ABSTRACT
A method was developed to elucidate the structures of sulfated oligosaccharides through establishment of an effective reversed phase ion pair ultra-performance liquid chromatography coupled with electrospray ionization time of flight mass spectrometry( RPIP-UPLC-ESI-TOF-MS). Heptylamine (20 mmol/L,pH4) has been selected as the ion-pairing agent.κ-Carrageenan oligosaccharides have been separated on BEH C_(18) column using MeOH/H_2O with 25% heptylammonium formate as eluent in linear gradient mode. Mass spectra were obtained by ESI-Q-TOF-MS in both positive and negative modes. κ-Carrageenan oligosaccharides were well separated up to pentatetrasaccharide,and ESIMS analysis for κ-carrageenan oligosaccharides up to hepta-cosasccharide. The results showed that all acid hydrolyzed κ-carrageenan oligosaccharides were odd sugars,which was further confirmed by polyacrylamide gel electrophoresis ( PAGE). The characteristic fragmentation pattern of ion-pair oligosaccharides in mass spectra can be applied for rapid structure identification.
ABSTRACT
BACKGROUND: NOV protein encoded by nephroblastoma overexpression gene(NOV) is IGF(insulin-like growth factor) -binding protein. What is its impact on human neural stem cell(hNSC) proliferation and differentiation?OBJECTIVE: To investigate the impacts of NOV protein on hNSCs proliferation and differentiation.DESIGN: A single factor analysis of variance experimental study using cells as subjectsSETTING: Department of histology and embryology, and department of neurobiology in a military medical university.MATERIALS: Study was conducted in the Department of Histology and Embryology of the Third Military Medical University of Chinese PLA. Subjects were hNSCs cultured from 10 to 14 weeks human embryo cerebral cortex.INTERVENTIONS: COS-7 cells were transfected by NOV gene recombined plasmid. COS-7 cell and COS-7 cell modified by NOV gene conditioned culture media(COS-CM and NOV-CM) were collected and reacted with the cultured HNSCs.MAIN OUTCOME MEASURES: hNSCs proliferation was detected by 3H-TdR scintillation analysis, and hNSCs differentiation was detected by immunocytochemistry and flow cytometer(FCM).RESULTS: Both COS-CM and NOV-CM could significant promote the intake of 3H-TdR by HNSCs, of which the 1/minute of NOV-CM group was significantly higher than that of COS-CM group(P ＜ 0.05), which indicated that NOV-CM contained component that could facilitate hNSCs proliferation, and moreover, there was certain dose-effect relationship in NOV-CM' s facilitation of cellular proliferation. The results of immunocytochemistry and FCM revealed that there were more NF-200 positive cells in NOV-CM group, while many glial fibrillary acidic protein positive cells could be seen in COS-CM group.CONCLUSION: NOV protein might have facilitative effects on hNSCs proliferation and differentiation into neurons.
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Objective To explore the effect of hypoxia on the expression of Janus kinase (JAK) in cocultured pulmonary arterial smooth muscle cells (PASMC) Methods Rat PASMC were cocultured with lung microvascular endothelial cells (LMVEC), the expression of JAK protein in PASMC was detected with Immunocytochemical method Results Expressions of JAK1 and JAK3 Protein were seen excessive positive (++++) in the cytoplasm of simple PASMC in hypoxia, and better positive (+++) in cocultured PASMC in hypoxia Compared with those of the control group, the expressions of JAK1 and JAK3 protein obviously increased in PASMC in hypoxia for 2 h, reached highest in those with hypoxia for 6 h, and decreased in those with hypoxia for 12 hours hypoxia, but still higher than those in hypoxia for 2 h Conclusion Hypoxia modulates the signal pathways and improves cell proliferation by the enhancement of the expressions of JAK1 and JAK2 proteins in co cultured PASMC
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Objective To explore a practicable method of serial sections of whole CNS in the rat, in which both neurons and nerve fibers were showed at the same section. Methods After perfused fixation and quick freezing, the tissues of whole CNS were cut into serial sections with cryostat followed by hematoxylin stain. Results The nerve fibers were stained in blue color while the neurons were showed black-blue and the background was light-yellow.Conclusion Our method was feasible to show both neurons and nerve fibers at the same section with quick freezing, freezing serial sectioning and improved hematoxylin staining.