Four strains of endophytic microorganisms isolated from carrot root were able to carry out the reduction of the carbonyl group with diverse degree of enantio-, and diasteroselectivity. Furthermore, biotransformation in the presence of bacterial inhibitor affects the stereochemical outcome of the reaction, and the concomitant addition of a yeast inhibitor results in a large decrease in the conversion percentage. These results indicate that endophytic microorganisms might be involved in the enantioselective reduction of ketones and ketoesters with fresh carrot root pieces. 相似文献
A hallmark of prion disease is the transformation of normal cellular prion protein (PrPc) into an infectious disease-associated
isoform, (PrPsc). Anti-prion protein monoclonal antibodies are invaluable for structure-function studies of PrP molecules.
Furthermore recent in vitro and in vivo studies indicate that anti-PrP monoclonal antibodies can prevent the incorporation of PrPc into propagating prions. 相似文献
In this study, transgenic mice in which membrane-linked enhanced green fluorescent protein (mGFP) is expressed from the Thy1.2 promoter were used. In these mice, a subpopulation of small to medium sized DRG neurons double stained for IB4 but not for CGRP. Most of the peripheral terminals traversed the dermis and ramify within the epidermis and form superficial terminals. Within the spinal cord, these afferents terminated exclusively within the substantia gelatinosa (SG). A second fibre type in the skin also expressed mGFP, and formed club-shaped endings towards the bases of hairs. Injury to the sciatic nerve resulted in mGFP loss from the SG ipsilateral to the nerve injury, but also in the corresponding region contralaterally. Together, these findings reveal the specificity of connectivity of a defined subpopulation of DRG sensory neurons innervating the epidermis and this will facilitate analysis of their physiological functions. 相似文献
One of the main issues in the development of new biocolonizable materials is to understand the influence of the synthetic material on the biological response in terms of cellular adhesion, proliferation, and differentiation. In this study, we characterized different polymeric materials (with different hydrophobicity/hydrophilicity ratios and electrical charges) using dynamic-mechanical analysis, equilibrium water content, and surface energy. Cell adhesion, viability, morphology, and proliferation studies were conducted with these materials using a conjunctival epithelial cell line (IOBA-NHC). The biological data regarding physicochemical parameters of the materials were also correlated. When conjunctival epithelial cells were grown on poly(ethyl acrylate-co-hydroxyethyl acrylate) copolymers, P(EA-co-HEA), samples with up to 20% hydrophilic groups on their polymeric chain showed adhesion, viability, and proliferation, although these three factors decreased as the hydrophilic group content increased. The poly(ethyl acrylate-co-methacrylic acid) 90/10 copolymer, P(EA-co-MAAc) 90/10, showed better results than poly(ethyl acrylate-co-hydroxyethyl acrylate) copolymers and were even better than tissue control polystyrene (TCPS). This feature is explained by the presence of electrical charges on the surface of the poly(ethyl acrylate-co-methacrylic acid) 90/10 copolymer. The fact that the ionic groups are configured in domains structured in nanophases as happens in this copolymer improves cell adhesion even further. 相似文献
Fragrant rice is popular for the good grain quality and special aroma. The present study conducted a field experiment to investigate the effects of ultrasonic seed treatment on grain yield, quality characters, physiological properties and aroma biosynthesis of different fragrant rice genotypes. The seeds of three fragrant rice genotypes were exposed to 1 min of ultrasonic vibration and then cultivated in paddy field. The results of present study showed that ultrasonic seed treatment increased grain yield of all fragrant rice genotypes but the responses of yield formation to ultrasonic were varied with different genotypes. Compared with control, ultrasonic seed treatment increased grain 2-acetyl-1-pyrroline (2-AP, the key component of fragrant rice aroma) content by 13.40%–44.88%. Ultrasonic seed treatment also reduced the crude protein contents in grains. The head rice rate, rice length, chalky rice rate, and chalkiness degree were influenced by ultrasonic for one or two fragrant rice genotypes. The activities of peroxidase and superoxide dismutase were also enhanced due to ultrasonic seed treatment. In conclusion, ultrasonic seed treatment increased grain, regulated grain aroma and quality, and improved stress resistance of fragrant rice varieties. 相似文献
This study evaluated the effects of foliar spraying melatonin (MT) on the growth of salt-stressed rice. Seedlings were treated with 50 and 100 mM of NaCl and different concentrations of MT (25, 50, 100, 200, 300, and 400 μM) for 14 days. Different concentrations of MT could promote plant growth significantly under salt stress, particularly at concentrations of 200, 300, and 400 μM. A concentration of 200 μM MT was considered as optimal and used in a subsequent experiment on biomass, water content, antioxidation, mineral nutrition, salt absorption, and distribution of salt-stressed rice seedlings. Results showed that MT’s promoting effect on plant growth under salt stress was evident with time, particularly under high salt stress. MT improved the activities of antioxidant enzymes, reduced membrane lipid peroxidation, alleviated cell injury in plant leaves, and increased N content and Si accumulation in the leaves and roots under salt stress, particularly under high salinity. This compound also inhibited Na uptake and upward transport, but it promoted or maintained the uptake and upward transport of K and Ca in salt-stressed rice. Thus, MT improved the ion homeostasis of K/Na and Ca/Na in plants, particularly in the leaves. Foliar spraying of MT alleviated salt stress on rice by promoting nutrient accumulation or translocation, improving ion homeostasis, which is evident in the leaves, and consequently enhancing its salt resistance. The antioxidative improvement caused by MT might also be related to the improved ion homeostasis.