bluuebunny/crossref_metadata_2025_split huggingface dataset:
Changes in concentrations of respiratory components and cytochrome oxidase activity in mitochondria obtained from carbon tetrachloride-induced cirrhotic rat liver
Authors: Morimoto Taisuke , Tanaka Akira , Taki Yoshiro , Noguchi Masashi , Yokoo Naoki , Nishihira Tomohiko , Nishikawa Katsuhide , Yamamoto Shunji , Nitta Naoki , Jikkoh Akira , Kamiyama Yasuo , Yamaoka Yoshio , Ozawa Kazue 
Published: August 2015

1. Changes in the concentrations of respiratory components, phosphorylative activity, the cytochrome oxidase activity of mitochondria and the hepatic adenylate energy charge level (in situ) were studied in cirrhotic rat liver induced by carbon tetrachloride (CCl4).
2. In the cirrhotic liver mitochondria, concentrations of cytochrome a(+ a3), cytochrome b, coenzyme Q9 and coenzyme Q10 increased significantly to 2.44 ± 0.02 × 10−10 (mean ± se), 1.37 ± 0.05 × 10−10, 25.57 ± 0.47 × 10−10 and 5.39 ± 0.26 × 10−10 mol/mg of mitochondrial protein, respectively, compared with 1.83 ± 0.03 × 10−10, 1.22 ± 0.02 × 10−10, 16.24 ± 0.39 × 10−10 and 1·81 ± 0.07 × 10−10 in normal rats [P &lt; 0.001 for cytochrome a(+ a3), coenzyme Q9 and coenzyme Q10, and P &lt; 0.01 for cytochrome b].
3. Concentrations of flavoprotein and pyridine nucleotides decreased significantly to 13.33 ± 0.14 × 10−10 and 45.68 ± 1.59 × 10−10 mol/mg of mitochondrial protein, respectively, compared with 14.79 ± 0.33 × 10−10 and 86.26 ± 1.83 × 10−10 in normal rats (P &lt; 0.001). There was no significant difference in the concentration of cytochrome c(+ c1).
4. Cytochrome oxidase activity per unit of cytochrome a(+ a3) increased significantly to 67.43 ± 1.71 atoms O s−1 mol−1, compared with 55.77 ± 1.16 in normal rats (P &lt; 0.001). By contrast, phosphorylative activity per unit of cytochrome a(+ a3) decreased significantly in the cirrhotic liver to 10.40 ± 0.36 s−1 compared with 13.43 ± 0.49 in normal rats (P &lt; 0.001). The total adenine nucleotide concentration and the hepatic energy charge level decreased significantly in the cirrhotic liver to 3.420 ± 0.075 μmol/g of wet liver and 0.806 ± 0.003, respectively, compared with 3·854 ± 0.088 and 0.841 ± 0.004 in normal rats (P &lt; 0.001).
5. It is concluded that in mitochondria obtained from CCl4-induced cirrhotic rat liver in which the energy charge level is decreased, cytochrome oxidase activity per unit of cytochrome a(+ a3) is increased in association with an increase in cytochrome a(+ a3) concentration.
Inhibition of platelet aggregation and thromboxane production by low concentrations of aspirin in vitro
Authors: Sils D. , Rodgers S. E. , Lloyd J. V. , Wilson K. M. , Siebert D. M. , Bochner F. 
Published: August 2015

1. The aspirin concentrations previously reported to inhibit platelet aggregation in vitro (40–500 μmol/l) are much greater than those required in vivo in man (5 μmol/l).
2. Human platelet-rich plasma was incubated with buffer or various aspirin concentrations at 37°C for up to 4.5 h. Platelet aggregation and thromboxane generation were measured in response to collagen (0.4–6.3 μg/ml) and adenosine 5′-pyrophosphate (0.5–4 μmol/l).
3. The concentration of aspirin needed to inhibit platelet aggregation in response to a critical concentration of aggregating agent (lowest concentration to cause greater than 50% aggregation) was lower than that required for higher concentrations of aggregating agent.
4. With more prolonged incubation times with aspirin, lower concentrations of aspirin inhibited platelet aggregation.
5. Inhibition of platelet aggregation and thromboxane formation by 10 μmol/l aspirin was maximal by 90 min. There was progressive inhibition by 3 μmol/l aspirin during incubation for 270 min. By the end of this time there was also significant inhibition by 1 μmol/l aspirin.
6. The apparent discrepancy between inhibitory aspirin concentrations in vivo and those observed in vitro in previous studies appears to have been resolved by extending the incubation time of platelets with low aspirin concentrations, thus mimicking the conditions in vivo.
Glomerular and tubular handling of differently charged human immunoglobulin light chains by the rat kidney
Authors: Baylis Christine , Falconer-Smith James , Ross Brian 
Published: August 2015

1. To examine the effect of charge and molecular size on the renal handling of immunoglobulin light chain, three different human light chains were purified, iodinated and characterized with regard to molecular weight and isoelectric point. The molecular weights were similar, whereas the isoelectric points ranged from markedly cationic to markedly anionic.
2. Renal handling of the light chains was determined in vivo in the Munich–Wistar rat and in vitro in the isolated perfused rat kidney.
3. Significant restriction to the transglomerular passage of all three light chains was evident in the intact kidney, with the most anionic light chain being restricted most while the cationic light chain was restricted least. The charge dependence of filtration of these naturally occurring proteins was, however, much less pronounced than has previously been reported for the synthetic dextrans.
4. Tubular reabsorption of the three light chains was quite variable in the intact kidney and did not appear to be related to molecular charge. In the isolated perfused kidney, once account had been taken of the abnormally high rate of filtration of these proteins, the reabsorption of the three light chains was strikingly similar to that seen in vivo.
5. With these three purified human light chains no marked influence of charge (pI) has been demonstrated in vivo or in vitro, for glomerular restriction or renal tubular reabsorption. Some other properties of human myeloma light chains may determine their renal handling and nephrotoxicity.
Atrial natriuretic peptide and total exchangeable body sodium: Relationships in rats with chronic myocardial infarction
Authors: Hodsman G. P. , Harrison R. W. , Sumithran E. , Johnston C. I. 
Published: August 2015

1. The relationship between plasma atrial natriuretic peptide (ANP) and body sodium was determined in rats 1 month after myocardial infarction induced by coronary artery ligation. After operation rats received a normal or a low salt diet, and total exchangeable body sodium was measured sequentially.
2. Rats with infarction receiving a normal salt intake did not retain sodium when compared with sham-operated controls. Rats receiving a low salt diet had a 10% decrease in body sodium (P &lt; 0.01). The decrease was the same in rats with infarction as in controls.
3. Plasma ANP was similar in control rats irrespective of salt status. Plasma ANP levels were markedly elevated in rats with infarction irrespective of salt status (P &lt; 0.01).
4. The rise in plasma ANP was correlated with cardiac hypertrophy and infarct size in animals fed both normal and low salt diets. However, there was no relationship between plasma ANP and exchangeable body sodium.
5. These results suggest that in this model of heart failure plasma ANP is raised by increased left atrial stretch in proportion to the severity of left ventricular dysfunction. In contrast, plasma ANP concentrations do not appear to be elevated as a consequence of increased right atrial pressure caused by sodium retention and expanded extracellular volume.
An assessment of a double-isotope method for the detection of transferrin accumulation in the lungs of patients with widespread pulmonary infiltrates
Authors: Rocker G. M. , Pearson D. , Stephens M. , Shale D. J. 
Published: August 2015

1. The accumulation in the lung of the plasma protein transferrin was determined in 44 patients with widespread pulmonary infiltrates of various causes and in 11 healthy volunteers using a double-isotope method based on labelling in vivo of circulating transferrin with indium and erythrocytes with technetium.
2. In 22 patients meeting criteria for the adult respiratory distress syndrome (ARDS) the mean transferrin accumulation rate was threefold greater (P &lt; 0.005) than in 22 patients not meeting these criteria, although most possessed an appropriate risk factor for ARDS, in addition to extensive radiographic changes.
3. The double-isotope method did not completely separate patients with ARDS from those not meeting the criteria or from control subjects and cannot be considered a diagnostic test for the condition. Statistically significant rates of transferrin accumulation, however, occurred more frequently in patients with ARDS (82%) than in controls (64%) or in those without ARDS (59%).
Elevated protein requirements in cirrhosis of the liver investigated by whole body protein turnover studies
Authors: Swart G. R. , van den Berg J. W. O. , Wattimena J. L. D. , Rietveld T. , Van Vuure J. K. , Frenkel M. 
Published: August 2015

1. In patients with cirrhosis of the liver and in healthy control subjects, the rates of nitrogen flux, protein synthesis and protein breakdown were studied, using a single oral dose of 200 mg of [15N]glycine as a tracer. The nitrogen flux through the amino acid pool was measured separately with both urinary ammonia and urinary urea as end products; the average value was used for further calculations.
2. Subjects were studied in the fed state, both on an adequate and a protein-restricted diet, and also in the fasting state.
3. The rates of protein synthesis were markedly increased in the patients, not only in the fed but also in the fasting state. Protein breakdown rates were increased in the patients in the fed state.
4. The nitrogen balance in steady-state conditions in the fed state was more positive in the patients, while their nitrogen loss in the fasting state was no higher than that of control subjects.
5. A hypothesis is put forward that the high protein requirements of cirrhotic patients could be caused by small and inadequate liver glycogen stores; due to these small stores, gluconeogenesis from amino acids will take place and lead to an extra amino acid loss even during short-term fasting. This increased amino acid loss could explain the elevated protein requirements in cirrhotic patients.
Does resection enhance the response of the intestine to urogastrone-epidermal growth factor in the rat?
Authors: Goodlad R. A. , Savage A. P. , Lenton W. , Ghatei M. A. , Gregory H. , Bloom S. R. , Wright N. A. 
Published: August 2015

1. The objective of this study was to see whether another proliferative stimulus could modify the marked proliferative effect of human epidermal growth factor (urogastrone-epidermal growth factor, URO-EGF) on the gastrointestinal epithelium.
2. The response of the gastrointestinal tract to URO-EGF was investigated in rats maintained on total parenteral nutrition (TPN) with or without 75% small bowel resection.
3. Continuous infusion of 60 μg of recombinant β-urogastrone/day per rat increased proliferation in the stomach by over four times (P &lt; 0.01), doubled proliferation in the small intestine (P &lt; 0.001) and increased it by four and a half times in the colon (P &lt; 0.001) in the control group. No significant effect of urogastrone was observed in the stomach of the resected groups, but proliferation was also increased in the small intestine by one and a half times (P &lt; 0.001) and by nearly four times in the colon (P &lt; 0.001).
4. Two-way analysis of variance showed that resection had a significant effect (P &lt; 0.01) on proliferation below the anastamosis and in the ileum. However, the response of the ileum was only half that observed in orally fed rats, which confirms the importance of ‘luminal nutrition’ in the response to resection.
5. Intestinal resection in the TPN rat was associated with a small rise in plasma enteroglucagon levels, suggesting that this hormone may be implicated in the adaptive response of the small intestine to resection. However, the proliferative effects of URO-EGF were not associated with increased plasma enteroglucagon and thus the two agents probably exert their proliferative effects via separate mechanisms.
6. There was no evidence for a significant positive interaction between the effects of URO-EGF and resection. Thus loss of intestinal mass had no influence on the susceptibility of the intestine to the effects of URO-EGF. Although URO-EGF significantly increased intestinal epithelial cell proliferation, it could not entirely compensate for the lack of luminal contents.
Intestinal ion transport in rats with spontaneous arterial hypertension
Authors: Lübcke Ralf , Barbezat Gilbert O. 
Published: August 2015

1. Ion balance, intestinal ion transport in vivo with luminal Ringer, and direct voltage clamping in vivo with luminal Ringer and sodium-free choline-Ringer were studied in young (40 days old) and adult (120 days old) spontaneously hypertensive rats (SHR) and age-matched normotensive controls (Wistar–Kyoto rats, WKY).
2. Faecal sodium output was significantly higher in SHR compared with WKY in both young (+ 67%) and adult (+ 43%) rats.
3. Small-intestinal sodium absorption was equal in young SHR and WKY, but significantly greater net sodium absorption was found in the ileum of adult SHR. In contrast, net sodium absorption was reduced from the colon of both young and adult SHR.
4. In adult SHR, the colonic transepithelial short-circuit current (Isc) and the transepithelial potential difference (PD) were significantly higher, whereas the transepithelial membrane resistance (Rm) was significantly lower than in WKY. There was an identical drop in Isc in both strains when luminal sodium was replaced by choline. These data cannot be explained by increased electrogenic cation (sodium) absorption in the SHR, but would favour chloride secretion.
5. It is suggested that in SHR membrane electrolyte transport abnormalities may also be present in the epithelial cells of the small and large intestine, as have been demonstrated already in blood cells by several investigators. The SHR may become an interesting experimental animal model for the study of generalized ion transport disorders.
Serum carnosinase activities in patients with alcoholic chronic skeletal muscle myopathy
Authors: Duane P. , Peters T. J. 
Published: August 2015

1. Serum carnosinase activity was assayed in a group of alcoholic patients with and without histologically proven atrophy of type II skeletal muscle fibres, and in control subjects. No significant activity was detected in muscle biopsy samples or washed erythrocytes.
2. Serum carnosinase activity was significantly lower in chronic alcoholic patients compared with a group of age-matched controls. Alcoholics with abnormal muscle biopsies had significantly lower enzyme activities than either those patients with normal muscle biopsies or the controls. Serum enzyme activities in patients with normal muscle biopsies were not significantly different from controls.
3. Serum carnosinase activity was inversely correlated with the degree of muscle atrophy as measured by the type II fibre atrophy factor. There was a positive correlation between the enzyme activity and skeletal muscle mass as reflected by the creatinine-height index. Furthermore, the enzyme activity significantly increased, with resolution or improvement in the myopathy, in patients who abstained from alcohol.
4. Kinetic studies showed that the reduced carnosinase activity was due mainly to a decrease in the apparent Vmax. The apparent Km was significantly higher in the myopathic compared with non-myopathic alcoholics. Mixing serum from controls and patients with myopathy gave the expected values, indicating the absence of a serum enzyme inhibitory factor. Acute alcohol loading had no effect on the serum carnosinase activity.
5. The decrease in serum carnosinase activity in alcoholics was not related to the severity of their liver disease. Assays of serum carnosinase in chronic alcoholics can thus be used as a marker of their associated myopathy.
Autonomic control of heart rate during dynamic exercise in human hyperthyroidism
Authors: Maciel Benedito C. , Gallo Lourenco , Marin Neto Jose A. , Maciel Lea M. Z. , Martins Luiz E. B. 
Published: August 2015

1. The relative contribution of the sympathetic and parasympathetic components of the autonomic nervous system to the regulation of the chronotropic reponse to dynamic exercise was evaluated indirectly in nine patients with thyrotoxicosis and in seven normal volunteers. All subjects were women, with equivalent ages in both groups. Six of the nine patients with hyperthyroidism were reevaluated after clinical compensation of the disease with propylthiouracil.
2. Heart rate responses were evaluated during discontinuous dynamic effort maintained for 4 min on a bicycle ergometer at levels of 5, 15, 25 and 50 W, and also of 75 W in normal individuals. The study was also performed under conditions of sympathetic pharmacological blockade with propranolol (0.2 mg/kg body weight).
3. Even though the magnitude of the total increase in heart rate evoked by each level of dynamic exercise was equivalent in normal and hyperthyroid patients, the tachycardiac response occurring at the beginning of the exercise, which depends on a predominantly vagal mechanism, was substantially different from that observed after 30 s of effort, when sympathetic contribution becomes more important. The hyperthyroid patients showed considerably lower increases in heart rate than the normal individuals during the initial 30 s of effort, with the opposite occurring from this moment onward.
4. In the hyperthyroid patients, β-adrenergic blockage depressed tachycardia after 30 s of effort at the 15 and 50 W levels, whereas in normal individuals this effect was only manifested at 50 and 75 W.
5. The patients who obtained clinical compensation showed a pattern of chronotropic response which tended to be close to that shown by normal subjects.
6. These data demonstrate depression of the capacity for vagal withdrawal during exercise in hyperthyroid patients, in association with a greater activation of the sympathetic component in relation to normal subjects. These functional modifications seem to be at least partially reversible when the patients are controlled clinically with anti-thyroid drugs.
Utilization for protein synthesis of 2-ketoisocaproate relative to utilization of leucine, as estimated from exhalation of labelled CO2
Authors: Imura Kenji , Shiota Tetsuya , Swain Louis M. , Walser MacKenzie 
Published: August 2015

1. We have previously shown that the ratio (RWBP) of incorporation of label from 2-ketoisocaproate (KIC) into the leucine of whole-body protein to the simultaneous incorporation of label from leucine itself into protein is a measure of the nutritional efficiency of KIC as a substitute for leucine.
2. In order to determine whether RWBP can be estimated indirectly from measurement of labelled CO2 excretion, rats were injected orally or intravenously with [4,5-3H]leucine and either [1-14C]leucine or [1-14C]KIC. Expired CO2 was collected for 6 h.
3. The results show that 9–14% of KIC underwent first-pass oxidation after oral administration. When isotopes were given intravenously, the mean rate of excretion of 14CO2 from KIC, after 20 min, remained 1.8 times the mean rate of excretion of 14CO2 from leucine.
4. Mean RWBP, measured in whole-body protein in rats given isotopes orally or intravenously along with small or large doses of carriers, was the same as mean RWBP estimated from mean cumulative CO2 excretion.
5. We conclude (1) that nutritional efficiency of KIC relative to leucine can be estimated from measurement of labelled CO2 excretion, and (2) that the relative inefficiency of KIC as a substitute for leucine in the rat is attributable to first-pass oxidation of 9–14% (when given orally) and 80% greater susceptibility to systemic oxidation than leucine.
Potent and comparable vasodilator actions of A- and B-calcitonin-gene-related peptides on the superficial subcutaneous vasculature of man
Authors: Williams Gareth , Cardoso Helena , Ball Joanna A. , Mulderry Peter K. , Cooke Ernest , Bloom Stephen R. 
Published: August 2015

1. Vasoactivity of human A- and B-calcitonin-gene-related peptides was studied in normal subjects, using reflectance plethysmography to measure relative changes in blood flow produced by superficial subcutaneous injections of the peptides.
2. Injection of 10−11 mol of either peptide caused an immediate 200% increase in local blood flow and prolonged hyperaemia lasting up to 3 h. The hyperaemic response to 10−13 mol of each peptide was significantly (P &lt; 0.01) smaller and shorter in duration than that elicited by 10−1 mol of the same peptide, and 10−15 mol of both peptides produced no hyperaemia other than that attributable to needle insertion alone.
3. At all three dosages examined, there were no significant differences between A- and B-calcitonin-gene-related peptides in magnitude or time course of the hyperaemic response.
4. Human A- and B-calcitonin-gene-related peptides are therefore potent vasodilators in man, causing comparable dose-related vasodilatation in the superficial tissues.
Effect of gut-derived acetate on glucose turnover in man
Authors: Scheppach W. , Wiggins H. S. , Halliday D. , Self R. , Howard J. , Branch W. J. , Schrezenmeir J. , Cummings J. H. 
Published: August 2015

1. The effect of acetate absorbed from the gut on glucose turnover has been determined in four healthy subjects during both fasting and an intravenous glucose infusion by using [U-13C]glucose.
2. In the first part of the study, after an overnight fast, a tracer dose of [U-13C]glucose was infused at a constant rate along with an infusion of saline for 7 h. In the second part the saline infusion was replaced by glucose at 4.25 mg min−1 kg−1. In both studies 15 mmol of sodium acetate was given by mouth at 15 min intervals from the fourth to the sixth hour. Glucose turnover, respiratory quotient, metabolic rate and blood levels of acetate, 3-hydroxybutyrate, lactate, insulin, glucagon and gastric inhibitory polypeptide were measured.
3. Glucose turnover rates (means ±sem) were 1.88 ±0.1 mg min−1 kg−1 during fasting and 4.0 ± 0.08 mg min−1 kg−1 during glucose infusion. Acetate had no effect on glucose turnover, insulin, glucagon and gastric inhibitory polypeptide levels, but temporarily halted the rise in free fatty acids seen during the fasting study. No changes in oxygen consumption or carbon dioxide output occurred, in keeping with previous observations that acetate substitutes for lipid oxidation during metabolism and has no direct effect on glucose turnover.
Comparison between the cellobiose/mannitol and 51Cr-labelled ethylenediaminetetra-acetate absorption tests in the detection of coeliac disease
Authors: Martines D. , Morris A. I. , Gilmore I. T. , Williams A. , Stockdale H. , Critchley M. , Smith G. A. , Billington D. 
Published: August 2015

1. The cellobiose/mannitol and 51Cr-labelled ethylenediaminetetra-acetate (51Cr-EDTA) absorption tests have been compared with respect to their ability to detect altered intestinal permeability in coeliac disease.
2. In patients with clinically proven coeliac disease, 13 out of 14 (93%) had abnormal urinary cellobiose/mannitol ratios, while only five out of 12 (42%) had abnormal urinary recoveries of 51Cr-EDTA. Thus, the cellobiose/mannitol absorption test is more sensitive in recognizing coeliac disease and this difference was significant (P &lt; 0.02).
3. Possible reasons for this difference in the sensitivity of the two absorption tests are discussed.