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1.
Phys Rev Lett ; 133(2): 025101, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-39073957

RESUMO

Gyrokinetic tokamak plasmas can exhibit intrinsic toroidal rotation driven by the residual stress. While most studies have attributed the residual stress to the parallel-momentum flux from the turbulent E×B motion, the parallel-momentum flux from the drift-orbit motion (denoted Π_{∥}^{D}) and the E×B-momentum flux from the E×B motion (denoted Π_{E×B}) are often neglected. Here, we use the global total-f gyrokinetic code XGC to study the residual stress in the core and the edge of a DIII-D H-mode plasma. Numerical results show that both Π_{∥}^{D} and Π_{E×B} make up a significant portion of the residual stress. In particular, Π_{∥}^{D} in the core is higher than the collisional neoclassical level in the presence of turbulence, while in the edge it represents an outflux of countercurrent momentum even without turbulence. Using a recently developed "orbit-flux" formulation, we show that the higher-than-neoclassical-level Π_{∥}^{D} in the core is driven by turbulence, while the outflux of countercurrent momentum from the edge is mainly due to collisional ion orbit loss. These results suggest that Π_{∥}^{D} and Π_{E×B} can be important for the study of intrinsic toroidal rotation.

2.
Phys Rev Lett ; 132(23): 235102, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38905687

RESUMO

Multimachine empirical scaling predicts an extremely narrow heat exhaust layer in future high magnetic field tokamaks, producing high power densities that require mitigation. In the experiments presented, the width of this exhaust layer is nearly doubled using actuators to increase turbulent transport in the plasma edge. This is achieved in low collisionality, high confinement edge pedestals with their gradients limited by turbulent transport instead of large-scale, coherent instabilities. The exhaust heat flux profile width and divertor leg diffusive spreading both double as a high frequency band of turbulent fluctuations propagating in the electron diamagnetic direction doubles in amplitude. The results are quantitatively reproduced in electromagnetic XGC particle-in-cell simulations which show the heat flux carried by electrons emerges to broaden the heat flux profile, directly supported by Langmuir probe measurements.

3.
Curr Res Toxicol ; 3: 100068, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35341120

RESUMO

The medicinal effects of Hericium erinaceus have been long documented in scientific studies of Eastern traditional medicine. It is widely consumed, because of its nutritional qualities and perceived health benefits. Also, it is rich in ß-glucans, which has been shown to have immunomodulating and antitumor effects. The objective of the present study was to investigate adverse effects, if any, of ß-glucan extract preparation from H. erinaceus in subchronic toxicity and genotoxicity studies. The conduct of these studies was in compliance with Good Laboratory Practice (GLP) and test guidelines established by the Organization for Economic Cooperation and Development (OECD). In the subchronic toxicity study, Sprague Dawley rats (12/sex/group) were administered (gavage) H. erinaceus ß-glucan extract preparation at dose levels of 0, 500, 1000 and 2000 mg/kg body weight (bw)/day for 90 days. Treatment with H. erinaceus ß-glucan extract preparation did not result in any toxicologically significant treatment-related changes in clinical observations, ophthalmic examinations, body weights, body weight gains, feed consumption, and organ weights. Clinical pathology including hematology, serum chemistry, urinalysisand terminal necropsy (gross or histopathology findings) did not reveal any treatment-related adverse effects. The results of genotoxicity studies as evaluated by gene mutations in Salmonella typhimurium, in vitro chromosome aberrations and in vivo micronucleus test in mice did not reveal any genotoxicity of H. erinaceus ß-glucan extract preparation. Based on the subchronic study, the no observed-adverse-effect level (NOAEL) for H. erinaceus ß-glucan extract preparation was determined as 2000 mg/kg bw/day, the highest dose tested.

4.
J Nutr Health Aging ; 25(5): 618-623, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33949628

RESUMO

OBJECTIVES: Neighborhood walkability has been found to be positively related to physical activity and negatively associated with risks of noncommunicable diseases. However, limited studies have examined its association with sarcopenia in older adults. Thus, this study aimed to examine the association between neighborhood walk score and risks of sarcopenia in a sample of older Taiwanese adults. DESIGN AND SETTING: This study was a cross-sectional investigation using telephone-based survey. PARTICIPANTS: A nationwide telephone-based survey targeting older adults (≥ 65 years) was conducted in Taiwan. MEASUREMENTS: Data on neighborhood walkability (determined by walk score of residential neighborhood), sarcopenia scores (measured by SARC-F), and personal characteristics were obtained. The relationships between walk score and risks of sarcopenia were examined using generalized additive models. RESULTS: A total of 1,056 older adults participated in the survey. In model 1 (sex and age) and model 2 (full-adjusted model), a nonlinear association between neighborhood walk score and risks of sarcopenia was observed. Results showed that risks of sarcopenia appear to be lower in neighborhoods with a 40-walk score (Car-Dependent; most errands require a car) and an 80-walk score (Very Walkable) and highest in the neighborhood with a 60-walk score (Somewhat Walkable). CONCLUSIONS: The study revealed a nonlinear relationship between neighborhood walkability and risks of sarcopenia in older adults in Asian context. Results provided information to urban designers and public health practitioners that more walkable neighborhood may not necessarily protect older adults from risks of sarcopenia.


Assuntos
Sarcopenia , Idoso , Estudos Transversais , Humanos , Características de Residência , Sarcopenia/epidemiologia , Caminhada
5.
Eur Cell Mater ; 35: 350-364, 2018 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-29926464

RESUMO

Tissue engineering has the potential to overcome the limitations of tracheal reconstruction. To tissue-engineer a tracheal cartilage, auricular chondrocytes were encapsulated in a photocurable poly(ethylene glycol)/poly(ε-caprolactone) (PEG/PCL) hydrogel. Chondrogenic genes, including Sox9, Acan and Col2a1, were up-regulated in auricular chondrocytes after 2 weeks of in vitro cultivation in the PEG/PCL hydrogel. Co-cultivation of 70 % auricular chondrocytes and 30 % bone marrow mesenchymal stem cells (BMSCs) accelerated the chondrogenic genes' expression in the PEG/PCL hydrogel. Cartilaginous matrix markers, including proteoglycans and collagen type II, were detected in the chondrocytes-encapsulated PEG/PCL hydrogel after 4 weeks of in vitro cultivation. The higher expression level of cartilaginous matrix markers was observed in the PEG/PCL hydrogel with co-cultivation of 70 % chondrocytes and 30 % BMSCs. After 4 weeks of ectopic cultivation in rabbits, the cylindrical PEG/PCL structure was sustained with the use of a luminal silicon stent. However, without the stent, the construct collapsed under a compression force. No fibrosis or vessel ingrowth were found in the PEG/PCL hydrogel after 4 weeks of ectopic cultivation, whereas the auricular chondrocytes showed proteoglycans' accumulation and collagen type II production. Rabbit auricular chondrocytes could survive and retain chondrogenic ability in the PEG/PCL hydrogel under both in vitro and in vivo conditions. While the PEG/PCL hydrogel did not show sufficient mechanical properties for supporting the cylindrical shape of the construct, the high chondrogenesis level of chondrocytes in the PEG/PCL hydrogel displayed the potential of this material for tracheal tissue engineering.


Assuntos
Condrócitos/citologia , Cartilagem da Orelha/citologia , Hidrogéis/farmacologia , Poliésteres/farmacologia , Polietilenoglicóis/farmacologia , Engenharia Tecidual/métodos , Traqueia/fisiologia , Animais , Células Cultivadas , Condrogênese/efeitos dos fármacos , Condrogênese/genética , Colágeno/metabolismo , Matriz Extracelular/efeitos dos fármacos , Matriz Extracelular/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Modelos Animais , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Poliésteres/química , Polietilenoglicóis/química , Proteoglicanas/metabolismo , Coelhos , Vimentina/metabolismo
6.
Radiography (Lond) ; 24(1): 72-78, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29306379

RESUMO

INTRODUCTION: The regular functions of CT-MRI registration include delineation of targets and organs-at-risk (OARs) in radiosurgery planning. The question of whether deformable image registration (DIR) could be applied to stereotactic radiosurgery (SRS) in its place remains a subject of debate. METHODS: This study collected data regarding 16 patients who had undergone single-fraction SRS treatment. All lesions were located close to the brainstem. CT and MRI two image sets were registered by both rigid image registration (RIR) and DIR algorithms. The contours of the OARs were drawn individually on the rigid and deformable CT-MRI image sets by qualified radiation oncologists and dosimetrists. The evaluation metrics included volume overlapping (VO), Dice similarity coefficient (DSC), and dose. The modified demons deformable algorithm (VARIAN SmartAdapt) was used for evaluation in this study. RESULTS: The mean range of VO for OARs was 0.84 ± 0.08, and DSC was 0.82 ± 0.07. The maximum average volume difference was at normal brain (17.18 ± 14.48 cm3) and the second highest was at brainstem (2.26 cm3 ± 1.18). Pearson correlation testing showed that all DIRs' OAR volumes were linearly and significantly correlated with RIRs' volume (0.679-0.992, two tailed, P << 0.001). The 100% dose was prescribed at gross tumor volume (GTV). The average maximum percent dose difference was observed in brainstem (26.54% ± 27.027), and the average mean dose difference has found at same organ (1.6% ± 1.66). CONCLUSION: The change in image-registration method definitely produces dose variance, and is significantly more what depending on the target location. The volume size of OARs, however, was not statistical significantly correlated with dose variance.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/radioterapia , Imageamento por Ressonância Magnética , Radiocirurgia , Planejamento da Radioterapia Assistida por Computador/métodos , Tomografia Computadorizada por Raios X , Algoritmos , Feminino , Humanos , Masculino , Órgãos em Risco , Imagens de Fantasmas , Dosagem Radioterapêutica , Estudos Retrospectivos
7.
Lupus ; 27(1): 66-75, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28534427

RESUMO

Objective We aimed to investigate risk of hepatitis B virus reactivation in systemic lupus erythematosus patients with different hepatitis B virus infection statuses receiving immunosuppressive therapy. Methods We retrospectively analyzed systemic lupus erythematosus patients with positive hepatitis B surface antigen or anti-hepatitis B core IgG antibody who underwent immunosuppressive therapies from January 2001 to December 2012 at a medical center in Taiwan for evidence of hepatitis B virus reactivation. Results During this period, 906 out of 3125 patients who were diagnosed with systemic lupus erythematosus received screening tests for hepatitis B virus. Thirty-eight patients were identified as hepatitis B surface antigen-positive. Fifteen of 38 (39.5%) hepatitis B surface antigen-positive patients developed hepatitis B virus reactivation, and 53.3% of these patients experienced severe hepatitis flare. Three of 157 hepatitis B surface antigen-negative/anti-hepatitis B core IgG antibody-positive patients (1.9%) experienced hepatitis B surface antigen seroreversion after immunosuppressive therapy. Five patients received prophylactic or preemptive antiviral therapy and none of them developed hepatitis B virus flares. A daily dose of prednisolone greater than 5 mg was a risk factor for hepatitis B reactivation by multivariate logistic analysis. Conclusions The risk of hepatitis B virus reactivation is high in lupus patients receiving immunosuppressive therapy. Antiviral prophylaxis or preemption can effectively reduce the incidence of hepatitis B virus reactivation in lupus patients.


Assuntos
Hepatite B/induzido quimicamente , Imunossupressores/efeitos adversos , Lúpus Eritematoso Sistêmico/complicações , Adulto , Feminino , Hepatite B/imunologia , Humanos , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Exacerbação dos Sintomas
8.
Regul Toxicol Pharmacol ; 92: 429-438, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29287801

RESUMO

Antrodia cinnamomea is one of the most highly valued mushrooms utilized in traditional Taiwanese therapeutic practices. Its neutral monosaccharides (mannose, glucose and xylose) linked by a ß-D-glucan chain have been claimed to be responsible for its health benefits. The objective of the present study was to investigate adverse effects, if any, of ß-glucan (∼65% pure) from A. cinnamomea in subchronic toxicity and mutagenicity studies. In the subchronic toxicity study, Sprague Dawley rats (12/sex/group) were followed Organization for Economic Cooperation and Development (OECD) test guideline with Good Laboratory Practice (GLP) application, and were administered (gavage) Antrodia mushroom ß-glucan preparation at dose levels of 0, 500, 1000 and 2000 mg/kg body weight (bw)/day for 90 days. Treatment with ß-glucan preparation did not result in any toxicologically significant treatment-related changes in clinical observations, ophthalmic examinations, body weights, body weight gains, feed consumption, and organ weights. The clinical pathology as studied by hematology, serum chemistry, urinalysis or terminal necropsy (gross or histopathology findings) did not reveal any treatment-related adverse effects. The results of mutagenicity studies as evaluated by gene mutations in Salmonella typhimurium, in vitro chromosome aberrations and in vivo micronucleus test in mice did not reveal any genotoxicity of ß-glucan preparation. Based on the subchronic study, the no observed-adverse-effect level (NOAEL) for ß-glucan preparation from Antrodia mushroom was determined as 2000 mg/kg bw/day, the highest dose tested.


Assuntos
Agaricales/química , Antrodia/química , beta-Glucanas/toxicidade , Animais , Células CHO , Linhagem Celular , Aberrações Cromossômicas/efeitos dos fármacos , Cricetulus , Relação Dose-Resposta a Droga , Feminino , Masculino , Camundongos , Camundongos Endogâmicos ICR , Testes de Mutagenicidade/métodos , Nível de Efeito Adverso não Observado , Tamanho do Órgão/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Testes de Toxicidade Subcrônica
9.
Phys Plasmas ; 24(5): 054508, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-29104419

RESUMO

As an alternative option to kinetic electrons, the gyrokinetic total-f particle-in-cell (PIC) code XGC1 has been extended to the MHD/fluid type electromagnetic regime by combining gyrokinetic PIC ions with massless drift-fluid electrons analogous to Chen and Parker [Phys. Plasmas 8, 441 (2001)]. Two representative long wavelength modes, shear Alfvén waves and resistive tearing modes, are verified in cylindrical and toroidal magnetic field geometries.

10.
Phys Rev Lett ; 118(17): 175001, 2017 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-28498701

RESUMO

Transport barrier formation and its relation to sheared flows in fluids and plasmas are of fundamental interest in various natural and laboratory observations and of critical importance in achieving an economical energy production in a magnetic fusion device. Here we report the first observation of an edge transport barrier formation event in an electrostatic gyrokinetic simulation carried out in a realistic diverted tokamak edge geometry under strong forcing by a high rate of heat deposition. The results show that turbulent Reynolds-stress-driven sheared E×B flows act in concert with neoclassical orbit loss to quench turbulent transport and form a transport barrier just inside the last closed magnetic flux surface.

11.
Osteoarthritis Cartilage ; 25(6): 976-985, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28011101

RESUMO

OBJECTIVE: Chronic kidney disease (CKD) is characterized by metabolic disturbances in calcium and phosphorus homeostasis as kidney function declines. Alterations in blood perfusion in bone resulting from arteriosclerosis of bone vessels may relate to the progression of CKD. Herein, change in dynamic contrast enhanced (DCE) MRI parameters (A: amplitude, kel: elimination constant, and kep: permeability rate constant) and MRI T2∗ relaxation time of the knee cartilage were measured in a rodent nephrectomy model in order to (1) examine the relationship of peripheral blood perfusion to CKD and (2) demonstrate the feasibility of using DCE-MRI parameters and MRI T2∗ as imaging biomarkers to monitor disease progression. DESIGN: Two groups of male Sprague-Dawley rats received either (1) no intervention or (2) 5/6 nephrectomy. RESULTS: We found that the CKD group (compared with the control group) had lower A and kel values and similar kep value in the lateral and medial articular cartilages beginning at 12 weeks (P < 0.05); statistically significantly higher T2∗ values in the lateral and medial articular cartilages beginning at 18 weeks (P < 0.05); statistically significantly decreased inner luminal diameter of the popliteal artery, and altered structure of the lateral and medial articular cartilages (P < 0.05). CONCLUSION: Perfusion deficiency and CKD may be related. DCE parameters and MRI T2∗ could serve as imaging biomarkers of cartilage degeneration in CKD progression.


Assuntos
Cartilagem Articular/diagnóstico por imagem , Articulação do Joelho/diagnóstico por imagem , Fluxo Sanguíneo Regional , Insuficiência Renal Crônica/diagnóstico por imagem , Animais , Cartilagem Articular/irrigação sanguínea , Modelos Animais de Doenças , Articulação do Joelho/irrigação sanguínea , Imageamento por Ressonância Magnética , Masculino , Nefrectomia , Ratos , Ratos Sprague-Dawley
12.
mBio ; 7(3)2016 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-27353753

RESUMO

UNLABELLED: Staphylococcus aureus produces numerous virulence factors, each contributing different mechanisms to bacterial pathogenesis in a spectrum of diseases. Alpha toxin (AT), a cytolytic pore-forming toxin, plays a key role in skin and soft tissue infections and pneumonia, and a human anti-AT monoclonal antibody (MAb), MEDI4893*, has been shown to reduce disease severity in dermonecrosis and pneumonia infection models. However, interstrain diversity and the complex pathogenesis of S. aureus bloodstream infections suggests that MEDI4893* alone may not provide adequate protection against S. aureus sepsis. Clumping factor A (ClfA), a fibrinogen binding protein, is an important virulence factor facilitating S. aureus bloodstream infections. Herein, we report on the identification of a high-affinity anti-ClfA MAb, 11H10, that inhibits ClfA binding to fibrinogen, prevents bacterial agglutination in human plasma, and promotes opsonophagocytic bacterial killing (OPK). 11H10 prophylaxis reduced disease severity in a mouse bacteremia model and was dependent on Fc effector function and OPK. Additionally, prophylaxis with 11H10 in combination with MEDI4893* provided enhanced strain coverage in this model and increased survival compared to that obtained with the individual MAbs. The MAb combination also reduced disease severity in murine dermonecrosis and pneumonia models, with activity similar to that of MEDI4893* alone. These results indicate that an MAb combination targeting multiple virulence factors provides benefit over a single MAb neutralizing one virulence mechanism by providing improved efficacy, broader strain coverage, and protection against multiple infection pathologies. IMPORTANCE: Alternative strategies to broad-spectrum antibiotics are required to combat the antibiotic resistance epidemic. Previous attempts at active or passive immunization against Staphylococcus aureus targeting single antigens have failed in clinical trials despite positive preclinical data. To provide broad disease and isolate coverage, an effective immunization strategy likely must target multiple virulence mechanisms of the pathogen. Herein, we tested a multimechanistic MAb combination targeting alpha toxin (AT) and clumping factor A (ClfA) that neutralizes AT-mediated cytotoxicity, blocks fibrinogen binding by ClfA, prevents bacterial agglutination, targets the bacteria for opsonophagocytic killing, and provides broad isolate coverage in a lethal-bacteremia model. Although each MAb alone was effective in bacteremia against some individual isolates, the MAb combination provided improved protection against other isolates. These results illustrate the importance of targeting multiple virulence mechanisms and highlight the potential for an MAb combination targeting AT and ClfA to effectively prevent S. aureus disease.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/imunologia , Toxinas Bacterianas/imunologia , Coagulase/imunologia , Infecções Estafilocócicas/imunologia , Infecções Estafilocócicas/prevenção & controle , Staphylococcus aureus/imunologia , Fatores de Virulência/imunologia , Animais , Anticorpos Antibacterianos/sangue , Anticorpos Antibacterianos/uso terapêutico , Anticorpos Monoclonais/isolamento & purificação , Anticorpos Neutralizantes/uso terapêutico , Carga Bacteriana , Modelos Animais de Doenças , Células HL-60 , Humanos , Imunização Passiva/métodos , Camundongos , Fagocitose , Infecções Estafilocócicas/sangue , Infecções Estafilocócicas/microbiologia
13.
J Hum Hypertens ; 30(8): 479-82, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26911534

RESUMO

Although the association between serum uric acid (SUA) levels and prehypertension has been reported in previous studies, it is unknown whether their relationship is similar in subjects with diabetes, pre-diabetes and normal glucose tolerance (NGT). This study thus aimed to investigate the relationship between SUA and prehypertension in subjects with different glycemic status, including NGT, pre-diabetes and diabetes. A total of 12 010 participants were included after excluding subjects with blood pressure ⩾140/90 mm Hg, history of hypertension, leukaemia, lymphoma, hypothyroidism, medication for hypertension and hyperuricemia and missing data. Subjects were divided into four groups based on SUA quartiles (male Q1: ⩽345.0, Q2: 345.0-392.6, Q3: 392.6-440.2, Q4: ⩾440.2 µmol l(-1) and female Q1: ⩽249.8, Q2: 249.8-285.5, Q3: 285.5-333.1, Q4: ⩾333.1 µmol l(-1)). Diabetes, pre-diabetes and NGT were assessed according to the 2010 American Diabetes Association diagnostic criteria. Normotension and prehypertension were defined according to the JNC-7 (The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure) criteria. The SUA was significantly higher in prehypertensive subjects as compared with normotensive subjects. SUA, as a continuous variable, was positively associated with prehypertension in subjects with NGT but not pre-diabetes and diabetes. Besides, NGT subjects with the highest quartile of SUA exhibited a higher risk of prehypertension after adjustment for other confounding factors. In pre-diabetes and diabetes groups, none of SUA quartiles was significantly related to prehypertension. SUA was significantly associated with an increased risk of prehypertension in subjects with NGT but insignificantly in subjects with pre-diabetes and diabetes.


Assuntos
Glicemia/análise , Pressão Sanguínea , Diabetes Mellitus/sangue , Hiperuricemia/sangue , Pré-Hipertensão/fisiopatologia , Ácido Úrico/sangue , Adulto , Biomarcadores/sangue , Estudos Transversais , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/epidemiologia , Feminino , Humanos , Hiperuricemia/diagnóstico , Hiperuricemia/epidemiologia , Masculino , Pessoa de Meia-Idade , Estado Pré-Diabético/sangue , Estado Pré-Diabético/diagnóstico , Estado Pré-Diabético/epidemiologia , Pré-Hipertensão/diagnóstico , Pré-Hipertensão/epidemiologia , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Taiwan/epidemiologia , Regulação para Cima
14.
Genet Mol Res ; 14(4): 17028-33, 2015 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-26681050

RESUMO

Despite sharing a similar genetic abnormality, patients with core binding factor acute myeloid leukemia (CBF-AML), which is characterized by the presence of t(8;21) or inv(16)/t(16;16), show heterogeneous survival. Other molecular or cytogenetic factors are supposed to have an impact on the prognosis. We enrolled 24 CBF-AML patients to determine the impact of cytogenetic abnormality, and c-KIT, FLT3, NPM1, and CEBPA mutations on the prognosis. Only three patients had the c-KIT mutation (3/24, 12.5%) and one had the FLT3 mutation. However, over half of the patients (14/24) harbored additional cytogenetic changes, including ten with loss of sexual chromosomes (LOS) [all in the t(8;21) group], and six had additional abnormalities (two cases had both LOS and additional abnormalities). From this small-number study, no association was found between c-KIT mutation and survival and relapse rate. However, additional chromosome abnormalities had a significant association with relapse of the disease (P = 0.027). Stem cell transplant had a trend of benefitting patients after relapse (P = 0.065). This implies that chromosome abnormalities occur in CBF-AML and might take part in the heterogeneous nature of CBF-AML.


Assuntos
Aberrações Cromossômicas , Fatores de Ligação ao Core/genética , Leucemia Mieloide Aguda/genética , Adulto , Idoso , Feminino , Humanos , Leucemia Mieloide Aguda/mortalidade , Masculino , Pessoa de Meia-Idade , Mutação , Nucleofosmina , Prognóstico , Proteínas Proto-Oncogênicas c-kit/genética , Adulto Jovem
15.
Int J Obes (Lond) ; 39(8): 1241-8, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25907313

RESUMO

OBJECTIVES: Mechanisms of the development of abnormal metabolic phenotypes among obese population are not yet clear. In this study, we aimed to screen metabolomes of both healthy and subjects with abnormal obesity to identify potential metabolic pathways that may regulate the different metabolic characteristics of obesity. METHODS: We recruited subjects with body mass index (BMI) over 25 from the weight-loss clinic of a central hospital in Taiwan. Metabolic healthy obesity (MHO) is defined as without having any form of hyperglycemia, hypertension and dyslipidemia, while metabolic abnormal obesity (MAO) is defined as having one or more abnormal metabolic indexes. Serum-based metabolomic profiling using both liquid chromatography-mass spectrometry and gas chromatography-mass spectrometry of 34 MHO and MAO individuals with matching age, sex and BMI was performed. Conditional logistic regression and partial least squares discriminant analysis were applied to identify significant metabolites between the two groups. Pathway enrichment and topology analyses were conducted to evaluate the regulated pathways. RESULTS: A differential metabolite panel was identified to be significantly differed in MHO and MAO groups, including L-kynurenine, glycerophosphocholine (GPC), glycerol 1-phosphate, glycolic acid, tagatose, methyl palmitate and uric acid. Moreover, several metabolic pathways were relevant in distinguishing MHO from MAO groups, including fatty acid biosynthesis, phenylalanine metabolism, propanoate metabolism, and valine, leucine and isoleucine degradation. CONCLUSION: Different metabolomic profiles and metabolic pathways are important for distinguishing between MHO and MAO groups. We have identified and discussed the key metabolites and pathways that may prove important in the regulation of metabolic traits among the obese, which could provide useful clues to study the underlying mechanisms of the development of abnormal metabolic phenotypes.


Assuntos
Glicemia/metabolismo , Inflamação/metabolismo , Obesidade/metabolismo , Adulto , Distribuição da Gordura Corporal , Índice de Massa Corporal , Feminino , Humanos , Inflamação/fisiopatologia , Masculino , Redes e Vias Metabólicas , Metaboloma , Metabolômica/métodos , Obesidade/fisiopatologia , Fatores de Risco , Taiwan
16.
Nat Commun ; 6: 6620, 2015 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-25782977

RESUMO

Current methods of chemical vapour deposition (CVD) of graphene on copper are complicated by multiple processing steps and by high temperatures required in both preparing the copper and inducing subsequent film growth. Here we demonstrate a plasma-enhanced CVD chemistry that enables the entire process to take place in a single step, at reduced temperatures (<420 °C), and in a matter of minutes. Growth on copper foils is found to nucleate from arrays of well-aligned domains, and the ensuing films possess sub-nanometre smoothness, excellent crystalline quality, low strain, few defects and room-temperature electrical mobility up to (6.0±1.0) × 10(4) cm(2) V(-1) s(-1), better than that of large, single-crystalline graphene derived from thermal CVD growth. These results indicate that elevated temperatures and crystalline substrates are not necessary for synthesizing high-quality graphene.

17.
QJM ; 108(6): 457-63, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25362095

RESUMO

BACKGROUND: The occurrence of inflammatory bowel disease (IBD) is higher in Western countries and is increasing worldwide. The incidence of IBDs is about nearly 20-fold in Western countries than Asia and has risen in Taiwan over the past few decades. Epidemiological studies have demonstrated an increased risk of colorectal cancer (CRC) in patients with IBD. The prevalence of IBD as well as IBD-associated CRC is changing and the risk of CRC in patients with IBD appears to be greater in Western countries, but CRC risk in IBD patients is less well understood in low endemic areas, such as Asia. METHODS: This population-based cohort study collected data from the Taiwan Health Insurance Research Database (from January 1998 to December 2011). In total, 10 650 patients with confirmed diagnosis of IBD served as the IBD cohort and 42 600 non-IBD subjects were enrolled. Cox proportional hazards regression was used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) were used to assess the risk of CRC. RESULTS: The incidence of CRC was slightly lower in the IBD cohort compared with that in the non-IBD cohort (0.94 vs. 1.13 per 1000 person-years), with an adjusted HR of 0.99 (95% CI: 0.71-1.37). More than four hospitalizations were associated with a significantly higher risk of CRC in IBD patients in the Cox model (adjusted HR = 3.48, 95% CI: 1.59-7.63). CONCLUSIONS: The risk for CRC was not increased among IBD patients overall, but appeared to be increased with cumulative frequency of hospitalizations for IBD.


Assuntos
Colite Ulcerativa/epidemiologia , Neoplasias Colorretais/epidemiologia , Doença de Crohn/epidemiologia , Hospitalização/estatística & dados numéricos , Adulto , Idoso , Estudos de Casos e Controles , Colite Ulcerativa/terapia , Doença de Crohn/terapia , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Taiwan/epidemiologia , Adulto Jovem
18.
Int J Obes (Lond) ; 39(2): 270-8, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24854430

RESUMO

BACKGROUND: Obesity is a severe health problem worldwide, which leads to multiple comorbidities including type 2 diabetes mellitus and cardiovascular diseases. Inflammation has been found to be an important characteristic of adipose tissue in obese subjects. However, obesity is also associated with compromised immune responses to infections and the impact of obesity on immune function has not been fully understood. SUBJECTS/METHODS: To clarify the role of obesity in the immune responses, we investigated the Toll-like receptor (TLR)-induced cytokine secretion by leukocytes from obese and lean subjects. We also investigated the relationship between insulin-induced intracellular signaling and cytokine production using peripheral blood mononuclear cells (PBMCs) and a monocytic cell line THP-1. RESULTS: We found decreased TLR-induced interferon-γ, interleukin-6 (IL-6) and tumor necrosis factor-α secretions and elevated IL-10 secretion by leukocytes from obese subjects when compared with lean controls. PBMCs from obese subjects showed enhanced basal Akt and glycogen synthase kinase-3ß (GSK-3ß) phosphorylation, which did not further increase with insulin and lipopolysaccharide (LPS) stimulation. We also found that LPS-induced IκBα degradation was inhibited in PBMCs from obese subjects. By using THP-1 cells with GSK-3ß knockdown or cells treated with hyperinsulinemic and high-fatty acid conditions, we found that LPS-induced nuclear factor κB (NF-κB) activation was inhibited and cyclic adenosine monophosphate response element-binding protein (CREB) activation was enhanced. CONCLUSIONS: These findings indicate that GSK-3ß is important in the regulation of NF-κB and CREB activation in leukocytes under the metabolic condition of obesity. Our study revealed a key mechanism through which metabolic abnormalities compromise leukocyte functions in people with obesity.


Assuntos
Quinase 3 da Glicogênio Sintase/metabolismo , Hiperinsulinismo/metabolismo , Hiperlipidemias/metabolismo , Interleucina-10/metabolismo , NF-kappa B/antagonistas & inibidores , Obesidade/metabolismo , Glicogênio Sintase Quinase 3 beta , Humanos , Hiperinsulinismo/imunologia , Hiperlipidemias/imunologia , Proteínas I-kappa B/metabolismo , Inflamação/imunologia , Leucócitos Mononucleares/metabolismo , Inibidor de NF-kappaB alfa , Obesidade/imunologia , Fosforilação , Transdução de Sinais , Fator de Necrose Tumoral alfa/metabolismo
19.
Plant Sci ; 229: 262-279, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25443852

RESUMO

Lithium (Li) toxicity in plants is, at a minimum, a function of Li(+) concentration, exposure time, species and growth conditions. Most plant studies with Li(+) focus on short-term acute exposures. This study examines short- and long-term effects of Li(+) exposure in Arabidopsis with Li(+) uptake studies and measured shoot mRNA transcript abundance levels in treated and control plants. Stress, pathogen-response and arabinogalactan protein genes were typically more up-regulated in older (chronic, low level) Li(+)-treatment plants and in the much younger plants from acute high-level exposures. The gene regulation behavior of high-level Li(+) resembled prior studies due to its influence on: inositol synthesis, 1-aminocyclopropane-1-carboxylate synthases and membrane ion transport. In contrast, chronically-exposed plants had gene regulation responses that were indicative of pathogen, cold, and heavy-metal stress, cell wall degradation, ethylene production, signal transduction, and calcium-release modulation. Acute Li(+) exposure phenocopies magnesium-deficiency symptoms and is associated with elevated expression of stress response genes that could lead to consumption of metabolic and transcriptional energy reserves and the dedication of more resources to cell development. In contrast, chronic Li(+) exposure increases expression signal transduction genes. The identification of new Li(+)-sensitive genes and a gene-based "response plan" for acute and chronic Li(+) exposure are delineated.


Assuntos
Arabidopsis/crescimento & desenvolvimento , Arabidopsis/genética , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Lítio/farmacologia , Desenvolvimento Vegetal/genética , Arabidopsis/efeitos dos fármacos , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Ontologia Genética , Genes de Plantas , Hidroponia , Redes e Vias Metabólicas/efeitos dos fármacos , Redes e Vias Metabólicas/genética , Família Multigênica , Desenvolvimento Vegetal/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Solo , Fatores de Tempo , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/genética
20.
Transpl Infect Dis ; 16(6): 1003-6, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25367218

RESUMO

Transmission of hepatitis C virus (HCV) to recipients of hematopoietic stem cell transplant (HSCT) occurs frequently from HCV viremic donors and causes complications. Here, we report the outcomes of 3 cases from our 265 allogeneic HSCTs, whose donors had HCV infections. Successful prevention of HCV transmission was noted in 1 recipient by pretreatment of the donor with peginterferon/ribavirin to undetectable levels of HCV viremia before stem cell harvest. This case stressed the important role of effective antiviral therapy and HCV RNA seronegativity before cell harvest for prevention of HCV transmission in HSCT.


Assuntos
Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Hepatite C/transmissão , Viremia , Adulto , Antivirais/administração & dosagem , Antivirais/uso terapêutico , Quimioterapia Combinada , Feminino , Hepacivirus/isolamento & purificação , Hepatite C/tratamento farmacológico , Hepatite C/virologia , Humanos , Interferon-alfa/administração & dosagem , Interferon-alfa/uso terapêutico , Masculino , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/uso terapêutico , RNA Viral/sangue , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/uso terapêutico , Ribavirina/administração & dosagem , Ribavirina/uso terapêutico , Doadores de Tecidos , Carga Viral
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