In the blood of 15 patients with yusho or "polychlorinated biphenyl poisoning" that occurred in 1979 in Taiwan, was found polychlorinated dibenzofurans (14 of 15) and polychlorinated quaterphenyls (15 of 15), as well as polychlorinated biphenyls (15 of 15). The mean concentration ratio of these substances was approximately 1 : 160 : 500. Based on the following evidence, we propose that polychlorinated quaterphenyls were major pathogenic substances in the development of yusho: (1) Clinical manifestations and course of yusho patients are disproportionately severe and persistent for the observed blood levels of polychlorinated biphenyls, while patients who were occupationally exposed to pure polychlorinated biphenyls take characteristically mild and benign clinical course despite polychlorinated biphenyl levels often much higher than those noted in yusho patients; (2) Polychlorinated debenzofurans show a marked tendency to accumulate in the liver, which might explain frequent presence of jaundice and other abdominal symptoms in yusho, which are, again, not observed in those with occupational polychlorinated biphenyl poisoning; (3) Toxicity of polychlorinated dibenzofurans is a hundred to ten thousand times greater than that of polychlorinated biphenyls and polychlorinated quaterphenyls in animal experiments.

Benzofurans↗

PubMedDate not supplied

Transmission of the nucleic acid-induced character, caudal fin, to the offspring in goldfish.

The carp's egg-mRNA and DNA induced, single-tail-finned goldfish were used for mating. The offspring developed double, single and modified single tail fin. The combined frequency of the single and modified single tail fin formation in the mRNA-and DNA-injected series were 39.6% and 38.3% respectively. The corresponding frequency of the control series was 3.8%. These results show that the exogenous mRNA and DNA have altered the tail fin formation not only in the goldfish developed from the injected eggs but also in their offspring.

Animals↗

PubMedDate not supplied

Genetic manipulation in higher organisms. I. Goldfish ova as materials of operation, mRNA mediated alteration of the liver specific isozymes.

Both crucian and carp egg-mRNAs were found to mediate the transformation of goldfish tail from the double (veil-shaped) to the single (fork-shaped). Livers of these single tailed goldfish were tested for genetic change using lactate dehydrogenase isozymes (LDH) as marker. Electrophoresis of liver extracts on starch gel showed that the liver specific LDH-C4 isozymes of both the egg-mRNA and liver-mRNA injected goldfish resembled the control goldfish except an additional intermediate band. The migration distance of this new band matched the third band of the hybrids (carp X goldfish). These findings lead to the conclusion that carp egg-mRNA contains a fraction partly responsible for liver development. Rat liver was found possessing the cathodally migrating C4 isozymes. Injection of rat liver-mRNA into goldfish eggs resulted in the intensification of the liver specific C4 isozymes. It appears therefore that the input informational molecules (liver-mRNA) and the output molecular products (liver C4 isozymes) are causally related. This causal relationship would pave the way for genetic manipulation in higher organisms.

Animals↗

PubMedDate not supplied

Organ formation caused by nucleic acid from different class.--Urodele DNA mediated balancer formation in goldfish.

DNA was isolated from visceral organs of urodele and injected into fertilized eggs of goldfish. Approximately 1% of the young fish developed one balancer. From gross and microscopical structures, site of development, and nature of absorption, it resembles the balancer of urodelian species.

Animals↗

PubMedDate not supplied

The effect of carp EGG-mRNA on the transformation of goldfish tail.

Poly A attached mRNA was prepared from carp's mature ovarian eggs. When injected into fertilized eggs from different strains of goldfish, it mediated tail transformation from the double to single. The frequency varied according to the strain of goldfish. This discovery provides new information not only supporting but also expanding the previous report that crucian egg-mRNA mediated tail transformation in goldfish.

Animals↗