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71.
Mauro C Vito P Mellone S Pacifico F Chariot A Formisano S Leonardi A 《Biochemical and biophysical research communications》2003,309(1):84-90
Nuclear factor kappaB (NF-kappaB) plays a pivotal role in numerous cellular processes, including stress response, inflammation, and protection from apoptosis. Therefore, the activity of NF-kappaB needs to be tightly regulated. We have previously identified a novel gene, named CIKS (connection to IkappaB-kinase and SAPK), able to bind the regulatory sub-unit NEMO/IKKgamma and to activate NF-kappaB. Here, we demonstrate that CIKS forms homo-oligomers, interacts with NEMO/IKKgamma, and is recruited to the IKK-complex upon cell stimulation. In addition, we identified the regions of CIKS responsible for these functions. We found that the ability of CIKS to oligomerize, and to be recruited to the IKK-complex is not sufficient to activate the NF-kappaB. In fact, a deletion mutant of CIKS able to oligomerize, to interact with NEMO/IKKgamma, and to be recruited to the IKK-complex does not activate NF-kappaB, suggesting that CIKS needs a second level of regulation to efficiently activate NF-kappaB. 相似文献
72.
Bettler E Imberty A Priem B Chazalet V Heyraud A Joziasse DH Geremia RA 《Biochemical and biophysical research communications》2003,302(3):620-624
The synthesis of sufficient amounts of oligosaccharides is the bottleneck for the study of their biological function and their possible use as drug. As an alternative for chemical synthesis, we propose to use Escherichia coli as a "living factory." We have addressed the production of the Galp alpha(1-3)Galp beta(1-4)GlcNAc epitope, the major porcine antigen responsible for xenograft rejection. An E. coli strain was generated which simultaneously expresses NodC (to provide the chitin-pentaose acceptor), beta(1-4) galactosyltransferase LgtB, and bovine alpha(1-3) galactosyltransferase GstA. This strain produced 0.68 g/L of the heptasaccharide Galp alpha(1-3)Galp beta(1-4)(GlcNAc)(5), which harbours the xenoantigen at its non-reducing end, establishing the feasibility of this approach. 相似文献
73.
Robarge MJ Bom DC Tumey LN Varga N Gleason E Silver D Song J Murphy SM Ekema G Doucette C Hanniford D Palmer M Pawlowski G Danzig J Loftus M Hunady K Sherf BA Mays RW Stricker-Krongrad A Brunden KR Harrington JJ Bennani YL 《Bioorganic & medicinal chemistry letters》2005,15(6):1749-1753
The chemoattractant receptor-homologous molecule expressed on T(H)2 cells (CRTH-2), also found on eosinophils and basophils, is a prostaglandin D2 receptor involved in the recruitment of these cell types during an inflammatory response. In this report, we describe the synthesis and optimization of a ramatroban isostere that is a selective and potent antagonist of CRTH-2 which may be useful in the treatment of certain diseases. 相似文献
74.
Common generalized vitiligo is an acquired depigmenting disorder characterized by a chronic and progressive loss of melanocytes from the epidermis and follicular reservoir. However, the mechanism of melanocyte disappearance has never been clearly understood, and the intervention of cellular and humoral autoimmune phenomena as primary events remains unproven. In this review, is discussed the data supporting the major theories of vitiligo, namely melanocyte destruction (autoimmune, neural and impaired redox status) and melanocyte inhibition or defective adhesion. Based on recent morphologic findings in vivo supporting a chronic detachment and transepidermal loss of melanocytes in common generalized vitiligo, a new theory is suggested proposing melanocytorrhagy as the primary defect underlying melanocyte loss, integrating most of the possible triggering/precipitating/enhancing effects of other known factors. 相似文献
75.
This report describes a new method allowing to measure the three-dimensional forces applied on right and left pedals during cycling. This method is based on a cycle ergometer mounted on a force platform. By recording the forces applied on the force platform and applying the fundamental mechanical equations, it was possible to calculate the instantaneous three-dimensional forces applied on pedals. It was validated by static and dynamic tests. The accuracy of the present system was -7.61 N, -3.37 N and -2.81 N, respectively, for the vertical, the horizontal and the lateral direction when applying a mono-directional force and -4.52 N when applying combined forces. In pedaling condition, the orientation and magnitude of the pedal forces were comparable to the literature. Moreover, this method did not modify the mechanical properties of the pedals and offered the possibility for pedal force measurement with materials often accessible in laboratories. Measurements obtained showed that this method has an interesting potential for biomechanical analyses in cycling. 相似文献
76.
Ajoy Basak Alain Boudreault Andrew Chen Michel Chrtien Nabil G. Seidah Claude Lazure 《Journal of peptide science》1995,1(6):385-395
Antiserum against an N-terminal sequence of murine prohormone convertase-1 (mPC1) incorporating the sequence immediatley following the junction between the putative pro-region and the active enzyme was obtained. This was accomplished using the multiple antigenic peptide (MAP) approach whereupon an 8-branched polylysine core to which are grafted multiple copies of a 16 amino acid peptide representing the N-terminal sequence of mPC1 (positions 84–99) was synthesized by solid-phase Fmoc chemistry. The ensuing peptide was purified and fully characterized by RP-HPLC, 1H-NMR, amino acid composition, peptide sequencing and ion-spray mass spectrometry. The immunological properties of the resulting antibodies in detecting recombinant PC1 in both crude and purified preparations were compared with antibodies raised against a similar N-terminal segment of PC1 but using the conventioanl method of peptide–carrier protein conjugation and also developed against a C-terminal fusion protein of PC1. Our data indicate that the MAP antibody was as efficient as both the amino and carboxy-terminal antibodies in qualitative as well as quantitative analysis of PC1 encoded protein by radioimmunoassay. Following an identical approach, antibodies against other prohormone convertases like furin, PC5/6 and PACE4 were also developed and subsequently applied to a number of biochemical and immunological studies. In each case, the ease of preparation and high immunogenicity of the MAP approach were confirmed and reside in the simplicity and rapidity with which a potent and useful antiserum is obtained. 相似文献
77.
A chemical investigation by headspace SPME and GC-MS of volatile and semi-volatile terpenes in various olibanum samples 总被引:1,自引:0,他引:1
Six different olibanum samples with certified botanical origin were analyzed by headspace SPME-GC/MS in order to define their mono-, sesqui- and diterpenic composition, as pertinent criteria of identification. Boswellia carteri and Boswellia sacra olibanum have quite similar chemical composition, with isoincensole acetate as the main diterpenic biomarker. Although Boswellia serrata olibanum also exhibits this biomarker, the presence of methylchavicol, methyleugenol and an unidentified oxygenated sesquiterpene distinguishes B. serrata olibanum from the two other species. The characteristic chemical compounds of Boswellia papyrifera are the diterpenic biomarkers incensole and its oxide and acetate derivatives, n-octanol and n-octyl acetate. Boswellia frereana olibanum is devoid of diterpenes of the incensole family but contains a high amount of many dimers of alpha-phellandrene. The chemical composition of olibanum, which is demonstrated to be different for each Boswellia species allowed the determination of the taxonomic origin of frankincense samples purchased on various markets in East Africa, in the Near East and in Yemen. Moreover, terpenic fingerprints allowed the botanical origin of olibanum used in traditional incense mixtures to be identified. Furthermore, this study gave us the opportunity to assign a botanical origin to an archaeological frankincense sample. 相似文献
78.
Nhu H. Nguyen Laura J. Williams John B. Vincent Artur Stefanski Jeannine Cavender‐Bares Christian Messier Alain Paquette Dominique Gravel Peter B. Reich Peter G. Kennedy 《Molecular ecology》2016,25(16):4032-4046
Exploring the link between above‐ and belowground biodiversity has been a major theme of recent ecological research, due in large part to the increasingly well‐recognized role that soil microorganisms play in driving plant community processes. In this study, we utilized a field‐based tree experiment in Minnesota, USA, to assess the effect of changes in plant species richness and phylogenetic diversity on the richness and composition of both ectomycorrhizal and saprotrophic fungal communities. We found that ectomycorrhizal fungal species richness was significantly positively influenced by increasing plant phylogenetic diversity, while saprotrophic fungal species richness was significantly affected by plant leaf nitrogen content, specific root length and standing biomass. The increasing ectomycorrhizal fungal richness associated with increasing plant phylogenetic diversity was driven by the combined presence of ectomycorrhizal fungal specialists in plots with both gymnosperm and angiosperm hosts. Although the species composition of both the ectomycorrhizal and saprotrophic fungal communities changed significantly in response to changes in plant species composition, the effect was much greater for ectomycorrhizal fungi. In addition, ectomycorrhizal but not saprotrophic fungal species composition was significantly influenced by both plant phylum (angiosperm, gymnosperm, both) and origin (Europe, America, both). The phylum effect was caused by differences in ectomycorrhizal fungal community composition, while the origin effect was attributable to differences in community heterogeneity. Taken together, this study emphasizes that plant‐associated effects on soil fungal communities are largely guild‐specific and provides a mechanistic basis for the positive link between plant phylogenetic diversity and ectomycorrhizal fungal richness. 相似文献
79.
Recent publications have established the pulse oxygen saturation (SpO2) threshold of 90% for the hospitalization and discharge of infant patients with bronchiolitis. However, there is no clear recommendation regarding the Emergency Department (ED) observation period necessary before allowing safe home discharge for patients with SpO2 above 90%-92%. Our primary aims were to evaluate the risk factors associated with delayed desaturation in infants with SpO2 ≥ 92% on arrival at the ED as well as the ED observation period necessary before allowing safe home discharge. A secondary aim was to identify the risk factors for ED readmission. Of 581 episodes of bronchiolitis in patients < 1 year old admitted to the ED, only 47 (8%) had SpO2 < 92% on arrival there, although 106 (18%) exhibited a delayed desaturation (to < 92%) during ED observation. Female sex, age < 3 months old, ED readmission, more severe initial clinical presentation, and higher pCO2 level (> 6KPa) were risk factors for delayed desaturation with OR varying from 1.7 to 7.5. In patients < 3 months old, mean desaturation occured later than in older patients [6.0 hours (IQR 3.0–14.0) vs. 3.0 hours (IQR 2.0–6.0), P = 0.0018]. In 95% of patients with a delayed desaturation this decrease occurred within 25 hours for patients < 3 months old and within 11 hours for patients ≥ 3 months old. In patients < 3 months old with respiratory rates above the normal range for their age the desaturation occurred earlier than in patients < 3 months with normal respiratory rates [4.4 hours (IQR 3.0–11.7) vs. 14.6 hours (IQR 7.6–22.2), P = 0.037]. Based on the present study’s results, we propose a five step guide for pediatricians on discharging children with bronchiolitis from the ED. By using the threshold of an 11 hour ED observation period for patients ≥ 3 months old and a 25 hour period for patients < 3 months old we are able to detect 95% of the patients with bronchiolitis who are at risk of delayed desaturation. 相似文献
80.
The excavations of several open air sites in Northern France and, especially in the Somme basin, have given numerous data concerning the age and the environment of the human occupations for the period from MIS 12 to MIS 8. The quality of the raw material and the function of the different sites have a great effect on the composition of the lithic assemblages as it has been seen for the different sites located near the confluence of the Somme and Avre (Cagny-la Garenne, Cagny-l’Épinette, Ferme de l’Épinette, Gentelles). The characteristics of the lithic industries of Gouzeaucourt show the complexity of the transition from Lower to Middle Palaeolithic. 相似文献