bluuebunny/crossref_metadata_2025_split huggingface dataset:
Human Gastrin and Vasoactive Intestinal Polypeptide Responses to Endurance Running in Relation to Training Status and Fluid Ingested
Authors: MacLaren D. P. , Raine N. M. , O'Connor A. M. , Buchanan K. D. 
Published: August 2015

1. Plasma concentrations of gastrin, glucose, vasoactive intestinal polypeptide and non-esterified fatty acid were analysed in six male endurance runners and six male hockey players before, during and 15 min after 90 min treadmill running at 65% maximum oxygen uptake under two conditions: no fluid ingestion (trial A) and ingestion of 8% maltodextrin solution (trial B).
2. Exercise resulted in significantly elevated plasma gastrin concentrations compared with resting values in both groups after trial A (endurance runners, 69.4 ng/l; hockey players 71.4 ng/l) and trial B (endurance runners, 105.5 ng/l; hockey players, 83.2 ng/l). The gastrin response was not significantly different between the trials.
3. Plasma vasoactive intestinal polypeptide levels increased significantly beyond resting levels for both groups during trial A (endurance runners, 76.1 ± 53.7 ng/l; hockey players 155.6 ± 41.9 ng/l) and trial B (endurance runners 47.5 ± 21.3 ng/l; hockey players 132.9 ± 43.9 ng/l). The vasoactive intestinal polypeptide response to trial B was significantly attenuated compared with trial A.
4. There were no significant differences between endurance runners and hockey players for plasma gastrin, although hockey players produced significantly elevated concentrations of plasma vasoactive intestinal polypeptide after both trials compared with endurance runners.
5. Plasma glucose levels throughout trial B were significantly greater than after trial A irrespective of the group. Plasma glucose concentrations were not significantly different between endurance runners and hockey players.
6. Plasma non-esterified fatty acid concentrations rose significantly for both groups throughout exercise. Trial B resulted in an attenuated non-esterified fatty acid response compared with trial A.
7. No significant relationships were identifed between metabolite and gastrointestinal hormone concentrations, or between maximum oxygen uptake and the hormonal response to exercise.
8. These results highlight the attenuating role of carbohydrate fluid ingestion and level of aerobic fitness in the responses of plasma vasoactive intestinal polypeptide during prolonged exercise, whereas plasma gastrin is not significantly affected by either.
Sympathetic Stimulations by Exercise-Stress Testing and by Dobutamine Infusion Induce Similar Changes in Heart Rate Variability in Patients with Chronic Heart Failure
Authors: Piepoli Massimo , Adamopoulos Stamatis , Bernardi Luciano , Sleight Peter , Coats Andrew J. S. 
Published: August 2015

1. Heart rate variability can be used to evaluate autonomic balance, but it is unclear how inotropic therapy may affect the findings. The aim of the study was to assess whether heart rate variability can differentiate between sympathetic stimulation induced by inotrope infusion or by physical exercise.
2. Ten patients with chronic heart failure (64.3 ± 5.4 years of age) underwent four dobutamine infusions (8-min steps of 5 μg min−1 kg−1) and four supine bicycle exercise tests (5-min steps of 25 W). Plasma noradrenaline was evaluated, as well as the SD of R—R intervals, together with low-frequency (0.03–0.14 Hz) and high-frequency (0.15–0.4 Hz) components of heart rate variability using autoregressive spectral analysis.
3. Exercise and inotrope infusion produced similar changes in heart rate variability. An exercise load of 50 W and a dobutamine infusion of 15 μg min−1 kg−1 gave the following results respectively: heart rate, 120.3 ± 3.0 beats/min versus 110.2 ± 3.0 beats/min; SD, 16.0 ± 1.1 ms versus 16.3 ± 2.5 ms; low-frequency component, 4.3 ± 0.3 ln-ms2 versus 4.4 ± 0.3 ln-ms2 and high-frequency component, 2.6 ± 0.3 ln-ms2 versus 2.2 ± 0.3 ln-ms2. All comparisons were non-significant. The variables of heart rate variability showed high reproducibility in the same subject during different conditions. Noradrenaline was elevated by exercise from 326.0 ± 35.2 pg/ml to 860.1 ± 180.4 pg/ml (P &lt; 0.05), but was unchanged by dobutamine infusion.
4. Heart rate variability changes cannot differentiate between dobutamine infusions and physical exercise, indicating that we should be cautious in evaluating patients undergoing inotropic therapy. The degree of receptor stimulations, rather than the level of sympathetic drive, would appear to determine the changes in heart rate variability.
Effects of Maternal Diabetes on Blood Pressure and Glucose Tolerance in Offspring of Spontaneously Hypertensive Rats: Relation to Birth Weight
Authors: Iwase Masanori , Wada Miya , Wakisaka Masanori , Yoshizumi Hideyuki , Yoshinari Mototaka , Fujishima Masatoshi 
Published: August 2015

1. We studied the effects of maternal diabetes on blood pressure and glucose tolerance in the adult female offspring of spontaneously hypertensive rats.
2. Female spontaneously hypertensive rats were rendered diabetic by neonatal streptozotocin treatment, and then were mated with untreated male spontaneously hypertensive rats. Moderately severe hyperglycaemia was maintained during the gestation.
3. The birth weight was significantly lower in the female offspring of the diabetic dams than in the female offspring of the non-diabetic dams. The systolic blood pressure was significantly higher in the offspring from the diabetic dams than that from the control dams at 6 months of age (192 ± 4 mmHg versus 213 ± 4 mmHg, P &lt; 0.01). The heart weight was also significantly increased in the offspring of the diabetic dams. Both the blood pressure and heart weight were inversely related to the birth weight. On the other hand, glucose tolerance was unaffected by maternal diabetes.
4. Maternal diabetes aggravated the severity of hypertension in the adult female offspring of spontaneously hypertensive rats. This suggests the importance of the metabolic environment during fetal growth for the development of hypertension.
Isogravitational Heterogeneity of Perfusion after Unilateral Lung Transplantation
Authors: Ross D. J. , Koerner S. K. , Elashoff J. , Waxman A. D. , Mohsenifar Z. 
Published: August 2015

1. Single-photon emission computerized tomography in both an intact canine model and man has demonstrated an aspect of pulmonary perfusion to be independent of gravitational forces.
2. Using technetium 99 m-labelled macroaggregated albumin single-photon emission computerized tomographic imaging, we investigated normal human subjects (n = 5), stable unilateral lung transplant recipients (n = 6) and transplant recipients with chronic allograft dysfunction related to obliterative bronchiolitis (n = 5).
3. In coronal isogravitational sections, a 1 × 1 × N pixel strip (medial to lateral) was constructed through the ‘core’ pixel of maximal radioactive counts. The counts were measured for the ‘core’ pixel and at two mid-points (medial and lateral) between the core pixel and the lung edges. Coefficients of variation were computed for each isogravitational strip and compared between groups. Fractional whole-lung perfusion was determined for left versus right lungs of normal subjects and allograft versus native lungs of transplant recipients.
4. Using these indices, ‘isogravitational heterogeneity’ (i.e. increased ‘core’ versus peripheral perfusion) was observed in allografts and native diseased lungs after unilateral transplantation. Despite significantly increased fractional whole-lung perfusion directed to the allografts (84.8% ± 3.0% and 75.8% + 12.1% for stable unilateral lung transplant recipients and patients with obliterative bronchiolitis respectively) compared with normal lungs (50.2% ± 1.2% and 49.8% ± 1.2% for left and right respectively), ‘isogravitational flow heterogeneity’ (i.e. increased ‘core’ versus peripheral perfusion) was preserved after transplantation.
5. These findings suggest that ‘isogravitational heterogeneity’ was maintained despite increased unilateral pulmonary perfusion and the presumed increase in pulmonary capillary recruitment and/or distension.
Effect of the Transmembrane Gradient of Magnesium and Sodium on the Regulation of Cytosolic Free Magnesium Concentration in Human Platelets
Authors: Yoshimura Mitsuisa , Oshima Tetsuya , Matsuura Hideo , Watanabe Mitsuaki , Higashi Yukihito , Ono Norihisa , Hiraga Hiroyuki , Kambe Masayuki , Kajiyama Goro 
Published: August 2015

1. To clarify the mechanism by which cytosolic free Mg2+ concentrations ([Mg2+]i) are regulated in human platelets, we investigated platelet membrane permeability to Mg2+ by altering extracellular Mg2+ concentrations, and tested the existence of a Na+-Mg2+ exchanger by manipulating the transmembrane Na+ gradient.
2. Platelet [Mg2+], was 421 ± 52 μmol/l in healthy men. [Mg2+]; remained constant during a 120 min exposure to nominally zero (low) or 5 mmol/l (high) external Mg2+ concentrations.
3. Preincubation of platelets with 10−4 mol/l ouabain effectively decreased the transmembrane Na+ gradient. The ouabain-induced increase in [Mg2+], was statistically significant after 30 min of exposure (14.6 ± 2.0%) and reached 24.6 ± 4.5% after 60 min. Similarly, the replacement of extracellular Na+ with N-methyl-d-glucamine significantly increased [Mg2+]i by 48.5 ± 3.9% and 78.8 ± 12.5%, respectively.
4. These results suggest that [Mg2+]i is well controlled in the presence of large transmembrane Mg2+ concentration gradients, and a Na+-Mg2+ exchanger may be involved in the regulation of [Mg2+]i in human platelets.
Effect of Water-Loading on the Performance of Polyethylene Glycol as a Marker of Small Intestinal Permeability
Authors: Iqbal Tariq H. , Cox Mark A. , Lewis Kenneth O. , Cooper Brian T. 
Published: August 2015

1. Polyethylene glycol has been used extensively to measure small intestinal permeability in vivo. However, polyethylene glycol seems to traverse the intestinal mucosa in much greater quantities than sugar molecules of equivalent Mr. In addition, the recovery of the lowest Mr polymers of administered polyethylene glycol has been found to be both low and unreliable.
2. To compare the behaviour of a range of polyethylene glycol polymers with sugar probes in vivo, a combined polyethylene glycol/mannitol/lactulose probe was administered sequentially to healthy individuals in the fasted state and under conditions of water-loading. Timed hourly urine collections were made for 6 h.
3. Mannitol and lactulose recoveries were all within the normal range and were unaffected by coadministration of water. The lactulose/mannitol recovery ratios did not vary significantly over the 6 h collection period. In contrast, the recovery of total polyethylene glycol was significantly greater when subjects were water-loaded. Futhermore, proportionally greater quantities of polyethylene glycol Mr 370 than Mr 854 were recovered towards the end of the collection period than at the start.
4. Our results show that, in contrast to lactulose and mannitol, excretion of low—medium Mr polyethylene glycol polymers is highly dependent on coadministration of water. Futhermore, the differential rate of excretion of the low compared with the high Mr polyethylene glycol polymers suggests that the volume of distribution of the individual polymers may vary with Mr, and smaller polyethylene glycol molecules may undergo considerable renal tubular reabsorption.
Protein Synthesis in Isolated Enterocytes from Septic or Endotoxaemic Rats: Regulation by Glutamine
Authors: Higashiguchi Takashi , Noguchi Yoshifumi , Meyer Tory , Fischer Josef E. , Hasselgren Per-Olof 
Published: August 2015

1. We studied the effect of sepsis and the regulation by glutamine of protein synthesis in enterocytes isolated from the small intestine of rats.
2. Sepsis was induced by caecal ligation and puncture; control rats were sham operated. Enterocytes were isolated from the jejunum and incubated in a medium containing [3H]phenylalanine.
3. Sixteen hours after caecal ligation and puncture, protein synthesis, measured as incorporation of radioactivity into protein, was increased by 65%, 89% and 137% respectively in enterocytes from the tips and mid-portions of the villi and from the crypts.
4. Addition of glutamine to incubated enterocytes stimulated protein synthesis in a dose-dependent manner, and this effect was most pronounced in crypt cells from septic rats. The effect of glutamine on protein synthesis was duplicated by equimolar concentrations of acetoacetate or 3-hydroxybutyrate, both of which may serve as fuel for enterocytes, and was blocked by the glutaminase inhibitor 6-diazo-5-oxo-l-norleucine.
5. The results suggest that sepsis stimulates protein synthesis in enterocytes and that glutamine regulates protein synthesis in the same cells, probably by energy provision.
Antecedent Hypoglycaemia in Non-Diabetic Subjects Reduces the Adrenaline Response for 6 Days but Does Not Affect the Catecholamine Response to other Stimuli
Authors: Robinson A. M. , Parkin H. M. , MacDonald I. A. , Tattersall R. B. 
Published: August 2015

1. Recent hypoglycaemia reduces the counter-regulatory and symptomatic response to the next episode of hypoglycaemia. This study was designed to determine whether antecedent hypoglycaemia (a) affected the sympathoadrenal response to other stimuli (postural change and a mathematical stress test, (b) was associated with adaptation of cognitive function and (c) if avoided for 6 days led to the restoration of the counter-regulatory response to hypoglycaemia.
2. On the morning of day 1, 10 healthy men had their response to the sympathoadrenal stimuli assessed before an episode of hypoglycaemia (2.5 mmol/l). A further hyperinsulinaemia clamp was performed for 2 h (blood glucose 3.0 mmol/l or 5.0 mmol/l) in the afternoon and the assessments repeated the next day and 6 days later. Cognitive function using the four-choice reaction time test was assessed before and during the episodes of morning hypoglycaemia. The whole study was repeated 4 weeks later with the other afternoon glucose level.
3. Adrenaline levels and sweat rates were reduced (P &lt; 0.05) on day 2 during hypoglycaemia on both occasions and had not returned to normal after 6 days. Symptom scores were lower (P &lt; 0.05) only on day 2 after the afternoon of hypoglycaemia. The responses to the sympathoadrenal stimuli and cognitive function were unaffected by antecedent hypoglycaemia.
4. The adaptation of the counter-regulatory response to antecedent hypoglycaemia appears to be specific to hypoglycaemia. The response takes longer than 6 days but less than 4 weeks to return to normal. Antecedent hypoglycaemia does not lead to cerebral adaptation.
High-Affinity Interaction of Long-Chain Fatty Acids with Serum Albumin in Nephrotic Syndrome
Authors: Lerique Brice , Moulin Bruno , Delpero Claude , Purgus Rajsingh , Olmer Michel , Boyer Jean 
Published: August 2015

1. We have examined the effect of hypoalbuminaemia, a hallmark of nephrotic syndrome, on the albumin—fatty acid equilibrium in the plasma of 11 adult patients with nephrosis compared with 12 healthy subjects and six subjects with normoalbuminaemic hyperlipoproteinaemia.
2. We used a dialysis exchange rate method which allows the evaluation in relative terms of the binding affinity of albumin for plasma fatty acid and the fatty acid availability, tentatively equated with the unbound fatty acid fraction.
3. In nephrotic patients, an increase (P &lt; 0.001) in albumin affinity for fatty acid was seen compared with healthy subjects, which was negatively correlated with albuminaemia (r = −0.69, P &lt; 0.02). No change in fatty acid availability was seen for the group as a whole, but individual values showed a wide scatter, with the highest values in four patients with the highest fatty acid-albumin molar ratios. The increase in albumin affinity for fatty acid was specific to nephrotic syndrome since no such effect was seen in subjects with hyperlipoproteinaemia, who only showed a moderate increase (P &lt; 0.01) in fatty acid availability.
4. The increased albumin affinity for fatty acid in nephrotic syndrome supports the hypothesis that an albumin component with lower affinity for fatty acid might filter out through the diseased glomerular membrane and leave the high-affinity albumin in plasma.
Effects of Treadmill Exercise and High-Fat Feeding on Muscle Degeneration in Mdx Mice at the time of Weaning
Authors: Mokhtarian Asghar , Lefaucheur Jean Pascal , Even Patrick C. , Sebille Alain 
Published: August 2015

1. Dystrophin-deficient hindlimb muscles of mdx mice undergo necrosis at the time of weaning when the motor activity of the mice greatly increases and muscle energy metabolism becomes more dependent on insulin and carbohydrates.
2. We have attempted to determine if the onset of myofibre necrosis in mdx mice at the time of weaning is related to the development of motor activity and/or the change in diet.
3. Fourteen-day-old mdx mice were divided into two groups after weaning. One group was trained to run on a treadmill and the other group was kept on a high-fat diet. Muscle necrosis was assessed histologically in the soleus and extensor digitorum longus muscles of mice in both experiments.
4. Keeping mice on a high-fat milk diet from the time of weaning up to 42 days of age did not influence the occurrence of necrosis in the soleus and extensor digitorum longus muscles of the mdx pups. In contrast, treadmill exercise greatly increased necrosis in both muscles.
5. We conclude that an increase in motor activity exacerbates the degeneration of hindlimb muscles of mdx mice at the time of weaning.
Microvascular Response to Tissue Injury and Capillary Ultrastructure in the Foot Skin of Type I Diabetic Patients
Authors: Rayman G. , Malik R. A. , Sharma A. K. , Day J. L. 
Published: August 2015

1. Microvascular blood flow responses to injury and capillary ultrastructure were assessed by laser Doppler flowmetry and detailed light and electron microscopy respectively in skin biopsied from 28 patients with insulin-dependent diabetes and 17 control subjects.
2. The hyperaemic response induced by biopsy (P &lt; 0.001) and heating to 44°C (P &lt; 0.001) was significantly lower in the diabetic patients and showed progressive impairment with the severity of complications (P &lt; 0.001).
3. Skin capillary basement membrane thickness was significantly increased in the diabetic patients (P &lt; 0.001) and also increased with the severity of complications (P &lt; 0.002). Both the luminal area (P &lt; 0.001) and the endothelial cell outer perimeter (P &lt; 0.002), measures of luminal and capillary size, respectively, were significantly reduced in all diabetic patients.
4. Basement membrane thickness was related significantly to the impaired hyperaemic response to both biopsy (P &lt; 0.01) and thermal injury (P &lt; 0.01).
5. Our findings support the hypothesis that structural abnormalities, which are characterized by an early reduction in capillary size and later thickening of basement membrane, form an important mechanism for the impaired hyperaemic response in diabetic patients.
Clinical Remission is Associated with Restoration of Normal High-Density Lipoprotein Cholesterol Levels in Children with Malignancies
Authors: Dessì Sandra , Batetta Barbara , Spano Ornella , Sanna Francesca , Tonello Mauro , Giacchino Mareva , Tessitore Luciana , Costelli Paola , Baccino Francesco M. , Madon Enrico , Pani Paolo 
Published: August 2015

1. Serum lipids and lipoprotein profiles were determined in children affected by different types of malignancies (leukaemias or lymphomas and solid tumours) both before any treatment and after remission of the disease following chemical or surgical therapy.
2. At the time of diagnosis, children bearing tumours showed hypertriglyceridaemia and reduced concentrations of plasma high-density lipoprotein cholesterol levels, the decrease being particularly prominent in patients with haematological tumours. Children bearing solid tumours displayed an increase of total cholesterol, while those with haematological cancer showed decreased phospholipid levels; low-density lipoprotein cholesterol in neoplastic patients was not significantly different from control values. High triacylglycerol and low high-density lipoprotein cholesterol levels were also evident in cancer patients divided according to age into three groups (0–5, 6–10 and 11–15 years) when compared with age-matched control subjects. Similarly, high triacylglycerol and low high-density lipoprotein cholesterol levels were also observed in both male and female children when patients were divided according to sex and compared with corresponding controls.
3. Clinical remission after therapy was accompanied by an increase of high-density lipoprotein cholesterol levels compared with values observed at diagnosis. In contrast, post-treatment levels of triacylglycerol were higher than those observed before therapy. These results support the hypothesis that alterations of high-density lipoprotein cholesterol levels may be related, at least in part, to the rate of tumour growth, while modifications of triacylglycerol levels may be mediated by different mechanisms.
Intracolonic Release in Vivo of Interleukin-1β in Chronic Ulcerative Colitis
Authors: Casellas Francesc , Papo Michel , Guarner Francisco , Antolín María , Segura Rosa María , Armengol José Ramón , Malagelada Juan-Ramón 
Published: August 2015

1. To investigate the role of interleukin-1β in chronic ulcerative colitis, we quantified interleukin-1β steady-state release into the colonic lumen.
2. We studied 26 patients with untreated chronic ulcerative colitis and seven patients with irritable bowel syndrome who served as disease controls. In seven ulcerative colitis patients, the disease was inactive and in 19 it was mild to moderately active, according to clinical and colonoscopic criteria. Seven patients with active colitis were studied before and after 4 weeks of treatment with oral 5-aminosalicylic acid.
3. Colonic perfusions were performed using a double-lumen technique. An isotonic solution was continuously infused 50 cm from the anal verge at 5 ml/min, and was recovered 30 cm distally by siphonage. Interleukin-1β was measured by ELISA, polymorphonuclear elastase by immunoactivation and leukotriene B4 by specific RIA.
4. All control patients and five out of seven patients with inactive colitis had undetectable interleukin-1β release. In active colitis, the release of interleukin-1β was detected in 17 out of 19 patients (median 500 pg/min, interquartiles 270–1582 pg/min, P &lt; 0.01 compared with control subjects and patients with inactive colitis). Elastase and leukotriene B4 release were also significantly increased in active colitis compared with inactive colitis and controls. Leukotriene B4 release was similar in inactive colitis and controls, whereas elastase release was higher in inactive colitis than in controls. Five out of seven patients with colitis improved after treatment with 5-aminosalicylic acid. In all responder patients, interleukin-1β became undetectable or declined.
5. Our results demonstrate under conditions in vivo that active colitis is associated with enhanced interleukin-1β release into the colonic lumen whereas such release does not occur in remission, supporting the concept that ulcerative colitis flare-ups involve increased interleukin-1β production.