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41.
42.
A. V. Tugarova E. P. Vetchinkina E. A. Loshchinina A. G. Shchelochkov V. E. Nikitina A. A. Kamnev 《Microbiology》2013,82(3):352-355
Effect of selenium(+4) as selenite (Se 3 2? ) on two Azospirillum brasilense strains, which occupy different ecological niches (an epiphyte Sp7 and a facultative endophyte Sp245), was studied. The cultures grown in the medium with sodium selenite exhibited intense red coloration. Transmission electron microscopy and X-ray fluorescence analysis revealed accumulation of elementary selenium within the cells of both strains as nanoparticles 50–400 nm in diameter. The ability to reduce inorganic selenium(+4) to elementary selenium (as nanoparticles) has not been previously reported for azospirilla. Our results indicate the possibility to apply Azospirillum strains as microsymbionts for phytoremediation of, and cereal cultivation on, selenium-contaminated soils. The ability of azospirilla to synthesize selenium nanoparticles may be of interest for nanobiotechnology. 相似文献
43.
R. Campos‐Herrera E.G. Johnson F.E. EL‐Borai R.J. Stuart J.H. Graham L.W. Duncan 《The Annals of applied biology》2011,158(1):55-68
Quantitative real‐time PCR (qPCR) techniques are being increasingly used to provide accurate and reliable methods to identify and quantify cryptic organisms in soil ecology. Entomopathogenic nematode (EPN) diversity in Florida is known to be extensive and our phylogenetic studies of the D2D3 and ITS regions showed the occurrence of an additional species‐complex in the Steinernema glaseri‐ group in widely separated locations of the peninsula. To address ecological studies, we developed and used qPCR assays to detect and quantify six species of EPN that are naturally distributed in Florida citrus orchards (Steinernema diaprepesi, Steinernema riobrave, Heterorhabditis indica, Heterorhabditis zealandica, Heterorhabditis floridensis and an undescribed species in the S. glaseri group) and an exotic species, S. glaseri. Species‐specific primers and TaqMan® probes were designed from the ITS rDNA region. No nonspecific amplification was observed in conventional or qPCR when the primers and probes were tested using several populations of each of the Florida species and other exotic EPN species. Standard curves were established using DNA from pure cultures. We optimised a protocol for extracting nematodes and DNA from soil samples that can detect one EPN added to nematode communities recovered by conventional extraction protocols. A survey of an 8‐ha orchard in April 2009 compared the EPN spatial patterns derived from qPCR to that obtained by baiting soil samples with Galleria mellonella larvae. The patterns were also compared to those derived from the same site in 2000–01 by repeatedly (12 sampling events) baiting soil in situ with caged larvae of the root weevil Diaprepes abbreviatus. The qPCR assay was more efficient than the Galleria baiting method for detecting the EPN species composition in population mixtures. Moreover, the spatial patterns of EPN in this orchard were remarkably stable over the course of nearly a decade. The pattern of H. zealandica detected at the site 8 years earlier was related to those derived by qPCR (P = 0.002) and from sample baiting (P = 0.02). The spatial pattern of H. indica derived from qPCR, but not that from sample baiting, was also related to the earlier pattern (P = 0.01). The qPCR assay developed here is a fast, affordable and accurate method to detect and quantify these EPN species in soil and offers great potential for studying the ecology of EPN. 相似文献
44.
45.
A. O. D. Willows L. A. Nikitina V. V. Bezuglov N. M. Gretskaya G. A. Buznikov 《Russian Journal of Developmental Biology》2000,31(2):106-112
Ritanserin and inmecarb hydrochloride, antagonists of serotonin, act cytostatically and teratogenically on early embryos ofTritonia diomedea, a nudibranch mollusk. On the basis of a pharmacological analysis and the type of developmental abnormalities observed, this
action appears to be due to disturbances in the functional activity of endogenous serotonin and is associated with damage
to the cytoskeleton. The effects of ritanserin and inmecarb are prevented or attenuated by lipophilic serotonin analogs (serotoninamides
of polyenoic fatty acids), as well as by polypeptides isolated from neurons Pd5 and Pd6 of the pedal ganglia of the adultTritonia. In late embryos (stage of veligers), serotonin and to a lesser extent its lipophilic analogs strongly increase embryonic
motility. This effect of serotonin is potentiated by some neuropeptides and inhibited by others. These results provide evidence
for functional interaction between serotonin and neuropeptides in the control processes of embryogenesis. 相似文献
46.
Tauqeer Ahmad Yasir Sobia Aslam Muhammad Shahid Rizwan Allah Wasaya Muhammad Ateeq Muhammad Naeem Khan Sikander Khan Tanveer Walid Soufan Basharat Ali Allah Ditta Arpna Kumari Ayman EL Sabagh 《Phyton》2022,91(11):2491-2504
In soil biota, higher and enduring concentration of heavy metals like cadmium (Cd) is hazardous and associated
with great loss in growth, yield, and quality parameters of most of the crop plants. Recently, in-situ applications of
eco-friendly stabilizing agents in the form of organic modifications have been utilized to mitigate the adverse
effects of Cd-toxicity. This controlled experiment was laid down to appraise the imprints of various applied
organic amendments namely poultry manure (PM), farmyard manure (FYM), and sugarcane press mud (PS)
to immobilize Cd in polluted soil. Moreover, phytoavailability of Cd in wheat was also accessed under an alkaline
environment. Results revealed that the addition of FYM (5–10 ton ha-1
) in Cd-contaminated soil significantly
increased germination rate, leaf chlorophyll content, plant height, spike length, biological and grain yield amongst
all applied organic amendments. Moreover, the addition of FYM (5–10 ton ha-1
) also reduced the phytoavailability of Cd by 73–85% in the roots, 57–83% in the shoots, and 81–90% in grains of wheat crop. Thus, it is affirmed
that incorporation of FYM (5–10 ton ha-1
) performed better to enhance wheat growth and yield by remediating
Cd. Thus, the application of FYM (5–10 ton ha-1
) reduced the toxicity induced by Cd to plants by declining its
uptake and translocation as compared to all other applied organic amendments to immobilize Cd under sandy
alkaline polluted soil. 相似文献
47.
Nikitina Veronika A. Zakharova Maria V. Trofimov Alexander N. Schwarz Alexander P. Beznin Gleb V. Tsikunov Sergei G. Zubareva Olga E. 《Biochemistry. Biokhimii?a》2021,86(6):761-772
Biochemistry (Moscow) - According to the two-hit hypothesis of psychoneuropathology formation, infectious diseases and other pathological conditions occurring during the critical periods of early... 相似文献
48.
Nikitina I. B. Goretova I. V. Fedoseev I. V. 《Russian Journal of Bioorganic Chemistry》2021,47(5):1014-1019
Russian Journal of Bioorganic Chemistry - This article is devoted to the patenting of proteins, containing D-isoforms of amino acids, its potential problems and perspectives. Today, technologies... 相似文献
49.
Imre Mäger Emelía Eiríksdóttir Samir EL Andaloussi Ülo Langel 《生物化学与生物物理学报:生物膜》2010,1798(3):338-1672
Cell-penetrating peptides (CPPs) have shown great potency for cargo delivery both in vitro and in vivo. Different biologically relevant molecules need to be delivered into appropriate cellular compartments in order to be active, for instance certain drugs/molecules, e.g. antisense oligonucleotides, peptides, and cytotoxic agents require delivery into the cytoplasm. Assessing uptake mechanisms of CPPs can help to develop novel and more potent cellular delivery vectors, especially in cases when reaching a specific intracellular target requires involvement of a specific internalization pathway. Here we measure the overall uptake kinetics, with emphasis on cytoplasmic delivery, of three cell-penetrating peptides M918, TP10 and pVec using a quenched fluorescence assay. We show that both the uptake levels and kinetic constants depend on the endocytosis inhibitors used in the experiments. In addition, in some cases only the internalization rate is affected by the endocytosis inhibitors while the total uptake level is not and vice versa, which emphasizes importance of kinetic studies when assessing the uptake mechanisms of CPPs. Also, there seems to be a correlation between lower total cellular uptake and higher first-order rate constants. Furthermore, this may indicate simultaneous involvement of different endocytic pathways with different efficacies in the internalization process, as hypothesized but not shown earlier in an uptake kinetics assay. 相似文献
50.
R N Khodanova L S Seslavina N N Golubeva V A Zuyeva O N Kutkova V V Maltseva T I Nikitina 《Journal of hygiene, epidemiology, microbiology, and immunology》1989,33(4):463-469
An efficient method for the treatment of drug allergy was proposed and practically implemented. The method consists in autologous venous blood being lyzed with sterile bidistilled water at a ratio of 5:1 and injected subcutaneously and partially intradermally into the reflexogenic zones of the back 2-3 cm from the spinal column. During the first week of treatment, increasing doses were injected (3 to 10 ml), whereas during the second week the doses decreased from 10 to 3 ml. Following treatment the patients felt better and featured enhanced working ability as well as markedly declined susceptibility to common colds. The most informative immunological indicators were chosen to evaluate the efficiency of therapy. 相似文献