Biomedical subjects

D Bereczki

Publications and source records attributed to D Bereczki.

At least 19 recordsLinked to original sources

PubMed2002

The Mureş-Uzhgorod-Debrecen study: a comparison of hospital stroke services in Central-Eastern Europe.

Stroke mortality is extremely high in Central-Eastern European countries. The high rate of risk factors and differences in health care services might be among the factors resulting in high stroke morbidity and mortality in this region. As only few prospectively collected information are available from this region, we decided to evaluate some characteristics of stroke services in neurological departments of a Romanian, a Ukrainian and a Hungarian city in the framework of the Mureş-Uzhgorod-Debrecen comparative epidemiological study. We registered demographic data, the absence or presence of the most important risk factors, and clinical signs on admission and at discharge. We recorded the application of various diagnostic methods, stroke treatment and recommendations for secondary prevention. Follow-up is planned after 30 days and after 1 year. The paper summarizes the methodology of this prospective epidemiological study of stroke patients hospitalized in neurological departments in Târgu Mureş, Uzhgorod and Debrecen, three Central-Eastern European cities in Romania, Ukraine and Hungary, respectively.

Follow-Up Studies↗

PubMed2001

[The effect of a single-dose intravenous vinpocetine on brain metabolism in patients with ischemic stroke].

The effect of a single-dose i.v. infusion of vinpocetine on the cerebral blood flow (CBF) and glucose metabolism of post-stroke patients was studied by measuring the regional and global cerebral metabolic rates of glucose (CMRglu) and the corresponding kinetic constants before and after treatment. Transcranial Doppler (TCD) and single photon emission tomography (SPECT) measurements were also performed. The cerebral glucose metabolism was significantly higher in the contralateral hemisphere than in the affected one before therapy. In the affected hemisphere the regional glucose metabolism was inhomogenous: relatively low values were measured in the stroke region, whereas it was increased in the peristroke region. Although a single-dose vinpocetine treatment did not affect significantly the regional or global metabolic rates of glucose, the glucose transport (both intracellular up-take and release) was strongly affected in the whole brain, in the contralateral hemisphere and in the peri-infarct area of the symptomatic hemisphere. A slightly increased (not significant, N. S.) cerebral blood flow could be observed in the contralateral and a decreased flow (N. S.) in the symptomatic hemisphere.

Aged↗

PubMed2001

Mannitol for acute stroke.

BACKGROUND: Mannitol is an osmotic agent and a free radical scavenger so it might decrease oedema and tissue damage in stroke. OBJECTIVES: To test whether treatment with mannitol reduces short and long-term case fatality and dependency after acute ischaemic stroke or cerebral parenchymal haemorrhage. SEARCH STRATEGY: We searched the Cochrane Stroke Group Specialised Trials Register. In addition to this, supplementary MEDLINE searches were performed. The Chinese Stroke Trials Register was checked and the Latin-American databank LILACS was searched with the search term MANNITOL and its variations in the Portuguese and Spanish languages. A search was performed of Masters and Ph.D. degree theses in the databank of Sao Paulo University, and in abstracts of medical congresses on neurology and neurosurgery from 1965 to 1997 in Brazil. SELECTION CRITERIA: Truly randomised unconfounded clinical trials comparing the effect of mannitol with placebo or open control in patients with acute ischaemic stroke or parenchymal haemorrhage were eligible for inclusion. DATA COLLECTION AND ANALYSIS: Two reviewers independently selected the trials to be included in the review. After reaching an agreement on which trials to include, two of the reviewers extracted data from the trials and performed the data analysis. Accuracy of data extraction was checked by comparing the results. Included trials were tabulated for methodological quality including the method of randomisation and blinding, and stating if CT was performed, if patients were lost to follow-up and if intention-to-treat analysis was performed. Data synthesis and analysis was performed using the Cochrane Review Manager software. MAIN RESULTS: Only one trial fulfilled the inclusion criteria. The number of included patients was small (36 treated and 41 controls) and the follow up was short. Neither beneficial nor harmful effects of mannitol could be proved. Case fatality, the proportion of dependent patients at the end of the follow up and side effects were not reported and were not available from the investigators. The planned outcome analyses and sensitivity analyses could not be performed due to lack of appropriate trials. REVIEWER'S CONCLUSIONS: There is currently not enough evidence to decide whether the routine use of mannitol in acute stroke would result in any beneficial or harmful effect. The routine use of mannitol in all patients with acute stroke is not supported by any evidence from randomised controlled clinical trials. Further trials are needed to confirm or refute the routine use of mannitol in acute stroke.

Acute Disease↗

PubMed2001

Lack of gender difference in acetazolamide-induced cerebral vasomotor reactivity in patients suffering from type-1 diabetes mellitus.

The aim of the present work was to investigate the impact of gender on resting cerebral blood flow velocity and cerebrovascular reserve capacity among diabetic patients. Middle cerebral artery mean blood flow velocity (MCAV) was measured in 72 patients suffering from type 1 diabetes mellitus at rest and 5, 10, 15 and 20 min after intravenous administration of 1 g acetazolamide. Cerebrovascular reserve was calculated as the maximal percent increase in MCAV after acetazolamide. Resting MCAV and cerebrovascular reserve capacity were compared between males and females. Resting cerebral blood flow velocity was higher in diabetic females than in males (men, 55.0+/-17.0 cm/s; women, 64.4+/-12.6 cm/s, p=0.0094). Cerebrovascular reserve capacity was similar in diabetic women and men (men, 44.0%+/-18.6%; women, 52.6%+/-32.9%, p=0.17). Comparing MCAV and cerebrovascular reserve capacity among the diabetic subgroups with disease duration < or = 10 years and >10 years, we did not detect any differences between women and men. Duration of diabetes was an important factor in determining cerebrovascular reserve capacity in both sexes: long-term diabetic women and men showed lower CRC values than diabetics with < or = 10 years disease duration. Cerebrovascular reserve capacity is similar in diabetic women and men. Taking into consideration that cerebrovascular reserve is normally higher among women, our finding indicates a relatively more serious worsening of cerebral vasodilatory responses in women suffering from type 1 diabetes.

Acetazolamide↗

PubMed2001

A possible role of decreased oxidative resistance of low-density lipoproteins in the early formation of carotid atherosclerosis.

Ischaemic stroke ranks among the most important causes of death and disability in developed countries. Abnormal lipid metabolism is among the several factors that have a role in the pathogenesis of atherosclerosis. We hypothesize that the decreased resistance of low-density lipoproteins against oxidative stress is an independent risk factor for cerebral atherosclerosis and suggest testing this hypothesis by ultrasonographic evaluation of the carotid artery and correlating this finding to plasma values of compounds that play a role in lipid metabolism. By measuring the oxidative resistance of low-density of lipoprotein the risk for ischaemic stroke can be predicted.

Carotid Artery Diseases↗

PubMed2001

Transcranial Doppler monitoring in hypertensive patients during physical exercise.

PURPOSE: To evaluate the diagnostic value of a combined method, i.e. ergometer cycling with continuous bilateral transcranial Doppler monitoring (TCD) to detect cerebral hemodynamic abnormalities in recently diagnosed hypertensive patients. METHODS: 30 neurologically symptom-free, nontreated patients with essential hypertension and 30 age- and sex-matched controls were studied. Carotid ultrasound, resting ECG and blood parameters were investigated. Cycling ergometry was performed according to the WHO protocol. Blood pressure, heart rate, end-tidal CO2 (etCO2) and bilateral middle cerebral artery (MCA) blood flow velocity (MV) were monitored. RESULTS: At rest, MV in the MCA did not differ significantly between controls and hypertensive subjects. MV continuously increased in controls until the end of loading whereas a plateau was reached at 4 min in hypertensive subjects. During 6 min of cycling, the time course of absolute values of MV in the MCA and that of the changes in the ratio of mean velocity/end-tidal CO2 (DeltaMV/DeltaetCO2) differed significantly between hypertensive subjects and controls (p = 0.03 and p = 0.02, respectively). CONCLUSION: Ergometer cycling combined with TCD revealed altered vasoreactivity, therefore this may be a sensitive method for the detection of early hemodynamic impairment in nontreated hypertensive subjects.

Adult↗

PubMed2001

Natural coagulation inhibitor proteins in young patients with cerebral ischemia.

Disturbances of coagulation and fibrinolytic pathways were studied in 53 young patients with cerebral ischemia. Upon admission 26 of 53 patients had abnormality in at least one of the antithrombin-III, protein C, protein S activities or in activated protein C (APC) ratios. Three months after the first examination the majority of the previously detected abnormalities returned to normal values and the most frequent alterations were decrease in protein S activity (3 patients) and APC resistance (3 patients). Conditions resulting in impaired fibrinolysis were frequently detected upon admission. Elevation of plasminogen activator inhibitor-1, lipoprotein (a), and alpha-2-antiplasmin was present in 23, 10, and 4 cases, respectively. It is concluded that abnormalities of coagulation as well as of the fibrinolytic systems are prevalent in the acute phase of cerebral ischemia, however, the results may be significantly influenced by the disease process or the acute phase effect.

Acute Disease↗

PubMed2001

A population study of stroke in West Ukraine: incidence, stroke services, and 30-day case fatality.

BACKGROUND AND PURPOSE: According to World Health Organization statistics, Ukraine has extremely high stroke mortality. No population-based prospective studies of stroke incidence have been performed yet in this European country with approximately 50 million inhabitants. High reported rates of stroke mortality in official statistics conflict with some locally published incidence data in Ukraine. To obtain accurate data, we evaluated stroke incidence and 30-day case fatality in a prospective population study in the West Ukrainian city of Uzhgorod with a population of 126 000 inhabitants. METHODS: Case certification by neurologists and follow-up at 30 days after stroke for all patients identified by any level of the health service system were performed for a 12-month period. RESULTS: We identified 352 stroke cases. The age-standardized incidence was 341 and 238 of 100 000 and mortality was 83 and 69 of 100 000 with the use of the European or world standard population for standardization. Mean age of stroke patients was 63.4+/-12.5 years. Rate of hospitalization was 66%. Hospitalized patients were >10 years younger than those treated in their homes. The 30-day case fatality rates were 15.4% among hospitalized patients and 36.8% among those treated at home. Overall 30-day case fatality was 23.3%. CONCLUSIONS: Stroke incidence and 30-day case fatality in this West Ukrainian city were similar to those of some West European countries and were much lower than what could be expected from World Health Organization statistics. The relatively low incidence rate seems accurate; because of the organization of local stroke services, it is not probable that a considerable proportion of patients with acute stroke could bypass all levels of the acute care health system. Local health statistics reported a much lower number of stroke cases and stroke deaths than found in our survey; thus, further study is needed to clarify the reason for the discrepancy between local data and the high reported stroke mortality in Ukraine.

Acute Disease↗

PubMed2001

18F-FDG PET mapping of regional brain activity in runners.

BACKGROUND: To examine regional metabolic changes in the human brain induced by free running in upright posture. METHODS. EXPERIMENTAL DESIGN: Regional brain changes in glucose uptake induced by running were examined by comparing brain images obtained by positron emission tomography (PET) and 18F-fluorodeoxyglucose (FDG). SETTING: The study was conducted at a research institute and involved participation of healthy young volunteers. Data sampling and analysis required special imaging device and special computer hardware/software. PARTICIPANTS: Subjects were 17 healthy male volunteers. They were divided at random into two equal groups, those who ran 4-5 km and the others sat in the room. MEASURES: differences in regional cerebral glucose uptake between runners and control groups were assessed statistically. Plasma glucose level was also measured and global cerebral uptake was estimated. RESULTS: Running was associated with a relative increase of glucose uptake in the temporoparietal association cortex, occipital cortex, premotor cortex and the cerebellar vermis. The highest activity was noted in the temporoparietal association cortex. Activity of the primary sensorimotor cortex was higher in the superomedial part (leg motor area) than the lateral part (thorax and arm). CONCLUSIONS: Running augmented energy consumption in the parieto-occipital region relative to the motor area, probably due to the higher energy consumption necessary for integration of multimodal sensory information than for generation of motor output. Our results indicate that FDG PET is a useful tool for brain mapping under various physiological conditions.

Adult↗

PubMed2000

Vinpocetine for acute ischaemic stroke.

BACKGROUND: Vasoactive and neuroprotective drugs are used to treat stroke in some countries. OBJECTIVES: The objective of this review was to assess the effect of vinpocetine in acute ischaemic stroke. SEARCH STRATEGY: We searched the Cochrane Stroke Group trials register (last searched: August 1999) and Medline. We contacted researchers in the field and drug companies. SELECTION CRITERIA: Unconfounded randomised trials of vinpocetine compared with placebo, or any other reference treatment, in people with acute stroke. Trials were included if treatment started no later than 14 days after stroke onset. DATA COLLECTION AND ANALYSIS: Two reviewers independently applied the inclusion criteria. One reviewer extracted the data that was then checked by the second reviewer. Trial quality was assessed. MAIN RESULTS: One trial involving 40 patients was included. Data for 33 patients were reported. No deaths occurred in the trial and no significant difference in dependency was shown between the treatment and placebo groups. No adverse effects were reported. REVIEWER'S CONCLUSIONS: There is not enough evidence to evaluate the effect of vinpocetine on survival or dependency of patients with acute stroke.

Brain Ischemia↗

PubMed2000

A Hungarian example for handsearching specialized national healthcare journals of small countries for controlled trials. Is it worth the trouble?

The objective of this study was to determine whether a Hungarian language journal of clinical neuroscience, which is not indexed in MEDLINE, contains any reports of randomized or quasi-randomized clinical trials that are not also reported in MEDLINE-indexed publications. A cover-to-cover handsearch was performed of the journal Clinical Neuroscience/Ideggyógyászati Szemle, the official journal of Hungarian societies of neurology, neurosurgery, psychiatry and related clinical neurosciences, from its first volume in 1950 to the end of 1998; and a search of MEDLINE for other reports of the trials identified. Clinical trials in which patients were allocated to interventions by randomized, quasi-randomized or possibly randomized means were identified. Controlled trials were tabulated and coded as randomized controlled trials or controlled clinical trials according to the definitions of the Handsearch Manual of the Cochrane Collaboration. We identified three randomized and eight quasi-randomized trials. Six of the 11 trials were not reported in MEDLINE indexed publications. In conclusion, to obtain a comprehensive controlled trials register, specialized healthcare journals printed in small numbers in the national languages of small countries should be searched.

Bibliometrics↗

PubMed2000

Gender-related differences in acetazolamide-induced cerebral vasodilatory response: a transcranial Doppler study.

Cerebrovascular reactivity, cerebrovascular reserve capacity, and velocity acceleration can be easily and reliably assessed by measuring acetazolamide-induced changes using transcranial Doppler. The authors' aim was to determine whether there are gender-related differences in these parameters. Fifty-six healthy subjects (27 males, 29 females) were examined using transcranial Doppler. Velocities in the middle cerebral artery on both sides were recorded before and at 5, 10, 15, and 20 minutes after intravenous administration of 1 g acetazolamide. The baseline mean flow velocity in the middle cerebral artery was significantly higher in women than in men (p < 0.02). After acetazolamide administration, significantly higher cerebrovascular reactivity, cerebrovascular reserve capacity, and velocity acceleration were observed in females than in males (p < 0.001 in all cases). Subgroup analysis showed that women before menopause responded with higher cerebrovascular reserve capacity and velocity acceleration than age-matched men (p < 0.01 and p < 0.001, respectively), but no significant difference was found between females after menopause and men of similar age.

Acetazolamide↗

PubMed2000

Cochrane report: A systematic review of mannitol therapy for acute ischemic stroke and cerebral parenchymal hemorrhage.

BACKGROUND: Mannitol was reported to decrease cerebral edema associated with tissue damage and is used to treat acute stroke in many countries. SUMMARY OF REVIEW: We tested whether there is any evidence from unconfounded randomized clinical trials that treatment with mannitol reduces short- and long-term case fatality and dependency if administered after ischemic stroke or cerebral parenchymal hemorrhage. Trials were identified by the standard search strategy of the Cochrane Collaboration Stroke Review Group. A supplementary MEDLINE search was performed, and the Chinese Stroke Trials Register and the Latin-American databank LILACS were checked. A search was performed of master's and PhD degree theses in the databank of Sao Paulo University and in abstracts of medical congresses on neurology and neurosurgery during 1965-1997 in Brazil. Investigators were contacted for unpublished information. Only truly randomized unconfounded clinical trials were eligible for inclusion. Two of the reviewers independently extracted data from the trials. Data synthesis and analysis was performed with the use of the Cochrane Review Manager software (RevMan version 4.0.4). CONCLUSIONS: Only 1 trial fulfilled the inclusion criteria. The number of included patients was small, and the follow-up was short. Case fatality, the proportion of dependent patients, and side effects were not reported and were not available from the investigators. As a result of lack of appropriate randomized trials, currently no conclusion can be drawn on the effects of mannitol in acute stroke. The routine use of mannitol in all patients with acute stroke is not supported by evidence from randomized controlled clinical trials.

Acute Disease↗

PubMed1999

[Carotid atherosclerotic lesions in stroke patients with diabetes mellitus].

The aim of the study was to assess the incidence of atherosclerotic lesions on carotid arteries among diabetic subjects suffering from cerebrovascular accident. A further aim was to investigate the relationship between the severity of the carotid lesion, the stroke subtype and the fatal outcome. One hundred and sixty eight patients treated because of cerebrovascular accident at the Dept. of Neurology University Medical School of Debrecen were studied. The age of the patients, the duration of diabetes and hypertension were registrated. Base on duplex scanning carotid lesions were divided in 6 groups of severity (normal, intimal sclerosis, slight, moderately severe, severe stenosis and occlusion). Based on clinical signs and CT results stroke subtypes were divided into five groups (lacunar and non-lacunar infarctions, hemorrhages, normal CT and others). The relationship between severity of carotid lesions, stroke subtype and lethal outcome was assessed using statistical tests. Carotid stenosis of different severity was detected in 60% of the cases. Severity of stenosis was independent from duration of diabetes, but it was positively related to duration of hypertension (p = 0.016). In 1/3 of the patients lacunar strokes, in another 1/3 non-lacunar strokes were observed. No significant relationship was found between severity of carotid stenosis, stroke subtype and lethal outcome of the patients (p = 0.53 and p = 0.26 respectively). Diabetic patients suffering from stroke have a higher incidence of carotid artery atherosclerotic lesions than diabetics without stroke. A special attention should be paid to the carotid duplex sonography in order to detect diabetic cerebral macroangiopathies in early, asymptomatic stage.

Aged↗

PubMed1999

[Evidence-based medicine. (Role of the Cochrane collaboration)].

The basic condition of practising evidence-based medicine is the knowledge of the evidence. Strongest of all evidences are the conclusions drawn from systematic reviews of randomized controlled trials. The over 2 million papers published annually in the biomedical literature is neither available nor possible to read for any individual, therefore it is necessary to identify and collect all relevant clinical trials, to make them available in databases, and to produce, to publish and to update systematic reviews based on the best evidence. The Cochrane Collaboration was established for these purposes in 1993. The activity of the Collaboration is summarized by a database The Cochrane Library which is updated quarterly. The user friendly Cochrane Library currently contains bibliographic data of over 218 thousand controlled trials (Cochrane Controlled Trials Register, CC-TR), and 1014 systematic reviews (Cochrane Database of Systematic reviews, CDSR) prepared by reviewers in 49 Review Groups. As the Cochrane Library contains information on much more controlled trials than any other databases including MEDLINE, decision makers in health care should be aware of this source of information. In addition to the application of the Cochrane Library as a source of information, active participation by identifying controlled trials in the Hungarian medical literature and registering them in the CCTR is another important task.

Clinical Medicine↗

PubMed1999

A systematic review of vinpocetine therapy in acute ischaemic stroke.

OBJECTIVES: To determine whether vinpocetine decreases short- and long-term case fatality and proportion of dependent survivors if administered within 2 weeks of stroke onset. METHODS: All published and unpublished trials were attempted to be identified using the standard search strategy of the Cochrane Collaboration Stroke Review Group, using MEDLINE searches performed with all known manufacturer code names and trade names of vinpocetine and by contacting manufacturers of vinpocetine to give information of all randomised controlled trials on vinpocetine in stroke. Researchers who participated in trials on vinpocetine in Hungary were asked for further information. Only truly randomised, unconfounded clinical trials that compared the effect of vinpocetine to either placebo or another reference treatment for acute stroke where treatment started no later than 14 days after stroke onset were eligible for inclusion. Data synthesis and analysis was performed using the Cochrane Review Manager software (RevMan version 3.0). RESULTS: Among the identified studies on vinpocetine in stroke, only one fulfilled the selection criteria for inclusion in the review. No death occurred in the study groups and no statistically significant difference was found in dependency between the treatment and the placebo groups. No adverse effects were reported. CONCLUSIONS: Based on only one small randomised controlled unconfounded study, presently there is not enough evidence to decide whether the administration of vinpocetine does or does not decrease case fatality and dependency in acute stroke.

Cerebrovascular Disorders↗

PubMed1999

No relationship between cerebral blood flow velocity and cerebrovascular reserve capacity and contemporaneously measured glucose and insulin concentrations in diabetes mellitus.

Blood glucose and insulin concentrations have been reported to influence cerebral hemodynamics. We studied the relationship between actual blood glucose and insulin concentrations and resting cerebral blood flow velocity in the middle cerebral artery and cerebrovascular reserve capacity after acetazolamide stimulation. Thirty-six insulin-dependent diabetic patients in a state of good glycemic control were studied. Blood samples were taken for determination of glucose and insulin concentrations. Subsequently we measured resting cerebral blood flow velocities in supine position using transcranial Doppler, administered 1 g acetazolamide intravenously, and repeated the measurements after 5, 10, 15 and 20 minutes. Cerebrovascular reserve was calculated as the maximal percent increase after acetazolamide stimulation. Multiple regression was used for statistical analysis. Blood glucose levels were not correlated with resting blood flow velocity (R = 0.21, p = 0.22) nor cerebrovascular reserve capacity (R = 0.17, p = 0.32). Similarly, no correlation was found between insulin concentrations, resting cerebral blood flow velocity (R = 0.24, p = 0.22) and cerebrovascular reserve (R = 0.26, p = 0.24). Studying patients with long-term (> 10 years) and short-term (</= 10 years) disease duration yielded the same lack of correlation. We conclude that there is no significant correlation between contemporaneously measured glucose and insulin concentrations and either cerebral blood flow velocity or cerebrovascular reserve capacity in the middle cerebral artery in type 1 diabetic patients with good control.

Acetazolamide↗

PubMed1999

Basic characteristics of hospital stroke services in Eastern Hungary.

Stroke mortality is extremely high in Central-Eastern European countries. We report basic characteristics of a stroke unit in Eastern Hungary, including age and sex distribution; the proportion of transient ischemic attacks (TIA), ischemic and hemorrhagic strokes; case fatality; application of diagnostic methods; and length of stay for all patients treated with acute cerebrovascular disease over a 12-month period. Records of all patients with acute cerebrovascular disease (n = 522) discharged in 1995 from a stroke unit with a well defined catchment area of 220,000 inhabitants in Eastern Hungary were retrospectively analyzed. Case fatality was 18.6% for all patients and 21.1% after excluding cases with TIA. Computer tomography, duplex carotid ultrasound, cerebrospinal fluid examination and electroencephalography were performed in 79%, 77%, 7% and 2% of the patients, respectively. The database of the university hospital with the same catchment area was electronically searched for patients who were discharged with the diagnosis of stroke from the three departments of internal medicine. Stroke mortality data of the catchment area based on death certificates was obtained from the Central Statistical Bureau. Two hundred twenty-eight stroke deaths were reported in the catchment area in 1995. In the same period 97 stroke deaths occurred at the stroke unit and 76 at the departments of internal medicine. If we aim to treat all patients with acute stroke at the stroke unit, with the present stroke incidence and duration of hospital stay the current capacity of the stroke unit (1 bed per 10.000 inhabitants) should be doubled.

Adult↗