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排序方式: 共有832条查询结果,搜索用时 15 毫秒
91.
Ugo Lucca Mariateresa Garrì Angela Recchia Giancarlo Logroscino Pietro Tiraboschi Massimo Franceschi Chiara Bertinotti Anna Biotti Elena Gargantini Marilena Maragna Alessandro Nobili Luca Pasina Carlotta Franchi Emma Riva Mauro Tettamanti 《BMC neurology》2011,11(1):1-14
Background
Despite being the fastest growing and the most cognitively impaired age group, the oldest olds are under-represented in clinical research. The purpose of this study was to describe the design, methods, and baseline characteristics of the survey population and investigate possible differences in demographic, cognitive, functional, and behavioral characteristics between oldest old with and without any performance on cognitive tests and between oldest old alive and those deceased prior to the interview.Methods
The Monzino 80-plus Study is a prospective door-to-door population-based survey among 80 years or older residents in the municipalities in the province of Varese, Italy. Dementia cases were identified with a one-phase design. Trained psychologists interviewed both the subject and a proxy informant. The interview included a comprehensive standardized questionnaire together with an array of rating scales and a multidomain cognitive battery to assess cognitive and functional ability, behavioral disturbances and mood.Results
Information was available for 2,139 of the 2,428 registered individuals aged 80 years or older. Main baseline characteristics of the population are reported and discussed. In comparison with those living, elderly persons who had died before the first visit were older, had twice the rate of institutionalization, poorer cognitive performance and competence, and significantly greater instrumental and basic functional disability. The percentage of elderly persons, alive at baseline, without Mini-Mental State Examination rose rather evenly with age. Moreover, they had significantly worse cognitive competence and functional ability, and reported higher prevalences of depressive symptoms and problem behaviors than those with Mini-Mental State Examination.Conclusions
Prospective investigation of a large population of oldest old can contribute significantly to understanding the relations between age, cognitive decline, and dementia occurrence. Use of informant-based instruments in surveys in the oldest old is crucial in assessing everyday functioning and changes, especially in participants with no cognitive test performance available. Failure to include information on deceased elderly would underestimate, increasingly with age, the prevalence of cognitive and functional disability in the elderly population. 相似文献92.
Stella R Biancotto G Krogh M Angeletti R Pozza G Sorgato MC James P Andrighetto I 《Journal of proteome research》2011,10(6):2744-2757
The fraudulent treatment of cattle with growth promoting agents (GPAs) is a matter of great concern for the European Union (EU) authorities and consumers. It has been estimated that 10% of animals are being illegally treated in the EU. In contrast, only a much lower percentage of animals (<0.5%) are actually found as being noncompliant by conventional analytical methods. Thus, it has been proposed that methods should be developed that can detect the use of the substances via the biological effects of these substances on target organs, such as the alteration of protein expression profiles. Here we present a study aimed at evaluating if a correlation exists between the treatment with GPAs and alterations in the two-dimensional electrophoresis (2DE) protein pattern obtained from the biceps brachii skeletal muscle from mixed-bred cattle. After image analysis and statistical evaluation, protein spots that differentiate between treated and control groups were selected for analysis by mass spectrometry. A set of proteins could be defined that accurately detect the use of glucocorticoids and β(2)-agonists as growth promoters through the changes caused in muscle differentiation. As a further validation, we repeated the analysis using an independent set of samples from a strain of pure-bred cattle and verified these proteins by Western blot analysis. 相似文献
93.
Gabriele Alfano Giuseppe Lustrato Giuseppe Lima Domenico Vitullo Giancarlo Ranalli 《Biological Control》2011,58(3):199-207
Despite its proven agronomic value, the plant disease suppressive effect of composts from olive waste has not been adequately investigated. In the present study, the disease suppressive potential of two olive waste (OW) composts against soil-borne plant pathogens was investigated. Both OW composts showed sizeable, active microbial populations, which were able to grow actively on chitin and cellulose. In plate inhibition trials, OW compost water extracts (CWEs) exerted a significant inhibitory effect on the growth of the pathogens Fusarium oxysporum f.sp. lycopersici (Fol), Pythium ultimum, Phytophtora infestans, Sclerotina sclerotiorum and Verticillium dahliae; and in pot experiments, the OW composts significantly reduced P. ultimum damping-off and Fol wilt diseases on tomato seedlings. The disease suppressive effect of OW composts seems to be due to the combined effects of suppression phenomena caused by the presence of microorganisms competing for both nutrients and space as well as by the activity of specific antagonistic microorganisms. 相似文献
94.
Sanna D Pala M Cossu P Dedola GL Melis S Fresu G Morelli L Obinu D Tonolo G Secchi G Triunfo R Lorenz JG Scheinfeldt L Torroni A Robledo R Francalacci P 《Genetics and molecular biology》2011,34(2):187-194
We report a sampling strategy based on Mendelian Breeding Units (MBUs), representing an interbreeding group of individuals sharing a common gene pool. The identification of MBUs is crucial for case-control experimental design in association studies. The aim of this work was to evaluate the possible existence of bias in terms of genetic variability and haplogroup frequencies in the MBU sample, due to severe sample selection. In order to reach this goal, the MBU sampling strategy was compared to a standard selection of individuals according to their surname and place of birth. We analysed mitochondrial DNA variation (first hypervariable segment and coding region) in unrelated healthy subjects from two different areas of Sardinia: the area around the town of Cabras and the western Campidano area. No statistically significant differences were observed when the two sampling methods were compared, indicating that the stringent sample selection needed to establish a MBU does not alter original genetic variability and haplogroup distribution. Therefore, the MBU sampling strategy can be considered a useful tool in association studies of complex traits. 相似文献
95.
Marinaro C Butti E Bergamaschi A Papale A Furlan R Comi G Martino G Muzio L 《PloS one》2011,6(4):e19419
Radial Glia (RG) cells constitute the major population of neural progenitors of the mouse developing brain. These cells are located in the ventricular zone (VZ) of the cerebral cortex and during neurogenesis they support the generation of cortical neurons. Later on, during brain maturation, RG cells give raise to glial cells and supply the adult mouse brain of Neural Stem Cells (NSC). Here we used a novel transgenic mouse line expressing the CreER(T2) under the control of AspM promoter to monitor the progeny of an early cohort of RG cells during neurogenesis and in the post natal brain. Long term fate mapping experiments demonstrated that AspM-expressing RG cells are multi-potent, as they can generate neurons, astrocytes and oligodendrocytes of the adult mouse brain. Furthermore, AspM descendants give also rise to proliferating progenitors in germinal niches of both developing and post natal brains. In the latter--i.e. the Sub Ventricular Zone--AspM descendants acquired several feature of neural stem cells, including the capability to generate neurospheres in vitro. We also performed the selective killing of these early progenitors by using a Nestin-GFP(flox)-TK allele. The forebrain specific loss of early AspM expressing cells caused the elimination of most of the proliferating cells of brain, a severe derangement of the ventricular zone architecture, and the impairment of the cortical lamination. We further demonstrated that AspM is expressed by proliferating cells of the adult mouse SVZ that can generate neuroblasts fated to become olfactory bulb neurons. 相似文献
96.
Cobellis G Nicolaus G Iovino M Romito A Marra E Barbarisi M Sardiello M Di Giorgio FP Iovino N Zollo M Ballabio A Cortese R 《Nucleic acids research》2005,33(4):e44
In an effort to make transgenesis more flexible and reproducible, we developed a system based on novel 5′ and 3′ ‘gene trap’ vectors containing heterospecific Flp recognition target sites and the corresponding ‘exchange’ vectors allowing the insertion of any DNA sequence of interest into the trapped locus. Flp-recombinase-mediated cassette exchange was demonstrated to be highly efficient in our system, even in the absence of locus-specific selection. The feasibility of constructing a library of ES cell clones using our gene trap vectors was tested and a thousand insertion sites were characterized, following electroporation in ES cells, by RACE–PCR and sequencing. We validated the system in vivo for two trapped loci in transgenic mice and demonstrated that the reporter transgenes inserted into the trapped loci have an expression pattern identical to the endogenous genes. We believe that this system will facilitate in vivo studies of gene function and large-scale generation of mouse models of human diseases, caused by not only loss but also gain of function alleles. 相似文献
97.
Rossetti L Franceschin M Schirripa S Bianco A Ortaggi G Savino M 《Bioorganic & medicinal chemistry letters》2005,15(2):413-420
While the importance of the aromatic core in small organic molecules, studied as G-quadruplex mediated telomerase inhibitors, appears well studied by a number of researches, the role of side chains has been less well characterized. In this paper, we have studied the ability of six perylene derivatives with different side chains to induce both inter- and intramolecular G-quadruplex structures. The distance between the aromatic core and the positive charges in the side chains emerges as a significant molecular feature in G-quadruplex formation. Furthermore, the G-quadruplex formation appears also related to drugs 'self-association', influenced by the side chains basicity. The different efficiencies of the six perylene derivatives in interacting both with inter- and intramolecular G-quadruplex structures satisfactorily correlate with telomerase inhibition in cell-free systems. 相似文献
98.
Falchetti A Di Stefano M Marini F Del Monte F Gozzini A Masi L Tanini A Amedei A Carossino A Isaia G Brandi ML 《Arthritis research & therapy》2005,7(6):R1289-R1295
Mutations of the p62/Sequestosome 1 gene (p62/SQSTM1) account for both sporadic and familial forms of Paget's disease of bone (PDB). We originally described a methionine-->valine substitution at codon 404 (M404V) of exon 8, in the ubiquitin protein-binding domain of p62/SQSTM1 gene in an Italian PDB patient. The collection of data from the patient's pedigree provided evidence for a familial form of PDB. Extension of the genetic analysis to other relatives in this family demonstrated segregation of the M404V mutation with the polyostotic PDB phenotype and provided the identification of six asymptomatic gene carriers. DNA for mutational analysis of the exon 8 coding sequence was obtained from 22 subjects, 4 PDB patients and 18 clinically unaffected members. Of the five clinically ascertained affected members of the family, four possessed the M404V mutation and exhibited the polyostotic form of PDB, except one patient with a single X-ray-assessed skeletal localization and one with a polyostotic disease who had died several years before the DNA analysis. By both reconstitution and mutational analysis of the pedigree, six unaffected subjects were shown to bear the M404V mutation, representing potential asymptomatic gene carriers whose circulating levels of alkaline phosphatase were recently assessed as still within the normal range. Taken together, these results support a genotype-phenotype correlation between the M404V mutation in the p62/SQSTM1 gene and a polyostotic form of PDB in this family. The high penetrance of the PDB trait in this family together with the study of the asymptomatic gene carriers will allow us to confirm the proposed genotype-phenotype correlation and to evaluate the potential use of mutational analysis of the p62/SQSTM1 gene in the early detection of relatives at risk for PDB. 相似文献
99.
Expanding the proteome two-dimensional gel electrophoresis reference map of human renal cortex by peptide mass fingerprinting 总被引:1,自引:0,他引:1
Magni F Sarto C Valsecchi C Casellato S Bogetto SF Bosari S Di Fonzo A Perego RA Corizzato M Doro G Galbusera C Rocco F Mocarelli P Galli Kienle M 《Proteomics》2005,5(3):816-825
Proteomics methodologies hold great promise in basic renal research and clinical nephrology. The classical approach for proteomic analysis couples two-dimensional gel electrophoresis (2-DE) with protein identification by mass spectrometry, to produce more global information regarding normal protein expression and alterations in different physiological and pathological states. In this report we have expanded the identification of proteins in the renal cortex, improving the previously published map to facilitate the study of different diseases affecting the human kidney. About 250 spots were analyzed by peptide mass fingerprinting, 89 proteins and 74 isoforms for some of them were identified and implemented in the normal human renal cortex 2-DE reference map. This more comprehensive view of the proteome of the human renal cortex could be of invaluable help to the differential proteomic display of urological diseases. 相似文献