267 research outputs found

    RGD Peptide-Grafted Graphene Oxide as a New Biomimetic Nanointerface for Impedance-Monitoring Cell Behaviors

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    A new biomimetic nanointerface was constructed by facile grafting the bioactive arginylglycylaspartic acid (RGD) peptide on the graphene oxide (GO) surface through carbodiimide and N-hydroxysuccinimide coupling amidation reaction. The formed RGD-GO nanocomposites own unique two-dimensional structure and desirable electrochemical performance. The linked RGD peptides could improve GO’s biocompatibility and support the adhesion and proliferation of human periodontal ligament fibroblasts (HPLFs) on RGD-GO biofilm surface. Furthermore the biologically active RGD-GO nanocomposites were demonstrated as a potential biomimetic nanointerface for monitoring cell biobehaviors by electrochemical impedance spectroscopy (EIS). By analysis of the data obtained from equivalent circuit-fitting impedance spectroscopy, the information related to cell membrane capacitance, cell-cell gap resistance, and cell-electrode interface gap resistance in the process of cell adhesion and proliferation could be obtained. Besides, this proposed impedance-based cell sensor could be used to assess the inhibition effect of the lipopolysaccharide (LPS) on the HPLFs proliferation. Findings from this work suggested that RGD peptide functionalized GO nanomaterials may be not only applied in dental tissue engineering but also used as a sensor interface for electrochemical detection and analysis of cell behaviors in vitro

    Bone remodeling at microscrew interface near extraction site in the beagle dog mandible-histologic and immunohistochemical analyses

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    Extraction is often used as part of orthodontic therapy, and good control of anchorage is a key step after extraction. Although microscrews can be implanted close to the extraction site in order to achieve orthodontic support, the efficiency of bone remodeling at the implant-bone interface near the extraction region is dubious. OBJECTIVE: The purpose of this study was to investigate bone remodeling of the bone-microscrew interface near the tooth extraction site, in the absence of loading. MATERIAL AND METHODS: Third and fourth premolars were extracted from the mandibles of beagle dogs, followed by placement of test microscrews near the extraction sites. Control microscrews were placed further away from the extraction site. All samples were collected after 1, 3, 8, or 12 weeks of healing following extraction. The bone remodeling process at the interface was evaluated using histologic and immunohistochemical analyses. RESULTS: Initially, a large number of inflammatory cells were aggregated at the interface. The expression levels of core binding factor (Cbfa1), osteocalcin (OC) and transforming growth factor beta (TGF-ÎČ) were inconspicuous in both groups, whereas tumor necrosis factor alpha (TNF-α) was strongly expressed, especially in the test groups (

    Curcumin Inhibits Neuronal and Vascular Degeneration in Retina after Ischemia and Reperfusion Injury

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    Neuron loss, glial activation and vascular degeneration are common sequelae of ischemia-reperfusion (I/R) injury in ocular diseases. The present study was conducted to explore the ability of curcumin to inhibit retinal I/R injury, and to investigate underlying mechanisms of the drug effects.Different dosages of curcumin were administered. I/R injury was induced by elevating the intraocular pressure for 60 min followed by reperfusion. Cell bodies, brn3a stained cells and TUNEL positive apoptotic cells in the ganglion cell layer (GCL) were quantitated, and the number of degenerate capillaries was assessed. The activation of glial cells was measured by the expression level of GFAP. Signaling pathways including IKK-IÎșBα, JAK-STAT1/3, ERK/MAPK and the expression levels of ÎČ-tubulin III and MCP-1 were measured by western blot analysis. Pre-treatment using 0.01%-0.25% curcumin in diets significantly inhibited I/R-induced cell loss in GCL. 0.05% curcumin pre-treatment inhibited I/R-induced degeneration of retinal capillaries, TUNEL-positive apoptotic cell death in the GCL, brn3a stained cell loss, the I/R-induced up-regulation of MCP-1, IKKα, p-IÎșBα and p-STAT3 (Tyr), and down-regulation of ÎČ-tubulin III. This dose showed no effect on injury-induced GFAP overexpression. Moreover, 0.05% curcumin administered 2 days after the injury also showed a vaso-protective effect.Curcumin protects retinal neurons and microvessels against I/R injury. The beneficial effects of curcumin on neurovascular degeneration may occur through its inhibitory effects on injury-induced activation of NF-ÎșB and STAT3, and on over-expression of MCP-1. Curcumin may therefore serve as a promising candidate for retinal ischemic diseases

    Electrolyte Strategies Facilitating Anion‐Derived Solid‐Electrolyte Interphases for Aqueous Zinc–Metal Batteries

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    Rechargeable aqueous zinc–metal batteries (AZBs) are a promising complimentary technology to the existing lithium-ion batteries and the re-emerging lithium–metal batteries to satisfy the increasing demands on energy storage. Despite considerable progress achieved in the past years, the fundamental understanding of the solid-electrolyte interphase (SEI) formation and how its composition influences the SEI properties are limited. This review highlights the functionalities of anion-tuned SEI on the reversibility of zinc–metal anode, with a specific emphasis on new structural insights obtained through advanced characterizations and computational techniques. Recent efforts in terms of key variables that govern the interfacial behaviors to improve the long-term stability of zinc anode, i.e., Coulombic efficiency, plating morphology, dendrite formation, and side-reactions, are comprehensively reviewed. Lastly, the remaining challenges and future perspectives are presented, providing insights into the rational design of practical high-performance AZBs

    Endoplasmic reticulum stress in retinal vascular degeneration: protective role of resveratrol

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    A model-free direct predictive grid-current control strategy for grid-connected converter with an inductance-capacitance-inductance filter

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    The disadvantages of the conventional model predictive current control method for the grid-connected converter (GCC) with an inductance-capacitance-inductance (LCL) filter are a large amount of calculation and poor parameter robustness. Once parameters of the model are mismatched, the control accuracy of model predictive control (MPC) will be reduced, which will seriously affect the power quality of the GCC. The article intuitively analyzes the sensitivity of parameter mismatch on the current predictive control of the conventional LCL-filtered GCC. In order to solve these issues, a model-free predictive current control (MFPCC) method for the LCL-filtered GCC is proposed in this paper. The contribution of this work is that a novel current predictive robust controller for the LCL-filtered GCC is designed based on the principle of the ultra-local model of a single input single output system. The proposed control method does not require using any model parameters in the controller, which can effectively suppress the disturbances of the uncertain parameter variations. Compared with conventional MPC, the proposed MFPCC has smaller current total harmonic distortion (THD). When the filter parameters are mismatched, the control error of the proposed method is smaller. Finally, a comparative experimental study is carried out on the platform of Typhoon and PE-Expert4 to verify the superiority and effectiveness of the proposed MFPCC method for the LCL-filtered GCC

    Application effect of home-based rehabilitation program led by self-efficacy theory after temporomandibular joint disk repositioning

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    Objective·To explore the effects of home-based rehabilitation program led by self-efficacy theory after temporomandibular joint disk repositioning.Methods·Convenient sampling method was used. Patients with temporomandibular joint disk displacement who received temporomandibular joint disk repositioning in Shanghai Ninth Peopleâ€Čs Hospital, Shanghai Jiao Tong University School of Medicine from August 2020 to January 2021 were selected as the control group, and patients admitted from February 2021 to July 2021 were selected as the intervention group. The control group received the conventional home-based rehabilitation care, while the intervention group were given home-based rehabilitation program led by self-efficacy theory. The general information questionnaire was used to collect the general information about patients. The joint range of motion measuring, rehabilitation exercise compliance questionnaire, General Self-efficacy Scale (GSES), and Mishel's Uncertainty in Illness Scale (MUIS) were used to investigate the joint range of motion, the rehabilitation exercise compliance score, the self-efficacy score and the uncertainty in illness score in the two groups at baseline and at 1, 3 and 6 months after surgery.Results·A total of 167 patients with temporomandibular joint disk displacement who received temporomandibular joint disk repositioning surgery were enrolled, including 96 cases in the control group and 71 cases in the intervention group. There was no difference in the general information between the two groups (P>0.05). There were no differences in the maximal mouth opening, maximum rightward lateral movement, maximum leftward lateral movement, self-efficacy score and uncertainty in illness score between the two groups at baseline (all P>0.05). The maximal forward extension in the intervention group was significantly less than that in the control group (P=0.008). Repeated measurement variance analysis showed that the self-efficacy scores in the intervention group were higher than those in the control group at 1, 3 and 6 months after surgery, and the differences were statistically significant (P=0.006, P=0.003, P=0.016). At 1 and 3 months after surgery, the scores of complexity dimension of uncertainty in illness in the intervention group were significantly lower than those in the control group (P=0.003, P=0.000). At 1 and 6 months after surgery, the rehabilitation exercise compliance scores in the intervention group were significantly higher than those in the control group (P=0.000, P=0.016). At 6 months after surgery, the maximum forward extension and maximum rightward lateral movement were significantly greater than those in the control group (P=0.024, P=0.008).Conclusion·The home-based rehabilitation program led by self-efficacy theory has a positive effect on improving the self-efficacy and compliance of rehabilitation exercise, reducing the disease uncertainty, and promoting the joint function recovery in patients receiving temporomandibular joint disk repositioning

    Tumor grade-associated genomic mutations in Chinese patients with non-small cell lung cancer

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    BackgroundLung cancer is the most prevalent cancer worldwide and accounts for approximately 20% of cancer-related death in China every year. High-grade lung cancer poses a significant threat to patients, and developing a novel treatment for these patients requires an understanding of its underlying mechanism.MethodsChinese patients with lung cancer were enrolled. The tumor samples were collected by surgery or puncture and applied for next-generation sequencing. A panel of pan-cancer genes was targeted, and the sequencing depth was set to over 1,000 to improve the sensitivity of detecting mutations. Short-length mutations (substitution, insertion, and deletion), copy number variation, and gene fusion were called. Gene mutations were compared between low-grade, middle-grade, and high-grade tumors using Fisher’s exact test. The enriched pathways in each grade of tumors were also inferred.ResultsThe study included 173 Chinese patients with non-small cell lung cancer, of whom 98 (56.6%) patients were female and 75 (43.4%) were male, with a mean age of 56.8 years. All patients were microsatellite stable; 66.4% were at the early stages (Stages 0, I, and II) with a tumor mutational burden of approximately 2.5 (confidence interval = [0, 48.3]). Compared to low-grade tumors, high-grade tumors had a significantly higher percentage of mutations in TP53 (75.9% vs 34.4%, p = 1.86e-3) and PIK3CA (24.1% vs. 0%, p = 3.58e-3). Pathway analysis found that high-grade tumors were enriched with mutations in bacterial invasion of epithelial cells (31% vs. 0%, p = 5.8e-4), Epstein–Barr virus infection (79.3% vs. 37.5%, p = 1.72e-3), and the Wnt signaling pathway (75.9% vs. 34.4%, p = 1.91e-3). High-grade tumors had a significantly higher tumor mutational burden than low-grade tumors (p-value = 0.0017). However, actionable mutations with high-level evidence were lower in high-grade tumors.ConclusionPatients with high-grade tumors from lung cancer may be more affected by bacteria and Epstein–Barr virus than low-grade tumors. High-grade tumors were specially mutated in TP53 and PIK3CA and may benefit more from immunotherapy. Further research on the underlying mechanism of high-grade lung cancer is necessary to develop new therapeutic options. Lung cancer, tumor grade, genomic mutations, Epstein–Barr virus, pathway analysi

    Several Critical Cell Types, Tissues, and Pathways Are Implicated in Genome-Wide Association Studies for Systemic Lupus Erythematosus

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    We aimed to elucidate the cell types, tissues, and pathways influenced by common variants in systemic lupus erythematosus (SLE). We applied a nonparameter enrichment statistical approach, termed SNPsea, in 181 single nucleotide polymorphisms (SNPs) that have been identified to be associated with the risk of SLE through genome-wide association studies (GWAS) in Eastern Asian and Caucasian populations, to manipulate the critical cell types, tissues, and pathways. In the two most significant cells’ findings (B lymphocytes and CD14+ monocytes), we subjected the GWAS association evidence in the Han Chinese population to an enrichment test of expression quantitative trait locus (QTL) sites and DNase I hypersensitivity, respectively. In both Eastern Asian and Caucasian populations, we observed that the expression level of SLE GWAS implicated genes was significantly elevated in xeroderma pigentosum B cells (P ≀ 1.00 × 10−6), CD14+ monocytes (P ≀ 2.74 × 10−4) and CD19+ B cells (P ≀ 2.00 × 10−6), and plasmacytoid dendritic cells (pDCs) (P ≀ 9.00 × 10−6). We revealed that the SLE GWAS-associated variants were more likely to reside in expression QTL in B lymphocytes (q1/q0 = 2.15, P = 1.23 × 10−44) and DNase I hypersensitivity sites (DHSs) in CD14+ monocytes (q1/q0 = 1.41, P = 0.08). We observed the common variants affected the risk of SLE mostly through by regulating multiple immune system processes and immune response signaling. This study sheds light on several immune cells and responses, as well as the regulatory effect of common variants in the pathogenesis of SLE
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