We investigate how the random long-range interactions affect the synchronization features in networks of inertial ratchets,where each ratchet is driven by a periodic time-dependent external force,under the influence of an asymmetric periodic potential.It is found that for a given coupling strength𝐶,the synchronization of the coupled ratchets is induced as the fraction of random long-range interactions𝑝increases and the ratchet networks reach full synchronization for a larger𝑝.It is also found that the system reaches synchronization more effectively for a stronger coupling strength.
Schwann cells play a critical role in peripheral nerve regeneration through dedifferentiation and proliferation. In a previous study, we performed microarray analysis of the sciatic nerve after injury. Accordingly, we predicted that long non-coding RNA NONMMUG014387 may promote Schwann cell proliferation after peripheral nerve injury, as bioinformatic analysis revealed that the target gene of NONMMUG014387 was collagen triple helix repeat containing 1(Cthrc1). Cthrc1 may promote cell proliferation in a variety of cells by activating Wnt/PCP signaling. Nonetheless, bioinformatic analysis still needs to be verified by biological experiment. In this study, the candidate long non-coding RNA, NONMMUG014387, was overexpressed in mouse Schwann cells by recombinant adenovirus transfection. Plasmid p HBAd-MCMV-GFP-NONMMUG014387 and p HBAd-MCMV-GFP were transfected into Schwann cells. Schwann cells were divided into three groups: control(Schwann cells without intervention), Ad-GFP(Schwann cells with GFP overexpression), and Ad-NONMMUGO148387(Schwann cells with GFP and NONMMUGO148387 overexpression). Cell Counting Kit-8 assay was used to evaluate proliferative capability of mouse Schwann cells after NONMMUG014387 overexpression. Polymerase chain reaction and western blot assay were performed to investigate target genes and downstream pathways of NONMMUG014387. Cell proliferation was significantly increased in Schwann cells overexpressing lnc RNA NONMMUG014387 compared with the other two groups. Further, compared with the control group, m RNA and protein levels of Cthrc1, Wnt5 a, ROR2, Rho A, Rac1, JNK, and ROCK were visibly up-regulated in the Ad-NONMMUGO148387 group. Our findings confirm that long non-coding RNA NONMMUG014387 can promote proliferation of Schwann cells surrounding the injury site through targeting Cthrc1 and activating the Wnt/PCP pathway.
Bin PanZhong-ju ShiJia-yin YanJia-he LiShi-qing Feng
Background Low-density lipoprotein (LDL) receptor is normally regulated via a feedback system that is dependent on intracellular cholesterol levels. We have demonstrated that cytokines disrupt cholesterol-mediated LDL receptor feedback regulation causing intracellular accumulation of unmodified LDL in peripheral cells. Liver is the central organ for lipid homeostasis. The aim of this study was to investigate the regulation of cholesterol exogenous uptake via LDL receptor and its underlying mechanisms in human hepatic cell line (HepG2) cells under physiological and inflammatory conditions. Methods Intracellular total cholesterol (TC), free cholesterol (FC) and cholesterol ester (CE) were measured by an enzymic assay. Oil Red O staining was used to visualize lipid droplet accumulation in cells. Total cellular RNA was isolated from cells for detecting LDL receptor, sterol regulatory element binding protein (SREBP)-2 and SREBP cleavage-activating protein (SCAP) mRNA levels using real-time quantitative PCR. LDL receptor and SREBP-2 protein expression were examined by Western blotting. Confocal microscopy was used to investigate the translocation of SCAP-SREBP complex from the endoplasmic reticulum (ER) to the Golgi by dual staining with anti-human SCAP and anti-Golgin antibodies. Results LDL loading increased intracellular cholesterol level, thereby reduced LDL receptor mRNA and protein expression in HepG2 cells under physiological conditions. However, interleukin 1β (IL-1β) further increased intracellular cholesterol level in the presence of LDL by increasing both LDL receptor mRNA and protein expression in HepG2. LDL also reduced the SREBP and SCAP mRNA level under physiological conditions. Exposure to IL-1β caused over-expression of SREBP-2 and also disrupted normal distribution of SCAP-SREBP complex in HepG2 by enhancing translocation of SCAP-SREBP from the ER to the Golgi despite a high concentration of LDL in the culture medium. Conclusions IL-1β disrupts cholesterol-media
CHEN Ya-xiRUAN Xiong-zhongHUANG Ai-longLI QiuJohn F. MoorheadZac Varghese
Dynamic recrystallization (DRX) behaviors of a heat-resistant martensitic stainless steel 403Nb during hot deformation have been investigated by single-pass thermo-mechanical simulative experiment at temperatures of 900-1150℃ and strain rates of 0.01-1 s-1 The results show that the true stress-true strain curves of this alloy can be classified into two types, one is of dynamic recovery and the other is of dynamic recrystallization. The DRX in 403Nb alloy is easy to occur at strain rates lower than 0.5 s-1 and deformation temperatures higher than 1000℃. Using regression analysis, the stress multiplier (a) and apparent stress exponent (n) were calculated to be 0.0153 and 3.22, respectively, while the activation energy (Qd) for DRX of 403Nb was calculated to be 367.293 kJ/mol. The constitutive equation of peak stress for DRX was also obtained. Based on P-J method, the critical strain for DRX was accurately determined. The mathematical models of peak strain and kinetic equation for DRX of 403Nb steel were finally established.
The liver plays a major role in the regulation , glucose, lipid and energy metabolism. Increasd hepatic fat deposit is a very common feature in obese, insulin-resistant patients, in metabolic syndrome, alcoholic steatohepatitis (ASH) and nonalchoholic fatty liver disaseas (NAFLD). As a central organ for whole body lipid metabolism, disruption of the normal mechanisms for synthesis, transport and removal/ metabolism of long-chain fatty acids and triglycerides are the basis for the development of fatty liver. The exact mechanisms that link hepatic lipid accumulation, impaired glucose metabolism, and insulin resistance are unknown, but increasing evidence suggest that nuclear transcription factors play important roles. Members of the nuclear receptor superfamily, especially the peroxisome proliferator-activated receptors (PPARs) and the liver X receptor (LXR), other factors such as sterol regulatory element binding proteins (SREBPs), carbohydrate- response element-binding protein (ChREBP), and nuclear transcription fator-κB (NF-κB) have emerged as dominant regulators of these processes, but the relative role of each of these factors in fatty liver disease is still undefined.
CHEN Ya-xi HUANG Ai-long RUAN Xiong-zhong Centre for Lipid Research,Key Laboratory of Molecular Biology on Infectious Diseases,Ministry of Education
A coupled thermo-mechanical model containing metal flow and temperature field for calculating temperature variation has been developed on fourteen-pass hot continuous rolling of round rod for Inconel 718 alloy using 3D elastic-plastic finite element method (FEM). The temperature of characteristic analysis points in the intermediate cross-section of the workpiece has been simulated at initial temperature ranging from 960 to 1000 ℃ and initial velocity in range of 0.15-0.55 m·s^-1. Based on finite element analysis and microstructural observation in cylindrical hot compression experiments, the appropriate hot continuous rolling technologies have been designed for rod products with different diameters. For a real rolling practice, the simulated surface temperature was examined and is in good agreement with the measured one.
Fengli SUILiqing CHENXianghua LIULintao WANGWei LI
BACKGROUND Whether regional lymphadenectomy(RL)should be routinely performed in patients with T1b gallbladder cancer(GBC)remains a subject of debate.AIM To investigate whether RL can improve the prognosis of patients with T1b GBC.METHODS We studied a multicenter cohort of patients with T1b GBC who underwent surgery between 2008 and 2016 at 24 hospitals in 13 provinces in China.The logrank test and Cox proportional hazards model were used to compare the overall survival(OS)of patients who underwent cholecystectomy(Ch)+RL and those who underwent Ch only.To investigate whether combined hepatectomy(Hep)improved OS in T1b patients,we studied patients who underwent Ch+RL to compare the OS of patients who underwent combined Hep and patients who did not.RESULTS Of the 121 patients(aged 61.9±10.1 years),77(63.6%)underwent Ch+RL,and 44(36.4%)underwent Ch only.Seven(9.1%)patients in the Ch+RL group had lymph node metastasis.The 5-year OS rate was significantly higher in the Ch+RL group than in the Ch group(76.3%vs 56.8%,P=0.036).Multivariate analysis showed that Ch+RL was significantly associated with improved OS(hazard ratio:0.51;95%confidence interval:0.26-0.99).Among the 77 patients who underwent Ch+RL,no survival improvement was found in patients who underwent combined Hep(5-year OS rate:79.5%for combined Hep and 76.1%for no Hep;P=0.50).CONCLUSION T1b GBC patients who underwent Ch+RL had a better prognosis than those who underwent Ch.Hep+Ch showed no improvement in prognosis in T1b GBC patients.Although recommended by both the National Comprehensive Cancer Network and Chinese Medical Association guidelines,RL was only performed in 63.6%of T1b GBC patients.Routine Ch+RL should be advised in T1b GBC.
The essential role of ethylene in fruit ripening has been thoroughly studied.However,the involvement of brassinosteroids(BRs)in the regulation of fruit ripening and their relationship with the ethylene pathway are poorly understood.In the current study,we found that BRs were actively synthesized during tomato fruit ripening.We then generated transgenic lines overexpressing or silencing SlCYP90B3,which encodes a cytochrome P450 monooxygenase that catalyzes the rate-limiting step of BR synthesis.The expression level of SlCYP90B3 was positively related to the contents of bioactive BRs as well as the ripening process in tomato fruit,including enhanced softening and increased soluble sugar and flavor volatile contents.Both carotenoid accumulation and ethylene production were strongly correlated with the expression level of SlCYP90B3,corroborated by the altered expression of carotenoid biosynthetic genes as well as ethylene pathway genes in transgenic tomato fruits.However,the application of the ethylene perception inhibitor 1-methycyclopropene(1-MCP)abolished the promotion effect of SlCYP90B3 overexpression on carotenoid accumulation.Taken together,these results increase our understanding of the involvement of SlCYP90B3 in bioactive BR biosynthesis as well as fruit ripening in tomato,thus making SlCYP90B3 a target gene for improvement of visual,nutritional and flavor qualities of tomato fruits with no yield penalty.
Based on the exploratory spatial data analysis (ESDA) technique and geographic information system (GIS) platform, with statistic data of counties in 2005, this paper confirms that there is a large population density gap between counties in 2005 because the Gini coefficient is 0.55. Population distribution does not change a lot during the past decades, and the southeast China is still much more densely populated than the northwest China. The global spa- tial autoeorrelation of population distribution is obvious because Moran's I scores 0.42 and local spatial autocorrelation is partly significant. Climate and elevation are still the main natural influ- encing factors. Meanwhile industrial structure and transportation significantly influence population distribution. Different combinations of natural factors have different effects on population distribution. For a long term, climate and terrain factor stability affect population distribution. But its influence will be weakened by progress of technology. Economic development is the main factor that changes population distribution for a short term.
Cucumis hystrix Chakr.(2n=2x=24)is a wild species that can hybridize with cultivated cucumber(C.sativus L.,2n=2x=14),a globally important vegetable crop.However,cucumber breeding is hindered by its narrow genetic base.Therefore,introgression from C.hystrix has been anticipated to bring a breakthrough in cucumber improvement.Here,we report the chromosome-scale assembly of C.hystrix genome(289 Mb).Scaffold N50 reached 14.1 Mb.Over 90%of the sequences were anchored onto 12 chromosomes.A total of 23,864 genes were annotated using a hybrid method.Further,we conducted a comprehensive comparative genomic analysis of cucumber,C.hystrix,and melon(C.melo L.,2n=2x=24).Whole-genome comparisons revealed that C.hystrix is phylogenetically closer to cucumber than to melon,providing a molecular basis for the success of its hybridization with cucumber.Moreover,expanded gene families of C.hystrix were significantly enriched in“defense response,”and C.hystrix harbored 104 nucleotide-binding site-encoding disease resistance gene analogs.Furthermore,121 genes were positively selected,and 12(9.9%)of these were involved in responses to biotic stimuli,which might explain the high disease resistance of C.hystrix.The alignment of whole C.hystrix genome with cucumber genome and self-alignment revealed 45,417 chromosome-specific sequences evenly distributed on C.hystrix chromosomes.Finally,we developed four cucumber-C.hystrix alien addition lines and identified the exact introgressed chromosome using molecular and cytological methods.The assembled C.hystrix genome can serve as a valuable resource for studies on Cucumis evolution and interspecific introgression breeding of cucumber.