bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Cardiovascular and Renal Responses to Short-Term Isolation in Brattleboro Rats
Authors: Gardiner S. M. , Bennett T. 
Published: August 2015

1. The effects of isolation on systolic blood pressure, heart rate and fluid and electrolyte balances were studied in rats with a congenital inability to synthesize vasopressin (Brattleboro strain) and in the normal parent strain (Long Evans).
2. There was no significant difference between the systolic blood pressures of Brattleboro rats and Long Evans rats while the animals were housed in groups, although the heart rates of the Brattleboro rats were significantly higher.
3. After S days of isolation in metabolism cages, systolic blood pressure was significantly increased in the Long Evans rats, but not in the Brattleboro rats.
4. Since there were no significant differences between the fluid and electrolyte balances of the two groups after 5 days of isolation, it is unlikely that the hypertension in the Long Evans rats was attributable to a renal action of vasopressin.
5. It is possible that vasopressin was involved in the development of isolation-induced hypertension by virtue of its pressor effects. Alternatively, the failure of Brattleboro rats to develop hypertension may have been due to some abnormality in these animals other than the lack of vasopressin.
A Micro-Method for the Study of Acid Secretory Function in Isolated Human Oxyntic Glands from Gastroscopic Biopsies
Authors: Fellenius E. , Elander B. , Wallmark B. , Haglund U. , Helander H. F. , Olbe L. 
Published: August 2015

1. A method has been developed whereby gastric glands can be obtained from biopsies taken from the human gastric mucosa.
2. Minced pieces of the mucosa incubated with collagenase (1 mg/ml) for 2 h yielded a fraction rich in isolated glands. Shorter incubation with collagenase produced larger chunks of tissue, whereas longer incubation resulted in many free cells which were less responsive to dibutyryl-cAMP and histamine; electron microscopy revealed the presence of mucous neck cells, parietal cells, zymogen cells and endocrine cells in the glands. Most of the cells appeared normal, but some of them were vacuolized. Acid secretion in these human glands was determined by the [14C]aminopyrine accumulation technique.
3. Owing to the limited amount of starting material, only a few determinations could be made from each set of biopsies by using the regular macro-method, which normally requires approximately 15 mg dry weight of glands per incubation. To overcome this problem a micro-method was developed which permitted the sample size to be scaled down to approximately 0.1 mg dry weight; in comparison with the previously used macro-method, the glands assayed by the micro-method seemed less sensitive to the method of shaking during incubation. In the micro-method the glands also seemed more responsive to secretagogues, i.e. histamine or dibutyryl-cAMP produced a two- to three-fold increase in [14C]aminopyrine accumulation. The histamine-induced secretion in human glands was effectively inhibited by the histamine H2-receptor antagonist, cimetidine, and that of dibutyryl-cAMP by the substituted benzimidazole, timoprazole. Cholinergic stimulation in the form of carbacholine led to a small and transient response.
4. Thus human gastric glands, as studied by this micro-method, seem to reveal normal secretory properties. The method may be used to study acid secretory function of gastric glands when human gastric material is restricted, as in the case of gastroscopic biopsies.
An Improved Method for the Determination of Potassium in Leucocytes
Authors: Schlebusch H. , Sorger M. , Höck A. , KrüCk F. 
Published: August 2015

1. in twenty normal subjects and five patients with disturbances of potassium balance, the potassium concentration in leucocytes was measured by a modified technique.
2. The precision of the method was three to four times greater than that of techniques previously described, with a coefficient of variation for duplicate analyses of 2.3%.
3. A comparison between intraleucocyte potassium concentration and total body potassium in five patients with pathological alterations in their potassium balance showed that intracellular potassium concentration may reflect the clinical state better than total body potassium.
Vertebral Bone Loss: An Unheeded Side Effect of Therapeutic Bed Rest
Authors: Krølner Bjørn , Toft Birte 
Published: August 2015

1. The skeletal effects of simple bed rest and re-ambulation were studied in a consecutive series of 34 patients (aged 18–60 years) hospitalized with low backache due to protrusion of a lumbar intervertebral disc. The bone mineral content of the second, third and fourth lumbar vertebrae was determined by dual-photon (153Gd) absorptiometry immediately after admission to the hospital, at the end of the bed-rest period (mean 27 days, range 11–61 days) and approximately 15 weeks later (range 11–24 weeks).
2. During recumbency a mean decrease in lumbar spine bone mineral content of 0.9% per week was observed.
3. Re-ambulation resulted in bone mineral gain, and restoration of lumbar spine bone mineral content was nearly complete after 4 months.
4. The findings suggest that the simple therapeutic bed-rest regimen leads to excessive vertebral bone loss. Recurrent bed-rest periods may predispose to spinal osteoporosis.
Central and Peripheral Nerve Conduction in Thyroid Dysfunction: The Influence of l-Thyroxine Therapy Compared with Warming upon the Conduction Abnormalities of Primary Hypothyroidism
Authors: Abbott R. J. , O'Malley B. P. , Barnett D. B. , Timson L. , Rosenthal F. D. 
Published: August 2015

1. The latencies of the visual evoked responses, indices of central nerve conduction, and peripheral nerve conduction were slowed in patients with primary hypothyroidism compared with controls.
2. in thyrotoxic patients, there was no change in the latencies of the visual evoked responses and peripheral nerve conduction compared with the control group.
3. The abnormalities seen in hypothyroidism were reversed by L-thyroxine therapy.
4. Warming untreated hypothyroid patients significantly improved both central and peripheral nerve conduction.
5. The conduction delay found in hypothyroidism is to a large extent dependent upon a subnormal body temperature.
Impairment of Cyclic AMP Response to Bovine Parathyroid Hormone in Patients on Chronic Lithium Therapy with Diminished Renal Urine-Concentrating Ability
Authors: Waller D. G. , Albano J. D. M. , Millar J. G. B. , Polak A. 
Published: August 2015

1. Urinary and plasma levels of adenosine 3′:5′-cyclic monophosphate (cyclic AMP) after an intravenous injection of bovine parathyroid hormone (PTH) were measured in 12 patients on long-term lithium treatment and in nine control subjects. The maximum urine osmolality (Umax.) after an intravenous injection of desamino-d-arginine vasopressin (DDAVP) was also measured.
2. in all the control subjects and six of the patients, the Umax. after DDAVP exceeded 700 mosmol/kg. The cyclic AMP responses in these two groups did not differ significantly.
3. in the remaining six patients whose Umax. did not reach 700 mosmol/kg, the cyclic AMP response to PTH was significantly less than that of the controls.
4. A strong correlation was demonstrated in the patients between the urinary cyclic AMP response after PTH and the maximum osmolality after the administration of DDAVP.
5. These observations are consistent with the hypothesis that reduced adenylate cyclase activity contributes to the development of nephrogenic diabetes insipidus in patients on long-term lithium treatment.
Formation of Hydroxyl Radicals from Hydrogen Peroxide and Iron Salts by Superoxide- and Ascorbate-Dependent Mechanisms: Relevance to the Pathology of Rheumatoid Disease
Authors: Rowley D. A. , Halliwell B. 
Published: August 2015

1. Superoxide and hydrogen peroxide are formed by activated phagocytes and react together in the presence of iron salts to form the hydroxyl radical, which attacks hyaluronic acid. Ascorbic acid also interacts with hydrogen peroxide and iron salts to form hydroxyl radical in a reaction independent of superoxide. Since iron salts, ascorbate and activated phagocytes are present in the rheumatoid joint, experiments were designed to see whether ascorbate-dependent or superoxide-dependent formation of hydroxyl radicals would be more important in vivo.
2. in the present study, addition of ascorbate to a superoxide-generating system at concentrations of 100 μmol/l provoked a superoxide-independent formation of hydroxyl radicals for a short period. Lower concentrations of ascorbate did not do this. It is therefore suggested that the superoxide-dependent reaction is probably more important.
3. It is further suggested that destruction of ascorbate by oxygen radicals formed by activated phagocytes accounts for the previously reported low concentrations of this compound in the serum and synovial fluid of rheumatoid patients.
Adrenalectomy and Glucocorticoid Administration In Vivo do Not Affect Production of 6-Oxoprostaglandin F1α by Rat Aortae
Authors: Rogers S. P. , Khalid B. A. K. , Funder J. W. , Larkins R. G. 
Published: August 2015

1. Rats were bilaterally adrenalectomized and treated for periods of up to 32 days with doses of dexamethasone equivalent to physiological and supraphysiological endogenous glucocorticoid secretion. Aortic production of 6-oxoprostaglandin F1α (6-oxo-PGF1α) was measured by radioimmunoassay of the supernatant fluid from rings of aorta incubated in vitro.
2. Up to 32 days after adrenalectomy, neither adrenalectomy nor dexamethasone (2 μg/day and 20 μg/day) influenced aortic 6-oxo-PGF1α production.
3. High doses of dexamethasone (60 μg/day for 6 days) in the presence or absence of mineralocorticoid (11-deoxycorticosterone, 600 μg/day) had no effect on aortic 6-oxo-PGF1α production.
4. in contrast to the lack of effect of dexamethasone administered in vivo, incubation of aortic discs for 5 h with dexamethasone (1 μmol/l) in vitro caused inhibition of aortic 6-oxo-PGF1α production to 23% of control levels.
5. Alteration in endogenous glucocorticoid secretion is unlikely to be involved in the physiological regulation of aortic 6-oxo-PGF1α, production.
Lack of Correlation between the Maximum Low-Density Lipoprotein (Ldl) Receptor Activity of Blood Lymphocytes and Plasma LDL Concentration in Normal Men
Authors: Cortese C. , Turner P. R. , Marenah C. B. , Sule U. , Price S. , Miller N. E. , Lewis B. 
Published: August 2015

1. Measurements were made of the maximal low-density lipoprotein (LDL) receptor activities of blood lymphocytes from 81 healthy men with a wide range of plasma LDL cholesterol concentrations (1.45-7.55 mmol/l).
2. Receptor activity was quantified by measuring the degradation of 125I-labelled LDL (10 μg of protein/ml) to trichloroacetic acid-soluble material during a 6 h incubation, after derepression of the lymphocytes for 72 h in lipoprotein-deficient medium.
3. No significant correlation existed between LDL receptor activity in vitro and plasma LDL cholesterol concentration in vivo (r = −0.08).
Uptake of l-Leucyl-l-Leucine and Glycylsarcosine by Hamster Jejunum in Vitro
Authors: Matthews D. M. , Burston D. 
Published: August 2015

1. Preliminary observations of the effects on intestinal transport of the lipophilic properties of the amino acid side chains of a series of neutral dipeptides showed that, contrary to expectation, l-valyl-l-valine and not l-leucyl-l-leucine was the most powerful inhibitor of uptake of the hydrolysis-resistant dipeptide glycylsarcosine by hamster jejunum in vitro.
2. Investigation of the kinetic characteristics of uptake of l-leucyl-l-leucine showed that Kt and Vmax. were lower than the corresponding values for l-valyl-l-valine, suggesting a higher apparent affinity for transport and a lower maximal velocity of transport. Ki for the inhibitory effect of l-leucyl-l-leucine on uptake of glycylsarcosine was less than one-half of the Kt for l-leucyl-l-leucine, so that inhibition was stronger than that expected from the apparent affinity for transport obtained from the kinetics of uptake of the inhibitor. In spite of this, l-leucyl-l-leucine was a much less powerful inhibitor of uptake of glycylsarcosine than was l-valyl-l-valine.
3. The results suggest that total uptake of l-leucyl-l-leucine at pH 5 is the result of at least two processes: uptake of intact peptide by one or more mechanisms, and also hydrolysis followed by uptake of free amino acid. At most concentrations, more than half the mediated uptake of l-leucyl-l-leucine was in the form of intact peptide.
4. The results of experiments on competition for uptake between dipeptides were unexpected. l-leucyl-l-leucine could inhibit mediated uptake of intact glycylsarcosine completely, but glycylsarcosine could not cause complete inhibition of mediated uptake of intact l-leucyl-l-leucine. Glycylsarcosine could, however, cause complete inhibition of mediated uptake of intact l-valyl-l-valine, which in turn could cause complete inhibition of mediated uptake of intact l-leucyl-l-leucine. The existence of more than one dipeptide uptake system in the small intestine seems probable.
Splenic Function in Sickle-Cell Diseases
Authors: Zago M. A. , Bottura C. 
Published: August 2015

1. Studies of splenic function were carried out on patients with sickle-cell diseases by the measurement of the clearance of autologous heat-damaged 99mTc-labelled erythrocytes from circulation and into the spleen, the spleen area by a scintillation scanning, the enumeration of pitted erythrocytes by direct-interference microscopy, and the percentage of irreversibly sickled cells (ISC) and of cells with Howell-Jolly bodies. All measurements were performed in seven HbS homozygotes, 10 patients with sickle cell β°-thalassaemia (S/β°-thalassaemia), three patients with sickle-cell disease (SC), four AS heterozygotes and 17 controls.
2. Three different patterns of splenic function were observed among the 20 patients with symptomatic sickle-cell diseases: six patients had enlarged hyperactive spleens, four had enlarged hypoactive spleens, and in 10 patients no splenic activity was detected.
3. The percentage of ISC was higher in sickle-cell anaemia than in S/β°-thalassaemia and very low in SC patients.
4. These results would suggest that the spleen goes through similar successive functional stages in the sickle-cell diseases, namely enlargement in the early years of life, which is followed by hypo-activity and finally atrophy. This evolution seems to be faster in sickle-cell anaemia than in S/β°-thalassaemia and SC disease.
The Effect of the Mammalian Neuropeptide, Gastrin-Releasing Peptide (GRP), on Gastrointestinal and Pancreatic Hormone Secretion in Man
Authors: Wood Susan M. , Jung Roland T. , Webster Joan D. , Ghatei Mohammed A. , Adrian Thomas E. , Yanaihara Noburu , Yanaihara Chizuko , Bloom Stephen R. 
Published: August 2015

1. Gastrin-releasing peptide, a newly isolated mammalian peptide similar in its structure and actions to the amphibian peptide, bombesin, has recently been localized to nerves in the brain, gut and pancreas. The present study investigates its effects on gut and pancreatic peptides in man.
2. Intravenous infusion of 0.7 and 2.9 pmol min−1 kg−1 produced significant elevation of plasma gastrin, cholecystokinin-like immuno- reactivity and neurotensin. It was found also to potentiate glucose-dependent insulin secretion.
3. Its specific location in nerve fibres in the proximal gut and pancreas and its selective effect on gastroenteropancreatic peptides may favour its role as a physiological regulatory neuropeptide.
The Immunological Assessment of α1-Antitrypsin with Reference to Its Function in Bronchial Secretions
Authors: Stockley R. A. , Afford S. C. 
Published: August 2015

1. The quantification of α1-antitrypsin (α1AT) by standard immunological techniques is altered by interaction of the protein with leucocyte elastase.
2. The results obtained for α1-antitrypsinleucocyte elastase mixtures in the presence of a functional excess of the inhibitor were relatively accurate for the first 6 h. However, continued incubation for more than 24 h led to a major over-estimation of the α1AT as the result of breakdown of the enzyme-inhibitor complex releasing a partially proteolysed form of the inhibitor.
3. In the presence of excess enzyme up to a twofold overestimation of α1AT occurred within 1 h and the degree of overestimation increased with time (up to threefold at 24 h). This was eventually associated with the presence of only a partially proteolysed form of α1AT (mol wt. ⋍ 50000).
4. Different results for each sample were obtained when different polyclonal antisera were used to quantify the α1AT.
5. Complete inactivation of α1AT by oxidation resulted in little change in the immunological quantification of the protein. However, further addition of H2O2 led to a progressive underestimation of the α1AT.
6. The effect of physicochemical alteration on the immunological quantification of α1AT by different antisera should be borne in mind for all studies assessing this protein in lung secretions.
Carbohydrate and Lipid Metabolism during Continuous Ambulatory Peritoneal Dialysis (CAPD): The Effect of a Single Dialysis Cycle
Authors: Heaton A. , Johnston D. G. , Burrin J. M. , Orskov H. , Ward M. K. , Alberti K. G. M. M. , Kerr D. N. S. 
Published: August 2015

1. The effect on hormonal status and intermediary metabolism of a single 6 h dialysis cycle at two different concentrations of dialysate glucose was investigated in six patients on continuous ambulatory peritoneal dialysis.
2. The basal blood glucose level was elevated by 0.5 mmol/l, associated with a threefold increase in basal serum insulin compared with seven normal controls. Blood glucose and serum insulin rose further during dialysis, particularly with hypertonic (215 mmol of glucose/l) dialysis fluid and levels remained high for 6 h after the onset.
3. Plasma glucagon concentrations were 2.7-fold increased and did not decrease to normal during dialysis.
4. Concentrations of the gluconeogenic precursors lactate and alanine were consistently raised, and levels of circulating non-esterified fatty acids and ketone bodies were lowered, particularly with hypertonic dialysis fluid.
5. The long-term effects of sustained hyper-insulinaemia, including suppression of lipolysis and ketogenesis, require further investigation.
Blood Pressure and Immunoglobulins
Authors: De Bruijn A. M. , Geers F. C. A. , Hylkema R. S. A. J. , Vermeeren R. , Hofman A. 
Published: August 2015

1. Serum concentrations of IgG and IgM were measured in 87 hypertensive and 87 normotensive subjects, matched for age and gender, and selected from the same general population.
2. No significant differences between these two groups were found, in contrast to some previous reports.
3. The reasons for this discrepancy are discussed.
The Effect of Local Temperature on the Response of An Extremity to Indirect Heating in Man
Authors: Allen J. A. , Finlay R. J. , Roddie I. C. 
Published: August 2015

1. Venous occlusion plethysmography was used to measure blood flow through the extremities of five normal subjects before and during exposure to a standard heat load with one extremity maintained at a cold (15°C) and the other at a neutral (35°C) temperature.
2. In the foot, local cold (15°C) delayed the onset and reduced by about 92% the vasodilatation during release of sympathetic vasoconstrictor tone caused by body heating.
3. Similar results were obtained in the hand exposed to cold (15°C) but the suppression of the reflex vasodilatation in response to body heating was about 66%.
4. This difference between the hand and foot did not appear to be related to the greater length of the foot since the distal half of the foot reacted like the total foot: local cooling suppressed the reflex vasodilatation by 88%.
5. The results suggest that sympathetic release tests should not be carried out in a laboratory with an environmental temperature as low as 15°C, especially when the circulation to the foot is under investigation.
Effect of Treatment on Skeletal Muscle Dysfunction in Hypothyroidism
Authors: Khaleeli A. A. , Edwards R. H. T. 
Published: August 2015

1. Abnormalities in skeletal muscle function were characterized in 19 hypothyroid subjects and the extent and time course of recovery in these abnormalities after treatment determined.
2. Slow muscle relaxation was observed on examination in 11 patients and 12 out of 16 patients had a reduced quadriceps maximum relaxation rate (MRR) and 11 out of 15 had a prolonged ankle jerk relaxation time (AJRT).
3. Measurements of quadriceps force revealed significant muscle weakness when comparison with 15 age matched healthy subjects was made (P&lt;0.001). This weakness was often not evident on clinical examination.
4. A raised plasma creatine kinase (CK) activity was characteristic.
5. With treatment the plasma CK activity and the AJRT rapidly became normal often long before the serum thyroid-stimulating hormone (TSH) was normal, but the quadriceps MRR was slower to recover. It was rarely normal before the serum TSH became normal. Weakness was slow to recover and seven patients remained weak at the end of the study despite being euthyroid for a mean period of 1 year, but strength increased modestly overall (P &lt; 0.01). The urinary creatinine/height index was unchanged, indicating that total muscle mass does not alter with therapy.
The Stability of Gastric Acid Secretion during Prolonged Pentagastrin Stimulation in Man
Authors: Petersen B. , Christiansen J. , Kirkegaard P. , Olsen P. Skov 
Published: August 2015

1. Prolonged stimulation with pentagastrin in doses of 100 and 500 ng h−1 kg−1 was performed in nine healthy subjects.
2. A plateau in gastric secretion was reached after 90 min with 100 ng h−1 kg−1 and 500 ng h−1 kg−1 resulted in a secretory plateau after 60 min.
3. When the plateau was reached the acid secretion rate was constant for the rest of the study, that is 4 h after beginning the pentagastrin infusion. Medians and interquartile ranges of acid output were 4.9 (3.7–5.2) and 8.1 (5.8–9.5) mmol of H+/30 min.
4. We conclude that no ‘fade’ of gastric acid secretion occurs during 4 h of submaximal pentagastrin stimulation in normal subjects, and that the time required for reaching a secretory plateau is dependent on the dose of pentagastrin.