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71.
Daniel Courteix Jo?o Valente-dos-Santos Béatrice Ferry Gérard Lac Bruno Lesourd Robert Chapier Geraldine Naughton Geoffroy Marceau Manuel Jo?o Coelho-e-Silva Agnès Vinet Guillaume Walther Philippe Obert Frédéric Dutheil 《PloS one》2015,10(9)
Background
Weight loss is a public health concern in obesity-related diseases such as metabolic syndrome (MetS). However, restrictive diets might induce bone loss. The nature of exercise and whether exercise with weight loss programs can protect against potential bone mass deficits remains unclear. Moreover, compliance is essential in intervention programs. Thus, we aimed to investigate the effects that modality and exercise compliance have on bone mineral content (BMC) and density (BMD).Methods
We investigated 90 individuals with MetS who were recruited for the 1-year RESOLVE trial. Community-dwelling seniors with MetS were randomly assigned into three different modalities of exercise (intensive resistance, intensive endurance, moderate mixed) combined with a restrictive diet. They were compared to 44 healthy controls who did not undergo the intervention.Results
This intensive lifestyle intervention (15–20 hours of training/week + restrictive diet) resulted in weight loss, body composition changes and health improvements. Baseline BMC and BMD for total body, lumbar spine and femoral neck did not differ between MetS groups and between MetS and controls. Despite changes over time, BMC or BMD did not differ between the three modalities of exercise and when compared with the controls. However, independent of exercise modality, compliant participants increased their BMC and BMD compared with their less compliant peers. Decreases in total body lean mass and negative energy balance significantly and independently contributed to decreases in lumbar spine BMC.Conclusion
After the one year intervention, differences relating to exercise modalities were not evident. However, compliance with an intensive exercise program resulted in a significantly higher bone mass during energy restriction than non-compliance. Exercise is therefore beneficial to bone in the context of a weight loss program.Trial Registration
ClinicalTrials.gov NCT00917917 相似文献72.
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74.
Classification of human chromosome 21 gene-expression variations in Down syndrome: impact on disease phenotypes 总被引:5,自引:0,他引:5 下载免费PDF全文
75.
Flavonoid accumulation in Arabidopsis repressed in lignin synthesis affects auxin transport and plant growth 总被引:2,自引:0,他引:2 下载免费PDF全文
In Arabidopsis thaliana, silencing of hydroxycinnamoyl-CoA shikimate/quinate hydroxycinnamoyl transferase (HCT), a lignin biosynthetic gene, results in a strong reduction of plant growth. We show that, in HCT-silenced plants, lignin synthesis repression leads to the redirection of the metabolic flux into flavonoids through chalcone synthase activity. Several flavonol glycosides and acylated anthocyanin were shown to accumulate in higher amounts in silenced plants. By contrast, sinapoylmalate levels were barely affected, suggesting that the synthesis of that phenylpropanoid compound might be HCT-independent. The growth phenotype of HCT-silenced plants was shown to be controlled by light and to depend on chalcone synthase expression. Histochemical analysis of silenced stem tissues demonstrated altered tracheary elements. The level of plant growth reduction of HCT-deficient plants was correlated with the inhibition of auxin transport. Suppression of flavonoid accumulation by chalcone synthase repression in HCT-deficient plants restored normal auxin transport and wild-type plant growth. By contrast, the lignin structure of the plants simultaneously repressed for HCT and chalcone synthase remained as severely altered as in HCT-silenced plants, with a large predominance of nonmethoxylated H units. These data demonstrate that the reduced size phenotype of HCT-silenced plants is not due to the alteration of lignin synthesis but to flavonoid accumulation. 相似文献
76.
Stéphanie Loyaux-Lawniczak Stéphane Vuilleumier Valérie A. Geoffroy 《Geomicrobiology journal》2019,36(5):423-432
The genus Paenibacillus was hardly described as a Fe(III)-reducing agent, only limited to reduce soluble forms or Fe inserted in poorly crystallized structures. In this study, three Paenibacillus strains capable of reducing manganese oxides in addition to iron oxides were isolated from Cameroonian and Brazilian soils. These strains reduced iron minerals from poorly crystallized 2-line ferrihydrite to well-crystallized Al-substituted and pure goethite with a significant production of soluble ferrous iron. These Paenibacillus strains, inhabitants from ferralitic temporarily waterlogged soils, could play an important role in the bioweathering of minerals and metal mobility in soils. 相似文献
77.
In the Oriental Region, the large, basically Northern Hemisphere family Trichopolydesmidae is shown to currently comprise 18 genera and 43 species. Based mainly on gonopod structure, all of them, as well as the whole family, are (re)diagnosed, including five new genera and seven new species. These new taxa are keyed, also being the first to be described from Indochina in general and from Vietnam in particular: Aporodesmella
gen. n., with three species: A. securiformis
sp. n. (the type species), A. similis
sp. n. and A. tergalis
sp. n., as well as the following four monotypic genera: Deharvengius
gen. n., with D. bedosae
sp. n., Gonatodesmus
gen. n., with G. communicans
sp. n., Helicodesmus
gen. n., with H. anichkini
sp. n., and Monstrodesmus
gen. n., with M. flagellifer
sp. n. In addition, Cocacolaria hauseri Hoffman, 1987, hitherto known only from New Ireland Island, Papua New Guinea, is redescribed based on material from Vanuatu whence it is recorded for the first time. One of the new genera, Gonatodesmus
gen. n., provides a kind of transition or evolutionary bridge between Trichopolydesmidae and Opisotretidae, thus reinforcing the assignment of these two families to the single superfamily Trichopolydesmoidea. 相似文献
78.
Mohsen Kayal Julie Vercelloni Thierry Lison de Loma Pauline Bosserelle Yannick Chancerelle Sylvie Geoffroy Céline Stievenart Fran?ois Michonneau Lucie Penin Serge Planes Mehdi Adjeroud 《PloS one》2012,7(10)
Outbreaks of the coral-killing seastar Acanthaster planci are intense disturbances that can decimate coral reefs. These events consist of the emergence of large swarms of the predatory seastar that feed on reef-building corals, often leading to widespread devastation of coral populations. While cyclic occurrences of such outbreaks are reported from many tropical reefs throughout the Indo-Pacific, their causes are hotly debated, and the spatio-temporal dynamics of the outbreaks and impacts to reef communities remain unclear. Based on observations of a recent event around the island of Moorea, French Polynesia, we show that Acanthaster outbreaks are methodic, slow-paced, and diffusive biological disturbances. Acanthaster outbreaks on insular reef systems like Moorea''s appear to originate from restricted areas confined to the ocean-exposed base of reefs. Elevated Acanthaster densities then progressively spread to adjacent and shallower locations by migrations of seastars in aggregative waves that eventually affect the entire reef system. The directional migration across reefs appears to be a search for prey as reef portions affected by dense seastar aggregations are rapidly depleted of living corals and subsequently left behind. Coral decline on impacted reefs occurs by the sequential consumption of species in the order of Acanthaster feeding preferences. Acanthaster outbreaks thus result in predictable alteration of the coral community structure. The outbreak we report here is among the most intense and devastating ever reported. Using a hierarchical, multi-scale approach, we also show how sessile benthic communities and resident coral-feeding fish assemblages were subsequently affected by the decline of corals. By elucidating the processes involved in an Acanthaster outbreak, our study contributes to comprehending this widespread disturbance and should thus benefit targeted management actions for coral reef ecosystems. 相似文献
79.
Prat C Blanchon L Borel V Gallot D Herbet A Bouvier D Marceau G Sapin V 《Biology of reproduction》2012,86(2):48
It has been proposed that four members of the aquaporin family (AQPs 1, 3, 8, and 9) are involved in the control of amniotic fluid (AF) homeostasis, as illustrated by their differential expression patterns in normal and pathological human term fetal membranes. However, there are no data available to date on their ontogeny throughout pregnancy. Our objective was to determine spatiotemporal expression profiles of the mRNA and proteins of all 13 members of this transmembrane channel family. For this purpose, we used healthy fetal membranes from the first, second, and third trimesters of pregnancy. Total mRNA and proteins were extracted from total membranes and from separated amnion and chorion. Quantitative PCR, Western blot, and immunohistochemistry experiments were carried out to determine the presence of AQPs and to quantify their spatiotemporal expression patterns throughout pregnancy. The WISH cell line was tested to propose a cellular model for the role of AQPs in the amnion compartment. AQP11 expression was established in amniotic membranes at term. Aquaporins 1, 3, 8, 9, and 11 mRNA and proteins were present in amnion and chorion throughout human gestation. Each AQP has a time-specific expression pattern, with AQP1 presenting the highest variation in terms of mRNA and protein levels. The WISH cell line also expressed the same five AQPs. Taken together, these results indicate that AQPs are expressed and potentially involved in the regulation of AF homeostasis throughout pregnancy. This also clearly supports the hypothesis that abnormal expression could occur at any time during pregnancy, ultimately leading to obstetrical pathologies such as polyhydramnios or oligohydramnios. 相似文献
80.