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21.
Brown NL Knott L Halligan E Yarram SJ Mansell JP Sandy JR 《Development, growth & differentiation》2003,45(2):153-165
The mammalian face is assembled in utero in a series of complex and interdependent molecular, cell and tissue processes. The orofacial complex appears to be exquisitely sensitive to genetic and environmental influence and this explains why clefts of the lip and palate are the most common congenital anomaly in humans (one in 700 live births). In this study, microarray technology was used to identify genes that may play pivotal roles in normal murine palatogenesis. mRNA was isolated from murine embryonic palatal shelves oriented vertically (before elevation), horizontally (following elevation, before contact), and following fusion. Changes in gene expression between the three different stages were analyzed with GeneChip microarrays. A number of genes were upregulated or downregulated, and large changes were seen in the expression of loricrin, glutamate decarboxylase, gamma-amino butyric acid type A receptor beta3 subunit, frizzled, Wnt-5a, metallothionein, annexin VIII, LIM proteins, Sox1, plakophilin1, cathepsin K and creatine kinase. In this paper, the changes in genetic profile of the developing murine palate are presented, and the possible role individual genes/proteins may play during normal palate development are discussed. Candidate genes with a putative role in cleft palate are also highlighted. 相似文献
22.
Cloned transchromosomic calves producing human immunoglobulin 总被引:16,自引:0,他引:16
23.
Raje MR Knott K Kharel Y Bissel P Lynch KR Santos WL 《Bioorganic & medicinal chemistry》2012,20(1):183-194
Sphingosine kinase (SphK) has emerged as an attractive target for cancer therapeutics due to its role in cell survival. SphK phosphorylates sphingosine to form sphingosine 1-phosphate (S1P), which has been implicated in cancer growth and survival. SphK exists as two different isotypes, namely SphK1 and SphK2, which play different roles inside the cell. In this report, we describe SphK inhibitors based on the immunomodulatory drug, FTY720, which is phosphorylated by SphK2 to generate a S1P mimic. Structural modification of FTY720 provided a template for synthesizing new inhibitors. A diversity-oriented synthesis generated a library of SphK inhibitors with a novel scaffold and headgroup. We have discovered subtype selective inhibitors with K(i)'s in the low micromolar range. This is the first report describing quaternary ammonium salts as SphK inhibitors. 相似文献
24.
Background
Clinicians who assess and treat patients for scoliosis typically use parameters that are all visible from the posterior view. Radiographs assess the internal spinal deformity, but do not directly evaluate body shape, either posterior or anterior. This is problematic, as the patient is most concerned about the way they appear in the mirror. An objective set of anterior measurements is needed to help quantify the anterior asymmetry that is present in scoliosis.Methods
The design of this system of assessment was developed as a consensus of thinking from four points of view. A spine surgeon provided the musculoskeletal structural perspective. A plastic surgeon specializing in breast reconstruction provided the aesthetic and soft tissue perspective. A surface topography researcher provided the imaging perspective, and a scoliosis patient provided the self-perception and emotional perspective.Using an iterative process, a series of potential measurement parameters using surface topography measurements were considered, debated, and ultimately selected to be part of a system of measurement that provides an overall assessment of anterior trunk asymmetry.Results
An anterior surface topography scan in the relaxed, standing position was taken of the scoliosis patient. The computer provides a 3D topographical model that is used to complete measurements that can be combined to achieve an Anterior Aesthetic Deformity Score. Shoulder parameters, including shoulder height difference and shoulder slope difference, make up 40 % of the total score. Breast asymmetry, including nipple height difference and sternal notch-to-nipple distance, make up 30 % of the total score. Waist asymmetry makes up the final 30 % of the score, providing an objective and quantifiable measure of anterior trunk deformity.Conclusions
These measurements provide an objective, systematic evaluation of anterior trunk asymmetry that can be used in the assessment of patients with scoliosis. Clinical research should now be done to validate this system and show that it is reproducible in a variety of settings and patients.25.
Carl R Harrington Sacha Lucchini Karyn P Ridgway Udo Wegmann Tracy J Eaton Jay CD Hinton Michael J Gasson Arjan Narbad 《BMC microbiology》2008,8(1):195
Background
The human gastrointestinal (GI) tract contains a diverse collection of bacteria, most of which are unculturable by conventional microbiological methods. Increasingly molecular profiling techniques are being employed to examine this complex microbial community. The purpose of this study was to develop a microarray technique based on 16S ribosomal gene sequences for rapidly monitoring the microbial population of the GI tract. 相似文献26.
Identification of aminopyrimidine‐sulfonamides as potent modulators of Wag31‐mediated cell elongation in mycobacteria 下载免费PDF全文
János Pató Gaëlle S. Kolly Jana Korduláková Martin Forbak Joanna C. Evans Rita Székely Jan Rybniker Zuzana Palčeková Júlia Zemanová Isabella Santi François Signorino‐Gelo Liliana Rodrigues Anthony Vocat Adrian S. Covarrubias Monica G. Rengifo Kai Johnsson Sherry Mowbray Joseph Buechler Vincent Delorme Priscille Brodin Graham W. Knott José A. Aínsa Digby F. Warner Katarína Mikušová John D. McKinney Ruben C. Hartkoorn 《Molecular microbiology》2017,103(1):13-25
27.
Seasonal genetic variation associated with population dynamics of a poecilogonous polychaete worm 下载免费PDF全文
Anne Thonig Gary Thomas Banta Benni Winding Hansen K. Emily Knott 《Ecology and evolution》2017,7(23):10005-10017
Poecilogonous species show variation in developmental mode, with larvae that differ both morphologically and ecologically. The spionid polychaete Pygospio elegans shows variation in developmental mode not only between populations, but also seasonally within populations. We investigated the consequences of this developmental polymorphism on the spatial and seasonal genetic structure of P. elegans at four sites in the Danish Isefjord‐Roskilde‐Fjord estuary at six time points, from March 2014 until February 2015. We found genetic differentiation between our sampling sites as well as seasonal differentiation at two of the sites. The seasonal genetic shift correlated with the appearance of new size cohorts in the populations. Additionally, we found that the genetic composition of reproductive individuals did not always reflect the genetic composition of the entire sample, indicating that variance in reproductive success among individuals is a likely explanation for the patterns of chaotic genetic patchiness observed during this and previous studies. The heterogeneous, unpredictable character of the estuary might maintain poecilogony in P. elegans as a bet‐hedging strategy in the Isefjord‐Roskilde‐Fjord complex in comparison with other sites where P. elegans are expected to be fixed to a certain mode of development. 相似文献
28.
Molecular Ecology Resources Primer Development Consortium Austin JD Bertin A Bórquez JP Cárdenas L Cardoza TB Chapman F De Sousa AC De Souza AP Douglas KC Ellwood SR Ferriol M Garmendia A Gouin N Hargrove J Jasti M Keränen I Knott KE Konec M Kuitunen K Lima MP Linde CC Merle H Oliva ME Pérez M Saarinen E Samollow PB Scarpassa VM Segura I Smith L Trontelj P Valdivia IM Wallwork H Wellenreuther M 《Molecular ecology resources》2011,11(4):757-758
This article documents the addition of 111 microsatellite marker loci to the Molecular Ecology Resources Database. Loci were developed for the following species: Acipenser oxyrinchus desotoi, Anopheles nuneztovari sensu lato, Asellus aquaticus, Calopteryx splendens, Calopteryx virgo, Centaurea aspera, Centaurea seridis, Chilina dombeyana, Proctoeces cf. lintoni and Pyrenophora teres f. teres. 相似文献
29.
N Navaratnam D Patel R R Shah J C Greeve L M Powell T J Knott J Scott 《Nucleic acids research》1991,19(8):1741-1744
Human intestinal apolipoprotein (apo) B mRNA undergoes a C to U RNA editing at nucleotide 6666 to generate a translation stop at codon 2153, which defines the carboxy-terminal of apo B48. Here we show that two of eleven human intestinal cDNAs spanning residue 6666 were edited from a genomically-encoded C to a T at residue 6802 as well as at residue 6666. This additional editing converts Thr (ACA) codon 2198 to Ile (AUA). Synthetic RNA including the nucleotide 6802 was edited in vitro by intestinal extracts at 10-15% of the editing efficiency of nucleotide 6666. A sequence is identified as important for recognition by the editing activity. No secondary structural homology was identified between the two edited sites. No other sequence in the region between 6411 and 6893 nucleotides of apo B mRNA was found to be edited in vivo or in vitro. Apo B RNA editing extracts from intestine did not edit maize cytochrome oxidase II mRNA. 相似文献
30.
Precise nucleotide sequence modifications with bidirectionally cleaving class-IIS excision linkers 总被引:4,自引:0,他引:4
Bidirectionally cleaving blunt-ended DNA linkers have been constructed to generate defined nucleotide sequence modifications. The oligodeoxynucleotides (termed 'excision linkers'), contain two back-to-back recognition sites for class-IIS restriction endonucleases and provide a new instrument for modifying DNA primary structure. Following insertion of these linkers into host DNA, digestion with the cognate class-IIS enzyme results in a cleavage upstream and downstream from the adjoining enzyme recognition sites. Bidirectional cleavage efficiency can be improved by including spacer nucleotides between the two recognition sites. The number of nucleotides removed from or added to the host DNA depends upon the cleavage shift characteristic of the class-IIS enzyme, the design of the linker (including lateral spacer nucleotides to set the cleavage position), and the method used to make blunt ends from staggered ends following excision of the linker. BspMI linkers constructed in this study have been used to generate defined deletions in the ApR and TcR genes of pBR322. BsmI excision linkers are also described. 相似文献