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1.
Proc Natl Acad Sci U S A ; 121(4): e2311313121, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38241436

RESUMO

Pharmacological therapies are promising interventions to slow down aging and reduce multimorbidity in the elderly. Studies in animal models are the first step toward translation of candidate molecules into human therapies, as they aim to elucidate the molecular pathways, cellular mechanisms, and tissue pathologies involved in the anti-aging effects. Trametinib, an allosteric inhibitor of MEK within the Ras/MAPK (Ras/Mitogen-Activated Protein Kinase) pathway and currently used as an anti-cancer treatment, emerged as a geroprotector candidate because it extended lifespan in the fruit fly Drosophila melanogaster. Here, we confirm that trametinib consistently and robustly extends female lifespan, and reduces intestinal stem cell (ISC) proliferation, tumor formation, tissue dysplasia, and barrier disruption in guts in aged flies. In contrast, pro-longevity effects of trametinib are weak and inconsistent in males, and it does not influence gut homeostasis. Inhibition of the Ras/MAPK pathway specifically in ISCs is sufficient to partially recapitulate the effects of trametinib. Moreover, in ISCs, trametinib decreases the activity of the RNA polymerase III (Pol III), a conserved enzyme synthesizing transfer RNAs and other short, non-coding RNAs, and whose inhibition also extends lifespan and reduces gut pathology. Finally, we show that the pro-longevity effect of trametinib in ISCs is partially mediated by Maf1, a repressor of Pol III, suggesting a life-limiting Ras/MAPK-Maf1-Pol III axis in these cells. The mechanism of action described in this work paves the way for further studies on the anti-aging effects of trametinib in mammals and shows its potential for clinical application in humans.


Assuntos
Drosophila melanogaster , Drosophila , Piridonas , Pirimidinonas , Animais , Masculino , Humanos , Feminino , Idoso , Drosophila melanogaster/genética , Envelhecimento/fisiologia , Células-Tronco/metabolismo , Mamíferos
2.
Proc Natl Acad Sci U S A ; 120(36): e2306512120, 2023 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-37639611

RESUMO

Cells migrate by adapting their leading-edge behaviors to heterogeneous extracellular microenvironments (ECMs) during cancer invasions and immune responses. Yet it remains poorly understood how such complicated dynamic behaviors emerge from millisecond-scale assembling activities of protein molecules, which are hard to probe experimentally. To address this gap, we establish a spatiotemporal "resistance-adaptive propulsion" theory based on the interactions between Arp2/3 complexes and polymerizing actin filaments and a multiscale dynamic modeling system spanning from molecular proteins to the cell. We quantitatively find that cells can accurately self-adapt propulsive forces to overcome heterogeneous ECMs via a resistance-triggered positive feedback mechanism, dominated by polymerization-induced actin filament bending and the bending-regulated actin-Arp2/3 binding. However, for high resistance regions, resistance triggers a negative feedback, hindering branched filament assembly, which adapts cellular morphologies to circumnavigate the obstacles. Strikingly, the synergy of the two opposite feedbacks not only empowers the cell with both powerful and flexible migratory capabilities to deal with complex ECMs but also enables efficient utilization of intracellular proteins by the cell. In addition, we identify that the nature of cell migration velocity depending on ECM history stems from the inherent temporal hysteresis of cytoskeleton remodeling. We also show that directional cell migration is dictated by the competition between the local stiffness of ECMs and the local polymerizing rate of actin network caused by chemotactic cues. Our results reveal that it is the polymerization force-regulated actin filament-Arp2/3 complex binding interaction that dominates self-adaptive cell migrations in complex ECMs, and we provide a predictive theory and a spatiotemporal multiscale modeling system at the protein level.


Assuntos
Citoesqueleto de Actina , Actinas , Polimerização , Movimento Celular , Citoesqueleto , Complexo 2-3 de Proteínas Relacionadas à Actina
3.
Nat Mater ; 23(6): 755-761, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38605195

RESUMO

The strength-ductility trade-off has long been a Gordian knot in conventional metallic structural materials and it is no exception in multi-principal element alloys. In particular, at ultrahigh yield strengths, plastic instability, that is, necking, happens prematurely, because of which ductility almost entirely disappears. This is due to the growing difficulty in the production and accumulation of dislocations from the very beginning of tensile deformation that renders the conventional dislocation hardening insufficient. Here we propose that premature necking can be harnessed for work hardening in a VCoNi multi-principal element alloy. Lüders banding as an initial tensile response induces the ongoing localized necking at the band front to produce both triaxial stress and strain gradient, which enables the rapid multiplication of dislocations. This leads to forest dislocation hardening, plus extra work hardening due to the interaction of dislocations with the local-chemical-order regions. The dual work hardening combines to restrain and stabilize the premature necking in reverse as well as to facilitate uniform deformation. Consequently, a superior strength-and-ductility synergy is achieved with a ductility of ~20% and yield strength of 2 GPa during room-temperature and cryogenic deformation. These findings offer an instability-control paradigm for synergistic work hardening to conquer the strength-ductility paradox at ultrahigh yield strengths.

4.
Mol Med ; 30(1): 139, 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39242993

RESUMO

BACKGROUND: Myocardial ischemia/reperfusion (I/R) injury is a common pathological process in clinical practice. Developing effective therapeutic strategies to reduce or prevent this injury is crucial. The article aimed to investigate the role and mechanism of mesencephalic astrocyte-derived neurotrophic factor (MANF) and its key subdomains in modulating myocardial I/R-induced cardiomyocyte apoptosis. METHODS: MANF stable knockout cell line and MANF mutant overexpression plasmids were constructed. The effects of MANF and mutants on apoptosis and endoplasmic reticulum (ER) stress related proteins were evaluated in hypoxia/reoxygenation-induced HL-1 cardiomyocytes by western blot, immunofluorescence, Tunel and flow cytometry. Echocardiography, ELISA, TTC and Masson were used to observe the effects of recombinant MANF protein (rMANF) on cardiac function in myocardial I/R mice. RESULTS: This study observed increased expression of MANF in both myocardial infarction patients and I/R mice. MANF overexpression in cardiomyocytes decreased ER stress-induced apoptosis, while MANF knockout exacerbated it. rMANF improved cardiac function in I/R mice by reducing injury and inflammation. This study specifically demonstrates that mutations in the α-helix of MANF were more effective in reducing ER stress and cardiomyocyte apoptosis. Mechanistically, MANF and the α-helix mutant attenuated I/R injury by inhibiting the JAK1/STAT1/NF-κB signaling pathway in addition to reducing ER stress-induced apoptosis. CONCLUSION: These findings highlight MANF and its subdomains as critical regulators of myocardial I/R injury, offering promising therapeutic targets with significant clinical implications for I/R-related diseases.


Assuntos
Apoptose , Traumatismo por Reperfusão Miocárdica , Miócitos Cardíacos , Fatores de Crescimento Neural , Transdução de Sinais , Animais , Humanos , Masculino , Camundongos , Linhagem Celular , Modelos Animais de Doenças , Estresse do Retículo Endoplasmático , Janus Quinase 1/metabolismo , Janus Quinase 1/genética , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/genética , Miócitos Cardíacos/metabolismo , Fatores de Crescimento Neural/metabolismo , Fatores de Crescimento Neural/genética , NF-kappa B/metabolismo , Fator de Transcrição STAT1/metabolismo
5.
Cancer Cell Int ; 24(1): 129, 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38582841

RESUMO

BACKGROUND: The objective of this study was to determine the role and regulatory mechanism of miR-380 in cholangiocarcinoma. METHODS: The TargetScan database and a dual-luciferase reporter assay system were used to determine if LIS1 was a target gene of miR-380. The Cell Counting Kit 8 assay, flow cytometry, and Transwell assay were used to detect the effects of miR-380 and LIS1 on the proliferation, S-phase ratio, and invasiveness of HCCC-9810/HuCCT1/QBC939 cells. Western blotting was used to determine the effect of miR-380 on MMP-2/p-AKT. Immunohistochemistry detected the regulatory effect of miR-380 on the expression of MMP-2/p-AKT/LIS1. RESULTS: Expression of miR-380 in cholangiocarcinoma was decreased but expression of LIS1 was increased. LIS1 was confirmed to be a target gene of miR-380. Transfection with miR-380 mimics inhibited the proliferation, S-phase arrest, and invasion of HCCC-9810/HuCCT1/QBC939 cells, and LIS1 reversed these inhibitory effects. miR-380 inhibitor promoted proliferation, S-phase ratio, and invasiveness of HCCC-9810/HuCCT1/QBC939 cells. si-LIS1 salvaged the promotive effect of miR-380 inhibitor. Overexpression of miR-380 inhibited expression of MMP-2/p-AKT/LIS1, but miR-380 inhibitor promoted their expression. CONCLUSION: An imbalance of miR-380 expression is closely related to cholangiocarcinoma, and overexpression of miR-380 inhibits the expression of MMP-2/p-AKT by directly targeting LIS1.

6.
FASEB J ; 37(5): e22933, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37093709

RESUMO

FURIN, a member of the mammalian proprotein convertases (PCs) family, can promote the proteolytic maturation of proproteins. It has been shown that FURIN plays an important role in the progression of atherosclerosis (AS). Current evidence indicates that autophagy widely participates in atherogenesis. This study aimed to explore whether FURIN could affect atherogenesis via autophagy. The effect of FURIN on autophagy was studied using aortic tissues from aortic dissection patients who had BENTALL surgery, as well as macrophages and ApoE-/- mice. In atherosclerotic plaques of aortic tissues from patients, FURIN expression and autophagy were elevated. In macrophages, FURIN-shRNA and FURIN-overexpression lentivirus were used to intervene in FURIN expression. The results showed that FURIN overexpression accelerated LC3 formation in macrophages during the autophagosome formation phase. Furthermore, FURIN-induced autophagy resulted in lower lipid droplet concentrations in macrophages. The western blot revealed that FURIN regulated autophagy via the AMPK/mTOR/ULK1/PI3KIII signaling pathway. In vivo, FURIN overexpression resulted in increased macrophage LC3 formation in ApoE-/- mice atherosclerotic plaques, confirming that FURIN could inhibit the progression of AS by promoting macrophage autophagy. The present study demonstrated that FURIN suppressed the progression of AS by promoting macrophage autophagy via the AMPK/mTOR/ULK1/PI3KIII signaling pathway, which attenuated atherosclerotic lesion formation. Based on this data, current findings add to our understanding of the complexity of AS.


Assuntos
Aterosclerose , Placa Aterosclerótica , Camundongos , Animais , Placa Aterosclerótica/metabolismo , Furina/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Camundongos Knockout para ApoE , Aterosclerose/metabolismo , Macrófagos/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Autofagia/genética , Apolipoproteínas E/genética , Mamíferos/metabolismo
7.
Inflamm Res ; 73(6): 1033-1046, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38630134

RESUMO

OBJECTIVE: Sepsis-induced cardiomyopathy (SICM) is a life-threatening complication. Phospholipase D2 (PLD2) is crucial in mediating inflammatory reactions and is associated with the prognosis of patients with sepsis. Whether PLD2 is involved in the pathophysiology of SICM remains unknown. This study aimed to investigate the effect of PLD2 knockout on SICM and to explore potential mechanisms. METHODS: The SICM model was established using cecal ligation and puncture in wild-type and PLD2-knockout mice and lipopolysaccharide (LPS)-induced H9C2 cardiomyocytes. Transfection with PLD2-shRNA lentivirus and a PLD2 overexpression plasmid were used to interfere with PLD2 expression in H9C2 cells. Cardiac pathological alterations, cardiac function, markers of myocardial injury, and inflammatory factors were used to evaluate the SICM model. The expression of pyroptosis-related proteins (NLRP3, cleaved caspase 1, and GSDMD-N) was assessed using western blotting, immunofluorescence, and immunohistochemistry. RESULTS: SICM mice had myocardial tissue damage, increased inflammatory response, and impaired heart function, accompanied by elevated PLD2 expression. PLD2 deletion improved cardiac histological changes, mitigated cTNI production, and enhanced the survival of the SICM mice. Compared with controls, PLD2-knockdown H9C2 exhibits a decrease in inflammatory markers and lactate dehydrogenase production, and scanning electron microscopy results suggest that pyroptosis may be involved. The overexpression of PLD2 increased the expression of NLRP3 in cardiomyocytes. In addition, PLD2 deletion decreased the expression of pyroptosis-related proteins in SICM mice and LPS-induced H9C2 cells. CONCLUSION: PLD2 deletion is involved in SICM pathogenesis and is associated with the inhibition of the myocardial inflammatory response and pyroptosis through the NLRP3/caspase 1/GSDMD pathway.


Assuntos
Cardiomiopatias , Caspase 1 , Camundongos Knockout , Miócitos Cardíacos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Fosfolipase D , Piroptose , Sepse , Animais , Masculino , Camundongos , Ratos , Cardiomiopatias/etiologia , Cardiomiopatias/genética , Caspase 1/metabolismo , Caspase 1/genética , Linhagem Celular , Gasderminas , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Lipopolissacarídeos , Camundongos Endogâmicos C57BL , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteínas de Ligação a Fosfato/genética , Proteínas de Ligação a Fosfato/metabolismo , Fosfolipase D/genética , Fosfolipase D/metabolismo , Sepse/complicações , Sepse/genética , Transdução de Sinais
8.
J Gastroenterol Hepatol ; 39(5): 908-919, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38323685

RESUMO

BACKGROUND AND AIM: A growing number of studies have demonstrated that neoadjuvant chemotherapy can improve the prognosis of patients with resectable colorectal liver metastases (CRLM). However, the routine use of postoperative adjuvant chemotherapy (POAC) for patients with CRLM after simultaneous resection remains controversial. This retrospective study investigated the impact of POAC on outcomes in patients with CRLM who underwent simultaneous resection of colorectal cancer tumors and liver metastases using propensity score matching (PSM) analysis. METHODS: From January 2009 to November 2020, patients with CRLM who underwent simultaneous resection were retrospectively enrolled. The confounding factors and selection bias were adjusted by 2:1 PSM. Patients were stratified into the POAC and non-POAC groups. Kaplan-Meier curves were utilized to compare overall survival (OS) and progression-free survival (PFS) between the groups. Univariate and multivariate Cox regression analyses were used to identify independent clinicopathological factors before and after PSM analysis. The utility of the model was evaluated using receiver operating characteristic (ROC) and calibration curves after PSM analysis. RESULTS: In total, 478 patients with resectable CRLM were enrolled and assigned to the POAC (n = 212, 60.9%) or non-POAC group (n = 136, 39.1%). After 2:1 PSM, there was no significant bias between the groups. Kaplan-Meier survival analysis revealed a significant effect of POAC on OS (P < 0.001) but not PFS. Multivariate Cox regression analysis identified T stage (T3-T4), lymph node metastasis, radiofrequency ablation during surgery, operative time ≥ 325 min, and the receipt of postoperative adjuvant chemotherapy (hazard ratio = 0.447, 95% confidence interval = 0.312-0.638, P < 0.001) as independent prognostic factors for OS. The areas under the ROC curves for the nomogram model for predicting 1-, 3-, and 5-year survival were 0.653, 0.628, and 0.678, respectively. Subgroups analysis suggested that POAC can enhance OS in patients with resectable CRLM with either low (1-2, P < 0.001) or high clinical risk scores (3-5, P = 0.020). CONCLUSIONS: Overall, this study identified POAC as a prognostic factor to predict OS in patients with CRLM undergoing simultaneous resection.


Assuntos
Neoplasias Colorretais , Hepatectomia , Neoplasias Hepáticas , Humanos , Neoplasias Colorretais/patologia , Neoplasias Colorretais/mortalidade , Quimioterapia Adjuvante , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/cirurgia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/terapia , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Retrospectivos , Idoso , Pontuação de Propensão , Taxa de Sobrevida , Fatores de Tempo , Resultado do Tratamento
9.
BMC Cardiovasc Disord ; 24(1): 138, 2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38431594

RESUMO

AIMS: Recent studies have indicated an association between intestinal flora and lipids. However, observational studies cannot indicate causality. In this study, we aimed to investigate the potentially causal relationships between the intestinal flora and blood lipids. METHODS: We performed a bidirectional two-sample Mendelian Randomization (MR) analysis to investigate the causal relationship between intestinal flora and blood lipids. Summary statistics of genome-wide association studies (GWASs) for the 211 intestinal flora and blood lipid traits (n = 5) were obtained from public datasets. Five recognized MR methods were applied to assess the causal relationship with lipids, among which, the inverse-variance weighted (IVW) regression was used as the primary MR method. A series of sensitivity analyses were performed to test the robustness of the causal estimates. RESULTS: The results indicated a potential causal association between 19 intestinal flora and dyslipidemia in humans. Genus Ruminococcaceae, Christensenellaceae, Parasutterella, Terrisporobacter, Parabacteroides, Class Erysipelotrichia, Family Erysipelotrichaceae, and order Erysipelotrichales were associated with higher dyslipidemia, whereas genus Oscillospira, Peptococcus, Ruminococcaceae UCG010, Ruminococcaceae UCG011, Dorea, and Family Desulfovibrionaceae were associated with lower dyslipidemia. After using the Bonferroni method for multiple testing correction, Only Desulfovibrionaceae [Estimate = -0.0418, 95% confidence interval [CI]: 0.9362-0.9826, P = 0.0007] exhibited stable and significant negative associations with ApoB levels. The inverse MR analysis did not find a significant causal effect of lipids on the intestinal flora. Additionally, no significant heterogeneity or horizontal pleiotropy for IVs was observed in the analysis. CONCLUSION: The study suggested a causal relationship between intestinal flora and dyslipidemia. These findings will provide a meaningful reference to discover dyslipidemia for intervention to address the problems in the clinic.


Assuntos
Aterosclerose , Dislipidemias , Microbioma Gastrointestinal , Humanos , Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Aterosclerose/diagnóstico , Aterosclerose/epidemiologia , Aterosclerose/genética
10.
Eur J Pediatr ; 183(9): 4029-4039, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38955847

RESUMO

The objective of this study was to examine the utility of the acceleration index observed in an electrocardiogram (ECG) for the prediction of the effectiveness of orthostatic training in pediatric patients diagnosed with postural orthostatic tachycardia syndrome (POTS). This investigation focused on children diagnosed with POTS and undergoing orthostatic training at the Department of Pediatrics of Peking University First Hospital from January 2012 to October 2022. Specifically, patients hospitalized from January 2012 to December 2019 were included in the training set (54 cases), while those hospitalized from January 2020 to October 2022 were included in the external validation set (37 cases). All children received a 3-month orthostatic training, and the baseline symptom score (SS) was calculated in agreement with the pretreatment orthostatic intolerance symptom frequency. Additionally, we determined post-treatment SS during follow-up via telephone after the 3-month treatment. Children with a decrease in post-treatment SS by ≥ 50% of the baseline were considered as responders; otherwise, they were considered as non-responders. Demographic data (age, sex, and body mass index), hemodynamic parameters (supine blood pressure, time to achieve a positive standing test, maximum increase in heart rate during the standing test, maximal heart rate reached during the standing test, and blood pressure at the point of maximal heart rate during the standing test), and electrocardiographic parameters (RR interval in the supine position, shortest RR interval in the upright position, and acceleration index) were collected from all the children prior to treatment. Univariate and multivariate regression analysis were conducted to investigate factors associated with the efficacy of orthostatic training. The predictive value of these indicators for the therapeutic effectiveness of orthostatic training in children with POTS was evaluated using receiver operating characteristic (ROC) analysis, and the indicators were validated using the validation set. Among the 54 children in the training set, 28 responded to orthostatic training, and 26 were nonresponsive. Compared with the non-responders, the responders demonstrated a significant reduction in acceleration index (P < 0.01). The ROC curve for the predictive value of the acceleration index exhibited an area under the curve = 0.81 (95% confidence interval: 0.685-0.926). With the acceleration index threshold < 27.93%, the sensitivity and specificity in the prediction of orthostatic training efficacy among children with POTS were 85.7% and 69.2%, respectively. The external validation results demonstrated that using acceleration index < 27.93% as the threshold, the sensitivity, specificity, and accuracy of predicting orthostatic training efficacy among children with POTS were 89.5%, 77.8%, and 83.8%, respectively. CONCLUSIONS: Electrocardiographic acceleration index can be used to predict the effectiveness of orthostatic training in treating children with POTS. WHAT IS KNOWN: • Postural orthostatic tachycardia syndrome (POTS) is a chronic orthostatic intolerance involving multiple mechanisms. Autonomic dysfunction is one of the main mechanisms of POTS in children and could be treated with orthostatic training. • In order to improve the efficacy of orthostatic training in children with POTS, it is particularly important to identify the patients with autonomic dysfunction as the main mechanism before the treatment. WHAT IS NEW: • We found acceleration index of the electrocardiogram (ECG) can be used as a satisfactory index to predict the efficacy of orthostatic training in the treatment of POTS in children. • Using the acceleration index to predict the efficacy of orthostatic training on POTS in children is easy to be popularized in hospitals at all levels because it is non-invasive, convenient, and not expensive.


Assuntos
Eletrocardiografia , Síndrome da Taquicardia Postural Ortostática , Humanos , Síndrome da Taquicardia Postural Ortostática/terapia , Síndrome da Taquicardia Postural Ortostática/fisiopatologia , Síndrome da Taquicardia Postural Ortostática/diagnóstico , Masculino , Feminino , Criança , Eletrocardiografia/métodos , Resultado do Tratamento , Adolescente , Frequência Cardíaca/fisiologia , Aceleração , Estudos Retrospectivos , Valor Preditivo dos Testes
11.
Orthod Craniofac Res ; 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39225036

RESUMO

BACKGROUND: Orthodontically induced inflammatory root resorption (OIIRR) is one of the most important side effects of orthodontic treatment. Low-level laser therapy (LLLT) is a useful way to reduce the orthodontic treatment duration and may have some effect on preventing and repairing OIIRR. However, the specific effects of LLLT on OIIRR remain unknown. OBJECTIVE: Our research aimed to evaluate the Dentin Sialophosphoprotein (DSPP) expression level and root resorption volume during treatment and retention to explore the role of LLLT in preventing and repairing OIIRR. METHODS: Thirty-seven 6-week-old male Sprague-Dawley rats were selected to establish an OIIRR model; the rats were divided into Group B (blank), Group F (force), Group F(LLLT) (force and LLLT), Group F+R (force and retention) and Group F+R(LLLT) (force, retention and LLLT). The root resorption volume of the distal buccal root and mesial root in the maxillary left first molar was calculated by micro-CT, and the DSPP expression level on the compression side of the periodontal ligament was analysed by immunohistochemical staining. RESULTS: The resorption volume in Group F was greater than that in Group F(LLLT). For the mesial root, the volume in Group F was greater than that in Groups F+R and F+R(LLLT). For the distal buccal root, the volume in Groups F and F+R was greater than that in Group F+R(LLLT). The DSPP level in Group F(LLLT) was greater than that in Group F and there was no difference between Groups F+R and F+R(LLLT). CONCLUSIONS: LLLT has a certain preventive effect and a limited reparative effect on OIIRR in rats.

12.
Orthod Craniofac Res ; 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39350680

RESUMO

OBJECTIVES: Rapid maxillary expansion (RME) is a widely used technique to treat maxillary transverse deficiency. Piezo1 is a cation channel that is activated by mechanical force and regulates bone formation. This study aims to elucidate the role of Piezo1 in bone remodelling during the RME process. MATERIALS AND METHODS: In this study, the periosteal-derived stem cells (PDSCs) were cultured and stretched by the Flexcell system. The effects of Piezo1 on osteogenesis were assessed via RNA sequencing, real-time quantitative PCR, and western blot analyses. Moreover, for in vivo analyses, the rat RME model was established. The function of Piezo1 in mid-palatal suture bone remodelling was evaluated using micro-CT, haematoxylin-eosin (HE) staining, and immunohistochemistry analyses. RESULTS: It was revealed that under tension force, the osteogenic factors (Runt-related transcription factor 2, Osterix, and Alkaline Phosphatase) and Ca2+/calmodulin -dependent protein kinase (CaMKII) were significantly enhanced in PDSCs over time. Furthermore, these were also upregulated in the RME model with the expansion of the mid-palatal suture. However, Piezo1 inhibition by Grammostola spatulata mechanotoxin 4 downregulated the levels of these factors in the RME model. CONCLUSIONS: This study indicated that Piezo1 is associated with the osteogenesis of PDSCs and bone remodelling in the RME process. CaMKII might also participate in this process.

13.
Ecotoxicol Environ Saf ; 277: 116342, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38657457

RESUMO

Pyrethroids (PYs) are widely applied pesticides whose residues pose potential health risks. This review describes current knowledge on PY chemical properties, usage patterns, environmental and food contamination, and human exposure models. It evaluates life cycle assessment (LCA), chemical alternatives assessment (CAA), and high-throughput screening (HTS) as tools for pesticide policy. Despite efforts to mitigate PY presence, their pervasive residues in the environment and food persist. And the highest concentrations ranged from 54,360 to 80,500 ng/L in water samples from agricultural fields. Food processing techniques variably reduce PY levels, yet no method guarantees complete elimination. This review provides insights into the fates and exposure pathways of PY residues in agriculture and food, and highlights the necessity for improved PY management and alternative practices to safeguard health and environment.


Assuntos
Contaminação de Alimentos , Resíduos de Praguicidas , Piretrinas , Humanos , Agricultura , Exposição Ambiental/análise , Monitoramento Ambiental , Contaminação de Alimentos/análise , Resíduos de Praguicidas/análise , Piretrinas/análise , Piretrinas/toxicidade , Medição de Risco , Poluentes Químicos da Água/análise
14.
Ren Fail ; 46(2): 2385724, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39282735

RESUMO

OBJECTIVES: Effectiveness of nirmatrelvir/ritonavir (NR) in kidney transplant recipients (KTRs) infected COVID-19 for more than 5 days has not been evaluated. METHODS: In this multicenter retrospective study, 85 KTRs with COVID-19 were enrolled, including 50 moderate, 21 severe, and 14 critical patients. RESULTS: The median time from onset to starting NR treatment was 14 (IQR, 11-19) days. Before NR treatment, 96.5% patients reduced use of antimetabolites. They also stopped using calcineurin inhibitors (CNI) 12-24 hours before NR treatment, with CNI concentrations well-controlled during NR treatment. The use of intravenous corticosteroids increased with COVID-19 severity. The median time to reach viral negative conversion was 5 (IQR, 4-8) days for all patients. For moderate and severe COVID-19 patients, they had a low rate of ICU admission (1.4%), exacerbation requiring upgraded oxygen therapy (5.6%), and dialysis (2.8%); no intubation and mechanical ventilation, and no deaths were observed. Patients with critical COVID-19 had a low mortality rate (7.1%). CONCLUSIONS: A regimen including NR for clearing SARS-CoV-2 along with reducing immunosuppressants and using intravenous corticosteroids is associated with lower rates of exacerbation and mortality in KTRs who have moderate to critical SARS-CoV-2 infection and the virus still present after 5 days.


Assuntos
Antivirais , Tratamento Farmacológico da COVID-19 , Transplante de Rim , Ritonavir , Humanos , Ritonavir/uso terapêutico , Ritonavir/administração & dosagem , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Retrospectivos , Antivirais/uso terapêutico , Antivirais/administração & dosagem , Idoso , COVID-19/mortalidade , COVID-19/complicações , SARS-CoV-2 , Combinação de Medicamentos , Imunossupressores/administração & dosagem , Imunossupressores/efeitos adversos , Imunossupressores/uso terapêutico , Resultado do Tratamento , Lopinavir/uso terapêutico , Lopinavir/administração & dosagem , Adulto , Transplantados/estatística & dados numéricos , Hospitalização/estatística & dados numéricos
15.
Ren Fail ; 46(1): 2314630, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38345067

RESUMO

BACKGROUND: No study has validated, compared and adapted scoring systems for prognosis prediction based on donor kidney core biopsy (CB), with less glomeruli than wedge biopsy. METHODS: A total of 185 donor kidney CB specimens were reviewed using seven scoring systems. The association between the total score, item scores, score-based grading, and allograft prognosis was investigated. In specimens with less than ten glomeruli (88/185, 47.6%), scoring systems were modified by adjusting weights of the item scores. RESULTS: The Maryland aggregate pathology index (MAPI) score-based grading and periglomerular fibrosis (PGF) associated with delayed graft function (DGF) (Grade: OR = 1.59, p < 0.001; PGF: OR = 1.06, p = 0.006). Total score, score-based grading and chronic lesion score in scoring systems associated with one-year and 3-year eGFR after transplantation. Total-score-based models had similar predictive capacities for eGFR in all scoring systems, except MAPI and Ugarte. Score of glomerulosclerosis (GS), interstitial fibrosis (IF), tubular atrophy (TA), and arteriolar hyalinosis (AH) had good eGFR predictive capacities. In specimens with less than ten glomeruli, modified scoring systems had better eGFR predictive capacities than original scoring systems. CONCLUSIONS: Scoring systems could predict allograft prognosis in paraffin-embedded CB with ten more glomeruli. A simple and pragmatic scoring system should include GS, IF, TA and AH, with weights assigned based on predictive capacity for prognosis. Replacing GS scores with tubulointerstitial scores could significantly improve the predictive capacity of eGFR. The conclusion should be further validated in frozen section.


Assuntos
Nefropatias , Transplante de Rim , Humanos , Rim/patologia , Prognóstico , Inclusão em Parafina , Nefropatias/patologia , Biópsia , Fibrose
16.
Sensors (Basel) ; 24(11)2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38894103

RESUMO

In answer to the demand for high sensitivity and miniaturization of ultra-high frequency (UHF) sensors for partial discharge (PD) detection in power equipment, this paper proposes research on miniaturized UHF-sensing technology for PD detection in power equipment based on symmetric cut theory. The symmetric cut theory is applied for the first time to the miniaturization of PD UHF sensors for power equipment. A planar monopole UHF sensor with a size of only 70 mm × 70 mm × 1.6 mm is developed using an exponential asymptotic feed line approach, which is a 50% size reduction. The frequency-response characteristics of the sensor are simulated, optimized and tested; the results show that the standing wave ratio of the sensor developed in this paper is less than 2 in the frequency band from 427 MHz to 1.54 GHz, and less than 5 in the frequency band from 300 MHz to 1.95 GHz; in the 300 MHz~1.5 GHz band; the maximum and average gains of the sensor E-plane are 4.76 dB and 1.02 dB, respectively. Finally, the PD simulation experiment platform for power equipment is built to test the sensor's sensing performance; the results show that the sensor can effectively detect the PD signals; the sensing sensitivity is improved by about 95% relative to an elliptical monopole UHF sensor.

17.
BMC Oral Health ; 24(1): 785, 2024 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-38997686

RESUMO

BACKGROUND: The number of adult orthodontic patients is increasing, and studies have shown that autophagy is involved in regulating orthodontic tooth movement and plays an important role in aging-related changes. Therefore, we aimed to explore the role of autophagy in aging-related changes during orthodontic tooth movement by establishing a rat orthodontic tooth movement model. METHODS: Forty-five 6-week-old and sixty-five 8-month-old male Sprague-Dawley rats were selected to represent adolescents and adults and establish orthodontic tooth movement model. They were sacrificed on days 0,1,3,7 and 14. Immunohistochemistry, immunofluorescence and tartrate resistant acid phosphatase (TRAP) staining were applied to measure the expression level of osteogenesis, autophagy, aging factors and osteoclast number in periodontal membrane of left upper first molar during orthodontic tooth movement. Then, we regulated the autophagy level by injecting autophagy activator rapamycin during orthodontic tooth movement and measured these factors and tooth movement distance by micro-computed tomography. RESULTS: Aging factor levels in the periodontal membrane were higher in adult rats than in adolescent rats and the autophagy factor levels were lower. The levels of osteogenic factors were lower on the tension side in adult rats than in adolescent rats. The peak osteoclast number on the pressure side occurred later in adult rats than in adolescent rats. The injection of rapamycin increased autophagy, accelerated orthodontic tooth movement in adult rats, and reduced the levels of aging factors. The levels of osteogenic factors were higher and reached those in adolescent rats at some time points. The number of osteoclasts increased significantly in the early stage. CONCLUSIONS: Autophagy may play a substantial role in regulating aging-related changes in orthodontic tooth movement.


Assuntos
Envelhecimento , Autofagia , Osteoclastos , Ratos Sprague-Dawley , Técnicas de Movimentação Dentária , Animais , Autofagia/fisiologia , Masculino , Ratos , Envelhecimento/fisiologia , Envelhecimento/patologia , Microtomografia por Raio-X , Sirolimo/farmacologia , Osteogênese/fisiologia , Fosfatase Ácida Resistente a Tartarato/metabolismo , Dente Molar
18.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 55(1): 74-80, 2024 Jan 20.
Artigo em Zh | MEDLINE | ID: mdl-38322523

RESUMO

Objective: To explore the mechanobiological mechanism of fluid shear force (FSF) on the protection, injury, and destruction of the structure and function of the blood-brain barrier (BBB) under normal physiological conditions, ischemic hypoperfusion, and postoperative hyperperfusion conditions. BBB is mainly composed of brain microvascular endothelial cells. Rat brain microvascular endothelial cells (rBMECs) were used as model cells to conduct the investigation. Methods: rBMECs were seeded at a density of 1×105 cells/cm2 and incubated for 48 h. FSF was applied to the rBMECs at 0.5, 2, and 20 dyn/cm2, respectively, simulating the stress BBB incurs under low perfusion, normal physiological conditions, and high FSF after bypass grafting when there is cerebral vascular stenosis. In addition, a rBMECs static culture group was set up as the control (no force was applied). Light microscope, scanning electron microscope (SEM), and laser confocal microscope (LSCM) were used to observe the changes in cell morphology and cytoskeleton. Transmission electron microscope (TEM) was used to observe the tight junctions. Immunofluorescence assay was performed to determine changes in the distribution of tight junction-associated proteins claudin-5, occludin, and ZO-1 and adherens junction-associated proteins VE-cadherin and PECAM-1. Western blot was performed to determine the expression levels of tight junction-associated proteins claudin-5, ZO-1, and JAM4, adherens junction-associated protein VE-cadherin, and key proteins in Rho GTPases signaling (Rac1, Cdc42, and RhoA) under FSF at different intensities. Results: Microscopic observation showed that the cytoskeleton exhibited disorderly arrangement and irregular orientation under static culture and low shear force (0.5 dyn/cm2). Under normal physiological shear force (2 dyn/cm2), the cytoskeleton was rearranged in the orientation of the FSF and an effective tight junction structure was observed between cells. Under high shear force (20 dyn/cm2), the intercellular space was enlarged and no effective tight junction structure was observed. Immunofluorescence results showed that, under low shear force, the gap between the cells decreased, but there was also decreased distribution of tight junction-associated proteins and adherens junction-associated proteins at the intercellular junctions. Under normal physiological conditions, the cells were tightly connected and most of the tight junction-associated proteins were concentrated at the intercellular junctions. Under high shear force, the gap between the cells increased significantly and the tight junction and adherens junction structures were disrupted. According to the Western blot results, under low shear force, the expression levels of claudin-5, ZO-1, and VE-cadherin were significantly up-regulated compared with those of the control group (P<0.05). Under normal physiological shear force, claudin-5, ZO-1, JAM4, and VE-cadherin were highly expressed compared with those of the control group (P<0.05). Under high shear force, the expressions of claudin-5, ZO-1, JAM4, and VE-cadherin were significantly down-regulated compared with those of the normal physiological shear force group (P<0.05). Under normal physiological shear force, intercellular expressions of Rho GTPases proteins (Rac1, Cdc42, and RhoA) were up-regulated and were higher than those of the other experimental groups (P<0.05). The expressions of Rho GTPases under low and high shear forces were down-regulated compared with that of the normal physiological shear force group (P<0.05). Conclusion: Under normal physiological conditions, FSF helps maintain the integrity of the BBB structure, while low or high shear force can damage or destroy the BBB structure. The regulation of BBB by FSF is closely related to the expression and distribution of tight junction-associated proteins and adherens junction-associated proteins.


Assuntos
Barreira Hematoencefálica , Células Endoteliais , Ratos , Animais , Claudina-5/metabolismo , Encéfalo/metabolismo , Proteínas rho de Ligação ao GTP/metabolismo
19.
Cancer Cell Int ; 23(1): 46, 2023 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-36927769

RESUMO

Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide. Its invasiveness and ability to metastasize contributes to an extremely high patient mortality. However, the molecular mechanisms that underlie the characteristics of HCC progression are not well understood. BRF2 has been shown to be an oncogene in a number of tumors; however, its role in HCC has not yet been thoroughly examined. In this study, we identified and validated BRF2 as an oncogene in HCC, providing a new insight into HCC pathogenesis and therapeutic possibilities. We showed that BRF2 expression was significantly upregulated in HCC cell lines and tissues, while BRF2 depletion suppressed HCC metastasis and invasion. We then examined the upstream regulation of BRF2 and identified miR-409-3p as being predicted to bind to the 3' UTR of BRF2. We used a luciferase activity assay and functional verification to show that BRF2 is downregulated by miR-409-3p. Finally, we used bioinformatic analysis to show that BRF2 may be related to early HCC development through the Wnt/ß-catenin signaling pathway.

20.
Langmuir ; 39(37): 13090-13102, 2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37669076

RESUMO

Gaseous thallium (Tl) pollution events, primarily caused by non-ferrous mineral refineries and fossil fuel combustion, have increased over the past few decades. To prevent gaseous Tl distribution from flue gas, MnO2/CeO2@HKUST-1 (MCH) was synthesized and found to achieve a gaseous Tl(I) removal level of up to 90% at 423 K, a weight hourly space velocity (WHSV) of 2000 h-1/mL with an Mn dose of 10%, maintained over 10 h. The best Mn/Ce ratio was found to be 9:1. To further investigate surface kinetic behavior, four commonly used kinetic models were applied, including the Eley-Rideal (ER) model, Langmuir-Hinshelwood (LH) model, Mars-van Krevelen (MVK) model, and pseudo-first-order (PFO) model. While the ER and LH models had the slightest deviation, the MVK model was the most reliable. The CatMAP software was also used to match the simulation deviation. This work demonstrated the Tl removal mechanism and provided insights into the accuracy of kinetic models on minor-radius heavy metal. Thus, this research may help promote the design of reactors, heavy metal removal rates, and flue gas purification technology selection.

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