bluuebunny/crossref_metadata_2025_split huggingface dataset:
Accuracy of Breath-by-Breath Analysis of Flow-Volume Loop in Identifying Sleep-Induced Flow-Limited Breathing Cycles in Sleep Apnoea-Hypopnoea Syndrome
Authors: Sériès Frédéric , Marc Isabelle 
Published: August 2015

1. Inspiratory flow limitation is involved in the pathophysiology of sleep-related breathing disorders. Since the definition of flow-limited cycle is based on a dissociation between flow and respiratory efforts, identification of inspiratory flow limitation requires upper airway or intrathoracic pressure measurements. We examined the accuracy of the analysis of the flow—volume loop of a tidal breath in identifying inspiratory flow limitation during sleep in ten patients with a sleep apnoea—hypopnoea syndrome.
2. Measurements were taken during continuous positive airway pressure trials. After data acquisition, the presence of inspiratory flow limitation was identified by the presence of an inspiratory plateau or decrease in inspiratory flow independently of the increase in inspiratory efforts. The flow—volume loop was reconstructed for each breathing cycle by plotting the instantaneous flow and the tidal volume. The instantaneous inspiratory and expiratory flows were measured at 50% of the respective portion of the tidal volume, and a breath-by-breath analysis of the midtidal volume—flow ratio (inspiratory/expiratory ratio) was obtained. The analysis of the flow—volume loop was compared with standard inspiratory flow limitation criteria using different values of the inspiratory/expiratory ratio threshold, below which breathing cycles were classified as flow-limited. With a lower limit of the normal inspiratory/expiratory ratio threshold of 0.97, the sensitivity and specificity of the method were both 76%. In each subject, the proportion of breathing cycles identified as flow-limited according to the inspiratory/expiratory ratio progressively decreased with an increasing positive pressure level.
3. We conclude that analysis of the flow—volume curve is accurate in identifying most of the inspiratory flow limitation breathings in sleep apnoea—hypopnoea syndrome.
Biosynthesis of Platelet-Activating Factor in Normal and Inflamed Human Colon Mucosa: Evidence for the Involvement of the Pathway of Platelet-Activating Factor Synthesis De Novo in Inflammatory Bowel Disease
Authors: Appleyard Caroline B. , Hillier Keith 
Published: August 2015

1. Platelet-activating factor can be synthesized by two distinct biochemical pathways and is degraded by a number of enzymes, the first step of which is deacetylation by a specific acetyl hydrolase.
2. The biochemical pathway of platelet-activating factor synthesis de novo and the first step in platelet-activating factor degradation have been investigated for the first time in incubates of normal human colon mucosa and in inflamed mucosa from patients with inflammatory bowel disease.
3. In the presence of 100 μmol/l CDP-choline and 100 μmol/l hexadecyl acetyl glycerol, homogenates from inflamed mucosa synthesized significantly greater platelet-activating factor [851 ± 574 pmol/mg of protein (mean ± SEM) in 90 min incubation] than normal mucosa [105 ± 61 pmol/mg of protein in 90 min incubation] (P &lt; 0.05).
4. Under the same conditions of assay, the percentage turnover to inactive lyso-platelet-activating factor was similar in inflamed mucosa (35.5 ± 9.4%) and normal mucosa (42.7 ± 8.5%) in 90 min (P &gt; 0.05).
5. The identity of platelet-activating factor was confirmed by HPLC, by its mobility on TLC and by the ability of WEB 2170, a selective platelet-activating factor receptor antagonist, to block its platelet-aggregatory action.
6. These findings confirm the presence of the pathway for the synthesis de novo of the potently proinflammatory platelet-activating factor in human colon mucosa in inflammatory bowel disease.
Use of a Stable Copper Isotope (65Cu) in the Differential Diagnosis of Wilson's Disease
Authors: Lyon T. D. B. , Fell G. S. , Gaffney D. , McGaw B. A. , Russell R. I. , Park R. H. R. , Beattie A. D. , Curry G. , Crofton R. J. , Gunn I. , Sturniolo G. S. , D'inca R. , Patriarca M. 
Published: August 2015

1. 65Cu/63Cu stable-isotope ratios have been measured in blood serum after oral administration of the stable isotope 65Cu. The incorporation of the isotope into the plasma protein pool was followed at various times for up to 3 days. The resulting patterns of enrichment in healthy control subjects, in Wilson's disease patients and in heterozygotes for the Wilson's disease gene, were similar in appearance to those found by others using copper radioactive isotopes. After an initially high enrichment at 2h after dosage, the Wilson's disease cases, in contrast to the control subjects, did not show a secondary rise in isotope enrichment of the plasma pool after 72 h, demonstrating a failure to incorporate copper into caeruloplasmin. The Wilson's disease heterozygotes had variable degrees of impairment of isotope incorporation, not always distinguished from those of control subjects.
2. The stability of the isotope also permits the copper tracer to be followed for a longer period. Ten healthy subjects were studied for over 40 days, allowing the biological half-time of an oral dose of copper to be determined (median 18.5 days, 95% confidence interval 14–26 days). Known heterozygotes for the Wilson's disease gene were found to have a significantly increased biological half-time for removal of copper from the plasma pool (median 43 days, 95% confidence interval 32–77 days).
3. The incorporation of 65Cu in patients with diseases of the liver (other than Wilson's disease) was found to be similar to that in control subjects, aiding differential diagnosis.
Type I Collagen Biosynthesis by Skin Fibroblasts from Patients with Idiopathic Juvenile Osteoporosis
Authors: Pocock Andrew E. , Francis Martin J. O. , Smith Roger 
Published: August 2015

1. Skin fibroblast lines were cultured from nine patients who had the features of idiopathic juvenile osteoporosis, six relatives, five unrelated control subjects and three unrelated patients with osteogenesis imperfecta type I. Some patients with idiopathic juvenile osteoporosis were adults whose previous osteoporosis was in remission. Two patients with idiopathic juvenile osteoporosis were siblings and one patient with idiopathic juvenile osteoporosis had a daughter with severe osteogenesis imperfecta (type III).
2. The ratio of type III to type I collagen, synthesized by fibroblasts, was increased in two of the patients with osteogenesis imperfecta type I and in the daughter with osteogenesis imperfecta type III, but was normal in all the other patients with idiopathic juvenile osteoporosis and the other relatives.
3. Radiolabelled collagen was digested by cyanogen bromide and separated on SDS-PAGE. Unreduced collagen peptides migrated normally, except those from both the two siblings with idiopathic juvenile osteoporosis. In these two lines, abnormal migration suggested the presence of collagen I mutations.
4. The secretion of synthesized collagen by these two idiopathic juvenile osteoporosis lines and two others was reduced to only 43–45% as compared with a line from a 13-year-old control subject, which was defined as 100%. The three osteogenesis imperfecta type I lines secreted 18–37%, the other five idiopathic juvenile osteoporosis lines secreted 57–75%, the relatives (including the daughter with severe osteogenesis imperfecta) secreted 49–115% and the controls secreted 69–102%.
5. We conclude that qualitative abnormalities of type I collagen associated with a reduction in total secreted collagen synthesis may occur in a minority of patients with idiopathic juvenile osteoporosis; these patients could represent a subset of patients with this disorder.
Lipopolysaccharide Induces Upregulation of Neutral Endopeptidase 24.11 on Human Neutrophils: Involvement of the CD14 Receptor
Authors: Fagny Christine , Marchant Arnaud , De Prez Eric , Goldman Michel , Deschodt-Lanckman Monique 
Published: August 2015

1. As lipopolysaccharide is a major stimulator of neutrophil responses during Gram-negative bacterial infections, we studied its effect on the membrane expression of neutral endopeptidase 24.11/CD10 on neutrophils in a model of endotoxaemia in vitro. Lipopolysaccharide added to human whole-blood induced a marked and sustained CD10/neutral endopeptidase upregulation that was already detectable at 0.1 ng/ml and was maximal at a lipopolysaccharide concentration of 10 ng/ml.
2. We observed that neither tumour necrosis factor-α nor any newly synthesized protein was involved in the upregulation observed after 1 h incubation with 10 ng/ml lipopolysaccharide.
3. We further studied whether the lipopolysaccharide-induced CD10/neutral endopeptidase upregulation was mediated by lipopolysaccharide binding to the neutrophil CD14 receptor. Incubation of whole blood with an anti-CD14 monoclonal antibody before the addition of 0.1 ng/ml or 0.5 ng/ml lipopolysaccharide resulted in complete inhibition of CD10/neutral endopeptidase upregulation. In contrast, at a lipopolysaccharide concentration of 10 ng/ml, the anti-CD14 monoclonal antibody had an incomplete blocking effect.
4. The differential requirement for the CD14 receptor, depending on the lipopolysaccharide dose, was confirmed by the study of a patient suffering from paroxysmal nocturnal haemoglobinuria (in whom a complete defect in neutrophil CD14 expression was previously documented).
5. We finally confirmed these results using purified neutrophils, demonstrating that lipopolysaccharide-induced CD10/neutral endopeptidase upregulation depends on direct interaction with neutrophil CD14.
Compartmental Analysis of Colonic Transit Reveals Abnormalities in Constipated Patients with Normal Transit
Authors: Bouchoucha Michel , Devroede Ghislain , Renard Phillipe , Arhan Pierre , Barbier Jean-Phillipe , Cugnenc Paul-Henri 
Published: August 2015

1. The aims of this study were to investigate if compartmental analysis can be used to analyse colonic transit measurements and to search for a relationship between transit time and the parameters deduced from this analysis. In addition, an attempt was made to determine if such analysis could reveal a functional abnormality in patients who complain of constipation but have normal colonic transit.
2. The subjects included 11 healthy controls, 10 patients with chronic diarrhoea and 55 constipated patients. Segmental and total colonic transit time were measured using a previously described method. Compartmental analysis was based on a three-compartment system, with k1, k2 and k3 being the coefficients of diffusion out of the right colon, the left colon and the rectosigmoid area respectively.
3. Patients complaining of constipation who had delayed transit time were the only subjects to have lower values of coefficient k1 than controls. k2 was lower than normal in all patients complaining of constipation, but this decrease was more marked in subjects with delayed colonic transit time than in subjects with normal colonic transit time. All patients complaining of constipation had lower values of k3 than control subjects.
4. This study shows that analysis of colonic transit time is feasible using a simple diffusion law, and that the results are correlated to clinical data. Moreover, this analysis permits detection of abnormalities in two groups of subjects: those who complain of constipation but are labelled as having normal colonic transit time and those who have chronic diarrhoea.
Regional Sympathetic Nervous Activation after a Large Meal in Humans
Authors: Cox Helen S. , Kaye David M. , Thompson Jane M. , Turner Andrea G. , Jennings Garry L. , Itsiopoulos Catherine , Esler Murray D. 
Published: August 2015

1. To investigate the link between post-prandial thermogenesis and sympathetic nervous activation we have studied the effects of a single large meal on regional sympathetic nervous activity in healthy, lean subjects.
2. In nine male subjects, noradrenaline spillover was measured from the heart, kidney and liver using isotope dilution, both while fasting and after consumption of a high-energy liquid meal of composition 53% carbohydrate, 32% fat and 15% protein (energy value 2.64–3.51 MJ). Regional oxygen consumption, whole-body oxygen consumption and, in a subset of subjects, muscle sympathetic nerve firing (microneurography) were also measured.
3. Both whole-body oxygen consumption (P &lt; 0.03) and total body spillover of noradrenaline (P &lt; 0.01) rose after the meal, with peak increases of 24% and 56% respectively. Spillover of noradrenaline from the heart was unchanged, that from the hepatosplanchnic circulation increased marginally (0.377 nmol/min to 0.480 nmol/min, P = 0.09), while renal noradrenaline spillover more than doubled (0.440 nmol/min to 0.937 nmol/min, P &lt; 0.05). Skeletal muscle sympathetic nerve activity (peroneal nerve) increased from 7.7 bursts/min at rest to peak at 17.9 bursts/min 60 min after the meal in the three subjects in whom stable recordings were obtained.
4. The meal increased oxygen consumption in the kidneys and liver significantly, from 11.5 ± 1.6 ml/min to 14.5 ± 1.1 ml/min and from 46 ± 7 ml/min to 57 ± 6 ml/min respectively (P &lt; 0.05), but not in the heart.
5. Consumption of a large meal produces a substantial and relatively selective increase in sympathetic outflow to the kidneys and skeletal muscle. While resting regional oxygen consumptions and noradrenaline spillovers were related, the changes that occurred in each were unrelated, so that no direct relationship could be demonstrated between post-prandial thermogenesis and sympathetic activity.
t(8;21) Breakpoints are Clustered between Alternatively Spliced Exons of MTG8
Authors: Tighe Jane E. , Calabi Franco 
Published: August 2015

1. The (8;21) translocation, which is consistently associated with a subgroup of acute myeloid leukaemia, involves two loci: runt on chromosome 21 and MTG8 on chromosome 8.
2. Breakpoints in runt fall within a single intron that is located immediately downstream of a phylogenetically conserved DNA-binding domain (the ‘runt box’).
3. We now show that most breakpoints on chromosome 8 fall within a region between two alternative 5′ MTG8 exons. Thus, we predict that chimaeric genes on both the derivative(8) and the derivative(21) chromosomes have the potential to be transcriptionally active.
Cutaneous Vasoconstrictor Response Induced by Inspiratory Gasp in Relation to Sex and Age
Authors: Lau Ying-Tung , Liu Chi-Feng , Tsai C. C. 
Published: August 2015

1. Vasoconstrictor responses to inspiratory gasp were determined in fingertip skin by laser Doppler flowmetry in relation to age and gender of healthy adults. Variations of the responses were examined together with variations in body mass index and vital capacity.
2. In the absence of any significant difference in the baseline blood flow, the index of vasoconstrictor response (per cent change) induced by inspiratory gasp was higher in young males than in young females (71.4% versus 59.4%; P&lt;0.05), and in the same direction as the change in vital capacity determined in the same laboratory setting. Similar parallel differences in the indexes of vasoconstrictor response and vital capacity existed between young and middle-aged males, suggesting that the differences observed were not due to gender or age per se.
3. Strong positive correlations between the index of the vasoconstrictor response and vital capacity in the same subject were found when young males and females were pooled together and when young and middle-aged males were pooled together. Furthermore, after graded inspiratory gasp, graded vasoconstrictor response was observed in the same subject, indicating a close relationship between the depth of inspiration (magnitude of stimulus) and the index of the vasoconstrictor response (reactivity).
4. We concluded that the index of the vasoconstrictor response induced by inspiratory gasp depends significantly on the magnitude of the vital capacity. These results provide a new approach for quantifying dynamic changes in skin blood flow and raise caveats about comparing differences in neurovascular functions using single measurements of vasoconstrictor response induced by inspiratory gasp as an index.
Contribution of Age and Intimal Lesion Morphology to Coronary Artery Wall Mechanics in Coronary Artery Disease
Authors: Kok Wouter E. M. , Peters Ron J. G. , Prins Martin H. , Piek Jan J. , Koch Karel T. , David George K. , Visser Cees A. 
Published: August 2015

1. Atherosclerotic changes of the coronary vascular wall include localized plaque formation and diffuse hardening, both of which influence tensile strength of the inner vascular wall. Insight into the relation between age, the atherosclerotic process and vessel wall elasticity may contribute to the prevention of secondary vascular wall damage.
2. To evaluate the determinants of coronary artery wall elasticity, we studied a group of 34 patients, aged 54.6 ± 10.1 years, who underwent balloon angioplasty for coronary artery disease. With the use of 30 MHz intravascular ultrasound, a total of 127 cross-sections of coronary artery segments outside the balloon area were studied. The echographic appearance of the intima was classified as normal intimal thickening, fibrous lesions and calcified lesions. Fibrofatty lesions, which are believed to be rupture prone, were analysed separately. From the lumen area change, measured by semiautomated planimetry from digitized ultrasound images, and simultaneously measured aortic pressure change during the diastolic phase of the cardiac cycle, two elastic parameters were derived, pressure—strain modulus Ep and β-stiffness.
3. In univariate analysis Ep and β-stiffness were determined by age, vessel size, intimal composition, severity of lumen obstruction and gender, but not by eccentricity of the lesion or a specific coronary artery. In multivariate linear analysis, increased vessel wall stiffness was independently determined by advanced age, larger vessel size, intimal composition, and to a lesser extent by female gender. Elastic parameters of fibrofatty lesions were not different from other fibrous lesions.
4. Coronary artery wall elasticity is independently determined by age, vessel size and intimal composition.
Effect of Water Restriction during Adaptation to a Low-Sodium Diet in Man
Authors: Sutters M. , Peart W. S. 
Published: August 2015

1. Plasma sodium concentration may influence renal sodium excretion. We have examined the possibility that the fall in plasma sodium that occurs during salt restriction in man might be an important stimulus for renal sodium conservation.
2. In order to prevent the fall in plasma sodium that usually occurs during dietary salt restriction, we water restricted (200 ml/day) six normal subjects for the 2 days after the transition from 260 (high-sodium diet, day 3) to 20 mmol (low-sodium diet, days 4 and 5) sodium per day. In the control (hydrated) group water intake was held constant at 1800 ml/day.
3. Plasma sodium fell during the low-sodium diet in the hydrated group but remained constant in the dehydrated group (141.3 ± 0.2 to 140.2 ± 0.2 mmol/l versus 141.1 ± 0.3 to 141.3 ± 0.3 mmol/l). Plasma arginine vasopressin concentration was significantly higher and urine flow lower during the low-sodium diet in the dehydrated group (arginine vasopressin on day 5: hydrated group, 0.72 ± 0.1 pmol/l; dehydrated group, 2.18 ± 0.5 pmol/l). Weight fell by a similar amount in both groups (hydrated group, 1.23 ± 0.17 kg; dehydrated group, 1.45 ± 0.19 kg).
4. On the low-sodium diet there were no differences between groups in changes in plasma renin activity (hydrated group, 1.6 ± 0.24 to 4.78 ± 0.65 nmol angiotensin I h−1 ml−1; dehydrated group 1.57 ± 0.18 to 5.14 ± 0.56 nmol angiotensin I h−1 ml−1) or atrial natriuretic peptide (hydrated group, 23 ± 2.3 to 14.7 ± 1.6 pg/ml; dehydrated group, 26.8 ± 3.6 to 12.7 ± 1.3 pg/ml). Salivary aldosterone concentration increased further in the dehydrated study, but only on day 5.
5. Sodium excretion fell further in the dehydrated group over the first 16 h of the low-sodium diet on day 4 (hydrated group, 8.62 ± 0.76 mmol/h; dehydrated group, 6.57 ± 0.38 mmol/h). Creatinine clearance fell on day 5 (low sodium) in the dehydrated group but did not change significantly in the hydrated group (hydrated group, 152 ± 7 to 137 ± 7; dehydrated group, 157 ± 7 to 123 ± 7 ml/min).
6. We conclude that the fall in plasma sodium during salt restriction is not an important trigger for renal sodium conservation in man. The principal difference between studies was the elevation of arginine vasopressin in the dehydrated study. Differences in salivary aldosterone concentration occurred on day 5 only, too late to account for the differences in sodium excretion on day 4. Under the conditions of this study, our findings could be explained if physiological range elevation of arginine vasopressin has an antinatriuretic effect.
Postprandial Sympatho-Adrenal Activity: Its Relation to Metabolic and Cardiovascular Events and to Changes in Meal Frequency
Authors: Vaz Mario , Turner Andrea , Kingwell Bronwyn , Chin Jaye , Koff Elizabeth , Cox Helen , Jennings Garry , Esler Murray 
Published: August 2015

1. Sympatho-adrenal activity was measured after the consumption of a 3.15 MJ mixed meal. Whole-body noradrenaline spillover rates, forearm plasma noradrenaline spillover and adrenaline secretion rates were derived using isotope dilution methodology. Heart rate and blood pressure spectral analysis measurements were also made. The relation of sympatho-adrenal activity to thermogenic and cardiovascular events was studied. Sympathetic nervous and thermogenic responses were measured for 120 min after the single 3.15 MJ meal and compared with those after three 1.05 MJ meals, given 30 min apart.
2. Whole-body and forearm plasma noradrenaline spillover, and the 0.1 Hz component of systolic pressure power all increased significantly postprandially, while the 0.1 Hz component of heart rate variability, an indirect index of cardiac sympathetic nervous activity, remained unaltered. Adrenaline secretion was unaltered postprandially. Whole-body plasma noradrenaline spillover and thermogenesis during the 120 min postprandial period were 37% and 36% higher after the single meal as compared with the multiple meals, although this was not statistically significant.
3. The sympathetic neural responses were delayed in relation to peak plasma insulin levels and sustained in the face of declining insulin levels. Energy expenditure increased significantly postprandially, but there was no direct quantitative relationship to plasma noradrenaline spillover. Forearm oxygen consumption did not increase postprandially despite significant increases in regional noradrenaline spillover. Thus, no close relation was demonstrated between postprandial sympathetic nervous activation and either insulin secretion or thermogenesis.