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Neodymium (Nd) based perovskite (Nd1-xCoxFeO3) nanostructures were processed to address the rising energy and environment crisis through offering solutions by photocatalytic and photoelectrochemical (PEC) water splitting reactions. The impact of cobalt (Co) ions on the physicochemical properties of Nd-perovskites were studied using X-ray diffraction (XRD), Raman and electron microscopic instruments. The interaction of metal ions was studied in depth via X-ray photoelectron spectroscopy (XPS). Absorption and photoluminescence signals inferred the optical band gap to be lowered and defect states to increase upon Co substitution. Improved photocatalytic efficacy in Nd1-xCoxFeO3 was evaluated by comparative studies using NdFeO3. Secondly, the enhanced conductivities in Nd1-xCoxFeO3 studied via Nyquist plot was found to be advantageous in photoelectrode fabrication for PEC functions. Time-dependent photocurrent density results affirmed the stability in processed devices. Co ions were also inferred to boost the separation of charge carriers effectively. The improved performance in Nd1-xCoxFeO3 nanostructures were well justified to the successful incorporation of Co ions that sway the Nd-O, Co-O and Co-Fe-O bondings and boost the photon absorption and electronic conductivity to facilitate the observed performance.
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Nanoestruturas , Água , Compostos de Cálcio , Catálise , Neodímio , Óxidos , TitânioRESUMO
AIM: To evaluate the correlation between the apparent diffusion coefficient (ADC) and various histopathological parameters in small hepatocellular carcinomas (HCCs). MATERIALS AND METHODS: In 143 surgically resected small HCCs, the mean and minimum ADC values, tumour-to-liver ADC ratio, and normalised ADC (ADC of the HCC/ADC of the spleen) were correlated to the tumour grade, microvascular invasion (MVI), cellularity, fatty change, degree of fibrosis, and lymphocytic infiltration using linear regression analysis, the Wilcoxon rank sum test, or Spearman's rank correlation. RESULTS: No significant correlation was found between the ADC parameters and tumour grade. In the univariate analysis, the ADC ratio of the tumour was significantly correlated with MVI as well as the degree of fibrosis and lymphocyte infiltration of the HCC (p=0.017, 0.042, and 0.002, respectively). The ADC of the tumour was significantly correlated with the degree of lymphocyte infiltration of the HCC (p=0.049). In the multivariate analysis, the ADC ratio of the tumour was an independent parameter for MVI and the degree of lymphocyte infiltration of the HCC (p=0.034 and <0.001, respectively), and the ADC of the tumour was an independent parameter for the degree of lymphocyte infiltration of the HCC (p=0.009). There was no significant correlation between the other ADCs and pathological tumour parameters. CONCLUSION: The tumour grade of small HCCs was not correlated with ADC parameters. The tumour-to-liver ADC ratio was a significant independent parameter for the degree of lymphocyte infiltration and MVI of small HCCs.
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Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Microvasos/patologia , Neoplasias Vasculares/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Imagem de Difusão por Ressonância Magnética/métodos , Feminino , Humanos , Cirrose Hepática/patologia , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Invasividade Neoplásica , Estudos RetrospectivosRESUMO
AIM: To integrate various criteria for borderline resectable pancreatic cancer (BRPC) based on radiological parameters using classification tree analysis. MATERIALS AND METHODS: The institutional review board approved this retrospective study and waived the requirement for informed consent. Two hundred and thirty-five tumour-vein interfaces and 67 tumour-artery interfaces in 245 patients with surgically confirmed pancreatic ductal adenocarcinoma who underwent both preoperative computed tomography (CT) and magnetic resonance imaging (MRI) were assessed by two independent readers. Radiological parameters for evaluation of the tumour-vascular interface were boundary, length of interface, degree of circumferential interface, and contour deformity of affected vessels. Classification tree analysis was performed to determine parameters associated with vascular invasion using pathological and surgical results as the reference standard. RESULTS: In the classification tree analysis for the tumour-vein interface, contour deformity and degree of circumferential interface were the first and second determining factors, respectively, for both surgical and pathological vascular invasion. For the tumour-artery interface, boundary and degree of circumferential interface were the first and second determining factors for surgical invasion, while contour deformity and length of interface were the first and second determining factors for pathological invasion. The BRPC group of modified criteria arbitrarily formed based on the results had similar surgical (74.1-81.6%) and pathological (54.3-63.3%) venous invasion compared to that of the National Comprehensive Cancer Network (NCCN) criteria, and the lowest surgical (33.3%) and pathological (6.7%) arterial invasion compared with those in previously established criteria for BRPC (43.3-55.6% and 22.2-26.1%, respectively). CONCLUSION: Various criteria for BRPCs were integrated using classification tree analysis, and a modified criterion for BRPC, which provides satisfactory results, was established.
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Carcinoma Ductal Pancreático/diagnóstico por imagem , Árvores de Decisões , Neovascularização Patológica/diagnóstico por imagem , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Vasculares/diagnóstico por imagem , Idoso , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/cirurgia , Meios de Contraste , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Invasividade Neoplásica , Neovascularização Patológica/patologia , Neovascularização Patológica/cirurgia , Pancreatectomia/métodos , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/cirurgia , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Neoplasias Vasculares/patologia , Neoplasias Vasculares/cirurgiaRESUMO
AIM: To compare the long-term therapeutic outcomes of repeated radiofrequency ablation (RFA) with that of transarterial chemoembolisation (TACE) in patients with local tumour progression (LTP) after initial RFA treatment for hepatocellular carcinoma (HCC). MATERIALS AND METHODS: This retrospective study was approved by the institutional review board and the requirement for informed consent was waived. Between July 2006 and February 2012, 713 patients underwent RFA for single HCC as a first-line treatment. Fifty-eight patients who showed LTP as initial tumour recurrence post-RFA treatment were included. Patients were treated with either repeated RFA (n=33) or TACE (n=25). TACE was performed as an alternative therapeutic option when repeated RFA was not feasible based on the planning ultrasonography. Recurrence-free and overall survival rates were estimated using the Kaplan-Meier method. Prognostic factors for outcomes were evaluated using the Cox proportional hazards model. RESULTS: Both groups did not show significant differences in terms of baseline characteristics, with the exception being the proportion of subphrenic tumours (p=0.031). The RFA and TACE groups did not differ significantly in their 5-year recurrence-free and overall survival rates (17% versus 10.7% and 72.7% versus 51.9%, respectively, with all p-values >0.05). In addition, multivariate analyses revealed that type of treatment was not associated with recurrence-free or overall survival in patients with post-RFA LTP. CONCLUSION: TACE is an effective treatment, comparable to repeated RFA, in patients with LTP after initial RFA when repeated RFA is not feasible.
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Carcinoma Hepatocelular/terapia , Ablação por Cateter/métodos , Quimioembolização Terapêutica/métodos , Neoplasias Hepáticas/terapia , Idoso , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/cirurgia , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Fígado/diagnóstico por imagem , Fígado/cirurgia , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/cirurgia , Masculino , Pessoa de Meia-Idade , Retratamento , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Resultado do Tratamento , UltrassonografiaRESUMO
AIM: To assess the long-term therapeutic outcomes of radiofrequency ablation (RFA) versus surgical resection (SR) as a first-line treatment for patients meeting the Milan criteria with multiple hepatocellular carcinomas (HCCs). MATERIALS AND METHODS: This retrospective study was approved by the institutional review board and the requirement for informed consent was waived. Between January 2004 and December 2009, among 3,441 patients with treatment-naive HCCs, 88 patients meeting the Milan criteria with multiple HCCs (Barcelona Clinic Liver Cancer [BCLC] A stage) who underwent either RFA (n=62) or SR (n=26) were included. Recurrence-free survival (RFS) and overall survival (OS) rates were compared by using propensity score matching. In addition, multivariate analysis was performed for assess the prognostic factor. RESULTS: Matching yielded 20 matched pairs of patients. In the two matched groups, the RFS rates were 30% and 30% at 5- and 10-years, respectively, in the RFA group and 60% and 48.6% in the SR group (p=0.054). The corresponding OS rates were 63.3% and 46.1% in the RFA group and 100% and 73.6% in the SR group, respectively (p=0.061). In multivariate analysis, treatment type was independently associated with RFS (hazard ratio [HR]=0.51; p=0.043) whereas it was not a statistically significant factor for OS (HR=0.50; p=0.088). CONCLUSION: In patients meeting the Milan criteria with multiple HCCs (BCLC A stage), SR may provide better RFS compared to RFA.
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Carcinoma Hepatocelular/cirurgia , Neoplasias Hepáticas/cirurgia , Ablação por Radiofrequência/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Hepatectomia , Humanos , Fígado/cirurgia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do TratamentoRESUMO
AIM: To determine the preoperative computed tomography (CT) parameters that predict portal vein/superior mesenteric vein (PV-SMV) invasion in patients with pancreatic head cancer, and to assess whether PV-SMV invasion affects patient survival. MATERIALS AND METHODS: Sixty patients with PV-SMV invasion, and 60 randomly selected patients without it, who had undergone preoperative CT and subsequent surgery for pancreatic head cancer were enrolled. The following CT parameters were evaluated using multivariate logistic regression and receiver operating characteristic analyses to predict vessel invasion (tumour size and margin, length of involved vessel, distance from the tumour to the vessel, vessel irregularity, the teardrop sign, and tumour-vein interface [TVI]). The Cox proportional hazard model was used to evaluate the effects of PV-SMV invasion on survival. RESULTS: In multivariate analysis, tumour size (odds ratio [OR]=1.99) and TVI (OR=3.79 [≤90°], 20.66 [>90°, ≤180°], and 47.24 [>180°]) were independent CT predictors of PV-SMV invasion (p<0.05); they achieved a sensitivity of 87%, a specificity of 75%, and an accuracy of 81%; however, PV-SMV invasion did not affect patient survival after surgery (p=0.374). CONCLUSION: In patients with pancreatic head cancer, preoperative CT parameters can predict PV-SMV invasion with high accuracy. PV-SMV invasion did not affect treatment outcome after surgery.
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Veias Mesentéricas/patologia , Neoplasias Pancreáticas/patologia , Veia Porta/patologia , Neoplasias Vasculares/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Veias Mesentéricas/diagnóstico por imagem , Pessoa de Meia-Idade , Invasividade Neoplásica , Tratamentos com Preservação do Órgão/métodos , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Pancreáticas/cirurgia , Pancreaticoduodenectomia/métodos , Veia Porta/diagnóstico por imagem , Cuidados Pré-Operatórios/métodos , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Carga Tumoral , Neoplasias Vasculares/diagnóstico por imagem , Neoplasias PancreáticasRESUMO
AIM: To assess the significant factors on rectal magnetic resonance imaging (MRI) to predict the likelihood of a diagnosis of metastasis for indeterminate hepatic lesions found at computed tomography (CT) in patients with rectal cancer. MATERIALS AND METHODS: A total of 207 patients with rectal cancer who underwent preoperative contrast-enhanced abdominopelvic CT, and rectal and liver MRI were included. Univariate analysis and multivariate logistic regression were used to evaluate the determining factors for the significance of indeterminate hepatic lesions on CT in patients with rectal cancer. RESULTS: Hepatic metastases were diagnosed in 29 (20.9%) of 139 patients who had indeterminate hepatic lesions on preoperative CT obtained for rectal cancer. On univariate analysis, carcinoembryonic antigen level, N stage, mesorectal fascia (MRF) invasion, diameter of superior haemorrhoidal vein, and mesorectal vascular lesion (MVL) grade on rectal MRI (p<0.05) were associated with the possibility of metastasis for indeterminate hepatic lesions on CT. On multivariate analysis, MVL grade and MRF invasion on rectal MRI were independent factors associated with the possibility of metastasis for indeterminate hepatic lesions on CT (p<0.0005 and p=0.0066, respectively). CONCLUSION: MVL grade and MRF invasion on rectal MRI are independent factors for estimating hepatic metastasis among indeterminate hepatic lesions on CT in patients with rectal cancer.
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Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/secundário , Neoplasias Retais/diagnóstico por imagem , Neoplasias Retais/patologia , Tomografia Computadorizada por Raios X , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Retrospectivos , Medição de Risco , Fatores de RiscoRESUMO
AIM: To evaluate the efficacy of radiofrequency ablation (RFA) and transarterial chemoembolisation (TACE) as a first-line treatment for isolated intrahepatic recurrent hepatocellular carcinoma (IIR-HCC) after liver transplantation (LT). MATERIALS AND METHODS: This retrospective study was approved by the institutional review board. Between January 2005 and January 2015, 588 consecutive patients underwent LT for the treatment of HCC. Among them, 27 patients with IIR-HCCs after LT who were treated with RFA (n=6) or TACE (n=21) as a first-line treatment were retrospectively included in this study. Disease-free and overall survival rates were estimated using the Kaplan-Meier method. Risk factors affecting these outcomes were assessed with Cox regression models. RESULTS: Except for the total number of recurrent tumours and time-to-tumour recurrence after LT, baseline characteristics were not significantly different between the groups. The 2-year disease-free survival rates for RFA and TACE (20% versus 14%, respectively; p=0.180) and 4-year overall survival rates (33% versus 25%, respectively; p=0.065) were not significantly different between groups. In addition, the types of treatment were not associated with disease-free or overall survival in multivariate analyses. CONCLUSION: TACE may be an effective treatment comparable to RFA in patients with IIR-HCC after LT when RFA is not feasible.
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Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/terapia , Ablação por Cateter/mortalidade , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/terapia , Transplante de Fígado/mortalidade , Recidiva Local de Neoplasia/mortalidade , Adulto , Ablação por Cateter/estatística & dados numéricos , Quimioembolização Terapêutica/mortalidade , Quimioembolização Terapêutica/estatística & dados numéricos , Terapia Combinada/mortalidade , Terapia Combinada/estatística & dados numéricos , Comorbidade , Feminino , Humanos , Transplante de Fígado/estatística & dados numéricos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/prevenção & controle , Prevalência , República da Coreia/epidemiologia , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do TratamentoRESUMO
AIM: To evaluate the conventional and diffusion-weighted magnetic resonance imaging (MRI) images of tumefactive gallbladder sludge. MATERIALS AND METHODS: The institutional review board approved this retrospective study. Between January 2006 and January 2015, 3478 patients were diagnosed with gallbladder sludge by ultrasonography (US). Of them, 12 patients (eight male, four female; mean age, 63.6 years) with 12 tumefactive gallbladder sludge lesions, who underwent subsequent MRI for further evaluation within 1 month, were included in this study. Data regarding the clinical features, presence of enhancement, and signal intensities of the T2-, T1-, and diffusion-weighted images were collected. RESULTS: All cases of tumefactive sludge were detected incidentally. None of the patients had any predisposing factors for biliary sludge. The tumefactive gallbladder sludge was predominantly seen as a well-defined mass-like lesion. It showed hyperintensity on T1-weighted images (91.7%, 11/12), and variable signal intensities on T2-weighted images. Most of the tumefactive sludge lesions showed no enhancement on the dynamic phases (90%, 9/10). There were no cases with diffusion restriction. Among the patients with follow-up US data (n=7), all the lesions were found to have either disappeared or decreased in size. CONCLUSION: Although tumefactive gallbladder sludge on US can mimic gallbladder cancer, its hyperintensity on a T1-weighted image, and the absence of enhancement and diffusion restriction on MRI images can be helpful for differentiating it from a tumorous condition.
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Bile , Vesícula Biliar/anatomia & histologia , Imageamento por Ressonância Magnética , Idoso , Meios de Contraste , Imagem de Difusão por Ressonância Magnética , Feminino , Gadolínio DTPA , Humanos , Aumento da Imagem , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos RetrospectivosRESUMO
The decoration of a BC3 monolayer with the polylithiated molecules CLi4 and OLi2 has been extensively investigated to study the hydrogen-storage efficiency of the materials by first principles electronic structure calculations. The binding energies of both lithiated species with the BC3 substrate are much higher than their respective cohesive energies, which confirms the stability of the doped systems. A significant positive charge on the Li atom in each of the dopants facilitates the adsorption of multiple H2 molecules under the influence of electrostatic and van der Waals interactions. We observe a high H2 -storage capacity of 11.88 and 8.70 wt % for the BC3 -CLi4 and BC3 -OLi2 systems, respectively, making them promising candidates as efficient energy-storage systems.
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AIM: To evaluate the usefulness of fusion imaging with real-time ultrasonography (US) and three-dimensional (3D) US for the guidance of radiofrequency ablation (RFA) of hepatocellular carcinomas (HCCs) 2-5 cm in diameter. MATERIALS AND METHODS: This study was conducted as a retrospective cohort study. It was approved by the institutional review board and informed consent was waived. During percutaneous RFA of HCCs, targeting was performed under conventional fusion imaging guidance, whereas monitoring and controlling were conducted under fusion with 3D US guidance. Technical success, technique effectiveness, incidence of major complications, and local tumour progression rate were evaluated. According to tumour size (small: <3 cm versus medium: 3-5 cm), the roundness indexes of the ablation zones and local tumour progression rates were compared. RESULTS: There were 29 small-sized HCCs (2.5 ± 0.3 cm) and 17 medium-sized HCCs (3.4 ± 0.5 cm). All RFA procedures were performed in a single RFA session. Both the technical success and technique effectiveness rates were 100%. One patient with medium-sized HCC developed a hepatic abscess (n = 1) as a major complication. The local tumour progression rate was 8.7% (4/46) with a mean follow-up period of 18.2 months. The roundness indexes of the ablation zone were not significantly different between small- and medium-sized HCCs, and the local tumour progression rates were also not significantly different between the two groups [3.4% (1/29) versus 17.6% (3/17); p = 0.135]. CONCLUSION: Image fusion with real-time US and 3D US is useful for the guidance of percutaneous RFA for HCCs 2-5 cm in diameter.
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Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/cirurgia , Ablação por Cateter/métodos , Imageamento Tridimensional , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/patologia , Feminino , Humanos , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , UltrassonografiaRESUMO
AIM: To assess gadoxetic acid-enhanced and diffusion-weighted (DW) magnetic resonance imaging (MRI) findings of inflammatory myofibroblastic tumours (IMTs) of the liver using combined 2-[(18)F]-fluoro-2-deoxy-D-glucose (FDG) positron-emission tomography (PET)/computed tomography (CT), and to evaluate clinical course with volume change on follow-up. MATERIALS AND METHODS: Gadoxetic acid-enhanced and DW MRI findings of 18 histopathologically proven hepatic IMTs in 13 patients were retrospectively reviewed. The clinical features, qualitative (signal intensity and enhancement pattern) and quantitative data [apparent diffusion coefficient (ADC)], and analysis of FDG-PET/CT findings were collected. The volume of IMTs during follow-up was measured using a tumour half-time. RESULTS: Most of the IMTs (9/13, 69.2%) were found incidentally. IMTs were predominantly seen as well-defined (16/18, 88.9%) masses with peritumoural hypointensity during the hepatobiliary phase (17/18, 94.4%) and showed five morphological types: target-like hypervascular mass (n = 9), hypovascular mass (n = 5), heterogeneous enhancing mass (n = 2), sclerosing mass (n = 1), and non-target hypervascular mass (n = 1). All lesions showed diffusion restriction and hypermetabolic mass on FDG-PET/CT images. The mean ADC value and ADC ratio of IMTs to liver were 0.828 × 10(-3) mm(2)/s and 0.76, respectively. On follow-up, all 11 IMTs showed rapid regression (mean tumour half-time, 38.49 days) with no tumour recurrence or distant metastasis. CONCLUSION: Although hepatic IMTs can mimic abscess and malignant tumours at MRI and PET/CT, peritumoural hypointensity during the hepatobiliary phase with rapid regression on follow-up could be helpful for differentiating it from other lesions.
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Meios de Contraste , Imagem de Difusão por Ressonância Magnética , Fluordesoxiglucose F18 , Gadolínio DTPA , Neoplasias Hepáticas/diagnóstico , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos , Adulto , Idoso , Diagnóstico Diferencial , Feminino , Seguimentos , Humanos , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Tomografia por Emissão de Pósitrons/métodos , Estudos Retrospectivos , Sensibilidade e EspecificidadeRESUMO
AIM: To evaluate the technical feasibility of artificial ascites formation using an angiosheath before percutaneous radiofrequency ablation (RFA) for hepatic tumours and to determine predictive factors affecting the technical failure of artificial ascites formation. MATERIALS AND METHODS: This retrospective study was approved by the institutional review board. One hundred and thirteen patients underwent percutaneous RFA of hepatic tumours after trying to make artificial ascites using an angiosheath to avoid collateral thermal damage. The technical success rate of making artificial ascites using an angiosheath and conversion rate to other techniques after initial failure of making artificial ascites were evaluated. The technical success rate for RFA was assessed. In addition, potential factors associated with technical failure including previous history of transcatheter arterial chemoembolization (TACE) or RFA, type of abdominal surgery, and adjacent perihepatic structures were reviewed. Predictive factors for the technical failure of artificial ascites formation were analysed using multivariate analysis. RESULTS: The technical success rates of artificial ascites formation by angiosheath and that of RFA were 84.1% (95/113) and 97.3% (110/113), respectively. The conversion rate to other techniques after the failure of artificial ascites formation using an angiosheath was 15.9% (18/113). Previous hepatic resection was the sole independent predictive factor affecting the technical failure of artificial ascites formation (p<0.001, odds ratio = 29.03, 95% confidence interval: 4.56-184.69). CONCLUSION: Making artificial ascites for RFA of hepatic tumours using an angiosheath was technically feasible in most cases. However, history of hepatic resection was a significant predictive factor affecting the technical failure of artificial ascites formation.
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Ablação por Cateter/métodos , Drenagem/métodos , Neoplasias Hepáticas/terapia , Fígado/cirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Ascite/induzido quimicamente , Estudos de Coortes , Drenagem/instrumentação , Falha de Equipamento , Estudos de Viabilidade , Feminino , Humanos , Fígado/diagnóstico por imagem , Neoplasias Hepáticas/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Agulhas , Punções/métodos , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos , Falha de Tratamento , Resultado do Tratamento , Ultrassonografia , Água/administração & dosagem , Adulto JovemRESUMO
AIM: To compare the long-term local control of hepatocellular carcinoma (HCC) and risk of peritoneal seeding via percutaneous radiofrequency ablation (RFA) using artificial ascites with those of RFA without artificial ascites. MATERIALS AND METHODS: The Institutional Review Board approved this retrospective study. From April 2005 to February 2008, 160 patients (121 men, 39 women; age range 36-79 years) with a single subcapsular HCC (mean size 2.19 cm) were treated with ultrasonography-guided percutaneous RFA as a first-line therapy. Forty-four patients were treated with RFA using artificial ascites, whereas the other 116 patients were treated without artificial ascites. The cumulative local tumour progression (LTP) and peritoneal seeding were compared in both groups using follow-up computed tomography (CT). Cumulative LTP rates were analysed using the Kaplan-Meier method and the log-rank test. Risk of peritoneal seeding was investigated by means of multivariate analysis. RESULTS: The overall median follow-up period was 52.5 months (range 13-76 months). The 1, 2, 4, and 6 year cumulative LTP rates were 17.1, 27.6, 35.2, and 35.2%, respectively, in the group with artificial ascites, and 8, 15.2, 26.6, and 34.4% in the group without artificial ascites, without significant difference (p = 0.332). The rates of peritoneal seeding were 6.8% (3/44) in the group with artificial ascites and 2.6% (3/116) in the group without artificial ascites, a non-significant difference (p = 0.347). The biopsy prior to RFA was the independent risk factor of peritoneal seeding regardless of the use of artificial ascites. CONCLUSION: Long-term local tumour control and risk of peritoneal seeding were comparable for RFA with or without artificial ascites when used as a first-line therapy for subcapsular HCC.
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Carcinoma Hepatocelular/cirurgia , Ablação por Cateter , Neoplasias Hepáticas/cirurgia , Adulto , Idoso , Ascite/cirurgia , Carcinoma Hepatocelular/diagnóstico por imagem , Ablação por Cateter/efeitos adversos , Ablação por Cateter/métodos , Feminino , Seguimentos , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Inoculação de Neoplasia , Radioterapia Conformacional/métodos , Estudos Retrospectivos , Resultado do Tratamento , Ultrassonografia de Intervenção/métodosRESUMO
AIM: To evaluate the benefit of diffusion-weighted imaging (DWI) in differentiating xanthogranulomatous cholecystitis from the wall-thickening type of gallbladder cancer. MATERIALS AND METHODS: This retrospective study was approved by the institutional review board. Fourteen patients with xanthogranulomatous cholecystitis and 19 patients with the wall-thickening type of gallbladder cancer were included. Qualitative (visual diffusion restriction compared to liver parenchyma) and quantitative [apparent diffusion coefficient (ADC)] analyses were performed. Conventional MRI findings including dynamic enhancement pattern between the two groups were also analysed. Two observers independently reviewed conventional magnetic resonance imaging (MRI) images and subsequently reviewed combined conventional MRI and DWI images. Pairwise comparison of the receiver operating characteristic (ROC) curves was used to compare diagnostic performances. RESULTS: In conventional MRI findings, xanthogranulomatous cholecystitis showed significant continuity of enhancing mucosal line [79% (11/14) versus 26% (5/19), p = 0.003] and intramural T2-high signal intensity [64% (9/14) versus 21% (4/19), p = 0.012] compared to the wall-thickening type of gallbladder cancer. The enhancement pattern of gallbladder cancer compared to liver parenchyma showed earlier onset than that of xanthogranulomatous cholecystitis (p = 0.001). Diffusion restriction was more frequently seen in the wall-thickening type of gallbladder cancer (68%, 13/19) than in xanthogranulomatous cholecystitis (7%, 1/14; p < 0.001). The mean ADC value of xanthogranulomatous cholecystitis was higher than that of the wall-thickening type of gallbladder cancer with statistical significance (1.637 × 10(-3) mm(2)/s versus 1.076 × 10(-3) mm(2)/s, p = 0.005). Diagnostic performance [area under ROC curve (Az)] of both observers improved significantly after additional review of DWI; Az improved from 0.737 to 0.930 (p = 0.027) for observer 1 and from 0.675 to 0.938 (p = 0.008) for observer 2. CONCLUSION: Addition of DWI to conventional MRI improves discrimination between xanthogranulomatous cholecystitis and the wall-thickening type of gallbladder cancer.
Assuntos
Colecistite/diagnóstico , Imagem de Difusão por Ressonância Magnética/métodos , Neoplasias da Vesícula Biliar/diagnóstico , Granuloma/diagnóstico , Xantomatose/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Colecistite/patologia , Meios de Contraste , Diagnóstico Diferencial , Feminino , Gadolínio DTPA , Neoplasias da Vesícula Biliar/patologia , Granuloma/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Estudos Retrospectivos , Estatísticas não Paramétricas , Xantomatose/patologiaRESUMO
Microbial fuel cells (CS-UFC) utilize waste resources containing biodegradable materials that play an essential role in green energy. MFC technology generates "carbon-neutral" bioelectricity and involves a multidisciplinary approach to microbiology. MFCs will play an important role in the harvesting of "green electricity." In this study, a single-chamber urea fuel cell is fabricated that uses these different wastewaters as fuel to generate power. Soil has been used to generate electrical power in microbial fuel cells and exhibited several potential applications to optimize the device; the urea fuel concentration is varied from 0.1 to 0.5 g/mL in a single-chamber compost soil urea fuel cell (CS-UFC). The proposed CS-UFC has a high power density and is suitable for cleaning chemical waste, such as urea, as it generates power by consuming urea-rich waste as fuel. The CS-UFC generates 12 times higher power than conventional fuel cells and exhibits size-dependent behavior. The power generation increases with a shift from the coin cell toward the bulk size. The power density of the CS-UFC is 55.26 mW/m2. This result confirmed that urea fuel significantly affects the power generation of single-chamber CS-UFC. This study aimed to reveal the effect of soil properties on the generated electric power from soil processes using waste, such as urea, urine, and industrial-rich wastewater as fuel. The proposed system is suitable for cleaning chemical waste; moreover, the proposed CS-UFC is a novel, sustainable, cheap, and eco-friendly design system for soil-based bulk-type design for large-scale urea fuel cell applications.
RESUMO
Magnesium ferrites (MgFe2O4) are important class of ferrites that have been receiving greater attention as promising excellent photocatalyst due to its low cost, wide light spectrum response and environment-friendly nature. However, its poor electronic conductivity and fast charge carrier recombination hinders its electrocatalytical applications. Hence, accelerating charge carriers separation efficiency is important to modify the photoelectrochemical performance of MgFe2O4. Herein, novel Zn ions doped MgFe2O4 nanospheres are fabricated for the first time. Zn ions are doped into MgFe2O4 nanostructures from surface to enhance their charge separation efficiency. The doped MgFe2O4 nanostructures show significant photocatalytic activity and enhanced photocurrent density than that of pristine MgFe2O4.The improved photoelectrocatalytic performance is attributed to doping effect, were Zn ions actually enhance the conductivity. Zn ions enhance the activity of MgFe2O4 and accelerate the charge transfer properties in MgFe2O4. The results highlight that Zn doped MgFe2O4 nanospheres could be a potential candidate for photocatalytic and photoelectrochemical applications.
Assuntos
Nanoestruturas , Água , Catálise , Luz , ZincoRESUMO
BACKGROUND AND PURPOSE: Risk-stratification models based on patient and disease characteristics are useful for aiding clinical decisions and for comparing the quality of care between different physicians or hospitals. In addition, prediction of mortality is beneficial for optimizing resource utilization. We evaluated the accuracy and discriminating power of the random forest (RF) to predict 30-day mortality of spontaneous intracerebral hemorrhage (SICH). METHODS: We retrospectively studied 423 patients admitted to the Taichung Veterans General Hospital who were diagnosed with spontaneous SICH within 24 h of stroke onset. The initial evaluation data of the patients were used to train the RF model. Areas under the receiver operating characteristic curves (AUC) were used to quantify the predictive performance. The performance of the RF model was compared to that of an artificial neural network (ANN), support vector machine (SVM), logistic regression model, and the ICH score. RESULTS: The RF had an overall accuracy of 78.5% for predicting the mortality of patients with SICH. The sensitivity was 79.0%, and the specificity was 78.4%. The AUCs were as follows: RF, 0.87 (0.84-0.90); ANN, 0.81 (0.77-0.85); SVM, 0.79 (0.75-0.83); logistic regression, 0.78 (0.74-0.82); and ICH score, 0.72 (0.68-0.76). The discriminatory power of RF was superior to that of the other prediction models. CONCLUSIONS: The RF provided the best predictive performance amongst all of the tested models. We believe that the RF is a suitable tool for clinicians to use in predicting the 30-day mortality of patients after SICH.
Assuntos
Inteligência Artificial , Hemorragia Cerebral/diagnóstico , Hemorragia Cerebral/mortalidade , Sistemas de Apoio a Decisões Clínicas/tendências , Idoso , Algoritmos , Hemorragia Cerebral/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mortalidade/tendências , Valor Preditivo dos Testes , Prognóstico , Estudos Retrospectivos , Medição de Risco/métodos , Sensibilidade e EspecificidadeRESUMO
Scanning electron microscopy (SEM) images and transmission electron microscopy (TEM) images showed that the one-dimensional GaN nanorods were formed on Al2O3 (0001) substrates by using hydride vapor phase epitaxy without a catalyst. Selected area electron diffraction (SAED) pattern and high-resolution TEM (HRTEM) results showed that GaN nanorods grown on Al2O3 (0001) substrates had crystalline wurzite structures and (0001) preferential orientation. The morphologies of GaN nanorods were affected by the flow rates of the source materials. The orientational relationships between the GaN nanorods and the Al2O3 substrates were (0001)GaN perpendicular (0001) Al2O3 and [0110]GaN perpendicular [1120] Al2O3. Cross-sectional and plan-view atomic arrangements of the fully relaxed interfacial region are described on the basis of the TEM, the SAED pattern, and the HRTEM results.
RESUMO
The acute problem of eutrophication increasing in the environment is due to the increase of industrial wastewater, synthetic nitrogen, urine, and urea. This pollutes groundwater, soil and creates a danger to aquatic life. Therefore, it is advantageous to use these waste materials in the form of urea as fuel to generate power using Microbial Fuel Cell (MFC). In this work, we studied the compost soil MFC(CSMFC) unlike typical MFC with urea from the compost as fuel and graphite as a functional electrode. The electrochemical techniques such as Cyclic Voltammetry, Chronoamperometry are used to characterise CSMFC. It is observed that the CSMFC in which the compost consists of urea concertation of 0.5 g/ml produces maximum power. Moreover, IV measurement is carried out using polarization curves in order to study its sustainability and scalability. Bacterial studies were also playing a significant role in power generation. The sustainability study revealed that urea is consumed in CSMFC to generate power. This study confirmed that urea has a profound effect on the power generation from the CSMFC. Our focus is to get power from the soil processes in future by using waste like urine, industrial wastewater, which contains much amount of urea.