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991.
E. A. Anedchenko A. A. Dmitriev G. S. Krasnov O. O. Kondrat’eva E. P. Kopantsev T. V. Vinogradova M. V. Zinov’eva I. B. Zborovskaya B. E. Polotsky O. V. Sacharova V. I. Kashuba E. R. Zabarovsky V. N. Senchenko 《Molecular Biology》2008,42(6):859-869
Chromosomal and genome abnormalities of 3p are frequent in many epithelial tumors, including lung cancer. Several critical regions with a high frequency of hemi-and homozygous deletions in tumors are known for 3p, and more than 20 cancer-related genes occur in 3p21.3. Quantitative real-time PCR was used to measure the mRNA level for tumor-suppressor and candidate genes of 3p21.3 (RBSP3/CTDSPL, NPRL2/G21, RASSF1A, ITGA9, HYAL1, and HYAL2) in major types of non-small cell lung cancer (NSCLC): squamous cell lung cancer (SCC) and lung adenocarcinoma (AC). A significant (2-to 100-fold) and frequent (44–100%) decrease in mRNA levels was observed in NSCLC. The mRNA level decrease and its frequency depended on the histological type of NSCLC for all genes. The downregulation of RASSF1A and ITGA9 was significantly associated with AC progression; the same tendency was observed for RBSP3/CTDSPL, NPRL2/G21, HYAL1, and HYAL2. In SCC, the downregulation of all genes was not associated with the clinical stage, tumor cells differentiation, and metastasis in lymph nodes. The RBSP3/CTDSPL, NPRL2/G21, ITGA9, HYAL1, and HYAL2 mRNA levels significantly (5-to 13-fold on average) decreased at a high frequency (83–100%) as early as SCC stage I. Simultaneous downregulation of all six genes was observed in some tumor samples and was independent of the gene position in 3p21.3 and the functions of the protein products. The Spearman correlation coefficient r s was 0.63–0.91, p < 0.001. The highest r s values were obtained for gene pairs ITGA9-HYAL2 and HYAL1-HYAL2, whose products mediate cell-cell adhesion and cell-matrix interactions; coregulation of the genes was assumed on this basis. Both genetic and epigenetic mechanisms proved to be important for downregulation of RBSP3/CTDSPL and ITGA9. This finding supported the hypothesis that the cluster of cancerrelated genes in the extended 3p21.3 locus is simultaneously inactivated during the development and progression of lung cancer and other epithelial tumors. A significant and frequent decrease in the mRNA level of the six genes in SCC could be important for developing specific biomarker sets for early SCC diagnosis and new approaches to gene therapy of NSCLC. 相似文献
992.
Yu. A. Nikolaev V. K. Plakunov N. A. Voronina N. V. Nemtseva A. O. Plotnikov O. A. Gogoleva M. E. Murav’eva G. V. Ovechkina 《Microbiology》2008,77(1):78-83
The growth characteristics of an algo-bacterial community (Chlamydomonas reinhardtii and bacterial satellites) were studied, as well as the mechanism and patterns of bacterial effect on algae. Four strains of predominant bacteria were isolated and partially characterized. They were assigned to the following taxa: Rhodococcus terrea, Micrococcus roseus, and Bacillus spp. A pure culture of the alga under study was obtained by plating serial dilutions on agarized media. Within the algo-bacterial association, the alga had a higher growth rate (0.76 day?1) and yield (60 μg chlorophyll/ml culture) than in pure cultures (0.4 day?1 and 10 μg chlorophyll/ml culture, respectively). The viability of the algal cells within the association was retained longer than in pure culture. Among the isolated bacterial satellites, strains B1 and Y1, assigned to the species Rhodococcus terrae, had the highest stimulatory effect on algal growth. The culture liquid of bacteria incubated under the conditions not permitting growth stimulated algal growth; the culture liquid of actively growing bacteria had an opposite effect. 相似文献
993.
M. V. Nemtsova E. M. Paltseva A. Yu. Babayan D. S. Mihaylenko O. V. Babenko O. Yu. Samofalova P. V. Tsar’kov D. V. Zaletaev 《Molecular Biology》2008,42(6):925-931
Molecular genetic analysis of allelic deletions from the loci containing the tumor suppressor genes p16, p15, p19 (9p21), RB1 (13p14), PTEN (10q23), and TP53 (17p13); microsatellite instability; and activating mutations of K-RAS (codons 12 and 13) was performed in four different segments of sporadic colorectal cancer (CRC) in 11 patients. Intratumoral genetic heterogenity was detected in 9 out of 11 (81%) colorectal adenocarcinomas and was morphologically validated. Analysis of different segments of one tumor reported that not only intratumoral heterogeneity, but also the order of the appearance and distribution of molecular anomalies during tumorigenesis in sporadic CRC. K-RAS point mutations and anomalies of the p16-RB1-cyclin D pathway were assumed to occur prior to microsatellite instability and PTEN deletions during tumor progression. 相似文献
994.
995.
Predator diversity enhances secondary production and decreases the likelihood of trophic cascades 总被引:1,自引:0,他引:1
We manipulated the diversity of top predators in a three trophic level marine food web. The food web included four top benthic
marine fish predators (black goby, rock goby, sea scorpion and shore rockling), an intermediate trophic level of small fish,
and a lower trophic level of benthic invertebrates. We kept predator density constant and monitored the response of the lower
trophic levels. As top predator diversity increased, secondary production increased. We also observed that in the presence
of the manipulated fish predators, the density of small gobiid fish (intermediate consumers) was suppressed, releasing certain
groups of benthic invertebrates (caprellid amphipods, copepods, nematodes and spirorbid worms) from heavy intermediate predation
pressure. We attribute the mechanism responsible for this trophic cascade to a trait-mediated indirect interaction, with the
small gobiid fish changing their use of space in response to altered predator diversity. In the absence of top fish predators,
a full-blown trophic cascade occurs. Therefore the diversity of predators reduces the likelihood of trophic cascades occurring
and hence provides insurance against the loss of an important ecosystem function (i.e. secondary production). 相似文献
996.
Optimization of in vitro tuberization (formation and growth of stolons and microtubers) by synchronization of cell divisions in axillary meristems of initial stem explants induced by low nonfreezing temperatures was studied in potato (Solanum tuberosum L., cv. Lugovskoi) plants. The proportion of simultaneously dividing cells in axillary meristems of stem explants subjected to 2-h cold treatment at 4°C was in 2.6 times greater than in control material (without chilling). The analysis of growth of stolons and microtubers produced from the explants exposed to cold showed that synchronization of cell divisions in the meristems of initial explants resulted in synchronization of stolon and microtuber formation and production of microtubers of identical physiological age. 相似文献
997.
O'Neill CM Morgan C Kirby J Tschoep H Deng PX Brennan M Rosas U Fraser F Hall C Gill S Bancroft I 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2008,116(5):623-634
Quantitative approaches are now widely used to study the genetic architecture of complex traits. However, most studies have
been conducted in single mapping populations, which sample only a fraction of the natural allelic variation available within
a gene pool and can identify only a subset of the loci controlling the traits. To enable the progress towards an understanding
of the global genetic architecture of a broad range of complex traits, we have developed and characterised six new Arabidopsis thaliana recombinant inbred populations. To evaluate the utility of these populations for integrating analyses from multiple populations,
we identified quantitative trait loci (QTL) controlling flowering time in vernalized plants growing in 16 h days. We used
the physical positions of markers to align the linkage maps of our populations with those of six existing populations. We
identified seven QTL in genomic locations coinciding with those identified in previous studies and in addition a further eight
QTL were identified.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
An erratum to this article can be found at 相似文献
998.
Effect of cold stimulation of the arm fingers on the spectral/coherent EEG characteristics in humans
V. V. Garkavenko O. P. Man’kovskaya T. G. Omel’chenko A. V. Gorkovenko A. N. Shevko 《Neurophysiology》2008,40(3):228-230
Examination of modifications of EEG in humans induced by cold stimulation of the arm fingers showed that the EEG frequency
composition noticeably depended on this thermal influence (in the relaxed state with no movements or during realization of
voluntary cyclic movements by the fingers of another arm). In the resting state, cold stimulation mostly induced intensification
of the delta activity, while, when coinciding with the performance of voluntary movements, it also resulted in increases in
the powers of oscillations of the alpha1 and beta1 ranges. The structure of changes in the coefficients of coherence under
the influence of cooling also depended on the conditions of testing (in the resting state or during motor activity). Therefore,
the effect of tonic cold stimulation on the interaction between synchronizing and desynchronizing cerebral systems and interrelations
between different cortical zones was modified under conditions of realization of a motor function.
Neirofiziologiya/Neurophysiology, Vol. 40, No. 3, pp. 268–270, May–June, 2008. 相似文献
999.
Cormican P Meade KG Cahalane S Narciandi F Chapwanya A Lloyd AT O'Farrelly C 《Immunogenetics》2008,60(3-4):147-156
The anti-microbial peptides β-defensins constitute a large family of innate immune effector molecules, conserved across a
wide species range. In this paper, we describe a systematic search of the sequenced bovine genome to characterise this extensive
gene family in Bos taurus, providing an insight into the pattern of conservation of β-defensin genes between species. We have sequenced a sub-set of
these newly discovered bovine β-defensin genes and also report expression data for these genes across a range of tissues.
We have synthesised the peptide product of one of these genes, bovine β-defensin 123, and found it to be a potent inhibitor
of several pathogenic microbes, particularly Escherichia coli and Listeria monocytogenes.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
1000.
V. I. Emel’yanov Zh. N. Kravchuk S. A. Polyakovskii A. P. Dmitriev 《Cytology and Genetics》2008,42(2):90-95
The dynamics of induced accumulation of callose in tomato cells is studied. Localization of callose in the cells is studied by methods of fluorescence microscopy and the time needed for quantitative determination of callosa is optimized. The quantity of callose in tomato cells treated with different biotic elicitors is established. A nonlinear dependence of the deposition of callose on the concentration of chitin oligomers containing 3–5 fragments of N-acetylglucosamine is established and a proportional increase in the content of callose in the cells with increasing concentration of chitin dimer and chitosan in the culture medium is demonstrated. 相似文献