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Due to the limited computation resources of mobile devices in cognitive radio networks, the secondary users in the network can suffer from long executing time, which is not acceptable for latency‐sensitive and computation‐intensive tasks. To tackle this issue, this paper proposes to reduce the task computing latency for secondary networks by offloading the tasks to edge servers through leveraging mobile edge computing (MEC) that is emerging as a promising technology to augment the computation capacity of mobile devices. Specifically, under the conditions that the interference caused by secondary users is tolerable to primary user and within the available computation resources of the MEC server, the primary user and secondary users both can offload tasks to the MEC server through nonorthogonal multiple access. Thus, we jointly formulate the offloading decision and power control as an optimization problem, aiming at minimizing the overall computing latency for secondary networks. To overcome the computational complexity caused by the nonconvexity of the original problem, we transform the original problem to a solvable problem and decouple the transformed problem into the separate offloading decision and power control. An iterative algorithm is proposed based on block coordinate decent method to achieve the near‐optimal solution. Simulation results show that under the same parameters, such as the number of primary users, maximum transmit power, computational capability of the MEC server and the computational capability of the secondary users, the proposed NOMA‐enabled computation offloading scheme can effectively reduce the overall computing latency for the secondary network and improve the percentage of offloading secondary users than those of OMA‐enabled. [ABSTRACT FROM AUTHOR]

Purpose: Chronic inflammation and lipid peroxidation (LPO) are associated with the pathogenesis of hepatocellular carcinoma (HCC), and γ-hydroxy-1, N 2 -propanodeoxyguanosine (γ-OHPdG) is a promutagenic DNA adduct derived from LPO. This study aimed to examine the relationship between γ-OHPdG and the progression of liver carcinogenesis., Methods: Primary HCC specimens were obtained from 228 patients and cirrhosis specimens from 46 patients. The patients were followed up with after surgery via outpatient visits and telephone calls. The levels of γ-OHPdG were determined by immunohistochemical analysis in the carcinomatous tissues together with adjacent and cirrhosis tissues., Results: γ-OHPdG levels in the cancerous tissues were significantly higher compared to adjacent tissues (P < 0.001) and also higher than the ones from the tissues of cirrhosis patients. Along with tumor size, histological grade, MVI grade, T stage, the percentage of ki67-positive cells and HCC progression, γ-OHPdG levels in cancerous tissues showed a gradually increasing trend. Moreover, prognostic analysis showed that higher γ-OHPdG levels in cancerous tissues were strongly correlated with lower overall survival (P < 0.001), lower intrahepatic recurrence-free survival (P < 0.001) and lower distant metastasis-free survival (P < 0.05). There was a trend, although not statistically significant, of increased levels of γ-OHPdG in cirrhosis cases that advanced to HCC, whereas γ-OHPdG levels reversely correlated with the period of time observed for cirrhosis advanced to HCC., Conclusions: These results suggest that γ-OHPdG is a prognostic biomarker for predicting outcomes in HCC, and may serve as a prospective indicator for predicting HCC in cirrhosis patients.

Primary hepatic pregnancy is an extremely rare event which is difficult to diagnose due to its unusual location; moreover the potential mortality rate is five to seven times higher than the rate found in other ectopic pregnancies. We report a case of primary hepatic pregnancy in a 23-year-old woman, who presented with a history of one cesarean section and had taken oral contraceptives within half a year prior to her presentation. Interestingly this patient has no history of amenorrhoea, and no clinical symptoms of chills, fever, nausea, vomiting and diarrhea. Imaging findings showed an abnormal mass on the lower part of the right lobe. The patient was misdiagnosed with a liver tumor prior to operation. Histopathologic examination found that chorionic villi with trophoblasts infiltrated the hepatic tissue. A few trophoblasts were detected in some hepatic veins. HCG immunostaining showed positive reactivity in the trophoblasts. We believe that some risk factors of primary hepatic pregnancy such as the history of cesarean section and oral contraceptive should be taken into serious consideration and raise the index of suspicion, especially in the women of reproductive age, with or without a history of amenorrhoea. Timely diagnosis should be made in order to avoid mortality from rupture of the gestational sac., Competing Interests: None., (IJCEP Copyright © 2019.)

Solid pseudopapillary neoplasm occurring as a primary tumor outside the pancreas is a rare event. We report a case of an ovarian primary occurring with an ill-defined cystic mass in a 39-year-old woman. The morphologic and immunohistochemical features of the ovarian neoplasm described in this report are compatible with those of solid pseudopapillary neoplasm of the pancreas. Histologically, the tumor cells of the case we report infiltrate into the ovarian parenchyma. Because of the diagnosis is not clear before surgery, the patient had a reoccurrence two months after the operation in which laparoscopic simple ovarian cystectomy and part ovarian tissue removal, followed by the right salpingo-oophorectomy. The case herein confirms that solid pseudopapillary neoplasm of the ovary belongs to the class of low-grade malignant tumor with certain invasiveness. The diagnosis should be taken into serious consideration in order to avoid missed diagnosis and delay treatment. Through this case we have a better understanding of the biological behavior of solid pseudopapillary neoplasm of the ovary.