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排序方式: 共有274条查询结果,搜索用时 31 毫秒
111.
Anna Jesionek Adam Kokotkiewicz Paulina Wlodarska Bozena Zabiegala Adam Bucinski Maria Luczkiewicz 《Plant Cell, Tissue and Organ Culture》2017,131(1):51-64
Rhododendron tomentosum Harmaja (Ledum palustre), a peat bog plant from Ericaceae family, has been used in traditional medicine as the anti-arthritis agent. Although modern researches confirm its anti-inflammatory properties, it remains threatened by habitat degradation and possibilities to collect this endangered species from its natural environment for further biological activity studies are limited. Therefore, R. tomentosum liquid in vitro cultures were established as the alternative source of that valuable plant material. Schenk–Hildebrandt medium with 24.60 μM 2-isopentenyladenine and 592.02 μM adenine provides intensive growth and proper morphology of the obtained microshoots. The R. tomentosum biomass was scaled up using the various bioreactors (immersion, temporary immersion and spraying systems) for better growth and improved volatile oil production. The largest biomass accumulation (fresh weight?=?250 g l?1, growth index?=?280, dry weight?=?20 g l?1) and essential oil content (0.5% v/m) were achieved with application of commercially available RITA® bioreactor. GC/MS analysis revealed the high content of p-cymene (6.9%), alloaromadendrene (5.5%), shyobunone (8.2%) and ledene oxide (II) (13.0%) in the volatile fraction obtained from RITA® system. The biomass growth parameters and production profile in terms of essential oil and selected terpenoid compounds were determined during the 2 month period. The influence of culture conditions and bioreactor construction on the growth and volatile oil production in R. tomentosum biomasses was discussed. 相似文献
112.
Zhernakova A Stahl EA Trynka G Raychaudhuri S Festen EA Franke L Westra HJ Fehrmann RS Kurreeman FA Thomson B Gupta N Romanos J McManus R Ryan AW Turner G Brouwer E Posthumus MD Remmers EF Tucci F Toes R Grandone E Mazzilli MC Rybak A Cukrowska B Coenen MJ Radstake TR van Riel PL Li Y de Bakker PI Gregersen PK Worthington J Siminovitch KA Klareskog L Huizinga TW Wijmenga C Plenge RM 《PLoS genetics》2011,7(2):e1002004
113.
114.
Hartwig W Werner J Warshaw AL Antoniu B Castillo CF Gebhard MM Uhl W Büchler MW 《American journal of physiology. Gastrointestinal and liver physiology》2004,287(6):G1194-G1199
In acute pancreatitis, ICAM-1 is upregulated in various organs and contributes to the development of organ injury. To investigate the effects of pancreatic proteases on ICAM-1 expression and their role in the early process of leukocyte migration, human umbilical vein endothelial cells (HUVECs) were incubated with serum subjected to limited trypsin digestion and Wistar rats were injected with trypsin. Significant upregulation of membrane-bound ICAM-1 was seen on HUVECs incubated with trypsinated serum. Likewise, soluble ICAM-1 increased in the supernatant of HUVECs. Changes of membrane-bound ICAM-1 and soluble ICAM-1 were maximal with high concentrations of trypsin. HUVECs incubated with TNF-alpha (positive control) showed similar changes. In the pancreas and lungs of animals infused with trypsin, ICAM-1 and leukocyte sequestration were increased compared with controls. Reflecting the relevance of protease-induced ICAM-1 expression in leukocyte migration, leukocyte-endothelium interaction, as assessed by intravital microscopy, was markedly increased by trypsin. Inhibition of ICAM-1 ameliorated these changes significantly. In conclusion, trypsinated serum induces the upregulation of both membrane-bound ICAM-1 on endothelial cells and soluble ICAM-1. These changes contribute to the early steps of leukocyte migration in acute pancreatitis. The role of soluble ICAM-1 remains to be investigated. 相似文献
115.
Anthony D. Radice Bozena Bugaj David H. A. Fitch Scott W. Emmons 《Molecular & general genetics : MGG》1994,244(6):606-612
We characterized five transposable elements from fish: one from zebrafish (Brachydanio rerio), one from rainbow trout (Salmo gairdneri), and three from Atlantic salmon (Salmo salar). All are closely similar in structure to the Tel transposon of the nematode Caenorhabditis elegans. A comparison of 17 Tc1-like transposons from species representing three phyla (nematodes, arthropods, and chordates) showed that these elements make up a highly conserved transposon family. Most are close to 1.7 kb in length, have inverted terminal repeats, have conserved terminal nucleotides, and each contains a single gene encoding similar poly peptides. The phylogenetic relationships of the transposons were reconstructed from the amino acid sequences of the conceptual proteins and from DNA sequences. The elements are highly diverged and have evidently inhabited the genomes of these diverse species for a long time. To account for the data, it is not necessary to invoke recent horizontal transmission. 相似文献
116.
Do Han Kim Frank A. Sreter S.Tsuyoshi Ohnishi John F. Ryan James Roberts Paul D. Allen Laszlo G. Meszaros Bozena Antoniu Noriaki Ikemoto 《生物化学与生物物理学报:生物膜》1984,775(3):320-327
The time-course of Ca2+ release from sarcoplasmic reticulum isolated from muscles of normal pigs and those of pigs susceptible to malignant hyperthermia were investigated using stopped-flow spectrophotometry and arsenazo III as a Ca2+ indicator. Several methods were used to trigger Ca2+ release: (a) addition of halothane (e.g., 0.2 mM); (b) an increase of extravesicular Ca2+ concentration ([Ca02+]); (c) a combination of (a) and (b), and (d) replacement of ions (potassium gluconate with choline chloride) to produce membrane depolarization. The initial rates of Ca2+ release induced by either halothane or Ca2+ alone, or both, are at least 70% higher in malignant hyperthermic sarcoplasmic reticulum than in normal. The amount of Ca2+ released by halothane at low [Ca02+] in malignant hyperthermic sarcoplasmic reticulum is about twice as large as in normal sarcoplasmic reticulum. Membrane depolarization led to biphasic Ca2+ release in both malignant hyperthermic and normal sarcoplasmic reticulum, the rate constant of the rapid phase of Ca2+ release induced by membrane depolarization being significantly higher in malignant hyperthermic sarcoplasmic reticulum () than in normal (). Thus, all types of Ca2+ release investigated (a, b, c and d) have higher rates in malignant hyperthermic sarcoplasmic reticulum than normal sarcoplasmic reticulum. These results suggest that the putative Ca2+ release channels located in the sarcoplasmic reticulum are altered in malignant hyperthermic sarcoplasmic reticulum. 相似文献
117.
Natalia Zeber-Lubecka Maria Kulecka Filip Ambrozkiewicz Agnieszka Paziewska Milosz Lechowicz Ewa Konopka Urszula Majewska Maria Borszewska-Kornacka Michal Mikula Bozena Cukrowska Jerzy Ostrowski 《PloS one》2016,11(2)
Background
Recent advances in culture-independent approaches have enabled insights into the diversity, complexity, and individual variability of gut microbial communities.Objectives
To examine the effect of oral administration of Saccharomyces (S.) boulardii and mode of delivery on the intestinal microbial community in preterm infants.Study Design
Stool samples were collected from preterm newborns randomly divided into two groups: a probiotic-receiving group (n = 18) or a placebo group (n = 21). Samples were collected before probiotic intake (day 0), and after 2 and 6 weeks of supplementation. The composition of colonizing bacteria was assessed by 16S ribosomal RNA (rRNA) gene sequencing of fecal samples using the Ion 16S Metagenomics Kit and the Ion Torrent Personal Genome Machine platform.Results
A total of 11932257 reads were generated, and were clustered into 459, 187, and 176 operational taxonomic units at 0 days, 2 weeks, and 6 weeks, respectively. Of the 17 identified phyla, Firmicutes Actinobacteria, Proteobacteria, and Bacteroidetes were universal. The microbial community differed at day 0 compared with at 2 weeks and 6 weeks. There was a tendency for increased bacterial diversity at 2 weeks and 6 weeks compared with day 0, and infants with a gestational age of 31 weeks or higher presented increased bacterial diversity prior to S. boulardii administration. Firmicutes and Proteobacteria remained stable during the observation period, whereas Actinobacteria and Bacteroidetes increased in abundance, the latter particularly more sharply in vaginally delivered infants.Conclusion
While the mode of delivery may influence the development of a microbial community, this study had not enough power to detect statistical differences between cohorts supplemented with probiotics, and in a consequence, to speculate on S. boulardii effect on gut microbiome composition in preterm newborns. 相似文献118.
Sylwia Kedracka-Krok Urszula Jankowska Martyna Elas Urszula Sowa Jan Swakon Agnieszka Cierniak Pawel Olko Bozena Romanowska-Dixon Krystyna Urbanska 《PloS one》2014,9(1)
Proton beam irradiation is a form of advanced radiotherapy providing superior distributions of a low LET radiation dose relative to that of photon therapy for the treatment of cancer. Even though this clinical treatment has been developing for several decades, the proton radiobiology critical to the optimization of proton radiotherapy is far from being understood. Proteomic changes were analyzed in human melanoma cells treated with a sublethal dose (3 Gy) of proton beam irradiation. The results were compared with untreated cells. Two-dimensional electrophoresis was performed with mass spectrometry to identify the proteins. At the dose of 3 Gy a minimal slowdown in proliferation rate was seen, as well as some DNA damage. After allowing time for damage repair, the proteomic analysis was performed. In total 17 protein levels were found to significantly (more than 1.5 times) change: 4 downregulated and 13 upregulated. Functionally, they represent four categories: (i) DNA repair and RNA regulation (VCP, MVP, STRAP, FAB-2, Lamine A/C, GAPDH), (ii) cell survival and stress response (STRAP, MCM7, Annexin 7, MVP, Caprin-1, PDCD6, VCP, HSP70), (iii) cell metabolism (TIM, GAPDH, VCP), and (iv) cytoskeleton and motility (Moesin, Actinin 4, FAB-2, Vimentin, Annexin 7, Lamine A/C, Lamine B). A substantial decrease (2.3 x) was seen in the level of vimentin, a marker of epithelial to mesenchymal transition and the metastatic properties of melanoma. 相似文献
119.
The study investigated the formulation effects of laurocapram and iminosulfurane derived penetration modifiers on human stratum
corneum using thermal and spectral analyses. Firstly, formulations of penetration modifiers were assessed as enhancers/retardants
using the model permeant, diethyl-m-toluamide followed by investigation of their mechanisms of action using differential scanning calorimetry (DSC) and attenuated
total reflectance Fourier-transform infra-red spectroscopy. The penetration modifiers investigated were laurocapram, 3-dodecanoyloxazolidin-2-one
(N-0915), S,S-dimethyl-N-(4-bromobenzoyl) iminosulfurane (DMBIS), S,S-dimethyl-N-(2-methoxycarbonylbenzenesulfonyl) iminosulfurane (DMMCBI) and tert-butyl 1-dodecyl-2-oxoazepan-3-yl-carbamate (TBDOC) that were formulated in either water, propylene glycol (PG), ethanol or
polyethylene glycol 400 (PEG 400). The results explain the mechanism for the first time why an enhancer can become a retardant
or vice versa depending upon the vehicle in which it is applied to the skin. DSC indicated that penetration modifier formulations enhanced
permeation of active mainly by disruption and fluidization of the stratum corneum lipid bilayers while IR data indicated characteristic
blue shifts with decreases in peak intensity. On the other hand, DSC of penetration modifier formulations showing retardation
depicted elevated T
m2 with a strengthening of lipid–protein complex while IR results indicated formation of multiple peaks around 1,738 cm−1 transition in stratum corneum spectra suggesting retardation may be caused by organization of SC lipids by increased H-bonding. 相似文献
120.
It is now generally accepted that non‐genomic steroids action precedes their genomic effects by modulation of intracellular signaling pathways within seconds after application. Ca2+ is a very potent and ubiquitous ion in all cells, and its concentration is precisely regulated. The most sensitive on Ca2+ increase is ATP‐consuming plasma membrane calcium pump (PMCA). The enzyme is coded by four genes, but isoforms diversity was detected in excitable and non‐excitable cells. It is the only ion pump stimulated directly by calmodulin (CaM). We examined the role of PMCA isoforms composition and CaM effect in regulation of Ca2+ uptake by estradiol, dehydroepiandrosterone (DHEA), pregnenolone (PREG), and their sulfates in a concentration range from 10?9 to 10?6 M, using the membranes from rat cortical synaptosomes, differentiated PC12 cells, and human erythrocytes. In excitable membranes with full set of PMCAs steroids apparently increased Ca2+ uptake, although to a variable extent. In most of the cases, CaM decreased transport by 30–40% below controls. Erythrocyte PMCA was regulated by the steroids somewhat differently than excitable cells. CaM strongly increased the potency for Ca2+ extrusion in membranes incubated with 17‐β‐estradiol and PREG. Our results indicated that steroids may sufficiently control cytoplasmic calcium concentration within physiological and therapeutic range. The response depended on the cell type, PMCA isoforms expression profile, CaM presence, and the steroids structure. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献