bluuebunny/crossref_metadata_2025 huggingface dataset:
Non‐invasive variant of Gorlin formula can be used to identify severe aortic stenosis
Authors: Wandt B. , Sorgaard F. , Bojö L.
Published: April 2008

Summary. In recent years the continuity equation has been established as a valuable non‐invasive method for calculating aortic valve area. The continuity equation cannot be used if there is calcification or sub‐valvular stenosis in the left ventricle‐outflow tract, because the area of the outflow trace is not circular in those cases. The authors have tested the value of a non‐invasive variant of the Gorlin formula, as an alternative method of identifying severe aortic stenosis. They examined 32 consecutive patients with aortic stenosis with both methods. Seventeen patients had severe stenosis (valve area^0–7 cm2), calculated by the continuity equation. The other 15 patients had moderate stenosis (valve area 0–7–1–0 cm2). Using the non‐invasive variant of the Gorlin formula, the authors were able to identify 16 of the 17 cases with severe stenosis, thus showing that the method is useful for identifying severe aortic stenosis. (P<0–001 by x2‐test).
Knee extension strength and walking speed in relation to quadriceps muscle composition and training in elderly women
Authors: Sipilä S. , Suominen H.
Published: April 2008

Summary. Knee extension strength, walking speed, quadriceps muscle mass and composition of the muscle compartment were studied in 66 to 85‐year‐old female athletes and controls. Maximal voluntary knee extension force, force/body mass, extension torque, torque/body mass and walking speed were higher for the athletes than the controls. A muscle index indicating intramuscular fat and connective tissue measured using ultrasonography was lower for the athletes than the controls. There were no differences between the study groups in knee extension force related either to cross‐sectional area (CSA) or lean tissue area (CSAL) of the quadriceps. Within the subgroups, there was no significant correlation between knee extension torque and CSA or CSAL of the same muscle. In the athletes high knee extension torque/body mass was related to a low muscle index and high walking speed to a low relative proportion of fat in the muscle. The muscle index was lower the more kilometers trained during the preceding year. In the controls high knee extension torque/body mass and high walking speed were related to a low relative proportion of fat. Knee extension torque and walking speed were higher the more kilometers walked during the preceding year. The results indicate that elderly female athletes have superior muscle performance compared to their age‐peers. Performance in a maximal isometric strength test in elderly women is not clearly related to muscle mass. However, to some extent it is related to the composition of the same muscle, especially the degree to which fat is infiltrated into the muscle.
High hydrostatic pressures in traumatic joints require elevated synovial capillary pressure probably associated with arteriolar vasodilatation
Authors: Ahlqvist J. , Harilainen A. , Aalto K. , Sarna S. , Lalla M. , Österlund K.
Published: April 2008

Summary. Three out of the four Starling pressures were determined at arthroscopy of traumatic effusions of the knee. The range of the joint fluid hydrostatic pressure Pjointwas 5–83 cmH2O (0–5–8T kPa, 4–61 mmHg), that of the colloid osmotic pressure difference COPplasma‐COPjoint 0–21–7 cmH2O. In 11 of 15 cases the sum Pjoint+COP difference exceeded 32–6 cmH2O (3–19 kPa, 24 mmHg), a high estimate of average capillary pressure at the level of the heart. The number of ‘exceeding’ cases was 8/15 if only 80% of the COP difference was considered effective. Pjomt and the COP difference oppose filtration of fluid from plasma into joints, indicating that mean capillary pressure, the only Starling pressure not determined, was elevated unless the effusions were being resorbed back into the blood. The findings can be explained by tamponade compensated by arteriolar vasodilatation, suspected to be metabolically mediated.
Skin microcirculatory and thermal changes in elderly subjects with early stage of pressure sores
Authors: Schubert V. , Perbeck L. , Schubert P.‐Å.
Published: April 2008

Summary. Elderly subjects are prone to develop pressure sores over the sacrum area mainly due to external pressure and shear effects which negatively affect the skin microcirculation. The aim of the study described here was to measure skin microcirculatory and thermal changes in twelve elderly patients with an early stage of pressure sore and in ten elderly subjects without pressure sore. The total skin microcirculation at a damaged risk area, the sacrum, and a reference area of undamaged skin over the gluteal region, was evaluated using the laser Doppler fluxmetry. The nutritive transport of small solutes, characterized by the transcapillary exchange of sodium fluorescein, was evaluated using the fluorescein flowmetry technique. The skin temperature was measured with a thermoelement.

The skin microcirculation at the area with an early stage of pressure sore was significantly higher than at undamaged skin as measured by both techniques. The total microcirculatory blood flow increased > 16 times (P < 0–001) and the nutritive transport 5 times (P < 0–01) compared to the reference value, and the calculated blood flow of subpapillary tissue layers increased 17–19 times (P < 0–001). However, the skin temperatures in damaged and undamaged skin did not differ significantly.

These results show an increased skin microcirculation in the early stage of pressure sores but no increase in skin temperature. The more strongly increased skin blood flow in subpapillary tissue layers effectively conducts away the heat caused by the damage and the increased metabolic activity.
Diameter and velocity changes in the femoral vein during thermal stress in humans
Authors: Abraham P. , Leftheriotis G. , Desvaux B. , Saumet M. , Saumet J. L.
Published: April 2008

Summary. Unlike most studies on deep veins performed with simultaneous suppression of cutaneous blood flow, a sonographic study of femoral diameter and blood flow velocity changes in response to thermal stress was performed while cutaneous flow was preserved. In 11 normal subjects, mean peak blood flow velocity and diameter of the femoral vein were measured at rest and during indirect whole body heating and cooling. Mean peak venous blood flow velocity was 0–12 0–06 m s‐1 at rest, 0–35 0–23 m s‐1(P < 0–001) during heat stress, and 0–13 0–07 m s‐1 during cold stress (NS). Femoral venous diameter was 5‐3 0–9 mm at rest, 5‐l l‐0 mm (P < 0–05) during warming, and 5‐4 81‐0 mm (NS) during cooling. This study showed a decrease in diameter during thermal stress. However, as mean femoral venous blood‐flow velocity was doubled during heat stress, femoral venous blood flow was increased. Thus, it is suggested that during heat stress part of the increase in cutaneous flow is returned through deep veins.,
Assessment of coronary artery stenosis pressure gradient by quantitative coronary arteriography in patients with coronary artery disease
Authors: Atar D. , Ramanujam P. S. , Saunamaki K. , Haunsø S.
Published: April 2008

Summary. The aim of the study described here was to correlate coronary artery (CA) stenosis pressure gradients calculated by quantitative coronary arteriography (QCA) to invasively measured transstenotic pressure drops in patients with anginal symptoms and with known or suspected coronary artery disease. Furthermore, the known mathematical models are improved by introducing (1) pressure catheter‐corrected minimal stenosis area, (2) modification of flow assumptions, and (3) stenosis exit angle.

Included in the study were 45 patients with 61 stenoses. The visually estimated CA lesion severity in these non‐complex stenoses was in the equivocal range of 40–70%. All measurements were performed after intracoronary administration of nifedipine and nitroglycerine. Stenosis dimensions were assessed from magnified cinefilms, using handheld calipers.

Highly significant overall correlation was found between measured and calculated pressure gradients with correction for the impact of the intracoronary catheter (P < 0–00001, r= 0–84). In particular, a substantial number of stenoses with haemody‐namically‐insignificant pressure gradients were identified by hydrodynamic calculations. In conclusion, the great majority of the coronary artery stenoses could be classified reliably by QCA as being haemodynamically insignificant or significant, respectively.,
Local cooling prolongs oesophageal transit in humans
Authors: Jørgensen F. , Hesse B.
Published: April 2008

Summary. The influence of local cooling on oesophageal transit was studied in eight healthy volunteers by oesophageal radionuclide transit. Compared with lukewarm (18C) water a significantly prolonged mean transit time (MTT) was found after ingestion of cold liquid (4C) and a slightly shorter MTT with 50C. The effect was of short duration lasting less than 2 min.

The effect of atropine, morphine and naloxone, on the influence of local cooling was evaluated. Morphine (7‐5 mg i.v.) abolished the effect of cooling on MTT. Naloxone (1–6 mg i.v.) reduced the effect of cooling, but the difference between 4C and 19C was significant still. Atropine (1 mg i.v.) had no effect on the increase in MTT at 4C.

It is concluded that in humans local cooling increases oesophageal MTT. Local warming shortened MTT slightly. The abolishment of the influence of cooling by morphine suggests that opioids may be involved.,
Electrocardiographic changes in stroke patients without primary heart disease
Authors: Lindgren A. , Wohlfart B. , Pahlm O. , Johansson B. B.
Published: April 2008

Summary. Consecutive electrocardiograms were recorded in 28 stroke patients without signs of primary heart disease. Individuals with subarachnoidal haemorrhage, or electrolyte disturbances were excluded. A computerized tomography of the brain was performed in each case and showed a cerebral haemorrhage (n= 4), cortical infarction (n= 6), subcortical infarction (n= 14) and normal finding (n= 4). One patient developed atrial fibrillation but no other case of serious disturbances in rate or rhythm occurred. None developed AV block, bundle branch blocks or significant changes in QRS complexes. The most common abnormalities in ECG were transient STT changes in lateral leads, which were seen in 13 cases. The typical findings were flat or slightly negative T waves, horizontal or down‐sloping ST segments and sometimes a small ST depression. In no case did ECG show typical signs of acute myocardial infarction. A transient prolonged QT interval was seen in three patients and transient U waves in four. ECG did not correlate to the location of the vascular lesion seen on CT or the clinical outcome. It is concluded that STT changes of a small magnitude are seen in about half of the cases of stroke patients without primary heart disease and that they do not resemble the typical pattern of acute myocardial ischaemia.,
Effect of epidural anaesthesia on dorsal pedis arterial diameter and blood flow
Authors: Rørdam P. , Olesen H. L. , Sindrup J. , Secher N. H.
Published: April 2008

Summary.In nine subjects the influence of low (LE: blockade at or below the umbilicus; Th. 10) and high epidural anaesthesia (HE: block above the umbilicus) on vascular tone was evaluated by high frequency ultrasound (20 mHz) determined luminal diameter and a Doppler (8 mHz) assessment of mean blood flow velocity (Vmean) in the dorsalis pedis artery. The LE was induced by 0–5% bupivacain through a catheter at L3‐L4, and HE was established by further infusion. Resting blood pressure and heart rate were not affected by LE or HE. One subject developed selective thoracic anaesthesia, and another was blocked on the contralateral side only. In the seven adequately blocked subjects, the luminal diameter of the dorsalis pedis artery increased from 1.70 (1.25–1.93) to 1.90 (1.75–2.23) mm during LE (+12%) and further to 2.08 (1.83–2.96) mm during HE (22%;P<0.05). The Vmeanwas similar during control (7 [4–26] cm s‐1) and LE (12 [4–55] cm s‐1), but increased during HE to 35 (12–78) cm s‐1(+500%;P<0.05). Thus, arterial blood flow was higher during LE (21 [7–98] ml min‐1; +263%) and HE (94 [21–177] ml min‐1; +1175%) than at rest (8 [7–36] ml min‐1;P<0.05). This study quantified the importance of sympathetic nerve activity for vascular tone and in turn blood flow in an artery of a resting human limb, as the diameter and Vmeanincreased with progressive epidural anaesthesia.
Increased transcapillary escape rate of albumin in elderly subjects due to long‐term smoking habits
Authors: Jensen E. W. , Espersen K. , Knudsen J. H. , Nielsen S. L.
Published: April 2008

Summary. Transcapillary escape rate of albumin (TER) expressed as percentage decrease in specific activity of plasma albumin per hour was measured in 44 healthy male subjects, 10 young non‐smokers (median age 24.0 years, range 21–33), 10 young smokers (30.5 years, range 27–36), 10 elderly non‐smokers (64.0 years, range 51–75) and 14 elderly smokers (61.5 years, range 54–69). In addition urinary albumin excretion rates were measured in 15 of the elderly subjects. The subjects were investigated after overnight fasting and abstention from tobacco. Median TER was 7.33% (interquartile range 5.82–9.90) in the elderly smoking subjects. This value was significantly elevated as compared to elderly non‐smokers, 4.47% (2.93–5.83), young non‐smokers, 3.70% (2.24–6.30) and young smokers, 4.25% (2.80–4.44). A statistically non‐significant (P=0.064) tendency of a higher urinary albumin excretion rate was observed in elderly smokers. This agrees with other investigations showing slightly increased albuminuria in smokers compared with non‐smokers. The differences were not related to differences in blood pressure, plasma cholesterol, weight, or abuse of alcohol in the elderly subjects. Diabetic subjects with an increased TER to levels comparable with levels in long‐term smokers have increased urinary albumin excretion rates, which seems to be greater than in long‐term smoking subjects.

It is suggested that increased TER in long‐term smokers may indicate a vascular dysfunction affecting either capillary permeability or endothelial surface area.
Cardiovascular, plasma norepinephrine, and thermal adjustments to prolonged exercise in young and older healthy humans
Authors: Davy K. P. , Johnson D. G. , Seals D. R.
Published: April 2008

Summary.We tested the hypothesis that the whole body energy expenditure, plasma norepinephrine, cardiovascular, and internal body temperature adjustments to prolonged submaximal exercise (i.e., ‘cardiovascular drift’) performed at the same per cent of peak oxygen uptake (per cent VO2peak) under thermoneutral ambient conditions would be smaller in older compared to young non‐physically trained men. Healthy young (25±1 years; VO2max = 49.3±1.6 ml kg‐1min‐1;n=6) and older (66±2 years;VO2max = 31.5±2.3 ml kg‐1min‐1;n=6) untrained men with similar levels of chronic physical activity were studied during pre‐exercise standing rest and serially during 45 min of constant load treadmill walking at ˜65%VO2peak (Ta=˜23±C; ˜40 RH). There were no group differences at rest. From rest to 5 min of exercise, the increases in heart rate were less (P<0–05), the changes in arterial blood pressure and per cent δ blood volume were not different, and the rise in plasma norepinephrine concentration was greater (P<0–05) in the older menvs.young controls. Consistent with our hypothesis, the increases in rectal temperature and plasma norepinephrine concentrations from 5 to 45 min of exercise were smaller in the older men (1.06–0.18vs.1.46±0.16±C and 110±132vs.443±189%, respectively,P<0.05). In contrast, the progressive increases in KO2, heart rate, and perceived effort, as well as the time‐dependent reductions in systolic, mean and diastolic arterial blood pressure and per cent δ blood volume, were not different in the two groups. Thus, the whole body energy expenditure and selected cardiovascular adjustments to prolonged submaximal treadmill exercise performed at the same per centVO2peak under comfortable ambient conditions are not different in healthy, physical activity‐matched young and older men, despite a smaller elevation in internal body temperature in the latter.
Pilocarpine iontophoresis test: an index of physiological sweat secretion?
Authors: Hjortskov N. , Jepsen L. T. , Nielsen B. , Juul A. , Skakkebæk N. E.
Published: April 2008

Pilocarpine iontophoresis test: an index of physiological sweat secretion?

Summary. The pilocarpine iontophoresis test (P‐test) is used as a predictor of the capacity to produce sweat. Therefore, we studied the reproducibility of this test in 12 normal subjects on 10 consecutive days. Furthermore, we determined whether the P‐test reflects whole‐body and regional sweat secretion during exercise in the heat. Finally, we determined whether the P‐test stimulates the eccrine sweat glands to maximal sweat secretion. Six growth hormone‐deficient (GHD) patients who are known to have decreased sweating, and 11 healthy control subjects were studied. To induce maximal sweat secretion, the patients exercised on a bicycle ergometer at a workload corresponding to 40% of their maximal aerobic power (VO2max). The 11 healthy subjects exercised at a workload of 150 W. All subjects exercised for 60 min in ambient air at 35°C, with 50% relative humidity. The P‐test showed a mean day‐to‐day variation of 20‐8% between individual subjects. There was a significant positive correlation between the P‐test and regional sweat secretion (r2=0.74). The correlation coefficient (r2) was 0.50 for the correlation between the P‐test and whole‐body sweat secretion, and 0.52 for the correlation between regional sweat secretion and whole‐body sweat secretion. We conclude that the pilocarpine iontophoresis test reflects heat‐ and exercise‐induced sweating capacity. However, this test does not induce maximal sweating, and it cannot be used as a single reliable predictor of whole‐body sweating, due to considerable day‐to‐day variation.
Exercise capacity in heart failure patients: relative importance of heart and skeletal muscle
Authors: Magnusson G. , Kaijser L. , Rong H. , Isberg B. , Sylvén C. , Saltin B.
Published: April 2008

Summary. The knee extensor and the whole‐body exercise capacities were measured in 11 chronic heart failure (CHF) patients and 11 healthy age‐ and sex‐matched controls, and were related to ejection fraction and to biochemical and histochemical markers of the musculature.

The CHF patients had a 39% lower maximal oxygen uptake measured on an ergometer cycle than the healthy controls (1.54±0.57 vs. 2.51±0.70 1 min‐1, P < 0.001). The low exercise capacity was markedly related to the ejection fraction (r =0.77, P < 0.001)TThe maximal strength of m. quadriceps femoris was 15% lower in the CHF patients than in the controls (P < 0.05). The cross‐sectional area (CSA) of m. quadriceps femoris explained 55% (r =0.74, P < 0.001) of the difference in strength between both groups. The endurance capacity of m. quadriceps femoris was 30% lower in CHF patients than in controls, partly as a result of the 25% lower capillary density (P < 0.05) and the 27% lower aerobic enzyme capacity (P < 0.05), as estimated by the citrate synthase activity, in the CHF patients. The citrate synthase activity correlated with the maximal oxygen uptake (r =0.61, P < 0.05). Moreover, the ejection fraction, together with the CSA of m. quadriceps femoris, explained 75% (r =0.86, P < 0.01) of the difference in maximal oxygen uptake between CHF patients and controls.

These results demonstrate that CHF patients have both a lower local and a lower whole‐body work capacity than healthy controls. This is a function of a smaller leg muscle mass and a lower capillary density and mitochondrial enzyme capacity in the CHF patients; however, a lowered pump capacity of the heart is the factor which limits the exercise capacity the most.
Cardiac sympathovagal balance during sleep apnea episodes
Authors: Vanninen E. , Tuunainen A. , Kansanen M. , Uusitupa M. , Länsimies E.
Published: April 2008

Summary. The main acute cardiovascular effects of obstructive sleep apnea syndrome (OSAS) are elevation of blood pressure and reflectory bradycardia, which are followed by an abrupt tachycardia on resumption of breathing. This haemodynamic instability is related to hypoxemia and arousal, and may lead to increased risk from cardiac arrhythmias and sudden cardiac death, as well as to the development of chronic arterial hypertension, in these patients. The aim of this study was to apply frequency domain analysis of heart rate variability (HRV) measured from continuous electrocardiogram (ECG) recordings to evaluate how cardiac autonomic function, and especially cardiac sympathovagal tone, changes during sleep apnea episodes. We identified 41 apneas leading to more than 4%‐unit arterial oxygen desaturation in 12 patients (11 men, 1 women, age range 27–67 years). Frequency domain analysis of HRV was performed from ECG recordings using 4 min epochs starting 20 min before apnea began and lasting 20 min after the beginning of apnea. The mean (± SEM) fall in oxygen saturation during the apnea was 6.8±0.6%‐units. While high frequency band (HF, reflects cardiac vagal activity) remained unchanged, low frequency band (LF, mainly sympathetic activity) showed a constant increase, leading to significant change in the sympathovagal balance (LF/HF ratio). In conclusion, concordantly with previous peripheral sympathetic‐nerve recordings, frequency domain analysis of HRV is able to detect sympathetic activation during sleep apnea episodes, leading to marked change in the sympathovagal balance.
The concentrations of free amino acids in human liver tissue obtained during laparoscopic surgery
Authors: Barle H. , Ahlman B. , Nyberg B. , Andersson K. , Essén P. , Wernerman J.
Published: April 2008

Summary. The concentrations of the free amino acids in individual tissues gives information concerning amino acid, energy and protein metabolism. In muscle and intestinal mucosa, different metabolic states are distinctly characterized by an altered free amino acid pattern. Furthermore, the patterns are quite different in individual tissues. So far, liver tissue has not been investigated systematically in this respect. The aims of this investigation were to establish a standardized sampling procedure for liver tissue during laparoscopic surgery and to characterize the free amino acid concentrations in human liver tissue. Aspartate was the most abundant amino acid in the liver, followed by taurine, glutamine, glutamate, glycine and alanine. These six, and most abundant, amino acids constitute 90% of the total hepatic amino acid concentration. In the future, liver tissue sampling during laparoscopic surgery may be used as a model for investigating the influence of nutrition and hormones on hepatic amino acid and protein metabolism in man.
Relationships between field fitness test and basal serum testosterone and Cortisol levels in soccer players
Authors: Bosco C. , Tihanyit J. , Viru A.
Published: April 2008

Summary. The aim of this study was to investigate the existence of a relationship between performance capacities and blood levels of testosterone (T) and Cortisol (C). Thirty‐two professional soccer players volunteered for the study. Morning levels of hormones were plotted against results of maximal vertical jump with a preparatory counter‐movement (CMJ), 30 m running, and Cooper's 12‐min running test. The serum T was positively related to both CMJ and average running speed (r= 0.43 and r= 0.47, respectively). Serum levels of C and T were in negative correlation (r= ‐0.40 and r= ‐0.49, respectively) with the results of Cooper's test. It was concluded that athletes with better explosive strength and sprint running performances have a higher basal level of testosterone. The results suggest a relationship between testosterone production and development of fast twitch muscle fibres in athletes.
Ex Ante Impact Assessment under Imperfect Information: Biotechnology in New Member States of the EU
Authors: Demont Matty , Cerovska Marie , Daems Wim , Dillen Koen , Fogarasi József , Mathijs Erik , Muška František , Soukup Josef , Tollens Eric
Published: April 2008

Some argue that the lack of modern agricultural development in the former socialist countries of Central and Eastern Europe has made cutting‐edge biotechnology attractive. However, enthusiasm for planting genetically modified (GM) crops varies greatly in the enlarged European Union (EU) and especially among the New Member States (NMS); the Czech GM maize area is progressively growing whereas Hungary imposed a de facto ban on GM crops. Remarkably, the Hungarian ban was not supported by any cost–benefit assessment. In the literature, ex ante impact assessments of monopolistically priced technologies are often based on cross‐sectional comparisons of average cropping budgets. Such assessments ignore heterogeneity of farmers and underestimate the true impact of these technologies because of homogeneity bias. Therefore, we propose an improved method by explicitly modelling farmer heterogeneity under imperfect information, and assess the potential value and benefit sharing of GM crops in the two NMS using a stochastic partial equilibrium model. The total potential value of GM crops is estimated at €82 million for both countries, of which €60 million (73%) accrues to farmers and €22 million (27%) to the gene developers and the seed industry. This is in line with the literature on global benefit sharing of first‐generation GM technologies.
Time to Symptomatic Vascular Stenosis at Different Locations in Patients with Arteriovenous Grafts
Authors: Bozof Ryan , Kats Mark , Barker Jill , Allon Michael
Published: April 2008

Most arteriovenous grafts fail due to irreversible thrombosis, superimposed on hemodynamically significant vascular stenosis. Previous studies observed the highest frequency of stenosis at the venous anastomosis, without addressing the timing of stenosis. The present study quantified time to symptomatic stenosis at different vascular locations, and related it to permanent graft failure. A prospective computerized vascular access database was queried retrospectively to identify 309 hemodialysis patients receiving new upper extremity grafts during a 4‐year period at a large dialysis center. For each vascular site we calculated the time to symptomatic stenosis using survival techniques. The cumulative likelihood of symptomatic stenosis at 2 years was 67% for venous anastomotic stenosis, 19% for intra‐graft stenosis, 16% for venous outlet stenosis, 13% for central vein stenosis, and 5% for arterial anastomotic stenosis. The cumulative risk of graft failure at 2 years was 40%. Stenosis at the venous anastomosis was twice as likely as cumulative graft failure (hazard ratio [HR] 1.95; 95% confidence interval [CI], 1.65–2.52, p < 0.001). In contrast, intra‐graft stenosis was half as likely as cumulative graft failure (HR 0.45; 95% CI, 0.36–0.61, p < 0.001). Central vein stenosis was more likely in patients with a previous ipsilateral catheter compared with those without one (HR 2.40; 95% CI, 1.39–5.58, p = 0.004). Symptomatic stenosis occurs much earlier at the venous anastomosis compared with other vascular sites. Moreover, preexisting ipsilateral internal jugular dialysis catheters more than double the risk of central vein stenosis.
Anticonvulsive and antiepileptogenic effects of levetiracetam in the audiogenic kindling model
Authors: Vinogradova Lyudmila V. , Van Rijn Clementina M.
Published: April 2008

Summary

Purpose:To study anticonvulsive and antiepileptogenic effects of singe levetiracetam (LEV) administration in the model of audiogenic kindling.

Methods:Rats of Krushinsky‐Molodkina (KM) strain genetically susceptible to severe audiogenic seizures received one intraperitoneal injection of saline, low (6 mg/kg) or high (50 mg/kg) dose of LEV before or after audiogenic kindling. One hour postinjection, an audiogenic seizure was induced to assess anticonvulsive effect of LEV in nonkindled and kindled rats. To examine antiepileptogenic activity of LEV, nonkindled rats injected with the drug or saline were kindled with repeated sound stimulations. Audiogenic kindling development manifested in an appearance and progressive prolongation of an additional seizure phase, post‐tonic–clonus. The latency and duration of audiogenic seizures and the duration of every seizure phase (running, tonic, post‐tonic–clonic) were measured.

Results:One hour posttreatment, LEV dose‐dependently lengthened the latency and reduced the duration of audiogenic seizures in both nonkindled and kindled rats. The seizure shortening resulted from selective suppression of tonic and kindled post‐tonic–clonic phases. The dose of 50 mg/kg completely blocked tonic and clonic convulsions 1 h postinjection. The anticonvulsive effect of LEV was more pronounced in kindled than in nonkindled rats. Single LEV injection in the dose of 50 mg/kg prior audiogenic kindling significantly suppressed subsequent kindling progression indicating profound antiepileptogenic potency of the drug.

Conclusions:The present study shows that LEV exerts both short‐lasting anticonvulsive effect on audiogenic seizures and very long‐lasting antiepileptogenic effect on audiogenic kindling. Remarkably, a single injection of LEV is enough to significantly suppress kindling progression in KM rats.
Genetic influences on disordered eating behaviour are largely independent of body mass index
Authors: Slof‐Op ‘t Landt M. C. T. , Bartels M. , Van Furth E. F. , Van Beijsterveldt C. E. M. , Meulenbelt I. , Slagboom P. E. , Boomsma D. I.
Published: April 2008

Objective:  Prior studies suggest eating disorders and related characteristics are moderately to substantially heritable. We are interested in identifying the genes underlying disordered eating behaviour (DEB), and want to know how much of the genetic influence underlying DEB is attributable to genetic influences on body mass index (BMI).

Method:  Bivariate analyses were performed, in adolescent twins and siblings, to estimate the genetic and environmental contributions for DEB, BMI, and their overlap.

Results:  Shared genetic risk factors explained the overlap between BMI and DEB (genetic correlation was 0.43 in women, 0.51 in men). DEB was highly heritable in women (a2 = 0.65; a2 independent of BMI = 0.53) and moderately heritable in men (a2 = 0.39; a2 independent of BMI = 0.29). BMI was highly heritable in both men (a2 = 0.76) and women (a2 = 0.80).

Conclusion:  The entire correlation between DEB and BMI was explained by shared genetic risk, but the majority of genetic influences on DEB were due to genetic effects independent of BMI.
Severe vitamin B12 deficiency resulting in pancytopenia, splenomegaly and leukoerythroblastosis
Authors: Halfdanarson Thorvardur R. , Walker James A. , Litzow Mark R. , Hanson Curtis A.
Published: April 2008

Deficiency of vitamin B12 is a well known cause of megaloblastic anemia and pancytopenia. Splenomegaly and leukoerythroblastosis are much less well known manifestations of B12 deficiency. We report a B12 deficient female with severe pancytopenia including normocytic anemia who also had enlarged spleen and circulating nucleated red blood cells as well as circulating immature myeloid cells. Although these findings are reported in the earlier literature, more modern reviews of the subject often fail to mention this association. We review the literature on these unusual manifestations of B12 deficiency and remind clinicians that splenomegaly and erythroblastosis can serve as diagnostic clues in cases of severe megaloblastic anemia secondary to B12 deficiency.
Nomogram of the cerebellar vermis height at birth in small‐for‐gestational‐age neonates
Authors: Zuccotti Gian Vincenzo , Pogliani Laura , Dilillo Dario , Lista Gianluca , Radaelli Giovanni
Published: April 2008

Aim: To establish a nomogram of the height of the cerebellar vermis at birth in small‐for‐gestational‐age neonates.

Methods: Eighty‐five consecutively born healthy singletons who were small for gestational age were enrolled in a cross‐sectional observational study. The height of the cerebellar vermis was measured by ultrasonography in the midsagittal plane. Reference intervals for the vermian height at 5th, 50th and 95th centiles were estimated at any week of gestational age using a mean and standard deviation model based on least squares polynomial regression.

Results: All attempts at obtaining neonatal vermian height were successful. Mean (standard deviation) maternal age was 29.6 (4.7) years; median parity was 1 (range, 1–3). No difference was found between males and females for the vermian height (mean difference [95% confidence interval], −0.03 [−0.16; 0.10] cm). Mean vermian height (in cm) against gestational age (in weeks) was suitably modelled by a quadratic–cubic polynomial (r2= 0.790, p < 0.0001) as 0.712 + 0.00129 × gestational age2− 0.0000053 × gestational age3 (SD =−1.009 + 0.0504 × gestational age −0.000014 × gestational age3).

Conclusion: A nomogram of the height of the cerebellar vermis at birth against gestational age was established for use in small‐for‐gestational‐age neonates.
EFFECT OF LOW‐MOLECULAR ADDITIVES ON PRECIPITATION OF POTATO FRUIT JUICE PROTEINS UNDER DIFFERENT TEMPERATURE REGIMES
Authors: BÁRTA JAN , HEŘMANOVÁ VERONIKA , DIVIŠ JIŘÍ
Published: April 2008

The effects of two mineral and two organic acids, four organic solvents (methanol, ethanol, 2‐propano and acetone) and three inorganic metal salts in combination with temperature regimes 0 and 22C on the yield and resolubility of potato tuber proteins were studied. Using acids, the yield of precipitated protein ranged from 22.3% (citric acid, 0C) to 54.5% (acetic acid, 22C) of total protein; however, the resolubility was generally very low. The precipitation with organic solvents resulted in significantly higher yield as well as resolubility (P < 0.05) when precipitated at low temperatures. The yield ranged from 23.4% (ethanol, 22C) to 64.5% (2‐propanol, 0C) of total protein. The use of the salts resulted in precipitates with high resolubility regardless of the temperature regimes. The yield of precipitated protein ranged from 25.8% (ZnCl2, 0C) to 86.4% (FeCl3, 0C) of total protein.

PRACTICAL APPLICATIONS

The work studied the possibility of isolation of native potato proteins from potato fruit juice (PFJ) resulting from starch manufacturing process. Ethanol and FeCl3 were evaluated as the most promising precipitators for the recovery of potato tuber proteins from PFJ. However, ethanol usage for industrial isolation of potato proteins is strongly limited by the temperature regime in contrast to FeCl3, which could be used in a much wider range of temperature regimes without significant difference in protein yield and resolubility.
A NEW METHOD FOR ELLAGIC ACID PRODUCTION FROM POMEGRANATE HUSK
Authors: LU JINGJING , YUAN QIPENG
Published: April 2008

Pomegranate (Punica granatum L.) husk, a by‐product of the pomegranate juice industry, is an inexpensive and abundant source of ellagic acid. Ellagic acid is widely used as functional food for its physiological functions. It is the breakdown product of ellagitannins. To date, the preparation of ellagic acid from pomegranate husk has not been reported. This article reports a new process for ellagic acid production from pomegranate husk by extraction of tannins followed by acid hydrolysis and purification by extraction and recrystallization. Several tests were conducted to obtain optimum conditions including extraction of tannins by varying solvents, acid concentration and reaction time for acid hydrolysis and the volume of methanol used for purification. Ellagic acid (3.5 g) with 90% purity from 100 g pomegranate husk was obtained. This new method is easy to scale up. All equipment used in this production process is widely used in food processing industry. The cost of production is low. It is suitable for industrial applications.

PRACTICAL APPLICATIONS

The production of ellagic acid is easier and the yield and purity of ellagic acid produced this way are higher than before. This method can be used not only for experiment in laboratory but also for industrial applications. The material – pomegranate husk – is a by‐product of the pomegranate juice industry, so it is very cheap and easy to get. High‐purity ellagic acid produced this way is sold to many companies back home and abroad. It is used as food additive and cosmetic material because of its antioxidant activity and whiteningfunction. The toxicity of pomegranate husk is lower than that of gallnut, which has been the main material of ellagic acid production in the past. Reagents are common and inexpensive; some of them are reusable.
MATHEMATICAL OPTIMIZATION FOR ENERGY CONSUMPTION DURING FREEZE‐DRYING OF COOKED BEEF SLICE
Authors: LUO RUIMING , ZHOU GUANGHONG
Published: April 2008

In this article, the results were the following: drying period 2.55 h, with sample thickness 4 mm, chamber pressure 56.66 Pa, heating board temperature 67.50C; productivity 164.81 g/m/h, with sample thickness 9.40 mm, chamber pressure 74.00 Pa, heating board temperature 77.00C; minimum energy consumption 52,738.33 KJ/kg (H2O), with sample thickness 4 mm, chamber pressure 57.14 Pa, heating board temperature 77.00C. The comparison between calculated and experimental results showed that the optimized values were very close to the experimental results.

PRACTICAL APPLICATIONS

In this study, the goal function is to minimize the energy consumption during freeze‐drying of cooked beef slice. The optimal objects could be obtained by nonlinear regression analysis of the simulated data, instead of the experimental results. Now the expectation has been put into practice and validated, not less than 15 experiments were reduced. It indicates that the optimization technique proposed in the article is a simple and convenient tool to minimize the energy consumption of the freeze‐drying process.
Involving local communities in amphibian conservation: Taipei frog Rana taipehensis as an example
Authors: LIN H.‐C. , CHENG L.‐Y. , CHEN P.‐C. , CHANG M.‐H.
Published: April 2008

Farmland is an important habitat for many amphibians. However, the widespread and prolonged use of agro‐chemicals creates predictable difficulties and limitations for the conservation of agrobiodiversity. Farmland is an ecosystem in which human forces are greatly involved; therefore, conservation of natural resources in agricultural ecosystems must also relate to the existence of humans in order to achieve its goal. The Taipei frog Rana taipehensis has become a seriously threatened species in Taiwan because of wetland destruction and extensive use of agro‐chemicals on farmland. Nowadays, the species can only be found in Taipei, Taoyuan, Tainan and Pingtung Counties. Since 1999, Taipei Zoo has been surveying the distribution of Taipei frogs in Sanzhi, a small town in northern Taiwan. Taipei Zoo has adopted a two‐pronged approach to its conservation project. Aside from collecting ecological data on Taipei frog populations, we also cooperated with a local school and the Tse‐Xing Organic Agriculture Foundation (TXOAF) to carry out habitat‐improvement work and community‐education programmes about wetland conservation. We persuaded and assisted a farmer to halt his use of pesticides and eventually adopt organic‐farming practices because his farm was located right in the centre of the Taipei frog's breeding habitat and our sampling area. We also helped the farmer to sell his organically grown water lilies to TXOAF in order to provide a long‐term and stable income. From October 2002, the farmer stopped using agro‐chemicals on his fields. Beginning in 2003, when the population of Taipei frogs was apparently increasing, the farmer also became a follower of an organic lifestyle and is proud of the Taipei frogs on his land.
Amphibian water quality: approaches to an essential environmental parameter
Authors: ODUM R. A. , ZIPPEL K. C.
Published: April 2008

Appropriate water quality is essential for maintaining and breeding amphibians in captivity. Aquatic systems that maintain water quality have been employed for many years in the aquaculture and aquarium industries. These techniques are now more commonly being utilized for amphibians. Using information from the work of the authors and published literature on amphibians and fish, benchmarks are provided for common water‐quality parameters for amphibians.
EXTREME COMPRESSION BEHAVIOUR OF SOLIDS BASED ON THE ROY-ROY INVERTED EQUATION OF STATE
Authors: CHAUHAN R. S. , LAL K.
Published: April 2008

An analysis has been presented using the Roy-Roy equation of state (EOS), which represents an extended and modified version of the Murnaghan EOS. It is found that the value of [Formula: see text] for various types of solids remain between 5/3 and 2. The Roy-Roy EOS has been found to become applicable for the core of the Earth, predicting the values of the pressure and bulk modulus in the range of seismological data. Modifications suggested recently to remove the shortcomings of the Murnaghan equation have been discussed. The maximum values of [Formula: see text] obtained from the Roy-Roy EOS for different inorganic solids and organic solids are also discussed.
DIFFUSIVE TRANSPORT OF PARTIALLY QUANTIZED PARTICLES: L log L SOLUTIONS
Authors: VAUCHELET NICOLAS
Published: April 2008

The paper is devoted to the analysis of a drift-diffusion-Schrödinger–Poisson (DDSP) system. From the physical point of view, it describes the transport of a quasi-bidimensional electron gas confined in a nanostructure. Existence, uniqueness and long-time behavior of a weak solution were already obtained in Ref. 8 for constant scalar diffusion matrices. Here, we develop an L log L existence theory for the DDSP system for a general class of smooth diffusion matrices. Our argument relies on a Trudinger estimate for the entropy functional and a sharp bound on the Hamiltonian's spectrum.
TRANSMISSION THROUGH A THICK PERIODIC SLAB
Authors: RAMDANI KARIM , SHIPMAN STEPHEN
Published: April 2008

For the scalar wave equation in periodic structures, we establish rigorously the manifestation of a spectral bandgap as a frequency interval of exponentially small transmission of energy through a slab of the crystal when the thickness of the slab tends to infinity. We extend the result to slabs that contain a planar defect for frequencies that do not coincide with guided mode frequencies for the defect. For one-dimensional crystals, we prove that the transmission approaches a nonzero value at guided mode frequencies and give an explicit formula for the transmission. The main analytical tool in the multidimensional case is the Calderón boundary integral projectors for the Helmholtz equation.
ON THE FOUNDATIONS OF CANCER MODELLING: SELECTED TOPICS, SPECULATIONS, AND PERSPECTIVES
Authors: BELLOMO N. , LI N. K. , MAINI P. K.
Published: April 2008

This paper presents a critical review of selected topics related to the modelling of cancer onset, evolution and growth, with the aim of illustrating, to a wide applied mathematical readership, some of the novel mathematical problems in the field. This review attempts to capture, from the appropriate literature, the main issues involved in the modelling of phenomena related to cancer dynamics at all scales which characterise this highly complex system: from the molecular scale up to that of tissue. The last part of the paper discusses the challenge of developing a mathematical biological theory of tumour onset and evolution.
Transmission Electron Microscopy of Multilayer Thin Films
Authors: Petford-Long Amanda K. , Chiaramonti Ann N.
Published: April 2008

The unique geometry of multilayer thin films, with layer thicknesses on the nanoscale, gives rise to a wide range of novel properties and behavior that are not observed in the bulk. The novel behavior is critically dependent on the microstructure of the films. This paper reviews the use of a range of transmission electron microscopy (TEM) techniques to elucidate the structure, chemistry, and properties of multilayer thin films. The paper includes a brief introduction to the technological applications to which multilayer thin films are suited, followed by a description of the various TEM techniques. The final section of the paper presents the application of these techniques to various multilayer thin film systems.
Wetting and Roughness
Authors: Quéré David
Published: April 2008

We discuss in this review how the roughness of a solid impacts its wettability. We see in particular that both the apparent contact angle and the contact angle hysteresis can be dramatically affected by the presence of roughness. Owing to the development of refined methods for setting very well-controlled micro- or nanotextures on a solid, these effects are being exploited to induce novel wetting properties, such as spontaneous filmification, superhydrophobicity, superoleophobicity, and interfacial slip, that could not be achieved without roughness.
Religion and Science: Beyond the Epistemological Conflict Narrative
Authors: Evans John H. , Evans Michael S.
Published: April 2008

Studies of the relationship between religion and science have traditionally assumed that any conflict that exists is based on epistemology. This assumption is built into the history of Western academic thought, the founding of sociology itself, as well as the common definitions of religion used by social scientists. This assumption has hindered the examination of the relationship between religion and science. We categorize studies of the relationship between science and religion into three groups: the symbolic epistemological conflict studies, the symbolic directional influence studies, and the social-institutional studies. We find that the social-institutional studies, which most closely examine actual public conflicts, do not presume that the conflict is over epistemological claims and offer a more general and fruitful approach to examining the relationship between religion and science.
Cardiac Remodeling in Obesity
Authors: Abel E. Dale , Litwin Sheldon E. , Sweeney Gary
Published: April 2008

The dramatic increase in the prevalence of obesity and its strong association with cardiovascular disease have resulted in unprecedented interest in understanding the effects of obesity on the cardiovascular system. A consistent, but puzzling clinical observation is that obesity confers an increased susceptibility to the development of cardiac disease, while at the same time affording protection against subsequent mortality (termed the obesity paradox). In this review we focus on evidence available from human and animal model studies and summarize the ways in which obesity can influence structure and function of the heart. We also review current hypotheses regarding mechanisms linking obesity and various aspects of cardiac remodeling. There is currently great interest in the role of adipokines, factors secreted from adipose tissue, and their role in the numerous cardiovascular complications of obesity. Here we focus on the role of leptin and the emerging promise of adiponectin as a cardioprotective agent. The challenge of understanding the association between obesity and heart failure is complicated by the multifaceted interplay between various hemodynamic, metabolic, and other physiological factors that ultimately impact the myocardium. Furthermore, the end result of obesity-associated changes in the myocardial structure and function may vary at distinct stages in the progression of remodeling, may depend on the individual pathophysiology of heart failure, and may even remain undetected for decades before clinical manifestation. Here we summarize our current knowledge of this complex yet intriguing topic.