bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of Renal Beta- and Alpha-Adrenergic Stimulation on Proximal Sodium Reabsorption in Dogs
Authors: Blendis L. M. , Auld R. B. , Alexander E. A. , Levinsky N. G.
Published: August 2015

1. Micropuncture studies were performed in dogs to evaluate more directly the suggestion from clearance experiments that alpha-adrenergic stimulation enhances and beta-adrenergic stimulation depresses proximal sodium reabsorption. Experiments were performed during unilateral renal artery infusion of the appropriate drugs in the doses used in previous clearance studies.

2. To study pure beta stimulation, collections were made during alpha blockade with phenoxybenzamine and re-collections during the addition of beta stimulation with isoproterenol. No significant changes were noted in the ratio of inulin concentrations in tubular fluid and plasma (TF/P)In (1·49 ± 0·04 to 1·52 ± 0·05), absolute sodium reabsorption (23 ± 1 to 23 ± 3 nl/min), single nephron glomerular filtration rate (SNGFR) (75 ± 7 to 76 ± 15 nl/min) and the ratio of SNGFR to inulin clearance (SNGFR/CIn) × (106), (2·95 ± 0·4 to 2·65 ± 0·4).

3. To study pure alpha-adrenergic stimulation, collections were made during beta blockade with propranolol and again during the addition of alpha-adrenergic stimulation with nor-adrenaline. There were no significant changes in (TF/P)In (1·50 ± 0·09 to 1·42 ± 0·04), absolute sodium reabsorption (25 ± 7 to 17 ± 4 nl/min), SNGFR (68 ± 13 to 58 ± 10 nl/min) or SNGFR/CIn(× 106) (2·76 ± 0·6 to 2·51 ± 0·5).

4. CIn increased slightly after beta but not after alpha stimulations. p-Aminohippuric acid clearance (CPAH) and urine sodium excretion (UNaV) were not significantly different in either set of studies.

5. We conclude that neither alpha not beta adrenergic stimulation has a significant effect on proximal sodium reabsorption when infused in doses that do not alter renal haemodynamics.
Turnover Studies of Copper in Homozygotes and Heterozygotes for Wilson's Disease and Controls: Isotope Tracer Studies with 67Cu
Authors: Strickland G. T. , Beckner W. M. , Leu Mei-Ling , O'Reilly S.
Published: August 2015

1. Studies with 67Cu were carried out on thirteen patients with Wilson's disease (WD), twenty-nine of their parents and siblings, thirteen normal subjects and seven subjects with cirrhosis of the liver. Control subjects and five siblings of patients with WD generally excreted more than 15% of the dose of 67Cu in their 5-day stool collections, had normal liver/thigh radioactivity ratio patterns, and had whole-body biological 67Cu half-times of less than 40 days. The remaining twenty-four family members, including all twelve parents, and the patients with WD generally excreted less than 15% of the dose of 67Cu in their 5-day stool collections, had abnormal liver/thigh radioactivity ratio patterns, and had whole-body biological 67Cu half-times greater than 40 days.

2. The data demonstrate a normal 67Cu biological half-time of 28 days and faecal excretion of 22% in 5 days, and suggest a decreased biliary excretion of copper in both homozygous and heterozygous individuals with WD.
Absorption of Copper in Homozygotes and Heterozygotes for Wilson's Disease and Controls: Isotope Tracer Studies with 67Cu and 64Cu
Authors: Strickland G. T. , Beckner W. M. , Leu Mei-Ling
Published: August 2015

1. Absorption of copper was determined by the simultaneous administration of 64Cu orally and 67Cu intravenously to six patients with Wilson's disease (WD), eighteen of their parents and siblings, four normal subjects and three subjects with cirrhosis of the liver. Absorption was calculated by three methods: (1) the mean ratio of 64Cu to 67Cu body retention at 3 and 4 days as determined by whole-body counting; (2) the mean ratio of 64Cu to 67Cu at 3 and 4 days as determined by faecal excretion; and (3) the mean ratio of 64Cu to 67Cu plasma radioactivity 6–24 h after administration.

2. The total-body counting and faecal methods for determining copper absorption agreed with each other, demonstrating that the normal absorption of copper is 40–70% (mean 56%) of the dose and that absorption is not influenced by cirrhosis of the liver, age or sex; but it appears to be inversely related to the amount of carrier copper. The absorption of copper in both homozygotes and heterozygotes for WD did not differ significantly from that of the control subjects. Therefore, the increased body burden of copper in WD does not appear to be due to over absorption, but rather to decreased biliary excretion of copper.
Changes in total Body Calcium Content in Primary Hyperparathyroidism
Authors: Hosking D. J. , Chamberlain M. J. , Fremlin J. H.
Published: August 2015

1. The change in total body calcium content after surgery for primary hyperparathyroidism was studied in seven patients by whole body neutron activation analysis. Three patients who remained in the uncontrolled state for up to 12 months were also studied by this technique.

2. The technique and its reproducibility are described. Changes in total body calcium greater than ±4% should be detectable using this method.

3. The change in total body calcium after surgery was variable. Total body calcium content decreased in three cases after apparently successful parathyroidectomy. Not all the cases experiencing an increase in body calcium content had radiological evidence of bone disease.

4. The role of relative hypoparathyroidism due to suppression of normal parathyroid tissue by a functioning adenoma is discussed.
Leucocyte Potassium in Uraemia: Comparisons with Erythrocyte Potassium and Total Exchangeable Potassium
Authors: Patrick J. , Jones N. F. , Bradford Berenice , Gaunt Judith
Published: August 2015

1. The potassium status of uraemic patients was assessed by measurements of leucocyte potassium, erythrocyte potassium, exchangeable potassium (42K) and total body water (3H). The difficulties involved in assessment of exchangeable potassium and whole body potassium are discussed, and the advantages of the leucocyte as a model for the study of intracellular potassium are described.

2. in twenty-three measurements in sixteen undialysed uraemic patients, two patterns of reduction in intracellular potassium concentrations could be discerned in the leucocyte: (a) due to reduction in potassium related to cell solids; (b) due to an increase in cell water. Both abnormalities were present in some patients.

3. Similar measurements were made in eighteen uraemic patients receiving regular haemodialysis against dialysis fluid with a potassium concentration of 1 mmol/l. in this group leucocyte potassium did not differ significantly from normal, while leucocyte water content was slightly less than normal.

4. It is concluded that disturbances of leucocyte water and potassium are common in advanced uraemia, and that these functions tend towards normal during regular dialysis using dialysis fluid with a low potassium content.
A New Method for Measuring Static Compliance in Infants and Young Children
Authors: Milner A. D. , Hull D. , Hatch D. J. , Cogswell J. J.
Published: August 2015

1. A new method for measuring static compliance, which does not require general anaesthesia or a leak-free airway, is described for infants and young children.

2. Thoracic volume changes produced by static inflation pressures are measured by a respiratory jacket, and results compare well with those obtained by the syringe-inflation method.

3. This method can be used in the intensive care of sick infants, where it allows a new approach to the investigation of lung mechanics.
The Effect of Parathyroid Hormone on the Uptake and Release of Calcium by Bone in Tissue Culture
Authors: Robertson W. G. , Peacock M. , Atkins D. , Webster L. A.
Published: August 2015

1. Bovine parathyroid hormone at a concentration of 1 unit/ml caused an immediate transient uptake of calcium from the bathing medium by 5-day-old mouse calvaria in tissue culture.

2. The uptake of calcium by bone was followed by the release of calcium into the medium over the subsequent 3–4 h.

3. The results support the conclusion that the primary action of the hormone on calcium transport in bone is to cause an increase in the intracellular concentration of calcium before producing the characteristic release of calcium from bone.
Subcellular Localization of Folate and Effect of Methotrexate on the Incorporation of Radioactive Folic Acid into Guinea-Pig Liver Folate
Authors: Corrocher R. , Hoffbrand A. V.
Published: August 2015

1. The subcellular distribution of endogenous folate and of injected [3H]folic acid has been studied in guinea-pig liver.

2. Endogenous folate was found to be concentrated in the mitochondrial and cell-sap fractions.

3. At 1 h after injection, labelled folic acid (pteroylglutamic acid) was concentrated in the microsomes (where it is possibly reduced to tetrahydrofolic acid).

4. At all subsequent times after injection of labelled pteroylglutamic acid (4, 24 and 84 h) radioactivity was concentrated in mitochondria and cell sap and it is, therefore, likely that conjugation of glutamates to form pteroylpolyglutamates occurs in one or both of these subcellular fractions in mammalian cells.

5. Methotrexate-treated animals converted at least some labelled pteroylglutamic acid into non-reduced pteroyl di-, tri- and poly-glutamic acids by 4 h after the injection.

6. Reduction of pteroylglutamic acid is, therefore, not essential for pteroylpolyglutamate formation in liver cells.

7. Methotrexate blocks the reduction of pteroyl di-, tri- and poly-glutamic acids, as well as of pteroylglutamic acid.
Ventilatory Response to Exercise and to Co2 Rebreathing in Normal Subjects
Authors: Rebuck A. S. , Jones N. L. , Campbell E. J. M.
Published: August 2015

1. Changes in ventilation during progressive exercise were measured in eleven normal subjects. Ventilatory response to carbon dioxide at rest was measured in the same subjects using a rebreathing method.

2. The range of ventilatory response to exercise was 16·6–32·0 litres min−1 (litres CO2 min−1)−1 (mean 22·7; SD 5·35); response to O2 uptake was 17·0–43·9 litres min−1 (litres O2 min−1)−1 (mean 29·02; SD 9·07). Ventilatory response to CO2 (Sco2) ranged from 0·81 to 3·22 litre min−1 mmHg−1 (mean 1·87; SD 0·62).

3. There was a highly significant (P < 0·001) correlation between the changes in response to increasing CO2 output or O2 uptake, and Sco2.

4. The results are compatible with the suggestion that ventilation during exercise in normal subjects is directly related to their chemosensitivity to CO2, those having the highest sensitivity showing the greatest exercise ventilation.
Bronchial Sympathetic Activity in Chronic Bronchitis
Authors: Astin T. W.
Published: August 2015

1. Measurements of airways resistance and lung volume were made in sixteen patients with chronic bronchitis and ten patients without chest disease before and after intravenous propranolol administration.

2. The airways resistance of the patients with chronic bronchitis increased significantly after propranolol administration but in the control subjects there was no significant increase.

3. In the patients with chronic bronchitis the increases in airways resistance were greater when the initial values were high.

4. In seven of the patients with chronic bronchitis and seven further control subjects airways resistance was measured before and after intravenous thymoxamine administration.

5. The airways resistance of the normal subjects was unchanged by thymoxamine administration, but that of the patients with chronic bronchitis decreased significantly.

6. The results are consistent with the existence of bronchial alpha receptors in man. In patients with chronic bronchitis there are greater degrees of both alpha and beta bronchial sympathetic activity than in normal subjects. The greater the severity of the condition the greater is the degree of beta sympathetic activity. In considering the factors causing airways obstruction in chronic bronchitis sympathetic activity should be taken into account.
A Study of Water and Electrolyte Transport by the Excluded Human Colon
Authors: Bown R. L. , Sladen G. E. , Rousseau B. , Gibson J. A. , Clark M. L. , Dawson A. M.
Published: August 2015

1. Four subjects with colonic exclusion for chronic hepatic encephalopathy were investigated by a perfusion technique in a study of water and electrolyte transport by the colon.

2. The mean values for water and electrolyte transport, mucosal potential difference and colonic volume compare closely with values previously obtained in the intact human colon.

3. A reduction in luminal pH did not affect water or sodium absorption, in contrast with previous animal studies, but did increase chloride absorption, probably on the basis of increased chloride-bicarbonate exchange.

4. Potassium secretion increased with a reduction in luminal pH, possibly as a result of the low pH increasing mucosal permeability.

5. It is concluded that the excluded colon in these patients provides a valid model for studies of normal colonic physiology.
Plasma Volume, Extracellular Fluid Volume and Exchangeable Sodium Concentrations in the New Zealand Strain of Genetically Hypertensive Rat
Authors: Gresson C. R. , Bird D. L. , Simpson F. O.
Published: August 2015

1. Rats of the New Zealand strain with genetic hypertension (GH rats) were found to have lower plasma volume in relation to body weight than rats of the normotensive parent strain (N rats). GH rats had higher venous packed-cell volume percentage than N rats, but total erythrocyte volume was similar in the two strains of rats. Extracellular fluid volume and exchangeable sodium concentrations were lower in the GH rats. Plasma sodium concentration was not altered; plasma potassium concentration was slightly higher in the GH rats.

2. These results indicate that hypersecretion of a sodium-retaining hormone is unlikely to be a primary factor causing hypertension in the GH rats. Cardiac output has not been measured: if an increased cardiac output is a factor in the maintenance of the hypertension, it is evidently not secondary to an increased blood volume.

3. The lower exchangeable sodium concentrations and body fluid volumes found in the GH rats may be due to lower aldosterone activity secondary to a decrease in the activity of the renin-angiotensin system, or to the effects of the elevated blood pressure on the renal handling of sodium, or to both factors.
Chloride Titration in the Dog: The Influence of Extracellular Fluid Expansion on the Pattern of Chloride Reabsorption
Authors: Cohen J. J. , Bar-Khayim Y. , Garella S. , Chazan J. A.
Published: August 2015

1. The technique of chloride titration was employed in twenty dogs to determine the pattern of renal chloride handling in response to systematic increases in filtered chloride load. The influence of variations in sodium reabsorption on this pattern was also assessed by producing a wide spectrum of volume expansion during the titration protocols.

2. The results indicate that chloride reabsorption is proportional both to the rate of chloride filtration and to the rate of sodium reabsorption and, hence, that the specific pattern of each chloride titration curve is the fortuitous consequence of the interplay between these two factors.

3. The rate of chloride reabsorption relative to the simultaneous rate of sodium reabsorption was used as an index of the ability of the kidney to maintain chloride homeostasis and indicated that the kidney invariably tends to return depressed. plasma chloride concentration towards normal but, under the conditions of these acute experiments, consistently tends to reduce elevated plasma chloride concentration only when cation reabsorption is markedly depressed.

4. The present observations do not elucidate the mechanism responsible for these findings but suggest that plasma chloride concentration is not regulated through the operation of a threshold mechanism.
Plasma Catecholamine and Dopamine β-Hydroxylase Amounts in Phaeochromocytoma
Authors: Geffen L. B. , Rush R. A. , Louis W. J. , Doyle A. E.
Published: August 2015

1. Plasma catecholamine and dopamine β-hydroxylase (DβH) amounts were measured in a series of patients with proven phaeochromocytoma and compared with those of a group with essential hypertension.

2. Circulating catecholamine amounts were greatly elevated in phaeochromocytoma but plasma DβH was not significantly raised.

3. There was a significant correlation between plasma noradrenaline and DβH in individuals with essential hypertension but not with phaeochromocytoma.

4. The relative deficiency of DβH secretion in phaeochromocytoma indicates that the mechanism of release of catecholamines from these tumours does not involve the normal exocytosis of catecholamine storage vesicles. This supports the hypothesis that the primary defect responsible for the hypertension is excessive synthesis of catecholamines that bypass the normal storage and secretion mechanisms and diffuse into the circulation.
Polymeric Collagen of Skin in Normal Subjects and in Patients with Inherited Connective Tissue Disorders
Authors: Francis M. J. O. , Smith R. , Macmillan D. C.
Published: August 2015

1. The major collagen fraction of skin, which in vivo consists of tropocollagen molecules aggregated into extracellular fibres, has been extracted from forty-nine normal subjects and nineteen patients with inherited and acquired disorders of connective tissue.

2. In normal subjects the chemical stability of this fraction progressively increased up to the age of 60.

3. This fraction was less stable than normal in patients with homocystinuria, Werner's syndrome, myositis ossificans progressiva, pseudoxanthoma elasticum, juvenile osteoporosis and acromegaly.

4. In osteogenesis imperfecta (OI) the stability of this fraction was normal in those patients with markedly blue sclerae, although the amount which could be extracted from the skin was low: opposite results were found in those OI patients with sclerae of normal colour.

5. This study provides preliminary evidence of collagen abnormality in several heritable disorders of connective tissue.
Conversion of Angiotensin I into Angiotensin II in the Isolated Perfused Rat Kidney
Authors: Hofbauer K. G. , Zschiedrich H. , Rauh W. , Gross F.
Published: August 2015

1. In the isolated rat kidney, perfused at constant pressure with a medium free from renin substrate, addition of angiotensin I to the perfusate decreases renal ‘plasma’ flow.

2. A peptide inhibitor, SQ 20881, of converting enzyme reduces the vasoconstrictor effect of angiotensin I up to a maximum of 87%, the degree of inhibition being dose-dependent.

3. The molar, ratio of equi-effective doses of angiotensin I and angiotensin II was 50:1, indicating a low rate of intrarenal conversion of the decapeptide.

4. The vasoconstrictor effect elicited by the addition of renin substrate to the perfusate was not inhibited by SQ 20881, even if the concentration was fifteen times that which produced the maximum inhibition of conversion of angiotensin I.
Forearm Blood Flow during and after Isometric Hand-Grip Contractions
Authors: Mottram R. F.
Published: August 2015

1. A method is described for the measurement of forearm blood flow during sustained voluntary isometric hand-grip contractions that can be maintained constant by the subject's monitoring of the strength of his contractions.

2. In most subjects it was found that contractions of 5% of their maximal voluntary force could be maintained without fatigue, and without any post-exercise increase in blood flow. More powerful contractions produced both fatigue and a large post-exercise hyperaemia, even though blood flow had reached a plateau during the exercise.

3. An attempt to show that the post-exercise hyperaemia was a response to a steadily accumulating ‘metabolic vasodilator stimulus’ and varied directly in size with the duration of the contraction gave equivocal results.

4. Ischaemic pain in the hand was not the cause of the post-exercise hyperaemia.
Renal Function in Chronic Intravascular Haemolysis Associated with Prosthetic Cardiac Valves
Authors: Slater S. D. , Rahman M. , Lindsay R. M.
Published: August 2015

1. Glomerular nitration, wate rconcentration and acid load tests, measurement of urinary protein and cell excretion rates, bacteriological examination of the urine, and analysis of the urinary amino acid content were carried out in eight patients with chronic intravascular haemolysis due to aortic valve replacement.

2. All results were normal except for a slight reduction in creatinine clearance rate in two patients and a slight elevation of urinary protein in a third; these abnormalities were considered of doubtful significance.

3. It is concluded that chronic intravascular haemolysis with its consequent renal haemosiderosis appears not to interfere with renal function.
The Effect of Local Anaesthesia of the Airway on Respiratory Reflexes in the Rabbit
Authors: Jain S. K. , Trenchard Diana , Reynolds Felicity , Noble M. I. M. , Guz A.
Published: August 2015

1. The effect of breathing anaesthetic aerosols (lignocaine 20% and bupivacaine 5%) on respiratory reflexes was studied in rabbits.

2. The cough reflex was blocked in every experiment.

3. The inflation reflex was abolished in eleven out of twenty-six rabbits given lignocaine aerosol and in fourteen out of fifteen rabbits given bupivacaine aerosol.

4. The deflation reflex was blocked pari passu with the inflation reflex.

5. The ventilatory response to histamine was sometimes blocked; more commonly it was partially preserved.

6. The ventilatory response to phenyldiguanide was never impaired and often enhanced.

7. Bronchoconstriction produced by electrical stimulation of the peripheral cut ends of the cervical vagus nerves was unaffected.

8. Block of the above respiratory reflexes was associated with slower, deeper breathing.

9. Bupivacaine has produced more consistent and reliable results than lignocaine; the effects were reversible in both cases usually within 30 min.

10. Plasma concentrations of both anaesthetics were usually below the generally accepted toxic concentrations in man.

11. Control experiments using intravenous infusions of the anaesthetics proved that none of the effects could have been produced by systemic effects of the absorbed anaesthetic.

12. No pathological changes were found in the airways on both macroscopic and microscopic examination.

13. The experiments show that it is possible to block respiratory reflexes whose afferents arise from the airways, and to preserve a reflex arising at alveolar level.
Iron-Deficiency Anaemia: Its Effect on Maximum Aerobic Power and Responses to Exercise in African Males Aged 17–40 Years
Authors: Davies C. T. M. , Chukweumeka A. C. , Van Haaren J. P. M.
Published: August 2015

1. The physiological responses to exercise of two groups of industrial workers with moderate and severe anaemia were measured and compared with a group of matched controls, working and living under similar conditions. Exercise was performed on a stationary bicycle ergometer at five consecutive work loads. During the final minute of each exercise periods, oxygen intake, minute ventilation volume, and cardiac and respiratory frequencies were measured. On a separate occasion, blood haemoglobin concentration was measured at rest and cardiac output and blood and plasma volumes were estimated while subjects exercised at a fixed percentage of the maximum aerobic power for 6 min.

2. Oxygen intake for a given work load and ventilation rate was similar in all subjects studied but exercise cardiac output was elevated in the anaemic group. The increased cardiac output was due to an increased heart rate, the stroke volume being similar in the anaemic and control subjects. There was a marked decrement (∼34%) in maximum aerobic power and some evidence of a raised plasma volume in the severely anaemic group.

3. These results suggest that anaemia impairs performance during moderate and near maximum exercise. There is an associated rise of cardiac output and plasma volume.
Sites of Maximal Absorption and Hydrolysis of Two Dipeptides by Rat Small Intestine in Vivo
Authors: Crampton R. F. , Lis Maria T. , Matthews D. M.
Published: August 2015

1. Though mucosal uptake of peptides plays an important part in protein absorption, little is known about the site of maximal absorption of peptides in the small intestine. This paper reports an investigation of the characteristics of absorption and hydrolysis of l-methionyl-l-methionine (Met-Met) and glycylglycine (Gly-Gly) by tied loops along the length of the small intestine of the rat, and those of absorption of the equivalent l-methionine (Met) and glycine (Gly).

2. Absorption of Met-Met, or a mixture of Met-Met and Met, was maximal in the proximal half of the small intestine, whereas absorption of Met was maximal in the distal half. Absorption of Met-Met was greater than that of the equivalent Met, especially in the proximal small intestine. In most sites, absorption of a mixture of Met-Met and Met was not significantly different from that of the equivalent Met-Met. Absorption of Met was not increased by raising its concentration from 100 to 200 μmol/ml, but addition of Met-Met (50 μmol/ml) produced a large increase in absorption, indicating that absorption of Met from Met-Met is independent of that from free Met. During absorption of Met-Met, large amounts of free Met appeared in the intestinal lumen. Most of this resulted from intralumen hydrolysis. The hydrolytic ability of mucosal homogenates was several times greater than that required to hydrolyse the Met-Met disappearing from the lumen during absorption.

3. The sites of maximal absorption of Gly-Gly, Gly and a mixture of Gly-Gly and Gly, were all in the proximal half of the intestine near the mid-point. Absorption of Gly-Gly was greater than that of the equivalent Gly, especially in the proximal sites. In several sites, there was no significant difference between absorption of a mixture of Gly-Gly and Gly and that of the equivalent Gly-Gly. During absorption of Gly-Gly, the amounts of free Gly appearing in the lumen were small except in the two most distal sites. Most of the free Gly resulted from back-diffusion from the mucosa. The hydrolytic ability of mucosal homogenates was barely adequate to hydrolyse the Gly-Gly disappearing from the lumen during absorption.

4. The results suggest that there is no real discrepancy between the site of maximal absorption of protein digestion products from tied loops of small intestine and that of their absorption in the intact animal. They indicate that absorption of Met and Met-Met involves independent mechanisms, and confirm previous evidence that the capacity of the intestine to absorb mixtures of peptides and amino acids is greater than its capacity to absorb amino acids alone.
Protective Effect of Frusemide in Acute Tubular Necrosis and Acute Renal Failure
Authors: Bailey R. R. , Natale R. , Turnbull D. I. , Linton A. L.
Published: August 2015

1. Acute tubular necrosis (ATN) with acute renal failure (ARF) was induced in rats with (a) a combination of subcutaneous (s.c.) cephaloridine 500 mg/kg, frusemide 50 mg/kg and 4 ml/kg of 50% (v/v) glycerol in sterile water, (b) s.c. cephaloridine 1500 mg/kg, (c) s.c. mercuric chloride 2·0 and 4·7 mg/kg and (d) both s.c. and intramuscular glycerol (10 ml/kg in sterile water).

2. Pretreatment of rats with varying doses of frusemide protected against both the ATN and ARF of all the models except for glycerol where the ATN and ARF was aggravated. The protection against the ATN of cephaloridine alone and the ATN and ARF of the cephaloridine-glycerol-frusemide combination was almost complete if the last (or only) frusemide pretreatment injection was given 5–12 h before the challenge. Frusemide administered together with cephaloridine makes the ATN and ARF more severe.

3. The pretreatment regime results in moderate dehydration, a lowered serum potassium, a markedly elevated plasma renin activity and a reduced glomerular filtration rate. All these factors would be expected to increase the damage resulting from the nephrotoxic challenges, rather than to protect against it.

4. The possible mechanism of this protection conferred by frusemide pretreatment on the ‘toxic’ type of ARF is discussed. With this type of nephrotoxic insult the resulting ATN involves mainly the proximal convoluted tubules. The potentiation of the ‘circulatory’ type of ARF by frusemide pretreatment probably results from the effects of dehydration.
The Ventilatory Response to Hypoxia during Exercise in Cyanotic Congenital Heart Disease
Authors: Taylor M. R. H.
Published: August 2015

1. In contrast to the diminished ventilatory response to hypoxia which has been found at rest in cyanotic congenital heart disease, hyperventilation was noted on exercise in children who were cyanosed.

2. Sixteen children had low arterial oxygen saturations on exercise and thirteen of these hyperventilated by an amount similar to that reported in normal adults breathing hypoxic gas mixtures.

3. The three children who had little ventilatory response in relation to the increase of hypoxia during exercise all had a triad of long-standing cyanosis starting early in life, high haemoglobin concentration and low arterial oxygen saturation at rest in air.
Oxygen Consumption in Children with Congenital Diseases of the Heart
Authors: Kappagoda C. T. , Greenwood P. , Macartney F. J. , Linden R. J.
Published: August 2015

1. An open-circuit method for the measurement of oxygen consumption in children which is suitable for use during cardiac catheterization has been described.

2. Since it has been previously shown that there is no systematic error in this method, the accuracy of the method is described by the random error (i.e. reproducibility). The reproducibility of the method has been determined by the repeated measurement of oxygen consumption in children with congenital diseases of the heart under specified ‘standard’ conditions.

3. A simple method of predicting the oxygen consumption in these children was devised by subjecting the data to a multivariate regression analysis.

4. It is concluded that the accuracy of these predictions, although considerably better than that in the published literature, is not good enough to merit its use in the routine haemodynamic assessment.
Studies on Hypertension in Spontaneously Hypertensive Rats
Authors: Okamoto Kozo , Yamori Yukio , Nosaka Shoichiro , Ooshima Akira , Hazama Fumitada
Published: August 2015

1. The pathogenesis and complications occurring in spontaneously hypertensive rats (SHR) have been studied.

2. Genetic factors are important both in the development of hypertension and in determining susceptibility to vascular lesions.

3. Selective substrains of SHR may be particularly prone to develop cerebrovascular lesions.
Effect of Low-Density Lipoprotein Preparations on Plasmin
Authors: Herbert Robyn J. , Bennett B. , Ogston D.
Published: August 2015

1. Crude preparations of β-lipoprotein inhibited the fibrinolytic and caseinolytic activity of plasmin: they were contaminated by α2-macroglobulin and α1-antitrypsin, known inhibitors of plasmin.

2. Purified β-lipoprotein, free from α2-macroglobulin and α1-antitrypsin, did not inhibit plasmin. It is concluded that β-lipoprotein does not have antiplasmin properties.
Studies on the New Zealand Strain of Genetically Hypertensive Rats
Authors: Simpson F. O. , Phelan E. L. , Clark D. W. J. , Jones D. R. , Gresson C. R. , Lee D. R. , Bird D. L.
Published: August 2015

1. The New Zealand strain of rats with genetic hypertension (GH rats), the Japanese strain with spontaneous hypertension and the salt-sensitive strain of Dahl are now well established as three genetically pure lines for use in hypertensive research. Other pure lines not consciously selected for high blood pressure have also recently been shown to exhibit hypertension.

2. In the GH rats the inheritance of the blood pressure appears to be polygenic; thus a simple causation of the hypertension appears unlikely. The inheritance is also complex in the other pure lines of hypertensive rats.

3. In the GH rats variation in intake of sodium from 0.05% to 1% of the solid diet does not affect the development of the hypertension.

4. The renin-angiotensin-aldosterone system does not appear to play a primary role in the initiation of the hypertension in the GH rats. Compared with normotensive rats of the parent colony, plasma and renal renin are decreased, total exchangeable and carcass sodium are decreased, as are also the plasma volume and total extracellular fluid volume. Plasma sodium is normal and plasma potassium increased.

5. There is no evidence of a primary abnormality of catecholamine storage or turnover. Prevention of the development of the sympathetic nervous system from birth does not entirely abolish the difference in blood pressure between GH rats and comparably treated normotensive rats.

6. The increased peripheral resistance in blood-perfused hind limbs and tails of GH rats is due both to increased neurogenic and myogenic components and to a structural element. Increased vascular reactivity to a variety of constrictor agents is readily demonstrated in saline-perfused preparations.

7. The different strains of hypertensive rats may in their diversity mirror the differences between the various forms of human essential hypertension.
Plasma Volume Decrease and Elevated Evans Blue Disappearance Rate in Essential Hypertension
Authors: Ulrych Milos
Published: August 2015

1. The disappearance rate of intravenously injected Evans Blue, plasma volume, cardiac output, and blood pressure were measured in seven normotensive and eighteen hypertensive subjects.

2. Plasma volume was found to be negatively correlated with the mean arterial pressure, Evans Blue disappearance rate and packed cell volume.

3. Faster disappearance rate of Evans Blue in hypertensive subjects may be due to an abnormality of mixing of the label or of the capillaries.
The Inactivation by Carbenoxolone of Individual Human Pepsinogens and Pepsins
Authors: Roberts N. B. , Taylor W. H.
Published: August 2015

1. Carbenoxolone, in suspension at pH 4·0, inhibits swine pepsin A, and human pepsins 1, 3 and 5. Human pepsin 5 is the most readily inhibited, and human pepsin 1 the least.

2. Inhibition occurs by a process which is time-dependent, temperature-dependent and proportional to the quantity of carbenoxolone suspended.

3. Carbenoxolone, in solution at pH 7·4 and pH 8·0, inhibits the activation of the total pepsinogens of human gastric mucosal extracts and of the individual pepsinogens 1, 3 and 5. Pepsinogen 1 was the most readily inhibited, pepsinogen 5 the least.

4. Chymotrypsin was readily inhibited by carbenoxolone at pH 7·4 and 8·0. Trypsin was not inhibited at pH 7·4 but was inhibited, relatively weakly, at pH 8·0. Pronase was weakly inhibited at pH 7·4 and 8·0 but papain was weakly activated.

5. Carbenoxolone is therefore not a general enzyme inhibitor but shows specificity for enzymes (pepsins and chymotrypsin) which split proteins at the same bonds, rather than for enzymes with similar active centres (chymotrypsin and trypsin).

6. The results suggest that, in vivo, carbenoxolone might diminish peptic activity in three ways: by inactivating pepsinogens irreversibly in the mucosal cells or at some point before their activation to pepsins; by inhibiting pepsins irreversibly in the gastric lumen; and by binding pepsins in the lumen without destroying their activity but decreasing their effective concentration.

7. These results are compatible with the hypothesis that pepsins, and pepsin 1 particularly, are factors in the aetiology of peptic ulcer.
Retention of a Single Oral Massive Dose of Vitamin A
Authors: Pereira Sheila M. , Begum Almas
Published: August 2015

1. Six pre-school children with normal intestinal absorption were given 100000 μg of retinyl palmitate and 14·4 μCi of [11,12-3H]retinyl acetate.

2. The absorption, excretion and retention of the label were determined.

3. The children retained 23–54% of the label.

4. The inefficacy of the massive dose as a prophylaxis against deficiency is discussed.
Maximum Motor Nerve Conduction Velocity in XYY Males
Authors: Wright M. O.
Published: August 2015

1. Maximum motor nerve conduction velocities were determined under standard conditions for the median and ulnar nerves in the right forearm in males: (a) from the general population, (b) from a subnormality hospital, and (c) in males with the XYY sex chromosome abnormality. Distal latencies for these nerves were also measured.

2. No significant differences in maximum peripheral motor nerve conduction were found between the two control populations from the general population and from the subnormality hospital.

3. The maximum motor conduction velocity in the median nerve in the XYY group was significantly slowed when compared with both control groups. In the case of the ulnar nerve, maximum motor conduction was significantly slowed when compared with the general population, but not when compared with the subnormality hospital group.

4. There were no significant differences in the mean distal latencies of either the median or ulnar nerves between the two control groups.

5. In the XYY group, the distal latency in the ulnar nerve was significantly prolonged when compared with both control groups. In the case of the median nerve, the distal latency was prolonged significantly when compared with the general population; when the comparison was made with the subnormality hospital group significant prolongation was also observed but was less marked.
The Respiratory Response to Chronic Metabolic Alkalosis and Acidosis in Disease
Authors: van Ypersele de Strihou C. , Frans A.
Published: August 2015

1. The respiratory response to chronic metabolic alkalosis was defined on the basis of 182 determinations of the arterial blood pH, Pco2, HCO3− concentration and Po2 obtained in thirty uraemic patients undergoing chronic haemodialysis. Plasma bicarbonate concentrations, [HCO3−], ranged from 20 to 38 mmol/l before dialysis, and were elevated by increasing the acetate content of the dialysate.

2. The calculated arterial carbon dioxide tension (Pa,co2) was linearly related to HCO3−, Pa,co2 reaching 50 mmHg at a [HCO3−] of 37.5 mmol/l. This response was virtually identical with that previously reported in chronic metabolic acidosis. The 95% confidence limits of the respiratory adaptation to chronic metabolic acid-base disorders were calculated for [HCO3−] ranging from 11 to 38 mmol/l.

3. Analysis of the individual response lines of thirteen patients revealed no difference among their slopes but significant differences among their elevations. Each subject appears thus to have his own threshold to acid-base stimuli.

4. Hypoxaemia developed with increasing [HCO3−], Pa,o2 falling in a curvilinear fashion to reach 70 mmHg at a [HCO3−] of 37.5 mmol/l.
Studies on the Pathogenesis of Fever in Renal Carcinoma
Authors: Cranston W. I. , Luff R. H. , Owen D. , Rawlins M. D.
Published: August 2015

1. Endogenous pyrogen (EP) was detected in tumour extracts from four patients with renal carcinoma and fever. No EP was detected in extracts of tumours from six afebrile patients or in extracts of normal kidney.

2. Tumour slices from one febrile patient released EP into a nutrient incubation medium; this process was suppressed by the presence of cycloheximide. Tumour slices from an afebrile patient did not release EP on incubation.

3. Leucocytes from the peripheral blood of two febrile patients with renal carcinoma did not yield EP on incubation in saline.

4. The production of EP by leucocytes ‘activated’ by 2 h incubation with a Proteus endotoxin was not inhibited by cycloheximide.

5. It is suggested that fever associated with renal carcinoma is caused by the release of EP within the tumour.
The Effect of Ethanol on the Cough Reflex
Authors: Berkowitz H. , Reichel J. , Shim C.
Published: August 2015

1. Coughing was induced in ten healthy subjects with various threshold concentrations of nebulized citric acid. The citric acid aerosol method of cough induction proved a reliable and reproducible tool for assessing the cough threshold in an individual. The subjects were retested after consumption of 1 ml of ethanol/kg body weight. Coughing was significantly suppressed in nine of the ten subjects.

2. The marked suppression of the cough reflex by the moderate amounts of ethanol used in this study provides confirmatory evidence for the suspected causal links between ethanol abuse and certain pulmonary infections caused by aspiration.
The Effect of Simulated Metabolic Acidosis on Intracellular pH and Lactate Metabolism in the Isolated Perfused Rat Liver
Authors: Lloyd M. H. , Iles R. A. , Simpson B. R. , Strunin J. M. , Layton J. M. , Cohen R. D.
Published: August 2015

1. The relationship between extracellular pH (pHe), intracellular pH (pHi) and lactate uptake was studied in the isolated perfused rat liver during simulated metabolic acidosis.

2. pHi fell to a considerably less extent than pHe when the latter was decreased from pH 7·4 to 6·7.

3. The liver took up lactate when pHi was greater than 7·0; at lower values of pHi lactate output occurred.

4. The relevance of these observations to the control of hepatic pHi and lactate metabolism is discussed.
Plasma Lipid and Lipoprotein Abnormalities in Patients with Malabsorption
Authors: Thompson Gilbert R. , Miller J. Paul
Published: August 2015

1. Plasma lipids and lipoproteins have been studied in control subjects and patients with various types of steatorrhoea.

2. Low plasma cholesterol levels were found in malabsorbers and were associated with decreased amounts of low-density lipoprotein (LDL) in males and high-density lipoprotein (HDL) in females.

3. Serum triglyceride levels were normal in males, but exceeded control values in some of the females, due to an increase in very-low-density lipoprotein.

4. LDL composition was abnormal in both male and female malabsorbers, with a decreased proportion of cholesterol ester and an increased proportion of triglyceride. There was also an increased proportion of triglyceride in HDL.

5. These findings show that malabsorption markedly influences not only the concentration but also the composition of plasma lipoproteins.
The Absorption of the Diastereoisomers of 5-Methyltetrahydropteroylglutamate in Man: A Carrier-Mediated Process
Authors: Weir D. G. , Brown J. P. , Freedman D. S. , Scott J. M.
Published: August 2015

1. The two diastereoisomers of 5-methyltetrahydropteroylglutamate, the form of folate that predominates in food and bile, were prepared chemically.

2. Their intestinal absorption was compared by means of the urinary-excretion method of 3H-labelled compounds and it was found that the naturally occurring biologically active isomer was excreted to a greater extent. Studies of the clearance of the two forms after intravenous injection showed that this difference was due to preferential intestinal absorption of the naturally occurring isomer.

3. In four patients with coeliac disease, the absorption of the naturally occurring isomer was depressed to the same range as the inactive isomer.

4. Since the two diastereoisomers are chemically inseparable, these results indicate that a carrier-mediated process is involved in the human intestinal absorption of this form of reduced folate.
Renal Handling of Calcium, Magnesium, Inorganic Phosphate and Hydrogen Ions during Prolonged Exposure to Elevated Carbon Dioxide Concentrations
Authors: Gray S. P. , Morris J. E. W. , Brooks C. J.
Published: August 2015

1. Fifteen healthy young men were exposed to an atmosphere of 0–7% CO2 in air for 7 weeks.

2. For 1 week before and during the exposure to CO2, serum calcium, magnesium and inorganic phosphate (Pi) levels were measured at intervals, together with 24 h urinary excretion of these three components, and net urinary acid excretion.

3. The urinary excretion of Ca2+, Mg2+ and Pi fell during exposure to CO2, whereas the serum levels of these components increased.

4. Serum levels of calcium were inversely correlated with urinary Ca2+ excretion both in control conditions and during exposure to CO2

5. An increase in urinary acid excretion in the third to fourth week of exposure to CO2 was associated with an increase in the urinary excretion of Ca2+, but not of Mg2+.

6. It is suggested that there is a difference from the normal in the renal handling of H+ and Ca2+ ions during exposure to CO2 which may lead to a retention of Ca2+ in the tissues.
The Hydrolysis of Glycine Oligopeptides by Guinea-Pig Intestinal Mucosa and by Isolated Brush Borders
Authors: Peters T. J.
Published: August 2015

1. The relative rates of hydrolysis of a series of glycine homopeptides by guinea-pig small intestinal mucosa and by isolated brush borders have been studied. Oligopeptides up to and including hexaglycine were hydrolysed. No activity was detected against a series of homopolypeptides of molecular weight 10000–100000.

2. Except for activity against diglycine, the peptidase activity was greater in the brush-border fraction than in the original homogenate. The relative activity of the peptidase in the brush borders compared to the homogenate increased with increasing length oligopeptide substrate.

3. Analysis of the enzyme reaction products indicated that the brush border contained an exopeptidase. Studies with peptide derivatives containing N- and C-terminal blocking groups and with tetraglycine synthesized with either the N- or C-terminal residues labelled, demonstrated that the brush borders contained an amino-oligopeptidase.

4. Studies with inhibitors and with purified gastric and pancreatic enzymes indicated that this glycine oligopeptidase activity was not due to enzymes from the intestinal lumen which had been adsorbed to the brush borders.
The Effects of Therapeutic Decrease in Packed Cell Volume on the Responses to Exercise of Patients with Polycythaemia Secondary to Lung Disease
Authors: Harrison B. D. W. , Davis Jane , Madgwick R. G. , Evans Marion , Prime F. J.
Published: August 2015

1. Progressive exercise and circulatory studies are reported on a selected group of patients with hypoxaemia and secondary polycythaemia before and after therapeutic decrease of packed cell volume.

2. A significant increase in exercise tolerance was demonstrated in a group of seven patients who claimed subjective benefit from the treatment.

3. No important circulatory changes were detected at rest after treatment.

4. During steady exercise mean pulmonary artery pressure at any given cardiac out-put was lower after treatment suggesting a fall in pulmonary vascular resistance.

5. During steady exercise oxygen consumption was increased in five of six patients subjectively improved by the treatment but no consistent changes in arterial lactate concentration or lactate/pyruvate ratio were observed.
Effect of High-Salt, High-Carbohydrate, Low-Protein Diet on Hypertension in the Rat
Authors: Ueda Hideo
Published: August 2015

1. High-salt, high-carbohydrate and low-protein diet induces remarkable elevation of blood pressure in spontaneous hypertensive rats (SHR).

2. These animals have low serum potassium, low blood urea nitrogen and high blood sugar.

3. Heart weight is increased in proportion to the elevation of blood pressure.

4. Kidney weight of rats receiving the high-salt, high-carbohydrate and low-protein diet was, by contrast, smaller than SHR receiving a normal diet.

5. The kidneys of SHR receiving a high-salt, high-protein diet were twice as heavy as the kidneys of normal rats.

6. Similar dietary modifications in Goldblatt hypertensive rats to those in SHR produced similar changes in blood pressure and heart weight.
Long-Term Study of Relationships between Blood Pressure, Age and Body Weight in Steelmill Workers
Authors: Ulrych M. , Tauber J. , Shapiro A. P.
Published: August 2015

1. In 404 male steelmill workers blood pressure and body weight were followed for 15–25 years and their relationships analysed.

2. It appears that age on average has a negligible influence on diastolic pressure and has a positive influence on systolic pressure only after 45 years of age.

3. In contrast to this, weight gain influences both pressures positively regardless of age.