Biomedical subjects

B Qi

Publications and source records attributed to B Qi.

29 records · Page 2Linked to original sources

PubMed1996

Lung hypoplasia and surfactant system immaturity induced in the fetal rat by prenatal exposure to nitrofen.

We studied the biochemical maturity of the lungs of fetuses born to rats exposed to nitrofen on day 9.5 of gestation. In comparison with controls, nitrofen-treated fetuses had pulmonary hypoplasia (decreased lung/body weight), lung hypocellularity (low DNA content) and cellular atrophy (low protein/DNA and phospholipid/DNA) on gestational days 19 and 21. Treated animals with congenital diaphragmatic hernia (CDH) also had cell atrophy and surfactant immaturity (decreased disaturated phosphatidylcholine/DNA) near term. Our data demonstrate that nitrofen causes lung hypoplasia and some degree of surfactant system immaturity that is particularly prominent in fetuses with CDH.

Animals↗

PubMed1996

[Effects of diaphragmatic plication in the antireflux barrier in rats].

INTRODUCTION: There is increasing evidence of frequent occurrence of gastroesophageal reflux (GER) in patients surviving operations for congenital diaphragmatic hernia (CDH) and diaphragmatic eventration (DE). The murine model allows to study the behavior of the components of antireflux barrier. AIM: To study the changes introduced in esophageal-gastric junction by DE due to cervical transection of the left phrenic nerve and subsequent plication of the paralyzed diaphragm. MATERIAL AND METHODS: Adult male Wistar rats were divided into two groups: in one we measured the pressure conditions before and after phrenic nerve section (PNS) and in the other we evaluated such conditions in PNS rats before and after diaphragmatic plication (DP). RESULTS: Phrenic transection significantly lowered inspiratory pressure gradient (IPG), (2.79 +/- 1.05 vs 4.43 +/- 1.03, p < 0.05), without changes in expiratory pressure gradient (EPG) (0.31 +/- 1.03 vs 0.25 +/- 1, p > 0.05), or lower esophageal sphincter pressure (LESP) (20.88 +/- 7.73 vs 15.88 +/- 9.25, p > 0.05). Plication of the diaphragm reestablished normal IPG (4.04 +/- 0.75 vs 2.58 +/- 0.51, p < 0.05) while increased EPG (1 +/- 0.75 vs -0.32 +/- 1.05, p < 0.05) and decreased LESP (10.59 +/- 5.74 vs 17.15 +/- 5.59, p < 0.05). CONCLUSION: Paralyzed diaphragmatic eventration lowered inspiratory gradient pressure; diaphragmatic plication reestablished this gradient, but decreased LESP and increased expiratory gradient pressure. These modifications may contribute to induce GER.

Animals↗

PubMed1996

[Surgical treatment of ventricular septal defect complicated by pulmonary hypertension at high altitude].

103 patients (52 males, 51 females) suffered from ventricular septal defect associated with pulmonary hypertension were operated on under sardiopulmonary bypass from 1981-1995 at high altitude. The age of the patients ranged from 2 to 29 years. The ratio of pulmonary systemic arterial pressure was more than 0.91 (0.91 to 1.21). The defects were closed by using dacron patch. The operative mortality was 4.8% among the survivals. 98 patients were followed up for a period from 3 months to 3 years (mean 2.4 years). Excellent results were observed in 93 patients, and good in 4. There was a late death. On account of the improvement in surgical technique, myocardial protection and postoperative care, the result of operation was improved markedly.

Adolescent↗

PubMed1995

Effects of taurine on depletion of erythrocyte membrane Na-K ATPase activity due to ozone exposure or cholesterol enrichment.

The objective of this study was to investigate the interrelationship between taurine and erythrocyte-membrane Na-K ATPase activity. A comparison was conducted to test whether taurine or uric acid (a water-soluble scavenger of free radicals) prevents or recovers the depletion in membrane ouabain-sensitive Na-K ATPase activity resulting from ozone exposure or cholesterol enrichment of the erythrocyte membrane. A depletion of 44% and 27% in ouabain-sensitive Na-K ATPase activity was respectively caused by ozone exposure and cholesterol enrichment. Taurine as well as uric acid partially prevented the activity loss from ozone exposure. In addition, taurine at high concentrations (from 1.5 to 4.5 mM) restored the depletion of erythrocyte-membrane Na-K ATPase activity due to ozone exposure and prevented the depletion of the enzyme activity due to cholesterol enrichment. In contrast, although the same high concentrations were used, uric acid failed to show either of the above effects. These results suggest that taurine acts (1.5-4.5 mM) polyvalently as not only an antioxidizing agent but also as a membrane stabilizer to maintain the functions of membrane Na-K ATPase, a membrane-bound protein.

Adult↗

PubMed1992

Immunological demonstration of a unique 3,4-dihydroxyphenylacetate 2,3-dioxygenase in soil Arthrobacter strains.

Many bacteria biosynthesize 3,4-dihydroxyphenylacetate 2,3-dioxygenases for growth on aromatic acids, but gram-negative organisms have been most extensively studied. A gram-positive strain containing 2,3-dioxygenase activity was identified as Arthrobacter strain Mn-1. The 2,3-dioxygenase from strain Mn-1 was purified to homogeneity by fast protein liquid chromatography with a Mono Q anion-exchange column. Rabbit polyclonal antidioxygenase antibodies were prepared. Ouchterlony double-diffusion and Western blotting (immunoblotting) protocols were used to probe the distribution of the Mn-1 dioxygenase antigen in soil bacteria. Fourteen 2,3-dioxygenase-containing Bacillus and Pseudomonas strains did not contain immunologically cross-reactive proteins. Six of eight Arthrobacter strains contained 2,3-dioxygenase activity, and all of them produced cross-reactive proteins. The data presented here suggest that a unique type of dioxygenase is geographically widespread but is taxonomically confined to Arthrobacter soil bacteria.

Amino Acids↗

PubMed1990