109 research outputs found
Northcott numbers for the weighted Weil heights
We answer the question of Vidaux and Videla about the distribution of the
Northcott numbers for the Weil height. We solve the same problem for the
weighted Weil heights. These heights generalize both the absolute and relative
Weil height. Our results also refine those of Pazuki, Technau, and Widmer.Comment: 16 page
Northcott numbers for generalized weighted Weil heights
We give a generalization of weighted Weil heights. These heights generalize
both Weil's heights and Dobrowolski's height. We study Northcott numbers for
our heights. Our results generalize the authors' former work on Vidaux and
Videla's question about the Northcott number. As an application, we evaluate
Northcott numbers for Talamanca's spectral height on matrices.Comment: 28 page
Cellular Responses of Human Lymphatic Endothelial Cells to Carbon Nanomaterials
One of the greatest challenges to overcome in the pursuit of the medical application of carbon nanomaterials (CNMs) is safety. Particularly, when considering the use of CNMs in drug delivery systems (DDSs), evaluation of safety at the accumulation site is an essential step. In this study, we evaluated the toxicity of carbon nanohorns (CNHs), which are potential DDSs, using human lymph node endothelial cells that have been reported to accumulate CNMs, as a comparison to fibrous, multi-walled carbon nanotubes (MWCNTs) and particulate carbon black (CB). The effect of different surface characteristics was also evaluated using two types of CNHs (untreated and oxidized). In the fibrous MWCNT, cell growth suppression, as well as expression of inflammatory cytokine genes was observed, as in previous reports. In contrast, no significant toxicity was observed for particulate CB and CNHs, which was different from the report of CB cytotoxicity in vascular endothelial cells. These results show that (1) lymph endothelial cells need to be tested separately from other endothelial cells for safety evaluation of nanomaterials, and (2) the potential of CNHs as DDSs.ArticleNANOMATERIALS. 10(7):1374 (2020)journal articl
Lipase-catalyzed domino Michael-aldol reaction of 2-methyl-1,3-cycloalkanedione and methyl vinyl ketone for the synthesis of bicyclic compounds
Synthesis of bicyclic compounds was achieved via a lipase-catalyzed, stereoselective, domino Michael–aldol reaction of 2-methyl-1,3-cycloalkanedione and methyl vinyl ketone. Appropriate reaction conditions, including the type of enzyme, solvent, and temperature, were determined. In addition, the effects of solvent polarity and addtives were investigated. The reaction proceeded in the presence of lipase AS in a solution of 20% acetone in dimethylsulfoxide (DMSO) at 10 °C for 8 days, followed by the addition of p-toluenesulfonic acid (TsOH) to afford bicyclic compounds in 51–83% yields with moderate stereoselectivity. Although this domino Michael–aldol reaction showed only moderate stereoselectivity, even with the acid-supported enhancement of the reaction, these results represent potential new applications for lipase
Antitumor effect of WEE1 blockade as monotherapy or in combination with cisplatin in urothelial cancer
Overcoming cisplatin (CDDP) resistance is a major issue in urothelial cancer (UC), in which CDDP-based chemotherapy is the first-line treatment. WEE1, a G2/M checkpoint kinase, confers chemoresistance in response to genotoxic agents. However, the efficacy of WEE1 blockade in UC has not been reported. MK-1775, a WEE1 inhibitor also known as AZD-1775, blocked proliferation of UC cell lines in a dose-dependent manner irrespective of TP53 status. MK-1775 synergized with CDDP to block proliferation, inducing apoptosis and mitotic catastrophe in TP53-mutant UC cells but not in TP53-WT cells. Knocking down TP53 in TP53-WT cells induced synergism of MK-1775 and CDDP. In UMUC3 cell xenografts and two patient-derived xenograft lines with MDM2 overexpression, in which the p53/cell cycle pathway was inactivated, AZD-1775 combined with CDDP suppressed tumor growth inducing both M-phase entry and apoptosis, whereas AZD-1775 alone was as effective as the combination in RT4 cell xenografts. Drug susceptibility assay using an ex vivo cancer tissue-originated spheroid system showed correlations with the in vivo efficacy of AZD-1775 alone or combined with CDDP. We determined the feasibility of the drug susceptibility assay using spheroids established from UC surgical specimens obtained by transurethral resection. In conclusion, WEE1 is a promising therapeutic target in the treatment of UC, and a highly specific small molecule inhibitor is currently in early phase clinical trials for cancer. Differential antitumor efficacy of WEE1 blockade alone or combined with CDDP could exist according to p53/cell cycle pathway activity, which might be predictable using an ex vivo 3D primary culture system
Gallbladder Metastasis from Renal Cell Carcinoma
A 73-year-old female was operated with radical nephrectomy and cholecystectomy for renal cell carcinoma and suspected gallstones after 9 courses of sunitinib treatment. Gallbladder specimen showed gallbladder metastasis originating from the renal cell carcinoma. Gallbladder metastasis from renal cell carcinoma is rare. Here, we discuss a case of gallbladder metastasis from renal cell carcinoma
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