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L Y Xing

Publications and source records attributed to L Y Xing.

6 recordsLinked to original sources

[Decrease of calcitonin gene-related peptide release from mesenteric arterial bed in diabetic rats and effect of nitric oxide].

Our previous work has shown that endotoxin triggers the release of calcitonin gene-related peptide (CGRP) from the mesenteric arterial bed, which is partially mediated by nitric oxide. In the present study, the changes of endotoxin-induced CGRP release from the isolated mesenteric arterial bed and the CGRP mRNA levels in dorsal root ganglia (DRG) of diabetic rats were studied in relation to the effect of nitric oxide. CGRP level in perfusate and the steady-state level of mRNA for CGRP in DRG were determined by RIA and semi-quantitatively by RT-PCR. The results showed that endotoxin (1-25 micrograms/ml) accumulated in perfusate caused concentration-dependent release of CGRP, which was significantly decreased in mesenteric arterial bed of diabetic rats. As compared with age-related control, the endotoxin (10 and 25 micrograms/ml) -induced CGRP release in diabetic rats was attenuated by 27% and 40%, respectively. L-NAME, an inhibitor of nitric oxide synthase, inhibited the effect of endotoxin in dose of 10 and 25 micrograms/ml by 23% and 46%, respectively against the control rats. However, there was no inhibitory effect of L-NAME on endotoxin-induced CGRP release in diabetic rats. The CGRP mRNA level in DRG showed no significant difference between the two groups. These results indicate that the response of the isolated mesenteric arterial bed to endotoxin-induced CGRP release in diabetic rats is significantly lower than that in control. The mechanism, at least in part, is due to a decrease of nitric oxide mediated release of CGRP, rather than a decrease of CGRP gene expression.

Animals↗

Expression of calcitonin gene-related peptide (CGRP) mRNA in rat lymphocytes.

We recently found that calcitonin gene-related peptide (CGRP)-like immunoreactivity was present in lymphocytes of rat thymus and lymph node. In order to investigate whether these cells were capable of synthesizing CGRP, CGRP mRNA of rat dorsal root ganglia, thymocytes and mesenteric lymph node lymphocytes were determined by reverse transcription and polymerase chain reaction (RT-PCR) utilizing synthetic oligonucleotides bracketing a portion of the calcitonin/CGRP gene. A discrete band of the expected size of 90 base pairs was found in the dorsal root ganglia (positive control), and in both thymocytes and mesenteric lymph node lymphocytes. These data strongly suggest that CGRP is not only an important neuropeptide, but it is also synthesized in lymphocytes of both thymus and lymph nodes, which is identical to that in sensory neurons. CGRP from lymphocytes may act as an immunomodulator and serve as a common ligand in immune and nervous systems.

Animals↗

[In vitro analysis of cross immunoreaction between CGRP and endotoxin in CGRP radioimmunoassay].

In the present study, the effect of endotoxin on the radioimmunoassay of calcitonin gene-related peptide (CGRP) was investigated by method of radioimmunoassay. The results showed a competitive combination of endotoxin at high-concentrations (higher than 5 micrograms/ml) with multiclonal antibody of CGRP, and the cross immunoreaction ratio between CGRP and endotoxin was 5.6 x 10(-6). The mixed endotoxin in samples was effectively cleared through C18 column purification. The data indicated that endotoxin interfered CGRP radioimmunoassay in vitro at high concentrations. The influence of endotoxin on CGRP radioimmunoassay can be avoided through C18 column purification for the endotoxin-containing samples.

Animals↗

Corn and wheat-flour consumption and mortality from esophageal cancer in Shanxi, China.

In order to identify factors that may explain the great variation in mortality from esophageal cancer in Shanxi Province, China, an ecological study was carried out in 21 communes in that province. Mortality data were obtained from the registration records of the population of 148,928 during 1983 to 1988, which provided 744,640 person-years of observation. The data regarding average consumption of each kind of grain, potatoes and sweet potatoes were from food allocation records. The data regarding consumption of meat, eggs, fruit, vegetables and the data regarding alcohol drinking were from interviews. The concentrations of nitrite and of nitrate in pickled vegetables and in drinking water were measured. A significant positive relation was found between mortality rate and the consumption of dietary corn and wheat flour. Also, a significant inverse relation was found between the mortality rate and the dietary sorghum and millet level. The age- and sex-adjusted mortality-rate ratio of esophageal cancer for residents in the third and highest quartiles of corn- and wheat-flour consumption are 1.4 (95% CI: 1.1-2.0) and 3.2 (2.5-4.2), respectively, compared with those in the lowest quartile. Other factors studied did not contribute to the great variation in esophageal cancer mortality in the areas studied.

Adult↗

[Brenner tumor of the ovary--a clinicopathological report of 5 cases].

This paper reports 5 cases of Brenner tumor of the ovary treated in our hospital from 1967 to 1985. The patients' mean age was 54.6 years. Three lesions were solid, 1 cystic and the other occurred on the wall of a borderline malignant mucinous cystadenoma. All the 5 cases were benign by pathology. The clinical symptoms were abdominal pain in 3 cases, 2 of which had a torsion of the tumor pedicle, abdominal mass in 1 and abdominal swelling in the other. All the cases possessed the same feature that the tumor was composed of both hyperplastic epithelial nest and fibrous stroma. In histology, there were 3 transitional epithelial cell types and 2 basal cell-like types. Histogenesis of the Brenner tumor, according to the authors' observation, was shown by: 1. The epithelial cell nests of Brenner tumor were similar to the transitional epithelium of the urinary tract in 60% of these cases; basal-like cell in the early stage of differentiation comprised 40%, 2. In 80% of patients, there was observed, in the cell nuclei, a longitudinal groove, which resembled the cells of Walthard cell nests; 3. The transitional epithelial cells were found in the cyst wall of 1 polycystic tumor; another case was complicated with mucinous cystadenoma and there was no sharp demarcation between the two tumors under microscope. It suggests that the histogenesis imply that the Brenner tumor may arise from the coelomic epithelium of para-mesonephros. The authors also believe that certain Brenner tumors have endocrine activity, but the relation between which and the tumor stroma luteinization should be further studied.

Adult↗