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Abstract Objective MicroRNAs, as essential players in tumorigenesis, have been demonstrated to have a revolutionary effect on human cancer research. Ovarian cancer is the primary reason of death among gynecologic malignancies. In view of this, it is significant to identify prognostic and predictive markers for treatment of ovarian cancer. The aim of this study was to probe into the effects of miR‐378a‐3p and protein disulfide‐isomerase A4 (PDIA4) on the biological functions of ovarian cancer cells. Methods miR‐378a‐3p expression and PDIA4 messenger RNA expression in human ovarian cancer cells, normal human ovarian epithelial cells, and serum of both ovarian cancer patients and healthy people were detected by reverse transcription‐quantitative polymerase chain reaction, and the PDIA4 protein expression was tested by Western blot analysis. Ovarian cancer OVCAR3 and SKOV3 cells were transfected or cotransfected with miR‐378a‐3p mimic or pcDNA3.1‐PDIA4 or their negative control plasmids to explore their roles in biological functions in ovarian cancer cells. Luciferase activity and RIPA assays were implemented to validate the interaction between miR‐378a‐3p and PDIA4. Western blot analysis was utilized to detect phosphatidylinositol‐3 kinase/serine/threonine kinase (PI3K/AKT) signaling pathway‐related protein expression and their phosphate expression levels. Results miR‐378a‐3p was elevated and PDIA4 was decreased in ovarian cancer cells and serum. In addition, miR‐378a‐3p mimic induced ovarian cancer cell growth, while miR‐378a‐3p inhibitor and pcDNA3.1‐PDIA4 presented an inverse trend. pcDNA3.1‐PDIA4 partially eliminated the capabilities of miR‐378a‐3p mimic on ovarian cancer progression. Meanwhile, miR‐378a‐3p was found to negatively regulate PDIA4, and miR‐378a‐3p mimic increased the phosphorylation levels of AKT and PI3K, while pcDNA3.1‐PDIA4 exhibited an opposite tendency. Furthermore, pcDNA3.1‐PDIA4 largely eliminated the functions of miR‐378a‐3p mimic on phosphorylation levels of AKT and PI3K. Conclusion This study provides evidences that miR‐378a‐3p activates PI3K/AKT signaling pathway by modulating PDIA4 expression, thereby playing a role in promoting the growth of ovarian cancer cells. This study provides novel directions for targeted therapy of ovarian cancer.

We consider use of fixed broadband wireless networks to provide packet services for telecommuting and Internet access. Each cell in such networks is divided into multiple sectors, each of them served by a sector antenna colocated with the base station (BS), and user terminals also use directional antennas mounted on the rooftops of homes or small offices and pointed to their respective BS antennas. To support a target data rate of 10 Mb/s, a bandwidth of several MHz is required. Since radio spectrum is expensive, the bandwidth needs to be reused very aggressively. Thus, efficient strategies for frequency reuse and managing cochannel interference are critically important. We propose here several algorithms for dynamic radio-resource allocation in the fixed wireless networks. in particular, a method to be referred to as the staggered resource allocation (SRA) method uses a distributed scheduling algorithm to avoid major sources of interference while allowing concurrent packet transmission and meeting signal-to-interference objective. The performance of the method is studied by analytic approximations and detailed simulation. Our results show that the combination of directional antennas plus the SRA method is highly effective in controlling cochannel interference. For reasonable system parameters, the SRA method delivers a throughput in excess of 30% per sector while permitting a given frequency band to be reused in every sector of every cell. It also provides satisfactory probability of successful packet transmission. in addition, a simple control mechanism can be applied in the method to improve performance for harsh radio environments. Index Term - Broadband communication, communication system performance, communication systems, electromagnetic radiative interference, interference, packet radio, protocols, radio communication, radio spectrum management, time-division multiplexing

This paper presents a unified performance model for the integrated voice/data wireless system using reservation-type multiple-access (MA) schemes. It is observed that although these schemes are different in the frame structure and resource assignment procedure, all of them can be described by several common state variables whose evolvement exhibits the Markovian property. based on this observation, a general Markovian model is developed in this paper. Three performance measures, namely, voice-packet-loss probability, data throughput, and data delay are defined. As a special case, the performance evaluation model for the voice-only system is also presented. Numerical results are given and verified by simulation under both voice-only and integrated scenarios using packet-reservation MA (PRMA), dynamic time-division multiple access (D-TDMA), and resource-auction multiple access (RAMA) as examples. It is found that our analytical model is quite accurate, especially in the region of interest. The impact of system parameters (such as the voice-permission probability, data-retransmission probability, maximum number of voice slots per frame, etc.) on the integrated system performance is also investigated for these three example systems. Index Terms - Markovian models, multiple access, reservation-based protocols, TDMA.

In this paper, a new Markovian model is developed to analyze the Packet Reservation Multiple Access (PRMA) protocol over Rician fading channels with lognormal shadowing. The packet dropping probability and the voice user capacity are defined as the performance measures. A new formula is derived to evaluate the dropping probability in the fading environment. The analytical results from our new formula show close agreement with those from computer simulations. The capture effect on the PRMA system performance is also studied. We found that, with capture, the user capacity will be improved and the service quality will degrade gracefully when the number of active users in the system increases. Using the dropping probability as the criterion, we also determine the optimal permission probability in a microcellular environment.

Adaptive modulation techniques have the potential to substantially increase the spectrum efficiency and to provide different levels of service to users, both of which are considered important for third-generation cellular systems. In this work, we propose a general framework to quantify the potential gains of such techniques. Specifically, we study the throughput performance gain that may be achieved by combining adaptive modulation and power control. Our results show that: 1) using adaptive modulation even without any power control provides a significant throughput advantage over using signal-to-interference-plus-noise ratio (SINR) balancing power control and 2) combining adaptive modulation and a suitable power control scheme leads to a significantly higher throughput as compared to no power control or using SINR-balancing power control. The first observation is especially important from an implementation point of view. Adjusting the modulation level without changing the transmission power requires far fewer measurements and feedback as compared to the SINR-balancing power control or the optimal power control. Hence, it is significantly easier to implement. Although presented in the context of adaptive modulation, the results also apply to other variable rate transmission techniques, e.g., rate adaptive coding schemes, coded modulation schemes, etc. This work provides valuable insight into the performance of variable rate transmission techniques in multi-user environments. Index Terms - Adaptive modulation, cellular system, power control, variable rate transmission.

Proposes a framework for network-assisted radio resource management in wireless data networks. Presentation of the proposed framework and two representative algorithms; Analysis of the performance of proposed network-assisted resource allocation algorithms; Comparison with other dynamic channel assignment algorithms.

Hepatocellular carcinoma (HCC) is a leading cause of cancer-related mortality worldwide. Interferon-alpha (IFN-α) has recently been recognized to harbor therapeutic potential in prevention and treatment of HCC. IFN-stimulated gene 15 (ISG15) is an ubiquitin-like molecule that is strongly upregulated by type I interferons as a primary response to diverse microbial and cellular stress stimuli. Several studies have shown that the overexpression of ISG15 is correlated with multiply tumor types. However, the role of ISG15 in hepatitis B virus (HBV)-related HCC remains undetermined. ISG15 expression was found to be obviously higher in HBV-related HCC tissues than that in non-tumor tissues. ISG15 is a novel prognostic marker for predicting 5-year overall survival of HBV-related HCC patients. Overexpression of ISG15 was associated with clinicopathological characteristics and poor patient outcomes. ISG15 may serve as a novel prognostic marker for HBV-related HCC. Therefore, ISG15 may represent a novel HCC marker with prognostic significance and may be helpful in selecting patients for and predicting response to the treatment of HBV-related HCC.

Objective: The objective of the present study was to explore the major risk factors of surgical complications using the Clavien-Dindo classification., Methods: The case-control design was used. A total of 1049 patients who underwent radical gastrectomy in Hunan Cancer Hospital between October 2010 and August 2014 were retrospectively analyzed, including 122 patients (11.6%) with complications and 927 patients (88.4%) with no complications. Risk factors were evaluated., Results: Following radical gastrectomy, 122 patients (11.6%) experienced a total of 151 complications. The incidence of Stages II, IIIa, IIIb, IVa, IVb and V complications was 9.6% (n = 101), 2.5% (n = 26), 1.0% (n = 11), 0.8% (n = 8), 0% (n = 0), and 0.5% (n = 5), respectively. The incidence of severe complications (Stage ≥ IIIa) was 4.8% (n = 50). Multivariate analysis showed that combined resection (Odds Ratio [OR] = 3.36, 95% confidence interval [CI]: 1.71~6.60, P < 0.01), perioperative blood transfusion (OR = 2.13, 95% CI: 1.38-3.29, P < 0.01), and BMI ≥ 25 kg/m(2) (OR = 1.98, 95% CI: 1.16-3.40, P = 0.01) were independent risk factors of complications., Conclusions: Combined resection, perioperative blood transfusion, and BMI ≥ 25 kg/m(2) are positively correlated with complications.

Objective: To explore the major risk factors for pulmonary infection after radical gastrectomy in patients with gastric cancer., Methods: From November 2010 to February 2014, a total of 765 patients undergoing radical gastrectomy at our hospital were divided into 2 groups based upon the presence of postoperative pulmonary infection (n = 32, 4.2%) or not (n = 733, 95.8%). Their clinicopathological data were retrospectively analyzed by Logistic regressive analysis with a case-control study model., Results: Comparing with the control group, the patients had longer surgical duration (245.7 ± 66.7 vs 210.9 ± 47.2 min, P < 0.01), higher rates of requiring intensive care (12.50% vs 2.86%, P = 0.02) and longer post-operative hospital stays (21.9 ± 24.9 vs 14.2 ± 4.2 days, P < 0.01) in the postoperative pulmonary infection group.Univariate Logistic regressive analysis found that age ≥ 60 years, smoking ≥ 400 year by cigarette, diabetes mellitus, chronic obstructive pulmonary disease, proximal or total gastrectomy, combined organ resection, surgical duration ≥ 240 min, intra-operative blood loss ≥ 300 ml, peri-operative transfusion, transfusion ≥ 3 unit packed red blood cell, post-operative transfusion and post-operative complications other than pulmonary infections were associated with postoperative pulmonary infection (all P < 0.05).Further multivariate analysis identified 4 independent risk factors for pulmonary infection after radical gastrectomy, including diabetes mellitus (OR = 4.77, 95%CI:1.18-19.23), post-operative complications other than pulmonary infections (OR = 3.15, 95%CI:1.25-7.90), intra-operative blood loss ≥ 300 ml (OR = 2.63, 95%CI:1.17-5.90) and post-operative nasogastric tube ≥ 5 days (OR = 2.30, 95%CI:1.02-5.21)., Conclusion: Correcting the modifiable risk factors may reduce the incidence of pulmonary infection and shorten the length of hospital stays and costs after radical gastrectomy in patients with gastric cancer.

Objective: To explore the association of perioperative homologous blood transfusion (packed red blood cell, PRBC) and postoperative complications after radical gastrectomy in patients with gastric cancer., Methods: From October 2010 to July 2013, a total of 636 patients undergoing radical gastrectomy at Department of Gastric, Duodenal & Pancreatic Surgery at Hunan Provincial Tumor Hospital were divided into 2 groups according to perioperative blood transfusion (n = 170, 26.73%) or not (n = 466, 73.27%). Their clinicopathological data, such as age, gender, co-morbidities, surgical duration, intraoperative blood loss volume and pathological stage were retrospectively analyzed by case-control study model. And the transfusion group was further divided into subgroup by transfusion volume (total PRBC<3.0, 3.0-7.5 or >7.5 U) and timing (pre-, intra- or post-operative) to examine the association of transfusion volume and timing with postoperative complications by Logistic regression., Results: Thirty-two patients suffered from complications in the transfusion group (18.82%). And it was significantly more common than that in the control group (10.09% (47/466) , P < 0.01). Moreover, the complication rate (33.33% (12/36) ) was obviously higher in the large transfusion volume group (PRBC>7.5 U) than with those in the moderate (15.53% (16/103), P = 0.02) and low groups (12.90% (4/31) , P = 0.04). Infection was more common along with the total amount of transfused blood (6.45% (2/31), 10.68% (11/103) and 19.44% (7/36) in the low, moderate and large transfusion group respectively). Yet the differences were insignificant (P = 0.22). There was no significant difference of complication rates among the pre-, intra- and post-operative transfusion group classified by transfusion time (P = 0.39). And the postoperative infection rates were also insignificantly different (P = 0.88). Further Logistic analysis revealed that perioperative transfusion (OR = 2.71, 95% CI: 1.40-5.27, P < 0.01) was an independent risk factor for postoperative complications after radical gastrectomy., Conclusions: Perioperative blood transfusion is significantly associated with postoperative complications after radical gastrectomy in patients with gastric cancer. And a positive correlation exists between infection and the amount of transfused blood. But there was no association between transfusion time and complications. Thus decreasing perioperative transfusion may reduce the incidence of postoperative complications and shorten the length of hospital stays.