Resting-state brain activity in adult males who stutter

Although developmental stuttering has been extensively studied with structural and task-based functional magnetic resonance imaging (fMRI), few studies have focused on resting-state brain activity in this disorder. We investigated resting-state brain activity of stuttering subjects by analyzing the amplitude of low-frequency fluctuation (ALFF), region of interest (ROI)-based functional connectivity (FC) and independent component analysis (ICA)-based FC. Forty-four adult males with developmental stuttering and 46 age-matched fluent male controls were scanned using resting-state fMRI. ALFF, ROI-based FCs and ICA-based FCs were compared between male stuttering subjects and fluent controls in a voxel-wise manner. Compared with fluent controls, stuttering subjects showed increased ALFF in left brain areas related to speech motor and auditory functions and bilateral prefrontal cortices related to cognitive control. However, stuttering subjects showed decreased ALFF in the left posterior language reception area and bilateral non-speech motor areas. ROI-based FC analysis revealed decreased FC between the posterior language area involved in the perception and decoding of sensory information and anterior brain area involved in the initiation of speech motor function, as well as increased FC within anterior or posterior speech- and language-associated areas and between the prefrontal areas and default-mode network (DMN) in stuttering subjects. ICA showed that stuttering subjects had decreased FC in the DMN and increased FC in the sensorimotor network. Our findings support the concept that stuttering subjects have deficits in multiple functional systems (motor, language, auditory and DMN) and in the connections between them.     

Bt基因甜菜叶绿体转化载体构建及毒蛋白表达

利用植物叶绿体基因组在进化中高度保守的特点,根据烟草、菠菜、水稻叶绿体基因组全序列资料设计合成引物,PCR扩增并克隆了甜菜叶绿体两个重要功能基因rbcL和atpB(GenBank登录号分别为DQ067450和DQ067451),并以其作为定点整合外源基因的同源重组片段,构建了Bt基因CryIAc甜菜叶绿体定点转化载体pSKARBt,酶切鉴定表明:所构建载体符合预期设计。对克隆菌菌体总蛋白进行了生物杀虫试验,结果表明:Bt基因CryIAc能够在叶绿体特异性启动子及终止子的调控下表达,并对二龄末甘蓝夜蛾有很强的毒杀作用。该载体构建对培育甜菜高抗虫品种具有重要应用价值。叶绿体转化及后续工作正在进行中。     

Gamma‐amino butyric acid and the A‐type receptor suppress decidualization of mouse uterine stromal cells by down‐regulating cyclin D3

Uterine decidualization, characterized by stromal cell proliferation and differentiation into polyploid decidual cells, is critical to the establishment of pregnancy in mice, although the mechanism underlying this process remains poorly understood. This study is the first to investigate the expression of gamma‐amino butyric acid (GABA) and the GABA A‐type receptor π subunit (GABPR) in the early‐pregnancy mouse uterus and their roles in decidualization. The expression of GABRP was detected from Day 4 to 8 of pregnancy. The effects of GABA and GABA A‐type receptor on cell proliferation and apoptosis were investigated using the Cell Titer 96® AQueous One Solution Cell Proliferation Assay and flow cytometry. The levels of cyclin D3 protein were measured in cultured stromal cells artificially induced to undergo decidualization, and treated with GABA and a GABA A‐type receptor agonist or antagonist, respectively, at the same time. mRNA expression of gabrp in implantation sites was lower than that in inter‐implanted sites. GABA and GABRP protein were localized in the luminal and glandular epithelium, stromal cells, and decidual cells. In vitro, GABPR protein level was decreased in cultured stromal cells during the decidualization process. The addition of GABA and the GABA A‐type receptor agonist Muscimol inhibited stromal cell proliferation, promoted apoptosis, and arrested cells in S‐phase, followed by decreased expression of cyclin D3. These results show that in mice, GABA was actively involved in inhibiting stromal cell proliferation and suppresses decidualization progress through GABA A‐type receptors by down‐regulating cyclin D3 level. Mol. Reprod. Dev. 80: 59–69, 2013. © 2012 Wiley Periodicals, Inc.     

Thermodynamic-based computational profiling of cellular regulatory control in hepatocyte metabolism

Thermodynamic-based constraints on biochemical fluxes and concentrations are applied in concert with mass balance of fluxes in glycogenesis and glycogenolysis in a model of hepatic cell metabolism. Constraint-based modeling methods that facilitate predictions of reactant concentrations, reaction potentials, and enzyme activities are introduced to identify putative regulatory and control sites in biological networks by computing the minimal control scheme necessary to switch between metabolic modes. Computational predictions of control sites in glycogenic and glycogenolytic operational modes in the hepatocyte network compare favorably with known regulatory mechanisms. The developed hepatic metabolic model is used to computationally analyze the impairment of glucose production in von Gierke's and Hers' diseases, two metabolic diseases impacting glycogen metabolism. The computational methodology introduced here can be generalized to identify downstream targets of agonists, to systematically probe possible drug targets, and to predict the effects of specific inhibitors (or activators) on integrated network function.     

北京地区油菜软腐病病原菌的鉴定

摘要:【目的】确定引发北京地区油菜［Brassica campestris L．ssp．chinensis (L.) Makino var． communis Tsen et Lee］软腐病的病原。【方法】结合病原菌形态、BIOLOG 及生理生化、16S rＲNA 基因序列及亚种IGS区特征分析,对从北京大兴和通州区油菜软腐病样中病原菌进行生物学鉴定。【结果】分离的40 个菌株均能引发 油菜软腐病,但分别为胡萝卜果胶杆菌(Pectobacterium carotovorum) 的2个不同亚种,其中13株为P．carotovorum subsp．carotovorum(Pcc),另27株为P．arotovorum subsp． brasiliensis(Pcb)。接种白菜(Brassica campestris L．ssp．pekinensis)致病力测定分析表明,亚种内、来源相同与16S rRNA基因序列相同的菌株间均存在明显的致病力分化。【结论】Pectobacterium carotovorum subsp．carotovorum和Pectobacterium carotovorum subsp. brasiliensis是引发北京地区油菜软腐病的致病菌,后者为首次报道能引起白菜类蔬菜软腐病的常见致病菌。     

柯萨奇病毒A组9型的基因分型方法的建立

血清型别鉴定及基因分型分析是开展肠道病毒（Enterovirus,EV）分子进化特征研究的重要内容。目前为止,国内外对柯萨奇病毒A组9型（Coxsackievirus A9,CVA9）的研究主要集中在衣壳蛋白区的细胞受体结合位点及其基因特性分析,而基于全长VP1序列的基因型划分结果尚未明确。本研究依托国家手足口病监测网络,对2010-2019年全国31个省级行政区（省、自治区、直辖市）上送的18 238份手足口病样本中分离出的24株CVA9进行全长VP1区序列测定,并与GenBank中所有全长VP1区序列一起进行基因型划分研究。测序结果显示24株CVA9分离株VP1全长为906bp,编码302个氨基酸,与CVA9原型株（Griggs）核苷酸和氨基酸相似性分别为80.5%～97.6%和92.3%～99.6%。结合系统进化树和同一血清型内不同基因型的核苷酸差异界值为15%～25%,将全球CVA9划分为A-H八个基因型。进化树显示B、C和D基因型在病毒进化过程中已消失,而E、F和G基因型呈现共循环的趋势,其中G基因型包含了亚洲、北美洲、大洋洲和欧洲等9个国家的毒株,是CVA9的优势基因型。大...     

DNA聚合酶iota在HEK-293细胞中高表达体系的建立

目的:将带有DNA聚合酶iota(DNA Polymerase iota,Polι)目的基因的真核表达质粒PCDNA3.1转入HEK-293细胞,建立DNA聚合酶iota在HEK-293细胞中的高表达体系,为进一步研究DNA聚合酶在DNA损伤修复中的生物学功能奠定了基础.方法:用脂质体2000(Lipofectamine2000)将带有目的基因的真核表达质粒PCDNA3.1转入HEK-293细胞,通过G418筛选抗性克隆,用一步法提取细胞总RNA,采用逆转录聚合酶链式反应(RT-PCR)技术检测出高表达克隆.结果:通过G418筛选筛选出了具有G418抗性的克隆,通过RT-PCR技术检测出高表达DNA聚合酶iota的HEK-293细胞系.结论:建立了高表达DNA聚合酶iota的HEK-293细胞系.为进一步研究DNA聚合酶在DNA损伤修复中的生物学功能奠定了基础.     

Response Characteristics between Sulfate-Reducing Bacteria and Environmental Factors in Petroleum Hydrocarbon-Contaminated Field of Northeast China

Lithology samples were collected from six sites of a petroleum hydrocarbon-contaminated site in northeast China along a contamination plume. The sulfate-reducing bacteria (SRB) diversity of all samples was analyzed by PCR-DGGE technology. The Shannon-Wiener indexes (1.004–3.665), Simpson indexes (0.516–0.907) and Pielou indexes (0.996–1.004) of all samples were used to characterize the abundances, advantages and evenness of the microbial communities. Additionally, Canoco for Windows 4.5 was utilized to analyze the correlation between dominant SRB and environmental factors. The results showed that the abundance, advantages and evenness of the sulfate-reducing bacterial community changed regularly along the contamination plume direction. The microbial homology of the samples was not high (0.25–0.80), and the dominant bacteria exhibited heteroplasmy. Additionally, the dominant bacteria were identified as uncultured bacteria. Canonical correspondence analysis (CCA) analysis showed that the distribution and structure of SRB communities were not obviously correlated with the concentration of total petroleum hydrocarbons (TPH), dissolved oxygen (DO) and other environmental factors. The results presented herein provide evidence of natural bioremediation in petroleum hydrocarbon-contaminated fields and information that will be useful to bioremediation of other contaminated fields.     

急性心肌梗死患者冠脉介入治疗后血浆apelin的变化及作用

目的:观察急性心肌梗死(AMI)患者围手术期血浆apelin的表达变化,分析AMI合并2型糖尿病(T2DM)患者血浆apelin的表达与预后的相关性,探讨apelin在冠脉介入治疗(PCI)中的心脏保护作用。方法:72例于2012年2月~8月在我院心内科接受冠状动脉造影确诊为AMI并成功完成PCI的冠心病患者,分别在术前、术后0小时、术后4小时、术后24小时收集血清,酶联免疫吸附法测定血浆apelin-13水平;进一步对糖尿病及非糖尿病AMI患者(每组各20例)进行亚组分析,随访两组患者在术后6个月时主要不良心脑血管事件(MACCE)。结果:AMI患者术后0 h组apelin水平与术前基线水平明显降低(31.54±5.48 vs35.15±6.48 ng/L,P0.05);术后4小时及24小时组apelin水平较术前明显升高(39.65±5.48 vs 35.15±6.48 ng/L,43.93±5.37 vs35.15±6.48 ng/L,P0.05)。糖尿病与非糖尿病组apelin水平术前无明显差异;糖尿病组在术后各时间点的apelin水平均明显高于非糖尿病组(31.12±5.50 vs 29.21±6.53 ng/L,40.57±5.37 vs 33.49±3.89 ng/L,43.50±7.41 vs 34.54±3.52 ng/L,P0.05)。两组术后6个月随访T2DM组LVEF值改善明显高于NT2DM组,但MACCE事件无明显差异。结论:AMI患者PCI术后存在血浆apelin表达的升高,其中糖尿病患者在术后血浆apelin表达较非糖尿病患者明显增高,提示PCI冠脉血运重建可促进糖尿病患者apelin分泌,调节胰岛素抵抗改善预后。     

生物体内甜菜碱脂的研究进展

甜菜碱脂是一类极性膜脂,自然界中发现的有3类,分布于不同类别的生物中,其中最广泛分布于藻类以及部分低等植物中,有着多种功能,最主要的作用是作为膜脂参与生物的生命活动,对光合作用、植物抗逆以及藻类生物燃料的开发具有重要意义。不同生物体中的甜菜碱脂类别、含量以及分布均有差异,对甜菜碱脂的结构、化学鉴定、细胞内定位、理化性质、生物合成及其分子生物学机理等多方面进行综述,并指出目前研究中仍需解决的问题、可以拓展的方向,以便于对甜菜碱脂进行更为深入地研究。