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991.
Bc1-2 protein was analysed in cell cultures derived from non-Hodgkin lymphomas and chronic lymphocytic leukaemia patients. The presence of bc1-2 proto-oncogene protein product has been demonstrated on cytospin preparations utilising immunochemical methods. The correlation between the expression of the bc1-2 protein and the appearance of proliferation- or differentiation related figures was studied. The reported bc1-2 up regulation in malignant lymphoid cells was confirmed in haemo- and lymphopoietic progenitor cells as well as in TPA/PHA activated peripheral blood lymphocytes. In comparison to neoplastic cells lower intensity of bc1-2 positive staining in freshly isolated cells from non-leukaemic tissue was observed. 相似文献
992.
Induced expression of PD-1, a novel member of the immunoglobulin gene superfamily, upon programmed cell death. 总被引:48,自引:0,他引:48 下载免费PDF全文
The classical type of programmed cell death is characterized by its dependence on de novo RNA and protein synthesis and morphological features of apoptosis. We confirmed that stimulated 2B4.11 (a murine T-cell hybridoma) and interleukin-3 (IL-3)-deprived LyD9 (a murine haematopoietic progenitor cell line) died by the classical type of programmed cell death. Assuming that common biochemical pathways might be involved in the deaths of 2B4.11 and LyD9, we isolated the PD-1 gene, a novel member of the immunoglobulin gene superfamily, by using subtractive hybridization technique. The predicted PD-1 protein has a variant form of the consensus sequence found in cytoplasmic tails of signal transducing polypeptides associated with immune recognition receptors. The PD-1 gene was activated in both stimulated 2B4.11 and IL-3-deprived LyD9 cells, but not in other death-induced cell lines that did not show the characteristic features of the classical programmed cell death. Expression of the PD-1 mRNA in mouse was restricted to the thymus and increased when thymocyte death was augmented by in vivo injection of anti-CD3 antibody. These results suggest that activation of the PD-1 gene may be involved in the classical type of programmed cell death. 相似文献
993.
Akihiro?KakezawaEmail authorView authors OrcID profile Minoru?N.?Tamura Kiyokazu?Agata Wataru?Shinohara 《Plant Systematics and Evolution》2017,303(6):807-813
A high-mountain dwarf plant of Lysimachia japonica (Primulaceae) endemic to Yakushima is reported to be very unique in the dwarfing mechanism at cell level, and the plant is one of the candidates to be a key species to reveal the unsolved molecular mechanism of taxon-specific body size of plant. In the present study, we examined the crossability between the dwarf plant of L. japonica and its normal-sized lowland counterpart, and self- and cross-compatibilities within each linage. The results indicate that both dwarfed and normal-sized L. japonica are self- and cross-compatible within each ecotype and are bidirectionally cross-compatible with each other, suggesting that this plant possesses optimum life historical traits for further genetic analysis in order to clarify the mystery of molecular mechanism of taxon-specific body size. 相似文献
994.
Rosalia Pellitteri Roberta Bonfanti Michela Spatuzza Maria Teresa Cambria Mariacristina Ferrara Giuseppina Raciti Agata Campisi 《Molecular neurobiology》2017,54(9):6785-6794
Herein, we assessed in a particular glial cell type, called olfactory ensheathing cells (OECs), the effect of some growth factors (GFs) on tissue transglutaminase (TG2) overexpression induced by amyloid-beta (Aβ) with native full-length peptide 1–42 or by fragments, 25–35 or 35–25, as control. Previously, we demonstrated that TG2 overexpression induced by some stressors was down-regulated by GFs exposure in OECs. To monitor cell viability, an MTT test was used, while TG2 expression was examined using immunocytochemical and Western blot analysis. We also considered the involvement of the TG2-mediated apoptotic pathway. Vimentin expression was evaluated as well. Reactive oxygen species and reduced glutathione levels were utilized to test the oxidative intracellular status. Lactate dehydrogenase released into the medium, as a marker of necrotic cell death, was evaluated. We found that in OECs exposed to Aβ(1–42) or Aβ(25–35) for 24 h, TG2 expression increased, and we observed that the protein appeared prevalently localized in the cytosol. The pre-treatment with GFs, basic fibroblast growth factor (bFGF) or glial-derived neurotrophic factor (GDNF), down-regulated the TG2 level, which was prevalently limited to the nuclear compartment. Vimentin expression and caspase cleavage showed a significant enhancement in Aβ(1–42) and Aβ(25–35) exposed cells. The pre-treatment with bFGF or GDNF was able to restore the levels of the proteins to control values, and the intracellular oxidative status modified by the exposure to Aβ(1–42) or Aβ(25–35). Our data suggest that both bFGF or GDNF could be an innovative mechanism to contrast TG2 expression, which plays a key role in Alzheimer’s disease. 相似文献
995.
A versatile genetic toolbox for Prevotella copri enables studying polysaccharide utilization systems
Jing Li Eric J C Glvez Lena Amend va Almsi Aida Iljazovic Till R Lesker Agata A Bielecka EvaMagdalena Schorr Till Strowig 《The EMBO journal》2021,40(23)
Prevotella copri is a prevalent inhabitant of the human gut and has been associated with plant‐rich diet consumption and diverse health states. The underlying genetic basis of these associations remains enigmatic due to the lack of genetic tools. Here, we developed a novel versatile genetic toolbox for rapid and efficient genetic insertion and allelic exchange applicable to P. copri strains from multiple clades. Enabled by the genetic platform, we systematically investigated the specificity of polysaccharide utilization loci (PULs) and identified four highly conserved PULs for utilizing arabinan, pectic galactan, arabinoxylan, and inulin, respectively. Further genetic and functional analysis of arabinan utilization systems illustrate that P. copri has evolved two distinct types of arabinan‐processing PULs (PULAra) and that the type‐II PULAra is significantly enriched in individuals consuming a vegan diet compared to other diets. In summary, this genetic toolbox will enable functional genetic studies for P. copri in future. 相似文献
996.
Optimal habitat conditions for the globally threatened Aquatic Warbler Acrocephalus paludicola in eastern Poland and their implications for fen management 下载免费PDF全文
Janusz Kloskowski Franziska Tanneberger Piotr Marczakiewicz Anna Wiśniewska Agata Choynowska 《Ibis》2015,157(2):406-412
To identify optimal habitat for the Aquatic Warbler Acrocephalus paludicola, a flagship species of fen mires, we related numbers of singing males to habitat variables in all core breeding sites in eastern Poland. The density of male Aquatic Warblers increased with increasing ground cover by water and mosses and litter layer height, and was highest where vegetation was 60–90 cm tall. Male densities also increased with the biomass of arthropods > 10 mm length, estimated by sweep netting, and with the abundance of spiders, estimated by pan trapping. We suggest that habitat management should take into account species‐specific morphological adaptations, nest safety and arthropod productivity. Prevention of vegetation succession is a conservation priority for open fen mires. However, modern management practices to achieve this, especially mowing using tracked vehicles, should be evaluated and optimized to ensure that such practices do not adversely affect the long‐term development of moss cover and litter structure. 相似文献
997.
998.
Zieniuk Bartłomiej Fabiszewska Agata Białecka-Florjańczyk Ewa 《Bioprocess and biosystems engineering》2020,43(4):605-613
Bioprocess and Biosystems Engineering - Lipases are a group of enzymes of considerable significance in organic synthesis, among which Candida antarctica lipase B (CALB) is one of the most widely... 相似文献
999.
Malgorzata Duda Malgorzata Grzesiak Malgorzata Knet Katarzyna Knapczyk-Stwora Zbigniew Tabarowski Agata Michna Maria Slomczynska 《Molecular biology reports》2014,41(7):4213-4222
We used our model system for agonism and antagonism of the androgen receptor (AR), in which the porcine ovarian follicles were exposed on the excessive concentration of an AR agonist- testosterone (T) or an AR antagonist- 2-hydroxyflutamide (2-Hf) to: (1) analyze the spatiotemporal expression of ovarian 3β-hydroxysteroid dehydrogenase (3β-HSD), cytochrome P450 17α-hydroxylase/c17,20-lyase (P450c17) and cytochrome P450 aromatase (P450arom); (2) to determine the contribution of AR-mediated action during steroidogenesis and (3) to establish some correlations between the onset and expression pattern of the investigated proteins. Whole follicles (6–8 mm in diameter) isolated from mature porcine ovaries have been incubated (for 24 h) in an organ culture system in the presence of T (10?7 M), 2-Hf (1.7 × 10?4 M) or both T and 2-hydroxyflutamide (T+2-Hf, at the same concentrations as when added separately). Thereafter, sections obtained from cultured follicles were processed for main steroidogenic enzymes detection by immunohistochemistry. Moreover, expression of their mRNA and protein was determined by real-time PCR and Western blot analysis. Progesterone, androgens and estradiol concentrations in the culture media were measured by radioimmunoassays (RIA). Our results demonstrated that 2-Hf can influence the steroidogenic activity of porcine follicles in vitro through the blockade of AR. It was shown that follicular 2-Hf treatment brought about dramatic decline in the production of the investigated steroids. What is more the addition of 2-Hf separately caused a negative effect on 3β-HSD and P450c17 mRNA and protein expression by ovarian follicles, while it was without effect on P450arom mRNA level. Quite opposite effect was observed in case of the simultaneous addition of 2-Hf and T. It caused high increase, in both P450arom mRNA and its protein. What was interesting, addition T+2-Hf evoked 3β-HSD and P450c17 increase on mRNA level, but decreased their protein expression. This was against our expectations but the reason for that finding remains undiscovered, intriguing and worth reporting. These results suggest that alike, steroidogenic enzymes activity and their expression is associated with the presence of androgens and AR in the porcine ovary. 相似文献
1000.
A V Gurkovskaia N I Gokina V A Bury? M F Shuba 《Biulleten' eksperimental'no? biologii i meditsiny》1987,103(1):68-71
Cavinton at a concentration of 10(-7)-10(-5) M was found to have a dose-dependent relaxing effect on bovine cerebral artery smooth muscles, without changing the resting potential and membrane resistance. Smooth muscles of the rabbit portal vein and guinea-pig taenia coli were insensitive to low cavinton concentrations. The results are consistent with the hypothesis that relaxing action of cavinton is due to the blocking of Ca2+ ions influx into the cells of cerebral artery through receptor-operated calcium channels. At higher concentrations (exceeding 10(-5) M) cavinton exerts nonspecific influence on the smooth muscles under study, inhibiting their excitability and decreasing membrane resistance resulting in the attenuation of tetanic contractions in the smooth muscles of the portal vein and taenia coli. 相似文献