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21.
We describe a novel 3D fibrin matrix model using recombinant hematopoietic stem cell cytokines under serum-free defined conditions which promotes the assembly of human endothelial cell (EC) tubes with co-associated pericytes. Individual ECs and pericytes are randomly mixed together and EC tubes form that is accompanied by pericyte recruitment to the EC tube abluminal surface over a 3-5 day period. These morphogenic processes are stimulated by a combination of the hematopoietic stem cell cytokines, stem cell factor, interleukin-3, stromal derived factor-1α, and Flt-3 ligand which are added in conjunction with fibroblast growth factor (FGF)-2 into the fibrin matrix. In contrast, this tube morphogenic response does not occur under serum-free defined conditions when VEGF and FGF-2 are added together in the fibrin matrices. We recently demonstrated that VEGF and FGF-2 are able to prime EC tube morphogenic responses (i.e. added overnight prior to the morphogenic assay) to hematopoietic stem cell cytokines in collagen matrices and, interestingly, they also prime EC tube morphogenesis in 3D fibrin matrices. EC-pericyte interactions in 3D fibrin matrices leads to marked vascular basement membrane assembly as demonstrated using immunofluorescence and transmission electron microscopy. Furthermore, we show that hematopoietic stem cell cytokines and pericytes stimulate EC sprouting in fibrin matrices in a manner dependent on the α5β1 integrin. This novel co-culture system, under serum-free defined conditions, allows for a molecular analysis of EC tube assembly, pericyte recruitment and maturation events in a critical ECM environment (i.e. fibrin matrices) that regulates angiogenic events in postnatal life. 相似文献
22.
Jesu Arockiaraj Annie J. Gnanam Dhanaraj Muthukrishnan Muthukumaresan Kuppusamy Thirumalai Mukesh Pasupuleti James Milton Marimuthu Kasi 《Microbiological research》2013,168(9):569-579
Cathepsin L (MrCathL) was identified from a constructed cDNA library of freshwater prawn Macrobrachium rosenbergii. MrCathL full-length cDNA is 1161 base pairs (bp) with an ORF of 1026 bp which encodes a polypeptide of 342 amino acid (aa) long. The eukaryotic cysteine proteases, histidine and asparagine active site residues were identified in the aa sequence of MrCathL at 143–154, 286–296 and 304–323, respectively. The pair wise clustalW analysis of MrCathL showed the highest similarity (97%) with the homologous cathepsin L from Macrobrachium nipponense and the lowest similarity (70%) from human. Phylogenetic analysis revealed two distinct clusters of the invertebrates and vertebrates cathepsin L in the phylogenetic tree. MrCathL and cathepsin L from M. nipponense were clustered together, formed a sister group to cathepsin L of Penaeus monodon, and finally clustered to Lepeophtheirus salmonis. High level of (P < 0.05) MrCathL gene expression was noticed in haemocyte and lowest in eyestalk. Furthermore, the MrCathL gene expression in M. rosenbergii was up-regulated in haemocyte by virus [M. rosenbergii nodovirus (MrNV) and white spot syndrome baculovirus (WSBV)] and bacteria (Vibrio harveyi and Aeromonas hydrophila). The recombinant MrCathL exhibited a wide range of activity in various pH between 3 and 10 and highest at pH 7.5. Cysteine proteinase (stefin A, stefin B and antipain) showed significant influence (100%) on recombinant MrCathL enzyme activity. The relative activity and residual activity of recombinant MrCathL against various metal ions or salts and detergent tested at different concentrations. These results indicated that the metal ions, salts and detergent had an influence on the proteinase activity of recombinant MrCathL. Conclusively, the results of this study imply that MrCathL has high pH stability and is fascinating object for further research on the function of cathepsin L in prawn innate immune system. 相似文献
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Félix-Faure Jim Gaillard Jérémie Descloux Stéphane Chanudet Vincent Poirel Alain Baudoin Jean-Marc Avrillier Jean-Noël Millery Annie Dambrine Etienne 《Ecosystems》2019,22(2):312-330
Ecosystems - When a water reservoir is created, the pre-existing soils and vegetation are flooded. Here, we took advantage of the complete emptying of the Sarrans Reservoir, which was flooded... 相似文献
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Alessandra Vigilante Anna Laddach Nathalie Moens Ruta Meleckyte Andreas Leha Arsham Ghahramani Oliver J. Culley Annie Kathuria Chloe Hurling Alice Vickers Erika Wiseman Mukul Tewary Peter W. Zandstra Richard Durbin Franca Fraternali Oliver Stegle Ewan Birney Fiona M. Watt 《Cell reports》2019,26(8):2078-2087.e3
27.
Meng-Yao Li Bruno Ebel Fabrice Blanchard Cédric Paris Emmanuel Guedon Annie Marc 《Biotechnology and bioengineering》2019,116(5):985-993
The cell-specific growth rate (µ) is a critical process parameter for antibody production processes performed by animal cell cultures, as it describes the cell growth and reflects the cell physiological state. When there are changes in these parameters, which are indicated by variations of µ, the synthesis and the quality of antibodies are often affected. Therefore, it is essential to monitor and control the variations of µto assure the antibody production and achieve high product quality. In this study, a novel approach for on-line estimation of µ was developed based on the process analytical technology initiative by using an in situ dielectric spectroscopy. Critical moments, such as significant µ decreases, were successfully detected by this method, in association with changes in cell physiology as well as with an accumulation of nonglycosylated antibodies. Thus, this method was used to perform medium renewals at the appropriate time points, maintaining the values of µ close to its maximum. Using this method, we demonstrated that the physiological state of cells remained stable, the quantity and the glycosylation quality of antibodies were assured at the same time, leading to better process performances compared with the reference feed-harvest cell cultures carried out by using off-line nutrient measurements. 相似文献
28.
Planting Sentinel European Trees in Eastern Asia as a Novel Method to Identify Potential Insect Pest Invaders 总被引:2,自引:0,他引:2
Alain Roques Jian-ting Fan Béatrice Courtial Yan-zhuo Zhang Annie Yart Marie-Anne Auger-Rozenberg Olivier Denux Marc Kenis Richard Baker Jiang-hua Sun 《PloS one》2015,10(5)
Quarantine measures to prevent insect invasions tend to focus on well-known pests but a large proportion of the recent invaders were not known to cause significant damage in their native range, or were not even known to science before their introduction. A novel method is proposed to detect new potential pests of woody plants in their region of origin before they are introduced to a new continent. Since Asia is currently considered to be the main supplier of insect invaders to Europe, sentinel trees were planted in China during 2007-2011 as an early warning tool to identify the potential for additional Asian insect species to colonize European trees. Seedlings (1-1.5 m tall) of five broadleaved (Quercus petraea, Q. suber, Q. ilex, Fagus sylvatica, and Carpinus betulus) and two conifer species (Abies alba and Cupressus sempervirens) were planted in blocks of 100 seedlings at two widely separated sites (one in a nursery near Beijing and the other in a forest environment near Fuyang in eastern China), and then regularly surveyed for colonization by insects. A total of 104 insect species, mostly defoliators, were observed on these new hosts, and at least six species were capable of larval development. Although a number of the insects observed were probably incidental feeders, 38 species had more than five colonization events, mostly infesting Q. petraea, and could be considered as being capable of switching to European trees if introduced to Europe. Three years was shown to be an appropriate duration for the experiment, since the rate of colonization then tended to plateau. A majority of the identified species appeared to have switched from agricultural crops and fruit trees rather than from forest trees. Although these results are promising, the method is not appropriate for xylophagous pests and other groups developing on larger trees. Apart from the logistical problems, the identification to species level of the specimens collected was a major difficulty. This situation could be improved by the development of molecular databases. 相似文献
29.
Matilda Chelimo Saina Xiuqiong Bi Raphael Lihana Raphael Lwembe Azumi Ishizaki Annie Panikulam Tresa Palakudy Rachel Musoke Mary Owens Elijah Maritim Songok Hiroshi Ichimura 《PloS one》2015,10(8)
Objectives
Disease progression varies among HIV-1-infected individuals. The present study aimed to explore possible viral and host factors affecting disease progression in HIV-1-infected children.Methods
Since 2000, 102 HIV-1 vertically-infected children have been followed-up in Kenya. Here we studied 29 children (15 male/14 female) who started antiretroviral treatment at <5 years of age (rapid progressors; RP), and 32 (17 male/15 female) who started at >10 years of age (slow progressors; SP). Sequence variations in the HIV-1 gag and nef genes and the HLA class I-related epitopes were compared between the two groups.Results
Based on nef sequences, HIV-1 subtypes A1/D were detected in 62.5%/12.5% of RP and 66.7%/20% of SP, with no significant difference in subtype distribution between groups (p = 0.8). In the ten Nef functional domains, only the PxxP3 region showed significantly greater variation in RP (33.3%) than SP (7.7%, p = 0.048). Gag sequences did not significantly differ between groups. The reportedly protective HLA-A alleles, A*74:01, A*32:01 and A*26, were more commonly observed in SP (50.0%) than RP (11.1%, p = 0.010), whereas the reportedly disease-susceptible HLA-B*45:01 was more common in RP (33.3%) than SP (7.4%, p = 0.045). Compared to RP, SP showed a significantly higher median number of predicted HLA-B-related 12-mer epitopes in Nef (3 vs. 2, p = 0.037), HLA-B-related 11-mer epitopes in Gag (2 vs. 1, p = 0.029), and HLA-A-related 9-mer epitopes in Gag (4 vs. 1, p = 0.051). SP also had fewer HLA-C-related epitopes in Nef (median 4 vs. 5, p = 0.046) and HLA-C-related 11-mer epitopes in Gag (median 1 vs. 1.5, p = 0.044) than RP.Conclusions
Compared to rapid progressors, slow progressors had more protective HLA-A alleles and more HLA-B-related epitopes in both the Nef and Gag proteins. These results suggest that the host factor HLA plays a stronger role in disease progression than the Nef and Gag sequence variations in HIV-1-infected Kenyan children. 相似文献30.
Etienne Karita Matt A Price Shabir Lakhi William Kilembe Anatoli Kamali Eugene Ruzagira Eric Hunter Paul Farmer Susan Allen Gwynn Stevens Paramesh Chetty Sabrina Welsh Annie Yang Jill Gilmour Pat Fast The IAVI Africa HIV Prevention Partnership 《PloS one》2015,10(8)