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991.
Chavan SS Huerta PT Robbiati S Valdes-Ferrer S Ochani M Dancho M Frankfurt M Volpe BT Tracey KJ Diamond B 《Molecular medicine (Cambridge, Mass.)》2012,18(9):930-937
Severe sepsis, a syndrome that complicates infection and injury, affects 750,000 annually in the United States. The acute mortality rate is approximately 30%, but, strikingly, sepsis survivors have a significant disability burden: up to 25% of survivors are cognitively and physically impaired. To investigate the mechanisms underlying persistent cognitive impairment in sepsis survivors, here we developed a murine model of severe sepsis survivors following cecal ligation and puncture (CLP) to study cognitive impairments. We observed that serum levels of high mobility group box 1 (HMGB1), a critical mediator of acute sepsis pathophysiology, are increased in sepsis survivors. Significantly, these levels remain elevated for at least 4 wks after CLP. Sepsis survivors develop significant, persistent impairments in learning and memory, and anatomic changes in the hippocampus associated with a loss of synaptic plasticity. Administration of neutralizing anti-HMGB1 antibody to survivors, beginning 1 wk after onset of peritonitis, significantly improved memory impairments and brain pathology. Administration of recombinant HMGB1 to na?ve mice recapitulated the memory impairments. Together, these findings indicate that elevated HMGB1 levels mediate cognitive decline in sepsis survivors, and suggest that it may be possible to prevent or reverse cognitive impairments in sepsis survivors by administration of anti-HMGB1 antibodies. 相似文献
992.
Julio Álvarez Andrés Perez Sergio Marqués Javier Bezos Anna Grau Maria Luisa de la Cruz Beatriz Romero Jose Luis Saez Maria del Rosario Esquivel Maria del Carmen Martínez Olga Mínguez Lucía de Juan Lucas Domínguez 《BMC veterinary research》2014,10(1):1-10
Background
Despite great effort and investment incurred over decades to control bovine tuberculosis (bTB), it is still one of the most important zoonotic diseases in many areas of the world. Test-and-slaughter strategies, the basis of most bTB eradication programs carried out worldwide, have demonstrated its usefulness in the control of the disease. However, in certain countries, eradication has not been achieved due in part to limitations of currently available diagnostic tests. In this study, results of in-vivo and post-mortem diagnostic tests performed on 3,614 animals from 152 bTB-infected cattle herds (beef, dairy, and bullfighting) detected in 2007–2010 in the region of Castilla y León, Spain, were analyzed to identify factors associated with positive bacteriological results in cattle that were non-reactors to the single intradermal tuberculin test, to the interferon-gamma (IFN-γ) assay, or to both tests applied in parallel (Test negative/Culture + animals, T-/C+). The association of individual factors (age, productive type, and number of herd-tests performed since the disclosure of the outbreak) with the bacteriology outcome (positive/negative) was analyzed using a mixed multivariate logistic regression model.Results
The proportion of non-reactors with a positive post-mortem result ranged from 24.3% in the case of the SIT test to 12.9% (IFN-γ with 0.05 threshold) and 11.9% (95% CI 9.9-11.4%) using both tests in parallel. Older (>4.5 years) and bullfighting cattle were associated with increased odds of confirmed bTB infection by bacteriology, whereas dairy cattle showed a significantly lower risk. Ancillary use of IFN-γ assay reduced the proportion of T-/C + animals in high risk groups.Conclusions
These results demonstrate the likelihood of positive bacteriological results in non-reactor cattle is influenced by individual epidemiological factors of tested animals. Increased surveillance on non-reactors with an increased probability of being false negative could be helpful to avoid bTB persistence, particularly in chronically infected herds. These findings may aid in the development of effective strategies for eradication of bTB in Spain. 相似文献993.
994.
Daniel Guillén Sergio Sánchez Romina Rodríguez-Sanoja 《Applied microbiology and biotechnology》2010,85(5):1241-1249
Insoluble polysaccharides can be degraded by a set of hydrolytic enzymes formed by catalytic modules appended to one or more
non-catalytic carbohydrate-binding modules (CBM). The most recognized function of these auxiliary domains is to bind polysaccharides,
bringing the biocatalyst into close and prolonged vicinity with its substrate, allowing carbohydrate hydrolysis. Examples
of insoluble polysaccharides recognized by these enzymes include cellulose, chitin, β-glucans, starch, glycogen, inulin, pullulan,
and xylan. Based on their amino acid similarity, CBMs are grouped into 55 families that show notable variation in substrate
specificity; as a result, their biological functions are miscellaneous. Carbohydrate or polysaccharide recognition by CBMs
is an important event for processes related to metabolism, pathogen defense, polysaccharide biosynthesis, virulence, plant
development, etc. Understanding of the CBMs properties and mechanisms in ligand binding is of vital significance for the development
of new carbohydrate-recognition technologies and provide the basis for fine manipulation of the carbohydrate–CBM interactions. 相似文献
995.
Sergio Padilla-López María Jiménez-Hidalgo Alejandro Martín-Montalvo Catherine F. Clarke Plácido Navas Carlos Santos-Ocaña 《生物化学与生物物理学报:生物膜》2009,1788(6):1238-1248
Coenzyme Q is an isoprenylated benzoquinone lipid that functions in respiratory electron transport and as a lipid antioxidant. Dietary supplementation with Q is increasingly used as a therapeutic for treatment of mitochondrial and neurodegenerative diseases, yet little is known regarding the mechanism of its uptake. As opposed to other yeast backgrounds, EG103 strains are unable to import exogenous Q6 to the mitochondria. Furthermore, the distribution of exogenous Q6 among endomembranes suggests an impairment of the membrane traffic at the level of the endocytic pathway. This fact was confirmed after the detection of defects in the incorporation of FM4-64 marker and CPY delivery to the vacuole. A similar effect was demonstrated in double mutant strains in Q6 synthesis and several steps of endocytic process; those cells are unable to uptake exogenous Q6 to the mitochondria and restore the growth on non-fermentable carbon sources. Additional data about the positive effect of peptone presence for exogenous Q6 uptake support the hypothesis that Q6 is transported to mitochondria through an endocytic-based system. 相似文献
996.
Relationship between molecular and enological features of Patagonian wine yeasts: relevance in selection protocols 总被引:4,自引:0,他引:4
Christian A. Lopes María E. Rodríguez Amparo Querol Sergio Bramardi Adriana C. Caballero 《World journal of microbiology & biotechnology》2006,22(8):827-833
Summary In this paper, a study of the relationship between genetic patterns, obtained by the combination of mtDNA-RFLP and PCR-amplified inter-δ sequence DNA polymorphism analysis, and relevant enological phenotypic data (fermentative power, specific productivity, volatile and total acidity) was carried out on Argentinean Saccharomyces cerevisiae isolates from north Patagonia. The use of a powerful statistical tool, Generalized Procrustes analysis, allowed us to weigh the relationship for each isolate in particular, denoting a good enough degree of agreement between molecular and physiological data for most of the population analysed. The inclusion of a physiological feature, as the killer sensitivity biotype, within identification methods resulted in a higher degree of discrimination among isolates and in better correlation between both characterizations. The combined use of methods based on molecular polymorphisms and killer biotype could be applied so as not to miss any isolate with differential enological properties in selection protocols. 相似文献
997.
998.
999.
Han SJ Vaccari S Nedachi T Andersen CB Kovacina KS Roth RA Conti M 《The EMBO journal》2006,25(24):5716-5725
cGMP-inhibited cAMP phosphodiesterase 3A (PDE3A) is expressed in mouse oocytes, and its function is indispensable for meiotic maturation as demonstrated by genetic ablation. Moreover, PDE3 activity is required for insulin/insulin-like growth factor-1 stimulation of Xenopus oocyte meiotic resumption. Here, we investigated the cAMP-dependent protein kinase B (PKB)/Akt regulation of PDE3A and its impact on oocyte maturation. Cell-free incubation of recombinant mouse PDE3A with PKB/Akt or cAMP-dependent protein kinase A catalytic subunits leads to phosphorylation of the PDE3A protein. Coexpression of PDE3A with constitutively activated PKB/Akt (Myr-Akt) increases PDE activity as well as its phosphorylation state. Injection of pde3a mRNA potentiates insulin-dependent maturation of Xenopus oocytes and rescues the phenotype of pde3(-/-) mouse oocytes. This effect is greatly decreased by mutation of any of the PDE3A serines 290-292 to alanine in both Xenopus and mouse. Microinjection of myr-Akt in mouse oocytes causes in vitro meiotic maturation and this effect requires PDE3A. Collectively, these data indicate that activation of PDE3A by PKB/Akt-mediated phosphorylation plays a role in the control of PDE3A activity in mammalian oocytes. 相似文献
1000.
Covarrubias SA de-Bashan LE Moreno M Bashan Y 《Applied microbiology and biotechnology》2012,93(6):2669-2680
When the freshwater microalga Chlorella sorokiniana and the plant growth-promoting bacterium Azospirillum brasilense were deployed as free suspensions in unsterile, municipal wastewater for tertiary wastewater treatment, their population
was significantly lower compared with their populations in sterile wastewater. At the same time, the numbers of natural microfauna
and wastewater bacteria increased. Immobilization of C. sorokiniana and A. brasilense in small (2–4 mm in diameter), polymer Ca-alginate beads significantly enhanced their populations when these beads were suspended
in normal wastewater. All microbial populations within and on the surface of the beads were evaluated by quantitative fluorescence
in situ hybridization combined with scanning electron microscopy and direct measurements. Submerging immobilizing beads in
wastewater created the following sequence of events: (a) a biofilm composed of wastewater bacteria and A. brasilense was created on the surface of the beads, (b) the bead inhibited penetration of outside organisms into the beads, (c) the
bead inhibited liberation of the immobilized microorganisms into the wastewater, and (d) permitted an uninterrupted reduction
of ammonium and phosphorus from the wastewater. This study demonstrated that wastewater microbial populations are responsible
for decreasing populations of biological agents used for wastewater treatment and immobilization in alginate beads provided
a protective environment for these agents to carry out uninterrupted tertiary wastewater treatment. 相似文献