Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 320
Filtrar
1.
Soft Robot ; 2024 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-39360431

RESUMO

The unique rigid-flex connection between the fin-rays and fin-surface in a bionic undulatory fin robot endows the fin-surface with both active flexibility and load-bearing capacity, enabling this robot to perform amphibious motions in underwater, terrestrial, and even marshy environments. However, investigations into dynamic modeling problems for the undulatory fin robot, considering the impact of nonlinear deformation and frictional contact on ground locomotion performance, are scarce. Given this, based on the absolute nodal coordinate formulation (ANCF), this paper presents an efficient and accurate nonlinear dynamic model for this robot to elucidate the fin's flexible deformation and motion law. This model considers material, geometric, and boundary nonlinearities, utilizing ANCF thin plate elements and reference nodes to individually describe the fin-surface and fin-rays of the undulatory fin. Then, by using the master-slave technique, a frictional contact formulation for the fin and the ground is proposed. Furthermore, we conduct in-depth research and analysis on the formation and undulatory motion of the undulatory fin, encompassing its static deformation, static contact deformation, and frictional contact motion, and successfully obtain its responses under various conditions. Research indicates that during fin-surface motion, longitudinal sliding or a tendency for sliding at the contact points results in the undulatory fin moving in a crawling gait. The proposed theoretical model correctly captures the fin's complex nonlinear deformations and frictional characteristics and reveals its ground locomotion mechanism, whose effectiveness and superiority are validated through numerical examples and experiments.

2.
Front Nutr ; 11: 1430722, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39257604

RESUMO

Background: Nutritional support has been identified as a potential intervention for cognitive frailty; however, the association between 25-hydroxyvitamin D [25-(OH)D], vitamin B12, and cognitive frailty remains ambiguous. Methods: This study utilized data from two cycles (2011-2012, 2013-2014) of the National Health and Nutrition Examination Survey (NHANES) to investigate this relationship. The researchers constructed a 41-item frailty index encompassing diverse aspects of physical functioning, psychological evaluation, and medical conditions, and evaluated each participant individually. The study utilized Spearman's rank correlation coefficient and univariate ordered logistic regression to assess the relationships between variables and cognitive frailty. Recursive feature elimination and cross-validation methods were employed to identify the most influential variables for building and optimizing multivariate ordered logistic regression models. Subgroup analyses and interaction tests were further conducted to validate the identified correlations. Results: The findings of this study confirm a negative linear correlation between 25-(OH)D levels and cognitive frailty in older adults. Specifically, a one-unit increase in 25-(OH)D levels was associated with a 12% reduction in the risk of cognitive frailty. The result was further supported by subgroup analyses and interaction tests. Conclusion: The existence of a negatively correlated linear association between 25-(OH)D levels and cognitive frailty in older adults is plausible, but further rigorously designed longitudinal studies are necessary to validate this relationship.

3.
Asian J Endosc Surg ; 17(4): e13378, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39245633

RESUMO

Robotic surgery has been widely used in surgical gastric cancer treatments, including proximal gastrectomy. Single-port robotic system is gaining more popularity in robotic surgery, but there has been no report on its application in robotic proximal gastrectomy with right-sided overlap and single-flap valvuloplasty (RPG-ROSF). Here, we report an RPG-ROSF using a novel single-port robotic system in a 51-year-old male patient with an early-stage gastroesophageal cancer detected by gastroscopy. It took 90 min for robotic setup, 143 min for dissection, and 161 min for digestive tract reconstruction. There was no complication during and after the surgery. The patient was discharged in 8 days postsurgery. The pathological staging of the adenocarcinoma was pT1aN0M0. This preliminary study demonstrated the feasibility and safety of a novel single-port robot in RPG-ROSF.


Assuntos
Adenocarcinoma , Gastrectomia , Procedimentos Cirúrgicos Robóticos , Neoplasias Gástricas , Humanos , Masculino , Gastrectomia/métodos , Neoplasias Gástricas/cirurgia , Neoplasias Gástricas/patologia , Pessoa de Meia-Idade , Adenocarcinoma/cirurgia , Adenocarcinoma/patologia , Neoplasias Esofágicas/cirurgia , Neoplasias Esofágicas/patologia , Retalhos Cirúrgicos
4.
BMC Cancer ; 24(1): 1096, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39227821

RESUMO

BACKGROUND: The effectiveness of palliative gastrectomy for advanced GC remains a topic of debate. This study sought to establish whether palliative gastrectomy has an impact on prolonging survival. METHODS: We carried out systematic searches in PubMed, Cochrane Library, Web of Science, and the EMBASE databases from database inception to July 2023 to gather studies that examined the connection between palliative gastrectomy and the prognosis of advanced GC. The study employed overall survival as the primary outcome, with the hazard ratio serving as the selected parameter to gauge the association. Subgroup analyses were performed to delve into potential differences within the included studies, categorizing them by study region and sample size in order to examine possible sources of heterogeneity. The stability of individual studies was assessed through sensitivity analysis. The analysis included 20 articles, encompassing a total of 23,061 patients. RESULTS: According to the meta-analysis results, patients who underwent palliative gastrectomy exhibited a noteworthy enhancement in overall survival (HR: 1.49; 95% CI: 1.12-1.99; P = 0.006) in comparison to those who did not receive this procedure. There was no association between the type of surgery and the length of hospital stay, as revealed by the analysis (HR = -0.02; 95% CI: -0.84-0.81; P = 0.970). CONCLUSIONS: Based on this meta-analysis, patients with advanced gastric cancer who underwent palliative gastrectomy may experience an extended survival duration without a significant prolongation of their hospitalization.


Assuntos
Gastrectomia , Cuidados Paliativos , Neoplasias Gástricas , Neoplasias Gástricas/cirurgia , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/patologia , Humanos , Gastrectomia/métodos , Prognóstico , Tempo de Internação/estatística & dados numéricos
5.
Angew Chem Int Ed Engl ; : e202413901, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39221519

RESUMO

The development of a mechanochemical Fe-catalyzed Wacker oxidation of olefins with a sustainable and benign procedure holds significant promise for industrial applications. However, navigating the intricate interactions inherent in ball-milling conditions to fine-tune reaction selectivity remains a formidable challenge. Herein, leveraging the dispersive and/or trapping properties of cyclodextrins, an innovative mechanochemical approach is developed through the integration of cyclodextrins into a Fe-catalyzed system, enabling a streamlined Wacker oxidation process from simple and/or commercially available alkenes. Our efforts have yielded optimized mechanochemical conditions demonstrating exceptional reactivity and selectivity in generating a diverse array of ketone products, markedly enhancing catalytic efficiency compared to conventional batch methods. Mechanistic investigations have revealed a predominantly Markovnikov-selective catalytic cycle, effectively minimizing undesired alcohol formation, hydrogenation, and the other competing pathways, boosting both reaction yield and selectivity.

6.
Arthroscopy ; 2024 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-39128679

RESUMO

PURPOSE: To enhance the understanding of histologic healing after repairing medial meniscal posterior root tears (MMPRTs) at an early stage, utilizing a goat model. METHODS: Eighteen adult goats, totaling 36 knee joints, were allocated into 3 groups (n = 12): sham group (Sham), root tear group (RT), and root tear with transosseous suture group (RTS). At 12- and 24-week intervals postsurgery, all the knees were harvested for imaging, macroscopic, histologic, and biomechanical assessments. RESULTS: The intact root served as a meniscus-bone interface that connected the tibial and circular fibers of the meniscus with a bony insertion and a root-meniscus transition. A direct fibrous connection was displayed at the bony insertion proximal to the synovium in the RTS group, while the remaining regions of the root displayed indirect fibrous healing. The healing in the RT group was disjointed and reminiscent of scar tissue. The RTS group exhibited a more pronounced coronal extrusion compared to the Sham group (0.42 ± 0.09 vs 0.19 ± 0.02, P = .0012) but was improved relative to that of the RT group (0.49 ± 0.02, P = .0028). The failure load and stiffness of the RTS group were notably higher than those of the RT group, with a strength of 42.67% and a stiffness of 83.75% of the intact root. All the samples ruptured at the root-meniscus transitions. CONCLUSIONS: The incomplete healing may be attributed to the histologic factors underlying the low healing rate and persistent medial meniscal extrusion. Notably, the region attached to the posterior cruciate ligament exhibited superior healing compared to other regions of the bony insertion in the repaired group. Conversely, the root-meniscus transition displayed discontinuity, representing a mechanical weakness in the healing process. CLINICAL RELEVANCE: Modifications of bone tunnel positioning and suture placement could be undertaken in subsequent studies to enhance the healing of the root-meniscus transition.

7.
Mol Carcinog ; 2024 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-39185663

RESUMO

A multifunctional polydopamine/mesoporous silica nanoparticles loaded cryptotanshinone (PDA/MSN@CTS) was synthesized and subjected to investigating its physicochemical properties and anti-gastric cancer (GC) effects. Utilizing network pharmacology and molecular docking techniques, CTS was identified as our final research target. The structural morphology and physicochemical properties of PDA/MSN@CTS were examined. Near-infrared (NIR) laser was employed to evaluate the photothermal properties of the PDA/MSN@CTS, along with pH-responsive and NIR-triggered release assessments. In vitro experiments evaluated the impact of PDA/MSN@CTS on the malignant behavior of AGS gastric cells. A subcutaneous tumor model was further established to evaluate the in vivo safety of PDA/MSN@CTS. Furthermore, the in vivo photothermal efficacy of PDA/MSN@CTS, in addition to its combined effect with photothermal therapy (PTT), was investigated. Uniform and stable PDA/MSN@CTS had been successfully synthesized and demonstrated efficient release under tumor environment and NIR irradiation. Upon increasing NIR laser conditions, in vivo cytotoxicity, apoptosis rate, reactive oxygen species scavenging ability, and suppression of migration and invasion of AGS cells by PDA/MSN@CTS were significantly enhanced. In vivo assessments revealed excellent blood compatibility and biosafety of PDA/MSN@CTS, alongside robust tumor tissue targeting. Combining nanoparticles with PTT facilitated the anti-GC effects of PDA/MSN@CTS. Compared to free drugs, PDA/MSN@CTS exhibits higher selectivity towards cancer cells, demonstrating effective anticancer activity and biocompatibility both in vitro and in vivo. Furthermore, our nanomaterial possesses excellent photothermal properties, and under NIR conditions, PDA/MSN@CTS exhibits synergistic therapeutic effects.

8.
Bioorg Chem ; 152: 107734, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39167871

RESUMO

Because of the high similarity in structure and sequence, it is challenging to distinguish the S1 pocket among serine proteases, primarily due to the only variability at residue 190 (A190 and S190). Peptide or protein-based inhibitors typically target the negatively charged S1 pocket using lysine or arginine as the P1 residue, yet neither discriminates between the two S1 pocket variants. This study introduces two arginine analogues, L-4-guanidinophenylalanine (12) and L-3-(N-amidino-4-piperidyl)alanine (16), as novel P1 residues in peptide inhibitors. 16 notably enhances affinities across all tested proteases, whereas 12 specifically improved affinities towards proteases possessing S190 in the S1 pocket. By crystallography and molecular dynamics simulations, we discovered a novel mechanism involving a water exchange channel at the bottom of the S1 pocket, modulated by the variation of residue 190. Additionally, the specificity of 12 towards the S190-presenting S1 pocket is dependent on this water channel. This study not only introduces novel P1 residues to engineer inhibitory potency and specificity of peptide inhibitors targeting serine proteases, but also unveils a water-mediated molecular mechanism of targeting serine proteases.


Assuntos
Arginina , Simulação de Dinâmica Molecular , Serina Proteases , Inibidores de Serina Proteinase , Água , Água/química , Serina Proteases/metabolismo , Serina Proteases/química , Inibidores de Serina Proteinase/farmacologia , Inibidores de Serina Proteinase/química , Inibidores de Serina Proteinase/síntese química , Arginina/química , Relação Estrutura-Atividade , Humanos , Estrutura Molecular , Relação Dose-Resposta a Droga , Cristalografia por Raios X
9.
J Hazard Mater ; 477: 135383, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-39094316

RESUMO

Multi-compartment dental clinics present significant airborne cross-infection risks. Upper-room ultraviolet germicidal irradiation (UR-UVGI) system have shown promise in preventing airborne pathogens, but its available application data are insufficient in multi-compartment dental clinics. Therefore, the UR-UVGI system's performance in a multi-compartment dental clinic was comprehensively evaluated in this study. The accuracy of the turbulence and drift flux models was verified by experimental data from ultrasonic scaling. The effects of the ventilation rate, irradiation zone volume, and irradiation flux on UR-UVGI performance were analyzed using computational fluid dynamics coupled with a UV inactivation model. Different patient numbers were considered. The results showed that UR-UVGI significantly reduced virus concentrations and outperformed increased ventilation rates alone. At a ventilation rate of six air changes per hour (ACH), UR-UVGI with an irradiation zone volume of 20% and irradiation flux of 5 µW/cm2 achieved a 70.44% average virus reduction in the whole room (WR), outperforming the impact of doubling the ventilation rate from 6 to 12 ACH without UR-UVGI. The highest disinfection efficiency of UR-UVGI decreased for WRs with more patients. The compartment treating patients exhibited significantly lower disinfection efficiency than others. Moreover, optimal UR-UVGI performance occurs at lower ventilation rates, achieving over 80% virus disinfection in WR. Additionally, exceeding an irradiation zone volume of 20% or an irradiation flux of 5 µW/cm2 notably reduces the improvement rates of UR-UVGI performance. These findings provide a scientific reference for strategically applying UR-UVGI in multi-compartment dental clinics.


Assuntos
Microbiologia do Ar , Clínicas Odontológicas , Desinfecção , Raios Ultravioleta , Desinfecção/métodos , Humanos , Ventilação
10.
Adv Sci (Weinh) ; 11(33): e2402412, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38958533

RESUMO

Meiosis is a specialized cell division process that generates gametes for sexual reproduction. However, the factors and underlying mechanisms involving meiotic progression remain largely unknown, especially in humans. Here, it is first showed that HSF5 is associated with human spermatogenesis. Patients with a pathogenic variant of HSF5 are completely infertile. Testicular histologic findings in the patients reveal rare postmeiotic germ cells resulting from meiotic prophase I arrest. Hsf5 knockout (KO) mice confirms that the loss of HSF5 causes defects in meiotic recombination, crossover formation, sex chromosome synapsis, and sex chromosome inactivation (MSCI), which may contribute to spermatocyte arrest at the late pachytene stage. Importantly, spermatogenic arrest can be rescued by compensatory HSF5 adeno-associated virus injection into KO mouse testes. Mechanistically, integrated analysis of RNA sequencing and chromatin immunoprecipitation sequencing data revealed that HSF5 predominantly binds to promoters of key genes involved in crossover formation (e.g., HFM1, MSH5 and MLH3), synapsis (e.g., SYCP1, SYCP2 and SYCE3), recombination (TEX15), and MSCI (MDC1) and further regulates their transcription during meiotic progression. Taken together, the study demonstrates that HSF5 modulates the transcriptome to ensure meiotic progression in humans and mice. These findings will aid in genetic diagnosis of and potential treatments for male infertility.


Assuntos
Infertilidade Masculina , Prófase Meiótica I , Camundongos Knockout , Espermatogênese , Masculino , Animais , Camundongos , Humanos , Espermatogênese/genética , Infertilidade Masculina/genética , Prófase Meiótica I/genética , Modelos Animais de Doenças , Meiose/genética , Fatores de Transcrição de Choque Térmico/genética , Fatores de Transcrição de Choque Térmico/metabolismo , Adulto , Azoospermia/congênito
11.
J Dig Dis ; 25(6): 361-367, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38988129

RESUMO

OBJECTIVES: The Japan NBI Expert Team (JNET) classification has good diagnostic potential for colorectal diseases. We aimed to explore the diagnostic value of the JNET classification type 2B (JNET2B) criteria for colorectal laterally spreading tumors (LSTs) based on magnifying endoscopy with blue laser imaging (ME-BLI) examination. METHODS: Between January 2017 and June 2023, 218 patients who were diagnosed as having JNET2B-type LSTs using ME-BLI were included retrospectively. Endoscopic images were reinterpreted to categorize the LSTs as JNET2B-low (n = 178) and JNET2B-high (n = 53) LSTs. The JNET2B-low and JNET2B-high LSTs were compared based on their histopathological and morphological classifications. RESULTS: Among the 178 JNET2B-low LSTs, 86 (48.3%) were histopathologically classified as low-grade intraepithelial neoplasia, 54 (30.3%) as high-grade intraepithelial neoplasia (HGIN), 37 (20.8%) as intramucosal carcinoma (IMC), and one (0.6%) as superficial invasive submucosal carcinoma (SMC1). Among the 53 JNET2B-high LSTs, five (9.4%) were classified as HGIN, 28 (52.9%) as IMC, 15 (28.3%) as SMC1, and 5 (9.4%) as deep invasive submucosal carcinoma. There were significant differences in this histopathological classification between the two groups (P < 0.001). However, there was no significant difference between JNET2B-low and JNET2B-high LSTs based on their morphological classification (granular vs nongranular) or size (<20 mm vs ≥20 mm). Besides, the κ value for JNET2B subtyping was 0.698 (95% confidence interval 0.592-0.804) between the two endoscopists who reassessed the endoscopic images. CONCLUSION: The JNET2B subtyping of LSTs has a diagnostic potential in the preoperative setting, and may be valuable for treatment decision-making.


Assuntos
Colonoscopia , Neoplasias Colorretais , Humanos , Neoplasias Colorretais/classificação , Neoplasias Colorretais/patologia , Neoplasias Colorretais/diagnóstico por imagem , Feminino , Masculino , Estudos Retrospectivos , Pessoa de Meia-Idade , Idoso , Japão , Colonoscopia/métodos , Imagem de Banda Estreita/métodos , Adulto , Idoso de 80 Anos ou mais , Carcinoma in Situ/diagnóstico por imagem , Carcinoma in Situ/patologia , Carcinoma in Situ/classificação
12.
Life (Basel) ; 14(7)2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39063634

RESUMO

The control region (CR) regulates the replication and transcription of the mitochondrial genome (mitogenome). Some avian mitogenomes possess two CRs, and the second control region (CR2) may enhance replication and transcription; however, the CR2 in lark mitogenome appears to be undergoing loss and is accompanied by tandem repeats. Here, we characterized six lark mitogenomes from Alaudala cheleensis, Eremophila alpestris, Alauda razae, and Calandrella cinerea and reconstructed the phylogeny of Passerida. Through further comparative analysis among larks, we traced the evolutionary process of CR2. The mitochondrial gene orders were conserved in all published lark mitogenomes, with Cytb-trnT-CR1-trnP-ND6-trnE-remnant CR2 with tandem repeat-trnF-rrnS. Phylogenetic analysis revealed Alaudidae and Panuridae are sister groups at the base of Sylvioidea, and sporadic losses of CR2 may occur in their common ancestor. CR sequence and phylogeny analysis indicated CR2 tandem repeats were generated within CR2, originating in the ancestor of all larks, rather than inherited from CR1. The secondary structure comparison of tandem repeat units within and between species suggested slipped-strand mispairing and DNA turnover as suitable models for explaining the origin and evolution of these repeats. This study reveals the evolutionary process of the CR2 containing tandem repeat in Alaudidae, providing reference for understanding the evolutionary characteristics and dynamics of tandem repeats.

13.
Elife ; 122024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39028117

RESUMO

IQ motif-containing proteins can be recognized by calmodulin (CaM) and are essential for many biological processes. However, the role of IQ motif-containing proteins in spermatogenesis is largely unknown. In this study, we identified a loss-of-function mutation in the novel gene IQ motif-containing H (IQCH) in a Chinese family with male infertility characterized by a cracked flagellar axoneme and abnormal mitochondrial structure. To verify the function of IQCH, Iqch knockout (KO) mice were generated via CRISPR-Cas9 technology. As expected, the Iqch KO male mice exhibited impaired fertility, which was related to deficient acrosome activity and abnormal structures of the axoneme and mitochondria, mirroring the patient phenotypes. Mechanistically, IQCH can bind to CaM and subsequently regulate the expression of RNA-binding proteins (especially HNRPAB), which are indispensable for spermatogenesis. Overall, this study revealed the function of IQCH, expanded the role of IQ motif-containing proteins in reproductive processes, and provided important guidance for genetic counseling and genetic diagnosis of male infertility.


Assuntos
Infertilidade Masculina , Camundongos Knockout , Masculino , Infertilidade Masculina/genética , Animais , Humanos , Camundongos , Espermatogênese/genética , Mitocôndrias/metabolismo , Mitocôndrias/genética , Calmodulina/metabolismo , Calmodulina/genética , Axonema/metabolismo , Mutação
14.
Technol Health Care ; 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-39031402

RESUMO

BACKGROUND: Flatfoot (pes planus) is a common foot deformity, and its causes are mainly related to age, gender, weight, and genetics. Previous studies have shown that custom-made insoles could have a positive effect in improving plantar pressure and symptoms in individuals with flexible flatfeet, but it remains to be explored whether they can still show benefits in daily walking on different slopes. OBJECTIVE: This study aims to investigate a custom-made insole based on plantar pressure redistribution and to verify its effectiveness by gait analysis on different slopes. METHODS: We recruited 10 subjects and compared the peak pressure and impulse in each area between custom-made insole (CI) and ordinary insole (OI) groups. RESULTS: The results illustrate that CI raises the pressure in T area, improves the ability of the subjects to move forward in the slope walking, which was beneficial to gait stability. CONCLUSION: The redistribution of pressure in MF and MH area is promoted to provide active protection for subjects. Meanwhile, CI could decrease the impulse in MF area during uphill and level walking, which effectively reduces the accumulation of fatigue during gait. Moreover, avoiding downhill walking could be able to protect foot from injury in daily life.

15.
J Hazard Mater ; 475: 134942, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38889462

RESUMO

Biosafety laboratories are critical in many fields. However, experimenters associated the infection risk from biological aerosols. In this study, by conducting experiments on the release and collection of bioaerosols within a typical BSL-2 + laboratory, the spatial distribution of bioaerosols was tracked. Numerical calculations were employed to obtain and visualize the airflow patterns and aerosol dispersion paths of four ventilation methods. The results indicated that equipment and tables led to uneven airflow distribution within the laboratory. The comparison results of the four evaluation indicators showed that the air age distribution of UU (Upward supply and upward return) mode and CD (Cross-supply and downward return) mode was superior, with air change efficiency values of 0.595 and 0.603, respectively. Additionally, the contaminant removal index of CD mode was 1.48, significantly higher than the other ventilation methods. The statistical results of the contaminant dispersion index also indicated that CD mode was most conducive to diluting aerosols in the spatial environment. The LD (lateral supply and downward return) mode may lead to airflow short-circuiting. The UD (upward supply and downward return) mode can provide balanced protection for laboratory. Overall, CD mode performed the best among the four ventilation methods, followed by UU mode.


Assuntos
Aerossóis , Contenção de Riscos Biológicos , Laboratórios , Ventilação , Aerossóis/análise , Contenção de Riscos Biológicos/métodos
16.
Nanoscale ; 16(22): 10597-10606, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38758161

RESUMO

Tribocatalysis is a method that converts mechanical energy into chemical energy. In this study, we synthesized tungsten bronze structured Ba0.75Sr0.25Nb1.9Ta0.1O6 ferroelectric ceramic submicron powder using a traditional solid-state route, and the powder exhibited excellent performance in tribocatalytic water splitting for hydrogen production. Under the friction stirring of three polytetrafluoroethylene (PTFE) magnetic stirring bars in pure water, the rate of hydrogen generation by the Ba0.75Sr0.25Nb1.9Ta0.1O6 ferroelectric submicron powder is 200 µmol h-1 g-1, and after 72 hours, the accumulated hydrogen production reaches 15 892.8 µmol g-1. Additionally, this ferroelectric tungsten bronze ferroelectric material also exhibits excellent tribocatalytic degradation ability toward RhB dyes, with degradation efficiency reaching 96% in 2 hours. The study of tribocatalysis based on tungsten bronze ferroelectric materials represents a significant step forward in versatile energy utilization for clean energy and environmental wastewater degradation.

17.
J Cell Physiol ; 239(5): e31251, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38634445

RESUMO

Krüppel-like factor 13 (KLF13), a zinc finger transcription factor, is considered as a potential regulator of cardiomyocyte differentiation and proliferation during heart morphogenesis. However, its precise role in the dedifferentiation of vascular smooth muscle cells (VSMCs) during atherosclerosis and neointimal formation after injury remains poorly understood. In this study, we investigated the relationship between KLF13 and SM22α expression in normal and atherosclerotic plaques by bioanalysis, and observed a significant increase in KLF13 levels in the atherosclerotic plaques of both human patients and ApoE-/- mice. Knockdown of KLF13 was found to ameliorate intimal hyperplasia following carotid artery injury. Furthermore, we discovered that KLF13 directly binds to the SM22α promoter, leading to the phenotypic dedifferentiation of VSMCs. Remarkably, we observed a significant inhibition of platelet-derived growth factor BB-induced VSMCs dedifferentiation, proliferation, and migration when knocked down KLF13 in VSMCs. This inhibitory effect of KLF13 knockdown on VCMC function was, at least in part, mediated by the inactivation of p-AKT signaling in VSMCs. Overall, our findings shed light on a potential therapeutic target for treating atherosclerotic lesions and restenosis after vascular injury.


Assuntos
Desdiferenciação Celular , Proliferação de Células , Fatores de Transcrição Kruppel-Like , Proteínas dos Microfilamentos , Proteínas Musculares , Músculo Liso Vascular , Miócitos de Músculo Liso , Proteínas Repressoras , Animais , Humanos , Masculino , Camundongos , Aterosclerose/genética , Aterosclerose/patologia , Aterosclerose/metabolismo , Lesões das Artérias Carótidas/patologia , Lesões das Artérias Carótidas/genética , Lesões das Artérias Carótidas/metabolismo , Movimento Celular/genética , Proliferação de Células/genética , Células Cultivadas , Fatores de Transcrição Kruppel-Like/metabolismo , Fatores de Transcrição Kruppel-Like/genética , Camundongos Endogâmicos C57BL , Proteínas Musculares/genética , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patologia , Miócitos de Músculo Liso/metabolismo , Miócitos de Músculo Liso/patologia , Neointima/metabolismo , Neointima/patologia , Neointima/genética , Fenótipo , Placa Aterosclerótica/patologia , Placa Aterosclerótica/metabolismo , Placa Aterosclerótica/genética , Regiões Promotoras Genéticas/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Transdução de Sinais , Proteínas de Ciclo Celular , Proteínas dos Microfilamentos/genética
18.
Dalton Trans ; 53(16): 7131-7141, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38568717

RESUMO

Spatially-ordered 1D nanocrystal-based semiconductor nanostructures possess distinct merits for photocatalytic reaction, including large surface area, fast carrier separation, and enhanced light scattering and absorption. Nevertheless, establishing a valid photo-carrier transmission channel is still crucial yet challenging for semiconductor heterostructures to realize efficient photocatalysis. In this work, spatially ordered NiOOH-ZnS/CdS heterostructures were constructed by sequential ZnS coating and NiOOH photo-deposition on multi-armed CdS, which consists of {112̄0}-faceted wurtzite nanorods grown epitaxially on {111}-faceted zinc blende core. Intriguingly, the surface photovoltage spectroscopy and PbO2 photo-deposition results suggest that the photogenerated holes of CdS were first transferred to the Zn-vacancy level of ZnS and then to NiOOH, as driven by the built-in electric field between ZnS and CdS and the hole-extracting effect of the NiOOH cocatalyst, leading to the efficient charge separation of NiOOH-ZnS/CdS. With visible-light (λ > 420 nm) irradiation, NiOOH-ZnS/CdS exhibited a distinguished H2-evolution rate of 152.20 mmol g-1 h-1 (apparent quantum efficiency of 40.9% at 420 nm), approximately 18 folds that of 3 wt% Pt-loaded CdS and much higher than that of ZnS/CdS and NiOOH-CdS counterparts as well as the most reported CdS-containing photocatalysts. Moreover, the cycling and long-term H2 generation tests manifested the outstanding photocatalyst stability of NiOOH-ZnS/CdS. The study results presented here may propel the controllable design of highly-active nanomaterials for solar conversion and utilization.

19.
J Orthop Surg Res ; 19(1): 163, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38429649

RESUMO

INTRODUCTION: This study examines bone turnover marker (BTM) variations between bone marrow and peripheral blood in osteoporotic and non-osteoporotic patients. BTMs offer insights into bone remodeling, crucial for understanding osteoporosis. METHODS: A total of 133 patients were categorized into osteoporotic and non-osteoporotic cohorts. BTMs-C-telopeptide cross-linked type 1 collagen (ß-CTX), serum osteocalcin (OC), Procollagen type I N-propeptide (P1NP), 25(OH)D-were measured in bone marrow and peripheral blood. Lumbar spine bone mineral density (BMD) was assessed. RESULTS: Osteoporotic patients exhibited elevated ß-CTX and OC levels in peripheral blood, indicating heightened bone resorption and turnover. ß-CTX levels in osteoporotic bone marrow were significantly higher. Negative correlations were found between peripheral blood ß-CTX and OC levels and lumbar spine BMD, suggesting their potential as osteoporosis severity indicators. No such correlations were observed with bone marrow markers. When analyzing postmenopausal women separately, we obtained consistent results. CONCLUSIONS: Elevated ß-CTX and OC levels in osteoporotic peripheral blood highlight their diagnostic significance. Negative ß-CTX and OC-BMD correlations underscore their potential for assessing osteoporosis severity. Discrepancies between peripheral blood and bone marrow markers emphasize the need for further exploration. This research advances our understanding of BTM clinical applications in osteoporosis diagnosis and treatment.


Assuntos
Medula Óssea , Osteoporose , Humanos , Feminino , Medula Óssea/diagnóstico por imagem , Pró-Colágeno , Biomarcadores , Osteoporose/diagnóstico por imagem , Remodelação Óssea , Osteocalcina
20.
Cell Signal ; 118: 111135, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38479555

RESUMO

BACKGROUND: Pancreatic fibrosis is one of the most important pathological features of chronic pancreatitis (CP) and pancreatic stellate cells (PSCs) are the key cells of fibrosis. As an extracellular matrix (ECM) glycoprotein, cartilage oligomeric matrix protein (COMP) is critical for collagen assembly and ECM stability and recent studies showed that COMP exert promoting fibrosis effect in the skin, lungs and liver. However, the role of COMP in activation of PSCs and pancreatic fibrosis remain unclear. We aimed to investigate the role and specific mechanisms of COMP in regulating the profibrotic phenotype of PSCs and pancreatic fibrosis. METHODS: ELISA method was used to determine serum COMP in patients with CP. Mice model of CP was established by repeated intraperitoneal injection of cerulein and pancreatic fibrosis was evaluated by Hematoxylin-Eosin staining (H&E) and Sirius red staining. Immunohistochemical staining was used to detect the expression changes of COMP and fibrosis marker such as α-SMA and Fibronectin in pancreatic tissue of mice. Cell Counting Kit-8, Wound Healing and Transwell assessed the proliferation and migration of human pancreatic stellate cells (HPSCs). Western blotting, qRT-PCR and immunofluorescence staining were performed to detect the expression of fibrosis marker, AKT and MAPK family proteins in HPSCs. RNA-seq omics analysis as well as small interfering RNA of COMP, recombinant human COMP (rCOMP), MEK inhibitors and PI3K inhibitors were used to study the effect and mechanism of COMP on activation of HPSCs. RESULTS: ELISA showed that the expression of COMP significantly increased in the serum of CP patients. H&E and Sirius red staining analysis showed that there was a large amount of collagen deposition in the mice in the CP model group and high expression of COMP, α-SMA, Fibronectin and Vimentin were observed in fibrotic tissues. TGF-ß1 stimulates the activation of HPSCs and increases the expression of COMP. Knockdown of COMP inhibited proliferation and migration of HPSCs. Further, RNA-seq omics analysis and validation experiments in vitro showed that rCOMP could significantly promote the proliferation and activation of HPSCs, which may be due to promoting the phosphorylation of ERK and AKT through membrane protein receptor CD36. rCOMP simultaneously increased the expression of α-SMA, Fibronectin and Collagen I in HPSCs. CONCLUSION: In conclusion, this study showed that COMP was up-regulated in CP fibrotic tissues and COMP induced the activation, proliferation and migration of PSCs through the CD36-ERK/AKT signaling pathway. COMP may be a potential therapeutic candidate for the treatment of CP. Interfering with the expression of COMP or the communication between COMP and CD36 on PSCs may be the next direction for therapeutic research.


Assuntos
Pancreatopatias , Pancreatite Crônica , Animais , Humanos , Camundongos , Proteína de Matriz Oligomérica de Cartilagem/metabolismo , Proteína de Matriz Oligomérica de Cartilagem/farmacologia , Proteína de Matriz Oligomérica de Cartilagem/uso terapêutico , Células Cultivadas , Colágeno Tipo I/metabolismo , Fibronectinas/metabolismo , Fibrose , Pancreatopatias/metabolismo , Células Estreladas do Pâncreas/metabolismo , Células Estreladas do Pâncreas/patologia , Pancreatite Crônica/tratamento farmacológico , Pancreatite Crônica/metabolismo , Pancreatite Crônica/patologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA