PubMed Health⌕ Search

Biomedical subjects

W Strobl

Publications and source records attributed to W Strobl.

At least 37 records · Page 2Linked to original sources
PubMed1996

Austrian report on longitudinal outcome in phenylketonuria.

Forty years after Horst Bickel first treated a patient suffering from phenylketonuria (PKU) our aim is to assess the current treatment of Austrian patients. A total of 70 children -60 with PKU and 10 with hyperphenylalaninaemia (HPA)-aged 6-16 years were investigated in terms of somatic and intellectual parameters. Their development is normal (PKU: mean IQ = 95.40; HPA: mean IQ = 101.85) owing to strict dietary control, above all during their first 6 years of life. A comparison of the IQ data of 17 PKU children and their healthy siblings at the age 6 years showed significant correlations in verbal, performance and IQ measurements. Austrian PKU patients do achieve normal IQ values but these measurements fail to guarantee the quality of dietary control. IQ is influenced by a number of variables: genetic, social environment, education and furtherance, motivation for performance, etc., and, in PKU patients, dietary control. The only currently known way of maintaining and improving dietary compliance in PKU patients and their families remains good informative counselling about the disease and psychosocial support.

Adolescent↗
PubMed1995

Thyroid hormone influences conditional transcript elongation of the apolipoprotein A-I gene in rat liver.

Chronic administration of thyroid hormone (T3) increases apoA-I gene expression in rat liver by enhancing mRNA maturation, but reduces apoA-I mRNA synthesis to 50% of control. To gain insight into the inverse relation of mRNA maturation and mRNA synthesis, we measured transcription in livers of control and T3-treated rats (50 micrograms/100 g body weight for 7 days) by nuclear run-on assays using overlapping antisense RNA probes encompassing the apoA-I gene. In control rats, after normalization for hybridization efficiency and probe length, the hybridization signals with intron 3 probes were reduced to 45% of those obtained with exon 1 to exon 3 probes (P < 0.01) indicating transcriptional arrest or pausing close to the exon 3-intron 3 border or 450 to 650 nucleotides downstream of the transcription start site. In T3-treated rats, the elongation block was nearly twice as effective, while the rate of transcription initiation was similar to control. In contrast, the distribution of nascent transcripts across the apoA-IV gene was symmetric, and T3-treatment suppressed apoA-IV mRNA synthesis by processes operating in the 5' region such as transcription initiation. Thus, conditional transcript elongation contributes to the regulation of apoA-I gene expression in rat liver.

Animals↗
PubMed1995

[Direct detection of Toxoplasma gondii with polymerase chain reaction in diagnosis of fetal toxoplasma infection].

Primary infection with Toxoplasma gondii during pregnancy may affect the fetus and result in congenital toxoplasmosis. In Austria serological screening for detection of newly acquired infection during pregnancy was introduced in 1975. In this study we used polymerase chain reaction (PCR) for detection of fetal infection with Toxoplasma gondii. Amniotic fluid samples were analyzed from 11 women with serological indication of acute toxoplasmosis infection. Nine of these women had already received treatment prior to amnio-centesis and no evidence of Toxoplasma gondii DNA was detected with PCR in the respective amniotic fluid samples. Isolation of the organism by mouse inoculation was negative in these cases and follow-up serology as well as clinical examination of the infants confirmed these results. In 2 patients investigation of the amniotic fluid samples by means of PCR was positive; both women had not yet been treated at the time of amniocentesis. Our results indicate that identification of Toxoplasma gondii in amniotic fluid is a useful procedure for diagnosing or excluding fetal infection. Moreover, the current recommendations of the screening program appear to be successful in preventing congenital toxoplasmosis.

Amniotic Fluid↗
PubMed1993

Altered regulation of apolipoprotein A-IV gene expression in the liver of the genetically obese Zucker rat.

Apolipoprotein (apo) A-IV, a structural component of chylomicrons and high-density lipoproteins, may play a role in the catabolism of triglyceride-rich lipoproteins and in reverse cholesterol transport. To study the regulation of apoA-IV gene expression by genetic and nutritional factors, we determined the effect of a fish oil-rich and a sucrose-rich diet on apoA-IV gene transcription and nuclear and total cellular apoA-IV mRNA abundance in livers of genetically obese, hyperlipoproteinemic (fa/fa) Zucker rats and their lean (Fa/-) littermates. In obese rats fed chow, hepatic apoA-IV gene expression was more than twofold higher than in lean rats because of a post-transcriptional mechanism. apoA-I gene expression and apoC-III mRNA levels, studied as controls, were similar in both groups. The fish oil-rich diet reduced total cellular apoA-IV mRNA abundance transcriptionally to 34 +/- 4% of basal values in lean rats, but did not alter apoA-IV gene expression in obese rats. In contrast, this diet reduced apoA-I gene expression in both lean and obese animals. The sucrose-rich diet increased apoA-IV gene expression twofold in both lean and obese rats. Thus, genetic obesity alters the response of hepatic apoA-IV gene expression to a lipid-lowering diet rich in fish oil by a mechanism affecting transcriptional regulation.

Animals↗
PubMed1993

Role of thyroid hormone in the expression of apolipoprotein A-IV and C-III genes in rat liver.

The genes coding for apolipoproteins A-I, C-III, and A-IV are closely linked to one another in the rat genome. Thyroid hormone stimulates apoA-I expression in rat liver by an unusual mechanism that enhances the maturation of mRNA. This hormone also increases apoA-IV mRNA abundance by a mechanism not yet studied, and its role in the expression of apoC-III has not been defined but may be of relevance to the metabolism of triglyceride-rich lipoproteins. We therefore measured the transcriptional activity of the apoA-IV and apoC-III genes and the abundance of their nuclear RNA and total cellular mRNA in livers of control rats and rats made hyper- and hypothyroid. After a single receptor-saturating dose of triiodothyronine (3 mg/100 g body weight), apoA-IV gene transcription increased at 20 min and reached a maximum of 260% of control at 6 h. Increases of transcription were reflected in increases of nuclear and total apoA-IV mRNA levels. ApoC-III gene transcription was temporarily increased to 160% at 2 h without changes in the abundance of its nuclear or total mRNA over 24 h. Lower hormone doses (20-500 micrograms/100 g body weight) stimulated apoA-IV mRNA transcription as well, but tended to reduce transcription from the apoC-III gene. Upon chronic administration of thyroid hormone, apoA-IV transcription decreased to 55% and nuclear apoA-IV RNA levels to 87% of control. However, total cellular apoA-IV mRNA levels increased to 279% of control, implying stabilization of mRNA in the cytoplasm. ApoC-III transcription decreased to 28% of control, but abundance of nuclear and total cellular apoC-III mRNA was reduced to a lesser extent. In hypothyroid rats, apoA-IV gene expression was decreased fourfold at the transcriptional level. In contrast, apoC-III gene transcription increased to 178% of control, but the abundance of nuclear and total cellular apoC-III mRNA did not differ from control rats. Thus, thyroid hormone affects the abundance of apoA-IV mRNA by changing its synthesis and its rate of degradation and enhances the efficiency of apoC-III mRNA maturation, thereby blunting the net effect of altered mRNA synthesis on mRNA abundance.

Animals↗
PubMed1992

Effect of sucrose diet on expression of apolipoprotein genes A-I, C-III and A-IV in rat liver.

A sucrose-rich diet stimulates hepatic lipogenesis and induces net production of very low density lipoproteins in the liver. To study changes of hepatic apolipoprotein gene expression in response to such a diet, we measured the mRNA abundance of apolipoproteins A-I, C-III and A-IV in livers of rats fed a sucrose-rich diet or a control diet for 3 weeks. In livers of sucrose-fed rats, the abundance of cellular and nuclear apo A-IV mRNA increased to 185% +/- 21% and 142% +/- 22% of control values (P less than 0.01), respectively. In sucrose-fed rats, the transcriptional activity of the apo A-IV gene, measured in a cell-free transcription system using isolated liver nuclei, increased to 144% +/- 23% of control (P less than 0.05). In contrast, this diet neither affected the abundance of cellular and nuclear apo A-I and apo C-III mRNA nor the transcriptional activity of these genes in liver. These results are consistent with specialization of the regulatory elements of the genes coding for apolipoproteins A-I, C-III and A-IV. Alternatively, enhanced transcription of the apo A-IV gene may preclude increased synthesis of apo A-I and/or apo C-III mRNA due to the close linkage of the three genes in the rat genome.

Animals↗
PubMed1992

Differential regulation of hepatic apolipoprotein A-I and A-II gene expression by thyroid hormone in rat liver.

Apolipoproteins A-I and A-II (apo A-I, apo A-II) are major protein components of high density lipoproteins. Thyroid hormone has a differential effect on the expression of the apo A-I and apo A-II genes in rat liver. Apo A-I gene expression is stimulated by thyroid hormone, whereas apo A-II mRNA abundance is decreased in chronic hyperthyroidism. To determine the regulatory steps involved in this differential effect of thyroid hormone on hepatic apo A-I and apo A-II gene expression, we studied the effect of short term and chronic hyperthyroidism on apo A-I and apo A-II gene transcription rates, nuclear RNA abundance and total cellular mRNA levels. After a single receptor saturating dose of L-triiodothyronine (T3) apo A-II gene transcription was transiently increased to 164% +/- 13% of basal values (P < 0.05) without affecting nuclear apo A-II RNA abundance. Apo A-I gene transcription, however, increased to 158% +/- 8% of baseline levels (P < 0.05) and remained elevated for at least 24 h. Nuclear and total cellular apo A-I mRNA increased more than expected from the increased transcription rate suggesting nuclear RNA stabilization and/or more efficient processing of the primary transcripts. In chronic hyperthyroidism, total cellular apo A-II mRNA abundance decreased to 62% +/- 18% (P < 0.05) and apo A-II gene transcription and apo A-II nuclear RNA were moderately reduced. By contrast, apo A-I nuclear and total cellular RNA were increased several fold by post-transcriptional mechanisms, whereas apo A-I gene transcription was drastically decreased. We conclude that the apo A-I and apo A-II genes in rat liver respond differently to both acute and chronic hyperthyroidism and that their expression is regulated at transcriptional and posttranscriptional levels.

Animals↗
PubMed1992

[A comparative study of the sensory conduction velocity of the sural nerve using surface and needle electrodes].

In 18 healthy persons aged 22-71 years and 17 patients suffering from clinically defined polyneuropathy the NCV of the sural nerve was measured both by antidromic technic recorded by surface electrodes and by orthodromic technique recorded by needle electrodes. Stimulation was done by bipolar surface electrodes in all cases. The skin temperature was warmed up to the minimum of 35 degrees C. The results showed in both groups a highly significant correlation of the NCV measured by antidromic and orthodromic technique. With increasing age the NCV decreased, but this was not significant. In all healthy persons sensory nerve potentials could be recorded with both techniques. In polyneuropathy missing of sensory potentials was higher in patients investigated by the antidromic technique than by orthodromic. For clinical practice measurement of NCV in sural nerve using antidromic technique should be preferred because of its simpler and faster achieving, its lower discomfort for the patient and avoiding risk of infection. However in case of missing nerve potentials, orthodromic investigation using needle electrodes for recording should be added.

Adult↗
PubMed1991

Determination of serum apolipoprotein B by competitive enzyme-linked immunoassay.

An enzyme-linked immunoassay was used to determine apolipoprotein B (apoB) in serum samples from 104 healthy adults aged 18-26 years. The method was compared to radial immunodiffusion (RID). Mean apoB values were 103 +/- 30 mg/dl and 105 +/- 31 mg/dl respectively. The correlation coefficient for apoB between the two methods was r = 0.70, p less than 0.001; the correlation coefficient between LDL-cholesterol and apoB measured by the ELISA was r = 0.73, p less than 0.001. This ELISA technique seems to be an appropriate method for measuring apoB in plasma, in the clinical laboratory and for detecting individuals with hyperapobetalipoproteinaemia.

Adolescent↗
PubMed1990

Role of thyroid hormones in apolipoprotein A-I gene expression in rat liver.

To study the regulation of hepatic apo A-I gene expression, we measured synthesis and abundance of cellular apo A-I mRNA and its nuclear precursors in livers of hypothyroid and hyperthyroid rats. In hypothyroid animals, both synthesis and abundance of apo A-I mRNA was reduced to half of control values. After injection of a receptor-saturating dose of triiodothyronine into euthyroid rats, apo A-I gene transcription increased at 20 min, reached a maximum of 179% of control (P less than 0.01) at 3.5 h, and remained elevated for up to 48 h. The abundance of nuclear and total cellular apo A-I mRNA increased at 1 and 2 h, respectively, and exceeded the levels expected from enhanced transcription more than two fold at 24 h after hormone injection. Upon chronic administration of thyroid hormones, levels of nuclear and cytoplasmic apo A-I mRNA remained elevated but transcription of the apo A-I gene fell to 42% of control (P less than 0.01). Thus, thyroid hormones rapidly stimulate apo A-I gene transcription. Posttranscriptional events leading to increased stability of nuclear apo A-I RNA precursors become the principal mechanism for enhanced gene expression in chronic hyperthyroidism and may cause feedback inhibition of apo A-I gene transcription. Our results furthermore imply that the majority of hepatic nuclear apo A-I RNA precursors are degraded in euthyroid animals.

Albumins↗
PubMed1989

Effect of sucrose diet on apolipoprotein biosynthesis in rat liver. Increase in apolipoprotein E gene transcription.

A sucrose-rich diet stimulates the biosynthesis of very low density lipoproteins in rat liver. This diet also increases the triglyceride content of hepatic very low density lipoproteins and changes their apolipoprotein composition. To study the changes of hepatic apolipoprotein biogenesis in response to such a diet, we measured secretory rates of apolipoproteins A-I, B, and E in cultured rat hepatocytes. In cultures from rats fed the sucrose-rich diet the production of apolipoprotein E was increased 2-fold as compared to controls, whereas the production of apolipoproteins A-I and B was unchanged. The enhanced production of apolipoprotein E could be accounted for by a 2-fold increase in hepatic apolipoprotein E mRNA, as measured by slot blot hybridization. To characterize the mechanisms leading to the increase of liver apolipoprotein E mRNA levels we measured the transcriptional activity of the apolipoprotein E gene in a cell-free transcription system using isolated liver cell nuclei. Transcriptional activity of the apolipoprotein E gene was 7% that of albumin gene transcription in control animals. In rats fed a sucrose-rich diet the transcription rate of the apolipoprotein E gene increased to 140 +/- 11% of controls. There was no change in albumin gene transcription. Thus, a sucrose-rich diet enhances apolipoprotein E biosynthesis in rat liver, at least in part, by stimulating transcription of the apolipoprotein E gene.

Animals↗
PubMed1988

Apolipoprotein A-I (Glu 198----Lys): a mutant of the major apolipoprotein of high-density lipoproteins occurring in a family with dyslipoproteinemia.

To detect genetic mutants of apo A-I, the major structural protein of human HDL, we screened 530 unrelated Austrian probands (168 children, 362 adults). An apo A-I mutant characterized by an exchange of the acidic amino acid Glu in position 198 with the basic amino acid Lys was identified in the serum of the mother of a hyperlipoproteinemic girl. So far only two patients with this mutant, referred to as apo A-I (Glu 198----Lys) have been described. We detected six new patients (two children and four adults) with apo A-I (Glu 198----Lys) among 20 members in three generations of the affected family. An autosomal codominant inheritance of the apolipoprotein variant could be established. All affected individuals were heterozygous for the mutant. Among the six new subjects with apo A-I (Glu 198----Lys) two children and one adult presented with high-density lipoprotein (HDL) cholesterol concentrations below the fifth percentile for age and sex and with low serum apo A-I and A-II. Although there was no consistent relationship of the mutant with low serum HDL in this family, a moderate effect of apo A-I (Glu 198----Lys) on HDL levels cannot be ruled out. Hyperlipoproteinemia of types IIa, IIb, and IV was observed in eight of the 20 family members studied, but did not cosegregate with the mutant apo A-I. There was no association of apo A-I (Glu 198----Lys) with premature clinical manifestations of atherosclerosis. The mutation occurred in a part of the apo A-I molecule, which is thought to be involved in lipid binding.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1987

Increase of serum lipids and serum lipoproteins in girls under therapy with estrogen and norethisteron for height reduction.

The effect of a combined treatment with ethinyl estradiol and norethisteron for height reduction on serum lipids and lipoproteins was investigated in 23 excessively tall girls (greater than 97th percentile). Serum cholesterol, triglycerides, HDL-C and LDL-C were determined before and 3, 6, 9 and 12 months after the onset and 3 to 12 months after cessation of therapy. Treatment with ethinyl estradiol and norethisteron resulted in significant (p less than 0.01) mean increases in serum cholesterol, triglycerides, HDL-C, and LDL-C of 20.6%, 95.5%, 23.6%, and 22.2% above pretreatment values, respectively. This increase occurred during the first 3 months of therapy and thereafter no further significant change was observed. After cessation of therapy elevated levels returned to pretreatment levels within 3 to 12 months in all but two patients. The results obtained suggest an influence of ethinyl estradiol and norethisteron on serum lipids and lipoproteins. Whether these reversible changes of serum lipids and lipoproteins are associated with an increased risk for developing atherosclerosis has to be evaluated in long term investigations.

Adolescent↗
PubMed1985

Apolipoproteins and lipoproteins in children with type I diabetes: relation to glycosylated serum protein and HbA1.

Serum levels of cholesterol (C), triglycerides (TG), lipoprotein-C and apolipoproteins (apo) A-I, A-II and B were measured in 30 children with type I diabetes mellitus (16 boys, 14 girls, aged 11-14 years) and in 26 healthy controls (15 boys, 11 girls, aged 10-13 years). For 19 diabetics controls matched for age, sex and relative body weight were selected. The diabetic patients were considered to be in fair metabolic control according to HbA1 levels and glycosylated serum protein concentrations. Mean serum apo A-I, A-II and B, C, TG, low density lipoprotein cholesterol (LDL-C) and high density lipoprotein cholesterol (HDL-C) did not differ significantly between diabetic nondiabetic children. Very low density lipoprotein cholesterol (VLDL-C) was significantly higher in diabetic children than in controls. Serum C and LDL-C levels showed close univariate linear correlations with glycosylated serum protein (LDL-C: r = 0.53, p less than 0.01, C: r = 0.58, p less than 0.01) in diabetics. The ratio LDL/HDL-C was significantly correlated to HbA1 levels (r = 0.47, p less than 0.01). By canonical and multiple linear correlation analysis significant relations of a selected set of variables concerning the control and therapy of diabetes (serum glucose, HbA1, glycosylated serum protein, insulin dose) with a set of lipoprotein variables (C, TG, VLDL-C, HDL-C, LDL-C, apo A-I, A-II, B) could be demonstrated. From these data we conclude that significant relations between atherogenic serum lipids and lipoproteins (C, LDL-C) and the degree of metabolic control exist in diabetic children, even in the absence of marked dyslipoproteinemia.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1984

[Diagnosis and effective therapy with plasmapheresis in a patient with homozygous familial hypercholesterolemia].

The case of a 17-year-old boy with the homozygous form of familial hypercholesterolaemia is reported. The patient presented tuberous and tendinous xanthomas, arcus lipoides, complete occlusion of the LAD of the coronary arteries, a characteristic family history, and total cholesterol levels greater than 600 mg/dl. Among the available therapeutic regimens we decided to perform plasma exchange treatment, which was introduced by Thompson in 1973 as therapy of this metabolic disorder. After each plasmapheresis, performed so far 7 times, the cholesterol and LDL-cholesterol concentrations dropped to normal levels; they increased again within the next 3 weeks, without, however, reaching the pretreatment levels. Undergoing this treatment, the xanthomas decreased markedly; there are reasons to assume that atherosclerotic lesions might also decrease during this treatment.

Adolescent↗