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991.
David De Koeyer Katheryn Douglass Agnes Murphy Sean Whitney Lana Nolan Yong Song Walter De Jong 《Molecular breeding : new strategies in plant improvement》2010,25(1):67-90
The ideal marker system for tetraploid potato would be dosage-sensitive and have the ability to distinguish heterozygous genotypes
with multiple haplotypes within the genomic region targeted by the marker. The objective of this study was to evaluate the
utility of high-resolution DNA melting (HRM) for genotyping and polymorphism detection in diploid and tetraploid potato. Amplicon
scanning, unlabelled probe, and short amplicon assays were developed for four candidate genes affecting tuber skin and flesh
colour, and starch, and a marker linked to nematode resistance. Genotyping a set of 95 potato clones revealed several examples
of clones with three distinct haplotypes. Combined probe and amplicon analysis identified between 29 and 44 unique genotypes
for the same assays. Assays developed for four of the five target genes are suitable for marker-assisted selection in potato
breeding programs. This study illustrates the use of HRM in potato genetics. Further advances in the technology and associated
data analysis should make HRM a useful tool for basic and applied studies of potato. 相似文献
992.
993.
Jos�� Maria Pereira de Godoy Agnes Cristina Fett-Conte 《Indian journal of human genetics》2010,16(1):26-27
This case report shows a genealogical study where a woman has limb hypertrophy and her son has an association of Sturge–Weber syndrome with Klippel–Trenaunay–Weber syndrome. The Sturge–Weber and Klippel–Trenaunay–Weber syndromes appear to be different manifestations of the same affliction. Familial aggregation exists and transmission may be almost imperceptible between generations. Identification of minor manifestations may prove to be a valuable contribution to genetic counseling of families and the prevention of new cases. 相似文献
994.
The reaction of the bis(carbene) pincer ligand MeCNC with nickel acetate and Bu4NBr produced [(MeCNC)3Ni2]4+[Br]4 (2), a complex that contains the MeCNC ligand in both traditional tridentate chelating modes as well as in a unique, bridging mode between two Ni2+ ions. While 2 could not be crystallized or isolated in a pure form, the anion exchange of bromide with triflate yielded [(MeCNC)3Ni2]4+[OTf]4 (4), which could be recrystallized from methanol and isolated pure. Single-crystal X-ray analysis of 4 confirmed the unusual dual-coordination modes of the MeCNC ligand towards Ni2+ in these species, and represents the initial example of a Group 10 complex of a bridging CNC ligand. 相似文献
995.
Tcherpakov M Broday L Delaunay A Kadoya T Khurana A Erdjument-Bromage H Tempst P Qiu XB DeMartino GN Ronai Z 《Molecular biology of the cell》2008,19(11):5019-5028
Clearance of misfolded proteins from the ER is central for maintenance of cellular homeostasis. This process requires coordinated recognition, ER-cytosol translocation, and finally ubiquitination-dependent proteasomal degradation. Here, we identify an ER resident seven-transmembrane protein (JAMP) that links ER chaperones, channel proteins, ubiquitin ligases, and 26S proteasome subunits, thereby optimizing degradation of misfolded proteins. Elevated JAMP expression promotes localization of proteasomes at the ER, with a concomitant effect on degradation of specific ER-resident misfolded proteins, whereas inhibiting JAMP promotes the opposite response. Correspondingly, a jamp-1 deleted Caenorhabditis elegans strain exhibits hypersensitivity to ER stress and increased UPR. Using biochemical and genetic approaches, we identify JAMP as important component for coordinated clearance of misfolded proteins from the ER. 相似文献
996.
Yvan Vandenplas Etienne Denayer Thierry Vandenbossche Luc Vermet Bruno Hauser Jean DeSchepper Agnes Engelen 《Osteopathic Medicine and Primary Care》2008,2(1):1-4
Background
Obstructive apnea is a sleep disorder characterized by pauses in breathing during sleep: breathing is interrupted by a physical block to airflow despite effort. The purpose of this study was to test if osteopathy could influence the incidence of obstructive apnea during sleep in infants.Methods
Thirty-four healthy infants (age: 1.5–4.0 months) were recruited and randomized in two groups; six infants dropped out. The osteopathy treatment group (n = 15 infants) received 2 osteopathic treatments in a period of 2 weeks and a control group (n = 13 infants) received 2 non-specific treatments in the same period of time. The main outcome measure was the change in the number of obstructive apneas measured during an 8-hour polysomnographic recording before and after the two treatment sessions.Results
The results of the second polysomnographic recordings showed a significant decrease in the number of obstructive apneas in the osteopathy group (p = 0.01, Wilcoxon test), in comparison to the control group showing only a trend suggesting a gradual physiologic decrease of obstructive apneas. However, the difference in the decline of obstructive apneas between the groups after treatment was not significant (p = 0.43).Conclusion
Osteopathy may have a positive influence on the incidence of obstructive apneas during sleep in infants with a previous history of obstructive apneas as measured by polysomnography. Additional research in this area appears warranted. 相似文献997.
998.
Hesham M. Al-Younes Thomas Rudel Volker Brinkmann Agnes J. Szczepek Thomas F. Meyer 《Cellular microbiology》2001,3(6):427-437
Chlamydiae are obligate intracellular bacteria residing exclusively in host cell vesicles termed inclusions. We have investigated the effects of deferoxamine mesylate (DAM)-induced iron deficiency on the growth of Chlamydia pneumoniae and Chlamydia trachomatis serovar L2. In epithelial cells subjected to iron starvation and infected with either C. pneumoniae or C. trachomatis L2, small inclusions were formed, and the infectivity of chlamydial progeny was impaired. Moreover, for C. trachomatis L2, we observed a delay in homotypic fusion of inclusions. The inhibitory effects of DAM were reversed by adding exogenous iron-saturated transferrin, which restored the production of infectious chlamydiae. Electron microscopy examination of iron-deprived specimens revealed that the small inclusions contained reduced numbers of C. pneumoniae that were mostly reticulate bodies. We have previously reported specific accumulation of transferrin receptors (TfRs) around C. pneumoniae inclusions within cells grown under normal conditions. Using confocal and electron microscopy, we show here a remarkable increase in the amount of TfRs surrounding the inclusions in iron-starved cultures. It has been shown that iron is an essential factor in the growth and survival of C. trachomatis. Here, we postulate that, for C. pneumoniae also, iron is an indispensable element and that Chlamydia may use iron transport pathways of the host by attracting TfR to the phagosome. 相似文献
999.
Agnes Kittel Marta Garrido Gábor Varga 《The journal of histochemistry and cytochemistry》2002,50(4):549-556
Elevated levels of extracellular ATP have been observed in many tumors. We have localized NTPDase1/CD39, one of the principal extracellular nucleotide-hydrolyzing enzymes, in normal and cancerous human pancreas. NTPDase/E-ATPDase activity was demonstrated with an enzyme histochemical technique on cryosections of human pancreas. Acinar and duct epithelial cells were devoid of E-ATPDase activity in both normal and transformed tissue. Endothelial cells and smooth muscle around blood vessels and larger ducts showed strong activity. Nerves, connective tissue, and the beta-cells of the islets were also stained. In cancerous tissue this activity was diminished in the smooth muscle around the ducts and was absent from newly formed connective tissue. Immunostaining for CD39 supported these results but revealed the presence of inactive CD39 in the duct epithelial cells. We hypothesize that the significantly diminished activity of NTPDase1 in the tissues surrounding the ducts may be associated with the processes that lead to tumor formation in human pancreas. 相似文献
1000.
Lu SY Sheikh F Sheppard PC Fresnoza A Duckworth ML Detillieux KA Cattini PA 《Biochemical and biophysical research communications》2008,373(2):270-274
Fibroblast growth factor 16 (FGF-16) expression has previously been detected in mouse heart at mid-gestation in the endocardium and epicardium, suggesting a role in embryonic heart development. More specifically, exogenously applied FGF-16 has been shown to stimulate growth of embryonic myocardial cells in tissue explants. We have generated mice lacking FGF-16 by targeting the Fgf16 locus on the X chromosome. Elimination of Fgf16 expression resulted in embryonic death as early as day 11.5 (E11.5). External abnormalities, including hemorrhage in the heart and ventral body region as well as facial defects, began to appear in null embryos from E11.5. Morphological analysis of FGF-16 null hearts revealed cardiac defects including chamber dilation, thinning of the atrial and ventricular walls, and poor trabeculation, which were visible at E10.5 and more pronounced at E11.5. These findings indicate FGF-16 is required for embryonic heart development in mid-gestation through its positive effect on myocardial growth. 相似文献