On the nature of boundary-organized biomineralization (BOB).
Explore the source record for details and available documents.
Cells↗
Biomedical subjects
S Mann
Publications and source records attributed to S Mann.
Does placebo lower blood-pressure?
The effect of placebo on blood-pressure levels in 20 hypertensive patients was examined as part of a double-blind randomised controlled trial with indoramin. Blood-pressure was measured by both standard sphygmomanometry and ambulant intra-arterial monitoring. Blood-pressure reduction during the placebo phase, as measured by sphygmomanometry in the outpatient clinic, was highly significant for both systolic and diastolic pressures. In the same subjects, concomitant assessment by ambulatory monitoring showed no significant effect of placebo on intra-arterial pressure. After indoramin treatment blood-pressures measured in the clinic showed a mean reduction of 6/8 mm Hg whereas intra-arterial monitoring showed mean reductions of 18/13 mm Hg. The placebo response, therefore, appears to be an artifact of clinic blood-pressure measurement and its use as a control value in pharmacological trials may lead to serious underestimation of the efficacy of the active drug.
Adult↗
The effects of HDV-insulin on carbohydrate metabolism in Type 1 diabetic patients.
The aim of this study was to compare the metabolic effects of a single equimolar subcutaneous injection of hepatic directed vesicle-insulin (HDV-insulin) and regular insulin on glucose levels and intermediary metabolism during a 75-g oral glucose tolerance test (OGTT). Nine Type 1 diabetic patients underwent two experiments separated by 4 weeks. Each experimental protocol consisted of an identical evening meal followed by overnight euglycemic control achieved by a continuous low-dose insulin infusion. The next morning a subcutaneous injection (0.1 U/kg) of HDV-insulin or regular insulin was administered 30 min before a 75-g OGTT. The overnight basal insulin infusion was maintained unaltered throughout the 150-min OGTT. Plasma glucose, glucoregulatory hormones (insulin, glucagon, cortisol), and intermediary metabolites (lactate, alanine, glycerol, NEFA, beta-hydroxybutyrate) were measured to assess the metabolic effects of the two insulin preparations. Compared to regular insulin, an equivalent subcutaneous dose of HDV-insulin significantly lowered glucose levels during OGTT (mean reduction 2.2+/-0.4 mmol/l; P<.005). Plasma levels of insulin and glucagon were equivalent during both series of experiments. Blood lactate, glycerol and plasma NEFA levels were not different during OGTT indicating similar peripheral action of the insulins. beta-Hydroxybutyrate levels were significantly reduced (P<.05) following HDV-insulin supporting a preferential hepatic action of the preparation. We conclude that HDV-insulin can significantly lower plasma glucose excursions compared to an equivalent dose of regular insulin during an OGTT in Type 1 diabetic patients. The metabolic profile of equivalent peripheral insulin, glucagon and glycerol levels but reduced beta-hydroxybutyrate values support a hepatospecific effect of HDV-insulin.
Adult↗
A discussion of potential exposure metrics for use in epidemiological studies on human exposure to radiowaves from mobile phone base stations.
There is currently a high level of concern in many countries that exposure to radiowaves from mobile phone base stations may be hazardous to health. When investigating such suggested risks, epidemiologists need to define an exposure metric that can reliably discriminate between exposed and unexposed groups of people. We conducted a feasibility study to investigate if either short-term measurements of electric field strength, calculations of electric field strength, or distance from nearby mobile phone base stations could be used to develop a metric reflecting an individual's exposure to radiowaves. With electric field strengths in the range of 0.012-0.343 V/m, radiowaves from mobile phone base stations were found to give a material contribution to total exposure; however, stronger signals were frequently measured from other sources such as broadcast radio and television transmitters. Theoretical considerations and the measurements made during this work demonstrated that studies at the population level on suggested adverse effects of radiowaves from mobile phone base stations are not feasible since no valid metric for estimating historical exposures is currently available. The pace of radio infrastructure development is also such that today's measurements are unlikely to be good proxies for either past or future exposures. The complex propagation characteristics affecting the beams from base station antennas include shielding effects and multiple reflections from house walls and other buildings. These factors, combined with the presence of other environmental sources of radiowaves, cause distance from a base station to be a poor proxy for exposure to radiowaves indoors. It may be possible to adapt computer models developed by network providers to predict network coverage for epidemiological purposes; however, this has yet to be investigated. Furthermore, there is little evidence that presently justifies epidemiological studies being restricted to adverse effects of radiowaves from mobile phone base stations while neglecting radiowaves at other frequencies produced by different transmitters.
Electromagnetic Fields↗
[Emotional experience, expression and communication in musical improvization. A qualitative-quantitative single case study].
In this study the theory-conducted empirical procedure for analyzing active improvisatory music therapy of a single case will be described. The operationalization and tests for validation will be described. According to the aim of the study, the results show that the used method is appropriate to describe different and repetitive (emotional) patterns of improvisatory playing, which reflect the personal (emotional) and interpersonal pathology and healthy parts of the examined patient. With the aid of several tests the results of validating the macro-process will be discussed.
Expressed Emotion↗
Effects of oxprenolol on the intra-arterial blood pressure response to dynamic exercise in hypertensive men.
The intra-arterial blood pressure of 20 male patients with essential hypertension was continuously recorded during dynamic exercise. Graded exercise testing on a bicycle ergometer and a stair-climbing test were performed prior to and during treatment with oxprenolol. Acute oxprenolol therapy was associated with a reduction in heart rate but little reduction in blood pressure. Chronic treatment for 14.3 weeks with oxprenolol (mean daily dose, 344 mg) was associated with a substantial reduction of blood pressure at rest and at each level of bicycle exercise. A similar antihypertensive effect was demonstrated during stair climbing. The normal blood pressure response to exercise as assessed by the relative (percentage) increase in pressure above the pre-exercise level and the rate of increase in blood pressure (per unit of work), as well as exercise tolerance, were unchanged by chronic beta-blockade with oxprenolol.
Adult↗
Alpha-adrenoreceptor blockade with indoramin in hypertension.
We have evaluated the effects of indoramin, an alpha-adrenoreceptor blocking drug, used as sole therapy in a group of 27 patients with essential hypertension. Blood pressure and heart rate were measured continuously over prolonged ambulatory periods using an established invasive technique before and after six weeks of therapy. The protocol was randomised, double-blind, and with double-dummy placebo control. A standardised programme of physiological stress testing was also performed during each study. Placebo produced no appreciable change in the levels or patterns of blood pressure over 24-h periods, but indoramin produced a significant reduction, which was particularly marked during the night. Physiological testing did not reveal any postural hypotension, and the response to dynamic and isometric exercise was modified in level but not in degree of change. There were many unwanted effects, which may limit the clinical value of this drug.
Adrenergic alpha-Antagonists↗
The quantitation of arterial elasticity from Doppler flow measurements.
The pattern of phasic pressure and flow in an artery is related to the components of the impedance of that artery and hence to its compliance. Phasic patterns of velocity in peripheral arteries have been recorded by using continuous wave ultrasound Doppler flowmeters coupled to high-speed spectrum analysers; this has enabled display of the stored spectral ensembles as 'sonograms'. Simultaneous recordings at proximal and distal sites in each limb of a variety of subjects were made under standard resting conditions; characteristic patterns of change in the sonogram are recognized where gross abnormalities of arterial anatomy are present. A technique is under development whereby the mean values of velocity for each 7.4 ms time slice are derived, smoothed, and the pulse described by standard Fourier transform analysis. The change of the waveform occurring during passage through the relevant arterial segment is then described by comparing the amplitude/frequency and time-delay/frequency plots at proximal and distal sites. Although results are at present preliminary, changes relating to age and known vascular abnormality are becoming apparent. Further development is in progress to determine the significance of these findings.
Adult↗
Supine hypertension, blood pressure variability and circadian rhythm in autonomic failure: the role of ambulatory intra-arterial monitoring.
Blood pressure variation over 24 h was studied in twelve subjects with suspected or established autonomic failure using ambulatory intra-arterial monitoring. Three subjects who had been previously diagnosed as having orthostatic hypotension due to autonomic failure were found to have normal circulatory reflexes. A generally consistent circadian variation of blood pressure was seen in the other nine subjects, pressure rising gradually from its lowest point early in the morning to a peak during the early part of the night; this pattern was also found during bed rest in four subjects. Supine hypertension (an hourly mean blood pressure of greater than 170/90 mmHg) not suspected from sphygmomanometric readings was observed in four subjects, generally during the night. Heart rate variability was reduced in six subjects while short-term blood pressure variability was markedly increased.
Autonomic Nervous System Diseases↗
Nifedipine or verapamil as sole treatment of hypertension. An intraarterial study.
Intraarterial ambulatory blood pressures were recorded prior to and during therapy with two different calcium ion antagonists, nifedipine and verapamil, in two separate groups of patients. In the first group, nine patients were studied off therapy and following a minimum of 6 weeks of nifedipine treatment (dose range, 20 to 60 mg twice daily). A second group of 16 patients followed the identical protocol but were prescribed verapamil (120 to 160 mg, three times daily). During both studies, patients underwent standardized physiological tests including tilt, isometric handgrip, and dynamic bicycle exercise. Both verapamil and nifedipine caused a reduction in blood pressure over most of the 24 hours studied. Nifedipine did not affect heart rate whereas verapamil caused a reduction of approximately 10 bpm. Nifedipine and verapamil did not induce postural hypotension, and the absolute responses to dynamic and isometric exercise were reduced. These results show the efficacy of slow channel inhibitors in the management of essential hypertension.
Adult↗
The assessment of continuous ambulatory blood pressure records.
Explore the source record for details and available documents.
Ambulatory Care↗
Leukocyte esterase reagent strips for early detection of peritonitis in patients on peritoneal dialysis.
Explore the source record for details and available documents.
Carboxylic Ester Hydrolases↗