共查询到20条相似文献,搜索用时 31 毫秒
1.
Aaron U. Seto Brian M. Culp Charles J. Gatt Jr. Michael Dunn 《Cell and tissue banking》2013,14(4):655-665
Successful protection of tissue properties against ionizing radiation effects could allow its use for terminal sterilization of musculoskeletal allografts. In this study we functionally evaluate Achilles tendon allografts processed with a previously developed radioprotective treatment based on (1-ethyl-3-(3-dimethylaminopropyl)carbodiimide) crosslinking and free radical scavenging using ascorbate and riboflavin, for ovine anterior cruciate ligament reconstruction. Arthroscopic anterior cruciate ligament (ACL) reconstruction was performed using double looped allografts, while comparing radioprotected irradiated and fresh frozen allografts after 12 and 24 weeks post-implantation, and to control irradiated grafts after 12 weeks. Radioprotection was successful at preserving early subfailure mechanical properties comparable to fresh frozen allografts. Twelve week graft stiffness and anterior-tibial (A-T) translation for radioprotected and fresh frozen allografts were comparable at 30 % of native stiffness, and 4.6 and 5 times native A-T translation, respectively. Fresh frozen allograft possessed the greatest 24 week peak load at 840 N and stiffness at 177 N/mm. Histological evidence suggested a delay in tendon to bone healing for radioprotected allografts, which was reflected in mechanical properties. There was no evidence that radioprotective treatment inhibited intra-articular graft healing. This specific radioprotective method cannot be recommended for ACL reconstruction allografts, and data suggest that future efforts to improve allograft sterilization procedures should focus on modifying or eliminating the pre-crosslinking procedure. 相似文献
2.
V V Znamenski? A V Terekhov T S Leonova P G Zherebchenko V G Iashunski? 《Radiobiologiia》1986,26(6):812-814
Oxolinic acid was shown to produce a radioprotective effect on mice and a therapeutic radioprotective action on rats and hamsters. As to radioprotective efficiency, oxolinic acid is inferior to such known sulfur-containing agents as indolylalkylamines and alpha-adrenomimetics. But oxolinic acid has an important advantage over them, that is, the increase in radioresistance it induces persists for several hours. The radioprotective effectiveness of oxolinic acid prompts that it is expedient to search for new radioprotective preparations among specific inhibitors of DNA polymerase of replicative synthesis. 相似文献
3.
V G Vladimirov Iu E Strel'nikov S V Amosova G M Gavrilova V I Gostevskaia A S Petrov L A Sharova 《Radiobiologiia》1990,30(1):69-75
A new group of radioprotective agents, dimethylaminodithiazines, was discovered. The agents are effective when used in relatively small amounts and exert a radioprotective effect rapidly with both intraperitoneal and per os injections. The role of inhibition of oxidative processes and DNA biosynthesis in the mechanism of radioprotective action of dimethylaminodithiazines is discussed. 相似文献
4.
V G Vladimirov O N Chupakhin A P Novikova L G Egorova N I Libikova 《Radiobiologiia》1987,27(4):528-532
The amino group is shown to be the reaction center that is primarily responsible for the radioprotective effect of the thiazoles under study. A phenyl residue also contributes to the radioprotective effect. The influence of thiazoles on DNA biosynthesis on radiosensitive tissues plays an important role in the biochemical mechanism of their radioprotective action. 相似文献
5.
It was shown that different polysaccharides markedly vary in their toxicity, exert a radioprotective effect when administered both 24 h and 1-4 h before irradiation, enhance and prolong the radioprotective action of S-containing radioprotective agents, and inhibit DNA synthesis in bone marrow which, in all appearance, plays a certain role in the mechanism of their radioprotective action. 相似文献
6.
Il'in LA Andrianova IE Glushkov VA 《Radiatsionnaia biologiia, radioecologiia / Rossi?skaia akademiia nauk》2004,44(2):176-178
The influence of chitosan molecular mass (70, 10 and 5 kDa) on its radioprotective efficiency in mice experiments was studied. It was shown that chitosans with molecular masses of 70 and 10 kDa had similar radioprotective properties. The survival of mice increased up to 73% and 87% respectively at intravenous injection 15-30 min before a whole-body exposure to 137Cs gamma-radiation at a dose of 8 Gy (Cd97/30). Practically absolute loss of radioprotective activity occurred below a threshold of about 10 kDa. The results showed a high chitosan radioprotective activity in a wider range of molecular masses than it was supposed earlier. 相似文献
7.
Adenosine and a majority of adenine mononucleotides have a radioprotective action; adenine and 2'-deoxyadenosine have no radioprotective effect, and that of 3',5'-cAMP only approaches the detectable level. Ribo- and deoxyribonucleosides and nucleotides of guanine, uracil, thymine, and cytosine have no protective action. Dipyridamole increases and alkylxanthines block the radioprotective effect of adenosine. So it follows that the radioprotective effect is realized via A-receptors of the plasmatic membrane external surface. 相似文献
8.
It was shown that omega-hydroxylation of O-alkyl serotonin derivatives can slightly improve the radioprotective and pharmacological properties of these substances but fails to remove completely the unfavourable action of O-alkylation of serotonin. There is a close correlation between the radioprotective effect of 5-oxyalkoxytryptamines and their action on blood supply of mouse spleen. The introduction of the alkoxy-group or the tertiary amino-group into omega-position removes the radioprotective effect of 5-alkoxytryptamines. 相似文献
9.
The Bowman-Birk protease inhibitor has been reported to exert photo- and radioprotective activity. This effect was assigned to a cyclic nonapeptide sequence which is known to contain the amino acids responsible for the anti-chymotryptic activity of the BBI. The present study indicated that linearization of the nonapeptide resulted in a significant loss of anti-proteolytic activity, whereas the photo- and radioprotective capacity persisted. Substitution of the amino acids Leu or Ser of the nonapeptide, essential for the anti-proteolytic activity, with different amino acids, indicated that rather the hydrophobic features of the amino acids in this position than charge are critical to retain the photo- and radioprotective effect. These results suggest the existence of a bifunctional peptide sequence with anti-proteolytic and photo-/radioprotective capacity. However, the lack of correlation between the photo-/radioprotective activity and the anti-proteolytic activity within the peptides generated by modification of the linear nonapeptide argues for the existence of two closely colocalized domains within the nonapeptide responsible for photo-/radioprotection and protease inhibition. 相似文献
10.
The method of coupled estimation of the hypoxic and radioprotective effect has demonstrated that the hypoxic mechanism does not play an essential role in the radioprotective action of phenylephrine hydrochloride. 相似文献
11.
Iu Iu Chirkov M A Malatsidze A S Sobolev 《Nauchnye doklady vysshe? shkoly. Biologicheskie nauki》1985,(5):38-41
The radioprotective ability of adrenaline, noradrenaline and isoproterenol in various concentrations has been studied in experiments on cultured Chinese hamster fibroblasts in vitro. Radioprotective effect of isoproterenol is pronounced at 10(-8)M concentration; adrenaline and especially noradrenaline are effective at higher concentrations. The antagonist of beta-adrenergic receptors propranolol blocks the radioprotective effect of catecholamines on cells. The beta-adrenergic mechanism of catecholamines radioprotective action on the mammals cells is under discussion. 相似文献
12.
N B Pushkareva A V Nikol'ski? A N Koterov I V Filippovich 《Biulleten' eksperimental'no? biologii i meditsiny》1989,107(2):191-193
The effect of different chemical compounds on the cAMP/cGMP ratio in the bone marrow of mice and radioresistance of animals has been studied. It has been shown that all compounds possessing radioprotective properties give rise to the cAMP/cGMP ratio in the bone marrow of mice. No changes in cAMP and cGMP level were noted after the administration of nonradioprotective substances. The maximal radioprotective effect coincide in time with the largest increase of the cAMP/cGMP ratio. The injection of radioprotectors at different doses demonstrate clearly that only at radioprotective doses the increase in the cAMP/cGMP ratio takes place. The administration of some substances 2, 15 and 60 min after the irradiation of mice shows that the radioprotective effect, though modest, was evident only in one case of elevated cAMP/cGMP ratio (the injection of 2-Mercaptoethylamine 2 min after the irradiation). Evident radioprotective effect occurs at the cAMP/cGMP ratio of about 170-200%; the ratio of about 130-140% corresponds to small radioprotection. 相似文献
13.
alpha-Adrenoceptor agonists of both main groups, i. e. arylalkylamines and imidazolines, have a pronounced radioprotective effect. Their chemical analogs, which fail to stimulate alpha-adrenoceptors, do not protect mice. The effect of phenylephrine, adrenaline, and noradrenaline comes into play via alpha 1-adrenoceptors and that of clonidine, via alpha 2-adrenoceptors and also via alpha 1-adrenoceptors. Adrenoceptor agonists can probably manifest their radioprotective action via both subtypes of alpha-adrenoceptors. Possible intracellular mechanisms of the radioprotective action are discussed. 相似文献
14.
A study was made of the protective effect of some radioprotective agents against dominant lethal mutations (DLM) in postspermatogonial stages and reciprocal translocations (RT) in spermatogonia induced by gamma-radiation. Among the radioprotective agents used, cystaphos, a combination of cystamine and 5-MOT and a mixture of 6 components proved to be most effective against DLM, and cystaphos, gammaphos and cystamine combined with 5-MOT proved effective against RT. The degree of radioprotective efficacy was relatively low. The efficacy of cystamine in protecting against RT was higher with exposure of gonocytes of 18.5-day embryos than spermatogonia of pubertal animals. The degree of the radioprotective effect varied depending on the stage of spermatogenesis, and, in all cases, it was lower than that observed in studies of protection against lethal effects of ionizing radiation. 相似文献
15.
In experiments on mice a study was made of different substituents in the 4th position of the indole ring of 5-methoxytryptamines (5-MOT) on toxicity and radioprotective efficiency of the compounds of this class. It was shown that the administration of the amino-group to a mexamine molecule increased the preparation toxicity; the nitro-group somewhat diminished the toxic properties, and the acetylamino group did not change 5-MOT toxicity. A 5-MOT derivative with a nitro group possessed the strongest radioprotective action. The radioprotective efficiency of these compounds persisted for 1-2 h. 相似文献
16.
V K Mukhomorov 《Radiobiologiia》1986,26(4):557-559
Molecular mechanisms of radioprotective action of some substituted indolylalkylamines are discussed in terms of the statistical correlation analysis. It was established that electron and steric properties of the substituents are the factors influencing the radioprotective efficiency of these compounds. It was shown that the correlation obtained, relating the structure of the compounds to the radioprotective effect, may be applied in studies of the mechanism of action of the preparations and for the purposeful synthesis of new compounds. 相似文献
17.
V G Vladimirov I P Kamenko G A Poddubski? S M Smirnova L G Tarnopol'skaia 《Radiobiologiia》1986,26(4):495-498
The method of mathematical theory of experiment was used to find optimum variants of the radioprotective complex APAETP + mexamine. The character of their pharmacological interaction, depending on their dose ratio, was determined. It is suggested that it is conditioned by the specific role of different mechanisms involved in the radioprotective effect. 相似文献
18.
In experiments with mongrel male rats exposed to whole-body gamma-radiation (7, 9 and 11 Gy) the radioprotective effect of enterally administered Sophora japonica and its combination with an antioxidant vitamin complex was investigated. The radioprotective agents applied were shown to produce a synergistic effect. 相似文献
19.
Heating of mouse bone marrow cells up to 42 degrees C was shown to increase their radiosensitivity (DMF = 0.80 +/- 0.12). At this temperature, the radioprotective efficiency of cysteamine was lost completely (DMF = 0.78 +/- 0.09), and radioprotective activity of d,l-isoproterenol significantly decreased (DMF declined from 2.41 +/- 0.23 to 1.67 +/- 0.16). It is assumed that the radioprotective effect of cysteamine on mammalian cells is associated with the processes of the postirradiation DNA repair for just these processes are inhibited by heating. The mechanism of action of a beta-agonist of isoproterenol is perhaps only partially associated with DNA repair. 相似文献
20.
M Pospísil J Netíková I Pipalová K Volenec 《Physiological research / Academia Scientiarum Bohemoslovaca》1991,40(4):445-452
The slight radioprotective action of inosine, when injected intraperitoneally to mice shortly before gamma-irradiation, can be enhanced by the administration of magnesium aspartate. This effect can be explained by the additivity of the vasodilatory actions of both agents. Inosine increases the radioprotective effectiveness of hypobaric hypoxia (10% O2), probably due to the additivity of the hypoxic effects in radiosensitive tissues. Acute hypoxic toxicity, however, is decreased by inosine administration. The cumulation of radioprotective effects of inosine and of its antihypoxic action in vitally important organs can have a favourable influence in hypoxic radiotherapy. 相似文献