AIM: To investigate the clinical role of contrast-enhanced ultrasound (CEUS) combined with contrast-enhanced computed tomography (CE-CT) or magnetic resonance imaging to improve the preoperative staging of hepatocellu...AIM: To investigate the clinical role of contrast-enhanced ultrasound (CEUS) combined with contrast-enhanced computed tomography (CE-CT) or magnetic resonance imaging to improve the preoperative staging of hepatocellular carcinoma (HCC) and guide surgical decision-making. METHODS: Sixty-nine patients who underwent liver resection for HCC in our center were enrolled prospectively in the study. CEUS and CE-CT/MRI were performed before surgery. Intraoperative ultrasound (IOUS) was carried out after liver mobilization. Lesions depicted by each imaging modality were counted and mapped. To investigate the impact of tumor size on the study, we divided the patients into two groups, the 'Smaller group'(S-group, <= 5 cm in diameter) and the 'Largergroup' (L-group, > 5 cm in diameter). The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of CE-CT/MRI, CEUS, IOUS, CEUS+CE-CT/MRI and the tumor node metastasis staging of tumors were calculated and compared. Changes in the surgical strategy as a result of CEUS and IOUS were analyzed. RESULTS: One hundred and twenty-seven nodules, comprising 94 HCCs confirmed by histopathology and 33 benign lesions confirmed by histopathology and follow-up, were identified in 69 patients. The overall diagnostic sensitivity rates of CE-CT/MRI, CEUS, IOUS and CEUS+ CE-CT/MRI were 78.7%, 89.4%, 89.4% and 89.4%, respectively. There was a significant difference between CEUS + CE-CT/MRI and CE-CT/MRI (P = 0.046). Combining CEUS with CT or MRI increased, the diagnostic specificity compared with CT/MRI, CEUS and IOUS, and this difference was statistically significant (100%, 72.7%, 97.0%, and 69.7%, P = 0.004, P = 0.002, P = 0.002, respectively). The diagnostic accuracy was significantly higher for CEUS + CT/MRI compared with CT/MRI (92.1% vs 77.2%, P = 0.001). The TNM staging of tumors based on CEUS + CE-CT/MRI approximated to the final pathological TNM staging (P = 0.977). There was a significant difference in the accuracy of TNM staging when comparing CEUS +展开更多
AIM: To investigate the effect of vascular endothelial growth factor (VEGF) transfection on hepatic sinusoidal capillarization. METHODS: Enhanced green fluorescent protein (EGFP)/ VEGF transfection was confirmed by im...AIM: To investigate the effect of vascular endothelial growth factor (VEGF) transfection on hepatic sinusoidal capillarization. METHODS: Enhanced green fluorescent protein (EGFP)/ VEGF transfection was confirmed by immunofluorescence microscopy and immunohistoche-mistry both in primary hepatocytes and in normal liver. Cirrhotic rats were generated by thioacetamide (TAA) administration and then divided into a treatment group, which received injections of 400 μg of plasmid DNA encoding an EGFP- VEGF fusion protein, and a blank group, which received an equal amount of normal saline through the portal vein. The portal vein pressure was measured in the normal and cirrhotic state, in treated and blank groups. The average number of fenestrae per hepatic sinusoid was determined using transmission electron microscopy (TEM), while the relative abundance of VEGF transcripts was examined by Gene array. RESULTS: Green fluorescent protein was observed in the cytoplasms of liver cells under immunofluorescence microscopy 24 h after transfection with EGFP/VEGF plasmid in vitro. Staining with polyclonal antibodies against VEGF illustrated that hepatocytes expressedimmunodetectable VEGF both in vitro and in vitro. There were significant differences in the number of fenestrae and portal vein pressures between normal and cirrhotic rats (7.40 ± 1.71 vs 2.30 ± 1.16 and 9.32 ± 0.85 cmH2O vs 17.92 ± 0.90 cmH2O, P < 0.01), between cirrhotic and treated rats (2.30 ± 1.16 cmH2O vs 4.60 ± 1.65 and 17.92 ± 0.90 cmH2O vs 15.52 ± 0.93 cmH2O, P < 0.05) and between the treatment group and the blank group (4.60 ± 1.65 cmH2O vs 2.10 ± 1.10 cmH2O and 15.52 ± 0.93 cmH2O vs 17.26 ± 1.80 cmH2O, P < 0.05). Gene- array analysis revealed that the relative abundance of transcripts of VEGF family members decreased in the cirrhotic state and increased after transfection. CONCLUSION: Injection of a plasmid encoding VEGF through the portal vein is an effective method to induce the formation of fenestrae and decrease portal vein pressure in cirrhot展开更多
Crown roots are main components of the fibrous root system and important for crops to anchor and absorb water and nutrition. To understand the molecular mechanisms of crown root formation, we isolated a rice mutant de...Crown roots are main components of the fibrous root system and important for crops to anchor and absorb water and nutrition. To understand the molecular mechanisms of crown root formation, we isolated a rice mutant defective in crown root emergence designated as Oscand1 (named after the Arabidopsis homologous gene AtCAND1). The defect of visible crown root in the Oscandl mutant is the result of cessation of the G2/M cell cycle transition in the crown root meristem. Map-based cloning revealed that OsCAND1 is a homolog ofArabidopsis CAND1. During crown root primordium development, the expression of OsCAND1 is confined to the root cap after the establishment of fundamental organization. The transgenic plants harboring DRS::GUS showed that auxin signaling in crown root tip is abnormal in the mutant. Exogenous auxin application can partially rescue the defect of crown root development in Oscandl. Taken together, these data show that O5CAND1 is involved in auxin signaling to maintain the G2/M cell cycle transition in crown root meristem and, consequently, the emergence of crown root. Our findings provide new information about the molecular regulation of the emergence of crown root in rice.展开更多
Background:Neuroimaging studies have found that functional changes exist in patients with Parkinson's disease (PD).However,the majority of functional magnetic resonance imaging (fMRI) studies in patients with PD...Background:Neuroimaging studies have found that functional changes exist in patients with Parkinson's disease (PD).However,the majority of functional magnetic resonance imaging (fMRI) studies in patients with PD are task-related and cross-sectional.This study investigated the functional changes observed in patients with PD,at both baseline and after 2 years,using resting-state fMRI.It further investigated the relationship between whole-brain spontaneous neural activity of patients with PD and their clinical characteristics.Methods:Seventeen patients with PD underwent an MRI procedure at both baseline and after 2 years using resting-state fMRI that was derived from the same 3T MRI.In addition,20 age-and sex-matched,healthy controls were examined using resting-state fMRI.The fractional amplitude of low-frequency fluctuation (fALFF) approach was used to analyze the fMRI data.Nonlinear registration was used to model within-subject changes over the scanning interval,as well as changes between the patients with PD and the healthy controls.A correlative analysis between the fALFF values and clinical characteristics was performed in the regions showing fALFF differences.Results:Compared to the control subjects,the patients with PD showed increased fALFF values in the left inferior temporal gyrus,right inferior parietal lobule (IPL) and right middle frontal gyrus.Compared to the baseline in the 2 years follow-up,the patients with PD presented with increased fALFF values in the right middle temporal gyrus and right middle occipital gyrus while also having decreased fALFF values in the right cerebellum,right thalamus,right striatum,left superior parietal lobule,left IPL,left precentral gyrus,and left postcentral gyrus (P 〈 0.01,after correction with AlphaSim).In addition,the fALFF values in the right cerebellum were positively correlated with the Unified PD Rating Scale (UPDRS) motor scores (r =0.5 l,P 〈 0.05,uncorrected) and the change in the UPDRS motor score (r =0.61,P 〈 0.05,u展开更多
Nitrogen (N) cycling in boreal peatland ecosystems may be influenced in important ways by freeze-thaw cycles (FTCs). Adsorption and desorption of ammonium ions (NH4+) were examined in a controlled laboratory ex...Nitrogen (N) cycling in boreal peatland ecosystems may be influenced in important ways by freeze-thaw cycles (FTCs). Adsorption and desorption of ammonium ions (NH4+) were examined in a controlled laboratory experiment for soils sampled from palustrine wetland, riverine wetland, and farmland reclaimed from natural wetland in response to the number of FTCs. The results indicate that freeze-thaw significantly increased the adsorption capacity of NH: and reduced the desorption potential of NH4+ in the wetland soils. There were significant differences in the NH4+ adsorption amount between the soils with and without freeze-thaw treatment. The adsorption amount of NH4+ increased with increasing FTCs. The palustrine wetland soil had a greater adsorption capacity and a weaker desorption potential of NH4+ than the riverine wetland soil because of the significantly higher clay content and cation exchange capacity (CEC) of the riverine wetland soil. Because of the altered soil physical and chemical properties and hydroperiods, the adsorption capacity of NH4+ was smaller in the farmland soil than in the wetland soils, while the desorption potential of the farmland soil was higher than that of the wetland soils. Thus, wetland reclamation would decrease adsorption capacity and increase desorption potential of NH4+, which could result in N loss from the farmland soil. FTCs might mitigate N loss from soils and reduce the risk of water pollution in downstream ecosystems.展开更多
基金Supported by A Grant from the National Sciences and Technology Major Project of China NO.2012ZX10002-016 and NO.2012ZX10002-017
文摘AIM: To investigate the clinical role of contrast-enhanced ultrasound (CEUS) combined with contrast-enhanced computed tomography (CE-CT) or magnetic resonance imaging to improve the preoperative staging of hepatocellular carcinoma (HCC) and guide surgical decision-making. METHODS: Sixty-nine patients who underwent liver resection for HCC in our center were enrolled prospectively in the study. CEUS and CE-CT/MRI were performed before surgery. Intraoperative ultrasound (IOUS) was carried out after liver mobilization. Lesions depicted by each imaging modality were counted and mapped. To investigate the impact of tumor size on the study, we divided the patients into two groups, the 'Smaller group'(S-group, <= 5 cm in diameter) and the 'Largergroup' (L-group, > 5 cm in diameter). The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of CE-CT/MRI, CEUS, IOUS, CEUS+CE-CT/MRI and the tumor node metastasis staging of tumors were calculated and compared. Changes in the surgical strategy as a result of CEUS and IOUS were analyzed. RESULTS: One hundred and twenty-seven nodules, comprising 94 HCCs confirmed by histopathology and 33 benign lesions confirmed by histopathology and follow-up, were identified in 69 patients. The overall diagnostic sensitivity rates of CE-CT/MRI, CEUS, IOUS and CEUS+ CE-CT/MRI were 78.7%, 89.4%, 89.4% and 89.4%, respectively. There was a significant difference between CEUS + CE-CT/MRI and CE-CT/MRI (P = 0.046). Combining CEUS with CT or MRI increased, the diagnostic specificity compared with CT/MRI, CEUS and IOUS, and this difference was statistically significant (100%, 72.7%, 97.0%, and 69.7%, P = 0.004, P = 0.002, P = 0.002, respectively). The diagnostic accuracy was significantly higher for CEUS + CT/MRI compared with CT/MRI (92.1% vs 77.2%, P = 0.001). The TNM staging of tumors based on CEUS + CE-CT/MRI approximated to the final pathological TNM staging (P = 0.977). There was a significant difference in the accuracy of TNM staging when comparing CEUS +
基金The National Natural Science Fundation of China, No. 30300341The Natural Science Fundation of Shandong Province, No. Y2004Z12
文摘AIM: To investigate the effect of vascular endothelial growth factor (VEGF) transfection on hepatic sinusoidal capillarization. METHODS: Enhanced green fluorescent protein (EGFP)/ VEGF transfection was confirmed by immunofluorescence microscopy and immunohistoche-mistry both in primary hepatocytes and in normal liver. Cirrhotic rats were generated by thioacetamide (TAA) administration and then divided into a treatment group, which received injections of 400 μg of plasmid DNA encoding an EGFP- VEGF fusion protein, and a blank group, which received an equal amount of normal saline through the portal vein. The portal vein pressure was measured in the normal and cirrhotic state, in treated and blank groups. The average number of fenestrae per hepatic sinusoid was determined using transmission electron microscopy (TEM), while the relative abundance of VEGF transcripts was examined by Gene array. RESULTS: Green fluorescent protein was observed in the cytoplasms of liver cells under immunofluorescence microscopy 24 h after transfection with EGFP/VEGF plasmid in vitro. Staining with polyclonal antibodies against VEGF illustrated that hepatocytes expressedimmunodetectable VEGF both in vitro and in vitro. There were significant differences in the number of fenestrae and portal vein pressures between normal and cirrhotic rats (7.40 ± 1.71 vs 2.30 ± 1.16 and 9.32 ± 0.85 cmH2O vs 17.92 ± 0.90 cmH2O, P < 0.01), between cirrhotic and treated rats (2.30 ± 1.16 cmH2O vs 4.60 ± 1.65 and 17.92 ± 0.90 cmH2O vs 15.52 ± 0.93 cmH2O, P < 0.05) and between the treatment group and the blank group (4.60 ± 1.65 cmH2O vs 2.10 ± 1.10 cmH2O and 15.52 ± 0.93 cmH2O vs 17.26 ± 1.80 cmH2O, P < 0.05). Gene- array analysis revealed that the relative abundance of transcripts of VEGF family members decreased in the cirrhotic state and increased after transfection. CONCLUSION: Injection of a plasmid encoding VEGF through the portal vein is an effective method to induce the formation of fenestrae and decrease portal vein pressure in cirrhot
文摘Crown roots are main components of the fibrous root system and important for crops to anchor and absorb water and nutrition. To understand the molecular mechanisms of crown root formation, we isolated a rice mutant defective in crown root emergence designated as Oscand1 (named after the Arabidopsis homologous gene AtCAND1). The defect of visible crown root in the Oscandl mutant is the result of cessation of the G2/M cell cycle transition in the crown root meristem. Map-based cloning revealed that OsCAND1 is a homolog ofArabidopsis CAND1. During crown root primordium development, the expression of OsCAND1 is confined to the root cap after the establishment of fundamental organization. The transgenic plants harboring DRS::GUS showed that auxin signaling in crown root tip is abnormal in the mutant. Exogenous auxin application can partially rescue the defect of crown root development in Oscandl. Taken together, these data show that O5CAND1 is involved in auxin signaling to maintain the G2/M cell cycle transition in crown root meristem and, consequently, the emergence of crown root. Our findings provide new information about the molecular regulation of the emergence of crown root in rice.
文摘Background:Neuroimaging studies have found that functional changes exist in patients with Parkinson's disease (PD).However,the majority of functional magnetic resonance imaging (fMRI) studies in patients with PD are task-related and cross-sectional.This study investigated the functional changes observed in patients with PD,at both baseline and after 2 years,using resting-state fMRI.It further investigated the relationship between whole-brain spontaneous neural activity of patients with PD and their clinical characteristics.Methods:Seventeen patients with PD underwent an MRI procedure at both baseline and after 2 years using resting-state fMRI that was derived from the same 3T MRI.In addition,20 age-and sex-matched,healthy controls were examined using resting-state fMRI.The fractional amplitude of low-frequency fluctuation (fALFF) approach was used to analyze the fMRI data.Nonlinear registration was used to model within-subject changes over the scanning interval,as well as changes between the patients with PD and the healthy controls.A correlative analysis between the fALFF values and clinical characteristics was performed in the regions showing fALFF differences.Results:Compared to the control subjects,the patients with PD showed increased fALFF values in the left inferior temporal gyrus,right inferior parietal lobule (IPL) and right middle frontal gyrus.Compared to the baseline in the 2 years follow-up,the patients with PD presented with increased fALFF values in the right middle temporal gyrus and right middle occipital gyrus while also having decreased fALFF values in the right cerebellum,right thalamus,right striatum,left superior parietal lobule,left IPL,left precentral gyrus,and left postcentral gyrus (P 〈 0.01,after correction with AlphaSim).In addition,the fALFF values in the right cerebellum were positively correlated with the Unified PD Rating Scale (UPDRS) motor scores (r =0.5 l,P 〈 0.05,uncorrected) and the change in the UPDRS motor score (r =0.61,P 〈 0.05,u
基金Supported by the Knowledge Innovation Program of the Chinese Academy of Sciences (No. KZCX2-YW-309)the National Natural Science Foundation of China (Nos. 40830535 and 40871089)
文摘Nitrogen (N) cycling in boreal peatland ecosystems may be influenced in important ways by freeze-thaw cycles (FTCs). Adsorption and desorption of ammonium ions (NH4+) were examined in a controlled laboratory experiment for soils sampled from palustrine wetland, riverine wetland, and farmland reclaimed from natural wetland in response to the number of FTCs. The results indicate that freeze-thaw significantly increased the adsorption capacity of NH: and reduced the desorption potential of NH4+ in the wetland soils. There were significant differences in the NH4+ adsorption amount between the soils with and without freeze-thaw treatment. The adsorption amount of NH4+ increased with increasing FTCs. The palustrine wetland soil had a greater adsorption capacity and a weaker desorption potential of NH4+ than the riverine wetland soil because of the significantly higher clay content and cation exchange capacity (CEC) of the riverine wetland soil. Because of the altered soil physical and chemical properties and hydroperiods, the adsorption capacity of NH4+ was smaller in the farmland soil than in the wetland soils, while the desorption potential of the farmland soil was higher than that of the wetland soils. Thus, wetland reclamation would decrease adsorption capacity and increase desorption potential of NH4+, which could result in N loss from the farmland soil. FTCs might mitigate N loss from soils and reduce the risk of water pollution in downstream ecosystems.