[Retrospective analysis of the results of whole-body PET/CT as a possible tool for clinical examination of the population in order to identify subclinical manifestations of chronic kidney disease (pilot study)].

INTRODUCTION: Every year in Russia, more than 200 thousand whole body PET/CT are performed for various diseases in patients without clinical and laboratory manifestations of chronic kidney disease (CKD). However, only the "area of interest" of the attending physician is analyzed, while the rest of the organs or rather their metabolic activity is neglected during the standard procedure of this contemporary and high-tech research method. AIM: To perform a retrospective study of whole-body PET/CT as a tool for prophylactic clinical examination of the population in order to identify subclinical manifestations of chronic kidney disease MATERIALS AND METHODS: The results of whole-body PET/CT with 11C-choline were retrospectively analyzed for the detection of CKD in 100 patients of the Tyumen region who underwent a study for various indications outside the genitourinary system without history, clinical and laboratory manifestations of CKD. RESULTS: According to the results, 22% of patients had different manifestations of 11C-choline hypometabolism, indicating a decrease in the viability of the parenchyma. In 14% of patients, there was a local decrease in the uptake of 11C-choline without CT-signs of kidneys damage, and in 8% of cases there was a total decrease in their metabolism, coinciding with X-ray signs of renal scarring. CONCLUSIONS: The possibility of early molecular study of nephropathy can be used for wider retrospective PET/CT clinical examination as one of the highly effective methods for detecting CKD, which needs further research.

[Induced expression of Serratia marcescens ribonuclease III gene in transgenic Nicotiana tabacum L. cv. SR1 tobacco plants].

Transgenic Nicotiana tabacum L. cv. SR1 plants, characterized by an increase in the level of dsRNA-specific hydrolytic activity after induction by wounding, were obtained. The Solanum lycopersicum anionic peroxidase gene promoter (new for plant genetic engineering) was for the first time used for the induced expression of the target Serratia marcescens RNase III gene. Upon infection with the tobacco mosaic virus (TMV), the transgenic plants of the obtained lines did not differ significantly from the control group in the level of TMV capsid protein accumulation. In general, no delay in the development of the infection symptoms was observed in transgenic plants as compared with the control group. The obtained transgenic plants represent a new model for the study of the biological role of endoribonucleases from the RNase III family, including in molecular mechanisms of resistance to pathogens.

[Transgenic Expression of Serratia marcescens Native and Mutant Nucleases Modulates Tobacco Mosaic Virus Resistance in Nicotiana tabacum L].

Extracellular Serratia marcescens nuclease is an extremely active enzyme which non-specifically degrades RNA and DNA. Its antiviral activity was previously shown both in animals and in plants when applied exogenously. Transgenic tobacco plants (Nicotiana tabacum L cv. SR1) expressing S. marcescens chimeric, mutant, and intracellular mutant nuclease gene variants were regenerated and challenged with tobacco mosaic virus. The transgenic plants exhibited a higher level of resistance to the virus infection than the control non-transgenic plants. The resistance was evidenced by the delay of the appearance of mosaic symptoms and the retarded accumulation of viral antigen. Thus, these results reveal that modulations of both extracellular nuclease activity and intracellular RNA/DNA binding can protect plants against viral diseases.

[Analysis of transcriptional activity of the ornithine-delta-aminotransferase gene promoter in Arabidopsis thaliana].

Cloning of the Arabidopsis thaliana genomic DNA fragment presumably corresponding to the promoter region of the ornithine-delta-aminotransferase (OAT) gene is reported. The reporter-gene construct, containing the Escherichia coli beta-glucouronidase gene under control of the OAT gene promoter was generated. The Nicotian tabacum SR1 transformants carrying this construct were obtained. It was demonstrated that in normal conditions, expression of the reporter gene was associated with the meristems and the zones of intensive shoot growth. Possible role of the OAT gene in nitrogen metabolism and shoot development is discussed.

[Tobacco transformants expressing the Medicago truncatula ornithine aminotransferase cDNA].

The Medicago truncatula ornithine aminotransferase cDNA was cloned under the potent constitutive 35S RNA promoter of the cauliflower mosaic virus and transferred into the genome of tobacco Nicotiana tabacum SR1 plants. Transformed tobacco plants grew better in salinity stress, but did not differ in proline content under normal or stress conditions from control plants. It was assumed that the role of ornithine aminotransferase in the molecular mechanisms of stress resistance is not associated with additional proline synthesis.

[Silencing of the nk1 gene in the SR1 Nicotiana tabacum plants by RNA interference].

Primary transformants of SR1 Nicotiana tabacum plants with RNA interference-based silencing of the gene for extracellular ribonuclease Nk1 were constructed. It was demonstrated that the profiles of ribonuclease activities of leaf protein extracts from these plants lacked ribonuclease with electrophoretic mobility corresponding to that of the Nk1 protein. Primary transformants did not differ phenotypically from control plants. They represent a new model for investigation of the biological role of extracellular ribonucleases, including the molecular mechanisms of resistance to pathogens.

[Tobacco transformants expressing antisense sequence of proline dehydrogenase gene possess tolerance to heavy metals].

Analysis of resistance of genetically modified tobacco plants bearing antisense suppressor of proline dehydrogenase gene and characterized with higher content of proline to elevated concentrations of heavy metals was performed. It was demonstrated that progeny of transgenic plants have high resistance to lead, nickel and cadmium ions.

[Effective expression of the gene encoding an extracellular ribonuclease of Zinnia elegans in the SR1 Nicotiana tabacum plants].

Complementary DNA for the extracellular RNase of Zinnia elegans was cloned under control of the cauliflower mosaic virus 35S RNA constitutive promoter and transferred into the Nicotiana tabacum SR1 plants. Primary tobacco transformants were characterized by a high level of RNase activity.

[Evaluation of salt tolerance in Nicotiana tabacum plants bearing an antisense suppressor of the proline dehydrogenase gene].

We studied the stress resistance of genetically modified (GM) tobacco plants bearing an antisense suppressor of the gene for proline dehydrogenase. Such plants are characterized by elevated proline content. The progeny of the transgenic plants were shown to have elevated salt tolerance.