Acta physiologica Hungarica最新文献

Unlabelled: This study has been conducted to determine whether mean values of peak oxygen consumption (VO(2peak)), anaerobic test parameters and knee isokinetic test measurements are different among guanine nucleotide-binding protein, beta-3 (GNB3) genotype groups in a group of basketball players.

Methods: Seventy-two healthy male (mean age, 22.9 ± 5.3 years) basketball players from the first division of national league participated. We studied GNB3 gene c.825C>T (rs5443) polymorphism, then divided the subjects into three groups as CC (n = 21), CT (n = 35), and TT (n =1 6). Mean VO(2peak), Wingate anaerobic test results, and isokinetic knee muscle strength measurements were compared among the genotype groups.

Results: Mean VO(2peak) (60.1 ± 3.9; 56.7 ± 3.6; and 57.8 ± 3.3, respectively, p < 0.01), mean anaerobic minimum power (5.1 ± 0.4; 5.3 ± 0.5; and 4.4 v 0.5 W/kg, respectively, p < 0.001), mean anaerobic power drop (57.0 ± 6.2; 54.2 ± 6.9; and 62.9 ± 5.3%, respectively, p < 0.001) were significantly different among the study groups, CC, CT, and TT. Individuals with TT genotype exerted lower performance in terms of isokinetic knee muscle strength.

Conclusion: The presence of 825T-allele may impair athletic performance and may serve as a genetic marker of low capacity for athletic performance in male basketball players.

Unlabelled: The association between metabolic syndrome (MS) and bone status remains controversial. We aimed to study the relationships between MS, bone mineral density (BMD), and bone metabolism in postmenopausal women.

Material and methods: MS was assessed in 218 white postmenopausal women. BMD (lumbar spine and hip) was measured by dual energy X-ray absorptiometry (DXA). Serum carboxyterminal cross-linked telopeptide of type 1 collagen (CTX), undercarboxylated osteocalcin (uOC), bone alkaline phosphate (BAP) and vitamin D were assayed.

Results: Postmenopausal women with MS had a significantly higher lumber spine BMD than women without MS (p < 0.05). A progressive increase of the BMD at both sites with the number of MS components was observed. Bone turnover markers and vitamin D levels were not significantly influenced by the presence of MS. BMD at both sites positively correlated with body mass index (BMI), waist circumference (WC) and glucose in unadjusted analysis. In multiple regression analysis, WC was independently associated with BMD at both sites, while hypertension was associated only with lumbar spine BMD.

Conclusions: In postmenopausal women, MS is associated with increased lumbar spine BMD and this relation is explained mainly by the higher BMI and WC in the MS group.

In order to determine whether local anesthetics directly affect the propagation and strength of myometrial contractions, we compared the effects of bupivacaine, ropivacaine, lidocaine and tetracaine on the contractions of myometrium isolated from pregnant and non-pregnant rats. Full-thickness myometrial strips were obtained from 18- to 21-day pregnant and non-pregnant Sprague-Dawley rats and incubated in an organ bath. When spontaneous contractions became regular, strips were exposed to cumulative concentrations of the four local anesthetics ranging from 0.01 to 300 μmol/L and the amplitude and frequency of contraction were recorded. All four compounds caused a concentration-dependent inhibition of the contractility of pregnant and non-pregnant uterine muscle. In pregnant myometrium, the concentration that caused 50% inhibition (IC(50)) was 100 μmol/L for bupivacaine, 157 μmol/L for ropivacaine, > 1000 μmol/L for lidocaine, and 26.3 μmol/L for tetracaine. In non-pregnant myometrium, the IC(50) was 26.9 μmol/L for bupivacaine, 40 μmol/L for ropivacaine, 384 μmol/L for lidocaine, and 7.4 μmol/L for tetracaine. These results suggested that local anesthetics do inhibit myometrial contractions in pregnant and non-pregnant rats in a concentration-dependent manner.

The roots of physiology - on the basis of a systematic study of the human body's functions and their correlation to anatomy - date back to the works of Aristotle. The pupil of Plato and the tutor of Alexander the Great was a one-man university, and his contributions to the medical sciences have been immense. His surviving works highlight the first serious approach towards the rejection of metaphysical and mythological thought, and have: (i) demonstrated a deep appreciation for a systematic, non-metaphysical study of the natural world, (ii) set the foundations of comparative and human anatomy, (iii) established the first (indirect) definition of the "physiologist", and (iv) exercised a dominant influence upon the subsequent history of Hellenistic, European and Arabic Medicine. The current letter provides a short commentary on the historical account of Physiology as a scientific field and underlines the unique legacy that Aristotle has provided us with.

Unlabelled: Genetic effects that contribute to the risk of developing chronic obstructive pulmonary disease (COPD) have been reported. Our purpose was to estimate the possible genetic influence on CT features related to COPD in twins.

Methods: Two COPD-discordant and one COPD-concordant monozygotic (MZ) twin pair, in addition to 2 control dizygotic (DZ) twin pairs underwent a low-dose high resolution computer tomography (HRCT) in inspiration and expiration (Philips Brilliance 16).

Results: Monozygotic twins were more similar in lung volume expiration and in air trapping score compared to dizygotics (382 cm(3) vs. 2303 cm(3) and 17.6% vs. 26.6%, respectively). In general, MZ twin pairs showed almost identical HRCT features independently of smoking attitude and COPD status. The dizygotic twin pairs showed larger differences in HRCT features compared to MZ twins.

Conclusions: Lung parenchymal and small airway changes (lung density, presence of bronchial wall thickening, bronchiectasis and/or mucus plug formation, air trapping and emphysema score) seem to be genetically associated traits, independently of smoking/COPD history. A future study with a larger sample size should confirm our findings.

The control of arterial pressure is a complex interaction of the long- and short-term influences of hormones, local vascular factors, and neural mechanisms. The autonomic nervous system and its sympathetic arm play important roles in the regulation of blood pressure, and overactivity of sympathetic nerves may have an important role in the development of hypertension and related cardiovascular disorders. The baroreceptor system opposes either increases or decreases in arterial pressure, and the primary purpose of the arterial baroreflex is to keep blood pressure close to a particular set point over a relatively short period of time. The ability of the baroreflex to powerfully buffer acute changes in arterial pressure is well established, but the role of the arterial baroreceptor reflex in long-term control of arterial pressure has been a topic of many debate and controversy for decades. The sympathetic nervous system and arterial baroreceptor reflex control of renal sympathetic nerve activity has been proposed to play a role in long-term control of arterial pressure. The aim of this paper has been to review the postulated role of sympathetic activation.

Blood flow restriction (BFR) combined with low load resistance training has been shown to result in muscle hypertrophy similar to that observed with higher loads. However, not all studies have found BFR efficacious, possibly due to methodological differences. It is presently unclear whether there are differences between cuffs of similar size (5 cm) but different material (nylon vs. elastic). The purpose was to determine if there are differences in repetitions to fatigue and perceptual ratings of exertion (RPE) and discomfort between narrow elastic and narrow nylon cuffs. Sixteen males and females completed three sets of BFR knee extension exercise in a randomized cross-over design using either elastic or nylon restrictive cuffs applied at the proximal thigh. There were no differences in repetitions to fatigue (marker of blood flow) or perceptual ratings between narrow elastic and narrow nylon cuffs. This data suggests that either elastic or nylon cuffs of the same width should cause similar degrees of BFR at the same pressure during resistance exercise.

As a prevention, a physically active lifestyle including the performance of weight-bearing exercises is important to enhance and maintain bone mineral content. Fifty young women were selected for the study. Twenty-five women carried out a specific training directed by a physiotherapist in the training group (TG), while 25 women were walking for 60 minutes in the control group (CG). Total and bone-specific alkaline phosphatase (ALP and BALP) and C-terminal cross-linked telopeptide (CTX) levels were measured at the beginning and at the end of exercise. The most remarkable change was seen in CTX levels (TG -28.89%, p < 0.001; CG -52.54%, p < 0.001), and there was also a significant difference in the values of CTX between TG and CG (p = 0.012). Therefore, walking more significantly reduced the level of CTX than special exercise. The decrease of BALP in TG was considerable but not significant (TG -4.63%, p = 0.091), while BALP levels dropped significantly in CG (-7.65%, p = 0.011), and there was a non-significant difference between the two groups (p = 0.22). Regarding the ALP level, a significant reduction was detected in TG and CG (-6.84%, p < 0.001 vs. -4.57%, p < 0.001). This study reveals that the 60-minute, middle-intensity training and the brisk walking have an immediate effect on bone metabolic markers.

The purpose of this study was to investigate the effects of three different distributions of aerobic training on the isokinetic strength and vertical jump performance [SJ, CMJ and Abalakov (ABA)] in thirty middle-aged endurance athletes (38.7 ± 9.8 yrs; 174.7 ± 6.5 cm; 72.0 ± 9.8 kg). Three zones of training were required to quantify volume of training: Zone 1, low-intensity-training < VT1; Zone 2, threshold-training, between VT1 and VT2; and Zone 3, high-intensity-training > VT2. The INC group (n = 10) began training in the Zone 1 and then gradually built up training in Zone 2 and Zone 3, thereby increasing the intensity of aerobic activity over the 4-week training period. The CON group (n = 10) performed the same activity every week in Zones 1, 2 and 3. The FRE group followed a free distribution of endurance training loads (n = 10). The results showed significant decreases in peak torque knee extension 30° (p < 0.05) in CON group and significant decreases (p < 0.05) in ABA in FRE group. Results provide a physiological basis to support several performance studies that consistently indicate 5 d·wk(-1) endurance training does not impair strength development over the short term. In conclusion, variations in volume and intensity in training groups did not interfere with isokinetic strength and vertical jump performance.

Discrepancies exist whether blood flow restriction (BFR) exacerbates exercise-induced muscle damage (EIMD). This study compared low-intensity eccentric contractions of the elbow flexors with and without BFR for changes in indirect markers of muscle damage. Nine untrained young men (18-26 y) performed low-intensity (30% 1RM) eccentric contractions (2-s) of the elbow flexors with one arm assigned to BFR and the other arm without BFR. EIMD markers of maximum voluntary isometric contraction (MVC) torque, range of motion (ROM), upper arm circumference, muscle thickness and muscle soreness were measured before, immediately after, 1, 2, 3, and 4 days after exercise. Electromyography (EMG) amplitude of the biceps brachii and brachioradialis were recorded during exercise. EMG amplitude was not significantly different between arms and did not significantly change from set 1 to set 4 for the biceps brachii but increased for the brachioradialis (p ≤ 0.05, 12.0% to 14.5%) when the conditions were combined. No significant differences in the changes in any variables were found between arms. MVC torque decreased 7% immediately post-exercise (p ≤ 0.05), but no significant changes in ROM, circumference, muscle thickness and muscle soreness were found. These results show that BFR does not affect EIMD by low-intensity eccentric contractions.