P50 variations in Behcet's patients without neurologic findings

In the present study, subclinical lesion involvement was investigated using the P50 component in Behcet's patients without neurological manifestation. We performed this clinical research in Erciyes University, Faculty of Medicine between December 2000 and November 2001. The studies were carried out on 18 Behcet's patients without neurologic findings and 18 volunteers for control. Standard Ag/AgCl electrodes in plastic cups were used for monopolar EEG derivations. They were attached with electrode paste and tape at the Cz [vertex] according to the 10-20 system. The auditory stimuli were delivered in pairs. The P50 waves, which may be taken from approximately 50 msec from the stimuli, were collected by computer system. Amplitudes and latencies of the P50 components were measured in the same system. This study showed that the suppression of P50 responses performed by the test stimuli, was significantly more decreased in Behcet's patients than the control subjects. The decrease of the suppression of the auditory P50 response to repeated stimuli reflects a deficit in the central nervous system's ability, such as attention, cognition, and sensory input in Behcet's patients and can be used as a neurophysiological marker in subclinical lesions in these patients

Effect of grayanotoxin-III on mitotic activity of bone marrow cells of mice

Extract of Rhododendron species and honey obtained from such species which are used in folk medicine in Japan and Turkey contain Grayanotoxins. The effects of one of these toxins, grayanotixin-III [GTX-III], on the mitotic activity of bone marrow cells were investigated. The study was carried out on mice which were exposed to GTX-III at the dose of 0.15 mg/kg-1 daily for three weeks. It was shown that the mitotic index of bone marrow cells of mice was decreased by subchronic GTX-III administration and the decrease was statistically significant when compared with control [p<0.05]. As a result, it should be remembered, subchronic exposure to GTX-III, which was contained in toxic honey or extracts of Rhododendron species, suppressed mitotic activity of bone marrow cells of mice

Grayanotoxin content of honey samples from black sea region of Turkey

In this investigation, run honey from Rize and honey combed from Trabzon in July-1990 were used. The samples were investigated microscopically for the pollens of Rhododendron species and their grayanotoxin [GTX] contents were determined by thin-layer chromatography. As a result, we observed that there were no pollens and grayanotoxin in the honey sample from Rize, whereas pollens and GTX-I were identified in the sample from Trabzon

Effects of toxic honey containing grayanotoxin-I on fatigue of frog gastrocnemius muscle

This study aims at investigating the effects of honey containing grayanotoxin-I [GTX-I] on fatigue produced by electrical stimulation in frog gastrocnemius muscle. We used two groups of gastrocnemius muscles isolated from curarized frogs. The isolated muscle preparations in the first group were perfused with Clark-frog-Ringer's and ordinary honey [from Mediterranean Sea region of Turkey] solutions respectively. The second group of preparations were first perfused with Clark-frog-Ringer's then with GTX-I containing toxic honey [from Black Sea Region of Turkey] solutions. Perfusion was made externally, and bipolar Ag/AgCI wire electrodes were used for stimulation. Muscles were stimulated directly with supramaximal square-wave pulses of 0.5 ms at a rate of 30 stimuli/min, and isometric contractions were recorded. As indicators of muscle fatigue we have used the increases both in contraction and relaxation times and the decrease in contractile force. It has been shown that the toxic honey containing GTX-I delayed the muscle fatigue by preventing the decrease in contractile force