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Background: A number of QTL studies reported that one genomic region was associated with several traits, indicating linkage and/or pleiotropic effects. The question of pleiotropy versus tight linkage in these studies should be solved using a large-size population combined with high-density mapping. For example, if each of the 2 parents has a TGW-increasing or SPP-increasing QTL that is tightly linked, complementary combination of the 2 beneficial QTLs by using molecular markers could produce higher yields compared to the 2 parents. However, a pleiotropic QTL with opposite effects on the SPP and 1,000-grain weight (TGW) is complicated and challenging in terms of its application to rice improvement. Results: In this study, using a series of BC 5F 4 nearly isogenic lines (NILs) that were derived from a cross between the Korean japonica cultivar Hwayeongbyeo and Oryza rufipogon, we demonstrated that 2 QTLs, qSPP5 for spikelets per panicle (SPP) and qTGW5 for grain weight (TGW), are tightly linked on chromosome 5. Alleles from the O. rufipogon parent increased the SPP and decreased TGW in the Hwayeongbyeo background. qSPP5 was located within a 803-kb interval between the simple sequence repeat (SSR) markers INDEL3 and RM18076. Based on the map position, qTGW5 seemed to be the same gene as qSW5, which controls grain morphology. The additive effect of the O. rufipogon allele at qSPP5 was 10–15 SPP, and 33.0% of the phenotypic variance could be explained by the segregation of the SSR marker RM18058. Yield trials with BC 5F 4 NILs showed that lines that contained a homozygous O. rufipogon introgression at the qSPP5 region out-yielded sibling NILs that contained Hwayeongbyeo DNA by 15.3% and out-yielded the Hwayeongbyeo parent by 7.3%. Conclusion: Based on the finding that the O. rufipogon allele for the SPP was beneficial in the japonica and indica cultivar backgrounds, the qSPP5 allele could be valuable for improving rice yields. In addition, the NIL populations and molecular markers are useful for cloning qSPP5. [ABSTRACT FROM AUTHOR]

Background/aims: To describe and compare the demographic and clinical characteristics of hepatocellular carcinoma (HCC) patients subject to surgical operation at two referral centers in China and Japan., Methodology: Information on surgical HCC patients was retrieved from medical records. All patients were subjected to regular follow-up. The characteristics of HCC cases from two countries were described and compared., Results: A total of 353 newly diagnosed cases subject to surgical resection for HCC from 1995 to 1999 were analyzed in China and Japan. Differences were noted in the demographic and clinical characteristics of HCC patients between the two countries, such as average age of incidence, history of blood transfusion, serum examination, and history of hepatic viral infection. Statistical analysis also indicated differences in surgical systematic anatomical resection (p < 0.001), liver cirrhosis (p < 0.05), tumor diameter, and distant metastases (p < 0.001). The Chinese patients in early TNM stage I showed poorer outcomes in terms of cumulative survival in comparison with Japanese patients (p < 0.001)., Conclusions: HCC patients in Japan were diagnosed earlier, subject to more standard treatment, and had better prognosis. Examination with a larger population and more clinical data, including repeated treatment for recurrent HCC, will be required to provide a more accurate assessment of HCC in the two countries.

Objective: To describe and compare the hepatitis virus infection in hepatocellular carcinoma (HCC) patients receiving surgical operation in China and Japan., Methods: Information of surgical HCC patients was retrieved from the medical records. The concerned characteristics of the HCC cases from two countries were described and compared., Results: A total of 425 diagnosed cases that underwent surgical resection for HCC in China were investigated, and the corresponding cases in Japan were 247. The proportion of the hepatitis virus infection was 75.53% in patients with HCC from China. Within the infection cases, 91.28% were positive for HBsAg but negative for anti-HCV. The proportion was 82.59% in patients with HCC from Japan. Within the infection cases, 77.94% were positive for anti-HCV but negative for HBsAg. The proportion of hepatocirrhosis in the hepatitis virus infection patients with HCC were 89.10% and 68.14% in China and Japan, respectively., Conclusion: The hepatitis B virus infection showed be a main cause of HCC in China, however, the HCC in Japan be mostly related to hepatitis C virus infection.