Plasma oxidative state induced by exercise in young heat-not-burn cigarette users.

INTRODUCTION: Oxidative state, a risk factor for several diseases, is increased by habitual conventional cigarette (CC) smoking. Reports have demonstrated that heat-not-burn cigarettes (HNBC), which have recently become popular among smokers, generate less oxidative state than CC in smokers with a long smoking history. However, no previous study has examined oxidative state in young HNBC users. Previously, we reported that exercise induces a greater oxidative state in young CC smokers than in never-smokers of similar age, but there was no difference in resting oxidative state. This study aimed to clarify the resting and exercise-induced oxidative states in young HNBC users, compared with those in never-smokers and CC users of similar age. METHODS: Healthy young never-smokers, HNBC users, and CC users were recruited, and they underwent the Wingate anaerobic test. Blood samples were collected before and after exercise, and the plasma hydroperoxide concentration, a marker of oxidative state, was measured. RESULTS: No significant differences in pre-exercise plasma hydroperoxide concentrations were detected among never-smokers, HNBC users, and CC users (n = 10 each). Plasma hydroperoxide concentration was significantly increased after exercise in all participants. The exercise induced a significant increase in plasma hydroperoxide concentration in HNBC users compared with that in never-smokers (P < .005), but it was significantly decreased compared with that in CC users (P < .01). CONCLUSIONS: The use of HNBC increased exercise-induced plasma oxidative state compared with that in never-smokers, indicating that HNBC may lead to the risk of oxidative damage. IMPLICATIONS: This study, for the first time, reports exercise-induced oxidative state in young heat-not-burn cigarette users compared with never-smokers and conventional cigarette users. The exercise-induced oxidative state in heat-not-burn cigarette users was higher than that in never-smokers and lower than that in conventional cigarette users. Our study suggests that the use of heat-not-burn cigarettes increases the risk of acute oxidative damage.

Cough sound-based estimation of vital capacity via cough peak flow using artificial neural network analysis.

This study presents a novel approach for estimating vital capacity using cough sounds and proposes a neural network-based model that utilizes the reference vital capacity computed using the lambda-mu-sigma method, a conventional approach, and the cough peak flow computed based on the cough sound pressure level as inputs. Additionally, a simplified cough sound input model is developed, with the cough sound pressure level used directly as the input instead of the computed cough peak flow. A total of 56 samples of cough sounds and vital capacities were collected from 31 young and 25 elderly participants. Model performance was evaluated using squared errors, and statistical tests including the Friedman and Holm tests were conducted to compare the squared errors of the different models. The proposed model achieved a significantly smaller squared error (0.052 L2, p < 0.001) than the other models. Subsequently, the proposed model and the cough sound-based estimation model were used to detect whether a participant's vital capacity was lower than the typical lower limit. The proposed model demonstrated a significantly higher area under the receiver operating characteristic curve (0.831, p < 0.001) than the other models. These results highlight the effectiveness of the proposed model for screening decreased vital capacity.

Hochuekkito Combined with Pulmonary Rehabilitation in Apathetic Patients with Chronic Obstructive Pulmonary Disease: A Randomized Controlled Pilot Trial.

The main treatment goals for chronic obstructive pulmonary disease (COPD) are the reduction of its symptoms and future risks. The addition of the traditional herbal medicine Hochuekkito (TJ-41) treatment to pulmonary rehabilitation (PR) has been reported to improve dyspnea and health-related quality of life (HRQOL) in patients with COPD. However, the reason for this improvement is not sufficiently understood. The purpose of the present study was to investigate whether the addition of TJ-41 treatment to PR improves symptoms of apathy, dyspnea, and HRQOL and increases physical activity among apathetic patients with COPD. Apathetic patients with COPD were randomly assigned to receive low-intensity exercise with (TJ-41 group) or without (control group) TJ-41 treatment for 12 weeks. A total of 29.9% of COPD patients had apathetic symptoms without severe depression. After the 12-week treatment, Apathy Scale, Patient Health Questionnaire-9, visual analog scale for dyspnea, and COPD assessment test energy scores decreased significantly in the TJ-41 group (p < 0.05), but not in the control group. Additionally, the total number of steps taken was significantly higher in the TJ-41 group than in the control group. TJ-41 combined with PR may benefit apathetic patients with COPD with respect to apathy, dyspnea, HRQOL, and physical activity, but larger randomized placebo-controlled trials are required to validate the findings because of the small sample size and lack of placebo controls in this study.

Effects of L-arginine on impaired blood fluidity after high-intensity exercise: An in vitro evaluation.

BACKGROUND: Exercise-induced impairment of blood fluidity is considered to be associated with thrombosis development. However, the effects of L-arginine on blood fluidity after exercise remain unclear. OBJECTIVE: We investigated the mechanisms of impaired blood fluidity after high-intensity exercise, and examined whether L-arginine improves exercise-induced blood fluidity impairment in vitro. METHODS: Ten healthy male participants performed 15 minutes of ergometer exercise at 70% of their peak oxygen uptake levels. Blood samples were obtained before and after exercise. L-arginine and NG-monomethyl-L-arginine acetate (L-NMMA)-a nitric oxide (NO) synthase inhibitor-were added to the post-exercise blood samples. Using Kikuchi's microchannel method, we measured the blood passage time, percentage of obstructed microchannels, and the number of adherent white blood cells (WBCs) on the microchannel terrace. RESULTS: Exercise increased the hematocrit levels. The blood passage times, percentage of obstructed microchannels, and the number of adherent WBCs on the microchannel terrace increased after exercise; however, they decreased in a dose-dependent manner after the addition of L-arginine. L-NMMA inhibited the L-arginine-induced decrease in blood passage time. CONCLUSIONS: High-intensity exercise impairs blood fluidity by inducing hemoconcentration along with increasing platelet aggregation and WBC adhesion. The L-arginine-NO pathway improves blood fluidity impairment after high-intensity exercise in vitro.

Twenty-four-hour ambulatory oximetry monitoring in a patient with idiopathic pulmonary fibrosis for assisting in the discharge instruction on activities of daily living: a case report.

[Purpose] Patients with idiopathic pulmonary fibrosis (IPF) often develop remarkable exercise-induced hypoxemia and are hospitalized for management. The pre-discharge management of activities of daily living (ADL) should determine the amount of exercise-induced hypoxemia permitted during daily activities and inform concrete instructions based on these results. This clinical report aimed to promote 24-hour ambulatory oximetry monitoring in a patient with IPF to guide the pre-discharge management of ADL. [Participant and Methods] Our patient was a 67-year-old male with IPF. He was hospitalized and scheduled to be discharged after introduction of home oxygen therapy. Prior to discharge, we conducted a 24-hour ambulatory oximetry monitoring in the patient's home. We administered instructions on ADL based on these results. Furthermore, 1 day after discharge, we monitored his oxygen saturation level during ADL in his home. [Results] During the pre-discharge monitoring, the patient experienced hypoxemia during bathing, with a minimum oxygen saturation (SpO2) level of 87% and SpO2 level of <90% for 14.3% of the time. The patient was instructed on bathing by a physical therapist before discharge; this led to decreased desaturation, as the patient's SpO2 was <90% for 7.7% of the time. [Conclusion] Twenty-four-hour ambulatory oximetry monitoring is effective in guiding the pre-discharge management of ADL in the home with home oxygen therapy for patients with IPF.

Effect of the use of passive body trunk exercise equipment on oxygen consumption and self-efficacy for carrying out exercise in patients with type 2 diabetes.

AIMS/INTRODUCTION: Considering the difficulty in inculcating the habit of exercise among patients with type 2 diabetes, devising an easily maintained means of exercise is preferable. Passive body trunk exercise equipment (PBTE) developed for home use might solve several problems related to exercise therapy, both for patients and clinical staff involved in diabetes treatment; however, its efficacy as a therapeutic exercise device for patients with diabetes has not been ascertained. The purpose of this study was to measure the exercise intensity and self-efficacy of PBTE, and to determine whether PBTE is a useful tool for exercise therapy. MATERIALS AND METHODS: The participants were 20 patients with type 2 diabetes, and the duration of exercise using the PBTE was set to 10 min. Oxygen consumption during exercise was measured, and self-efficacy for continuing to exercise using the PBTE and for walking was evaluated after completion of the study. RESULTS: The average exercise intensity using the PBTE was 1.7 metabolic equivalents, whereas the maximum exercise intensity was an average of 2.0 metabolic equivalents; the reported self-efficacy for continuing to exercise using the PBTE was significantly higher than for walking. CONCLUSIONS: Exercise intensity using the PBTE is similar to low-intensity walking, and thus, it might be a useful therapeutic exercise device for patients with type 2 diabetes. Furthermore, it could be an effective exercise device for diabetes patients who do not have regular exercise habits, especially with reduced motor function or lower leg muscle strength.

L-cysteine improves blood fluidity impaired by acetaldehyde: In vitro evaluation.

Blood fluidity is reportedly influenced by the volume and function of blood cells and plasma and is a predictor of primary cardiovascular events in patients with traditional cardiovascular risk factors. Heavy alcohol consumption was shown to be associated with a higher risk for cardiovascular diseases. Acetaldehyde (ACD), an oxidizing substance formed from ethanol, reportedly stimulates monocyte adhesion, causes abnormalities in the red blood cell (RBC) membrane, and decreases RBC deformability. In addition, it was reported that blood ACD levels are reduced in mice pretreated with L-cysteine. However, there are no studies on the effect of ACD and/or L-cysteine on blood fluidity. In the present study, we evaluated whether ACD impairs blood fluidity. In addition, the effect of L-cysteine on blood fluidity impaired by ACD was examined. Blood samples were obtained from 10 healthy, non-smoking, male volunteers (age: 23.4 ± 1.2 years, body mass index: 21.8 ± 2.6 kg/m2). ACD or ACD and L-cysteine were added to the blood samples before each experiment. We measured the passage time of 100 µL blood and RBC suspension using Kikuchi's microchannel method. Percentage of microchannel obstruction and the number of adherent white blood cells (WBCs) on microchannel terrace were counted. The blood passage time, percentage of microchannel obstruction, and numbers of adherent WBCs on the microchannel terrace increased after adding ACD in a concentration-dependent manner, whereas they decreased after adding ACD and L-cysteine in a L-cysteine concentration-dependent manner. No significant effects were observed in passage time for 100 µL RBC suspension after adding ACD and L-cysteine. This study suggested that blood fluidity impaired by ACD might improve after adding L-cysteine.

Effects of Hochuekkito combined with pulmonary rehabilitation in patients with chronic obstructive pulmonary disease.

Chronic obstructive pulmonary disease (COPD) has significant systemic effects, such as weight loss, which affects exercise capacity, health-related quality of life (HRQOL) and survival. The traditional herbal medicine, Hochuekkito (TJ-41), improves the nutritional status and decreases systemic inflammation in patients with COPD. However, to date, the additive effect of TJ-41 on pulmonary rehabilitation (PR) in patients with COPD has not been researched comprehensively. The purpose of the present study was to investigate the efficacy and safety of adding TJ-41 to PR for patients with COPD. Thirty-three malnourished patients with COPD were randomly assigned to receive low-intensity exercise with (TJ-41 group) or without (control group) TJ-41 treatment for 12 weeks. The primary outcome was the change in the 6-min walk distance (6MWD). Secondary outcomes included changes in the body composition, peripheral muscle strength, modified Medical Research Council dyspnea score, visual analog scale (VAS) score for dyspnea, VAS score for fatigue and COPD assessment test (CAT) score. After the 12-week treatment, body weight and percent ideal body weight were significantly increased in the TJ-41 group (P<0.05), but not in the control group. After the 12-week treatment, the modified Medical Research Council dyspnea score, VAS score for dyspnea, VAS score for fatigue and total CAT score decreased significantly in the TJ-41 group (all P<0.05), but not in the control group. There were no significant differences in the 6MWD and peripheral muscle strength between baseline and after 12 weeks of treatment in either group. No adverse effects were noted with the use of TJ-41. It was concluded that the addition of TJ-41 to PR may benefit malnourished patients with COPD with respect to dyspnea and HRQOL.

Posture and firmness changes in a pressure-relieving air mattress affect cough strength in elderly people with dysphagia.

Dysphagia is the major pathophysiologic mechanism leading to aspiration pneumonia in the elderly. Elderly people with dysphagia who show low levels of the cough peak flow (CPF) are at greater risk for aspiration pneumonia. It has been reported that CPF values were significantly lower in the "soft" versus "hard" mode of a pressure-relieving air mattress in healthy volunteers in a supine position. Parameters such as spinal curvature, however, were not evaluated in detail. In this study, we clarified whether the changes in posture associated with two different firmness levels of a pressure-relieving air mattress were associated with cough production and related factors in the elderly with dysphagia. The body sinking distance, pelvic tilt angle, and immersion of the lumbar spine were measured to evaluate changes in posture. Forty subjects met the study criteria for dysphagia. The "soft" mode showed significantly lower CPF values than the "hard" mode (soft 274.9 ± 107.2 L/min vs. hard 325.0 ± 99.5 L/min, MD 50.0 95%CI 33.1-66.9 P < 0.001). Values of forced vital capacity (FVC) and maximal inspiratory pressure (PImax) were significantly lower in the "soft" mode than in the "hard" mode (MD 0.10 95%CI 0.04-0.17, P = 0.002, MD 3.2 95%CI 0.9-5.5, P = 0.007, respectively). Although there was no significant difference between the two firmness levels, maximal expiratory pressure (PEmax) values also tended to be lower in the "soft" than in the "hard" mode, (MD 2.9 95%CI -0.6-6.3 P = 0.1). At both firmness levels, CPF values were significantly correlated with FVC, PImax, and PEmax. The difference in sinking distance in the anterior superior iliac spine was significantly larger than that in the lesser tubercle of the humerus and patella. Additionally, in the soft mode, the pelvic tilt angle and contact area around the lumbar spine were significantly larger than those observed in the "hard" mode. Parameters associated with the production of cough, including inspiratory muscle strength, lung volume, and ultimately CPF, may be affected by immersion of the lumbar spine and curvature of the spine that results from the "soft" mode in elderly patients with dysphagia.

A Mobile Cough Strength Evaluation Device Using Cough Sounds.

Although cough peak flow (CPF) is an important measurement for evaluating the risk of cough dysfunction, some patients cannot use conventional measurement instruments, such as spirometers, because of the configurational burden of the instruments. Therefore, we previously developed a cough strength estimation method using cough sounds based on a simple acoustic and aerodynamic model. However, the previous model did not consider age or have a user interface for practical application. This study clarifies the cough strength prediction accuracy using an improved model in young and elderly participants. Additionally, a user interface for mobile devices was developed to record cough sounds and estimate cough strength using the proposed method. We then performed experiments on 33 young participants (21.3 ± 0.4 years) and 25 elderly participants (80.4 ± 6.1 years) to test the effect of age on the CPF estimation accuracy. The percentage error between the measured and estimated CPFs was approximately 6.19%. In addition, among the elderly participants, the current model improved the estimation accuracy of the previous model by a percentage error of approximately 6.5% (p < 0.001). Furthermore, Bland-Altman analysis demonstrated no systematic error between the measured and estimated CPFs. These results suggest that the developed device can be applied for daily CPF measurements in clinical practice.

Estimation of Cough Peak Flow Using Cough Sounds.

Cough peak flow (CPF) is a measurement for evaluating the risk of cough dysfunction and can be measured using various devices, such as spirometers. However, complex device setup and the face mask required to be firmly attached to the mouth impose burdens on both patients and their caregivers. Therefore, this study develops a novel cough strength evaluation method using cough sounds. This paper presents an exponential model to estimate CPF from the cough peak sound pressure level (CPSL). We investigated the relationship between cough sounds and cough flows and the effects of a measurement condition of cough sound, microphone type and participant's height and gender on CPF estimation accuracy. The results confirmed that the proposed model estimated CPF with a high accuracy. The absolute error between CPFs and estimated CPFs were significantly lower when the microphone distance from the participant's mouth was within 30 cm than when the distance exceeded 30 cm. Analysis of the model parameters showed that the estimation accuracy was not affected by participant's height or gender. These results indicate that the proposed model has the potential to improve the feasibility of measuring and assessing CPF.

Effect of body weight support on predicted locomotive physical activity.

[Purpose] This study aimed to evaluate the effect of body weight support with an assistive device on predicted locomotive physical activity measured using triaxial accelerometers in healthy young subjects. [Subjects and Methods] Sixteen healthy subjects aged 21.9 ± 1.1 years walked on a treadmill at speeds of 45 and 55 meters/min under 0%, 10%, 20%, and 30% body weight support conditions. Predicted metabolic equivalents and number of steps were evaluated using triaxial accelerometers. Measured metabolic equivalents and number of steps were evaluated using a metabolic system and observers, respectively. Raw data of synthetic accelerations were also obtained. [Results] Predicted metabolic equivalents and number of steps and raw data of synthetic accelerations decreased with increasing amounts of body weight support. [Conclusion] These findings suggest that accelerometers may underestimate locomotive physical activity with increasing amounts of body weight support using assistive devices. Thus, it is important to consider the amount of body weight support when assessing physical activities in subjects using assistive devices for mobility.

Association between aerobic capacity and the improvement in glycemic control after the exercise training in type 2 diabetes.

BACKGROUND: We investigated the influence of aerobic capacity on the improvement in glycemic control achieved by long-term aerobic exercise in type 2 diabetes. METHODS: Fifty-three male patients with type 2 diabetes, recruited from outpatient clinics, wore multiple-memory accelerometers and were instructed to exercise at moderate intensity for ≥30 min on ≥3 days per week over 12 months. Peak oxygen uptake (peak [Formula: see text]) and serum glycated albumin (GA) were measured at baseline and after 3, 6, 12 months. Peak [Formula: see text] data were expressed as percentages of predicted values. RESULTS: According to the number of bouts of exercise (intensity, ≥4 METs; duration, ≥15 min), the subjects were divided into inactive (<3 times per week) or active (≥3 times per week) groups. Serum GA decreased significantly after 3, 6, 12 months only in the active group. When the subjects were assigned to four groups according to initial peak [Formula: see text] (%pred) (low-fitness or high-fitness) and the number of bouts of exercise (active or inactive), serum GA decreased significantly after 3, 6, 12 months only in the high-fitness/active group. When the subjects were also assigned to four groups according to the change in peak [Formula: see text] (%pred) (improved or unimproved) and the number of bouts of exercise (active or inactive), serum GA decreased significantly after 3 and 12 months only in the improved/active group. CONCLUSION: The improvement in glycemic control achieved by aerobic exercise was associated with both the initial and the increase in peak [Formula: see text] during aerobic exercise.

Effect of Different Levels of Pressure Relieving Air-Mattress Firmness on Cough Strength.

Cough is an important host-defense mechanism. The elderly and patients who are severely ill cannot cough effectively when lying in the supine position. Furthermore, pressure relieving air-mattresses are recommended for preventing the development of pressure ulcers. In this study, we clarified whether or not the cough peak flow (CPF), an index of cough strength, is affected by different firmness levels of a pressure relieving air-mattress in healthy volunteers in the supine position. Fifty-two healthy young men participated. All the measurements were carried out on each participant in the supine position on a pressure relieving air-mattress. The participants were assessed at two firmness levels, a "hard" and "soft" mode. The CPF, forced vital capacity (FVC), maximal expiratory pressure (PEmax), and maximal inspiratory pressure (PImax) were determined for each mode. The sinking distance of the body into the mattress was measured without any activity and the difference between the sinking distances of the two firmness levels was determined. The CPF, FVC, PEmax, and PImax were determined for each mode. The sinking distance of the body into the mattress was measured and the difference between the sinking distances of the two firmness levels was determined. The CPF, FVC, PEmax and PImax values of the participants coughing on the mattress were significantly lower when the mattress was in "soft" than in "hard" mode. The differences between the sinking distances of the mattress in "soft" and "hard" modes were larger for the anterior superior iliac spine. A harder mattress may lead to increased CPF in healthy young men lying in the supine position, and increased CPF may be important for host defense.

Cardiac parasympathetic outflow during dynamic exercise in humans estimated from power spectral analysis of P-P interval variability.

NEW FINDINGS: What is the central question of this study? Should we use the high-frequency (HF) component of P-P interval as an index of cardiac parasympathetic nerve activity during moderate exercise? What is the main finding and its importance? The HF component of P-P interval variability remained even at a heart rate of 120-140 beats min(-1) and was further reduced by atropine, indicating incomplete cardiac vagal withdrawal during moderate exercise. The HF component of R-R interval is invalid as an estimate of cardiac parasympathetic outflow during moderate exercise; instead, the HF component of P-P interval variability should be used. The high-frequency (HF) component of R-R interval variability has been widely used as an indirect estimate of cardiac parasympathetic (vagal) outflow to the sino-atrial node of the heart. However, we have recently found that the variability of the R-R interval becomes much smaller during dynamic exercise than that of the P-P interval above a heart rate (HR) of ∼100 beats min(-1). We hypothesized that cardiac parasympathetic outflow during dynamic exercise with a higher intensity may be better estimated using the HF component of P-P interval variability. To test this hypothesis, the HF components of both P-P and R-R interval variability were analysed using a Wavelet transform during dynamic exercise. Twelve subjects performed ergometer exercise to increase HR from the baseline of 69 ± 3 beats min(-1) to three different levels of 100, 120 and 140 beats min(-1). We also examined the effect of atropine sulfate on the HF components in eight of the 12 subjects during exercise at an HR of 140 beats min(-1) . The HF component of P-P interval variability was significantly greater than that of R-R interval variability during exercise, especially at the HRs of 120 and 140 beats min(-1). The HF component of P-P interval variability was more reduced by atropine than that of R-R interval variability. We conclude that cardiac parasympathetic outflow to the sino-atrial node can be estimated better by the HF component of P-P interval variability during exercise and that cardiac parasympathetic nerve activity exists during moderate dynamic exercise.

The effect of exercise on blood fluidity: Use of the capillary model to assess the clogginess of blood.

AIM: The goal was to evaluate the effects of exercise on the clogginess of blood as well as the effect of increased blood cell count and hematocrit levels after exercise. We also investigated the mechanisms underlying the clogginess of blood. METHODS: The time required for blood to pass through microchannels was measured. We focused on assessing the consecutive passage times for serial 20 µL volumes. We used heparinized peripheral blood obtained from subjects after exercise conducted at three intensity levels. Blood samples were also adjusted to achieve specific hematocrit levels or supplemented by addition of adenosine diphosphate (ADP). RESULTS: The sequential blood passage times of consecutive 20 µL volumes increased with platelet aggregation and adhesion of white blood cells (WBC). We also observed an increase with blood cell counts and hematocrit levels. These changes occurred after high intensity exercise but not after low or medium intensity exercise. Furthermore, the sequential blood passage times of 20 µL volumes increased with platelet aggregation and adhesion of WBC at an ADP concentration at the threshold of aggregation but not at higher levels of hematocrit. CONCLUSIONS: These findings suggested that high intensity exercise might induce the clogginess of blood by enhanced platelet aggregation and adhesion of WBC.

Phase-dependent modulation of corticospinal excitability during the observation of the initial phase of gait.

This study was undertaken to identify the temporal characteristics of corticospinal excitability of tibialis anterior muscle during the observation of the initial phase of gait. For this purpose, using transcranial magnetic stimulation, we recorded motor evoked potentials (MEPs) during the observation of the second step of an actor's first three steps of gait initiation with (complex gait) or without (normal gait) an obstacle and unstable surface. The results demonstrate that (1) MEPs during the observation of the initial phase of normal gait were significantly increased only at early swing phase, but not other phases (mid-swing, heel contact, mid-stance, and heel off) and (2) MEPs during the observation of the initial phase of complex gait were significantly increased at early swing and also at mid-swing and heel contact phases. These findings provide the first evidence that corticospinal excitability during the observation of gait, especially the initial phase, is modulated in phase- and motor-demanded-dependent manners.

Cigarette Smoking does not Induce Plasma or Pulmonary Oxidative Stress after Moderate-intensity Exercise.

[Purpose] Cigarette smoking increases oxidative stress, which is a risk factor for several diseases. Moreover, strenuous exercise has been shown to induce plasma and pulmonary oxidative stress in young cigarette smokers. However, no previous reports have demonstrated whether plasma and pulmonary oxidative stress occur after moderate-intensity exercise. Therefore, the aim of this study was to clarify whether moderate-intensity exercise induces pulmonary and plasma oxidative stress in smokers. [Subjects] Ten young male smokers and 10 young male nonsmokers participated in this study. [Methods] Plasma hydroperoxide concentrations were measured at baseline and then immediately and 15 min after moderate-intensity exercise. Hydrogen peroxide concentrations in exhaled breath condensate were measured at baseline and after exercise. [Results] No significant interactions were found between smokers and nonsmokers in terms of hydroperoxide or hydrogen peroxide concentrations following moderate-intensity exercise at any time point. [Conclusion] These findings suggested that moderate-intensity exercise did not induce plasma or pulmonary oxidative stress in young cigarette smokers.

Plasma oxidative stress is induced by single-sprint anaerobic exercise in young cigarette smokers.

Cigarette smoking increases oxidative stress, which is a risk factor for several diseases. Smoking has also been reported to enhance plasma oxidative stress during strenuous exercise. However, no prior study has examined the changes in plasma oxidative stress after single-sprint anaerobic exercise in cigarette smokers. The purpose of this study was to investigate these changes in young cigarette smokers by measuring reactive oxygen species generation and total antioxidant content. Participants were 15 male smokers (mean age: 25·9 ± 2·9 years) and 18 male non-smokers (mean age: 24·2 ± 4·3 years). Hydroperoxide concentration and biological antioxidant potential (BAP) in plasma were measured at baseline and after the Wingate anaerobic test. A significant interaction between group and time was observed for plasma hydroperoxide concentration (P = 0·037). Plasma hydroperoxide concentration was significantly increased after exercise in both smokers and non-smokers (P = 0·001 and <0·001, respectively). However, no significant interaction was observed between groups by time on plasma BAP (P = 0·574), and a main effect of time was observed (P<0·001). Plasma BAP was significantly increased after exercise in both groups (both, P<0·001). These findings indicate that plasma oxidative stress is higher in cigarette smokers than in non-smokers after single-sprint anaerobic exercise, which may increase the risk of oxidative damage.

Characteristics of patients with severe heart failure exhibiting exercise oscillatory ventilation.

This study aims to elucidate the characteristics of patients with severe nonischemic heart failure exhibiting exercise oscillatory ventilation (EOV) and the association of these characteristics with the subjective dyspnea. Forty-six patients with nonischemic heart failure who were classified into the New York Heart Association (NYHA) functional class III underwent cardiopulmonary exercise testing (CPX) and were divided into two groups according to the presence or absence of EOV. We evaluated the patients by using the Specific Activity Scale (SAS), biochemical examination, echocardiographic evaluation, results of CPX and symptoms during CPX (Borg scale), and reasons for exercise termination. EOV was observed in 20 of 46 patients. The following characteristics were observed in patients with EOV as compared with those without EOV with statistically significant differences: more patients complaining dyspnea as the reason for exercise termination, lower SAS score, higher N-terminal pro-brain natriuretic peptide level, larger left atrial dimension and volume, left ventricular end-diastolic volume, higher Borg scale score at rest and at the anerobic threshold, higher respiratory rate at rest and at peak exercise, and higher slope of the minute ventilation-to-CO2 output ratio, and lower end-tidal CO2 pressure at peak exercise. Among the subjects with NYHA III nonischemic heart failure, more patients with EOV had a stronger feeling of dyspnea during exercise as compared with those without EOV, and the subjective dyspnea was an exercise-limiting factor in many cases.