Betamethasone Dipropionate Loaded in Nanoliposomes vs Conventional Betamethasone Dipropionate: Comparative Study of Permeability and Penetrability in Vitro and ex Vivo

A betamethasone dipropionate (BD) liposomal cream was developed to treat rheumatological, inflammatory, allergic diseases and psoriasis. BD is a corticosteroid, anti-inflammatory, and immunosuppressant. However, adverse effects are associated with prolonged topical use. For this reason, liposomes were loaded with BD because they offer excellent biocompatibility, bio adhesiveness, and penetrability that improve the effects caused by the conventional drug. Liposomal dispersions were prepared by emulsification using phospholipid 90 (lipid) and Tween 80 (surfactant). The particle size, polydispersity index (PDI), and zeta potential were measured using a particle analyzer. The betamethasone (BM) percentage of encapsulated active (EA) ingredient was also determined through High Performance Liquid Chromatography (HPLC). The Franz cell and tape stripping characterized these in vitro and ex vivo. Then the final formulation reached a particle size of 70.80 ± 3.31 nm, a PDI of 0.242 ± 0.038, a zeta potential of −11.68 ± 0.77 mv and encapsulate active of 83.1% ± 2.4, complying with the parameters of a nanotechnological formulation. In vitro and ex vivo studies confirmed significantly efficacy of the cream over the commercial product, through the greater penetration into the pig ear skin, resulting in an improved drug. Finally, the liposomal cream demonstrated significant potential for enhanced percutaneous absorption, attributed to its nanometric size. This innovative nanotechnology approach aims to reduce the frequency of topical applications, thereby minimizing the side effects associated with psoriasis treatment.

工程教育中心何以推动科教融合——荷兰4TU工程教育中心的探索性单案例研究

工程教育中心作为建立在大学或研究机构中的跨学科交叉合作平台,是连接科学研究与教育实践的纽带,在高质量工程人才培养中发挥着重要作用。荷兰4TU工程教育中心利用4所顶尖理工大学在工程学科和教育领域的独特优势,积极与研发单位、教育单位、企业部门合作,通过将前沿科学研究彻底融入工程课程设计、教学模式等多个方面,形成了独具一格的科教融合工程人才培养模式。文章从战略目标、组织架构、运行机制、质量保障4个维度详实分析了4TU工程教育中心推动科教融合的内在机制,总结归纳其在主题项目设置、教育共同体形成、课程体系迭代、创新网络构建、内外部质量保障等方面的核心特征,期望对我国科教融合的工程教育改革与建设有所启示。

沉默TUFM通过AMPK/mTOR信号通路调控线粒体自噬对肺源性心脏病模型大鼠肺动脉高压的影响

目的探讨线粒体翻译延伸因子Tu(TUFM)通过线粒体自噬促进肺动脉高压(PAH)血管重塑的作用机制。方法2022年1月—2023年6月于辽宁省人民医院中心实验室进行实验。将36只健康雄性Sprague-Dawley大鼠随机分为空白对照(Ctrl)组、模型(PAH)组、TUFM过表达(OE)组、OE阴性对照(OE-NC)组、短发夹RNA(Sh)敲除TUFM(Sh)组和Sh-NC阴性对照(Sh-NC)组,每组6只。除Ctrl组外,其余大鼠均一次性腹腔注射1%野百合碱(60 mg/kg)诱导心源性肺水肿PAH大鼠模型;大鼠肺动脉平滑肌细胞(PASMC)在低氧(3%O 2)条件下培养24 h模拟体内肺动脉高压微环境,分为常氧(Norm)组、低氧(Hyp)组、小干扰RNA(SiRNA)-1组、SiRNA-2组、Si-NC组、OE-NC组和OE组。右心导管插管和脉冲多普勒超声检测大鼠肺血流动力学;苏木素-伊红染色检测肺小动脉病理结构;免疫荧光共染检测TUFM组织定位;细胞计数法检测细胞增殖;透射电镜观察线粒体结构和自噬小体;蛋白免疫印迹检测TUFM、自噬、凋亡和磷酸腺苷活化蛋白激酶(AMPK)/哺乳动物雷帕霉素靶蛋白(mTOR)通路相关蛋白表达。结果与Ctrl组比较,PAH组大鼠TUFM蛋白表达升高,且主要与PASMC标志物α平滑肌肌动蛋白(α-SMA)在肺小动脉内膜存在共定位,而与内皮细胞标志物CD31无共定位,肺动脉收缩压(PASP)升高,肺动脉血流加速时间(PAAT)缩短,远端肺小动脉管壁呈向心性增厚,管腔狭窄几乎堵塞,TUFM、苄氯素1重组蛋白(BECN1)、人微管相关蛋白轻链3(LC3)II/I和B淋巴细胞瘤2(Bcl2)蛋白表达升高,P62、Bcl2相关X蛋白(Bax)和凋亡酶激活因子(Apaf)蛋白表达降低(P<0.05);与PAH组比较,OE组PASP升高,PAAT缩短,肺小动脉管壁厚度升高,肺动脉TUFM、BECN1、LC3II/I和Bcl2表达升高,P62、Bax和Apaf表达降低(P<0.05);与PAH组比较,Sh组PASP降低,PAAT延长,肺小动脉管壁厚度和管腔狭窄度有所改善,TUFM、BECN1、LC3II/I和Bcl2表达降低,P62、Bax和Apaf表达升高(P<0.05)。与Norm组比较,Hyp组PASMC细胞TUFM蛋白表达升高;与Si-NC组细胞相比,SiRNA-1和SiRNA-2组P62、Bax蛋白表达升高,BECN1、LC3II/I、Bcl2、TUFM表达降低,线粒体结构完整,PASMC细胞增殖活性降低,细胞p-AMPK表达降低,p-mTOR表达升高(P<0.05);与OE-NC组比较,OE组细胞P62和Bax蛋白表达降低,BECN1、LC3II/I、Bcl2和TUFM表达升高,部分线粒体损伤崩解,嵴断裂消失,PASMC细胞增殖活性明显升高,细胞p-AMPK表达升高,p-mTOR表达降低(P<0.05)。结论沉默TUFM可通过激活AMPK/mTOR信号通路促进线粒体自噬加速PAH肺动脉平滑肌细胞凋亡。

秦川牛宰后成熟过程中线粒体翻译延长因子Tu与能量代谢的关联性分析

目的:线粒体翻译延长因子Tu(mitochondrial Tu translation elongation factor,TUFM)已被证明参与秦川牛宰后成熟过程中的细胞自噬活动,实验探究该过程中TUFM表达与能量代谢变化的关系。方法:以秦川牛背最长肌为研究对象,测定4℃不同成熟时间(0、2、12、24、48、96、144、192 h)TUFM表达量及含量、葡萄糖(glucose,GLU)、乳酸(lactic acid,LA)、腺苷三磷酸(adenosine triphosphate,ATP)、二磷酸腺苷(adenosine diphosphate,ADP)、单磷酸腺苷(adenosine monophosphate,AMP)6种物质含量以及乳酸脱氢酶(lactate dehydrogenase,LDH)、琥珀酸脱氢酶(succinate dehydrogenase,SDH)、磷酸丙糖异构酶(triose phosphate isomerase,TPI)、苹果酸脱氢酶(malate dehydrogenase,MDH)、细胞色素c氧化酶(cytochrome c oxidase,COX)5种酶活性的变化情况。结果:在秦川牛宰后成熟期间,GLU、ATP、ADP、AMP含量和LDH、SDH、TPI活性均呈下降趋势,TUFM表达量、MDH活性及LA和TUFM含量均呈先上升后下降趋势,COX活性呈先下降后上升再下降趋势。能量代谢各指标和TUFM蛋白主要在宰后初期发挥作用,对宰后初期及宰后中后期分别进行Pearson相关性分析,结果表明,在宰后初期牛背最长肌中TUFM表达量与MDH、LA呈极显著正相关(P<0.01),与ATP、ADP、AMP、LDH、SDH、TPI、COX、GLU呈极显著负相关(P<0.01)。在宰后中后期,TUFM表达与所有指标(GLU、LA、ATP、ADP、AMP、LDH、MDH、SDH、TPI、COX)均呈极显著正相关(P<0.01)。结论:在宰后初期TUFM表达量逐渐增加,可为肌肉细胞提供能量从而用于能量代谢途径,该过程可能是TUFM正向参与细胞自噬所致。在宰后中后期能量短缺时,TUFM可能抑制细胞自噬,优先将能量用于除细胞自噬外的其他重要途径(如能量代谢途径)以维持细胞稳态。综上,在宰后成熟过程中TUFM具有双重作用,可调节细胞自噬为能量代途径提供能量,有助于维持宰后能量代谢持续的时间。

绵羊肺炎支原体EF-Tu蛋白的原核表达及多克隆抗体制备

[目的]克隆绵羊肺炎支原体(Mycoplasma ovipneumoniae,Mo)EF-Tu基因,原核表达获得EF-Tu蛋白,制备抗EF-Tu蛋白的兔源多克隆抗体,为研究肺炎支原体EF-Tu蛋白的结构和功能奠定基础。[方法]采用重叠延伸PCR方法将pET-28a-EF-Tu质粒中EF-Tu基因中间的TGA密码子突变为TGG,并对测序结果与其他支原体参考株进行相似性比对和遗传进化分析,利用在线软件对其推测的蛋白序列进行生物信息学分析。将突变后的重组质粒转化大肠杆菌BL21(DE3)感受态细胞进行原核表达,经SDS-PAGE和Western blotting鉴定,利用镍柱亲和层析法纯化,以纯化的EF-Tu融合蛋白免疫家兔制备多克隆抗体,采用间接ELISA和Western blotting检测多克隆抗体效价及免疫反应性。[结果]试验成功突变了EF-Tu基因中TGA位点,并构建了融合表达His标签pET-28a-EF-Tu′原核表达载体。生物信息学分析表明,克隆的EF-Tu基因与绵羊肺炎支原体MoGH3-3菌株相似性最高,亲缘关系最近;编码387个氨基酸,无N-糖基化位点和跨膜区域,存在10个丝氨酸、20个苏氨酸、4个酪氨酸磷酸化位点,二级结构由无规则卷曲(35.14%)、α-螺旋(26.87%)、延伸链(26.87%)及β-转角(11.11%)构成。SDS-PAGE和Western blotting结果显示,目的蛋白大小约为43 ku,蛋白纯化浓度为0.615 g/L。ELISA和Western blotting结果显示,制备的多克隆抗体效价可达1∶128 000,能够特异性识别EF-Tu融合蛋白,具有良好的免疫反应性。[结论]本研究成功突变了EF-Tu基因的TGA密码子,原核表达并纯化获得EF-Tu融合蛋白,制备其多克隆抗体效价为1∶128 000,为后续研究肺炎支原体EF-Tu蛋白结构和生物学功能及其疫苗研发提供了试验基础。

异氟烷麻醉对小鼠自发肌电及TUS/TMAS诱发肌电的影响

经颅超声刺激(TUS)和经颅磁声耦合刺激(TMAS)调控运动皮层效果明显,但受限于清醒状态动物难以束缚,已有研究大多在麻醉状态下进行,对麻醉减弱调控效果的分析集中于中枢神经系统。本研究记录了异氟烷麻醉下24只小鼠的肢体自发肌电和TUS/TMAS诱发肌电,定量分析了麻醉对自发肌电和诱发肌电发放率、潜伏期、时长和幅值的影响。结果显示,随着异氟烷输出浓度从0.40%增加至0.75%,每周期内小鼠自发肌电频次减少约50%,肌电发放时长变短,呈抑制状态;TUS/TMAS诱发肌电的成功率分别降低约50%和70%、潜伏期均延长约0.1 s、时长分别缩短约0.3和0.5 s,表明TUS/TMAS对运动皮层的调控效果随麻醉程度的加深而减弱。肢体自发和诱发肌电在发放率和时长上存在关联性特征,提示麻醉状态下小鼠自发肌电抑制状态可能是刺激效果减弱的影响因素之一。

An Investigation of Moxibustion Treatment for Abscesses in the Song Dynasty:Focusing on the“Jiu Ai Tu”

Jiu Ai Tu(The Moxa Treatment)from the Song dynasty is the earliest surviving painting that focuses on the subject of acupuncture and moxibustion.This paper takes the medical activities depicted in the artwork as its research object and systematically analyzes the external treatment methods for abscesses during the Song dynasty reflected in Jiu Ai Tu.By examining the understanding of abscesses during that period,the paper explores the level of development in external medicine techniques.By analyzing the medical awareness and behaviors of patients when facing such severe illnesses,it aims to explore the societal cognition and experiences regarding health and disease.The paper attempts to present the folk medical ecology of the Song dynasty represented by Jiu Ai Tu.

The water-soluble TF3 component from Eupolyphaga sinensis Walker promotes tibial fracture healing in rats by promoting osteoblast proliferation and angiogenesis

Objective:To determine the active components of Eupolyphaga sinensis Walker(Tu Bie Chong)and explore the mechanisms underlying its fracture-healing ability.Methods: A modified Einhorn method was used to develop a rat tibial fracture model.Progression of bone healing was assessed using radiological methods.Safranin O/fast green and CD31 immunohistochemical staining were performed to evaluate the growth of bone cells and angiogenesis at the fracture site.Methylthiazoletetrazolium blue and wound healing assays were used to analyze cell viability and migration.The Transwell assay was used to explore the invasion capacity of the cells.Tubule formation assays were used to assess the angiogenesis capacity of human vascular endothelial cells(HUVECs).qRT-PCR was used to evaluate the changes in gene transcription levels.Results: Tu Bie Chong fraction 3(TF3)significantly shortened the fracture healing time in model rats.X-ray results showed that on day 14,fracture healing in the TF3 treatment group was significantly better than that in the control group(P=.0086).Tissue staining showed that cartilage growth and the number of H-shaped blood vessels at the fracture site of the TF3 treatment group were better than those of the control group.In vitro,TF3 significantly promoted the proliferation and wound healing of MC3T3-E1s and HUVECs(all P<.01).Transwell assays showed that TF3 promoted the migration of HUVECs,but inhibited the migration of MC3T3-E1 cells.Tubule formation experiments confirmed that TF3 markedly promoted the ability of vascular endothelial cells to form microtubules.Gene expression analysis revealed that TF3 significantly promoted the expression of VEGFA,SPOCD1,NGF,and NGFR in HUVECs.In MC3T3-E1 cells,the transcript levels of RUNX2 and COL2A1 were significantly elevated following TF3 treatment.Conclusion: TF3 promotes fracture healing by promoting bone regeneration associated with the RUNX2 pathway and angiogenesis associated with the VEGFA pathway.

Development of a topical ointment of betamethasone dipropionate loaded nanostructured lipid carrier

The purpose of this study was to design an innovative topical ointment containing betamethasone dipropionate loaded nanostructured lipid carrier (BD-NLC) for the treatment of atopic dermatitis (AD). BD-loaded NLC was produced with precirol ATO 5 and oleic oil (OA) by melt emulsification method. Effects of surfactant concentration, amount of solid lipid and liquid lipid on skin retention and skin penetration were investigated by in vitro percutaneous permeation experiment. The optimized BD-NLC showed a homogeneous particle size of 169.1 nm (with PI = 0.195), negatively charged surface (-23.4 mV) and high encapsulation efficiency (85%). Particle morphology assessed by TEM revealed a spherical shape. In vitro skin permeation study was carried out to investigate the percutaneous behaviors of W/O ointment with BD-NLC and Carbopol emulgel ointment with BD-NLC. W/O ointment with BDNLC showed high skin retention (35.43 μg/g) and low penetration (0.87 μg/ml). In vitro drug release studies were carried out to demonstrate the drug releasing properties of the two ointments. W/O ointment with BD-NLC showed an advantage for skin retention as it was better for drug release. The tissue distribution test suggested that BD distribution was skin > muscle > blood. Self-made topical ointment in mice showed no skin irritation. The animal experiments indicated that BD-loaded NLC ointment was effective and safe for topical use.

TU1无氧铜/316L不锈钢电子束焊接接头组织与性能

采用真空电子束焊分别对2mm、3mm、5mm不同厚度的TU1无氧铜板材和316L不锈钢板材进行异种材料焊接,并对焊接接头的显微组织和力学性能进行了研究。实验结果表明:焊缝区和热影响区呈现波浪形状,焊缝区存在不同程度的混合组织,接头母材区及热影响区的晶粒大小随铜钢板材厚度的增加而增加。TU1热影响区的晶粒明相比母材区,明显增大。焊缝区的硬度高于母材区。在电子束电流为10mA,加速电压为150kV,焊接速度为15mm/s的焊接参数下,2mm、3mm、5mm厚的接头抗拉强度分别是263MPa、174MPa、141MPa。2mm厚的拉伸式样断裂发生在TU1热影响区,而3mm和5mm厚拉伸式样断裂发生在焊缝处,即2mm厚的TU1无氧铜板材和316L不锈钢板材焊接接头抗拉性能最好。

Anastomotic stoma coated with chitosan film as a betamethasone dipropionate carrier for peripheral nerve regeneration

Scar hyperplasia at the suture site is an important reason for hindering the repair effect of peripheral nerve injury anastomosis. To address this issue, two repair methods are often used. Biological agents are used to block nerve sutures and the surrounding tissue to achieve phys- ical anti-adhesion effects. Another agent is glucocorticosteroid, which can prevent scar growth by inhibiting inflammation. However, the overall effect of promoting regeneration of the injured nerve is not satisfactory. In this regard, we envision that these two methods can be combined and lead to shared understanding for achieving improved nerve repair. In this study, the right tibial nerve was transected 1 cm above the knee to establish a rat tibial nerve injury model. The incision was directly sutured after nerve transection. The anastomotic stoma was coated with 0.5 × 0.5 cm^2 chitosan sheets with betamethasone dipropionate. At 12 weeks after injury, compared with the con- trol and poly （D, L-lactic acid） groups, chitosan-betamethasone dipropionate film slowly degraded with the shape of the membrane still intact. Further, scar hyperplasia and the degree of adhesion at anastomotic stoma were obviously reduced, while the regenerated nerve fiber structure was complete and arranged in a good order in model rats. Electrophysiological study showed enhanced compound muscle action potential. Our results confirm that chitosan-betamethasone dipropionate film can effectively prevent local scar hyperplasia after tibial nerve repair and promote nerve regeneration.

Impact of Prophylactic Betamethasone Indication on the Neonatal Outcome in 38-Week Pregnancies Prior to Elective Cesarean Section

Objective: To assess whether the use of prenatal betamethasone in pregnancies with elective Caesarean section (C-section) at 38 weeks has a similar risk of adverse neonatal respiratory outcomes than elective C-section at 39 weeks. Methods: Retrospective cohort study of pregnant patients with singleton pregnancies and elective C-section at term in a one-year period. Cases were C-section at 38 weeks of gestation with a complete course of betamethasone started 48-hours before. As a control group, pregnancies with a C-section at 39 weeks without betamethasone were included. Results: During the study period, 186 patients were included. Of these, 91 were delivered at 38 weeks and 95 at 39 weeks. There were no significant differences in maternal age and parity. Moreover, there were no significant differences in respiratory complications (respiratory distress syndrome [RDS] = 0% vs 1.1%;p = 1.0, transitory tachypnea [TT] = 0% vs 0%) and admission to Neonatal Intensive Care Unit (NICU) (8.8% vs 6.3%;p = 0.7) between deliveries at 38 weeks and 39 weeks, respectively. Conclusion: Prophylactic use of betamethasone in early term pregnancies who undergo an elective C-section at 38 weeks is associated with similar adverse neonatal respiratory outcomes than patients with C-section at 39 weeks without corticosteroids.

Efficacy and safety of low dose compound betamethasone in the treatment of mild knee osteoarthritis

Objective:To investigate the efficacy and safety of intra-articular injection of low-dose compound betamethasone in the treatment of mild knee osteoarthritis.Methods:From September 2018 to December 2019,90 patients with mild knee osteoarthritis were divided into complete dose group and low dose group according to the treatment sequence,45 cases in each group.The complete dose group was treated with intra-artiular injection of betamethasone(1ml)and sodium hyaluronate(2ml),once a week,three times as a course of treatment.The low dose group was treated with intra-artiular injection of betamethasone(0.3ml)and sodium hyaluronate(2ml),once a week,three times as a course of treatment.Lysholm scores、the Western Ontario and McMaster Universities Osteoarthritis Index(WOMAC)and visual analogue scale(VAS)were compared between the two groups before and after treatment,and the efficacy and safety of the two groups were evaluated.Results:80 patients were followed up with an average of(4.96±1.50)months ranging from 3 to 8 months,and 10 cases(11.11%)were dropped out,including 2 cases in the complete dose group,2 cases in the midway withdrawal group,and 1 case in the treatment course less than the treatment course;3 cases in the low dose group lost the follow-up,and 2 cases dropped out.Compared with that before treatment,Lysholm scores were significantly improved,WOMAC scores and VAS scores were significantly decreased in the two groups at 3 weeks,6 weeks and 12 weeks after treatment(P<0.001).The Lysholm scores of low dose group were78.10±2.16,86.78±2.55,80.90±2.26,WOMAC scores were 61.00±1.38,39.03±1.98,45.76±1.66 and VAS scores were 2.23±0.89,0.78±0.73 and 1.05±0.85 in low dose group at 3 weeks,6 weeks and 12 weeks after treatment.There was no significant difference between the two groups(P>0.05).No drugrelated adverse reactions occurred in both groups.Conclusion:The curative effect of low dose compound betamethasone intra-articular injection in the treatment of mild knee osteoarthritis is equivalent to that of complete dose compound betamethasone.It can improve the function and symptoms of knee joint,and is safe and effective.

延伸因子Tu GTP结合域蛋白2功能研究进展

延伸因子Tu GTP结合域蛋白2(elongation factor Tu GTP binding domain containing protein,EFTUD2)是剪接体复合物U5小核糖核蛋白的核心组件,通过调节剪接体的剪接功能进而调控相关基因的表达。本文旨在总结EFTUD2在免疫调节、胚胎发育和肿瘤进展等方面的重要作用。

New Photometric Investigations of G-type Contact Binary TU Boo

Two sets of CCD photometric observations for contact binary TU Boo were obtained in 2020 and 2021.Different from its asymmetric light curves published from the literature,our BVRcIc-band curves show that the heights of maximum are almost equal.These distortions of light curves possibly indicate that the components were active in past 25 yr,but they were stable in the last two years.For total-eclipse binary TU Boo,due to some star-spots on the surface of the components,the physical structure obtained by many investigators are different.Therefore,the symmetric multi-color light curves in 2020,2021 are important for understanding configuration and evolution of this system.By using the Wilson–Devinney program,it is confirmed that TU Boo is an A-type shallow-contact binary with the temperature difference ofΔT=152 K and fill-out of f=14.67%.In the O−C diagram of orbital period analysis,a cyclic oscillation superimposed on a continuous decrease was determined.The long-term decreasing is often explained by the mass transfer from the more massive star to less massive one,this system will evolve into a deeper contact binary with time.The cyclic oscillations computed from much more CCD times of light minimum maybe result from the light-travel time effect via the presence of a third body.These characters of structure,evolution and ternary belong to typical A-type W UMa binaries with spectral G.

河北赤城话“VP+tu■^(53)”结构

河北赤城话中“VP+tu■^(53)”结构表示未然、假设等语义,在对VP的选择上,动作动词、存现动词、趋向动词、能愿动词可以进入此结构,动宾短语、状中短语、动补短语、连动短语可以进入此结构,自主性动词和非自主性动词都可以进入,动态形容词也可以进入此结构。“VP+tu■^(53)”结构主要有VP+tu■^(53)、VO+tu■^(53)、V+tu■^(53)+O、VC+tu■^(53)、VC+O+tu■^(53)等格式类型。“VP+tu■^(53)”结构在时体意义上有将要开始、将要完成等表示未然的意义,在语义上表示条件关系和假设关系。与“的时候”相比,“VP+tu■^(53)”结构语法位置自由度高,语义内涵较为狭窄,在语言使用上存在代际差异。

miR-216b-5p对喉癌TU686细胞增殖、迁移和侵袭的影响及其机制

目的:探讨miR-216b-5p对喉鳞状细胞癌(LSCC)TU686细胞增殖、迁移、侵袭和凋亡的影响,分析其在喉癌细胞中的靶基因及其可能的作用机制。方法:TU686细胞分为对照组和miR-216b-5p组,对照组细胞通过慢病毒感染无义序列,miR-216b-5p组细胞通过慢病毒感染过表达miR-216b-5p。采用实时荧光定量PCR(RT-qPCR)法检测2组细胞中miR-216b-5p表达水平,克隆形成实验检测2组细胞克隆形成率,细胞划痕实验检测2组细胞划痕愈合率,Transwell实验检测2组细胞中侵袭细胞数,流式细胞术检测2组细胞凋亡率。通过TargetScan网站预测miR-216b-5p的潜在靶基因,采用RT-qPCR法检测靶基因mRNA表达水平,双荧光素酶报告基因实验检测miR-216b-5p与靶基因间的靶向关系。结果:慢病毒感染后,与对照组比较,miR-216b-5p组细胞中miR-216b-5p表达水平明显升高(P<0.01)。与对照组比较,miR-216b-5p组细胞克隆形成率和划痕愈合率明显降低(P<0.01),侵袭细胞数明显减少(P<0.01),细胞凋亡率明显升高(P<0.01)。TargetScan网站预测,自噬相关基因5(ATG5)为miR-216b-5p潜在的靶基因,与对照组比较,miR-216b-5p组细胞中ATG5 mRNA表达水平明显降低(P<0.01)。双荧光素酶报告基因实验证实ATG5与miR-216b-5p之间存在靶向关系。结论:miR-216b-5p通过抑制喉癌细胞的增殖、迁移、侵袭和诱导细胞凋亡进而发挥抑癌作用,其机制可能与靶向调节ATG5的表达水平有关。

Eftud2对星形胶质细胞炎症的作用研究

背景创伤性脑损伤后异常激活的神经炎症是预后不良的主要原因之一,星形胶质细胞在炎症发展中具有促进修复或加重损伤的双重作用。延长因子Tu GTP结合域蛋白2(elongation factor Tu GTP binding domain containing protein,Eftud2)是免疫调节因子,在炎症和肿瘤的发生发展中均具重要作用。目的观察Eftud2对星形胶质细胞炎症的影响。方法小鼠随机分为假手术组和创伤性脑损伤组,使用经典控制性皮质撞击装置构建创伤性脑损伤模型。免疫荧光观察损伤前后S100β和Eftud2含量变化。转棒和平衡木实验评估小鼠造模前后运动功能的改变。实时荧光定量PCR检测损伤前后组织中IL-1β、TNF-α、NLRP3转录水平变化。使用小干扰RNA敲低小鼠星形胶质细胞(mouse astrocyte,MA)中的Eftud2,而后使用脂多糖刺激MA细胞系模拟炎性状态,实时荧光定量PCR检测MA细胞中IL-6、IL-1β、TNF-α、GM-CSF、CXCL-10、IL-10、MyD88转录水平变化,蛋白质免疫印迹检测MA细胞中Eftud2和MyD88的蛋白表达变化。结果动物实验中,与假手术组相比,创伤性脑损伤组小鼠损伤部位Eftud2和S100β荧光强度增加(P<0.01),损伤组织周围炎性因子IL-1β、TNF-α、NLRP3转录水平升高(P<0.01)。细胞实验中,用脂多糖刺激后,MA细胞中Eftud2蛋白表达水平上调(P<0.05),同时Eftud2转录水平和单细胞荧光强度也升高(P<0.01)。给予小干扰RNA后,敲低组MA细胞中Eftud2蛋白表达水平、转录水平和单细胞荧光强度均显著下降(P<0.01)。敲低MA细胞中的Eftud2并给予脂多糖刺激后,实时荧光定量PCR结果显示,IL-6转录水平下降(P<0.05),IL-1β、TNF-α、GM-CSF、MyD88和CXCL-10转录水平也下降(P<0.01),抗炎因子IL-10转录水平升高(P<0.05)。蛋白免疫印迹结果显示,MyD88蛋白表达水平下降(P<0.05)。结论Eftud2可能通过MyD88介导的信号通路调控星形胶质细胞的炎症反应,其作用机制有待进一步研究。

超高效液相色谱-串联质谱法快速测定动物组织中地塞米松与倍他米松药物残留

在承担糖皮质激素风险监测任务时,发现2个现行有效的关于检测动物组织中糖皮质激素的国家标准(农业部1031号公告-2—2008《动物源性食品中糖皮质激素类药物多残留检测液相色谱-串联质谱法》和GB/T 21981—2008《动物源食品中激素多残留检测方法液相色谱-质谱/质谱法》)中的样品前处理均采用了固相萃取方法,从而导致了检测过程中过柱净化烦琐、氮吹浓缩时间长、检测成本高、生态环境不友好等诸多弊端。在经过大量实验研究及经实际工作应用检验的基础上,研究简化了动物组织中地塞米松和倍他米松残留检测中样品前处理固相萃取过柱和氮吹过程,建立了快速、准确、灵敏的动物组织(牛肝、牛肉、猪肝与猪肉)中残留的地塞米松和倍他米松的超高效液相色谱-串联质谱的同时检测方法。样品在盐析条件下经乙腈提取,正己烷脱脂,采用电喷雾多反应监测、负离子模式测定,对动物组织中地塞米松和倍他米松进行定性和定量。地塞米松和倍他米松的检出限可达0.5μg/kg,定量限可达1.0μg/kg。在地塞米松和倍他米松的质量浓度为0.1~50.0μg/L,峰强度与质量浓度的线性关系良好(R 2>0.99)。在地塞米松和倍他米松的1.0、2.0、5.0μg/kg添加浓度下,方法的平均回收率在83.3%~98.2%。希望该研究可为实验室大批量检测此类药物在动物组织中的残留提供一定的借鉴。

不同厚度的316L/TU1异种材料焊接性能的有限元数值模拟分析

为分析不同厚度的316L/TU1异种材料的焊接性能,利用双椭球体热源与高斯面热源的复合热源模型,分别对2 mm、3 mm、5 mm3种不同厚度的316L/TU1铜钢薄板真空电子束焊接进行了数值模拟研究,获得了其电子束焊接温度场与应力场的分布特征,并进行了试验验证。结果表明,模拟获得的熔池形貌与实际熔池形貌基本一致,验证了所建立的热源模型在计算电子束焊缝形貌特征中的可行性。