Effects of dynamic leg exercise on subcutaneous blood flow rate in the lower limb of man

Subcutaneous blood flow (SBF) was studied simultaneously in the upper arm at heart level and in the lower limb during positional changes and during leg exercise in seven healthy males. SBF was estimated by local clearance of ‘“Xenon registered by portable cadmium telluride detectors. Venous pressure was recorded directly on dorsum on the foot. Changinr the position from supine to head-up tilt, SBF decreased by 43 % (P < 0.01) at the arm level, 40% at the thigh (P < 0.01), 47% at the calf (P < 0.01) and decreased by 51 % at the ankle level (P < 0.01). Performing 20 heel-raisings per min in nearly erect posture, SBF increased by 96% at the thigh (P < 0.01), 25% at the calf (P > 0.1) and increased by 18% at the ankle level (P > 0.1). At 40 heel-raisings per min SBF increased by 99% at the thigh (P < 0.0 1), 121 % at the calf (P < 0.0 1), but only 44% at the ankle level (P > 0.1). During leg exercise subcutaneous vascular resistance was significantly increased at arm and ankle levels. In contrast, a vasodilatory response was noticed at the thigh and calf levels and seemed associated with a decrease in local venous pressure to below the trigger level of the sympathetic veno-arteriolar reflex mechanism. In conclusion, SBF in the lower limb of man was increased during exercise. The increase in SBF could only partly be ascribed to the concomitant increase in perfusion pressure. The local blood flow response seemed modified by changes in sympathetic nervous activity and metabolic rate.     

Evaluation of a Transcutaneous Oxygen and Carbon Dioxide Monitor in a Neonatal Intensive Care Department

Transcutaneous-Po₂; (tc-Po₂ (tc-Pco₂) at 44^oC and transcutaneous-Pco₂) at 38, 42, 43 and 44^oC were measured with a currently available monitoring system (TCM222, Radiometer, Copenhagen) in 64 newborn infants with severe respiratory insufficiency during the first five days of life. Tc-Pco₂ at all four temperatures correlated better with arterial blood-Pco₂ (aB-Pco₂)> than tc-Po₂ with aB-Po2. However, the sensitivity and specificity of tc-Po₂ and tc-Pco₂ were similar with regard to maintaining aB-Po₂, and aB-Pco₂ within specified limits. Tc-Pco₂ increased relatively with increasing electrode temperature by a factor which was similar to the anaerobic temperature coefficient of Po₂, in blood. The coefficient of variation of duplicate measurements was 10 % for tc-Po₂ and 5 % for tc-Pco₂. Electrode drift after an average of 3 hours patient monitoring was 2%±6% (1SD) for tc-Pco₂, and -3 %±6 % for tc-Pco₂- We conclude that tc-Po₂ and tc-Pco₂ are a valuable supplement to arterial blood gas measurements, but the variable correlation with arterial blood gas values and the electrode drifts which may occur, mean that they cannot fully replace arterial sampling.     

THE EFFECT OF DIURETICS IN LATE PREGNANCY ON THE NEWBORN INFANT

The changes in water and mineral metabolism in newborn infants born of mothers, who has been treated in late pregnancy with diuretics, was investigated. It was found, that all 6 parameters: the total body water, the extracellular water, the serum concentrations of sodium potassium and chloride and the osmolality all pointed in the direction that there was a slight salt and water depletion in the infants from the mothers, treated with diuretics. The biochemical observations were not clinically detectable.     

Pituitary-Thyroid Function and Thyrotropin,Prolactin and Growth Hormone Responses to TRH in Patients with Chronic Alcoholism

ABSTRACT Basal plasma concentrations of thyroxine (T₄), 3,3′,5-triiodothyronine (T₃), free T₄ index (TF₄I), free T₃ index (FT₃I) reverse T₃, 3,3′,5-triiodothyronine (rT₃), resin T₃ uptake (TR₃U), thyroxine-binding globulin (TBG), thyrotropin (TSH), prolactin (PRL) and growth hormone (GH) as well as thyrotropin releasing hormone (TRH) stimulated TSH, PRL and GH were investigated in 31 consecutive male patients (mean age 41 years) with chronic alcoholism. According to the histology of their liver biopsies the patients were divided into three groups: patients with normal livers, steatosis and cirrhosis. The control group consisted of 30 healthy males. The patients had abstained from alcohol for at least one week when studied, and they were on a nutritionally adequate diet. All had consumed a daily minimum of 52 g ethanol for at least 5 years. None of the patients had severe or decompensated liver disease. The patients had significantly reduced T₃ and rT₃ plasma levels compared to normals. Patients with cirrhosis of the liver had increased TBG and normal RT₃U levels, while those without cirrhosis had increased RT₃U and normal TBG levels. Plasma concentrations of basal as well as TRH-stimulated TSH and PRL were unchanged in alcoholic patients, whereas basal as well as stimulated GH levels were increased in cirrhotic alcoholics. It is concluded that alcohol per se influences T₃ levels, but not the part of the hypothalamic-pituitary axis studied, and that the binding proteins are mostly determined by the degree of liver disease.     

Palmitate and stearate binding to human serum albumin

Multiple binding equilibria of two apparently insoluble ligands, palmitate and stearate, to defatted human serum albumin were studied in a 66 mM sodium phosphate buffer (pH 7.4) at 37 °C, by determination of dialytic exchange rates of ligands among identical equilibrium solutions. The experimental data were analysed by a computerised curve fitting procedure using equilibrium equations for multiple binding of ligands, containing relative binding constants, valid whether the ligands are truly insoluble or are slightly soluble and irrespective of aggregation in aqueous solution. A best-fit set of relative binding constants was found, and subsequently 30 sets of acceptable constants for each set of data in order to evaluate the variation. The data were first fitted by the relative Scatchard's equation, then by the relative, stoichiometric equation. Scatchard's equation is deduced on the presumption that cooperativity is absent while the stoichiometric equation is valid even when cooperativity is present. It was found with palmitate as well as with stearate that the two equations fitted the data equally well, and it was concluded that the observations were compatible with absence of cooperativity. The relative Scatchard binding constants were converted to relative, stoichiometric constants and it was found that the variations of the latter were slight. © Munksgaard 1997.     

PSEUDOMONAS AERUGINOSA INFECTION IN CYSTIC FIBROSIS: Occurrence of Precipitating Antibodies against Pseudomonas Aeruginosa in Relation to the Concentration of Sixteen Serum Proteins and the Clinical and Radiographical Status of thi Lungs

ABSTRACT, Heiby, N., Jacobsen, L., Jergensen, B. A., Lykkegaard, E. and Weeke, B. (Statens Seruminstitut, Department of Clinical Microbiology at Blegdamshospitalet, the Paediatric Clinic TG with the Paediatric Clinic of Dronning Louises Børnehospital, the Radiologic Department TX, Rigshospitalet, and the Protein Laboratory, Untversity of Copenhagen, Copenhagen, Denmark). Pseudomonas aeruginosa infection in cystic fibrosis. Acta Paediatr Scand, 63: 843, 1974.—The significance of Pseudomonas aeruginosa infection in the respiratory tract of 9 cystic fibrosis patients have been studied by means of immunoelectrophoretical analysis of patients' sera for the number of precipitins against Pseudomonas aeruginosa and the concentrations of 16 serum proteins. In addition, the clinical and radiographical status of the lungs have been evaluated using 2 scoring systems. Precipitins against Pseudomonas aeruginosa were demonstrated in all sera, the maximum number in one serum was 22. The concentrations of 12 of the serum proteins were significantly changed compared with matched control persons. Notably IgG and IgA were elevated and the "acute phase proteins" were changed, the latter suggesting active tissue damage. The concentrations of 3 of the acute phase proteins, notably haptoglobin were correlated to the number of precipitins suggesting that the respiratory tract infection in patients with many precipitins is accompanied by more tissue damage than the infection in patients with few precipitins. The results indicate no protective value of the many precipitins on the tissue of the respiratory tract.     

Ionization of tyrosine residues in human serum albumin and in it complexes with bilirubin and laurate

Spectrophotometric titration of human serum albumin indicates that ionization of the 18 tyrosine residues takes place between pH 9 and 12.7. A Hill plot indicates that protons dissociate co-operatively from tyrosine residues, in pure albumin between pH 11.0 and 11.4 with a Hill coefficient 1.7, and in the bilirubin-albumin complex between pH 11.2 and 11.7 with a Hill coefficient 1.6. With a stopped-flow technique it is shown that about seven of the tyrosines ionize fast, with rate constants well above 10² s^?1, when pH is suddenly changed from near neutral to pH 11.76. Further residues ionize slowly, with rate constants around 10² s^?1 or less. The N-form of albumin (pH 6) contains one more fast ionizing tyrosine than the B-form of albumin (pH 10). Binding of bilirubin or laurate to the albumin molecule (molar ratio 1:1) transforms one to three of the fast ionizing tyrosines to slowly ionizing.