100 research outputs found

    Modeling Soil Nitrate Accumulation and Leaching in Conventional and Conservation Agriculture Cropping Systems

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    Nitrate is a major groundwater inorganic contaminant that is mainly due to fertilizer leaching. Compost amendment can increase soils’ organic substances and thus promote denitrification in intensively cultivated soils. In this study, two agricultural plots located in the Padana plain (Ferrara, Italy) were monitored and modeled for a period of 2.7 years. One plot was initially amended with 30 t/ha of compost, not tilled, and amended with standard fertilization practices, while the other one was run with standard fertilization and tillage practices. Monitoring was performed continuously via soil water probes (matric potential) and discontinuously via auger core profiles (major nitrogen species) before and after each cropping season. A HYDRUS-1D numerical model was calibrated and validated versus observed matric potential and nitrate, ammonium, and bromide (used as tracers). Model performance was judged satisfactory and the results provided insights on water and nitrogen balances for the two different agricultural practices tested here. While water balance and retention time in the vadose zone were similar in the two plots, nitrate leaching was less pronounced in the plot amended with compost due to a higher denitrification rate. This study provides clear evidence that compost addition and no-tillage (conservation agriculture) can diminish nitrate leaching to groundwater, with respect to standard agricultural practices

    In Search for the Missing Nitrogen: Closing the Budget to Assess the Role of Denitrification in Agricultural Watersheds

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    Although representing a paramount mechanism against nitrogen excess in agricultural landscapes, soil denitrification is still a largely unknown term in nitrogen balances at the watershed scale. In the present work, a comprehensive investigation of nitrogen sources and sinks in agricultural soils and waters was performed with the aim of gaining insights into the relevance of soil denitrification in a highly farmed sub-basin of the Po River delta (Northern Italy). Agricultural statistics, water quality datasets, and results of laboratory experiments targeting nitrogen fluxes in soils were combined to set up a detailed nitrogen budget along the terrestrial–freshwater continuum. The soil nitrogen budget was not closed, with inputs exceeding outputs by 72 kg N·ha−1·year−1, highlighting a potential high risk of nitrate contamination. However, extensive monitoring showed a general scarcity of mineral nitrogen forms in both shallow aquifers and soils. The present study confirmed the importance of denitrification, representing ~37% of the total nitrogen inputs, as the leading process of nitrate removal in heavily fertilized fine-texture soils prone to waterlogged conditions

    Sensitivity to selected contaminants in a biological early warning system using 'Anodonta woodiana' (Mollusca)

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    Several early warning systems for the monitoring of water quality are based on the assessment of valve opening/closing in bivalves. Tests were conducted to assess the sensitivity of the mussel Anodonta woodiana , installed on the Mosselmonitor, to seven contaminants and evaluate the usefulness of these sensors for detecting pollution events in the Po River (Italy). Mussels were exposed for 30 min to increasing concentrations of chromium (range 0.01–5 mg/L); arsenic (range 0.05–2.5 mg/L); sodium dodecyl sulphate SDS (range 0.25–50 mg/L); phenol (range 0.1–100 mg/L); oxadiazon (range 0.001–5 mg/L); trichloroethylene (range 0.01–100 mg/L); and crude oil (range 0.5–50 mg/L). Treatment with the highest concentration of SDS elicited two types of alarm response. In a second set of tests, the bivalves were exposed for 6 h to a selected concentration of each chemical. Only SDS led to a dramatic alteration of valve opening, resulting in alarms. This system would have limited applications for monitoring drinking water influent. Keywords: bioindication, mussels, valve movement, toxicity test, toxic substance

    Gemcitabine-based doublets versus single-agent therapy for elderly patients with advanced nonsmall cell lung cancer: a Literature-based Meta-analysis.

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    Although platinum-based combinations are considered the best option of care for patients with advanced nonsmall cell lung cancer (NSCLC), single-agent therapy is the preferred treatment for older patients. Since the late 1990s, various combinations of third-generation agents (gemcitabine [G], vinorel- bine, docetaxel, and paclitaxel) have been tested, yielding contradictory results. The authors of this report performed a literature-based meta-analysis to assess the efficacy and tolerability of G-based doublets compared with single-agent chemotherapy for elderly patients with NSCLC. METHODS: Data from all published, randomized, phase 3 trials that compared a G-based doublet with a third-generation single agent in elderly patients were collected from electronic databases (Medline and the Cochrane Central Register of Controlled Trials), relevant reference lists, and abstract books. Pooled odds ratios (ORs) were calculated for the 1-year survival rate, the overall response rate (ORR), and grade 3 and 4 toxicities. RESULTS: Four eligible trials (1436 patients) were selected from 442 studies that initially were identified. A significant difference in ORR favoring G-based doublets over single agents was observed (OR, 0.65; 95% confidence interval [95% CI], 0.51-0.82 [P<.001]), whereas the trend toward an improved 1-year survival rate was not significant (OR, 0.78; 95% CI, 0.57-1.06 [P¼.169]). Grade 3 and 4 toxicities did not differ significantly except for thrombocytopenia (OR, 1.76; 95% CI, 1.12-2.76 [P¼.014]). CONCLUSIONS: G-based doublets appeared to be effective and feasible compared with single agents in the treatment of elderly patients with advanced NSCLC who were not suitable for full-dose, platinum-based chemotherapy. Further prospective, elderly specific, phase 3 trials will be necessary

    Quality of life in alopecia areata: A disease-specific questionnaire

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    Background Alopecia areata (AA) is an autoimmune disease affecting about 2% of the population, which has a considerable impact on quality of life (QoL). There are no disease-specific questionnaires to assess QoL in patients suffering from AA. Objective To validate a new disease-specific questionnaire for AA, named AA-QLI, and to compare the consequent Quality of Life Index (QLI) with the commonly known Dermatology Life Quality Index (DLQI) to verify if it can provide a more comprehensive tool for patients. Methods A total of 50 patients affected by AA were administered both the AA-QLI, created by us, and the well-known DLQI. With the aim to detect suitable QLI, we propose to use two multivariate analyses: a principal component analysis approach on the data collected with both questionnaires to compare their capability to measure the QoL; a structural equation modelling on our AA-QLI to identify which category of symptoms mostly affects the QoL. Results The scores of both the questionnaires are quite close, except for a few cases. Statistical analysis shows a higher specificity of the AA-QLI for evaluating QoL. Among the three areas in which AA-QLI is divided, 'Relationship' has a major impact on the QLI, followed by 'Subjective symptoms'; 'Objective signs' has a lower weight on the QLI. Conclusion AA-QLI is a good instrument to evaluate the real impact of AA on QoL. It can be helpful both for the physician and for the patient. © 2012 European Academy of Dermatology and Venereology

    Early magnesium reduction in advanced colorectal cancer patients treated with cetuximab plus irinotecan as predictive factor of efficacy and outcome

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    Introduction: Magnesium plays a role in a large number of cellular metabolic reactions. Cetuximab is able to induce hypomagnesemia by interfering with magnesium (Mg2+) transport in the kidney.We designed this trial to investigate if Mg2+ serum level modifications may be related with clinical response andoutcome in advancedcolorectal cancer patients during treatment with cetuximab plus irinotecan. Experimental Design: Sixty-eight heavily pretreatedmetastatic colorectal cancer patients were evaluatedfor Mg2+ serum levels at the following time points: before; 6 hours; and1, 7, 14, 21, 50, and92 days after the start of treatment. Results: Basal Mg2+ median levels were significantly decreased just 7 days after the first anticancer infusion and progressively decreased from the 7th day onward, reaching the highest significance at the last time point (P < 0.0001).Twenty-five patients showeda reduction in median Mg2+ circulating levels of at least 20% within the 3rdweek after the first infusion. Patients with this reduction showed a response rate of 64.0% versus 25.6% in the nonreduced Mg2+ group. The median time to progression was 6.0 versus 3.6 months in the reduced Mg2+ group andin that without reduction, respectively (P < 0.0001). Overall survival was longer in patients with Mg2+ reduction than in those without (10.7 versus 8.9 months). Conclusions: Our results confirm that cetuximab treatment may induce a reduction of Mg2+ circulating levels andoffer the first evidence that Mg2+ reduction may represent a new predictive factor of efficacy in advanced colorectal cancer patients treated with cetuximab plus irinoteca

    A fully automated micro‑CT deep learning approach for precision preclinical investigation of lung fibrosis progression and response to therapy

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    : Micro-computed tomography (µCT)-based imaging plays a key role in monitoring disease progression and response to candidate drugs in various animal models of human disease, but manual image processing is still highly time-consuming and prone to operator bias. Focusing on an established mouse model of bleomycin (BLM)-induced lung fibrosis we document, here, the ability of a fully automated deep-learning (DL)-based model to improve and speed-up lung segmentation and the precise measurement of morphological and functional biomarkers in both the whole lung and in individual lobes. µCT-DL whose results were overall highly consistent with those of more conventional, especially histological, analyses, allowed to cut down by approximately 45-fold the time required to analyze the entire dataset and to longitudinally follow fibrosis evolution and response to the human-use-approved drug Nintedanib, using both inspiratory and expiratory μCT. Particularly significant advantages of this µCT-DL approach, are: (i) its reduced experimental variability, due to the fact that each animal acts as its own control and the measured, operator bias-free biomarkers can be quantitatively compared across experiments; (ii) its ability to monitor longitudinally the spatial distribution of fibrotic lesions, thus eliminating potential confounding effects associated with the more severe fibrosis observed in the apical region of the left lung and the compensatory effects taking place in the right lung; (iii) the animal sparing afforded by its non-invasive nature and high reliability; and (iv) the fact that it can be integrated into different drug discovery pipelines with a substantial increase in both the speed and robustness of the evaluation of new candidate drugs. The µCT-DL approach thus lends itself as a powerful new tool for the precision preclinical monitoring of BLM-induced lung fibrosis and other disease models as well. Its ease of operation and use of standard imaging instrumentation make it easily transferable to other laboratories and to other experimental settings, including clinical diagnostic applications

    Prevention of quercetin precipitation in red wines: a promising enzymatic solution

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    Flavonols are known for causing undesirable deposits in both red and white wines. Among flavonols, quercetin is widely considered the principal factor determining this phenomenon. One of the most accredited hypotheses claims that glycosylated derivatives of quercetin undergo hydrolysis of the glycosylic bond during the fermentation and the wine ageing, releasing quercetin aglycone, which is much less soluble in water solution and causes the precipitation. Our work describes the dynamics of quercetin-derived deposition in Chianti wines and purposes a new method, based on the enzymatic quercetin glycoside hydrolysis of the glycosidic bond, to prevent the unpleasant deposit formation during the wine ageing. In our study, forty-four monovarietal wines obtained from 7 different Italian grape varieties were compared in the content of total quercetin-3-glycosides (rutin, quercetin-3-glucuronide, quercetin-3-glucoside) and quercetin aglycone. The data confirmed the literature revealing Sangiovese as the richest in quercetin. We tested then, in a Sangiovese wine, four fining agents (PVPP, PVPP/PVI, bentonite and a vegetal protein) for quercetin removal, showing that only the PVPP had a modest aglycone removal activity. Then, the kinetics of deposit formation was studied in three Chianti wines which differed in the initial content of quercetin aglycone. This investigation highlighted that the chemical equilibrium of quercetin changes over time as the turbidity slowly increases, as previously documented. The comparison of the three dynamics also permitted us to conclude that different wines show a different ability to keep in solution quercetin. Finally, a new approach for deposit prevention was studied by a precocious Chianti wine treatment with a pectolytic enzyme having secondary glycosidase activity. This enzyme significantly accelerated the hydrolysis of glycosylated quercetins into their aglycone, which could enhance the deposition before bottling, without serious wine colour depletion. Our study represents the first evidence of the promising potential of using the pectolytic enzyme with secondary glycosidase activity to prevent quercetin deposit during Chianti ageing, in a way that is compatible with organic wine production

    Direct-acting antivirals and hepatocellular carcinoma in chronic hepatitis C: A few lights and many shadows

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    With the introduction of direct-acting antiviral agents (DAA), the rate of sustained virological response (SVR) in the treatment of hepatitis C virus (HCV) has radically improved to over 95%. Robust scientific evidence supports a beneficial role of SVR after interferon therapy in the progression of cirrhosis, resulting in a decreased incidence of hepatocellular carcinoma (HCC). However, a debate on the impact of DAAs on the development of HCC is ongoing. This review aimed to analyse the scientific literature regarding the risk of HCC in terms of its recurrence and occurrence after the use of DAAs to eradicate HCV infection. Among 11 studies examining HCC occurrence, the de novo incidence rate ranged from 0 to 7.4% (maximum follow-up: 18 mo). Among 18 studies regarding HCC recurrence, the rate ranged from 0 to 54.4% (maximum "not well-defined" followup: 32 mo). This review highlights the major difficulties in interpreting data and reconciling the results of the included studies. These difficulties include heterogeneous cohorts, potential misclassifications of HCC prior to DAA therapy, the absence of an adequate control group, short follow-up times and different kinds of follow-up. Moreover, no clinical feature-based scoring system accounts for the molecular characteristics and pathobiology of the tumours. Nonetheless, this review does not suggest that there is a higher rate of de novo HCC occurrence or recurrence after DAA therapy in patients with previous HCV infection. \ua9 2018 The Author(s). Published by Baishideng Publishing Group Inc. All rights reserved
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