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1.
Michael P. Gustafson Yi Lin Mary L. Maas Virginia P. Van Keulen Patrick B. Johnston Tobias Peikert Dennis A. Gastineau Allan B. Dietz 《PloS one》2015,10(3)
The development of flow cytometric biomarkers in human studies and clinical trials has been slowed by inconsistent sample processing, use of cell surface markers, and reporting of immunophenotypes. Additionally, the function(s) of distinct cell types as biomarkers cannot be accurately defined without the proper identification of homogeneous populations. As such, we developed a method for the identification and analysis of human leukocyte populations by the use of eight 10-color flow cytometric protocols in combination with novel software analyses. This method utilizes un-manipulated biological sample preparation that allows for the direct quantitation of leukocytes and non-overlapping immunophenotypes. We specifically designed myeloid protocols that enable us to define distinct phenotypes that include mature monocytes, granulocytes, circulating dendritic cells, immature myeloid cells, and myeloid derived suppressor cells (MDSCs). We also identified CD123 as an additional distinguishing marker for the phenotypic characterization of immature LIN-CD33+HLA-DR- MDSCs. Our approach permits the comprehensive analysis of all peripheral blood leukocytes and yields data that is highly amenable for standardization across inter-laboratory comparisons for human studies. 相似文献
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Development and evaluation of the polymerase chain reaction to detect Mycoplasma genitalium 总被引:11,自引:0,他引:11
The polymerase chain reaction (PCR) was developed to detect Mycoplasma genitalium. Oligonucleotide primers were used to amplify a 374 bp region of the attachment protein of the mycoplasma. DNA from three strains of M. genitalium tested gave a characteristic PCR product which was not seen with DNA from any other source. As little as 10(-15) g of M. genitalium DNA could be detected and it was found in the vagina of progesterone-treated BALB/c mice inoculated with M. genitalium organisms later than they could be cultured from this site, but not in mice that never became colonised vaginally. 相似文献
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S Gilfillan S Aiso D Smilek D L Woodland E Palmer H O McDevitt 《Journal of immunology (Baltimore, Md. : 1950)》1991,147(12):4074-4081
The effects of quantitative differences in class II cell surface expression have been difficult to address in intact animals. This study uses several lines of H-2s/s mice carrying an A beta k transgene that differ significantly in terms of class II cell surface expression. Due to inefficient chain pairing, mice carrying 60 to 65 copies of this transgene express only low levels of A alpha s/A beta k on the cell surface, and cell surface expression of the endogenous A alpha s/A beta s complex (and total Ia) is severely reduced (to 7-15% control levels). The significant decrease in class II cell surface expression in the thymic cortex of these mice did not affect the frequency of peripheral T cells expressing at least 10 distinct TCR V beta chains. However, T cell proliferative responses to the A alpha s/A beta s-restricted peptide MBP 89-101 were abrogated in high copy number A beta k mice. Experiments using bone marrow chimeras demonstrated that both inefficient Ag presentation and failure to positively select appropriate T cells contributed to this lack of response. Inefficient Ag presentation was clearly the dominant defect, and the density of class II cell surface expression required for positive selection appeared to be quite low. 相似文献
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Janne Alahuhta Sarian Kosten Munemitsu Akasaka Dominique Auderset Mattia M. Azzella Rossano Bolpagni Claudia P. Bove Patricia A. Chambers Eglantine Chappuis John Clayton Mary de Winton Frauke Ecke Esperança Gacia Gana Gecheva Patrick Grillas Jennifer Hauxwell Seppo Hellsten Jan Hjort Mark V. Hoyer Christiane Ilg Agnieszka Kolada Minna Kuoppala Torben Lauridsen En Hua Li Balázs A. Lukács Marit Mjelde Alison Mikulyuk Roger P. Mormul Jun Nishihiro Beat Oertli Laila Rhazi Mouhssine Rhazi Laura Sass Christine Schranz Martin Søndergaard Takashi Yamanouchi Qing Yu Haijun Wang Nigel Willby Xiao Ke Zhang Jani Heino 《Journal of Biogeography》2017,44(8):1758-1769
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Patterns of mobilization of calcium,magnesium, and phosphorus by embryonic yellow-headed blackbirds(Xanthocephalus xanthocephalus) 总被引:1,自引:0,他引:1
Mary J. Packard Gary C. Packard 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1991,160(6):649-654
Summary Embryonic blackbirds(Xanthocephalus xanthocephalus) obtain most of their calcium from the eggshell (85 90%), but all of their phosphorus comes from reserves in the yolk (80–85%) and albumen (15–20%). Approximately equal amounts of magnesium are supplied by the eggshell, the yolk, and the albumen. Yolk is depleted of magnesium and phosphorus during embryogenesis, but excess calcium absorbed from the eggeshell is stored in the yolk. Consequently reserves of calcium in the yolk actually increase 8-fold during embryonic development. Our results reveal that altricial birds manifest patterns of mobilization and deposition of calcium and other elements similar to those described for precocial species. Evolution of altriciality from precocity evidently did not entail major changes in how embryonic birds meet the challenge of obtaining the calcium, magnesium, and phosphorus required for development. 相似文献
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Justyna McIntyre Mary P. McLenigan Ekaterina G. Frank Xiaoxia Dai Wei Yang Yinsheng Wang Roger Woodgate 《The Journal of biological chemistry》2015,290(45):27332-27344
Human DNA polymerases (pols) η and ι are Y-family DNA polymerase paralogs that facilitate translesion synthesis past damaged DNA. Both polη and polι can be monoubiquitinated in vivo. Polη has been shown to be ubiquitinated at one primary site. When this site is unavailable, three nearby lysines may become ubiquitinated. In contrast, mass spectrometry analysis of monoubiquitinated polι revealed that it is ubiquitinated at over 27 unique sites. Many of these sites are localized in different functional domains of the protein, including the catalytic polymerase domain, the proliferating cell nuclear antigen-interacting region, the Rev1-interacting region, and its ubiquitin binding motifs UBM1 and UBM2. Polι monoubiquitination remains unchanged after cells are exposed to DNA-damaging agents such as UV light (generating UV photoproducts), ethyl methanesulfonate (generating alkylation damage), mitomycin C (generating interstrand cross-links), or potassium bromate (generating direct oxidative DNA damage). However, when exposed to naphthoquinones, such as menadione and plumbagin, which cause indirect oxidative damage through mitochondrial dysfunction, polι becomes transiently polyubiquitinated via Lys11- and Lys48-linked chains of ubiquitin and subsequently targeted for degradation. Polyubiquitination does not occur as a direct result of the perturbation of the redox cycle as no polyubiquitination was observed after treatment with rotenone or antimycin A, which both inhibit mitochondrial electron transport. Interestingly, polyubiquitination was observed after the inhibition of the lysine acetyltransferase KATB3/p300. We hypothesize that the formation of polyubiquitination chains attached to polι occurs via the interplay between lysine acetylation and ubiquitination of ubiquitin itself at Lys11 and Lys48 rather than oxidative damage per se. 相似文献
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