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1.
T.D. Mashkova T.A. Akopian L.Y. Romanova S.P. Mitkevich Y.B. Yurov L.L. Kisselev I.A. Alexandrov 《Gene》1994,140(2):211-217
Two -satellite fragments specific for human chromosome 4 have been cloned and characterized. Under stringent annealing conditions, they hybridized in situ only to the pericentromeric region of chromosome 4, but under nonstringent conditions they hybridized to all chromosomes containing the sequences of -satellite suprachromosomal family 2 (viz., chromosomes 2, 4, 8, 9, 13, 14, 15, 18, 20, 21 and 22). Southern blot analysis reveals the 3.2-kb higher-order repeated unit which exists in two forms: as a single MspI fragment or a combination of the 2.6-kb and 0.6-kb MspI fragments. The two chromosome-4-specific cloned sequences appear to be different parts of this repeated unit. Taken together they constitute about 60% of its length. The primary structure of the higher-order repeated unit is characterized by a dimeric periodicity of the D1-D2 type which is usual to suprachromosomal family 2. At least in one site this regularity is disrupted by monomer deletion leading to the D2-D2 monomeric order. The most likely mechanism of this monomer excision is homologous unequal crossing-over. These sequences may serve as both cytogenetic and restriction-fragment length polymorphism (RFLP) markers for the pericentromeric region of chromosome 4. 相似文献
2.
Markéta Ondračková Maria Yu Tkachenko Veronika Bartáková Anna Bryjová Michal Janáč Grzegorz Zięba Kacper Pyrzanowski Yuriy Kvach 《Journal of fish biology》2023,102(2):426-442
In Poland, distribution of non-native pumpkinseed Lepomis gibbosus (Centrarchidae) is strictly limited to the Oder river basin, where it was introduced in the early 20th century. Recently, several populations have been found in waterbodies adjacent to the Oder, particularly in its lower reaches. In this study, we compare the genetic relatedness of populations in the Oder basin with other European populations using nuclear (microsatellite) and mitochondrial (partial cytochrome c oxidase subunit I; cox1) markers. Microsatellite analysis indicated that four populations in the lower Oder form a separate cluster, while one in the middle Oder clustered with Danubian populations, from where probably having been introduced. Microsatellite data suggested that the lower Oder populations differ from other non-native European populations, making it impossible to estimate the source of introduction. Nevertheless, analysis of cox1 indicated that Oder pumpkinseeds belong to the same haplotype as the vast majority of European populations. Parasitological examination confirmed the presence of two North American species, the monogenean Onchocleidus dispar and trematode Posthodiplostomum centrarchi, in the lower Oder, both previously unknown in the region. Fifteen other parasite species were acquired, including glochidia of invasive Sinanodonta woodiana. In the middle Oder, parasite infection was more limited. Fish from the Gryfino Canal, considered one of the most invasive populations in Europe, showed the highest parasite abundance and diversity, and the highest somatic condition and growth rate due to warm water released from the Dolna Odra power plant. Our results highlight significant differences in somatic condition and parasite infection in long-established non-native pumpkinseed populations in the same river system, reflecting mainly environmental conditions. 相似文献
3.
Evelina L Zdorovenko Evgeny Vinogradov Galina M Zdorovenko Buko Lindner Olga V Bystrova Alexander S Shashkov Klaus Rudolph Ulrich Z?hringer Yuriy A Knirel 《European journal of biochemistry》2004,271(23-24):4968-4977
The core structure of the lipopolysaccharide (LPS) isolated from a rough strain of the phytopathogenic bacterium Pseudomonas syringae pv. phaseolicola, GSPB 711, was investigated by sugar and methylation analyses, Fourier transform ion-cyclotron resonance ESI MS, and one- and two-dimensional 1H-, 13C- and 31P-NMR spectroscopy. Strong alkaline deacylation of the LPS resulted in two core-lipid A backbone undecasaccharide pentakisphosphates in the ratio approximately 2.5 : 1, which corresponded to outer core glycoforms 1 and 2 terminated with either L-rhamnose or 3-deoxy-D-manno-oct-2-ulosonic acid (Kdo), respectively. Mild acid degradation of the LPS gave the major glycoform 1 core octasaccharide and a minor truncated glycoform 2 core heptasaccharide, which resulted from the cleavage of the terminal Kdo residues. The inner core of P. syringae is distinguished by a high degree of phosphorylation of L-glycero-D-manno-heptose residues with phosphate, diphosphate and ethanolamine diphosphate groups. The glycoform 1 core is structurally similar but not identical to one of the core glycoforms of the human pathogenic bacterium Pseudomonas aeruginosa. The outer core composition and structure may be useful as a chemotaxonomic marker for the P. syringae group of bacteria, whereas a more conserved inner core structure appears to be representative for the whole genus Pseudomonas. 相似文献
4.
Beata Bartodziejska Joanna Radziejewska-Lebrecht Maria Lipinska Yuriy A. Knirel Leonid O. Kononov Anatoly Y. Chernyak Hubert Mayer Antoni Rozalski 《FEMS immunology and medical microbiology》1996,13(2):113-121
Abstract In DOC-PAGE, lipopolysaccharide (LPS) of Proteus mirabilis R14/1959 (Rb-type) mutant showed a ladder-like migration pattern indicating the presence of a high molecular weight polysaccharide chain. The isolated polysaccharide, called T-antigen because of similarity with the T1 chain of Salmonella friedenau LPS, contained d -glucose, d -galacturonic acid ( d -GalA), and d -GlcNAc in molar ratios 2:1:1 and was structurally different from the O-antigen of the parental S-strain P. mirabilis S1959 but identical to the O-antigen of another S-strain Proteus penneri 42. The importance of a d -GalA( l -Lys)-containing epitope, most likely present in the core region of LPS, and of GalA present in the T-antigen chain in manifesting the serological specificity of P. mirabilis R14/1959 were revealed using rabbit polyclonal homologous and heterologous R- and O-specific antisera and the appropriate antigens, including synthetic antigens which represent partial structures of various Proteus LPS. 相似文献
5.
Andrew M. Jackson Anton B. Alexandrov S. Prescott Keith James 《Cancer immunology, immunotherapy : CII》1995,40(2):119-124
Intravesical immunotherapy for bladder cancer is the most effective form of tumour immunotherapy. Following repeated instillations
of bacillus Calmette-Guérin (BCG) organisms into the bladder large 0quantities of several cytokines are detected in the urine.
These cytokines include interleukins IL-1β, IL-2, IL-4, IL-6, IL-8, IL-10, tumour necrosis factor α (TNFα), interferon γ (IFNγ)
and also soluble intercellular adhesion molecule ICAM-1. In the work reported here we simultaneously quantified urinary levels
of TNFα, TNFβ, TNF receptor I and TNF receptor II by enzyme-linked immunosorbent assay (ELISA) techniques and compared this
with bioactive levels of TNF. This was undertaken with a limited number of patients throughout a course of six instillations
of immuno therapy. Sequential instillations of BCG induced secretion of TNFα and TNFβ into urine. These cytokines were not
always secreted simultaneously, perhaps suggesting differential regulation of their synthesis. Maximal concentrations of TNFα
were 675 pg/ml and TNFβ 47 pg/ml. High levels of both species of soluble TNF receptor were readily identified in urine. Maximal
levels of sTNF-RI were 6200 pg/ml (range from 0) and for sTNF-RII 7800 pg/ml (range from 0). Contrasting with earlier published
observations concerning cytokine levels, the concentration of soluble receptor did not increase with repeated instillation.
In apparent contrast with the ELISA data, very low levels of bioactive TNF were identified by the L929 bioassay (maximum concentration
1 U/ml) despite the elevated concen t ration of immunoreactive TNF. The large concentrations of soluble TNF receptor in patients’
urine samples could account for the apparently low bioactivity as determined by the L929 cytotoxicity assay. The precise nature
of the role of TNF in BCG immunotherapy remains undetermined; however, it is thought that proinflammatory cytokines are in
part responsible for the clinical efficacy of this therapeutic approach. Whether other cytokines are antogonised by soluble
binding proteins remains to be determined. Furthermore, whether TNF is bioactive in the bladder wall and only neutralised
in the urine also requires investigation.
Received: 24 August 1994 / Accepted: 17 October 1994 相似文献
6.
V. V. Zverev N. P. Kuzmin L. A. Zuyeva E. I. Burova A. A. Alexandrov I. A. Khmel 《Plasmid》1984,12(3):203-205
Restriction maps have been constructed for the colicinogenic plasmids (ColA, ColD, and ColK. Their regions of homology with the ColE1 plasmid and its deletion derivative pAO3 carrying the region responsible for autonomous replication of ColE1 plasmid were determined by means of blotting hybridization and heteroduplex analysis. The plasmids ColA, ColD, and ColK were shown to contain DNA fragments homologous to the region of ColE1 involved in the regulation of replication. 相似文献
7.
N Ganchev V Serbezov E Alexandrov 《Journal of hygiene, epidemiology, microbiology, and immunology》1977,21(4):405-411
In 1973 the authors investigated the incidence of Q fever serologically by means of the reaction of complement fixation (RCF) and the method of immunofluorescent titration (MIFT) in two inadequately investigated occupational groups--communal workers from the town of Russe and medical workers in obstetric departments of several towns in North Bulgaria. In addition, they carried out comparative studies in order to characterize the incidence and the degree of affection from the same disease in other persons exposed and not exposed at work in the same area--transport workers and blood donors. Out of 198 communal workers, 91 (45.95 +/- 3.54%) had positive titres for Q fever (1:8--1:512). A high incidence of Q fever was established in dustmen (61.40%), sweepers (46.55%) and drivers of dust cars (38.00%), i.e. persons collecting and rendering harmless the garbage of big town. Out of 174 medical workers in obstetric departments 65 (37.36% +/- 3.78%) were positive in titres 1:8--1:512. A high incidence of Q fever was established in obstetricians (57.14%), midwives (38.11%) and hospital attendants (34.38%), i.e. persons providing medical care for pregnant women or women in childbirth. In both groups the occupational hazard increases with the length of service. Out of 244 transport workers 82 (33.60% +/- 3.02%) were positive for Q fever, and out of 237 blood donors 19 (8.01 +/- 2.54%) were serologically positive for Q fever. The authors suggest continued investigation of these two occupational groups. 相似文献
8.
I A Alexandrov T D Mashkova T A Akopian L I Medvedev L L Kisselev S P Mitkevich Y B Yurov 《Genomics》1991,11(1):15-23
Two types of human chromosome 18-specific alpha satellite fragments have been cloned and sequenced. They represent closely related but distinct alphoid families formed by two different types of the higher-order repeated units (1360-bp EcoRI and 1700-bp HindIII fragments) that do not alternate in the genome. The individual repeats within each family are 99% identical and interfamily homology is about 78%. Sequence analysis shows that both repeats belong to alphoid suprachromosomal family 2, but their homology is not higher than that of family members located on different chromosomes. Therefore, the two repeats shared a common origin in the recent past, although they are not the direct offspring of one ancestral sequence. Our data indicate that these two 18-specific domains have appeared as a result of two separate amplification events. Despite the high degree of homology, they are not undergoing intrachromosomal homogenization, although some variation of this process might take place within each domain. 相似文献
9.
K Alexandrov P Brookes H W King M R Osborne M H Thompson 《Chemico-biological interactions》1976,12(3-4):269-277
Administration of 3-methylcholanthrene (3MC) to rats greatly enhanced the aryl hydrocarbon hydroxylase (AHH) activity of liver nuclei. However, the binding in vitro [3H]benzo[alpha]pyrene (BP) to DNA within the nuclei which occurred at the same time as hydroxylation of BP was much less enhanced. Thin layer chromatography of the metabolites of BP produced by these nuclei revealed the same metabolites in similar relative amounts as were produced by rat liver microsomes prepared from rats which had received 3MC. The binding to DNA was further analysed by hydrolysis of the DNA and fractionation on a Sephadex column. This analysis revealed that the binding to DAN in nuclei was very similar in nature to that which occurred when calf-thymus DNA was added to microsomes metabolising BP. 相似文献
10.
Zhang Guanshi Zhang Jialing DeHoog Rachel J. Pennathur Subramaniam Anderton Christopher R. Venkatachalam Manjeri A. Alexandrov Theodore Eberlin Livia S. Sharma Kumar 《Metabolomics : Official journal of the Metabolomic Society》2020,16(1):1-12
Metabolomics - Food and dietary ingredients have significant effects on metabolism and health. To evaluate whether and how different diets affected the serum lipidomic profile of dogs. Sixteen... 相似文献