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21.
Shimaoka M Lu C Salas A Xiao T Takagi J Springer TA 《Proceedings of the National Academy of Sciences of the United States of America》2002,99(26):16737-16741
Conformational movement of the C-terminal alpha7 helix in the integrin inserted (I) domain, a major ligand-binding domain that adopts an alpha/beta Rossmann fold, has been proposed to allosterically regulate ligand-binding activity. Disulfide bonds were engineered here to reversibly lock the position of the alpha7 helix in one of two alternative conformations seen in crystal structures, termed open and closed. Our results show that pairs of residues with Cbeta atoms farther apart than optimal for disulfide bond stereochemistry can be successfully replaced by cysteine, suggesting that backbone movement accommodates disulfide formation. We also find more success with substituting partially exposed than buried residues. Disulfides stabilizing the open conformation resulted in constitutively active alphaMbeta2 heterodimers and isolated alphaM inserted domains, which were reverted to an inactive form by dithiothreitol reduction. By contrast, a disulfide stabilizing the closed conformation resulted in inactive alphaMbeta2 that was resistant to activation but became activatable after dithiothreitol treatment. 相似文献
22.
Adelaida Zabalegui Loreto Macia Josefa Márquez Roser Ricomá Carmen Nuin Isabel Mariscal Azucena Pedraz Concepción Germán Joaquín Moncho 《Journal of nursing scholarship》2006,38(2):114-118
PURPOSE: To provide an overview of changes in nursing education in the European Union (EU) within the framework of the Bologna Declaration, signed in 1999 by the European ministers of education, and to describe specific efforts and changes in Spain. ORGANIZING CONSTRUCTS: (a) the Bologna Declaration process, its recent reforms in all disciplines including nursing, and perspectives on future developments; (b) the Tuning Project, designed and carried out by a group of European universities to meet the challenges posed by the Bologna Declaration; and (c) efforts in a group of Spanish universities to promote higher education in nursing. FINDINGS AND CONCLUSIONS: These changes promote enhanced academic recognition, professionalism in nursing education, and graduates' competencies in practice in most European countries by specifying the undergraduate nursing degree as the minimal entrance level for practice and master's and doctoral programs for further career development. 相似文献
23.
Azucena Castrillo Teresa Jimenez-Marco José L. Arroyo María L. Jurado Luis Larrea Rosa M. Maymo Jorge Monge Carmen Muñoz Ángel Pajares Marta Yáñez 《Transfusion and apheresis science》2017,56(3):357-361
Background
Diverse variables are involved in apheresis platelet collection, processing and storage. This survey shows how these are realized in Spain.Method
An analysis of collected data was performed in a questionnaire completed by ten Transfusion Centers (TC) which perform between 50 and 520 apheresis procedures per month. This information comprises the procedures used to collect, inspect and store apheresis platelet concentrates (PC), and quality control data.Results
Macroscopic inspection of PC is performed in all TC, especially during the first few hours post-collection and before distribution. The type of processor, duration of post-collection resting periods and temperature from the time of collection until distribution are similar in all TC. In 80% of TC, PC with small and scarce aggregates are distributed to transfusion services. The presence of clumps is influenced by type of processor, female donor, cold ambient temperature and collection of hyperconcentrated platelets, and is often recurrent in the same donor, although some TC have not found any influential variables. Overall, no objective inspection methods are followed, although there are exceptions. The degree of compliance with quality control parameters, such as the number of units studied, mean platelet yield, residual leukocyte counts and pH at expiry date, is acceptable in all TC. Compliance in terms of number of microbiological culture samples is variable.Discussion
The usual practice in Spanish TC with respect to the collection, post-collection handling and storage of apheresis PC can be considered uniform, although some specific aspects of analyses should follow more objective methods. 相似文献24.
Evaluation of a Staff Training Programme using Positive Psychology coaching with film and theatre elements in care homes: views and attitudes of residents,staff and relatives
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25.
Decision-making in COPD is complicated by the lack of clear prognostic factors. In this clinical situation it is also necessary to include the desires, values and choices of patients. The problem is more complex in the critical episodes, where the patients are incapable to make decisions. The instruments that allow incapable patients to represent themselves, the kind of patients who could benefit from its use, and the Spanish legislation on the matter, are presented in the first part of the work. The paper goes on to explain how to apply advance directives to the case of COPD. The article concludes that the appropriate use of advance directives and advanced care planning increases the quality of decisions at the end of the life of the patients with COPD." 相似文献
26.
López-Cerero L Egea P Serrano L Navarro D Mora A Blanco J Doi Y Paterson DL Rodríguez-Baño J Pascual A 《International journal of antimicrobial agents》2011,37(4):365-367
Seven phylogroup A CTX-M-15-producing Escherichia coli isolates recovered from clinical and meat samples were further characterised. All of them belonged to sequence type ST410. Only 2 of the 22 virulence genes investigated were detected. All isolates carried the fimH gene encoding type 1 fimbriae, and five isolates harboured the iucD gene encoding aerobactin siderophore. A group of five isolates showed 81.2% similarity by pulsed-field gel electrophoresis (PFGE), comprising three clinical isolates belonging to ONT:H9 and two food isolates belonging to O55:H9. Different HpaI digestion patterns were observed for plasmids, but all of them belonged to IncFIB group and harboured bla(CTX-M-15) associated with bla(OXA-1), bla(TEM), tetA, catB3 and aac(6')-Ib surrounded by an identical genetic environment. These findings showed the possibility of lateral gene transfer of bla(CTX-M-15) as well as other antibiotic resistance determinants between low-virulence food and clinical isolates. 相似文献
27.
Roberto Méndez-Gallart Elina Estévez Adolfo Bautista Pablo Rodríguez Pedro Taboada Azucena L. Armas Jose M. Pradillos Ramiro Varela 《Journal of pediatric surgery》2009,44(10):2048-2053
Purpose
The aim of this study is to evaluate bipolar scissors circumcision by comparing it with standard freehand scalpel procedure.Patients and Methods
Data were analyzed from a prospective, randomized study, comparing 2 different surgical techniques for pediatric circumcision: the bipolar diathermy scissors circumcision technique with those of a conventional scalpel technique. A total of 230 pediatric patients younger than 16 years (115 in each arm of the trial) who were undergoing circumcision were reviewed prospectively. Operative time, surgical bleeding, complications, and postoperative morbidity were analyzed. Differences between bipolar scissors circumcision and conventional surgery were compared.Results
Median blood loss for bipolar circumcision was 0.2 mL (range, 0-0.8 mL) compared with 2.1 mL in the standard group (range, 0.9-4.2 mL) (P < .001). Operative time in the bipolar diathermy treated group was significantly decreased compared with conventionally treated patients (10.8 ± 1.2 vs 19.1 ± 2.6 minutes; P < .01). Early and late postoperative morbidity were significantly decreased in circumcised patients who underwent the bipolar circumcision technique as compared with those who underwent the conventional approach regardless of the postoperative edema (22 vs 10; P = .02).Conclusions
Bipolar scissors circumcision approach is an effective and safe procedure alternative to the standard scalpel technique in pediatric circumcision with no significant morbidity. 相似文献28.
Díaz-Cintra S González-Maciel A Morales MA Aguilar A Cintra L Prado-Alcalá RA 《Experimental neurology》2007,208(1):47-53
In 30- and 90-day-old rats, using immunohistochemistry for glutamic acid decarboxylase 67 (GAD-67), we have tested whether malnutrition during different periods of hippocampal development produces deleterious effects on the population of GABA neurons in the dentate gyrus (DG) and cornu Ammonis (CA1-3) of the dorsal hippocampus. Animals were under one of four nutritional conditions: well-nourished controls (Con), prenatal protein malnourished (PreM), postnatal protein malnourished (PostM), and chronic protein malnourished (ChroM). We found that the number of GAD-67-positive (GAD-67+) interneurons was higher in the DG than in the CA1-3 areas of both Con and malnourished groups. Regarding the DG, the number of GAD-67+ interneurons was increased in PreM and PostM and decreased in ChroM at 30 days. At 90 days of age the number of GAD-67+ interneurons was increased in PostM and ChroM and remained unchanged in PreM. With respect to CA1-3, the number of labeled interneurons was decreased in PostM and ChroM at 30 days of age, but no change was found in PreM. At 90 days no changes in the number of these interneurons were found in any of the groups. These observations suggest that 1) the cell death program starting point is delayed in DG GAD-67+ interneurons, and 2) protein malnutrition differentially affects GAD-67+ interneuron development throughout the dorsal hippocampus. Thus, these changes in the number of GAD-67+ interneurons may partly explain the alterations in modulation of dentate granule cell excitability, as well as in the emotional, motivational, and memory disturbances commonly observed in malnourished rats. 相似文献
29.
Activation of vascular adhesion protein-1 on liver endothelium results in an NF-kappaB-dependent increase in lymphocyte adhesion 总被引:1,自引:0,他引:1
Lalor PF Sun PJ Weston CJ Martin-Santos A Wakelam MJ Adams DH 《Hepatology (Baltimore, Md.)》2007,45(2):465-474
Vascular adhesion protein-1 (VAP-1) is an adhesion molecule and amine oxidase that is expressed at high levels in the human liver. It promotes leukocyte adhesion to the liver in vivo and drives lymphocyte transmigration across hepatic sinusoidal endothelial cells in vitro. We report that in addition to supporting leukocyte adhesion, provision of specific substrate to VAP-1 results in hepatic endothelial cell activation, which can be abrogated by treatment with the enzyme inhibitor semicarbazide. VAP-1-mediated activation was rapid; dependent upon nuclear factor-kappaB, phosphatidylinositol-3 kinase, and mitogen-activated protein kinase pathways; and led to upregulation of the adhesion molecules E-selectin, intercellular adhesion molecule-1, and vascular cell adhesion molecule-1 and secretion of the chemokine CXCL8. This response resulted in enhanced lymphocyte adhesion, was restricted to hepatic endothelial cells that expressed VAP-1, and was not observed in human umbilical vein endothelial cells. Conclusion: We propose that as well as directly promoting adhesion via interactions with the as yet unknown ligand, binding of enzyme substrate to VAP-1 can indirectly promote inflammatory cell recruitment via upregulation of adhesion molecules and chemokines. This response is likely to be important for the recruitment of leukocytes to the liver and suggests that VAP-1 inhibitors have therapeutic potential for treating chronic inflammatory liver disease. 相似文献
30.
Margarita Martinez-Medina Azucena Mora Miguel Blanco Cecilia López María Pilar Alonso Stéphane Bonacorsi Marie-Hélène Nicolas-Chanoine Arlette Darfeuille-Michaud Jesus Garcia-Gil Jorge Blanco 《Journal of clinical microbiology》2009,47(12):3968-3979
Adherent-invasive Escherichia coli (AIEC) pathovar strains, which are associated with Crohn''s disease, share many genetic and phenotypic features with extraintestinal pathogenic E. coli (ExPEC) strains, but little is known about the level of genetic similarity between the two pathovars. We aimed to determine the frequency of strains with the “AIEC phenotype” among a collection of ExPEC strains and to further search for a common phylogenetic origin for the intestinal and extraintestinal AIEC strains. The adhesion, invasion, and intramacrophage replication capabilities (AIEC phenotype) of 63 ExPEC strains were determined. Correlations between virulence genotype and AIEC phenotype and between intestinal/extraintestinal origin, serotype, and phylogroup were evaluated for the 63 ExPEC and 23 intestinal AIEC strains. Phylogenetic relationships between extraintestinal and intestinal AIEC strains were determined using multilocus sequence typing (MLST) and pulsed-field gel electrophoresis. Only four (6.35%) ExPEC strains, belonging to the O6:H1, O83:H1, and O25:H4 serotypes, were classified as having an AIEC phenotype. These strains were found to be genetically related to some intestinal AIEC strains of the same serotypes as revealed by MLST. No particular virulence gene sets correlated with the intestinal/extraintestinal origin of the strains or with the AIEC phenotype, whereas the gene sets did correlate with the serogroup. We identified two intestinal AIEC strains and one extraintestinal AIEC strain belonging to the O25:H4 serotype that also belonged to the emerging and virulent clonal group ST131. In conclusion, the ExPEC and AIEC pathovars share similar virulence gene sets, and certain strains are phylogenetically related. However, the majority of ExPEC strains did not behave like AIEC strains, thus confirming that the AIEC pathovar possesses virulence-specific features that, to date, are detectable only phenotypically.Members of the Enterobacteriaceae family, especially Escherichia coli, have been repeatedly suggested to play a role in the origin and/or perpetuation of Crohn''s disease (CD). In part, this suggestion was based on the higher abundance of this bacterium in CD patients than in control subjects (4, 10, 20, 23, 28, 29, 32, 41, 48, 51). Although considerable effort has been devoted to the search for intestinal pathogenic E. coli strains associated with CD, to date none of the six previously described pathovars (27) has been implicated in this condition. Darfeuille-Michaud et al. (18) observed that E. coli strains with adhesion and invasion properties colonized the ileal mucosae of CD patients more frequently than those of control subjects. Darfeuille-Michaud et al. further characterized these strains and proposed a new potential E. coli pathovar associated with CD, which was designated adherent-invasive E. coli (AIEC) (10). The implication of AIEC in CD is becoming increasingly relevant because several independent studies from different countries have reported a higher prevalence of invasive E. coli in CD patients (4, 17, 33, 34, 47).The main characteristics of AIEC are (i) the ability to adhere to and invade intestinal epithelial cells, (ii) the ability to survive and replicate expansively within macrophages without triggering host cell death and inducing the release of tumor necrosis factor alpha (21), and (iii) the lack of known invasive determinants (17). Recently, Glasser and Darfeuille-Michaud (22) proposed a model explaining the mechanism of pathogenesis for AIEC strains. The AIEC strains isolated to date are clonally diverse and belong to distinct serotypes. Moreover, despite the fact that they fall primarily into the B2 phylogroup, AIEC strains belonging to the A, B1, and D phylogroups have also been isolated (4, 33-35, 47). Although no specific virulence factors have been described for this pathovar, AIEC strains carry many virulence-associated genes characteristic of extraintestinal pathogenic E. coli (ExPEC) strains, which suggests that the AIEC pathovar could be closely related to the ExPEC pathovar (4, 17, 34).The aim of this work was to determine the frequency of strains with the “AIEC phenotype” among E. coli strains that cause extraintestinal infections, including uropathogenic E. coli (UPEC), septicemic E. coli, and neonatal meningitis E. coli strains. To achieve this objective, we determined the ability of a collection of ExPEC strains to adhere to and invade intestinal epithelial cells, as well as their capacity to survive and replicate within macrophages. In parallel, we compared the distributions of virulence-associated genes among ExPEC and AIEC strains. Furthermore, we searched for a common phylogenetic origin of the ExPEC strains that had an AIEC phenotype (referred to in this study as extraintestinal AIEC) and a collection of AIEC strains isolated mainly from the intestinal mucosae of CD patients (intestinal AIEC). 相似文献