RESUMEN

Specimens from patients with gastroenteritis (GE) collected during outbreaks and from sporadic cases reported in the USSR in 1979-1984 were examined by electron microscopy (EM), enzyme immunoassay, rotavirus neutralization test in cell culture. All the winter-spring outbreaks and a considerable number (34.9%) of sporadic GE cases were caused by rotaviruses. The summer-autumn outbreaks were of non-rotavirus nature. In water-borne winter-spring outbreaks in adults, severe forms of GE with signs of dehydration were observed. Among infants, cases of virus-carrier state were detected. The rate of rotavirus detection by EM in winter-spring outbreaks depended on the time of specimen collection and decreased after 4 days from the onset of the disease. Apart from rotaviruses, adeno-, astro-, calici-, coronaviruses, and picornavirus-like particles were detected by EM in feces from GE patients.

Asunto(s)

RESUMEN

The authors describe the results of observation and clinico-laboratory examination of patients during seasonal rises of the rotavirus infection incidence in 5 districts of the Moscow region in 1984-1987. The diseases ran their courses in the form of gastroenteritis and enteritis and were marked by a great number of the grave patterns (42-46%), mainly in children of the first three years of life, by a high percentage (77.5%) of the aggravated premorbid status of patients with the grave patterns. The rotavirus nature of diarrheas was supported by the data of direct electron microscopy, ELISA, and solid-phase coagglutination test. The symptom-complex of the clinical manifestations of rotavirus infection was characterized in detail. The histologic and morphometric data pertaining to two lethal outcomes were discussed. It has been demonstrated that respiratory viral infections, primarily influenza, produced an adverse effect, promoting the formation of the severe patterns and the onset of unfavourable outcomes of rotavirus infection in children.

Asunto(s)

Asunto(s)

Asunto(s)

RESUMEN

A new method of solid-phase analysis of viral antigens in which St. aureus, strain Cowan 1, was used as a label is described. The result of analysis is read visually by bacterial agglutination. The degree of agglutination of the staphylococcal diagnosticum corresponds to the amount of the antigen bound with antibodies immobilized on the solid phase. Staining of Staphylococcus with methylene blue simplifies reading of the results. The method has been shown to be sufficiently simple, specific, sensitive, and may be used for diagnosis of different infections diseases.

Asunto(s)

Asunto(s)

Asunto(s)

Asunto(s)

Asunto(s)

RESUMEN

The mechanism of rotavirus antigen amplification in cell culture was studied by immunofluorescence. Reproduction of human rotavirus in cell culture was shown to begin 6 h after inoculation and to be accompanied by a regular increase in the number of antigen-containing cells. A good correlation with the results of electron microscopic studies was demonstrated. The possibility of reliable detection of rotavirus antigen in cell culture by the fluorescent antibody technique at relatively early intervals after infection has been established.

Asunto(s)

RESUMEN

Several methodical approaches (negative staining, filtration by rotation, modeling, optic diffraction, and filtration of images) were used to study the structure of ther internal capsid of rotavirus and the structure and mutual arrangement of capsomers comprising it. The internal capsid of rotaviruses was shown to be constructed as a skew icosadeltahedron (left) with T-13 and to consist of 12 pentamers and 120 hexamers. The structural units (a total of 780) comprising capsomers are organized into trimers, each trimer participating in the formation of three adjacent capsomers, while each of the structural units is a part of only one capsomer.

Asunto(s)

Asunto(s)

Asunto(s)

RESUMEN

Morphogenesis of human rotavirus was studied by primary green monkey kidney cell culture by electron microscopy, at the levels of the 5th and 12th passage in the cell culture. The initial stages of rotavirus morphogenesis were shown to be associated with cytoplasmic inclusions. Nucleoid or core particles formed in the periphery of the inclusions were transported by budding to endoplasmic reticulum cavities where the final stages of virion maturation occurred. The loss of the outer membrane seems to be a component part of this process. Increasing number of virus passages in the cell culture exerted a certain effect on morphogenetic processes in the infected cells.

Asunto(s)

Asunto(s)

Asunto(s)

RESUMEN

Clinical and serological studies were made in 62 children with various purulent infections, who were placed in the same hospital unit. The precipitation test with the antigen of monkey virus SA-11 showed that diarrhea in 32 of these children was etiologically linked with rotaviruses. The diagnostic titers of virus antibodies were detected in children having diarrhea 5.5 times as frequently as in the control group. The characteristic feature in the clinical picture of this diarrhea was the absence of the severe form.

Asunto(s)

RESUMEN

Cases of acute gastroenteritis with negative bacteriological analyses were examined. Preparations of feces collected from patients in the acute stage of the disease were found by immune electron microscopy to contain typical rotavirus particles forming specific aggregates in the presence of convalescent sera. Examinations of paired acute and convalescent sera of the patients revealed the presence in convalescent sera of specific antibodies neutralizing simian rotavirus SA 11 antigenically related to human rotavirus. The specificity of the antibody was confirmed by their titrations by immune electron microscopy and HI test. Thus, rotavirus etiology of cases of gastroenteritis in various parts of the country was confirmed, and the possibility of specific laboratory diagnosis of such cases using simian rotavirus SA 11 was demonstrated.

Asunto(s)

RESUMEN

Rotavirus was isolated from feces of patients and passaged in green monkey kidney cell subculture using the factors affecting the initiation of infection of tissue culture cells with human rotavirus. The effective factors were found to include the presence of low concentrations of trypsin in the infected culture and virus centrifugation of a cell layer which agreed with the data by Almeida et al. (1978) and Shoub and Bertran (1978) obtained in other cell systems. Immune electron microscopy was used to detect the virus in cell cultures and to prove its specificity.

Asunto(s)