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1.
Phys Chem Chem Phys ; 21(13): 7183-7195, 2019 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-30888381

RESUMO

Cathode materials with highly reactive surfaces and long-term stability are required to achieve high-performance solid oxide fuel cells (SOFCs). In this study, a promising cathode material, La0.6Sr0.4Co0.2Fe0.8O3-δ (LSCF), was prepared as a nanostructured thin film using pulsed laser deposition (PLD) on gadolinia-doped ceria (GDC)-buffered YSZ single crystal substrates having (100) and (111) orientations. Characterization revealed intrinsic differences among the as-grown LSCF thin films in terms of dominant crystalline orientation and nanostructure depending on GDC preparation as well as the YSZ substrate orientation. Evaluation of the oxygen exchange properties using the isotope exchange depth profile method revealed that LSCF thin films grown on (111) GDC/YSZ exhibited higher values of the apparent surface exchange coefficient compared to LSCF thin films grown on (100) GDC/YSZ. However, when subjected to long-term annealing at high temperatures, the former exhibited a stronger tendency to surface segregation as compared to the latter. These behaviors are correlated with the intrinsic properties of LSCF thin films, including the nanostructure, the possible effects attributed to SrO activity, and the stability of perovskite surfaces which would drive surface segregation. These results have implications for tailoring the performance of cathode thin films by understanding the dependence of oxygen exchange properties and surface segregation on driving forces such as surface chemistry and nanostructure.

2.
Neuroscience ; 300: 474-92, 2015 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-26026679

RESUMO

This functional magnetic resonance imaging (fMRI) study investigated the brain regions underlying language task performance in adult second language (L2) learners. Specifically, we identified brain regions where the level of activation was associated with L2 fluency levels. Thirty Japanese-speaking adults participated in the study. All participants were L2 learners of English and had achieved varying levels of fluency, as determined by a standardized L2 English proficiency test, the Versant English Test (Pearson Education Inc., 2011). When participants performed the oral sentence building task from the production tasks administered, the dorsal part of the left inferior frontal gyrus (dIFG) showed activation patterns that differed depending on the L2 fluency levels: The more fluent the participants were, the more dIFG activation decreased. This decreased activation of the dIFG might reflect the increased automaticity of a syntactic building process. In contrast, when participants performed an oral story comprehension task, the left posterior superior temporal gyrus (pSTG) showed increased activation with higher fluency levels. This suggests that the learners with higher L2 fluency were actively engaged in post-syntactic integration processing supported by the left pSTG. These data imply that L2 fluency predicts neural resource allocation during language comprehension tasks as well as in production tasks. This study sheds light on the neural underpinnings of L2 learning by identifying the brain regions recruited during different language tasks across different modalities (production vs. comprehension).


Assuntos
Encéfalo/fisiologia , Compreensão/fisiologia , Multilinguismo , Percepção da Fala/fisiologia , Fala/fisiologia , Adolescente , Adulto , Mapeamento Encefálico , Feminino , Humanos , Testes de Linguagem , Aprendizagem/fisiologia , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Leitura , Adulto Jovem
3.
Intern Med J ; 37(3): 161-7, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17316334

RESUMO

BACKGROUND: The mortality rate for cerebrovascular diseases is much higher in Japan than in North American and West European countries. The primary aim of this study was to elucidate from an epidemiological perspective, the associations between cerebral infarction and demographic factors, medical history and other clinical measurements including pulse wave velocity, a newly introduced non-invasive measurement procedure used to assess aortic stiffness. METHODS: This was a hospital-based, matched case-control study in northern Japan where there is a high incidence of cerebrovascular disease. The study group consisted of 92 matched pairs of cerebral infarction patients (cases) and healthy individuals admitted for a thorough health check-up (controls) at the Southern Tohoku General Hospital in Fukushima Prefecture, Japan. A conditional logistic regression model was used in the statistical analysis. RESULTS: In univariate analyses, 14 variables were significantly associated with cerebral infarction, of which four remained significant in the final multivariate model. These were family history of hypertension (odds ratio (OR) = 8.61), cerebrovascular diseases (OR = 13.70), high-density lipoprotein cholesterol of 40 mg/dL or higher (OR = 0.08), and pulse wave velocity over 1600 cm/s (OR = 2.92). CONCLUSION: Findings from the study indicate that a high pulse wave velocity, in addition to other traditional risk factors, may be associated with a higher risk of cerebral infarction. Further prospective studies are necessary to evaluate the use of this measure as a predictor of the disease.


Assuntos
Aterosclerose/complicações , Velocidade do Fluxo Sanguíneo , Infarto Cerebral/etiologia , Pulso Arterial , Medição de Risco/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Transtornos Cerebrovasculares/complicações , Transtornos Cerebrovasculares/genética , HDL-Colesterol/sangue , Métodos Epidemiológicos , Feminino , Humanos , Hipertensão/complicações , Hipertensão/genética , Modelos Logísticos , Masculino , Prontuários Médicos , Pessoa de Meia-Idade , Valor Preditivo dos Testes
4.
J Epidemiol ; 11(5): 233-7, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11579932

RESUMO

The case subjects were 67 stroke patients (27 males and 40 females, mean age 65.7+/-7.1), who suffered from stroke attack and had participated in annual medical check-up between 1987 and 1988 at Oyabe Public Health Center. The controls, which were adjusted for sex, age and blood pressure level with the case subjects, were selected from participants attending their annual medical check-up in 1987-1988. The serum thiocyanate level of case subjects were significantly higher than that of controls (p<0.05). The usefulness of measurement of serum thiocyanate level as an indicator of smoking status was assessed by using multiple logistic regression analysis adjusting for body mass index, mean blood pressure, and serum cholesterol was found. An odds ratio of 3.00 (95% confidence interval: 1.06-8.48, p<0.05) in cerebral infarction. It is considered that serum thiocyanate may be useful as an indicator of smoking status to assess the relationship with stroke onset, especially for cerebral infarction.


Assuntos
Fumar/sangue , Fumar/epidemiologia , Acidente Vascular Cerebral/sangue , Acidente Vascular Cerebral/epidemiologia , Tiocianatos/sangue , Distribuição por Idade , Idade de Início , Idoso , Biomarcadores/sangue , Pressão Sanguínea , Índice de Massa Corporal , Estudos de Casos e Controles , Colesterol/sangue , Estudos de Coortes , Comorbidade , Intervalos de Confiança , Feminino , Humanos , Japão/epidemiologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Medição de Risco/métodos , Distribuição por Sexo , Acidente Vascular Cerebral/prevenção & controle
5.
Kyobu Geka ; 54(7): 555-9, 2001 Jul.
Artigo em Japonês | MEDLINE | ID: mdl-11452523

RESUMO

Endoscopic transthoracic sympathectomy (ETS) is an efficient, safe, minimally invasive procedure, and requires only a short period of hospitalization. We performed bilateral ETS using a thoracoscope 2 mm in diameter. We performed 120 ETS for the treatment of palmar hyperhidrosis from August 1997 to April 2000. The patient was placed in the semi-sitting position under general anesthesia, one-lung ventilation being used; the operation was performed with 2-mm two-puncture method. The sympathetic chain could be observed through parietal pleura riding on the costovertebral junctions. A 2-mm Kirschner wire was employed as an electrode, and the second and third thoracic sympathetic chains were electro cauterized. A thoracic drain was not used. The needling sites were only 2 mm in size and could be fixed without suture. For the patient, a small scar of this size means virtually no scar. The operative times were from 11 min to 81 min in bilateral ETS. Immediately and dramatic decrease in the sweat excretion in the palms was noted in all patients. The 95% patients were highly satisfied with the results. The commonest side effects were compensatory sweating. This procedure is recommended as the method of choice for the surgical treatments of palmar hyperhidrosis.


Assuntos
Hiperidrose/cirurgia , Simpatectomia/métodos , Toracoscopia , Adolescente , Adulto , Desenho de Equipamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Toracoscópios
6.
J Hum Genet ; 46(6): 330-4, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11393536

RESUMO

The A-to-G mutation at nucleotide 3243 of the mitochondrial tRNA(Leu(UUR)) gene (mt.3243A>G) is associated with both diabetes mellitus and myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS). Recently, this mutation was found in three diabetic subjects with progressive kidney disease, suggesting that it may be a contributing factor in the development of kidney disease in patients with diabetes. The aim of this study was to evaluate the contribution of this mutation to the development of end stage renal disease (ESRD) in patients with diabetes. The study group consisted of 135 patients with diabetes and ESRD. The control group consisted of 92 non-diabetic subjects with ESRD who were receiving hemodialysis. The mt.3243A>G mutation was detected by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). We found the mt.3243A>G mutation in eight patients (8/135; 5.9%), all of whom were initially diagnosed with type II diabetes. Five of the eight patients were subsequently also diagnosed with MELAS. We did not find the mutation in any of the 92 nondiabetic subjects with ESRD. The prevalence of this mutation was 6.5-fold higher in patients with diabetes and ESRD than in those with diabetes alone (8/135 vs 5/550, respectively; chi2 = 13.704; P = 0.0002). The mt.3243A>G mutation may be a contributing genetic factor in the development of ESRD in Japanese patients with diabetes.


Assuntos
Diabetes Mellitus/genética , Falência Renal Crônica/genética , Mutação Puntual , RNA de Transferência de Leucina/genética , RNA/genética , Adulto , Idoso , Sequência de Bases , Primers do DNA/genética , Surdez/complicações , Surdez/genética , Complicações do Diabetes , Nefropatias Diabéticas/genética , Feminino , Humanos , Japão , Falência Renal Crônica/complicações , Síndrome MELAS/complicações , Síndrome MELAS/genética , Masculino , Pessoa de Meia-Idade , Linhagem , RNA Mitocondrial
8.
Environ Health Prev Med ; 6(2): 88-91, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21432242

RESUMO

All residents aged 40 years or more in Oyabe City, Toyama Prefecture, Japan were involved in an annual medical check-up between 1987 and 1988. The cohort was followed and death certificates from cancers were confirmed prospectively. During follow-up to December 31 st, 1994, 100 deaths (28 gastric, 17 lung and 55 other cancers) from cancers occurred, and these subjects were included in this study as the case group. Subjects in the control group, matched for gender and age with the cases, were selected randomly from participants whose serum samples had been stocked during annual medical check-up. The concentration of serum thiocyanate in all (79.8 µmol/l), gastric (86.7 µmol/l) and lung (90.0 µmol/l) cancer patients were significantly higher than that of relevant controls (64.3 µmol/l, 59.0 µmol/l and 61.0 µmol/l, respectively; and p<0.001, p<0.001 and p<0.05, respectively). After adjusting for BMI, blood pressure and total serum cholesterol, the results of multiple logistic regression analysis showed that the risk of all cancers (OR=3.40, 95% confidence interval (95% Cl): 1.67-6.96, p<0.01), gastric cancer (OR=7.98, 95% CI: 1.91-33.34, p<0.05) and lung cancer (OR=8.83, 95% CI: 1.19-65.65, p<0.05) were elevated significantly with logarithm transformed values of serum thiocyanate increased. The present findings suggested that in epidemiological studies confirmation of smoking status with biomarkers such as serum thiocyanate may be important, although considering the small sample size, a relatively weaker risk to interested factors rather than the strong relationship between smoking and cancer was noted.

9.
Kyobu Geka ; 48(4): 290-4, 1995 Apr.
Artigo em Japonês | MEDLINE | ID: mdl-7715113

RESUMO

A rapid and significant vasodepressor effect was obtained during acute stage before and after surgery on aortic aneurysm with continuous antihypertensive therapy using nicardipine hydrochloride. Twenty patients were treated; 6 patients had an acute dissecting aneurysm of the aorta, 8 were postoperative cases following resection of the thoracic aortic aneurysm, and 6 were postoperative cases of the abdominal aortic aneurysm. Nicardipine hydrochloride is easy to administer, has few side effects, and was found to be effective as antihypertensive therapy before and after surgery. The use of nicardipine hydrochloride has therefore been adopted by this unit as part of the treatment protocol for these patients.


Assuntos
Aneurisma da Aorta Torácica/cirurgia , Dissecção Aórtica/cirurgia , Hipertensão/prevenção & controle , Nicardipino/uso terapêutico , Complicações Pós-Operatórias/prevenção & controle , Adulto , Idoso , Dissecção Aórtica/fisiopatologia , Aneurisma da Aorta Torácica/fisiopatologia , Feminino , Frequência Cardíaca/efeitos dos fármacos , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Nicardipino/farmacologia
10.
Cytokine ; 4(1): 12-7, 1992 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1617155

RESUMO

Rat gro/melanoma growth-stimulating activity is a dimer composed of two identical subunits. Each subunit consists of 72 amino-acid residues and contains two disulfide bridges. In order to obtain information on the structure responsible for chemotactic activity, various fragments of gro were prepared and tested for their ability to induce chemotaxis. None of the fragments corresponding to residues 1-6, 1-21, 12-31, 36-50 or 52-72 was active as a chemoattractant. Reduced and carboxymethylated gro as well as the tryptic peptide consisting of three peptides, residues 9-21, 28-45 were and 49-61, linked by two disulfide bonds Cys-9-Cys-35 and Cys-11-Cys-51, were inactive. Also, these, peptides did not inhibit the chemotactic activity of gro. Rat gro lacking the N-terminal 6 residues had a reduced activity and the one lacking the C-terminal Lys was as active as intact gro. Therefore, an almost entire portion of the molecule including disulfide cross-links is required for chemotactic activity.


Assuntos
Quimiocinas CXC , Fatores Quimiotáticos/farmacologia , Quimiotaxia de Leucócito/efeitos dos fármacos , Substâncias de Crescimento/farmacologia , Peptídeos e Proteínas de Sinalização Intercelular , Proteínas de Neoplasias/farmacologia , Neutrófilos/efeitos dos fármacos , Fragmentos de Peptídeos/farmacologia , Sequência de Aminoácidos , Animais , Quimiocina CXCL1 , Fatores Quimiotáticos/química , Endopeptidases/metabolismo , Substâncias de Crescimento/química , Dados de Sequência Molecular , Proteínas de Neoplasias/química , Fragmentos de Peptídeos/síntese química , Fragmentos de Peptídeos/química , Ratos , Relação Estrutura-Atividade
11.
Kyobu Geka ; 44(7): 558-61, 1991 Jul.
Artigo em Japonês | MEDLINE | ID: mdl-1886316

RESUMO

Six cases of lung cancer combined with the disease which has needed semi-emergency operation, two cases of unstable angina, two of ileus due to colon cancer, one of impending rupture of abdominal aortic aneurysm and one of purulent cholecystitis with cholelithiasis, were discussed. Mean age was 62.0 years (range, 36 to 73); four were male and two were female. Case 1 and 2 were admitted with anterior chest pain, Case 3 with lumbago and abdominal pain, Case 4 and 5 with an abnormal shadow on chest x-ray film and Case 6 with abdominal pain. Of the two with unstable angina, one was operated on with right upper lobectomy during the first months after aorto-coronary bypass. Of the two with colon cancer, one was operated on with right upper lobectomy during about 5 weeks after right hemi-colectomy. Case 3 with abdominal aortic aneurysm operated on with left upper lobectomy during 4 weeks after replacement of abdominal aorta. Case 4 with cholecystitis was operated on with left pneumonectomy during about 3 weeks after cholecystectomy. The postoperative course of 4 cases and the post-chemotherapy condition of 2 cases were uneventful.


Assuntos
Adenocarcinoma/complicações , Angina Instável/cirurgia , Ponte de Artéria Coronária , Neoplasias Pulmonares/complicações , Adenocarcinoma/cirurgia , Adulto , Idoso , Angina Instável/complicações , Aorta Abdominal , Ruptura Aórtica/complicações , Ruptura Aórtica/cirurgia , Colecistite/complicações , Colecistite/cirurgia , Neoplasias do Colo/patologia , Neoplasias do Colo/cirurgia , Emergências , Feminino , Humanos , Neoplasias Pulmonares/cirurgia , Masculino , Pessoa de Meia-Idade , Neoplasias Primárias Múltiplas
12.
Kyobu Geka ; 44(4): 334-6, 1991 Apr.
Artigo em Japonês | MEDLINE | ID: mdl-2038166

RESUMO

Esophageal duplication cyst associated with pericardial defect in a 57-year-old man is reported. Differential diagnosis was very difficult in the preoperative examination. The tumor was a cyst and its wall was a perfect replica of normal esophagus e.g. esophageal duplication, and total left pericardial defect also was found at the operation. There was no malignant or inflammation findings in the excised specimens. The association of esophageal duplication cyst associated with pericardial defect is very rare.


Assuntos
Cisto Esofágico/cirurgia , Pericárdio/anormalidades , Cisto Esofágico/complicações , Humanos , Masculino , Pessoa de Meia-Idade
15.
No Shinkei Geka ; 16(11): 1311-5, 1988 Oct.
Artigo em Japonês | MEDLINE | ID: mdl-3062482

RESUMO

A case of transorbital intracranial foreign bodies due to windshield impact was reported. A 17-year-old man was admitted to our department after he had his face injured in a traffic accident. He was fully conscious, and had no neurological deterioration except for a disturbance in his left external ocular movement. Plain skull X-rays and a plain CT revealed foreign bodies in the left orbit and the left frontal lobe. Combined surgery, through the orbit and the subfrontal approach, was performed to remove many foreign bodies (crushed windshield glass). His external ocular movement returned to normal postoperatively. There were no complications of meningitis and liquorrhea, and he was discharged without any neurological deficiency. The law, enacted in 1988, obliges the use of high penetration resistant (H.P.R.) laminated windshield in all new cars in Japan. But many motor cars equipped with partially enhanced windshields are still in use. It should be noted that partially enhanced windshields cause more severe injuries than H.P.R. laminated ones.


Assuntos
Acidentes de Trânsito , Encéfalo , Corpos Estranhos/cirurgia , Órbita , Adolescente , Corpos Estranhos/diagnóstico por imagem , Vidro , Humanos , Masculino , Tomografia Computadorizada por Raios X
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