How dopamine tunes parvalbumin interneurons in the hippocampus:new experimental observations in Alzheimer's disease

Despite decades of dedicated resea rch,Alzheimer's disease (AD) is an age-related and progressive neurodegenerative disorder for which the mechanisms of onset are sti unc ear.AD is cha racterized by featured histological alterations including amyloid-beta (AB) plaque deposition,accumulation of neurofibrillary to ngles of hyperphosphorylated-tau,and neuronal loss,accompanied by progressive cognitive decline and behavioral changes.

Dopamine improves apple replant disease resistance by regulating physiological resilience and rhizosphere microbial community structure

Apple replant disease(ARD)is a complex agricultural problem caused by multiple stressors that can lead to increased reactive oxygen species(ROS)levels and limited nutrient utilization in plants.However,existing countermeasures cannot effectively address this challenge.Here,we used Malus hupehensis as a test organism to investigate whether the pleiotropic molecule dopamine can alleviate ARD using pot experiments.Exogenous application of 100μmol L-1 dopamine significantly promoted the growth of apple seedlings in the replanted soil,with a relative growth rate increase of 17.44%.Our results revealed two major pathways by which dopamine regulates ARD resistance in apple trees.First,dopamine effectively reduces the level of ROS and activates the expression of genes related to nitrogen(N)transport and metabolism.Among those genes,MdNLP5,MdNRT1.1,MdNLP2,MdNRT2.5,MdNLP3,MdNRT2.4,MdNADH-GAGOT,and MdFd-GAGOT were strongly regulated by dopamine.These regulatory effects promoted the uptake and utilization of soil N by the plants.Second,dopamine improved the physical and chemical properties,enhanced microbial community diversity,and promoted mutual cooperation between microbial communities in the soil.Furthermore,dopamine altered the microbial structure of rhizosphere soil(upregulating Clostridiales,Gaiellales,Sordariales and Mortierellales;downregulating Micrococcales,Longimicrobiales,Hypocreales and Cystobasidiales).Notably,dopamine significantly upregulated the abundances of Gaiella and Mortierella,both of which were positively correlated with soil urease activity,soil available N content,plant growth and N uptake.Dopamine also significantly downregulated the abundance of the plant pathogen Gibberella(by 11.71-fold)in replant soil.Our results provide insights into the mechanisms by which dopamine promotes ARD resistance,and can promote the sustainable development of the apple industry.

Dopamine in the prefrontal cortex plays multiple roles in the executive function of patients with Parkinson's disease

Parkinson’s disease can affect not only motor functions but also cognitive abilities,leading to cognitive impairment.One common issue in Parkinson’s disease with cognitive dysfunction is the difficulty in executive functioning.Executive functions help us plan,organize,and control our actions based on our goals.The brain area responsible for executive functions is called the prefrontal co rtex.It acts as the command center for the brain,especially when it comes to regulating executive functions.The role of the prefrontal cortex in cognitive processes is influenced by a chemical messenger called dopamine.However,little is known about how dopamine affects the cognitive functions of patients with Parkinson’s disease.In this article,the authors review the latest research on this topic.They start by looking at how the dopaminergic syste m,is alte red in Parkinson’s disease with executive dysfunction.Then,they explore how these changes in dopamine impact the synaptic structure,electrical activity,and connection components of the prefrontal cortex.The authors also summarize the relationship between Parkinson’s disease and dopamine-related cognitive issues.This information may offer valuable insights and directions for further research and improvement in the clinical treatment of cognitive impairment in Parkinson’s disease.

Hippocampal dopamine as a key regulator for learning deficits in Parkinson's disease

Parkinson's disease(PD)is a progressive neurodegenerative disorder with clinical symptoms of involuntary or uncontrollable movements such as tremors,rigidity,and incoordination.The learning deficit is largely overlooked in the past because it is generally less impaired in the early stages of PD than in Alzheimer's disease.

Melatonin and dopamine alleviate waterlogging stress in apples by recruiting beneficial endophytes to enhance physiological resilience

Melatonin and dopamine can potentially prevent waterlogging stress in apples.The current study investigated the mechanism by which melatonin and dopamine alleviate apple waterlogging stress.This study demonstrated that melatonin and dopamine alleviated waterlogging by removing reactive oxygen species(ROS),and that the nitric oxide(NO)content and nitrate reductase(NR)activity were significantly correlated.Melatonin and dopamine were also found to recruit different candidate beneficial endophytes(melatonin:Novosphingobium,Propionivibrio,and Cellvibrio;dopamine:Hydrogenophaga,Simplicispira,Methyloversatilis,Candidatus_Kaiserbacteria,and Humicola),and these endophytes were significantly and positively correlated with plant growth.Network analyses showed that melatonin and dopamine significantly affected the endophytic bacterial and fungal communities under waterlogging stress.The metabolomic results showed that melatonin and dopamine led to waterlogging resistance by upregulating the abundance of beneficial substances such as amino acids,flavonoids,coumarins,and organic acids.In addition,melatonin and dopamine regulated the physicochemical properties of the soil,which altered the endophyte community and affected plant growth.The co-occurrence network demonstrated close and complex relationships among endophytes,metabolites,soil,and the plants.Our results demonstrate that melatonin and dopamine alleviate waterlogging stress in apples by recruiting beneficial endophytes to enhance physiological resilience.This study provides new insights into how melatonin and dopamine alleviate stress and a theoretical basis for synergistic beneficial microbial resistance to waterlogging stress.

The dopaminergic system and Alzheimer's disease

Alzheimer's disease is a common neurodegenerative disorder in older adults.Despite its prevalence,its pathogenesis remains unclea r.In addition to the most widely accepted causes,which in clude excessive amyloid-beta aggregation,tau hyperphosphorylation,and deficiency of the neurotransmitter acetylcholine,numerous studies have shown that the dopaminergic system is also closely associated with the occurrence and development of this condition.Dopamine is a crucial catecholaminergic neurotransmitter in the human body.Dopamine-associated treatments,such as drugs that target dopamine receptor D and dopamine analogs,can improve cognitive function and alleviate psychiatric symptoms as well as ameliorate other clinical manifestations.Howeve r,therapeutics targeting the dopaminergic system are associated with various adverse reactions,such as addiction and exacerbation of cognitive impairment.This review summarizes the role of the dopaminergic system in the pathology of Alzheimer's disease,focusing on currently available dopamine-based therapies for this disorder and the common side effects associated with dopamine-related drugs.The aim of this review is to provide insights into the potential connections between the dopaminergic system and Alzheimer's disease,thus helping to clarify the mechanisms underlying the condition and exploring more effective therapeutic options.

Mussel-inspired Methacrylic Gelatin-dopamine/Ag Nanoparticles/Graphene Oxide Hydrogels with Improved Adhesive and Antibacterial Properties for Applications as Wound Dressings

A novel strategy was developed to prepare the methacrylic gelatin-dopamine(GelMA-DA)/Ag nanoparticles(NPs)/graphene oxide(GO) composite hydrogels with good biocompatibility,mechanical properties,and antibacterial activity.Mussel-inspired DA was utilized to modify the GelMA molecules,which imparts good adhesive performance to the hydrogels.GO,interfacial enhancer,not only improves mechanical properties of the hydrogels,but also provides anchor sites for loading Ag NPs through numerous oxygencontaining functional groups on the surface.The experimental results show that the GelMA/Ag NPs/GO hydrogels have good biocompatibility,and exhibit a swelling rate of 202±16%,the lap shear strength of 147±17 kPa,and compressive modulus of 136±53 kPa,in the case of the Ag NPs/GO content of 2 mg/mL.Antibacterial activity of the hydrogels against both gram-negative and gram-positive bacteria is dependent on the Ag NPs/GO content derived from the release of Ag^(+).Furthermore,the GelMA/Ag NPs/GO hydrogels possess good adhesive ability,which is resistant to highly twisted state when stuck on the surface of pigskin.These results demonstrate promising potential of the GelMA-DA/Ag NPs/GO hydrogels as wound dressings for biomedical applications in clinical and emergent treatment.

Regulatory mechanisms of dopamine metabolism in a marine Meyerozyma guilliermondii GXDK6 under NaCl stress as revealed by integrative multi-omics analysis

Dopamine can be used to treat depression,myocardial infarction,and other diseases.However,few reports are available on the de novo microbial synthesis of dopamine from low-cost substrate.In this study,integrated omics technology was used to explore the dopamine metabolism of a novel marine multi-stress-tolerant aromatic yeast Meyerozyma guilliermondii GXDK6.GXDK6 was found to have the ability to biosynthesize dopamine when using glucose as the substrate.14 key genes for the biosynthesis of dopamine were identified by whole genome-wide analysis.Transcriptomic and proteomic data showed that the expression levels of gene AAT2 encoding aspartate aminotransferase(regulating dopamine anabolism)were upregulated,while gene AO-I encoding copper amine oxidase(involved in dopamine catabolism)were downregulated under 10%NaCl stress compared with non-NaCl stress,thereby contributing to biosynthesis of dopamine.Further,the amount of dopamine under 10%NaCl stress was 2.51-fold higher than that of zero NaCl,which was consistent with the multi-omics results.Real-time fluorescence quantitative PCR(RT-qPCR)and high-performance liquid chromatography(HPLC)results confirmed the metabolic model of dopamine.Furthermore,by overexpressing AAT2,AST enzyme activity was increased by 24.89%,the expression of genes related to dopamine metabolism was enhanced,and dopamine production was increased by 56.36%in recombinant GXDK6AAT2.In conclusion,Meyerozyma guilliermondii GXDK6 could utilize low-cost carbon source to synthesize dopamine,and NaCl stress promoted the biosynthesis of dopamine.

In vitro polymerization of the dopamine-borate melanin precursor:A proof-of-concept regarding^(10)boron neutron-capture therapy for melanoma

The^(10)boron neutron-capture therapy(BNCT)is an emerging antitumoral method that shows increasing biomedical interest.BNCT is based on the selective accumulation of the^(10)boron isotope within the tumor,which is then irradiated with low-energy thermal neutrons,generating nuclear fission that produces 7lithium,4helium,andγrays.Simple catechol-borate esters have been rather overlooked as precursors of melanin biosynthesis,and therefore,a proof-of-concept approach for using dopamine-borate(DABO)as a suitable boron-containing candidate for potential BNCT is presented here.DABO can spontaneously oxidize and autopolymerize in vitro,giving a soluble,eumelaninlike brown-black poly-DABO product.Melanotic melanoma cell cultures treated with 1 mM DABO for 24 and 48 h were viable and showed no signs of damage or cell death.The stability and possible trans-esterification of DABO is shortly discussed.Chemical calculations and quantitative structure-activity relationships(QSAR)analysis of DABO and the BNCT agent BPA indicated that they should be cell permeant and accumulate within lysosomes and melanosomes.Molecular modeling allows visualization of both the DABO precursor and the structure of a borate derivative of the proposed catechol-porphycene model for eumelanin,showing interesting features from molecular orbital calculations.The main difference between DABO and other agents,such as BPA,is that it is not a boronic acid nor a boron cluster.This simple catechol-borate ester(protected from oxidation and blackening)could be administrated to living cells and organisms,in which biosynthesis of boron-melanin in melanoma melanocytes can lead to improved BNCT.

Cortico-striatal gamma oscillations are modulated by dopamine D3 receptors in dyskinetic rats

Long-term levodopa administration can lead to the development of levodopa-induced dyskinesia.Gamma oscillations are a widely recognized hallmark of abnormal neural electrical activity in levodopa-induced dyskinesia.Currently,studies have reported increased oscillation power in cases of levodopa-induced dyskinesia.However,little is known about how the other electrophysiological parameters of gamma oscillations are altered in levodopa-induced dyskinesia.Furthermore,the role of the dopamine D3 receptor,which is implicated in levodopa-induced dyskinesia,in movement disorder-related changes in neural oscillations is unclear.We found that the cortico-striatal functional connectivity of beta oscillations was enhanced in a model of Parkinson’s disease.Furthermore,levodopa application enhanced cortical gamma oscillations in cortico-striatal projections and cortical gamma aperiodic components,as well as bidirectional primary motor cortex(M1)↔dorsolateral striatum gamma flow.Administration of PD128907(a selective dopamine D3 receptor agonist)induced dyskinesia and excessive gamma oscillations with a bidirectional M1↔dorsolateral striatum flow.However,administration of PG01037(a selective dopamine D3 receptor antagonist)attenuated dyskinesia,suppressed gamma oscillations and cortical gamma aperiodic components,and decreased gamma causality in the M1→dorsolateral striatum direction.These findings suggest that the dopamine D3 receptor plays a role in dyskinesia-related oscillatory activity,and that it has potential as a therapeutic target for levodopa-induced dyskinesia.

Recent progress in the applications of presynaptic dopaminergic positron emission tomography imaging in parkinsonism

Nowadays,presynaptic dopaminergic positron emission tomography,which assesses deficiencies in dopamine synthesis,storage,and transport,is widely utilized for early diagnosis and differential diagnosis of parkinsonism.This review provides a comprehensive summary of the latest developments in the application of presynaptic dopaminergic positron emission tomography imaging in disorders that manifest parkinsonism.We conducted a thorough literature search using reputable databases such as PubMed and Web of Science.Selection criteria involved identifying peer-reviewed articles published within the last 5 years,with emphasis on their relevance to clinical applications.The findings from these studies highlight that presynaptic dopaminergic positron emission tomography has demonstrated potential not only in diagnosing and differentiating various Parkinsonian conditions but also in assessing disease severity and predicting prognosis.Moreover,when employed in conjunction with other imaging modalities and advanced analytical methods,presynaptic dopaminergic positron emission tomography has been validated as a reliable in vivo biomarker.This validation extends to screening and exploring potential neuropathological mechanisms associated with dopaminergic depletion.In summary,the insights gained from interpreting these studies are crucial for enhancing the effectiveness of preclinical investigations and clinical trials,ultimately advancing toward the goals of neuroregeneration in parkinsonian disorders.

EFFECTS OF DOPAMINE,ESTRADIOL AND TESTOSTERONE ON GONADOTROPIN RELEASE FROM THE PITUITARY FRAGMENTS OF Rana rugulosa

To understand the regulatory mechanisms of gonadotropin secretion in Rana rugulosa ,this study investigated the effects of dopamine (DA),estradiol (E 2) and testosterone (T) on the in vitro release of luteinizing hormone (LH) and follicle stimulating hormone (FSH) from the pituitary fragments of female Rana rugulosa using a static incubation system and radio immunoassay (RIA). The results indicated that DA at the concentration from 0 1?μmol/L to 10?μmol/L inhibited the release of LH and FSH from the pituitary fragments of sexually pre mature or hibernating individuals,and the inhibitory effects enhanced with increasing concentrations of DA. E 2 at 1?μmol/L and 10?μmol/L significantly stimulated the release of LH of sexually pre mature individuals,but inhibited their FSH release at 0 1?μmol/L to 10?μmol/L;T had no obvious effects on their FSH release,but significantly inhibited their LH release at 10?μmol/L. Neither E 2 nor T,at the concentration from 0 1?μmol/L to 100?μmol/L,had obvious effects on the release of LH and FSH of hibernating individuals. The data suggest that DA and sexual steroids may have direct regulatory actions on LH and FSH release at the pituitary level in Rana rugulosa ,and the action of sexual steroids may relate to the gonadal development stages (seasons).

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。

Effects of endogenous dopamine induced by low concentration atropine eye drops on choroidal neovascularization in high myopia mice

AIM:To evaluate effects of endogenous dopamine induced by low concentration atropine eye drops on choroidal neovascularization(CNV)in high myopia mice.METHODS:The C57BL/6J mice were deprived of the right eye for 4wk,and the high myopia was diagnosed by optometry,the diopter was less than-6.00 D,and CNV was induced by 532 nm laser.The changes of dopamine D1 receptor(DRD1),dopamine D2 receptor(DRD2),and vascular endothelial growth factor A(VEGFA)were detected by Western blot technology at 0.5,1,2h,and 7d after 0.01%,0.05%,and 0.1%atropine eye drops,respectively,the area of CNV was measured.RESULTS:Significant increases were observed on the expression of DRD2 in mouse high myopia model at 0.5,1,2h,7d with 0.05%and 0.1%atropine eye drops(P<0.05).Significant decreases were observed on the expression of DRD1 and VEGFA in mouse high myopia model at 0.5,1,2h,7d with 0.05%and 0.1%atropine eye drops(P<0.05).The area of CNV induced by laser in the drug-treated group was significantly smaller than that in the control group,and the higher the concentration,the more significant the inhibitory effect(P<0.05).CONCLUSION:The 0.01%,0.05%,0.1%atropine eye drops can decrease the level of VEGFA and inhibit high myopia CNV indirectly by up-regulating the level of DRD2 and down-regulating the level of DRD1,and the effect of 0.05%and 0.1%atropine eye drops is more significant.

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。

Blunt dopamine transmission due to decreased GDNF in the PFC evokes cognitive impairment in Parkinson’s disease

Studies have found that the absence of glial cell line-derived neurotrophic factor may be the primary risk factor for Parkinson’s disease. However, there have not been any studies conducted on the potential relationship between glial cell line-derived neurotrophic factor and cognitive performance in Parkinson’s disease. We first performed a retrospective case-control study at the Affiliated Hospital of Xuzhou Medical University between September 2018 and January 2020 and found that a decreased serum level of glial cell line-derived neurotrophic factor was a risk factor for cognitive disorders in patients with Parkinson’s disease. We then established a mouse model of Parkinson’s disease induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine and analyzed the potential relationships among glial cell line-derived neurotrophic factor in the prefrontal cortex, dopamine transmission, and cognitive function. Our results showed that decreased glial cell line-derived neurotrophic factor in the prefrontal cortex weakened dopamine release and transmission by upregulating the presynaptic membrane expression of the dopamine transporter, which led to the loss and primitivization of dendritic spines of pyramidal neurons and cognitive impairment. In addition, magnetic resonance imaging data showed that the long-term lack of glial cell line-derived neurotrophic factor reduced the connectivity between the prefrontal cortex and other brain regions, and exogenous glial cell line-derived neurotrophic factor significantly improved this connectivity. These findings suggested that decreased glial cell line-derived neurotrophic factor in the prefrontal cortex leads to neuroplastic degeneration at the level of synaptic connections and circuits, which results in cognitive impairment in patients with Parkinson’s disease.

A Multiwall Carbon Nanotube-chitosan Modified Electrode for Selective Detection of Dopamine in the Presence of Ascorbic Acid

A novel multiwall carbon nanotube-chitosan modified electrode has been prepared.The modified electrode resolves the overlapping voltammetric response of dopamine and ascorbicacid into two well-defined peak by 212 mV. The mechanism of discrimination of dopamine fromascorbic acid is discussed. Dopamine can be determined selectively with the carbonnanotube-chitosan modified electrode. The electrode shows good sensitivity, selectivity andstability.

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。