Hydrophobically modified biomineralized polysaccharide alginate membrane for sustained smart drug delivery

Hydrophobically modified biomineralized polysaccharide alginate membrane with smart drug release property using sodium palmitate as the hydrophobic component was prepared via a one-step method. The formation of CaHPO(4) in the membrane was clearly identified through scanning electron microscopy (SEM), energy dispersive X-ray spectrometer (EDS), X-ray diffraction (XRD) and Fourier transform infrared (FT-IR) spectroscopy. Indomethacin release profiles of the modified alginate membrane were found to be pH- and thermo-responsive. The drug release of modified alginate membrane was around 60% within 12 h, while that of the alginate membrane was higher than 90%. These results indicate that the hydrophobic and biomineralized polysaccharide components can hinder the permeation of the encapsulated drug and reduce the drug release effectively. The resulting membrane can be used as "smart" materials for sustained dual-responsive drug delivery.     

The Chiral Separation and Enantioselective Degradation of the Chiral Herbicide Napropamide

The chiral pesticide enantiomers often have different toxic effects and environmental behaviors, which suggests that the risk assessments should be on an enantiomeric level. In this work, the chiral separation of the napropamide enantiomers and the stereoselective degradation in tomato, cucumber, rape, cabbage, and soil were investigated. Napropamide enantiomers could be separated absolutely by high‐performance liquid chromatography (HPLC) using a Chiralpak IC column with a resolution factor of 11.75 under the optimized condition. Solid phase extraction (SPE) was used for cleanup of the enantiomers in the vegetable samples. The residue analysis method was validated. Good linearities (R² = 0.9997) and recoveries (71.43% ‐97.64%) were obtained. The limits of detection (LOD) were 0.05 mg/kg in soil and 0.20 mg/kg in vegetables. The results of degradation showed that napropamide dissipated rapidly in vegetables with half‐lives of only 1.13–2.21 days, but much more slowly in soil, with a half‐life of 11.95 d. Slight stereoselective degradation of the two enantiomers was only observed in cabbage, with enantiomeric fraction (EF) = 0.46, and there was no enantioselectivity in the other vegetables. The degradation of napropamide in the five matrixes was fast, and there was no enantioselectivity. Chirality 28:108–113, 2014. © 2014 Wiley Periodicals, Inc.     

Identification of a novel aFGF-binding peptide with anti-tumor effect on breast cancer from phage display library

It has been reported that acidic fibroblast growth factor (aFGF) is expressed in breast cancer and via interactions with fibroblast growth factor receptors (FGFRs) to promote the stage and grade of the disease. Thus, aFGF/FGFRs have been considered essential targets in breast cancer therapy. We identified a specific aFGF-binding peptide (AGNWTPI, named AP8) from a phage display heptapeptide library with aFGF after four rounds of biopanning. The peptide AP8 contained two (TP) amino acids identical and showed high homology to the peptides of the 182–188 (GTPNPTL) site of high-affinity aFGF receptor FGFR1. Functional analyses indicated that AP8 specifically competed with the corresponding phage clone A8 for binding to aFGF. In addition, AP8 could inhibit aFGF-stimulated cell proliferation, arrested the cell cycle at the G0/G1 phase by increasing PA2G4 and suppressing Cyclin D1 and PCNA, and blocked the aFGF-induced activation of Erk1/2 and Akt kinase in both breast cancer cells and vascular endothelial cells. Therefore, these results indicate that peptide AP8, acting as an aFGF antagonist, is a promising therapeutic agent for the treatment of breast cancer.     

miR-329 suppresses the growth and motility of neuroblastoma by targeting KDM1A

MicroRNAs (miRNAs) act as key regulators of multiple cancers. miR-329 functions as a tumor suppressor in some malignancies. However, its role in neuroblastoma remains poorly understood. We found that miR-329 was decreased in metastatic tumor tissues compared with matched primary tumor tissues. Forced overexpression of miR-329 substantially suppressed cell proliferation, colony formation, migration, and invasion of neuroblastoma cells. Lysine-specific demethylase 1 (KDM1A) was found to be a target of miR-329. Furthermore, down-regulation of KDM1A by shRNA performed similar effects with overexpression of miR-329. Overexpression of KDM1A partially reversed the tumor suppressive effects of miR-329 in neuroblastoma cells. Collectively, miR-329 may suppress neuroblastoma cell growth and motility partially by targeting KDM1A.     

上尿路腔内手术中降低肾盂压力机制与方法的研究进展

1983年,Wickham教授首先提出微创外科(minimally invasive surgery),此后,微创泌尿外科逐渐成外具有科学意义上的微创外科学的一个重要的分支学科。上尿路的腔内手术,包括PNL(Percutaneous nephrolithotomy)、URS(Ureteroscopic)、f-URS(Flexible ureteroscope)等。与传统手术相比,上尿路的腔内手术具有创伤小、时间短、恢复快、并发症少,并且可以直视下进行手术操作,临床应用较广泛。在腔内操作时,为保证术中手术视野的清晰度,手术多采用生理盐水(NS)进行灌注,进而导致肾盂压力升高,引起各项潜在的危害。因此如何在上尿路腔内手术中降低肾盂压力成为一个研究的热点。近些年,腔内器械的改进,包括镜体灌注通道入路与出路的分开设计、回流鞘的设计、压力泵的改进,在一定程度上降低了肾盂压力。灌注液体中加入相应浓度的药物,抑制上尿路平滑肌的蠕动与收缩,也在一定程度上降低了肾盂压力。本文介绍了上尿路腔内手术中肾盂压力的影响因素,回顾了肾盂压力升高后的危害,分析了肾盂压力升高机制,总结了肾盂压力降低的各种方案以及将来的应用前景。     

Dysregulated autophagy in the RPE is associated with increased susceptibility to oxidative stress and AMD

Autophagic dysregulation has been suggested in a broad range of neurodegenerative diseases including age-related macular degeneration (AMD). To test whether the autophagy pathway plays a critical role to protect retinal pigmented epithelial (RPE) cells against oxidative stress, we exposed ARPE-19 and primary cultured human RPE cells to both acute (3 and 24 h) and chronic (14 d) oxidative stress and monitored autophagy by western blot, PCR, and autophagosome counts in the presence or absence of autophagy modulators. Acute oxidative stress led to a marked increase in autophagy in the RPE, whereas autophagy was reduced under chronic oxidative stress. Upregulation of autophagy by rapamycin decreased oxidative stress-induced generation of reactive oxygen species (ROS), whereas inhibition of autophagy by 3-methyladenine (3-MA) or by knockdown of ATG7 or BECN1 increased ROS generation, exacerbated oxidative stress-induced reduction of mitochondrial activity, reduced cell viability, and increased lipofuscin. Examination of control human donor specimens and mice demonstrated an age-related increase in autophagosome numbers and expression of autophagy proteins. However, autophagy proteins, autophagosomes, and autophagy flux were significantly reduced in tissue from human donor AMD eyes and 2 animal models of AMD. In conclusion, our data confirm that autophagy plays an important role in protection of the RPE against oxidative stress and lipofuscin accumulation and that impairment of autophagy is likely to exacerbate oxidative stress and contribute to the pathogenesis of AMD.     

Akt2 Is Involved in Loss of Epithelial Cells and Renal Fibrosis following Unilateral Ureteral Obstruction

Obstructive nephropathy is an aggressive form of chronic kidney disease (CKD), which is characterized by an epithelial-to-mesenchymal transition (EMT) and interstitial fibrosis. However, the molecular mechanisms of EMT and fibrosis are complex and not fully understood. In this study, we investigated the contribution of Akt2 to experimental renal EMT and fibrosis using the well-established model of unilateral ureteral obstruction (UUO). We found that Akt2 and phosphor (p)-Akt protein levels were increased in the obstructed kidneys. UUO induced activation of transforming growth factor-β1 (TGF-β1) signaling. Importantly, knockout of Akt2 suppressed UUO-induced EMT, kidney fibrosis, increased GSK3β activity, and decreased expression of Snail and β-catenin. Inhibition of GSK3β with LiCl (the inhibitor of GSK3β) increased the expression of Snail and β-catenin in cultured kidney epithelial cells. Our findings suggest that Akt2 partially contributes to interstitial fibrosis following UUO and that inhibition of this signaling pathway may provide a novel approach of prevent progression of renal fibrosis.     

Prognostic Significance of Systemic Inflammation-Based Lymphocyte- Monocyte Ratio in Patients with Lung Cancer: Based on a Large Cohort Study

Increasing evidence indicates cancer-related inflammatory biomarkers show great promise for predicting the outcome of cancer patients. The lymphocyte- monocyte ratio (LMR) was demonstrated to be independent prognostic factor mainly in hematologic tumor. The aim of the present study was to investigate the prognostic value of LMR in operable lung cancer. We retrospectively enrolled a large cohort of patients with primary lung cancer who underwent complete resection at our institution from 2006 to 2011. Inflammatory biomarkers including lymphocyte count and monocyte count were collected from routinely performed preoperative blood tests and the LMR was calculated. Survival analyses were calculated for overall survival (OS) and disease-free survival (DFS). A total of 1453 patients were enrolled in the study. The LMR was significantly associated with OS and DFS in multivariate analyses of the whole cohort (HR = 1.522, 95% CI: 1.275–1.816 for OS, and HR = 1.338, 95% CI: 1.152–1.556 for DFS). Univariate subgroup analyses disclosed that the prognostic value was limited to patients with non-small-cell lung cancer (NSCLC) (HR: 1.824, 95% CI: 1.520–2.190), in contrast to patients with small cell lung cancer (HR: 1.718, 95% CI: 0.946–3.122). Multivariate analyses demonstrated that LMR was still an independent prognostic factor in NSCLC. LMR can be considered as a useful independent prognostic marker in patients with NSCLC after complete resection. This will provide a reliable and convenient biomarker to stratify high risk of death in patients with operable NSCLC.