椎管内注射牛肾上腺髓质22肽差异性翻转吗啡耐受作用

牛肾上腺髓质22肽（bovine adrenal medulla22,BAM22）是脑啡肽原A的一种降解产物,与阿片受体和感觉神经元特异性受体（sensory neuron-specific receptor,SNSR）均有亲合力。本研究的目的是探讨BAM22对吗啡耐受的影响。连续7d对大鼠椎管内注射20μg吗啡形成吗啡耐受后,分为吗啡组、盐水组和BAM22组,第8天三组大鼠椎管内分别注射吗啡、生理盐水和BAM22,第9天三组大鼠椎管内均注射吗啡后,运用撤足反射、福尔马林实验和免疫组织化学等方法观察吗啡的作用效果。结果显示：在撤足反射实验中,BAM22组的吗啡能延长撤足反射潜伏期最大可能作用的48．5％,并持续约1h：在福尔马林实验中,BAM22组的吗啡能分别缩短福尔马林引起的第一期和第二期疼痛行为变化3．2min和24min,比盐水组分别减少45％和82％（P〈0．05,P〈0．001）;此外,在免疫组织化学实验中,BAM22组的吗啡能显著减少热刺激引起的脊髓背角c-Fos蛋白表达,其Ⅰ-Ⅱ层、Ⅲ-Ⅳ层和Ⅴ-Ⅵ层均减少约80％（P〈0．001）。本研究从整体和细胞水平表明,BAM22能翻转吗啡的耐受,这种作用在持续性疼痛模型中的表现要比急性痛中更为明显,显示BAM22对吗啡耐受的差异性调制;同时也提示感觉神经元特异性受体可能参与吗啡耐受的调制。     

A new scaphognathid pterosaur from western Liaoning,China

A partial skeleton of a new pterosaur, Jianchangnathus robustus gen. et sp. nov. from western Liaoning, China, is described. The specimen (IVPP V16866) was collected near Linglongta, Jianchang County, whose deposits have a disputed age that range from Middle Jurassic to Early Cretaceous. The new species shares several features with the non-pterodactyloid Scaphognathus from the Late Jurassic deposits of southern Germany, such as a deep anterior end of the lower jaw, a piriform lower temporal fenestra with the ventral margin broader than the dorsal one and the interalveolar spacing of the maxillary teeth about three alveolar spaces, allowing its allocation to the Scaphognathidae. The main diagnostic features of J. robustus include the large maxillary process of the jugal, the convex alveolar margin of the lower jaw and the procumbent disposition of the first three pairs of dentary teeth. The new Chinese taxon also differs from Fenghuangopterus lii, which comes from the same deposit and is here regarded as Scaphognathidae incertae sedis, mainly by the lower number of teeth and several proportions of the wing elements. The discovery of J. robustus demonstrates a larger diversity in the pterosaur fauna of the Linglongta region so far dominated by the non-pterodactyloid clade Wukongopteridae.     

浙江天童常绿阔叶林中11种常绿乔灌木叶片虫食状分析

为探讨昆虫对植物叶片的取食行为和伤害方式,作者选择浙江天童常绿阔叶林内的11种常绿乔灌木为对象,对叶片虫食状类型和格局进行分析。结果如下:(1)共发现16种虫食状类型,每种植物叶片虫食状类型数在10–13种之间,每种虫食状出现频率在0.5–28.7%之间。缘食状出现频率最高(28.7%),虫瘿和泡状出现频率最低(0.5%)。(2)叶片虫食状分布格局可分为3种类型,即一种虫食状占绝对优势的单优格局,如马银花(Rhododendronovatum)和檵木(Loropetalumchinense);两种虫食状(缘食状和顶食状)共占优势的双优格局,仅有木荷(Schimasu-perba);3种及3种以上虫食状占优势的多优格局(其余8种植物)。(3)叶片虫食状多样性指数变化在1.57–2.23之间,最高为苦槠(Castanopsissclerophylla),最低为马银花;乔木的多样性指数(2.040)高于灌木(1.882),优势种多样性指数高于伴生种,但差异均不显著;多样性指数反映了虫食状类型和出现频率的综合差异。(4)16种虫食状类型中有8对显著正相关,4对显著负相关,可能反映出不同类型昆虫取食植物的趋同和差异。     

Recurrent Seasonal Variations in Abundance and Composition of Filamentous SOL Cluster Bacteria (Saprospiraceae, Bacteroidetes) in Oligomesotrophic Lake Mondsee (Austria)

The spatial and temporal variation of SOL cluster bacteria was assessed in oligomesotrophic Lake Mondsee and adjacent lakes by fluorescence in situ hybridization over two annual cycles. The filamentous SOL bacteria were present in Lake Mondsee throughout the study period, and the seasonal dynamics of the SOL community were remarkably similar with respect to both abundance and composition in the two consecutive years. Only two of the three SOL subclusters were detected in Lake Mondsee and four connected lakes. These two populations significantly differed in size distribution and demonstrated pronounced but recurrent differences in seasonality and length of period of appearance in Lake Mondsee. Extensive sampling of the lakes in September 2003 revealed low horizontal variation in the composition of the SOL community within Lake Mondsee but marked variations with depth. Between connected habitats pronounced differences in the composition and abundance of the SOL community were detected. The interaction of SOL bacteria with bacterivorous protists, mesozooplankton, and phytoplankton was investigated in order to reveal variables controlling the structure and dynamics of SOL communities. No strong indication for a bottom-up influence of phytoplankton was found, while the estimated community grazing rates of mesozooplankton on SOL bacteria indicated a top-down control of SOL abundance during mesozooplankton peaks in spring and early autumn. Furthermore, species-specific differences in grazing of mesozooplankton on SOL bacteria were observed. In general, the overall composition of SOL communities was controlled by abiotic factors (water chemistry), while their dynamics seemed to be controlled by abiotic and biotic interactions.     

Interactions between bovine serum albumin and gemini surfactant alkanediyl-alpha, omega-bis(dimethyldodecyl-ammonium bromide)

Interactions between bovine serum albumin (BSA) and cationic gemini surfactant alkanediyl-alpha,omega-bis(dimethyldodecyl-ammonium bromide) (12-n-12, n=3, 4, 6) in aqueous solution have been investigated by measuring fluorescence, UV-vis transmittance, dynamic lighting scattering, and circular dichroism. Compared to a traditional surfactant dodecyltrimethylammonium bromide (DTAB), 12-n-12 interacts with BSA more strongly. With increasing concentration, 12-n-12 first binds specifically onto BSA leading to the unfolding and aggregation of BSA, and the decrease in alpha-helix content; and then forms micelle-like complexes along the unfolded BSA chains. A gemini surfactant with a longer spacer has a larger effect on BSA unfolding due to a stronger hydrophobic interaction.     

Novel role for K+-dependent Na+/Ca2+ exchangers in regulation of cytoplasmic free Ca2+ and contractility in arterial smooth muscle

Cytoplasmic free Ca2+ ([Ca2+]cyt) is essential for the contraction and relaxation of blood vessels. The role of plasma membrane Na+/Ca2+ exchange (NCX) activity in the regulation of vascular Ca2+ homeostasis was previously ascribed to the NCX1 protein. However, recent studies suggest that a relatively newly discovered K+-dependent Na+/Ca2+ exchanger, NCKX (gene family SLC24), is also present in vascular smooth muscle. The purpose of the present study was to identify the expression and function of NCKX in arteries. mRNA encoding NCKX3 and NCKX4 was demonstrated by RT-PCR and Northern blot in both rat mesenteric and aortic smooth muscle. NCXK3 and NCKX4 proteins were also demonstrated by immunoblot and immunofluorescence. After voltage-gated Ca2+ channels, store-operated Ca2+ channels, and Na+ pump were pharmacologically blocked, when the extracellular Na+ was replaced with Li+ (0 Na+) to induce reverse mode (Ca2+ entry) activity of Na+/Ca2+ exchangers, a large increase in [Ca2+]cyt signal was observed in primary cultured aortic smooth muscle cells. About one-half of this [Ca2+]cyt signal depended on the extracellular K+. In addition, after the activity of NCX was inhibited by KB-R7943, Na+ replacement-induced Ca2+ entry was absolutely dependent on extracellular K+. In arterial rings denuded of endothelium, a significant fraction of the phenylephrine-induced and nifedipine-resistant aortic or mesenteric contraction could be prevented by removal of extracellular K+. Taken together, these data provide strong evidence for the expression of NCKX proteins in the vascular smooth muscle and their novel role in mediating agonist-stimulated [Ca2+]cyt and thereby vascular tone.     

美登木根的显微结构及其内生真菌的分布

本文采用石蜡永久制片和光学显微摄像的方法对美登木(Maytenus confertiflorus)根的显微结构及其内生真菌的分布进行了研究。结果表明, 美登木根的次生结构由周皮和维管组织构成; 周皮由木栓层、木栓形成层和栓内层组成, 其中木栓层由5～6 列长形细胞组成; 维管组织中次生韧皮部所占根径的比例达46%, 其薄壁细胞中内含物较丰富, 次生木质部中分布有导管和木射线及少量木薄壁组织; 在美登木木栓层和次生韧皮部中分布有菌丝片段、膨大的菌丝、菌丝团及分生孢子; 内生真菌只在一定区域的皮层和次生韧皮部细胞中分布。     

Design and synthesis of 7H-pyrrolo[2,3-d]pyrimidines as focal adhesion kinase inhibitors. Part 1

A series of 2-amino-9-aryl-7H-pyrrolo[2,3-d]pyrimidines were designed and synthesized to target focal adhesion kinase (FAK). A number of these pyrrolopyrimides exhibited low micromolar inhibitory activities against focal adhesion kinase, and their preliminary SAR was established via systematic chemical modifications. The 2-amino-9-aryl-7H-pyrrolo[2,3-d]pyrimidines represent a new class of kinase inhibitors.     

Valproate-Induced Epigenetic Upregulation of Hypothalamic Fto Expression Potentially Linked with Weight Gain

Cellular and Molecular Neurobiology - Valproate (VPA), a widely-used antiepileptic drug, is a selective inhibitor of histone deacetylase (HDAC) that play important roles in epigenetic regulation....     

人成体心源间充质样细胞表型分析及向心脏谱系诱导分化潜能的研究

目的探讨成人心源性间充质样细胞 (CDMCs)的分子表型及向心脏谱系的分化潜能。方法实验分为:不同培养时间CDMCs (第3、5、7代),并以脐带间充质干细胞 (UCMSCs)为对照。分析各细胞分子表型并向心脏谱系诱导分化。显微镜观察细胞形态;计算生长倍增时间并绘制细胞生长曲线;流式细胞术分析表面标志抗原表达;实时定量PCR和Western blot分别测干细胞多能分子及组织特异性分子mRNA和蛋白表达。结果采用重复测量资料方差分析、单因素方差分析和配对t检验。结果 CDMCs具有UCMSCs形态特征与增殖能力,体外培养1 ~ 7 d,与UCMSCs比较,P3、5、7代CDMCs增殖能力差异无统计学意义 (P> 0.05)。与UCMSCs相比,不同培养时间CDMCs表面标志抗原 (CD90)表达 (冻存前:97.13%±2.00%比59.87%±34.14%、38.83%±11.04%、34.77±14.78%;冻存后:99.83%±0.17%比56.00%±19.47%、47.48±11.88%、41.15±8.68%)降低(P< 0.05)。与UCMSCs相比,不同培养时间CDMCs中Rex1 (0.00±0.00比0.68±0.50、0.29±0.17、0.38±0.50)、Oct3/4 (1.00±0.02比5.28±0.78、3.88±0.95、3.63±0.34)、Nanog(1.00±0.16比7.57±4.69、5.40±3.58、5.34±0.76)以及心脏特异转录因子Nkx2.5 (1.00±0.12比30.60±22.43、19.69±9.65、8.82±4.94)、Gata4 (1.00±0.85比60467±25266、44350±25800、35067±23113)表达均增高,差异有统计学意义 (P均< 0.05)。与诱导前比较,向心肌诱导分化15 d后,不同培养时间CDMCs中cTnT蛋白表达水平 (0.40±0.13比0.98±0.16、0.38±0.18 比0.69±0.15、0.17±0.11比0.70±0.17)增高 (P< 0.05)。结论 CDMCs不仅具备部分干细胞和间充质细胞表型,还具有心脏组织特异性。其具备心脏谱系分化潜能,心肌细胞分化能力可能优于UCMSCs。