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111.
Capsule The occurrence of the Middle Spotted Woodpecker in northern Switzerland was related to the availability of large oaks and standing dead trees, but not to trees with fruiting Common Ivy. 相似文献
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113.
The insect baculovirus AcMNPV (Autographa californica multiple nuclear polyhedrosis virus) enters many mammalian cell lines, prompting its application as a general eukaryotic gene delivery agent, but the basis of entry is poorly understood. For adherent mammalian cells, we show that entry is favoured by low pH and by increasing the available cell-surface area through a transient release from the substratum. Low pH also stimulated baculovirus entry into mammalian cells grown in suspension which, optimally, could reach 90% of the transduced population. The basic loop, residues 268–281, of the viral surface glycoprotein gp64 was required for entry and a tetra mutant with increasing basicity increased entry into a range of mammalian cells. The same mutant failed to plaque in Sf9 cells, instead showing individual cell entry and minimal cell-to-cell spread, consistent with an altered fusion phenotype. Viruses grown in different insect cells showed different mammalian cell entry efficiencies, suggesting that additional factors also govern entry. 相似文献
114.
L. M. Skivka O. G. Fedorchuk M. P. Rudyk V. V. Pozur N. M. Khranovska M. Yu. Grom J. W. Nowicky 《Cytology and Genetics》2013,47(5):318-328
Hypoxia is an important factor in the macrophages microenvironment. Many physiological and pathological processes including solid tumor development are characterized by both low oxygen content and presence of macrophages. Tumor-associated hypoxia causes alternative polarization of macrophages in tumor tissue and transformation of these cells into the allies of a malignant neoplasm. The aim of the work was to investigate the effect of NSC631570, a cancer-selective drug that is known to selectively accumulate in the tumor tissue, on hypoxic macrophage function. Murine peritoneal macrophages (PMs) were subjected to hypoxia (3% O2). Nitrite level was assayed by the Griess reaction. Arginase activity was measured by colorimetric method. ROS generation and phagocytosis was estimated by flow cytometry. O 2 ? generation was assayed by the NBT reduction method. HMGB1 expression was determined by ELISA. 42 h hypoxia caused alternative polarization of murine PMs with significant arginase prevalence. NSC631570 repolarized arginine metabolism of hypoxic macrophages to NOS dominant and activated their pro-inflammatory functions: recovered ROS production and increased alarmin release. Thus, NSC631570 can restore pro-inflammatory functions of macrophages, alternatively polarized by hypoxia. 相似文献
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116.
Sergio Rosales-Mendoza Luz María Teresita Paz-Maldonado Dania O. Govea-Alonso Schuyler S. Korban 《Plant Cell, Tissue and Organ Culture》2013,112(2):159-169
To date, a number of antihypertensive peptides (AHPs) have been identified. Most of these are derived from proteins present in common edible consumables, including milk, egg, and plant foods. Consumption of these foods serves as means of AHP delivery and thus contributing favorable health benefits. It is hypothesized that food crops, either over-expressing AHP precursor proteins or producing particular peptides as heterologous components, may serve as viable vehicles for production and delivery of functional foods as alternative hypertension therapies. In recent years, genetic engineering efforts have been undertaken to add value to functional foods. Pioneering approaches have been pursued in several crop plants, such as rice and soybean. In this review, a summary of current tools used for discovery of new AHPs, as well as strategies and perspectives of capitalizing on these AHPs in genetic engineering efforts will be presented and discussed. The implications of these efforts on the development of functional foods for preventing and treating hypertension are also presented. 相似文献
117.
L. Cantelmo B. O. Soares L. P. Rocha J. A. Pettinelli C. H. Callado E. Mansur A. Castellar R. F. Gagliardi 《Plant Cell, Tissue and Organ Culture》2013,115(3):385-393
Leaf segments from in vitro-grown shoot cultures of Petiveria alliacea were incubated on Murashige and Skoog (MS) medium supplemented with different concentrations of zeatin, thidiazuron, 2,4-dichlorophenoxyacetic acid (2,4-D) or picloram (PIC). Direct somatic embryogenesis was induced in response to all tested concentrations of 2,4-D and PIC. Primary somatic embryos displayed highly repetitive embryogenesis, both on the induction medium and in liquid hormone-free MS medium. Plantlets were obtained from these secondary embryos at an estimated frequency of 5 %, after 180 days of culture on half-strength MS medium gelled with 0.2 % Phytagel. Simultaneous development of friable non-embryogenic callus was also observed on media containing PIC or 2,4-D at different concentrations. Cell suspension cultures initiated from these callus tissues did not show an increase in biomass. The embryogenic portions formed at the surface of the explants in response to 20.0 μM PIC were inoculated in hormone-free full-or half-strength liquid MS medium (MS0) and showed high rates of secondary embryogenesis, resulting in the production of a mean of 35 embryos for each embryo inoculated at the culture initiation. Embryos that started the conversion process in the liquid MS0 medium originated whole plants at a frequency of 100 % when transferred to MS0 medium solidified with 0.7 % agar. Acclimatization was achieved in 90 % of the converted plantlets, with the production of phenotypically normal plants. This system is potentially useful for the micropropagation of this species, as well as for the production of substances with pharmacological interest, such as dibenzyl trisulfide. 相似文献
118.
119.
Steven R. LaPlante François Bilodeau Norman Aubry James R. Gillard Jeff O’Meara René Coulombe 《Bioorganic & medicinal chemistry letters》2013,23(16):4663-4668
A classic synthetic issue that remains unresolved is the reaction that involves the control of N- versus O-alkylation of ambident anions. This common chemical transformation is important for medicinal chemists, who require predictable and reliable protocols for the rapid synthesis of inhibitors. The uncertainty of whether the product(s) are N- and/or O-alkylated is common and can be costly if undetermined. Herein, we report an NMR-based strategy that focuses on distinguishing inhibitors and intermediates that are N- or O-alkylated. The NMR strategy involves three independent and complementary methods. However, any combination of two of the methods can be reliable if the third were compromised due to resonance overlap or other issues. The timely nature of these methods (HSQC/HMQC, HMBC. ROESY, and 13C shift predictions) allows for contemporaneous determination of regioselective alkylation as needed during the optimization of synthetic routes. 相似文献
120.
Richard K. Amewu James Chadwick Afthab Hussain Somnath Panda Rinki Rinki Omar Janneh Stephen A. Ward Candel Miguel Hollie Burrell-Saward Livia Vivas Paul M. O’Neill 《Bioorganic & medicinal chemistry》2013,21(23):7392-7397
The synthesis of a range of mono spiro and dispiro 1,2,4,5-tetraoxane dimers is described. Selected molecules were examined in in vitro assays to determine their antimalarial and anticancer potential. Our studies reveal that several molecules possess potent nanomolar antimalarial and single digit micromolar antiproliferative IC50s versus colon (HT29-AK and leukemia (HL60) cell lines. 相似文献