Targeted killing of CD133+ lung cancer stem cells using paclitaxel-loaded PLGA-PEG nanoparticles with CD133 aptamers / 南方医科大学学报

OBJECTIVE@#To construct a polylactic acid-glycolic acid-polyethylene glycol (PLGA-PEG) nanocarrier (N-Pac-CD133) coupled with a CD133 nucleic acid aptamer carrying paclitaxel for eliminating lung cancer stem cells (CSCs).@*METHODS@#Paclitaxel-loaded N-Pac-CD133 was prepared using the emulsion/solvent evaporation method and characterized. CD133+ lung CSCs were separated by magnetic bead separation and identified for their biological behaviors and gene expression profile. The efficiency of paclitaxel-loaded N-Pac-CD133 for targeted killing of lung cancer cells was assessed in vitro. SCID mice were inoculated with A549 cells and received injections of normal saline, empty nanocarrier linked with CD133 aptamer (N-CD133), paclitaxel, paclitaxel-loaded nanocarrier (N-Pac) or paclitaxel-loaded N-Pac-CD133 (n=8, 5 mg/kg paclitaxel) on days 10, 15 and 20, and the tumor weight and body weight of the mice were measured on day 40.@*RESULTS@#Paclitaxel-loaded N-Pac-CD133 showed a particle size of about 100 nm with a high encapsulation efficiency (>80%) and drug loading rate (>8%), and was capable of sustained drug release within 48 h. The CD133+ cell population in lung cancer cells showed the characteristic features of lung CSCs, including faster growth rate (30 days, P=0.001) and high expressions of tumor stem cell markers OV6(P < 0.001), CD133 (P=0.001), OCT3/4 (P=0.002), EpCAM (P=0.04), NANOG (P=0.005) and CD44 (P=0.02). Compared with N-Pac and free paclitaxel, paclitaxel-loaded N-Pac-CD133 showed significantly enhanced targeting ability and cytotoxicity against lung CSCs in vitro (P < 0.001) and significantly reduced the formation of tumor spheres (P < 0.001). In the tumor-bearing mice, paclitaxel-loaded N-Pac-CD133 showed the strongest effects in reducing the tumor mass among all the treatments (P < 0.001).@*CONCLUSION@#CD133 aptamer can promote targeted delivery of paclitaxel to allow targeted killing of CD133+ lung CSCs. N-Pac-CD133 loaded with paclitaxel may provide an effective treatment for lung cancer by targeting the lung cancer stem cells.

Rapid Identification of Alkaloids in Evodia rutaecarpa by HPLC-Q-TOF-MS/MS / 中国实验方剂学杂志

Objective:To obtain the information of alkaloids in Evodia rutaecarpa by HPLC-Q-TOF-MS/MS. Method:Inter Sustain-C18 column (4.6 mm×250 mm,5 μm) was used with 0.2% formic acid water-acetonitrile as the mobile phase for gradient elution. The column temperature was 25℃,the volume flow rate was 1.0 mL·min-1,and the sample volume is 5 μL. The detection wavelength was 245 nm,and the chromatographic effluent was detected and analyzed by using both positive and negative ions. Result:According to molecular ion peaks and secondary mass spectrometry characteristic fragment ions,as well as the mass spectrometry information of reference substances and relevant literature reports,more than 40 major peaks were analyzed,and 21 alkaloids were identified from the methanol extract of E. rutaecarpa, including 10 kinds of indole alkaloids,10 kinds of quinolone alkaloids,and 1 kind of ephedrine. Main types of alkaloids in E. rutaecarpa were basically clarified. And the research found that the alkaloids have a good response mainly in the positive mode. Conclusion:Based on HPLC-Q-TOF-MS/MS technology, high-performance liquid chromatography (HPLC) separation,mass spectrometry determination of molecular mass,pyrolysis data,literature analysis and retrieval were performed to quickly,accurately and comprehensively identify alkaloids in E. rutaecarpa, so as to provide a scientific basis for the further extraction and separation of the chemical constituents of E. rutaecarpa.

The metabolic profilings study of serum and spinal cord from acute spinal cord injury rats ¹H NMR spectroscopy / 中国骨伤

<p><b>OBJECTIVE</b>To establish the rat model of acute spinal cord injury, followed by aprimary study on this model with ¹H NMR based on metabonomics and to explore the metabonomics and biomarkers of spinal cord injury rat.</p><p><b>METHODS</b>Twenty eight-week-old adult male SD rats of clean grade, with body weight of (200±10) g, were divided into sham operation group and model group in accordance with the law of random numbers, and every group had 10 rats. The rats of sham operation group were operated without damaging the spinal cord, and rats of model group were made an animal model of spinal cord incomplete injury according to the modified Allen's method. According to BBB score to observate the motor function of rats on the 1th, 5th, and 7th days after surgery. Postoperative spinal cord tissue was collected in order to pathologic observation at the 7th day, and the metabolic profilings of serum and spinal cord from spinal cord injury rats were studied by ¹H NMR spectroscopy.</p><p><b>RESULTS</b>The hindlimb motion of rats did not obviously change in sham operation group, there was no significant difference at each time point;and rats of model group occurred flaccid paralysis of both lower extremities, there was a significant difference at each time; there was significant differences between two groups at each time. Pathological results showed the spinal cord structure was normal with uniform innervation in shame group, while in model group, the spinal cord structure was mussy, and the neurons were decreased, with inflammatory cells and necrotic tissue. Analysis of metabonomics showed that concentration of very low density fat protein (VLDL), low density fat protein (LDL), glutamine, citric acid, dimethylglycine (DMG) in the serum and glutathione, 3-OH-butyrate, N-Acetyl-L-aspartic acid (NAA), glycerophosphocholine (GPC), glutamic acid, and ascorbate in spinal cord had significant changes(<0.05).</p><p><b>CONCLUSIONS</b>There are significant differences in metabolic profile from serum and spinal cord sample between model group and sham operation group, it conduces to explain the changes of small molecular substances in serum and spinal cord tissue after spinal cord injury, this provides the research basis for targeted research on the role of metabolic markers in patients with acute spinal cord injury.</p>

Preparative resolution of gatifloxacin enantiomers with pre-column esterification strategy and comparing their enantioselectivity to bacteria and antibody / 生物医学与环境科学（英文）

Gatifloxacin (GFX) is a kind of chiral fluoroquinolones compound due to the methyl group at the C-3 position of the piperazine ring[1]. Although the enantiomers of GFX show similar levels of antimicrobial activity and pharmacokinetics[2], the other biological activities (i.e., toxicity or enantioselective recognition to various receptors in vivo) of GFX enantiomers have not yet been studied. With this in mind, we developed a rapid and cost-effective high performance liquid chromatographic (HPLC) separation procedure for GFX enantiomers with a pre-column esterification strategy. With significant enhancement of drug solubility and optimization for chromatographic conditions, the proposed method was scaled up to preparative HPLC to obtain optical active S-(-)- and R-(+)-GFX. The antibacterial activities of GFX enantiomers after preparative separation were further verified by measuring the Minimum Inhibitory Concentration (MIC) values against Escherichia coli ATCC 25922. In addition, the binding selectivity of GFX enantiomers to protein receptor were evaluated by antibody using enzyme-linked immunosorbent assay (ELISA) for the first time.

HPLC fingerprint of citri grandis exocarpium from different cultivars / 中国中药杂志

<p><b>OBJECTIVE</b>To study the quality difference among Citrus grandis 'Tomentosas' of different cultivars, in order to provide scientific basis for seeking for fine breeds.</p><p><b>METHOD</b>The HPLC fingerprints were established for C. grandis 'Tomentosa' of different cultivars in the GAP base of Huazhou Green Life Co., Ltd. The software of similarity evaluation system of traditional Chinese medicine HPLC fingerprints 2004A edition of Chinese Pharmacopoeia Commission was adopted for the similarity analysis and judgment of cultivars.</p><p><b>RESULT</b>The fingerprints showed similar general characteristics of samples of different cultivars. Specifically, the similarity of areas of the 18 common peaks ranged between 0.938-0.998. The success rate of judging cultivars using similarity software stood at 92%.</p><p><b>CONCLUSION</b>This method can be applied to better identify quality and source of cultivars of C. grandis 'Tomentosa', and provide technical measures and scientific basis for seeking for fine breeds of Citri Grandis Exocarpium.</p>