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11.
T. T. Efremova E. V. Chumanova N. V. Trubacheeva V. S. Arbuzova I. A. Belan L. A. Pershina 《Russian Journal of Genetics》2016,52(2):146-153
With the use of allele-specific primers developed for the VRN1 loci, the allelic diversity of the VRN-A1, VRN-B1, and VRN-D1 genes was studied in 148 spring common wheat cultivars cultivated under the conditions of western Siberia. It was demonstrated that modern Western Siberian cultivars have the VRN-A1a allele, which is widely distributed in the world (alone or in combination with the VRN-B1a and VRN-B1c alleles). It was established that the main contribution in acceleration of the seedling–heading time is determined by a dominant VRN-A1a allele, while the VRNA1b allele, on the contrary, determines later plant heading. Cultivars that have the VRN-A1b allele in the genotype are found with a frequency of 8%. It was shown that cultivars with different allele combinations of two dominant genes (VRN-A1a + VRN-B1c and VRN-A1a + VRN-B1a) are characterized by earlier heading and maturing. 相似文献
12.
AP Shoko SM Limbu HA Lamtane MA Kishe-Machumu B Sekadende EE Ulotu 《African Journal of Aquatic Science》2019,44(1):15-24
Aquaculture practices from sub-Saharan Africa are characterised by low production, owing to improper technology. Production can be increased through integrating fish farming with other existing on-farm activities, particularly livestock husbandry. We assessed the role of fish-poultry integration on all male Nile tilapia, Oreochromis niloticus growth performance, yields and economic benefits among smallholder farmers in sub-Saharan Africa, Tanzania. The study also compared phytoplankton species composition, abundance and biomass between the fish-poultry integration and non-integrated system. After 180 days of the experiment, all male O. niloticus cultured under fish-poultry integration exhibited significantly higher growth rates than those in the non-integrated system (p < 0.05). Gross fish yield (GFY), net fish yield (NFY) and net annual yields (NAY) obtained from fish-poultry integration were significantly higher than those from non-integrated system (p < 0.05). Partial enterprise budget analysis revealed that fish-poultry integration was more profitable than the non-integrated system. Moreover, fish-poultry integrated system produced significantly higher phytoplankton abundance and biomass than those from the non-integrated system. Results demonstrate that rural smallholder farmers can achieve higher growth rate, farm net yields and income by integrating all male O. niloticus with other on-farm activities than practising a stand-alone fish culture system. 相似文献
13.
Kurbatova EA Semenov BF Egorova NB Efremova VN Gruber IM Semenova IB Kushchenko OM 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》2004,(3):34-39
The experimental study of the immunostimulating activity of therapeutic bacterial polycomponent vaccine VP-4 and prophylactic vaccine grippol, introduced both separately and in combination, on mice infected with Salmonella typhimurium, used as a model. Both preparations were found to produce an immunomodulating effect. The combined subcutaneous injection of VP-4 and grippol did not decrease their immunostimulating activity, but their separate administration at an interval of 14 days resulted in essential decrease in the protective activity of each of these two preparations. As shown on the model of Klebsiella infection in mice, challenged 4 weeks after immunization, VP-4 ensured the survival of 78.6% of mice, while after the injection of grippol their survival rate was not different from that of the group of intact animals. The evaluation of the immunostimulating activity of these preparations under the conditions of the prophylaxis of influenza and acute respiratory infections in organized groups of children revealed that the use of VP-4 alone or grippol in combination with VP-4 considerably decreased the number of secondary bacterial complications in children. 相似文献
14.
A poorly studied species of hexaploid wheat Triticum petropavlovskyi Udacz. et Migusch. was compared with common wheat Triticum aestivum L. by means of monosomic and genetic analyses of F2 hybrids. Triticum petropavlovskyi was found to carry 13 dominant genes determining its morphological and physiological characters and regular bivalent conjugation of chromosomes. These genes were allelic to the respective genes of common wheat and were located in the same chromosomes. The modes of gene interaction were also the same. There was simple dominance for most genes studied and complementary interaction for the genes of hybrid dwarfism and hybrid necrosis. Triticum petropavlovskyi had the following dominant genes: Hg (downy glume); Rg1 (red glume color); Hl (downy leaf); Hn (downy node); Pa (pubescent auricles); Q (speltlike ears); D1 (grass-clump dwarfism); Ne1 (hybrid necrosis); Ph1 and Ph2 (genes of bivalent conjugation preventing homoeologous chromosomes from pairing); and Vrn1, Vrn2, Vrn3, and Vrn4 (genes of the spring habit). The gene Vrn1, which caused an increase in ear emergence time and a pronounced response to vernalization, was poorly expressed. T. petropavlovskyi was earlier demonstrated to have a species-specific gene P or Eg (elongated glume), which was not allelic to the gene Eg of the tetraploid T. polonicum L. The data obtained indicate that T. petropavlovskyi has originated from T. aestivum via mutations. 相似文献
15.
Karyotypic variability has been investigated for nonimmortalized human embryonic lung cell line MRC-5, cultivated with Acholeplasma laidlawii strain PG-8 for 15-45 days. The character of cell distribution for chromosome number did not change during this time. In all investigated variants the number of polyploid cells increased considerably with the lengthening of the term after decryoconservation. The number of chromosomal aberrations in 15-45 days contaminated cells increased significantly as compared to the control at the expense of dicentrics (telomeric associations). The number of dicentrics had a tendency to increase with the lengthening of the term of contamination. Thus, in 45 days the number of dicentrics increased twice as much as that in 15 days. The increase of polyploids may be due presumably to the specific character of karyotypic variability in nonimmortalized cell lines with the long-term cultivation. Our present and previous results made it possible to suppose that the formation of dicentrics (telomeric associations) in nonimmortalized "markerless" cell line, following the long-term mycoplasmal contamination, may prove additionally the role played by dicentrics in cell adaptation to in vitro conditions whatever the degree of transformation may be--nonimmortalized line or immortalized nontumorogenic or high tumorogenic lines. 相似文献
16.
Background
A recent epidemiological study demonstrated a reduced risk of lung cancer mortality in breast cancer patients using antiestrogens. These and other data implicate a role for estrogens in lung cancer, particularly nonsmall cell lung cancer (NSCLC). Approximately 61% of human NSCLC tumors express nuclear estrogen receptor β (ERβ); however, the role of ERβ and estrogens in NSCLC is likely to be multifactorial. Here we tested the hypothesis that proteins interacting with ERβ in human lung adenocarcinoma cells that respond proliferatively to estradiol (E2) are distinct from those in non-E2-responsive cells.Methods
FLAG affinity purification of FLAG-ERβ-interacting proteins was used to isolate ERβ-interacting proteins in whole cell extracts from E2 proliferative H1793 and non-E2-proliferative A549 lung adenocarcinoma cell lines. Following trypsin digestion, proteins were identified using liquid chromatography electrospray ionization tandem mass spectrometry (LC-MS/MS). Proteomic data were analyzed using Ingenuity Pathway Analysis. Select results were confirmed by coimmunoprecipitation.Results
LC-MS/MS identified 27 non-redundant ERβ-interacting proteins. ERβ-interacting proteins included hsp70, hsp60, vimentin, histones and calmodulin. Ingenuity Pathway Analysis of the ERβ-interacting proteins revealed differences in molecular and functional networks between H1793 and A549 lung adenocarcinoma cells. Coimmunoprecipitation experiments in these and other lung adenocarcinoma cells confirmed that ERβ and EGFR interact in a gender-dependent manner and in response to E2 or EGF. BRCA1 interacted with ERβ in A549 cell lines and in human lung adenocarcinoma tumors, but not normal lung tissue.Conclusion
Our results identify specific differences in ERβ-interacting proteins in lung adenocarcinoma cells corresponding to ligand-dependent differences in estrogenic responses.17.
Sigrid NW Vorrink Helianthe SM Kort Thierry Troosters Jan-Willem J Lammers 《Respiratory research》2011,12(1):33
Background
Persons with Chronic Obstructive Pulmonary Disease (COPD), performing some level of regular physical activity, have a lower risk of both COPD-related hospital admissions and mortality. COPD patients of all stages seem to benefit from exercise training programs, thereby improving with respect to both exercise tolerance and symptoms of dyspnea and fatigue. Physical inactivity, which becomes more severe with increasing age, is a point of concern in healthy older adults. COPD might worsen this scenario, but it is unclear to what degree. This literature review aims to present the extent of the impact of COPD on objectively-measured daily physical activity (DPA). The focus is on the extent of the impact that COPD has on duration, intensity, and counts of DPA, as well as whether the severity of the disease has an additional influence on DPA.Results
A literature review was performed in the databases PubMed [MEDLINE], Picarta, PEDRO, ISI Web of Knowledge and Google scholar. After screening, 11 studies were identified as being relevant for comparison between COPD patients and healthy controls with respect to duration, intensity, and counts of DPA. Four more studies were found to be relevant to address the subject of the influence the severity of the disease may have on DPA. The average percentage of DPA of COPD patients vs. healthy control subjects for duration was 57%, for intensity 75%, and for activity counts 56%. Correlations of DPA and severity of the disease were low and/or not significant.Conclusions
From the results of this review, it appears that patients with COPD have a significantly reduced duration, intensity, and counts of DPA when compared to healthy control subjects. The intensity of DPA seems to be less affected by COPD than duration and counts. Judging from the results, it seems that severity of COPD is not strongly correlated with level of DPA. Future research should focus in more detail on the relation between COPD and duration, intensity, and counts of DPA, as well as the effect of disease severity on DPA, so that these relations become more understandable. 相似文献18.
Background
Microarray experiments, as well as other genomic analyses, often result in large gene sets containing up to several hundred genes. The biological significance of such sets of genes is, usually, not readily apparent. 相似文献19.
Kurdyukov S Faust A Trenkamp S Bär S Franke R Efremova N Tietjen K Schreiber L Saedler H Yephremov A 《Planta》2006,224(2):315-329
In plants, extracellular matrix polymers built from polysaccharides and cuticular lipids have structural and protective functions. The cuticle is found to be ten times thinner in Arabidopsis thaliana (L.) Heynh than in many other plants, and there is evidence that it is unusual in having a high content of α-,ω-dicarboxylic fatty acids (FAs) in its polyesters. We designated the new organ fusion mutant hth-12 after it appeared to be allelic to adhesion of calyx edges (ace) and hothead (hth), upon molecular cloning of the gene by transposon tagging. This mutant is deficient in its ability to oxidize long-chain ω-hydroxy FAs to ω-oxo FAs, which results in leaf polyesters in decreased α-,ω-dicarboxylic FAs and increased ω-hydroxy FAs. These chemical phenotypes lead to disorder of the cuticle membrane structure in hth-12. ACE/HTH is a single-domain protein showing sequence similarity to long-chain FA ω-alcohol dehydrogenases from Candida species, and we hypothesize that it may catalyze the next step after cytochrome P450 FA ω-hydroxylases in the ω-oxidation pathway. We show that ACE/HTH is specifically expressed in epidermal cells. It appears very likely therefore that the changes in the amount of α-,ω-dicarboxylic FAs in hth-12 reflect the different composition of cuticular polyesters. The ACE/HTH gene is also expressed in root epidermal cells which do not form a polyester membrane on the exterior surface, thereby making it possible that the end products of the pathway, α-,ω-dicarboxylic FAs, are generally required for the cross-linking that ensures the integrity of the outer epidermal cell wall. 相似文献
20.
Lakhin AV Kazakov AA Makarova AV Pavlov YI Efremova AS Shram SI Tarantul VZ Gening LV 《Nucleic acid therapeutics》2012,22(1):49-57
Human DNA-polymerase iota (Pol ι) is an extremely error-prone enzyme and the fidelity depends on the sequence context of the template. Using the in vitro systematic evolution of ligands by exponential enrichment (SELEX) procedure, we obtained an oligoribonucleotide with a high affinity to human Pol ι, named aptamer IKL5. We determined its dissociation constant with homogenous preparation of Pol ι and predicted its putative secondary structure. The aptamer IKL5 specifically inhibits DNA-polymerase activity of the purified enzyme Pol ι, but did not inhibit the DNA-polymerase activities of human DNA polymerases beta and kappa. IKL5 suppressed the error-prone DNA-polymerase activity of Pol ι also in cellular extracts of the tumor cell line SKOV-3. The aptamer IKL5 is useful for studies of the biological role of Pol ι and as a potential drug to suppress the increase of the activity of this enzyme in malignant cells. 相似文献