Scrub typhus is an acute febrile disease caused by Orientia tsutsugamushi （0. tsutsugamushi）. We report herein the case of a woman who presented with fever and elevated serum levels of liver enzymes and who was defi...Scrub typhus is an acute febrile disease caused by Orientia tsutsugamushi （0. tsutsugamushi）. We report herein the case of a woman who presented with fever and elevated serum levels of liver enzymes and who was definitively diagnosed with scrub typhus by his- topathological examination of liver biopsy specimens, serological tests and nested polymerase chain reaction. Immunohistochemical staining using a monoclonal an- ti-O. tsutsugamushi antibody showed focally scattered positive immunoreactions in the cytoplasm of some hepatocytes. This case suggests that scrub typhus hepatitis causes mild focal inflammation due to direct liver damage without causing piecemeal necrosis or interface hepatitis. Thus, scrub typhus hepatitis differs from acute viral hepatitis secondary to liver damage due to host immune responses, which causes severe Iobular disarray with diffuse hepatocytic degeneration, necrosis and apoptosis as well as findings indicative of hepatic cholestasis, such as hepatic bile plugs or brown pigmentation of hepatocytes.展开更多
M202, IR50 and advanced backcross （BC4F6） lines carrying the cold tolerance QTLs qCTS4 and qCTS12 were evaluated using three low temperature stress assays （constant, intermittent and constant with recovery period）...M202, IR50 and advanced backcross （BC4F6） lines carrying the cold tolerance QTLs qCTS4 and qCTS12 were evaluated using three low temperature stress assays （constant, intermittent and constant with recovery period）. Under constant stress, two BC4F6 lines （MIb 4853-9 and MIb 6885-2） exhibited differences in seedling growth and accumulation of stress-related compounds although both carry the two QTLs in the IRS0 background. Differences between these lines were also observed in the constant with recovery period assay, although both of them performed comparably under intermittent stress, MIb 6885-2 performed more similarly to M202 in the constant and constant with recovery period assays, suggesting that this line contains an introgressed region（s） not present in MIb 4853-9. The three assays were also applied to assess variations in cold tolerance in a set of diverse germplasms. Performance metrics and visual ratings were comparable for evaluating tolerance to constant stress. However, differences in response to intermittent stress were more evident from growth and total chlorophyll measurements than from visual ratings. With regard to the constant with recovery period assay, about 15% of the germplasm accessions did not recover. However, some lines which exhibited chilling injuries of comparable severity were able to overcome them. This recovery phenotype may improve rice performance in the field and warrant further investigation.展开更多
基金Supported by The Korea Science and Engineering Foundation Grant Funded by the Korean Government through the Research Center for Resistant Cells, No. R13-2003-009
文摘Scrub typhus is an acute febrile disease caused by Orientia tsutsugamushi （0. tsutsugamushi）. We report herein the case of a woman who presented with fever and elevated serum levels of liver enzymes and who was definitively diagnosed with scrub typhus by his- topathological examination of liver biopsy specimens, serological tests and nested polymerase chain reaction. Immunohistochemical staining using a monoclonal an- ti-O. tsutsugamushi antibody showed focally scattered positive immunoreactions in the cytoplasm of some hepatocytes. This case suggests that scrub typhus hepatitis causes mild focal inflammation due to direct liver damage without causing piecemeal necrosis or interface hepatitis. Thus, scrub typhus hepatitis differs from acute viral hepatitis secondary to liver damage due to host immune responses, which causes severe Iobular disarray with diffuse hepatocytic degeneration, necrosis and apoptosis as well as findings indicative of hepatic cholestasis, such as hepatic bile plugs or brown pigmentation of hepatocytes.
文摘M202, IR50 and advanced backcross （BC4F6） lines carrying the cold tolerance QTLs qCTS4 and qCTS12 were evaluated using three low temperature stress assays （constant, intermittent and constant with recovery period）. Under constant stress, two BC4F6 lines （MIb 4853-9 and MIb 6885-2） exhibited differences in seedling growth and accumulation of stress-related compounds although both carry the two QTLs in the IRS0 background. Differences between these lines were also observed in the constant with recovery period assay, although both of them performed comparably under intermittent stress, MIb 6885-2 performed more similarly to M202 in the constant and constant with recovery period assays, suggesting that this line contains an introgressed region（s） not present in MIb 4853-9. The three assays were also applied to assess variations in cold tolerance in a set of diverse germplasms. Performance metrics and visual ratings were comparable for evaluating tolerance to constant stress. However, differences in response to intermittent stress were more evident from growth and total chlorophyll measurements than from visual ratings. With regard to the constant with recovery period assay, about 15% of the germplasm accessions did not recover. However, some lines which exhibited chilling injuries of comparable severity were able to overcome them. This recovery phenotype may improve rice performance in the field and warrant further investigation.
