bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cardiovascular Responses to Sustained Handgrip in Normal Subjects and in Patients with Diabetes Mellitus: A Test of Autonomic Function
Authors: Ewing D. J. , Irving J. B. , Kerr F. , Wildsmith J. A. W. , Clarke B. F. 
Published: August 2015

1. The blood pressure and heart rate responses to static muscular exercise were measured in sixty normal subjects and 124 patients with diabetes mellitus, aged 25–54 years, during a standardized sustained handgrip test at 30% maximum voluntary contraction (MVC).
2. The normal range of the response was established. Females had a smaller blood pressure rise than males, and their MVC was lower. In the normal subjects there was a significant correlation between the size of the MVC and the height of the blood pressure response. The absolute muscle tension exerted should be taken into account in addition to the percentage MVC, when comparing responses to sustained exercise in different disease states.
3. The diabetic subjects showed a similar sex difference in their response. The mean diastolic blood pressure rises were smaller than in the control groups, both in males and females, but this was related to a smaller mean MVC.
4. Twenty-two of the diabetic subjects had an abnormally low response to sustained handgrip, which was not related to age, duration of diabetes, treatment or control of the disease. These diabetic subjects probably had damage of the autonomic fibres mediating the response. The findings would suggest that sustained handgrip is a useful and simple method of detecting involvement of the autonomic nervous system in diabetes.
Changes in Disappearance of Intravenously Administered 47Ca at the Onset of Alimentary Absorption of Unlabelled Calcium
Authors: Kocián J. , Brodan V. 
Published: August 2015

1. Administration of a large amount of unlabelled calcium orally 60 min after intravenous injection of 47Ca leads to a temporary rise of serum specific radioactivity in healthy volunteers.
2. This short-term rise is followed by a more rapid decline and in some instances by oscillations of specific radioactivity.
3. Both these effects could be caused by secretion of thyrocalcitonin resulting from a rise of serum calcium concentration during calcium absorption from the gastrointestinal tract.
Absorption of two Tripeptides by the Human Small Intestine: A Study Using a Perfusion Technique
Authors: Silk D. B. A. , Perrett D. , Webb Joan P. W. , Clark M. L. 
Published: August 2015

1. A double-lumen perfusion technique has been used in man to study intestinal absorption of two tripeptides, glycyl-glycyl-glycine and l-alanyl-glycyl-glycine. Intraluminal tripeptide hydrolysis has been investigated by incubating both tripeptides in vitro with fresh uncentrifuged saline aspirates.
2. Glycine was absorbed faster from a glycyl-glycyl-glycine solution (3·3 mmol/l) than from an equivalent (10 mmol/l) glycine solution, and both l-alanine and glycine were absorbed faster from 10 mmol/l l-alanyl-glycyl-glycine than from the equivalent amino acid mixture. Free amino acids and dipeptides were aspirated during the tripeptide perfusions.
3. l-Alanyl-glycyl-glycine was hydrolysed faster than glycyl-glycyl-glycine in vitro, and results indicated that hydrolysis of the tripeptides occurred from the N-terminal end of the molecule. Intraluminal tripeptide hydrolysis was not sufficient to account for the concentrations of free amino acids and dipeptides liberated during the tripeptide perfusion experiments in vivo.
4. It is suggested that the liberated amino acids and dipeptides either diffused back into the luminal contents after hydrolysis in the brush border had taken place, or effluxed from the mucosal cell after intracellular tripeptide hydrolysis.
Depression of Erythrocyte δ-Aminolaevulinic Acid Dehydratase Activity in Alcoholics
Authors: Krasner N. , Moore M. R. , Thompson G. G. , McIntosh W. , Goldberg A. 
Published: August 2015

1. δ-Aminolaevulinic acid (ALA) dehydratase, γ-glutamyl transpeptidase (γGT) and leucine aminopeptidase (LAP) have been measured in chronic alcoholics.
2. Within 48 h of alcohol withdrawal ALA dehydratase activity was depressed in chronic alcoholics even though the blood alcohol content was zero. A second group of chronic alcoholics studied 7 days after the cessation of alcohol consumption had normal ALA dehydratase activities.
3. ALA dehydratase activity is more reliable than measurements of γGT and LAP in monitoring alcohol habits of chronic alcoholics.
Effects of Nucleotides, Hormones, Ions and 1,25-Dihydroxycholecalciferol on 1,25-Dihydroxycholecalciferol Production in Isolated Chick Renal Tubules
Authors: Larkins R. G. , MacAuley S. J. , Rapoport A. , Martin T. J. , Tulloch B. R. , Byfield P. G. H. , Matthews E. W. , MacIntyre I. 
Published: August 2015

1. The production of 1,25-dihydroxycholecalciferol (1,25-DHCC) from tritiated 25-hydroxycholecalciferol (25-HCC) was assessed in renal tubules prepared from vitamin D-deficient chicks.
2. Cyclic AMP and dibutyryl cyclic AMP enhanced the production of 1,25-DHCC.
3. Bovine parathyroid hormone (BPTH) and its synthetic analogue either had no effect or inhibited the production of 1,25-DHCC when calcium was present in the extracellular medium, but enhanced the conversion when calcium was absent. BPTH increased adenylate cyclase activity and cyclic AMP content of the renal tubule cells.
4. Synthetic salmon calcitonin enhanced the production of 1,25-DHCC, whereas human calcitonin had no effect at the concentrations tested. Salmon calcitonin did not increase chick renal adenylate cyclase activity or cyclic AMP levels.
5. A short period of incubation in media containing strontium gluconate (5 mmol/l) significantly increased production of 1,25-DHCC, whereas no effect was seen after more prolonged exposure to strontium. Calcium depletion decreased production of 1,25-DHCC, but when some calcium was present, variation in extracellular concentration of calcium did not affect conversion. Variation in extracellular phosphate concentration did not affect conversion.
6. A small quantity of 1,25-DHCC added to the medium inhibited the conversion of 25-HCC into 1,25-DHCC.
7. The production of 1,25-DHCC is subject to complex control, and intracellular concentrations of calcium, cyclic AMP and 1,25-DHCC may all be important regulatory influences.
Influence of Deoxycholic Acid Feeding on the Elimination of Cholesterol in Normolipaemic Subjects
Authors: Einarsson K. , Hellström K. , Kallner M. 
Published: August 2015

1. The turnover of [24−14C]cholic acid and [3H]chenodeoxycholic acid and the faecal excretion of neutral steroids were studied in six normolipaemic subjects before and during the ingestion of 1.3–2.6 mmol (0.5–1.0 g) of deoxycholic acid/day. Before the second study the subjects had been fed deoxycholic acid for 2 weeks.
2. The administration of deoxycholic acid did not appear to influence cholesterol metabolism as judged by the absence of change in the serum concentrations and the overall transformation into primary bile acids and neutral faecal steroids.
3. During the deoxycholic acid feeding period the mean total synthesis of bile acids was reduced by about 30%, corresponding to approximately 0.25 mmol (100 mg)/day. In one subject the pool size and in another the synthesis of cholic acid remained unchanged; otherwise the cholic acid pool size and its rate of formation decreased in all subjects. No consistent effects were observed with regard to the turnover of chenodeoxycholic acid.
4. Assuming that the bile acid turnover is equivalent to bile acid excretion then the total amount of cholesterol eliminated as bile acids and neutral faecal steroids averaged between 1.6 and 1.8 mmol/day before and during the administration of deoxycholic acid.
The Effects of Exogenous Parathyroid Hormone on Plasma and Urinary Adenosine 3′,5′-Cyclic Monophosphate in Man
Authors: Tomlinson S. , Barling P. M. , Albano J. D. M. , Brown B. L. , O'Riordan J. L. H. 
Published: August 2015

1. Administration of highly purified bovine parathyroid hormone (BPTH) (200 MRC units) increased the concentration of adenosine 3′,5′-cyclic monophosphate (cyclic AMP) in the peripheral plasma of normal subjects within minutes, whether the hormone was given as a bolus injection or an infusion.
2. The subsequent disappearance of cyclic AMP from the circulation was also rapid (t1/2 = 14 min) and was associated with a prompt decline (t1/2 = 4.6 min) in the concentration of the ammo-terminal part of BPTH, as measured in a region-specific immunoradiometric assay.
3. The concentration of cyclic AMP in plasma from a renal vein was found to increase more rapidly and to reach a greater peak than plasma from a peripheral vein.
4. The administration of BPTH to anephric subjects caused no increase in cyclic AMP.
5. These investigations indicate that parathyroid hormone can act extremely rapidly, with a short half-life, and that the kidney makes a major contribution to the changes in plasma cyclic AMP induced by the hormone. In addition, they form the basis for the development of a simplified Ellsworth—Howard test, using changes in circulating cyclic AMP after BPTH administration as an index of responsiveness to the hormone.
The Role of Plasma Volume in the Increase of Aldosterone Secretion Rate during Sodium Deprivation
Authors: Dalakos T. G. , Streeten D. H. P. 
Published: August 2015

1. 24 h aldosterone secretion rates (ASR) have been measured in six normal volunteers while recumbent all day and while standing for 12 h, on 200 and 10 mmol/day sodium diets and after salt-poor albumin infusions (75 g in 150 ml), which significantly expanded plasma volume.
2. The mean ASR on the 10 mmol/day sodium diet, both without and with the salt-poor albumin infusion, was highly significantly increased above the mean ASR on the 200 mmol/day sodium diet, both in the recumbent and in the upright posture.
3. There was no significant difference between the mean ASR values on the 10 mmol/day sodium diet alone and after the infusion of albumin either in the recumbent or in the upright posture.
4. The above observations suggest that sodium deprivation raises ASR by a mechanism or mechanisms unrelated to plasma volume.
Effects of Abdominal Breathing on Distribution of Ventilation in Obstructive Lung Disease
Authors: Grimby G. , Oxhøj H. , Bake B. 
Published: August 2015

1. The regional distribution of ventilation was studied with a 133Xe wash-out technique both after rebreathing and after intravenous injection of the isotope in six patients with chronic obstructive lung disease. Measurements were performed in the sitting position during spontaneous and augmented abdominal breathing respectively. The contribution to ventilation of the rib-cage and abdomen was measured with magnetometer recordings of the respiratory variation in the antero-posterior diameters.
2. The relative contribution of the abdomen to ventilation increased from about 40% during spontaneous breathing to about 67% during augmented abdominal breathing.
3. There was no systematic difference in the ventilation distribution between the two breathing patterns.
Role of Saline Consumption in the Prevention of Deoxycorticosterone Hypertension in Rats by Central 6-Hydroxydopamine
Authors: Lewis P. J. , Dargie H. J. , Dollery C. T. 
Published: August 2015

1. The mechanism by which pretreatment of rats with intracisternal 6-hydroxydopamine prevents the onset of deoxycorticosterone hypertension has been studied.
2. Rats pretreated with central 6-hydroxydopamine increase their consumption of 0.17 mol/l sodium chloride-0.03 mol/l potassium chloride (‘saline’) less than normal rats when implanted with deoxycorticosterone.
3. Intact rats restricted to the equivalent consumption of saline of rats pretreated with 6-hydroxydopamine develop hypertension despite this restriction.
4. It is suggested that the prevention of deoxycorticosterone hypertension by central 6-hydroxydopamine does not depend on reduced saline consumption.
Adaptations in Urea Ammonium Excretion in Metabolic Acidosis in the Rat: A Reinterpretation
Authors: Oliver Jane , Bourke E. 
Published: August 2015

1. The effects of oral hydrochloric acid, ammonium chloride, sodium bicarbonate and ammonium bicarbonate on urea and ammonium excretion in rats on a constant diet were studied.
2. Hydrochloric acid acidosis significantly reduced urea excretion in the rat, with an equimolar increase in NH+4 excretion and no change in their sum. In ammonium chloride acidosis, most of the additional nitrogen intake is excreted as NH+4 and a small percentage as urea. The converse holds true after administration of ammonium bicarbonate. The physiological significance of this is discussed.
3. The shift in nitrogen excretion from urea to NH+4 in acidosis is interpreted on the basis of bicarbonate production and utilization. Urea formation utilizes HCO−3. For amino acid sources, this utilization is offset by the metabolism of the carbon skeleton, which gives rise to HCO−3. When waste nitrogen is excreted as NH+4, no bicarbonate is utilized and the new HCO−3, generated by the carbon skeleton, helps to maintain hydrogen ion homeostasis.
Abnormal Sodium Transport in Leucocytes from Patients with Essential Hypertension and the Effect of Treatment
Authors: Thomas R. D. , Edmondson R. P. S. , Hilton P. J. , Jones N. F. 
Published: August 2015

1. In seventeen patients with untreated essential hypertension the sodium and water contents of leucocytes were significantly increased, whereas the rate constant for ouabain-sensitive sodium efflux was significantly reduced.
2. These abnormalities were not found in fourteen other patients with well-controlled hypertension.
3. Preliminary observations in accelerated hypertension suggest a different pattern of abnormality in leucocyte sodium metabolism.
Prazosin: Preliminary Clinical and Pharmacological Observations
Authors: Bolli P. , Wood A. J. , Phelan E. L. , Lee D. R. , Simpson F. O. 
Published: August 2015

1. Prazosin had a considerable anti-hypertensive effect in both lying and standing posture in a mixed group of twenty-four patients in an open clinical trial. The drug was well tolerated and side-effects were few.
2. Tested on rat blood vessels, prazosin was ten times more potent on a molar basis than phentolamine in blocking the vasoconstrictor effects of noradrenaline. In the absence of vasoconstrictor nervous activity, no vasodilatation was observed.
3. In genetically hypertensive rats, prazosin in large doses caused a substantial fall in blood pressure, total exchangeable sodium and extracellular fluid volume. Tolerance to these effects started to develop within 20 days. In normotensive rats, blood pressure was lowered but total exchangeable sodium and extracellular fluid volume were not affected.
Body Weight and Body Water in Chronic Cor Pulmonale
Authors: Campbell R. H. A. , Brand Hilary L. , Cox J. R. , Howard P. 
Published: August 2015

1. Body weight was measured through forty consecutive illnesses in seventeen patients with oedema in association with chronic bronchitis and hypoxia. All patients were taking diuretic drugs at the time.
2. Body weight increased little as peripheral oedema and a raised jugular venous pressure appeared. The subsequent weight-loss during treatment was usually greater than the pre-treatment weight-gain. Body weight increased slowly in convalescence to equal or exceed hospital admission weight without a deterioration of general health or reappearance of oedema.
3. Total body water, exchangeable sodium and exchangeable potassium were measured in patients after treatment of the acute illness and clearance of oedema and again in six patients of the group 2–3 months later in convalescence. Total exchangeable sodium was normal or slightly reduced after treatment of oedema and in convalescence between recurrent acute illnesses. Even when gross oedema was present exchangeable sodium was substantially increased in only one of three patients studied at this stage. Total exchangeable potassium was invariably severely depressed.
4. Large changes of body tissue weight without comparable change in exchangeable sodium support previous evidence that oedema in hypoxic bronchitis is not simply a further form of congestive cardiac failure.
5. It is suggested that at least some of the tissue loss in acute exacerbations is a direct result of hypoxaemia and similar to that observed at high altitude. Part of the oedema fluid is thought to be derived from intracellular water released during dissolution of tissue matrix.
Observations on the Passage of Apoproteins from Plasma Lipoproteins into Peripheral Lymph in Two Men
Authors: Reichl D. , Postiglione A. , Myant N. B. , Pflug J. J. , Press M. 
Published: August 2015

1. The passage of radioactive apolipoproteins into lymph draining the foot was investigated in two men, each given a single intravenous injection of low-density lipoprotein containing 131I-labelled apoprotein B and of very-low-density lipoprotein containing 125I-labelled apoprotein A and apoprotein C.
2. Protein-bound 125I and 131I appeared in the lymph of both subjects. Immunoelectrophoresis of lymph lipoproteins against anti-(high-density lipoprotein) and anti-(low-density lipoprotein) showed the presence of apo-high-density lipoprotein and apo-low-density lipoprotein with faster mobilities than plasma high-density and low-density lipoprotein respectively. Most of the protein-bound 131I in lymph was recovered in the precipitin line formed by the apoprotein B-containing lipoprotein after immunoelectrophoresis. Polyacrylamide gel electrophoresis of the lymph lipoprotein fraction showed the presence of 125I-containing bands with mobilities similar to those of the apoprotein A of high-density lipoprotein and of three of the fast-moving C apoproteins.
3. These results suggest that most, if not all, of the apoproteins of plasma lipoproteins reach the interstitial fluids and that some lipoproteins undergo modification during their passage into peripheral lymph.
The Effect of Reduction in Blood Volume on Plasma Renin Activity in Man
Authors: Hesse B. , Nielsen I. , Hansen J. F. 
Published: August 2015

1. The blood volume was reduced by approximately 10% in nine adult humans.
2. Plasma renin activity was measured before and at intervals after the venesection. In seven subjects there was no significant change. In two subjects there was a slight but significant increase in plasma renin activity.
3. It is concluded that reduction in blood volume is not a major short-term factor in regulating renin production in humans.
Measurement of Muscle Protein Synthetic Rate from Serial Muscle Biopsies and Total Body Protein Turnover in Man by Continuous Intravenous Infusion of l-[α-15N]lysine
Authors: Halliday D. , McKeran R. O. 
Published: August 2015

1. Five healthy male subjects were studied by continuous infusion of l-[α-15N]lysine over 20–30 h with timed blood and urine samples, and two or three percutaneous needle biopsies of vastus lateralis muscle.
2. A standard creatine-free diet, quantitatively related to body surface area, was given for 5 days before the infusion. The [15N]lysine was administered at a constant rate in an amino acid solution with a nitrogen content of 0·96 mol/l, which constituted the sole source of exogenous nitrogen during the infusion.
3. A plateau level of plasma free [15N]lysine enrichment was achieved after infusion for 14 h. The total plasma lysine flux calculated from the plateau was 7·3 mmol/h (range 4·8–9·6). Total body protein turnover calculated from the lysine flux was 3·5 g day−1 kg body wt.−1 (range 2·5–5·0).
4. Muscle sarcoplasmic and myofibrillar fractions were separated, purified and the 15N enrichment was measured. The sarcoplasmic protein fractional synthetic rate was calculated as 3·8%/day (range 2·2–5·1). The myofibrillar protein synthetic rate was 1·46%/day (range 1·09–2·44).
5. Muscle mass, calculated from 24 h creatinine excretion, was 33·7 kg (range 28·8–37·4), which represented 500% of body weight (range 38·9–58·1). Total muscle protein synthesis was calculated to account for 53·2% (range 39·5–62·1) of total body protein synthesis.
6. The advantages and limitations of using continuous infusion of [15N]lysine in human subjects are discussed.
Relation between Hepatic Alcohol Dehydrogenase Activity and the Ascorbic Acid in Leucocytes of Patients with Liver Disease J. Dow
Authors: Dow J. , Krasner N. , Goldberg A. 
Published: August 2015

1. Hepatic alcohol dehydrogenase activity and leucocyte ascorbic acid content were measured in thirty-five patients with liver disease and in ten control subjects with duodenal ulcer. The patients with liver disease were divided into three groups consisting of non-drinkers, moderate drinkers and alcoholic/heavy drinkers.
2. There was no significant difference in hepatic alcohol dehydrogenase activity between the groups with liver disease, but all patients had less than half the hepatic alcohol dehydrogenase activity of the control subjects (P < 0·001).
3. The ascorbic acid in leucocytes was significantly lower in the alcoholic/heavy drinker group than that in the control subjects (P < 0·02) when the Student's t-test was applied, but no significant difference was found when the Mann—Whitney U-test was used.
4. A correlation coefficient of r = 0·77 (P < 0·001) was observed among the thirty-five patients with liver disease when hepatic alcohol dehydrogenase activity was compared with leucocyte ascorbic acid content. An insignificant correlation (r = 0·332) was found in the control subjects with no liver disease.
5. This comparison was also significant among non-drinkers with liver disease (r = 0·873; P < 0001), moderate drinkers (r = 0·739; P < 0·02) and alcoholic/heavy drinkers (r = 0·702; P < 0·005).
6. The addition of ascorbic acid in vitro (0·5–10 mmol/l) had no effect on the activity of alcohol dehydrogenase.
7. The relation between hepatic alcohol dehydrogenase activity and leucocyte ascorbic acid content is probably a consequence of liver disease, as opposed to any specific effect of ascorbic acid deficiency or alcohol consumption on alcohol dehydrogenase activity.