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91.
IntroductionTinnitus is characterized by the presence of a sound in the absence of external sound stimulus. In individuals with normal audiometry, it may be associated with auditory attention difficulty, especially in those who report high tinnitus annoyance.ObjectiveTo investigate auditory attention ability in individuals with tinnitus complaint.MethodsCross-sectional analytical observational study. We evaluated 30 volunteers with normal hearing (up to 25 dBHL): 15 with tinnitus (test group) and 15 with no complaints (control group), aged between 18-40 years. The volunteers answered the tinnitus handicap inventory questionnaire and a visual analogue scale. Subsequently, a basic audiological evaluation (meatoscopy, tonal and vocal audiometry, and imittanciometry) and psychoacoustic measures of tinnitus (loudness and pitch) were performed. To evaluate auditory attention, the following tests were performed: auditory cognitive evoked potential (P300), central auditory processing tests (dichotic digits test and speech-in-noise test) and sustained auditory attention ability test.ResultsIn the tinnitus handicap inventory, individuals with tinnitus had a mean score of 37.78 (±27.05), characterized as moderate degree. In the dichotic digits test (binaural separation), a difference was observed between the groups in both ears. Moreover, there was a difference in the speech-in-noise test in both ears (RE: p = 0.044; LE: p = 0.019), in P300 (p = 0.049) and in total sustained auditory attention ability test (p = 0.032). Also, there is a negative correlation between sustained auditory attention ability test, decrease in attentiveness and binaural integration (RE: p = 0.044; LE: p = 0.048).ConclusionsIndividuals with tinnitus had a poorer performance compared to the control group regarding auditory attention ability. Therefore, it is inferred that tinnitus is associated with poor performance in selective and sustained auditory attention in the assessed volunteers. These aspects should be considered for the management of patients with tinnitus.  相似文献   
92.
IntroductionCartilage is the grafting material of choice for certain disorders of the middle ear. The indications for its routine use remain controversial due to the possible detrimental effect on post-operative hearing.ObjectiveThe present study was carried out to report a personal experience with “tragal cartilage shield” tympanoplasty to compare the results, in terms of graft uptake and hearing improvement, of endoscopic cartilage shield technique using either partial thickness or full thickness tragal cartilage for type 1 tympanoplasty and to highlight the tips for single-handed endoscopic ear surgery.MethodsFifty patients with safe chronic suppurative otitis media, assisted at out-patient department from February 2014 to September 2015 were selected. They were randomly allocated into two groups, 25 patients were included in group A where a full thickness tragal cartilage was used and 25 patients included in group B where a partial thickness tragal cartilage was used. Audiometry was performed 2 months after the surgery in all cases and the patients were followed for one year.ResultsOut of the total of 50 patients 39 (78%) had a successful graft take up, amongst these 22 belonged to group A and 17 belonged to the group B. The hearing improvement was similar in both groups.ConclusionThis study reveals that endoscopic tragal cartilage shield tympanoplasty is a reliable technique; with a high degree of graft take and good hearing results, irrespective of the thickness. Furthermore, the tragal cartilage is easily accessible, adaptable, resistant to resorption and single-handed endoscopic ear surgery is minimally invasive, sutureless and provides a panoramic view of the middle ear.  相似文献   
93.
IntroductionObstrutive sleep apnea syndrome is characterized by repeated episodes of upper airway obstruction, associated with intermittent hypoxia and hypercapnia, and the main risk factor in childhood is adenotonsillar hypertrophy. The lymphocytes in these structures are responsible for local and systemic immune responses.ObjectiveVerify the levels of the inflammatory markers, IL-1β, IL-4, IL-6, IL-8, IL-10, IL-15, TNF-α, CRP and α1-GP, in the tonsils of children with and without obstructive sleep apnea syndrome.MethodsThis cross-sectional prospective study included 34 children with complains of snoring, difficulty breathing during sleep or recurrent tonsillitis. Patients underwent to a complete otorhinolaryngological examination, nasal endoscopy and polysomnography and were divided into two groups with 17 children each: obstructive sleep apnea syndrome group and control group. All underwent an adenotonsillectomy. Cytokines were measured in the collected tonsils (ELISA and Multiplex methods).ResultsStatistically significant increasing were observed between IL-8 and IL-10 cytokines of patients with obstructive sleep apnea when compared to the control group; also between c-reactive protein and α1-GP of the tonsils cortical region in children with obstructive sleep apnea syndrome when compared with the medullary region. There were no statistically significant differences for the remaining inflammatory mediators.ConclusionAfter the analysis of the levels of pro and anti-inflammatory markers (IL-1β, IL-4, IL-6, IL-8, IL-10, Il-15, TNF-α, CRP, α1-GP) in the tonsils, we observed higher levels of markers IL-8 and IL-10 in pediatric patients with obstructive sleep apnea syndrome.  相似文献   
94.
IntroductionDeficient auditory processing can cause problems with speech perception and affect the development and evolution of reading skills. The efferent auditory pathway has an important role in normal auditory system functions like speech-in-noise perception, but there is still no general agreement on this.ObjectiveTo study the performance of the efferent auditory system in a group of children with reading impairment in comparison with normal reading and evaluation of its relationship with speech-in-noise perception.MethodsA total of 53 children between the ages of 8–12 years were selected for the study of which 27 were with reading impairment and 26 were normal reading children. Transient evoked otoacoustic emissions suppression and auditory recognition of words-in-noise test were performed for all the children.ResultsThe average amplitude of transient evoked otoacoustic emissions suppression showed a significant difference between the two groups in the right (p = 0.004) and in the left ear (p = 0.028). Assessment of the relationship between transient evoked otoacoustic emissions suppression and monaural auditory recognition of words-in-noise scores showed a significant moderate negative relationship only in the right ear (p = 0.034, r = −0.41) of the normal reading children. Binaural auditory recognition of words-in-noise scores were significantly correlated with the amplitude of transient evoked otoacoustic emissions suppression in the right ear (p < 0.001, r = −0.75) and in the left ear (p < 0.001, r = −0.64) of normal reading children. In the reading impaired group, ?a weaker correlation was observed between binaural auditory recognition of words-in-noise scores and transient evoked otoacoustic emissions suppression in the right (p = 0.003, r = −0.55) and in the left ear (p = 0.012, r = −0.47).ConclusionsTransient evoked otoacoustic emissions suppression pattern in the reading impaired group was different compared with normal reading children, and this difference could be related to efferent system performance. Words-in-noise scores in children with impaired reading were lower than in normal reading children. In addition, a relationship was found between transient evoked otoacoustic emissions suppression and words-in-noise scores in both normal and impaired reading children.  相似文献   
95.
目的:探讨 circRNA_001569 通过 miR-145/HBXIP 轴在乳腺癌细胞增殖、侵袭、迁移中发挥的作用。方法:收集2016年1月至2019年1月期间衡水市人民医院收治的30例乳腺癌患者的癌组织和癌旁组织。qPCR检测circRNA_001569在乳腺癌组织、癌旁组织以及细胞系中的表达。生物信息学工具预测miR-145的靶基因,RNA免疫沉淀(RNA immunoprecipitation,RIP)和双荧光素酶报告基因实验检测 miR-145 或靶基因之间的相互作用 ;向乳 腺 癌 MDA-MB-231 和 MCF-7细胞中转染si-circRNA_001569、miR-145 mimics或miR-145 inhibitor,建立基因过表达或沉默的细胞模型,qPCR和Western blotting分别检测转染对相关基因和蛋白表达的影响,CCK-8法、Transwell实验检测转染对细胞增殖、侵袭和迁移的影响。结果:在乳腺癌组织和乳腺癌细胞中,circRNA_001569 和 HBXIP 均呈高表达、miR-145 呈低表达。RIP 分析和双荧光素酶实验证实了 miR-145 与circRNA_001569和HBXIP之间的靶向关系;circRNA_001569或HBXIP过表达促进MDA-MB-231和MCF-7细胞的增殖、侵袭和迁移(均 P<0.01),而 miR-145 过表达起相反的作用(均 P<0.01)。结论:circRNA_001569 可能通过下调 miR-145 的表达、上调HBXIP的表达从而促进乳腺癌细胞的增殖、侵袭和迁移。  相似文献   
96.
 目的:探究沉默Jagged 1 (JAG1)基因对人乳腺癌MDA-MB-231细胞增殖和凋亡的影响及其分子生物学机制。方法:
用已构建的pRS-JAG1重组质粒转染人乳腺癌MDA-MB-231细胞, 采用Western blotting方法检测重组质粒对JAG1蛋白表达的影响;MTT比色法测定沉默JAG1对细胞生长的抑制情况;流式细胞术检测细胞周期和细胞凋亡;蛋白印记分析细胞周期蛋白1(cyclin D1)、p21CIP1/WAF1、p27KIP1、p-Rb、Bcl-2、Bax、Bcl-xL和cleaved caspase-3蛋白水平的变化。结果:Western blotting结果证实重组质粒可在72h内有效抑制JAG1蛋白表达;人乳腺癌MDA-MB-231细胞JAG1被沉默后,细胞的生长速度明显减慢,细胞明显阻滞于G 0/G 1期,细胞凋亡率显著升高(P<0.05),cyclin D1、p-Rb、Bcl-2和Bcl-xL蛋白水平被下调(P<0.05),而p21CIP1/WAF1、p27KIP1、Bax和cleaved caspase-3的蛋白水平显著升高(P<0.05)。结论:沉默JAG1可有效抑制人乳腺癌MDA-MB-231细胞增殖,并诱导其凋亡。本研究为以JAG1为分子靶点的三阴乳腺癌治疗提供实验依据。  相似文献   
97.
B7-H1是一种重要的负性共刺激分子,在肿瘤免疫逃逸中发挥重要作用,而微小RNA具有直接的转录后调控作用。本文研究miR-570对B7-H1表达的调控作用。首先将miR-570及其抑制剂anti-miR-570分别转染B7-H1表达阳性的人胃癌细胞SGC-7901和B7-H1表达阴性的人乳腺癌细胞MDA-MB-435,以流式细胞术检测B7-H1分子表达情况;然后构建pcDNA/B7-H1表达质粒与miR-570共转染CHO细胞,以流式细胞术检测CHO细胞上B7-H1分子的表达情况;最后分别构建含B7-H1基因3-UTR片段和含miR-570作用靶点序列的荧光素酶表达载体与miR-570共转染CHO细胞,用双荧光素酶报告系统检测荧光素酶活性。结果显示miR-570能显著抑制SGC-7901细胞和B7-H1基因转染细胞膜上B7-H1蛋白的表达,并能显著抑制荧光素酶表达载体表达的荧光素酶蛋白,而且anti-miR-570能上调MDA-MB-435细胞上B7-H1表达。本研究证明miR-570能显著抑制B7-H1蛋白表达,为通过抑制B7-H1信号通路以增强机体抗肿瘤免疫力的治疗途径奠定了基础。  相似文献   
98.
目的:探讨小檗碱对人乳腺癌细胞MDA-MB-231体外生长的影响及其与PPAR-y受体的关系.方法:采用噻唑蓝(MTT)法检测小檗碱对MDA-MB-231细胞的生长抑制效应;TUNEL法检测细胞凋亡;联合PPAR-γ拮抗剂GW9662,分析小檗碱对MDA-MB-231细胞增殖的影响与PPARγ受体的关系.结果:小檗碱呈量-效和时-效关系抑制MDA-MB-231细胞生长,24 h的半数抑制浓度(IC50)为0.21μmol/L;小檗碱诱导MDA-MB-231细胞凋亡作用随药物浓度的增加而增强;PPARγ受体拮抗剂不能逆转小檗碱对细胞增殖的抑制作用.结论:小檗碱可明显抑制MDA-MB-231细胞生长并诱导其凋亡,但其作用不通过PPAR受体介导.  相似文献   
99.
IntroductionBurnt sugarcane harvesting requires intense physical exertion in an environment of high temperature and exposure to particulate matter.ObjectiveTo evaluate the effects of burnt sugarcane harvesting on rhinitis symptoms and inflammatory markers in sugarcane workers.MethodsA total of 32 male sugarcane workers were evaluated with questionnaire for rhinitis symptoms, and for inflammatory markers on peripheral blood and nasal lavage, in the non-harvesting, and 3 and 6 months into the sugarcane harvesting period. Weather data and particulate matter fine concentrations were measured in the same day.ResultsThe particulate matter concentrations in sugarcane harvesting were 27 (23–33 μg/m3), 112 (96–122 μg/m3), and 63 (17–263 μg/m3); 24 h temperatures were 32.6 (25.4–37.4 °C), 32.3 (26.7–36.7 °C) and 29.7 (24.1–34.0 °C) and relative humidities were 45.4 (35.0–59.7%), 47.9 (39.1–63.0%), and 59.9 (34.7–63.2%) in the non-harvesting period, three and 6 months of the harvesting period. The age was 37.4 ± 10.9 years. The prevalence of rhinitis symptoms was significantly higher at 3 months of the harvesting period (53.4%), compared to non-harvesting period (26.7%; p = 0.039) and at 6 months into the harvesting period (20%; p = 0.006). Concentrations of interleukin 6 (IL-6) in nasal lavage increased after 3 months of the harvesting period compared to the non-harvesting period (p = 0.012). The presence of rhinitis symptoms, after 3 months of the harvesting period, was directly associated with blood eosinophils and inversely associated with neutrophils.ConclusionsAfter 3 months of work in burnt sugarcane harvesting the prevalence of rhinitis symptoms and IL-6 in nasal lavage increased. Furthermore, eosinophil counts were directly associated with the rhinitis symptoms in the period of higher concentration of particulate matter.  相似文献   
100.
IntroductionPossible associations between Zika virus infection and hearing loss were observed during the epidemic in the Americas.ObjectiveTo describe the auditory alterations, pathogenesis and recommendations for follow-up in individuals with prenatal or acquired Zika virus infection.MethodsBibliographic research conducted in March/2018–April/2019 at the main available databases. Article selection, data extraction and quality evaluation were carried out by two independent reviewers. Studies containing auditory evaluation of patients with congenital or acquired Zika virus infection; and/or hypotheses or evidences on the pathophysiology of auditory impairment associated with Zika virus; and/or recommendations on screening and follow-up of patients with auditory impairment by Zika virus were included.ResultsA total of 27 articles were selected. Sensorineural and transient hearing loss were reported in six adults with acquired Zika virus infection. Of the 962 studied children, 482 had microcephaly and 145 had diagnostic confirmation of Zika virus; 515 of the 624 children with auditory evaluation performed only screening tests with otoacoustic emissions testing and/or automated click-stimuli auditory brainstem response testing. Studies in prenatally exposed children were very heterogeneous and great variations in the frequency of altered otoacoustic emissions and automated click-stimuli auditory brainstem response occurred across the studies. Altered otoacoustic emissions varied from 0% to 75%, while altered automated click-stimuli auditory brainstem response varied from 0% to 29.2%. Sensorineural, retrocochlear or central origin impairment could not be ruled out. One study with infected mice found no microscopic damage to cochlear hair cells. Studies on the pathogenesis of auditory changes in humans are limited to hypotheses and recommendations still include points of controversy.ConclusionThe available data are still insufficient to understand the full spectrum of the involvement of the auditory organs by Zika virus, the pathogenesis of this involvement or even to confirm the causal association between auditory involvement and virus infection. The screening and follow-up recommendations still present points of controversy.  相似文献   
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