Helminthiases among the population of northwestern Siberia. 1. Opisthorchiasis and mixed invasion in the native inhabitants of the Ob River basin and their clinical course

The use of multifactor statistic analysis for screening population of the northern part of the Ob river basin for helminthiasis allowed the authors to reveal a significant feedback between manifested opisthorchiasis and other types of this disease course in both sexes. The main component analysis indicates that the tentatively control group of males is presented by adolescents (14-17 years old) who are likely to be infected with Opisthorchis without evidence of its clinical manifestations. The correlation analysis demonstrated also a direct relationship between the age and manifest opisthorchiasis, as well as double mixed invasion of males (r-0.15 and 0.26, p less than 0.05 and 0.01, respectively). The first three main components explain about 55% variance in the correlation matrix of initial parameters and allow to reveal the variance source, taking into account, along with differentiation of 4 groups of opisthorchiasis patients, also the age- and sex-dependent combination of opisthorchiasis with other helminthic invasions.     

Screening for antimitotic compounds using the cdc25 tyrosine phosphatase, an activator of the mitosis-inducing p34cdc2/cyclin Bcdc13 protein kinase.

A universal intracellular factor, the "M phase-promoting factor" (MPF), triggers the G2/M transition of the cell cycle in all organisms. In late G2, it is present as an inactive complex of tyrosine-phosphorylated p34cdc2 and unphosphorylated cyclin Bcdc13. In M phase, its activation as an active MPF displaying histone H1 kinase activity originates from the specific tyrosine dephosphorylation of the p34cdc2 subunit by the tyrosine phosphatase p80cdc25. We describe here a colorimetric assay of recombinant human cdc25A tyrosine phosphatase used as a cell cycle-specific target to screen for antimitotic compounds. The glutathione-S-transferase/cdc25A tyrosine phosphatase fusion protein is produced in large amounts of Escherichia coli and easily purified by affinity chromatography on glutathione-agarose. Optimal purification, storage and assay conditions (concentrations of enzyme, p-nitrophenylphosphate and dithiothreitol; duration of assay) have been determined. Using this system we tested 15 compounds currently used in cancer treatment; none of them displayed any inhibitory activity. However, the assay detected the inhibitory activity of vanadate, a reported tyrosine phosphatase inhibitor. The simplicity, speed and possible extensive automation of this assay using an essential cell cycle-regulating component provide a highly specific mechanism-based screen for antimitotic drugs discovery.     

Trematode reproduction in the molluscan host: an ultrastructural study of the germinal mass in the rediae of Himasthla elongata (Mehlis, 1831) (Digenea: Echinostomatidae)

The germinal mass in Himasthla elongata rediae was studied in detail using transmission electron microscopy. It was shown to be a specialized reproductive organ consisting of germinal cells at various maturation stages, supporting cells and stem cells. The germinal mass also contains early cercarial embryos emerging as a result of cleavage division of mature germinal cells. The stem cells that give rise to germinal cells have heterochromatin-rich nuclei with distinct nucleoli and scarce cytoplasm containing mainly free ribosomes and few mitochondria. The differentiating germinal cells undergo a growth, which is accompanied by an emergence of annulate lamellae and the nuage in their cytoplasm, a noticeable development of RER and Golgi apparatus and an increase in the number of mitochondria. The mitochondria form a large group at one of the cell poles. During differentiation, the nucleus and nucleolus of the germinal cell enlarge while the chromatin becomes gradually less condensed. The supporting tissue of the germinal mass is made up of cells connected by septate junctions. These supporting cells are distinctly different in cellular shape and nuclear ultrastructure. Their outgrowths form a tight meshwork housing stem cells, germinal cells and early cercarial embryos. The cytoplasm of the supporting cells in the mesh area is separated into fine parallel layers by labyrinthine narrow cavities communicating with the intercellular space. The supporting tissue contains differentiating and degenerating cells which indicates its renewal. The results of this ultrastructural study lend support to the hypothesis that the germinal cells of digeneans are germ line cells.     

Comparative analysis of carotid-subclavian transposition and stenting in case of stenotic damage of subclavian artery

So carotid-subclavian transposition and stenting are effective and safe methods of correction of occlusive subclavian artery disease. Angioplasty and stenting of the subclavian artery is particularly indicated in patients with high surgical risk. Patients at low risk of surgery is preferred execution carotid-subclavian transposition.     

Multifaceted analysis of the interactions of morphophysiologic signs and ischemic ECG changes (a population study)

Relationships between serum lipid and lipoprotein levels, arterial blood pressure, body weight and age, on the one hand, and coronary heart disease (CHD), on the other, were investigated by means of the main constituents analysis in a Northern Khant population. The pattern of relationship between the parameters in question was similar, by the first main constituent, in males and females, and suggested their age-dependence, unrelated to CHD. The second constituent, as a sum total of the effects of another factor, showed an unbalance between body weight and blood lipids, which was correlated with CHD in males and remained indifferent with respect to CHD in females.     

Reproduction of trematodes in the molluscan host: an ultrastructural study of the germinal mass and brood cavity in daughter rediae of Tristriata anatis Belopolskaia, 1953 (Digenea: Notocotylidae)

Parasitology Research - This study describes the fine structure of the germinal mass in daughter rediae of Tristriata anatis. The germinal mass consists of undifferentiated cells, germinal cells...     

New data on Microphallus breviatus Deblock & Maillard, 1975 (Microphallidae: Digenea) with emphasis on the evolution of dixenous life cycles of microphallids

Infection by intramolluscan stages of Microphallus breviatus Deblock & Maillard, 1975 are common in Hydrobia ventrosa mudsnails in Iceland. Cercariae encyst inside the daughter sporocysts and develop there into metacercariae that become infective for the definitive hosts which are probably charadriiform waders. The adult stage was obtained in 1-day-old chicks that were experimentally infected with metacercariae from naturally infected hydrobians. New data are presented on the morphology and biology of the cercariae, and the adult is described for the first time. Comparisons are made between M. breviatus and closely related species. Differential diagnosis of M. breviatus is given. The morphological specializations in larvae of the hermaphroditic generation of the microphallids accompanying transition from trixenous life cycles to dixenous ones are considered, and the applicability of the term “life-cycle truncation” to microphallids with dixenous life cycles is discussed. Also, reasons for the broad distribution of dixenous life cycles within the family Microphallidae are reviewed.