Biomedical subjects

Masatomo Hayashi

Publications and source records attributed to Masatomo Hayashi.

3 recordsLinked to original sources

PubMed2004

Primary peritonitis associated with streptococcal toxic shock-like syndrome: report of a case.

Several reports over the past 15 years describe severe group A streptococcal infections causing septic shock, soft-tissue necrosis, and multiple organ failure; a phenomenon known as streptococcal toxic shock-like syndrome (TSLS). However, primary peritonitis associated with TSLS is rare. We report the case of a 40-year-old man admitted with pain in both thighs, hypotension, and severe abdominal pain. His daughter had been diagnosed with streptococcal pharyngitis 3 days earlier. We performed an emergency laparotomy for peritonitis, and culture of the ascites was positive for group A beta -hemolytic streptococcus (GAS). Further serotyping of the isolated GAS strain revealed the T-type 22 and the pyrogenic exotoxin gene, spe-C. The criteria for TSLS were clearly met, including the isolation of GAS from ascites, hypotension, liver failure, renal failure, coagulopathy, myositis, and a generalized erythematous macular rash with desquamation.

Acute Disease↗

PubMed2003

Analysis of the T cell receptor V beta repertoire in 2,4,6-trinitrobenzenesulfonic acid induced colitis in mice.

The aim of this study was to analyze which types of T cells are at work and the specific nature of their response, using a mouse 2,4,6-trinitrobenzenesulfonic acid (TNBS) induced colitis model. The response of T cells to TNBS was analyzed by anti-TNBS mixed-lymphocyte reaction. T cell clones were established by limiting dilution. Phenotypes and T cell receptor (TCR) V beta of T cells were analyzed by flow cytometry. Colitis was induced by administration of TNBS enemas, and lamina propria lymphocytes were isolated and analyzed. The proliferative responses to TNBS of spleen T cells were partially inhibited by the addition of antimouse CD4 or CD8 antibodies to the mixed-lymphocyte culture. Conversely, these were inhibited by the addition of both antibodies. Flow cytometric analysis showed that TCR V beta 14 T cells specifically increased in the CD8+ T cell population. We established CD8+ TCR V beta 14 T cell clones which were TNBS reactive and self-restricted. Investigation using lamina propria lymphocytes in TNBS-induced colitis revealed that the rate of CD8+ TCR V beta 14 T cells changed with histological inflammatory activity which also attained a peak on day 5 following enema administration. Both CD4+ and CD8+ T cell subsets responded to TNBS, and the rate of CD8+ TCR V beta 14 T cells changed with histological inflammatory activity in TNBS-induced colitis.

Animals↗

PubMed2002

Dielectric spectrogram for evaluating ischemic microstructural changes of the liver in simple cold preservation.

PURPOSE: Monitoring ischemic liver injury is important in liver transplantation. We previously reported that dielectric properties were correlated with tissue adenosine triphosphate during liver preservation; however, it is unknown what the changes in dielectric properties are based on. Using rats, we studied the relationship between dielectric parameters and microstructural changes in liver tissues during preservation. METHODS: We serially measured the percent decrease in conductivity and the percent increase in relative permittivity in rat livers, and determined the areas of cellular and extracellular components using a charge-coupled device microscope and an NIH image. Thereafter, we evaluated the relationship between dielectric parameters and microstructural changes in the liver tissues. RESULTS: A positive linear and exponential correlation was found between the percent decrease in conductivity and the percent decrease in extracellular components ( P < 0.01). A positive linear and exponential correlation was also found between the percent increase in relative permittivity and the percent increase in cellular components ( P < 0.01). CONCLUSIONS: Our results suggest that the serial changes in tissue conductivity and the relative permittivity reflect changes in liver tissue microstructures during cold preservation.

Animals↗