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Biomedical subjects

P Sauer

Publications and source records attributed to P Sauer.

At least 55 records · Page 3Linked to original sources
PubMed1995

In patients with orthotopic liver transplantation, serum markers of cholestasis are unreliable indicators of biliary secretion.

BACKGROUND/AIMS: In patients after orthotopic liver transplantation, treatment with the novel immunosuppressant FK 506 may lead to elevated levels of alkaline phosphatase, gamma glutamyl transferase and bilirubin. Up to now it was unclear whether the excretory capacity of the liver in such patients is impaired. METHODS: We measured quantitatively the secretion of bile acids, phospholipids and cholesterol using the duodenal perfusion method, which allows assessment of biliary secretion without interruption of the enterohepatic circulation. Six healthy volunteers served as controls. RESULTS: All patients studied after orthotopic liver transplantation had elevated concentrations of serum alkaline phosphatase and gamma glutamyl transferase, whereas only half of them had slightly abnormal serum bilirubin levels. On average, the FK 506-treated patients excreted 1.23 +/- 0.27 mmol/h bile acids, 0.23 +/- 0.04 mmol/h phospholipids and 0.11 +/- 0.02 mmol/h cholesterol, which was not significantly different from the healthy controls. CONCLUSIONS: The normal secretion rates of biliary bile acids and lipids in FK 506-treated patients with elevated serum alkaline phosphatase and gamma glutamyl transferase indicate that the excretory capacity of the transplanted liver has completely recovered 2-3 months after surgery. In addition, in the majority of these patients elevated serum levels of alkaline phosphatase, gamma glutamyl transferase and bilirubin do not reflect impaired biliary secretion.

Adult↗
PubMed1995

Inhibition of ileal bile acid transport by cyclosporin A in rat.

Chronic administration of cyclosporin A may induce cholestasis and this effect has been attributed to impaired hepatic bile salt synthesis, metabolism and transport. We investigated the effect of cyclosporin A on intestinal absorption of bile acids in the ileum of rat. Ileal bile acid absorption was measured by in vivo intestinal perfusion with cyclosporin A and the solvent Cremophor EL. During ileal perfusion with 25 microM glycocholic acid, the concentration of 2.8 mM cyclosporin A inhibited intestinal bile acid absorption on average by 34%. Additional experiments were performed with everted gut sacs of the distal ileum to evaluate active absorption. A dose and time dependent inhibition of the active intestinal absorption of bile acids was found, with a 50% transport inhibition at an average cyclosporin A concentration of 2.69 mmol L-1. Thus, cyclosporin A inhibits the active intestinal absorption of bile acids which may influence bile acid synthesis, turnover and secretion and may contribute to cyclosporin A induced cholestasis.

Animals↗
PubMed1995

[Portal hypertension and percutaneous transjugular portasystemic stent shunt].

This paper reports 1) the historic development of TIPSS, the transjugular intrahepatic portosystemic stent shunt from experimental evaluation to clinical realization. 2) The evolution of the instrumental technique during a period of 6 years of clinical applications is described in detail. 3) Results based on 204 consecutive procedures are demonstrated: e.g. the early technical success defined as successful completion of the procedure and 30-day survival was 95%; the clinical success defined as technically successful procedure and no rebleeding during the first 30 days was 83%, the 30-day mortality rate was 6.3%; the 30-day encephalopathy rate was 14.1%; the one-year re-bleeding rate was 11%; the one-year survival rate was 74%, the 3-year survival rate was 41%. 4) Problems of the TIPSS procedure are discussed including a 3-months re-stenosis rate of 46% and a cumulative one-year re-stenosis rate of 84% which requires correction by interventional procedures such as shunt dilatation or additional vascular stent placement. 5) Limitations and indications of TIPSS are elucidated based on hemodynamic and functional aspects of liver cirrhosis.

Esophageal and Gastric Varices↗
PubMed1995

Biliary secretion of bile acids and lipids in primary sclerosing cholangitis. Influence of cholestasis and effect of ursodeoxycholic acid treatment.

In patients with primary sclerosing cholangitis cholestasis is a prominent feature of the disease. We studied the effect of cholestasis and of ursodeoxycholic acid treatment on the biliary secretion of bile acids and lipids in ten patients with primary sclerosing cholangitis. Ursodeoxycholic acid treatment for 3 months led to an increase in the biliary secretion rates of total bile acids from 0.91 mmol/h to 1.47 mmol/h, mainly due to an increase in urosodeoxycholic acid, which represented 31% of biliary bile acids. With increasing cholestasis, the biliary enrichment of the bile acid pool with urosodeoxycholic acid decreased. Biliary output of endogenous bile acids on average was unchanged, but in patients with cholestasis and diminished output before treatment, it increased after ursodeoxycholic acid. Phospholipid secretion increased from 0.26 mmol/h to 0.43 mmol/h without correlation to the degree of cholestasis. Biliary cholesterol secretion on average was unchanged after ursodeoxycholic acid (0.1 versus 0.09 mmol/h) but, in patients with cholestasis and diminished output before treatment, it increased after ursodeoxycholic acid. The decreasing enrichment of the bile acid pool with ursodeoxycholic acid with increasing cholestasis may be related to its slight effect in advanced disease. The increase in biliary phospholipid secretion may represent another mechanism of action of urosodeoxycholic acid responsible for its beneficial effect in cholestatic liver disease.

Adolescent↗
PubMed1994

Comparison of a semiquantitative and a quantitative method for assessing vertebral fractures in osteoporosis.

There is no agreed definition for the assessment of vertebral fractures and deformities in patients with osteoporosis. Radiographs of 66 patients randomized for therapy with etidronate or placebo were analyzed at baseline and during follow-up (60/120/150 weeks) independently using two procedures. The first method of spinal deformity index (SDIG) and vertebral deformity score (VDSG) is based on a semiquantitative visual reading of each vertebra between T4 and L4. The second method of spine deformity index (SDIM) and vertebral deformity index (VDIM) is based on vertebral height measurements of T4 through L5 and each measurement from T5 to L5 (anterior, middle and posterior height) is related to T4 and compared with the respective T4-related normal range. There was good agreement between the mean vertebral deformation from T5 to L4 graded by VDSG and VDIM, with correlation coefficients between R = 0.52 (p < 0.0001) and R = 0.9 (p < 0.0001) respectively. Spinal deformation at baseline as measured by SDIM and SDIG was correlated with R = 0.76 (p < 0.0001). For diagnosing a vertebra as fractured or not, VDIM reached a sensitivity of 82% and a specificity of 85% using VDSG as a standard, and on the other hand VDSG reached a sensitivity of 78% and a specificity of 88% in relation to VDIM. The changes in spinal deformation from week 0 to 150 were correlated with R = 0.58 (p < 0.0002) between SDIM and SDIG. To detect vertebral fracture progression the sensitivity of VDIM was 74% and the specificity 86%, when changes in VDSG were used as a standard.(ABSTRACT TRUNCATED AT 250 WORDS)

Etidronic Acid↗
PubMed1994

[Transjugular intrahepatic portasystemic stent shunt (TIPSS). Indications and postoperative management].

Complications of portal hypertension, e.g. bleeding from esophageal or gastric varices or ascites, can be efficiently treated by transjugular intrahepatic portosystemic stent shunting. The most important and most frequently encountered contra-indications to this procedure are malignant liver tumors, systemic infections or hepatic decompensation, and encephalopathy. Before and after the shunt procedure, treatment of these patients must be selected and administered with due consideration for the fact that they extremely prone to bacterial infections and have many concomitant diseases, e.g. impaired renal function. To prevent early occlusion of the stent, patients receive anticoagulants in the first few days after the procedure.

Esophageal and Gastric Varices↗
PubMed1994

[Transjugular intrahepatic portasystemic stent shunt (TIPSS). Results and complications].

Use of a transjugular intrahepatic portosystemic stent shunt (TIPSS) is a highly efficient method of controlling bleeding from esophageal or gastric varices in patients with portal hypertension. Early mortality is between 2% and 13%. Stenosis and occlusion of the stent are reported in 6-56% and 7-9%, respectively, within the first year. Stenoses occur more often in patients with good liver function. In 17-27% de novo encephalopathy is observed. The rate correlates with the extent of liver cirrhosis, which is the main factor that determines prognosis of the patients in the long run. All patients with liver cirrhosis classified as Child A were alive after 1 year, in contrast to only 51% of patients with Child C cirrhosis.

Adult↗
PubMed1994

Acetylsalicylic acid in the prevention of early stenosis and occlusion of transjugular intrahepatic portal-systemic stent shunts: a controlled study.

Stenosis or occlusion of the transjugular intrahepatic portal-systemic stent shunt may be initiated by aggregation and activation of thrombocytes on the surface of the metallic stent material. To find effective prevention of this event, we conducted a controlled trial administering acetylsalicylic acid for 3 mo. Forty-four patients (8 women and 36 men) with portal hypertension were included in this study. The patients were randomized into a group receiving 100 mg acetylsalicylic acid/day (n = 21) or into a control group (n = 23). Treatment was started immediately after transjugular intrahepatic portal-systemic stent shunt. Three months after transjugular intrahepatic portal-systemic stent shunt, 15 patients in the acetylsalicylic acid group and 19 patients in the control group underwent clinical reevaluation, gastroscopy and recatheterization with determination of the portal-systemic pressure gradient. No variceal bleeding occurred in any patients. In four patients in the acetylsalicylic acid group, erosive gastritis was observed in gastroscopy in contrast to only one patient in the control group. Complete patency of the stent was noted in 10 of 15 patients in the acetylsalicylic acid group and in 14 of 19 patients in the control group. Transjugular intrahepatic portal-systemic stent shunt restenosis associated with a significant increase of the portal-systemic gradient occurred in five patients in the acetylsalicylic acid group, which required redilation in all and additional stent placement for expansion of the stented tract in two patients. In the control group, redilation was necessary in five patients with additional stent extension in two patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1993

[Acute arterial occlusion of the upper extremity by tumor embolism].

We present a case of acute occlusion of the right branchial artery in a 56-year-old male caused by bronchogenic tumor embolus as the first manifestation of malignancy. The primary tumor was shown to be inoperable and rapidly formed metastases in skin and liver. The case presented demonstrates, that embolic events originating from malignant tumor cells are characteristic for organ-exceeding tumor growth. Thus the prognosis is generally poor.

Arm↗
PubMed1992

The effect of beta blocking drugs on lipid peroxidation in rat heart in vitro.

Beta-adrenergic receptor blocking drugs include a structurally related class of drugs that are employed clinically to treat a variety of cardiovascular disorders. Since these drugs exert additional nonspecific effects including membrane stabilization, representative samples including atenolol, dilevolol, labetalol, metoprolol and propranolol were studied to determine their influence on lipid peroxidation. Homogenates or liposomes of adult rat hearts were incubated in the presence of various concentrations of propranolol or equivalent concentrations of dilevolol, labetalol, metoprolol or atenolol. Lipid peroxidation was stimulated with 50 microM FeSO4, 5 microM t-butyl hydroperoxide (homogenates) or 0.2 mM citrate FeSO4 (liposomes) plus O2. Lipid peroxidation, as assessed by both the thiobarbituric acid reaction and chemiluminescence, was reduced in a dose-dependent manner as the propranolol concentration was increased from 1 to 10 mM. The five beta-adrenergic receptor blocking drugs reduced lipid peroxidation both in crude homogenates and in liposomes; their effectiveness was related to their lipophilicity. Dilevolol, propranolol, labetalol and metoprolol at a concentration of 20 mM reduced lipid peroxidation by 45%, 37%, 35% and 28%, respectively. The hydrophilic blocker atenolol was ineffective in reducing lipid peroxidation even at elevated concentrations. Lipophilic beta-blocking drugs apparently are capable of exerting an antioxidant effect in protecting membrane lipids against peroxidation.

Adrenergic beta-Antagonists↗
PubMed1991

Spine deformity index (SDI) versus other objective procedures of vertebral fracture identification in patients with osteoporosis: a comparative study.

Radiologic identification of vertebral fractures is most important in the diagnosis and monitoring of patients with spinal osteoporosis. Different methods, using vertebral height measurements for fracture identification, have therefore been developed. We compared four methods for fracture identification in spinal x-rays of 62 female patients with primary osteoporosis. The methods of Hedlund and Gallagher, Melton et al., and Davies et al. are based on the ratio of heights within one vertebra or of the height ratios of adjacent vertebrae; all three methods result in counting the number of vertebral fractures. The fourth method of Minne et al. relates anterior, middle and posterior heights of the vertebrae between T5 and L5 to the respective heights of T4. The relative vertebral heights of patients with osteoporosis are compared to the respective relative heights (anterior, middle, and posterior) of normal subjects (T5-L5). This allows the identification of fractured vertebrae, as well as a quantification of the extent of deformation due to these fractures (spine deformity index, SDI). The same measurement data of 62 spinal x-rays of anterior, middle, and posterior heights between T4 and L5 were used to detect vertebral fractures by the four different methods. Correlation between the number of identified fractures by the different methods ranged between r = 0.56 and 0.83. On the other hand, we found a remarkable difference in the mean number of identified fractures and a discrepancy in the identification of single vertebrae as fractured or not. All four methods revealed an accumulation of fractures in the midthoracic area and in the region of transition from thoracic to lumbar spine. Vertebral fractures as identified by SDI were not detected by the other three methods in 12-29% of the cases, even if vertebral height reduction was more than 6 mm. The reliability of each method was examined by the determination of "decreasing" number of fractures during follow-up. A decrease in the number of fractures was found in about 25% patients, if using the three methods that count only the number of fractures. We obtained a 3.6% decrease in the number of fractures using the fourth method. Furthermore, the decrease in SDI values in follow-up was within the range of variance. We therefore believe that SDI and related procedures are reliable in quantifying spinal osteoporosis and monitoring during follow-up.

Adult↗
PubMed1990

A study of complaints and their relation to vertebral destruction in patients with osteoporosis.

Patients with spinal osteoporosis suffer from vertebral deformation, loss of height and back pain, as well as from functional limitations and alterations of mood. So far little is known about the extent of these clinical symptoms at all and whether they are related in a predictable manner to the fractures or damages of bone structure. In the present study we investigated the relation between vertebral deformation and clinical symptoms in 70 patients with osteoporosis. Clinical data like pain, functional limitations and parameters of mood were examined by a standardized questionnaire. The numbers of vertebral fractures were determined, and the vertebral destruction was quantified using the Spine Deformity Index (SDI). The symptoms and functional limitations were graded and correlated to the SDI and the number of fractures. Our results underline a relation between the extent of vertebral deformation and the reduction in quality of life by pain, functional limitations and alterations of mood. This relationship was absent or less evident, if the number of fractures was taken into account. Besides the difficulties concerning the grading and quantification of clinical symptoms and outcome of disease, our study revealed that there is a causal relation between the extent of vertebral destruction measured by the SDI and the extent of these clinical parameters.

Adult↗
PubMed1989

SOD-1 activity and platelet membrane fluidity in Alzheimer's disease.

An early-onset, familial form of Alzheimer's disease (AD) has been reported to be linked to a locus on the long arm of chromosome 21 (21q21). Furthermore, duplications in the vicinity of this locus involving the beta-amyloid gene and the proto-oncogene ets-2 have been reported in association with AD. The structural gene for Cu,Zn superoxide dismutase, SOD-1, is located between the beta-amyloid gene and ets-2. For this reason and because SOD-1 is a plausible candidate for a gene that might influence the fluidity of cellular membranes, we determined whether or not the subtype of AD with increased platelet membrane fluidity was associated with an increase in Cu,Zn superoxide dismutase activity.

Aged↗
PubMed1989

Total-body protein turnover in parenterally fed neonates: effects of energy source studied by using [15N]glycine and [1-13C]leucine.

The effects of nonprotein energy source (ie, glucose only vs glucose and lipid) on nitrogen retention and total-body protein turnover were studied in 20 parenterally fed newborn infants. All infants received approximately 3 g amino acids and 80-90 kcal.kg body wt.d. Total-body protein synthesis was estimated by using three constant-infusion, end-product methods: enrichment of urinary urea and ammonia in response to a [15N]glycine label and exhaled carbon dioxide enrichment in response to a [1-13C]leucine label. No differences were seen in nitrogen retention between the two energy sources. The estimate of total-body protein turnover obtained from the 13C label was similar to that obtained with the [15N]urea label. No differences in turnover rates were observed between the two diet groups. Use of the glucose-plus-lipid fuel system enhanced energy storage and the reutilization of amino acid for protein synthesis.

Ammonia↗
PubMed1989

A comparison of the estimates of whole-body protein turnover in parenterally fed neonates obtained using three different end products.

Protein turnover rates in neonates have been calculated largely by measuring urinary [15N]urea enrichment following administration of [15N]glycine. Although ammonia has been increasingly recognized as an end product of nitrogen metabolism, in neonates it yields a different estimate of protein turnover than does urea. Comparisons of ammonia and urea end products in parenterally fed neonates have not previously been reported. A third and independent way of estimating protein turnover, developed for adults, is to use breath 13CO2 as an end product following administration of [1-13C]leucine. We therefore carried out simultaneous measurements of protein turnover in 10 parenterally fed neonates, using the three end products. The infants were clinically stable, weighed 2.6 +/- 0.2 kg, and received 3.1 +/- 0.2 g.kg-1.d-1 of amino acid, 2.2 +/- 0.1 g.kg-1.d-1 of lipids, and an energy intake of 90 +/- 4 kcal.kg-1.d-1 (1 kcal = 4.186 kJ). The turnover estimates derived from the 13CO2 and [15N]urea end products were very similar. The [15N]ammonia end product produced values approximately 66% (p less than 0.01) of the other two. We conclude that the ammonia and urea end products probably originate in different precursor pools. The similarity of the urea and breath carbon dioxide results helps validate the use of the urea end product in studying the nitrogen metabolism of parenterally fed neonates. Ideally in future studies two or more end products should be used, since they provide information about different aspects of the neonates' protein metabolism.

Amino Acids↗