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.

Background and objective Mediastinal involvement in lung cancer is a highly significant prognostic fac-tor for survival, and accurate staging of the mediastinum will correctly identify patients who will benefit the most from surgery. Positron emission tomography/computed tomography (PET/CT) has become the standard imaging modality for the staging of patients with lung cancer. e aim of this study is to investigate 18-fluoro-2-deoxy-glucose (18F-FDG) PET/CT imaging in the detection of mediastinal disease in lung cancer. Methods A total of 72 patients newly diagnosed with non-small cell lung cancer (NSCLC) who underwent preoperative whole-body 18F-FDG PET/CT were retrospectively included. All patients underwent radical surgery and mediastinal lymph node dissection. Mediastinal disease was histologically confirmed in 45 of 413 lymph nodes. PET/CT doctors analyzed patients’ visual images and evaluated lymph node’s short axis, lymph node’s maxi-mum standardized uptake value (SUVmax), node/aorta density ratio, node/aorta SUV ratio, and other parameters using the histopathological results as the reference standard. e optimal cutovalue for each ratio was determined by receiver operator characteristic curve analysis. Results Using a threshold of 0.9 for density ratio and 1.2 for SUV ratio yielded high accuracy for the detection of mediastinal disease. e lymph node’s short axis, lymph node’s SUVmax, density ratio, and SUV ratio of integrated PET/CT for the accuracy of diagnosing mediastinal lymph node was 95.2%. e diagnostic accuracy of mediastinal lymph node with conventional PET/CT was 89.8%, whereas that of PET/CT comprehensive analysis was 90.8%. Conclusion Node/aorta density ratio and SUV ratio may be complimentary to conventional visual interpretation and SUVmax measure-ment. e use of lymph node’s short axis, lymph node’s SUVmax, and both ratios in combination is beer than either conven-tional PET/CT analysis or PET/CT comprehensive analysis in the assessment of mediastinal disease in NSCLC patients.

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.