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Biomedical subjects

S Evers

Publications and source records attributed to S Evers.

At least 91 records · Page 5Linked to original sources
PubMed2000

[Differential diagnosis and therapy of headache in HIV infection].

UNLABELLED: HEADACHE AND HIV INFECTION: Headache is one of the most common pain syndromes in HIV infection. The prevalence of headache in HIV infected patients in the published cross-sectional and longitudinal studies is between 3.8% and 47.4% depending on the study methodology and the study subpopulation. In this review, we analyse these cross-sectional and longitudinal studies and the case reports of headache in HIV infection. Both primary headache, such as migraine or tension-type headache, and secondary headache, e. g. caused by opportunistic infections or neoplasms, can be observed. In addition, there is a so-called "HIV headache" which develops de novo during the HIV infection, the cause of this headache type is still unclear. Migraine shows an amelioration during the course of the HIV infection whereas tension-type headache shows a deteriotation. In some patients, however, tension-type headache cannot be differentiated from HIV-headache. THERAPY: The therapeutic management of headache during the HIV infection is the same as in non-infected subjects. However, tricyclic antidepressants and steroids as headache prophylactic agents are often more effective than in non-infected subjects and should be prescribed more generously. Some pharmacological interactions have to be considered, e. g. NSAID might increase the toxicity of antiretroviral substances.

English Abstract↗
PubMed2000

The impact of HIV infection on primary headache. Unexpected findings from retrospective, cross-sectional, and prospective analyses.

Headache is one of the most important factors influencing the quality of life in patients infected with the human immunodeficiency virus type 1 (HIV). However, only symptomatic headache but not changes or primary headache types during HIV infection have been studied to date. Therefore, we aimed to determine the impact of an HIV infection on frequency and semiology of different primary headache types. Patients with confirmed HIV type 1 infection underwent a neurological examination, neuroimaging or EEG, and a standardized interview. Time pattern and symptoms of headaches (cross-sectional analysis), changes of headaches preexisting to their infection (longitudinal retrospective analysis), and changes of primary headaches during a 2-year follow-up (longitudinal prospective analysis) were evaluated as were the correlations between these headache patterns and different markers of HIV infection. One hundred thirty-one consecutive HIV-infected patients without evidence of a cerebral manifestation except mild encephalopathy were enrolled. The point prevalence of migraine was 16.0% (confidence interval (CI) 10.1-25.4%), of headache with a semiology of tension-type headache 45.8% (CI 33.7-62.2%), and of other headache types 6.1% (CI 3.0-12.5%). During the natural course of infection, the migraine frequency significantly decreased in the retrospective and in the prospective analyses, whereas the frequency of the headache with a semiology of tension-type headache significantly increased in all three analyses. In 20% of all patients, the tension-type headache could be considered as symptomatic due to the infection but not due to focal or general cerebral lesions. Changes of primary headache were significantly associated with different stages of the infection and with the presence of mild encephalopathy but not with antiretroviral treatment or CD4 cell count. HIV infection seems to be associated with a progressive decrease in migraine frequency and intensity which probably is related to the immunological state of the patients. Tension-type headache becomes more frequent during HIV infection. However, this can in part be related to secondary headache caused by the HIV in less than 50% of patients with tension-type headache. The progressing immunological deficiency of HIV-infected patients seems to influence pain processing of primary headache types in different ways.

Adult↗
PubMed2000

Screening for HIV-associated distal-symmetric polyneuropathy in CDC-classification stages 1, 2, and 3.

OBJECTIVES: A total of 670 patients were screened for distal symmetric HIV-associated polyneuropathy during CDC stages 1-3 and its correlation to immunological deterioration. MATERIAL AND METHODS: Clinical examinations of 670 patients admitted to the neurological outpatient clinic at the Department of Neurology, University of Munster. Neurophysiological investigations were performed on the sural and peroneal nerve for detection of axonal and myelin lesion. RESULTS: Clinical examination proved progressive clinical signs and symptoms indicating distal symmetric polyneuropathy from CDC 1 (32%) to CDC 3 (55%). At least one neurophysiological result was impaired in CDC 1 in 25% and in CDC 3 in 45%. Significant correlation between neurophysiological changes and CDC4(+)-cells and beta-microglobuline were detected for stage CDC 3 C. CONCLUSION: Results show stage related prevalence of distal symmetric polyneuropathy already in early stages. In late stages of HIV-infection prevalence of distal symmetric polyneuropathy seems to be directly correlated to immunodeficiency syndrome. The pathogenesis of distal symmetric polyneuropathy during HIV-infection is up to now incompletely understood, but results indicate a clear dependency between progressive immunological dysfunction and neuropathy. High active antiretroviral therapy in patients suffering from distal symmetric polyneuropathy is a main topic of future studies.

Adult↗
PubMed2000

Anaerovorax odorimutans gen. nov., sp. nov., a putrescine-fermenting, strictly anaerobic bacterium.

The strictly anaerobic, gram-positive, non-spore-forming bacterium strain NorPut1T ferments putrescine to acetate, butyrate, molecular hydrogen and ammonia. It also utilizes 4-aminobutyrate and 4-hydroxybutyrate as growth substrates. Comparative 16S rDNA sequence analysis confirmed a phylogenetic affiliation of this strain to the phylum of gram-positive bacteria with low DNA G+C content. Together with its closest relative, 'Clostridium aminobutyricum' (DSM 2634), and several Eubacterium species, strain NorPut1T represents a well-defined monophyletic group. Moderate overall 16S rRNA sequence similarities (< 91%) were found for the NorPut1T/'Clostridium aminobutyricum' pair and several Eubacterium species. The type species, Eubacterium limosum, is not a member of the group and, together with Eubacterium barkeri and Pseudoramibacter alactolyticus, represents a distant phylogentic cluster. Therefore, a new genus, Anaerovorax, is proposed as harbouring strain NorPut1T (= DSM 5092T), which is described as a new species, i.e. Anaerovorax odorimutans.

Acetates↗
PubMed1999

Cognitive processing is involved in cluster headache but not in chronic paroxysmal hemicrania.

BACKGROUND: Cognitive processing in migraine is characterized by a loss of habituation during the interval and increased latencies in an attack. No studies are available on event-related potentials (ERPs) in cluster headache or chronic paroxysmal hemicrania. OBJECTIVE: To determine the involvement of cognitive processing in cluster headache and chronic paroxysmal hemicrania as measured by ERPs. METHODS: Visually evoked ERPs were measured in 50 patients with episodic cluster headache, 11 patients with chronic cluster headache, and 12 patients with chronic paroxysmal hemicrania. Measurements were performed in the cluster period outside an attack with and without prophylactic medication and not in the cluster period. RESULTS: Latencies of the endogenous ERP components were significantly increased during the cluster period as compared with outside the cluster period and with healthy subjects. In chronic cluster headache, latencies of both endogenous and exogenous components were increased. Medication with prophylactic drugs normalized the ERP latencies in episodic cluster headache; in chronic cluster headache, ERP latencies were decreased without complete normalization. No changes of ERP latencies and amplitudes could be observed in chronic paroxysmal hemicrania. A loss of cognitive habituation as it is known in migraine could not be observed in either cluster headache or chronic paroxysmal hemicrania. CONCLUSIONS: Our data suggest that central structures generating ERPs are involved in the pathophysiology of cluster headache during the cluster period but not outside the cluster period. This is in concordance with recent neuroimaging findings on the central role of the hypothalamus and the right frontal cortex in cluster headache and supports the hypothesis of a central origin of cluster headache. Furthermore, the data suggest that cluster headache and chronic paroxysmal hemicrania are distinct entities.

Adult↗
PubMed1999

Metabolic characterization of AIDS dementia complex by spectroscopic imaging.

Prospective proton chemical shift imaging (CSI) of the brain was performed in 30 HIV- 1-seropositive patients and 11 healthy controls. Significant (P < 0.05) reductions in the N-acetyl-L-aspartate (NAA)/total creatine (Cr), and NAA/total choline (Cho) ratios and significant increases in Cho/Cr occurred in patients with 1) AIDS-defining diagnoses; 2) <200 CD4 lymphocyte counts/microl; 3) neurological evidence for an AIDS dementia complex (ADC); 4) magnetic resonance imaging (MRI) signs of cerebral atrophy. The basal ganglia and the insula were affected to approximately the same extent and without indications of spatial variations within these areas. Reduced NAA seems to indicate progressive neuronal injury or loss due to productive HIV infection in the brain and its clinical picture ADC. Spectroscopic abnormalities were, however, also observed in neurologically normal HIV patients or those with normal MRI results. Proton CSI may therefore serve as an early quantitative marker of central nervous system involvement in AIDS.

AIDS Dementia Complex↗
PubMed1999

[Psychosocial handicap due to chronic headaches. Evaluation of the inventory of Disabilities caused by Headache].

Chronic primary headache has a considerable impact on the quality of life. To date, this impact has been evaluated by measurements of the general pain specific impairment of the quality of life. Headache specific measurements of quality of life or of disability caused by the headache are still missing for the German language. In America, a headache specific questionnaire, the "Headache Disability Inventory" (HDI), has been evaluated which is used in the presented study to create a German version, the "Inventar zur Beeinträchtigung durch Kopfschmerzen" (IBK). 94 consecutive patients with a primary headache disorder (59 female, 35 male; mean age 40 +/- 12 years) were examined. Cronbach's alpha was a = 0.90, the test-retest-reliability after three months was r = 0.87. An analysis of subscales for emotional and functional disability showed similar values for the internal consistency and the test-retest-reliability of these subscales. The scores of the different headache types did not differ significantly. In post-hoc-analyses, however, cluster headache showed higher disability scores than migraine both in the total scale and in the subscales. The total score of the IBK was significantly correlated with the number of headache days per month (r = 0.41; p < 0.0003) but not with the duration of disease or other demographic parameters. The IBK is the first German headache specific measurement of certain aspects of the quality of life in chronic headache patients. It can be used in clinical settings to evaluate the current state of the patient or to monitor treatment and it can be used for scientific studies.

Adult↗
PubMed1999

[Cryptococcal meningoencephalitis in HIV infected immigrants. Diagnostic and therapeutic aspects with reference to evidence-based medicine"--an overview].

Cryptococcal meningitis is one of the most frequent forms of meningoencephalitis in AIDS patients. Before the introduction of triazole antibiotics like difluconazole, the frequency of this meningitis among AIDS patients was 5-10%, yet declined during the last years. Clinically, nonspecific signs of a meningeal inflammation predominate while focal neurological signs are rare. Rapid institution of high-dose antimycotic therapy is the keystone to improve prognosis and decrease mortality. Antimycotics of choice are amphotericin B, fluconazole, and flucytosin. Diagnosis is established by detection of cryptococcal antigen in cerebrospinal fluid, microscopic demonstration of cryptococci using India-ink, and cryptococcal cultures. Recent developments aim to improve antimycotic therapies. During the last years, lifelong secondary prevention with difluconazole was established. Cryptococci which are resistant against fluconazole and amphotericin B are a special challenge, yet fortunately are rare. Longterm outcome of patients is determined by the progression of the underlying immunosuppression. Therefore, combination of secondary prophylaxis with modern antiviral substances is important. Clinical decision analysis in patients with suspected cryptococcal meningitis is presented using methods from evidence-based medicine.

AIDS-Related Opportunistic Infections↗
PubMed1999

The impact of ergotamine-induced headache and ergotamine withdrawal on information processing.

Ergotamine abuse and subsequent ergotamine-induced headache is a common problem in the pharmacological treatment of migraine and other headache types; often, withdrawal therapy is necessary. This study investigated whether ergotamine abuse affects information processing and whether withdrawal therapy can lead to an improvement of information processing. We designed a standardized neurophysiological retrospective (ergotamine abuse) and prospective (ergotamine withdrawal) study in a supraregional headache outpatient clinic. Seventy-one patients abusing ergotamine derivatives with subsequent daily headache were enrolled and compared to 36 migraine patients without ergotamine intake and 36 healthy subjects. Information processing was evaluated by latencies and amplitudes of visually evoked event-related potentials (ERP) before and after ergotamine withdrawal therapy. P3 latency of the ERP was significantly increased in ergotamine abuse (442 +/- 45 ms) versus migraine (415 +/- 40 ms) and healthy subjects (410 +/- 33 ms), there was no difference between ergotamine tartrate and dihydroergotamine abuse. The migraine specific loss of habituation in information processing as measured by P3 latency could not be observed in migraine patients with ergotamine abuse. After successful withdrawal therapy in 36 patients, the abnormally prolonged P3 latency was significantly shortened (452 +/- 47 ms versus 433 +/- 30 ms; P < 0.004). Our findings imply that information processing is impaired by ergotamine abuse and can be improved but not normalized after withdrawal therapy. Furthermore, our data provide strong evidence that ergotamine, besides its peripheral effects, has a central mode of action.

Adrenergic alpha-Agonists↗
PubMed1999

A retrospective long-term analysis of the epidemiology and features of drug-induced headache.

Drug-induced headache is well known to result from the abuse of compounds taken for the treatment of primary headache. The features of drug-induced headache depend on various features including the availability of drugs, the regional health system, and psychogenic factors of the patients. We performed a retrospective study on a series of 257 consecutive German patients presenting with drug-induced headache during the period 1983-1996. Our aim study was to evaluate the demographic features, the frequency of various drugs used, in particular of ergotamine derivates, and changes in these features during the study period. The frequency of drug-induced headache among all headache patients was 8%, with a female preponderance of 81%. Drug-induced headache occurred in all age groups, predominantly in migraine patients (35%). The mean number of substances used was 2.7, mainly, acetaminophen (47.9%), ergotamine tartrate (45%), and combined analgesics (56%). We did not find a significant difference between the associations with ergotamine tartrate and dihydroergotamine, although the latter was taken less frequently. Comparing the early and late years of our study period, there were no changes in the frequency of drug-induced headache (8% versus 7%), although changes in the frequency of some drugs changed (barbiturates, ergotamine tartrate, and codeine intake decreased whereas nonsteroidal anti-inflationary drugs, combined analgesics, and sumatriptan intake increased). Our data suggest that changes in drug availability and the introduction of classification criteria and treatment recommendations did not have a major impact on the frequency of drug-induced headache.

Adult↗
PubMed1999

Influence of cytotoxicity enhancers in combination with human serum on the activity of CD22-recombinant ricin A against B cell lines, chronic and acute lymphocytic leukemia cells.

Despite the strong in vitro activity of some immunotoxins (ITs), clinical application did not result in complete cure. The outcome of therapy may be improved by combining ITs with IT-cytotoxicity enhancing agents. We studied the effect of various agents that influence the intracellular routing of ITs on the activity of the anti-B cell IT CD22-recombinant (rec) ricin A. In protein synthesis inhibition assays the carboxylic ionophores monensin and nigericin enhanced the activity of the IT 117- and 382-fold, respectively, against the cell line Daudi, and 81- and 318-fold, respectively, against the cell line Ramos. IT activity to Daudi and Ramos was enhanced to a lesser extent by the lysosomotropic amines chloroquine (14- and 11-fold, respectively) and NH4Cl (nine- and 10-fold, respectively). However, the combination of NH4Cl and chloroquine induced more than an additive effect (145- and 107-fold, respectively). Cytotoxicity was not influenced by brefeldin A, all-trans retinoic acid (ATRA), verapamil and perhexiline maleate. Bacitracin enhanced the IT cytotoxicity in contrast to the other protease inhibitors aprotinin, leupeptin and soybean trypsin inhibitor, albeit enhancement was weak (two-fold). The enhancers exerted only a negligible effect on bone marrow progenitor cells. We recently developed a flow cytometric cytotoxicity assay in which cell elimination can be assessed. In order to detect enhancement in this assay, we used 5 x 10(-11) M IT (approximately the 50% protein synthesis inhibiting dose (ID50)). This concentration killed 41% of the Daudi cells and 42% of the Ramos cells. In the presence of 10 nM monensin the IT killed 74% and 99% and in the presence of 10 nM nigericin 96% and 99% of the Daudi and Ramos cells, respectively. At 10(-8) M, CD22-rec ricin A eliminated malignant cells originating from three patients with B-CLL (0.42 log) and two with B-ALL (0.19 log) patients. Cytotoxicity to malignant cells was enhanced by NH4Cl, chloroquine, monensin and nigericin. The combination of NH4Cl and chloroquine enhanced the activity most effectively (up to 2.06 log). To determine the applicability of the IT in combination with enhancers in vivo we investigated the effect of human serum. Human serum inhibited IT activity which could not be restored by monensin and nigericin because of complete inhibition of these enhancers by serum. In contrast, chloroquine partially restored the activity of CD22-rec ricin A in the presence of human serum. We conclude that monensin, nigericin and the combination of NH4Cl and chloroquine can be used instead of NH4Cl to potentiate CD22-rec ricin A activity in purging autologous bone marrow transplants contaminated with malignant B cells. Chloroquine might be a promising enhancer of CD22-rec ricin A for treating patients in vivo.

Antigens, CD↗
PubMed1999

Dynamic changes of cognitive habituation and serotonin metabolism during the migraine interval.

Migraine patients show a specific cognitive processing with a loss of habituation in the interval and a normal habituation in the attack as measured by event-related potentials (ERPs). It is unknown whether the loss of habituation changes during the migraine interval or is a stable state. Serotonin (5HT) metabolism is involved in the pathophysiology of migraine and also in the generation of ERPs. We enrolled 14 patients with regular migraine attacks in order to measure visually evoked ERPs repetitively during the migraine interval and in the migraine attack. Cognitive habituation was evaluated by analysis of P3 latency. Platelet serotonin content and free serotonin plasma level were measured at the same time points. The loss of habituation increased continuously during the migraine interval and abruptly normalized in the migraine attack (p < 0.05, time series analysis). The platelet 5HT content decreased significantly in the migraine attack (p < 0.03) and was at its maximum in the middle of the interval. The P3 latency was significantly increased in the attack (p < 0.01) and was significantly inversely correlated with the platelet 5HT content (r = -0.44, p < 0.001). Free 5HT plasma levels did not show any significant change. Our findings suggest that loss of cognitive habituation continuously increases during the migraine interval until its normalization in the migraine attack. This phenomenon cannot be attributed to serotonergic transmission. In patients with regular changes of cognitive habituation before the migraine attack, it might be possible to predict the attack by analysing ERPs.

Adult↗
PubMed1999

Coincidence of familial hemiplegic migraine and hemicrania continua? A case report.

A case is presented of a 39-year-old woman with a history of simultaneous Familial hemiplegic migraine (FHM) and hemicrania continua (HC). The family history of the patient revealed different types of migraine and cyclic syndromes in childhood in four generations. The possible links between FHM and HC are discussed. The pedigree gives further evidence that cyclic syndromes in childhood belong to the spectrum of migraine.

Adult↗
PubMed1999

Piracetam and platelets--a review of laboratory and clinical data.

This paper reviews the effects of piracetam on platelet function and the evidence for its antiplatelet effect which is mediated mainly by inhibition of platelet aggregation. Piracetam also possesses antithrombotic activity in vivo. It has been shown to normalize platelet aggregation in patients with increased platelet aggregability in various disorders including acute stroke, transient cerebral ischemic attacks and diabetes mellitus. This, together with clinical improvement, has also been shown in patients with Raynaud's phenomenon. The results of recent studies are presented in which piracetam showed similar efficacy to aspirin in the secondary prophylaxis of ischemic stroke.

Blood Platelets↗
PubMed1999

The cerebral haemodynamics of music perception. A transcranial Doppler sonography study.

The perception of music has been investigated by several neurophysiological and neuroimaging methods. Results from these studies suggest a right hemisphere dominance for non-musicians and a possible left hemisphere dominance for musicians. However, inconsistent results have been obtained, and not all variables have been controlled by the different methods. We performed a study with functional transcranial Doppler sonography (fTCD) of the middle cerebral artery to evaluate changes in cerebral blood flow velocity (CBFV) during different periods of music perception. Twenty-four healthy right-handed subjects were enrolled and examined during rest and during listening to periods of music with predominant language, rhythm and harmony content. The gender, musical experience and mode of listening of the subjects were chosen as independent factors; the type of music was included as the variable in repeated measurements. We observed a significant increase of CBFV in the right hemisphere in non-musicians during harmony perception but not during rhythm perception; this effect was more pronounced in females. Language perception was lateralized to the left hemisphere in all subject groups. Musicians showed increased CBFV values in the left hemisphere which were independent of the type of stimulus, and background listeners showed increased CBFV values during harmony perception in the right hemisphere which were independent of their musical experience. The time taken to reach the peak of CBFV was significantly longer in non-musicians when compared with musicians during rhythm and harmony perception. Pulse rates were significantly decreased in non-musicians during harmony perception, probably due to a specific relaxation effect in this subgroup. The resistance index did not show any significant differences, suggesting only regional changes of small resistance vessels but not of large arteries. Our fTCD study confirms previous findings of right hemisphere lateralization for harmony perception in non-musicians. In addition, we showed that this effect is more pronounced in female subjects and in background listeners and that the lateralization is delayed in non-musicians compared with musicians for the perception of rhythm and harmony stimuli. Our data suggest that musicians and non-musicians have different strategies to lateralize musical stimuli, with a delayed but marked right hemisphere lateralization during harmony perception in non-musicians and an attentive mode of listening contributing to a left hemisphere lateralization in musicians.

Adult↗
PubMed1999

Drug-induced headache: long-term results of stationary versus ambulatory withdrawal therapy.

Drug-induced headache is a well-known complication of the treatment of primary headache disorders, and its successful management is only possible by withdrawal therapy. However, it is unknown whether ambulatory or stationary withdrawal is the therapy preferred. We conducted a prospective study on the outcome of stationary versus ambulatory withdrawal therapy in patients with drug-induced headache according to the International Headache Society criteria. Out of 257 patients with the diagnosis of drug-induced headache during the study period, 101 patients (41 after ambulatory and 60 after stationary withdrawal therapy) could be followed up for 5.9 +/- 4.0 years. The total relapse rate after successful withdrawal therapy was 20.8% (14.6% after ambulatory and 25.0% after stationary withdrawal therapy, p < 0.2). The main risk factors for a relapse were male sex (OR = 3.9, CI = 1.3-11.6), intake of combined analgesic drugs (OR = 3.8, CI = 1.4-10.3), administration of naturopathy (OR = 6.0, CI = 1.2-29.3), and a trend to tension-type headache as the primary headache disorder (OR = 1.9, CI = 0.6-53.0). Our data suggest that neither the method of withdrawal therapy nor the kind of analgesic and other antimigraine drugs has a major impact on the long-term result after successful withdrawal therapy. Patients with risk factors according to our findings should be informed and monitored regularly, and combined drugs should be avoided. Furthermore, our data suggest that there is a need for research on individual psychological and behavioral risk factors for relapse after successful withdrawal therapy in drug-induced headache.

Adult↗
PubMed1999

Cerebral vasculopathy in HIV infection revealed by transcranial Doppler: A pilot study.

BACKGROUND AND PURPOSE: There is growing evidence for affection of cerebral vessels during human immunodeficiency virus (HIV) infection. We prospectively evaluated cerebrovascular reserve capacity (CRC) in HIV-seropositive patients by transcranial Doppler sonography (TCD) after systemic administration of acetazolamide. We hypothesized that a disturbed vasoreactivity would reflect the cerebral arteries' involvement in HIV infection. METHODS: We assessed the mean blood flow velocity (BFV) of the middle cerebral artery and its increase after intravenous administration of 1 g acetazolamide (CRC) in 31 HIV-infected individuals without symptoms of cerebrovascular disease (mean+/-SD age, 39+/-11 years). Stenotic or occlusive lesions of the large brain-supplying arteries were excluded by color-coded duplex and transcranial imaging. BFV and CRC were also measured in an age-matched group of 10 healthy control subjects. Patients were classified according to clinical, laboratory, and neurophysiological parameters. We also performed cerebral MRI (n=25) and rheumatological blood tests (n=26). RESULTS: Baseline BFV and CRC both were significantly reduced in HIV-infected patients as compared with control subjects (P<0.05, Student's t test). These findings did not correlate with duration of seropositivity, helper cell count, or other clinical, rheumatological, and neuroradiological findings. CONCLUSIONS: Our findings support the hypothesis of a cerebral vasculopathy etiologically associated with HIV infection.

AIDS Dementia Complex↗