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1.
Bull Environ Contam Toxicol ; 98(4): 478-483, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28084506

RESUMO

We evaluated the occurrence and distribution of 12 antibiotics from the sulfonamide (SAs), fluoroquinolone (FQs) and tetracycline (TCs) groups in the Weihe River, North China. The total antibiotic concentrations in surface water, pore water, and sediment samples ranged from 11.1 to 173.1 ng/L, 5.8 to 103.9 ng/L, and 9.5 to 153.4 µg/kg, respectively. The values of the sediment-water partitioning coefficient in the Weihe River varied widely, from not detected to 943, 2213, and 2405 L/kg for SAs, FQs, and TCs, respectively. The values of the partitioning coefficients between sediment and surface water were generally lower than those between sediment and pore water, which indicated ongoing inputs to the water. The risk assessment showed that there were relatively high ecological risks to aquatic algae in this area from sulfamethoxazole, norfloxacin, tetracycline, ofloxacin, and ciprofloxacin.


Assuntos
Fluoroquinolonas/análise , Sedimentos Geológicos/química , Rios/química , Sulfonamidas/análise , Tetraciclinas/análise , Antibacterianos/análise , China , Monitoramento Ambiental , Medição de Risco , Água , Poluentes Químicos da Água/análise
2.
Acta Biochim Biophys Sin (Shanghai) ; 48(5): 437-46, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27118553

RESUMO

Flavonoids have been shown to improve cognitive function and delay the dementia progression. However, the underlying mechanisms remain elusive. In the present study, we examined the effect of Scutellaria baicalensis stem-leaf total flavonoids (SSTFs) extracted from S. baicalensis Georgi on spatial learning and memory in a vascular dementia (VaD) rat model and explored its molecular mechanisms. The VaD rats were developed by permanent bilateral occlusion of the common carotid artery. Seven days after recovery, the VaD rats were treated with either 50 or 100 mg/kg of SSTF for 60 days. The spatial learning and memory was evaluated in the Morris water maze (MWM) test. The tau hyperphosphorylation and the levels of the related protein kinases or phosphatases were examined by western blot analysis. In VaD rats, SSTF treatment at 100 mg/kg significantly reduced the escape latency in training trial in MWM test. In the probe trial, SSTF treatment increased the searching time and travel distance in the target quadrant. SSTF treatment inhibited the tau phosphorylation in both cortex and hippocampus in VaD rats. Meanwhile, SSTF reduced the activity of glycogen synthase kinase 3ß and cyclin-dependent kinase 5 in VaD rats. In contrast, SSTF treatment increased the level of the protein phosphatase 2A subunit B in VaD rats. SSTF treatment significantly improved the spatial cognition in VaD rats. Our results suggest that SSTF may alleviate tau-hyperphosphorylation-induced neurotoxicity through coordinating the activity of kinases and phosphatase after a stroke. SSTF may be developed into promising novel therapeutics for VaD.


Assuntos
Demência Vascular/tratamento farmacológico , Flavonoides/farmacologia , Memória/efeitos dos fármacos , Scutellaria baicalensis , Aprendizagem Espacial/efeitos dos fármacos , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Isquemia Encefálica/complicações , Quinase 5 Dependente de Ciclina/metabolismo , Demência Vascular/etiologia , Demência Vascular/psicologia , Medicamentos de Ervas Chinesas/farmacologia , Glicogênio Sintase Quinase 3 beta/metabolismo , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Proteína Fosfatase 2/metabolismo , Ratos , Ratos Sprague-Dawley , Proteínas tau/metabolismo
3.
Med Sci Monit ; 20: 1129-36, 2014 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-24990175

RESUMO

BACKGROUND: We aimed to investigate cognitive function and affective disorder in elderly patients with symptomatic vertebrobasilar artery stenosis (SVAS) after stent-assisted angioplasty (SAA) and to explore the potential mechanism. MATERIAL AND METHODS: The study subjects were 26 elderly SVAS patients who were non-responsive to pharmacotherapy and received SAA (study group) and 30 patients receiving intracoronary stent implantation (control group). Montreal cognitive assessment (MoCA), Hamilton depression rating scale (HAMD), and Hamilton anxiety rating scale (HAMA) were used. RESULTS: The total MoCA score, scores of line connection, copying cube, drawing clock, and delayed recall increased significantly in the study group after surgery (P<0.05, P<0.01). In addition, the MoCA score increased over time and the total MoCA score at 12 months was markedly higher than that at 1 month (P<0.05). The scores of HAMD and HAMA decreased dramatically after surgery compared with before surgery in these patients (P<0.01). A comparison at the corresponding period was performed between study group and control group, and it was found that the differences in total MoCA scores and scores of line connection, copying cube, drawing clock, and delayed recall before surgery and at 1 month after surgery were significant (P<0.05, P<0.01). CONCLUSIONS: SAA may improve the visuospatial/executive abilities and delayed recall, as well as the depression and anxiety in patients with SVAS. Larger and controlled trails are needed to investigate the effect of SAA on cognition and affection in these patients.


Assuntos
Angioplastia , Arteriopatias Oclusivas/terapia , Artéria Basilar/fisiopatologia , Cognição/fisiologia , Transtornos do Humor/fisiopatologia , Stents , Artéria Vertebral/fisiopatologia , Idoso , Angioplastia/efeitos adversos , Arteriopatias Oclusivas/fisiopatologia , Artéria Basilar/patologia , Velocidade do Fluxo Sanguíneo , Estudos de Casos e Controles , Constrição Patológica , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Complicações Pós-Operatórias/etiologia , Recidiva , Fluxo Sanguíneo Regional , Stents/efeitos adversos , Acidente Vascular Cerebral/etiologia , Artéria Vertebral/patologia
4.
Med Sci Monit ; 20: 1461-8, 2014 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-25129549

RESUMO

BACKGROUND: The aim of this study was to investigate the influence of carotid artery stenting (CAS) on the cognition and quality of life of elderly patients with severe stenosis of the internal carotid artery. MATERIAL/METHODS: 65 elderly patients with symptomatic severe stenosis of internal carotid artery were recruited into 2 groups: the pharmacotherapy group (n=29) and the CAS group (n=36). Before surgery and 1, 3, 6, and 12 months after surgery, Montreal cognitive assessment (MoCA) was used for the evaluation of cognition and WHOQOL-BREF was used for the assessment of quality of life. RESULTS: At 12 months after surgery, total MoCA score and WHOQOL-BREF score in the pharmacotherapy group was significantly reduced when compared with those before surgery (P<0.05). In the CAS group, the total MoCA score, scores of attention and delayed recall, and WHOQOL-BREF score increased significantly at different time points after surgery when compared with those before surgery (P<0.05). Moreover, in CAS group, the MoCA score and WHOQOL-BREF markedly increased gradually over time (P<0.05). Compared with the pharmacotherapy group, cognition and quality of life in the CAS group were improved dramatically during the follow-up period (P<0.05). CONCLUSIONS: Severe stenosis of the internal carotid artery is a cause of cognition impairment, and CAS may improve cognition and quality of life.


Assuntos
Angioplastia/efeitos adversos , Estenose das Carótidas/tratamento farmacológico , Estenose das Carótidas/cirurgia , Cognição/fisiologia , Qualidade de Vida/psicologia , Stents , Idoso , Análise de Variância , Aspirina/uso terapêutico , Atorvastatina , China , Clopidogrel , Feminino , Ácidos Heptanoicos/uso terapêutico , Humanos , Masculino , Pirróis/uso terapêutico , Fluxo Sanguíneo Regional/fisiologia , Ticlopidina/análogos & derivados , Ticlopidina/uso terapêutico , Resultado do Tratamento , Ultrassonografia Doppler Transcraniana
5.
Probiotics Antimicrob Proteins ; 16(2): 606-622, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37040014

RESUMO

Probiotics have been reported to influence the gut microbiota and immune system in various diseases. Now, the potential impacts of probiotics on tumor treatment still need to be investigated. In this study, three strains of probiotics, Bifidobacterium breve BBr60 (BBr60), Pediococcus pentosaceus PP06 (PP06), and Bifidobacterium longum subsp. longum BL21 (BL21) were investigated for their combination with chemotherapeutic drugs doxorubicin (DOX). Our study showed that PP06 and BL21 have good performance in gastric acid, bile salt, and intestinal fluid tolerance, antimicrobial activity to pathogenic Staphylococcus aureus, and adhesion to Caco-2 cells. Besides, the probiotics all exhibited antioxidant effect, especially BL21. In vitro cytotoxicity and in vivo animal studies revealed that probiotics used alone could not directly induce anti-tumor effects, but the combination of PP06/BL21 and DOX exhibits a higher inhibition rate than DOX alone, via recruitment and infiltration of immune cells in the tumor region. After 16S rRNA analysis of fecal samples from animal models, it was found that BL21 could increase the abundance of Akkermansia, which may also play a role in regulating the tumor microenvironment to improve immune response. In conclusion, BL21 and PP06 in this study could enhance the anti-tumor efficacy by influencing the gut microbiota and tumor immune microenvironment.


Assuntos
Bifidobacterium , Microbioma Gastrointestinal , Probióticos , Humanos , Animais , Células CACO-2 , Microambiente Tumoral , RNA Ribossômico 16S/genética , Probióticos/farmacologia
6.
Front Microbiol ; 14: 1211831, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37378287

RESUMO

Introduction: Currently, hyperuricemia has shown a surprisingly rising trend, which attracts widespread attention due to potentially major health risks. Considering the inevitable side effects of long-term medicine, probiotics are emerging as potential therapeutics due to their ability to improve uric acid metabolism and superior safety. Methods: In our study, two strains of probiotics, Lactobacillus gasseri LG08 (LG08) and Leuconostoc mesenteroides LM58 (LM58) isolated from kimchi were evaluated for the prebiotic properties in vitro and uric-lowering effects in vivo. Here, hyperuricemia animal model and 16S rRNA gene amplicons analysis were further studied to investigate whether these probiotics exert different effects in prevention and treatment. Results: In vivo indicators and intestinal flora immunity revealed that both LG08 and LM58 significantly prevent the development and progression of hyperuricemia, repair the antioxidant system and maintain intestinal flora balance in healthy rats, especially LM58. After hyperuricemia was formed, although the effect of LG08 and LM58 could decrease the level of uric acid, the effect to reverse and repair antioxidant levels in the body was limited. Discussion: In our study, these findings have important implications for hyperuricemia prevention and therapy, and provided more mechanistic insights into the effect of probiotics in hyperuricemia.

7.
Zhongguo Zhong Yao Za Zhi ; 37(23): 3667-8, 2012 Dec.
Artigo em Zh | MEDLINE | ID: mdl-23477161

RESUMO

OBJECTIVE: To observe the clinical efficacy of Maixuekang capsule in reconvalescents of cerebral infarction and its impact on coagulation function. METHOD: One hundred and twenty cases of reconvalescents of cerebral infarction were randomly divided into treatment and control groups. The 50 cases in the control group were provided with conventional therapy, while the 70 cases in the treatment group were provided with the combination of conventional therapy and Maixuekang capsule for 3 months. Their neurological function and prothrombin time (PT), activated partial thromboplastin time (APTT) clotting enzyme time (TT), fibrinogen (Fib) were measured before and after treatment. RESULT: After the treatment, PT, APTT and TT were prolonged compared with those before the treatment in the treatment group (P<0.05), whereas Fib, neurological deficit scores decreased (P<0.01) and significantly different from the control group (P<0.05). CONCLUSION: Maixuekang capsule is among safe and effective drugs in treatment of reconvalescents of cerebral infarction, and can improve the patient's coagulation state.


Assuntos
Infarto Cerebral/tratamento farmacológico , Medicamentos de Ervas Chinesas/administração & dosagem , Idoso , Coagulação Sanguínea/efeitos dos fármacos , Cápsulas/uso terapêutico , Infarto Cerebral/metabolismo , Infarto Cerebral/fisiopatologia , Medicamentos de Ervas Chinesas/efeitos adversos , Feminino , Fibrinogênio/metabolismo , Humanos , Masculino , Tempo de Protrombina
8.
Curr Oncol ; 29(10): 7868-7886, 2022 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-36290899

RESUMO

Boron neutron capture therapy (BNCT) is a binary modality that is used to treat a variety of malignancies, using neutrons to irradiate boron-10 (10B) nuclei that have entered tumor cells to produce highly linear energy transfer (LET) alpha particles and recoil 7Li nuclei (10B [n, α] 7Li). Therefore, the most important part in BNCT is to selectively deliver a large number of 10B to tumor cells and only a small amount to normal tissue. So far, BNCT has been used in more than 2000 cases worldwide, and the efficacy of BNCT in the treatment of head and neck cancer, malignant meningioma, melanoma and hepatocellular carcinoma has been confirmed. We collected and collated clinical studies of second-generation boron delivery agents. The combination of different drugs, the mode of administration, and the combination of multiple treatments have an important impact on patient survival. We summarized the critical issues that must be addressed, with the hope that the next generation of boron delivery agents will overcome these challenges.


Assuntos
Terapia por Captura de Nêutron de Boro , Neoplasias Encefálicas , Neoplasias de Cabeça e Pescoço , Melanoma , Humanos , Boro
9.
Rev Sci Instrum ; 93(9): 095005, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36182506

RESUMO

Neutral Beam Injection (NBI) is one of the four efficient ways of assistant heating on the Experimental Advanced Superconducting Tokamak (EAST) device. Measures have been taken to ensure more reliable monitoring of NBI components' thermal data. Infrared thermometers, unlike surface-mounted thermocouples, have the advantage of non-contact and thus will not cause interference and get far less chance of malfunctioning [Childs et al., Rev Sci. Instruments 71, 2959-2978 (2000)]. In this paper, the remote infrared temperature measurement with optical fiber is reported to meet the requirement of the EAST-NBI diagnostic system. Some tests have been conducted on the remote infrared temperature measurement under the working condition, and an atmospheric propagation simulation was performed to estimate the atmosphere absorption. The results indicate that the detector's response is in line with the theory, and the atmosphere absorption within a certain wavelength should not be ignored. Temperature measurement error is within one percent at temperatures above 200 °C. So, for the temperature range of 200-600 °C, the remote infrared temperature measurement by the optical fiber can fully meet its expectation.

10.
Sci Data ; 9(1): 467, 2022 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-35918351

RESUMO

Mentorship in science is crucial for topic choice, career decisions, and the success of mentees and mentors. Typically, researchers who study mentorship use article co-authorship and doctoral dissertation datasets. However, available datasets of this type focus on narrow selections of fields and miss out on early career and non-publication-related interactions. Here, we describe Mentorship, a crowdsourced dataset of 743176 mentorship relationships among 738989 scientists primarily in biosciences that avoids these shortcomings. Our dataset enriches the Academic Family Tree project by adding publication data from the Microsoft Academic Graph and "semantic" representations of research using deep learning content analysis. Because gender and race have become critical dimensions when analyzing mentorship and disparities in science, we also provide estimations of these factors. We perform extensive validations of the profile-publication matching, semantic content, and demographic inferences, which mostly cover neuroscience and biomedical sciences. We anticipate this dataset will spur the study of mentorship in science and deepen our understanding of its role in scientists' career outcomes.


Assuntos
Disciplinas das Ciências Biológicas , Mentores , Pesquisadores , Demografia , Humanos
11.
Int J Nanomedicine ; 16: 8069-8086, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34934313

RESUMO

Bacteria and their derivatives (membrane vesicles, MVs) exhibit great advantages for targeting hypoxic tumor cores, strong penetration ability and activating immune responses, holding great potential as auspicious candidates for therapeutic and drug-delivery applications. However, the safety issues and low therapeutic efficiency by single administration still need to be solved. To further optimize their performance and to utilize their natural abilities, scientists have strived to modify bacteria with new moieties on their surface while preserving their advantages. The aim of this review is to give a comprehensive overview of a non-genetic engineering modification strategy that can be used to optimize the bacteria with nanomaterials and the design strategy that can be used to optimize MVs for better targeted therapy. Here, the advantages and disadvantages of these processes and their applicability for the development of bacteria-related delivery system as antitumor therapeutic agents are discussed. The prospect and the challenges of the above targeted delivery system are also proposed.


Assuntos
Antineoplásicos , Neoplasias , Antineoplásicos/uso terapêutico , Bactérias , Sistemas de Liberação de Medicamentos , Humanos , Nanotecnologia , Neoplasias/tratamento farmacológico
12.
Ann Palliat Med ; 10(10): 10591-10599, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34763506

RESUMO

BACKGROUND: During the epidemic, the mental health of college students was generally poor, especially anxiety and depression, which should be treated using counseling and intervention. This study aimed to observe the influence of dialectical behavior therapy on the anxiety and depression of medical students during the normalization of the prevention and control of the COVID-19 epidemic. METHODS: A total of 26 medical students (experimental group) were treated with dialectical behavior therapy intervention for 4 weeks. Changes in depression, anxiety, and stress levels were assessed by the Patient Health Questionnaire (PHQ-9), the Generalized Anxiety Disorder (GAD-7) scale, the Somatic Self-rating Scale (SSS), and the Perceived Stress Scale (PSS-10). This group was compared with 26 medical students (control group) without intervention. RESULTS: The value-added scores of the PHQ-9 (t=2.543, P=0.014) and GAD-7 scales (t=3.790, P=0.000) in the experimental group were significantly higher than those in the control group, while in the SSS scale, the value-added score of the depressive symptoms subscale (t=2.234, P=0.030) in the experimental group was significantly higher than that of the control group. For the total score of the PSS-10 scale (t=2.435, P=0.018), the value-added score of the experimental group was significantly higher than that of the control group. CONCLUSIONS: The intervention of dialectical behavior therapy can effectively alleviate the depression and anxiety of medical students during the normalization of epidemic prevention and control. TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiCTR2100048784.


Assuntos
COVID-19 , Terapia do Comportamento Dialético , Epidemias , Psicoterapia de Grupo , Estudantes de Medicina , Ansiedade/prevenção & controle , Transtornos de Ansiedade/prevenção & controle , Humanos , SARS-CoV-2
13.
Rev Sci Instrum ; 91(4): 043501, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32357727

RESUMO

In order to study the generation and extraction of negative ions for neutral beam injection application, a prototype radio frequency driven negative ion source and the corresponding test bench are under construction at the Institute of Plasma Physics, Chinese Academy of Sciences. A new design of infrared radiation diagnostic calorimeter for testing beam characteristics is put forward. Compared with the conventional calorimeter, the calorimeter adopts the block structure (8 × 28 tungsten hexahedron blocks) and modularization design (4 modules), so it has higher precision and good scalability. The thermal performance of the calorimeter is assessed using a finite element method. Simulation results show that the design can be achieved to operate in the stable-state mode at the maximum thermal flux 6.45 MW/m2 and meet the full requirement of beam diagnosis.

14.
Rev Sci Instrum ; 90(12): 123509, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31893840

RESUMO

Negative ion source is a core part of the neutral beam injection system for magnetic confinement fusion devices. The density of produced hydrogen negative ions is a critical parameter of the negative ion source. Cavity ring-down spectroscopy (CRDS) is an ultrasensitive absorption diagnostic technique for density measurement. Based on the photodetachment process, CRDS can measure the integrated line-of-sight hydrogen negative ion density in a high power ion source. The CRDS diagnostic system has been applied to Hefei utility negative ion test equipment with the radio frequency (RF) source, which is now one of the references for the China Fusion Engineering Test Reactor neutral beam injection system. Typical ring-down signals are obtained to calculate the density of hydrogen negative ions. The time evolution of hydrogen negative ion density is successfully measured. Preliminary experiments show the accurate relationship between RF power and measured hydrogen negative ion density.

15.
Rev Sci Instrum ; 90(11): 113313, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31779404

RESUMO

A research project of the China Fusion Engineering Test Reactor (CFETR) Negative ion-based Neutral Beam Injection (NNBI) prototype has been started in China. The objectives of the CFETR NNBI prototype are to produce a negative hydrogen ion beam of >20 A up to 400 keV for 3600 s and to attain a neutralization efficiency of >50%. In order to identify and optimize the design of the negative ion accelerator, a self-consistent model has been developed to consider all key physics and engineering issues (electric and magnetic fields, background gas flow, beam optics, beam-gas interaction, secondary particle trajectories, power deposition on grids, heat removal design, and mounting pattern). This paper presents the primary results by applying the self-consistent model to the current design of the 400 keV H- accelerator of the CFETR NNBI prototype.

16.
Rev Sci Instrum ; 90(12): 123512, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31893825

RESUMO

According to the latest physics design of the China Fusion Engineering Test Reactor (CFETR), two neutral beam injectors (NBIs), which deliver a total of 40 MW in not less than 3600 s with 1 MeV D0, are demanded to support current drive and plasma rotation. To minimize the risks and time to provide the CFETR with reliable NBIs, a negative NBI test facility will be developed at the Institute of Plasma Physics, Chinese Academy of Science. Its mission is to understand the characteristics of the RF driven ion source and negative ion generation and extraction and to improve RF efficiency and beam quality. In order to achieve this goal, a set of diagnostic tools will be used in this test facility. For source diagnostics, optical emission spectroscopy, cavity ring-down spectroscopy, laser absorption spectroscopy, and electrostatic probes are planned to be used. Beam emission spectroscopy, W-wire calorimeters, 1D carbon fiber composite diagnostic calorimeters, beam dump with thermocouples, and water-flow calorimetry are used to assess the beam properties. The design of the diagnostic system is presented.

17.
Rev Sci Instrum ; 90(11): 113315, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31779416

RESUMO

A negative ion source acts as a critical part in a neutral beam injector (NBI). A high current ion source is required for the high-power NBI. In this paper, a prototype radio frequency (RF) ion source and its test facility are developed in the Institute of Plasma Physics, Chinese Academy of Sciences, to demonstrate the key technology of the high power negative ion source. The structure design of the RF negative ion source is presented, involving the designs of the ion source plasma generator and accelerator. The detailed structure design and analysis of the key parts of the ion source are also presented, such as the Faraday shield (FS) and accelerator grids. The fluid-thermal-structural coupling characteristics of the FS and grid are explored with different mechanisms of fluid pressure, RF power, and the structure type on the thermal stress. Then, the processing and manufacturing scheme of the FS and grids are also given. Finally, the results were presented with a manufactured three cooling channel FS. The experimental results prove that the developed structure design of the RF ion source is effective and reliable, and the correctness of finite element analysis is also verified by experimental data comparison.

18.
Rev Sci Instrum ; 90(11): 115117, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31779419

RESUMO

For a prestudy of the key science and technology of the RF negative ion source for fusion application, a negative RF ion source test facility was developed at the Institute of Plasma Physics, Chinese Academy of Science (ASIPP). The magnetic filter field in front of the extraction system plays an important role in reducing the loss of negative hydrogen ions and inhibiting coextraction of electrons. The existing filter field of the prototype ion source is generated by permanent magnets arranged on both sides of the expansion chamber; the gradient and the uniformity of the field are poor, resulting in a large plasma distribution unevenness in the experiment. In order to reduce the B→×∇B drift and the beam deflection, the plasma nonuniformity, and the beam alignment, its gradient should be as low as possible, especially near the Plasma Grid (PG), while its strength should be as low as possible inside both the driver and the extraction region. Hence, the magnetic filter field generated by the permanent magnet and the PG current with return wires is proposed. A finite element analysis method is used to calculate the distribution of the magnetic field throughout the ion source, especially the filter profile along the centerline perpendicular to the PG and the section parallel to the PG. Several cases were compared and the final design provides a more uniform magnetic field in the region within 70 mm above the plasma grid, while the field strength is around 5 mT and the integral BdL quantity is greater than 1.2 mTm.

19.
Rev Sci Instrum ; 90(11): 113319, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31779444

RESUMO

Neutral beam injection (NBI) is one of the most effective tools of four auxiliary plasma heating methods for fusion plasma heating and current drive. Now, a next generation fusion device, China Fusion Engineering Test Reactor, is under design, and a large negative NBI is foreseen. In order to demonstrate the key technology and performance of a negative ion source, a negative radio frequency (RF) ion source test facility has been developed since 2017 in the Institute of Plasma Physics, Chinese Academy of Science. A prototype RF ion source with double drivers (having the same structure with an inner diameter of 200 mm) was developed and tested on the test facility to preresearch the key technology of the RF plasma generator. The driver is equipped with a water-cooled Faraday shield to protect the alumina cylinder from the plasma, and the plasma expands into the rectangular expansion chamber. The RF power of 100 kW with a frequency of 1 MHz is transferred to the RF driver by a matching unit. The characteristics of plasma discharge were studied with classical diagnostic tools, such as the Langmuir probe and water flow calorimeter. Based on the plasma performance tests, a high power of 82 kW plasma discharge for a long pulse of 1000 s was achieved. In this paper, the details of the ion source design, characteristics of plasma, and future research plan will be presented.

20.
Biomed Pharmacother ; 102: 86-93, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29549732

RESUMO

PURPOSE: To investigate the protective effects of miR-320 on cerebral ischemia/reperfusion (I/R) injury in mice and PC12 cells. METHODS: miR-320 normal control (NC), inhibitor fragment and overexpression fragments were injected into mice lateral ventricles. Thereafter, the middle cerebral artery occlusion (MCAO) for left cerebrum method was employed in order to establish a cerebral I/R injury mice model. Apoptosis in the peripheral region of cerebral infarction and the volume of cerebral infarction and brain edema were tested as well. For simulating MCAO in vitro, the PC12 cells were subjected to oxygen-glucose deprivation. The lentivirus transfection technique was used to overexpress or inhibit miR-320. Furthermore, the effects of miR-320 on the survival and apoptosis of PC12 were monitored by MTT and TUNEL detection. RESULTS: A cerebral I/R injury mice model was successfully established. MiR-320 enhanced cell apoptosis of the injury side cortical infarcted peripheral zone and increased brain infarction volume and edema volume in MCAO/R mice. In addition, Insulin growth factor-1 (IGF-1) mRNA and protein expressions in MCAO/R mice were inhibited by miR-320 as well. Moreover, the results of cell studies were consist with the animal studies. CONCLUSIONS: miR-320 may be involved in the regulation of cerebral I/R for brain parenchyma injury by inhibition of IGF-1 pathway.


Assuntos
Isquemia Encefálica/patologia , Fator de Crescimento Insulin-Like I/metabolismo , MicroRNAs/genética , Traumatismo por Reperfusão/patologia , Animais , Apoptose/genética , Encéfalo/patologia , Edema Encefálico/genética , Isquemia Encefálica/genética , Infarto Cerebral/genética , Modelos Animais de Doenças , Glucose/metabolismo , Marcação In Situ das Extremidades Cortadas , Infarto da Artéria Cerebral Média/complicações , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Oxigênio/metabolismo , Células PC12 , Ratos , Traumatismo por Reperfusão/genética
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