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Massimo Di Giulio 《Journal of molecular evolution》1989,29(4):288-293
Summary The level reached by the optimization of the polarity distances during the evolution of the genetic code was investigated. The results, although not conclusive, indicate that this optimization level is higher than the data reported in the literature. The results seem compatible with the reaching of an evolutionary minimum, with respect to the optimization of the polarity distances, by the genetic code during its formation. 相似文献
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Bäckesjö CM Vargas L Superti-Furga G Smith CI 《Biochemical and biophysical research communications》2002,299(3):510-515
Bruton's tyrosine kinase (Btk) is necessary for B-lymphocyte development. Mutation in the gene coding for Btk causes X-linked agammaglobulinemia (XLA) in humans. Similar to Btk, c-Abl is a tyrosine kinase shuttling between the cytoplasm and the nucleus where it is involved in different functions depending on the localization. In this report we describe for the first time that c-Abl and Btk physically interact and that c-Abl can phosphorylate tyrosine 223 in the SH3 domain of Btk. Interestingly, the Btk sequence matched a v-Abl substrate [correction] identified from a randomized peptide library and was also highly related to a number of previously found c-Abl substrates. 相似文献
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Fabio Palumbo Giulio Galla Nicola Vitulo Gianni Barcaccia 《Molecular breeding : new strategies in plant improvement》2018,38(10):122
The development of F1 hybrid varieties benefits from the synergistic effect of conventional and molecular marker-assisted breeding schemes. A sequencing run was carried out in Foeniculum vulgare (2n?=?2x?=?22) to develop the first genome draft and to identify microsatellites suitable for implementing multilocus SSR marker assays. A preliminary cytometric analysis allowed us to estimate the genome size (2C?=?2.64–2.86 pg), equal to about 1.34 Mbp for 1C genome, and to calculate the sequencing coverage (53×). The genome draft assembly into 300,408 scaffolds and its bioinformatic analysis enabled the annotation of coding and non-coding regions across the genome, including 103,306 SSR elements. A total of 100 microsatellites were randomly chosen among those with dinucleotide and trinucleotide repeat motifs and with a repeat motif length?≥?25 times and were preliminarily tested. Of these, 27 SSR markers, classified as suitable for genetic diversity analyses, were efficiently organized in five PCR multiplex assays and validated using a core collection of 100 fennel individuals potentially useful for the development of inbred lines and F1 hybrids. All SSR loci were found to be polymorphic, scoring an observed number of marker alleles Na?=?207 and an average polymorphism information content PIC?=?0.69. The SSR data were used to calculate (i) the degree of homozygosity for the individual inbred lines (0.35?<?Ho?<?0.96), to eventually plan additional selfing or sibling cycles, and (ii) the degree of genetic similarity for all possible pair-wise comparisons between parental inbred lines (GS?=?0.55–0.77), to identify the most divergent combinations for the constitution of experimental F1 hybrids. The integration of genotypic and phenotypic data was useful for implementing guidelines for precision hybrid breeding schemes in fennel. 相似文献
27.
Carles Grau Romuald Ginhoux Alejandro Riera Thanh Lam Nguyen Hubert Chauvat Michel Berg Julià L. Amengual Alvaro Pascual-Leone Giulio Ruffini 《PloS one》2014,9(8)
Human sensory and motor systems provide the natural means for the exchange of information between individuals, and, hence, the basis for human civilization. The recent development of brain-computer interfaces (BCI) has provided an important element for the creation of brain-to-brain communication systems, and precise brain stimulation techniques are now available for the realization of non-invasive computer-brain interfaces (CBI). These technologies, BCI and CBI, can be combined to realize the vision of non-invasive, computer-mediated brain-to-brain (B2B) communication between subjects (hyperinteraction). Here we demonstrate the conscious transmission of information between human brains through the intact scalp and without intervention of motor or peripheral sensory systems. Pseudo-random binary streams encoding words were transmitted between the minds of emitter and receiver subjects separated by great distances, representing the realization of the first human brain-to-brain interface. In a series of experiments, we established internet-mediated B2B communication by combining a BCI based on voluntary motor imagery-controlled electroencephalographic (EEG) changes with a CBI inducing the conscious perception of phosphenes (light flashes) through neuronavigated, robotized transcranial magnetic stimulation (TMS), with special care taken to block sensory (tactile, visual or auditory) cues. Our results provide a critical proof-of-principle demonstration for the development of conscious B2B communication technologies. More fully developed, related implementations will open new research venues in cognitive, social and clinical neuroscience and the scientific study of consciousness. We envision that hyperinteraction technologies will eventually have a profound impact on the social structure of our civilization and raise important ethical issues. 相似文献
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Mario Prandini Gemma Gherson Alessandro Salvaterra Giulio Benamati Gino Zambanini Silvia Conci 《Aerobiologia》1992,8(1):38-45
Summary A study to evaluate and define the atmospheric pollen concentration in Trentino was carried out through the aerobiologic sampling in three localities chosen according to their different climatic conditions.1375 patients with pollinosis living in Trentino were studied retrospectively over the period ranging from 1986 to 1988 and selected according to the area they came from.Results have proved that the most allergenic pollen types are the following: Poaceae, Urticaceae (Parietaria), Compositae (Artemisia) and the tree pollen of Betulaceae and Corylaceae (Alnus, Betula, Corylus), and that pollinosis caused by such pollen, types has different features and frequencies according to the different localities.As far as symptoms are concerned, our data shows that rhinoconjuntivitis is more frequent in those patients who are allergic toParietaria while asthma results being more frequent in patients who are allergic to tree pollen. 相似文献
29.
Giulio Bernardi Emiliano Ricciardi Lorenzo Sani Anna Gaglianese Alessandra Papasogli Riccardo Ceccarelli Ferdinando Franzoni Fabio Galetta Gino Santoro Rainer Goebel Pietro Pietrini 《PloS one》2013,8(10)
The present study was designed to investigate the brain functional architecture that subserves visuo-spatial and motor processing in highly skilled individuals. By using functional magnetic resonance imaging (fMRI), we measured brain activity while eleven Formula racing-car drivers and eleven ‘naïve’ volunteers performed a motor reaction and a visuo-spatial task. Tasks were set at a relatively low level of difficulty such to ensure a similar performance in the two groups and thus avoid any potential confounding effects on brain activity due to discrepancies in task execution. The brain functional organization was analyzed in terms of regional brain response, inter-regional interactions and blood oxygen level dependent (BOLD) signal variability. While performance levels were equal in the two groups, as compared to naïve drivers, professional drivers showed a smaller volume recruitment of task-related regions, stronger connections among task-related areas, and an increased information integration as reflected by a higher signal temporal variability. In conclusion, our results demonstrate that, as compared to naïve subjects, the brain functional architecture sustaining visuo-motor processing in professional racing-car drivers, trained to perform at the highest levels under extremely demanding conditions, undergoes both ‘quantitative’ and ‘qualitative’ modifications that are evident even when the brain is engaged in relatively simple, non-demanding tasks. These results provide novel evidence in favor of an increased ‘neural efficiency’ in the brain of highly skilled individuals. 相似文献
30.
Papazoglou D Augello G Tagliaferri M Savia G Marzullo P Maltezos E Liuzzi A 《Obesity (Silver Spring, Md.)》2006,14(12):2217-2223
Objective: To examine the reliability and validity of the SenseWear Pro 2 Armband (SWA; Body Media, Pittsburgh, PA) during rest and exercise compared with indirect calorimetry (IC) in obese individuals. Research Methods and Procedures: Energy expenditure was assessed during rest with the SWA and IC in 142 obese adults (37 men and 105 women, BMI = 42.3 ± 7.0) and in 25 lean and overweight adults (BMI = 25.3 ± 3.2) who were used as a comparison group. Twenty‐nine of the obese adults also participated in three separate short exercise sessions including cycle ergometry, stair stepping, and treadmill walking. Results: The repeatability of SWA estimates in obese subjects was high (r = 0.88, p < 0.001). The SWA generally underestimated the resting energy expenditure (REE) (1811 ± 346 vs. 1880 ± 382 kcal/d) and highly overestimated the energy expenditure during the exercise sessions in obese individuals. REE estimations by SWA were significantly correlated with fat‐free mass (r = 0.88, p < 0.001). Bland‐Altman plots based statistical analysis for the estimated REE, and measured IC showed a low agreement (Total Error > 20% but Systematic Error < 5%) between the two methods in obese subjects, although they showed a high correlation and a very good agreement in lean and overweight patients. Discussion: The SWA is an easy to handle, practical, new portable device for measuring energy expenditure. The accuracy of the SWA appeared to be poor in the obese subjects we examined, especially those with high REE both in rest and exercise. We believe that it is necessary to incorporate new, obesity‐specific algorithms in the relative software. 相似文献