Structure and biological features of the temperate phage of Bacillus thuringiensis var. galleriae 69/9, sensitive to chloroform

A new temperate bacteriophage designated Px1 has been isolated from the culture of Bacillus thuringiensis var. galleriae 69/6 producing enthobacterin. The bacteriophage belongs to morphological group B1 in accordance with the classification by D. Reanney and H. Ackerman. The bacteriophage head has an isometric multifaceted form with 40 nm diameter. The length of its noncontractile transversely lined tail is 130 nm. High sensitivity to chloroform is peculiar of the phage. The lytical specter of the phage Px1 has been studied. The phage is shown to be capable of efficient transduction of plasmids between the bacteria of Bacillus cereus group.     

Variability of Bacillus thuringiensis bacteriophages with C2-morphology

Biological as well as physicochemical properties of Bacillus thuringiensis bacteriophages "17" and "7/13" having C2-morphology and isolated from factory phagolysates were studied. The bacteriophages are identical in the lytic spectrum++, morphology, size, GC-content, have the same buoyant density. The physical map for restriction endonucleases EcoRI, HindIII, SalGI and MvaI has been constructed of the bacteriophages DNA. Heteroduplex analysis has revealed the nonhomologous region of the deletion-insertion type as a 0.8 Md loop. The bacteriophages "17" and "7/13" are concluded to be closely related but not identical.     

Cytogenetic effects of cyclophosphamide on human lymphocytes in vivo and in vitro

A comparative study of cytogenetic effects in human lymphocytes caused in vivo by cyclophosphamide (CP) after intravenous injection and in vitro by exposure of plasma of the same patients was carried out. It was found that the frequency of induced chromosome aberrations (CA) and sister-chromatid exchanges (SCE) increased linearly for SCE and exponentially for CA within the 'dose' of alkylating activity of CP metabolites. Parameters of 'cytogenetic effect-dose' in vivo and in vitro coincided. The intensity of cytogenetic effects varied between individuals.     

Inhibition of the SHV-1 beta-lactamase by sulfones: crystallographic observation of two reaction intermediates with tazobactam

Two species resulting from the reaction of the SHV-1 class A beta-lactamase with the sulfone inhibitor tazobactam have been trapped at 100 K and mapped by X-ray crystallography at 2.0 A resolution. An acyclic form of tazobactam is covalently bonded to the catalytic Ser70 side chain, and a second species, a five-atom vinyl carboxylic acid fragment of tazobactam, is bonded to Ser130. It is proposed that the electron density map of the crystal is a composite picture of two complexes, each with only a single bound species. It is estimated that the two complexes exist in the crystal in approximately equal populations. Results are discussed in relation to the mechanism-based inhibition of class A beta-lactamases by the similar inhibitors sulbactam and clavulanic acid.     

Clinical radiological analysis of 99mTc-technetryl myocardial scintigraphy

Resting and exercise 99mTc-technetryl myocardial scintigraphies were performed in 145 patients with various cardiovascular diseases. Normal lowered and elevated radioopaque accumulations were found to be present in both coronarogenic and noncoronarogenic diseases. Four degrees of agent hypofixation and four types of stress myocardial scintigraphies were interpreted from clinical points of view. Coronary failure is characterized by more severe hemoperfusion disorders (degrees 3-4) and the 3rd-4th variant of stress myocardial scintigraphy.     

Experience with vaccine prophylaxis of hepatitis B among different groups of children

The immunological activity of different vaccines against hepatitis B was evaluated in the Hepatological Center organized on the basis of the Infectious Hospital in Tula. Newborn infants were immunized with the use of the following vaccines: Engerix B (Belgium), Combiotech (Russia), Euvax B (Aventis Pastèur, South Korea). Altogether, after the full course of immunization anti-HBs were detected in 76 children out of 81 (in 93.8%). Vaccine Engerix B, when introduced according to the schedule 0-1-2-12 months, exhibited high immunogenic properties in a group of infants born of women with persistent HBs-antigenemia. Anti-HBs at a concentration exceeding 1000 I.U./I could be detected in 84.6%. In another group of children immunized according to the schedule 0-1-6 months first with vaccine Combiotech at the age of 0 and 1 month, then (at the age of 6 months) with vaccine Euvax, the presence of postvaccinal anti HBs at protective concentration was registered in all children. After immunization against hepatitis B with the use of all above-mentioned vaccines introduced according to both schedules high immunological activity and safety of immunization were noted.