bluuebunny/crossref_metadata_2025_split huggingface dataset:
Increased arachidonic acid levels in phospholipids of human colonic mucosa in inflammatory bowel disease
Authors: Pacheco Sergio , Hillier Keith , Smith Colin 
Published: August 2015

1. Colonic mucosa from 19 patients with ulcerative colitis, eight with Crohn's disease and 14 controls were analysed for arachidonic acid (C20:4), linoleic acid (C18:2), oleic acid (C18:1), stearic acid (C18:0) and palmitic acid (C16:0).
2. Gas–liquid chromatography of lipid extracts showed that arachidonic acid was significantly higher in ulcerative colitis (19 ± 4) and Crohn's disease (20 ± 3) than in controls (13 ± 5 μg/mg of protein) (means ± sd). Neither the degree of inflammation nor treatment with sulphasalazine or prednisolone appeared to influence the fatty acid concentrations.
3. Seventy-five to ninety-five per cent of the arachidonic acid was found in the phospholipid fraction after separation by thin-layer chromatography. There were no significant changes in the concentrations of the other fatty acids measured, although oleic acid was lower in inflammatory bowel disease. The ratios of oleic acid to stearic acid and to palmitic acid were lower in inflammatory bowel disease.
4. The alteration in the fatty acid profile may partly explain the increased synthesis of eicosanoids in colonic mucosa in inflammatory bowel disease.
Increased bronchial reactivity to histamine in diabetic autonomic neuropathy
Authors: Rhind George B. , Gould Grahame A. , Ewing David J. , Clarke Basil F. , Douglas Neil J. 
Published: August 2015

1. Twelve male diabetic patients inhaled nebulized histamine in doubling concentrations from 0.03 mg/ml to 32 mg/ml until they reached the maximum concentration or until their forced expiratory volume in 1 s (FEV1.0) fell by at least 20%. Six had evidence of severe autonomic neuropathy (DAN), while the other six did not.
2. More of the DAN group decreased their FEV1.0 on histamine inhalation by at least 20% (P &lt; 0.02) and more of them decreased their maximal flow at 50% vital capacity by at least 20% than those in the group without DAN (P &lt; 0.05).
3. The fall in FEV1.0 and in maximal flow at 50% of vital capacity was greater (P &lt; 0.05) in the DAN group than in the group without DAN.
4. This suggests that diabetic patients with autonomic neuropathy have increased bronchial reactivity to histamine. This could either be due to differential damage of the respiratory autonomic nerves or, alternatively, to denervation hypersensitivity.
Voluntary isocapnic hyperventilation and breathlessness during exercise in normal subjects
Authors: Lane R. , Cockcroft A. , Guz A. 
Published: August 2015

1. Nine normal subjects performed 6 min, constant-workload, exercise tests on a bicycle ergometer at either a ‘high workload’ or at a ‘low workload’. During the first ‘high workload’ test their spontaneous breathing pattern was recorded on to magnetic tape. During one subsequent ‘high workload’ test and one ‘low workload’ test they voluntarily copied their recorded breathing pattern. During a second ‘low workload’ test they breathed spontaneously. Isocapnia was maintained by the operator throughout both the copying tests. During the exercise tests ventilation was recorded and subjects indicated the level of their sensation of breathlessness every 30 s.
2. Subjects felt markedly less breathless when a proportion of their ventilation was produced by voluntary effort than when the same total level of ventilation was produced entirely by the stimulus of exercise. Furthermore, voluntary isocapnic hyperventilation during exercise did not increase breathlessness above that normally associated with that level of exercise.
3. These results suggest that it is reflexly driven ventilation, and not simply the level of ventilation itself, which relates to the level of breathlessness during exercise.
Muscle strength in healthy White and Asian subjects: The relationship of quadriceps maximum voluntary contraction to age, sex, body build and vitamin D
Authors: Shaunak S. , Ang Liza , Colston Kay , Patel Swatee , Bland M. , Maxwell J. D. 
Published: August 2015

1. The maximum voluntary isometric contraction (MVC) of the dominant quadriceps muscle was measured in 136 healthy White and 172 healthy Hindu Asian subjects resident in London, using a specially designed chair equipped with a force measuring load cell.
2. Males were stronger than females, and for both sexes MVC declined with age. From age 20 to 60 the annual decline in MVC ranged from 0.56% in White males to 1.5% in female Asians.
3. White subjects were stronger than Asian subjects even after correcting for the effect of age, height, weight and sex in a multi-factorial analysis.
4. Only in males did MVC correlate with height and weight. Asian women were more obese than any other group, and showed an increase in body mass index with age.
5. Twenty-two per cent of Asian subjects had marked vitamin D deficiency (plasma 25-hydroxycholecalciferol &lt; 10 nmol/l). There was no correlation between MVC, and plasma 25-hydroxycholecalciferol.
Lithium clearance in man: Effects of dietary salt intake, acute changes in extracellular fluid volume, amiloride and frusemide
Authors: Atherton J. C. , Green R. , Hughes S. , McFall V. , Sharples J. A. , Solomon L. R. , Wilson L. 
Published: August 2015

1. The effects of amiloride and frusemide on lithium clearance were studied during changes in dietary sodium chloride intake and during infusion of 0.9% NaCl in normal human volunteers.
2. Lithium and fractional lithium clearances were less on the low than on the high salt diet. Values for the medium salt diet were intermediate. Acute extracellular fluid volume expansion with 0.9% NaCl infusion and extracellular fluid volume contraction 3–4 h after intravenous frusemide caused lithium and fractional lithium clearances to increase and decrease respectively.
3. Amiloride caused small changes in lithium and fractional lithium clearances on a low salt diet, but was without effect when salt intake was medium or high.
4. Increases in lithium clearance occurred immediately after frusemide irrespective of dietary salt intake and in subjects infused with 0.9% NaCl. Only in salt-depleted subjects did frusemide cause a substantial increase in fractional lithium clearance. Changes induced under other circumstances were small.
5. It is concluded that the lithium clearance method for assessment of proximal tubule salt and water re-absorption can be used with some degree of confidence in certain circumstances (medium and high salt intake as well as in acute volume expansion) but may not be reliable when dietary salt intake is low.
The effect of ketone bodies on leucine and alanine metabolism in dogs
Authors: Umpleby A. M. , Chubb D. , Boroujerdi M. A. , Sonksen P. H. 
Published: August 2015

1. The effect of an infusion of sodium β-hydroxybutyrate on leucine and alanine metabolism was investigated in dogs starved for 12 h. To determine whether the metabolic changes produced by this infusion were due to the resultant alkalaemia the effect of an equimolar infusion of sodium bicarbonate was also studied.
2. The sodium β-hydroxybutyrate infusion reduced alanine concentration as a result of a decrease in alanine production rate and an increase in alanine metabolic clearance rate. The sodium bicarbonate infusion induced a small decrease in alanine concentration which was due to an increased metabolic clearance rate. Alanine production rate showed no change. This demonstrates that the fall in alanine concentration after a sodium β-hydroxybutyrate infusion is due both to a ketone-specific inhibitory effect on alanine production rate and an increased metabolic clearance rate caused by the alkalaemia.
3. Leucine concentration was increased after the ketone infusion due to a small increase in production rate and there was a small increase in the rate of leucine incorporation into protein. Alkalaemia had no effect on leucine concentration or metabolism.
The strength, contractile properties and radiological density of skeletal muscle before and 1 year after gastroplasty
Authors: Newham D. J. , Harrison R. A. , Tomkins A. M. , Clark C. G. 
Published: August 2015

1. Skeletal muscle strength, contractile properties and radiological composition have been studied in seven morbidly obese adults (six female) before and 1 year after gastroplasty operations. The mean body weight fell from 138.3 kg (sd 25.2) to 99.7 kg (sd 23.0) (P &lt; 0.001).
2. The strength and contractile properties (force/frequency, relaxation rate and fatiguability) of both the adductor pollicis and quadriceps muscles were unaffected by the weight loss.
3. Computerized axial tomography scans obtained 1 year after surgery showed that the quadriceps contained an abnormally high proportion of fat. The mean fat content was 10.8% (range 3.0–30.1%) compared with 1.6% (range 0–5%) for normal muscle. Two individuals were scanned before and after surgery and the fat content of their quadriceps fell from 12.6% and 6.9% to 3.1% and 3.0%, respectively.
4. It is concluded that in obese individuals large amounts of weight can be lost, from both subcutaneous and intramuscular fat stores, without compromising either the strength or contractile properties of skeletal muscles. These results do not support the claim that skeletal muscle contractility is a sensitive indicator of changes in nutritional status.
Protein and substrate metabolism during starvation and parenteral refeeding
Authors: Tracey Kevin J. , Legaspi Adrian , Albert James D. , Jeevanandam Malayappa , Matthews Dwight E. , Brennan Murray F. , Lowry Stephen F. 
Published: August 2015

1. Healthy male volunteers underwent 10 days of hospitalized protein-calorie starvation and a subsequent 10 day repletion phase with complete intravenous nutritional support (IVF). Non-protein calories were provided as either all d-glucose or as 50% d-glucose/50% lipid.
2. In comparison with starvation, whole-body protein breakdown, as assessed by [15N]glycine, [13C]leucine and urinary excretion of 3-methylhistidine (3-MH), was diminished during IVF. The administration of parenteral nutrition did not specifically suppress peripheral tissue protein breakdown, as measured by extremity 3-MH efflux.
3. Despite the differential insulin response to d-glucose/amino acid (50 ± 6 m-units/ml) as compared with the d-glucose/lipid/amino acid regimen (25 ± 4 m-units/ml), there was no difference in nitrogen retention between the regimens. Indirect calorimetric determinations revealed that oxidation of substrate during IVF was related to the proportion of d-glucose and lipid infusion.
Naloxone increases mucosal fluid secretion in the inflamed and distended feline gall bladder: Evidence for a possible protective mechanism by endogenous opioids
Authors: Jivegård Lennart , Svanvik Joar 
Published: August 2015

1. Endogenous opioid peptides are found in the enteric nervous system in the gastrointestinal tract. The opioid peptide enkephalin, which has anti-secretory actions in the small intestine, is also contained in nerves in the gall-bladder wall.
2. In experimental cholecystitis, there is active fluid secretion by the epithelial cells into the gall-bladder lumen, when the intraluminal hydrostatic pressure is low. This fluid secretion to the lumen was abolished by intravenous administration of enkephalin, an effect that was blocked by naloxone pretreatment. The flux of fluid into the lumen was also abolished when the intraluminal hydrostatic pressure was raised to the level initially observed in the inflamed and obstructed gall bladder. Fluid absorption in the normal gall bladder was unaffected by enkephalin.
3. In experimental cholecystitis, naloxone, used as a non-specific antagonist of opiate action, did not affect the gall-bladder mucosal fluid transport observed at a low intraluminal hydrostatic pressure, but it induced fluid secretion when this pressure was high.
4. It is suggested that a raised intraluminal hydrostatic pressure in experimental cholecystitis, which distends the gall bladder, releases endogenous opioids that inhibit active fluid secretion by the gall-bladder epithelial cells. This response may represent a defence mechanism that could be present also in the gastrointestinal tract. In the obstructed and inflamed gall bladder it may prevent progressive distension, ischaemia and perforation of the wall.
A simple and rapid method for the determination of the concentrations of magnesium, sodium, potassium and sodium, potassium pumps in human skeletal muscle
Authors: Dørup Inge , Skajaa Kristjar , Clausen Torben 
Published: August 2015

1. For the diagnosis of electrolyte disorders, data on skeletal muscle composition are often valuable, but rarely available. We have therefore developed a simple and rapid needle biopsy procedure for the determination of the concentrations of K+, Na+, Mg2+ and Na+, K+-pumps in muscle.
2. Using a Bergström needle, biopsies weighing around 25 mg were taken from the vastus lateralis muscle of 18 normal subjects (aged 44–86 years) and extracted with trichloroacetic acid (TCA). The concentrations of K+, Na+ and Mg2+ were 90.7 ± 1.8, 31.9 ± 1.6 and 9.5 ± 0.2 μmol/g wet wt., respectively (means ± se).
3. The TCA extraction gave the same values as digestion with 65% HNO3 or 35% H2O2, could be used over the weight range 10–55 mg and showed a Mg2+ recovery of 101.7%.
4. The concentration of Na+, K+-pumps was quantified as the total capacity for [3H]ouabain binding. In vastus lateralis biopsies obtained from six normal subjects the mean value was 258 ± 16 pmol/g wet wt.
5. Comparison of the concentrations of K+, Mg2+ and [3H]ouabain-binding sites in samples obtained post mortem showed modest variation among different muscles with varying fibre composition.
6. Measurements of the concentrations of K+, Na+, Mg2+ and Na+, K+-pumps in duplicate biopsies of the vastus lateralis yield values which seem representative for the total pool of skeletal muscle fibres and can be performed within a few hours.
7. Measurements on patients receiving chronic diuretic treatment demonstrated that these procedures allow the detection of reduced levels of K+, Mg2+ and Na+, K+-pumps in skeletal muscle, as well as a partial recovery after oral Mg2+ supplementation.
Effect of single respiratory manoeuvres on specific airway conductance in heart–lung transplant recipients
Authors: Glanville Allan R. , Yeend Richard A. , Theodore James , Robin Eugene D. 
Published: August 2015

1. The time course and magnitude of the effect of single slow and rapid respiratory manoeuvres on specific airway conductance (sGaw) was assessed in seven normal control subjects and in seven heart–lung transplant (HLT) recipients before and after experimentally induced bronchoconstriction.
2. Neither full inspiration, full exhalation nor vital capacity manoeuvres significantly altered sGaw in normal controls or HLT recipients under baseline conditions despite the presence of hyper-responsiveness to methacholine (MC) in the latter group.
3. After induced bronchoconstriction, single slow and rapid inspirations to total lung capacity transiently abolished or attenuated the bronchoconstriction in normal controls. This effect was absent in the HLT recipients.
4. In HLT recipients, the combination of hyper-responsiveness to MC, the absence of bronchoconstriction with respiratory manoeuvres and the absence of significant bronchodilatation after deep inspiration suggest lack of normal pulmonary innervation.
Regulation of lactate uptake and lactate production in liver from 48-h-starved rats: Effects of pH, flow and glucose concentration
Authors: Sestoft Leif , Marshall Michael O. 
Published: August 2015

1. The effects of medium glucose concentration (0–20 mmol/l) and flow (100–33% of normal) on lactate uptake at low lactate concentration were studied in perfused livers from 48-h-starved rats with perfusate pH values of 7.4 and 6.8.
2. Lactate uptake was independent of glucose concentration in the range 5–10 mmol/l, but was slightly inhibited with time at 20 mmol/l glucose. This pattern was independent of perfusate pH.
3. At both pH values lactate uptake decreased proportionally with flow, and at low flow lactate was produced by the livers. The effect of flow was greatest at pH 7.4 where a net lactate production was found at 48% of normal flow, whereas at pH 6.8 lactate production was not seen until the flow was reduced to 33% of normal.
4. When glucose was omitted from the perfusate lactate production ceased at both pH values.
5. The effect of low pH on lactate uptake and production in liver probably reflects inhibition of glycolysis by low pH.
Atrial natriuretic peptide released by rapid ventricular pacing in dogs does not cause a natriuresis
Authors: Walsh K. P. , Williams T. D. M. , Canepa-Anson R. , Roe P. , Pitts E. , Lightman S. L. , Sutton R. 
Published: August 2015

1. The relationships between the haemodynamic, renal and endocrine changes induced by rapid ventricular pacing were studied in ten chloralose-anaesthetized dogs paced from the right ventricular apex for 60 min at 250 beats/min.
2. Pacing increased mean right atrial and mean pulmonary wedge pressure (P &lt; 0.05), and decreased cardiac output and mean arterial pressure (P &lt; 0.05).
3. Coronary sinus atrial natriuretic peptide (ANP) concentrations were approximately fourfold greater than arterial concentrations; both increased markedly during pacing (P &lt; 0.01). Plasma concentrations of arginine vasopressin and plasma renin activity did not change signficantly.
4. Urine flow and free water clearance increased during the latter 30 min of pacing (P &lt; 0.05). There was no significant change in sodium clearance despite high sustained concentrations of ANP.
5. Without the availability of specific inhibitors of ANP release or action, we are unable to exclude the possibility that ANP may have prevented sodium clearance from otherwise decreasing during rapid ventricular pacing. Nevertheless, the dissociation between elevated ANP concentrations and natriuresis in this study indicates that a rise in ANP concentrations per se is not sufficient to produce a natriuresis.
Reciprocal change, exercise-induced ST segment depression and coronary anatomy: Are they related in the post-infarct patient?
Authors: Murray Donal P. , Tan Lip Bun , Salih Mahmood , Weissberg Peter , Murray R. Gordon , Littler William A. 
Published: August 2015

1. The relationship of reciprocal change on the electrocardiogram, at the time of acute myocardial infarction, to exercise-induced ST segment depression and coronary anatomy was studied in 125 post-infarct patients.
2. Eighty-three patients had reciprocal changes, 90 had exercise-induced ST depression and 72 had both of these findings.
3. Patients with reciprocal changes had larger myocardial infarctions, as assessed by peak enzyme release and ejection fraction, than patients without this finding.
4. Multi-vessel disease was significantly more common among patients with reciprocal changes and those with exercise-induced ST depression compared with patients without these findings.
5. The exercise test was more sensitive and had a higher predictive accuracy than reciprocal change when electrocardiographic changes were compared with findings at coronary angiography.
6. With both tests the antero-lateral leads were significantly more sensitive, but less specific, than the inferior leads in classifying patients.
7. Thus while both tests yielded information with regard to coronary anatomy in post-infarct patients, the exercise test was a better predictor of coronary anatomy than reciprocal change.
8. Therefore, reliance should not be placed on the presence or absence of reciprocal change alone when assessing patients for further investigation after myocardial infarction.
Neutrophil chemotaxis in bronchiectasis: A study of peripheral cells and lung secretions
Authors: Stockley R. A. , Shaw J. , Hill S. L. , Burnett D. 
Published: August 2015

1. Some bronchiectatic patients persistently expectorate purulent secretions containing many polymorphonuclear leucocytes (PMN) and bacteria, suggesting ineffective microbial clearing from the lung. We have therefore studied several aspects of PMN recruitment to the lung by chemotaxis.
2. Circulating PMN from patients with bronchiectasis show a variable chemotactic response to the synthetic peptide N-formyl-l-methionyl-l-leucyl-l-phenylalanine. This is similar to the response of PMN from healthy controls and suggests that failure to clear microbial organisms is not due to defective chemotaxis as measured here.
3. Purulent sputum solphase demonstrates chemotactic activity against control PMN. This activity is greater (P &lt; 0.001) than that found with mucoid sputum solphase, which is consistent with the neutrophil content of the secretions in vivo.
4. Successful antibiotic therapy reduces the chemotactic activity of purulent sputum solphase from a median value of 183 (range 28–201) cells/high power field to 33.5 (range 0.7–64) cells/high power field (P &lt; 0.0025). This indicates that the chemotactic activity is largely associated with bacterial load.
Calcium retention and increased vascular reactivity caused by a hypothalamic sodium transport inhibitor
Authors: Afzal Mir M. , Morgan Kevin , Chappell Stephen , Lewis Mark , Spurlock Gillian , Collins Peter , Collins Philip , Lewis Malcolm , Scanlon Maurice 
Published: August 2015

1. Using a previously established method of isolating an active-sodium-transport inhibitor (ASTI) from hypothalamic cell culture medium, the inhibitor was isolated and partially purified from sequential passages through Sephadex G-25 and h.p.l.c, and its effects on de-endothelialized rabbit aortic strips were investigated.
2. ASTI caused a cumulative concentration-dependent increase in tension which reversed slowly after wash, and the wash showed an identical effect on fresh strips.
3. Ouabain, used as a control, also caused a concentration-dependent increase in tension which reached a plateau at a concentration of 10 mmol/l. Both ouabain and ASTI caused a significant potentiation of the vasoconstrictor effect of noradrenaline at concentrations of 1 nmol/l-0.1 mmol/l.
4. Both ASTI and ouabain caused a significantly greater (P &lt; 0.01) calcium retention than control medium in aortic strips.
5. Incubation of ASTI with prolidase, chymotrypsin and carboxypeptidase A destroyed the vasoconstrictor effects as well as its inhibitory effects on sodium, potassium-dependent adenosine triphosphatase and sodium efflux from erythrocytes, but leucine aminopeptidase was ineffective.
6. These studies suggest that hypothalamic cells in culture release a peptidic inhibitor of active sodium transport which increases vascular reactivity, potentiates vasoconstrictor effects of noradrenaline and causes calcium retention.