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1.
Transfus Med ; 27(6): 428-436, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28850748

RESUMO

BACKGROUND: ABO and its paralogues, such as A3GALT2 and GGTA1, encoding α1,3-Gal(NAc) transferases, belong to the glycosyltransferase 6 (GT6) gene family. We have developed an alternative method for the identification of species based on sequence variations within the GT6 gene family, which is applicable to degraded DNA. METHODS/MATERIALS: DNA samples prepared from control mammalian species, together with an unknown sample, were polymerase chain reaction (PCR)-amplified using one universal primer pair targeting the sequences in the last coding exons of the GT6 gene family, yielding 141-bp products derived from those multiple loci. After cloning, sequence determination and Basic Local Alignment Search Tool analysis, phylogenetic trees were constructed. RESULTS: Comparison of the sequences obtained with those references showed good concordance with each of the starting species of mammals. This system was able to identify 'mouse' or 'rodent' as the origin of the unknown sample. CONCLUSION: For the identification of species, genotyping of ABO and its homologues would be applicable for the analysis of degraded DNA samples. Although the method employed in this study is likely valid for mammals, it would not be suitable for birds, fish and reptiles. It may be possible to improve the present method for use with other species by employing an alternative universal primer set.


Assuntos
Sistema ABO de Grupos Sanguíneos/genética , Galactosiltransferases/genética , Filogenia , Análise de Sequência de DNA , Animais , Gatos , Cães , Humanos , Macaca fascicularis , Camundongos , Pan troglodytes , Especificidade da Espécie
2.
Vox Sang ; 110(1): 90-2, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26178450

RESUMO

Recent investigation of transcriptional regulation of the ABO genes has identified a candidate erythroid cell-specific regulatory element, named the +5·8-kb site, in the first intron of ABO. Six haplotypes of the site have been reported previously. The present genetic population study demonstrated that each haplotype was mostly linked with specific ABO alleles with a few exceptions, possibly as a result of hybrid formation between common ABO alleles. Thus, investigation of these haplotypes could provide a clue to further elucidation of ABO alleles.


Assuntos
Sistema ABO de Grupos Sanguíneos/genética , Células Eritroides/metabolismo , Haplótipos , Recombinação Genética , Sequências Reguladoras de Ácido Nucleico , Alelos , Humanos , Íntrons , Fenótipo
3.
Vox Sang ; 110(3): 285-7, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26529276

RESUMO

Recently, the involvement of mutation and deletion of transcription regulatory elements in the Bm , Am , A3 and B3 phenotypes has been reported. In the present study, we carried out genetic analysis of individuals with A3 and B3 using peptide nucleic acid-clamping PCR to exclude amplification of O alleles. Two single-point mutations, -76G>C and -68G>T, were found in the ABO promoter on the A-allele in three A3 individuals and on the B allele in a B3 individual, respectively. Transient transfection of luciferase reporter plasmids carrying the same mutations into K562 cells revealed decreased luciferase activity in comparison with that carrying the wild-type promoter. These observations suggest that the mutations downregulate the promoter activity, leading to reduction in A- or B-antigen expression on red blood cells in individuals with the A3 and B3 phenotypes.


Assuntos
Sistema ABO de Grupos Sanguíneos/genética , Alelos , Sequência de Bases , DNA/química , DNA/isolamento & purificação , DNA/metabolismo , Eritrócitos/metabolismo , Deleção de Genes , Genótipo , Humanos , Dados de Sequência Molecular , Ácidos Nucleicos Peptídicos/metabolismo , Fenótipo , Reação em Cadeia da Polimerase , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas , Elementos Reguladores de Transcrição
4.
Vox Sang ; 108(3): 310-3, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25523382

RESUMO

We developed a sequence-specific primer PCR (SSP-PCR) for detection of a 5.8-kb deletion (B(m) 5.8) involving an erythroid cell-specific regulatory element in intron 1 of the ABO blood group gene. Using this SSP-PCR, we performed genetic analysis of 382 individuals with Bm or ABm. The 5.8-kb deletion was found in 380 individuals, and disruption of the GATA motif in the regulatory element was found in one individual. Furthermore, a novel 3.0-kb deletion involving the element (B(m) 3.0) was demonstrated in the remaining individual. Comparisons of single-nucleotide polymorphisms and microsatellites in intron 1 between B(m) 5.8 and B(m) 3.0 suggested that these deletions occurred independently.


Assuntos
Sistema ABO de Grupos Sanguíneos/genética , Células Eritroides/metabolismo , Deleção de Genes , Íntrons , Regiões Promotoras Genéticas , Humanos , Dados de Sequência Molecular , Fenótipo , Polimorfismo de Nucleotídeo Único
5.
Vox Sang ; 108(3): 302-9, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25523606

RESUMO

BACKGROUND AND OBJECTIVES: Previously, a weak phenotype Am or Bm was assumed to be caused by a reduction of A or B gene expression in bone marrow cells, but not in mucus-secreting cells. However, ABO expression has not been examined in erythroid progenitor cells of Am or Bm individuals. MATERIALS AND METHODS: We carried out in vitro erythroid differentiation of CD34(+) cells from peripheral blood of a Bm individual harbouring a 3.0-kb deletion including an erythroid cell-specific regulatory element, named the +5.8-kb site, in intron 1 of the human ABO blood group gene. RESULTS: During the in vitro differentiation of CD34(+) cells from this Bm individual into erythroid cells, B-antigens were not detectable on the cultured cells by flow cytometric analysis, and allele-specific RT-PCR consistently detected the transcripts from the O allele, but not from the B allele. Moreover, chromatin immunoprecipitation assay demonstrated that both RUNX1 and GATA-2 or GATA-1 were bound to the +5.8-kb site in cultured erythroid cells expressing ABO. CONCLUSION: It is likely that the +5.8-kb site enhances transcription from the ABO promoter in erythroid cells through binding of RUNX1 and GATA-2 or GATA-1.


Assuntos
Sistema ABO de Grupos Sanguíneos/genética , Antígenos CD34/metabolismo , Células Eritroides/imunologia , Células Precursoras Eritroides/imunologia , Sistema ABO de Grupos Sanguíneos/metabolismo , Alelos , Antígenos CD34/genética , Células Cultivadas , Células Eritroides/citologia , Células Precursoras Eritroides/citologia , Hematopoese , Humanos , Regiões Promotoras Genéticas
6.
Vox Sang ; 106(2): 167-75, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23992526

RESUMO

BACKGROUND AND OBJECTIVES: An erythroid cell-specific regulatory element, referred to as the +5·8-kb site, had been identified in the first intron of the human ABO blood group gene. Subsequent studies revealed that either a 5·8-kb deletion including the +5·8-kb site or disruption of a GATA factor binding motif at the site was present in all Bm and ABm individuals examined. We investigated the molecular mechanism of the Am phenotype, which is analogous to the Bm phenotype. MATERIALS AND METHODS: Genomic DNAs were prepared from peripheral blood of two Am individuals, and the nucleotide sequences were investigated using PCR and direct sequencing. Electrophoretic mobility shift assay (EMSA) and promoter assay with K562 cells were carried out. RESULTS: A novel 23-bp nucleotide deletion was found at the +5·8-kb site in both individuals. EMSAs demonstrated binding of the transcription factor RUNX1 to the nucleotides within the deletion. Promoter assays showed that the deletion reduced the transcriptional activity of the +5·8-kb site. CONCLUSION: Deletion of the 23-bp nucleotides including the RUNX1 binding site decreases transcription of the A allele, resulting in the reduction in A antigen expression in the Am phenotype.


Assuntos
Sistema ABO de Grupos Sanguíneos/genética , Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , Elementos Reguladores de Transcrição , Alelos , Sequência de Bases , Sítios de Ligação , Elementos Facilitadores Genéticos , Humanos , Íntrons , Células K562 , Dados de Sequência Molecular , Fenótipo , Regiões Promotoras Genéticas , Deleção de Sequência , Transcrição Gênica
7.
Vox Sang ; 107(2): 171-80, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24602004

RESUMO

BACKGROUND AND OBJECTIVES: An erythroid cell-specific regulatory element, referred to as the +5.8-kb site, has been identified in the first intron of the human ABO blood group gene. Subsequent studies have revealed involvement of deletion or mutation at the site in phenotypes Am , Bm and ABm . We investigated the molecular mechanisms involved in the A3 and B3 phenotypes. MATERIALS AND METHODS: Genomic DNAs were prepared from peripheral blood of seven A3 individuals and twelve B3 or AB3 individuals, and the nucleotide sequences were investigated using PCR and sequencing. Promoter assays were performed with K562 cells. RESULTS: Two single point-mutations at +5893 or +5909 in the site on the A-allele were found in A3 individuals, while promoter assays revealed decreased activity at the site as a result of each substitution. In two B3 individuals, a single point-mutation at -77 in the ABO promoter on the B-allele was found, and the substitution was demonstrated to reduce the promoter activity. CONCLUSION: Nucleotide substitutions in the transcriptional regulatory elements such as the +5.8-kb site and the ABO promoter appear to decrease transcription from the A- and B-alleles, resulting in reduction in A- and B-antigen expression in A3 and B3, respectively.


Assuntos
Sistema ABO de Grupos Sanguíneos/genética , Elementos Facilitadores Genéticos , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas , Sequência de Bases , Células Eritroides/citologia , Estudos de Associação Genética , Humanos , Fenótipo
8.
J Oral Rehabil ; 41(8): 581-7, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24702545

RESUMO

The influence of masticatory loading stimulus on mandibular development is not fully clear. In this paper, experimental alterations in the daily muscle use, caused by a changed diet consistency, were continuously monitored, while adaptations in bone and cartilage were examined. It is hypothesised that decreased muscular loading will result in a decrease in the growth factor expression and mandible growth. Fourteen 21-day-old Wistar strain male rats were randomly divided into two groups and fed on either a hard or soft diet for 14 weeks. An implanted radio-telemetric device recorded continuously muscle activity of the superficial masseter muscle. Chondroblast proliferation in the condylar cartilage was identified by insulin-like growth factor-1 receptor (IGF-1r) immunostaining. Furthermore, an X-ray was taken for cephalometric analysis. In the soft-diet group, the duty time of the superficial masseter muscle at higher activity levels was significantly lower than that in the hard-diet group. This decrease in muscular loading of the jaw system was accompanied by: a significant reduction in (i) articular cartilage thickness, (ii) expression of IGF-1r immunopositive cells and (iii) mandible ramus height. In conclusion, a decrease in masticatory demand during the growth period leads to insufficient mandibular development.


Assuntos
Alimentos , Mandíbula/crescimento & desenvolvimento , Côndilo Mandibular/metabolismo , Músculo Masseter/fisiologia , Mastigação/fisiologia , Adaptação Fisiológica , Animais , Biomarcadores/metabolismo , Eletromiografia , Imuno-Histoquímica , Masculino , Contração Muscular/fisiologia , Fibras Musculares Esqueléticas/fisiologia , Distribuição Aleatória , Ratos , Ratos Wistar , Receptor IGF Tipo 1/metabolismo
9.
J Oral Rehabil ; 40(3): 205-13, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23331038

RESUMO

Parkinson's disease (PD), a major neurological disease, is characterised by a marked loss of dopaminergic neurons in the substantia nigra. Patients with PD frequently show chewing and swallowing dysfunctions, but little is known about the characteristics of their stomatognathic functions. The purpose of this study was to evaluate the influence of PD on jaw muscle fibre and functions. PD model rats were made by means of the injection of 6-hydroxydopamine (6-OHDA) into the striatum of 8-week-old Sprague-Dawley male rats. Five weeks after the injection, a radio-telemetric device was implanted to record muscle activity continuously from the superficial masseter and anterior belly of digastric muscles. Muscle activity was recorded for 3 days and was evaluated by the total duration of muscle activity per day (duty time). After recording the muscle activities, jaw muscles were isolated for immunohistochemical and PCR analyses. In PD model rats, the following findings of the digastrics muscles verify that compared to the control group: (i) the higher duty time exceeding 5% of the peak activity level, (ii) the higher expression of the mRNA of myosin heavy chain type I, and (iii) the tendency for fast to slow fibre-type transition. With respect to the masseter muscle, there were no significant differences in all analyses. In conclusion, PD leads to the changes in the jaw behaviours, resulting in a PD-specific chewing and swallowing dysfunctions.


Assuntos
Músculo Masseter/metabolismo , Fibras Musculares Esqueléticas/metabolismo , Cadeias Pesadas de Miosina/metabolismo , Doença de Parkinson/metabolismo , Animais , Estudos de Casos e Controles , Modelos Animais de Doenças , Eletromiografia/métodos , Masculino , Reação em Cadeia da Polimerase , Ratos , Ratos Sprague-Dawley
10.
Physiol Res ; 72(3): 371-382, 2023 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-37449749

RESUMO

Non-alcoholic fatty liver disease (NAFLD) is a general term for fatty liver disease not caused by viruses or alcohol. Fibrotic hepatitis, cirrhosis, and hepatocellular carcinoma can develop. The recent increase in NAFLD incidence worldwide has stimulated drug development efforts. However, there is still no approved treatment. This may be due in part to the fact that non-alcoholic steatohepatitis (NASH) pathogenesis is very complex, and its mechanisms are not well understood. Studies with animals are very important for understanding the pathogenesis. Due to the close association between the establishment of human NASH pathology and metabolic syndrome, several animal models have been reported, especially in the context of overnutrition. In this study, we investigated the induction of NASH-like pathology by enhancing cholesterol absorption through treatment with hydroxypropyl-beta-cyclodextrin (CDX). Female Sprague-Dawley rats were fed a normal diet with normal water (control group); a high-fat (60 kcal%), cholesterol (1.25 %), and cholic acid (0.5 %) diet with normal water (HFCC group); or HFCC diet with 2 % CDX water (HFCC+CDX group) for 16 weeks. Compared to the control group, the HFCC and HFCC+CDX groups showed increased blood levels of total cholesterol, aspartate aminotransferase, and alanine aminotransferase. At autopsy, parameters related to hepatic lipid synthesis, oxidative stress, inflammation, and fibrosis were elevated, suggesting the development of NAFLD/NASH. Elevated levels of endoplasmic reticulum stress-related genes were evident in the HFCC+CDX group. In the novel rat model, excessive cholesterol intake and accelerated absorption contributed to NAFLD/NASH pathogenesis.


Assuntos
Hipercolesterolemia , Hiperlipidemias , Hepatopatia Gordurosa não Alcoólica , Humanos , Ratos , Feminino , Animais , Hepatopatia Gordurosa não Alcoólica/induzido quimicamente , 2-Hidroxipropil-beta-Ciclodextrina/metabolismo , 2-Hidroxipropil-beta-Ciclodextrina/uso terapêutico , Ratos Sprague-Dawley , Dieta Hiperlipídica/efeitos adversos , Fígado/metabolismo , Colesterol , Hipercolesterolemia/metabolismo , Modelos Animais de Doenças
11.
Physiol Res ; 71(1): 113-123, 2022 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-35043654

RESUMO

Type 2 diabetes (T2D) is believed to be a non-autoimmune metabolic disorder. However, there are increasing reports that some T2D patients have immune abnormalities. In addition, it is known that there are sex differences in the onset of diabetes and immune responses in humans. Spontaneously Diabetic Torii (SDT) rats, a non-obese T2D model, also have sex differences in the onset of diabetes, but the involvement of immune abnormalities in diabetes is unknown. In this study, we investigated immune abnormalities in SDT rats. Immune cell subset analysis was performed in male and female SDT rats and control Sprague-Dawley (SD) rats at 5, 11, and 17 weeks of age. Male and female SDT rats had swelling of the spleen and lymph nodes and a higher number of T cells and B cells in the blood, spleen, and lymph nodes than SD rats. Only male SDT rats developed diabetes at 17 weeks of age, and the number of classical and non-classical monocytes in the blood and spleen of male SDT rats was higher than that in male SD rats and female SDT rats that did not develop diabetes. Most of these findings were observed before the onset of diabetes (~11 weeks of age), suggesting that classical and non-classical monocytes may contribute to the development of diabetes in male SDT rats. In conclusion, SDT rats may be a useful T2D model involved in immune abnormalities, and further research will help elucidate the pathophysiology of T2D with immune abnormalities and develop new therapeutic agents.


Assuntos
Diabetes Mellitus Tipo 2 , Doenças do Sistema Imunitário , Animais , Modelos Animais de Doenças , Feminino , Humanos , Masculino , Ratos , Ratos Sprague-Dawley , Caracteres Sexuais
12.
Physiol Res ; 70(1): 45-54, 2021 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-33453716

RESUMO

Glomerular hyperfiltration is observed in an early stage of kidney diseases including diabetic nephropathy. A better understanding of pathophysiological changes in glomerular hyperfiltration is essential for development of new therapies to prevent kidney disease progression. In this study, we investigated glomerular changes including glomerular filtration rate (GFR) and glomerular size in the Spontaneously Diabetic Torii (SDT) fatty rat, an obese type 2 diabetic model, and we also evaluated pharmacological effects of the sodium glucose cotransporter 2 inhibitor dapagliflozin on the renal lesions. Dapagliflozin was administered to SDT fatty rats from 5 to 17 weeks of age. Blood and urinary biochemical parameters were periodically measured. GFR was determined by transdermal GFR monitor at 16 weeks of age and histopathological analysis was performed at 17 weeks of age. SDT fatty rat developed severe hyperglycemia and exhibited pathophysiological abnormalities in the kidney, such as an increased GFR, glomerular hypertrophy and tissue lesions. Dapagliflozin achieved good glycemic control during the experimental period, inhibited the increase in GFR, and improved histopathological abnormalities in tubules. These results suggest that the SDT fatty rat is a useful model for analyzing the pathogenesis of diabetic nephropathy during its early stage and dapagliflozin improves not only hyperglycemia but also glomerular hyperfiltration and tubule lesions in SDT fatty rat.


Assuntos
Compostos Benzidrílicos/farmacologia , Diabetes Mellitus Experimental/fisiopatologia , Diabetes Mellitus Tipo 2/fisiopatologia , Nefropatias Diabéticas/etiologia , Glucosídeos/farmacologia , Hiperglicemia/patologia , Obesidade/complicações , Animais , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/patologia , Nefropatias Diabéticas/tratamento farmacológico , Modelos Animais de Doenças , Taxa de Filtração Glomerular , Hiperglicemia/tratamento farmacológico , Masculino , Obesidade/genética , Ratos , Ratos Sprague-Dawley , Inibidores do Transportador 2 de Sódio-Glicose/farmacologia
13.
J Anat ; 213(6): 743-8, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19094190

RESUMO

The behavioral differences in muscle use are related to the fiber type composition of the muscles among other variables. The aim of this study was to examine the degree of heterogeneity in the fiber type composition in the rat temporalis muscle. The temporalis muscle was taken from 10-week-old Wistar strain male rats (n = 5). Fiber types were classified by immunohistochemical staining according to their myosin heavy chain content. The anterior temporalis revealed an obvious regional difference of the fiber type distribution, whereas the posterior temporalis was homogeneous. The deep anterior temporalis showed a predominant proportion of type IIA fibers and was the only muscle portion displaying slow type fibers (< 10%). The other two muscle portions, the superficial anterior and posterior temporalis, did not differ significantly from each other and contained mainly type IIB fibers. Moreover, the deep anterior temporalis was the only muscle portion showing slow type fibers (< 10%). In the deep portion, type IIX fibers revealed the largest cross-sectional area (1943.1 +/- 613.7 microm(2)), which was significantly (P < 0.01) larger than those of type IIA and I + IIA fibers. The cross-sectional area of type IIB fibers was the largest in the remaining two muscle portions and was significantly (P < 0.01) larger than that of type IIX fibers. In conclusion, temporalis muscle in rats showed an obvious heterogeneity of fiber type composition and fiber cross-sectional area, which suggests multiple functions of this muscle.


Assuntos
Fibras Musculares Esqueléticas/ultraestrutura , Músculo Temporal/anatomia & histologia , Animais , Biomarcadores/análise , Imuno-Histoquímica , Masculino , Fibras Musculares de Contração Rápida/química , Fibras Musculares de Contração Rápida/ultraestrutura , Fibras Musculares Esqueléticas/química , Fibras Musculares de Contração Lenta/química , Fibras Musculares de Contração Lenta/ultraestrutura , Cadeias Pesadas de Miosina/análise , Ratos , Ratos Wistar
14.
Cell Death Differ ; 13(3): 404-14, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16397581

RESUMO

Renewed attention has been given lately to gangliosides and to their function as intracellular messengers of the adaptive responses to stress. Gangliosides are vital components of cell membranes; therefore, deleterious consequences can result from changes in their chemical composition and concentration, that is, membrane dynamics and structure can be altered as can the behavior of other membrane proteins. The importance of gangliosides in human health is evident in neurodegenerative diseases associated with defects in their degradation. As key modulators of intracellular calcium flux, gangliosides are involved in cellular processes downstream of calcium signaling. In this review, we focus on the effect of ganglioside accumulation on the endoplasmic reticulum calcium homeostasis and on the integrity of the mitochondrial membranes. We discuss how these events elicit an apoptotic program that ultimately leads to cell death. Owing to interorganelle crosstalk, these events are not necessarily self-contained, and gangliosides may serve as the common factor.


Assuntos
Apoptose , Retículo Endoplasmático/fisiologia , Gangliosídeos/metabolismo , Esfingolipidoses/etiologia , Animais , Modelos Animais de Doenças , Humanos , Mitocôndrias/metabolismo , Transdução de Sinais
15.
J Dent Res ; 85(6): 571-5, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16723658

RESUMO

The mandibular condylar cartilage plays an important role as a stress absorber during function. However, relatively little information is available on its dynamic properties under compression. We hypothesized that these properties are region-specific and depend on loading frequency. To characterize the viscoelastic properties of the condylar cartilage, we performed dynamic indentation tests over a wide range of loading frequencies. Ten porcine mandibular condyles were used; the articular surface was divided into 4 regions, anteromedial, anterolateral, posteromedial, and posterolateral. The dynamic complex, storage, and loss moduli increased with frequency, and these values were the highest in the anteromedial region. Loss tangent decreased with frequency from 0.68 to 0.17, but a regional difference was not found. The present results suggest that the dynamic compressive modulus is region-specific and is dependent on the loading frequency, which might have important implications for the transmission of load in the temporomandibular joint.


Assuntos
Cartilagem Articular/fisiologia , Côndilo Mandibular/fisiologia , Animais , Cartilagem Articular/anatomia & histologia , Força Compressiva , Elasticidade , Côndilo Mandibular/anatomia & histologia , Estresse Mecânico , Suínos , Articulação Temporomandibular/fisiologia , Viscosidade , Suporte de Carga
16.
Rev Sci Instrum ; 87(11): 11E124, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27910579

RESUMO

The InfraRed imaging Video Bolometer (IRVB) is a useful diagnostic for the multi-dimensional measurement of plasma radiation profiles. For the application of IRVB measurement to the neutron environment in fusion plasma devices such as the Large Helical Device (LHD), in situ calibration of the thermal characteristics of the foil detector is required. Laser irradiation tests of sample foils show that the reproducibility and uniformity of the carbon coating for the foil were improved using a vacuum evaporation method. Also, the principle of the in situ calibration system was justified.

17.
Rev Sci Instrum ; 87(11): 11D402, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27910411

RESUMO

The InfraRed Video Bolometer (IRVB) is a powerful tool to measure radiated power in magnetically confined plasmas due to its ability to obtain 2D images of plasma emission using a technique that is compatible with the fusion nuclear environment. A prototype IRVB has been developed and installed on NSTX-U to view the lower divertor. The IRVB is a pinhole camera which images radiation from the plasma onto a 2.5 µm thick, 9 × 7 cm2 Pt foil and monitors the resulting spatio-temporal temperature evolution using an IR camera. The power flux incident on the foil is calculated by solving the 2D+time heat diffusion equation, using the foil's calibrated thermal properties. An optimized, high frame rate IRVB, is quantitatively compared to results from a resistive bolometer on the bench using a modulated 405 nm laser beam with variable power density and square wave modulation from 0.2 Hz to 250 Hz. The design of the NSTX-U system and benchtop characterization are presented where signal-to-noise ratios are assessed using three different IR cameras: FLIR A655sc, FLIR A6751sc, and SBF-161. The sensitivity of the IRVB equipped with the SBF-161 camera is found to be high enough to measure radiation features in the NSTX-U lower divertor as estimated using SOLPS modeling. The optimized IRVB has a frame rate up to 50 Hz, high enough to distinguish radiation during edge-localized-modes (ELMs) from that between ELMs.

18.
Rev Sci Instrum ; 87(11): 11D410, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27910451

RESUMO

The infrared imaging video bolometer (IRVB) measures plasma radiated power images using a thin metal foil. Two different designs with a tangential view of NSTX-U are made assuming a 640 × 480 (1280 × 1024) pixel, 30 (105) fps, 50 (20) mK, IR camera imaging the 9 cm × 9 cm × 2 µm Pt foil. The foil is divided into 40 × 40 (64 × 64) IRVB channels. This gives a spatial resolution of 3.4 (2.2) cm on the machine mid-plane. The noise equivalent power density of the IRVB is given as 113 (46) µW/cm2 for a time resolution of 33 (20) ms. Synthetic images derived from Scrape Off Layer Plasma Simulation data using the IRVB geometry show peak signal levels ranging from ∼0.8 to ∼80 (∼0.36 to ∼26) mW/cm2.

19.
Atherosclerosis ; 64(1): 7-12, 1987 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3593462

RESUMO

Increased concentration of plasma low-density lipoprotein (LDL) is one of the risk factors in atherosclerosis. We studied how DNA synthesis of human arterial smooth muscle cells (SMC) was influenced in the culture added with or without small dose (25 micrograms of protein/ml) of LDL. LDL were ultracentrifugally obtained from normal subjects and diabetics. DNA synthesis was investigated at 6-h intervals during 36 h in the culture with or without LDL using [methyl-3H]thymidine. We found that DNA synthesis reached a maximum value at 24 h after addition of LDL. On the other hand sequential changes were not detectable in the culture without LDL addition. This effect of diabetic LDL was significantly (P less than 0.001) greater than that of normal LDL. These results suggested that LDL induces synchronization of the cultured SMC to synthesize DNA and diabetic LDL may play an atherogenic role more strongly than normal LDL in the arterial wall even in the normal range of LDL concentration.


Assuntos
Artérias/metabolismo , DNA/biossíntese , Lipoproteínas LDL/biossíntese , Músculo Liso Vascular/metabolismo , Artérias/citologia , Células Cultivadas , Feminino , Humanos , Masculino , Músculo Liso Vascular/citologia , Timidina/metabolismo , Fatores de Tempo
20.
J Nucl Med ; 22(1): 72-7, 1981 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7452356

RESUMO

Performance measurements of scintillation cameras are made (a) by the manufacturer to test and specify the equipment he sells, (b) by the customer as part of his acceptance testing, and (c) by the user as part of a periodic quality-control program. This paper describes the NEMA (National Electrical Manufacturer's Association) standard, which was developed to provide a uniform criterion for the measurement and reporting of performance parameters for scintillation cameras, and by which a manufacturer may specify his device. The purpose of this paper is to familiarize the nuclear medicine practitioner with the standard, the measurement methods, the reasons for them, and the meaning of the reported values.


Assuntos
Cintilografia/instrumentação , Controle de Qualidade
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