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Volume 49 (1994 - 199･･･
- Issue 6 Pages 950-
- Issue 5 Pages 852-
- Issue 4 Pages 753-
- Issue 3 Pages 637-
- Issue 2 Pages 533-
Volume 49, Issue 3
Displaying 1-7 of 7 articles from this issue
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Toru TAKEUCHI, Kanehisa MORIMOTO1994 Volume 49 Issue 3 Pages 637-644
Published: August 15, 1994
Released on J-STAGE: February 17, 2009
JOURNAL FREE ACCESSA great number of genotoxins are known to be present in the environment. These genotoxins induce many kinds of DNA damage, and may cause changes in genetic information and cancer. Therefore, evaluation of such DNA damage is important to keep genetic information stable and to prevent cancer. We reviewed here methods used to assay the damage and the importance of this DNA damage in mutation. DNA damage is categorized into two groups, strand breaks and base modifications. To assay DNA strand breaks, the alkaline elution method, pulsed-field gel electrophoresis and single-cell gel assay are being used. The alkaline elution method determines both single-and doublestrand breaks sensitively and quantitatively. Pulsed-field gel electrophoresis preferentially determines double-strand breaks, and the results of the method appeal to the eye as an electrophoretogram. The single-cell gel assay could determine both single-and double-strand breaks even in a single cell, and could evaluate susceptibility to the damage in individual cells. To assay base modifications, methods to detect differences in the physicochemical properties of the damage (physicochemical methods), immunoassays and the 32P-postlabeling method are being used. Physicochemical methods are suitable for chemically minor and abundant modifications such as those in 8-hydroxyguanine, using high-performance liquid chromatography or gas chromatography/mass spectroscopy. Immunoassays, by the use of specific antibodies against DNA damage, are highy sensitive to DNA damage such as changes in O6-methylguanine and thymine glycol, and simple once the assay systems have been established. The 32P-postlabeling method is the most sensitive for the detection of bulky DNA adducts. Indirect methods are also being used to estimate base modifications. Determination of protein-genotoxin adducts may become an alternative to detect DNA adducts wi hout handling DNA. To assay modified bases excreted in urine may also be used to estimate DNA modifications present in tissues. However, every method has shortcomings and no method is perfect. Thus, to effectively evaluate DNA damage a combination of the above methods or the most suitable method for the genotoxin of interest should be used.View full abstractDownload PDF (1124K) -
Yoshio ONO, Shigeyuki NAKAJI, Kazuo SUGAWARA, Takashi KUMAE1994 Volume 49 Issue 3 Pages 645-653
Published: August 15, 1994
Released on J-STAGE: February 17, 2009
JOURNAL FREE ACCESSMany metal materials are used in clinical medicine and the number used is increasing. However, there are a few papers concerning the biological effects, especially effects of clinically used metals on cellular immunity.
In this paper, silver (Ag), nickel (Ni), cobalt (Co), and chromium (Cr), clinically commonly used metals, the effects of which on neutrophilic activity have already reported using the luminol-dependent chemiluminescence (LDCL) method, were examined to determine their influence on the reactive oxygen species (ROS) generating capacity of human neutrophils and on a serum opsonic activity.
Silver suppressed the ROS generating capacity of neutrophils in a dose-dependent manner but did not affect the serum opsonic activity. Nickel also suppressed the ROS generating capacity of neutrophils but, at some concentrations, caused the serum opsonic activity to increase. In contrast, Cobalt increased both the ROS generating capacity of neutrophils and the serum opsonic activity. Like silver, chromium did not affect the serum opsonic activity and suppressed the ROS generating capacity of neutrophils. However, the suppression of ROS generating by chromium occurred differently from that of silver. In the cases of nickel and cobalt, effects of these metals on hemolyzing activity of serum complements (CH-50) were measured and consumption of complements was observed at the same metal concentration at which serum opsonic activity was elevated.
In this paper, we report that some metals influence not only the ROS generating capacity of neutrophils but also the serum opsonic activity, results thought to be important for more details studies of the effects of metals on cellular immunity.View full abstractDownload PDF (1163K) -
Hideya IWASAKI, Ryoichi INABA, Hirotoshi IWATA1994 Volume 49 Issue 3 Pages 654-659
Published: August 15, 1994
Released on J-STAGE: February 17, 2009
JOURNAL FREE ACCESSThe maxium biting force in 82 male athletes and 12 male subjects without any particular athletic activity (nonathletes) were measured in order to evaluate the relationship between biting force and physical fitness in athletes.
The results obtained were as follows.
1. The maximum biting force in athletes (50.8±17.4kg) was significantly (p<0.01) higher than that in the nonathletes (28.1±9.1kg). The maximum biting forces in the men who belonged to the rugby or judo clubs were predominantly higher than in other subjects.
2. In men who masticated on the left side of the mouth, the habitual (i. e., left) biting force was significantly higher than the nonhabitual (i. e., right) biting force.
In men who masticated on the right side of the mouth, the habitual (i. e., right) biting force was also higher than the nonhabitual (i. e., left) biting force, but was not significantly so.
3. There was a significant positive correlation between the biting force and grip strength and back strength in athletes. In athletes, there was a significant correlation between biting force and the numbers of chin-ups, the numbers for the side-step tests and the time for 50m running.View full abstractDownload PDF (776K) -
Masanori FUKUDA1994 Volume 49 Issue 3 Pages 660-664
Published: August 15, 1994
Released on J-STAGE: February 17, 2009
JOURNAL FREE ACCESSThe effects of methylmercuric chloride (MMC) on the growth and cell membrane of the ciliate protozan Tetrahymena pyriformis GL were studied.
The compostions of fatty acids in the cell membrane lipids, which were extracted from cells cultured in medium containing MMC at 30 and 20°C, were examined. As compared with control cells, 30°C-cells were richer in saturated fatty acids than 20°C-cell, indicating that the cell membrane of 30°C-cells was rigid and that that of 20°C-cells was mobile. When MMC was added to the culture media, the amount of unsaturated fatty acid in the cell membrane tended to decrease, resulting in an increase of rigidity of the cell membrane.
When ergosterol was added to the media, the cell membrane became more rigid, and lipids were richer in saturated fatty acids. Ergosterol contributed to reduce the composition change due to addition of MMC to the media.View full abstractDownload PDF (685K) -
Akane KATAGIRI, Hidetoshi KASHIHARA, Yuichiro HARUNA, Yoji SUZUKI, Kaz ...1994 Volume 49 Issue 3 Pages 665-673
Published: August 15, 1994
Released on J-STAGE: February 17, 2009
JOURNAL FREE ACCESSThe purpose of this study is to evaluate the baroreflex function using lower body negative pressure (LBNP) and neck suction in young normotensive men with or without a family history of hypertension. Twenty-two young normotensive men with a family history of hypertension (FH+) and eight young normotensive men who had no family history of hypertension (FH-) were studied. FH(+) consisted of men who had a family history of hypertension within second degree relatives.
We studied cardiopulmonary baroreflex function using LBNP and carotid sinus baroreflex function using neck suction and evaluated the reflex function under stimulated conditions using both LBNP and neck suction at the same time.
Systolic arterial pressure (SAP) (F=5.42, p<0.0001) and pulse pressure (PP) (F=15.57, p<0.0001) decreased similarly in both groups in response to LBNP. SAP and PP responses to LBNP were not significantly affected by the family history of hypertension. Diastolic arterial pressure (DAP) increased (F=2.89, p<0.005) in both groups. There was a relationship between the LBNP level and family history of hypertension (F=2.53, p<0.013), and the increment in DAP during LBNP -30, -40mmHg was larger in the FH(+) group. Though mean arterial pressure (MAP) was not effected by LBNP, there LBNP level was related to the family history of hypertension (F=2.23, p<0.02). Heart rate increased progressively (F=25.7, p<0.0001) with increasing levels of LBNP; however, these changes did not differ significantly in either group. The hemodynamic responses to neck suction and both LBNP and neck suction were not affected by the family history of hypertension. Forearm vascular resistance increased considerably just after starting LBNP and the increment was slightly greater in FH(+) than FH(-) (p=0.08). Plasma epinephrine and norepinephrine concentrations increased in response to LBNP, LBNP and neck suction, decreased in response to neck suction in both groups.
These results suggest that cardiopulmonary baroreflex restraint on sympathetic vasomotor outflow is augmented in normotensive young men with a family history of hypertension, while carotid sinus baroreflex function is not different between the two groups.View full abstractDownload PDF (1193K) -
(Part 1) Relationship of Age and Menopause to Bone Mineral Density of the Lumbar Spine Measured by Dual-energy X-ray AbsorptiometryEtsuko KAJITA, Masayuki IKI, Harumi NISHINO, Yoshiko DOHI, Tadashige M ...1994 Volume 49 Issue 3 Pages 674-683
Published: August 15, 1994
Released on J-STAGE: March 31, 2009
JOURNAL FREE ACCESSBone mineral density (BMD) of the lumbar spine in 198 community-dwelling Japanese women aged 35 years and over was measured by dual-energy X-ray absorptiometry to investigate the effects of aging and menopause on BMD.
A highly significant negative correlation between age and BMD was observed in postmenopausal women as widely accepted. We found a weak but statistically significant negative correlation between age and BMD in even premenopausal women, suggesting that their bone loss had commenced before menopause. Marked decrement in BMD was seen during the first ten years after menopause. Menopause clearly accelerated bone loss in the lumbar spine. Two-way analysis of variance of BMD on age and menopausal status showed that these explanatory variables had a significantly decreasing effect on BMD independently of each other. Menopausal status had a greater sum of squares than age, which suggested that menopause played a greater role in bone loss than did aging. Early menopause has been implied as one of the risk factors for bone loss. The women aged 50 to 59 having encountered menopause before 49 years old exhibited significantly lower BMD than those of similar age who experienced menopause at age 49 and older. This difference in BMD was not observed in the women aged 60 and over. Early menopause was no more likely to be a risk factor for bone loss in the elderly wonen.
We conclude that bone loss in the lumbar spine begins before menopause and is accelerated markedly by menopause for about ten years, and that menopause has a greater decreasing effect on the bone mass than does chronological age while each of them has an independent effect on the bone mass decrement.View full abstractDownload PDF (3983K) -
1994 Volume 49 Issue 3 Pages 736
Published: 1994
Released on J-STAGE: February 17, 2009
JOURNAL FREE ACCESSDownload PDF (32K)
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