Cytogenetic disorders in peripheral blood lymphocytes of patients with febrile form of tick-borne encephalitis.

An appreciable increase in the number of aberrant lymphocytes was detected in the peripheral blood of patients with febrile form of tick-borne encephalitis (TBE). This increase peaked during week 2 of the infectious process and was paralleled by a decrease in the count of natural killer cells. By the end of the acute period of neuroinfection the number of cells with structural chromosome aberrations decreased, but still surpassed the control (donor blood).

Coat protein sequences of RMV-like strains of barley yellow dwarf virus separate them from other luteoviruses.

Illinois (IL) and Minnesota (MN) RMV-like strains of barley yellow dwarf virus (BYDV) were identified from maize displaying red leaf symptoms by enzyme-linked immunosorbent assay (ELISA) using antiserum against a New York strain (BYDV-RMV-NY). Some IL and MN strains, but not the NY strain, could be detected by ELISA with a monoclonal antibody raised against BYDV-RPV-NY. The region of the viral genome representing the coat protein gene was amplified by polymerase chain reaction, cloned and sequenced.

Expression strategy of the potato virus X triple gene block.

The mode of expression of the overlapping genes of the triple block positioned internally in potato virus X (PVX) RNA was examined. The results of In vitro translation of synthetic RNA transcripts and natural PVX-specific methylmercuric hydroxide-denatured dsRNAs suggest that the 25K protein is expressed as a single translation product of the 2.1 kb subgenomic (sg) RNA and that both the 12K and 8K proteins are expressed from the same 1.

In vitro membrane binding of the translation products of the carlavirus 7-kDa protein genes.

Two double-stranded DNA copies of the genes potentially coding for the 7-kDa proteins of potato virus M (PVM) and potato virus S (PVS) were synthesized and cloned into T7 transcription vectors. Cell-free translation of the corresponding monocistronic transcripts yielded in both cases a single protein of approximately 7-8 kDa that contains a highly hydrophobic N-terminal segment. To analyze their membrane-binding potential, both proteins were synthesized in the membrane-enriched Krebs-2 extract.

Expression of RNA transcripts of potato virus X full-length and subgenomic cDNAs.

Translation of synthetic potato virus X (PVX) RNAs was examined in Krebs II ascite cell extracts and rabbit reticulocyte lysates. Either full-length or subgenomic RNAs produced by in vitro transcription of cDNAs cloned in the T7 promoter vectors were used. Full-length PVX RNA-transcript directed the synthesis of a large polypeptide which was indistinguishable from the translation product (165 kDa) of authentic viral genomic RNA on SDS-PAGE.

[Nucleotide sequence and structural organization of the 3'-terminal region of potato virus M].

The sequence of 2630 3'-terminal nucleotides has been determined for the genomic RNA of potato virus M (PVM), a type member of the carlavirus group. Analysis of this nucleotide sequence revealed five open reading frames coding for proteins of mol. wt.

Conserved and variable elements in RNA genomes of potexviruses.

The nucleotide sequences of genomic RNAs and predicted amino acid sequences of two strains of potato virus X and white clover mosaic potexvirus were compared to each other, and the proteins of different plus-RNA-containing plant viruses. The predicted non-virion proteins of potexviruses have direct sequence homology and common structural peculiarities with those of several 'Sindbis-like' plant viruses. The most conserved amino acid sequences were found to be located in the polypeptide encoded by the long 5'-proximal open reading frame (ORF1).

[Primary structure of the potato virus X genome: the region preceding the capsid protein cistron].

DNA copies of the potato virus X (PVX) RNA corresponding to 2300 nucleotides at the 3'-end have been cloned. The cloned cDNA copies containing the nucleotides 445-1280 from the 3'-end have been sequenced. The 5'-terminal region of the PVX coat protein gene corresponds to residues 445-786 from the 3'-end.

[Salmonella typhimurium--test system for detecting the mutagenic activity of environmental pollutants. II. Mutagenic effect of heavy metal salts in an in vitro system with metabolic activation].

Mutagenic effect of zinc chloride on Salmonella typhimurium strain was detected using in vitro metabolic activation system. Cadmium chloride showed no significant mutagenic activity in the same system. It is recommended to use both in vitro and in vivo metabolic activation systems in mutagenicity testing of chemicals.

[Salmonella typhimurium as a test system for detecting the mutagenic activity of environmental pollutants. I. The mutagenic action of heavy metal salts in in vivo and in vitro systems without metabolic activation].

The work presents the data on mutagenic effects of heavy metal salts (Zn and Cd) on Salmonella typhimurium test strains using mutagenicity test in vitro without metabolic activation and host-mediated assay. The techniques used enabled to determine also the types of mutations arising from the exposure to ZnCl2 and CdCl2.