bluuebunny/crossref_metadata_2025_split huggingface dataset:
Haemodynamic Changes in Long-Term Therapy of Essential Hypertension: A Comparative Study of Diuretics, α-Methyldopa and Clonidine
Authors: Lund-Johansen P. 
Published: August 2015

1. The effects of hypotensive therapy with three separate diuretics, methyldopa and clonidine were separately assessed.
2. All the treated groups showed a significant drop in blood pressure.
3. Polythiazide and hydrochlorothiazide each produced a significant fall in total peripheral resistance, whereas chlorthalidone did not.
4. Symptomless hypokalaemia was the only side effect seen with diuretics.
5. Methyldopa and clonidine reduced heart rate and cardiac index, but not total peripheral resistance.
6. The latter drugs also produced dry mouth, lassitude and drowsiness.
The Clearance of Endogenous Renin in the Anhepatic Anephric Dog
Authors: Fagard R. , Eyskens E. , Delooz H. , Fossion E. , Amery A. 
Published: August 2015

1. A rapid fall in plasma renin concentration occurs not only in colonectomized but also in hepatectomized dogs after binephrectomy.
2. In the anhepatic anephric dog no renin extraction can be demonstrated across lungs, splanchnic region, spleen, inferior limb and head.
3. No renin inactivation occurs in blood kept in vitro at 37°C for 3 h taken from anaesthetized dogs and from the anhepatic anephric dogs.
4. We suggest that the clearance of renin in the anhepatic anephric dog is due to extraction or inactivation of renin by tissues in general.
Metabolic Clearance Rate of Angiotensin II in Arterial Hypertension
Authors: Coli A. , Donato L. 
Published: August 2015

1. Plasma metabolic clearance rate of mono-[125I]iodoangiotensin II was measured in seventeen patients with various disorders of the renin-angiotensin-aldosterone system. The measurements were carried out by using a new method which accounts for the contribution of labelled split products.
2. A significant correlation was obtained (P < 0.01), when plasma metabolic clearance rate was related to mean blood pressure level and the correlation appeared independent of angiotensin II presumed concentration.
3. A possible additional control mechanism of angiotensin II degradation is suggested.
RIASSUNTO
1. Gli autori hanno misurato la clearance metabolica della mono-[125I]iodoangiotensina II in 17 pazienti con varie alterazioni del sistema renina-angiotensina-aldosterone. Il metodo impiegato permette la sottrazione diretta della radioattività plasmatica dovuta all'angiotensina, da quella dei frammenti marcati.
2. Si osserva una correlazione significativa (P < 0.01), quando i valori di clearance sono confrontati con quelli della pressione arteriosa media.
3. Viene supposto un ulteriore possibile sistema di controllo nella degradazione della angiotensina II.
Synthesis of Renin Inhibitors
Authors: Poulsen K. , Burton J. A. , Haber E. 
Published: August 2015

1. To examine the substrate specificity of renin a series of analogues of a noctapeptide previously shown to be an effective substrate (Skeggs, Lentz, Kahn & Hochstrasser, 1968) were synthesized.
2. These peptides were studied both with respect to their actions as competitive inhibitors and as substrates.
3. This resulted in the identification of two peptides which were potent competitive inhibitors but could not be cleaved by renin.
Renin Suppression in Hypertension in Relation to Body Fluid Volumes, Patterns of Sodium Excretion and Renal Haemodynamics
Authors: Schalekamp M. A. D. H. , Krauss X. H. , Kolsters G. , Schalekamp M. P. A. , Birkenhäger W. H. 
Published: August 2015

1. In patients with essential hypertension plasma renin concentration (PRC) was assessed in relation to age, plasma volume, extracellular fluid volume, aldosterone secretion rate, renal vascular resistance, filtration fraction and excess sodium excretion after acute salt loading.
2. Up to a calculated renal vascular resistance of 20 000 dyn s cm−5, PRC was found to be inversely related with the above-mentioned variables except plasma volume, extracellular fluid volume and aldosterone secretion rate.
3. It is concluded that the phenomenon of renin suppression is not dependent on mineralocorticoid excess. Instead, a decrease in PRC together with hypernatriuresis appears to reflect a progressive switch in intrarenal haemodynamic relationships. Renin suppression should therefore be considered to be a feature of progressive, but still uncomplicated, essential hypertension.
Prognosis in Arteriosclerotic Renovascular Hypertension
Authors: Pinedo H. M. , De Graeff J. , Struyvenberg A. 
Published: August 2015

1. A comparison has been made of surgical and medical treatment in patients with arteriosclerotic renal artery stenosis and hypertension.
2. Immediate post-operative blood pressure was often normal, but frequently rose again later. After the sixth year only about 25% of surgical patients were normotensive without drug treatment.
3. Nephrectomy and vascular reconstruction gave similar results.
4. We presently believe that post-operative anticoagulant therapy is indicated in patients undergoing surgery for arteriosclerotic renal artery stenosis.
Effect of Phenobarbitone on Plasma [14C]Bilirubin Clearance in Patients with Unconjugated Hyperbilirubinaemia
Authors: Black M. , Fevery J. , Parker D. , Jacobson J. , Billing Barbara H. , Carson E. R. 
Published: August 2015

1. The clearance of a tracer dose of [14C]bilirubin from the plasma was studied in patients with Gilbert's syndrome, congenital non-haemolytic jaundice, haemolytic jaundice and in normal subjects. Clearance was significantly impaired in the patients with Gilbert's syndrome and in those with congenital non-haemolytic jaundice when compared with the normal subjects, and was normal in the patient with haemolytic jaundice.
2. Treatment for 2 weeks with phenobarbitone (180 mg/day) lowered the plasma bilirubin concentration and improved all indices of plasma clearance of the isotope in patients with Gilbert's syndrome, so that they became indistinguishable from those of normal subjects. The improvement in plasma [14C]bilirubin clearance in these patients was associated with modest increases in hepatic bilirubin glucuronyl transferase in some subjects.
3. Phenobarbitone treatment improved plasma bilirubin concentrations and plasma [14C]bilirubin clearance in patients with congenital non-haemolytic jaundice, so that they resembled those seen in patients with untreated Gilbert's syndrome. Despite this improvement hepatic bilirubin glucuronyl transferase activity remained undetectable.
4. These results are compatible with the hypothesis that Gilbert's syndrome is a manifestation of a relative deficiency of hepatic bilirubin glucuronyl transferase, and differs from congenital non-haemolytic jaundice only in severity.
The Effect of Modifying the Combination of Insulin with Rat Adipose Cells on the Intracellular Levels of Cyclic Amp
Authors: Jerums G. , Galton D. J. , Gilbert C. 
Published: August 2015

1. Isoprenaline (1 μmol/l) and glucagon (1 μmol/l) raised the levels of cyclic AMP in isolated adipose cells of the rat to a maximum after incubation for approximately 15 min.
2. The effect of glucagon was impaired by pretreatment of adipose cells with trypsin (0.2 mg/ml and 2.0 mg/ml) and N-ethylmaleimide (5 mmol/l). The β-adrenergic receptor was insensitive to such forms of treatment.
3. Insulin (430 μunits/ml) lowered the intracellular levels of cyclic AMP in adipose cells stimulated with isoprenaline (1 μmol/l) and glucagon (1 μmol/l). This effect was observed after incubation for 5 min.
4. Pretreatment of cells with trypsin (0.2 mg/ml and 2.0 mg/ml) and N-ethylmaleimide (0.5 and 5 mmol/l) abolished the effect of insulin in decreasing the intracellular levels of cyclic AMP. At the higher concentration of trypsin a rise in intracellular levels of cyclic AMP was observed in the presence of insulin.
5. Similar concentrations of trypsin and N-ethylmaleimide decreased the disappearance of unlabelled insulin from the incubation medium and also decreased the binding of 125I-labelled insulin to isolated fat cells.
6. The effect of insulin on decreasing the intracellular levels of cyclic AMP in modified adipose cells significantly correlated with the disappearance of unlabelled insulin from the medium and with the percentage of total 125I-labelled insulin bound to cells.
7. The possibility is discussed of using the disappearance of insulin or binding of 125I-labelled insulin to adipose cells as a measure of insulin-receptor availability on the plasma membrane of fat-cells.
The Relationship between Arterial Pco2 and Hydrogen Ion Concentration in Chronic Metabolic Acidosis and Alkalosis
Authors: Bone J. M. , Cowie J. , Lambie Anne T. , Robson J. S. 
Published: August 2015

1. An analysis was made of the relationship which exists between arterial [H+], Pco2 and [HCO3−] in twenty-five patients with stable metabolic acidosis and alkalosis and in three normal subjects.
2. Contrary to previous reports, the relationship between Pco2 and [H+] was nonlinear and could best be described in terms of a rectangular hyperbola (Pco2 = 962/([H+]-12).
3. The relationship between Pco2 and [HCO3−] was curvilinear and best described by the quadratic function 23.8 (Pco2)2−12Pco2[HCO3−] −962 [HCO3−] = 0.
4. The small acute changes in [H+],−[HCO3−] and Pco2 produced by infusion of the weak organic acid 5,5−dimethyl 2,4−oxazolidinedione (DMO) could be predicted from the curvilinear regression.
The Effect of Diphenylhydantoin on Insulin Response
Authors: Cudworth A. G. , Cunningham J. L. 
Published: August 2015

1. Serum immunoreactive insulin, glucose tolerance and growth hormone levels were estimated in healthy volunteers before and after receiving diphenylhydantoin sodium (DPH) for 14 days.
2. With a standard oral dose of DPH all subjects showed a reduced insulin response to oral glucose (11–44%). This correlated with the serum concentration of the drug, which ranged from 30.5 to 90.0 μmol/l (7.7–22.7 μg/ml).
3. Glucose tolerance remained normal and no changes in growth hormone levels were observed.
4. Different doses of DPH have been employed in the treatment of insulinoma and as a screening test for detecting latent insulin secretory defects. This study confirms the wide inter-individual variation in the metabolism of DPH, and stresses both the importance of measuring the serum concentration of DPH and the comparative irrelevance of dosage levels in these situations.
Haemodynamic Effects of Intravenous Frusemide in Patients with Myocardial Infarction and Left Ventricular Failure
Authors: Tattersfield Anne E. , McNicol M. W. , Sillett R. W. 
Published: August 2015

1. Intravenous frusemide has been given to thirty-five patients with myocardial infarction and clinical signs of left ventricular failure. The haemodynamic changes following frusemide were then observed over the subsequent 6 h.
2. Frusemide produced a large diuresis, which was maximal during the first 2 h but fluid depletion was maintained at 24 h. The greatest diuresis occurred in patients with the highest stroke index.
3. All patients showed a fall in pulmonary artery pressure after frusemide. In patients with evidence of poor left ventricular function (low stroke index, high pulmonary artery pressure) this was associated with little change in stroke index. In patients with less severe impairment of left ventricular function there was an initial fall in stroke index at 1 and 2 h.
4. Six hours after frusemide there was a reduction in both pulmonary artery pressure and systemic arterial pressure; the latter correlated with the volume of the diuresis.
The Mechanisms by which Sodium Excretion is Increased during a Fast but Reduced on Subsequent Carbohydrate Feeding
Authors: North K. A. K. , Lascelles D. , Coates Pandora 
Published: August 2015

1. The excretion of electrolytes was studied in six obese subjects before, during and after a 7 day fast.
2. Despite a constant sodium intake throughout the study, there was a marked but transient increase in sodium excretion during the fast, and a sharp reduction in sodium excretion on resuming the carbohydrate diet.
3. Fasting was associated with an increase in the excretion not only of sodium but also of potassium, magnesium, calcium, ammonium, titratable acid, chloride, phosphate, sulphate and organic acids. Refeeding was associated with a prompt reduction in the excretion of all ions other than chloride.
4. The patterns of electrolyte excretion indicated that a major factor responsible for the increased excretion of sodium on fasting and for the retention of sodium on refeeding was a failure of ammonium excretion to keep pace with the changing output of organic acid.
Effect of Triterpenoids Related to Carbenoxolone upon Human Pepsins and Pepsinogens and upon Bovine Trypsin and Chymotrypsin
Authors: Waft Lesley A. , Roberts N. B. , Taylor W. H. 
Published: August 2015

1. Sixteen triterpenoid compounds, related to glycyrrhetic acid, have each been tested for anti-pepsin, anti-pepsinogen, anti-trypsin and anti-chymotrypsin activity. Their actions are compared with the known inhibitory actions of the triterpenoid, carbenoxolone, which is clinically effective in the healing of chronic gastric ulceration in man.
2. One of these compounds, 3-O-lauroyl-11-oxo-18α-olean-12-en-30-oic acid is known to be clinically ineffective in the healing of human gastric ulceration, and is found to have no inhibitory action upon any of the enzymes tested.
3. Anti-pepsin activity is affected by the nature of the side chain in the C-3 position, by substitution in the C-30 position, and by cleaving the A-ring. Anti-pepsinogen activity is affected by substitution into the C-28 position and/or by loss of the 11-oxo group.
4. The results enable suggestions to be made for the synthesis of new anti-pepsin and potential anti-ulcer triterpenoid derivatives.
5. The homologous enzymes, human pepsin 3 and swine pepsin A, are each affected similarly by the sixteen compounds. The correlation between effects of the compounds on pairs of enzymes may thus be used as a measure of the structural similarity of the enzymes. The correlation coefficients are high among the individual pepsins and among the individual pepsinogens.
6. It is also suggested that those triterpenoids which have anti-trypsin and anti-chymotrypsin activity may have a potential value in diseases in which pancreatic enzymes are released.
Hepatic Protein Binding of Folate
Authors: Corrocher R. , De Sandre G. , Pacor M. L. , Hoffbrand A. V. 
Published: August 2015

1. Binding of tritiated folic acid to rat liver cell cytoplasmic proteins has been studied in vitro and in vivo by Sephadex G75 column chromatography.
2. Studies in vitro show that folic acid is bound mainly in the ‘Y’ and ‘Z’ protein fractions, which have previously been described as binding other organic anions, e.g. bilirubin, sulphobromophthalein.
3. At 10 min after injection of tritiated folic acid in vivo, radioactive folates in liver cytoplasm were largely bound to X and Z protein fractions, with a smaller fraction bound to the Y fraction. At 24 and 48 h, radioactive folates were bound largely to the X and Y protein fractions.
4. It is suggested that the Y and Z proteins or closely related proteins may be involved in transfer of folates from plasma to liver, the major store of folate in the body.
Plasma Amino Acids in Experimental Acute Hepatic Failure and Their Relationship to Brain Tryptophan
Authors: Buxton B. H. , Stewart D. A. , Murray-Lyon I. M. , Curzon G. , Williams R. 
Published: August 2015

1. Sixteen plasma amino acids were measured serially in an experimental model of acute hepatic failure produced in the pig by devascularization of the liver.
2. Significant increases in the concentration of glycine, alanine and methionine were observed.
3. Altered concentrations in plasma of neutral amino acids which compete with tryptophan for transport into the brain had no apparent influence on brain tryptophan concentration.
Cell Sodium, Potassium and Water in Uraemia and the Effects of Regular Dialysis as Studied in the Leucocyte
Authors: Patrick J. , Jones N. F. 
Published: August 2015

1. The leucocyte has been used as a model for the study of intracellular sodium, potassium and water in uraemia. The advantages of this cell are described.
2. In undialysed patients with advanced renal failure leucocyte sodium and water contents were significantly greater than normal. Leucocyte potassium content (mmol/kg of dry solids) and concentration (mmol/l of cell water) were reduced.
3. In patients receiving regular dialysis leucocyte water was significantly reduced. Leucocyte potassium content was also reduced in this group, but leucocyte potassium concentration in cell water had returned to normal.
4. In the normal subjects and also in the dialysed patients leucocyte water correlated better with potassium than with sodium content. In contrast, in the undialysed uraemic patients leucocyte water correlated better with sodium than with potassium content, indicating that the increased cell sodium was an important determinant of the increased cell water in this group.
Plasma Tocopherol Levels and the Susceptibility of Erythrocytes to Heinz Body Formation
Authors: Tudhope G. R. , Hopkins J. 
Published: August 2015

1. The formation of Heinz bodies, after exposure of erythrocytes to hydrogen peroxide vapour, was significantly greater in cells from patients with plasma tocopherol levels of 11·6 μmol/l (5 mg/1) or less than in those from subjects with plasma tocopherol levels greater than 11·6 μmol/l.
2. Six patients with low plasma tocopherol levels received intramuscular or oral tocopherol for 3–14 days. In four cases, the abnormally great production of Heinz bodies by hydrogen peroxide was much reduced after tocopherol therapy.
3. The addition of tocopherol to suspensions of erythrocytes from such patients markedly reduced the Heinz body formation by hydrogen peroxide in two out of six cases.
4. In one case of erythrocyte glutathione peroxidase deficiency, where the plasma tocopherol concentration was normal, exposure of the erythrocytes to hydrogen peroxide resulted in abnormally great Heinz body formation. On repeating the experiment after the patient had received daily tocopherol injections for 5 days, the production of Heinz bodies by hydrogen peroxide was then no greater than in erythrocytes from normal subjects.
5. The effect of phenylhydrazine in producing Heinz bodies in erythrocytes in vitro was significantly reduced by the addition of tocopherol to the erythrocyte suspension; tocopherol had no significant effect on Heinz body formation by other oxidant drugs tested.
The Effect of Angiotensin upon the Vasculature of the Isolated Perfused Rat Kidney
Authors: Cross R. B. , Trace J. W. , Vattuone J. R. 
Published: August 2015

1. The effect of angiotensin II-amide upon the intrarenal distribution of perfusate was studied in the isolated rat kidney.
2. Low concentrations of angiotensin, 4·86 pmol/l (0·005 μg/l), reduced the flow rate through the papilla but did not alter total flow.
3. Higher concentrations of angiotensin, 0·486 nmol/l (0·5 μg/l), reduced total renal flow but did not decrease papillary perfusion.
4. In these experiments the perfusion pressure was maintained constant, indicating that the changes in flow were due to a direct effect of angiotensin upon the renal vasculature.
Post-Heparin Lipolytic Activity and Tissue Lipoprotein Lipase Activity in the Alloxan-Diabetic Rat
Authors: Elkeles R. S. , Williams E. 
Published: August 2015

1. Alloxan-diabetic rats showed raised plasma triglyceride levels and low adipose tissue lipoprotein lipase activity compared with controls. Heart lipoprotein lipase activity appeared unaltered by the diabetic state.
2. Plasma post-heparin lipolytic activity was slightly but not significantly increased in the diabetic group. The significance of these findings is discussed.
Competition between Carnosine and other Peptides for Transport by Hamster Jejunum in Vitro
Authors: Addison Jill M. , Matthews D. M. , Burston D. 
Published: August 2015

1. This paper reports the results of experiments on competition for transport by hamster jejunum in vitro between carnosine (β-alanyl-l-histidine) and other peptides and amino acids. Carnosine was chosen because this dipeptide is taken up intact with very little hydrolysis, which simplifies interpretation of the results.
2. Jejunal uptake of carnosine was inhibited by equimolar glycylglycine, glycylglycylglycine, glycylsarcosine, glycylproline, methionylmethionine and prolylhydroxy-proline but not by the equivalent free amino acids, or by a mixture of β-alanine and histidine. Inhibition of carnosine uptake by glycylproline was shown to be competitive. It is suggested that carnosine and the dipeptides inhibiting its uptake enter the mucosal cells by a common mechanism which is independent of the entry mechanisms for amino acids. Uptake of carnosine was not inhibited by N-acetylglycylglycine or by glycylglycine amide, suggesting that these substitutions prevent glycylglycine utilizing the dipeptide-uptake mechanism.
3. Carnosine uptake was not inhibited by equimolar lysyllysine or α-glutamylglutamic acid, nor did lysyllysine and α-glutamylglutamic acid affect uptake of each other. Though these results are compatible with the existence of multiple dipeptide-uptake systems in the intestinal mucosa, the evidence at present available is insufficient to permit any conclusion on this point.
Mental Retardation, Megaloblastic Anaemia, Methylmalonic Aciduria and Abnormal Homocysteine Metabolism Due to an Error in Vitamin B12 Metabolism
Authors: Dillon M. J. , England J. M. , Gompertz D. , Goodey Patricia A. , Grant D. B. , Hussein H. A-A. , Linnell J. C. , Matthews D. M. , Mudd S. H. , Newns G. H. , Seakins J. W. T. , Uhlendorf B. W. , Wise Irene J. 
Published: August 2015

1. The case is described of a child with retarded physical and mental development, recurrent megaloblastic anaemia, methylmalonic aciduria and abnormal homocysteine metabolism resulting from an inborn error in the metabolism of cobalamins. She died at the age of 7 years. At autopsy there was pulmonary fibrosis and the brain showed lesions typical of those seen in subacute combined degeneration of the cord.
2. A metabolic abnormality was present which resulted in an inability to maintain normal tissue concentrations of the two coenzyme forms of vitamin B12, methylcobalamin and adenosylcobalamin. Lack of methylcobalamin led to deficient activity of N5-methyltetrahydrofolate-homocysteine methyltransferase with reduced ability to methylate homocysteine, and lack of adenosylcobalamin to deficient activity of methylmalonyl-CoA mutase, which accounted for the methylmalonic aciduria.
3. Analyses of total vitamin B12 and of individual cobalamins by a chromatobioautographic technique showed that in organs sampled at autopsy, the content of total vitamin B12 and of methylcobalamin, adenosylcobalamin and hydroxocobalamin were all greatly reduced. The plasma had a high normal total vitamin B12 content, but showed a gross abnormality in the distribution of individual cobalamins, methylcobalamin being decreased and adenosylcobalamin and hydroxocobalamin increased. The erythrocytes showed a reduction in cobalamins resembling that in the solid organs, though less severe.
4. The underlying abnormality in this patient appeared to be either a defect in cellular uptake of vitamin B12, or a defect in a metabolic pathway leading to the formation of a common precursor of methylcobalamin and adenosylcobalamin. Abnormalities in transcobalamins I and II, plasma factors involved in plasma transport and cellular uptake of vitamin B12, were excluded.
5. The clinical and biochemical findings in the patient are compared with those described in three patients previously reported, who had methylmalonic aciduria and homocystinuria, and who were in some respects similar to this patient. The present case is unusual in that previous examples of errors in cobalamin metabolism have not had megaloblastosis or neurological changes typical of vitamin B12 deficiency. It is also the first case in which direct estimations of individual cobalamins have been made.