Biomedical subjects
Publications and source records attributed to W Kawohl.
Plant poisonings have been reported since ancient times. Despite this, little attention is paid to intoxications with herbal poisons by psychiatric literature and the danger from poisonous plants is commonly underestimated. This problem is discussed here, and advice for the prevention of plant poisonings and generally dealing with patients intoxicated by herbal poisons is given.
In routine clinical work, the psychopathology of some patients makes distinct diagnosis more difficult for the psychiatrist. In schizophrenia, especially those patients with dominant autism, eccentric behaviour, and abnormalities of affect with no evidence of positive symptoms pose special diagnostic problems. We report a case with formal thought disorder, autism, altered interactional behaviour, and disturbed emotional expression with no characteristic schizophrenic perception disorders, delusions, or other positive symptoms. With the help of this exemplary case, we discuss the diagnostic dilemma in careful use of diagnostic criteria in diagnosing schizophrenia in such cases.
Psychophysical observations after anesthesia of the thumb raise the question whether the functional border between the thumb and the index is functionally distinct. We present a source localization study using equivalent current dipole modeling of somatosensory evoked potentials (SEPs) following mechanical air-puff stimulation of the first, second and third digits before and during anesthesia of the thumb. Source reconstruction was based on 96-channel SEP recordings. During anesthesia of the thumb the distance between the cortical representation of the thumb and the second and third digits immediately decreased. This indicates a shift of the cortical representation of the second and third digits towards the deafferented area of the anesthetized thumb. Thus, the present results did not confirm the hypothesis of a functional border of the cortical representation between thumb and index finger in this particular task.
OBJECTIVES: Ischaemic stroke attributable to malignant brain tumour is a rarely reported phenomenon and even various imaging techniques including angiography do not necessarily lead to an accurate diagnosis. CASE DESCRIPTION: A 46-year-old, previously healthy man developed apoplectic symptoms with slight right sided hemiparesis and global aphasia. The computed tomography (CT) scan showed lesions of the left temporal lobe and the paraventricular white matter suggestive of left middle cerebral artery (MCA) infarction. Carotid angiography demonstrated compression of the M1 segment of the MCA and occlusion of temporal MCA. The patient initially refused magnetic resonance imaging (MRI) because of claustrophobia. Because of fluctuating symptoms and successive worsening of the condition over weeks an MRI scan was conducted under general anaesthesia. Beneath temporal, opercular, and subcortical infarctions it revealed a left temporal tumour. A tumour biopsy disclosed a gliosarcoma (WHO grade IV). Microscopical examination of the surgical specimen demonstrated invasion of tumour cells into the wall of a greater pre-existing blood vessel. CONCLUSIONS: Malignant brain tumours may cause ischaemic infarction. This is a rare but important differential diagnosis for the origin of strokes. The authors describe the first case with infiltration of intracranial blood vessels by tumour cells of a gliosarcoma.
We investigated the generators of the mismatch negativity by means of spatio-temporal source imaging on the basis of 64-channel electroencephalography data in order to study the time course and localization of proposed frontal sources. Results indicate that there are additional generators located both within the anterior cingulate gyrus and in the right inferior temporal gyrus, clearly separated from the supratemporal generators in space and time course. The cingulate generator is activated later than the temporal ones, which supports the hypothesis of a frontally located mechanism of involuntary switching of attention triggered by the temporal change detection system. Evidence for an additional right inferior temporal generator supports the hypothesis of right hemispheric dominance in early sound discrimination.