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J Y Xie

Publications and source records attributed to J Y Xie.

11 recordsLinked to original sources

Descending facilitation from the rostral ventromedial medulla maintains nerve injury-induced central sensitization.

Nerve injury can produce hypersensitivity to noxious and normally innocuous stimulation. Injury-induced central (i.e. spinal) sensitization is thought to arise from enhanced afferent input to the spinal cord and to be critical for expression of behavioral hypersensitivity. Descending facilitatory influences from the rostral ventromedial medulla have been suggested to also be critical for the maintenance, though not the initiation, of experimental neuropathic pain. The possibility that descending facilitation from the rostral ventromedial medulla is required for the maintenance of central sensitization was examined by determining whether ablation of mu-opioid receptor-expressing cells within the rostral ventromedial medulla prevented the enhanced expression of repetitive touch-evoked FOS within the spinal cord of animals with spinal nerve ligation injury as well as nerve injury-induced behavioral hypersensitivity. Rats received a single microinjection of vehicle, saporin, dermorphin or dermorphin-saporin into the rostral ventromedial medulla and 28 days later, underwent either sham or spinal nerve ligation procedures. Animals receiving rostral ventromedial medulla pretreatment with vehicle, dermorphin or saporin that were subjected to spinal nerve ligation demonstrated both thermal and tactile hypersensitivity, and showed significantly increased expression of touch-evoked FOS in the dorsal horn ipsilateral to nerve injury compared with sham-operated controls at days 3, 5 or 10 post-spinal nerve ligation. In contrast, nerve-injured animals pretreated with dermorphin-saporin showed enhanced behaviors and touch-evoked FOS expression in the spinal dorsal horn at day 3, but not days 5 and 10, post-spinal nerve ligation when compared with sham-operated controls. These results indicate the presence of nerve injury-induced behavioral hypersensitivity associated with nerve injury-induced central sensitization. Further, the results demonstrate the novel concept that once initiated, maintenance of nerve injury-induced central sensitization in the spinal dorsal horn requires descending pain facilitation mechanisms arising from the rostral ventromedial medulla.

Animals↗

[Flow cytometric analysis of the garlic oil effect on DNA content of cancer cell cycle].

Flow cytometry (FCM) is a new technique developed in the recent decade. This technique may measure DNA content of 5000 cells per second and trace the dynamic changes in cell proliferation cycle and offer a hint for designing clinical treatment protocol, monitor prognosis and elucidate the mechanisms of antitumor drugs. The authors previous studies showed significant effect of garlic oil on prolongation of life expectancy and inhibition of tumor growth in mice. Using FCM the authors analysed the effect of garlic oil on cell cycle in S180 tumor cells, 2-6 hrs after single administration or multiple administration the cell number in S phase rapidly decreased, in G1 phase increased. This suggests garlic oil may blockade cells to progress from G1 phase to S phase and result in accumulation of cells in G1 phase and directly inhibit the synthesis of DNA and the cell cycle. Theoretical basis for clinical application was offered and some aspects of antitumor mechanism of garlic oil were elucidated.

Allyl Compounds↗

[Studies on sensor for L-ascorbic acid using biotissue slice].

Bioselective membrane electrode for L-ascorbic acid has been made with tissue slices. It is made from porcine liver tissue slice covering an oxygen electrode. The influence of buffer mediator, pH, temperature, antiseptics, slice thickness, etc. on the response characteristics of the electrode was examined. In the presence of copper ions, a linear relationship between dynamic response of the electrode and the logarithm of concentration of L-ascorbic acid was observed for the range of 21.14 micrograms/ml to 352.3 micrograms/ml, with a correlation coefficient of 0.9996 and the Michaelis constant of 0.8 mmol/L. The electrode has been used to determine L-ascorbic acid in drugs, the analytical results were satisfactory.

Animals↗

Circulatory effects of anisodamine on cardiopulmonary bypass.

Anisodamine, a new M-cholinergic blocker discovered in China, was employed in experimental dogs on cardiopulmonary bypass (CPB) with a view to observing its hypotensive activities. Before bypass an intravenous bolus injection of anisodamine 5 mg/kg caused a transient fall of about 20 mmHg in arterial blood pressure for 10 to 15 minutes, with an increase of about 10 mmHg in pulse pressure, indicating lowering afterload. During bypass, a continuous intravenous drip of anisodamine brought about 27 to 37 mmHg fall in perfusion pressure (compared with the control group) while the perfusion flow rate was kept constant. Beneficial effects of anisodamine were manifested, post-bypass, by enhancement of cardiac output, lack of elevation of pulmonary arterial pressure, a speedy recovery of the ST segment to normal, and a decrease of the rate-pressure product, as results of circulatory improvement and myocardial protection.

Animals↗