bluuebunny/crossref_metadata_2025 huggingface dataset:
Walking capacity of patients with intermittent claudication during chronic antihypertensive treatment with metoprolol and methyldopa
Authors: Lepäntalo Mauri , von Knorring Johan
Published: April 2008

Summary. In a placebo‐controlled double‐blind crossover trial, the effect of a 3‐week course of treatment with metoprolol (100–200 mg daily) and methyldopa (500–1000 mg daily) on walking capacity on a treadmill with increasing work load was studied in 14 hypertensive patients with intermittent claudication.

The walking capacity was not affected by the antihypertensive treatment.
Blood glucose concentration dependent ACTH and cortisol responses to prolonged exercise
Authors: Tabata Izumi , Atomi Yoriko , Miyashita Mitsumasa
Published: April 2008

Summary. The purpose of this study is to investigate responses of serum ACTH and cortisol concentration to low intensity prolonged exercise. In experiment 1, 10 subjects fasted for 12 h and performed bicycle exercise at 49·3%V̇O2max (±4·3%) until exhaustion or up to 3 h. During the early part of the exercise, serum ACTH and cortisol concentrations did not increase from the pre‐exercise values (ACTH: 44±5 μg/1, cortisol: 139±52 μg/1). Whilst the time to serum ACTH concentration increasing varied among the subjects (60·180 min), the increases of this hormone occurred for all subjects (175±85 ng/1, P<0·05) when blood glucose concentration decreased to a critical level of 3·3 mmol/1. At the end of the exercise, blood glucose concentration decreased to 2·60±0·21 mmol/1, and serum ACTH and cortisol concentrations increased to 313±159 μg/1 and 371±151 μg/1, respectively. In experiment 2, four subjects performed the same intensity exercise until exhaustion, and were then given 600 ml of 20 g glucose solution, and immediately afterwards, they were asked to repeat the same exercise. The subjects continued the exercise for between 30 to 90 min until again reaching exhaustion. During the second exercise, blood glucose concentration increased to the pre‐exercise value (2·72±0·58 to 4·00±0·22 mmol/1, P<0·05) and simultaneously, serum ACTH concentration decreased considerably (354±22 to 119±54 ng/1, P<0·05). The results of the present study suggest that serum ACTH and cortisol concentration during low intensity prolonged exercise may be dependent on blood glucose concentration.
The effectiveness of local injections of vasodilating agents to produce vasodilation in subcutaneous tissue in rabbits
Authors: Duncan H. J. , Faris I. B. , DeYoung N. J.
Published: April 2008

Summary. . The isotope washout method has been widely used to study characteristics of the microcirculation in localized vascular beds. Some of these studies have used local injections of vasodilating agents to maximally dilate the vascular bed. This study was undertaken to determine the agent most effective in producing this critical vasodilation.

A rabbit model was constructed that allowed the study of the subcutaneous blood flow by either 133Xe and 131I‐antipyrine washout. Dose‐response curves were constructed for five agents. The agents used and the doses that produced the maximum washout rate, were histamine (100 μg), verapamil (0–5 mg), prostaglandin El (6 μg), papaverine (5 mg) and nitroprusside (60 μg.) The five agents at these doses were compared with each other, and nitroprusside produced a greater washout rate than papaverine (P<0005), histamine (P<0–001) and verapamil (P<0–005). There was no difference between nitroprusside and prostaglandin El (P>0–01) The effect of three of the agents in producing tissue oedema was examined by comparing the washout rates values obtained with the two isotopes. Both nitroprusside and papaverine produced large oedema whereas histamine resulted in little oedema formation.

Nitroprusside, therefore, appears to be the most suitable vasodilating agent for use in studies which require maximum vasodilation of localized vascular beds.
The effect of physiological temperature changes on the galactose elimination capacity of the isolated perfused pig liver
Authors: Winkler K. , Keiding S. , Tønnesen K. , Tygstrup N.
Published: April 2008

Summary. The effect of temperature changes (36–40°C) on the liver function was studied in the isolated perfused pig liver. When compared with control studies no effect was observed on lactate, glucose, bile flow, ATP and energy charge, and the recovery after the changes in temperature was complete. The only significant changes observed regarded the hepatic oxygen uptake and galactose elimination capacity. The increase of 1°C resulted in an increase in galactose elimination of 6%, corresponding to a Q10 of 1·98 (SEM 0·12) with an energy of activation of 48 kJ/mol (SEM 4·7). Oxygen uptake was linearly related to galactose elimination (1·75 mol for 1 mole change in galactose elimination). These results indicate that circulatory changes are unimportant within physiological temperature changes. It is concluded that temperature effects on galactose elimination are too small to warrant a correction when used as a clinical test of quantitative liver function.
The difference in blood pressure between upper arm and finger during physical exercise
Authors: Nijboer J. A. , Dorlas J. C. , Lubbers J.
Published: April 2008

Summary. A new apparatus which measures the blood pressure in the finger continuously and yet not invasively was tested for its usefulness during exercise. It was compared with upper arm measurements in 23 volunteers during prolonged bicycle ergometry. Simultaneously, a pulse plethysmogram was recorded from another finger of the same arm, whereas in six additional volunteers Doppler measurements were carried out on the radial artery. The results show that finger systolic pressure ceased to rise at about 40% of maximal exercise; the difference with the continuously rising systolic pressure in the upper arm becoming significant at 140 W. At the same time the amplitude of the finger plethysmogram became significantly higher than its initial value, indicating distinct cutaneous vasodilation, whereas the volunteers also became hot and started to perspire. However, the radial artery ‘flow’, deduced from the Doppler measurements, did not change significantly during exercise. It increased sharply and markedly in the cooling down period. Simultaneously with this increase in flow, HR and both systolic blood pressures fell drastically whereas the plethysmography amplitude remained about stable at its raised level. The results fit in with the idea that a compromise is achieved between the need for muscle activity and the need for temperature regulation. It is concluded that the Finapres functions well during exercise, but that the systolic pressure in the finger is not representative for its more central counterpart during cutaneous vasodilation. It is argued that opening up of AVAs may contribute to this pressure effect.
Diet‐induced thermogenesis in patients with liver cirrhosis
Authors: Eriksson L. S. , Thörne A. , Wahren J.
Published: April 2008

Summary. Diet‐induced thermogenesis after ingestion of a mixed meal was investigated in eight patients with documented liver cirrhosis and in eight age‐ and sex‐matched healthy controls. Respiratory gas exchange was measured continuously for one hour in the basal state and for three hours after ingestion of a mixed liquid meal, consisting of 17% kJ protein, 28% kJ lipids and 55% kJ carbohydrates and dispensed to correspond to 60% of the individually computed energy expenditure. Arterial substrate and hormone concentrations were determined before and at timed intervals for three hours after the meal. Urine was collected for determination of nitrogen excretion.

The patients' oxygen uptake, energy expenditure and respiratory quotient were similar to those of the controls in the basal state. After the meal, pulmonary oxygen uptake and energy expenditure rose markedly in both groups during the first hour and were subsequently stable. The average increase in oxygen uptake above basal during the whole study period was 21·2 ± 1·8% and 22·3 ± 1·2% (NS) in patients and controls, respectively. The corresponding increase in energy expenditure was 24·8 ± 2·0% in the patients and 24·9 ± 1·4% in the controls (NS). The respiratory quotient was elevated throughout the postprandial period in both groups but the quotient was significantly higher in the patients (P<0·05–0·001), suggesting a greater proportion of carbohydrate oxidation.

The basal arterial concentrations of insulin and glucagon were significantly higher in the patients. After the meal the insulin level increased 10‐ to 20–fold in both groups. Glucose concentration rose significantly in both groups to a maximum of 8·82 ± 1·00 and 8·03 ± 0·95 mmol/l in patients and controls, respectively, at 60 min after the meal. This was accompanied by a fall in the levels of glycerol and ketone bodies in both groups, indicating decreased lipolysis.

It is concluded that both the basal energy expenditure and the thermogenic response to a mixed meal are similar in patients with liver cirrhosis and in healthy controls. The patients' carbohydrate oxidation rose to a greater extent after the meal, probably as a consequence of excessive increases in insulin concentration, demonstrating that insulin resistance in these patients may be compensated for by postprandial hyperinsulinaemia.
Local skin pressure and its effects on skin microcirculation as evaluated by laser—Doppler fluxmetry
Authors: Schubert V. , Fagrell B.
Published: April 2008

Summary. The effect of prolonged local pressure on the skin microcirculation was investigated in the regions of the sacrum and gluteus maximus muscle to determine the aetiology of pressure sores. Thirty normal subjects (15 female, 15 male) were investigated. The subjects were divided into three age groups: group 1, ≤ 35 years; group 2, 36–64 years; and group 3, ≥ 65 years. Local pressure was applied with a specially designed instrument according to the sequence 0→ 110→ 0→ 110→ 0→ mmHg. Skin blood cell flux (SBF) was measured with a laser–Doppler technique and the local skin temperature measured with a thermistor.

No significant differences were seen in SBF due to sex or age. However, differences between the two areas studied were observed. SBF was maximal over the sacrum at 12–50 mmHg (1.6–6.7 kPa) applied pressure. With further pressure increases, the SBF signal decreased successively, reaching minimum level at 110 mmHg (14.6 kPa), where it was approximately 43% below the initial value. The SBF in the gluteus region showed a more stable pattern, with a maximum SBF at 13–60 mmHg (1.7–8.0 kPa). At both locations, an increased SBF at zero pressure was seen when the pressure was decreased from 110 to 0 mmHg.

The skin temperature (n = 7) increased by 2.7°C (range 1.9–3.5°C) over the gluteus and by 1.3°C (range 0.8–2.5°C) over the sacrum. This increase was more rapid over the gluteus region. Concomitantly a temperature‐dependent increase of SBF could be seen.

It is concluded that a cause for the greater frequency of pressure sores over the sacrum than over the gluteus region is the comparatively poorer regulation of microvascular flow in this area.
ST changes in relation to heart rate during bicycle exercise in patients with coronary artery disease
Authors: Wohlfart B. , Pahlm O. , Sörnmo L. , Albrechtsson U. , Lárusdóttir H.
Published: April 2008

Summary. Exercise test on cycle ergometer and coronary angiography were performed on 190 patients with chest pain. Volunteers with a normal thallium scintigraphy (n= 47) served as controls. The load started at 20 W and increased at a rate of 10 W min‐1until exhaustion or symptoms. Conventional 12‐lead ECGs were recorded by means of computer before, during and after exercise. Minimum ST amplitude 60 ms after the STJ point (ST60) at end of work with a cut‐off level of ‐1·10 mm had a sensitivity of 69% (52/75) and a specificity of 89% (37/42) when individuals with a normal resting ECG were considered. ST80 and sum of ST60 in left ventricular leads had slightly lower values of sensitivity and specificity. Changes in ST60 during exercise discriminated less well between the groups. Final heart rate during exercise (>148 min‐1) had a sensitivity of 88% (53/60) and a specificity of 89% (42/47). The change in heart rate during exercise (>66min‐1) had a sensitivity of 50/60 (only patients without (β‐blockers were considered). The best discrimination was obtained by defining a test score (TS) according to the linear equation TS = 2·95‐0·023 × HRE‐0·301 × ST60 where a positive value indicates a positive test and a negative value a negative test. Sensitivity and specificity were 21/23 (91%) and 40/42 (95%), respectively. The test score was also calculated in those patients having significant coronary disease and an abnormal resting ECG (no bundle branch block, no β‐blockers) and this yielded a sensitivity of 30/34.
Effects of experimental potassium depletion on renal function and urinary prostanoid excretion in normal women during hypotonic polyuria
Authors: Agnoli G. C. , Borgatti R. , Cacciari M. , Garutti C. , Ikonomu E. , Lenzi P. , Marinelli M.
Published: April 2008

Summary. During hypotonic polyuria renal function studies by the clearance (cl.) method, and urinary PGE2, 6‐keto‐PGF1α and TxB2 determinations were performed on 14 healthy women in normal potassium balance (N) and 14 healthy women in sustained potassium depletion (KD) induced by low dietary potassium intake (≤ 10 mmol day‐1) and natriuretic treatment. By using different depletive patterns, two groups with estimated cumulative potassium deficits of 160 ± 43 mmol (KD1, n= 8) and 198 ± 22 mmol (KD2, n= 6), respectively, were obtained.

(1) In both the KD1 and KD2 groups as compared to normal potassium balance (N), plasma potassium concentration and urinary potassium excretion were significantly lower; plasma renin activity was significantly higher.

(2) Only in KD2 did significant changes appear in renal function and urinary prostanoid excretions. Besides a decrease in creatinine c1. and the urinary flow rate, an increase in fractional chloride excretion and a reduction in distal fractional chloride reabsorption were manifest. The plasma chloride concentration was reduced too. Urinary prostanoid excretions were significantly (6‐keto‐PGF1α, TxB2) or tendentially (PGE2) lower.

(3) Indomethacin treatment resulted in changes in mean arterial pressure (increase) and creatinine cl. (decrease) which were not significantly different in normal potassium balance and KD groups. Only in KD2 did the drug significantly reduce the fractional salt and water excretions and the fractional sodium and chloride deliveries to the diluting segments. However, indomethacin was unable to correct the inhibition of distal fractional chloride reabsorption. Therefore, the potassium depletion attained in the KD2 group was efficacious in depressing renal prostanoid synthesis. This fact, in the presence of high levels of angiotensin II, induced a reduction of the glomerular filtration rate thus contributing to renal ability to retain chloride and potassium.
Regional variations in nocturnal fluctuations in subcutaneous blood flow rate in the lower leg of man
Authors: Sindrup J. H. , Kastrup J. , Jørgensen B.
Published: April 2008

The purpose of the study was to investigate possible regional variations in recently discovered nocturnal fluctuations in subcutaneous blood flow rates. Approximately 90 min after going to sleep, a 100% blood flow rate increment, lasting about 100 min, has been demonstrated in the distal and medial aspect of the right lower leg of normal human subjects. In the present study subcutaneous adipose tissue blood flow rates were measured simultaneously in the right and left lower legs of 16 normal human subjects over 12–20 h ambulatory conditions. The 133Xe wash‐out technique, portable CdTe(Cl) detectors and a portable data storage unit were used. The tracer depots were applied on the medial aspects of the right lower leg and on the medial (series 1) and lateral (series 2) aspect of the left lower leg 10 cm proximal to the malleolar level by means of the epicutaneous, atraumatic labelling technique. A nocturnal hyperaemic response was demonstrated at both the medial and lateral aspect of the leg. As for the degree of hyperaemia and the absolute blood flow rates in the different phases, there were some deviations between the medial and the lateral locations. However, a highly significant positive correlation was observed in both series concerning the duration of the period from going to bed until the hyperaemia phase (P< 0·001). The mechanisms involved in the nightly subcutaneous hyperaemia are at present unknown. The sudden, synchronized increase in nocturnal subcutaneous blood flow points to a central nervous or humoral elicitation, although local metabolic factors might participate as well.
Adenosine infusion to patients with ischaemic heart disease may provoke left ventricular dysfunction detected by echocardiography
Authors: Edlund A. , Albertsson P. , Caidahl K. , Emanuelsson H. , Wallentin I.
Published: April 2008

Summary. Infusion of the endogenous vasodilator adenosine to patients with ischaemic heart disease (IHD) frequently provokes myocardial ischaemia, possibly caused by a coronary steal. The aim of this study was to detect the occurrence and incidence of disturbances in left ventricular (LV) wall motion and Doppler indices of altered LV function during infusion of adenosine.

Thirty‐seven patients (six female) aged 37–74 years with IHD, verified by coronary angiography, were given up to 200 μg kg‐1 min‐1 (mean 155 ± 5) adenosine i.v. for 18 ± 1 min. LV wall motion was monitored by two‐dimensional echocardiography (2D‐echo). Doppler spectral signal was obtained from the mitral blood flow.

All but six of the patients experienced angina pectoris of habitual character in connection with the adenosine infusion. Heart rate increased by 22 ± 1 beats min‐1, systolic blood pressure was unchanged, but diastolic blood pressure decreased slightly. 2D‐echo revealed severe regional LV wall motion disturbances already in the basal state in 17 patients. During infusion of adenosine, these abnormalities were aggravated and disturbances also occurred in another 15 patients. Thus, adenosine increased the sensitivity for IHD in this selected material from 49 to 89%. In all, the mean index of wall motion abnormalities increased from 5·1 ± 1·1 to 10·1 ± 1·4 (P< 0·001). The diastolic LV filling characteristics, as evaluated by the Doppler A/E ratios, were of limited value for determination of IHD grade.

It is concluded that infusion of adenosine to patients with IHD frequently elicits myocardial ischaemia with disturbances in LV function, and offers an alternative to exercise for stress echocardiography.
Effects of experimental potassium depletion on renal function and urinary prostanoid excretion in normal women during moderate anti‐diuresis
Authors: Agnoli G. C. , Borgatti R. , Cacciari M. , Ikonomu E. , Lenzi P. , Marinelli M.
Published: April 2008

Summary. The hypothesis that potassium depletion (KD) might play a role in stimulating the renal synthesis of prostanoids, and that these materials can contribute to hypokalaemic renal dysfunction, has been tested. Healthy women were studied either in normal potassium balance (N, n= 14), or in experimental KD. KD was induced by low dietary potassium intake (10 mmol day‐1) and natriuretic treatment, associated with replacement of net NaCl and water loss. By using different depletive patterns, two groups with estimated cumulative potassium deficits of 160 ± 43 mmol (KD1, n= 8) and 198±22 mmol (KD2, n= 6), respectively, were obtained. Renal function by the clearance (cl.) method and urinary PGE2, 6‐keto‐PGFlä, TxB2 concentrations by the RIA method were measured during hypotonic polyuria (oral water load) and subsequent moderate antidiuresis induced by the infusion of low‐dose lysine‐8‐vasopressin (LVP). Compared to the N group, only in the KD2 group do glomerular and tubular dysfunctions typical of hypokalaemia and reduced prostanoid excretions (significant for 6‐keto‐PGFlä and TxB2 but not for PGE2) appear during polyuria besides the significant reductions of plasma potassium concentration, urinary potassium excretion and the significant increase in plasma renin activity. During LVP infusion the urinary prostanoid excretions were all significantly lower in absence of significant differences in urinary flow rate. Concerning its renal effects, LVP lost its ability to reduce the creatinine cl., while expressing a trend towards reduction in fractional chloride excretion. Indomethacin pretreatment restored the LVP effect on creatinine cl. and increased the antichloruretic LVP effect (although not significantly). To the extent that urinary prostanoid excretions reflect their intrarenal synthesis, our data demonstrate that KD inhibits this biosynthesis. A depressed production of prostanoids endowed with vasodilating and chloruretic activity probably played a role in attenuating the renal vascular hyporeactivity and the urinary chloride dispersion induced by KD.
Reference values for bicycle exercise tests in patients with various degrees of ischaemic heart disease
Authors: Frandsen F. , Andersen C. , Larsen H. C. , OxhØj H.
Published: April 2008

Summary. This investigation was carried out in an effort to analyze the influence of various degrees of ischaemic heart disease (IHD) on cardiovascular and physical performance. Assessment of the severity of IHD was based on observations obtained routinely during exercise tests (ST segment response and systolic blood pressure response). The study group included 926 subjects with known or suspected IHD, who were referred for an exercise testing; 268 females, mean age 54 years (range 19–89 years), and 658 males, mean age 52 years (range 16–88 years).

We found that increasing IHD severity was associated with significant reductions of cardiovascular performance. The mean maximum work‐load (MWL) was lower in females than in males, and MWL as well as mean maximum heart rate (MHR) and mean maximum change in systolic blood pressure (M Δ SBP) decreased with increasing IHD and age.

The present results may be used to assess the cardiovascular response to exercise in patients with IHD so that altered responses due to causes other than IHD may be identified. Furthermore the result may prove useful in the adjustment of rate responsive pacemakes (RRP) in patients with IHD.
Indirect pathway of liver glycogen synthesis in humans is predominant and independent of beta‐adrenergic mechanisms
Authors: Napoli R. , Capaldo B. , Picardi A. , Piscione F. , Bigazzi M. Capelli , D'Ascia C. , Sacca L.
Published: April 2008

Summary. The relative contribution of the direct and indirect pathways to liver glycogen formation was assessed in humans by using a combined tracer‐hepatic vein catheterization technique. An oral glucose load (75 g) labelled with 1‐14C‐glucose was administered to five subjects (control group) and 4.5 h later hepatic glycogen was flushed with glucagon and analysed to determine the randomization of 14C. The specific activity (SA) of the glycogen derived glucose (1‐14C‐glucose SA+recycled 14C‐glucose SA) was 61 ± 7% of the mean blood glucose SA of the interval 0–180 min after the oral glucose load. The relative values due to 1‐14C‐glucose and recycled 14C‐glucose were 33 ± 7 and 28 ± 3%, respectively. The data indicate that the indirect pathway of glycogen formation is not only active in humans but contributes substantially (at least 50%) to liver glycogen formation. In order to investigate whether the basal adrenergic tone plays a role in the maintenance of the indirect pathway, the same protocol was also performed in a second group of subjects (n= 5) who received propranolol before the oral glucose load (propranolol group). The SA of the glycogen‐derived glucose was considerably smaller than that of the control group (18 ±5 vs. 61 ± 7%, P< 0.001), suggesting lesser glycogen formation. However, the ratio of 1‐14C to recycled‐14C in the glucose molecule was similar in the control (1.3 ±0.4) and propranol group (1.9 ± 1.2). We conclude that the basal adrenergic tone does not play any role in the operation of the indirect pathway of liver glycogen synthesis.
No effect of carbohydrate feeding on glycogen synthase in human muscle during exercise
Authors: Yan Z. , Spencer M. K. , Katz A.
Published: April 2008

Summary. The effect of carbohydrate (CHO) feedings on exercise‐mediated changes in glycogen synthase fractional (GSF) activity has been investigated. Subjects cycled at ‐70% of maximal oxygen uptake on two occasions: the first to fatigue (135±17 min; meanæ) (control, CON), and the second at the same workload and duration as the first, but with the addition of frequent ingestion of CHO during exercise (0.27 g kg‐1 body weight every 15 min). Biopsies were taken from the quadriceps femoris muscle before and immediately after exercise. Plasma glucose and insulin decreased during CON exercise, but remained elevated throughout CHO exercise (end of exercise: glucose = 4.4±0.2 mM CON vs. 5.8±0.2 CHO, P < 0.01; insulin = 9±l mU ml‐1 CON vs. 19±3 CHO, P < 0.05). Glycogen decreased to ‐ 10% of the basal value during CON and to ‐20% during CHO, and there was no significant difference in net glycogenosis between treatments. GSF activity averaged 0.25±0.03 and 0.22±0.05 at rest, and increased to 0.51 ±0.08 and 0.48±0.09 after exercise in CON and CHO, respectively (P > 0.05 between treatments). It is concluded that under the present conditions CHO feedings do not alter the exercise‐mediated changes in GSF activity. The increase in GSF during exercise is attributed at least in part to the decrease in muscle glycogen (which increases the suitability of GS as substrate for GS phosphatase).
Plasma cholesterol ester transfer protein and distribution of cell cholesterol among plasma lipoproteins in vitro in distance runners and sedentary men
Authors: Sutherland W. H. F. , Stapely S. A. , Robertson M. C. , Nye E. R.
Published: April 2008

Summary. Plasma cholesteryl ester transfer protein (CETP) activity and distribution of red blood cell (RBC) cholesterol among plasma lipoproteins during incubation of blood were determined in 14 distance runners and 10 sedentary men. Mean plasma CETP activity was similar in the runners (31% 10 μl‐1 18 h‐1) and the sedentary men (32% 10 μl‐1 18 h‐1). There was significantly (P<0.05) greater accumulation of cell cholesterol in the HDL fraction (runners: 0.33 mmol 1‐‐1; sedentary men: 0.23 mmol l‐1) which comprised a significantly (P<0.05) larger proportion of the total amount of cell cholesterol lost to plasma (runners: 89%; sedentary men: 64%) in incubated blood from the runners. The results of this study suggest that in distance runners, high HDL concentrations are not accompanied by reduced plasma CETP levels but in conjunction with low triglyceride‐rich lipoprotein levels in plasma, may promote preferential distribution of cell cholesterol into the ‘antiatherogenic’ HDL fraction.
Loss of the nocturnal dip and increased variability of blood pressure in normotensive patients with noninsulin‐dependent diabetes mellitus
Authors: Hassan M. O. , Shafie O. T. Al , Johnston W. J.
Published: April 2008

Summary. Eleven normotensive diabetics with noninsulin‐dependent diabetes mellitus (NIDDM) (mean age 52.5 SD 8.2 years) and 11 controls (mean age 47.4 SD 8.9 years) had their ambulatory blood pressure and heart rate recorded non‐invasively by the Oxford Medilog System in standard hospital conditions.

The results were averaged as hourly means of systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial blood pressure (MAP), and heart rate (HR) for the 24‐h period and similarly for the ‘awake’ period (14.16 h) and the ‘asleep’ period (8–10 h).

Hourly means for diabetics and controls showed no differences in blood pressure and heart rate over the 24 h. During sleep, control subjects showed a significant drop in SBP (P < 0.001), DBP (P < 0.001), MAP (P < 0.001) and HR (P < 0.001). However, this nocturnal dip in blood pressure could not be demonstrated in the diabetic group. Blood pressure variability was significantly increased in diabetics compared to controls during waking hours (P < 0.01).

These results indicate that in noninsulin‐dependent diabetics during sleep there is loss of the nocturnal dip of BP seen in normal subjects, and they have increased BP variability. These may be contributing factors to the development of hypertension and the accelerated target organ damage (TOD) seen in diabetes.,
Increased urinary excretion of a major thromboxane metabolite in early alcohol withdrawal
Authors: Neiman J. , Nowak J. , Benthin G. , Numminen H. , Hillbom M.
Published: April 2008

Summary. Urinary excretion of 2, 3‐dinor‐thromboxane B2 as a marker of in vivo thromboxane A2 (TXA2) biosynthesis was measured in six alcoholics 1 and 14 days after the cessation of heavy drinking using gas chromatography/mass spectrometry. Six non‐alcoholic healthy volunteers served as controls. One day after alcohol withdrawal the excretion of the dinor metabolite was significantly higher (P<0–01) in the alcoholics (408 ± 42 pg mg‐1 creatinine) than in the controls (180 ± 30 pg mg‐1 creatinine) and was accompanied by a significantly reduced platelet count (103–0 ± 20–2×1109 1‐1 vs. 194–0 ± 13–9×109 1‐1 in controls; P<001). The metabolite excretion fell then significantly (P<0–05) to 245 ± 53 pg mg‐1 creatinine 14 days after alcohol withdrawal and this was paralleled by an increase in platelet count to 453–5 ± 72–0×109 1‐1 (P<0–05). The present results support the hypothesis that TX‐A2 biosynthesis is increased in early alcohol withdrawal and strongly suggest platelets as a cellular origin of the increased TXA2 formation.
Effects of digitalis, anti‐anginal drugs and arterial hypertension on the relationships between exercise ECG and angiocardiographic variables and on the diagnostic accuracy of exercise ECG in patients with coronary heart disease
Authors: Backman C. , Jacobsson K.‐A. , Linderholm H. , Osterman G.
Published: April 2008

Summary. We have previously found a statistically significant correlation between some exercise ECG variables and angiocardiographic scores used to evaluate the extent and type of coronary heart disease (CHD). In the present study we examined the effects of digitalis, ^‐adrenergic blockers, slow release nitrates, calcium channel blockers, presence of arterial hypertension (AHT), and angiocardiographic changes on the exercise ECG variables. The effects of drugs and AHT were small as compared to the effects of the angiocardiographically detected pathological changes caused by the CHD. Sensitivity and specificity of the exercise ECG ST criteria in identifying patients with an angiocardiographic criterion indicating coronary insufficiency were not much different in the whole group and in the subsets with AHT or medication with digitalis and anti‐anginal drugs.
Noninvasive study of left ventricular function and systemic haemodynamics during dipyridamole echocardiography stress test
Authors: Aakhus S. , Bjørnstad K. , Hatle L.
Published: April 2008

Summary. Left ventricular function and systemic haemodynamics were noninvasively assessed during cardiac stress testing with dipyridamole (0–84 mg kg‐1 i.v.) in 10 subjects (44–61 years) with normal coronary arteries (group 1), and in 14 patients (46–77 years) with coronary artery disease either without (group 2, n= 6) or with (group 3, n= 8) echocardiographic evidence for myocardial ischaemia during test. Left ventricular wall motion and dimensions, and aortic root pressure and flow were obtained by Doppler echocardiography combined with an externally traced subclavian artery pulse calibrated with brachial artery pressures. Peripheral arterial resistance, total arterial compliance, and aortic characteristic impedance were estimated from aortic root pressure and flow, by use of a three‐element windkessel model of the systemic circulation. Left ventricular ejection fraction improved from baseline to peak stress in group 1 (mean ± SD: 62 ± 6% vs. 65 ± 6%, P= 0–05), whereas it was not significantly changed in group 2 (58 ± 10% vs. 56 ± 6%) and decreased in group 3 (53 ± 10% vs. 43 ± 10%, P<0–05). Otherwise, the haemodynamic response was similar in the three groups: heart rate and cardiac index increased by at least 30% and 37%, respectively, whereas stroke index and arterial pressures were maintained at or slightly above baseline. Peripheral resistance decreased by at least 22%, and total arterial compliance and aortic characteristic impedance were not significantly altered during test. The worsening of wall motion abnormality at peak stress in group 3 was not significantly related to the change in systemic haemodynamics. Thus, dipyridamole acted predominantly on the arterioles without significantly influencing the large systemic arteries. Myocardial ischaemia during test impaired regional and global left ventricular function, but did not influence the systemic haemodynamic response.
Fatty acid exercise scintigraphy after percutaneous transluminal coronary angioplasty
Authors: Walamies M. , Niemelä K. , Turjanmaa V. , Koskinen M.
Published: April 2008

Summary. We performed a sequential fatty acid exercise‐rest scintigraphy in 18 patients with an initially successful percutaneous transluminal coronary angioplasty (PTCA) to study the concordance of trends in symptoms, exercise tolerance and myocardial metabolism. Eleven patients stopped the exercise because of angina pectoris in the preoperative test; 2 days after PTCA this number decreased to two, but again increased to eight 3 months later. Exercise time (9–7 ± 0–6 min, mean ± SEM) and maximum exercise heart rate (128 ± 4 beats min‐1) were at least as good immediately after the operation as originally (8–8 ± 0–6 min and 121 ± 4 beats min‐1, respectively). After 3 months both parameters were significantly (P<0–05) better (10–3 ± 0–6 min and 136 ± 4 beats min‐1, respectively) than originally.

Some relative improvement in washout was noticed in 61% 2 days and in 56% of cases 3 months after PTCA. Fatty acid exercise uptake was more homogeneous in 72% of cases immediately after angioplasty and in 44% 3 months later. The trend in fatty acid uptake, exercise characteristics, and also in symptoms was most favourable among the eight patients with a dilatated left anterior descending coronary artery.

Although the gamma camera technique possibly underestimated the effects of angioplasty, the impaired fatty acid metabolism could be linked with persistent symptoms after the operation. We conclude that most patients can safely participate in a symptom‐limited (maximal) ergometry test already 2 days after PTCA, and that postoperatively myocardial perfusion and metabolism improve rapidly. However, this advantage is eventually lost to some degree, even if exercise tolerance continues to improve.
Calculation of renal extraction during high diuresis and low renal plasma flow conditions
Authors: Andersson L.‐G. , Bratteby L.‐E. , Ekroth R. , Wesslén Ö. , Hallhagen S.
Published: April 2008

Summary. The renal fractional extraction (Ex) is a parameter describing the ability of the kidneys to remove a substance x from the circulating plasma. Ex is calculated often as the ratio between the arteriovenous concentration difference and the arterial concentration. This method simplifies the calculations but it is associated with an underestimation of Ex. In the study described here, a theoretical analysis of the error is made, with a graphical presentation of its magnitude in different diuresis/renal plasma flow (RPF) ratios and at different levels of Ex. The error was analysed also in a clinical situation where the renal extraction of PAH (EPAH) and EDTA (EEDTA) were determined in six patients during different stages of cardiac surgery. The underestimation of EPAH was seldom more than 4%, while EEDXA was underestimated often with more than 20%.

It is concluded that the simplified formula is accurate when calculating the renal extraction for substances like PAH, with a normally high extraction, even if the diure‐sis/RPF ratio is high. For substances with low extractions, e.g. filtration markers, in some clinical and experimental situations it is necessary to take the renal plasma flows into consideration or to arrange for low urine production to avoid significant errors.,
Response of plasma neuropeptide Y and noradrenaline to dynamic exercise and ramipril treatment in patients with congestive heart failure
Authors: Ullman B. , Lindvall K. , Lundberg J. M. , Sigurdsson A. , Swedberg K.
Published: April 2008

Summary. Forty‐two patients with congestive heart failure were studied in order to clarify whether the plasma level of neuropeptide Y‐like immunoreactivity (NPY‐LI) rises in parallel with plasma noradrenaline (NA) during physical exercise in congestive heart failure (CHF). All patients were studied in a randomized placebo‐controlled trial with the ACE‐inhibitor ramipril during 12 weeks to determine whether ACE‐inhibition alters the response of plasma NPY‐LI to exercise. The patients were treated with diuretics and had stable congestive heart failure (NYHA classes II‐III). Plasma NPY‐LI was 50 5 pmol 1‐1 (mean standard error of the mean) at rest and 60 6 pmol l‐1 at the end of exercise at baseline (P < 0–01). The corresponding values for plasma NA were 2–8 0‐2nmoll‐1 and 15‐3 l‐2nmoll‐1(P < 0–001). Before ACE‐inhibition, there was a correlation between high NPY‐LI and NA values after exercise. After treatment with ramipril or placebo for 12 weeks, there was no difference in plasma NPY‐LI and NA at rest or after exercise between the two treatment groups. The maximal exercise time was unchanged.

It is concluded that plasma NPY‐LI and NA were elevated at rest in CHF. The additional rise of plasma NPY‐LI and NA after exercise was attenuated in CHF compared to healthy individuals. ACE‐inhibition with ramipril did not alter plasma NPY‐LI or NA at rest or after exercise compared to placebo.
Inhibitory effects of neuropeptide Y on splanchnic glycogenosis and renin release in humans
Authors: Ahlborg G. , Lundberg J. M.
Published: April 2008

Summary. Neuropeptide Y (NPY) is stored in sympathetic nerves and NPY levels increase several times during exercise. NPY administration during prolonged exercise causes reduced splanchnic glucose production. To elucidate the effects of NPY on adrenaline (Adr)‐stimulated splanchnic glycogenolysis these substances were infused to seven healthy subjects in the post‐absorptive state. Blood samples were drawn from an arterial and a central hepatic vein catheter for determination of splanchnic blood flow, exchanges of metabolites and arterial levels of NPY, catecholamines, insulin, glucagon and renin in the basal state and during 20 min Adr infusion (0–1‐0‐3 nmol kg‐1 min‐1). After basal values were reached a 60 min NPY infusion was initiated. At 40 min of NPY infusion the Adr infusion was repeated. Adr alone increased splanchnic blood flow (41%, P < 0–01), arterial glucose concentration (29%, P < 0–001) and splanchnic glucose production (102%, P < 0–01). During the NPY infusion both splanchnic blood flow and arterial glucose fell (P < 0–05). Although the combined NPY and Adr infusion caused the same proportional increases in splanchnic blood flow, arterial glucose and splanchnic glucose production as with Adr alone the absolute values were lower (all P < 0–05). Arterial insulin as well as Adr and noradrenaline increased with the combined NPY‐and Adr infusion as with Adr alone. Arterial plasma renin activity was 12% lower with the combined NPY and Adr‐infusion compared to Adr infusion alone.

These results indicate further an inhibitory effect of NPY on splanchnic glycogenolysis and suggest that NPY inhibits Adr‐stimulated renin release.,
Effects of angiotensin‐converting enzyme inhibition on renal dysfunction induced by moderate potassium depletion in healthy women
Authors: Agnoli G. C. , Borgatti R. , Cacciari M. , Ikonomu E. , Lenzi P. , Marinelli M.
Published: April 2008

Summary. The role of the renin‐angiotensin system in renal hypokalaemic dysfunction has been investigated by evaluating the effects of the angiotensin(AT)‐converting enzyme inhibition by enalapril. Healthy women were studied either in normal potassium balance (N3, n= 6) or moderate potassium depletion (KD3, n= 6). Potassium depletion (KD) was induced by low potassium dietary intake (10 mmol per day) and natriuretic treatment associated with replacement of net NaCl and water losses; the cumulative potassium deficit achieved was 214 54 mmol. The renal function and the urinary excretions of some prostanoids (PGE2, 6‐keto‐PGFlα, TxB2) were evaluated during hypotonic polyuria (oral water load) and subsequent moderate antidiuresis (lysine‐8‐va‐sopressin (LVP) low‐dose infusion). Paired studies were performed in absence (control) and presence of enalapril. Basal plasma renin activity (PRA) and urinary aldosterone excretion were determined before the water load of control studies.

Renal dysfunction typical of chronic KD occurred in the KD3 group, i.e. increase in PRA, decrease in creatinine clearance, depression of the diuretic response to water load, inhibition of distal fractional chloride reabsorption, and blunted efficacy of LVP in increasing the urinary solute concentration. The urinary prostanoid excretions were reduced. Basal urinary aldosterone excretion was not changed significantly. In KD3 group enalapril decreased mean arterial pressure (MAP), increased the plasma potassium concentration, improved the diuretic response to water load and corrected the impairment of the distal fractional chloride reabsorption. Despite the decrease in MAP enalapril did not affect significantly the creatinine clearance. Neither urinary prostanoid excretions nor the renal response to LVP were affected by the drug. The data suggest that in KD the increased activity of the renin‐angiotensin system affected the renal function both through direct effects and through effects dependent on the angiotensin‐supported secretions of aldosterone and probably of vasopressin. Finally, by comparing the effects of enalapril and indomethacin in experimental groups with an equivalent degree of KD, evidence is provided in favour of the interaction between renin‐angiotensin and prostanoid systems in controlling the glomerular filtration rate and the salt and water handling by renal tubules.,
Haematological status in elite long‐distance runners: influence of body composition
Authors: Suetta C. , Kanstrup I.‐L. , Fogh‐Andersen N.
Published: April 2008

SUMMARY. In 10 female and eight male Danish elite middle‐ and long‐distance runners, haematological status, including blood volume, was examined. Haemoglobin, haema‐tocrit and serum (s)‐ferritin concentrations were all within the normal range. In both men and women, blood volume, plasma volume and erythrocyte volume were increased in relation to various reference values. However, the runners had a low body weight due to a reduced fat level, 9‐5% (7‐3‐15‐1%) fat for the women, 5–9% (5‐0‐8‐8%) fat (median and ranges) for the men, measured by dual‐energy X‐ray absorptiometry (DEXA) scanning. When the runners' body weights were ‘normalized’ to a reference population (25% fat for women, 15% fat for men), only plasma volume remained increased in relation to body weight for the women, whereas all the volumes remained increased for the men. This confirms that endurance training induces a true increased plasma volume. The lower erythrocyte volume in the women compared with the men could be a consequence of the generally poorer iron status in the women, indicating that a combination of haemolysis, menstruation and low caloric (iron) intake makes it difficult for trained women to obtain optimal effects on erythrocyte volume equal to those obtained by trained men. Furthermore, the study emphasizes the importance of taking body composition into consideration when comparing well‐trained athletes with a reference population.
Environmental enrichment in steelhead (Oncorhynchus mykiss) hatcheries: field evaluation of aggression, foraging, and territoriality in natural and hatchery fry
Authors: Tatara Christopher P , Riley Stephen C , Scheurer Julie A
Published: April 2008

Reforms for salmonid hatcheries include production of hatchery fish with behavioral characteristics similar to wild conspecifics. Enrichment of the hatchery environment has been proposed to achieve this goal. Field experiments of steelhead (i.e., sea-run rainbow trout, Oncorhynchus mykiss) fry from a common stock reared under natural (i.e., stream), enriched hatchery, and conventional hatchery conditions indicated no significant differences in the rates of foraging or aggression between rearing treatments. However, the rates of foraging and aggression of natural fry were significantly affected by the type of hatchery fry stocked with them. Natural steelhead fry fed at lower rates and exhibited higher rates of aggression when stocked with steelhead fry raised in enriched hatchery environments. Territory sizes of steelhead fry ranged from 0.015 to 0.801 m2; were significantly, positively related to body length; and were not significantly different between rearing treatments. We conclude that hatchery steelhead fry released into streams establish territories that are proportional to their body length and similar in size to territories of natural steelhead fry. Our results indicate that both conventional and enriched hatchery environments produce natural social behaviors in steelhead released as fry and that fry from enriched hatchery environments may alter the foraging and aggressive behavior of natural, resident steelhead fry.
SPATIAL MODULATION OF ORDER PARAMETERS AND CRITICAL DIMENSIONS
Authors: BABICH A. V. , BEREZOVSKY S. V. , KLEPIKOV V. F.
Published: April 2008

Critical phenomena in systems which have a joint multicritical and Lifshitz-point-like behavior are investigated. An expression for the upper critical dimension of such systems is found. A condition of the variational scale invariance of the considered model is specified. If the space dimension coincides with the upper critical dimension, then the critical behavior of the fluctuation correction to the heat capacity is similar to that of the heat capacity without order parameter modulation.
The Development of Malay Editorial Cartoons
Authors: Mahamood Muliyadi
Published: April 2008

This essay examines the development of Malay editorial cartoons by focusing on styles and themes used since their first publication in the press of the 1930s. The discussion is based on the nature of the press and its historical background, factors that have influenced the form and content orf the cartoons. By analysing pre-independence and post-independence cartoons, the essay also demonstrates the influence of cultural and political factors on the development of the styles and themes of Malay editorial cartoons.
Consolidating Indian Identities in Post-Independence Singapore: A Case Study of the Malayalee Community
Authors: Gomez James
Published: April 2008

This paper examines the changing role of national and ethnic identity in post-independence Singapore. It argues that in comparison with 10-15 years ago, ethnic identities have gained importance over the national one. Examining the case of the Indians, in particular, that of the Tamil-speaking community, the paper argues that conditions for preserving the identity of the Tamil community are much improved. This is also true for the Sikh community. However, for the Malayalee community, given its fragmented nature, the prospects look bleak. The inability to gather the various segments of the community into a collective working whole is central to its problems. There is also a division between the younger and older members of the community. The younger Malayalees, having been socialized differently from the older generation in post-independence Singapore, find the current calls to return to ethnic roots unconvincing. The deliberations surrounding identity maintenance within the Malayalee community are sociologically interesting. They illustrate how recent national policies affect ethnic identity maintenance in contemporary Singapore.