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Biomedical subjects

K Nogawa

Publications and source records attributed to K Nogawa.

At least 55 records · Page 3Linked to original sources

Dose-response relationship between urinary cadmium and metallothionein in a Japanese population environmentally exposed to cadmium.

The dose-response relationship between cadmium (Cd) exposure and renal dysfunction, as measured by urinary Cd and metallothoinein (MT), was evaluated in a population living in the Kakehashi River basin, a Cd-polluted area in Japan. Morning urine specimens were collected from 1397 men and 1713 women who were 50 years or older. In addition, urine specimens were collected from a control population consisting of 110 men and 130 women. The 97.5% upper limits for MT in the control population were used to determine the prevalence rates for MT-uria at various urinary Cd concentrations. Probit linear regression analysis showed significant dose-response relationships between MT and Cd. In the control population, prevalence rates of MT-uria for men and women were 1.8 and 3.1%, respectively. Based on the prevalence rates of MT-uria in the control population, the upper limits for the urinary Cd concentrations were calculated from the slopes of the regression lines to be 4.2 and 4.8 micrograms/g creatinine for men and women, respectively. These values, which are similar to those reported previously using urinary beta 2-microglobulin as the indicator, may be of use in establishing the biological threshold, i.e. maximum allowable concentration, for urinary Cd in the environmentally exposed Japanese population.

Age Factors↗

Significant increase of urinary mucoprotein in environmental-cadmium-exposed Japanese subjects.

Urinary mucoprotein (U-MP) was determined in 169 Japanese environmental-cadmium-exposed and 81 non-exposed subjects. Urinary total protein, albumin, beta 2-microglobulin (beta 2-MG), cadmium (Cd) and creatinine were also measured. Significant increases in U-MP and other proteins were found in the Cd-exposed subjects. Significant correlations between each protein were seen in the Cd-exposed and the total group of subjects. U-MP was highly correlated with urinary beta 2-MG and their correlation coefficient was the highest in the total group of subjects. beta 2-MG was the most sensitive indicator among them to detect Cd-induced renal dysfunction, although beta 2-MG is degraded in urine with a pH less than 5.5 U-MP is an acid-soluble protein. Therefore, U-MP is also available for studies on renal dysfunction caused by exposure to Cd, in conjunction with beta 2-MG.

Albuminuria↗

Serum vitamin D metabolites in cadmium-exposed persons with renal damage.

Serum concentrations of 25-hydroxyvitamin D [25(OH)D], 24,25-dihydroxyvitamin D [24,25(OH)2D], and 1 alpha,25-dihydroxyvitamin D [1 alpha,25(OH)2D] were measured in ten cadmium (Cd)-exposed subjects and five non exposed subjects. The Cd-exposed subjects were divided into two groups according to serum 1 alpha,25(OH)2D levels. No significant differences for 25(OH)D were found between the Cd-exposed group with low or normal serum 1 alpha,25(OH)2D and the non exposed group. The concentrations of 24,25(OH)2D were the lowest in the Cd-exposed group with low serum 1 alpha,25(OH)2D, highest in the non exposed group, and significantly lower in the Cd-exposed group with normal serum 1 alpha,25(OH)2D than in the non exposed group. Renal function was much worse in the Cd-exposed group with low serum 1 alpha,25(OH)2D than in the group with normal serum 1 alpha,25(OH)2D. These findings indicate that Cd initially disturbs hydroxylation from 25(OH)D to 24,25(OH)2D and then disturbs hydroxylation from 25(OH)D to 1 alpha,25(OH)2D. The decrease of serum 24,25(OH)2D and 1 alpha,25(OH)2D in Cd-exposed subjects is not due to a decrease of the serum 25(OH)D level.

24,25-Dihydroxyvitamin D 3↗

Prevalence of metallothioneinuria among the population living in the Kakehashi River basin in Japan--an epidemiological study.

An epidemiological study to evaluate cadmium-induced renal dysfunction by urinary metallothionein levels was carried out in an environmentally-exposed Japanese population. The study population consisted of 3168 men and women from a cadmium-polluted area who were 50 years and older and 291 individuals from a non-polluted area. The mean metallothionein levels in urine of the control population were 138.2 +/- 2.1 and 198.6 +/- 1.9 microgram/g creatinine for men and women, respectively. The corresponding values for the cadmium-exposed population were 157.8 +/- 2.2 and 248.0 +/- 2.2. The 97.5% upper limits for men in the control population was determined to be 638 and for women 693 microgram MT/g creatinine. Based on these values as the cut-off levels, the prevalence of metallothioneinuria was calculated to be 4.6% in men and 8.4% in women from the cadmium-polluted area. Further selection of the population, based on life-time residence in the polluted area accompanied with the consumption of cadmium-containing rice, showed an even greater prevalence of metallothioneinuria: 5.4% in men and 10.9% in women of all ages. The prevalence of metallothioneinuria increased with age and duration of residence in the polluted area. These results suggest that metallothioneinuria can be used as an indicator of renal dysfunction due to environmental cadmium exposure.

Age Factors↗

The association between renal dysfunction and osteopenia in environmental cadmium-exposed subjects.

Two hundred and three cadmium (Cd)-exposed subjects with renal dysfunction and 80 non-exposed subjects were examined to reveal the relationship between Cd-induced renal dysfunction and osteopenia. As biological indicators of renal function, urinary beta 2-microglobulin (beta 2-mg), and serum creatinine, calcium, and phosphorus were selected. Cd in the urine and blood was also measured. The results indicated that significant differences exist between both sexes in Cd-exposed as well as nonexposed subjects. To evaluate the degree of osteopenia, a microdensitometrical (MD) method was used. The relationships between biological parameters and each index of the MD method were analyzed using multivariate analysis. Age, urinary beta 2-mg, and serum creatinine were significantly associated with indices of osteopenia in Cd-exposed men. In contrast, age showed the most significant association with MD indices in women of both groups. However, urinary beta 2-mg was significantly associated with MD indices only in Cd-exposed women. In Cd-exposed subjects, after the number of predictor variables was increased, urinary beta 2-mg was also strongly associated with osteopenia. These results suggest a causal relationship between renal dysfunction and osteopenia in Cd-exposed subjects.

Age Factors↗

Dose-response relationship between urinary cadmium and beta 2-microglobulin in a Japanese environmentally cadmium exposed population.

This study was carried out to test the dose-response relationship between urinary cadmium (Cd) and beta 2-microglobulin(beta 2-mg) and also to estimate the biological threshold value of urinary Cd concentration in inhabitants exposed to environmental Cd. Urinary Cd and beta 2-mg were measured in 3178 inhabitants over 50 years of age in the Cd-polluted Kakehashi River basin in Japan and 294 inhabitants in non-polluted areas. Urinary Cd and beta 2-mg were significantly higher in the Cd-exposed subjects than in the non-exposed subjects. Prevalence rates of beta 2-microglobulinuria(beta 2-mg-uria) increased proportionally with increasing urinary Cd concentrations and probit linear regression lines could be calculated between them. The urinary Cd concentration corresponding to the prevalence rates of beta 2-mg-uria among non-exposed subjects was calculated using the regression line, and values of 3.8-4.0 micrograms Cd/g creatinine for men and 3.8-4.1 micrograms Cd/g creatinine for women, respectively, were obtained. These values may be of use in establishing the biological threshold of urinary Cd concentration in environmentally Cd-exposed populations.

Aged↗

Osteopenia in inhabitants with renal dysfunction induced by exposure to environmental cadmium.

Bone density was measured in 28 women with itai-itai disease, 92 men and 114 women with cadmium-induced renal dysfunctions and 44 men and 66 women living in the three different non-polluted areas using a microdensitometer. The values of both indices corresponding to cortical width and bone mineral content were significantly lower in itai-itai disease patients than the cadmium-exposed women with renal dysfunctions and the non-exposed subjects. The cadmium-exposed women also showed a decrease in bone density compared with the non-exposed subjects. A significant decrease in bone density was also observed between cadmium-exposed men and the non-exposed subjects, although the difference was not as clear as in the women. The present study indicates that exposure to cadmium could cause marked osteopenia, particularly in the women.

Aged↗

A dose-response analysis of cadmium in the general environment with special reference to total cadmium intake limit.

An epidemiological study on the dose-response relationship of cadmium was performed on 1850 Cd-exposed and 294 nonexposed inhabitants of the Kakehashi River basin in Ishikawa Prefecture. beta 2-microglobulinuria was used as an index of the effect of cadmium on health and the average cadmium concentration in locally produced rice was employed as an indicator of cadmium exposure. Cadmium exposure was found to affect health in a dose-related manner when the subjects were classified according to the average cadmium concentration in their village rice and their length of residence in the polluted area. Based on the available data, the total cadmium intake that produced an adverse effect on health was calculated as approximately 2000 mg for both men and women.

Aged↗

Relationship between serum gamma-glutamyl transpeptidase activity, blood pressure and alcohol consumption.

The associations among alcohol consumption, gamma-glutamyl transpeptidase (gamma-GTP) activity in serum and blood pressure (BP) were analysed in a cross-sectional study of 1,156 healthy male workers 35 to 59 years of age, consisting of 349 non-drinkers, 682 light-daily drinkers (consuming less than 58 ml of alcohol per day) and 125 heavy-daily drinkers consuming more. No marked elevation of BP with high alcohol consumption was seen in the present subjects. On the other hand, a linear elevation of BP together with an increase in serum gamma-GTP activity was found in subjects above 40 years of age. The BP levels corresponding to the three different drinking habits, non-drinkers, light drinkers and heavy drinkers, were similar to each other regarding gamma-GTP levels. The relationship between gamma-GTP and BP was shown, by multiple regression analysis, to be independent of age, obesity and the dose of alcohol consumed. The contribution to the rise in BP of the dose of alcohol consumed, in comparison with that of gamma-GTP, was negligible. Serum gamma-GTP activity is a useful indicator of the susceptibility to the pressor effect of alcohol.

Adult↗

Leukocytosis and low serum IgA in workers exposed to the epoxy compound, t-methyl-3-phenylglycidate.

Forty-nine out of 54 male workers engaged in the production of an epoxy compound, t-methyl-3-phenylglycidate, showed skin symptoms in varying degrees that may be due to the skin-irritative effect of the compound. The exposed workers were also shown to have subjective symptoms which may be related to the irritative property of the compound on surface tissue. Laboratory examinations on the blood obtained from the exposed workers showed significantly higher values of leukocyte concentration as compared with the non-exposed controls. This was chiefly caused by the increase of neutrophilic granulocytes and T-cell lymphocytes. Serum IgA levels of the exposed workers were shown to be significantly lower than those of the control group. Hemoglobin concentration, hematocrit value and red cell count of the exposed workers remained at the same level as those of the control subjects. Liver or kidney damage was not found in biochemical analyses on the sera of exposed workers.

Adult↗

Selenium, zinc, copper and cadmium concentration in livers and kidneys of people exposed to environmental cadmium.

Selenium (Se), Cadmium (Cd), Zinc (Zn) and Copper (Cu) concentrations have been determined in the kidney cortex, medulla and liver of 21 Cd-exposed and 15 nonexposed autopsied subjects. In the kidney cortex, all four metals were significantly lower in the Cd-exposed subjects than in the nonexposed ones. In the liver Se levels were almost the same in both groups. Significant correlation coefficients between Se and the three metals were found in the kidney cortex of all the subjects. In the liver significant correlation coefficients were only seen between Se and Cu in the Cd-exposed subjects. These results indicated that the distribution of Se in humans chronically exposed to environmental Cd is different from that in humans exposed to environmental organic mercury.

Aged↗

Cadmium, zinc and copper relationships in kidney and liver of humans exposed to environmental cadmium.

Cadmium, copper and zinc have been determined in kidney cortex, kidney medulla and liver from 51 cadmium-polluted and 122 nonpolluted autopsied subjects. Liver cadmium and zinc were significantly higher in the cadmium-polluted subjects than in the nonpolluted subjects. Kidney cadmium, copper and zinc were lower in the cadmium-polluted subjects because of renal damage. Significant correlations of the three metals were found in the kidney. In the liver the correlation coefficients were significant only between cadmium and zinc.

Adolescent↗

Mechanism for bone disease found in inhabitants environmentally exposed to cadmium: decreased serum 1 alpha, 25-dihydroxyvitamin D level.

To investigate the mechanism for bone disease caused by exposure to cadmium serum samples were collected from 5 itai-itai disease patients, 36 Cd-exposed residents with renal tubular damage and 17 non-exposed individuals and analyzed for 1 alpha,25-dihydroxyvitamin D[1 alpha,25(OH)2D], parathyroid hormone, beta 2-microglobulin, calcium and inorganic phosphorus. Measurement of percentage tubular reabsorption of phosphate (%TRP) were performed only on the Cd-exposed subjects. Serum 1 alpha,25(OH)2D levels were lower in itai-itai disease patients and cadmium-exposed subjects with renal damage than in non-exposed subjects. Parathyroid hormone and beta 2-microglobulin concentrations in serum were higher in the Cd-exposed subjects. Decrease in serum 1 alpha,25(OH)2D levels were closely related to serum concentrations of parathyroid hormone, beta 2-microglobulin and %TRP. This study suggests that cadmium-induced bone effects were mainly due to a disturbance in vitamin D and parathyroid hormone metabolism, which was caused by the cadmium-induced kidney damage.

Aged↗

Significance of elevated urinary N-acetyl-beta-D-glucosaminidase activity in chronic cadmium poisoning.

N-Acetyl-beta-D-glucosaminidase (NAG) activity and beta 2-microglobulin (beta 2-m) concentration were measured in the urine of inhabitants of a cadmium-polluted area (Cd), including patients with, or suspected, "itai-itai" disease and control subjects. Urinary NAG activity increased with increasing beta 2-m concentration up to about 100 U/g creatinine; above this value the NAG activity did not increase with increasing beta 2-m concentration. Urinary NAG activity thus represents another useful indicator of renal tubular damage caused by Cd poisoning since the mechanisms for the excretion of NAG and beta 2-m into urine are thought to be different.

Acetylglucosaminidase↗