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Colorectal cancer (CRC) remains a major concern with high morbidity and mortality worldwide. Despite the positive influence of chemotherapy on the decline in CRC mortality, the negative influence of chemotherapy-related adverse effects (CRAEs) caused by capecitabine (Cap) remains a challenging problem. DNA methylation alteration plays a pivotal role in gene expression regulation. Here, we aimed to screen reliable and novel biomarkers for CRC diagnosis and CRAE prediction using the advanced Illumina Infinium MethylationEPIC (850 K) BeadChip. Paired tumor and normal tissues from 21 Chinese CRC patients who received Cap-based adjuvant chemotherapy were analyzed. CRC-related methylation was characterized by hypermethylated promoter islands and hypomethylated intragenic openseas; CRAE-related methylation was characterized by hyper- (or hypo-) methylated intragenic (or intergenic) regions. Based on three types of methylation profiles (differentially methylated probes, differentially methylated regions, and gene-function-differentially methylated regions), pathway enrichment analyses revealed that CRC-related genes were significantly enriched in the neuronal system, metabolism of RNA, and extracellular matrix organization; CRAE-related genes were abundantly enriched in pathways controlling regeneration functions and immune response. Finally, based on genes within the mostly related pathways and LASSO logistic regression selection, the integrated-methylation-marker systems developed here demonstrated high discriminative accuracy in both CRC diagnosis (AUROC = 1) and CRAE prediction (AUROC = 0.817–1). In conclusion, we conducted a comprehensive DNA methylation analysis of CRC patients with chemotherapy, which provided new insights into the formation of CRC and CRAEs. Most importantly, our findings identified potentially CRAE-related metabolic pathways and markers, providing a valuable reference for personalized medicine promising better safety. Trail registration: ClinicalTrials.gov , NCT03030508 , Registered 25 January 2017, https://www.clinicaltrials.gov/ct2/show/NCT03030508?term=NCT03030508&draw=2&rank=1 .

Recent studies have demonstrated the superiority of non-orthogonal multiple access (NOMA) over orthogonal multiple access (OMA) in cooperative communication networks. In this paper, we propose a novel half-duplex cooperative asynchronous NOMA (C-ANOMA) framework with user relaying, where a timing mismatch is intentionally added in the broadcast signal. We derive the expressions for the individual throughputs of the strong user (acts as relay) which employs the block-wise successive interference cancellation (SIC) and the weak user which combines the symbol-asynchronous signal with the interference-free signal. We analytically prove that in the C-ANOMA systems with a sufficiently large frame length, the strong user attains the same throughput to decode its own message while both users can achieve a higher throughput to decode the weak user's message compared with those in the cooperative NOMA (C-NOMA) systems. Besides, we obtain the optimal timing mismatch when the frame length goes to infinity. Furthermore, to exploit the trade-off between the power consumption of base station and that of the relay user, we solve a weighted sum power minimization problem under quality of services (QoS) constraints. Numerical results show that the C-ANOMA system can consume less power compared with the C-NOMA system to satisfy the same QoS requirements.

Background X-linked agammaglobulinemia (XLA) is a primary immunodeficiency disorder caused by germline mutations in the Bruton tyrosine kinase (BTK) gene on X chromosome. These mutations disturb B-cell development, decrease immunoglobulin levels, increase susceptibility to infection or neoplasms, and increase the risk of developing colorectal cancer (CRC). For occasional cases of CRC have been reported in XLA patients, low levels of B lymphocytes and immunoglobulins induced by congenital immune disorder make them more susceptible to drug-related toxicities (DRT). Therefore, gene sequencing, therapeutic drug monitoring and any possible measurement to predict DRT should be considered before determining the course of chemotherapy for XLA patients with CRC. Case presentation In this study, we reported a 21-year-old male who developed metastatic CRC in the context of XLA. Since the whole exome sequencing and therapeutic drug monitoring did not reveal any predictive markers of DRT, we applied standard first-line chemotherapy to the patient. However, progressive disease occurred after the fifth treatment cycle. Therefore, the administration of oxaliplatin was changed to irinotecan as second-line therapy. After that, the patient firstly suffered from severe hypocalcemia and eventually died due to metastatic CRC after the eighth treatment cycle. The overall survival time was 7.5 months. Conclusions This study reported the first written record of a Chinese XLA patient with metastatic CRC and severe hypocalcemia. Whole exome sequencing and bioinformatic analysis indicated the somatic mutations in ABCA6, C6 and PAX3 genes might contribute to the early-onset and metastasis CRC. Besides, a number of germline mutations in genes related to calcium metabolism (CACNA2D4, CD36, etc.) and the administration of irinotecan were speculated to be the causes of severe hypocalcemia. We therefore suggested that in order to avoid severe DRT, clinicians should take genetic background and therapeutic drug monitoring into consideration while planning chemotherapy treatment for XLA patients with CRC.

Background: As cross-sectional images expanded in clinical practice, the number of renal lesions discovered incidentally has been increasing. CT protocols for renal mass evaluation may include pre- and post-contrast phase. However, a major concern with respect to those multiphase techniques is often the radiation dose. One further critical issue is how to minimize the radiation dose while image quality is optimized in routine daily clinical practice. Objectives: To evaluate the image quality and radiation dose of renal artery CT angiography (CTA) with optimal sinogram affirmed iterative reconstruction (SAFIRE) strength level at 80 kVp for optimizing the scan and reconstruction parameters of renal artery CTA, in comparison to 120 kVp acquisition with filtered back projection (FBP). Patients and Methods: Sixty consecutive patients were classified into three groups prospectively in this study: 1) 80 kVp group (n = 30) with FBP and 2) 80 kVp group with SAFIRE (S4) and 3) 120 kV group (n = 30) with FBP. CT values and noise were measured, contrast-to-noise ratio (CNR) and signal-to-noise ratio (SNR) of the renal artery CTA were calculated for quantitative assessment. Subjective image quality was evaluated by two experienced abdominal radiologists with a five-point scale in a blinded and randomized setting for qualitative assessment. Volume CT dose index (CTDIvol) and size-specific dose estimate (SSDE) were calculated and estimated for each subject presented in this study. Results: As for quantitative assessment, CNR, SNR and CT values of renal artery in 80kVp group with SAFIRE strength levels or FBP were higher than those of 120 kVp group with FBP (all Ps < 0.05), the mean noise gradually decreased in 80kVp group when increasing the SAFIRE strength levels (S1 - S5). As for qualitative assessment, the overall image quality, vessel sharpness, segmental renal artery displayed in maximum intensity projection (MIP) or multiplanar reformation (MPR), and diagnostic confidence of the two groups were all accepted by two radiologists (inter-observer agreement ranged from 0.600 to 0.940) (score ≥ 3). The overall image quality of 80 kVp with SAFIRE 4 was similar to that of 120 kVp group with FBP (P = 0.412), as well as segmental renal artery displayed in MIP and diagnostic confidence (P = 0.095 and P = 0.061, respectively). As for radiation dose reduction, 80kVp group could reduce 32.7% CTDIvol and 31.2% SSDE compared to the 120 kVp group. Conclusion: In patients with BMI lower than 28 kg/m2, renal artery CTA at 80 kVp with SAFIRE is feasible and can provide satisfactory images for clinical applications. This method also provides reduction in radiation dose. SAFIRE strength level 4 is recommended for reconstructing renal artery CTA.

The base station (BS) density influences the coverage performance of cellular communication system. In massive multiple input multiple output (MIMO) system, each BS is equipped with large scale antenna array. The stochastic geometric model is employed because of its analytical tractability. This paper demonstrates that BS density has to be below a certain bound in order to satisfy the coverage requirement in massive MIMO system. Closed-form expression for the BS density bounded by maximum outage probability is derived using Lambert W function. Moreover, the expression for the upper bound of successful area spectral efficiency (ASE) is also derived. Our study claims that increasing BS density will lead to the deterioration of coverage performance in massive MIMO system.

Beamforming (BF) is an effective method to restrain interference in cellular communication systems. Steering beam direction in 3D space can improve useful signal power that user equipments (UEs) received and eliminate interference effectively. In this paper, we focus on how to choose 3D-BF angles of beam and propose a cooperative angle selecting scheme based on maximum signal to leakage plus noise ratio (SLNR) (CAS-MSLNR) to increase sum throughput of Heterogeneous Network (HetNet). In the proposed scheme, 3D-BF angles of every node in the same group node (GN) are chosen preliminarily by centralized coordination method to restrain intra-GN interference. Then, in each GN, the macro cell base station (MBS) adjusts the 3D-BF angles to maximize SLNR. Simulation result demonstrates that CAS-MSLNR 3D-BF outperforms 2D-BF and UE-specific 3D-BF in terms of sum throughput and cell-edge throughput.

The purpose of this study was to investigate the changes in the cerebral blood flow (CBF) and spectrum variables in the posterior cingulate region of patients with AD under the detection of arterial spin labeling (ASL) and magnetic resonance spectroscopy (MRS). A total of 20 AD patients (8 males and 12 females; mean age, 64.84±8.82 years) and 20 healthy controls (9 males and 11 females; mean age, 64.94±7.93 years) were included in this study for analysis. All images were obtained using a 3.0-T MR imager and an 8-channel head array receiving coil. MRS measurements were conducted exploring variables of metabolite ratios. Statistical analyses were conducted with the SPSS 11.0 statistical software package. Findings in the present study revealed a significant difference in the mean MMSE scores between the AD group and the healthy control group (16.21±4.01 vs. 27.35±1.01, P

Energy efficiency and spectral efficiency are two important aspects of wireless system. In this paper, a distributed scheme of energy-efficient power control is addressed jointly with 3D-beamforming (3D-BF), named as energy-efficient 3D-beamforming (EE-3DBF). In consideration of the high complexity to deal with power control and 3D-BF simultaneously, EE-3DBF is divided into limited coordination downtilt constraint 3D-BF (LCDC-3DBF) and energy-efficient power control (EEPC). LCDC-3DBF is applied to add downtilt constrain to restrain inter-cell inter-ference in cell edge. EEPC is employed to choose transmit power for each base station (BS) to gain energy efficiency. Simulation result demonstrates that EE-3DBF improves both energy efficiency and the throughput of system.

This paper proposes a trajectory-based optimal area forwarding (TOAF) algorithm tailored for multihop data delivery from infrastructure nodes (e.g., Internet access points) to moving vehicles (infrastructure-to-vehicle) in vehicular ad hoc networks (VANETs) with partial deployment of stationary nodes. It focuses on reducing the delivery-delay jitter and improving the low reliability of infrastructure-to-vehicle communication. To adapt with the real world, TOAF supposes that stationary nodes are partially installed at intersections in VANETs, and nodes' trajectories can be calculated and predicted, such as using cloud services and GPS, to find the optimal area where the destination vehicle may receive a packet timely. AP selects the optimal area from the trajectory of the destination vehicle and determines the delivery sequence, which includes stationary and mobile nodes from the AP to the optimal area. During delivery, if a new node finds that the delay to the next stationary node is less than that of the current carrier, it can be added to the sequence, reducing the delivery delay. The addition of a new node continues until the packet reaches the optimal area and infrastructure-to-vehicle communication is achieved. The simulation results confirm that TOAF can improve the performance of delivery-delay jitters and reliability of infrastructure-to-vehicle communication with partial deployment of stationary nodes.