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101.
The genomic and gene organisation of 5S rDNA clusters have been extensively characterized in bony fish and eukaryotes, providing
general issues for understanding the molecular evolution of this multigene DNA family. By contrast, the 5S rDNA features have
been rarely investigated in cartilaginous fish (only three species). Here, we provide evidence for a dual 5S rDNA gene system
in the Rajidae by sequence analysis of the coding region (5S) and adjacent nontranscribed spacer (NTS) in five Mediterranean
species of rays (Rajidae), and in a large number of piscine taxa including lampreys and bony fish. As documented in several
bony fish, two functional 5S rDNA types were found here also in the rajid genome: a short one (I) and a long one (II), distinguished
by distinct 5S and NTS sequences. That the ancestral piscine genome had these two 5S rDNA loci might be argued from the occurrence
of homologous dual gene systems that exist in several fish taxa and from 5S phylogenetic relationships. An extensive analysis
of NTS-II sequences of Rajidae and Dasyatidae revealed the occurrence of large simple sequence repeat (SSR) regions that are
formed by microsatellite arrays. The localization and organization of SSR within the NTS-II are conserved in Rajiformes since
the Upper Cretaceous. The direct correlation between the SSRs extension and the NTS length indicated that they might play
a role in the maintenance of the larger 5S rDNA clusters in rays. The phylogenetic analysis indicated that NTS-II is a valuable
systematic tool limited to distantly related taxa of Rajiformes.
Electronic Supplementary Material Electronic Supplementary material is available for this article at
and accessible for authorised users.
[Reviewing Editor: Dr. Rafael Zardoya] 相似文献
102.
Mangerini R Romano P Facchiano A Damonte G Muselli M Rocco M Boccardo F Profumo A 《Analytical biochemistry》2011,(2):174-181
Although most time-of-flight (TOF) mass spectrometers come equipped with vacuum matrix-assisted laser desorption/ionization (MALDI) sources, the atmospheric pressure MALDI (API–MALDI) source is an attractive option because of its ability to be coupled to a wide range of analyzers. This article describes the use of an API–MALDI source coupled to a TOF mass spectrometer for evaluation of the effects of medium- and long-term storage on peptidomic profiles of cryopreserved serum samples from healthy women. Peptides were purified using superparamagnetic beads either from fresh sera or after serum storage at −80 °C for 18 months or at −20 °C for 8 years. Data were preprocessed using newly developed bioinformatic tools and then were subjected to statistical analysis and class prediction. The analyses showed a dramatic effect of storage on the abundance of several peptides such as fibrinopeptides A and B, complement fractions, bradykinin, and clusterin, indicated by other authors as disease biomarkers. Most of these results were confirmed by shadow clustering analysis, able to classify each sample in the correct group. In addition to demonstrating the suitability of the API–MALDI technique for peptidome profiling studies, our data are of relevance for retrospective studies that involve frozen sera stored for many years in biobanks. 相似文献
103.
104.
Rossetti G Cong X Caliandro R Legname G Carloni P 《Journal of molecular biology》2011,411(3):700-1431
Human (Hu) familial prion diseases are associated with about 40 point mutations of the gene coding for the prion protein (PrP). Most of the variants associated with these mutations are located in the globular domain of the protein. We performed 50 ns of molecular dynamics for each of these mutants to investigate their structure in aqueous solution. Overall, 1.6 μs of molecular dynamics data is presented. The calculations are based on the AMBER(parm99) force field, which has been shown to reproduce very accurately the structural features of the HuPrP wild type and a few variants for which experimental structural information is available. The variants present structural determinants different from those of wild-type HuPrP and the protective mutation HuPrP(E219K-129M). These include the loss of salt bridges in α2-α3 regions and the loss of π-stacking interactions in the β2-α2 loop. In addition, in the majority of the mutants, the α3 helix is more flexible and Y169 is more solvent exposed. The presence of similar traits in this large spectrum of mutations hints to a role of these fingerprints in their known disease-causing properties. Overall, the regions most affected by disease-linked mutations in terms of structure and/or flexibility are those involved in the pathogenic conversion to the scrapie form of the protein and in the interaction with cellular partners. These regions thus emerge as optimal targets for antibody- and ligand-binding studies. 相似文献
105.
A neontological approach to the problem of the origin of tetrapods consists in the examination of the available cytological and molecular data on the genome of these vertebrates. Dipnoans are a group of osteichthyian fishes, the evolutionary relationships of which with tetrapods have been disputed since their discovery. In the past, they were variously considered as being related to actinistians, tetrapods, and lower actinopterygians, though nowadays they are considered a monophyletic group, the sister group of crossopterygians. Dipnoans first appeared in the geologic record in the Early Devonian with 50 extinct genera, surviving up to date, with only three genera: Lepidosiren, Neoceratodus and Protopterus, including only six recognized species. Nothing is known of the genome of the early tetrapods, except that they and the Choanoichthyes exhibited a remarkable interspecific variability of the karyotype and of DNA content. These characteristics are often found in dipnoans and in the extant lissamphibians. Very little is known about the evolutionary karyology in the four Protopterus species and in the dipnoan clade in general. In this paper, we karyotyped ten male and female specimens of P. annectens (2n=34) from Nigeria. Moreover, we localized heterochromatin and nucleolar organizer regions by using base-specific fluorochromes and detected the human telomeric (TTAGGG)(n) sequences on all the telomeric sites of P. annectens chromosomes. DNA was also extracted and digested with seven restriction enzymes, which revealed the probable presence of almost three different families of satellite DNA. Nuclear DNA content was identified from blood samples by flow cytometry. New genomic and karyological data were compared and discussed with those on closer genera and taxa available in literature. 相似文献
106.
Diogo Aparecido Lopes Silva Francisco Antonio Rocco Lahr Ana Laura Raymundo Pavan Yovana M. B. Saavedra Natalia Crespo Mendes Sabrina Rodrigues Sousa Roberta Sanches Aldo Roberto Ometto 《The International Journal of Life Cycle Assessment》2014,19(10):1767-1778
Purpose
Sugarcane bagasse is one of the main agro-industrial residues which can be used to produce wood-based panels. However, more investigations related to its environmental performance assessment are needed, focusing on questions such as: Does it provide environmental benefits? What are its main environmental impacts? Could it substitute wood as raw material? Accordingly, this paper presents a life cycle assessment (LCA) study of particle board manufactured with sugarcane bagasse residues.Methods
The cradle-to-gate assessment of 1 m3 of particle board made with sugarcane bagasse (PSB) considered three main subsystems: bagasse generation, bagasse distribution, and PSB production. For the inventory of PSB, dataset from two previous LCA studies related to the conventional particle board production and the ethanol life cycle for the Brazilian context were used. The allocation criterion for the bagasse generation subsystem was 9.08 % (economic base). The potential environmental impact phase was assessed by applying the CML and USEtox methods. PSB was compared with the conventional particle board manufactured in Brazil by the categories of the CML and USETox, and including land use indicators. Finally, two scenarios were analyzed to evaluate the influence of the allocation criteria and the consumption of sugarcane bagasse.Results and discussion
All hotspots identified by CML and USETox methods are mainly related to the PSB production subsystem (24–100 % of impacts) due to heavy fuel oil, electricity, and urea-formaldehyde resin supply chain. The bagasse generation subsystem was more relevant to the eutrophication category (75 % of impacts). The bagasse distribution subsystem was not relevant because the impacts on all categories were lower than 1 %. PSB can substitute the conventional particle board mainly because of its lower contribution to abiotic depletion and ecotoxicity. Regarding land use impacts, PSB showed lower values according to all indicators (38–40 % of all impacts), which is explained by the lower demand for land occupation in comparison to that of the traditional particle board.Conclusions
PSB can replace the traditional particle board due to its better environmental performance. The analysis of the economic allocation criterion was relevant only for the EP category, being important to reduce diesel and N-based fertilizers use during sugarcane cultivation. Regarding the influence of the sugarcane bagasse consumption, it is suggested that the sugarcane bagasse be mixed up to 75 % during particle board manufacturing so that good quality properties and environmental performance of panels can be provided. 相似文献107.
108.
Quantification of facial skeletal shape variation in fibroblast growth factor receptor‐related craniosynostosis syndromes
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109.
Mariana A Antunes Soraia C Abreu Fernanda F Cruz Ana Clara Teixeira Miquéias Lopes-Pacheco Elga Bandeira Priscilla C Olsen Bruno L Diaz Christina M Takyia Isalira PRG Freitas Nazareth N Rocha Vera L Capelozzi Débora G Xisto Daniel J Weiss Marcelo M Morales Patricia RM Rocco 《Respiratory research》2014,15(1)
We sought to assess whether the effects of mesenchymal stromal cells (MSC) on lung inflammation and remodeling in experimental emphysema would differ according to MSC source and administration route. Emphysema was induced in C57BL/6 mice by intratracheal (IT) administration of porcine pancreatic elastase (0.1 UI) weekly for 1 month. After the last elastase instillation, saline or MSCs (1×105), isolated from either mouse bone marrow (BM), adipose tissue (AD) or lung tissue (L), were administered intravenously (IV) or IT. After 1 week, mice were euthanized. Regardless of administration route, MSCs from each source yielded: 1) decreased mean linear intercept, neutrophil infiltration, and cell apoptosis; 2) increased elastic fiber content; 3) reduced alveolar epithelial and endothelial cell damage; and 4) decreased keratinocyte-derived chemokine (KC, a mouse analog of interleukin-8) and transforming growth factor-β levels in lung tissue. In contrast with IV, IT MSC administration further reduced alveolar hyperinflation (BM-MSC) and collagen fiber content (BM-MSC and L-MSC). Intravenous administration of BM- and AD-MSCs reduced the number of M1 macrophages and pulmonary hypertension on echocardiography, while increasing vascular endothelial growth factor. Only BM-MSCs (IV > IT) increased the number of M2 macrophages. In conclusion, different MSC sources and administration routes variably reduced elastase-induced lung damage, but IV administration of BM-MSCs resulted in better cardiovascular function and change of the macrophage phenotype from M1 to M2. 相似文献
110.
Brooks V. Udelsman Ramak Khosravi Kristin S. Miller Ethan W. Dean Matthew R. Bersi Kevin Rocco Tai Yi Jay D. Humphrey Christopher K. Breuer 《Journal of biomechanics》2014
We used a murine model to assess the evolving biomechanical properties of tissue engineered vascular grafts (TEVGs) implanted in the arterial circulation. The initial polymeric tubular scaffold was fabricated from poly(lactic acid)(PLA) and coated with a 50:50 copolymer of poly(caprolactone) and poly(lactic acid)(P[PC/LA]). Following seeding with syngeneic bone marrow derived mononuclear cells, TEVGs (n=50) were implanted as aortic interposition grafts in wild-type mice and monitored serially using ultrasound. A custom biaxial mechanical testing device was used to quantify the in vitro circumferential and axial mechanical properties of grafts explanted at 3 or 7 months. At both times, TEVGs were much stiffer than native tissue in both directions. Repeated mechanical testing of some TEVGs treated with elastase or collagenase suggested that elastin did not contribute significantly to the overall stiffness whereas collagen did contribute. Traditional histology and immunostaining revealed smooth muscle cell layers, significant collagen deposition, and increasing elastin production in addition to considerable scaffold at both 3 and 7 months, which likely dominated the high stiffness seen in mechanical testing. These results suggest that PLA has inadequate in vivo degradation, which impairs cell-mediated development of vascular neotissue having properties closer to native arteries. Assessing contributions of individual components, such as elastin and collagen, to the developing neovessel is needed to guide computational modeling that may help to optimize the design of the TEVG. 相似文献