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Aim: To improve the outcomes in patients with chronic ruptures of the Achilles tendon followed by advanced diastase and reduced function of the gastrocnemius muscle by using of new surgical method., Material and Methods: The authors proposed a new method of Achilles tendon repair for diastase over 10 cm. It imposes transposition of the tendons of short fibular muscle and posterior tibial muscle. Schemes and stages of surgery are presented in figures. The authors described clinical example of patient with chronic rupture of the Achilles tendon, illustrations of surgical stages and the outcome., Results: New surgical approach was applied in 16 patients. The control group consisted of 21 patients who underwent repair by Chernavsky, Krasnov. Clinical and biomechanical methods were used for evaluation. Functional myography and podography to assess the asymmetry of gait were performed. Our data confirmed the advantage of new approach.

Reverse transcriptase (RT) preparations containing various molecular forms of the enzyme consisting of alpha- and/or beta-subunits have been isolated from E. coli cells transformed with plasmid pMF14 containing the Rous sarcoma virus (RSV) pol gene. The three possible dimeric forms of the enzyme demonstrated DNA polymerase activity, the relative activities of the alphaalpha, betabeta, and alphabeta forms being about 1:3:4. RNase H activity is associated with the betabeta and alphabeta dimers but not with the alphaalpha dimer. Comparison of the enzymic properties of the various dimers and dissociation--reassociation results suggest that the betabeta and alphabeta dimers of the RSV recombinant reverse transcriptase are similar to the corresponding virion RT forms.

The effect of weak direct and alternative magnetic fields adjusted to cyclotron frequencies of ions of polar amino acids leads to a functional inactivation of the recombinant reverse transcriptase of Rous sarcoma virus, which is coupled with the proteolysis of this enzyme.

Preparations of Rous sarcoma virus reverse transcriptase isolated from a culture of E. coli HB101 (pMF14) and purified to homogeneity were used to study the steady state kinetics of DNA polymerization and inhibition of DNA-polymerase activity. DNA synthesis was examined using a system of poly(rA) as template, oligo(dT) as primer and dTTP as nucleotide substrate. Kinetic constants for steady state conditions were determined. The substrate initial velocity patterns point to an ordered mechanism which results in the formation of a ternary complex, in which the template-primer is the first to bind to the enzyme. Inhibition of the DNA-polymerase activity of the enzyme by various inhibitors was studied. Analysis of final products of the DNA-polymerase reaction revealed the presence of distribution syntheses of the DNA chain by the alpha alpha-subunit form of the enzyme.

On the basis of treatment and examination of 2675 patients with residual effects of poliomyelitis and consequences of the nervous system traumata are considered the functioning peculiarities of vascular system of the lower extremities in case of absence or abrupt decrease of pumping function of the skeletal muscles. There have been detected discrepancies between the reovasographic regional blood circulation pattern and the microcirculation state indexes in the tissues of the damaged extremity. They have studied the dynamics of the hemodynamics indexes in the process of preoperative preparation, during early and late postoperative periods as well as during remote postoperative periods. There is suggested the idea of correlation of the regional hemodynamics with the extremity supporting state.

Enzyme preparations of Rous sarcoma virus (RSV) reverse transcriptase have been isolated from a culture of E. coli HB101(pMF14). The enzyme has been purified to homogeneity and been shown to consist of two subunits, of molecular mass 97.4 and 61.3 kDa, respectively. The optimum conditions for the DNA polymerase and RNAase H activities, fidelity of DNA synthesis on a homogeneous RNA template, and the inhibitory effect of azidothymidine triphosphate have been determined. Data on the use of RSV recombinant reverse transcriptase for cDNA synthesis are given.

Preparations of recombinant reverse transcriptase RSV were isolated from E. coli HB101/pMF14 cell cultures. The enzyme purified to homogeneity was shown to be made up of two subunits with molecular masses of 97 +/- 4 and 61 +/- 3 kDa. A comparison of enzymatic properties of recombinant transcriptase to those of the enzyme isolated from the RSV (Rauss sarcoma) virus demonstrated that in the preparations under study the recombinant reverse transcriptase exists in a subunit form, alpha beta, and may acquire a relatively stable configuration, alpha 2.

Six mutants of phage T5 have been selected by temperature inactivation in the presence of chelate-forming agents. Hybridization of DNA of the mutants with 4S RNA of phage T5+ has shown that all mutants have the deletions affecting tRNA genes. The size of the deletions and their location about the sites of DNA clevage with endonucleases EcoR1, Hind III, PstI and the nicks have been determined.

The relationship between the electrophoretic mobility of double stranded DNA fragments electrophoresed in agarose gel and their molecular weights within the range from 1.10(6) to 8.10(7) daltons and agarose concentration 0.3--2.0% has been studied. Partial hydrolysis products of lambda phage DNA obtained by restriction endonuclease EcoRI have been separated. Partial hydrolysis products have been identified by determining the fragments of full cleavage as well as by genetic methods using a system of transformation of E. coli cells treated with CaCl2, which have been infected with different helper-phages containing definite gene mutations.

Plasmidphage lambda NM::pBR322 has been constructed in vitro and characterized. Under normal conditions the hybrid DNA molecule undergoes a lytic cycle of phage development, whereas in the presence of antibiotic lambda DNA replicates in the cell extrachromosomally as a plasmid. Properties of plasmidphage lambda NM::pBR322 have been compared with the earlier constructed lambda gt::pMB9. It has been demonstrated that plasmid pMB9 in vivo can be precisely excised from the lambda gt::pMB9.

The DNA of Bacteriophage T5+ has been treated with restriction endonucleases EcoRI, HindIII, BamI, SmaI, PstI, SalI, KpnI and the electrophorectic pattern obtained in agarose gel has been analyzed in order to localize the specific cleavage sites on the T5 DNA. The localization of cleavage sites has been resolved from the electrophoretic pattern of double and partial digests, the digests of isolated restriction fragments and the digests of deletion mutant T5 st(O) DNA. Four BamI cleavage sites have been found and localized on the physical map of T5 DNA at 0.225; 0.68; 0.715 and 0.725 fractional lenght. Endonuclease PstI cuts T5 DNA at 11 sites: 0.095; 0.215; 0.320; 0.510; 0.635; 0.675; 0.710; 0.770; 0.810; 0.840; 0.875 fractional length. Six KpnI cleavage sites have been mapped at 0.140; 0.160; 0.530; 0.720; 0.760; 0.840 fractional length. 14 out of 17 HindIII cleavage sites have been localized at 0.10; 0.24; 0.255; 0.345; 0.40; 0.52; 0.54; 0.57; 0.70; 0.76; 0.80; 0.84; 0.87; 0.89, fractional length of T5 DNA. Complete cleavage map of the phage genome is presented for seven restriction enzymes.

Bacteriophage T5 is not confined by the restriction systems of the second type EcoRII and EcoRV. Bacteriophage T5 DNA is not modified by EcoRII and EcoRV methylases in vivo. The sites of recognition for restriction endonuclease EcoRV are mapped at 24.4; 57.6; 68.5; 70.2% of T5 DNA, while the sites at 5.1; 7.6% are recognized by EcoRII, the sites at 5.75; 6.0 and 6.5% are recognized by HpaI in FST. A high activity of restriction endonucleases EcoRI and EcoRV is demonstrated in crude extracts of E. coli B834 (RI) and E. coli B834 (RV) cells infected by bacteriophage T5. The simultaneous infection of E. coli B834 (RI) or E. coli B834 (RV) cells by the amber mutants of bacteriophage T5 and the suppressing phage lambda NM761 does not result in the protection of lambda DNA by the T5 anti-restriction mechanism. The presented data support the hypothesis that the anti-restriction mechanism of bacteriophage T5 is based on prevention of T5 DNA contacts with restriction enzymes by a specific phage protein.

The authors analyse their many-year experience gained in the treatment of patients with foot deformities of various origins, carried out at the traumatology clinic of the Kuibyshev D. I. Ulyanov Medical Institute. New surgical techniques for the treatment of congenital talipes, valgus deformity of the first thumb combined with transverse platypodia, paralytic loose, paralytic pes planus and calcaneus are described. The causes of valgus deformities in the patients with infantile cerebral paralysis after achillotomy are discussed on the basis of EMG data. The described methods are superior to the routine ones.