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1.
J Nanobiotechnology ; 22(1): 312, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38840221

RESUMO

Zinc oxide nanoparticles (ZNPs) are widely used in sunscreens and nanomedicines, and it was recently confirmed that ZNPs can penetrate stratum corneum into deep epidermis. Therefore, it is necessary to determine the impact of ZNPs on epidermis. In this study, ZNPs were applied to mouse skin at a relatively low concentration for one week. As a result, desmosomes in epidermal tissues were depolymerized, epidermal mechanical strain resistance was reduced, and the levels of desmosomal cadherins were decreased in cell membrane lysates and increased in cytoplasmic lysates. This finding suggested that ZNPs promote desmosomal cadherin endocytosis, which causes desmosome depolymerization. In further studies, ZNPs were proved to decrease mammalian target of rapamycin complex 1 (mTORC1) activity, activate transcription factor EB (TFEB), upregulate biogenesis of lysosome-related organelle complex 1 subunit 3 (BLOC1S3) and consequently promote desmosomal cadherin endocytosis. In addition, the key role of mTORC1 in ZNP-induced decrease in mechanical strain resistance was determined both in vitro and in vivo. It can be concluded that ZNPs reduce epidermal mechanical strain resistance by promoting desmosomal cadherin endocytosis via the mTORC1-TFEB-BLOC1S3 axis. This study helps elucidate the biological effects of ZNPs and suggests that ZNPs increase the risk of epidermal fragmentation.


Assuntos
Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos , Caderinas , Endocitose , Epiderme , Alvo Mecanístico do Complexo 1 de Rapamicina , Óxido de Zinco , Animais , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Endocitose/efeitos dos fármacos , Camundongos , Caderinas/metabolismo , Epiderme/metabolismo , Epiderme/efeitos dos fármacos , Óxido de Zinco/farmacologia , Óxido de Zinco/química , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Desmossomos/metabolismo , Nanopartículas/química , Estresse Mecânico
2.
Angew Chem Int Ed Engl ; 62(30): e202303048, 2023 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-37249478

RESUMO

Single atom alloy (SAA) catalysts have been recently explored for promotion of various heterogeneous catalysis, but it remains unexplored for selective electrocatalytic reduction of carbon dioxide (CO2 ) into multi-carbon (C2+ ) products involving C-C coupling. Herein we report a single-atomic Bi decorated Cu alloy (denoted as BiCu-SAA) electrocatalyst that could effectively modulate selectivity of CO2 reduction into C2+ products instead of previous C1 ones. The BiCu-SAA catalyst exhibits remarkably superior selectivity of C2+ products with optimal Faradaic efficiency (FE) of 73.4 % compared to the pure copper nanoparticle or Bi nanoparticles-decorated Cu nanocomposites, and its structure and performance can be well maintained at current density of 400 mA cm-2 under the flow cell system. Based on our in situ characterizations and density functional theory calculations, the BiCu-SAA is found to favor the activation of CO2 and subsequent C-C coupling during the electrocatalytic reaction, as should be responsible for its extraordinary C2+ selectivity.

3.
J Am Chem Soc ; 144(39): 18144-18152, 2022 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-36135972

RESUMO

Fe-N-C electrocatalysts have emerged as promising substitutes for Pt-based catalysts for the oxygen reduction reaction (ORR). However, their real catalytic active site is still under debate. The underlying roles of different types of coordinating N including pyridinic and pyrrolic N in catalytic performance require thorough clarification. In addition, how to understand the pH-dependent activity of Fe-N-C catalysts is another urgent issue. Herein, we comprehensively studied 13 different N-coordinated FeNxC configurations and their corresponding ORR activity through simulations which mimic the realistic electrocatalytic environment on the basis of constant-potential implicit solvent models. We demonstrate that coordinating pyrrolic N contributes to a higher activity than pyridinic N, and pyrrolic FeN4C exhibits the highest activity in acidic media. Meanwhile, the in situ active site transformation to *O-FeN4C and *OH-FeN4C clarifies the origin of the higher activity of Fe-N-C in alkaline media. These findings can provide indispensable guidelines for rational design of better durable Fe-N-C catalysts.

4.
Implant Dent ; 28(6): 578-589, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31205270

RESUMO

BACKGROUND: During implantation planning, dentists should be able to make an informed decision regarding whether to use an implant template to assist the surgery. PURPOSE: The aim of this meta-analysis was to assess the results of implantation with or without an implant template based on the accuracy, survival rate, and other considerations. MATERIALS AND METHODS: In January 2018, a systematic review was undertaken for randomized controlled trials and retrospective and prospective cohort studies with relevance to implant accuracy and the survival rate between the implant template and free-hand method. The odds ratios (ORs) of the survival rate and the mean difference of accuracy deviation from the selected papers were estimated by meta-analysis. RESULTS: Of the 362 screened articles, 6 studies were included in the meta-analysis. Comparison of the survival rate of implant surgery with or without an implant template revealed no significant result (OR = 1.71, 95% confidence interval [CI] 0.65-4.51). Significant differences in accuracy were observed in angular (mean difference = -5.45 degrees, 95% CI -0.66 to -4.24 degrees) and apical deviation (mean difference = -0.83 mm, 95% CI -1.12 to -0.54). CONCLUSIONS: With the technology of computer-aided surgical template, implant placement can be more accurate than free-hand operation. No significant difference is observed in the survival rate between template and free-hand.


Assuntos
Implantes Dentários , Cirurgia Assistida por Computador , Desenho Assistido por Computador , Implantação Dentária Endóssea , Planejamento de Assistência ao Paciente , Estudos Prospectivos , Estudos Retrospectivos
5.
J Oral Rehabil ; 46(12): 1192-1203, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31295755

RESUMO

The aim of this systematic review was to compare the survival rate, marginal bone loss changes and complications between short implants (5-8 mm) and long implants (≥10 mm) with a bone-augmented procedure in the posterior jaw. An electronic search of the MEDLINE (PubMed), Embase and Cochrane Library databases through September 2018 was done to identify randomised controlled trials (RCT) assessing short implants and long implants with at least a 1-year follow-up period after loading. A quantitative meta-analysis was conducted on the survival rate, marginal bone loss changes and complications. Ten RCTs met the inclusion criteria. There were no significant differences in the survival rate (RR: 1.01; 95% CI: [0.99, 1.03]; P = .32) and complications (RR: 0.48; 95% CI: [0.20, 1.17]; P = .11) between the two groups. Compared with the long implant group, the short implant group had a lower marginal bone loss change, and the effect measure was significant (mean difference: -0.13; 95% CI: [-0.20, -0.06]; P < .05). This systematic review showed no difference between the survival rates and complications of short implants (5-8 mm) and long implants (≥10 mm). The marginal bone loss changes in short implants are lower than those in long implants.


Assuntos
Aumento do Rebordo Alveolar , Implantes Dentários , Implantação Dentária Endóssea , Planejamento de Prótese Dentária , Prótese Dentária Fixada por Implante , Falha de Restauração Dentária , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
6.
Eur J Pharmacol ; 983: 176961, 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39209099

RESUMO

Cardiovascular diseases (CVD) are the leading cause of death worldwide, and advanced age is a main contributor to the prevalence of CVD. Cellular senescence is an irreversible state of cell cycle arrest that occurs in old age or after cells encounter various stresses. Senescent cells not only result in the reduction of cellular function, but also produce senescence-associated secretory phenotype (SASP) to affect surrounding cells and tissue microenvironment. There is increasing evidence that the gradual accumulation of senescent cardiomyocytes is causally involved in the decline of cardiovascular system function. To highlight the role of senescent cardiomyocytes in the pathophysiology of age-related CVD, we first introduced that senescent cardiomyoyctes can be identified by structural changes and several senescence-associated biomarkers. We subsequently provided a comprehensive summary of existing knowledge, outlining the compelling evidence on the relationship between senescent cardiomyocytes and age-related CVD phenotypes. In addition, we discussed that the significant therapeutic potential represented by the prevention of accelerated senescent cardiomyocytes, and the current status of some existing geroprotectors in the prevention and treatment of age-related CVD. Together, the review summarized the role of cardiomyocyte senescence in CVD, and explored the molecular knowledge of senescent cardiomyocytes and their potential clinical significance in developing senescent-based therapies, thereby providing important insights into their biology and potential therapeutic exploration.

7.
Psych J ; 12(4): 547-560, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37220758

RESUMO

Negativity bias refers to the phenomenon whereby people put more weight on negative information. Although evolutionarily favorable for survival, negative bias in impression processing is detrimental to relationships and cooperation. To explore whether the motivation to maintain relationships, indicated by self-construal, mitigates negativity bias, two studies were conducted. In study 1, participants interacted with three agents (worsened, improved, baseline) in a modified social learning task and evaluated the moral level of these agents. Results showed that positivity bias appeared among interdependent individuals, with larger updating for the improved agent than for the worsened agent. Moreover, interdependent individuals exhibited less immediate decreases toward the worsened agent and steeper increases toward the improved agent than did independent individuals. To validate the results of study 1, we used a narrative description paradigm in study 2. Participants read the behavior descriptions of agents and rated them on morality. The negativity bias was significantly mitigated among individuals with high interdependence, though it did not reverse. These results indicate that interdependent individuals focus more on positive information when others change, yielding a more positive pattern in impression updating. This flexible interpersonal coping strategy can bring advantages to social interaction and cooperation.


Assuntos
Motivação , Autoimagem , Humanos , Adaptação Psicológica
8.
Neuropsychologia ; 172: 108274, 2022 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-35623449

RESUMO

The ability to control unwanted memories is essential for emotional regulation and maintaining mental health. Previous evidence indicates that suppressing retrieval, which recruits executive control mechanisms to prevent unwanted memories entering consciousness, can cause forgetting, termed suppression-induced forgetting (SIF). Since these executive mechanisms involve multiple mental operations, we hypothesize that the efficacy of SIF may be limited by individuals' capacity limitation of cognitive control. Here, we tested this hypothesis. Participants were assigned to two groups based on the median of their cognitive control capacity (CCC, estimated by the backward masking majority function task) and performed the think/no-think task with electrophysiological signals recorded. The results showed that the SIF effect was observed only in the high CCC group but not in the low CCC group. In accordance, repeated suppression attempts also resulted in a steeper reduction in intrusive thoughts in the high CCC group. Furthermore, ERP analysis revealed a decrease in recollection-related late parietal positivity (LPP) under the no-think condition in the high CCC group. A mediation analysis revealed that the reduced intrusive memories mediated the effect of CCC on SIF. These findings suggest that suppressing retrieval could reduce traces of the unwanted memories, making them less intrusive and harder to recall. More importantly, successful SIF is constrained by the capacity of cognitive control which may be used to ensure the coordination of multiple cognitive processes during suppression.


Assuntos
Cognição , Rememoração Mental , Cognição/fisiologia , Função Executiva , Humanos , Rememoração Mental/fisiologia
9.
Exp Ther Med ; 8(4): 1047-1054, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25187795

RESUMO

The aim of the present study was to compare the root canal preparation ability of rotary nickel-titanium (NiTi) Hero 642 and K3 files in curved mandibular or maxillary molars. A total of 40 extracted mandibular molars with two separate mesial canals, an apical width of approximately size ≤15 and a root canal curvature of 15-30° were randomly divided into two groups and instrumented using Hero 642 (n=20) or K3 files (n=20). Canal straightening, working length, transportation, cross-sectional area, minimum dentin thickness and the canal angle curvature degree were examined, and a systematic review of the literature was conducted. No statistically significant differences were observed between the two groups with regard to the mean degree of straightening, mean change in working length, mean transportation, amount of dentin removed or remaining minimum dentin thickness (P>0.05). The canal angle curvature decreased in the two groups postoperatively. The systematic review identified six studies, and overall the two files performed similarly in the majority of categories examined. Therefore, the rotary NiTi Hero 642 and K3 files demonstrated comparable shaping abilities and maintenance of working length.

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