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1.
J Cell Sci ; 136(21)2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37815466

RESUMO

Connections between the nucleus and the cytoskeleton are important for positioning and division of the nucleus. In most eukaryotes, the linker of nucleoskeleton and cytoskeleton (LINC) complex spans the outer and inner nuclear membranes and connects the nucleus to the cytoskeleton. In opisthokonts, it is composed of Klarsicht, ANC-1 and Syne homology (KASH) domain proteins and Sad1 and UNC-84 (SUN) domain proteins. Given that the nucleus is positioned at the posterior pole of Toxoplasma gondii, we speculated that apicomplexan parasites must have a similar mechanism that integrates the nucleus and the cytoskeleton. Here, we identified three UNC family proteins in the genome of the apicomplexan parasite T. gondii. Whereas the UNC-50 protein TgUNC1 localised to the Golgi and appeared to be not essential for the parasite, the SUN domain protein TgSLP2 showed a diffuse pattern throughout the parasite. The second SUN domain protein, TgSLP1, was expressed in a cell cycle-dependent manner and was localised close to the mitotic spindle and, more detailed, at the kinetochore. We demonstrate that conditional knockout of TgSLP1 leads to failure of nuclear division and loss of centrocone integrity.


Assuntos
Parasitos , Toxoplasma , Animais , Toxoplasma/genética , Membrana Nuclear/metabolismo , Fuso Acromático , Divisão do Núcleo Celular
2.
Development ; 149(22)2022 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-36264221

RESUMO

The evolutionarily conserved Glycogen Synthase Kinase 3ß (GSK3ß), a negative regulator of microtubules, is crucial for neuronal polarization, growth and migration during animal development. However, it remains unknown whether GSK3ß regulates neuronal pruning, which is a regressive process. Here, we report that the Drosophila GSK3ß homologue Shaggy (Sgg) is cell-autonomously required for dendrite pruning of ddaC sensory neurons during metamorphosis. Sgg is necessary and sufficient to promote microtubule depolymerization, turnover and disassembly in the dendrites. Although Sgg is not required for the minus-end-out microtubule orientation in dendrites, hyperactivated Sgg can disturb the dendritic microtubule orientation. Moreover, our pharmacological and genetic data suggest that Sgg is required to promote dendrite pruning at least partly via microtubule disassembly. We show that Sgg and Par-1 kinases act synergistically to promote microtubule disassembly and dendrite pruning. Thus, Sgg and Par-1 might converge on and phosphorylate a common downstream microtubule-associated protein(s) to disassemble microtubules and thereby facilitate dendrite pruning.


Assuntos
Proteínas de Drosophila , Drosophila , Animais , Drosophila/genética , Proteínas de Drosophila/genética , Glicogênio Sintase Quinase 3 beta/genética , Dendritos/genética , Células Receptoras Sensoriais , Microtúbulos , Plasticidade Neuronal/genética , Drosophila melanogaster/genética
3.
Cereb Cortex ; 34(1)2024 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-38061699

RESUMO

Abnormal processes of learning from prediction errors, i.e. the discrepancies between expectations and outcomes, are thought to underlie motivational impairments in schizophrenia. Although dopaminergic abnormalities in the mesocorticolimbic reward circuit have been found in patients with schizophrenia, the pathway through which prediction error signals are processed in schizophrenia has yet to be elucidated. To determine the neural correlates of prediction error processing in schizophrenia, we conducted a meta-analysis of whole-brain neuroimaging studies that investigated prediction error signal processing in schizophrenia patients and healthy controls. A total of 14 studies (324 schizophrenia patients and 348 healthy controls) using the reinforcement learning paradigm were included. Our meta-analysis showed that, relative to healthy controls, schizophrenia patients showed increased activity in the precentral gyrus and middle frontal gyrus and reduced activity in the mesolimbic circuit, including the striatum, thalamus, amygdala, hippocampus, anterior cingulate cortex, insula, superior temporal gyrus, and cerebellum, when processing prediction errors. We also found hyperactivity in frontal areas and hypoactivity in mesolimbic areas when encoding prediction error signals in schizophrenia patients, potentially indicating abnormal dopamine signaling of reward prediction error and suggesting failure to represent the value of alternative responses during prediction error learning and decision making.


Assuntos
Imageamento por Ressonância Magnética , Esquizofrenia , Humanos , Imageamento por Ressonância Magnética/métodos , Esquizofrenia/diagnóstico por imagem , Reforço Psicológico , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Recompensa , Dopamina/metabolismo
4.
Proc Natl Acad Sci U S A ; 119(37): e2121848119, 2022 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-36067324

RESUMO

Refractory carbides are attractive candidates for support materials in heterogeneous catalysis because of their high thermal, chemical, and mechanical stability. However, the industrial applications of refractory carbides, especially silicon carbide (SiC), are greatly hampered by their low surface area and harsh synthetic conditions, typically have a very limited surface area (<200 m2 g-1), and are prepared in a high-temperature environment (>1,400 °C) that lasts for several or even tens of hours. Based on Le Chatelier's principle, we theoretically proposed and experimentally verified that a low-pressure carbothermal reduction (CR) strategy was capable of synthesizing high-surface area SiC (569.9 m2 g-1) at a lower temperature and a faster rate (∼1,300 °C, 50 Pa, 30 s). Such high-surface area SiC possesses excellent thermal stability and antioxidant capacity since it maintained stability under a water-saturated airflow at 650 °C for 100 h. Furthermore, we demonstrated the feasibility of our strategy for scale-up production of high-surface area SiC (460.6 m2 g-1), with a yield larger than 12 g in one experiment, by virtue of an industrial viable vacuum sintering furnace. Importantly, our strategy is  also applicable to the rapid synthesis of refractory metal carbides (NbC, Mo2C, TaC, WC) and even their emerging high-entropy carbides (VNbMoTaWC5, TiVNbTaWC5). Therefore, our low-pressure CR method provides an alternative strategy, not merely limited to temperature and time items, to regulate the synthesis and facilitate the upcoming industrial applications of carbide-based advanced functional materials.

5.
J Mol Cell Cardiol ; 195: 55-67, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39089571

RESUMO

Acute lung injury (ALI) including acute respiratory distress syndrome (ARDS) is a major complication and increase the mortality of patients with cardiac surgery. We previously found that the protein cargoes enriched in circulating extracellular vesicles (EVs) are closely associated with cardiopulmonary disease. We aimed to evaluate the implication of EVs on cardiac surgery-associated ALI/ARDS. The correlations between "oncoprotein-induced transcript 3 protein (OIT3) positive" circulating EVs and postoperative ARDS were assessed. The effects of OIT3-overexpressed EVs on the cardiopulmonary bypass (CPB) -induced ALI in vivo and inflammation of human bronchial epithelial cells (BEAS-2B) were detected. OIT3 enriched in circulating EVs is reduced after cardiac surgery with CPB, especially with postoperative ARDS. The "OIT3 positive" EVs negatively correlate with lung edema, hypoxemia and CPB time. The OIT3-overexpressed EVs can be absorbed by pulmonary epithelial cells and OIT3 transferred by EVs triggered K48- and K63-linked polyubiquitination to inactivate NOD-like receptor protein 3 (NLRP3) inflammasome, and restrains pro-inflammatory cytokines releasing and immune cells infiltration in lung tissues, contributing to the alleviation of CPB-induced ALI. Overexpression of OIT3 in human bronchial epithelial cells have similar results. OIT3 promotes the E3 ligase Cbl proto-oncogene B associated with NLRP3 to induce the ubiquitination of NLRP3. Immunofluorescence tests reveal that OIT3 is reduced in the generation from the liver sinusoids endothelial cells (LSECs) and secretion in liver-derived EVs after CPB. In conclusion, OIT3 enriched in EVs is a promising biomarker of postoperative ARDS and a therapeutic target for ALI after cardiac surgery.


Assuntos
Lesão Pulmonar Aguda , Vesículas Extracelulares , Proteína 3 que Contém Domínio de Pirina da Família NLR , Ubiquitinação , Lesão Pulmonar Aguda/metabolismo , Lesão Pulmonar Aguda/etiologia , Lesão Pulmonar Aguda/patologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Vesículas Extracelulares/metabolismo , Humanos , Animais , Masculino , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Camundongos , Inflamassomos/metabolismo , Proto-Oncogene Mas , Ponte Cardiopulmonar/efeitos adversos , Células Epiteliais/metabolismo , Síndrome do Desconforto Respiratório/metabolismo , Síndrome do Desconforto Respiratório/etiologia , Pulmão/metabolismo , Pulmão/patologia , Peptídeos e Proteínas de Sinalização Intracelular
6.
Clin Gastroenterol Hepatol ; 22(2): 305-314, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-37659766

RESUMO

BACKGROUND & AIMS: Hepatocellular carcinoma (HCC) has a higher incidence in males, but the association of sex with survival remains controversial. This study aimed to examine the effect of sex on HCC survival and its association with age. METHODS: Among 33,238 patients with HCC from 12 Chinese tertiary hospitals, 4175 patients who underwent curative-intent hepatectomy or ablation were analyzed. Cancer-specific survival (CSS) was analyzed using Cox regression and Kaplan-Meier methods. Two propensity score methods and multiple mediation analysis were applied to mitigate confounding. To explore the effect of estrogen, a candidate sex-specific factor that changes with age, female participants' history of estrogen use, and survival were analyzed. RESULTS: There were 3321 males and 854 females included. A sex-related disparity of CSS was present and showed a typical age-dependent pattern: a female survival advantage over males appeared at the perimenopausal age of 45 to 54 years (hazard risk [HR], 0.77; 5-year CSS, 85.7% vs 70.6%; P = .018), peaked at the early postmenopausal age of 55 to 59 years (HR, 0.57; 5-year CSS, 89.8% vs 73.5%; P = .015), and was not present in the premenopausal (<45 y) and late postmenopausal groups (≥60 y). Consistent patterns were observed in patients after either ablation or hepatectomy. These results were sustained with propensity score analyses. Confounding or mediation effects accounted for only 19.5% of sex survival disparity. Female estrogen users had significantly longer CSS than nonusers (HR, 0.74; 5-year CSS, 79.6% vs 72.5%; P = .038). CONCLUSIONS: A female survival advantage in HCC depends on age, and this may be associated with age-dependent, sex-specific factors.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Masculino , Humanos , Feminino , Pessoa de Meia-Idade , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Estudos Retrospectivos , Hepatectomia , Estrogênios , Pontuação de Propensão , Recidiva Local de Neoplasia/patologia
7.
Anal Chem ; 96(37): 15066-15073, 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39225442

RESUMO

In this work, by ingeniously integrating catalytic hairpin assembly (CHA), double-end Mg2+-dependent DNAzyme, and hybridization chain reaction (HCR) as a triple cascade signal amplifier, an efficient concatenated CHA-DNAzyme-HCR (CDH) system was constructed to develop an ultrasensitive electrochemical biosensor with a low-background signal for the detection of microRNA-221 (miRNA-221). In the presence of the target miRNA-221, the CHA cycle was initiated by reacting with hairpins H1 and H2 to form DNAzyme structure H1-H2, which catalyzed the cleavage of the substrate hairpin H0 to release two output DNAs (output 1 and output 2). Subsequently, the double-loop hairpin H fixed on the electrode plate was opened by the output DNAs, to trigger the HCR with the assistance of hairpins Ha and Hb. Finally, methylene blue was intercalated into the long dsDNA polymer of the HCR product, resulting in a significant electrochemical signal. Surprisingly, the double-loop structure of the hairpin H could prominently reduce the background signal for enhancing the signal-to-noise ratio (S/N). As a proof of concept, an ultrasensitive electrochemical biosensor was developed using the CDH system with a detection limit as low as 9.25 aM, achieving favorable application for the detection of miRNA-221 in various cancer cell lysates. Benefiting from its enzyme-free, label-free, low-background, and highly sensitive characteristics, the CDH system showed widespread application potential for analyzing trace amounts of biomarkers in various clinical research studies.


Assuntos
Técnicas Biossensoriais , DNA Catalítico , Técnicas Eletroquímicas , MicroRNAs , MicroRNAs/análise , Técnicas Biossensoriais/métodos , Humanos , DNA Catalítico/química , DNA Catalítico/metabolismo , Hibridização de Ácido Nucleico , Limite de Detecção , Técnicas de Amplificação de Ácido Nucleico
8.
Biochem Biophys Res Commun ; 735: 150745, 2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39395370

RESUMO

Diabetic retinopathy (DR) is the leading cause of blindness and visual loss in people with diabetes. It has been suggested that the progression of DR is associated with chronic inflammation and oxidative stress. The aim of the present work was to evaluate the ability of the natural compound madecassic acid (MEA) to reverse the negative impact of streptozotocin (STZ) on retinal injury in rats. Diabetic rats induced by STZ were treated with MEA at the doses of 10 and 20 mg/kg bw for 8 weeks. The study compared the efficacy of the drug in controlling high blood sugar levels and its impact on therapeutic targets such as SOD, CAT, GPx, NF-κB, TNF-α, IL-6, IL-1ß, VEGF, IGF, bFGF and Keap1/Nrf-2 pathway. The results showed that the treatment with MEA significantly restored the retinal SOD, CAT, and GPx levels in diabetic rats to the near-normal levels. Moreover, the level of inflammatory mediators (TNF-α, IL-1ß, IL-6) and growth factors (VEGF, IGF, bFGF) was significantly lower in retinas of animals treated with MEA as compared to retinas of diabetic animals. The study also established that MEA administration reduced the NF-κB protein and altered the Nrf-2/Keap1 pathway thereby reducing oxidative stress and inflammation. Furthermore, the use of MEA prevented the progression of the retinal capillary basement membrane thickening. It has been found that MEA offers significant protection to the retina and therefore, the compound may be useful in the treatment of DR in humans.

9.
Bioorg Med Chem Lett ; 109: 129822, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38823728

RESUMO

The quest for novel antibacterial agents is imperative in the face of escalating antibiotic resistance. Naturally occurring tetrahydro-ß-carboline (THßC) alkaloids have been highlighted due to their significant biological derivatives. However, these structures have been little explored for antibacterial drugs development. In this study, a series of 1,2,3,4-THßC derivatives were synthesized and assessed for their antibacterial prowess against both gram-positive and gram-negative bacteria. The compounds exhibited moderate to good antibacterial activity, with some compounds showing superior efficacy against gram-positive bacteria, especially methicillin-resistant Staphylococcus aureus (MRSA), to that of Gentamicin. Among these analogs, compound 3k emerged as a hit compound, demonstrating rapid bactericidal action and a significant post-antibacterial effect, with significant cytotoxicity towards human LO2 and HepG2 cells. In addition, compound 3k (10 mg/kg) showed comparable anti-MRSA efficacy to Ciprofloxacin (2 mg/kg) in a mouse model of abdominal infection. Overall, the present findings suggested that THßC derivatives based on the title compounds hold promising applications in the development of antibacterial drugs.


Assuntos
Antibacterianos , Carbolinas , Bactérias Gram-Negativas , Bactérias Gram-Positivas , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Carbolinas/farmacologia , Carbolinas/química , Carbolinas/síntese química , Humanos , Relação Estrutura-Atividade , Animais , Camundongos , Bactérias Gram-Positivas/efeitos dos fármacos , Estrutura Molecular , Bactérias Gram-Negativas/efeitos dos fármacos , Relação Dose-Resposta a Droga , Células Hep G2 , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos
10.
Nanotechnology ; 35(42)2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39047757

RESUMO

To address the global energy shortage and mitigate greenhouse gas emissions on a massive scale, it is critical to explore novel and efficient photocatalysts for the utilization of renewable resources. Bi-based metal oxide (BixMOy) semiconductors composed of bismuth, transition metal, and oxygen atoms have demonstrated improved photocatalytic activity and product selectivity. The vast number of element combinations available for BixMOymaterials provides a huge compositional space for the rational design and isolation of promising photocatalysts for specific applications. In this study, we have systematically investigated the electronic and optical properties over Bi2O3and a series of selected BixMOygroup materials (BiVO4, BiFeO3, BiCoO3, and BiCrO3) by calculating band structure, basic optical property features, mobility and separation of charge carriers. It is clearly noted that the band gap and band edge position of the BixMOygroup materials can be tuned in a wide range in comparison to Bi2O3. Similarly, the light response of BixMOyalso can be broadened from the ultraviolet to the visible light region by adjusting the selection of transition metals. Additionally, the analysis of the effective mass of charge carriers of these materials further confirms their possibility in photocatalytic reaction applications because of the appropriate separation efficiency and mobility of carriers. A selection of experimental investigations on the crystal structure, composition, and optical properties of Bi2O3, BiVO4, and BiFeO3as well as their catalytic performance in the degradation of methylene blue over was also conducted, which agree well with the theoretical predictions.

11.
Acta Pharmacol Sin ; 45(2): 378-390, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37798352

RESUMO

Reinforced cellular responses to endoplasmic reticulum (ER) stress are caused by a variety of pathological conditions including cancers. Human rhomboid family-1 protein (RHBDF1), a multiple transmembrane protein located mainly on the ER, has been shown to promote cancer development, while the binding immunoglobulin protein (BiP) is a key regulator of cellular unfolded protein response (UPR) for the maintenance of ER protein homeostasis. In this study, we investigated the role of RHBDF1 in maintaining ER protein homeostasis in breast cancer cells. We showed that deleting or silencing RHBDF1 in breast cancer cell lines MCF-7 and MDA-MB-231 caused marked aggregation of unfolded proteins in proximity to the ER. We demonstrated that RHBDF1 directly interacted with BiP, and this interaction had a stabilizing effect on the BiP protein. Based on the primary structural motifs of RHBDF1 involved in BiP binding, we found a pentapeptide (PE5) targeted BiP and inhibited BiP ATPase activity. SPR assay revealed a binding affinity of PE5 toward BiP (Kd = 57.7 µM). PE5 (50, 100, 200 µM) dose-dependently promoted ER protein aggregation and ER stress-mediated cell apoptosis in MCF-7 and MDA-MB-231 cells. In mouse 4T1 breast cancer xenograft model, injection of PE5 (10 mg/kg, s.c., every 2 days for 2 weeks) significantly inhibited the tumor growth with markedly increased ER stress and apoptosis-related proteins in tumor tissues. Our results suggest that the ability of RHBDF1 to maintain BiP protein stability is critical to ER protein homeostasis in breast cancer cells, and that the pentapeptide PE5 may serve as a scaffold for the development of a new class of anti-BiP inhibitors.


Assuntos
Neoplasias da Mama , Proteínas de Transporte , Humanos , Animais , Camundongos , Feminino , Proteínas de Transporte/metabolismo , Neoplasias da Mama/tratamento farmacológico , Estresse do Retículo Endoplasmático , Apoptose , Resposta a Proteínas não Dobradas , Proteínas Reguladoras de Apoptose/metabolismo , Imunoglobulinas/metabolismo , Proteínas de Membrana/metabolismo
12.
Chem Biodivers ; 21(9): e202401033, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38945823

RESUMO

Four new clerodane diterpenoids, namely tinocapills A-D (1-4), and one known analogue (5) were isolated from the roots of Tinospora capillipes in the present study. The structures of these new compounds, including their absolute configurations, were determined through a combination of detailed spectroscopic analysis and theoretical statistical approaches, including electronic circular dichroism (ECD) analyses and quantum mechanical (QM)-NMR methods. Additionally, the stereostructure of 5 was confirmed via X-ray diffraction analysis. Furthermore, all these isolates were evaluated for their antibacterial and anti-inflammatory activities. Compounds 1, 2 and 5 demonstrated antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA) with MICs ranging from 4-64 µg/mL, and compounds 3 and 4 exhibited potential anti-inflammatory effects by suppressing LPS-induced TNF-α and NO releases in RAW264.7 cells.


Assuntos
Antibacterianos , Anti-Inflamatórios , Diterpenos Clerodânicos , Staphylococcus aureus Resistente à Meticilina , Testes de Sensibilidade Microbiana , Tinospora , Camundongos , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/isolamento & purificação , Diterpenos Clerodânicos/farmacologia , Diterpenos Clerodânicos/química , Diterpenos Clerodânicos/isolamento & purificação , Animais , Células RAW 264.7 , Tinospora/química , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico/biossíntese , Óxido Nítrico/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Lipopolissacarídeos/antagonistas & inibidores , Lipopolissacarídeos/farmacologia , Conformação Molecular , Raízes de Plantas/química , Estrutura Molecular , Anti-Inflamatórios não Esteroides/farmacologia , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/isolamento & purificação
13.
BMC Biol ; 21(1): 33, 2023 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-36793038

RESUMO

BACKGROUND: Pruning that selectively eliminates unnecessary or incorrect neurites is required for proper wiring of the mature nervous system. During Drosophila metamorphosis, dendritic arbourization sensory neurons (ddaCs) and mushroom body (MB) γ neurons can selectively prune their larval dendrites and/or axons in response to the steroid hormone ecdysone. An ecdysone-induced transcriptional cascade plays a key role in initiating neuronal pruning. However, how downstream components of ecdysone signalling are induced remains not entirely understood. RESULTS: Here, we identify that Scm, a component of Polycomb group (PcG) complexes, is required for dendrite pruning of ddaC neurons. We show that two PcG complexes, PRC1 and PRC2, are important for dendrite pruning. Interestingly, depletion of PRC1 strongly enhances ectopic expression of Abdominal B (Abd-B) and Sex combs reduced, whereas loss of PRC2 causes mild upregulation of Ultrabithorax and Abdominal A in ddaC neurons. Among these Hox genes, overexpression of Abd-B causes the most severe pruning defects, suggesting its dominant effect. Knockdown of the core PRC1 component Polyhomeotic (Ph) or Abd-B overexpression selectively downregulates Mical expression, thereby inhibiting ecdysone signalling. Finally, Ph is also required for axon pruning and Abd-B silencing in MB γ neurons, indicating a conserved function of PRC1 in two types of pruning. CONCLUSIONS: This study demonstrates important roles of PcG and Hox genes in regulating ecdysone signalling and neuronal pruning in Drosophila. Moreover, our findings suggest a non-canonical and PRC2-independent role of PRC1 in Hox gene silencing during neuronal pruning.


Assuntos
Proteínas de Drosophila , Drosophila , Proteínas do Grupo Polycomb , Animais , Axônios/metabolismo , Dendritos/metabolismo , Drosophila/genética , Drosophila/metabolismo , Proteínas de Drosophila/metabolismo , Ecdisona/metabolismo , Plasticidade Neuronal , Proteínas do Grupo Polycomb/genética , Proteínas do Grupo Polycomb/metabolismo
14.
J Sports Sci Med ; 23(1): 672-683, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39228785

RESUMO

Technique-specific high-intensity interval training (HIITTS) has been proven to be an effective method to enhance the sport-specific bio-motor abilities of taekwondo athletes. However, studies regarding its effects on comprehensive measures of cardiorespiratory fitness are limited. Furthermore, there is a lack of clarity regarding the extent of individual adaptations to this method compared to HIIT in the form of repeated sprints (HIITRS). This study compared the individual adaptations to HIITRS and HIITTS on cardiorespiratory fitness and anaerobic power in trained taekwondo athletes (age = 19.8 ± 1.3 years; body mass = 75.4 ± 9.1 kg; height = 1.73 ± 0.0 .m). All participants completed three sessions per week of a 60-minute regular taekwondo training. Following the 60-minute training, participants completed 3 sets of 10 × 4 s all-out HIITRS or same sets of repeated kicks with both legs (HIITTS) over a 6-week training period. In both groups, rest intervals were set at 15 seconds between efforts and one minute between sets. Before and after the training period, participants underwent a series of lab- and field-based tests to evaluate cardiorespiratory fitness and bio-motor abilities. Both interventions resulted in significant improvements in maximum oxygen uptake (V̇O2max), O2 pulse (V̇O2/HR), first ventilatory threshold (VT1), second ventilatory threshold (VT2), cardiac output (Q̇max), stroke volume (SV), peak power output (PPO), average power output (APO), squat jump (SJ), and countermovement jump (CMJ). However, linear speed (20-m speed time) and taekwondo-specific agility test (TSAT) only responded to HIITRS. HIITRS resulted in greater changes in V̇O2max, V̇O2/HR, VT2, and Q̇max, and higher percentage of responders in measured parameters than HIITTS. In addition, HIITRS elicited lower inter-individual variability (CV) in percent changes from pre- to post-training in all measured variables. These results suggest that incorporating 3 sessions per week of HIITRS into regular taekwondo training results in significantly greater and more homogenized adaptations in cardiorespiratory fitness and bio-motor abilities than HIITTS among trained taekwondo athletes.


Assuntos
Aptidão Cardiorrespiratória , Treinamento Intervalado de Alta Intensidade , Artes Marciais , Consumo de Oxigênio , Humanos , Aptidão Cardiorrespiratória/fisiologia , Treinamento Intervalado de Alta Intensidade/métodos , Adulto Jovem , Artes Marciais/fisiologia , Masculino , Frequência Cardíaca/fisiologia , Adaptação Fisiológica , Feminino , Limiar Anaeróbio/fisiologia , Desempenho Atlético/fisiologia
15.
Small ; 19(8): e2206167, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36504426

RESUMO

Broadband infrared (IR) absorption is sought after for wide range of applications. Graphene can support IR plasmonic waves tightly bound to its surface, leading to an intensified near-field. However, the excitation of graphene plasmonic waves usually relies on resonances. Thus, it is still difficult to directly obtain both high near-field intensity and high absorption rate in ultra-broad IR band. Herein, a novel method is proposed to directly realize high near-field intensity in broadband IR band by graphene coated manganous oxide microwires featured hierarchical nanostructures (HNSs-MnO@Gr MWs) both experimentally and theoretically. Both near-field intensity and IR absorption of HNSs-MnO@Gr MWs are enhanced by at least one order of magnitude compared to microwires with smooth surfaces. The results demonstrate that the HNSs-MnO@Gr MWs support vibrational sensing of small organic molecules, covering the whole fingerprint region and function group region. Compared with the graphene-flake-based enhancers, the signal enhancement factors reach a record high of 103 . Furthermore, just a single HNSs-MnO@Gr MW can be constructed to realize sensitively photoresponse with high responsivity (over 3000 V W-1 ) from near-IR to mid-IR. The graphene coated dielectric hierarchical micro/nanoplatform with enhanced near-field intensity is scalable and can harness for potential applications including spectroscopy, optoelectronics, and sensing.

16.
J Synchrotron Radiat ; 30(Pt 2): 308-318, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36891844

RESUMO

Double-crystal monochromators (DCMs) are one of the most critical optical devices in beamlines at synchrotron sources, directly affecting the quality of the beam energy and position. As the performance of synchrotron light sources continues to improve, higher demands are placed on the stability of DCMs. This paper proposes a novel adaptive vibration control method combining variational modal decomposition (VMD) and filter-x normalized least mean squares (FxNLMS), ensuring DCM stability under random engineering disturbance. Firstly, the sample entropy of the vibration signal is selected as the fitness function, and the number of modal components k and the penalty factor α are optimized by a genetic algorithm. Subsequently, the vibration signal is decomposed into band frequencies that do not overlap with each other. Eventually, each band signal is individually governed by the FxNLMS controller. Numerical results have demonstrated that the proposed adaptive vibration control method has high convergence accuracy and excellent vibration suppression performance. Furthermore, the effectiveness of the vibration control method has been verified with actual measured vibration signals of the DCM.

17.
Pharmacol Res ; 198: 106995, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37979663

RESUMO

Melanoma is a dangerous form of skin cancer, making it important to investigate new mechanisms and approaches to enhance the effectiveness of treatment. Here, we establish a positive correlation between the human rhomboid family-1 (RHBDF1) protein and melanoma malignancy. We demonstrate that the melanoma RHBDF1 decrease dramatically inhibits tumor growth and the development of lung metastases, which may be related to the impaired glycolysis. We show that RHBDF1 function is essential to the maintenance of high levels of glycolytic enzymes, especially glucose-6-phosphate isomerase (GPI). Additionally, we discover that the E3 ubiquitin ligase tripartite motif-containing 32 (TRIM32) mediates the K27/K63-linked ubiquitination of GPI and the ensuing lysosomal degradation process. We prove that the multi-transmembrane domain of RHBDF1 is in competition with GPI, preventing the latter from interacting with NCL1-HT2A-LIN41 (NHL) domain of TRIM32. We also note that the mouse RHBDF1's R747 and Y799 are crucial for competitive binding and GPI protection. Artificially silencing the Rhbdf1 gene in a mouse melanoma model results in declined lactic acid levels, elevated cytotoxic lymphocyte infiltration, and improved tumor responsiveness to immunotherapy. These results provide credence to the hypothesis that RHBDF1 plays a significant role in melanoma regulation and suggest that blocking RHBDF1 may be an efficient technique for reestablishing the tumor immune microenvironment (TIME) in melanoma and halting its progression.


Assuntos
Glucose-6-Fosfato Isomerase , Melanoma , Humanos , Animais , Camundongos , Glucose-6-Fosfato Isomerase/genética , Glucose-6-Fosfato Isomerase/metabolismo , Proteínas de Membrana/metabolismo , Ubiquitinação , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Melanoma/genética , Melanoma/terapia , Imunoterapia , Microambiente Tumoral , Proteínas com Motivo Tripartido/genética , Proteínas com Motivo Tripartido/metabolismo , Fatores de Transcrição/metabolismo
18.
Eur Radiol ; 33(11): 7942-7951, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37294329

RESUMO

OBJECTIVES: To assess the safety and efficacy of ultrasound-guided thermal ablation for low-risk papillary thyroid microcarcinoma (PTMC) via a prospective multicenter study. METHODS: From January 2017 through June 2021, low-risk PTMC patients were screened. The management details of active surveillance (AS), surgery, and thermal ablation were discussed. Among patients who accepted thermal ablation, microwave ablation (MWA) was performed. The main outcome was disease-free survival (DFS). The secondary outcomes were tumor size and volume changes, local tumor progression (LTP), lymph node metastasis (LNM), and complication rate. RESULTS: A total of 1278 patients were included in the study. The operation time of ablation was 30.21 ± 5.14 min with local anesthesia. The mean follow-up time was 34.57 ± 28.98 months. Six patients exhibited LTP at 36 months, of whom 5 patients underwent a second ablation, and 1 patient received surgery. The central LNM rate was 0.39% at 6 months, 0.63% at 12 months, and 0.78% at 36 months. Of the 10 patients with central LNM at 36 months, 5 patients chose ablation, 3 patients chose surgery and the other 2 patients chose AS. The overall complication rate was 1.41%, and 1.10% of patients developed hoarseness of the voice. All of the patients recovered within 6 months. CONCLUSIONS: Thermal ablation of low-risk PTMC was observed to be safe and efficacious with few minor complications. This technique may help to bridge the gap between surgery and AS as treatment options for patients wishing to have their PTMC managed in a minimally invasive manner. CLINICAL RELEVANCE STATEMENT: This study proved that microwave ablation is a safe and effective treatment method for papillary thyroid microcarcinoma. KEY POINTS: Percutaneous US-guided microwave ablation of papillary thyroid microcarcinoma is a very minimally invasive treatment under local anesthesia during a short time period. The local tumor progression and complication rate of microwave ablation in the treatment of papillary thyroid microcarcinoma are very low.


Assuntos
Ablação por Radiofrequência , Neoplasias da Glândula Tireoide , Humanos , Micro-Ondas/uso terapêutico , Estudos Prospectivos , Neoplasias da Glândula Tireoide/cirurgia , Neoplasias da Glândula Tireoide/patologia , Ablação por Radiofrequência/métodos , Resultado do Tratamento , Estudos Retrospectivos
19.
Int J Hyperthermia ; 40(1): 2249274, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37751897

RESUMO

OBJECTIVE: To investigate the factors affecting the efficacy of ultrasound (US)-guided percutaneous microwave ablation (PMWA) for adenomyosis with abnormal uterine bleeding (AUB-A). METHODS: Baseline data of patients with AUB-A who underwent US-guided PMWA treatment between October 2020 and October 2021, including demography characteristics, laboratory and imaging examination results were retrospectively analyzed. 3D reconstruction of magnetic resonance imaging (MRI) was applied to quantitatively assess the local treatment responses, including ratio of non-perfusion volume to adenomyosis volume (NPVr), ablation rate of the endometrial-myometrial junction (EMJ), and surface area (SA) of the ablated part of the EMJ. Patients were followed up at 3, 6, and 12 months after treatment, and divided into two groups: group with complete relief (CR), and group with partial relief (PR) or no relief (NR). Data were compared between them. RESULTS: Thirty-one patients were analyzed with a mean age of 38.7 ± 6.8 years (range: 24-48): 48.4% (15/31), 63.3% (19/30), and 65.5% (19/29) achieved CR at 3, 6, and 12 months, respectively. In univariate analysis, compared with the PR/NR group, serum CA125 levels were significantly lower in CR group at 3 months, while ablation rates of EMJ and SA of the ablated part of the EMJ were significantly higher at the three time points. Other baseline characteristics and NPVr did not differ between the two groups. CONCLUSION: Baseline CA125 and ablation rate of the EMJ and SA of the ablated part of the EMJ are associated with the outcome of AUB-A patients after US-guided PMWA treatment.


Assuntos
Adenomiose , Humanos , Feminino , Adulto , Pessoa de Meia-Idade , Adenomiose/complicações , Adenomiose/diagnóstico por imagem , Adenomiose/cirurgia , Micro-Ondas/uso terapêutico , Estudos Retrospectivos , Ultrassonografia de Intervenção , Hemorragia Uterina
20.
Nucleic Acids Res ; 49(5): 2522-2536, 2021 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-33561291

RESUMO

Simultaneous dysregulation of multiple microRNAs (miRs) affects various pathological pathways related to cardiac failure. In addition to being potential cardiac disease-specific markers, miR-23b/27b/24-1 were reported to be responsible for conferring cardiac pathophysiological processes. In this study, we identified a conserved guanine-rich RNA motif within the miR-23b/27b/24-1 cluster that can form an RNA G-quadruplex (rG4) in vitro and in cells. Disruption of this intragenic rG4 significantly increased the production of all three miRs. Conversely, a G4-binding ligand tetrandrine (TET) stabilized the rG4 and suppressed miRs production in human and rodent cardiomyocytes. Our further study showed that the rG4 prevented Drosha-DGCR8 binding and processing of the pri-miR, suppressing the biogenesis of all three miRs. Moreover, CRISPR/Cas9-mediated G4 deletion in the rat genome aberrantly elevated all three miRs in the heart in vivo, leading to cardiac contractile dysfunction. Importantly, loss of the G4 resulted in reduced targets for the aforementioned miRs critical for normal heart function and defects in the L-type Ca2+ channel-ryanodine receptor (LCC-RyR) coupling in cardiomyocytes. Our results reveal a novel mechanism for G4-dependent regulation of miR biogenesis, which is essential for maintaining normal heart function.


Assuntos
Quadruplex G , MicroRNAs/química , MicroRNAs/metabolismo , Contração Miocárdica/genética , Miócitos Cardíacos/metabolismo , Animais , Benzilisoquinolinas/farmacologia , Sistemas CRISPR-Cas , Células Cultivadas , Quadruplex G/efeitos dos fármacos , Regulação da Expressão Gênica , Miocárdio/metabolismo , Miócitos Cardíacos/fisiologia , Processamento Pós-Transcricional do RNA , Proteínas de Ligação a RNA/metabolismo , Ratos , Ratos Sprague-Dawley , Ribonuclease III/metabolismo , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo
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