14 research outputs found
Do biomedical engineers dream of graphene sheets?
During the past few years, graphene has outstandingly emerged as a key nanomaterial for boosting the performance of commercial, industrial and scientific related technologies. The popularity of this novel nanomaterial in biomedical engineering is due to its excellent biological, electronic, optical and thermal properties that, as a whole, surpasses the features of commonly used biomaterials and consequently open a wide range of applications so far within the reach of science fiction. In this minireview, the potential of graphene and its based materials in the expanding biomedical field is highlighted with focus on groundbreaking diagnostic, monitoring and therapeutic strategies. Some of the major challenges related to the synthesis and safety of graphene-based materials are also briefly discussed because of their critical importance in bringing this class of carbon materials closer to the clinic.publishe
Constitutively altered frequencies of circulating follicullar helper T cell counterparts and their subsets in rheumatoid arthritis
El Niño and La Niña influence on droughts at different timescales in the Iberian Peninsula
18 pĂĄginas, 15 figuras, 1 tabla.This paper seeks to determine the impact of extreme phases of the Southern
Oscillation (SO, El Niño/La Niña) on droughts in the Iberian Peninsula. For this purpose,
51 precipitation series (1910â2000) were used. A spatial classification based on monthly
precipitation records was made to identify homogeneous regions and to analyze any
spatial differences in the influence of these extreme phases. For each region a drought
index was calculated (standardized precipitation index) at timescales of 1, 3, 6 and
12 months. El Niño and La Niña years were identified using the Southern Oscillation
index (SOI), in line with studies conducted elsewhere. Mean values of the drought index
were calculated each month for the four timescales during El Niño and La Niña years
as well as for the year following these events. The statistical significance of any anomalies
was evaluated by means of the nonparametric Wilcoxon Mann-Whitney test. The
results indicate that extreme phases of the SO significantly affect the occurrence of
droughts in the Iberian Peninsula. Moreover, spatial and temporal differences, depending
on the timescale used, were identified. Large areas of the Iberian Peninsula are affected by
significant negative values of SPI during the final months of La Niña years and the
initial months of the following year. In contrast, other areas are affected by dry conditions
during the first months of El Niño years as well as during the summers and autumns of the
following year. The spatial differences in drought conditions during extreme phases
of the SO are noticeable, and the drought signal is more consistent for La Niña than it is
for El Niño years. Finally, the usefulness of these results for drought prediction and early
warning systems is discussed.The author wants to acknowledge financial
support from the following projects: BSO2002-02743 and REN2003-07453
(Financed by Ministerio de EducaciĂłn, Cultura y Deporte Spain and
FEDER) and ââPrograma de grupos de investigaciĂłn consolidadosââ (grupo
Clima, Cambio Global y Sistemas Naturales, BOA 147 of 18-12-2002),
financed by AragĂłn Government. Research of the author was supported by
postdoctoral fellowships by the Ministerio de EducaciĂłn, Cultura y
Deporte, Spain.Peer reviewe
El Niño and La Niña influence on droughts at different timescales in the Iberian Peninsula
Complex multiple risk intervention to promote healthy behaviours in people between 45 to 75Â years attended in primary health care (EIRA study): study protocol for a hybrid trial
Epidemiology of surgery associated acute kidney injury (EPIS-AKI): a prospective international observational multi-center clinical study
Purpose: The incidence, patient features, risk factors and outcomes of surgery-associated postoperative acute kidney injury (PO-AKI) across different countries and health care systems is unclear. Methods: We conducted an international prospective, observational, multi-center study in 30 countries in patients undergoing major surgery (>â2-h duration and postoperative intensive care unit (ICU) or high dependency unit admission). The primary endpoint was the occurrence of PO-AKI within 72 h of surgery defined by the Kidney Disease: Improving Global Outcomes (KDIGO) criteria. Secondary endpoints included PO-AKI severity and duration, use of renal replacement therapy (RRT), mortality, and ICU and hospital length of stay. Results: We studied 10,568 patients and 1945 (18.4%) developed PO-AKI (1236 (63.5%) KDIGO stage 1500 (25.7%) KDIGO stage 2209 (10.7%) KDIGO stage 3). In 33.8% PO-AKI was persistent, and 170/1945 (8.7%) of patients with PO-AKI received RRT in the ICU. Patients with PO-AKI had greater ICU (6.3% vs. 0.7%) and hospital (8.6% vs. 1.4%) mortality, and longer ICU (median 2 (Q1-Q3, 1-3) days vs. 3 (Q1-Q3, 1-6) days) and hospital length of stay (median 14 (Q1-Q3, 9-24) days vs. 10 (Q1-Q3, 7-17) days). Risk factors for PO-AKI included older age, comorbidities (hypertension, diabetes, chronic kidney disease), type, duration and urgency of surgery as well as intraoperative vasopressors, and aminoglycosides administration. Conclusion: In a comprehensive multinational study, approximately one in five patients develop PO-AKI after major surgery. Increasing severity of PO-AKI is associated with a progressive increase in adverse outcomes. Our findings indicate that PO-AKI represents a significant burden for health care worldwide