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关键词： Hyperspectral   Spectroscopy   Carotenoid content   Chlorophyll content   Water content   LUT   PROSAIL RTM  

摘要： Information about pigment and water contents provides comprehensive insights for evaluating photosynthetic potential and activity of agricultural crops. In this study, we present the concept of using spectral integral ratios (SIR) to retrieve three biochemical traits, namely chlorophyll a and b (C-ab), carotenoids (C-cx), and water (C-w) content, simultaneously from hyperspectral measurements in the wavelength range 460-1100 nm. The SIR concept is based on automatic separation of respective absorption features through local peak and intercept analysis between log-transformed reflectance and convex hulls. The algorithm was tested on two synthetically established databases using a physiologically constrained look-up-table (LUT) generated by (i) the leaf optical properties model PROSPECT and (ii) the canopy radiative transfer model (RTM) PROSAIL. LUT constraints were realized based on natural C-cx-C-ab relations and green peak locations identified in the leaf optical database ANGERS. Linear regression between obtained SIRs and model parameters resulted in coefficients of determi-nation (R-2) of 0.66 (i and ii) for C-cx, R-2 = 0.85 (i) and 0.53 (ii) for C-ab, and R-2 = 0.97 (i) and 0.67 (ii) for C-w, respectively. Using the model established from the PROSPECT LUT, leaf level validation was carried out based on ANGERS data with reasonable results both in terms of goodness of fit and root mean square error (RMSE) (C-cx: R-2 = 0.86, RMSE = 2.1 mu g cm(-2);C-ab: R-2 = 0.67, RMSE = 12.5 mu g cm(-2);C-w: R-2 = 0.89, RMSE = 0.007 cm). The algorithm was applied to airborne spectrometric HyMap data acquired on 12th July 2003 in Barrax, Spain and to AVIRIS-NG data recorded on 2nd July 2018 southwest of Munich, Germany. Mapping of the SIR results as multiband images (3-segment SIR) allows for intuitive visualization of dominant absorptions with respect to the three considered biochemical variables. Barrax in situ validation using linear regression models derived from PROSAIL LUT s

关键词： reflux   airway   laryngopharyngeal reflux (LPR)   extraesophageal reflux (EER)   pepsin   cough  

摘要： Airway reflux is implicated in the pathophysiology of a wide range of adult and pediatric upper and lower airway diseases. However, the diagnosis of proximal reflux-associated disease remains challenging due to evolving clinical criteria and institutional and regional variances in diagnostic practices. Evidence suggests that nonacidic contents of reflux may serve as both pathologic mediators of and biomarkers for reflux in the upper airway. Furthermore, they offer potential pharmaceutical and surgical intervention targets and are the focus of novel clinical diagnostic tools currently under investigation.

关键词： Microplastic alternatives   Paraffin microparticles   Hediste diversicolor   Biomarkers   Toxicity  

摘要： Plastics are a widespread environmental problem, particularly in the form of small particles or fragments (microplastics). With the purpose of gradually replacing the use of plastics in cosmetic products (primary microplastics), the use of paraffin in microspheres has recently been applied. Paraffin waxes are composed by organic molecules usually derived from petroleum, thus assumed to be chemically and biologically inert, having a lower (eco)toxicity and residence time compared with plastic particles. However, the low ecotoxicity of paraffin waxes may be somewhat questionable, because some paraffin constituents can be absorbed and catabolized, thus exerting biological effects. The main objective of this study was to understand the potential toxic effects of paraffin microparticles on key physiological processes of the polychaeteHediste diversicolor. To attain this objective, this work assessed the acute and chronic effects of three densities (5, 20, and 80 mg L-1) of four size ranges of paraffin particles (from 100 to 1200 mu m) on this epibenthic organism. Although paraffin wax can be generically considered innocuous, the present study was able to demonstrate a significant inhibition in the activity of acetylcholinesterase in acutely exposed organisms and an increase in the activity of glutathione peroxidase, catalase, and glutathione S-transferase under some specific scenarios.

关键词： Tardive dyskinesia   Oxidative stress   Antioxidant   Monoaminoxidase   Tyrosine hydroxylase   Glutamic acid decarboxylase  

摘要： This study evaluated the effect of (+)-catechin, a polyphenolic compound, on orofacial dyskinesia (OD) induced by reserpine in mice. The potential modulation of monoaminoxidase (MAO) activity, tyrosine hydroxylase (TH) and glutamic acid decarboxylase (GAD(67)) immunoreactivity by catechin were used as biochemical endpoints. The interaction of catechin with MAO-A and MAO-B was determined in vitro and in silico. The effects of catechin on OD induced by reserpine (1 mg/kg for 4 days, subcutaneously) in male Swiss mice were examined. After, catechin (10, 50 or 100 mg/kg, intraperitoneally) or its vehicle were given for another 20 days. On the 6th, 8th, 15th and 26th day, vacuous chewing movements (VCMs) and locomotor activity were quantified. Biochemical markers (MAO activity, TH and GAD(67)immunoreactivity) were evaluated in brain structures. In vitro, catechin inhibited both MAO isoforms at concentrations of 0.34 and 1.03 mM being completely reversible for MAO-A and partially reversible for MAO-B. Molecular docking indicated that the catechin bound in the active site of MAO-A, while in the MAO-B it interacted with the surface of the enzyme in an allosteric site. In vivo, reserpine increased the VCMs and decreased the locomotor activity. Catechin (10 mg/kg), decreased the number of VCMs in the 8th day in mice pre-treated with reserpine without altering other behavioral response. Ex vivo, the MAO activity and TH and GAD(67)immunoreactivity were not altered by the treatments. Catechin demonstrated a modest and transitory protective effect in a model of OD in mice.

关键词： Echinacea purpurea   Agrobacterium rhizogenes   rolCgene   Southern blot   Caffeic acid derivatives  

摘要： Echinacea(Echinacea purpureaL.), also known as purple coneflower, is one of the important medicinal plants commonly used for respiratory infections. The aim of this study was to compare different transgenic hairy root lines for growth and secondary metabolite biosynthesis and to select a superior hairy root line for the production of caffeic acid derivatives (CADs).Agrobacterium rhizogenes-mediated root lines showing hairy root phenotypic characteristics were analyzed by the Southern blot analysis and the copy number of therolC gene determined. Significant differences were found among seven hairy root lines evaluated for the copy number ofrolCgene, root growth, total phenolic, and CAD contents. It was concluded that these differences may be due to the position and copy number ofrolCgene in the genome. Across the parameters compared, it was found that line 7 was superior to the other transgenic lines. The results show that the selection of superior transgenic lines is an important factor for the efficient production of secondary metabolites in hairy root cultures ofEchinacea.

关键词： Brick kilns   Heavy metals   BMI   Antioxidants   Lipid profile   Cortisol   Public health  

摘要： The present study was planned to understand the heavy metal burden and its possible actions in blood of occupational females working at brick kilns at Rawat, Pakistan. A total of 232 women were included in the study, of which 114 presented control subjects. Apart from collection of demographic data, fertility indicators and body mass index (BMI), blood was collected from subjects that was later used for the determination of heavy metal concentrations using atomic absorption spectroscopy and haematological profile. Blood was centrifuged and plasma was obtained and stored at - 20 degrees to study biochemical variables (sodium dismutase, peroxidase, reactive oxygen species, thiobarbituric acid reactive species, protein estimation), lipid profile and cortisol concentrations among the two groups. Analysis of heavy metal in blood showed elevated levels of cadmium (3.09 +/- 0.01 mu g/dl), chromium (4.20 +/- 0.02 mu g/dl) and nickel (5.59 +/- 0.03 mu g/dl) in worker's group as compared with control. Increased platelet count;decreased antioxidant enzyme and increased oxidants level;increased total cholesterol, low-density lipoprotein (LDL) and triglyceride (TG);decreased total protein and high-density lipoprotein (HDL);and increased cortisol levels were evident among workers as compared with the control group. The study concluded that occupational workers experience increased heavy metals burden in blood and, therefore, pose a risk to human health by causing reduction in antioxidant enzymes concentration and increase in stress conditions.

关键词： Oxidative stress   Acetylcholinesterase   Crustaceans   Ectothermic   Oxidative damage   Thermal stress  

摘要： Understanding how temperature alone affects biomarkers commonly used in ecotoxicology studies and biomonitoring programs is important to obtain a more real response in field studies, especially in freshwater. Thus, we analyzed the behavioral responses, the lethality, and the biochemical biomarkers in the freshwater crustaceanAegla longirostriat different water temperatures. Animals were exposed under laboratory conditions, to 18 degrees C, 21 degrees C, 24 degrees C, and 26 degrees C for 48 h. There were significant changes in biochemical parameters in different tissues (hepatopancreas, gills, and muscle) and in the behavioral tests inA. *** was especially affected by the elevation of temperature, as showed by the high levels of carbonyl proteins. The activity of acetylcholinesterase increased in a temperature-dependent manner in muscle. Glutathione S-transferase activity decreased with the elevation of temperature in all tissues sampled. The results obtained in this study indicate that when assessing the health of polluted limnic ecosystems through the use of organisms in situ, the intrinsic effect of abiotic factors, such as temperature, on biomarkers must be considered.

关键词： Fragility hip fracture   Bone histomorphometry   Hypovitaminosis D   Osteomalacia   Osteoporosis  

摘要： Background High prevalence of hypovitaminosis D is being reported in Indian patients with fragility hip fracture. The gold standard to diagnose osteoporosis and osteomalacia is bone histomorphometry. There is no study evaluating histopathological histomorphometry in Indian fragility hip fracture patients. The purpose of the study was to evaluate fragility hip fracture patients for histopathological osteomalacia and osteoporosis by histomorphometry and to correlate histopathological findings with biochemical hypovitaminosis D. Materials and Methods A total of 55 patients of fragility hip fractures recruited for prospective cross-sectional study. During definitive fracture fixation of these fragility hip fractures, bone biopsy taken from neck region of femur by a novel approach for histomorphometry. Histomorphometric analysis was based on three indices, namely osteoid seam width, osteoblast surface, and osteoid surface. We also analysed blood bone biochemistry and correlated with bone histomorphometry. Results In fragility hip fracture patients, the prevalence of histomorphometric osteoporosis and osteomalacia were very low (only 9.4% had osteoporosis and none had osteomalacia) however in blood bone biochemistry, we found high prevalence (85.5%) of hypovitaminosis D. We also noted significant changes when correlated bone histomorphometry with different blood bone biochemistry. Conclusion Indian patients with fragility hip fracture were found to have high prevalence of biochemical hypovitaminosis D but unlike western literature, there was low prevalence of histomorphometric osteoporosis with no evidence of histomorphometric osteomalacia. Correct knowledge about metabolic status of fragility hip fracture is required to improve outcome, decrease complications and to optimise cost of the treatment.

关键词： Biomarkers   Joint replacement   Progression  

摘要： Objectives: Clinical trials of new disease-modifying treatments for osteoarthritis should demonstrate a positive effect on a functional outcome or reduction in joint failure in order to be considered successful. Total joint replacement (TJR) surgery may be considered as joint failure, but great variation in the incidence of TJR complicates its use as a study endpoint. Factors predicting elevated risk of TJR could potentially be used to enrich such outcome-trials. Methods: Using cumulative data from two phase three clinical trials with urine samples from 1255 knee OA patients followed for two years, we assessed the value of a series of baseline clinical variables including the uCTX-II biomarker, as predictors of joint-space narrowing, Kellgren-Lawrence-grade progression, and total joint replacement. Results: A prediction-model incorporating age, sex, BMI, CTX-II and KL-grade predicted TJR within the two-year period with an AUC of 0.75 (95% CI: 0.72-0.77). The participants with a cumulative KL-grade between knees of 5, 6, or 7 had a more than 3 times higher risk of TJR in the study period compared to lower (HR: 3.03, 95% CI: 1.54 to 5.96, p = 0.001). Age was associated with increased TJR risk (per 5 years of age: HR: 1.28, 95% CI: 1.03-3.79, p = 0.05). Baseline u-CTX-II was associated with elevated risk of radiographic progression in terms of both JSN and KL-grade. Conclusions: A composite model combining baseline age, sex, BMI, u-CTX-II and KL-grade was able to acceptably predict TJR during a two-year period. In the absence of baseline radiographic OA severity, u-CTX-II independently contributed to prediction of TJR. Baseline urine CTX-II was associated with risk of radiographic progression. (C) 2020 Elsevier Inc. All rights reserved.