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121.
Olga P. Nyssen Angeles Perez‐Aisa Luis Rodrigo Manuel Castro Pilar Mata Romero Juan Ortuo Jesus Barrio Jose Maria Huguet Ines Modollel Noelia Alcaide Alfredo Lucendo Xavier Calvet Monica Perona Barbara Gomez Blas Jose Gomez Rodriguez Pilar Varela Manuel Jimenez‐Moreno Manuel Dominguez‐Cajal Liliana Pozzati Diego Burgos Luis Bujanda Jenifer Hinojosa Javier Molina‐Infante Tommaso Di Maira Luis Ferrer Luis Fernndez‐Salazar Ariadna Figuerola Llucia Tito Cristobal de la Coba Judith Gomez‐Camarero Nuria Fernandez Maria Caldas Ana Garre Elena Resina Ignasi Puig Colm OMorain Francis Megraud Javier P. Gisbert 《Helicobacter》2020,25(5)
122.
Vorobjeva L Leverrier P Zinchenko A Boyaval P Khodjaev E Varioukhina S Ponomareva G Gordeeva E Jan G 《Antonie van Leeuwenhoek》2004,85(1):53-62
Propionibacterium freudenreichii subsp. shermanii is known to prevent mutations caused by various agents such as N-methyl-N'-nitro-N-nitrosoguanidine, 9-aminoacridine, 4-nitro-quinoline-1-oxide and by UV radiation in both prokaryotic and eukaryotic cells. It was also shown to prevent or repair damage caused by H(2)O(2) or UV radiation in Salmonella typhimurium and Escherichia coli, a characteristic previously designated as reactivative effect. In order to characterise this effect at the molecular level, we have purified the active component from a P. freudenreichii cell-free extract using a combination of ammonium sulfate precipitation, anion-exchange and size-exclusion chromatography. The isolated 35 kDa protein was then identified using both N-terminal and internal peptide sequencing as a cysteine synthase. The latter was localised in the P. freudenreichii proteomic map. It is constitutively expressed but also clearly induced during adaptation to detergent and heat, but not acid, stresses. The biological meaning of cysteine synthase in the context of adaptation to oxidative and non-oxidative stresses is discussed. 相似文献
123.
The global analysis of metabolism by liquid chromatography coupled to mass spectrometry is often hampered by a large amount of biological and technical variability. Here, we introduce an experimental and analytical strategy that can produce robust metabolome profiles in the face of this challenge. By applying a new computational approach based on concordance analysis to an extremely large number of analytical replicates, we are able to show that the overexpression of an antisense non-coding RNA targeting glutamine synthetase I results in a major reorganization of the metabolism of Streptomyces coelicolor, the model species of antibiotic-producing bacteria. We identified 97 metabolites with statistically significant reproducible dynamic behavior across the time series. The observed metabolic changes are very rapid, specific and widespread across metabolism, but focus on the nitrogen assimilation pathways. Our results demonstrate the power of highly replicated experimental designs for the robust characterization of metabolite dynamics. The identified global rearrangement of metabolism suggests the usefulness of RNA interference as an efficient strategy to manipulate the physiology of bacteria with wider biotechnological applicability in microorganisms. 相似文献
124.
Stefania Raimondo Ornella Urzì Serena Meraviglia Marta Di Simone Anna Maria Corsale Nima Rabienezhad Ganji Antonio Palumbo Piccionello Giulia Polito Elena Lo Presti Francesco Dieli Alice Conigliaro Riccardo Alessandro 《Journal of cellular and molecular medicine》2022,26(15):4195
Chronic inflammation is associated with the occurrence of several diseases. However, the side effects of anti‐inflammatory drugs prompt the identification of new therapeutic strategies. Plant‐derived extracellular vesicles (PDEVs) are gaining increasing interest in the scientific community for their biological properties. We isolated PDEVs from the juice of Citrus limon L. (LEVs) and characterized their flavonoid, limonoid and lipid contents through reversed‐phase high‐performance liquid chromatography coupled to electrospray ionization quadrupole time‐of‐flight mass spectrometry (RP‐HPLC–ESI‐Q‐TOF‐MS). To investigate whether LEVs have a protective role on the inflammatory process, murine and primary human macrophages were pre‐treated with LEVs for 24 h and then were stimulated with lipopolysaccharide (LPS). We found that pre‐treatment with LEVs decreased gene and protein expression of pro‐inflammatory cytokines, such as IL‐6, IL1‐β and TNF‐α, and reduced the nuclear translocation and phosphorylation of NF‐κB in LPS‐stimulated murine macrophages. The inhibition of NF‐κB activation was associated with the reduction in ERK1‐2 phosphorylation. Furthermore, the ability of LEVs to decrease pro‐inflammatory cytokines and increase anti‐inflammatory molecules was confirmed ex vivo in human primary T lymphocytes. In conclusion, we demonstrated that LEVs exert anti‐inflammatory effects both in vitro and ex vivo by inhibiting the ERK1‐2/NF‐κB signalling pathway. 相似文献
125.
Gareth Betts Hazel Poyntz Elena Stylianou Arturo Reyes-Sandoval Matthew Cottingham Adrian Hill Helen McShane 《PloS one》2012,7(12)
The Bacillus Calmette - Guerin (BCG) vaccine provides a critical but limited defense against Mycobacterium tuberculosis (M.tb). More than 60 years after the widespread introduction of BCG, there is an urgent need for a better vaccine. A large body of pre-clinical research continues to support ongoing clinical trials to assess whether viral vectors expressing M.tb antigens that are shared by BCG and M.tb, can be used alongside BCG to enhance protection. A major focus involves using multiple unique viral vectors to limit anti-vector immunity and thereby enhance responses to the insert antigen delivered. The successful introduction of viral vector vaccines to target M.tb and other pathogens will be reliant on reducing the costs when using multiple vectors and inhibiting the development of unwanted anti-vector responses that interfere with the response to insert antigen. This study examines methods to reduce the logistical costs of vaccination by mixing different viral vectors that share the same insert antigen in one vaccine; and whether combining different viral vectors reduces anti-vector immunity to improve immunogenicity to the insert antigen. Here we show that a homologous prime-boost regimen with a mixture of MVA (Modified Vaccinia virus Ankara) and Ad5 (human adenovirus type 5) vectors both expressing Ag85A in a single vaccine preparation is able to reduce anti-vector immunity, compared with a homologous prime-boost regimen with either vector alone. However, the level of immunogenicity induced by the homologous mixture remained comparable to that induced with single viral vectors and was less immunogenic than a heterologous Ad5 prime-MVA-boost regimen. These findings advance the understanding of how anti-vector immunity maybe reduced in viral vector vaccination regimens. Furthermore, an insight is provided to the impact on vaccine immunogenicity from altering vaccination methods to reduce the logistical demands of using separate vaccine preparations in the field. 相似文献
126.
María Elena González-Benito Carolina Kremer Miguel A. Ibáñez Carmen Martín 《Plant Cell, Tissue and Organ Culture》2016,127(2):359-368
The effect of antioxidants applied in one step of a cryopreservation protocol by encapsulation–dehydration on recovery and genetic stability of mint shoot tips has been studied. Glutathione (0.16 or 0.24 mM), ascorbic acid (0.28 or 0.43 mM) and α-tocopherol (vitamin E) were added to the preculture medium (0.3 M sucrose). DNA was extracted from three different types of samples: leaves from shoots, callus at the base of shoots and callus. RAPD and AFLP markers were used to assess the genetic stability. The use of antioxidants did not improve recovery after cryopreservation. One of the genotypes, ‘MEN 198’, showed higher percentage of stable samples than the other one, ‘MEN 186’ (56 vs. 37?%; considering all treatments and types of explant). The use of vitamin E improved the percentage of stable samples with respect to control treatment (no antioxidant) in ‘MEN 186’. No differences in the percentages of stable samples were observed among cryopreserved and non-cryopreserved (treated similarly without immersion in liquid nitrogen) plant material. Recovered shoots of both genotypes showed higher stability (76–80?% stable samples) than callus samples (14–22?%). 相似文献
127.
128.
Pier Sandro Cocconcelli Elena Ferrari Filippo Rossi Vittorio Bottazzi 《FEMS microbiology letters》1992,94(3):203-207
To apply recombinant DNA techniques to the genetic manipulation of cellulolytic ruminal bacteria, a plasmid vector transformation system must be available. The objective of this work was to develop a system for plasmid transformation of Ruminococcus albus. Using high voltage electrotransformation, pSC22 and pCK17 plasmid vectors, derived from lactic acid bacteria plasmids and replicating via single-stranded DNA intermediate, were successfully introduced into three freshly isolated R. albus strains and into R. albus type strain ATCC 27210. The optimization of the electrotransformation condition raised the electroporation efficiency up to 3 x 10(5) transformants per microgram of pSC22 plasmid. 相似文献
129.
130.
Elena Roura Ma Pilar Almajano Ma Lourdes Mata Bilbao Cristina Andrés-Lacueva Ramon Estruch 《Free radical research》2013,47(8):943-949
Associations between cocoa consumption in humans, excreted metabolites and total antioxidant capacity (TAC) have been scarcely investigated. The aims of the study were to investigate the epicatechin (( ? )-Ec) metabolites excreted in urine samples after an intake of 40 g of cocoa powder along with the TAC of these urine samples and the relation between both the analyses. Each of the 21 volunteers received two interventions, one with a polyphenol-rich food (PRF) and one with a polyphenol-free food (PFF) in a randomized cross-over study. Urine samples were taken before and during 24 h at 0–6, 6–12 and 12–24 h periods after test intake. The excreted ( ? )-Ec metabolites and the TAC were determined in urine samples by LC-MS/MS and TEAC assay, respectively. The maximum excretion of ( ? )-Ec metabolites and the maximum TAC value were observed in urine samples excreted between 6 and 12 h after PRF consumption. Significance of TAC increase was found in urine samples excreted during 0–6 and 6–12 h (66.6 and 72.67%, respectively, with respect to the 0 h). 相似文献