bluuebunny/crossref_metadata_2025_split huggingface dataset:
Relationship of brain glutamine and brain neutral amino acid concentrations after portacaval anastomosis in rats
Authors: JEPPSSON B. , JAMES J. HOWARD , EDWARDS LAURA L. , FISCHER J. E. 
Published: March 2008

Abstract. Evidence from several sources suggest that blood‐brain transport of the large neutral amino acids (NAA) is abnormal in animals with a portacaval anastomosis (PCA) and in patients with liver cirrhosis and portal‐systemic shunting and encephalopathy, but the underlying mechanisms are unknown. After PCA, the concentration of glutamine (Gin) in brain is markedly increased as a by‐product of cerebral ammonia detoxification, and the rate of efflux of Gin from brain is also increased. The following studies were undertaken to clarify the relationships among plasma and brain concentrations of NAA after PCA in rats and to examine the relationship of brain Gin concentration to plasma and brain NAA concentrations.After PCA plasma phenylalanine, tyrosine and histidine were elevated and leucine, isoleucine and valine were lowered. In brain, phenylalanine, tyrosine, histidine and methionine were markedly elevated after PCA and their concentrations in brain far exceeded the concentrations in plasma.Analyses of single, partial and multiple correlations of plasma NAA ratios expressed as plasma competitor function (PCF), brain NAA and brain Gin showed significant correlations between PCF and brain NAA in shunted rats. A better correlation was found between brain NAA and brain Gin.Correlation coefficients obtained from multiple correlation analysis equalled or exceeded those obtained in the partial correlation or in the single correlation, suggesting that the effects of PCF and brain Gin on brain NAA were separate and additive. Gin was shown to compete with other NAA for blood brain transport by inhibiting brain 14C phenylalanine uptake. This in combination with the relationship demonstrated between brain Gin concentration and brain NAA concentrations suggests that Gin exerts some effect on blood‐brain NAA transport. This has therapeutic implications in patients with liver failure and encephalopathy.
Metabolic response to different forms of physical exercise in type I diabetics and the duration of the glucose lowering effect
Authors: HÜBINGER A. , RIDDERSKAMP I. , LEHMANN E. , GRIES F. ARNOLD 
Published: March 2008

Abstract. In order to analyse the metabolic effects of exercise nine well‐controlled type I diabetics took part in four series of tests: (i) a short exercise with maximal work load, (ii) a 30 min exercise with half maximal work load, (iii) a 3 × 10 min interval exercise and (iv) control without exercise. Exercises were performed on a bicycle ergometer starting at 09.00 h. On the test days, only two thirds of the normal insulin dose was given.Blood glucose, free insulin, glucagon, catecholamines, growth hormone, Cortisol, lactate and pyruvate were measured during the exercise and the following 60 min. Glucose profiles were taken until 17.15 h.The short exercise with maximal work load did not affect blood glucose, the half maximal exercise and the interval exercise resulted in a decrease. Short rest phases did not modify the glucose lowering effect nor the overall response of counterregulatory hormones. A snack following exercise resulted in a total compensation of the glucose lowering effect.
Antibodies to human T‐cell lymphotropic virus type III in promiscuous healthy homosexual men. Relation to immunological and clinical findings
Authors: GERSTOFT J. , LINDHARDT B. ØRSKOV , PETERSEN C. S. , KROON S. , ULLMAN S. , MØLLER S. , NIELSEN J. OLE , DICKMEISS E. 
Published: March 2008

Abstract. Antibodies to human T‐cell lymphotropic virus type III (HTLV‐III Ab) were present in twenty‐one out of sixty‐four asymptomatic promiscuous homosexual men from Copenhagen. The presence of HTLV‐III Ab was associated with lymphadenopathy (P<0·0005), cytomegalovirus isolation (P<0·01), low skin test reactivity (P<0·01) and episodes of fever within the 2 month period prior to investigation (P<0·05). No significant differences occurred in the total number of T‐cells, T‐suppressor cytotoxic cells, T‐helper cells or helper to suppressor ratio (H/S ratio) between HTLV‐III Ab positive and negative homosexuals. An H/S ratio ≤1·0 was significantly more frequent in homosexual men who both had HTLV‐III Ab and excreted cytomegalovirus (P<0·01).The H/S ratio of HTLV‐III negative homosexuals were significantly lower than that of the controls suggesting that a non‐HTLV‐III related immunosuppression occurs among homosexuals. Within 2 years after the investigation AIDS or the AIDS related complex developed in three of the men, who at the first investigation all had HTLV‐III Ab, alterations in T‐lymphocyte subsets and cutaneous anergy. It is suggested that a combination of T‐cell subset determination and determination of HTLV‐III Ab may provide more valuable prognostic information than isolated determintion of HTLV‐III Ab.
Neutral steroid metabolites in patients with uraemia and after renal transplantation: a quantitative and qualitative study in body fluids
Authors: LUDWIG‐KÖHN HELGA , HENNING H. V. , SZIEDAT ASTRID , KLUG P. , ALEXANDER H. , SCHELER F. 
Published: March 2008

Abstract. Steroid metabolites enriched from urine, haemofiltrate, and CAPD‐dialysate (Continous Ambulatory Peritoneal Dialysis) were identified by gas chromatography‐mass spectrometry and quantified by capillary gas chromatography. The study included twenty healthy controls, twenty‐six non‐dialysed urae‐mics, thirty‐nine patients on regular dialysis treatment, and twenty‐two allograft recipients.Compared to the 24 h urinary excretion rates of controls the excretion rates of androsterone and etiocholanolone were in the lower normal range up to significantly decreased in the body fluids of all patients, and those of the corticoid metabolites were also significantly decreased. 11‐Oxygenated androstano‐lones in urine from non‐dialysed uraemics correlated significantly decreased. 11‐oxygenated androstano‐levels and were significantly increased, but normal in haemofiltrate and CAPD‐dialysate, while in urine of allograft recipients the values were significantly lower.
Effect of captopril infusion on systemic and renal haemodynamics in conscious hypertensive rats with chronic, progressive aortic ligation
Authors: GONZALEZ‐PEREZ LUIS M. , MARTIN‐PAREDERO VICENTE , CASADO SANTOS , LOPEZ‐NOVOA JOSE M. 
Published: March 2008

Abstract. The effect of the converting enzyme inhibitor captopril (5 mg (kg bwt)‐1) on systemic and renal haemodynamics has been studied in conscious rats in which a progressive hypertension has been induced by progressive aortic ligation (AL) between the renal arteries, and in a sham‐operated (SO) group.Cardiac output (CO), organ blood flow and vascular resistances have been measured using radioactive microsphaeres.Captopril infusion caused increases in CO in both groups of rats, but the increase was higher in SO (9±2 ± 0±7%) than in AL rats (5±2 ± 0±6%; P<0±005). Plasma renin concentrations were similar in both groups but increased more in AL (10±3 μIU ± 1±0) than in SO (5±81 μIU ± 0±62; P<0±05) after captopril. Captopril induced also a larger decrease in arterial pressure (36 ± 4 mmHg), and of the pressure gradient across the stenosis (19 ± 3) mmHg in AL than in SO rats (5±6 ± 1±4 and 1±1 ± 1±3 mmHg, P < 0±005 for both cases). Vascular resistance of the kidney above the ligature decreased more in AL than in SO rats, but this difference was not observed in the other kidney.From these data it can be concluded that captopril has an acute hypotensive effect despite the normal renin levels of this model of chronic hypertension. In addition, blood flow to the high‐pressure perfused kidney seems to be dependent on the increased renin production by the contralateral kidney.
Maximal oxygen consumption and pulmonary circulation in patients with chronic bronchitis
Authors: HENRIQUEZ A. , SCHRIJEN F. , POINCELOT F. , GIMENEZ M. , POLU J. M. , SADOUL P. 
Published: March 2008

Abstract. In order to study the relations between maximal oxygen consumption during exercise (V̇O2max) and the pulmonary circulation when pulmonary artery pressure (PPA) and pulmonary vascular resistance (PVR) are normal or close to normal, we evaluated twenty‐three patients with chronic bronchitis, in stable clinical condition. All these patients performed a progressive exercise test on a bicycle ergometer until exhaustion (V̇O2max); they were also subjected to right heart catheterization at rest and during light exercise at constant load. In these patients with moderate functional impairment, we observed on average a significant, although weak, correlation (r=‐0·52, P<0·01) between pulmonary vascular resistance at rest and V̇O2max. When V̇O2max exceeded 2 l min‐1, PVR was below 210 dyn s cm‐5. From the heart rate during maximal exercise we computed the oxygen pulse (O2Pmax). In eight patients O2Pmax was reduced (≤ 11 ml) with maximal heart rate close to its predicted value; in seven of these subjects PVR was abnormal and P̄PA at rest was at least 20 mmHg.Thus it seems that in chronic obstructive bronchitis mild disturbances in pulmonary circulation may be a contributory factor in the limitation of exercise performance, and a maximal exercise test may help to detect pulmonary hypertension in these patients.
Biliary cholesterol saturation in non‐obese women and non‐obese men before and after puberty
Authors: BERGMANN K. VON , BECKER M. , LEISS O. 
Published: March 2008

Abstract. The lipid composition of gallbladder bile was determined in forty‐seven normal, non‐obese subjects (twenty females and twenty‐seven males) without gallstones ranging in age from seven months to twenty‐nine years. Before puberty, bile was undersaturated with cholesterol in both sexes to the same extent. After puberty a marked increase in cholesterol saturation was observed in females but not in males (138%vs 88%; P<0·01). A significant correlation between age and cholesterol saturation could be observed in females (r=0·546; P<0·05) but not in males.In addition a significant correlation between absolute weight and cholesterol saturation in all females (r=0·827; P<0·001) and those after puberty (r=0·659; P<0·05) could be demonstrated. In neither sex was saturation related to body mass index or ideal body weight. These findings suggest that saturation of bile raises in women during puberty but not in men, and this sex‐related difference in cholesterol saturation probably contributes to the more common occurrence of gallstones in women than in men.
Bisphosphonate whole body retention test: relations to bone mineralization rate, renal function and bone mineral content in osteoporosis and metabolic bone disorders
Authors: MOSEKILDE L. , HASLING C. , CHARLES P. , JENSEN F. TÅGEHØJ 
Published: March 2008

Abstract. The bisphosphonate whole body retention test (WBR) has been used to estimate bone mineralization rate (bone turnover). Bisphosphonates given i.v. are taken up by bone or excreted in urine. The aim of the present investigation was to test the efficacy of WBR in estimating bone mineralization rate (m) and to evaluate the influence of renal function (Clcr) and bone mass (forearm bone mineral content; BMC) on WBR. The 24‐h retention of 3–7 MBq 99mTc‐HMBP (1‐hydroxymethylene‐1,1 ‐bisphosphonate) (Osteoscan®) given i.v. was measured by a medium sensitive whole body counter in thirty‐one patients with hyperparathyroidisme (n= 14), hyperthyroidism (n= 8) or hypothyroidism (n= 9) (group 1) and in seventy‐six females with postmenopausal spinal crush fracture osteoporosis (group 2). In the same individuals m was calculated from a 7‐day 47Ca‐kinetic study using the expanding calcium pool model. Multiple regression analysis of WBR vs. m and Clcr in group 1 disclosed that WBR correlated positively to m [rp= 0·49, P<0·01 (rp= partial correlation coefficient)] and inversely to Clcr (rp=‐0·44, P<0·02). Inclusion of BMC in the analysis did not reveal any significant partial correlation between WBR and BMC (rp=‐0·33, 0·05 <P<0·10). In group 2 WBR correlated inversely to Clcr (rp= ‐0·48, P<0·001) but showed no significant relation to m (rp= 0·10, NS). WBR was not related to BMC (rp= 0·09, NS), WBR was slightly inferior to serum alkaline phosphatase and renal hydroxyproline excretion in estimating bone mineralization rate in group 1 and, contrary to the biochemical markers, inapplicable in group 2. A model was developed that took into account that bisphosphonate is either taken up by bone or excreted in the urine. The model, however, did not improve the efficacy by which m could be predicted from simultaneous measurements of WBR and Clcr, probably because of an increase in the method error.We conclude that measurements of the whole body retention of HMBP is of no value in estimation bone turnover in the investigated metabolic states characterized by wide variations in bone turnover and no mineralization defects.
Enhanced calcitonin secretion in the rat after parathyroidectomy and during chronic calcium deprivation
Authors: RAUE F. , WIELAND UTE , WEILER CHRISTINE , ZIEGLER R. 
Published: March 2008

Abstract. The thyroidal content of calcitonin (CT) and the serum calcitonin responses to acute hypercalcaemia were studied in female rats during chronic hypocalcaemia induced by parathyroidectomy (PTX), a low calcium (Ca) diet, or both. The thyroidal CT content of the PTX animals 50 days after surgery was twice that of intact rats. An acute intraperitoneal (i.p.) calcium load on day 50 after PTX resulted in an increase in serum CT twice as large as that observed in control animals. Reversal of the chronic hypocalcaemia with 1,25(OH)2D3 resulted in a reduction in thyroidal CT as well as a depression of the calcium‐induced CT response. In each case the values were similar to those observed in normocalcaemic controls. A low calcium diet increased the thyroidal CT content in intact rats and induced a further increase in PTX rats. The CT response to an acute Ca load was exaggerated by a low calcium diet in intact as well as in PTX rats.These results suggest that in the rat chronic hypocalcaemia enhances CT storage and secretion.
New form of dual porphyria: coexistent acute intermittent porphyria and porphyria cutanea tarda*
Authors: DOSS M. O. 
Published: March 2008

Abstract. A previously unrecognized form of dual porphyria has been identified in four patients. One male and one female with acute symptoms were diagnosed as having acute intermittent porphyria (AIP), and two males with cutaneous and acute symptoms were diagnosed as having porphyria cutanea tarda (PCT). Biochemically, the excretion of haem precursors showed a complex constellation, with signs characteristic of both AIP and PCT. In one male, a clinical course with both overt PCT and acute manifestations of AIP was observed. Enzyme studies of haem biosynthesis in erythrocytes revealed a dual deficiency, with decreased activity of both porphobilinogen deaminase, as seen in AIP, and uroporphyrinogen decarboxylase, as seen in PCT. A family study showed that the two disorders do not consistently segregate together.These findings suggest that the dual porphyria reflects a double heterozygous condition of coexistent AIP and PCT genes in the same subject.
Electromagnetically generated extracorporeal shock waves for gallstone lithotripsy: in vitro experiments and clinical relevance
Authors: STARITZ M. , RAMBOW A. , MILDENBERGER P. , GOEBEL M. , SCHERFE Th. , GROSSE A. , JUNGINGER Th. , HOHENFELLNER R. , THELEN M. , BÜSCHENFELDE K.‐H. MEYER ZUM 
Published: March 2008

Abstract. First generation shock wave sources have been proved to disintegrate gallstones effectively, but they require the immersion of the patient's body in a tank of water. A recently developed second generation shock wave source (Siemens‐Lithostar, Erlangen, FRG) generates shock waves electromagnetically. It presents several novel features. In particular the waterbath can be omitted and due to lower shock wave pressure general anaesthesia is not required. In vitro studies showed that 36 out of 38 gallstones (11–30 mm in diameter) could be disintegrated. Two concrements resisting lithotripsy were pure white cholesterol stones.Independent of shape, size, and composition (cholesterol or pigment) the maximum diameter of remaining fragments after lithotripsy was between 1 and 8 mm. For sufficient disintegration precise focusing (±1 cm) of the stones and maximum power of the shock wave generator were required.
Myocardial (iso)enzyme activities, DNA concentration and nuclear polyploidy in hearts of patients operated upon for congenital heart disease, and in normal and hypertrophic adult human hearts at autopsy
Authors: LAARSE A. VAN DER , HOLLAAR L. , VLIEGEN H. W. , EGAS J. M. , DIJKSHOORN N. J. , CORNELISSE C. J. , BOGERS A. J. J. C. , QUAEGEBEUR J. M. 
Published: March 2008

Abstract. To investigate biochemical characteristics of hypertrophic myocardium of young and adult humans, we analysed myocardial biopsies obtained from 28 mainly young patients undergoing cardiac surgery for congenital heart disease and 41 autopsied hearts from 18 adult normal and 23 hypertrophic human subjects. Myocardial activities of the enzymes creatine kinase and lactate dehydrogenase were independent of age during childhood, but decreased significantly with hypertrophy at adult age. Myocyte nuclei showed increased polyploidization during childhood which was progressive with age, and in the adult stage polyploidization was correlated with heart weight. Nevertheless myocardial DNA concentration fell under both conditions, which is to be ascribed to the ‘diluting’ effect of myocyte hypertrophy.Before an age of 8 years DNA concentration in the child heart material studied has reached the value found in adult nonhypertrophic hearts, although at that time polyploidization of myocyte nuclei in child hearts was only half the value found in adult nonhypertrophic hearts. Biochemical measurement of DNA concentration in peroperatively taken myocardial biopsies may contribute to the in vivo diagnosis of ventricular hypertrophy in quantitative terms, in combination with radiology, echocardiography and histology.
Effects of a bolus dose of atrial natriuretic factor in young and elderly volunteers
Authors: HEIM J.‐M. , GOTTMANN K. , WEIL J. , STROM T. M. , GERZER R. 
Published: March 2008

Abstract. We assessed the haemodynamic and renal effects as well as the effects on plasma cGMP levels of a small i.v. dose (33 μg) of human atrial natriuretic factor (99–126; hANF) in two age groups of healthy volunteers. Binding properties of platelet ANF receptors were also measured. The elderly (four males, eight females, mean age 52.3 years) showed increased haemodynamic (decrease in blood pressure) and renal responses (diuresis, natriuresis, calciuresis) as well as greater increases in plasma cGMP levels and urinary cGMP excretion than the young subjects (four males, 12 females, mean age 26 years). Binding capacities and affinities of platelet ANF receptors were identical in both groups.These data indicate that the sensitivity to ANF increases with age and that this increased sensitivity is reflected in the reactivity of plasma cGMP levels but not in the properties of platelet ANF receptors. The data may be important for the therapeutic use of ANF, for the understanding of the physiological regulation of ANF action and may underline the necessity of using age‐matched control subjects for clinical studies on the possible therapeutic effectiveness of ANF.
Metabolic effects of biosynthetic human proinsulin in type 2 diabetes mellitus
Authors: KLAUSER R. , PRAGER R. , WATSCHINGER B. , SCHERNTHANER G. 
Published: March 2008

Abstract. Due to a longer plasma half‐life and half‐time of action on glucose metabolism biosynthetic human proinsulin was thought to be an alternative to long‐acting insulin preparations. To test this hypothesis we studied 23 type 2 diabetic patients who could no longer be treated sufficiently with oral hypoglycaemic agents. After an initial 1 week phase during which all patients received protamine bound insulin twice daily, the patients either continued on NPH insulin (Group A, n= 11) or were randomly switched to human proinsulin (Group B, n= 12). Glucose profiles and peripheral and hepatic insulin sensitivity (euglycaemic clamp: 120 mU m‐2 min‐1) were measured at the end of the initial period (Time 1) and 1 week later (Time 2).The insulin‐mediated glucose disposal (RD) was not changed after either treatment (group A: 176±18 vs. 192±19 mg m‐2 min‐1; group B: 175 ± 15 vs.174±12 mg m‐2 min‐1 for times 1 and 2, respectively, NS). Suppression of hepatic glucose output (HGO) was complete in both groups at both times. Fasting blood glucose levels (FBG) and basal HGO were equally low at times 1 and 2 (group A: FBG 118 vs. 123 mg dl‐1, BHGO 81 vs. 79 mg m‐2 min‐1; group B: FBG 118 vs. 106 mg dl‐1, BHGO 87 vs. 84 mg m‐2 min‐1; NS). Mean blood glucose levels (MBG) were unchanged in the group receiving NPH insulin (164 vs. 162 mg dl‐1; NS) but improved in group B (182 vs. 142 mg dl‐1; P < 0.001). Blood glucose levels were lower in group B, expecially during the afternoon (from 12.00 to 19.00 h). Insulin requirement was the same in group A at times 1 and 2; in group B the proinsulin dosage was reduced significantly to 33 U day‐1 at time 2 as compared to an insulin dose of 41 U day‐1 at time 1 (P < 0.01). In summary, equal metabolic control can be achieved with proinsulin compared to protamine bound insulin with a lower dose on a unit base for proinsulin. Peripheral and hepatic insulin sensitivity remain unchanged during proinsulin therapy compared to NPH insulin treatment.
Reduction of lymphocytic β‐adrenoceptor level in chronic alcoholics and rapid reversal after ethanol withdrawal
Authors: MÄKI T. , HEIKKONEN E. , HÄRKÖNEN T. , KONTULA K. , HÄRKÖNEN M. , YLIKAHRI R. 
Published: March 2008

Abstract. Plasma catecholamine levels, lymphocytic β‐adrenoceptor densities and lymphocytic cAMP production were studied in 10 male subjects attending a withdrawal clinic after prolonged alcohol abuse. On admission the mean β‐adrenoceptor density was 29 ± 9 fmol mg‐1 protein (about 60% of the mean level of healthy control subjects, P < 0.002). The following day a significant elevation of the β‐adrenoceptor level up to 46±19 fmol mg‐1 protein (P<0.05) took place. This was accompanied by a parallel activation of the β‐adrenoceptor‐mediated cAMP production of the lymphocytes. No major changes in β‐adrenoceptor levels or cAMP production took place during the next 7 days. Plasma catecholamine levels were elevated at arrival and decreased steadily during the withdrawal period.In conclusion, chronic alcoholism is associated with a reduction of lymphocytic β‐adrenoceptor density and functioning, which is followed by a rapid reversal during abrupt ethanol withdrawal. Thus an accelerated responsiveness to catecholamines may occur during the first ethanol‐free day of chronic alcoholics.