摘要:

We used a selective DNA amplification technique to detect Epstein-Barr virus (EBV) DNA in peripheral blood mononuclear cells from patients with Kawasaki disease (KD). By means of the polymerase chain reaction EBV sequences were indentified directly in 21 (60%) of 35 KD patients within 2 weeks after the onset of KD. Furthermore, EBV sequences were detected in all of 6 repeatedly tested patients with KD within 3 months after disease onset. In contrast, only 2 (12%) of 17 control DNA samples were polymerase chain reaction positive. These results indicate that an unusual EBV-cell interaction may exist in KD.

ISSN:0300-5526    

DOI:10.1159/000150224

出版商:S. Karger AG    

年代:1992

数据来源: Karger

摘要:

A portal protein-DNA complex was isolated from bacteriophage disrupted in 70% acetic acid. This treatment dissociated most of the phage structural proteins, while the portal protein ring remained attached to the highly condensed naked DNA. In the absence of a headful of DNA, the portal ring was not protected. Purification of the portal ring-DNA complex by density gradient centrifugation showed that a dsDNA fragment of about 40 bp was protected from DNase digestion by this association, suggesting it was internalized within the 140 A long, 20^10 Å in diameter T4 apical channel of the ring dodecamer. A portal ring-DNA complex could be isolated from a number of phages (T4, T7, Phi29), and the end(s) of phage T7 DNA was (were) found to be preferentially associated with the ring complex

ISSN:0300-5526    

DOI:10.1159/000150225

出版商:S. Karger AG    

年代:1992

数据来源: Karger

摘要:

Cell lines of primate origin carry membrane receptors which are specific for echoviruses (EV). The present report describes isolation and characterization of a monoclonal antibody (Mab 143) reacting with the membrane of KB cells. The Mab was selected for its protection of different cell lines from primate origin against the CPE of EV-11. This protection was found to extend to most EV serotypes and to coxsackievirus A9, while the replication of several other picornaviruses was not affected. The fluorecein isothiocyanate labelled Mab did not react with cell lines from bovine, canine, or rabbit origin, but bound specifically to the cell lines from human or simian origin. These results suggest that a unique receptor site is used by most EV serotypes for binding onto and penetration into susceptible cells.

ISSN:0300-5526    

DOI:10.1159/000150226

出版商:S. Karger AG    

年代:1992

数据来源: Karger

摘要:

The purpose of our work was to determine if aerosols of Junin virus can infect rhesus macaques and if the disease is the same as that produced by virus inoculated parenterally. The 6 macaques exposed to the virus by aerosol became acutely ill during the 3rd week after exposure, and all died. Three died by day 21, while the remainder died after 1 month. Junin virus was found primarily in visceral organs of those animals dying before 21 days after infection and in the central nervous system tissues from animals dying later. Histological changes were similar to those reported in rhesus monkeys after parenteral Junin viral infection. Gastrointestinal necrosis, however, was less severe in aerosol-infected animals and the associated septicemia was not seen. High levels of alpha interferon were detected by the 3rd day in all infected macaques. Experimental Argentine hemorrhagic fever induced by aerosol infection in rhesus macaques was similar to that seen after parenteral challenge and mimicked closely the clinical syndrome observed in humans.

ISSN:0300-5526    

DOI:10.1159/000150227

出版商:S. Karger AG    

年代:1992

数据来源: Karger

摘要:

Tomato spotted wilt virus (TSWV) has been reported to be morphologically, molecularly and structurally similar to viruses in the family Bunyaviridae. By various types of enzyme-linked immunosorbent assays (ELISA) and Western blot hybridizations, we tested TSWV with antibodies to 12 viruses in the Phlebovirus genus of this family. Serological relatedness was not found between TSWV and phleboviruses. However, one preparation of antibody to Arumowot virus reacted with a 53-kD protein from healthy plant extracts. Six-day-old adult Toxorhynchites amboinensis mosquitoes were inoculated with purified TSWV. Infectious virus was not detected in any of the injected insects during the 5-week test period. However, TSWV antigens were detected in these mosquitoes by ELISA at the original injected level for at least a week after injection. TSWV antigen concentration began to decrease thereafter, but remained at detectable levels for as long as 5 weeks after injection. However, there was no evidence that TSWV replicated in mosquitoes.

ISSN:0300-5526    

DOI:10.1159/000150228

出版商:S. Karger AG    

年代:1992

数据来源: Karger

摘要:

Human carcinoma of the cervix cell line HeLa, adapted to continuous growth in a protein-free chemically defined medium, was used as substrate for the replication of several human pathogenic viruses. Growth characteristics of the cells designated as HeLa-PF in protein-free 1:1 nutrient mixture of Dulbecco’s modified MEM and Ham’s F-12 supplemented with L-ascorbic acid 2-phosphate were similar to those of the cells grown in a serum-supplemented medium. After 30 months (135 subcultures) in the protein-free medium, HeLa-PF cells were infected with poliovirus types 1, 2 and 3; adenovirus types 2 and 5 and herpes simplex virus type 1. Both adenoviruses and polioviruses developed in HeLa-PF cells titers and showed cytopathic effects comparable to those obtained in conventionally grown and maintained cells; in contrast, significantly lower herpes simplex virus type 1 titers and changed characteristics of the cytopathic effects were observed in HeLa-PF cells. The results show that HeLa-PF cells grown continuously in protein-free medium provide a unique system for the study of virus replicat

ISSN:0300-5526    

DOI:10.1159/000150229

出版商:S. Karger AG    

年代:1992

数据来源: Karger

摘要:

A hordeivirus isolated from horsemint (Mentha longifolia Huds.) was designated as the mentha strain of lychnis ringspot virus (LRSV-M) on the basis of serological relationship with the type strain (LRSV-T) and similarities in nucleotide sequence and properties of genomic and replicative RNAs of the two strains. Four ssRNAs in addition to the three genomic RNAs were encapsidated by LRSV-M coat protein. No genomic sequence similarity was detected between LRSV-M and either barley stripe mosaic or poa semilatent viruses under high stringency conditions, confirming that the hordeiviruses are a group of morphologically similar, but genomically distinct viruses.

ISSN:0300-5526    

DOI:10.1159/000150230

出版商:S. Karger AG    

年代:1992

数据来源: Karger

摘要:

Six measles virus strains were isolated from clinical specimens. They differed from a prototype strain in being incapable to grow in cell lines derived from monkey kidney and having a slower electrophoretic mobility of the hemagglutinin protein and a very low hemagglutination activity.

ISSN:0300-5526    

DOI:10.1159/000150231

出版商:S. Karger AG    

年代:1992

数据来源: Karger

摘要:

The rates of synthesis of phage-coded RNA polymerase upon infection of Escherichia coli by bacteriophages T3 or T7 were measured at different MOIs under permissive and non-permissive conditions. At MOIs from 1 to 15, these rates did not vary appreciably, at MOIs of about 20 there was a slight depression in the synthesis rate. The reason for this absence of a positive gene dosage effect is unknown.

ISSN:0300-5526    

DOI:10.1159/000150232

出版商:S. Karger AG    

年代:1992

数据来源: Karger