Genistein activates endothelial nitric oxide synthase in broiler pulmonary arterial endothelial cells by an Akt-dependent mechanism

Deregulation of endothelial nitric oxide synthase (eNOS) plays an important role in the development of multiple cardiovascular diseases. Our recent study demonstrated that genistein supplementation attenuates pulmonary arterial hypertension in broilers by restoration of endothelial function. In this study, we investigated the molecular mechanism by using broiler pulmonary arterial endothelial cells (PAECs). Our results showed that genistein stimulated a rapid phosphorylation of eNOS at Ser(1179) which was associated with activation of eNOS/NO axis. Further study indicated that the activation of eNOS was not mediated through estrogen receptors or tyrosine kinase inhibition, but via a phosphatidylinositol 3-kinase (PI3K)/Akt-dependent signaling pathway, as the eNOS activity and related NO release were largely abolished by pharmacological inhibitors of PI3K or Akt. Thus, our findings revealed a critical function of Akt in mediating genistein-stimulated eNOS activity in PAECs, partially accounting for the beneficial effects of genistein on the development of cardiovascular diseases observed in animal models.     

Molecular modeling for the interaction between proteasome beta 5 subunit and organotin compounds

It has been reported that organotins can inhibit the proteasomal chymotrypsin-like activity and induce cell death, but the interaction mode of organotins with proteasome has not been well defined. In this study, the IC₅₀ of butyltins and phenyltins against the proteasomal activity and the nature of their inhibition were investigated. It was found that both mono- and di-organotins were weak, reversible inhibitors against the proteasome, while tributyltin and triphenyltin were potent, irreversible proteasome inhibitors. In silico studies using the reversible organotin proteasome inhibitors demonstrated a tight correlation of the estimated proteasomal inhibition constants (Ki) with the experimental IC₅₀ values for proteasome inhibition. Furthermore, the Sn atom in TBT and TPT was found susceptible to form a coordinate bond with Thr 1 O^γ of the β5 subunit, which may account for the irreversible proteasome inhibition. The computational docking approach well predicted the inhibition nature of organotins toward the proteasomal chymotrypsin-like activity. This predictive model might aid in understanding the cytotoxic behavior of similar organometallic compounds.     

Synthesis and antiviral activities of synthetic glutarimide derivatives

A series of novel glutarimide compounds were synthesized and their antiviral activities were evaluated. The compounds displaying the strongest antiviral activities included 5, 6f, 7e and 9 against coxsackievirus B3 (Cox B3), 10 and 6f against influenza virus A (influenza A) and 7a against herpes simplex virus 2 (HSV-2). However, most of the synthetic glutarimides showed comparatively much weaker activity against influenza A, Cox B3 and HSV-2 than the natural glutarimide compounds tested. Based on the results, it seemed likely that a conjugated system at the β-substituted moiety provides stronger antiviral activity.     

多重调和Dirichlet问题奇异正解的对称性

我们在穿孔单位球上研究下面多重调和Dirichlet问题{(-Δ)ku=f(u),在B\{0)内,u＞0,在B\{0)内,u=(e)u/(e)v=…=(e)k-1u/(e)vk-1=0,在(e)B上,其中,B是RN中的单位球,v是(e)B的单位外法向量,N＞2k,k≥2.在f满足适当假设条件下,如果0是不可去奇点,我们...     

Synthesis and Crystal Structure of Two Diflunisal Carboxamides

Graphical abstract  

The title compounds, 2′,4′-difluoro-4-[(4-methylbenzoyl)oxy]-N-[4-nitro-3-(trifluoromethyl)phenyl]-[1,1′-biphenyl]-3-carboxamide 2a and 2′,4′-difluoro-4-[(4-chlorobenzoyl)oxy]-N-[4-nitro-3-(trifluoromethyl) phenyl]-[1,1′-biphenyl]-3-carboxamide 2b, synthesized from diflunisal, a registered anti-inflammatory drug, via amidation of carboxlic acid and esterification of phenolic hydroxy group, were confirmed by single- crystal X-ray diffraction showing their packing are stabilized by intermolecular hydrogen bonds      

溶胶凝胶法制备Ti1-xFexO2纳米颗粒及磁性能研究

采用溶胶凝胶法制备了稀磁半导体Ti1-xFexO2(x=0～0.050)的纳米颗粒,在氩气氛围中以500℃对样品进行退火处理,并通过差热/热重综合热分析仪(TG-DTA)、X射线衍射仪(XRD)、拉曼光谱(Raman)分析了纳米颗粒的结构和相变温度.使用振动样品磁场计(VSM)测试了样品的磁性能.研究发现:经500℃氩...     

BIG6模式下利用废旧设备开发光电实验

废旧设备作为高校的一类固定资产,如何处理好它,尽量发挥其残值,是高校设备管理的一个课题.相当多的废旧设备属于光电类器件,包含各自的光电工作原理,如激光打印机、光电鼠标、光驱等,利用此类废旧设备开发出对应的光电实验,可以作为光信息科学与技术专业的补充实验.开发过程基于BIG6信息问题解决模式,强调师生互动.提高学生的动手...     

Widely ultra-narrow linewidth 104 nm tunable all-fiber compact erbium-doped ring laser

A widely tunable narrow linewidth compact erbium-doped all-fiber ring laser with 104 nm tuning range was reported. An all-fiber Fabry-Perot filter (FFP-TF) was used to realize the laser tuning output, and the wavelength at constant voltage had high time stability. With the 8 m length erbium-doped fiber as gain medium, we realized widely tunable laser from 1513 to 1617 nm with the linewidth less than 40 pm at any wavelength. Pumped by the 976 nm laser diode, the fiber laser worked with slope efficiency of above 10% and threshold of less than 21 mW.     

All-fiber ultra-narrow linewidth 50 pm Tm<Superscript>3+</Superscript>-doped double-clad fiber laser at 1948 nm

A high stability all-fiber LD-clad-pumped Tm³⁺-doped fiber laser was reported. The fiber laser had the ultra-narrow linewidth 50 pm at 1.948 μm with the maximal output power of 12.8 W. The slope efficiency was 28.9%, and threshold was 5.7 W. The double-clad Tm³⁺-doped fiber core was multi-mode, which had a demission of 25/250 μm with the core NA of 0.1 and inner-clad NA of 0.46. The high reflectivity coupler FBG was directly written into the single-mode passive photosensitive optical fiber core, which had a core diameter of 15 μm and NA of 0.1. The cavity was build-up by the high reflectivity FBG and the output fiber end Fresnel reflectivity.     

奇异微分方程的广义Sturm--Liouville边值问题正解的存在性

By employing the fixed point theorem of cone expansion and compression of norm type, we investigate the existence of positive solutions of generalized Sturm-Liouville boundary value problems for a nonlinear singular differential equation with a parameter. Some sufficient conditions for the existence of positive solutions are established. In the last section, an example is presented to illustrate the applications of our main results.