Diagnostic value of multislice spiral CT and MRI in detection of tumor recurrence after liver transplantation for hepatocellular carcinoma / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To investigate the manifestation and diagnostic value of multislice spiral CT (MSCT) and MRI imaging in detection of tumor recurrence after liver transplantation for hepatocellular carcinoma (HCC).</p><p><b>METHODS</b>The clinical data of 161 consecutive HCC patients who underwent orthotopic liver transplantation were retrospectively reviewed. Twenty-nine HCC patients were classified by pTNM according to the "Pittsburgh criteria". MSCT and MRI findings of tumor recurrence after liver transplantation were evaluated retrospectively in 29 stage II-IVb HCC patients. The recurrence site and relapse interval between liver transplantation and recurrence were analyzed.</p><p><b>RESULTS</b>Lung tumor recurrence were found in 21 cases, presented as cotton-like lesions in a diameter of 2 - 3 cm, with a clear margin and homogeneous density. Pleural tumor recurrence was detected in 4 cases. Liver tumor recurrence were found in 9 cases, which can be divided into four subtypes: multinodular in 4 cases, diffuse lesion in 2 cases, huge mass in 2 cases, and uninodular in 1 case. Two cases showed tumor thrombus in the inferior vena cava and portal vein. Lymph node tumor recurrence was found in 9 cases, presented as multiple nodules at hepatic hilum, lesser peritoneal sac, posterior mediastinum, retroperitoneum, or around pancreatic head, and accompanied with merging and necrosis in one case. Bone tumor recurrence were found as osteolytic destruction in 4 cases, and accompanied with adjacent soft-tissue mass in 2 cases. The recurrence sites of the 29 cases were as following: lung (21 cases, 72.4%), liver (9 cases, 31.0%), lymph nodes (9 cases, 31.0%), bone (4 cases, 13.8%) and other sites (3 cases, 10.3%). Lung tumor recurrence was found in all the 10 stage IVb patients with tumor recurrence after liver transplantation, significantly more frequent than that in stage IVa patients (P = 0.023). After liver transplantation, all 25 patients with stage III approximately IVb HCC developed recurrence within one year, but in the 4 cases with stage II HCC at one year later (P = 0.009).</p><p><b>CONCLUSION</b>The results of our study show that in hepatocellular carcinoma patients after liver transplantation, the lung and pleura are the most frequent site of recurrence, followed by liver, lymph node and bone as the second and third sites. The Stage IVb hepatocellular carcinoma should be regarded as a contradiction for liver transplantation due to rapid recurrence. Tumor recurrence occurs later in stage II HCC than in stage III approximately IVb patients. MSCT and MRI are of significant importance in diagnosis and formulating operation plan in HCC patients with recurrence after liver transplantation.</p>

Inhibitory effect of unaggregated amyloid beta protein (25-35) on delayed rectifier potassium current in rat hippocampal CA3 pyramidal neurons / 中国医学科学院学报

<p><b>OBJECTIVE</b>To investigate the effect of unaggregated Abeta(25.35) on delayed rectifier potassium current (I(K)) in neonatal rat hippocampal CA3 pyramidal neurons.</p><p><b>METHODS</b>The rat hippocampal neurons were enzymatically isolated from 10-11-day-old Wistar rat. The I(K) was recorded using whole-cell patch clamp technique.</p><p><b>RESULTS</b>The inhibitory effect of unaggregated Abeta(25-35) on I(K) was time-dependent, because I(K) significantly decreased from (6.987 +/- 1.152) nA to (2.540 +/- 0.349) nA after adding unaggregated Abeta(25-35) and reached a stabilized level after 5-7 min (n = 8, P <0.01). However, the inhibitory effect was not concentration-dependent, because the decrease of the I(K) amplitude in different concentration groups were all around 60%. Unaggregated Abeta(25-35) also remarkably affected the half-activation potential, which was (4.114 +/- 0.730) mV and (-5.463 +/- 0.950) mV before and after its application (n = 15, P <0.05); however, the slope factor of activation curve was not significantly changed.</p><p><b>CONCLUSION</b>The inhibitory effect of unaggregated Abeta(25-35) on I(K) may be a possible mechanism involved in the pathogenesis of Alzheimer's disease.</p>

Effects of beta-cypermethrin on voltage-gated potassium channels in rat hippocampal CA3 neurons / 生理学报

The effects of beta-cypermethrin (consisting of alpha-cypermethrin and theta-cypermethrin) on the transient outward potassium current (I(A)) and delayed rectifier potassium current (I(K)) in freshly dissociated hippocampal CA3 neurons of rats were studied using whole-cell patch-clamp technique. The results indicated that alpha-cypermethrin increased the value of I(A) and theta-cypermethrin decreased the value of I(A), though both of them shifted steady activation curve of I(A) towards negative potential. theta-cypermethrin contributed to the inactivation of I(A). The results also showed that alpha-cypermethrin and theta-cypermethrin decreased the value of I(K), and shifted the steady state activation curve of I(K) towards negative potential. Both alpha-cypermethrin and theta-cypermethrin had no obvious effects on the inactivation of I(K). theta-cypermethrin prolonged recovery process of I(K). These results imply that both transient outward potassium channels and delayed rectified potassium channels are the targets of beta-cypermethrin, which may explain the mechanism of toxical effects of beta-cypermethrin on mammalian neurons.

Diffusion tensor imaging and three-dimensional brain fiber tracking for the diagnosis of multiple sclerosis / 中华放射学杂志

Objective To demonstrate the diffusion tensor imaging(DTI)characteristics of multiple sclerosis(MS)plaques,periplaque white matter regions and normal appearing white matter (NAWM)regions in patients with MS,and to evaluate the clinical values of DTI and three-dimensional brain fiber tracking for the diagnosis of MS.Methods Conventional MRI and DTI were performed in 32 patients with MS and 32 age-matched control subjects.Fractional anisotropy(FA)and apparent diffusion coefficient(ADC)maps were generated and coregistered with T_2-weighted MR images,FA and ADC values were calculated in regions of interest in plaques,periplaque white matter regions,NAWM regions and white matter regions in control subjects.And three-dimensional brain fiber tracking maps were generated by using the DTI.Results TheADCwas(1.233?0.119)?10~(-3)mm~2/s in MS plaques,(0.973?0.098)?10~(-3) mm~2/s in periplaque white matter regions,(0.748?0.089)?10~(-3)mm~2/s in NAWM,and(0.620? 0.094)?10~(-3)mm~2/s in control subjects.The FA was 0.225?0.052 in MS plaques,0.311?0.050 in perip]aque white matter regions,0.421?0.070 in NAWM,and 0.476?0.069 in control subjects. Significant differences in FA and ADC values were observed among all white matter regions(P