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101.
Martina Bancirova 《Luminescence》2011,26(6):685-688
Reactive oxygen species (ROS) are presently thought to play important role in an increasing number of the physiological and pathological processes in living organisms. Various chemiluminescent (CL) compounds have been studied in order to find suitable and specific probes for the detection of particular ROS species. The CL of luminol is known to be non‐specific and can be induced by various oxidants. Two Cypridina luciferin analogues, CLA and MCLA, have been used for the detection of ROS in vivo. CLAs are thought to emit light only when reacting with superoxide and singlet oxygen. It is possible to distinguish the particular ROS by using a specific quencher or scavenger, e.g. superoxide dismutase (SOD) or sodium azide (NaN3). The CL reactions of luminol (3‐aminophthalhydrazide), CLA [2‐methyl‐6‐phenyl‐3,7‐dihydroimidazo(1,2α) pyrazin‐3‐one] and MCLA [2‐methyl‐6‐(p‐methoxyphenyl)‐3,7‐dihydroimidazo(1,2α) pyrazin‐3‐one] were studied in three hydrogen peroxide decomposition systems (H2O2–HRP; H2O2–CuSO4; and H2O2–NaOCl). The measurements were carried out in phosphate buffer, pH 7.4, at 25 °C, using a luminometer (Fluoroskan Ascent FL and Sirius C). NaN3 was used as the specific quencher of singlet oxygen. The results demonstrate that the proclaimed specifity of the CL of Cypridina luciferin analogues towards singlet oxygen has to be discussed. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
102.
103.
A.?M.?R.?FerrieEmail author J.?Dirpaul P.?Krishna Krochko W.?A.?Keller 《In vitro cellular & developmental biology. Plant》2005,41(6):742-745
Summary Experiments were conducted to determine the effects of brassinosteroids on microspore embryogenesis in Brassica species. Two compounds, 24-epibrassinolide (EBR) and brassinolide (BL), were evaluated. An increase in embryogenesis was
observed in all Brassica napus lines evaluated, including Topas 4079 and several recalcitrant cultivars: Garrison, Westar, and Allons. Microspore embryogenesis,
calculated as the number of embryos at 21 d of culture, was increased in the recalcitrant cultivars up to 12 times that of
the control. An increase in microspore embryogenesis was also observed for B. juncea when EBR or BL was added to the culture medium. In constrast, no significant increases in embryogenesis was observed for
several other Brassica species evaluated (i.e. B. carinata, B. nigra, and B. rapa). The addition of brassinosteroids to the induction media did not affect the subsequent conversion of the embryos to plantlets,
but did appear to influence chromosome doubling. 相似文献
104.
L.?N.?Rogosaanvar@niboch.nsc.ru" title="rogoza@niboch.nsc.ru anvar@niboch.nsc.ru" itemprop="email" data-track="click" data-track-action="Email author" data-track-label="">Email author N.?F.?Salakhutdinov G.?A.?Tolstikov 《Russian Journal of Bioorganic Chemistry》2005,31(6):507-520
This review, issued in two parts, describes the information on the structure and biological activity of animal alkaloids derived from polymethyleneamines and produced by marine organisms, wasps, spiders, and microorganisms. Animal alkaloids are outstanding models for developing methods and drugs for the treatment of many human diseases. In the first part, we consider compounds produced by marine and microbial organisms. Some promising synthetic analogues of these alkaloids are used in developing modern preparations for the chelate therapy of excessive blood iron content and antituberculosis, antiproliferative, and immunosuppressive drugs. 相似文献
105.
A.?M.?KritzynEmail author J.?Vepsalainen V.?V.?Komissarov 《Russian Journal of Bioorganic Chemistry》2005,31(3):256-262
New polymethylene nucleoside analogues with a β-dioxo function in the ω-position of their hydro-carbon chain, [7-(2-oxocyclohexyl)-7-oxoheptyl]purines, were synthesized, and their physicochemical properties were studied.__________Translated from Bioorganicheskaya Khimiya, Vol. 31, No. 3, 2005, pp. 288–294.Original Russian Text Copyright © 2005 by Kritzyn, Vepsalainen, Komissarov.For communication III, see [1]. 相似文献
106.
107.
I.?A.?Il'ichevaEmail author Yu.?P.?Zarubin P.?A.?Kostin D.?V.?Mirgorodskii P.?P.?Purygin V.?L.?Florent'ev 《Russian Journal of Bioorganic Chemistry》2005,31(5):439-452
Conformational models of the active site of adenosine deaminase (ADA) and its complexes in the basic state with adenosine and 13-isosteric analogues of the aza, deaza, and azadeaza series were constructed. The optimization of the conformational energy of the active site and the nucleoside bound with it in the complex was achieved in the force field of the whole enzyme [the structure of ADA complex with 1-deazaadenosine (1ADD) was used] within the molecular mechanics model using the AMBER 99 potentials. The stable conformational states of each of the complexes, as well as the optimal conformation of ADA in the absence of ligand, were determined. It was proved that the conformational state that is close to the structure of the ADA complex with 1ADD known from X-ray study corresponds to one of the local minima of the potential surface. Another, a significantly deeper minimum was determined; it differs from the first minimum by the mutual orientation of side chains of amino acid residues. A similar conformational state is optimal for the ADA active site in the absence of bound ligand. A qualitative correlation exists between the values of potential energies of the complexes in this conformation and the enzymatic activity of ADA toward the corresponding nucleosides. The dynamics of conformational conversions of the active site after the binding of substrate or its analogues, as well as the possibility of the estimation of the inhibitory properties of nucleosides on the basis of calculations, are discussed. 相似文献
108.
A.?L.?KhandazhinskayaEmail author M.?K.?Kukhanova M.?V.?Jasko 《Russian Journal of Bioorganic Chemistry》2005,31(4):352-356
N-(9-Fluorenylmethoxycarbonyl)-ω-aminoalkyl-, N-(9-fluorenylmethoxycarbonyl)-8-amino-3,6-dioxaoctyl, and N-[(9-fluorenylmethoxycarbonyl)-6-aminohexanoyl]-2-aminoethyl triphosphates were synthesized. All of them were shown to be the substrates of the calf thymus terminal deoxynucleotidyl transferase. Their substrate properties depend on the length and structure of the linker between the 9-fluorenylmethoxycarbonyl and triphosphate moieties.__________Translated from Bioorganicheskaya Khimiya, Vol. 31, No. 4, 2005, pp. 394–398.Original Russian Text Copyright © 2005 by Khandazhinskaya, Kukhanova, Jasko. 相似文献
109.
Jesper Wengel Michael Petersen Miriam Frieden Troels Koch 《International journal of peptide research and therapeutics》2005,10(3):237-253
Summary Preparation of LNA nucleosides requires a number of synthetic steps but very efficient procedures have been developed, as have protocols for synthesis of LNA oligonucleotides on automated DNA synthesizers. In all cases, LNA oligonucleotides have exhibited good aqueous solubility as would be expected from their close structural resemblance to the natural nucleic acids. The universality of LNA mediated high-affinity and specific hybridization has been demonstrated extensively with a large number of duplex forming LNA-oligonucleotides. Most importantly, most of the members of the LNA molecular family have been shown to exert their substantial affinity increase (i) in combination with standard DNA, RNA and contemporary analogues and (ii) whether inserted as single nucleosides in an oligonucleotide or as blocks of contiguous nucleotides, an important point. The works on TFOs is expanding the usefulness of LNA to double strand recognition and it has been demonstrated that LNA it is a promising structure for further base modifications in the pursuit of global sequence specific recognition of DNA. 相似文献
110.