Biomedical subjects

M E Hardy

Publications and source records attributed to M E Hardy.

10 recordsLinked to original sources

PubMed1992

Amino acid sequence analysis of bovine rotavirus B223 reveals a unique outer capsid protein VP4 and confirms a third bovine VP4 type.

The nucleotide and deduced amino acid sequence of the gene 4 of bovine rotavirus strain B223 is described. The open reading frame is predicted to encode a VP4 of 772 amino acids, shorter than described for any other rotavirus strain sequenced to date. B223 VP4 shows 70 to 73% similarity to other rotavirus VP4 proteins, demonstrating the presence of a unique VP4 type, and confirming a third VP4 allele in the bovine rotavirus population. Multiple sequence alignment with several other rotavirus strains created gaps in the sequence to account for a shorter VP4. The alignment shows a two contiguous amino acid deletions within the trypsin cleavage region of B223 VP4. Comparisons of two regions flanking the trypsin cleavage site, (aa 224 to 235, and aa 257 to 271) which show high homologies between strains, demonstrate that the region 5' to the trypsin cut site has a low homology (66%) to other rotavirus strains, although the region 3' to the trypsin cleavage site shows high homologies (86 to 93%) with other rotavirus strains. The lack of a conserved proline residue within the 5' flanking region suggests a possible altered local conformation of this site in B223 VP4. A second gap inserted into the VP4 of B223 on multiple sequence alignment is a three contiguous amino acid deletion at position 613-615 in the VP5* subunit. Previously defined biologic properties of this strain in relation to the determination of the amino acid composition of VP4 are discussed.

Alleles↗

PubMed1991

Analysis of serotypes and electropherotypes of equine rotaviruses isolated in the United States.

Equine group A rotaviruses isolated over a 10-year period in New York State, New Jersey, Kentucky, and Texas were compared serotypically and electropherotypically. All isolates were determined to be serotype 3 by reaction with hyperimmune antiserum to the serotype 3 H-2 strain of equine rotavirus. All displayed RNA electrophoretic migration patterns related to that of the H-2 strain but distinct from that of serotype 5 strain H-1. A serologic survey of 184 mares in Kentucky, which was done to determine the incidence of H-1 and H-2 infections, showed geometric mean serum neutralizing titers to the H-2 strain of equine rotavirus to be significantly higher than those to the H-1 strain. These data suggest that the serotype 3 H-2 strain is the dominant equine rotavirus in Kentucky and perhaps elsewhere in the United States. We were unable to produce confirmational evidence that the H-1 strain occurs as a natural infection in the United States.

Animals↗

PubMed1991

Comparative amino acid sequence analysis of VP4 for VP7 serotype 6 bovine rotavirus strains NCDV, B641, and UK.

In a previous study (S. Zheng, G. N. Woode, D. R. Melendy, and R. F. Ramig, J. Clin. Microbiol. 27:1939-1945, 1989), it was predicted that the VP7 serotype 6 bovine rotavirus strains NCDV and B641 do not share antigenically similar VP4s. In this study, gene 4 and the VP7 gene of B641 were sequenced, and the amino acid sequences were deduced and compared with those of NCDV and bovine rotavirus strain UK. Amino acid sequence homology in VP7 between the three strains was greater than 94%, confirming their relationship as VP7 serotype 6 viruses. VP4 of B641 showed amino acid homology to UK of 94% but only 73% homology to NCDV. Sequence comparison of a variable region of VP8 demonstrated amino acid homology of 53% between B641 and NCDV, whereas B641 and UK were 89% homologous in this region. These results confirm the earlier prediction that although the same serotype by VP7 reactivity, B641 and NCDV represent different VP4 serotypes. This difference in VP4 may have contributed to the lack of homotypic protection observed in calves, implicating VP4 as an important antigen in the active immune response to rotavirus infection in bovines.

Amino Acid Sequence↗

PubMed1990

Outpatient percutaneous central venous access in cancer patients.

A 1-year experience of percutaneous subclavian catheterization in outpatients with cancer was reviewed to document reliability, safety, and cost. There were 763 catheter insertions attempted with prospective documentation of complications in 664 consecutive patients. Catheter insertion was successful in 722 attempts (95%). There were only 13 pneumothoraces (2%). Thirty catheters required repositioning (4%). The average catheter duration was 191 days (range: 0 to 892 days). Fifty-six catheters (8%) were removed because of suspected infection. Documented catheter sepsis occurred in 21 patients (3%); catheter site infection occurred in 8 patients (1%). Thus, only 0.22 infections per catheter year occurred during this 382 catheter-year experience. The estimated cost of catheter insertion was $562, which is one-third the estimated cost for tunneled catheters ($1,403) and for reservoir devices ($1,738). In our experience, percutaneous subclavian catheterization is a reliable, cost-effective method compared with tunneled or reservoir devices, with an equivalent incidence of catheter-related infections. The cornerstone of our success with this program is a staff dedicated to catheter care and intensive patient education. In centers where a large number of patients require central venous access, percutaneous catheterization should be the technique of choice.

Ambulatory Care↗

PubMed1985