214 research outputs found

    Protective effect of quercetin on bupivacaine-induced neurotoxicity via T-type calcium channel inhibition

    Get PDF
    Purpose: To determine the effect of quercetin on bupivacaine-induced neurotoxicity and to investigate the mechanisms involved.Methods: Cultured SH-SY5Y cells were divided into five treatment groups: control group with no drug, bupivacaine treatment group, quercetin group, bupivacaine--quercetin combination treatment group, and bupivacaine-mibefradil combination treatment group. Cell morphology in each group was examined by microscopy while cell viability was assessed by 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2- tetrazolium bromide (MTT) assay after 24 h incubation. Cytosolic calcium ion concentration was determined by flow cytometry while Cav3.1 protein expression was evaluated by western blot.Results: Quercetin (50 ÎĽM) significantly (p < 0.05) protected SH-SYS5 cells from bupivacaine-induced cell apoptosis and also significantly reduced intracellular calcium ion concentration (p < 0.01) by approximately 40 %. Cav3.1 protein expression was normalized following quercetin treatment.Conclusion: These results show that quercetin reduces the neurotoxicity induced by bupivacaine, possibly through inhibition of T-type calcium channel. This finding implies a novel mechanism for neuroprotective effect of quercetin, and its potential for treating toxicity arising from the use of local anesthetic agents.Keywords: Quercetin, Bupivacaine, Local anaesthetic, Neuroprotection, Neurotoxicity, T-type calcium channe

    Erratum for “Protective effect of quercetin on bupivacaineinduced neurotoxicity via T-type calcium channel inhibition”

    Get PDF
    Jin et al Trop J Pharm Res 2017, 16(8): 1827-1833 http://dx.doi.org/10.4314/tjpr.v16i8.11The correct name of the First Author is Zhao as provided above and not Chao earlier published.Citation: Jin Z, Wu H, Tang C, Ke J, Wang Y. Protective effect of quercetin on bupivacaineinduced neurotoxicity via T-type calcium channel inhibition. Trop J Pharm Res 2017; 16(8):1827-1833 Erratum: 2017; 16(9):2051 http://dx.doi.org/10.4314/tjpr.v16i9.

    Roll-to-Roll Manufacturing of Robust Superhydrophobic Coating on Metallic Engineering Materials

    Get PDF
    Creating a robust superhydrophobic surface on the conventional engineering materials at mass production is of great importance for self–cleaning, anti–icing, non–wetting surface and low flow resistance in industrial applications. Herein, we report a roll–to–roll strategy to create durable and robust superhydrophobic surfaces with designed micro–/nano– scale hierarchical structures on many conventional engineering materials by combining electrical discharge machining, coating of carbon nanoparticles, and followed by oil penetration and drying. The treated surface shows good superhydrophobic properties with static water contact angle of 170±2o and slide angle of 3±1o. The treated surface also exhibits good resilience and maintains the performance after tested in various harsh conditions including water flushing for several days, sand abrasion, scratching with sandpapers and corrosive solution. Significantly, the superhydrophobic surfaces also shows a high efficiency of self–cleaning properties even after oil–contamination during applications

    A Novel Virtual Vector Modulation-based scheme of Model Power Predictive for VIENNA Rectifier

    Get PDF
    When the finite control set model predictive(FCS-MPC) algorithm is applied to the three-level converter, there are problems such as large current harmonics, high requirements for the computing efficiency of the micro-controller, complex multi-objective optimization and limited output vector switching. In additional, the mismatch of inductance parameter may directly affect the observation accuracy of FCS-MPC. Furthermore, due to the limitation of finite set model prediction, it leads to the switching operation is not constant and the decrease of the grid-connected current quality. In this regard, an improved model predictive direct power control based on the combined virtual vector modulation (MPDPC-VM) is proposed by considering the influence of the filter inductance parameter mismatch. The finite control set and restricted vector switching of the Vienna rectifier are modeled to avoid excessive voltage jumps, and the predicted values of input power is obtained by the sliding-mode control (SMC) strategy. Then, a linear synthesis method of virtual vector modulation-based scheme is proposed, which increases the number of the available voltage vectors in a single switching period from 8 to 19. The grid-connected current ripple is improved by reducing the error between the expected voltage vector and the available voltage vector. Finally, the model reference adaptive system (MRAS) method is applied to improve the working reliability and reduce the influence of mismatching of inductance parameters. Extensive simulation and matching experimental results is given to demonstrate the validity of the proposed strategy under steady-state and transient responses conditions compared against the existing FCS-MPC

    Clinical Study Intranasal Dexmedetomidine on Stress Hormones, Inflammatory Markers, and Postoperative Analgesia after Functional Endoscopic Sinus Surgery

    Get PDF
    Background. A strong ongoing intraoperative stress response can cause serious adverse reactions and affect the postoperative outcome. This study evaluated the effect of intranasally administered dexmedetomidine (DEX) in combination with local anesthesia (LA) on the relief of stress and the inflammatory response during functional endoscopic sinus surgery (FESS). Methods. Sixty patients undergoing FESS were randomly allocated to receive either intranasal DEX (DEX group) or intranasal saline (Placebo group) 1 h before surgery. Stress hormones, inflammatory markers, postoperative pain relief, hemodynamic variables, blood loss, surgical field quality, body movements, and satisfaction were assessed. Results. Plasma epinephrine, norepinephrine, and blood glucose levels were significantly lower in DEX group as were the plasma IL-6 and TNF-levels ( < 0.05). The weighted areas under the curve (AUCw) of the VAS scores were also significantly lower in DEX group at 2-12 h after surgery ( < 0.001). Furthermore, hemodynamic variables, blood loss, body movements, discomfort with hemostatic stuffing, surgical field quality, and satisfaction scores of patients and surgeons were significantly better ( < 0.05) in DEX group. Conclusions. Patients receiving intranasal DEX with LA for FESS exhibited less perioperative stress and inflammatory response as well as better postoperative comfort with hemostatic stuffing and analgesia

    Streptococcus suis contributes to inguinal lymph node lesions in piglets after highly pathogenic porcine reproductive and respiratory syndrome virus infection

    Get PDF
    The swine pathogens porcine reproductive and respiratory syndrome virus (PRRSV) and Streptococcus suis have both been reported to cause damage to the immune organs. Inguinal lymph node (ILN) injury has been reported in PRRSV-infected pigs with secondary S. suis infection, but not much is known about the mechanism. In this study, secondary S. suis infection after highly pathogenic (HP)-PRRSV infection caused more severe clinical symptoms, mortality, and ILN lesions. Histopathological lesions were seen in ILNs with a marked decrease in lymphocyte numbers. Terminal deoxynucleotidyl transferase (TdT)-mediated de-oxyuridine triphosphate (dUTP)-biotin nick end-labeling (TUNEL) assays revealed that HP-PRRSV strain HuN4 alone induced ILN apoptosis, but dual-infection with S. suis strain BM0806 induced greater levels of apoptosis. Besides, we found that some HP-PRRSV-infected cells underwent apoptosis. Furthermore, anti-caspase-3 antibody staining confirmed that ILN apoptosis was mainly induced by a caspase-dependent pathway. Pyroptosis was also observed in HP-PRRSV-infected cells, and there was more pyroptosis in piglets infected with HP-PRRSV alone compared with those with secondary S. suis infection, and HP-PRRSV-infected cells underwent pyroptosis. Altogether, this is the first report to identify pyroptosis in ILNs and which signaling pathway is related to ILN apoptosis in single or dual-infected piglets. These results contribute to a better understanding of the pathogenic mechanisms during secondary S. suis infection

    Direct Conversion of Fibroblasts to Neurons by Reprogramming PTB-Regulated MicroRNA Circuits

    Get PDF
    SummaryThe induction of pluripotency or trans-differentiation of one cell type to another can be accomplished with cell-lineage-specific transcription factors. Here, we report that repression of a single RNA binding polypyrimidine-tract-binding (PTB) protein, which occurs during normal brain development via the action of miR-124, is sufficient to induce trans-differentiation of fibroblasts into functional neurons. Besides its traditional role in regulated splicing, we show that PTB has a previously undocumented function in the regulation of microRNA functions, suppressing or enhancing microRNA targeting by competitive binding on target mRNA or altering local RNA secondary structure. A key event during neuronal induction is the relief of PTB-mediated blockage of microRNA action on multiple components of the REST complex, thereby derepressing a large array of neuronal genes, including miR-124 and multiple neuronal-specific transcription factors, in nonneuronal cells. This converts a negative feedback loop to a positive one to elicit cellular reprogramming to the neuronal lineage
    • …
    corecore