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1.
Rev Sci Instrum ; 95(8)2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39185928

RESUMO

The Laser Blow-Off (LBO) impurity injection system is a crucial tool for studying impurity transport and plasma behavior. Conducting proactive impurity transport research is challenging on experimental advanced superconducting tokamak (EAST) due to the uncontrollable generation of impurity sources; therefore, it is necessary to develop a laser blow-off impurity injection system for injecting controlled trace impurity particles. This study presents the design and test results of an LBO system for the EAST. The system aims to provide precise and repeatable control over the timing and quantity of impurity injection. The system primarily consists of a laser source, two mirrors, a moveable focusing lens, a target material, and a vacuum system. The movement of the focusing lens is achieved by a three-dimensional displacement system. The operation of the system is completed by a remote control system. With the accurate control system, the laser spot diameter is adjustable, allowing for modification of impurity injection quantity. The test results demonstrate that the system can rapidly detect external trigger signals and ensure precise timing for the impurity injection. Furthermore, this system can also quickly change the focal point of the laser spot, addressing the requirements for impurity injections during the experiments with less than 0.4 mm position error for laser spot focusing. Test results have shown that the aluminum film material can be peeled off by the LBO system when the laser energy exceeds 650 mJ and the smallest ablation spot is about 1 mm. This study is of significant importance for conducting plasma impurity transport research on the EAST.

2.
Rev Sci Instrum ; 95(8)2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39207188

RESUMO

Electron Beam Ion Traps (EBITs) serve as efficient tools for producing and studying highly charged ions. In response to the diagnostic requirements of upcoming magnetic confinement fusion devices, a medium-energy atomic spectra research platform based on a compact EBIT is developed. This platform achieves a central magnetic field of up to 1.0 T, with electron beam currents reaching 20 mA and electron energies up to 30 keV, similar to the electron temperature on fusion reactors. The developed atomic spectra platform successfully provided spectral data for elements such as argon, xenon, iron, and tungsten. This platform stands as a valuable asset for advancing research in nuclear fusion, particularly concerning impurity spectroscopic diagnostics.

3.
Rev Sci Instrum ; 95(7)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-39028911

RESUMO

A space-resolved vacuum ultraviolet spectroscopy is employed to measure impurity emission profiles (500-3200 Å) on EAST. This study successfully captures C IV (1548.20 and 1550.77 Å) lines emitted from carbon ions and derives ion temperatures using Doppler broadening and a collision model based on their intensity ratios. Both the emission intensity and ion temperature profiles are determined. However, the calculated results reveal a lower temperature of around 10-20 eV with the collision model, suggesting a potential need for further correction in subsequent calculations. Furthermore, this study explores relative rotation velocities from the Doppler shift, indicating an increase in toroidal rotation velocity with applied neutral beam injection. The measured results exhibit concordance with the charge exchange recombination spectrometer data. Furthermore, during boron powder dropping discharges on EAST, B II (1623.60, 1623.79, 1623.95, 1624.02, 1624.17, and 1624.38 Å) emission lines exhibiting a similar time behavior trend with boron powder injection are identified. Ion temperatures are measured using B II (1362.46 Å) through the Doppler broadening method. These techniques hold significant promise for future impurity analysis at the edge of EAST, providing valuable insights into the behavior of carbon and boron ions.

4.
Neoplasma ; 642017 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-28485167

RESUMO

This article has been withdrawn at the request authors.

5.
Clin Rheumatol ; 36(5): 1023-1029, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28342151

RESUMO

This study aims to assess the risk factors of cardiovascular disease (CVD) and to determine the association of traditional and biologic disease-modifying anti-rheumatic drugs (DMARDs) with risk for CVD in Chinese rheumatoid arthritis (RA) patients. A cross-sectional cohort of 2013 RA patients from 21 hospitals around China was established. Medical history of CVD was documented. The patients' social background, clinical manifestations, comorbidities, and medications were also collected. Of the 2013 patients, 256 had CVD with an incidence of 12.7%. Compared with non-CVD controls, RA patients with CVD had a significantly advanced age, long-standing median disease duration, more often male and more deformity joints. Patients with CVD also had higher rates of smoking, rheumatoid nodules, interstitial lung disease, and anemia. The prevalence of comorbidities, including hypothyroidism, diabetes mellitus (DM), hypertension, and hyperlipidemia, was also significant higher in the CVD group. In contrast, patients treated with methotrexate, hydroxychloroquine (HCQ), and TNF blockers had lower incidence of CVD. The multivariate analysis showed that the use of HCQ was a protective factor of CVD, while hypertension, hyperlipidemia, and interstitial lung disease were independent risk factors of CVD. Our study shows that the independent risk factors of CVD include hypertension, hyperlipidemia, and interstitial lung disease. HCQ reduces the risk of CVD in patients with RA.


Assuntos
Antirreumáticos/uso terapêutico , Artrite Reumatoide/complicações , Doenças Cardiovasculares/epidemiologia , Vigilância da População/métodos , Medição de Risco , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/epidemiologia , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/prevenção & controle , Criança , China/epidemiologia , Estudos Transversais , Progressão da Doença , Feminino , Seguimentos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Fatores de Risco , Adulto Jovem
6.
Genet Mol Res ; 14(1): 2162-75, 2015 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-25867364

RESUMO

The present study aims to purify and characterize lectin from tartary buckwheat seeds and study its properties as well as biological activities to determine its possible biomedical applications in promoting maturation and proliferation of peripheral blood DCs derived from healthy donors and to study the effect of inducing apoptosis in human leukemia U937 cells. A novel tartary buckwheat lectin (TBL) protein, purified from tartary buckwheat seeds, showed a single band with a molecular mass of 65 kDa in SDS-PAGE. The purified TBL hemagglutinated both human and animal erythrocytes and showed preference for blood type O and the rabbit blood type. TBL is active at up to 60°C, and it is acid- and alkali-stable. TBL (25 µg/mL) combined with 5 x 10(-5) M rhIL-4 promotes maturation and proliferation of peripheral blood dendritic cells (DCs), which is stronger than that promoted by rhTNF-α (20 ng/mL). Exposure of DCs to 50 µg/mL TBL for 48 h resulted in extensive upregulation of maturation markers CD83 and CD40. These TBL-DCs were capable of producing several pro-inflammatory cytokines such as interleukin-10 (IL-10) and interleukin-12 (IL-12). The results of the treatment of human leukemia U937 cells with TBL in doses of 12.5, 25, 50, and 100 µg/mL showed that tartary buckwheat-derived lectin induces apoptosis in a dose-dependent manner. Our results encourage the use of tartary buckwheat and tartary buckwheat-derived lectins as immunopotentiating foods, targeted to strengthen immune responses and display a potential dietary supplement for cancer prevention.


Assuntos
Células Dendríticas/efeitos dos fármacos , Fagopyrum/química , Linfoma/patologia , Lectinas de Plantas/química , Lectinas de Plantas/farmacologia , Animais , Apoptose/efeitos dos fármacos , Citocinas/farmacologia , Células Dendríticas/patologia , Humanos , Camundongos , Lectinas de Plantas/isolamento & purificação , Coelhos , Ratos , Sementes/química , Células U937
7.
Clin Exp Dermatol ; 40(6): 672-81, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25787854

RESUMO

BACKGROUND: Human placenta extract (HPE) has been used to alleviate tiredness and promote wound healing, and for its antiageing functions; however, it has not yet been studied for its effects on hair growth. In the present study, we evaluated the in vitro effect of HPE on hair growth by observing its actions on human dermal papilla cells (DPCs). AIM: To define how HPE promotes induction of anagen hair growth during the telogen phase, and to understand the synergistic molecular mechanisms of HPE and minoxidil (MXD) actions on hair growth. METHODS: We examined the effects of HPE and MXD on C57BL6/J mice using haematoxylin and eosin staining, quantitative histomorphometry, hair growth scoring, immunohistochemistry and immunofluorescence on the dorsal skins of C57BL/6J mice. RESULTS: We found that HPE synergistically augmented the effects of MXD, a promoter of hair growth. In particular, histomorphometric analysis data indicated that subcutaneous injection of HPE induced an earlier anagen phase and prolonged the anagen phase. It also stimulated increases in both the number and size of hair follicles in groups treated with HPE alone and HPE + MXD. CONCLUSIONS: From our data, we conclude that HPE increases ß-catenin and Wnt3a expression levels. Overall, our findings suggest that HPE in combination with MXD has hair growth-promoting activity and is a potential novel therapeutic treatment for alopecia or baldness in humans.


Assuntos
Cabelo/efeitos dos fármacos , Minoxidil/farmacologia , Extratos Placentários/farmacologia , Vasodilatadores/farmacologia , Alopecia/tratamento farmacológico , Análise de Variância , Animais , Proliferação de Células/efeitos dos fármacos , Derme/citologia , Sinergismo Farmacológico , Feminino , Cabelo/crescimento & desenvolvimento , Folículo Piloso/efeitos dos fármacos , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Modelos Animais , beta Catenina/metabolismo
8.
Neuroscience ; 242: 28-38, 2013 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-23523945

RESUMO

We have investigated the effect of IMM-H004 (7-hydroxy-5-methoxy-4-methyl-3-(4-methylpiperazin-1-yl)-2H-chromen-2-one), a coumarin derivative, on the amyloid beta (Aß)-induced neurotoxicity in primary culture cortical neurons and pheochromocytoma (PC12) cells. Our results showed that treatment with IMM-H004 markedly reduced the number of apoptotic cells after exposure to Aß25-35 or Aß1-42, determined by MTT, TUNEL staining and Flow cytometry. Further study indicated that IMM-H004 significantly inhibited Aß-induced cytotoxicity and apoptosis by reversing Aß-induced mitochondrial dysfunction, including MMP (mitochondrial membrane potential) decrease, reactive oxygen species production, and mitochondrial release of cytochrome c. IMM-H004 can regulate the interaction between Bax and Bcl-2, decreased levels of p53 and active caspase-3 protein induced by Aß25-35. Furthermore, IMM-H004 also reduced translocation of AIF (apoptosis-inducing factor) induced by Aß25-35. These results demonstrated that IMM-H004 was capable of protecting neuronal cells from Aß-induced degeneration through a mitochondrial-dependent apoptotic pathway. The results of this study lend further credence to the notion that IMM-H004 is a 'multipotent therapeutic agrent' that reduces toxic levels of brain Aß, and holds the potential to protect neuronal mitochondrial function in Alzheimer's disease.


Assuntos
Peptídeos beta-Amiloides/antagonistas & inibidores , Peptídeos beta-Amiloides/toxicidade , Cumarínicos/química , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Animais , Apoptose/efeitos dos fármacos , Fator de Indução de Apoptose/metabolismo , Citocromos c/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/patologia , Células PC12 , Cultura Primária de Células , Ratos , Espécies Reativas de Oxigênio/metabolismo
9.
Mol Ecol Resour ; 9(5): 1375-9, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21564911

RESUMO

This article documents the addition of 283 microsatellite marker loci to the Molecular Ecology Resources Database. Loci were developed for the following species: Agalinis acuta; Ambrosia artemisiifolia; Berula erecta; Casuarius casuarius; Cercospora zeae-maydis; Chorthippus parallelus; Conyza canadensis; Cotesia sesamiae; Epinephelus acanthistius; Ficedula hypoleuca; Grindelia hirsutula; Guadua angustifolia; Leucadendron rubrum; Maritrema novaezealandensis; Meretrix meretrix; Nilaparvata lugens; Oxyeleotris marmoratus; Phoxinus neogaeus; Pristomyrmex punctatus; Pseudobagrus brevicorpus; Seiridium cardinale; Stenopsyche marmorata; Tetranychus evansi and Xerus inauris. These loci were cross-tested on the following species: Agalinis decemloba; Agalinis tenella; Agalinis obtusifolia; Agalinis setacea; Agalinis skinneriana; Cercospora zeina; Cercospora kikuchii; Cercospora sorghi; Mycosphaerella graminicola; Setosphaeria turcica; Magnaporthe oryzae; Cotesia flavipes; Cotesia marginiventris; Grindelia Xpaludosa; Grindelia chiloensis; Grindelia fastigiata; Grindelia lanceolata; Grindelia squarrosa; Leucadendron coniferum; Leucadendron salicifolium; Leucadendron tinctum; Leucadendron meridianum; Laodelphax striatellus; Sogatella furcifera; Phoxinus eos; Phoxinus rigidus; Phoxinus brevispinosus; Phoxinus bicolor; Tetranychus urticae; Tetranychus turkestani; Tetranychus ludeni; Tetranychus neocaledonicus; Tetranychus amicus; Amphitetranychus viennensis; Eotetranychus rubiphilus; Eotetranychus tiliarium; Oligonychus perseae; Panonychus citri; Bryobia rubrioculus; Schizonobia bundi; Petrobia harti; Xerus princeps; Spermophilus tridecemlineatus and Sciurus carolinensis.

10.
J Nanosci Nanotechnol ; 8(9): 4698-701, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19049088

RESUMO

Vertically well-aligned high quality ZnO nanowires were grown on GaN epilayer on c-plane sapphire via a vapor-liquid-solid (VLS) process by introducing an Au thin film (3 nm) as a catalyst. ZnO single nanowire device was ingenuously fabricated by combining conventional optical lithography and high resolution electron beam lithography and its current-voltage characteristics were measured with doing the post process to acquire reproducible performance as a chemical gas sensor. And its temperature dependent current-voltage characteristics were measured to investigate temperature dependant electrical transport. The ZnO nanowire device showed slightly non-ohmic current-voltage characteristics which may be due to back-to-back configuration of the diodes with the insulating contact barriers and showed an relatively small activation energy of 0.2 eV. To test our device as a chemical sensor, the NO2 gas response was reported at the elevated temperature.


Assuntos
Técnicas Biossensoriais/instrumentação , Nanotecnologia/instrumentação , Nanofios/química , Óxido de Zinco/química , Cristalização , Eletricidade , Eletroquímica/métodos , Microscopia Eletrônica de Varredura , Modelos Químicos , Nanotubos/química , Óptica e Fotônica , Semicondutores , Temperatura , Difração de Raios X , Zinco/química
11.
J Cell Biochem ; 46(2): 125-33, 1991 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1918178

RESUMO

To elucidate the relationship between epidermal growth factor (EGF)/transforming growth factor (TGF-alpha) and estradiol-17 beta (E) in cell proliferation, we examined their effects on the breast cancer cell line, CAMA-1. While E was able to consistently induce cell proliferation under a variety of experimental conditions, EGF/TGF-alpha was without effect. Despite the presence of the receptor (EGFR) gene, mature EGFR protein and mRNA were not detected by radioreceptor assay, 35S Met-labelling, and the Intron Differential RNA/PCR method under conditions in which cells remain responsive to E. Furthermore, TGF-alpha is not an autocrine factor in CAMA-1 cells. We demonstrated unequivocally that EGF/TGF-alpha interaction with EGFR is not an obligatory event in mediating estrogen-stimulated cell proliferation.


Assuntos
Neoplasias da Mama/patologia , Fator de Crescimento Epidérmico/farmacologia , Estradiol/farmacologia , Fator de Crescimento Transformador alfa/farmacologia , Sequência de Bases , Southern Blotting , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Divisão Celular/efeitos dos fármacos , Receptores ErbB/análise , Receptores ErbB/genética , Expressão Gênica , Humanos , Dados de Sequência Molecular , RNA Mensageiro/análise , RNA Mensageiro/genética , RNA Neoplásico/análise , RNA Neoplásico/genética , Células Tumorais Cultivadas
13.
Biochem Biophys Res Commun ; 170(2): 569-75, 1990 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-1696473

RESUMO

To elucidate the possible roles of proto-oncogenes and growth factors in estrogen-regulated cell proliferation of human breast and gynecologic cancers, we have determined the gene expressions of c-myc, transforming growth factor-alpha and beta 1 (TGF-alpha, beta 1) and epidermal growth factor receptor (EGFR) in a number of these cancer cell lines by using an intron-Differential (ID) RNA/PCR method, which differentially identifies the amplified cDNA from PCR products of genomic DNA contaminants. With this method, we demonstrated the expression of these genes, except EGFR, in an estrogen-dependent breast cancer cell line (CAMA-1). Our results show that TGF-alpha/EGF does not function as an autocrine factor in this cell line. Accordingly, it is unlikely that the TGF-alpha/EGFR system participates as a mediator in the estrogen-induced cell proliferation of CAMA-1 cells. The ID RNA/PCR method is a rapid, sensitive and specific technique for mRNA phenotyping and will have great clinical utility.


Assuntos
Receptores ErbB/genética , Amplificação de Genes , Neoplasias dos Genitais Femininos/genética , Oncogenes , Reação em Cadeia da Polimerase , RNA , Receptores de Superfície Celular/genética , Sequência de Bases , DNA , Receptores ErbB/biossíntese , Feminino , Expressão Gênica , Humanos , Íntrons , Dados de Sequência Molecular , Peso Molecular , Neoplasias Hormônio-Dependentes/genética , RNA/isolamento & purificação , Receptores de Superfície Celular/biossíntese , Receptores do Fator de Necrose Tumoral , Sensibilidade e Especificidade , Células Tumorais Cultivadas
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