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Jacek Kęsy Beata Maciejewska Magdalena Sowa Magdalena Szumilak Krzysztof Kawałowski Maja Borzuchowska Jan Kopcewicz 《Plant Growth Regulation》2008,55(1):43-50
It has been shown that both IAA and ethylene application inhibit flower induction in the short-day plant Pharbitis nil. However application of IAA has elevated ethylene production in this plant, as well. Strong enhancement of ethylene production
is also correlated with the night-break effect, which completely inhibits flowering. In order to determine what the role of
IAA and ethylene is in the photoperiodic flower induction in Pharbitis nil, we measured changes in their levels during inductive and non-inductive photoperiods, and the effects of ethylene biosynthesis
and action inhibitors on inhibition of flowering by IAA. Our results have shown that the inhibitory effect of IAA on Pharbitis nil flowering is not physiological but is connected with its effect on ethylene biosynthesis. 相似文献
3.
The influence of jasmonic acid (JA) on differentiation of meristems of the potato,Solanum tuberosum cv. Vesna, was investigated in vitro. Meristems were grown on Murashige and Skoog (MS) medium supplemented with indole-3-acetic acid (IAA) (10 μM), kinetin (10 μM), gibberellic acid (3 μM), as modified by Bang. Addition of JA in concentrations of 0.5–10 μM increased the number of meristems that developed into buds, particularly in meristems isolated from shoots grown from tubers in the dark. JA had no noticeable effect on meristems from germs grown in light. All added concentrations of JA retarded callus and root formation. The inhibitory effect on rhizogenesis disappeared immediately after transfer of the developed buds to medium without JA. 相似文献
4.
Sandra Youngman Mansoor Sarfarazi Maja Bucan Marcy MacDonald Barbara Smith Michael Zimmer Conrad Gilliam Anna-Maria Frischauf John J. Wasmuth James F. Gusella Hans Lehrach Peter S. Harper Duncan J. Shaw 《Genomics》1989,5(4)
Genetic linkage studies have mapped Huntington's disease (HD) to the distal portion of the short arm of chromosome 4 (4p16.3), 4 cM distal to D4S10 (G8). To date, no definite flanking marker has been identified. A new DNA marker, D4S90 (D5), which maps to the distal region of 4p16.3, is described. The marker was used in a genetic linkage study in the CEPH reference families with seven other markers at 4p16. The study, together with knowledge of the physical map of the region, places D4S90 as the most distal marker, 6 cM from D4S10. A provisional linkage study with HD gave a maximum lod score of 2.14 at a θ of 0.00 and no evidence of linkage disequilibrium. As D4S90 appears to be located terminally, it should play an important role in the accurate mapping and cloning of the HD gene. 相似文献
5.
Experimental alloxan- or streptozotocin-produced diabetes in rats was accompanied by an increase in the levels of norepinephrine, dopamine, and serotonin, whereas the contents of metabolites, i.e., 5-hydroxyindoleacetic acid and homovanillic acid, in the whole brain gradually decreased with the duration of diabetes. Among the striatum, thalamus, and hypothalamus of alloxan diabetic rats, monoamine alterations were observed only in the hypothalamus; after 1 week an increase of norepinephrine content and after 13 weeks an increase of norepinephrine and dopamine contents were found. Tissues of 11 brain regions of 10 diabetic and 12 control patients post mortem were investigated for monoamine concentrations. Patients were all male, of similar age and interval between death and autopsy. Diabetic patients had an increase in the content of serotonin in the medial and lateral hypothalamus. The content of dopamine increased in the medial hypothalamus, putamen, and medial and lateral pallidus. In diabetic patients, the content of norepinephrine increased in the lateral pallidus and decreased in the nucleus accumbens and claustrum. Thus, it seems that diabetes mellitus in rats, as well as in humans is associated with regionally specific changes in brain monoamines. 相似文献
6.
Maja Wiprächtiger Melanie Haupt Andreas Froemelt Magdalena Klotz Claudio Beretta Dominik Osterwalder Vanessa Burg Stefanie Hellweg 《Journal of Industrial Ecology》2023,27(1):254-271
Industrial ecology (IE) methodologies, such as input/output or material flow analysis and life cycle assessment (LCA), are often used for the environmental evaluation of circular economy strategies. Up to now, an approach that utilizes these methods in a systematic, integrated framework for a holistic assessment of a geographic region's sustainable circular economy potential has been lacking. The approach developed in this study (IE4CE approach) combines IE methodologies to determine the environmental impact mitigation potential of circular economy strategies for a defined geographic region. The approach foresees five steps. First, input/output analysis helps identify sectors with high environmental impacts. Second, a refined analysis is conducted using material flow and LCA. In step 3, circular strategies are used for scenario design and evaluated in step 4. In step 5, the assessment results are compiled and compared across sectors. The approach was applied to a case study of Switzerland, analyzing 8 sectors and more than 30 scenarios in depth. Carbon capture and storage (CCS) from waste incineration, biogas and cement production, food waste prevention in households, hospitality and production, and the increased recycling of plastics had the highest mitigation potential. Most of the scenarios do not influence each other. One exception is the CCS scenarios: waste avoidance scenarios decrease the reduction potential of CCS. A combination of scenarios from different sectors, including their impact on the CCS scenario potential, led to an environmental impact mitigation potential of 11.9 Mt CO2-eq for 2050, which equals 14% of Switzerland's current consumption-based impacts. 相似文献
7.
Michael Vreones Maja Mustapic Ruin Moaddel Krishna A. Pucha Jacqueline Lovett Douglas R. Seals Dimitrios Kapogiannis Christopher R. Martens 《Aging cell》2023,22(1):e13754
Declining nicotinamide adenine dinucleotide (NAD+) concentration in the brain during aging contributes to metabolic and cellular dysfunction and is implicated in the pathogenesis of aging-associated neurological disorders. Experimental therapies aimed at boosting brain NAD+ levels normalize several neurodegenerative phenotypes in animal models, motivating their clinical translation. Dietary intake of NAD+ precursors, such as nicotinamide riboside (NR), is a safe and effective avenue for augmenting NAD+ levels in peripheral tissues in humans, yet evidence supporting their ability to raise NAD+ levels in the brain or engage neurodegenerative disease pathways is lacking. Here, we studied biomarkers in plasma extracellular vesicles enriched for neuronal origin (NEVs) from 22 healthy older adults who participated in a randomized, placebo-controlled crossover trial (NCT02921659) of oral NR supplementation (500 mg, 2x /day, 6 weeks). We demonstrate that oral NR supplementation increases NAD+ levels in NEVs and decreases NEV levels of Aβ42, pJNK, and pERK1/2 (kinases involved in insulin resistance and neuroinflammatory pathways). In addition, changes in NAD(H) correlated with changes in canonical insulin–Akt signaling proteins and changes in pERK1/2 and pJNK. These findings support the ability of orally administered NR to augment neuronal NAD+ levels and modify biomarkers related to neurodegenerative pathology in humans. Furthermore, NEVs offer a new blood-based window into monitoring the physiologic response of NR in the brain. 相似文献
8.
Jü rg Mü ller Maja Oertle 《The Journal of steroid biochemistry and molecular biology》1993,47(1-6):213-221
In the rat adrenal cortex, two isozymes of cytochrome P-45011β (CYP11B1 and CYP11B2) have been identified. They are encoded by two different genes with a homology much higher in their coding than in their 5′-flanking regions. CYP11B1 is found in all the zones of the gland and catalyzes a single hydroxylation of deoxycorticosterone (DOC) in the 11β- or the 18-position. CYP11B2 is produced exclusively in the zona glomerulosa and catalyzes all three reactions involved in the conversion of DOC to aldosterone. In vivo and in vitro, the expression of the genes encoding CYP11B1 and CYP11B2 is regulated by two separate control systems which appear to operate both independently and interdependently. In vivo, zona glomerulosa expression of CYP11B1 was enhanced by ACTH treatment or potassium depletion and was lowered by potassium repletion. CYP11B2 expression disappeared upon potassium depletion or ACTH treatment, but reappeared during potassium repletion. In vitro, only CYP11B1 activity was detectable and responsive to ACTH treatment in zona glomerulosa cells cultured at a potassium concentration of 6.4 mmol/1. Aldosterone biosynthetic activity and mRNA encoding CYP11B2 could be detected only after at least 1 day of exposure to a high extracellular potassium concentration ( 12 mmol/1). 相似文献
9.
We have previously characterized nuclear cDNA clones encoding two RNA binding proteins, CP-RBP30 and CP-RBP-31, which are targeted to chloroplasts in Nicotiana plumbaginifolia. In this report we describe the analysis of the 3-untranslated regions (3-UTRs) in 22 CP-RBP30 and 8 CP-RBP31 clones which reveals that mRNAs encoding both proteins have a very complex polyadenylation pattern. Fourteen distinct poly(A) sites were identified among CP-RBP30 clones and four sites among the CP-RBP31 clones. The authenticity of the sites was confirmed by RNase A/T1 mapping of N. plumbaginifolia RNA. CP-RBP30 provides an extreme example of the heterogeneity known to be a feature of mRNA polyadenylation in higher plants. Using PCR we have demonstrated that CP-RBP genes in N. plumbaginifolia and N. sylvestris, in addition to the previously described introns interrupting the coding region, contain an intron located in the 3 non-coding part of the gene. In the case of the CP-RBP31, we have identified one polyadenylation event ocurring in this intron. 相似文献
10.
Paul I. Ward Cameron P. Goater Maja Mikos 《Biological journal of the Linnean Society. Linnean Society of London》1997,61(1):139-149
Snails of the genus Lymnaea are morphologically variable and their taxonomy is unclear. In particular, the forms peregra and ovata , distinguished by shell shape, are often considered variants of the same species, L. peregra. We studied a rare situation in a Swiss mountain lake where both forms are sympatric. First, we found that the forms shows complete separation for a number of allozymes. Second, we examined the response of the two snail forms to infection by the trematode Diplostomum phoxini . For the ovata form, there was a transitory, 10% increase in the growth of infected snails compared to uninfected controls. The peregra form showed no gigantism and had higher parasite-induced mortality. Third, we assessed differences between the forms in reproduction under different environmental conditions. Density negatively influenced egg production to the same degree in both forms. However, decreasing water levels, characteristic of part of the lake studied, led to a 30% decrease in egg production for the ovata form, but only a 10% decrease for the peregra form. These differences are discussed in relation to the microdistributions of the snails in the lake and we conclude that the two forms are almost certainly separate species. 相似文献