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Biomedical subjects

J Qiu

Publications and source records attributed to J Qiu.

196 records · Page 11Linked to original sources
PubMed1991

[Localization of substance P in middle ear mucosa and peripheral auditory pathways in guinea pigs].

The distribution and intracellular localization of substance P (SP) in middle ear mucosa (MEM), cochlea and spiral ganglion (SG) were studied by immunohistochemical technique and immunoelectron microscopy. There was a widespread distribution of SP positive nerve fibers (NF) along the median and small vessels of MEM. SP-immunoreactivity (SP-IR) positive cells could be seen in the MEM near the promontorium tympani. In the Corti's organ, SP-IR positive products were located at the base of inner hair cells. The majority of positive NF emerged like strings of beads and were radially distributed from osseous spiral laminal to the Corti's organ. About 50% of the SG cells were SP-IR positive. Two types of SP-IR positive NF were found in the VIII cranial nerve by light microscopy. Small clear vesicles with a diameter of 50-70nm were localized in the cytoplasm of the type-I SG cells by immunoelectron microscopy. In the outer membrane and inside the mitochondria, SP-IR positive substances could be distinguished as an electron dense matter. The possibility of SP as an afferent neurotransmitter or modulator in cochlea and the significance of its presence in the MEM were discussed.

Animals↗
PubMed1991

Antioxidant action of certain simple phenolic compounds derived from Chinese herbs.

H2O2 and hydroxyl free radical active oxygen generation systems were utilized to define the antioxidant activities of simple phenolic compounds derived from Chinese herbs. Although the antioxidant activities of compounds differed when assessed in the two systems, all compounds tested were found to be effective at preventing red blood cell membrane lipid peroxidation, with the propyl and butyl esters of gallic acid being especially potent. No compound was able to prevent hemoglobin oxidation. All compounds but salicylic acid were found to interact dose-dependently with H2O2 and hydroxyl free radical as determined by a chemiluminescence method.

Antioxidants↗
PubMedDate not supplied

Pleiotropic signaling pathways in rapid, nongenomic action of glucocorticoid.

The traditional genomic theory of steroid action does not fully explain the rapid effects of hormonal steroids, and it is thought that the nongenomic actions mediated by a putative membrane receptor may provide a plausible explanation. Although there is a rich body of evidence to substantiate the rapid, nongenomic effects of steroid hormones, the signal transduction pathways involved have proved to be complex and pleiotropic. Based on previous studies on the rapid, nongenomic actions of glucocorticoid (GC) and the G-protein-protein kinase pathways involved, including our own studies on PC12, SK-N-SH, BT-325 cells, and synaptosomes, in this review we will discuss the issue of multiple signal transduction pathways involved in the rapid, nongenomic effects of GC.

Animals↗