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1.
J Chromatogr A ; 1722: 464863, 2024 May 10.
Article in English | MEDLINE | ID: mdl-38626538

ABSTRACT

Volatile organic compounds (VOCs) are a group of ubiquitous environment pollutants especially released into the workplace. Assessment of VOCs exposure in occupational populations is therefore a crucial issue for occupational health. However, simultaneous biomonitoring of a variety of VOCs is less studied. In this study, a simple and sensitive method was developed for the simultaneous determination of 51 prototype VOCs in urine by headspace-thermal desorption coupled to gas chromatography-mass spectrometry (HS-TD-GC-MS). The urinary sample was pretreated with only adding 0.50 g of sodium chloride to 2 mL of urine and 51 VOCs should be determined with limits of detection (LODs) between 13.6 ng/L and 24.5 ng/L. The method linearity ranged from 0.005 to 10 µg/L with correlation coefficients (r) of 0.991 to 0.999. The precision for intraday and inter-day, measured by the variation coefficient (CV) at three levels of concentration, was below 15 %, except for 4-isopropyl toluene, dichloromethane, and trichloromethane at low concentration. For medium and high levels, recoveries of all target VOCs were within the standard range, but 1,1-dichloropropene and styrene, which were slightly under 80 % at low levels. In addition, the proposed method has been used to determine urine samples collected in three times (before, during and after working) from 152 workers at four different factories. 41 types of prototype VOCs were detected in workers urine. Significant differences (Kruskal-Wallis chi-squared = 117.18, df = 1, P < 0.05) in the concentration levels of VOCs between the exposed and unexposed groups were observed, but not between the three sampling times (Kruskal-Wallis chi-squared = 3.39, df = 2, P = 0.183). The present study provides an alternative method for biomonitoring and assessing mixed exposures to VOCs in occupational populations.


Subject(s)
Gas Chromatography-Mass Spectrometry , Limit of Detection , Occupational Exposure , Volatile Organic Compounds , Humans , Volatile Organic Compounds/urine , Gas Chromatography-Mass Spectrometry/methods , Occupational Exposure/analysis , Reproducibility of Results , Adult , Biological Monitoring/methods , Male
2.
Biosens Bioelectron ; 253: 116173, 2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38432075

ABSTRACT

Since the emergence of single-cell electroanalysis, the two-electrode system has become the predominant electrochemical system for real-time behavioral analysis of single-cell and multicellular populations. However, due to the transmembrane placement of the two electrodes, cellular activities can be interrupted by the transmembrane potentials, and the test results are susceptible to influences from factors such as intracellular solution, membrane, and bulk solution. These limitations impede the advancement of single-cell analysis. Here, we propose a highly miniaturized and integrated in situ self-referenced intracellular two-electrode system (IS-SRITES), wherein both the working and reference electrodes are positioned inside the cell. Additionally, we demonstrated the stability (0.28 mV/h) of the solid-contact in situ Ag/AgCl reference electrode and the ability of the system to conduct standard electrochemical testing in a wide pH range (pH 6.0-8.0). Cell experiments confirmed the non-destructive performance of the electrode system towards cells and its capacity for real-time monitoring of intra- and extracellular pH values. Moreover, through equivalent circuits, finite element simulations, and drug delivery experiments, we illustrated that the IS-SRITES can yield more accurate test results and exhibit enhanced resistance to interference from the extracellular environment. Our proposed system holds the potential to enable the precise detection of intracellular substances and optimize the existing model of the electrode system for intracellular signal detection, thereby spearheading advancements in single-cell analysis.


Subject(s)
Biosensing Techniques , Biosensing Techniques/methods , Electrodes , Single-Cell Analysis
3.
ACS Nano ; 17(22): 22277-22286, 2023 11 28.
Article in English | MEDLINE | ID: mdl-37930063

ABSTRACT

Perioperative cerebral hypoxia and neonatal hypoxia-ischemic encephalopathy are the main triggers that lead to temporary or permanent brain dysfunction. The pathogenesis is intimately correlated to neural activities and the pH of the microenvironment, which calls for a high demand for in situ multitype physiological signal acquisition in the brain. However, conventional pH sensing neural interfaces cannot obtain the characteristics of multimodes, multichannels, and high spatial resolution of physiological signals simultaneously. Here, we report a multifunctional implantable iridium oxide (IrOx) neural probe (MIIONP) combined with electrophysiology recording, in situ pH sensing, and neural stimulation for real-time dynamic brain hypoxia evaluation. The neural probe modified with IrOx films exhibits outstanding electrophysiology recording and neural stimulation performance and long-term stable high spatial pH sensing resolution of about 100 µm, and the cytotoxicity of IrOx microelectrodes was investigated as well. In addition, 4 weeks' tracking of the same neuron firing and instantaneous population spike captured during electrical stimulation was achieved by MIIONP. Finally, in a mouse brain hypoxia model, the MIIONP has demonstrated the capability of synchronous in situ recording of the pH and neural firing changes in the brain, which has a valuable application in dynamic brain disease evaluation through real-time acquisition of multiple physiological signals.


Subject(s)
Brain Diseases , Hypoxia, Brain , Mice , Animals , Microelectrodes , Prostheses and Implants , Iridium , Hypoxia, Brain/diagnostic imaging
4.
Dalton Trans ; 52(43): 15839-15847, 2023 Nov 07.
Article in English | MEDLINE | ID: mdl-37819679

ABSTRACT

Carbon materials have a very wide range of applications in the field of electrocatalysis, both as catalyst bodies and as excellent supports for catalysts. In this work, we obtained a graphitic-like orange-peel derived carbon (OPC) material through pre-carbonization and KOH activation strategies using discarded orange-peel as a raw material. OPC has good graphitization characteristics and a few-layer structure, making it very suitable as a support for nanoparticle catalysts. In order to compare the performance of OPC, we used commercial graphene as the benchmark, made two carbon materials uniformly loaded with ruthenium nanoparticles under the same conditions, and obtained two HER catalysts (Ru/OPC and Ru/rGO). The results indicate that Ru/OPC has excellent HER catalytic performance under alkaline conditions, not only superior to Ru/rGO, but also surpassing commercial Pt/C. In 1 M KOH; the overpotential of Ru/OPC is only 3 mV at -10 mA cm-2, greatly exceeding those of Ru/rGO (100 mV) and Pt/C (31 mV). Under high current density (j), the performance of Ru/OPC is even better; the overpotential is 79 mV and 136 mV at -100 mA cm-2 and -200 mA cm-2, respectively. More importantly, Ru/OPC also has a very high TOF and long-term stability, with a TOF of up to 10.62 H2 s-1 at an overpotential of 100 mV and almost no attenuation after 72 h of operation at -50 mA cm-2. Ru/OPC also exhibits good catalytic performance under acidic conditions, significantly superior to that of Ru/rGO. For Ru/OPC, the overpotential is 86 mV, 167 mV and 214 mV at -10 mA cm-2, -100 mA cm-2 and -200 mA cm-2, respectively. Under the same conditions, the overpotential of Ru/rGO is 143 mV, 253 mV and 306 mV at -10 mA cm-2, -100 mA cm-2 and -200 mA cm-2, respectively.

6.
Neurosci Bull ; 39(11): 1683-1702, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37523099

ABSTRACT

Parvalbumin interneurons belong to the major types of GABAergic interneurons. Although the distribution and pathological alterations of parvalbumin interneuron somata have been widely studied, the distribution and vulnerability of the neurites and fibers extending from parvalbumin interneurons have not been detailly interrogated. Through the Cre recombinase-reporter system, we visualized parvalbumin-positive fibers and thoroughly investigated their spatial distribution in the mouse brain. We found that parvalbumin fibers are widely distributed in the brain with specific morphological characteristics in different regions, among which the cortex and thalamus exhibited the most intense parvalbumin signals. In regions such as the striatum and optic tract, even long-range thick parvalbumin projections were detected. Furthermore, in mouse models of temporal lobe epilepsy and Parkinson's disease, parvalbumin fibers suffered both massive and subtle morphological alterations. Our study provides an overview of parvalbumin fibers in the brain and emphasizes the potential pathological implications of parvalbumin fiber alterations.


Subject(s)
Epilepsy, Temporal Lobe , Parkinson Disease , Mice , Animals , Epilepsy, Temporal Lobe/pathology , Parvalbumins/metabolism , Parkinson Disease/pathology , Neurons/metabolism , Interneurons/physiology , Disease Models, Animal , Brain/pathology
7.
Acta Pharmaceutica Sinica ; (12): 1496-1504, 2023.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-978732

ABSTRACT

To investigate the cardioprotective effect of formononetin (FMN) on no-reflow (NR) after myocardial ischemia-reperfusion and its molecular mechanism based on integrated pharmacology and experimental verification, firstly, human breast cancer MCF-7 cells and myocardial NR rats were used to confirm the estrogenic activity and the effect of alleviating NR of FMN, respectively. Male SD rats were divided into Sham, NR, FMN (20 mg·kg-1) and sodium nitroprusside (SNP, 5.0 mg·kg-1) groups, which were administered once a day for one week, the experiment was approved by the Ethics Committee of Tianjin University of Traditional Chinese Medicine (TCM-LAEC2019095). The pharmacological analysis and in vivo study of NR rats were integrated to reveal the mechanism of FMN improving NR. The results showed that FMN had estrogenic effect and reduced NR by improving cardiac structure and function, reducing NR, ischemic myocardial area and pathological injury of cardiomyocytes. Integrated pharmacology predicts that the mechanism of FMN improving NR is mainly related to phosphatidyinositol-3-kinase-protein kinase B (PI3K-Akt) signal pathway. Phytoestrogens play a role in cardiovascular protection mainly by activating G protein-coupled estrogen receptor (GPER). GPER is also an important regulator in the upstream of PI3K-Akt signaling pathway. This study found that FMN can significantly activate GPER, p-PI3K, p-Akt and phospho-endothelial nitric oxide synthase (p-eNOS). It has good binding ability with GPER and eNOS protein. In this study, through the integration of pharmacology and experimental evaluation, it is revealed that FMN activates PI3K/Akt/eNOS signal pathway by activating GPER, thus significantly improving NR.

8.
Microsyst Nanoeng ; 8: 133, 2022.
Article in English | MEDLINE | ID: mdl-36575664

ABSTRACT

Implantable brain-computer interface (BCI) devices are an effective tool to decipher fundamental brain mechanisms and treat neural diseases. However, traditional neural implants with rigid or bulky cross-sections cause trauma and decrease the quality of the neuronal signal. Here, we propose a MEMS-fabricated flexible interface device for BCI applications. The microdevice with a thin film substrate can be readily reduced to submicron scale for low-invasive implantation. An elaborate silicon shuttle with an improved structure is designed to reliably implant the flexible device into brain tissue. The flexible substrate is temporarily bonded to the silicon shuttle by polyethylene glycol. On the flexible substrate, eight electrodes with different diameters are distributed evenly for local field potential and neural spike recording, both of which are modified by Pt-black to enhance the charge storage capacity and reduce the impedance. The mechanical and electrochemical characteristics of this interface were investigated in vitro. In vivo, the small cross-section of the device promises reduced trauma, and the neuronal signals can still be recorded one month after implantation, demonstrating the promise of this kind of flexible BCI device as a low-invasive tool for brain-computer communication.

9.
Chinese Pharmacological Bulletin ; (12): 893-897, 2022.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-1014088

ABSTRACT

Aim To evaluate the effects of puerarin (PR) on pancreatic islet MIN6 cell injury and apopto- sis induced by palmitic acirl ( PA).Methods MIN6 cells pretreated with 2 h different concentrations of PR were then co-cultured with 120 (xmol • L"1 PA for 24 h to establish the cell injury and apoptosis model.MTT, LDH,MDA and GSH were used to determine the dam¬age of MIN6 cells.AOEB fluorescence staining was used to detect the apoptosis of MIN6 cells.Western blot was used to detect the expressions of inflammation- related protein NF-kB , apoptosis-related factors Bcl-2 and Bax.Results Compared with model group, cell viability and GSH activity of puerarin administration groups increased, LDH and MDA contents decreased.the protein expressions of p-NF-KB and Bax were down-regulated, and the protein expressions of Bcl-2 were up-regulated (P <0.05).Conclusions Puerar- in ean improve the function of pancreatic islet cells by inhibiting apoptosis and inflammation, and ameliorate pancreatic islet MIN6 cell injury and apoptosis induced by palmitic acid-induced, alleviate MIN6 cell injury in¬duced by inflammatory factors, which may be achieved by down-regulating the expression of p-NF-KB and Bax proteins,and up-regulating the expression of Bcl-2 pro¬tein.

10.
Aging Cell ; 20(10): e13434, 2021 10.
Article in English | MEDLINE | ID: mdl-34528746

ABSTRACT

MicroRNAs (miRNAs) are small noncoding RNAs ubiquitously expressed in the brain and regulate gene expression at the post-transcriptional level. The nuclear RNase III enzyme Drosha initiates the maturation process of miRNAs in the nucleus. Strong evidence suggests that dysregulation of miRNAs is involved in many neurological disorders including Alzheimer's disease (AD). Dysfunction of miRNA biogenesis components may be involved in the processes of those diseases. However, the role of Drosha in AD remains unknown. By using immunohistochemistry, biochemistry, and subcellular fractionation methods, we show here that the level of Drosha protein was significantly lower in the postmortem brain of human AD patients as well as in the transgenic rat model of AD. Interestingly, Drosha level was specifically reduced in neurons of the cortex and hippocampus but not in the cerebellum in the AD brain samples. In primary cortical neurons, amyloid-beta (Aß) oligomers caused a p38 MAPK-dependent phosphorylation of Drosha, leading to its redistribution from the nucleus to the cytoplasm and a decrease in its level. This loss of Drosha function preceded Aß-induced neuronal death. Importantly, inhibition of p38 MAPK activity or overexpression of Drosha protected neurons from Aß oligomers-induced apoptosis. Taken together, these results establish a role for p38 MAPK-Drosha pathway in modulating neuronal viability under Aß oligomers stress condition and implicate loss of Drosha as a key molecular change in the pathogenesis of AD.


Subject(s)
Alzheimer Disease/genetics , Amyloid beta-Peptides/metabolism , Ribonuclease III/metabolism , p38 Mitogen-Activated Protein Kinases/metabolism , Animals , Humans , Rats , Rats, Transgenic
11.
Sensors (Basel) ; 21(15)2021 Jul 23.
Article in English | MEDLINE | ID: mdl-34372233

ABSTRACT

pH value plays an important role in many fields such as chemistry and biology; therefore, rapid and accurate pH measurement is very important. Because of its advantages in preparation, wide test range, rapid response, and good biocompatibility, iridium oxide material has received more and more attention. In this paper, we present a method for preparing iridium oxide pH microelectrodes based on the sputter deposition method. The sputtering parameters of iridium oxide are also studied and optimized. Open-circuit potential tests show that microelectrodes exhibit near-Nernstian pH response with good linearity (about 60 mV/pH), fast response, high stability (a slight periodic fluctuation of potential change <2.5 mV in 24 h), and good reversibility in the pH range of 1.00-13.00.


Subject(s)
Iridium , Hydrogen-Ion Concentration , Microelectrodes
12.
Biochem Biophys Res Commun ; 556: 149-155, 2021 06 04.
Article in English | MEDLINE | ID: mdl-33839410

ABSTRACT

Secondary injury is the main cause of high mortality and poor prognosis of TBI, which has recently been suggested to be related to ferroptosis. Polydatin, a monocrystalline compound extracted from the rhizome of Polygonum, has been shown to exert potential neuroprotective effects. However, its role and mechanism in the secondary injury of TBI has not been elucidated. In this study, the inhibition of Polydatin on ferroptosis was observed both in the hemoglobin treated Neuro2A cells in vitro and in TBI mouse model in vivo, characterized by reversion of accumulation or deposition of free Fe2+, increased content of MDA, decreased activity of key REDOX enzyme GPx4, cell death and tissues loss. Although Polydatin corrected the increased mRNA levels of ferroptosis signaling molecules GPX4, SLC7A11, PTGS2, and ATP5G3 after TBI, TBI and Polydatin treatment had no significant effect on their protein expression. Notably, Polydatin could completely reverse the decrease of GPx4 activity after TBI in vivo and in vitro, and the effect was stronger than that of the classical ferroptosis inhibitor FER-1 in vitro. Further, Polydatin has been shown to reduce the severity of acute neurological impairment and significantly improve subacute motor dysfunction in TBI mice. Our findings provided translational insight into neuroprotection with Polydatin in TBI by inhibiting ferroptosis mainly depending on the maintenance of GPx4 activity.


Subject(s)
Brain Injuries, Traumatic/drug therapy , Brain Injuries, Traumatic/prevention & control , Ferroptosis/drug effects , Glucosides/pharmacology , Glucosides/therapeutic use , Neuroprotection/drug effects , Neuroprotective Agents/pharmacology , Stilbenes/pharmacology , Stilbenes/therapeutic use , Animals , Brain/drug effects , Brain/physiology , Brain Injuries, Traumatic/physiopathology , Cell Line , Cell Survival/drug effects , Disease Models, Animal , Hemin/pharmacology , Iron/metabolism , Male , Mice , Mice, Inbred C57BL , Neurons/drug effects , Neurons/pathology , Neuroprotective Agents/therapeutic use , Phospholipid Hydroperoxide Glutathione Peroxidase/metabolism
13.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-880119

ABSTRACT

OBJECTIVE@#To detecte the carrying rate, the type and distribution of α-Thalassemia gene mutation in Honghe Prefecture, Yunnan Province, and analyze the differences in average erythrocyte volume (MCV), mean erythrocyte hemoglobin content (MCH) and hemoglobin among different types of α-Thalassemia.@*METHODS@#The DNA samples from small cell hypochromic carriers or anemia patients and women of childbearing age who underwent hematological screening in The First People's Hospital of Honghe State was from 2015 to 2019 were enrolled and analyzed, and the mutation types and frequency of alpha-thalassemia positive rate were diagnosed by PCR reverse dot blot or PCR fluorescence dissolution curve.@*RESULTS@#Among the 1 016 samples, 141(13.88%) of the patients were diagnosed as α-thalassemia. The α-thalassemia was subdivided into 3 types, silent (36.17%), minor (51.77%), and HbH disease (12.06%), and the MCV, MCH and HB levels were detected and showed a obvious decrease trend with significant difference (P < 0.05). The gene mutation types were 9 kinds, the deletion type gene was mainly --SEA (51.06%), followed by -α@*CONCLUSION@#Alpha-thalassemia in Honghe prefecture of Yunnan Province shows complex genetic diversity and significant genetic heterogeneity, and the mainly type of gene mutation is --SEA and --


Subject(s)
Female , Humans , China , Genotype , Heterozygote , Mutation , alpha-Thalassemia/genetics , beta-Thalassemia
14.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-1015097

ABSTRACT

AIM: To investigate the polymorphism distribution of lipid and drug metabolism-related genes of SLCO1B1 and ApoE in patients with cardiovascular disease of Han nationality in Anhui province, and to evaluate the benefit-risk ratio of individual use of statins. METHODS: PCR fluorescence probe technique was used to detect the genetic polymorphism of rs2306283 (388A>G) and rs4149056 (521T>C) of SLCO1B1 as well as rs429358 (388 T>C) and rs7412 (526C>T) of ApoE in 736 individuals diagnosed with cardiovascular diseases in the inpatient department of the Second People's Hospital of Hefei from January 2019 to August 2020 were included. The distribution characteristics of SLCO1B1 and ApoE genotypes were analyzed according to the gender of the subjects, and the results of genetic polymorphism were compared with the data of cardiovascular disease patients in other areas of China. RESULTS: Six genotypes of SLCO1B1 had been detected. They were *1a/*1a (6.11%), *1a/*1b (29.08%), *1b/*1b (44.57%), *1a/*15 (4.08%), *1b/*15 (15.49%) and *15/*15 (0.68%), while *1a/*5, *5/*5 and *5/*15 had not been detected. Six genotypes of ApoE had been detected. They were E2/E2 (0.41%), E2/E3 (11.96%), E2/E4 (1.09%), E3/E3 (67.66%), E3/E4 (17.93%) and E4/E4 (0.95%). The frequency distribution of genetic polymorphism of these two genes satisfied the Hardy-Weinberg genetic equilibrium, which was representative of the population. In this study, the proportion of people with SLCO1B1 normal myopathy risk was the highest, accounting for 79.76%; SLCO1B1 had a lower proportion of people with moderate myopathy risk and high myopathy risk were 19.57% and 0.68%, respectively. The reduced risk, normal risk and increased risk phenotypes of ApoE were respectively 12.37%, 68.75% and 18.88%. There was no statistically significant difference in SLCO1B1 and ApoE genotypes beween gender. Compared with patients with cardiovascular disease in Southern China area, the distribution of ApoE genetic polymorphism was significantly different in Anhui. CONCLUSION: The SLCO1B1 and ApoE genetic polymorphism of 736 patients with cardiovascular diseases in Anhui were mainly normal myopathy risk types with higher dose tolerance of statins as well as popular genotypes that were sensitive to statins, and the application of statins has a lower risk of myopathy and a good effect on lipid reduction. The polymorphism of the two genes was not affected by gender, but the distribution phenotypes of ApoE might be different in regional characteristics. The detection of SLCO1B1 and ApoE genetic polymorphism is significant for evaluation of benefit-risk ratios, thereby guiding statins clinical treatment.

15.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-942443

ABSTRACT

Objective: To study the effects of superficial temporal artery and vein as recipient vessels for the free anterolateral thigh flap on the appearance and functions after maxillectomy. Methods: Clinical data of 21 patients with malignant maxillary tumors in Department of Oral and Maxillofacial Surgery, the Second Xiangya Hospital of Central South University from January 2014 to November 2019, who were treated by free anterolateral thigh flap with temporal superficial vessels as the recipient vessels were analyzed retrospectively. There were 18 males and 3 females, with the age ranging from 29 to 73 years old, including 19 cases of squamous carcinoma, 1 case of adenoid cystic carcinoma and 1 case of osteosarcoma. Of those 7 patients underwent primary surgery, 14 patients received resurgery, and 6 patients had a history of postoperative radiotherapy and chemotherapy. Among 14 patients with resurgery, 13 had recurrent ipsilateral second site tumor and 1 had recurrent tumor, and all of them received the maxillectomy and reconstructive surgery with the free anterolateral thigh flap. Patients were evaluated with water swallow test and speech intelligibility score in 1, 3 and 6 months after operation. The data were statistically analyzed with SPSS 22.0 statistical software. Water swallow test results before and after operation were compared using the Wilcoxon rank sum test. The mean speech intelligibility scores before and after operation were compared by the paired t test. Results: Patients were followed up for 10-60 months. All free flaps survived after operation. No diplopia occurred. Breathing, swallowing and speaking functions were normal. No movement disorders caused by the donor of thigh flap. Water swallow test showed no phenomenon of water flowing into the nasal cavity or oral and nasal leakage with level Ⅰ for 4 cases, level Ⅱ for 13 cases, level Ⅲ for 3 cases and level Ⅳ for 1 case. The mean speech intelligibility scores before surgery and 1, 3 and 6 months after surgery were 4.31±0.13, 1.46±0.21, 2.15±0.45 and 2.87±0.76 respectively. There was statistically significant difference in the mean speech intelligibility scores between 1 and 6 months after surgery (F=78.456, P<0.05). Conclusion: It is safe and reliable to use the superficial temporal vessels as recipient vessels for free anterolateral thigh flap in the reconstruction of defect after maxillectomy in malignant tumors, with good outcomes of functions and a satisfactory restoration of outward appearance.


Subject(s)
Adult , Aged , Female , Humans , Male , Middle Aged , Free Tissue Flaps , Neoplasm Recurrence, Local , Plastic Surgery Procedures , Retrospective Studies , Skin Transplantation , Thigh/surgery
16.
Micromachines (Basel) ; 10(4)2019 Apr 11.
Article in English | MEDLINE | ID: mdl-30979081

ABSTRACT

Signal recording and stimulation with high spatial and temporal resolution are of increasing interest with the development of implantable brain-computer interfaces (BCIs). However, implantable BCI technology still faces challenges in the biocompatibility and long-term stability of devices after implantation. Due to the cone structure, needle electrodes have advantages in the biocompatibility and stability as nerve recording electrodes. This paper develops the fabrication of Ag needle micro/nano electrodes with a laser-assisted pulling method and modifies the electrode surface by electrochemical oxidation. A significant impedance reduction of the modified Ag/AgCl electrodes compared to the Ag electrodes is demonstrated by the electrochemical impedance spectrum (EIS). Furthermore, the stability of modified Ag/AgCl electrodes is confirmed by cyclic voltammogram (CV) scanning. These findings suggest that these micro/nano electrodes have a great application prospect in neural interfaces.

17.
Front Neurosci ; 12: 582, 2018.
Article in English | MEDLINE | ID: mdl-30210273

ABSTRACT

Infrasound, a kind of ambient noise, can cause severe disorders to various human organs, specially to central nervous system (CNS). Our previous studies have shown that infrasound-induced CNS injury was closely related with astrocytes activation and astrocytes-mediated neuroinflammation, but the underlying molecular mechanisms are still largely unclear. FGF2/FGFR1 (Fibroblast growth factor 2/Fibroblast growth factor receptor 1) pathway was reported to play an important role in anti-inflammation in CNS disorders. To further study the possible roles of FGF2/FGFR1 pathway in infrasound-induced CNS injury, here we exposed Sprague-Dawley rats or cultured astrocytes to 16 Hz, 150 dB infrasound, and explored the effects of FGF2 on infrasound-induced astrocytes activation and neuroinflammation. Western blotting, immunofluorescence and liquid chip method were used in this experiment. Our results showed that after 3- or 7-day exposure (2 h/day) of rats as well as 2 h exposure of cultured astrocytes to 16 Hz, 150 dB infrasound, astrocyte-expressed FGFR1 was downregulated in vivo and in vitro. FGF2 pretreatment not only inhibited infrasound-induced astrocyte activation in rat hippocampal CA1 region, but also reduced the levels of pro-inflammatory cytokines, such as TNF-α, IL-1ß, IL-18, IL-6, and IFN-γ in vitro and in vivo. However, FGF2 significantly upregulated the expression of FGFR1. Furthermore, we showed that FGF2 could attenuate IκBα phosphorylation, NF-κB p65 translocation, pro-inflammatory cytokines levels, and neuronal loss in the CA1 region induced by infrasound. On the contrary, PD173074, a special antagonist of FGFR1, could reverse the effects above in vitro and in vivo. Taken together, our findings showed that FGF2/FGFR1 pathway may exert inhibitive effects on astrocyte-mediated neuroinflammation in vitro and in vivo after infrasound exposure.

18.
Int J Biol Macromol ; 118(Pt B): 1501-1510, 2018 Oct 15.
Article in English | MEDLINE | ID: mdl-30170363

ABSTRACT

Polysaccharides are the main active component of the Mongolian medicine Fructus Meliae Toosendan, but their effective extraction and antioxidant effects have not been reported. Therefore, the optimization of the microwave extraction of polysaccharides from Fructus Meliae Toosendan (FMTP) using the response interface method was carried out. Single-factor tests on four main factors (the solid-liquid ratio, microwave power, extraction time, and number of extractions) affecting the polysaccharide extraction rate in the microwave extraction process were carried out. Then, using the FMTP content as a response index, central composite tests on the four factors were conducted, and an optimization analysis using the response surface method was completed. Consequently, we obtained the optimum conditions for FMTP microwave extraction: a solvent-material ratio of 30.00 mL/mg, extraction power of 700 W, extraction time of 20 min, and two extractions. The FMTP extraction rate was 15.75% at the optimum conditions, consistent with the theoretical predictions. The crude polysaccharide was further purified to obtain high-purity FMTP polysaccharide, having a weight-average molecular mass of 1288 Da. The antioxidant activities of FMTP were evaluated using the hydroxyl superoxide anion, 2,2-diphenyl-1-picrylhydrazyl (DPPH), and nitrite free radical scavenging assays and reducing power assay. The data show that FMTP has considerable antioxidant activity. Thus, polysaccharides from Fructus Meliae Toosendan could be used as a potential antioxidant agent in medicine or as a functional food.


Subject(s)
Chemical Fractionation/methods , Fruit/chemistry , Meliaceae/chemistry , Microwaves , Polysaccharides/chemistry , Polysaccharides/isolation & purification , Antioxidants/chemistry , Antioxidants/isolation & purification , Hydroxyl Radical/chemistry , Molecular Weight , Superoxides/chemistry
19.
Biochim Biophys Acta Mol Basis Dis ; 1864(9 Pt B): 2859-2870, 2018 09.
Article in English | MEDLINE | ID: mdl-29842922

ABSTRACT

Parkinson's disease (PD) is characterized by the degeneration of dopaminergic neurons in the substantia nigra compacta (SNc). Although mitochondrial dysfunction is the critical factor in the pathogenesis of PD, the underlying molecular mechanisms are not well understood, and as a result, effective medical interventions are lacking. Mitochondrial fission and fusion play important roles in the maintenance of mitochondrial function and cell viability. Here, we investigated the effects of MitoQ, a mitochondria-targeted antioxidant, in 6-hydroxydopamine (6-OHDA)-induced in vitro and in vivo PD models. We observed that 6-OHDA enhanced mitochondrial fission by decreasing the expression of Mfn1, Mfn2 and OPA1 as well as by increasing the expression of Drp1 in the dopaminergic (DA) cell line SN4741. Notably, MitoQ treatment particularly upregulated the Mfn2 protein and mRNA levels and promoted mitochondrial fusion in the presence of 6-OHDA in a Mfn2-dependent manner. In addition, MitoQ also stabilized mitochondrial morphology and function in the presence of 6-OHDA, which further suppressed the formation of reactive oxygen species (ROS), as well as ameliorated mitochondrial fragmentation and cellular apoptosis. Moreover, the activation of peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α) was attributed to the upregulation of Mfn2 induced by MitoQ. Consistent with these findings, administration of MitoQ in 6-OHDA-treated mice significantly rescued the decrease of Mfn2 expression and the loss of DA neurons in the SNc. Taken together, our findings suggest that MitoQ protects DA neurons in a 6-OHDA induced PD model by activating PGC-1α to enhance Mfn2-dependent mitochondrial fusion.


Subject(s)
Antioxidants/pharmacology , GTP Phosphohydrolases/metabolism , Mitochondrial Dynamics/drug effects , Parkinson Disease/drug therapy , Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha/metabolism , Animals , Antioxidants/therapeutic use , Cell Line , Cell Survival/drug effects , Disease Models, Animal , Dopaminergic Neurons , GTP Phosphohydrolases/genetics , Humans , Male , Mice , Mice, Inbred C57BL , Mitochondria/drug effects , Mitochondria/metabolism , Organophosphorus Compounds/pharmacology , Organophosphorus Compounds/therapeutic use , Oxidopamine/toxicity , Parkinson Disease/etiology , Parkinson Disease/pathology , Phosphorylation , RNA, Messenger/metabolism , Substantia Nigra/drug effects , Substantia Nigra/pathology , Ubiquinone/analogs & derivatives , Ubiquinone/pharmacology , Ubiquinone/therapeutic use , Up-Regulation
20.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-923743

ABSTRACT

@#Objective To optimize the ways of extubation after tracheotomy.Methods From August, 2016 to April, 2018, 118 patients after tracheotomy for brain injury were divided into early extubation group (n=74) and conventional extubation group (n=44). The success rate and tolerance of extubation were compared, and the biochemical markers of blood were tested before and seven days after extubation. The early extubation group was divided into disposable extubation group (n=37) and occlusion tube-extubation group (n=37), and their success rates of extubation were compared.Results There was no significant difference in success rate between the early extubation group and the conventional extubation group (χ2=0.016, P>0.05). The tolerance was less in the early extubation group on the first day of extubation (χ2=4.909, P<0.05), and it was not different seven days and 15 days after extubation (χ2<1.995, P>0.05). The procalcitonin, hypersensitive C reactive protein and white blood cell count decreased (t>2.680, P<0.05), and hemoglobin and albumin increased seven days after extubation (t>11.620, P<0.001). There was no significant difference in the success rate between the disposable extubation group and the occlusion tube-extubation group (χ2<2.902, P>0.05).Conclusion Satisfactory cough and deglutition reflex are the core indexes of successful extubation, other indications may not influence on the success of extubation but on tolerance. Extubation may benefit to control the complications of tracheotomy. The disposable extubation is more recommended.

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