Pancreatic cancer(PC)remains one of the deadliest cancers worldwide,and has a poor,five-year survival rate of 5%.Although complete surgical resection is the only curative therapy for pancreatic cancer,less than20%of n...Pancreatic cancer(PC)remains one of the deadliest cancers worldwide,and has a poor,five-year survival rate of 5%.Although complete surgical resection is the only curative therapy for pancreatic cancer,less than20%of newly-diagnosed patients undergo surgical resection with a curative intent.Due to the lack of early symptoms and the tendency of pancreatic adenocarcinoma to invade adjacent structures or to metastasize at an early stage,many patients with pancreatic cancer already have advanced disease at the time of their diagnosis and,therefore,there is a high mortality rate.To improve the patient survival rate,early detection of PC is critical.The diagnosis of PC relies on computed tomography(CT)and/or magnetic resonance imaging(MRI)with magnetic resonance cholangiopancreatography(MRCP),or biopsy or fine-needle aspiration using endoscopic ultrasound(EUS).Although multi-detector row computed tomography currently has a major role in the evaluation of PC,MRI with MRCP facilitates better detection of tumors at an early stage by allowing a comprehensive analysis of the morphological changes of the pancreas parenchyma and pancreatic duct.The diagnosis could be improved using positron emission tomography techniques in special conditions in which CT and EUS are not completely diagnostic.It is essential for clinicians to understand the advantages and disadvantages of the various pancreatic imaging modalities in order to be able to make optimal treatment and management decisions.Our study investigates the current role and innovative techniques of pancreatic imaging focused on the detection of pancreatic cancer.展开更多
The aim of this study was to illustrate the role of noninvasive imaging tools such as ultrasonography,multidetector row computed tomography,and magnetic resonance imaging in the evaluation of pediatric and adult liver...The aim of this study was to illustrate the role of noninvasive imaging tools such as ultrasonography,multidetector row computed tomography,and magnetic resonance imaging in the evaluation of pediatric and adult liver recipients and potential liver donors,and in the detection of potential complications arising from liver transplantation.展开更多
AIM: To assess the diagnostic accuracy of multidetectorrow computed tomography(MDCT) as compared with conventional magnetic resonance imaging(MRI), in identifying mesorectal fascia(MRF) invasion in rectal cancer patie...AIM: To assess the diagnostic accuracy of multidetectorrow computed tomography(MDCT) as compared with conventional magnetic resonance imaging(MRI), in identifying mesorectal fascia(MRF) invasion in rectal cancer patients.METHODS: Ninety-one patients with biopsy proven rectal adenocarcinoma referred for thoracic and abdominal CT staging were enrolled in this study. The contrast-enhanced MDCT scans were performed on a 256 row scanner(ICT, Philips) with the following acquisition parameters: tube voltage 120 KV, tube current 150-300 m As. Imaging data were reviewed as axial and as multiplanar reconstructions(MPRs) images along the rectal tumor axis. MRI study, performed on 1.5 T with dedicated phased array multicoil, included multiplanar T2 and axial T1 sequences and diffusion weighted images(DWI). Axial and MPR CT images independently were compared to MRI and MRF involvement was determined. Diagnostic accuracy of both modalities was compared and statistically analyzed.RESULTS: According to MRI, the MRF was involved in 51 patients and not involved in 40 patients. DWI allowed to recognize the tumor as a focal mass with high signal intensity on high b-value images, compared with the signal of the normal adjacent rectal wall or with the lower tissue signal intensity background. The number of patients correctly staged by the native axial CT images was 71 out of 91(41 with involved MRF; 30 with not involved MRF), while by using the MPR 80 patients were correctly staged(45 with involved MRF; 35 with not involved MRF). Local tumor staging suggested by MDCT agreed with those of MRI, obtaining for CT axial images sensitivity and specificity of 80.4% and 75%, positive predictive value(PPV) 80.4%, negative predictive value(NPV) 75% and accuracy 78%; while performing MPR the sensitivity and specificity increased to 88% and 87.5%, PPV was 90%, NPV 85.36% and accuracy 88%. MPR images showed higher diagnostic accuracy, in terms of MRF involvement, than native axial images, as compared to the reference magnetic resonance images. The展开更多
Myocardial pathologies are major causes of morbidity and mortality worldwide. Early detection of loss of cellular integrity and expansion in extracellular volume(ECV) in myocardium is critical to initiate effective tr...Myocardial pathologies are major causes of morbidity and mortality worldwide. Early detection of loss of cellular integrity and expansion in extracellular volume(ECV) in myocardium is critical to initiate effective treatment. The three compartments in healthy myocardium are: intravascular(approximately 10% of tissue volume), interstitium(approximately 15%) and intracellular(approximately 75%). Myocardial cells, fibroblasts and vascular endothelial/smooth muscle cells represent intracellular compartment and the main proteins in the interstitium are types Ⅰ/Ⅲ collagens. Microscopic studies have shown that expansion of ECV is an important feature of diffuse physiologic fibrosis(e.g., aging and obesity) and pathologic fibrosis [heart failure, aortic valve disease, hypertrophic cardiomyopathy, myocarditis, dilated cardiomyopathy, amyloidosis, congenital heart disease, aortic stenosis, restrictive cardiomyopathy(hypereosinophilic and idiopathic types), arrythmogenic right ventricular dysplasia and hypertension]. This review addresses recent advances in measuring of ECV in ischemic and non-ischemic myocardial pathologies. Magnetic resonance imaging(MRI) has the ability to characterize tissue proton relaxation times(T1, T2, and T2*). Proton relaxation times reflect the physical and chemical environments of water protons in myocardium. Delayed contrast enhanced-MRI(DE-MRI) and multi-detector computed tomography(DE-MDCT) demonstrated hyper-enhanced infarct, hypo-enhanced microvascular obstruction zone and moderately enhanced peri-infarct zone, but are limited for visualizing diffuse fibrosis and patchy microinfarct despite the increase in ECV. ECV can be measured on equilibrium contrast enhanced MRI/MDCT and MRI longitudinal relaxation time mapping. Equilibrium contrast enhanced MRI/MDCT and MRI T1 mapping is currently used, but at a lower scale, as an alternative to invasive sub-endomyocardial biopsies to eliminate the need for anesthesia, coronary catheterization and possibility of tissue sampling error. Similar to d展开更多
The metal organic framework functionalized with sulfonic acid was combined with magnetic nanoparticles to fabricate a new nanocomposite(denoted as Fe3O4@PDA@Zr-SO3H).By combining with gas chromatography-electron captu...The metal organic framework functionalized with sulfonic acid was combined with magnetic nanoparticles to fabricate a new nanocomposite(denoted as Fe3O4@PDA@Zr-SO3H).By combining with gas chromatography-electron capture detector,the resulting Fe3O4@PDA@Zr-SO3H nanocomposite was successfully used as a high-efficiency adsorbent for pre-concentrating eight organochlorine pesticides from water sample in environment.Apart from the ability of fast separation,the as-prepared Fe3O4@PDA@Zr-SO3H nanocomposite also exhibited high adsorption capacity for organochlorine pesticides.With the use of optimal experimental conditions,the linear relationship can be obtained in the range of 0.05~300μg/L,the correlation coefficient was over 0.9978,and the relative standard deviation was located in 2.5%-7.7%.Moreover,the limit of detection and quantification was between0.005-0.016μg/L and 0.017~0.050μg/L.Finally,the nanocomposite was used for the determination of organochlorine pesticides from environmental water samples,and displayed the recovery of 82%-118%.展开更多
Radiation is considered one of the possible causes of cancer disease with natural background sources including cosmic, terrestrial and internal radiation. A number of cancer disease cases have been reported in Kargi w...Radiation is considered one of the possible causes of cancer disease with natural background sources including cosmic, terrestrial and internal radiation. A number of cancer disease cases have been reported in Kargi with their causes not properly documented. The present work characterized the radioactivity in soil and water, to find out possible causes of radiation in KARGI-KENYA by studying magnetic intensities, anomalous zones with depth to magnetic sources and delineating subsurface structures. A total of 117 soil and 14 water samples were collected from the entire area and analysed for radionuclides due to <sup>40</sup>K, <sup>232</sup>Th and <sup>226</sup>Ra. Measurement methods of proton magnetometer and gamma spectrometry employing a high purity germanium (HPGe) detector were employed basically to evaluate the magnetic survey and radiological hazard of radioactivities respectively. A total of 51 magnetic field measurements were taken on the eastern part of Kargi, a place suspected to have more concentration of radionuclides. The results showed that there could have been a fractionation during weathering period or metasomatic activity of the radioelements involvement. This study also reveals that the mining activities in the nearby study area could have affected the geologic formation causing more fracturing in rocks and pronounced subsurface structures as a result of mining that could have served as passage for leachates from pollutants as well as the level of radiation in the study area.展开更多
文摘Pancreatic cancer(PC)remains one of the deadliest cancers worldwide,and has a poor,five-year survival rate of 5%.Although complete surgical resection is the only curative therapy for pancreatic cancer,less than20%of newly-diagnosed patients undergo surgical resection with a curative intent.Due to the lack of early symptoms and the tendency of pancreatic adenocarcinoma to invade adjacent structures or to metastasize at an early stage,many patients with pancreatic cancer already have advanced disease at the time of their diagnosis and,therefore,there is a high mortality rate.To improve the patient survival rate,early detection of PC is critical.The diagnosis of PC relies on computed tomography(CT)and/or magnetic resonance imaging(MRI)with magnetic resonance cholangiopancreatography(MRCP),or biopsy or fine-needle aspiration using endoscopic ultrasound(EUS).Although multi-detector row computed tomography currently has a major role in the evaluation of PC,MRI with MRCP facilitates better detection of tumors at an early stage by allowing a comprehensive analysis of the morphological changes of the pancreas parenchyma and pancreatic duct.The diagnosis could be improved using positron emission tomography techniques in special conditions in which CT and EUS are not completely diagnostic.It is essential for clinicians to understand the advantages and disadvantages of the various pancreatic imaging modalities in order to be able to make optimal treatment and management decisions.Our study investigates the current role and innovative techniques of pancreatic imaging focused on the detection of pancreatic cancer.
文摘The aim of this study was to illustrate the role of noninvasive imaging tools such as ultrasonography,multidetector row computed tomography,and magnetic resonance imaging in the evaluation of pediatric and adult liver recipients and potential liver donors,and in the detection of potential complications arising from liver transplantation.
文摘AIM: To assess the diagnostic accuracy of multidetectorrow computed tomography(MDCT) as compared with conventional magnetic resonance imaging(MRI), in identifying mesorectal fascia(MRF) invasion in rectal cancer patients.METHODS: Ninety-one patients with biopsy proven rectal adenocarcinoma referred for thoracic and abdominal CT staging were enrolled in this study. The contrast-enhanced MDCT scans were performed on a 256 row scanner(ICT, Philips) with the following acquisition parameters: tube voltage 120 KV, tube current 150-300 m As. Imaging data were reviewed as axial and as multiplanar reconstructions(MPRs) images along the rectal tumor axis. MRI study, performed on 1.5 T with dedicated phased array multicoil, included multiplanar T2 and axial T1 sequences and diffusion weighted images(DWI). Axial and MPR CT images independently were compared to MRI and MRF involvement was determined. Diagnostic accuracy of both modalities was compared and statistically analyzed.RESULTS: According to MRI, the MRF was involved in 51 patients and not involved in 40 patients. DWI allowed to recognize the tumor as a focal mass with high signal intensity on high b-value images, compared with the signal of the normal adjacent rectal wall or with the lower tissue signal intensity background. The number of patients correctly staged by the native axial CT images was 71 out of 91(41 with involved MRF; 30 with not involved MRF), while by using the MPR 80 patients were correctly staged(45 with involved MRF; 35 with not involved MRF). Local tumor staging suggested by MDCT agreed with those of MRI, obtaining for CT axial images sensitivity and specificity of 80.4% and 75%, positive predictive value(PPV) 80.4%, negative predictive value(NPV) 75% and accuracy 78%; while performing MPR the sensitivity and specificity increased to 88% and 87.5%, PPV was 90%, NPV 85.36% and accuracy 88%. MPR images showed higher diagnostic accuracy, in terms of MRF involvement, than native axial images, as compared to the reference magnetic resonance images. The
文摘Myocardial pathologies are major causes of morbidity and mortality worldwide. Early detection of loss of cellular integrity and expansion in extracellular volume(ECV) in myocardium is critical to initiate effective treatment. The three compartments in healthy myocardium are: intravascular(approximately 10% of tissue volume), interstitium(approximately 15%) and intracellular(approximately 75%). Myocardial cells, fibroblasts and vascular endothelial/smooth muscle cells represent intracellular compartment and the main proteins in the interstitium are types Ⅰ/Ⅲ collagens. Microscopic studies have shown that expansion of ECV is an important feature of diffuse physiologic fibrosis(e.g., aging and obesity) and pathologic fibrosis [heart failure, aortic valve disease, hypertrophic cardiomyopathy, myocarditis, dilated cardiomyopathy, amyloidosis, congenital heart disease, aortic stenosis, restrictive cardiomyopathy(hypereosinophilic and idiopathic types), arrythmogenic right ventricular dysplasia and hypertension]. This review addresses recent advances in measuring of ECV in ischemic and non-ischemic myocardial pathologies. Magnetic resonance imaging(MRI) has the ability to characterize tissue proton relaxation times(T1, T2, and T2*). Proton relaxation times reflect the physical and chemical environments of water protons in myocardium. Delayed contrast enhanced-MRI(DE-MRI) and multi-detector computed tomography(DE-MDCT) demonstrated hyper-enhanced infarct, hypo-enhanced microvascular obstruction zone and moderately enhanced peri-infarct zone, but are limited for visualizing diffuse fibrosis and patchy microinfarct despite the increase in ECV. ECV can be measured on equilibrium contrast enhanced MRI/MDCT and MRI longitudinal relaxation time mapping. Equilibrium contrast enhanced MRI/MDCT and MRI T1 mapping is currently used, but at a lower scale, as an alternative to invasive sub-endomyocardial biopsies to eliminate the need for anesthesia, coronary catheterization and possibility of tissue sampling error. Similar to d
文摘The metal organic framework functionalized with sulfonic acid was combined with magnetic nanoparticles to fabricate a new nanocomposite(denoted as Fe3O4@PDA@Zr-SO3H).By combining with gas chromatography-electron capture detector,the resulting Fe3O4@PDA@Zr-SO3H nanocomposite was successfully used as a high-efficiency adsorbent for pre-concentrating eight organochlorine pesticides from water sample in environment.Apart from the ability of fast separation,the as-prepared Fe3O4@PDA@Zr-SO3H nanocomposite also exhibited high adsorption capacity for organochlorine pesticides.With the use of optimal experimental conditions,the linear relationship can be obtained in the range of 0.05~300μg/L,the correlation coefficient was over 0.9978,and the relative standard deviation was located in 2.5%-7.7%.Moreover,the limit of detection and quantification was between0.005-0.016μg/L and 0.017~0.050μg/L.Finally,the nanocomposite was used for the determination of organochlorine pesticides from environmental water samples,and displayed the recovery of 82%-118%.
文摘Radiation is considered one of the possible causes of cancer disease with natural background sources including cosmic, terrestrial and internal radiation. A number of cancer disease cases have been reported in Kargi with their causes not properly documented. The present work characterized the radioactivity in soil and water, to find out possible causes of radiation in KARGI-KENYA by studying magnetic intensities, anomalous zones with depth to magnetic sources and delineating subsurface structures. A total of 117 soil and 14 water samples were collected from the entire area and analysed for radionuclides due to <sup>40</sup>K, <sup>232</sup>Th and <sup>226</sup>Ra. Measurement methods of proton magnetometer and gamma spectrometry employing a high purity germanium (HPGe) detector were employed basically to evaluate the magnetic survey and radiological hazard of radioactivities respectively. A total of 51 magnetic field measurements were taken on the eastern part of Kargi, a place suspected to have more concentration of radionuclides. The results showed that there could have been a fractionation during weathering period or metasomatic activity of the radioelements involvement. This study also reveals that the mining activities in the nearby study area could have affected the geologic formation causing more fracturing in rocks and pronounced subsurface structures as a result of mining that could have served as passage for leachates from pollutants as well as the level of radiation in the study area.