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1.
Rev. esp. enferm. dig ; 115(9): 496-503, sep. 2023. ilus, tab, graf
Artigo em Inglês | IBECS | ID: ibc-225136

RESUMO

Background and aim: endoscopic anti-reflux mucosectomy (ARMS) is effective for patients with refractory gastroesophageal reflux disease (rGERD) with small hiatus hernia. However, evidence of its applicability in patients with larger hernia sac is lacking. This study aimed to evaluate the efficiency and safety of ARMS for patients with rGERD with moderate hiatus hernia (3-5 cm) and determine the appropriate resection range. Methods: thirty-six patients with rGERD with moderate hiatus hernia were enrolled. They were divided into 2/3 and 3/4 circumferential mucosal resection groups. The patients received modified ARMS. The gastroesophageal reflux disease questionnaire (GERD-Q) and DeMeester scores, endoscopy, 24-h pH monitoring results and lower esophageal sphincter (LES) resting pressure were compared pre- and post-procedure. Therapeutic effects and complications of the two mucosal resection ranges were analyzed. Results: thirty-six patients were enrolled in this study, all of whom had undergone ARMS surgery with at least six-month follow-up. In the 2/3 circumferential mucosal resection group, the GERD-Q score, acid exposure time (AET) and DeMeester score improved significantly compared with those before surgery (p < 0.001). In the 3/4 circumferential mucosal resection group, the GERD-Q score, AET and DeMeeter score worsened after six months (p < 0.001), but there was no difference between the two groups (p > 0.05). In both groups, there was no significant improvement in the ratio of esophagitis grade C/D and LES resting pressure after treatment compared with the baseline values (p > 0.05), and no postoperative bleeding or perforation was observed. The incidence of postoperative esophageal stenosis in the 2/3 circumferential mucosal resection group was lower than that in the 3/4 circumferential mucosal resection group (p = 0.041). (AU)


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Hérnia Hiatal/tratamento farmacológico , Refluxo Gastroesofágico/tratamento farmacológico , Ressecção Endoscópica de Mucosa/instrumentação , Endoscopia , Estudos Prospectivos , Estudos de Casos e Controles
3.
J Integr Plant Biol ; 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37698072

RESUMO

The lack of genome editing platforms has hampered efforts to study and improve forage crops that can be grown on lands not suited to other crops. Here, we established efficient Agrobacterium-mediated CRISPR/Cas9 genome editing in a perennial, stress-tolerant forage grass, sheepgrass (Leymus chinensis). By screening for active single-guide RNAs (sgRNAs), accessions that regenerate well, suitable Agrobacterium strains, and optimal culture media, and co-expressing the morphogenic factor TaWOX5, we achieved 11% transformation and 5.83% editing efficiency in sheepgrass. Knocking out Teosinte Branched1 (TB1) significantly increased tiller number and biomass. This study opens avenues for studying gene function and breeding in sheepgrass. This article is protected by copyright. All rights reserved.

4.
Front Psychol ; 14: 1142496, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37691792

RESUMO

In recent decades, the practice of involving teachers in research in degree programs is becoming popular. Yet, little is known about the impact of research experiences on teachers' behavior: whether research experiences change their teaching practices and lead to further research efforts in future careers, especially in the unique social, cultural, and educational culture of China. Thus, this study examines Chinese IETs' (in-service EFL teachers') research attitudes in a graduate program with a reasoned action approach. We used an embedded mixed methods research design to investigate a cohort of 197 IETs who completed the Research Attitudes in Vocational Education Questionnaire (RAVE-Q). The quantitative data validates the survey and shows that, in general, the IETs hold positive attitudes toward research. Next, semi-structured interviews investigating IETs and their advisors' perceptions of teacher research were conducted. The qualitative data shows a variety of research experiences among the IETs. Specifically, this study highlighted some interviewed IETs who had the desire to be reflective about their teaching and to apply research in their practices, nevertheless, the educational contexts made such efforts impossible. Thus, this study questioned the previous assumptions that positive research attitudes lead to corresponding research behaviors. This study offers implications for EFL graduate programs seeking to improve IETs' research attitudes both within and outside China.

5.
Math Biosci Eng ; 20(8): 14136-14157, 2023 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-37679129

RESUMO

Drugs, which treat various diseases, are essential for human health. However, developing new drugs is quite laborious, time-consuming, and expensive. Although investments into drug development have greatly increased over the years, the number of drug approvals each year remain quite low. Drug repositioning is deemed an effective means to accelerate the procedures of drug development because it can discover novel effects of existing drugs. Numerous computational methods have been proposed in drug repositioning, some of which were designed as binary classifiers that can predict drug-disease associations (DDAs). The negative sample selection was a common defect of this method. In this study, a novel reliable negative sample selection scheme, named RNSS, is presented, which can screen out reliable pairs of drugs and diseases with low probabilities of being actual DDAs. This scheme considered information from k-neighbors of one drug in a drug network, including their associations to diseases and the drug. Then, a scoring system was set up to evaluate pairs of drugs and diseases. To test the utility of the RNSS, three classic classification algorithms (random forest, bayes network and nearest neighbor algorithm) were employed to build classifiers using negative samples selected by the RNSS. The cross-validation results suggested that such classifiers provided a nearly perfect performance and were significantly superior to those using some traditional and previous negative sample selection schemes.


Assuntos
Algoritmos , Reposicionamento de Medicamentos , Humanos , Teorema de Bayes , Análise por Conglomerados , Algoritmo Florestas Aleatórias
6.
Langmuir ; 39(36): 12817-12825, 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37655503

RESUMO

As an allotrope of phosphorus and a promising 2D semiconductor, black phosphorus (BP) exhibits in-plane anisotropy along its armchair and zigzag crystal directions, allowing for efficient regulation of near-field radiative heat transfer (NFRHT). In this work, we investigate the NFRHT between two multilayer BP/hBN heterostructures and theoretically demonstrate that thermal regulation can be realized by tuning the electron density and rotation angle of BP. Results show that a larger electron density leads to the coupling of anisotropic surface plasmon polaritons (SPPs) of BP with hyperbolic modes of hBN, and rotation of BP changes the anisotropic characteristic of coupled SPPs on both sides, whereby a regulation ratio of 5.8 can be obtained. We also analyze the effects of period number, hBN layer thickness, and topmost-layer material on the NFRHT. This work may be beneficial for efficient nanoscale thermal management and physical understanding of radiative heat transfer based on anisotropic SPPs.

7.
Chin Neurosurg J ; 9(1): 24, 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37691095

RESUMO

BACKGROUND: Coil embolization is a common method for treating unruptured intracranial aneurysms (UIAs). To effectively perform coil embolization for UIAs, clinicians must undergo extensive training with the assistance of senior physicians over an extended period. This study aimed to establish a deep-learning system for measuring the morphological features of UIAs and help the surgical planning of coil embolization for UIAs. METHODS: Preoperative computational tomography angiography (CTA) data and surgical data from UIA patients receiving coil embolization in our medical institution were retrospectively reviewed. A convolutional neural network (CNN) model was trained on the preoperative CTA data, and the morphological features of UIAs were measured automatically using this CNN model. The intraclass correlation coefficient (ICC) was utilized to examine the similarity between the morphologies measured by the CNN model and those determined by experienced clinicians. A deep neural network model to determine the diameter of first coil was further established based on the CNN model within the derivation set (75% of all patients) using neural factorization machines (NFM) model and was validated using a validation set (25% of all patients). The general match ratio (the difference was within ± 1 mm) between the predicted diameter of first coil by model and that used in practical scenario was calculated. RESULTS: One-hundred fifty-three UIA patients were enrolled in this study. The CNN model could diagnose UIAs with an accuracy of 0.97. The performance of this CNN model in measuring the morphological features of UIAs (i.e., size, height, neck diameter, dome diameter, and volume) was comparable to the accuracy of senior clinicians (all ICC > 0.85). The diameter of first coil predicted by the model established based on CNN model and the diameter of first coil used actually exhibited a high general match ratio (0.90) within the derivation set. Moreover, the model performed well in recommending the diameter of first coil within the validation set (general match ratio as 0.91). CONCLUSION: This study presents a deep-learning system which can help to improve surgical planning of coil embolization for UIAs.

8.
Int J Biol Macromol ; : 126852, 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37703970

RESUMO

The purpose of this study was to investigate the effect of Kappa (к)-carrageenan on texture and perception of saltiness of low salt surimi. The low-field nuclear magnetic resonance (LF-NMR) and microstructure results showed that к-carrageenan could promote the formation of more immobilized water in low salt surimi gel, change its matrix structure, and lead to the uneven spatial distribution of sodium, thus enhancing saltiness perception. The rheological properties of surimi showed that к-carrageenan could increase the network strength of low salt surimi gel and improve its thermostability. Furthermore, the low salt surimi gel added with к-carrageenan has lower cooking loss, higher water holding capacity (WHC), gel strength and improved texture properties. Therefore, κ-carrageenan has the effects of improving the quality and increasing salt perception of surimi gel. This study provides a new method for reducing salt consumption in food industry.

9.
Int J Biol Macromol ; : 126895, 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37709233

RESUMO

In the present work, a dual-modified waxy rice starch (OOWRS) fabricated with OSA and ozone was successfully used to stabilize the O/W Pickering emulsion. The molecular structure, surface properties, and underlying stabilizing mechanism were systematically investigated. The results showed that oxidation occurring on the surface of OSA-modified waxy rice starch (OSAWRS) resulted in the presence of indentations and cracks. The relative crystallinity of starch was generally decreased with increasing degree of oxidation. Due to the introduction of carbonyl and the variation in surface structure, the hydrophobicity and acidity of OSAWRS were significantly enhanced after the ozone treatment. Remarkably, OOWRS stabilized Pickering emulsion exhibited a feature of typical O/W emulsion, and the 0.5 h and 1 h OOWRS emulsion exhibited a more uniform droplet size as well as a higher surface potential. We also noted that a weak-gel network was formed within the OOWRS emulsion system as the hydrophilic starch chains played a bridging role. Two reasons for the improved stability of the emulsion were the special gel structure and the enhanced electrical repulsion among the droplets. This research provides that ozone-conjugated OSA modification is a promising strategy for improving the emulsion ability of starch-based Pickering emulsions.

10.
Reprod Domest Anim ; 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37712626

RESUMO

Peroxisome proliferator-activated receptor γ (PPARγ) is highly expressed in trophoblast tissues in pregnancy during which the protein participates in diverse events, including embryo implantation and placental formation. However, little is known about the role of PPARγ in embryonic development. This study investigated the function of PPARγ in sheep trophoblast cells. The coding sequence of sheep PPARγ encoded 475 amino acids and included one synonymou mutation compared with the sheep reference sequence for PPARγ. The PPARγ protein was localized in the nucleus and cytoplasm of sheep trophoblasts. The relative expression of PPARγ was elevated in cells treated with rosiglitazone and reduced following administration of GW9662. Activation of PPARγ promoted cell proliferation and mobility, but inhibited apoptosis. In addition, stimulation of PPARγ promoted the expression of lipid metabolism-related genes FABP4 and PLIN2. The expression of prostaglandin metabolism-related genes PLA2G4A, PTGS2 and PTGES also was upregulated significantly in trophoblast cells when PPARγ was activated. In contrast, activation of PPARγ did not impact expression of the prostaglandin-related genes PGFS and SLCO2A1. At the same time, activation of PPARγ activity increased the ratio of PGE2 to PGF2α. Furthermore, fluorescence labelling showed that the numbers of cell lipid droplets increased after stimulation of PPARγ activity, but decreased when PPARγ was inhibited. In conclusion, PPARγ is critical for the regulation of lipid metabolism and prostaglandin synthesis and secretion in sheep trophoblast cells and also has a potent effect on cell proliferation and viability.

11.
Genes Genomics ; 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37713069

RESUMO

BACKGROUND: Tendon stem/progenitor cells (TSPCs) play a vital role in tendon repair, regeneration and homeostasis. However, the specific mechanism of TSPCs aging is still unclear. OBJECTIVE: This study aims to explore the role and molecular mechanism of HPF1 in the aging of TSPCs. METHODS: Young and aged TSPCs (Y-TSPCs and A-TSPCs) were acquired from 3 to 4 and 24-26-month-old Sprague-Dawley male rats, TSPCs (Y-TSPCs and A-TSPCs) were subjected to senescence-associated ß-galactosidase (SA-ß-Gal))staining and telomerase activity detection, p16, p21, Scx, Tnmd, Col1, Col3HPF1 and PAPR1 expression levels were detected by Western blot or Reverse Transcription-quantitative Polymerase Chain Reaction (RT-qPCR), Reciprocal co-immunoprecipitation (co-IP) was used to explore the interaction between HPF1 and PARP1. Ribonucleoprotein immunoprecipitation (RNP-IP) was used to analyze the binding of HuR to the senescence marker gene mRNAs, IP was used to perform HPF1 to the PARylation of HuR, and the half-life of p16 and p21 were detected. Finally, we established an in vivo model, and the tendon tissue was used to perform hematoxylin and eosin (HE) and masson's trichrome staining, as well as the immunohistochemical analysis of Col I and TNMD. RESULTS: Compared with Y-TSPCs, A-TSPCs had significantly enhanced cell senescence and significantly reduced tendon differentiation ability, and significantly increased the expression of HPF1 and PARP1. In addition, HPF1 and PARP1 interacted and coordinated the senescence and differentiation of TSPCs, HPF1 could also regulate the expression of p21 and p21, the interaction of p16 or p21 with HuR, and the poly-ADP ribosylation of PARP1 to HuR. HPF1 overexpression and siHuR co-transfection significantly reduced the half-life of p16 and p21, and HPF1 and PARP1 regulated the mRNA levels of p16 and p21 through HuR. Finally, in vivo experiments have shown that HPF1 or PARP1 overexpression could both inhibit the ability of tendon differentiation and promote cell senescence. CONCLUSIONS: HPF1 promoted the senescence of TSPCs and inhibits the tendon differentiation of TSPCs through PARP1-mediated poly-ADP ribosylation of HuR.

12.
Biosens Bioelectron ; 240: 115637, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37669587

RESUMO

At present, the 100% case fatality and the cross-infection of virus strains make the ASFV 's harm to society continue to expand. The absence of an effective commercial vaccine poses early detection remains the most effective means of curbing ASFV infection. Here, we report a cascaded detection platform based on the CRISPR-Cas12a system combined with graphene field-effect transistor sensors. The cascade platform could detect ASFV as low as 0.5 aM within 30 min and achieve typing of wild and vaccine strains of ASFV in a single detection system. The evaluation of 16 clinical samples proved that, compared with the gold standard Real-time PCR method, this platform has outstanding advantages in sensitivity, specificity and typing. Combining CRISPR-Cas12a's high specificity with the bipolar electric field effect of graphene field-effect transistor, the cascade platform is expected to achieve clinical application in the field of DNA disease detection, and provides a new direction for multi-strain disease typing.


Assuntos
Técnicas Biossensoriais , Grafite , Sistemas CRISPR-Cas/genética , Eletricidade , Reação em Cadeia da Polimerase em Tempo Real
13.
Int J Pharm ; 645: 123412, 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37703956

RESUMO

Viral pneumonia (VP) is a serious health risk to humans, however, there is still a lack of specific treatments for VP. The spread of the virus in the body induces an excessive inflammatory response that can cause chronic or irreversible damage to lungs. Hence, VP treatment requires rapid clearance of the virus and sustained inflammation control. In this study, an innovative mesoporous silica medication delivery system co-loaded with Ziyuglycoside I(ZgI) and Oseltamivirv(OST) in fast and slow monomeric forms ZgI@MSNs-OST@ Polydopamine (PDA) was prepared for targeted treatment of VP. The prepared ZgI@MSNs-OST@PDA nanoparticles had a homogeneous and membrane-encapsulated spherical structure, with an average particle size of approximately 760 nm. in vitro release and in vivo pharmacokinetic studies demonstrated that ZgI@MSNs-OST@PDA achieved immediate release of OST and sustained release of ZgI, which was readily taken up by the cells. In vitro anti-H1N1 virus experiments showed that nanoparticles rapidly killed the virus in host cells, and the anti-inflammatory effect was sustained and long-lasting, providing excellent protection to host cells. In vivo antiviral pneumonia experiments confirmed the rapid clearance of influenza viruses from mouse lungs and the effective control of overactivated immune responses by ZgI@MSNs-OST@PDA nanoparticles. Through a mechanistic study, we found that the treatment of viral pneumonia with nanoparticles was associated with inhibition of the NLRP3 inflammasome pathway. In conclusion, the constructed nanoparticles achieved synergistic therapeutic effects of ZgI and OST on VP, that is, rapid killing of influenza viruses by OST and effective control of the virus-induced hyperinflammatory response by ZgI.

14.
J Comput Assist Tomogr ; 47(5): 766-773, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37707407

RESUMO

OBJECTIVE: We aimed to develop and validate a computed tomography (CT)-based radiomics model for early relapse prediction in patients with Ewing sarcoma (ES). METHODS: We recruited 104 patients in this study. Tumor areas and areas with a tumor expansion of 3 mm were used as regions of interest for radiomics analysis. Six different models were constructed: Pre-CT, CT enhancement (CTE), Pre-CT +3 mm , CTE +3 mm , Pre-CT and CTE combined (ComB), and Pre-CT +3 mm and CTE +3 mm combined (ComB +3 mm ). All 3 classifiers used a grid search with 5-fold cross-validation to identify their optimal parameters, followed by repeat 5-fold cross-validation to evaluate the model performance based on these parameters. The average performance of the 5-fold cross-validation and the best one-fold performance of each model were evaluated. The AUC (area under the receiver operating characteristic curve) and accuracy were calculated to evaluate the models. RESULTS: The 6 radiomics models performed well in predicting relapse in patients with ES using the 3 classifiers; the ComB and ComB +3 mm models performed better than the other models (AUC -best : 0.820-0.922/0.823-0.833 and 0.799-0.873/0.759-0.880 in the training and validation cohorts, respectively). Although the Pre-CT +3 mm , CTE +3 mm, and ComB +3 mm models covering tumor per se and peritumoral CT features preoperatively forecasted ES relapse, the model was not significantly improved. CONCLUSIONS: The radiomics model performed well for early recurrence prediction in patients with ES, and the ComB and ComB +3 mm models may be superior to the other models.

15.
Nanoscale ; 2023 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-37721019

RESUMO

Na2Ti3O7 (NTO) is recognized as an authenticated promising photocatalyst and surface-enhanced Raman scattering (SERS) active material, although its performance is limited by its high carrier recombination rate, wide band gap and inadequate utilization of visible light. In this study, to solve these issues, sea urchin-shaped NTO nanowires directly grown on a substrate were fabricated, and then Ag nanoparticles were decorated on NTO nanowires using sputtering equipment. The as-prepared Ag-NTO substrates exhibited different morphologies and high SERS activity, which was confirmed by finite-difference time-domain (FDTD) simulations, showing that appropriate Ag decoration can bring more nanogaps and thus enhance the electromagnetic field (EM) contribution. We visualized the charge transfer (CT) mechanism in SERS and further investigated the catalytic hydrogen production process similarly induced by photogenerated CT. The optimal SERS substrate (Ag-NTO-3) was adopted to verify the photocatalytic hydrogen evolution (PHE) activity, and the hydrogen evolution rate of Ag-NTO-3 was 106.7 µmol h-1 (twice that of pristine NTO). Photoelectrochemical measurements and photoluminescence (PL) analysis were used to elucidate the potential enhancement mechanisms for the photocatalytic performance and CT process. This study can provide a valuable reference for performance and mechanism studies of SERS substrates and photocatalysts.

16.
Anal Chim Acta ; 1278: 341757, 2023 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-37709482

RESUMO

At present, methicillin-resistant Staphylococcus aureus (MRSA) has caused a serious impact on a global scale. The infection and carrier rate of MRSA in the community is increasing year by year, but there is still no convenient detection system for on-site rapid detection. It is very important to select a rapid detection system to accurately and quickly detect patients infected with MRSA. We have developed a high-efficient single-tube detection platform based on RPA and CRISPR reaction system to detect the genes of mecA and clfA of MRSA. Using this detection platform, visual MRSA detection could be achieved in 30 min. It was observed that this detection platform was capable to successfully detect the target genomic as low as 5 copies µL-1, and the reaction was completed in one step without opening the lid. This detection platform could only detect MRSA, but not other common clinical pathogenic bacteria, such as Salmonella, Pseudomonas aeruginosa, Staphylococcus xylosus, Aeromonas hydrophila, Escherichia coli and Staphylococcus warneri, indicated its satisfactory selectivity for MRSA without interference from other bacteria. The results of clinical samples show that the platform has outstanding advantages in sensitivity, specificity and identification of methicillin resistance. The entire reaction can be completed in one step in the handheld instrument without opening the cover, avoiding aerosol pollution during the reaction. The detection platform combined with handheld instruments will have great application potential in point-of-care testing.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Humanos , Staphylococcus aureus Resistente à Meticilina/genética , Sistemas CRISPR-Cas , Poluição Ambiental , Escherichia coli , Testes Imediatos
17.
Plants (Basel) ; 12(17)2023 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-37687312

RESUMO

The subtilisin-like protease (SBT) family is widely known for its role in stress resistance to a number of stressors in different plant species, but is rarely studied in wheat. Subtilisin-like serine proteases (SBTs) are serine proteolytic enzymes that hydrolyze proteins into small peptides, which bind to receptors as signal molecules or ligands and participate in signal transduction. In this study, we identified 255 putative SBT genes from the wheat reference genome and then divided these into seven clades. Subsequently, we performed syntenic relation analysis, exon-intron organization, motif composition, and cis-element analysis. Further, expression analysis based on RNA-seq and tissue-specific expression patterns revealed that TaSBT gene family expression has multiple intrinsic functions during various abiotic and biotic stresses. Analysis of RNA-seq expression assays and further validation through qRT PCR suggested that some of the TaSBT genes have significant changes in expression levels during Pst interaction. TaSBT7, TaSBT26, TaSBT102, and TaSBT193 genes showed increasing expression levels during compatible and non-compatible interactions, while the expression levels of TaSBT111 and TaSBT213 showed a decreasing trend, indicating that these members of the wheat SBT gene family may have a role in wheat's defense against pathogens. In conclusion, these results expand our understanding of the SBT gene family, and provide a valuable reference for future research on the stress resistance function and comprehensive data of wheat SBT members.

18.
Sensors (Basel) ; 23(17)2023 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-37688070

RESUMO

Knowledge distillation (KD) is a well-established technique for compressing neural networks and has gained increasing attention in object detection tasks. However, typical object detection distillation methods use fixed-level semantic features for distillation, which might not be best for all training stages and samples. In this paper, a multilayer semantic feature adaptive distillation (MSFAD) method is proposed that uses a routing network composed of a teacher and a student detector, along with an agent network for decision making. Specifically, the inputs to the proxy network consist of the features output by the neck structures of the teacher and student detectors, and the output is a decision on which features to choose for distillation. The MSFAD method improves the distillation training process by enabling the student detector to automatically select valuable semantic-level features from the teacher detector. Experimental results demonstrated that the proposed method increased the mAP50 of YOLOv5s by 3.4% and the mAP50-90 by 3.3%. Additionally, YOLOv5n with only 1.9 M parameters achieved detection performance comparable to that of YOLOv5s.

19.
Neuropharmacology ; 240: 109710, 2023 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-37683885

RESUMO

Pyramidal neuron (Pyn) hyperactivity in the anterior cingulate cortex (ACC) is involved in the modulation of pain. Previous studies indicate that the activation of α2 adrenoceptors (α2-ARs) by dexmedetomidine (DEX) is a safe and effective means of alleviating multiple types of pain. Here, we showed that systemically administered DEX can ameliorate the inflammatory pain induced by hindpaw injection of formalin (FA) and further examined the molecular and synaptic mechanisms of this DEX-elicited antinociceptive effect. We found that FA caused an increase in c-Fos expression in contralateral layer 2/3 (L2/3) ACC, and that intra-ACC infusion of DEX could also relieve phase 2 inflammatory pain behavior. DEX elicited an increase in the amplitude and frequency of miniature inhibitory post-synaptic currents (mIPSCs) and evoked IPSC amplitude, as well as a reduction in the hyperexcitability and both paired-pulse and excitation/inhibition ratios in contralateral L2/3 ACC Pyns of FA mice. These electrophysiological effects were associated with the upregulation of GABA A receptor (GABAAR) subunits. The interaction of phosphorylated Akt (p-Akt) with GABAAR subunits increased in the ACC following administration of DEX. These results suggest that DEX treatment reduces hyperactivity and enhances GABAergic inhibitory synaptic transmission in ACC Pyns, which produces analgesic effects by increasing GABAAR levels and activating the Akt signaling pathway.

20.
Langmuir ; 39(37): 13222-13227, 2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37658471

RESUMO

Friction-induced surface amorphization of silicon is one of the most important surface wear and damage forms, changing the material properties and harming the reliability of silicon-based devices. However, knowledge regarding the amorphization mechanisms as well as the effects of temperature is still insufficient, because the experimental measurements of the crystal-amorphous interface structures and evolutions are extremely difficult. In this work, we aim to fully reveal the temperature dependence of silicon amorphization behaviors and relevant mechanisms by using reactive molecular dynamics simulations. We first show that the degree of amorphization is suppressed by the increasing temperature, contrary to our initial expectations. Then, we further revealed that the observed silicon amorphization behaviors are attributed to two independent processes: One is a thermoactivated and shear-driven amorphization process where the theoretical amorphization rate shows an interesting valley-like temperature dependence because of the competition between the increased thermal activation effect and the reduction of shear stress, and another one is a thermoactivated recrystallization process which shows a monotonically increasing trend with temperature. Thus, the observed reduction of amorphization with temperature is mainly due to the recrystallization effect. Additionally, analytical models are proposed in this work to describe both the amorphization and the recrystallization processes. Overall, the present findings provide deep insights into the temperature-dependent amorphization and recrystallization processes of silicon, benefiting the further development of silicon-based devices and technologies.

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