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31.
Bladder exstrophy–epispadias complex and triple‐X syndrome: Incidental finding or causality? 下载免费PDF全文
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Trachet B Bols J De Santis G Vandenberghe S Loeys B Segers P 《Journal of biomechanical engineering》2011,133(12):121006
Computational fluid dynamics (CFD) simulations allow for calculation of a detailed flow field in the mouse aorta and can thus be used to investigate a potential link between local hemodynamics and disease development. To perform these simulations in a murine setting, one often needs to make assumptions (e.g. when mouse-specific boundary conditions are not available), but many of these assumptions have not been validated due to a lack of reference data. In this study, we present such a reference data set by combining high-frequency ultrasound and contrast-enhanced micro-CT to measure (in vivo) the time-dependent volumetric flow waveforms in the complete aorta (including seven major side branches) of 10 male ApoE -/- deficient mice on a C57Bl/6 background. In order to assess the influence of some assumptions that are commonly applied in literature, four different CFD simulations were set up for each animal: (i) imposing the measured volumetric flow waveforms, (ii) imposing the average flow fractions over all 10 animals, presented as a reference data set, (iii) imposing flow fractions calculated by Murray's law, and (iv) restricting the geometrical model to the abdominal aorta (imposing measured flows). We found that - even if there is sometimes significant variation in the flow fractions going to a particular branch - the influence of using average flow fractions on the CFD simulations is limited and often restricted to the side branches. On the other hand, Murray's law underestimates the fraction going to the brachiocephalic trunk and strongly overestimates the fraction going to the distal aorta, influencing the outcome of the CFD results significantly. Changing the exponential factor in Murray's law equation from 3 to 2 (as suggested by several authors in literature) yields results that correspond much better to those obtained imposing the average flow fractions. Restricting the geometrical model to the abdominal aorta did not influence the outcome of the CFD simulations. In conclusion, the presented reference dataset can be used to impose boundary conditions in the mouse aorta in future studies, keeping in mind that they represent a subsample of the total population, i.e., relatively old, non-diseased, male C57Bl/6 ApoE -/- mice. 相似文献
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A. Jamsheer C. Henggeler J. Wierzba B. Loeys A. De Paepe Ch. Stheneur N. Badziąg K. Matuszewska G. Matyas A. Latos-Bieleńska 《Journal of applied genetics》2009,50(4):405-410
We report on a 2-year-old Polish girl with typical manifestations of Loeys-Dietz syndrome (LDS), a rare genetic condition
belonging to the group of Marfan-related disorders. The characteristic LDS symptoms observed in the girl included craniofacial
dysmorphism (craniosynostosis, cleft palate, hypertelorism), arachnodactyly, camptodactyly, scoliosis, joint laxity, talipes
equinovarus, translucent and hyperelastic skin, and umbilical hernia. Mild dilatation of the ascending aorta and tortuous
course of the left internal carotid artery were recognized during her second year of life. Molecular genetic testing revealed
a heterozygous missense mutation (c.1582C>T, p.R528C) in the transforming growth factor beta receptor II gene (TGFBR2). This mutation has been previously associated with LDS in 5 unrelated cases, and was never reported in patients with other
Marfan-related disorders. Comparison of the phenotypes of our patient and these 5 individuals with c.1582C>T showed that only
the hallmark triad of the syndrome — consisting of hypertelorism, aortic root dilatation/aneurysm, and cleft palate or bifid
uvula — was present in all 6 cases. Interestingly, none of the 5 individuals who underwent psychological evaluation showed
developmental delay. The pattern of all other LDS features showed interindividual variability. Our data support the recently
reported observation that symptoms of LDS can develop at a very young age, making early diagnosis and management essential
for these patients. This is the first report on a Polish infant with typical LDS symptoms caused by aTGFBR2 mutation. 相似文献
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María Moreno-Villanueva Ragen Pfeiffer Thilo Sindlinger Alan Leake Marcus Müller Thomas BL Kirkwood Alexander Bürkle 《BMC biotechnology》2009,9(1):39-9
Background
Formation and repair of DNA single-strand breaks are important parameters in the assessment of DNA damage and repair occurring in live cells. The 'Fluorimetric Detection of Alkaline DNA Unwinding (FADU)' method [Birnboim HC, Jevcak JJ. Cancer Res (1981) 41:1889–1892] is a sensitive procedure to quantify DNA strand breaks, yet it is very tedious to perform. 相似文献35.
Taxonomy lies at the heart of species conservation, yet many large New Zealand orthopterans remain undescribed. Among New Zealand’s anostostomatid wētā, Hemiandrus (ground wētā) is the most speciose genus but also the most poorly characterised and thus most in need of taxonomic and ecological work. Here we redescribe H. maculifrons and describe two new species of ground wētā previously encompassed by the specific name Hemiandrus maculifrons: Hemiandrus luna sp. nov. and H. brucei sp. nov. We also describe a morphologically similar and related species, Hemiandrus nox sp. nov.
http://zoobank.org/urn:lsid:zoobank.org:pub:71EA0879-A2F9-46B2-A105-E97A9AB25061
http://zoobank.org/References/71EA0879-A2F9-46B2-A105-E97A9AB25061 相似文献
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Previous research showed that threat-related faces, due to their intrinsic motivational relevance, capture attention more readily than neutral faces. Here we used a standard temporal order judgment (TOJ) task to assess whether negative (either angry or fearful) emotional faces, when competing with neutral faces for attention selection, may lead to a prior entry effect and hence be perceived as appearing first, especially when uncertainty is high regarding the order of the two onsets. We did not find evidence for this conjecture across five different experiments, despite the fact that participants were invariably influenced by asynchronies in the respective onsets of the two competing faces in the pair, and could reliably identify the emotion in the faces. Importantly, by systematically varying task demands across experiments, we could rule out confounds related to suboptimal stimulus presentation or inappropriate task demands. These findings challenge the notion of an early automatic capture of attention by (negative) emotion. Future studies are needed to investigate whether the lack of systematic bias of attention by emotion is imputed to the primacy of a non-emotional cue to resolve the TOJ task, which in turn prevents negative emotion to exert an early bottom-up influence on the guidance of spatial and temporal attention. 相似文献
37.
Bard JB 《Cell communication and signaling : CCS》2011,9(1):30-6
The evolutionary synthesis, the standard 20th century view of how evolutionary change occurs, is based on selection, heritable phenotypic variation and a very simple view of genes. It is therefore unable to incorporate two key aspects of modern molecular knowledge: first is the richness of genomic variation, so much more complicated than simple mutation, and second is the opaque relationship between the genotype and its resulting phenotype. Two new and important books shed some light on how we should view evolutionary change now. Evolution: a view from the 21 st century by J.A. Shapiro (2011, FT Press Science, New Jersey, USA. pp. 246. $34.99.) examines the richness of genomic variation and its implications. Transformations of Lamarckism: from Subtle Fluids to Molecular Biology edited by S.B. Gissis &; E. Jablonka (2011, MIT Press, Cambridge, USA. pp. 457) includes some 40 papers that anyone with an interest in the history of evolutionary thought and the relationship between the environment and the genome will want to read. This review discusses both books within the context of contemporary evolutionary thinking and points out that neither really comes to terms with today's key systems-biology question: how does mutation-induced variation in a molecular network generate variation in the resulting phenotype? 相似文献
38.
Mutations in KIF11 cause autosomal-dominant microcephaly variably associated with congenital lymphedema and chorioretinopathy 总被引:1,自引:0,他引:1
Ostergaard P Simpson MA Mendola A Vasudevan P Connell FC van Impel A Moore AT Loeys BL Ghalamkarpour A Onoufriadis A Martinez-Corral I Devery S Leroy JG van Laer L Singer A Bialer MG McEntagart M Quarrell O Brice G Trembath RC Schulte-Merker S Makinen T Vikkula M Mortimer PS Mansour S Jeffery S 《American journal of human genetics》2012,90(2):356-362
We have identified KIF11 mutations in individuals with syndromic autosomal-dominant microcephaly associated with lymphedema and/or chorioretinopathy. Initial whole-exome sequencing revealed heterozygous KIF11 mutations in three individuals with a combination of microcephaly and lymphedema from a microcephaly-lymphedema-chorioretinal-dysplasia cohort. Subsequent Sanger sequencing of KIF11 in a further 15 unrelated microcephalic probands with lymphedema and/or chorioretinopathy identified additional heterozygous mutations in 12 of them. KIF11 encodes EG5, a homotetramer kinesin motor. The variety of mutations we have found (two nonsense, two splice site, four missense, and six indels causing frameshifts) are all predicted to have an impact on protein function. EG5 has previously been shown to play a role in spindle assembly and function, and these findings highlight the critical role of proteins necessary for spindle formation in CNS development. Moreover, identification of KIF11 mutations in patients with chorioretinopathy and lymphedema suggests that EG5 is involved in the development and maintenance of retinal and lymphatic structures. 相似文献
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FLORIAN MENZEL TAMARA POKORNY NICO BLÜTHGEN THOMAS SCHMITT 《Ecological Entomology》2010,35(4):495-503
1. Trail‐sharing between different ant species is rare and restricted to a small number of species pairs. Its underlying mechanisms are largely unknown. For trail‐sharing to occur, two factors are required: (i) one or both species must recognise the other species or its pheromone trails and (ii) both species must tolerate each other to a certain extent to allow joint use of the trail. A species that follows another's trails can efficiently exploit the other's information on food sources contained in the pheromone trails. Hence, food competition and thus aggressive interactions between a species following another's trail and the species being followed, seem likely. 2. In the present study, we investigated interspecific trail following and interspecific aggression in trail sharing associations (i) among Polyrhachis ypsilon, Camponotus saundersi, and Dolichoderus cuspidatus, and (ii) among Camponotus rufifemur and Crematogaster modiglianii. We tested whether trail‐sharing species follow each other's pheromone trails, and whether the ants tolerated or attacked their trail‐sharing partners. In both associations, we confronted workers with pheromone trails of their associated species, and, for the former association, measured interspecific aggression among the trail‐sharing species. 3. In our assays, D. cuspidatus and C. rufifemur regularly followed heterospecific pheromone trails of P. ypsilon and C. modiglianii, respectively. However, only few workers of the remaining species followed heterospecific pheromone trails. Thus, shared trails of P. ypsilon and C. saundersi cannot be explained by interspecific trail‐following. 4. Interspecific aggression among P. ypsilon, C. saundersi, and D. cuspidatus was strongly asymmetric, C. saundersi being submissive to the other two. All three species differentiated between heterospecific workers from the same or another site, suggesting habituation to the respective trail‐sharing partners. We therefore hypothesise that differential tolerance by dominant ant species may be mediated by selective habituation towards submissive species and this way determines the assembly of trail‐sharing associations. 相似文献