Protective mechanisms of micro RNA-27a against oxygen-glucose deprivation-induced injuries in hippocampal neurons

Hypoxic injuries during fetal distress have been shown to cause reduced expression of micro RNA-27a（mi R-27a）,which regulates sensitivity of cortical neurons to apoptosis.We hypothesized that miR-27 a overexpression attenuates hypoxia- and ischemia-induced neuronal apoptosis by regulating FOXO1,an important transcription factor for regulating the oxidative stress response.miR-27 a mimic was transfected into hippocampal neurons to overexpress miR-27 a.Results showed increased hippocampal neuronal viability and decreased caspase-3 expression.The luciferase reporter gene system demonstrated that mi R-27 a directly binded to FOXO1 3′UTR in hippocampal neurons and inhibited FOXO1 expression,suggesting that FOXO1 was the target gene for mi R-27 a.These findings confirm that mi R-27 a protects hippocampal neurons against oxygen-glucose deprivation-induced injuries.The mechanism might be mediated by modulation of FOXO1 and apoptosis-related gene caspase-3 expression.

MicroRNA-219 alleviates glutamate-induced neurotoxicity in cultured hippocampal neurons by targeting calmodulin-dependent protein kinase Ⅱ gamma

Septic encephalopathy is a frequent complication of sepsis,but there are few studies examining the role of micro RNAs（mi Rs） in its pathogenesis.In this study,a mi R-219 mimic was transfected into rat hippocampal neurons to model mi R-219 overexpression.A protective effect of mi R-219 was observed for glutamate-induced neurotoxicity of rat hippocampal neurons,and an underlying mechanism involving calmodulin-dependent protein kinase II γ（Ca MKIIγ） was demonstrated.mi R-219 and Ca MKIIγ m RNA expression induced by glutamate in hippocampal neurons was determined by quantitative real-time reverse transcription-polymerase chain reaction（q RT-PCR）.After neurons were transfected with mi R-219 mimic,effects on cell viability and apoptosis were measured by 3-（4,5-dimethylthiazolyl-2）-2,5-diphenyltetrazolium bromide（MTT） assay and flow cytometry.In addition,a luciferase reporter gene system was used to confirm Ca MKIIγ as a target gene of mi R-219.Western blot assay and rescue experiments were also utilized to detect Ca MKIIγ expression and further verify that mi R-219 in hippocampal neurons exerted its effect through regulation of Ca MKIIγ.MTT assay and q RT-PCR results revealed obvious decreases in cell viability and mi R-219 expression after glutamate stimulation,while Ca MKIIγ m RNA expression was increased.MTT,flow cytometry,and caspase-3 activity assays showed that mi R-219 overexpression could elevate glutamate-induced cell viability,and reduce cell apoptosis and caspase-3 activity.Moreover,luciferase Ca MKIIγ-reporter activity was remarkably decreased by co-transfection with mi R-219 mimic,and the results of a rescue experiment showed that Ca MKIIγ overexpression could reverse the biological effects of mi R-219.Collectively,these findings verify that mi R-219 expression was decreased in glutamate-induced neurons,Ca MKIIγ was a target gene of mi R-219,and mi R-219 alleviated glutamate-induced neuronal excitotoxicity by negatively controlling Ca MKIIγ expression.

The OH Maser Line Receiving System for the Urumqi 25m Radio Telescope

A maser spectral line system is newly implemented on the Urumqi 25m Radio Telescope. The system consists mainly of a cooling receiver and a 4096 channels digital correlation spectrometer. The frequency resolution of the spectrometer at the maximum signal bandwidth of 80MHz is 19.5kHz. After careful calibrations observation at the 1665 MHz OH maser emission was made towards a number of sources, including W49N and W75N. The observed results demonstrate that the digital correlation spectrometer is suitable for astronomical spectral line observations.

CHD1 deletion stabilizes HIF1α to promote angiogenesis and glycolysis in prostate cancer

Chromodomain-helicase-DNA-binding protein 1(CHD1)deletion is among the most common mutations in prostate cancer(PCa),but its role remains unclear.In this study,RNA sequencing was conducted in PCa cells after clustered regularly interspaced palindromic repeat(CRISPR)/CRISPR-associated protein 9(Cas9)-based CHD1 knockout.Gene set enrichment analysis(GSEA)indicated upregulation of hypoxia-related pathways.A subsequent study confirmed that CHD1 deletion significantly upregulated hypoxia-inducible factor 1α(HIF1α)expression.Mechanistic investigation revealed that CHD1 deletion upregulated HIF1αby transcriptionally downregulating prolyl hydroxylase domain protein 2(PHD2),a prolyl hydroxylase catalyzing the hydroxylation of HIF1αand thus promoting its degradation by the E3 ligase von Hippel–Lindau tumor suppressor(VHL).Functional analysis showed that CHD1 deletion promoted angiogenesis and glycolysis,possibly through HIF1αtarget genes.Taken together,these findings indicate that CHD1 deletion enhances HIF1αexpression through PHD2 downregulation and therefore promotes angiogenesis and metabolic reprogramming in PCa.

Aerodynamic performance of distributed electric propulsion with wing interaction

Distributed electric propulsion(DEP)uses multiple propellers driven by motors distributed along the leading edge of the wing to produce beneficial aerodynamic interactions.However,the wing will be in the sliding flow of the propeller and the lift and drag characteristics of the wing will change accordingly.The performance of the propeller will also be affected by the wing in its rear.In this paper,combined with wind tunnel tests,the low Reynolds aerodynamic properties of multiple DEP structures are numerically simulated by solving the Reynolds averaged Navier-Stokes(RANS)equation of multiple reference frames(MRF)or slip grid technology.The results demonstrate that the lift and drag of DEP increase in all cases,with the magnitude depending on the angle of attack(AOA)and the relative positions of propellers and wing.When the AOA is less than 16°(stall AOA),the change of lift is not affected by it.By contrast,when the AOA is greater than 16°the L/D(lift-to-drag ratio)of the DEP system increases significantly.This is because the propeller slipstream delays laminar flow separation and increases the stall AOA.At the same time,the inflow and the downwash effect,which is generated on both sides of the rotating shaft,result in the actual AOA of the wing being greater than the free flow AOA with a fluctuation distribution of the lift coefficient along the span.Also,for the propeller in the DEP,the blocking effect of the wing and the vortex of the trailing edge of the wing result in a significant increase in thrust.

Rationale,design,and baseline characteristics of Chinese registry in early detection and risk stratification of coronary plaques(C-STRAT)study

To the Editor:Coronary computed tomographic angiography(CCTA)has been considered as one of the most important noninvasive imaging modalities in diagnosing coronary artery disease(CAD).[1]Modern scanner of CCTA can provide precise coronary atherosclerotic plaque information,showing improved diagnostic accuracy and sensitivity for identifying obstructive CAD with a preferable temporal and spatial resolution.Several studies have demonstrated the prognosis value of CCTA for the prediction of future adverse CAD events.