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981.
Katsunori Motosaka Masayuki Koganezawa Satoko Narikawa Akira Furuyama Kenji Shinozaki Kunio Isono Ichiro Shimada 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2007,193(2):279-283
Acute choice behavior in ingesting two different concentrations of sucrose in Drosophila is presumed to include learning and memory. Effects on this behavior were examined for four mutations that block associative
learning (dunce, rutabaga, amnesiac, and radish). Three of these mutations cause cyclic AMP signaling defects and significantly reduced taste discrimination. The exception
was radish, which affects neither. Electrophysiological recordings confirmed that the sensitivity of taste receptors is almost indistinguishable
in all flies, whether wild type or mutant. These results suggest that food choice behavior in Drosophila involves central nervous learning and memory operating via cyclic AMP signaling pathways. 相似文献
982.
Mariëtte van Amstel Claar de Brauw Peter Driessen Pieter Glasbergen 《Biodiversity and Conservation》2007,16(14):4109-4129
This paper seeks to understand why multinationals prefer to launch a label specific to their own product and examines how
reliable these product-specific eco-labels are. A new methodology is applied to assess the extent to which eco-labels live
up to claims about their contribution to conservation and the sustainable use of agricultural biodiversity. Product-specific
eco-labels are considered as industry self-regulation and all three regulatory stages are studied: the planning, implementation
and outcome stage. There are major differences between the product specific eco-labels in the degree in which agrobiodiversity
management is part of the normative labeling schemes. Although there are some problems of reliability, such as transparency
in the implementation stage and the monitoring in the outcome stage, the degree of reliability of product-specific labels
is comparable with eco-labels of international labeling families. The conclusion is that only one of the product-specific
eco-labels examined here is reliable when examined in the light of all three stages. The main reason why multinationals establish
a product-specific eco-label instead of adopting one from an existing labeling family is that they want to profile themselves
as distinct from other companies. The unique character of a product-specific label creates a market opportunity for them. 相似文献
983.
Fushi Wen Ho Hyung Woo Elizabeth A. Pierson Toril D. Eldhuset C. G. Fossdal N. E. Nagy Martha C. Hawes 《Plant Molecular Biology Reporter》2009,27(1):58-68
Root cap development in cereals and legumes is self-regulated by a repressor that accumulates in the extracellular environment,
and immersing the root tip into water results in renewed cap development. By exploiting this phenomenon, root cap mitosis
and differentiation can be synchronously induced among populations. In Pisum sativum L., messenger RNA (mRNA) differential display revealed changes in expression of approximately 1% of the sample mRNA population
within minutes of induced cap turnover. This profile changes sequentially over a period of 30 min, then stabilizes. Microarray
analysis of Medicago truncatula root caps confirmed changes in expression of approximately 1% of the target population, within minutes. A cell specific marker
for cap turnover exhibited the same temporal and spatial expression profile in the gymnosperm species Norway spruce (Picea abies) as in pea. Induced cap development provides a means to profile cell-specific gene expression among phylogenetically diverse
species from the early moments of mitosis and cellular differentiation. 相似文献
984.
Seedlings of two barley genotypes (‘Maresi’ and wild form of Hordeum spontaneum) were treated with jasmonic acid (JA 5 μM and 15 μM) for 24 h, and then subjected to water stress (PEG 6000 solution of −
1.5 MPa). JA caused an increase in the content of ABA but not in that of proline and spermidine in the two studied genotypes.
The effect of the treatment did not depend on the applied JA concentration. The pre-stress treatment with JA changed plant
response to water deficit with regard to membrane injury. Treatment with a lower JA concentration (5 μM) caused a substantial
reduction of the stress-induced membrane damage in the both genotypes. A higher JA concentration (15 μM) caused the reduction
of membrane injury only in H. spontaneum and was ineffective in ‘Maresi’. JA had no influence on the leaf water status in water-stressed plants. A possible role of
JA in leaf ABA accumulation and alleviation of cell membrane injury under water deficit is discussed.
The work was partly supported by the Polish Committee For Scientific Research, grant No 5 PO6A 036 18 相似文献
985.
986.
Aims
The present study was planned to investigate the diversity of 1-aminocyclopropane-1-carboxylate (ACC) deaminase producing bacteria from the rhizosphere of wheat plants and subsequent evaluation of selected PGPR on growth enhancement of wheat seedlings under drought and saline conditions.Methods
ACC deaminase producing plant growth promoting rhizobacteria (PGPR) were isolated from the rhizosphere of wheat and identified using 16S rRNA gene sequence analysis. Isolates were evaluated for various direct and indirect plant growth promoting (PGP) traits. Plant inoculation experiment was conducted using isolates IG 19 and IG 22 in wheat to assess their plant growth promotion potential under salinity and drought stress.Results
Thirty-eight ACC deaminase producing PGPR were isolated which belonged to 12 distinct genera and falling into four phyla γ-proteobacteria, β-proteobacteria, Flavobacteria and Firmicutes. Klebsiella sp. was the most abundant genera and followed by Enterobacter sp. The isolates exhibited ACC deaminase activities ranging from 0.106–0.980 μM α- ketobutyrate μg protein?1 h?1. The isolates showed multiple PGP traits such as IAA production, phosphate, zinc, potassium solubilization and siderophore production. Enterobacter cloacae (IG 19) and Citrobacter sp. (IG 22) inoculated wheat seedlings showed notable increases in fresh and dry biomass under non-stress as well as under stressed condition.Conclusion
To the best of our knowledge this is the first report of presence of ACC deaminase activity and other PGP traits from the genus Citrobacter and Empedobacter. Our finding revealed that the γ-proteobacteria group dominated the wheat rhizosphere. Plant inoculation with PGPR could be a sustainable approach to alleviate abiotic stresses in wheat plants. These native PGPR isolates could be used as potential biofertilizers for sustainable agriculture.987.
Quinn Grundy Lisa Tierney Christopher Mayes Wendy Lipworth 《Journal of bioethical inquiry》2017,14(4):541-553
Conflicts of interest, stemming from relationships between health professionals and the pharmaceutical industry, remain a highly divisive and inflammatory issue in healthcare. Given that most jurisdictions rely on industry to self-regulate with respect to its interactions with health professionals, it is surprising that little research has explored industry leaders’ understandings of conflicts of interest. Drawing from in-depth interviews with ten pharmaceutical industry leaders based in Australia, we explore the normalized and structural management of conflicts of interest within pharmaceutical companies. We contrast this with participants’ unanimous belief that the antidote to conflicts of interest with health professionals were “informed consumers.” It is, thus, unlikely that a self-regulatory approach will be successful in ensuring ethical interactions with health professionals. However, the pharmaceutical industry’s routine and accepted practices for disclosing and managing employees’ conflicts of interest could, paradoxically, serve as an excellent model for healthcare. 相似文献
988.
Graft-versus-host disease (GVHD) induced by host antigen-presenting cells (APCs) and donor-derived T cells remains the major limitation of allogeneic bone marrow transplantation (allo-BMT). Notch signaling pathway is a highly conserved cell-cell communication that is important in T cell development. Recently, Notch signaling pathway is reported to be involved in regulating GVHD. To investigate the role of Notch inhibition in modulating GVHD, we established MHC-mismatched murine allo-BMT model. We found that inhibition of Notch signaling pathway by γ-secretase inhibitor in vivo could reduce aGVHD, which was shown by the onset time of aGVHD, body weight, clinical aGVHD scores, pathology aGVHD scores, and survival. Inhibition of Notch signaling pathway by DAPT ex vivo only reduced pathology aGVHD scores in the liver and intestine and had no impact on the onset time and clinical aGVHD scores. We investigated the possible mechanism by analyzing the phenotype of host APCs and donor-derived T cells. Notch signaling pathway had a broad effect on both host APCs and donor-derived T cells. The expressions of CD11c, CD40, and CD86 as the markers of activated dendritic cells (DCs) were decreased. The proliferative response of CD8+ T cell decreased, while CD4+ Notch-deprived T cells had preserved expansion with increased expressions of CD25 and Foxp3 as markers of regulatory T cells (Tregs). In conclusion, Notch inhibition may minimize aGVHD by decreasing proliferation and activation of DCs and CD8+ T cells while preserving Tregs expansion. 相似文献
989.
Genome editing is a powerful technology that can efficiently alter the genome of organisms to achieve targeted modification of endogenous genes and targeted integration of exogenous genes. Current genome-editing tools mainly include ZFN, TALEN and CRISPR/Cas9, which have been successfully applied to all species tested including zebrafish, humans, mice, rats, monkeys, pigs, cattle, sheep, goats and others. The application of genome editing has quickly swept through the entire biomedical field, including livestock breeding. Traditional livestock breeding is associated with rate limiting issues such as long breeding cycle and limitations of genetic resources. Genome editing tools offer solutions to these problems at affordable costs. Generation of gene-edited livestock with improved traits has proven feasible and valuable. For example, the CD163 gene-edited pig is resistant to porcine reproductive and respiratory syndrome (PRRS, also referred to as “blue ear disease”), and a SP110 gene knock-in cow less susceptible to tuberculosis. Given the high efficiency and low cost of genome editing tools, particularly CRISPR/Cas9, it is foreseeable that a significant number of genome edited livestock animals will be produced in the near future; hence it is imperative to comprehensively evaluate the pros and cons they will bring to the livestock breeding industry. Only with these considerations in mind, we will be able to fully take the advantage of the genome editing era in livestock breeding. 相似文献
990.
Biswas R Yamaoka M Nakayama H Kondo T Yoshida K Bisaria VS Kondo A 《Applied microbiology and biotechnology》2012,94(3):651-658
Production of 2,3-butanediol by Bacillus subtilis takes place in late-log or stationary phase, depending on the expression of bdhA gene encoding acetoin reductase, which converts acetoin to 2,3-butanediol. The present work focuses on the development of
a strain of B. subtilis for enhanced production of 2,3-butanediol in early log phase of growth cycle. For this, the bdhA gene was expressed under the control of P
alsSD
promoter of AlsSD operon for acetoin fermentation which served the substrate for 2,3-butanediol production. Addition of acetic acid in the
medium induced the production of 2,3-butanediol by 2-fold. Two-step aerobic–anaerobic fermentation further enhanced 2,3-butanediol
production by 4-fold in comparison to the control parental strain. Thus, addition of acetic acid and low dissolved oxygen
in the medium are involved in activation of bdhA gene expression from P
alsSD
promoter in early log phase. Under the conditions tested in this work, the maximum production of 2,3-butanediol, 2.1 g/l
from 10 g/l glucose, was obtained at 24 h. Furthermore, under the optimized microaerophilic condition, the production of 2,3-butanediol
improved up to 6.1 g/l and overall productivity increased by 6.7-fold to 0.4 g/l h in the engineered strain compared to that
in the parental control. 相似文献