1.Effects of acute aerobic repetition exercise on the vascular endothelial function
Yasuaki Tamura ; Hajime Miura ; Kenichi Deguchi ; Ayako Azuma ; Yuji Hashimoto ; Miduki Ishikawa
Japanese Journal of Physical Fitness and Sports Medicine 2017;66(6):437-444
High-intensity interval exercise (IE) leads to greater improvements in the arterial function than continuous exercise at moderate intensity (CE). However, few studies have been performed on the effects of the repetition exercise (RE) on the vascular endothelial function. The purpose of this study was to compare the effects of CE vs. IE vs. RE during aerobic exercise on the vascular endothelial function determined by flow-mediated vasodilation (FMD). Ten healthy male subjects randomly performed 3 trials as follows: CE (20-min cycling at 50%Wmax), IE (10 × 1-min intervals cycling at 75%Wmax interspersed with 1-min intervals cycling at 25%Wmax), and RE (30 × 20-sec intervals cycling at 100%Wmax interspersed with 20-sec intervals at rest). FMD was assessed at rest and 30 and 60 min after each exercise, and then the normalized FMD (nFMD) was calculated from the peak shear rate. The nFMD (a.u.) significant increased 30 min after IE (1.2 ± 0.2 to 3.0 ± 1.0, p<0.05) and increased 30 min after CE (1.0 ± 0.2 to 1.4 ± 0.2, n.s.) and returned to baseline at 60 min after both exercises, while the nFMD decreased 30 min after RE (1.3 ± 0.2 to 1.2 ± 0.1, n.s.) and was sustained at 60 min. The nFMD value at 30 min after IE was significantly greater than that at 30 min after RE (3.0 ± 1.0 versus 1.2 ± 0.1, p<0.05). These results suggest that RE may lead to a less improvement in the vascular endothelial function than CE and IE.
2.Double blind comparative study on the effect of low energy laser irradiation to rheumatoid arthritis.
Kenichi MIYAGI ; Y. OHOTANI ; S. SUZUKI ; A. AMANO ; T. AZUMA ; H. YOSHIZAWA ; A. HASHIMOTO ; Y. ISHIHARA ; K. MATSUTA
The Journal of The Japanese Society of Balneology, Climatology and Physical Medicine 1989;52(3):117-126
In order to investigate the safety and efficacy of low energy laser irradiation to the arthritis of the patients with rheumatoid arthrtis, a multi-center double blind comparative study was conducted.
Sixty eight patients with rheumatoid arthritis were randomly allocated into two groups of laser and sham irradiation. The each inflamed knee joint received 3 minut's irradiation of Ga-AI-As laser at 20mw with wave length of 830nm or 3 minut's sham irradiation, twice a week during 5 weeks. Evaluation items included pain and swelling of the knee joint, 15m walking time, ESR and morning stiffness. Routine laboratory tests including CBC, blood chemistry such as GOT, GPT, and LDH were also examined at the entry of the study and the completion of 10 times irradiation. Among various evaluation items, 15m walking time showed significant decrease in the laser group comparing with that in the sham group (P<0.01). The remaining items showed no significant differences between two groups. Laboratory data showed no remarkable changes during the study and no apparent adverse effect with irradiation was observed.
These results show some beneficial effect of low energy laser therapy to the patient with rheumatoid arthritis and also safety of irradiation.
3.Background factors of chemical intolerance and parent-child relationships.
Kenichi AZUMA ; Masayuki OHYAMA ; Emiko AZUMA ; Takae NAKAJIMA
Environmental Health and Preventive Medicine 2018;23(1):52-52
BACKGROUND:
Chemical intolerance is a widespread public health problem characterized by symptoms that reportedly result from low-level exposure to chemicals. Although several studies have reported factors related to chemical intolerance in adults, the impact of family members has not been reported. In the present study, we investigated the background factors related to chemical intolerance in family members and parent-child relationships.
METHODS:
We distributed a self-reported questionnaire to 4325 mothers who were invited to visit the Kishiwada Health Center in Kishiwada City, Osaka, between January 2006 and December 2007 for the regular health checkup of their three-and-a-half-year-old children.
RESULTS:
The prevalence of chemical intolerance in the 3-year-old children was almost one eighteenth of that reported by their mothers. Multiple logistic regression analyses revealed that cold sensitivity [odds ratio (OR), 1.89; 95% confidence interval (CI), 1.04-3.44], past bronchial asthma (OR, 2.84; 95% CI, 1.46-5.53), and any past allergies (OR, 2.21; 95% CI, 1.36-3.60) were significantly associated with chemical intolerance in the mother. The presence of indoor cat during childhood (OR, 1.99; 95% CI, 1.08-3.69) was significantly associated with chemical intolerance in the mother; however, the association was weak compared with cold sensitivity and past asthma and allergies. The current chemical intolerance of the mother was significantly associated with allergic rhinitis (OR, 2.32; 95% CI, 1.19-4.53), bronchial asthma (OR, 3.66; 95% CI, 2.00-6.69), and chronic bronchitis (OR, 3.69; 95% CI, 1.04-13.03) in her 3-year-old child.
CONCLUSIONS
The results suggest that inherent physical constitution and childhood housing environment are associated with a risk of acquiring chemical intolerance. Children of mothers with chemical intolerance have a possible risk of respiratory hypersensitivity or inflammation. Further investigation is recommended to determine the inherent physical constitution and background environmental factors associated with the risk of acquiring chemical intolerance. The impact of having mothers with chemical intolerance on the health of children also requires further study.
Cross-Sectional Studies
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Fathers
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statistics & numerical data
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Female
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Humans
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Infant
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Infant, Newborn
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Japan
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epidemiology
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Male
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Mothers
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statistics & numerical data
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Multiple Chemical Sensitivity
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epidemiology
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etiology
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Parent-Child Relations
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Prevalence
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Risk Factors
4.Influence of arm-cranking exercise with electrical muscle stimulation on arterial stiffness
Mizuki ISHIKAWA ; Hajime MIURA ; Ayako AZUMA ; Kenichi DEGUCHI ; Yasuaki TAMURA
Japanese Journal of Physical Fitness and Sports Medicine 2019;68(3):183-190
Endurance exercises such as cycling and running are useful for improving the arterial function and preventing cardiovascular disease (CVD). However, subjects suffering from spinal cord injury (SCI) or lower limb osteoarthritis (OA) cannot perform these kinds of lower limb exercises. Recently, electrical muscle stimulation (EMS) has been shown to be able to increase the muscle strength and blood flow and improve the peripheral circulation. Arm-cranking exercises with EMS may therefore be able to reduce the risk of CVD for patients with SCI and lower OA. However, this point has not been fully clarified. The purpose of this study was to assess the effect of submaximal arm-cranking exercise with EMS on arterial stiffness. Ten healthy young subjects performed submaximal arm-cranking exercise alone (A) and submaximal arm-cranking exercise with EMS (A+E). In the A+E trial, the submaximal arm-cranking exercise was performed at 30%VO2 max for 20 min while EMS was applied to their thigh and calf muscles during the exercise. The brachial-ankle pulse wave velocity (ba-PWV), systolic and diastolic blood pressure (SBP/DBP) and heart rate (HR) were measured before and after each exercise. Immediately after the exercise session, the HR of the subjects in the A+E trial was significantly elevated in comparison to those in the A trial. The SBP and DBP did not differ between the two trials to a statistically significant extent. In the A+E trial, the ba-PWV was significantly reduced immediately after exercise in comparison to the A trial (1082.6 ± 105.9 cm·sec-1 vs. 1191.7 ± 86.7 cm·sec-1, p < 0.05). These findings suggest that arm-cranking exercise with EMS reduces arterial stiffness and might be useful for reducing the risk of CVD.
5.Influence of repetition exercise requiring less work than continuous exercise on the vascular endothelial function
Yasuaki TAMURA ; Hajime MIURA ; Kenichi DEGUCHI ; Yuji HASHIMOTO ; Ayako AZUMA ; Mizuki ISHIKAWA
Japanese Journal of Physical Fitness and Sports Medicine 2019;68(3):199-206
High-intensity interval exercise leads to greater improvements in the vascular endothelial function than continuous exercise at moderate intensity. However, few studies have been performed on the effects of repetition exercise consisting of high-intensity exercise followed by complete rest on the arterial function. Therefore, the purpose of this study was to investigate the effects of repetition exercise on the vascular endothelial function determined by flow-mediated vasodilation (FMD). Eleven healthy male subjects completed two exercise sessions on a cycle ergometer in a counterbalanced order. The exercise sessions were 20 min cycling at 50% maximal work rate (Wmax) (continuous exercise, CE) and 20 × 20-sec intervals at 100%Wmax interspersed with 40-sec intervals at complete rest (repetition exercise, RE). Before and after each protocol, the brachial systolic and diastolic blood pressure were measured in the supine position. Relative FMD was assessed at rest and 30 and 60 min after each exercise regimen, and then the normalized FMD (nFMD) was calculated from the peak shear rate. The FMD significantly increased 30 min after RE (8.2 ± 1.5% to 11.5 ± 3.1%, p<0.01) and non-significantly increased 30 min after CE (7.5 ± 1.6% to 8.1 ± 2.1%, n.s.) before returning to baseline at 60 min after both exercise regimens. The FMD value at 30 min after RE was significantly greater than that at 30 min after CE (p<0.01). The nFMD (a.u.) significantly increased 30 min after RE (1.38 ± 0.64 to 2.00 ± 0.94, p<0.05) and non-significantly increased 30 min after CE (1.20 ± 0.54 to 1.49 ± 0.57, n.s.) before returning to baseline at 60 min after both exercise regimens. These results suggest that repetition exercise may lead to an acute improvement in the vascular endothelial function.
6.Chemical intolerance: involvement of brain function and networks after exposure to extrinsic stimuli perceived as hazardous.
Kenichi AZUMA ; Iwao UCHIYAMA ; Mari TANIGAWA ; Ikuko BAMBA ; Michiyo AZUMA ; Hirohisa TAKANO ; Toshikazu YOSHIKAWA ; Kou SAKABE
Environmental Health and Preventive Medicine 2019;24(1):61-61
BACKGROUND:
Chemical intolerance (CI) is a chronic condition characterized by recurring and severe symptoms triggered by exposure to low levels of odorous or pungent substances. The etiology of CI has been a controversial subject for a long time. The aim of this review is to summarize findings on the neurological processing of sensory information during and after exposure to low levels of odorous or pungent substances in individuals with CI, focusing on the brain function and networks.
METHODS:
Scientific studies on CI published between 2000 and 2019 in academic peer-reviewed journals were systematically searched using medical and scientific literature databases. Only peer-reviewed articles reporting original research from experimental human studies directly associated with CI, and involving related neurological responses or brain imaging after exposure to odorous or pungent substances (i.e., in chemical provocation tests), were considered.
RESULTS:
Forty-seven studies were found to be eligible for a full-text review. Twenty-three studies met the selection criteria and were included in this review. Evidence indicated that differences between subjects with CI and healthy controls were observed by brain imaging during and after exposure to odorous or pungent substances. Differences in brain imaging were also observed between initial exposure and after exposure to these substances. Neurological processing of sensory information after exposure to extrinsic stimuli in the limbic system and related cortices were altered in subjects with CI. A previous documentable exposure event was likely to be involved in this alteration.
CONCLUSIONS
This review documents consistent evidence for the altered neurological processing of sensory information in individuals with CI. Further neurophysiological research exploring the processing of extrinsic stimuli and cognition of sensation through the limbic system and related cortices in CI, and the appearance of symptoms in individuals with CI, are required.
7.Environmental factors involved in SARS-CoV-2 transmission: effect and role of indoor environmental quality in the strategy for COVID-19 infection control.
Kenichi AZUMA ; U YANAGI ; Naoki KAGI ; Hoon KIM ; Masayuki OGATA ; Motoya HAYASHI
Environmental Health and Preventive Medicine 2020;25(1):66-66
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a new zoonotic agent that emerged in December 2019, causes coronavirus disease 2019 (COVID-19). This infection can be spread by asymptomatic, presymptomatic, and symptomatic carriers. SARS-CoV-2 spreads primarily via respiratory droplets during close person-to-person contact in a closed space, especially a building. This article summarizes the environmental factors involved in SARS-CoV-2 transmission, including a strategy to prevent SARS-CoV-2 transmission in a building environment. SARS-CoV-2 can persist on surfaces of fomites for at least 3 days depending on the conditions. If SARS-CoV-2 is aerosolized intentionally, it is stable for at least several hours. SARS-CoV-2 is inactivated rapidly on surfaces with sunlight. Close-contact aerosol transmission through smaller aerosolized particles is likely to be combined with respiratory droplets and contact transmission in a confined, crowded, and poorly ventilated indoor environment, as suggested by some cluster cases. Although evidence of the effect of aerosol transmission is limited and uncertainty remains, adequate preventive measures to control indoor environmental quality are required, based on a precautionary approach, because COVID-19 has caused serious global damages to public health, community, and the social economy. The expert panel for COVID-19 in Japan has focused on the "3 Cs," namely, "closed spaces with poor ventilation," "crowded spaces with many people," and "close contact." In addition, the Ministry of Health, Labour and Welfare of Japan has been recommending adequate ventilation in all closed spaces in accordance with the existing standards of the Law for Maintenance of Sanitation in Buildings as one of the initial political actions to prevent the spread of COVID-19. However, specific standards for indoor environmental quality control have not been recommended and many scientific uncertainties remain regarding the infection dynamics and mode of SARS-CoV-2 transmission in closed indoor spaces. Further research and evaluation are required regarding the effect and role of indoor environmental quality control, especially ventilation.
Aerosols
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Air Pollution, Indoor/prevention & control*
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Betacoronavirus/physiology*
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COVID-19
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Coronavirus Infections/transmission*
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Crowding
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Environment, Controlled
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Humans
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Pandemics/prevention & control*
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Pneumonia, Viral/transmission*
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SARS-CoV-2
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Ventilation
8.Lowest observed adverse effect level of pulmonary pathological alterations due to nitrous acid exposure in guinea pigs.
Masayuki OHYAMA ; Hiroshi NISHIMURA ; Kenichi AZUMA ; Chika MINEJIMA ; Norimichi TAKENAKA ; Shuichi ADACHI
Environmental Health and Preventive Medicine 2020;25(1):56-56
BACKGROUND:
We previously demonstrated that continuous exposure to nitrous acid gas (HONO) for 4 weeks, at a concentration of 3.6 parts per million (ppm), induced pulmonary emphysema-like alterations in guinea pigs. In addition, we found that HONO affected asthma symptoms, based on the measurement of respiratory function in rats exposed to 5.8 ppm HONO. This study aimed to investigate the dose-response effects of HONO exposure on the histopathological alterations in the respiratory tract of guinea pigs to determine the lowest observed adverse effect level (LOAEL) of HONO.
METHODS:
We continuously exposed male Hartley guinea pigs (n = 5) to four different concentrations of HONO (0.0, 0.1, 0.4, and 1.7 ppm) for 4 weeks (24 h/day). We performed histopathological analysis by observing lung tissue samples. We examined samples from three guinea pigs in each group under a light microscope and measured the alveolar mean linear intercept (Lm) and the thickness of the bronchial smooth muscle layer. We further examined samples from two guinea pigs in each group under a scanning electron microscope (SEM) and a transmission electron microscope (TEM).
RESULTS:
We observed the following dose-dependent changes: pulmonary emphysema-like alterations in the centriacinar regions of alveolar ducts, significant increase in Lm in the 1.7 ppm HONO-exposure group, tendency for hyperplasia and pseudostratification of bronchial epithelial cells, and extension of the bronchial epithelial cells and smooth muscle cells in the alveolar duct regions.
CONCLUSIONS
These histopathological findings suggest that the LOAEL of HONO is < 0.1 ppm.
Alveolar Epithelial Cells
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drug effects
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Animals
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Bronchi
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drug effects
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Dose-Response Relationship, Drug
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Emphysema
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chemically induced
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Epithelial Cells
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drug effects
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Guinea Pigs
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Hyperplasia
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chemically induced
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Inhalation Exposure
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adverse effects
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Lung
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drug effects
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pathology
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ultrastructure
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Male
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Microscopy, Electron, Scanning
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Microscopy, Electron, Transmission
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Myocytes, Smooth Muscle
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drug effects
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Nitrous Acid
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toxicity