Soil organic matter humification under different tillage managements evaluated by Laser Induced Fluorescence (LIF) and C/N ratio

AbstractIn this work is presented the use of the C/N ratio and the Laser Induced Fluorescence (LIF) spectroscopy for determining the humification of soil organic matter (SOM) in an Oxisol under three different long-term tillage managements (no-tillage (NT), reduced tillage (RT) and conventional tillage (CT)). Humification of SOM was evaluated in the soil and its fractions (clay<2μm, silt 2–20μm, sand 20–1000μm). The obtained results show that lower SOM humification was observed in soil under NT, mainly at the surface (0–5cm). In CT, SOM humification values maintained constant for all investigated depths (0–5, 5–10, 10–15 and 15–20cm). Also, clay was the soil fraction that exhibited the lesser humification of SOM. Based on the obtained results it can be said that NT favors the accumulation of SOM on its surface, increasing aggregate stability and presenting samples with lower humification indexes. These results indicate a larger availability of nutrients for the plants in this management

Characterization of oil shale residue and rejects from irati formation by electron paramagnetic resonance

In this study, sedimentary organic matter of oil shale rejects, calschist, shale fine and the so called retorted shale from Irati formation was characterized. EPR was used to analyse the samples regarding loss of signal in g = 2.003 associated to the organic free radical with the calcined samples and washing with hydrogen peroxide. The radical signal was detected in all samples, however, for the calschist and shale fine samples another signal was identified at g = 2.000 which disappeared when the sample was heated at 400 ºC. Hydrogen peroxide washing was also performed and it was noted that after washing the signal appeared around g = 2.000 for all samples, including retorted shale, which might be due to the quartz E1 defect

Global Retinoblastoma Presentation and Analysis by National Income Level

Importance: Early diagnosis of retinoblastoma, the most common intraocular cancer, can save both a child's life and vision. However, anecdotal evidence suggests that many children across the world are diagnosed late. To our knowledge, the clinical presentation of retinoblastoma has never been assessed on a global scale. Objectives: To report the retinoblastoma stage at diagnosis in patients across the world during a single year, to investigate associations between clinical variables and national income level, and to investigate risk factors for advanced disease at diagnosis. Design, Setting, and Participants: A total of 278 retinoblastoma treatment centers were recruited from June 2017 through December 2018 to participate in a cross-sectional analysis of treatment-naive patients with retinoblastoma who were diagnosed in 2017. Main Outcomes and Measures: Age at presentation, proportion of familial history of retinoblastoma, and tumor stage and metastasis. Results: The cohort included 4351 new patients from 153 countries; the median age at diagnosis was 30.5 (interquartile range, 18.3-45.9) months, and 1976 patients (45.4) were female. Most patients (n = 3685 84.7%) were from low-and middle-income countries (LMICs). Globally, the most common indication for referral was leukocoria (n = 2638 62.8%), followed by strabismus (n = 429 10.2%) and proptosis (n = 309 7.4%). Patients from high-income countries (HICs) were diagnosed at a median age of 14.1 months, with 656 of 666 (98.5%) patients having intraocular retinoblastoma and 2 (0.3%) having metastasis. Patients from low-income countries were diagnosed at a median age of 30.5 months, with 256 of 521 (49.1%) having extraocular retinoblastoma and 94 of 498 (18.9%) having metastasis. Lower national income level was associated with older presentation age, higher proportion of locally advanced disease and distant metastasis, and smaller proportion of familial history of retinoblastoma. Advanced disease at diagnosis was more common in LMICs even after adjusting for age (odds ratio for low-income countries vs upper-middle-income countries and HICs, 17.92 95% CI, 12.94-24.80, and for lower-middle-income countries vs upper-middle-income countries and HICs, 5.74 95% CI, 4.30-7.68). Conclusions and Relevance: This study is estimated to have included more than half of all new retinoblastoma cases worldwide in 2017. Children from LMICs, where the main global retinoblastoma burden lies, presented at an older age with more advanced disease and demonstrated a smaller proportion of familial history of retinoblastoma, likely because many do not reach a childbearing age. Given that retinoblastoma is curable, these data are concerning and mandate intervention at national and international levels. Further studies are needed to investigate factors, other than age at presentation, that may be associated with advanced disease in LMICs. © 2020 American Medical Association. All rights reserved

Radiation attenuation properties based on the quantification of soil components using the Rietveld Method

We propose the use of X-ray diffraction associated with Rietveld Method (RM-XRD) for soil components quantification aiming at evaluating photon attenuation parameters (total and partial attenuation coefficients (µ), effective atomic number (Zeff), effective electron density (Nel) and cross-sections per atom (σa) and per electron (σe)). The XCOM computer code was utilized to calculate these parameters. The X-ray fluorescence spectroscopy (XRF) technique was used as reference for the quantification of soil components. Good agreement was found between XRF and RM-XRD for photons ranging from medium to high energies. Photons of low energy (<0.1 MeV) presented slight differences between these two methods. Keywords: X-ray diffraction, X-ray fluorescence spectroscopy, XCOM computer code, Mass attenuation coefficient, Cross-section

In vitro evaluation of the biological activity of Lebanase medicinal plants extracts against herpes simplex virus type 1.

Medicinal plants extracts are interesting novel drugs for use as antimicrobial and antiviral agents. In this study we investigate the in vitro antiviral activity of eight ethanol medicinal plant extracts against Herpes simplex virus (HSV-1) infection on monkey kidney cells. Acyclovir, an antiviral agent currently applied for treatment of herpes virus type 1 infection, was used to compare the plant extracts therapeutic activity. The inhibitory concentrations (IC50) were determined for eight medicinal plants extracts obtained from the following plants: Calamintha origanifolia, Satureja thymbra, Prangos aspurela, Sidiritis Perfoliata, Aspurela glomerata, Erythreae Centaurium, Hyssopus officinalis and Salvia accetabulosa. Cytotoxicity was evaluated by MTT assay in Vero cells. The selective index (SI) of these medicinal plant extracts was used to prove the therapeutic activity. We found that C. origanifolia and S.thymbra extracts have the highest selective index (SI) in our data and are therefore potentially be used for treatment of HSV-1 disease

Microfluidic/HPLC combination to study carnosine protective activity on challenged human microglia: Focus on oxidative stress and energy metabolism

Carnosine (beta-alanyl-L-histidine) is a naturally occurring endogenous peptide widely distributed in excitable tissues such as the brain. This dipeptide possesses well-demonstrated antioxidant, anti-inflammatory, and antiaggregation properties, and it may be useful for treatment of pathologies characterized by oxidative stress and energy unbalance such as depression and Alzheimer's disease (AD). Microglia, the brain-resident macrophages, are involved in different physiological brain activities such synaptic plasticity and neurogenesis, but their dysregulation has been linked to the pathogenesis of numerous diseases. In AD brain, the activation of microglia towards a pro-oxidant and pro-inflammatory phenotype has found in an early phase of cognitive decline, reason why new pharmacological targets related to microglia activation are of great importance to develop innovative therapeutic strategies. In particular, microglia represent a common model of lipopolysaccharides (LPS)-induced activation to identify novel pharmacological targets for depression and AD and numerous studies have linked the impairment of energy metabolism, including ATP dyshomeostasis, to the onset of depressive episodes. In the present study, we first investigated the toxic potential of LPS + ATP in the absence or presence of carnosine. Our studies were carried out on human microglia (HMC3 cell line) in which LPS + ATP combination has shown the ability to promote cell death, oxidative stress, and inflammation. Additionally, to shed more light on the molecular mechanisms underlying the protective effect of carnosine, its ability to modulate reactive oxygen species production and the variation of parameters representative of cellular energy metabolism was evaluated by microchip electrophoresis coupled to laser-induced fluorescence and high performance liquid chromatography, respectively. In our experimental conditions, carnosine prevented LPS + ATP-induced cell death and oxidative stress, also completely restoring basal energy metabolism in human HMC3 microglia. Our results suggest a therapeutic potential of carnosine as a new pharmacological tool in the context of multifactorial disorders characterize by neuroinflammatory phenomena including depression and AD

Characterization of Carnosine Effect on Human Microglial Cells under Basal Conditions

The activity of microglia is fundamental for the regulation of numerous physiological processes including brain development, synaptic plasticity, and neurogenesis, and its deviation from homeostasis can lead to pathological conditions, including numerous neurodegenerative disorders. Carnosine is a naturally occurring molecule with well-characterized antioxidant and anti-inflammatory activities, able to modulate the response and polarization of immune cells and ameliorate their cellular energy metabolism. The better understanding of microglia characteristics under basal physiological conditions, as well as the possible modulation of the mechanisms related to its response to environmental challenges and/or pro-inflammatory/pro-oxidant stimuli, are of utmost importance for the development of therapeutic strategies. In the present study, we assessed the activity of carnosine on human HMC3 microglial cells, first investigating the effects of increasing concentrations of carnosine on cell viability. When used at a concentration of 20 mM, carnosine led to a decrease of cell viability, paralleled by gene expression increase and decrease, respectively, of interleukin 6 and heme oxygenase 1. When using the maximal non-toxic concentration (10 mM), carnosine decreased nitric oxide bioavailability, with no changes in the intracellular levels of superoxide ion. The characterization of energy metabolism of HMC3 microglial cells under basal conditions, never reported before, demonstrated that it is mainly based on mitochondrial oxidative metabolism, paralleled by a high rate of biosynthetic reactions. The exposure of HMC3 cells to carnosine seems to ameliorate microglia energy state, as indicated by the increase in the adenosine triphosphate/adenosine diphosphate (ATP/ADP) ratio and energy charge potential. The improvement of cell energy metabolism mediated by 10 mM carnosine could represent a useful protective weapon in the case of human microglia undergoing stressing conditions