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141.
Allan Garland Clare D. Ramsey Randy Fransoo Kendiss Olafson Daniel Chateau Marina Yogendran Allen Kraut 《CMAJ》2013,185(14):1207-1214
Background:
Leaving hospital against medical advice may have adverse consequences. Previous studies have been limited by evaluating specific types of patients, small sample sizes and incomplete determination of outcomes. We hypothesized that leaving hospital against medical advice would be associated with increases in subsequent readmission and death.Methods:
In a population-based analysis involving all adults admitted to hospital and discharged alive in Manitoba from Apr. 1, 1990, to Feb. 28, 2009, we evaluated all-cause 90-day mortality and 30-day hospital readmission. We used multivariable regression, adjusted for age, sex, socioeconomic status, year of hospital admission, patient comorbidities, hospital diagnosis, past frequency of admission to hospital, having previously left hospital against medical advice and data clustering (patients with multiple admissions). For readmission, we assessed both between-person and within-person effects of leaving hospital against medical advice.Results:
Leaving against medical advice occurred in 21 417 of 1 916 104 index hospital admissions (1.1%), and was associated with higher adjusted rates of 90-day mortality (odds ratio [OR] 2.51, 95% confidence interval [CI] 2.18–2.89), and 30-day hospital readmission (within-person OR 2.10, CI 1.99–2.21; between-person OR 3.04, CI 2.79–3.30). In our additional analyses, elevated rates of readmission and death associated with leaving against medical advice were manifest within 1 week and persisted for at least 180 days after discharge.Interpretation:
Adults who left the hospital against medical advice had higher rates of hospital readmission and death. The persistence of these effects suggests that they are not solely a result of incomplete treatment of acute illness. Interventions aimed at reducing these effects may need to include longitudinal interventions extending beyond admission to hospital.Patients leaving hospital against medical advice have been discussed in the medical literature for more than 50 years.1 Reported to occur in 1%–2% of patients in general hospitals,2,3 the numbers are large; in the United States, 368 000 patients left against medical advice in 2007,3 and rates higher than 10% have been documented in certain subgroups, including Canadian patients with HIV and predominantly poor residents of inner city areas.4,5 The main concern over leaving hospital against medical advice is that it may increase morbidity or mortality. Previous studies attempting to assess this effect2,4–13 have all been restricted to specific types of patients, and most studies were limited by small sample sizes and incomplete determination of outcomes. In this study, we used data that avoided these limitations to test the hypothesis that patients who leave hospital against medical advice have higher rates of hospital readmission and death. 相似文献142.
Dr. Fabienne Aujard Florence Cayetanot Marina Bentivoglio Martine Perret 《Chronobiology international》2013,30(1-2):451-460
In humans, activity rhythms become fragmented and attenuated in the elderly. This suggests an alteration of the circadian system per se that could in turn affect the expression of biological rhythms. In primates, very few studies have analyzed the effect of aging on the circadian system. The mouse lemur provides a unique model of aging in non‐human primates. To assess the effect of aging on the circadian system of this primate, we recorded the circadian and daily rhythms of locomotor activity of mouse lemurs of various ages. We also examined age‐related changes in the daily rhythm of immunoreactivities for vasoactive intestinal polypeptide (VIP) and arginine‐vasopressin (AVP) in suprachiasmatic nucleus neurons (SCN), two major peptides of the biological clock. Compared to adult animals, aged mouse lemurs showed a significant increase in daytime activity and an advanced activity onset. Moreover, when maintained in constant dim red light, aged animals exhibited a shortening of the free‐running period compared to adult animals. In adults, AVP immunoreactivity (ir) peaked during the second part of the day, and VIP ir peaked during the night. In aged mouse lemurs, the peaks of AVP ir and VIP ir were significantly shifted with no change in amplitude. AVP ir was most intense at the beginning of the night; whereas, VIP ir peaked at the beginning of the daytime. A weakened oscillator could account for the rhythmic disorders often observed in the elderly. Changes in the daily rhythms of AVP ir and VIP ir may affect the ability of the SCN to transmit rhythmic information to other neural target sites, and thereby modify the expression of some biological rhythms. 相似文献
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144.
Luca Madaro Fabrizio Antonangeli Annarita Favia Bianca Esposito Filippo Biamonte Marina Bouché Elio Ziparo Gigliola Sica Antonio Filippini Alessio D'Alessio 《Journal of cellular biochemistry》2013,114(8):1843-1851
Caveolin‐1 (CAV1) is the principal structural component of caveolae which functions as scaffolding protein for the integration of a variety of signaling pathways. In this study, we investigated the involvement of CAV1 in endothelial cell (EC) functions and show that siRNA‐induced CAV1 silencing in the human EC line EA.hy926 induces distinctive morphological changes, such as a marked increase in cell size and formation of stress fibers. Design‐based stereology was employed in this work to make unbiased quantification of morphometric properties such as volume, length, and surface of CAV1 silenced versus control cells. In addition, we showed that downregulation of CAV1 affects cell cycle progression at G1/S phase transition most likely by perturbation of AKT signaling. With the aim to assess the contribution of CAV1 to typical biological processes of EC, we report here that CAV1 targeting affects cell migration and matrix metalloproteinases (MMPs) activity, and reduces angiogenesis in response to VEGF, in vitro. Taken together our data suggest that the proper expression of CAV1 is important not only for maintaining the appropriate morphology and size of ECs but it might represent a prospective molecular target for studying key biological mechanisms such as senescence and tumorigenesis. J. Cell. Biochem. 114: 1843–1851, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
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146.
Tania Fernandes Campos Aline Braga Galvão Silveira Marina Tostes Miranda Barroso 《Chronobiology international》2013,30(4):611-624
Various studies have been performed using the Social Rhythm Metric (SRM), though none has been developed with stroke patients. Stroke is a pathology that provokes a strong physical and social impact caused by an abnormality in cerebral circulation. Consequently, we performed two studies to validate the SRM and translate it into Portuguese, and to evaluate the regularity of the daily activities of stroke patients. Both healthy individuals and patients with unilateral cerebral lesions were evaluated. Subjects were of both sexes and between 45 and 65 yrs of age. Participants underwent clinical evaluation and recorded the time of 17 daily activities on the SRM for two weeks. Data were analyzed by the Pearson correlation and Fisher tests. After conceptual translation into Portuguese, corrections were made to arrive at the final version. Normative SRM scores varied from 3.2 to 7.0, suggesting that the activities presented in SRM adequately represented the daily routines of the patients. A correlation was found in SRM between the weeks (r=0.84; p=0.0001), indicating instrument reliability. The mean (±SD) score of the stoke patients was 4.8 (±1.0), and the correlation between the SRM and level of neurological damage showed that patients with lower SRM values were more physically compromised (r=?0.29; p=0.04), suggesting that SRM may be a clinical predictor. Activities related to eating and the sleep‐wake cycle were rated by most patients. In all, 71% of the patients did not work, while 84% of healthy individuals did (p=0.001). Only 64% of patients left home compared to 90% of the healthy subjects (p=0.001), and 59% of patients recorded the activity of going home compared to 82% of healthy individuals (p=0.001). According to the results, there is evidence of the validity and reliability of the SRM, enabling it to be reliably used in chronobiological studies of stroke patients. Given that a less regular lifestyle may be associated with neurological compromise and a decrease in social activities, we suggest new studies with the repeated application of this instrument over the clinical evolution of the disease to better define improvement or worsening of the patient's condition in terms of their social and health aspects. 相似文献
147.
148.
Svetlana V. Osipova Aleksey V. Permyakov Marina D. Permyakova Tatyana A. Pshenichnikova Mikhail A. Genaev Andreas Börner 《Acta Physiologiae Plantarum》2013,35(8):2455-2465
Understanding of the genetic basis of physiological properties, which are most relevant to water-deficit tolerance would be helpful for genomic-assisted improvement of bread wheat. A set of bread wheat inter-varietal single chromosome substitution lines (ISCSLs) of variety ‘Janetzkis Probat’ (JP) in the genetic background of ‘Saratovskaya’ 29 (S29) were used to reveal the critical chromosomes in wheat genome controlling tolerance to water deficit. The same lines were involved in the identification of chromosomes associated with the activity of antioxidant enzymes that are closely related to the detoxification of H2O2 [catalase (CAT), ascorbate peroxidase, dehydroascorbate reductase and glutathione reductase (GR)]. The recipient cultivar S29 was highly drought tolerant while the donor JP was sensitive. Using non-metric multidimensional scaling of yield components and indices of drought tolerance/susceptibility chromosomes 2A and 4D, substitution in the genetic background of S29 was found to lead to a critical decrease of water-deficit tolerance. The drop of tolerance correlated with a sharp decline of cumulative activity of the catalase and the enzymes of ascorbate–glutathione cycle in wheat leaves. Clear evidence was obtained for the involvement of genes present on the homoeologous group 2 chromosomes in the control of GR and CAT activity. Substitution of the chromosome 4D had a significant reducing impact on the CAT activity level. 相似文献
149.
Mammalian target of rapamycin (mTOR) is a major intersection that connects signals from the extracellular milieu to corresponding changes in intracellular processes. When abnormally regulated, the mTOR signaling pathway is implicated in a wide spectrum of cancers, neurological diseases, and proliferative disorders. Therefore, pharmacological agents that restore the regulatory balance of the mTOR pathway could be beneficial for a great number of diseases. This review summarizes current understanding of mTOR signaling and some unanswered questions in the field. We describe the composition of the mTOR complexes, upstream signals that activate mTOR, and physiological processes that mTOR regulates. We also discuss the role of mTOR and its downstream effectors in cancer, obesity and diabetes, and autism. J. Cell. Physiol. 228: 1658–1664, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
150.