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1.
M. Gaudet F. Villani M. Cherubini I. Beritognolo I. Dalla Ragione S. Proietti 《Plant biosystems》2019,153(4):491-497
In central Italy, Prunus cerasus var. austera is cultivated as small stands or scattered trees in marginal areas for the production of jam and wine. Thanks to the healthy attributes of its products and its ability to grow in different environmental conditions, this variety has gained new interest in the development of marginal areas. We assessed the level of the genetic variability of P. cerasus var. austera germplasm from central Italy and identified a ‘core collection’ representative of the present genetic diversity. A total of 161 trees, morphologically identified as var. austera, and one tree, identified as var. caproniana were collected and genotyped by 14 SSRs. Two individuals provided by a commercial plant nursery, one of P. cerasus var. caproniana and one of P. cerasus var. austera, were used as control. Thirteen SSRs presented private alleles in austera. Seven individuals morphologically identified as austera revealed private alleles specific to caproniana. The PCoA and Bayesian clustering analysis showed a main genetic group including var. austera, while a second group included all the caproniana-like genotypes. A core collection of 31 trees (46% of austera genotypes) was selected. This study can be considered as a starting point for future investigations on this variety. 相似文献
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Research conducted by Rumbaugh, Savage-Rumbaugh, and Hegel (1987) demonstrated that chimpanzees, presented with two pairs of quantities of chocolate chips, were capable of combining noncontiguous areas in order to choose the pair that contained the greater quantity. Further research (Rumbaugh, Savage-Rumbaugh, and Pate, 1988) showed that this ability is not based on the avoidance of the pair containing the smallest single amount or selection of the pair containing the largest single amount. In the experiments in the present sutdy, the influence of wells containing zero or one chocolate on summation and the consequences of eliminating the requirement to sum noncontiguous areas by interpersing trials in which only two (rather than four) food wells were investigated. It was found that summation of quantities occurred regardless whether food wells containing zero or one were present. Also, the chimpanzees performed significantly better on two-well trials than on four-well trials, thereby suggesting that they were not simply discounting the space between the wells on four-well trials but, instead, were employing a combinatorial process which we call summation. 相似文献
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Cody Raul Cardenas Andrew J. Mularo Andreas S. Chavez Rachelle M. M. Adams 《Biotropica》2023,55(1):145-159
The coevolutionary relationship between fungus-growing ants (Formicidae: Attini: Attina) and their symbionts has been well studied in the Panamanian rain forests. To further understand the ecological context of these evolutionary relationships, we have examined the population-genetic structure of the fungus-growing ant species Mycetomoellerius mikromelanos Cardenas, Schultz, Adams 2021 in the Panama Canal Zone. We specifically investigated the presence of population structure, the significance of geographic features (i.e., creeks) limiting gene flow, and relatedness between ant colonies. To accomplish this, we genotyped 85 ant colonies from nine creeks across an approximately 30 km transect in Parque National Soberanía, Panama, using double-digest restriction-site-associated DNA sequencing. We did not find distinct population structure using two genetic clustering methods; however, we did detect an effect of isolation by distance. Furthermore, related colonies were frequently detected on the same creek or neighboring creeks, and some at further geographic distances. Collectively, these findings demonstrate that new colonies tend to establish on natal creeks and occasionally on distant creeks following long-distance dispersal events. We discuss how population-genetic patterns reveal the natural history of M. mikromelanos in Parque National Soberanía and how these results fit into the context of fungus-growing ant mutualisms. Abstract in Spanish is available with online material. 相似文献
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Abstract— Cortical monoamine changes during ischemic episodes of varied duration and their sequence of changes following cerebral reperfusion were studied in the gerbil. Forty-one percent of 280 animals exhibited signs of cerebral hemispheric ischemia (stroke) after unilateral common carotid artery occlusion. Norepinephrine (NE) levels decreased after 60 min in the occluded hemisphere of stroked animals but dopamine (DA) levels were unaltered. S-Hydroxytryptamine (5-HT) levels became bilaterally reduced in both stroked and non-stroked animals as soon as S min after occlusion. Upon reperfusion after periods of 30 or 60 min of occlusion there was a bilateral rebound increase of cortical NE and DA levels to well above control values in stroked and non-stroked animals. 5-HT levels remained reduced in both groups. Results suggest disorder of monoamine metabolism in ischemic brain which persists during the early reperfusion period, perhaps contributing to deficits in neurological function. Monoamine changes in contralateral non-ischemic hemispheres both during the occlusion and reperfusion periods are thought further evidence of diaschisis. 相似文献
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Staphylococcus aureus protease has been spin-labelled at the active-site serine residue with the monocyclic-phosphorus spin label (MSL), 1-oxyl-2,2,6,6-tetramethyl-4-peperi-dinylethylphosphorofluoridate. The electron paramagnetic resonance (E.P.R.) sbectra of the protease in different buffers at various pH's have been analyzed and compared with those of trypsin, subtilisin BPN', and alpha-chymotrypsin under identical conditions. In a given buffer, the shape of E.P.R. signals of spin-labelled staphylococcal protease is unaffected by pH changes except below pH 4.0, at which a gradual loss of conformational integrity of the active site occurs. In bicarbonate buffer and particularly in acetate buffer, the mobility of the label is much more restricted than in phosphate buffer or in potassium chloride solution. The implications of this finding are discussed in terms of a model whereby the label is able to orient towards two different but adjacent regions of the active site. The relative population of the label in each of these orientations is believed to be buffer-dependent. An attempt to correlate the shape of the te.p.r. signals with the pH values of maximal proteolytic avtivity of the enzyme is also presented. These results show that to obtain meaningful information from a comparative spin label study of the geometry of the active site of serine proteases, particular care should be exercised to assure that the different proteases experience identical conditions of pH, buffer, and temperature. 相似文献
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Simon D. French Joanne E. McKenzie Denise A. O'Connor Jeremy M. Grimshaw Duncan Mortimer Jill J. Francis Susan Michie Neil Spike Peter Schattner Peter Kent Rachelle Buchbinder Matthew J. Page Sally E. Green 《PloS one》2013,8(6)
Introduction
This cluster randomised trial evaluated an intervention to decrease x-ray referrals and increase giving advice to stay active for people with acute low back pain (LBP) in general practice.Methods
General practices were randomised to either access to a guideline for acute LBP (control) or facilitated interactive workshops (intervention). We measured behavioural predictors (e.g. knowledge, attitudes and intentions) and fear avoidance beliefs. We were unable to recruit sufficient patients to measure our original primary outcomes so we introduced other outcomes measured at the general practitioner (GP) level: behavioural simulation (clinical decision about vignettes) and rates of x-ray and CT-scan (medical administrative data). All those not involved in the delivery of the intervention were blinded to allocation.Results
47 practices (53 GPs) were randomised to the control and 45 practices (59 GPs) to the intervention. The number of GPs available for analysis at 12 months varied by outcome due to missing confounder information; a minimum of 38 GPs were available from the intervention group, and a minimum of 40 GPs from the control group. For the behavioural constructs, although effect estimates were small, the intervention group GPs had greater intention of practising consistent with the guideline for the clinical behaviour of x-ray referral. For behavioural simulation, intervention group GPs were more likely to adhere to guideline recommendations about x-ray (OR 1.76, 95%CI 1.01, 3.05) and more likely to give advice to stay active (OR 4.49, 95%CI 1.90 to 10.60). Imaging referral was not statistically significantly different between groups and the potential importance of effects was unclear; rate ratio 0.87 (95%CI 0.68, 1.10) for x-ray or CT-scan.Conclusions
The intervention led to small changes in GP intention to practice in a manner that is consistent with an evidence-based guideline, but it did not result in statistically significant changes in actual behaviour.Trial Registration
Australian New Zealand Clinical Trials Registry ACTRN012606000098538 相似文献10.
Stephanie-May Ruchat Andrée-Anne Houde Grégory Voisin Julie St-Pierre Patrice Perron Jean-Patrice Baillargeon Daniel Gaudet Marie-France Hivert Diane Brisson Luigi Bouchard 《Epigenetics》2013,8(9):935-943
Offspring exposed to gestational diabetes mellitus (GDM) have an increased risk for chronic diseases, and one promising mechanism for fetal metabolic programming is epigenetics. Therefore, we postulated that GDM exposure impacts the offspring’s methylome and used an epigenomic approach to explore this hypothesis. Placenta and cord blood samples were obtained from 44 newborns, including 30 exposed to GDM. Women were recruited at first trimester of pregnancy and followed until delivery. GDM was assessed after a 75-g oral glucose tolerance test at 24–28 weeks of pregnancy. DNA methylation was measured at > 485,000 CpG sites (Infinium HumanMethylation450 BeadChips). Ingenuity Pathway Analysis was conducted to identify metabolic pathways epigenetically affected by GDM. Our results showed that 3,271 and 3,758 genes in placenta and cord blood, respectively, were potentially differentially methylated between samples exposed or not to GDM (p-values down to 1 × 10−06; none reached the genome-wide significance levels), with more than 25% (n = 1,029) being common to both tissues. Mean DNA methylation differences between groups were 5.7 ± 3.2% and 3.4 ± 1.9% for placenta and cord blood, respectively. These genes were likely involved in the metabolic diseases pathway (up to 115 genes (11%), p-values for pathways = 1.9 × 10−13 < p < 4.0 × 10−03; including diabetes mellitus p = 4.3 × 10−11). Among the differentially methylated genes, 326 in placenta and 117 in cord blood were also associated with newborn weight. Our results therefore suggest that GDM has epigenetic effects on genes preferentially involved in the metabolic diseases pathway, with consequences on fetal growth and development, and provide supportive evidence that DNA methylation is involved in fetal metabolic programming. 相似文献