bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Interaction of Cigarette Smoke Solution with α1-Antitrypsin: Effect on Inhibitory Capacity, Electrophoretic Mobility and Immunological Measurement
Authors: Stockley Robert A. , Afford Simon C. 
Published: August 2015

1. The effects of an aqueous solution of cigarette smoke upon the functional, immunological and electrophoretic assessment of α1-antitrypsin have been studied.
2. The addition of cigarette smoke reduced the inhibitory capacity of the α1-antitrypsin and this was associated with at least a 22% underestimation of the protein concentration by immunological measurement.
3. Furthermore the cigarette-smoke-damaged α1-antitrypsin had an increased electrophoretic mobility in plain agarose compared with the pure protein and was more susceptible to proteolytic damage by elastase.
4. Comparison with results obtained in vivo suggests that oxidative damage to α1-antitrypsin is not the only mechanism involved in the reduction of its inhibitory capacity in secretions, even in non-smokers.
The Role of Cardiopulmonary Sympathetic Afferents in Blood Volume Homoeostasis in the Non-Human Primate
Authors: Cornish Kurtis G. , Gilmore Joseph P. 
Published: August 2015

1. Four Macaca fascicularis monkeys were bilaterally sympathectomized by removing the thoracic sympathetic chain from the middle cervical ganglion to the T-6 sympathetic ganglion. This was done chronically, allowing adequate recovery time. While under light pentobarbital anaesthesia, the animals were then subjected to blood volume expansions with isotonic, isooncotic dextran or to head-out immersions. Seven immersions and seven volume expansions were carried out.
2. With immersion, there were significant increases in blood pressure, central venous pressure, urine flow, sodium excretion, potassium excretion, glomerular filtration rate, percentage of filtered sodium excreted and free water clearance. Although blood pressure and central venous pressure initially increased during the first immersion period, heart rate continued to increase with the immersion, while blood pressure and central venous pressure remained constant. Volume expansion caused an increase in central venous pressure, urine flow, sodium and potassium excretion, osmolar clearance, free water clearance, percentage of filtered sodium excreted and glomerular filtration rate.
3. Since these results with both the immersions and volume expansions were not qualitatively different from those observed in control animals, it is concluded that cardiopulmonary sympathetic afferents are not necessary for the renal response to head-out immersion or blood volume expansion in the non-human primate.
Dose-Dependent Effects of Meclofenamate on Peripheral Vasculature of Conscious Rabbits
Authors: Banks R. A. , Beilin L. J. , Soltys J. 
Published: August 2015

1. Changes in systemic haemodynamics and organ blood flow were measured in conscious rabbits after various doses of intravenous sodium meclofenamate, an inhibitor of prostaglandin cyclo-oxygenase.
2. Meclofenamate had no effect on arterial pressure or cardiac output but caused a dose-dependent fall in renal blood flow.
3. Meclofenamate also reduced adrenal perfusion but, in contrast, caused a dose-dependent increase in blood flow to the brain, bronchial and hepatic circulation and to the testis. No effect was demonstrated on other organs studied.
4. The effect on the cerebral circulation was observed at the lowest dose of meclofenamate (0.75 mg/kg). Higher total doses were necessary for an effect on the renal and bronchial (3 mg/kg) and testicular and hepatic arteries (6 mg/kg).
5. The results suggest a variety of local vasomotor influences of renal and non-renal prostaglandins in conscious rabbits.
Development of the Respiratory Compensation to Progressive Metabolic Alkalosis Resulting from Potassium Depletion in Conscious Rats
Authors: Girard Pierre , Brun-Pascaud Monique , Pocidalo Jean-Jacques 
Published: August 2015

1. 288 arterial blood samples were obtained at successive times, through indwelling catheters, from conscious rats subjected to selective dietary potassium restriction for up to 5 weeks.
2. in control rats with unrestricted access to potassium [HCO−3]a = 25.4 mmol/l, pHa = 7.47, Paco2 = 34 mmHg, Pao2 = 94 mmHg and [K+]a = 4.3 mmol/l were steady and within the range of values reported in conscious rats. Five weeks of isolated potassium restriction resulted in significant hypokalaemia ([K+]a = 2.15 mmol/l) and metabolic alkalosis ([HCO−3]a = 34.1 mmol/l, pH 7.57). This alkalosis, due mostly to H+ transfer into cells, was accompanied by a significant increase in Paco2 to 36.4 mmHg and decrease in Pao2 to 88 mmHg, contrary to previous reports in man and dog. The administration of neutral sodium phosphate in addition to potassium restriction enhanced both the alkalosis ([HCO−3]a = 42.3 mmol/l, pH 7.61) and its respiratory compensation (Paco2 = 40.8, Pao2 = 82 mmHg), without altering the Paco2: [HCO−3]a relationship.
3. The opposite variations of Paco2 and Pao2 were significantly correlated to the increase in plasma bicarbonate concentration and described best by crossed sigmoid curves. The equations of both curves were calculated; their point of inflection occurred at the same bicarbonate concentration (36 mmol/l). The maximum intensity of respiratory compensation (0.62 mmHg Paco2 for each mmol [HCO−3]a/l) observed at this point fell within the range of values yielded by previous estimations.
Do Elderly Patients with An Excessive Fall in Blood Pressure on Standing Have Evidence of Autonomic Failure?
Authors: Robinson Brian J. , Johnson Ralph H. , Lambie David G. , Palmer Karen T. 
Published: August 2015

1. Blood pressure, heart rate and plasma catecholamine responses were examined in two groups of elderly subjects distinguished by blood pressure responses to standing. Subjects in the control group showed a fall of less than 15 mmHg in systolic blood pressure on standing; subjects in the orthostatic hypotension group had falls of more than 20 mmHg systolic and 10 mmHg diastolic blood pressure on standing.
2. The heart pressure response on standing showed no significant difference between the two groups.
3. The orthostatic hypotension patients had lower plasma noradrenaline concentrations than the control patients (P &lt; 0.01) in the supine position, but during 10 min standing there was no significant difference in noradrenaline levels between the groups, and the percentage increase of noradrenaline levels in the orthostatic hypotension group was greater (P &lt; 0.05) than in the control group.
4. in the supine position, diastolic blood pressure was higher (P &lt; 0.05) in the orthostatic hypotension group than in the control group.
5. We conclude that impairment of baroreceptor function is not involved in most cases of orthostatic hypotension in the elderly, nor is there reduction of sympathetic nervous activity. We suggest that mechanical changes or adrenoreceptor dysfunction are more likely to be important factors in orthostatic hypotension in the elderly.
Sex-Steroid Enzymes, Aromatase and 5α-Reductase in the Pancreas: A Comparison of Normal Adult, Foetal and Malignant Tissue
Authors: Iqbal M. Jawed , Greenway Brian , Wilkinson M. L. , Johnson P. J. , Williams Roger 
Published: August 2015

1. Following the finding of high levels of oestrogen receptor proteins in pancreatic carcinoma tissue, two enzymes involved in sex-steroid biosynthetic pathways, aromatase and 5α-reductase, have been measured.
2. Activities of aromatase, which converts testosterone into oestradiol, comparable with those found in pre-menopausal uterus (P &lt; 0.5) were found in all seven samples of pancreatic carcinoma tissue, and in a pooled sample of foetal pancreas. Measurable but significantly lower activities (P &lt; 0.001) of aromatase were found in seven specimens of normal pancreas.
3. 5α-Reductase activity, which converts testosterone into the more potent androgen 5α-dihydrotestosterone, was found in malignant pancreatic tissue at approximately half the level found in prostatic tissue (P &lt; 0.01) and at almost twice the levels found in either normal adult or pooled foetal pancreatic tissue (P &lt; 0.01).
4. These findings suggest that sex steroids are involved in foetal and adult pancreatic physiology.
5. Since these enzyme pathways are present in pancreatic carcinoma at greater levels than those in normal adult pancreas, it is possible that agents known to interfere with steroid metabolism could be of value in the treatment of this tumour.
Effects of Hydralazine versus Propranolol on Blood Velocity Patterns in Patients with Carotid Stenosis
Authors: Spence J. David 
Published: August 2015

1. Since endothelial damage due to flow disturbances is of postulated significance in the pathogenesis of atherosclerosis, this study examined the effects of antihypertensive drugs on carotid flow patterns in patients with known carotid stenosis. A Doppler Echoflow unit was used to display arterial velocities in red (normal range), yellow (increased velocity) and blue (abnormally increased velocity thought to represent turbulence and other departures from laminar flow).
2. Twenty patients were studied before drug, then during intravenous administration of hydralazine, 6–12 mg, and propranolol, 2–5 mg, over 10–15 min each, with return to baseline between drugs.
3. After hydralazine, the occurrence of abnormal high velocity flow patterns increased in 17 of 20 patients; there was no change in three patients. Propranolol reduced the occurrence of abnormal high velocity flow patterns in 19 of 20 patients (P &lt; 0.00001; chi-square).
4. These effects of antihypertensive drugs on arterial velocity patterns may be important in the selection of antihypertensive drugs to prevent or minimize the progression of atherosclerosis.
Increased Folate Catabolism in Mice with Ascitic Tumours
Authors: Kelly D. A. , Scott J. M. , Weir D. G. 
Published: August 2015

1. Folate deficiency is reported in association with certain malignant tumours, and it has been suggested that this arises from increased folate turnover and catabolism in such circumstances.
2. Using an experimental animal model to determine the rate of catabolism of [3H]pteroylglutamate (folic acid) by the quantitative estimation of the two urinary catabolites p-[3H]aminobenzoylglutamate and [3H]acetamidobenzoylglutamate, we have measured the rate of folate catabolism in mice with ascitic tumours.
3. There was a significant increase in the rate of catabolism in the mice with tumours compared with controls over a 10 day period. This was associated with the accumulation of ascitic fluid and an increase in the number of tumour cells in the treated animals.
4. The increase in catabolism appeared to be due to increased cell turnover of the tumour rather than an increase in cell mass, as the increase in mass of the tumour was negligible.
Patterns of Smoking: Measurement and Variability in Asymptomatic Smokers
Authors: Adams L. , Lee C. , Rawbone R. , Guz A. 
Published: August 2015

1. Measurements of patterns of puffing (cigarette-holder pneumotachograph) and ventilation (plethysmography) were made in ten asymptomatic smokers during the smoking of a cigarette, on four separate occasions.
2. There were marked individual differences and these were consistent over 3–5 weeks. In itself, the pattern of smoking could be responsible for a threefold variation in smoke intake.
3. Puffing but not inhalation became less intense as a cigarette was smoked.
4. It was not possible to predict indices of absorption from smoking patterns.
5. Certain smoking patterns, e.g. small puff volume, low puff frequency, short duration of inhalation and expulsion of volume between puff and inhalation, may be less harmful than others and this may explain why some individuals remain healthy despite a lifetime of smoking.
Calcium Metabolism Evaluated by 47Ca kinetics: Estimation of Dermal Calcium Loss
Authors: Charles P. , Jensen F. Taagehøj , Mosekilde L. , Hansen H. Hvid 
Published: August 2015

1. Seventy-seven calcium balance and 47Ca turnover studies were performed in normal volunteers (n = 15) and in patients with osteoporosis (n = 12), primary hyperparathyroidism (n = 8), osteogenesis imperfecta (n = 5), medullary carcinoma of the thyroid (n = 4), thyrotoxicosis (n = 2) and intestinal bypass for obesity (n = 11).
2. After intravenous injection of 20 μCi of 47Ca two retention curves of 47Ca were obtained: R1(t) directly measured on a whole-body counter and R2(t) calculated from the cumulated daily excretions of 47Ca in urine and faeces. The data were fitted to a modification of the continuously expanding exchangeable calcium pool model.
3. Dermal calcium loss was estimated from the serum 47Ca specific radioactivity curve and the constantly increasing difference between the two retention curves. The median dermal calcium loss in 77 studies was 1.50 mmol 24 h−1 1.73 m−2 (range 0.13-4.60).
4. The dermal calcium loss might be overestimated by redistribution of tracer or by eventual insufficient collection of urine and faeces. The possible influences of these errors have been evaluated.
5. Patients with primary hyperparathyroidism had a greater (P &lt; 0.02) dermal calcium loss (2.64 mmol; range 0.80–4.50) than a control group (1.38 mmol; range 1.25–2.34).
Dissociation between Calcium and Phosphate Absorption in Nephrotic Syndrome
Authors: Farrington K. , Newman S. P. , Varghese Z. , Moorhead J. F. 
Published: August 2015

1. Intestinal calcium and phosphate absorption have been measured in nine patients with nephrotic syndrome and normal renal function, by a combined radioisotope technique which allows simultaneous measurement of both quantities. The values obtained were compared with those obtained in 20 normal controls.
2. Calcium absorption in the nephrotic group was significantly lower than in the control group (P &lt; 0.01), but phosphate absorption in the nephrotic group did not differ from controls.
3. This dissociation between calcium and phosphate absorption provides further evidence for independent mechanisms governing the two absorption processes.
Biochemical Analysis of Hepatic Lipid in Alcoholic and Diabetic and Control Subjects
Authors: Cairns S. R. , Peters T. J. 
Published: August 2015

1. Percutaneous needle biopsy specimens of liver were obtained from alcoholic, diabetic and control patients. Micro-methods of lipid separation and quantification were employed to determine the detailed nature of hepatic lipid.
2. Triglyceride is the major accumulating liver lipid in both alcoholic and diabetic patients. Cholesteryl ester levels were raised in both alcoholic and diabetic patients but only diabetic patients had significantly increased free cholesterol and phospholipid levels. Determination of phospholipid/free cholesterol ratios revealed a significant decrease in alcoholic cirrhosis compared with controls.
3. Fatty acid ester analysis of hepatic phospholipid and triglyceride revealed significant differences between alcoholic patients and controls but not between diabetic patients and controls. An increased ratio of non-essential/essential fatty acids was found in the patients with alcoholic liver disease whereas those of diabetic patients were similar to the controls.
Responses of the Systemic Circulation and of the Renin—Angiotensin—Aldosterone System to Ketanserin at Rest and Exercise in Normal Man
Authors: Fagard Robert , Cattaert Anne , Lijnen Paul , Staessen Jan , Vanhees Luc , Moerman Emmanuel , Amery Antoon 
Published: August 2015

1. The systemic circulation at rest and during exercise was studied in ten normal male volunteers, after placebo on one occasion and after acute intravenous administration of the serotonergic antagonist ketanserin on another occasion. The effects of ketanserin on the components of the renin—angiotensin—aldosterone system, on plasma catecholamines and on exercise capacity for graded uninterrupted exercise were also investigated.
2. At rest in recumbency rapid intravenous injection of 10 mg of ketanserin, followed by a continuous infusion of 2 mg/h, produced an acute but transient fall in mean intra-arterial pressure of 6 mmHg compared with placebo. After 15 min the mean arterial pressure with ketanserin was within 2 mmHg of the mean pressure with placebo. In the sitting position both at rest and up to 30% of maximal work rate, the mean arterial pressure during ketanserin did not differ from the pressure on placebo. However, at higher levels of physical activity the rise in mean arterial pressure was lower with ketanserin; the pressure achieved with placebo was 7.5 mmHg higher at maximal work rate. Heart rate and cardiac output were significantly higher during ketanserin.
3. When the subjects were lying down and resting, plasma noradrenaline and adrenaline levels, plasma renin activity and angiotensin II concentration were not affected by ketanserin; however, these values were higher in the sitting position both at rest and during exercise. Plasma aldosterone was reduced by ketanserin during exercise and also when the subject was resting in the recumbent position.
4. Exercise capacity as measured by peak oxygen uptake was similar during ketanserin (3.09 ± se 0.12 litres/min) and during placebo (3.11 ± 0.13).
5. The data suggest that 5-hydroxytryptamine can have only a small role, if any, in pressure homoeostasis in sodium replete man at rest in recumbency. At moderate and heavy levels of exercise, the results are compatible with a role for 5-hydroxytryptamine in pressure regulation. Activation of the sympathetic nervous system by ketanserin is suggested by increases of plasma catecholamines, heart rate, cardiac output and plasma renin. The suppression of plasma aldosterone suggests that 5-hydroxytryptamine may have a role in the regulation of aldosterone secretion which is independent of angiotensin II.
The Effect of Leucocyte Elastase on the Immunoelectrophoretic Behaviour of α1-Antitrypsin
Authors: Stockley R. A. , Afford S. C. 
Published: August 2015

1. Two-dimensional immunoelectrophoresis and conventional sodium dodecyl sulphate-polyacryl-amide gel electrophoresis was performed on various mixtures of purified α1-antitrypsin (α1AT) and leucocyte elastase (LE).
2. The results confirm that α1AT inhibits LE by the formation of enzyme-inhibitor complexes demonstrable by both techniques.
3. The complexes break down with time and are not affected by pH in the presence of excess α1AT. However, the breakdown is more rapid in the presence of excess enzyme only at pH values where LE remains active. The resultant products of the complex breakdown include inactivated LE and α1AT that has undergone limited proteolysis.
4. It is concluded that the presence or absence of α1AT-enzyme complexes as demonstrated by two-dimensional immunoelectrophoresis must be interpreted with caution when studying α1AT function in lung secretions. The absence of such complexes does not mean that previous interaction with enzyme has not occurred, thereby accounting for a reduction in α1AT inhibitory capacity.
Experimental Mouse Muscle Damage: The Importance of External Calcium
Authors: Jones D. A. , Jackson M. J. , McPhail G. , Edwards R. H. T. 
Published: August 2015

1. The involvement of extracellular calcium in experimental muscle damage has been studied in an isolated mouse soleus muscle preparation.
2. The enzyme efflux and ultrastructural damage seen after excessive contractile activity were markedly reduced when the extracellular calcium was withdrawn. Low extracellular calcium also protected against the large enzyme efflux seen after treatment with low concentrations of detergent.
3. Treatment of the muscle with the calcium ionophore A 23187 caused significant release of enzyme from the muscle.
4. Nifedipine did not prevent the enzyme release after stimulation and although in some circumstances verapamil appeared to have some protective effect this was probably due to a local anaesthetic action on the muscle and not to any specific effect on calcium movement.
5. It is concluded that extracellular calcium is important in mediating at least the two forms of muscle damage studied here.
The Effect of Prostaglandin E2 Upon the Biochemical Response to Infused Angiotensin II in Human Pregnancy
Authors: Pipkin F. Broughton , Hunter J. C. , Turner S. R. , O'Brien P. M. S. 
Published: August 2015

1. The effects of angiotensin II infusion without and with simultaneous infusion of prostaglandin E2 were studied in 25 women in second trimester pregnancy. Twenty received one infusion of angiotensin II alone, followed by its infusion simultaneously with prostaglandin E2; five received two identical infusions of angiotensin II alone as controls.
2. Angiotensin II infusion alone was associated with suppression of plasma renin concentration to levels inversely proportional to the evoked change in diastolic blood pressure. Plasma renin substrate concentration was unchanged, but plasma aldosterone concentration rose markedly. This rise was inversely proportional to the threshold for pressor effect of angiotensin II.
3. Prostaglandin E2 administration alone was associated with increased plasma renin concentrations.
4. The pressor effect of angiotensin II was blunted when given together with prostaglandin E2 and plasma concentrations of angiotensin II reached were lower.
5. Plasma renin concentration was again suppressed during the joint infusion regimen; the degree of suppression was inversely proportional to the change in diastolic pressure. Plasma aldosterone concentration rose, but did not differ in the control and experimental groups.
6. Thus although the renin-angiotensin system is stimulated in normal pregnancy, the normal control mechanisms are still functional, and the capacity for further increases in activity exists.
Urinary 6-Ketoprostaglandin F1α in Genetically Hypertensive Rats of the Lyon Strain
Authors: Benzoni D. , Vincent M. , Sassard J. 
Published: August 2015

1. In order to assess the pathophysiological role of renal prostacyclin in genetic hypertension, the urinary excretion of its main stable metabolite, 6-ketoprostaglandin F1α, was followed in 12 hypertensive, normotensive and low blood pressure female rats of the Lyon strains at the ages of 5,9, 21, 32 and 45 weeks.
2. The urinary excretion of 6-ketoprostaglandin F1α, which progressively decreased in the three strains between 5 and 21 weeks of age, was found to be increased in 5- and 9-week-old hypertensive rats and it was reduced in 5-week-old low blood pressure rats, compared with age-matched normotensive controls.
3. The urinary 6-ketoprostaglandin F1α was found to be significantly related to the systolic blood pressure in 5- and 9-week-old rats of the three strains (r = 0.42; n = 71; P&lt;0.001).
4. These results exclude a primary role in the development of hypertension for a genetically determined defect in the renal biosynthesis of prostacyclin in the spontaneous hypertensive rat of the Lyon strain.