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71.
Raffaele Ingenito Charlotte Burton Annunziata Langella Xun Chen Karolina Zytko Antonello Pessi Jun Wang Elisabetta Bianchi 《Bioorganic & medicinal chemistry letters》2010,20(1):236-239
Reverse cholesterol transport (RCT) is believed to be the primary mechanism by which HDL and its major protein apoA-I protect against atherosclerosis. Starting from the inactive 22-amino acid peptide representing the consensus sequence of the class A amphipathic helical repeats of apoA-I, we designed novel peptides able to mobilize cholesterol from macrophages in vitro, and to stimulate the formation of ‘nascent HDL’ particles, with potency comparable to the entire apoA-I protein. 相似文献
72.
Guido Cipriani Alessandro Spadotto Irena Jurman Gabriele Di Gaspero Manna Crespan Stefano Meneghetti Enrica Frare Rita Vignani Mauro Cresti Michele Morgante Mario Pezzotti Enrico Pe Alberto Policriti Raffaele Testolin 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2010,121(8):1569-1585
A collection of 1005 grapevine accessions was genotyped at 34 microsatellite loci (SSR) with the aim of analysing genetic diversity and exploring parentages. The comparison of molecular profiles revealed 200 groups of synonymy. The removal of perfect synonyms reduced the database to 745 unique genotypes, on which population genetic parameters were calculated. The analysis of kinship uncovered 74 complete pedigrees, with both parents identified. Many of these parentages were not previously known and are of considerable historical interest, e.g. Chenin blanc (Sauvignon × Traminer rot), Covè (Harslevelu selfed), Incrocio Manzoni 2–14 and 2–15 (Cabernet franc × Prosecco), Lagrein (Schiava gentile × Teroldego), Malvasia nera of Bolzano (Perera × Schiava gentile), Manzoni moscato (Raboso veronese × Moscato d’Amburgo), Moscato violetto (Moscato bianco × Duraguzza), Muscat of Alexandria (Muscat blanc à petit grain × Axina de tres bias) and others. Statistical robustness of unexpected pedigrees was reinforced with the analysis of an additional 7–30 SSRs. Grouping the accessions by profile resulted in a weak correlation with their geographical origin and/or current area of cultivation, revealing a large admixture of local varieties with those most widely cultivated, as a result of ancient commerce and population flow. The SSRs with tri- to penta-nucleotide repeats adopted for the present study showed a great capacity for discriminating amongst accessions, with probabilities of identity by chance as low as 1.45 × 10?27 and 9.35 × 10?12 for unrelated and full sib individuals, respectively. A database of allele frequencies and SSR profiles of 32 reference cultivars are provided. 相似文献
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74.
This paper demonstrates that the crystallization of 3beta-acetoxy-14alpha,15alpha-epoxy-5alpha-cholest-8-en-7-one from methanol affords the 3beta-acetoxy-9alpha-methoxy-15alpha-hydroxycholest-8(14)-en-7-one. The structure of this steroid, which shows an apparently anomalous UV absorption maximum, is determined by high field NMR experiments, supporting the coupling constant values assignments and the NOE contacts by a conformational study through theoretical calculations at the B3LYP/6-31G* level. The computational study also justifies the observed UV absorption of the steroid, thus demonstrating the usefulness of computer chemistry in providing support for the identification of unknown compounds. 相似文献
75.
Calabretta R 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2007,362(1479):403-410
The aim of this paper is to propose an interdisciplinary evolutionary connectionism approach for the study of the evolution of modularity. It is argued that neural networks as a model of the nervous system and genetic algorithms as simulative models of biological evolution would allow us to formulate a clear and operative definition of module and to simulate the different evolutionary scenarios proposed for the origin of modularity. I will present a recent model in which the evolution of primate cortical visual streams is possible starting from non-modular neural networks. Simulation results not only confirm the existence of the phenomenon of neural interference in non-modular network architectures but also, for the first time, reveal the existence of another kind of interference at the genetic level, i.e. genetic interference, a new population genetic mechanism that is independent from the network architecture. Our simulations clearly show that genetic interference reduces the evolvability of visual neural networks and sexual reproduction can at least partially solve the problem of genetic interference. Finally, it is shown that entrusting the task of finding the neural network architecture to evolution and that of finding the network connection weights to learning is a way to completely avoid the problem of genetic interference. On the basis of this evidence, it is possible to formulate a new hypothesis on the origin of structural modularity, and thus to overcome the traditional dichotomy between innatist and empiricist theories of mind. 相似文献
76.
Lepori MB Lovicu M Dessi V Zappu A Incollu S Zancan L Giacchino R Iorio R Vajro P Maggiore G Marcellini M Barbera C Pellecchia MT Simonetti R Kostic V Farci AM Solinas A De Virgiliis S Cao A Loudianos G 《Genetic testing》2007,11(3):328-332
Herein we report the results of mutation analysis of the ATP7B gene in a group of 134 Wilson disease (WD) families (268 chromosomes) prevalently of Italian origin. Using the SSCP and sequencing methods we identified 71 disease-causing mutations. Twenty-four were novel, while 19 more mutations already described, were identified in new populations in this study. A known mutation G591D showed a regional distribution, since it was only detected in 38.5% of the analyzed chromosomes in WD patients originating from Apulia, a region of South Italy. Detection of new mutations in the ATP7B gene increases our capability of molecular analysis that is essential for early diagnosis and treatment of WD. 相似文献
77.
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79.
Morana A Paris O Maurelli L Rossi M Cannio R 《Extremophiles : life under extreme conditions》2007,11(1):123-132
An open reading frame encoding a putative bi-functional β-d-xylosidase/α-l-arabinosidase (Sso3032) was identified on the genome sequence of Sulfolobus solfataricus P2, the predicted gene product showing high amino-acid sequence similarity to bacterial and eukaryal individual β-d-xylosidases and α-l-arabinosidases as well as bi-functional enzymes such as the protein from Thermoanaerobacter ethanolicus and barley. The sequence was PCR amplified from genomic DNA of S. solfataricus P2 and heterologous gene expression obtained in Escherichia coli, under optimal conditions for overproduction. Specific assays performed at 75°C revealed the presence in the transformed
E. coli cell extracts of this archaeal activity involved in sugar hydrolysis and specific for both substrates. The recombinant protein
was purified by thermal precipitation of the host proteins and ethanol fractionation and other properties, such as high thermal
activity and thermostability could be determined. The protein showed a homo-tetrameric structure with a subunit of molecular
mass of 82.0 kDa which was in perfect agreement with that deduced from the cloned gene. Northern blot analysis of the xarS gene indicates that it is specifically induced by xylan and repressed by monosaccharides like d-glucose and l-arabinose. 相似文献
80.
Bice Avallone Claudio Agnisola Raimondo Cerciello Raffaele Panzuto Palma Simoniello Patrizia Cretì Chiara Maria Motta 《Cell biology and toxicology》2015,31(6):273-283
This report describes the alterations induced by an environmentally realistic concentration of cadmium in skeletal muscle fibre organization, composition, and function in the teleost zebrafish. Results demonstrate that the ion induces a significant quantitative and qualitative deterioration, disrupting sarcomeric pattern and altering glycoprotein composition. These events, together with a mitochondrial damage, result in a significant reduction in swimming performance. In conclusion, the evidence here collected indicate that in presence of an environmental cadmium contamination, important economic (yields in fisheries/aquaculture), consumer health (fish is an important source of proteins), and ecological (reduced fitness due to reduced swimming performance) consequences can be expected. 相似文献