RELATIONSHIP BETWEEN NEURODYNAMIC CHARACTERISTICS AND FUNCTIONAL PREPAREDNESS OF MUSCLES IN ATHLETES OF DIFFERENT SPORTS

Aim. The article is aimed at studying the relationship between the neurodynamic characteristics of athletes of different sports and the indicators of physical fitness obtained during exercise tests. Materials and methods. The study involved male athletes aged 16–21 years, involved in swimming (20 people) and powerlifting (16 people), having sports ranks from the 2nd adult to a candidate for master of sports. The volume and concentration of attention, the speed of eye-hand coordination, the level of functional mobility, the strength of nervous processes, the response to a moving object and the tapping test were processed using an automated program. Indicators of aerobic and speed - strength fitness of the muscles of the lower extremities were determined by the cycle ergo meter tests. Results. Swimmers differed from power lifters by a smaller volume, but better concentration of attention, higher dynamism and strength of nervous processes, less pronounced excitement in the central nervous system, high rates of aerobic energy supply and a less pronounced correlation between the functional indicators and psychophysiological characteristics. In both groups, negative correlations of aerobic performance with the speed of visual motor responses and positive correlations with the balance of nervous processes were revealed. Speed-strength indicators are better for athletes with a high functional mobility, dynamism and strength of nervous processes. Conclusion. There is a correlation between the neurodynamic characteristics and indicators of functional fitness, which must be taken into account when interpreting the results of stress tests and developing individual recommendations based on the results of the examination.

P3463Cardiometabolic risk factors in women with a history of hypertensive disorders of pregnancy

Introduction

A history of hypertensive disorders of pregnancy (HDP) has the unique potential to identify women at higher risk of future maternal cardiovascular disease (CVD), for whom targeted risk-reduction interventions may be particularly helpful.

Purpose

The aim of the study was to assess the factors and biomarkers of cardiometabolic risk in women with a history of hypertensive disorders of pregnancy.

Methods

Cross-sectional study of risk factors and biomarkers of cardiometabolic risk among young women with a history of HDP in comparison with normotensive patients during pregnancy. 117 women were studied: gr. 1 – 33 with a history of HDP, 40 [40–43] years; gr. 2 – 44 without a history of HDP, 39 [32–43] years. The control group consisted of 40 patients, 25 [23–28] years. The time interval after delivery was on average 5 to 19 years. We measured serum glucose, insulin, HOMA-IR, lipids, leptin, adiponectin. Left ventricular mass index (LVMI) was estimated by TTE. Data are presented as M±SD and Me (Q25–Q75).

Results

Women with HDP more often had hypertension (n=27; 82%), obesity (n=20; 39%) and smoking (n=9; 27%), p1–2,3 <0.05. A higher plasma levels of glucose mmol/L (5.5±0.7 vs 5.2±0.6 and 5.1±0.5), leptin ng/ml (42 [30–50] vs 24 [13–32] and 19 [10–29]) and lower plasma levels of adiponectin were observed in gr.1 vs gr. 2 and controls. Mean value of LVMI (g/m2) was statistically higher in women with HDP vs. without HDP and controls (119.9±23.7 vs 85.9±15.2 and 77.6±11.3), p1–2,3 <0.05.

Conclusion

It is shown that in women with a history of HDP subsequent changes in carbohydrate and lipid metabolism in combination with arterial hypertension and abdominal obesity, which constitute a cluster of the metabolic syndrome, are revealed after careful examination. These changes are also accompanied by insulin resistance, hyperinsulinemia, adipokine imbalance and more pronounced target organ damage.

Abstract P1-14-01: Final analysis of overall survival (OS) for the epoetin alfa (EPO) phase 3 study, EPO-ANE-3010, of EPO plus standard supportive care (SOC) versus SOC in anemic patients with metastatic breast cancer (MBC) receiving standard chemotherapy

Background: In the interim analysis of study EPO-ANE-3010, for the primary endpoint of progression-free survival (PFS), the non-inferiority objective in ruling out a 15% increased risk in progressive death (PD) or death per investigator-determined PD was not achieved (JCO 34:1197-1207, 2016). PFS, based on independent review committee (IRC)-determined PD, however, met the non-inferiority criteria. At the interim analysis, OS with 1,337 deaths was reported; we now report the final analysis at 1,653 deaths and the updated PFS.

Methods: This multinational (19 countries and 132 participating sites), phase 3, randomized, open-label noninferiority study included anemic (≤11.0 g/dL hemoglobin) women receiving first- or second-line standard chemotherapy for MBC (Eastern Cooperative Oncology Group performance status of 0 or 1). Subjects were randomized (1:1) to receive either standard SOC for treatment of anemia plus EPO (40,000 IU subcutaneous) weekly up to 4 weeks after the last dose of cytotoxic chemotherapy, or SOC alone. The primary endpoint was PFS (using Cox's regression model). Secondary endpoints included OS, time to tumor progression (TPP), overall response rate (ORR) and safety assessments.

Results: A total of 2,098 subjects were enrolled (EPO plus SOC: n=1,050; SOC alone: n=1048). Demographic and baseline characteristics were well-balanced across the groups; median age was 52 years, most were white (67.5%) or Asian (30.5%) and median BMI was 26.0 kg/m2. Primary efficacy analysis (based on investigator-determined PD) showed a median PFS of 7.4 months for both groups (hazard ratio [HR], 1.094; 95% CI: 0.996, 1.201);upper bound exceeded prespecified noninferiority margin of 1.15. A 9% increased risk for PD/death in the EPO plus SOC group was observed and did not statistically rule out a 15% increased risk. Median PFS per IRC-determined PD was 7.6 months in both groups (HR, 1.028; 95% CI: 0.922, 1.146), this met pre-defined non-inferiority margin of 1.15 with a 3% risk increase in PD/death in EPO plus SOC group. At the final analysis for OS, median OS was 17.8 months in the EPO plus SOC group and 18.0 months in the SOC group; HR: 1.073 (95% CI: 0.974, 1.182); median TPP was 7.5 months in both groups (HR, 1.099; 95% CI, 0.998 to 1.210), and ORR was 50% in the EPO plus SOC group and 51% in the SOC group (odds ratio, 0.939; 95% CI, 0.789, 1.117). Red blood cell (RBC) transfusions were 5.8% versus 11.5% (P&lt;0.001), and thrombotic vascular events were 2.8% versus 1.4% (P=0.038), respectively, in EPO plus SOC group and SOC group. The incidence of death due to PD were similar in both groups (EPO plus SOC: 93%; SOC: 91%).

Conclusion:The primary endpoint, PFS based on investigator-determined PD, did not meet noninferiority criteria but for PFS based on IRC-determined PD, noninferiority criteria was met. Overall, this study did not statistically rule-out a 15% increased risk in PD/death. The final analysis did not show statistically different OS in the EPO plus SOC group versus the SOC group. No new safety signals were noted with EPO treatment and the results are consistent with the known safety profile of EPO.

Citation Format: Leyland-Jones B, Bondarenko I, Nemsadze G, Smirnov V, Litvin I, Kokhreidze I, Abshilava L, Janjalia M, Li R, Lakshmaiah KC, Samkharadze B, Tarasova O, Shparyk Y, Polenkov S, Vladimirov V, Han J, Safonov I, Appiani C, Leitz G. Final analysis of overall survival (OS) for the epoetin alfa (EPO) phase 3 study, EPO-ANE-3010, of EPO plus standard supportive care (SOC) versus SOC in anemic patients with metastatic breast cancer (MBC) receiving standard chemotherapy [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P1-14-01.

Effects of continuous and intermittent aerobic exercise upon mRNA expression of metabolic genes in human skeletal muscle

AIM

It is known that intermittent aerobic exercise training program is more efficient for the improvement of aerobic performance than continuous one but molecular mechanisms of such effects are purely understood. The aim of the present study was to compare gene expression of mitochondrial biogenesis regulators (peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α), mitochondrial transcription factors A (TFAM) and B2 (TFB2M) and genes involved in exercise-induced catabolic events (forkhead box O1 (FOXO1) and Atrogin-1) in human skeletal muscle after single continuous (CE) and intermittent (IE) aerobic exercise sessions, equalized thoroughly in duration and mean power output.

METHODS

Twelve physically active males performed CE (workload at lactate threshold [LT], 50 min) or IE ([3 min 81% LT+2 min 125% LT]x10). The biopsies were taken from m. vastus lateralis before and 1 h, 3 h, 5 h after the exercise.

RESULTS

The IE induced a 2-fold greater increase of PGC-1α and TFAM gene expression after 3 h and 5 h of recovery than CE. The increments of Atrogin-1 mRNA abundance were observed 3 and 5 h after IE only. The increments in FOXO1 mRNA level were revealed 1 h and 3 h after the IE and 3 h after the CE.

CONCLUSION

The results of the study suggest that higher potential of IE for the improvement of mitochondrial biogenesis than CE associated with more pronounced increase of PGC-1α and TFAM mRNA expression. Along with that, IE induces a higher increment of expression of FOXO1 and Atrogin-1 genes involved with exercise-induced catabolic events compared to CE.

Limits on neutrino emission from gamma-ray bursts with the 40 string IceCube detector

IceCube has become the first neutrino telescope with a sensitivity below the TeV neutrino flux predicted from gamma-ray bursts if gamma-ray bursts are responsible for the observed cosmic-ray flux above 10(18)  eV. Two separate analyses using the half-complete IceCube detector, one a dedicated search for neutrinos from pγ interactions in the prompt phase of the gamma-ray burst fireball and the other a generic search for any neutrino emission from these sources over a wide range of energies and emission times, produced no evidence for neutrino emission, excluding prevailing models at 90% confidence.

Extending the search for neutrino point sources with IceCube above the horizon

Point source searches with the IceCube neutrino telescope have been restricted to one hemisphere, due to the exclusive selection of upward going events as a way of rejecting the atmospheric muon background. We show that the region above the horizon can be included by suppressing the background through energy-sensitive cuts. This improves the sensitivity above PeV energies, previously not accessible for declinations of more than a few degrees below the horizon due to the absorption of neutrinos in Earth. We present results based on data collected with 22 strings of IceCube, extending its field of view and energy reach for point source searches. No significant excess above the atmospheric background is observed in a sky scan and in tests of source candidates. Upper limits are reported, which for the first time cover point sources in the southern sky up to EeV energies.

Limits on a muon flux from neutralino annihilations in the sun with the IceCube 22-string detector

A search for muon neutrinos from neutralino annihilations in the Sun has been performed with the IceCube 22-string neutrino detector using data collected in 104.3 days of live time in 2007. No excess over the expected atmospheric background has been observed. Upper limits have been obtained on the annihilation rate of captured neutralinos in the Sun and converted to limits on the weakly interacting massive particle (WIMP) proton cross sections for WIMP masses in the range 250-5000 GeV. These results are the most stringent limits to date on neutralino annihilation in the Sun.

Limits on the high-energy gamma and neutrino fluxes from the SGR 1806-20 giant flare of 27 December 2004 with the AMANDA-II detector

On 27 December 2004, a giant gamma flare from the Soft Gamma-Ray Repeater 1806-20 saturated many satellite gamma-ray detectors, being the brightest transient event ever observed in the Galaxy. AMANDA-II was used to search for down-going muons indicative of high-energy gammas and/or neutrinos from this object. The data revealed no significant signal, so upper limits (at 90% C.L.) on the normalization constant were set: 0.05(0.5) TeV-1 m;{-2} s;{-1} for gamma=-1.47 (-2) in the gamma flux and 0.4(6.1) TeV-1 m;{-2} s;{-1} for gamma=-1.47 (-2) in the high-energy neutrino flux.

Neurogenic constrictor response of isolated small renal arteries in rats after 2-week simulated microgravity

The study was aimed at investigation of the effects of 2-week tail suspension upon the constrictor responses of isolated small renal arteries in rats. 1st-2nd-order branches of renal artery were perfused with saline under the constant flow conditions. Constrictor responses to electrical stimulation of periarterial nerves, noradrenaline and serotonin were investigated. In post-suspension rats as compared to controls the response to nerve stimulation was slightly reduced during 15-Hz stimulation, but similar at smaller frequencies. Thus, simulated microgravity has no prominent effect of neurogenic responses of renal vessels, in agreement with non-changed density of periarterial adrenergic nerve plexus. Along with that, in post-suspension rats impairment of prejunctional sympathetic mechanisms might be compensated by augmented sensitivity of vascular smooth muscle to vasoconstrictors.

Effect of two-week tail suspension on forelimb and hindlimb [correction of hindlimd] small arteries in rats

This study was aimed at comparing the effect of 2-week tail suspension on the characteristics of median artery and saphenous artery isolated from forelimb and hindlimb, accordingly. The segments of arteries were mounted in two-channel myograph for recording their isometric wall tension. In post-suspension rats segments of saphenous artery showed augmented sensitivity to noradrenaline and serotonin. More than two-fold decreased of EC50 was observed both before and after endothelium removal. Along with that, the sensitivity of median artery segments to vasoconstrictors was similar in post-suspension and control rats. However, the diameter of relaxed median artery in post-suspension rats was increased. Relaxation to acetylcholine compared to controls was augmented in both vascular regions of post-suspension rats being more pronounced in saphenous artery preparations.

Hemodynamic changes in post-suspension rats during gradual hemorrhage

We examined the changes of hemodynamic parameters in nembutal-anesthetized rats during gradual hemorrhage (2 ml/100 g body weight during 30 min). In control rats blood pressure began to decline starting from 3rd min of bleeding and from 5th min it was accompanied by cardiac deceleration. Hindlimb vascular resistance was only slightly increased up to 15th min (by 20-30%) and then began to grow drastically. Less prominent changes of hemodynamics were observed in post-suspension rats. The results indicate that when activity of sympathetic nervous system is blunted with anesthetic post-suspension rats demonstrate higher hemodynamic stability during acute hemorrhage.

Transmitter characteristics of cutaneous, renal and skeletal muscle small arteries in the rat

AIM

We studied transmitter characteristics of proximal and distal arteries supplying skin (saphenous artery and its medial tarsal branch), kidneys (terminal branches of renal artery and interlobar arteries) and skeletal muscle (proximal and distal sections of external sural artery).

METHODS

Artery segments were mounted in an isometric myograph and intramural nerves were activated by electrical field stimulation. Adrenergic and purinergic components of the neurogenic response were blocked using phenoxybenzamine and alpha,beta-methylene adenosine triphosphate (mATP), respectively.

RESULTS

Arteries from skin or kidney developed rapid and prominent neurogenic contractile responses, with half-maximal amplitude reached within 5-15 s; responses in proximal vessels were greater than in distal vessels. Arteries from skeletal muscle responded to sympathetic stimulation with a moderate contraction developing over 1 min or more, the response of distal segments was greater than that of proximal segments. In skeletal muscle vessels the sympathetically evoked contraction was completely blocked by phenoxybenzamine, whereas in skin and renal vessels it was the combined effect of noradrenaline and adenosine triphosphate (ATP). Given alone, mATP did not change the magnitude of the response to nerve stimulation, but increased its latency and also potentiated the response to exogenous noradrenaline. In all vascular beds, distal vessels were more sensitive to noradrenaline and mATP.

CONCLUSION

It thus appears that the noradrenaline/ATP ratio of the sympathetic vasoconstrictor response differs between vascular beds in a way that is consistent with known differences in the selective regulation of regional vascular resistance by the sympathetic nervous system.

Long-term dynamics of blood pressure in intact and sympathectomized post-suspension rats

Low-frequency dynamics of mean arterial pressure (MAP) and pulse interval (PI) was studied in intact and sympathectomized rats after 2-week tail suspension. Correlation properties of long-term (f<0.8 Hz) MAP fluctuations were analyzed using R/S Hurst method. It was shown that time series of successive increments in MAP level display power-law fractal anticorrelations in wide range of time scales. After sympathectomy and/or suspension averaged Hurst exponents were more close to the value for uncorrelated random process (H=0.5), indicating deterioration of regulatory feedbacks. Besides, a decrease of coherence between MAP and PI in low-frequency range was observed after suspension in both intact and sympathectomized rats, indicating alteration of non-sympathetic cardiovascular control mechanisms.

Effect of tail suspension on haemodynamics in intact and sympathectomized rats

The effect of a 2-week tail suspension on mean arterial pressure (MAP) and pulse interval (PI) was studied in conscious chronically instrumented intact and sympathectomized rats. Sympathectomy was induced by 6-hydroxydopamine (100 mg x kg(-1), i.v.), injected 1 day before, and on days 5 and 10 of suspension. During suspension the intact rats had the same levels of MAP and PI as the intact controls. After release from suspension their MAP did not change: PI decreased (by 9%), but only for 1 h. Sympathectomy augmented the haemodynamic changes after release from suspension: tachycardia (10%) and hypotension (19%) were observed during the entire recording period (2 h). Therefore, in rats, post-suspension hypotension becomes apparent only after elimination of sympathetic influences. In spite of unaltered systemic parameters, intact post-suspension rats showed diminished responses to intravenous administration of tyramine (100 microg x kg(-1)) and phenylephrine (1-2 microg x kg(-1)). In addition, they showed augmented haemodynamic changes associated with natural behaviour. The increase of MAP and the decrease of PI on transition from rest to movement were more pronounced in the intact post-suspension rats than in the control rats (MAP 8.3% vs 4.5%, PI 15% vs 9%). In control rats the spectrum power density of low-frequency (0.0195-0.25 Hz) MAP fluctuations depended only weakly on behavioural activity, whereas in post-suspension intact rats it was profoundly augmented during movements (by 170%). Since the rapid adjustment of haemodynamics to behavioural activity is controlled by the sympathetic nervous system, the unbalanced condition of the cardiovascular system after suspension may reflect an altered sympathetic nerve control of the circulation.

The neurogenic constrictor response of isolated rat saphenous artery is reduced after 2-week tail suspension

Under real or simulated microgravity conditions the control of arterial vascular tone is greatly disturbed. The low arterial vessel reactivity to sympathetic influences may be the cause of an increase in flow in hind limb skeletal muscles in tail-suspended (TS) rats. Our previous experiments with constant pressure perfusion of rat hind limb demonstrated the reduced vasoconstrictor responses to sympathetic nerve stimulation in TS rats. Responses to exogenous noradrenaline depended on the perfusion conditions. It is known that the vessels of various branching orders noticeably differ in nerve density and in sensitivity to vasoconstrictor agonists. So under neurogenic or exogenous noradrenaline influences the vascular resistance may be increased at different levels of vascular bed, thus making the data analysis seriously complicated. This uncertainty may be overcome by investigation of a single vessel isolated from hind limb vascular bed. The saphenous artery, a resistance artery with dense innervation, is a very convenient object for this purpose. Thus, this study was aimed at comparing the effects of 2-week tail suspension upon the constrictor responses of isolated saphenous artery to neurogenic and exogenous noradrenaline stimuli in rats.

Regulation of hemodynamics in sympathectomized rats after adaptation to tail suspension

The organism adapts to actual or simulated microgravity by complex interactions of nervous, hormonal and local control mechanisms. Sympathetic nervous system is believed to play the leading role in this adaptation (Robertson et al. 1994). However, this conclusion seems to be rather deductive, as it has not been proved directly. Chronic sympathectomy provides a straightforward approach to this problem. We have studied the role of sympathetic nervous system in adaptation of cardiovascular system to simulated microgravity by tail suspension in intact and sympathectomized rats.

Dynamics of blood pressure and pulse interval duration in rats after 14 day suspension

At present, the pronounced changes in cardiovascular system observed in microgravity and on returning to 1 g are mostly attributed to the regulatory disturbances. The tail suspension model is used to simulate the effects of microgravity on muscle, bone and, on cardiovascular system of rats. Having in mind all limitations of this method, we decided to use it for analysis of the acute effects of cessation of tail suspension on regulation of cardiovascular system in rats.

Effect of 3-week suspension on sympathetic vasoconstrictor response in rat

One of the main problems arising after gravitational unloading is an orthostatic intolerance leading to failure in supporting the upright posture and performing natural locomotion. Among a number of causes for the orthostatic intolerance the decreased circulating blood volume, increased venous distention, alterations in microcirculation, loss of muscular tonus, and regulatory disturbances could be mentioned. The later cause has been intensively studied recently. The aim of the present study is to examine the alterations induced by simulated gravitational unloading in the reaction of resistance vessels of isolated hind limb to the sympathetic stimuli in rats.