bluuebunny/crossref_metadata_2025_split huggingface dataset:
Tubular prostaglandin E2 production and its role in urinary hypotonicity after release of ureteral occlusion in the rat
Authors: Torikai Shozo 
Published: August 2015

1. In order to explore the involvement of endogenous prostaglandin E2 (PGE2) in the urine concentration defect after ureteral occlusion, PGE2 production by isolated collecting ducts in vitro and effects of indomethacin on urine osmolality in vivo were examined.
2. Twenty-four hours ureter obstruction caused increased PGE2 production by the medullary collecting ducts, which was maintained at a high level on the day after release of obstruction (0.8 ± 0.2 pg/mm normal, 8.1 ± 0.9 pg/mm 24 h obstruction, and 6.6 ± 1.0 pg/mm post-obstruction, mean ± sem). An enhanced PGE2 production was also observed for papillary collecting duct on the day after release of 24 h ureteral occlusion (3.9 ± 0.5 pg/mm normal and 7.7 ± 1.2 pg/mm post-obstruction).
3. Administration of indomethacin to the unilateral post-obstructive rats slightly raised the urine osmolality of the post-obstructed kidney (from 339 ± 17 to 390 ± 22 mosmol/kg H2O), while it had a greater effect on the contralateral intact kidney (from 1569 ± 138 to 2567 ± 198 mosmol/kg H2O).
4. Our data may indicate that the urine concentration defect after 24 h ureteral occlusion is ascribable mainly to a mechanism other than increased endogenous PGE2.
Are lymphocyte β-adrenoceptors altered in patients with cystic fibrosis?
Authors: Feldman Ross D. , Fick Robert B. , McArdle Wendy , Lai Cynthia C.-Y. 
Published: August 2015

1. β-Adrenergic responsiveness may be decreased in cystic fibrosis. In order to determine whether this reflects an alteration in the human lymphocyte β-receptor complex, we studied 12 subjects with cystic fibrosis (six were stable and ambulatory and six were decompensated, hospitalized) as compared with 12 normal controls.
2. Lymphocyte β-receptor mediated adenylate cyclase activity (EC 4.6.1.1) was not decreased in the ambulatory cystic fibrosis patients as compared with controls. In contrast, decompensated hospitalized cystic fibrosis patients demonstrated a significant reduction in β-receptor mediated lymphocyte adenylate cyclase activity expressed as the relative increase over basal levels stimulated by the β-agonist isoprenaline compared with both normal controls and stable ambulatory cystic fibrosis patients (control 58 ± 4%; ambulatory cystic fibrosis patients 51 ± 7%; decompensated hospitalized cystic fibrosis patients 28 ± 5%; P &lt; 0.05).
3. Our data suggest that defects in lymphocyte β-receptor properties in cystic fibrosis patients may be better correlated with clinical status than with presence or absence of the disease state.
Serum bile acid profile in thyroid dysfunction and effect of medical treatment
Authors: Kosuge Tomoo , Beppu Tomoe , Kodama Takao , Hidai Koh , Idezuki Yasuo 
Published: August 2015

1. Serum non-esterified bile acid profile was examined in patients with thyroid dysfunction. Sixteen hyperthyroid patients, six hypothyroid patients, nine patients taking thyroid or antithyroid drugs and 26 healthy controls were studied. The medicated patients were euthyroid when serum samples were collected. Bile acid concentration was determined by the simplified microassay method involving mass fragmentation spectrometry.
2. The sum of the concentrations of the individual bile acids was not significantly different among the four groups. However, the composition of bile acid reflected the thyroid function. The most prominent bile acid was deoxycholic acid in the hypothyroid patients and chenodeoxycholic acid in the hyperthyroid patients. The serum bile acid profile of medically treated patients was similar to that of normal cpntrols. The ratio of the sum of deoxycholic and cholic acid to that of lithocholic and chenodeoxycholic acid was found to be a good indicator of thyroid function, while the ratio of cholic acid to chenodeoxycholic acid correlated poorly with it.
3. The characteristic effect of thyroid hormone on the serum bile acid composition in man was the shift from the ‘family’ of cholic acid to that of chenodeoxycholic acid. This is in agreement with experimental results in the rat, and suggests a specific action of thyroid hormone on the hydroxylating enzymes involved in the conversion of cholesterol into bile acids.
The effect of weight loss, operation and parenteral nutrition on fat clearance in patients with colorectal cancer
Authors: Wilson A. W. , Kirk C. J. C. , Goode A. W. 
Published: August 2015

1. Fractional fat clearance rate (K2) in 21 patients with colorectal cancer was studied using the intravenous fat tolerance test.
2. K2 showed a negative correlation with weight change(r = −0.736, P &lt; 0.001) with the tumour in situ.
3. Fourteen patients were retested 12 weeks after curative resection of their tumours. Eight of the fourteen patients had raised K2 values pre-operatively; in all these the K2 values were reduced post-operatively (pre-operative median 3.94%/min, range 2.63–7.20%/min, postoperative median 2.31%/min, range 1.57–5.36%/min, P &lt; 0.01 by Wilcoxon's signed rank test). A high preoperative K2 value was associated with a large reduction in K2 post-operatively (r = − 0.844, P &lt; 0.001).
4. Seven patients with relatively high K2 values received a pre-operative course of intravenous nutrition after which K2 values were significantly reduced (pre-feeding median 7.20%/min, range 4.72–12.12%/min, post-feeding median 4.44%/min, range 2.17–6.83%/min, P &lt; 0.05).
Haemodialysis-associated amyloidosis: β2-microglobulin alone or associated with globin chains?
Authors: Argiles A. , Mourad G. , Axelrud-Cavadore Claude , Derancourt J. , Adell J. Jauregui , Mion C. , Cavadore J. C. 
Published: August 2015

1. The protein constituents of amyloid fibrils were characterized in amyloid deposits extracted from surgical material obtained from a 66-year-old patient undergoing maintenance haemodialysis and operated for a carpal tunnel syndrome.
2. Sodium dodecyl sulphate/polyacrylamide-gel electrophoresis disclosed the presence of bands at 12 and 14 kDa. Two-dimensional electrophoresis and Western blotting confirmed that the proteins were β2-microglobulin (β2M) and globin chains.
3. When the effluent of high-performance gel filtration chromatography corresponding to molecular masses of 10–15 kDa was subjected to Edman degradation, only one amino acid residue was found at each step. The 18 residues determined corresponded to the N-terminal sequence of β2M.
4. Although globin chains were clearly present in the amyloid material, they were not accessible for sequence determination. The identification of the other protein constituents present in the amyloid material, along with β2M, should provide a better understanding of haemodialysis-associated amyloidosis, the mechanisms of formation of which have not yet been completely determined.
Evidence for γ-aminobutyric acid as the inhibitor of γ-aminobutyric acid binding in the plasma of humans with liver disease and hepatic encephalopathy
Authors: Levy L. J. , Leek J. , Losowsky M. S. 
Published: August 2015

1. Gas–liquid chromatography and a radioreceptor assay were used to measure plasma γ-aminobutyric acid (GABA) in patients with liver disease and hepatic encephalopathy.
2. There was a significant correlation between the results obtained by the two methods, and compared with controls plasma GABA was elevated.
3. These findings suggest that the increased GABA binding inhibitory activity of plasma of these patients is probably due to GABA itself.
Endothelium-dependent relaxation in isolated human arteries and veins
Authors: Thom S. , Hughes A. , Martin G. , Sever P. S. 
Published: August 2015

1. The role of the endothelium in mediating relaxation to acetylcholine, the calcium ionophore A23187, vasoactive intestinal peptide and peptide histidine methionine was studied using isolated human blood vessels.
2. Segments of renal, colic, pulmonary, uterine, transverse cervical, brachial, coronary and coeliac branch arteries, and saphenous veins, were obtained from surgical resection material for use in tissue bath studies.
3. Acetylcholine or A23187 produced endothelium-dependent relaxation in isolated vessels from all vascular beds studied. Coronary arteries, however, differed in their response to acetylcholine which produced predominantly a contractile response, either alone or after initial relaxation.
4. Vasoactive intestinal peptide and peptide histidine methionine produced endothelium-dependent relaxation in coeliac branch arteries. However, these peptides relaxed isolated pulmonary arteries independently of endothelium.
5. Endothelium-dependent relaxation in response to acetylcholine and A23187 was antagonized by nordihydroguaretic acid, a lipoxygenase inhibitor, and methylene blue and haemoglobin, inhibitors of soluble guanylate cyclase. In these respects the endothelium-dependent responses of human arteries to acetylcholine and A23187 resemble those described in other species.
The response of intracellular and surface ferritin after T-cell stimulation in vitro
Authors: Pattanapanyasat K. , Hoy T. G. , Jacobs A. 
Published: August 2015

1. Measurements of T-lymphocyte surface ferritin using flow cytometry show that phytohaemagglutinin (PHA) stimulation causes a marked increase in the number of cells bearing spleen-type (S) and heart-type (H) ferritin on their membrane, whereas no such change occurs in non-stimulated cells. This coincides with increases in interleukin-2 receptors, transferrin receptors and HLA-DR antigen.
2. There is an increase in the intracellular concentration of both S- and H-ferritin in lymphocytes after PHA stimulation: H-ferritin increases five- to seven-fold, but S-ferritin only two- to three-fold. The maximum H/S ratio is about 15/1. However, these increases also occur in cells cultured in the absence of PHA.
3. Small amounts of both S- and H-ferritin are released into the medium, especially from stimulated cells, but the H/S ratios are lower than intracellular ratios.
4. The present findings suggest that lymphocyte stimulation followed by ferritin synthesis is accompanied by an increase in the amount of intracellular and cell surface ferritin and, possibly, the amount released from the cells.
Peripheral vascular responses during carotid baroreceptor stimulation in normotensive and hypertensive subjects
Authors: Duprez D. , De Pue N. , Clement D. L. 
Published: August 2015

1. The carotid baroreceptors were stimulated for 2 min by neck suction at −30 and −60 mmHg in 19 normotensive subjects and 12 patients with moderate essential hypertension.
2. Blood pressure was measured with a mercury sphygmomanometer and heart rate was derived from beat-to-beat analysis of the electrocardiogram. Blood flow was measured simultaneously at calf and finger with venous occlusion plethysmography and the vascular resistance was calculated.
3. During neck suction at − 30 and − 60 mmHg there was a significant decrease in arterial blood pressure and heart rate. There was a transient vasodilatation of the calf blood vessels, while there was a sustained vasoconstriction of the finger blood vessels. These results were qualitatively similar in both groups; however, there were quantitative differences.
4. These experiments show that there is a selective autonomic control of the different peripheral vascular beds by the carotid baroreceptors in both normotension and mild essential hypertension.
Prostanoid synthesis by isolated rat glomeruli: Effect of oestrous cycle and pregnancy
Authors: Gregoire I. , Dupouy J. P. , Fievet P. , Sraer J. D. , Fournier A. 
Published: August 2015

1. An increase in glomerular prostaglandin (PG) synthesis has been reported in two experimental models of increased glomerular filtration rate (GFR).
2. Because pregnancy, in women and rats, is also associated with an increased GFR, we studied PG biosynthesis by glomeruli isolated from pregnant rats in comparison with virgin rats at the different phases of the oestrous cycle.
3. PGE2 and PGF2α synthesis markedly increased during pregnancy (at day 21 of gestation a five- to sevenfold increase of PGE2 and PGF2α was seen; at day 15 of gestation a threefold increase of PGE2 and a sixfold increase of PGF2α was noted). However, thromboxane A2 (TXA2) synthesis was similar in all the groups studied.
4. Among the four phases of the oestrous cycle, dioestrus was characterized by a significant increase in glomerular synthesis of PGE2.
5. The fact that during pregnancy the increase in the vasodilator PGE2 is not counteracted by an increase in the constrictor TXA2 must be taken into account when explaining the glomerular hyperfiltration which characterizes the pregnant state.
6. The increase of PGE2 synthesis during dioestrus should be considered in studies of PG synthesis using virgin rats as controls.
Cardiovascular responses to upright tilting in healthy subjects
Authors: Hainsworth R. , Al-Shamma Y. M. H. 
Published: August 2015

1. The cardiovascular responses to passive upright tilting were determined in healthy human subjects of various ages using entirely ‘non-invasive’ techniques. Cardiac output was determined by a single breath method and arterial blood pressure by an automatic sphygmomanometer.
2. Steady-state responses were achieved within 4–6 min from the onset of the tilt and were maintained for at least 15 min.
3. The reproducibilities of the responses to tilting by 60°, expressed as two standard deviations of the differences between responses on two occasions (mean responses in parentheses), were: cardiac output ±0.70 (−1.41) litre/min, heart rate ±7.6 (+ 14.7) beats/min, systolic blood pressure ± 15.5 (+ 1.0), and diastolic blood pressure μ13.1 (+ 13.6)mmHg.
4. Tilting by 20° resulted in no significant responses but between 20° and 60° responses were linearly related to the angle of tilt.
5. Supine values and responses to tilting by 60° were compared in subjects in four age groups between 20 and 80 years. With increasing age, the supine values of cardiac output declined and those of arterial blood pressures increased. Responses of heart rate, cardiac output and diastolic pressure declined by increasing age. These results, obtained from a healthy population, provide reference values for comparison with individuals who may have deficient postural responses.
Alveolar carbon monoxide: A comparison of methods of measurement and a study of the effect of change in body posture
Authors: Kirkham Andrew J. T. , Guyatt Andrew R. , Cumming Gordon 
Published: August 2015

1. We have compared rebreathing, breath-hold and mean alveolar methods of measuring alveolar carbon monoxide (CO), at levels similar to those found in smokers, as a preliminary to using them as indirect measures of carboxyhaemoglobin levels. In the present study alveolar CO levels were raised by rebreathing a 2% CO mixture.
2. Breath-hold CO was measured after breath-hold times of 0–35 s in 5 s increments. Using generalized linear models, the maximum value for breath-hold CO was estimated to occur at 23 s. Breath-hold CO after a 20 and 25 s breath-hold were similar to and significantly greater than those of less than 20 s or greater than 25 s.
3. As expired CO increased, the difference between breath-hold and mean alveolar CO became proportionally larger. On average, breath-hold CO was 24% larger than mean alveolar CO.
4. Rebreathing, breath-hold and mean alveolar CO were compared at four different inspired oxygen concentrations. Expired CO increased significantly with increasing oxygen for all three methods. At end-tidal oxygen levels of less than 25%, breath-hold and rebreathing CO were similar, however, the overall mean difference between the three methods was significant.
5. While rebreathing CO was unaffected by changes in ventilation/perfusion of the lung, induced by change in body posture, both breath-hold and mean alveolar CO showed a significant fall with change from the supine to erect posture.
6. We conclude that under normoxic conditions, rebreathing and breath-hold CO (20 or 25 s breath-hold) were similar, whereas the mean alveolar method produced significantly lower values, presumably due to lack of equilibration. Altering ventilation/perfusion of the lung caused no mean change in the measurement of rebreathing CO but did affect the other methods.
A comparison of the renal actions of γ-l-glutamyl-l-dopa and γ-l-glutamyl-l-tyrosine in normal man
Authors: Jeffrey R. F. , MacDonald T. M. , Lee M. R. 
Published: August 2015

1. The renal responses to the dipeptides γ-l-glutamyl-l-dopa (gludopa) and γ-l-glutamyl-l-tyrosine (glutyrosine) were compared when given intravenously in six normal male volunteers.
2. Gludopa is natriuretic and diuretic at a dose of 25 μg min−1 kg−1. At the same dose, glutyrosine had no effect on the volume or sodium content of the urine.
3. There was a 400-600-fold increase in urine dopamine output after gludopa; there was no conversion of glutyrosine to dopamine.
4. Gludopa significantly inhibited plasma renin activity, whereas with glutyrosine there was a non-significant increase.
5. Gludopa is a potent pro-drug for renal dopamine production and exerts natriuretic and hormonal effects. Glutyrosine appears to be inactive. The results support the contention that circulating l-dopa is the important physiological precursor for renal dopamine.
Effect of plasma from hypertensive subjects on Ca2+ transport in permeabilized human neutrophils
Authors: Zidek Walter , Sachinidis Agapios , Spieker Claus , Storkebaum Walter 
Published: August 2015

1. The effects of plasma fractions from essential hypertensive subjects (n = 14) and normotensive subjects (n = 14) on Ca2+ transport in permeabilized human neutrophils was studied using an ion-selective electrode.
2. Plasma fractions were obtained by gel filtration and contained substances with a molecular mass in the range 1000–1500 daltons. This fraction isolated from essential hypertensive subjects has been shown to increase blood pressure after intravenous injection in the rat.
3. The rate of Ca2+ uptake by permeabilized neutrophils after addition of extracellular Ca2+ was significantly accelerated during incubation of the cells with the hypertensive fraction (1049.3 ±807.7% vs 242.5 ±320.9% of the control value, mean ± sd, P &lt; 0.05).
4. It is concluded that the hypertensive plasma fraction increases Ca2+ accumulation in subcellular particles, so that under excitatory conditions Ca2+ release in arterial smooth muscle might be enhanced.
Abnormalities of sodium transport by sodium, potassium-activated adenosine triphosphatase in erythrocytes from obese children
Authors: Dianzani Irma , Boero Roberto , Guarena Cesare , Urbino Antonio , Corda Giuliana , Quarello Francesco , Cerutti Franco 
Published: August 2015

1. Intracellular Na+ concentration [Na+]i and Na+ extrusion catalysed by sodium, potassium-activated adenosine triphosphatase (Na+, K+-pump) were evaluated in erythrocytes from 21 obese children and 20 normal weight- and age-matched controls.
2. Obese children showed a significantly decreased Vmax for Na+, K+-pump-mediated Na+ efflux (5638 ± 338 vs 7597 ±335 μmol h−1 litre−1 of cells mean±SEM, P = 0.01), while [Na+]i (9.3±0.3 vs 9.1 ± 0.5 mmol/litre of cells, mean±SEM, NS) and Na+ efflux in fresh cells (2380± 153 vs 2533 ± 180 μmol h−1 litre−1 of cells, mean ±sem, NS) were similar in both groups.
3. Mean diastolic blood pressure was significantly higher in obese children than in controls, although both groups were normotensive (73.8 ± 1.3 vs 66.2 ±1.9 mmHg, mean ± sem, P = 0.009).
4. Abnormal Na+, K+-pump activity is present in individuals with idiopathic obesity.
5. The possible link between obesity and blood pressure regulation may be mediated through modifications in Na+, K+-pump activity.
A study of the structure of the gene for lecithin: Cholesterol acyltransferase in four unrelated individuals with familial lecithin: Cholesterol acyltransferase deficiency
Authors: Humphries S. E. , Chaves M. E. , Tata F. , Lima V. L. M. , Owen J. S. , Borysiewicz L. K. , Catapano A. , Vergani C. , Gjone E. , Clemens M. R. , Williamson R. , McIntyre N. 
Published: August 2015

1. We have used polyclonal antibodies and a complementary DNA clone for human lecithinxholesterol acyltransferase (LCAT) to study LCAT protein and the structure of the LCAT gene, respectively, in patients with familial LCAT deficiency from Norway, Ireland, Germany and Italy.
2. The patients had low levels of non-functional LCAT protein in their serum as measured by rocket Immunoelectrophoresis; its mol. wt. of approximately 68 000 was identical with that of LCAT in normal plasma, as judged by immunoblotting.
3. Enzymatic digestion of DNA samples from the patients produced LCAT gene fragments which were indistinguishable from those found in normal individuals.
4. We conclude that LCAT deficiency in these patients is not caused by a large deletion or rearrangement of the LCAT gene sequences.
Contrasting effects of intravenous and oral etidronate on vitamin D metabolism in man
Authors: Lawson-Matthew P. J. , Guilland-Cumming D. F. , Yates A. J. P. , Russell R. G. G. , Kanis J. A. 
Published: August 2015

1. We have studied the early effects of intravenously and orally administered etidronate on vitamin D metabolism and indirect indices of calcium and skeletal metabolism in 17 patients with Paget's disease of bone.
2. Administration of etidronate by mouth (700–1400 mg daily for 1 month) or its intravenous infusion (300 mg daily for 5 days) decreased bone resorption as judged by urinary excretion of hydroxyproline and significantly increased renal tubular reabsorption of phosphate. No significant change in serum activity of alkaline phosphatase was noted with either regimen.
3. When etidronate was given by mouth there was a progressive decrease in fasting urinary calcium excretion and a rise in serum 1,25-dihydroxyvitamin D3 [1,25-(OH)2D3]. In contrast, intravenous etidronate decreased serum values of l,25-(OH)2D3 and was associated with a progressive increase in fasting calcium excretion, suggesting a decrease in the net influx of calcium from the extracellular compartment to bone. Significant inverse correlations were noted between the change induced in 1,25-(OH)2D3 values at 2 weeks and the changes in serum calcium, phosphate and fasting urinary excretion of calcium.
4. These observations suggest that the different effects of intravenous and oral etidronate on l,25-(OH)2D3 values are a consequence of different doses of etidronate used and the different effects of these regimens on the accretion of calcium into bone.
Skeletal muscle glutamine production in thermally injured rats
Authors: Ardawi M. Salleh M. 
Published: August 2015

1. The effect of thermal injury (33–35% of body surface area) on the regulation of glutamine metabolism was studied in skeletal muscles of rats 7 days after injury.
2. Injury increased the rates of glutamine production in muscle, skin and adipose tissue preparations, with muscle production accounting for over 90% of total glutamine produced by the hindlimb.
3. Injury produced decreases in the concentrations of skeletal muscle glutamine (36%, P &lt; 0.001), glutamate (39%, P &lt; 0.001), alanine (24%, P &lt; 0.001), pyruvate (35%, P &lt; 0.001), 2-oxoglutarate (51%, P &lt; 0.001) and adenosine 5′-triphosphate (38%, P &lt; 0.001). The concentrations of ammonia (42%, P &lt; 0.001) and inosine 5′-phosphate (430%, P &lt; 0.001) were increased.
4. The maximal activity of glutamine synthetase was increased (22–40%, P &lt; 0.001) in muscles of injured rats, whereas that of glutaminase was unchanged.
5. Hindlimb blood flow decreased by approximately 15% in injured rats, which was accompanied by an enhanced net release of glutamine (80%, P &lt; 0.001) and alanine (44%, P &lt; 0.001).
6. It is concluded that there is an enhanced rate of release of both glutamine and alanine from skeletal muscle of thermally injured rats. This may be due to changes in efflux and/or increased intracellular formation of glutamine and alanine.