bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Inhibition of Lipid Autoxidation by Human Serum and its Relation to Serum Proteins and α-Tocopherol
Authors: Stocks J. , Gutteridge J. M. C. , Sharp Rosemary J. , Dormandy T. L. 
Published: August 2015

1. The inhibitory (antioxidant) effect of serum on the autoxidation of tissue polyunsaturated fatty acids has been investigated.
2. Dialysis studies, DEAE-cellulose chromatography, gel filtration, immunoelectrophoresis and immunodiffusion experiments showed that this effect is the function of two serum protein fractions.
3. One fraction was identified as transferrin. The second fraction includes caeruloplasmin.
4. Studies with radioactively labelled α-tocopherol showed that serum tocopherol in the physiological concentration range contributes only marginally to the total antioxidant activity of serum.
5. These findings are discussed in the wider context of biological antioxidant protection.
Plasma Free Fatty Acid and Triglyceride Transport Kinetics in Man
Authors: Kissebah A. H. , Adams P. W. , Wynn V. 
Published: August 2015

1. Studies were carried out to test the assumptions involved in the calculation of free fatty acid (FFA) and triglyceride transport rates from the plasma radioactivity curves after the intravenous administration of labelled fatty acid or of pre-labelled lipoprotein triglyceride.
2. Plasma FFA equilibrates reversibly with the interstitial lymph. This makes it necessary to use either a pulse injection, with analysis of the results in terms of a two-compartment model, or continuous infusion of the label in determining the FFA flux.
3. The recycling of labelled fatty acid due to direct hydrolysis of plasma triglyceride accounted for less than 5% of the total plasma FFA flux and did not appreciably affect the plasma triglyceride disappearance curve after endogenous labelling with 14C-labelled fatty acid. Turnover values calculated from triglyceride in unfractionated plasma represent mainly the very-low-density lipoprotein triglyceride transport. The distribution space of plasma triglyceride was found to be equal to the plasma volume.
4. Our findings suggest a complex relation between plasma triglyceride concentration and its transport kinetics. The plasma triglyceride concentration is determined by the rates of influx and efflux, and this concentration also regulates its own production and removal. Evidence obtained from the endogenous labelling technique and after experimental hypertriglyceridaemia suggests the application of enzyme kinetic models to characterize plasma triglyceride transport.
Aldosterone and its Regulation during Diuresis in Patients with Gross Congestive Heart Failure
Authors: Nicholls M. G. , Espiner E. A. , Donald R. A. , Hughes H. 
Published: August 2015

1. Plasma aldosterone concentration and urine aldosterone excretion were studied before and during sustained diuresis in six patients with gross congestive heart failure, under conditions of fixed sodium and potassium intake and strict control of body posture. Simultaneous measurements of plasma renin activity, plasma corticotrophin and electrolytes were made to assess the relative importance of these factors in the regulation of aldosterone secretion before and during treatment of congestive heart failure.
2. During the pre-treatment phase aldosterone levels were normal or raised, but with acute diuresis fell to unmeasurable levels in most cases. This depression in aldosterone tended to coincide with peak natriuresis. Later in the diuretic phase aldosterone values increased often to very high levels as dry body weight was attained.
3. With few exceptions plasma renin activity fluctuations paralleled those of plasma aldosterone, whereas corticotrophin levels remained largely within normal limits and plasma electrolytes did not change appreciably.
4. The results suggest that the renin—angiotensin system is the important regulator of aldosterone secretion before and during diuretic treatment in patients with gross congestive heart failure.
Quantitative Radioisotope Renography: The Derivation of Physiological Data by Deconvolution Analysis Using a Single-Injection Technique
Authors: Reeve J. , Crawley J. C. W. 
Published: August 2015

1. An improved method is presented for quantifying all the information relating to individual kidney function that is contained in the renogram.
2. From the convolution theorem, functions are derived which are equivalent to the renograms that would be obtained by simultaneous injections of the indicator into each renal artery, fractionated according to renal blood flow.
3. The ‘pulse-input’ renograms so derived can have the blood background subtracted by a process of ‘kinetic discrimination’, which dispenses with the prior injection of human serum albumin.
4. The ‘pulse-input’ renograms with blood background subtracted are analysed by the techniques used in conventional indicator dilution methods.
5. The value of this approach in clinical and experimental work is illustrated by comparison of examples drawn from 400 consecutive studies of patients with normal data.
Specificity of Blockade of Renal Renin Release by Propranolol in the Cat
Authors: Johns E. J. , Singer Bertha 
Published: August 2015

1. The anaesthetized cat, unilaterally nephrectomized and with renal nerves sectioned, has been used in a study of the specificity of the inhibitory effect of propranolol on renin release.
2. The effect of (+)-propranolol on the rise in plasma renin activity (PRA) induced by renal nerve stimulation has been examined. When administered at approximately the same dose as the racemic mixture which blocks renin release in response to this stimulus, (+)-propranolol did not significantly reduce the magnitude of the response. Therefore the action of racemic propranolol in blocking the response to neural stimulation can be attributed to the (−)-isomer.
3. Renal artery constriction, producing blood flow changes similar to those resulting from renal nerve stimulation, also induces a rise in PRA. (±)-Propranolol, in amounts which block the rise in PRA observed with renal nerve stimulation, did not prevent the increase seen with renal artery constriction.
4. Reduction of renal perfusion pressure within the autoregulatory range for 20 min resulted in a rise in PRA in all experiments. (±)-Propranolol did not significantly affect the response.
5. It is concluded that the release of renin in response to renal nerve stimulation cannot be attributed to associated changes in renal blood flow. The evidence is compatible with a direct action of the neurotransmitter on renin-containing cells via a β-adrenergic receptor. When renin release is induced by non-adrenergic mechanisms propranolol blockade has no significant effect on the response.
Reduced Serum Somatomedin Activity in Patients with Chronic Liver Disease
Authors: Wu A. , Grant D. B. , Hambley Judy , Levi A. J. 
Published: August 2015

1. Somatomedin (SM; sulphation factor) activity was estimated by a chick-cartilage assay in fasting sera from twenty-one patients with chronic liver disease.
2. Low SM values were found in nine out of the ten patients with cirrhosis and in two other patients, one with hepatofibrosis and one with hepatoma.
3. In general, the lowest serum SM activities were found in those patients with the most severe disease and significant correlations were found between serum SM and serum albumin, alkaline phosphatase and bilirubin.
4. Growth hormone was also measured in the samples and concentrations above 10 units/ml were found in seven patients, all of whom had reduced serum SM activities.
5. These findings indicate that low serum SM activity in liver disease is not related to growth hormone deficiency and suggest that the liver may be an important site for SM synthesis in man.
Unesterified Fatty Acids and the Binding of Tryptophan in Human Plasma
Authors: Curzon G. , Friedel June , Katamaneni Bharati D. , Greenwood Monica H. , Lader M. H. 
Published: August 2015

1. The percentage of human plasma tryptophan in the free state (ultrafilterable) was positively and significantly correlated with plasma non-esterified fatty acid (NEFA) concentration.
2. Results obtained either by adding tryptophan to plasma in vitro or from plasma taken during tryptophan infusion indicate one tryptophan binding site per albumin molecule and an inverse relationship between binding constants and NEFA concentration.
3. A single normal subject was atypical as the apparent number of binding sites varied between one and two per albumin molecule (1.54±0.49 sd, four experiments).
4. Spontaneous increases of plasma NEFA during tryptophan infusion were associated with increased free tryptophan. Also addition in vitro of linoleic acid, oleic acid and palmitic acid to plasma caused free tryptophan to increase.
5. The possible significance of NEFA changes on plasma tryptophan binding in various pathological circumstances is discussed.
Serial Studies of the Renal Clearance of Urate and Inulin during Pregnancy and after the Puerperium in Normal Women
Authors: Semple P. F. , Carswell W. , Boyle J. A. 
Published: August 2015

1. A serial study of renal clearance of urate and inulin was made in thirteen normal women in early, mid and late pregnancy and 6–15 weeks after delivery.
2. The mean serum urate concentration was low in early and mid pregnancy but rose in late pregnancy towards the control value.
3. Clearances of urate and inulin were consistently elevated throughout pregnancy to about 150% of the post-partum values. The ratio of clearance of urate to clearance of inulin was the same in pregnancy as it was after the puerperium.
4. The urinary excretion of urate was increased only in late pregnancy.
Experimental Acute Hepatic Encephalopathy: Comparison of the Electroencephalographic Changes in the Liverless and in the Eviscerated Rat
Authors: Degos Francine , Degos J.-D. , Bourdiau Denise , Peignoux Michèle , Prandi Danièle , Roche-Sicot Jacqueline , Sicot C. , Rueff B. , Benhamou J.-P. 
Published: August 2015

1. The present work was carried out to compare the electroencephalographic changes in liverless rats and eviscerated rats and to determine whether substances released from the intestine, in particular ammonia, play a major part in the mechanism of hepatic encephalopathy.
2. The animals were prepared according to a three-stage procedure: ligation of inferior vena cava; 3 weeks later, end-to-side portacaval shunt; 2 days later, removal of the liver (liverless rats) or removal of the liver, spleen, stomach, intestine and pancreas (eviscerated rats).
3. In liverless rats, the electroencephalographic changes began 4–8 h after hepatectomy with a predominance of ‘slow’ sleep pattern followed by increasing changes, which consisted successively of (a) alteration of, then disappearance of, spindles of high-voltage waves; (b) predominance of slow waves; (c) depression in voltage and finally flat tracing. The mean duration of survival was 18.4 h. Mean plasma ammonia concentration 15 h after hepatectomy was 353 μmol/l.
4. In eviscerated rats, the electroencephalographic changes were similar. The mean duration of survival was 21.3 h, which is not statistically different from that of liverless rats. Mean plasma ammonia concentration 15 h after evisceration was 148 μmol/l, a value significantly lower than that of liverless rats.
5. These results suggest that ammonia, and substances released from the intestine in general, play no part or at most a minor role in the mechanism of hepatic encephalopathy of the liverless rat.
Glutathione Peroxidase Deficiency with Increased Susceptibility to Erythrocyte Heinz Body Formation
Authors: Hopkins J. , Tudhope G. R. 
Published: August 2015

1. The production of Heinz bodies, after incubation of erythrocytes in the presence of hydrogen peroxide vapour, was significantly greater in erythrocytes with abnormally low glutathione peroxidase (GSH-Px) activity than in cells with normal enzyme activity.
2. The addition of the catalase inhibitor, sodium azide, to the incubation mixture, increased the formation of Heinz bodies after exposure to hydrogen peroxide vapour; the percentage of Heinz bodies was significantly greater in erythrocytes with low GSH-Px activity than in normal erythrocytes.
3. Erythrocyte GSH-Px deficiency thus predisposes the cell to Heinz body formation when exposed to oxidant stress.
Partial Pressures of Oxygen and Carbon Dioxide, and pH of Blood Sampled from Wedged Pulmonary Artery
Authors: Chlup J. , Šerf B. , Ouředník B. , Parkmannová A. 
Published: August 2015

1. Po2, Pco2 and pH were examined in twenty-seven pulmonary ‘wedge’ samples of blood obtained from seventeen patients with various heart diseases.
2. High Po2 and pH, and low Pco2, values were found in comparison with those in simultaneous samples of peripheral arterial blood. In the pulmonary ‘wedge’ samples of blood, the following mean values were found: Po2, 17.65 kPa (132.2 mmHg); Pco2, 3.10 kPa (23.2 mmHg); pH 7.47. An explanation of these findings is considered.
Measurement of Intrarenal Blood-Flow Distribution in the Rabbit Using Radioactive Microspheres
Authors: Warren D. J. , Ledingham J. G. G. 
Published: August 2015

1. Total renal blood flow and its distribution within the renal cortex of the conscious rabbit were studied with radioactive microspheres of 15 and 25 μm diameter.
2. The reliability of the microsphere technique was influenced by microsphere diameter and number (dose). The optimum microsphere diameter for determination of flow distribution in the rabbit kidney was 15 μm and dose 100–150 000 spheres.
3. Spheres of 15 μm nominal diameter were randomly distributed within the renal cortex of adult rabbits. The larger spheres in batches nominally 15 μm in diameter in young rabbits and 25 μm diameter in adult rabbits were preferentially distributed to the superficial cortex.
4. In adult rabbits 15 μm diameter spheres lodged in glomerular capillaries. Larger spheres occasionally lodged in interlobular arteries causing intrarenal haemorrhage.
5. Microspheres of 15 μm caused a decrease in renal clearance of creatinine and of p-aminohippurate when the total injection dose was about 200 000 spheres. These effects were greater when the injection dose was increased to 500 000 spheres.
6. The reduction in total renal blood flow observed with large doses of spheres largely reflected decreased outer cortical flow, as measured by a second injection of spheres, and confirmed by a decrease in p-aminohippurate extraction.
7. The reproducibility of multiple injection studies was limited by these intrarenal effects of microspheres.
8. Total renal blood flow measured in six rabbits in acute experiments by the microsphere technique was 107 ± 12 (mean±sd) ml/min and by p-aminohippurate clearance was 100 ± 10 ml/min.
9. Total renal blood flow in twelve conscious, chronically instrumented rabbits was 125 ± 11 ml/min, of which 92 ± 6 ml/min was distributed to the superficial cortex and 33 ± 4 ml/min to the deep cortex.
Deoxycorticosterone Excretion in Normal, Hypertensive and Hypokalaemic Subjects
Authors: Cope C. L. , Loizou S. 
Published: August 2015

1. Radioimmunoassay has been used to detect and estimate the urinary excretion of deoxycorticosterone (DOC) in normal, hypertensive and hypokalaemic subjects. The range of excretions in ten healthy normal subjects was 41–232 pmol (13.7–76.7 ng) daily, with a mean of 124 pmol (41 ng).
2. In fourteen subjects with essential hypertension without metabolic disturbance the range found was 29–144 pmol (9.7–47.7 ng) daily, with a mean of 87 pmol (28.8 ng), which is not significantly different from that in normal subjects.
3. In twelve patients with Cushing's syndrome due to adrenal cortical hyperplasia the range found was 26–542 pmol (8.7–179 ng). Ten of these twelve patients had values within normal limits.
4. Of nine subjects showing hypokalaemia, eight had elevated excretion of deoxycorticosterone with values from 263 to 5515 pmol (87–1820 ng) daily. Seven of these were hypertensive and two were normotensive. The elevated excretion of deoxycorticosterone found in hypokalaemic subjects is thus not confined to those with hypertension.
5. No correlation has been found between excretion rates for aldosterone and deoxycorticosterone. Raised excretion of the latter provides an indicator of disturbed adrenal cortical metabolism.
Stimulation of Calcium Absorption and Apparent Increased Intestinal 1,25-Dihydroxycholecalciferol in Rats Treated with Low Doses of Ethane-1-Hydroxy-1,1-Diphosphonate
Authors: Guilland D. , Trechsel U. , Bonjour J.-P. , Fleisch H. 
Published: August 2015

1. Ligated intestinal segments from rats treated with disodium ethane-1-hydroxy-1,1-diphosphonate (EHDP) at the daily dose of 16 μmol (1 mg of phosphorus)/kg subcutaneously for 7 days show an increased rate of calcium absorption.
2. This dose of EHDP enhances the intestinal accumulation of a vitamin D3 metabolite with the chromatographic characteristics of 1,25-dihydroxycholecalciferol.
Resin Column Perfusion with Whole Blood or Plasma Separated by the Continuous Flow Celltrifuge
Authors: Weston M. J. , Mellon P. J. , Langley P. G. , Hughes R. D. , Dunlop E. H. , Gazzard B. G. , Roger Williams 
Published: August 2015

1. The aim of this study was to define the factors influencing plasma separation from the continuous flow celltrifuge and to evaluate plasma as an alternative to whole blood for perfusion of exchange resins as part of a system of artificial liver support.
2. Studies in vitro showed the importance of packed cell volume, centrifugal force and duration of centrifugation on the degree of plasma separation. From these data it was possible to calculate plasma flow rates likely to be obtained from the celltrifuge when used in vivo. These predicted values correlated closely with plasma flow rates obtained in twenty-six studies in dogs.
3. Comparison of whole blood perfusion with plasma perfusion of exchange resins in another series of dog experiments showed that with whole blood perfusion there was often a considerable rise in pressure across the resin column but that this did not occur with plasma perfusion.
4. Measurements of platelet losses in the same series of experiments showed a 50% reduction of arterial platelet counts over a 3 1/2 h period of perfusion when whole blood was perfused. Although the fall was lower with plasma perfusion, the difference was not statistically significant.
5. Use of the celltrifuge provides a means of resin perfusion free of the mechanical difficulties of whole blood perfusion, but platelet losses still remain a problem.
Altered Membrane Sodium Transport and the Presence of a Plasma Ouabain-Like Inhibitory Factor in Acute Myeloid Leukaemia
Authors: Mir M. Afzal , Bobinski H. 
Published: August 2015

1. Sodium transport studies were performed in erythrocytes from normal subjects and from patients with acute myeloid leukaemia. Sodium influx and efflux rates were increased in erythrocytes from leukaemic patients.
2. The ouabain-sensitive component of sodium efflux was increased in leukaemic erythrocytes.
3. The high sodium efflux from leukaemic erythrocytes was decreased when the incubation media contained leukaemic plasma, suggesting the presence of an ouabain-like factor in the plasma. Paired experiments failed to show the presence of a similar factor in normal plasma.
4. Leukaemic erythrocytes showed a significantly greater ouabain uptake than the normal cells.
5. The results are discussed in relation to the widespread electrolyte disturbances in acute myeloid leukaemia.
Effect of Long-Acting Thyroid Stimulator on Serum Concentration of Luteinizing Hormone in the Rat
Authors: Dandona P. , El Kabir D. J. , Naftolin F. , MacKinnon P. C. B. 
Published: August 2015

1. The effect of long-acting thyroid stimulator (LATS) on the serum luteinizing hormone (LH) levels of the rat in pro-oestrus has been studied.
2. The injection of three out of four LATS-containing immunoglobulin G fractions caused an increase in amounts of serum LH.
3. Adrenalectomy and dexamethasone suppression did not alter this response.
4. Injection of large doses of adrenocorticotrophic hormone did not produce any increase in serum concentrations of LH.
5. It is postulated that LATS may have a direct effect on the release of LH from the pituitary gland.
Changes in Erythrocyte Membrane Ouabain-Sensitive Adenosine Triphosphatase after Renal Transplantation
Authors: Cole C. H. , Maletz R. 
Published: August 2015

1. Intracellular electrolytes, and erythrocyte membrane adenosine triphosphatase (ATPase) activity, was studied in twenty patients after renal transplantation.
2. The mean ouabain-sensitive ATPase activity in the erythrocyte membranes of the transplant patients was 122 nmol of inorganic phosphorus (Pi) h−1 mg of tissue−1 (sem 14), compared with 62 nmol of Pi h−1 mg of tissue−1 (sem 8) in a group of paired, healthy controls.
3. The increase in ouabain-sensitive ATPase was most marked in the 4 months after transplantation. However, a significant increase in ouabain-sensitive ATPase persisted for more than 8 months after transplantation.
4. This increase in ouabain-sensitive ATPase was associated with a decrease in intracellular sodium in the erythrocytes of the transplant patients.
Triglyceride, Free Fatty Acid and Carbohydrate Metabolism in Hyperlipaemic (Type IV) and Normolipaemic Subjects on Carbohydrate- or Fat-Rich Diets
Authors: Hagenfeldt L. , Hellström K. , Wahren J. 
Published: August 2015

1. Five patients with hyperlipoproteinaemia type IV and five normolipaemic controls were maintained on diets containing either a fat or a carbohydrate content of approximately 60%. Leg exchanges of triglycerides, free fatty acid (NEFA), glucose and other metabolites were measured in the basal state. The metabolic response to an intravenous glucose load and the turnover of intravenously infused [14C]oleic acid were determined. Individual fatty acids were analysed in plasma NEFA and very-low-density lipoprotein triglyceride.
2. No differences were detected between patients and controls with regard to leg uptake of triglyceride or NEFA on either diet. On shifting from a fat-rich to a carbohydrate-rich diet, the control subjects showed reduced values for arterial NEFA and for NEFA turnover, accompanied by a lowered release of NEFA and glycerol from the leg. In patients, on the other hand, the arterial concentration and turnover of NEFA remained unchanged and the release of glycerol from the leg increased. Glucose administration gave a less-pronounced fall of arterial NEFA on either diet in the patients and the incorporation of [14C]oleic acid into triglycerides after glucose administration was more marked than in the controls.
3. No difference in net uptake of triglyceride by the leg was demonstrable between patients and controls.
4. It is concluded that hyperlipaemic patients show an altered metabolic response to a carbohydrate-rich diet, possibly contributing to the development of a hyperlipaemic state, and that acute glucose loading results in a greater incorporation of circulating NEFA into very-low-density lipoproteins in these patients.