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81.
Brain-to-brain interfaces(BtBIs) hold exciting potentials for direct communication between individual brains. However,technical challenges often limit their performance in rapid information transfer. Here, we demonstrate an optical brain-to-brain interface that transmits information regarding locomotor speed from one mouse to another and allows precise, real-time control of locomotion across animals with high information transfer rate. We found that the activity of the genetically identified neuromedin B(NMB) neurons within the nucleus incertus(NI) precisely predicts and critically controls locomotor speed. By optically recording Ca~(2+) signals from the NI of a "Master" mouse and converting them to patterned optogenetic stimulations of the NI of an "Avatar" mouse, the Bt BI directed the Avatar mice to closely mimic the locomotion of their Masters with information transfer rate about two orders of magnitude higher than previous Bt BIs. These results thus provide proof-of-concept that optical Bt BIs can rapidly transmit neural information and control dynamic behaviors across individuals.  相似文献   
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83.
Soil organic carbon (SOC), the largest terrestrial carbon pool, plays a significant role in soil‐related ecosystem services such as climate regulation, soil fertility and agricultural production. However, its fate under land use change is difficult to predict. A major issue is that SOC comprised of numerous organic compounds with potentially distinct and poorly understood turnover properties. Here we use spatiotemporal measurements of the particulate (POC), mineral‐associated (MOC) and charred SOC (COC) fractions from 176 trials involving changes in land use to assess their underlying controls. We find that the initial pool sizes of each of the three fractions consistently and dominantly control their temporal dynamics after changes in land use (i.e. the baseline effects). The effects of climate, soil physicochemical properties and plant residues, however, are fraction‐ and time‐dependent. Climate and soil properties show similar importance for controlling the dynamics of MOC and COC, while plant residue inputs (in term of their quantity and quality) are much less important. For POC, plant residues and management practices (e.g. the frequency of pasture in crop‐pasture rotation systems) are substantially more important, overriding the influence of climate. These results demonstrate the pivotal role of measuring SOC composition and considering fraction‐specific stabilization and destabilization processes for effective SOC management and reliable SOC predictions.  相似文献   
84.
Chen  S. L.  Zhang  L. P.  Cai  X. M.  Bian  L.  Luo  Z. X.  Li  Z. Q.  Ge  L. G.  Chen  Z. M.  Xin  Z. J. 《Russian Journal of Plant Physiology》2020,67(3):572-580
Russian Journal of Plant Physiology - The tea geometrid Ectropis grisescens is an important pest of tea plant (Camellia sinensis (L.) O. Kuntze). It feeds on the new leaves and tender...  相似文献   
85.
The aim of this study was to explore the effects of platelet‐rich plasma on gingipain‐caused changes in cell morphology and apoptosis of osteoblasts. Mouse osteoblasts MC3T3‐E1 cells were treated with gingipain extracts from Porphyromonas gingivalis in the presence or absence of platelet‐rich plasma. Apoptosis was detected with terminal deoxynucleotidyl transferase‐mediated dUTP nick‐end labeling staining. F‐actin was determined by phalloidin‐fluorescent staining and observed under confocal microscopy. Western blot analysis was used to detect integrin β1, F‐actin, and G‐actin protein expressions. A knocking down approach was used to determine the role of integrin β1. The platelet‐rich plasma protected osteoblasts from gingipain‐induced apoptosis in a dose‐dependent manner, accompanied by upregulation of integrin β1. Platelet‐rich plasma reversed the loss of F‐actin integrity and decrease of F‐actin/G‐actin ratio in osteoblasts in the presence of gingipains. By contrast, the effects of platelet‐rich plasma were abrogated by knockdown of integrin β1. The platelet‐rich plasma failed to reduce cell apoptosis and reorganize the cytoskeleton after knockdown of integrin β1. In conclusion, platelet‐rich plasma inhibits gingipain‐induced osteoblast apoptosis and actin cytoskeleton disruption by upregulating integrin β1 expression.  相似文献   
86.
Luo  Xiaodong  Quan  Hui 《Statistics in biosciences》2020,12(2):216-224
Statistics in Biosciences - Weighted log-rank statistics and recently weighted win loss statistics are often used to test the null hypothesis that the treatment group and the control group have no...  相似文献   
87.
88.
Huang  Xiaoling  Zou  Xian  Xu  Zhiqian  Tang  Fei  Shi  Junsong  Zheng  Enqin  Liu  Dewu  Moisyadi  Stefan  Urschitz  Johann  Wu  Zhenfang  Li  Zicong 《Transgenic research》2020,29(3):307-319

Genetically modified (GM) pigs hold great promises for pig genetic improvement, human health and life science. When GM pigs are produced, selectable marker genes (SMGs) are usually introduced into their genomes for host cell or animal recognition. However, the SMGs that remain in GM pigs might have multiple side effects. To avoid the possible side effects caused by the SMGs, they should be removed from the genome of GM pigs before their commercialization. The Cre recombinase is commonly used to delete the LoxP sites-flanked SMGs from the genome of GM animals. Although SMG-free GM pigs have been generated by Cre-mediated recombination, more efficient and cost-effective approaches are essential for the commercialization of SMG-free GM pigs. In this article we describe the production of a recombinant Cre protein containing a cell-penetrating and a nuclear localization signal peptide in one construct. This engineered Cre enzyme can efficiently excise the LoxP-flanked SMGs in cultured fibroblasts isolated from a transgenic pig, which then can be used as nuclear donor cells to generate live SMG-free GM pigs harboring a desired transgene by somatic cell nuclear transfer. This study describes an efficient and far-less costly method for production of SMG-free GM pigs.

  相似文献   
89.
Objective: Long non-coding RNAs (lncRNAs) recently have been identified as influential indicators in a variety of malignancies. The aim of the present study was to identify a functional lncRNA LINC00488 and its effects on thyroid cancer in the view of cell proliferation and apoptosis.Methods: In order to evaluate the effects of LINC00488 on the cellular process of thyroid cancer, we performed a series of in vitro experiments, including cell counting kit-8 (CCK-8) assay, EdU (5-ethynyl-2′-deoxyuridine) assay, flow cytometry, transwell chamber assay, Western blot and RT-qPCR. The target gene of LINC00488 was then identified by bioinformatics analysis (DIANA and TargetScan). Finally, a series of rescue experiments was conducted to validate the effect of LINC00488 and its target genes on proliferation, migration, invasion and apoptosis of thyroid cancer.Results: Our findings revealed that LINC00488 was highly expressed in thyroid cancer cell lines (BCPAP, BHP5-16, TPC-1 and CGTH-W3) and promoted the proliferation, migration and invasion, while inhibited the apoptosis of thyroid cancer cells (BCPAP and TPC-1). The results of bioinformatics analysis and dual luciferase reporter gene assay showed that LINC00488 could directly bind to miR-376a-3p and down-regulated the expression level of miR-376a-3p. In addition, Paraoxonase-2 (PON2) was a target gene of miR-376a-3p and negatively regulated by miR-376a-3p. Rescue experiment indicated that LINC00488 might enhance PON2 expression by sponging miR-376a-3p in thyroid cancer.Conclusion: Taken together, our study revealed that lncRNA LINC00488 acted as an oncogenic gene in the progression of thyroid cancer via regulating miR-376a-3p/PON2 axis, which indicated that LINC00488-miR-376a-3p-PON2 axis could serve as novel biomarkers or potential targets for the treatment of thyroid cancer.  相似文献   
90.
A high level of low-density lipoprotein cholesterol (LDL) is one of the most important risk factors for coronary artery disease (CAD), the leading cause of death worldwide. However, a low concentration of LDL may be protective. Genome-wide association studies revealed that variation in ADTRP gene increased the risk of CAD. In this study, we found that a low concentration of oxidized-LDL induced the expression of ADTRP. Further analyses showed that knockdown of the expression of LDL receptor genes LDLR, CD36, or LOX-1 significantly downregulated ADTRP expression, whereas overexpression of LDLR/CD36/LOX-1 markedly increased ADTRP expression through the NF-κB pathway. Like ADTRP, LDLR, CD36 and LOX-1 were all involved in endothelial cell (EC) functions relevant to the initiation of atherosclerosis. Downregulation of LDLR/CD36/LOX-1 promoted monocyte adhesion to ECs and transendothelial migration of monocytes by increasing expression of ICAM-1, VCAM-1, E-selectin and P-selectin, decreased EC proliferation and migration, and increased EC apoptosis, thereby promoting the initiation of atherosclerosis. Opposite effects were observed with the overexpression of ADTRP and LDLR/CD36/LOX-1 in ECs. Interestingly, through the NF-κB and AKT pathways, overexpression of ADTRP significantly upregulated the expression of LDLR, CD36, and LOX-1, and knockdown of ADTRP expression significantly downregulated the expression of LDLR, CD36, and LOX-1. These data suggest that ADTRP and LDL receptors LDLR/CD36/LOX-1 positively regulate each other, and form a positive regulatory loop that regulates endothelial cell functions, thereby providing a potential protective mechanism against atherosclerosis. Our findings provide a new molecular mechanism by which deregulation of ADTRP and LDLR/CD36/LOX-1 promote the development of atherosclerosis and CAD.  相似文献   
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