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Background Colon cancer is one of the most common malignancies worldwide, and chemotherapy is a widely used strategy in colon cancer clinical therapy. However, chemotherapy resistance is a major cause of disease recurrence and progression in colon cancer, and thus novel drugs for treatment are urgently needed. Tetramethylpyrazine (TMP), a component of the traditional Chinese medicine Chuanxiong Hort, has been proven to exhibit a beneficial effect in tumors. Aim To investigate the potential anticancer activity of TMP in colon cancer and its underlying mechanisms. Methods Colon cancer cells were incubated with different concentrations of TMP. Cell viability was evaluated by crystal violet staining assay and cell counting kit-8 assay, and cell apoptosis and cell cycle were assessed by flow cytometry. Results TMP significantly inhibited the proliferation of colon cancer cells in a dose- and time-dependent manner. In addition, flow cytometry revealed that TMP induced cell cycle arrest at the G0/G1 phase. TMP treatment caused early stage apoptosis in SW480 cells, whereas it caused late stage apoptosis in HCT116 cells. Conclusion Our studies demonstrated that TMP inhibits the proliferation of colon cancer cells in a dose- and time-dependent manner by inducing apoptosis and arresting the cell cycle at the G0/G1 phase. Our findings suggest that TMP might serve as a potential novel therapeutic drug in the treatment of human colon cancer.

In the study of chemical graph theory, an enormous number of research analyses have confirmed that the characteristics of chemicals have a nearby connection with their atomic structure. Topological indices were the critical tools for the analysis of these chemical substances to consider the essential topology of chemical structures. Topological descriptors are the significant numerical quantities or invariant in the fields of chemical graph theory. In this study, we have studied the crystal structure of copper oxide ( Cu 2 O {{\rm{Cu}}}_{2}{\rm{O}} ) chemical graph, and further, we have calculated the ev-degree- and ve-degree-based topological indices of copper oxide chemical graph. This kind of study may be useful for understanding the atomic mechanisms of corrosion and stress–corrosion cracking of copper.

BACKGROUND Recent evidence showed that combining endoscopic submucosal dissection (ESD) and laparoscopic sentinel lymph node dissection may avoid unnecessary gastrectomy in treating early mucinous gastric cancer (EMGC) patients with risks of positive lymph node metastasis (pLNM). AIM To explore the predictive factors for pLNM in EMGC, and to optimize the clinical application of combing ESD and sentinel lymph node dissection in a proper subgroup of patients with EMGC. METHODS Thirty-one patients with EMGC who had undergone gastrectomy with lymph node dissection were consecutively enrolled from January 1988 to December 2016. Univariate and multivariate logistic regression analyses were used to estimate the association between the rates of pLNM and clinicopathological factors, providing odds ratio (OR) with 95% confidence interval. And the association between the number of predictors and the pLNM rate was also investigated. RESULTS Depth of invasion (OR = 7.342, 1.127-33.256, P = 0.039), tumor diameter (OR = 9.158, 1.348-29.133, P = 0.044), and lymphatic vessel involvement (OR = 27.749, 1.821-33.143, P = 0.019) turned out to be significant and might be the independent risk factors for predicating pLNM in the multivariate analysis. For patients with 1, 2, and 3 risk factors, the pLNM rates were 9.1%, 33.3%, and 75.0%, respectively. pLNM was not detected in seven patients without any of these risk factors. CONCLUSION ESD might serve as a safe and sufficient treatment for intramucosal EMGC if tumor size ≤ 2 cm, and when lymphatic vessel involvement is absent by postoperative histological examination. Combining ESD and sentinel lymph node dissection could be recommended as a safe and effective treatment for EMGC patients with a potential risk of pLNM.

The aim of the present study was to evaluate the microcirculation perfusion in patients with acute radiation-induced liver damage (RILD) and explore the feasibility of non-invasive evaluation of RILD using quantitative analysis of contrast-enhanced ultrasound (CEUS). Patients who successfully underwent three-dimensional conformal intensity-modulated radiotherapy for abdominal tumors were selected. CEUS was performed on the liver prior to and 2, 3 and 4 weeks after exposure, and the time-intensity curve (TIC) was obtained by quantitative analysis of CEUS. The time to peak (TTP), gradient (Grad) and area under the curve (AUC) were analyzed offline. The Grad of the CEUS TIC was decreased and TTP increased with the prolongation of the irradiation duration, with statistically significant differences between the values in the 2-, 3- and 4-week groups vs. those prior to exposure (P

In statistical analysis, oftentimes a probability density function is used to describe the relationship between certain unknown parameters and measurements taken to learn about them. As soon as there is more than enough data collected to determine a unique solution for the parameters, an estimation technique needs to be applied such as “fractional calculus”, for instance, which turns out to be optimal under a wide range of criteria. In this context, we aim to present some novel estimates based on the expectation and variance of a continuous random variable by employing generalized Riemann-Liouville fractional integral operators. Besides, we obtain a two-parameter extension of generalized Riemann-Liouville fractional integral inequalities, and provide several modifications in the Riemann-Liouville and classical sense. Our ideas and obtained results my stimulate further research in statistical analysis.

First published online: 13 October 2020 We develop a new robust control scheme for a non-holonomic spherical robot. To this end, the mathematical model of a pendulum driven non-holonomic spherical robot is first presented. Then, a recurrent neural network-based robust nonsingular sliding mode control is proposed for stabilization and tracking control of the system. The designed recurrent neural network is applied to approximate compound disturbances, including external interferences and dynamic uncertainties. Moreover, the controller is designed in a way that avoids the singularity problem in the system. Another advantage of the proposed scheme is its ability for tracking control while there exists control input saturation, which is a serious concern in robotic systems. Based on the Lyapunov theorem, the stability of the closed-loop system has also been confirmed. Lastly, the performance of the proposed control technique for the uncertain system in the presence of an external disturbance, unknown input saturation, and dynamic uncertainties has been investigated. Also, the proposed controller has been compared with a Fuzzy-PID one. Simulation results show the effectiveness and superiority of the developed control technique.

In the present study, a vertically oriented rectangular-shaped enclosure with triangular shaped double fins filled with PCM was considered as a Latent Thermal Energy Storage (LTES) system. Nine different cases including one pure PCM, three nano-PCM (having different volume fractions), two porous-PCM (having different porosity values) and three nano/porous PCM were considered to conduct the investigation. The PCM material employed for investigations was lauric acid. The copper made porous media was assumed to have porosity values of 98% and 95%. The Al 2 O 3 nano-particles with the volume fractions of 1%, 2% and 4% combined with Lauric acid were considered as nano-PCM. The results presented that the cases with nanoparticles volume fractions of 1% and 2% could improve the melting performance. However, the case with nanoparticle volume fraction of 4% deteriorated the melting performance. In the cases with individual usage of nano-PCM the best case was related to the case with the volume fraction of 1% and resulted in about 184s time-saving. It was found that individual usage of porous media could significantly improve the melting performance; however, adding nanoparticles to the cases with porous media, regardless of volume fraction of nanoparticles deteriorates the melting performance of PCM enclosure.

The human immunodeficiency virus (HIV), as one of the most hazardous viruses, causes destructive effects on the human bodies’ immune system. Hence, an immense body of research has focused on developing antiretroviral therapies for HIV infection. In the current study, we propose a new control technique for a fractional-order HIV infection model. Firstly, a fractional model of the HIV model is investigated, and the importance of the fractional-order derivative in the modeling of the system is shown. Afterward, a type-2 fuzzy logic controller is proposed for antiretroviral therapy of HIV infection. The developed control scheme consists of two individual controllers and an aggregator. The optimal aggregator modifies the output of each individual controller. Simulations for two different strategies are conducted. In the first strategy, only reverse transcriptase inhibitor (RTI) is used, and the superiority of the proposed controller over a conventional fuzzy controller is demonstrated. Lastly, in the second strategy, both RTI and protease inhibitors (PI) are used simultaneously. In this case, an optimal type-2 fuzzy aggregator is also proposed to modify the output of the individual controllers based on optimal rules. Simulations results demonstrate the appropriate performance of the designed control scheme for the uncertain system.

// Hua Li 1, * , Shubo Chen 2, * , Hui Li 3, * , Jianxin Cui 4, * , Yunhe Gao 4 , Dianchao Wu 1 , Shangfeng Luan 1 , Yan Qin 1 , Tongshan Zhai 1 , Dengxiang Liu 5 and Zhibin Huo 1 1 Department of Surgical Oncology, Affiliated Xing Tai People Hospital of Hebei Medial University, Xingtai 054001, China 2 Department of Surgical Urology, Affiliated Xing Tai People Hospital of Hebei Medial University, Xingtai 054001, China 3 Department of General Surgery, Affiliated Xing Tai People Hospital of Hebei Medial University, Xingtai 054001, China 4 Department of General Surgery, Chinese People’s Liberation Army General Hospital, Beijing 100853, China 5 Institute of Cancer Control, Affiliated Xing Tai People Hospital of Hebei Medial University, Xingtai 054001, China * These authors have contributed equally to this work Correspondence to: Zhibin Huo, email: huozhibinxt@126.com Dengxiang Liu, email: rmyy666@163.com Keywords: PIK3CA; gastric cancer; prognosis; alteration; meta-analysis Received: August 09, 2017 Accepted: December 26, 2017 Published: January 02, 2018 ABSTRACT Background: Increasing evidence suggests that dysregulation of phosphatidylinositol-4, 5-bisphosphate 3-kinase, catalytic subunit alpha (PIK3CA) plays an important role in carcinogenesis. However, the relationship between PIK3CA expression and gastric cancer (GC) prognosis remains controversial. Methods: We searchedPubMed, Embase, Web of Science, and the Cochrane Library databases for relevant studies up to June 30, 2017. Primary outcomes were hazard ratio (HR), odds ratio (OR), and 95% confidence intervals (CI) for association with overall survival and clinicopathological features. Results: Eleven studies comprising 2481 GC patients were analyzed. Pooled analysis showed that PIK3CA upregulation was significantly associated with worse overall survival (HR = 1.79, 95% CI 1.42–2.27, p < 0.001) at the protein (HR = 1.94, 95% CI 1.52–2.47, p < 0.001) but not the gene (HR = 1.57, 95% CI 0.92–2.69, p = 0.097) level. PIK3CA gene mutation did not correlate with overall survival (HR = 1.05, 95% CI 0.83–1.34, p = 0.666) but was significantly associated with poor tumor differentiation (OR = 0.37, 95% CI 0.17–0.76, p = 0.011). Conclusion: High PIK3CA protein expression predicted poor prognosis in GC, whereas PIK3CA gene amplification or mutation did not. Moreover, PIK3CA mutation was an indicator of poorly differentiated tumors.

A novel approach to solve optimal control problems dealing simultaneously with fractional differential equations and time delay is proposed in this work. More precisely, a set of global radial basis functions are firstly used to approximate the states and control variables in the problem. Then, a collocation method is applied to convert the time-delay fractional optimal control problem to a nonlinear programming one. By solving the resulting challenge, the unknown coefficients of the original one will be finally obtained. In this way, the proposed strategy introduces a very tunable framework for direct trajectory optimization, according to the discretization procedure and the range of arbitrary nodes. The algorithm&rsquo, s performance has been analyzed for several non-trivial examples, and the obtained results have shown that this scheme is more accurate, robust, and efficient than most previous methods.

First published online: 30 September 2020 Modeling and analysis of financial systems have been interesting topics among researchers. The more precisely we know dynamic of systems, the better we can deal with them. This way, in this paper, we investigate the effect of market confidence on a financial system from the perspective of fractional calculus. Market confidence, which is a significant concern in economic systems, is considered, and its effects are comprehensively investigated. The system has been studied through numerical simulations and analyses, such as the Lyapunov exponents, bifurcation diagrams, and phase portrait. It is shown that the system enters chaos through experiencing a cascade of period doublings, and the existence of chaos is verified. Finally, an analog circuit of the chaotic system is designed and implemented to prove its feasibility in real-world applications. Also, through the circuit implementation, the effects of different factors on the behavior of the systems are investigated. (C) 2020 The Author(s). Published by Elsevier Ltd.

In this paper, a novel direct scheme to solve a set of time-delay fractional optimal control problems is introduced. The method firstly uses a set of Dickson polynomials as basis functions to approximate the states and control variables of the system. Next, the context of these basis functions and the use of a collocation method allow to transform the problem into a system of nonlinear algebraic equations. Finally, the unknown coefficients and control parameters in the original problem can be easily estimated by resolving the new system of equations. Given the high efficiency of the Dickson polynomials to deal with time-delay fractional systems, the proposed strategy involves a very tunable framework for direct trajectory optimization, according to the discretization procedure and the range of arbitrary nodes. The convergence analysis of the proposed method is presented, along with some illustrative examples which demonstrate its most relevant features.

The present paper aims to carry out a new scheme for solving a type of singularly perturbed boundary value problem with a second order delay differential equation. Getting through the solution, we used Reproducing Kernel Hilbert Space (RKHS) method as an efficient approach to obtain the analytical solution for ordinary or partial differential equations that appear in vast areas of science and engineering. A key of this method is to keeping the continuous form of problems. Indeed, without discretizing the continuous problem, we change it to an equivalent iterative form and proving its convergence. Also, we will present a construction of the reproducing kernel in Hilbert space that satisfying the homogeneous nonlinear boundary conditions of the considered problem. Accuracy amount of absolute error with respect to different parameters of singularity has been studied for the performance of this method by solving several hardly nonlinear problems. Error estimation and convergence analysis show that the approximate results have uniform convergence to the continuous solutions.

The aim of the present study was to examine and assess contrast-enhanced ultrasound in the early diagnosis of acute radiation-induced liver injury in a rat model. Sixty female rats were used, with 50 rats being utilized to produce an animal model of liver injury with a single dose of stereotactic X-ray irradiation of 20 Gy. Ten rats from the injury group and 2 rats from the control group were randomly selected on days 3, 7, 14, 21 and 28, and examined by contrast-enhanced ultrasound and histopathology of liver specimens. The rats were divided into four groups: the normal control group, mild, moderate, and severe radioactive liver injury groups based on the histopathological examination results. Hepatic artery arriving time (HAAT) and hepatic vein arriving time (HVAT) were recorded, and hepatic artery to vein transit time (HA-HVTT) was calculated. The time-intensity curve of liver parenchyma, the time to peak (TTP) and peak intensity (PI) were also obtained. Significant differences were observed between liver injury and control groups for PI and HA-HVTT (P

Rab family protein Rab5a has been implicated in cancer progression. To date, its expression pattern in human pancreatic cancer has not been investigated. This study aims to examine clinical significance, biological role, and potential mechanism of action of mRab5a in human pancreatic cancer. We analyzed Rab5a protein in cancer tissue of 111 cases of pancreatic cancer using immunohistochemistry. The results show that Rab5a overexpression correlates with high T stage, positive nodal status, and advanced TNM stage. We performed knockdown of Rab5a through transfection of Rab5a-specific siRNA in the Capan-2 cell line, which shows high endogenous expression, and of Rab5a plasmid in the CFPAC-1 cell line, which shows low endogenous expression. Rab5a knockdown inhibited cell proliferation and invasion while its overexpression promoted cell proliferation and invasion. In addition, overexpression of Rab5a induced resistance to 5-FU and gemcitabine while its knockdown reduced resistance to 5-FU and gemcitabine. Furthermore, our results show that Rab5a overexpression upregulates Wnt signaling and expression of Wnt target genes including c-myc and MMP7. Blocking Wnt signaling abolished the effects of Rab5a on Wnt targets and on cancer cell proliferation. In summary, our results show that Rab5a is overexpressed in pancreatic cancer and promotes aggressive biological behavior through regulation of the Wnt/β-catenin signaling pathway.

The aim of this study was to identify clinicopathological factors predictive of lymph node metastasis (LNM) in intramucosal poorly differentiated early gastric cancer (EGC), and further to expand the possibility of using laparoscopic surgery for the treatment of intramucosal poorly differentiated EGC. Data from 65 patients with intramucosal poorly differentiated EGC and surgically treated were collected, and the association between the clinicopathological factors and the presence of LNM was retrospectively analyzed by univariate and multivariate logistic regression analyses. Univariate analysis showed that number of tumors, tumor size and lymphatic vessel involvement (LVI) were the significant and independent risk factors for LNM (all P < 0.05). The LNM rates were 5.0%, 18.2% and 66.7%, respectively. There was no LNM in 31 patients without the three risk clinicopathological factors The number of tumors, tumor size, and LVI are independently associated with the presence of LNM in intramucosal poorly differentiated EGC. Thus, these three risk factors may be used to set as a simple criterion to expand the possibility of using laparoscopic surgery for the treatment of intramucosal poorly differentiated EGC.

Propofol is a neuroprotective anesthetic. Whether propofol can promote spinal cord injury repair by bone marrow mesenchymal stem cells remains poorly understood. We used rats to investigate spinal cord injury repair using bone marrow mesenchymal stem cell transplantation combined with propofol administration via the tail vein. Rat spinal cord injury was clearly alleviated; a large number of newborn non-myelinated and myelinated nerve fibers appeared in the spinal cord, the numbers of CM-Dil-labeled bone marrow mesenchymal stem cells and fluorogold-labeled nerve fibers were increased and hindlimb motor function of spinal cord-injured rats was markedly improved. These improvements were more prominent in rats subjected to bone marrow mesenchymal cell transplantation combined with propofol administration than in rats receiving monotherapy. These results indicate that propofol can enhance the therapeutic effects of bone marrow mesenchymal stem cell transplantation on spinal cord injury in rats.

The present study was done to determine whether kaempferol, a natural polyphenol of the flavonoid family, affects Epithelial-Mesenchymal Transition (EMT) in non-small cell lung cancer cells. Kaempferol not only inhibited cancer cell proliferation and migration in a dose-dependent manner but also modulated the expression of EMT-related proteins E-cadherin and vimentin which are indispensible to cellular motility, invasiveness and metastasis. These results indicate that kaempferol suppresses non-small cell lung cancer migration by modulating the expression of EMT proteins. Therefore, kaempferol may be useful as a potential anticancer agent for non-small cell lung cancer.

AIM: To investigate the predictive factors of lymph node metastasis (LNM) in poorly differentiated early gastric cancer (EGC), and enlarge the possibility of using laparoscopic wedge resection (LWR). METHODS: We retrospectively analyzed 85 patients with poorly differentiated EGC who underwent surgical resection between January 1992 and December 2010. The association between the clinicopathological factors and the presence of LNM was retrospectively analyzed by univariate and multivariate logistic regression analyses. Odds ratios (OR) with 95%CI were calculated. We further examined the relationship between the positive number of the three significant predictive factors and the LNM rate. RESULTS: In the univariate analysis, tumor size (P = 0.011), depth of invasion (P = 0.007) and lymphatic vessel involvement (P < 0.001) were significantly associated with a higher rate of LNM. In the multivariate model, tumor size (OR = 7.125, 95%CI: 1.251-38.218, P = 0.041), depth of invasion (OR = 16.624, 95%CI: 1.571-82.134, P = 0.036) and lymphatic vessel involvement (OR = 39.112, 95%CI: 1.745-123.671, P = 0.011) were found to be independently risk clinicopathological factors for LNM. Of the 85 patients diagnosed with poorly differentiated EGC, 12 (14.1%) had LNM. The LNM rates were 5.7%, 42.9% and 57.1%, respectively in cases with one, two and three of the risk factors respectively in poorly differentiated EGC. There was no LNM in 29 patients without the three risk clinicopathological factors. CONCLUSION: LWR alone may be sufficient treatment for intramucosal poorly differentiated EGC if the tumor is less than or equal to 2.0 cm in size, and when lymphatic vessel involvement is absent at postoperative histological examination.