Biological Efficiency of the Prepupae <Emphasis Type="Italic">Hermetia illucens</Emphasis> in the Diet of the Young Mozambique Tilapia <Emphasis Type="Italic">Oreochromis mossambicus</Emphasis>

It has been noted that the introduction of small doses of dry prepupae of Hermetia illucens flies into the diet of the young Mozambique tilapia Oreochromis mossambicus (0.5 g/kg feed) had a positive effect on the growth and development of fish. It was found that the average daily gain in the experimental group was 0.7 g. It was established that the blood biochemical parameters were within the norm in the fish of all groups; however, in the experimental tilapia, the erythrocyte sedimentation rate was significantly lower and a tendency to increase in the amount of hemoglobin and glucose was noted. It was revealed that in the seminiferous tubules of fish in the experimental group, the number of mature sperm was 5.9 times higher compared with the control, indicating an increase in the rate of spermatogenesis. It is assumed that the observed effects are due to the high content of manganese in the prepupae present in a biologically active divalent form.     

Trofosides A and B and other cytostatic steroid-derived compounds from the Far East starfish Trofodiscus über

Three new polar steroids identified as trofoside A, (20R,24S)-24-O-(3-O-methyl-beta-D-xylopyranosyl)-3beta,6alpha,8,15beta,24-pentahydroxy-5alpha-cholestane, its 22(23)-dehydro derivative (trofoside B), and 15-sulfoxy-(20R,24S)-5alpha-cholestane-3beta,6beta,8,15alpha,24-pentaol sodium salt, were isolated from Trofodiscus uber starfish extracts collected in the Sea of Okhotsk. Two known compounds, trofoside A aglycone, (20R,24S)-3beta,6alpha,8,15beta,24-pentahydroxy-5alpha-cholestane, and triseramide, (20R,24R,25S,22E)-24-methyl-3beta,6alpha,8,15beta-tetrahydroxy-5alpha-cholest-22-en-27-oic acid (2-sulfoethyl)amide sodium salt, were also found. The structures of the isolated polyoxysteroids were established from their spectra. Minimal concentrations causing degradation of unfertilized egg-cells of the sea-urchin Strongylocentrotus intermedius (C(min)) and terminating the cell division at the stage of the first division (C(min) embr.), as well as the concentrations causing 50% immobilization of sperm cells (ImC50) and inhibiting their ability to fertilize egg-cells by 50% (IC50) were determined for the isolated compounds. Of three compounds highly toxic in embryos and sea-urchin sperm cells, the polyol with a sulfo group in the steroid core was the most active; two glycosides with monosaccharide chains located at C3 and C24 atoms were less toxic. Note that all the compounds with the spermiotoxic activities differently affected the embryo development. The positions of monosaccharide residues in the core considerably influence the compound activity. For example, both mono- and double chained glycosides with the monosaccharide fragment at C3 and C24 atoms are active against sea-urchin sperm cells and embryos, whereas the C24 glycosylated trofoside A does not affect embryos and displays a poor spermiotoxicity.     

The quality standardization of a national vaccine against yellow fever

One of the commercial lots of yellow fever vaccine has been attested as the National Branch Standard (NBS) of yellow fever vaccine. This NBS has been studied in all tests required by the regulations for standard vaccines. The NBS has been found to meet the necessary requirements in all its characteristics. The study of the thermostability of the NBS at temperatures of 4-10 degrees C, 20-22 degrees C, 37 degrees C during storage for 24 hours to 1 year has revealed the rapid loss of the infectious capacity of the virus at the above temperatures and its high stability during storage at -20 degrees C. Thus, the NBS has been found to retain the required level of immunizing potency for 3 months at a temperature of 4-10 degrees C, for 1 month at 20-22 degrees C and for 2 weeks (the term of observation) at 37 degrees C. The heat resistance of the NBS of yellow fever vaccine corresponds to the WHO requirements. The newly developed NBS has been used as the standard preparation for controlling 27 lots of commercial yellow fever vaccine.     

DNA-polymerase alpha from human placenta. Effectiveness of interaction between oligothymidylates of different lengths and the template-binding site

Modification of human placenta DNA polymerase alpha by (pT)2pC[Pt2 + (NH3)2OH].(pT)7 was investigated. The linear time dependence of the enzyme activity logarithm suggested a pseudo-first order for modification. Kd value of enzyme-affinity reagent complex (0.5 microM) was estimated. The enzyme inactivation by the affinity reagent and protection from inactivation in the presence of oligonucleotides of varying length were used for determining Kd values of the enzyme-ligand complexes. Oligonucleotide d(pT)2pC(pT)7 (Kd 0.15 microM), d(Tp)9T (Kd 0.15 microM) and [d(Tp)9]ddT (Kd 0.15 microM) protected the enzyme from inactivation with equal efficiency. The protective action of oligothymidylates d(Tp)nT (where n changes from 3 to 14) strongly depended on the chain length, the Kd values diminishing from 5.3 to 0.0091 microM in the geometrical progression. The addition of one link to the oligothymidylate chain resulted in 1.71-fold increase in the oligonucleotide affinity for the enzyme specific site. Such a change corresponds to Gibbs energy change of about 0.32 kcal/mole. It is supposed that the monomer units of pentadecathymidylate (at least beginning with the third one) in d(Tp)14T-enzyme complex form neither hydrogen bonds nor electrostatic linkages with the enzyme. Kd values of oligonucleotides as templates are shown to reflect quite well the true affinity of template for the enzyme. This affinity increases in the presence of a primer. However, the ratio of the affinity for different oligonucleotides does not change in the presence or absence of a complementary primer.     

Local hemodynamics of the brain of the white rat at late periods after discontinuation of neurosis-inducing treatment

In the visual and sensomotor cortical areas of neurotized rats, velocity of local cerebral blood flow (vLCBF) was measured by the method of hydrogen clearance in 4-6 weeks after the termination of neurotization. No significant decrease of vLCBF which had been observed at the late stages of neurotization, was found in the animals under study. However noticeable vLCBF oscillations indicated vegetovascular dystonia. Disturbances in vLCBF controlling system are supposed to be one of remote sequelae of neurotization.     

Transcellular ionic currents studied by intracellular potential recordings in Neurospora crassa hyphae. Transfer of energy from proximal to apical cells

Membrane potentials, input resistances, and electric coupling in the apical parts of N. crassa growing hyphae were recorded with the aid of intracellular microelectrodes. It was revealed that the apical cells were always depolarized by 10 to 30 mV as compared to the adjacent proximal cells. The septal pore maintained an electrical resistance of 4 to 6 M omega. The calculated values of the endogenous electrical current passing through the septal pore varied between 0.5 and 1 nA. Electrical isolation of the apical cells resulted in their depolarization from 120-150 mV to 40-60 mV, characteristics of the membrane potential value of N. crassa adult hyphae with completely blocked electrogenic pumps. A simultaneous increase in the input resistance value from 15-20 M omega to 40-80 M omega was observed. The above data can be explained assuming that H+-ATPase activity was greatly lowered in the apical cells. Thus in the intact hyphae with electrically coupled cells energy is transferred from the proximal hyphal compartments to the apical ones.     

Synthesis of oligoribonucleotides via ribonucleoside-H-phosphonates

The synthesis of oligoribonucleotides via 5'-O-dimethoxytrityl-2'-E-tetrahydropyranyl-N-acylribonucleoside 3'-H-phosphonates is described. With these synthones and pivaloyl chloride as condensing agent, the synthesis of CpC and GpA in solution and the polymer support synthesis of (Up)4U and (Up)5C in manual variant and at the automatic synthesizer "Victoria-4M" was performed. The obtained oligonucleotide-H-phosphonates were oxidized to phosphates both with usually employed aqueous iodine solution and with of CCl4-Et3N-H2O (the Todd-Atherton reaction).     

Effective complementarily-addressed photomodification of nucleic acids by oligonucleotide derivatives, containing aromatic azido groups]

Highly effective site-specific photomodification of a DNA-target was carried out with oligonucleotide reagents carrying aromatic azido groups. Oligonucleotide derivatives with a photoactive function R on the 5'-terminal phosphate and at C-5 atom of deoxyuridine were synthesized: R1NH(CH2)3NHpd(TCCACTT) and d(ULNHRCCACTT), where R1 is p-azidotetrafluorobenzoyl, R2 is 2-nitro, 5-azidobenzoyl, R3 is p-azidobenzoyl; LNH = -CH2NH-, -CH2OCH2CH2NH- or -CH2NHCOCH2CH2NH-. The prepared compounds form stable complementary complexes and effect site-specific photomodification of the target DNA. The modification of pentadecanucleotide d(TAAGTGGAGTTTGGC) with the reagents was investigated. Maximum extent of modification strongly depended on the reagent's type, the photoreagent with R1 being the most effective. Whatever the binding site was, this agent provided a 65-70% modification in all cases except LNH = -CH2NH-, when the yield was twice lower. For the reagents bearing R1 the modification sites were identified. Selective modification at the G9 residue was detected in the case of LNH = -CH2OCH2CH2NH- and when a photoactive group was linked to the terminal phosphate.