One-pot conversion of trimethylsilyl ethers into urethanes using chlorosulfonyl isocyanate: Application to the synthesis of a novel neuromodulator carisbamate

This paper reports a novel synthetic method for the preparation of various urethanes and the application to the synthesis of carisbamate. The reaction of primary (2a, 2e and 2f) or secondary (2g–2i) trimethylsilyl ethers with chlorosulfonyl isocyanate afforded the corresponding urethanes in good yields without affecting the olefin moiety. However, in the case of secondary benzylic trimethylsilyl ether 2j, the corresponding urethane 3j was obtained in low yield. From the difference in reactivity between the primary and secondary benzylic trimethylsilyl ethers, the one-pot synthesis of carisbamate 1 from bis-trimethylsilyl ether 2l was achieved.     

Mutation and Methylation Analysis of the Chromodomain-Helicase-DNA Binding 5 Gene in Ovarian Cancer

Chromodomain, helicase, DNA binding 5 (CHD5) is a member of a subclass of the chromatin remodeling Swi/Snf proteins and has recently been proposed as a tumor suppressor in a diverse range of human cancers. We analyzed all 41 coding exons of CHD5 for somatic mutations in 123 primary ovarian cancers as well as 60 primary breast cancers using high-resolution melt analysis. We also examined methylation of the CHD5 promoter in 48 ovarian cancer samples by methylation-specific single-stranded conformation polymorphism and bisulfite sequencing. In contrast to previous studies, no mutations were identified in the breast cancers, but somatic heterozygous missense mutations were identified in 3 of 123 ovarian cancers. We identified promoter methylation in 3 of 45 samples with normal CHD5 and in 2 of 3 samples with CHD5 mutation, suggesting these tumors may have biallelic inactivation of CHD5. Hemizygous copy number loss at CHD5 occurred in 6 of 85 samples as assessed by single nucleotide polymorphism array. Tumors with CHD5 mutation or methylation were more likely to have mutation of KRAS or BRAF (P = .04). The aggregate frequency of CHD5 haploinsufficiency or inactivation is 16.2% in ovarian cancer. Thus, CHD5 may play a role as a tumor suppressor gene in ovarian cancer; however, it is likely that there is another target of the frequent copy number neutral loss of heterozygosity observed at 1p36.     

Changes of isoagglutinin titres after ABO-incompatible allogeneic stem cell transplantation

We investigated the changes in isoagglutinin titres in 62 patients who underwent ABO-incompatible allogeneic stem cell transplantation. After major [and/or (+/-) minor] ABO-incompatible transplantation, recipient-derived isoagglutinins against donor-type red blood cells (RBCs) disappeared more rapidly in unrelated recipients (P = 0.006) and in patients with acute graft-versus-host disease (GVHD, P = 0.025) than in sibling recipients and in patients without acute GVHD respectively. Pure red cell aplasia (PRCA) developed in 10 out of 35 evaluable patients who underwent major (+/- minor) ABO-incompatible transplantation, and the post-transplant increase of isoagglutinin titres was a significant predictor for the occurrence of PRCA. In five out of 36 patients who underwent minor (and/or (+/-) major) ABO-incompatible transplantation, donor-derived isoagglutinins against recipient RBCs were detectable without clinically overt haemolysis. Isoagglutinin titres against ABO antigens absent both on recipient and donor RBCs decreased during the early post-transplant period then rose subsequently in 24 out of 29 patients at (median) d 59 post transplant. Our study showed that changes in isoagglutinin titres might have clinical implications in the occurrence of immunohaematological complications such as PRCA or immune-mediated haemolysis, and might reflect immunohaematological reconstitution after transplantation. Furthermore, our data regarding time to disappearance of recipient-derived isoagglutinins against donor-type RBCs after major ABO-incompatible transplantation suggest the presence of a graft-versus-plasma cell effect.     

Contrast-enhanced power Doppler US: is it useful in the differentiation of gallbladder disease?

Thirteen patients with gallbladder disease underwent power Doppler ultrasound (PDUS) before and after microbubble contrast agent injection. Lesion and liver bed vascularity was evaluated. Pathological diagnoses in nine patients were two acute cholecystitis, four chronic inflammation, one adenoma and two adenocarcinoma. Two cases of cancer were included on clinical and radiological findings. Two cases were excluded because no pathologic diagnosis was available. Liver bed hyperemia was noted only in acute cholecystitis. Contrast-enhanced PDUS was superior to nonenhanced PDUS in the demonstration of vascularity of gallbladder diseases. However, contrast-enhanced PDUS has limited value in the differentiation.     

PLENARY LECTURES-PL1 Toxicity of perfluorooctane sulfonate and perfluorooctanoate

Persistent perfluorinated organic compounds, such as perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) are used in a variety of industrial applications. They are very stable in the environment, distribute widely in the global environment and in wild life, and are detected in human sera.     

Bioactive asterosaponins from the starfish Culcita novaeguineae

Two new sulfated steroidal pentaglycosides（asterosaponins）,novaeguinosides Ⅰ（2） and （Ⅱ）2,along with the known regularoside B（1）were isolated from the starfish Culcita novaeguineae.Their structures were elucidated by extensive NMR techniques as well as chemical evidence.     

Cysteine 230 modulates tumor necrosis factor-related apoptosis-inducing ligand activity

Biologically active tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) protein is known to form a homotrimer in solution. Unexpectedly, the recombinant active human TRAIL protein purified from bacteria produced two bands (a Mr 21,000 monomer derived from the disruption of the trimer in SDS gels and a Mr 42,000 dimer) on nonreducing SDS gels. The treatment of this TRAIL protein with DTT, a reducing agent, abolished formation of the Mr 42,000 band, suggesting that the Mr 42,000 band was the result of intermolecular disulfide bridge formation. Inspection of the amino acid sequence of human TRAIL protein identified a unique cysteine residue at position 230, and subsequent site-directed mutagenesis revealed that this amino acid residue is responsible for the appearance of the Mr 42,000 dimer. The binding analysis using the TRAIL protein and a TRAIL receptor (death receptor 5) revealed that both the dimer and the trimer bind to death receptor 5 with similar affinity. Interestingly, mutation of cysteine 230 to glycine completely abolished the apoptotic activity of TRAIL protein. The disruption of the dimer in the mixture of TRAIL dimer and trimer increased the apoptotic activity slightly, suggesting that the dimer has less apoptotic activity than the trimer. Therefore, our data indicate that cysteine 230 is not only required for TRAIL function but also modulates the apoptotic activity of TRAIL by forming an intermolecular disulfide bridge.     

Effect of a novel vitamin D3 analog, EB1089, on G1 cell cycle regulatory proteins in HL-60 cells

Progression of cell cycle in eukaryotes is regulated by a series of the cyclin-dependent kinases (CDKs) and cyclin-dependent kinase inhibitors (CDKIs). It has been shown that 1,25(OH)2D3 is able to arrest cell cycle at G1 phase in malignant cells including HL-60 cells. EB1089 is a novel 1,25(OH)2D3 analog that has more potent antileukemic properties with reduced hypercalcemic effect in vitro and in vivo than 1,25(OH)2D3. In the present study, we examined the effect of EB1089 on HL-60 cells at the protein levels of several G1 regulatory proteins. Exposure of HL-60 cells to EB1089 (1x10-8 M) for 3 days showed the G1 block by FACS analysis. The level of p21 was markedly induced in HL-60 cells treated with EB1089 at 24 h, and p27 were progressively increased in a time-dependent manner. The expressions of CDK2 and CDK6 were down-regulated during G1 block of HL-60 cells, and CDK4 is progressively elevated. In addition, level of cyclin D1 was increased in a time-dependent manner, however, no change of cyclin E was noted through the G1 to S traverse. Immunoprecipitation study demonstrated that p27 did not bind to CDK2, CDK4 and CDK6 in EB1089-treated HL-60 cell extracts. In contrast, complexes immunoprecipitated from EB1089-treated HL-60 cells with antibodies CDK2 and CDK6 contained higher amounts of immunodetectable p21 protein compared to untreated HL-60 cells, whereas no detectable change was noted with anti-CDK4 antibody. Furthermore, the kinase activities of CDK2 and CDK6 were decreased while little change was observed in CDK4 activity. These data indicated that p21 protein is a strong candidate for the control of G1 progression in EB1089-treated HL-60 cells, and its major target molecules are CDK2 and CDK6.     

Antitumor components ofAgrocybe cylindracea

To find pharmacologically active components ofAgrocybe cylindracea, its basidiocarps were extracted with water. The extracts were separated by DEAE cellulose column chromatography, Sepharose CL-4B gel filtration, and Concanavalin A-Sepharose 4B affinity chromatography. Among the obtained fractions fromA. cylindracea, fraction IN which was the neutral proteinbound-polysaccharide fraction exhibited a marked antitumor activity and it was tentatively named “Cylindan”. It showed about 70% of tumor inhibition against the solid form of sarcoma 180 when a dose of 30 mg/kg/day was intraperitoneally injected into ICR mice. When each fraction was examined by chemical analysis, Cylindan consisted of 85% polysaccharide, 3% protein and 1% hexosamine. Its polysaccharide moiety contained glucose, mannose, fucose and galactose and its protein moiety contained the comparatively large amounts of aspartic acid and glycine, and other 11 amino acids.     

间硝苯地平对血管紧张素Ⅱ促进血管平滑肌细胞增殖和蛋白质合成的影响

以培养血管平滑肌细胞(vascularsmcothmusclecell,VSMC)为模型,观察了间硝苯地平(m-nifedipine,m-Nif)对血管紧张素Ⅱ(angiotensinⅡ,ANGⅡ)促进VSMC增殖和蛋白质合成的影响。结果表明,m-Nif抑制ANGⅡ(100nmol·L^-1)引起VSMC[³H]thymidine和[³H]leucine参入,并呈剂量依赖性。m-Nif(2×10^-6mol·L^-1)可抑制ANGⅡ对VSMC的刺激、DNA及蛋白质合成速率,分别降低了46%,58%,53%。提示m-Nif可抑制ANGⅡ对VSMC增殖和蛋白合成的促进作用。