Log LF Research Articles

Effects of Mental Stress and Slow Breathing on Autonomic Control of Arterial Blood Pressure (ABP) in Young Normotensives with Hypertensive Parents (FH+) Relative to Those with Normotensive Parents (FH‐)

Young normotensive (FH+) have greater risk of hypertension than FH-. Whether mental stress differentially affects autonomic control of ABP in young normotensive FH+ relative to FH- and whether slow breathing might reduce risk of hypertension in FH+ is not known.In 25 FH- and 23 FH+ (aged 18-25 years), we recorded ABP, ECG and respiratory frequency (Rf); Stroke volume (SV), cardiac output (CO) and total peripheral resistance (TPR) were derived from the pulse contour. The vagal component of baroreflex sensitivity (BRS) was tested by the sequence method at rest and during mental stress (Colour Stroop test). The vagosympathetic BRS was recorded as change in R-R interval evoked by the depressor response to stand from squat before and 0, 3, 6 min after mental stress. Heart rate variability (HRV) was analysed in time- and frequency-domains. Comparisons within and between FH- and FH+ were made by paired and unpaired t-tests. FH- and FH+ had similar mean ABP (ABP: 85±0.8 vs 88±1.8 mmHg) and Rf (15.9±0.6 vs 15.9±0.5 breaths/min) at rest. Mental stress increased ABP, HR, and Rf in both FH+ and FH-, but the increase in ABP was greater in FH+ (ABP: 82.0±2.0 to 109.0±4.0*; 78.3±1.8 to 98.5±2.2*†mmHg, respectively, *: P<0.05 within group, †: P<0.05 between groups). Further, CO increased in FH- only (FH-: 4.9±0.2 to 5.6±0.3*; FH+: 4.9±0.2 to 5.2±0.4 L/min), whereas TPR increased in FH+ only (FH-: 1.0±0.04 to 1.2±0.1; FH+: 1.1±0.1 to 1.8±0.3* units). Meanwhile, in the frequency domain, sympathetic indices increased and vagal indices of HRV decreased (LF increased, HF fell; LF/HF increased) in both FH- and FH+; vagal indices also decreased in the time domain (RMSSD: 60.5±7.2 to 46.8±4.8ms*; 65.8±7.9 to 47.7±6.7ms*, respectively). BRS decreased in mental stress during up- and down-sequences in SP in both FH- and FH+. Further, following the stress test, tachycardic BRS during squat to stand was preserved in FH+, but attenuated in FH- (0.50±0.05 to 0.29±0.07*; 0.50±0.05 to 0.47±0.07ms/mmHg respectively). Considering slow breathing, ABP decreased in both FH- and FH+ (ABP: 78.3±1.8 to 76.1±2.0*; 82.0±2.0 to 79.4±1.9*mmHg, respectively). Further, BRS during up-sequences increased in FH+ (0.98±0.09 to 1.2±0.09*ms/mmHg) to equal that of FH- (1.16±0.06 to 1.2±0.07ms/mmHg), while vagal indices of HRV increased and sympathetic indices decreased in FH- and FH+ (Log HF:1.7±0.03 to 1.93±0.01*; 1.7±0.03 to 1.94.01*, Log LF: 0.78±0.06 to 0.38±0.08*; 0.8±0.05 to 0.28±0.06*ms2). These findings suggest that young normotensive FH+ show an exaggerated pressor response to mental stress relative to FH- that is associated with enhanced sympathetic vasoconstriction in FH+. Further, although the vagal component of HRV and BRS was attenuated during mental stress in FH+ and FH-, the persistent tachycardic baroreflex for several minutes after stress in FH+ but not FH- suggests further baroreflex sympathetic activation can still occur in FH+. Such autonomic disturbances would be expected to increase future risk of hypertension in FH+. However, our findings with slow breathing suggest regular slow breathing may reduce this risk in FH+ by increasing cardiac vagal tone and reducing sympathetic tone.

LONG-TERM EFFECT OF ANTIHYPERTENSIVE AGENTS ON THE NEURAL BAROREFLEX SENSITIVITY-A SUBSTUDY OF THE PARIS PROSPECTIVE STUDY III

Objective: The baroreflex is a crucial mechanism regulating moment-to-moment blood pressure (BP) to ensure appropriate flow and pressure to the brain and other organs. All antihypertensive treatments, because of their BP lowering effect, interact with the autonomic nervous system by stimulating the sympathetic response. In addition, specific drugs may further interact with the BRS because of their specific mode of action. Whether antihypertensive agents have remnant effect is still unknown. Design and method: In the Paris Prospective Study III, spontaneous baroreflex, carotid stiffness and pharmacological drugs intake were available in 7967 adults (mean age of 60 ± 6 years, 62% men). The neural component of the baroreflex sensitivity (nBRS) was obtained with a cross-spectral analysis of variations in carotid distention rate and R-R intervals. Individuals with a BP lowering medication (BP-treated) were paired to non-BP treated individuals (controls) with similar cardiovascular comorbidities using a propensity score matching procedure (n = 1182 pairs). Results: Sympathetic activity was higher in the BP-treated group compared to their matched-controls, as shown by the increased spectral power of distention rate in the low frequency band (log LF distrate: 4.106 ± 0.530 vs 4.055 ± 0.514, p = 0.018). Amongst pharmacological classes of BP lowering agents, only agents acting on the angiotensin system (ACEi-ARB) were associated with nBRS. Compared to their matched controls (n = 331 pairs), ACEi-ARB users had lower nBRS (2.79 ± 0.66 (ln) vs. 2.90 ± 0.62 (ln), p = 0.03). After adjustment for carotid stiffness (stdbeta = 0.25, p &lt; 0.001) and systolic pressure (stdbeta = -0.20, p &lt; 0.001), ACEi-ARB remained significantly associated with nBRS (stdbeta = -0.09, p = 0.025). Conclusions: In this community-based population study, antihypertensive treatments induced activation of the autonomic nervous system independently of cardiovascular comorbidities. Taken as a whole, BP treatments did not have any effect on the neural component of the baroreflex loop, with the exception of ACEi-ARB which were negatively associated with nBRS. This effect was independent of BP and stiffness, which may suggest an inhibition of sympathetic activity by ACEi-ARB.

Evaluation of the Long-Term Changes in Fatigue of Cancer Survivors Who Received Outpatient Chemotherapy in the Area Affected by the Great East Japan Earthquake

Objective: The aim of the study is to evaluate the long-term changes in fatigue of cancer patients receiving outpatient chemotherapy after a disaster such as the Great Earthquake. Methods: From 2012 to 2014, we measured subjective fatigue, autonomic function, and physical activity with reference to the criteria for chronic fatigue syndrome. Results: The participants were 13, 9 males (69.2%) and 4 females (30.8%). The most common cancer among the participants was lung cancer 4 patients (30.8%). In 2012, eight patients (61.6%) received anti-cancer drugs and three (23.0%) received the drug by intravenous drip and oral administration. Physical fatigue (p = 0.004), mental fatigue (p = 0.002), comprehensive fatigue (p = 0.012), and comprehensive evaluations (p = 0.032) were significantly different. Significant differences in the autonomic nervous function were observed during the three years from 2012 to 2014 (log LF [p = 0.017], log HF [p = 0.023] and log LF/HF [p = 0.039]). Similar to Subjective fatigue, Significant differences in physical activity were observed during the three years from 2012 to 2014 (DA [p = 0.042], TST [p = 0.037], SE [p = 0.018], AW [p = 0.023] and Naps [p = 0.014]). Conclusions: The participants fatigue worsened at one time, but showed improvement over time. In the event of an emergency such as a disaster, it is necessary to evaluate the physical and mental condition based on objective indicators of cancer patients receiving anti-cancer drug treatment and provide nursing support.

Effects of judo training upon body composition, autonomic function, and cardiorespiratory fitness in overweight or obese children aged 8- to 13 years

ABSTRACT Physical training is recommended for obese paediatric populations. We investigated the effects of recreational judo training (JT) upon body composition and distribution, cardiorespiratory fitness, and heart rate variability (HRV) in overweight or obese children. A controlled trial (RBR-9d94td) was conducted with 35 children (8–13 years) assigned into groups according to their body mass index (BMI): eutrophic (EU; n = 15; z-BMI ≤ +l and ≥ −2) and overweight or obese (OB; n = 20; z-BMI > +1 and ≤ +3). The 12-week JT included 60-min sessions performed 2 times/week at 65–75% maximal heart rate (HR). BMI, waist circumference, blood pressure, HRV, peak oxygen uptake (VO2peak), gas exchange threshold (GET), and body fractioning were assessed. Significant reductions in OB (P < 0.05) occurred for whole body and trunk fat (~3%), trunk/limb fat-ratio (~4%), resting HR (~3%), and sympathovagal balance (log LF:HF, ~85%). Increases (P < 0.05) occurred in lean mass (~8%), parasympathetic modulation (log HF, ~4%), VO2peak (~5-10%), and VO2 (~15%), speed (~10%) and slope (~13%) at GET. Markers of cardiorespiratory fitness (relative VO2, slope and speed at GET) in OB approached EU after JT. In conclusion, a relatively short JT intervention to improved body composition, autonomic modulation, and physical fitness in obese children.

Mucosal lactoferrin response to genital tract infections is associated with iron and nutritional biomarkers in young Burkinab\xe9 women

Background/ObjectivesThe iron-binding affinity of vaginal lactoferrin (Lf) reduces iron available to genital pathogens. We describe host reproductive, nutritional, infection and iron biomarker profiles affecting vaginal Lf concentration in young nulliparous and primigravid women in Burkina Faso.Subjects/MethodsVaginal eluates from women who had participated in a randomized, controlled periconceptional iron supplementation trial were used to measure Lf using a competitive double-sandwich ELISA. For this analysis samples from both trial arms were combined and pregnant and non-pregnant cohorts compared. Following randomization Lf was measured after 18 months (end assessment) for women remaining non-pregnant, and at two antenatal visits for those becoming pregnant. Associations between log Lf levels and demographic, anthropometric, infection and iron biomarker variables were assessed using linear mixed models.ResultsLf samples were available for 712 non-pregnant women at end assessment and for 303 women seen at an antenatal visit. Lf concentrations of pregnant women were comparable to those of non-pregnant, sexually active women. Lf concentration increased with mid-upper-arm circumference, (P = 0.047), body mass index (P = 0.018), Trichomonas vaginalis (P < 0.001) infection, bacterial vaginosis (P < 0.001), serum C-reactive protein (P = 0.048) and microbiota community state types III/IV. Adjusted Lf concentration was positively associated with serum hepcidin (P = 0.047), serum ferritin (P = 0.018) and total body iron stores (P = 0.042). There was evidence that some women maintained persistently high or low Lf concentrations from before, and through, pregnancy.ConclusionLf concentrations increased with genital infection, higher BMI, MUAC, body iron stores and hepcidin, suggesting nutritional and iron status influence homeostatic mechanisms controlling vaginal Lf responses.

PP.17.30

Objective: Recently, it has been revealed that orthostatic hypotension (OH) is a risk factor associated with the onset of cardiovascular disease (CVD). Increased arterial stiffness and autonomic nervous dysfunction is considered to be one of the important causes of OH. However, there are few reports of the association between arterial stiffness, autonomic nervous function and OH. Therefore, we evaluated the interconnectedness of arterial stiffness, autonomic nervous function and OH in patients with atherosclerosis risk factors. Design and method: We studied 652 patients having atherosclerosis risk factors such as hypertension, dyslipidemia and diabetes mellitus. Cardio-ankle vascular index (CAVI) was measured as an index of arterial stiffness. Blood pressure and heart rate measurements were performed during sit-to-stand orthostatic stress test to evaluate the heart rate variability (HRV) and orthostatic change in blood pressure and heart rate. Results: A significant negative correlation was found between orthostatic systolic blood pressure (SBP) change and CAVI (P < 0.001). LogLF (low frequency component) at all phase (rest phase, initial orthostatic phase and delayed orthostatic phase) and logHF (high frequency component) at all phase (except delayed orthostatic phase) had significant negative correlation with age. LogLF at all phase and logHF at all phase (except resting phase) had significant positive correlation with initial orthostatic SBP change. CAVI had a significant negative correlation with logLF at all phase and logHF at all phase (except delayed orthostatic phase). In the multiple regression analysis, initial orthostatic SBP change had a significant correlation with CAVI, logLF and logHF while orthostatic stress test, independent of age and gender (CAVI; P < 0.001, log LF at initial orthostatic phase; P = 0.020, logLF at delayed orthostatic phase; P = 0.026 and logHF at delayed orthostatic phase; P = 0.004). Conclusions: In patients with atherosclerosis risk factor, increased arterial stiffness and decreased HRV independently associated with orthostatic blood pressure decrease regardless of age and gender while their interrelationship exists. Decreased HRV caused by decreased baroreflex sensitivity while orthostatic stress may be one of the important mechanisms that links OH with CVD.

Autonomic Dysfunction in Chronic Fatigue Syndrome

Symptoms of autonomic dysfunction are one of the characteristic features of the clinical condition known as chronic fatigue syndrome (CFS). In this study we examined the autonomic nerve functions in 1,099 patients with CFS and in 361 normal healthy controls. The autonomic nerve functions were studied in terms of heart rate variability and spectral analysis, and by using the maximal Lyapunov exponent (MLE) and chaotic analysis. The heart rate variability analysis revealed that both the logarithmic low-frequency power (Log LF) and logarithmic high-frequency power (Log HF) were reduced significantly with age in healthy subjects (p < 0.005). When we compared these parameters between the CFS patients and healthy controls according to age groups, there was no significant difference in Log LF between CFS and control except in the case of the 40's age group. However, Log HF decreased significantly in moderate and severe fatigue CFS groups in all age groups. All of the severe fatigue CFS age groups had a significant increase in the ratio of Log LF/HF as compared with that of the healthy controls. When we studied the change in these power values during sleep as compared with that during awake time, the HF power rose 3.03-fold in the controls and 1.86-fold in the CFS group during sleep as compared with that during the awake time; and this difference in fold increase during sleep between the CFS and control groups was significant (p < 0.05). Furthermore, the MLE for both the moderate and severe fatigue CFS groups was decreased significantly as compared with that of the healthy control group (p < 0.01). It is well known that autonomic nervous function differs greatly in individuals, but our present large research study indicates that there is no doubt that parasympathetic nervous dysfunction is involved in the pathophysiology of CFS patients with severe fatigue. We incorporated the evaluation of autonomic function into the Japanese CFS diagnostic criteria in 2012, because this evaluation might be a useful objective diagnostic tool for CFS.

Evaluation of sleep quality by spectral electroencephalographic entropy using nasal continuous positive airway pressure recorded by a portable biosignal measuring device

s from The Japanese Journal The Autonomic Nervous System #1 Evaluation of sleep quality by spectral electroencephalographic entropy using nasal continuous positive airway pressure recorded by a portable biosignal measuring device Noriko Ohisa, Hiromasa Ogawa, Toshiya Irokawa, Hajime Kurosawa, Katsumi Yoshida Clinical Laboratory Department, Tohoku University Hospital, Sendai 980-8574, Japan Health Administration Center, Tohoku University, Japan Medical Technology Department, Tohoku University School of Health Sciences, Japan Polysomnography is the gold standard for the diagnosis of obstructive sleep apnea/hypopnea syndrome (OSAHS). However, the procedure is very expensive and much time is required for analyzing polysomnography repeatedly. Here we present data by electroencephalographic (EEG) spectral entropy, calculated using MemCalc, used as an index for evaluating sleep quality. EEG spectral entropy was evaluated and was compared to the results of polysomnography. Twelve subjects with obstructive sleep apnea/hypopnea syndrome participated in this study. They were treated with nasal continuous positive airway pressure (CPAP). The EEG was recorded by means of a portable biosignal measuring (PBSM) device and polysomnography was recorded using Alice III, during a 10-hour period from 20:00 to 6:00. Spectral entropy was aligned with the sleep stages extracted manually from the polysomnography recordings, and was compared in subjects with or without treatment with continuous positive airway pressure. There was a statistically significant decrease in spectral entropy (from −1.369 to −1.206; pb0.05) when the subjects were treated with continuous positive airway pressure compared to when the subjects had only received a pretreatment with continuous positive airway pressure. In 10 subjects treated with continuous positive airway pressure there was a cut-off at −1.313 for the reduction of negative values of spectral entropy. We conclude that the spectral entropy, calculated using MemCalc, appears to be a viable alternative index for evaluating sleep quality in positive airway pressure treatment. (The Autonomic Nervous System, 47: 271–276, 2010) doi:10.1016/j.autneu.2011.08.010 #2 Aging and gender effects on heart rate variability in healthy Japanese elderly Akira Katagiri, Masato Asahina, Yoshikatsu Fujinuma, Yuichi Akaogi, Yoshitaka Yamanaka, Takeshi Fukushima, Hitoshi Shinotou, Takamichi Hattori, Toshiomi Asahi Department of Neurology, Chiba University School of Medicine, Chiba 260-8670, Japan Asahi Neurology and Rehabilitation Hospital, Chiba 270-0022, Japan The aim of this study was to evaluate the effects of aging and gender on frequency-domain indexes of heart rate variability (HRV) in healthy Japanese elderly. The subjects were 45 healthy Japanese aged 65 or over (28 men and 15 women, aged 73.4+5.2 years) who were undergoing electrocardiography. R–R intervals of 300 beats were analyzed spectrally into low frequency (LF, 0.04–0.15 Hz) and high-frequency (HF, 0.15–0.4 Hz) components, with normalized unit LF and HF (nuLF and nuHF), and LF/HF obtained. The HRV parameter means were: LF 161±226 ms, HF 130± 174 ms, LF/HF 2.3±3.3, nuLF 53.0±20.5% and nuHF 39.5±16.8%. LF, HF and LF/HF were logarithmically distributed, and converted. Log LF was 1.91±0.52, log HF 1.78±0.56 and log LF/HF 0.13±0.44. No significant correlations were seen between HRV parameters and age, or between HRV and gender. We conclude that when evaluating HRV parameters in the healthy Japanese elderly, the HRV decrease found in elderly subjects may be more difficult to explain than when found in the young. (The Autonomic Nervous System, 47: 381–385, 2010) doi:10.1016/j.autneu.2011.08.011 #3 Computer-simulated detection of true SSR waveforms on the back of the hand Hiroko Mitani, Yoji Ishiyama Department of Clinical Physiology and Medical Applied Engineering, School of Health Sciences, Kyorin University, Tokyo 192-8508, Japan To infer true sympathetic skin response (SSR) waveforms on the dorsal surface of the hand, we studied SSR potential polarity and

Aging and gender effects on heart rate variability in healthy Japanese elderly

s from The Japanese Journal The Autonomic Nervous System #1 Evaluation of sleep quality by spectral electroencephalographic entropy using nasal continuous positive airway pressure recorded by a portable biosignal measuring device Noriko Ohisa, Hiromasa Ogawa, Toshiya Irokawa, Hajime Kurosawa, Katsumi Yoshida Clinical Laboratory Department, Tohoku University Hospital, Sendai 980-8574, Japan Health Administration Center, Tohoku University, Japan Medical Technology Department, Tohoku University School of Health Sciences, Japan Polysomnography is the gold standard for the diagnosis of obstructive sleep apnea/hypopnea syndrome (OSAHS). However, the procedure is very expensive and much time is required for analyzing polysomnography repeatedly. Here we present data by electroencephalographic (EEG) spectral entropy, calculated using MemCalc, used as an index for evaluating sleep quality. EEG spectral entropy was evaluated and was compared to the results of polysomnography. Twelve subjects with obstructive sleep apnea/hypopnea syndrome participated in this study. They were treated with nasal continuous positive airway pressure (CPAP). The EEG was recorded by means of a portable biosignal measuring (PBSM) device and polysomnography was recorded using Alice III, during a 10-hour period from 20:00 to 6:00. Spectral entropy was aligned with the sleep stages extracted manually from the polysomnography recordings, and was compared in subjects with or without treatment with continuous positive airway pressure. There was a statistically significant decrease in spectral entropy (from −1.369 to −1.206; pb0.05) when the subjects were treated with continuous positive airway pressure compared to when the subjects had only received a pretreatment with continuous positive airway pressure. In 10 subjects treated with continuous positive airway pressure there was a cut-off at −1.313 for the reduction of negative values of spectral entropy. We conclude that the spectral entropy, calculated using MemCalc, appears to be a viable alternative index for evaluating sleep quality in positive airway pressure treatment. (The Autonomic Nervous System, 47: 271–276, 2010) doi:10.1016/j.autneu.2011.08.010 #2 Aging and gender effects on heart rate variability in healthy Japanese elderly Akira Katagiri, Masato Asahina, Yoshikatsu Fujinuma, Yuichi Akaogi, Yoshitaka Yamanaka, Takeshi Fukushima, Hitoshi Shinotou, Takamichi Hattori, Toshiomi Asahi Department of Neurology, Chiba University School of Medicine, Chiba 260-8670, Japan Asahi Neurology and Rehabilitation Hospital, Chiba 270-0022, Japan The aim of this study was to evaluate the effects of aging and gender on frequency-domain indexes of heart rate variability (HRV) in healthy Japanese elderly. The subjects were 45 healthy Japanese aged 65 or over (28 men and 15 women, aged 73.4+5.2 years) who were undergoing electrocardiography. R–R intervals of 300 beats were analyzed spectrally into low frequency (LF, 0.04–0.15 Hz) and high-frequency (HF, 0.15–0.4 Hz) components, with normalized unit LF and HF (nuLF and nuHF), and LF/HF obtained. The HRV parameter means were: LF 161±226 ms, HF 130± 174 ms, LF/HF 2.3±3.3, nuLF 53.0±20.5% and nuHF 39.5±16.8%. LF, HF and LF/HF were logarithmically distributed, and converted. Log LF was 1.91±0.52, log HF 1.78±0.56 and log LF/HF 0.13±0.44. No significant correlations were seen between HRV parameters and age, or between HRV and gender. We conclude that when evaluating HRV parameters in the healthy Japanese elderly, the HRV decrease found in elderly subjects may be more difficult to explain than when found in the young. (The Autonomic Nervous System, 47: 381–385, 2010) doi:10.1016/j.autneu.2011.08.011 #3 Computer-simulated detection of true SSR waveforms on the back of the hand Hiroko Mitani, Yoji Ishiyama Department of Clinical Physiology and Medical Applied Engineering, School of Health Sciences, Kyorin University, Tokyo 192-8508, Japan To infer true sympathetic skin response (SSR) waveforms on the dorsal surface of the hand, we studied SSR potential polarity and

A study on the age, growth and reproduction of Aspius vorax (Heckel, 1843) (Cyprinidae) in Atatürk Dam Lake (Euphrates River), Turkey

In this study, the age, growth and reproduction characteristics of Aspius vorax, which were caught from Ataturk Dam Lake (Euphrates River) between September 2007 and August 2008 were determined. The age composition of the specimens ranged between II and IX age groups. The observed sex ratio was 1:1.75 (females/males). The fork length and weight of the individuals that were examined ranged from 184 to 863 mm and from 54g to 4317g, respectively. The relationship of fork length (LF) and scale radius (S) was estimated as: LF=-95.6669+172.254 S, (r2= 0.669). L∞ values were calculated to be 158.36 cm for females and 218.47 for males. Length - weight relationships were Log W =-3.4242+2.4297 Log LF (r2=0.8686) for females, and Log W =-4.7247+2.9051 Log LF (r2=0.9549) for males. Mean somatic condition of females and males were estimated as 1.069 and 1.062, respectively. The highest values of the somatic condition were determined in the November for females (K=1.23) and in the September and October (K=1.13) for males. Males matured during their third year of life in the studied samples, but due to lacking of young female specimens, the first maturity age for female was not determined. However, all those females examined at age 4 and over were seen to reach mature.

Insulin resistance and circadian rhythm of cardiac autonomic modulation

BackgroundInsulin resistance (IR) has been associated with cardiovascular diseases (CVD). Heart rate variability (HRV), an index of cardiac autonomic modulation (CAM), is also associated with CVD mortality and CVD morbidity. Currently, there are limited data about the impairment of IR on the circadian pattern of CAM. Therefore, we conducted this investigation to exam the association between IR and the circadian oscillations of CAM in a community-dwelling middle-aged sample.MethodHomeostasis models of IR (HOMA-IR), insulin, and glucose were used to assess IR. CAM was measured by HRV analysis from a 24-hour electrocardiogram. Two stage modeling was used in the analysis. In stage one, for each individual we fit a cosine periodic model based on the 48 segments of HRV data. We obtained three individual-level cosine parameters that quantity the circadian pattern: mean (M), measures the overall average of a HRV index; amplitude (Â), measures the amplitude of the oscillation of a HRV index; and acrophase time (θ), measures the timing of the highest oscillation. At the second stage, we used a random-effects-meta-analysis to summarize the effects of IR variables on the three circadian parameters of HRV indices obtained in stage one of the analysis.ResultsIn persons without type diabetes, the multivariate adjusted β (SE) of log HOMA-IR and M variable for HRV were -0.251 (0.093), -0.245 (0.078), -0.19 (0.06), -4.89 (1.76), -3.35 (1.31), and 2.14 (0.995), for log HF, log LF, log VLF, SDNN, RMSSD and HR, respectively (all P < 0.05). None of the IR variables were significantly associated with  or θ of the HRV indices. However, in eight type 2 diabetics, the magnitude of effect due to higher HOMA-IR on M, Â, and θ are much larger.ConclusionElevated IR, among non-diabetics significantly impairs the overall mean levels of CAM. However, the  or θ of CAM were not significantly affected by IR, suggesting that the circadian mechanisms of CAM are not impaired. However, among persons with type 2 diabetes, a group clinically has more severe form of IR, the adverse effects of increased IR on all three HRV circadian parameters are much larger.

Effects of Gender and Aging on Differential Autonomic Responses to Orthostatic Maneuvers

There are gender differences in heart rate and blood pressure response to postural change. Also, normal aging is often associated with diminished cardiac autonomic modulation during postural change from supine to upright position. Nevertheless, the exact mechanisms of these physiological alterations are not entirely understood. A total of 362 volunteers (206 females, age range: 10-88 years) underwent continuous, noninvasive, beat-to-beat blood pressure and ECG recordings in supine and upright position. To calculate spontaneous baroreflex sensitivity (BRS), blood pressure and RR interval fluctuations were reconstructed using the time-domain sequential technique. Furthermore, mean systolic and diastolic blood pressure, mean heart rate, and frequency-domain parameters of heart rate variability (low-frequency power [LF], low-frequency power in normalized units [LFn] high-frequency power [HF], high-frequency power in normalized units [HFn], low-/high-frequency ratio [LF/HF], and total power [TP]) were analyzed in both supine and standing positions. To investigate age-related differences, subjects were divided into four equally sized groups (quartile l: 10-33 years; ll: 34-42 years; III: 43-57 years; and lV: 58-88 years), as well as decades (l: 10-19 years; ll: 20-29 years; lll: 30-39 years; lV: 40-49 years; V: 50-59 years; Vl: 60-69 years; Vll: >or= 70 years). A continuous decline in BRS, LF, HF, and TP was observed with increasing age in both male and female subjects, regardless of posture. Gender comparison showed significantly higher values of LF (supine P < 0.001; upright P < 0.05), LFn (supine P < 0.001; upright P < 0.01), and TP (supine P < 0.05; upright P < 0.05) in men than women in supine and standing positions. HF revealed no gender difference and HFn (supine P < 0.001; upright P < 0.05) was larger in women. Log BRS correlated well with log LF and log HF in both supine and standing positions. There are significant differences in postural cardiac autonomic modulation between men and women, and the degree of autonomic response to orthostatic maneuvers varies with normal aging. These results may explain gender- and age-related differences in orthostatic tolerance.

Heart rate turbulence in adults with repaired tetralogy of Fallot

Background Tetralogy of Fallot (ToF) patients face an increased risk of sudden cardiac death late after repair. Heart rate turbulence (HRT) indices are well-known predictors of sudden cardiac death. We aimed to estimate whether HRT is impaired in repaired ToF patients compared to healthy controls and relate those HRT parameters to already recognized prognostic markers. Methods Continuous ECG recordings were performed in 19 patients late after ToF repair (36.3 ± 12.4 years, 26.6 ± 7.1 years after repair) and 20 age-matched healthy controls (40.8 ± 8.1 years). Turbulence slope (TS) and onset (TO), frequency and time domain heart rate variability parameters and QRS duration were estimated. Volumes of the right (RV) and left ventricle (LV) and ejection fraction (EF) were assessed by cardiovascular magnetic resonance imaging. Cardiopulmonary exercise testing was used to estimate peak oxygen consumption (VO 2) and VE/VCO 2 slope. Results TS (15.95 ± 9.41 vs 28.73 ± 12.24 ms/RRI, p = 0.0007) and TO (− 0.98 ± 2.06% vs − 3.45 ± 3.25%, p = 0.007) were found to be significantly different between ToF patients and controls. TO correlated with LVEF ( r = 0.47, p < 0.05), LVSVi ( r = 0.50, p = 0.03), RVEF ( r = 0.53, p = 0.02), peak VO 2 ( r = 0.50, p = 0.05), VE/VCO 2 slope ( r = − 0.55, p = 0.03) and with heart rate variability frequency domain indices (log LF, r = 0.47, p = 0.04, log HF, r = 0.56, p = 0.01). Conclusion HRT indices are impaired in ToF patients late after surgical repair compared to healthy controls and relate to coexisting haemodynamic, ventilatory and autonomic impairment. A clinical prognostic role of HRT may be speculated, which warrants further investigation.

The Distribution of Values of the Hecke L-Functions at 1

Let S2(q) be the set of primitive forms in the space S2(Γ0(q)) of holomorpic Γ0(q)-cusp forms of weight 2. Let f ∈ S2(q) and let Lf(S) be the L-function of f(z). It is proved that the set {log Lf(1), f ∈ S2(q)} has a limit distribution function. The rate of convergence to this limit function is estimated. Bibliography: 10 titles.

A characterization of Hardy-Orlicz spaces on planar domains

In the paper we prove that for a wide class of bounded domains $D$ in $\mathbb {C}$, a holomorphic function $f$ is in the Hardy-Orlicz space ${H_\phi }(D)$ if and only if \[ \iint _D {\delta (z)\phi ''(\log |f(z)|)\frac {{|f’(z){|^2}}} {{|f(z){|^2}}}dx dy < \infty ,}\] where $\delta (z)$ denotes the distance from $z$ to the boundary of $D$ and $\phi$ is a strongly convex function on $( - \infty ,\infty )$ for which $\phi ''(t)$ exists for all $t$.

Riemann map and holomorphic dynamics

f ( F r A ) = F r A and ~ f " ( U c ~ c l A ) = F r A (i.e. FrA repels to the side of A). n=O (Assume that U is always sufficiently small so that f has no singularities in U c~ A.) Let R: D Z ~ A be a Riemann map (a conformal homeomorphism) of the unit disc onto A. Then there exists a holomorphic extension g of R l o f o R to a neighbourhood of S 1 and gls, happens to be an expanding map, i.e. there exists n > 0 such that for every z ~ S l , l (g") ' (z)[>l. (Although the proofs are straightforward, we include them for sceptics in the last section, Sect. 7, together with a remark about examples of A and f satisfying the above assumptions.) Denote by _gthe non-tangential limit of R and by ~ K = S 1 the domain where it exists. Denote by ~IJl (g) the space of all Borel, probability g-invariant, ergodic, positive entropy measures on S 1. It is known (see [P]) that for every/~ EgJI (g), K exists ~almost everywhere, so the f-invariant measure R. (/~) on FrA can be considered. The functions log[g'[, log lf ' [ are /z-, respectively R,(/0-integrable (see 1.5). Denote these integrals by )~u (g), g~.(~)(f)(In this paper we consider derivatives with respect to the Riemannian metric on $2.) Define the Hausdorff dimension of any probability measure v:

On the geometric means of entire functions of several complex variables

Let f(z, z.,) be an entire function of the n (? 2) complex variables Z1 ... . Zn, holomorphic for Izt I rt, t= 1 ... , n. We have considered the case of only two complex variables for simplicity. Recently many authors have defined the arithmetic means of the function lf(zl, z2)I and have investigated their properties. In the present paper, the geometric means of the function lf(zl, Z2)t have been defined and the asymptotic behavior of certain growth indicators for entire functions of several complex variables have been studied and the results are given in the form of theorems. 1. Let f(zlg .. * Zn) = ki.. knZll* *nt kl ,...,kn> be an entire function of the n (> 2) complex variables z1, ..., ,Zn, holomorphic for $ztl rt, t= 1, .. ., n. Let us denote the maximum modulus of the function f(ZlX* .. X Zn) as M(rl, ... rn) = max if(z1, ..., zZn) (t= 1, .. , n). lztl <rt Here we consider the case of only two complex variables for simplicity. The results can easily be extended to several complex variables. The geometric mean of If(z1, z2)1 for Iztj ? rt (t= 1, 2) has been defined as [4] 1 rzz rzz (1.1) G(r1, r2) = exp {(2_)2 J J log lf(rlei0i, r2ei02)1 dO1 d02}. Further, let us define 4 (k+ 1) 2 r1 r2 loG(, dx xi (1.2) gk(rl, r2) = exp ( )k J (xx2)k log G(xl 1 2 where k is any positive number. Received by the editors September 20, 1968 and, in revised form, March 25, 1970. AMS 1969 Subject Classifications. Primary 3205, 3210; Secondary 3217.