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101.
Evaluation of blood pressure in feline night monkeys (Aotus azarae infulatus) under different restraint protocols
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102.
Walter A. Neves Danilo V. Bernardo João Paulo V. Atuí 《American journal of physical anthropology》2015,157(2):202-216
The Botocudo Indians were hunter‐gatherer groups that occupied the East‐Central regions of Brazil decimated during the colonial period in the country. During the 19th century, craniometric studies suggested that the Botocudo resembled more the Paleoamerican population of Lagoa Santa than typical Native Americans groups. These results suggest that the Botocudo Indians might represent a population that retained the biological characteristics of early groups of the continent, remaining largely isolated from groups that gave origin to the modern Native South American variation. Moreover, recently, some of the Botocudo remains have been shown to have mitochondrial and autosomal DNA lineages currently found in Polynesian populations. Here, we explore the morphological affinities of Botocudo skulls within a worldwide context. Distinct multivariate analyses based on 32 craniometric variables show that 1) the two individuals with Polynesian DNA sequences have morphological characteristics that fall within the Polynesian and Botocudo variation, making their assignation as Native American specimens problematic, and 2) there are high morphological affinities between Botocudo, Early Americans, and the Polynesian series of Easter Island, which support the early observations that the Botocudo can be seen as retaining the Paleoamerican morphology, particularly when the neurocranium is considered. Although these results do not elucidate the origin of the Polynesian DNA lineages among the Botocudo, they support the hypothesis that the Botocudo represent a case of late survival of ancient Paleoamerican populations, retaining the morphological characteristics of ancestral Late Pleistocene populations from Asia. Am J Phys Anthropol 157:202–216, 2015. © 2015 Wiley Periodicals, Inc. 相似文献
103.
Blocking the Expression of Both Bone Sialoprotein (BSP) and Osteopontin (OPN) Impairs the Anabolic Action of PTH in Mouse Calvaria Bone
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104.
Historical demography of freshwater mussels (Bivalvia: Unionidae): genetic evidence for population expansion and contraction during the late Pleistocene and Holocene
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Jess W. Jones Richard J. Neves Eric M. Hallerman 《Biological journal of the Linnean Society. Linnean Society of London》2015,114(2):376-397
Genetic variation was examined in two endangered mussel species, Epioblasma brevidens and Epioblasma capsaeformis, and in a non‐listed species, Lampsilis fasciola, in the Clinch River, Tennessee, USA, by screening mitochondrial DNA (mtDNA) sequences and nuclear DNA microsatellites. Patterns of mtDNA polymorphism exhibited different trends in long‐term population sizes for each species during the late Pleistocene and Holocene (~20 000 ya to present); namely, E. brevidens has declined over time, E. capsaeformis has remained demographically stable, and L. fasciola has expanded. However, analyses using microsatellites did not exhibit similar trends, perhaps because homoplasy had eliminated long‐term population signatures for the loci examined. For both marker types, long‐term effective population size (Ne) was low in E. brevidens, intermediate in E. capsaeformis, and high in L. fasciola. Moderately diverged mtDNA lineages, perhaps indicative of secondary contact, were observed in E. brevidens and E. capsaeformis. Perhaps the most surprising result of this study was the high level of genetic variation observed at both mtDNA and microsatellite DNA markers for L. fasciola, variation seemingly contrary to the relatively small demes that currently reside in the Clinch River. However, the data are consistent with known demographic and life‐history traits of these three mussel species and their fish hosts, namely that they each use hosts with different dispersal capabilities, ranging from low, moderate, and high, respectively. The low divergence of mtDNA sequence variation reported in this and other recent mussel studies indicates that considerable extant population genetic variation probably originated during the late Pleistocene and Holocene. © 2015 The Linnean Society of London, Biological Journal of the Linnean Society, 2015, 114 , 376–397. 相似文献
105.
M. Ferreira Junior S.A. Batista P.V.T Vidigal A.A.C. Cordeiro F.M.S. Oliveira L.O. Prata A.E.T. Diniz C.M. Barral R.C. Barbuto A.D. Comes I.D. Araujo D.M.M. Queiroz M.V. Caliari 《European journal of histochemistry : EJH》2015,59(2)
Infection with Helicobacter pylori strains containing high number of EPIYA-C phosphorylation sites in the CagA is associated with significant gastritis and increased risk of developing pre-malignant gastric lesions and gastric carcinoma. However, these findings have not been reproduced in animal models yet. Therefore, we investigated the effect on the gastric mucosa of Mongolian gerbil (Meriones unguiculatus) infected with CagA-positive H. pylori strains exhibiting one or three EPIYA-C phosphorilation sites. Mongolian gerbils were inoculated with H. pylori clonal isolates containing one or three EPIYA-C phosphorylation sites. Control group was composed by uninfected animals challenged with Brucella broth alone. Gastric fragments were evaluated by the modified Sydney System and digital morphometry. Clonal relatedness between the isolates was considered by the identical RAPD-PCR profiles and sequencing of five housekeeping genes, vacA i/d region and of oipA. The other virulence markers were present in both isolates (vacA s1i1d1m1, iceA2, and intact dupA). CagA of both isolates was translocated and phosphorylated in AGS cells. After 45 days of infection, there was a significant increase in the number of inflammatory cells and in the area of the lamina propria in the infected animals, notably in those infected by the CagA-positive strain with three EPIYA-C phosphorylation sites. After six months of infection, a high number of EPIYA-C phosphorylation sites was associated with progressive increase in the intensity of gastritis and in the area of the lamina propria. Atrophy, intestinal metaplasia, and dysplasia were also observed more frequently in animals infected with the CagA-positive isolate with three EPIYA-C sites. We conclude that infection with H. pylori strain carrying a high number of CagA EPIYA-C phosphorylation sites is associated with more severe gastric lesions in an animal model of H. pylori infection.Key words: Gastritis, atrophy, intestinal metaplasia, dysplasia, Mongolian gerbil, cagA EPIYA C motif 相似文献
106.
107.
Xavier NM Goulart M Neves A Justino J Chambert S Rauter AP Queneau Y 《Bioorganic & medicinal chemistry》2011,19(2):926-938
The synthesis of a series of pyranoid derivatives comprising a conjugated carbonyl function and related triazole derivatives, structurally suitable for bioactivity evaluation, was achieved in few steps starting from readily available carboxymethyl glycoside lactones (CMGL). 3-Enopyranosid-2-uloses were generated by oxidation/elimination of tri-O-acylated 2-hydroxy pyranosides. Subsequent Wittig olefination provided stereoselectively 2-C-branched-chain conjugated dienepyranosides with (E)-configuration around the exocyclic double bond. A heterogeneous CuI/Amberlyst-catalyzed ‘click’ chemistry protocol was used to convert glycosides bearing a propargyl moiety into the corresponding 1,2,3-triazoles. These new molecules were screened for their in vitro antibacterial and antifungal activities and those containing conjugated carbonyl systems demonstrated the best efficacy. (N-Dodecylcarbamoyl)methyl enone glycerosides were the most active ones among the enones tested. The ??-anomer displayed very strong activities against Bacillus cereus and Bacillus subtilis and strong activity toward Enterococcus faecalis and the fungal pathogen Penicillium aurantiogriseum. The corresponding ??-anomer presented a very strong inhibitory effect against two fungal species (Aspergillus niger and P. aurantiogriseum). (N-Dodecyl-/N-propargyl/or N-benzylcarbamoyl)methyl dienepyranosides exhibited selectively a strong activity toward E. faecalis. Further acute toxicity evaluation indicated low toxic effect of the (N-dodecylcarbamoyl)methyl enone glyceroside ??-anomer and of the carbamoylmethyl dienepyranosides N-protected with propargyl or benzyl groups. 相似文献
108.
Martins RH Gonçalves TM Neves DS Fracalossi TA Tavares EL Moretti-Ferreira D 《Genetics and molecular research : GMR》2011,10(4):3163-3168
We found evidence of autosomal dominant hereditary transmission of sulcus vocalis. Four dysphonic patients from three generations of the same family were submitted to videolaryngoscopic examination (three patients) and to direct laryngoscopy (one patient) to diagnose the hoarseness. Sulcus vocalis was diagnosed in all four patients. The finding of four affected individuals in three generations, with vertical transmission affecting man and women, is more consistent with autosomal dominant inheritance pattern; it is an etiological model that we propose for the sulcus vocalis in this pedigree. 相似文献
109.
Fernanda Vieira da Costa Frederico de Siqueira Neves Jhonathan de Oliveira Silva Marc��lio Fagundes 《Arthropod-Plant Interactions》2011,5(1):9-18
Plant development is the main factor that determines the insect-ontogeny interaction, since it leads to variations in resource
quality and availability. The aim of this study was to test the hypothesis that plant development and varying tannin concentration
leads to changes in species richness, abundance and composition of ants, free-feeding herbivores and galling insects associated
with Copaifera langsdorffii (Fabaceae). The plant ontogeny and tannin concentration effects on insects were tested on 60 individuals with height varying from 0.9
to 11.0 m. A positive correlation was observed for tree height and species richness and abundance of ants, free-feeding and
galling insects. In contrast, we did not find a significant relation between leaf tannin concentration and plant height, or
richness and abundance of the different insect guilds. The assemblage of ants (composition of species) did not change between
saplings and adults of C. langsdorffii. However, the assemblage of free-feeding herbivores and galling insects varied between the two development stages studied.
The present study reveals an ontogenetic succession pattern for herbivore insects along the C. langsdorffii growth, probably due to both indirect and direct benefits from the host plant architecture and quality. Those plants with
more complex architectures should support a wider diversity of insects, since they present higher number of sites for egg
laying, housing, feeding and better environmental conditions. This is the first work to investigate the host plant ontogeny
effect on insects in Cerrado “Savanna” vegetation. The pattern described, along with other previous studies, suggests a vast
occurrence of ontogenetic succession in tropical areas. 相似文献
110.
A finite-context (Markov) model of order k yields the probability distribution of the next symbol in a sequence of symbols, given the recent past up to depth k. Markov modeling has long been applied to DNA sequences, for example to find gene-coding regions. With the first studies came the discovery that DNA sequences are non-stationary: distinct regions require distinct model orders. Since then, Markov and hidden Markov models have been extensively used to describe the gene structure of prokaryotes and eukaryotes. However, to our knowledge, a comprehensive study about the potential of Markov models to describe complete genomes is still lacking. We address this gap in this paper. Our approach relies on (i) multiple competing Markov models of different orders (ii) careful programming techniques that allow orders as large as sixteen (iii) adequate inverted repeat handling (iv) probability estimates suited to the wide range of context depths used. To measure how well a model fits the data at a particular position in the sequence we use the negative logarithm of the probability estimate at that position. The measure yields information profiles of the sequence, which are of independent interest. The average over the entire sequence, which amounts to the average number of bits per base needed to describe the sequence, is used as a global performance measure. Our main conclusion is that, from the probabilistic or information theoretic point of view and according to this performance measure, multiple competing Markov models explain entire genomes almost as well or even better than state-of-the-art DNA compression methods, such as XM, which rely on very different statistical models. This is surprising, because Markov models are local (short-range), contrasting with the statistical models underlying other methods, where the extensive data repetitions in DNA sequences is explored, and therefore have a non-local character. 相似文献