RESUMEN
To measure the extended-range neutron spectra and calibrate the extended-range neutron dosemeters of the China initiative Accelerator-Driven System (CiADS), an Extended-range Bonner Sphere Spectrometer (EBSS) has been developed. The EBSS was designed based on the PHITS codes, investigating various combinations of materials and diameters of the neutron moderators and the neutron multipliers for extended-range neutrons. Finally, seven polyethylene-only spheres and seven extended-range spheres were selected and subsequently built. The neutron multipliers of the extended-range spheres embedded concentric shells of lead, copper and tungsten. The response functions of the EBSS were analyzed and experimentally validated. It was subsequently tested with 252Cf neutron source and cosmic ray neutron source. The results demonstrate that the EBSS is capable of accurately measuring neutron spectra.
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Neutrones , Polietileno , China , Dosis de Radiación , Diseño de EquipoRESUMEN
AIM: To systematically investigate the multisite reproducibility, test-retest reliability, and observer variability of non-respiratory-gated four-dimensional (4D) flow magnetic resonance imaging (MRI) in the thoracic great vessels for the assessment of blood flow and peak velocity. MATERIALS AND METHODS: Electrocardiogram (ECG)-gated 4D flow MRI data were acquired without respiratory gating in 10 healthy volunteers. To analyse multisite reproducibility, 4D flow was scanned at three different sites using a 3 T GE MRI machine with identical protocols for the group of participants. In addition, to evaluate test-retest reliability, the same volunteers were scanned in each centre during a second visit. Data analysis included calculation of peak systolic velocity and time-resolved and total flow of both the ascending aorta and pulmonary artery. Two observers conducted the above measurements to assess the interobserver variability. RESULTS: Multisite, test-retest, interobserver agreement were good for the calculation of total flow and peak systolic velocity (mean differences <10% of the average flow parameter). CONCLUSION: Non-respiratory-gated 4D MRI-based assessment of aortic and pulmonary blood flow can be performed with good reproducibility. It may facilitate the potential clinical application of this technique.
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Imagenología Tridimensional/métodos , Imagen por Resonancia Magnética/métodos , Arteria Pulmonar/fisiología , Adulto , Aorta , Electrocardiografía , Femenino , Voluntarios Sanos , Humanos , Masculino , Variaciones Dependientes del Observador , Valores de Referencia , Reproducibilidad de los Resultados , Adulto JovenRESUMEN
miR-382-3p can regulate apoptosis through multiple pathways, but the mechanism remains unknown. In this experiment, we explored whether miR-382-3p can modulate the N-methyL-D-aspartate (NMDA)- induced HT22 cell apoptosis by regulating the RhoC/ROCK1 signaling pathway. An excitatory neurotoxicity model of HT22 cells was induced in vitro with 2 mmol/L NMDA. The cells were divided into normal control, NMDA-induced, NMDA + miR-382-3p mimic, and NMDA + miR-382-3p inhibitor groups. The 3-(4,5)-dimethylthiahiazo (-z-y1)-3,5-di-phenytetrazoliumromide (MTT) method, Real-time PCR, Western blot, and flow cytometry were performed to investigate the mechanisms. The results found that NMDA can increase the oxidative stress of HT22 cells in a dose-dependent manner, downregulate the expression of miR-382-3p, upregulate the expression of mRNA and protein abundance of ROCK1 and RhoC, increase the expression levels of proapoptotic proteins Bax, Caspase-3, and Caspase-9, increase the apoptosis of HT22 cells, and reduce the activity and survival rate of HT22 cells. Compared with the NMDA-induced group, the miR-382-3p mimic-transfected HT22 cells increased the expression of miR- 382-3p, reduced the expression of the mRNA and protein abundance of ROCK1 and RhoC, inhibited the expression of proapoptotic proteins Bax, Caspase-3, and Caspase-9, reduced the apoptosis of HT22 cells, and increased the activity and survival rate of HT22 cells. The results suggest that increasing the expression of miR-382-3p can inhibit the activity of the RhoC/ROCK1 signaling pathway, reduce the expression of proapoptotic proteins, reduce the oxidative stress and apoptosis of HT22 cells, and increase the activity and survival rate of HT22 cells.
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Apoptosis , Línea Celular Tumoral , Humanos , MicroARNs/genética , N-Metilaspartato/toxicidad , Transducción de Señal , Quinasas Asociadas a rho , Proteína rhoC de Unión a GTPRESUMEN
Monoclonal antibodies (mAbs) against black rockfish Sebastes schlegeli serum immunoglobulin M (IgM) were developed, which showed a specific reaction with the heavy chain of S. schlegeli IgM in Western blotting and with surface IgM positive (sIgM+ ) lymphocytes in indirect immunofluorescence. mAb 2A6 was employed to investigate the antibody and sIgM+ lymphocyte responses of S. schlegeli injected with inactivated Edwardsiella tarda, by ELISA and flow cytometry. Compared with controls, the level of specific antibodies and the percentage of sIgM+ lymphocytes both increased in the immunized fish and simultaneously reached their peaks at day 35 after immunization.
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Anticuerpos Monoclonales , Inmunoglobulina M/inmunología , Perciformes/inmunología , Animales , Especificidad de Anticuerpos , Biomarcadores , Western Blotting , Ensayo de Inmunoadsorción Enzimática/veterinariaRESUMEN
Lymphocystis disease virus (LCDV) enters and infects the gill cells of flounder (Paralichthys olivaceus) via a 27.8 kDa membrane protein receptor. In the present study, immunohistochemistry was performed to locate the tissue distribution of this molecule in healthy flounder and showed that it was widely distributed in the tissues tested. Indirect enzyme-linked immunosorbent assay (ELISA) showed that the expression of the receptor in healthy flounder was highest in the gills and stomach, then in the skin, intestine and liver, followed by the spleen, head kidney, heart, ovary and brain and finally the kidney. On LCDV infection, ELISA indicated that the expression of the receptor, as determined by ELISA, was significantly upregulated in all tissues of LCDV-infected flounder compared with controls, but this expression decreased over the 4 weeks post infection. In contrast, real-time quantitative polymerase chain reaction demonstrated that the copy number of the LCDV gene in the tissues increased with time post infection, and that viral loads were higher in the tissues with higher expressions of the receptor. These results point to a correlation between high expression of the 27.8 kDa receptor and efficient LCDV propagation. The wide tissue distribution of the receptor might be one reason why LCDV can infect various tissues leading to systemic infection.
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Infecciones por Virus ADN/veterinaria , Enfermedades de los Peces/metabolismo , Proteínas de la Membrana/biosíntesis , Animales , Infecciones por Virus ADN/metabolismo , Ensayo de Inmunoadsorción Enzimática , Lenguado , Iridoviridae , Reacción en Cadena en Tiempo Real de la PolimerasaRESUMEN
The aim of present study is to explore the cytoprotection of curcumin against 1-methyl-4-phenylpridinium ions (MPP(+))-induced apoptosis and the molecular mechanisms underlying in PC12 cells. Our findings indicated that MPP(+) significantly reduced the cell viability and induced apoptosis of PC12 cells. Curcumin protected PC12 cells against MPP(+)-induced cytotoxicity and apoptosis not only by inducing overexpression of Bcl-2, but also reducing the loss of mitochondrial membrane potential (MMP), an increase in intracellular reactive oxygen species (ROS) and overexpression of inducible nitric oxide synthase (iNOS). The selective iNOS inhibitor AG partly blocked MPP(+)-induced apoptosis of PC12 cells. The results of present study suggested that the cytoprotective effects of curcumin might be mediated, at least in part, by the Bcl-2-mitochondria-ROS-iNOS pathway. Because of its non-toxic property, curcumin could be further developed to treat the neurodegenerative diseases which are associated with oxidative stress, such as Parkinson's disease (PD).
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1-Metil-4-fenilpiridinio/farmacología , Apoptosis/efectos de los fármacos , Curcumina/farmacología , Inhibidores Enzimáticos/farmacología , Herbicidas/farmacología , Mitocondrias/efectos de los fármacos , Animales , Óxido Nítrico Sintasa de Tipo II/fisiología , Enfermedad de Parkinson/tratamiento farmacológico , Proteínas Proto-Oncogénicas c-bcl-2/fisiología , Ratas , Especies Reactivas de Oxígeno/metabolismoRESUMEN
The protective effects of adenovirus-mediated glia cell line-derived neurotrophic factor (GDNF) gene transaction was investigated on cultured motoneurons. First, the dose- and time-response relationship of glutamate neurotoxicity was determined on spinal motoneuron cultures. Then, the effect of the gdnf recombinant adenovirus (AdCMVgdnf) was tested in this cellular model. AdCMVgdnf at 20 MOI (multiplicity of infection) was found to significantly reduce the cell loss of motoneurons, as compared to AdCMVgdnf at 20 MOI, the recombinant adenovirus containing the marker gene lacZ. Furthermore, the adenovirus was proved to mediate erogenous gene expression using X-Gal staining and a semi-quantitative RT-PCR method. These results suggested a therapeutic potential of adenovirus vector-mediated gdnf gene therapy in human motoneuron diseases.
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Células Cultivadas/efectos de los fármacos , Vectores Genéticos/uso terapéutico , Ácido Glutámico/farmacología , Neuronas Motoras/efectos de los fármacos , Factores de Crecimiento Nervioso , Proteínas del Tejido Nervioso/genética , Fármacos Neuroprotectores/metabolismo , Neurotoxinas/antagonistas & inhibidores , Adenoviridae/genética , Animales , Supervivencia Celular/genética , Células Cultivadas/metabolismo , Células Cultivadas/patología , Relación Dosis-Respuesta a Droga , Feto , Regulación Viral de la Expresión Génica/fisiología , Genes Reporteros/fisiología , Factor Neurotrófico Derivado de la Línea Celular Glial , Ácido Glutámico/metabolismo , Enfermedad de la Neurona Motora/tratamiento farmacológico , Enfermedad de la Neurona Motora/metabolismo , Enfermedad de la Neurona Motora/fisiopatología , Neuronas Motoras/metabolismo , Neuronas Motoras/patología , ARN Mensajero/metabolismo , RatasRESUMEN
[structure: see text]. The first synthesis of 2'-C-beta-trifluoromethyl pyrimidine ribonucleosides is described. 1,2,3,5-Tetra-O-benzoyl-2-C-beta-trifluoromethyl-alpha-D-ribofuranose (3) is prepared from 1,3,5-tri-O-benzoyl-alpha-D-ribofuranose (1) in three steps and converted to 3,5-di-O-benzoyl-2-C-beta-trifluoromethyl-alpha-D-1-ribofuranosyl bromide (5). The 1-bromo derivative (5) is found to be a powerful reaction intermediate for the synthesis of ribonucleosides. The reaction of silylated pyrimidines with (5) in the presence of HgO/HgBr2 affords exclusively the beta-anomers (6-8). Deprotection of (6-8) with ammonia in methanol yields the 2'-C-beta-trifluoromethyl nucleosides (9-11).
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Pirimidinas/síntesis química , Ribonucleósidos/síntesis química , Glicosilación , Conformación Molecular , Estructura Molecular , Pirimidinas/química , Ribonucleósidos/químicaRESUMEN
To study the variation of nitric oxide synthase (NOS) neurons in rats with learning-remembering barrier by immunohistochemistry and histochemistry. The number of NOS neurons decreased apparently in hippocampus CA1-4 of rats with learning-remembering barrier, there were lots of new NOS neurons in dentate gyrus granular cell grays and pear-shaped zone's cortex. It is suggested that NOS neurons of hippocampus exert very important action in rat's learning remembering; new NOS neurons in pear-shaped zone cortex and dentate gyrus granular cell grays may be a compensative reaction of the learning-remembering barrier, and they might exert important function in following recovery of learning-remembering function.