bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Flow Cytometric Method to Measure Shape Change of Human Neutrophils
Authors: Cole A. T. , Garlick N. M. , Galvin A. M. , Hawkey C.J. , Robins R. A. 
Published: August 2015

1. We report a flow cytometric method in which changes in forward angle light scatter are shown to correlate with microscopically evaluated shape change in stimulated human neutrophils. Neutrophil movement and chemotaxis is conventionally measured using Boyden chambers, which is a laborious and exacting technique. Microscopic scoring of neutrophil shape change has been shown to correlate well with Boyden chamber measurements, and although less laborious, still requires manual counting.
2. We now show that measurement of forward angle light scatter in a benchtop flow cytometer correlates closely with microscopic evaluation of neutrophil shape change in dose—response stimulation experiments with leukotriene B4, N-formyl-methionine-leucine-phenylalanine or interleukin-8. The relationship between shape change and increased forward angle light scatter was confirmed using the fluorescence-activated cell sorter to separate partially stimulated neutrophils, followed by reanalysis by flow cytometry and microscopic examination.
3. This flow cytometric method provides a convenient, rapid and objective measure of neutrophil responses to external stimuli.
Increased Inward Passive Permeability in Vitro to Sodium in Uraemic Erythrocytes
Authors: Corry Dalila B. , Ellis Charma C. , Tuck Michael L. 
Published: August 2015

1. We have reported a normal sodium (Na) pump, but decreased loop-diuretic-sensitive Na efflux in erythrocytes from patients with chronic renal failure on haemodialysis, suggesting a different mode of co-transport in uraemia.
2. The present work extends these findings and examines in vitro simultaneous unidirectional and radiolabelled Na and K fluxes through the Na/K/Cl co-transport and the Na/K pump in washed erythrocytes from seven subjects with chronic renal failure and seven controls. Erythrocyte cytosolic calcium was also examined.
3. Ouabain-sensitive 86Rb influx was similar in patients and controls (1.76 ± 0.19 versus 1.72 ± 0.13 mmol h−1 litre−1 of erythrocytes) as was ouabain-sensitive 22Na efflux (3.62 ± 0.36 versus 4.04 ± 0.39 mmol h−1 litre−1 of erythrocytes).
4. Bumetanide-sensitive 86Rb and 22Na influx and 22Na efflux were measured at three concentrations (4, 8 and 12 mmol/l) of external K. In chronic renal failure, mean bumetanide-sensitive 22Na efflux was decreased at all external K concentrations compared with controls, and at physiological concentrations (4 mmol/l) external K was lower than controls (0.14 ± 0.01 versus 0.38 ± 0.05 mmol h−1 litre−1 of erythrocytes, P &lt; 0.01). Mean bumetanide-sensitive 86Rb influx was also reduced in chronic renal failure at all external K concentrations, and at 4 mmol/l external K was lower than controls (0.13 ± 0.04 versus 0.34 ± 0.04 mmol h−1 litre−1 of erythrocytes, P &lt; 0.01). Conversely, bumetanide-sensitive 22Na influx was markedly increased at all external K levels in chronic renal failure, and at 4 mmol/l external K values were elevated compared with controls (0.64 ± 0.18 versus 0.34 ± 0.04 mmol h−1 litre−1 of erythrocytes, P &lt; 0.001). The mean cytosolic calcium concentration was higher in erythrocytes in chronic renal failure than controls (134.4 ± 8.6 versus 63.7 ± 5.8 nmol/l, P &lt; 0.001).
5. Thus, in washed erythrocytes incubated in artificial media there is a markedly increased ouabain-insensitive Na influx in subjects with chronic renal failure which might be explained in part by the higher levels of cytosolic calcium. In vivo, this cell defect combined with suppression of the Na/K pump could lead to intracellular Na accumulation and play a role in uraemic complications.
Low Concentrations of Ouabain Increase Cytosolic Free Calcium Concentration in Rat Vascular Smooth Muscle Cells
Authors: Zhu Zhiming , Tepel Martin , Neusser Marcus , Zidek Walter 
Published: August 2015

1. Low ouabain concentrations in the nanomolar range significantly increased cytosolic free calcium concentration.
2. The ouabain-induced cytosolic free calcium concentration increase was due to transplasmamembrane calcium influx, which could be prevented in the absence of extracellular calcium or by addition of the calcium channel blocker nifedipine.
3. The amount of stored cellular Ca2+, as determined by the thapsigargin-induced cytosolic free calcium concentration increase, was also enhanced by 1 nmol/l ouabain.
4. It is concluded that low ouabain concentrations affect intracellular cytosolic free calcium concentration homoeostasis.
Plasma Inhibitory Activity against Tumour Necrosis Factor in Fulminant Hepatic Failure
Authors: Keane Helen M. , Sheron Nick , Goka John , Hughes Robin D. , Williams Roger 
Published: August 2015

1. Soluble tumour necrosis factor receptors released into the circulation inhibit the effects of excess tumour necrosis factor-α and represent an important protective response.
2. In this study we have measured the levels of tumour necrosis factor and soluble tumour necrosis factor receptors p55 and p75 in the plasma of 10 patients with fulminant hepatic failure and 10 healthy control subjects. The capacity of the plasmas at varying dilutions to inhibit the biological activity of 1000 pg/ml of recombinant tumour necrosis factor in a tumour necrosis factor cytotoxicity assay in vitro was also determined.
3. The mean plasma levels of tumour necrosis factor in patients with fulminant hepatic failure (48.4 ± 10.9 pg/ml) were significantly increased compared with normal control subjects (6.1 ± 1.04 pg/ml, P &lt; 0.01). Plasma soluble tumour necrosis factor receptors p55 and p75 were also significantly elevated in patients with fulminant hepatic failure (18.16 ± 9.94 ng/ml and 16.06 ± 9.93 ng/ml respectively) when compared with normal control subjects (1.28 ± 0.24 ng/ml and 1.62 ± 0.91 ng/ml, P &lt; 0.001).
4. Fulminant hepatic failure plasma had a much lower capacity to inhibit tumour necrosis factor bioactivity in vitro, with a statistically significant difference between the inhibitory capacity of the fulminant hepatic failure and normal plasma seen at plasma dilutions of 1:5 and 1:20 (P &lt; 0.05).
5. The reduced tumour necrosis factor neutralization capacity observed in fulminant hepatic failure, despite the increased levels of soluble tumour necrosis factor receptors, suggests enhanced susceptibility to the potential deleterious effects of tumour necrosis factor in fulminant hepatic failure.
Thermoregulation and Heart Rate Variability
Authors: Fleisher Lee A. , Frank Steven M. , Sessler Daniel I. , Cheng Christi , Matsukawa Takashi , Vannier Carole A. 
Published: August 2015

1. Heart rate variability is modulated by multiple control systems, including autonomic and hormonal systems. Long-term variability, i.e. the very low-frequency band of the power spectra, has been postulated to reflect thermoregulatory vasomotor control, based upon thermal entrainment experiments. However, the relationship between thermoregulatory responses (vasoconstriction and shivering) and heart rate variability has not been studied.
2. We performed two distinct protocols in a series of human subjects. In the first protocol, core temperature was reduced by intravenous infusion of cold saline, while skin temperature was unchanged. The second protocol involved skin-surface warming and cooling until shivering developed. Power spectral analysis was performed using a fast Fourier transformation, and the area in three distinct band-widths was determined.
3. Very low-frequency power (0.0039–0.04 Hz) increased significantly in response to core cooling, peripheral vasoconstriction and shivering, while both very low- and low- (0.04–0.15 Hz) frequency power increased in response to skin-surface cooling. Heart rate decreased during core cooling-induced vasoconstriction, suggesting a direct thermal response, and increased in relation to the metabolic demands associated with shivering.
4. Our results suggest that very low-frequency power is modulated by thermal stimuli which result in core hypothermia and thermoregulatory activity, while skin-surface cooling without core hypothermia does not selectively modulate this frequency band.
Haemodynamic Effects of Eating: The Role of Meal Composition
Authors: Høst U. , Kelbaek H. , Rasmusen H. , Court-Payen M. , Christensen N. Juel , Pedersen-Bjergaard U. , Lorenzen T. 
Published: August 2015

1. The purpose of this study was to investigate the effect of fractional meal stimulation on postprandial haemodynamic changes, the possible correlation between these changes and the potential mediating role of circulating catecholamines and insulin.
2. Healthy young subjects were studied before and after ingestion of isocaloric, isovolumetric high-protein, carbohydrate or fat meals (80–85% of total energy), 60 kJ per kg of body weight. Multigated radionuclide cardiography with autologous 99mTc-labelled erythrocytes was performed for assessment of cardiac output, venous occlusion plethysmography to obtain forearm blood flow and Doppler-ultrasonography for portal vein flow. Plasma levels of catecholamines and insulin were determined by radioimmunoassay.
3. Cardiac output increased considerably after each meal, including the control meal (water) with only minor differences in extent and timing. Left ventricular volumes increased after food intake, most pronounced after carbohydrate and protein. Forearm blood flow increased only after carbohydrate and protein. Portal vein flow increased after all meals, especially after fat, but also after the control meal. There was a significant correlation between the increment in cardiac output and changes in forearm and portal vein flow, but no correlation between either haemodynamic response and plasma catecholamines or insulin.
4. Postprandial cardiovascular changes are not substantially different after various isocaloric and isovolumic meal compositions. Gastric distension seems to play a role in the increase in cardiac output, accomplished by ventricular dilatation. These changes seem to some extent to be linked to changes in muscle and splanchnic flow.
Differential Effects of Low- and High-Intensity Lower Body Negative Pressure on Noradrenaline and Adrenaline Kinetics in Humans
Authors: Jacobs Marie-Cecile , Goldstein David S. , Willemsen Jacques J. , Smits Paul , Thien Theo , Lenders Jacques W. M. 
Published: August 2015

1. Lower body negative pressure provides a means to examine neurocirculatory reflexive responses to decreases in venous return to the heart. We assessed whether the pattern of catecholaminergic responses to lower body negative pressure depends on the intensity of the stimulus (−15 versus −40 mmHg).
2. In 14 healthy subjects, responses of forearm blood flow and noradrenaline spillover and of total body noradrenaline and adrenaline spillover were assessed during infusion of [3H]noradrenaline and [3H]adrenaline during −15 and −40 mmHg of lower body negxative pressure.
3. During lower body negative pressure at −15 mmHg, heart rate and pulse pressure did not change, but forearm vascular resistance increased by 25–50%. Forearm noradrenaline spillover increased by about 50%, from 0.63 ± 0.16 to 0.94 ± 0.23 pmol min−1 100 ml−1 (P&lt;0.05). Total body noradrenaline spillover did not change, and total body adrenaline spillover increased significantly by about 30%. Clearances of noradrenaline and adrenaline were unchanged.
4. During lower body negative pressure at −40 mmHg, heart rate increased and pulse pressure decreased. Forearm vascular resistance increased by about 100%, and forearm noradrenaline spillover increased by 80%, from 0.73 ± 0.19 to 1.32 ± 0.36 pmol min−1 100 ml−1 (P&lt;0.05). Total body noradrenaline spillover increased by 30%, and total body adrenaline spillover increased by about 50%. Clearances of both noradrenaline and adrenaline decreased.
5. The results are consistent with the view that selective deactivation of cardiopulmonary baroreceptors during low-intensity lower body negative pressure increases sympathoneural traffic to forearm skeletal muscle and increases adrenomedullary secretion without a concomitant generalized increase in sympathoneural outflows. Concurrent deactivation of cardiopulmonary and arterial baroreceptors during high-intensity lower body negative pressure evokes a more generalized increase in sympathoneural activity, accompanied by further increased adrenomedullary secretion and decreased plasma clearances of noradrenaline and adrenaline. The findings support differential increases in skeletal sympathoneural and adrenomedullary outflows during orthostasis, with more generalized sympathoneural responses to systemic hypotension.
Nitric Oxide in Streptozotocin-Induced Diabetes Mellitus in Rats
Authors: Maree Abed , Peer Gari , Iaina Adrian , Blum Miriam , Wollman Yoram , Csernihovsky Tamara , Silverberg Donald S. , Cabili Shaltiel 
Published: August 2015

1. The present study was performed to determine the relationship between diabetic glomerular hyperfiltration and nitic oxide as modulated by the chronic administration of l-arginine and/or N-ω-nitro-l-arginine, a known nitric oxide synthase inhibitor in streptozotocin-induced diabetic rats.
2. Normal rats and rats drinking hypertonic glucose (10%) were used as time-controlled groups. Six weeks after administration of streptozotocin the diabetic rats had significantly higher creatinine clearance (667 ± 53 μl min−1 100 g−1 body weight) than before and streptozotocin (456 ± 38 μl min−1 100 g−1 body weight, P&lt;0.005) and very high plasma (37.8 ± 10.9 μmol/l) and urinary (3.492 ± 0.179 nmol min−1 100 g−1 body weight) nitrite + nitrate (stable metabolites of nitric oxide) values compared with before streptozotocin administration [19.3 ± 2.8 μmol/l (P&lt;0.001) and 0.420 ± 0.051 nmol min−1 100 g−1 body weight (P&lt;0.001) respectively]. The 6-week diabetic rats had higher systolic blood pressure (124.2 ± 2.9 mm Hg, P&lt;0.05) than before streptozotocin (108 ± 8 mmHg), but had a value similar to that of the hypertonic-glucose-drinking rats.
3. The diabetic rats supplemented with l-arginine did not show an increase in creatinine clearance and had a lower urinary excretion of nitrite + nitrate (0.999 ± 0.27 nmol min−1 100 g−1 body weight, P&lt;0.005) than the respective untreated streptozotocin-induced diabetic rats. Creatinine clearance increased in the normal and glucose-drinking rats that received l-arginine. The administration of l-arginine resulted in significant reduction in blood pressure in all groups studied. The chronic nitric oxide synthase inhibitor resulted in high blood pressure, and in a significant decrease in creatinine clearance and urinary nitrite + nitrate excretion in all groups studied. In both diabetic and glucose-drinking rats, the l-arginine therapy resulted in significantly lower plasma and urinary glucose levels than in their respective untreated control groups.
4. The nitric oxide synthase inhibitor increased the plasma and urinary glucose concentration in both diabetic and glucose-drinking rats.
5. Our results indicate that diabetic rats are characterized by high plasma concentrations and elevated urinary excretion of nitrite + nitrate, suggesting a state of high nitric oxide production. The vascular response to nitric oxide in diabetic rats may be different at the glomerular and peripheral vascular bed.
Fasting Increases the Extent of Muscle Necrosis in the mdx Mouse
Authors: Helliwell T. R. , MacLennan P. A. , McArdle A. , Edwards R. H. T. , Jackson M. J. 
Published: August 2015

1. The effects of fasting for 48 h were investigated in CS7BL/10 (wild type) and age-matched C57BL/10 dystrophin-deficient (mdx) mice.
2. Fasting resulted in an increased percentage of necrotic fibres in muscles from the hindlimb and lumbar regions of mdx mice. The percentage of necrotic fibres of forelimb and chest muscles of mdx mice was unaltered by fasting. In wild-type mice, very few necrotic fibres were observed after fasting.
3. The necrotic changes in fasted mdx muscle were not accompanied by altered energy status as evaluated by muscle ATP and phosphocreatine concentrations.
4. A significantly decreased rectal temperature was observed in mdx but not in wild-type mice after fasting.
5. Fasting would normally be expected to cause a reduction in muscle fibre size. The high prevalence of necrosis in fasted mdx mice is therefore an unusual response that may be related to disturbance of the mechanisms which, in the fed state, compensate for the dystrophin deficiency in these animals.
Effects of Facial Cooling on Elderly and Young Subjects: Interactions with Breath-Holding and Lower Body Negative Pressure
Authors: Collins K. J. , Abdel-Rahman T. A. , Easton J. C. , Sacco P. , Ison J. , Doré C. J. 
Published: August 2015

1. The effects of convective facial cooling by cold air on arterial blood pressure, heart rate and finger blood flow and on the reflex interactions between facial cooling and respiratory and orthostatic cardiac reflexes have been examined in 28 young adults (20–39 years) and 17 elderly (66–78 years) volunteer subjects.
2. During 2 min facial cooling alone, bradycardia was smaller (P &lt; 0.001) and reduction in finger blood flow smaller (P &lt; 0.001) in elderly subjects than in young subjects. Increases in systolic blood pressure and mean arterial pressure were similar and diastolic pressure increased only in the young subjects. Systolic blood pressure and mean arterial pressure remained elevated in the elderly 1 min after facial cooling, but subsided in the young.
3. Arterial blood pressure increased more during a 30-s breath-hold in expiration than in inspiration (P &lt; 0.001) in both groups, and this was exaggerated by breath-hold in expiration combined with facial cooling. The bradycardia produced by facial cooling and breath-holding in expiration was more pronounced in the young subjects than in the elderly (P &lt; 0.002).
4. Interactions between facial cooling and orthostatic reflexes induced by lower-body negative pressure showed significantly different age-related linear trends. Facial cooling diminished the hypotension induced by lower-body negative pressure in both groups. Facial cooling had a greater effect in diminishing the lower-body negative pressure-induced tachycardia in the young than in the elderly.
5. The mechanism of alteration of the facial cooling response in elderly subjects could be largely impairment of arterial baroreflexes, particularly as a result of reduced cardiac vagal activity as well as impairment of cardiopulmonary reflexes with ageing.
Smooth Muscle-Derived Nitric Oxide is Elevated in Isolated Forearm Veins in Human Alcoholic Cirrhosis
Authors: Ryan Jeremy , Jennings Garry , Dudley Frank , Chin-Dusting Jaye 
Published: August 2015

1. Cirrhosis is often complicated by disturbances in the systemic circulation. We have previously demonstrated decreased vascular responses to vasoconstrictors in forearm resistance arteries in subjects with alcoholic cirrhosis. In the current study we investigate the role of the potent endogenous vasodilator nitric oxide in the peripheral circulation of these patients.
2. Ten patients with alcoholic cirrhosis (Pugh grade A) and 10 age-matched control subjects were studied. The effect of blockade of nitric oxide synthesis was studied both in vivo in forearm resistance arteries using forearm venous occlusion plethysmography and in vitro in veins isolated from the forearm. The role of endothelium-derived nitric oxide was studied in vivo using the endothelium-dependent vasodilator acetylcholine.
3. Mean arterial pressure and forearm basal flow in vivo were similar in the two groups. The constrictor response (percentage decrease in forearm blood flow) to noradrenaline (100 ng/min) was 26% smaller in patients with cirrhosis (31.65 ± 2.64%) than in control subjects (42.75 ± 3.87%, P = 0.037). Constrictor responses to the nitric oxide synthase inhibitor NG-monomethyl-l-arginine were not different in the two groups. Dilator responses to acetylcholine were significantly attenuated in cirrhotic patients compared with control subjects.
4. To investigate the role of smooth muscle-derived nitric oxide in vitro, all veins were stripped of their endothelium. Responses to noradrenaline were significantly diminished in veins isolated from patients with cirrhosis compared with control subjects. Incubation with the nitric oxide synthase inhibitor Nω-nitro-l-arginine had no effect on responses to noradrenaline in veins from control subjects but significantly enhanced the maximal response to noradrenaline by 23.95% (range 3.77–100%, P = 0.043) in veins from patients with cirrhosis.
5. Responses to noradrenaline were attenuated in vivo in forearm resistance arteries in patients with alcoholic cirrhosis. This impairment was also apparent in forearm isolated veins, stripped of the endothelium. Our data exclude a major role for endothelium-derived nitric oxide but highlight a possible role for smooth muscle-derived nitric oxide.
Determination of Protein Synthesis in Lymphocytes in Vivo after Surgery
Authors: Essén Pia , McNurlan Margaret A. , Thorell Anders , Tjäder Inga , Caso Giuseppe , Anderson Susan E. , Wernerman Jan , Garlick Peter J. 
Published: August 2015

1. The stimulation and depression of peripheral blood lymphocytes has previously been studied in vitro, showing an immune depression postoperatively; however, it is difficult to interpret these in vitro findings. Therefore, an in vivo technique has been established for determination of the fractional protein synthesis rate, as an index of metabolic activity in human peripheral blood lymphocytes, by using a stable isotope technique.
2. The rate of protein synthesis was calculated from the increase in enrichment of l-[2H5]phenylalanine in protein of a mixed population of mononuclear leucocytes, isolated by density gradient, after an intravenous flooding dose of l-[2H5]phenylalanine. A linear time course of isotopic incorporation into the cells was demonstrated.
3. The fractional rate of protein synthesis of a mixed population of mononuclear leucocytes was studied in relation to surgical interventions and to potential modifiers of the response. The fractional synthesis rate increased 24 h after open and laparoscopic cholecystectomy (49 ± 19% and 40 ± 14% respectively, P &gt; 0.02), irrespective of postoperative total parenteral nutrition or preoperative glucose infusion. In contrast to surgery, insulin did not stimulate protein synthesis in peripheral mononuclear leucocytes.