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GeroScience - When tracing a template with mirror-reversed vision (or distorted vision), the sensory information arising from the movement does not match the expected sensory consequences. In such...  相似文献   
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Anemia represents a global health problem that negatively impacts quality of life in elderly population; however, its impact on the geriatric syndrome of frailty is unclear. We examined the prevalence of anemia among elderly and sought a relationship between hemoglobin and the phenotype of frailty. Baseline hemoglobin quintiles and anemia were assessed in relation to frailty status in a prospective study with 1,933 older community-dwelling adults enrolled in the Study on Aging and Dementia in Mexico (SADEM). Logistic regression was used to model the relationship between frailty and Hb, adjusting for risk factors of frailty, sociodemographic data, cognitive decline, chronic diseases, and some risky habits. Prevalence of frailty was 8.3 %. Frailty risk was highest at the lowest hemoglobin quintile (<14.3 g/dL for men; <13.3 g/dL for women), and 160 (8.3 %) were anemic (<13 g/dL for men; <12 g/dL for women). The relationship between frailty and Hb levels, adjusted for age and sex, observed in the first and fifth quintiles, compared with the fourth quintile, were 1.53 (95 % confidence interval (CI), 1.46–1.60) and 1.05 (95 % CI, 1.01–1.15). After multivariate adjustment, the odds ratios (ORs) were 1.23 (95 % CI, 1.17–1.13) and 1.06 (95 % CI, 1.01–1.11). The association was not diminished by risk factors for frailty (body mass index (BMI), comorbidity, cognitive decline, smoking, alcohol consumption, etc.). In community-dwelling older adults, low hemoglobin concentrations and anemia were independently associated with increased frailty risk. This suggests that mild anemia and low Hb levels are independent, modifiable risk factors for frailty.  相似文献   
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Lactobacillus johnsonii NCC 533 is a member of the acidophilus group of intestinal lactobacilli that has been extensively studied for their "probiotic" activities that include, pathogen inhibition, epithelial cell attachment, and immunomodulation. To gain insight into its physiology and identify genes potentially involved in interactions with the host, we sequenced and analyzed the 1.99-Mb genome of L. johnsonii NCC 533. Strikingly, the organism completely lacked genes encoding biosynthetic pathways for amino acids, purine nucleotides, and most cofactors. In apparent compensation, a remarkable number of uncommon and often duplicated amino acid permeases, peptidases, and phosphotransferase-type transporters were discovered, suggesting a strong dependency of NCC 533 on the host or other intestinal microbes to provide simple monomeric nutrients. Genome analysis also predicted an abundance (>12) of large and unusual cell-surface proteins, including fimbrial subunits, which may be involved in adhesion to glycoproteins or other components of mucin, a characteristic expected to affect persistence in the gastrointestinal tract (GIT). Three bile salt hydrolases and two bile acid transporters, proteins apparently critical for GIT survival, were also detected. In silico genome comparisons with the >95% complete genome sequence of the closely related Lactobacillus gasseri revealed extensive synteny punctuated by clear-cut insertions or deletions of single genes or operons. Many of these regions of difference appear to encode metabolic or structural components that could affect the organisms competitiveness or interactions with the GIT ecosystem.  相似文献   
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