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1.
J Atheroscler Thromb ; 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38311417

RESUMO

AIMS: Familial hypercholesterolemia (FH) is a genetic disorder characterized by elevated low-density lipoprotein cholesterol (LDL-C) levels, which increases the risk of premature coronary artery disease. Early detection and treatment are vital, especially in children. To improve FH diagnosis in children, the Japan Atherosclerosis Society (JAS) released new guidelines in July 2022. This study assessed and compared the sensitivity and specificity of the clinical diagnostic criteria from the JAS pediatric FH guidelines of 2017 and 2022. METHODS: From September 2020 to March 2023, 69 children with elevated plasma LDL-C levels (≥ 140 mg/dL) were included in a pediatric FH screening project in Kagawa. The children were evaluated using genetic testing alongside the clinical diagnostic criteria from the JAS pediatric FH guidelines of 2017 and 2022. RESULTS: Using the JAS pediatric FH 2017 criteria, eight children were diagnosed as FH-positive and 61 children as FH-negative. The JAS pediatric FH 2022 criteria identified 15 children with definite FH, 31 with probable FH, and 23 with possible FH. Genetic testing detected FH pathogenic variants in 24 children. The sensitivity and specificity for the JAS pediatric FH 2017 criteria were 0.292 and 0.978, respectively. For the JAS pediatric FH 2022 criteria, the sensitivity was 0.542 for definite FH with a specificity of 0.956, and 0.917 for probable FH with a specificity of 0.467. CONCLUSION: The clinical diagnostic criteria of the JAS pediatric FH 2022 guidelines demonstrated improved diagnostic efficiency compared with those of 2017, as evidenced by the increased sensitivity while preserving specificity.

2.
J Atheroscler Thromb ; 29(6): 839-849, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34176852

RESUMO

AIM: Familial hypercholesterolemia (FH) is an underdiagnosed autosomal dominant genetic disorder characterized by high levels of plasma low-density lipoprotein cholesterol (LDL-C) from birth. This study aimed to assess the genetic identification of FH in children with high LDL-C levels who are identified in a universal pediatric FH screening in Kagawa, Japan. METHOD: In 2018 and 2019, 15,665 children aged 9 or 10 years underwent the universal lipid screening as part of the annual health checkups for the prevention of lifestyle-related diseases in the Kagawa prefecture. After excluding secondary hyper-LDL cholesterolemia at the local medical institutions, 67 children with LDL-C levels of ≥ 140 mg/dL underwent genetic testing to detect FH causative mutations at four designated hospitals. RESULTS: The LDL-C levels of 140 and 180 mg/dL in 15,665 children corresponded to the 96.3 and 99.7 percentile values, respectively. Among 67 children who underwent genetic testing, 41 had FH causative mutations (36 in the LDL-receptor, 4 in proprotein convertase subtilisin/kexin type 9, and 1 in apolipoprotein B). The area under the curve of receiver operating characteristic curve predicting the presence of FH causative mutation by LDL-C level was 0.705, and FH causative mutations were found in all children with LDL-C levels of ≥ 250 mg/dL. CONCLUSION: FH causative mutations were confirmed in almost 60% of the referred children, who were identified through the combination of the lipid universal screening as a part of the health checkup system and the exclusion of secondary hyper-LDL cholesterolemia at the local medical institutions.


Assuntos
Hiperlipoproteinemia Tipo II , Apolipoproteínas B/genética , Criança , LDL-Colesterol , Humanos , Hiperlipoproteinemia Tipo II/diagnóstico , Hiperlipoproteinemia Tipo II/epidemiologia , Hiperlipoproteinemia Tipo II/genética , Japão/epidemiologia , Mutação , Pró-Proteína Convertase 9/genética
3.
Neuroimage ; 224: 117434, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33039616

RESUMO

To minimize motion-related distortion of reconstructed images, conventional positron emission tomography (PET) measurements of the brain inevitably require a firm and tight head restraint. While such a restraint is now a routine procedure in brain imaging, the physiological and psychological consequences resulting from the restraint have not been elucidated. To address this problem, we developed a restraint-free brain PET system and conducted PET scans under both restrained and non-restrained conditions. We examined whether head restraint during PET scans could alter brain activities such as regional cerebral blood flow (rCBF) and dopamine release along with psychological stress related to head restraint. Under both conditions, 20 healthy male participants underwent [15O]H2O and [11C]Raclopride PET scans during working memory tasks with the same PET system. Before, during, and after each PET scan, we measured physiological and psychological stress responses, including the State-Trait Anxiety Inventory (STAI) scores. Analysis of the [15O]H2O-PET data revealed higher rCBF in regions such as the parahippocampus in the restrained condition. We found the binding potential (BPND) of [11C]Raclopride in the putamen was significantly reduced in the restrained condition, which reflects an increase in dopamine release. Moreover, the restraint-induced change in BPND was correlated with a shift in the state anxiety score of the STAI, indicating that less anxiety accompanied smaller dopamine release. These results suggest that the stress from head restraint could cause unsolicited responses in brain physiology and emotional states. The restraint-free imaging system may thus be a key enabling technology for the natural depiction of the mind.


Assuntos
Encéfalo/diagnóstico por imagem , Circulação Cerebrovascular/fisiologia , Dopamina/metabolismo , Cabeça , Memória de Curto Prazo , Tomografia por Emissão de Pósitrons/métodos , Restrição Física/psicologia , Estresse Psicológico/diagnóstico por imagem , Adulto , Ansiedade/diagnóstico por imagem , Ansiedade/metabolismo , Ansiedade/fisiopatologia , Encéfalo/metabolismo , Encéfalo/fisiopatologia , Radioisótopos de Carbono , Neuroimagem Funcional , Voluntários Saudáveis , Humanos , Masculino , Radioisótopos de Oxigênio , Putamen/diagnóstico por imagem , Putamen/metabolismo , Putamen/fisiopatologia , Racloprida , Estresse Fisiológico , Estresse Psicológico/metabolismo , Estresse Psicológico/fisiopatologia , Adulto Jovem
4.
Brain Stimul ; 14(1): 154-160, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33359603

RESUMO

BACKGROUND: Transcranial direct current stimulation (tDCS) to the dorsolateral prefrontal cortex (DLPFC) hypothetically modulates cognitive functions by facilitating or inhibiting neuronal activities chiefly in the cerebral cortex. The effect of tDCS in the deeper brain region, the basal ganglia-cortical circuit, remains unknown. OBJECTIVE: To investigate the interaction between γ-aminobutyric acid (GABA) concentrations and dopamine release following tDCS. METHOD: This study used a randomized, placebo-controlled, double-blind, crossover design. Seventeen healthy male subjects underwent active and sham tDCS (13 min twice at an interval of 20 min) with the anode placed at the left DLPFC and the cathode at the right DLPFC, followed by examinations with [11C]-raclopride positron emission topography (PET) and GABA-magnetic resonance spectroscopy (MRS). MRS voxels were set in the left DLPFC and bilateral striata. Paired t-tests and regression analyses were performed for PET and MRS parameters. RESULTS: MRS data analyses showed elevations in GABA in the left striatum along with moderate reductions in the right striatum and the left DLPFC after active tDCS. PET data analyses showed that reductions in [11C]-raclopride binding potentials (increase in dopamine release) in the right striatum were inversely correlated with those in the left striatum after active tDCS. GABA reductions in the left DLPFC positively correlated with elevations in GABA in the left striatum and with increases in right striatal dopamine release and negatively correlated with increases in left striatal dopamine release. CONCLUSION: The present results suggest that tDCS to the DLPFC modulates dopamine-GABA functions in the basal ganglia-cortical circuit.


Assuntos
Estimulação Transcraniana por Corrente Contínua , Encéfalo/diagnóstico por imagem , Dopamina , Método Duplo-Cego , Humanos , Espectroscopia de Ressonância Magnética , Masculino , Tomografia por Emissão de Pósitrons , Córtex Pré-Frontal/diagnóstico por imagem , Ácido gama-Aminobutírico
5.
PLoS One ; 15(4): e0231265, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32267872

RESUMO

Transcriptional co-activator with PDZ-binding motif (TAZ) plays versatile roles in the regulation of cell proliferation and differentiation. TAZ activity changes in response to the cellular environment such as mechanic and nutritional stimuli, osmolarity, and hypoxia. To understand the physiological roles of TAZ, chemical compounds that activate TAZ in cells are useful as experimental reagents. Kaempferol, TM-25659, and ethacridine are reported as TAZ activators. However, as each TAZ activator has a distinct property in cellular functions, additional TAZ activators are awaiting. We screened for TAZ activators and previously reported IB008738 as a TAZ activator that promotes myogenesis in C2C12 cells. In this study, we have characterized IBS004735 that was obtained in the same screening. IBS004735 also promotes myogenesis in C2C12 cells, but is not similar to IBS008738 in the structure. IBS004735 activates TAZ via Akt and has no effect on TAZ phosphorylation, which is the well-described key modification to regulate TAZ activity. Thus, we introduce IBS004735 as a novel TAZ activator that regulates TAZ in a yet unidentified mechanism.


Assuntos
Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Imidazóis/farmacologia , Desenvolvimento Muscular/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Tetrazóis/farmacologia , Transativadores/metabolismo , Proteínas Adaptadoras de Transdução de Sinal , Animais , Diferenciação Celular/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Células HEK293 , Humanos , Camundongos , Mioblastos Esqueléticos/metabolismo , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/genética , Transativadores/genética , Transfecção
6.
Radiol Phys Technol ; 12(2): 210-215, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30937726

RESUMO

The psoas-major muscle has been reported as a predictive factor of sarcopenia. The cross-sectional area (CSA) of the psoas-major muscle in axial images has been indicated to correlate well with the whole-body skeletal muscle mass. In this study, we evaluated the segmentation accuracy of low-dose X-ray computed tomography (CT) images of the psoas-major muscle using the U-Net convolutional neural network, which is a deep-learning technique. Deep learning has been recently known to outperform conventional image-segmentation techniques. We used fivefold cross validation to validate the segmentation performance (n = 100) of the psoas-major muscle. For the intersection over union and CSA ratio, segmentation accuracies of 86.0 and 103.1%, respectively, were achieved. These results suggest that the U-Net network is competitive compared with the previous methods. Therefore, the proposed technique is useful for segmenting the psoas-major muscle even in low-dose CT images.


Assuntos
Aprendizado Profundo , Processamento de Imagem Assistida por Computador/métodos , Músculos/diagnóstico por imagem , Doses de Radiação , Tomografia Computadorizada por Raios X , Automação , Feminino , Humanos , Vértebras Lombares , Masculino , Pessoa de Meia-Idade
7.
Transl Psychiatry ; 9(1): 115, 2019 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-30877269

RESUMO

Transcranial direct-current stimulation (tDCS) to the dorsolateral prefrontal cortex (DLPFC) has been established as an effective and noninvasive method to modulate cognitive function. Nevertheless, the mechanisms causing those cognitive changes under the tDCS remain largely unknown. We strove to elucidate the cognito-biological relation under the tDCS condition by examining whether the dopamine system activated by tDCS is involved in cognitive changes in human participants, or not. To evaluate the dopamine system, we used [11C]-raclopride positron emission tomography (PET) scanning: 20 healthy men underwent two [11C]-raclopride PET scans and subsequent neuropsychological tests. One scan was conducted after tDCS to the DLPFC. One was conducted after sham stimulation (control). Results of [11C]-raclopride PET measurements demonstrate that tDCS to the DLPFC caused dopamine release in the right ventral striatum. Neuropsychological tests for attentiveness revealed that tDCS to the DLPFC-enhanced participants' accuracy. Moreover, this effect was correlated significantly with dopamine release. This finding provides clinico-biological evidence, demonstrating that enhancement of dopamine signaling by tDCS in the ventral striatum is associated with attention enhancement.


Assuntos
Atenção , Dopamina/fisiologia , Córtex Pré-Frontal/fisiologia , Estimulação Transcraniana por Corrente Contínua , Estriado Ventral/fisiologia , Adulto , Estudos Cross-Over , Antagonistas de Dopamina/farmacocinética , Método Duplo-Cego , Voluntários Saudáveis , Humanos , Masculino , Testes Neuropsicológicos , Tomografia por Emissão de Pósitrons , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/efeitos dos fármacos , Racloprida/farmacocinética , Estriado Ventral/diagnóstico por imagem , Adulto Jovem
8.
Rapid Commun Mass Spectrom ; 32(23): 1991-1998, 2018 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-30153343

RESUMO

RATIONALE: Sulfur is widely distributed in nature, and sulfur isotopic measurements have been applied to elucidate the origin and transport of sulfuric compounds in the lithosphere, biosphere, and atmosphere. Analyses of samples containing small amounts of sulfur, such as the Antarctic ice core samples analyzed herein, require a high-sensitivity analytical method. METHODS: We developed a high-sensitivity sulfur isotopic ratio (δ34 S value) analytical system equipped with an elemental analyzer, a cryo-flow device, and an isotope ratio mass spectrometer, and established a measurement and calibration procedure. RESULTS: Using this system, we precisely measured the δ34 S values of samples containing 5-40 nmol sulfate. Test runs were performed on samples from the Antarctic shallow ice core DF01, and the data obtained were consistent with those obtained by previous studies that reported δ34 S values for Antarctic snow and ice samples of more than 200 g (containing more than 150 nmol sulfate). Among the analyzed samples, one showed a peak sulfate concentration in its depth profile that is considered to have resulted from a large volcanic eruption. The δ34 S value obtained at that depth in the sample was distinct from values at other depths and consistent with reported values for volcanic sulfates. CONCLUSIONS: The analytical system developed herein is a powerful tool for trace sulfur isotopic analyses. The results obtained from the DF01 ice core samples are the first step towards elucidating high-time-resolution (less than 1 year) paleo-environmental changes by sulfur isotopic analyses.

9.
Front Neurosci ; 12: 951, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30631263

RESUMO

Inhibition of action is involved in stopping a movement, as well as terminating unnecessary movement during performance of a behavior. The inhibition of single actions, known as response inhibition (Inhibition of the urge to respond before or after actions) has been widely investigated using the go/no-go task and stop signal task. However, few studies focused on phase and volition-related inhibition after an action has been initiated. Here, we used functional magnetic resonance imaging (fMRI) to investigate the neural correlates of planning and execution underlying the voluntary inhibition of ongoing action. We collected fMRI data while participants performed a continuous finger-tapping task involving voluntary and involuntary (externally directed) inhibition, and during the initiation of movement. The results revealed areas of significantly greater activation during the preparation of inhibition of an ongoing action during voluntary inhibition, compared with involuntary inhibition, in the supplementary (SMA) and pre-supplementary motor areas, dorsolateral prefrontal cortex, inferior frontal gyrus (IFG), inferior parietal lobe, bilateral globus pallidus/putamen, bilateral insula and premotor cortex. Focusing on the period of execution of inhibition of ongoing actions, an event-related fMRI analysis revealed significant activation in the SMA, middle cingulate cortex, bilateral insula, right IFG and inferior parietal cortex. Additional comparative analyses suggested that brain activation while participants were planning to inhibit an ongoing action was similar to that during planning to start an action, indicating that the same neural substrates of motor planning may be recruited even when an action is ongoing. The present finding that brain activation associated with inhibiting ongoing actions was compatible with that seen in response inhibition (urge to stop before/after actions) suggests that common inhibitory mechanisms for motor movement are involved in both actual and planned motor action, which makes our behavior keep going seamlessly.

10.
Front Neurosci ; 12: 1024, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30686988

RESUMO

[This corrects the article DOI: 10.3389/fnins.2018.00951.].

11.
J Nucl Med ; 57(2): 221-5, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26609179

RESUMO

UNLABELLED: With a large database, we aimed to evaluate sex-specific distinctive changes in brain glucose metabolism and morphology during normal aging using MRI and (18)F-FDG PET. METHODS: A total of 963 cognitively healthy adults were included in this study. All subjects completed a medical questionnaire, took the mini-mental state examination, and underwent brain MRI and whole-body (18)F-FDG PET. The MR and PET images were statistically analyzed using 3-dimensional stereotactic surface projection. All images were corrected for whole-brain pixel value to identify the brain regions with significant changes, and regions of interest were set up with reference to Brodmann areas. We evaluated morphologic and glucose metabolic changes by cross-sectional analysis. The baseline database consisted of subjects from 30 to 40 y old, and the age-step for comparison was 5-y ranges. We also compared sex-specific differences in MR and PET images in each age group. RESULTS: Regarding age-related changes, in both sexes brain atrophy was observed in the lateral frontal and parietal regions and glucose hypometabolism in the medial frontal regions. There were significant differences in these parameters between the sexes; parallel changes in volume and metabolism were manifested in the medial frontal cortex in men and in the lateral and medial temporal cortex in women. By contrast, metabolism-dominant reductions were manifested in the lateral and medial parietal cortex in men and in the ventrolateral prefrontal cortex, including the Broca area, in women. These differences became insignificant in individuals 66 y or older. CONCLUSION: Our brain mapping study with a large number of reference human brain data demonstrated age-related parallel changes between morphology and metabolism in the medial frontal regions and sex-specific hypometabolism in the parietal (male) and ventrolateral prefrontal (female) cortices. These findings may suggest an aging vulnerability in sex-specific brain regions: the parietal cortex for visuospatial ability in men and the Broca area for speech processing in women.


Assuntos
Envelhecimento/fisiologia , Química Encefálica , Encéfalo/anatomia & histologia , Encéfalo/crescimento & desenvolvimento , Adulto , Idoso , Idoso de 80 Anos ou mais , Anatomia Transversal , Feminino , Fluordesoxiglucose F18 , Lateralidade Funcional , Glucose/metabolismo , Humanos , Interpretação de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Lobo Parietal/anatomia & histologia , Lobo Parietal/diagnóstico por imagem , Lobo Parietal/crescimento & desenvolvimento , Córtex Pré-Frontal/anatomia & histologia , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/crescimento & desenvolvimento , Cintilografia , Compostos Radiofarmacêuticos , Valores de Referência , Caracteres Sexuais
12.
In Vivo ; 29(6): 701-10, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26546527

RESUMO

BACKGROUND/AIM: The flavonoid quercetin exerts significant anti-inflammatory activity against chronic infections, including periodontal disease. However, it is unclear whether combination of quercetin with other flavonoids enhances antioxidant and anti-inflammatory activity. To clarify the molecular mechanism responsible for the anti-inflammatory activity of quercetin, we investigated the antioxidant, cytotoxicity and anti-inflammatory activity of quercetin and its related compounds, catechin and epicatechin, and their combinations. MATERIALS AND METHODS: Radical-scavenging activities were determined by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay, and cytotoxicity against RAW264.7 cells was determined using a cell counting kit (CCK-8). The inhibitory effects of these compounds on the mRNA expression of cyclooxygenase-2 (Cox2), tumor necrosis factor-alpha (Tnfα) and nitric oxide synthase 2 (Nos2), in RAW264.7 cells stimulated with Porphyromonas gingivalis (Pg) fimbriae, was also determined using real-time polymerase chain reaction analysis. The phenolic O-H bond dissociation enthalpy (BDE) and quantum chemical parameters were calculated on the basis of density function theory (DFT) BLYP/6-31G*. RESULTS: The DPPH(•) radical-scavenging activity (EC50) of quercetin, catechin and epicatechin was 5.5, 7.7 and 6.2 µM, respectively, whereas the cytotoxicity (LC50) was 4.45, 4.80 and 4.95 mM, respectively. Quercetin had slightly higher cytotoxicity and anti-DPPH(•) activity than catechin and epicatechin. The BDE for the three flavonoids at the 4'-OH in the B ring, which is the initial active site, was about 75 kcal/mol. Furthermore, various combinations of quercetin with catechin or epicatechin exerted an antagonistic effect on anti-DPPH(•) activity. Gene expression of Cox2, Tnfα and Nos2 stimulated by exposure to Pg-fimbriae was markedly suppressed by quercetin, but was not modulated by its combination with epicatechin. The 50% inhibitory concentration of quercetin for Cox2 expression was approximately 10 µM, while that of catechin and epicatechin was approximately 500 µM. Values of the quantum chemical parameters softness (σ) and electronegativity (χ) were highest for quercetin among the three flavonoids tested. CONCLUSION: The potent anti-inflammatory activity of quercetin appears to be attributable to its high σ and χ values. Quercetin may be applicable as a preventive agent against inflammatory periodontal disease as a manifestation of systemic disease.


Assuntos
Sequestradores de Radicais Livres/administração & dosagem , Inflamação/tratamento farmacológico , Doenças Periodontais/tratamento farmacológico , Quercetina/administração & dosagem , Animais , Anti-Inflamatórios/administração & dosagem , Fímbrias Bacterianas/química , Fímbrias Bacterianas/microbiologia , Humanos , Inflamação/microbiologia , Inflamação/patologia , Macrófagos/efeitos dos fármacos , Macrófagos/microbiologia , Camundongos , Doenças Periodontais/microbiologia , Doenças Periodontais/patologia , Porphyromonas gingivalis/patogenicidade , Quercetina/análogos & derivados
13.
J Toxicol Sci ; 40(4): 495-500, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26165646

RESUMO

Dihydropyrazines (DHPs) are glycation intermediates generated both in vivo and in food. DHPs can lead to the formation of a variety of different radical species, which can lead to DNA damage and enzyme inhibition. In addition, the presence of DHPs can lead to a decrease in cellular glutathione (GSH) levels, and induce the expression of antioxidant genes. In this study, the products resulting from the reaction of DHP with GSH have been analyzed in detail, with some of the products being separated by reversed-phase HPLC. The structures of the isolated DHP-GSH adducts were determined by FAB-MS and NMR analyses. These data suggested that the reaction of DHP with a thiol moiety could be involved in oxidative stress, because an increase in the amount of DHP-GSH adducts would result in a decrease in the cellular GSH levels.


Assuntos
Antioxidantes/química , Antioxidantes/isolamento & purificação , Glutationa/química , Glutationa/isolamento & purificação , Pirazinas/química , Pirazinas/isolamento & purificação , Animais , Antioxidantes/metabolismo , Células/metabolismo , Cromatografia Líquida de Alta Pressão/métodos , Glutationa/metabolismo , Humanos , Espectroscopia de Ressonância Magnética , Estresse Oxidativo , Espectrometria de Massas de Bombardeamento Rápido de Átomos
14.
Exp Cell Res ; 336(2): 171-81, 2015 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-26116467

RESUMO

The development of the efficient screening system of detecting compounds that promote myogenesis and prevent muscle atrophy is important. Mouse C2C12 cells are widely used to evaluate myogenesis but the procedures of the assay are not simple and the quantification is not easy. We established C2C12 cells expressing the N-terminal green fluorescence protein (GFP) and the C-terminal GFP (GFP1-10 and GFP11 cells). GFP1-10 and GFP11 cells do not exhibit GFP signals until they are fused. The signal intensity correlates with the expression of myogenic markers and myofusion. Myogenesis-promoting reagents, such as insulin-like growth factor-1 (IGF1) and ß-guanidinopropionic acid (GPA), enhance the signals, whereas the poly-caspase inhibitor, z-VAD-FMK, suppresses it. GFP signals are observed when myotubes formed by GFP1-10 cells are fused with single nuclear GFP11 cells, and enhanced by IGF1, GPA, and IBS008738, a recently-reported myogenesis-promoting reagent. Fusion between myotubes formed by GFP1-10 and GFP11 cells is associated with the appearance of GFP signals. IGF1 and GPA augment these signals, whereas NSC23766, Rac inhibitor, decreases them. The conditioned medium of cancer cells suppresses GFP signals during myogenesis and reduces the width of GFP-positive myotubes after differentiation. Thus the novel split GFP-based assay will provide the useful method for the study of myogenesis, myofusion, and atrophy.


Assuntos
Proteínas de Fluorescência Verde/metabolismo , Desenvolvimento Muscular/efeitos dos fármacos , Fibras Musculares Esqueléticas/citologia , Atrofia Muscular/prevenção & controle , Mioblastos/citologia , Clorometilcetonas de Aminoácidos/farmacologia , Aminoquinolinas/farmacologia , Animais , Inibidores de Caspase/farmacologia , Diferenciação Celular , Fusão Celular , Linhagem Celular , Proteínas de Fluorescência Verde/genética , Guanidinas/farmacologia , Células HEK293 , Humanos , Imidazóis/farmacologia , Fator de Crescimento Insulin-Like I/farmacologia , Camundongos , Propionatos/farmacologia , Pirimidinas/farmacologia , Proteínas rac de Ligação ao GTP/antagonistas & inibidores
15.
In Vivo ; 29(3): 341-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25977379

RESUMO

BACKGROUND/AIM: Resveratrol is a polyphenol with efficient anti-oxidative and anti-inflammatory activity. To clarify the molecular mechanism responsible for its anti-inflammatory action, we investigated the radical scavenging activity, cytotoxicity and anti-inflammatory activity of resveratrol and its related compounds, orcinol and 4-allylphenol. MATERIALS AND METHODS: The radical scavenging activities of these compounds were determined by the DPPH (2,2'-diphenyl-1-picrylhydrazyl) assay and their cytotoxicities against RAW264.7 cells were determined using a cell-counting kit (CCK-8). The inhibitory effects of these compounds on cyclooxygenase-2 (Cox2) expression in RAW264.7 cells stimulated with Porphyromonas gingivalis (Pg) fimbriae were also determined using real-time polymerase chain reaction and western blot analysis, while inhibition of the fimbria-stimulated activation of nuclear factor-kappa B (Nf-κb) was evaluated using western blot analysis and enzyme-linked immunosorbent assay-like microwell colorimetric transcription factor activity assay, respectively. The quantum chemical parameters were calculated on the basis of the density function theory (DFT) BLYP/6-31G*. RESULTS: DPPH radical scavenging activity declined in the order resveratrol > orcinol > 4-allylphenol. The cytotoxicity of the compounds was in the order 4-allylphenol > resveratrol > orcinol. The inhibitory effect on Pg fimbria-stimulated Cox2 expression and Nf-κb activation was enhanced by resveratrol-alone. Resveratrol showed high electronegativity (χ) and softness (σ) values, as determined by quantum chemical calculations. CONCLUSION: Resveratrol exerts potent anti-inflammatory activity in RAW264.7 cells stimulated with Pg-fimbriae and may be applicable as a therapeutic agent for inflammatory periodontal disease as a manifestation of systemic disease.


Assuntos
Compostos Alílicos/farmacologia , Fímbrias Bacterianas/imunologia , Sequestradores de Radicais Livres/farmacologia , Fenóis/farmacologia , Porphyromonas gingivalis/imunologia , Resorcinóis/farmacologia , Estilbenos/farmacologia , Compostos Alílicos/química , Animais , Compostos de Bifenilo/química , Linhagem Celular , Avaliação Pré-Clínica de Medicamentos , Sequestradores de Radicais Livres/química , Radicais Livres/química , Camundongos , NF-kappa B/metabolismo , Fenóis/química , Picratos/química , Resorcinóis/química , Resveratrol , Estilbenos/química
16.
Int J Oncol ; 46(4): 1721-9, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25653196

RESUMO

The receptor tyrosine kinase epidermal growth factor receptor (EGFR) and its ligand epidermal growth factor (EGF) are known to play important roles in malignant tumor cells, and the EGFR signaling pathway is one of the most important targets in various tumors, including non-small cell lung cancer (NSCLC). We reported recently that an aberration in certain steps of EGF-stimulated phosphorylated epidermal growth factor receptor (pEGFR) endocytic trafficking from the early endosomes to the late endosomes occurs in the gefitinib-resistant NSCLC cells, in which large amounts of sorting nexin 1 (SNX1) are colocalized with EGFR in the aggregated early endosomes where the internalized pEGFR is also accumulated of these cells. To further investigate the role of SNX1 in EGF­stimulated pEGFR endocytosis, followed by downstream signaling leading to the activation of phosphatidylinositol 3-kinase (PI3K)--the serine/threonine kinase AKT pathway, we examined the effect of depletion of SNX1 knock-down expression by siRNA and an inhibition of targeting membrane recycling using monensin. Using immunofluorescence, we observed an efficient endocytic transport of pEGFR from early endosomes to late endosomes/lysosomes after EGF-stimulation in the cells transfected with siRNA­SNX1, whereas the delayed endocytic delivery of pEGFR was evident in the siRNA-control-transfected cells. Furthermore, a large amount of endocytosed pEGFR was accumulated in the presence of monensin in the early endosomes of the SNX1 knock-down cells. In western blot analysis, EGF stimulation of both control and cells transfected with siRNA-SNX1 resulted in rapid phosphorylation of EGFR and enhanced AKT phosphorylation. Monensin-dependent inhibition of AKT phosphorylation was stronger in SNX1 knock-down cells than in controls. In contrast, however, monensin had no effect on AKT phosphorylation triggered by activation of the MET receptor tyrosine kinase. Collectively, we suggest that EGF-stimulated recycling of EGFR to the plasma membrane induces downstream signaling leading to AKT phosphorylation. Suppression of EGFR membrane recycling by SNX1 appears to be critical for the activation of EGFR/PI3K/AKT signaling pathway in human lung cancer cells.


Assuntos
Fator de Crescimento Epidérmico/farmacologia , Receptores ErbB/metabolismo , Neoplasias Pulmonares/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Quinazolinas/farmacologia , Nexinas de Classificação/metabolismo , Linhagem Celular Tumoral , Membrana Celular/metabolismo , Resistencia a Medicamentos Antineoplásicos , Endocitose/efeitos dos fármacos , Gefitinibe , Técnicas de Silenciamento de Genes , Humanos , Neoplasias Pulmonares/patologia , Monensin/farmacologia , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Nexinas de Classificação/genética
17.
In Vivo ; 28(5): 719-25, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25189882

RESUMO

BACKGROUND/AIM: Phenolic compounds, particularly dihydroxybiphenyl-related compounds, possess efficient anti-oxidative and anti-inflammatory activity. We investigated the anti-inflammatory activity of 2,2'-dihydroxy-5,5'-dimethylbiphenol (p-cresol dimer), 2,2'-dihydroxy-5,5'-dimethoxybiphenol (pHA dimer), p-cresol, p-hydroxyanisole (pHA) and 2-t-butyl-4-hydroxyanisole (BHA). MATERIALS AND METHODS: The cytotoxicity of the investigated compounds against RAW264.7 cells was determined using a cell counting kit (CCK-8). Their inhibitory effects on cyclooxygenase-2 (Cox2) mRNA expression stimulated by lipopolysaccharide (LPS) were determined using northern blot analysis, and their inhibition of LPS-stimulated nuclear factor-kappa B (Nf-κb) activation was evaluated using enzyme-linked immunosorbent assay-like microwell colorimetric transcription factor activity assay. The molecular orbital energy was calculated on the basis of density function theory BLYP/6-31G*. RESULTS: The cytotoxicity of the compounds declined in the order pHA dimer > p-cresol dimer > BHA > p-cresol > pHA. The inhibitory effect on Cox2 expression and Nf-κb activation was enhanced by p-cresol dimer and pHA dimer, particularly the former, suggesting potent anti-inflammatory activity, whereas p-cresol and pHA showed weak activity, and BHA no activity. Both p-cresol dimer and pHA dimer were highly electronegative, as determined by quantum chemical calculations. CONCLUSION: Dimerization of p-cresol and pHA enhances their anti-inflammatory activity. p-Cresol dimer and pHA dimer, particularly the former, are potent anti-inflammatory agents.


Assuntos
Anisóis/farmacologia , Cresóis/farmacologia , Ciclo-Oxigenase 2/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , NF-kappa B/metabolismo , Animais , Anisóis/química , Anisóis/toxicidade , Linhagem Celular , Cresóis/química , Cresóis/toxicidade , Ciclo-Oxigenase 2/genética , Dimerização , Relação Dose-Resposta a Droga , Ativação Enzimática/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Macrófagos/imunologia , Camundongos , RNA Mensageiro/genética
18.
Nihon Hoshasen Gijutsu Gakkai Zasshi ; 70(6): 542-8, 2014 Jun.
Artigo em Japonês | MEDLINE | ID: mdl-24953319

RESUMO

While point spread function (PSF)-based positron emission tomography (PET) reconstruction effectively improves the spatial resolution and image quality of PET, it may damage its quantitative properties by producing edge artifacts, or Gibbs artifacts, which appear to cause overestimation of regional radioactivity concentration. In this report, we investigated how edge artifacts produce negative effects on the quantitative properties of PET. Experiments with a National Electrical Manufacturers Association (NEMA) phantom, containing radioactive spheres of a variety of sizes and background filled with cold air or water, or radioactive solutions, showed that profiles modified by edge artifacts were reproducible regardless of background µ values, and the effects of edge artifacts increased with increasing sphere-to-background radioactivity concentration ratio (S/B ratio). Profiles were also affected by edge artifacts in complex fashion in response to variable combinations of sphere sizes and S/B ratios; and central single-peak overestimation up to 50% was occasionally noted in relatively small spheres with high S/B ratios. Effects of edge artifacts were obscured in spheres with low S/B ratios. In patient images with a variety of focal lesions, areas of higher radioactivity accumulation were generally more enhanced by edge artifacts, but the effects were variable depending on the size of and accumulation in the lesion. PET images generated using PSF-based reconstruction are therefore not appropriate for the evaluation of SUV.


Assuntos
Imagens de Fantasmas , Tomografia por Emissão de Pósitrons/métodos , Humanos , Tomografia Computadorizada por Raios X/métodos
19.
Mol Cell Biol ; 34(9): 1607-21, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24550007

RESUMO

The transcriptional coactivator with a PDZ-binding motif (TAZ) cooperates with various transcriptional factors and plays various roles. Immortalized human mammalian epithelial MCF10A cells form spheres when TAZ is overexpressed and activated. We developed a cell-based assay using sphere formation by TAZ-expressing MCF10A cells as a readout to screen 18,458 chemical compounds for TAZ activators. Fifty compounds were obtained, and 47 were confirmed to activate the TAZ-dependent TEAD-responsive reporter activity in HEK293 cells. We used the derived subset of compounds as a TAZ activator candidate minilibrary and searched for compounds that promote myogenesis in mouse C2C12 myoblast cells. In this study, we focused on one compound, IBS008738. IBS008738 stabilizes TAZ, increases the unphosphorylated TAZ level, enhances the association of MyoD with the myogenin promoter, upregulates MyoD-dependent gene transcription, and competes with myostatin in C2C12 cells. TAZ knockdown verifies that the effect of IBS008738 depends on endogenous TAZ in C2C12 cells. IBS008738 facilitates muscle repair in cardiotoxin-induced muscle injury and prevents dexamethasone-induced muscle atrophy. Thus, this cell-based assay is useful to identify TAZ activators with a variety of cellular outputs. Our findings also support the idea that TAZ is a potential therapeutic target for muscle atrophy.


Assuntos
Imidazóis/farmacologia , Peptídeos e Proteínas de Sinalização Intracelular/agonistas , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Desenvolvimento Muscular/efeitos dos fármacos , Músculos/efeitos dos fármacos , Músculos/lesões , Atrofia Muscular/prevenção & controle , Animais , Linhagem Celular , Avaliação Pré-Clínica de Medicamentos/métodos , Feminino , Células HEK293 , Humanos , Imidazóis/uso terapêutico , Peptídeos e Proteínas de Sinalização Intracelular/genética , Camundongos , Camundongos Endogâmicos BALB C , Músculos/patologia , Atrofia Muscular/induzido quimicamente , Atrofia Muscular/patologia , Proteína MyoD/metabolismo , Mioblastos/efeitos dos fármacos , Miogenina/genética , Regiões Promotoras Genéticas/efeitos dos fármacos , Transativadores , Fatores de Transcrição , Proteínas com Motivo de Ligação a PDZ com Coativador Transcricional , Regulação para Cima/efeitos dos fármacos
20.
ACS Comb Sci ; 16(2): 66-70, 2014 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-24367887

RESUMO

A thermoelectric evaluation system, attachable to our developed materials exploration system "M-ist Combi" based on the electrostatic spray deposition method, was designed and established for high-throughput to explore new candidate thermoelectric materials. The developed Seebeck coefficient measurement probe consists of two chromel-alumel thermocouples, and one of thermocouples is able to control its own temperature to ensure a temperature difference between thermocouples. The measurement time for each sample was about 5 s. This provides a stabilized time for the thermoelectric power for each sample. And, it was found that the Seebeck coefficient measurement probe could be used as a high-throughput screening tool for exploring candidate thermoelectric materials.


Assuntos
Técnicas Eletroquímicas/métodos , Desenho de Equipamento/métodos , Teste de Materiais/métodos , Pós/análise , Técnicas Eletroquímicas/instrumentação , Desenho de Equipamento/instrumentação , Teste de Materiais/instrumentação , Eletricidade Estática , Difração de Raios X
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