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Desmosterol, the main sterol in rabbit semen： distribution among semen subfractions and its role in the in vitro spermatozoa acrosome reaction and motility

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Asian Journal of Andrology 2010年第6期12卷 862-870页

作者： Evangelia Mourvaki Raffaella Cardinali Rita Roberti alessandro Dal bosco Cesare Castellini Department of Applied Biology Section of Animal Science University of Perugia Perugia 06100 Italy Department of Internal Medicine Section of Biochemistry University of Perugia Perugia 06122 Italy

Sterols are essential components of the cell membrane lipid bilayer that include molecules such as cholesterol and desmosterol, which are significantly found in the spermatozoa of several animal species. However, the presence of desmosterol in rabbit semen has never been investigated. The aims of this study were to characterize the sterol composition of subfractions of ejaculated rabbit semen and evaluate the in vitro effects of sterol on the spermatozoa acrosome reaction and motility. Two sterols, occurring prevalently in the free form （94.3%）, were identified in whole semen collected from 10 fertile New Zealand White rabbits, specifically desmosterol （58.5% of total sterols） and cholesterol （35.9% of total sterols）. Desmosterol was the predominant sterol found in all subfractions of rabbit semen, varying from 56.7% （in the prostatic secretory granules, PSGs） to 63.8% （in the seminal plasma）. Spermatozoa contained an intermediate proportion of desmosterol （59.8%）, which was asymmetrically distributed between the heads （52.0% of the total content of sterols） and the tails （81.8%）. Results showed that both desmosterol and cholesterol can be transferred from the PSGs to the spermatozoa and are equally effective in inhibiting in vitro spermatozoa capacitation at a concentration higher than 1 mg L^-1. In contrast, neither desmosterol nor cholesterol had a significant effect on spermatozoa motility. Thus, it was concluded that, the various fractions of rabbit seminal fluid differ from each other in sterol composition and quantity, probably due to their different functional properties, and these fractions may undergo significant sterol changes depending on the stage of spermatozoa capacitation.

关键词： acrosome reaction cholesterol desmosterol motility prostatic secretory granules rabbit seminal plasma spermatozoa head spermatozoa tail

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Exercise interventions for older adults: A systematic review of meta-analyses

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Journal of Sport and Health Science 2021年第1期10卷 29-47,I0001页

作者： Claudio Di Lorito Annabelle Long Adrian Byrne Rowan H.Harwood John R.F.Gladman Stefan Schneider Pip Logan alessandro bosco Veronika van der Wardt Division of Rehabilitation Ageingand WellbeingSchool of MedicineUniversity of NottinghamNottingham NG72UHUK Division of Health Sciences School of MedicineUniversity of NottinghamNottingham NG72UHUK Institute of Movement and Neurosciences German Sport UniversityCologne 50933Germany Division of Psychiatry and Applied Psychology School of MedicineUniversity of NottinghamNottingham NG72UHUK Center for Methodology and Health Research Department of General MedicinePreventive and Rehabilitative MedicinePhilipps-Universität MarburgMarburg 35032Germany

Background:The evidence concerning which physical exercise characteristics are most effective for older adults is *** aimed to characterize the extent of this diversity and inconsistency and identify future directions for research by undertaking a systematic review of metaanalyses of exercise interventions in older ***:We searched the Cochrane Database of Systematic Reviews,PsycInfo,MEDLINE,Embase,CINAHL,AMED,SPORTDiscus,and Web of Science for articles that met the following criteria:(1)meta-analyses that synthesized measures of improvement(e.g.,effect sizes)on any outcome identified in studies of exercise interventions;(2)participants in the studies meta-analyzed were adults aged 65+or had a mean age of 70+;(3)meta-analyses that included studies of any type of exercise,including its duration,frequency,intensity,and mode of delivery;(4)interventions that included multiple components(e.g.,exercise and cognitive stimulation),with effect sizes that were computed separately for the exercise component;and(5)meta-analyses that were published in any year or *** characteristics of the reviews,of the interventions,and of the parameters improved through exercise were reported through narrative *** of the interventions linked to the largest improvements was carried out by identifying the highest values for improvement recorded across the *** study included 56 meta-analyses that were heterogeneous in relation to population,sample size,settings,outcomes,and intervention ***:The largest effect sizes for improvement were found for resistance training,meditative movement interventions,and exercise-based active ***:The review identified important gaps in research,including a lack of studies investigating the benefits of group interventions,the characteristics of professionals delivering the interventions associated with better outcomes,and the impact of motivational strategies and of sig

关键词： Intervention Meta-analyses Old Physical exercise Systematic review

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A network of sex and competition： The promiscuous mating system of an invasive weevil

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Current Zoology 2015年第1期61卷 85-97页

作者： Alberto Francesco INGHILESI Giuseppe MAZZA Rita CERVO alessandro CINI Department of Biology University of Florence Via Romana 17 50125 Florence Italy Agricultural Research Council Research Centre for Agrobiology and Pedology via Lanciola 12/A Cascine del Riccio 50125 Florence Italy Department of Biology University of Florence Via Madonna del Piano 6 50019 Sesto Fiorentino Florence Italy Corpo Forestale dello Stato Centro Nazionale Biodiversit~t Forestale "Bosco Fontana"Via C. Ederle 16/a 37100 Verona Italy

Invasive alien pest insect species represent a major threat for agriculture and biodiversity. Because chemical treatments employed to contrast such pests elicit serious environmental and human health problems, a great effort is currently directed to develop long term and environmentally friendly biological control strategies. However, the successful application of some promising techniques, such as the Sterile Insect Technique （SIT）, requires a deep knowledge of the pest basic biology. Here, we argue that understanding pest sexual biology using a social network approach can significantly improve the performance of con- trol strategies. For example, SIT may benefit from understanding how individuals interact and how males accede to reproduction, in order to target the most reproductively active and polygamic males. In this paper we studied the socio-sexual networks of the Asian red palm weevil （RPW） Rhynchophorusferrugineus, a worldwide invader which is causing heavy economic impacts on several palm species. We found that the RPW has a highly promiscuous mating system, characterized by forced interruptions of pair copulations by additional males. The social network is highly non-random nor regular： few males almost monopolize repro- duction, behaving as key-players in the network of matings. Additionally, males have a stable pattern of sexual behaviour over time. We use RPW social network as a case study to direct the development of management techniques such as SIT strategy [Current Zoology 61 （1）： 85-97, 2015].

关键词： Social network analysis Pest management Mating system Reproductive skew Alien pest Rhynchophorusferrugineus

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