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981.
Anna Mara Scandroglio Gabriele Finco Marina Pieri Roberto Ascari Maria Grazia Calabrò Daiana Taddeo Francesca Isella Annalisa Franco Mario Musu Giovanni Landoni Ottavio Alfieri Alberto Zangrillo 《BMC anesthesiology》2015,15(1)
Background
The elderly undergo cardiac surgery more and more frequently, often present multiple comorbidities, assume chronic therapies, and present a unique physiology. Aim of our study was to analyze the experience of a referral cardiac surgery center with all types of cardiac surgery interventions performed in patients ≥80 years old over a six years’ period.Methods
A retrospective observational study performed in a university hospital. 260 patients were included in the study (3.5% of the patients undergoing cardiac surgery in the study period).Results
Mean age was 82 ± 1.8 years. Eighty-five percent of patients underwent elective surgery, 15% unplanned surgery and 4.2% redo surgery. Intervention for aortic valve pathology and coronary artery bypass grafting were performed in 51% and 46% of the patients, respectively. Interventions involving the mitral valve were the 26% of the total, those on the tricuspid valve were 13% and those on the ascending aortic arch the 9.6%. Postoperative low output syndrome was identified in 44 patients (17%). Mortality was 3.9% and most of the patients (91%) were discharged from hospital in good clinical conditions. Hospital mortality was lower in planned vs unplanned surgery: 3.8% vs 14% respectively. Chronic obstructive pulmonary disease (OR 9.106, CI 2.275 – 36.450) was the unique independent predictor of mortality.Conclusions
Clinicians should be aware that cardiac surgery can be safely performed at all ages, that risk stratification is mandatory and that hemodynamic treatment to avoid complications is expected.Electronic supplementary material
The online version of this article (doi:10.1186/1471-2253-15-15) contains supplementary material, which is available to authorized users. 相似文献982.
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987.
Pierpaolo Ceci Gisa Di Cecca Mattia Falconi Francesco Oteri Carlotta Zamparelli Emilia Chiancone 《Journal of biological inorganic chemistry》2011,16(6):869-880
DNA-binding proteins from starved cells (Dps) differ in the number and position of charged residues along the “ferritin-like”
pores that are used by iron to reach the ferroxidase center and the protein cavity. These differences are shown to affect
significantly the electrostatic potential at the pores, which determines the extent of cooperativity in the iron uptake kinetics
and thereby the mass distribution of the ferric hydroxide micelles inside the protein cavity. These conclusions are of biotechnological
value in the preparation of protein-enclosed nanomaterials and are expected to apply also to ferritins. They were reached
after characterization of the Dps from Listeria innocua, Helicobacter pylori, Thermosynechococcus elongatus, Escherichia coli, and Mycobacterium smegmatis. The characterization comprised the calculation of the electrostatic potential at the pores, determination of the iron uptake
kinetics in the presence of molecular oxygen or hydrogen peroxide, and analysis of the proteins by means of the sedimentation
velocity after iron incorporation. 相似文献
988.
Cassano M Dellavalle A Tedesco FS Quattrocelli M Crippa S Ronzoni F Salvade A Berardi E Torrente Y Cossu G Sampaolesi M 《Development (Cambridge, England)》2011,138(20):4523-4533
Mice deficient in α-sarcoglycan (Sgca-null mice) develop progressive muscular dystrophy and serve as a model for human limb girdle muscular dystrophy type 2D. Sgca-null mice suffer a more severe myopathy than that of mdx mice, the model for Duchenne muscular dystrophy. This is the opposite of what is observed in humans and the reason for this is unknown. In an attempt to understand the cellular basis of this severe muscular dystrophy, we isolated clonal populations of myogenic progenitor cells (MPCs), the resident postnatal muscle progenitors of dystrophic and wild-type mice. MPCs from Sgca-null mice generated much smaller clones than MPCs from wild-type or mdx dystrophic mice. Impaired proliferation of Sgca-null myogenic precursors was confirmed by single fiber analysis and this difference correlated with Sgca expression during MPC proliferation. In the absence of dystrophin and associated proteins, which are only expressed after differentiation, SGCA complexes with and stabilizes FGFR1. Deficiency of Sgca leads to an absence of FGFR1 expression at the membrane and impaired MPC proliferation in response to bFGF. The low proliferation rate of Sgca-null MPCs was rescued by transduction with Sgca-expressing lentiviral vectors. When transplanted into dystrophic muscle, Sgca-null MPCs exhibited reduced engraftment. The reduced proliferative ability of Sgca-null MPCs explains, at least in part, the severity of this muscular dystrophy and also why wild-type donor progenitor cells engraft efficiently and consequently ameliorate disease. 相似文献
989.
Manfredi P Renzi F Mally M Sauteur L Schmaler M Moes S Jenö P Cornelis GR 《Molecular microbiology》2011,81(4):1050-1060
Capnocytophaga canimorsus are commensal Gram-negative bacteria from dog's mouth that cause rare but dramatic septicaemia in humans. C. canimorsus have the unusual property to feed on cultured mammalian cells, including phagocytes, by harvesting the glycan moiety of cellular glycoproteins. To understand the mechanism behind this unusual property, the genome of strain Cc5 was sequenced and analysed. In addition, Cc5 bacteria were cultivated onto HEK 293 cells and the surface proteome was determined. The genome was found to encode many lipoproteins encoded within 13 polysaccharide utilization loci (PULs) typical of the Flavobacteria-Bacteroides group. PULs encode surface exposed feeding complexes resembling the archetypal starch utilization system (Sus). The products of at least nine PULs were detected among the surface proteome and eight of them represented more than half of the total peptides detected from the surface proteome. Systematic deletions of the 13 PULs revealed that half of these Sus-like complexes contributed to growth on animal cells. The complex encoded by PUL5, one of the most abundant ones, was involved in foraging glycans from glycoproteins. It was essential for growth on cells and contributed to survival in mice. It thus represents a fitness factor during infection. 相似文献
990.
Giovannini M Verduci E Radaelli G Lammardo A Minghetti D Cagnoli G Salvatici E Riva E 《Prostaglandins, leukotrienes, and essential fatty acids》2011,84(1-2):39-42
IntroductionThe aim of the present study was to examine whether hyperphenylalaninemic children on unrestricted diet (MHP) may exhibit a different LCPUFA profile from PKU or healthy children in plasma phospholipids.Patients and methodsForty-five MHP children (age 9–14 years) were age and sex matched with 45 PKU and 45 healthy children. Fatty acids were determined and expressed as % of total fatty acids.ResultsMHP children showed docosahexaenoic acid (DHA) levels higher than PKU children (mean difference, 0.2%; 95% confidence interval, 0.02%–0.38%), although difference was not significant after correction for multiple comparisons, and lower levels than healthy children (?0.8%; ?1.01% to ?0.59%). Concentration of n-3 PUFA was higher in MHP than PKU children (0.6%; 0.4% to 0.8%),ConclusionsThe results suggest that low DHA levels in plasma phospholipids not only are evident in PKU but also may occur in MHP children, who are on unrestricted diet, as compared to healthy children. 相似文献