PubMed Health⌕ Search

Biomedical subjects

D J Picciano

Publications and source records attributed to D J Picciano.

12 recordsLinked to original sources
PubMed1979

Dominant lethality in frog embryos after paternal treatment with triethylenemelamine: cytogenetics, morphology, and swimming capability.

Male frogs (Rana pipiens) were injected intraperitoneally with triethylenemelamine (TEM). The injected males were held for seven days to permit TEM interaction with sperm. The TEM-treated males were then spermiated with human chorionic gonadotropin (HCG) and the ova of normal females were inseminated with the sperm. Direct observation was made of in vitro fertilized ova, cleavage, blastulation, and subsequent embryonic development. No differences were detected between the controls and treated animals from any experimental group for fertilization, cleavage, and blastulation. Dose-related morphologic abnormalities first became apparent at the time of gastrulation; the capability of hatched embryos to swim was affected by TEM. Metaphase chromosomes were studied from randomly selected embryos, and the prevalence of chromosomal structural abnormalities increased with dose over a range of 13--1,300 microgram TEM per kilogram frog.

Animals↗
PubMed1977

A short-term culture method for the preparation of chromosome spreads from Rana pipiens.

Chromosomes suitable for karyotyping were produced from short-term cultures of cells from embryonic northern leopard frogs, Rana pipiens, at various growth stages. Embryos were minced in a trypsin solution. The tissue fragments were subsequently cultured in an electrolytic solution containing fetal calf serum and Colcemid. We found this technique to be highly reproducible. In contrast to the conventional squash technique we were able to obtain a greater number of metaphase spreads suitable for identification and analysis of individual chromosomal aberrations.

Animals↗
PubMed1977

Vinyl chloride cytogenetics.

This report presents cytogenetic findings from a group of 209 workers employed for up to 28 years in the manufacture of vinyl chloride monomer at the Texas Division of Dow Chemical U.S.A. Cytogenetic evaluation results from this group were compared to results found in examination of individuals being considered for employment. Statistical analyses were performed on a group basis for chromatid aberrations, chromosome aberrations and proportion of abnormal cells; no statistical difference of significance was found between the two groups. Comparison of these results with reported studies suggests that the level of cytogenetic aberrations in vinyl chloride workers is probably related to the length and level of exposure, and that risk of adverse genetic effect can be avoided in controlled, minimal-exposure environments.

Chemical Industry↗
PubMed1976

Fertilization and development of frog eggs after repeated spermiation induced by human chorionic gonadotropin.

Sperm released into the urine of adult male frogs, Rana pipiens, after intraperitoneal injection of human chorionic gonadotropin, were used to fertilize freshly ovulated eggs. Repeated spermiations from the same animal were induced with repeated injections of the hormone at intervals of four to 11 days. Individual frogs were induced to spermiate up to four times, with fertile sperm ensuing each time. Development of zygotes produced by this method did not differ from the development of ova fertilized by conventional methods.

Animals↗
PubMed1975

alpha-and beta-Globin complementary deoxyribonucleic acids of human and rabbit. Specificity of hybridization.

The specificity of hybridization was compared between the human and rabbit alpha and beta-globin complementary DNAs (cDNAs) and the corresponding alpha and beta-globin messenger RNAs (mRNAs). The globin chain-specific mRNAs of rabbit were prepared from polysomes incubated with O-methylthreonine (alpha and beta) or from postribosomal supernatant (alpha). Enrichment for either the alpha- or beta-globin mRNA was demonstrated by cell-free protein synthesis and by RNA-cDNA hybridization. Human mRNAs, active as templates for RNA-directed DNA polymerase, were prepared from reticulocytes of patients with hemolytic anemia, alpha-thalassemia (hemoglobin H disease), and beta-thalassemia. Because there was partial cross-hybridization between human mRNA and rabbit cDNA, the rabbit alpha- and beta-globin cDNAs could be used to demonstrate that the beta-thalassemia mRNA was enriched in human alpha-globin mRNA sequences and that the alpha-thalassemia mRNA was enriched in human beta-globin mRNA sequences. These results were confirmed by preparation of thalassemia globin cDNAs and subsequent hybridization to their template mRNAs. The amount of cross-hybridization between the human and rabbit alpha-globin mRNA and the two alpha-globin cDNAs was comparable to the cross-hybridization between the two beta-globin mRNAs and the two beta-globin cDNAs, indicating a similar degree of evolutionary divergence in the nucleotide sequences of the two globin genes.

Animals↗
PubMed1974

Cell-free transcription of mammalian chromatin: transcription of globin messenger RNA sequences from bone-marrow chromatin with mammalian RNA polymerase.

A mammalian cell-free transcriptional system was developed in which mammalian RNA polymerase synthesizes globin messenger RNA sequences from bone-marrow chromatin. The messenger RNA sequences are detected by measurement of the ability of the transcribed RNA to hybridize with globin complementary DNA. The globin complementary DNA is synthesized by the enzyme from avian myeloblastosis virus, RNA-directed DNA polymerase, with purified globin messenger RNA as template. The specificity of the globin complementary DNA in annealing reactions was verified by preparing DNA complementary to liver messenger RNA and showing that the globin and liver complementary DNAs are specific for their own messenger RNAs. Both DNA-dependent RNA polymerase II from sheep liver and RNA polymerase from Escherichia coli can transcribe globin messenger RNA sequences from rabbit bone-marrow chromatin; however, the mammalian enzyme appears to be more specific in that globin gene sequences represent a higher proportion of the RNA synthesized. Neither polymerase can transcribe globin messenger RNA sequences from rabbit-liver chromatin. This cell-free assay system should be useful in searching for mammalian transcriptional regulatory factors.

Animals↗
PubMed1971

Translation of exogenous messenger RNA for hemoglobin on reticulocyte and liver ribosomes.

The ribosome and initiation factor requirements for translation of rabbit-reticulocyte hemoglobin mRNA on rabbit reticulocyte ribosomes, reticulocyte ribosomal subunits, and liver ribosomes have been studied. Excellent synthesis of globin chains from exogenous mRNA in the fractionated cell-free system has been achieved. There is a near absolute requirement for each of the initiation factors, M(1), M(2), and M(3) (as well as for the supernatant proteins) for the translation of exogenous mRNA. Liver microsomal wash will partially replace reticulocyte factors M(1) and M(2), but will not replace the requirement for reticulocyte factor M(3). Rabbit liver ribosomes and rabbit reticulocyte ribosomes are equally active in their ability to support the translation of exogenous hemoglobin mRNA.

Animals↗