Summary Membrane cofactor protein (MCP, CD46) is one of the complement regulatory proteins, and is widely distributed in human organs and protects cells from complement-mediated cytotoxicity. We analysed the distribution and the intensities of MCP in liver diseases and evaluated the role of MCP during hepatocarcinogenesis. Western blot analysis revealed that relative densities (density of the sample/density of the standard sample) of MCP in 27 HCC, 18 liver cirrhosis, nine chronic hepatitis and 12 normal liver were 0.63 ± 0.23, 0.21 ± 0.07, 0.25 ± 0.10 and 0.11 ± 0.03 (mean ± s.d.) respectively. MCP expression in hepatocellular carcinoma (HCC) was significantly higher than that in both liver cirrhosis and chronic hepatitis (P < 0.01). The difference in the tumour sizes, the grades of differentiation and viral marker status did not affect the expression. Immunohistological analysis revealed that MCP was distributed mainly in the basolateral membrane of the hepatic cord in non-cancerous liver, along with endothelial cells and bile duct cells. In HCC, the protein was observed on the membrane in a non-polarized fashion. These data suggest that HCC cells acquire the increased MCP expression in a development of HCC and may escape from tumour-specific complement-mediated cytotoxicity.

An incremental positivity of telomerase was observed during hepatocarcinogenesis. The use of this assay in 21-G-needle biopsy specimens may be useful in clinical examination.

[reaction: see text]. We have completed the total synthesis of natural (+)-tubelactomicin A (1), a 16-membered macrolide antibiotic. This Letter presents a highly efficient synthesis of the upper-half segment (C14-C24) and the completion of the total synthesis featuring a high-yielding Stille coupling for the connection of the upper-half and lower-half segments and Mukaiyama macrolactonization for the construction of the entire structure of 1.

HARUSHIGE NAKATSUKASA, KOUZOU ASHIDA, TOSHIHIRO HIGASHI, SOUHEI OHGUCHI, SO TSUBOI, NAOKI HINO, KAZUHIRO NOUSO, YOSHIAKI URABE, NOBUYUKI KINUGASA, KEIGO YOSHIDA, SHUJI UEMATSU, MASAHIKO ISHIZAKI, YOSHIYUKI KOBAYASHI, AND TAKAO TSUJI Hepatocellular carcinoma (HCC) is one of the most prevaThe cellular distribution of tissue inhibitor of melent malignancies in Japan and China, and frequently occurs talloproteinases (TIMP)-1, and TIMP-2 was studied by in hepatitis B or C virus-related chronic hepatitis or cirrhousing in situ hybridization in surgically removed husis. In particular, cirrhosis has been regarded as a high-risk man hepatocellular carcinomas (HCCs) and cholandisease state for developing HCCs. A unique feature of HCC giocellular carcinomas (CCCs). The purpose of this development is the occurrence of the tumor in fibrotic or cirstudy was to characterize the potential involvement rhotic liver that contains abundant extracellular matrices of TIMPs in the development of HCCs and CCCs. All (ECMs). Therefore, the capacity of HCC to degrade the surHCCs and CCCs expressed TIMPs. The distribution rounding ECMs may be an important trait for growth, invaof transcripts for TIMPs in the tumors was mostly sion, and metastasis. homogeneous. Expression of TIMPs in cancer cellsThe characteristic features of malignant tumors are the was more intense than that in the surrounding noninvasion to cross tissue boundaries and the metastasis to cancerous liver (either, cirrhosis, chronic hepatitis, distant organs. Many steps that occur during cancer invasion or normal), and expression of TIMP-1 was stronger and metastasis require specific interactions between maligthan that of TIMP-2. Expression of TIMPs varied nant cells and the ECMs, 1 particularly in regard to HCC and among HCC nodules, but there was no obvious associcirrhotic liver. Multiple humoral factors are involved in this ation between the expression level of TIMPs and difprocess: matrix metalloproteinases (MMPs), tissue inhibitor ferentiation stages or invasiveness of the HCCs. Tranof metalloproteinases (TIMPs), and various cytokines. An imscripts for TIMPs were clearly demonstrated in the balance between TIMPs and MMPs may be an important metastatic HCC nodules in the lung. Expression of factor in tumor invasion and metastasis. TIMP-1 in CCC was strong, and small nodules of CCC Three members of the TIMP family have been described. 2 were recognized in the liver. ImmunohistochemicalEach TIMP is the product of a separate gene. TIMP-1 is a 28-study for TIMP-1 revealed a consistent staining of the kd glycoprotein, whereas TIMP-2 is a 21-kd nonglycosylated TIMP-1 protein with the transcripts. In the perituprotein. Between TIMP-1 and TIMP-2, there is 37% amino moral histologically normal liver, which was not inacid identity and 65.6% overall homology. 3 TIMP-3 has been fected with either hepatitis B or C virus, expression identified as a 21-kd protein and shares an amino acid seof TIMP-1 was found in various cell types, but that of quence homology of 40% with TIMP-1 and 45%...

AcknowledgmentsThe authors are grateful to Yoshimitsu Kawai, Makoto Sumikawa, and Ena Dejima of Ritsumeikan University for their assistance in data collection. The authors would also like to thank Tsukinowa Driving School for allowing us to use their driving course. In the centrifugal head-tilt condition, participants intentionally tilted their heads towards the centrifugal force, whereas in the centripetal head-tilt condition, the participants tilted their heads against the centrifugal acceleration. The eyes-open and eyes-closed cases were investigated for each head-tilt condition. In the experimental runs, the sickness rating in the centripetal head-tilt condition was significantly lower than that in the centrifugal head-tilt condition. Moreover, the sickness rating in the eyes-open condition was significantly lower than that in the eyes-closed condition. The results suggest that an active head-tilt motion against the centrifugal acceleration reduces the severity of motion sickness both in the eyes-open and eyes-closed conditions. They also demonstrate that the eyes-open condition significantly reduces the motion sickness even when the head-tilt strategy is used. 3