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关键词： Non-steroidal anti-inflammatory drugs   Lemna minor   Daphnia magna   Photosynthetic pigments   Biochemical markers   Reproduction  

摘要： Among the most used non-steroidal anti-inflammatory drugs (NSAIDs), ketoprofen (KTF) assumes an important position. Nevertheless, its ecotoxicological effects in non-target organisms are poorly characterized, despite its use and frequency of occurrence in aquatic matrices. Thus, the aim of this study was to evaluate the possible toxicological effects of KTF contamination, in two freshwater species, Lemna minor and Daphnia magna, by measuring biochemical, physiological and population parameters. To attain this objective, both species were exposed to KTF at the same concentrations (0, 0.24, 1.2, 6 and 30 mu g/L). L. minor plants were exposed during 4 d to these levels of KTF, and the enzymatic activity (catalase (CAT), glutathione S-transferases (GSTs) and carbonic anhydrase (CA)), and pigments content (chlorophylls a, b and total and carotenoids) were analyzed to evaluate the toxicity of this drug. D. magna was acutely and chronically exposed to KTF, and enzymatic activities (CAT, GSTs and cyclooxygenase (COX)), the feeding rates, and reproduction traits were assessed. In L. minor, KTF provoked alterations in all enzyme activities, however, it was not capable of causing any alteration in any pigment levels. On the other hand, KTF also provoked alterations in all enzymatic activities in D. magna, but did not affect feeding rates and life-history parameters. In conclusion, exposure to KTF, provoked biochemical alterations in both species. However, these alterations were not reflected into deleterious effects on physiological and populational traits of L. minor and D. magna. (C) 2020 Elsevier Ltd. All rights reserved.

关键词： diabetes   ketogenic   ketosis   low-carbohydrate  

摘要： Purpose of review To summarize the underlying biochemical basis for low-carbohydrate and ketogenic diets (LC/KD) and provide mechanisms to account for demonstrated effectiveness. Recent findings LC/KD continue to have success, to outperform other diets as well as most drugs for weight loss and diabetes treatment. In many cases, LC/KD can effect remission (absence of drugs) or reversal (only metformin or nondiabetes drugs) of type 2 diabetes and can provide a significant adjunct to pharmacology in type 1. Medication is reduced or eliminated in most cases. The results are consistent with the biochemical rationale which stresses the global effects of the glucose-insulin axis. Evidence for the superior effectiveness of LC/KD for metabolic disease is now overwhelming. At the same time, the approach has received only limited support, and in many cases, persistence of the traditional opposition. Clinical practice or research must confront this crisis in order to bring practice in line with current science and to avoid continued harm to medicine and ultimately, the patient.

关键词： Hydroxyapatite  

摘要： Composites of hydroxyapatite (HA) and Bioglass(R)(BG) have been prepared to evaluate their physical, chemical, and biochemical characteristics. Several researchers have attempted to prepare these types of composites to combine the appealing characteristics of BG (such as high bioactivity and osteoinduction) with those of HA. The sintering temperature for the HA-BG composite system used in previous studies was >= 1200 degrees C, which yielded excessive chemical reaction between the precursors (resulting in undesirable biological characteristics), even with addition of as little as 2.5 wt.% BG. In this study, the sintering was performed at 1130 degrees C, slightly below the melting point of BG of 1200 degrees C. This lower sintering temperature prevents excessive reactions between the precursors even with BG content as high as 10 wt.%. The absence of undesirable phases (containing BG < 10 wt.%) resulted in enhanced bioactivity and moderate resorption rate.

关键词： Raman spectroscopy   Amyotrophic lateral sclerosis   Small extracellular vesicles (sEVs)   Large extracellular vesicles (lEVs)   Plasma  

摘要： Sporadic amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease for which there is no validated blood based biomarker. Extracellular vesicles (EVs) have the potential to solve this unmet clinical need. However, due to their heterogeneity and complex chemical composition, EVs are difficult to study. Raman spectroscopy (RS) is an optical method that seems particularly well suited to address this task. In fact, RS provides an overview of the biochemical composition of EVs quickly and virtually without any sample preparation. In this work, we studied by RS small extracellular vesicles (sEVs), large extracellular vesicles (lEVs) and blood plasma of sporadic ALS patients and of a matched cohort of healthy controls. The obtained results highlighted lEVs as a particularly promising biomarker for ALS. In fact, their Raman spectra show that sporadic ALS patients have a different lipid content and less intense bands relative to the aromatic amino acid phenylalanine. (C) 2020 Elsevier Inc. All rights reserved.

关键词： Grape seed extract   Phenolics   Antioxidants   Anthocyanin   Water deficit   Rootstock  

摘要： Pharmaceutical, food and cosmetic industries have shown great interest in grape seed extract due to its premium antioxidant activity with protective effects on human health. However, global climate change has already negatively affected the biochemistry and functionality of such nutraceutical crops. The present study was conducted to reveal the effects of sustained deficit irrigation on certain features of seed extracts obtained from the grape cultivar 'Prima' grafted on six genetically different rootstocks during two consecutive years. In both years, seed weight of 'Prima' grapes grafted on 5 BB significantly decreased in response to water treatments, although the other rootstocks did not impair the seed weight, except for 44-53 & x202f;M in 217. Significant decreases in antioxidant activity of the scion cultivar occurred in response to DI when grafted on 5 BB in both years and in 44-53 & x202f;M in 2017. However, the use of 99 & x202f;R, 110 & x202f;R and 140 Ru did not markedly impair the seed antioxidant activity in response to DI condition in both years. In both years, seed anthocyanins of FI vines were always higher than those of DI vines. In 2017, there were significant decreases in anthocyanins due to DI in vines grafted on 5 BB, 44-53 & x202f;M, 99 & x202f;R and 110 & x202f;R. These rootstocks also led significant decreases in anthocyanins of the second year, while the use of 140 Ru and 1613 & x202f;C rootstocks did not lead significant changes in anthocyanins in both two years. In 2017, total phenolics increased in response to DI, except for the vines grafted on 44-53 & x202f;M. Rootstock-dependent changes in total phenolics in response to irrigation treatments were insignificant for the vines grafted on 5 BB and 44-53 & x202f;M in both two experimental years. Averaged data showed that antioxidant activity showed significantly positive correlation with anthocyanins and total phenols. The findings are anticipated to guide future projects on enhancement of t

关键词： Apiaceae   Umbelliferae   Biogenesis   Essentialoil   Metabolism   Chemophenetics  

摘要： The Essential Oils (EOs) present numerous chemophenetic applications, mostly at infrageneric rank. EOs utilization for this purpose has been questioned because of the external stimulations that control their chemodiversity and quantitative composition. Therefore, they are considered as a class of natural products with questionable systematic significance. Present study exploiting the recent advances on plant volatile biogenesis aims to reestablish and expand the EOs chemophenetic significance. The presented methodology translates EO composition in a biochemical profile, through the chemical structure classification of EOs compounds that links their presence with the activation of endogenous biochemical procedures. The Apiaceae supra-generic classification was utilized to test the proposed methodology. In specific, 44 Greek indigenous Apiaceae taxa, representing all 10 tribes of Apioideae subfamily were collected, distilled and analyzed. The herein applied approach was focused in tribal rank and revealed 10 biochemical entities established on the diversification of their fundamental metabolic routes and biosynthetic pathways activation. The generated biochemical profiles were proven compatible with phenotypic and phylogenetic approaches, but also separated all tribes of Apioideae. Therefore, the proposed methodology can be considered as a promising new systematic tool, which is able to exploit the vast availability of EOs composition data.

关键词： Raphidocelis subcapitata   Metallic nanoparticles   Photosynthetic activity   Energy reserves   Lipid classes  

摘要： Copper oxide nanoparticles (CuO NP) have been produced on a large scale due to their economically interesting thermophysical properties. This heightens the concern about risks they may pose on their release into the environment, possibly affecting non-target organisms. Microalga are important organisms in ecotoxicological studies as they are at the base of the aquatic food chain, but information about their biochemical and photosynthetic changes in response CuO NP are still scarce. We studied the effects of CuO NP in Raphidocelis subcapitata using morphological, photosynthetic and biochemical biomarkers. Our results showed that the NP affected microalgal population growth with 0.70 mg Cu L-1 IC50-96 h (inhibition concentration). Based on predicted environmental concentrations of Cu NPs in aquatic environments, our results indicate potential risks of the NP to microalgae. Algal cell size, granularity and photosynthetic efficiencies were affected by the CuO NP at 0.97 and 11.74 mg Cu L-1. Furthermore, lipid metabolism was affected mostly at the highest NP concentration, but at environmentally relevant values (0.012 and 0.065 mg Cu L-1) the production of sterols (structural lipids) and triacylglycerols (reserve lipid) increased. Moreover, we found evidence of cell membrane impairment at the highest CuO NP concentration, and, as a photosynthetic response, the oxygen evolving complex was its main site of action. To the best of our knowledge, this is the first study to date to investigate microalgal lipid composition during CuO NP exposure, showing that it is a sensitive diagnostic tool. This research demonstrated that CuO NP may affect the physiology of R. subcapitata, and because they were observed in a primary producer, we foresee consequences to higher trophic levels in aquatic communities. (C) 2020 Elsevier Ltd. All rights reserved.

关键词： DNA methylation   Epigenetic   Selenium nanoparticle   Transcription factors   Toxicity  

摘要： This study aimed to explore whether supplementation of the culture medium with selenium nanoparticles (nSe) can influence growth, biochemistry, expression of transcription factors, and epigenetic DNA methylation in Capsicum annuum. The seeds were grown in hormone-free MS culture medium supplemented with nSe (0, 0.5,1, 10, and 30 mgL(-1)) or corresponding doses of bulk type selenate (BSe). Incorporation of nSe into the medium caused variations in morphology and growth in a manner dependent on the dose and Se type. The low doses of nSe displayed growth-promoting effects, whereas nSe at 10 and 30 mgL(-1) were associated with severe toxicity and abnormality in leaf and root development. MSAP analysis confirmed the substantial variation in cytosine DNA methylation in response to the toxic dose of nSe exhibiting epigenetic modification. The nSe toxicity was associated with DNA hypermethylations. The nSe treatments transcriptionally upregulated the bZIP1 transcription factor by an average of 3.5 folds. With a similar trend, the upregulation (mean = 9.8 folds) in the expression of the WRKY1 transcription factor resulted from the nSe application. The nSe0.5 or nSe1 treatments resulted in a significant induction (mean = 48%) in nitrate reductase activity. A high dose of nSe led to an increase in proline concentration. The nSe treatments were also associated with modifications in activities of peroxidase and catalase enzymes. Besides, the nSe utilization increased the activity of phenylalanine ammonia-lyase enzyme (mean = 76%) and concentrations of soluble phenols (mean = 51%). The toxic dose of nSe also caused abnormalities in the structure of the stem apical meristem. The nSe toxicity was also associated with inhibition in the differentiation of xylem tissues. These findings provide novel insights into the nSe-associated molecular variations in conferring the modified growth, anatomy, and metabolism. (C) 2020 Elsevier Ltd. All rights reserved.

关键词： Vanadium   African giant rats   Hepatorenal toxicity   Biochemical assay   Ultrastructure  

摘要： We studied the hepatic and renal impact of sodium metavanadate (SMV) exposure in African giant rats (AGR). Twelve male AGR were used and divided into two groups. The control group received sterile water while the SMV-exposed group received 3 mg/kg SMV intraperitoneally for 14 days. SMV exposed AGR groups showed significantly decreased activities of serum AST, ALT, ALP and creatinine concentration but increased blood urea nitrogen (BUN), albumin and globulin concentrations. Kidney ultrastructure examination revealed atrophy of the glomerular tuft, loss of podocytes, distortions of the endothelium and glomerular basement membrane. The liver sinusoids fenestration phenotypes were abnormal. Hepatocytes exhibited hypertrophy with uneven, crenated and dentate nuclei. SMV exposure induced activation of monocytes, as well as Kupffer and fibrous cells. Alterations in glomerular podocytes and cell-cell and cell matrix contact and inflammatory liver fibrosis are key events in progressive glomerular failure and hepatic damage due to SMV intoxication.

关键词： appendicitis   C-reactive protein   inflammatory marker   white cell count  

摘要： Background Acute appendicitis is a common general surgical condition where diagnosis is predominantly clinical, with the aid of adjunct investigations. This study reviews the relationship between normal and elevated biochemical inflammatory markers, duration of symptoms and proven appendicitis. Methods A multicentre prospective observational study was performed across 27 centres and included a total of 949 patients with clinical suspicion of appendicitis, who had both white cell count (WCC) and C-reactive protein (CRP) recorded and underwent appendicectomy. Results A total of 90.4% of patients with raised WCC and CRP had appendicitis with a positive predictive value (PPV) of 0.9 and negative predictive value (NPV) of 0.4. Sensitivity and specificity of elevated WCC (sensitivity 66.5%, specificity 66.0%) and elevated CRP (sensitivity 77.3%, specificity 52.0%) lie within ranges identified by previous studies. A total of 39.8% of patients with normal CRP and WCC had appendicitis. Sensitivity and PPV for patients with elevated inflammatory markers were high until 48 h of symptoms (sensitivity 94%, PPV 0.87). NPV was elevated after 24 h (NPV 0.65 in patients with 24-48 h of symptoms, and 0.61 after 48 h), whilst those with symptoms less than 24 h had a lower NPV of 0.52. Conclusion Whilst elevated inflammatory markers are a helpful aid in the diagnosis of appendicitis, they should not be relied on by themselves. Nor can normal inflammatory markers be used to exclude appendicitis, even in those with prolonged duration of symptoms. The diagnosis of appendicitis should be guided by a combination of clinical judgement with the assistance of inflammatory markers.