Biomedical subjects

M Yu

Publications and source records attributed to M Yu.

453 records · Page 26Linked to original sources

PubMedDate not supplied

Viral agents associated with poult enteritis and mortality syndrome: the role of a small round virus and a turkey coronavirus.

Intestinal samples from turkey poults affected with poult enteritis and mortality syndrome (PEMS) were examined for viruses by immune electron microscopy and double-stranded RNA virus genome electropherotyping. Turkey coronavirus (TCV), avian rotaviruses, reovirus, and a yet undefined small round virus (SRV) were detected. The SRV and TCV were isolated and propagated in turkey embryos. Challenge of specific-pathogen-free turkey poults with SRV, TCV, or both resulted in mortality and clinical responses similar to those of natural PEMS. Our experiments indicate that SRV and TCV are possibly important agents in the etiology of PEMS and the combination of these infections might result in outbreaks with high mortality. The severity of clinical signs and mortality of PEMS are postulated to be partly related to the virus agents involved in individual outbreaks.

Animals↗

PubMedDate not supplied

Characterization of a small round virus associated with the poult enteritis and mortality syndrome.

A small round virus (SRV) identified and isolated in our laboratory from intestinal samples of poults affected with the poult enteritis and mortality syndrome was further characterized. The SRV was propagated in turkey embryos and purified by differential and isopycnic ultracentrifugation. The size of the SRV was 30-32 nm in diameter. The buoyant density of the SRV in cesium chloride was between 1.34 and 1.36 g/cm3. It was resistant to chloroform treatment, stable at pH 3.0, and resistant to heat treatment. Attempts to propagate the SRV in turkey embryo kidney, turkey kidney, Caco-2, Vero, and BGM-70 cells were unsuccessful. Analysis of the SRV capsid proteins by sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed three polypeptides with molecular weights of 34.5, 31, and 28 kD. Genome analysis of the SRV showed that the SRV had a single-strand RNA genome about 7500 nucleotides in length. Reverse transcription-polymerase chain reactions (RT-PCRs) with primers specific to conserved sequences of enteroviruses yielded products with expected sizes. However, sequence analysis of the RT-PCR products showed that there was no similarity between the sequences and that of enteroviruses. RT-PCR with primers specific to the 3' end of a SRV RNA genome yielded products with expected sizes. These products were sequenced and found to contain 669 nucleotides, excluding the polyadenylated tail. Sequence analysis indicated that the SRV shared 38.18% amino acid identity in the C-terminal capsid precursor protein and 41.26% nucleotide identity of the 3' end of turkey astrovirus RNA genome (Genbank accession no. Y15936). We concluded that the SRV is a member of the astrovirus family.

Amino Acid Sequence↗

PubMedDate not supplied

Transjugular intrahepatic portosystemic shunts: midterm results in 28 patients.

This paper reports the clinical and procedural results of 28 consecutive TIPS procedures in 25 males and three females with a mean age of 48 years. All patients had cirrhosis with portal hypertension and varices. Twenty-two patients had recurrent bleeding. Shunts were completed in 26 of 28 patients, and no death was associated with the procedure. Portal vein pressure was reduced from 3.98 +/- 0.24 KPa before shunting to 2.40 +/- 0.16 KPa after shunting. Doppler US revealed that the maximum blood flow velocity in the main portal vein increased from 14.0 +/- 4.5 cm/sec to 48.0 +/- 16.5 cm/sec. Shunt patency was determined by color Doppler US in 20 patients. Shunt stenosis was found in five patients and occlusion in one, and these findings were confirmed by angiography. Ascites disappeared in six of eight cases, and varices disappeared completely in 11 patients and abated greatly in 12 patients two months after TIPS. Rebleeding occurred in three cases (occlusion, 1; stenosis, 2) during a mean follow-up time of 6.5 months. One of these cases was successfully redilated. The initial results suggest that TIPS is a safe and effective method of portal decompression and that the key to portal vein puncture is to understand the three-dimensional relationship between the hepatic and portal veins.

Adult↗