The Japanese journal of experimental medicine最新文献

The oedema produced in the mouse by intraplantar injection of the venom of Trimeresurus flavoviridis was inhibited by morphine (Mo) and by naloxone (Nx); the action of Mo increased with the dose, whereas that of Nx first progressed and thereafter regressed with the dose; very small doses of Nx antagonized Mo. Methylnaloxone (MeNx), a quaternary ammonium derivative of Nx was much less effective than Nx by the subcutaneous route but almost as effective by the intraplantar route. Peripheral opioidergic receptors are thus likely to be involved. Very high doses of Mo acted an synergistically with an optimal dose of EDTA or zymosan; complex interactions occurred between lower doses of Mo or Nx and EDTA or zymosan.

An enzyme-linked immunosorbent assay was developed for the determination of antibodies against the putative capsid protein of hepatitis C virus (HCV). A 36-mer oligopeptide with a sequence of RRGPRLGVRATRKTSERSQPRGRRQPIPKVRRPEGR (CP9) was synthesized; it was selected on the translation product of the presumptive HCV core gene, because of a high local hydrophilicity and excellent conservation by different HCV strains. The synthetic peptide was immobilized on a solid-support to capture antibodies directed to CP9 (anti-CP9) in test sera, which were detected by Fab' fragments of monoclonal anti-human IgG/gamma labeled with horseradish peroxidase. The specificity of anti-CP9 was confirmed by absorption tests. Anti-CP9 was detected in 13 (68%) of 19 patients with sporadic acute non-A, non-B (NANB) hepatitis and in 15 (83%) of 18 patients with post-transfusion acute NANB hepatitis. In 7 cases of acute NANB hepatitis who were followed, anti-CP9 developed earlier than antibodies against HCV (anti-HCV) detectable by a commercial assay kit. Among patients with chronic NANB liver diseases, anti-CP9 was detected in 103 (77%) of 133 with chronic hepatitis, 70 (62%) of 113 with liver cirrhosis and 31 (76%) of 41 with hepatocellular carcinoma. Anti-CP9 and anti-HCV overlapped in 175 (54%) among 324 cases of acute or chronic NANB liver diseases; 58 (18%) were positive only for anti-CP9 while 49 (15%) were positive only for anti-HCV. HCV RNA was detected, by amplifying HCV cDNA with polymerase chain reaction, in 10 of 11 sera positive only for anti-CP9. Among sera from 606 blood donors, 21 were positive only for anti-CP9. HCV RNA was detected in 5 (24%) of them, all of which had A492 values greater than 0.600 in ELISA for anti-CP9. Based on these results, anti-CP9 would complement anti-HCV for the diagnosis of HCV infection and contribute toward further decreasing posttransfusion NANB hepatitis.

Transmission of Rickettsia tsutsugamushi (Rt) from a rodent to trombiculid mites was studied. Wild rodents, Apodemus speciosus, were subcutaneously inoculated with Karp strain of Rt, and larval trombiculid mites were released on the ear lobes for feeding, 10 and 20 days after infection. Isolation of Rt was performed from individual mites or pools of 2 to 7 mites by the mouse passage method. From Apodemus 10 days after Rt infection, possibly at the time of high rickettsiaemia, the infection rates among mites were 4/44 (9.1%) or higher in Leptotrombidium fuji, 1/20 (5%) in L. pallidum and 0/41 in L. deliense. From Apodemus 20 days after infection, no mite was infected in 50 L. fuji or 7 L. pallidum possibly due to reduced rickettsiaemia. Transmission of Rt from rodent to mite was proven to occur at low probability on appropriate conditions but not by the incidental chance.

The 5'-terminal sequence of the genome of hepatitis C virus (HCV) was determined for two distinct HCV strains in human and chimpanzee carriers. It had a 5'-noncoding region of at least 324 nucleotides, well preserved by the two strains with a high homology (99.1%), followed by 1348 nucleotides that continued to the documented sequence of prototype HCV spanning 7310 nucleotides (European Patent Application #88310922.5). Based on these results, HCV is considered to possess an uninterrupted open reading frame encoding at least 2886 amino acid residues. Two structural genes were postulated on the 5'-terminal sequence of the HCV genome. One gene in the upstream region, highly conserved by the two strains at the amino acid level and rich in basic amino acids such as arginine, appeared to encode the viral capsid protein. The other gene in the downstream region was divergent between the two strains at both nucleotide and amino acid levels. It coded for nine potential N-glycosylation sites, and was considered to encode the viral envelope protein. Disclosure of the 5'-terminal sequence of the HCV genome would facilitate its taxonomic classification, and contribute toward immunological diagnosis of infection and development of vaccines.

The Nansei Islands are located in the subtropical zone of the western Pacific Ocean between Kyushu and Taiwan, and are composed of the two main island groups, the Amami and the Ryukyu Archipelagoes. This area has been known for the presence of a number of indigenous animal species. Prior to the present studies, collections of the chironomids mainly in the urban areas of the three main islands of the Ryukyus were carried out by Sasa and Hasegawa, and a total of 42 species, including 25 new species, were recorded. Additional collections of the chironomids mainly in the mountainous areas of this region were carried out by the present author during 1988 and 1989, and a total of 26 species (including 12 new species) were recorded from Amami Island, and a total of 27 species (including 10 new species) were recorded from the Ryukyu Islands. Eight species among them, including 3 new species, were common to the two archipelagos.

The proliferative response of peripheral blood CD4+ T cells to recombinant hepatitis B core antigen (rHBcAg) has been studied in patients with chronic active hepatitis (CAH) type B (CAH-B), CAH-nonA nonB, and normal volunteers. CD4+ T cells from patients with CAH-B indicated a significant proliferative response to rHBcAg in the presence of non-T antigen presenting cells. In contrast, there was no apparent T cell reaction to rHBcAg in patients with CAH-nonA nonB and healthy volunteers. We suggested the possibility of CD4-mediated HBcAg specific response even in the peripheral blood compartments of HBcAg-responsive CAH-B patients.

The aorta and the kidney of 12 month old hyperlipidemic WHHL and obese Zucker rats, were examined morphologically. The WHHL developed severe and premature atherosclerosis but did not develop glomerulosclerosis. In contrast, the Zucker rats did not manifest atherosclerosis of the aorta, but developed glomerulosclerosis. These two animal models could be useful in understanding the roles of heterogeneous lipoprotein particles, genetic susceptibility, hemodynamic stress, and mesangial interactions with lipoproteins in the development of glomerulosclerosis.