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981.
Dorota Łażewska Szczepan Mogilski Stefanie Hagenow Kamil Kuder Monika Głuch-Lutwin Agata Siwek Małgorzata Więcek Maria Kaleta Ulla Seibel Armin Buschauer Barbara Filipek Holger Stark Katarzyna Kieć-Kononowicz 《Bioorganic & medicinal chemistry》2019,27(7):1254-1262
This study focuses on the design, synthesis, molecular modeling and biological evaluation of a novel group of alkyl-1,3,5-triazinyl-methylpiperazines. New compounds were synthesized and their affinities for human histamine H4 receptor (hH4R) were evaluated. Among them, 4-(cyclohexylmethyl)-6-(4-methylpiperazin-1-yl)-1,3,5-triazin-2-amine (14) exhibited hH4R affinity with a Ki of 160?nM and behaved as antagonist in functional assays: the cellular aequorin-based assay (IC50?=?32?nM) and [35S]GTPγS binding assay (pKb?=?6.67). In addition, antinociceptive activity of 14 in vivo was observed in Formalin test (in mice) and in Carrageenan-induced acute inflammation test (in rats). 相似文献
982.
Armin Scheben Brent Verpaalen Cynthia T. Lawley Chon‐Kit K. Chan Philipp E. Bayer Jacqueline Batley David Edwards 《The Plant journal : for cell and molecular biology》2019,98(1):142-152
Advances in sequencing technology have led to a rapid rise in the genomic data available for plants, driving new insights into the evolution, domestication and improvement of crops. Single nucleotide polymorphisms (SNPs) are a major component of crop genomic diversity, and are invaluable as genetic markers in research and breeding programs. High‐throughput SNP arrays, or ‘SNP chips’, can generate reproducible sets of informative SNP markers and have been broadly adopted. Although there are many public repositories for sequencing data, which are routinely uploaded, there are no formal repositories for crop SNP array data. To make SNP array data more easily accessible, we have developed CropSNPdb ( http://snpdb.appliedbioinformatics.com.au ), a database for SNP array data produced by the Illumina Infinium? hexaploid bread wheat (Triticum aestivum) 90K and Brassica 60K arrays. We currently host SNPs from datasets covering 526 Brassica lines and 309 bread wheat lines, and provide search, download and upload utilities for users. CropSNPdb provides a useful repository for these data, which can be applied for a range of genomics and molecular crop‐breeding activities. 相似文献
983.
Ramezannezhad Rezvan Bojnoordi Morteza Mofid Armin Mohammad Aghdasi Mahnaz 《In vitro cellular & developmental biology. Plant》2022,58(4):653-663
In Vitro Cellular & Developmental Biology - Plant - The present study aims to model and optimize phenolic acid production from Lactuca undulate Ledeb. root- and leaf-derived callus using the... 相似文献
984.
985.
A critical factor in the biotechnological production of l-lysine with Corynebacterium glutamicum is the sufficient supply of NADPH. The membrane-integral nicotinamide nucleotide transhydrogenase PntAB of Escherichia coli can use the electrochemical proton gradient across the cytoplasmic membrane to drive the reduction of NADP+ via the oxidation of NADH. As C. glutamicum does not possess such an enzyme, we expressed the E. coli pntAB genes in the genetically defined C. glutamicum lysine-producing strain DM1730, resulting in membrane-associated transhydrogenase activity of 0.7 U/mg protein. When cultivated
in minimal medium with 10% (w/v) carbon source, the presence of transhydrogenase slightly reduced glucose consumption, whereas the consumption of fructose,
glucose plus fructose, and, in particular, sucrose was stimulated. Biomass was increased by pntAB expression between 10 and 30% on all carbon sources tested. Most importantly, the lysine concentration was increased in the
presence of transhydrogenase by ∼10% on glucose, ∼70% on fructose, ∼50% on glucose plus fructose, and even by ∼300% on sucrose.
Thus, the presence of a proton-coupled transhydrogenase was shown to be an efficient way to improve lysine production by C. glutamicum. In contrast, pntAB expression had a negative effect on growth and glutamate production of C. glutamicum wild type. 相似文献
986.
Just A 《American journal of physiology. Regulatory, integrative and comparative physiology》2007,292(1):R1-17
Autoregulation of renal blood flow (RBF) is caused by the myogenic response (MR), tubuloglomerular feedback (TGF), and a third regulatory mechanism that is independent of TGF but slower than MR. The underlying cause of the third regulatory mechanism remains unclear; possibilities include ATP, ANG II, or a slow component of MR. Other mechanisms, which, however, exert their action through modulation of MR and TGF are pressure-dependent change of proximal tubular reabsorption, resetting of RBF and TGF, as well as modulating influences of ANG II and nitric oxide (NO). MR requires < 10 s for completion in the kidney and normally follows first-order kinetics without rate-sensitive components. TGF takes 30-60 s and shows spontaneous oscillations at 0.025-0.033 Hz. The third regulatory component requires 30-60 s; changes in proximal tubular reabsorption develop over 5 min and more slowly for up to 30 min, while RBF and TGF resetting stretch out over 20-60 min. Due to these kinetic differences, the relative contribution of the autoregulatory mechanisms determines the amount and spectrum of pressure fluctuations reaching glomerular and postglomerular capillaries and thereby potentially impinge on filtration, reabsorption, medullary perfusion, and hypertensive renal damage. Under resting conditions, MR contributes approximately 50% to overall RBF autoregulation, TGF 35-50%, and the third mechanism < 15%. NO attenuates the strength, speed, and contribution of MR, whereas ANG II does not modify the balance of the autoregulatory mechanisms. 相似文献
987.
Just A Olson AJ Whitten CL Arendshorst WJ 《American journal of physiology. Heart and circulatory physiology》2007,292(1):H83-H92
NAD(P)H oxidases (NOX) and reactive oxygen species (ROS) are involved in vasoconstriction and vascular remodeling during hypertension produced by chronic angiotensin II (ANG II) infusion. These effects are thought to be mediated largely through superoxide anion (O(2)(-)) scavenging of nitric oxide (NO). Little is known about the role of ROS in acute vasoconstrictor responses to agonists. We investigated renal blood flow (RBF) reactivity to ANG II (4 ng), norepinephrine (NE, 20 ng), and alpha(1)-adrenergic agonist phenylephrine (PE, 200 ng) injected into the renal artery (ira) of anesthetized Sprague-Dawley rats. The NOX inhibitor apocynin (1-4 mg.kg(-1).min(-1) ira, 2 min) or the superoxide dismutase mimetic Tempol (1.5-5 mg.kg(-1).min(-1) ira, 2 min) rapidly increased resting RBF by 8 +/- 1% (P < 0.001) or 3 +/- 1% (P < 0.05), respectively. During NO synthase (NOS) inhibition (N(omega)-nitro-l-arginine methyl ester, 25 mg/kg iv), the vasodilation tended to increase (apocynin 13 +/- 4%, Tempol 10 +/- 1%). During control conditions, both ANG II and NE reduced RBF by 24 +/- 4%. Apocynin dose dependently reduced the constriction by up to 44% (P < 0.05). Similarly, Tempol blocked the acute actions of ANG II and NE by up to 48-49% (P < 0.05). In other animals, apocynin (4 mg.kg(-1).min(-1) ira) attenuated vasoconstriction to ANG II, NE, and PE by 46-62% (P < 0.01). During NOS inhibition, apocynin reduced the reactivity to ANG II and NE by 60-72% (P < 0.01), and Tempol reduced it by 58-66% (P < 0.001). We conclude that NOX-derived ROS substantially contribute to basal RBF as well as to signaling of acute renal vasoconstrictor responses to ANG II, NE, and PE in normal rats. These effects are due to O(2)(-) rather than H(2)O(2), occur rapidly, and are independent of scavenging of NO. 相似文献
988.
Pflüger K Ehrenreich A Salmon K Gunsalus RP Deppenmeier U Gottschalk G Müller V 《FEMS microbiology letters》2007,277(1):79-89
Methanosarcina mazei is a nonhalophilic methanogen that can adapt to 800 mM NaCl. Microarray studies have been used to examine the effect of elevated salinities on the regulation of gene expression in M. mazei. Eighty-four genes of different functional categories, such as solute transport and biosynthesis, Na(+) export, stress response, ion, protein and phosphate transport, metabolic enzymes, regulatory proteins, DNA-modification systems, and cell-surface modulators, were found to be stronger expressed at high salinities. Moreover, 10 genes encoding different metabolic functions including potassium uptake and ATP synthesis were reduced in expression under high salt. The overall expression profiles suggest that M. mazei is able to adapt to high salinities by multiple upregulation of many different cellular functions including protective pathways such as solute transport and biosynthesis, import of phosphate, export of Na(+), and upregulation of pathways for modification of DNA and cell surface architecture. 相似文献
989.
The transcription factor Yin Yang 1 is essential for oligodendrocyte progenitor differentiation 总被引:8,自引:0,他引:8
He Y Dupree J Wang J Sandoval J Li J Liu H Shi Y Nave KA Casaccia-Bonnefil P 《Neuron》2007,55(2):217-230
990.
Distribution of lactate dehydrogenase in healthy and degenerative canine stifle joint cartilage 总被引:1,自引:1,他引:0
Walter EL Spreng D Schmöckel H Schawalder P Tschudi P Friess AE Stoffel MH 《Histochemistry and cell biology》2007,128(1):7-18
In dogs, degenerative joint diseases (DJD) have been shown to be associated with increased lactate dehydrogenase (LDH) activity
in the synovial fluid. The goal of this study was to examine healthy and degenerative stifle joints in order to clarify the
origin of LDH in synovial fluid. In order to assess the distribution of LDH, cartilage samples from healthy and degenerative
knee joints were investigated by means of light and transmission electron microscopy in conjunction with immunolabeling and
enzyme cytochemistry. Morphological analysis confirmed DJD. All techniques used corroborated the presence of LDH in chondrocytes
and in the interterritorial matrix of healthy and degenerative stifle joints. Although enzymatic activity of LDH was clearly
demonstrated in the territorial matrix by means of the tetrazolium–formazan reaction, immunolabeling for LDH was missing in
this region. With respect to the distribution of LDH in the interterritorial matrix, a striking decrease from superficial
to deeper layers was present in healthy dogs but was missing in affected joints. These results support the contention that
LDH in synovial fluid of degenerative joints originates from cartilage. Therefore, we suggest that (1) LDH is transferred
from chondrocytes to ECM in both healthy dogs and dogs with degenerative joint disease and that (2) in degenerative joints,
LDH is released from chondrocytes and the ECM into synovial fluid through abrasion of cartilage as well as through enhanced
diffusion as a result of increased water content and degradation of collagen. 相似文献