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981.
It is generally assumed that steroid hormones are carried in the blood free and/or bound to plasma proteins. We investigated whether blood cells were also able to bind/carry sex-related hormones: estrone, estradiol, DHEA and testosterone. Wistar male and female rats were fed a cafeteria diet for 30 days, which induced overweight. The rats were fed the standard rat diet for 15 additional days to minimize the immediate effects of excess ingested energy. Controls were always kept on standard diet. After the rats were killed, their blood was used for 1) measuring plasma hormone levels, 2) determining the binding of labeled hormones to washed red blood cells (RBC), 3) incubating whole blood with labeled hormones and determining the distribution of label between plasma and packed cells, discounting the trapped plasma volume, 4) determining free plasma hormone using labeled hormones, both through membrane ultrafiltration and dextran-charcoal removal. The results were computed individually for each rat. Cells retained up to 32% estrone, and down to 10% of testosterone, with marked differences due to sex and diet (the latter only for estrogens, not for DHEA and testosterone). Sex and diet also affected the concentrations of all hormones, with no significant diet effects for estradiol and DHEA, but with considerable interaction between both factors. Binding to RBC was non-specific for all hormones. Estrogen distribution in plasma compartments was affected by sex and diet. In conclusion: a) there is a large non-specific RBC-carried compartment for estrone, estradiol, DHEA and testosterone deeply affected by sex; b) Prior exposure to a cafeteria (hyperlipidic) diet induced hormone distribution changes, affected by sex, which hint at sex-related structural differences in RBC membranes; c) We postulate that the RBC compartment may contribute to maintain free (i.e., fully active) sex hormone levels in a way similar to plasma proteins non-specific binding. 相似文献
982.
983.
Transcranial magnetic theta burst stimulation (TBS) differs from other high-frequency rTMS protocols because it induces plastic changes up to an hour despite lower stimulus intensity and shorter duration of stimulation. However, the effects of TBS on neuronal oscillations remain unclear. In this study, we used electroencephalography (EEG) to investigate changes of neuronal oscillations after continuous TBS (cTBS), the protocol that emulates long-term depression (LTD) form of synaptic plasticity. We randomly divided 26 healthy humans into two groups receiving either Active or Sham cTBS as control over the left primary motor cortex (M1). Post-cTBS aftereffects were assessed with behavioural measurements at rest using motor evoked potentials (MEPs) and at active state during the execution of a choice reaction time (RT) task in combination with continuous electrophysiological recordings. The cTBS-induced EEG oscillations were assessed using event-related power (ERPow), which reflected regional oscillatory activity of neural assemblies of θ (4-7.5 Hz), low α (8-9.5 Hz), μ (10-12.5 Hz), low β (13-19.5 Hz), and high β (20-30 Hz) brain rhythms. Results revealed 20-min suppression of MEPs and at least 30-min increase of ERPow modulation, suggesting that besides MEPs, EEG has the potential to provide an accurate cortical readout to assess cortical excitability and to investigate the interference of cortical oscillations in the human brain post-cTBS. We also observed a predominant modulation of β frequency band, supporting the hypothesis that cTBS acts more on cortical level. Theta oscillations were also modulated during rest implying the involvement of independent cortical theta generators over the motor network post cTBS. This work provided more insights into the underlying mechanisms of cTBS, providing a possible link between synchronised neural oscillations and LTD in humans. 相似文献
984.
985.
A high-density consensus map of A and B wheat genomes 总被引:1,自引:0,他引:1
Daniela Marone Giovanni Laidò Agata Gadaleta Pasqualina Colasuonno Donatella B. M. Ficco Angelica Giancaspro Stefania Giove Giosué Panio Maria A. Russo Pasquale De Vita Luigi Cattivelli Roberto Papa Antonio Blanco Anna M. Mastrangelo 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2012,125(8):1619-1638
A durum wheat consensus linkage map was developed by combining segregation data from six mapping populations. All of the crosses were derived from durum wheat cultivars, except for one accession of T. ssp. dicoccoides. The consensus map was composed of 1,898 loci arranged into 27 linkage groups covering all 14 chromosomes. The length of the integrated map and the average marker distance were 3,058.6 and 1.6?cM, respectively. The order of the loci was generally in agreement with respect to the individual maps and with previously published maps. When the consensus map was aligned to the deletion bin map, 493 markers were assigned to specific bins. Segregation distortion was found across many durum wheat chromosomes, with a higher frequency for the B genome. This high-density consensus map allowed the scanning of the genome for chromosomal rearrangements occurring during the wheat evolution. Translocations and inversions that were already known in literature were confirmed, and new putative rearrangements are proposed. The consensus map herein described provides a more complete coverage of the durum wheat genome compared with previously developed maps. It also represents a step forward in durum wheat genomics and an essential tool for further research and studies on evolution of the wheat genome. 相似文献
986.
Luis Miguel Pardo Carlos Simón Cardyn José Garcés-Vargas 《Helgoland Marine Research》2012,66(3):253-263
Settlement of benthic marine invertebrates is determined by the interaction between physical factors and biological processes, in which the tide, wind, and predation can play key roles, especially for species that recruit within estuaries. This complexity promotes high variability in recruitment and limited predictability of the size of annual cohorts. This study describes the settlement patterns of megalopae of the commercially important crab Cancer edwardsii at three locations (one in the center and two at the mouth of the estuary) within the Valdivia River estuary (~39.9°S), over three consecutive years (2006–2008). At each location, 12 passive benthic collectors with a natural substratum were deployed for 48?h at 7-day intervals, over a lunar cycle. Half of the collectors were covered with mesh to exclude predators. The main findings were as follows: (1) circulation changes due to upwelling relaxation or onshore winds controlled crab settlement at sites within the mouth of the estuary, (2) at the internal estuarine site, settlement was dominated by tidal effects, and (3) the effect of predation on settlement was negligible at all scales. The results show that the predominant physical factor controlling the return of competent crab larvae to estuarine environments varies spatially within the estuary. The lack of tidal influence on settlement at the mouth of the estuary can be explained by the overwhelming influence of the intense upwelling fronts and the micro-tidal regime in the study area. 相似文献
987.
Antonio Pisani Massimo Imbriaco Carmela Zizzo Giuseppe Albeggiani Paolo Colomba Riccardo Alessandro Francesco Iemolo Giovanni Duro 《BMC cardiovascular disorders》2012,12(1):1-4
Background
Infective Endocarditis (IE) is considered as a multifaceted problem in every aspect from etiology and presentation to diagnosis and management. Early recognition of this disease and especially its complications, remain a critical task for the cardiologist. Atrial endocarditis is a rare and sometimes unrecognized complication of mitral valve endocarditis.Case presentation
We present a 48 year-old male patient who was admitted to our clinic because of recent onset of malaise, fever, jaundice and peripheral edema. Important physical findings were peripheral stigmata of IE in addition to holosystolic murmur over the left sternal border. Transthoracic and transesophageal echocardiophy revealed a severe eccentric MR due to a flailed posterior mitral valve caused by IE. The presence of atrial septal endocarditis caused by jet streaming was also observed. Blood culture was positive for streptococcus oralis and antibiotic therapy was immediately initiated. Considering the large burden of infective tissue, the patient was planned for an early surgical intervention. A minimally invasive resection of the atrial mass, direct closure of the defect, resection of the diseased portions of mitral leaflets and implantation of a biological mitral valve prosthesis was performed. Intra-operative and histological findings confirmed provisional diagnosis by echocardiography.Conclusions
Together with comprehensive echocardiographic evaluation, attention should be placed on mural vegetations and excluded among all cases of mitral valve endocarditis, particularly those with severe eccentric regurgitant jets. 相似文献988.
The Top 10 fungal pathogens in molecular plant pathology 总被引:18,自引:0,他引:18
Dean R Van Kan JA Pretorius ZA Hammond-Kosack KE Di Pietro A Spanu PD Rudd JJ Dickman M Kahmann R Ellis J Foster GD 《Molecular Plant Pathology》2012,13(4):414-430
The aim of this review was to survey all fungal pathologists with an association with the journal Molecular Plant Pathology and ask them to nominate which fungal pathogens they would place in a 'Top 10' based on scientific/economic importance. The survey generated 495 votes from the international community, and resulted in the generation of a Top 10 fungal plant pathogen list for Molecular Plant Pathology. The Top 10 list includes, in rank order, (1) Magnaporthe oryzae; (2) Botrytis cinerea; (3) Puccinia spp.; (4) Fusarium graminearum; (5) Fusarium oxysporum; (6) Blumeria graminis; (7) Mycosphaerella graminicola; (8) Colletotrichum spp.; (9) Ustilago maydis; (10) Melampsora lini, with honourable mentions for fungi just missing out on the Top 10, including Phakopsora pachyrhizi and Rhizoctonia solani. This article presents a short resumé of each fungus in the Top 10 list and its importance, with the intent of initiating discussion and debate amongst the plant mycology community, as well as laying down a bench-mark. It will be interesting to see in future years how perceptions change and what fungi will comprise any future Top 10. 相似文献
989.