bluuebunny/crossref_metadata_2025_split huggingface dataset:
Circulating opioid peptides during water immersion in normal man
Authors: Coruzzi P. , Ravanetti C. , Musiari L. , Biggi A. , Vescovi P. P. , Novarini A. 
Published: August 2015

1. This study was designed to evaluate variations in plasma β-endorphin, methionine-enkephalin, adrenocorticotropic hormone and serum prolactin in healthy volunteers during head-out water immersion.
2. Water immersion induced an increase in methionine-enkephalin plasma levels, which was associated with a significant fall in mean arterial pressure and heart rate.
3. Conversely, a suppression of plasma β-endorphin, adrenocorticotropic hormone and serum prolactin was detected during water immersion.
4. We suggest that a dopaminergic inhibitory control mechanism may be involved in regulating circulating levels of β-endorphin, adrenocorticotropic hormone and prolactin in normal subjects undergoing extracellular fluid volume expansion produced by water immersion.
Trimethylaminuria (‘fish-odour syndrome’): A study of an affected family
Authors: Al-Waiz Makram , Ayesh Riad , Mitchell Stephen C. , Idle Jeffrey R. , Smith Robert L. 
Published: August 2015

1. Beginning with a single propositus, who had been previously diagnosed at the age of 10 as suffering from trimethylaminuria (fish-odour syndrome), both her parents and two sisters were investigated biochemically with respect to their ability to N-oxidize trimethylamine (TMA), both when derived from the diet and when administered exogenously.
2. Both the propositus and a second sister were markedly deficient in their ability to N-oxidize TMA, both when derived from the diet and when given as such; furthermore, both siblings readily developed the symptoms of fish-odour syndrome as characterized by a strong objectionable breath and body odour shortly after the oral administration of TMA (300 mg).
3. At this dose level of TMA, neither of the parents nor the third sister showed any evidence of impaired N-oxidation ability nor did they experience any ‘fish-odour’ symptoms.
4. With an oral challenge of 600 mg of TMA, both the parents showed a clear impairment of N-oxidation capacity which was not seen in six healthy unrelated volunteers. Both parents experienced a fish-odour syndrome at this level of TMA challenge.
5. The family data support the hypothesis that trimethylaminuria is an inborn error in the ability to N-oxidize TMA which is inherited as an autosomal recessive trait. Furthermore, experience with this family suggests that an oral challenge dose with 600 mg of TMA may be used to identify carriers of the condition.
Effects of heroin addiction on the responses of glucose, C-peptide and insulin to a standard meal
Authors: Zandomeneghi R. , Luciani A. , Massari M. , Montanari P. , Pavesi C. 
Published: August 2015

1. The aim of the study was to examine the responses of plasma glucose, C-peptide immunoreactivity (CPR) and total immunoreactive insulin (IRI) to a standard meal in heroin addicts, since the presence of immunoreactive β-endorphin has been demonstrated in human endocrine pancreas.
2. Ten heroin addicts and 10 control subjects participated in the study. The addicts had been taking heroin (from 0.5 to 2 g/day) for at least 2 months and they had no detectable diseases.
3. After a 12 h fast, each subject received a standard meal; blood samples were taken at − 15, 0, 15, 30, 60 and 120 min to determine glucose, CPR and IRI. Calculation of the CPR/IRI molar ratio was used as a semiquantitative estimation of the hepatic extraction of insulin.
4. No difference in plasma glucose was observed between the groups. Addicts had lower CPR than normals at 15, 30 and 120 min (P &lt; 0.01). On the contrary, IRI was higher in addicts than in normals (P &lt; 0.05 at − 15 and 0 min, P &lt; 0.01 at 15, 30 and 60 min), except at 120 min. The CPR/IRI molar ratio was lower in addicts (P &lt; 0.01).
5. Heroin addiction seems to produce a β-cell failure and contemporaneously a state of hyperinsulinaemia; blood glucose remains in the normal range.
6. We conclude that chronic heroin addiction may produce a change in the rate of hepatic extraction of insulin.
Effects of a specific antidiuretic agonist on cardiac output and its distribution in intact and anephric dogs
Authors: Liard Jean-Francois 
Published: August 2015

1. The specific antidiuretic agonist [4-valine, 8-d-arginine]vasopressin (VDAVP) was administered intravenously to seven conscious dogs at a rate of 10 ng min−1 kg−1. Cardiac output (aortic electromagnetic flowmeter), mean arterial pressure and regional blood flows (radioactive microspheres) were measured before and after 30 min of infusion.
2. Mean arterial pressure fell from 89.9 ± 4.5 (mean ± sem) to 82.3 ± 5.9 mmHg and cardiac output increased from 115.4 ± 8.7 to 163.0 ± 14.4 ml min−1 kg−1. Total peripheral resistance decreased from 41.6 ± 3.7 to 27.8 ± 3.6 units and heart rate increased from 79.2 ± 5.9 to 123.2 ± 5.9 beats/min. Blood flow increased significantly in the myocardium, fat and skeletal muscle vascular bed.
3. In another group of six dogs subjected to a similar protocol 24 h after bilateral nephrectomy, mean arterial pressure fell from 102.2 ± 5.3 to 82.7 ± 3.4 mmHg and cardiac output increased from 125.6 ± 3.0 to 171.2 ± 4.0 ml min−1 kg−1. Total peripheral resistance decreased from 39.3 ± 3.4 to 23.4 ± 1.3 units and heart rate increased from 84 ± 4.9 to 113.3 ± 4.3 beats/min. The increase in cardiac output and the fall in total peripheral resistance did not differ significantly between intact and anephric dogs. Regional blood flow responses differed in some respects in the two groups studied, but there was no evidence that the vasodilatory action of VDAVP depended on the presence of the kidneys.
4. These results indicate that the vasodilatation elicited by the antidiuretic agonist VDAVP in intact dogs is limited to a few vascular beds. Furthermore, this vasodilatation appears to be independent from the renal V2-vasopressin receptors.
Relative efficacy of oral verapamil and digoxin alone and in combination for the treatment of patients with chronic atrial fibrillation
Authors: Pomfret S. M. , Beasley C. R. W. , Challenor V. , Holgate S. T. 
Published: August 2015

1. The efficacy of verapamil alone, or in combination with digoxin, was compared with digoxin alone in eight patients with chronic atrial fibrillation in this double-blind placebo-controlled study.
2. After 2 weeks on each treatment regimen, heart rate at rest and during progressive load treadmill exercise, left ventricular function at rest and nocturnal heart rate were measured.
3. Oral verapamil alone at a dose of 80 mg three times daily, or 40 mg of verapamil three times daily in combination with 0.25 mg of digoxin daily, was superior to digoxin alone in doses associated with high serum digoxin concentrations (mean ± sem 1.6 ± 0.3 μg/l). This superiority manifested as greater control of heart rate during work rates equivalent to regular daily activities, and was not associated with deterioration in left ventricular function or worsening nocturnal bradycardia.
4. We conclude that the treatment of choice in patients with chronic atrial fibrillation is either 80 mg of verapamil three times daily or 40 mg of verapamil three times daily in combination with digoxin.
A randomized controlled trial of the effect on blood pressure of dietary non-meat protein versus meat protein in normotensive omnivores
Authors: Prescott Susan L. , Jenner David A. , Beilin Lawrence J. , Margetts Barrie M. , Vandongen Robert 
Published: August 2015

1. A randomized, controlled trial was carried out to examine whether changes in type and amount of dietary protein were responsible for earlier observations of blood-pressure-lowering effects of lacto-ovo-vegetarian diets.
2. Sixty-four subjects were pair-matched for sex, age, weight and sitting systolic blood pressure, and were randomly allocated to receive one of two types of protein supplement: one containing proteins from meat, the other proteins from non-meat sources. The supplements were balanced in terms of other nutrients. Consumption of other meat, poultry or fish was prohibited.
3. Sitting and standing blood pressures, weight, dietary intakes and plasma and urinary electrolytes were measured at regular intervals during the 12 weeks of trial. Urinary 3-methylhistidine was used as a measure of compliance.
4. Fifty subjects completed the trial. There were no statistically significant blood pressure differences between groups either at baseline or at end-of-trial, neither were there any substantive differences in mean blood pressure changes between baseline and end-of-trial. 3-Methylhistidine excretion was significantly lower in subjects on the non-meat diet.
5. The results suggest that the protein components of the lacto-ovo-vegetarian diet are not responsible for the blood-pressure-lowering effects of that diet.
Failure of impedance plethysmography to follow exercise-induced changes in limb blood flow
Authors: Hughson Richard L. 
Published: August 2015

1. The blood flow in the forearm and the calf of six healthy volunteers was measured at rest and after exercise by impedance plethysmography using pulsatile (QZp) and venous occlusion (QZocc) methods, and by venous occlusion strain gauge plethysmography (Qsg).
2. At rest, the impedance QZp method gave values slightly higher than those of Qsg. In the forearm, the ratio QZp to Qsg was 1.26 in the supine position and 1.97 in the upright sitting position. For the calf muscle, the ratios were 1.08 in the supine position and 1.23 in the upright position.
3. Immediately after exercise, Qsg increased from resting values of approximately 2–4 ml min−1 100 ml−1 to mean values of 16–25 ml min−1 100 ml−1 in upright and supine arm or leg exercise. In contrast, the QZp values after exercise increased to only 3.1–4.6 ml min−1 100 ml−1. QZocc likewise failed to show increases in flow except in the supine leg exercise, where flow increased to 8.7 ml min−1 100 ml−1.
4. In an additional subject, it was shown that electrode position had no significant effect on the QZp blood flow measurement after exercise.
5. The failure of QZp to accurately follow the change in Qsg with exercise was probably due in part to pulsatile venous outflow. In addition, changes in microvessel packed cell volume and shear rate may influence the observed QZp. It is concluded that impedance plethysmography is not valid for estimation of limb blood flow during reactive hyperaemia after exercise.
Rates of muscle protein synthesis in paraspinal muscles: Lateral disparity in children with idiopathic scoliosis
Authors: Gibson J. N. A. , McMaster M. J. , Scrimgeour C. M. , Stoward P. J. , Rennie M. J. 
Published: August 2015

1. The rate of paraspinal (multifidus) muscle protein synthesis was measured bilaterally at the top, apex and bottom of the thoracic curve in nine children with an idiopathic scoliosis, using the stable-isotope-labelled amino acid l-[1-13C]leucine.
2. No significant difference was observed in rates of muscle protein synthesis between the two sides of the spine, at the levels of the first vertebrae in neutral alignment at the top and bottom of the curve. However, in every patient, at the apex of the spinal curve, synthesis was higher on the convexity than on the concavity (0.077 ±0.04 %/h convex, 0.052 ±0.02 %/h concave, means ±sd, P &lt; 0.01).
3. Muscle RNA activity (μg of protein synthesized h−1 μg−1 of RNA) was lower at the curve apices on the concave than the convex side (0.019 ± 0.09 μg h−1 μg−1 convex apex, 0.016 ±0.06 μg h−1 μg−1 concave apex, P &lt; 0.05). Activities were similar on the two sides at the top and bottom of the curve.
4. Differences in muscle histology between the two sides were also observed only at the apex, with a lower type I fibre diameter (50.9 ±8.5 μm convex, 38.3 ±2.4 μm concave, P &lt; 0.05) and a lesser proportion of type I fibres (63 ± 12% convex, 49 ±9% concave, P &lt; 0.05) on the concavity.
5. The results are consistent with effects on muscle protein turnover secondary to an increased muscle contractile activity on the curve convexity and functional immobilization of the muscle on the curve concavity.
Fluoride therapy in osteoporosis: Acute effects on parathyroid and mineral homoeostasis
Authors: Stamp Trevor C. B. , Jenkins Michael V. , Loveridge Nigel , Saphier Peter W. , Katakity Monica , MacArthur Sarah E. 
Published: August 2015

1. Acute metabolic effects of sodium fluoride therapy were analysed among 41 osteoporotic patients already receiving large calcium supplements, 33 of whom underwent simultaneous metabolic balance studies.
2. Mean serum calcium fell transiently within 24–48 h by 0.03 ±0.07 (sd) mmol/l (P &lt; 0.01) and phosphorus by 0.06±0.08 (sd) mmol/l (P &lt; 0.001). In a subgroup, ionized calcium fell and biologically active parathyroid hormone (bio-PTH) rose more than fivefold (P &lt; 0.01). Urine calcium rose after an insignificant fall.
3. Pretreatment calcium and phosphorus balances were significantly positive and did not change overall during the first 8 days of treatment. However, on analysing balances in two groups relative to serum changes, in patients whose serum levels changed least sodium fluoride increased faecal calcium (P &lt; 0.025) and phosphorus (P &lt; 0.01) and reduced calcium balance (P &lt; 0.01), giving a mean balance difference between the two groups of 2.1 mmol daily (P &lt; 0.001).
4. Very small changes in serum levels therefore indicate well-marked metabolic responses: sodium fluoride acutely stimulates bio-PTH activity and must also enhance mineral uptake from circulation into tissue(s). By separate and opposing action(s) it inhibits intestinal calcium and phosphorus absorption, predominantly in those whose serum levels remain stable. All these effects may be relevant to long-term therapeutic results.
Atrial natriuretic peptide and adaptation of sodium urinary excretion in patients with chronic renal failure
Authors: Czekalski Stanislas , Michel Catherine , Dussaule Jean-Claude , Touraine Philippe , Mignon Francoise , Ardaillou Raymond 
Published: August 2015

1. In order to examine the potential role of endogenous atrial natriuretic peptide (ANP) in modulating the increased sodium excretion per nephron in chronic renal failure, we studied healthy subjects with normal renal function (group I) and patients with moderate (group II) or severe chronic renal failure (group III) before, during and after administration of an intravenous sodium load. All subjects had been on a controlled diet containing 120 mmol of sodium per day for 5 days before the study.
2. Under basal conditions, plasma ANP and fractional excretion of sodium (FENa) were highest in group III. Both parameters increased in response to the sodium load in the three groups studied (P &lt; 0.001). Changes with time differed from group to group (P &lt; 0.05), the more marked response for both parameters being observed in group III. After adjustment with respect to plasma ANP (analysis of covariance), FENa was no longer modified in response to the sodium load, whereas adjustment of FENa with respect to mean blood pressure was without consequence on the significance of its change with time. This demonstrates that plasma ANP, but not mean blood pressure, represents the main factor producing variation in FENa during and after the sodium load.
3. These results suggest an important role for plasma ANP in promoting adaptation of short-term sodium excretion in response to an acute sodium load in patients with chronic renal failure who ingest a normal sodium intake.
Effects of the somatostatin analogue SMS 201–995 (sandostatin) on mouth-to-caecum transit time and absorption of fat and carbohydrates in normal man
Authors: MøLler Niels , Petrany Guyla , Cassidy David , Sheldon William L. , Johnston Desmond G. , Laker Michael F. 
Published: August 2015

1. Somatostatin analogues, such as SMS 201–995 (sandostatin), have been suggested as treatment for a variety of disease states including acromegaly, secretory gastrointestinal tumours and diabetes mellitus.
2. Somatostatin-14 has actions to prolong gastrointestinal transit time and inhibit intestinal absorption, and we have therefore studied the effects of SMS 201–995 on these processes. Five male subjects received a test meal having been given either saline or 50 μg of SMS 201–995 subcutaneously 30 min before ingestion.
3. SMS 201–995 caused a delay in mouth-to-caecum transit time for lactulose assessed by breath hydrogen analysis (316 ± 17 vs 192 ± 14 min, mean ±sem, P &lt; 0.01), a delay (234 vs 120 min, P &lt; 0.05) in the plasma peak of the non-metabolizable glucose analogue 3-O-methylglucose and conversion of the expected postprandial rise in serum triglycerides (with saline 1.02 ± 0.20 to 1.51 ± 0.28 mmol/l, P &lt; 0.05) to a decrease below basal values (with SMS 201–995 0.97 ±0.80 to 0.79 ± 0.11 mmol/l, P &lt; 0.05).
4. After SMS 201–995, an enhancement of the increase in blood glucose (8.2 ±0.7 vs 4.7 ±0.2 mmol/l, P &lt; 0.01) and inhibition and postponement of the postprandial rise in insulin (27.6 ±6.7 vs 9.9 ±2.1 m-units/l, P &lt; 0.05) occurred. Furthermore, a rise in non-esterified fatty acids, glycerol and 3-hydroxybutyrate, compared with the decline in concentrations of these metabolites after saline, was observed.
5. We conclude that SMS 201–995 has actions to increase mouth-to-caecum transit time, to diminish the rate of active monosaccharide absorption and to lower basal and postprandial triglyceride levels. These effects probably relate to inhibition of exo- and endo-crine gastrointestinal secretion.
Mechanism of the postural vasoconstrictor response in the human foot
Authors: Hassan Ahmad A. K. , Tooke J. E. 
Published: August 2015

1. The mechanism of postural vasoconstriction in the skin of the foot was examined in 102 healthy subjects by using laser Doppler flowmetry.
2. In 45 subjects, when one foot was lowered 50 cm below heart level and the other foot kept horizontal, blood flow was progressively reduced in the dependent foot (by 79%) with a concomitant, but less pronounced, reduction in flow in the horizontal foot (by 18%), indicating that a central mechanism is involved. After lumbar sympathetic blockade (in 10 patients with epidural anaesthesia), the flow in the horizontal foot remained virtually constant, indicating that the central component is mainly mediated via efferent sympathetic nerves, whereas the postural fall in flow in the dependent foot, though partially attenuated, was preserved, indicating that a local mechanism is mainly involved.
3. On lowering one foot below heart level in 12 subjects, there was a small but significant reduction in systolic and mean arterial pressures during the first minute of dependency. During the fourth minute, systolic pressure decreased, diastolic pressure and heart rate increased, but the mean arterial pressure was maintained.
4. In 19 subjects postural vasoconstriction was nearly abolished during local nervous blockade (lignocaine 3.7 × 10−4–7.4 × 10−2 mol/l), indicating that the local mechanism mediating the vasoconstriction is mainly neurogenic in nature. However, there was still a small fall (19%) in flow in the dependent foot during blockade, probably indicating a minor contribution of a local myogenic mechanism.
5. In three subjects, application of venous occlusion of 40 mmHg with the foot at heart level reduced the flow by 63% at rest, and by only 12% during local nervous blockade, indicating that the increased venous pressure on dependency provides the main stimulus for postural vasoconstriction. However, a greater reduction in flow was observed in 13 subjects when the foot was lowered 50 cm below the heart (75%) than during venous occlusion of 40 mmHg (52%) with foot at heart level, indicating that not only the increase in venous pressure but also the increase in arterial transmural pressure is implicated in the postural increase in precapillary resistance.
6. It is concluded that postural vasoconstriction in the human foot is mainly produced by a local neurogenic mechanism with a small contribution from a local myogenic response, in addition to a centrally elicited sympathetic component.
Hyponatraemia in quadriplegic patients
Authors: Leehey David J. , Picache Alicia A. , Robertson Gary L. 
Published: August 2015

1. Studies were performed in five hyponatraemic (plasma sodium 129 ±1.6 mmol/l; plasma osmolality 268 ±3.0 mosmol/kg) quadriplegic patients in order to elucidate its aetiology. Five age- and sex-matched healthy subjects served as controls.
2. Daily urine volumes were high (4454 ± 624 ml) in the quadriplegic patients secondary to habitually increased fluid intake.
3. All quadriplegic patients had suppressed plasma arginine vasopressin levels (&lt; 0.8 pmol/l) and were able to form dilute urine after a water load (20 ml/kg). However, free water clearance and the ability to excrete the water load were frequently impaired, and these defects were associated with reductions in both osmolar clearance and delivery of filtrate to the distal diluting sites of the nephron.
4. During hypertonic saline (5%, w/v, NaCl) infusion, plasma arginine vasopressin rose progressively before plasma osmolality reached the normal range, consistent with a resetting of the osmostat.
5. We conclude that hyponatraemia in quadriplegic patients is related to an intrarenal defect in water excretion and resetting of the osmostat coupled with increased fluid intake.
Changes in glomerular filtration rate, lithium clearance and plasma protein clearances in the early phase after unilateral nephrectomy in living healthy renal transplant donors
Authors: Strandgaard S. , Kamper A. , Skaarup P. , Holstein-Rathlou N. H. , Leyssac P. P. , Munck O. 
Published: August 2015

1. Glomerular and tubular function was studied before and 2 months after unilateral nephrectomy in 14 healthy kidney donors by measurement of the clearances of 51Cr-labelled ethylenediaminetetra-acetate, lithium, β2-microglobulin, albumin and immunoglobulin G.
2. The glomerular filtration rate (GFR) of the kidney that remained in the donor rose from 45 ± 10 (mean ± sd) to 59 ± 10 ml/min (P &lt; 0.01) 5 days after contralateral nephrectomy and remained at this level through the observation period.
3. The lithium clearance (CLi) of the remaining kidney rose from 11.6 ± 3.7 to 20.5 ± 8.2 ml/min (P &lt; 0.01) and remained significantly elevated throughout the observation period.
4. Absolute proximal fluid reabsorption rate (APR), which was estimated as GFR minus CLi, was unchanged 5 days after contralateral nephrectomy, but then rose gradually to reach significantly elevated levels after 4 weeks.
5. Fractional proximal reabsorption (FPR; APR/GFR) fell from 0.75 ± 0.06 to 0.66 ± 0.11 (P &lt; 0.01) but subsequently rose to levels not significantly decreased from normal.
6. Twenty-four hour fractional clearances of β2-microglobulin, albumin and immunoglobulin G rose markedly on the day of nephrectomy, peaked at 2–3 days and subsequently fell to moderately elevated levels.
7. Both the CLj and the plasma protein clearance studies demonstrate that the early response of the remaining kidney to contralateral nephrectomy in man is an increase in GFR, an unchanged APR and a fall in FPR. The proximal tubules thus initially handle the increased filtrate load by passing it on to more distal nephron segments. Within 2–4 weeks, an adaptive increase is seen in proximal reabsorption of both protein and fluid, resulting in an almost complete normalization of glomerulotubular balance.