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1.
The role of sodium ions in amylase secretion from rat parotid cells was studied using various Na+-free media and monensin. In a sucrose medium, amylase secretion was not stimulated by isoproterenol but was significantly stimulated by dibutyryl cAMP. In choline chloride and LiCl media, both isoproterenol and dibutyryl cAMP clearly evoked amylase release. Monensin itself elicited amylase secretion slightly, but significantly inhibited the secretion stimulated by isoproterenol or dibutyryl cAMP. The inhibitory effect of monensin was detectable even in choline chloride, LiCl and KCl media. These results indicate that sodium ions are not essential for amylase secretion from rat parotid cells and that the inhibitory effect of monensin is independent of influx of sodium ions or efflux of potassium ions. 相似文献
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Tomohiro Asai Takuma Tsuzuku Shoya Takahashi Ayaka Okamoto Takehisa Dewa Mamoru Nango Kenji Hyodo Hiroshi Ishihara Hiroshi Kikuchi Naoto Oku 《Biochemical and biophysical research communications》2014
Lipid nanoparticles (LNP) modified with cell-penetrating peptides (CPP) were prepared for the delivery of small interfering RNA (siRNA) into cells. Lipid derivatives of CPP derived from protamine were newly synthesized and used to prepare CPP-decorated LNP (CPP-LNP). Encapsulation of siRNA into CPP-LNP improved the stability of the siRNA in serum. Fluorescence-labeled siRNA formulated in CPP-LNP was efficiently internalized into B16F10 murine melanoma cells in a time-dependent manner, although that in LNP without CPP was hardly internalized into these cells. In cells transfected with siRNA in CPP-LNP, most of the siRNA was distributed in the cytoplasm of these cells and did not localize in the lysosomes. Analysis of the endocytotic pathway indicated that CPP-LNP were mainly internalized via macropinocytosis and heparan sulfate-mediated endocytosis. CPP-LNP encapsulating siRNA effectively induced RNA interference-mediated silencing of reporter genes in B16F10 cells expressing luciferase and in HT1080 human fibrosarcoma cells expressing enhanced green fluorescent protein. These data suggest that modification of LNP with the protamine-derived CPP was effective to facilitate internalization of siRNA in the cytoplasm and thereby to enhance gene silencing. 相似文献
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Takuma Watanobe Naotaka Ishiguro Naohiko Okumura Masuo Nakano Akira Matsui Hitomi Hongo Hiroshi Ushiro 《Journal of molecular evolution》2001,52(3):281-289
The Kabukai A site (5 to 8C A.D.) of the Okhotsk cultural area is on Rebun Island, a small island near the coast, north–northwest
of Hokkaido, Japan. Specimens of Sus scrofa, called the Sakhalin pig, were discovered in five cultural layers at the Kabukai A site. Ancient DNA was extracted from the
remains of 42 Sakhalin pig bones. Thirty-nine nucleotide sequences of the 574-bp mitochondrial DNA control region, estimated
to have originated from at least 21 individuals, were amplified and analyzed phylogenetically. Nine distinct haplotypes (A1,
A2, A3, B1, B2, C1, C2, D1, and D2) from this site were classified into four haplotype groups (A, B, C, and D) by parsimonious
network analysis. Phylogenetic analysis of 9 ancient and 55 modern haplotypes indicated that the population of Sakhalin pigs
at the Kabukai A site belonged to two distinct clusters; haplotype groups A and B formed a cluster comprised only of themselves,
and haplotype groups C and D belonged to the cluster of one of the two genetic groups of Japanese wild boars uniquely distributed
in the western part of Japan, including one northeast Mongolian wild boar. Analysis of the haplotype distribution among three
archaeological sites and their historical transitions among the five layers reflecting the cultural periods at the Kabukai
A site suggests that the Sakhalin pig populations were introduced from Sakhalin island and the Amur River basin in the northeastern
Eurasian continent together with some cultural influences.
Received: 18 April 2000 / Accepted: 24 November 2000 相似文献
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Noriaki Minakawa Naoshi Kojima Takuma Sasaki Akira Matsuda 《Nucleosides, nucleotides & nucleic acids》2013,32(1-3):251-263
Abstract Synthesis of 5-carbon-substituted 1-β-d-ribofuranosylimidazole-4-carboxamides are described. Treatment of 5-iodo derivative 8 with methyl acrylate in the presence of palladium catalyst gave (E)-5-(2-carbomethoxyvinyl)-1-(2,3,5-tri-O-acetyl-β-D-ribofuranosyl)imidazole-4-carboxamide (9), followed by appropriate manipulations to afford various 5-carbon-substituted imidazole derivatives 1–7. The antileukemic activities of these imidazole nucleosides are also described. 相似文献
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Takashi Kasai Takahiko Tokuda Takuma Ohmichi Ryotaro Ishii Harutsugu Tatebe Masanori Nakagawa Toshiki Mizuno 《PloS one》2016,11(1)
The COQ2 gene encodes an essential enzyme for biogenesis, coenzyme Q10 (CoQ10). Recessive mutations in this gene have recently been identified in families with multiple system atrophy (MSA). Moreover, specific heterozygous variants in the COQ2 gene have also been reported to confer susceptibility to sporadic MSA in Japanese cohorts. These findings have suggested the potential usefulness of CoQ10 as a blood-based biomarker for diagnosing MSA. This study measured serum levels of CoQ10 in 18 patients with MSA, 20 patients with Parkinson’s disease and 18 control participants. Although differences in total CoQ10 (i.e., total levels of serum CoQ10 and its reduced form) among the three groups were not significant, total CoQ10 level corrected by serum cholesterol was significantly lower in the MSA group than in the Control group. Our findings suggest that serum CoQ10 can be used as a biomarker in the diagnosis of MSA and to provide supportive evidence for the hypothesis that decreased levels of CoQ10 in brain tissue lead to an increased risk of MSA. 相似文献
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Shingo Hatakeyama Takuya Koie Takuma Narita Shogo Hosogoe Hayato Yamamoto Yuki Tobisawa Tohru Yoneyama Takahiro Yoneyama Yasuhiro Hashimoto Chikara Ohyama 《PloS one》2016,11(2)
ObjectivesTo assess the effects of urinary diversion on renal function, we retrospectively investigated renal function over 5 years after urinary diversion using a propensity score matching strategy.MethodsBetween May 1996 and November 2013, 345 consecutive adult patients underwent radical cystectomy and urinary diversion in our hospital; one hundred and fifteen patients with more than a 5-year follow-up were enrolled. Propensity scores were calculated using logistic analysis, and the data used in the analyses included age, gender, Eastern Cooperative Oncology Group Performance Status (ECOG-PS), clinical tumor stage, presence of cardiovascular disease; hypertension; and type 2 diabetes and preoperative eGFR at the initial visit. Multivariate logistic regression analysis was used to assess the risk factors for stage 3B chronic kidney disease (CKD) after the different types of urinary diversion.ResultsContinent and incontinent diversion were performed in 68 and 47 patients, respectively. The mean preoperative eGFR was significantly lower in the incontinent than in the continent group (P < 0.001). In propensity score-matched patients (n = 34 each), no significant differences were observed in pre- and postoperative eGFR and 5-year eGFR decrease rates between the groups. In the incontinent group, the number of postoperative stage 3B CKD patients was significantly increased than the continent group. Using multivariate analysis, independent risk factors significantly associated with stage 3B CKD at 5 years after surgery were older age, eGFR before surgery, incontinent diversion (cutaneous ureterostomy), and postoperative hydronephrosis.ConclusionsThe types of urinary diversion had no significant impact on renal function decline, whereas older age, preexisting impaired renal function, postoperative hydronephrosis, and cutaneous ureterostomy were independent risk factors for stage 3B CKD at 5 years after radical cystectomy. 相似文献