[OPISTHORCHIASIS AS A PROMOTER OF GASTRIC CARCINOGENESIS].

The paper presents an experimental model of gastric cancer in the presence of chronic opisthorchiasis, which has been created to study its possible role in gastric carcinogenesis. The performed investigation has supported the hypothesis that opisthorchiasis plays a promoting role in the development of experimental gastric cancer. A larger number of experimental hamsters receiving the carcinogen methylnitronitrosoguanidine (MNNG) developed earlier gastric tumors in. the presence of chronic opisthorchiasis than the control animals in the experiment.

[The strategy of a parasite is to preserve and continue its species; some trends for achieving the goal].

The authors show that the strategy of parasites, which is to preserve and continue its species is accomplished mainly by providing of a trophic substrate. Opisthorichiasis is used as an example to show that the nutriceutic biomass of cholangiocytes may be increased due to gene mutations, induced proliferation of liver stem cells, their differentiation to committed ones and cholangiocellular differon elements; moreover, the proliferative processes of mesenchymal components become active in other organs of a host. During their ontogenesis in the intermediate and final hosts, the parasites work out the mechanisms for prolonging their life span to complete a full development cycle (Margaritifera margaritifera glochidia); however, predominantly the parasite-host symbiosis is attended by the latter's lameness. Predation is one of the types of symbiotic relations.

[Complicated forms of superinvasion opisthorchiasis: pathogenetic aspects].

Superinvasion opisthorchiasis is characterized by host growth retardation and weight reduction, which are due to the cleptoeffect of Opisthorchis felineus; metabolic disturbances, proliferative processes, accelerated collagen biosynthesis and biodegradation in the organs reflect parasite-host interactions as components of the system. The productive reactions of visceral pathology are initiated by the parasite's metabolites located in the liver, lung, heart, and testes.

[The specific features of regenerative processes of hip and shin fractures in patients with superinvasion opisthorchiasis].

Opisthorchis superinvasion retains the natural manifestations of reparative regeneration of skeletal tissues, but activates proliferation stages and increases the promoter manifestations of histogenesis. Irrespective of a surgical option, the rate of infestation, and the place of residence, reparative regeneration of shaft fractures of the shin and hip occurs significantly more rapidly in patients with superinvasion opisthorchiasis than in those without the latter. In superinvasion opisthorchiasis, bone is restituted by early callus formation and accelerated regenerate mineralization.

[Provisionality phenomenon in the histo- organo- and systemogenesis].

This review summarizes the results of the study of the provisionality phenomenon in the development of the organs of the urinary system (mesonephros, metanephros) in viviparous (human, rat) and oviparous (bird) amniotes, human organs of mixed origin (pituitary, ovary, stomodeum) reparative regeneration of supporting tissues (in humans and Syrian hamster), morphogenesis of primary hepatic cancer developing against the background of superinvasive opisthorchiasis. It is shown that during the development of tissues and organs, the stages of provisional and definitive histo- and organogenesis could be determined; saltatory mechanism is typical for embryonic organogenesis (formation of cartilaginous skeletal primordia, meso- and metanephrons) and foci of oncogenesis. Transformation zones of the type of tissue organization in the epithelium are located in the areas of contacts of the derivatives of different embryonic primordia. Mechanism of transformation of the epithelial layer of stomodeum and Rathke's pouch is provided by local activation of apoptosis and by the formation of the epithelial cells of a qualitatively new generation.

[Morphogenesis of the structural changes of the internal organs in superinvasive opisthorchiasis].

The study of the model of superinvasive opisthorchiasis (SO) in Syrian hamsters and autopsy material obtained from patients with SO, it was shown that during the early period of pulmonary disease, the lungs underwent changes developing on the basis of delayed-type hypersensitivity reactions. In the chronic phase of SO, exudative and predominant productive reactions were revealed leading to the interstitial lung disease, fibrosing alveolitis. In the heart in SO, eosinophilic cell myocarditis was found with subsequent diffuse cardiosclerosis. In the testes, sclerotic processes with atrophy of glandulocytes (Leydig cells) and sustentocytes (Sertoli cells) were detected. The structural changes in the lungs, heart and testes were induced by parasite metabolites, that are deposited in tissues in the form of granules and conglomerates.

[Quantitative characteristics and specific features of the echographic pattern of the liver and biliary area in opisthorchiasis of a hyperendemic focus].

One hundred and twenty-three patients from a hyperendemic focus underwent ultrasound study. The anteroposterior size of the liver, the thickness of the wall of the gallbladder and the nature of its contents, the diameter of common bile ducts and portal vein, additional morphological changes in the architectonics of the liver and biliary ducts were determined. Examinations have established that ultrasound study is a technique determining the characteristic signs that are pathognomic to moderate and severe invasions--cholangiectases (predominant localization in the second segment of the liver), a significant increase in the anterioposterior size of the liver and an change in the parenchyma of the organ, the thickening of the wall of the gallbladder, an change in its content (at the expense of sediments, flocculi, waxes, and concretions), and an increase in the size of the intrahepatic and common bile ducts.

[Hepatic cell transformation changes in experimental opisthorchiasis].

Changes in the liver where Opisthorchis felines (Rivolta, 1884) parasitizes were traced by light and transmission electron microscopies on experimental models (gold hamsters) of acute and chronic opisthorchiasis. Regenerative processes, such as hepatic epithelial mitotic indices, binucleated, hypertrophic hepatocytes, were determined; the composition of infiltrates was identified; fibroplastic changes and hepatocytic apoptotic index were traced. The progression/regression (P/R) ratio was used to detect atrophy of a hepatic parenchymatous component (hepatocytes) in different periods (from 3 to 120 days) of invasion. In opisthorchiasis, proliferation of committed hepatocytes was first found on day 10 of invasion. Oval (committed) cells are differentiated mainly to cholangiocytes, followed by the formation of ductular structures; the committed cells of the liver may be simultaneously a source of programmed hepatocellular differentiation; however, the newly formed hepatocytes are solitary amongst them in opisthorchiasis.

[Molecular genetic approaches in parasitology (in case of opisthorchiasis)].

Light, electron microscopy, polymerase chain reaction (PCR), and immunohistochemistry were used to reveal the proliferative, alterative processes of hepatic parenchymal cells, P 53, K-ras, B-raf, c-Kit, p 16, APC, immunoreactive proteins Ki-67, cytokeratins 9, 14, 20, EMA, c-erb B-2, CD-117, mutated p 53 and bcl-2 genes. P53, K-ras, B-raf, c-Kit, and p 16 gene mutations were detected in the liver of animals with experimental superinvasive opisthorchiasis (SO) and cholangiocellular carcinoma (CCC). Mutations of these genes were found in the plasma samples taken from SO patients. The CCC tissue from SO patients displayed expression of the following genes: p 53 (100.0%), p 53+B-raf (50.0%), K-ras+c-Kit (33.3%), K-ras+B-rafat more than 5 cm from the tumor in 2 cases. Following 2 years, target therapy (canglait, megamin, immunomodulators) leveled mutations in 91.25% of the patients with SO.

[Opisthorchiasis in the Ob-Irtysh river basin: etiology and pathogenesis].

Opisthorchiasis in the hyperendemic focus (Ob-Irtysh river basin) is considered to be a co-member of parasitocenosis: opisthorchiasis + methorchiasis and to have a superinvasive form. The symbiotic flora and O. felines metabolites are an etiopathogenetic flora. Scientific evidence is provided for the recurrent forms ofopisthorchiasis; the authors consider it to be the type of superinvasive opisthorchiasis, in which some portion of parasites in microballs unexposed to antheminthics further mature to maritae.

Tissue reactions to modern suturing material in colorectal surgery.

Morphological changes in the wall of the large intestine were studied after its manual suturing by a double-row interrupted suture with modern suture threads. Light and scanning electron microscopy showed "fuse properties" and "sawing effect" of polyfilament twisted threads (e.g. vicryl). Monofilament threads were free from these drawbacks and therefore were preferable. Metal elastic threads on the basis of titanium-nickelide alloys caused no inflammatory changes in tissues.

[Duodenogastroesophageal reflux disease as a complication of superinvasion opisthorchiasis]. / Duodenogastroézofageal'naia refliuksnaia bolezn' kak oslozhnenie superinvazionnogo opistorkhoza.

In patients with superinvasion opisthorchiasis of prolonged invasion, 84% develop duodenal hypertension, 94% of the patients are found to have gastric hypertension; duodenogastric reflux with formation of chronic gastritis and reorganization is revealed in 75%. Reflux of gastric contents into the esophagus gives rise to chronic eosophagitis, regurgitation of intestinal contents into the pancreatic duct is a cause of chronic indurative pancreatitis of the head of the gland. In cases of duodenal hypertension, the rates of pancreatic O. felineus invasion are as high as 93.7%.

[N-nitrosodiethylamine-induced changes in the liver of syrian hamster with superinvasive opistorchiasis]. / Izmeneniia v pecheni khomiachkov, indutsirovannye n-nitrozodiétilaminom pri superinvasionnom opistorkhoze.

Trematoda O. felinius-induced hepatic lesions were investigated in Syrian golden hamsters with superinvasive opistorchiasis. One hundred hamsters were divided into 4 groups: (1)--control; (2) N-nitrosodiethylamine (DENA), i.p., twice a week, 3 weeks, total dose 72 mg/kg; (3) metacercariae O. felinius, with drinking water, 3 injections per day, once in 2 weeks, and (4) metacercariae O. felinius, as in group 3, followed by DENA, as in group 2. Animals were sacrificed 12 months after the beginning of the study. No changes in the liver were found in group 2. Reddish protrusions, up to 4 cm in diameter, appeared on liver surfaces in groups 3 and 4. Group 4 featured the highest relative and absolute weights of liver as well as clusters of oval cells and cholangiocellular tubules and cholangiofibrosis (in group 3, they were less visible). Electron microscopic examination identified hepatocytes with destructive changes to plasmalemma, nucleus and cytoplasmic organelles. Also, perisinusoidal cells (Ito cells) occurred. Tumor-bearing animals showed low hepatic cytochrome P-450. It is suggested that proliferative growth in the liver was stimulated by opistorchis invasion.

[The decreased susceptibility of Syrian hamsters to Opisthorchis felineus invasion after its repeated administration]. / Snizhenie vospriimchivosti siriiskikh khomiakov k invazii Opisthorchis felineus posle povtornogo vvedeniia.

The investigations conducted on Syrian hamsters have revealed that multiple enteral infusions of cold inactivated (t = -10 degrees C) O. felineus metacercariae resulted in the formation of immunocompetent cell and fibroblast infiltrations around the branches of the portal vein. The infestation of animals by viable pathogens led to reduced accommodation of helminths and suppressed cell infiltration in the liver. It is assumed that the native population of the foci become tolerant to the disease with the penetration of noninvasive Opisthorchis larvae into their body and the development of latent forms of helminthiasis.

[A comparative study of the efficacy of praziquantel and its liposomal form in experimental opisthorchiasis]. / Sravnitel'noe izuchenie éffektivnosti prazikvantelia i ego liposomal'noi formy pri éksperimental'nom opistorkhoze.

Intensive and extensive efficacy of praziquantel pure and that included in multilamellar liposomes was studied. As a result, a high anti-helminthic activity of liposomal praziquantel has been established. Negative effect of praziquantel on protein synthetic and enzymatic function of the liver has been revealed in normal animals. The treatment with liposomal praziquantel led to a rapid normalization of total lipid and bilirubin levels, thymol turbidity test, transaminase indices and also to a decrease in dystrophic liver changes.

[The problem of the carcinogenicity of parasites]. / Problema onkogennosti parazitov.

Based on the reported data and their own experience the authors defined the role of carcinogenic parasites in tumorigenesis as promoters. The investigators supposed that a many-year invasion that caused a permanent proliferation of cellular elements and immune suppression were the criteria for carcinogenicity of parasites.

[A comparison of the count of Opisthorchis in the body of the host and of the eggs eliminated with the feces]. / Sopostavlenie chisla opistorkhisov v organizme khoziaina i vydeliaemykh iaits s fekaliiami.

The study of the intensity of Opisthorchis infestation by counting the amount of the parasites in the liver of 62 corpses and 12 cats and the quantity of the parasite's eggs per g feces was carried out. Furthermore, the number of the eggs depending on the intensity of the infection was counted. The fact of irregular distribution of eggs in the colon content and the lack of correlation between the quantity of parasites in the liver and egg contents per g was revealed. An increase in egg production in cases with severe pathology independent of its form was observed in spite of low intensity of invasion.

[Complex assessment of iatrogenic diseases]. / Kompleksnaia otsenka iatrogenii.

Examination of data from 1042 autopsies and case records enabled the authors to schematically systematize iatrogenies and to divide them into 6 types: Group I iatrogenies, true iatrogenies, minus-signed iatrogenies, iatrogenic episodes, background and concurrent iatrogenies. They also singled out outpatient, emergency, and inhospital iatrogenies; preventive, diagnostic, and therapeutic ones; fatal and non-fatal; operational, medicamentous, bioptic, etc.; according to the specialization, the author distinguished surgical, therapeutic, psychiatric, organizational, etc. iatrogenies. Iatrogeny was proposed as a criterion for assessing the activities of medical workers and health services.