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111.
Natalia Fedtsova Elena A. Komarova Kellee F. Greene Liliya R. Novototskaya Ivan Molodtsov Craig M. Brackett Evguenia Strom Anatoli S. Gleiberman Alexander N. Shakhov Andrei V. Gudkov 《Cell death & disease》2021,12(6)
Transplantation of bone marrow (BM) is made possible by the differential sensitivity of its stromal and hematopoietic components to preconditioning by radiation and/or chemotherapeutic drugs. These genotoxic treatments eliminate host hematopoietic precursors by inducing p53-mediated apoptosis but keep the stromal niche sufficiently intact for the engraftment of donor hematopoietic cells. We found that p53-null mice cannot be rescued by BM transplantation (BMT) from even the lowest lethal dose of total body irradiation (TBI). We compared structural changes in BM stroma of mice differing in their p53 status to understand why donor BM failed to engraft in the irradiated p53-null mice. Irradiation did not affect the general structural integrity of BM stroma and induced massive expression of alpha-smooth muscle actin in mesenchymal cells followed by increased adiposity in p53 wild-type mice. In contrast, none of these events were found in p53-null mice, whose BM stroma underwent global structural damage following TBI. Similar differences in response to radiation were observed in in vitro-grown bone-adherent mesenchymal cells (BAMC): p53-null cells underwent mitotic catastrophe while p53 wild-type cells stayed arrested but viable. Supplementation with intact BAMC of either genotype enabled donor BM engraftment and significantly extended longevity of irradiated p53-null mice. Thus, successful preconditioning depends on the p53-mediated protection of cells critical for the functionality of BM stroma. Overall, this study reveals a dual positive role of p53 in BMT: it drives apoptotic death of hematopoietic cells and protects BM stromal cells essential for its functionality.Subject terms: Haematopoietic stem cells, Stem-cell research 相似文献
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Irina Chernukha Liliya Fedulova Ekaterina Vasilevskaya Andrei Kulikovskii Nadezhda Kupaeva Elena Kotenkova 《Saudi Journal of Biological Sciences》2021,28(5):2877-2885
The role of natural antioxidants in preventing of age-relating diseases is evident. The vegetable industry generates a large amount of waste, which is a good source of antioxidants.The aim of the study was the investigation of the antioxidant effect of long-term consumption of ethanolic yellow onion husk extract in ageing laboratory rodents.Twenty male Wistar albino rats were divided randomly into two groups (n = 10): a control group and an experimental group that received ethanolic yellow onion husk extract (2 mL/rat diluted with distilled water; activity of 4.44 µmol-equiv. quercetin) for 188 days. Oxygen radical absorbance capacity and ferric reducing antioxidant power assays were used to determine the total antioxidant capacity of the extract, which amounted to 941.4 ± 32.7 µmol equiv. Trolox/g raw material and 167.4 ± 16.4 µmol-equiv. quercetin/g raw material, respectively. Oral intake of the onion husk extract affected the indicators of the antioxidant system of the liver and the brain but not of the blood and plasma, mainly due to elevations in the activity of catalase and superoxide dismutase in the liver by 44.4% and 79.1%, respectively, and in the brain by three-fold and 79.1%, respectively.The availability, cheapness and high antioxidant potential of onion waste qualifies it a good source of functional ingredients and bioactive substances applicable in the food and pharmaceutical industries. 相似文献
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Quadruplex DNAs can fold into a variety of distinct topologies, depending in part on loop types and orientations of individual strands, as shown by high-resolution crystal and NMR structures. Crystal structures also show associated water molecules. We report here on an analysis of the hydration arrangements around selected folded quadruplex DNAs, which has revealed several prominent features that re-occur in related structures. Many of the primary-sphere water molecules are found in the grooves and loop regions of these structures. At least one groove in anti-parallel and hybrid quadruplex structures is long and narrow and contains an extensive spine of linked primary-sphere water molecules. This spine is analogous to but fundamentally distinct from the well-characterized spine observed in the minor groove of A/T-rich duplex DNA, in that every water molecule in the continuous quadruplex spines makes a direct hydrogen bond contact with groove atoms, principally phosphate oxygen atoms lining groove walls and guanine base nitrogen atoms on the groove floor. By contrast, parallel quadruplexes do not have extended grooves, but primary-sphere water molecules still cluster in them and are especially associated with the loops, helping to stabilize loop conformations. 相似文献
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Elliott C.R. Hall Evgeny A. Lysenko Ekaterina A. Semenova Oleg V. Borisov Oleg N. Andryushchenko Liliya B. Andryushchenko Tatiana F. Vepkhvadze Egor M. Lednev Piotr Zmijewski Daniil V. Popov Edward V. Generozov Ildus I. Ahmetov 《Biology of sport / Institute of Sport》2021,38(2):277
Direct determination of muscle fiber composition is invasive and expensive, with indirect methods also requiring specialist resources and expertise. Performing resistance exercises at 80% 1RM is suggested as a means of indirectly estimating muscle fiber composition, though this hypothesis has never been validated against a direct method. The aim of the study was to investigate the relationship between the number of completed repetitions at 80% 1RM of back squat exercise and muscle fiber composition. Thirty recreationally active participants’ (10 females, 20 males) 1RM back squat load was determined, before the number of consecutive repetitions at 80% 1RM was recorded. The relationship between the number of repetitions and the percentage of fast-twitch fibers from vastus lateralis was investigated. The number of completed repetitions ranged from 5 to 15 and was independent of sex, age, 1RM, training frequency, training type, training experience, BMI or muscle fiber cross-sectional area. The percentage of fast-twitch muscle fibers was inversely correlated with the number of repetitions completed (r = –0.38, P = 0.039). Participants achieving 5 to 8 repetitions (n = 10) had significantly more fast-twitch muscle fibers (57.5 ± 9.5 vs 44.4 ± 11.9%, P = 0.013) than those achieving 11–15 repetitions (n = 11). The remaining participants achieved 9 or 10 repetitions (n = 9) and on average had equal proportion of fast- and slow-twitch muscle fibers. In conclusion, the number of completed repetitions at 80% of 1RM is moderately correlated with muscle fiber composition. 相似文献
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Andrey V. Smolobochkin Ekaterina A. Muravyeva Liliya I. Vagapova Irina R. Knyazeva Julia K. Voronina Alexander R. Burilov Michail A. Pudovik Anastasiya V. Gildebrant Ivan S. Sazykin Marina A. Sazykina Almir S. Gazizov 《化学与生物多样性》2019,16(1)
The approach to the novel 1‐[(2‐aminoethyl)sulfonyl]‐2‐arylpyrrolidines via unique intramolecular cyclization/aza‐Michael reactions of N‐(4,4‐diethoxybutyl)ethenesulfonamide have been developed, which benefits from high yields of target compounds, mild reaction conditions, usage of inexpensive and low‐toxic reagents, and allows for wide variability in both amine and aryl moieties. Biotesting with whole‐cell luminescent bacterial biosensors responding to DNA damage showed that all tested compounds are not genotoxic. Tested compounds differently affect the formation of biofilms by Vibrio aquamarinus DSM 26054. Some of the tested compounds were found to suppress the bacterial biofilms growth and thus are promising candidates for further studies. 相似文献