bluuebunny/crossref_metadata_2025_split huggingface dataset:
Superoxide anion production and degranulation of rat neutrophils in response to acetaldehyde-altered liver cell membranes
Authors: Williams A. J. K. , Barry R. E. 
Published: August 2015

1. Rat liver membrane vesicles were exposed to acetaldehyde, with or without reduction of the resultant adducts formed.
2. Superoxide anion production and degranulation of rat neutrophils, upon stimulation with the liver membrane vesicles, were measured by cytochrome c reduction before and after the addition of superoxide dismutase, and β-glucuronidase release respectively.
3. Preincubation with acetaldehyde significantly enhanced superoxide anion production by both the reduced and non-reduced membrane samples (1.7-fold and 4.4-fold, respectively).
4. Preincubation with acetaldehyde significantly enhanced degranulation (1.5-fold) of neutrophils in response to the non-reduced membranes only. The reductive process itself caused a marked increase (2.4-fold) in the ability of the membrane vesicles to stimulate degranulation.
5. Cytochalasin B, an inhibitor of phagocytosis, did not reduce degranulation, implying that it occurred as a consequence of cell surface stimulation.
6. Neutrophil superoxide anion production and lysosomal enzyme release in response to acetaldehyde-altered liver cell membranes could be an important mechanism of hepatocyte injury in alcoholic liver disease.
Insulin resistance and regulation of serum amino acid levels in myotonic dystrophy
Authors: Moxley Richard T. , Kingston William J. , Minaker Kenneth L. , Corbett Alastair J. , Rowe John W. 
Published: August 2015

1. To quantify the degree of whole body insulin resistance in patients with myotonic dystrophy and to determine if these same patients display signs of a whole body decrease in the action of insulin on amino acid uptake and glucose disposal, three separate 120 min studies employing the euglycaemic insulin clamp technique (20, 80 and 200 m-units min−1 m−2) were performed on five ambulatory patients with myotonic dystrophy. The results were compared with findings obtained in identical studies in 21 normal volunteers.
2. Myotonic dystrophy patients showed a slower, less marked decline in the serum concentration of insulin sensitive amino acids (threonine, valine, leucine, isoleucine, tyrosine, phenylalanine) during all three insulin infusions compared with normals. The greatest difference occurred at the low physiological elevations of insulin produced by the 20 m-units min−1 m−2 infusion.
3. Alanine levels fell significantly below baseline in patients with myotonic dystrophy after 60 and 120 min of insulin infusion with all three rates of insulin infusion. Normal subjects had only a minimal, insignificant decline in arterialized alanine concentrations during the three different insulin infusions.
4. Creatinine adjusted rates of whole body glucose disposal were 30–40% lower in the myotonic dystrophy group at all three doses of insulin compared with the normals. This demonstrates that their insulin resistance was not due simply to a reduction in muscle mass.
5. The overall pattern of findings in these studies of patients with myotonic dystrophy indicates that there is a whole body derangement in the regulation of circulating amino acid levels by insulin as well as a marked decrease in the action of this hormone in stimulating glucose uptake by target tissues.
Stereophotogrammetry for measuring rates of cutaneous healing: A comparison with conventional techniques
Authors: Bulstrode C. J. K. , Goode A. W. , Scott P. J. 
Published: August 2015

1. A portable stereocamera linked to a computer has been developed capable of taking photographs in the clinical situation.
2. The accuracy and precision of this system has been measured and compared with direct tracing and simple photography, the two systems currently in use for this type of work. It was found to have a precision of better than 2% and to be accurate to within 1% for edge length and area in models of chronic leg ulcers whose dimensions were known exactly. These results are between five and ten times better than direct tracing and simple photography measured under similar circumstances.
3. When used on patients' ulcers, stereophotogrammetry was found to have a precision of 2% for edge length and 3.4% for area, again between five and ten times more accurate than the other two systems.
4. The accuracy with which an epithelial edge can be identified with the naked eye, a possible limiting factor in any visual measuring system, was measured on fixed preparations of healing wounds on pigs. The mean error was found to be 240 μm with a confidence limit of 440 μm.
5. Finally, the rate of healing of chronic leg ulcers was measured in a clinical trial on patients. Only stereophotogrammetry had errors consistently smaller than the changes being measured in the clinical trial, making it the only system which can validly be used to study rates of healing in this model. It is also able to measure volume to within 5% and is unique in being able to do this non-invasively.
Enhancement of cardiac vagal action during ischaemia of the sino-atrial node
Authors: Potter Erica K. , McCloskey D. I. , Courtice Gillian P. 
Published: August 2015

1. The effect of ischaemia of the sino-atrial node on cardiac vagal action was studied in anaesthetized dogs.
2. The cut, cardiac end of the right vagus nerve was stimulated with a standard supramaximal stimulus every 10 s. The arterial supply to the sinoatrial node was occluded for periods of 1–3 min during this intermittent vagal stimulation.
3. Vagal action on heart rate was potentiated during ischaemia of the sino-atrial node.
Autonomic nervous control of the heart rate during dynamic exercise in normal man
Authors: Maceel B. C. , Gallo L. , Marin Neto J. A. , Lima Filho E. C. , Martins L. E. B. 
Published: August 2015

1. The relative contribution of the efferent components of the sympathetic and parasympathetic nervous systems to the heart rate (HR) response to dynamic physical exercise was evaluated in 23 normal males.
2. The dynamic exercise was performed on a bicycle ergometer at work loads of 25, 50 and 100 W, before and after pharmacological blockade with atropine (13 individuals) or propranolol (10 individuals).
3. Parasympathetic blockade significantly depressed the rapid HR response at the beginning of the exercise period at all levels of intensity, whereas sympathetic blockade only affected the slow-response phase (1–4 min), especially at the highest level of effort.
4. The present results suggest that the tachycardia evoked by dynamic exercise is mediated by a biphasic mechanism initially depending on rapid vagal release, which increases progressively with increasing effort. An increased sympathetic activity manifests itself in a more delayed manner, especially at the higher levels of activity.
5. Continuous monitoring of HR during the entire period of activity at different levels of intensity permits the utilization of dynamic exercise as a simple and non-invasive method for the functional evaluation of the two components of the autonomic nervous system of the heart.
Intracellular ion metabolism in erythrocytes and uraemia: The effect of different dialysis treatments
Authors: Trevisani Maurizio , De Santo Natale , Laurenzi Martin , Di Muro Michele , De Chiara Franco , Latte Maurizio , Franzese Antonietta , Iacone Roberto , Capodicasa Giuseppe , Giordano Carmelo 
Published: August 2015

1. The present report focuses on some aspects of the intra-erythrocytic cation metabolism (e.g. the maximal velocity of the Na+–Li+ countertransport and Na+/K+/Cl−1 cotransport) in uraemic patients on different dialysis treatments.
2. Patients undergoing dialysis treatment [continuous ambulatory peritoneal dialysis (CAPD) or haemodialysis (HD)] overall showed higher Na+–Li+ countertransport than controls. With regard to Na+/K+/Cl−1 cotransport, CAPD patients and controls did not differ and both showed, on average, higher values than HD patients.
3. A subgroup of HD patients was studied before and after dialysis. No significant overall changes were detected as a result of the dialysis process with regard to Na+/K+/Cl−1 cotransport. Na+-Li+ countertransport was significantly reduced by dialysis and a distinctly different response to dialysis was evident according to predialysis values. Patients with high values of Na+–Li+ countertransport showed a significant reduction in this parameter while patients with normal values showed no effect. No distinct association was detected between alteration in either Na+–Li+ countertransport or Na+/K+/Cl−1 cotransport and the clinical characteristics of the patients.
4. It is concluded that uraemia and/or dialysis influences the maximal velocity of the parameters under investigation. The effect on Na+–Li+ countertransport seems to be similar for both CAPD and HD, while Na+/K+/Cl−1 cotransport is not altered in CAPD patients.
Oestrogen-induced changes in renal haemodynamics in the rat: Influence of plasma and intrarenal renin
Authors: Evans Mr J. K. , Naish P. F. , Aber G. M. 
Published: August 2015

1. The effect of oestrone acetate (in total doses of 5 and 10 mg) on systemic and renal haemodynamics and the renin-angiotensin system has been studied in adult female rats.
2. The administration of 10 mg of oestrogen resulted in a significant fall in renal blood flow associated with significant rises in both renal vascular resistance and mean arterial pressure. No changes were noted in cardiac output or total peripheral resistance at either dose.
3. Whilst the higher dose of oestrogen induced a significant increase in plasma renin activity, no change was noted in animals receiving 5 mg of oestrogen. Both regimens caused significant reductions in plasma and intrarenal renin concentrations.
4. Although renal blood flow correlated with plasma renin activity in animals with a normal renal blood flow, no such correlation was noted in animals with oestrogen-induced reductions in renal blood flow.
5. The present study demonstrates that oestrogen-induced reductions in renal blood flow result from a rise in intrarenal vascular resistance which cannot be accounted for by simultaneous changes in either plasma renin activity or renal renin concentration.
Insulin action and dynamics modelled in patients taking the anabolic steroid methandienone (Dianabol)
Authors: Godsland I. F. , Shennan N. M. , Wynn V. 
Published: August 2015

1. Plasma glucose and insulin concentrations were measured during oral (OGTT) and intravenous (IVGTT) glucose tolerance tests in nine patients off- and on-treatment with the anabolic steroid, methandienone (Dianabol).
2. On-treatment, the tolerance tests showed a markedly increased insulin response accompanied by impairment of glucose tolerance, characteristics normally attributed to insulin resistance. However, fasting plasma glucose (FPG) and insulin (FPI) concentrations were significantly reduced, whereas the pattern normally associated with insulin resistance is for both to be raised.
3. IVGTT glucose and insulin profiles were analysed using an algorithm derived from the minimal models of glucose and insulin dynamics originally proposed by R. Bergman and co-workers. Measures for the following parameters were thus obtained: Si, the sensitivity of glucose disposal to insulin; Sg, net insulin independent glucose disposal; ϕ1, the integral concentration of insulin delivered during the first phase of insulin secretion relative to the initial increase in glucose concentration above a model-derived threshold; ϕ2 the sensitivity of the rate of rise of insulin concentration in the second phase of insulin secretion to the concentration of glucose above a model-derived threshold; κ, the fractional clearance rate of insulin; and tl/2, the insulin half-life.
4. Si was significantly reduced on treatment by a factor of 4. Sg, ϕ1, ϕ2 and t1/2 were all significantly increased, and κ was significantly reduced. The increases in Sg and ϕ1 both showed significant correlations with the increase in weight on-treatment.
5. The reduction in FPG and FPI can be explained by the combined effects of the increase in Sg and Dianabol-induced resistance to glucagon.
6. Application of the Bergman models proved to be of value in identifying and quantifying Dianabol-induced insulin resistance. Model-derived parameters of insulin clearance and net insulin independent glucose uptake were also of use in interpreting the changes in glucose and insulin concentrations observed. However, model-derived parameters of pancreatic insulin secretion were likely to have been confounded by reduced hepatic insulin uptake associated with a state of relative insulin resistance.
A study of intracellular orthophosphate concentration in human muscle and erythrocytes by 31P nuclear magnetic resonance spectroscopy and selective chemical assay
Authors: Bevington A. , Mundy K. I. , Yates A. J. P. , Kanis J. A. , Russell R. G. G. , Taylor D. J. , Rajagopalan B. , Radda G. K. 
Published: August 2015

1. In order to study the relationship between extracellular and intracellular concentrations of orthophosphate (Pi), phosphorus nuclear magnetic resonance spectra were recorded, at rest, from the flexor digitorum superficialis muscle of hypophosphataemic patients with vitamin D-resistant rickets, and patients with Paget's disease of bone before and after they had been made hyperphosphataemic by treatment with the drug ethylidene-1-hydroxy-1,1-bisphosphonate. Changes in intramuscular Pi were estimated from the ratio of the areas of the Pi to adenosine 5′-triphosphate peaks. Even though the plasma Pi concentration in these patients spanned a fourfold range (0.5–2.0 mmol/l) the corresponding intramuscular Pi concentration increased by only 70%.
2. A similar effect was observed in erythrocytes, from patients with these disorders, which were incubated in autologous plasma at 37°C, under an atmosphere of O2 + CO2 (95:5, v/v). However, chloride ions, which are transported passively across the cell membrane, showed no change in distribution between cells and plasma, indicating that there was no general effect on passive anion distribution.
3. When erythrocytes from normal subjects were incubated in autologous plasma (1.0 mmol of Pi/l) and in plasma supplemented with Pi (2.3 mmol of Pi/l), the Pi concentration in the cells, at steady state, increased only from 0.57 to 0.78 mmol/l cells, suggesting that the effect was not an artifact of disease or drug therapy.
4. It is concluded that, in human skeletal myocytes and erythrocytes, the percentage change in the concentration of cytoplasmic Pi is lower than that in plasma. This implies that these cells can buffer or regulate cytoplasmic Pi when the extracellular concentration is disturbed.
Autonomic mechanisms in the heart rate response to coughing
Authors: CaRdone Claudio , Bellavere Federico , Ferri Marcello , Fedele Domenico 
Published: August 2015

1. To differentiate between the possible reflex and mechanical components in the heart rate response to cough, eight healthy subjects performed a standardized cough test before and after pharmacological autonomic blockade; to test the clinical usefulness of the cough manoeuvre two groups of diabetic patients (without and with autonomic neuropathy) were compared with a group of age-matched normal subjects.
2. Because of the use of abdominal and expiratory muscles during cough, the cardioacceleratory response was compared with that induced by an intense contraction of the arm muscles (handgrip).
3. The cardioacceleratory response was completely abolished by atropine while propranolol failed to affect it. The diabetic patients with autonomic neuropathy showed a response similar to that after cholinergic blockade. The response was similar to that induced by muscular contraction for 4 s, after which it differed showing a continued cardioacceleration. The patterns of recovery were not different.
4. The cough-induced cardioacceleration is essentially reflex in nature and under cholinergic control; initially the mechanism may be partially related to the intense contraction of abdominal and expiratory muscles; later, the arterial hypotension related to the cough may contribute to the more sustained shortening of the R–R interval.
5. The cough test may be useful for the evaluation of cardiac parasympathetic integrity.
Renal ammoniagenesis following glutamine loading in intact dogs during acute metabolic acid–base perturbations
Authors: Areas Jorge , Balian Sevag , Slemmer Dianna , Belledonne Mario , Preuss Harry G. 
Published: August 2015

1. Adaptation of renal ammoniagenesis during acute metabolic acidosis in intact dogs may be nonexistent or, at least, markedly less than in chronic acidosis. This contrasts to adaptation in acute respiratory acidosis, where levels similar to those attained in chronic acidosis occur within hours.
2. Accordingly, the inability to discern marked changes in acute metabolic acidosis compared with acute respiratory acidosis has been attributed to decreased glomerular filtration rate and renal blood flow seen frequently in the former.
3. In our studies, we found early changes in ammoniagenesis and glutamine metabolism during acute metabolic acidosis, but not of the magnitude seen in chronic acidosis, even considering the changes in renal blood flow (RBF) and glomerular filtration rate (GFR). Exogenous glutamine loading allowed us to discover that the qualitative changes in glutamine metabolism during acute metabolic acidosis differed from control but fell short of those seen in chronic metabolic a acidosis.
4. We also examined glutamine metabolism when renal ammoniagenic adaptation was acutely inhibited in chronically acidotic dogs. Infusing NaHCO3 into chronically acidotic dogs decreased renal ammonia production significantly (247 μmol min−1 100 ml−1 GFR vs 148 μmol min−1 100 ml−1 GFR: P &lt; 0.001) and glutamine extraction (111.8 μmol min−1 100 ml−1 GFR vs 90.9 μmol min−1 100 ml−1 GFR: P &lt; 0.02).
5. The qualitative changes in renal glutamine metabolism in both studies suggest that alterations in deamination of glutamate formed from glutamine are responsible, at least in part, for adaptation to acute acid–base perturbations.
6. Compared with respiratory acidosis, adaptation to metabolic acidosis is progressive and prolonged.
The potential use of lithium as a marker for the assessment of the sources of dietary salt: Cooking studies and physiological experiments in men
Authors: Sanchez-Castillo C. P. , Seidell J. , James W. P. T. 
Published: August 2015

1. Lithium was investigated for its possible use as a marker for identifying the various sources of NaCl in the diet. Micromolar concentrations of lithium can be detected in various vegetables, tap water and also in urine specimens of adult volunteers. The lithium content of vegetables varied from 6.1 to 24.5 μmol of lithium/kg dry weight, with the exception of spinach and aubergines which had much higher concentrations. The excretion of the element in 24 h urine specimens ranged from 2 to 4 μmol of lithium/day.
2. Experiments were performed to assess whether both lithium and sodium would penetrate foods at the same rate during cooking. The rates of penetration into food for both elements were proportional to their concentration in the cooking water despite a sodium/lithium ratio of 50:1.
3. Physiological experiments were conducted to investigate the handling of small doses of lithium by the body. A dose of 250 μmol of lithium was chosen as optimal and given orally to healthy volunteers in either single or continuous aqueous doses of lithium carbonate. The recoveries of oral lithium in urine were 92 ± 5% (sd) and 97 ± 4 (sd) (n = 5) for single and continuous doses respectively.
4. The daily addition of 100 mmol of oral NaCl to the diet of volunteers receiving a standard dose of lithium did not affect urinary lithium excretion rates nor the final recovery of the administerd lithium.
5. These studies suggest that lithium carbonate may be a useful marker for the uptake of NaCl into cooked food; after eating lithium-enriched food the monitoring of urinary lithium output may then be used to quantify the amount of sodium derived from the specific foods.
Effects of changes in dietary sodium intake on aortic sodium pump activity in the rat
Authors: Bradlaugh Richard , Bing Robert F. , Swales John D. , Thurston Herbert 
Published: August 2015

1. Aortic smooth muscle sodium efflux was studied in normal rats undergoing salt restriction or salt loading.
2. Sodium efflux rate constant was not changed by salt loading but fell significantly with salt restriction. This change was not associated with a fall in blood pressure.
3. These studies show that smooth muscle sodium transport can be influenced by dietary salt intake but do not support the concept that salt loading leads to the inhibition of the vascular smooth muscle sodium pump.
Delayed postprandial plasma bile acid response in coeliac patients with slow mouth–caecum transit
Authors: Spiller R. C. , Frost P. F. , Stewart J. S. , Bloom S. R. , Silk D. B. A. 
Published: August 2015

1. Coeliac patients are known to have an expanded bile salt pool which recirculates slowly due, at least in part, to impaired gall bladder contractility. We have investigated the possibility that delayed small bowel transit of chyme and bile may also contribute to this sluggish recycling.
2. Plasma cholylglycine, total bile acids and cholecystokinin concentrations were measured after a lactulose-labelled test meal whose mouth-caecum transit time (M–C TT) was assessed by the breath hydrogen technique.
3. Overall there were no significant differences in plasma bile acid profiles between seven healthy controls and a group of 25 coeliac patients. However, when subjects were divided according to their M–C TT, the 10 with the slowest transit were found to have significant elevation of fasting levels when compared with the 10 with the fastest transit, fasting total bile acids being 3.4 ± 1.3 versus 0.7 ± 0.6 μmol/l (P &lt; 0.02) and fasting cholylglycine being 0.43 ± 0.17 versus 0.06 ± 0.04 μmol/l (P &lt; 0.05) respectively.
4. Peak bile acid levels did not differ significantly between subjects with fast or slow transit. However, subjects with slow transit were found to have a delay in the return of plasma bile acid levels to fasting levels so that the 4 h postprandial levels were significantly elevated when compared with those observed in the subjects with fast transit (total bile acids 3.6 ± 1.2 versus 0.19 ± 0.1 μmol/l and cholylglycine 0.70 ± 0.13 versus 0.24 ± 0.07 μmol/l respectively, both P &lt; 0.01).
5. We conclude that M–C TT is an important variable determining the postprandial plasma bile acid response, which should be considered when comparing different disease groups in whom gut motility may differ.
The effect of a synthetic polypeptide on the renal handling of protein in man
Authors: Beetham Robert , Dawnay Anne , Cattell William 
Published: August 2015

1. Haemaccel is a synthetic polymer of partially degraded gelatin and a widely used plasma volume expander.
2. The effect of a 17.5 g infusion of Haemaccel on protein excretion was investigated in four normal subjects.
3. The urinary excretion of two low molecular weight proteins, retinol-binding protein and β2-microglobulin, increased 1000- and 500-fold respectively above the values found after administration of saline as a control. The urinary excretion of albumin did not change significantly (P &gt; 0.5).
4. In the hour after Haemaccel administration the excretion of the two low molecular weight proteins approached at least 50% of a predicted filtered load.
5. This effect of Haemaccel may be due to inhibition of proximal tubular uptake or transport of the two proteins. Absence of any effect on albumin excretion suggests alternative mechanisms for its tubular reabsorption.
6. Haemaccel may be a valuable new agent for the study of renal tubular protein metabolism.