bluuebunny/crossref_metadata_2025_split huggingface dataset:
Increased levels of immunoreactive plasma renin substrate during infectious peritonitis in patients on continuous ambulatory peritoneal dialysis
Authors: Metsärinne Kaj , Fyhrquist Frej , Grönhagen-Riska Carola 
Published: August 2015

1. Renin substrate (RS) and certain serine protease inhibitors share structural homology. Previous studies have shown that RS may be an acute-phase protein.
2. This prospective study was carried out to monitor plasma RS and other components of the renin-angiotensin system and acute-phase proteins during infectious peritonitis in patients on continuous ambulatory peritoneal dialysis.
3. RS was measured by both an enzymatic assay and a direct radioimmunoassay. An enzymatic assay measures intact RS only, whereas a direct radioimmunoassay measures both intact RS, capable of releasing angiotensin I and des-(angiotensin I)-RS, the residue of RS after cleavage of angiotensin I.
4. RS determined by direct radioimmunoassay increased (P &lt; 0.001) during acute inflammation (peritonitis), whereas neither RS measured enzymatically nor plasma renin activity changed significantly.
5. Our observation points to RS being an acute-phase protein in man.
6. Serum angiotensin-converting enzyme was measured by both an enzymatic and an inhibitor-binding assay. Both assays showed decreased levels of angiotensin-converting enzyme during acute inflammation.
Muscle wasting in emphysema
Authors: Morrison W. L. , Gibson J. N. A. , Scrimgeour C. , Rennie M. J. 
Published: August 2015

1. We have investigated arteriovenous exchanges of tyrosine and 3-methylhistidine across leg tissue in the postabsorptive state as specific indicators of net protein balance and myofibrillar protein breakdown, respectively, in eight patients with emphysema and in 11 healthy controls. Whole-body protein turnover was measured using l-[1-13C]leucine.
2. Leg efflux of tyrosine was increased by 47% in emphysematous patients compared with normal control subjects, but 3-methylhistidine efflux was not significantly altered.
3. In emphysema, whole-body leucine flux was normal, whole-body leucine oxidation was increased, and whole-body protein synthesis was depressed.
4. These results indicate that the predominant mechanism of muscle wasting in emphysema is a fall in muscle protein synthesis, which is accompanied by an overall fall in whole-body protein turnover.
Effect of metoclopramide on dopamine-induced changes in renal function in healthy controls and in patients with renal disease
Authors: Smit A. J. , Meijer S. , Wesseling H. , Donker A. J. M. , Reitsma W. D. 
Published: August 2015

1. The effects of intravenous metoclopramide on baseline values and dopamine dose–response curves for renal haemodynamics and natriuresis were investigated in healthy volunteers and patients with renal disease.
2. Dopamine infusion alone, in doses ranging from 0.25 to 8 μg min−1 kg−1, resulted in a dose-dependent increase in effective renal plasma flow (ERPF) and glomerular filtration rate (GFR) with a fall in filtration fraction (FF) in eight hydrated healthy volunteers and, to a lesser degree, in 12 patients with renal disease. An increase in natriuresis (urinary excretion of sodium, UNa+V), fractional excretion of sodium (FENa+) and diuresis (urine flow rate, UV) was found in both groups for doses of 2 μg min−1 kg−1 and higher.
3. Metoclopramide infusion did not alter baseline values of GFR, ERPF or FF, but shifted the dopamine dose–response curve for ERPF and FF in the healthy volunteers. Metoclopramide induced a fall in UNa+V and FENa+ in both groups (fall in baseline FENa+ from 1.52 to 0.71 during metoclopramide in healthy volunteers and from 1.23 to 0.56 in patients; P &lt; 0.01) and blunted the natriuretic response to subsequent dopamine infusion. The fall in UNa+V during metoclopramide infusion showed a strong correlation with baseline GFR (r = −0.944). In the patients, the response for the fractional excretions of β2-microglobulin and γ-glutamyltransferase was comparable with that of FENa+.
4. Dopamine infusion induced a fall, and metoclopramide led to rise, in plasma aldosterone concentration.
5. We conclude that metoclopramide acts as a dopamine antagonist at the renal level in man. Endogenous dopamine secretion does not seem to have a role in maintaining ERPF or GFR in hydrated healthy volunteers or in patients with renal disease, but is important for mediating natriuresis. Dopamine-induced changes in natriuresis were not found to depend on changes in renal haemodynamics.
Decreased membrane fluidity of erythrocytes and cultured vascular smooth muscle cells in spontaneously hypertensive rats: An electron spin resonance study
Authors: Tsuda Kazushi , Tsuda Seiko , Minatogawa Yohsuke , Iwahashi Hideo , Kido Ryo , Masuyama Yoshiaki 
Published: August 2015

1. Membrane fluidity of erythrocytes and cultured vascular smooth muscle cells was studied in spontaneously hypertensive rats (SHR; Okamoto and Aoki strains) by means of an electron spin resonance (e.s.r.) and a spin-label technique.
2. The values of outer hyperfine splitting (2T) and of the order parameter (S) determined from e.s.r. spectra for a fatty acid spin-label agent (5-nitroxy stearate) were significantly higher in erythrocytes of SHR (4 and 10–13 weeks of age) than in those of age-matched Wistar–Kyoto rats (WKY). This finding suggests that the membrane fluidity of erythrocytes might be decreased in SHR.
3. The fluidity of cultured vascular smooth muscle cells obtained from 10-13-week-old SHR was also reduced compared with that from WKY.
4. These results suggest that the decreased membrane fluidity might be a genetically determined abnormality of the cell membranes in SHR.
Mechanisms of leucocyte sodium influx in essential hypertension
Authors: Ng L. L. , Harker M. , Abel E. D. 
Published: August 2015

1. Leucocyte Na+ influx in media containing 10 mmol/l Na+ was studied directly using a triple-isotope method for measuring initial 22Na uptake rates in 20 normal and 18 untreated hypertensive subjects. The effects of 1 mmol/l amiloride (a Na+-H+-antiport inhibitor) and 0.1 mmol/l bumetanide (a Na+, K+, Cl−-symport inhibitor) were also examined.
2. The total, amiloride-sensitive and bumetanide-sensitive influx rates were raised in hypertensive compared with normotensive subjects [median (range): total 0.63 (0.25–1.82) vs 0.40 (0.09–0.65) mmol min−1 l−1, P &lt; 0.002; amiloride-sensitive 0.43 (0.18–1.56) vs 0.26 (0.04–0.48) mmol min−1 l−1, P &lt; 0.002; bumetanide-sensitive 0.12 (−0.03 to 0.83) vs 0.02 (−0.25 to 0.21) mmol min−1 l−1, P &lt; 0.005].
3. We conclude that hypertensive patients have a raised leucocyte total Na+ influx when measured in media containing 10 mmol/l Na+ and that this is contributed mainly by amiloride-sensitive and bumetanide-sensitive Na+ influx mechanisms.
Aerosol deposition in the human lung: Effect of high-frequency oscillation on the deposition characteristics of an inhaled nebulized aerosol
Authors: Thomas Simon H. L. , Langford Jackie A. , George Robert J. D. , Geddes Duncan M. 
Published: August 2015

1. Oral high-frequency oscillation (OHFO) may have important effects on aerosol deposition in the lungs. In order to investigate these, a technique was devised to measure regional deposition rates of a nebulized radio-labelled aerosol in the lungs during normal tidal breathing.
2. The effect of three frequencies of OHFO on pulmonary aerosol deposition rate (PADR) in four normal subjects and five patients with chronic airways obstruction (CAO) were assessed using the technique.
3. In separate experiments employing three normal subjects, the effect of OHFO was studied on the deposition rate of aerosol on the oropharynx and delivery apparatus, and on the amount and characteristics of aerosol inhaled by the subjects.
4. Total PADR was significantly reduced by OHFO at 8 Hz and 16 Hz in the normal subjects, and by all three frequencies of OHFO in the CAO patients. In the normal subjects, the regional distribution of aerosol deposition was unchanged, but in the CAO patients a larger proportion of total aerosol deposition occurred in peripheral lung.
5. OHFO reduced the oropharyngeal aerosol deposition rate, increased the loss of aerosol to the atmosphere before inhalation, and increased the deposition of aerosol on the delivery apparatus. The end result was a reduction in the amount of aerosol inhaled, and in the particle sizes measured at the mouthpiece.
6. We conclude that OHFO reduces the amount of aerosol inhaled, but may improve peripheral deposition of inhaled aerosol in patients with CAO. This effect may be of value in the clinical administration of nebulized drugs.
Effect of protoporphyrin IX on ursodeoxycholate-induced hypercholeresis in the rat
Authors: Garcia-Marin J. J. , Redondo-Torres J. G. , Perez-Barriocanal F. , Berenson M. M. 
Published: August 2015

1. It is known that the perfusion of rat livers with solutions containing protoporphyrin IX induces a decrease in bile flow which is not due to inhibition of bile acid secretion but rather to decreased electrolyte transport into bile. By contrast, ursodeoxycholate induces hypercholeresis, partly due to a marked stimulation of biliary bicarbonate secretion. The aim of the present work was to investigate the effect of protoporphyrin IX on ursodeoxycholate-induced choleresis in anaesthetized male Wistar rats.
2. Protoporphyrin IX infusion at rates of 10, 20 and 40 μg min−1 100 g−1 body weight into the jugular vein induced a dose-dependent inhibitory effect on bile flow as well as on bile acid and electrolyte secretion. The lowest infused rate only induced slight and non-significant changes in spontaneous bile formation and functional variables such as glycaemia, packed cell volume, blood pH, Pco2, Po2 and bicarbonate concentration, and in hepatic carbonic anhydrase activity. It was thus considered as a subtoxic dose.
3. Sodium taurocholate was infused (0.5 μmol min−1 100 g−1 body weight) over the second hour of the lowest dose of protoporphyrin IX infusion. In these rats, no significant changes in bile flow or bile acid and electrolyte secretion were observed as compared with animals receiving sodium taurocholate plus saline solution.
4. Bile acid secretion induced by ursodeoxycholate infusion (1 μmol min−1 100 g−1 body weight) was similar both in rats receiving ursodeoxycholate plus saline solution and in animals infused with this bile acid over the second hour of the lowest dose of protoporphyrin IX infusion. However, bile flow and biliary bicarbonate secretion induced by ursodeoxycholate were markedly impaired (− 43% and − 56%, respectively) by protoporphyrin IX.
5. These results indicate that in the rat, in vivo, protoporphyrin IX impairs bile formation in a dose-dependent manner. They suggest that the mechanism(s) involved in ursodeoxycholate-induced bicarbonate secretion, and hence hypercholeresis, are particularly sensitive to the inhibitory effect of protoporphyrin IX.
Reproducibility of haemodynamic and plasma catecholamine responses to isometric exercise and mental arithmetic in normo- and hyper-tensive subjects
Authors: Lenders Jacques , Houben Harry , Van Valderen Rudolf , Willemsen Jacques , Thien Theo 
Published: August 2015

1. To determine the reproducibility of a mental arithmetic stress test and a handgrip exercise test, we studied the responses of blood pressure, heart rate, forearm blood flow and plasma catecholamines on two occasions, with an interval of at least 1 week, in 24 normotensive and 22 hypertensive subjects.
2. The se of a single observation of the percentage changes of blood pressure ranged from 3.9 to 9.3% in normotensive subjects and from 3.9 to 7.4% in hypertensive subjects in both tests. For heart rate, these values were 4.9–12.3% in the normotensive subjects and 4.8–5.7% in the hypertensive subjects. However, there was a wide individual scatter of these haemodynamic responses during both tests. The forearm blood flow, only measured during mental arithmetic, had an se of a single observation of 33.7%.
3. In 10 normotensive subjects the se of a single observation of the change in plasma noradrenaline was 0.16 nmol/l during handgrip exercise and 0.09 nmol/l during mental arithmetic. The corresponding values for plasma adrenaline were 0.04 and 0.05 nmol/l.
4. In conclusion, although both tests showed a rather low se of a single observation for the blood pressure and heart rate responses in normo- and hyper-tensive subjects, there was a considerable individual variability. If related to the mean forearm blood flow responses, the se of a single observation of the forearm blood flow response was of similar magnitude. The limited intra-individual reproducibility of both tests should be borne in mind when interpreting pharmacological intervention studies or studies evaluating sympathoadrenal reactivity in cardiovascular disorders.
Effect of potassium depletion on renal tubular function in the rat
Authors: Walter S. J. , Shore A. C. , Shirley D. G. 
Published: August 2015

1. In order to investigate the effects of K+ depletion on renal function, micropuncture studies were performed on anaesthetized rats which had been kept on a K+-deficient diet for 2 weeks; results were compared with those from control animals.
2. In the K+-depleted animals, values for total glomerular filtration rate and single-nephron filtration rate were significantly lower than in controls. Urine osmolality was also reduced; this was associated with reductions in the osmolality, Na+ concentration and K+ concentration of papillary interstitial fluid. No significant difference between urine and papillary osmolality was observed.
3. Fractional reabsorption by the proximal convoluted tubule was enhanced in the K+-depleted animals; end-proximal fluid delivery was markedly reduced.
4. Absolute, but not fractional, delivery of K+ to the beginning of the distal tubule was reduced in the K+-depleted animals. In contrast to observations in control rats, no net secretion of K+ into the distal tubule occurred and there was indirect evidence of K+ reabsorption in the collecting duct.
5. K+ depletion was associated with reductions in the delivery of Na+ and water to early and late regions of the distal tubule, whereas excretion rates of Na+ and water were unaffected.
6. It is suggested that the reduction in Na+ delivery to the loop of Henle (arising from the changes in filtration rate and proximal tubular reabsorption) might contribute to the reduced medullary osmotic concentration observed during K+ depletion. Reductions in fractional reabsorption of Na+ and water in the collecting duct might result from lowered plasma aldosterone levels and the reduced medullary osmolality.
Reversal of nerve damage in streptozotocin-diabetic rats by acute application of insulin in vitro
Authors: Burnstock Geoffrey , Mirsky Rhona , Belai Abebech 
Published: August 2015

1. Immunohistochemical, immunoblotting and release experiments were performed on ileum from control rats, from 8-week streptozotocin-diabetic rats and from diabetic rats after acute application of insulin in vitro.
2. There was an increase in vasoactive-intestinal-polypeptide-like and a decrease in calcitonin-gene-related-peptide-like immunoreactivity in the myenteric plexus of the diabetic rat ileum, although electrically evoked release of both peptides from enteric nerves was defective. Acute application of insulin in vitro reversed the defective release and changes in immunoreactivity of vasoactive intestinal polypeptide and calcitonin-gene-related peptide seen in the enteric nerves of streptozotocin-diabetic rat ileum.
3. In addition, using a monoclonal neurofilament antibody RT 97 that recognizes a phosphorylated neurofilament epitope present in normal enteric nerves, it was shown that this phosphorylated neurofilament epitope was absent in diabetic nerves, even though a polyclonal neurofilament antibody revealed that neurofilaments were present in both axons and cell bodies of the myenteric plexus of diabetic rat ileum. After only 2 h of insulin incubation in vitro, the phosphorylated neurofilament epitope was again present in the nerves.
4. It is suggested that the abnormal distribution of phosphorylated neurofilaments and defective storage and release of vasoactive intestinal polypeptide and calcitonin-gene-related peptide in the present study may be a more general feature of diabetes. The restoration of these abnormalities by continuous acute insulin application in vitro shown here suggests that the availability of a steady level of insulin might prevent some of the changes which occur in early stages of diabetes. If so, this could influence the use of insulin in the treatment of diabetes, particularly in view of the recent report that short-term continuous subcutaneous insulin infusion restores the function of the autonomic and peripheral nerves in type I diabetic patients [Krönert, K., Hülsen, J., Luft, D., Stetter, T. & Eggstein, M. (1987) Journal of Clinical Endocrinology and Metabolism, 64, 1219–1223].
Inter-relationship between urinary kallikrein-kinins and arginine vasopressin in man
Authors: Yamada K. , Hasunuma K. , Shiina T. , Ito K. , Tamura Y. , Yoshida S. 
Published: August 2015

1. Physiological saline solution was infused in nine normal subjects and six patients with central diabetes insipidus (DI). At 120 min after the start of infusion, arginine vasopressin (AVP) was injected intramuscularly. Urine was collected in 30 min fractions before and after AVP administration.
2. The urinary excretions of kallikrein-like activity (KAL-A) (S-2266 hydrolysis activity) and immunoreactive kinins (i-kinins) were significantly lower in patients with DI than in normal subjects before AVP administration, while there were no differences in plasma renin activity, plasma aldosterone concentration, creatinine clearance and blood pressure between the two groups, except for a marked water diuresis in patients with DI. The urinary excretion of KAL-A and i-kinins correlated positively with the urinary excretion of AVP.
3. AVP administration increased both plasma AVP and urinary excretion of AVP to similar levels in both groups. As a result, urine volume decreased to a greater degree in patients with DI than in normal subjects. In contrast, the urinary excretions of KAL-A and i-kinins were increased by AVP administration, with a greater response in normal subjects than in the patients with DI.
4. After overnight fasting, acute water loading was carried out orally for 15 min in six normal subjects. At 30 min plasma AVP was suppressed by water loading to almost the basal level found in patients with DI. Urinary excretions of KAL-A and i-kinins in the first 30 min fraction after loading were also suppressed to the basal level in patients with DI. Later, the urinary excretion of KAL-A increased together with the increase in urine flow. Urine volume and free water clearance markedly increased except in the first 30 min fraction, compared with the control period.
5. Thus it is suggested that AVP is one of the factors regulating the renal kallikrein-kinin system in man, although it seems likely that urine flow is still a major factor in urinary kallikrein-kinin excretion.
Transamination of methionine in humans
Authors: Blom Henk J. , Boers Godfried H. J. , van den Elzen Jacintha P. A. M. , Gahl William A. , Tangerman Albert 
Published: August 2015

1. This study was designed to investigate the transamination pathway of methionine in humans.
2. Evidence is provided that methanethiol and its metabolites are formed via transamination of methionine.
3. Gas-liquid chromatography was used to measure serum and urinary transamination metabolites of methionine: 2-keto-4-methylthiobutyrate, 3-methylthiopropionate and methanethiol, and the metabolites of methanethiol, dimethylsulphide, protein—S—S—CH3 (a mixed disulphide of blood proteins and methanethiol) and X—S—S—CH3 (a mixed disulphide of methanethiol and another thiol with an unknown component X).
4. Methionine and the transamination intermediates were measured in 10 normal subjects, in six normal subjects after L-methionine loading (0.1 g/kg body weight) and in a male patient with hepatic methionine adenosyltransferase (EC 2.5.1.6) deficiency.
5. In the patient with methionine adenosyltransferase deficiency, at least 20% of methionine was degraded via transamination. In normal subjects transamination of methionine did exist but was quantitatively not important in methionine catabolism, not even after methionine loading.
6. The results of this study might be of importance for future studies on the role of methanethiol in hepatic encephalopathy.
The renin gene in patients with malignant hypertension and raised plasma renin activity
Authors: Samani N. J. , Ruprai A. K. , Brammar W. J. , Swales J. D. 
Published: August 2015

1. We have examined the hypothesis that the raised plasma renin activity in patients with malignant hypertension without an underlying cause is the consequence of expression of a duplicate renin gene.
2. DNA extracted from leucocytes of patients with malignant hypertension and of normotensive controls was digested with the restriction endonuclease PstI and hybridized with a radioactively labelled human renin complementary DNA probe. As an internal control the DNA was concurrently hybridized with a human c-myc protooncogene probe.
3. The signals for each subject from the two probes were quantitatively compared by densitometry.
4. There was no evidence of duplication of the renin gene in the patients with malignant hypertension.
Relationship between leucocyte sodium content and high blood pressure during development and resolution of pre-eclampsia
Authors: Seon R. , Forrester T. 
Published: August 2015

1. One hundred and five primigravidae were followed sequentially at 4-weekly intervals starting at gestational week 31. They were seen again at 6 weeks post partum.
2. At each visit measurements were made of blood pressure as well as of leucocyte and erythrocyte sodium and potassium content.
3. Eighty-five subjects completed the study. Seven developed pre-eclampsia.
4. In both controls and patients who developed preeclampsia, leucocyte and erythrocyte sodium content increased with gestational age and fell post partum. These changes were of greater magnitude in the patients with pre-eclampsia. Cell potassium fell in both groups, but to a greater extent in patients with pre-eclampsia.
5. These changes in cell sodium paralleled those in blood pressure in both groups.
6. These data suggest that the excessive blood pressure changes in pre-eclampsia might be related to similar changes in cell sodium content.
Local pathological responses to slow-release recombinant interleukin-1, interleukin-2 and γ-interferon in the mouse and their relevance to chronic inflammatory disease
Authors: Dunn C. J. , Hardee M. M. , Gibbons A. J. , Staite N. D. , Richard K. A. 
Published: August 2015

1. The present study describes the pathological responses to local administration of recombinant cytokines in subcutaneously implanted slow-release ethylene vinyl acetate (EVA) co-polymer in mice.
2. EVA-recombinant human interleukin-1β (104 units) implants induced the formation of chronic granulomatous inflammatory tissue between 4 and 7 days after implantation, characterized by predominant macrophage infiltration, neovascularization and fibrosis which persisted up to 21 days after-implantation. EVA-recombinant human interleukin-1α (104–105 units) implants induced a qualitatively similar but less intense response.
3. In contrast, recombinant human interleukin-2 (102–104 units) implants resulted in early lymphocytic vasculitis (4 days) and the development of a predominantly lymphoid lesion comprised of lymphoblasts and significant mononuclear cell proliferation by 7 days.
4. EVA-recombinant γ-interferon (103–104 units) implants failed to elicit a significant tissue response; with the exception of multinucleate giant cell formation the characteristics of these lesions closely resembled the mild fibrotic responses observed for EVA-bovine serum albumin (0.5–12.5 mg) implants.
5. These observations suggest that continuous endogenous local release of interleukin-1 or interleukin-2 in vivo is sufficient for the development of specific pathological features characterizing chronic immuno-inflammatory diseases.