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11.
Patricia R Facciotti Rose EG Rici Durvanei A Maria Marcelo Bertolini Carlos E Ambrósio Maria A Miglino 《Reproductive biology and endocrinology : RB&E》2009,7(1):25-7
Background
Placental and fetal growth requires high rates of cellular turnover and differentiation, which contributes to conceptus development. The trophoblast has unique properties and a wide range of metabolic, endocrine and angiogenic functions, but the proliferative profile of the bovine placenta characterized by flow cytometry analysis and its role in fetal development are currently uncharacterized. Complete understanding of placental apoptotic and proliferative rates may be relevant to development, especially if related to the pathogenesis of pregnancy losses and placental abnormalities. 相似文献12.
S. N. Pleskova I. S. Golubeva Yu. K. Verevkin E. A. Pershin V. N. Burenina V. V. Korolichin 《Applied Biochemistry and Microbiology》2011,47(1):23-26
A decrease in CFU of gram-positive and gram-negative bacteria on the surface of UV illuminated TiO2 films (wavelength of 380 nm) is shown. A 29, 45, and 47% decrease in bacterial viability of Staphylococcus aureus, Staphylococcus epidermidis, and Escherichia coli, respectively, was seen after 12-min exposition. It was first discovered that the reuse of TiO2 films to test a bacterial suspension for viability removes UV-induced bactericidal activity. However, annealing of TiO2 at a temperature above 400°C restores the photoinduced bactericidal activity to its initial state. 相似文献
13.
Inhibition of a nutrient-dependent pinocytosis in dictyostelium discoideum by the amino acid analogue hadacidin 总被引:3,自引:1,他引:2 下载免费PDF全文
In the present study we examine the effects of the drug hadacidin (N-formyl-N- hydroxyglycine) on pinocytosis in the eukaryotic microorganism dictyostelium discoideum. At concentrations of up to approximately 8 mg/ml, hadacidin inhibited the rate of pinocytosis of fluorescein isothiocyanate (FITC) dextran in cells in growth medium in a concentration-dependent manner but had no effect on cells in starvation medium. Because hadacidin also inhibits cellular proliferation at this concentration, the relationship between growth rate and pinocytosis was studied further using another drug, cerulenin, to produce growth-arrest. These experiments showed no changes in the rate pinocytosis even after complete cessation of cellular proliferation. Other studies showed that the transfer of cells from growth to starvation medium reduced the rate of pinocytosis by approximately 50 percent. A reduction of similar magnitude occurred if cells were transferred from growth to starvation medium containing hadacidin. Also, no additional reduction in pinocytosis occurred when cells that had been treated with hadacidin were transferred to starvation medium containing hadacidin. These cells were able to take up [(14)C]hadacidin in the starvation medium. In contrast to the results with hadacidin-treated cells, cells in a cerulenin-induced state of growth-arrest when transferred to starvation medium exhibited the same 50 percent reduction in pinocytosis observed in cells not previously exposed to either drug. Cells treated with azide, in either growth or starvation medium, exhibited an immediate inhibition of all pinocytotic activity. After the transfer of log-phase cells to starvation medium supplemented with glucose, the reduction in rate was only approximately 10-15 percent. In contrast, a 50 percent reduction was observed after supplementation of starvation medium with sucrose, KCl, or concanavalin A. Maintaining the cells in growth medium containing hadacidin for as long as 16 h had no effect on the rate at which cells aggregated. These results are consistent with the conclusion that D. discoideum exhibits two types of pinocytotic activity: one that is nutrient dependent and the other independent of nutrients. This latter activity persists in starvation medium and is unaffected by hadacidin, whereas the nutrient-dependent activity is present in growth medium and is inhibited by hadacidin. 相似文献
14.
A N Verevkin N N Zueva V I Iakovleva E N Sokolova G P Golovkina 《Prikladnaia biokhimiia i mikrobiologiia》1988,24(1):35-41
Optimal conditions were chosen for cultivation of Escherichia coli 85 cells with a rather high fumarate-hydratase activity on a cheap medium containing no edible raw material. An active biocatalyst for the synthesis of L-malic acid from fumaric acid was obtained based on E. coli 85 cells immobilized in carrageenan. The enzymatic synthesis of L-malic acid from potassium fumarate was kinetically studied and optimized. Some thermodynamic parameters of fumaric acid hydration into malic acid were determined. A technique for assaying the reaction mixture was developed that involved high performance liquid chromatography. 相似文献
15.
16.
To estimate the EEG predictors of successful training in the voluntary control of psychomotor reactivity, 29 healthy young (aged 22.3 ± 1.5 years) musical performers were examined. The estimation was carried out in terms of segmental α-activity analysis using a biofeedback session as an example, simultaneously stimulating the EEG α rhythm and decreasing the muscle tone. On the first day of the study, the musicians followed instructions for the voluntary control of comfortable finger motor activity when performing musical passages for the right hand during a standard performance practice (without any use of an adaptive feedback). On the second day, the muscle tone and the power of the EEG α rhythm were voluntarily controlled in the context of a biofeedback technology. The analysis of the unsteady EEG segmentation showed that the dynamics of changes in the coherence and segmental characteristics of the α activity were the same for both effective biofeedback training and the standard successful performance practice: an increase in the α-rhythm coherence, an increase in the lifetime of α spindles, and a decrease in their amplitude variability. The results obtained are discussed in terms of the formation and dissociation of neuron ensembles in central mechanisms of optimal psychomotor functioning. 相似文献
17.
Jennifer J Hill Tammy-Lynn Tremblay Christiane Cantin Maureen O'Connor-McCourt John F Kelly Anne EG Lenferink 《Proteome science》2009,7(1):2-17
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18.
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
19.
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
20.
Pleskova SN Golubeva IS Verevkin IuK Pershin EA Burenina VN Korolikhin VV 《Prikladnaia biokhimiia i mikrobiologiia》2011,47(1):28-32
A decline in CFU of gram-positive and gram-negative bacteria on the surface of UV illuminated TiO2 films (wavelength of 380 nm) is shown. A 29, 45, and 47% decrease in bacterial viability of Staphylococcus aureus, Staphylococcus epidermidis, and Escherichia coli, respectively, was seen following a 12-min exposition. It was first discovered that the reuse of TiO2 films to test a bacterial suspension for viability removes UV-induced bactericidal activity. However, annealing of TiO2 at a temperature above 400 degrees C restores the photoinduced bactericidal activity to its initial state. 相似文献