Molecular identification by RNA-RNA hybridization of a human rotavirus that is closely related to rotaviruses of feline and canine origin.

With a few exceptions subgroup I group A human rotavirus strains have short RNA patterns, whereas most animal rotavirus strains belong to subgroup I and have long RNA patterns. Thus, new isolates of subgroup I human rotaviruses with long RNA patterns are considered to have a high likelihood of being animal rotaviruses. A group of human rotaviruses represented by the AU-1 strain has recently been shown to be genetically related to a feline rotavirus (FRV-1) isolated in Japan.

Rotavirus induces proliferative response and augments non-specific cytotoxic activity of lymphocytes in humans.

In vitro cell-mediated immune responses to rotavirus in humans were studied. Peripheral blood mononuclear cells (PBMC) of healthy adults proliferated in response to stimulation with the infectious and u.v.

Molecular characterization by RNA-RNA hybridization of a serotype 8 human rotavirus with "super-short" RNA electropherotype.

A human rotavirus isolate (the 69M strain) with a "super-short" RNA electropherotype has been classified as serotype 8, a new human serotype [Matsuno et al., 1985]RNA-RNA hybridization using 32P-labeled transcription probes was used to assess the genetic relatedness of the 69M strain to a panel of human and animal rotaviruses. The 69M strain showed a medium level of homology with subgroup 1, serotype 2 human rotaviruses with short RNA electropherotypes.

Presence of three P types (VP4 serotypes) and two G types (VP7 serotypes) among bovine rotavirus strains.

Cross neutralization tests with a panel of rotavirus strains representing previously described nine VP7 (G) serotypes revealed that bovine rotavirus strain KK-3, a prototype Japanese bovine serotype 2, belonged to a new serotype (G10), confirming and extending the recent report of Snodgrass et al. [J. Clin.

Isolation and molecular characterization of a serotype 9 human rotavirus strain.

A human rotavirus strain, designated AU32, that belongs to serotype 9 was isolated and was compared by RNA-RNA hybridization with recently established two serotype 9 strains (WI61 and F45) as well as other prototype human strains. These three strains exhibited a very high degree of homology with one another and shared a high degree of homology with strains belonging to the Wa genogroup but not with strains belonging to either the DS-1 or AU-1 genogroup. These results suggest that genetic constellation of the serotype 9 strains is similar to that of the commonest human rotavirus despite the recent recognition of this serotype.

Identification of rotaviruses by dot-blot hybridization using an alkaline phosphatase-conjugated synthetic oligonucleotide probe.

We have evaluated a recently-developed dot-blot hybridization assay for the detection of human rotaviruses using an alkaline-phosphatase conjugated oligonucleotide probe. The lower detection limit of this assay was 1 ng (approximately 5 x 10(7) copies) of the double-stranded (ds) RNA, when a purified preparation from serotype 1 human rotavirus was used but appeared to be much higher when applied on clinical specimens. This assay could detect dsRNA from rotavirus strains belonging to serotypes 1 through 6, 8 and 9.

[Nosocomial infections and clinical microbiology].

Hospital-acquired infection with strains of methicillin-resistant Staphylococcus aureus (MRSA) have considerably increased in recent years. In addition to being resistant to methicillin, these strains are resistant to practically all forms beta-lactams, aminoglycosides and many other antibiotics. There appears no cost-effective control and preventive measures for this common but also potentially life-threatening disease.

Use of alkaline northern blot hybridization for the identification of genetic relatedness of the fourth gene of rotaviruses.

A recently developed alkaline northern blot hybridization assay (Li, J. K. K.

Identification of rotavirus genogroups by RNA-RNA hybridization.

The genetic relatedness of various human rotavirus strains was examined by RNA-RNA hybridization in which 32P-labelled single stranded RNAs produced by in vitro transcription from viral RNAs were used as probes. Denatured genomic double stranded RNAs were hybridized to the probes under highly stringent conditions and the resulting hybrids were fractionated by polyacrylamide gel electrophoresis. Based on the hybridization patterns obtained with probes made from prototype strains Wa (subgroup II, long RNA electropherotype), DS-1 (subgroup I, short RNA electropherotype) and AU-1 (subgroup I, long RNA electropherotype), we have observed that human rotaviruses fall into three distinct gene groups which we have termed 'genogroups'.

Antigenic and molecular characterization of bovine rotaviruses isolated in Japan.

Japanese bovine rotavirus isolates, which fall into two different serotypes, were shown to belong to subgroup I and to have long RNA electrophoretypes. This study confirmed the distinction of two serotypes on the basis of a greater than 20-fold difference in neutralization titres between the homologous and heterologous reactions; however, significant one-way cross-neutralization was observed between one of the strains with bovine serotype 2 and antisera to strains with bovine serotype 1 (serotype 6 according to the unified serotyping system). When 32P-labelled transcription probes prepared from Japanese strains as well as a prototype NCDV strain were hybridized with genomic double-stranded RNA from these bovine strains and from prototype human strains, a high level of homology was observed among bovine rotavirus strains; but this level of homology was not found between bovine strains and any of the prototype human strains.

Molecular identification of a novel human rotavirus in relation to subgroup and electropherotype of genomic RNA.

A total of 41 stool rotavirus specimens collected from children with acute diarrhea at four different locations in Akita Prefecture, Japan, during the peak of the winter diarrhea epidemic in 1988 were analyzed by polyacrylamide gel electrophoresis of viral RNA in conjunction with subgrouping assay. We found that a single strain predominated, with cocirculating strains with less common electropherotypes at a given location, and that two different strains could predominate at geographically close but different locations even during a very limited time of the epidemic season. Furthermore, we isolated a human rotavirus strain (AU125) that was similar to the AU-1 strain in that it possessed a long RNA pattern yet belonged to subgroup I.

[Experiences of postoperative staphylococcal enteritis caused by methicillin-cephem resistant Staphylococcus aureus (MRSA) and the state of the isolation of MRSA].

During the last 12 months, three cases of postoperative staphylococcal enteritis were experienced in our surgical ward. Kanamycin, Clindamycin and Latamoxef were given prophylactically in all cases. They developed dehydration with severe diarrhea and paralytic ileus in three to ten days after abdominal surgery.

RNA-RNA hybridization identifies a human rotavirus that is genetically related to feline rotavirus.

A human rotavirus AU228 strain which resembled the AU-1 strain (O. Nakagomi, T. Nakagomi, Y.

Characterization of a canine rotavirus strain by neutralization and molecular hybridization assays.

A canine rotavirus, RS-15, previously isolated in Japan was determined to be subgroup I and serotype 3. When compared with prototype human and animal rotavirus strains by RNA-RNA hybridization assay, the RS-15 strain showed a high degree of homology only with the canine CU-1 strain isolated in the United States of America, suggesting that canine rotaviruses constitute a distinct gene family, which we have elsewhere proposed to term "genogroup".

Occurrence of changes in human rotavirus serotypes with concurrent changes in genomic RNA electropherotypes.

To investigate the serotypic and genetic diversity of human rotavirus strains, we have tested 513 and 519 fecal rotavirus specimens, respectively, by an enzyme-linked immunosorbent assay with serotype-specific monoclonal antibodies and by polyacrylamide gel electrophoresis of the segmented RNA genome. Of the 513 specimens, 375 were typed as serotype 1 (47.3%), serotype 2 (2.

Serologic characteristics of a human rotavirus isolate, AU-1, which has a "long" RNA pattern and subgroup I specificity.

An unusual human rotavirus (HRV) isolate, designated AU-1, has a "long" RNA electrophoretic pattern and subgroup I specificity, in contrast to properties common to HRVs previously isolated. Hemagglutination activity of the AU-1 strain was demonstrated using erythrocytes of 1-day-old chicken. Neutralization assays revealed that the AU-1 strain was crossneutralized by hyperimmune antisera against the MO strain (serotype 3).