A simplified analysis of polynuclear aromatic hydrocarbons (PAHs) in airborne particulates was investigated by direct extraction from a glass fiber filter using organic solvent, followed by high performance liquid chromatography (HPLC). Airborne particulates were collected on a glass fiber filter (20×25, cm) by a Hi-volume air sampler and a part of the filter (diameter, 16mm) was attached to a cellulose filter by continuous development with ethyl ether for 20min. The separated PAHs spot on the filter was cut off and put into a small test tube and then redissolved in 1ml of acetonitrile.
The PAHs in the extracted acetonitrile solution were analyzed by a reversed phase HPLC equipped with a spectrofluorometer.
Recovery rates of PAHs from airborne particulates with the same fluorescence condition (Ex. 368nm, Em. 406nm) using HPLC were 98.7% for benzo [a] pyrene (BaP), 99.3% for benzo [k] fluoranthene (BkF) and 96.1% for benzo [ghi] perylene (BghiP).
Extraction rates of PAHs in an airborne particulate by using organic solvents were different. The extractible order was as follows, ether > dichloromethane > acetone > tetrahydrofurane > acetonitrile > benzene > ethanol. Ether solvent thus is superior to other solvents for extraction and volatility. Futhermore, it was also proved that distribution of BaP, BkF and BghiP in the cellulose filter was nearly uniform. A test sample was recovered by removing organic substances in the airborne particulates by the ether development. Recovery rates of PAHs ranged from 98.8 to 100.7% for BaP, 97.7-99.5% for BkF and 99.0-103.0% for BghiP. When this method was applied to the determination of BaP, BkF and BghiP in airborne particulates, the analytical data were in good agreement with those by a coventional method; ultrasonic extraction-HPLC method. In this method, extraction carried out on a cellulose filter could recover PAHs sufficiently and does not extracted micro particles, which effects on the separation column, from glass fiber filter collected airborne particulates. Therefore, in this method several kinds of PAHs in airborne particulates including carcinogenic BaP can be analyzed easily and efficiently.

View full abstract

Cd was administered to pregnant and non-pregnant rats in three dosage regimens during the period of onset of pregnancy through nursing to evaluate the behavior of Cd and the distribution of Zn and Cu in the organs: (1) 100μg of Cd was administered subcutaneously once on day 0 of pregnancy (day 0) and the animals were killed on day 20. (2) 5μg of Cd was administered subcutaneously once a day for 5, 8, 11, 14, 17 and 20 days starting with day 0 and the animals were killed 24 hours after the last dose. (3) 5μg of Cd was administered subcutaneously for 20 days from day 0 to day 19 (total 100μg) and the animals were killed on day 20 and at weeks 2, 4, 6 and 8 after delivery.
The following results were obtained.
1) Administration of Cd did not influence the course of pregnancy or the growth of fetuses and neonates.
2) The amount of Cd accumulated in the liver and the kidneys of non-pregnant rats was almost constant on day 20 and after the discontinuation of Cd irrespective of dosing schedule. However, pregnant rats on day 20, when administered Cd repeatedly, tended to show higher levels of accumulated Cd than that of non-pregnant rats. After the discontinuation of Cd, the amount of Cd accumulated in the liver and the kidneys of nursing dams decreased during the lactation period.
3) Though the placenta is presumed to protect the transfer of Cd to the fetus, the transfer of Cd to the fetus was observed as an overflow phenomenon if the placental Cd concentration reached a certain level (0.1μg/g).
4) The transfer of Cd to sucklings through breast milk from dams was found, though minimal. The concentrations of Cd in the liver and the kidneys of weanlings were not affected by the administration of Cd to dams and remarkably increased when the young rats began to take food.
5) In dams, Zn and Cu concentrations were more greatly influenced by pregnancy and nursing than by Cd administration. In non-pregnant rats, Cd administration increased Zn concentration in the liver and Cu concentration in the kidneys.
6) In fetuses and young rats, Zn and Cu concentrations increased only in the kidneys of fetuses on day 20 and moreover only when administered Cd repeatedly.

View full abstract

Hypercholesterolemic children are reported to be increasing in Japan owing to dietary change. To investigate the effects of family histories of cardiovascular diseases and habits of daily food intake on serum lipid levels and also to investigate the difference in physical growth rate according to cholesterol levels, questionaires were given to 157 third year girl students of junior high schools and their parents in the town of Nagakute in the suburbs of Nagoya city. Bloodsamples were collected from all the girl students.
The mean total cholesterol concentration of 159mg/dl and the frequency of hypercholesterolemic children (total cholesterol≥200mg/dl) of 5.7% were similar to previous results from other areas in Japan. There was no apparent relationship between family history and serum cholesterol levels. The hypercholesterolemic students ate vegetables less frequently and confectioneries more frequently than normocholesterolemic students.
The hypercholesterolemic students had larger Rohrer's indexes since entrance into elementary school and had earlier growth spurts as well as slow downs of body growth and earlier onsets of menarche than normo- or hypocholesterolemic students.

View full abstract

The purpose of the present study was to evaluate whether lactate threshold (LT) in rats could be detected from changes of blood lactate concentration during intensive graded exercise (IGE) with 2 protocols and prolonged exercise (PE) using motor driven treadmill. Rats used in this study were male and female Wistar strain rats 5 weeks of age. After running for 10 minutes per day for 1 week, IGE test was performed with 6 to 7 week old rats. Experimental periods for PE test ranged from 7 to 9 weeks old. Although blood lactate concentration during IGE test was exponentially increased, formal LT was hard to determine. In PE at speed of 23m/min, blood lactate concentration initially increased, and thereafter stablized or gradually decreased to the resting level. At this speed, rats could well tolerate running for 60 minutes. But, blood lactate concentration during PE at speed of 28m/min linearly increased with lapse of time. Endurance time at this speed and peak blood lactate value averaged 38 minutes (30-44 minutes) and 7.0mM (6.2-7.5mM), respectively. From these results, we estimated that the velocity corresponding to LT in rats 6 to 9 weeks of age was about 23m/min.

View full abstract

The terminal hexapeptide (residues 56-61) and α fragment (residues 30-61) of human metallothionein II (MT-II) were synthesized, labelled with ¹⁰⁹Cd and used to examine the relationship between the portions of reabsorption at the proximal tubules and the chemical forms of Cd administered into the rat. Cd was transported to the kidneys with 2.7%, 3.0% and 6.0%, 8.2% of the dose at 30min and 8h, respectively, after the administration of ¹⁰⁹Cd-hexapeptide and ¹⁰⁹Cd-α-fragment containing 0.13μmol/Cd/kg b. w. i. p. These renal uptakes of ¹⁰⁹Cd were much smaller than that of MT (15%)⁷⁾, although they were greater than that of the free ion (CdCl₂). The renal autoradiographical pattern due to ¹⁰⁹Cd was similar to the two complexes at 30min and 8h. The area of ¹⁰⁹Cd accumulation in the cortex was located in the convoluted portion of the proximal tubules. These findings showed that both Cd-peptides behaved in the same way as ¹⁰⁹Cd-MT in rats^{13, 16)}.

View full abstract

The present study was conducted to clarify the relationship between the humoral immune response and the concentration of beryllium (Be) in the blood and in the spleen of mice.
Mice were intraperitoneally injected with 0.075, 0.15, 0.3 or 0.6mg BeCl₂/kg body weight (1/80, 1/40, 1/20, 1/10 of the LD₅₀ for i. p. injection) every day for 2 weeks. The humoral immune response was determined by measuring the IgM or IgG-plaque forming cells (PFC) in the spleen using sheep red blood cells (SRBC) as antigen. The Be concentration in the blood and in the spleen was measured by flameless atomic absorption analysis.
The changes of the antibody production in the spleen to SRBC and the Be concentration in the blood and in the spleen of mice were studied throughout the 10 day period after stopping the Be injections. The following conclusions from the study were obtained:
1) It was recognized that the IgM or IgG-PFC to SRBC in the spleen of mice injected with Be increased when the Be concentration in the blood was kept between 5 and 35ng/ml, and decreased when the level was over 35ng/ml.
2) A relationship between the change of the IgM or IgG-PFC to SRBC and the Be concentration in the spleen was not recognized.
It is suggested that the adjuvant activity of beryllium on the humoral immune response is related to the concentration of beryllium in the blood.

View full abstract

Urinary excretion of N-acetyl-β-D-glucosaminidase (NAG), a lysosomal enzyme localized in the proximal tubular epithelial cells, has been reported to increase in subjects having renal tubular injury. In the present study, excreted amounts of β₂-microglobulin (β₂-mg), an established indicator of proximal tubular dysfunction, and NAG were determined in urine specimens from people living in cadmium (Cd)-polluted areas in Izuhara, Nagasaki prefecture (male, 136; female, 180) and in non-polluted areas in Ibaraki prefecture (male, 158; female, 140), and their usefulness as indicators of renal damage caused by environmental Cd exposure was compared. Subjects of each sex were divided into groups by every 10 years of age. In the non-polluted areas, urinary β₂-mg concentration was almost constant among all age groups, whereas NAG activity was elevated in age groups over 60 years old. Urinary β₂-mg concentration and NAG activity of female subjects in the Cd-polluted areas were higher than those in the non-polluted areas in age groups over 50 and 40 years old, respectively. In the polluted areas, number of subjects who excreted abnormally high amounts of urinary β₂-mg was sharply increased when urinary Cd exceeded a certain level, while urinary NAG activity was almost linearly elevated with increase in urinary Cd concentration. The incidence of abnormal values of urinary NAG activity in people living in the polluted areas was higher in age groups below 60 years old and was lower in age groups over 60 years old than that of urinary β₂-mg concentration. These results suggest that urinary NAG activity reflects renal effects of Cd in a more sensitive manner than urinary β₂-mg concentration at an earlier stage of renal damage, but that in a more advanced stage the renal damage is more markedly indicated by the increased level of β₂-mg concentration than that of NAG.

View full abstract