pORE: a modular binary vector series suited for both monocot and dicot plant transformation

We present a series of 14 binary vectors suitable for Agrobacterium-mediated transformation of dicotyledonous plants and adaptable for biolistic transformation of monocotyledonous plants. The vector size has been minimized by eliminating all non-essential elements from the vector backbone and T-DNA regions while maintaining the ability to replicate independently. The smallest of the vector series is 6.3 kb and possesses an extensive multiple cloning site with 21 unique restriction endonuclease sites that are compatible with common cloning, protein expression, yeast two-hybrid and other binary vectors. The T-DNA region was engineered using a synthetic designer oligonucleotide resulting in an entirely modular system whereby any vector element can be independently exchanged. The high copy number ColE1 origin of replication has been included to enhance plasmid yield in Escherichia coli. FRT recombination sites flank the selectable marker cassette regions and allow for in planta excision by FLP recombinase. The pORE series consists of three basic types; an ‘open’ set for general plant transformation, a ‘reporter’ set for promoter analysis and an ‘expression’ set for constitutive expression of transgenes. The sets comprise various combinations of promoters (P _HPL, P _ENTCUP2 and P _TAPADH), selectable markers (nptII and pat) and reporter genes (gusA and smgfp).     

The design, synthesis, and biological evaluation of novel substituted purines as HIV-1 Tat-TAR inhibitors

A series of novel substituted purines containing a side chain with a terminal amino or guanidyl group were designed and synthesized as HIV-1 Tat-TAR inhibitors. All the compounds could effectively block the TAR transactivation in human 293T cells with the CAT expression percentage ranging from 34.4% to 65.7% and showed high antiviral effects with low cytotoxicities in inhibiting the formation of SIV-induced syncytium in CEM174 cells. Molecular modeling studies by Auto-dock process suggest that the compounds bind to TAR RNA in two different modes.     

Comparison of pesticide sensitivity by electrochemical test based on acetylcholinesterase biosensor

Based on the change in electrochemical behavior of enzymatic activity induced by pesticide, a novel electrochemical method has been devised for investigation of pesticide sensitivity using acetylcholinesterase (AChE) biosensor. Because of the excellent biocompatibility and good stability of chitosan matrix, it prevented leakage of the AChE from electrode. Multiwall carbon nanotube (MWNT) promoted electron transfer reaction at a lower potential and catalyzed the electro-oxidation of thiocholine, thus amplifying the sensitivity and amperometric response of the biosensor. Four pesticides of carbaryl, malathion, dimethoate and monocrotophos were selected to discuss their inhibition efficiencies to AChE. The inhibition curves were similar to Michealis-Menten and the Michealis-Menten constants (Km) were calculated to be 0.96 microM, 1.78 microM, 1.97 microM and 4.28 microM, respectively. Ninety-five percent reactivation of the inhibited AChE could be regenerated using pralidoxime iodide within 8 min. The proposed electrochemical pesticide sensitivity test exhibited high sensitivity, low cost and simplified procedures, which is a promising new tool for comparison of pesticide sensitivity and for selection of the most efficient enzyme inhibitors.     

药源植物盾叶薯蓣甾体皂苷及皂苷元的研究进展

盾叶薯蓣是重要的甾体激素类药源植物,其根茎中薯蓣皂苷元含量居薯蓣属植物之冠,为我国的特有种。为了寻找高含量的资源、筛选新的生理活性成分,多年来我国学者做了大量的研究工作。主要概括了盾叶薯蓣的资源分布、薯蓣皂苷元的提取工艺、化学成分、药理、含量测定等方面的研究。     

G蛋白偶联受体突变及其相关疾病

G蛋白偶联受体（GPCR）是最大的蛋白质受体超家族之一,参与调节各种生理过程,在信号识别和转导中起重要作用。GPCR的突变及基因多态性将引发各种疾病,目前已经发现有30多种单基因疾病与此相关。介绍了GPCR功能失调的分子基础,在此基础上对一些GPCR突变以及相关疾病做了综逑,并指出了其治疗意义。     

Preparation and biomedical application of a non-polymer coated superparamagnetic nanoparticle

We report the preparation of a non-polymer coated superparamagnetic nanoparticle that is stable and biocompatible both in vitro and in vivo. The non-polymer, betaine, is a natural methylating agent in mammalian liver with active surface property. Upon systemic administration, the nanoparticle has preferential biodistribution in mammalian liver and exhibits good reduction of relaxivity time and negative enhancement for the detection of hepatoma nodules in rats using MRI. Our data demonstrate that the non-polymer coated superparamagnetic nanoparticle should have potential applications in biomedicine.     

Restoration of cone vision in a mouse model of achromatopsia

Loss of cone function in the central retina is a pivotal event in the development of severe vision impairment for many prevalent blinding diseases. Complete achromatopsia is a genetic defect resulting in cone vision loss in 1 in 30,000 individuals. Using adeno-associated virus (AAV) gene therapy, we show that it is possible to target cones and rescue both the cone-mediated electroretinogram response and visual acuity in the Gnat2 ( cpfl3 ) mouse model of achromatopsia.     

Stem cells act through multiple mechanisms to benefit mice with neurodegenerative metabolic disease

Intracranial transplantation of neural stem cells (NSCs) delayed disease onset, preserved motor function, reduced pathology and prolonged survival in a mouse model of Sandhoff disease, a lethal gangliosidosis. Although donor-derived neurons were electrophysiologically active within chimeric regions, the small degree of neuronal replacement alone could not account for the improvement. NSCs also increased brain beta-hexosaminidase levels, reduced ganglioside storage and diminished activated microgliosis. Additionally, when oral glycosphingolipid biosynthesis inhibitors (beta-hexosaminidase substrate inhibitors) were combined with NSC transplantation, substantial synergy resulted. Efficacy extended to human NSCs, both to those isolated directly from the central nervous system (CNS) and to those derived secondarily from embryonic stem cells. Appreciating that NSCs exhibit a broad repertoire of potentially therapeutic actions, of which neuronal replacement is but one, may help in formulating rational multimodal strategies for the treatment of neurodegenerative diseases.     

Dominance of the alpha1B-adrenergic receptor and its subcellular localization in human and TRAMP prostate cancer cell lines

The function and distribution of alpha1-adrenergic receptor (AR) subtypes in prostate cancer cells is well characterized. Previous studies have used RNA localization or low-avidity antibodies in tissue or cell lines to determine the alpha1-AR subtype and suggested that the alpha1A-AR is dominant. Two androgen-insensitive, human metastatic cancer cell lines DU145 and PC3 were used as well as the mouse TRAMP C1-C3 primary and clonal cell lines. The density of alpha1-ARs was determined by saturation binding and the distribution of the different alpha1-AR subtypes was examined by competition-binding experiments. In contrast to previous studies, the major alpha1-AR subtype in DU145, PC3 and all of the TRAMP cell lines is the alpha1B-AR. DU145 cells contained 100% of the alpha1B-AR subtype, whereas PC3 cells were composed of 21% alpha1 A-AR and 79% alpha1B-AR. TRAMP cell lines contained between 66% and 79% of the alpha1B-AR with minor fractions of the other two subtypes. Faster doubling time in the TRAMP cell lines correlated with decreasing alpha 1B-AR and increasing alpha1 A- and alpha1D-AR densities. Transfection with EGFP-tagged alpha1B-ARs revealed that localization was mainly intracellular, but the majority of the receptors translocated to the cell surface after extended preincubation (18 hr) with either agonist or antagonist. Localization was confirmed by ligand-binding studies and inositol phosphate assays where prolonged preincubation with either agonist and/or antagonist increased the density and function of alpha 1-ARs, suggesting that the native receptors were mostly intracellular and nonfunctional. Our studies indicate that alpha1B-ARs are the major alpha1-AR subtype expressed in DU145, PC3, and all TRAMP cell lines, but most of the receptor is localized in intracellular compartments in a nonfunctional state, which can be rescued upon prolonged incubation with any ligand.