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991.
992.
993.
Masashi Takano Yoshihiro Kikuchi Takayoshi Asakawa Tomoko Goto Tsunekazu Kita Kazuya Kudoh Junzo Kigawa Noriaki Sakuragi Masaru Sakamoto Toru Sugiyama Nobuo Yaegashi Hiroshi Tsuda Hiroshi Seto Mieko Shiwa 《Journal of cancer research and clinical oncology》2010,136(3):475-481
Objectives
Screening method of endometrial cancer (EC) has not been established yet. Our study was to explore serum biomarkers of EC patients using surface-enhanced laser desorption and ionization-time-of-flight mass spectrometry (SELDI-TOF MS).Methods
Serum samples from 65 EC patients and 40 controls were analyzed by SELDI-TOF MS (training set). Single- and multi-variant analyses were performed to compare protein profiles in serum of EC patients and healthy controls. Subsequently, blind test set including 40 EC patients and 40 controls were analyzed for validation.Results
A panel of four biomarker candidates were selected in training set analysis. These markers could also distinguish stage I patients from controls. Among them, two biomarkers were purified and identified as apolipoprotein A1 and a modified form of apolipoprotein C1. Screening for blind test set using dual-biomarker analysis yielded a sensitivity of 82% and a specificity of 86%.Conclusions
Involvement of apolipoproteins with EC is first suggested in this study. In addition to possibility of screening method for EC, findings of these new biomarkers might be related with carcinogenesis or predisposition to EC. 相似文献994.
995.
Tadashi Wada Mitsuru Abe Nobuhito Yagi Nobuaki Kokubu Yoichiro Kasahara Yu Kataoka Yoritaka Otsuka Yoichi Goto Hiroshi Nonogi 《Heart and vessels》2010,25(3):263-266
Coronary vasospasm can be induced by allergic reactions with some chemical mediators, and the angina and myocardial infarction
secondary to allergy-induced coronary vasospasm are referred to as “Kounis syndrome.” Only two cases of Kounis syndrome following
food ingestion have been reported. However, they had pre-existing atheromatous coronary artery disease, and no provocation
test to induce coronary vasospasm was done. We describe here another probable case of allergic vasospasm after food intake.
To the best of our knowledge, this is the first documented report of a patient with food-induced allergic vasospasm subsequent
to the provocation test with ergometrine maleate. 相似文献
996.
Method of simultaneous stir bar sorptive extraction of phenethylamines and THC metabolite from urine
Stir bar sorptive extraction is a technique used for extracting target substances from various aqueous matrixes such as environmental water, food, and biological samples. This type of extraction is carried out by rotating a coated stir bar is rotated in the sample solution. In particular, Twister bar is a commercial stir bar that is coated with polydimethylsiloxane (PDMS) and used to perform sorptive extraction. In this study, we developed a method for simultaneous detection of amphetamine, methamphetamine, 3,4-methylenedioxyamphetamine, 3,4-methylenedioxymethamphetamine, and a Δ(9)-tetrahydrocannabiniol (THC) metabolite in human urine. For extracting the target analytes, the Twister bar was simply stirred in the sample in the presence of a derivatizing agent. Using this technique, phenethylamines and the acidic THC metabolite can be simultaneously extracted from human urine. This method also enables the extraction of trace amounts of these substances with good reproducibility and high selectivity. The proposed method offers many advantages over other extraction-based approaches and is therefore well suited for screening psychoactive substances in urine specimens. 相似文献
997.
Masashi Kato Mayuko Y. Kumasaka Kozue Takeda Khaled HossainMachiko Iida Ichiro Yajima Yuji Goto Nobutaka Ohgami 《Toxicology in vitro》2011,25(3):623-629
Previous studies have shown that activities of tyrosine kinases and secretion of the active form of matrix metalloproteinase-2 (MMP-2) are correlated with promotion of tumor growth, while apoptotic cell death in cancer cells is correlated with anti-cancer effects. Although arsenic has been reported to have both cancer-promoting and anti-cancer effects, the mechanisms of the arsenic-mediated bidirectional effects remain unknown. We examined the effects of arsenic on both proto-oncogene c-RET-transfected NIH3T3 cells with benign characters and oncogenic RET-MEN2A-transfected NIH3T3 cells with malignant characters. Arsenic promoted not only c-RET tyrosine kinase activity but also genetically activated RET-MEN2A kinase activity with promotion of dimer formation of RET proteins. Arsenic also increased secretion of the active form of MMP-2 in both RET-MEN2A-transfectants and c-RET-transfectants. On the other hand, arsenic promoted poly-(ADP-ribose) polymerase (PARP) degradation and cell death in both malignant and non-malignant cells. Interestingly, l-cysteine inhibited the arsenic-mediated tumor-promoting effects (activation of kinases and MMP-2 secretion) but not arsenic-mediated anti-cancer effects (PARP degradation and cell death). Our results suggest redox-linked regulation of arsenic-mediated activities of kinases and MMP-2 secretion but not arsenic-mediated cell death. Our results also suggest that l-cysteine is an ideal supplement that inhibits arsenic-mediated tumor-promoting effects without affecting arsenic-mediated anti-cancer effects. 相似文献
998.
Yukihara M Ito K Tanoue O Goto K Matsushita T Matsumoto Y Masuda M Kimura S Ueoka R 《Biological & pharmaceutical bulletin》2011,34(5):712-716
It is known that gentamicin (GM) could be a possible treatment for Duchenne Muscular Dystrophy (DMD). However, GM therapy has been hindered by several problems such as severe side effects of GM. In order to resolve these problems, we developed the drug delivery system (DDS) of GM using hybrid liposomes (HL) composed of L-α-dimyristoylphosphatidylcholine (DMPC) and polyoxyethylene(23) lauryl ether (C??(EO)??). The hydrodynamic diameters of HL including GM (GM-HL) were 60-90 nm with a narrow range of the size distribution and the sizes were kept almost constant for over 4 weeks, suggesting that GM-HL could avoid the reticuloendothelial system in vivo. Furthermore, GM-HL accumulated more to the skeletal muscle cells of X chromosome-linked muscular distrophy (mdx) mice as compared to those of normal mice. Significantly, we succeeded in increasing dystrophin positive fibers in skeletal muscle cells of mdx mice using GM-HL along with the reduction of ototoxicity. It is suggested that GM should be carried more efficiently into the muscular cells of mdx mice by HL. These results indicate that HL could be an effective carrier in the DDS of GM therapy for DMD. 相似文献
999.
M Iwama Y Kondo K Shimokado N Maruyama A Ishigami 《Biological & pharmaceutical bulletin》2012,35(8):1367-1370
Here we quantified the uric acid (UA) levels in 11 tissues and plasma of C57BL/6 male mice to track its turnover during 3 to 30 months of aging. UA levels in the adrenal glands, heart, and spleen increased with aging until 30 months of age. Similarly, UA levels in the liver, kidneys, pancreas, and testes increased until the mice were 24 months old. UA levels also rose in the lungs and skeletal muscles from 3 to 6 months and 6 to 12 months, respectively, and then remained at almost the same levels until 30 months of age. In the skin, UA decreased from 3 to 6 months and then stayed nearly constant until 30 months of age. Moreover, the small intestines and plasma had quite stable UA levels during aging. Thus, our assessment of 11 tissue types from mice showed that the UA levels increased in most tissues during aging. 相似文献
1000.
Fujita J Mizuki M Otsuka M Ezoe S Tanaka H Satoh Y Fukushima K Tokunaga M Matsumura I Kanakura Y 《Immunology letters》2011,136(1):61-73
Dendritic cells (DCs) play important roles in tumor immunology. Leukemic cells in patients with myeloid neoplasms can differentiate into DCs in vivo (referred to as in vivo leukemic DCs), which are postulated to affect anti-leukemia immune responses. We established a reproducible culture system of in vitro FLT3 ligand-mediated DC (FL-DC) differentiation from murine lineage(-) Sca-1(+) c-Kit(high) cells (LSKs), which made it possible to analyse the effects of target genes on steady-state DC differentiation from hematopoietic stem/progenitor cells. Using this system, we analysed the effects of various myeloid neoplasm-related gene abnormalities, termed class I and class II mutations, on FL-DC differentiation from LSKs. All class II mutations uniformly impaired FL-DC differentiation maintaining a plasmacytoid DC (pDC)/conventional DC (cDC) ratio comparable to the control cells. In contrast, class I mutations differentially affected FL-DC differentiation from LSKs. FLT3-ITD and a constitutively active form of Ras (CA-N-Ras) yielded more FL-DCs than the control, whereas the other class I mutations tested yielded less FL-DCs. Both FLT3-ITD and FLT3-tyrosine kinase domain (TKD) mutation showed a comparable pDC/cDC ratio as the control. CA-N-Ras, c-Kit-TKD, TEL/PDGFRβ, and FIP1L1/PDGFRα showed a severe decrease in the pDC/cDC ratio. CA-STAT5 and CA-MEK1 severely inhibited pDC differentiation. FLT3-ITD, CA-N-Ras, and TEL/PDGFRβ aberrantly induced programmed death ligand-1 (PD-L1)-expressing DCs. In conclusion, we have established a simple, efficient, and reproducible in vitro FL-DC differentiation system from LSKs. This system could uncover novel findings on how myeloid neoplasm-related gene abnormalities differentially affect FL-DC differentiation from murine hematopoietic stem/progenitor cells in a gene-specific manner. 相似文献