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V. N. Orlov V. B. Sycheva E. V. Cherepanova Yu. M. Borisov 《Russian Journal of Genetics》2013,49(4):417-427
The contact points of four karyotypic races (St. Petersburg, Moscow, Seliger and West Dvina) of the common shrew Sorex araneus L. were studied at the Valdai Hills (European Russia) in an area unimpeded by geographic barriers. The populations of the races are separated by narrow hybrid zones that represent the most complex heterozygous hybrid karyotypes. At these points of contact, the morphometric differentiation of karyotype races was examined in 12 cranial measurements in 190 shrews of a known karyotype. A comparison of the mean values in studied samples of immature shrews revealed statistically significant differences and the correlation of some measurements which describe the level of musculus temporalis. It has been proposed that morphometric differences in the karyotypic races were preserved and accumulated because of a 50% reduction of the frequencies of hybrids. The deviation from the Hardy-Weinberg ration in the frequencies of the genotype and haploid sets of chromosomes in the hybrid zones can be attributed to a number of fatalities of hybrid embryos or the nonrandom mating of karyotypic races. The ethological isolation might arise in the evolution of some karyotypic races from the reduced fitness of the hybrids. 相似文献
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Netesova IG Swenson PD Osipova LP Kiselev NN Posukh OL Cherepanova NS Kazakovtseva MA Kashinskaia IuO Netesov SV 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》2001,(2):29-33
Blood samples taken from 231 native inhabitants of the village of Mendur-Sokkon located in the Republic of Altai (South-Western Siberia, Russia) were tested for the presence of virus hepatitis B (HBV) markers. 31 samples (13.4%) were found to contain HBsAg, 111 samples (48.05%) were found to contain total anti-HBc antibodies, 123 samples (53.24%) were found to contain anti-HBs antibodies and 15 blood samples (6.49%), anti-HBc antibodies without anti-HBs antibodies and HBsAg. The age-dependent distribution of the occurrence of HBV markers among the aboriginal population of the South Altal remained unchanged (69.9 +/- 7.9%) for the last 50 years. The vertical and horizontal routes of HBV transmissions were noted. The data obtained in this study are indicative of a highly endemic character of HBV of the territory of Mendur-Sokkon. HBsAg-positive blood samples were taken for HBsAg subtyping with the use of a panel of monoclonal antibodies. Two subtypes of HBsAg were detected: ayw1-2 and ayw3varB with the occurrence of 92.6% and 7.4%, i.e. distributed in the ratio 25/2. 相似文献
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A wide-ranging examination of plastid (pt)DNA sequence homologies within
higher plant nuclear genomes (promiscuous DNA) was undertaken. Digestion
with methylation-sensitive restriction enzymes and Southern analysis was
used to distinguish plastid and nuclear DNA in order to assess the extent
of variability of promiscuous sequences within and between plant species.
Some species, such as Gossypium hirsutum (cotton), Nicotiana tabacum
(tobacco), and Chenopodium quinoa, showed homogenity of these sequences,
while intraspecific sequence variation was observed among different
cultivars of Pisum sativum (pea), Hordeum vulgare (barley), and Triticum
aestivum (wheat). Hypervariability of plastid sequence homologies was
identified in the nuclear genomes of Spinacea oleracea (spinach) and Beta
vulgaris (beet), in which individual plants were shown to possess a unique
spectrum of nuclear sequences with ptDNA homology. This hypervariability
apparently extended to somatic variation in B. vulgaris. No sequences with
ptDNA homology were identified by this method in the nuclear genome of
Arabidopsis thaliana.
相似文献
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A survey was conducted to determine the levels of fumonisins B1 and B2 in corn and corn-based products available in Colombia
for human and animal consumption. A total of 120 samples were analyzed by acetonitrile-water extraction, cleanup with a strong-anion-exchange
column, and liquid chromatography with o-phthaldialdehyde-2-mercaptoethanol derivatization and fluorescence detection. The
samples of corn and corn-based products for animal intake were taken at different feed manufacturing plants, whereas the samples
used for human foods where purchased from local retail stores. The number of positive samples for fumonisin B1 was 20.0% higher
in corn and corn-based products for animal intake (75.0%) than in corn and corn-based products for human consumption (55.0%).
The levels of fumonisin B1 were also higher in corn and corn-based products for animal intake (mean = 694 μg/kg; range = 32–2964
μg/kg), than in corn and corn-based products for human intake (mean = 218 μg/kg; range = 24–2170 μg/ kg). The incidence and
levels of fumonisin B2 were lower than those for fumonisin B1. Corn and corn-based products for animal consumption had an
incidence of fumonisin B2 of 58.3%, with a mean value of 283 μg/kg, and a range of 44–987 μg/kg. The incidence of fumonisin
B2 in corn-based products for human intake was 35.0%, with a mean value of 118 μg/kg and a range of 21–833 μg/kg. The highest
incidence and levels of fumonisins were found in samples of hominy feed, with concentrations ranging from 86 to 2964 μg/kg
fumonisin B1 and 57 to 987 μg/kg fumonisin B2. 相似文献
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I. V. Maksimov E. A. Cherepanova O. B. Surina 《Russian Journal of Plant Physiology》2010,57(1):124-130
Effects of chitooligosaccharides (COS) on the activity of peroxidase and its isoenzyme composition were investigated in cocultures
of wheat calli (Triticum aestivum L.) with common bunt fungal pathogen (Tilletia caries (DC) Tul.). COS elevated the activity of readily soluble form of peroxidase: at concentrations of 0.01 and 1 mg/l, peroxidases
with isoelectric points (pI) of about 3.5 and 9.8 and at concentration of 100 mg/l—those with pI of 4.3–5.2 were activated. It was shown that treatment with COS boosted the resistance of wheat calli to T. caries, inducing the accumulation in the cell wall of pathogen-specific isoperoxidases, especially its anionic isoform with pI ∼ 3.5. The ultimate indicator of defense responses is quick lignification of cultured cell walls under the effect of COS
in the contamination area. 相似文献
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Here we studied the inhibition of the catalytic domain of Dnmt3a methyltransferase (Dnmt3a-CD) by DNA duplexes containing
the mechanism-based inhibitor pyrimidine-2(1H)-one (P) instead of the target cytosine. It has been shown that conjugates of Dnmt3a-CD with P-DNA (DNA containing pyrimidine-2(1H)-one) are not stable to heating at 65°C in 0.1% SDS. The yield of covalent intermediate increases in the presence of the
regulatory factor Dnmt3L. The importance of the DNA minor groove for covalent intermediate formation during the methylation
reaction catalyzed by Dnmt3a-CD has been revealed. P-DNA was shown to inhibit Dnmt3a-CD; the IC50 is 830 nM. The competitive mechanism of inhibition of Dnmt3a-CD by P-DNA has been elucidated. It is suggested that therapeutic effect of zebularine could be achieved by inhibition of not only
Dnmt1 but also Dnmt3a. 相似文献
9.
Tiuriaeva II Mirgorodskaia OA Cherepanova OA Podol'skaia EP Serebriakova MV Ivanov VA 《Tsitologiia》2005,47(12):1039-1047
The laminin affinity chromatography was used for isolating laminin-binding proteins from the plasma membrane of Zajdela hepatoma cells synthesizing laminin. These were components with mol. weights about 80, 67, 60, 55, 52, 48 and 43 kDa. The isolation of laminin integrin receptors from plasma membranes of Zajdela hepatoma cells in the presence of MnCl2 detected only a protein with mol. weight about 80 kDa in EDTA-elution conditions. This protein was identified by mass spectrometry method as the 78 kDa glucose-regulated protein precursor (GRP78). It belongs to the family of 70 kDa heat shock proteins, recently GRP78 was reported to be localized on the surface of different cell types, including hepatocytes. 相似文献
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Cherepanova OA Kalmykova N Petrov YP Blinova M Pinaev G 《Cell biology international》2006,30(10):784-792
Laminin-2/4 is the major laminin isoform of normal muscle and nerve tissues and plays an important role in tumor invasion and metastasis. Despite the fact that laminin-2/4 has been found in the skin basement membrane, insufficient evidence is available on the effect of laminin-2/4 on the behavior of both normal and transformed skin cells. A comparison of the contribution of alpha2beta1, alpha3beta1, alpha6beta4 integrins and 67 kDa laminin receptor on the surface of the human epidermoid carcinoma cell, A-431, to interaction with laminin-2/4 was carried out. The cell interaction with extracellular matrix component is a multistage process. We employed new methods for studying different stages of the interaction of A-431 cells with laminin-2/4. We demonstrated that integrins alpha2beta1, alpha3beta1, alpha6beta4 and 67 kDa laminin receptor are involved in the interaction of A-431 cells with laminin-2/4. We found that contribution of the same receptors to different stages of the interaction with laminin can be different. alpha2beta1 integrins are involved in EGF-induced A-431 cells' migration on laminin-2/4. We demonstrated the cooperation between alpha2beta1 and alpha3beta1 integrins during adhesion and spreading of A-431 cells on laminin-2/4-coated substrate. These results provide information about laminin-2/4 receptors and their contribution to different stages of the interaction with cells. 相似文献