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1.
J Biol Chem ; 299(3): 102982, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36739947

RESUMO

Rheumatoid arthritis (RA) is one of the most common autoimmune diseases and affects almost 1% of the population. Differentiated embryo-chondrocyte expressed gene-1 (DEC1) has been associated with both osteogenesis and osteoclastogenesis. RA condition is marked by inflammatory hyperplasia, and DEC1 is known to support inflammatory reactions and implicated in antiapoptosis and cell invasion. Here, our goal was to test the hypothesis that DEC1 enhances RA development induced by collagen-induced arthritis (CIA), a well-recognized protocol for developing RA animal models. DEC1+/+ and DEC1-/- mice were subjected to CIA protocol, and the development of RA condition was monitored. We found that CIA robustly induced RA phenotypes (e.g., synovial hyperplasia) and greatly increased the expression of proinflammatory cytokines such as TNF-α. However, these changes were detected in DEC1+/+ but not DEC1-/- mice. Interestingly, these very cytokines strongly induced DEC1, and such a dual role of DEC1, as an inducer for and being induced by proinflammatory cytokines, constitutes a DEC1-amplifying circuit for inflammation. Knockdown of DEC1 in human MH7A cells strongly decreased cell migration and invasion as well as the expression of genes related to RA phenotypes. The combination of DEC1-directed migration and invasion in vitro with synovial hyperplasia in vivo mechanistically establishes cellular bases on how DEC1 is involved in the development of RA phenotypes. In addition to inflammatory signaling, DEC1 functionally interacted with PI3KCA(p110α)/Akt/GSK3ß, Wnt/ß-catenin, and NFATc1. Such engagement in multiple signaling pathways suggests that DEC1 plays coordinated and integral roles in developing RA, one of the most common autoimmune diseases.


Assuntos
Artrite Experimental , Artrite Reumatoide , Fatores de Transcrição Hélice-Alça-Hélice Básicos , Proteínas de Homeodomínio , Animais , Humanos , Camundongos , Artrite Experimental/induzido quimicamente , Artrite Experimental/genética , Artrite Reumatoide/genética , Colágeno , Citocinas/metabolismo , Fibroblastos/metabolismo , Hiperplasia/patologia , Inflamação/patologia , Membrana Sinovial/patologia , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Proteínas de Homeodomínio/metabolismo
2.
Small ; : e2402314, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38708815

RESUMO

Topology serves as a blueprint for the construction of reticular structures such as metal-organic frameworks, especially for those based on building blocks with highly symmetrical shapes. However, it remains a challenge to predict the topology of the frameworks from less symmetrical units, because their corresponding vertex figures are largely deformed from the perfect geometries with no "default" net embedding. Furthermore, vertices involving flexible units may have multiple shape choices, and the competition among their designated topologies makes the structure prediction in large uncertainty. Herein, the deformation index is proposed to characterize the symmetry loss of the vertex figure by comparing it with its ideal geometry. The mathematical index is employed to predict the shapes of two in situ formed Co-based metalloligands (pseudo-tetrahedron and pseudo-square), which further dictate the framework topology (flu and scu) when they are joined with the [Zr6O8]-based cuboid units. The two frameworks with very similar constituents provide an ideal platform to investigate how the pore shapes and interconnectivity influence the gas separation. The net with cylindrical channels outperforms the other with discreate cages in C3H8/C2H6/CH4 separation, benefiting from the facile accessibility of its interaction sites to the guests imposed by the specific framework topology.

3.
Phys Rev Lett ; 133(3): 036202, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39094151

RESUMO

Ferroelectric hafnia-based thin films have attracted significant interest due to their compatibility with complementary metal-oxide-semiconductor technology (CMOS). Achieving and stabilizing the metastable ferroelectric phase in these films is crucial for their application in ferroelectric devices. Recent research efforts have concentrated on the stabilization of the ferroelectric phase in hafnia-based films and delving into the mechanisms responsible for this stability. In this study, we experimentally demonstrate that stabilization of the ferroelectric phase in Hf_{0.5}Zr_{0.5}O_{2} (HZO) can be controlled by the interfacial charge transfer and the associated hole doping of HZO. Using the meticulously engineered charge transfer between an La_{1-x}Sr_{x}MnO_{3} buffer layer with variable Sr concentration x and an HZO film, we find the optimal x=0.33 that provides the required hole doping of HZO to most efficiently stabilize its ferroelectric phase. Our theoretical modeling reveals that the competition of the hole distribution between the threefold and fourfold coordinated oxygen sites in HZO controls the enhancement or reduction of the ferroelectric phase. Our findings offer a novel strategy to stabilize the ferroelectric phase of hafnia-based films and provide new insights into the development of ferroelectric devices compatible with CMOS.

4.
J Biomed Sci ; 31(1): 88, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39237902

RESUMO

BACKGROUND: Dysregulation of vascular homeostasis can induce cardiovascular diseases and increase global mortality rates. Although lineage tracing studies have confirmed the pivotal role of modulated vascular smooth muscle cells (VSMCs) in the progression of pathological vascular remodeling, the underlying mechanisms are still unclear. METHODS: The expression of Tudor-SN was determined in VSMCs of artery stenosis, PDGF-BB-treated VSMCs and atherosclerotic plaque. Loss- and gain-of-function approaches were used to explore the role of Tudor-SN in the modulation of VSMCs phenotype both in vivo and in vitro. RESULTS: In this study, we demonstrate that Tudor-SN expression is significantly elevated in injury-induced arteries, atherosclerotic plaques, and PDGF-BB-stimulated VSMCs. Tudor-SN deficiency attenuates, but overexpression aggravates the synthetic phenotypic switching of VSMCs and pathological vascular remodeling. Loss of Tudor-SN also reduces atherosclerotic plaque formation and increases plaque stability. Mechanistically, PTEN, the major regulator of the MAPK and PI3K-AKT signaling pathways, plays a vital role in Tudor-SN-mediated regulation on proliferation and migration of VSMCs. Tudor-SN facilitates the polyubiquitination and degradation of PTEN via NEDD4-1, thus exacerbating vascular remodeling under pathological conditions. BpV (HOpic), a specific inhibitor of PTEN, not only counteracts the protective effect of Tudor-SN deficiency on proliferation and migration of VSMCs, but also abrogates the negative effect of carotid artery injury-induced vascular remodeling in mice. CONCLUSIONS: Our findings reveal that Tudor-SN deficiency significantly ameliorated pathological vascular remodeling by reducing NEDD4-1-dependent PTEN polyubiquitination, suggesting that Tudor-SN may be a novel target for preventing vascular diseases.


Assuntos
Ubiquitina-Proteína Ligases Nedd4 , PTEN Fosfo-Hidrolase , Ubiquitinação , Remodelação Vascular , Ubiquitina-Proteína Ligases Nedd4/metabolismo , Ubiquitina-Proteína Ligases Nedd4/genética , Animais , Camundongos , PTEN Fosfo-Hidrolase/metabolismo , PTEN Fosfo-Hidrolase/genética , Músculo Liso Vascular/metabolismo , Masculino , Miócitos de Músculo Liso/metabolismo , Camundongos Endogâmicos C57BL
5.
J Chem Inf Model ; 64(15): 6132-6146, 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-39078379

RESUMO

Staphylococcus aureus (S. aureus) is a major global health concern, causing various infections and presenting challenges due to antibiotic resistance. In particular, methicillin-resistant S. aureus, vancomycin-intermediate S. aureus (VISA), and vancomycin-resistant S. aureus pose significant obstacles in treating S. aureus infections. Therefore, the critical need for novel drugs to counter these resistant forms is pressing. Two-component systems (TCSs), integral to bacterial regulation, offer promising targets for disruption. In this study, a comprehensive approach, involving pharmacophore-based inhibitor screening, along with biochemical and biophysical analyses were conducted to identify, characterize, and validate potential inhibitors targeting the response regulator VraRC of S. aureus. The constructed pharmacophore model, Phar-VRPR-N3, demonstrated effectiveness in identifying a potent inhibitor, TST1N-224 (IC50 = 60.2 ± 4.0 µM), against the formation of the VraRC-DNA complex. Notably, TST1N-224 exhibited strong binding to VraRC (KD = 23.4 ± 1.2 µM) using a fast-on-fast-off binding mechanism. Additionally, NMR-based molecular modeling revealed that TST1N-224 predominantly interacts with the α9- and α10-helixes of the DNA-binding domain of VraR, where the interactive and functionally essential residues (N165, K180, S184, and R195) act as hotspots for structure-based inhibitor optimization. Furthermore, TST1N-224 evidently enhanced the susceptibility of VISA to both vancomycin and methicillin. Importantly, TST1N-224 distinguished by 1,2,5,6-tetrathiocane with the 3 and 8 positions modified with ethanesulfonates holds significant potential as a lead compound for the development of new antimicrobial agents.


Assuntos
Antibacterianos , Proteínas de Bactérias , Antibacterianos/farmacologia , Antibacterianos/química , Proteínas de Bactérias/antagonistas & inibidores , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/química , Staphylococcus aureus/efeitos dos fármacos , Descoberta de Drogas , Testes de Sensibilidade Microbiana , Avaliação Pré-Clínica de Medicamentos , Simulação de Acoplamento Molecular , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Modelos Moleculares , Farmacóforo
6.
J Med Internet Res ; 26: e53450, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39052335

RESUMO

BACKGROUND: Resilience is a protective factor in healthy aging, helping to maintain and recover physical and mental functions. The Resilience in Illness Model has proven effective in fostering resilience and well-being. Physical activity is crucial for older adults' independence and well-being, even as aging causes a progressive decline. Additionally, older adults face challenges such as spousal loss and physical disability, making preventive intervention strategies necessary. OBJECTIVE: This study aims to develop and evaluate a web-based program to enhance resilience, physical activity, and well-being among community-dwelling older adults. Additionally, we aim to gather feedback on the program's strengths and limitations. METHODS: A 4-week resilience-enhancing program was created, incorporating role-play and talk-in-interaction and focusing on 3 key skills: coping, control belief, and manageability. The program included scenarios such as becoming widowed and suffering a stroke, designed to engage older adults. A pilot test preceded the intervention. As a result of the COVID-19 pandemic, the program shifted from in-person to web-based sessions. A single-blind, parallel-group, randomized controlled trial was conducted. Participants aged over 65 years were recruited offline and randomly assigned to either an intervention or control group. A certified resilience practitioner delivered the program. Outcomes in resilience, physical activity, and well-being were self-assessed at baseline (T0), 4 weeks (T1), and 12 weeks (T2) after the program. A mixed methods approach was used to evaluate feedback. RESULTS: A web-based participatory program enhancing 3 skills-coping, control belief, and manageability for resilience-was well developed. Among 96 participants, 63 were randomized into the intervention group (n=31) and the control group (n=32). The mean age in the intervention group was 69.27 (SD 3.08) years and 74.84 (SD 6.23) years in the control group. Significant between-group differences at baseline were found in age (t45.6=-4.53, P<.001) and physical activity at baseline (t61=2.92, P=.005). No statistically significant between-group differences over time were observed in resilience (SE 7.49, 95% CI -10.74 to 18.61, P=.60), physical activity (SE 15.18, 95% CI -24.74 to 34.74, P=.74), and well-being (SE 3.74, 95% CI -2.68 to 11.98, P=.21) after controlling for baseline differences. The dropout rate was lower in the intervention group (2/31, 6%) compared with the control group (5/32, 16%). Moreover, 77% (24/31) of participants in the intervention group completed the entire program. Program feedback from the participants indicated high satisfaction with the web-based format and mentorship support. CONCLUSIONS: This study demonstrated that a web-based resilience-enhancing program is appropriate, acceptable, feasible, and engaging for community-dwelling older adults. The program garnered enthusiasm for its potential to optimize resilience, physical activity, and well-being, with mentorship playing a crucial role in its success. Future studies should aim to refine program content, engagement, and delivery methods to effectively promote healthy aging in this population. TRIAL REGISTRATION: ClinicalTrials.gov NCT05808491; https://clinicaltrials.gov/ct2/show/NCT05808491.


Assuntos
Exercício Físico , Resiliência Psicológica , Humanos , Idoso , Feminino , Exercício Físico/psicologia , Masculino , COVID-19/prevenção & controle , COVID-19/psicologia , Intervenção Baseada em Internet , Adaptação Psicológica , Idoso de 80 Anos ou mais , Internet , Método Simples-Cego
7.
Angew Chem Int Ed Engl ; 63(25): e202404732, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38605561

RESUMO

The catalytic access of silicon-stereogenic organosilanes remains a big challenge, and largely depends on the desymmetrization of the symmetric precursors with two identical substitutes attached to silicon atom. Here we report the construction of silicon-stereogenic organosilanes via catalytic kinetic resolution of racemic monohydrosilanes with good to excellent selectivity factors. Both Si-stereogenic dihydrobenzosiloles and Si-stereogenic monohydrosilanes could be efficiently accessed in one single operation via Rh-catalyzed enantioselective intramolecular hydrosilylation, employing (R,R)-Et-DuPhos as the optimal ligand. This catalytic protocol features mild conditions, a low catalyst loading (0.1 mol % [Rh(cod)Cl]2), high stereoinduction (S factor up to 152), and excellent scalability. Moreover, further derivatizations led to the efficient synthesis of uncommon middle-size (7- and 8-membered) Si-stereogenic silacycles. Preliminary mechanistic study indicates this reaction might undergo a modified Chalk-Harrod mechanism.

8.
Angew Chem Int Ed Engl ; 63(20): e202402612, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38410071

RESUMO

The construction of silicon-stereogenic silanols via Pd-catalyzed intermolecular C-H alkenylation with the assistance of a commercially available L-pyroglutamic acid has been realized for the first time. Employing oxime ether as the directing group, silicon-stereogenic silanol derivatives could be readily prepared with excellent enantioselectivities, featuring a broad substrate scope and good functional group tolerance. Moreover, parallel kinetic resolution with unsymmetric substrates further highlighted the generality of this protocol. Mechanistic studies indicate that L-pyroglutamic acid could stabilize the Pd catalyst and provide excellent chiral induction. Preliminary computational studies unveil the origin of the enantioselectivity in the C-H bond activation step.

9.
Angew Chem Int Ed Engl ; 63(1): e202313336, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-37983653

RESUMO

The precise control of the regioselectivity in the transition metal-catalyzed migratory hydrofunctionalization of alkenes remains a big challenge. With a transient ketimine directing group, the nickel-catalyzed migratory ß-selective hydroarylation and hydroalkenylation of alkenyl ketones has been realized with aryl boronic acids using alkyl halide as the mild hydride source for the first time. The key to this success is the use of a diphosphine ligand, which is capable of the generation of a Ni(II)-H species in the presence of alkyl bromide, and enabling the efficient migratory insertion of alkene into Ni(II)-H species and the sequent rapid chain walking process. The present approach diminishes organosilanes reductant, tolerates a wide array of complex functionalities with excellent regioselective control. Moreover, this catalytic system could also be applied to the migratory hydroarylation of alkenyl azahetereoarenes, thus providing a general approach for the preparation of 1,2-aryl heteroaryl motifs with wide potential applications in pharmaceutical discovery.

10.
J Am Chem Soc ; 145(48): 26169-26178, 2023 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-37988478

RESUMO

Imaging-guided chemodynamic therapy is widely considered a promising modality for personalized and precision cancer treatment. Combining both imaging and chemodynamic functions in one system conventionally relies on the hybrid materials approach. However, the heterogeneous, ill-defined, and dissociative/disintegrative nature of the composites tends to complicate their action proceedings in biological environments and thus makes the treatment imprecise and ineffective. Herein, a strategy to employ two kinds of inorganic units with different functions─reactive oxygen species generation and characteristic emission─has achieved two single-crystalline metal-organic frameworks (MOFs), demonstrating the competency of reticular chemistry in creating multifunctional materials with atomic precision. The multinary MOFs could not only catalyze the transformation from H2O2 to hydroxyl radicals by utilizing the redox-active Cu-based units but also emit characteristic tissue-penetrating near-infrared luminescence brought by the Yb4 clusters in the scaffolds. Dual functions of MOF nanoparticles are further evidenced by pronounced cell imaging signals, elevated intracellular reactive oxygen species levels, significant cell apoptosis, and reduced cell viabilities when they are taken up by the HeLa cells. In vivo NIR imaging is demonstrated after the MOF nanoparticles are further functionalized. The independent yet interconnected modules in the intact MOFs could operate concurrently at the same cellular site, achieving a high spatiotemporal consistency. Overall, our work suggests a new method to effectively accommodate both imaging and therapy functions in one well-defined material for precise treatment.


Assuntos
Estruturas Metalorgânicas , Nanopartículas , Neoplasias , Humanos , Estruturas Metalorgânicas/farmacologia , Estruturas Metalorgânicas/química , Células HeLa , Espécies Reativas de Oxigênio , Peróxido de Hidrogênio , Fototerapia , Nanopartículas/química , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Linhagem Celular Tumoral
11.
J Am Chem Soc ; 145(18): 10431-10440, 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37099266

RESUMO

Great success in synthetic chemistry is motivated by the development of novel and reactive linchpins for carbon-carbon and carbon-heteroatom bond formation reactions, which has dramatically altered chemists' approach to building molecules. Herein, we report the ready synthesis of aryl sulfonium salts, a versatile electrophilic linchpin, via a novel Cu-mediated thianthrenation and phenoxathiination of commercially available arylborons with thianthrene and phenoxathiine, providing a series of aryl sulfonium salts in high efficiency. More importantly, by leveraging the sequential Ir-catalyzed C-H borylation and Cu-mediated thianthrenation of arylborons, the formal thianthrenation of arenes is also achieved. The Ir-catalyzed C-H borylation with undirected arenes normally occurred at the less steric hindrance position, thus providing a complementary method for thianthrenation of arenes in comparison with electrophilic thianthrenation. This process is capable of late-stage functionalization of a series of pharmaceuticals, which might find wide synthetic applications in both industry and academic sectors.

12.
BMC Neurosci ; 24(1): 53, 2023 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-37845642

RESUMO

Increasingly, non-pharmacological interventions are being identified and applied to post-stroke dysphagia. Nevertheless, there is insufficient evidence to assess which type of interventions are more effective. In this study, the randomized controlled trials of non-pharmacological interventions on post-stroke dysphagia were retrieved from the relevant databases. Including 96 studies and 12 non-drug treatments. Then, and the network meta-analysis is carried out by statistical software. The results show: In the aspects of videofluoroscopic swallowing study (VFSS), Standardized Swallowing Assessment (SSA), swallowing-quality of life (SWAL-QOL), Water swallow test (WST); Acupuncture + electrotherapy + rehabilitation training, acupuncture + rehabilitation training + massage, electrotherapy + rehabilitation training, acupuncture + electrotherapy + rehabilitation training, electrotherapy, acupuncture + rehabilitation training + acupoints sticking application have significant effects in post-stroke dysphagia. Compared with other interventions, they have more advantages in improving the above indicators. A substantial number of high-quality randomized clinical trials are still necessary in the prospective to validate the therapeutic effectiveness of non-pharmacological interventions in post-stroke dysphagia and the results of this Bayesian network meta-analysis.


Assuntos
Terapia por Acupuntura , Transtornos de Deglutição , Acidente Vascular Cerebral , Humanos , Transtornos de Deglutição/etiologia , Transtornos de Deglutição/terapia , Qualidade de Vida , Estudos Prospectivos , Teorema de Bayes , Metanálise em Rede , Resultado do Tratamento , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/terapia , Terapia por Acupuntura/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto
13.
Plant Cell Environ ; 46(4): 1157-1175, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36071575

RESUMO

Auxin is well known to stimulate coleoptile elongation and rapid seedling growth in the air. However, its role in regulating rice germination and seedling establishment under submergence is largely unknown. Previous studies revealed that excessive levels of indole-3-acetic acid(IAA) frequently cause the inhibition of plant growth and development. In this study, the high-level accumulation of endogenous IAA is observed under dark submergence, stimulating rice coleoptile elongation but limiting the root and primary leaf growth during anaerobic germination (AG). We found that oxygen and light can reduce IAA levels, promote the seedling establishment and enhance rice AG tolerance. miRNA microarray profiling and RNA gel blot analysis results show that the expression of miR167 is negatively regulated by submergence; it subsequently modulates the accumulation of free IAA through the miR167-ARF-GH3 pathway. The OsGH3-8 encodes an IAA-amido synthetase that functions to prevent free IAA accumulation. Reduced miR167 levels or overexpressing OsGH3-8 increase auxin metabolism, reduce endogenous levels of free IAA and enhance rice AG tolerance. Our studies reveal that poor seed germination and seedling growth inhibition resulting from excessive IAA accumulation would cause intolerance to submergence in rice, suggesting that a certain threshold level of auxin is essential for rice AG tolerance.


Assuntos
Germinação , Oryza , Plântula/metabolismo , Oryza/genética , Anaerobiose , Proteínas de Plantas/metabolismo , Ácidos Indolacéticos/metabolismo , Regulação da Expressão Gênica de Plantas
14.
Exp Dermatol ; 32(9): 1344-1349, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37140178

RESUMO

There have been several case reports regarding newly developed vitiligo following the coronavirus disease 19 (COVID-19) vaccination. However, the relationship between COVID-19 vaccine and vitiligo progression remains unclear. To explore the relationship between COVID-19 vaccine and vitiligo progression and its potential influencing factors, A cross-sectional study was conducted on 90 patients with vitiligo who received inactivated COVID-19 vaccination. Detailed information covering demographic characteristics (age and sex), vitiligo clinical features (disease subtypes, duration, stage and comorbidities) and disease activity was collected through an electronic questionnaire. Ninety patients with vitiligo included 44.4% males, with an average age of 38.1 years (standard deviation, SD = 15.0). Patients were divided into progress group (29, 32.2%) and normal group (61, 67.8%) based on whether they experienced vitiligo progression after inactivated COVID-19 vaccination. 41.3% of patients in the progress group experienced vitiligo progression within 1 week after vaccination, and disease progression mainly occurred after the first dose inoculation (20, 69.0%). Logistic regression revealed that patients aged <45 years (odds ratio (OR) was 0.87, 95% confidence interval (CI): 0.34-2.22) and male patients (OR = 0.84, 95% CI: 0.34-2.05) had lower risk for vitiligo progression, while patients with segmental vitiligo (SV) subtype (OR = 1.68, 95% CI: 0.53-5.33), with <5 years disease duration (OR = 1.32, 95% CI: 0.51-3.47) had higher risk for vitiligo progression after COVID-19 vaccination, but without statistical significance. Over 30% patients experienced vitiligo progression after inactivated COVID-19 vaccination, and female patients, elder age, shorter disease duration and SV subtype are potential risk factors for vitiligo progression.


Assuntos
COVID-19 , Vitiligo , Adulto , Idoso , Feminino , Humanos , Masculino , COVID-19/complicações , COVID-19/epidemiologia , COVID-19/prevenção & controle , Vacinas contra COVID-19/efeitos adversos , Estudos Transversais , Demografia , Vacinação/efeitos adversos , Vitiligo/epidemiologia , Vitiligo/etiologia , Pessoa de Meia-Idade
15.
An Acad Bras Cienc ; 95(2): e20201723, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37018836

RESUMO

Rating of perceived exertion (RPE) can serve as a more convenient and economical alternative to heart rate (HR) for exercise intensity control. This study aims to explore the influence of factors, such as indicators of demographic, anthropometric, body composition, cardiovascular function and basic exercise ability on the relationship between HR and RPE, and to develop the model predicting RPE from HR. 48 healthy participants were recruited to perform an incrementally 6-stage pedaling test. HR and RPE were collected during each stage. The influencing factors were identified with the forward selection method to train Gaussian Process regression (GPR), support vector machine (SVM) and linear regression models. Metrics of R2, adjusted R2 and RMSE were calculated to evaluate the performance of the models. The GPR model outperformed the SVM and linear regression models, and achieved an R2 of 0.95, adjusted R2 of 0.89 and RMSE of 0.52. Indicators of age, resting heart rate (RHR), Central arterial pressure (CAP), body fat rate (BFR) and body mass index (BMI) were identified as factors that best predicted the relationship between RPE and HR. It is possible to use GPR model to estimate RPE from HR accurately, after adjusting for age, RHR, CAP, BFR and BMI.


Assuntos
Exercício Físico , Esforço Físico , Humanos , Esforço Físico/fisiologia , Frequência Cardíaca/fisiologia , Exercício Físico/fisiologia , Modelos Lineares , Aprendizado de Máquina
16.
J Sports Sci ; 41(14): 1383-1392, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37885067

RESUMO

The importance of coach leadership to athlete development and performance has been identified in the literature. We respond to the call to investigate antecedents of coach transformational leadership and their indirect effects on athlete outcomes. We propose that coach extraversion as an antecedent of coach transformational leadership can indirectly impact follower cohesion and satisfaction. Building on this mediation model, we assert that educational environment (i.e., high school and university) may serve as a first-stage moderator between coach extraversion and transformational leadership. We used 48 coaches and their 570 athletes from competitive high school and university basketball teams to test this moderated mediation model. Our results indicate that coach extraversion indirectly impacts athlete cohesion and satisfaction via transformational leadership. Moreover, the indirect effects of coach extraversion on athlete outcomes via coach transformational leadership is conditionally significant only when coaches and athletes are in universities but not in high schools. Our findings highlight the importance of educational environment in determining the association between coach personality and leadership perception. Implications for research and practice are discussed.


Assuntos
Extroversão Psicológica , Liderança , Humanos , Motivação , Atletas , Personalidade
17.
Aesthet Surg J ; 43(5): 582-592, 2023 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-36446744

RESUMO

BACKGROUND: Preoperative planning for liposuction is vital to ensure safe practice and patient satisfaction. However, current standards of fat assessment before surgery are guided by subjective methods such as visual inspection, skin-pinch tests, and waist circumference measurements. OBJECTIVES: This study aimed to develop an inexpensive software-based tool that utilizes ultrasound (US) imaging and an online platform to accurately simulate regional subcutaneous adipose tissue (SAT) distribution and safe volume estimation for liposuction procedures. METHODS: The authors present a web-based platform with integrated 2-dimensional (2D) and 3-dimensional (3D) simulations of SAT to support liposuction planning and execution. SAT-Map was constructed using multiple sub-applications linked with the python framework programming language (Wilmington, DE). RESULTS: The SAT-Map interface provides an intuitive and fluid means of generating patient-specific models and volumetric data. To further accommodate this, an operational manual was prepared to achieve consistent visualization and examination of estimated SAT content. The system currently supports static 2D heatmap simulation and 3D interactive virtual modelling of the SAT distribution. Supplementary clinical studies are needed to evaluate SAT-Map's clinical performance and practicality. CONCLUSIONS: SAT-Map revolutionizes the concept of preoperative planning for liposuction by developing the first combined web-based software that objectively simulates fat distribution and measures safe liposuction volume. Our software approach presents a cost-efficient, accessible, and user-friendly system offering multiple advantages over current SAT assessment modalities. The immediacy of clinically accurate 3D virtual simulation provides objective support to surgeons towards improving patient conversation, outcomes, and satisfaction in liposuction procedures.


Assuntos
Lipectomia , Humanos , Lipectomia/métodos , Gordura Subcutânea/diagnóstico por imagem , Gordura Subcutânea/cirurgia , Distribuição da Gordura Corporal , Software , Internet
18.
Angew Chem Int Ed Engl ; 62(11): e202216878, 2023 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-36651564

RESUMO

Here, we report the first example of Ni-catalyzed asymmetric hydrosilylation of 1,1-disubstituted allenes with high level of regioselectivities and enantioselectivities. The key to achieve this stereoselective hydrosilylation reaction was the development of the SPSiOL-derived bisphosphite ligands (SPSiPO). This protocol features broad substrate scope, excellent functional group, and heterocycle tolerance, thus provides a versatile method for the construction of enantioenriched tertiary allylsilanes in a straightforward and atom-economic manner. DFT calculations were performed to reveal the reaction mechanism and the origins of the enantioselectivity.

19.
Angew Chem Int Ed Engl ; 62(5): e202216373, 2023 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-36465061

RESUMO

The transition metal-catalyzed cross-coupling reaction with Fischer metal carbene intermediates bearing an electron-rich alkoxyl or siloxyl group remains a big challenge due to the lack of readily available corresponding carbene precursors. Herein, we report the coupling of alkynes with the Fischer-type copper carbene species bearing a α-siloxyl group, which could be in situ generated from acylsilanes catalytically under photoirradiation and redox-neutral conditions. The side-arm modified bisoxazoline (SaBox) ligands prove to be crucial for this coupling reaction, which provides the corresponding alkynyl alcohol in high yields with remarkable heterocycle tolerance and broad substrate scope.

20.
Angew Chem Int Ed Engl ; 62(6): e202217864, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36479801

RESUMO

In contrast to the vast Al-oxo molecular cluster chemistry, Al-based building units for metal-organic framework (MOF) construction are limited in structural diversity and complexity. Synthesis of single crystalline MOFs based on this "hard" metal is further complicated by the poor reversibility of the Al-organic coordination linkages. Here, a strategy to employ two kinds of linkages with distinct strength-strong Al-carboxylate linkage and weak Cu-pyrazol N linkage-gives FDM-91 (FDM=Fudan Materials) with gigantic Al24 -based units. After replacing the weak moieties with organic linkers post-synthetically, two new stable MOFs with exceptional water harvesting capacity (up to 0.53 g g-1 ) and outstanding cycling performance are developed. Linkage-selective dissociation of FDM-91 further leads to the isolation of the Al24 molecular clusters. The versatile chemistry performed here to reinforce or deconstruct MOFs provides a new way to make important extended and discrete structures.

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