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Biomedical subjects

G Conti

Publications and source records attributed to G Conti.

At least 163 records · Page 9Linked to original sources
PubMed1980

Different patterns of replication in influenza virus-infected KB cells.

When KB cells were infected either with the fowl plague (FPV) Rostock strain (Hav1N1) or the WSN (H0N1) strain of influenza A virus the yield of cell-associated haemagglutinin and neuraminidase polypeptides was essentially comparable, but virus particles were not produced in the FPV-KB system. WSN virus-infected KB cells synthesized normal amounts of mature virus particles and had all the characteristics of a permissive replication cycle. Biosynthesis and transport of RNP antigen from nucleus to cytoplasm of infected cells were traced by immunofluorescent staining at 4 and 8 hours after the beginning of infection. While the fluorescent-stained material was totally confined to the nuclei in FPV-infected KB cells, RNP antigen migrated out of the nucleus during the replicative cycle of WSN virus in the same host cell. Patterns of virus-specific protein synthesis were studied by pulse-labelling with 35S-methionine. The most significant feature concerned the amplification of synthesis of virus-induced matrix (M) protein which did not occur in FPV-infected cells but occurred normally during WSN infection. The different patterns of replication in the same host cell when infected by different influenza A viruses is discussed.

Cell Line↗
PubMed1980

Mutagenicity of halogenated aliphatic hydrocarbons in Salmonella typhimurium, Streptomyces coelicolor and Aspergillus nidulans.

Eight structurally related halogenated aliphatic hydrocarbons mono-, di- and trichloroacetaldehyde (the last in the anhydrous and hydrate form), moni-, di- and trichloroethanol and allyl chloride, were tested for their ability to induce gene mutations in prokaryotic and eukaryotic microorganisms. The genetic systems employed were the Salmonella reversion test with strain TA1535 and TA100, with and without metabolic activation, a forward and a back-mutation system in S. coelicolor and two forward mutation systems in A. nidulans. Each compound was tested with the spot and plate incorporation assay techniques. Mono-, di- and trichloroacetaldehyde were mutagenic in all the microorganisms employed; all the halogenated ethanols were positive in A. nidulans, while in S. typhimurium and in S. coelicolor the only active forms were respectively the mono- and dichloroderivatives. Allyl chloride was active in S. typhimurium and S. coelicolor and negative in A. nidulans. The technical approach as well as the complex influence of different factors (toxicity, volatility and stability) on the genetic response of each of the compounds under test did not allow to obtain more than a qualitative relationship between mutagenic potency and chemical structure.

Animals↗
PubMed1980

[Phosphorylation of viral polypeptides in cells infected with influenza virus].

Experiments carried out in vivo with WSN (H0N1) and FPV (Hav1N1) strains of influenza virus have shown the presence of phosphorylated virus-induced polypeptides. Notably it was interesting the behaviour of the non-structural NS1, NP nucleoprotein and membrane M viral components whose phosphorylation was different among the cellular hosts tested. In in vitro experiments we were able to demonstrate a protein-kinase-activity in purified virions. The similarities and differences found in vivo and in vitro systems are discussed taking into consideration the fact that viral replicative cycle is closely dependent from the cellular host and the pattern of influenza virus infection is unique between different hosts.

Orthomyxoviridae↗
PubMed1980

Effects of estrogens P-1496 and P-1560 on the binding of estradiol with rat uterine estrogen receptors.

The interference of two weak estrogens (P-1496 and P-1560) on the binding of estradiol with uterine estrogen receptors is comparatively studied. Both P-1496 and P-1560 decrease the estradiol binding capacity, but P-1560 is less effective than P-1496. Since P-1496 is a more potent estrogenic substance than P-1560, the results obtained confirm that the uterotrophic activity of estrogens is related to the binding capability to uterine estrogen receptors.

Animals↗
PubMed1979

Mutational studies with diquat and paraquat in vitro.

Diquat and paraquat were assayed in the following tests. (1) Ames test in Salmonella typhimurium (strains TA1535, TA1537, TA1538, TA98 and TA100) with and without rat-liver microsomal fractions. (2) Resistance to 8-azaguanine in Salmonella typhimurium (strain hisG46, TA92 and TA1535. (3) Repair test in Salmonella typhimurium (strains TA1538 and TA1978). (4) Gene mutations in Aspergillus nidulans: 8-AG resistance and methionine suppression (meth A1 locus). (5) Lethal recessive damage in Aspergillus nidulans. (6) Unscheduled DNA synthesis (UDS) in human epithelial-like cells (EUE). Diquat and paraquat were positive in S. typhimurium (in the repair test and the 8-AG resistance system), in A. nidulans (for gene mutations and lethal recessive damage induction) and in EUE cells (UDS induction).

Animals↗
PubMed1979

A new in vitro method for testing plant metabolism in mutagenicity studies.

A rapid method was proposed to detect whether a harmless agricultural chemical can be converted into a mutagenic one by plant metabolism. The method is based on the use of Nicotiana alata cell cultures. Results obtained with five pesticides (atrazine, dichlorvos, tetrachlorvinphos, Kelevan, and maleic hydrazide) suggest that the proposed method simulates the metabolism of the whole plant. This procedure was also successfully applied to the genetic system of Aspergillus nidulans. One pesticide, atrazine, induced mutations and somatic segregation only after metabolism during cocultivation with N. alata cells.

Atrazine↗
PubMed1979

In vitro generation of nonspecific suppressor cells and their characterization.

In vitro preculture of C3H/He splenocytes for 48 to 96 hr induces aspecific suppressor cells evaluated by their ability to reduce 3H-TdR uptake by fresh syngeneic splenocytes stimulated by different amounts of Concanavalin A (Con A) in vitro. This suppressive activity is obtained in medium containing 10% heat-inactivated fetal calf serum (FCS) or similar amounts of heat-inactivated bovine serum, syngeneic, or allogeneic murine sera but not by unheated FCS. Suppressive activity is resistant to mitomycin C and radiation up to 5,000 R. Exposure of precultured cells to carbonyl iron or plastic adherence, but not to anti-Thy 1.2 serum plus complement, results in removal of the suppressive activity.

Animals↗
PubMed1979

[Reasons for treatment failures in carpal scaphoid fractures].

Are taken into examination the principal causes of mechanical, biological, anatomical order, of incorrect treatment to whom to give the evolution in pseudoarthrosis of scaphoid fractures and of unsuccess for their bloody treatment. Cases of insuccesses is presented for whom is tried to give to each one of them an etiopathogenetical explanation and the most recent techniques adopted are shown.

Adult↗
PubMed1978

[Plasma renin activity in hypertensive patients under basal conditions and in various postures: preliminary data].

We have studied PRA levels in 10 healthy subjects compared with 10 patients affected with essential hypertension (with low PRA) on venous blood samples collected after 8 hours of rest and after 15-20 minutes of slow plain walk. Contemporarely we have taken up arterious pression levels in each class of subjects of these studies. No significant differences of PRA are demonstrable in healthy subjects and in patients affected with essential hypertension. Postural changes in hypertension produces significant rise of PRA, not related to arterial pressure.

Adolescent↗
PubMed1978

[Oxoprenolol and plasmatic renin activity in essential hypertension: preliminary data].

We have studied PRA levels in 10 healthy subjects compared with 10 patients affected with essential hypertension (with low PRA) on venous blood samples collected after 8 hours of rest and after 15-20 minutes of slow plain walk and 15 minutes after intravenous administration of oxoprenolol (mg 2). Contemporarely we have taken up arterious pression levels in each class of subjects of these studies. Postural changes produces significant rise of PRA in subjects affected with essential hypertension, that is significantly inhibited by pharmacologic interference produced by beta-blocking agents. This occurrence is independent of arterial pressure changes.

Adult↗
PubMed1978

Microbiological titration of proteins and of single amino acid content in biological materials without purification and hydrolysis.

A method is described for the microbiological determination of the protein content of biological materials. This method can also be adopted to titrate the concentration of a single amino acid in the protein and has the following advantages: (1) titration can be done without purification and hydrolysis of proteins; (2) the titration graph is a straight line between 25 and 800 microgram/ml; (3) protein values agree with those obtained using the Kjeldhal method; and (4) each mutant requiring one amino acid may be used to titrate the concentration of a single amino acid of the protein. The leucine content of various kinds of flour was measured with this system.

Amino Acids↗