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排序方式: 共有458条查询结果,搜索用时 31 毫秒
31.
Jolanda?HM?van Bilsen Josée?PA?Wagenaar-Hilbers Maarten?JF?van der Cammen Mariska?EA?van Dijk Willem?van Eden Marca?HM?WaubenEmail author 《Arthritis research & therapy》2002,4(4):R2
We have recently found that matrix metalloproteinases (MMPs) are targets for T-cell and B-cell reactivity in experimental
arthritis. In the present article, we investigate whether modulation of MMP-specific T-cell responses could influence the
course of adjuvant arthritis (AA). Lewis rats were treated nasally with MMP peptides prior to or after AA induction. Administration
of the MMP-10 or the MMP-16 peptide prior to AA induction reduced the arthritic symptoms. In contrast, administration of the
MMP-10 peptide after AA induction aggravated the arthritic symptoms. The present study shows the possible usefulness of MMP
peptides for immunotherapy. However, a clear understanding of proper timing of peptide administration is crucial for the development
of such therapies. 相似文献
32.
Zhao G Wan W Mansouri S Alfaro JF Bassler BL Cornell KA Zhou ZS 《Bioorganic & medicinal chemistry letters》2003,13(22):3897-3900
Bacterial quorum sensing is mediated by autoinducers, small signaling molecules generated by bacteria. It has been proposed that the LuxS enzyme converts S-ribosyl-L-homocysteine to 4,5-dihydroxy-2,3-pentanedione, the precursor of autoinducer 2 (AI-2). We report here a chemical synthesis of S-ribosyl-L-homocysteine and its analogue using Mitsunobu coupling. Chemically synthesized ribosylhomocysteine has been confirmed as a substrate for LuxS in both an enzyme assay and a whole cell quorum sensing assay. The chemical entities of products from the LuxS reaction were also established. Several ribosylhomocysteine analogues have been tested as LuxS inhibitors. 相似文献
33.
We examined the role of Delta signaling in specification of two derivatives in zebrafish neural plate: Rohon-Beard spinal sensory neurons and neural crest. deltaA-expressing Rohon-Beard neurons are intermingled with premigratory neural crest cells in the trunk lateral neural plate. Embryos homozygous for a point mutation in deltaA, or with experimentally reduced delta signalling, have supernumerary Rohon-Beard neurons, reduced trunk-level expression of neural crest markers and lack trunk neural crest derivatives. Fin mesenchyme, a putative trunk neural crest derivative, is present in deltaA mutants, suggesting it segregates from other neural crest derivatives as early as the neural plate stage. Cranial neural crest derivatives are also present in deltaA mutants, revealing a genetic difference in regulation of trunk and cranial neural crest development. 相似文献
34.
Assay of fractions obtained from ion exchange chromatography of papaya latex on CM Sephadex-C50, size exclusion chromatography
on Sephacryl S-300 and size exclusion HPLC have provided an insight into the relative contributions of the gluten-detoxifying
enzymes present. This outcome has been achieved by the use of the above chromatographic techniques, coupled with assays of
lysosomal activity, protease activity using benzylarginine ethyl ester (BAEE) as substrate, prolyl endopeptidase (PEP) using
glycylprolylnitroanilide and a prolidase assay using acetylprolylglycine. These procedures have shown that the activity in
papaya latex is due largely to caricain and to a lesser extent, chymopapain and glutamine cyclotransferase. The presence of
caricain and these other enzymes was confirmed by mass spectrometry of trypsin digests of the most active fraction obtained
by CM Sephadex-C50 chromatography and size exclusion HPLC. Fractions rich in caricain would be suitable for enzyme therapy
in gluten intolerance and appear to have synergistic action with porcine intestinal extracts. 相似文献
35.
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37.
Johnson JE Goulding RE Ding Z Partovi A Anthony KV Beaulieu N Tazmini G Cornell RB Kay RJ 《The Biochemical journal》2007,406(2):223-236
RasGRPs (guanine-nucleotide-releasing proteins) are exchange factors for membrane-bound GTPases. All RasGRP family members contain C1 domains which, in other proteins, bind DAG (diacylglycerol) and thus mediate the proximal signal-transduction events induced by this lipid second messenger. The presence of C1 domains suggests that all RasGRPs could be regulated by membrane translocation driven by C1-DAG interactions. This has been demonstrated for RasGRP1 and RasGRP3, but has not been tested directly for RasGRP2, RasGRP4alpha and RasGRP4beta. Sequence alignments indicate that all RasGRP C1 domains have the potential to bind DAG. In cells, the isolated C1 domains of RasGRP1, RasGRP3 and RasGRP4alpha co-localize with membranes and relocalize in response to DAG, whereas the C1 domains of RasGRP2 and RasGRP4beta do not. Only the C1 domains of RasGRP1, RasGRP3 and RasGRP4alpha recognize DAG as a ligand within phospholipid vesicles and do so with differential affinities. Other lipid second messengers were screened as ligands for RasGRP C1 domains, but none was found to serve as an alternative to DAG. All of the RasGRP C1 domains bound to vesicles which contained a high concentration of anionic phospholipids, indicating that this could provide a DAG-independent mechanism for membrane binding by C1 domains. This concept was supported by demonstrating that the C1 domain of RasGRP2 could functionally replace the membrane-binding role of the C1 domain within RasGRP1, despite the inability of the RasGRP2 C1 domain to bind DAG. The RasGRP4beta C1 domain was non-functional when inserted into either RasGRP1 or RasGRP4, implying that the alternative splicing which produces this C1 domain eliminates its contribution to membrane binding. 相似文献
38.
Genome sequencing and analysis of the versatile cell factory Aspergillus niger CBS 513.88 总被引:1,自引:0,他引:1
Pel HJ de Winde JH Archer DB Dyer PS Hofmann G Schaap PJ Turner G de Vries RP Albang R Albermann K Andersen MR Bendtsen JD Benen JA van den Berg M Breestraat S Caddick MX Contreras R Cornell M Coutinho PM Danchin EG Debets AJ Dekker P van Dijck PW van Dijk A Dijkhuizen L Driessen AJ d'Enfert C Geysens S Goosen C Groot GS de Groot PW Guillemette T Henrissat B Herweijer M van den Hombergh JP van den Hondel CA van der Heijden RT van der Kaaij RM Klis FM Kools HJ Kubicek CP van Kuyk PA Lauber J 《Nature biotechnology》2007,25(2):221-231
39.
Charlie Strange Felix JF Herth Kevin L Kovitz Geoffrey McLennan Armin Ernst Jonathan Goldin Marc Noppen Gerard J Criner Frank C Sciurba 《BMC pulmonary medicine》2007,7(1):1-12
Background
Lung volume reduction surgery is effective at improving lung function, quality of life, and mortality in carefully selected individuals with advanced emphysema. Recently, less invasive bronchoscopic approaches have been designed to utilize these principles while avoiding the associated perioperative risks. The Endobronchial Valve for Emphysema PalliatioN Trial (VENT) posits that occlusion of a single pulmonary lobe through bronchoscopically placed Zephyr® endobronchial valves will effect significant improvements in lung function and exercise tolerance with an acceptable risk profile in advanced emphysema.Methods
The trial design posted on Clinical trials.gov, on August 10, 2005 proposed an enrollment of 270 subjects. Inclusion criteria included: diagnosis of emphysema with forced expiratory volume in one second (FEV1) < 45% of predicted, hyperinflation (total lung capacity measured by body plethysmography > 100%; residual volume > 150% predicted), and heterogeneous emphysema defined using a quantitative chest computed tomography algorithm. Following standardized pulmonary rehabilitation, patients were randomized 2:1 to receive unilateral lobar placement of endobronchial valves plus optimal medical management or optimal medical management alone. The co-primary endpoint was the mean percent change in FEV1 and six minute walk distance at 180 days. Secondary end-points included mean percent change in St. George's Respiratory Questionnaire score and the mean absolute changes in the maximal work load measured by cycle ergometry, dyspnea (mMRC) score, and total oxygen use per day. Per patient response rates in clinically significant improvement/maintenance of FEV1 and six minute walk distance and technical success rates of valve placement were recorded. Apriori response predictors based on quantitative CT and lung physiology were defined.Conclusion
If endobronchial valves improve FEV1 and health status with an acceptable safety profile in advanced emphysema, they would offer a novel intervention for this progressive and debilitating disease.Trial Registration
ClinicalTrials.gov: NCT00129584 相似文献40.
Mukhopadhyay KD Bandyopadhyay A Chang TT Elkahloun AG Cornell JE Yang J Goins BA Yeh IT Sun LZ 《PloS one》2011,6(6):e20473