35 research outputs found

    Effects of artemisinin on ventricular arrhythmias in response to left ventricular afterload increase and microRNA expression profiles in Wistar rats

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    Background Patients with dilated cardiomyopathy, increased ventricular volume, pressure overload or dysynergistic ventricular contraction and relaxation are susceptible to develop serious ventricular arrhythmias (VA). These phenomena are primarily based on a theory of mechanoelectric feedback, which reflects mechanical changes that produce alterations in electrical activity. However, very few systematic studies have provided evidence of the preventive effects of artemisinin (ART) on VA in response to left ventricle (LV) afterload increases. MicroRNAs (miRNAs) are endogenous small non-coding RNAs that regulate expression of multiple genes by suppressing mRNAs post-transcriptionally. Aims The aims of this study were to investigate preventive effects of ART on mechanical VA and the underling molecular mechanisms of differentially expressed miRNAs (DEMs). Methods For the study, 70 male Wistar rats were randomly divided into seven groups: group 1 was a control group (sham surgery); group 2 was a model group that underwent transverse aortic constriction (TAC) surgery; groups 3, 4, 5 and 6 were administered ART 75, 150, 300 and 600 mg/kg before TAC surgery, respectively; and group 7 was administered verapamil (VER) 1 mg/kg before TAC surgery. A ventricular arrhythmia score (VAS) was calculated to evaluate preventive effects of ART and VER on mechanical VA. The high throughput sequencing-based approach provided DEMs that were altered by ART pretreatment between group 2 and group 4. All predicted mRNAs of DEMs were enriched by gene ontology (GO) and Kyoto Encyclopedia annotation of Genes and Genomes (KEGG) databases. These DEMs were validated by a real time quantitative polymerase chain reaction (RT-qPCR). Results The average VASs of groups 3, 4, 5, 6 and 7 were significantly reduced compared with those of group 2 (2.70 ± 0.48, 1.70 ± 0.95, 2.80 ± 0.79, 2.60 ± 0.97, 1.40 ± 0.52, vs 3.70 ± 0.67, p < 0.01, respectively). The three top GO terms were neuron projection, organ morphogenesis and protein domain specific binding. KEGG enrichment of the 16 DEMs revealed that MAPK, Wnt and Hippo signaling pathways were likely to play a substantial role in the preventive effects of ART on mechanical VA in response to LV afterload increases. All candidate DEMs with the exception of rno-miR-370-3p, rno-miR-6319, rno-miR-21-3p and rno-miR-204-5p showed high expression levels validated by RT-qPCR. Conclusions Artemisinin could prevent mechanical VA in response to LV afterload increases. Validated DEMs could be biomarkers and therapeutic targets of ART regarding its prevention of VA induced by pressure overload. The KEGG pathway and GO annotation analyses of the target mRNAs could indicate the potential functions of candidate DEMs. These results will help to elucidate the functional and regulatory roles of candidate DEMs associated with antiarrhythmic effects of ART

    Motion Planning of Autonomous Mobile Robot Using Recurrent Fuzzy Neural Network Trained by Extended Kalman Filter

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    This paper proposes a novel motion planning method for an autonomous ground mobile robot to address dynamic surroundings, nonlinear program, and robust optimization problems. A planner based on the recurrent fuzzy neural network (RFNN) is designed to program trajectory and motion of mobile robots to reach target. And, obstacle avoidance is achieved. In RFNN, inference capability of fuzzy logic and learning capability of neural network are combined to improve nonlinear programming performance. A recurrent frame with self-feedback loops in RFNN enhances stability and robustness of the structure. The extended Kalman filter (EKF) is designed to train weights of RFNN considering the kinematic constraint of autonomous mobile robots as well as target and obstacle constraints. EKF’s characteristics of fast convergence and little limit in training data make it suitable to train the weights in real time. Convergence of the training process is also analyzed in this paper. Optimization technique and update strategy are designed to improve the robust optimization of a system in dynamic surroundings. Simulation experiment and hardware experiment are implemented to prove the effectiveness of the proposed method. Hardware experiment is carried out on a tracked mobile robot. An omnidirectional vision is used to locate the robot in the surroundings. Forecast improvement of the proposed method is then discussed at the end

    Life cycle economic analysis of fuel ethanol derived from cassava in southwest China

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    For energy security and environmental improvement reasons, the Chinese government is developing biomass ethanol as one of its transportation fuels. Cassava is a good feedstock to produce this ethanol because it has a high starch content and it is abundant in the southern provinces. A computer-based cost model has been developed to assess the life cycle economics of ethanol produced from cassava. The results are compared to gasoline as a base-line case. Although ethanol fuel is not currently competitive with conventional gasoline, these life cycle cost results indicate that, at present market prices, ethanol has the potential to be competitive if there are incentives and improved cassava yields. In addition, this renewable energy could help to alleviate poverty, improve land utilization and bring energy independence in Guangxi province in southeast China. This computer model will be an important tool for the energy policy makers to understand whether an energy alternative is cost-competitive, as well as providing a way to find appropriate measures throughout the entire life cycle that optimizes the process and removes the economic barriers.Life cycle assessment Cassava Fuel ethanol Economic analysis

    Anti-Aging Effect of <i>Agrocybe aegerita</i> Polysaccharide through Regulation of Oxidative Stress and Gut Microbiota

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    Polysaccharides extracted from Agrocybe aegerita (AAPS) have various physiological effects. In this study, we used the naturally aging Drosophila melanogaster and D-galactose-induced aging mice as animal models to study the anti-aging effects of AAPS via the alleviation of oxidative stress and regulation of gut microbiota. Results showed that AAPS could significantly prolong lifespan and alleviate oxidative stress induced by H2O2 of Drosophila melanogaster. In addition, AAPS significantly increased the activities of antioxidant enzymes in Drosophila melanogaster and mice, and reduced the content of MDA. Furthermore, AAPS reshaped the disordered intestinal flora, increased the abundance ratio of Firmicutes to Bacteroidetes, and increased the abundance of beneficial bacteria Lactobacillus. Our results demonstrated that AAPS had good antioxidant and potential anti-aging effects in vivo

    Dihydrotanshinone I Inhibits the Lung Metastasis of Breast Cancer by Suppressing Neutrophil Extracellular Traps Formation

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    Breast cancer (BC) is a common female malignancy, worldwide. BC death is predominantly caused by lung metastasis. According to previous studies, Dihydrotanshinone I (DHT), a bioactive compound in Salvia miltiorrhiza Bunge (S. miltiorrhiza), has inhibitory effects on numerous cancers. Here, we investigated the anti-metastatic effect of DHT on BC, where DHT more strongly inhibited the growth of BC cells (MDA-MB-231, 4T1, MCF-7, and SKBR-3) than breast epithelial cells (MCF-10a). Additionally, DHT repressed the wound healing, invasion, and migration activities of 4T1 cells. In the 4T1 spontaneous metastasis model, DHT (20 mg/kg) blocked metastasis progression and distribution in the lung tissue by 74.9%. DHT reversed the formation of neutrophil extracellular traps (NETs) induced by phorbol 12-myristate 13-acetate, as well as ameliorated NETs-induced metastasis. Furthermore, it inhibited Ly6G+Mpo+ neutrophils infiltration and H3Cit expression in the lung tissues. RNA sequencing, western blot, and bioinformatical analysis indicated that TIMP1 could modulate DHT acting on lung metastasis inhibition. The study demonstrated a novel suppression mechanism of DHT on NETs formation to inhibit BC metastasis

    Giant cell tumor of the tendon sheath: A rare case in the left knee of a 15-year-old boy

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    Localized forms of giant cell tumors are defined as giant cell tumors of the tendon sheath (GCTTS). GCTTS arises from the synovium of a joint, bursa or tendon sheath, and 85% of the tumors occur in the fingers. GCTTS in the knee is extremely rare. We report an unusual case of a 15-year-old boy who presented with an occult growing swelling and a 2-month history of infra-patellar pain in the left knee. Magnetic resonance imaging (MRI) demonstrated a well-circumscribed soft tissue mass in the infra-patellar fat pad posterior to the patella tendon. Excision biopsy was performed by surgical removal. Histopathological examination revealed that it was GCTTS. During the follow-up period, his recovery was propitious and there was no recurrence. Owing to its few and non-specific symptoms, and local recurrence varying from 9 to 44%, its proper, early diagnosis and appropriate treatment is necessary. The purpose for which we report the case is to emphasize the possibility of GCTTS where there is a mass with non-specific symptoms such as infra-patellar pain of the knee, and to avoid misdiagnosis where possible
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