1.Low Intensity Exercise Dose not Repress the Increase in Portal Venous Flow After a Feeding.
HIROMI YANO ; SACHIFUMI KINOSHITA ; SHOHEI KIRA
Japanese Journal of Physical Fitness and Sports Medicine 2001;50(4):475-482
It is generally accepted that exercise induces a decrease in splanchnic circulation, because of the increase of blood in working skeletal muscle. On the other hand, ingestion of a meal increases blood flow in splanchnic circulation. However, it remains to be clarified whether splanchnic circulation decreases due to exercise after ingestion of a meal. The present study examined the effect of different intensities of cycling exercise after ingestion of a carbohydrate-drink on portal venous blood flow, blood glucose, serum insulin and plasma catecholamine concentrations. Six volunteers ingested 200 ml of martodextrine solution (12%) [M (200) ] before 20 min exercise sessions of 30% maximal oxygen uptake (VO2max) and 60% VO2max. Before and after the exercise sessions, portal venous blood flow was measured by a combined ultrasonic system of an electronic sector scanner and pulsed Doppler flowmeter. Portal venous blood flow in the exercise at 30% VO2max increased due to the M (200) ingestion. However, a decrease in portal blood flow resulting from exercise at 60% VO2max was observed in spite of a M (200) ingestion compared with portal blood flow after both rest and the exercise at 30% VO2max. Immediately after exercise, an increase in blood glucose and serum insulin level was shown for 30% VO2max with M (200), but not 60% VO2max. In addition, plasma epinephrine concentration after taking M (200) did not increase as a result of either exercise intensity.
These results suggest that the response of portal venous blood flow caused by carbohydratedrink ingestion immediately before exercise is influenced by exercise intensity, and it corresponds to the changes in blood glucose, serum insulin and plasma epinephrine. We concluded that ingestion of food, rather than exercise, has a regulatory action in splanchnic circulation in low intensity exercise.
2.A Comparative Study of Dietary Intake among Urban Japanese and Chinese Aged 50$\sim$79
Da-Hong WANG ; Jiong Li ; Shohei KIRA
Environmental Health and Preventive Medicine 2000;5(1):18-24
This study examined the difference in dietary intake between middle−aged and elderly Japanese and Chinese. Volunteers aged 50∼79 living in two cities in both Japan and China were recruited in local community service centers and were asked to complete a 3−day diet recording. The final results were based on 356 subjects (166 Chinese and 190 Japanese). In men, the Japanese subjects significantly consumed more energy, with a large proportion of the energy coming from carbohydrates, dietary fiber, vitamin A, vitamin B2, vitamin C and they consumed less iron, and a lower proportion of energy from protein and fat than in the Chinese subjects. In women, the Japanese subjects had significantly higher intakes of energy, the proportion of energy from carbohydrates, dietary fiber, calcium, vitamin A, vitamin B1, vitamin B2, vitamin C and they consumed less iron, with the proportion of energy from protein and from fat in comparison with the Chinese women. Fat intake provided more than 29% of the total dietary energy in Chinese subjects. Daily intake of food items was significantly greater in the Japanese participants, both men and women (18.54±2.85, 20.11±2.40, respectively), than in the Chinese subjects (14.11±3.62, 15.51±4.15, respectively) (p<0.01 by Mann Whitney U−test). The present study suggests that the middle−aged and elderly Chinese subjects should increase their variety of foods consumed while decreasing their consumption of high−fat foods. For the Japanese subjects, the higher intake of total calories among the woman should also be noted.
Chinese People
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Japanese language
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Energy, Physics
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Human Females
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Elderly
3.Effects of exercise intensity on renal clearance parameters.
HISAO SUZUKI ; KAYO TAKAHASHI ; SOICHIRO YOSHIDA ; SHOHEI KIRA ; KOHJI MIURA ; ZENSUKE OTA
Japanese Journal of Physical Fitness and Sports Medicine 1992;41(2):147-155
A study was designed to examine the effects of exercise intensity on renal clearance parameters. Five healthy male subjects underwent exercise tests on an bicycle ergometer at 4 different work loads for 15 min. The indicators of exercise intensity employed were the percentage of maximal oxygen uptake (%VO2max), heart rate (HR) and blood lactate level (La) . As parameters of renal clearance, para-aminohippurate clearance (CPAH), thiosulfate clearance (Cthio) and creatinine clearance (Ccr) were measured by the continuous infusion technique during the exercise.
1) The renal clearance parameters during exercise decreased linearly as the exercise intensity increased. The percentage of maximal oxygen uptake at the onset of the decreases in %CPAH, %Cchiu and %Ccr were 36, 45 and 47%VO2max, respectively.
2) Among the indicators of exercise intensity, the decrease in La showed the closest correlation with renal clearance during the exercise.
3) The renal plasma flow, which was measured as CPAH, began to decrease linearly at a significantly lower exercise intensity than the glomerular filtration rate, which was measured as both Cthio and Ccr.
The above results suggest that renal clearance parameters begin to decrease at the threshold as exercise intensity increases.
4.Animal model for oxidative stress research-Catalase mutant mice.
Da-Hong WANG ; Noriyoshi MASUOKA ; Shohei KIRA
Environmental Health and Preventive Medicine 2003;8(2):37-40
Catalase-deficient mouse strains was initially established by Feinstein et al. through a large scale screening of the progeny of irradiated C3H mice in 1966. Later, Feinstein provided the mice of catalase mutant strain C3H/AnICs(a)Cs(a) (wild-type), C3H/AnICs(b)Cs(b) and C3H/AnlCs(c)Cs(c) to Okayama University Medical School in Japan. It is known that a point mutation at amino acid 11 (from glutamine to histidine) of acatalasemic mouse catalase and a point mutation at amino acid 439 (from as paragine to serine) of hypocatalasemic mouse catalase are responsible for the catalase deficiency of acatalasemic and hypocatalasemic mice, respectively. Recently, a liver cell line from an acatalasemic mouse andEscherichia coli (E. coli) strains with murine normal, hypocatalasemic, or acatalasemic catalase have been established. The construction of these new systems would be useful for studying the effects of oxidative stress at the cellular level. In this review, we give a brief overview of recent findings of studies in utilizing the catalase-deficient mice and evaluate the possibility of these mouse strains as a candidate animal model for oxidative stress research.
5.Survey of cattle fascioliasis in Tsuyama Abattoir.
Masahiko KATO ; Yasuyuki MURAKAMI ; Motota SHIMIZU ; Hideki YAMAMOTO ; Yumi YONEMOTO ; Ken-Ichi ISHII ; Shohei KIRA
Environmental Health and Preventive Medicine 2005;10(3):162-165
OBJECTIVESThe aim of this study was to survey the prevalence of fascioliasis in slaughtered cattle in order to provide breeders with feedback which may prevent cattle fascioliasis, as well as human fascioliasis.
METHODSThe results of meat inspection and the information extracted from the Discriminative Data Base on Individual Livestock in Japan were analyzed statistically in 6,224 cattle slaughtered at the Tsuyama Abattoir during the fiscal year 2002.
RESULTSThe age-adjusted fascioliasis and cholangitis rates of all cattle were 2.0% and 7.2%, respectively. When analyzed by cattle breed, both rates were significantly higher in Japanese native cattle than in Holstein or Jersey (Chi-square test, p<0.01). The cattle raised in Okayama Prefecture, Tochigi Prefecture and Shimane Prefecture were significantly different from cattle raised in other prefectures in the age-adjusted fascioliasis and cholangitis rates.
CONCLUSIONThe age-adjusted fascioliasis and cholangitis rates of all cattle can be considered as nationwide rates for slaughtered cattle. The results of the comparisons suggest that cattle fascioliasis is related to feeding with rice straw and that the measures to prevent cattle fascioliasis might differ a mong prefectural governments.