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101.
Lange KH Isaksson F Juul A Rasmussen MH Bülow J Kjaer M 《American journal of physiology. Endocrinology and metabolism》2000,279(5):E989-E996
The present study investigated whether recombinant human (rh) growth hormone (GH) combined with endurance training would have a larger effect on oxidative capacity, metabolism, and body fat than endurance training alone. Sixteen healthy, elderly women, aged 75 yr, performed closely monitored endurance training on a cycle ergometer over 12 wk. rhGH was given in a randomized, double-blinded, placebo-controlled design in addition to the training program. GH administration resulted in a doubling of serum insulin-like growth factor I levels. With endurance training, peak oxygen uptake increased by approximately 18% in both groups, whereas the marked increase in muscle citrate synthase activity was 50% larger in the GH group compared with the placebo group. In addition, only the GH group revealed an increase in muscle L-3-hydroxyacyl-CoA dehydrogenase activity. Body weight remained unchanged in both groups, but the GH group showed significant changes in body composition with a decrease in fat mass and an increase in lean body mass. Twenty-four-hour indirect calorimetry performed in four subjects showed a marked increase in energy expenditure with increased relative and absolute fat combustion in the two subjects receiving rhGH. In conclusion, rhGH adds to the effects of endurance training on muscle oxidative enzymes and causes a reduction in body fat in elderly women. 相似文献
102.
Protoplasts of an accession of Isatis indigotica Fort. were isolated from mesophyll tissue by enzymatic digestion and cultured
using a feeder cell system. Shoot regeneration efficiency was 100% via organogenesis among 627 isolated calluses within 30–37
days. Among these shoot initiating calluses, 162 (22.6%) developed normal shoots with multiple (2–5) shoots per callus. The
remaining calluses developed only vitreous shoots. High concentration (5 μM) of indole-3-butyric acid had a positive effect
on rooting compared to low concentration (0.5 μM) of indole-3-butyric acid and α-naphthalene-acetic acid. The average rooting
efficiency of regenerated shoots of two experiments was higher on LS medium with 5 μM indole-3-butyric acid than on LS medium
without growth regulators. Twenty-nine plantlets, with 2–3 expanded leaves and roots were potted in soil and 22 developed
normally to maturity in the glasshouse.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
103.
Phloem exudates were collected along the tree axis at differentheights of wild type and transgenic poplar. Over-expressionof bacterial 相似文献
104.
Claire Lurin Lise Jouanin 《Molecular breeding : new strategies in plant improvement》1995,1(4):411-417
A novel method for studying differential expression of multigene family members based on the high sensitivity of RT-PCR completed by restriction site polymorphism of DNA is described. This method allows the identification of specific patterns of expression of fourchalcone synthase genes in a Hunnegem poplar clone (Populus trichocarpa ×Populus deltoides). 相似文献
105.
Brandon T. Hassett Anne‐Lise L Ducluzeau Roy E. Collins Rolf Gradinger 《Environmental microbiology》2017,19(2):475-484
Fungi are important parasites of primary producers and nutrient cyclers in aquatic ecosystems. In the Pacific‐Arctic domain, fungal parasitism is linked to light intensities and algal stress that can elevate disease incidence on algae and reduce diatom concentrations. Fungi are vastly understudied in the marine realm and knowledge of their function is constrained by the current understanding of fungal distribution and drivers on global scales. To investigate the spatial distribution of fungi in the western Arctic and sub‐Arctic, we used high throughput methods to sequence 18S rRNA, cloned and sequenced 28S rRNA and microscopically counted chytrid‐infected diatoms. We identified a broad distribution of fungal taxa predominated by Chytridiomycota and Dikarya. Phylogenetic analysis of our Chytridiomycota clones placed Arctic marine fungi sister to the order Lobulomycetales. This clade of fungi predominated in fungal communities under ice with low snowpack. Microscopic examination of fixed seawater and sea ice samples revealed chytrids parasitizing diatoms collected across the Arctic that notably infected 25% of a single diatom species in the Bering Sea. The Pezizomycotina comprised > 95% of eukaryotic sequence reads in Greenland, providing preliminary evidence for osmotrophs being a substitute for algae as the base of food webs. 相似文献
106.
Lise Stengård Hansen 《BioControl》1988,33(1):33-42
The phytoseiid miteAmblyseius barkeri (Hughes) (=Amblyseius mckenziei Sch. & Pr.) was used for biological control ofThrips tabaci Lind. in 7 commercial glasshouses with cucumber (a total of 5780 m2). Predatory mites were introduced 3–4 times in densities ranging from 40 to 300/m2 at each release. In 6 of the 7 glasshouses, control of thrips was satisfactory throughout the growing season. Thrips densities
were kept below 15 individuals per leaf. In 1 glasshouse, thrips damage was seen on the fruits at densities of 25 thrips per
leaf, but the thrips population was quickly reduced and remained at low densities for the next 3 months.
相似文献
107.
Marchais-Oberwinkler S Nowicki B Pike VW Halldin C Sandell J Chou YH Gulyas B Brennum LT Farde L Wikström HV 《Bioorganic & medicinal chemistry》2005,13(3):883-893
WAY-100635 [N-(2-(1-(4-(2-methoxyphenyl)piperazinyl)ethyl))-N-(2-pyridinyl)cyclohexanecarboxamide] 1 and its O-desmethyl derivative DWAY 2 are well-known high affinity 5-HT(1A) receptor antagonists, which when labeled with carbon-11 (beta+; t(1/2) = 20.4 min) in the carbonyl group are effective radioligands for imaging brain 5-HT(1A) receptors with positron emission tomography (PET). In a search for new 5-HT(1A) antagonists with different pharmacokinetic and metabolic properties, the pyridinyl N-oxide moiety was incorporated into analogs of 1 and 2. NOWAY 3, in which the pyridinyl ring of 1 was oxidized to the pyridinyl N-oxide, was prepared via nucleophilic substitution of 2-[4-(2-methoxyphenyl)piperazin-1-yl]ethylamine on 2-chloropyridine-N-oxide followed by acylation with cyclohexanecarbonyl chloride. 6Cl-NOWAY 4, a more lipophilic (pyridinyl-6)-chloro derivative of 3, was prepared by treating 1-(2-methoxyphenyl)-4-(2-(2-(6-bromo)aminopyridinyl-N-oxide)ethyl)piperazine with cyclohexanecarbonyl chloride for acylation and concomitant chloro for bromo substitution. NEWWAY 5, in which the 2-hydroxy-phenyl group of 2 is replaced with a 2-pyridinyl N-oxide group with the intention of mimicking the topology of 2, was prepared in five steps from 2-(chloroacetylamino)pyridine. N-Oxides 3-5 were found to be high affinity antagonists at 5-HT(1A) receptors, with 3 having the highest affinity and a Ki value (0.22 nM) comparable to that of 1 (0.17 nM). By calculation the lipophilicity of 3 (LogP = 1.87) is lower than that of 1 by 1.25 LogP units while TLC and reverse phase HPLC indicate that 3 has slightly lower lipophilicity than 1. On the basis of these encouraging findings, the N-oxide 3 was selected for labeling with carbon-11 in its carbonyl group and for evaluation as a radioligand with PET. After intravenous injection of [carbonyl-11C]3 into cynomolgus monkey there was very low uptake of radioactivity into brain and no PET image of brain 5-HT(1A) receptors was obtained. Either 3 inadequately penetrates the blood-brain barrier or it is excluded from brain by an active efflux mechanism. Rapid deacylation of 3 was not apparent in vivo; in cynomolgus monkey plasma radioactive metabolites of [carbonyl-11C]3 appeared less rapidly than from the radioligands [carbonyl-11C]1 and [carbonyl-11C]2, which are known to be primarily metabolized by deacylation. Ligand 3 may have value as a new pharmacological tool, but not as a radioligand for brain imaging. 相似文献
108.
Nutritional regulation of bile acid metabolism is associated with improved pathological characteristics of the metabolic syndrome 总被引:1,自引:0,他引:1
109.
110.
Dragosits M Frascotti G Bernard-Granger L Vázquez F Giuliani M Baumann K Rodríguez-Carmona E Tokkanen J Parrilli E Wiebe MG Kunert R Maurer M Gasser B Sauer M Branduardi P Pakula T Saloheimo M Penttilä M Ferrer P Luisa Tutino M Villaverde A Porro D Mattanovich D 《Biotechnology progress》2011,27(1):38-46
Microorganisms encounter diverse stress conditions in their native habitats but also during fermentation processes, which have an impact on industrial process performance. These environmental stresses and the physiological reactions they trigger, including changes in the protein folding/secretion machinery, are highly interrelated. Thus, the investigation of environmental factors, which influence protein expression and secretion is still of great importance. Among all the possible stresses, temperature appears particularly important for bioreactor cultivation of recombinant hosts, as reductions of growth temperature have been reported to increase recombinant protein production in various host organisms. Therefore, the impact of temperature on the secretion of proteins with therapeutic interest, exemplified by a model antibody Fab fragment, was analyzed in five different microbial protein production hosts growing under steady-state conditions in carbon-limited chemostat cultivations. Secretory expression of the heterodimeric antibody Fab fragment was successful in all five microbial host systems, namely Saccharomyces cerevisiae, Pichia pastoris, Trichoderma reesei, Escherichia coli and Pseudoalteromonas haloplanktis. In this comparative analysis we show that a reduction of cultivation temperature during growth at constant growth rate had a positive effect on Fab 3H6 production in three of four analyzed microorganisms, indicating common physiological responses, which favor recombinant protein production in prokaryotic as well as eukaryotic microbes. 相似文献