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1.
Opt Express ; 31(15): 24045-24053, 2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37475241

RESUMO

Image-based deep learning (IBDL) is an advanced technique for predicting the surface irradiation conditions of laser surface processing technology. In pulsed-laser surface processing techniques, the number of superimposed laser shots is one of the fundamental and essential parameters that should be optimized for each material. Our primary research aims to build an adequate dataset using laser-irradiated surface images and to successfully predict the number of superimposed shots using the pre-trained deep convolutional neural network (CNN) models. First, the laser shot experiments were performed on copper targets using a nanosecond YAG laser with a wavelength of 532 nm. Then, the training data were obtained with the different superimposed shots of 1 to 1024 in powers of 2. After that, we used several pre-trained deep CNN models to predict the number of superimposed laser shots. Based on the dataset with 1936 images, VGG16 shows a high validation accuracy, higher sensitivity, and more than 99% precision than other deep CNN models. Utilizing the VGG16 model with high sensitivity could positively impact the industries' time, efficiency, and overall production.

2.
Phys Rev Lett ; 128(8): 085001, 2022 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-35275668

RESUMO

A new type of self-sustained divertor oscillation is discovered in the Large Helical Device stellarator, where the peripheral plasma is detached from material diverters by means of externally applied perturbation fields. The divertor oscillation is found to be a self-regulation of an isolated magnetic field structure (the magnetic island) width induced by a drastic change in a poloidal inhomogeneity of the plasma radiation across the detachment-attachment transitions. A predator-prey model between the magnetic island width and a self-generated local plasma current (the bootstrap current) is introduced to describe the divertor oscillation, which successfully reproduces the experimental observations.

3.
Rev Sci Instrum ; 92(6): 063521, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34243579

RESUMO

The sensitivity of an infrared imaging video bolometer (IRVB) was improved for the measurement of relatively low energy plasma radiation from the viewpoint of the metal foil absorber material. The photon energy of the radiation was considered up to 1 keV for the divertor plasma measurement. The thickness of the foil absorber was evaluated not only for conventional heavy elements, e.g., platinum, but also for light elements by the relation between the photon energy and attenuation length and by mechanical strength. A heat-transfer calculation using ANSYS suggested that light elements with practical foil thickness provide a higher temperature rise of the foil absorber compared with heavier elements with practical foil thickness. The maximum of the temperature rise was evaluated using He-Ne laser irradiation onto absorber samples. The material dependence of the temperature rise has a similar tendency between calculations and experiments. Experimentally, the sensitivity of the IRVB improved from 280 to 110 µW/cm2 using titanium with 1 µm thickness compared with conventional platinum with 2.5 µm thickness. Consequently, the signal-to-noise ratio of the IRVB could be improved from 2.8 to 9.1.

4.
Rev Sci Instrum ; 92(6): 063516, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34243592

RESUMO

A new multi-tracer technique in the Tracer-Encapsulated Solid Pellet (TESPEL) method has been developed in order to acquire simultaneously the information about the behaviors of various impurities, i.e., to study concurrently the behaviors of low- and mid/high-Z impurities in magnetically confined high-temperature plasmas. In this new technique, an inorganic compound (for example, lithium titanate, Li2TiO3) is proposed to be used as a tracer embedded in the core of the TESPEL, instead of pure elements. The results of the proof-of-principle experiment clearly demonstrate the applicability of the new multi-tracer technique in the TESPEL method for the simultaneous study of behaviors of low- and mid/high-Z impurities in high-temperature plasmas.

5.
Rev Sci Instrum ; 92(3): 033518, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33820070

RESUMO

Diagnosing the amount of radiated power is an important research goal for fusion devices. This research aims at better understanding and diagnosing the radiated power from the Large Helical Device (LHD). The current radiated power estimate in the LHD is based on one wide-angle resistive bolometer. Because the estimate stems from one bolometer location toroidally and has a wide-angle poloidal view, this estimate does not take into account toroidal and poloidal radiation asymmetries that are observed in the LHD in discharges with gas puffing. This research develops a method based on the EMC3-Eirene model to calculate the set of coefficients for a weighted-sum method of estimating the radiated power. This study calculates these coefficients by using a least-squares method to solve for a coefficient set, using a variety of simulated cases generated by the EMC3-Eirene model, combined with corresponding geometric radiated power density considerations. If this set of coefficients is multiplied by the detector signal of each bolometer and summed up, this gives a total radiated power estimate. This new estimate takes into account toroidal and poloidal asymmetries by using the bolometer channels viewing different toroidal and poloidal locations, thereby reducing the estimation error and providing information about toroidal asymmetries.

6.
Rev Sci Instrum ; 89(10): 10E114, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30399915

RESUMO

An infrared imaging video bolometer was improved for application to a neutron environment in fusion plasma devices, i.e., the Large Helical Device (LHD). In order to calibrate the thermal characteristics of the activated foil absorber inside the plasma vacuum vessel, the remote-controlled in situ calibration system was improved with high-surface-flatness mirrors. Furthermore, the carbon coating method was improved by introducing a vacuum evaporation technique instead of the conventional spray technique to realize the coating on both sides of the absorber with reproducibility and uniformity. The optimal thickness of the coating was also determined. Owing to these coating improvements, the reproducibility of the effective emissivity on both sides especially was improved. Finally, the variation with the neutron irradiation of the thermal characteristics of the foil absorber was investigated. It was found that the effect was not significant for the total neutron emission of 3.6 × 1018 on LHD.

7.
Rev Sci Instrum ; 89(10): 103507, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30399930

RESUMO

A prototype of an infrared imaging bolometer (IRVB) was successfully tested on the Alcator C-Mod tokamak at the end of its 2016 campaign. The IRVB method interprets the power radiated from the plasma by measuring the temperature rise of a thin, ∼2 µm, Pt absorber that is placed in the torus vacuum and exposed, using a pinhole camera, to the full-spectrum of plasma's photon emission. The IRVB installed on C-Mod viewed the poloidal cross section of the core plasma and observed Ohmic and ion cyclotron range of frequency (ICRF)-heated plasmas. Analysis of total radiated power and on-axis emissivity from IRVB is summarized, and quantitative comparisons made to data from both resistive bolometers and AXUV diodes. IRVB results are clearly within a factor of two, but additional effort is needed for it to be used to fully support power exhaust research. The IRVB is shown to be immune to electromagnetic interference from ICRF which strongly impacts C-Mod's resistive bolometers. Results of the bench-top calibration are summarized, including a novel temperature calibration method useful for IRVBs.

8.
Skin Res Technol ; 23(4): 581-587, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28516727

RESUMO

BACKGROUND/PURPOSE: The aim of this study was to evaluate the longitudinal monitoring of angiogenesis in a murine full-thickness cutaneous wound healing model using high-resolution three-dimensional (3D) ultrasound imaging. METHODS: Two C57BL/6 mice were used. Two-dimensional (2D) ultrasound images with the Color Doppler mode were acquired at regular spatial intervals on day 9, 11, and 14 after wounding. 3D ultrasound images were processed by reconstructing the 2D ultrasound image sequences. The wounds were harvested on day 14 and serial sections were immunohistologically stained with an anti-CD31 antibody. RESULTS: 3D ultrasound imaging with the Color Doppler mode showed the distribution of microvascular growth on days 9, 11, and 14 after wounding (44.6%, 51.5%, and 27.3% in wound 1, 55.8%, 38.1%, and 35.1% in wound 2, 60.6%, 62.6%, and 63.1% in wound 3, and 15.8%, 42.0%, and 31.9% in wound 4, respectively). A correlation was observed between % vascularity measured by paired 2D ultrasound imaging with the Color Doppler mode and sections immunohistologically stained for the anti-CD31 antibody (r=0.927, 0.871, 0.717, and 0.913 for wounds 1, 2, 3, and 4, respectively. P<.01). CONCLUSION: These results indicate that high-resolution 3D ultrasound imaging is useful for longitudinally evaluating the distribution of microvascular growth over the course of healing.


Assuntos
Neovascularização Fisiológica/fisiologia , Pele/irrigação sanguínea , Cicatrização/fisiologia , Animais , Anticorpos/metabolismo , Feminino , Imageamento Tridimensional , Imuno-Histoquímica , Camundongos Endogâmicos C57BL , Microvasos/fisiologia , Molécula-1 de Adesão Celular Endotelial a Plaquetas/imunologia , Pele/lesões , Ultrassonografia Doppler Dupla , Ferimentos e Lesões/fisiopatologia
9.
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.

10.
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.

11.
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.

12.
Br Poult Sci ; 57(3): 375-80, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26986698

RESUMO

Trehalose is composed of two molecules of D-glucose joined by an α,α-1,1 glucosidic linkage and has antioxidative and anti-inflammatory effects. The present study investigated the effect of feeding a trehalose-supplemented diet on the growth performance, as well as the oxidative status and the intestinal innate immunity of juvenile chicks. A total of 16 d-old male broiler chicks were used in this study: two groups of 8 birds were fed on a 0% (control) or 0.5% trehalose-supplemented diet for 18 d. The mean body weight of the trehalose group was significantly greater than that of the control group, but feed efficiency was not altered by feeding the trehalose-supplemented diet. No differences in the levels of lipid peroxidation in skeletal muscle, liver and plasma were observed between the control and trehalose-supplemented groups. The mRNA levels of interferon-γ, tumour necrosis factor-like ligand 1A, interleukin-10, NADPH oxidase 4 and inducible NO synthase were significantly reduced by the trehalose supplementation. Our results suggest that dietary supplementation with trehalose after hatching may have beneficial effects on the growth performance of juvenile chicks, probably by improving their intestinal innate immunity.


Assuntos
Galinhas/crescimento & desenvolvimento , Galinhas/imunologia , Dieta/veterinária , Suplementos Nutricionais , Imunidade Inata/fisiologia , Intestino Delgado/imunologia , Trealose/metabolismo , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Suplementos Nutricionais/análise , Masculino , Oxirredução , Trealose/administração & dosagem
13.
Neurogastroenterol Motil ; 28(6): 827-36, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26787195

RESUMO

BACKGROUND: For the contraction and relaxation of gastric smooth muscles to occur, the intracellular Ca(2+) concentration must be increased and decreased, respectively. The Na(+) /Ca(2+) exchanger (NCX) is a plasma membrane transporter that is involved in regulating intracellular Ca(2+) concentrations. METHODS: To determine the role of NCX in gastrointestinal tissues, we examined electric field stimulation (EFS)-induced relaxations in the circular muscles of the gastric fundus in NCX1 and NCX2 heterozygote knockout mice (HET). KEY RESULTS: The myenteric plexus layers and the longitudinal and circular muscle layers in the gastric fundus of wild-type mice (WT) were strongly immunoreactive to NCX1 and NCX2. EFS induced a transient relaxation that was apparent during the stimulus and a sustained relaxation that persisted after the end of the stimulus. The amplitudes of EFS-induced transient relaxation and sustained relaxation were greater in NCX1 HET and NCX2 HET than in WT. When an inhibitor of nitric oxide synthase was added following the EFS, neither NCX1 HET nor NCX2 HET exhibited transient relaxation, similar to WT. Furthermore, when a PACAP antagonist was added following the EFS, sustained relaxation in NCX1 HET and NCX2 HET was not observed, similar to WT. Next, we examined the effect of NCX heterozygous deficiency on relaxation in response to NO and PACAP in smooth muscles. The magnitude of NOR-1- and PACAP-induced relaxations in NCX1 HET and NCX2 HET was similar to that of WT. CONCLUSIONS & INFERENCES: In this study, we demonstrate that NCX1 and NCX2 expressed in neurons regulate the motility in the gastric fundus.


Assuntos
Fundo Gástrico/fisiologia , Trânsito Gastrointestinal/fisiologia , Heterozigoto , Relaxamento Muscular/fisiologia , Trocador de Sódio e Cálcio/biossíntese , Animais , Motilidade Gastrointestinal/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Técnicas de Cultura de Órgãos , Trocador de Sódio e Cálcio/genética
14.
Mucosal Immunol ; 8(3): 444-63, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25669149

RESUMO

Mast cells (MCs) are cells of hematopoietic origin that normally reside in mucosal tissues, often near epithelial cells, glands, smooth muscle cells, and nerves. Best known for their contributions to pathology during IgE-associated disorders such as food allergy, asthma, and anaphylaxis, MCs are also thought to mediate IgE-associated effector functions during certain parasite infections. However, various MC populations also can be activated to express functional programs--such as secreting preformed and/or newly synthesized biologically active products--in response to encounters with products derived from diverse pathogens, other host cells (including leukocytes and structural cells), damaged tissue, or the activation of the complement or coagulation systems, as well as by signals derived from the external environment (including animal toxins, plant products, and physical agents). In this review, we will discuss evidence suggesting that MCs can perform diverse effector and immunoregulatory roles that contribute to homeostasis or pathology in mucosal tissues.


Assuntos
Anafilaxia/imunologia , Asma/imunologia , Hipersensibilidade Alimentar/imunologia , Imunidade nas Mucosas , Enteropatias Parasitárias/imunologia , Mastócitos/imunologia , Anafilaxia/genética , Anafilaxia/patologia , Animais , Asma/genética , Asma/patologia , Citocinas/genética , Citocinas/imunologia , Hipersensibilidade Alimentar/genética , Hipersensibilidade Alimentar/patologia , Expressão Gênica , Humanos , Imunoglobulina E/genética , Imunoglobulina E/imunologia , Enteropatias Parasitárias/genética , Enteropatias Parasitárias/patologia , Mastócitos/patologia , Camundongos , Mucosa/imunologia , Mucosa/patologia , Especificidade da Espécie
15.
Int Endod J ; 48(3): 277-82, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24847951

RESUMO

AIM: To investigate the effect of catechins on vascular endothelial growth factor (VEGF) production and cyclooxygenase-2 (COX-2) expression in human dental pulp cells (HDPC) stimulated with bacteria-derived factors or pro-inflammatory cytokines. METHODOLOGY: Morphologically fibroblastic cells established from explant cultures of healthy human dental pulp tissues were used as HDPC. HDPC pre-treated with catechins, epigallocatechin-3-gallate (EGCG) or epicatechin gallate (ECG), were exposed to lipopolysaccharide (LPS), peptidoglycan (PG), interlukin-1ß (IL-1ß) or tumour necrosis factor-α (TNF-α). VEGF production was examined by enzyme-linked immunosorbent assay, and COX-2 expression was assessed by immunoblot. RESULTS: EGCG and ECG significantly reduced LPS- or PG-mediated VEGF production in the HDPC in a dose-dependent manner. EGCG also prevented IL-1ß-mediated VEGF production. Although TNF-α did not enhance VEGF production in the dental pulp cells, treatment of 20 µg mL(-1) of EGCG decreased the level of VEGF. In addition, the catechins attenuated COX-2 expression induced by LPS and IL-1ß. CONCLUSIONS: The up-regulated VEGF and COX-2 expressions in the HDPC stimulated with these bacteria-derived factors or IL-1ß were diminished by the treatment of EGCG and ECG. These findings suggest that the catechins may be beneficial as an anti-inflammatory tool of the treatment for pulpal inflammation.


Assuntos
Catequina/farmacologia , Inibidores de Ciclo-Oxigenase 2/farmacologia , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Western Blotting , Catequina/análogos & derivados , Células Cultivadas , Polpa Dentária/citologia , Ensaio de Imunoadsorção Enzimática , Fibroblastos/efeitos dos fármacos , Humanos , Interleucina-1beta/farmacologia , Lipopolissacarídeos/farmacologia , Peptidoglicano/farmacologia , Fator de Necrose Tumoral alfa/farmacologia
16.
Rev Sci Instrum ; 85(11): 11E435, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25430342

RESUMO

The InfraRed imaging Video Bolometer (IRVB) is a powerful diagnostic to measure multi-dimensional radiation profiles in plasma fusion devices. In the Large Helical Device (LHD), four IRVBs have been installed with different fields of view to reconstruct three-dimensional profiles using a tomography technique. For the application of the measurement to plasma experiments using deuterium gas in LHD in the near future, the long-term effect of the neutron irradiation on the heat characteristics of an IRVB foil should be taken into account by regular in situ calibration measurements. Therefore, in this study, an in situ calibration system was designed.

17.
J Chem Phys ; 140(18): 184704, 2014 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-24832296

RESUMO

From the analysis of high-resolution Si 2p photoelectron and near-edge x-ray absorption fine structure (NEXAFS) spectra, we show that core level excitations of epitaxial silicene on ZrB2(0001) thin films are characteristically different from those of sp(3)-hybridized silicon. In particular, it is revealed that the lower Si 2p binding energies and the low onset in the NEXAFS spectra as well as the occurrence of satellite features in the core level spectra are attributed to the screening by low-energy valence electrons and interband transitions between π bands, respectively. The analysis of observed Si 2p intensities related to chemically distinct Si atoms indicates the presence of at least one previously unidentified component. The presence of this component suggests that the observation of stress-related stripe domains in scanning tunnelling microscopy images is intrinsically linked to the relaxation of Si atoms away from energetically unfavourable positions.

18.
J Clin Endocrinol Metab ; 99(7): E1341-51, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24758183

RESUMO

CONTEXT: Somatic mutations in genes that influence cell entry of calcium have been identified in aldosterone-producing adenomas (APAs) of adrenal cortex in primary aldosteronism (PA). Many adrenal glands removed for suspicion of APA do not contain a single adenoma but nodular hyperplasia. OBJECTIVE: The objective of the study was to assess multinodularity and phenotypic and genotypic characteristics of adrenals removed because of the suspicion of APAs. DESIGN AND METHODS: We assessed the adrenals of 53 PA patients for histopathological characteristics and immunohistochemistry for aldosterone (P450C18) and cortisol (P450C11) synthesis and for KCNJ5, ATP1A1, ATP2B3, and CACNA1D mutations in microdissected nodi. RESULTS: Glands contained a solitary adenoma in 43% and nodular hyperplasia in 53% of cases. Most adrenal glands contained only one nodule positive for P450C18 expression, with all other nodules negative. KCNJ5 mutations were present in 22 of 53 adrenals (13 adenoma and nine multinodular adrenals). An ATP1A1 and a CACNA1D mutation were found in one multinodular gland each and an ATP2B3 mutation in five APA-containing glands. Mutations were always located in the P450C18-positive nodule. In one gland two nodules containing two different KCNJ5 mutations were present. Zona fasciculata-like cells were more typical for KCNJ5 mutation-containing nodules and zona glomerulosa-like cells for the other three genes. CONCLUSIONS: Somatic mutations in KCNJ5, ATP1A1, or CACNA1D genes are not limited to APAs but are also found in the more frequent multinodular adrenals. In multinodular glands, only one nodule harbors a mutation. This suggests that the occurrence of a mutation and nodule formation are independent processes. The implications for clinical management remain to be determined.


Assuntos
Neoplasias do Córtex Suprarrenal/genética , Glândulas Suprarrenais/patologia , Adenoma Adrenocortical/genética , Hiperaldosteronismo/genética , Mutação , Neoplasias do Córtex Suprarrenal/metabolismo , Neoplasias do Córtex Suprarrenal/patologia , Adenoma Adrenocortical/metabolismo , Adenoma Adrenocortical/patologia , Adulto , Idoso , Aldosterona/metabolismo , Análise Mutacional de DNA , Feminino , Humanos , Hiperaldosteronismo/complicações , Hiperaldosteronismo/patologia , Hiperplasia/complicações , Hiperplasia/genética , Masculino , Pessoa de Meia-Idade , Carga Tumoral , Adulto Jovem
19.
J Physiol ; 592(6): 1341-52, 2014 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-24396061

RESUMO

Studies have shown increased incorporation of omega-3 fatty acids into whole skeletal muscle following supplementation, although little has been done to investigate the potential impact on the fatty acid composition of mitochondrial membranes and the functional consequences on mitochondrial bioenergetics. Therefore, we supplemented young healthy male subjects (n = 18) with fish oils [2 g eicosapentaenoic acid (EPA) and 1 g docosahexanoic acid (DHA) per day] for 12 weeks and skeletal muscle biopsies were taken prior to (Pre) and following (Post) supplementation for the analysis of mitochondrial membrane phospholipid composition and various assessments of mitochondrial bioenergetics. Total EPA and DHA content in mitochondrial membranes increased (P < 0.05) ∼450 and ∼320%, respectively, and displaced some omega-6 species in several phospholipid populations. Mitochondrial respiration, determined in permeabilized muscle fibres, demonstrated no change in maximal substrate-supported respiration, or in the sensitivity (apparent Km) and maximal capacity for pyruvate-supported respiration. In contrast, mitochondrial responses during ADP titrations demonstrated an enhanced ADP sensitivity (decreased apparent Km) that was independent of the creatine kinase shuttle. As the content of ANT1, ANT2, and subunits of the electron transport chain were unaltered by supplementation, these data suggest that prolonged omega-3 intake improves ADP kinetics in human skeletal muscle mitochondria through alterations in membrane structure and/or post-translational modification of ATP synthase and ANT isoforms. Omega-3 supplementation also increased the capacity for mitochondrial reactive oxygen species emission without altering the content of oxidative products, suggesting the absence of oxidative damage. The current data strongly emphasize a role for omega-3s in reorganizing the composition of mitochondrial membranes while promoting improvements in ADP sensitivity.


Assuntos
Ácidos Graxos Ômega-3/administração & dosagem , Músculo Quadríceps/metabolismo , Translocador 1 do Nucleotídeo Adenina/metabolismo , Translocador 2 do Nucleotídeo Adenina/metabolismo , Difosfato de Adenosina/metabolismo , Respiração Celular/fisiologia , Suplementos Nutricionais , Ácidos Docosa-Hexaenoicos/administração & dosagem , Ácidos Docosa-Hexaenoicos/farmacocinética , Ácido Eicosapentaenoico/administração & dosagem , Ácido Eicosapentaenoico/farmacocinética , Metabolismo Energético , Ácidos Graxos Ômega-3/farmacocinética , Humanos , Peróxido de Hidrogênio/metabolismo , Cinética , Masculino , Mitocôndrias Musculares/metabolismo , Membranas Mitocondriais/metabolismo , Estresse Oxidativo , Fosfolipídeos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Adulto Jovem
20.
Clin Exp Dermatol ; 38(1): 25-9, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22924529

RESUMO

A 59-year-old patient with diabetes mellitus had been treated with human recombinant insulin for 4 years. He developed a solid mass on his left abdomen at the insulin injection site, which had an overlying pigmented verrucous plaque and keratinized papules, similar to acanthosis nigricans (AN). On histological examination, the mass was found to contain a deposit of amyloid in the dermis, with hyperkeratosis, papillomatosis and acanthosis in the epidermis. Using immunohistochemistry, the amyloid deposits were found to be positive for insulin. A few cases of localized insulin-derived amyloid deposits at injection sites have been reported previously, but none had significant epidermal changes. The coexistence of dermal insulin-derived amyloidosis and an overlying AN-like change, as found in our patient, has not been reported previously, to our knowledge. The presence of a tumour-like lesion at the injection site should be carefully examined, as injection of insulin into amyloid deposits can result in insulin resistance.


Assuntos
Acantose Nigricans/induzido quimicamente , Amiloidose/induzido quimicamente , Injeções Subcutâneas/efeitos adversos , Insulina/efeitos adversos , Acantose Nigricans/patologia , Amiloidose/patologia , Comorbidade , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade
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