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1.
Sci Rep ; 14(1): 23346, 2024 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-39375492

RESUMO

This study introduces a novel graphene RF NEMS capacitive switch and conducts an extensive analysis of its RF performance using CST and COMSOL Multiphysics software. The switch's characteristic impedance matching is accomplished through a coplanar waveguide (CPW) structure, incorporating a dielectric layer topped with conductive graphene beam electrodes. Simulation results reveal that the monolayer graphene RF NEMS switch maintains an insertion loss of 0.003 ~ 0.015 dB and an isolation greater than 40 dB across an ultra-wideband (UWB) frequency range of DC ~ 140 GHz. Moreover, the switch demonstrates a switching time of 4.03 ps at a pull-in voltage of 1 V. The performance of multilayer graphene RF NEMS switches was also evaluated. The study further investigates the operational mechanism of the graphene RF NEMS switch and performs finite element analysis on the proposed design. The graphene RF NEMS switch discussed herein offers significant advantages, including minimal size, lightweight, cost-effectiveness, low pull-in voltage, rapid response time, excellent RF performance, and reduced space consumption in circuitry. Its potential applications span a range from L to F bands, encompassing data storage, communication systems, sensors, remote sensing and military uses.

2.
Phys Med Biol ; 69(2)2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-38086073

RESUMO

Objective.PET (Positron Emission Tomography) inherently involves radiotracer injections and long scanning time, which raises concerns about the risk of radiation exposure and patient comfort. Reductions in radiotracer dosage and acquisition time can lower the potential risk and improve patient comfort, respectively, but both will also reduce photon counts and hence degrade the image quality. Therefore, it is of interest to improve the quality of low-dose PET images.Approach.A supervised multi-modality deep learning model, named M3S-Net, was proposed to generate standard-dose PET images (60 s per bed position) from low-dose ones (10 s per bed position) and the corresponding CT images. Specifically, we designed a multi-branch convolutional neural network with multi-self-attention mechanisms, which first extracted features from PET and CT images in two separate branches and then fused the features to generate the final generated PET images. Moreover, a novel multi-modality structure-promoting term was proposed in the loss function to learn the anatomical information contained in CT images.Main results.We conducted extensive numerical experiments on real clinical data collected from local hospitals. Compared with state-of-the-art methods, the proposed M3S-Net not only achieved higher objective metrics and better generated tumors, but also performed better in preserving edges and suppressing noise and artifacts.Significance.The experimental results of quantitative metrics and qualitative displays demonstrate that the proposed M3S-Net can generate high-quality PET images from low-dose ones, which are competable to standard-dose PET images. This is valuable in reducing PET acquisition time and has potential applications in dynamic PET imaging.


Assuntos
Neoplasias , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Humanos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Processamento de Imagem Assistida por Computador/métodos , Tomografia por Emissão de Pósitrons/métodos , Redes Neurais de Computação
3.
Antioxidants (Basel) ; 12(9)2023 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-37760076

RESUMO

This study aimed to investigate the effects of dietary tannic acid (TAN) on the gas production, growth performance, antioxidant capacity, rumen microflora, and fermentation function of beef cattle through in vitro and in vivo experiments. TAN was evaluated at 0.15% (dry matter basis, DM) in the in vitro experiment and 0.20% (DM basis) in the animal feeding experiment. The in vitro results revealed that compared with control (CON, basal diet without TAN), the addition of TAN significantly increased the cumulative gas production and asymptotic gas production per 0.20 g dry matter substrate (p < 0.01), with a tendency to reduce methane concentration after 96 h of fermentation (p = 0.10). Furthermore, TAN supplementation significantly suppressed the relative abundance of Methanosphaera and Methanobacteriaceae in the fermentation fluid (LDA > 2.50, p < 0.05). The in vivo experiment showed that compared with CON, the dietary TAN significantly improved average daily gain (+0.15 kg/d), dressing percent (+1.30%), net meat percentage (+1.60%), and serum glucose concentration (+23.35%) of beef cattle (p < 0.05), while it also significantly reduced hepatic malondialdehyde contents by 25.69% (p = 0.02). Moreover, the TAN group showed significantly higher alpha diversity (p < 0.05) and increased relative abundance of Ruminococcus and Saccharomonas (LDA > 2.50, p < 0.05), while the relative abundance of Prevotellaceae in rumen microbial community was significantly decreased (p < 0.05) as compared to that of the CON group. In conclusion, the dietary supplementation of TAN could improve the growth and slaughter performance and health status of beef cattle, and these favorable effects might be attributed to its ability to alleviate liver lipid peroxidation, enhance glucose metabolism, and promote a balanced rumen microbiota for optimal fermentation.

4.
Antioxidants (Basel) ; 12(8)2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37627487

RESUMO

The research aimed to investigate the suitable drinking water temperature in winter and its effect on the growth performance, antioxidant capacity, and rumen fermentation function of beef cattle. A total of 40 beef cattle (640 ± 19.2 kg) were randomly divided into five treatments with eight cattle in each treatment raised in one pen according to initial body weight. Each treatment differed only in the temperature of drinking water, including the room-temperature water and four different heat water groups named RTW, HW_1, HW_2, HW_3, and HW_4. The measured water temperatures were 4.39 ± 2.546 °C, 10.6 ± 1.29 °C, 18.6 ± 1.52 °C, 26.3 ± 1.70 °C, and 32.5 ± 2.62 °C, respectively. The average daily gain (ADG) showed a significant linear increase during d 0 to 60 and a quadratic increase during d 31 to 60 with rising water temperature (p < 0.05), and the highest ADG of 1.1911 kg/d was calculated at a water temperature of 23.98 °C (R2 = 0.898). The average rectal temperature on d 30 (p = 0.01) and neutral detergent fiber digestibility (p < 0.01) increased linearly with increasing water temperature. Additionally, HW_2 reduced serum triiodothyronine, thyroxine, and malondialdehyde (p < 0.05), and increased serum total antioxidant capacity (p < 0.05) compared with RTW. Compared with HW_2, RTW had unfavorable effects on ruminal propionate, total volatile fatty acids, and cellulase concentrations (p < 0.05), and lower relative mRNA expression levels of claudin-4 (p < 0.01), occludin (p = 0.02), and zonula occludens-1 (p = 0.01) in the ruminal epithelium. Furthermore, RTW had a higher abundance of Prevotella (p = 0.04), Succinivibrionaceae_UCG-002 (p = 0.03), and Lachnospiraceae_UCG-004 (p = 0.03), and a lower abundance of Bifidobacteriaceae (p < 0.01) and Marinilabiliaceae (p = 0.05) in rumen compared to HW_2. Taken together, heated drinking water in cold climates could positively impact the growth performance, nutrient digestibility, antioxidant capacity, and rumen fermentation function of beef cattle. The optimal water temperature for maximizing ADG was calculated to be 23.98 °C under our conditions. Ruminal propionate and its producing bacteria including Prevotella, Succinivibrionaceae, and Lachnospiraceae might be important regulators of rumen fermentation of beef cattle drinking RTW under cold conditions.

6.
Magn Reson Imaging ; 99: 110-122, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36796460

RESUMO

Decreasing magnetic resonance (MR) image acquisition times can potentially make MR examinations more accessible. Prior arts including the deep learning models have been devoted to solving the problem of long MRI imaging time. Recently, deep generative models have exhibited great potentials in algorithm robustness and usage flexibility. Nevertheless, none of existing schemes can be learned from or employed to the k-space measurement directly. Furthermore, how do the deep generative models work well in hybrid domain is also worth being investigated. In this work, by taking advantage of the deep energy-based models, we propose a k-space and image domain collaborative generative model to comprehensively estimate the MR data from under-sampled measurement. Equipped with parallel and sequential orders, experimental comparisons with the state-of-the-arts demonstrated that they involve less error in reconstruction accuracy and are more stable under different acceleration factors.


Assuntos
Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Algoritmos , Tempo , Aceleração
8.
FEMS Microbiol Lett ; 369(1)2022 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-36370448

RESUMO

Tuberculosis (TB), caused by Mycobacterium tuberculosis (MTB), is a serious contagious disease. MTB-encoded small regulatory RNA (sRNA) MTS2823 was reported to be upregulated in the plasma of TB patients. Nevertheless, whether MTS2823 is implicated in MTB drug resistance is unclear. Human macrophage cell line THP-1 was infected with the drug-susceptible strain H37Rv or the multidrug-resistant (MDR) strain 8462. Colony-forming unit assay was implemented for evaluating intracellular growth of the MTB strains. Enzyme-linked immunosorbent assay was used for measurement of inflammatory cytokines. Real-time quantitative polymerase chain reaction was utilized to assess MTS2823 and recombinase A (recA) expression in strains 8462 and H37Rv. Nitric oxide (NO) production in the MDR strain-infected THP-1 cells was measured. In this study, MTS2823 was found to display a low level in the MDR strain. Overexpressing MTS2823 promoted intracellular growth of the MDR strain and inhibited inflammatory cytokine and NO production in infected THP-1 cells. RecA might be a target of MTS2823 in the MDR strain. Overall, MTB-encoded sRNA MTS2823 displays a low level and regulates the growth of the MDR strain in THP-1 cells by modulating recA.


Assuntos
Mycobacterium tuberculosis , Tuberculose Resistente a Múltiplos Medicamentos , Tuberculose , Humanos , Tuberculose Resistente a Múltiplos Medicamentos/genética , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Antituberculosos/farmacologia , Macrófagos/microbiologia , Citocinas/genética
9.
Artigo em Inglês | MEDLINE | ID: mdl-36204119

RESUMO

Objective: To explore the predictive value of single-index screening or multi-index combined screening for preeclampsia. Methods: From January 1, 2019, to December 31, 2021, pregnant women with a singleton pregnancy who had been regularly checked in each center since the first trimester (between 11 and 14 weeks of gestation) were retrieved from multiple participating centers. The risk calculation software LifeCycle 7.0 was used to calculate the risk values before 32 weeks, 34 weeks, and 37 weeks of gestation, and through a receiver operating characteristic (ROC) curve analysis, the predictive values of pregnancy-associated protein A (PAPP-A), the placental growth factor (PLGF), the mean arterial pressure (MAP), the uterine artery pulsatility index (UTPI), or a combined multi-index were calculated for preeclampsia. Results: Finally, 22 pregnant women developed preeclampsia, and the area under the ROC curve of the PAPP-A + PLGF + MAP + UTPI combined screening program was greater than that of other screening programs before 37 weeks of gestation (AUC = 0.975, 0.946, or 0.840 for <32 weeks, <34 weeks, or <37 weeks, respectively). At 32 weeks, the Youden index was at its maximum. Conclusion: PAPP-A + PLGF + MAP + UTPI combined screening is the optimal screening mode for preeclampsia screening before 37 weeks of gestation, and the combined prediction using multiple indicators in early pregnancy is more suitable for predicting the risk of early-onset preeclampsia.

10.
Am J Transl Res ; 14(9): 5965-5981, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36247298

RESUMO

OBJECTIVE: The lateral mass joint plays an important role in maintaining the mechanical stability of the subaxial cervical spine. We first performed a three-dimensional finite element (FE) biomechanical study to evaluate the local mechanical stability of subaxial cervical fracture dislocations after anterior-only fixation for lateral mass injuries of varying severity. METHODS: A three-dimensional FE model of the subaxial cervical spine with simple anterior fixation for C5-6 fracture dislocation was reconstructed. According to their different morphological characteristics of unilateral lateral mass injuries, the lateral mass injury was divided into six types. The range of motion (ROM) of each part and the stress of the cage, each intervertebral disc, titanium plate, and screw stress were recorded. RESULTS: The ROM of C3-4, C4-5, C5-6, and C6-7 in type 4 was higher than that of the other five types. The maximum equivalent stress on C4-5 intervertebral discs, titanium plates, and screws in type 4 under various sports loads was higher than that produced by the other load types. In the stress cloud diagram of the front titanium plate and screws, the degree of stress was the highest in type 4. Stress placed on each part of the model, from high to low, was as follows: plate, screw, C6, C5, and C7. CONCLUSION: Greater injury severity is associated with higher stress on the plate and screw with exercise loads. Type 4 lateral mass injuries, characterized by ipsilateral pedicle and lamina junction fractures, significantly affected biomechanical stability after simple anterior fixation.

11.
Sci Rep ; 12(1): 7849, 2022 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-35550581

RESUMO

An in-fiber Michelson interferometer (MI)-based inclinometer, which consists of misalignment-spliced fiber with end coating, is proposed and experimentally demonstrated. The incident light divided at the misalignment-spliced joint is reflected at the end coating, and then re-coupled into the fiber core. Due to the phase difference between the core mode and the [Formula: see text] cladding mode, a typical MI is formed. The fiber near the misalignment-spliced joint is inserted in two capillary quartz tubes. The tilt of the capillary quartz tube leads to a significant deformation and curvature of the misalignment-spliced joint, which causes the wavelength and intensity of the MI spectrum to change. The experimental results indicate a good response within the angle range of 0°-50°. Both the wavelength modulation and intensity modulation are realized, with sensitivities of 0.55 nm/deg and 0.17 dB/deg, respectively. Moreover, the sensor shows a strong orientation dependence due to the asymmetric structure in the misalignment-spliced joint.

12.
Appl Math Lett ; 125: 107783, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34776608

RESUMO

The 2019 novel coronavirus (COVID-19) emerged at the end of 2019 has a great influence on the health and lives of people all over the world. The spread principle is still unclear. This paper considers a novel evolution model of COVID-19 in terms of an integral-differential equation, involving vaccination effect and the incubation of COVID-19. The proposed mathematical model is rigorously analyzed on its asymptotic behavior with new probability functions, showing the final spread tendency. Moreover, our model is also verified numerically by the practical epidemic data of COVID-19 in Yangzhou from July to August 2021.

13.
Molecules ; 26(22)2021 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-34834131

RESUMO

A novel soluble copolymer poly(S-MVT) was synthesized using a relatively quick one-pot solvent-free method, inverse vulcanization. Both of the two raw materials are sustainable, i.e., elemental sulfur is a by-product of the petroleum industry and 4-Methyl-5-vinylthiazole (MVT) is a natural monoene compound. The microstructure of poly(S-MVT) was characterized by FT-IR, 1H NMR, XPS spectroscopy, XRD, DSC SEM, and TEM. Test results indicated that the copolymers possess protonated thiazole nitrogen atoms, meso/macroporous structure, and solubility in tetrahydrofuran and chloroform. Moreover, the improved electronic properties of poly(S-MVT) relative to elemental sulfur have also been investigated by density functional theory (DFT) calculations. The copolymers are utilized successfully as the cathode active material in Li-S batteries. Upon employment, the copolymer with 15% MVT content provided good cycling stability at a capacity of ∼514 mA h g-1 (based on the mass of copolymer) and high Coulombic efficiencies (∼100%) over 100 cycles, as well as great rate performance.

14.
Environ Toxicol ; 36(11): 2256-2265, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34355838

RESUMO

Acute myocardial infarction (AMI) is one of the most common and serious cardiovascular diseases. With high morbidity and mortality, AMI has attracted the most attention. Emerging studies indicated that long noncoding RNAs (lncRNAs) play an important role in the progression of AMI. However, the role of NORAD in AMI remained unclear. The current study aimed to investigate the function and mechanism of NORAD in AMI. Bioinformatics tools and a wide range of assays including RT-qPCR, flow cytometry, TTC staining, western blot, luciferase reporter and caspase-3 activity assays were conducted to investigate the function and mechanism of NORAD in AMI. We found out that NORAD was significantly upregulated in AMI rats. Knockdown of NORAD alleviated H9c2 cell injury by reducing apoptosis and decreasing expression levels of fibrogenic factors. In addition, NORAD inhibition ameliorated AMI in a rat model by decreasing infarct size and fibrosis. We confirmed that NORAD bound to miR-577, which was downregulated in ischemia-reperfusion (I/R) rats and hypoxia-exposed H9c2 cells. Additionally, miR-577 combined with the 3'UTR of COBLL1, which was upregulated in I/R rats and hypoxia-exposed H9c2 cells. At last, rescue assay validated that the suppressive effects of NORAD knockdown on apoptosis and expression levels of fibrogenic factors were counteracted by COBLL1 overexpression. Overall, NORAD aggravates acute myocardial infarction by promoting fibrosis and apoptosis via the miR-577/COBLL1 axis. This novel discovery suggested that NORAD may serve as a potential therapeutic target for AMI patients.


Assuntos
MicroRNAs , Infarto do Miocárdio , RNA Longo não Codificante , Animais , Apoptose , Linhagem Celular , Fibrose , MicroRNAs/genética , Infarto do Miocárdio/genética , RNA Longo não Codificante/genética , Ratos , Fatores de Transcrição
15.
J Orthop Surg Res ; 16(1): 476, 2021 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-34344407

RESUMO

BACKGROUND: Vertebral augmentation (VA) techniques are used to treat acute osteoporotic vertebral compression fractures (OVCFs). However, the incidence of recurrent vertebral fractures after VA is controversial. Various factors have been discussed in the literature, but no convincing study on the quality of paraspinal muscles has been reported. The purposes of this study were to evaluate the changes in paraspinal muscles and discuss the relationship between paraspinal muscle degeneration and vertebral refractures after percutaneous kyphoplasty (PKP). METHODS: This retrospective study was conducted in patients who underwent PKP for an initial OVCF between July 2017 and August 2018. Patients were followed up and categorized in the refractured or non-refractured group. A final magnetic resonance imaging (MRI) scan and a preoperative MRI scan were used to determine the measurements. The paraspinal muscles at the mid-height level of the initial fractured vertebral body were measured using regions of interest (ROIs), including the cross-sectional area (CSA) and signal intensity (SI). The changes in the observed data were compared between the groups using rank-sum tests. RESULTS: Overall, 92 patients were enrolled in the study; 33 of them sustained vertebral refractures during the follow-up and the other 59 patients did not. There were no significant differences in terms of sex, age, preoperative bone mineral density, and body mass index between the groups (all, P > 0.05). The refractured group had a significantly higher decrease in the ROI-CSA and CSA/SI, and a higher increase in ROI-SI, compared with the preoperative data (all, P < 0.05). CONCLUSIONS: The quality of paraspinal muscles significantly decreased in patients with new OVCFs after PKP. This brings a new perspective to the study of postoperative recurrent fractures; patients and physicians need to pay more attention to the efficacy of bed rest and bracing.


Assuntos
Fraturas por Compressão , Cifoplastia , Imageamento por Ressonância Magnética , Fraturas por Osteoporose , Fraturas da Coluna Vertebral , Fraturas por Compressão/diagnóstico por imagem , Fraturas por Compressão/cirurgia , Humanos , Cifoplastia/efeitos adversos , Atrofia Muscular , Fraturas por Osteoporose/diagnóstico por imagem , Fraturas por Osteoporose/cirurgia , Músculos Paraespinais/diagnóstico por imagem , Estudos Retrospectivos , Fraturas da Coluna Vertebral/diagnóstico por imagem , Fraturas da Coluna Vertebral/cirurgia
16.
J Cardiovasc Pharmacol ; 78(4): 622-629, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34282068

RESUMO

ABSTRACT: Doxorubicin (DOX) is a chemotherapeutic drug for treating various cancers. However, the DOX-induced cardiotoxicity greatly limits its clinical application. MicroRNAs are emerged as critical mediators of cardiomyocyte injury. This work explored the function of miR-215-5p in the regulation of DOX-induced mouse HL-1 cardiomyocyte injury. An in vitro model of DOX-treated cardiotoxicity was established in cardiac mouse cell line HL-1. Gene expression was measured by reverse transcription quantitative polymerase chain reaction. Cell viability was detected using CCK-8. Cell death and apoptosis were tested using transferase-mediated deoxyuridine triphosphate-biotin nick end labeling (TUNEL), flow cytometry, and caspase-3/7 activity assays. Luciferase reporter assay was used to examine the target of miR-215-5p. We found that DOX induced cardiomyocyte injury and upregulated miR-215-5p in HL-1 cells. Inhibition of miR-215-5p attenuated DOX-induced cardiomyocyte death and apoptosis in vitro. Mechanistical experiments indicated that zinc finger E-box-binding homeobox (ZEB2) was targeted by miR-215-5p. In addition, ZEB2 expression was reduced in DOX-treated HL-1 cells. Rescue assays indicated that ZEB2 knockdown reversed the effects of miR-215-5p inhibition. In conclusion, miR-215-5p inhibition protects HL-1 cells against DOX-induced injury by upregulating ZEB2 expression.


Assuntos
Antibióticos Antineoplásicos/toxicidade , Apoptose/efeitos dos fármacos , Doxorrubicina/toxicidade , MicroRNAs/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Homeobox 2 de Ligação a E-box com Dedos de Zinco/metabolismo , Animais , Proteínas Reguladoras de Apoptose/metabolismo , Cardiotoxicidade , Linhagem Celular , Regulação da Expressão Gênica , Camundongos , MicroRNAs/genética , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Transdução de Sinais , Homeobox 2 de Ligação a E-box com Dedos de Zinco/genética
17.
BMC Cancer ; 21(1): 108, 2021 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-33530966

RESUMO

BACKGROUND: Currently, the choice of treatment for individuals with metastatic soft tissue sarcomas (MSTS) presents a significant challenge to clinicians. The aim of this retrospective study was to assess the efficacy and safety of nivolumab plus ipilimumab (NPI) versus nivolumab alone (NIV) in individuals with treatment-naive programmed death-ligand 1 (PD-L1) positive MSTS. METHODS: Prospectively maintained databases were reviewed from 2013 to 2018 to assess individuals with treatment-naive PD-L1 MSTS who received NPI (nivolumab 3 mg/kg and ipilimumab 1 mg/kg every 3 weeks for 4 doses followed by nivolumab 3 mg/kg every 2 weeks) or NIV (3 mg/kg every 2 weeks) until disease progression, withdrawal, unendurable [AEs], or death. The co-primary endpoints were overall survival (OS) and progression-free survival (PFS). RESULTS: The median follow-up was 16.0 months (IQR 14.4-18.5) after targeted intervention. The median OS was 12.2 months (95% confidence interval [CI], 6.1-13.7) and 9.2 months (95% CI, 4.2-11.5) for the NPI and NIV groups, respectively (hazard ratio [HR] 0.49, 95% CI, 0.33-0.73; p=0.0002); the median PFS was 4.1 months (95% CI, 3.2-4.5) and 2.2 months (95% CI, 1.1-3.4) for the NPI and NIV groups, respectively (HR 0.51, 95% CI, 0.36-0.71; p< 0.0001). Key grade 3-5 AEs occurred more frequently in the NPI group than in the NIV group (94 [72.9%] for NPI vs. 35 [27.1%], p< 0.001). CONCLUSIONS: For treatment-naive PD-L1 positive MSTS, NPI seems to be less tolerated but has a greater survival advantage than NIV as the primary therapy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Antígeno B7-H1/metabolismo , Sarcoma/tratamento farmacológico , Adulto , Antígeno B7-H1/antagonistas & inibidores , Antígeno B7-H1/imunologia , Feminino , Seguimentos , Humanos , Ipilimumab/administração & dosagem , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Nivolumabe/administração & dosagem , Prognóstico , Estudos Prospectivos , Estudos Retrospectivos , Sarcoma/imunologia , Sarcoma/patologia , Taxa de Sobrevida
18.
Appl Math Model ; 89: 1965-1982, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32836696

RESUMO

The 2019 novel coronavirus (COVID-19) emerged at the end of 2019 has a great impact on China and all over the world. The transmission mechanism of COVID-19 is still unclear. Except for the initial status and the imported cases, the isolation measures and the medical treatments of the infected patients have essential influences on the spread of COVID-19. In this paper, we establish a mathematical model for COVID-19 transmission involving the interactive effect of various factors for the infected people, including imported cases, isolating rate, diagnostic rate, recovery rate and also the mortality rate. Under the assumption that the random incubation period, the cure period and the diagnosis period are subject to the Weibull distribution, the quantity of daily existing infected people is finally governed by a linear integral-differential equation with convolution kernel. Based on the asymptotic behavior and the quantitative analysis on the model, we rigorously prove that, for limited external input patients, both the quantity of infected patients and its variation ratio will finally tend to zero, if the infected patients are sufficiently isolated or the infection rate is small enough. Finally, numerical performances for the proposed model as well as the comparisons between our simulations and the clinical data of the city Wuhan and Italy are demonstrated, showing the validity of our model with suitably specified model parameters.

19.
J Cell Mol Med ; 25(1): 244-258, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33219747

RESUMO

miRNA-mediated pyroptosis play crucial effects in the development of myocardial ischaemia/reperfusion (I/R) injury (MIRI). Piperine (PIP) possesses multiple pharmacological effects especially in I/R condition. This study focuses on whether PIP protects MIRI from pyroptosis via miR-383-dependent pathway. Rat MIRI model was established by 30 minutes of LAD ligation and 4 hours of reperfusion. Myocardial enzymes, histomorphology, structure and function were detected to evaluate MIRI. Recombinant adenoviral vectors for miR-383 overexpression or miR-383 silencing or RP105 knockdown were constructed, respectively. Luciferase reporter analysis was used to confirm RP105 as a target of miR-383. Pyroptosis-related markers were measured by Western blotting assay. The results showed that I/R provoked myocardial injury, as shown by the increases of LDH/CK releases, infarcted areas and apoptosis as well as worsened function and structure. Pyroptosis-related mediators including NLRP3, cleaved caspase-1, cleaved IL-1ß and IL-18 were also reinforced after MIRI. However, PIP treatment greatly ameliorated MIRI in parallel with pyroptotic repression. In mechanistic studies, MIRI-caused elevation of miR-383 and decrease of RP105/PI3K/AKT pathway were reverted by PIP treatment. Luciferase reporter assay confirmed RP105 as a miR-383 target. miR-383 knockdown ameliorated but miR-383 overexpression facilitated pyroptosis and MIRI. Moreover, the anti-pyroptotic effect from miR-383 silencing was verified to be relied on the RP105/PI3K/AKT signalling pathway. Additionally, our present study further indicated the miR-383/RP105/AKT-dependent approach resulting from PIP administration against pyroptosis in MIRI. Therefore, PIP treatment attenuates MIRI and pyroptosis by regulating miR-383/RP105/AKT pathway, and it may provide a therapeutic manner for the treatment of MIRI.


Assuntos
Alcaloides/farmacologia , Antígenos CD/metabolismo , Benzodioxóis/farmacologia , MicroRNAs/metabolismo , Traumatismo por Reperfusão Miocárdica/genética , Traumatismo por Reperfusão Miocárdica/patologia , Fosfatidilinositol 3-Quinases/metabolismo , Piperidinas/farmacologia , Alcamidas Poli-Insaturadas/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Piroptose , Animais , Cardiotônicos/farmacologia , Masculino , MicroRNAs/genética , Piroptose/efeitos dos fármacos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos
20.
Int J Mol Med ; 46(6): 2260-2270, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33125085

RESUMO

The aim of the present study was to assess the activation of nuclear factor­κB (NF­κB) in the infrapatellar fat pads (IPFPs) of obese patients with knee osteoarthritis (KOA). For this purpose, 32 patients (22 obese patients with KOA and 10 patients with KOA with a healthy weight) treated with total knee arthroplasty (TKA) were selected. The expression levels of pro­inflammatory cytokines and adipocytokines, and the activation of NF­κB were detected in both the cases and controls by enzyme­linked immunosorbent assay (ELISA), western blot analysis and immunohistochemistry where appropriate. SPSS 18.0 software was used for statistical analysis to determine the correlation between obesity and the detected cytokine levels. It was found that in patients with KOA, the expression of leptin in the synovial fluid positively correlated with body mass index (BMI; P<0.05), and the expression of interleukin (IL)­6 in serum significantly correlated with the IL­1ß, leptin and tumor necrosis factor (TNF)­α levels (P<0.05). Furthermore, the expression of inflammatory cytokines and adipocytokines in IPFPs differed significantly between the obese and non­obese patients with KOA (P<0.05). By evaluating the expression of IKKß and IκBα and the nuclear translocation ability of p­p65, it was concluded that NF­κB signaling was activated to a higher degree in the IPFP tissues of obese patients with KOA than in those of patients with KOA with a healthy weight. On the whole, the findings of the present study suggested that the NF­κB signaling pathway was activated and that there were changes in the expression in levels of inflammatory cytokines and adipocytokines in the IPFP tissues of obese patients with KOA.


Assuntos
Tecido Adiposo/patologia , Articulação do Joelho/patologia , NF-kappa B/metabolismo , Obesidade/complicações , Obesidade/patologia , Osteoartrite do Joelho/complicações , Osteoartrite do Joelho/patologia , Transdução de Sinais , Índice de Massa Corporal , Estudos de Casos e Controles , Citocinas/metabolismo , Feminino , Humanos , Quinase I-kappa B/metabolismo , Mediadores da Inflamação/metabolismo , Masculino , Pessoa de Meia-Idade , Inibidor de NF-kappaB alfa/genética , Inibidor de NF-kappaB alfa/metabolismo , Fator de Transcrição RelA/metabolismo
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