Methyl donor supplementation alters serum leptin levels and increases appetite but not body weight in cross-fostered male Syrian hamster offspring (Mesocricetus auratus).

A pregnant hamster's exposure to changes in environmental factors, such as light, temperature and nutrition, may influence behavioural and physiological changes in offspring. In this study, dietary methyl donor supplementation was employed to examine the role of maternal diet on appetite, body weight, serum leptin levels and locomotor activity in male Syrian hamster offspring. Dams were fed a standard control (SC) or methyl donor-supplemented (MDSD) diet through pregnancy and lactation. At birth, offspring were cross-fostered to dams fed an SC or MDSD diet (SC-MDSD and MDSD-SC) or remained with their birth mothers (SC-SC and MDSD-MDSD). At weaning, offspring were fed a SC or MDSD diet until 60 days of age. Food intake, serum leptin levels and locomotor activity were measured from 30-60 days of age. Offspring fed a MDSD diet post-weaning (MDSD-MDSD and SC-MDSD) consumed more than double the amount of food daily compared with offspring fed a SC diet post-weaning (SC-SC, MDSD-SC). Interestingly, there were no observed differences in body weight among all four groups. Serum leptin levels at 60 days of age were depressed in offspring fed a MDSD diet post-weaning (MDSD-MDSD and SC-MDSD). There were no observed differences in wheel running activity between the SC-SC and MDSC-SC groups. Wheel running activity was at least twice the amount in offspring fed a MDSD diet post-weaning (SC-MDSD and MDSD-MDSD). Taken together, these results indicate that the timing of methyl donor supplementation appears to be an important factor during the development of offspring.

Long-term Average Speech Spectra of Postlingual Cochlear Implant Users.

Long term average speech spectra (LTASS) is a commonly used voice analysis method for different purposes. This method offers an acoustic representation of the language in daily conservations. Results of that method can be altered by the deteriorations in the auditory feedback loop. Hearing losses occurred in the post lingual stage of life have some serious negative effects on the auditory feedback loop. Cochlear implantation may help these patients with regards to auditory feedback loop. Therefore, we aimed to evaluate the LTASS of cochlear implant users whose have a post lingual hearing loss. We assessed the LTASS of 24 cochlear implant users and compared our findings with normal hearing subjects. Our findings revealed that cochlear implant users have similar LTASS findings with normal hearing subjects. We conclude that cochlear implantation helps to the recovery of auditory feedback loop in patients with post lingual hearing losses.

The effects of the intraamygdalar melatonin injections on the anxiety like behavior and the spatial memory performance in male Wistar rats.

In the present study, the effects of intraamygdalar administrations of melatonin (1 and 100µg/kg), saline and diazepam on the anxiety-like behavior and spatial memory performance in pinealectomized and sham-pinealectomized Wistar rats were investigated. The animals were tested by open field and elevated plus maze tests for anxiety-like behavior, and Morris water maze test for spatial memory. In open field, (a) diazepam was more effective in reducing the anxiety, (b) control subjects were more mobile than pinealectomized subjects and (c) 100µg/kg melatonin administrations reduced the velocity of the animals. In elevated plus maze, (a) 100µg/kg melatonin administrations increased the distance totally travelled and (b) enhanced the time spent in open arms, however, after the pinealectomy, 1µg/kg melatonin administrations decreased it and (c) control animals were less mobile than pinealectomized ones. In Morris water maze, (a) diazepam group travelled more distance than the others in control condition whereas, in pinealectomy condition high dose of melatonin and saline groups travelled more distance than the others, (b) in pinealectomy condition subjects who received 100µg/kg melatonin also travelled more distance than those who received 1µg/kg melatonin and diazepam, (c) the subjects who received 1µg/kg spent less time than those who received other treatments, and (d) in control condition subjects who received 100µg/kg melatonin were slower than those who received the other treatments. In conclusion, melatonin administration to amygdala decreased the anxiety; however, spatial memory performance of the rats was impaired by the pinealectomy and melatonin administrations.

Effects of pinealectomy and melatonin supplementation on endometrial explants in a rat model.

OBJECTIVE: To determine the effects of pinealectomy on endometrial explants in rats and evaluate the activity of superoxide dismutase (SOD) and catalase (CAT) and the levels of malondialdehyde (MDA) in the rat endometriosis model. STUDY DESIGN: Rats with experimentally induced endometriosis were randomly divided into three groups after second-look laparotomies. Group 1 (pinealectomy, n = 8) and Group 2 (pinealectomy+melatonin, n = 8) underwent pinealectomies after the second-look laparotomies. Group 3 was presented as control group (vehicle solution+without pinealectomy (n = 6)). Melatonin was administered intraperitoneally for 4 weeks in Group 2, whereas an equal volume of vehicle solution was given to Groups 1 and 3. Evaluation of the volume of the endometrial explants, histopathological examination and preservation of explant epitheliums according to the scoring system were undertaken. RESULTS: There was a statistically significant increase in spherical explant volumes of Group 1 compared to Groups 2 and 3. In Group 1, the level of MDA was significantly higher and SOD and CAT activity was significantly lower compared to Groups 2 and 3. A statistically significant increase in the epithelial lining scores of explants was noted in Group 1 compared to Groups 2 and 3. CONCLUSION: The effects of pinealectomy on the progression of endometriosis explants were reversed by melatonin.

Otoacoustic emissions and effects of contralateral white noise stimulation on transient evoked otoacoustic emissions in diabetic children.

OBJECTIVE: In this study, our aim was to determine presence of dysfunction in the efferent auditory system of children with type-I diabetes mellitus (DM) presenting no evidence of symptomatic neuropathy. METHODS: Thirty children with type-I DM (DM group) and 31 age matched healthy children (control group) with normal hearing and middle ear function were entered to the study. Distortion product otoacoustic emissions (DPOAE), transiently evoked otoacoustic emissions (TEOAE), and spontaneous otoacoustic emissions (SOAE) measurements were performed. Then, the TEOAE recording was repeated while a continuous broadband white noise (bandwidth: 50-8000 Hz) presented at 40 dB SL was delivered to the contralateral ear for efferent auditory system suppression. RESULTS: We found that contralateral stimulation (CS) with white noise resulted in significantly more pronounced suppression of the TEOAE response amplitude in healthy controls compared to DM group at 2000 and 4000 Hz frequencies. Further, a relatively higher percentage of the controls had suppression in at least three frequencies compared to DM group. SOAE prevalence was found to be higher in the DM group. CONCLUSIONS: Our findings suggest presence of a dysfunction in medial olivocochlear efferent system in diabetic children. This may be regarded as an early central manifestation of diabetic neuropathy.

Effects of European mistletoe (Viscum album L. subsp. album) extracts on activity rhythms of the Syrian hamsters (Mesocricetus auratus).

Antitumor drugs may have some significant nervous system side-effects such as disrupted sleep, eating and drinking patterns. European Mistletoe has been investigated for many decades for its potential use against cancer. To test the hypothesis that the non-antineoplastic effects of mistletoe might be mediated by the actions on the circadian timing system, we have applied mistletoe extracts and vehicle and have measured locomotor activity, feeding and drinking rhythms under constant darkness. Four groups (vehicle, 20 mg kg(-1) ip injection, 40 mg kg(-1) ip injection and 6 g kg(-1) oral administration) were performed for both heat-treated and freeze-dried extracts. None of the administrations changed the locomotor activity, feeding and drinking rhythms in the groups except for 40 mg kg(-1) freeze-dried injected group. The locomotor activity levels decreased in 40 mg kg(-1) freeze-dried extract injected group. These results suggest that, side-effects of mistletoe on circadian timing system of the Syrian hamster depend on the dose and the preparation method of the extract.

Distortion product otoacoustic emission findings in Behçet's disease and rheumatoid arthritis.

BACKGROUND AND OBJECTIVE: This study aimed to assess cochlear functions in Behçet's disease and rheumatoid arthritis (RA) using otoacoustic emission testing (OAE), which objectively assesses outer hair cells in the cochlea. METHODS: Patients with Behçet's disease (n = 16) and RA (n = 11) as well as 20 controls were tested using pure tone audiometry and transiently evoked (TEOAEs) and distortion product OAEs (DPOAEs). RESULTS: Pure tone results in the Behçet's group were not significantly different from controls (p > 0.05). Pure tone results in the RA group were significantly different than in controls at 250, 500 and 6,000 Hz (p < 0.05). TEOAEs could be obtained in all participants. DPOAE amplitudes in the RA group and controls were similar (p > 0.05). DPOAE amplitudes were significantly higher in the Behçet's group than in controls at 1 and 2 kHz (p < 0.05). CONCLUSION: A subtle deterioration in hearing can be seen at low and high frequencies in RA, which is not related to outer hair cell dysfunction as detected by DPOAE testing. In the patients with Behçet's disease who have hearing thresholds within the normal limits, outer hair cell functions seem spared with an increased activity in the apical regions of the cochlea.