Ninomiya, Yoshifumi

While heat shock protein (HSP) 72 is known as a stress protein, there have been no reports of HSP 72 expression in patients who have undergone surgery for congenital heart disease. Fourteen patients (7 males and 7 females) who had undergone surgery for congenital heart disease were studied. The ages of the patients ranged from 2 months to 43 years old (mean 6.5 +/- 10.8 years old; median 3.0 years old). The diagnoses were Tetralogy of Fallot in seven, pulmonary atresia with ventricular septal defect (VSD) in three, complex anomalies in three, and VSD in one patient. Histological study and HSP analysis using Western blots and immunostaining with anti-HSP 72 monoclonal antibody were performed for right ventricular muscle samples resected during the surgery. The histological findings showed hypertrophic changes of ventricular cardiomyocytes in all samples studied. Western blots detected HSP 72 expression of various degrees in all specimens. Immunostaining using monoclonal antibody against HSP 72 showed that the protein was present in the nuclei and cytoplasm of cardiomyocytes. In conclusion, although it is difficult to determine the cause of the "stress" that triggers HSP 72 expression in cardiomyocytes, low O2 saturation and pressure overload might act as a "stress", and the only common factor that induced HSP 72 in every sample was hypertrophy.

ADAMTS1 (a disintegrin and metalloproteinase with thrombospondin motifs 1) is an inflammatory-induced gene. We have previously reported that ADAMTS1 was strongly but transiently expressed in the infarcted heart. In this study, we investigated whether a 3'-untranslated region (UTR) affects the mRNA stability of this gene. When stimulated with tissue necrosis factor (TNF)-alpha, the expression level of ADAMTS1 mRNA rapidly increased, but the induction of ADAMTS1 mRNA peaked at 6h after stimulation, after which the expression levels of ADAMTS1 mRNA decreased. The 3'-UTR ADAMTS1 mRNA contains multiple adenine and uridine-rich elements, suggesting that the 3'-UTR may regulate gene stability. The addition of actinomycin D, an RNA synthesis inhibitor, demonstrated the decay of induced ADAMTS1 mRNA by TNF-alpha. Furthermore, a region containing multiple AUUUA motifs within the ADAMTS1 3'-UTR destabilized transfected Enhanced Green Fluorescence Protein (EGFP) mRNA expression. These results demonstrated that the ADAMTS1 3'-UTR may regulate the expression of ADAMTS1 mRNA.

We herein determined by fluorescence in situ hybridization the chromosomal localization of 2 human genes, BRAL1 and BCAN, both of which belong to the link-module superfamily, i.e. to the same band of chromosome 1q21-23. Further analysis of the genomic organization of BRAL1 and BCAN revealed that the BRAL1 gene was located 20-kb upstream of the BCAN start site. We isolated a polymorphic dinucleotide (CA) repeat sequence from a genomic clone containing the BCAN gene. High heterozygosity (0.79) makes this polymorphism a useful marker in the study of genetic disorders. Knowledge of the structure of the genes and the marker provides essential information for further analysis of the gene locus at chromosome 1q21-23.

Circulating hepatitis C virus (HCV) particles can be fractionated by means of differential flotation centrifugation. It is reported that in the bottom fraction HCV is in the form immune complexes, whereas in the top, it is free of antibodies. We evaluated the significance of circulating complex and free HCV in chronic hepatitis C, and assessed the relationship in terms of the response to interferon (IFN) therapy. We examined sera before, just after, and 1 year after administering IFN to 18 patients with chronic hepatitis C, 10 of whom responded (group CR), and 8 did not (group NR). The amounts of virus were similar between both groups before therapy. After differential flotation centrifugation with 1.063 g/ml of NaCl, the top and bottom fractions were assayed for HCV RNA. Before therapy, HCV RNA was detected in the top fraction in 1 of 10 in group CR, and in 6 of 8 in group NR (P < 0.05, chi-square test). HCV RNA was positive in the bottom fraction of all samples. In a follow-up study of group NR, HCV RNA was detected in the top fraction in 3 of 8 just after IFN therapy, and in 7 of 8 after 1 year. This study suggests that the presence of HCV in the top fraction can predict a poor response to IFN therapy.