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71.
Obtaining oat DH lines is only effective via wide crossing with maize. Seven hundred haploid embryos from 21 single F1 progeny obtained from wide crosses with maize were isolated, divided into four groups according to their size (<0.5 mm, 0.5–0.9 mm, 1.0–1.4 mm, and ≥1.5 mm), and transferred into 190–2 regeneration medium with different growth regulators: 0.5 mg L?1 kinetin (KIN) and 0.5 mg L?1 1-naphthaleneacetic acid (NAA); 1 mg L?1 zeatin (ZEA) and 0.5 mg L?1 NAA; or 1 mg L?1 dicamba (DIC), 1 mg L?1 picloram (PIC), and 0.5 mg L?1 kinetin (KIN). Among all isolated embryos, approximately 46.1% were between 1.0–1.4 mm, while the smallest group of embryos (7.1%) were those <0.5 mm. The ability of haploid embryos to germinate varied depending on oat genotypes and the size of embryos. Haploid embryos <0.5 mm were globular and did not germinate, whereas embryos ≥1.5 mm had clearly visible coleoptiles, radicles, and scutella, and were able to germinate. Germination of oat haploid embryos varied depending on growth regulators in the regeneration medium. Most haploid embryos germinated on medium with 0.5 mg L?1 NAA and 0.5 mg L?1 KIN, while the fewest germinated on medium with 1 mg L?1 DIC, 1 mg L?1 PIC, and 0.5 mg L?1 KIN. One hundred thirty germinated haploid embryos converted into haploid plants. Fifty oat DH lines were obtained after colchicine treatment.  相似文献   
72.
Obesity and endocrine disorders have become prevalent issues in the field of both human and veterinary medicine. Equine metabolic syndrome is a complex disorder involving alternation in metabolism and chronic systemic inflammation. It has been shown that unfavourable microenvironment of inflamed adipose tissue negatively affects adipose stem cell population (ASC) residing within, markedly limiting their therapeutic potential. ASCsEMS are characterized by increased senescence apoptosis, excessive accumulation of reactive oxygen species (ROS), mitochondria deterioration and “autophagic flux.” The aim of the present study was to evaluate whether treatment of ASCsEMS with a combination of 5‐azacytydine (AZA) and resveratrol (RES) would reverse aged phenotype of these cells. For this reason, we performed the following analyzes: molecular biology (RT‐PCR), microscopic (immunofluorescence, TEM) and flow cytometry (JC‐1, ROS, Ki67). We evaluated the mitochondrial status, dynamics and clearance as well as autophagic pathways. Furthermore, we investigated epigenetic alternations in treated cells by measuring the expression of TET genes and analysis of DNA methylation status. We have demonstrated that AZA/RES treatment of ASCsEMS is able to rejuvenate these cells by modulating mitochondrial dynamics, in particular by promoting mitochondrial fusion over fission. After AZA/RES treatment, ASCsEMS were characterized by increased proliferation rate, decreased apoptosis and senescence and lower ROS accumulation. Our findings offer a novel approach and potential targets for the beneficial effects of AZA/RES in ameliorating stem cell dysfunctions.  相似文献   
73.
International Journal of Peptide Research and Therapeutics - Relations between structural modifiactions and SOD-like activity of four branched CuII-metallopeptides based on l-2,3-diaminopropionic...  相似文献   
74.
Late‐onset retinal degeneration (L‐ORD) is an autosomal dominant macular degeneration characterized by the formation of sub‐retinal pigment epithelium (RPE) deposits and neuroretinal atrophy. L‐ORD results from mutations in the C1q‐tumor necrosis factor‐5 protein (CTRP5), encoded by the CTRP5/C1QTNF5 gene. To understand the mechanism underlying L‐ORD pathology, we used a human cDNA library yeast two‐hybrid screen to identify interacting partners of CTRP5. Additionally, we analyzed the Bruch's membrane/choroid (BM‐Ch) from wild‐type (Wt), heterozygous S163R Ctrp5 mutation knock‐in (Ctrp5S163R/wt), and homozygous knock‐in (Ctrp5S163R/S163R) mice using mass spectrometry. Both approaches showed an association between CTRP5 and HTRA1 via its C‐terminal PDZ‐binding motif, stimulation of the HTRA1 protease activity by CTRP5, and CTRP5 serving as an HTRA1 substrate. The S163R‐CTRP5 protein also binds to HTRA1 but is resistant to HTRA1‐mediated cleavage. Immunohistochemistry and proteomic analysis showed significant accumulation of CTRP5 and HTRA1 in BM‐Ch of Ctrp5S163R/S163R and Ctrp5S163R/wt mice compared with Wt. Additional extracellular matrix (ECM) components that are HTRA1 substrates also accumulated in these mice. These results implicate HTRA1 and its interaction with CTRP5 in L‐ORD pathology.  相似文献   
75.
Journal of Physiology and Biochemistry - AMP-activated protein kinase (AMPK) is present in different kinds of metabolically active cells. AMPK is an important intracellular energy sensor and plays...  相似文献   
76.
Searching for CNS active cyclic amines derivatives containing heterocyclic xanthone core we designed and synthesized a set of fourteen novel 2- or 4-methylxanthone substituted by alkyl- or aryl-piperazine moieties. The compounds were evaluated in vivo for their potential antidepressant-like activity (in the forced swim test) and anxiolytic-like activity (four-plate test) and their inhibitory effect against rat 5-HT2 receptor was checked. The pharmacokinetic analysis of active compounds done by a non-compartmental approach have shown a rapid absorption of all studied molecules from intraperitoneal cavity and good penetration the blood-brain barrier after i.p. administration with brain to plasma ratios varied from 2.8 to 31.6. Genotoxicity and biotransformation of active compounds were studied. Compound 19 interactions with major classes of GPCRs, uptake systems and ion channels were tested and results indicated that it binds to 5-HT2A, 5-HT2B receptors and sodium channels.  相似文献   
77.
Targeted covalent inhibitors of urease were developed on the basis of the catechol structure. Forty amide and ester derivatives of 3,4-dihydroxyphenylacetic acid, caffeic acid, ferulic acid and gallic acid were obtained and screened against Sporosarcinia pasteurii urease. The most active compound, namely propargyl ester of 3,4-dihydroxyphenylacetic acid exhibited IC50?=?518?nM andkinact/Ki?=?1379?M?1?s?1. Inhibitory activity of this compound was better and toxicity lower than those obtained for the starting compound – catechol. The molecular modelling studies revealed a mode of binding consistent with structure-activity relationships.  相似文献   
78.
79.
Forest undergrowth plants are tightly connected with the shady and humid conditions that occur under the canopy of tropical forests. However, projected climatic changes, such as decreasing precipitation and increasing temperature, negatively affect understory environments by promoting light‐demanding and drought‐tolerant species. Therefore, we aimed to quantify the influence of climate change on the spatial distribution of three selected forest undergrowth plants, Dracaena Vand. ex L. species, D. afromontana Mildbr., D. camerooniana Baker, and D. surculosa Lindl., simultaneously creating the most comprehensive location database for these species to date. A total of 1,223 herbarium records originating from tropical Africa and derived from 93 herbarium collections worldwide have been gathered, validated, and entered into a database. Species‐specific Maxent species distribution models (SDMs) based on 11 bioclimatic variables from the WorldClim database were developed for the species. HadGEM2‐ES projections of bioclimatic variables in two contrasting representative concentration pathways (RCPs), RCP2.6 and RCP8.5, were used to quantify the changes in future potential species distribution. D. afromontana is mostly sensitive to temperature in the wettest month, and its potential geographical range is predicted to decrease (up to ?63.7% at RCP8.5). Optimum conditions for D. camerooniana are low diurnal temperature range (6–8°C) and precipitation in the wettest season exceeding 750 mm. The extent of this species will also decrease, but not as drastically as that of D. afromontana. D. surculosa prefers high precipitation in the coldest months. Its potential habitat area is predicted to increase in the future and to expand toward the east. This study developed SDMs and estimated current and future (year 2050) potential distributions of the forest undergrowth Dracaena species. D. afromontana, naturally associated with mountainous plant communities, was the most sensitive to predicted climate warming. In contrast, D. surculosa was predicted to extend its geographical range, regardless of the climate change scenario.  相似文献   
80.
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