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251.
Laura M. Pérez Marco Inzitari Terence J. Quinn Joan Montaner Ricard Gavaldà Esther Duarte Laura Coll-Planas Mercè Cerdà Sebastià Santaeugenia Conxita Closa Miquel Gallofré 《PloS one》2016,11(11)
BackgroundStroke is a major cause of disability in older adults, but the evidence around post-acute treatment is limited and heterogeneous. We aimed to identify profiles of older adult stroke survivors admitted to intermediate care geriatric rehabilitation units.MethodsWe performed a cohort study, enrolling stroke survivors aged 65 years or older, admitted to 9 intermediate care units in Catalonia-Spain. To identify potential profiles, we included age, caregiver presence, comorbidity, pre-stroke and post-stroke disability, cognitive impairment and stroke severity in a cluster analysis. We also proposed a practical decision tree for patient’s classification in clinical practice. We analyzed differences between profiles in functional improvement (Barthel index), relative functional gain (Montebello index), length of hospital stay (LOS), rehabilitation efficiency (functional improvement by LOS), and new institutionalization using multivariable regression models (for continuous and dichotomous outcomes).ResultsAmong 384 patients (79.1±7.9 years, 50.8% women), we identified 3 complexity profiles: a) Lower Complexity with Caregiver (LCC), b) Moderate Complexity without Caregiver (MCN), and c) Higher Complexity with Caregiver (HCC). The decision tree showed high agreement with cluster analysis (96.6%). Using either linear (continuous outcomes) or logistic regression, both LCC and MCN, compared to HCC, showed statistically significant higher chances of functional improvement (OR = 4.68, 95%CI = 2.54–8.63 and OR = 3.0, 95%CI = 1.52–5.87, respectively, for Barthel index improvement ≥20), relative functional gain (OR = 4.41, 95%CI = 1.81–10.75 and OR = 3.45, 95%CI = 1.31–9.04, respectively, for top Vs lower tertiles), and rehabilitation efficiency (OR = 7.88, 95%CI = 3.65–17.03 and OR = 3.87, 95%CI = 1.69–8.89, respectively, for top Vs lower tertiles). In relation to LOS, MCN cluster had lower chance of shorter LOS than LCC (OR = 0.41, 95%CI = 0.23–0.75) and HCC (OR = 0.37, 95%CI = 0.19–0.73), for LOS lower Vs higher tertiles.ConclusionOur data suggest that post-stroke rehabilitation profiles could be identified using routine assessment tools and showed differential recovery. If confirmed, these findings might help to develop tailored interventions to optimize recovery of older stroke patients. 相似文献
252.
Monoclonal antibodies to adult chicken myosin light chains were generated and used to quantitate the types of myosin light-chain (MLC) isoforms expressed during development of the pectoralis major (PM), anterior latissimus dorsi (ALD), and medial adductor (MA) muscles of the chicken. These are muscles which, in the adult, are composed predominantly of fast, slow, and a mixture of fiber types, respectively. Three distinct phases of MLC expression characterized the development of the PM and MA muscles. The first identifiable pase occurred during the period of 5-7 d of incubation in ovo. Extracts of muscles from the pectoral region (which included the presumptive PM muscle) contained only fast MLC isoforms. This period of exclusive fast light-chain synthesis was followed by a phase (8- 12 d of incubation in ovo) in which coexpression of both fast and slow MLC isoforms was apparent in both PM and MA muscles. During the period, the composition of both fast and slow MLC isoforms in the PM and MA muscles was identical. Beginning at day 12 in ovo, the ALD was also subjected to immunochemical analyses. The proportion of fast and slow MLCs in this muscle at day 12 was similar to that present in the other muscles studied. The third development phase of MLC expression began at approximately 12 d of incubation in ovo and encompassed the transition in MLC composition to the isoform patterns incubation in ovo and encompassed the transition in MLC composition to the isoform patterns typical of adult muscle. During this period, the relative proportion of slow MLC rose in both the MA and ALD and fell in the PM. By day 16, the third fast light chain, LC(3f), was apparent in extracts of both the PM and MA. These results show that there is a developmental progression in the expression of MLC in the two avian muscles studied from day 5 in ovo; first, only fast MLCs are accumulated, then both fast and slow MLC isoforms are expressed. Only during the latter third of development in ovo is the final MLC isoform pattern characteristic of a particular muscle type expressed. 相似文献
253.
The active substance inducing competence in non-competent cells ofDiplococcus pneumoniae was isolated by ammonium sulphate precipitation from the sterile filtrate of a culture 40–60 min after the peak of competence
had passed. After being dialyzed and dried from the frozen state the substance was further purified by chromatography on Sephadex
G100 or DEAE cellulose column. In all cases the fractions containing the competence inducing activity contained also the transforming
DNA-inactivating activity. A hyperchromic increase of optical density was found on incubating the active substance with various
DNAs and RNAs as substrates. The hyperchromic increment is different from that of pancreatic endo-nuclease I and phosphodiesterase. 相似文献
254.
255.
To test the hygienic functional hypothesis of allogrooming in the white-crowned mangabey (Cercocebus torquatus lunulatus), we analyzed the distribution of such behavior over the body surface in the individuals of two captive groups of this species (N = 9 and N = 8). To sample the data, we used focal animal sampling and continuous recording. Before analyzing the data, we measured a representative subject in order to calculate the body surface area occupied by each site, defined accessibility rigorously (distinguishing among three categories of sites: easy to reach, difficult to reach, and inaccessible), and tested empirically the classification proposed. To determine whether allogrooming was likely to concentrate on the body sites with accessibility problems, we ran three successive analyses, each of with was increasingly specific: grouping types of sites, analyzing each site separately, and analyzing each subject's reception profile. The results obtained show that in both groups inaccessible sites received more allogrooming than predicted by their actual surface area; sites that were difficult to reach received an amount of allogrooming proportional to the body surface area they occupied, and those easy to reach received less allogrooming than expected. This complementarity between the distribution of auto- and allogrooming is consistent with the hygienic functional hypothesis of allogrooming. However, not all inaccessible sides nor those difficult-to-reach were allogroomed equally: Allogrooming concentrated primarily on dorsal and caudal regions, whose care is incompatible with a ventral/ventral orientation between groomer and groomee. The strong distributional selectivity of allogrooming and the interindividual variability in preferred allogrooming sites suggest that the hygienic functional hypothesis cannot fully account for all the aspects of the corporal distribution of such behavior. Thus, in support of the multifunctional nature of allogrooming, we conclude that there must be more than cleaning involved in Cercocebus torquatus lunulatus' allogrooming. 相似文献
256.
Shelf Life Degradation of Bulk Heterojunction Solar Cells: Intrinsic Evolution of Charge Transfer Complex
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Antonio Guerrero Hamed Heidari Teresa S. Ripolles Martin Pfannmöller Sara Bals Louis‐Dominique Kauffmann Juan Bisquert Germà Garcia‐Belmonte 《Liver Transplantation》2015,5(7)
Achievement of long‐term stability of organic photovoltaics is currently one of the major topics for this technology to reach maturity. Most of the techniques used to reveal degradation pathways are destructive and/or do not allow for real‐time measurements in operating devices. Here, three different, nondestructive techniques able to provide real‐time information, namely, film absorbance, capacitance–voltage (C–V), and impedance spectroscopy (IS), are combined over a period of 1 year using non‐accelerated intrinsic degradation conditions. It is discerned between chemical modifications in the active layer, physical processes taking place in the bulk of the blend from those at the active layer/contact interfaces. In particular, it is observed that during the ageing experiment, the main source for device performance degradation is the formation of donor–acceptor charge‐transfer complex (–) that acts as an exciton quencher. Generation of these radical species diminishes photocurrent and reduces open‐circuit voltage by the creation of electronic defect states. Conclusions extracted from absorption, C–V, and IS measurements will be further supported by a range of other techniques such as atomic force microscopy, X‐ray diffraction, and dark‐field imaging of scanning transmission electron microscopy on ultrathin cross‐sections. 相似文献
257.
Roscioli E Di Francesco L Bolognesi A Giubettini M Orlando S Harel A Schininà ME Lavia P 《The Journal of cell biology》2012,196(4):435-450
Importin-β is the main vector for interphase nuclear protein import and plays roles after nuclear envelope breakdown. Here we show that importin-β regulates multiple aspects of mitosis via distinct domains that interact with different classes of proteins in human cells. The C-terminal region (which binds importin-α) inhibits mitotic spindle pole formation. The central region (harboring nucleoporin-binding sites) regulates microtubule dynamic functions and interaction with kinetochores. Importin-β interacts through this region with NUP358/RANBP2, which in turn binds SUMO-conjugated RANGAP1 in nuclear pores. We show that this interaction continues after nuclear pore disassembly. Overexpression of importin-β, or of the nucleoporin-binding region, inhibited RANGAP1 recruitment to mitotic kinetochores, an event that is known to require microtubule attachment and the exportin CRM1. Co-expressing either importin-β-interacting RANBP2 fragments, or CRM1, restored RANGAP1 to kinetochores and rescued importin-β-dependent mitotic dynamic defects. These results reveal previously unrecognized importin-β functions at kinetochores exerted via RANBP2 and opposed by CRM1. 相似文献
258.
Genescà M Ma ZM Wang Y Assaf B Qureshi H Fritts L Huang Y McChesney MB Miller CJ 《Journal of virology》2012,86(17):9188-9200
Immunization with attenuated lentiviruses is the only reliable method of protecting rhesus macaques (RM) from vaginal challenge with pathogenic simian immunodeficiency virus (SIV). CD8(+) lymphocyte depletion prior to SIVmac239 vaginal challenge demonstrated that a modest, Gag-specific CD8(+) T cell response induced by immunization with simian-human immunodeficiency virus 89.6 (SHIV89.6) protects RM. Although CD8(+) T cells are required for protection, there is no anamnestic expansion of SIV-specific CD8(+) T cells in any tissues except the vagina after challenge. Further, SHIV immunization increased the number of viral target cells in the vagina and cervix, suggesting that the ratio of target cells to antiviral CD8(+) T cells was not a determinant of protection. We hypothesized that persistent replication of the attenuated vaccine virus modulates inflammatory responses and limits T cell activation and expansion by inducing immunoregulatory T cell populations. We found that attenuated SHIV infection decreased the number of circulating plasmacytoid dendritic cells, suppressed T cell activation, decreased mRNA levels of proinflammatory mediators, and increased mRNA levels of immunoregulatory molecules. Three days after SIV vaginal challenge, SHIV-immunized RM had significantly more T regulatory cells in the vagina than the unimmunized RM. By day 14 postchallenge, immune activation and inflammation were characteristic of unimmunized RM but were minimal in SHIV-immunized RM. Thus, a modest vaccine-induced CD8(+) T cell response in the context of immunoregulatory suppression of T cell activation may protect against vaginal HIV transmission. 相似文献
259.
Cagnacci F Bolzoni L Rosà R Carpi G Hauffe HC Valent M Tagliapietra V Kazimirova M Koci J Stanko M Lukan M Henttonen H Rizzoli A 《International journal for parasitology》2012,42(4):365-372
Tick borne encephalitis (TBE) is endemic to eastern and central Europe with broad temporal and spatial variation in infection risk. Although many studies have focused on understanding the environmental and socio-economic factors affecting exposure of humans to TBE, comparatively little research has been devoted to assessing the underlying ecological mechanisms of TBE occurrence in enzootic cycles, and therefore TBE hazard. The aim of this study was to evaluate the effect of the main ungulate tick hosts on the pattern of tick infestation in rodents and TBE occurrence in rodents and questing adult ticks. In this empirical study, we considered three areas where endemic human TBE occurs and three control sites having no reported human TBE cases. In these six sites located in Italy and Slovakia, we assessed deer density using the pellet group count-plot sampling technique, collected questing ticks, live-trapped rodents (primarily Apodemus flavicollis and Myodes glareolus) and counted ticks feeding on rodents. Both rodents and questing ticks were screened for TBE infection. TBE infection in ticks and rodents was positively associated with the number of co-feeding ticks on rodents and negatively correlated with deer density. We hypothesise that the negative relationship between deer density and TBE occurrence on a local scale (defined by the minimum overlapping area of host species) could be attributed to deer (incompetent hosts) diverting questing ticks from rodents (competent hosts), know as the 'dilution effect hypothesis'. We observed that, after an initial increase, the number of ticks feeding on rodents reached a peak for an intermediate value of estimated deer density and then decreased. Therefore, while at a regional scale, tick host availability has already been shown to be directly correlated with TBE distribution, our results suggest that the interactions between deer, rodents and ticks are much more complex on a local scale, supporting the possibility of a dilution effect for TBE. 相似文献
260.