High-sensitivity express immunochromatographic method for detection of plant infection by tobacco mosaic virus.

A highly sensitive express immunochromatography method for molecular diagnosis of plant virus infections was elaborated on the example of a model object - tobacco mosaic virus (TMV). The analysis time does not exceed 5 min, and the lower limit of TMV detection in non-clarified leaf extract (2-4 ng/ml) is comparable with the sensitivity of the enzyme-linked immunosorbent assay of the virus. A single measurement requires 0.1-0.2 ml tested solution (extract from 10-20 mg of leaf material). The sensitivity of TMV determination in the leaf tissue extract was increased by more than one order of magnitude using signal enhancement by silver and is 0.1 ng/ml. In this case, analysis time did not exceed 25 min. The simplicity of this method makes it especially convenient in express diagnosis of numerous analyzed specimens. The prototype of a diagnostic kit for serial analyses of plant viral infections both in laboratory and field conditions was elaborated.

Complete sequencing of potato virus X new strain genome and construction of viral vector for production of target proteins in plants.

The complete nucleotide sequence of the genome of a new potato virus X (PVX) strain Tula isolated by us has been determined. Based on comparison of the PVX Tula nucleotide sequence with the sequences of 12 other PVX strains, this strain was assigned to the European cluster of PVX strains. Phylogenetic analysis revealed the same phylogeny for both full genome sequences and nucleotide sequences of polymerase and coat protein genes, suggesting that the PVX evolution did not involve recombination between different strains. The full-size cDNA copy of the PVX Tula genome was cloned and the accumulation of the viral coat protein in infected Nicotiana benthamiana was shown to be about twofold higher than for the PVX strain UK3. Based on the PVX Tula genome, a new vector which contained the target gene instead of the removed triple transport gene block and the coat protein gene has been constructed for expression of target proteins in plants. The productivity of the new vector was about 1.5-2-fold higher than the productivity of the vector of the same structure based on the standard PVX strain genome. The new viral vector can be used for superproduction of recombinant proteins in plants.

[Comparative study of structural stabylity of potato virus X coat protein molecules in solution and in the virus particles].

With help of several optical methods and differential scanning calorimetry we studied the structure and stability of molecules of coat protein (CP) of filamentous of potato virus X (PVX) in free state and in the virions. According to the results of all these methods, at room temperature (25 degrees C) free PVX CP subunits possess some fixed tertiary structure but this structure is highly unstable and is completely disrupted at temperatures as low as 35 degrees C. The free PVX CP tertiary structure was also disrupted by very low sodium dodecylsulfate and cetyltrimetylammonium bromide concentrations: 3 to 5 moleculs of the surfactants per the CP molecule were sufficient to induce its total disruption. At the same time, these treatments did not result in any changes in the PVX CP secondary structure. Incorporation of the CP subunits into the PVX virions resulted in a strong increase in their stability to effects of increased temperatures and surfactants. This combination of highly labile tertiary structure and rather stable secondary structure of free PVX CP subunits may represent a structural basis for recently observed capacity of the PVX CP moleculs to assume two different functional states in the virion.

[Experimental comparative evaluation of the functional capacities of ectopically grown fetal organs].

The interest for fetal organ, tissue, and cell implantation as therapeutic means in the treatment of some diseases is presently increasing. Hence, the aim of the present investigation was the comparative evaluation of the functional potential of ectopically grown fetal organs of different (ecto-, meso- and endodermic) origins. Unified operative model was the fetal organ fragment implantation into an ear subcutaneous pouch (without restoration of vascular and nervous links of the implant with the recipient organism). The implant isolation in vitro varied from 15 to 50 min. As control, intact animals and animals with streptozotocin diabetes and hepatic lesions due to the main bile duct ligature, were used. The implanted and ectopically grown fetal organs, though of different origins, developed functional activity. The best adult-like function was obtained in intestinal, gastric and cardiac implants, i.e. in organs with a cavity and a well developed self-regulation system. Poorer results were obtained in great digestive glandular implants--pancreas and liver. In the best cases when the implant function was very closed to the adult organ, a difference nevertheless was observed. The model of ectopic implantation of fetal organs may be useful for study of the organ and tissue function ontogenesis (up to the moment of natural ageing involution), for the evaluation of different isolated factor influence on organ and tissue physiology and pathology. Although being optimistic in respect to clinical application of fetal organ and cell implantation, this study does not prevent us from being cautions.

[Thrombectomy as a method of surgical treatment of thrombosis of a mechanical prosthesis of the heart valve (a description of three cases)]. / Trombéktomiia kak metod khirurgicheskogo lecheniia tromboza mekhanicheskogo proteza klapana serdtsa (opisanie trekh sluchaev).

The article presents three clinical observations of successful thrombectomies in patients with thromboses of modern bicuspid prostheses of the heart (MEDINZH-2, Carbo Medics) which was 21.4% of all operations (14) for acute thrombosis of the artificial heart valve. It should be taken into consideration that such kind of operation is possible when there are easily removed small loose thrombus, good fixation of the prosthesis and a complete endothelization of the cuff.

[Early results of surgical treatment of infective endocarditis]. / Neposredstvennye rezul'taty khirurgicheskogo lecheniia infektsionnogo éndokardita.

Operations were performed on 183 patients with infective endocarditis and injury of the valve apparatus of the heart. Duration of the disease was from 5 weeks to 9 years. Insufficiency of circulation of the III-IV functional class was noted in 92% of the patients. High activity of the infective process observed in 30% of the patients by the moment of operation did not influence the results of surgical treatment. Postoperative lethality was 7.6%.

[On the etiology of aortal insufficiency]. / K voprosu ob étiologii aortal'noi nedostatochnosti.

The authors describe the results of valvulometry, traditional histological and cytological investigations of dissected valves of 1084 patients and an analysis of causes of aortal insufficiency as compared to the literature data for the last 80 years. The main causes of heart valve diseases are considered to be mesenchymal dysplasia and infective endocarditis.

Translational activation of encapsidated potato virus X RNA by coat protein phosphorylation.

Previously we showed that encapsidated potato virus X (PVX) RNA is nontranslatable in vitro, but can be converted into a translatable form after binding to PVX particles of PVX-coded movement protein, the product of the first gene of triple gene block (TGBp1). Here we report that a similar effect occurs via in situ phosphorylation of the PVX coat protein (CP) by Ser/Thr protein kinase (PK) C, the mixture of casein kinases I and II or by cytoplasmic PK(s) from Nicotiana glutinosa leaves. Immunochemical analyses indicated that phosphorylation induced conformational changes in PVX CP. The N-terminal region of the PVX CP, rich in Ser and Thr residues, is exposed at the virion surface and can be removed by treatment with trypsin. We showed that (i) trypsin treatment removed the bulk of (32)P-radioactivity from in situ phosphorylated PVX CP, (ii) PVX containing N-terminally truncated CP (PVX-Ptd) failed to be translationally activated by phosphorylation, and (iii) the specific infectivity of PVX-Ptd was reduced. However, the PVX-Ptd RNA remained intact and PVX-Ptd could be translationally activated by the PVX MP TGBp1. We hypothesize that phosphorylation of the parental PVX by cytoplasmic PK(s) in vivo renders PVX RNA translatable in primary inoculated cells, whereas translational activation of the progeny virions destined for plasmodesmata trafficking is triggered by TGBp1.

[Immediate results of using the radial artery in direct revascularization of the myocardium]. / Neposredstvennye rezul'taty ispol'zovaniia luchevoi arterii dlia priamoi revaskuliarizatsii miokarda.

The authors discuss results of more than 300 operations of the aorto-coronary bypass using the radial artery as a shunt. An analysis of the initial state of the patients, the intraoperative, early postoperative and intrahospital periods was made. Special attention was given to specific features of the isolating and using the radial artery grafts. Specific complications resulting from the application of them were analyzed and recommendations are given for prophylactics of such complications. The experiences with using the radial arteries allow to recommend it in revascularization of the myocardium. It is one of the ways of improving immediate and long-term results of operations on patients with ischemic heart disease.

[A method of isolation and preparation of the radial artery for direct revascularization of the myocardium]. / Metodika vydeleniia i podgotovki luchevoi arterii dlia priamoi revaskuliarizatsii miokarda.

The authors describe a technique of the isolation, preparation and use of the radial artery for the aortocoronary shunting for ischemic heart disease. The method is anatomically valid and approbated in 300 operations on the open heart. Safety and efficiency of using the radial artery is due to its not traumatic isolation, original preparing for shunting and medicamental prevention of its spasm.

[Rare causes of the dysfunction of mechanical bicuspid heart valves]. / Redkie prichiny disfunktsii mekhanicheskikh dvustvorchatykh klapanov serdtsa.

The authors share the observations from their cardiosurgical practice showing that one of the causes of sudden death or of rapid worsening of the state of patients with implanted bicuspid artificial valves might be their dysfunction resulting both from breakage of the hinged mechanisms of the valve with its dislocation and migration and from the disturbed mobility of the valve cusp due to a thrombus formed in the atrium. The observations show that the "ideal" construction of the valve is to be created.

Properties of the coat protein of a new tobacco mosaic virus coat protein ts-mutant.

Amino acid substitutions in a majority of tobacco mosaic virus (TMV) coat protein (CP) ts-mutants have previously been mapped to the same region of the CP molecule tertiary structure, located at a distance of about 70 A from TMV virion axis. In the present work some properties of a new TMV CP ts-mutant ts21-66 (two substitutions I21=>T and D66=>G, both in the 70-A region) were studied. Thermal inactivation characteristics, sedimentation properties, circular dichroism spectra, and modification by a lysine-specific reagent, trinitrobenzensulfonic acid, of ts21-66 CP were compared with those of wild-type (U1) TMV CP. It is concluded that the 70-A region represents the most labile portion of the TMV CP molecule. Partial disordering of this region in the mutant CP at permissive temperatures leads to loss of the capacity to form two-layer aggregates of the cylindrical type, while further disordering induced by mild heating results also in the loss of the ability to form ordered helical aggregates.

[The transplantation to adult animals of the pancreas from fetuses]. / Peresadka vzroslym zhivotnym podzheludochnoi zhelezy plodov.

The possibility of using the syngeneic and allogeneic foetal pancreas implantation was shown for therapy of diabetes mellitus. Cases of the implantation with no immunosuppression were studied in 57 patients.

Complete nucleotide sequence and genome organization of a tobamovirus infecting cruciferae plants.

Genomic RNA sequence of a tobamovirus infecting cruciferae plants (cr-TMV) was determined. The RNA is composed of 6312 nucleotides and contains four ORFs encoding the proteins of 122K (ORF1), 178K (ORF2), 29K (ORF3) and 18K (capsid protein, ORF4). ORF4 overlaps ORF3 by 74 nucleotides and the overlapping region can be folded into a stable hairpin structure. The 3'-terminal region of the cr-TMV RNA preceding the tRNA-like structure was shown to form six potentially stable pseudoknots.

[The transplantation to adult animals of fetal small intestine]. / Peresadka vzroslym zhivotnym tonkoi kishki plodov.

Use of the ectopic growth (culture) of foetal small intestine in vivo as a model for study of normal and pathological development of an organ or its different structures was shown to be possible. Complete structural and functional development of foetal small intestine was reached under certain conditions of its implantation.