Background and purpose:Gastric cancer impacts human health seriously. Accurate preoperative assessment of T staging and metastatic lymph nodes of gastric cancer was beneifcial to patients’ treatment options and their prognosis. The purpose of this study was to evaluate the diagnostic performance of diffusion-weighted magnetic resonance imaging for preoperative assessment of T staging and metastatic lymph nodes in patients with gastric cancer. Methods:This study selected 35 gastric cancer patients met the criteria for this prospective study. They all underwent gastric 3.0 T MRI+DWI imaging scan. These patients’ T stage and metastatic lymph nodes were evaluated before the surgery, with the reference of post-operative histopathological ifndings. Kappa consistency test was used to assess the consistency of T staging between the two methods. This study analyzed short axis diameter, long axis diameter and apparent diffusion coeffcient (ADC) values of lymph nodes, relative of muscle’s ADC (rADCm) values (rADCm=ADC values of lymph nodes/ADC values of right erector spinae), and relative of primary tumor’s ADC (rADCp) values (rADCp=ADC values of lymph nodes/ADC values of primary tumor) on MRI image. Independent samples test was used to assess the difference between metastatic lymph nodes and benign lymph nodes. The receiver operating characteristic(ROC) curve was generated to evaluate the accuracy of diffusion-weighted magnetic resonance imaging (MRI) for preoperative assessment of metastatic lymph nodes of gastric cancer.Results:The accuracy of diffusion-weighted MRI for T stages was 77.14%, 75% for T1, 100% for T2, 76.47% for T3 and 75.00% for T4 and respectively. There were statistically signiifcant differences in the long axis diameter, the short axis diameter, ADC value, rADCm and rADCp between metastatic lymph nodes and benign lymph nodes (P<0.05). The area under the ROC curve of rADCm was greater than thats of other criteria, so rADCm was the most signiifcant parameter. The best discriminative cut-off value of long axis, short axis, ADC value, rADCm value and rADCp value were 9.55 mm, 6.05 mm, 0.934×10-3mm2/s, 0.60 and 1.083, respectively. The sensitivity and speciifcity were 59.00% and 73.10%, 59.00% and 69.80%, 82.60% and 88.50%, 83.70% and 84.60%, 78.20% and 80.80%, respectively.Conclusion:Diffusion-weighted MRI has great signiifcance for preoperative assessment of T staging and metastatic lymph nodes of gastric cancer.

Objective:To evaluate the role of hippocampal β-amyloid 42 (Aβ 42) deposition-induced accumulation of neutrophils in blood-brain barrier damage caused by sevoflurane anesthesia in aged rats. Methods:Seventy-two healthy male Wistar rats in which IT catheters were successfully planted, aged 18-20 months, weighing 600-650 g, were divided into 4 groups ( n=18 each) using a random number table method: control group (group C), γ-secretase inhibitor DAPT group (group D), sevoflurane anesthesia group (group S) and DAPT plus sevoflurane anesthesia group (group DS). Dimethyl sulfoxide 10 μl was intrathecally injected in group C and group S, and 30 min later group C inhaled 60% oxygen for 2 h, and group S inhaled 3.6% sevoflurane and 60% oxygen for 2 h and tibial fracture surgery was performed at the same time.DAPT 10 μl was intrathecally injected in group D and group DS, and 30 min later group D inhaled 60% oxygen for 2 h, and group DS inhaled 3.6% sevoflurane and 60% oxygen for 2 h and tibial fracture surgery was performed at the same time.The fear conditioning test was performed at 12 h after the end of treatment in each group, and the ratio of time spent freezing was calculated.The rats were sacrificed after the end of behavioral test, and hippocampal tissues were removed for determination of the expression of Aβ 42, occludin and matrix metalloproteinase-9 (MMP-9) (by Western blot), neutrophil count (by immuno-histochemistry), and content of Evans blue (EB) (by EB staining). Results:Compared with group C, the ratio of time spent freezing was significantly decreased, the expression of Aβ 42 and MMP-9 was up-regulated, the expression of occludin was down-regulated, the neutrophil count and content of EB were increased in group S and group DS ( P<0.05), and no significant change was found in the parameters mentioned above in group D ( P>0.05). Compared with group S, the ratio of time spent freezing was significantly increased, the expression of Aβ 42 and MMP-9 was down-regulated, the expression of occludin was up-regulated, the neutrophil count and content of EB were decreased in group DS ( P<0.05). Conclusion:The mechanism by which sevoflurane anesthesia leads to postoperative cognitive dysfunction is related to hippocampal Aβ 42 deposition-induced accumulation of neutrophils and causing damage to blood-brain barrier in aged rats.

ObjectiveTo observe the effects of Hirudo， Notoginseng Radix et Rhizoma， and drug pair on renal pathological morphology and protein phosphatase 2A （PP2A）/adenylate activated protein kinase （AMPK）/mammalian target of rapamycin （mTOR） signal pathway in rats with chronic renal failure （CRF）. MethodThe 55 male SD rats were randomly divided into a normal group （n=11） and a modeling group （n=44）. The normal group was fed conventionally， and the modeling group was given 0.25 g·kg^-1·d^-1 adenine by gavage for 28 days to replicate the CRF model. After successful modeling， rats were randomly divided into model group， Hirudo group （3 g·kg^-1·d^-1）， Notoginseng Radix et Rhizoma group （3 g·kg^-1·d^-1）， and Hirudo + Notoginseng Radix et Rhizoma group （3 g·kg^-1·d^-1）， with 9 rats in each group. The normal group and model group were given a constant volume of normal saline by intragastric administration for 30 days. At the end of the experiment， the levels of serum creatinine （SCr） and urea nitrogen （BUN） in all groups were measured. The renal pathological morphology changes were observed by hematoxylin-eosin （HE） staining， Masson staining， and electron microscopy. The mRNA expressions of PP2A， AMPK， and mTOR were detected by Real-time fluorescence quantitative polymerase chain reaction （Real-time PCR）. The protein expression levels of PP2A， AMPK， phosphorylation（p）-AMPK， mTOR， and p-mTOR in renal tissue were detected by Western blot. ResultCompared with the normal group， the renal pathological structure changes were obvious， and the levels of SCr and BUN were significantly increased. The mRNA expression of PP2A， protein expression of PP2A， and p-mTOR/mTOR expression were significantly increased， and the p-AMPK/AMPK was significantly decreased in the model group （P<0.05）. Compared with the model group， the renal pathological morphology changes were significantly improved， and the levels of SCr and BUN were significantly decreased. The mRNA expression of PP2A， protein expression of PP2A， and p-mTOR/mTOR expression in the renal tissue were significantly decreased， and the p-AMPK/AMPK was significantly increased （P<0.05） in all groups after drug intervention. In addition， the effect in the Hirudo+Notoginseng Radix et Rhizoma group was better. The mRNA expression levels of AMPK and mTOR in the renal tissue were not significantly different among the normal group， model group， and other groups. ConclusionThe efficacy of Hirudo and Notoginseng Radix et Rhizoma pairs in improving renal fibrosis in rats with CRF is significantly better than that of the single drug， and its improvement on renal fibrosis in rats with CRF may be related to the regulation of PP2A/AMPK/mTOR signaling pathway.