bluuebunny/crossref_metadata_2025 huggingface dataset:
The Absorption of Glycine and Glycine Oligopeptides by the Rat
Authors: Peters T. J. , MacMahon M. T.
Published: August 2015

1. Samples of portal venous and femoral arterial plasma and mesenteric lymph were collected from unanaesthetized rats before and during the intra-duodenal infusion of high concentrations (100 mmol/l) of glycine or glycine oligopeptides (up to and including tetraglycine).

2. There was a marked increase in the concentration of free glycine, and a small amount of diglycine was detected in all the fluids when the peptides were infused but not during the infusion of free glycine. No other glycine oligopeptides were detected.

3. Mesenteric lymph contained a similar concentration of glycine and diglycine to that found in portal blood, suggesting that the mesenteric lymph is a dialysate of portal plasma.

4. The results are interpreted as supporting a dual localization of peptidases within the enterocyte; glycine oligopeptides are hydrolysed to diglycine and free glycine at the brush border and the diglycine is hydrolysed within the cytoplasm.
Effect of Propranolol in Lactate-Induced Hypophosphataemia in Man
Authors: Bonn J. A. , Harrison Jean
Published: August 2015

1. Intravenous infusion of dl-sodium lactate induces hypophosphataemia in man.

2. β-Adrenergic blockade with propranolol does not prevent this fall in plasma phosphate.
Studies on the Sympathetic Control of Normal and Diseased Synovial Blood Vessels: The Effect of α and β Receptor Stimulation and Inhibition, Monitored by the 133Xenon Clearance Technique
Authors: Dick W. C. , Jubb R. , Buchanan W. W. , Williamson J. , Whaley K. , Porter B. B.
Published: August 2015

1. The half-life (T½) of the disappearance curve of 133Xe from the knee joint has been used as an indirect measure of synovial perfusion.

2. The effects of intra-articularly administered isoprenaline and noradrenaline and their respective blocking agents, propranolol and phentolamine, on the T½ values have been investigated in normal subjects and in patients with osteoarthritis and rheumatoid arthritis.

3. In normal subjects isoprenaline increased the clearance rate and this effect was blocked by propranolol. Noradrenaline decreased the clearance rate and this effect was blocked by phentolamine.

4. The injection of phentolamine in normal subjects caused an increase in synovial perfusion, suggesting the presence of a basal α-constrictor tone.

5. In the patients with osteoarthritis and rheumatoid arthritis quantitative differences were found in the responses to isoprenaline and noradrenaline and their respective blocking agents.

6. There appeared to be a qualitative difference in the case of phentolamine; it is possible that vasoconstrictor tone may be lost in inflamed joints.
Mechanisms of Dipeptide Uptake by Rat Small Intestine in Vitro
Authors: Cheng B. , Navab F. , Lis M. T. , Miller T. N. , Matthews D. M.
Published: August 2015

1. The uptake of l-methionine and glycine as free amino acids, and from their dipeptides by everted rings of rat small intestine in vitro has been investigated. The concentrations used covered a wide range, including values likely to be near those found in the lumen of the intestine.

2. Though no intact peptides were found in the mucosal cells, evidence was obtained which showed that hydrolysis of the peptides was cellular at all concentrations. Total hydrolysis of peptides by the intestine was very great in relation to amino acid uptake over very short incubation times, suggesting that much hydrolysis took place superficially.

3. Except at the lowest concentrations, the rates of uptake of amino acids from the peptides were more rapid than from the equivalent amino acid mixtures. Competition for uptake between glycine and methionine was avoided when they were presented in the form of l-methionylglycine.

4. Anoxia inhibited uptake of methionine from free l-methionine and from l-methionyl-l-methionine. It also inhibited hydrolysis of l-methionyl-l-methionine by intact intestine, but not by intestinal homogenates, suggesting that peptide uptake may be energy-dependent. The l-amino acid oxidase of snake venom, which destroys l-methionine but has no effect on glycine or on the peptides studied, inhibited methionine uptake from peptides when present at high concentrations, suggesting that a major site of hydrolysis is enzyme-accessible.

5. It is suggested that there may be two modes of uptake of amino acids from oligopeptides: (1) surface hydrolysis by mechanisms closely linked to the amino acid entry mechanisms, and (2) peptide entry into the mucosal cells by a special mechanism, followed by intracellular hydrolysis.
Serum Protein Changes after Injury
Authors: Clarke H. G. Minchin , Freeman T. , Pryse-Phillips W.
Published: August 2015

1. By means of a quantitative immunoelectrophoretic technique, serum protein changes have been followed in seven patients before and during the week following inguinal herniorrhaphy, and in a single case of influenza.

2. The twenty proteins studied are grouped according to whether they rise (orosomucoid, α1-antitrypsin, Gc-globulin, caeruloplasmin, haptoglobin, β1A–C-globulin and proteins numbered 45, 99, 101 and X); fall (pre-albumin, α2HS-glycoprotein and protein No. 9); or show no significant change (α2-macroglobulin, haemopexin). α1-Lipoprotein fell in the case of influenza but did not change in the hernia patients; α1-easily-precipitable-glycoprotein increased in the hernia cases only.

3. The nature of the ‘acute phase reaction’ and the factors which elicit it are discussed.
Modifications to the Technique of Two-Dimensional Immunoelectrophoresis
Authors: Davies D. R. , Spurr E. D. , Versey J. B.
Published: August 2015

1. An examination of the technique of two-dimensional electrophoresis as developed by Minchin Clarke & Freeman (1968) has resulted in improvements for its routine use.

2. These include the use of smaller plates, a re-designed modular electrophoresis tank and modifications in the method of preparing the plates and in the process of running the electrophoresis.
The Effect of Lung Deflation on Breathing in Man
Authors: Guz A. , Noble M. I. M. , Eisele J. H. , Trenchard Diana
Published: August 2015

1. The effect of lung deflation was studied during treatment of patients for spontaneous pneumothorax: (a) in four patients acute lung deflation was produced by opening the chest drain to the atmosphere and the immediate effect on breathing was observed and (b) breath-holding time and the ventilatory response to CO2 were determined on admission to hospital and after recovery in a further four patients.

2. Allowing one lung to deflate suddenly produced an immediate increase in respiratory rate and electrical activity in inspiratory muscles.

3. Maximum breath-holding times were always decreased by pneumothorax.

4. In the presence of pneumothorax, the ventilatory response to rebreathing CO2 was increased at the break point, the respiratory rate was increased and the Pco2 at the breakpoint decreased in three out of four patients.

5. These results are consistent with the hypothesis that lung deflation has a reflex excitatory effect on breathing (Hering—Breuer deflation reflex). If this hypothesis is correct, it would appear that the threshold for the reflex is higher than for other mammalian species.
Measurement of Interstitial ‘Fluid’ Pressure by Means of a Cotton Wick in Man and Animals: An Analysis of the Origin of the Pressure
Authors: Snashall P. D. , Lucas J. , Guz A. , Floyer M. A.
Published: August 2015

1. A method for measuring interstitial ‘fluid’ pressure by using a wick consisting of long-stranded cotton wool at the interface of the tissue is described.

2. A correct measurement of hydrostatic fluid pressure was obtained when the wick, connected to a suitable transducer, was applied to filter paper in which the channels contained fluid at a known subatmospheric pressure.

3. A mean subatmospheric pressure of −1.6 cmH2O was recorded in the subcutaneous tissue of the normally hydrated frog; pressure fell with dehydration and rose with overhydration.

4. A mean subatmospheric pressure of −2.8 cmH2O was recorded in the subcutaneous tissues of the abdominal wall and scalp of the normally hydrated rat. Simultaneous measurements made at symmetrical sites showed a high degree of correlation.

5. A comparison of interstitial ‘fluid’ pressure in the subcutaneous tissues of the scalp (measured by a wick) and the abdominal wall (measured by a Guyton capsule), in both anaesthetized and conscious rats showed some degree of correlation. There was, however, a wide scatter of values.

6. The interstitial ‘fluid’ pressure in the rat, measured by both wick and capsule, became more negative when the animals underwent frusemide diuresis; the capsule pressures fell more rapidly for a given degree of fluid loss.

7. The wick method was applied to the subcutaneous tissues of the arm in normal man; a mean atmospheric pressure of −3.4 cmH2O was recorded in five subjects. There were no untoward sequelae.

8. The forces responsible for the measured pressure have been analysed. The recorded subatmospheric interstitial ‘fluid’ pressure in the rat rose towards atmospheric pressure and sometimes became positive when the wick was removed, soaked in increasing concentrations of hyaluronic acid, and reinserted in the tissues. This did not happen in similar experiments in which the wick was soaked in bovine albumin, rat plasma or saline. The large macromolecules of hyaluronic acid therefore exert a force which opposes the forces responsible for the subatmospheric interstitial pressure.

9. It is suggested that the apparent subatmospheric hydrostatic pressure is due to the osmotic forces developed by the hyaluronic acid molecules in the interstitial tissues trapped by their mutual entanglement in a sieve of collagen fibrils acting as a semipermeable membrane.
Potassium and Sodium Distribution in Cardiac Failure
Authors: Cox J. R. , Horrocks P. , Speight Carol J. , Pearson Rosemary E. , Hobson Norma
Published: August 2015

1. Total body water, extracellular fluid, total exchangeable potassium and total exchangeable sodium were measured by the multiple isotope-dilution technique in eight patients with congestive cardiac failure. Measurements were made on each patient while in failure and then again after treatment and recovery.

2. Compared with five control subjects in whom the same measurements were made, patients in failure had an excess of total body water, extracellular fluid and total exchangeable sodium, and had less total exchangeable potassium.

3. There was a decrease in total exchangeable sodium and an increase in total exchangeable potassium on recovery from congestive cardiac failure

4. After treatment of cardiac failure, intracellular potassium increased and intracellular sodium was decreased.

5. The low total exchangeable potassium in cardiac failure is not simply due to loss of lean body mass.
The Intramedullary Connections of the Area Postrema Involved in the Central Cardiovascular Response to Angiotensin II
Authors: Joy M. D.
Published: August 2015

1. The intramedullary connections of the area postrema involved in the central cardiovascular response to angiotensin were studied in the chloralose-anaesthetized greyhound.

2. In the intact animal the response to vertebral arterial infusions of angiotensin (32 ng/min for 5 min) was decreased by unilateral ablation of the area postrema suggesting that both areas postrema contribute to this response.

3. In the animal in which both vagi were blocked by cooling, the residual sympathetically mediated pressor response was unmodified by unilateral ablation of the area postrema suggesting that each area postrema can mediate the central sympathetic component of the response to angiotensin.

4. In the animal in which one vagus only had been blocked, unilateral ablation of the area postrema, irrespective of side, did not abolish the central cardiovascular response to angiotensin demonstrating that each area postrema can influence both vagi.

5. Midcollicular transection of the midbrain did not significantly alter the response to vertebral arterial infusions of angiotensin. This demonstrated that the central cardiovascular response to angiotensin is not dependent on connections with centres above the midbrain.

6. These results are consistent with the concept that the angiotensin-area postrema system is a neuro-humoral vasomotor centre afferent pathway.
Ventilatory Function in Healthy Adult Nigerians
Authors: Femi-Pearse D. , Elebute E. A.
Published: August 2015

1. Static and dynamic lung volumes (VC, FEV1, FRC, ERV, RV and TLC) have been determined in 291 adult healthy Nigerians (174 males and 117 females).

2. Prediction formulae of various authors on Caucasians and South African Bantu have been applied to the Nigerian data. The results show significantly smaller VC, FEV1, FRC, RV, TLC and RV/TLC in Nigerians than in Caucasians. The VC, FEV1 and FRC of Nigerians were similar to those of South African Bantu.

3. ERV values were similar to those previously reported by other authors for Caucasians. The combination of lower RV values and similar ERV indicates the possibility of less ‘basal airway closure’ in Nigerians.
The Effects of Hypoxia on Myocardial Blood Flow and Oxygen Consumption: Negative Role of Beta Adrenoreceptors
Authors: Vance J. P. , Parratt J. R. , Ledingham I. McA.
Published: August 2015

1. Myocardial blood flow was measured by using a 133xenon clearance technique in closed-chest dogs anaesthetized with trichlorethylene. A gradual decrease in the inspired oxygen tension resulted in an increase in myocardial blood flow only when the Pa,o2 fell to between 30 and 35 mmHg.

2. When hypoxia was rapidly induced and sustained for a mean period of 18.3 min, myocardial blood flow markedly increased (from a mean of 118 ± 5 to 162±6 ml 100 g−1 min−1). There was a critical mean arterial oxygen tension (35 mmHg) above which increases in myocardial blood flow did not occur. This corresponded to a mean coronary sinus Po2 of 18 mmHg or an oxygen content of 50 ml/100 ml. These flow increases were not dependent on changes in arterial or coronary sinus pH or carbon dioxide tension, nor were they dependent on changes in perfusion pressure or heart rate.

3. Despite the fact that oxygen availability was substantially decreased, myocardial oxygen consumption was maintained throughout the period of hypoxia by means of increased oxygen extraction.

4. Towards the end of the hypoxic period, Pa,co2 rose significantly from 40 ± 1 to 48 ± 1.5 mmHg. There was no significant change in the non-respiratory component of acid-base balance.

5. During prolonged hypoxia (more than 30 min) myocardial blood flow remained consistently elevated, but oxygen consumption tended to fall progressively and this was associated with an increasingly severe metabolic acidosis. The haemodynamic and oxygen consumption changes returned to normal within a short time (15 min) after the resumption of a normal inspired oxygen concentration, as did the frequently observed electrocardiographic disturbances.

6. The responses to hypoxia were unaffected by a combination of atropine and propranolol. There was no evidence either that hypoxia-induced coronary vasodilatation was mediated through vascular β-adrenoreceptors or that propranolol interfered with the self-regulating control of myocardial blood flow.

It has been recognized for some time that hypoxia is capable of producing considerable increases in blood flow in the myocardium (Hilton & Eichholtz, 1925; Eckenhoff, Haf kenschiel, Landmesser & Harmel, 1947; Berne, Blackmon & Gardner, 1957; Feinberg, Gerola & Katz, 1958; Aukland, Kiil, Kjekshus & Semb, 1967). Little is known, however, about the exact relationship between arterial oxygen tension and myocardial blood flow. Further, although several factors associated with hypoxia are known to influence myocardial blood flow, the relative importance of each is uncertain; such factors include a direct effect of hypoxia on coronary vascular smooth muscle and indirect effects relating to changes in perfusion pressure, heart rate, extravascular support and associated metabolic disturbances. Likewise, the influence of neurogenic factors on myocardial vascular tone during hypoxia has not been systematically examined.
The Role of the Diaphragm in the Sensation of Holding the Breath
Authors: Noble M. I. M. , Eisele J. H. , Frankel H. L. , Else Wendy , Guz A.
Published: August 2015

1. Block of the phrenic nerves in three normal subjects, produced by injection of lignocaine in the neck, caused alleviation of the thoracic sensation during breath holding and prolonged breath-holding time.

2. Injection of lignocaine in the neck without nerve block had no effect on breath holding sensation or breath-holding time.

3. A patient with a spinal-cord transection at the third cervical segment with paralysed diaphragm and chest wall, had no sensation in the chest or abdomen during breath holding.

4. This patient maintained normal ventilation by using hypertrophied sternomastoid muscles. During breath holding he experienced no sensation in the neck despite the presence of sternomastoid contraction.

5. There is previous evidence that complete muscular paralysis abolishes breath-holding sensation but that paralysis of all muscles innervated from spinal segments below the eighth cervical has no effect.
The Validity of Measurement of Mean Whole Body Intracellular Hydrogen Ion Activity Using 5,5-Dimethyl-2,4-Oxazolidinedione
Authors: Makoff D. L. , Reid M. J. , Khayim Y. Bar , Kuyt F.
Published: August 2015

1. To study the validity of mean whole-body intracellular hydrogen ion activity measurements ([H+]i) by the distribution of 14C-labelled 5,5-dimethyl-2,4-oxazo-lidinedione ([14C]DMO), eight anaesthetized dogs received three separate injections of iso-osmotic buffered chemical DMO, in cumulative doses of 50–2000 mg/kg body weight, following a control [H+]i determination by the 14C-tracer technique.

2. A correlation between dose of chemical DMO and measured [H+]i was found with a regression line of −Δ[H+]i = 23.27 + 16.45 [log DMO dose −2.41].

3. Although the results are consistent with active transport of DMO across cell membranes, other possible explanations such as altered cell buffering capacity by DMO loading and variable sequestration of DMO in the gastrointestinal tract must be considered.

4. There is no evidence for cellular binding of DMO.
The Plasma Clearance and Liver Uptake of Iron from Transferrin of Low and High Iron Saturation
Authors: Fletcher J.
Published: August 2015

1. Serum labelled with radioactive iron was adjusted to different degrees of iron saturation and clearance of the tracer from the circulation of rats and its uptake by liver and intestine were followed.

2. The results showed that: (a) plasma iron clearance did not vary according to whether labelled iron was attached to transferrin at high or low iron saturation; (b) uptake of labelled iron by the liver was greater from transferrin at high iron saturation than from transferrin at low saturation.

3. The results suggest the presence of a receptor mechanism in the liver similar to that previously shown in reticulocytes.
The Effect of Starvation and Diabetes on Glycolytic Enzymes in Human Adipose Tissue
Authors: Galton D. J. , Wilson J. P. D.
Published: August 2015

1. The activities of hexokinase (EC 2.7.1.1) and phosphofructokinase (EC 2.7.1.11) have been studied in homogenates of adipose tissue taken from human diabetics, fasting and control patients.

2. Three isoenzymes of hexokinase were observed with apparent Km values for glucose of 1.04 × 10-5 m, 2.6 × 10-4 m and 2.9 × 10-4 m, respectively.

3. No change in activity of hexokinase was found in adipose tissue of untreated diabetics (n = 22), treated diabetics (n = 13) or non-diabetic controls. However, fasting was associated with a decrease of approx. 40% in the activity of hexokinase in adipose tissue.

4. In contrast, there was a marked decrease in the activity of phosphofructokinase in adipose tissue from untreated diabetics (n = 24) which was restored to normal by either insulin therapy or treatment by hypoglycaemic drugs.

5. There was a negative correlation between the phosphofructokinase/hexokinase ratio in adipose tissue and the fasting blood glucose (P = 0.01) and the 2 h blood glucose (P = 0.03) after an oral glucose load (50 g).

6. The functional significance of the changes in enzyme activities is discussed in relation to the glucose intolerance of diabetes.
Breathing Patterns and Regional Ventilation Distribution in Tetraplegic Patients and in Normal Subjects
Authors: Bake B. , Fugl-Meyer A. R. , Grimby G.
Published: August 2015

1. The regional distribution of ventilation was studied with 133Xe techniques in the sitting position in six patients with complete traumatic transection of the cervical spinal cord, 3–40 months after the lesion, and in four normal subjects. The relative contributions of the rib cage and abdomen to ventilation were determined from chest-wall motions.

2. Total lung capacity (TLC) was decreased and residual volume increased in the patients. After correction for the decreased TLC, the distribution of the regional functional residual capacity in the tetraplegic patients was similar to that of the normal subjects. In the patients, where the abdomen contributed to about half of the tidal volume, decreased ventilation of basal regions was demonstrated from measurements of regional tidal volumes (Vtr) and regional 133Xe wash-in curves.

3. The distribution of ventilation in normal persons, however, was not changed by varying the relative contributions of the rib cage and abdomen to the tidal volume, as shown from Vtr and regional 133Xe wash-out measurements.

4. The results in the tetraplegic patients are interpreted as evidence of ‘small airway disease’, presumably from infection of the air way and impairment of the cough.
The Influence of Disodium Ethane-1-Hydroxy-1,1-Diphosphonate (Ehdp) on the Development of Experimentally Induced Urinary Stones in Rats
Authors: Fraser D. , Russell R. G. G. , Pohler Ortrun , Robertson W. G. , Fleisch H.
Published: August 2015

1. Bladder stones composed of calcium hydrogen phosphate dihydrate, calcium oxalate mono- and di-hydrate and magnesium ammonium phosphate hexahydrate (struvite) were successfully induced in rats by various dietary manipulations and by implanting zinc pellets in the bladder.

2. The effect of a diphosphonate, disodium ethane-1-hydroxy-1,1-diphosphonate (EHDP), given in the drinking water at concentrations of 0·0025, 0·05 and 0·5% (w/v), on the size and composition of these stones was examined.

3. All the concentrations of EHDP decreased the weight of the calcium oxalate calculi. In contrast, only the highest concentration of EHDP inhibited calcium hydrogen phosphate stone formation and the magnesium ammonium phosphate stones were unaffected.

4. The difference between the effects on calcium oxalate and magnesium ammonium phosphate stones is consistent with the finding that EHDP inhibited the precipitation of calcium oxalate from solution in vitro but had only a slight effect on magnesium ammonium phosphate precipitation.

5. It is suggested that EHDP might be of use in the prevention of some types of urinary stones in man.
Calcium Shift into Bone: A Calcitonin-Resistant Primary Action of Parathyroid Hormone, Studied in Rats
Authors: Robinson C. J. , Rafferty B. , Parsonsy J. A.
Published: August 2015

1. Parathyroid hormone (PTH) injected intravenously into rats caused a small rapid uptake of simultaneously administered radioactive calcium into the skeleton.

2. This skeletal uptake of calcium occurs in many other species, including the monkey and probably man. It appears to be an initiating event in PTH action on bone.

3. Although calcitonin prevents PTH-induced bone resorption, it did not affect this early calcium shift.

4. This evidence is discussed in connection with the possibility of combining calcitonin with some other agent for the treatment of osteoporosis.
An Evaluation of Rebreathing Methods for Measuring Mixed Venous P
co2 During Exercise
Authors: Godfrey S. , Wolf Eliana
Published: August 2015

1. Measurements have been made of mixed venous Pco2 (PV̄co2) by two methods during exercise at 50 and 100 W in five adult male subjects.

2. The equilibration (plateau) method and the extrapolation (Defares) method were performed alternately, five times each, during the steady-state exercise.

3. The coefficient of variation of PV̄,co2 by the extrapolation method was much higher than that of the plateau method. The PV̄,co2 can be estimated to within ± 1 mmHg by the plateau method, and the derived cardiac output to within ± 0·5 1/min in most cases. The cardiac output calculated by this method agrees closely with that found by direct methods in other studies, whereas the extrapolation method usually overestimates the cardiac output in adults.

4. It is suggested that the degree of variation in the extrapolation method is due to technical factors in construction of the line and to the difficulty of deciding what constitutes the end-tidal Pco2.
An Intrinsic Rhythm of Urinary Calcium Excretion and the Specific Effect of Bedrest on the Excretory Pattern
Authors: Ede M. C. Moore , Faulkner M. H. , Tredre Barbara E.
Published: August 2015

1. The diurnal rhythms of urinary calcium excretion were studied in healthy subjects under four different regimens in which diet, activity and posture were varied. The excretory rhythms observed were compared with those of potassium, obtained under the same conditions.

2. When the subjects were active throughout the day and night and were either fasting or eating standard three-hourly meals, an intrinsic calcium rhythm was isolated with maximum amounts excreted between 06.00 and 09.00 hours.

3. Continuous supine bedrest was found to have a specific effect on calcium excretion. The total 24 h excretion was markedly increased compared with that found on constant activity but on the same dietary regimen, and 78% of the increase occurred between 09.00 and 18.00 hours.
Distribution of Renal Blood Flow in Patients with Heart Disease
Authors: Fluck D. C. , Evans T. R. , Siggers D. C. , Crawley J. , Srivongse S. A.
Published: August 2015

1. The renal blood flow distribution has been studied by the Xe washout method in nineteen patients undergoing routine left-sided cardiac catheterization.

2. It was found that there were two separate groups, one in which the washout curve could be analysed by curve stripping into four exponentials, and one in which only three could be detected.

3. The mean cardiac output was found to be lower in the three-component group, whereas the mean glomerular filtration rate did not differ significantly between the two groups.

4. In the four-component group but not in the three-component group, significant linear correlations were detected between cardiac output and glomerular filtration rate, and between glomerular filtration rate and intrarenal blood flow distribution.

5. One suggestion was that the three component distribution of renal blood flow was associated with increasing renal autoregulation and the maintenance of renal function in the presence of a low cardiac output.

6. A second suggestion was that the differences between the three- and four-component group were primarily due to the more intensive diuretic therapy given to the patients in the three-component group.
Relationship between Haemodynamic and Respiratory Function in Patients with Myocardial Infarction and Left Ventricular Failure
Authors: Tattersfield Anne E. , McNicol M. W. , Sillett R. W.
Published: August 2015

1. Forty-five patients with myocardial infarction and clinical signs of left ventricular failure have been studied with measurements of pulmonary and brachial artery pressure, cardiac output, arterial blood gas pressures and expired air collections.

2. Pulmonary artery pressure was elevated and stroke index was reduced in the majority of patients (89% and 85% respectively). There was a close inverse correlation between these two measurements, both of which appear to be direct consequences of impaired left ventricular function.

3. Arterial hypoxaemia was common and only transiently relieved by hyperventilation. Dead space/tidal volume ratio and venous admixture were both increased, compatible with considerable ventilation/perfusion mismatching in the lung. Both measurements correlated directly with pulmonary artery pressure.
The Effect of Glucocorticoid Withdrawal on Body Water and Electrolytes in Hypopituitary Patients with Adrenocortical Insufficiency as Investigated with 77Br, 43K, 24Na and 3H2O
Authors: Skrabal F. , Arnot R. N. , Joplin G. F. , Fraser T. R.
Published: August 2015

1. Simultaneous measurements of exchangeable Na+, exchangeable K+, extracellular fluid volume and total body water, with 24Na, 43K, 77Br and 3H2O, were carried out in patients with adrenocortical insufficiency due to pituitary ablation performed 1–3 months previously.

2. The first group of five patients was studied before and after withdrawal of maintenance prednisone (2·5 mg three times daily, orally). The effects of glucocorticoid withdrawal were: (a) an increase in intracellular water (all cases) and a decrease in the extracellular fluid volume (four cases) irrespective of any change in serum Na+ concentration; (b) an increase in residual (‘intracellular’) Na+ in all cases which was matched by a loss of extracellular Na+, so that total body Na+ remained unchanged, and (c) the cortisol deficiency clinical syndrome. Exchangeable K+ remained unchanged.

3. Similar measurements were obtained with two further patients during the corticosteroid withdrawal period, throughout which they were kept on a maintenance dose of deoxycorticosterone acetate, 1·0 mg twice daily sublingually. Neither the above biochemical changes nor the cortisol deficiency syndrome developed.

4. The shift into the cells of water and Na+ may depend on the same defect caused by glucocorticoid deficiency, and may be the cause of the cortisol deficiency syndrome.
The Interrelations of Faecal Ammonia, pH and Bicarbonate: Evidence of Colonic Absorption of Ammonia by Non-Ionic Diffusion
Authors: Down P. F. , Agostini L. , Murison J. , Wrong O. M.
Published: August 2015

1. Ammonia, bicarbonate and pH were measured in samples of faecal dialysate from thirteen healthy subjects taking free diets. To observe the effect of marked changes in faecal pH, three subjects were also studied while taking 25 mmol/day of MgCO3 or Na2SO4 by mouth. Both salts increased stool weight without causing diarrhoea, but stool pH was significantly increased by MgCO3 and decreased by Na2SO4.

2. The total ammonia concentration and pH of faecal dialysate were very variable, but showed a highly significant negative correlation similar to that already established in man between urinary excretion of ammonia and urine pH. This relationship was more marked when individual subjects were studied while faecal pH was deliberately varied by administration of MgCO3 and Na2SO4.

3. Faecal bicarbonate concentrations were positively correlated with pH. Faecal Pco2 was usually in the range 40–120 mmHg, the higher Pco2 values being found in the more acid samples. Faecal total ammonia concentrations were negatively correlated with faecal bicarbonate.

4. These findings suggest that passive non-ionic diffusion is the main mechanism by which ammonia is absorbed by the colon, but do not exclude a minor contribution from diffusion of ionized ammonium. Colonic secretion of bicarbonate facilitates non-ionic diffusion of ammonia by providing an anion which is also absorbed by non-ionic diffusion, so maintaining an alkaline intraluminal reaction that continues to generate unionized ammonia.
Initial Increase of Plasma Radioactive Calcium after Intravenous Injection of Calcitonin in Man
Authors: Caniggia A. , Gennari C. , Piantelli F. , Vattimo A.
Published: August 2015

1. An intravenous infusion of calcitonin produced a sudden increase of plasma radioactivity after intravenous administration of 47Ca in man.

2. This effect was noted a few minutes before the well-known decrease of plasma calcium concentration.

3. A mathematical evaluation of this phenomenon demonstrated that: (a) it was significant in normal subjects, provided patients were given calcitonin 60–360 min after the intravenous injection of 47Ca; (b) it was generally not significant in patients with senile osteoporosis or osteomalacia; (c) it was particularly evident in patients with generalized Paget's disease or multiple myeloma.

4. Surface measurements performed on soft tissues and bone demonstrated a transient, simultaneous decrease of 47Ca radioactivity from bone.

5. The increase in plasma radioactivity implies a shift of 47Ca from reservoirs with high specific radioactivity, possibly bone cells, to the circulation.

6. According to these data two different mechanisms of action of calcitonin could be considered: an early effect on bone cells producing a shift of calcium to the circulation, and the well-known later hypocalcaemic effect through diminution of bone resorption.
Cortisol and Aldosterone Excretion and Plasma Cortisol Concentrations in Normal and Obese Female Subjects
Authors: Hankin Margaret E. , Theile Helen M. , Steinbeck A. W.
Published: August 2015

1. The 24 h urinary excretion of free cortisol and aldosterone-18-glucuronide has been studied in twenty-three control and twenty-three grossly obese subjects by a double-isotope-dilution derivative method.

2. Day-night variation of plasma and urinary cortisol has also been investigated.

3. The mean absolute steroid values were similar for the obese and non-obese subjects.

4. The 24 h urinary values for free cortisol expressed as μg/kg of body weight were significantly higher for the controls.

5. The majority of the obese and control subjects had a day-night variation of plasma cortisol. All subjects, with two exceptions, showed day-night variation of free cortisol in the urine.

6. It is suggested that the estimation of unconjugated cortisol in timed urinary collections could be useful for investigations of adrenocortical function.

7. The findings do not support the presence of increased adrenocortical activity in developed obesity.
Amounts of Faecal Porphyrin-Peptide Conjugates in the Porphyrias
Authors: Moore M. R. , Thompson G. G. , Goldberg A.
Published: August 2015

1. The levels of ‘X-porphyrin’, a porphyrin-peptide complex, have been studied in the faeces of patients with different types of porphyria, as well as in fifty normal subjects.

2. These levels have been shown to be significantly elevated in untreated porphyria cutanea tarda and in variegate porphyria.

3. Lesser elevations were seen in acute intermittent porphyria and hereditary coproporphyria. There was no elevation in erythropoietic protoporphyria.
Relation of the Extracellular [Bicarbonate]/[Chloride] Ratio to Erythrocyte Sodium Content: A Possible New Control System
Authors: Needle M. A. , Shapiro W. , Viswanathan V. , Semar M.
Published: August 2015

1. Erythrocytes were incubated in buffers with different [bicarbonate]/[chloride] ratios.

2. The erythrocyte sodium content was higher in buffers with higher [bicarbonate]/ [chloride] ratios.

3. The rise in erythrocyte sodium concentration with increase in [bicarbonate]/[chloride] ratio was independent of the effects of ouabain and ouabain plus ethacrynic acid. Primaquine-induced changes in membrane permeability, ATP depletion by starvation and the use of potassium-free buffers did not change the effect.

4. The results may demonstrate a system which either increases the permeability of erythrocytes to sodium or regulates the sodium content of erythrocytes by a carrier system which is independent of ATP.
Influence of Cortical Plasma Transit-Time on p-Aminohippurate Extraction during Induced Renal Vasodilatation in Anaesthetized Dogs
Authors: Velasquez M. T. , Notargiacomo A. V. , Cohn J. N.
Published: August 2015

1. The influence of intrarenal blood-flow distribution and plasma transit-time through the renal cortex on the reduction in p-aminohippurate (PAH) extraction (EPAH) induced by renal vasodilator agents was evaluated in anaesthetized dogs by an indicator-dilution technique.

2. Increases in renal blood flow during graded intravenous iso-osmotic saline or hyperosmotic mannitol infusions and during renal arterial infusions of acetylcholine or prostaglandin E1 were consistently associated with reduced EPAH.

3. The cortical fraction of renal blood-flow increased during vasodilatation induced by saline or acetylcholine but was unchanged during mannitol or prostaglandin infusions. Cortical blood volume (CBV) increased with saline infusion but was reduced with mannitol. Changes in CBV with acetylcholine and prostaglandin E1 were insignificant. No correlation could be found between changes in EPAH and changes in intrarenal blood flow distribution.

4. A high degree of correlation (r = 0·81) was noted between EPAH and the simultaneously determined mean cortical plasma transit-time. A significant correlation existed with pooled data for all infusions as well as with individual drug infusions.

5. We interpret these data to indicate that a shortened transit-time of plasma through the cortex, indicative of an increased velocity of cortical plasma flow, is the most important determinant of the lowering of EPAH during renal vasodilatation.
Effect of Catecholamines and other Vasoactive Substances on Superficial Hand Veins in Man
Authors: Collier J. G. , Nachev C. , Robinson B. F.
Published: August 2015

1. The direct effect of catecholamines and other vasoactive substances on superficial hand veins has been studied in man. Drugs were infused locally into the vein and changes in vein size at a constant congesting-pressure were measured by a simple optical technique.

2. Noradrenaline, adrenaline, 5-hydroxytryptamine and angiotensin II caused venoconstriction. Large doses of angiotensin II resulted in rapid development of tachyphylaxis.

3. Isoprenaline, bradykinin, acetylcholine and histamine had no effect on the relaxed vein but all caused dilatation when infused into veins preconstricted by noradrenaline or 5-hydroxytryptamine.

4. No effect of vasopressin could be demonstrated.
A Comparison of the Fat-Free Mass of Young Adults Estimated by Anthropometry, Body Density and Total Body Potassium Content
Authors: Womersley J. , Boddy K. , King Priscilla C. , Durnin J. V. G. A.
Published: August 2015

1. The fat-free mass (FFM) of ten male and ten female subjects was calculated from measurement of (i) height and weight, (ii) skinfold thickness, (iii) body density, (iv and v) total body potassium by two different methods. All the subjects were apparently healthy and in the medium range of body build and they were mainly young adults.

2. The mean FFM of the ten male subjects was similar as calculated by all methods, although comparisons between pairs of methods sometimes produced discrepancies of up to 2 kg.

3. Agreement was less good for the females but, with the exception of one of the potassium methods, still reasonable.

4. The potassium content of the FFM as mEq K/kg of FFM, was compared with the direct analysis of Forbes, Gallup & Hursh (1961) on four male cadavers. The agreement was close for the men but the K content of the FFM in women was lower than that for men. This difference is discussed.
The Co2 Titration Curve of Mixed Venous Blood
Authors: Kappagoda C. T. , Stoker J. B. , Snow H. M. , Linden R. J.
Published: August 2015

1. Simultaneous CO2 titration curves of arterial and mixed venous blood were determined in both dog and man in vivo.

2. The slopes of the CO2 titration curves of mixed venous blood were significantly less than those of the corresponding arterial curves.

3. The non-respiratory pH values of the CO2 titration curves of mixed venous blood were significantly greater than those of the corresponding arterial curves.

4. The theoretical explanations of these differences have been discussed.
Intestinal Dipeptide Transport in Normal and Cystinuric Subjects
Authors: Hellier M. D. , Holdsworth C. D. , Perrett D. , Thirumalai C.
Published: August 2015

1. The absorption of lysine and two lysine-containing dipeptides was studied in normal and cystinuric subjects by jejunal perfusion. Absorption of each dipeptide was compared with that of its constituent amino acids.

2. in normal subjects lysine was better absorbed from the dipeptide glycyl-l-lysine than from the equivalent amino acid mixture. in cystinuric patients lysine was absorbed very poorly in its free form but was absorbed normally from the dipeptide. in cystinuric patients lysine was also absorbed faster as l-lysyl-l-lysine than as free lysine.

3. During perfusion of both dipeptides significantly greater quantities of free lysine were found within the intestinal lumen in cystinuric subjects than in normal subjects. This is thought to be due to back-diffusion after hydrolysis of dipeptide by the mucosa.

4. These observations confirm the existence of dipeptide transport systems independent of those for free amino acids.
Biochemical Changes in Intestinal Mucosa after Experimental Small Bowel by-Pass in the Rat
Authors: Gleeson M. H. , Dowling R. H. , Peters T. J.
Published: August 2015

1. After experimental small bowel by-pass the excluded segment of intestine, whether jejunum or ileum, shows a decrease (expressed in units/cm of intestine) in mucosal weight, protein, RNA and activity of all eight enzymes studied (leucyl β-naphthylamidase, alkaline phosphatase, β-galactosidase, α-glucosidase, aryl sulphatase, β-glucuronidase, cytochrome oxidase and catalase). There is a fall in DNA content and there are no consistent changes in enzyme activity when expressed as units/mg of DNA.

2. The intestine remaining in continuity after small bowel by-pass shows an increase (expressed in units/cm of intestine) in mucosal weight, protein, RNA and enzyme activity. There is an accompanying rise in DNA content in the intestine in continuity.

3. The increased values of all variables measured in the intestine in continuity are much more marked in ileum than in jejunum.

4. The adaptive changes seen in the by-passed intestine and the intestine in continuity are a result of ‘hypoplasia’ and ‘hyperplasia’ respectively.
Composition of Pteroylpolyglutamates (Conjugated Folates) in Guinea-Pig Liver and Their Formation from Folic Acid
Authors: Corrocher R. , Bhuyan B. K. , Hoffbrand A. V.
Published: August 2015

1. The composition of guinea-pig liver folates and the biochemical route of formation of liver folates from injected tritium-labelled pteroylglutamic acid (folic acid) have been studied.

2. Endogenous folate was measured by microbiological assay with Lactobacillus casei and Streptococcus faecalis, with and without deconjugation of whole liver pteroylpolyglutamates (conjugated folates). Individual folate compounds were identified by microbiological assay after fractionation of liver folates by DEAE cellulose ion-exchange column chromatography.

3. Liver folate in the guinea-pig consists of about 84–87% reduced pteroylpolyglutamates with more than three glutamate moieties/molecule, about 12–15% reduced pteroyltriglutamates, about 1% reduced pteroyldiglutamates and only traces of reduced pteroylmonoglutamates.

4. About 53% of the liver folate consists of methylated derivatives.

5. Injected pteroylglutamic acid was first rapidly reduced and formylated or methylated. Glutamate moieties were then added, probably singly, to form di-, tri- and poly-glutamates. This was a relatively slow process with a hold-up at the triglutamate stage.

6. The proportion of the labelled pteroylglutamic acid in the polyglutamate form approximated to the proportion of endogenous folates in this form after 3–4 days.

7. The amount of radioactive folate in the liver increased progressively from 1 to 84 h after injection of a standard amount of radioactive pteroylglutamic acid.
The Action of L(-)-Dopa on Baroreflexes in Parkinsonism
Authors: Reid J. L. , Calne D. B. , George C. F. , Vakil S. D.
Published: August 2015

1. The intra-arterial blood pressure responses to Valsalva's manoeuvre and postural change were investigated as indices of cardiovascular reflex activity in seventeen Parkinsonian patients on maximally tolerated doses of l(-)-dopa (levodopa) and repeated in nine patients on levodopa with an extracerebral decarboxylase inhibitor, l-alpha methyldopahydrazine. The results were compared with control pretreatment responses.

2. There was significant impairment of the pressor response to Valsalva's manoeuvre on levodopa, which returned to control values after the addition of l-alpha methyldopahydrazine.

3. The systolic, diastolic and mean arterial pressures measured in a horizontal position during treatment with levodopa, with and without l-alpha methyldopahydrazine, were significantly lower than pretreatment values.

4. It is concluded that the impairment of baroreflex function by levodopa is mediated, at least in part, at the periphery. In contrast, mechanisms operating within the central nervous system contribute to the lowering of blood pressure recorded in the horizontal position in patients receiving levodopa.
Synthesis of Human Parathyroid Hormone by Cultured Cells: Evidence for Release of Prohormone by Some Adenomata
Authors: Martin T. J. , Greenberg P. B. , Michelangeli V.
Published: August 2015

1. Monolayer cultures of human parathyroid cells were established for a study of the nature of secreted human parathyroid hormone (HPTH).

2. [14C]Leucine and 75Se-labelled methionine were used as amino acid precursors for the biosynthesis of HPTH.

3. Immunoreactive labelled HPTH in the medium was extracted by affinity chromatography.

4. In cultures from glands, six adenomatous and one hyperplastic, radioactive HPTH in the media was indistinguishable in size and charge from highly purified bovine parathyroid hormone (PTH).

5. In two cultures from adenomata, media contained an immunoreactive basic peptide resembling ‘pro-PTH’ in its electrophoretic behaviour. The freeze-dried cells contained the same basic peptide.
Iron Metabolism after Renal Transplantation
Authors: Boddy K. , Will G. , Lawson D. H. , King Priscilla C. , Linton A. L.
Published: August 2015

1. The oral absorption and the rate of loss from the body of radioactive iron were measured by whole-body monitoring in patients with functioning renal homografts. The incorporation of radioactive iron into erythrocytes was also measured.

2. The results were compared with corresponding values in normal subjects and in non-dialysed and dialysed patients with chronic renal failure.

3. The mean oral absorption and incorporation into erythrocytes of radioactive iron was intermediate between that of normal subjects and of both non-dialysed and dialysed patients with chronic renal failure.

4. The mean rate of loss from the body was not significantly different from that in normal subjects and non-dialysed patients with chronic renal failure but it was significantly less than that in dialysed patients.
Changes in Glomerular Filtration Rate during Long-Term Treatment with Propranolol in Patients with Arterial Hypertension
Authors: Ibsen H. , Sederberg-Olsen P.
Published: August 2015

1. Glomerular filtration rate was determined from 51Cr—EDTA clearance in twenty hypertensive subjects treated with propranolol.

2. A significant mean decrease of 13% in the glomerular filtration rate was found during treatment, and an increase of the same order of magnitude after withdrawal of propranolol.

3. It is suggested that these changes are related to a reduction in the renal blood flow.

4. No significant changes were found in plasma volume.