Biomedical subjects

Peng Pei

Publications and source records attributed to Peng Pei.

3 recordsLinked to original sources

PubMed2005

[Expression of IgG receptor on human umbilical vein endothelial cells stimulated with TNF-alpha and IFN-gamma].

AIM: To detect the expression of IgG receptors (FcgammaR) on cytokine-stimulated human umbilical vein endothelial cells (HUVECs). METHODS: By using ELISA, immunocytochemical staining, immunofluorescent staining and RT-PCR, the expression and subtypes of FcgammaR were detected. RESULTS: Non-stimulated HUVECs expressed very low level of FcgammaRIIa. FcgammaRIIa mRNA was dramatically up-regulated upon 24 hour stimulation with tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma(IFN-gamma). ELISA results indicated that the expression of FcgammaRIIa increased 16 folds after stimulation with TNF-alpha and IFN-gamma for 3 days (P<0.01). Immunofluorescent staining showed that FcgammaRIIa was expressed on the surface of the stimulated HUVECs. CONCLUSION: TNF-alpha and IFN-gamma could increase FcgammaRIIa expression on HUVECs. The enhanced expression of FcgammaRIIa may mediate the deposition of immune complexes to blood vessels under vasculitic conditions.

Cell Line↗

PubMed2004

[Non-invasive determination of bone lead in human body using X-ray fluorescence excited by 109Cd].

A measurement system of X-ray fluorescence excited by 109Cd was set up for the in vivo measurement of bone lead. In the system, a HPGe detector (phi 10 mm x 7 mm) was used to detect the characteristic K X-rays of lead in tibia excited by gamma rays of 88.0 keV from 109Cd. By the normalization of lead X-rays to the coherent scatter, the content of bone lead was calculated from the calibration curves of the ratio (X-ray intensity: coherent intensity) against the lead concentration in tibia phantoms. The normalization technique rendered the measurement accuracy independent of tissue overlay thickness, bone shape, size, mass, and subject motion. Calibration curves obtained from a set of tibia phantoms with lead-doped plaster of Paris were linear. The results of pilot measurements showed that the contents of bone lead in the occupationally exposed workers were higher than those in the control group.

Adult↗

PubMed2003

Signaling transduction by IgG receptors.

OBJECTIVE: To review and summarize literature regarding stimulatory and inhibitory signaling pathways from different types of Fc gamma receptors (FcgammaRs). DATA SOURCE: Articles were obtained from Medline from January 1991 to April 2002. STUDY SELECTION: Over 100 English language papers and reviews published over the last 11 years were selected. RESULTS AND CONCLUSIONS: Stimulatory Fcgamma receptors include FcgammaRI, FcgammaRIIA, FcgammaRIIC, and FcgammaRIII A. They transduce signals through the immunoreceptor tyrosine-based activation motif (ITAM) in subunits or in the cytoplasmic domain. Inhibitory Fcgamma receptors, such as FcgammaRIIB, are single chain receptors, transducing signals through an immunoreceptor tyrosine-based inhibitory motif (ITIM) in cytoplasmic domains. Stimulatory signals include protein phosphorylation, increase in intracellular free calcium, the production of 1,4,5-triphosphate inositol (IP(3)) and diacylglycerol (DAG) mainly through the Src-family kinases, phosphoinositide 3-kinase (PI3-K) and phospholipase C (PLC). Inhibitory signaling has been implicated in the repression of the above activities as well as inhibition of B cell responses through Src homology 2-containing inositol phosphatase (SHIP).

Amino Acid Motifs↗