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Objectives: Active ageing, considered from the perspective of participation in leisure activities, promotes life satisfaction and personal well-being. The aims of this work are to define and explain leisure activity profiles among institutionalized older adults, considering their sociodemographic characteristics and objective and subjective conditions in relation to their quality of life.

Methods: Two samples of institutionalized people aged 60 and over were analysed together: 234 older adults without dementia and 525 with dementia. Sociodemographic, economic, family and social network, and health and functioning variables were selected. Cluster analysis was applied to obtain activity profiles according to the leisure activities, and ordinal regression models were performed to analyse factors associated to activity level.

Results: The sample was clustered into three groups of people: active (27%), moderately active (35%) and inactive people (38%). In the final regression model (Nagelkerke pseudo R2 = 0.500), a higher level of activity was associated with better cognitive function (Pfeiffer scale), self-perceived health status and functional ability, as well as with a higher frequency of gathering with family and friends, and higher educational level.

Conclusion: The decline in physical and mental health, the loss of functional capabilities and the weakening of family and social ties represent a significant barrier to active ageing in a context of institutionalization.  相似文献   

84.

Background

Fewer bleeding complications and early ambulation make radial access a privileged route for cardiac catheterization. However, transradial (TR) approach is not always successful, requiring its conversion into femoral access.

Objectives

To evaluate the rate of conversion from radial into femoral access in cardiac catheterization and to identify its predictors.

Methods

Prospective dual-center registry, including 7632 consecutive patients undergoing catheterization via the radial access between Jan/2009 and Oct/2012. We evaluated the incidence of conversion into femoral access and its predictors by logistic regression analysis.

Results

The patients’ mean age was 66 ± 11 years, and 32% were women. A total of 2969 procedures (38.4%) were percutaneous coronary interventions (PCI), and the most used first intention arterial access was the right radial artery (97.6%). Radial access failure rate was 5.8%. Independent predictors of conversion from radial into femoral access were the use of short introducer sheaths (OR 3.047, CI: 2.380-3.902; p < 0.001), PCI (OR 1.729, CI: 1.375-2.173; p < 0.001), female sex (OR 1.569, CI: 1.234-1.996; p < 0.001), multivessel disease (OR 1.457, CI: 1.167-1.819; p = 0.001), body surface area (BSA) ≤ 1.938 (OR 1.448, CI: 1.120-1.871; p = 0.005) and age > 66 years (OR 1.354, CI: 1.088-1.684; p = 0.007).

Conclusion

Transradial approach for cardiac catheterization has a high success rate and the need for its conversion into femoral access in this cohort was low. Female sex, older age, smaller BSA, the use of short introducer sheaths, multivessel disease and PCI were independent predictors of conversion into femoral access.  相似文献   
85.
Fresh adipose-derived cells have been shown to be effective in the treatment of acute myocardial infarction (MI), but their role in the chronic setting is unknown. We sought to determine the long-term effect of the adipose derived-stromal vascular fraction (SVF) cell transplantation in a rat model of chronic MI. MI was induced in 82 rats by permanent coronary artery ligation and 5 weeks later rats were allocated to receive an intramyocardial injection of 10(7) GFP-expressing fresh SVF cells or culture media as control. Heart function and tissue metabolism were determined by echocardiography and (18)F-FDG-microPET, respectively, and histological studies were performed for up to 3 months after transplantation. SVF induced a statistically significant long-lasting (3 months) improvement in cardiac function and tissue metabolism that was associated with increased revascularization and positive heart remodeling, with a significantly smaller infarct size, thicker infarct wall, lower scar fibrosis, and lower cardiac hypertrophy. Importantly, injected cells engrafted and were detected in the treated hearts for at least 3 months, directly contributing to the vasculature and myofibroblasts and at negligible levels to cardiomyocytes. Furthermore, SVF release of angiogenic (VEGF and HGF) and proinflammatory (MCP-1) cytokines, as well as TIMP1 and TIMP4, was demonstrated in vitro and in vivo, strongly suggesting that they have a trophic effect. These results show the potential of SVF to contribute to the regeneration of ischemic tissue and to provide a long-term functional benefit in a rat model of chronic MI, by both direct and indirect mechanisms.  相似文献   
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88.

Background

Implant restorations have become a high predictable treatment option. Several caracteristics such as surgical technique and implant design can influence the treatment outcomes. The aim of the present study was to evaluate the influence of implant macro-design on primary stability measured with resonance frequency analysis (RFA) and insertion torque (IT).

Material and Methods

A total of 47 implants divided in two groups: Test group (TI): 22 Tapered MIS® Seven implants; Control group (CI): 25 cylindrical Astra® Osseospeed implants. All implants were inserted following the manufacturers’ standard protocols. Implant primary stability was measured at the moment of implant placement by registering insertion torque values (ITv) and ISQ values by means of Osstell™ Mentor (ISQv) (Integration Diagnostic Ltd., Goteborg, Sweden).

Results

In the mandible, mean ISQv for tapered implants (TI) was 71.67±5.16 and for cylindrical implants (CI) 57.15±4.83 (p=0.01). Mean insertion torque was 46.67±6.85 Ncm for TI and 35.77±6.72 Ncm for CI (p=0.01). In the maxilla, mean ISQ was 67.2±4.42 for tapered implants and 49.17±15.30 for cylindrical implants (p=0.01). Mean insertion torque for TI was 41.5±6.26 Ncm and for CI 39.17±6.34 Ncm (p>0.05). For tapered implants, no correlation could be found between implant diameter and primary stability. But for cylindrical implants there was a statistically significant correlation between implant diameter and primary stability: ITv (p=0.03); ISQv (p=0.04).

Conclusions

Within the limits of the present study, tapered shaped implants achieve higher primary stability measured through ISQ and insertion torque values. Moreover, for cylindrical implants positive correlation has been established between implant diameter and primary stability. Key words:Primary stability, tapered, cylindrical, conical, implant macro-design.  相似文献   
89.
In bacteria, the FtsK/Xer/dif (chromosome dimer resolution site) system is essential for faithful vertical genetic transmission, ensuring the resolution of chromosome dimers during their segregation to daughter cells. This system is also targeted by mobile genetic elements that integrate into chromosomal dif sites. A central question is thus how Xer/dif recombination is tuned to both act in chromosome segregation and stably maintain mobile elements. To explore this question, we focused on pathogenic Neisseria species harboring a genomic island in their dif sites. We show that the FtsK DNA translocase acts differentially at the recombination sites flanking the genomic island. It stops at one Xer/dif complex, activating recombination, but it does not stop on the other site, thus dismantling it. FtsK translocation thus permits cis discrimination between an endogenous and an imported Xer/dif recombination complex.In all organisms, the processing of chromosome ends or termini relies on specific activities for replication and segregation. In eukaryotes, telomeres are often targeted by mobile genetic elements, which may even substitute for telomeric functions (1). Circular chromosomes found in prokaryotes have no telomeres but harbor chromosome dimer resolution sites, called dif sites, on which dedicated Xer recombinases (XerC and XerD in most cases) act (2, 3). Besides their role in chromosome maintenance, dif sites are targeted by numerous mobile genetic elements, referred to as integrating mobile element exploiting Xer (IMEX) (4). How IMEXs integrate into dif without inactivating its cellular function and how they are stably maintained in their integrated state has remained unclear despite study over the past decade (47). Here we answer these questions by studying the gonococcal genomic island (GGI), an IMEX stably integrated into the dif site of pathogenic Neisseria species that encodes crucial functions for gene exchange and virulence (8, 9).In Escherichia coli, chromosome dimers form by homologous recombination during replication and are resolved by site-specific recombination between sister dif sites catalyzed by the XerC and XerD recombinases (Fig. 1) (3). The 28-bp dif site carries binding sites for each recombinase, separated by a 6-bp central region at the border of which strand exchanges are catalyzed. After assembly of the recombination complex (synapse), one pair of strands is exchanged by the XerD monomers, leading to a branched DNA intermediate (Holliday junction, HJ) subsequently resolved by XerC. Dimer resolution is integrated into the general processing of the terminal region of the chromosome (ter region) during cell division (10). FtsK, a DNA translocase associated with the division apparatus, segregates this region at the onset of cell division (10, 11). The translocation motor, FtsKαβ, is located in the C terminal of FtsK (12). Translocation is oriented toward the dif site located at the center of the ter region via a direct interaction between the extreme C-terminal subdomain of FtsK, FtsKγ, and the KOPS DNA motifs (13). Upon reaching the XerCD/dif complex, FtsK stops translocating and activates recombination via direct interaction with XerD (14, 15) (Fig. 1). The mechanisms of translocation arrest and of recombination activation are poorly understood but they both involve FtsKγ. However, these activities appear to be distinct from each other because FtsKγ can activate recombination in vivo and in vitro when isolated from the FtsKαβ motor or fused to XerC or XerD (16).Open in a separate windowFig. 1.The XerCD/dif recombination. (A) Chromosome dimer formation by homologous recombination (HR) during replication and resolution by site-specific recombination between the two dif sites. The dif site is represented as green and purple boxes for the XerC-binding and the XerD-binding sites, respectively. ori (black circle), some KOPS motifs (arrows), and the ter domain (thick line) are represented. The mechanism of XerCD/dif recombination is represented in the box. XerC (green circles) and XerD (purple circles) bind two distant dif sites to create a synapse. Hexamers of the FtsK C-terminal domain [FtsKC: FtsKαβ: (diamonds) + FtsKγ: (triangle) contacting XerD] translocate toward dif and contact XerD. This activates XerD (Y indicates the active recombinases), which catalyzes the first-strand exchange. This process leads to the formation of an HJ intermediate within which XerC is active and catalyzes the second-strand exchange (3). (B) Integration and excision of the GGI (dotted line) by XerCD catalysis. KOPS, difNg, and difGGI sites are represented as in A. An alignment of difNg, difGGI and consensus dif sequence (27, 28) is shown on the left. Substituted positions in difGGI are represented as lowercase characters and highlighted by stars.In numerous bacteria, the XerCD/dif system is hijacked by IMEXs, which integrate their host genome into dif sites by using XerCD-mediated catalysis (4). In all of the reported cases, integration of IMEXs recreates a bona fide dif site, thereby not interfering with chromosome dimer resolution, which would lead to their counter-selection. The best-described examples are Vibrio cholerae IMEXs, which carry crucial virulence determinants (57, 17). These IMEXs have developed different strategies to integrate and to remain stably integrated, although the mechanisms ensuring their stable maintenance are not fully understood. Neisseria species contain an unusually long IMEX called the gonococcal genomic island (GGI) (8). In Neisseria gonorrheae, the GGI is 57 kb long and encodes a type IV secretion system that exports the chromosomal DNA of its host, rendering it available to neighboring cells for gene exchange by genetic transformation (8, 18). The GGI carries a dif site, difGGI, consisting of a XerC-binding site, a central region homologous to the Neisseria dif site, difNg, and a divergent XerD-binding site (Fig. 1B). Comparison of N. gonorrheae strains harboring or lacking the GGI, together with functional data, indicates that the GGI integrates by XerCD-dependent recombination (9). The nonreplicative excised circular form of the GGI can be detected and the GGI can also be lost, showing that excision occurs, although at low frequencies (9). Although the GGI was identified over a decade ago, it has remained unclear how DNA flanked by two Xer recombination sites is stably maintained at a chromosomal locus processed by FtsK during each cell cycle. In this study, we have combined in vitro and in vivo approaches to show that difGGI is indeed an active Xer recombination site at which the Neisseria Xer recombinases catalyze recombination when activated by FtsKγ. However, we find that recombination between difNg and difGGI is inhibited by translocating FtsK. Inhibition is a result of the absence of translocation arrest at XerCDNg/difGGI complexes that most likely precludes recombination activation, an absence that causes the complex to dismantle. We conclude that, depending on the sequence of the recombination site, Xer recombination complexes have the intrinsic capacity to be activated or inhibited by FtsK.  相似文献   
90.
The left atrial appendage aneurysm is a rare condition that frequently manifests itself by heart arrhythmias or thromboembolism. We report the case of a patient with left atrial appendage aneurysm, diagnosed by echocardiography and submitted to surgical resection.  相似文献   
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