氩气雾化Rene'95合金粉末颗粒二次枝晶间距的研究

本文利用光学显微镜定量金相法测量了氩气雾化Rene’95粉末高温合金粉末颗粒的平均二次枝晶间距,应用牛顿冷却定律得出粉末颗粒的冷却速度,并计算了粉末颗粒完全凝固所需要的时间。在此基础上推导出了Rene’95合金粉末颗粒的二次枝晶间距、颗粒直径以及冷却速度和凝固速度、凝固时间之间的关系。d=0.242D^0.489,d=10.9V^0.488,d=2.47（de/dt）^-0.492,d=39.28tk^0.245。研究结果表明:氩气雾化Rene'95合金粉末颗粒凝固时,满足一般铸造合金时的关系式,即d=av^-n,d=btⁿ,n基本上在1/3～1/2之间。     

低饱和场巨磁电阻金属多层膜Ni80Fe20/Cu的结构与磁电阻

采用磁控溅射方法,获得了具有低饱和场巨磁电阻的Ni₈₀Fe₂0/Cu由金属多层膜.在室温下,其磁电阻和层间耦合状态随Cu层厚度的增加呈振荡变化.在Cu层厚度tcu=1.0nm,2.2nm时磁电阻出现2个峰值分别为19.4%和11.7%,饱和场约为6.4×10⁴ A/m和8×10³ A/m,低温下(77K)磁电阻为对33.2%和27.6%.系统地研究了NiFe层厚度和周期数对多层膜磁电阻的影响.用真空退火方法对样品进行热处理,发现多层膜的磁电阻性能有明显改变.     

The Latest Evidence of Erythropoietin in the Treatment of Glaucoma

Erythropoietin (EPO) is a circulating hormone conventionally considered to be responsible for erythropoiesis. In addition to facilitating red blood cell production, EPO has pluripotent potential, such as for cognition improvement, neurogenesis, and anti-fibrotic, anti-apoptotic, anti-oxidative, and anti-inflammatory effects. In human retinal tissues, EPO receptors (EPORs) are expressed in the photoreceptor cells, retinal pigment epithelium, and retinal ganglion cell layer. Studies have suggested its potential therapeutic effects in many neurodegenerative diseases, including glaucoma. In this review, we discuss the correlation between glaucoma and EPO, physiology and potential neuroprotective function of the EPO/EPOR system, and latest evidence for the treatment of glaucoma with EPO.     

Anp32a Promotes Neuronal Regeneration after Spinal Cord Injury of Zebrafish Embryos

After spinal cord injury (SCI) in mammals, neuronal regeneration is limited; in contrast, such regeneration occurs quickly in zebrafish. Member A of the acidic nuclear phosphoprotein 32 (ANP32a) family is involved in neuronal development, but its function is controversial, and its involvement in zebrafish SCI remains unknown. To determine the role of zebrafish ANP32a in the neuronal regeneration of SCI embryos, we microinjected ANP32a mRNA into embryos from zebrafish transgenic line Tg(mnx1:GFP) prior to SCI. Compared to control SCI embryos, the results showed that the regeneration of spinal cord and resumption of swimming capability were promoted by the overexpression of ANP32a mRNA but reduced by its knockdown. We next combined fluorescence-activated cell sorting with immunochemical staining of anti-GFAP and immunofluorescence staining against anti-PH3 on Tg(gfap:GFP) SCI embryos. The results showed that ANP32a promoted the proliferation and cell number of radial glial cells at the injury epicenter at 24 h post-injury (hpi). Moreover, when we applied BrdU labeling to SCI embryos derived from crossing the Tg(gfap:GFP) and Tg(mnx1:TagRFP) lines, we found that both radial glial cells and motor neurons had proliferated, along with their increased cell numbers in Anp32a-overexpression SCI-embryos. On this basis, we conclude that ANP32a plays a positive role in the regeneration of zebrafish SCI embryos.     

4-Acetylantroquinonol B Suppresses Prostate Cancer Growth and Angiogenesis via a VEGF/PI3K/ERK/mTOR-Dependent Signaling Pathway in Subcutaneous Xenograft and In Vivo Angiogenesis Models

Prostate cancer is a major cause of cancer-related mortality in men in developed countries. The compound, 4-acetylantroquinonol B (4AAQB), is isolated from Antrodia cinnamomea (commonly known as Niu-Chang-Chih), which has been shown to inhibit cancer growth. However, the anticancer activity of 4AAQB has not previously been examined in prostate cancer. This study aimed to investigate the effect of 4AAQB on cancer and angiogenesis, as well as to explore its mechanism of action. Human prostate cancer cells (PC3) and human umbilical vein endothelial cells (HUVEC) were used in cell viability, cell migration, and cell cycle functional assays to evaluate the anticancer and antiangiogenic efficacy of 4AAQB in vitro. The effects of 4AAQB in vivo were determined using xenograft and angiogenesis models. The signaling events downstream of 4AAQB were also examined. The 4AAQB compound inhibited PC3 cell growth and migration, and reduced in vivo cancer growth, as shown in a subcutaneous xenograft model. Furthermore, 4AAQB inhibited HUVEC migration, tube formation, and aortic ring sprouting; it also reduced neovascularization in a Matrigel implant angiogenesis assay in vivo. The 4AAQB compound also decreased metastasis in the PC3 prostate cancer model in vivo. Serum or vascular endothelial growth factor (VEGF)-induced VEGF receptor 2 (VEGFR2), phosphoinositide 3-kinase (PI3K)/Ak strain transforming (Akt), and extracellular signal-regulated kinase ½ (ERK ½) phosphorylation were attenuated by 4AAQB in both PC3 and HUVEC. In conclusion, 4AAQB is a potential candidate for prostate cancer therapy.     

Erythropoietin in Optic Neuropathies: Current Future Strategies for Optic Nerve Protection and Repair

Erythropoietin (EPO) is known as a hormone for erythropoiesis in response to anemia and hypoxia. However, the effect of EPO is not only limited to hematopoietic tissue. Several studies have highlighted the neuroprotective function of EPO in extra-hematopoietic tissues, especially the retina. EPO could interact with its heterodimer receptor (EPOR/βcR) to exert its anti-apoptosis, anti-inflammation and anti-oxidation effects in preventing retinal ganglion cells death through different intracellular signaling pathways. In this review, we summarized the available pre-clinical studies of EPO in treating glaucomatous optic neuropathy, optic neuritis, non-arteritic anterior ischemic optic neuropathy and traumatic optic neuropathy. In addition, we explore the future strategies of EPO for optic nerve protection and repair, including advances in EPO derivates, and EPO deliveries. These strategies will lead to a new chapter in the treatment of optic neuropathy.     

Nitric Oxide Signalling in Descending Vasa Recta after Hypoxia/Re-Oxygenation

Reduced renal medullary oxygen supply is a key factor in the pathogenesis of acute kidney injury (AKI). As the medulla exclusively receives blood through descending vasa recta (DVR), dilating these microvessels after AKI may help in renoprotection by restoring renal medullary blood flow. We stimulated the NO-sGC-cGMP signalling pathway in DVR at three different levels before and after hypoxia/re-oxygenation (H/R). Rat DVR were isolated and perfused under isobaric conditions. The phosphodiesterase 5 (PDE5) inhibitor sildenafil (10⁻⁶ mol/L) impaired cGMP degradation and dilated DVR pre-constricted with angiotensin II (Ang II, 10⁻⁶ mol/L). Dilations by the soluble guanylyl cyclase (sGC) activator BAY 60-2770 as well as the nitric oxide donor sodium nitroprusside (SNP, 10⁻³ mol/L) were equally effective. Hypoxia (0.1% O₂) augmented DVR constriction by Ang II, thus potentially aggravating tissue hypoxia. H/R left DVR unresponsive to sildenafil, yet sGC activation by BAY 60-2770 effectively dilated DVR. Dilation to SNP under H/R is delayed. In conclusion, H/R renders PDE5 inhibition ineffective in dilating the crucial vessels supplying the area at risk for hypoxic damage. Stimulating sGC appears to be the most effective in restoring renal medullary blood flow after H/R and may prove to be the best target for maintaining oxygenation to this vulnerable area of the kidney.     

高效液相色谱-质谱技术在食品安全检测中的应用

本文综述高效液相色谱及其与紫外、质谱检测器在食品安全检测中的应用。详述食品中三聚氰胺、苏丹红、食品添加剂、农药残留量、抗生素药物残留量、毒素的检测等的检测技术。对于保证食品质量、维护人民健康安全有着重要意义。     

闽南红砖传统砌筑工艺及其启示

重点归纳了闽南红砖的传统砌筑工艺类型,在此基础上初步分析其产生背后的社会文化因素和建筑学意义.     

HSPA4 Is a Biomarker of Placenta Accreta and Enhances the Angiogenesis Ability of Vessel Endothelial Cells

Placenta accreta spectrum (PAS) accounts for 7% of maternal mortality and is associated with intraoperative and postoperative morbidity caused by massive blood loss, infection, and adjacent organ damage. The aims of this study were to identify the protein biomarkers of PAS and to further explore their pathogenetic roles in PAS. For this purpose, we collected five placentas from pregnant subjects with PAS complications and another five placentas from normal pregnancy (NP) cases. Then, we enriched protein samples by specifically isolating the trophoblast villous, deeply invading into the uterine muscle layer in the PAS patients. Next, fluorescence-based two-dimensional difference gel electrophoresis (2D-DIGE) and MALDI-TOF/MS were used to identify the proteins differentially abundant between PAS and NP placenta tissues. As a result, nineteen spots were determined as differentially abundant proteins, ten and nine of which were more abundant in PAS and NP placenta tissues, respectively. Then, specific validation with western blot assay and immunohisto/cytochemistry (IHC) assay confirmed that heat shock 70 kDa protein 4 (HSPA4) and chorionic somatomammotropin hormone (CSH) were PAS protein biomarkers. Further tube formation assays demonstrated that HSPA4 promoted the in vitro angiogenesis ability of vessel endothelial cells, which is consistent with the in vivo scenario of PAS complications. In this study, we not only identified PAS protein biomarkers but also connected the promoted angiogenesis with placenta invasion, investigating the pathogenetic mechanism of PAS.