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131.
Tuber magnatum Pico, the delectable white truffle, is the most prized truffle species. In this study, we examined the reddish pigmentation that frequently occurs in T. magnatum ascomata for the presence of pigment-producing bacteria.The inner part of the reddish-pigmented region of three T. magnatum ascomata collected in North–Central Italy was analysed. This reddish part was used to establish a bacterial culture collection and to extract the total genomic DNA in order to obtain a library of 16S rRNA genes representative of the bacterial community. The molecular approach revealed limited microbial diversity within the reddish-pigmented regions compared to the wider range of bacterial species commonly found at the same maturation stage and season in T. magnatum ascomata. The pigmented regions showed a prevalence of specific bacterial species belonging to α-, β- and γ- Proteobacteria, Actinobacteria and Firmicutes. From the tandem mass spectrometry analysis of the extracted pigment, four compounds were identified: i) bixin, ii) β-carotene, iii) cis-1-glycosyl-apo-8′- lycopene and iv) the fucoxanthin. Carotenoid producing species such as Microbacterium and Chryseobacterium emerged as the most likely cause of the peculiar reddish pigment production. Indeed, our findings suggest that the peculiar reddish pigment might be produced by these bacterial species.  相似文献   
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Janus kinases (JAKs) play a pleiotropic role in several important physiological processes, such as cell maturation, cell proliferation, and cell death, via providing transmission signals from several molecules, such as cytokines, interferons, hormones, and growth factors, to the nucleus. Bone physiology and remodeling are markedly influenced by proinflammatory cytokines. Among them, interleukin-1 (IL-1) and IL-6 are considered potent stimulator of bone resorption. Several cytokine receptors, such as IL-6 receptors, are characterized by tyrosine kinases of the JAK family associated with their intracellular domains. There is an emerging interest in the effects of JAKs inhibition on the cells involved in bone remodeling. JAK inhibitors represent a new class of molecules involved in the therapy of numerous immune-mediated inflammatory diseases. In this review, we want to focus on the role of JAKs inhibitors on bone remodeling and on RANKL-RANK-OPG signal and inflammatory cytokines which are involved in the regulation of bone cells, such as osteoblasts and osteoclasts.  相似文献   
134.
Cycling stage races are strenuous endurance events during which exercise-induced variations in hematological parameters are consistently observed. However, specific literature on such changes is scarce and published data have been derived from small samples of athletes. The aims of this study were: (1) to determine the hematological response to middle-term strenuous endurance; and (2) to determine whether a relationship exists between the athlete-specific hematological profile and final placement in a cycling stage race. The study population was male professional cyclists (n = 253) competing in the 2010 (n = 144) and 2012 (n = 109) GiroBio 10-day stage races. Blood draws taken before the start of the race, at mid-race, and at end-race were performed in strict compliance with academic and anti-doping pre-analytical warnings. Blood chemistry included white blood cell, red blood cell, hemoglobin concentration, hematocrit, mean corpuscular volume (MCV), mean hemoglobin content (MCH), mean corpuscular hemoglobin content (MCHC), platelets, and reticulocyte relative and absolute counts. Compared to baseline values, erythrocyte, hemoglobin, hematocrit, MCHC, platelet and reticulocyte counts were all consistently lower at mid-race, but returned to normal by race-end, while leukocytes were increased in the final phase. MCV increased during both events. MCH increased in the first part to then return to baseline in the 2012 race. The calculated OFF-score consistently decreased in the first half of the race before increasing, but remained lower than the baseline value. The trends of variation in hematological parameters were substantially similar in both events. There was an inverse, albeit weak, relationship between placement and erythrocyte, platelet, hemoglobin, hematocrit and OFF-score values in the 2010, but not in the 2012 race. In conclusion, the data confirm that, in this large series of elite road cyclists, the strenuous effort a rider sustains during a stage race induces appreciable changes in the hematological profile.  相似文献   
135.
Most of the ambient dissolved organic carbon (DOC) is refractory to microbial degradation; bacteria can consume a minor but variable part of the DOC pool over periods of hours and days. It is important to increase our knowledge of the dynamics of the biodegradable fraction of DOC (BDOC) to understand the global carbon budget.Several methods for determining BDOC have been developed; however, the problem of most of them is the time (days/weeks) required for the colonization and/or determination.In this paper, we describe the application to seawater of a plug-flow bioreactor to measure BDOC within 3–4 h. The bioreactor was built following Søndergaard and Worm [Søndergaard, M., Worm, J., 2001. Measurement of biodegradable dissolved organic carbon (BDOC) in lake water with a bioreactor. Water Res. 35, 2505-2513.] protocols for the measurement of BDOC in lake water. We analyzed BDOC on samples collected in the Gulf of Trieste during autumn–winter and summer 2003–2004. BDOC concentrations varied from 8 to 24 μM and represented from 10.3% to 25.5% of the total DOC. To evaluate the effectiveness of this method, we compared bioreactor BDOC measurement with data obtained from batch cultures. The results indicate that BDOC in coastal seawater can be measured rapidly and reliably with this bioreactor.  相似文献   
136.
The impacts of wind energy on bat populations is a growing concern because wind turbine blades can strike and kill bats, and wind turbine development is increasing. We tested the effectiveness of 2 management actions at 2 wind-energy facilities for reducing bat fatalities: curtailing turbine operation when wind speeds were <5.0 m/second and combining curtailment with an acoustic bat deterrent developed by NRG Systems. We measured the effectiveness of the management actions using differences in counts of bat carcasses quantified by daily and twice-per-week standardized carcass searches of cleared plots below turbines, and field trials that estimated searcher efficiency and carcass persistence. We studied turbines located at 2 adjacent wind-energy facilities in northeast Illinois, USA, during fall migration (1 Aug–15 Oct) in 2018. We estimated the effectiveness of each management action using a generalized linear mixed-effects model with several covariates. Curtailment alone reduced overall bat mortality by 42.5% but did not reduce silver-haired bat (Lasionycteris noctivagans) mortality. Overall bat fatality rates were 66.9% lower at curtailed turbines with acoustic deterrents compared to turbines that operated at manufacturer cut-in speed. Curtailment and the deterrent reduced bat mortality to varying degrees between species, ranging from 58.1% for eastern red bats (Lasiurus borealis) to 94.4 for big brown bats (Eptesicus fuscus). Hoary (Lasiurus cinereus) and silver-haired bat mortality was reduced by 71.4% and 71.6%, respectively. Our study lacked a deterrent-only treatment group because of the expense of acoustic deterrents. We estimated the additional reduction in mortality with concurrent deployment of the acoustic deterrent and curtailment under the assumption that curtailment and the acoustic deterrent would have reduced mortality by the same percentage at adjacent wind-energy facilities. Acoustic deterrents resulted in 31.6%, 17.4%, and 66.7% additional reductions of bat mortality compared to curtailment alone for eastern red bat, hoary bat, and silver-haired bat, respectively. The effectiveness of acoustic deterrents for reducing bat mortality at turbines with rotor-swept area diameters >110 m is unknown because high frequency sound attenuates quickly, which reduces coverage of rotor-swept areas. Management actions should consider species differences in the ability of curtailment and deterrents to reduce bat mortality and increase energy production.  相似文献   
137.
Obestatin and its derivative Ob(11-23) are recently discovered peptides produced in the rat stomach. They have proven to be involved in the regulation of energy balance, inhibiting feeding, causing reductions in food intake, body weight and jejunal contraction in rodents. The G-protein coupled receptor, GPR39, was originally proposed as being an obestatin target receptor, but this remains controversial. As such, the molecular mechanism for obestatin's effects in vivo is still uncertain. Here we report the CD and NMR conformational analysis of obestatin and Ob(11-23). Both peptides assume a regular secondary structure in the C-terminal region of the molecule. In this region, structural elements similar to other GPCR binding neuropeptides support the identity of obestatin as a new and functionally autonomous GPCR ligand. Conversely sequence and conformational specificity point to a new farmacoforic structure, on which innovative derivatives with a potential role in the treatment of obesity can be designed and synthetized.  相似文献   
138.
Starting from (R)‐6,6′‐dimethyldiphenyl‐2,2′‐dicarboxylic acid, a novel class of enantiomerically pure cyclic dialkyl phosphates was synthesized and properly characterized. The absolute configuration was determined by 2D NOESY experiments. The catalytic behavior of the new chiral Bronsted acids was investigated in the stereoselective addition of a silyl keteneacetal to aldimines. The Mannich‐type reaction was promoted in up to 94% yields and enantioselectivities up to 55%. On the basis of preliminary molecular mechanic calculations, a model of stereoselection was also proposed to explain the sense of the enantioselectivity observed in the reaction. Chirality 2010. © 2009 Wiley‐Liss, Inc.  相似文献   
139.
Muscat flavor is a relevant trait both in winemaking and in fresh grape consumption. From a chemical point of view, it is strongly related to the accumulation of monoterpenes in berries. However, knowledge of the genetic mechanisms underlying its regulation is still limited. The objective of this study was to dissect the genetic determinism of aroma in grapevine by applying the analysis of quantitative trait loci (QTL) and the candidate gene (CG) approach. Two F1 segregating progenies were evaluated through high-resolution gas chromatography–mass spectrometry (HRGC–MS) for the amounts of individual monoterpenes over 3 and 2 years. In the Italia × Big Perlon cross 34 CGs, chosen according to gene ontology (GO) terms, were placed on a complete map and tested for linkage with QTLs for linalool, nerol and geraniol levels. Two CGs mapped within a QTL for linalool content on LG 10. A third one co-localized with a major QTL for the level of the three monoterpenes on LG 5; this gene encodes 1-deoxy-d-xylulose 5-phosphate synthase (DXS), which is the first enzyme in the plastidial pathway of terpene biosynthesis. Depending on these findings, we report the first in silico analysis of grapevine DXS genes based on the whole genome sequence. Further research on the functional significance of these associations might help to understand the genetic control of Muscat flavor. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users. J. Battilana and L. Costantini equally contributed to the work.  相似文献   
140.
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