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排序方式: 共有3136条查询结果,搜索用时 15 毫秒
1.
Nitsa Buaron Antonella Mangraviti Francesco Volpin Ann Liu Mariangela Pedone Eric Sankey Dina Aranovich Itay Adar Fausto J. Rodriguez Abraham Nyska Riki Goldbart Tamar Traitel Henry Brem Betty Tyler Joseph Kost 《Advanced functional materials》2021,31(44):2100643
Treating neuroinflammation-related injuries and disorders through manipulation of neuroinflammation functions is being heralded as a new therapeutic strategy. In this study, a novel pectic galactan (PG) polysaccharide based gene therapy approach is developed for targeting reactive gliosis in neuroinflammation. Galectin-3 (Gal-3) is a cell protein with a high affinity to β-galactoside sugars and is highly expressed in reactive gliosis. Since PG carries galactans, it can target reactive gliosis via specific carbohydrate interaction between galactan and Gal-3 on the cell membrane, and therefore can be utilized as a carrier for delivering genes to these cells. The carrier is synthesized by modifying quaternary ammonium groups on the PG. The resulting quaternized PG (QPG) is found to form complexes with plasmid DNA with a mean diameter of 100 nm and have the characteristics required for targeted gene therapy. The complexes efficiently condense large amounts of plasmid per particle and successfully bind to Gal-3. The in vivo study shows that the complexes are biocompatible and safe for administration and can selectively transfect reactive glial cells of an induced cortical lesion. The results confirm that this PG-based delivery system is a promising platform for targeting Gal-3 overexpressing neuroinflammation cells for treating neuroinflammation-related injuries and neurodegenerative diseases. 相似文献
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Abraham G. Alvarado Rosaura Hernández-Montelongo Martin Rabelero Lourdes A. Pérez-Carrillo Jorge E. Puig Francisco López-Serrano 《Polymer Engineering and Science》2020,60(2):223-232
A simple but comprehensive model considering homogeneous and micellar nucleation, coagulation, entry of radicals to particles and to micelles and radicals' exit from particles, is presented. The model is validated, in a starved semicontinuous heterophase polymerization of ethyl methacrylate, at three monomer addition rates. The model accurately describes the overall and instantaneous conversion, the average particle density and diameter, and the number and weight average molar masses evolutions over time. It is found that even though the average number of radicals is much smaller than 0.5, the system is not 0-1. An empirical function was used to describe the gel effect. The homogeneous nucleation was the prevailing mechanism for particle formation and large exit rates of radicals were observed. POLYM. ENG. SCI., 60: 223–232, 2019. © 2019 Society of Plastics Engineers 相似文献
4.
Michelle Abraham 《电子产品世界》2008,(7)
数字视频编码和解码芯片目前需求量很大.在未来几年里,这种芯片的市场将更加强劲地增长.推动这个市场增长的因素有三个:一个是全球范围的从模拟电视向数字电视的过渡,这种过渡将刺激数字接收机和基础设施设备的需求;另一个因素是手机、便携式播放机和汽车内的移动视频功能日益流行;第三个因素是数字视频标准的持续发展将推动对提供高性能芯片的新需求. 相似文献
5.
Paul I. Dalven James R. Hildebrandt Abraham Shamir Anthony J. Laccetti Leonard T. Hodgins Harry P. Gregor 《应用聚合物科学杂志》1985,30(3):1113-1132
Various high molecular weight copolymers of acrylonitrile and a vinyl comonomer containing an aryl amine, a pyridine, or an aliphatic hydroxyl group were synthesized via slurry polymerization techniques so as to contain from 1 to 15 mol % functional comonomer. The comonomer content was quantitated by ultraviolet absorbance, base titration of acid polymer salts, and/or relative chemical reactivity with trichloro-s-triazine. Thin films were cast from copolymer solutions, coagulated into unsupported ultrafiltration membrances, and characterized with respect to both water permeability and pore size distribution. Analysis by size exclusion chromatography of the membrane permeate of a pool of dextran fractions yielded a continuous distribution curve for membrane pore size over the range 1.5 to 70 nm. The ultrafiltration membranes were used for protein immobilization after appropriate chemical activation. The three distinct types of functional copolymers gave comparable results for α-chymotrypsin, with protein weight loadings of 6–12% and 40–65% retention of enzymatic specific activity. 相似文献
6.
Antigen receptor genes are assembled by site-specific DNA rearrangement. The recombination activator genes RAG-1 and RAG-2 are essential for this process, termed V(D)J rearrangement. The activity and stability of the RAG-2 protein have now been shown to be regulated by phosphorylation. In fibroblasts RAG-2 was phosphorylated predominantly at two serine residues, one of which affected RAG-2 activity in vivo. The threonine at residue 490 was phosphorylated by p34cdc2 kinase in vitro; phosphorylation at this site in vivo was associated with rapid degradation of RAG-2. Instability was transferred to chimeric proteins by a 90-residue portion of RAG-2. Mutation of the p34cdc2 phosphorylation site of the tumor suppressor protein p53 conferred a similar phenotype, suggesting that this association between phosphorylation and degradation is a general mechanism. 相似文献
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PI Lobo C Spencer MT Douglas WC Stevenson TL Pruett 《Canadian Metallurgical Quarterly》1993,55(5):1063-1066
Recent reports indicate a higher incidence of both acute and chronic liver allograft rejection when, at the time of transplantation, the recipients serum contains donor-specific anti-HLA antibodies. From 9/89 to 5/91, 133 liver allografts were performed at our institution. Thirteen liver recipients had donor-specific IgG anti-HLA antibodies (complement-fixing) at the time of transplantation. In eleven patients, antibodies reacted to donor class I antigens while in 1 patient the donor-specific antibody had class II reactivity. Twelve patients have been followed for a minimum of 12 months (median 18 months, range 28-12 months). No hyperacute rejection was seen in any of the cases and four patients had acute rejections. Thus far only one of the twelve patients has biopsy evidence suggestive of chronic liver injury. The remaining have normal liver enzymes and bilirubin. Three of these twelve patients died (one from a myocardial infarction and the others from sepsis) accounting for a one-year graft survival of 75%. There was no significant statistical difference in the one-year graft survival in those recipients without donor-specific antibodies (i.e., 80.5%). In eight of the twelve patients, pretransplant preformed antibody level (PRA) was > 50%. In six of the thirteen patients donor-specific antibody was present at dilutions greater than 1:64. As previously reported, the donor-specific antibody disappeared from the serum posttransplant within hours and did not reappear. In vitro studies demonstrated no factor in portal or hepatic artery blood that could inhibit rabbit complement mediated lysis of anti-HLA antibodies. We conclude that it is not a contraindication to do liver transplants in the presence of donor-specific anti-HLA antibodies. 相似文献
9.
CM Wheeler CA Parmenter WC Hunt TM Becker CE Greer A Hildesheim MM Manos 《Canadian Metallurgical Quarterly》1993,20(5):286-289
OBJECTIVES: To confirm the risk factors for genital human papillomavirus (HPV) infection. GOAL OF THIS STUDY: To investigate risk factors for HPV detection apart from the correlated risk factors for cervical neoplasia. STUDY DESIGN: Cervical human papillomavirus (HPV) DNA was assessed in 357 cytologically normal women attending the University of New Mexico student health center. Cervical swab samples were obtained for HPV DNA detection and typing using a PCR-based DNA amplification system. Possible determinants of cervical HPV were examined including age, ethnicity, history of sexually transmitted disease, oral contraceptive use, smoking, age at first intercourse, lifetime number of sex partners, marital status, and history of pregnancy. RESULTS: A 44.3% overall prevalence of cervical HPV was observed. On univariate analysis, factors associated with increasing HPV prevalence included higher lifetime number of sex partners and single marital status. After adjustment for potential confounding variables, we found that HPV prevalence increased with higher lifetime number of sexual partners. CONCLUSION: These findings, along with those from the companion reports in this issue of the journal, support the sexual route of transmission of the virus. 相似文献
10.
BACKGROUND AND STUDY AIMS: Recently, attention has been drawn to the significant occurrence of respiratory and other complications during upper intestinal endoscopy. This prospective study was designed to compare the incidence and severity of oxygen desaturation when two different methods of oxygen delivery were used during elective oesophagogastroduodenoscopy. PATIENTS AND METHODS: After local medical ethics committee approval and written informed consent, one hundred patients undergoing elective oesophagogastroduodenoscopy were randomly allocated to receive supplemental oxygen at either four litres per minute via nasal specular or ten litres per minute through a specially modified non-rebreathing mask. Oxygen saturations during endoscopy facilitated by midazolam sedation were recorded, and non-parametric tests were used to compare the oxygen saturations in the two groups. RESULTS: The mean oxygen saturations were significantly better during the procedure for American Society of Anesthesiology (ASA) grade 2 and 3 patients who received oxygen with the modified mask than for those who received oxygen via nasal specular (98.6% vs. 97.0%, P = 0.004 for ASA grade 2 and 98.4% vs. 95.5, P = 0.006 for ASA grade 3). CONCLUSIONS: For ASA grade 2 and 3 patients, the modified non-rebreathing mask significantly improves oxygen saturations during upper intestinal endoscopy. This technique should be more widely used for patients at moderate and high risk. 相似文献