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1.
Clin Radiol ; 77(11): 855-863, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36055826

RESUMO

AIM: To evaluate the usefulness of synthetic magnetic resonance imaging (MRI) performed before the initiation of neoadjuvant chemotherapy (NAC) in predicting whether breast cancers can achieve a pathological complete response (pCR) after the completion of NAC. MATERIALS AND METHODS: This retrospective study investigated 37 consecutive patients with 39 breast cancers (pCR: 14, and non-pCR: 25) who underwent dynamic contrast-enhanced (DCE)-MRI and synthetic MRI before the initiation of NAC. Using synthetic MRI images, quantitative values (T1 and T2 relaxation times, proton density [PD] and their standard deviations [SD]) were obtained in breast lesions, before (Pre-T1, Pre-T2, Pre-PD, SD of Pre-T1, SD of Pre-T2, SD of Pre-PD) and after (Gd-T1, Gd-T2, Gd-PD, SD of Gd-T1, SD of Gd-T2, SD of Gd-PD) contrast agent injection. The aforementioned quantitative values and several morphological features that were identified on DCE-MRI were compared between pCR and non-pCR. RESULTS: Multivariate analyses revealed that the SD of Pre-T2 (p=0.038) was significant and was an independent predictor of pCR, with an area under the receiver operating characteristics curve of 0.829. The sensitivity, specificity, and accuracy of the SD of Pre-T2 with an optimal cut-off value of 11.5 were 71.4%, 80%, and 76.3%, respectively. CONCLUSIONS: The SD of Pre-T2 obtained from synthetic MRI was used successfully to predict those breast cancers that would achieve a pCR after the completion of NAC; however, these results are preliminary and need to be verified by further studies.


Assuntos
Neoplasias da Mama , Terapia Neoadjuvante , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Meios de Contraste/uso terapêutico , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Terapia Neoadjuvante/métodos , Prótons , Estudos Retrospectivos , Resultado do Tratamento
2.
Clin Radiol ; 75(5): 398.e1-398.e8, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32019671

RESUMO

AIM: To evaluate the utility of synthetic magnetic resonance imaging (MRI) of the breast in predicting the Ki-67 status in patients with oestrogen receptor (ER)-positive breast cancer. MATERIALS AND METHODS: Forty-nine patients with 50 histopathologically proven breast cancers who underwent additional synthetic MRI were enrolled in the present study. Using synthetic MRI images, T1 and T2 relaxation times and their standard deviations (SD) in the breast lesions before (T1-Pre, T2-Pre, PD-Pre, SD of T1-Pre, SD of T2-Pre, SD of PD-Pre) and after (T1-Gd, T2-Gd, PD-Gd, SD of T1-Gd, SD of T2-Gd, SD of PD-Gd) contrast agent injection were obtained. These quantitative values were compared between the low Ki-67 expression (<14%) lesions (low-proliferation group: n=23) and high Ki-67 expression (≥14%) lesions (high-proliferation group: n=27). RESULTS: The univariate analysis showed that the SD of T1-Gd (p<0.001) and T2-Gd (p=0.042) were significantly higher in the high-proliferation group than in the low-proliferation group. Multivariate analysis further showed that the SD of T1-Gd was a significant and independent predictor of Ki-67 expression, with an area under the receiver operating characteristic (AUROC) curve of 0.885. The sensitivity, specificity, and accuracy of the SD of T1-Gd with an optimal cut-off value of 98.5 were 77.8%, 87%, and 82%, respectively. CONCLUSION: The SD of T1-Gd obtained from synthetic MRI was useful to predict Ki-67 status.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/metabolismo , Antígeno Ki-67/metabolismo , Imageamento por Ressonância Magnética/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/cirurgia , Meios de Contraste , Estudos de Viabilidade , Feminino , Humanos , Aumento da Imagem/métodos , Biópsia Guiada por Imagem , Pessoa de Meia-Idade , Receptores de Estrogênio/metabolismo , Estudos Retrospectivos , Sensibilidade e Especificidade
3.
Clin Radiol ; 74(9): 697-701, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31196565

RESUMO

AIM: To evaluate the effect of augmented training datasets in a deep convolutional neural network (DCNN) used for detecting abnormal chest radiographs. MATERIALS AND METHODS: Chest radiographs were corrected to conform to a DCNN dataset, with 288 abnormal and 447 normal radiographs. The radiographic images were divided into training and validation sets (441, 60%), and a test set (294, 40%). The training and validation sets were augmented to generate a total of 12,789 training and validation images. The augmentation consisted of operations such as rotation, horizontal and vertical flipping, Gaussian blur, and brightness variation, either alone or combined. The DCNN performed binary classification of the images as being abnormal or normal chest radiographs, and accuracy was used as measure to assess the model performance. RESULTS: The accuracy of the DCNN trained with the augmented dataset tended to be higher than that of the DCNN trained with the non-augmented dataset. The augmented datasets combining rotation and horizontal flipping had a high accuracy of 0.91, showing the highest accuracy among the applied augmentation techniques and combinations. CONCLUSION: Augmentation of training datasets can improve the performance of DCNN for radiographic image classification depending on the applied augmentation technique.


Assuntos
Redes Neurais de Computação , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Radiografia Torácica , Humanos , Estudos Retrospectivos
4.
Clin Radiol ; 72(10): 828-834, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28615141

RESUMO

AIM: To examine the diagnostic capabilities of feature-tracking cardiovascular magnetic resonance (FT-CMR), tagged cine magnetic resonance (MR), and wall thickening (WT) analyses to detect infarcted segments in patients with established myocardial infarction (MI). MATERIALS AND METHODS: Twenty patients with established MI were selected retrospectively and the peak endocardial circumferential strain (CS) was quantified based on the 16-segment model. According to CMR with late gadolinium enhancement, segments were categorised as transmural MI, subendocardial MI, and no MI. RESULTS: A total of 320 segments (62 transmural MI, 50 subendocardial MI, and 208 no MI) were analysed. Peak endocardial CS was significantly lower for transmural MI compared with subendocardial MI (p<0.05) and no MI (p<0.001). Cut-off values of -11.2% for CS by FTCMR, -10.9% for CS by tagged MR, and 23.8% for %WT, differentiated between infarcted and non-infarcted segments with a sensitivity of 72%, 71%, and 56%; specificity of 71%, 75%, and 67%; accuracy of 72%, 73%, and 63%; positive predictive value of 57%, 60%, and 48%; negative predictive value of 83%, 83%, and 74%; and an area-under-the-curve of 0.77, 0.79, and 0.64, respectively. CONCLUSIONS: FT-CMR was diagnostically superior to %WT, and could differentiate between subendocardial and transmural MI. Unlike tagged MR, FT-CMR did not require the acquisition of additional sequences.


Assuntos
Imageamento por Ressonância Magnética/métodos , Infarto do Miocárdio/diagnóstico por imagem , Idoso , Diagnóstico Diferencial , Feminino , Coração/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/patologia , Miocárdio/patologia , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade
5.
Skin Res Technol ; 22(1): 20-4, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25786330

RESUMO

BACKGROUND/PURPOSE: Perceived age may be a better predictor of mortality rate than chronological age. We have demonstrated that perceived age was a significant biomarker for carotid atherosclerosis in Japanese. However, it remains to be determined which skin parameter is associated with atherosclerosis. The purpose of this study is to analyze the relationship between 10 facial skin-aging parameters and atherosclerosis in 169 middle-aged to elderly Japanese women who participated. METHODS: Facial photographs were taken under a shadowless lamp from three directions using a high-resolution digital camera. The digital images of each subject were analyzed using computer software and various parameters of skin aging such as pigmentation, wrinkles, and skin color were quantified. Carotid intima-media thickness (IMT) and brachial-ankle pulse wave velocity (baPWV) were measured as indices for atherosclerosis. RESULTS: Facial pigmentation showed a significant correlation with carotid IMT, even after correction for age (r = 0.13, P = 0.03), and with visceral fat area. Stepwise regression analysis indicated that facial pigmentation was associated with carotid IMT via visceral fat area. CONCLUSION: Facial pigmentation may be a useful biomarker for carotid atherosclerosis in Japanese women.


Assuntos
Doenças das Artérias Carótidas/diagnóstico , Doenças das Artérias Carótidas/epidemiologia , Face/patologia , Pigmentação da Pele , Pele/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores , Colorimetria/métodos , Feminino , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Japão/epidemiologia , Pessoa de Meia-Idade , Fotografação/métodos , Prevalência , Valores de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
6.
Mol Psychiatry ; 19(11): 1220-6, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24637425

RESUMO

Dioxin levels in the breast milk of mothers residing near a contaminated former airbase in Vietnam remain much higher than in unsprayed areas, suggesting high perinatal dioxin exposure for their infants. The present study investigated the association of perinatal dioxin exposure with autistic traits in 153 3-year-old children living in a contaminated area in Vietnam. The children were followed up from birth using the neurodevelopmental battery Bayley-III. The high-2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) exposed groups (⩾3.5 pg per g fat) showed significantly higher Autism Spectrum Rating Scale (ASRS) scores for both boys and girls than the mild-TCDD exposed groups, without differences in neurodevelopmental scores. In contrast, the high total dioxin-exposed group, indicated by polychlorinated dibenzo-p-dioxins/furans (PCDDs/Fs)--the toxic equivalents (TEQ) levels⩾17.9 pg-TEQ per g fat, had significantly lower neurodevelopmental scores than the mild-exposed group in boys, but there was no difference in the ASRS scores. The present study demonstrates a specific impact of perinatal TCDD on autistic traits in childhood, which is different from the neurotoxicity of total dioxins (PCDDs/Fs).


Assuntos
Transtorno Autístico/epidemiologia , Desenvolvimento Infantil , Leite Humano/química , Dibenzodioxinas Policloradas/efeitos adversos , Dibenzodioxinas Policloradas/análise , Benzofuranos/efeitos adversos , Benzofuranos/análise , Desenvolvimento Infantil/efeitos dos fármacos , Pré-Escolar , Estudos de Coortes , Dioxinas/efeitos adversos , Dioxinas/análise , Relação Dose-Resposta a Droga , Feminino , Seguimentos , Humanos , Masculino , Exposição Materna , Escalas de Graduação Psiquiátrica , Fatores Sexuais , Vietnã/epidemiologia
7.
Eur J Nutr ; 53(1): 251-8, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23575771

RESUMO

PURPOSE: This cohort study investigated the association between sugar-sweetened beverage (SSB) and diet soda consumption and the incidence of type 2 diabetes in Japanese men. METHODS: The participants were 2,037 employees of a factory in Japan. We measured consumption of SSB and diet soda using a self-administered diet history questionnaire. The incidence of diabetes was determined in annual medical examinations over a 7-year period. Hazard ratios (HRs) with 95 % confidence intervals (CIs) for diabetes were estimated after adjusting for age, body mass index, family history, and dietary and other lifestyle factors. RESULTS: During the study, 170 participants developed diabetes. The crude incidence rates (/1,000 person-years) across participants who were rare/never SSB consumers, <1 serving/week, ≥ 1 serving/week and <1 serving/day, and ≥ 1 serving/day were 15.5, 12.7, 14.9, and 17.4, respectively. The multivariate-adjusted HR compared to rare/never SSB consumers was 1.35 (95 % CI 0.80-2.27) for participants who consumed ≥ 1 serving/day SSB. Diet soda consumption was significantly associated with the incident risk of diabetes (P for trend = 0.013), and multivariate-adjusted HRs compared to rare/never diet soda consumers were 1.05 (0.62-1.78) and 1.70 (1.13-2.55), respectively, for participants who consumed <1 serving/week and ≥ 1 serving/week. CONCLUSIONS: Consumption of diet soda was significantly associated with an increased risk for diabetes in Japanese men. Diet soda is not always effective at preventing type 2 diabetes even though it is a zero-calorie drink.


Assuntos
Bebidas , Bebidas Gaseificadas , Diabetes Mellitus Tipo 2/prevenção & controle , Adoçantes Calóricos/administração & dosagem , Adulto , Povo Asiático , Índice de Massa Corporal , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/epidemiologia , Dieta , Inquéritos sobre Dietas , Ingestão de Energia , Seguimentos , Humanos , Incidência , Japão/epidemiologia , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Inquéritos e Questionários
8.
Eur J Neurol ; 20(5): 860-2, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23020117

RESUMO

BACKGROUND AND PURPOSE: A recent genome-wide association study has successfully identified several genetic variations in the Chr17q25 locus as susceptible genotypes for white matter hyperintensities. We report the first replication study in subjects of non-European origin. We also investigated possible associations with other asymptomatic cerebrovascular diseases and cognitive function. METHODS: Study subjects were 1190 general Japanese persons (66.0 ± 8.9 years old). Asymptomatic cerebrovascular damage, including lacunar infarctions, microbleeds, periventricular hyperintensity and deep and subcortical white matter hyperintensity (DSWMH), was evaluated by brain magnetic resonance imaging. RESULTS: A polymorphism rs3744028 was significantly associated with DSWMH grade (P = 0.015) but not periventricular hyperintensity, lacunar infarction, and microbleeds. Although age, hypertension, insulin resistance, B-type natriuretic peptide, and carotid atherosclerosis were also correlated with DSWMH, association of the genotype was independent of these environmental risk factors. In contrast, the risk allele had a protective effect against reduced cognitive function. CONCLUSION: Susceptibility of the 17q25 locus may be conserved beyond ethnic differences. Genetic variants may have bipolar effects on brain histological and functional changes.


Assuntos
Transtornos Cerebrovasculares/genética , Transtornos Cerebrovasculares/patologia , Cromossomos Humanos Par 17/genética , Transtornos Cognitivos/genética , Transtornos Cognitivos/patologia , Fibras Nervosas Mielinizadas/patologia , Idoso , Povo Asiático/genética , Povo Asiático/psicologia , Transtornos Cerebrovasculares/diagnóstico , Feminino , Humanos , Masculino , Neuroimagem/psicologia , Polimorfismo de Nucleotídeo Único/genética
9.
Environ Toxicol ; 28(1): 21-30, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21384493

RESUMO

Chlorinated benz[a]anthracenes (Cl-BaA) are halogenated aromatic compounds (typified by dioxins) found in the environment at relatively high concentrations. Fischer 344 rats were intragastrically administered 0, 1, or 10 mg of Cl-BaA or its parent compound benz[a]anthracene (BaA) per kg of body weight for 14 consecutive days. Both chemicals at 10 mg/kg/day inhibited the gain in body weight, and consequent increase in relative liver weight. Hepatic gene expression of cytochrome P450 (CYP) 1A1, 1A2, and 1B1 was significantly stimulated by administration of BaA (10 mg/kg/day) compared with the control. After administration of Cl-BaA, only the CYP1A2 gene was significantly induced, even at the lower dosage; CYP1A1 and 1B1 mRNA levels remained unchanged in Cl-BaA-treated rats compared with controls. To elucidate the role of such Cl-BaA exposure and induced CYPs at toxicity onset, we investigated the mutagenicity of BaA and Cl-BaA using Salmonella typhimurium TA98 and TA100. BaA and Cl-BaA at 10 µg/plate produced positive results in both strains in the presence of rat S-9. Incubation of Cl-BaA with recombinant rat CYP1A2 produced a significantly higher number of revertant colonies in TA98 and TA100 than in controls, but no such change was observed for BaA. In conclusion, BaA changes its own physiological and toxicological actions by its chlorination; (1) daily exposure to Cl-BaA selectively induces hepatic CYP1A2 in rats and (2) Cl-BaA induces frameshift mutations in the presence of CYP1A2, although BaA does not exert mutagenicity. This indicates that CYP1A2 may metabolize Cl-BaA to active forms.


Assuntos
Benzo(a)Antracenos/toxicidade , Fígado/efeitos dos fármacos , Mutagênicos/toxicidade , Salmonella typhimurium/efeitos dos fármacos , Animais , Hidrocarboneto de Aril Hidroxilases/metabolismo , Citocromo P-450 CYP1A1/metabolismo , Citocromo P-450 CYP1A2 , Citocromo P-450 CYP1B1 , Citocromos/metabolismo , Mutação da Fase de Leitura , Regulação da Expressão Gênica/efeitos dos fármacos , Halogenação , Fígado/metabolismo , Masculino , Testes de Mutagenicidade , Ratos , Ratos Endogâmicos F344 , Salmonella typhimurium/metabolismo
10.
Horm Metab Res ; 44(13): 966-74, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22821008

RESUMO

We conducted a longitudinal study to investigate whether increased serum gamma-glutamyltransferase independently predicts subsequent development of hyperuricemia. The study participants included 3,310 Japanese men without hyperuricemia, aged 20-54 years. The participants had annual heath examinations for 6 years to assess incident hyperuricemia (defined as serum uric acid>416.4 µmol/l and/or taking medication for hyperuricemia). The risk of incident hyperuricemia was compared in participants grouped according to their baseline serum gamma-glutamyltransferase level. During follow-up, there were 529 incident cases of hyperuricemia. A positive, dose-response relationship was observed between serum gamma-glutamyltransferase and the risk of incident hyperuricemia. The hazard ratios (95% confidence intervals) for hyperuricemia, compared with a serum gamma-glutamyltransferase level ≤19 U/l, were 1.32 (1.05-1.67) for 20-39 U/l, 1.28 (0.90-1.83) for 40-59 U/l, 1.56 (0.98-2.47) for 60-79 U/l, and 1.57 (1.02-2.41) for ≥80 U/l after adjustment for baseline serum uric acid, creatinine, total cholesterol, and glycated hemoglobin levels, ln(serum alanine aminotransferase), age, systolic blood pressure, medications for hypertension, hypercholesterolemia, and diabetes, body mass index, and smoking and exercise habits. A similar positive relationship was observed regardless of the presence or absence of alcohol drinking, obesity, metabolic disorders (any combination of hypertension, hypercholesterolemia and/or diabetes), or clinically high serum aminotransferases, without evidence of a significant interaction between increased serum gamma-glutamyltransferase and risk factors for incident hyperuricemia. These findings indicate that increased serum gamma-glutamyltransferase is an independent predictor of subsequent development of hyperuricemia.


Assuntos
Hiperuricemia/etiologia , gama-Glutamiltransferase/sangue , Adulto , Humanos , Hiperuricemia/enzimologia , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Risco , Adulto Jovem
11.
Nutr Metab Cardiovasc Dis ; 22(11): 989-96, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21421297

RESUMO

BACKGROUND AND AIMS: Since there is little information derived from prospective studies on the amount of alcohol drinking required to induce hyperuricaemia, we attempted to address this issue in a Japanese population. METHODS AND RESULTS: A total of 3310 Japanese men aged 20-54 years that were free of hyperuricaemia were classified according to their alcohol intake per week at baseline. Incident hyperuricaemia, defined as >7.0 mg/dl and/or taking medication for hyperuricaemia, was assessed through annual heath examinations for 6 years after the baseline examination. During follow-up, 529 incident cases of hyperuricaemia occurred. There was a positive, dose-response relationship between alcohol intake and the risk of incident hyperuricaemia. The hazard ratio (95% confidence interval) for hyperuricaemia in drinkers compared with non-drinkers was 1.10 (0.85-1.42) for <10.0 drinks/week, 1.40 (1.07-1.84) for 10.0-19.9 drinks/week, 1.64 (1.23-2.21) for 20.0-29.9 drinks/week and 1.98 (1.40-2.80) for ≥30.0 drinks/week (one drink contained 11.5 g of ethanol) after adjusting for age, baseline serum uric acid, body mass index, smoking habits, exercise habits, serum creatinine, blood pressure, serum cholesterol and blood glucose. The fraction of hyperuricaemia in the population attributable to alcohol intake was 21.6%. A clear dose-response pattern was observed for both beer and sake, when the consumption of these two beverages was analysed separately. CONCLUSION: Habitual alcohol intake significantly contributed to the development of hyperuricaemia in Japanese men, regardless of type of alcoholic beverage consumed. Therefore, it is essential to reduce excessive alcohol intake to prevent and manage hyperuricaemia.


Assuntos
Consumo de Bebidas Alcoólicas/epidemiologia , Povo Asiático , Hiperuricemia/epidemiologia , Adulto , Bebidas Alcoólicas/efeitos adversos , Cerveja/efeitos adversos , Índice de Massa Corporal , Seguimentos , Humanos , Incidência , Japão/epidemiologia , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Atividade Motora , Modelos de Riscos Proporcionais , Estudos Prospectivos , Medição de Risco , Fatores de Risco , Fumar , Inquéritos e Questionários , Ácido Úrico/sangue , Adulto Jovem
12.
Nat Med ; 6(1): 96-9, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10613832

RESUMO

Hepatocellular carcinoma (HCC) is one of the most common cancers in Asia and Africa, where hepatitis virus infection and exposure to specific liver carcinogens are prevalent. Although inactivation of some tumor suppressor genes such as p53 and p16INK4Ahas been identified, no known oncogene is commonly activated in hepatocellular carcinomas. Here we have isolated genes overexpressed in hepatocellular carcinomas by cDNA subtractive hybridization, and identified an oncoprotein consisting of six ankyrin repeats (gankyrin). The expression of gankyrin was increased in all 34 hepatocellular carcinomas studied. Gankyrin induced anchorage-independent growth and tumorigenicity in NIH/3T3 cells. Gankyrin bound to the product of the retinoblastoma gene (RB1), increasing its phosphorylation and releasing the activity of the transcription factor E2F-1. Gankyrin accelerated the degradation of RB1 in vitro and in vivo, and was identical to or interacted with a subunit of the 26S proteasome. These results demonstrate the importance of ubiquitin-proteasome pathway in the regulation of cell growth and oncogenic transformation, and indicate that gankyrin overexpression contributes to hepatocarcinogenesis by destabilizing RB1.


Assuntos
Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Fígado/metabolismo , Proteínas Oncogênicas/metabolismo , Complexo de Endopeptidases do Proteassoma , Proteína do Retinoblastoma/metabolismo , Células 3T3 , Animais , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Divisão Celular , Clonagem Molecular , Genes Reporter , Genes do Retinoblastoma , Células HeLa , Humanos , Cinética , Fígado/patologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Camundongos , Camundongos Nus , Proteínas Oncogênicas/genética , Peptídeo Hidrolases/metabolismo , Proteínas Proto-Oncogênicas , Proteínas Recombinantes de Fusão/biossíntese , Transplante Heterólogo , Células Tumorais Cultivadas
13.
Artigo em Inglês | MEDLINE | ID: mdl-19861508

RESUMO

The traditional Japanese medicine rikkunshito ameliorates the nitric oxide-associated delay in gastric emptying. Whether rikkunshito affects gastric motility associated with 5-hydroxytryptamine (serotonin: 5-HT) receptors or dopamine receptors is unknown. We examined the effects of rikkunshito on the delay in gastric emptying induced by 5-HT or dopamine using the phenol red method in male Wistar rats. 5-HT (0.01-1.0 mg kg(-1), i.p.) dose dependently delayed gastric emptying, similar to the effect of the 5-HT(3) receptor agonist 1-(3-chlorophenyl) biguanide (0.01-1.0 mg kg(-1), i.p.). Dopamine also dose dependently delayed gastric emptying. The 5-HT(3) receptor antagonist ondansetron (0.04-4.0 mg kg(-1)) and rikkunshito (125-500 mg kg(-1)) significantly suppressed the delay in gastric emptying caused by 5-HT or 1-(3-chlorophenyl) biguanide. Hesperidin (the most active ingredient in rikkunshito) suppressed the 5-HT-induced delayed gastric emptying in a dose-dependent manner, the maximum effect of which was similar to that of ondansetron (0.4 mg kg(-1)). The improvement obtained by rikkunshito or ondansetron in delaying gastric emptying was completely blocked by pretreatment with atropine. Rikkunshito appears to improve delay in gastric emptying via the antagonistic action of the 5-HT(3) receptor pathway.

14.
Diabetologia ; 53(9): 1894-902, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20502862

RESUMO

AIMS/HYPOTHESIS: Little is known about the relationship between the HOMA of insulin resistance (HOMA-IR) and the risk of cardiovascular events in Asian populations, which have lower levels of HOMA-IR than Western populations. Accordingly, we determined the predictive value of HOMA-IR for cardiovascular risk in a Japanese population that was apparently free of diabetes, addressing whether insulin resistance itself increases cardiovascular risk independently of other relevant metabolic disorders. METHODS: We followed 2,548 non-diabetic men aged 35 to 59 years for 11 years. The hazard ratios for the incidence of cardiovascular events due to increased HOMA-IR were estimated using a Cox proportional hazards model that was adjusted for potential confounding factors. RESULTS: The multivariate-adjusted hazard ratio for cardiovascular events compared with the first quartile of HOMA-IR (or=1.52). The hazard ratio associated with a one SD (0.61) increment in log-transformed HOMA-IR was 1.51 (1.13-2.02). A similar positive relationship was observed for coronary events and stroke. In addition, the relationship between HOMA-IR and cardiovascular risk was broadly similar in participants with and without hypertension, dyslipidaemia (elevated triacylglycerol and/or reduced HDL-cholesterol), abdominal obesity and current smoking. CONCLUSIONS/INTERPRETATION: Increased HOMA-IR predicted subsequent cardiovascular events in non-diabetic Japanese men. The association was independent of traditional cardiovascular risk factors and other relevant metabolic disorders.


Assuntos
Doenças Cardiovasculares/epidemiologia , Resistência à Insulina/fisiologia , Modelos de Riscos Proporcionais , Adulto , Povo Asiático , Doença das Coronárias/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Acidente Vascular Cerebral/epidemiologia
15.
Diabet Med ; 26(8): 753-9, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19709143

RESUMO

AIMS: This study investigated the relationship between waist circumference and the subsequent incidence of Type 2 diabetes and the association with insulin resistance and pancreatic B-cell function in relatively lean Japanese individuals. METHODS: The study participants were 3992 employees (2533 men and 1459 women, aged 35-55 years) of a metal-products factory in Japan. The incidence of diabetes was determined in annual medical examinations during an 8-year follow-up. We calculated age- and sex-adjusted hazard ratios (HRs) according to the sex-specific quintile of waist circumference at baseline. Differences in baseline insulin resistance [homeostatis model assessment (HOMA)-IR] and pancreatic B-cell function (HOMA-B) were compared between participants who developed diabetes and those who did not. RESULTS: During the follow-up, 218 participants developed diabetes. Age- and sex-adjusted HRs across the quintiles of waist circumference were 1.78, 1.00 (reference), 1.59, 3.11 and 3.30, respectively (P for trend, < 0.0001). The HR for the lowest quintile was significantly higher than that for the second quintile. Among participants with waist circumference of the lowest quintile, HOMA-B was lower in those who developed diabetes than in those who did not [33.1 (24.1-45.0) vs. 54.3 (37.9-74.6) median (interquartile range), P < 0.0001], but HOMA-IR did not differ between these groups. CONCLUSIONS: There was a J-shaped relationship between waist circumference and subsequent risk for Type 2 diabetes in relatively lean Japanese individuals; lower pancreatic B-cell function may also increase the risk of diabetes in very lean Japanese people. Diabet. Med. 26, 753-759 (2009).


Assuntos
Povo Asiático/etnologia , Diabetes Mellitus Tipo 2/etnologia , Resistência à Insulina/fisiologia , Células Secretoras de Insulina/fisiologia , Magreza/etnologia , Circunferência da Cintura/etnologia , Adulto , Índice de Massa Corporal , Métodos Epidemiológicos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
17.
Clin Exp Med ; 7(3): 108-14, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17972053

RESUMO

The present study examined the relationship between genetic combinations of the C1429T polymorphism in the G-protein beta-3 subunit (GNB3) gene and the A1330V polymorphism in the low-density lipoprotein receptor-related protein 5 (LRP5) gene and the risk of hypercholesterolaemia in Japanese workers. The present study included observations from 1997 to 2002 in 927 males and 662 females who were not hypercholesterolaemic on entry. The endpoint was the development of hypercholesterolaemia, defined as a total cholesterol level > or =240 mg/dl. The odds ratios for the combination of polymorphisms were calculated using pooled logistic regression analyses that incorporated other potential factors into the model. The odds ratios in males and females with GNB3/1429TT and LRP5/1330VV or AV genotypes were 4.17 compared to males with the 1429CT or TT and 1330AA genotypes and 3.53 compared to females with the 1429CC, CT or TT and 1330AA genotypes. Assuming these effects were a mere addition of two independent effects, the odds ratios for both GNB3/1429TT and LRP5/1330VV or AV were estimated to be 3.27 for males and 1.42 for females. Therefore, the synergic effects were shown to be 1.28 times in males (not significant) and 2.49 times in females (P<0.05 by bootstrap method). These results provide clear evidence that the genetic combination has a synergic effect. This study indicates that the combination of GNB3/C1429T and LRP5/A1330V is a very useful marker for predicting the development of hypercholesterolaemia in the general Japanese population.


Assuntos
Proteínas Heterotriméricas de Ligação ao GTP/genética , Hipercolesterolemia/genética , Proteínas Relacionadas a Receptor de LDL/genética , Polimorfismo Genético , Adulto , Feminino , Genótipo , Humanos , Hipercolesterolemia/epidemiologia , Hipercolesterolemia/etiologia , Japão/epidemiologia , Proteína-5 Relacionada a Receptor de Lipoproteína de Baixa Densidade , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco
18.
Obes Sci Pract ; 3(2): 162-170, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28702211

RESUMO

OBJECTIVE: This study investigated the relationship between frequency of skipping breakfast and annual changes in body mass index (BMI) and waist circumference (WC). METHODS: The participants were 4,430 factory employees. BMI and WC were measured repeatedly at annual medical examinations over a 5-year period. The association between frequency of skipping breakfast at the baseline examination and annual changes in anthropometric indices was evaluated using the generalized estimating equation method. RESULTS: The mean (standard deviation) BMI was 23.3 (3.0) kg m-2 for men and 21.9 (3.6) kg m-2 for women; and the mean WC was 82.6 (8.7) cm for men and 77.8 (9.8) cm for women. During the follow-up period, mean BMI increased by 0.2 kg m-2 for men and women, and mean WC increased by 1.1 cm for men and 1.0 cm for women. The annual change in the BMI of men who skipped breakfast four to six times per week was 0.061 kg m-2 higher, and that of those who skipped breakfast seven times per week was 0.046 kg m-2 higher, compared with those who did not skip breakfast. Annual changes in the WC of male participants who skipped breakfast seven times per week was 0.248 cm higher than that of those who did not skip breakfast. Skipping breakfast was not associated with changes in BMI or WC in women. CONCLUSIONS: Skipping breakfast was closely associated with annual changes in BMI and WC among men, and eating breakfast more than four times per week may prevent the excessive body weight gain associated with skipping breakfast.

19.
Occup Environ Med ; 63(8): 545-50, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16601012

RESUMO

OBJECTIVES: To clarify the causes of death of residents with renal tubular dysfunction induced by cadmium (Cd) in the environment. METHODS: A 15 year follow up study was performed with the inhabitants living in the Cd polluted Kakehashi River basin in Japan. Standardised mortality ratios (SMRs) for causes of death, classified by ICD-9, were computed using the person-years method to investigate the excess mortality of subjects with urinary beta2-MG (microglobulin) > or =1000 microg/gCr. Mortality risk analysis was performed using Cox's proportional model to compare mortality between subjects with urinary beta2-MG > or =1000 and <1000 microg/gCr, and to investigate the relationship between the degree of urinary beta2-MG and mortality. RESULTS: Excess mortality due to heart failure and cerebral infarction in both sexes, and nephritis and nephrosis in men, was observed among subjects with urinary beta2-MG > or =1000 microg/gCr. Significant increases in mortality risk for cerebral infarction in men and for malignant neoplasms in women with urinary beta2-MG > or =1000 microg/gCr were observed during the first five year observation period. For nephritis and nephrosis, the mortality risks for men and women with urinary beta2-MG > or =1000 microg/gCr significantly increased over the 15 year observation period. The mortality risks for heart failure and cerebral infarction increased in proportion to the increased urinary beta2-MG in both sexes. Increased mortality risks for nephritis and nephrosis were identified in the subjects with urinary beta2-MG > or =10000 microg/gCr in both sexes. CONCLUSION: Renal tubular dysfunction induced by Cd affected the causes of death, and mortality for heart failure, cerebral infarction, and nephritis and nephrosis was increased among inhabitants living in a Cd polluted area in Japan. In women, cancer mortality may have been increased while Cd pollution was ongoing.


Assuntos
Cádmio/toxicidade , Nefropatias/mortalidade , Túbulos Renais/efeitos dos fármacos , Idoso , Causas de Morte , Exposição Ambiental/efeitos adversos , Feminino , Seguimentos , Humanos , Nefropatias/induzido quimicamente , Nefropatias/fisiopatologia , Túbulos Renais/fisiopatologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Microglobulina beta-2/urina
20.
Biochim Biophys Acta ; 666(3): 370-81, 1981 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-7326249

RESUMO

We have studied the cholesterol-binding reaction with purified steroid-free cytochrome P-450scc. By mixing an aqueous solution of cholesterol-, pregnenolone- and progesterone-free cytochrome with cholesterol-containing liposomes, the low to high spin conversion of the hemoprotein was observed spectrophotometrically and by electron spin resonance spectroscopy. When the binding rates were compared at a fixed molar heme: cholesterol ratio of 1 : 1, 20 mol% cholesterol-dioleoylglycerophosphocholine liposomes react with the cytochrome at a faster rate than 50 mol% cholesterol-dimyristoylglycerophosphocholine liposomes, indicating that the availability of cholesterol molecules in an unsaturated membrane is better than in a saturated membrane. When the number of cholesterol-dioleoylglycerophosphocholine liposomes was increased, the cholesterol-binding rates increased markedly. These results imply that the collision of the liposomes with the soluble hemoprotein molecules plays an important role in the binding reaction under our experimental conditions. The binding reaction was found to be temperature-dependent with a refractive temperature at near 20 degrees C. From the comparison of the binding abilities among cholesterol derivatives tested, wer conclude that the alpha-face of the A-B transfused rings and the portion of the hydrocarbon side-chain of cholesterol are important for the binding. Additionally, polar derivatives had faster rates than non-polar steroids in structurally homologous series.


Assuntos
Colesterol/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Hidroxicolesteróis/metabolismo , Lipossomos , Córtex Suprarrenal/metabolismo , Adrenodoxina/metabolismo , Animais , Bovinos , Sistema Enzimático do Citocromo P-450/isolamento & purificação , Ferredoxina-NADP Redutase/metabolismo , Cinética , Mitocôndrias/metabolismo , Ligação Proteica , Solubilidade , Espectrofotometria
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