Genetic structure of crucian carp (Cypriniformes, Cyprinidae, Carassius L. 1758) populations of middle-Dnieper basin

Comparative analysis of Middle Dnieper crucian carp's population structure was made by means of biochemical gene marking, cytometry and biological analysis. As a result the structure was found, which may by expounded like association of the genetically related species and forms. This association consists of diploid C. auratus (which predominates in population), C. carassius (which was found in the some of north-eastern reservoirs only) and triploid C. gibelio. In Ukraine the homogeneous populations of C. gibelio can be found on the north-east of Eastern Ukraine only. Though some of individuals maybe present with diploid C. auratus. Besides were found hybrid form: diploid C. auratus-C. carassius and presumably tetraploid C. auratus-C. gibelio and C. gibelio-C. carassius. However in the tetraploid's spectra were absent a number of specific alleles, that marking C. species-one of the parental species of triploid C. gibelio. Therefore presumptive tetraploids have not difference from C. auratus and diploid C. auratus-C. carassius on the gene markers level. Nevertheless they are neatly diagnose by the erythrocytes which have good difference and are bigger then diploid species erythrocytes in 40% (C. auratus-C. gibelio) and 100% (C. gibelio-C. carassius).     

The Genetic Structure of European Goldfish Carassius auratus s. lato (Cyprinidae) in Ukrainian Water Bodies: An Analysis of Bisexual Samples

Biochemical gene mapping of goldfish populations in the middle Dnieper basin demonstrated that 8 out of 17 studied enzyme and protein systems are encoded by duplicated loci and two of them represent isoloci. Noteworthily, the heterozygosity in the studied goldfish samples was significantly higher than the average for bony fish (H _exp = 0.128, 0.135). Cytometric analysis of the samples demonstrated that one of them includes about 20% of presumably triploid females that, nevertheless, did not demonstrate a common electrophoretic pattern of the polymorphic loci, which is typical for unisexual parthenogenetic forms. Moreover, no additional gene duplications (constant heterozygotes), unique alleles (diagnostic patterns), or stable manifestation of a gene dosage effect were revealed in the polyploid females. Several hypotheses were proposed to explain such unusual structure of triploid parthenogenetic individuals.     

Variation of loci encoding homologous enzymes in an evolutionary series of vertebrates

A study of variability of 11 allozyme loci (sAat, G3pdh, Gpi, sIdh, Ldh-A, Ldh-B, sMdh, sMe, sSod, Pgdh, and Sdh) in the evolutionary series of vertebrates from Cyclostomat to Mammalia revealed that (1) in vertebrates, these loci encoding multimeric enzymes are characterized by different heterozygosity levels, the extremes of which (represented by loci Ldh-A and Pgdh) differ from each other more than by a factor of 4; (2) classes of vertebrates markedly differed from one another in genetic variation; lower Tetrapoda are characterized by the highest level of genetic polymorphism, the classes representing the margins of the phyletic line-primitive (Cyclostomata and Chondrchthyes) and advanced (Aves and Mammalia)--have minimum heterozygosity levels, whereas Osteichthyes are characterized by intermediate heterozygosity level; (3) in the evolutionary series of vertebrates, heterozygosity varies rather independently in the groups of loci characterized by low, medium, and high variability. These patterns are explained in the context of intraorganismic factors: integration of mono- and polygenic traits (primarily, body size and ontogeny rate) and evolutionary specialization.     

Population as a Test System

Comparison of the concept that the population is a wave of life with the results of specific studies opens the possibility for the estimation of destructive human activities and their plausible consequences. Specifically, it was noted that radioactive contamination of territories as a result of the accident at the Chernobyl Nuclear Power Station could create prerequisites for the mass reproduction of pests and the expression of diseases dangerous for man and domestic animals.     

Characters of amino acid substitution in LDH-A and LDH-B in the evolutionary line of vertebrates

Structure of lactate dehydrogenase LDH-A (muscle) and LDH-B (heart) subunits is compared in the evolutionary line of vertebrates from Chondrosteous fishes to Mammals. It is revealed persistent differences between them in the amino acid set determining the physical and chemical characteristics of macromolecules. The polypeptide chain of LDH-A is shorter then that of LDH-B but it contains amino acids with higher molecular weight. In LDH-A polarized amino acids are less in number but charged amino acids are more numerous, positive charged amino acids prevail over negative charged ones. The features of polypeptide structure are discussed in connection with differences in the level of intraspecific variability of allozymes in the evolutionary line of vertebrates.     

Genetic structure of unisex hybrid population of frogs Rana esculenta complex in lowland Transcarpathian region

The biochemical genetic marking and analysis of the ploidy and sexual structure of the green frog populations from the Transcarpathian lowlands have demonstrated that this region is inhabited by the unisexual populations composed of the allodiploid females only. Their genome includes a small portion of the marsh frog genic diversity. This phenomenon is discussed in relation to the unisexual population reproduction problem. The assumption is proposed that in the Transcarpathian hybrid populations the hybrids are spawned by the parthenogenesis.     

Genetic diversity, origin, and geographic distribution tendencies of biotypes of polyploid spined loaches (Cypriniformes, Cobitidae, Cobitis) in Ukraine

Sixteen of 28 possible biotypes of C. elongatoides-taenia s.lato (C. taenia, C. tanaitica, C. species-1) have been found in Ukrainian waters. Presumably, the biotypes of C. aff. melanoleuca-tanaitica has also been identified. The share of polyploids among Cobitis on average was 65%, where males made up less than 1% with the same ratio among tri- and tetra-polyploids. The absence of amphydiploidy and presence of individuals with recombinant genotype and abnormal electrophoretic specters, whose frequency sometimes is considerable, are attracting increasing interest. There are two centers of polyploid biotypes creation: southern (the Lower Danube) and northern (the Upper Danube, Oder, and Rhine). The C. taenia and C. species-1 type, which is typical for the northwestern basins of Ukraine, participates in the formation of polyploids in the Rhine alongside with C. elongatoides and C. tanaitica. It is determined that biotypes (C. 2(3) elongatoidestanaitica, C. elongatoides-2(3) tanaitica) in comparison with biotypes whose genome includes the chromosome set of C. taenia are limited in distribution towards the East. This is due to the hybridization of females from these biotypes with males of C. taenia afflicted by genetic instability and reduced viability of posterity.     

The ploidy and genetic structure of hybrid populations of water frogs Pelophylax esculentus complex (Amphibia, Ranidae) of Ukraine fauna

The complex study, including allozyme variability and cytometry of hybrid populations of green frogs Pelophylax esculentus (L., 1758) complex has confirmed that the only region of Ukraine where allodiploid are encountered frequently is the Severski Donets basin (9% of all hybrids). In other areas, only two polyploidy hybrids (0.9%) and one probably autopolyploid individual of each parental species have been registered. According to allozyme specters, all three polyploidy hybrids from the Severski Donets basin were males and belonged to biotype P. esculentus (=lessonae) — 2 ridibundus, and their population in this region has halved during the past decade.     

Genetic variation of Azov and Black sea herring Alosa pontica (Eihwald, 1838), (Clupeiformes, Alosinae) in Danube river: analysis of biochemical gene markers

Genetic variation and structure of Danube stock of Aloca pontica pontica were investigated during the spawning moving by means of biochemical genetic marking. The level of heterozygosity was Hobs = 0,009. It is essentially lower than the average level for populations of other Teleostei and Clupeidae representatives. Polymorphism was defined only for Es-D of 20 analyzed loci expressed in muscle tissues. The allele frequencies for this locus were reliably different in the early spawning and later spawning parts of the stock, as well as proportion of heterozygotes and genotype diversity which was higher at the beginning of spawning moving. These results are discussed from two points of view: genetic differences between subpopulations in the course of spawning moving and presence of two close species of herring which come for the spawning together and hybridize to each other.     

An unusual presentation of a malignant jejunal tumor and a different management strategy

BACKGROUND: Malignant small bowel tumors are very rare and leiomyosarcoma accounts for less than 15% of the cases. Management of these tumors is challenging in view of nonspecific symptoms, unusual presentation and high incidence of metastasis. In this case report, an unusual presentation of jejunal sarcoma and management of liver metastasis with radiofrequency ablation (RFA) is discussed. CASE PRESENTATION: A 45-year-old male presented with anemia and features of small bowel obstruction. Operative findings revealed a mass lesion in jejunum with intussusception of proximal loop. Resection of bowel mass was performed. Histopathological findings were suggestive of leiomyosarcoma. After 3-years of follow-up, the patient developed recurrence in infracolic omentum and a liver metastasis. The omental mass was resected and liver lesion was managed with radiofrequency ablation. CONCLUSION: Jejunal leiomyosarcoma is a rare variety of malignant small bowel tumor and a clinical presentation with intussusception is unusual. We suggest that an aggressive management approach using a combination of surgery and a newer technique like RFA can be attempted in patients with limited metastatic spread to liver to prolong the long-term survival in a subset of patients.