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关键词： Maize   BLSB   Resistance   Enzymatic activity   Inbreds  

摘要： Maize (Zea mays L.) is a staple food in many parts of the world. In addition to being used as grain, animal feed, production of corn ethanol, starch, syrup etc., it has been widely consumed as a vegetable in the form of baby corn and sweet corn. Banded leaf and sheath blight (BLSB) is one of the major diseases affecting maize and is caused by Rhizoctonia solani f. sp. sasakii Exner. In the experiment forty six maize inbreds were screened for their reaction against the BLSB pathogen following artificial inoculation. Two inbred lines namely, EV1417 and CML-323 produced resistant and moderately resistant disease reaction respectively. Biochemical studies indicated the presence of a high level of pre-infectional barriers in the resistant line. Further, higher level of defense related enzymatic activities of peroxidase and poly phenol oxidase were detected in the resistant inbred line. After 48 h of inoculation, in comparison to highly susceptible EV1428, electrolyte leakage was found to be stabilized in EV1417 and CML-323. This study clearly establishes the presence of effective pre-infection barriers and induced biochemical defence mechanisms operating in the resistant inbred line. The identified resistant line EV1417 is further being used in BLSB disease resistance breeding programmes.

关键词： Immune response   Cytokines   Hematology   Mulberry   Hydrophila spp   MAL   Nile tilapia   Morus alba  

摘要： The present work was designed to assess the potential hemato-biochemical protective action, immunemodulatory and antioxidant conclusions of varied concentration of white mulberry Morus alba leaves (MAL) extract supplementation on Nile tilapia (Oreochromis .niloticus). A total two hundred and forty of O. niloticus were haphazardly sorted into four groups. The control (CT) group was fed on basal diet. A group MAL(1), MAL(3) and MAL(5) was fed on 1, 3 and 5 g/kg MAL respectively for thirty days. On day thirty one, half of replicates in each group were challenged by 0.5 ml x 10(8) Aeromonas hydrophila where, the residual replicates were kept without challenge. A. hydrophila challenged tilapias revealed anemia that alleviated by supplementation with 5 g/kg MAL also, recovers the shift of leucogram prompted by the challenge. Elevation of alkaline phosphatase, aminotransferases, lactate dehydrogenase and malondialdehyde (ALP, ALT, AST, LDH and MDA) in CT, MAL(1) and MAL(3) in the challenged replicates respectively where within normal at MAL(5). Supplementation with MAL(5) showed more potent antioxidant and immune reaction than MAL(1) and MAL(3). There were a rapid increase of immunoglobulin M, lysozymes, nitric oxide, catalase and superoxide dismutase and their allied genes expression (IgM, CAT and SOD) in MAL groups with contrast in CT challenged groups. Where in challenged groups, there was suppression in genes expression of interleukins (8 and 1 beta) and interferon gamma (IL8. IL-1 beta and INF gamma). Tilapias challenged by A. hydrophila unveiled plentiful surge in the percentage of mortality in CT challenged fish (80%), followed by the groups supplemented with MAL(1) and MAL(3) were (73.33%) where MAL(5) was 20%. The mortalities have been halted from the 6th, 13th, 14th and 15th days in, MAL(5), MAL(3), MAL(1), and CT correspondingly. These previous results could be fulfilled that using of MAL 5 g/kg protect tilapias from hemato-biochemical alterations and enhance it

关键词： Metal homeostasis   Methanol dehydrogenase   Lanmodulin   Lanthanome   Metallophores   Metal uptake   Rare earth elements   Methylotroph  

摘要： Lanthanides are relative newcomers to the field of cell biology of metals;their specific incorporation into enzymes was only demonstrated in 2011, with the isolation of a bacterial lanthanide- and pyrroloquinoline quinone-dependent methanol dehydrogenase. Since that discovery, the efforts of many investigators have revealed that lanthanide utilization is widespread in environmentally important bacteria, and parallel efforts have focused on elucidating the molecular details involved in selective recognition and utilization of these metals. In this review, we discuss the particular chemical challenges and advantages associated with biology's use of lanthanides, as well as the currently known lanthano-enzymes and -proteins (the lanthanome). We also review the emerging understanding of the coordination chemistry and biology of lanthanide acquisition, trafficking, and regulatory pathways. These studies have revealed significant parallels with pathways for utilization of other metals in biology. Finally, we discuss some of the many unresolved questions in this burgeoning field and their potentially far-reaching applications.

关键词： Ecotoxicology   Industrial pollution   Occupational health   Liver   Hepatotoxicity   Oxidative stress  

摘要： The aim of this experimental study was to investigate hepatotoxicity effects of noise and toluene, and in particular, to study hepatotoxicity effects of simultaneous exposure to noise and toluene by histopathological and biochemical experiments. To experiment hepatotoxicity effects of noise and toluene, 100 dB white noise and 1000 ppm toluene vapors were generated during two consecutive weeks in healthy male New Zealand White rabbits. Non-simultaneous exposure to noise and toluene increased liver enzymes and the serum levels ofsuperoxide dismutase, malondialdehyde, and total antioxidant capacity, and also decreased serum level of glutathione peroxidase. Alanine transaminase, aspartate transaminase, gamma-glutamyl transferase, malondialdehyde, total antioxidant capacity, and superoxide dismutase levels increased by simultaneous exposure to noise and toluene. Furthermore, catalase and alkaline phosphatase level decreased by simultaneous exposure to noise and toluene. The hematoxylin and eosin stain (H&E) experiments indicated significant swelling, lipidosis, eosinophilic cytoplasm, pyknosis, karyorrhexis, and disruption of the cytoplasmic membrane in the liver tissue due to exposure to noise, toluene and simultaneous exposure to them. [GRAPHICS] .

关键词： Proteomics   Isobaric labelling   Tandem mass tag (TMT)   Biomarkers   Flame retardants   Marine mussels  

摘要： Organophosphate flame retardants (OPFRs) are (re-)emergent environmental pollutants increasingly being used because of the restriction of other flame retardants. The chlorinated OPFR, tris(1,3-dichloro-2-propyl) phosphate (TDCPP) is among those of highest environmental concern, but its potential effects in the marine environment have rarely been investigated. We exposed a widely used sentinel marine mussel species, Mytilus galloprovincialis, to 10 mu g L-1 of TDCPP during 28 days and studied: (i) the kinetics of bioaccumulation and elimination of the compound, (ii) the effect on two molecular biomarkers, glutathione S-transferase (GST) and acetylcholinesterase (AChE) activities, and (iii) proteomic alterations in the gills, following an isobaric labeling quantitative shotgun proteomic approach, at two exposure times (7 and 28 days). Uptake and elimination of TDCPP by mussels were very fast, and the bioconcentration factor of this compound in mussels was 147 L kg(ww)(-1), confirming that this compound is not very bioaccumulative, as predicted by its chemical properties. GST activity was not affected by TDCPP exposure, but AChE activity was inhibited by TDCPP at both 7 and 28 days of exposure. Proteomic analysis revealed subtle effects of TDCPP in mussel gills, since few proteins (less than 2 % of the analysed proteome) were significantly affected by TDCPP, and effect sizes were low. The most relevant effects detected were the up-regulation of epimerase family protein SDR39U1, an enzyme that could be involved in detoxification processes, at both exposure times, and the down-regulation of receptor-type tyrosine-protein phosphatase N2-like (PTPRN2) after 7 days of exposure, which is involved in neurotransmitter secretion and might be related to the neurotoxicity described for this compound. Exposure time rather than TDCPP exposure was the most important driver of protein abundance changes, with 33 % of the proteome being affected by this factor, suggesting that stress c

关键词： Fructosyltransferase   Aspergillus   Immobilization   Silica gel   Enzymatic characterization  

摘要： Objective Extracellular fructosyltransferase (FTase, E.C.2.***.1.9) fromAspergillus oryzaeIPT-301 was immobilized on silica gel by adsorption and biochemically characterized aiming at its application in the transfructosylation reaction of sucrose for the production of fructooligossaccarides (FOS). Results The transfructosylation activity (A(T)) was maximized by the experimental design in function of the reaction pHs and temperatures. The A(T)of the immobilized enzyme showed the kinetics behavior described by the Hill model. The immobilized FTase showed reuse capacity for six consecutive reaction cycles and higher pH and thermal stability than the soluble enzyme. Conclusion These results suggest a high potential of application of silica gel as support for FTase immobilization aiming at FOS production.

关键词： mononuclear Fe(II) α-ketoglutarate dependent dioxygenase   structure function   crystallography   stoichiometry   molecular dynamics   enzyme mechanism  

摘要： The isonitrile moiety is found in marine sponges and some microbes, where it plays a role in processes such as virulence and metal acquisition. Until recently only one route was known for isonitrile biosynthesis, a condensation reaction that brings together a nitrogen atom of L-Trp/L-Tyr with a carbon atom from ribulose-5-phosphate. With the discovery of ScoE, a mononuclear Fe(II) alpha-ketoglutarate-dependent dioxygenase from Streptomyces coeruleorubidus, a second route was identified. ScoE forms isonitrile from a glycine adduct, with both the nitrogen and carbon atoms coming from the same glycyl moiety. This reaction is part of the nonribosomal biosynthetic pathway of isonitrile lipopeptides. Here, we present structural, biochemical, and computational investigations of the mechanism of isonitrile formation by ScoE, an unprecedented reaction in the mononuclear Fe(II) alpha-ketoglutarate-dependent dioxygenase superfamily. The stoichiometry of this enzymatic reaction is measured, and multiple high-resolution (1.45-1.96 angstrom resolution) crystal structures of Fe(II)-bound ScoE are presented, providing insight into the binding of substrate, (R)-3-((carboxylmethyl)amino)butanoic acid (CABA), cosubstrate alpha-ketoglutarate, and an Fe(IV)=O mimic oxovanadium. Comparison to a previously published crystal structure of ScoE suggests that ScoE has an "inducible" alpha-ketoglutarate binding site, in which two residues arginine-157 and histidine-299 move by approximately 10 angstrom from the surface of the protein into the active site to create a transient alpha-ketoglutarate binding pocket. Together, data from structural analyses, site-directed mutagenesis, and computation provide insight into the mode of alpha-ketoglutarate binding, the mechanism of isonitrile formation, and how the structure of ScoE has been adapted to perform this unusual chemical reaction.

关键词： Prostate cancer   Neoplasm recurrence   Local   Positron emission tomography computed tomography   Radioisotopes   Gallium   Prostate-specific membrane antigen   Human   Biochemical recurrence   Salvage Treatments  

摘要： Rationale: Ga-68-prostate-specific membrane antigen positron emission tomography/computed tomography (PET-PSMA) has shown promising performance for the assessment of biochemical recurrence of prostate cancer in high-risk patients, defined by D'Amico et al. criteria. Little evidence for the impact of this diagnostic method for patients at low or intermediate risk, in terms of management and benefits of subsequent treatment, is available. Methods: Data from 57 patients with low and intermediate-risk prostate cancer and biochemical recurrence underwent PET-PSMA were examined retrospectively. Images were analyzed and findings were compared with clinical data. Indications for the PET-PSMA imaging, study positivity/negativity, lesion locations, Gleason (ISUP) score, prostate-specific antigen (PSA) level on the examination date, postexamination treatment, and management were evaluated. Results: PET-PSMA findings were negative for 28 (49.12%) patients, 11 of whom received salvage radiotherapy (S-RT;with or without HT;PSA levels declined significantly in 10 (90.9%) of these patients compared with levels in those not undergoing S-RT. Positive PET-PSMA findings enabled the accurate identification of patients who benefited from salvage pelvic RT for local disease control and those who responded satisfactorily to systemic treatment. Conclusion: PET-PSMA is useful for the assessment of biochemical recurrence in prostate cancer patients with prostate cancer at low and intermediate-risk. (C) 2020 Elsevier Inc. All rights reserved.

关键词： Apoptosis   Histopathology   Lipid peroxidation   Morphometry   Nandrolone decanoate   Prostate   Seminal vesicles  

摘要： Nandrolone decanoate (Nd) is a highly abused androgenic-anabolic steroid among body builders. Even though it has weak androgenic effects, its prolonged use may have harmful impact on male reproductive system which needs to be evaluated. This study aimed to reinvestigate its possible oxidative stress induced alteration on male rat reproductive system. Twenty-eight male rats were divided into two groups. Nd treated group (n = 18) injected intramuscular with 10 mg/kg body weight once a week for four weeks. While, the control group (n = 10) was injected with physiologic saline by the same route for four weeks. Body weight was recorded for all rats and after animal dissection weight of testes, prostate and seminal vesicles were also recorded. The results showed that the average testicular weight was decreased in treated group compared to the control. The average weights of the prostate and seminal vesicles were increased compared to the control. Morphometric study revealed that in Nd treated group, there was a decrease in the width of seminiferous tubules and the height of spermatogenic cell layer compared to the control. Testicular degeneration was expressed by presence of spermatid giant cells, vacuolation, and degenerated spermatozoa. Tunnel technique showed scattered positive reaction among the spermatogenic cell layers and interstitial cells. Severe alterations of the prostate were expressed by benign prostate hyperplasia and retained secretions. Lipid peroxidation products (malonaldehyde concentration as ng/g of testicular tissue) were increased in treated group compared to the control and suggested the occurrence of oxidative damage. Nd induced severe alterations in the male genital organs were resulted from oxidative stress. It is concluded that the male genital organs are highly sensitive to the anabolic steroids and there is a high extent of reproductive risk associated with the use of AASs. (C) 2020 The Author. Published by Elsevier B.V. on behalf of King Saud

关键词： Monofloral honey   Phytochemicals   Total anti-oxidant activity   Valued products   Chemometrics  

摘要： The effects of iron and copper on the total in vitro anti-oxidant activity of Hellenic monofloral honeys (citrus, fir, pine, and thyme) under the presence of phytochemicals were presented for the first time in the literature. Authenticity issues were also investigated using supervised statistical techniques on the data set measured which consisted of effective acidity (pH), color intensity (brown pigments), in vitro anti-oxidant activity, total phytochemical content, copper (Cu), and iron (Fe) contents. Results showed that in vitro anti-oxidant activity was positively correlated (p < 0.05) with total phytochemical, copper, and iron contents, along with color intensity and pH in relation to honey botanical origin. Therefore, new terms as those of "total anti-oxidant activity'' and "total phytochemical content'' may be proposed to describe the antioxidant activity developed under the presence of phytochemicals and catalytic minerals such as Cu and Fe. Chemometric techniques such as multivariate analysis of variance, linear discriminant analysis,k-nearest neighbors and bootstrap analyses in combination withzscore test confirmed the above theory, contributing thus, to an added value of Hellenic monofloral honey in the food chain.