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991.
Mehdi Menai Léopold Fezeu Hélène Charreire Emmanuelle Kesse-Guyot Mathilde Touvier Chantal Simon Christiane Weber Valentina A. Andreeva Serge Hercberg Jean-Michel Oppert 《PloS one》2014,9(9)
Changes in sedentary behaviours and physical activity according to retirement status need to be better defined. Retirement is a critical life period that may influence a number of health behaviours. We assessed past-year sedentary behaviours (television, computer and reading time during leisure, occupational and domestic sitting time, in h/week) and physical activity (leisure, occupational and domestic, in h/week) over 6 years (2000–2001 and 2007) using the Modifiable Activity Questionnaire in 2,841 participants (mean age: 57.3±5.0 y) of the SU.VI.MAX (Supplementation with Antioxidants and Minerals) cohort. Analyses were performed according to retirement status. Subjects retired in 2001 and 2007 (40%) were those who spent most time in sedentary behaviour and in physical activity during and outside leisure (p<0.001). Leisure-time sedentary behaviours increased in all subjects during follow-up (p<0.001), but subjects who retired between 2001 and 2007 (31%) were those who reported the greatest changes (+8.4±0.42 h/week for a combined indicator of leisure-time sedentary behaviour). They also had the greatest increase in time spent in leisure-time physical activity (+2.5±0.2 h/week). In subjects not retired 2001 and 2007 (29%), changes in time spent watching television were found positively associated with an increase in occupational physical activity (p = 0.04) and negatively associated with changes in leisure-time physical activity (p = 0.02). No consistent association between changes in sedentary behaviours and changes in physical activity was observed in subjects retired in 2001 and 2007. Public health interventions should target retiring age populations not only to encourage physical activity but also to limit sedentary behaviours. 相似文献
992.
Fabio Timeus Nicoletta Crescenzio Daniela Longoni Alessandra Doria Luiselda Foglia Sara Pagliano Stefano Vallero Valentina Decimi Johanna Svahn Giuseppe Palumbo Antonio Ruggiero Baldassarre Martire Marta Pillon Nicoletta Marra Carlo Dufour Ugo Ramenghi Paola Saracco 《PloS one》2014,9(7)
A multicentre study evaluating the presence of glycosil phosphatidyl-inositol (GPI)-negative populations was performed in 85 children with acquired aplastic anemia (AA). A GPI-negative population was observed in 41% of patients at diagnosis, 48% during immune-suppressive therapy (IST), and 45% in patients off-therapy. No association was found between the presence of a GPI-negative population at diagnosis and the response to IST. In addition, the response rate to IST did not differ between the patients who were GPI-positive at diagnosis and later developed GPI-negative populations and the 11 patients who remained GPI-positive. Two patients with a GPI-negative population >10%, and laboratory signs of hemolysis without hemoglobinuria were considered affected by paroxysmal nocturnal hemoglobinuria (PNH) secondary to AA; no thrombotic event was reported. Excluding the 2 patients with a GPI-negative population greater than 10%, we did not observe a significant correlation between LDH levels and GPI-negative population size. In this study monitoring for laboratory signs of hemolysis was sufficient to diagnose PNH in AA patients. The presence of minor GPI-negative populations at diagnosis in our series did not influence the therapeutic response. As occasionally the appearance of a GPI-negative population was observed at cyclosporine (CSA) tapering or AA relapse, a possible role of GPI-negative population monitoring during IST modulation may need further investigation. 相似文献
993.
Valentina Pasqualetti Annamaria Altomare Michele Pier Luca Guarino Vittoria Locato Silvia Cocca Sara Cimini Rossella Palma Rossana Alloni Laura De Gara Michele Cicala 《PloS one》2014,9(5)
Background
Fructans, such as inulin, are dietary fibers which stimulate gastro-intestinal (GI) function acting as prebiotics. Lipopolysaccharide (LPS) impairs GI motility, through production of reactive oxygen species. The antioxidant activity of various fructans was tested and the protective effect of inulin on colonic smooth muscle cell (SMC) impairment, induced by exposure of human mucosa to LPS, was assessed in an ex vivo experimental model.Methods
The antioxidant capacity of fructans was measured in an in vitro system that simulates cooking and digestion processes. Human colonic mucosa and submucosa, obtained from disease-free margins of resected segments for cancer, were sealed between two chambers, with the mucosal side facing upwards with Krebs solution with or without purified LPS from a pathogenic strain of Escherichia coli (O111:B4) and inulin (Frutafit IQ), and the submucosal side facing downwards into Krebs solution. The solutions on the submucosal side were collected following mucosal exposure to Krebs in the absence (N-undernatant) or presence of LPS (LPS-undernatant) or LPS+inulin (LPS+INU-undernatant). Undernatants were tested for their antioxidant activity and the effects on SMCs contractility. Inulin protective effects on mucosa and submucosa layers were assessed measuring the protein oxidation level in the experimental conditions analyzed.Results
Antioxidant activity of inulin, which was significantly higher compared to simple sugars, remained unaltered despite cooking and digestion processes. Inulin protected the mucosal and submucosal layers against protein oxidation. Following exposure to LPS-undernatant, a significant decrease in maximal acetylcholine (Ach)-induced contraction was observed when compared to the contraction induced in cells incubated with the N-undernatant (4±1% vs 25±5% respectively, P<0.005) and this effect was completely prevented by pre-incubation of LPS with Inulin (35±5%).Conclusions
Inulin protects the human colon mucosa from LPS-induced damage and this effect appears to be related to the protective effect of inulin against LPS-induced oxidative stress. 相似文献994.
Fulvio Ricceri Morena Trevisan Valentina Fiano Chiara Grasso Francesca Fasanelli Chiara Scoccianti Laura De Marco Anna Gillio Tos Paolo Vineis Carlotta Sacerdote 《PloS one》2014,9(9)
DNA methylation is a well-characterized epigenetic modification that plays an important role in the regulation of gene expression. There is growing evidence on the involvement of epigenetic mechanisms in disease onset, including cancer. Environmental factors seem to induce changes in DNA methylation affecting human health. However, little is known about basal methylation levels in healthy people and about the correlation between environmental factors and different methylation profiles. We investigated the effect of seasonality on basal methylation by testing methylation levels in the long interspersed nucleotide element-1 (LINE-1) and in two cancer-related genes (RASSF1A and MGMT) of 88 healthy male heavy smokers involved in an Italian randomized study; at enrolment the subjects donated a blood sample collected in different months. Methylation analyses were performed by pyrosequencing. Mean methylation percentage was higher in spring and summer for the LINE1, RASSF1A and MGMT genes (68.26%, 2.35%, and 9.52% respectively) compared with autumn and winter (67.43%, 2.17%, and 8.60% respectively). In particular, LINE-1 was significantly hypomethylated (p = 0.04 or 0.05 depending on the CpG island involved) in autumn and winter compared with spring and summer. Seasonality seems to be a modifier of methylation levels and this observation should be taken into account in future analyses. 相似文献
995.
Valentina A. Andreeva Clotilde Latarche Serge Hercberg Serge Brian?on Pilar Galan Emmanuelle Kesse-Guyot 《PloS one》2014,9(1)
Background
Despite growing attention to nutrition and quality of life in cardiovascular disease survivors, the impact of dietary factors according to disease type or to quality of life domain is poorly understood. We investigated the effects of B vitamin and/or n-3 fatty acid supplementation on health-related quality of life among survivors of stroke, myocardial infarction, or unstable angina.Methods
We performed ancillary analyses of the SU.FOL.OM3 trial (2003–2009; France). In total, 2,501 men (mean age = 61 y) and women (mean age = 63 y) were randomized in a 2×2 factorial design to: 1) 0.56 mg 5-methyl-tetrahydrofolate, 3 mg vitamin B6, 0.02 mg vitamin B12; 2) 600 mg eicosapentaenoic and docosahexaenoic acids in a 2∶1 ratio; 3) B vitamins and n-3 fatty acids combined; or 4) placebo. Health-related quality of life was evaluated at follow-up with the Medical Outcomes Study 36-Item Short Form Health Survey. Data from 2,029 individuals were used in this analysis.Results
After 3.1±0.4 y, no effects of supplementation with either B vitamins or n-3 fatty acids on quality of life (physical or mental health domains) were found. However, participants receiving B vitamins had slightly more activity limitations due to emotional problems compared with those not receiving B vitamins (mean difference = 3.8; 95% CI: 0.4, 7.1). A significant interaction of treatment by prior disease revealed an inverse association between n-3 fatty acids and vitality among myocardial infarction survivors (mean difference = 2.9; 95% CI: 0.5, 5.2).Conclusions
There were no beneficial effects of supplementation with relatively low doses of B vitamins or n-3 fatty acids on health-related quality of life in cardiovascular disease survivors. The adverse effects of B vitamins on activity limitations and of n-3 fatty acids on vitality among individuals with prior myocardial infarction merit confirmation. 相似文献996.
Michela Balestri Marta Barresi Marco Campera Valentina Serra Jean Baptiste Ramanamanjato Michael Heistermann Giuseppe Donati 《PloS one》2014,9(9)
The littoral forest on sandy soil is among the most threatened habitats in Madagascar and, as such, it represents a hot-spot within a conservation hot-spot. Assessing the health of the resident lemur fauna is not only critical for the long-term viability of these populations, but also necessary for the future re-habilitation of this unique habitat. Since the Endangered collared brown lemur, Eulemur collaris, is the largest seed disperser of the Malagasy south-eastern littoral forest its survival in this habitat is crucial. In this study we compared fecal glucocorticoid metabolite (fGCM) levels, a measure of physiological stress and potential early indicator of population health, between groups of collared brown lemurs living in a degraded forest fragment and groups occurring in a more preserved area. For this, we analysed 279 fecal samples collected year-round from 4 groups of collared brown lemurs using a validated 11-oxoetiocholanolone enzyme immunoassay and tested if fGCM levels were influenced by reproductive stages, phenological seasons, sex, and habitat degradation. The lemurs living in the degraded forest had significantly higher fGCM levels than those living in the more preserved area. In particular, the highest fGCM levels were found during the mating season in all animals and in females during gestation in the degraded forest. Since mating and gestation are both occurring during the lean season in the littoral forest, these results likely reflect a combination of ecological and reproductive pressures. Our findings provide a clear indication that habitat degradation has additive effects to the challenges found in the natural habitat. Since increased stress hormone output may have long-term negative effects on population health and reproduction, our data emphasize the need for and may add to the development of effective conservation plans for the species. 相似文献
997.
Evgeniya E. Burkova Pavel S. Dmitrenok Sergey E. Sedykh Valentina N. Buneva Svetlana E. Soboleva Georgy A. Nevinsky 《PloS one》2014,9(11)
Human placenta is an organ which protects, feeds, and regulates the grooving of the embryo. Therefore, identification and characterization of placental components including proteins and their multi-protein complexes is an important step to understanding the placenta function. We have obtained and analyzed for the first time an extremely stable multi-protein complex (SPC, ∼1000 kDa) from the soluble fraction of three human placentas. By gel filtration on Sepharose-4B, the SPC was well separated from other proteins of the placenta extract. Light scattering measurements and gel filtration showed that the SPC is stable in the presence of NaCl, MgCl2, acetonitrile, guanidinium chloride, and Triton in high concentrations, but dissociates efficiently in the presence of 8 M urea, 50 mM EDTA, and 0.5 M NaCl. Such a stable complex is unlikely to be a casual associate of different proteins. According to SDS-PAGE and MALDI mass spectrometry data, this complex contains many major glycosylated proteins with low and moderate molecular masses (MMs) 4–14 kDa and several moderately abundant (79.3, 68.5, 52.8, and 27.2 kDa) as well as minor proteins with higher MMs. The SPC treatment with dithiothreitol led to a disappearance of some protein bands and revealed proteins with lower MMs. The SPCs from three placentas efficiently hydrolyzed plasmid supercoiled DNA with comparable rates and possess at least two DNA-binding sites with different affinities for a 12-mer oligonucleotide. Progress in study of placental protein complexes can promote understanding of their biological functions. 相似文献
998.
Valentina Chiavaroli Maria Loredana Marcovecchio Tommaso de Giorgis Laura Diesse Francesco Chiarelli Angelika Mohn 《PloS one》2014,9(8)
Background
Subjects born small (SGA) and large (LGA) for gestational age have an increased risk of cardio-metabolic alterations already during prepuberty. Nevertheless, the progression of their cardio-metabolic profile from childhood to adolescence has not been fully explored. Our aim was to assess potential changes in the cardio-metabolic profile from childhood to adolescence in subjects born SGA and LGA compared to those born appropriate (AGA) for gestational age.Methods
This longitudinal study included 35 AGA, 24 SGA and 31 LGA subjects evaluated during childhood (mean age (±SD) 8.4±1.4 yr) and then re-assessed during adolescence (mean age 13.3±1.8 yr). BMI, blood pressure, insulin resistance (fasting insulin, HOMA-IR) and lipids were assessed. A cardio-metabolic risk z-score was applied and this consisted in calculating the sum of sex-specific z-scores for BMI, blood pressure, HOMA-IR, triglycerides and triglycerides:high-density lipoprotein cholesterol ratio.Results
Fasting insulin and HOMA-IR were higher in SGA and LGA than AGA subjects both during childhood (all P<0.01) and adolescence (all P<0.01). Similarly, the clustered cardio-metabolic risk score was higher in SGA and LGA than AGA children (both P<0.05), and these differences among groups increased during adolescence (both P<0.05). Of note, a progression of the clustered cardio-metabolic risk score was observed from childhood to adolescence within SGA and within LGA subjects (both P<0.05).Conclusions
SGA and LGA subjects showed an adverse cardio-metabolic profile during childhood when compared to AGA peers, with a worsening of this profile during adolescence. These findings indicate an overtime progression of insulin resistance and overall estimated cardiovascular risk from childhood to adolescence in SGA and LGA populations. 相似文献999.
Excitotoxic damage represents the major mechanism leading to cell death in many human neurodegenerative diseases such as ischemia, trauma and epilepsy. Caused by an excess of glutamate that acts on metabotropic and ionotropic excitatory receptors, excitotoxicity activates several death signaling pathways leading to an extensive neuronal loss and a consequent strong activation of astrogliosis. Currently, the search for a neuroprotective strategy is aimed to identify the level in the signaling pathways to block excitotoxicity avoiding the loss of important physiological functions and side effects. To this aim, PTEN can be considered an ideal candidate: downstream the excitatory receptors activated in excitotoxicity (whose inhibition was shown to be not clinically viable), it is involved in neuronal damage and in the first stage of the reactive astrogliosis in vivo. In this study, we demonstrated the involvement of PTEN in excitotoxicity through its pharmacological inhibition by dipotassium bisperoxo (picolinato) oxovanadate [bpv(pic)] in a model of temporal lobe epilepsy, obtained by intraperitoneal injection of kainate in 2-month-old C57BL/6J male mice. We have demonstrated that inhibition of PTEN by bpv(pic) rescues neuronal death and decreases the reactive astrogliosis in the CA3 area of the hippocampus caused by systemic administration of kainate. Moreover, the neurotoxin administration increases significantly the scanty presence of mitochondrial PTEN that is significantly decreased by the administration of the inhibitor 6 hr after the injection of kainate, suggesting a role of PTEN in mitochondrial apoptosis. Taken together, our results confirm the key role played by PTEN in the excitotoxic damage and the strong anti-inflammatory and neuroprotective potential of its inhibition. 相似文献
1000.
Andrew N. Phillips Valentina Cambiano Fumiyo Nakagawa Deborah Ford Jens D. Lundgren Edith Roset-Bahmanyar Fran?ois Roman Thierry Van Effelterre 《PloS one》2014,9(9)