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H Schulte

Publications and source records attributed to H Schulte.

At least 73 records · Page 4Linked to original sources

A missense mutation (Thr-6Pro) in the lysosomal acid lipase (LAL) gene is present with a high frequency in three different ethnic populations: impact on serum lipoprotein concentrations.

A frequent missense mutation (Thr-6Pro) found in the prepeptide of the lysosomal acid lipase (LAL) gene was analyzed in a cohort of 1003 randomly selected samples from Germany, Japan and Sardinia (Italy). Using the mutagenically separated polymerase chain reaction (MS-PCR), allele frequencies of 0.269, 0.238 and 0.245 were determined in the three populations, respectively. Statistical analysis showed a lack of association with a dyslipidemic phenotype in all three groups. Additionally, in a subgroup of 126 German individuals no association was observed between genotype and LAL activity. We conclude that this mutation appears to be a frequent LAL gene polymorphism causing no impaired function of the enzyme and no measurable dyslipidemia in the general population.

Base Sequence↗

High-density lipoprotein cholesterol as a predictor of coronary heart disease risk. The PROCAM experience and pathophysiological implications for reverse cholesterol transport.

The incidence of coronary heart disease (CHD) was assessed via the Prospective Cardiovascular Münster (PROCAM) study in 19,698 volunteer subjects aged between 16 and 65 years. An adequate incidence of atherosclerotic CHD was only found in male subjects greater than 40 years of age. The analysis and subsequent 6 year follow-up period was, therefore, confined to 4559 male participants aged 40-64 years. In the follow-up period, 186 study participants developed atherosclerotic CHD (134 definite non-fatal myocardial infarctions (MIs) and 52 definite atherosclerotic CHD deaths including 21 sudden cardiac deaths and 31 fatal MIs). Univariate analysis revealed a significant association between the incidence of atherosclerotic CHD and high-density lipoprotein cholesterol (P < 0.001), which remained after adjustment for other risk factors.

Adolescent↗

Synthesis and release of phosphatidylcholine by isolated porcine gastric mucous cells in primary culture.

Phosphatidylcholine (PC) is the major phospholipid of the hydrophobic gastric mucosal barrier and is chiefly released from mucous cells into the gastric mucus. Whereas the mucosa contains highly unsaturated PC, gastric mucus predominantly contains palmitoyl-oleoyl-PC and palmitoyl-linoleoyl-PC, indicating a selective release of these PC species into the gastric lumen. In order to understand gastric PC metabolism, we investigated synthesis and release of PC in cultivated porcine gastric mucous cells, using dual labelling with [methyl-3H]-choline and [1-14C]-palmitate, in the presence of 12-O-tetradecanoylphorbol-13-acetate (TPA), indomethacin and prostaglandin E2 (PGE2). Linear incorporation of [methyl-3H]-choline and [1-14C]-palmitate into PC was achieved for at least 8h. In contrast to type II pneumocytes TPA increased PC synthesis in gastric mucous cells but not its release. Indomethacin did not influence PC synthesis, but it decreased the release of newly synthesized PC. PGE2 antagonized the effect of indomethacin on PC release. We conclude that PC release by isolated porcine gastric mucous cells is regulated in a manner different from type II pneumocytes. PC release is impaired by indomethacin and this impairment is restored by PGE2.

Animals↗

Ethinylestradiol 20 versus 30 micrograms combined with 150 micrograms desogestrel: a large comparative study of the effects of two low-dose oral contraceptives on the hemostatic system.

In a 6-month, randomized, double-blind study the effects of two combined oral contraceptives containing 150 micrograms desogestrel and either 20 or 30 micrograms ethinylestradiol on hemostatic parameters were investigated in 1633 healthy women. Compared with baseline, the 30 micrograms ethinylestradiol formulation increased prothrombin fragment 1 + 2 (+72.2%), D-dimer (+42.4%) and protein C activity (+6.1%), whereas antithrombin-III activity (-6.3%) and protein S activity (-19.7%) were decreased. The use of the 20 micrograms ethinylestradiol formulation was associated with the same pattern of changes, but with lower magnitude (F1+2 + 61.1%, D-dimer +36.0%, antithrombin III -5.3%, protein C +4.6% and protein S-16.0%). The changes from baseline were significantly smaller in the 20 micrograms ethinylestradiol group for D-dimer, antithrombin III and protein S than in the 30 micrograms ethinylestradiol group (p = 0.019, p = 0.038 and p = 0.001, respectively). One woman with a combined deficiency of proteins C and S developed deep venous thrombosis while using the 20 micrograms ethinylestradiol formulation. Use of both formulations was associated with a shift of the coagulation-fibrinolysis balance to an enhanced fibrin-generating and fibrin-degradating activity. The less-pronounced effect on hemostasis with the 20 micrograms ethinylestradiol preparation is reassuring with regard to thromboembolic risk in general. However, women with coagulation inhibitor deficiency should be advised not to use oral contraceptives.

Adolescent↗

Elevated low-density lipoprotein-cholesterol in women with polycystic ovary syndrome.

Previous studies have indicated that women with the polycystic ovary syndrome (PCOS) are affected by hypertriglyceridemia and low high-density lipoprotein-cholesterol (HDL-C) level. However, most of these studies did not control for confounding factors such as body mass index (BMI) or differences in ethnicity. Therefore, we compared the lipid data for 26 women with PCOS with those for 1428 female control participants of the Prospective Cardiovascular Münster (PRO-CAM) study who did not use hormonal contraceptives and were of similar age. Data were adjusted for age, BMI and ethnicity. Women with PCOS had higher total cholesterol (5.55 +/- 1.24 vs. 4.99 +/- 0.88 mmol/l, p < 0.05) and low-density lipoprotein-cholesterol (LDL-C) levels (3.61 +/- 1.19 vs. 3.08 +/- 0.82 mmol/l, p < 0.05) than the control subjects. Compared with the women in the control population, those with PCOS more frequently had triglyceride levels exceeding 2.3 mmol/l (11.5 vs. 1.6%, p < 0.001), LDL-C levels exceeding 4.2 mmol/l (30.8 vs. 12.1, p < 0.01), and HDL-C levels below 1.2 mmol/l (46.2 vs. 15.3%, p < 0.001). We conclude that dyslipidemia is found more frequently in women with PCOS, independently of the excess weight that is often found in this patient group.

Adult↗

Hemostatic variables in the prediction of coronary risk: results of the 8 year follow-up of healthy men in the Münster Heart Study (PROCAM). Prospective Cardiovascular Münster Study.

Myocardial infarction is usually due to the acute formation of an occlusive thrombus within the coronary arteries, in most cases against a background of pre-existing coronary atherosclerosis. Both of these factors may be promoted by a procoagulant state of the hemostatic system. Plasma fibrinogen, factor VIIc, blood pressure, and lipid parameters were measured in 2,781 healthy men aged 40-65 in the Münster Heart Study (formerly known as the PROCAM Study). After 8 years of follow-up 130 coronary events (15 sudden cardiac deaths, 22 fatal myocardial infarctions, and 93 nonfatal myocardial infarctions) were observed. Plasma fibrinogen concentration and factor VIIc activity were significantly greater among men who suffered a coronary event. The mean plasma fibrinogen level of the event group exceeded that of the non-event group by 0.32 g/l [2.59 +/- 0.58 vs. 2.91 +/- 0.58 (mean +/- SD) respectively, P < 0.001]. The incidence of coronary events among men within the upper tertile of fibrinogen concentration was three times higher than among men within the lower tertile. Plasma factor VIIc activity was 112.4 +/- 20.1% in the event group and 108.7 +/- 21.4% in the non-event group (P < 0.05). Among men in the upper tertile of factor VIIc activity, the incidence of coronary events was 1.6 times that of men in the lower tertile. When fibrinogen and low density lipoprotein (LDL) concentration were considered together, there was a graded and dramatic eightfold increase in 8 year risk from 17 per 1,000 of population among men with both fibrinogen and LDL cholesterol in the lower tertiles to 130 per 1,000 in men with both of these parameters in the upper tertile. In men with LDL cholesterol in the lowest tertile, increasing fibrinogen levels did not increase the risk of a coronary event. The coagulation variables, fibrinogen concentration, and factor VIIc activity thus markedly improve our ability to predict coronary risk.

Adult↗

Impact of polymorphisms in the alpha- and beta-fibrinogen gene on plasma fibrinogen concentrations of coronary heart disease patients.

Despite many investigations in a variety of experimental settings, uncertainty remains concerning the size of the genetic contribution to plasma fibrinogen levels. We used the polymerase chain reaction to amplify the polymorphic sites for the restriction enzymes TaqI in the alpha-fibrinogen gene and HaeIII, HindIII and BclI in the beta-fibrinogen gene. Three hundred and eighty-four male coronary heart disease patients were investigated. Two alleles for each enzyme (+ or - designating, respectively, the presence or absence of the cutting site) were detected. The HaeIII and HindIII cutting sites were in complete linkage disequilibrium. A small but significant increase in fibrinogen level was associated with the rare cutting sites of HaeIII/HindIII, BclI and TaqI. At all polymorphic sites homozygosity for the frequent alleles was associated with about 0.20 g/l lower plasma fibrinogen concentrations than heterozygosity at the respective sites (p < 0.05). The frequencies and natures of the rare alleles were as follows: TaqI (+) 0.28, HaeIII/HindIII (-) 0.22 and BclI (+) 0.17. Mean fibrinogen levels in patients heterozygous for each of the four polymorphisms were 0.47 g/l greater than in subjects homozygous for the frequent allele at each cutting site (HaeIII/HindIII + -, TaqI + -, BclI + -: fibrinogen level 3.58 g/l (n = 32); HaeIII/HindIII + +, TaqI - -, BclI - -: fibrinogen level 3.11 g/l (n = 99), p = 0.003). Each polymorphism accounted for between 0.5 and 1.4% of the overall variance in fibrinogen concentration. Together, the polymorphisms in HaeIII, HindIII and TaqI explained 5.8% of overall variance, a proportion equivalent to that explained by age, smoking and body mass index (5.5%).(ABSTRACT TRUNCATED AT 250 WORDS)

Alleles↗

Molecular analysis at the Harvey Ras-1 gene in patients with long QT syndrome.

Patients with long QT syndrome (LQTS; MIM 1921500) frequently suffer from syncope and are threatened by sudden cardiac death due to ventricular arrhythmias, typically of the torsade de pointes type. Initial progress in revealing the molecular basis of the disease was made by the observation of genetic linkage of the disease locus to the Harvey Ras-1 gene (HRAS 1) on chromosome 11p15.5. More recently loci on chromosomes 3, 4, and 7 have also been found to be linked to LQTS, thus demonstrating heterogeneity in the causes for this disease. The present study performed sequence analysis on the HRAS 1 gene in patients with congenital and acquired LQTS to determine the frequency of HRAS 1 mutations in patients with this disease. In neither group were no mutations identified in the coding regions or in the splice donor and acceptor sites. Alleles characterized by a T to C transition in exon 1 and an insertion/deletion polymorphism upstream of exon 1 showed no significant difference in their frequencies between LQTS patients and normal controls. No quantitative influence of the such characterized genotypes on the QT duration was observed. These results demonstrate that structural mutations in the HRAS 1 gene are not a frequent cause of LQTS. Also, since there was no association of different alleles at the HRAS 1 locus with changes in QT duration, it appears unlikely that this gene is a major contributor to this disease.

Alleles↗

Screening for naturally occurring apolipoprotein A-I variants: apo A-I(delta K107) is associated with low HDL-cholesterol levels in men but not in women.

Isoelectric focussing (IEF) in carrier ampholyte-generated pH gradients and hybrid isoelectric focussing (HIEF) in immobilized pH gradients under nondenaturing conditions were used in parallel to screen 5,500 plasma samples for naturally occurring variants of apolipoprotein A-I (apo A-I). The following defects were identified in four unrelated subjects heterozygous for apo A-I variants: apo A-I(delta K107)(2 x), apo A-I(K107M)(1 x), and apo A-I(E41R)(1 x). The later variant is a novel finding. Family studies did not reveal any association of apo A-I(K107M) and apo A-I(E41R) with dyslipidemia, but identified several heterozygotes for apo A-I(delta K107) who had low levels of high density lipoprotein (HDL)-cholesterol. Therefore, and since the apo A-I(delta K107) is the most frequent apo A-I variant in Germany (1: 5,000) we evaluated our data and that reported from 11 families with 32 heterozygous carriers and 30 unaffected controls. This analysis revealed that apo A-I(delta K107) is associated with lower HDL-cholesterol (-30%) and higher triglycerides (+48%) in men but not in women as compared with unaffected family members as well as with controls from the Prospective Cardiovascular Münster (PROCAM) study. Moreover, 11 of 15 male apo A-I(delta K107) heterozygotes but only 2 of 17 female apo A-I(delta K107) heterozygotes had HDL-cholesterol levels below the 20th percentile of sex-matched controls from the PROCAM study. We conclude that heterozygosity for apo A-I(delta K107) decreases HDL-cholesterol and increases triglycerides in men but not in women.

Apolipoprotein A-I↗

Effect of hypertriglyceridaemia on lipoprotein (a) serum concentrations.

Numerous studies have shown lipoprotein (a) [Lp(a)] serum levels above 0.3 gL-1 to be a genetically determined and independent risk factor for atherosclerotic vascular disease. In this study of sera from 1009 patients attending our lipid clinics, multivariate regression analysis revealed an inverse correlation between the serum concentrations of triglycerides (TG) and Lp(a) (r = -0.31; P < 0.001) as determined by electroimmunodiffusion. This was not observed in 1237 controls from a random population. Detailed analysis of the frequency distribution of Lp(a) levels at different degrees of hypertriglyceridaemia (HTG) revealed a decreasing dosage effect of HTG on Lp(a) serum levels. In 60% of patients with TG > 9.12 mmol L-1, this effect led to undetectable serum Lp(a) levels. Dilution of hypertriglyceridaemic samples with normotriglyceridaemic sera containing high levels of Lp(a) revealed that analytical interference in part accounts for the decreasing effect of TG-rich lipoproteins on Lp(a). Re-evaluation of 45 hypertriglyceridaemic samples by enzyme immunoassay and immunoblotting revealed the presence of small amounts of Lp(a) in several samples which were considered to be free of Lp(a) upon electroimmunodiffusion. We conclude that TG-rich lipoproteins interfere with the quantification of Lp(a), at least by electroimmunodiffusion. However, HTG may also decrease Lp(a) plasma concentrations in vivo, possibly by increased clearance of TG-rich Lp(a).

Adult↗

Association of variables of coagulation, fibrinolysis and acute-phase with atherosclerosis in coronary and peripheral arteries and those arteries supplying the brain.

We investigated the vessel status of coronary and peripheral arteries and those arteries supplying the brain in 929 consecutive male patients admitted to a coronary rehabilitation unit. The severity of coronary atherosclerosis was scored using coronary angiography. Changes in extracranial brain vessels and manifest cerebrovascular disease (CVD) were determined by B-mode ultrasound and Doppler examination. Peripheral arterial disease (PAD) was diagnosed using base-line and stress oscillography. We assessed variables of coagulation, fibrinolysis, and the acute phase response. There was a significant increase in plasma fibrinogen, plasminogen, d-dimer and C-reactive protein (CRP) with increasing severity of coronary heart disease. Compared to men with unaffected arteries, men with 3 diseased coronary arteries had 58% greater d-dimer concentrations. Patients with CVD and PAD, respectively, also had significantly higher fibrinogen, d-dimer and CRP concentrations. We did not find an association between plasminogen activator inhibitor activity and the severity of coronary atherosclerosis. In conclusion, plasma fibrinogen, d-dimer and CRP concentrations were significantly related to atherosclerosis in the coronary, peripheral and extracranial brain arteries.

Acute-Phase Reaction↗

Comparison of risk factors for coronary heart disease in Dresden and Münster. Results of the DRECAN (Dresden Cardiovascular Risk and Nutrition) study and the PROCAM (Prospective Cardiovascular Münster) Study.

Trend analyses based on WHO statistics for average life expectancy, age-standardized cardiovascular (CVD) morbidity and mortality show significant differences between the former German Democratic Republic (GDR) and the former Federal Republic of Germany (FRG). To investigate whether this is due to a different prevalence of cardiovascular risk factors, the Dresden Cardiovascular Risk and Nutrition (DRECAN) study was conducted using the complete methodology of the Prospective Cardiovascular Münster (PROCAM) study, i.e., the same methods and strict quality controls, with an exchange of specimens between both laboratories. The results were compared with those of an adjusted subpopulation of the PROCAM study. Even before unification there were only small differences in lipoprotein profiles between West and East Germany, 10 months after unification these differences were minimal. The survey does not sufficiently explain the differences in CHD morbidity and mortality between Western and Eastern Germany. Further analyses of the nutritional aspects will show whether the change, in available foodstuffs after unification has led to substantially changed nutritional habits, and whether this might explain some of the results.

Adolescent↗

Identification of individuals at high risk for myocardial infarction.

The incidence of atherosclerotic coronary heart disease (CHD) was assessed in 4559 male participants of the Prospective Cardiovascular Münster (PROCAM) study, aged 40-64 years, over a 6 year follow-up period. In this time, 186 study participants developed atherosclerotic CHD (134 definite nonfatal myocardial infarctions and 52 definite atherosclerotic CAD deaths including 21 sudden cardiac deaths and 31 fatal myocardial infarctions). In multiple logistic function (MLF) analyses, age, cholesterol, HDL cholesterol, systolic blood pressure, and the binary (yes/no) criteria of cigarette smoking, angina pectoris, diabetes mellitus or hyperglycaemia, and family history of myocardial infarction showed a significant association with the incidence of atherosclerotic CHD after adjustment for the other risk factors. In the subgroup of individuals, in whom clotting factors were measured, fibrinogen was found to be an independent additional risk indicator for CHD by multiple logistic function analysis (P < 0.05). The relationship between a variable and total mortality or some of its components was described by dividing the patient series into quintiles of the studied variable and then calculating the age-standardized death rate for each quintile. Lowest risk of total mortality occurs in men with lowest risk of CHD, though relationships between total mortality and levels of single risk factors are 'J'-shaped or even 'U'-shaped.

Adolescent↗

Raised lipoprotein(a) in hypercholesterolaemic black students compared to age-matched whites in North and South Carolina.

BACKGROUND: North and South Carolina are the states with the highest coronary death rates and also belong to the Stroke Belt of the US. From a Reflotron cholesterol screening in North and South Carolina schools, students with cholesterol levels > or = 4.66 mmol/l (> or = 180 mg/dl) were tested for high density lipoprotein (HDL), low density lipoprotein (LDL) and lipoprotein(a) (Lp(a)). METHODS: The 923 students aged 12-19 with mild hypercholesterolaemia represented one-third of the high school population, of whom 30% are black. Of the hypercholesterolaemic white students, 96% took the additional tests, of the hypercholesterolaemic black students, 88% responded. Lp(a) levels were determined by electroimmunodiffusion. RESULTS: Most important was a three-fold elevation of the geometric mean of Lp(a) values among blacks compared to whites: white males 9, white females 10, black males 25, black females 26 mg/dl, respectively, independent of age and sex. Relationships between Lp(a) and four other lipids/lipoproteins were examined and proved non-significant except for total cholesterol and LDL in black males and white females. While 70% of the white students displayed Lp(a) levels < 20 mg/dl, 65-70% of the black students showed Lp(a) levels > 20 mg/dl. CONCLUSIONS: Early identification of high Lp(a) levels may be of importance for two groups, (1) black females who have a 20% higher coronary heart disease mortality rate than white females in spite of significantly higher HDL levels; and (2) for black males and black females who have a prevalence of cerebrovascular disease twice as high as in whites.

Adolescent↗

Fibrinogen and factor VII in the prediction of coronary risk. Results from the PROCAM study in healthy men.

Coronary thrombosis is regarded as the final occlusive event in the progress of coronary heart disease (CHD). Disturbances of the hemostatic system may favor this process and thus may indicate increased risk of myocardial infarction. Coagulation and lipid factors were measured in 2116 healthy male participants of the Prospective Cardiovascular Münster (PROCAM) study. After 6 years of follow-up, 82 coronary events (9 sudden cardiac deaths and 14 fatal and 59 nonfatal myocardial infarctions) were observed. The mean plasma fibrinogen levels of the event and nonevent groups differed by 0.25 g/L (2.88 [SD, 0.68] versus 2.63 [SD, 0.63] g/L, respectively; P = .001). The incidence of coronary events in the upper tertile of the plasma fibrinogen distribution was 2.4-fold higher than in the lower tertile. By multiple logistic function analysis, plasma fibrinogen was found to be an independent risk indicator for CHD (P < .05). Individuals in the high serum low-density lipoprotein (LDL) cholesterol tertile who also showed high plasma fibrinogen concentrations had a 6.1-fold increase in coronary risk. Unexpectedly, individuals with low plasma fibrinogen had a low incidence of coronary events even when serum LDL cholesterol was high. The mean factor VIIc activities in the event and nonevent groups did not differ significantly (112.3% [SD, 19.9] versus 108.4% [SD, 21.6]; P = .09). There was, however, a trend toward higher factor VIIc values when only fatal events were taken into account. Thus, higher levels of plasma fibrinogen markedly increased the predictive power of high serum LDL cholesterol. Low plasma fibrinogen is associated with low coronary risk even when LDL is raised.

Adult↗

Plasma Lp(a) levels correlate with number, severity, and length-extension of coronary lesions in male patients undergoing coronary arteriography for clinically suspected coronary atherosclerosis.

The relation between lipoprotein(a) [Lp(a)] as an independent risk factor for coronary atherosclerosis and the severity and extension of angiographically detectable coronary atherosclerotic lesions has not been systematically evaluated. In 118 male patients (54.3 +/- 7.4 years) with suspected coronary artery disease and without a history of myocardial infarction undergoing coronary angiography, the relation between plasma Lp(a) levels and other lipoproteins and the severity and extension of coronary lesions was studied. The coronary angiograms were evaluated in a blinded manner according to three scores: vessel score (0 to 3 points for 0 to 3 vessels with stenoses > or = 70%), stenosis score (0 to 32 points; number and severity of coronary stenoses or lesions), and extent score (0 to 100 points; length-extension of all coronary lesions in relation to the total coronary vessel length). The score values obtained were analyzed for correlations with age and levels of total cholesterol (6.08 +/- 1.26 mmol/L; mean +/- SD), high-density lipoprotein cholesterol (1.04 +/- 0.33 mmol/L), low-density lipoprotein cholesterol (4.18 +/- 1.15 mmol/L), triglycerides (1.88 +/- 1.37 mmol/L), and Lp(a) in plasma (19.5 +/- 22.6 mg/dL). Bivariate correlation analysis resulted in positive correlations between Lp(a) and vessel score (P < .01), stenosis score (P < .01), and extent score (P < .05). With multivariate analyses, besides Lp(a) plasma level (nl), only patient age showed a significant correlation to all three scores used, whereas none of the lipid parameters correlated significantly with all three scores.

Adult↗

Effects of age, lipoproteins, and hemostatic parameters on the role of homocyst(e)inemia as a cardiovascular risk factor in men.

Previous studies have identified moderately elevated plasma concentrations of homocyst(e)ine as an independent risk factor for coronary heart disease (CHD). The atherogenicity of homocyst(e)ine has mostly been attributed to its effects on endothelial cells, platelets, and the hemostatic system. In this case-control study of 199 male CHD patients and 156 age-matched control subjects, we analyzed the role of homocyst(e)ine as a cardiovascular risk marker in the context of traditional risk factors as well as of plasma fibrinogen, plasminogen, and viscosity. Both univariate and multivariate regression analyses revealed that homocyst(e)ine levels were significantly correlated with age, fibrinogen, and plasma viscosity in both study groups. Geometric mean homocyst(e)ine levels by univariate analysis were significantly higher in patients than in control subjects (8.9 versus 7.8 mumol/L, P < .001). This difference remained significant on multiple logistic function analysis after being adjusted for body mass index, systolic blood pressure, serum cholesterol, and high-density lipoprotein cholesterol but not after additional adjustment for fibrinogen. By contrast, geometric mean fibrinogen levels after adjustment for homocyst(e)ine levels were significantly different between patients and control subjects (296.4 versus 230.8 mg/dL, P < .001). Within the group of CHD patients, both fibrinogen and homocyst(e)ine significantly increased in parallel with the number of stenosed coronary vessels. We conclude that hyperhomocyst(e)inemia is an independent coronary risk factor and that its interrelation with fibrinogen levels merits further study.

Adult↗