[Acanthamoeba isolated from child thymus: Acanthamoeba growth during cocultivation with human and murine eukaryotic cells and induction of cytopathogenic effect on these cells]. / Nekotorye osobennosti povedeniia in vitro kletok ameby roda Acanthamoeba, vydelennykh iz timusa rebenka: zavisimost' razmnozheniia ot prisutstviia v kul'ture iadrosoderzhashchikh kletok cheloveka i myshi i tsitopatogennoe deistvie na éti kletki.

A cell line of the ameba assigned to the genus Acanthamoeba by morphological and cariotypic signs and by the specific features of its life cycle was isolated from the thymus of a child operated on for heart disease. The line received the name CDHT (Cells Derived from Human Thymus). Actively proliferating mammalian cells maintain the multiplication of Acanthamoeba cells in vitro. Using thymocytes as an example, it was shown that death of these cells occurred through the mechanism of apoptosis. The human thymocytes preincubated with the supernatant obtained through the cocultivation of CDHT and thymocytes may also undergo apoptosis.

[A morphological study of blastocysts in lower monkeys using light microscopy]. / Izuchenie morfologii blastotsist nizshikh obez'ian s pomoshch'iu svetovoi mikroskopii.

The paper shows a high infection of some species of nonhuman primates with blastocysts. Lower rates of infection with this pathogen were observed in younger animals. The blastocysts isolated from Macaca mulatta were microscopically analyzed. The findings indicate a great morphological similarity between the blastocysts of primates and those of man (Blastocystis hominis).

[Acanthamoeba keratitis (literature review and case report)]. / Akantamebnyi keratit (po dannym literatury i sobstvennym nabliudeniiam).

Clinical course, specificities in ophthalmologic and parasitologic diagnosis, drug and surgical treatment of keratitis caused by Acanthamoeba are described for the first time in Russian literature. Experience gained in two-year follow-up of a male patient with the condition who used soft contact lenses for a long time before he fell ill and the foreign literature data prompted the authors describe this disease.

[The diagnosis of Acanthamoeba keratitis. The identification of the first case in Russia]. / Diagnostika akantamebnogo keratita. Vyiavlenie pervogo sluchaia v Rossii.

The first case of keratitis caused by Acanthamoeba in a 28-year-old man who was admitted to a hospital on May 17, 1991 is described in the paper. He wore soft contact lenses for correction of myopia. Acanthamoeba was not initially suspected as the pathogen and diagnosis was delayed for 20 months. Acanthamoeba keratitis was confirmed by the culture of the parasite from corneal graft after the second keratoplasty and by cysts in wet mount with 10% potassium hydroxide and on Gram and Giemsa stain smears. The potassium hydroxide mount provides a rapid diagnosis, which makes the method highly useful in the differential diagnosis in Acanthamoeba and fungal keratitis.

[Cryptosporidium sp. in children with diarrhea in Cuba]. / Cryptosporidium sp. u detei, bol'nykh diareei, na Kube.

During the period from May to September 1987 stools from 200 children (aged 2 months to 4 years) with diarrhoea at Children's Hospital in Havana City were tested for enteropathogens. Three stool samples collected from each patient on alternative days were examined for Cryptosporidium oocysts by direct wet mounts, concentration by the method of Ritchie (formol-ether sedimentation) and by modified Ziehl-Neelsen staining technique. Total prevalence of intestinal parasitoses was as high as 24.5%. Cryptosporidium infection was found in 8% (16 children). Cryptosporidium was the second most commonly detected enteric pathogen overall after Lamblia intestinalis (identified in 10%). In the overwhelming majority of patients Cryptosporidium was the only detectable pathogen (13 cases of monoinfection). In the youngest children Cryptosporidium was the commonest parasite. It is noteworthy that all children who excreted the Cryptosporidium oocysts were exclusively bottle-fed.

[Hygienic evaluation of substrata of contamination of ventilation and air conditioning systems]. / Gigienicheskaia otsenka substratov zagriazneniia sistem ventilatsii i konditsioniravaniia vozdukha.

Modern ventilation and air conditioning systems are complex technological objects in environment which can be sources of health-hazardous factors, including biological ones. Ventilation and air conditioning contact systems with water and partial air recirculation have construction prerequisites for environmental accumulation and dispersal of organic substances of microorganism and anthropogenic origin. Pollution substrates of inner surfaces of the above systems contain specific antigens causing immune response in persons working in air-conditioned premises.

[Possible entry of fragments of a bacterial genome into the trophozoite nucleus of the dysentery amoeba]. / Vozmozhnoe postuplenie fragmentov bakterial'nogo genoma v iadro trofozoita dizenteriinoi ameby.

The use of Fölgen-like electron microscopy reaction has revealed particles in the cytoplasm and nucleus of the dysentery amoeba trophozoites which in their size and resistance to acidic hydrolysis and in their affinity for uranilacetate are similar to tightly packed elements of the bacterial genome. On this basis a conclusion was drawn that some fragments of genomes of phagocytic bacteria can be preserved in the amoebal cell. The community of microorganisms consisting of trophozoites of the dysentery amoeba and bacteria of the intestinal flora is supposed to be a suitable model for studying the possibility of penetration of transgenetic elements from procaryote to eucaryote.

[Morphology of the intranuclear inclusions in Entamoeba histolytica trophozoites]. / Morfologiia vnutriiadernykh vkliuchenii trofozoitov Entamoeba histolytica.

Electron microscope studies of spherical intranuclear inclusions (II) of Entamoeba histolytica trophozoites of two strains, which were maintained in polyxenous culture for different periods of time, were carried out. Data on the number of II in different individuals and in different strains are given. The structure of II whose external layer consists of electron dense material and resembles morphologically peripheral chromatin of the ameba's nucleus, an analogy of nucleolus chromatin of cells of other eucariots, is considered. Inside this layer some II have annular filaments about 9 nm thick rolled up spherically around the central zone of II. Comparison of results obtained and literary data suggests that the dynamic structure of II in question reflects a number of biosynthetic processes on the basis of annular extrachromosomal DNA of exogenic origin.