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151.
Emission of Plutella xylostella-induced compounds from cabbages grown at elevated CO2 and orientation behavior of the natural enemies 下载免费PDF全文
Several plant species defend themselves indirectly from herbivores by producing herbivore-induced volatile compounds that attract the natural enemies of herbivores. Here we tested the effects of elevated atmospheric CO(2) (720 micromol mol(-1)) concentration on this indirect defense, physiological properties, and constitutive and induced emissions of white cabbage (Brassica oleracea ssp. capitata, cvs Lennox and Rinda). We monitored the orientation behavior of the generalist predator Podisus maculiventris (Heteroptera: Pentatomidae) and the specialist parasitoid Cotesia plutellae (Hymenoptera: Braconidae) to plants damaged by Plutella xylostella (Lepidoptera: Plutellidae) in the Y-tube olfactometer. Elevated CO(2) levels did not affect stomatal densities but reduced specific leaf area and increased leaf thickness in cv Lennox. In addition to enhanced constitutive monoterpene emission, P. xylostella-damaged cabbages emitted homoterpene (E)-4,8-dimethyl-1,3,7-nonatriene, sesquiterpene (E,E)-alpha-farnesene, and (Z)-3-hexenyl acetate. Growth at elevated CO(2) had no significant effect on the emissions expressed per leaf area, while minor reduction in the emission of homoterpene (E)-4,8-dimethyl-1,3,7-nonatriene and (E,E)-alpha-farnesene was observed at elevated CO(2) in one of two experiments. The generalist predator P. maculiventris discriminated only between the odors of intact and P. xylostella-damaged cv Rinda plants grown at ambient CO(2) concentration, preferring the odor of the damaged plants. The specialist parasitoid C. plutellae preferred the odor of damaged plants of both cultivars grown at ambient CO(2) but did not detect damaged cv Lennox plants grown at elevated CO(2). The results suggest that elevated atmospheric CO(2) concentration could weaken the plant response induced by insect herbivore feeding and thereby lead to a disturbance of signaling to the third trophic level. 相似文献
152.
153.
Gürlek A Aydoğan H Aşkar I 《Plastic and reconstructive surgery》2004,114(1):263; author reply 263-263; author reply 264
154.
Effects of a GnRH agonist on oocyte number and maturation in mice superovulated with eCG and hCG 总被引:4,自引:0,他引:4
The objective was to investigate the effects of a gonadotropin-releasing hormone agonist (GnRH) on ovulation rate and the number and maturation of oocytes in mice superovulated with equine chorionic gonadotropin (eCG) and human chorionic gonadotropin (hCG). Thirty 3-month-old BALB/C female mice (weight: 25-30 g) were assigned to three experimental groups: control, superovulated, and superovulated with GnRH pretreatment (n=10 per group). Control mice received an i.p. injection of 0.1 ml physiological saline solution. Superovulation was induced with 5 IU eCG (i.p.) and 5 IU hCG 48 h later. Mice in the superovulated with GnRH pretreatment group were given GnRH (20 mg/kg Fertirelin, i.m.), 24 h before superovulation. Thirteen hours after hCG administration, mice were sacrificed by cervical dislocation and blood samples were collected to determine serum progesterone concentration (by radioimmunoassay). Ovaries and oviducts were also harvested to enumerate corpora lutea and cumulus-enclosed oocytes. Progesterone concentrations were not significantly different among groups. The oocyte number and the maturation, ovulation rate, and the number of corpora lutea were higher in GnRH-treated mice than both controls and superovulated mice. In conclusion, GnRH given 24 h before superovulation with eCG-hCG increased the number and maturation of oocytes and the rate of ovulation in mice. 相似文献
155.
Elzein E Ibrahim P Koltun DO Rehder K Shenk KD Marquart TA Jiang B Li X Natero R Li Y Nguyen M Kerwar S Chu N Soohoo D Hao J Maydanik VY Lustig DA Zeng D Leung K Zablocki JA 《Bioorganic & medicinal chemistry letters》2004,14(24):6017-6021
New inhibitors of palmitoyl-CoA oxidation are based on the introduction of nitrogen heterocycles in the ‘Western Portion’ of the molecule. SAR studies led to the discovery of CVT-4325 (shown), a potent FOXi (IC50 = 380 nM rat mitochondria) with favorable PK properties (F = 93%, t1/2 = 13.6 h, dog). 相似文献
156.
Mutations in the Connexin-26 (specified GJB2) gene have been shown to be a major cause of nonsyndromic recessive deafness (NSRD), and a single mutation 35delG in the GJB2 gene accounts for the majority of cases of NSRD. For diagnostic analyses and for scientific studies of large numbers of patients, fast and economic assays that can be performed with standard polymerase chain reaction (PCR) instruments are highly desirable. We have developed an allele-specific amplification (ASA)-based restriction fragment length polymorphism (RFLP) assay. We evaluated the multiplex method for its ability to 35delG mutation. Our method is a stable, reproducible and concordend with previously reported PCR-RFLP assays. 相似文献
157.
Möller S Koczan D Serrano-Fernandez P Zettl UK Thiesen HJ Ibrahim SM 《In silico biology》2004,4(4):417-427
Common complex polygenic diseases as autoimmune diseases have not been completely understood on a molecular level. While many genes are known to be involved in the pathways responsible for the phenotype, explicit causes for the susceptibility of the disease remain to be elucidated. The susceptibility to disease is thought to be the result of genetic epistatic interactions between common polymorphic genes. This polymorphism is mostly caused by single nucleotide polymorphisms (SNPs). Human subpopulations are known to differ in the susceptibility to the diseases and generally in the distribution of single nucleotide polymorphisms. The here presented approach retrieves SNPs with the most divergent frequencies for selected human subpopulations to help defining properties for the experimental verification of SNPs within defined regions. A web-accessible program implementing this approach was evaluated for multiple sclerosis (MS), a common human polygenic disease. A link to a summary of data from "The SNP Consortium" (TSC) with sex-dependencies of SNPs is available. Associations of SNPs to genes, genetic markers and chromosomal loci are retrieved from the Ensembl project. This tool is recommended to be used in conjunction with microarray analyses or marker association studies that link genes or chromosomal loci to particular diseases. 相似文献
158.
A rapid and effective method of extracting fully intact RNA from thermophilic geobacilli that is suitable for gene expression analysis 总被引:4,自引:0,他引:4
Extraction of intact RNA is essential for quantitative gene expression analysis. Isolating high quality RNA from gram-positive bacteria is known to be problematic particularly from organisms that have optimal growth temperatures greater than 45 °C. We report a novel extraction protocol for the rapid isolation of fully intact RNA from thermophilic Geobacillus thermoleovorans using a lysing matrix containing a mixture of ceramic and glass beads, triisopropylnaphthalene sulfonic acid (TNS), and p-4-aminosalicyclic acid (PAS). Combining both detergents, TNS and PAS, appeared to increase denaturation of RNases at thermophilic temperatures. Gel electrophoresis revealed that only RNA isolated using the TNS-PAS procedure demonstrated sharp, undegraded 23S, 16S, and 5S ribosomal RNA bands. RNA extracted from geobacilli using commercially available kits was extensively degraded and was not suitable for detecting gene expression. Total RNA yields extracted with the TNS-PAS protocol were greater than eightfold higher than those obtained with available kits. Critically, it was also shown that only RNA isolated with the TNS-PAS-based method was suitable for monitoring thermophile gene expression patterns using RT-PCR analysis.Communicated by G. Antranikian 相似文献
159.
Background
Flavonoids, one of the major groups of secondary metabolites, play important roles in the physiology, ecology and defence of plants. Their wide range of activities is the result of their structural diversity that encompasses a variety of functional group substitutions including hydroxylations. The aromatic hydroxylation at position 6 of flavonols is of particular interest, since it is catalyzed by a 2-oxoglutarate-dependent dioxygenase (ODD), rather than a cytochrome P450-dependent monooxygenase. ODDs catalyze a variety of enzymatic reactions implicated in secondary metabolite biosynthesis. 相似文献160.