Subject: Medicine And Pharmacology, Cardiac And Cardiovascular Systems Keywords: Aerobic exercise; Myocardial ischemia/reperfusion; autophagy; SIRT3; SOD2; NF-κB; Biochemical indicators
Online: 1 April 2021 (13:28:32 CEST)
Objective: The purpose of this study was to investigate the effect of aerobic exercise on myocardial injury induced by I/ R in rats by regulating SIRT3/SOD2/NF-κB signaling pathway, and to provide theoretical guidance for clinical treatment of myocardial I/R injury.Methods:SPF Male Sprague-Dawley(SD) rats were randomly assigned to 4 groups: Sham operation group(n=10), I/R group(n=10), Aerobic exercise group(n=10)and Aerobic exercise+κ-receptor antagonist group(Pro DTC group，n=10). The left anterior descending coronary artery(LAD) of rats was ligated and re-canalized to establish I/R rat model. Hematoxylin-eosin(HE) staining was performed to examine histological morphology in myocardial tissues of each group. The biological analysis was performed to measure cTnI、CK-MB、BNP levels in blood samples of each group. The expression levels of SOD2, TLR4, and p65 in myocardial tissues were measured by immunohistochemical assay. The influence of aerobic exercise on Beclin-1 、LC3II/I、SIRT3, TLR4, and phosphorylated p65 was measured by Western blotting.Results: The result of histological morphology examination revealed that Aerobic exercise group exhibited integrated cardiac myofilament, less inflammatory cell infiltration, as much as significantly decreased cellular edema. Measurement of cTnI、CK-MB、BNP revealed that oxycodone post-treatment reduces the injury of myocardial tissues(P<0.05). Immunohistochemical staining results revealed that aerobic exercise clearly decreased the expression of TLR4 and p65, and increased the expression of SOD2(P<0.05). Besides, Western blotting revealed that aerobic exercise down-regulated the expression of Beclin-1 、LC3II/I、TLR4 and phosphorylated p65, up-regulated the expression of SIRT3(P<0.05).Conclusions: Aerobic exercise significantly improved myocardial I/R injury. The mechanisms may be associated with activating κ-receptor to regulate SIRT3/SOD2/NF-κB pathway.
ARTICLE | doi:10.20944/preprints202307.0326.v1
Subject: Engineering, Mechanical Engineering Keywords: Contact Fatigue; Feature Extraction; Health Index; Degradation Prediction; Temporal Convolutional Network; Convolutional Auto-Encoder Network
Online: 5 July 2023 (14:04:06 CEST)
In order to realize the performance degradation trend prediction accurately, a prediction method based on multi-domain features and temporal convolutional network (TCN) is proposed. Firstly, construct a high-dimensional feature set in the multi-domain of vibration signals, and use comprehensive evaluation indicators to preliminarily screen performance degradation indexes with good sensitivity and strong trend. Secondly, the kernel principal component analysis (KPCA) method is adopted to eliminate redundant information between multi-domain features, and construct a health index (HI) based on convolutional auto-encoder (CAE) network. Thirdly, a TCN-based performance degradation trend prediction model is constructed, and direct multi-step prediction is used to predict the performance degradation trend of the monitored object. On this basis, the validity of the proposed method is verified using the bearing public data, and it is successfully applied to performance degradation trend prediction of rolling contact fatigue specimen. The results show that the feature set can be reduced from 14 dimensions to 4 dimensions by using KPCA, while 98.33% of the information of the original feature set is retained. Furthermore, the method of constructing HI based on CAE network is effective. The change process of the HI constructed truly reflects the performance degradation process of the rolling contact fatigue specimen. Compared with the two commonly used HI construction methods, auto-encoding (AE) network and gaussian mixture model (GMM), this method has obvious advantages. At the same time, the prediction model based on TCN can accurately predict the performance degradation of the rolling contact fatigue specimen with the root mean square error 0.0146 and the mean absolute error 0.0105, which has better performance and higher prediction accuracy than the prediction model based on the long short-term memory (LSTM) network and the gated recurrent unit (GRU). This method has general significance and may be extended to the performance degradation prediction of other mechanical equipment/parts.
ARTICLE | doi:10.20944/preprints201910.0156.v1
Subject: Biology And Life Sciences, Virology Keywords: noni mosaic virus; potyvirus; complete genome; morinda citrifolia l; illumina transcriptomic sequencing
Online: 14 October 2019 (09:29:57 CEST)
An outbreak of a virus-like disease has caused severe damage to noni plants (Morinda citrifolia L.) in Xishuangbanna area of China's southwestern Yunnan province since 2015. The diseased plants displayed typical mosaic symptom with light and dark green patches on leaves. Flexuous filamentous virus particles of about 800 nm in length were observed from the leaf saps by transmission electron microscope. Illumina transcriptomic sequencing further revealed the presence of a potyvirus and its near complete genome was obtained from de novo assembly. The complete genome of 9,659 nts was obtained by Sanger sequencing of eight amplicons generate by RT-PCR and 5’ and 3’ RACE. BLASTp analysis of the polyprotein sequence showed that the virus was most closely related to Tobacco vein banding mosaic virus (TVBMV), but these two viruses only shared 50.7% amino acid sequence similarity. Both phylogenetic analyses of the polyprotein and CP amino acid sequences indicated that this virus is a member of genus Potyvirus. However, the low sequence homology with all known potyviruses established this virus as a new species in the genus, tentatively named as Noni mosaic virus (NoMV). Our field surveys showed that 100% of the symptomatic samples and 28.57% of the asymptomatic samples were infected with this novel potyvirus. Aphids collected from diseased leaves were also detected carrying the virus. In summary, our data indicated that a novel species of potyvirus, NoMV, is prevalent in Yunnan, China and is associated with an emerging mosaic disease on M. citrifolia.
ARTICLE | doi:10.20944/preprints201910.0241.v1
Subject: Environmental And Earth Sciences, Atmospheric Science And Meteorology Keywords: coupled chemistry-meteorology data assimilation; weak and strong data assimilation coupling; Canadian Quick Covariance method (CQC); assimilation of MIPAS temperature observations; ozone-temperature cross-covariance; tracer-wind 4D-Var assimilation
Online: 21 October 2019 (05:09:58 CEST)
We examine data assimilation coupling between meteorology and chemistry in the stratosphere from both weak and strong coupling strategies. The study was performed with the Canadian operational weather prediction Global Environmental Multiscale (GEM) model coupled online with the photochemical stratospheric chemistry developed at the Belgian Institute for Space Aeronomy, described in Part I. Here, the Canadian Meteorological Centre’s operational variational assimilation system was extended to include errors of chemical variables and cross-covariances between meteorological and chemical variables in a 3D-Var configuration, and we added the adjoint of tracer advection in the 4D-Var configuration. Our results show that the assimilation of limb sounding observations from the MIPAS instrument on board Envisat can be used to anchor the AMSU-A radiance bias correction scheme. Also, the added value of limb sounding temperature observations on meteorology and transport is shown to be significant. Weak coupling data assimilation with ozone-radiation interaction is shown to give comparable on meteorology whether a simplified linearized or comprehensive ozone chemistry scheme is used. Strong coupling data assimilation, using static error cross-covariances between ozone and temperature in a 3D-Var context, produced inconclusive results with the approximations we used. We have also conducted the assimilation of long-lived species observations using 4D-Var to infer winds. Our results showed the added value of assimilating several long-lived species, and an improvement in the zonal wind in the Tropics within the troposphere and lower stratosphere. 4D-Var assimilation also induced a correction of zonal wind in the surf zone and a temperature bias in the lower tropical stratosphere
Subject: Chemistry And Materials Science, Biomaterials Keywords: transforming growth factor β3; chitosan sponge; human periodontal ligament cells; osteogenic differentiation
Online: 11 September 2019 (13:42:18 CEST)
Abstract: Periodontal disease is the main reason for tooth loss in adults. Tissue engineering and regenerative medicine are the advanced technologies used to manage soft and hard tissue defects caused by periodontal disease. We developed a transforming growth factor-β3 chitosan sponge (TGF-β3/CS) to repair periodontal soft and hard tissue defects. We investigated the proliferation and osteogenic differentiation behaviors of primary human periodontal ligament stem cells (hPDLSCs) to discuss the bioactivity and application of TGF-β3 in periodontal disease. We separately used Calcein-AM/PI double-labeling or CM-Dil-labeling coupled with fluorescence microscopy to trace the survival and function of the cells after implantation in vitro or in vivo. The mineralization of osteogenic differentiated hPDLSCs was confirmed by measuring ALP activity and calcium content. The levels of COL I, ALPL, TGF-βRI, TGF-βRII, and Pp38/t-p38 were tested using Western blot to explore the mechanism of bone repair prompted by TGF-β3. When hPDLSCs were inoculated with different concentrations of TGF-β3/CS (62.5–500 ng/mL), ALP activity was the highest in TGF-β3 (250 ng/mL) group after seven days (P < 0.05 vs. control); the calcium content in each group increased significantly after 21 and 28 days (P < 0.001 vs. control). The best result was achieved in the TGF-β3 (500 ng/mL) group. All results showed that TGF-β3/CS can promote osteogenic differentiation of hPDLSC and may be involved in the p38 MAPK signaling pathway. TGF-β3/CS has the potential for application in the repair of incomplete alveolar bone defects.
ARTICLE | doi:10.20944/preprints202110.0284.v1
Subject: Biology And Life Sciences, Ecology, Evolution, Behavior And Systematics Keywords: Watershed; biogeographic patterns; microbial biogeography; biodiversity; spatial distribution; research unit
Online: 20 October 2021 (09:34:27 CEST)
Biogeography research is flawed by the poor understanding of microbial distributions due to the lack of a systematic research framework, especially regarding appropriate study units. By combining pure culture and molecular methods, we studied the biogeographic patterns of nematode-trapping fungi by collecting and analysing 2,250 specimens from 228 sites in Yunnan Province, China. We found typical watershed patterns at the species and genetic levels of nematode-trapping fungi. The results showed that microbial biogeography could be better understood by 1) using watersheds as research units, 2) removing the coverup of widespread species, and 3) applying good sampling efforts and strategies. We suggest that watersheds could help unify the understanding of the biogeographic patterns of animals, plants, and microbes and may also help account for the historical and contemporary factors driving species distributions.