Nouvelle Synthèse de l’α-Damascone

The gardenia absolute was separated into basic, phenolic, acidic, lactonic and neutral fractions and analysed by using GC, combined GC-MS, IR and NMR. A total of 130 components was identified. Among them, the characteristic constituents responsible for the sweet-green odor of this flower were jasmin lactone, cis-3-hexenol, esters of cis-3-hexenol, cis-3-hexenoic acid and tiglic acid.     

斑马鱼心脏发育标记基因Wnt11的多克隆抗体制备

Wnt11为Wnt家族的成员,是参与Wnt信号途径调控的转录因子,对心脏的正常发育起着非常重要的作用.根据已报道的Wnt11基因序列,通过RT-PCR从斑马鱼心脏组织中得到Wnt11部分编码区序列,将其连接到pGEX-4T-1原核表达载体上.经酶切及测序鉴定后,质粒构建成功,将重组质粒(pGEX-4T-Wnt11)转化E.coli BL2l,通过IPTG诱导表达出融合蛋白,采用谷胱甘肽琼脂糖珠亲和纯化.将纯化的融合蛋白免疫新西兰大白兔制备多克隆抗体,并用Western Blot检测抗体的效价和特异性.结果显示,获得了Wnt11原核表达重组融合蛋白及高效价的特异性兔抗Wnt11多克隆抗体,为Wnt11功能的进一步研究奠定了基础.     

Rab11的结构特征、效应因子与功能

Rab11是Rab小分子GTP酶家族的成员.在细胞内膜泡再循环途径中,Rab11作为重要调节因子,介导膜泡从内体向质膜的运输.近年来随着对Rab11研究的深入,人们发现该蛋白质在多种细胞生命活动中发挥着关键作用.现对Rab11的结构、效应蛋白及功能等方面进行了综述.     

甲醇利用菌SDM11中glyA基因的克隆及其在大肠杆菌中的表达

对甲醇降解菌Methylobacterium.sp SDM11中的glyA基因进行克隆及特性研究,以获得更多的丝氨酸羟甲基转移酶(serine hydroxymethyltransferase,SHMT)资源。根据GenBank中已报道的Methylobacterium extorquensAM1中的glyA基因序列(登录号:L33463)设计引物,以SDM11的基因组DNA为模板,PCR扩增glyA基因。利用pETblue-2载体将该基因在大肠杆菌BL21(DE3)中得到表达。PCR扩增到一个1.40 kb大小的DNA片段,经过blast软件比对分析,发现该片段与已报道的Methylobacterium extorquensAM1的glyA基因的序列相似性为95%,氨基酸序列的相似性为98%。该基因编码468个氨基酸,预测的分子量大小为52.2 kD,等电点为7.02,发现纯化后的目标蛋白具有SHMT酶活性,并初步测定了酶活力。     

水稻Qb-SNARE蛋白OsNPSN11多克隆抗体制备、鉴定与应用

在真核生物细胞囊泡运输过程中的膜融合主要是由SNARE蛋白介导的, OsNPSN11是从水稻中克隆的Qb-SNARE家族基因, 文章将OsNPSN11构建到原核表达载体pET-30a中与6个His标签融合, 重组质粒pET-OsNPSN11转化BL21(DE3)0.5 mmol/L IPTG诱导4 h后获得了高效表达。用镍离子亲和树脂(Ni²⁺-NTA His Bind Resin) 纯化融合蛋白, 以纯化后的蛋白为抗原免疫新西兰家兔制备多克隆抗体, Western blotting结果显示, 该抗体能特异识别在原核系统表达的抗原, 以及水稻不同组织质膜组分中的OsNPSN11, 可用于转基因水稻中目标蛋白的表达分析。     

耐唑类药白念珠菌ERG11基因点突变

ERG11是唑类抗真菌药对白念珠菌作用靶酶羊毛甾醇14α-去甲基化酶（14DM）的编码基因,ERG11基因的有义突变会使靶酶发生氨基酸置换,影响酶与药物分子的结合,是导致菌株耐药的原因之一。14DM具有特定的空间构型,突变所处的位置决定能否导致菌株耐药,已发现的60余种ERG11点突变里面,仅有数种被实验证实可致耐药。     

Rab11-FIP4 interacts with Rab11 in a GTP-dependent manner and its overexpression condenses the Rab11 positive compartment in HeLa cells

We have recently identified Rab11-FIP4 as the sixth member of the Rab11-FIP family of Rab11 interacting proteins. Here, we demonstrate that Rab11-FIP4 interacts with Rab11 in a GTP-dependent manner and that its C-terminal region allows the protein to self-interact and interact with pp75/Rip11, Rab11-FIP2, and Rab11-FIP3. However, Rab11-FIP4 does not appear to interact directly with Rab coupling protein (RCP). We investigated the subcellular localisation of Rab11-FIP4 in HeLa cells and show that it colocalises extensively with transferrin and with Rab11. Furthermore, when overexpressed, it causes a condensation of the Rab11 compartment in the perinuclear region. We demonstrate that the carboxy-terminal region of Rab11-FIP4 (Rab11-FIP4(C-ter)) is necessary and sufficient for its endosomal membrane association. Expression of Rab11-FIP4(C-ter) causes a dispersal of the Rab11 compartment towards the cell periphery and does not inhibit transferrin recycling in HeLa cells. It is likely that Rab11-FIP4 serves as a Rab11 effector in a Rab11 mediated function other than transferrin recycling.     

A subtle interplay between three Pex11 proteins shapes de novo formation and fission of peroxisomes

The organization of eukaryotic cells into membrane-bound compartments must be faithfully sustained for survival of the cell. A subtle equilibrium exists between the degradation and the proliferation of organelles. Commonly, proliferation is initiated by a membrane remodeling process. Here, we dissect the function of proteins driving organelle proliferation in the particular case of peroxisomes. These organelles are formed either through a growth and division process from existing peroxisomes or de novo from the endoplasmic reticulum (ER). Among the proteins involved in the biogenesis of peroxisomes, peroxins, members of the Pex11 protein family participate in peroxisomal membrane alterations. In the yeast Saccharomyces cerevisiae, the Pex11 family consists of three proteins, Pex11p, Pex25p and Pex27p. Here we demonstrate that yeast mutants lacking peroxisomes require the presence of Pex25p to regenerate this organelle de novo. We also provide evidence showing that Pex27p inhibits peroxisomal function and illustrate that Pex25p initiates elongation of the peroxisomal membrane. Our data establish that although structurally conserved each of the three Pex11 protein family members plays a distinct role. While ScPex11p promotes the proliferation of peroxisomes already present in the cell, ScPex25p initiates remodeling at the peroxisomal membrane and ScPex27p acts to counter this activity. In addition, we reveal that ScPex25p acts in concert with Pex3p in the initiation of de novo peroxisome biogenesis from the ER.     

Expression of a bioactive recombinant human interleukin-11 in chicken HD11 cell line

To direct the synthesis and secretion of recombinant human interleukin-11 (rhIL-11) in chicken HD11 cells, a plasmid targeting the c-lysozyme gene has been constructed which contains the mature cytokine cDNA in frame with the lysozyme leader sequence. The upregulation of rhIL-11 mediated by LPS proves the knock-in of hIL-11 cDNA in the lysozyme gene. The bioactivity of the expressed protein is demonstrated and quantified with the hIL-11 dependent 7TD1 and B9 cell lines. The electrophoretic mobility, receptor binding properties and growth promoting effect of the chicken-derived cytokine are identical to those of a rhIL-11 expressed in Escherichia coli. These results describe the secretion of a biologically active rhIL-11 expressed by an avian cellular machinery.     

Hydrolytic behavior of 5alpha-hydroxy-11beta- and 5beta-hydroxy-11alpha-substituted 19-norsteroids

Teutsch G. and Bélanger A. treated 5alpha,10alpha epoxides with Grignard-reagents catalyzed by copper(I) ions. The reaction with steroidal epoxides proceeded with complete regio- and stereospecificity, leading exclusively to the 11beta-substituted compounds. According to our synthetic strategy, the 5,10 epoxide isomers were not separated; instead, the pure 11beta, and in some cases, 11alpha-substituted molecules were isolated after the conjugate addition of the Grignard-reagents, followed by deketalization and dehydration. Surprisingly, appearance of a third compound was generally observed beside the expected deprotected products, and this compound turned out to have a 3-keto-5(10),9(11) structural unit. Starting from pure 3-ethylenedioxy-5alpha,10alpha-epoxy-estr-9(11)-ene-17-one and 3-ethylenedioxy-5beta,10beta-epoxy-estr-9(11)-ene-17-one, four model compounds were synthesized (11alpha- and 11beta-[4-[1,1-(ethylenedioxy)-ethyl]phenyl]-estra-, as well as 11alpha- and 11beta-cyclohexyl-estra-derivatives) to study the process of deprotection and dehydration. 3-keto-5(10),9(11)-derivatives were found to form after deketalization and dehydration only from 11alpha-substituted derivatives, while 11beta-derivatives resulted in only the expected 3-keto-5,9-diene structure. After observing this remarkable difference between the behavior of 11alpha-, 11beta-substituted isomers we decided to take a closer look at the processes of deketalization and dehydration. In order to carry out the hydrolysis under mild conditions, pyridinium paratoluenesulfonate, a weakly acidic salt, was applied. All the intermediate products observed by TLC were isolated. The outcome of the deprotection and elimination reactions can be rationalized by two factors: conjugation of olefins (with the 3-oxo-group or the 11-phenyl group) and orientation of groups to be eliminated.     

Experiencia de una Unidad de Prevención de Caídas de un hospital de cuidados intermedios

Introduction

The aim of this study is to determine clinical features and interventions in patients attended in our hospital falls prevention unit.

Material and methods

Medical records and evaluation protocols from October 2010 to June 2012 were reviewed. Results are expressed in means and standard deviation.

Results

We studied 68 patients: 53 came due to falls (77.9%), and 15 (22%) due to gait disorders. The mean age was 77.6±7.9. Number of women: 63 (92.6%). Previous Barthel Index was 94/100, cognitive impairment 23 (33.8%), polypharmacy 69.1%, orthostatic hypotension 18 (26.4%). Walking speed 0.66± 0.19 m/s and Time up and go to (TUG) 16.6±4.5 s. Post-urography detected vestibular dysfunction in 34 patients (77%). Clinical cause of fall and/or gait disorder was multifactorial in 33 (48.5%), Parkinsonism 19 (27.9%), chronic pain/arthropathy 8 (11.4%), and vestibular syndrome 8 (11.4%). Two-thirds (45; 66.1%) of the patients began Physical therapy, and vitamin D was given to 47 (69.1%). Phone calls were made to patients and/or their relatives and noted that after 3 months of the treatment: 48 (70.5%) had no fall; 59 (86.7%) patients followed the recommendations, and 57 (83.8%) were satisfied.

Conclusions

In this sample of older patients, mostly female with a good functional and cognitive condition, the causes of the falls were multifactorial in the half of the cases, and the post-urography detected vestibular changes in the half of the patients.     

Action de l'hydrate de chloral sur les mitoses de segmentation de l'œuf de pleurodèle

In eggs of Pleurodeles treated with chloralhydrate (0.1 M) spindle and astral fibers are progressively destroyed after 4 hours, leading to apolar nuclei, apolar mitoses and “monopolar” mitoses, the so-called star metaphases. After 1 hour the spindle is shortened, but not narrowed and separated from the poles and asters. Its microtubules, grown before metaphase, are first inhibited at their ends near the centrospheres. After 4 hours, defibrillated achromatic material, stained by methyl blue, surrounds a clearer zone originating from the nucleoplasm, in which chromosomes are embedded. At the EM level the treatment induces the formation of unusual tubular bodies connected with the centrospheres and of similar bodies related to kinetochores and chromosomes. These bodies are formed of tubular residues, parallel or in concentric systems, the latter embedded in a matrix containing tightly packed filaments of 170 Å diameter. The star metaphase is characterized by homogeneous centrospheres formed only of filaments and completely independent from kinetochores and chromosomes. Chromosomes are radially distributed around a central common mass, which keeps the chromosomes together; it is formed of a finely fibrous matrix containing disordered microtubular residues; kinetochores are embedded in the common mass. Fuzziness and alteration of chromosomes proceed as a direct action of the chloralhydrate. The star metaphase is not a real “monopolar” mitosis.     

Over de verdeeling van de agglutininen over de serumeiwitten

Ohne Zusammenfassung Voordracht voor de Vergadering van de Ned. Ver. v. Microbiologie, gehouden te Utrecht op 12 November 1938. Uitvoerige publicatie met literatuur volgt in den vorm van een dissertatie.