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1.
J Colloid Interface Sci ; 596: 278-287, 2021 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-33848743

RESUMO

Tubular In2O3@SnIn4S8 hierarchical hybrid photocatalyst was firstly fabricated by a two-step method. The morphology and composition were characterized by scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD). The XRD results show that the obtained In2O3 microtubes were highly crystallized, while the SnIn4S8 flakes prepared at low temperature were poorly crystallized. The SEM image of the hybrid shows that numerous SnIn4S8 nanoflakes were assembled over the surface of In2O3 microtubes. In2O3 served as dispersing-templates have reduced the agglomeration of SnIn4S8 flakes. Meanwhile, the heterojunctions formed at the interfaces between In2O3 and SnIn4S8 could facilitate the interfacial charge transfer, as well as promote the photocatalytic activity of the hybrid. In the treatment of Cr(VI)-containing wastewater, the In2O3@SnIn4S8 hybrid not only exhibited strong adsorption ability, but also showed remarkably enhanced photocatalytic activity compared with pure SnIn4S8. The photocatalytic reaction constant k for In2O3@SnIn4S8 was approximately 2.54 times higher than that of SnIn4S8. The efficient activity of this hybrid photocatalyst should be ascribed to the promoted separation efficiency of electron/hole pairs, which was proved by the following three-dimensional excitation-emission matrix fluorescence spectra (3D EEMs), photocurrent responds, and EIS characterizations.

2.
Sensors (Basel) ; 21(6)2021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-33801861

RESUMO

Underwater fishing nets represent a danger faced by autonomous underwater vehicles (AUVs). To avoid irreparable damage to the AUV caused by fishing nets, the AUV needs to be able to identify and locate them autonomously and avoid them in advance. Whether the AUV can avoid fishing nets successfully depends on the accuracy and efficiency of detection. In this paper, we propose an object detection multiple receptive field network (MRF-Net), which is used to recognize and locate fishing nets using forward-looking sonar (FLS) images. The proposed architecture is a center-point-based detector, which uses a novel encoder-decoder structure to extract features and predict the center points and bounding box size. In addition, to reduce the interference of reverberation and speckle noises in the FLS image, we used a series of preprocessing operations to reduce the noises. We trained and tested the network with data collected in the sea using a Gemini 720i multi-beam forward-looking sonar and compared it with state-of-the-art networks for object detection. In order to further prove that our detector can be applied to the actual detection task, we also carried out the experiment of detecting and avoiding fishing nets in real-time in the sea with the embedded single board computer (SBC) module and the NVIDIA Jetson AGX Xavier embedded system of the AUV platform in our lab. The experimental results show that in terms of computational complexity, inference time, and prediction accuracy, MRF-Net is better than state-of-the-art networks. In addition, our fishing net avoidance experiment results indicate that the detection results of MRF-Net can support the accurate operation of the later obstacle avoidance algorithm.

3.
Biomed Pharmacother ; 137: 111308, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33556877

RESUMO

BACKGROUND AND OBJECTIVE: Doxorubicin (DOX) is an anthracycline antitumor antibiotic widely utilized in treating various tumors. Nevertheless, the toxicity of DOX toward normal cells limits its applicability, with nephrotoxicity considered a major dose-limiting adverse effect. Apigenin (APG), a flavonoid widely distributed in natural plants, has been reported to have antioxidant, anti-inflammatory, and mild tumor-suppressive properties. In this study, we investigated the role of APG in DOX-induced nephrotoxicity and chemotherapeutic efficacy. METHODS: Male BALB/c mice were administered DOX (11.5 mg/kg) via the tail vein to establish the DOX nephropathy model. After treatment with or without APG (125, 250, and 500 mg/kg) for two weeks, urine, serum, and tissue samples were collected to evaluate proteinuria, serum albumin, serum creatinine (Scr), blood urea nitrogen (BUN), superoxide dismutase (SOD) activity, malondialdehyde (MDA), glutathione (GSH), and pathological changes. Rat renal tubular epithelial cells (NRK52E), murine podocyte cells (MPC5), and murine breast cancer cells (4T1) were utilized to verify the effect of APG on DOX-induced cell injury. An MTT assay was employed to analyze cell viability. Apoptosis was evaluated using a colorimetric TUNEL staining and cleaved caspase-3 protein analysis by western blotting. A reactive oxygen species (ROS)/superoxide (O2-) fluorescence probe was employed to determine oxidative injury. Western blotting was used to analyze nephrin, α-smooth muscle actin (α-SMA), collagen I (Col1), fibronectin (FN), and SOD2 expression. The mRNA levels of tumor necrosis factor-α (TNF-α), interleukin-18 (IL-18), IL-6, NACHT, LRR, PYD domain-containing protein 3 (NLRP3), caspase-1, and IL-1ß were tested by reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: APG ameliorated DOX-elicited renal injuries in both the glomeruli and tubules. The DOX + APG groups had much lower tissue MDA, IL-6, TNF-α, NLRP3, caspase-1, and IL-1ß levels and generation of intracellular ROS, but significantly higher SOD activity and GSH levels compared to those of the DOX group. Additionally, APG attenuated DOX-induced morphological changes, loss of cellular viability, and apoptosis in NRK-52E and MPC-5 cells, but not in 4T1 cells. CONCLUSION: APG has a protective role against DOX-induced nephrotoxicity, without weakening DOX cytotoxicity in malignant tumors. Thus, APG may serve as a potential protective agent against renal injury and inflammatory diseases and may be a promising candidate to attenuate renal toxicity in cancer patients treated with DOX.

4.
Nucleic Acids Res ; 49(5): 2859-2877, 2021 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-33577677

RESUMO

N 6-Methyladenosine (m6A) is the most abundant modification within diverse RNAs including mRNAs and lncRNAs and is regulated by a reversible process with important biological functions. Human YTH domain family 2 (YTHDF2) selectively recognized m6A-RNAs to regulate degradation. However, the possible regulation of YTHDF2 by protein post-translational modification remains unknown. Here, we show that YTHDF2 is SUMOylated in vivo and in vitro at the major site of K571, which can be induced by hypoxia while reduced by oxidative stress and SUMOylation inhibitors. SUMOylation of YTHDF2 has little impact on its ubiquitination and localization, but significantly increases its binding affinity of m6A-modified mRNAs and subsequently results in deregulated gene expressions which accounts for cancer progression. Moreover, Disease-free survival analysis of patients with lung adenocarcinoma derived from TCGA dataset reveals that higher expression of YTHDF2 together with higher expression of SUMO1 predicts poor prognosis. Our works uncover a new regulatory mechanism for YTHDF2 recognition of m6A-RNAs and highlight the importance of YTHDF2 SUMOylation in post-transcriptional gene expression regulation and cancer progression.


Assuntos
Adenosina/análogos & derivados , Neoplasias/metabolismo , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/metabolismo , Sumoilação , Adenosina/metabolismo , Animais , Hipóxia Celular , Linhagem Celular , Progressão da Doença , Humanos , Lisina/metabolismo , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias/genética , Neoplasias/patologia , Estresse Oxidativo , Estabilidade de RNA , RNA Mensageiro/química , Proteínas de Ligação a RNA/química , Proteínas Modificadoras Pequenas Relacionadas à Ubiquitina/antagonistas & inibidores , Transcriptoma , Ubiquitinação
5.
Nanoscale ; 2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33481982

RESUMO

Topological Weyl semimetals have attracted considerable interest because they manifest underlying physics and device potential in spintronics. Large anomalous Hall effect (AHE) in non-collinear antiferromagnets (AFMs) represents a striking Weyl phase, which is associated with Bloch-band topological features. In this work, we report robust AHE and Lifshitz transition in high-quality Weyl semimetal Mn3Ge thin film, comprising stacked Kagome lattice and chiral antiferromagnetism. We successfully achieved giant AHE in our Mn3Ge film, with a strong Berry curvature enhanced by the Weyl phase. The enormous coercive field HC in our AHE curve at 5 K reached an unprecedented 5.3 T among hexagonal Mn3X systems. Our results provide direct experimental evidence of an electronic topological transition in the chiral AFMs. The temperature was demonstrated to play an efficient role in tuning the carrier concentration, which could be quantitatively determined by the two-band model. The electronic band structure crosses the Fermi energy level and leads to the reversal of carrier type around 50 K. The results not only offer new functionality for effectively modulating the Fermi level location in topological Weyl semimetals but also present a promising route of manipulating the carrier concentration in antiferromagnetic spintronic devices.

6.
J Microbiol Biotechnol ; 31(1): 1-7, 2021 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-33323672

RESUMO

Bacterial biofilm is a community of bacteria that are embedded and structured in a self-secreted extracellular matrix. An important clinical-related characteristic of bacterial biofilms is that they are much more resistant to antimicrobial agents than the planktonic cells (up to 1,000 times), which is one of the main causes of antibiotic resistance in clinics. Therefore, infections caused by biofilms are notoriously difficult to eradicate, such as lung infection caused by Pseudomonas aeruginosa in cystic fibrosis patients. Understanding the resistance mechanisms of biofilms will provide direct insights into how we overcome such resistance. In this review, we summarize the characteristics of biofilms and chronic infections associated with bacterial biofilms. We examine the current understanding and research progress on the major mechanisms of antibiotic resistance in biofilms, including quorum sensing. We also discuss the potential strategies that may overcome biofilm-related antibiotic resistance, focusing on targeting biofilm EPSs, blocking quorum sensing signaling, and using recombinant phages.

7.
Environ Pollut ; 271: 116327, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33360654

RESUMO

Fine particulate matter (PM2.5) has attracted extensive attention because of its baneful influence on human health and the environment. However, the sparse distribution of PM2.5 measuring stations limits its application to public utility and scientific research, which can be remedied by satellite observations. Therefore, we developed a Geo-intelligent long short-term network (Geoi-LSTM) to estimate hourly ground-level PM2.5 concentrations in 2017 in Wuhan Urban Agglomeration (WUA). We conducted contrast experiments to verify the effectiveness of our model and explored the optimal modeling strategy. It turned out that Geoi-LSTM with TOA reflectance, meteorological conditions, and NDVI as inputs performs best. The station-based cross-validation R2, root mean squared error and mean absolute error are 0.82, 15.44 µg/m3, 10.63 µg/m3, respectively. Based on model results, we revealed spatiotemporal characteristics of PM2.5 in WUA. Generally speaking, during the day, PM2.5 concentration remained stable at a relatively high level in the morning and decreased continuously in the afternoon. While during the year, PM2.5 concentrations were highest in winter, lowest in summer, and in-between in spring and autumn. Combined with meteorological conditions, we further analyzed the whole process of a PM2.5 pollution event. Finally, we discussed the loss in removing clouds-covered pixels and compared our model with several popular models. Overall, our results can reflect hourly PM2.5 concentrations seamlessly and accurately with a spatial resolution of 5 km, which benefits PM2.5 exposure evaluations and policy regulations.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Aerossóis/análise , Poluentes Atmosféricos/análise , Poluição do Ar/análise , China , Monitoramento Ambiental , Humanos , Memória de Curto Prazo , Material Particulado/análise
8.
Dalton Trans ; 2020 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-33295909

RESUMO

The anion-adaptive self-assembly described here not only offers a facile approach to produce large single-molecule magnets without the need for precise manipulation of the stoichiometry of ligand-metal centers but also provides an understanding of how structural factors affect the magnetic properties. X-ray diffraction analysis reveals that a rare hexagonal metallacycle with a diameter approaching 23 Å was obtained. Magnetic investigation shows that the resulting hexagonal metallacycle behaves as a typical single-molecule magnet with double relaxation under dc field thanks to the different coordination geometry of the DyIII centers.

9.
Sci Rep ; 10(1): 21216, 2020 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-33277561

RESUMO

User-friendly phenotypic antibiotic susceptibility testing (AST) methods are urgently needed in many fields including clinical medicine, epidemiological studies and drug research. Herein, we report a convenient and cost-effective phenotypic AST method based on online monitoring bacterial growth with a developed 8-channel contactless conductometric sensor (CCS). Using E. coli and V. parahaemolyticus as microorganism models, as well as enoxacin, florfenicol, ampicillin, kanamycin and sulfadiazine as antibiotic probes. The minimum inhibitory concentration (MIC) determination was validated in comparison with standard broth microdilution (BMD) assay. The total essential agreements between the CCS AST assays and the reference BMD AST assays are 68.8-92.3%. The CCS has an approximate price of $9,000 (USD). Requiring neither chemical nor biotic auxiliary materials for the assay makes the cost of each sample < $1. The MICs obtained with the automated CCS AST assays are more precise than those obtained with the manual BMD. Moreover, in 72 percent of the counterpart, the MICs obtained with the CCS AST assays are higher than that obtained with the BMD AST assays. The proposed CCS AST method has advantages in affordability, accuracy, sensitivity and user-friendliness.

10.
Acta Biomater ; 2020 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-33249226

RESUMO

Silk is a naturally occurring biopolymer formed into fibers composed primarily of fibroin and sericin proteins. The outstanding mechanical properties of silk fibroin (SF) provides numerous applications for silk-based biomaterials. However, the canonical approaches for fabricating silk-based biomaterials typically involve degumming to remove the silk sericin (SS) to avoid adverse biological effects. Meanwhile, sericin has multiple biological functions including outstanding hydrophilicity, promoting cell attachment that are useful to exploit in new materials, inspiring the use of sericin-based biomaterials for biomedical applications. However, compared to fibroin, sericin is not a structural protein, thus sericin-based materials do not provide robust mechanical properties. To address this problem, we report an effective method for fabricating silk fibroin-sericin protein (SS-SF) composites directly from whole cocoons, negating the traditional extraction step to remove the sericin. This approach combines the material features from both fibroin as a structural unit and sericin as a biological functional unit, to achieve advantages regarding processing and materials properties, not only simplifying processing and maintaining the mechanical properties of the fibroin by avoiding degumming, but also endowing these SS-SF composite materials with enhanced hydrophilicity and cell adhesion performance to promote cell growth and proliferation. In addition, these protein composites could be fabricated into a variety of materials formats (e.g. films, sponges, monoliths) to fit different biomedical applications.

11.
Chem Commun (Camb) ; 2020 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-33220663

RESUMO

We report the cyclic single-crystal-to-single-crystal transformation of three hydrogen-bonded organic frameworks (HOFs), induced by the change of temperature and humidity, which clearly reveals that the -SO3-and -NH2 groups in UPC-H7 and UPC-H8 facilitate the diffusion of water molecules into their anhydrous structures to form hydrous UPC-H9. Their proton conductivity was studied under different humidity at varying temperature, showing that the proton conductivity is closely related to water molecules entering the crystal structures arising from the hydrogen bonded reorganization in combination with the triaxial single-crystal proton conductivity tests.

12.
Appl Opt ; 59(32): 10049-10060, 2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-33175779

RESUMO

Imaging through the wavy air-water surface suffers from severe geometric distortions, which are caused by the light refraction effect that affects the normal operations of underwater exploration equipment such as the autonomous underwater vehicle (AUV). In this paper, we propose a deep learning-based framework, namely the self-attention generative adversarial network (SAGAN), to remove the geometric distortions and restore the distorted image captured through the water-air surface. First, a K-means-based image pre-selection method is employed to acquire a less distorted image that preserves much useful information from an image sequence. Second, an improved generative adversarial network (GAN) is trained to translate the distorted image into the non-distorted image. During this process, the attention mechanism and the weighted training objective are adopted in our GAN framework to get the high-quality restored results of distorted underwater images. The network is able to restore the colors and fine details in the distorted images by combining the three objective losses, i.e., the content loss, the adversarial loss, and the perceptual loss. Experimental results show that our proposed method outperforms other state-of-the-art methods on the validation set and our sea trial set.

13.
Nat Biomed Eng ; 4(12): 1197-1207, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33208927

RESUMO

Data from patients with coronavirus disease 2019 (COVID-19) are essential for guiding clinical decision making, for furthering the understanding of this viral disease, and for diagnostic modelling. Here, we describe an open resource containing data from 1,521 patients with pneumonia (including COVID-19 pneumonia) consisting of chest computed tomography (CT) images, 130 clinical features (from a range of biochemical and cellular analyses of blood and urine samples) and laboratory-confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) clinical status. We show the utility of the database for prediction of COVID-19 morbidity and mortality outcomes using a deep learning algorithm trained with data from 1,170 patients and 19,685 manually labelled CT slices. In an independent validation cohort of 351 patients, the algorithm discriminated between negative, mild and severe cases with areas under the receiver operating characteristic curve of 0.944, 0.860 and 0.884, respectively. The open database may have further uses in the diagnosis and management of patients with COVID-19.

14.
PLoS One ; 15(11): e0242164, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33180817

RESUMO

BACKGROUND AND OBJECTIVE: The relationship between antimitochondrial antibody (AMA) levels and the severity or prognosis of primary biliary cholangitis (PBC) is unclear. This study explored the clinical significance of serum IgG antimitochondrial M2 antibody (IgG-M2) levels. METHODS: From 2008 to 2017, a retrospective analysis was conducted with PBC patients who had available quantitative values of serum IgG-M2 levels obtained with ELISA based on triple expression hybrid clones. The patients were divided into two groups based on high and low concentrations of IgG-M2. Baseline parameters, the incidence of adverse events, and prognosis were compared. RESULTS: Among the 530 PBC patients, the levels of albumin, cholinesterase, hemoglobin, fibrinogen and triglycerides and the red blood cell count were significantly lower in the high-concentration group than in the low-concentration group (n = 263, 49.6%). The red cell distribution width (RDW) and levels of serum immunoglobulin (Ig) G, IgM and IgA were significantly higher in the high-concentration group than in the low-concentration group. Spearman's correlation analysis suggested that the correlation between the above baseline indicators and IgG-M2 levels was statistically significant but weak (r < 0.2, P < 0.05). In total, 203 patients were followed up, of whom 87 (42.9%) were in the high-concentration group. During the median follow-up period of 52 months (range: 28-75), 121 (59.6%) experienced hepatic decompensation, and 37 (18.2%) died or underwent liver transplantation. There was no significant difference in the incidence of complications or survival (log-rank test: P = 0.079) between the two groups. One year after ursodeoxycholic acid (UDCA) treatment, the two groups had similar responses. In addition, the levels of IgG-M2 did not fluctuate significantly during treatment. CONCLUSION: IgG-M2 levels were not related to the disease severity, prognosis or efficacy of UDCA. The levels of IgG-M2 did not change significantly during treatment.

15.
Genome Biol ; 21(1): 269, 2020 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-33143730

RESUMO

BACKGROUND: Long noncoding enhancer RNAs (lnc-eRNAs) are a subset of stable eRNAs identified from annotated lncRNAs. They might act as enhancer activity-related therapeutic targets in cancer. However, the underlying mechanism of epigenetic activation and their function in cancer initiation and progression remain largely unknown. RESULTS: We identify a set of lncRNAs as lnc-eRNAs according to the epigenetic signatures of enhancers. We show that these lnc-eRNAs are broadly activated in MLL-rearranged leukemia (MLL leukemia), an aggressive leukemia caused by a chromosomal translocation, through a mechanism by which the HOXA cluster initiates enhancer activity, and the epigenetic reader BRD4 cooperates with the coregulator MLL fusion oncoprotein to induce transcriptional activation. To demonstrate the functional roles of lnc-eRNAs, two newly identified lnc-eRNAs transcribed from the SEELA eRNA cluster (SEELA), SEELA1 and SEELA2, are chosen for further studies. The results show that SEELA mediated cis-activated transcription of the nearby oncogene Serine incorporate 2 (SERINC2) by directly binding to the K31 amino acid (aa) of histone H4. Chromatin-bound SEELA strengthens the interaction between chromatin and histone modifiers to promote histone recognition and oncogene transcription. Further studies show that the SEELA-SERINC2 axis regulated aspects of cancer metabolism, such as sphingolipid synthesis, to affect leukemia progression. CONCLUSIONS: This study shows that lnc-eRNAs are epigenetically activated by cancer-initiating oncoproteins and uncovers a cis-activating mechanism of oncogene transcription control based on lnc-eRNA-mediated epigenetic regulation of enhancer activity, providing insights into the critical roles of lnc-eRNAs in cancer initiation and progression.

16.
Sci Rep ; 10(1): 16484, 2020 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-33020497

RESUMO

The cytochrome cd1-containing nitrite reductase, nirS, plays an important role in biological denitrification. Consequently, investigating the presence and abundance of nirS is a commonly used approach to understand the distribution and potential activity of denitrifying bacteria, in addition to denitrifier communities. Herein, a rapid method for detecting nirS gene with loop-mediated isothermal amplification (LAMP) was developed, using Pseudomonas aeruginosa PAO1 (P. aeruginosa PAO1) as model microorganism to optimize the assay. The LAMP assay relied on a set of four primers that were designed to recognize six target sequence sites, resulting in high target specificity. The limit of detection for the LAMP assay under optimized conditions was 1.87 pg/reaction of genomic DNA, which was an order of magnitude lower than that required by conventional PCR assays. Moreover, it was validated that P. aeruginosa PAO1 cells as well as genomic DNA could be directly used as template. Only 1 h was needed from the addition of bacterial cells to the reaction to the verification of amplification success. The nirS gene of P. aeruginosa PAO1 in spiked seawater samples could be detected with both DNA-template based LAMP assay and cell-template based LAMP assay, demonstrating the practicality of in-field use.

17.
Appl Microbiol Biotechnol ; 104(23): 9979-9990, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33074415

RESUMO

Human connective tissue growth factor (CTGF) is a secreted cysteine-rich peptide that stimulates cell proliferation, migration, and extracellular matrix production during tissue development, differentiation, angiogenesis, implantation, wound healing, and fibrosis processes, with broad application in the medical and cosmetic medical fields. However, the production of CTGF is currently limited by its low yield and purity in current bioreactors. In this study, two genetically modified silkworm strains were generated harboring artificially designed CTGF-8ht and pepCTGF-8ht genes, respectively, that contain an enhanced His-tag with eight histidine residues with or without a transdermal peptide (pep). Both recombinant CTGF-8ht and pepCTGF-8ht proteins were successfully expressed in the silkworm silk gland and cocoon, and could be easily extracted and purified from the cocoon by single-affinity immunoprecipitation column chromatography, achieving a purity of more than 95%. Moreover, compared with CTGF-8ht protein, pepCTGF-8ht protein exhibited better cell proliferation activity by activating the extracellular signal-regulated kinase (ERK) pathway and enhanced hyaluronic acid synthesis activity by upregulating hyaluronan synthase 3 expression; moreover, the addition of pep significantly improved the transmembrane ability of CTGF-8ht protein. These results should help to promote the application prospects of CTGF and further guide the design and development of protein drugs from silkworm and other bioreactor systems. KEY POINTS : A silkworm bioreactor was optimized to produce connective tissue growth factor (CTGF) The transgene contained an enhanced 8-His-tag and transmembrane peptide (pep) Recombinant CTGF was easily purified with maintained or higher biological activity.

18.
IEEE Trans Biomed Eng ; PP2020 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-32997619

RESUMO

Patients after stroke may have different rehabilitation needs due to various levels of disability. To satisfy such needs, a performance-based hybrid control is proposed for a cable-driven upper-limb rehabilitation robot (CDULRR). The controller includes three working modes, i.e., resistance mode, assistance mode and restriction mode, which are switched by the tracking error since it is a common index to represent motor performance. In resistance mode, the proper damping force would be provided for subjects, which is in the opposite direction to the actual velocity. In assistance mode, a method of adjusting stiffness coefficient by fuzzy logic is adopted to provide suitable assistance to help subjects. In restriction mode, the damping force is applied again to limit the movement and ensure the safety. To verify the effectiveness of the controller, the task-oriented experiments with different disturbance were conducted by ten healthy subjects. The experiments results demonstrated that the controller can adjust working modes by the subjects' motor performance. It was found that, as the increasing disturbance led to a decrease in the motor performance, the robot provided more assistance in the trainings. Adaptive adjustment of damping force and stiffness coefficient allowed the controller to induce more active effort.

19.
Psychooncology ; 2020 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-32969126

RESUMO

OBJECTIVE: Women with breast cancer face elevated risk for psychological problems. We aimed to examine to what extent treatment-naïve women with breast cancer are at higher risk for perceived stress and symptoms of anxiety and depression, compared with matched women with benign breast disease and healthy women, and explore the contribution of perceived stress in the association between breast cancer and symptoms of anxiety and depression. METHODS: The study included 360 women (120 per group). Perceived stress and symptoms of anxiety and depression were assessed using self-report questionnaires. We conducted linear and logistic regressions to assess increased risk and mediation analyses to test the role of perceived stress. RESULTS: After adjusting for potential confounders, perceived stress in women with breast cancer was 0.71 and 1.58 points higher than in patients with benign breast disease (p = 0.029) and healthy controls (p < 0.001), respectively; they were 1.85-2.44 times more likely to experience anxiety than either control group (p< 0.05) and 3.57 times more likely to experience depression than healthy controls (p < 0.001). The indirect effect of perceived stress between breast cancer and anxiety and depressive symptoms was 0.19-0.47 (p < 0.05). CONCLUSIONS: This study demonstrates the high risk of perceived stress and symptoms of anxiety and depression in treatment-naïve patients with breast cancer, and the association between breast cancer and increased anxiety and depressive symptoms through elevated perceived stress. It underscores the need to assess psychological status in pretreatment period and conduct stress-targeted prehabilitation interventions.

20.
Clin Nurs Res ; : 1054773820951933, 2020 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-32799656

RESUMO

This study investigated the association between diabetes complications, diabetes distress, and depressive symptoms in patients with type 2 diabetes mellitus. A total of 600 patients with type 2 diabetes mellitus were included in this study. Data were collected using the Diabetes Distress Scale and the nine-item Patient Health Questionnaire. The results showed that both diabetes complications and diabetes distress were positively associated with depressive symptoms, and diabetes distress attenuated the association between diabetes complications and depressive symptoms. The Sobel test confirmed the mediating effect of diabetes distress. Patients with both diabetes complications and diabetes distress had a higher risk of depressive symptoms than those with diabetes complications or diabetes distress alone. This study indicates that the positive association between diabetes complications and depressive symptoms is persistent and mediated by diabetes distress, and the comorbidity of diabetes complications and diabetes distress has an additive interaction effect on depressive symptoms.

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