Effects of sub-micro emulsion composition on cellular disposition of incorporated lipophilic drug / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To investigate the effects of sub-micro emulsion composition on cellular uptake and disposition of incorporated lipophilic drug.</p><p><b>METHODS</b>Sub-micro emulsions containing 10 % oil, 1.2 % lecithin and 2.25 % glycerol were prepared, and the fluorescent agent coumarin 6 was used as a model drug. The effects of oil types, co-surfactants and cationic lipid on uptake and elimination kinetics of 6-coumarin in HeLa cells were studied. The uptake mechanism of sub-micro emulsions was further investigated.</p><p><b>RESULTS</b>Oil type and Tweens had no influence on the cellular uptake. Modifications of surfactants with Span series increased the cellular influx, among which Span 20 with hydrophilic-lipophilic balance (HLB) value of 8.6 was the best enhancer. The intracellular drug level reached up to (46.09 ± 1.98)ng/μg protein which had significant difference with control group [(38.54 ± 0.34)ng/μg protein]. The positively charged emulsions significantly increased the uptake rate constant and elimination rate constant which were 4 times and 1.5 times of those in anionic groups, respectively. The uptake enhancement was also observed in cationic emulsions, cellular concentrations at plateau were (42.73 ± 0.84)ng/μg protein, which was about 3 times of that in anionic emulsions [(15.71 ± 0.74)ng/μg protein], when extracellular drug concentration kept at 100 ng/ml. Cationic emulsions delivered the payload mainly by direct drug transfer to contacted cells, while the negative ones depended on both drug passive diffusion and clathrin-mediated endocytosis of drug containing oil droplets which accounted for 20% of the intracellular drug.</p><p><b>CONCLUSION</b>Interfacial characteristic of sub-micro emulsions such as co-surfactants HLB as well as zeta potentials can influence lipophilic drug both in cellular uptake and elimination.</p>

Preparation of a zinc porphyrinated nanofibrous membrane and its ammonia sensing property / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To prepare a zinc porphyrinated polyimide nanofibrous membrane for rapid detection of trace amount of ammonia.</p><p><b>METHODS</b>Zinc porphyrin chromophore was copolymerized into polyimide backbones and the according nanofibrous membrane was prepared by electrospinning technique. Ammonia detection was achieved by recording the color and spectral changes of the membrane before and after exposing to the target gas. The sensitivity, selectivity and detection limit of prepared membrane were further studied.</p><p><b>RESULTS</b>The obtained nanofibrous membrane preserved typical photophysical properties of zinc porphyrin chromophores. When exposed to ammonia, a dual chromo and spectrum responses of the nanofibrous membrane were observed. The binding affinity constant and the detection limit of zinc porphyrinated polyimide nanofibrous membrane calculated from surface plasmon resonance (SPR) analysis and UV-vis were 3.33 X10³ L/mol and 3.13 mg/m³, respectively.</p><p><b>CONCLUSION</b>The membrane prepared in this study exhibits good sensitivity, selectivity and reproducibility towards ammonia detection.</p>

Porphyrinated polyimide nanofibrous membrane for rapid detection of trace amount of methanol vapor / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To prepare novel electrospun porphyrinated polyimide nanofibrous membrane for rapid detection of trace amount of methanol vapor.</p><p><b>METHODS</b>Porphyrin chromophore was copolymerized into polyimide backbones and the porphyrinated polyimide nanofibrous membrane was prepared by electrospinning technique. By optimizing the processing parameters, such as solution concentration and electrospinning voltage, nanofibrous membrane with three dimensional and large surface-to-area ratio structure was fabricated for trace amount of methanol vapor sensing applications.</p><p><b>RESULTS</b>The obtained nanofibrous membrane preserved typical photophysical properties of porphyrin chromophores with uniformly fine and smooth fiber diameter. When exposed to methanol vapor, a red-shift of the absorption spectra and decrease in the emission intensities was observed, while no significant changes were seen when the membrane contacting with other common alcohols. After five times of 150 ppm methanol vapor quenching and nitrogen gas regeneration, the fluorescence of the membrane remained unchanged, indicating a good reversibility.</p><p><b>CONCLUSION</b>Combining the specific optical properties of porphyrin with large surface-area-to-volume ratio of nanofibrous membranes, a porphyrinated polyimide nanofibrous membrane has been facilely fabricated for trace methanol vapor detection. The sensing membrane exhibits good sensitivity, selectivity and reproducibility.</p>

Proteomic analysis of myocardial hypertrophy induced by left kidney artery coarctation in rats / 中国应用生理学杂志

<p><b>AIM</b>To identify the expression of proteins in cardiomyocytes in rats with left kidney artery coarctation.</p><p><b>METHODS</b>16 male SD rats were separated into 2 groups (n=8): 2 kidney 1 Clip group (2K1C) and sham operation group (SO). The postoperational 8th week, after examination by normal doppler and tissue doppler echocardiography, the extracted proteins from cardiomyocytes were isolated by two-dimensional gel electrophoresis with staining. The gel images were acquired by scanner and 2-DE analysis software. Different spots observed on two 2D gels were selected and identified by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS).</p><p><b>RESULTS</b>Overall, 21 protein spots showed significant difference, and 14 out of which were identified.</p><p><b>CONCLUSION</b>Kidney artery coactation-induced cardiac hypertrophy displays different expression of proteins in cardiomyocytes.</p>