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41.
42.
Methylation of p16 and Ras association domain family protein 1a during colorectal malignant transformation 总被引:2,自引:0,他引:2
Umetani N de Maat MF Sunami E Hiramatsu S Martinez S Hoon DS 《Molecular cancer research : MCR》2006,4(5):303-309
Accurate assessment of gene methylation in formalin-fixed, paraffin-embedded archived tissue (FF-PEAT) by microdissection remains challenging because the tissue volume is small and DNA is damaged. In addition, methods for methylation assessment, such as methylation-specific PCR (MSP), require sodium bisulfite modification (SBM) on purified DNA, which causes major loss of DNA. On-slide SBM, in which DNA is modified in situ before isolation of tumor cells, eliminates DNA purification steps and allows histology-oriented assessment of gene methylation. This study describes a protocol and use of on-slide SBM using 20 FF-PEAT of colorectal cancers with intratumoral adenoma components to detect accumulation of gene methylation during colorectal malignant transformation. Deparaffinized tissue sections were incubated in sodium bisulfite solution for 8 hours at 60 degrees C, stained with hematoxylin, and then microdissected. Proteinase K lysate was directly used as a template in subsequent PCR. Using on-slide SBM, 282-bp-long bisulfite direct sequencing was possible. Yield of modified DNA was 2.6-fold greater than standard SBM on average. The mean conversion rate was 97%, and false-positive or false-negative results were not observed in subsequent MSP. Intratumoral heterogeneity by accumulation of p16 and Ras association domain family protein 1a methylation during malignant transformation were shown by MSP comparing cancer with adenoma parts within a single section. On-slide SBM is applicable in most methylation studies using FF-PEAT. It allows detailed, intratumoral analysis of methylation heterogeneity within solid tumors. On-slide SBM will significantly improve our approach and understanding of epigenetic events in minimal disease and the carcinogenic process. 相似文献
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44.
Dave C. Christophel 《American journal of botany》1973,60(1):61-66
A new Sciadopitys-like conifer is described on the basis of compression fossils of shoots and leaves found at the Smokey Tower locality in western Alberta. The specimens consist of long, strap-like leaves attached in apparent whorls and subtended by groups of scale leaves. Other scale leaves are borne in loose spirals on the shoots between whorls. These specimens represent the first record of Sciadopitys-like foliage from western North America. Comparisons are made with extant and extinct species of the genus Sciadopitys (Siebold and Zuccarini, 1841) and with the widely distributed fossil genus Sciadopitytes (Goeppert and Menge, 1883). 相似文献
45.
Dave JK Halldorsdottir VG Eisenbrey JR Raichlen JS Liu JB McDonald ME Dickie K Wang S Leung C Forsberg F 《American journal of physiology. Heart and circulatory physiology》2012,303(1):H126-H132
Right heart catheterization is often required to monitor intra-cardiac pressures in a number of disease states. Ultrasound contrast agents can produce pressure modulated subharmonic emissions that may be used to estimate right ventricular (RV) pressures. A technique based on subharmonic acoustic emissions from ultrasound contrast agents to track RV pressures noninvasively has been developed and its clinical potential evaluated. The subharmonic signals were obtained from the aorta, RV, and right atrium (RA) of five anesthetized closed-chest mongrel dogs using a SonixRP ultrasound scanner and PA4-2 phased array. Simultaneous pressure measurements were obtained using a 5-French solid state micromanometer tipped catheter. Initially, aortic subharmonic signals and systemic blood pressures were used to obtain a calibration factor in units of millimeters of mercury per decibel. This factor was combined with RA pressures (that can be obtained noninvasively) and the acoustic data from the RV to obtain RV pressure values. The individual calibration factors ranged from -2.0 to -4.0 mmHg/dB. The subharmonic signals tracked transient changes in the RV pressures within an error of 0.6 mmHg. Relative to the catheter pressures, the mean errors in estimating RV peak systolic and minimum diastolic pressures, and RV relaxation [isovolumic negative derivative of change in pressure over time (-dP/dt)] by use of the subharmonic signals, were -2.3 mmHg, -0.8 mmHg, and 2.9 mmHg/s, respectively. Overall, acoustic estimates of RV peak systolic and minimum diastolic pressures and RV relaxation were within 3.4 mmHg, 1.8 mmHg, and 5.9 mmHg/s, respectively, of the measured pressures. This pilot study demonstrates that subharmonic emissions from ultrasound contrast agents have the potential to noninvasively track in vivo RV pressures with errors below 3.5 mmHg. 相似文献
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47.
Nam P. Nguyen Lexie Smith-Raymond Vincent Vinh-Hung Paul Vos Rick Davis Anand Desai Thomas Sroka Dave Abraham Shane P. Krafft Michelle Stevie Homayoun Modarresifar Beng-Hoey Jo Misty Ceizyk 《PloS one》2013,8(3)
Purpose
The study aims to assess the feasibility of Tomotherapy-based image-guided radiotherapy (IGRT) to reduce the aspiration risk in patients with non-laryngeal and non-hypopharyngeal cancer. A retrospective review of 48 patients undergoing radiation for non-laryngeal and non-hypopharyngeal head and neck cancers was conducted. All patients had a modified barium swallow (MBS) prior to treatment, which was repeated one month following radiotherapy. Mean middle and inferior pharyngeal dose was recorded and correlated with the MBS results to determine aspiration risk.Results
Mean pharyngeal dose was 23.2 Gy for the whole group. Two patients (4.2%) developed trace aspiration following radiotherapy which resolved with swallowing therapy. At a median follow-up of 19 months (1–48 months), all patients were able to resume normal oral feeding without aspiration.Conclusion and Clinical Relevance
IGRT may reduce the aspiration risk by decreasing the mean pharyngeal dose in the presence of large cervical lymph nodes. Further prospective studies with IGRT should be performed in patients with non-laryngeal and non-hypopharyngeal head and neck cancers to verify this hypothesis. 相似文献48.
Tom Drader Kara Johnson Robert Brueggeman Dave Kudrna Andris Kleinhofs 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2009,118(4):811-820
Approaches utilizing microlinearity between related species allow for the identification of syntenous regions and orthologous
genes. Within the barley Chromosome 7H(1) is a region of high recombination flanked by molecular markers cMWG703 and MWG836.
We present the constructed physical contigs linked to molecular markers across this region using bacterial artificial chromosomes
(BAC) from the cultivar Morex. Barley expressed sequence tags (EST), identified by homology to rice chromosome 6 between the
rice molecular markers C425A and S1434, corresponded to the barley syntenous region of Chromosome 7H(1) Bins 2–5 between molecular
markers cMWG703-MWG836. Two hundred and thirteen ESTs were genetically mapped yielding 267 loci of which 101 were within the
target high recombination region while 166 loci mapped elsewhere. The 101 loci were joined by 43 other genetic markers resulting
in a highly saturated genetic map. In order to develop a physical map of the region, ESTs and all other molecular markers
were used to identify Morex BAC clones. Seventy-four BAC contigs were formed containing 2–102 clones each with an average
of 19 and a median of 13 BAC clones per contig. Comparison of the BAC contigs, generated here, with the Barley Physical Mapping
Database contigs, resulted in additional overlaps and a reduction of the contig number to 56. Within cMWG703-MWG836 are 24
agriculturally important traits including the seedling spot blotch resistance locus, Rcs5. Genetic and physical analysis of this region and comparison to rice indicated an inversion distal of the Rcs5 locus. Three BAC clone contigs spanning the Rcs5 locus were identified.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
49.
First detection of Nosema ceranae, a microsporidian parasite of European honey bees (Apis mellifera), in Canada and central USA 总被引:1,自引:0,他引:1
Williams GR Shafer AB Rogers RE Shutler D Stewart DT 《Journal of invertebrate pathology》2008,97(2):189-192
Nosema ceranae is an emerging microsporidian parasite of European honey bees, Apis mellifera, but its distribution is not well known. Six Nosema-positive samples (determined from light microscopy of spores) of adult worker bees from Canada (two each from Nova Scotia, New Brunswick, and Prince Edward Island) and two from USA (Minnesota) were tested to determine Nosema species using previously-developed PCR primers of the 16S rRNA gene. We detected for the first time N. ceranae in Canada and central USA. One haplotype of N. ceranae was identified; its virulence may differ from that of other haplotypes. 相似文献
50.
Leo S. Melchers Dave V. Thompson Ken B. Idler Saskia T. C. Neuteboom Ruud A. de Maagd Rob A. Schilperoort Paul J. J. Hooykaas 《Plant molecular biology》1988,11(2):227-237
The virulence loci play an essential role in tumor formation by Agrobacterium tumefaciens. Induction of vir gene expression by plant signal molecules is solely dependent on the virulence loci virA and virG. This study focused on the virA locus of the octopine type Ti plasmid pTi15955. The nucleic acid sequence of a 5.7-kilobase fragment encompassing virA was determined. Genetic analysis of this region revealed that virA contains one open reading frame coding for a protein of 91 639 daltons. Immunodetection with antibodies raised against a 35-kDa VirA fusion protein produced in E. coli identified the VirA product in wild-type Agrobacterium cells. Moreover, it is shown that the VirA protein is located in the cytoplasmic membrane fraction of Agrobacterium. These data confirm the proposed regulatory function of VirA whereby VirA acts as a membrane sensor protein to identify plant signal molecules in the environment. The proposed sensory function of VirA strikingly resembles the function of the chemotaxis receptor proteins of E. coli. 相似文献