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81.
A Pilot Study Identifying a Set of microRNAs As Precise Diagnostic Biomarkers of Acute Kidney Injury
Elia Aguado-Fraile Edurne Ramos Elisa Conde Macarena Rodríguez Laura Martín-Gómez Aurora Lietor ángel Candela Belen Ponte Fernando Lia?o María Laura García-Bermejo 《PloS one》2015,10(6)
In the last decade, Acute Kidney Injury (AKI) diagnosis and therapy have not notably improved probably due to delay in the diagnosis, among other issues. Precocity and accuracy should be critical parameters in novel AKI biomarker discovery. microRNAs are key regulators of cell responses to many stimuli and they can be secreted to the extracellular environment. Therefore, they can be detected in body fluids and are emerging as novel disease biomarkers. We aimed to identify and validate serum miRNAs useful for AKI diagnosis and management. Using qRT-PCR arrays in serum samples, we determined miRNAs differentially expressed between AKI patients and healthy controls. Statistical and target prediction analysis allowed us to identify a panel of 10 serum miRNAs. This set was further validated, by qRT-PCR, in two independent cohorts of patients with relevant morbi-mortality related to AKI: Intensive Care Units (ICU) and Cardiac Surgery (CS). Statistical correlations with patient clinical parameter were performed. Our results demonstrated that the 10 selected miRNAs (miR-101-3p, miR-127-3p, miR-210-3p, miR-126-3p, miR-26b-5p, miR-29a-3p, miR-146a-5p, miR-27a-3p, miR-93-3p and miR-10a-5p) were diagnostic biomarkers of AKI in ICU patients, exhibiting areas under the curve close to 1 in ROC analysis. Outstandingly, serum miRNAs estimated before CS predicted AKI development later on, thus becoming biomarkers to predict AKI predisposition. Moreover, after surgery, the expression of the miRNAs was modulated days before serum creatinine increased, demonstrating early diagnostic value. In summary, we have identified a set of serum miRNAs as AKI biomarkers useful in clinical practice, since they demonstrate early detection and high diagnostic value and they recognize patients at risk. 相似文献
82.
Schepelmann M Molcan L Uhrova H Zeman M Ellinger I 《Cellular and molecular neurobiology》2011,31(8):1257-1265
Melatonin is involved in blood pressure modulation in rats and humans. Some of the effects of melatonin are presumably mediated
via two G-protein-coupled receptors (MT1 and MT2), but the distribution of MT1 and MT2 in the cardiovascular system remains to be explored comprehensively. We investigated the expression of both the receptors
in the rat aorta on mRNA level by RT-PCR and real time RT-PCR as well as on protein level via western blotting and immunofluorescence
microscopy. We verified MT1 mRNA expression in the rat aorta and demonstrated the absence of MT2 mRNA in this vessel type. MT1 receptors were confirmed also at the protein level, and surprisingly they were preferentially localized to the tunica adventitia.
Since no daily changes in MT1 mRNA expression were detected, we suppose that the circadian changes in circulating melatonin concentrations are sufficient
to mediate circadian effects of melatonin in the aorta. The localization of MT1 in the tunica adventitia suggests an influence of melatonin on vasa vasorum function and signal transduction in the aorta
wall. 相似文献
83.
84.
Ramos JM Costa e Silva ÁM Martins RM Souto FJ 《Memórias do Instituto Oswaldo Cruz》2011,106(5):632-634
Leprosy and hepatitis B virus (HBV) are highly endemic in some regions of the state of Mato Grosso, in central Brazil. The association of leprosy with HBV and hepatitis C virus (HCV) was assessed using a seroprevalence study and 191 leprosy outpatients were included. Demographic data and the clinical classification of leprosy were recorded. Evidence of previous HBV infection was present in 53 patients (27.7%, 95% confidence interval: 21.9-34.5) and two (1%) were HBsAg positive. Five (2.6%) had antibodies to HCV. The prevalence of previous exposure to HBV was higher than expected for an adult population in central Brazil. In contrast, the prevalence of anti-HCV antibodies was not much higher regarding the age range of participants. HBV markers were associated with a higher number of sex partners and the use of injections without proper sterilisation of the syringes. The number of HBV carriers was small, suggesting that there was no increased likelihood of chronification among these patients. 相似文献
85.
There are many different kinds of frameworks for evaluating environmental and sustainability performance at the organizational level (profit or not-for-profit, private or public), sectoral level (e.g. industry, transport, agriculture and tourism), and local, regional or country levels. Despite the diversity of methods and tools to measure sustainable development, indicators are one of the approaches most used. However, these tools do not usually include evaluation of the performance measurement instrument itself. The main objective of this research is to develop a conceptual framework to design and assess the effectiveness of the sustainability indicators themselves. To put the proposed tool into practice, a set of key good-practice factors and meta-performance evaluation indicators is proposed for adoption in a national case study—the national sustainable development indicators system, SIDS Portugal, and the usefulness of this methodology is demonstrated. This approach aims to evaluate how appropriate a set of sustainability indicators is and allow an evaluation of overall performance-monitoring activities and results. Stakeholder involvement is an essential component of the proposed framework. The tool developed could support continuous improvement in the performance of ongoing sustainability indicator initiatives, allowing greater guidance, objectivity and transparency in sustainability assessment processes. 相似文献
86.
Roman Gebauer Daniel Volaík Josef Urban Isabella Brja Nina Elisabeth Nagy Toril Drabls Eldhuset Paal Krokene 《Ecology and evolution》2015,5(21):4989-4998
Predicted increases in the frequency and duration of drought are expected to negatively affect tree vitality, but we know little about how water shortage will influence needle anatomy and thereby the trees’ photosynthetic and hydraulic capacity. In this study, we evaluated anatomical changes in sun and shade needles of 20‐year‐old Norway spruce trees exposed to artificial drought stress. Canopy position was found to be important for needle structure, as sun needles had significantly higher values than shade needles for all anatomical traits (i.e., cross‐sectional needle area, number of tracheids in needle, needle hydraulic conductivity, and tracheid lumen area), except proportion of xylem area per cross‐sectional needle area. In sun needles, drought reduced all trait values by 10–40%, whereas in shade needles, only tracheid maximum diameter was reduced by drought. Due to the relatively weaker response of shade needles than sun needles in drought‐stressed trees, the difference between the two needle types was reduced by 25% in the drought‐stressed trees compared to the control trees. The observed changes in needle anatomy provide new understanding of how Norway spruce adapts to drought stress and may improve predictions of how forests will respond to global climate change. 相似文献
87.
Ígor B. Cursi Roberta Teixeira Silva Isabella Brasil Succi Andréa R. Bernardes-Engemann Rosane Orofino-Costa 《Mycopathologia》2013,175(1-2):75-82
Background
Onychomycosis by Neoscytalidium constitutes chronic infection of the nails, and its frequency has increased in recent decades. Currently, no effective standard treatment exists and literature data remain scarce. This work aimed to conduct a pilot project of combined treatment for this infection.Methods
Thirty patients were divided into three treatment groups: oral terbinafine plus ciclopirox nail lacquer twice a week; ciclopirox nail lacquer twice a week; and ciclopirox nail lacquer 5 days a week, all associated with nail abrasion when required, for 12 months, with 6 months posttreatment follow-up. Clinical and mycological criteria were used for evaluation.Results
Twenty-five patients completed the study. Significant clinical lesion reduction in disease occurred in all three treatment groups: 21 patients (84 %) entered the study with more than 50 % of diseased nail plate, at the end of treatment, and at 6-month follow-up, 84 and 96 %, respectively, presented less than 25 % nail lesion. Negative microscopy was observed in 36 % of the patients at the end of treatment and in 24 % of the patients at 6-month follow-up. At treatment completion (12 months), culture was negative in 21 patients (84 %) and in 18 (72 %) at follow-up. It was not possible to establish any clinical or mycological statistical differences between groups (p > 0.05). Global medical evaluation upon treatment completion revealed that one patient (4 %) presented complete cure, 8 (32 %) presented partial cure, 16 (64 %) presented therapeutic failure. At the end of follow-up period, 6 patients (24 %) were considered to have recurrence/reinfection.Conclusions
The results obtained at the 6-month period of follow-up showed marked improvement (96 % of clinical improvement and 72 % of negative culture) of the patients treated for onychomycosis caused by Neoscytalidium in the three tested groups with no statistical differences between them. Multicentric studies with greater number of patients enrolled are necessary to confirm these results. 相似文献88.
Mammalian DNA ligase III: molecular cloning, chromosomal localization, and expression in spermatocytes undergoing meiotic recombination. 总被引:10,自引:4,他引:10 下载免费PDF全文
89.
Disturbances, elevation, topography and spatial proximity drive vegetation patterns along an altitudinal gradient of a top biodiversity hotspot 总被引:1,自引:0,他引:1
Pedro V. Eisenlohr Luciana F. Alves Luís Carlos Bernacci Maíra C. G. Padgurschi Roseli B. Torres Eduardo M. B. Prata Flavio Antonio M. dos Santos Marco Antônio Assis Eliana Ramos André Luís C. Rochelle Fernando R. Martins Mariana C. R. Campos Fernando Pedroni Maryland Sanchez Larissa S. Pereira Simone A. Vieira José Ataliba M. A. Gomes Jorge Y. Tamashiro Marcos A. S. Scaranello Cora J. Caron Carlos Alfredo Joly 《Biodiversity and Conservation》2013,22(12):2767-2783
The correlation between vegetation patterns (species distribution and richness) and altitudinal variation has been widely reported for tropical forests, thereby providing theoretical basis for biodiversity conservation. However, this relationship may have been oversimplified, as many other factors may influence vegetation patterns, such as disturbances, topography and geographic distance. Considering these other factors, our primary question was: is there a vegetation pattern associated with substantial altitudinal variation (10–1,093 m a.s.l.) in the Atlantic Rainforest—a top hotspot for biodiversity conservation—and, if so, what are the main factors driving this pattern? We addressed this question by sampling 11 1-ha plots, applying multivariate methods, correlations and variance partitioning. The Restinga (forest on sandbanks along the coastal plains of Brazil) and a lowland area that was selectively logged 40 years ago were floristically isolated from the other plots. The maximum species richness (>200 spp. per hectare) occurred at approximately 350 m a.s.l. (submontane forest). Gaps, multiple stemmed trees, average elevation and the standard deviation of the slope significantly affected the vegetation pattern. Spatial proximity also influenced the vegetation pattern as a structuring environmental variable or via dispersal constraints. Our results clarify, for the first time, the key variables that drive species distribution and richness across a large altitudinal range within the Atlantic Rainforest. 相似文献
90.