that serum FGF23 levels begin to rise in children with PNS prior to Stage 1 chronic kidney disease. These findings indicated that increased FGF23 levels may be associated with the progression and severity of nephrosis in children, and that serum FGF23 levels were useful for early detection of abnormal mineral metabolism in children with PNS.

4.
Phys Rev Lett ; 131(2): 026701, 2023 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-37505968

RESUMO

In kagome metal CsV_{3}Sb_{5}, multiple intertwined orders are accompanied by both electronic and structural instabilities. These exotic orders have attracted much recent attention, but their origins remain elusive. The newly discovered CsTi_{3}Bi_{5} is a Ti-based kagome metal to parallel CsV_{3}Sb_{5}. Here, we report angle-resolved photoemission experiments and first-principles calculations on pristine and Cs-doped CsTi_{3}Bi_{5} samples. Our results reveal that the van Hove singularity (vHS) in CsTi_{3}Bi_{5} can be tuned in a large energy range without structural instability, different from that in CsV_{3}Sb_{5}. As such, CsTi_{3}Bi_{5} provides a complementary platform to disentangle and investigate the electronic instability with a tunable vHS in kagome metals.

5.
Nat Commun ; 14(1): 3819, 2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37369675

RESUMO

Van Hove singularity (VHS) has been considered as a driving source for unconventional superconductivity. A VHS in two-dimensional (2D) materials consists of a saddle point connecting electron-like and hole-like bands. In a rare case, when a VHS appears at Fermi level, both electron-like and hole-like conduction can coexist, giving rise to an enhanced density of states as well as an attractive component of Coulomb interaction for unconventional electronic pairing. However, this van Hove scenario is often destroyed by an incorrect chemical potential or competing instabilities. Here, by using angle-resolved photoemission measurements, we report the observation of a VHS perfectly aligned with the Fermi level in a kagome superconductor CsV3-xTaxSb5 (x ~ 0.4), in which a record-high superconducting transition temperature is achieved among all the current variants of AV3Sb5 (A = Cs, Rb, K) at ambient pressure. Doping dependent measurements reveal the important role of van Hove scenario in boosting superconductivity, and spectroscopic-imaging scanning tunneling microscopy measurements indicate a distinct superconducting state in this system.

6.
Sci Bull (Beijing) ; 67(5): 495-500, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36546170

RESUMO

Exotic quantum phenomena may appear in material systems with multiple orders or phases, where the mutual interactions can give rise to new physics beyond that of each component. Here, we report spectroscopic evidence for a unique combination of topology and correlation effects in the kagome superconductor CsV3Sb5. Topologically nontrivial surface states are observed near the Fermi energy (EF), indicating that the topological physics may be active upon entering the superconducting state. Flat bands are observed, suggesting that electron correlation effects are also at play in this system. Our results reveal the peculiar electronic structure of CsV3Sb5, which holds the potential for realizing Majorana zero modes and anomalous superconducting states in kagome lattices. They also establish CsV3Sb5 as a unique platform for exploring the interactions between the charge order, topology, correlation effects and superconductivity.

7.
Comput Intell Neurosci ; 2022: 3470764, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35498198

RESUMO

Breast cancer detection largely relies on imaging characteristics and the ability of clinicians to easily and quickly identify potential lesions. Magnetic resonance imaging (MRI) of breast tumors has recently shown great promise for enabling the automatic identification of breast tumors. Nevertheless, state-of-the-art MRI-based algorithms utilizing deep learning techniques are still limited in their ability to accurately separate tumor and healthy tissue. Therefore, in the current work, we propose an automatic and accurate two-stage U-Net-based segmentation framework for breast tumor detection using dynamic contrast-enhanced MRI (DCE-MRI). This framework was evaluated using T2-weighted MRI data from 160 breast tumor cases, and its performance was compared with that of the standard U-Net model. In the first stage of the proposed framework, a refined U-Net model was utilized to automatically delineate a breast region of interest (ROI) from the surrounding healthy tissue. Importantly, this automatic segmentation step reduced the impact of the background chest tissue on breast tumors' identification. For the second stage, we employed an improved U-Net model that combined a dense residual module based on dilated convolution with a recurrent attention module. This model was used to accurately and automatically segment the tumor tissue from healthy tissue in the breast ROI derived in the previous step. Overall, compared to the U-Net model, the proposed technique exhibited increases in the Dice similarity coefficient, Jaccard similarity, positive predictive value, sensitivity, and Hausdorff distance of 3%, 3%, 3%, 2%, and 16.2, respectively. The proposed model may in the future aid in the clinical diagnosis of breast cancer lesions and help guide individualized patient treatment.


Assuntos
Neoplasias da Mama , Algoritmos , Neoplasias da Mama/diagnóstico por imagem , Feminino , Humanos
8.
Artigo em Inglês | MEDLINE | ID: mdl-35564826

RESUMO

Thriving at work is beneficial to the physical and mental health of individuals, promotes the innovation and development of organizations, and is a shield against job burnout. However, the current research on the antecedents of thriving at work lacks the exploration of team characteristics. This study introduces team temporal leadership as a moderating variable and team time consensus as a mediating variable to explore the relationship between team cooperative goals and thriving at work. Based on the analysis of 326 data from 92 teams, the results showed that: (1) Team cooperative goals have a significant positive impact on team time consensus, and team time consensus has a significant positive impact on team thriving at work; (2) Team time consensus mediates the relationship between team cooperative goals and team thriving at work; and (3) Team temporal leadership not only moderated the relationship between team cooperative goals and team time consensus, but also moderated the indirect effect of team cooperative goals on team thriving at work through team time consensus. This study enriches the research on the triggering mechanism of thriving at work to some extent and provides enlightenment for organizations to stimulate the state of thriving at work.


Assuntos
Esgotamento Profissional , Comportamento Cooperativo , Consenso , Objetivos , Humanos , Liderança
9.
Polymers (Basel) ; 13(19)2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34641062

RESUMO

Nanocellulose, typically cellulose nanocrystals (CNCs), has excellent properties and is widely used. In particular, CNC has a small dimension, high chemical reactivity, and high sustainability, which makes it an excellent candidate as a starting material to be converted into nanocellulose derivatives. Chemical modification is essential for obtaining the desired products; the modifications create different functional attachment levels and generate novel microstructures. Recent advances on nanocellulose derivatives have not yet been reviewed and evaluated for the last five years. Nanocellulose derivative materials are being used in a wide variety of high-quality functional applications. To meet these requirements, it is essential for researchers to fully understand CNCs and derivative materials, precisely their characteristics, synthesis methods, and chemical modification approaches. This paper discusses CNC and its derivatives concerning the structural characteristics, performance, and synthesis methods, comparing the pros and cons of these chemical modification approaches reported in recent years. This review also discusses the critical physicochemical properties of CNC derivative products, including solubility, wetting performance, and associated impacts on properties. Lastly, this paper also comments on the bottlenecks of nanocellulose derivatives in various applications and briefly discusses their future research direction.

10.
Phys Rev Lett ; 127(26): 266401, 2021 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-35029485

RESUMO

We report angle resolved photoemission experiments on a newly discovered family of kagome metals RV_{6}Sn_{6} (R=Gd, Ho). Intrinsic bulk states and surface states of the vanadium kagome layer are differentiated from those of other atomic sublattices by the real-space resolution of the measurements with a small beam spot. Characteristic Dirac cone, saddle point, and flat bands of the kagome lattice are observed. Our results establish the two-dimensional (2D) kagome surface states as a new platform to investigate the intrinsic kagome physics.

11.
PLoS One ; 12(8): e0182259, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28813450

RESUMO

Several ecological hypotheses (e.g., specific plaque, non-specific plaque and keystone pathogen) regarding the etiology of periodontitis have been proposed since the 1990s, most of which have been centered on the concept of dysbiosis associated with periodontitis. Nevertheless, none of the existing hypotheses have presented mechanistic interpretations on how and why dysbiosis actually occurs. Hubbell's neutral theory of biodiversity offers a powerful null model to test hypothesis regarding the mechanism of community assembly and diversity maintenance from the metagenomic sequencing data, which can help to understand the forces that shape the community dynamics such as dysbiosis. Here we reanalyze the dataset from Abusleme et al.'s comparative study of the oral microbial communities from periodontitis patients and healthy individuals. Our study demonstrates that 14 out of 61 communities (23%) passed the neutrality test, a percentage significantly higher than the previous reported neutrality rate of 1% in human microbiome (Li & Ma 2016, Scientific Reports). This suggests that, while the niche selection may play a predominant role in the assembly and diversity maintenance in oral microbiome, the effect of neutral dynamics may not be ignored. However, no statistically significant differences in the neutrality passing rates were detected between the periodontitis and healthy treatments with Fisher's exact probability test and multiple testing corrections, suggesting that the mechanism of community assembly is robust against disturbances such as periodontitis. In addition, our study confirmed previous finding that periodontitis patients exhibited higher biodiversity. These findings suggest that while periodontitis may significantly change the community composition measured by diversity (i.e., the exhibition or 'phenotype' of community assembly), it does not seem to cause the 'mutation' of the 'genotype" (mechanism) of community assembly. We argue that the 'phenotypic' changes explain the observed link (not necessarily causal) between periodontitis and community dysbiosis, which is certainly worthy of further investigation.


Assuntos
Biodiversidade , Microbiota , Mucosa Bucal/microbiologia , Periodontite/microbiologia , Algoritmos , Estudos de Casos e Controles , Conjuntos de Dados como Assunto , Humanos , Metagenoma , Metagenômica/métodos , Modelos Teóricos
12.
Stud Health Technol Inform ; 225: 832-3, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27332365

RESUMO

Information technological advances to develop health care-related systems, Improve clinical efficiency through introducing information technology, Simplify processes to enhance the quality of nursing care. Study investigated the regional hospital nurses after initial information system the use of satisfaction surveys, Study for unit 50-bit nurse the use questionnaires collection, not satisfied is 30%, For analysis in found to be not satisfied. 1. Aged between 38-50 years old. 2. The operating practices are not familiar. 3. Typing is siow the fee time is more long. 4. The slow operation of the system. 5. Information ability is low. For the above reasons and after improvement and guidance dissatisfaction reduced to 5%, multi-enhancing information related to education and training in future, Increase nurses information literacy competency.


Assuntos
Atitude Frente aos Computadores , Alfabetização Digital/estatística & dados numéricos , Comportamento do Consumidor/estatística & dados numéricos , Sistemas de Informação Hospitalar/estatística & dados numéricos , Recursos Humanos de Enfermagem Hospitalar/estatística & dados numéricos , Revisão da Utilização de Recursos de Saúde , Atitude do Pessoal de Saúde , Informática em Enfermagem/estatística & dados numéricos , Registros de Enfermagem/estatística & dados numéricos , Projetos Piloto , Inquéritos e Questionários , Taiwan
13.
Exp Cell Res ; 304(1): 116-26, 2005 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-15707579

RESUMO

CD44, a widely expressed cell surface glycoprotein, plays a major role in cell-cell adhesion, cell-substrate interaction, lymphocyte homing, and tumor metastasis. For tumor metastasis to occur through the blood vessel and lymphatic vessel pathway, the tumor cells must first adhere to endothelial cells. Recent studies have shown that high expression of CD44 in certain types of tumors is associated with the hematogenic spread of cancer cells. However, the functional relevance of CD44 to tumor cell metastasis remains unknown. In this study, we investigated the mechanisms of CD44 cross-linking-induced adhesion and transendothelial migration of tumor cells using MDA-MB-435S breast cancer cell line. Breast cancer cells were found to express high levels of CD44. Using flow cytometric analysis and immunofluorescence staining, we demonstrated that cross-linking of CD44 resulted in a marked induction of the expression of lymphocyte function-associated antigen-1 (LFA-1) and very late antigen-4 (VLA-4) by exocytosis. These results were also observed with the Hs578T breast cancer cell line. Furthermore, LFA-1- and VLA-4-mediated adhesion and transendothelial cancer cell migration were also studied. Anti-LFA-1 mAb or anti-VLA-4 mAb alone had no effect on adhesion or transendothelial cancer cell migration, but were able to inhibit both of these functions when added together. This shows that CD44 cross-linking induces LFA-1 and VLA-4 expression in MDA-MB-435S cells and increases integrin-mediated adhesion to endothelial cells, resulting in the transendothelial migration of breast cancer cells. These observations provide direct evidence of a new function for CD44 that is involved in the induction of LFA-1 and VLA-4 expression by exocytosis in MDA-MB-435S cells. Because these induced integrins promote tumor cell migration into the target tissue, it may be possible to suppress this by pharmacological means, and thus potentially cause a reduction in invasive capability and metastasis.


Assuntos
Neoplasias da Mama/metabolismo , Neoplasias da Mama/fisiopatologia , Adesão Celular , Receptores de Hialuronatos/fisiologia , Integrina alfa4beta1/metabolismo , Integrinas/metabolismo , Antígeno-1 Associado à Função Linfocitária/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Movimento Celular , Células Endoteliais/metabolismo , Exocitose , Feminino , Humanos , Regulação para Cima
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