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排序方式: 共有251条查询结果,搜索用时 15 毫秒
1.
Macarena Gomez-Lira Antonella Sangalli Monica Mottes Chiara Perusi Pier Franco Pignatti Nicolò Rizzuto Alessandro Salviati 《Human genetics》1995,96(4):417-422
-Hexosaminidase gene mutations were analyzed in two adult-onset Sandhoff disease Italian patients by PCR analysis of a common known mutation (5) and by heteroduplex analysis of genomic and RT-PCR DNA fragments, covering the whole gene. The patients' genotypes were 5/C1214T, and G890A/C1214T, respectively. As mutation C1214T (Pro405Leu) is also present in the other two late-onset cases so far described, we suggest that C1214T is a common mutation in this type of Sandhoff disease. Mutation G890A (Cys297Tyr) is a novel mutation which presumably causes altered processing of the pro chain. 相似文献
2.
Paola Navarrete Fabien Magne Pamela Mardones Macarena Riveros Rafael Opazo Antonia Suau Philippe Pochart & Jaime Romero 《FEMS microbiology ecology》2010,71(1):148-156
The aim of this study was to evaluate different molecular tools based on the 16S rRNA gene, internal transcribed spacer, and the rpo B gene to examine the bacterial populations present in juvenile rainbow trout intestines. DNA was extracted from both pooled intestinal samples and bacterial strains. Genes were PCR-amplified and analysed using both temporal temperature gradient gel electrophoresis (TTGE) and restriction fragment length polymorphism methods. Because of the high cultivability of the samples, representative bacterial strains were retrieved and we compared the profiles obtained from isolated bacteria with the profile of total bacteria from intestinal contents. Direct analysis based on rpo B-TTGE revealed a simple bacterial composition with two to four bands per sample, while the 16S rRNA gene-TTGE showed multiple bands and comigration for a few species. Sequencing of the 16S rRNA gene- and rpo B-TTGE bands revealed that the intestinal microbiota was dominated by Lactococcus lactis, Citrobacter gillenii, Kluyvera intermedia, Obesumbacterium proteus , and Shewanella marinus . In contrast to 16S rRNA gene-TTGE, rpo B-TTGE profiles derived from bacterial strains produced one band per species. Because the single-copy state of rpo B leads to a single band in TTGE, the rpo B gene is a promising molecular marker for investigating the bacterial community of the rainbow trout intestinal microbiota. 相似文献
3.
Plant Ecology - The distribution pattern of perennial native grasses in the dune systems of the Monte desert might be determined by the ability of plant roots to acquire water under drought... 相似文献
4.
Francisco Javier Blancas Mercedes González Macarena Lozano-Oyola Fátima Pérez 《Ecological Indicators》2010,10(2):484-492
This paper introduces an indicator system to evaluate sustainability in established coastal tourism destinations, applying the recommendations and definitions of the World Tourism Organization (WTO). We also develop a new synthetic indicator to simplify the measurement of sustainability and facilitate the comparative analysis of destination ranking. This measurement was obtained by applying a procedure to reduce the number of subjective decisions made by the analyst, using a novel two-stage aggregation methodology based on principal component analysis and on the distance to a reference point. The synthetic indicator obtained was applied to Spanish coastal destinations, and the results serve as a guideline for tourism planning. The conclusions of this research can be extrapolated to the study of other tourism destinations. 相似文献
5.
Nicolás O. Amiano María J. Costa R. Macarena Reiteri Cristian Payés Diego Guerrieri Nancy L. Tateosian Mercedes L. Sánchez Paulo C. Maffia Miriam Diament Romina Karas Andrés Orqueda Miguel Rizzo Laura Alaniz Guillermo Mazzolini Slobodanka Klein Jean‐Michel Sallenave H. Eduardo Chuluyan 《Journal of cellular physiology》2013,228(2):469-475
Secretory leukocyte protease inhibitor (SLPI) is a serine protease inhibitor that was related to cancer development and metastasis dissemination on several types of tumors. However, it is not known the effect of SLPI on mammary and colon tumors. The aim of this study was to examine the effect of SLPI on mammary and colon tumor growth. The effect of SLPI was tested on in vitro cell apoptosis and in vivo tumor growth experiments. SLPI over‐expressing human and murine mammary and colon tumor cells were generated by gene transfection. The administration of murine mammary tumor cells over‐expressing high levels of SLPI did not develop tumors in mice. On the contrary, the administration of murine colon tumor cells over‐expressing SLPI, developed faster tumors than control cells. Intratumoral, but not intraperitoneal administration of SLPI, delayed the growth of tumors and increased the survival of mammary but not colon tumor bearing mice. In vitro culture of mammary tumor cell lines treated with SLPI, and SLPI producer clones were more prone to apoptosis than control cells, mainly under serum deprivation culture conditions. Herein we demonstrated that SLPI induces the apoptosis of mammary tumor cells in vitro and decreases the mammary but not colon tumor growth in vivo. Therefore, SLPI may be a new potential therapeutic tool for certain tumors, such as mammary tumors. J. Cell. Physiol. 228: 469–475, 2013. © 2012 Wiley Periodicals, Inc. 相似文献
6.
Andrés Marcoleta Macarena Marín Gabriela Mercado José María Valpuesta Octavio Monasterio Rosalba Lagos 《Journal of bacteriology》2013,195(17):3995-4004
Microcin E492, a channel-forming bacteriocin with the ability to form amyloid fibers, is exported as a mixture of two forms: unmodified (inactive) and posttranslationally modified at the C terminus with a salmochelin-like molecule, which is an essential modification for conferring antibacterial activity. During the stationary phase, the unmodified form accumulates because expression of the maturation genes mceIJ is turned off, and microcin E492 is rapidly inactivated. The aim of this work was to demonstrate that the increase in the proportion of unmodified microcin E492 augments the ability of this bacteriocin to form amyloid fibers, which in turn decreases antibacterial activity. To this end, strains with altered proportions of the two forms were constructed. The increase in the expression of the maturation genes augmented the antibacterial activity during all growth phases and delayed the loss of activity in the stationary phase, while the ability to form amyloid fibers was markedly reduced. Conversely, a higher expression of microcin E492 protein produced concomitant decreases in the levels of the modified form and in antibacterial activity and a substantial increase in the ability to form amyloid fibers. The same morphology for these fibers, including those formed by only the unmodified version, was observed. Moreover, seeds formed using exclusively the nonmodified form were remarkably more efficient in amyloid formation with a shorter lag phase, indicating that the nucleation process is probably improved. Unmodified microcin E492 incorporation into amyloid fibers was kinetically more efficient than the modified form, probably due to the existence of a conformation that favors this process. 相似文献
7.
8.
Jose L. López-Campos Maria Abad Arranz Carmen Calero-Acu?a Fernando Romero-Valero Ruth Ayerbe-García Antonio Hidalgo-Molina Ricardo I. Aguilar-Pérez-Grovas Francisco García-Gil Francisco Casas-Maldonado Laura Caballero-Ballesteros María Sánchez-Palop Dolores Pérez-Tejero Alejandro Segado Jose Calvo-Bonachera Bárbara Hernández-Sierra Adolfo Doménech Macarena Arroyo-Varela Francisco González-Vargas Juan J. Cruz-Rueda 《PloS one》2016,11(3)
Objectives
Previous clinical audits of COPD have provided relevant information about medical intervention in exacerbation admissions. The present study aims to evaluate adherence to current guidelines in COPD through a clinical audit.Methods
This is a pilot clinical audit performed in hospital outpatient respiratory clinics in Andalusia, Spain (eight provinces with more than 8 million inhabitants), including 9 centers (20% of the public centers in the area) between 2013 and 2014. Cases with an established diagnosis of COPD based on risk factors, clinical symptoms, and a post-bronchodilator FEV1/FVC ratio of less than 0.70 were deemed eligible. The performance of the outpatient clinics was benchmarked against three guidance documents available at the time of the audit. The appropriateness of the performance was categorized as excellent (>80%), good (60−80%), adequate (40−59%), inadequate (20−39%), and highly inadequate (<20%).Results
During the audit, 621 clinical records were audited. Adherence to the different guidelines presented a considerable variability among the different participating hospitals, with an excellent or good adherence for symptom recording, MRC or CAT use, smoking status evaluation, spirometry, or bronchodilation therapy. The most outstanding areas for improvement were the use of the BODE index, the monitoring of treatments, the determination of alpha1-antitrypsin, the performance of exercise testing, and vaccination recommendations.Conclusions
The present study reflects the situation of clinical care for COPD patients in specialized secondary care outpatient clinics. Adherence to clinical guidelines shows considerable variability in outpatient clinics managing COPD patients, and some aspects of the clinical care can clearly be improved. 相似文献9.
Piñeiro D González VM Hernández-Jiménez M Salinas M Martín ME 《Experimental cell research》2007,313(17):3694-3706
Changes to the translational machinery that occur during apoptosis have been described in the last few years. The two principal ways in which translational factors are modified during apoptosis are: (i) changes in protein phosphorylation and (ii) specific proteolytic cleavages. Taxol, a member of a new class of anti-tubulin drugs, is currently used in chemotherapeutic treatments of different types of cancers. We have previously demonstrated that taxol induces calpain-mediated apoptosis in NIH3T3 cells [Pi?eiro et al., Exp. Cell Res., 2007, 313:369-379]. In this study we found that translation was significantly inhibited during taxol-induced apoptosis in these cells. We have studied the phosphorylation status and expression levels of eIF2a, eIF4E, eIF4G and the regulatory protein 4E-BP1, all of which are implicated in translation regulation. We found that taxol treatment did not induce changes in eIF2alpha phosphorylation, but strongly decreased eIF4G, eIF4E and 4E-BP1 expression levels. MDL28170, a specific inhibitor of calpain, prevented reduction of eIF4G, but not of eIF4E or 4E-BP1 levels. Moreover, the calpain inhibitor did not block taxol-induced translation inhibition. All together these findings demonstrated that none of these factors are responsible for the taxol-induced protein synthesis inhibition. On the contrary, taxol treatment increased elongation factor eEF2 phosphorylation in a calpain-independent manner, supporting a role for eEF2 in taxol-induced translation inhibition. 相似文献
10.
Separate taurine and chloride efflux pathways activated during regulatory volume decrease 总被引:6,自引:0,他引:6
Stutzin Andres; Torres Ruben; Oporto Macarena; Pacheco Patricio; Eguiguren Ana Luisa; Cid L. Pablo; Sepulveda Francisco V. 《American journal of physiology. Cell physiology》1999,277(3):C392
Organic osmolyte and halide permeability pathways activated inepithelial HeLa cells by cell swelling were studied by radiotracer efflux techniques and single-cell volume measurements. The replacement of extracellular Cl byanions that are more permeant through the volume-activated Cl channel, as indicated byelectrophysiological measurements, significantly decreasedtaurine efflux. In the presence of less-permeant anions, an increase intaurine efflux was observed. Simultaneous measurement of the125I, used as a tracer forCl, and[3H]taurine effluxshowed that the time courses for the two effluxes differed. InCl-rich medium the increasein I efflux was transient,whereas that for taurine was sustained. OsmosensitiveCl conductance, assessed bymeasuring changes in cell volume, increased rapidly after hypotonicshock. The influx of taurine was able to counteractCl conductance-dependentcell shrinkage but only ~4 min after triggering cell swelling. Thistaurine-induced effect was blocked by DIDS. Differences in anionsensitivity, the time course of activation, and sensitivity to DIDSsuggest that the main cell swelling-activated permeability pathways fortaurine and Cl are separate. 相似文献