Geographical variations in the concentration of biliary free fatty acids with anti-mutagenic action.

The concentrations and compositions of free fatty acids (FFAs) in human bile, especially of inhibitory free fatty acids (IFFAs), were analyzed in terms of anti-mutagenic effects in relation to the mutagenic activity of bile. Bile samples were collected from patients with cholelithiasis residing in either Niigata or Kochi prefectures of Japan, regions characterized as the highest and lowest risk areas for gallbladder cancer (GBC), respectively. Biliary FFAs and IFFAs were analyzed by high-performance liquid chromatography and mutagenicity was examined in by the Ames test (TA98+S9mix) after blue rayon treatment. There was a tendency for higher biliary FFA and IFFA concentrations in the Kochi subjects, but the proportion of IFFA to the total FFA concentration did not differ between the two areas. There was an inverse correlation between the concentrations of IFFAs and the numbers of revertant colonies in both Niigata and Kochi subjects. However, at a dose of 591 micromol/l, (calculated based on the average amount of IFFAs absorbed in blue rayon) IFFAs did not exhibit anti-mutagenic actions in the blue rayon extracts. Within this range, more positive samples were seen in Niigata than in Kochi, suggesting the presence of more active mutagen(s) in Niigata samples.

Cholinesterase activity in quails of neuropathy caused by organophosphates.

It is known that some organophosphates produce not only well-known acute toxicity but also characteristic delayed neurotoxicity. Tri-ortho-tolyl phophate (TOTP), which was formerly named Tri-ortho-cresyl phosphaete (TOCP), was first noticed in an incident of poisoning as the compound which produced organophosphate induced delayed neurotoxicity (OPIDN). It is said that triphenyl phosphite (TPP) is also one of the organophosphates which possesses OPIDN. However, it is thought that TPP-induced delayed neurotoxicity (TPP-DN) is not identical with classical OPIDN. An intermediate syndrome was later proposed as the third neurotoxicity caused by organophosphates. We think that TPP is a model chemical of the third neurotoxicity. We compared TOTP with TPP using Japanese quails. We measured cholinesterase (ChE) activity and clearly demonstrated the difference between the two chemicals, that is to say, the activity recovered after 72 hrs from the administration of TPP, whereas the inhibition continued for more than 11 days after the administration of TOTP.

Comparison of mutagenic activity of bile between Chilean and Japanese female patients having cholelithiasis.

The mutagenic activity of bile was compared between Chilean and Japanese female patients having cholelithiasis by the Ames assay using Salmonella typhimurium tester strain TA98 in the presence of S9 mix with blue rayon adsorption technique. A reason for conducting the present investigation is that Chile and Japan have the highest mortality rates for the gallbladder cancer (GBC) in the world. Of 24 bile samples collected in Chile, 20 (83.3%) samples showed mutagenicity. In the case of Japanese bile, 21 (80.8%) of 26 and 5 (19.2%) of 26 cases were mutagenic in samples from high- and low-risk areas for GBC, respectively. Therefore, both the Chilean and the Japanese samples collected in high-risk areas showed higher mutagenic rates than the Japanese ones in a low-risk area, with a statistical significance (p < 0.001), chi-square test). The average number of revertant colonies were 128 +/- 92 (mean +/- SD), 62 +/- 14 and 66 +/- 13, respectively, when the blue rayon extracts of 200 microliters bile were applied to the Ames test. Thus, Chilean bile had a tendency to show a higher mutagenic activity than Japanese.

Chronic effect of aluminium ingestion on bone in calcium-deficient rats.

In order to elucidate the relationship of osteogenesis with aluminum and iron deposition, we investigated the histopathological findings of bone in calcium and/or aluminium-deficient rats, together with levels of calcium, aluminium and iron in sera and bone tissues, and also the level of serum parathyroid hormone. Four week old male STD-Wistar rats were divided into four groups to examine the effects of four kinds of diets for ten weeks. The rats on normal diet (Group I) and normal diet+aluminum (Group II) did not show any pathological changes of the bones, but in both calcium-deficient diet group (Group III) and calcium deficient diet added aluminium (Group IV), the compact bone converted into spongy bone in varying degrees, particularly in Group IV. Aluminium deposition was demonstrated at the calcification fronts and the cement lines only in Group IV as red or violet-red lines with aluminium stain, together with iron deposition as revealed with Berlin blue stain, showing similar distribution pattern as aluminum. It was clearly indicated that aluminium and iron, instead of calcium, deposited on the calcification front of the bone under the condition of calcium deficiency, inhibiting the normal osteogenesis.

Geographical variations in mutagenicity of blue rayon extracts of Japanese human bile.

The mutagenicity of human bile was investigated in the Ames test after blue rayon treatment. In the present study, 52 and 59 bile samples were collected from the high and the low risk population for gallbladder cancer (GBC), respectively. The bile mutagenicity was detected only when the blue rayon extracts of bile were assayed with Salmonella typhimurium TA98 in the presence of S9 mix. Thirty-two (61.5%) of 52 samples obtained from the high risk population were mutagenic. In our previous study (Mano et al., 1993), the mutagenicity was observed in 14 (58.3%) of 24 samples. After combining this data with the results of the present study, 46 (60.5%) of 76 samples revealed the mutagenicity. On the other hand, the mutagenicity was detected in only 7 (11.9%) of 59 samples collected from the low risk population. Therefore, we found a significant geographical difference in the bile mutagenicity.

[The effects of calcium deficiency on aluminum accumulation in the tissues of rats treated by oral aluminum administration].

We carried out this investigation to elucidate the effect of calcium (Ca) deficiency (Ca (-)) on aluminum (Al) accumulation in tissues of rats treated by oral Al administration. Thirty-two four-week-old rats (65g) were divided into two groups; a normal (N) diet group and a Ca (-) diet group. The N diet group was fed the N diet for 45 consecutive days, and then divided into four groups. Group (G)-1 rats were fed normal diet (N) for 9 days, G-2, G-3 and G-4 rats were fed an Al-overloaded N diet (1mg Al/g diet) for 3, 6 or 9 days, respectively. The Ca (-) diet group was fed Ca (-) diet for 45 consecutive days, and then divided into four groups. G-5 rats were fed the Ca (-) diet for 9 consecutive days, G-6, G-7 and G8 rats were fed an Al-overloaded Ca (-) diet for 3, 6 or 9 days. We studied the accumulation of Al in Ca- deficient rats fed Al (Ca (-) + Al) for 3, 6, and 9 days, comparing that of the normal- diet rats fed Al (N + Al) for the same period. The Al concentration in the small intestine increased on the third day after Al, and then decreased to the normal level on the 6th day in both N + Al and Ca (-) + Al rats. However, that of the Ca (-) + Al rats increased significantly compared to N + Al rats on the 9th day.(ABSTRACT TRUNCATED AT 250 WORDS)

Mutagenicity of blue rayon extracts of human bile in the Ames test.

The mutagenicity of human bile was examined in the Ames Salmonella/microsome assay. Bile samples were obtained from the gallbladders resected from patients with cholelithiasis, choledocholithiasis, gallbladder cancer, extrahepatic bile duct cancer and other diseases. For extraction of mutagenic components, the bile samples were treated with blue rayon and the adsorbed materials were assayed with Salmonella typhimurium TA98 in the presence of S9 mix. Twenty-four bile samples were tested and positive mutagenic activity was found in 14 samples. A 200-microliter bile equivalent material gave 6.3 times as many revertant colonies as the solvent control. With several samples that had undergone two cycles of blue rayon extraction, clear dose-response relationships in mutagenicity were demonstrated.

Effect of age and sex on copper-induced toxicity in the macular mutant mouse. An animal model for Menkes' kinky-hair disease.

It was determined if the sensitivity in macular mutant mouse to copper-induced toxicity was affected by sex or age. The sensitivity in 6-8-d-old or 3-4-wk-old macular mutant mouse to copper-induced toxicity was not affected by sex. However, 8-9-wk-old mutant females were more sensitive to copper-induced toxicity than mutant males. Furthermore, 6-8-d-old or 3-4-wk-old mutant males were more sensitive to copper-induced toxicity than 8-9-wk-old mutant males. However, age-related differences in sensitivity to copper-induced toxicity did not occur significantly in mutant females. On the other hand, in the case of normal mice, the sensitivity in 6-8-d-old or 3-4-wk-old mice to copper-induced toxicity was not also affected by sex. In contrast to mutant, however, 8-9-wk-old normal males were more sensitive to copper-induced toxicity than 8-9-wk-old normal females. Adult males were also more sensitive to copper-induced toxicity than 6-8-d-old or 3-4-wk-old males. However, age-related differences in sensitivity to copper-induced toxicity did not occur significantly in normal females. These results indicate that sex- and age-related differences in the copper-induced toxicity exist in macular mutant mice.

Intracellular distribution of hepatic copper in macular mutant mice. An animal model of Menkes' kinky-hair disease.

To evaluate the role of lysosomes in copper-mediated hepatocellular injury, copper was administered, sc, to both normal and macular mutant mice at doses of 4.5, 9.0, and 18 mg Cu/kg, and the subcellular distribution of copper has been investigated in the liver of normal and mutant mice 24 h after injection. The amount of copper in all fractions of copper-treated mutant mice was markedly lower than those in copper-treated normal mice, with the exception of microsomal fraction. However, there were no distinct differences in the proportion of copper in subcellular fractions between normal and mutant mice.

Copper-induced toxicity in macular mutant mouse: an animal model for Menkes' kinky-hair disease.

These studies were designed to determine if macular mutant mouse, which is a proposed animal model of Menkes' kinky-hair disease, is sensitive to the acute toxic effect of Cu as compared to normal and heterozygote mice. Single sc injection of Cu were administered to 6- to 8-day-old mice, and mortalities were recorded for 30 days. The copper treatment at high doses (12 to 25 mg Cu/kg) was very toxic to mutant mice as compared to normal mice, and almost all mutant mice died within 10 days after injection. The effect of Cu toxicity on heterozygote mice was intermediate. The LD50 values 3 days after injection of Cu were 29.5 mg Cu/kg for normal mice, 23.5 mg Cu/kg for heterozygote mice, and 15.5 mg Cu/kg for mutant mice. In Cu-injected mutant mice (11 and 18 mg Cu/kg), significant elevations in serum aspartate aminotransferase and lactate dehydrogenase activity occurred as compared to Cu-injected normal and heterozygote mice. However, no significant elevations in serum creatinine and urea nitrogen contents in Cu-injected mutant were observed as compared to normal and heterozygote mouse. No significant differences in hepatic metallothionein(MT) and MT-1 mRNA, and serum ceruloplasmin oxidase activity levels were observed between Cu-injected normal and mutant mouse. These results indicated that macular mutant mice was sensitive to the acute toxic or hepatotoxic effects of Cu as compared to normal and heterozygote mice.

Metallothionein messenger RNA levels in the macular mutant mouse: an animal model of Menkes' kinky-hair disease.

Levels of metallothionein-1 (MT-1) messenger RNA (mRNA) in various tissues from normal and macular mutant mice at different stages of development (17 days of gestation, 1-, 3-, 7- and 14-day-old) were determined by Northern blot analysis. Renal MT-1 mRNA levels in mutant mice were slightly elevated at 3 stages compared to normal mice, with the exception of mutant fetus and 3-day-old mutant mice. Intestinal MT-1 mRNA levels in mutant mice were elevated at 3 stages compared to normal mice with the exception of mutant fetus and 3-day-old mutant mice. Hepatic MT-1 mRNA levels in mutant fetus and 1-day-old mutant mice were approximately the same compared to normal mice. In 3- and 7-day-old mutant mice, hepatic MT-1 mRNA levels were depressed and in 14-day-old mutant mice, they were increased compared to normal mice. Brain MT-1 mRNA could not be detected in normal and mutant mice at the 4 stages with the exception of 14-day-old mice. MT-1 mRNA in 14-day-old mice was detected and the level of that in mutant mice was slightly elevated compared to normal mice. After injection of Cu, MT-1 mRNA levels in kidney, liver and intestine were determined. The injection of Cu increased the level of MT-1 mRNA in the tissues of normal and mutant mice compared to control (saline-injected) mice. Significant differences in MT-1 mRNA levels in the tissues of both Cu-injected mice were not observed.

Selenium contents in human gallbladder bile.

The selenium contents in human gallbladder bile were analyzed. Thirty-seven subjects were studied; 22 patients with cholelithiasis in Niigata Prefecture and 15 patients (13 with cholelithiasis and 2 with gallbladder polypus) in Kochi Prefecture. Five ml of bile was withdrawn with a syringe from the gallbladder during the operation and stored at -20 degrees C until analysis. For the analysis by gas chromatograph with an electron-capture detector, 0.2 ml of sample was used. The mean selenium contents in bile were 269 +/- 39.0 (mean +/- S.D.) ng/ml for the subjects in Niigata and 285 +/- 84.4 ng/ml in Kochi; without significant difference. Of 37 samples analyzed, the mean content was 276 +/- 61.0 ng/ml.

Stimulation of cadmium uptake by estradiol in the kidney of male rats treated with cadmium.

The present study was carried out to analyze the sex differences in the retention of Cd in rats treated with a small amount of Cd, and its mechanisms. Cd and Zn concentrations in the kidney and liver of female rats treated with 28 nmol Cd or 1 nmole Zn were significantly higher than those in male rats. Pretreatment with estradiol (1.8 mumol/kg of b.w., twice a day, 6 consecutive days) increased the Cd and Zn concentrations in the kidney of male rats treated with Cd or Zn. Incubation of MDCK cells with 10(-5) M estradiol, 10(-5) M stilboestrol and 10(-5) M progesterone caused a significant increase in Cd uptake. These results suggest that endogenous female sex hormones may play a role in a higher concentration of Cd and Zn in the kidney of female rats than that in male rats. The basal level of metallothionein (MT) in the liver and kidney of control female rats was within the same range as that in the control male rats. Cd and Zn accumulations caused by pretreatment with estradiol in the kidney of male rats treated with Cd or Zn were so low (Cd: 38 ppb, Zn: 1.0 ppb) as to be probably unable to induce the synthesis of MT. An increase in the concentration of Cd in the cultured renal cells occurred 1 hr after treatment with estradiol and Cd. Pretreatment with estradiol alone also resulted in a modification of the concentration of Na and K, which cannot be bound to MT. Together, all of the above findings suggest that estradiol directly increases the accumulation of Cd into the renal cells without inducing the synthesis of MT.

Delayed neurotoxicity resulting from administration of leptophos to the comb of domestic fowl.

We investigated the occurrence of delayed neurotoxicity in domestic fowl following percutaneous application of leptophos. Five groups of 5 adult hens received daily percutaneous doses of 1.0 ml/hen of leptophos emulsion (leptophos; 340 mg/hen/day) for 2, 5, 10, 15 or 20 days. There was no abnormal gait in the 2-day group. Two out of 5 hens in the 5-day group showed mild ataxia from about 2 weeks after the final administration, but did not develop severe neuropathy. On the contrary, 4 out of 5 birds in the 10-day group and all hens in the 15- and 20-day groups were affected by various stages of neurotoxicity. Some of them died from neurotoxicity. Ten of young male chickens were given the same dermal dose for 5 or 10 days. Although no abnormal chicken was observed in the 5-day group, all chickens in the 10-day group showed severe paralysis and two of them died. We studied the incidence rates of delayed neurotoxicity resulting from respective applications of the emulsion and the acetone solution of leptophos. No significant difference was observed between them. These results suggest that the daily dermal application of the relatively high dose of leptophos, even if for the short term, can cause the same delayed neurotoxic effects as by the oral administration in hens or chickens.

Rotavirus infection in children with acute gastroenteritis in Ecuador.

Electron microscopic examination of stools of 702 infants and young children hospitalized in the Emergency Service of the Alejandro Mann Children's Hospital in Guayaquil, Ecuador, between August 1978 and October 1979 showed rotavirus to be present in 148 (21.1%). During the study period rotavirus was detected throughout the year, with no distinct seasonal variation. In addition to rotavirus, adenovirus was detected in stools of five (0.7%) of the patients and unidentified small round virus particles in seven (1.0%).

Neurotoxicity by the dividing administration of critical dose of phosvel.

Phosvel, an organophosphorus insecticide, produces delayed neurotoxicity in hens. A change in the toxicity, and in the residue of insecticide in the fat, were observed when the critical dose which was demonstrated in the case of a single dose was subdivided.

Accumulation of Phosvel in adipose tissue of hens.

Phosvel, an organophosphorus pesticide, was stored in the adipose tissue of hens after they were given daily a single oral dose. The concentration of Phosvel in fat was related to the size of the daily dose.