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31.

Objectives

Lifestyle combined interventions are a key strategy for preventing type-2 diabetes (T2DM) in overweight or obese subjects. In this framework, LIPOXmax individualized training, based on maximal fat oxidation [MFO], may be a promising intervention to promote fat mass (FM) reduction and prevent T2DM. Our primary objective was to compare three training programs of physical activity combined with a fruit- and vegetable-rich diet in reducing FM in overweight or obese women.

Design and setting

A five months non-blinded randomized controlled trial (RCT) with three parallel groups in La Réunion Island, a region where metabolic diseases are highly prevalent.

Subjects

One hundred and thirty-six non-diabetic obese (body mass index [BMI]: 27–40 kg/m2) young women (aged 20–40) were randomized (G1: MFO intensity; G2: 60% of VO2-peak intensity; G3: free moderate-intensity at-home exercise following good physical practices).

Outcomes

Anthropometry (BMI, bodyweight, FM, fat-free mass), glucose (fasting plasma glucose, insulin, HOMA-IR) and lipid (cholesterol and triglycerides) profiles, and MFO values were measured at month-0, month-3 and month-5.

Results

At month-5, among 109 women assessed on body composition, the three groups exhibited a significant FM reduction over time (G1: -4.1±0.54 kg; G2: -4.7±0.53 kg; G3: -3.5±0.78 kg, p<0.001, respectively) without inter-group differences (p = 0.135). All groups exhibited significant reductions in insulin levels or HOMA-IR index, and higher MFO values over time (p<0.001, respectively) but glucose control improvement was higher in G1 than in G3 while MFO values were higher in G1 than in G2 and G3. Changes in other outcome measures and inter-group differences were not significant.

Conclusion

In our RCT the LIPOXmax intervention did not show a superiority in reducing FM in overweight or obese women but is associated with higher MFO and better glucose control improvements. Other studies are required before proposing LIPOXmax training for the prevention of T2DM in overweight or obese women.

Trial Registration

ClincialTrials.gov NCT01464073  相似文献   
32.

Background and Aims

Nutritional changes associated with the evolution of achlorophyllous, mycoheterotrophic plants have not previously been inferred with robust phylogenetic hypotheses. Variations in heterotrophy in accordance with the evolution of leaflessness were examined using a chlorophyllous–achlorophyllous species pair in Cymbidium (Orchidaceae), within a well studied phylogenetic background.

Methods

To estimate the level of mycoheterotrophy in chlorophyllous and achlorophyllous Cymbidium, natural 13C and 15N contents (a proxy for the level of heterotrophy) were measured in four Cymbidium species and co-existing autotrophic and mycoheterotrophic plants and ectomycorrhizal fungi from two Japanese sites.

Key Results

δ13C and δ15N values of the achlorophyllous C. macrorhizon and C. aberrans indicated that they are full mycoheterotrophs. δ13C and δ15N values of the chlorophyllous C. lancifolium and C. goeringii were intermediate between those of reference autotrophic and mycoheterotrophic plants; thus, they probably gain 30–50 % of their carbon resources from fungi. These data suggest that some chlorophyllous Cymbidium exhibit partial mycoheterotrophy (= mixotrophy).

Conclusions

It is demonstrated for the first time that mycoheterotrophy evolved after the establishment of mixotrophy rather than through direct shifts from autotrophy to mycoheterotrophy. This may be one of the principal patterns in the evolution of mycoheterotrophy. The results also suggest that the establishment of symbiosis with ectomycorrhizal fungi in the lineage leading to mixotrophic Cymbidium served as pre-adaptation to the evolution of the mycoheterotrophic species. Similar processes of nutritional innovations probably occurred in several independent orchid groups, allowing niche expansion and radiation in Orchidaceae, probably the largest plant family.  相似文献   
33.
This paper describes experimental techniques with head-fixed, operantly conditioned rodents that allow the control of stimulus presentation and tracking of motor output at hitherto unprecedented levels of spatio-temporal precision. Experimental procedures for the surgery and behavioral training are presented. We place particular emphasis on potential pitfalls using these procedures in order to assist investigators who intend to engage in this type of experiment. We argue that head-fixed rodent models, by allowing the combination of methodologies from molecular manipulations, intracellular electrophysiology, and imaging to behavioral measurements, will be instrumental in combining insights into the functional neuronal organization at different levels of observation. Provided viable behavioral methods are implemented, model systems based on rodents will be complementary to current primate models--the latter providing highest comparability with the human brain, while the former offer hugely advanced methodologies on the lower levels of organization, for example, genetic alterations, intracellular electrophysiology, and imaging.  相似文献   
34.
The synthesis of fluorinated C-mannopeptides and their evaluation as E- and P-selectin inhibitors is described. These molecules are difluorinated analogues of CH2-glycopeptides already reported to act as sLex mimics. The α and β anomers of these CF2-glycopeptides have been prepared, as well as their 1-hydroxy analogues which were present in solution as an equilibrium mixture of α- and β-pyranose and α- and β-furanose forms. These molecules showed inhibitory activities comparable to their CH2 counterparts with a moderate influence of the pseudo-anomeric center configuration.  相似文献   
35.
Documentation of early human migrations through Island Southeast Asia and Wallacea en route to Australia has always been problematic due to a lack of well-dated human skeletal remains. The best known modern humans are from Niah Cave in Borneo (40-42 ka), and from Tabon Cave on the island of Palawan, southwest Philippines (47 ± 11 ka). The discovery of Homo floresiensis on the island of Flores in eastern Indonesia has also highlighted the possibilities of identifying new hominin species on islands in the region. Here, we report the discovery of a human third metatarsal from Callao Cave in northern Luzon. Direct dating of the specimen using U-series ablation has provided a minimum age estimate of 66.7 ± 1 ka, making it the oldest known human fossil in the Philippines. Its morphological features, as well as size and shape characteristics, indicate that the Callao metatarsal definitely belongs to the genus Homo. Morphometric analysis of the Callao metatarsal indicates that it has a gracile structure, close to that observed in other small-bodied Homo sapiens. Interestingly, the Callao metatarsal also falls within the morphological and size ranges of Homo habilis and H. floresiensis. Identifying whether the metatarsal represents the earliest record of H. sapiens so far recorded anywhere east of Wallace’s Line requires further archaeological research, but its presence on the isolated island of Luzon over 65,000 years ago further demonstrates the abilities of humans to make open ocean crossings in the Late Pleistocene.  相似文献   
36.
The RIT 4199 (H3N2) strain was obtained by recombination of PR/8/34 (H0N1) and A/Alaska/5/77 (H3N2) isolates. Its genetic composition was determined by RNA-RNA hybridization and by identification by gel electrophoresis of the double-standard RNA formed. The RIT 4199 was inoculated intranasally to 27 seronegative volunteers at a dose of 10(7.3)EID50. The results show that it is suitable for live vaccine strain.  相似文献   
37.
4-Benzylamino-(and 4-chloromethyl)-2-nitro-beta-D-glucuronides (4, 10) and their 2-substituted-4-nitro regioisomers (7, 13) were prepared by glycosidation of the 3-nitro-4-hydroxy- and the 2-hydroxy-5-nitro-benzylic alcohol, respectively, with a glucuronyl donor. Carbonate activation followed by reaction with benzylamine or methanesulfonyl chloride afforded, after complete deprotection, the target molecules 4, 7, 10 and 13. These compounds have been synthesized to determine whether these molecules are (or not) glucuronidase inhibitors. After incubation with bovine liver beta-glucuronidase, none of the cleavage products (the titled quinone-methides) showed to be irreversible inhibitors of this enzyme.  相似文献   
38.
A yearly global fire history is a prerequisite for quantifying the contribution of previous fires to the past and present global carbon budget. Vegetation fires can have both direct (combustion) and long‐term indirect effects on the carbon cycle. Every fire influences the ecosystem carbon budget for many years, as a consequence of internal reorganization, decomposition of dead biomass, and regrowth. We used a two‐step process to estimate these effects. First we synthesized the available data available for the 1980s or 1990s to produce a global fire map. For regions with no data, we developed estimates based on vegetation type and history. Second, we then worked backwards to reconstruct the fire history. This reconstruction was based on published data when available. Where it was not, we extrapolated from land use practices, qualitative reports and local studies, such as tree ring analysis. The resulting product is intended as a first approximation for questions about consequences of historical changes in fire for the global carbon budget. We estimate that an average of 608 Mha yr?1 burned (not including agricultural fires) at the end of the 20th century. 86% of this occurred in tropical savannas. Fires in forests with higher carbon stocks consumed 70.7 Mha yr?1 at the beginning of the century, mostly in the boreal and temperate forests of the Northern Hemisphere. This decreased to 15.2 Mha yr?1 in the 1960s as a consequence of fire suppression policies and the development of efficient fire fighting equipment. Since then, fires in temperate and boreal forests have decreased to 11.2 Mha yr?1. At the same time, burned areas increased exponentially in tropical forests, reaching 54 Mha yr?1 in the 1990s, reflecting the use of fire in deforestation for expansion of agriculture. There is some evidence for an increase in area burned in temperate and boreal forests in the closing years of the 20th century.  相似文献   
39.
40.
Protected areas (PAs) are pivotal tools for biodiversity conservation on the Earth. Europe has had an extensive protection system since Natura 2000 areas were created in parallel with traditional parks and reserves. However, the extent to which this system covers not only taxonomic diversity but also other biodiversity facets, such as evolutionary history and functional diversity, has never been evaluated. Using high-resolution distribution data of all European tetrapods together with dated molecular phylogenies and detailed trait information, we first tested whether the existing European protection system effectively covers all species and in particular, those with the highest evolutionary or functional distinctiveness. We then tested the ability of PAs to protect the entire tetrapod phylogenetic and functional trees of life by mapping species'' target achievements along the internal branches of these two trees. We found that the current system is adequately representative in terms of the evolutionary history of amphibians while it fails for the rest. However, the most functionally distinct species were better represented than they would be under random conservation efforts. These results imply better protection of the tetrapod functional tree of life, which could help to ensure long-term functioning of the ecosystem, potentially at the expense of conserving evolutionary history.  相似文献   
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