ABSTRACT
The aim of this study was to investigate the effects of malnutrition, nutritional recovery, environmental stimulation and click intensity on the interpeak intervals of the waves of the Brainstem Auditory Evoked Potentials (BAEPs). The animals were divided into Well-nourished (W) and Malnourished (M) groups. At weaning, half of the M rats were submitted to nutritional recovery (R) until the test day. These groups were further subdivided into Stimulated (S) and Non-stimulated (N) rats. The BAEPs interpeak intervals I-III, I-IV and III-IV were analysed in independent groups of rats on the 18th, 22nd, 32nd and 42nd days of age. During the lactation period, stimulated rats presented shorter I-III, I-IV and III-IV interpeak intervals than Non-stimulated animals. This analysis also indicated a diet x stimulation x age interaction during the lactation period. The WN and MN groups showed a longer I-IV interval than the WS and MS groups, respectively, on the 18th and 22nd day of age, and the MN group also presented a longer I-IV interpeak interval than the WN group on the 22nd day of age. During the post-lactation period, stimulated animals showed shorter I-III and I-IV intervals than non-stimulated rats. Post hoc analysis indicated longer I-III and I-IV interpeak intervals in the MN than in the WN, RN and MS groups. Additionally, malnourished animals showed longer I-III and I-IV intervals than well-nourished and recovered rats when exposed to clicks of 90, 80 or 70 dB intensity. Malnutrition resulted in a delay of normal development of the brainstem auditory pathway indicated by the increases in the interpeak intervals of BAEPs waves, and environmental stimulation reduced these intervals, promoting faster nervous impulse transmission.
Subject(s)
Environment , Evoked Potentials, Auditory, Brain Stem/physiology , Nutrition Disorders/physiopathology , Acoustic Stimulation/methods , Animals , Animals, Newborn/physiology , Female , Lactation/physiology , Male , Rats , Rats, Wistar , WeaningABSTRACT
It has been shown that environmental stimulation may reduce the damage caused by malnutrition to morphological and behavioural parameters; however, there are no data on the effects of stimulation on the Brainstem Auditory Evoked Potentials (BAEPs). The aim of this study was to evaluate the effects of protein malnutrition, nutritional recovery and environmental stimulation on the BAEPs of the rat. On the first day of life, the animals were divided into Well-nourished (W) and Malnourished (M) groups. At weaning, half the M rats were submitted to nutritional recovery (R) until the test day. All groups were subdivided into Stimulated (S) and Non-Stimulated (N) rats. BAEPs was tested in animals exposed to clicks of 90, 80 and 70 dB of intensity. The BAEPs latencies of waves I, II, III and IV in the left ear were analysed in independent groups of rats on the 14th, 18th, 22nd, 32nd, and 42nd days of age. Statistical analysis showed diet and environmental stimulation interaction on the latencies of waves I, II, III and IV at all tested ages. WN rats showed longer latencies of waves I, II, III and IV than WS rats, and MN rats also showed longer latencies of these waves compared to WN, MS and RN at all tested ages. The results showed that malnutrition caused a delay in the latency of all BAEPs waves in rats of all ages. However, environmental stimulation reduced these latencies, reversing some damage caused by malnutrition. These data suggest that the auditory brainstem pathway is vulnerable to nutritional insults, and its structures show plasticity with environmental stimulation.
Subject(s)
Environment , Evoked Potentials, Auditory, Brain Stem/physiology , Nutrition Disorders/physiopathology , Acoustic Stimulation , Animals , Animals, Newborn/physiology , Body Weight , Female , Lactation/physiology , Rats , Rats, Wistar , Reaction Time/physiology , WeaningABSTRACT
A vectoeletronistagmografia (VENG) e otoneurologia clínica têm um ponto que deve ser sempre enfatizado: nenhum sinal clínico isolado tem um valor definitivo na localização da lesão. Por outro lado, a avaliação clínica do paciente junto com a audiometria de tronco cerebral (BERA), associada ao exame radiológico por imagem, ainda são as formas mais confiáveis de localizar uma lesão neurológica nas vias auditivas. No presente trabalho, avaliamos 05 indivíduos com diagnóstico de degeneração cerebelar autossômica dominante (ACAD), associadas ou não a lesão em tronco cerebral e vias supratentoriais. Os achados dos exames eletrofisiológicos (VENG e BERA), por imagem e estadiamento clínico são discutidos frente às várias síndromes labirínticas centrais. A tomografia computadorizada (TC) de crânio e a VENG mostraram-se alteradas em todos os pacientes, e o BERA mostrou-se alterado apenas nos pacientes com lesões do tronco. Pudemos observar vários sinais otoneurológicos como disritmia, decrutamento, dissociação cócleo-vestibular e rastreio tipo IV, entre outros. Concluímos que, apesar do estadiamento clínico BERA e TC serem mais precisos na localização da lesão, a VENG mostra alterações funcionais vestibulares centrais não identificadas na TC e bem mais precoces que o BERA, estando já presentes tanto nas doenças cerebelares isoladas como do tronco cerebral e vias supratentoriais.
Subject(s)
Humans , Male , Adult , Middle Aged , Cerebellar Diseases/diagnosis , Neurodegenerative Diseases/diagnosis , Vestibular Diseases/diagnosis , Audiometry, Evoked Response , Cerebellar Diseases/complications , Neurodegenerative Diseases/complications , Vestibular Diseases/etiology , Electronystagmography , Tomography, X-Ray ComputedABSTRACT
We report on the clinical evolution of the Brazilian family with Ramon syndrome described by de Pina-Neto et al. [1986, Am J Med Genet 25:441-443]. Three members (patients IV-2, IV-18, and IV-19) have developed pigmentary changes in the retina and paleness of the optic disk. Patient IV-18 also has developed giant hypertrophy of the labia minora that, when examined histopathologically, was found to be due to neoplastic fibroblast and epithelial proliferation caused by a fibromatous process similar to that reported in the gingivae of the patients with this syndrome. Audiologic function of patient IV-2 was normal, and no skin lesions were detected. The articular signs and symptoms show that the affected relatives developed rheumatoid arthritis, which is currently inactive in patient IV-18, whereas patient IV-2 did not develop these alterations.
Subject(s)
Fibroma/genetics , Retinal Diseases/genetics , Vulvar Neoplasms/genetics , Adolescent , Adult , Arthritis, Juvenile/genetics , Brazil , Carcinoma, Squamous Cell/genetics , Carcinoma, Squamous Cell/pathology , Cherubism/genetics , Epilepsy/genetics , Female , Fibroma/pathology , Follow-Up Studies , Gingival Hypertrophy/genetics , Growth Disorders/genetics , Humans , Hypertrichosis/genetics , Intellectual Disability/genetics , Male , Retinal Diseases/pathology , Syndrome , Vulvar Neoplasms/pathologyABSTRACT
Neste estudo nós usamos a prova rotatória pendular decrescente e comparamos as respostas nistágnicas dos canais semicirculares horizontais com as do canal semicircular vertical. Com a cabeça nas diferentes posiçöes obtivemos nistagnos oblíquos vertical rotatório. Nós comparamos os limiares de um lado em relaçäo ao outro. Estes valores foram também comparados com as respostas dos canais horizontais. Nos observamos que o canal semicircular horizontal pareceu mais sensível que os canais semicirculares verticais