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21.
High Quality Independent From a Donor: Human Amniotic Fluid Derived Stem Cells—A Practical Analysis Based on 165 Clinical Cases 下载免费PDF全文
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Terpenes are a widespread group of secondary metabolites that can be found in various family plants such as the Lamiaceae. In view of their numerous valuable biological activities, the industrial production of concrete terpenes and essential oils rich in the substances is intensively studied. Monoterpenes constitute a significant part of the whole group of the aforementioned secondary metabolites. This is due to their numerous biological activities and their ability to permeate the skin. Despite the fact that these substances have gain popularity, they are not comprehensively characterized. The presented review is based on studies of the biological activities of the most important monoterpenes and the essential oils rich in these compounds. The authors focused attention on antioxidant activity, inhibition towards acetyl‐ and butyrylcholinesterase, and α‐amylase and α‐glucosidase, antifungal, hepatoprotective, sedative properties, and their skin permeation enhancement. 相似文献
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Elzbieta Sucajtys-Szulc Alicja Debska-Slizien Boleslaw Rutkowski Ryszard Milczarek Iwona Pelikant-Malecka Tomasz Sledzinski Julian Swierczynski Marek Szolkiewicz 《Molecular and cellular biochemistry》2018,439(1-2):11-18
Little is known about the effects of coffee that are not related to the presence of caffeine. The aim of the study was to analyse changes in kidney function and nucleotide metabolism related to high intake of decaffeinated coffee. Mice consumed decaffeinated coffee extract for two weeks. Activities of AMP deaminase, ecto5′-nucleotidase, adenosine deaminase, purine nucleoside phosphorylase were measured in kidney cortex and medulla by analysis of conversion of substrates into products using HPLC. Concentration of nucleotides in kidney cortex, kidney medulla and serum were estimated by HPLC. Activity of ecto5′-nucleotidase increased from 0.032 ± 0.006 to 0.049 ± 0.014 nmol/mg tissue/min in kidney cortex of mice administered high-dose decaffeinated coffee (HDC) together with increase in cortex adenosine concentration and decrease in plasma creatinine concentration. HDC leads to increased activity of ecto5′-nucleotidase in kidney cortex that translates to increase in concentration of adenosine. Surprisingly this caused improved kidney excretion function. 相似文献
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Choline-containing teichoic acid seems to be essential for the adsorption of bacteriophage Dp-1 to pneumococci. This conclusion is based on the following observations: In contrast to pneumococci grown in choline-containing medium, cells grown in medium containing ethanolamine or other submethylated aminoalcohols instead of choline were found to be resistant to infection by Dp-1. Live choline-grown bacteria and heat- or UV-inactivated cells and purified cell walls prepared from these cells were capable of adsorbing phage Dp-1; ethanolamine-grown pneumococci or cell wall preparations were unable to do so. Adsorption of Dp-1 to choline-containing cell walls was competitively inhibited by phosphorylcholine and by several choline-containing soluble cell surface components, such as the Forssman antigen and the teichoic acid-glycan complexes formed by autolytic cell wall degradation. Cell walls prepared from pneumococci grown in ethanolamine or phosphorylethanolamine were inactive. Electron microscopic studies with pneumococci that had segments of choline-containing cell wall material amid ethanolamine-containing regions indicated that the Dp-1 phage particles adsorbed exclusively to the choline-containing surface areas. We suggest that the choline residues of the pneumococcal teichoic acid are essential components of the Dp-1 phage receptors in this bacterium. 相似文献
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Folliculogenesis was studied daily in the 18 oestrous cycles in six prolific Olkuska ewes from October to December using transrectal ultrasonography to record the number and size of all ovarian follicles > or =2 mm in diameter. Blood samples were taken once a day and were analyzed for concentrations of FSH, LH, estradiol and progesterone. Follicular and hormonal data were analyzed for associations between different stages of development of the follicular waves and concentrations of FSH and estradiol. The first wave during which at least one follicle reached maximum diameter of > or =4 mm after ovulation, was defined as a wave 1, and the following waves were numbered sequentially. Waves 1, 2, 3, 4 and the ovulatory one emerged on days: -2 to 4, 4 to 8, 6 to 11, 10 to 12 and 11 to 15, respectively. The mean number of follicles per wave that reached diameter of > or =4 mm was 4.15 +/- 1.1 and 16.62 +/- 8.6 follicles per estrous cycle of a total 299 follicles were observed. Significantly more follicles (p> or =0.05) emerged on days 2, 8 and 13 than in other days. Serum FSH concentrations fluctuated from 0.11 ngml(-1) on day 2 to preovulatory maximum 1.81 ngml(-1) on day 17 of the estrous cycle. The emergence of follicular waves was associated with elevations of FSH concentrations in blood serum. The mean increase in FSH concentration was followed by the recruitment of follicles of the next wave. The mean daily FSH concentration and the mean number of follicles emerging each day were negatively correlated. The length of the interwave interval (4.4 +/- 1.6 days) did not differ significantly from the interval between pulses of FSH (4.8 +/- 0.3 days). The mean serum estradiol concentrations showed fluctuations until day 14 and then gradually increased from 5.47 +/- 0.3 pgml(-1) to reach a peak 13.14 +/- 0.2 pgml(-1) on the day before ovulation. To summarize, the growth of ovarian follicles during the estrous cycle in high fecundity Olkuska sheep exhibited a distinct wave-like pattern. Ovarian follicles emerged from the pool of 2 mm follicles. The preovulatory follicles originated from the large follicle population were present in the ovary at the time of luteal regression. The initial stages of the growth of the largest follicles appears to be controlled primarily by increases in FSH secretion. 相似文献
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Does operational sex ratio influence relative strength of purging selection in males versus females?
Agata Plesnar‐Bielak Karolina Sychta Tomasz S. Gaczorek Joanna K. Palka Monika A. Prus Zofia M. Prokop 《Journal of evolutionary biology》2020,33(1):80-88
According to theory, sexual selection in males may efficiently purge mutation load of sexual populations, reducing or fully compensating ‘the cost of males’. For this to occur, mutations not only need to be deleterious to both sexes, they also must affect males more than females. A frequently overlooked problem is that relative strength of selection on males versus females may vary between environments, with social conditions being particularly likely to affect selection in males and females differently. Here, we induced mutations in red flour beetles (Tribolium castaneum) and tested their effect in both sexes under three different operational sex ratios (1:2, 1:1 and 2:1). Induced mutations decreased fitness of both males and females, but their effect was not stronger in males. Surprisingly, operational sex ratio did not affect selection against deleterious mutations nor its relative strength in the sexes. Thus, our results show no support for the role of sexual selection in the evolutionary maintenance of sex. 相似文献
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Paluchowska MH Bugno R Duszyńska B Tatarczyńska E Nikiforuk A Lenda T Chojnacka-Wójcik E 《Bioorganic & medicinal chemistry》2007,15(22):7116-7125
New, flexible (7, 9, 11 and 13) and rigid (8, 10, 12 and 14) imides with a 1-(m-trifluorophenyl)piperazine fragment and a tetramethylene or a 1e,4e-cyclohexylene spacer, respectively, showed very high affinity (K(i)=0.3-34 nM) and agonistic in vivo activity for 5-HT(1A) receptors. Flexible new compounds and the previously described 5 also bound to 5-HT(7) receptors (K(i)=21-134 nM). Selected glutarimide derivatives, that is, the most potent postsynaptic 5-HT(1A) receptor agonist rigid compound 8 and its flexible analogue 7, as well as the previously described full agonist-rigid compound 6 and the partial agonist-its flexible counterpart 5 exhibited moderate affinity for alpha(1)-adrenoceptors (K(i)=85 - 268 nM), but were practically devoid of any affinity for dopamine D(2) sites. Those glutarimides demonstrated anxiolytic- (5 and 7) and antidepressant-like (5, 6 and 8) activity in the four-plate and the swim tests in mice, respectively; at the same time, however, they inhibited the locomotor activity of mice. The antidepressant-like effect of 8 was significantly stronger than that induced by imipramine used as a reference antidepressant. 相似文献
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Stepkowski T Brzeziński K Legocki AB Jaskólski M Béna G 《Molecular phylogenetics and evolution》2005,34(1):15-28
S-Adenosylhomocysteine hydrolase (SahH) is involved in the degradation of the compound which inhibits methylation reactions. Using a Bayesian approach and other methods, we reconstructed a phylogenetic tree of amino acid sequences of this protein originating from all three major domains of living organisms. The SahH sequences formed two major branches: one composed mainly of Archaea and the other of eukaryotes and majority of bacteria, clearly contradicting the three-domain topology shown by small subunit rRNA gene. This topology suggests the occurrence of lateral transfer of this gene between the domains. Poor resolution of eukaryotes and bacteria excluded an ultimate conclusion in which out of the two domains this gene appeared first, however, the congruence of the secondary branches with SS rRNA and/or concatenated ribosomal protein datasets phylogenies suggested an "early" acquisition by some bacterial and eukaryotic phyla. Similarly, the branching pattern of Archaea reflected the phylogenies shown by SS rRNA and ribosomal proteins. SahH is widespread in Eucarya, albeit, due to reductive evolution, it is missing in the intracellular parasite Encephalitozoon cuniculi. On the other hand, the lack of affinity to the sequences from the alpha-Proteobacteria and cyanobacteria excludes a possibility of its acquisition in the course of mitochondrial or chloroplast endosymbioses. Unlike Archaea, most bacteria carry MTA/SAH nucleosidase, an enzyme involved also in metabolism of methylthioadenosine. However, the double function of MTA/SAH nucleosidase may be a barrier to ensure the efficient degradation of S-adenosylhomocysteine, specially when the intensity of methylation processes is high. This would explain the presence of S-adenosylhomocysteine hydrolase in the bacteria that have more complex metabolism. On the other hand, majority of obligate pathogenic bacteria due to simpler metabolism rely entirely on MTA/SAH nucleosidase. This could explain the observed phenetic pattern in which bacteria with larger (>6 Mb-million base pairs) genomes carry SAH hydrolase, whereas bacteria that have undergone reductive evolution usually carry MTA/SAH nucleosidase. This suggests that the presence or acquisition of S-adenosylhomocysteine hydrolase in bacteria may predispose towards higher metabolic, and in consequence, higher genomic complexity. The good examples are the phototrophic bacteria all of which carry this gene, however, the SahH phylogeny shows lack of congruence with SSU rRNA and photosyntethic genes, implying that the acquisition was independent and presumably preceded the acquisition of photosyntethic genes. The majority of cyanobacteria acquired this gene from Archaea, however, in some species the sahH gene was replaced by a copy from the beta- or gamma-Proteobacteria. 相似文献