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1.
Adv Sci (Weinh) ; 11(17): e2307034, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38353386

RESUMO

Exchange bias is extensively studied and widely utilized in spintronic devices, such as spin valves and magnetic tunnel junctions. 2D van der Waals (vdW) magnets, with high-quality interfaces in heterostructures, provide an excellent platform for investigating the exchange bias effect. To date, intrinsic modulation of exchange bias, for instance, via precise manipulation of the magnetic phases of the antiferromagnetic layer, is yet to be fully reached, owing partly to the large exchange fields of traditional bulk antiferromagnets. Herein, motivated by the low-field spin-flop transition of a 2D antiferromagnet, CrPS4, exchange bias is explored by modulating the antiferromagnetic spin-flop phase transition in all-vdW magnetic heterostructures. The results demonstrate that undergoing the spin-flop transition during the field cooling process, the A-type antiferromagnetic ground state of CrPS4 turns into a canted antiferromagnetic one, therefore, it reduces the interfacial magnetic coupling and suppresses the exchange bias. Via conducting different cooling fields, one can select the exchange bias effect switching among the "ON", "depressed", and "OFF" states determined by the spin flop of CrPS4. This work provides an approach to intrinsically modulate the exchange bias in all-vdW heterostructures and paves new avenues to design and manipulate 2D spintronic devices.

2.
Front Endocrinol (Lausanne) ; 15: 1325317, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38370357

RESUMO

Osteoporosis (OP) is a systemic skeletal disorder characterized by reduced bone mass and structural deterioration of bone tissue, resulting in heightened vulnerability to fractures due to increased bone fragility. This condition primarily arises from an imbalance between the processes of bone resorption and formation. Mitochondrial dysfunction has been reported to potentially constitute one of the most crucial mechanisms influencing the pathogenesis of osteoporosis. In essence, mitochondria play a crucial role in maintaining the delicate equilibrium between bone formation and resorption, thereby ensuring optimal skeletal health. Nevertheless, disruption of this delicate balance can arise as a consequence of mitochondrial dysfunction. In dysfunctional mitochondria, the mitochondrial electron transport chain (ETC) becomes uncoupled, resulting in reduced ATP synthesis and increased generation of reactive oxygen species (ROS). Reinforcement of mitochondrial dysfunction is further exacerbated by the accumulation of aberrant mitochondria. In this review, we investigated and analyzed the correlation between mitochondrial dysfunction, encompassing mitochondrial DNA (mtDNA) alterations, oxidative phosphorylation (OXPHOS) impairment, mitophagy dysregulation, defects in mitochondrial biogenesis and dynamics, as well as excessive ROS accumulation, with regards to OP (Figure 1). Furthermore, we explore prospective strategies currently available for modulating mitochondria to ameliorate osteoporosis. Undoubtedly, certain therapeutic strategies still require further investigation to ensure their safety and efficacy as clinical treatments. However, from a mitochondrial perspective, the potential for establishing effective and safe therapeutic approaches for osteoporosis appears promising.


Assuntos
Doenças Mitocondriais , Osteoporose , Humanos , Espécies Reativas de Oxigênio , Estudos Prospectivos , Mitocôndrias/patologia , DNA Mitocondrial/genética , Doenças Mitocondriais/genética , Osteoporose/terapia , Osteoporose/patologia
3.
Materials (Basel) ; 16(23)2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-38068018

RESUMO

In the present work, Fe88Zr8-xSmxB4 (x = 2, 4) amorphous alloys (AAs) were successfully synthesized into the shape of 40-micrometer-thick ribbons and their magnetic properties were measured. The Fe88Zr8-xSmxB4 (x = 2, 4) AAs exhibited a rather high maximum magnetic entropy change (-ΔSmpeak): ~3.53 J/(K × kg) near 317 K for x = 2 and ~3.79 J/(K × kg) near 348 K for x = 4 under 5 T. The effects of a Sm substitution for Zr on the Curie temperature (Tc) and -ΔSmpeak were studied and compared to those of Nd and Pr substitutions, for the purpose of revealing the mechanism involved in more detail.

4.
Biomed Pharmacother ; 169: 115839, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37976889

RESUMO

Copper-induced cell death, also known as cuproptosis, is distinct from other types of cell death such as apoptosis, necrosis, and ferroptosis. It can trigger the accumulation of lethal reactive oxygen species, leading to the onset and progression of aging. The significant increases in copper ion levels in the aging populations confirm a close relationship between copper homeostasis and vascular aging. On the other hand, vascular aging is also closely related to the occurrence of various cardiovascular diseases throughout the aging process. However, the specific causes of vascular aging are not clear, and different living environments and stress patterns can lead to individualized vascular aging. By exploring the correlations between copper-induced cell death and vascular aging, we can gain a novel perspective on the pathogenesis of vascular aging and enhance the prognosis of atherosclerosis. This article aims to provide a comprehensive review of the impacts of copper homeostasis on vascular aging, including their effects on endothelial cells, smooth muscle cells, oxidative stress, ferroptosis, intestinal flora, and other related factors. Furthermore, we intend to discuss potential strategies involving cuproptosis and provide new insights for copper-related vascular aging.


Assuntos
Cobre , Células Endoteliais , Cobre/farmacologia , Morte Celular , Apoptose , Homeostase
5.
J Econ Entomol ; 116(5): 1830-1837, 2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37738568

RESUMO

The fall armyworm, Spodoptera frugiperda (Lepidoptera: Noctuidae), is a cosmopolitan pest that exploits more than 350 host plants, including economically important crops such as corn, cotton and rice. Control of S. frugiperda largely relies on transgenic crops producing insecticidal proteins from Bacillus thuringiensis (Bt) and spraying synthetic insecticides. Here, we established the susceptibility and diagnostic concentration for 2 Bt toxins and 5 newer insecticides in invasive populations of S. frugiperda from southeastern China. Concentrations causing 50% mortality (LC50) in ten field populations sampled in 2022 ranged from 2.13 to 19.29 and 22.43 to 71.12 ng/cm2 for Cry1Fa and Vip3Aa, and 0.83 to 5.30, 2.83 to 9.94, 0.04 to 0.23, 4.59 to 8.40, and 1.49 to 6.79 mg/liter for chlorantraniliprole, chlorfenapyr, emamectin benzoate, indoxacarb, and spinosad, respectively. Relative to the susceptible strain YJ-19, the largest resistance ratio in the field populations was 5.1, 1.6, 6.2, 3.9, 4.6, 2.2, and 3.6 for Cry1Fa, Vip3Aa, chlorantraniliprole, chlorfenapyr, emamectin benzoate, indoxacarb, and spinosad, respectively, indicating that the field populations were generally susceptible to these Bt toxins and insecticides. Based on the pooled response of the field populations, the diagnostic concentration for resistance monitoring, estimated as ca. twice the LC99, was 400 and 1,500 ng/cm2 for Cry1Fa and Vip3Aa, and 2, 40, 60, 60, and 100 mg/liter for emamectin benzoate, chlorantraniliprole, chlorfenapyr, spinosad, and indoxacarb, respectively. These results provide useful information for monitoring resistance to key Bt toxins and insecticides for the control of S. frugiperda in China.

6.
Front Pharmacol ; 14: 1203767, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37441527

RESUMO

A metabolic bone disorder called osteoporosis is characterized by decreased bone mass and compromised microarchitecture. This condition can deteriorate bones and raise the risk of fractures. The two main causes of osteoporosis are an increase in osteoclast activity or quantity and a decrease in osteoblast viability. Numerous mechanisms, including estrogen shortage, aging, chemical agents, and decreased mechanical loads, have been linked to osteoporosis. Inflammation and oxidative stress have recently been linked to osteoporosis, according to an increasing number of studies. The two primary medications used to treat osteoporosis at the moment are bisphosphonates and selective estrogen receptor modulators (SERMs). These medications work well for osteoporosis brought on by aging and estrogen deprivation, however, they do not target inflammation and oxidative stress-induced osteoporosis. In addition, these drugs have some limitations that are attributed to various side effects that have not been overcome. Traditional Chinese medicine (TCM) has been applied in osteoporosis for many years and has a high safety profile. Therefore, in this review, literature related to botanical drugs that have an effect on inflammation and oxidative stress-induced osteoporosis was searched for. Moreover, the pharmacologically active ingredients of these herbs and the pathways were discussed and may contribute to the discovery of more safe and effective drugs for the treatment of osteoporosis.

7.
Front Endocrinol (Lausanne) ; 14: 1135181, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37214253

RESUMO

Osteoporosis is an age-related disease of bone metabolism marked by reduced bone mineral density and impaired bone strength. The disease causes the bones to weaken and break more easily. Osteoclasts participate in bone resorption more than osteoblasts participate in bone formation, disrupting bone homeostasis and leading to osteoporosis. Currently, drug therapy for osteoporosis includes calcium supplements, vitamin D, parathyroid hormone, estrogen, calcitonin, bisphosphates, and other medications. These medications are effective in treating osteoporosis but have side effects. Copper is a necessary trace element in the human body, and studies have shown that it links to the development of osteoporosis. Cuproptosis is a recently proposed new type of cell death. Copper-induced cell death regulates by lipoylated components mediated via mitochondrial ferredoxin 1; that is, copper binds directly to the lipoylated components of the tricarboxylic acid cycle, resulting in lipoylated protein accumulation and subsequent loss of iron-sulfur cluster proteins, leading to proteotoxic stress and eventually cell death. Therapeutic options for tumor disorders include targeting the intracellular toxicity of copper and cuproptosis. The hypoxic environment in bone and the metabolic pathway of glycolysis to provide energy in cells can inhibit cuproptosis, which may promote the survival and proliferation of various cells, including osteoblasts, osteoclasts, effector T cells, and macrophages, thereby mediating the osteoporosis process. As a result, our group tried to explain the relationship between the role of cuproptosis and its essential regulatory genes, as well as the pathological mechanism of osteoporosis and its effects on various cells. This study intends to investigate a new treatment approach for the clinical treatment of osteoporosis that is beneficial to the treatment of osteoporosis.


Assuntos
Apoptose , Reabsorção Óssea , Osteoporose , Humanos , Reabsorção Óssea/metabolismo , Cobre , Osteoclastos/metabolismo , Osteoporose/patologia , Hormônio Paratireóideo/metabolismo
8.
IEEE Trans Cybern ; 53(12): 7881-7894, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37022073

RESUMO

Iterative learning model predictive control (ILMPC) has been recognized as an excellent batch process control strategy for progressively improving tracking performance along trials. However, as a typical learning-based control method, ILMPC generally requires the strict identity of trial lengths to implement 2-D receding horizon optimization. The randomly varying trial lengths extensively existing in practice can result in the insufficiency of learning prior information, and even the suspension of control update. Regarding this issue, this article embeds a novel prediction-based modification mechanism into ILMPC, to adjust the process data of each trial into the same length by compensating the data of absent running periods with the predictive sequences at the end point. Under this modification scheme, it is proved that the convergence of the classical ILMPC is guaranteed by an inequality condition relative with the probability distribution of trial lengths. Considering the practical batch process with complex nonlinearity, a 2-D neural-network predictive model with parameter adaptability along trials is established to generate highly matched compensation data for the prediction-based modification. To best utilize the real process information of multiple past trials while guaranteeing the learning priority of the latest trials, an event-based switching learning structure is proposed in ILMPC to determine different learning orders according to the probability event with respect to the trial length variation direction. The convergence of the nonlinear event-based switching ILMPC system is analyzed theoretically under two situations divided by the switching condition. The simulations on a numerical example and the injection molding process verify the superiority of the proposed control methods.

9.
Se Pu ; 41(3): 207-223, 2023 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-36861204

RESUMO

Ciwujia injection is commonly used to treat cerebrovascular and central nervous system diseases in clinical practice. It can significantly improve blood lipid levels and endothelial cell function in patients with acute cerebral infarction and promote the proliferation of neural stem cells in cerebral ischemic brain tissues. The injection has also been reported to have good curative effects on cerebrovascular diseases, such as hypertension and cerebral infarction. At present, the material basis of Ciwujia injection remains incompletely understood, and only two studies have reported dozens of components, which were determined using high performance liquid chromatography-quadrupole time-of-flight mass spectrometry (HPLC-Q-TOF MS). Unfortunately, the lack of research on this injection restricts the in-depth study of its therapeutic mechanism.In the present study, a qualitative method based on ultra-high performance liquid chromatography-quadrupole-electrostatic field orbitrap high-resolution mass spectrometry (UHPLC-Q/Orbitrap HRMS) was developed to analyze the chemical components of Ciwujia injection. Separation was performed on a BEH Shield RP18 column (100 mm×2.1 mm, 1.7 µm) using 0.1% formic acid aqueous solution (A) and acetonitrile (B) as the mobile phases, and gradient elution was performed as follows: 0-2 min, 0%B; 2-4 min, 0%B-5%B; 4-15 min, 5%B-20%B; 15-15.1 min, 20%B-90%B; 15.1-17 min, 90%B. The flow rate and column temperature were set to 0.4 mL/min and 30 ℃ respectively. MS1 and MS2 data were acquired in both positive- and negative-ion modes using a mass spectrometer equipped with an HESI source. For data post-processing, a self-built library including component names, molecular formulas, and chemical structures was established by collecting information on the isolated chemical compounds of Acanthopanax senticosus. The chemical components of the injection were identified by comparison with standard compounds or MS2 data in commercial databases or literature based on precise relative molecular mass and fragment ion information. The fragmentation patterns were also considered. For example, the MS2 data of 3-caffeoylquinic acid (chlorogenic acid), 4-caffeoylquinic acid (cryptochlorogenic acid), and 5-caffeoylquinic acid (neochlorogenic acid) were first analyzed. The results indicated that these compounds possessed similar fragmentation behaviors, yielding product ions at m/z 173 and m/z 179 simultaneously. However, the abundance of the product ion at m/z 173 was much higher in 4-caffeoylquinic acid than in 5-caffeoylquinic acid or 3-caffeoylquinic acid, and the fragment signal at m/z 179 was much stronger for 5-caffeoylquinic acid than for 3-caffeoylquinic acid. Four caffeoylquinic acids were identified using a combination of abundance information and retention times. MS2 data in commercial database and literature were also used to identify unknown constituents. For example, compound 88 was successfully identified as possessing a relative molecular mass and neutral losses similar to those of sinapaldehyde using the database, and compound 80 was identified as salvadoraside because its molecular and fragmentation behaviors were consistent with those reported in the literature. A total of 102 constituents, including 62 phenylpropanoids, 23 organic acids, 7 nucleosides, 1 iridoid, and 9 other compounds, were identified. The phenylpropanoids can be further classified as phenylpropionic acids, phenylpropanols, benzenepropanals, coumarins, and lignans. Among the detected compounds, 16 compounds were confirmed using reference compounds and 65 compounds were identified in Ciwujia injection for the first time. This study is the first to report the feasibility of using the UHPLC-Q/Orbitrap HRMS method to quickly and comprehensively analyze the chemical components of Ciwujia injection. The 27 newly discovered phenylpropanoids provide further material basis for the clinical treatment of neurological diseases and new research targets for the in-depth elucidation of the pharmacodynamic mechanism of Ciwujia injection and its related preparations.


Assuntos
Eleutherococcus , Humanos , Cromatografia Líquida de Alta Pressão , Ácido Clorogênico , Eletricidade Estática
10.
Chem Asian J ; 18(4): e202201280, 2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36632721

RESUMO

Gel electrolytes are being intensively explored for aqueous rechargeable zinc-ion batteries, especially towards high performance and multi-functionalities. Water plays a central role on the fundamental properties, interface reaction/interaction, and performance of the gel-type zinc electrolyte. In this review, the influence of water on the physiochemical properties of gel electrolytes is focused on. The correlation between water activity and the fundamental properties of zinc electrolytes is presented. Current approaches and challenges in manipulating water activity and the consequent influence on the electrochemical stability, transport, and interface kinetics of gel electrolytes are summarized. An outlook on approaches to tuning and investigating water activity is provided to shed light on the design of advanced gel electrolytes.

11.
Vet Sci ; 9(12)2022 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-36548814

RESUMO

Rothia nasimurium is a facultative anaerobic Gram-positive coccus belonging to the Rothia genus of the Micrococcaceae family. While Rothia nasimurium is considered an opportunistic pathogen, to date few studies have investigated its pathogenicity and drug resistance. In January 2022, chickens at a poultry farm in China's Xinjiang Uygur Autonomous Region became ill and died. Treatment with commonly used Chinese medicines and antibiotics was ineffective, causing economic losses to the poultry farm. In order to determine the cause of the disease in these poultry farm chickens, the isolation and identification of the pathogens in the livers and other internal organs of the sick and dead chickens were performed. Further, animal pathogenicity tests, antibiotic susceptibility tests, and the detection of antibiotic resistance genes were carried out to analyze the pathogenicity and drug resistance of the identified pathogens. A Gram-positive coccus was isolated from the livers of the diseased chickens. The isolate was resistant to 17 antibiotics, including ciprofloxacin, chloramphenicol, and florfenicol, and was only sensitive to penicillin, amikacin, and tigecycline, to varying degrees. The results of the drug resistance gene testing indicated that the isolated bacterium carried 13 kinds of resistance genes. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, morphological observations, biochemical tests, and 16S rRNA gene sequence analysis were performed on the isolated bacterium, and it was determined that the isolated bacterial strain was Rothia nasimurium. The animal pathogenicity tests showed that the isolate caused feather loss and death in chicks; the clinical symptoms and necropsy lesions of the test chicks were consistent with those observed in the farmed chickens. A review of the literature revealed that, to date, there are no reports of infection with Rothia nasimurium in chickens. Thus, in this study, Rothia nasimurium was isolated from chickens for the first time and an investigation of the biological characteristics of the bacterium was carried out in order to provide a reference for the clinical treatment, prevention, and control of Rothia nasimurium infection.

12.
Exp Gerontol ; 165: 111836, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35598699

RESUMO

Osteoporosis is a bone metabolic disease characterized by reduced bone mass and deterioration of bone tissue microarchitecture, leading to enhanced skeletal fragility and susceptibility to fracture. Unbalanced bone remodeling is the primary pathogenetic factor of osteoporosis, in which osteoclast-mediated bone resorption exceeds osteoblast-mediated bone formation. Bisphosphonates and calcitonin are among the drugs commonly used to treat osteoporosis, in addition to the bone nutrients vitamin D and calcium supplements. The current treatments effectively prevent further bone loss by inhibiting the excessive activation of osteoclasts, accompanied by various degrees of side effects. Iron, one of the trace elements essential for life activities, has recently been recognized as an independent risk factor for osteoporosis. Abnormal iron metabolism increases the incidence of many bone diseases, especially osteoporosis. Iron metabolism does play a key role in bone homeostasis. Ferroptosis is a novel form of cell death that has been discovered in recent years. Its main features include iron overload and the accumulation of ROS. And lipid peroxidation is the key. There are increasing shreds of evidence that ferroptosis is involved in the occurrence and development of osteoporosis, and its regulation can effectively prevent osteoporosis. Therefore, this review further elucidates the role of ferroptosis in osteoporosis based on the mechanism and its relationship with osteoporosis and provides a new idea for treating osteoporosis.


Assuntos
Conservadores da Densidade Óssea , Ferroptose , Osteoporose , Densidade Óssea , Conservadores da Densidade Óssea/farmacologia , Conservadores da Densidade Óssea/uso terapêutico , Humanos , Ferro/metabolismo , Ferro/uso terapêutico , Osteoporose/tratamento farmacológico , Osteoporose/metabolismo
13.
IEEE Trans Cybern ; 52(6): 4147-4160, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33055043

RESUMO

Iterative learning model-predictive control (ILMPC) is very popular in controlling the batch process since it possesses not only the learning ability along batches but also the strong time-domain tracking properties. However, for a fast batch process with strong nonlinear dynamics, the application of the ILMPC is challenging due to the difficulty in balancing the computational efficiency and tracking accuracy. In this article, an efficient iterative learning predictive functional control (ILPFC) is proposed. The original nonlinear system is linearized along the reference trajectory to derive a 2-D tracking-error predictive model. The linearization error is compensated by utilizing the Lipschitz condition so that the objective function can be formulated with the upper bound of the actual tracking error. For enhancing control efficiency, predictive functional control (PFC) is applied in the time domain, which reduces the dimension of the decision variable in order to effectively cut down the computational burden. The stability and convergence of this ILPFC with terminal constraint are analyzed theoretically. Simulations on an unmanned ground vehicle and a typical fast batch reactor verify the effectiveness of the proposed control algorithm.

14.
Front Immunol ; 13: 1095577, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36741390

RESUMO

The cGAS-STING signaling pathway can trigger innate immune responses by detecting dsDNA from outside or within the host. In addition, the cGAS-STING signaling pathway has emerged as a critical mediator of the inflammatory response and a new target for inflammatory diseases. STING activation leads to dimerization and translocation to the endoplasmic reticulum Golgi intermediate compartment or Golgi apparatus catalyzed by TBK1, triggers the production of IRF3 and NF-κB and translocates to the nucleus to induce a subsequent interferon response and pro-inflammatory factor production. Osteoporosis is a degenerative bone metabolic disease accompanied by chronic sterile inflammation. Activating the STING/IFN-ß signaling pathway can reduce bone resorption by inhibiting osteoclast differentiation. Conversely, activation of STING/NF-κB leads to the formation of osteoporosis by increasing bone resorption and decreasing bone formation. In addition, activation of STING inhibits the generation of type H vessels with the capacity to osteogenesis, thereby inhibiting bone formation. Here, we outline the mechanism of action of STING and its downstream in osteoporosis and discuss the role of targeting STING in the treatment of osteoporosis, thus providing new ideas for the treatment of osteoporosis.


Assuntos
Reabsorção Óssea , Osteoporose , Humanos , NF-kappa B/metabolismo , Antivirais , Proteínas de Membrana/metabolismo , Nucleotidiltransferases/metabolismo , Osteoporose/tratamento farmacológico
15.
Front Cell Infect Microbiol ; 11: 675414, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34277468

RESUMO

Frailty is a major public issue that affects the physical health and quality of life of older adults, especially as the population ages. Chronic low-grade inflammation has been speculated to accelerate the aging process as well as the development of age-related diseases such as frailty. Intestinal homeostasis plays a crucial role in healthy aging. The interaction between the microbiome and the host regulates the inflammatory response. Emerging evidence indicates that in older adults with frailty, the diversity and composition structure of gut microbiota are altered. Age-associated changes in gut microbiota composition and in their metabolites contribute to increased gut permeability and imbalances in immune function. In this review, we aim to: identify gut microbiota changes in the aging and frail populations; summarize the role of chronic low-grade inflammation in the development of frailty; and outline how gut microbiota may be related to the pathogenesis of frailty, more specifically, in the regulation of gut-derived chronic inflammation. Although additional research is needed, the regulation of gut microbiota may represent a safe, easy, and inexpensive intervention to counteract the chronic inflammation leading to frailty.


Assuntos
Fragilidade , Microbioma Gastrointestinal , Idoso , Envelhecimento , Humanos , Inflamação , Qualidade de Vida
16.
Exp Gerontol ; 146: 111241, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33453324

RESUMO

Considerable researches implicate that the circadian clock regulates the responsive rhythms of organs and sets the orderly aging process of cells indirectly. It influences an array of diverse biological process including intestinal flora, peripheral inflammatory responses, and redox homeostasis. People with sleep disoders and other kinds of circadian disruptions are prone to have vascular aging earlier. Meanwhile, those people are always faced with chronic vascular inflammation. It has not been elucidated that the specific mechanism of the interaction between the circadian system and early vascular aging. To explore the biphasic relationship between vascular aging and the circadian system, we summarize what is linking circadian clock with early vascular aging through four major prospect: inflammatory process, oxidative stress response, intestinal flora, and cellular senescence. Meanwhile, we discuss the hypothesis that the deterioration of circadian rhythms may exacerbate the process of early vascular aging, leading to the cardiovascular diseases. It will help us to provide new ideas for understanding the process of vascular aging and exploring the possible ways to design personalized chronotherapies.


Assuntos
Relógios Circadianos , Ritmo Circadiano , Estresse Oxidativo , Sono
17.
IEEE Trans Neural Netw Learn Syst ; 32(8): 3377-3390, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32857701

RESUMO

Iterative learning model predictive control (ILMPC) has been recognized as an effective approach to realize high-precision tracking for batch processes with repetitive nature because of its excellent learning ability and closed-loop stability property. However, as a model-based strategy, ILMPC suffers from the unavailability of accurate first principal model in many complex nonlinear batch systems. On account of the abundant process data, nonlinear dynamics of batch systems can be identified precisely along the trials by neural network (NN), making it enforceable to design a data-driven ILMPC. In this article, by using a control-affine feedforward neural network (CAFNN), the features in the process data of the former batch are extracted to form a nonlinear affine model for the controller design in the current batch. Based on the CAFNN model, the ILMPC is formulated in a tube framework to attenuate the influence of modeling errors and track the reference trajectory with sustained accuracy. Due to the control-affine structure, the gradients of the objective function can be analytically computed offline, so as to improve the online computational efficiency and optimization feasibility of the tube ILMPC. The robust stability and the convergence of the data-driven ILMPC system are analyzed theoretically. The simulation on a typical batch reactor verifies the effectiveness of the proposed control method.

18.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 43(5): 494-499, 2018 May 28.
Artigo em Chinês | MEDLINE | ID: mdl-29886464

RESUMO

OBJECTIVE: To observe ulcer characteristics of Crohn's disease under double balloon enteroscopy, and to evaluate the correlation between endoscopic severity and clinical manifestations.
 Methods: A prospective, observational study from July 2015 to December 2016 in the Third Xiangya Hospital, Central South University, we selected 45 patients with positive double-balloon enteroscopy (DBE) and confirmed Crohn's disease. Two digestive internal physician observed the ulcer characteristics of Crohn's disease under double balloon enteroscopy, and gave a simple endoscopic score for CD (SES-CD). We analyzed the correlation between SES-CD and Crohn's disease activity index (CDAI).
 Results: DBE indicated 24 patient ulcers (53.33%) locating at the end of the ileum, 5 (11.11%) locating at ileocolon, 16 (35.56%) locating at upper gatrointestinal tract and they did not affect the end of the ileum. Among them, 8 cases (17.78%) affected only jejunum. Thirty-two patients with longitudinal ulcers in Crohn's disease, accounting for 71.11%. There was no correlation between SES-CD score and CDAI score (r=0.237, P=0.136).
 Conclusion: The ulcerative appearance in Crohn's disease were diverse under double balloon enteroscopy. Crohn's disease could only affect the upper gastrointestinal tract or jejunum. The unwounded ileum and ileocecal valve couldn't be a sign to exclude Crohn's disease. CDAI score couldn't fully assess the prognosis of Crohn's disease.


Assuntos
Doença de Crohn/patologia , Enteroscopia de Duplo Balão , Doenças do Íleo/patologia , Doenças do Jejuno/patologia , Colo/patologia , Humanos , Estudos Prospectivos
19.
ISA Trans ; 76: 216-223, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29571582

RESUMO

This paper proposed the distributed moving horizon coordinated control scheme for the power balance and economic dispatch problems of micro-grid based on distributed generation. We design the power coordinated controller for each subsystem via moving horizon control by minimizing a suitable objective function. The objective function of distributed moving horizon coordinated controller is chosen based on the principle that wind power subsystem has the priority to generate electricity while photovoltaic power generation coordinates with wind power subsystem and the battery is only activated to meet the load demand when necessary. The simulation results illustrate that the proposed distributed moving horizon coordinated controller can allocate the output power of two generation subsystems reasonably under varying environment conditions, which not only can satisfy the load demand but also limit excessive fluctuations of output power to protect the power generation equipment.

20.
Mol Med Rep ; 16(6): 8223-8230, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28990090

RESUMO

Wear particles serve a central role in periprosthetic osteolysis, which leads to the aseptic loosening of prostheses. In the present study a lentiviral vector was constructed to silence macrophage colony stimulating factor (M­CSF) and receptor activator of nuclear factor κ­B ligand (RANKL) genes, which synergistically inhibit osteoclast formation and differentiation. To confirm the role of the calcineurin/nuclear factor of activated T cells (NFAT) pathway in osteolysis, we transduced murine macrophage/monocyte RAW264.7 cells with M­CSF­short hairpin (sh)RNA­RANKL­shRNA. Tumor necrosis factor­α (TNF­α) protein levels were evaluated using enzyme­linked immunosorbent assay. Transduced RAW264.7 cells were cultured in Transwell chambers in the presence of 0.1 mg/ml titanium particles to investigate the capacity of TNF­α inhibition to reduce wear debris­induced inflammation. RANKL, M­CSF, TNF­α, interleukin (IL)­1ß, IL­6 and NFATc1 mRNA levels were also assessed by reverse transcription­quantitative polymerase chain reaction. Osteoclastogenesis was measured by tartrate­resistant acid phosphatase (TRAP) mRNA quantification. Lentiviral­mediated double gene inhibition is known to be able to completely inhibit inflammatory osteolysis, simultaneously decreasing the number of NFATc1­ and TRAP­positive cells. The present study confirmed that the combined silencing of M­CSF and RANKL genes can inhibit the osteolysis induced by the wear particles around the prosthesis. The calcineurin/NFAT pathway serves a role in the prevention of prosthesis loosening.


Assuntos
Calcineurina/metabolismo , Inflamação/etiologia , Inflamação/metabolismo , Fator Estimulador de Colônias de Macrófagos/metabolismo , Fatores de Transcrição NFATC/metabolismo , Osteoclastos/metabolismo , Ligante RANK/metabolismo , Transdução de Sinais , Animais , Reabsorção Óssea/genética , Reabsorção Óssea/metabolismo , Reabsorção Óssea/patologia , Sobrevivência Celular/genética , Expressão Gênica , Inflamação/patologia , Mediadores da Inflamação/metabolismo , Fator Estimulador de Colônias de Macrófagos/genética , Camundongos , Ligante RANK/genética , Células RAW 264.7 , Titânio/efeitos adversos , Titânio/química
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