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C Luley

Publications and source records attributed to C Luley.

At least 55 records · Page 3Linked to original sources
PubMed1997

[Laparoscopic transperitoneal adrenalectomy--technique and personal experiences].

Laparoscopic transperitoneal and endoscopic extraperitoneal adrenalectomy are two safe options in minimally invasive surgery associated with very low morbidity. The anterior transperitoneal approach we prefer yields a better exposure of the anatomic structures and allows the surgeon to orient himself more easily. In addition, various other laparoscopic maneuvers may be performed synchronously. We report on our own experience with eight laparoscopic transperitoneal adrenalectomies performed in four cases unilaterally and in two additional cases bilaterally during April, 1996, and January, 1997, in six patients aged 20 to 56 years. The indications were in four cases pheochromocytoma (operated on bilaterally in two cases), and in the remaining two cases adrenal Cushing's syndrome. The duration of surgery was approximately 240 min for bilateral adrenalectomy and 166 min for unilateral adrenalectomy, respectively, with an intraoperative blood loss of about 50 to 400 ml. Except for haematoma of the abdominal wall there were no other postoperative complications. The serum levels of interleukin 6 and 10 underline the minimal invasiveness of this technique, since there were only small increases of interleukin 6 and interleukin 10.

Adrenal Gland Neoplasms↗
PubMed1996

Clearance of postprandial lipoproteins in normolipemics: role of the apolipoprotein E phenotype.

The hepatic clearance of triglyceride-rich lipoproteins is mediated via apolipoprotein (apo) E which occurs in three common isoforms, apoE2, apoE3 and apoE4. To study the importance of the apoE isoforms on the response curves of different triglyceride-rich lipoproteins and the effect of chylomicron remnants on the composition of HDL, 37 normolipemics were investigated after a standardized fatty meal (8 apoE2/E2, 8 apoE2/E3, 8 apoE3/E3, 7 apoE3/E4 and 6 apoE4/E4). These individuals were matched for age, body mass index, fasting triglycerides, HDL-cholesterol, and apoA-I. A delayed chylomicron remnant clearance was observed only in apoE2 homozygotes, and this delay was neither correlated with fasting lip ds nor with peak lipoprotein concentrations. In apoE2/E3 heterozygotes, in contrast, the defective isoform E2 appears to be compensated for by the normal apoE isoform E3. In non-apo-E2/E2 individuals, the chylomicron remnant response was highly correlated with the magnitude of chylomicron and VLDL responses, with fasting triglycerides, and with the triglycerides enrichment and cholesterol depletion of HDL. These correlations were not observed in apoE2/E2. From these results we conclude that the chylomicron remnant response curve is an indicator of the extent of postprandial lipemia in non-apoE2/E2 individuals only.

Adult↗
PubMed1996

[Snow white small intestinal villi in hypobetalipoproteinemia].

In contrast to the severe clinical picture of abetalipoproteinemia patients with hypobetalipoproteinemia are often asymptomatic. We demonstrate a 52-years-old female patient with a white mucosa of the small intestine casually observed by endoscopy. The white appearance of the mucosa was limited to the villi. As demonstrated by light and transmission electron microscopy this was caused by fat loaded enterocytes similar to the picture of abetalipoproteinemia. Fasting serum lipids and apolipoproteins were only if the lower norm level for some parameters, but no increase of the serum lipids was observed after an oral fat load. Because of the missing symptoms, the typical histomorphology and laboratory findings the snow white mucosa of the small intestine is due by the hetocygote form of the autosomal dominant hypobetalipoproteinemia with fat loaded enterocytes.

Apolipoproteins↗
PubMed1995

Effects of VLDL, chylomicrons, and chylomicron remnants on platelet aggregability.

Although influences of cholesterol-rich lipoproteins on platelet aggregation are well established, the knowledge of interactions between triglyceride-rich lipoproteins and platelets, in particular in the postprandial state, is limited and controversial. The in-vitro effects of these lipoproteins from hypertriglyceridemic subjects on the aggregation behavior of platelets from normolipemic donors were investigated with two whole-blood methods. VLDL and chylomicrons, but not chylomicron remnants, in concentrations comparable to concentrations occurring after a fatty meal, reduced platelet aggregation in a dose-dependent manner in particle counting. Impedance aggregometry failed to monitor these effects. We conclude, that triglyceride-rich lipoproteins inhibit platelet aggregation in vitro. They may, therefore, not be linked to the acute onset of myocardial infarction.

Adult↗
PubMed1995

Oxygraphic evaluation of mitochondrial function in digitonin-permeabilized mononuclear cells and cultured skin fibroblasts of patients with chronic progressive external ophthalmoplegia.

For quantitative elucidation of maximal mitochondrial oxidation capacities in human mononuclear cells, cultured human skin fibroblasts and human thrombocytes the optimal amount of digitonin for plasma membrane permeabilization was determined to be 5, 10, and 0.1 micrograms/10(6) cells, respectively. Using these concentrations the rate of respiration of permeabilized cells with the mitochondrial substrates succinate (+ rotenone) or glutamate + malate can be stimulated between two- and fourfold by ADP and inhibited by carboxyatractyloside. The maximal respiratory activities of well-characterized preparations of permeabilized mononuclear cells of five patients with chronic progressive external ophthalmoplegia were compared to healthy controls and a 30 to 50% decrease of the ADP-stimulated respiration rates with glutamate + malate and succinate + rotenone was detected. This is an indication for the presence of the mitochondrial defect in respiratory active blood cells. Additionally, for two of these patients the mitochondrial defects were proven to be detectable by the determination of maximal oxygen consumption rates of digitonin-permeabilized cultured skin fibroblasts. Therefore, the determination of maximal oxidation capacities of a well-defined cell population using strictly standardized conditions of digitonin permeabilization is judged as a useful and sensitive method for the elucidation of mitochondrial function in extramuscular tissue.

Adolescent↗
PubMed1995

Direct determination of lipoprotein(a) cholesterol by ultracentrifugation and agarose gel electrophoresis with enzymatic staining for cholesterol.

Lipoprotein(a) [(Lp(a)], a low-density lipoprotein (LDL)-like particle, contains in addition to LDL a specific protein component, apolipoprotein(a) [apo(a)]. Conventionally, Lp(a) has been measured by immunological methods that distinguish between Lp(a) and LDL by dealing with apo(a) as an antigen. We describe a new method to determine Lp(a) on the basis of its cholesterol content. Very-low-density lipoproteins were removed from serum by preparative ultracentrifugation at a density of 1.006 kg/L. The infranate was subjected to agarose gel electrophoresis to separate Lp(a) and LDL. Lp(a) cholesterol was then determined by direct enzymatic staining for cholesterol. On electrophoresis of the > 1.006 kg/L (bottom) fraction, Lp(a) migrates to the pre-beta position, regardless of the genetic apo(a) isoform. The interassay CVs of Lp(a) cholesterol determinations ranged from 6.9% to 11.5%, and the results correlated well with the Lp(a) concentrations measured by immunonephelometry (r = 0.937). There was an inverse relation between the molecular mass of the genetically determined apo(a) isoforms and Lp(a) cholesterol concentrations. Patients with angiographically proven coronary artery disease (CAD) had significantly more Lp(a) cholesterol than healthy controls did. The ratio of Lp(a) cholesterol to immunologically determined Lp(a) tended to be lower in CAD patients, suggesting that Lp(a) particles contained less cholesterol than apo(a). In addition, the new method allows determination of LDL cholesterol without contamination by Lp(a).

Adult↗
PubMed1994

Quantification of apolipoprotein A-IV in human plasma by immunonephelometry.

We developed a nephelometric procedure for determining concentrations of human plasma apolipoprotein (apo) A-IV. Results obtained correlate well with those measured by an established electroimmunodiffusion assay (r = 0.98; n = 56). Intra- and interassay CVs were 2.4% and 2.0%, respectively, indicating excellent precision and reproducibility. Various conditions of sample treatment, such as adequate storage, freezing, and thawing, did not affect results significantly. However, keeping samples at room temperature for 4 days led to a slight increase in measured values. Preincubation with a cholesterinesterase-detergent mixture abolished interference from triglyceride-rich lipoproteins, allowing assay of samples containing triglycerides as great as 10 g/L. The assay is easily applicable to clinical laboratories for routine diagnostic use, as shown with hypertriglyceridemic plasmas and samples with a broad range of apo A-IV concentrations.

Adolescent↗
PubMed1992

Postprandial pattern of triglyceride-rich lipoprotein in normal-weight humans after an oral lipid load: exaggerated triglycerides and altered insulin response in some subjects.

In 13 healthy, male nonsmokers (mean age: 25.7 +/- 2.4 years) with normal fasting triglycerides we investigated postprandial changes of triglycerides in several lipoprotein fractions. After a 12-hour overnight fast they ingested a standardized lipid load (1,017 kcal) including 30,000 IU retinyl palmitate. Postprandially, total triglycerides increased significantly (p < 0.001) to a peak value of 221 +/- 81 mg/dl at 5 h. Two subjects had an exceptionally strong triglyceride response (peak values: 363 and 390 mg/dl). They had the highest levels of retinyl palmitate in the chylomicron and the nonchylomicron fraction, and one of them showed elevated intermediate-density lipoprotein values throughout the test period. In addition, they showed an altered early and an increased late postprandial insulin response. Thus, our data provide evidence that an exaggerated postprandial triglyceride response may point to an increased atherogenic risk even in healthy subjects with normal fasting triglycerides.

Adult↗
PubMed1992

Fish oil treatment and apolipoprotein(a).

Two recent reports showed a lowering of elevated lipoprotein(a) levels upon treatment with fish oil. The aim of this paper was to confirm this finding and to establish a dose-effect relationship. A double blind, placebo controlled cross-over study was carried out in 48 subjects with apolipoprotein(a) ("Apo(a)") values between 34 and 1062 U/l (median 387 U/l). The subjects were divided into 3 groups receiving 3.5, 7.1 and 10.6 g omega-3 fatty acids/day during 28 days. Parameters measured were blood levels of eicosapentaenoic acid ("EPA"), Apo(a) and fasting blood lipids. EPA levels rose in the three dosage groups by factors 7, 9 and 14, respectively, if compared to values upon placebo. Triglycerides were significantly lowered in a dose depending manner. Apo(a), however, was not changed. This held true for different baseline Apo(a) values and different fish oil dosages. It is concluded that fish oil treatment during 4 weeks cannot lower elevated Apo(a) levels.

Adult↗
PubMed1991

Cholesterol efflux from macrophages mediated by high-density lipoprotein subfractions, which differ principally in apolipoprotein A-I and apolipoprotein A-II ratios.

High-density lipoprotein (HDL) was fractionated by preparative isoelectric focussing into six distinct subpopulations. The major difference between the subfractions was in the molar ratio of apolipoprotein A-I to apolipoprotein A-II, ranging from 2.1 to 0.5. The least acidic particles had little apolipoprotein A-II, were larger and contained the most lipid. The efflux capacity of the HDL subfractions was tested with mouse peritoneal macrophages and a mouse macrophage cell line (P388D1), either fed with acetylated low-density lipoprotein or free cholesterol. All the HDL subfractions were equally able to efflux cholesterol. The efflux was concentration dependant and linear for the first 6 h. The HDL subfractions bound with high affinity (Kd = 6.7-7.9 micrograms/ml) at 4 degrees C to the cell surface of P388D1 cells (211,000-359,000 sites/cell). Ligand blotting showed that all the HDL subfractions bound to membrane polypeptides at 60, 100, and 210 kDa. These HDL binding proteins may represent HDL receptors. In summary HDL particles, which differed principally in ratio of apolipoprotein A-I to apolipoprotein A-II behaved in a similar manner for both cholesterol efflux and cell surface binding.

Animals↗
PubMed1991

Differentiation between calcium- and cholesterol-dominated types of arteriosclerotic lesions: antiarteriosclerotic aspects of calcium antagonists.

In a series of animal studies we have clearly demonstrated since 1970 that calcium overload of the arterial wall is crucially involved in the pathogenesis of arteriosclerotic lesions. Following excessive calcium uptake, vascular stretch compliance and distensibility were lost together with structural integrity. Conversely, calcium antagonists that counteract abundant calcium uptake were found to prevent pathogenic mural calcium accumulation and damage. These effects were realized with light and electron microscopy as well as with measurements of calcium accumulation using atomic absorption spectrometry and radiocalcium. The experiments were carried out on rats exposed to various well-known risk factors such as nicotine, alloxan diabetes, high doses of vitamin D3, or dihydrotachysterol. Another particularly vasotoxic factor appeared to be hypertension, which develops in spontaneously hypertensive Okamoto rats (SHRs), in hypertensive NaCl-loaded salt-sensitive Dahl-S rats, and in rats with nephrogenic Goldblatt hypertension. Interestingly, aging arteries in animals and humans also exhibit, as a characteristic phenomenon, a steady increase in arterial calcium content. This natural age-dependent calcium accumulation is further enhanced in severe diabetics, heavy smokers, and hypertensive patients. However, the most excessive degree of toxic calcium overload, correlated with dramatic structural damage, occurred in human coronary artery plaques. Here, in "fatty streaks" (type I plaques according to World Health Organization classification), the mural calcium content exhibited a rise by 13 times above normal; in type II lesions (fibrous plaques), the increase in calcium was 24-fold; and in type III plaques, i.e., in "complicated lesions of stenosing character," calcium overload amounted to a value greater than 80 times above that found in healthy coronary segments.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1991

Rapid apolipoprotein E phenotyping by immunofixation in agarose.

Conventional determination of apolipoprotein E isomorphs comprises ultracentrifugation of 1-5 ml serum, delipidation of very low density lipoproteins (VLDL), and isoelectric focusing (IEF) in polyacrylamide gels. In order to reduce the sample volume and to avoid nonspecific protein bands, immunoblotting was proposed. Now we describe a methodological variant that uses 25 microliters serum, replaces ultracentrifugation by precipitation of apoE-containing lipoproteins with polyethylene glycol, and delipidation by dissolution in detergent. IEF is carried out in agarose. This allows specific immunofixation of apoE-containing bands with 10 microliters antiserum per sample. This method yields apoE patterns that are specific and well resolved. Also, it offers considerable savings of time and equipment involved.

Apolipoproteins E↗