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关键词： Transcriptome   Albinism   Chlorophyll   Carotenoid   Transcription factor   Areca catechu L.  

摘要： Frequent striped leaf albinism occurring in young seedlings leads to production loss of arecanut (Areca catechu L.) industry. Previous efforts has proved that this albinism phenotype was determined by genetic factors. However, the mechanism underlying albinism in arecanut remains unclear. In this study, to elucidate the regulatory mechanism of striped leaf albinism, comparison analysis was performed between leaves of normal and albinotic seedlings at physiological, biochemical and transcriptomic levels in arecanut. The albinotic leaves showed obvious degeneration in chloroplast, low chlorophyll content and reduced photosynthetic capacity. More than 5000 DEGs (differentially-expressed genes) was identified between normal and albinotic leaves. Among them, genes involved into the biosynthesis of chlorophyll, carotenoid and anthocyanin were significantly down-regulated in albinotic leaves. On the contrary, genes involved in leaf senescence and ABA (abscisic acid) synthesis were up-regulated in albinotic leaves. Unexpectedly, most genes involved in chloroplast development were up-regulated in albinotic leaves, indicating different regulatory mechanism of albinism in arecanut. Furthermore, transcription factor family genes, such as AP2/ERF-ERF (APETALA2/ethylene responsive factor), NAC (NAM/ATAF/CUC) and WRKY, were identified as DEGs between normal and albinotic leaves, which also indicated the senescence of albinotic leaves. The results indicated that the albinism mechanism of arecanut is different with those reported in other plants. Thus our data provides new insights into the mechanism underlying albinism. The genes related to albinism of arecanut identified in this study would be important targets for genetic modification or molecular markers development, which will be critical for improving the cultivation efficiency of this cash crop.

关键词： Paper microfluidics   Programmable valve matrix   Binary control logic   Multiplex colorimetric assays  

摘要： The integration of simple fabricated paper devices with a multiplexing fluid control technology are the keys for extending traditional microfluidic applications to paper-based devices. However, paper devices to date have lacked a method for addressing the integration of complex fluid manipulations. By featuring a scalable and programmable mechanical valve matrix that is actuated by push-pull solenoids, we present a paper microfluidic multiplexing technology for performing biochemical assays in a high degree of autonomy. The technology allows every channel of a paper network to be autonomously addressed and isolated while uses a minimal number of control elements, efficiently reducing its complexity. The technology is implemented in an integrated portable system including a multiplexor controller, a relay matrix, a paper device, on-chip temperature control unit and an image analyzer. Biochemical reaction signals can be acquired and automatically interpreted via a self-built mobile App. A prototype that consists of 8 independent valve lines was demonstrated, allowing multiplexed control of a paper device with 16 operating channels. After thoroughly studying the behaviour of fluid transport in the paper device using both numerical simulation and experimentations, multiplex colorimetric assays of heavy metal samples and glucose in common soft drinks and artificial saliva samples were analyzed. To the best of our knowledge, this is the first demonstration of a simple fabricated paper device integrated with a valve multiplexing technology. The scalability of this integration makes the technology ideally suited for high throughput analysis and holds great potential for progressing large scale integration of paper microfluidics.

关键词： Vermicomposting   Continuous feeding   Pleurotus ostreatus   Spent mushroom substrate   PLFA analysis   Enzymatic activity  

摘要： Pleurotus ostreatus is one of the most cultivated mushrooms in the Czech Republic. The production of 1 kg of mushrooms generates about 5 kg of spent mushroom substrate. A gentle and fast method for using this substrate is vermicomposting. Vermicomposting of spent mushroom substrate using Eisenia andrei was conducted for seven months. For control purposes, a treatment without earthworms was also prepared. The vermicomposting process used vertical continuous feeding vermicomposters. The agrochemical and biological parameters were analysed. Values of electrical conductivity were very high in both vermicomposters (higher than 2000 mu S/cm). During the vermicomposting process the C/Nratio decreased. The number and biomass of earthworms decreased with the age of the layers. The values of total P, K and Mg were higher in the vermicomposter without earthworms. There were also lower microbial phospholipid fatty acids content - than in the vermicomposter with earthworms. However, the fungal phospholipid fatty acids contentwere two times higher in the vermicomposter without earthworms. The highest hydrolytic enzyme activity was found in lipase, acid phosphatase and beta-D-glucosidase. Most hydrolytic enzymes were more active in the vermicomposter without earthworms, with the exception of arylsulphatase. Mn-peroxidase activity was higher in the vermicomposter without earthworms and laccase activity was below the detection limit. (C) 2020 Elsevier B.V. All rights reserved.

关键词： Cholic aad   Molecular dynamics simulation   Kinase inhibitor   Drug discovery   MARK4 and cancer cell lines  

摘要： Microtubule affinity regulating kinase (MARK4) is considered as a potential drug target for diabetes, cancer, and neurodegenerative diseases. Since the role of MARK4 in the phosphorylation of tau protein and subsequently Alzheimer's disease has been established, therefore, we have investigated the binding affinity and MARK4 inhibitory potential of cholic acid (CHA) using both computational and spectroscopic methods. Molecular docking suggested a strong binding of CHA to the functionally important residues of MARK4. We further performed 500 ns molecular dynamics simulation which suggested the MARK4-CHA system was quite stable throughout the simulation trajectory. CHA potential binds to the MARK4 with a binding constant (K) of 10(7) M-1 at 288 K. Further, MARK4 activity was inhibited by CHA with an IC50 = 5.5 mu M. Further insights into the thermodynamic parameters suggested that MARK4-CHA complex formation is driven by both electrostatic and van der Waals interactions. Overall study provides a rationale to use CHA in the drug development via MARK4 inhibition, towards possible therapeutic implications in neurodegenerative diseases. (C) 2020 Elsevier B.V. All tights reserved.

关键词： chiral biosensing   chiral plasmonics   chirality transfer   circular dichroism   optical activities  

摘要： Determining the structural chirality of biomolecules is of vital importance in bioscience and biomedicine. Conventional methods for characterizing molecular chirality, e.g., circular dichroism (CD) spectroscopy, require high-concentration specimens due to the weak electronic CD signals of biomolecules such as amino acids. Artificially designed chiral plasmonic metastructures exhibit strong intrinsic chirality. However, the significant size mismatch between metastructures and biomolecules makes the former unsuitable for chirality-recognition-based molecular discrimination. Fortunately, constructing metallic architectures through molecular self-assembly allows chirality transfer from sub-nanometer biomolecules to sub-micrometer, intrinsically achiral plasmonic metastructures by means of either near-field interaction or chirality inheritance, resulting in hybrid systems with CD signals orders of magnitude larger than that of pristine biomolecules. This exotic property provides a new means to determine molecular chirality at extremely low concentrations (ideally at the single-molecule level). Herein, three strategies of chirality transfer from sub-nanometer biomolecules to sub-micrometer metallic metastructures are analyzed. The physiochemical mechanisms responsible for chirality transfer are elaborated and new fascinating opportunities for employing plasmonic metastructures in chirality-based biosensing and bioimaging are outlined.

关键词： Decapods   Ecotoxicology   Oxidative stress   Pesticides   Toxicity  

摘要： Freshwater ecosystems are constantly threatened by the advance of agricultural activities. Abiotic variables (such as temperature, ammonia, and nitrite) and contaminants (e.g. pesticides) can potentially interact, increasing metabolism and the absorption of toxic substances, which can alter the ability of organisms to establish adequate stress responses. This study aimed to verify which pesticides were most frequently found and in the greatest quantities in low-order streams, and whether the combination of these pesticides with the abiotic variables altered the biological metabolism of aeglids. These freshwater crustaceans are important shredders that inhabit low-order streams and are sensitive to disturbances and/or abrupt environmental variations. The animals were exposed in situ in four streams (reference site and sites 1, 2, and 3). The reference site is a preserved stream with no apparent anthropogenic interference where aeglids still occur, while the other sites no longer exhibit populations of these animals and are influenced by agricultural activities. The exposure was performed bimonthly from November 2017 to September 2018 and lasted 96 h. Measured abiotic data and water samples were collected through all days of exposure. The analyzed biochemical parameters were acetylcholinesterase activity in muscle;and glutathione S-transferase, lipid peroxidation, protein carbonylation, non-protein thiols, antioxidant capacity against peroxides, and reactive oxygen species (ROS) in muscle, gills, and hepatopancreas. We found 24 active principles of pesticides, the most frequently being clomazone, atrazine, and propoxur. Bentazone was present at the highest amounts. The parameters evaluated in this study, including biochemical biomarkers and abiotic factors measured from the water, provided a separation of the months as a function of environmental conditions. There was a difference in activity and biomarker levels throughout the year within the same site and in some mo

关键词： Beta vulgaris L   Brassica oleracea var   capitata   Heavy metal   Phytotoxicity   Vegetables   Food safety  

摘要： Excess copper (Cu) in plant tissue may cause toxicity and pose a risk to human health. However, this is still not well known in the literature. The aim of this study was to evaluate the effect of Cu concentrations in nutrient solution on growth, physiological and biochemical parameters in beets and cabbages, in addition to human health risk assessment. Beets and cabbages were grown for 90 days in pots with sand and fertigated with nutrient solution containing five Cu concentrations (0.02, 0.27, 0.52, 0.77 and 1.02 mg L-1) Growth, physiological and biochemical parameters were evaluated in leaves, in addition to Cu contents and accumulation in organs of both species. We estimated the average portion intake of Cu (API(cu)) and the hazard quotient (HQ) associated with the consumption of beet tuberous root and cabbage head. Increasing Cu in solution reduced beet growth and increased Cu content and accumulation in organs of beet and cabbage, resulting in an increase in API(cu) and HQ. This highlights potential risks to human health, which are proportional to intake of in natura beet tuberous root and cabbage head.

关键词： Lemna minor   Pharmaceuticals   Pigments content   Biochemical alterations   Plant toxicology  

摘要： Salicylic add (SA) is a pharmaceutical drug that may exert toxic effects by its own: however, simultaneous exposure of plants to SA and to other substances, often results in the significant changes in the patterns of toxic response/resistance to these other sources of chemical stress. Thus, the aim of this work was to investigate the capacity of SA of modulating Lemna minor responses co-exposed to the pharmaceutical drug, diclofenac - DCF. To attain this objective, L minor was exposed for 7 days, to DCF alone, and to combinations of DCF with SA. After exposure, biochemical, physiological and population endpoints were analyzed as follows: catalase (CAT) and glutathione S-transferases (GSTs) activities, pigments content (chlorophyll a (Chl a), b (Chl b) and total (TChl), carotenoids (Car) and [Chl a]/[Chl b] and [TChl]/[Car] ratios), and growth specific rate, fresh weight and root length. Single exposures to DCF were capable of causing effects in all analyzed endpoints. However, coexposure of DCF with SA partially reverted these effects. Finally, we may suggest that SA is capable to prevent the toxicity of DCF in macrophytes, by modulating the toxic response of exposed plants. (C) 2020 Elsevier B.V. All rights reserved.

关键词： Obese   Overweight   Inflammation   Biochemical biomarkers   Ramadan   Fasting  

摘要： Background: To determine the effects of Ramadan intermittent fasting (RIF) on inflammatory (C-reactive protein (CRP), interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha)) and biochemical markers of liver-renal function (aspartate aminotransferase (AST), alanine amino transferase (ALT), bilirubin, lactate dehydrogenase (LDH), urea and creatinine) in males with obesity. Materials and methods: Twenty-eight males with obesity were randomly allocated to an experimental group (EG, n = 14) or a control group (CG, n = 14). The EG group completed their fasting rituals for the entire month of Ramadan (30 days) whereas the CG group continued with their normal daily habits. Blood samples were collected 24 h before the start of Ramadan (T0), on the 15th day of Ramadan (T1), the day after the end of Ramadan (T2), and 21 days after the end of Ramadan (T3). Resting plasma volume variation between pre and post-RIF (Delta PV) was calculated. Results: Decreases were noted for interleukin-6 (p = 0.02, d = 1.4) and tumor necrosis factor-alpha (p = 0.01, d = 0.7), with no changes for C-reactive protein (p = 0.3;d = 0.1) in the EG compared to CG group. There were no changes (P > 0.05) in APV recorded after RIF for either EG (-0.035 +/- 0.02%) and CG (0.055 +/- 0.06%). Conclusion: This study demonstrates that RIF improves systemic inflammation biomarkers in males with obesity. Moreover, RIF did not negatively affect biomarkers of liver and renal function.