bluuebunny/crossref_metadata_2025 huggingface dataset:
The effect of feeding and fasting on the activity of acyl‐CoA:cholesterol acyltransferase in rat small intestine
Authors: HELGERUD PER , HAUGEN RUTH , NORUM KAARE R.
Published: March 2008

Abstract. The purpose of the present study was to test if the microsomal acyl‐CoA:cholesterol acyltransferase (ACAT) in rat small intestine is regulated under physiological conditions. Two previously described in vitro assays were used, both based on the esterification of endogenous cholesterol with exogenous acyl‐CoA, preformed or generated during the incubation. The important and consistent finding with rats on normal diet was an increase in ACAT activity with fasting and a decrease with feeding. Independent of the assay used, the ratio between ACAT activity in night‐fasted and night‐fed animals was about 2 (P< 0·005). When the fasting period was extended to 36 h a corresponding difference was found whether the ACAT assay was based on preformed [1‐14C]oleoyl‐or [1‐14C]palmitoyl‐CoA as acyl‐donor (P < 0·05). The microsomal content of unesterified cholesterol was higher in fasted than fed animals, suggesting that availability of this substrate might be a factor in the regulation of rat intestinal ACAT activity.
Vitamin D metabolites in post‐menopausal women and their relationship to the myopathic electromyogram
Authors: HEYBURN PHILIP J. , PEACOCK MUNRO , CASSON IAN F. , CRILLY RICHARD G. , TAYLOR GEOFFREY A.
Published: March 2008

Abstract. Proximal muscular weakness is a feature of many metabolic bone diseases but is not well recognized in spinal osteoporosis. Thirty‐six post‐menopausal women presenting with back pain, with or without osteoporosis, were therefore studied in order to define the relationship between abnormal electromyographic findings and disturbed vitamin D metabolism, as both low plasma 1,25 dihydroxy vitamin D concentrations and malabsorption of calcium have been reported in osteoporosis.

Patients with abnormal electromyograms had lower concentrations of plasma 1,25 dihydroxy vitamin D (mean 78.3 pmol/1, SD 20.5, n=15) than normal subjects of similar age (mean 110.4 pmol/1, SD 39.4, n= 21; P<0.01), but electromyographic abnormality was not associated with changes in radiocalcium absorption, plasma 25 hydroxy vitamin D, plasma calcium or phosphate or urinary calcium or hydroxyproline excretion or impaired renal function. There was no relationship between abnormal electromyography and osteroporosis assessed by spinal radiographs and iliac crest biopsy.

These findings are consistent with our previous suggestion that muscle weakness in many unrelated bone disorders is related to low plasma 1,25 dihydroxy vitamin D concentrations, but suggest that there is no relationship between proximal myopathy and spinal osteoporosis in post‐menopausal women.
The acute phase response and its relation to amyloid A degrading activity in serum of patients with rheumatoid arthritis undergoing arthroplasty
Authors: MAURY C. P. J. , TEPPO A‐M. , RAUNIO P.
Published: March 2008

Abstract. The sequential changes in the concentration of specific serum proteins and their relation to amyloid A degrading activity were studied in ten patients with rheumatoid arthritis undergoing arthroplasty of the knee or hip. Serum amyloid A protein increased from a preoperative level of 78 ± 20 gm/1 (mean ± SEM) to a peak level of 623 ± 93 mg/1 on the third postoperative day (P<0.001). The serum amyloid A protein response was greater than that of any other protein including C‐reactive protein, to which it was closely related (r= 0.84, P<0.001). The concentrations of α1‐antitrypsin and α1antichymotrypsin were highest on the fourth postoperative day (mean changes 35%, P<0.01, and +44%, P<0.05, respectively). Serum albumin, pre‐albumin and α2‐macroglobulin behaved like negative acute phase reactants; the concentrations of albumin and α2‐macroglobulin were significantly decreased from the second to sixth and seventh postoperative days, respectively, and the concentration of pre‐albumin was significantly decreased on the third and fourth postoperative days. A significant fall in the amyloid A degrading activity of serum occurred during the acute phase reaction. The degradative activity was lowest on the third and fourth postoperative days (P<0.001).

The results show that the acute phase state in patients with rheumatoid arthritis induces a rise in the concentration of serum amyloid A protein, the putative serum precursor of tissue amyloid A fibrils, and a concomitant reduction in the ability of serum to degrade these fibrils. These factors together may be important in the development of inflammation‐associated amyloidosis.
Modes of action of lipid‐lowering diets in man: studies of apolipoprotein B kinetics in relation to fat consumption and dietary fatty acid composition
Authors: CORTESE C. , LEVY Y. , JANUS E. D. , TURNER P. R. , RAO S. N. , MILLER N. E. , LEWIS B.
Published: March 2008

Abstract. The mechanisms by which dietary fat influences fasting plasma lipid concentrations have been investigated in hyperlipidaemic subjects. The synthetic and fractional catabolic (FCR) rates of the apoprotein B (apo B) of very‐low density (VLDL) and low‐density (LDL) lipoproteins were measured using radioiodinated autologous lipoproteins.

Reductions of LDL concentration in eight subjects during low‐fat(25% of energy) diets were largely explained by diminished synthesis(‐20%, P<0.02), and possibly also by an increased FCR +15%, P= 0.05) of LDL, compared with observations made during a high‐fat (45% of energy) diet of similar fatty acid composition. VLDL apo B synthesis and FCR were not significantly altered.

When a diet rich in polyunsaturated fatty acids was exchanged for one high in saturated fatty acids (fat providing 45% of energy on both occasions) in four subjects, the synthetic rates of both VLDL apo B (‐31%, P<0.02) and LDL apo B (‐23%, P<0.10) were reduced while their FCRs were unchanged.
Bile acid metabolism in hypothyroid subjects: response to substitution therapy
Authors: ANGELIN BO , EINARSSON KURT , LEIJD BARBRO
Published: March 2008

Abstract. Bile acid kinetics and biliary lipid composition were determined in ten hypothyroid patients before and after treatment with L‐thyroxine. Hypothyroid patients had normal synthesis rates of cholic acid and chenodeoxycholic acid. Hormone treatment, which lowered plasma cholesterol by about 35%, stimulated the formation of chenodeoxycholic acid by about 40% but did not significantly change the synthesis of cholic acid or total primary bile acids. The mean relative biliary concentration of deoxycholic acid was decreased from 30% to 19% and that of chenodeoxycholic acid was concomitantly increased. Cholesterol saturation of bile was decreased by treatment in six of the patients, but the mean value before treatment (135 ± 13%) was not significantly different from that obtained after treatment (108 ± 9%). It is suggested that the hypocholesterolaemic effect of thyroid hormones is not primarily due to an increased degradation of cholesterol to bile acids. Similar to what is observed in heterozygous familial hypercholesterolaemia, the defective receptor mediated degradation of plasma low density lipoproteins in hypothyroidism is thus apparently associated with a quantitatively normal catabolic rate of cholesterol to bile acids.
Determination of cardiac and plasma drug levels during long‐term amiodarone therapy
Authors: DEBBAS NADIA M. G. , CAILAR CLAUDE DU , SASSINE ANTOINE , DERANCOURT JEAN , DEMAILLE JACQUES G. , PUECH PAUL
Published: March 2008

Abstract. A study of plasma and cardiac concentrations of amiodarone during the course of long‐term oral therapy was made possible by the improvement of analytical high performance liquid chromatography of plasma and tissue extracts.

The plasma level was found to increase linearly with the daily dose of the drug, above a threshold value of c. 1.9 mg kg‐1 day‐1. Similarly, the cardiac content increased linearly with the daily dose, with no threshold, showing that the drug is taken up and accumulated in the cardiac tissue, with no obvious difference between atrial and ventricular samples (P > 0.05). Both plasma and heart showed no saturation at high drug intake, a justification for increasing the oral intake in severe cases. The linear relationship between tissue and blood concentrations allows a prediction of the cardiac level from a simple and routine blood analysis.
Human chorionic gonadotropin and alpha chain of glycoprotein hormones in patients with inflammatory bowel disease
Authors: KRUIS W. , MANN K.
Published: March 2008

Abstract. In twenty patients with Crohn's disease and ten patients with ulcerative colitis serum levels of human chorionic gonadotropin and the common alpha‐subunit of glycoprotein hormones were determined by radioimmunoassay. In contrast to published data, all serum samples except one revealed levels within the normal range of 148 controls (human chorionic gonadotropin levels up to 3.9 μU/l, alpha‐subunit up to 3.8 μg/l). Neither the serum levels of human chorionic gonadotropin nor of the alpha‐subunit differed significantly between patients with Crohn's disease (median/maximum: 0.9/4.4 IU/l; 0.7/3.6 μg/l) and ulcerative colitis (1.0/3.4 IU/l; 0.8/2.2 μg/l). Furthermore, the serum levels studied in patients with active (0.9/3.0 IU/l; 0.7/3.5 μg/l) and inactive (0.9/4.4 IU/l; 0.8/3.6 μg/l) Crohn's disease and in patients with active (1.1/3.4 IU/l; 0.9/2.2 μg/l) and inactive (0.9/2.9 IU/l; 0.8/1.3 μg/l) ulcerative colitis were not significantly different. There was no relationship of the duration of the disease or a bowel resection to the serum levels of human chorionic gonadotropin or the alpha‐subunit. It is concluded that both parameters are not useful as markers in patients with Crohn's disease or ulcerative colitis. The normal serum levels found in patients with inflammatory bowel diseases indicate human chorionic gonadotropin as a highly specific marker for malignant diseases.
Hydrocortisone decreases the internalization of low density lipoprotein in cultured human fibroblasts and arterial smooth muscle cells
Authors: HENZE K. , CHAIT A. , ALBER J. J. , BIERMAN E. L.
Published: March 2008

Abstract. The effect of hydrocortisone on the cellular low density lipoprotein (LDL) pathway was studied in cultured human skin fibroblasts and arterial smooth muscle cells. Hydrocortisone decreased both uptake and degradation of 125I‐LDL. LDL binding, measured at 4°C, was not affected by the hormone. Physiological concentrations of hydrocortisone (4.1 ± 10‐8 mol/1) resulted in a 30% reduction of LDL uptake and degradation which could not be accounted for by an effect of the hormone on macromolecular synthesis, cell protein or cell number. To test whether the decrease in uptake and degradation of 125I‐LDL was due to reduced internalization, the effect of hydrocortisone on the internalization of prebound LDL was determined and found to be decreased. Also, preincubation with unlabelled LDL in the presence of hydrocortisone resulted in less down regulation of LDL receptor activity than when no hydrocortisone was present. An effect of the hormone on bulk phase endocytosis has been excluded, since hydrocortisone did not affect either LDL degradation by receptor negative cells or endocytosis of 14C‐sucrose by normal skin fibroblasts.

Thus, hydrocortisone impairs LDL catabolism by decreasing the internalization of LDL normally bound to its cell surface receptor. These results may be relevant to the pathogenesis of atherosclerosis in conditions associated with reduced cellular LDL catabolism.
The normal occurrence of two molecular forms of the eight complement component (C8) and their concentrations in a family with C8 deficiency
Authors: BRANDSLUND I. , TEISNER B. , STRATE M. , GRUNNET N. , SVEHAG S‐E. , ISAGER H. , WANG P.
Published: March 2008

Abstract. A haemolytically inactive alpha‐mobile complement C8 component was identified by crossed immunoelectrophoresis in a 27‐year‐old male with recurrent meningococcal infections and absence of complement mediated serum haemolytic activity. The patient's serum/plasma contained no demonstrable normal C8. C8 inhibitor activity was not demonstrable in his serum and the alternative activation pathway appeared to be intact. Serum from the proband's parents and both siblings had normal total haemolytic complement activity and they were without symptoms. However, both the normal and the haemolytically inactive C8 protein were demonstrable in their sera. Their normal C8 concentrations were less than one‐half of the normal C8 mean value and distinctly below the lowest value found in ten healthy persons. The concentration of the inactive C8 component in the proband's serum was roughly 1.5 times higher than that of the other family members, whereas its concentration in sera of the family members was between 1.8 and 2.5 times the highest concentration found in ten healthy donors, all of whom also had an alpha‐mobile C8 in measurable quantities.
Faecal bile acid analysis and intestinal absorption in Crohn's disease before and after ileal resection
Authors: FIASSE R. , EYSSEN H. J. , LEONARD J. P. , DIVE CH.
Published: March 2008

Abstract. Faecal bile acids were analysed by gas chromatography in 104 patients. Total bile acids exceeded 1.5 mmol/24 h in 33% of forty‐five unoperated patients and in 90% of those having undergone an ileal resection. Lithocholic and deoxycholic fractions were lower in the unoperated patients than in the control group (P < 0.05 and P < 0.005) and much lower after ileal resection than in unoperated patients (P < 0.001). A significant correlation (r= 0.58; P < 0.001) was found between total bile acids and relative proportions of primary bile acids in operated patients, untreated by antibiotics or sulfasalazine. Dihydroxy bile acids (predominantly chenodeoxycholic acid) correlated with faecal weight in unoperated patients (r= 0.47, P < 0.01) and in 0–50 cm (r= 0.69, P < 0.001) and 50–100 cm (r= 0–63, P < 0.01) ileal resection groups. Our results suggest that the frequently altered bile acid composition is related to a shortening of colonic transit time which reduces the exposure of primary bile acids to bacterial 7α‐dehydroxylase.
The influence of total hepatectomy on cerebral energy state, ammonia‐related amino acids of the brain and plasma amino acids in the rat
Authors: HOLMIN T. , AGARDH C.‐D. , ALINDER G. , HERLIN P. , HULTBERG B.
Published: March 2008

Abstract. The influence of total hepatectomy on cerebral energy state, ammonia‐related amino acids of the brain tissue and plasma amino acids was studied in anaesthetized rats after total hepatectomy. The hepatectomy was performed with the aid of a microsurgical three‐stage procedure. In the first stage, division of the inferior vena cava was performed. In the second stage 4 weeks later a porta‐caval anastomosis was constructed, followed after 1 week by a total hepatectomy.

The brain energy state, defined as the concentrations of phosphocreatine, ATP, ADP and AMP, was unchanged 4 h after the hepatectomy. Plasma amino acids did not differ significantly between hepatectomized and shunted control rats. On the other hand, clear‐cut increases in the concentrations of glutamine, and decreases in the concentrations of glutamate and aspartate, were observed in the fronto‐parietal part of the cerebral cortex and the brain stem. These changes might explain the minor manifestations of cerebral dysfunction in the early phase of the hepatectomized state.
A variant form of X‐linked chronic granulomatous disease with normal nitroblue tetrazolium slide test and cytochrome b
Authors: BORREGAARD NIELS , CROSS ANDREW R. , HERLIN TROELS , JONES OWEN T. G. , SEGAL ANTHONY W. , VALERIUS NIELS HENRIK
Published: March 2008

Abstract. Chronic granulomatous disease was diagnosed in a boy who suffered from severe generalized infections. Family investigations revealed the inheritance of the disease to be X‐linked. However, unlike other cases of X‐linked chronic granulomatous disease, the membrane oxidase of the neutrophils from this patient was not totally defective and sufficient activity was left to result in a normal phorbol myristate acetate‐stimulated nitroblue tetrazolium slide test. Also, unlike the usual findings in X‐linked chronic granulomatous disease, cytochrome b was present in normal amounts in the neutrophils from this patient. The cytochrome was normal, judged from its midpoint potential of —245 mV and its ability to bind CO. It is thus apparent that X‐linked chronic granulomatous disease may result from at least two different defects and that the phorbol myristate acetate stimulated nitroblue tetrazolium slide test fails to detect some cases.
Respiratory excretion of hydrogen and methane in Italian subjects after ingestion of lactose and milk
Authors: ZUCCATO ETTORE , ANDREOLETTI MARCO , BOZZANI ANGELO , MARCUCCI FRANCA , VELIO PIETRO , BIANCHI PAOLO , MUSSINI EMILIO
Published: March 2008

Abstract. Lactose malabsorption, by the breath hydrogen test, and lactose intolerance (presence of symptoms) were studied in twenty healthy Italian subjects after intake of 12.5, 25 and 50 g lactose, whole milk and low‐lactose milk. A rise in respiratory concentration of hydrogen (>20 ppm) (malabsorption) was found in fifteen subjects after 50 g lactose, in thirteen after 25 g and in seven after 12.5 g. Symptoms generally occurred in subjects presenting a rise in respiratory hydrogen excretion, but such a rise was often observed without symptoms. Thirteen subjects presented symptoms after 50 g lactose, but only three after 25 g and one after 12.5 g. Whole milk (500 ml) gave a lower incidence of lactose malabsorption than 25 g lactose (7/20 versus 13/20, P < 0.05) and more subjects developed symptoms (7/20 versus 3/20, NS). Low‐lactose milk produced no malabsorbers and one intolerant. Breath methane was detected constantly in seven subjects and in three on some of the days of observation. Respiratory methane excretion generally appeared to be unrelated to lactose ingestion.
Decreased serum concentration of ionized calcium in insulin‐dependent human diabetes mellitus
Authors: McNAIR P. , FOGH‐ANDERSEN N. , MADSBAD S. , CHRISTENSEN M. S.
Published: March 2008

Abstract. Low serum ionized calcium concentrations were observed in twenty‐five insulin dependent diabetic outpatients compared with twenty‐three age‐matched normal subjects: mean 1.16 mmol/l (SEM 0.01) versus 1.20 mmol/l (0.01), P < 0.002. Despite this, there was no compensatory increase in serum concentrations of immunoreactive parathyroid hormone, nor was serum total calcium decreased in the diabetic patients. Serum magnesium was significantly decreased in the diabetics compared with normals: mean 0.75 mmol/l versus 0.83 mmol/l, P < 0.001. No significant correlation could be demonstrated between serum magnesium and serum ionized calcium or parathyroid hormone in the diabetic patients.

Since no significant correlations were observable between serum ionized calcium and indices of diabetes control, the etiology and pathogenesis of decreased serum calcium ion in insulin‐dependent human diabetes mellitus remain unknown.
Protoporphyrinogen oxidase and ferrochelatase in porphyria variegata
Authors: VILJOEN D. J. , CUMMINS R. , ALEXOPOULOS J. , KRAMER S.
Published: March 2008

Abstract. Protoporphyrinogen oxidase activity and ferrochelatase activity were measured in leucocytes from patients with porphyria variegata. The mean activity of protoporphyrinogen oxidase (PPO) in porphyria variegata (PV) was about 50% of normal (P < 0.05). The mean activity of ferrochelatase with 59Fe2+ sulphate and protoporphyrin as substrates (in the presence of ascorbic acid) was reduced by 40% (P < 0.009). The mean activity of ferrochelatase with 59Fe3+ chloride and protoporphyrin as substrates (in the presence of reduced glutathione) was increased by 65% (P < 0.005). Both are statistically highly significant. The findings are interpreted as follows: (a) The occurrence of a low level of protoporphyrinogen oxidase in PV is confirmed, (b) The findings indicate a concurrent structural change in ferrochelatase (this may be structurally related to (a) but no evidence of this is at present available).
Diurnal changes in serum triglycerides as related to changes in lipolytic enzymes, (apo) lipoproteins and hormones in normal subjects on a carbohydrate‐rich diet
Authors: MIRANI‐OOSTDIJK C. PAGANO , HAVEKES L. , TERPSTRA J. , FRÖLICH M. , GENT C. M. VAN , JANSEN H.
Published: March 2008

Abstract. Normal subjects in steady state on a carbohydrate‐rich diet (three equivalent meals a day at 9.00, 13.00 and 17.00 h), show a wave‐like serum triglyceride (TG) pattern with a peak at 14.00 h. Post‐heparin lipoprotein lipase (LPL) activity increased from a mean value of 49 mU/ml ± 13 (SD) in the fasting state to 127 mU/ml ± 18 in the fed state (P < 0±005). This was due to an increase in adipose tissue LPL activity which, at 16.30 and 21.30 h, was significantly higher than basal levels (12.3 ± 81.5 and 87.7 ± 23.2 v. 43.3 ± 9.3 mU/g, P < 005 and P < 001, respectively). Skeletal muscle LPL activity was low (5.8 mU/g ± 2.3, mean ± SD) and showed no diurnal change. The observed changes in TG‐hydrolysing capacity in the course of the day might explain the TG‐pattern.

High density lipoprotein (HDL) subfractions HDL2 and HDL3 were separated by density gradient ultra‐centrifugation and had mean hydrated densities of 1088 and 1135 g/ml, respectively. While HDL2 showed no diurnal change, HDL3‐cholesterol and ‐phospholipid significantly increased during the day (P < 0.005 and P < 0.001 respectively), reaching their highest levels in the evening. Since the rise in HDL3‐lipids follows the fall in serum TG, this provides further indication that the metabolism of these fractions is mutually related.
Abnormal Na+K+ cotransport function in a group of patients with essential hypertension
Authors: GARAY R. P. , NAZARET C. , HANNAERT P. , PRICE M.
Published: March 2008

Abstract. In 50 normotensive controls, the increase in erythrocyte Na+ concentration up to 12.4 ± 2.0 mmol/l cells (mean ± SD) ensures half‐maximal stimulation of outward Na+K+ cotransport fluxes. Forty‐six out of sixty‐five patients with essential hypertension required more than 16 mmol/l cells of internal Na+ concentration to obtain a similar effect, strongly suggesting an abnormal cotransport function.

Seven out of fourteen hypertensive patients with normal Na, K cotransport function showed Na+Li+ countertransport fluxes higher than the normal upper limit of 220 μmol (1 cells h)‐1. Conversely, counter‐transport fluxes were normal in fourteen hypertensives with abnormal cotransport function.

The above results indicate that the total population of patients with essential hypertension is heterogenous and includes one subgroup of subjects with abnormal Na+K+ cotransport function, and another with increased Na+Li+ countertransport fluxes.
Vasoactive intestinal polypeptide (VIP) increases vaginal blood flow and inhibits uterine smooth muscle activity in women
Authors: OTTESEN BENT , GERSTENBERG THOMAS , ULRICHSEN HELLE , MANTHORPE TOVE , FAHRENKRUG JAN , WAGNER GORM
Published: March 2008

Abstract. The human vagina and uterus are heavily innervated by VIP‐containing nerve fibres. In the present study, we have measured vaginal blood flow, transmucosal oxygen tension and uterine smooth muscle activity during stepwise intravenous infusion of vasoactive intestinal polypeptide (VIP) (0, 100, 300, 900 pmol kg‐1 h‐1) in non‐pregnant women. Vaginal blood flow was measured by the heat clearance technique, transmucosal oxygen tension by an O2‐electrode and uterine activity by a micro‐tip pressure catheter in the uterine cavity. Arterial blood pressure, pulse frequency and the concentration of VIP in peripheral venous blood were monitored. VIP induced a concentration‐dependent increase in vaginal blood flow. The transmucosal oxygen tension was not significantly changed by VIP. The maximum dose of VIP decreased systolic as well as diastolic blood pressure and increased pulse frequency. VIP inhibited uterine activity. These findings suggest that VIP participates as a neurotransmitter in the control of genital physiological responses.
Differences in β‐adrenergic receptor density and adenylate cyclase activity between normal and leukaemic leukocytes
Authors: PAIETTA ELISABETH , SCHWARZMEIER JOSEF D.
Published: March 2008

Abstract. An identical class of high‐affinity binding sites for the 125I‐labelled β‐adrenergic antagonist hydroxybenzylpindolol, was identified on intact human normal and leukaemic peripheral blood leukocytes. On normal unfractionated lymphocytes, polymorphonuclear leukocytes, and monocytes, receptor density did not differ significantly (1200–1400 receptors per cell; P > 0.3), but it was higher on B‐ than on T‐lymphocytes (P < 005). In leukaemia, monocytic blast cells expressed highest receptor numbers, whereas very low receptor density was seen on the pathologic B‐cells from chronic lymphocytic leukaemia. Among normal leukocytes, adenylate cyclase activation by hormones (isoproterenol, prostaglandin E1, histamine) and sodium fluoride was strongest in plasma membranes from monocytes, but very weak in polymorphonuclear leukocytes either due to uncoupling of hormone receptors from adenylate cyclase or to low catalytic activity. In T‐cells, enzyme activity was significantly lower than in B‐cells. Loss of adenylate cyclase sensitivity to hormones and fluoride occurred in leukaemic cells from chronic and acute lymphocytic leukaemia.
Fibrinolytic activity of the gastric mucosa in Ménétrièr's disease
Authors: WIJNGAARDS G. , JESPERSEN J.
Published: March 2008

Abstract. Biopsies of the gastric mucosa were collected from two patients with Menetrier's disease before, during, and after treatment with cimetidine and studied for fibrinolytic activity. The fibrinolytic activity in the homogenates or in the potassium thiocyanate soluble fractions increased markedly during the treatment. Immunological characterization of the activity indicated that its major component was an endothelium‐derived type of plasminogen activator, and that the increase in activity was caused solely by an increase in the concentration of this component. This suggests an increase in the vascularity of the mucosal layers during treatment thus reflecting a repair process.
Effect of carbenoxolone on gastric prostaglandin E2 levels in patients with peptic ulcer disease following vagal and pentagastrin stimulation
Authors: RASK‐MADSEN J. , BUKHAVE K. , MADSEN P. E. R. , BEKKER C.
Published: March 2008

Abstract. The influence of oral carbenoxolone sodium (50 mg × 3 daily) on prostaglandin E2 release into gastric juice has been examined in nine peptic ulcer patients (duodenal ulcer, n= 6; prepyloric ulcer, n= 1; gastric ulcer, n= 2) during modified sham feeding and following bolus stimulation of acid secretion by pentagastrin (6 μg/kg).

Carbenoxolone increased the overall mean of prostaglandin E2 concentrations in gastric juice following modified sham feeding by 32 ± 9% (mean + SEM; P < 0.02) and decreased the acidity slightly but significantly (P < 0.05). A marked rise in prostaglandin E2 levels (46 ± 11%; n= 5; P < 0.02) was observed in four duodenal ulcer patients and the patient with a prepyloric ulcer responding to therapy (i.e., pain relief and ulcer healing within 4 weeks of treatment).

A significant peak (P < 0.05) related to modified sham feeding was observed only during medication, while a late gradual increase in prostaglandin E2 levels—not associated with vagal stimulation—occurred both in control and carbenoxolone experiments. No significant differences were observed following pentagastrin stimulation.

The initial peak in prostaglandin E2 levels observed during medication favours the notion that the mechanism of drug action relies on inhibition of enzymatic degradation while the late increase in prostaglandin E2 levels may be explained by artificial prostaglandin formation during the aspiration procedure.
Biochemical characterization of variants of the Ehlers‐Danlos syndrome type VI
Authors: IHME ANNEGRET , RISTELI LEILA , KRIEG THOMAS , RISTELL JUHA , FELDMANN URSULA , KRUSE KLAUS , MÜLLER PETER K.
Published: March 2008

Abstract. Three variants of the Ehlers‐Danlos syndrome type VI are described: a severe form with skeletal, dermal and ocular manifestations associated with a lack of hydroxylysine in skin and little lysyl hydroxylase activity in cultured fibroblasts; a similarly affected form with a nearly normal hydroxylsine content in skin, but with only little enzyme activity in cultured fibroblasts; and a predominantly ocular form with no biochemical abnormality in skin or cultured skin fibroblasts. The activities of prolyl 4‐hydroxylase and the two hydroxylysyl glycosyltransferases were normal in all cases, and the failure to find lysyl hydroxylase activity was not due to altered solubility characteristics of the enzyme or to the presence of an enzyme inhibitor. The collagen produced in cell culture, however, was hydroxylated to a markedly higher extent than that found in skin. In both the mutant and control cells hydroxylation of lysyl residues was less sensitive to ascorbate deficiency than that of prolyl residues.
Calcium malabsorption in the elderly: the effect of treatment with oral 25‐hydroxyvitamin D3
Authors: FRANCIS R. M. , PEACOCK M. , STORER J. H. , DAVIES A. E. J. , BROWN W. B. , NORDIN B. E. C.
Published: March 2008

Abstract. Calcium malabsorption is common in the elderly and may contribute to the development of age‐related bone loss. To investigate its cause, we have measured radio‐calcium absorption, plasma 25‐hydroxyvitamin D, 1,25‐dihydroxyvitamin D and parathyroid hormone in forty‐eight elderly women with a normal plasma creatinine. Calcium malabsorption was associated with low 25‐hydroxyvitamin D concentrations and was corrected by increasing these into the normal range by treatment with oral 25‐hydroxyvitamin D3. Treatment also increased 1,25‐dihydroxyvitamin D, and decreased parathyroid hormone concentrations.

Before treatment, plasma parathyroid hormone was related to plasma creatinine but not to 25‐hydroxyvitamin D, and the change in absorption on treatment correlated inversely with plasma creatinine. 51Cr EDTA clearance was measured in sixteen elderly women and confirmed that renal impairment was common even with a plasma creatinine in the normal range. Our results suggest that calcium malabsorption in the elderly is predominantly due to vitamin D deficiency; renal impairment is also common and contributes to the malabsorption by increasing the requirements for vitamin D.
L‐norgestrel and progesterone have different influences on plasma lipoproteins
Authors: FÅHRAEUS LARS , LARSSON‐COHN ULF , WALLENTIN LARS
Published: March 2008

Abstract. Twenty‐six postmenopausal women wh had been on cutaneous oestradiol treatment for 3–6 months were given either 120 μg of l‐norgestrel (n= 13) or 300 mg of progesterone (n= 13) sequentially fc another 6 months. The concentrations of cholestero phospholipids and triglycerides were determined i plasma and in the HDL, HDL2, HDL3, LDL an VLDL fractions before and after one, three and si cycles of progestin treatment.

Already after 11 days on l‐norgestrel, the mea HDL cholesterol and the mean HDL phospholipi concentrations were reduced by 15%. The reduction c the HDL‐lipids was mainly confined to the HDL fraction which was decreased by 25–30%. L‐norgestn also reduced the mean TG concentration both in the VLDL and the combined LDL + HDL fraction Progesterone gave only minor changes of the plasm lipids and lipoproteins.

Reduced HDL, especially HDL2, concentration, a induced by l‐norgestrel, might increase the risk fc ischaemic heart disease. Therefore, it seems that, a regards the effects on the lipoproteins, progesteron might be more suitable than the 19‐nortestosteron derivated l‐norgestrel for postmenopausal sequenti; hormonal therapy.
Erythrocyte uroporphyrinogen‐I‐synthase activity in β‐thalassaemic patients
Authors: LYBERATOS C. , LADAS S. , LADAS I. , PALIKARIS G. , LAZANAS M. , KOUTSIKOS S.
Published: March 2008

Abstract. The haem pathway enzyme uroporphyrino‐gen‐I‐synthase (UPGS) was assayed in erythrocyte samples from twenty normal, twenty β‐thalassaemia heterozygotic and twenty jS‐thalassaemia homozygotic subjects, after partial separation of the erythrocytes according to their age. UPGS erythrocyte enzyme concentration activity was significantly higher in the young than in the old erythrocytes of normal (66·5 ± 11·8 v. 45 ± 9·5 nmol h‐1 I‐1, mean ± SD, P < 0·001) and β‐thalassaemia heterozygotic subjects (70·1 ± 18·7 v. 49·8 ± 14·5 nmol h‐1 I‐1, P lt; 0·001), but not in patients with homozygous β‐thalassaemia (46·0 ± 12·8 v. 44·1 ± 12·5 nmol h‐1 I‐1, P= 0·65). Furthermore, UPGS enzyme concentration of both young and old erythrocytes of homozygous β‐thalassaemia was significantly lower than that of the young (P < 0·001) but similar to that of the old (P > 0·2) erythrocytes of either normal or β‐thalassaemia heterozygotic subjects. Since severe chronic haemolysis due to haemoglobinopathies is associated with increased UPGS enzyme concentration, these results suggest that UPGS activity may be suppressed in homozygous β‐thalassaemia.
Ultrasonic tissue characterisation of skeletal muscle
Authors: CADY E. B. , GARDENER J. E. , EDWARDS R. H. T.
Published: March 2008

Abstract. Ultrasound techniques have been used for the non‐invasive, quantitative characterisation of muscle tissue in normal subjects and volunteer patients. Radio frequency (RF) echoes from a volume of tissue have been digitised and analysed using computer techniques.

Attention has been given to the correct positioning and orientation of the transducer during examination due to the importance of the angle dependence of the interaction of ultrasound with muscle fasciculi. Several different muscles in the leg, arm and back of normal subjects have been examined, whereas patient studies have concentrated on the vastus intermedius. Ultrasonic data from patients with muscular dystrophy have been correlated with measurements of muscle tissue density obtained using X‐ray computerised tomography (X‐ray CT). The technique shows that ultrasound can be used to differentiate between normal and diseased muscle quantitatively. Results indicate that pathological change can be detected and monitored earlier with ultrasound than with X‐ray CT.

These quantitative methods are now in use as a guide to the staging and monitoring of pathological change in muscle.
Lack of inhibition of clomethiazole metabolism by cimetidine: model experiments in the dog
Authors: ZENG J. Z. , BIRCHER J.
Published: March 2008

Abstract. The disposition of clomethiazole was studied in six dogs subjected to pretreatment with cimetidine or saline according to a cross‐over design. Pretreated dogs received approximately 20 mg/kg of cimetidine p.o. for 4 days and 30 mg/kg i.v. immediately before an intraduodenal infusion of clomethiazole (117/μol/kg clomethiazole base within 90 min). Compared to controls, cimetidine had no effect on peak plasma concentrations and on areas under the plasma concentration time curves of clomethiazole or of its metabolite 5‐acetyl‐4‐methylthiazole (P > 0·05). Identical pretreatment of the same dogs resulted in a 50% inhibition of aminopyrine demethylation (P < 0·001) as revealed by the aminopyrine breath test. Clomethiazole may be metabolized in the dog through metabolic routes which cannot be inhibited by cimetidine.
Regulation of calcium‐regulating hormones by exogenous sex steroids in early postmenopause
Authors: STEVENSON JOHN C. , ABEYASEKERA GAMINI , HILLYARD CARMEL J. , PHANG KHENG‐GUEK , MacINTYRE IAIN , CAMPBELL STUART , LANE GEOFF , TOWNSEND PETER T. , YOUNG OSYTH , WHITEHEAD MALCOLM I.
Published: March 2008

Abstract. A major function of calcitonin in humans appears to be maintenance of the skeleton. There is a marked sex difference in circulating calcitonin levels: women have much lower levels. This has led to speculation that calcitonin lack may be one factor involved in the pathogenesis of postmenopausal bone loss.

We have measured levels of calcitonin and the other major calcium‐regulating hormones in healthy women during the early menopause, and studied the effects of reversing their oestrogen deficiency with natural and synthetic oestrogen. The major findings were that calcitonin levels were increased by oestrogen administration (P<0·02‐<0·001) and that the levels of the bone‐resorbing hormones, parathyroid hormone and 1,25 dihydroxyvitamin D, were not higher in postmenopausal than in premenopausal women. We suggest that loss of oestrogen at the menopause accelerates the natural age‐related decline of calcitonin secretion, thus further decreasing the calcitonin levels. This leads to increased sensitivity of the skeleton to the actions of the bone‐resorbing hormones.

It seems likely that the well‐known effect of oestrogen in preventing postmenopausal bone loss is achieved, at least in part, by enhancement of calcitonin secretion.
Heterogeneity of alveolar surfactant in the rabbit: composition, morphology, and labelling of subfractions isolated by centrifugation of lung lavage
Authors: BARITUSSIO A. , BELLINA L. , CARRARO R. , ROSSI A. , ENZI G. , MAGOON M. W. , MUSSINI I.
Published: March 2008

Abstract. Rabbit alveolar saturated phosphatidylcholine (SPC) can be separated by differential and density gradient centrifugation of lung lavage into three fractions. One fraction (‘B’), which is analogous to conventionally prepared alveolar surfactant, contains 46·0±5·9% (SD) of lavage SPC, and is made of large multilamellar vesicles or sheet‐like structures. A second fraction (‘C’) does not sediment after centrifugation at 80000g for 90 min, contains 29·8±14·0% of lavage SPC, and a uniform population of small vesicles. This fraction incorporates 3H‐palmitate administered intravenously with a small delay with respect to fraction ‘B’. A third fraction (‘D’) contains almost all the cells of lavage and less than 5% of lavage SPC.

We conclude that alveolar SPC consists of more than one compartment. The possible significance of isolated fractions is discussed.
Haemodynamic effects of prenaterol and cardiac glycosides in patients with recent myocardial infarction
Authors: BOSTRÖM P.‐Å. , ANDERSSON J. , JOHANSSON B. W. , LILJA B. , THORELL J. , TIDFÄLT K. , WESTERLING S.
Published: March 2008

Abstract. Prenalterol was given to twenty five patients with acute myocardial infarction. Thirteen patients (group B) had signs of cardiac decompensation while twelve (group A) had not. Ejection fraction was determined with 99mTc‐labelled red blood cells before and after prenalterol (50 μg kg‐1 body weight), intravenously. In group B this procedure was repeated after digitalization 2 days later. The ejection fraction increased significantly in group A after prenalterol injection. In group B, prenalterol produced an increase, but this was not significant. After digitalis the ejection fraction increased significantly and prenalterol produced an additional significant rise. No significant changes in blood pressure occurred. Heart rate increased significantly in both groups after prenalterol injection and decreased significantly after digitalis.
Rapid proteolysis of puromycyl peptides in non‐thalassaemic and thalassaemic erythroid cells
Authors: CHALEVELAKIS GEORGE , LYBERATOS COSMAS , YALOURIS ATHANASIOS , VAIDAKIS EMMANUEL , PALLIKARIS GEORGE , RAPTIS SOTIRIOS
Published: March 2008

Abstract. The proteolytic degradation of labelled pyromycyl polypeptides was investigated in human intact erythroid cells derived from the bone marrow of eight non‐thalassaemic patients and the peripheral blood of eleven thalassaemics (eight splenectomized β thalassaemia heterozygotes and three sickle‐cell β thalassaemics). These abnormal polypeptides are rapidly degraded to soluble trichloroacetic‐acid (TCA) fragments with a half‐life of 12 min both in bone marrow and peripheral blood. This comes very close to the half‐life reported for the puromycyl peptide degradative system in rabbit reticulocytes (15 min).

The relationship of the present proteolytic system to the ATP‐dependent one, described in rabbit reticulocytes, and to that responsible for the free α‐chain degradation in α thalassaemia is discussed.
Abnormal processing of antral gastrin in active duodenal ulcer disease
Authors: PETERSEN BIRTE , ANDERSEN BENT NYBOE
Published: March 2008

Abstract. The concentrations of gastrins containing the active C‐terminal tetrapeptide amide (mainly gastrin‐34 and gastrin‐17) and the N‐terminal tridecapeptide fragment of gastrin‐17 were measured in antral and duodenal biopsy specimens. The antral concentration of the N‐terminal gastrin fragment was much higher in patients with active duodenal ulcer (33·4 ± 6·8 nmol g‐1, mean ± SEM, n= 15) than in controls (5·6 ± 2·9 nmol g‐1, n= 10), patients with gastric ulcer (5·6 ± 1·8 nmol g‐1, n= 10) or patients with pernicious anaemia (7·7 ± 2·5 nmol g‐1, n= 6). No differences were found between the groups regarding gastrin‐34 and gastrin‐17 concentrations. In duodenal extracts, the N‐ and C‐terminal gastrin concentrations were similar in all groups of patients. These data suggest that the posttranslational processing of antral gastrin is abnormal in patients with active duodenal ulcer disease.
Serum lipids, lipoproteins and apolipoprotein E phenotypes in relatives of patients with type III hyperlipoproteinaemia
Authors: STUYT P. M. J. , DEMACKER P. N. M. , LAAR A. VAN ‘T
Published: March 2008

Abstract. Eighty‐six relatives of nineteen probands with type III hyperlipoproteinaemia were studied to determine the occurrence of hyperlipidaemia and to investigate the relation between apo E phenotypes, the occurrence of hyperlipidaemia, and the composition of the very low density lipoprotein (VLDL) fraction. Thirty‐nine relatives were hyperlipidaemic: four type IIa or IIb, nine type III and twenty‐six type IV. The predisposition for hyperlipidaemia was independent of the apo E phenotype.

Hyperlipidaemic relatives with apo E phenotype E2/2 had a significantly (P < 0·01) higher VLDL‐cholesterol/VLDL‐triglycerides ratio (1·26 ± 0·35 n= 9) than those heterozygous for apo E allele ɛ2 (0·66 ± 0·12, n= 23) or without apo E allele ɛ2 (0·69 ± 0·11, n= 7). Normolipidaemic homozygous apo E‐2 relatives had also a significantly (P < 0·05) higher ratio (0.97 ± 0·19, n= 6) than those heterozygous for (0·77 ± 0·19, n= 31) or without the apo E allele ɛ2 (0·74 ± 0·13, n= 10). Thus, both hyper‐ and normolipidaemic apo E2 homozygotes have higher concentrations of VLDL remnants than the subjects heterozygous or without allele ɛ2.
Nephrogenous cyclic AMP and plasma parathyroid hormone in hypercalcaemia: the influence of renal function
Authors: BILL GERARD , JACQUET ANNE‐FRANÇOISE , BURCKHARDT PETER
Published: March 2008

Abstract. Immunoreactive parathyroid hormone (PTH) levels and nephrogenous cyclic adenosine monophosphate (cAMP) have been reported to be useful parameters in the diagnosis of hyperparathyroidism. Measurements in hyperparathyroid patients usually give values above the normal range when PTH is measured with a carboxyterminal radioimmunoassay and when nephrogenous cAMP is related to glomerular filtration rate. We tested these two parameters in two groups of hypercalcaemic patients (twelve cases of primary hyperparathyroidism and fourteen cases of hypercalcaemia of non‐parathyroid origin) and in two groups of normocalcaemic subjects (twenty‐one young healthy volunteers and fourteen elderly subjects without parathyroid disease). Slight impairment of renal function caused elevated values of immunoreactive parathyroid hormone in a carboxyterminal radioimmunoassay and also of nephrogenous cAMP when related to glomerular nitration rate. We found that elevated nephrogenous cAMP without parathyroid disease could be attributed to renal insufficiency and to the mode of expression generally used for the nephrogenous cAMP.
Effects of ethanol and acetaldehyde on cultured rabbit aortic myocytes and human platelets in vitro
Authors: STAVENOW L. , JERNTORP P. , ÖHLIN H.
Published: March 2008

Abstract. The recently reported finding that a moderate alcohol consumption may lower the risk of cardiovascular disease prompted a study of the effects of ethanol and acetaldehyde on proliferation, viability and collagen secretion of rabbit aortic myocytes in culture and on the spontaneous efflux reaction of human platelets in vitro. Ethanol had no effects on any of the systems and acetaldehyde did not influence platelets significantly. Fifty μmol l‐1 acetaldehyde diminished the proliferation and collagen secretion of arterial myocytes by 20% (P < 0·01) and 100 μmol l‐1 acetaldehyde by 39% (P < 0·001) without affecting cell mass or cell death. A metabolic degradation, and some evaporation, of acetaldehyde was taking place and 50 μmol l‐1 acetaldehyde was halved after approximately 2 h. The more ‘physiological’ concentration of acetaldehyde (5 μmol l‐1) influenced cell proliferation significantly (P < 0·001) if the concentration was restored by 6‐h intervals and the incubation time increased from 24 to 48 h. The weak aldehydedehydrogenase inhibitor chlorpropamide did not accentuate the effects of acetaldehyde.
Impaired plasma amino‐acid clearance in patients with cirrhosis of the liver and portocaval shunt—its relation to insulin resistance
Authors: FERENCI PETER , BRATUSCH‐MARRAIN PAUL , WALDHÄUSL WERNER K. , NOWOTNY PETER , KORN ADRIENNE
Published: March 2008

Abstract. To study the interdependence of utilization of branched chain amino acids and glucose and of hyperinsulinaemia in patients with liver cirrhosis the plasma disappearance of glucose and amino acids was estimated in seven patients with cirrhosis and portocaval shunt and in seven healthy controls following infusion of glucose and essential amino acids during suppression of endogenous hormone release by somatostatin. Exogenous insulin was infused by means of an automated glucose controlled insulin infusion system. The data demonstrate that (i) insulin requirement almost doubled in patients as compared to controls to obtain similar blood glucose responses to i.v. glucose, and (ii) the plasma disappearance rates of the infused amino acids were reduced in the patients as compared to controls despite hyperinsulinaemia sufficient to achieve normal glucose assimilation. Thus, in cirrhotic patients insulin resistance may be overcome by excess insulin as far as glucose homeostasis is concerned, whereas amino‐acid metabolism still remains impaired.
Progressive renovascular hypertension by increasing aortic constriction in rats
Authors: MARTÍN‐PAREDERO VICENTE , CASADO SANTOS , LÓPEZ‐NOVOA JOSÉ M.
Published: March 2008

Abstract. Moderate and progressive hypertension was produced experimentally in rats by progressive aortic constriction. The progression of the stenosis was assessed by the differences of pressure across the stenosis. Haemodynamic studies were performed 15, 30 and 60 days after the ligature was placed or after sham operation. Fifteen days after surgery, when the ligated rats did not show any increase in carotic pressure, they showed augmented cardiac output (50·3pL5·4 v. 29·7 pL 2·0 ml min‐1 100 g‐1; mean pL‐SEM) and a decreased total peripheral resistance (2·23pL0·21 v. 3·67 pL 0·20 mmHg ml‐1 min 100 g). They also had decreased vascular resistance in both kidneys and in skeletal muscle samples above and below the ligature as well as increased plasma renin content and normal values of plasma volume and extracellular volume. Later in the evolution of hypertension, carotic pressure and the pressure gradient across the stenosis increased (51·8 pL 4·5 v. 0·9 pL 1·6 mmHg in controls), cardiac output decreased to control values, total peripheral resistance as well as renal and muscular vascular resistances increased. Plasma and extracellular volume remained unchanged in ligated rats in contrast to controls where they decreased. Perfusion pressure of the kidney below the ligature did never fall below control values (97·2 pL 3·4 v. 100·4 pL 2·4 mmHg). A small but constant degree of elastosis and a double layer of myocytes in the renal arterioles above the ligature was the only histological finding.