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101.
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Beatriz Martín-Fernández Alfonso Rubio-Navarro Isabel Cortegano Sandra Ballesteros Mario Alía Pablo Cannata-Ortiz Elena Olivares-álvaro Jesús Egido Belén de Andrés María Luisa Gaspar Natalia de las Heras Vicente Lahera Juan Antonio Moreno 《PloS one》2016,11(1)
We aimed to evaluate macrophages heterogeneity and structural, functional and inflammatory alterations in rat kidney by aldosterone + salt administration. The effects of treatment with spironolactone on above parameters were also analyzed. Male Wistar rats received aldosterone (1 mgkg-1d-1) + 1% NaCl for 3 weeks. Half of the animals were treated with spironolactone (200 mg kg-1d-1). Systolic and diastolic blood pressures were elevated (p<0.05) in aldosterone + salt–treated rats. Relative kidney weight, collagen content, fibronectin, macrophage infiltrate, CTGF, Col I, MMP2, TNF-α, CD68, Arg2, and SGK-1 were increased (p<0.05) in aldosterone + salt–treated rats, being reduced by spironolactone (p<0.05). Increased iNOS and IFN-γ mRNA gene expression (M1 macrophage markers) was observed in aldosterone + salt rats, whereas no significant differences were observed in IL-10 and gene ArgI mRNA expression or ED2 protein content (M2 macrophage markers). All the observed changes were blocked with spironolactone treatment. Macrophage depletion with liposomal clodronate reduced macrophage influx and inflammatory M1 markers (INF-γ or iNOS), whereas interstitial fibrosis was only partially reduced after this intervention, in aldosterone plus salt-treated rats. In conclusion, aldosterone + salt administration mediates inflammatory M1 macrophage phenotype and increased fibrosis throughout mineralocorticoid receptors activation. 相似文献
104.
Tim van der Weijde Andres F. Torres Oene Dolstra Annemarie Dechesne Richard G. F. Visser Luisa M. Trindade 《Bioenergy Research》2016,9(1):146-156
Lignin is a key factor limiting saccharification of lignocellulosic feedstocks. In this comparative study, various lignin methods—including acetyl bromide lignin (ABL), acid detergent lignin (ADL), Klason lignin (KL), and modified ADL and KL determination methods—were evaluated for their potential to assess saccharification efficiency. Six diverse accessions of the bioenergy crop miscanthus were used for this analysis, which included accessions of Miscanthus sinensis, Miscanthus sacchariflorus, and hybrid species. Accessions showed large variation in lignin content. Lignin estimates were different between methods, but (highly) correlated to each other (0.54?≤?r?≤?0.94). The strength of negative correlations to saccharification efficiency following either alkaline or dilute acid pretreatment differed between lignin estimates. The strongest and most consistent correlations (?0.48?≤?r?≤??0.85) were obtained with a modified Klason lignin method. This method is suitable for high throughput analysis and was the most effective in detecting differences in lignin content (p?<?0.001) between accessions. 相似文献
105.
Fatiha Tabet Luisa F. Cuesta Torres Kwok Leung Ong Sudichhya Shrestha Sébastien A. Choteau Philip J. Barter Peter Clifton Kerry-Anne Rye 《PloS one》2016,11(3)
Background and Aims
microRNAs (miRNAs) are small, endogenous non-coding RNAs that regulate metabolic processes, including obesity. The levels of circulating miRNAs are affected by metabolic changes in obesity, as well as in diet-induced weight loss. Circulating miRNAs are transported by high-density lipoproteins (HDL) but the regulation of HDL-associated miRNAs after diet-induced weight loss has not been studied. We aim to determine if HDL-associated miR-16, miR-17, miR-126, miR-222 and miR-223 levels are altered by diet-induced weight loss in overweight and obese males.Methods
HDL were isolated from 47 subjects following 12 weeks weight loss comparing a high protein diet (HP, 30% of energy) with a normal protein diet (NP, 20% of energy). HDL-associated miRNAs (miR-16, miR-17, miR-126, miR-222 and miR-223) at baseline and after 12 weeks of weight loss were quantified by TaqMan miRNA assays. HDL particle sizes were determined by non-denaturing polyacrylamide gradient gel electrophoresis. Serum concentrations of human HDL constituents were measured immunoturbidometrically or enzymatically.Results
miR-16, miR-17, miR-126, miR-222 and miR-223 were present on HDL from overweight and obese subjects at baseline and after 12 weeks of the HP and NP weight loss diets. The HP diet induced a significant decrease in HDL-associated miR-223 levels (p = 0.015), which positively correlated with changes in body weight (r = 0.488, p = 0.032). Changes in miR-223 levels were not associated to changes in HDL composition or size.Conclusion
HDL-associated miR-223 levels are significantly decreased after HP diet-induced weight loss in overweight and obese males. This is the first study reporting changes in HDL-associated miRNA levels with diet-induced weight loss. 相似文献106.
Barbara Leoni Clelia Luisa Marti Elena Forasacco Matteo Mattavelli Valentina Soler Pietro Fumagalli Jörg Imberger Simone Rezzonico Letizia Garibaldi 《Limnology》2016,17(2):175-182
Lake Monger (Perth, Western Australia) is a highly eutrophic lake, characterised by very low species richness of macrophytes with the dominance of Potamogeton crispus. Mesocosm experiments were performed using water and plants collected from the lake to determine the effects of vegetation decay on the phosphorus (P) concentrations in the overlying waters. After 2 weeks of experimental incubation of mesocosms with and without re-oxygenation, P concentrations in the water column were significantly higher, showing a quite similar effect of P. crispus on the phosphorus release in different mesocosms. The results of our study provide clear evidence that the P concentrations in overlying waters mainly depend upon the plant P content and developmental stage. Although many sources contribute to the nutrient load of Lake Monger, macrophyte harvesting, prior to its senescence, might constitute a significant in-lake measure for reducing the internal P load. 相似文献
107.
The formation of titan cells in Cryptococcus neoformans depends on the mouse strain and correlates with induction of Th2‐type responses 下载免费PDF全文
Irene García‐Barbazán Nuria Trevijano‐Contador Cristina Rueda Belén de Andrés Raquel Pérez‐Tavárez Inés Herrero‐Fernández María Luisa Gaspar Oscar Zaragoza 《Cellular microbiology》2016,18(1):111-124
Cryptococcus neoformans is a pathogenic yeast that can form titan cells in the lungs, which are fungal cells of abnormal enlarged size. Little is known about the factors that trigger titan cells. In particular, it is not known how the host environment influences this transition. In this work, we describe the formation of titan cells in two mouse strains, CD1 and C57BL/6J. We found that the proportion of C. neoformans titan cells was significantly higher in C57BL/6J mice than in CD1. This higher proportion of titan cells was associated with a higher dissemination of the yeasts to the brain. Histology sections demonstrated eosinophilia in infected animals, although it was significantly lower in the CD1 mice which presented infiltration of lymphocytes. Both mouse strains presented infiltration of granulocytes, but the amount of eosinophils was higher in C57BL/6J. CD1 mice showed a significant accumulation of IFN‐γ, TNF‐α and IL17, while C57BL/BL mice had an increase in the anti‐inflammatory cytokine IL‐4. IgM antibodies to the polysaccharide capsule and total IgE were more abundant in the sera from C57BL/6J, confirming that these animals present a Th2‐type response. We conclude that titan cell formation in C. neoformans depends, not only on microbe factors, but also on the host environment. 相似文献
108.
Carolina Vergara Cid María Julieta Salazar Andrés Blanco María Luisa Pignata 《International journal of phytoremediation》2016,18(9):908-917
Polluted agricultural soils are a serious problem for food safety, with phytoremediation being the most favorable alternative from the environmental perspective. However, this methodology is generally time-consuming and requires the cessation of agriculture. Therefore, the purpose of this study was to evaluate two potential phytoextractor plants (the native species Bidens pilosa and Tagetes minuta) co-cropped with lettuce growing on agricultural lead-polluted soils. The concentrations of Pb, as well as of other metals, were investigated in the phytoextractors, crop species, and in soils, with the potential risk to the health of consumers being estimated. The soil parameters pH, EC, organic matter percentage and bioavailable lead showed a direct relationship with the accumulation of Pb in roots. In addition, the concentration of Pb in roots of native species was closely related to Fe (B. pilosa, r = 0.81; T. minuta r = 0.75), Cu (T. minuta, r = 0.93), Mn (B. pilosa, r = 0.89) and Zn (B. pilosa, r = 0.91; T. minuta, r = 0.91). Our results indicate that the interaction between rhizospheres increased the phytoextraction of lead, which was accompanied by an increase in the biomass of the phytoextractor species. However, the consumption of lettuce still revealed a toxicological risk from Pb in all treatments. 相似文献
109.
Eva Borràs Ester Cantó Meena Choi Luisa Maria Villar José Carlos álvarez-Cerme?o Cristina Chiva Xavier Montalban Olga Vitek Manuel Comabella Eduard Sabidó 《Molecular & cellular proteomics : MCP》2016,15(1):318-328
Multiple sclerosis is an inflammatory, demyelinating, and neurodegenerative disease of the central nervous system. In most patients, the disease initiates with an episode of neurological disturbance referred to as clinically isolated syndrome, but not all patients with this syndrome develop multiple sclerosis over time, and currently, there is no clinical test that can conclusively establish whether a patient with a clinically isolated syndrome will eventually develop clinically defined multiple sclerosis. Here, we took advantage of the capabilities of targeted mass spectrometry to establish a diagnostic molecular classifier with high sensitivity and specificity able to differentiate between clinically isolated syndrome patients with a high and a low risk of developing multiple sclerosis. Based on the combination of abundances of proteins chitinase 3-like 1 and ala-β-his-dipeptidase in cerebrospinal fluid, we built a statistical model able to assign to each patient a precise probability of conversion to clinically defined multiple sclerosis. Our results are of special relevance for patients affected by multiple sclerosis as early treatment can prevent brain damage and slow down the disease progression.Multiple sclerosis is an inflammatory, demyelinating, and neurodegenerative disease of the central nervous system, and although the etiology of the disease is not fully understood, it is probably caused by the interaction of a complex genetic architecture and environmental factors. Multiple sclerosis affects over 2 million people worldwide, and it is typically diagnosed between ages 20 and 40, thus making a significant impact on public health and its economy (1).In most patients, the disease initiates with an episode of neurological disturbance referred to as clinically isolated syndrome. However, not all patients with this syndrome develop multiple sclerosis over time (2), and currently, the magnetic resonance imaging (MRI) abnormalities and the presence of IgG oligoclonal bands in cerebrospinal fluid (CSF) are used as predictors for later conversion to clinically definite multiple sclerosis (CDMS)1 (3–5). Although such abnormalities are considered important factors that influence the likelihood of developing CDMS, there is currently no clinical test that can conclusively establish whether a patient with a clinically isolated syndrome will eventually develop CDMS.The lack of diagnostic and prognostic biomarkers is a common problem for many diseases lacking a complete etiology, which is the case for most neurological disorders related to the central nervous system such as Parkinson''s and Alzheimer''s diseases, schizophrenia, and multiple sclerosis. In the particular case of multiple sclerosis, early treatment of patients with a clinically isolated syndrome can prevent brain damage and slow down the disease progression (6). Therefore, the availability of a diagnostic test in the initial stages of the disease is not only desirable but also of extreme relevance to attenuate the degenerative effects of the disease.Biomarker validation has traditionally been dominated by enzyme linked immuno-sorbent assays (ELISA), but recent advances in proteomics techniques have enabled the measurement of a subset of selected proteins over a large dynamic concentration range in multiple samples. Targeted mass spectrometry has thus become the method of choice when quantifying simultaneously a panel of proteins across many different biological samples (7–9). In particular, selected reaction monitoring (SRM) is the gold standard targeted mass spectrometry method for protein quantification due to its high precision, reliability, and throughput (10–13). This targeted mass spectrometry method is performed on triple quadrupole instruments, in which a predefined peptide precursor ion is first isolated, and then selected fragment ions arising from its collisional dissociation are measured over time. Each pair of precursor and fragment ion is called a transition, and multiple transitions can be coordinately measured and used to conclusively identify and quantify a peptide in a clinical complex sample.In a previous study, we used a screening mass spectrometric approach to discover potential markers for multiple sclerosis conversion in patients that initially presented a clinical isolated syndrome (14). In that discovery phase, quantitative mass spectrometry with iTRAQ labeling was used to measure protein abundances in pooled CSF samples from patients presenting a clinical isolated syndrome that either remained normal (CIS) or had eventually converted to clinically definite multiple sclerosis (CDMS) (n = 60). In the initial screening, several proteins exhibited significant differences in abundance when comparing these two groups of patients. The abundance change in one of the altered proteins, chitinase 3-like 1 (CH3L1), was confirmed by ELISA in CSF of individual patients, whereas for others, such as semaphorin 7A (SEM7A) and ala-β-his-dipeptidase (CNDP1), their abundance changes were confirmed by targeted mass spectrometry in follow-up studies with independent cohorts (15). Moreover, the levels of CH3L1 were associated with brain MRI abnormalities and disability progression during the follow-up period, as well as with shorter time to conversion to clinically definite multiple sclerosis (14).We now set out to establish a diagnostic protein classifier with high sensitivity and specificity able to differentiate between patients with a clinically isolated syndrome that have either a high or a low risk of developing clinically definite multiple sclerosis over time. For this purpose, CSF samples from an independent patient cohort from the one used in the discovery study were collected, and a set of preselected protein biomarker candidates were systematically quantified by targeted mass spectrometry (SRM) and evaluated for their classification power. Out of this study, we established a protein classifier based on the combination of abundances of proteins chitinase 3-like 1 and ala-β-his-dipeptidase, which is able to differentiate with high sensitivity and specificity between patients with a clinically isolated syndrome that have either a high or low risk of developing clinically definite multiple sclerosis. Moreover, the statistical model built around this protein classifier enables clinicians to easily assign to each patient a precise probability of conversion to clinically definite multiple sclerosis (Fig. 1).Open in a separate windowFig. 1.General workflow used in the present study. Initially, protein candidates identified in our previous discovery studies—together with several proteins described by other groups—were selected and quantified by targeted mass spectrometry (SRM) in a relatively large cohort individual patients. Protein quantities were then evaluated by their capability of classifying patients with clinical isolated syndrome, and thus, the best prognostic protein combination was identified. 相似文献
110.
Discovery of A-type procyanidin dimers in yellow raspberries by untargeted metabolomics and correlation based data analysis 总被引:1,自引:0,他引:1
Elisabete Carvalho Pietro Franceschi Antje Feller Lorena Herrera Luisa Palmieri Panagiotis Arapitsas Samantha Riccadonna Stefan Martens 《Metabolomics : Official journal of the Metabolomic Society》2016,12(9):144