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991.
Olga Mogilnaya Karina Artemenko Vladimir Bondar 《Biocatalysis and Biotransformation》2019,37(2):97-105
Modified nanodiamonds (MNDs) produced by detonation synthesis can be used as an effective adsorbent to immobilize extracellular peroxidases of the luminous basidiomycete Neonothopanus nambi. The enzymes are firmly immobilized on MND particles and exhibit catalytic activity. The indicator system (the MND–enzyme complex) reused many times retains its ability to catalyze reaction of co-oxidation of phenol and 4-aminoantipirine in the presence of hydrogen peroxide and remains functionally active during long-term storage (for 1?month or longer) in aqueous suspensions at 4?°C. MNDs and enzymes of higher fungi can be effectively used to construct new reusable indicator systems for analytical applications such as monitoring contamination of aquatic environments by phenolic compounds. 相似文献
992.
Chiaki Yamada Camila Beron‐Pelusso Neira Algazzaz Alireza Heidari Diogo Luz Mutasem Rawas‐Qalaji Ion Toderas Ana Karina Mascarenhas Toshihisa Kawai Alexandru Movila 《Journal of cellular and molecular medicine》2019,23(8):5827-5831
Progressive generation of total joint implant‐derived wear particles is one of the major risk factors in development of peri‐prosthetic osteolysis especially in the aging society. It is commonly accepted that macrophages predominantly drive the inflammatory response to wear debris particles. Among various surface receptors that activate the macrophages to phagocytize particles, it is believed that the Toll‐like receptor 4 (TLR4) and the scavenger macrophage receptor with collagenous structure (MARCO) play key roles in recognition of wear debris particles. However, a strong body of evidence indicates an age‐dependent diminished function of human TLRs. Thus, we hypothesized that the MARCO receptor may be more engaged than TLRs in the phagocytosis of wear debris particles which in turn up‐regulate production of pro‐inflammatory cytokines from aged macrophages. We demonstrated that peritoneal macrophages isolated from aged mice show elevated expression of MARCO receptor compared to that from young mice. In contrast the expression of TLR4 was significantly decreased on the surface of aged macrophages. Furthermore, using anti‐MARCO and anti‐TLR4 neutralizing mAbs, we demonstrated the age‐dependent pathogenic role of MARCO, but not TLR4, receptor in promoting poly‐methyl methacrylate (PMMA) bone cement particles phagocytosis by macrophages leading to the release of pro‐inflammatory cytokines migration inhibitory factor and tumour necrosis factor in vitro. These data also suggest that the approach to neutralize MARCO may lead to the development of therapeutic regimen for the prevention of particle‐induced osteolysis in aged patients. 相似文献
993.
994.
Valeria E. Perotti Alejandra S. Moreno Karina E.J. Trípodi Guillermo Meier Fernando Bello Mariángeles Cocco Daniel Vázquez Catalina Anderson Florencio E. Podestá 《Physiologia plantarum》2015,153(3):337-354
The aim of this study was to evaluate the response of orange fruit (Citrus sinensis var. Valencia Late) to freezing stress in planta, both immediately after the natural event and after a week, in order to understand the biochemical and molecular basis of the changes that later derive in internal and external damage symptoms. Using two‐dimensional differential gel electrophoresis to analyze exposed and non‐exposed fruit, 27 differential protein spots were detected in juice sacs and flavedo, among all comparisons made. Also, primary and secondary metabolites relative contents were analyzed in both tissues by gas chromatography‐mass spectrometry and liquid chromatography‐mass spectrometry, respectively. Proteins and compounds involved in regulatory functions, iron metabolism, oxidative damage and carbohydrate metabolism were the most affected. Interestingly, three glycolytic enzymes were induced by cold, and there was an increase in fermentation products (volatiles); all of that suggests that more energy generation might be required from glycolysis to counter the cold stress. Moreover, a notable increase in sugar levels was observed after frost, but it was not at the expense of organic acids utilization. Consequently, these results suggest a probable redistribution of photoassimilates in the frost‐exposed plants, tending to restore the homeostasis altered by that severe type of stress. Isosinensetin was the most cold‐sensitive secondary metabolite because it could not be detected at all after the frost, constituting a possible tool to early diagnose freezing damage. 相似文献
995.
Karina Krzciuk 《Critical reviews in biotechnology》2015,35(4):522-532
Specific plant species that can take up and accumulate abnormally high concentrations of elements in their aboveground tissues are referred to as “hyperaccumulators”. The use of this term is justified in the case of enormous element-binding capacity of plants growing in their natural habitats and showing no toxicity symptoms. An increasing interest in the study of hyperaccumulators results from their potential applications in environmental biotechnology (phytoremediation, phytomining) and their emerging role in nanotechnology. The highest number of plant species with confirmed hyperaccumulative properties has been reported for hyperaccumulators of nickel, cadmium, zinc, manganese, arsenic and selenium. More limited data exist for plants accumulating other elements, including common pollutants (chromium, lead and boron) or elements of commercial value, such as copper, gold and rare earth elements. Different approaches have been used for the study of hyperaccumulators – geobotanical, chemical, biochemical and genetic. The chemical approach is the most important in screening for new hyperaccumulators. This article presents and critically reviews current trends in new hyperaccumulator research, emphasizing analytical methodology that is applied in identification of new hyperaccumulators of trace elements and its future perspectives. 相似文献
996.
997.
Genetic analysis of the ‘uveal melanoma’ C918 cell line reveals atypical BRAF and common KRAS mutations and single tandem repeat profile identical to the cutaneous melanoma C8161 cell line
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998.
Immunological blockade of adipocyte inflammation caused by increased matrix metalloproteinase‐cleaved osteopontin in obesity
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999.
Marquiza Sablón-Carrazana Isaac Fernández Alberto Bencomo Reyna Lara-Martínez Suchitil Rivera-Marrero Guadalupe Domínguez Rafaela Pérez-Perera Luis Felipe Jiménez-García Nelly F. Altamirano-Bustamante Massiel Diaz-Delgado Fernand Vedrenne Lina Rivillas-Acevedo Karina Pasten-Hidalgo María de Lourdes Segura-Valdez Sergio Islas-Andrade Eulalia Garrido-Maga?a Alejandro Perera-Pintado Anaís Prats-Capote Chryslaine Rodríguez-Tanty Myriam M. Altamirano-Bustamante 《PloS one》2015,10(9)
The increasing prevalence of conformational diseases, including Alzheimer''s disease, type 2 Diabetes Mellitus and Cancer, poses a global challenge at many different levels. It has devastating effects on the sufferers as well as a tremendous economic impact on families and the health system. In this work, we apply a cross-functional approach that combines ideas, concepts and technologies from several disciplines in order to study, in silico and in vitro, the role of a novel chemical chaperones family (NCHCHF) in processes of protein aggregation in conformational diseases. Given that Serum Albumin (SA) is the most abundant protein in the blood of mammals, and Bovine Serum Albumin (BSA) is an off-the-shelf protein available in most labs around the world, we compared the ligandability of BSA:NCHCHF with the interaction sites in the Human Islet Amyloid Polypeptide (hIAPP):NCHCHF, and in the amyloid pharmacophore fragments (Aβ17–42 and Aβ16–21):NCHCHF. We posit that the merging of this interaction sites is a meta-structure of pharmacophore which allows the development of chaperones that can prevent protein aggregation at various states from: stabilizing the native state to destabilizing oligomeric state and protofilament. Furthermore to stabilize fibrillar structures, thus decreasing the amount of toxic oligomers in solution, as is the case with the NCHCHF. The paper demonstrates how a set of NCHCHF can be used for studying and potentially treating the various physiopathological stages of a conformational disease. For instance, when dealing with an acute phase of cytotoxicity, what is needed is the recruitment of cytotoxic oligomers, thus chaperone F, which accelerates fiber formation, would be very useful; whereas in a chronic stage it is better to have chaperones A, B, C, and D, which stabilize the native and fibril structures halting self-catalysis and the creation of cytotoxic oligomers as a consequence of fiber formation. Furthermore, all the chaperones are able to protect and recondition the cerebellar granule cells (CGC) from the cytotoxicity produced by the hIAPP20–29 fragment or by a low potassium medium, regardless of their capacity for accelerating or inhibiting in vitro formation of fibers. In vivo animal experiments are required to study the impact of chemical chaperones in cognitive and metabolic syndromes. 相似文献
1000.
Thyago Hermylly Santana Cardoso Ana Camila Oliveira Freitas Bruno Silva Andrade Aurizangela Oliveira de Sousa André da Silva Santiago Daniela Martins Koop Karina Peres Gramacho Fátima Cerqueira Alvim Fabienne Micheli Carlos Priminho Pirovani 《PloS one》2015,10(12)
The interaction amongst papain-like cysteine-proteases (PLCP) and their substrates and inhibitors, such as cystatins, can be perceived as part of the molecular battlefield in plant-pathogen interaction. In cacao, four cystatins were identified and characterized by our group. We identified 448 proteases in cacao genome, whereof 134 were cysteine-proteases. We expressed in Escherichia coli a PLCP from cacao, named TcCYSPR04. Immunoblottings with anti-TcCYSPR04 exhibited protein increases during leaf development. Additional isoforms of TcCYSPR04 appeared in senescent leaves and cacao tissues infected by Moniliophthora perniciosa during the transition from the biotrophic to the saprophytic phase. TcCYSPR04 was induced in the apoplastic fluid of Catongo and TSH1188 cacao genotypes, susceptible and resistant to M. perniciosa, respectively, but greater intensity and additional isoforms were observed in TSH1188. The fungal protein MpNEP induced PLCP isoform expression in tobacco leaves, according to the cross reaction with anti-TcCYSPR04. Several protein isoforms were detected at 72 hours after treatment with MpNEP. We captured an active PLCP from cacao tissues, using a recombinant cacao cystatin immobilized in CNBr-Sepharose. Mass spectrometry showed that this protein corresponds to TcCYSPR04. A homology modeling was obtained for both proteins. In order to become active, TcCYSPR04 needs to lose its inhibitory domain. Molecular docking showed the physical-chemical complementarities of the interaction between the cacao enzyme and its inhibitor. We propose that TcCYSPR04 and its interactions with cacao cystatins are involved in the senescence and necrosis events related to witches’ broom symptoms. This molecular interaction may be the target for future interventions to control witches'' broom disease. 相似文献