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91.
Shingo Ito Yu Fujino Seiryo Ogata Mio Hirayama-Kurogi Sumio Ohtsuki 《Journal of pharmaceutical sciences》2018,107(12):3163-3170
The SLC22A18 gene, which encodes an orphan transporter, is located at the 11p15.5 imprinted region, an important tumor suppressor gene region. However, the role of SLC22A18 in tumor suppression remains unclear. Here, we investigated the involvement of SLC22A18 in cell growth, invasion, and drug resistance of MCF7 human breast cancer cell line. Western blot analysis indicated that SLC22A18 is predominantly expressed at intracellular organelle membranes. Quantitative proteomics showed that knockdown of SLC22A18 significantly altered the expression of 578 (31.0%) of 1867 proteins identified, including proteins related to malignancy and poor prognosis of breast cancer. SLC22A18 knockdown (1) increased MCF7 cell growth concomitantly with a >7-fold increase of annexin A8 (involved in cell growth and migration; a predictor of poor prognosis), (2) induced spherical morphology of MCF7 cells concomitantly with a nearly 3-fold increase of CD44 (involved in regulation of malignant phenotypes), and (3) increased chemosensitivity to vinca alkaloids concomitantly with a >80% reduction of doublecortin-like kinase 1 (involved in regulation of microtubule polymerization). Our results suggest that SLC22A18 may act as a tumor suppressor by regulating the expression levels of cell growth–related proteins, and vinca alkaloids might show therapeutic efficacy against low-SLC22A18–expressing breast cancer. 相似文献
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Kasirawat Sawangrat Masaki Morishita Kosuke Kusamori Hidemasa Katsumi Toshiyasu Sakane Akira Yamamoto 《Journal of pharmaceutical sciences》2018,107(11):2946-2956
Breast cancer resistance protein (BCRP) transporter is an efflux transporter that utilizes energy from adenosine triphosphate hydrolysis to push its substrates, regardless of the concentration gradient. Its presence on the apical membrane of the intestinal mucosa is a major obstacle for the intestinal absorption of its substrates. In this study, we examined the effects of various pharmaceutical excipients on the intestinal transport and absorption of sulfasalazine, a BCRP substrate. Four excipients, including 0.05% and 0.075% BL-9EX, 0.01% and 0.05% Brij 97, 0.075% Labrasol, and 0.05% and 0.1% Tween 20 decreased the secretory transport of sulfasalazine in an in vitro diffusion chamber. Further investigation in an in situ closed loop experiment in rats showed that 0.05% and 0.1% BL-9EX and 0.1% Brij 97 effectively enhanced the intestinal absorption of sulfasalazine while maintaining minimal toxicity to the intestinal mucosa. However, 0.1% Brij 97 also increased the intestinal absorption of 5(6)-carboxyfluorescein, a paracellular marker compound. These findings suggest that BL-9EX might effectively inhibit the BCRP-mediated efflux of sulfasalazine in vivo, indicating that BL-9EX could improve the intestinal absorption of sulfasalazine and other BCRP substrates. 相似文献
93.
Christian Luebbert Christian Klanke Gabriele Sadowski 《International journal of pharmaceutics》2018,535(1-2):245-252
The bioavailability of poorly-water-soluble active pharmaceutical ingredients (APIs) can be significantly improved by so-called amorphous solid dispersions (ASDs). However, the long-term stability of ASDs might be impaired by API recrystallization and/or amorphous phase separation (APS). So far, no methods have been reported to quantify APS in ASDs. In this work, phase-separation kinetics as well as the compositions of the two amorphous phases evolving due to APS were quantitatively determined for the first time using confocal Raman spectroscopy. Raman spectra were evaluated via non-linear multivariate Indirect Hard Modeling and verified by differential scanning calorimetry and hot-stage microscopy. APS in water-free ASDs of ibuprofen and poly (DL-lactic-co-glycolic acid) was investigated considering the influence of temperature and polymer architecture (linear vs. star-shaped). Water absorbed at 40?°C and 75% relative humidity (RH) promotes APS which was quantified for formulations of felodipine/poly(vinyl pyrrolidone) and ibuprofen/poly(vinyl pyrrolidone). 相似文献
94.
目的 探讨低出生体质量儿坏死性小肠结肠炎(NEC)的影响因素、手术疗效与预后。 方法 以2006年1月至2015年12月收治的146例低出生体质量NEC患儿为病例组,另采用随机数字表法选取同期在新生儿重症监护室(NICU) 住院治疗的146例非NEC低出生体质量儿为对照组。分析两组患儿的临床资料,采用单因素和多因素分析探讨NEC的影响因素,并分析NEC患儿中手术组与保守治疗组疗效的差异。 结果 多因素logistic回归分析显示,母乳喂养与喂服益生菌为NEC的保护性因素,先天性心脏病、败血症与输血是NEC的危险因素。手术组的好转率(95.45%)明显高于保守治疗组(85.00%)(P<0.05)。 结论 低出生体质量儿NEC的发病受多种因素影响,应针对其影响因素进行综合干预。适合的手术疗法能提高疗效,改善患儿的预后。 相似文献
95.
Rebekah L. Thomas Adrian B. Kelly Gary C. K. Chan Leanne M. Hides Catherine A. Quinn David J. Kavanagh 《Substance use & misuse》2018,53(13):2125-2131
Objective: To assess gender differences in the relationship between eating and weight loss attitudes (EWAs), and 30-day tobacco and alcohol use among adolescents, while controlling for potential confounds (age, country of birth, psychological distress, pubertal development, peer alcohol and tobacco use, and sexual activity). Methods: School students aged between 11 and 17 years (N = 10,273) from high schools in the State of Victoria (Australia) completed surveys in class under conditions of anonymity and confidentiality. Results: The interaction between EWAs and gender was significant for tobacco use but not for alcohol use, indicating that the effect of EWAs on tobacco use, but not alcohol use, vary by gender. Conclusions: Tobacco use was related to EWAs in adolescent females but not males, and this is consistent with the possibility that females use tobacco in an instrumental fashion to control weight. Implications and Contribution: Female adolescents high in eating and weight loss attitudes were more likely to engage in tobacco use. In contrast, eating and weight loss attitudes were not related to male tobacco use. These results point to the potential importance of developing gender-specific approaches towards addressing problematic behaviors in adolescent populations. 相似文献
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Direct Percutaneous Endoscopic Jejunostomy: Procedural and Nutrition Outcomes in a Large Patient Cohort 下载免费PDF全文
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