Comparison of focally induced epileptiform activities in C57BL/6 and BALB/c mice by using in vivo EEG recording

Epilepsy characterized by repeated seizures is influenced by genetic factors. Seizure response of inbred mouse strains changes depending on the variety of stimuli including chemical (e.g., pentylenetetrazole, nicotine, cocaine, NMDA, kainate), physical (e.g., auditory) or electrical. In this study, we compared the susceptibilities of C57BL/6 and BALB/c mice strains to penicillin induced epileptiform activity (a focally induced, experimental epilepsy model), by analyzing the spike onset latency, spike amplitude and spike frequency. The power spectrums of baseline EEGs were also investigated. We found no alterations of spike onset latencies between the C57 and BALB mice. However, spike amplitudes and spike frequencies were found to be higher in BALB mice than C57 mice. With regard to EEG power spectrum, absolute power of investigated bands was not different between the two strains. Interestingly, the relative power of all investigated bands differed significantly between two strains. The relative power of delta and theta was lower whereas relative power of alpha, beta and gamma was higher in C57 mice compared to BALB mice. In conclusion, our findings showed that BALB mice are more sensitive to penicillin induced epileptiform activity when compared to C57 strain.     

High-dose intravenous immunoglobulin therapy in juvenile myasthenia gravis

Autoimmune neurologic disease management has been significantly modified by the use of high-dose intravenous immunoglobulin (HDIVIG) during the past 15 years. Venous access, readily available IgG (until recently), and the relative lack of serious identifiable complications have prompted its use in myasthenia gravis. In adults, its effectiveness has been inconsistent, with variable acetylcholine receptor (AChR) antibody responses. Ten children were evaluated for clinical responses to, and complications of, HDIVIG. Weekly anti-AChR antibody titers in three patients were obtained. The HDIVIG dosage was 2 gm/kg body weight, infused at variable rates of 2 gm/kg for 1 day, 0.66 gm/kg daily for 3 days, and 0.5 g/kg daily for 4 days; in one patient the total dose was 0.8 gm/kg to correct to the ideal body weight. All children but one tolerated HDIVIG without complications. Eight patients exhibited definite improvement in functional strength after HDIVIG, but a decreasing response to HDIVIG was evident after multiple monthly treatments, warranting the additional use of corticosteroids in two patients. A decrease in anti-AChR antibody levels was observed in the three patients tested, but this decrease was constant in one patient. No correlation was observed between clinical response and antibody titers. HDIVIG is safe and effective in most patients for short-term management of juvenile myasthenia gravis, in myasthenic crises, and in preparing patients for surgery but appears to be of limited long-term benefit.     

Theta burst and conventional low-frequency rTMS differentially affect GABAergic neurotransmission in the rat cortex

Modified cortical excitability following repetitive transcranial magnetic stimulation (rTMS) may be related to short- or long-term synaptic plasticity of neuronal excitation but could also affect cortical inhibition. Therefore, in the rat we tested how three different rTMS protocols, intermittent and continuous theta-burst (iTBS, cTBS), and low-frequency 1 Hz stimulation, change the expression of GAD65, GAD67 and GAT-1 which are expressed in cortical inhibitory interneurons in an activity-dependent manner. Acutely (2 h), all protocols reduced the expression of GAD67 in frontal, motor, somatosensory and visual cortex but increased that of GAD65 and GAT-1 to different degree, with iTBS having the strongest acute effect. The initial decrease in GAD67 reversed after 1 day, leading to a strong increase in GAD67 expression for up to 7 days primarily in the frontal cortex in case of iTBS, cTBS and in all studied areas following 1 Hz rTMS. While also GAD65 and GAT-1 expression reversed after 1 day in case of iTBS and cTBS, 1 Hz rTMS induced a steady increase in GAD65 and GAT-1 expression during the 7 days investigated. Our data demonstrate that rTMS affects the expression of activity-dependent proteins of the cortical inhibitory interneurons. Besides common effects of low- (1 Hz) and high-frequency (TBS) stimulation on protein expression, differences in quantity and time course of changes point to differences in the contribution of possible neuronal subsystems. Further studies are needed to distinguish cell-type specific effects.     

Local peptidergic innervation of gingiva in smoking and non-smoking periodontitis patients

BACKGROUND: The present study aimed to investigate the local peptidergic innervation of diseased and healthy periodontia in smokers and non-smokers. METHODS: Fifteen smokers and 12 non-smokers, all with localized chronic periodontitis, participated in the study. Periodontally diseased and healthy tooth sites were selected in smokers (groups 1 and 2, respectively) and non-smokers (groups 3 and 4, respectively). Local peptidergic innervation was assessed by the concentrations of two neuropeptides, substance P (SP) and calcitonin gene-related peptide (CGRP), in the gingival biopsies obtained from the groups. Clinical data and biopsies were collected from the same two tooth sites in each group. SP and CGRP levels were measured by enzyme immunosorbent assay in the supernatants of gingival samples. RESULTS: Increased probing depth and attachment loss were found in group 1 compared to group 3 (P<0.05). SP was higher in group 1 compared to groups 2, 3, and 4, and it was higher in group 3 compared to groups 2 and 4 (P<0.05). CGRP was higher in group 1 than in groups 2, 3, and 4, but it was lower in group 3 than in groups 2 and 4 (P<0.05). CONCLUSION: The study results suggested that 1) although smoking may affect the neurogenic inflammation in the presence of periodontitis by increasing local peptidergic innervation, this effect may not be seen in periodontal health, and 2) SP may be regarded as an indicator of periodontitis, whereas CGRP may be important in the acute and/or initial periodontal inflammation.     

Validity and reliability study of Turkish version on low vision with quality of life questionnaire

AIM: To adapt the low vision-related quality of life (LVQOL) instrument into Turkish language and to assess its validity and reliability. METHODS: The study was conducted in 387 patients attending the Centre of Low Vision Rehabilitation, Faculty of Medicine, Ankara University. For statistical analyses, the Spearman's correlation coefficient, Cronbach's alpha coefficient and Confirmatory Factor Analysis (CFA) were used. RESULTS: According to results of CFA, the item in the "Adjustment" subscale because of having the factor loading below 0.40, was excluded from the questionnaire. The reliability of the questionnaire was assessed according to Cronbach’s alpha coefficients. The reliability of the “Distance Vision, Mobility, and Lighting” subscale was α=0.863; of the “Adjustment” subscale wasα=0.694; “Reading and Fine Work” wasα=0.791, and “Activities of Daily Living” wasα=0.770. So these results indicate that the questionnaire is reliable to measure the vision related quality of life of low-vision patients. The correlations between the subscales were also analyzed, and the correlation between "Adjustment" and "Reading and Fine Work" was found to be the lowest (rs=0.336, P<0.001), whereas the strongest correlation was found between the "Reading and Fine Work", and "Activities of Daily Living". Additionally, the "Adjustment" dimension showed the strongest correlation with only "Distance Vision, Mobility, and Lighting" dimension. CONCLUSION: After removing the last item in the second dimension, the Turkish adaptation of all dimensions of the LVQOL has been shown to be reliable, valid and suitable for use in patients with low vision in Turkey.