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关键词： Mechanotransduction   Shear stress   Lymphatic vascular development   Valve   Lymphatic endothelial cells   PROX1   FOXC2   GATA2   Wnt   YAP   TAZ   FLUID SHEAR-STRESS   GROWTH-FACTOR-C   LYMPHEDEMA-DISTICHIASIS SYNDROME   NITRIC-OXIDE PRODUCTION   FACTOR-B-CHAIN   ENDOTHELIAL-CELL   COUP-TFII   VALVE DEVELOPMENT   EMBRYONIC LYMPHANGIOGENESIS   LYMPHOVENOUS HEMOSTASIS  

摘要： Lymphatic vasculature is an integral part of the cardiovascular system where it maintains interstitial fluid balance. Additionally, lymphatic vasculature regulates lipid assimilation and inflammatory response. Lymphatic vasculature is composed of lymphatic capillaries, collecting lymphatic vessels and valves that function in synergy to absorb and transport fluid against gravitational and pressure gradients. Defects in lymphatic vessels or valves leads to fluid accumulation in tissues (lymphedema), chylous ascites, chylothorax, metabolic disorders and inflammation. The past three decades of research has identified numerous molecules that are necessary for the stepwise development of lymphatic vasculature. However, approaches to treat lymphatic disorders are still limited to massages and compression bandages. Hence, better understanding of the mechanisms that regulate lymphatic vascular development and function is urgently needed to develop efficient therapies. Recent research has linked mechanical signals such as shear stress and matrix stiffness with biochemical pathways that regulate lymphatic vessel growth, patterning and maturation and valve formation. The goal of this review article is to highlight these innovative developments and speculate on unanswered questions.

关键词： Oleuropein   Stroke   ACE   Protein disulfide isomerase   Oxidative stress   OXIDATIVE STRESS   STROKE   FIBRINOGEN   TISSUE   RISK   ISCHEMIA/REPERFUSION   THROMBOSIS   MODEL   DRUG  

摘要： This study was designed to evaluate the underlying protective mechanisms of oleuropein involved in alleviating brain damage in a rat model of ischemic stroke. Male Wistar rats were divided into four groups; Control, stroke (MCAO), MCAO + clopidogrel (Clop) and MCAO + oleuropein (Ole). Results showed that the MCAO group evidenced significant brain edema (+ 9%) as well as increases of plasma cardiac markers such as lactate deshydrogenase (LDH), creatine kinase (CK-MB), fibrinogen and Trop-T by 11 %, 43%, 168 and 590%, respectively, as compared to the control group. Moreover, infarcted rats exhibited remarkable elevated levels of angiotensin converting enzyme (ACE), both in plasma and brain tissue, with astrocyte swelling and necrotic neurons in the infarct zone, hyponatremia, and increased rate of thiobarbituric acid-reactive substances (TBARS) by 89% associated with decreases in the activity of superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase (Cat) by 51%, 44 and 42%, respectively, compared to normal control rats. However, MCAO rats treated with oleuropein underwent mitigation of cerebral edema, correction of hyponatremia, remarkable decrease of plasma fibrinogen and cardiac dysfunctional enzymes, inhibition of ACE activity and improvement of oxidative stress status in brain tissue. Furthermore, in silico analysis showed considerable inhibitions of ACE, protein disulfide isomerase (PDI) and TGF-beta 1, an indicative of potent anti-embolic properties. Overall, oleuropein offers a neuroprotective effect against ischemic stroke through its antioxidative and antithrombotic activities.

关键词： Drugs   Crustaceans   Biomarkers   Population effects   Sublethal effect   PHARMACEUTICAL DRUG PARACETAMOL   CLAM RUDITAPES-PHILIPPINARUM   MULTI-RESIDUE ANALYSIS   SWIMMING BEHAVIOR   OXIDATIVE STRESS   ZINC PYRITHIONE   BROAD RANGE   WATER   ACETAMINOPHEN   REPRODUCTION  

摘要： Exposure of nontarget organisms to therapeutic agents can cause distinct toxic effects, even at low concentrations. Paracetamol is a painkiller drug, widely used in human and veterinary therapies, being frequently found in the aquatic compartment in considerable amounts. Its toxicity has already been established for some species, but its full ecotoxicological potential is still not sufficiently described. To characterize the ecotoxicity of paracetamol, the present study evaluated several parameters, such as acute immobilization (EC50 calculation), biochemical alterations, and behavioral effects, in two species of freshwater microcrustaceans of the genus Daphnia (D. magna and D. longispina). To increase the relevance of the data obtained, animals were exposed to levels of paracetamol similar to those already reported to occur in the wild. Data showed antioxidant responses in both species, namely an increase of catalase and GSTs activities in D. magna. On the contrary, effects of paracetamol on D. longispina included only an impairment of GSTs activity. Despite the absence of anticholinesterasic effects, behavioral modifications were also observed. This set of data indicates that realistic levels of paracetamol may trigger the activation of the antioxidant defense system of freshwater crustaceans, causing changes in behavioral traits (increase in swimming time, but with a reduction in swimming distance) of unknown etiology that are likely to affect normal life traits of wild populations.

关键词： Acoustic emission   Hydric stress   Physical elicitor   Plants stimulant   Capsaicinoids   Gene transcription   GENE-EXPRESSION   SOUND   TOLERANCE   EXPOSURE   PLANTS   TREES  

摘要： At specific vibration frequencies like ones generated by insects such as caterpillar chewing and bee's buzz-pollination turn on the plants secondary metabolism and their respective pathways gets activated. Thus, studies report that vibrations and sound waves applied to plants improves their fitness performance. Commonly, acoustic treatments for plants have used arbitrarily random frequencies. In this work, a group of signals obtained from hydric-stressed plants was recorded as vibrational patterns using a laser vibrometer. These vibration-signals were classified as representative of each condition and then externally applied as Acoustic Emission Patterns (AEP). The present research hypothesized that specific vibration frequencies could "emulate" a plant signal through mechanical energy based on tplant's ability to recognize vibration pattern similarity to a hydric status. This investigation aimed to apply the AEP's as characteristic vibrations classified as Low hydric stress (LHS), medium hydric stress (MHS), and high hydric stress (HHS) to evaluate their effect on healthy-well watered plants at two developmental stages. In the vegetative stage, the gene expression related to antioxidant and hydric stress responses was assessed. The LHS, MHS, and HHS acoustic treatments up-regulated the peroxidase (Pod) (similar to 2.8, 1.9, and 3.6-fold change, respectively). The superoxide dismutase (Mn-sod) and phenylalanine ammonia-lyase (Pal) genes were upregulated by HHS (similar to 0.23 and similar to 0.55-fold change, respectively) and, the chalcone synthase (Chs) gene was induced by MHS (similar to 0.63-fold-change). At the fructification stage, the MHS treatment induced a significant increase in Capsaicin content (5.88-fold change), probably through the at3and kas gene activation. Findings are correlated for a better understanding of plant responses to different multi frequency-signals tones from vibrations with potential for agricultural applications.

关键词： Antioxidant enzymes   DEHP   Detoxification enzymes   G   pulex   Histopathology   OXIDATIVE STRESS   RAT-LIVER   DIETHYL PHTHALATE   CRUSTACEA   INDUCTION   SALINITY   ENZYMES   DAMAGE   DBP  

摘要： This study aimed to reveal the toxic characteristics of di-(2-ethylhexyl) phthalate (DEHP) by examining the biochemical and histopathological changes in Gammarus pulex, exposed to different doses of DEHP. For this purpose, the lethal concentration 50 (LC50) value of the DEHP was determined by using a static test and found to be 0.079 +/- 0.01 ppm. Three subletal doses of DEHP were applied to the G. pulex for 24 and 96 h. Superoxide dismutase (SOD), catalase (CAT), cytochrome P450 1A1 (CYP1A1), and glutathione S-transferase (GST) activities were measured using commercial ELISA kits. The caspase method, which is an immunohistochemical analysis method, was used to determine the apoptosis that occurred in the G. pulex. The results showed that the CYP1A1 activities decreased in the groups exposed to different doses of DEHP compared to the control group (p > 0.05). CAT activity was found to increase in the application groups at the 24 and 96 h compared to the control group. In addition, it was found that SOD and GST activities increased at the 96 h compared to the control group. In light of the microscope examination of the model organism, hemolymphatic lacunae filled with hemolymph and reduction or absence of hemolymphatic ducts were observed especially in the G. pulex gills. Collapse of the gills and hyperplasia were observed after 96 h. As a result, it is suggested that changes in SOD, CAT, and GST activities can potentially be used as sensitive biomarkers for risk assessment in the environment and increased immunoreactivity in G. pulex caused by DEHP depending on increased application doses and application times.

关键词： Defense system   Oxidative stress   Pesticides   Pistacia vera   Plant biochemistry   OXIDATIVE STRESS   PHYSICOCHEMICAL PROPERTIES   ANTIOXIDATIVE ENZYMES   SUPEROXIDE-DISMUTASE   ORGANIC-COMPOUNDS   ACID   METABOLISM   GLUTATHIONE   PEROXIDASE   MOBILITIES  

摘要： Pesticides may manipulate plant physiology as non-target organisms. In this study, we examined biochemical responses of pistachio plants (Pistacia vera L.) to imidacloprid and phosalone as common pesticides used to control pistachio psyllids. Enzymatic characterization in treated plants with pesticides showed greater specific activities of superoxide dismutase, catalase, ascorbate peroxidase, guaiacol peroxidase, phenylalanine ammonia-lyase, glutathione reductase, and glutathione S-transferase compared with untreated plants during 14 days after treatment. Further experiments displayed elevated levels of total phenols and total proteins coupled with significant increases in proline and total soluble carbohydrate contents in treated plants in comparison to untreated plants. Moreover, pesticide treatment leads to a significant decrease in polyphenol oxidase activity. Nevertheless, no significant changes in contents of hydrogen peroxide, malondialdehyde, total chlorophyll, and electrolyte leakage index were obtained in treated plants. Pesticides' impacts on host plant physiology resulted in similar responses between two pesticides with differences in peak days. Overall, the findings of this study provide an insight into the side effects of phosalone and imidacloprid, chemicals with no specific target site in plants, on the physiology and biochemistry of pistachio plants at recommended rates.

关键词： Timothy grass   Poaceae   Allergy   Asthma   Proteins   Allergens   Lipids   Pollen cytoplasmic granules   EICOSANOID-LIKE SUBSTANCES   ICE NUCLEATING ABILITY   GRASS-POLLEN   IMMUNOLOGICAL CHARACTERIZATION   MAJOR ALLERGEN   MOLECULAR CHARACTERIZATION   CYTOPLASMIC GRANULES   P 4   POSTTRANSLATIONAL MODIFICATIONS   CARBOHYDRATE MOIETIES  

摘要： The Poaceae family is composed of 12,000 plant species. Some of these species produce highly allergenic anemophilous pollen grains (PGs). Phleum pratense pollen grains (PPPGs) emerged as a model for studies related to grass allergy. The biochemical composition of allergenic PGs has not yet been fully described despite potential health effects of PG constituents other than allergenic proteins. This review brings together the information available in literature aiming at creating a comprehensive picture of the current knowledge about the chemical composition of allergenic PGs from timothy grass. PPPGs have an average diameter between 30-35 mu m and the mass of a single PG was reported between 11 and 26 ng. The pollen cytoplasm is filled with two types of pollen cytoplasmic granules (PCGs): the starch granules and the polysaccharide particles (p-particles). Starch granules have a size between 0.6-2.5 mu m with an average diameter of 1.1 mu m (estimated number of 1000 granules per PG) while p-particles have a size ranging around 0.3 to 0.4 mu m (estimated number between 61,000-230,000 p-particles per PG). The rupture of PG induces the release of PCGs and the dispersion of allergens in the inhalable fraction of atmospheric aerosol. PPPGs are composed of sporopollenin, sugars, polysaccharides, starch, glyco-proteins (including allergens), amino-acids, lipids, flavonoids (including isorhamnetin), various elements (the more abundant being Si, Mg and Ca), phenolic compounds, phytoprostanoids, carotenoids (pigments) metals and adsorbed pollutants. PPPG contains about a hundred different proteins with molecular masses ranging from 10 to 94 kDa, with isoelectric points from 3.5-10.6. Among these proteins, allergens are classified in eleven groups from 1 to 13 with allergens from groups 1 and 5 being the major contributors to Phl p pollen allergy. Major allergen Phl p 5 was quantified in PPPGs by several studies with concentration ranging from 2.7 and 3.5 mu ***(-1) in unpollut

关键词： Novel beta-glucosidase   Glucose tolerant   Saccharomonospora sp. NB11   Molecular docking   TRICHODERMA-REESEI   PURIFICATION   HYDROLYSIS   OVEREXPRESSION   INHIBITION   METAGENOME   CELLOBIOSE   ETHANOL  

摘要： Most of the presently known beta-glucosidases are sensitive to end-product inhibition by glucose, restricting their potential use in many industrial applications. Identification of novel glucose tolerant beta-glucosidase can prove a pivotal solution to eliminate end-product inhibition and enhance the overall lignocellulosic saccharification process. In this study, a novel gene encoding beta-glucosidase BglNB11 of 1405bp was identified in the genome of Saccharomonospora sp. NB11 and was successfully cloned and heterologously expressed in E. coli BL21 (DE3).The presence of conserved amino acids; NEPW and TENG indicated that BglNB11 belonged to GH1 beta-glucosidases. The recombinant enzyme was purified using a Ni-NTA column, with the molecular mass of 51 kDa, using SDSPAGE analysis. BglNB11 showed optimum activity at 40 degrees C and pH 7 and did not require any tested co-factors for activation. The kinetic values, K-m, V-max, k(cat), and k(cat)/K-m of purified enzyme were 0.4037 mM, 5735.8 mu mol/min/mg, 5042.16 s(-1) and 12487.71 s(-1) mM(-1), respectively. The enzyme was not inhibited by glucose to a concentration of 4 M but was slightly stimulated in the presence of glucose. Molecular docking of BglNB11 with glucose suggested that the relative binding position of glucose in the active site channel might be responsible for modulating end product tolerance and stimulation. beta-glucosidase from BglNB11 is an excellent enzyme with high catalytic efficiency and enhanced glucose tolerance compared to many known glucose tolerant beta-glucosidases. These unique properties of BglNB11 make it a prime candidate to be utilized in many biotechnological applications.

关键词： apoptosis   biochemical alterations   diabetes mellitus   diabetic retinopathy   inflammation   oxidative stress   treatments   PROTEIN-KINASE-C   OXIDATIVE STRESS   ALDOSE REDUCTASE   COMPLICATIONS   PATHOGENESIS   ACTIVATION   ISOFORMS   THERAPY   GAMMA  

摘要： Diabetes mellitus (DM) is a chronic metabolic disorder characterized by impaired glucose homeostasis, insulin resistance and hyperglycemia. Among its serious multisystemic complications is diabetic retinopathy (DR), which develops slowly and often insidiously. This disorderdthe most common cause of vision loss in working-age adultsdis characterized by functional and morphological changes in the retina. It results from the exacerbation of ischemic and inflammatory conditions prompted by alterations in the blood vessels, such as the development of leukostasis, thickening of the basement membrane, retinal neovascularization and fibrovascular tissue formation at the vitreoretinal interface. The pathogenic alterations are usually triggered at the biochemical level, involving a greater activity in 4 pathways: the polyol pathway, the hexosamine pathway, the formation of advanced glycation end-products and the activation of protein kinase C isoforms. When acting together, these pathways give rise to increased levels of reactive oxygen species and decreased levels of endogenous antioxidant agents, thus generating oxidative stress. All current therapies are aimed at the later stages of DR, and their application implies side effects. One possible strategy for preventing the complications of DM is to counteract the elevated superoxide production stemming from a high level of blood glucose. Accordingly, some treatments are under study for their capacity to reduce vascular leakage and avoid retinal ischemia, retinal neovascularization and macular edema. The present review summarizes the biochemical aspects of DR and the main approaches for treating it. (c) 2020 Canadian Diabetes Association.

关键词： Aazulene   Cultivar   Epicuticular wax   Hentriacontanone-16   Infestation   Onion thrips   Thrips tabaci   EPICUTICULAR LEAF WAXES   THYSANOPTERA THRIPIDAE   FATTY-ACIDS   RESISTANCE   SUSCEPTIBILITY   LINDEMAN   DAMAGE   INSECTICIDES   ELONGATION  

摘要： Onion thrips is a major threat to onion crop throughout the world. It is a potential vector of Iris yellow spot virus and causes significant economic damage to bulb production. Phenotypic and biochemical traits of onion cultivars were assessed against Thrips tabaci. Onion Gawran LR-241 (OG) cultivar was tolerant against the infestation of T. tabaci whereas Onion White (OW) was susceptible. Number and size of stomata, cuticle thickness, cell wall thickness and surface wax of onion leaves were studied with the help of scanning electron microscope and quantitative and qualitative analysis was carried out to estimate epicuticular wax and other bio-chemical components through GC/MS. Onion Gawran has thick cell wall, sharp and dense wax crystals, wider central angle and small sized stomata compared to other cultivars. Epicuticular wax components of OG cultivar were heptacosane (5.2%), octacosanol-1 (9.2%), 2-methyl octacosane (4.2%), heptadecanol-1 (5.2%), hexacosanol-1 (4.2%), azulene, 1,4-dimethyl-7-(1-methylethyl) (36.9%), hexadecanoic acid (1.95%), heptadecane (4.2%), triacontanol-1 (5.8%) and hentriacontanone-16 (23.40%). Azulene, 1, 4-dimethy-l-7-(1-methy-l-ethyl) was only found 36.9% in OG but absent in other three cultivars. 2-methyl octacosane was absent in Poona Red Desi and OW cultivars. Hentriacontanone-16, 2-methyl octacosane, fatty alcohols (Octacosanol-1 and Triacontanol-1) and azulene, 1, 4-dimethy-l-7-(1 methy-l-ethyl) were effective in the formation of epicuticular wax in onion cultivars. It implies that phenotypic and biochemical characteristics of OG cultivar proved as resisting features to T. tabaci.