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N Zöllner

Publications and source records attributed to N Zöllner.

At least 19 recordsLinked to original sources

[Gout].

In most cases gout is the clinical manifestation of familial hyperuricemia. Pathogenesis of hyperuricemia, clinical manifestations, diagnosis and differential diagnosis of hyperuricemia and gout are described. Treatment of hyperuricemia consists of dietary measurements and administration of uric acid lowering drugs, such as allopurinol or uricosuric agents. Nonsteroidal antiinflammatory drugs, colchicine and glucocorticosteroids are the treatment of choice for the acute gout attack. Prophylaxis of acute uric acid nephropathy consists of hydration, urine alkalinization and administration of allopurinol or rasburicase. For treatment of acute uric acid nephropathy rasburicase is the drug of choice.

Allopurinol↗

Influence of dietary linoleic acid intake with different fat intakes on arachidonic acid concentrations in plasma and platelet lipids and eicosanoid biosynthesis in female volunteers.

BACKGROUND/AIM: N-6 fatty acids are considered to promote diseases prevalent in industrialized countries and characterized by an increased eicosanoid biosynthesis from arachidonic acid (AA). We investigated the impact of the linoleic acid (LA) intake on AA levels in humans. METHODS: Six healthy female volunteers (age range 23-34 years) were given liquid formula diets (LFD) devoid of AA for 6 weeks, providing a constant intake of zero energy% (LFD 0: protein 15%, carbohydrates 85%) or 20 energy% (LFD 20: protein 15%, carbohydrates 55%, fat 30%) LA, for 3 weeks each. Fatty acids of plasma cholesteryl esters and platelet lipids were determined each week, and the prostaglandin biosynthesis was measured in 24-hour urine samples. RESULTS: LFD 0 increased (+31% of initial value) and LFD 20 lowered (-30% of initial value) the percentage of AA in plasma cholesteryl esters and platelet lipids. Moreover, absence of dietary AA lowered the percentages of AA in plasma (-31% week 0 vs. week 6) and platelet (-11%) lipids, indicating a low transformation of LA. LFD 0 reduced urinary metabolite levels of prostaglandins D, E, and F in 24-hour urine samples (-48%, p < 0.001) within 24 h, but did not significantly affect platelet aggregation (-10%) and thromboxane formation (-25%). LFD 20 significantly lowered platelet aggregation (-25%) and thromboxane formation (-43%). The prostaglandin metabolite levels increased during the first 10 days, declined thereafter, and were lower than the preexperimental values at the end of the 3-week period. CONCLUSIONS: The results show that dietary LA does not increase the AA levels in plasma or platelet lipids and does not persistently contribute to prostaglandin biosynthesis which is increased by AA intake with Western diets.

Adult↗

Lipid clinics.

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Ambulatory Care Facilities↗

Familial hypercholesterolemia and familial defective apolipoprotein B-100: comparison of the phenotypic expression In 116 cases.

Familial hypercholesterolemia (FH) is characterized by an increased level of LDL cholesterol, tendon xanthomas and an elevated risk of premature coronary artery disease (CAD). FH is caused by different mutations in the low density lipoprotein receptor (LDLR) gene or by a G to A mutation in exon 26 of the apolipoprotein B gene causing familial defective apolipoprotein B-100 (FDB). To compare the phenotypic expression of either defect, we studied 83 patients (76 heterozygous and 7 homozygous persons) with LDLR defects and 33 heterozygous FDB patients from Germany. We took into account other risk factors for CAD. In contrast to earlier studies, our patients where prospectively ascertained from the lipid clinic and tested for the G-A mutation. The average total cholesterol level in plasma was 413.7 mg/dl in LDLR patients and 321.8 mg/dl in FDB patients. Patients with LDLR defects had a significantly higher risk of myocardial infarction, coronary artery bypass graft, positive coronary angiography, atherosclerotic plaques in the carotid arteries and CAD (p<0.01) than patients with FDB. CAD was present in 33% and plaques in the carotid arteries in 82% of the patients with LDLR defects. No patient with FDB had severe CAD, while only 52% had plaques in the carotid arteries (p<0.05). Thus in our study, hypercholesterolemia and premature atherosclerosis were more common in LDLR patients than in FDB patients. We believe that the striking difference in CHD incidence is not sufficiently explained by the higher LDL levels in LDLR patients. A possible explanation may be that in LDLR patients, the metabolism of low density lipoproteins, intermediate density lipoproteins and very low density lipoproteins is disrupted, whereas in FDB patients there is only disruption in apo B-containing LDL.

Angioplasty↗

[Hyperuricemia].

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Adult↗

Identification of the valine 408 to methionine mutation in the LDL receptor in a Greek patient with homozygous familial hypercholesterolemia.

We have identified the cytosine to thymine change in the codon for amino acid 408 which causes valine to be replaced by methionine in exon 9 of the LDL receptor gene in a 12-year-old Greek boy living in Germany, with homozygous familial hypercholesterolemia, by using polymerase chain reaction-amplified genomic DNA and subsequent restriction digestion. Homozygosity was confirmed by direct DNA sequencing. The mutation was present in both his parents, and his brother, grandmother, uncle and cousin. Six restriction fragment length polymorphisms of the LDL receptor gene were used to determine the haplotype of the defective allele. The haplotype was different from the one reported earlier in African Afrikaners and from Holland. We conclude that the mutation in the Greek boy probably occurred as an independent mutation. Because the parents are from different areas in Greece, this mutation may be common in Greeks.

Base Sequence↗

Ten LDL receptor mutants explain one third of familial hypercholesterolemia in a German sample.

Mutational defects in the LDL receptor are responsible for familial hypercholesterolemia (FH); thus far more than 150 mutations have been described. Nevertheless, systematic searches among the Germans have not been conducted. We used single-strand conformational polymorphism and polymerase chain reaction to find mutations in 10 index patients and in 40 other individuals with heterozygous FH. Our screen in the 10 index patients revealed 7 hitherto undescribed mutations. A screen of the 40 additional FH patients disclosed 20 defective of 54 total alleles and allowed specific diagnoses in 88 family members. We also found two families in which the children were markedly affected by FH, but the expected parental expression of the trait was not manifest. This observation suggests a role for additional environmental and genetic influences. Our report represents the first comprehensive effort to identify FH mutations in Germany. We found 10 mutations and these mutations explain 37% of FH cases. Our data may have relevance to expected FH patterns in central Europe.

Adult↗

[Hyperuricemia].

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Adult↗

Anecdotal evidence.

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Anecdotes as Topic↗

Influence of selective management on the prognosis and the risk of rupture of abdominal aortic aneurysms.

A total of 199 patients with abdominal aortic aneurysms were followed up to investigate the influence of selective management on the prognosis and the risk rupture of abdominal aortic aneurysms. Decisions to operate or to continue watchful waiting with treatment of risk factors for expansion were based on aneurysm size, expansion rate, aneurysm-related symptoms, and individual operative risk. Rupture occurred in eight cases. All aneurysms were larger than 5 cm, and six were larger than 6 cm in diameter at the last measurement before rupture. The resulting overall 5-year cumulative rate of rupture was 7.3% (Kaplan Meier). The 134 patients who underwent more than one ultrasound examination were observed for an average of 4.0 years (536 patient-years). The expansion rate was significantly correlated with the initial diameter and the diastolic blood pressure (best subset multiple regression analysis: r = 0.403; P < 0.001). A correlation with the systolic blood pressure was found only in univariate analysis (r = 0.236; P = 0.011). Amplitude of blood pressure, serum cholesterol level, low-density and high-density lipoproteins, ratio of low- to high-density lipoproteins age, and the extent of smoking habits were not correlated with the expansion rate. Our conclusion is that larger diameter and higher diastolic blood pressure are important risk factors for expansion of abdominal aortic aneurysms. Selective management of abdominal aortic aneurysms based on aneurysmal size, expansion rate, and patient characteristics may result in a low rate of rupture.

Adult↗

Interaction of allopurinol and hydrochlorothiazide during prolonged oral administration of both drugs in normal subjects. I. Uric acid kinetics.

The interaction of allopurinol (300 mg/day) and hydrochlorothiazide (50 mg/day) was studied in seven healthy male volunteers during prolonged coadministration of the two drugs using defined dietary conditions. A formula diet was administered with the allopurinol throughout the 24-day study, while hydrochlorothiazide was added during days 11-21. After the addition of hydrochlorothiazide both plasma uric acid and plasma oxipurinol rose for 6 days--24% and 30%, respectively, compared to steady-state levels during allopurinol alone (P < 0.01 each). In neither substance were variations in renal excretion significant. By the end of combined treatment (day 21), the changes induced by hydrochlorothiazide had already been reversed to a considerable extent. It is concluded that both in normal individuals and in patients with normal renal clearance of uric acid the effect of hydrochlorothiazide on the plasma concentration and renal excretion of oxipurinol is small. When taking both drugs, there is no increased risk during long-term treatment, and a risk is even questionable during the first days.

Administration, Oral↗

Interaction of allopurinol and hydrochlorothiazide during prolonged oral administration of both drugs in normal subjects. II. Kinetics of allopurinol, oxipurinol, and hydrochlorothiazide.

The kinetics of allopurinol and hydrochlorothiazide were investigated in seven healthy male subjects during prolonged coadministration of two drugs. Subjects were maintained on an isoenergetic, purine-free formula diet with RNA supplementation for 24 days. Allopurinol (300 mg) was given orally on days 1-24. Hydrochlorothiazide (50 mg daily) was added to days 11-21. On day 43 a single oral dose of 50 mg hydrochlorothiazide was administered. Plasma concentration-time profiles of allopurinol and its main metabolite oxipurinol were obtained on days 1, 10, and 21; hydrochlorothiazide profiles were assessed on days 21 and 43. In addition, 24-h plasma concentrations of oxipurinol were measured repetitively, and 24 h urine samples were collected for the determination of allopurinol, oxipurinol, and hydrochlorothiazide. For oxipurinol, mean Cmax was not altered on hydrochlorothiazide treatment (13.8 +/- 1.4 micrograms/ml and 14.7 +/- 2.6 micrograms/ml, respectively); mean AUC0-24 was 259 and 290 micrograms h-1 ml-1, respectively. The small difference in AUC0-24 values does not explain the increase in plasma uric acid concentration during hydrochlorothiazide treatment, nor do the variations in allopurinol and hydrochlorothiazide kinetics.

Administration, Oral↗

Identification of defective binding of low density lipoprotein by the U937 proliferation assay in German patients with familial defective apolipoprotein B-100.

Familial defective apolipoprotein B-100 (FDB) is a dominantly inherited disorder characterized by decreased binding of low density lipoprotein (LDL) to the LDL receptor due to a substitution of glutamine for arginine in residue 3500 of apolipoprotein B-100. We present the results of the U937 cell proliferation assay for the detection of familial defective apo B100 in 13 German FDB patients. Due to a defect in the pathway of cholesterol synthesis the human myelomonocytic tumour cell line U937 lacks the ability to synthesize cholesterol which makes proliferation of these cells dependent on the presence of exogenous LDL-cholesterol. U937 cells were incubated with LDL from 13 FDB-patients, 10 healthy normocholesterolaemic individuals (NC) and 26 patients with familial hypercholesterolaemia due to a defective LDL-receptor (FH). At LDL-cholesterol concentrations below 1 microgram ml-1 no proliferation occurred. In the presence of LDL from FDB patients at concentrations between 2.5 micrograms ml-1 and 15.0 micrograms ml-1, the proliferation was significantly reduced compared to LDL from FH-patients and normocholesterolaemic controls. At 5 micrograms ml-1 the reduction was 31-80% regardless of age, sex, apo E genotype, Lp(a)- and lipid levels. At concentrations above 25.0 micrograms ml-1 no further differences were observed. The present results indicate that the U937 proliferation assay is a reliable test for the detection of defective LDL-binding due to the 3500 mutation in FDB patients. It may be useful for the detection of defective binding of LDL due to other mutations in the apo B-100 gene.

Adult↗