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Objective-To investigate the eVect of radiosurgery for symptomatic epilepsy associated with cerebral arteriovenous malformations (AVMs). Methods-Thirty five patients with unruptured epileptogenic AVMs were studied with a mean follow up of 43.0 months. The duration of epilepsy before radiosurgery ranged from 2 months to 21 years (mean 2.8 years). Fifteen patients showed partial seizures; eight of these had associated secondary generalisation. The remaining 20 patients showed only generalised seizures without preceding focal seizures. Results-At the final follow up examination, 28 patients remained seizure free, whereas seizures continued in seven. Variables significantly associated with continuity of seizures after radiosurgery were the number of seizures before therapy (p<0.01) and duration of epilepsy (p<0.05). According to Engel's classification, the 10 patients with intractable seizures before treatment included five with grade I, four with grade III, and one with grade IV. The frequency of seizures began to decrease several months after radiosurgery; much shorter than the time required for morphological change in the AVMs.Conclusions-Radiosurgery seems to be beneficial for seizure control in patients with unruptured epileptogenic AVM. (J Neurol Neurosurg Psychiatry 1998;65:648-655) Keywords: arteriovenous malformation; symptomatic epilepsy; gamma knife; radiosurgery Various therapeutic alternatives are currently available for eliminating the risk of bleeding from cerebral arteriovenous malformations (AVMs), and the reported treatment results have been favourable in terms of overall morbidity and mortality. However, the prognosis of epilepsy associated with cerebral AVMs has received little attention. Controversy exists on the surgical treatment of AVMs associated with epilepsy, and seizure outcome after AVM radiosurgery has not been documented in detail.In this study, we analysed the characteristics and frequency of seizures in 35 patients with epileptogenic unruptured AVMs after gamma knife radiosurgery. A retrospective survey of 22 additional patients with unruptured nonepileptogenic AVMs was also done to assess the development of seizures after the procedure. Here we report the early eVect of focused irradiation on seizures associated with AVMs and discuss the various factors that influence the prognosis. Patients and methods PATIENT POPULATIONBetween June 1990 and December 1995, 315 patients with angiographically demonstrable cerebral arteriovenous malformations (AVMs) underwent radiosurgical treatment at our institution. The initial manifestation at diagnosis was haemorrhage in 228 (72.4%), seizure in 42 (13.3%), headache in 15 (4.8%), progressive or stable neurological deficits in 10 (3.2%), and other clinical symptoms in three (1.0%). In the remaining 17 patients (5.4%), AVM was an incidental finding (table 1).From 42 patients who had epilepsy as a diagnostic symptom, we excluded five who underwent surgical resection or had a bleeding episode before radiosurgery, one whose AVM bled during t...

We have generated mutant mice for epidermal-type fatty acid binding protein by the gene targeting technique and examined the phenotype in detail. Despite a lack in the expression of epidermal-type fatty acid binding protein mRNA and its protein in the skin and other tissues of the mutant mice, the animals appeared normal in gross and histologic examination. Northern blot analysis of other fatty acid binding proteins revealed a distinct elevated gene expression of heart-type fatty acid binding protein in the skin of the homozygous mice. In analyses of the skin, no differences were observed in contents of major fatty acids, electron microscopic appearance as well as inflammatory responses in ear skin between the mutant and wild-type mice. Basal transepidermal water loss of homozygous mice was lower than that of the wild mice. When acetone was applied to the skin for disruption of the water permeability barrier, recovery in transepidermal water loss was delayed, although maximum transepidermal water loss upon acetone treatment was similar between homozygous and wild-type mice in terms of size and time course. The molecular mechanism by which epidermal-type fatty acid binding protein contributes to the water barrier function of the skin remains to be elucidated.

Radiosurgical treatment of intractable epilepsy has emerged as a noninvasive alternative to resection. Although gamma knife surgery (GKS) reportedly is effective when the radiation dose is sufficient to cause a destructive reaction in the targeted medial temporal lobe, the optimal target area and dose distribution are largely unknown. Some investigators have suggested that focused irradiation from a nondestructive dose is also effective. In this article the authors report two cases of medial temporal lobe epilepsy in which the patients underwent GKS performed using a 50% marginal dose of 18 Gy covering the amygdala. hippocampal head and body, and parahippocampal gyrus. In both cases this procedure failed to control seizures. Both patients became seizure free after undergoing anterior temporal lobectomy 30 and 16 months, respectively, after radiosurgery.

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The role of ventral respiratory group (VRG) expiratory (E) neurons in the control of abdominal and internal intercostal (expiratory) muscle activity during vomiting was examined in decerebrate cats by recording from these neurons during fictive vomiting in paralyzed animals and comparing abdominal muscle activity during vomiting before and after sectioning the axons of these descending neurons. Fictive vomiting was defined by a series of bursts of coactivation of abdominal and phrenic nerves elicited by either subdiaphragmatic vagus nerve stimulation or emetic drugs. Such coordinated activity would be expected to produce vomiting if the animals were not paralyzed. Data were recorded from 27 VRG E neurons that were antidromically activated from the lower thoracic (T13) or lumbar spinal cord. During fictive vomiting, almost two-thirds of these neurons (17/27) were mainly active in between periods of abdominal and phrenic nerve coactivation, when the internal intercostal motoneurons are known to be active. This group of neurons was termed INT neurons. INT neurons were subdivided according to whether they were active between every burst of phrenic and abdominal nerve coactivation (INTa neurons, n = 10) or only between some bursts (INTb neurons, n = 7). Another one-third of the VRG E neurons had normal or increased levels of activity when the abdominal nerves were active during fictive vomiting (ABD neurons). The one remaining neuron was mainly silent throughout fictive vomiting. ABD neurons were indistinguishable from INT neurons on the basis of their location in the VRG, type of firing pattern (ramp versus step ramp), conduction velocity, or extent of projection in the lumbar cord. However, INTa neurons had a significantly higher discharge rate during respiration than either ABD or INTb neurons. Abdominal muscle EMG and nerve activity were recorded from six unparalyzed cats before and after cutting the axons of VRG E neurons as they cross the midline between C1 and the obex. The lesions abolished or almost eliminated expiratory modulation of abdominal muscle activity. In contrast, the abdominal muscles were always active during vomiting; however, the amplitude of postlesion abdominal activity varied from approximately 70-100% of prelesion values in three cats to 60-70% of normal in a fourth animal to only approximately 20% of prelesion values in two other cats.(ABSTRACT TRUNCATED AT 400 WORDS)

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In order to elucidate the mechanism of self‐protection of weathering steel, the action of atmospheric rust was studied through a discussion of physical, chemical, and electrochemical nature of rust, with special attention to the effect of copper addition. The aggregating state of rust layer is influenced by two factors: the time of exposure and beneficial elements added to steel. Copper addition inhibits the growth of primary colloidal particle. This action of copper has an effect on the properties of rust and serves to increase the protective ability of rust layer.