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21.
Dehydrins are highly hydrophilic proteins involved in playing key adaptive roles in response to abiotic stress conditions having dehydration as a common component. In the present study, a novel banana SK(3)-type dehydrin, MusaDHN-1, was identified and later characterized using transgenic banana plants to investigate its functions in abiotic stress tolerance. Expression profiling in native banana plants demonstrated that MusaDHN-1 was induced in leaves by drought, salinity, cold, oxidative and heavy metal stress as well as by treatment with signalling molecules like abscisic acid, ethylene and methyl jasmonate. Promoter analysis carried out by making a MusaDHN-1 promoter: β-glucuronidase fusion construct reconfirmed the abiotic stress inducibility of MusaDHN-1. Transgenic banana plants constitutively overexpressing MusaDHN-1 were phenotypically normal and displayed improved tolerance to drought and salt-stress treatments in both in vitro and ex vitro assays. Enhanced accumulation of proline and reduced malondialdehyde levels in drought and salt-stressed MusaDHN-1 overexpressing plants further established their superior performance in stressed conditions. This study is the first to report generation of transgenic banana plants engineered for improved drought and salt-stress tolerance. 相似文献
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Nicola J. Robertson Christopher Meehan Kathryn A. Martinello Adnan Avdic-Belltheus Tiziana Boggini Tatenda Mutshiya Ingran Lingam Qin Yang Magdalena Sokolska Xenia Charalambous Alan Bainbridge Mariya Hristova Boris W. Kramer Xavier Golay Ben Weil Mark W. Lowdell 《Cytotherapy》2021,23(6):521-535
Background: With therapeutic hypothermia (HT) for neonatal encephalopathy, disability rates are reduced, but not all babies benefit. Pre-clinical rodent studies suggest mesenchymal stromal cells (MSCs) augment HT protection. Aims:The authors studied the efficacy of intravenous (IV) or intranasal (IN) human umbilical cord-derived MSCs (huMSCs) as adjunct therapy to HT in a piglet model. Methods:A total of 17 newborn piglets underwent transient cerebral hypoxia-ischemia (HI) and were then randomized to (i) HT at 33.5°C 1–13 h after HI (n = 7), (ii) HT+IV huMSCs (30 × 106 cells) at 24 h and 48 h after HI (n = 5) or (iii) HT+IN huMSCs (30 × 106 cells) at 24 h and 48 h after HI (n = 5). Phosphorus-31 and hydrogen-1 magnetic resonance spectroscopy (MRS) was performed at 30 h and 72 h and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL)-positive cells and oligodendrocytes quantified. In two further piglets, 30 × 106 IN PKH-labeled huMSCs were administered. Results:HI severity was similar between groups. Amplitude-integrated electroencephalogram (aEEG) recovery was more rapid for HT+IN huMSCs compared with HT from 25 h to 42 h and 49 h to 54 h (P ≤ 0.05). MRS phosphocreatine/inorganic phosphate was higher on day 2 in HT+IN huMSCs than HT (P = 0.035). Comparing HT+IN huMSCs with HT and HT+IV huMSCs, there were increased OLIG2 counts in hippocampus (P = 0.011 and 0.018, respectively), internal capsule (P = 0.013 and 0.037, respectively) and periventricular white matter (P = 0.15 for IN versus IV huMSCs). Reduced TUNEL-positive cells were seen in internal capsule with HT+IN huMSCs versus HT (P = 0.05). PKH-labeled huMSCs were detected in the brain 12 h after IN administration. Conclusions:After global HI, compared with HT alone, the authors saw beneficial effects of HT+IN huMSCs administered at 24 h and 48 h (30 × 106 cells/kg total dose) based on more rapid aEEG recovery, improved 31P MRS brain energy metabolism and increased oligodendrocyte survival at 72 h. 相似文献
23.
Catechol 2, 3-dioxygenase is present in several types of bacteria and undergoes degradation of environmental pollutants through
an important key biochemical pathways. Specifically, this enzyme cleaves aromatic rings of several environmental pollutants such
as toluene, xylene, naphthalene and biphenyl derivatives. Hence, the importance of Catechol 2, 3-dioxygenase and its role in the
degradation of environmental pollutants made us to predict the three-dimensional structure of Catechol 2, 3-dioxygenase from
Burkholderia cepacia. The 10ns molecular dynamics simulation was carried out to check the stability of the modeled Catechol 2, 3-
dioxygenase. The results show that the model was energetically stable, and it attains their equilibrium within 2000 ps of production
MD run. The docking of various petroleum hydrocarbons into the Catechol 2,3-dioxygenase reveals that the benzene, O-xylene,
Toluene, Fluorene, Naphthalene, Carbazol, Pyrene, Dibenzothiophene, Anthracene, Phenanthrene, Biphenyl makes strong
hydrogen bond and Van der waals interaction with the active site residues of H150, L152, W198, H206, H220, H252, I254, T255,
Y261, E271, L276 and F309. Free energy of binding and estimated inhibition constant of these compounds demonstrates that they
are energetically stable in their binding cavity. Chrysene shows positive energy of binding in the active site atom of Fe. Except
Pyrene all the substrates made close contact with Fe atom by the distance ranges from 1.67 to 2.43 Å. In addition to that, the above
mentioned substrate except pyrene all other made π-π stacking interaction with H252 by the distance ranges from 3.40 to 3.90 Å.
All these docking results reveal that, except Chrysene all other substrate has good free energy of binding to hold enough in the
active site and makes strong VdW interaction with Catechol-2,3-dioxygenase. These results suggest that, the enzyme is capable of
catalyzing the above-mentioned substrate. 相似文献
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Cleide G da Silva César A J Ribeiro Guilhian Leipnitz Carlos S Dutra-Filho Angela T S Wyse AT Clóvis M D Wannmacher Jo?o J F Sarkis Cornelis Jakobs Moacir Wajner 《Biochimica et biophysica acta》2002,1586(1):81-91
L-2-Hydroxyglutaric (LGA) and D-2-hydroxyglutaric (DGA) acids are the characteristic metabolites accumulating in the neurometabolic disorders known as L-2-hydroxyglutaric aciduria and D-2-hydroxyglutaric aciduria, respectively. Although these disorders are predominantly characterized by severe neurological symptoms, the neurotoxic mechanisms of brain damage are virtually unknown. In this study we have evaluated the role of LGA and DGA at concentrations ranging from 0.01 to 5.0 mM on various parameters of energy metabolism in cerebral cortex slices and homogenates of 30-day-old Wistar rats, namely glucose uptake, CO(2) production and the respiratory chain enzyme activities of complexes I to IV. DGA significantly decreased glucose utilization (2.5 and 5.0 mM) by brain homogenates and CO(2) production (5 mM) by brain homogenates and slices, whereas LGA had no effect on either measurement. Furthermore, DGA significantly inhibited cytochrome c oxidase activity (complex IV) (EC 1.9.3.1) in a dose-dependent manner (35-95%) at doses as low as 0.5 mM, without compromising the other respiratory chain enzyme activities. In contrast, LGA did not interfere with these activities. Our results suggest that the strong inhibition of cytochrome c oxidase activity by increased levels of DGA could be related to the neurodegeneration of patients affected by D-2-hydroxyglutaric aciduria. 相似文献
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Background
Plasmodium falciparum antigenic diversity and polymorphism confuses the issue of antimalarial vaccine development. Merozoite surface protein (MSP)-1 and -2 are two highly polymorphic vaccine candidates. Characterisation of their precise polymorphism in endemic regions may facilitate the design of an effective vaccine.Methods
Isolates obtained in 52 Gabonese children presenting with uncomplicated malaria were genotyped by nested-PCR of msp -1 block 2, and msp -2 block 3, to analyze both parasite population polymorphism and clone fluctuations.Results
Twenty-five and 19 different alleles were respectively obtained for msp-1 and msp-2 loci, the RO33 family of msp-1 being poorly polymorphic. Four cases of non-random distribution of alleles were reported of the FC27, and/or 3D7 families of msp-2. All but two isolates were composed of more than one genotype, and the multiplicity of infection (MOI) was 4.0. Neither parasite density nor age was related to MOI. Clone fluctuations were studied for ten subjects who were sampled again at reappearance of parasites in blood. Disappearance and reappearance of alleles were observed following treatment, suggesting difficulties in assessing polymorphism and in distinguishing reinfection from recrudescence.Conclusion
P. falciparum polymorphism is extensive in Southeast Gabon, and most of infections are composed of multiple clones. The fluctuation of clones contributes to parasite diversity. 相似文献28.
Malgorzata Cyranka Anna Veprik Eleanor J. McKay Nienke van Loon Amber Thijsse Luke Cotter Nisha Hare Affan Saibudeen Swathi Lingam Elisabete Pires Pierre Larraufie Frank Reimann Fiona Gribble Michelle Stewart Elizabeth Bentley Pamela Lear James McCullagh James Cantley Roger D. Cox Heidi de Wet 《Obesity (Silver Spring, Md.)》2019,27(8):1292-1304
29.
Kim AT Verheijden Linette EM Willemsen Saskia Braber Thea Leusink-Muis Dianne JM Delsing Johan Garssen Aletta D Kraneveld Gert Folkerts 《Respiratory research》2015,16(1)
Background
Allergic asthma is strongly associated with the exposure to house dust mite (HDM) and is characterized by eosinophilic pulmonary inflammation and airway hyperresponsiveness (AHR). Recently, there is an increased interest in using dietary oligosaccharides, also known as prebiotics, as a novel strategy to prevent the development of, or reduce, symptoms of allergy.Aim
We investigated the preventive capacity of dietary galacto-oligosaccharides (GOS) compared to an intra-airway therapeutic treatment with budesonide on the development of HDM-induced allergic asthma in mice.Methods
BALB/c mice were intranasally sensitized with 1 μg HDM on day 0 followed by daily intranasal challenge with PBS or 10 μg HDM on days 7 to 11. Two weeks prior to the first sensitization and throughout the experiment mice were fed a control diet or a diet containing 1% GOS. Reference mice were oropharyngeally instilled with budesonide (500 μg/kg) on days 7, 9, 11, and 13, while being fed the control diet. On day 14, AHR was measured by nebulizing increasing doses of methacholine into the airways. At the end of the experiment, bronchoalveolar lavage fluid (BALF) and lungs were collected.Results
Sensitization and challenge with HDM resulted in AHR. In contrast to budesonide, dietary intervention with 1% GOS prevented the development of AHR. HDM sensitization and challenge resulted in a significant increase in BALF leukocytes numbers, which was suppressed by budesonide treatment and dietary intervention with 1% GOS. Moreover, HDM sensitization and challenge resulted in significantly enhanced concentrations of IL-6, CCL17, IL-33, CCL5 and IL-13 in lung tissue. Both dietary intervention with 1% GOS or budesonide treatment significantly decreased the HDM-induced increased concentrations of CCL5 and IL-13 in lung tissue, while budesonide also reduced the HDM-enhanced concentrations of IL-6 and CCL17 in lung tissue.Conclusion
Not only did dietary intervention with 1% GOS during sensitization and challenge prevent the induction of airway eosinophilia and Th2-related cytokine and chemokine concentrations in the lung equally effective as budesonide treatment, it also prevented AHR development in HDM-allergic mice. GOS might be useful for the prevention and/or treatment of symptoms in asthmatic disease.Electronic supplementary material
The online version of this article (doi:10.1186/s12931-015-0171-0) contains supplementary material, which is available to authorized users. 相似文献30.
Jennifer L Percival-Alwyn Elizabeth England Benjamin Kemp Laura Rapley Nicola HE Davis Grant R McCarthy Jayesh B Majithiya Dominic J Corkill Sarah Welsted Kevin Minton E Suzanne Cohen Matthew J Robinson Claire Dobson Trevor CI Wilkinson Tristan J Vaughan Maria AT Groves Natalie J Tigue 《MABS-AUSTIN》2015,7(1):129-137
Immunization of mice or rats with a "non-self" protein is a commonly used method to obtain monoclonal antibodies, and relies on the immune system''s ability to recognize the immunogen as foreign. Immunization of an antigen with 100% identity to the endogenous protein, however, will not elicit a robust immune response. To develop antibodies to mouse proteins, we focused on the potential for breaking such immune tolerance by genetically fusing two independent T-cell epitope-containing sequences (from tetanus toxin (TT) and diphtheria toxin fragment A (DTA)) to a mouse protein, mouse ST2 (mST2). Wild-type CD1 mice were immunized with three mST2 tagged proteins (Fc, TT and DTA) and the specific serum response was determined. Only in mice immunized with the T-cell epitope-containing antigens were specific mST2 serum responses detected; hybridomas generated from these mice secreted highly sequence-diverse IgGs that were capable of binding mST2 and inhibiting the interaction of mST2 with its ligand, mouse interleukin (IL)-33 (mIL-33). Of the hundreds of antibodies profiled, we identified five potent antibodies that were able to inhibit IL-33 induced IL-6 release in a mast cell assay; notably one such antibody was sufficiently potent to suppress IL-5 release and eosinophilia infiltration in an Alternaria alternata challenge mouse model of asthma. This study demonstrated, for the first time, that T-cell epitope-containing tags have the ability to break tolerance in wild-type mice to 100% conserved proteins, and it provides a compelling argument for the broader use of this approach to generate antibodies against any mouse protein or conserved ortholog. 相似文献