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IntroductionThe prevalence of middle ear disease and its risk factors have been the subject of multiple studies. High prevalence of middle ear disease has been described among North American natives, especially chronic otitis media. Such studies have not been carried out in South America.ObjectiveTo describe the prevalence of middle ear pathology and risk factors in native schoolchildren from southern Chile who belong to the Mapuche ethnic group, as well as the impact of socio-economic and demographic changes after 14 years of development.Material and methodsTwo otologic evaluations with an interval of 14 years were performed in schoolchildren with a percentage of indigenous population above 85%. Socioeconomic and demographic data were collected from national official statistical data.ResultsA total of 1067 schoolchildren were examined. Many described risk factors for ear pathology were found. An overall prevalence of 0.19% for tympanic membrane perforation, 5.6% for pars tensa retraction pockets, 1.5% for pars flaccida retraction pockets and 11.1% of otitis media with effusion was found. There were several socioeconomic improvements after 14 years. The difference between the prevalence of symptoms and the presence of otitis media with effusion was statistically significant (p < 0.001).ConclusionsDespite the presence of several risk factors for middle ear disease, this study population showed a low prevalence of middle ear disease. The ethnic-racial factor seems to be a protective factor.  相似文献   
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The aim of the present study was to evaluate vestibular nerve involvement in patients with Bell’s palsy with ocular and cervical vestibular evoked myogenic potentials (oVEMP and cVEMP). Ten patients who were diagnosed with Bell’s palsy and ten healthy controls were included. All patients underwent VEMP recordings within 6 days after their initial presentation. Patients with Bell’s palsy had greater oVEMP asymmetry ratio comparing to healthy controls (?38.4 ± 28.7 % vs ?1.3 ± 19.3 %, p = 0.005). As well N10 latencies of the oVEMP response were prolonged comparing to healthy controls (11.575 vs 9.72 ms). There was no difference in cVEMP asymmetry ratio or latencies between groups. We found no correlation between House–Brackmann grading scale and oVEMP asymmetry ratio (r = 0.003, p = 0.994). There are three possible explanations for increased oVEMP amplitudes on the affected side: (1) oVEMP response on the ipsilateral eye could be contaminated by facial nerve activity (blink reflex); (2) the amplitude of N10-P33 could be affected through the stapedial reflex; and (3) increased oVEMP amplitude could be the consequence of the vestibular nerve dysfunction itself, with prolonged latencies of the N10 oVEMP further supporting this explanation. The results of this study indicate possible involvement of the superior branch of the vestibular nerve in patients with Bell’s palsy.  相似文献   
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Aims

To investigate early alterations on bone mineral density (BMD) and RANK, RANKL and OPG mRNA expression in peripheral blood leukocytes (PBL) in children and adolescents with type 1 diabetes (T1D) and the relationship with glycemic control and bone biomarkers.

Methods

This cross-sectional study included 75 children and adolescents with T1D and 100 individuals without diabetes (normoglycemic–NG) aged 6–20 years old. T1D individuals were considered to have good (T1DG) or poor (T1DP) glycemic control according to the values of HbA1c. Phosphorus, magnesium, total and ionized calcium, osteocalcin, alkaline phosphatase and tartaric-resistant acid phosphatase (TRAP) values were determined in blood samples. BMD was measured by DEXA. RANK, RANKL and OPG mRNA expression was measured in PBL by real-time PCR.

Results

Osteocalcin values were decreased in diabetic groups in comparison to NG group (p < 0.05), and a negative correlation with both serum glucose (r = −0.265, p < 0.01) and Hb1Ac (r = −0.252, p < 0.01) in T1D group was found. BMD was lower in diabetic groups in comparison with NG group (p < 0.05) and a negative correlation was observed between BMD and both serum glucose (r = −0.357, p < 0.01) and HbA1c (r = −0.351, p < 0.01) in T1D group. OPG mRNA expression was significantly increased in T1D and T1DP groups in comparison with NG group (p < 0.05). In conclusion, children and adolescents with early onset T1D presented low bone mineral density associated to unsatisfactory glycemic control, increased OPG mRNA expression and low osteocalcin concentration.  相似文献   
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