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D F Braus

Publications and source records attributed to D F Braus.

50 records · Page 3Linked to original sources
PubMed1996

Decreased phospholipase A2 activity in the brain and in platelets of patients with Alzheimer's disease.

Phospholipase A2 (PLA2) is a key enzyme in the metabolism of membrane phospholipids. PLA2 influences the processing and secretion of the amyloid precursor protein, which give rise to the beta-amyloid peptide, the major component of the amyloid plaque in Alzheimer's disease (AD). We investigated the PLA2 activity in two samples: in post-mortem brains from 23 patients with AD and 20 non-demented elderly controls, and platelets from 16 patients with a diagnosis of probable AD, 13 healthy controls and 14 elderly patients with a major depression. In AD brains PLA2 activity was significantly decreased in the parietal, and to a lesser degree in the frontal, cortex. Lower PLA2 activity correlated significantly with an earlier onset of the disease, an earlier age at death and higher counts of neurofibrillary tangles and senile plaques. In platelets PLA2 activity was also significantly reduced in the AD group as compared with healthy and depressed controls. The reduction of the enzyme activity in platelets correlated with an early disease onset and with the severity of cognitive impairment, indicating a relationship between abnormally low PLA2 activity and a more severe form of the illness. The present results provide new evidence for a disordered phospholipid metabolism in AD brains and suggest that reduced PLA2 activity may contribute to the production of amyloidogenic peptides in the disease. Further studies are needed to examine whether PLA2 activity in platelets may be useful as a peripheral marker for a subgroup of patients with AD.

Age of Onset↗
PubMed1996

[Relevance of metabolism of membrane phospholipids for Alzheimer dementia].

We found a decreased activity of the enzyme phospholipase A2 (PLA2) in brain tissue from 23 patients with Alzheimer's disease (AD) compared to 20 non-demented controls. The decrement was more pronounced in patients with an early onset of disease and correlated significantly with higher counts of senile plaques and neurofibrillary tangles. Decreased PLA2 activity may inhibit the secretion of the amyloid precursor protein (APP) and thus contribute to the formation of the beta-amyloid peptide, the major component of the amyloid plaque in AD. Because PLA2 activity is under genetic control, it is conceivable that the enzyme activity in the brain is related to the activity in blood cells. To test this assumption we investigated PLA2 in platelet membranes from AD patients compared to healthy and psychiatric controls. Platelets are interesting peripheral models in AD research, because they contain and secrete APP. We determined the platelet PLA2 activity in 16 patients with a "probable" AD (NINCDS-ADRDA criteria) as compared to 13 healthy controls and to 14 psychiatric patients with a major depression. There were no significant differences between the three groups regarding age and sex distribution. In the AD patients the cognitive performance was assessed with the CAMCOG and the Mini Mental State Exam (MMSE). The radioenzymatic assay for the determination of PLA2 activity is described elsewhere. Platelet PLA2 activity was significantly reduced in AD patients as compared to healthy (p < 0.03) and to psychiatric controls (p < 0.002). The reduction of the enzyme activity correlated with an early onset of the disease (rs = .43, p < 0.10) and with the cognitive impairment in the CAMCOG (rs = .55, p < 0.05). AD patients with a MMSE-score lower than 10 (median) showed significantly lower PLA2 activity (11.8 +/- 3.1) than patients with MMSE-score higher than 10 (16.2 +/- 4.6, p < 0.05). These findings in platelets are in line with our previous results in brain tissue. In both studies decreased PLA2 activity was related to a more severe form of AD (early onset, more cognitive impairment and higher number of plaques and tangles). Moreover, reduced platelet PLA2 activity was specific for AD as compared to age-matched psychiatric controls. Further studies should clarify whether PLA2 activity in platelets could be useful as a peripheral marker for a subgroup of AD.

Aged↗
PubMed1994

The shoulder-hand syndrome after stroke: a prospective clinical trial.

Shoulder-hand syndrome developed in 36 (27%) of 132 hemiplegic patients in a prospective study. Subluxation, paresis of the shoulder girdle, moderate spasticity, and deficits in confrontation visual field testing were the major risk factors. In a placebo-controlled, nonblinded trial, 31 of the 36 patients became almost symptom free within 10 days' treatment with low doses of oral corticosteroids. Shoulder joint capsules taken at autopsy of 7 patients showed signs of previous trauma of the affected shoulder. In the second part of this study on another 86 patients, early awareness of potential injuries to shoulder joint structures reduced the frequency of shoulder-hand syndrome from 27 to 8%. These clinical findings suggest that shoulder-hand syndrome in hemiplegia is initiated by peripheral lesions. A self-perpetuating vicious cycle may be established, followed by the clinical picture of a "reflex sympathetic dystrophy." In the majority of stroke patients, this clinical phenomenon seems to be preventable by avoiding shoulder trauma.

Adrenal Cortex Hormones↗
PubMed1994

Polymorphous high-grade B cell lymphoma is the predominant type of spontaneous primary cerebral malignant lymphomas. Histological and immunomorphological evaluation of computed tomography-guided stereotactic brain biopsies.

In this retrospective study, a series of 54 patients (1982-1989) with sporadic primary cerebral malignant lymphomas is presented. All diagnoses were uniformly done on computed tomography-guided stereotactic brain biopsies according to histological criteria and immunomorphological data. In this series, the tumors were predominantly (25 of 48; 52%) classified as polymorphous high-grade blastic B cell lymphomas. This lymphoma type is therefore regarded as the most common type of sporadic primary cerebral non-Hodgkin's lymphoma. Severe regression (++/ ), which may dramatically alter the morphological appearance of a brain lymphoma, was found in 24 of 28 (86%) of cases with glucocorticoid administration prior to stereotactic brain biopsy.

Adolescent↗
PubMed1993

Evaluation of the effect of treatment on movement disorders in astrocytomas of the basal ganglia and the thalamus.

Twenty patients with movement disorders associated with astrocytomas (grade I-IV according to the WHO tumour classification) of the basal ganglia and the thalamus were evaluated for the effects of treatment. Five patients had more than one movement disorder when the histological diagnosis was verified by stereotactic biopsy. Twelve had tremors, eight hemidystonia, three hemichorea, and one hemichorea/ballismus, and myoclonus respectively. Ten patients died during the follow up period, and for the surviving patients follow up periods ranged from 6-21 years. The movement disorders changed over long periods of time related to therapeutic interventions. CSF shunt operations and percutaneous radiotherapy had no definite effect on the movement disorders. There was a moderate response to medical treatment in a few patients. Stereotactic aspiration of tumour cysts had a marked influence on the movement disorder in two patients, and functional stereotactic surgery abolished tumour induced tremor in one. Interstitial radiotherapy was performed in fifteen patients for treatment of the underlying neoplasm and resulted in different and variable alterations of the movement disorders. These differences may be explained by complex interactions involving structures affected primarily by the tumour, as well as by secondary functional lesions of adjacent structures.

Adolescent↗
PubMed1992

Dystonia following head trauma: a report of nine patients and review of the literature.

We report nine patients who developed dystonia following head trauma. The most frequent form was hemidystonia only (six patients). One patient presented with hemidystonia plus torticollis, one with bilateral hemidystonia and one with torticollis only. Seven patients sustained a severe head injury, and two had a mild head injury. At the time of injury, six were younger than 10 years, two were adolescents, and the patient with torticollis only was an adult. Except in the patient with torticollis only, the onset of dystonia varied considerably from months to years. All patients with hemidystonia had posthemiplegic dystonia of delayed onset. Seven out of 8 patients with hemidystonia had lesions involving the contralateral caudate or putamen, as demonstrated by CT and MR. The patient with hemidystonia plus torticollis had no lesion to the basal ganglia, but a contralateral pontomesencephalic lesion. Response to medical treatment was generally poor. Functional stereotactic operations were performed in seven patients. A variety of factors may be responsible for the vascular or nonvascular posttraumatic basal ganglia lesions, which may lead to dystonia. The pathophysiology seems to be more complex than thought previously. We believe that dystonia following head injury is not as rare as is assumed. Awareness of its characteristics and optimized diagnostic procedures will lead to wider recognition of this entity.

Adult↗
PubMed1992

CT-stereotactic fibrinolysis of spontaneous intracerebral hematomas.

CT-stereotactic fibrinolysis is an effective alternative to surgical and conservative therapies for intracerebral hematoma. The method consists of stereotactically puncturing and partially evacuating the hematoma. After fibrinolysis using urokinase, the residual hematoma is completely evacuated through a catheter inserted in the cavity of the hematoma. The operation is usually performed under local anesthesia. Stereotactic methods are safer and less invasive than other methods. Since October 1985, a total of 85 patients have been treated with this method in the Department of Stereotaxy and Neuronuclear Medicine at the University of Freiburg Medical School. Although 25 patients died (29.4%) during the mean follow-up period of 20 months, only 16 (18.8%) died in the acute postoperative phase or within the first 60 days after evacuation. Eighteen patients (21.2%) had died six months after the operation. The quality of life of the 60 surviving patients, as measured on the Karnofsky Scale at follow-up, was very good to good in 70% and moderate in 23.3%. Only 6.7% of the patients were so disabled that they required special care and assistance or had to be placed in a nursing home. The long-term results are thus very encouraging.

Cause of Death↗
PubMed1992

Primary cerebral malignant non-Hodgkin's lymphomas: a retrospective clinical study.

In this retrospective study a series of 54 patients (seen from 1982 to 1989) with sporadic primary cerebral malignant lymphomas (PCML), which were uniformly classified with the support of immunocytochemical data, is presented. The analysis shows that on CT PCML are shown as cirumscribed, homogeneous, contrast-enhanced multifocal (70%) or solitary (30%) mass lesions within the subcortical white matter; they were found mainly close to the ventricular system or the subarachnoid space. To prove the histological diagnosis and for the purposes of differential diagnosis, low-risk CT-stereotactic biopsy is necessary and is the method of choice. Immunomorphological techniques are valuable adjuncts to confirm the histological diagnosis of PCML. In the series presented these tumours have been predominantly classified as high-grade blastic B-cell lymphomas. For this reason, this type should be regarded as the prevalent variant of malignant brain lymphomas. The evaluation of possible prognostic factors suggests that age at admission and morphological features of regression are relevant determinants of survival time. A correlation between neuroradiological evidence of a decrease in tumour size, morphological signs of regression and glucocorticoid administration has been found. Thus, patients suspected of having PCML require rapid diagnosis prior to corticosteroid administration. PCML have been shown to be radioresponsive, but not curable. Because of the lack of uniformity in management of this rate brain neoplasm, the different treatment protocols are not comparable, and hence the optimum therapy has not been satisfactorily determined.(ABSTRACT TRUNCATED AT 250 WORDS)

Actuarial Analysis↗
PubMed1991

Long-term outcome of 89 low-grade brain-stem gliomas after interstitial radiation therapy.

Between 1974 and 1985, 89 patients suffering from histologically confirmed, nonresectable low-grade astrocytomas located in the brain stem were entered into a retrospective study. Iodine-125 (125I) was implanted in 29 patients and iridium-192 (192Ir) in 26 patients. Computerized tomography revealed that 78% of the tumors in these patients were located chiefly in the mesencephalic region, 70% were circumscribed, and 78% were contrast-enhanced. Thirty-four patients underwent biopsy without prior aggressive tumor-specific therapy such as chemotherapy or external beam irradiation. Among these, 70% of the tumors were located predominantly in the pons, 74% were diffuse, and 59% were hypodense or isodense after contrast enhancement. Long-term follow-up investigations indicated that life expectancy after interstitial radiation therapy with 125I implanted directly by catheter either permanently or temporarily showed a more favorable trend than that after treatment with 192Ir. Interstitial radiation therapy with 125I appears to be an effective treatment for slowly proliferating, differentiated, well-delineated, nonresectable brain-stem gliomas. This technique makes it possible to achieve radiosurgical tumor control and, when carefully applied, represents the least traumatic treatment. Reduction of the tumor mass brings about improvement of the clinical symptoms. Further investigations on the biological behavior of brain-stem gliomas and prospective randomized long-term follow-up studies are necessary to evaluate the different kinds of treatment available for these patients.

Adolescent↗
PubMed1991

[Stereotactic evacuation and early rehabilitation in space-occupying cerebral hemorrhage].

The choice of treatment in intracerebral hematoma remains controversial as long as there are no prospective, randomized trials from multiple centers. Recent experiences showed a lower mortality rate after stereotactic evacuation of intracerebral hematoma. However according to the present study (60 patients) the quality of survival and duration of hospital stay seems to be dependent on early and intensified rehabilitation and physiotherapy.

Cerebral Hemorrhage↗
PubMed1989

[The significance of stereotaxic brain biopsy in atypical multiple sclerosis].

Multiple sclerosis (MS) is one of the most common diseases of the central nervous system. Up to now, there is no pathognomonic test to ascertain the diagnosis and in 10 to 15% of MS cases there are problems in differential diagnosis. We report 15 bioptically diagnosed MS cases with atypical clinical, C.S.F. and neuroradiological findings. In each case the diagnosis of MS was made by CT/MRI-stereotactic brain biopsy. Neoplastic and other non-tumorous lesions could be excluded. Indications for and significance of stereotactic brain biopsy in atypical cases of MS are discussed.

Adult↗
PubMedDate not supplied

The value of REM sleep parameters in differentiating Alzheimer's disease from old-age depression and normal aging.

Pseudodementia as a common trait in elderly depressives presents a major problem in gerontopsychiatry, especially for the differential diagnosis between Old-Age Depression (OAD) and Dementia of the Alzheimer Type (DAT). The present polysomnographic study examined parameters of sleep continuity, sleep architecture, and REM sleep to differentiate DAT from OAD. The investigation was based on the theoretical framework of the cholinergic-aminergic imbalance model of depression, the cholinergic deficit hypothesis of Alzheimer's disease and the reciprocal interaction model of Non-REM/REM sleep regulation, according to which REM sleep parameters should have high discriminative value to differentiate OAD and DAT. We investigated 35 DAT patients, 39 OAD patients and 42 healthy controls for two consecutive nights in the sleep laboratory. The DAT patients were in relatively early/mild stages of the disease, the severity of depression in the OAD group was moderate to severe. Depressed patients showed characteristic 'depression-like' EEG sleep alterations, i.e. a lower sleep efficiency, a higher amount of nocturnal awakenings and decreased sleep stage 2. Sleep continuity and architecture in DAT was less disturbed. Nearly all REM sleep measures differentiated significantly between the diagnostic groups. OAD patients showed a shortened REM latency, increased REM density and a high rate of Sleep Onset REM periods (SOREM), whereas in DAT REM density was decreased in comparison to control subjects. REM latency in DAT was not prolonged as expected. To assess the discriminative power of REM sleep variables a series of discriminant analyses were conducted. Overall, 86% of patients were correctly classified, using REM density and REM latency measures. Our findings suggest that REM density as an indicator of phasic activity appears to be more sensitive as a biological marker for the differential diagnosis of OAD and DAT than REM latency. The results support the role of central cholinergic neurotransmission in REM sleep regulation and the pathogenesis of DAT and OAD.

Aged↗