Adriana de Andrade Batista Murashima

The topical use of insulin accelerates the healing of traumatic Tympanic membrane perforations

In recent years, there has been a tendency to search for regulatory substances that can optimize the healing process of perforated tympanic membranes (TMs). The purpose of this study was to determine the effects of using topical insulin on the healing process of traumatic TMs perforations.

Spontaneous healing of the tympanic membrane after traumatic perforation in rats

UNLABELLED The most common etiologies of tympanic membrane perforation are infections and trauma. OBJECTIVE The objective of the present study was to assess the healing of traumatic tympanic membrane perforation in rats. METHODS The tympanic membrane from male Wistar rats was perforated in the anterior and posterior portions to the handle of the malleus. Five tympanic membranes were evaluated 3 days after tympanic perforation; 5 after 5 days; 5 after 7 days; 3 after 10 days; and 4 after 14 days. The tympanic membranes were submitted to histopathological evaluation after hematoxylin-eosin staining. RESULTS Tympanic membrane closure occurred at about 7-10 days after injury and the healing process was complete by day 14. The proliferative activity of the outer epithelial layer was present close to the handle of the malleus and to the tympanic annulus. CONCLUSION The spontaneous healing process of the tympanic membrane starts from the outer epithelial layer, with later healing of the lamina propria and the mucosal layer.

Efeito da oxigenação hiperbárica em lesão ototóxica produzida pela amicacina em cobaias

UNLABELLED Hyperbaric oxygen therapy (HBOT) has enhanced the prevention and treatment of auditory ailments such as ototoxicity. OBJECTIVE To study the effects of HBOT upon ototoxic injuries produced by amikacin. METHOD This experimental study included 12 albino guinea pigs, whose auditory function was assessed through distortion product otoacoustic emissions (DPOAEs) and brainstem auditory evoked potentials (BAEPs) before and after the administration of amikacin (600 mg/kg/day) and HBOT sessions (2 ATA, 60 minutes). Morphological features were analyzed through scanning electron microscopy. Subjects were divided into four groups, as follows: group 1 - saline solution + HBOT; group 2 - amikacin for 8 days; group 3 - amikacin + seven days of rest; and group 4 - amikacin + HBOT. RESULTS Group 1 subjects had preserved function and morphology throughout the experiment; Group 2 subjects had statistically significant levels of hair cell injury and functional impairment; Subjects on groups 3 and 4 had statistically significant functional and morphological impairment after the administration of amikacin, which were still present after the proposed procedures had been carried out. CONCLUSION Hyperbaric oxygen therapy did not change the cochlear hair cell morphology or the electro-physiological thresholds of the guinea pigs given amikacin.

Assessing the maxillary sinus mucosa of rabbits in the presence of biodegradable implants

UNLABELLED In an attempt to improve the quality of life of patients with vitreous humor disease, ophthalmologists began offering steroid-eluting biodegradable implants to their patients. These implants can be used as an alternative treatment for CRS and this is why this experimental study was carried out on rabbit maxillary sinuses. OBJECTIVE This study aims to assess the histology of the mucosa of the maxillary sinuses of rabbits after the placement of a prednisolone-eluting biodegradable implant. METHOD Eighteen rabbits were randomly divided into two groups: group 1 - subjects had drug-eluting implants placed on their left maxillary sinuses; group 2 - subjects had non-drug-eluting implants placed on their left maxillary sinuses. The right maxillary sinuses served as the controls. After seven, 14, and 28 days three rabbits in each group were randomly picked to have their tissue inflammatory response assessed. RESULTS Levels of mucosal inflammation were not significantly different between the groups with and without drug-eluting implants and the control group, or when the groups with drug-eluting implants and non-drug-eluting implants were compared. CONCLUSION Signs of toxicity or mucosal inflammation were not observed in the maxillary sinuses of rabbits given prednisolone-eluting implants or non-drug-eluting implants.

Macroscopic description of the external and middle ear of paca (Cuniculus paca Linnaeus, 1766)

Paca (Cuniculus paca), one of the largest rodents of the Brazilian fauna, has inherent characteristics of its species which can conribute as a new option for animal experimantation. As there is a growing demand for suitable experimental models in audiologic and otologic surgical research, the gross anatomy and ultrastructural ear of this rodent have been analyzed and described in detail. Fifteen adult pacas from the Wild Animals Sector herd of Faculdade de Ciencias Agrarias e Veterinarias, Unesp-Jaboticabal, were used in this study. After anesthesia and euthanasia, we evaluated the entire composition of the external ear, registering and ddescribing the details; the temporal region was often dissected for a better view and detailing of the tympanic bulla which was removed and opened to expose the ear structures analyzed mascroscopically and ultrastructurally. The ear pinna has a triangular and concave shape with irregular ridges and sharp apex. The external auditory canal is winding in its path to the tympanic mebrane. The tympanic bulla is is on the back-bottom of the skull. The middle ear is formed by a cavity region filled with bone and membranous structures bounded by the tympanic membrane and the oval and round windows. The tympanic membrane is flat and seals the ear canal. The anatomy of the paca ear is similar to the guinea pig and from the viewpoint of experimental model has major advantages compared with the mouse ear.

Avaliação funcional do sistema vestibular de cobaias intoxicadas agudamente por organofosforado por meio da prova calórica

PURPOSE:this study aimed to assess the functioning of the vestibular system of guinea pigs exposed to the organophosphate chlorpyrifos, acutely, through caloric stimulation electronystagmography.METHODS:the research conducted an experimental electronystagmography of guinea pigs exposed to organophosphate for 10 consecutive days, at doses 0.5 mg / kg / day and 1.0 mg / kg / day intraperitoneally and compared with a control group that received distilled water administration. We performed caloric ice (10 o C) and compared the variables frequency of appearance of nystagmus in 10 seconds (u / s) and angular velocity of the slow component (o / s).Results:the results showed no statistically significant difference in the comparison of variables between groups.CONCLUSION:we conclude that the tested doses of the pesticide organophosphate chlorpyrifos caused no detectable functional damage in the caloric test.