ABSTRACT
Objective To investigate the auditory features in patients with severe obstructive sleep apnea hy-popnea syndrome(OSAHS) and the effects of continuous positive airway pressure (CPAP) on auditory functions . Methods Pure tone audiometry thresholds ,auditory brainstem responses (ABR) and distortion product otoacoustic emissions(DPOAE) were performed in three groups with 12 observed objects in each group ,which were the OS-AHS group(before and after treatment of CPAP) ,the simple snoring group and the normal control group .Results In the OSAHS group ,the high frequency auditory thresholds(at 8000 Hz) were greatly higher and the amplitudes of DPOAE reduced ;the detection rates of DPOAE were obviously declined .The peak latencies of Ⅰ ,Ⅲ and Ⅴ , and interpeak latencies of Ⅲ - Ⅴ andⅠ - Ⅴ were longer than those of in the other two groups .The differences were statistically significant(P<0 .05) .The differences of the interpeak latencies of Ⅰ - Ⅲ ,common pure tone au-ditory thresholds (125～4000 Hz) and the thresholds of Ⅴ -wave reaction in the OSAHS group did not change sig-nificantly compared with the other two groups(P>0 .05) .The amplitudes and the detection rates of DPOAEs (0 .5～8 kHz) increased after treatment with CPAP .The differences were statistically significant except the amplitudes of 500 ,750 and 1500 Hz (P<0 .05) .Pure tone audiometry and ABRs did not changed significantly after treatment with CPAP (P> 0 .05) .Conclusion The auditory functions of patients diagnosed with severe OSAHS were im-paired .Treatments with CPAP can partly improve the patients' auditory functions .
ABSTRACT
AIM: To study the effects of vitamins on vascular activity elements in rabbits with atherosclerosis risk factors to determine whether vitamins have a role in preventing atherosclerosis. METHODS: 26 male Chinese rabbits were randomly divided into 3 groups. The first group was fed with normal feed as control group (n=6) .The other two groups were fed with normal feed plus cholesterol, lard and methionine as model group (n=10) and vitamin treatment group (n=10) respectively. In addition, the vitamin group was given multi-vitamin daily by gastrogavage. The experiment lasted for 8 wk. The vascular activity elements of the three groups were detected by radioimmunoassay and nitrate reductase respectively ,and the aorta pathological sample was prepared. RESULTS: In model group, the levels of plasma endothelin and thromboxane B 2/6-keto-prostaglandin F l? were significantly increased compared with control group, but serum nitric oxide showed no obvious changes between both groups. In vitamin group, the levels of plasma endothelin and thromboxane B 2 were significantly decreased, and the levels of 6-keto-prostaglandin F1? and nitric oxide were significantly increased compared with model group. In model group, there were significant pathological lesions, but the lesion was decreased by vitamin treatment. CONCLUTION: The vitamins supplement can alleviate or block the impairment of vascular endothelia caused by atherosclerosis risk factors, and help adjust the equilibrium of vascular activity elements. Therefore vitamins may play a positive role in preventing atherosclerosis.