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31.

Background  

TGF-β acts as an antiproliferative factor in normal epithelial cells and at early stages of oncogenesis. However, later in tumor development TGF-β can become tumor promoting through mechanisms including the induction of epithelial-to-mesenchymal transition (EMT), a process that is thought to contribute to tumor progression, invasion and metastasis. To identify EMT-related breast cancer therapeutic targets and biomarkers, we have used two proteomic approaches to find proteins that change in abundance upon the induction of EMT by TGF-β in two mouse mammary epithelial cell lines, NMuMG and BRI-JM01.  相似文献   
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33.
Two urban and two suburban biotopes of Tomsk were studied for tick-transmitted disease prevalence in ticks collected in the wild. Tick-borne encephalitis virus (TBEV), West Nile virus (WNV), Borrelia spp., Rickettsia spp., and Ehrlichia spp. were found in 6.5%, 2.2%, 8%, 2.5%, and 1.7% of tick specimens, respectively. Genetic markers of Powassan virus, Bartonella spp., and Babesia spp. were not found. Analysis of the genetic diversity of revealed pathogens demonstrated that TBEV strains belonged to the Siberian and Far-Eastern subtypes, and the Far-Eastern subtype of TBEV is most frequently found in urban biotopes (up to 43% of urban strains of TBEV). WNV strains belonged to the 1a genotype. Borrelia spp. was classified as B. garinii, Rickettsia spp. was classified as R. tarasevichiae and probably as a new Rickettsia raoultii subspecies, and Ehrlichia spp. was classified as E. muris. The coexistence of several pathogens was found in 5.7% of tick specimens, and TBEV + Borrelia spp. was the most frequent combination.  相似文献   
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35.
Two new scelionid species of the subgenus Telenomus, genus Telenomus, subfamily Telenominae are described: Telenomus (Telenomus) oculus sp. nov. and T. (T.) tetragonus sp. nov. Brief morphological characterizations of the new taxa are given, and comparative analysis of the inclusions described and members of the recent fauna is provided.  相似文献   
36.
Biological tests showed that bronchial asthma is associated with decreased contents of the endogenous sensitizer of β-adrenoreceptors (ESBAR) and the endogenous blocker of M-cholinoreceptors (EBMCR) and an increased content of the endogenous blocker of β-adrenoreceptors (EBBAR) in the blood and urine of children and adults. These phenomena are considered to be causes of bronchial asthma.  相似文献   
37.
Newborn rats were exposed to staged adaptation to altitude hypoxia in a pressure chamber at an atmospheric pressure corresponding to an altitude from 2000 to 9000 m. The time course of changes in the synthesis of RNA and DNA by the nuclei of muscle and connective tissue cells of the heart were studied by light autoradiography with the use of 3H-5-uridine and 3H-thymidine. In the course of early postnatal ontogenesis adaptation to altitude hypoxia was demonstrated to be accompanied by the intensified synthesis of nucleic acids by muscle and non-muscle cells of the heart, which is regarded as a compensatory-adaptation reaction of the myocardium to hyperfunction under the test experimental conditions.  相似文献   
38.
Peripheral alpha1,3-fucosylation of glycans occurs by the action of either one of five different alpha1,3-fucosyltransferases (Fuc-Ts) cloned to date. Fuc-TVI is one of the alpha1,3-fucosyltransferases which is capable to synthesize selectin ligands. The major alpha1, 3- fucosyltransferase activity in human plasma is encoded by the gene for fucosyltransferase VI, which presumably originates from liver cells. While the sequence, chromosomal localization, and kinetic properties of Fuc-TVI are known, immunocytochemical localization and trafficking studies have been impossible because of the lack of specific antibodies. Here we report on the development and characterization of a peptide-specific polyclonal antiserum monospecific to Fuc-TVI and an antiserum to purified soluble recombinant Fuc-TVI crossreactive with Fuc-TIII and Fuc-TV. Both antisera were applied for immunodetection in stably transfected CHO cells expressing the full-length form of this enzyme (CHO clone 61/11). Fuc-TVI was found to be a resident protein of the Golgi apparatus. In addition, more than 30% of cell-associated and released enzyme activity was found in the medium. Maturation and release of Fuc-TVI was analyzed in metabolically labeled CHO 61/11 cells followed by immunoprecipitation. Fuc-TVI occurred in two forms of 47 kDa and 43 kDa bands, while the secreted form was detected as a 43 kDa. These two different intracellular forms arose by posttranslational modification, as shown by pulse-chase experiments. Fuc-TVI was released to the supernatant by proteolytic cleavage as a partially endo-H resistant glycoform.   相似文献   
39.
Akentrogonid rhizocephalans morphologically resembling the genus Thompsonia are revised as a result of examination of new material. The species concerned are all obligatorily colonial and have ovoid or cylindrically shaped externae with a terminal stalk and a much reduced anatomy. A numerical cladistic analysis of all Rhizocephala Akentrogonida using the Hennig 86 program leads to a redefinition of the Thompsoniidae HOeg and Rybakov, 1992. Autapomorphies for the Thompsoniidae are primarily the morphology of the attachment to the host and the total absence of a mesentery. The cladistic analysis refutes that the Thompsoniidae should have a plesiomorphic morphology and branch off very low on the rhizocephalan phylogeny. The family now comprises four genera: Pottsia gen. n. (monotypic), Diplothylacus gen. n. with two species, Thompsonia Kossmann with five species. A revived and redefined Thylacoplethus Coutière includes eight species. The genera are distinguished by the location of the spermatogenic tissue, the site where the eggs are fertilized, the presence or absence of a mantle pore and the way it is formed, the number or absence of oviducts, and the number of cuticular annuli on the stalk. All 16 species, of which six are new to science, are described when necessary, and, if possible, illustrated. A phylogeny for the redefined family is proposed. Thylacoplethus is morphologically closest to the hypothetically ancestral thompsoniid and is likely paraphyletic. The new genus Polysaccus with two species, one of them new to science, and the monotypic genus Pirusaccus Lützen resemble thompsoniids in externa morphology and in being obligatorily colonial.  相似文献   
40.
Work is devoted to studying of circulation of avian flu influenza A (H5N1) virus at poultry in territory of Novosibirsk region in preepizootic period. 1901 sample from clinically healthy poultry is collected and investigated. On chicken embryos it has been isolated 28 virions, including from poultry of the industrial maintenance--16, from the poultry contained in private farmsteads--12. At the analysis of isolates it has been shown, that among poultry in preepizootic period circulated various serovars of influenza viruses namely, HI, H4 and H3 serogroups. The percent of isolates from geese of the industrial maintenance increased to 0.6% depending on area. The percent of isolates from a bird contained in private farmsteads, increased to 7.5%. The greatest percent of isolates was observed from the samples taken from hens--77. Thus, it is shown, that among poultry circulation of not pathogenic influenza viruses of type A is the usual phenomenon, and asymptomatic carriers 7.5% of a livestock. Also it has been established, that in preepizootic period 2005 (January-June) at poultry it is not revealed influenza viruses of H5 serotype, caused epizootia at Summer of 2005 in territory of Western Siberia.  相似文献   
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