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991.
In humans, susceptibility to several immunopathologic diseases maps to a conserved block encompassing the polymorphic BAT1, NFKBIL1 (IKBL) and TNF genes in the central MHC. As a pre-requisite for studies of these genes in animal models, we characterized Bat1a and Nfkbil1 in inbred mice differing in their H2 haplotype. We identified two indels and nine single nucleotide polymorphisms (SNP) upstream of Nfkbil1, one indel, nine SNP upstream of Bat1a and a synonymous SNP in exon 2 of Bat1a. H2(g7) and H2(b) mice yielded identical Bat1a and Nfkbil1 sequences. Real time PCR (RT-PCR) showed Bat1a was expressed in adult brain, heart, kidney, liver, lung, pancreas and spleen. Expression of Bat1a was higher in brain and liver of 15-day embryos compared to 1-day old mice and increased moderately in liver and lung of adult mice 2-4 h after LPS challenge. Nfkbil1 expression was low or undetetectable in all tissues and cell lines.  相似文献   
992.
Summary Interactions of 46 isolates of fungi with an isolate ofM. phaseoli from cotton, was studied in agar culture. They were grouped into 4 different types of reactions.T. viride was found to inhibit the growth ofM. phaseoli and grow over its colony. The hyphae ofT. viride were observed to coil around the hyphae ofM. phaseoli. A majority of the isolates tested had no effect on the growth ofM. phaseoli. M. phaseoli, however, was found to overgrow the test fungi.  相似文献   
993.
The inhibitory role of AgNO3 on glucose‐mediated respiration in Escherichia coli has been investigated as a function of pH and temperature using Clark‐type electrode, environmental scanning electron microscopy, and computational tools. In the given concentration of bacterial suspension (1 × 108 CFU/ml), E. coli showed an increasing nonlinear trend of tetra‐phasic respiration between 1–133 μM glucose concentration within 20 min. The glucose concentrations above 133 μM did not result any linear increment in respiration but rather showed a partial inhibition at higher glucose concentrations (266–1066 μM). In the presence of glucose, AgNO3 caused a concentration‐dependent (47–1960 μM) inhibition of the respiration rate within 4 min of its addition. The respiration rate was the highest at pH 7–8 and then was decreased on either side of this pH range. The inhibitory action of AgNO3 upon bacterial respiration was the highest at 37 °C. The observations of the respiration data were well supported by the altered bacterial morphology as observed in electron microscopic study. Docking study indicated the AgNO3 binding to different amino acids of all respiratory complex enzymes in E. coli and thereby explaining its interference with the respiratory chain. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
994.
Behavioural responses of Helicoverpa armigera egg parasitoid, Trichogramma chilonis and the larval parasitoid, Campoletis chlorideae towards the leaves of groundnut (Arachis hypogaea) genotypes (ICGV 86699, ICGV 86031, ICG 2271, and ICG 1697-resistant, and the susceptible check-JL 24) were studied by using a Y-tube olfactometer. Orientation was studied in comparison to clean air, to insect resistant genotypes in relation to JL 24 and towards H. armigera damaged and undamaged leaves. Leaves of ICGV 86699, ICGV 86031 and ICG 2271 were more attractive to T. chilonis adults than to the clean air. They were strongly attracted to the leaves of ICGV 86699, ICGV 86031 and ICG 1697 than of JL 24. Insect damaged leaves of ICGV 86699, ICGV 86031 and ICG 1697 were more attractive than the respective uninfested leaves. C. chlorideae showed greater attraction towards leaves of ICGV 86699, ICG 2271 and ICG 1697 than the clean air, and were more attracted towards leaves of ICGV 86699 and ICGV 86031 than those of JL 24. The damaged leaves of ICGV 86699, ICGV 86031 and ICG 2271 were more attractive to C. chlorideae than the respective uninfested leaves. Thus insect resistant genotypes exhibited greater compatibility with the natural enemies in groundnut.  相似文献   
995.
The edible red alga Porphyra yezoensis is among the most popular marine algae and is of economic and medicinal importance. In the present study, the neurotrophic and neuroprotective activities of the ethanol extract of P. yezoensis (PYE) were investigated in primary cultures of hippocampal neurons. Results revealed that PYE significantly increased neurite outgrowth at an optimal concentration of 15 µg/mL. PYE dose-dependently increased viable cells, significantly accelerated the rate of neuronal differentiation in cultures, promoted axodendritic arborization, and eventually induced synaptogenesis. In addition to morphological development, PYE also promoted functional maturation as indicated by the staining of live cultures with FM 1–43. Moreover, PYE increased neuronal survivability, which was attributed to reduced apoptosis and its ROS scavenging activity. Taurine, a major organic acid in PYE (2.584/100 mg of dry PYE) promoted neurite outgrowth in a dose-dependent manner, and this promotion was suppressed by the taurine antagonist isethionic acid. The study indicates that PYE and its active component, taurine, facilitate neuronal development and maturation and have a neuroprotective effect.  相似文献   
996.
Interaction of a tyrosine kinase inhibitor, vandetanib (VDB), with the major transport protein in the human blood circulation, human serum albumin (HSA), was investigated using fluorescence spectroscopy, circular dichroism (CD) spectroscopy, and molecular docking analysis. The binding constant of the VDB–HSA system, as determined by fluorescence quenching titration method was found in the range, 8.92–6.89?×?103?M?1 at three different temperatures, suggesting moderate binding affinity. Furthermore, decrease in the binding constant with increasing temperature revealed involvement of static quenching mechanism, thus affirming the formation of the VDB–HSA complex. Thermodynamic analysis of the binding reaction between VDB and HSA yielded positive ΔS (52.76 J?mol?1 K?1) and negative ΔH (?6.57?kJ?mol?1) values, which suggested involvement of hydrophobic interactions and hydrogen bonding in stabilizing the VDB–HSA complex. Far-UV and near-UV CD spectral results suggested alterations in both secondary and tertiary structures of HSA upon VDB-binding. Three-dimensional fluorescence spectral results also showed significant microenvironmental changes around the Trp residue of HSA consequent to the complex formation. Use of site-specific marker ligands, such as phenylbutazone (site I marker) and diazepam (site II marker) in competitive ligand displacement experiments indicated location of the VDB binding site on HSA as Sudlow’s site I (subdomain IIA), which was further established by molecular docking results. Presence of some common metal ions, such as Ca2+, Zn2+, Cu2+, Ba2+, Mg2+, and Mn2+ in the reaction mixture produced smaller but significant alterations in the binding affinity of VDB to HSA.  相似文献   
997.
BackgroundChilo partellus is an important insect pest infesting sorghum and maize. The larvae internalize in the stem, rendering difficulties in pest management. We investigated the effects of Capsicum annuum proteinase inhibitors (CanPIs) on C. partellus larvae by in-vitro and in-vivo experiments.MethodsRecombinant CanPI-7 (with four-Inhibitory Repeat Domains, IRDs), -22 (two-IRDs) and insect proteinase activities were estimated by proteinase assays, dot blot assays and in gel activity assays. Feeding bioassays of lab reared C. partellus with CanPI-7 and -22 were performed. C. partellus proteinase gene expression was done by RT-PCR. In-silico structure prediction of proteinases and CanPI IRDs was carried out, their validation and molecular docking was done for estimating the interaction strength.ResultsLarval proteinases of C. partellus showed higher activity at alkaline pH and expressed few proteinase isoforms. Both CanPIs showed strong inhibition of C. partellus larval proteinases. Feeding bioassays of C. partellus with CanPIs revealed a dose dependent retardation of larval growth, reduction of pupal mass and fecundity, while larval and pupal periods increased significantly. Ingestion of CanPIs resulted in differential up-regulation of C. partellus proteinase isoforms, which were sensitive to CanPI-7 but were insensitive to CanPI-22. In-silico interaction studies indicated the strong interaction of IRD-9 (of CanPI-22) with Chilo proteinases tested.ConclusionsOf the two PIs tested, CanPI-7 prevents induction of inhibitor insensitive proteinases in C. partellus so it can be explored for developing C. partellus tolerance in sorghum.General significanceIngestion of CanPIs, effectively retards C. partellus growth; while differentially regulating the proteinases.  相似文献   
998.
Thrips are one of the insect pests of persimmon (Diospyros kaki Thunb.) in the major production areas of astringent persimmon in Korea. We surveyed astringent persimmon orchards in the Damyang, Sangju and Cheongdo regions of Korea to determine thrips species composition and abundance. Orchards sprayed with either organic or conventional pesticides were sampled over the course of one flowering season, using yellow sticky traps to determine if this is a suitable method for monitoring thrips populations, and to determine thrips species composition and abundance. Eight thrips species were captured on yellow sticky traps in both the tree canopy and ground cover: Ponticulothrips diospyrosi Haga et Okajima, Scirtothrips dorsalis (Hood), Frankliniella occidentalis (Pergande), F. intonsa (Trybom), Thrips tabaci (Lindeman), T. hawaiiensis (Morgan), T. coloratus (Schmutz) and T. palmi (Karny). In all regions, F. occidentalis and F. intonsa dominated in both organic and conventional orchards. S. dorsalis, F. occidentalis, F. intonsa and T. hawaiiensis were found in persimmon flowers, with S. dorsalis the dominant thrips. Significantly more S. dorsalis were captured from flowers in the lower and middle canopy than in flowers from the upper canopy. Fruit damage was also significantly higher in fruit from the lower canopy than in fruit from the middle and upper canopy.  相似文献   
999.
Despite the well‐recognized merits of simultaneous saccharification and co‐fermentation (SSCF) on relieving sugar product inhibition on cellulase activity, a practical concomitance difficulty of xylose with inhibitors in the pretreated lignocellulose feedstock prohibits the essential application of SSCF for cellulosic ethanol fermentation. To maximize the SSCF potentials for cellulosic ethanol production, a dry biorefining approach was proposed starting from dry acid pretreatment, disk milling, and biodetoxification of lignocellulose feedstock. The successful SSCF of the inhibitor free and xylose conserved lignocellulose feedstock after dry biorefining reached a record high ethanol titer at moderate cellulase usage and minimum wastewater generation. For wheat straw, 101.4 g/L of ethanol (equivalent to 12.8% in volumetric percentage) was produced with the overall yield of 74.8% from cellulose and xylose, in which the xylose conversion was 73.9%, at the moderate cellulase usage of 15 mg protein per gram cellulose. For corn stover, 85.1 g/L of ethanol (equivalent to 10.8% in volumetric percentage) is produced with the overall conversion of 84.7% from cellulose and xylose, in which the xylose conversion was 87.7%, at the minimum cellulase usage of 10 mg protein per gram cellulose. Most significantly, the SSCF operation achieved the high conversion efficiency by generating the minimum amount of wastewater. Both the fermentation efficiency and the wastewater generation in the current dry biorefining for cellulosic ethanol production are very close to that of corn ethanol production, indicating that the technical gap between cellulosic ethanol and corn ethanol has been gradually filled by the advancing biorefining technology.  相似文献   
1000.

Background

Zinc (Zn) deficiency is one of the most important micronutrient disorders affecting human health. Wheat is the staple food for 35% of the world’s population and is inherently low in Zn, which increases the incidence of Zn deficiency in humans. Major wheat-based cropping systems viz. rice–wheat, cotton–wheat and maize–wheat are prone to Zn deficiency due to the high Zn demand of these crops.

Methods

This review highlights the role of Zn in plant biology and its effect on wheat-based cropping systems. Agronomic, breeding and molecular approaches to improve Zn nutrition and biofortification of wheat grain are discussed.

Results

Zinc is most often applied to crops through soil and foliar methods. The application of Zn through seed treatments has improved grain yield and grain Zn status in wheat. In cropping systems where legumes are cultivated in rotation with wheat, microorganisms can improve the available Zn pool in soil for the wheat crop. Breeding and molecular approaches have been used to develop wheat genotypes with high grain Zn density.

Conclusions

Options for improving grain yield and grain Zn concentration in wheat include screening wheat genotypes for higher root Zn uptake and grain translocation efficiency, the inclusion of these Zn-efficient genotypes in breeding programs, and Zn fertilization through soil, foliar and seed treatments.
  相似文献   
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