Biomedical subjects
Publications and source records attributed to H Sass.
Elementary geometric imagery seen in the visual aura of migraine can be experienced as incorporated into the content of a dream which precedes the awakening with a migraine headache. Furthermore, recurrent dreams featuring complex visual imagery, often terrifying nightmares, can occur as migraine aura symptoms. The said phenomena are illustrated by two original case reports and discussed against the background of a review of the literature.
The German philosopher Immanuel Kant (1724-1804) suffered, since his forties, from a migraine with aura which showed a significant exacerbation in his seventies, coinciding with the onset of symptoms of a senile dementia of Alzheimer's type. Recorded symptoms of Kant's migraine include recurrent scintillating scotomas, one episode of diplopia, two episodes of complete amaurosis and frequent headaches described as oppressions of the head. The said symptoms of Kant's migraine can be traced not only in his letters and in accounts of his contemporary biographers, but also in the philosopher's published work.
The development of symptoms of posttraumatic stress disorder (PTSD) in patients with neurogenic amnesia for the traumatic event is recorded in 2 own patients and in 19 cases from the clinical literature. With a single exception, all patients were accident victims with closed head injuries. Only about three quarters of the patients completely fulfilled DSM-III-R criteria of PTSD. Nineteen patients displayed involuntary conscious memories of aspects of the traumatic event (presenting as recurrent intrusive thoughts, images or dreams) co-existent with a complete or partial lack of voluntary conscious memories of the trauma, suggesting that different memory systems and distinct brain mechanisms subserve these phenomena. The said clinical observations are discussed against the background of current neuropsychological models of multiple memory systems. The recorded cases demonstrate that declarative episodic memory is not necessary for symptoms of PTSD to emerge, whereas preserved functions of non-declarative memory systems represent a sufficient condition for the development of PTSD symptoms.
In borderline and antisocial personality disorder there is a close interaction between affect dysregulation and impulse control disorder. Different approaches are presented that focus on affective responses to experimental stimuli in these personality disorders. Results suggest that in borderline personality disorder intense emotional responses occur in the context of specific stressors, in particular fear of being abandoned. Evidence for a general emotional hyperreactivity was not found; on the contrary, female borderline subjects rather showed reduced emotional arousal. Regarding the psychopathic subtype of antisocial personality disorder, results provided strong support for the theory of emotional detachment, which may predispose to violence through a lack of feeling of fear or also of compassion which could counteract violent impulses. Consequences for psychotherapy in BPD are considered.
OBJECTIVES: Ecstasy (3,4-methylenedioxymethamphetamine (MDMA) and related congerers: MDA, MDEA) is the name given to a group of popular recreational drugs. Animal data raise concern about neurotoxic effects of high doses of ecstasy on central serotonergic systems. The threshold dose for neurotoxicity in humans is not clear and serotonin is involved in several functions including cognition. The purpose of this study was to investigate cognitive performance in a group of typical recreational ecstasy users. METHODS: A comprehensive cognitive test battery was administered to 28 abstinent ecstasy users with concomitant use of cannabis only and to two equally sized matched groups of cannabis users and non-users. The sample consisted of ecstasy users with a typical recreational use pattern and did not include very heavy users. RESULTS: Ecstasy users were unimpaired in simple tests of attention (alertness). However, they performed worse than one or both control groups in the more complex tests of attention, in memory and learning tasks, and in tasks reflecting aspects of general intelligence. Heavier ecstasy and heavier cannabis use were associated with poorer performance in the group of ecstasy users. By contrast, the cannabis users did not differ significantly in their performance from the non-users. CONCLUSIONS: The present data raise concern that use of ecstasy possibly in conjunction with cannabis may lead to cognitive decline in otherwise healthy young people. Although the nature of the emerging cognitive disturbance is not yet clear, an impairment of working memory might be the common denominator underlying or contributing to declines of performance in various tasks. The cognitive disturbance is likely to be related to the well recognised neurotoxic potential of ecstasy. The data suggest that even typical recreational doses of ecstasy are sufficient to cause neurotoxicity in humans.
The aim of this study was to assess psychophysiological affect correlates, in addition to the usual self-report in borderline personality disorder (BPD) compared with avoidant personality disorder (APD) and normal controls (NCs), when responding to standardized experimental stimuli. In 24 BPD female patients, 23 APD female patients, and 27 female NCs, skin conductance response (SCR), heart rate (HR) change, and startle response were recorded while the subjects viewed slides with emotional content. Neither the self-report nor the psychophysiological data supported the hypothesis that affective responses of BPD individuals are generally stronger than those with APD. BPD patients showed no potentiation of the affective modulation of the startle reflex and their electrodermal reactivity was lower than in either the APD subjects or the NCs. The hypothesis of a general affective hyperresponsivity could not be confirmed. Low somatic arousal in BPD can interfere with the anticipation of signal stimuli and may explain the exaggerated openness borderline personalities show to stimuli, particularly in interpersonal situations.
Single photon emission computed tomography with technetium-99m-d,l-hexamethylpropyleneamine oxime (99mTc-HMPAO) was used to assess regional cerebral blood flow (rCBF) during both florid and remitted stages of schizophrenia. Forty schizophrenic patients in an active phase of illness (diagnosis by DSM-III-R) were examined in two clinical states (ill vs. improved). At study entry, 24 patients were drug-naive, five were currently drug-free, and 11 were being treated with antipsychotic medication. Twenty medical patients who suffered from non-specific headaches but were free of neurological and psychiatric symptoms served as control subjects. At initial examination during the active phase of illness, cerebral perfusion patterns in the schizophrenic patients were characterized by both hypofrontality and hypotemporality. After remission, hypofrontality was no longer apparent in two of four frontal regions, and hypotemporality disappeared completely. As assessed with the Positive and Negative Syndrome Scale (PANSS), formal thought disorders, hallucinations, and ideas of grandiosity correlated with rCBF in the active phase of illness, but not after remission. In the remitted but not in the florid state, blunted affect, difficulties in abstract thinking, lack of spontaneity, and stereotyped thoughts correlated with rCBF. Correlations of five symptoms with rCBF changed significantly from first to second examination. The present study suggests that correlations between single psychotic symptoms and rCBF differ significantly in florid vs. remitted phases of schizophrenia.
The construct Quality of Life (QoL) is investigated by metaanalysis of eight (inter)nationally validated questionnaires in a multicenter study. Data have been collected in a mentally healthy (n = 479), a depressed (n = 171) and a schizophrenic (n = 139) sample. Conventional psychometric criteria and a facet analytical methodology have been applied. The resulting questionnaire "Modular System for Quality of Life" (MSQoL) consists of a core module with 47 items (one "G-factor" and six subdimensions), which is sufficiently valid for all three samples. Additionally, there are four specific modules (demography, family, partnership, profession). No specific modules can be identified for the psychopathological subgroups. The validated radex structure for subjective QoL offers the opportunity for a cumulative research design and for adaptations to the actual setting.
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The aim of this study was to contribute to the characterization of the entactogen (ecstasy) substance group. The psychopathological, neuroendocrine and autonomic effects of common recreational doses of the entactogen 3,4-methylenedioxyethylamphetamine (MDE), the hallucinogen psilocybin, the stimulant d-methamphetamine and placebo were investigated in a double-blind study with healthy volunteers (n = 32). Psychological effects of the drugs were assessed by means of standardized rating scales, self assessment inventories and free descriptions. The most characteristic effects of MDE were pleasant emotional experiences of relaxation, peacefulness, content and closeness to others. However, significant stimulant and hallucinogen-like effects were also present, although the latter were weaker than the effects of psilocybin. MDE elicited the strongest endocrine and autonomic effects among the three drugs, including robust rises of serum cortisol and prolactin, elevations of blood pressure and heart rate, and a moderate, but significant rise of body temperature. The apparent contrast between psychological and autonomic effects (subjective relaxation versus physical activation) was a unique feature of the MDE state. Our findings are in line with both users' reports and results from previous experimental studies, and support the view that entactogens constitute a distinct psychoactive substance class taking an intermediate position between hallucinogens and stimulants.
The aim of this study was to determine the acute effects of the "Ecstasy" analogue MDE (3,4-methylene dioxyethamphetamine) on cerebral glucose metabolism (rMRGlu) of healthy volunteers and to correlate neurometabolism with acute psychopathology. In a randomized double-blind trial, 15 healthy volunteers without a history of drug abuse were examined with fluorine-18-deoxyglucose (18FDG) positron emission tomography (PET) 110-120 min after oral administration of 2 mg/kg MDE (n = 7) or placebo (n = 8). Two minutes prior to radiotracer injection, constant cognitive stimulation was started and maintained for 32 min using a word repetition paradigm to ensure constant and comparable mental conditions during cerebral glucose uptake. Individual brain anatomy was represented using Tl-weighted 3D flash magnetic resonance imaging (MRI), followed by manual regionalization into 108 regions of interest and PET/MRI overlay. After absolute quantification of rMRGlu and normalization to global metabolism, normalized rMRGlu under MDE was compared to placebo using the Mann-Whitney U-test. Acute psychopathology was assessed using the Positive and Negative Syndrome Scale (PANSS) and rMRGlu was correlated to PANSS scores according to Spearman. MDE subjects showed significantly decreased rMRGlu in the bilateral frontal cortex: left frontal posterior (-7.1%, P < 0.05) and right prefrontal superior (-4.6%, P < 0.05). On the other hand, rMRGlu was significantly increased in the bilateral cerebellum (right: +10.1%, P < 0.05; left: +7.6%, P < 0.05) and in the right putamen (+6.2%, P < 0.05). There were positive correlations between rMRGlu in the middle right cingulate and grandiosity (r = 0.87, P < 0.05), both the right amygdala (r = 0.90, P < 0.01) and the left posterior cingulate (r = 0.90, P < 0.01) to difficulties in abstract thinking, and the right frontal inferior (r = 0.85, P < 0.05), right anterior cingulate (r = 0.93, P < 0.01), and left anterior cingulate (r = 0.85, P < 0.05) to attentional deficits. A negative correlation was found between the left frontal operculum (Broca's area) and attentional deficits (r = -0.85, P < 0.05). The present study revealed acute neurometabolic changes under the "Ecstasy" analogue MDE, indicating a frontostriatocerebellar imbalance paralleling other psychotropic substances or various psychiatric disorders.
The neurometabolic effects of the hallucinogen psilocybin (PSI; 0.2 mg/kg), the entactogen 3,4-methylenedioxyethylamphetamine (MDE; 2 mg/kg) and the stimulant d-methamphetamine (METH; 0.2-0.4 mg/kg) and the drugs' interactions with a prefrontal activation task were investigated in a double-blind, placebo-controlled human [F-18]fluorodeoxyglucoseFDG-positron emission tomographicPET study (each group: n = 8). Subjects underwent two scans (control: word repetition; activation word association) within 2-4 weeks. Psilocybin increased rMRGlu in distinct right hemispheric frontotemporal cortical regions, particularly in the anterior cingulate and decreased rMRGlu in the thalamus. Both MDE and METH induced cortical hypometabolism and cerebellar hypermetabolism. In the MDE group, cortical hypometabolism was more pronounced in frontal regions, with the exception of the right anterior cingulate, which tended to be hyperactive. Cognitive activation-related increases in left frontocortical regions were attenuated under all three psychoactive substances, but less so under MDE. Taking into account performance data and subjective reports on task difficulty, these effects may result from different mechanisms across the three groups. Our PSI data are in line with studies on acute schizophrenic patients suggesting frontal overactivity at rest, but diminished capacity to activate prefrontal regions upon cognitive demand. The MDE data support the hypothesis that entactogens constitute a distinct psychoactive substance class, which takes an intermediate position between stimulants and hallucinogens.
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INTRODUCTION: The hypothesis of prefrontal-temporolimbic disconnectivity, considered to be relevant to the pathogenesis of schizophrenia, has been tested in 29 drug-naive schizophrenic patients, comparing the active with the remitted state. METHOD: A pre-post-treatment design was applied to 29 drug-naive schizophrenic inpatients, 18 male, mean age 32 years, 11 female, mean age 32 years, mean duration of illness 29 months. Psychopathological symptoms were assessed using PANSS, regional cerebral blood (rCBF) was measured by HMPAO-SPECT. RCBF values were calculated for 21 regions of interest after normalization to cerebellum, and plotted by Euklidean diagrams using the ordinal, nonmetric, multidimensional scaling method. These diagrams represent similarity correlations visualized as spatial distances. High correlation levels as indicated by small Euklidean distances have been interpreted as functional connectivity. RESULTS: In active schizophrenia, functional disconnectivity was observed between prefrontal and temporal cortex. After remission, connectivity was improved between temporolimbic and frontal cortex. CONCLUSION: Comparing active with remitted schizophrenia, a frontotemporal disconnectivity appears. Temporolimbic as well as frontolimbic connections restitute parallel to psychopathological improvement.
A Gram-negative, anaerobic sulfate-reducing bacterium was isolated from hindgut contents of the lower termite Mastotermes darwiniensis Froggatt (strain KMS2). Strain KMS2 is motile by a single polar flagellum. The isolate possesses desulfoviridin and catalase activity. The G+C content of its DNA is in the range of 54.5-55.5 mol% (strain KMS2). It respires hydrogen and different low molecular weight organic compounds in the presence of sulfate, thiosulfate, and sulfite, and also oxygen. The isolated strain ferments pyruvate. Fastest growth with a doubling time of 12.5 h was obtained at 37 degrees C and not at 28 degrees C, the temperature at which the termites were grown. The isolate showed a 16S rDNA sequence homology of 95.9% to Desulfovibrio desulfuricans ATCC 27774 and a DNA-DNA homology of 44.6% to D. desulfuricans Essex 6 (type strain). Based on its biochemical properties and 16S rDNA sequence, the isolate was assigned to a new species named Desulfovibrio intestinalis.
OBJECTIVE: The aim of the study was to investigate affective responses to emotional stimuli in subjects with borderline personality disorder. METHOD: Twenty-four female patients with borderline personality disorder and 27 normal female comparison subjects were examined. The test stimuli were a set of standardized photographic slides with pleasant, neutral, or unpleasant emotional valence. In addition to self-reports, emotional reactions to the slides were measured by heart rate, skin conductance, and startle response. Psychometric tests for various aspects of impulsiveness were also completed. RESULTS: Neither self-report nor physiological data gave any evidence that the borderline patients showed more intense affective responses than did the normal subjects. The borderline subjects did not produce higher levels of startle amplitude, and while viewing unpleasant slides, they showed a startle potentiation effect that was largely similar to that of the comparison group. In fact, the borderline patients showed low electrodermal responses to all three stimulus categories, which points to physiological underarousal. CONCLUSIONS: The results do not agree with the hypothesis that there is a fundamental, biologically based affective hyperresponsiveness in borderline personality disorder, as is suggested by current theories of affect dysregulation in the disorder. Autonomic underarousal may seriously interfere with a flexible adaptation to environmental stimuli.
Patients with health problems attributed to environmental factors such as chemical pollutants and electromagnetic fields often do not present evidence of an environmental aetiology of their symptoms. It has been postulated, that their problems are due to disorders diagnosed by other medical disciplines, especially allergology and psychiatry. Our study was designed to subject these patients to a comprehensive diagnostic program involving several medical disciplines in order to achieve diagnoses appropriate to explain the patients' symptoms. Fifty patients consecutively referred to the department of environmental medicine in the university hospital of Aachen, Germany, were submitted to the following examinations: (i) environmental medicine (history, clinical examination, biological and/or ambient monitoring for environmental agents); (ii) allergological examination (history, clinical examination, skin tests); (iii) psychiatric examination (psychopathological examination, psychometric and neuropsychological testing). In addition, the patients were examined in other hospital departments according to the symptoms presented. The findings were discussed in case conferences attended by the physicians involved in order to achieve individual diagnoses. The numbers of patients to whom diagnoses were given by different medical disciplines are as follows: psychiatry (32 patients), dermatology (4), allergology (2), neurology (2), rheumatology (2), gynaecology (1), haematology (1). The most frequent mental disorders diagnosed by the psychiatrists were somatoform disorders (19), followed by schizophreniform and delusion disorders (7). In spite of extensive diagnostic efforts, patients with health problems attributed to the environment usually do not present sufficient evidence of an environmental aetiology of their symptoms. On the other hand the symptoms often meet the diagnostic criteria of other diseases, especially of mental disorders.
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