Search PubMed⌕ Search

Biomedical subjects

M V Krylov

Publications and source records attributed to M V Krylov.

31 records · Page 2Linked to original sources
PubMedDate not supplied

[Evolutionary complication of life cycles in Coccidea (Sporozoa: Coccidea)].

Similar strategies to preserve a species were evolved independently in different groups of Coccidea. Polyenergid oocysts and tissue cysts are found in representatives of the orders Protococcidiida and Eimeriida. Hypnozoits are found in Karyolysus lacerate and Plasmodium vivax; transovarial transmission of parasites occurs in life cycles of Coccidea of the genera Karyolysis and Babesia. Formation of heteroxenity in groups of Coccidea apparently was developed by different ways and in different periods. In some groups (Cystoisospora, Toxoplasma, Aggregata, Atoxoplasma, Schelackia, Lankesterella, and Calyptospora), recent definitive hosts were initial hosts; in other groups (Sarcocystis, Karyolysus, Haemogregarina, Hepatozoon, Plasmodium, Haemoproteus, Leucytozoon, Babesiosoma, Theileria, and Babesia), intermediate hosts were initial hosts.

Animals↗
PubMedDate not supplied

[Coccidia (eimeriidae) of fishes (Cypriniformes) in the continental waters of Russia].

Thorough data on 67 coccidian species of the genera Eimeria, Goussia, and Isospora parasitizing fishes in the continental waters of Russia are given. Authors, year of description, synonyms, morphofunctional organization, and list of the hosts are reported for each species. The paper is supplied with figures of the exogenic stages of coccidia (oocysts).

Animals↗
PubMedDate not supplied

[Biosynthesis of folic acid in Eimeria tenella (Coccidia)].

The inhibitory analysis has shown that E. tenella does not include ready folic acid into metabolic process but synthesizes its metabolite, 7:8-dihydrofolic acid (DHFA), from its precursor, para-aminobenzoic acid (PABA), which enters the host's organism. PABA can be fully substituted in the process of metabolism by sulphadimesin (SD) at the molar ratio PABA: SD=1: 16.7. As a concurrent antagonist of PABA SD is 6 times stronger in the parasite-host system of Coccidia than in bacteria in cultural medium. The increase in PABA content in relation to SD more than 1: 16.7 intensifies the viability of Coccidia that is expressed in higher lethality of chicks, which reaches its maximum at PABA : SD=1 : 1.25. A further increase in the content of PABA does not affect the host's lethality. The decrease in PABA in relation to SD lower than 1 : 16.7 reduces the viability of Coccidia. Nucleic bases G, A transforming in the organism into corresponding nucleotids and aminoacids, 1-metionin and glycine, which are the products of biosynthesis with a participation of DHFA, do not stimulate the viability of E. tenella that apparently is associated with the non-capability of the host to assimilate timidin.

4-Aminobenzoic Acid↗
PubMedDate not supplied

[Presence of genetic exchange in Crithidia oncopelti (Trypanosomatidae) studied with drug resistance markers].

Strains resistant to 100 mkg/ml of cycloheximide (ChxR100) and to 2.5 mg/ml of chloramphenicol (CapR2.5) were used in studies for the presence of genetic interchange in C. oncopelti. Phenotypes of these strains were stable on the nonselective medium and specific. Strains ChxR100 and CapR2.5 were mixed in equal proportions, cultivated during 7 days and tested. Under consecutive effect of inhibitors the culture of strains mixture and clones isolated from it exhibited double resistance. Phenotypes of recombinant clones were stable on the nonselective medium during, at the minimum, 70 to 90 cell generations. At the same conditions control cultures of parental strains and clones did not exhibit resistance that excludes the possibility of origin of cells resistant to both antibiotics from Crithidia of one of the parental strains as a result of secondary mutation. Thus, the results obtained show convincingly the presence of genetic interchange between flagellates of ChxR100 and CapR2.5 strains.

Animals↗
PubMedDate not supplied

[Multiple forms of malate dehydrogenase (EC 1.1.1.37) in Crithidia asclepii and C. oncopelti (Mastigophora, Trypanosomatidae)].

Isozyme analysis of mMDH in Crithidia asclepii and C. oncopelti by means of electrophoresis and densimetry method suggests the diploidness and genetic exchange in these organisms. Synthesis of mMDH in C. asclepii is checked by duplicated polymorphic loci MDH-1 and MDH-2, each with two alleles. In C. oncopelti two "daughter" loci are functioning too, polymorphic MDH-1 with 3 alleles and monomorphic MDG-2. Resemblance and differences in the isozyme spectra of mMDH can be used for taxonomic purposes.

Alleles↗
PubMedDate not supplied

[Pharmacokinetics and toxic properties of chimcocide].

The data on the pharmacokinetics are provided and toxicological characteristics is described in detail of a new highly effective anticoccidal and antitoxoplasmic drug chimcoccide (1,3-bis-/p-chlorbenzylidenamino/guanidine). Chimcoccide is not toxic when applied in prophylactic and therapeutic doses (6 and 12 mg/kg) for coccidosis and toxoplasmosis of animals. It does not disturb the biosynthesis of DNA, RNA, protein or activity of NADP-specific malate dehydrogenase and isocitrate dehydrogenase in organs and tissues of animals. When given in the doses indicated the drug inhibits mitochondrial monoamine oxidase of the brain and liver of rats and chickens.

Animals↗
PubMedDate not supplied

[The specificity of blastocysts (Rhizopoda: Lobosea)].

The analysis of specificity of blastocysts was based on the data on host association and on experimental data. In experiments we failed to infect the geese (Anser anser) with Blastocystis galli taken from the fowl (Gallus gallus) and also failed to infect the fowl with B. suis taken from the pigs (Sus scrofa domestica). Experimental data and field observations of blastocysts distribution among different groups of hosts point out that the same species of blastocysts can not parasitize in hosts belonging to different classes and orders. The examination of 89 fish specimens belonging to 14 species of Osteichthyes taken from the Neman delta did not discover any blastocysts.

Animals↗
PubMedDate not supplied

[Nucleic acid and protein synthesis in the body of chicks infested by various species of Eimeria].

The infection of chicks with optimal immunogenic doses of oocysts of E. tenella and E. acervulina results in the activation of biosynthesis of proteins and nucleic acids in the Fabricius bursa, spleen, thymus and blind processes of the intestine. The infection causes the increase in the quantity and synthesis intensity of immunoglobulins G and M that suggests a stimulation of cellular and immunity factors in the ogranism of an immunized bird. Maximum changes in biosynthesis of compounds studied are reported four days after the infection that confirms high immunogenic properties of the second generation schizonts. A study of protein synthesis in limphoid organs of chicks infected only with E. tenella has yielded the same results. The infection with E. acervulina caused but negligible changes in the protein metabolism, i.e. coccidians of E. tenella possess more immunogenic properties.

Animals↗
PubMedDate not supplied

[Blastocystis from primates].

A new species, Blastocystis lemuri sp. n., was found in the Lemur catta. Size of blastocysts in a culture is 10.25-35.25 mkm, the number of nuclei varies from 1 to 2. The optimum temperature for cultivation is +39 degrees.

Animals↗
PubMedDate not supplied

[The distribution of Blastocystis according to different systematic groups of hosts].

After the carried out examination of different animals belonging to four phyla, Annelida, Mollusca, Arthropoda, and Chordata, the blastocysts were detected within three phyla, Annelida, Arthropoda, and Chordata. Within the phylum Annelida the blastocysts were found in Hirudinea, within the phylum Arthropoda--in Insecta, within the phylum Chordata--in Amphibia, Reptilia, Aves, and Mammalia.

Amphibians↗