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Helmuth Steinmetz

Publications and source records attributed to Helmuth Steinmetz.

26 records · Page 2Linked to original sources
PubMed2002

Brain size and grey matter volume in the healthy human brain.

Magnetic resonance imaging was used to evaluate the influence of sex and brain size on compartmental brain volumes (grey matter, white matter, CSF) in a large and well-matched sample of neurologically normal women (n = 50) and men (n = 50). As expected, we found a significant sex difference for the absolute volumes of total brain, grey matter, white matter and CSF, with greater volumes for men. Relating these compartmental volume measures to brain volume resulting in proportional volume measures revealed a higher proportion of grey matter in women. No significant sex differences were found for white matter and CSF proportions. However, when the influence of sex was partialized out by regression analyses, brain volume explained 40-81% of the variance of the absolute grey matter, white matter and CSF volumes. Performing these regression analyses for the proportional volume measures revealed that brain volume explained approximately 16% of the variance in grey matter proportion. Sex or the interaction between sex and brain volume revealed no additional predicitve values. Interestingly, the correlation between brain volume and grey matter proportion was negative, with larger brains exhibiting relatively smaller proportions of grey matter. Thus, sex is not the main variable explaining the variability in grey matter volume. Rather, we suggest that brain size is the main variable determining the proportion of grey matter.

Adult↗
PubMed2002

The temporal lobe in schizophrenia from uni- and multiply affected families.

To investigate the effect of genetic loading on brain structure in schizophrenia, we hypothesized that separating families into uniaffected and multiply affected would reveal effects of schizophrenia and family type. Volumes and asymmetries of the amygdala-hippocampus-complex (AHC) and sylvian fissure (SF) were determined using magnetic resonance imaging of subjects with schizophrenia from 12 uniaffected and 14 multiply affected families, and ten healthy controls. AHC volume was reduced in schizophrenia, particularly on the right side in subjects from uniaffected families. AHC asymmetry was disturbed, too. Enlargement of the right SF and disturbed SF asymmetry was demonstrated in subjects from uniaffected families as well. Comparing subjects from uni- and multiply affected families may be a useful strategy to reduce variability for future studies of environmental interactions with genetic risk for schizophrenia.

Adult↗
PubMed2002

Helicobacter pylori infection, the cytotoxin gene A strain, and carotid artery intima-media thickness.

BACKGROUND: Chronic Helicobacter pylori infection has been implicated as a risk factor for stroke and other cardiovascular disease. It has been suggested that it acts by promoting atherogenesis. A particular strain of H. pylori, the cytotoxin gene A strain (CagA strain), which has been associated with increased inflammation, has been reported to account for much of this relationship. An early estimate of atherosclerosis can be obtained by ultrasonic imaging of the carotid artery to determine intima-media thickness (IMT). We determined whether H. pylori infection, and particularly the CagA strain, is associated with increased IMT. METHODS: In 983 normal population individuals we measured common carotid artery (CCA) IMT. From serum samples we determined H. pylori and CagA status. RESULTS: There was no significant association between H. pylori seropositivity and CCA IMT after controlling for age and gender. There were significant relationships between H. pylori seropositivity and a number of conventional cardiovascular risk factors (age, systolic and diastolic blood pressure, body mass index, smoking) and after controlling for these the magnitude of the regression coefficient was reduced by a further half. Amongst H. pylori seropositives the CagA strain was associated with increased IMT after controlling for age and gender (B = 0.0256, 95% CI 0.001-0.050, P = 0.038). The relationship was no longer significant after controlling for other cardiovascular risk factors. (B = 0.0194, 95% CI -0.004-0.042, P = 0.098). CONCLUSIONS: H. pylori and the CagA strain are not major risk factors for early arteriosclerosis as assessed by carotid artery intima-media thickness.

Adult↗
PubMed2002

C-reactive protein and carotid intimal medial thickness in a community population.

BACKGROUND: C-reactive protein (CRP) has been linked to cardiovascular disease and atherosclerosis. Large-scale epidemiological studies have shown a correlation of CRP level with risk of stroke, myocardial infarction and peripheral arterial disease. Nevertheless, the question whether serum CRP itself is an independent indicator of the atherosclerotic process remains unanswered. METHODS: In a community-based sample free of advanced atherosclerotic disease (n = 1018; mean age +/- SD, 54.1 +/- 12.0 years; 49.7% women) we examined the relationship between carotid intimal medial thickness (IMT), conventional vascular risk factors (that is, smoking, obesity, elevated blood pressure, diabetes mellitus, hypercholesterolaemia) and serum CRP. RESULTS: We found an association between increasing IMT values with increasing CRP values for all sites within the carotid system (for example, common carotid artery [CCA-] IMT, beta = 0.174, P < 0.001). The relationship was weakened after accounting for the above-mentioned conventional risk factors (linear regression), particularly body mass index, but remained significant (for example, mean CCA-IMT beta = 0.02, P = 0.042). Including fibrinogen in the regression made the relationship no longer significant (mean CCA-IMT beta = 0.01, P = 0.277). CONCLUSION: It is unlikely that CRP per se is a major independent cause of early arteriosclerosis. Elevations of CRP, or less specifically chronic inflammation, may mediate the effect of certain conventional risk factors on promoting atherogenesis, especially obesity.

Adult↗
PubMed2002

Recanalization results after carotid stent placement.

BACKGROUND AND PURPOSE: The details of stent reconstruction in the vascular lumen and of the adaptation of carotid stents, the vessel wall, and the vascular anatomy are only occasionally reported. The purpose of this study was to determine the immediate and longer-term anatomic results after implantation of self-expanding carotid stents. METHODS: In a retrospective study, pre- and postprocedural angiograms and duplex sonograms from 40 consecutive carotid stent procedures in 39 patients (22 men, 17 women; mean age, 67 years; age range, 53-84 years) with high-grade (> or =70 %) internal carotid artery (ICA) stenoses were evaluated to assess the expansion of the vascular lumen, apposition of the stent, and geometric changes in the ICA after the implantation of rolling-membrane and carotid Wallstents (n = 22) or Easy Wallstents (n = 18). RESULTS: Optimal widening of the lumen and apposition of the stent were achieved in 11 (28%) of 40 arteries. Residual stenoses (n = 16), free stent filaments not attached to the vessel wall (n = 21), and stent-induced kinking of the ICA (n = 6) were minor shortcomings of stent reconstruction. Because of one death, peri-interventional morbidity and mortality rates were 3%. During follow-up (median, 24 months), one high-grade restenosis, one ipsilateral stroke, and two ipsilateral transient ischemic attacks were observed. CONCLUSION: Suboptimal anatomic results frequently occur after endovascular treatment of atherosclerotic carotid artery stenosis with self-expanding Wallstents. With the exception of one symptomatic restenosis, no major complications or longer-term sequelae were clearly related to these findings, but further controlled follow-up studies of larger samples are required.

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PubMed1996

Microembolism in Carotid Artery Disease.

Abnormal high intensity transient signals detectable with transcranial Doppler (TCD) sonography have been associated with formed cerebral microembolism. Using long-term TCD monitoring, these clinically silent microembolic events can be observed in patients with cerebrovascular disease. Downstream of high grade internal carotid artery (ICA) stenosis, they occur significantly more frequently in neurologically symptomatic than in asymptomatic patients. Although the occurrence of microemboli is random, the individual rate underlies circadian fluctuations and seems to decline within the first weeks after an ischemic event. Pathoanatomic work suggests that luminal ulcer and thrombosis of the stenosed ICA are the major sources of microemboli. Thus, by tapping into an important pathomechanism, the detection of clinically silent cerebral microembolism appears to provide paraclinical evidence of "unstable carotid artery disease" and may help to evaluate more specific treatment strategies. (ECHOCARDIOGRAPHY, Volume 13, September 1996)

Journal Article↗
PubMedDate not supplied

Difference in recognition of right and left hemispheric stroke.

Symptoms of cerebrovascular events differ depending on the hemisphere in which the lesion arises, thereby affecting disease recognition and management. We aimed to establish whether left and right hemispheric strokes are unequally distributed in inpatients. We obtained data from a large hospital-based stroke registry in Germany. 11,328 patients (56%) had left hemispheric events and 8769 (44%) had right-sided lesions (p<0.0001). Age, stroke severity, and time from symptom onset to admission were significantly associated with left hemispheric stroke, suggesting a selection effect. Difficulties in recognition of symptoms due to right hemispheric stroke challenge efforts to optimise stroke management, particularly in the critical early hours of stroke.

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