Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 62
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
Small ; 18(9): e2105881, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34921582

RESUMO

The formation of hydrides challenges the integrity of zirconium (Zr) fuel cladding in nuclear reactors. The dynamics of hydride precipitation are complex. Especially, the formation of the butterfly or bird-nest configurations of dislocation structures around hydride is rather intriguing. By in-situ transmission electron microscopy experiments and density functional theory simulations, it is discovered that hydride growth is a hybrid displacive-diffusive process, which is regulated by intermittent dislocation emissions. A strong tensile stress field around the hydride tip increases the solubility of hydrogen in Zr matrix, which prevents hydride growth. Punching-out dislocations reduces the tensile stress surrounding the hydride, decreases hydrogen solubility, reboots the hydride precipitation and accelerates the growth of the hydride. The emission of dislocations mediates hydride growth, and finally, the consecutively emitted dislocations evolve into a butterfly or bird-nest configuration around the hydride.


Assuntos
Hidrogênio , Zircônio , Hidrogênio/química , Microscopia Eletrônica de Transmissão , Zircônio/química
2.
Hepatol Res ; 49(6): 676-686, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30680865

RESUMO

AIM: Transient elastography (TE) is the gold standard for measurement of liver stiffness. The usefulness of shear wave elastographies (SWE) is well accepted. However, the measurement values cannot be equivalently compared because cut-off values for the diagnosis of liver fibrosis are different among those devices. We aimed to clarify correlations, to generate the regression equations between TE and SWEs, and to compare the diagnostic ability of each device to diagnose liver fibrosis. METHODS: A total of 109 patients with chronic liver disease who underwent liver biopsy and same-day evaluation of liver stiffness using six ultrasound devices were analyzed. The diagnostic ability of liver stiffness from each ultrasound device and correlations between TE and each SWE were analyzed. RESULTS: Liver stiffness measured by all six ultrasound devices increased significantly as liver fibrosis stage advanced (P < 0.001). Receiver operating characteristic (ROC) curve analysis for predicting significant fibrosis (≥F2) and cirrhosis yielded area under the ROC curve (AUROC) values based on TE of 0.830 (95% confidence interval [CI], 0.755-0.905) and 0.959 (95% CI, 0.924-0.995), respectively. The AUROCs for predicting significant fibrosis (≥F2) and cirrhosis (F4) based on SWE from all five ultrasound devices were over 0.8 and 0.9, respectively. Furthermore, the correlation coefficients between TE values and SWE values from five ultrasound devices were all over 0.8, indicating a strong relationship. CONCLUSION: Our study showed strong correlations between TE and SWEs with high correlation coefficients. The regression equations between TE and SWEs demonstrated the ability to compare the measurement values in each device equivalently.

3.
Hepatol Res ; 47(2): 204-215, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26990490

RESUMO

AIM: To examine the relationship between serum Wisteria floribunda agglutinin-positive Mac-2-binding protein (WFA+ -M2BP) levels and liver histological findings for patients with treatment naïve chronic hepatitis B (CHB). METHODS: A total of 189 treatment naïve-CHB patients were analyzed. We examined the effect of pretreatment serum WFA+ -M2BP levels on histological findings compared with other laboratory markers, including aspartate aminotransferase (AST) to platelet ratio index, Fibrosis-4 index, platelet count, AST to alanine aminotransferase (ALT) ratio, and hyaluronic acid as liver fibrosis markers, and AST value, ALT value, and serum interferon-γ-inducible protein-10 level as liver inflammation markers. RESULTS: The WFA+ -M2BP value ranged from 0.3 cut-off index (COI) to 12.9 COI (median value, 1.2 COI). The degree of liver fibrosis was significantly stratified according to WFA+ -M2BP level in each group except for groups F2 and F3 and the degree of liver inflammation activity was significantly stratified according to WFA+ -M2BP level in each group. For predicting F4, WFA+ -M2BP level yielded the highest area under the receiver operating characteristic curve (AUROC) with a level of 0.87 and for predicting advanced liver fibrosis (≥F3) and significant liver fibrosis (≥F2), WFA+ -M2BP level yielded the second highest AUROCs (both, 0.77) among six fibrotic markers. For predicting severe (A3) or significant liver inflammation activity (≥A2), AUROCs of WFA+ -M2BP level were 0.78 and 0.76. CONCLUSION: The WFA+ -M2BP level can be a useful marker for assessing liver histological findings in patients with treatment-naïve CHB, although it has several limitations.

4.
Hepatol Res ; 47(12): 1223-1234, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28019060

RESUMO

AIM: To develop and validate a simple predictive model using easily obtained clinical parameters to predict decreased skeletal muscle mass (DSMM) in chronic liver disease (CLD) patients (n = 652). METHODS: Study subjects were divided into a training set (n = 326) and a validation set (n = 326). Decreased skeletal muscle mass was diagnosed based on skeletal muscle mass index measured by bioimpedance analysis. Variables significantly associated with DSMM were identified using univariate and multivariate analyses in the training set and used to construct a predictive formula. Receiver operating characteristic (ROC) curve analysis was carried out and the predictive model was validated in the validation set. Subgroup analyses were undertaken based on gender, age, or cirrhosis status of patients. RESULTS: Body mass index (BMI), age, serum albumin, and branched-chain amino acid to tyrosine ratio (BTR) were determined to be significant predictive factors for DSMM. A composite formula "BALB score" was constructed [-7.740 + (0.539 × BMI) + (-0.112 × age) + (1.358 × albumin) + (-0.264 × BTR)]. The BALB score had the best predictive characteristics among all variables in both population sets (area under the ROC curve, 0.877-0.898). Patients with DSMM were stratified into three BALB score categories (>4, 0-4, and <0). Subgroup analyses also showed that BALB scoring was predictive of DSMM irrespective of gender, age, or cirrhosis status. The BALB score significantly correlated with psoas muscle index on computed tomography (rs = 0.6083 for men; rs = 0.6814 for women). CONCLUSION: The BALB scoring system based on routinely used clinical parameters offers a convenient and non-invasive method for predicting DSMM in compensated CLD patients with high accuracy.

5.
Hepatol Res ; 47(10): 1042-1052, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27862791

RESUMO

AIMS: To investigate the impact of low skeletal muscle mass (LSMM) on survival as compared with protein-energy malnutrition (PEM) in patients with liver cirrhosis (LC). METHODS: A total of 206 individuals with LC were analyzed. We retrospectively examined the impact of LSMM, as defined by psoas muscle mass at the third lumber on computed tomography, on survival as compared with PEM. In terms of comparison of the effects of LSMM and PEM on survival, we used time-dependent receiver operating characteristics (ROC) analysis. RESULTS: Our study cohort included 115 men and 91 women with a median age of 67 years. There were 140 patients with Child-Pugh A, 62 with Child-Pugh B, and 4 with Child-Pugh C. A total of 117 patients (56.8%) had LSMM and 52 patients (25.2%) had PEM. The proportion of PEM in patients with LSMM (31.62%, 37/117) was significantly higher than in patients without LSMM (16.85%, 15/89) (P = 0.0229). In the multivariate analysis for the entire cohort, the presence of hepatocellular carcinoma, lower body mass index, presence of LSMM, lower triglyceride value, poorer renal function, and higher des-γ-carboxy prothrombin value were found to be significant adverse predictors linked to overall survival, while presence of PEM tended to be significant. In the time-dependent ROC analysis, all area under the ROCs for survival in LSMM at each time point were higher than those in PEM except for Child-Pugh B patients. CONCLUSION: In this comparison of LSMM and PEM on clinical outcomes in LC patients, it was shown that LSMM may have stronger prognostic impact than PEM.

6.
Hepatol Res ; 47(3): E74-E84, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27075409

RESUMO

AIM: We aimed to construct a predictive model for advanced fibrosis containing Wisteria floribunda agglutinin-positive Mac-2-binding protein (WFA+ -M2BP) level in patients with chronic hepatitis C (CHC) and to validate its accuracy in an independent cohort. METHODS: A total of 386 patients with CHC were retrospectively analyzed. For the purpose of this study, we formed a training set (n = 210) and a validation set (n = 176). In the training set, we investigated variables linked to the presence of advanced fibrosis using univariate and multivariate analyses. We constructed a formula for predicting advanced fibrosis and validated its accuracy in the validation cohort. Receiver operating characteristic curve (ROC) analysis was carried out for calculating the area under the ROC (AUROC). RESULTS: In multivariate analyses, WFA+ -M2BP (P = 0.029) and prothrombin time (PT) (P = 0.018) were found to be significant predictive factors linked to the presence of advanced fibrosis; platelet count (P = 0.098) and hyaluronic acid (P = 0.078) showed borderline statistical significance for the presence of advanced fibrosis. Using these four variables (with the initials MPPH), we constructed the following formula: MPPH score = -3.584 - (0.275 × WFA+ -M2BP) + (0.068 × platelet count) + (0.042 × PT) - (0.005 × hyaluronic acid). In the training and validation sets, MPPH score yielded the highest AUROCs (0.87 and 0.83) for predicting advanced fibrosis among eight serum liver fibrosis markers. Similarly, in the training and validation sets, MPPH score had the highest diagnostic accuracies for predicting advanced fibrosis among eight serum variables (81.4% and 74.4%). CONCLUSION: Our proposed MPPH scoring system can be useful for predicting advanced fibrosis in patients with CHC.

7.
Hepatol Res ; 46(6): 575-83, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26418076

RESUMO

AIM: We aimed to examine the relationship between serum Wisteria floribunda agglutinin positive Mac-2-binding protein (WFA(+) -M2BP) levels and serum interferon-γ-inducible protein-10 (IP-10) levels and liver histological findings for patients with primary biliary cirrhosis (PBC) compared with other laboratory fibrotic or inflammatory parameters. METHODS: A total of 57 PBC patients were analyzed. Receiver-operator curve (ROC) analysis was performed for calculating the area under the ROC (AUROC) for WFA(+) -M2BP, IP-10 and four serum fibrosis markers for the presence of liver cirrhosis (F4) or advanced fibrosis (F3 or F4). Similarly, ROC analysis of WFA(+) -M2BP, IP-10, aspartate aminotransferase and alanine aminotransferase for the presence of severe inflammation activity (A3) was performed. RESULTS: There were eight men and 49 women (median age, 59 years). As for histological findings, F4 was observed in five patients, F3 in 11, F2 in 17, F1 in 24 and F0 in zero, whereas A3 was observed in seven patients, A2 in 27, A1 in 19 and A0 in four. The WFA(+) -M2BP levels ranged from 0.5 cut-off index (COI) to 13.6 COI (median, 1.8), while serum IP-10 levels ranged 121.9-1835.9 pg/mL (median, 571.5). For predicting liver cirrhosis, WFA(+) -M2BP yielded the highest AUROC (0.97, P < 0.01). For predicting severe liver inflammation activity (A3), WFA(+) -M2BP and serum IP-10 yielded the highest AUROC with a level of 0.87. WFA(+) -M2BP levels significantly correlated with serum IP-10 levels (rs = 0.55, P < 0.0001). CONCLUSION: Serum WFA(+) -M2BP and serum IP-10 can be useful markers for predicting histological findings in PBC patients.

8.
Hepatol Res ; 46(12): 1194-1202, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26836229

RESUMO

AIM: To examine the relationship between the Wisteria floribunda agglutinin positive Mac-2-binding protein (WFA+ -M2BP) level and histological findings for patients with non-alcoholic steatohepatitis (NASH). METHODS: A total of 134 NASH patients (mean age, 51.7 years) were analyzed. We examined the effect of WFA+ -M2BP level on severity of liver fibrosis comparing with other laboratory markers, including aspartate aminotransferase (AST) to alanine aminotransferase (ALT) ratio, AST to platelet ratio index (APRI), FIB-4 index, platelet count and hyaluronic acid as serum liver fibrosis markers. Receiver-operator curve (ROC) analysis was performed for calculating the area under the ROC (AUROC). RESULTS: The WFA+ -M2B P-value ranged from 0.2 cut-off index (COI) to 9.6 COI (median, 0.9). The median values in each fibrosis stage were: 0.7 COI in F1, 0.7 COI in F2, 1.2 COI in F3 and 2.4 COI in F4 (P < 0.001). For predicting liver cirrhosis (F4), WFA+ -M2BP level had the AUROC of 0.854 (sensitivity, 69.2%; specificity, 88.4%) and for predicting advanced liver fibrosis (≥F3), WFA+ -M2BP level yielded the second highest AUROC with a level of 0.842 (sensitivity, 73.7%; specificity, 80.2%) and for predicting significant liver fibrosis (≥F2), WFA+ -M2BP level yielded the highest AUROC with a level of 0.663 (sensitivity, 47.2%; specificity, 78.6%) among six liver fibrosis markers. The median values in patients with ballooning scores 1 (n = 58) and 2 (n = 76) were 0.6 and 1.1 COI, respectively (P < 0.001). CONCLUSION: Serum WFA+ -M2BP level can be useful for assessing liver histological findings in patients with NASH.

9.
Hepatol Res ; 46(13): 1358-1366, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26950182

RESUMO

This study aimed to compare the severity of sleep problems between chronic hepatitis C (CHC) patients treated with interferon (IFN)-based triple therapy (pegylated [Peg]-IFN plus ribavirin [RBV] plus simeprevir [SMV]) and those who received IFN-free direct-acting antiviral (DAA) therapy. METHODS: Our study included 31 patients in group A (Peg-IFN/RBV/SMV combination therapy) and 41 patients in the group B (IFN-free DAA therapy). We prospectively compared the effect of each antiviral treatment regimen on sleep conditions between the two groups adding actigraphy data. Five parameters detected by actigraphy (objective assessment) and scores of the Pittsburgh Sleep Quality Index (subjective assessment, n = 30 [group A] and 35 [group B]) were estimated. The causal effect of each therapy on sleep disturbances was evaluated at baseline and at 4 weeks after commencement of therapy. RESULTS: In terms of baseline characteristics, no significant differences between groups were found, except for hepatitis C virus genotype. In group A, sustained virological response 12 rate was 83.9% (26/31), whereas in group B it was 95.1% (39/41). In group A, each score of waking after sleep onset, activity index, wake episodes, and Pittsburgh Sleep Quality Index at 4 weeks significantly increased compared to those evaluated at baseline. In group B, scores of all variables except for sleep episodes at 4 weeks did not significantly change compared to those at baseline. CONCLUSION: Interferon-based triple therapy in patients with CHC may cause significant sleep disturbances. Interferon-free DAA therapy is less likely to deteriorate sleep conditions in patients with CHC.

10.
Int J Mol Sci ; 17(9)2016 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-27626413

RESUMO

We aimed to examine the effect of Wisteria floribunda agglutinin-positive Mac-2-binding protein (WFA⁺-M2BP) level on survival comparing with other laboratory liver fibrosis markers in hepatitis C virus (HCV)-related compensated liver cirrhosis (LC) (n = 165). For assessing prognostic performance of continuous fibrosis markers, we adapted time-dependent receiver operating characteristics (ROC) curves for clinical outcome. In time-dependent ROC analysis, annual area under the ROCs (AUROCs) were plotted. We also calculated the total sum of AUROCs in all time-points (TAAT score) in each fibrosis marker. WFA⁺-M2BP value ranged from 0.66 cutoff index (COI) to 19.95 COI (median value, 5.29 COI). Using ROC analysis for survival, the optimal cutoff point for WFA⁺-M2BP was 6.15 COI (AUROC = 0.79348, sensitivity = 80.0%, specificity = 74.78%). The cumulative five-year survival rate in patients with WFA⁺-M2BP ≥ 6.15 COI (n = 69) was 43.99%, while that in patients with WFA⁺-M2BP < 6.15 COI (n = 96) was 88.40% (p < 0.0001). In the multivariate analysis, absence of hepatocellular carcinoma (p = 0.0008), WFA⁺-M2BP < 6.15 COI (p = 0.0132), achievement of sustained virological response (p < 0.0001) and des-γ-carboxy prothrombin < 41 mAU/mL (p = 0.0018) were significant favorable predictors linked to survival. In time-dependent ROC analysis in all cases, WFA⁺-M2BP had the highest TAAT score among liver fibrosis markers. In conclusion, WFA⁺-M2BP can be a useful predictor in HCV-related compensated LC.


Assuntos
Antígenos de Neoplasias/sangue , Hepatite C/metabolismo , Hepatite C/patologia , Cirrose Hepática/patologia , Cirrose Hepática/virologia , Glicoproteínas de Membrana/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Antivirais/uso terapêutico , Biomarcadores/sangue , Feminino , Hepatite C/tratamento farmacológico , Humanos , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/metabolismo , Masculino , Pessoa de Meia-Idade , Lectinas de Plantas , Prognóstico , Curva ROC , Receptores de N-Acetilglucosamina , Análise de Sobrevida , Adulto Jovem
11.
Biochem Biophys Res Commun ; 454(3): 453-8, 2014 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-25450683

RESUMO

Although the development of anti-interferon (IFN)-α neutralizing antibodies (NAbs) is likely to be a common clinical problem for patients with various diseases treated with IFN, anti-IFN-α NAb has been exceptionally considered to have no clinical significance in the treatment of chronic hepatitis C with pegylated IFN-α (Peg-IFN-α). However, we recently clarified that the presence of NAb was associated with a non-response to the Peg-IFN plus ribavirin (RBV) therapy. In this study, we used the HCV-replicon system with genotype 1b, and investigated the role of anti-IFN-α NAb in the response to telaprevir (TVR)-containing new antiviral therapy for hepatitis C virus (HCV). Anti-IFN-α NAb-positive sera specifically inhibited the anti-HCV effects of IFN-α, without any effect on the activity of IFN-ß in vitro. The NAb-positive sera also inhibited the IFN-α-dependent induction of interferon-stimulated genes, MxA and OAS-1, in a dose-dependent manner. Although TVR monotherapy decreased the HCV-RNA in vitro, the HCV-RNA was increased again with the development of TVR-resistant mutations. When IFN-α was administrated with TVR, the replication of HCV was continuously suppressed for more than a month. However, in the presence of anti-IFN-α NAb-positive sera, even when IFN-α was combined with TVR, the levels of HCV-RNA exhibited a time-course similar to that with TVR monotherapy, and HCV with TVR-resistant mutations emerged. In conclusion, our findings suggest that the presence of IFN-α NAb decreases the antiviral effects of IFN-α and may be related to the development of TVR-resistant mutated viruses.


Assuntos
Anticorpos Neutralizantes/imunologia , Antivirais/farmacologia , Farmacorresistência Viral , Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/farmacologia , Oligopeptídeos/farmacologia , Antivirais/imunologia , Antivirais/uso terapêutico , Quimioterapia Combinada , Hepacivirus/genética , Hepacivirus/imunologia , Hepacivirus/fisiologia , Hepatite C Crônica/sangue , Hepatite C Crônica/imunologia , Humanos , Interferon-alfa/imunologia , Interferon-alfa/uso terapêutico , Mutação/efeitos dos fármacos , Oligopeptídeos/uso terapêutico , Proteínas não Estruturais Virais/genética , Replicação Viral/efeitos dos fármacos
12.
Ann Hepatol ; 12(3): 471-8, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23619265

RESUMO

BACKGROUND: The relationships between the metabolic parameters and the endoscopic findings of esophageal varices have been poorly investigated. We investigated the association of the branched-chain amino acids to tyrosine ratio (BTR) with the severity of liver fibrosis and esophageal varices. MATERIAL AND METHODS: We studied hepatitis C virus (HCV)-positive chronic liver disease patients who had undergone liver biopsy (n = 149). The relationship between the BTR values and the liver fibrotic stage was investigated. We also studied whether the BTR value was associated with the presence and bleeding risk of varices in patients with HCV-related compensated cirrhosis. RESULTS: The mean values of the BTR decreased with the progression of the fibrosis (METAVIR score: F0-1: 6.40 ± 1.19; F2: 5.85 ± 1.33; F3: 5.24 ± 0.97, F4: 4.78 ± 1.14). In the 58 patients with HCV-related compensated cirrhosis, the mean values of the BTR decreased with the severity of varices (patients without varices: 5.01 ± 1.15, patients with a low-risk varices: 4.42 ± 1.06, patients with a high-risk varices: 3.86 ± 1.02). The BTR value was significantly lower in the patients with varices than in those without varices (4.17 ± 1.07 vs. 5.01 ± 1.15, P < 0.01). The BTR value was also significantly lower in the patients with a high risk of hemorrhage than in those with a low risk (3.86 ± 1.02 vs. 4.78 ± 1.14, P < 0.01). Furthermore, the BTR value was the most significantly different parameter, with the smallest P-value among all the factors examined, including the platelet count and albumin level. CONCLUSION: A decreased BTR value was found to be associated with the progression of liver fibrosis and severity of varices.


Assuntos
Aminoácidos de Cadeia Ramificada/sangue , Varizes Esofágicas e Gástricas/sangue , Cirrose Hepática/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Biomarcadores/sangue , Biópsia , Progressão da Doença , Varizes Esofágicas e Gástricas/diagnóstico , Varizes Esofágicas e Gástricas/virologia , Feminino , Hemorragia Gastrointestinal/virologia , Hepatite C/complicações , Humanos , Cirrose Hepática/diagnóstico , Cirrose Hepática/virologia , Masculino , Pessoa de Meia-Idade , Medição de Risco , Fatores de Risco , Índice de Gravidade de Doença , Tirosina/sangue , Adulto Jovem
13.
Hepatogastroenterology ; 60(121): 149-52, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-22975583

RESUMO

BACKGROUND/AIMS: The development of esophageal varices depends on the progression of liver fibrosis. However, it has not yet been sufficiently clarified whether biomarkers of liver fibrosis can be used to predict the incidence of varices in cirrhotic patients with a well-maintained liver function (Child-Pugh class A). METHODOLOGY: Three established markers of liver fibrosis, including AST-to-ALT ratios (AAR), FIB-4 and AST-to-platelet ratio indices (APRI), were analyzed in HCV-positive cirrhotic patients with Child-Pugh class A status, and the relationships between these markers and the risk of variceal bleeding were investigated. RESULTS: The values of AAR and FIB-4 in the patient with varices with a high risk of hemorrhage were significantly higher than those in the patients without high-risk varices, whereas the value of APRI was not found to be related to the risk of variceal bleeding. Of all the parameters examined, the values of AAR were the most significantly different between the two (with or without high-risk varices) groups. In addition, the values of AAR increased in line with variceal severity. CONCLUSIONS: The value of AAR is related to the severity and risk of variceal bleeding in patients with HCV-related compensated cirrhosis.


Assuntos
Alanina Transaminase/sangue , Aspartato Aminotransferases/sangue , Varizes Esofágicas e Gástricas/fisiopatologia , Hepatite C/complicações , Cirrose Hepática/fisiopatologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores , Varizes Esofágicas e Gástricas/sangue , Feminino , Hemoglobinas Glicadas/análise , Humanos , Cirrose Hepática/sangue , Cirrose Hepática/etiologia , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença
14.
Sci Rep ; 11(1): 4503, 2021 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-33627765

RESUMO

Solid-state precipitation is a key heat-treatment strategy for strengthening engineering alloys. Therefore, predicting the precipitation process of localized solute-rich clusters, such as Guinier-Preston (GP) zones, is necessary. We quantitatively evaluated the critical nucleus size and nucleation barrier of GP zones in Al-Cu alloys, illustrating the precipitation preferences of single-layer (GP1) and double-layer (GP2) GP zones. Based on classical nucleation theory using an effective multi-body potential for dilute Al-Cu systems, our model predicted GP1 and GP2 precipitation sequences at various temperatures and Cu concentrations in a manner consistent with experimental observations. The crossover between formation enthalpy curves of GP1 and GP2 with increasing cluster size determines the critical conditions under which GP2 zones can nucleate without prior formation of GP1 zones. This relationship reflects competing interactions within and between clusters. The results illustrate the underlying mechanisms of competing nucleation between zones, and provide guidance for tailoring aging conditions to achieve desired mechanical properties for specific applications.

15.
Phys Rev E ; 104(2-2): 025310, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34525587

RESUMO

The application of existing semigrand canonical ensemble Monte Carlo algorithms to alloys requires the chemical potential difference values between pairs of atomic species in the alloys as inputs. However, finding the appropriate values for a target system at a desired temperature and bulk composition is a time-consuming task consisting of multiple test runs to determine the chemical potential differences. This problem becomes more serious when dealing with systems containing three or more atomic species, such as medium- and high-entropy alloys, due to the increase of the number of chemical potential differences that need to be calculated. Here we propose a method for sampling from the semigrand canonical ensemble that relies on energy databases acting as an external atomic reservoir at the desired temperature and composition. Given these energy databases, the desired bulk composition and corresponding chemical potential differences can be satisfied in a "single" Monte Carlo simulation. Moreover, the energy databases shed light on the underlying energetics of alloys, reflecting their local chemical ordering. We demonstrate the validity of this method using analyses of segregation isotherms at grain boundaries and dislocations in two alloy systems: Fe-1-at.-%-Si and NiCoCr medium-entropy alloy. We also discuss the possibly relevant information contained in such energy databases.

16.
Gan To Kagaku Ryoho ; 37(5): 919-22, 2010 May.
Artigo em Japonês | MEDLINE | ID: mdl-20495329

RESUMO

We report a case of hepatocellular carcinoma (HCC) in association with autoimmune hepatitis (AIH). In May 2003, a 66- year-old man was admitted to our hospital because of acute liver dysfunction. He was diagnosed with AIH, and his liver function was normalized by oral administration of the corticosteroid. In July 2007, when he was admitted for the treatment of bacterial pneumonia, two liver tumors (S4: ø4 cm and S2: ø1 cm) were revealed by abdominal CT scan, and the serum level of AFP was high. According to the findings of imaging diagnosis and laboratory data, the patient was diagnosed as having HCC. Since the standard invasive therapies of HCC were not accepted by the patient and his family, he was treated by oral administration of UFT-E (tegafur/uracil: 200 mg/day). Three months after the initiation of administration, CT scan showed a remarkable reduction of the tumors, and his serum AFP level was decreased to the normal range. This case shows that HCC develops in an AIH patient even if liver function is maintained in the normal range. It also suggests the clinical usefulness of UFT-E in the management of HCC given the difficulty of treatment by the standard therapies.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Hepatite Autoimune/complicações , Neoplasias Hepáticas/tratamento farmacológico , Administração Oral , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Biomarcadores Tumorais/sangue , Biópsia , Carcinoma Hepatocelular/complicações , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/patologia , Humanos , Neoplasias Hepáticas/complicações , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/patologia , Masculino , Radiografia , Tegafur/administração & dosagem , Tegafur/uso terapêutico , Uracila/administração & dosagem , Uracila/uso terapêutico , alfa-Fetoproteínas/análise
17.
Mech Ageing Dev ; 129(9): 550-7, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18597819

RESUMO

Previous studies of telomeres and telomerase have focused mostly on mammals, and data for other vertebrates are limited. We analyzed both telomere length (terminal restriction fragment length) and telomerase activity in a small freshwater teleost fish, the medaka (Oryzias latipes), and found that the telomeres shorten during ageing despite the fact that a considerable amount of telomerase activity is ubiquitously detectable throughout the life of the fish. Since the telomere attrition rate during development was greater than that in adulthood, telomere length is inversely correlated with the increase in body length. The difference in telomere length among medaka individuals was similar to that in humans, and the individual specific differences were evident even at the earliest embryonic stage. Telomerase activity was ubiquitously detectable not only in the body of the embryo but also in the systemic organs of mature individuals throughout their entire life span. These data suggest that telomere attrition during ageing in medaka, which is similar to that in humans, may be a major factor determining their mortality, and that telomere maintenance through strong telomerase activity may be required for the characteristic lifelong continuous growth of this fish.


Assuntos
Envelhecimento/genética , Oryzias/genética , Oryzias/metabolismo , Telomerase/metabolismo , Telômero/genética , Envelhecimento/metabolismo , Animais , Ativação Enzimática/fisiologia , Feminino , Longevidade/genética , Masculino , Oryzias/crescimento & desenvolvimento , Telomerase/fisiologia , Telômero/metabolismo
18.
Ann Clin Lab Sci ; 48(6): 801-804, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30610054

RESUMO

Obesity is regarded as a risk factor for various benign and malignant diseases. We evaluated whether or not the body mass index (BMI) was associated with the presence of gastroesophageal varices in asymptomatic hepatitis C virus (HCV)-related compensated cirrhosis (Child-Pugh grade A status). Among a total of 794 patients of HCV-related chronic liver disease, 90 had histologically-proven cirrhosis, and 63 were classified as having compensated cirrhosis (30 had varices, and the remaining 33 did not). The values of prothrombin time (%) and platelet count were significantly lower in the patients with varices than in those without (P=0.042 and P=0.013, respectively). In addition to the abovementioned variables, the BMI was significantly higher in the patients with varices than in those without (P=0.031). In a multivariate analysis, only an increased BMI (odds ratio 1.205, 95% confidence interval 1.009-1.486, P=0.039) was independently associated with the presence of varices. In asymptomatic HCV-related compensated cirrhosis with a Child-Pugh A status, an increased BMI is suggested to be related to the presence of gastroesophageal varices.


Assuntos
Índice de Massa Corporal , Varizes Esofágicas e Gástricas/complicações , Varizes Esofágicas e Gástricas/patologia , Hepacivirus/patogenicidade , Hepatite C Crônica/complicações , Hepatite C Crônica/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Varizes Esofágicas e Gástricas/virologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada
19.
BMJ Open Gastroenterol ; 5(1): e000193, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29527314

RESUMO

INTRODUCTION: In most chronic pancreatitis (CP) cases, malabsorption, pain, and weight loss are the leading clinical symptoms, which significantly worsen the quality of life (QOL) and decreased QOL in patients with CP can cause sleep disorder. There is a growing body of evidence that recognises the favourable effects of physical exercise (PE), however, there are limited data currently available concerning patients with CP undergoing PE. Actigram is a device for gathering objective sleep/awake data in the natural sleeping surroundings over an extended time period. In this study, we will aim to prospectively investigate the effect of PE on sleep disorder as assessed by actigram in patients with CP. METHODS AND ANALYSIS: This study is a non-double-blind randomised controlled trial. Study participants will be randomised into the PE group and the control group. When registering patients, precise assessment for nutritional status and daily physical activities will be undertaken in each study patient. In the PE group, physical activities equal to or higher than walking for 60 min/day should be strongly recommended. Sleep quality using actigram will be prospectively compared in the two groups. The primary endpoint is the activity index in actigram at 12 weeks. ETHICS AND DISSEMINATION: Ethical approval for the study was granted by the Institutional Review Board at Hyogo College of Medicine (approval number 2767). Results will be presented at relevant conferences and submitted to an appropriate journal following trial closure and analysis. TRIAL REGISTRATION NUMBER: UMIN000029265 (https://upload.umin.ac.jp/); Pre-results.

20.
BMJ Open Gastroenterol ; 5(1): e000194, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29527315

RESUMO

INTRODUCTION AND PURPOSE: Sarcopenia is defined as a decrease in muscle mass and muscle strength, and it has been demonstrated to be an adverse predictor in numerous types of cancers. Exercise therapy (ET) carries multiple health benefits in several diseases. Despite these clinical benefits, there are limited data available regarding patients with pancreatic cancer (PC) undergoing ET. We aim to prospectively examine the effect of ET on sarcopenia in patients with PC. METHODS AND ANALYSIS: All clinical stages of PC can be included. When registering study subjects, a precise evaluation of the nutritional status and the daily physical activities performed will be undertaken individually, for each participant. Study participants will be randomly allocated into two groups: (1) the ET and standard therapy group and (2) the standard therapy group. Amelioration of sarcopenia at 3 months postrandomisation will be the primary endpoint. Muscle mass will be calculated using bioimpedance analysis. Sarcopenia will be defined based on the current Asian guidelines. Participants will be instructed to perform exercises with > 3 metabolic equivalents (mets; energy consumption in physical activities/resting metabolic rate) for 60 min/day and to perform exercises with > 23 mets/week. In the ET group, physical activities equal to or greater than walking for 60 min/day will be strongly recommended. ETHICS AND DISSEMINATION: The Institutional Review Board at Hyogo College of Medicine has approved this study protocol (approval no. 2772). The final data will be publicly announced. A report releasing the study results will be submitted for publication. TRIAL REGISTRATION NUMBER: UMIN000029271; Pre-results.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA