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51.
Jeremy E. Martin Komsorn Lauprasert Eric Buffetaut Romain Liard Varavudh Suteethorn 《Palaeontology》2014,57(4):757-769
In the early 1980s, the remains of a large crocodilian, consisting of a nearly complete lower jaw, were referred to a distinct species of Sunosuchus, S. thailandicus. The specimen was recovered from a road‐cut near Nong Bua Lamphu, north‐eastern Thailand, in the upper part of the continental Phu Kradung Formation, and then considered Early to Middle Jurassic in age. Since then, this age has been revised and most of the formation is now considered Early Cretaceous, although a Late Jurassic age is possible for its lowermost part. Here, we report for the first time cranial elements associated with mandibular remains assignable to ‘S’. thailandicus. An attribution to Pholidosauridae is proposed on the basis of premaxillary morphology, and the original referral of this taxon to the goniopholidid Sunosuchus is discarded. A new genus name Chalawan now designates the originally described material of S. thailandicus. Nevertheless, the newly described specimen shares a characteristic with both ‘traditional’ Goniopholididae and Pholidosauridae: the presence of a depression located on the lateral wall of the maxilla and jugal. A phylogenetic analysis confirms the inclusion of both Goniopholididae and Pholidosauridae into a common clade, Coelognathosuchia tax. nov. Although the new Thai skull is much fragmented, its original shape is reconstructed and is compared with other pholidosaurid genera, namely Elosuchus, Meridiosaurus, Oceanosuchus, Pholidosaurus, Sarcosuchus and Terminonaris. The presence of the genus Sunosuchus being highly questionable in Thailand, it cannot be used as evidence to link the Chinese and Indochinese blocks. Instead, the recognition of a freshwater pholidosaurid in a continental formation of the Indochinese block suggests that early in their evolutionary history, these crocodilians, already known from Europe, Africa and South America, were more widely distributed along the northern margin of the Tethys than previously recognized. 相似文献
52.
Jessalyn K. Holodinsky Marilynne A. Hebert David A. Zygun Romain Rigal Simon Berthelot Deborah J. Cook Henry T. Stelfox 《PloS one》2015,10(12)
Objective
To describe rounding practices in Canadian adult Intensive Care Units (ICU) and identify opportunities for improvement.Design
Mixed methods design. Cross sectional survey of Canadian Adult ICUs (n = 180) with purposefully sampled follow-up interviews (n = 7).Measurements and Main Results
Medical directors representing 111 ICUs (62%) participated in the survey. Rounding practices varied across ICUs with the majority reporting the use of interprofessional rounds (81%) that employed an open (94%) and collaborative (86%) approach, occurred at the patient’s bedside (82%), and started at a standard time (79%) and standard location (56%). Most participants reported that patients (83%) and family members (67%) were welcome to attend rounds. Approximately half of ICUs (48%) used tools to facilitate rounds. Interruptions during rounds were reported to be common (i.e., ≥1 interruption for ≥50% of patients) in 46% of ICUs. Four themes were identified from qualitative analysis of participant responses to open-ended survey questions and interviews: multidisciplinarity, patient and family involvement, factors influencing productivity, and teaching and learning.Conclusions
There is considerable variation in current rounding practices in Canadian medical/surgical ICUs. Opportunities exist to improve ICU rounds including ensuring the engagement of essential participants, clearly defining participant roles, establishing a standardized approach to the rounding process, minimizing interruptions, modifying the role of teaching, utilizing a structured rounding tool, and developing a metric for measuring rounding quality. 相似文献53.
Odors can have repulsive effects on rodents based on two complementary adaptive behaviors: the avoidance of predator odors (potentially dangerous) and the avoidance of trigeminal stimulants (potentially noxious). The present study aimed to compare the behavioral effects on mice of odors according to their trigeminal properties and ecological significance. We used three different odors: 2,4,5-trimethylthiazoline (TMT: a fox feces odor frequently used to elicit fear-induced behaviors), toluene (a strong stimulant of the trigeminal system) and phenyl ethyl alcohol (PEA: a selective stimulant of the olfactory system). First, we checked preference and avoidance behaviors in mice with and without anosmia towards these odors to ensure their olfactory/trigeminal properties. Secondly, we used a standard test (open-field and elevated plus-maze) to assess the behaviors of mice when exposed to these odors. The results show that the anosmic and control mice both avoided TMT and toluene odors. In the open-field and the elevated plus-maze, mice exhibited "anxious" behaviors when exposed to TMT. Conversely, exposure to PEA induced "anxiolytic" effects confirmed by low blood corticosterone levels resulting from completion of the elevated plus-maze. Compared with TMT exposure, toluene exposure induced moderate "anxious" effects. 相似文献
54.
KG Koffi M Heuertz R Jans OJ Hardy GG Vendramin J Duminil 《American journal of botany》2012,99(8):e334-e336
? Premise of the study: To study the genetic structure among three morphotypes of an African rainforest tree species, Santiria trimera, nuclear microsatellite markers were isolated and characterized. ? Methods and Results: Seven polymorphic loci were isolated using a pyrosequencing-based protocol and successfully amplified on three different morphotypes of S. trimera. For six of the seven loci, there is at least one private allele for one of the three morphotypes. The mean effective number of alleles is about four for each of the three morphotypes. ? Conclusions: These microsatellite markers are promising to explore the genetic delimitation among sympatric morphotypes found in Gabonese forests and to study the spatial genetic structure within each gene pool. 相似文献
55.
Diploid/polyploid syntenic shuttle mapping and haplotype-specific chromosome walking toward a rust resistance gene (Bru1) in highly polyploid sugarcane (2n approximately 12x approximately 115) 下载免费PDF全文
Le Cunff L Garsmeur O Raboin LM Pauquet J Telismart H Selvi A Grivet L Philippe R Begum D Deu M Costet L Wing R Glaszmann JC D'Hont A 《Genetics》2008,180(1):649-660
The genome of modern sugarcane cultivars is highly polyploid ( approximately 12x), aneuploid, of interspecific origin, and contains 10 Gb of DNA. Its size and complexity represent a major challenge for the isolation of agronomically important genes. Here we report on the first attempt to isolate a gene from sugarcane by map-based cloning, targeting a durable major rust resistance gene (Bru1). We describe the genomic strategies that we have developed to overcome constraints associated with high polyploidy in the successive steps of map-based cloning approaches, including diploid/polyploid syntenic shuttle mapping with two model diploid species (sorghum and rice) and haplotype-specific chromosome walking. Their applications allowed us (i) to develop a high-resolution map including markers at 0.28 and 0.14 cM on both sides and 13 markers cosegregating with Bru1 and (ii) to develop a physical map of the target haplotype that still includes two gaps at this stage due to the discovery of an insertion specific to this haplotype. These approaches will pave the way for the development of future map-based cloning approaches for sugarcane and other complex polyploid species. 相似文献
56.
Le Diguarher T Ortuno JC Shanks D Guilbaud N Pierré A Raimbaud E Fauchère JL Hickman JA Tucker GC Casara PJ 《Bioorganic & medicinal chemistry letters》2004,14(3):767-771
A structure-activity study was performed by synthesis on N,N'-disubstitution of 3-aminobenzo[c] and [d]azepin-2-one 2 and 3 to afford potent and specific farnesyl transferase inhibitors with low nM enzymatic and cellular activities. 相似文献
57.
Sicard A Semblat JP Doerig C Hamelin R Moniatte M Dorin-Semblat D Spicer JA Srivastava A Retzlaff S Heussler V Waters AP Doerig C 《Cellular microbiology》2011,13(6):836-845
Merozoites of malaria parasites invade red blood cells (RBCs), where they multiply by schizogony, undergoing development through ring, trophozoite and schizont stages that are responsible for malaria pathogenesis. Here, we report that a protein kinase-mediated signalling pathway involving host RBC PAK1 and MEK1, which do not have orthologues in the Plasmodium kinome, is selectively stimulated in Plasmodium falciparum-infected (versus uninfected) RBCs, as determined by the use of phospho-specific antibodies directed against the activated forms of these enzymes. Pharmacological interference with host MEK and PAK function using highly specific allosteric inhibitors in their known cellular IC50 ranges results in parasite death. Furthermore, MEK inhibitors have parasiticidal effects in vitro on hepatocyte and erythrocyte stages of the rodent malaria parasite Plasmodium berghei, indicating conservation of this subversive strategy in malaria parasites. These findings have profound implications for the development of novel strategies for antimalarial chemotherapy. 相似文献
58.
Ludovic Bonhomme Romain Monclus Delphine Vincent Stéphane Claverol Valérie Labas Christophe Plomion Domenico Morabito 《Phytochemistry》2009,70(8):988-1395
Genotype and water deficit effects on leaf 2-DE protein profiles of two Populus deltoides × Populus nigra, cv. ‘Agathe_F’ and ‘Cima’, were analysed over a short-term period of 18 days in glasshouse using 4-month-old rooted cuttings and over a long-lasting period of 86 days in open field using 4-year-old rooted cuttings. Leaf proteomes were analyzed using two-dimensional gel electrophoresis, and proteins were identified after database searching from MS peptide spectra.A reliable genotype effect was observed in the leaf proteome over experiment locations, water regimes and sampling dates. Quantitative differences between genotypes were found. Most of them corresponded to proteins matching isoforms or post-translational modification variants. However, ‘Cima’ displayed the highest abundance of antioxidant enzymes.In response to water deficit, about 10% of the reproducible spots significantly varied regardless of the experiment location, among which about 25% also displayed genotype-dependent variations. As a whole, while ‘Cima’ differed from ‘Agathe_F’ by increased abundance of enzymes involved in photorespiration and in oxidative stress, ‘Agathe_F’ was mainly differentiated by increased abundance of enzymes involved in photosynthesis. 相似文献
59.
Duc R Leong-Morgenthaler PM 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2004,802(1):183-187
Heterocyclic amines, found ubiquitously in our diet, are carcinogenic and mutagenic. Among this class of compounds, 2-amino-1-methyl-6-phenylimidazo [4,5-b]pyridine (PhIP) is the most abundant. To further understand the carcinogenesis of this compound, we studied the effects of PhIP on the progression of human lymphoblastoid cells through the cell-cycle. Cells differing in p53 or mismatch repair status were used to evaluate the role of those proteins. Following PhIP-treatment, a dose and time-dependent accumulation of p53 was found in cells containing functional p53. The augmentation of the p53 protein, accompanied by increases in p21-WAF1, confirms that the p53 is activated. The increase in p53 was independent of the mismatch repair status of the cells. Perturbations in the cell-cycle were also observed. Twenty-four hours after PhIP treatment, the activation of the G2-M checkpoint was evident. Functional p53 and mismatch repair were not required for the PhIP-induced G2-M arrest. The G2-M arrests were reversible and are interpreted as necessary for the repair of the PhIP-DNA lesions. Under treatment conditions where less than 5% of the cells survived, the G2-M arrests were absent. 相似文献
60.
Comparative RFLP mapping has revealed extensive conservation of marker order in different grass genomes. However, microcolinearity studies at the sequence level have shown rapid genome evolution and many exceptions to colinearity. Most of these studies have focused on a limited size of genomic fragment and the extent of microcolinearity over large distances or across entire genomes remains poorly characterized in grasses. Here, we have investigated the microcolinearity between the rice genome and a total of 1,500 kb from physical BAC contigs on wheat chromosome 1AS. Using ESTs mapped in wheat chromosome bins as an additional source of physical data, we have identified 27 conserved orthologous sequences between wheat chromosome 1AS and a region of 1,210 kb located on rice chromosome 5S. Our results extend the orthology described earlier between wheat chromosome group 1S and rice chromosome 5S. Microcolinearity was found to be frequently disrupted by rearrangements which must have occurred after the divergence of wheat and rice. At the Lr10 orthologous loci, microrearrangements were due to the insertion of mobile elements, but also originated from gene movement, amplification, deletion and inversion. These mechanisms of genome evolution are at the origin of the mosaic conservation observed between the orthologous regions. Finally, in silico mapping of wheat genes identified an intragenomic colinearity between fragments from rice chromosome 1L and 5S, suggesting an ancestral segmental duplication in rice.Electronic Supplementary Material Supplementary material is available in the online version of this article at 相似文献