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K Samuelson

Publications and source records attributed to K Samuelson.

At least 19 recordsLinked to original sources
PubMed1992

Serum primary bile acids in the course of celiac disease in children.

Serum concentrations of primary bile acids (BAs) were determined in the course of celiac disease and in healthy age-matched controls. Determinations of BAs were made by radioimmunoassays after an overnight fasting and for 4 h postprandially after intake of a standardized test meal. In untreated celiac disease presenting with subtotal villous atrophy, peak concentrations of primary BAs were significantly delayed and serum levels were significantly higher than in controls. Small but significant abnormalities persisted after a period of gluten-free diet despite a normalization of mucosal morphology. Slightly pathological standard liver function tests in five patients were related to increased fasting levels but not to the postprandial pattern of BAs, indicating that the observed abnormalities postprandially were not related to liver disease. Further studies simultaneously focusing on deconjugation mechanisms, absorption, and pool sizes of BAs are required to explain the postprandial BA pattern under the course of celiac disease.

Adolescent↗
PubMed1992

Blood pressure reduction during hemodialysis correlates to intradialytic changes in plasma volume.

Blood pressure alterations during hemodialysis were related to changes in body fluid in 14 patients with chronic renal failure. Changes in plasma volume (PV) and extracellular volume (ECV) were calculated from determinations of fluid volumes before and after hemodialysis, using 125I-albumin and 51Cr EDTA respectively. Reduction in body water was estimated from body weight changes. Weight loss was 3.3 +/- 0.3 kg (range 1.8-6.0 kg). The relative reduction of fluid was greater in the ECV, 21.6 +/- 3.2%, compared to plasma volume, 6.9 +/- 1.8%. The reduction in systolic blood pressure was related to both absolute (r = 0.66, p less than 0.05) and relative PV reduction (r = 0.72, p less than 0.02). There was no correlation between blood pressure reduction and weight loss or ECV changes. Only minor alterations were found in diastolic blood pressure. Plasma volume maintenance relates to blood pressure changes. Plasma volume monitoring could be useful for improving intradialytic hemodynamic control.

Adult↗
PubMed1990

Whole body impedance measurements reflect total body water changes. A study in hemodialysis patients.

Fluid volume changes during hemodialysis was monitored by continuous whole body impedance measurements. The fluid changes recorded using this method was compared to fluid volume changes measured in plasma water (PV) using 125I-albumin, and extracellular volume (ECV) using 51Cr-EDTA before and after treatment, and total body water (TBW) changes reflected by continuous bed scale monitoring. Changes in impedance correlated to TBW changes, r = 0.80, p less than 0.001, while correlations to changes in ECV and PV were: r = 0.57 and r = 0.55, respectively, p less than 0.05. Alterations in body fluid volumes recorded with whole body impedance is best correlated to total body water changes. The use of continuous whole body impedance monitoring has been shown to offer a simple non-invasive method for recording total body water changes during hemodialysis.

Aged↗
PubMed1990

Relationship between interdigestive gallbladder emptying, plasma motilin and migrating motor complex in man.

The aim of this study was to elucidate the importance of biliary output for the regulation of migrating motor complex and the release of plasma motilin. Gallbladder emptying was monitored by hepatobiliary scintigraphy, plasma motilin concentration by radioimmunoassay and gastrointestinal motility by a perfused catheter system. During a total recording time of 46 h and 20 min in 16 volunteers, we observed 29 episodes of gallbladder emptying, 27 plasma motilin peaks and 23 activity fronts (phase 3 activity) of the migrating motor complex (MMC). Twelve episodes of gallbladder emptying started in phase 1 and continued into phase 2 of the MMC. The remaining 17 episodes of gallbladder emptying started in phase 2, and three of these continued into phase 3 of the MMC. Biliary output was associated with a significant rise in plasma motilin concentration, whereas plasma motilin significantly decreased after the activity fronts. These observations may explain the well-known fluctuations of plasma motilin concentration in the fasted state. Motilin is released into the circulation as a result of biliary output, while the ensuing activity front of the MMC removes this stimulant from the proximal small bowel, resulting in a fall in plasma motilin. In conclusion, we have confirmed a temporal relationship between biliary output into the duodenum and the release of plasma motilin. The observed transition from phase 1 to phase 2 and from phase 2 to phase 3 of the MMC during gallbladder emptying episodes suggests that biliary output stimulates gastrointestinal motility in the fasted state.

Adolescent↗
PubMed1990

An all-polyethylene cementless tibial component. A five- to nine-year follow-up study.

An all-polyethylene cementless tibial component was used in 221 total knee arthroplasties. With one exception, failures did not occur before three years. Failure was characterized by medial subsidence of the tibial component. There was abrasion of the polyethylene on the undersurface of all components that failed. Survivorship was seven to nine years (87.1%). This study demonstrated that a flexible cementless component can function well when used with any type of bone. However, abrasion of the polyethylene that occurs from shearing forces is a concern. Polyethylene components need adequate provisions to prevent shearing or need surface treatment to prevent abrasion.

Adult↗
PubMed1985

Fasting serum bile acid levels in relation to liver histopathology in cystic fibrosis.

The fasting serum concentrations of primary bile acids were determined in 30 patients with cystic fibrosis, aged 1 to 27 years, and correlated to liver disease. Cholic (fs-C) and chenodeoxycholic (fS-CDC) acids were determined by radioimmunoassays. Two patients had biopsy-proven liver cirrhosis, 13 had portal fibrosis. 8 had minor different pathological changes, and 7 had normal liver morphology. Standard liver function tests were of no help in evaluating liver disease in these patients. Eight patients had increased fS-C and 15 had increased fS-CDC, not correlated to liver morphology. Serum bile acid determination seems to be of no value in evaluating the extent of liver disease in cystic fibrosis. The more frequent and more marked increase of fS-CDC than of fS-C suggests that there is another hepatic clearance of bile acids in CF and/or that intestinal factors have a greater influence on the serum bile acid concentrations in this disease.

Adolescent↗
PubMed1985

The point is...

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Communication↗
PubMed1984

Estriol and cholic acid in maternal serum in induced labor.

Prostaglandin E2 (PGE2), but not oxytocin, treatment to induce parturition brought about an increase (p less than 0.001) in maternal serum levels of total estrogens (conjugated and nonconjugated estriol). There was no increase in nonconjugated estriol. To explore if the changes were related to an altered enterohepatic circulation, cholic acid assay in maternal serum was used. There were no changes in cholic acid which parallelled those in total estrogens. It is concluded that PGE2 does not appear to affect enterohepatic circulation of steroids, and it is suggested that the increase in total estrogens may be caused by changes in the kidney excretion of estriol.

Adolescent↗
PubMed1984

Evaluation of two enzymatic methods of determining unsulphated serum bile acids.

Two enzymatic methods of determining unsulphated 3 alpha-hydroxylated and 7 alpha-hydroxylated bile acids, respectively, were evaluated. Both methods are based on a coupled enzyme reaction involving a coloured redox indicator and absorbance measurement as the final step. Recovery and specificity were tested on human serum pools containing different bile acids added in various amounts, and by comparison of the results with those obtained by gas-liquid chromatography after group separation of bile acids from patient sera. Results from the two enzymatic methods were also compared with those determined with radioimmunoassay on a large number of patient sera. The results indicate that the enzymatic methods are useful for serum bile acid screening but more sensitive methods are necessary for investigations within the normal range.

3-Hydroxysteroid Dehydrogenases↗
PubMed1984

An enzymatic method of determining 7 alpha-hydroxylated bile acids in urine.

A recently developed enzymatic method of determining unsulphated 7 alpha-hydroxylated bile acids in serum was evaluated for the analysis of bile acids in urine after hydrolysis of the sulphate esters. Results obtained using the enzymatic method were compared to those obtained by radioimmunoassay of 7 alpha-hydroxylated bile acids in urine samples from patients. Results of the enzymatic method were also compared to results of gas-liquid chromatography of individual bile acids after group separation of the bile acids on Sephadex-DEAP-LH-20. There was significant correlation between the enzymatic method and radioimmunoassay for bile acid determination in urine. The analysis of different conjugates after group separation of bile acids revealed no unspecific reactions when compared to gas-liquid chromatography. The reference range for 7 alpha-hydroxylated urinary bile acids was in agreement with earlier published results.

Bile Acids and Salts↗
PubMed1984

Studies on the causal relationship between gall-bladder emptying and motilin release in man.

Emptying of the human gall-bladder has previously been shown to be associated with the release of motilin, both in the fasting state and after various stimuli, such as oral intake of fat or water. Whether motilin causes emptying of the human gall-bladder or whether the peptide is released by gall-bladder emptying is not presently known. Recent animal experiments suggest that intravenous infusion of pure porcine motilin causes emptying of the gall-bladder, both in the pig and the dog. In the present investigation, neither a physiological nor a pharmacological one-hour infusion of pure porcine motilin caused emptying of the human gall-bladder. In contrast, manual compression of the gall-bladder, at the beginning of operation for large bowel carcinoma, was followed by motilin release. The one-hour integrated motilin response after gall-bladder compression was about 10 times greater than in the control patients in whom the motilin response after palpation of the liver was similarly calculated. We conclude that flow of bile into the proximal small bowel is a signal for the release of motilin from the peptide-producing cells in the gut mucosa.

Bile Acids and Salts↗
PubMed1983

Cholic and chenodeoxycholic acids during drainage of cholestasis in man with and without bile refeeding. Determination of serum and urinary concentrations by radioimmunoassay.

Non-sulphated conjugates of cholic (C) and chenodeoxycholic (CDC) acids in serum and total conjugates in urine were determined by radioimmunoassay during drainage of extrahepatic cholestasis in twelve patients studied under three different situations: without refeeding of bile, with refeeding after a delay of one to eight days, and with immediate refeeding. The changes in the serum concentrations and renal excretion of C and CDC varied considerably between patients, but the following general features could be discerned: In patients without bile refeeding but with external drainage, the serum concentrations and renal excretion of C and CDC decreased rapidly. In patients with delayed bile refeeding during drainage, the serum concentrations of C and CDC increased when refeeding of bile was begun but only slightly and temporarily, and no influence on renal excretion could be observed. In patients with immediate bile refeeding through an internal drainage the serum concentrations decreased slowly and renal excretion increased during the first week. These differences in the pattern of serum bile acid concentrations were not reflected in the serum concentrations of bilirubin, alkaline phosphatase, alanine aminotransferase or gamma glutamyltransferase.

Aged↗