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<p><b>BACKGROUND</b>Orthotopic liver transplantation (OLT) has become the therapeutic option of choice for end-stage liver disease. The aim of this study was to investigate the changes of splenic morphology, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), apparent diffusion coefficient (ADC) values and explore their value in evaluating the therapeutic effects of orthotopic liver transplantation (OLT) on portal hypertension at 1.5 Tesla MRI.</p><p><b>METHODS</b>Twenty patients with portal hypertension undergoing OLT were included in this study. Conventional MRI and diffusion-weighted image (DWI) (b value = 600 s/mm(2)) sequences were applied on each patient before and after OLT, and these patients were referred to as the preoperative and postoperative groups. Twenty healthy individuals were selected as the normal group. After image acquisition, the splenic width (W), thickness (T), length (L), the diameter of the portal vein (PD) and splenic vein (SD) were measured and the splenic volume (V) was calculated. The SNR and CNR were measured on T2WI. The ADC maps were calculated using the b600 in DWIs and the ADC values were measured.</p><p><b>RESULTS</b>Compared with the preoperative group, the splenic V, PD and SD decreased significantly in the postoperative group (P < 0.05). All splenic morphological values were significantly different between preoperative and normal groups (P < 0.05). The splenic L and V were significantly different (P < 0.05) between postoperative and normal groups. The SNR and CNR values were 17.66 ± 4.62 and 13.18 ± 3.12, 11.50 ± 1.64 and 7.44 ± 4.32, 4.24 ± 1.24 and 3.03 ± 2.41 in the preoperative, postoperative and normal groups, respectively. Both SNR and CNR decreased after OLT, but they was still higher than the normal values. The SNR was significantly different between any two groups (P < 0.05). The CNR was significantly different (P < 0.05) between the preoperative and postoperative groups, preoperative and normal groups. The splenic ADC values were (1.339 ± 0.482) × 10(-3) mm(2)/s, (1.120 ± 0.254) × 10(-3) mm(2)/s and (0.997 ± 0.447) × 10(-3) mm(2)/s in the preoperative, postoperative and normal groups, respectively. The difference of ADC values were significant (P < 0.05) between the preoperative and postoperative groups, and the preoperative and normal groups.</p><p><b>CONCLUSIONS</b>OLT is an effective method of treatment for portal hypertension. In addition to dramatically decreasing the splenic V, it can also decrease the splenic SNR, CNR and ADC values in patients with portal hypertension. The changes of splenic SNR, CNR and ADC after OLT may be helpful in providing noninvasive supplementary information in assessing the therapeutic effect of OLT on portal hypertension.</p>
Subject(s)
Adult , Aged , Female , Humans , Male , Middle Aged , Hypertension, Portal , Diagnosis , General Surgery , Liver Transplantation , Magnetic Resonance Imaging , Methods , Retrospective Studies , Splenomegaly , Diagnosis , General SurgeryABSTRACT
Objective To study the imaging apperances and the diagnostic value of conventional magnetic resonance imaging (MRI) and diffusion-weighted imaging (DWI) in differentiating histopathological types of small hepatocellular carcinoma (sHCC).Methods 40 sHCC confirmed by histopathology were classified into 4 groups according to their degree of differentiation:well (n=6),well-moderate (n=5),moderate (n=27) and moderate-poor (n =2).All patients received conventional MRI and DWI (1.5T,b =0 and 600 s/mm2) before the operation.The ADC values of the sHCC were measured and compared.Results On T1WI,32 lesions showed hypointensity,4 hyperintensity (well) and 4 isointensity (well-moderate =2,moderate =2).On T2WI,hyperintensity was observed in 39 lesions and isointensity in 1 lesion (well).Steatosis in the sHCC was seen in 17 of 40lesions (17/40,42.5 ％,well=4,well-moderate=1 and moderate=12).A pseudocapsule was seen in 67.5 ％ sHCC (27/40,well=4,well-moderate=3,moderate=18 and moderate-poor=2).32 lesions showed hypervascularity on arterial phase,and 8 lesions showed hypovascularity (well=3,moderate =4,moderate-poor=1).On DWI,37 lesions showed hyperintensity,except for 3 lesions with welldifferentiated sHCC which showed isointensity (50％,3/6).The mean ADC values±S.D.of sHCC in the well,well-moderate,moderate and moderate-poor groups were (1.757 ± 0.337) × 10-3,(1.917±0.574)×103,(1.816±0.545)×103 and (1.723±0.217)×10-3,respectively.There were no significant differences among the 4 groups.Conclusion The imaging appearances of wellmoderate,moderate and moderate-poor sHCC on conventional MRI were classical which make diagnosis easy.Hyperintensity on DWI contributed to diagnosis.However,the imaging appearances of some well-differentiated sHCC were atypical.The lesions could be isointensity or hyperintensity on DWI.The combination of conventional MRI and DWI contributed to better diagnosis of sHCC,especial for atypical sHCC.
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Objective To observe the effect of amylin on the islet β-cells voltage-gated L-calcium channels in rats. Method Patch clamp technique was employed in the observation of the features and changes of electric current of islet β-cells voltage-gated L-calcium channels before and after using amylin. Results In the glucose environment of 5. 5 mmoL/L, the electric current of rat islet β-cells voltage-gated L-calcium channels was activated at-40 mV and reached the peak at about +20 mV, with a peak value of about-120 pA and the insulin secretion level was(0. 76±0. 12) μg/L. Under the stimulation of glucose of 16. 7 mmol/L, the peak current voltage moved to the left and increased up to-140 pA and the level of insulin secretion measured (1.78±0. 13) μg/L. Hatch islet β-cells in amylin at the concentrations of 0. 5, 1.0, 5.0 and 10.0 μmol/L, respectively. It was observed that in the 0. 5 μmol/L and 1.0 μmol/L groups,there was no remarkable change in the peak potential activation voltage, current, and insulin secretion volume in comparison with the control group. However, in the environment of 5.5 mmol/L glucose, the increase of activation voltage of the 5.0 and 10.0 μmol/L groups was-30 mV, with the peak current reduced to approximately-80 pA and-60 pA and the insulin secretion decreased to (0. 49±0. 11) μg/L and (0. 36±0. 12) μg/L respectively. Under the concentration of 16. 7 mmol/L glucose, the activation voltage increased from-40 mV up to-30 mV and the peak current reduced to-80 pA and-40 pA. In the meantime, the insulin secretion decreased respectively to (1.20±0. 13) μg/L and (0. 89±0. 14) μg/L, which is of significance. Conclusion The secretion of insulin is synchronized with the opening of the islet β-cells voltage-gated L-calcium channels at the stimulation of glucose. The amylin inhibition of the insulin secretion is also synchronized with the opening of islet β-cells voltage-gated L-calcium channels and it's in a positive concentration-dependent manner.
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Objective To compare the values of biochemistry, ultrasonography ( US) , computed tomography(CT) and proton magnetic resonance spectroscopy ('H MRS) in the quantitative diagnosis of fatty liver. Methods Forty-five healthy New Zealand rabbits were enrolled in the study. Hepatic steatosis models were established by giving high fat, high sugar diet with drinking water containing five percent ethanol. Eighteen variable indexes were measured by biochemical examination, US,CT and ' H MRS. ROC analysis and Z test were used to compare the diagnostic efficacy of different clinical examinations. Results Among eighteen variable indexes,serum TC,ultrasound attenuation coefficient,liver CT value and ' H MRS fat peak area had the highest degree of relationship by biochemical examination, US, CT, ' H MRS in diagnosis of fatty liver, correlation coefficients were 0.886,0.483, -0. 764, 0. 558, and areas under curve were 0. 981, 0. 581, 0. 810, 0. 713, respectively. There were significant differences in areas under curve between every two groups except 'H MRS fat peak area and ultrasound attenuation coefficient, liver CT value. Conclusions The diagnostic values of imaging modalities in the hepatic steatosis grade, their order is CT >'H MRS> US; Serum TC maybe have important diagnostic value in evaluating hepatic steatosis grade,this is very worth further studying.
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0.05). - 40 mV activated threshold potential and - 30 mV peak potential for control group respectively droppedto - 60 mV and - 40 mV after irradiating 7 min. The half-activation voltage and the slope factor of the activationcurves of Na+ channel were also changed by the laser's exposure. The former changed from (- 42.091 ?1.537) mVto (54.971 ?1.846) mV (n= 8, P
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Objective To investigate the effects of unaggregated amyloid ? protein(A?25～35) on transient outward potassium channel(IA) in Rat Hippocampal CA3 Pyramidal Neurons.Methods Patch-clamp technique with whole cell recording was used.Results Unaggregated A?25～35 inhibited IA in neonatal rat hippocampal CA3 pyramidal neurons and displayed a time-,concentration- and voltage-dependent manner;the dynamic characteristics of IA were influenced:shifted the steady-state activation and inactivation curves to left significantly.Conclusion These results suggest that the inhibition of unaggregated A?25-35 on transient outward potassium channel in acutely isolated hippocampal CA3 pyramidal neurons may be an important mechanism of its toxicity,which participates in pathological changes of AD.