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991.
Boubaker Nouha Setti Spagnuolo Manuela Trabelsi Nesrine Said Rahma Gurtner Aymone Regazzo Giulia Ayed Haroun Blel Ahlem Karray Omar Saadi Ahmed Rammeh Soumaya Chebil Mohamed Rizzo Maria Giulia Piaggio Giulia Ouerhani Slah 《Molecular biology reports》2020,47(2):1283-1292
Molecular Biology Reports - Hsa-mir-143 and hsa-let-7c have been reported to be deregulated in multiple neoplasms. The main purpose of this study was to investigate the expression of these miRNAs... 相似文献
992.
Alessia Leonetti Giulia Baroli Emiliano Fratini Stefano Pietropaoli Manuela Marcoli Paolo Mariottini Manuela Cervelli 《Amino acids》2020,52(2):129-139
Several studies have demonstrated high polyamine levels in brain diseases such as epilepsy. Epilepsy is the fourth most common neurological disorder and affects people of all ages. Excitotoxic stress has been associated with epilepsy and it is considered one of the main causes of neuronal degeneration and death. The transgenic mouse line Dach-SMOX, with CD1 background, specifically overexpressing spermine oxidase in brain cortex, has been proven to be highly susceptible to epileptic seizures and excitotoxic stress induced by kainic acid. In this study, we analysed the effect of spermine oxidase over-expression in a different epileptic model, pentylenetetrazole. Behavioural evaluations of transgenic mice compared to controls showed a higher susceptibility towards pentylentetrazole. High-performance liquid chromatography analysis of transgenic brain from treated mice revealed altered polyamine content. Immunoistochemical analysis indicated a rise of 8-oxo-7,8-dihydro-2′-deoxyguanosine, demonstrating an increase in oxidative damage, and an augmentation of system xc− as a defence mechanism. This cascade of events can be initially linked to an increase in protein kinase C alpha, as shown by Western blot. This research points out the role of spermine oxidase, as a hydrogen peroxide producer, in the oxidative stress during epilepsy. Moreover, Dach-SMOX susceptibility demonstrated by two different epileptic models strongly indicates this transgenic mouse line as a potential animal model to study epilepsy. 相似文献
993.
Kollmus Heike Fuchs Helmut Lengger Christoph Haselimashhadi Hamed Bogue Molly A. stereicher Manuela A. Horsch Marion Adler Thure Aguilar-Pimentel Juan Antonio Amarie Oana Veronica Becker Lore Beckers Johannes Calzada-Wack Julia Garrett Lillian Hans Wolfgang Hlter Sabine M. Klein-Rodewald Tanja Maier Holger Mayer-Kuckuk Philipp Miller Gregor Moreth Kristin Neff Frauke Rathkolb Birgit Rcz Ildik Rozman Jan Spielmann Nadine Treise Irina Busch Dirk Graw Jochen Klopstock Thomas Wolf Eckhard Wurst Wolfgang Yildirim Ali nder Mason Jeremy Torres Arturo Balling Rudi Mehaan Terry Gailus-Durner Valerie Schughart Klaus Hrab de Angelis Martin 《Mammalian genome》2020,31(1):30-48
Mammalian Genome - The collaborative cross (CC) is a large panel of mouse-inbred lines derived from eight founder strains (NOD/ShiLtJ, NZO/HILtJ, A/J, C57BL/6J, 129S1/SvImJ, CAST/EiJ, PWK/PhJ, and... 相似文献
994.
995.
Stirpe A Pantusa M Rizzuti B Sportelli L Bartucci R Guzzi R 《International journal of biological macromolecules》2011,49(3):337-342
The heat induced aggregation of human serum albumin (HSA) with and without an equimolar amount of Cu(II) and Zn(II) was investigated by using optical absorption, fluorescence, AFM and EPR spectroscopy. Turbidity experiments as a function of temperature indicate that the protein aggregation occurs after the melting of the protein. The kinetic of HSA aggregation, investigated between 60 and 70 °C by monitoring the optical density changes at 400 nm on a 180 min time window, shows an exponential growth with a rate that increases with the temperature. Fluorescence of the thioflavin T evidences a significant increase of the intensity at 480 nm at increasing incubation time. These results combined with AFM experiments show that the protein aggregates are elongated oligomers with fibrillar-like features. The absence of a lag-phase suggests that the early stage aggregation of HSA follows a downhill pathway that does not require the formation of an organized nucleus. The presence of Cu(II) and Zn(II) ions does not affect the thermally induced aggregation process and the morphology of HSA aggregates. The result is compatible with the binding of the metal ions to the protein in the native state and with the high conformational stability of HSA. 相似文献
996.
Sammarco ML Vitullo M Tamburro M Pontello M Ripabelli G 《Journal of microbiological methods》2011,87(1):119-124
Fifty Listeria monocytogenes strains were genotyped by sAFLP and PCR products were separated by agarose gel and automated chip-based microfluidic electrophoresis. A high congruency of results was observed comparing the two techniques, although for some cultures a better separation of sAFLP fragments was achieved with microfluidic system, which proved to be a highly reliable and reproducible tool to improve the molecular typing of L. monocytogenes, requiring lower volumes of samples and reducing significantly analysis time. 相似文献
997.
Whey protein concentrate (WPC) was subjected to enzymatic hydrolysis by proteases from the flowers of Cynara cardunculus, and the resulting angiotensin-converting enzyme (ACE)-inhibitory effect was monitored. The whole WPC hydrolysate exhibited an IC50 value of 52.9 ± 2.9 μg/mL, whereas the associated peptide fraction with molecular weight below 3 kDa scored 23.6 ± 1.1 μg/mL. The latter fraction was submitted to RP-HPLC, and 6 fractions were resolved that exhibited ACE-inhibitory effects. Among the various peptides found, a total of 14 were identified via sequencing with an ion-trap mass spectrometer. Eleven of these peptides were synthesized de novo - to validate their ACE-inhibitory effect, and also to ascertain their stability when exposed to simulated gastrointestinal digestion. Among them, three novel, highly potent peptides were found, corresponding to α-lactalbumin f(16-26) - with the sequence KGYGGVSLPEW, α-lactalbumin f(97-104) with DKVGINYW, and β-lactoglobulin f(33-42) with DAQSAPLRVY; their IC50 values were as low as 0.80 ± 0.1, 25.2 ± 1.0 and 13.0 ± 1.0 μg/mL, respectively. None of them remained stable in the presence of gastrointestinal enzymes: they were partially, or even totally hydrolyzed to smaller peptides - yet the observed ACE-inhibitory effects were not severely affected for two of those peptides. 相似文献
998.
Huesgen PF Miranda H Lam X Perthold M Schuhmann H Adamska I Funk C 《The Biochemical journal》2011,435(3):733-742
Cyanobacteria require efficient protein-quality-control mechanisms to survive under dynamic, often stressful, environmental conditions. It was reported that three serine proteases, HtrA (high temperature requirement A), HhoA (HtrA homologue A) and HhoB (HtrA homologue B), are important for survival of Synechocystis sp. PCC 6803 under high light and temperature stresses and might have redundant physiological functions. In the present paper, we show that all three proteases can degrade unfolded model substrates, but differ with respect to cleavage sites, temperature and pH optima. For recombinant HhoA, and to a lesser extent for HtrA, we observed an interesting shift in the pH optimum from slightly acidic to alkaline in the presence of Mg2+ and Ca2+ ions. All three proteases formed different homo-oligomeric complexes with and without substrate, implying mechanistic differences in comparison with each other and with the well-studied Escherichia coli orthologues DegP (degradation of periplasmic proteins P) and DegS. Deletion of the PDZ domain decreased, but did not abolish, the proteolytic activity of all three proteases, and prevented substrate-induced formation of complexes higher than trimers by HtrA and HhoA. In summary, biochemical characterization of HtrA, HhoA and HhoB lays the foundation for a better understanding of their overlapping, but not completely redundant, stress-resistance functions in Synechocystis sp. PCC 6803. 相似文献
999.
Gennero L De Siena R Denysenko T Roos MA Calisti GF Martano M Fiobellot S Panzone M Reguzzi S Gabetti L Vercelli A Cavallo G Ricci E Pescarmona GP 《Cell biochemistry and function》2011,29(4):311-333
The particular combination of polydeoxyribonucleotides, l-carnitine, calcium ions, proteolytic enzyme and other ingredients acts in a synergetic way in the regeneration of skin and connective tissues. This new formulation of active principles was tested in vitro as a cell and tissue culture medium and in vivo for various preparations in support of tissue regeneration. In vitro, the new blend allowed the maintenance of skin biopsies for more than 1 year in eutrophic conditions. Immunocytochemical analyses of fibroblasts isolated from these biopsies confirmed a significant increase of the epidermal and connective wound-healing markers such as collagen type I, collagen type IV, cytokeratin 1 (CK1), CK5, CK10 and CK14 versus controls. To examine the effects of the new compound in vivo, we studied impaired wound healing in genetically diabetic db/db mice. At day 18, diabetic mice treated with the new composition showed 100% closure of wounds and faster healing than mice treated with the other solutions. This complex of vital continuity factors or life-keeping factors could be used as a tissue-preserving solution or a cosmetic/drug/medical device to accelerate wound healing in the treatment of patients with deficient wound repair to promote the regeneration of cutaneous and connective tissues (injuries-wound, dermatitis) and prevent the recurrent relapses. 相似文献
1000.
Sousa MJ Azevedo F Azevedo F Pedras A Pedras A Marques C Coutinho OP Preto A Gerós H Chaves SR Côrte-Real M 《Biochemical Society transactions》2011,39(5):1533-1537
The yeast apoptosis field emerged with the finding that key components of the apoptotic machinery are conserved in these simple eukaryotes. Thus it became possible to exploit these genetically tractable organisms to improve our understanding of the intricate mechanisms of cell death in higher eukaryotes and of severe human diseases associated with apoptosis dysfunctions. Early on, it was recognized that a mitochondria-mediated apoptotic pathway showing similarities to the mammalian intrinsic pathway was conserved in yeast. Recently, lysosomes have also emerged as central players in mammalian apoptosis. Following LMP (lysosomal membrane permeabilization), lysosomal proteases such as cathepsins B, D and L are released into the cytosol and can trigger a mitochondrial apoptotic cascade. CatD (cathepsin D) can also have anti-apoptotic effects in some cellular types and specific contexts. Nonetheless, the mechanisms underlying LMP and the specific role of cathepsins after their release into the cytosol remain poorly understood. We have recently shown that yeast vacuoles, membrane-bound acidic organelles, which share many similarities to plant vacuoles and mammalian lysosomes, are also involved in the regulation of apoptosis and that the vacuolar protease Pep4p, orthologue of the human CatD, is released from the vacuole into the cytosol in response to acetic acid. Here, we discuss how the conservation of cell-death regulation mechanisms in yeast by the lysosome-like organelle and mitochondria may provide new insights into the understanding of the complex interplay between the mitochondria and lysosome-mediated signalling routes during mammalian apoptosis. 相似文献