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A flexible cylindrical cryptand (1b) with two m-phenylene-26-crown-8 ethers has been prepared, and its complexing properties with respect to tetravalent cationic bis-paraquat guests have been investigated. Diffusion-ordered spectroscopy nuclear magnetic resonance (NMR) and titration experiments using cold electrospray ionization mass spectrometry and 1H NMR revealed that 1bhas versatile complexing properties with respect to tetravalent cationic guests used despite the guest molecules’ length and shape.

The first total synthesis of vineomycin A1(1) has been accomplished. Structure–activity relationship studies for cytotoxicity against human breast cancer MCF-7 cells using several synthetic vineomycin A1analogues differing in the number and position of glycon moieties revealed that the cytotoxicity increased as the number of glycon moieties increased. The position of the glycon moiety was one of the key factors for the cytotoxicity of 1. Moreover, in vitro analysis of the cytotoxicity of 1against MCF-7 cells indicated for the first time that 1effectively induced cancer cell death by apoptosis, not by acting as a DNA intercalating agent.

In salivary gland pleomorphic adenoma, expression of extracellular matrix (ECM) substances indicates that tumor epithelial cells are becoming chondrogenic and will produce cartilage-like mesenchymal tissues. Sox9, the master transcription factor of chondrogenesis, is expressed in mouse salivary gland cells. To clarify the mechanism behind chondrogenesis in tumor epithelial cells, we examined the expression of transcription factors related to chondrogenesis in tumors and salivary glands. Reverse transcriptase-polymerase chain reaction (RT-PCR), quantitative real-time RT-PCR, and immunostaining were performed on pleomorphic adenoma tissues, salivary gland tissues, and human submandibular gland (HSG) cells. The mRNAs of essential transcription factors for chondrogenesis—Sox9, Sox6, and Sox5—were detected in both tumor and salivary gland tissues. The mRNAs of aggrecan and type II collagen—cartilage-specific ECM substances—were detected only in tumors. Sox9 and Sox6 proteins were colocalized in many epithelial cells in tumors and salivary glands. Tumor epithelial cells also possessed aggrecan protein and occasionally type II collagen protein. Moreover, mRNAs for transcription repressors of chondrogenesis δEF1and AP-2αwere detected in both tumors and salivary glands, whereas Twist1 mRNA was detected only in salivary glands and was at significantly low-to-undetectable levels in tumors. Twist1 protein was localized in the Sox9-expressing salivary gland cells. HSG cells expressed Sox9, Sox6, and Twist1, but not aggrecan or type II collagen, and thus were similar to salivary gland cells. Twist1 depletion by Twist1 siRNA led to the upregulation of aggrecan and type II collagen mRNA expression in HSG cells. In contrast, forced expression of Twist1, using Twist1 cDNA, resulted in the downregulation of both these genes. Taken together, these results indicate that salivary gland cells have a potential for chondrogenesis, and Twist1 depletion concomitant with neoplastic transformation, which would permit tumor epithelial cells to produce cartilage-like mesenchymal tissues in salivary gland pleomorphic adenoma.

In salivary gland pleomorphic adenoma, expression of extracellular matrix (ECM) substances indicates that tumor epithelial cells are becoming chondrogenic and will produce cartilage-like mesenchymal tissues. Sox9, the master transcription factor of chondrogenesis, is expressed in mouse salivary gland cells. To clarify the mechanism behind chondrogenesis in tumor epithelial cells, we examined the expression of transcription factors related to chondrogenesis in tumors and salivary glands. Reverse transcriptase-polymerase chain reaction (RT-PCR), quantitative real-time RT-PCR, and immunostaining were performed on pleomorphic adenoma tissues, salivary gland tissues, and human submandibular gland (HSG) cells. The mRNAs of essential transcription factors for chondrogenesis—Sox9, Sox6, and Sox5—were detected in both tumor and salivary gland tissues. The mRNAs of aggrecan and type II collagen—cartilage-specific ECM substances—were detected only in tumors. Sox9 and Sox6 proteins were colocalized in many epithelial cells in tumors and salivary glands. Tumor epithelial cells also possessed aggrecan protein and occasionally type II collagen protein. Moreover, mRNAs for transcription repressors of chondrogenesis δEF1 and AP-2α were detected in both tumors and salivary glands, whereas Twist1 mRNA was detected only in salivary glands and was at significantly low-to-undetectable levels in tumors. Twist1 protein was localized in the Sox9-expressing salivary gland cells. HSG cells expressed Sox9, Sox6, and Twist1, but not aggrecan or type II collagen, and thus were similar to salivary gland cells. Twist1 depletion by Twist1 siRNA led to the upregulation of aggrecan and type II collagen mRNA expression in HSG cells. In contrast, forced expression of Twist1, using Twist1 cDNA, resulted in the downregulation of both these genes. Taken together, these results indicate that salivary gland cells have a potential for chondrogenesis, and Twist1 depletion concomitant with neoplastic transformation, which would permit tumor epithelial cells to produce cartilage-like mesenchymal tissues in salivary gland pleomorphic adenoma.

Leiomyosarcoma of the oral cavity is a very rare tumor type associated with aggressive clinical behavior and a low survival rate. However, this tumor may also be encountered as a slow-growing, non-ulcerated, painless mass in its early stage. We report a case of leiomyosarcoma, affecting the gingival mucosa of a 24-year-old male. The tumor mimicked an epulis, because it was encountered as a slow-growing, discreet, firm, non-ulcerated, painless mass without any evidence of resorption of the maxillary bone.

The cDNA clone of novel cytochrome P450 CYP703A1 from petunia floral buds was isolated by RT-PCR. The nucleotide sequences of this cDNA clone contained the open reading frame that has been predicted to encode polypeptides consisting of 539 amino acid residues. A significantly high level of the transcript of the cyp703A1gene was found in the early stage of petunia flower buds, but not in the leaves, stems and roots. The 1041bp 5′-flanking sequences of the cyp703A1gene contained the conserved motifs of ATHB-1, AGAMOUS, MYB.Ph3, P and SBF-1 binding boxes. CYP703A1 cDNA was expressed in yeast Saccharomyces cerevisiaeAH22 cells under the control of an alcohol dehydrogenaseI promoter and terminator. The recombinant yeast microsome containing the CYP703A1 hemoprotein were found to metabolize lauric acid. Based on these results, CYP703A1 was specifically expressed in the early stage of flower development and appeared to participatie in the monooxygenation of fatty acids.

An asymmetric total synthesis of the 14-membered diene unit, (1S,2S,4E,6E,10S,11Z,14R)-10,14-epoxy-4-isopropenyl-1,7,11-trimethyl-4,6,11-cyclotetradecatriene-1,2-diol (3), of methyl sarcophytoate (1) has been achieved. Methyl ketone, (3S,4S)-3,4-(isopropylidenedioxy)-3,7-dimethyl-6-octen-2-one (6), was enantioselectively prepared from geraniol via Sharpless asymmetric epoxidation and a regioselective epoxide-opening reaction. The aldol coupling between the lithium enolate of 6and aldehyde, (2E,6E)-2,6-dimethyl-8-(2,2-dimethylpropanoyloxy)-2,6-octadienal (7), which was also prepared from geraniol, gave a 1 : 1 separable mixture of the adducts (17and 18). Reduction of the carbonyl group in 17and 18, followed by regioselective oxidation of the allylic hydroxy group, afforded α,β-unsaturated ketone, (2E,6E,10R,11R,12S)-1-(2,2-dimethylpropanoyloxy)-10-hydroxy-11,12-(isopropylidenedioxy)-3,7,11,15-tetramethyl-2,6,14-hexadecatrien-8-one (5). The intramolecular oxy-Michael addition of 5followed by regioselective enol triflation and deoxygenation gave dihydropyran, (2E,6S,7Z,10R,11R,12S)-1-(2,2-dimethylpropanoyloxy)-6,10-epoxy-11,12-(isopropylidenedioxy)-3,7,11,15-tetramethyl-2,7,14-hexadecatriene (31). The regioselective epoxidation of 31and a subsequent functional-group transformation gave (2E,6S,7Z,10R,11R,12S,14RS)-6,10 : 14,15-diepoxy-11,12-(isopropylidenedioxy)-3,7,11,15-tetramethyl-1-(phenylthio)-2,7-hexadecadiene (4). The 14-membered ring formation was achieved by the treatment of 4with the n-BuLi–Bu2Mg complex to give (1Z,3S,6E,8RS,9RS,11S,12R,13R)-3,13-epoxy-9-(1-hydroxy-1-methylethyl)-11,12-(isopropylidenedioxy)-2,6,12-trimethyl-8-(phenylthio)-1,6-cyclotetradecadiene (33), which was transformed to 3through triene construction and deacetonidation.

For clinicians to provide more efficient early mobilization in patients with acute stroke, they must quantitatively evaluate the motion characteristics of the patients. To measure the motion in the acute phase, it is necessary to prevent physical interference between the measurement and medical equipment. This study classified abnormal muscle synergies during sit-to-stand motion in patients with acute stroke by using small, wirelessly operable, noninvasive surface electromyography devices. Four patients with acute stroke and four healthy adults performed a six-directional isometric contraction task and a sit-to-stand motion task. A nonnegative matrix factorization algorithm was applied to the muscle activity data to extract the muscle synergies. Hierarchical cluster analysis was used to classify these synergies. The results suggest that sit-to-stand motion characteristics according to the severity of effects in patients with acute stroke can be quantitatively classified by muscle synergy analysis. The spatial structure of muscle synergies of patients was classified into different clusters from that of the healthy adults. The abnormal muscle synergy in patients with severe paresis is considered severe in that it cannot be modulated according to the task. The muscle synergies in patients with moderate paresis were modulated in the sit-to-stand motion to compensate for extensor muscle weakness. Such abnormal muscle synergy in the sit-to-stand motion is useful as a reference for motion practice, especially for early mobilization after the onset of a stroke. In addition, the results verify that the early to late stages of recovery can be consistently evaluated with this small, wireless noninvasive electromyography device.