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991.
Mai Kanke Kohei Nishimura Masato Kanemaki Tatsuo Kakimoto Tatsuro S Takahashi Takuro Nakagawa Hisao Masukata 《BMC cell biology》2011,12(1):8
Background
Inducible inactivation of a protein is a powerful approach for analysis of its function within cells. Fission yeast is a useful model for studying the fundamental mechanisms such as chromosome maintenance and cell cycle. However, previously published strategies for protein-depletion are successful only for some proteins in some specific conditions and still do not achieve efficient depletion to cause acute phenotypes such as immediate cell cycle arrest. The aim of this work was to construct a useful and powerful protein-depletion system in Shizosaccaromyces pombe. 相似文献992.
Liu T Yu H Zhang C Lu M Piao Y Ohba M Tang M Yuan X Wei S Wang K Ma A Feng X Qin S Mukai C Tsuji A Jin F 《Applied and environmental microbiology》2012,78(13):4752-4754
A novel rutin-α-L-rhamnosidase hydrolyzing α-L-rhamnoside of rutin, naringin, and hesperidin was purified and characterized from Aspergillus niger DLFCC-90, and the gene encoding this enzyme, which is highly homologous to the α-amylase gene, was cloned and expressed in Pichia pastoris GS115. The novel enzyme was classified in glycoside-hydrolase (GH) family 13. 相似文献
993.
994.
995.
Background
Community-based organizations (CBOs) are important stakeholders in health systems and are increasingly called upon to use research evidence to inform their advocacy, program planning, and service delivery efforts. CBOs increasingly turn to community-based research (CBR) given its participatory focus and emphasis on linking research to action. In order to further facilitate the use of research evidence by CBOs, we have developed a strategy for community-based knowledge transfer and exchange (KTE) that helps CBOs more effectively link research evidence to action. We developed the strategy by: outlining the primary characteristics of CBOs and why they are important stakeholders in health systems; describing the concepts and methods for CBR and for KTE; comparing the efforts of CBR to link research evidence to action to those discussed in the KTE literature; and using the comparison to develop a framework for community-based KTE that builds on both the strengths of CBR and existing KTE frameworks.Discussion
We find that CBR is particularly effective at fostering a climate for using research evidence and producing research evidence relevant to CBOs through community participation. However, CBOs are not always as engaged in activities to link research evidence to action on a larger scale or to evaluate these efforts. Therefore, our strategy for community-based KTE focuses on: an expanded model of 'linkage and exchange' (i.e., producers and users of researchers engaging in a process of asking and answering questions together); a greater emphasis on both producing and disseminating systematic reviews that address topics of interest to CBOs; developing a large-scale evidence service consisting of both 'push' efforts and efforts to facilitate 'pull' that highlight actionable messages from community relevant systematic reviews in a user-friendly way; and rigorous evaluations of efforts for linking research evidence to action.Summary
Through this type of strategy, use of research evidence for CBO advocacy, program planning, and service delivery efforts can be better facilitated and continually refined through ongoing evaluations of its impact.996.
Chien-Li Chiu Jen-Leih Wu Guor-Mour Her Yi-Li Chou Jiann-Ruey Hong 《Apoptosis : an international journal on programmed cell death》2010,15(6):653-668
Aquatic birnavirus induces post-apoptotic necrotic cell death via a newly synthesized protein-dependent pathway. However,
the involvement of viral genome-encoded protein(s) in this death process remains unknown. In the present study, we demonstrated
that the submajor capsid protein, VP3, up-regulates the pro-apoptotic protein, Bad, in fish and mouse cells. Western blot
analysis revealed that VP3 was expressed in CHSE-214 cells at 4 h post-infection (pi), indicating an early role during viral replication. We cloned
the VP3 gene and tested its function in fish and mouse cells; VP3 overexpression induced apoptotic cell death by TUNEL assay. In
addition, it up-regulated Bad gene expression in zebrafish ZLE cells by threefold at 12 h post-transfection (pt) and in mouse NIH3T3 cells by tenfold at
24 h pt. VP3 up-regulation of Bad expression altered mitochondria function, inducing mitochondrial membrane potential (MMP)
loss and activating initiator caspase-9 and effector caspase-3. Furthermore, reduced Bad expression (65% reduction), MMP loss
(up to 40%), and enhanced cell viability (up to 60%) upon expression of VP3 antisense RNA in CHSE-214 cells at 24 h post-IPNV
infection was observed. Finally, overexpression of the anti-apoptotic gene, zfBcl-xL, reduced VP3-induced apoptotic cell death and caspase-3 activation at 24 h in fish cells. Taken together, these results suggest
that aquatic birnavirus VP3 induces apoptosis via up-regulation of Bad expression and mitochondrial disruption, which activates a downstream caspase-3-mediated death pathway that is blocked by
zfBcl-xL. 相似文献
997.
Laima Česonienė Remigijus Daubaras Jonė Venclovienė Pranas Viškelis 《Central European Journal of Biology》2010,5(6):864-871
Interest in the biochemical composition of Viburnum opulus fruit has intensified due to the food industry’s demand for natural vitamins, pigments and other substances that enhance the value of different foods. The present study was conducted to determine the agro-biological and biochemical variability of V. opulus and to select the genotypes that could best serve as sources of health promoting substances. Twelve selected genotypes were evaluated. ‘Leningradskaya Otbornaya’, V. opulus var. americanum, ‘Zarnitsa’, and local clone P2 were determined to be the best genotypes for growth in commercial plantations. Fruits of the local clone P3 were characterised by large amounts of total phenolics, ascorbic acid, and reducing sugars. V. opulus var. sargentii and V. opulus var. americanum contained exceptionally large amounts of total phenolics, 1460.0 and 1400.0 mg/100 g, respectively. The amount of ascorbic acid varied from 12.4 to 41.4 mg/100 g, the amount of carotenoids varied from 1.4 to 2.8 mg/100 g, the amount of anthocyanins varied from 23.2 to 44.6 mg/100 g, and the amount of total phenolics varied from 753.0 to 1460.0 mg/100 g. The presence of these large amounts of biologically active compounds enables their use as potent antioxidants. The data describing agro-biological characteristics, biochemical components, and health promoting activities of V. opulus fruits will increase the understanding of this plant and facilitate its use in the food and pharmaceuticals industry. 相似文献
998.
Beob G. Kim Julye M. Adams Brian A. Jackson Merlin D. Lindemann 《Biological trace element research》2010,133(2):171-180
Dietary chromium(III) picolinate (CrPic) effects on circulating steroid hormones have been reported in various experimental
animals. However, direct effects of CrPic on adrenocortical steroidogenesis are uncertain. Therefore, the objective was to
determine the effects of CrPic on cortisol and dehydroepiandrosterone sulfate (DHEAs) secretion from H295R cells. In experiment
1, a 24-h exposure to CrPic (0 to 200 μM) had both linear (p < 0.001) and quadratic (p < 0.001) effects on cortisol secretion from forskolin-stimulated cells with the highest cortisol secretion at 0.1 μM of CrPic
and the lowest at 200 μM of CrPic. In experiment 2, a 48-h exposure to CrPic (200 μM) decreased cortisol (p < 0.07) release from forskolin-stimulated cells during a 24-h collection period. In experiment 3, a 48-h exposure to CrPic
(100 μM) decreased cortisol (p < 0.05) and DHEAs (p < 0.01) from forskolin-stimulated cells during a 24-h sampling period. In experiment 4, a 24-h exposure to forskolin followed
by a 24-h exposure to both forskolin and CrPic (100 and 200 μM) decreased both cortisol and DHEAs secretion (p < 0.01). This study suggests that at high concentrations, CrPic inhibits aspects of steroidogenesis in agonist-stimulated
adrenocortical cells. 相似文献
999.
Arenahalli Ningegowda Madhu Prashant Giribhattanavar Mandayam Singara Narayan Siddalingaiya Gurudutt Prapulla 《Biotechnology letters》2010,32(4):503-506
Vitamin B12 was produced by probiotic Lactobacillus plantarum in submerged fermentation (96 h) with successive anaerobic and aerobic phases of 48 h each to give 13 ng vitamin B12/g dry biomass. Sodium cyanide-mediated cell lysis, followed by benzyl alcohol/chloroform/water extraction, improved the release of intracellular vitamin B12 for analysis. The presence of the K+ adduct of cyanocobalamin (m/z of 1394) was established using electron spray ionization–mass spectra; growth of a mutant of Escherichia coli in the presence of cyanocobalamin ascertained its bioavailability. 相似文献
1000.
Plasmacytoid dendritic cells (pDCs) represent a unique and crucial immune cell population capable of producing large amounts
of type I interferons (IFNs) in response to viral infection. The function of pDCs as the professional type I IFN-producing
cells is linked to their selective expression of Toll-like receptor 7 (TLR7) and TLR9, which sense viral nucleic acids within
the endosomal compartments. Type I IFNs produced by pDCs not only directly inhibit viral replication but also play an essential
role in linking the innate and adaptive immune system. The aberrant activation of pDCs by self nucleic acids through TLR signaling
and the ongoing production of type I IFNs do occur in some autoimmune diseases. Therefore, pDC may serve as an attractive
target for therapeutic manipulations of the immune system to treat viral infectious diseases and autoimmune diseases. 相似文献