48 research outputs found
Serological assessment of gastric mucosal atrophy in gastric cancer
<p>Abstract</p> <p>Background</p> <p>Non-invasive tools for gastric cancer screening and diagnosis are lacking. Serological testing with the detection of pepsinogen 1 (PG1), pepsinogen 2 (PG2) and gastrin 17 (G17) offers the possibility to detect preneoplastic gastric mucosal conditions. Aim of this study was to assess the performance of these serological tests in the presence of gastric neoplasia.</p> <p>Methods</p> <p>Histological and serological samples of 118 patients with gastric cancer have been assessed for tumor specific characteristics (Laurén type, localisation), degree of mucosal abnormalities (intestinal metaplasia, atrophy) and serological parameters (PG1, PG2, PG1/2-ratio, G17, <it>H. pylori </it>IgG, CagA status). Association of the general factors to the different serological values have been statistically analyzed.</p> <p>Results</p> <p>Patients with intestinal type gastric cancer had lower PG1 levels and a lower PG1/2-ratio compared to those with diffuse type cancer (<it>p </it>= 0.003). The serum levels of PG2 itself and G17 were not significantly altered. <it>H. pylori </it>infection in general had no influence on the levels of PG1, PG2 and G17 in the serum of gastric cancer patients. There was a trend towards lower PG1 levels in case of positive CagA-status (<it>p </it>= 0.058). The degree of both intestinal metaplasia and atrophy correlated inversely with serum levels for PG1 and the PG1/2-ratio (p < 0.01). Laurén-specific analysis revealed that this is only true for intestinal type tumors. Univariate ANOVA revealed atrophy and CagA-status as the only independent factors for low PG1 and a low PG1/2-ratio.</p> <p>Conclusions</p> <p>Glandular atrophy and a positive CagA status are determinant factors for decreased pepsinogen 1 levels in the serum of patients with gastric cancer. The serological assessment of gastric atrophy by analysis of serum pepsinogen is only adequate for patients with intestinal type cancer.</p
Vestibular evoked myogenic potential: recording methods in humans and guinea pigs
O potencial miogênico evocado vestibular (VEMP) é um teste clÃnico que avalia a função vestibular através de um reflexo vestÃbulo-cervical inibitório captado nos músculos do corpo em resposta à estimulação acústica de alta intensidade.
OBJETIVO: Verificar e analisar os diversos métodos de registro dos potenciais miogênicos evocados vestibulares no homem e em cobaias.
MATERIAL E MÉTODO: Realizou-se busca eletrônica nas bases de dados MEDLINE, LILACS, SCIELO e COCHRANE.
RESULTADOS: Foram verificadas divergências quanto à s formas de registro dos potenciais miogênicos evocados vestibulares, relacionadas com os seguintes fatores: posição do paciente no momento do registro, tipo de estÃmulo sonoro utilizado (clicks ou tone bursts), parâmetros para a promediação dos estÃmulos (intensidade, freqüência, tempo de apresentação, filtros, ganho de amplificação das respostas e janelas para captação dos estÃmulos), tipo de fone utilizado e forma de apresentação dos estÃmulos (monoaural ou binaural, ipsi ou contralateral).
CONCLUSÃO: Não existe consenso na literatura quanto ao melhor método de registro dos potenciais evocados miogênicos vestibulares, havendo necessidade de pesquisas mais especÃficas para comparação entre estes registros e a definição de um modelo padrão para a utilização na prática clÃnica
Binaural interaction of bone-conducted auditory brainstem responses in children with congenital atresia of the external auditory canal
Bilateral bone-conducted auditory brainstem responses (BC-ABRs) were recorded in children with atresia of the external auditory canal bilaterally (AECB) in order to compare the response characteristics to normal hearing adults. The binaural interaction component (BIC) of the ABR occurs when the sum of the monaural-evoked ABR amplitudes are different in amplitude when compared to the binaural-evoked ABR amplitude. Previous electrophysiological work from our lab has shown that children with AECB lateralize bone-conducted (BC) sound. Furthermore, we have found in normal-hearing adults that BICs exist using BC clicks. In adults, BC-BIC occurred in the latency region corresponding to waves IV-VI, whereas for children with AECB corresponding peak latencies occurred earlier. Same as normal-hearing adults, BC-ABR IV-V complex peak amplitudes for sum of the BC-monaural right and BC-monaural left ears were different from binaural response amplitude. Individual peak latencies were similar in children with AECB when compared to normal-hearing adults except for shorter latencies for BIC. These results indicate that: (1) BC-BI is present in children with AECB as well as normal-hearing adults; (2) the gross response properties of BIC are similar in children with AECB and normal-hearing adults; (3) fitting of a bilateral BC hearing aid might be a feasible method to optimize binaural hearing and sound lateralization
Environmental Sound Perception in Patients with Cochlear Implants Compared with That in Patients with Auditory Nerve Diseases (Auditory Neuropathy) and Cortical Deafness
Epidemiologic study of pulmonary tuberculosis in golestan province, iran 2007-2016
Background and purpose: Despite appropriate prevention and therapeutic activities in recent years, Pulmonary Tuberculosis (TB) is still one of the top ten causes of mortality in the world. The purpose of this study was to analyze the distribution of pulmonary tuberculosis in cities of Golestan province, Iran and identifying the major determinants of this disease. Materials and methods: from 8374 TB cases was recorded in TB Registry Program in Golestan province between 2007 and 2016 we analyzed the information of 5648 new cases. Data was analyzed in SPSS 24 and Stata 13. Mean ± SD and frequency table were applied for quantitative and qualitative variables, respectively. Results: The standardized incidence rate of TB in 100,000 population in Golestan province was 41.29 and in males and females it was 41.40 and 41.22, respectively, indicating no significant differences between them (p< 0.34). TB hazard ratio was found to be 62 higher in rural areas (p<0.001). The standardized incidence rates in urban and rural areas were 31.63 and 51.36 in 100,000 population, respectively. Ramyan and Gomishan had the highest and lowest incidence rats of TB, respectively (77.68 and 14.88 in 100,000 population, respectively). Conclusion: According to current findings, screening for TB in rural areas in Golestan province is highly recommended. Eastern regions of the province are at greater risk for TB infection due to their ethnic composition (Sistan and Baluchestan immigrants). © 2018, Mazandaran University of Medical Sciences. All rights reserved
Investigation of ΔE Effect on Vibrational Behavior of Giant Magnetostrictive Transducers
Resonant magnetostrictive transducers are used for generating vibrations in the sonic and ultrasonic range of frequency. As the mechanical properties of magnetostrictive materials change according to different operating conditions (i.e., temperature, mechanical prestress, and magnetic bias), the vibrational behavior of the transducer changes too. ΔE effect is the change in the Young modulus of the ferromagnetic material and it has to be considered as it leads to changes in the dynamics of the transducer. This paper deals with the study of such effect from both theoretical and experimental point of view. ΔE effect on behavior of the transducer based on Terfenol-D is analytically described as a function of different operating conditions focusing on effects on resonance frequency, mode shape, and moreover experimentally the quality factor. Results of resonance frequency prediction have been validated with experiments and good agreement has been seen