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111.
N. B. RODRIGUES M. R. SILVA M. M. PUCCI D. J. MINCHELLA R. SORENSEN P. T. LOVERDE A. J. ROMANHA G. OLIVEIRA 《Molecular ecology resources》2007,7(2):263-265
Microsatellite markers for Schistosoma mansoni were developed using four genomic microsatellite‐enriched libraries. Microsatellites were observed in 65.4% of all sequences. Primer pairs were designed and tested for 23 loci. Eighteen loci produced amplification products, out of which 11 were polymorphic and were further characterized on 100 individuals of S. mansoni. Two to 19 alleles per locus were detected. The average values of expected and observed heterozygosities among the 11 loci were 0.79 and 0.59, respectively. 相似文献
112.
Wordsworth S Buchanan J Regan R Davison V Smith K Dyer S Campbell C Blair E Maher E Taylor J Knight SJ 《Genomic Medicine》2007,1(1-2):35-45
Array based comparative genomic hybridisation (aCGH) is a powerful technique for detecting clinically relevant genome imbalance
and can offer 40 to > 1000 times the resolution of karyotyping. Indeed, idiopathic learning disability (ILD) studies suggest
that a genome-wide aCGH approach makes 10–15% more diagnoses involving genome imbalance than karyotyping. Despite this, aCGH
has yet to be implemented as a routine NHS service. One significant obstacle is the perception that the technology is prohibitively
expensive for most standard NHS clinical cytogenetics laboratories. To address this, we investigated the cost-effectiveness
of aCGH versus standard cytogenetic analysis for diagnosing idiopathic learning disability (ILD) in the NHS. Cost data from
four participating genetics centres were collected and analysed. In a single test comparison, the average cost of aCGH was
£442 and the average cost of karyotyping was £117 with array costs contributing most to the cost difference. This difference
was not a key barrier when the context of follow up diagnostic tests was considered. Indeed, in a hypothetical cohort of 100 ILD
children, aCGH was found to cost less per diagnosis (£3,118) than a karyotyping and multi-telomere FISH approach (£4,957).
We conclude that testing for genomic imbalances in ILD using microarray technology is likely to be cost-effective because
long-term savings can be made regardless of a positive (diagnosis) or negative result. Earlier diagnoses save costs of additional
diagnostic tests. Negative results are cost-effective in minimising follow-up test choice. The use of aCGH in routine clinical
practice warrants serious consideration by healthcare providers.
Copyright statement The Corresponding Author has the right to grant on behalf of all authors and does grant on behalf of all authors, an exclusive
licence (or non exclusive for government employees) on a worldwide basis to the BMJ Publishing Group Ltd, and its Licensees
to permit this article (if accepted) to be published in BMJ editions and any other BMJPGL products and to exploit all subsidiary
rights, as set out in our licence (bmj.com/advice/copyright.shtml).
Authorship The authors included on this paper fulfil the criteria of authorship and no one who fulfils the criteria has been excluded
from authorship. The authors made a substantial contribution to the conception, design, analysis and interpretation of data.
They were involved in drafting the article or revising it critically for important intellectual content and approving the
version to be published.
Contributorship Sarah Wordsworth (Guarantor): Planning, conducting and reporting work, interpretation of data, drafting and revising article.
James Buchanan: Conducting and reporting work, interpretation of data, revising article.
Regina Regan: Completing costing questionnaire, providing protocol details, other costing information, interpretation of data,
information about learning disability and genome imbalance and revising article.
Val Davison: Completing costing questionnaire, providing protocol details, sharing overall laboratory experience and drafting
article.
Kim Smith: Completing costing questionnaire, providing protocol details, drafting article.
Sara Dyer: Completing costing questionnaire and providing protocol details.
Carolyn Campbell: Completing costing questionnaire and providing protocol details.
Edward Blair: Critical appraisal of article for clinical content and revising article.
Eddy Maher: Completing costing questionnaire, providing protocol details, sharing overall laboratory experience and drafting
article.
Jenny Taylor: Planning and facilitating work between centres. Drafting and revising article.
Samantha JL Knight: Completing costing questionnaire, providing protocol details, other costing information, interpretation
of data, providing information about learning disability and genome imbalance, drafting and revising article.
Jenny Taylor and Samantha JL Knight contributed equally to the work presented. 相似文献
113.
Tong-De Bie Ya-Ping Cao Pei-Du Chen 《植物学报(英文版)》2007,49(11):1619-1626
Haynaldia villosa possesses a lot of important agronomic traits and has been a powerful gene resource for wheat improvement. However, only several wheat-H, villosa translocation lines have been reported so far. In this study, we attempted to develop an efficient method for inducing wheat-H, villosa chromosomal translocations. Triticum durum- Haynaldia villosa amphiploid pollen treated with 1 200 rad ^60Co-y-rays was pollinated to Triticum aestivum cv. 'Chinese Spring'. Ninety-eight intergeneric translocated chromosomes between T. durum and H. villosa were detected by genomic in situ hybridization in 44 of 61 M1 plants, indicating a translocation occurrence frequency of 72.1%; much higher than ever reported. There were 26, 62 and 10 translocated chromosomes involving whole arm translocations, terminal translocations, and intercarlary translocations, respectively. Of the total 108 breakage-fusion events, 79 involved interstitial regions and 29 involved centric regions. The ratio of small segment terminal translocations (W.W-V) was much higher than that of large segment terminal translocations (W-V.V). All of the M1 plants were self-sterile, and their backcross progeny was all obtained with 'Chinese Spring' as pollen donors. Transmission analysis showed that most of the translocations were transmittable. This study provides a new strategy for rapid mass production of wheat-alien chromosomal translocations, especially terminal translocations that will be more significant for wheat improvement. 相似文献
114.
Gardner BR Strickland MJ Correa A 《Birth defects research. Part A, Clinical and molecular teratology》2007,79(7):559-564
BACKGROUND: Although many birth defects surveillance programs incorporate georeferenced records into their databases, practical methods for routine spatial surveillance are lacking. We present a macroprogram written for the software package R designed for routine exploratory spatial analysis of birth defects data, the Automated Spatial Surveillance Program (ASSP), and present an application of this program using spina bifida prevalence data for metropolitan Atlanta. METHODS: Birth defects surveillance data were collected by the Metropolitan Atlanta Congenital Defects Program. We generated ASSP maps for two groups of years that correspond roughly to the periods before (1994-1998) and after (1999-2002) folic acid fortification of flour. ASSP maps display census tract-specific spina bifida prevalence, smoothed prevalence contours, and locations of statistically elevated prevalence. We used these maps to identify areas of elevated prevalence for spina bifida. RESULTS: We identified a large area of potential concern in the years following fortification of grains and cereals with folic acid. This area overlapped census tracts containing large numbers of Hispanic residents. CONCLUSIONS: The potential utility of ASSP for spatial disease monitoring was demonstrated by the identification of areas of high prevalence of spina bifida and may warrant further study and monitoring. We intend to further develop ASSP so that it becomes practical for routine spatial monitoring of birth defects. 相似文献
115.
116.
完整的线粒体基因组已被广泛应用于分子进化、基因组学、系统发育等方面的研究。蚜虫是一类重要的农林业害虫, 但目前公开报道的蚜虫完整线粒体基因组非常有限, 因此获得更多的基因组数据对相关研究具有重要价值。本文报道了榕毛管蚜(Greenidea ficicola)、橘二叉蚜(Aphis aurantia)和油杉纩蚜(Mindarus keteleerifoliae) 3种蚜虫的完整线粒体基因组的序列、详细注释信息、基因结构图、密码子使用情况等。该数据集可为昆虫系统发育关系、种群分化格局、害虫防治等方面的工作提供帮助。 相似文献
117.
Xiaoqin Zhang Tao Tong Bin Tian Yunxia Fang Jiangjie Pan Junjun Zheng Dawei Xue 《Phyton》2019,88(3):253-260
Barley (Hordeum vulgare L.) is one of the most Aluminum (Al) sensitive cereal species. In this study, the physiological, biochemical, and molecular response of barley seedlings to Al treatment was examined to gain insight into Al response and tolerance mechanisms. The results showed that superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) activity were inhibited to different degrees following Al exposure. The MDA content also significantly increased with increasing Al concentrations. SRAP results indicated significant differences between Al treatments and controls in terms of SRAP profile, and the genomic template stability (GTS) decreased with increasing Al concentration and duration. These integrative results help to elucidate the underlying mechanisms that the barley response to Al toxicity. 相似文献
118.
Christine R. Beck Claudia M.B. Carvalho Zeynep C. Akdemir Fritz J. Sedlazeck Xiaofei Song Qingchang Meng Jianhong Hu Harsha Doddapaneni Zechen Chong Edward S. Chen Philip C. Thornton Pengfei Liu Bo Yuan Marjorie Withers Shalini N. Jhangiani Divya Kalra Kimberly Walker Adam C. English James R. Lupski 《Cell》2019,176(6):1310-1324.e10
119.
Aleksei G. Menzorov Konstantin E. Orishchenko Veniamin S. Fishman Anastasia A. Shevtsova Roman V. Mungalov Inna E. Pristyazhnyuk Elena A. Kizilova Natalia M. Matveeva Natalia Alenina Michael Bader Nikolai B. Rubtsov Oleg L. Serov 《Journal of cellular biochemistry》2019,120(10):17208-17218
Neuronal tracing is a modern technology that is based on the expression of fluorescent proteins under the control of cell type–specific promoters. However, random genomic integration of the reporter construct often leads to incorrect spatial and temporal expression of the marker protein. Targeted integration (or knock-in) of the reporter coding sequence is supposed to provide better expression control by exploiting endogenous regulatory elements. Here we describe the generation of two fluorescent reporter systems: enhanced green fluorescent protein (EGFP) under pan-neural marker class III β-tubulin (Tubb3) promoter and mEos2 under serotonergic neuron-specific tryptophan hydroxylase 2 (Tph2) promoter. Differentiation of Tubb3-EGFP embryonic stem (ES) cells into neurons revealed that though Tubb3-positive cells express EGFP, its expression level is not sufficient for the neuronal tracing by routine fluorescent microscopy. Similarly, the expression levels of mEos2-TPH2 in differentiated ES cells was very low and could be detected only on messenger RNA level using polymerase chain reaction-based methods. Our data shows that the use of endogenous regulatory elements to control transgene expression is not always beneficial compared with the random genomic integration. 相似文献
120.
Genomic instability has been accepted as providing a phenotypic variety of malignant cells within a developing tumour. Defects in genetic recombination can often lead to phenotypic differences; therefore, it is possible that metastatic variant cell lines exhibit their particular phenotype as a result of an altered ability to catalyse homologous recombination. We have investigated recombination efficiency in B16 melanoma metastatic variants, using a plasmid, pDR, as a recombination substrate. The plasmid contains two truncated, nontandem but overlapping segments of the neomycin resistance gene (neo 1 and neo 2), separated by the functional gpt gene unit. Only a successful recombination of the two neo segments will generate a functionally intact neomycin gene. Extrachromosomal recombination here was a transient measure of the cells to recombine the neo fragments in an intra- or intermolecular manner. Extrachromosomal recombination frequencies were higher in the high metastasis variants (BL6, ML8) compared with the low metastatic F1 cells. On the other hand, the frequency of chromosomal recombination (after plasmid integration) was higher for the low metastasis (F1) cell line compared with the highly metastatic variants, BL6 and ML8. Since the recombination assay measures only successful recombination events, we have interpreted the observed higher incidence of chromosomal recombination in the low metastatic variant line as indicative of a more stable genome. Similarly, a higher inherent instability in the genome of the high metastasis variants would render these less efficient at producing and maintaining successful recombination events, and this was found to be true by Southern analysis. The results presented show that frequency of recombination may be adduced as evidence for implicating genomic instability in the generation of variant cell populations during metastatic spread. Such an interpretation is also compatible with the Nowell hypothesis for tumour progression. © 1996 Wiley-Liss, Inc. 相似文献