ABSTRACT
Objective To compare the mandibular advancement appliance(MAA) with mandibular advancement and left-leaning appliance (MALA) in the treatment of mild or moderate obstructive sleep ap-nea-hypopnea syndrome (OSAHS). Methods Twenty-two cases of mild or moderate OSAHS were treated with MAA, and 19 cases with MALA. After 1-3 months, they were examined again with Epworth score and polysonmography (PSG). Results After 1-3 months of the MAA or MALA treatment, the Epworth score was improved evidently. The apnea -hypopnea index, max apnea time, mean apnea time, oxygen desaturatian index, and the longest time of oxygen desaturation were all lowered after the treatment, and the lowest SaO2 and the mean SaO2 were higher after the treatment. The differences were all distinctive (P<0.05 or<0.01). When patients treated with MAA were compared with those treated with MALA,only the max apnea time [(35.5±6.9),(31.3±6.0) s, respectively] and the longest time of oxygen desaturation [ (41.0±18.9), (29.9±9.3) s, respectively] had significant difference. Conclusion MALA may be helpful for shortening max apnea time and the longest time of oxygen desaturation, thus MAA is an effective alternative to patients of OSAHS. Further research should be done.
ABSTRACT
AIM: To study the effect of chronic hypoxic hypercapnia on gene expression of thromboxane synthase and prostacyclin synthase in pulmonary arterioles. METHODS: Sprague-Dawley rats were randomly divided into two groups: control group and hypoxic hypercapnic group. TXS mRNA and PGI 2-S mRNA were observed in pulmonary arterioles by in situ hybridization. RESULTS:mPAP, weight ratio of right ventricle (RV) to left ventricle plus septum(LV+S), contents of TXB 2 and 6-keto-PGF1 ? in plasma and lung and TXS mRNA in pulmonary arterioles were much higher in rats of hypoxic hypercapnic group than those of control group. Differences of PGI 2-S mRNA in pulmonary arterioles were not significant in two groups. Light microscopy showed hypertrophy of vessel smooth muscle cells and vessel cavity straitness were found in hypoxic hypercapnic group. CONCLUSION: Changes of gene expressions of thromboxane synthase and prostacyclin synthase and imbalance of TXA 2/PGI 2 may play an important role in hypoxic hypercapnic pulmonary hypertension.
ABSTRACT
AIM: To study the effect of safflower injection on expression of COX-2 mRNA in chronic hypoxic hypercapnic rat pulmonary arterioles.METHODS: Sprague-Dawley rats were randomly divided into normal control group,hypoxic hypercapnic group(B),hypoxic hypercapnia+ safflower injection group(C).The concentration of TXB2 and 6-Keto-PGF1? in plasma and in lung were detected by the technique of radioimmunoassay.COX-2 mRNA was observed in arterioles from rats by the technique of in situ hybridization.RESULTS: ① Mean pulmonary arterial pressure(mPAP),weight ratio of right ventricle(RV) to left ventricle plus septum(LV+S) were much higher in B group than those in control group.No significant difference of mean carotid arterial pressure(mCAP) was observed in three groups.② The concentration of TXB2 and the ratio of TXB2/6-keto-PGF1? were significantly higher in B group than those in control group.③ Light microscopy showed that vessel wall area/total area,the density of medial smooth muscle cells and the thickness of medial smooth cell layer were significantly higher in B group than those in control group.Electron microscopy showed proliferation of medial smooth muscle cells and collagenous fibers in pulmonary arterioles in B group.Safflower injection reversed the changes mentioned above.④ Expression of COX-2 mRNA in pulmonary arterioles was much higher in C group than those in B group.Differences of COX-1 mRNA in pulmonary arterioles were not significant between these two groups.CONCLUSION: Safflower injection increases the expression of COX-2 mRNA in chronic hypoxic hypercapnic rat pulmonary arterioles,indicating an important mechanism that safflower injection inhibits the formation of hypoxic hypercapnia pulmonary hypertension and pulmonary vessel remodeling.