Dynamic MRI is useful for distinguishing high-flow from low-flow vascular malformations, especially when the contrast rise time of the lesion is measured.

High-refractive-index polymers (HRIPs) are currently in demand for the fabrication of state-of-the-art optical devices with high performance. However, few HRIPs that display both ultrahigh refractive index (over 1.8) and high Abbe number (over 20) have been reported owing to the typical trade-off between these two parameters. Herein, we found that poly(2hydroxy-1,4-phenylene sulfide) exhibited an unprecedented ultrahigh refractive index (n D = 1.80) with an amorphous nature, high glass-transition temperature, good transparency, and high Abbe number (ν D = 20). Spectroscopic analyses and density measurements revealed that the dense hydrogen-bond (H-bond) networks of the hydroxy-substituted poly(phenylene sulfide) in the bulk state enabled the realization of an ultrahigh refractive index without any decline in transparency.

Abstract. The major cause of death in colorectal cancer is related to liver metastasis. Although the metastatic process has been well studied, many aspects of the molecular genetic basis of metastasis remain unclear. Elucidation of the molecular nature of liver metastasis is urgent to improve the outcome of colorectal cancer. We analyzed the chronological gene expression profiles of 104 colorectal samples corresponding to oncogenic development including normal mucosa, localized and metastasized primary tumors, and liver metastatic lesions as fundamental samples using a custom cDNA microarray. The gene expression patterns in 104 samples were classified into four groups closely associated with their metastatic status, and the genes of each group appropriately reflected the metastatic process. To investigate the existence of metastatic potential in primary tumors using metastasis-related genes detected by chronological analysis, we performed a hierarchical cluster and supervised classification analysis of 28 independent primary tumors. Hierarchical cluster analysis segregated the tumors according to their final metastatic status, rather than their clinical stages, and the profile of metastasized primary tumors resembled one of a metastatic lesion apart from a primary lesion rather than one of a non-metastasized primary tumor. Using the supervised classification approach, the expression profile of these genes allowed the classification of tumors diagnosed as localized cancer into two classes, the localized and the metastasized class, according to their final metastatic status. The disease-free survival and overall survival were significantly longer in the localized class than the metastasized class. Chronological analysis of the gene expression profile provides a better understanding of the metastatic process. Our results suggest that the metastatic potential is already encoded in the primary tumor and is detectable by a gene expression profile, which allows the prediction of liver metastasis in patients diagnosed with localized tumors and also the design of new strategies for the treatment and diagnosis of colorectal cancer.

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We found that mannitol-1-phosphate dehydrogenase (MtlD), a component of the mannitol-specific phosphotransferase system, is required for glucitol assimilation in addition to GutR, GutB, and GutP in Bacillus subtilis. Northern hybridization of total RNA and microarray studies of RNA from cells cultured on glucose, mannitol, and glucitol indicated that mannitol as the sole carbon source induced hyperexpression of the mtl operon, whereas glucitol induced both mtl and gut operons. The B. subtilis mtl operon consists of mtlA (encoding enzyme IICBA mt1 ) and mtlD, and its transcriptional regulator gene, mtlR, is located 14.4 kb downstream from the mtl operon on the chromosome. The mtlA, mtlD, and mtlR mutants disrupted by the introduction of the pMUTin derivatives MTLAd, MTLDd, and MTLRd, respectively, could not grow normally on either mannitol or glucitol. However, the growth of MTLAd on glucitol was enhanced by IPTG (isopropyl-␤-D-thiogalactopyranoside). This mutant has an IPTG-inducible promoter (Pspac promoter) located in mtlA, and this site corresponds to the upstream region of mtlD. Insertion mutants of mtlD harboring the chloramphenicol resistance gene also could not grow on either mannitol or glucitol. In contrast, an insertion mutant of mtlA could grow on glucitol but not on mannitol in the presence or absence of IPTG. MtlR bound to the promoter region of the mtl operon but not to a DNA fragment containing the gut promoter region.Bacteria express many phosphoenolpyruvate-dependent phosphotransferase systems (PTS) consisting of sugar-specific transport proteins and phosphorylation mechanisms to utilize various sugars. The PTS are primarily specific to each sugar, but they can transport other sugars to a lesser extent (4). Furthermore, their substrate specificity can be changed by the amino acid replacement(s) (1, 2). Genome sequence analysis of Bacillus subtilis (15) has identified 21 complete PTS, 17 of which were characterized or estimated via the corresponding sugars (21; see also the B. subtilis genetic databases BSORF [http://bacillus.genome.ad.jp/] and SubtiList [http://genolist .pasteur.fr/SubtiList/]). The operon for the mannitol-specific PTS is located at 38.5°of the B. subtilis chromosome. Mannitol-specific PTS have been investigated in Escherichia coli (16), in Bacillus stearothermophilus (8), and in other organisms (3, 10). The mtl operon in E. coli consists of the mtlA, mtlR, and mtlD genes that encode the mannitol transporter (enzyme IIC-BA mtl ), a transcriptional regulator, and mannitol-1-phosphate dehydrogenase, respectively, and that in B. stearothermophilus comprises four genes: mtlA (enzyme IICB mtl ), mtlR, mtlF (enzyme IIA mtl ), and mtlD. In contrast, the B. subtilis mtl operon consists of only the mtlA (enzyme IICBA mtl ) and mtlD genes, and the operon does not contain a gene for a transcriptional regulator. However, the gene ydaA, which was recently renamed mtlR and which is homologous to the mtlR genes of E. coli and B. stearothermophilus, is located 14.4 kb down stream from the mtl o...