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1.
Medicine (Baltimore) ; 102(50): e36613, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-38115339

RESUMEN

Chronic kidney disease (CKD), a pervasive public health concern, can lead to complications like sarcopenia and reduced bone mineral density (BMD). However, it is still unclear exactly how muscle mass correlates with BMD in youngsters and adolescents with CKD. We aimed to investigate the association between appendicular skeletal muscle index (ASMI) and BMD among children and adolescents with CKD. In our research, we utilized data from the National Health and Nutrition Examination Survey (NHANES) collected between 2011 and 2014 to investigate the association of ASMI with BMD among this population. The association linking ASMI with total BMD was examined through multivariate linear regression models. Furthermore, fitted smoothing curves were employed, as well as generalized additive models. Our analysis finally included 503 CKD participants aged between 8 and 19 years. We found a significant association linking ASMI with total BMD among children and adolescents with CKD. The connection persisted even after accounting for covariates. Upon subgroup analysis, there was a statistically significant association of ASMI with total BMD for both males and females, as well as for Mexican-American and non-Hispanic White populations. However, no significant association was observed in other Hispanic, non-Hispanic Black, or populations of other races. We discovered a positive correlation linking the ASMI and the total BMD in children and teenagers with CKD. In CKD patients, maintaining skeletal muscle mass may be crucial for managing and preventing renal osteodystrophy.


Asunto(s)
Densidad Ósea , Insuficiencia Renal Crónica , Masculino , Femenino , Niño , Humanos , Adolescente , Adulto Joven , Adulto , Densidad Ósea/fisiología , Estudios Transversales , Encuestas Nutricionales , Músculo Esquelético/diagnóstico por imagen , Insuficiencia Renal Crónica/complicaciones
2.
Traffic ; 24(9): 384-396, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37341018

RESUMEN

Iron homeostasis is crucial for maintaining proper cellular function, and its disruption is considered one of the pathogenic mechanisms underlying musculoskeletal diseases. Under conditions of oxidative stress, the accumulation of cellular iron overload and lipid peroxidation can lead to ferroptosis. Extracellular vesicles (EVs), serving as mediators in the cell-to-cell communication, play an important role in regulating the outcome of cell ferroptosis. Growing evidence has proven that EV biogenesis and secretion are tightly associated with cellular iron export. Furthermore, different sources of EVs deliver diverse cargoes to bring about phenotypic changes in the recipient cells, either activating or inhibiting ferroptosis. Thus, delivering therapies targeting ferroptosis through EVs may hold significant potential for treating musculoskeletal diseases. This review aims to summarize current knowledge on the role of EVs in iron homeostasis and ferroptosis, as well as their therapeutic applications in musculoskeletal diseases, and thereby provide valuable insights for both research and clinical practice.


Asunto(s)
Vesículas Extracelulares , Ferroptosis , Enfermedades Musculoesqueléticas , Humanos , Hierro , Enfermedades Musculoesqueléticas/terapia , Homeostasis
3.
Front Bioeng Biotechnol ; 11: 1162263, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37362216

RESUMEN

Degenerative orthopedic diseases, as a global public health problem, have made serious negative impact on patients' quality of life and socio-economic burden. Traditional treatments, including chemical drugs and surgical treatments, have obvious side effects and unsatisfactory efficacy. Therefore, biological therapy has become the focus of researches on degenerative orthopedic diseases. Extracellular vesicles (EVs), with superior properties of immunoregulatory, growth support, and drug delivery capabilities, have emerged as a new cell-free strategy for the treatment of many diseases, including degenerative orthopedic diseases. An increasing number of studies have shown that EVs can be engineered through cargo loading, surface modification, and chemical synthesis to improve efficiency, specificity, and safety. Herein, a comprehensive overview of recent advances in engineering strategies and applications of engineered EVs as well as related researches in degenerative orthopedic diseases, including osteoarthritis (OA), osteoporosis (OP), intervertebral disc degeneration (IDD) and osteonecrosis of the femoral head (ONFH), is provided. In addition, we analyze the potential and challenges of applying engineered EVs to clinical practice.

4.
Curr Med Sci ; 43(3): 469-477, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37264195

RESUMEN

OBJECTIVE: The hypersensitivity of the kidney makes it susceptible to hypoxia injury. The involvement of neutrophil extracellular traps (NETs) in renal injury resulting from hypobaric hypoxia (HH) has not been reported. In this study, we aimed to investigate the expression of NETs in renal injury induced by HH and the possible underlying mechanism. METHODS: A total of 24 SD male rats were divided into three groups (n=8 each): normal control group, hypoxia group and hypoxia+pyrrolidine dithiocarbamate (PDTC) group. Rats in hypoxia group and hypoxia+PDTC group were placed in animal chambers with HH which was caused by simulating the altitude at 7000 meters (oxygen partial pressure about 6.9 kPa) for 7 days. PDTC was administered at a dose of 100 mg/kg intraperitoneally once daily for 7 days. Pathological changes of the rat renal tissues were observed under a light microscope; the levels of serum creatinine (SCr), blood urea nitrogen (BUN), cell-free DNA (cf-DNA) and reactive oxygen species (ROS) were measured; the expression levels of myeloperoxidase (MPO), citrullinated histone H3 (cit-H3), B-cell lymphoma 2 (Bcl-2), Bax, nuclear factor kappa B (NF-κB) p65 and phospho-NF-κB p65 (p-NF-κB p65) in rat renal tissues were detected by qRT-qPCR and Western blotting; the localization of NF-κB p65 expression in rat renal tissues was observed by immunofluorescence staining and the expression changes of NETs in rat renal tissues were detected by multiplex fluorescence immunohistochemical staining. RESULTS: After hypoxia, the expression of NF-κB protein in renal tissues was significantly increased, the levels of SCr, BUN, cf-DNA and ROS in serum were significantly increased, the formation of NETs in renal tissues was significantly increased, and a large number of tubular dilatation and lymphocyte infiltration were observed in renal tissues. When PDTC was used to inhibit NF-κB activation, NETs formation in renal tissue was significantly decreased, the expression level of Bcl-2 in renal tissues was significantly increased, the expression level of Bax was significantly decreased, and renal injury was significantly alleviated. CONCLUSION: HH induces the formation of NETs through the NF-κB signaling pathway, and it promotes apoptosis and aggravates renal injury by decreasing Bcl-2 and increasing Bax expression.


Asunto(s)
Trampas Extracelulares , FN-kappa B , Ratas , Masculino , Animales , FN-kappa B/metabolismo , Trampas Extracelulares/metabolismo , Especies Reactivas de Oxígeno , Proteína X Asociada a bcl-2/genética , Riñón/patología , Transducción de Señal , Hipoxia/patología , ADN
5.
PLoS One ; 18(2): e0281439, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36735737

RESUMEN

Acute kidney injury (AKI) is a serious and frequently observed disease associated with high morbidity and mortality. Weighted gene co-expression network analysis (WGCNA) is a research method that converts the relationship between tens of thousands of genes and phenotypes into the association between several gene sets and phenotypes. We screened potential target genes related to AKI through WGCNA to provide a reference for the diagnosis and treatment of AKI. Key biomolecules of AKI were investigated based on transcriptome analysis. RNA sequencing data from 39 kidney biopsy specimens of AKI patients and 9 normal subjects were downloaded from the GEO database. By WGCNA, the top 20% of mRNAs with the largest variance in the data matrix were used to construct a gene co-expression network with a p-value < 0.01 as a screening condition, showing that the blue module was most closely associated with AKI. Thirty-two candidate biomarker genes were screened according to the threshold values of |MM|≥0.86 and |GS|≥0.4, and PPI and enrichment analyses were performed. The top three genes with the most connected nodes, alanine-glyoxylate aminotransferase 2(AGXT2), serine hydroxymethyltransferase 1(SHMT1) and aconitase 2(ACO2), were selected as the central genes based on the PPI network. A rat AKI model was constructed, and the mRNA and protein expression levels of the central genes in the model and control groups were verified by PCR and immunohistochemistry experiments. The results showed that the relative mRNA expression and protein levels of AGXT2, SHMT1 and ACO2 showed a decrease in the model group. In conclusion, we inferred that there is a close association between AGXT2, SHMT1 and ACO2 genes and the development of AKI, and the down-regulation of their expression levels may induce AKI.


Asunto(s)
Lesión Renal Aguda , Glicina Hidroximetiltransferasa , Animales , Ratas , Lesión Renal Aguda/diagnóstico , Lesión Renal Aguda/genética , Lesión Renal Aguda/metabolismo , Biomarcadores , Perfilación de la Expresión Génica/métodos , Redes Reguladoras de Genes , Glicina Hidroximetiltransferasa/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo , Aconitato Hidratasa/metabolismo
6.
Ren Fail ; 44(1): 2056-2065, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36420656

RESUMEN

BACKGROUND: In recent years, peroxisome proliferator-activated receptor γ (PPARγ) has been found to be closely associated with hypoxia renal disease. The aim of this study was to investigate the relationship between rosiglitazone and mitochondrial apoptosis in renal tissue and its associated mechanisms. METHODS: Twenty-four male Sprague-Dawley rats were randomly divided into three groups (n = 8 in each): normal control group, hypoxia injury group (equal volume of 0.9% saline), and PPARγ agonist group (Rosiglitazone, 10 mg/kg · d, intraperitoneally). The hypoxia injury group and PPARγ agonist group were placed in a hypoxia chamber and the simulated altitude was set at 7,000 m for 7 days. Blood and kidney samples were collected after 7 days. The quantitative real-time polymerase chain reaction and Western blot methods were used to determine the expression of PPARγ, nuclear factor kappa-B (NF-κB), B-cell lymphoma-2 (Bcl-2), and Bax. RESULTS: The results showed that compared with the normal control group, the renal tissue of rats after hypoxia was severely damaged, as shown by massive renal tubular epithelial cell degeneration and detachment, and renal tubular dilation. The NF-κB protein expression significantly increased, the Bcl-2 protein and mRNA expression significantly decreased, and Bax protein and mRNA expression significantly increased (p < .05 for all). Renal injury was much less severe in the PPARγ agonist group compared to the hypoxia injury group. CONCLUSIONS: Rosiglitazone can alleviate hypoxia renal injury, with the possible mechanism involving attenuation of apoptosis by inhibiting the activation of the NF-κB signaling pathway in a PPARγ-dependent manner and increasing Bcl-2 and decreasing Bax expression.


Asunto(s)
PPAR gamma , Tiazolidinedionas , Masculino , Ratas , Animales , Rosiglitazona/farmacología , PPAR gamma/metabolismo , FN-kappa B/metabolismo , Proteína X Asociada a bcl-2/metabolismo , Tiazolidinedionas/farmacología , Tiazolidinedionas/metabolismo , Ratas Sprague-Dawley , Transducción de Señal , Apoptosis , Células Epiteliales/metabolismo , Hipoxia/complicaciones , Hipoxia/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Hipoglucemiantes , Riñón/metabolismo , ARN Mensajero/metabolismo
7.
Sensors (Basel) ; 22(18)2022 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-36146324

RESUMEN

Simultaneous localization and mapping (SLAM) is a core technology for mobile robots working in unknown environments. Most existing SLAM techniques can achieve good localization accuracy in static scenes, as they are designed based on the assumption that unknown scenes are rigid. However, real-world environments are dynamic, resulting in poor performance of SLAM algorithms. Thus, to optimize the performance of SLAM techniques, we propose a new parallel processing system, named SOLO-SLAM, based on the existing ORB-SLAM3 algorithm. By improving the semantic threads and designing a new dynamic point filtering strategy, SOLO-SLAM completes the tasks of semantic and SLAM threads in parallel, thereby effectively improving the real-time performance of SLAM systems. Additionally, we further enhance the filtering effect for dynamic points using a combination of regional dynamic degree and geometric constraints. The designed system adds a new semantic constraint based on semantic attributes of map points, which solves, to some extent, the problem of fewer optimization constraints caused by dynamic information filtering. Using the publicly available TUM dataset, SOLO-SLAM is compared with other state-of-the-art schemes. Our algorithm outperforms ORB-SLAM3 in accuracy (maximum improvement is 97.16%) and achieves better results than Dyna-SLAM with respect to time efficiency (maximum improvement is 90.07%).


Asunto(s)
Robótica , Algoritmos , Robótica/métodos , Semántica
8.
Materials (Basel) ; 15(15)2022 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-35897621

RESUMEN

Sm3+ and Ce3+ singly doped and Sm3+ and Ce3+ co-doped Sr3B2O6 phosphors are prepared via a high-temperature solid-state reaction method. The crystal structure and phase purity are characterized by X-ray diffraction (XRD) analyses. The Sm3+-doped sample displays an emission in the orange-red region, with the strongest emission line at about 648 nm and possessing a good luminescence thermal stability between 78 and 500 K. With the increase in the Sm3+ content, the concentration quenching is observed due to the cross-relaxation (CR) processes among the Sm3+ ions. Upon 340 nm excitation, the Ce3+-doped phosphor presents a broad emission band in the blue region with a maximum at about 420 nm, which overlaps well with the 6H5/2 → 6P3/2 excitation line of Sm3+ and implies the possible energy transfer from Ce3+ to Sm3+. The spectral and decay measurements of the Ce3+ and Sm3+ co-doped samples are conducted and the Inokuti-Hirayama (I-H) model is adopted to analyze the luminescence decay dynamics of the donor Ce3+. Owing to the evident sensitization of the Sm3+ by the Ce3+ ions, the co-doped samples exhibit color variation under different wavelength excitations, endowing them with potential applications in optical anti-counterfeiting.

9.
Diagnostics (Basel) ; 11(3)2021 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-33809048

RESUMEN

Segmentation of skin lesions is a challenging task because of the wide range of skin lesion shapes, sizes, colors, and texture types. In the past few years, deep learning networks such as U-Net have been successfully applied to medical image segmentation and exhibited faster and more accurate performance. In this paper, we propose an extended version of U-Net for the segmentation of skin lesions using the concept of the triple attention mechanism. We first selected regions using attention coefficients computed by the attention gate and contextual information. Second, a dual attention decoding module consisting of spatial attention and channel attention was used to capture the spatial correlation between features and improve segmentation performance. The combination of the three attentional mechanisms helped the network to focus on a more relevant field of view of the target. The proposed model was evaluated using three datasets, ISIC-2016, ISIC-2017, and PH2. The experimental results demonstrated the effectiveness of our method with strong robustness to the presence of irregular borders, lesion and skin smooth transitions, noise, and artifacts.

10.
Adv Mater ; 32(37): e2003012, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32761715

RESUMEN

The lithium-sulfur (Li-S) battery is regarded as a promising high-energy-density battery system, in which the dissolution-precipitation redox reactions of the S cathode are critical. However, soluble Li polysulfides (LiPSs), as the indispensable intermediates, easily diffuse to the Li anode and react with the Li metal severely, thus depleting the active materials and inducing the rapid failure of the battery, especially under practical conditions. Herein, an organosulfur-containing solid electrolyte interphase (SEI) is tailored for the stabilizaiton of the Li anode in Li-S batteries by employing 3,5-bis(trifluoromethyl)thiophenol as an electrolyte additive. The organosulfur-containing SEI protects the Li anode from the detrimental reactions with LiPSs and decreases its corrosion. Under practical conditions with a high-loading S cathode (4.5 mgS cm-2 ), a low electrolyte/S ratio (5.0 µL mgS -1 ), and an ultrathin Li anode (50 µm), a Li-S battery delivers 82 cycles with an organosulfur-containing SEI in comparison to 42 cycles with a routine SEI. This work provokes the vital insights into the role of the organic components of SEI in the protection of the Li anode in practical Li-S batteries.

11.
Zhongguo Zhen Jiu ; 40(3): 247-50, 2020 Mar 12.
Artículo en Chino | MEDLINE | ID: mdl-32270635

RESUMEN

OBJECTIVE: To compare the clinical effect between Stiletto needle combined with massotherapy and articular injection of sodium hyaluronate for pain in patients with knee osteoarthritis (KOA). METHODS: A total of 156 patients with KOA were randomly divided into an observation group and a control group, 78 cases in each group. The patients in the observation group were treated with Stiletto needle (once a week) combined with massotherapy (twice a week); the patients in the control group were treated with articular injection of sodium hyaluronate (once a week). The treatment period were 5 weeks in total. The visual analogue scale (VAS) score, local tenderness value, knee joint activity and Lysholm knee joint score were recorded before treatment, 3 weeks and 5 weeks of treatment. RESULTS: Compared before treatment, the VAS score, local tenderness value, knee joint activity and Lysholm knee joint score in the two groups were improved 5 weeks of treatment (P<0.05). After 5 weeks of treatment, The local tenderness value and Lysholm knee joint score in the observation group were significantly improved compared with the control group (P<0.05), but the knee joint activity in the control group was superior to that in the observation group (P<0.05). CONCLUSION: The Stiletto needle combined with massotherapy are superior to articular injection of sodium hyaluronate in relieving pain and improving knee joint function in patients with early-to-moderate KOA, but its effect on joint activity is inferior to sodium hyaluronate.


Asunto(s)
Terapia por Acupuntura , Masaje , Osteoartritis de la Rodilla/terapia , Manejo del Dolor , Humanos , Articulación de la Rodilla/fisiopatología , Dolor , Dimensión del Dolor , Resultado del Tratamiento
12.
J Cell Physiol ; 235(5): 4268-4278, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-31608996

RESUMEN

The relationship between age and breast cancer is ambiguous. Here, we analyzed the differential expression pattern of long noncoding RNAs (lncRNAs) and messenger RNAs (mRNAs) in different age groups to provide an effective association between age and breast cancer risk at the molecular level. We integrated the microarray information from the Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) data sets. The patients were divided into young ( < 50 years) and old ( ≥ 50 years) age groups and evaluated by differential gene expression, weighted gene correlation network analysis (WGCNA), functional enrichment analyses, and coexpression analysis. To determine their potential clinical significance, univariate Cox regression analysis and survival assessment were conducted. We identified two lncRNAs (AL139280.1 and AP000851.1) and three mRNAs (MT1M, HBB, and TFPI2) as the risk markers, and Gene set enrichment analysis (GSEA) focusing on a single gene revealed that "pyrimidine metabolism," "cell cycle," and "P53 signaling pathway" were coenriched. These data demonstrated that age may be a risk factor for breast carcinogenesis and prognosis and provide an in-depth molecular characterization based on the expression patterns of lncRNAs and mRNAs.


Asunto(s)
Envejecimiento , Biomarcadores de Tumor/metabolismo , Neoplasias de la Mama/metabolismo , Regulación Neoplásica de la Expresión Génica/fisiología , Neoplasias de la Mama/genética , Femenino , Humanos , ARN Largo no Codificante , ARN Mensajero/genética , ARN Mensajero/metabolismo , Factores de Riesgo
13.
Angew Chem Int Ed Engl ; 59(31): 12636-12652, 2020 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-31490599

RESUMEN

The development of energy-storage devices has received increasing attention as a transformative technology to realize a low-carbon economy and sustainable energy supply. Lithium-sulfur (Li-S) batteries are considered to be one of the most promising next-generation energy-storage devices due to their ultrahigh energy density. Despite the extraordinary progress in the last few years, the actual energy density of Li-S batteries is still far from satisfactory to meet the demand for practical applications. Considering the sulfur electrochemistry is highly dependent on solid-liquid-solid multi-phase conversion, the electrolyte amount plays a primary role in the practical performances of Li-S cells. Therefore, a lean electrolyte volume with low electrolyte/sulfur ratio is essential for practical Li-S batteries, yet under these conditions it is highly challenging to achieve acceptable electrochemical performances regarding sulfur kinetics, discharge capacity, Coulombic efficiency, and cycling stability especially for high-sulfur-loading cathodes. In this Review, the impact of the electrolyte/sulfur ratio on the actual energy density and the economic cost of Li-S batteries is addressed. Challenges and recent progress are presented in terms of the sulfur electrochemical processes: the dissolution-precipitation conversion and the solid-solid multi-phasic transition. Finally, prospects of future lean-electrolyte Li-S battery design and engineering are discussed.

14.
Dalton Trans ; 48(46): 17331-17339, 2019 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-31724671

RESUMEN

Using two Schiff-base ligands containing an electron-withdrawing group (NO2), we obtained two mononuclear and two trinuclear complexes with the general formula [Dy(hni)(NO3)(DMF)2]·DMF (1·DMF), [Dy(hni)2(H2O)2]·NO3·EtOH (2·NO3·EtOH), [Dy3(hnc)3(DMF)6] (3) and [Gd3(hnc)3(DMF)6] (4) (H-hni: 2-(hydroxyl-3-methoxy-5-nitrophenyl)methylene(isonictino)hydrazine and H3-hnc: 1,5-bis(2-hydroxy-3-methoxy-5-nitrobenzylidene)carbonohydrazide). Four complexes were confirmed by infrared spectroscopy and single-crystal X-ray diffraction. The crystal structure of complex 3 reveals that the modified Schiff-base ligand provides two different tridentate coordination pockets (ONN and ONO) to encapsulate DyIII with a unique N-N pathway. The magnetic properties of all four complexes have been investigated using dc and ac susceptibility measurements. The frequency-dependent ac susceptibility is indicative of single-molecule magnetic behavior without and/or with an optimum dc field with a relaxation barrier Ueff = 34 K (400 Oe), 19 K (0 Oe) and 80 K (0 Oe) for complexes 1, 2 and 3, respectively.

15.
J Cell Mol Med ; 23(12): 8410-8419, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31613058

RESUMEN

Long non-coding RNAs (lncRNAs), which competitively bind miRNAs to regulate target mRNA expression in the competing endogenous RNAs (ceRNAs) network, have attracted increasing attention in breast cancer research. We aim to find more effective therapeutic targets and prognostic markers for breast cancer. LncRNA, mRNA and miRNA expression profiles of breast cancer were downloaded from TCGA database. We screened the top 5000 lncRNAs, top 5000 mRNAs and all miRNAs to perform weighted gene co-expression network analysis. The correlation between modules and clinical information of breast cancer was identified by Pearson's correlation coefficient. Based on the most relevant modules, we constructed a ceRNA network of breast cancer. Additionally, the standard Kaplan-Meier univariate curve analysis was adopted to identify the prognosis of lncRNAs. Ultimately, a total of 23 and 5 modules were generated in the lncRNAs/mRNAs and miRNAs co-expression network, respectively. According to the Green module of lncRNAs/mRNAs and Blue module of miRNAs, our constructed ceRNA network consisted of 52 lncRNAs, 17miRNAs and 79 mRNAs. Through survival analysis, 5 lncRNAs (AL117190.1, COL4A2-AS1, LINC00184, MEG3 and MIR22HG) were identified as crucial prognostic factors for patients with breast cancer. Taken together, we have identified five novel lncRNAs related to prognosis of breast cancer. Our study has contributed to the deeper understanding of the molecular mechanism of breast cancer and provided novel insights into the use of breast cancer drugs and prognosis.


Asunto(s)
Biomarcadores de Tumor/genética , Perfilación de la Expresión Génica/métodos , Regulación Neoplásica de la Expresión Génica , MicroARNs/genética , ARN Largo no Codificante/genética , ARN Mensajero/genética , Femenino , Redes Reguladoras de Genes , Humanos , Estimación de Kaplan-Meier , Pronóstico
16.
Sensors (Basel) ; 19(19)2019 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-31546666

RESUMEN

With the development of wireless communication technology, cognitive radio needs to solve the spectrum sensing problem of wideband wireless signals. Due to performance limitation of electronic components, it is difficult to complete spectrum sensing of wideband wireless signals at once. Therefore, it is required that the wideband wireless signal has to be split into a set of sub-bands before the further signal processing. However, the sequence of sub-band perception has become one of the important factors, which deeply-impact wideband spectrum sensing performance. In this paper, we develop a novel approach for sub-band selection through the non-stationary multi-arm bandit (NS-MAB) model. This approach is based on a well-known order optimal policy for NS-MAB mode called discounted upper confidence bound (D-UCB) policy. In this paper, according to different application requirements, various discount functions and exploration bonuses of D-UCB are designed, which are taken as the parameters of the policy proposed in this paper. Our simulation result demonstrates that the proposed policy can provide lower cumulative regret than other existing state-of-the-art policies for sub-band selection of wideband spectrum sensing.

17.
Sensors (Basel) ; 19(9)2019 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-31083381

RESUMEN

The cognitive wireless sensor network (CWSN) is an important development direction of wireless sensor networks (WSNs), and spectrum sensing technology is an essential prerequisite for CWSN to achieve spectrum sharing. However, the existing non-cooperative narrowband spectrum sensing technology has difficulty meeting the application requirements of CWSN at present. In this paper, we present a non-cooperative spectrum sensing algorithm for CWSN, which combines the multi-resolution technique, phase space reconstruction method, and singular spectrum entropy method to sense the spectrum of narrowband wireless signals. Simulation results validate that this algorithm can greatly improve the detection probability at a low signal-to-noise ratio (SNR) (from -19dB to -12dB), and the detector can quickly achieve the best detection performance as the SNR increases. This algorithm could promote the development of CWSN and the application of WSNs.

18.
Angew Chem Int Ed Engl ; 58(12): 3779-3783, 2019 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-30548388

RESUMEN

Surface reactions constitute the foundation of various energy conversion/storage technologies, such as the lithium-sulfur (Li-S) batteries. To expedite surface reactions for high-rate battery applications demands in-depth understanding of reaction kinetics and rational catalyst design. Now an in situ extrinsic-metal etching strategy is used to activate an inert monometal nitride of hexagonal Ni3 N through iron-incorporated cubic Ni3 FeN. In situ etched Ni3 FeN regulates polysulfide-involving surface reactions at high rates. Electron microscopy was used to unveil the mechanism of in situ catalyst transformation. The Li-S batteries modified with Ni3 FeN exhibited superb rate capability, remarkable cycling stability at a high sulfur loading of 4.8 mg cm-2 , and lean-electrolyte operability. This work opens up the exploration of multimetallic alloys and compounds as kinetic regulators for high-rate Li-S batteries and also elucidates catalytic surface reactions and the role of defect chemistry.

19.
Mol Med Rep ; 19(1): 362-374, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30431072

RESUMEN

Chronic lymphocytic leukemia (CLL) is a malignant clonal proliferative disorder of B cells. Inhibition of cell apoptosis and cell cycle arrest are the main pathological causes of this disease, but its molecular mechanism requires further investigation. The purpose of the present study was to identify biomarkers for the early diagnosis and treatment of CLL, and to explore the molecular mechanisms of CLL progression. A total of 488 differentially expressed genes (DEGs) and 32 differentially expressed microRNAs (miRNAs; DEMs) for CLL were identified by analyzing the gene chips GSE22529, GSE39411 and GSE62137. Functional and pathway enrichment analyses of DEGs demonstrated that DEGs were mainly involved in transcriptional dysregulation and multiple signaling pathways, such as the nuclear factor­κB and mitogen­activated protein kinase signaling pathways. In addition, Cytoscape software was used to visualize the protein­protein interactions of these DEGs in order to identify hub genes, which could be used as biomarkers for the early diagnosis and treatment of CLL. Cytoscape software was also used to analyze the association between the predicted target mRNAs of DEMs and DEGs and increase knowledge about the miRNA­mRNA regulatory network associated with the progression of CLL. Taken together, the present study provided a bioinformatics basis for advancing our understanding of the pathogenesis of CLL by identifying differentially expressed hub genes, miRNA­mRNA target pairs and molecular pathways. In addition, hub genes may be used as novel biomarkers for the diagnosis of CLL and to guide the selection of CLL drug combinations.


Asunto(s)
Biomarcadores de Tumor/genética , Biología Computacional/métodos , Regulación Neoplásica de la Expresión Génica , Redes Reguladoras de Genes , Leucemia Linfocítica Crónica de Células B/genética , MicroARNs/genética , ARN Mensajero/genética , Biomarcadores de Tumor/metabolismo , Perfilación de la Expresión Génica , Ontología de Genes , Humanos , Leucemia Linfocítica Crónica de Células B/metabolismo , Mapas de Interacción de Proteínas , Transcriptoma
20.
Front Plant Sci ; 9: 1020, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30061912

RESUMEN

Our previous studies showed that hydrogen-rich water (HRW) promoted the biosynthesis of anthocyanin under UV-A in radish. However, molecular mechanism involved in the regulation of the anthocyanin biosynthesis is still unclear. In this study, the role of calcium (Ca2+) in HRW-promoted anthocyanin biosynthesis in radish sprouts hypocotyls under UV-A was investigated. The results showed that a positive effect of HRW on the content of cytosolic calcium and anthocyanin accumulation, mimicking the effects of induced CaCl2. Exogenous addition of Ca2+ chelator bis (ß-aminoethylether)-N,N,N',N'-tetraacetic acid (EGTA) and inositol 1,4,5-trisphosphate (IP3) synthesis inhibitor neomycin partially reversed the facilitated effect of HRW. The positive effects of HRW on activity of anthocyanin biosynthetic-enzymes (L-phenylalanine ammonia-lyase, PAL; chalcone isomerase, CHI; dihydroflavonol 4-reductase, DFR and UDP glc-flavonoid 3-O-glucosyl transferase, UFGT) were reversed by EGTA and neomycin. Further tests confirmed that the upregulation of anthocyanin biosynthetic related genes induced by HRW was substantially inhibited by calcium antagonists. The possible involvement of CaM in HRW-regulated anthocyanin biosynthesis was also preliminarily investigated in this study. Taken together, our results indicate that IP3-dependent calcium signaling pathway might be involved in HRW-regulated anthocyanin biosynthesis under UV-A irradiation.

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