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BACKGROUND: Adipose-derived stem cells (ADSCs) can establish a favorable repair microenvironment by secreting abundant cytokines, which allows ADSCs to be a good source of seed cells for the treatment of ischemic diseases. OBJECTIVE: To investigate the changes of cytokines secreted by human ADSCs at passages 2-10. METHODS: After isolation and culture of ADSCs from human adipose tissue, the morphological features of cells were observed under inverted microscope. Human ADSCs were identified by the immunophenotypes and differentiation capability. RESULTS AND CONCLUSION: ADSCs were fusiform or polygonal in shape, with buging cell body, homogenized cytoplasm and clear nuclei, and could differentiate into adipocytes, osteocytes and chondroblasts in vitro. ADSCs at passage 3 were positive for CD29 (99.21%), CD73 (99.65%) and CD90 (99.92%), but negative for hematopoietic marker CD34 (2.25%). ELISA results showed that ADSCs at passage 5 had the highest secretion levels of vascular endothelial growth factor and hepatocyte growth factor, while ADSCs at passage 3 had the highest secretion level of brain-derived neurotrophic factor. To conclude, ADSCs have steady biological features of stem cells and exhibit good growth and proliferation potentials. ADSCs at different passages have different capacities in the secretion of vascular endothelial growth factor, hepatocyte growth factor and brain-derived neurotrophic factor. Passage 5 ADSCs show the highest ability to secrete vascular endothelial growth factor and hepatocyte growth factor, while passage 3 ADSCs show the strongest potential to secrete brain-derived neurotrophic factor.
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BACKGROUND:Endothelial progenitor cells are precursor cells of mature endothelial cells,which can migrate to ischemic tissues and differentiate into mature endothelial cells,and then play an important role in vascular remodeling.Endothelial progenitor cells have wide application prospects in various ischemic diseases,but the biological characteristics and identification methods are still controversial.OBJECTIVE:To investigate the methods of isolation and culture of endothelial progenitor cells from the human adipose tissue and to identify their biological features,in order to provide a sufficient source of cells for ischemic diseases.METHODS:Stromal vascular fraction cells were isolated from the human adipose tissue by enzymatic digestion,CD31+ cells were selected using immunomagnetic beads,and then cultured in endothelial basal medium-2 supplemented with the EGM-2-MV-SingleQuots.Endothelial progenitor cells were identified through detection of morphology,cell markers and cell functions.RESULTS AND CONCLUSION:(1) CD31 + cells were selected by immunomagnetic beads and then cultured and amplified in vitro,which displayed typical cobblestone-like morphology,and they maintain their proliferative ability.(2) Flow cytometry results showed that the CD31+ cells expressed CD31 (98.84％),CD34 (97.21％),VEGRR2 (64.07％),CD146 (98.42％) and CD133 (2.55％),but hardly expressed CD45 (1.1％),a hematopoietic stem cell marker.(3) The CD31 + cells were also found to incept Dil-ac-LDL and exhibit lectin binding capability.Furthermore,a lumen-like structure was formed in Matrigel,which has the ability of angiogenesis in vitro.To conclude,these results suggest that it is feasible to isolate and culture endothelial progenitor cells from the human adipose tissue by enzymatic digestion combined with immunomagnetic bead sorting.
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Objective: To prepare ginsenoside Rg3-loaded chitosan microspheres for intranasal administration. Methods: The chitosan microspheres were prepared by the O/W/O combined with multiple emulsification chemical crosslink technique. Quadratic polynomial equation and linear regression equation were fitted by the statistic software, and the resulting equations were used to produce response surface graphs. The best experiment conditions were screened by central composite design (CCD) using drug load, encapsulation efficiency, and the proportions of microspheres (with diameter of 40-60 μm) as variables. The shape of microspheres was observed by scanning electron microscope. Results: The best ranges of the prescription included: drug to carrier material ratio-0. 4-0. 5;organic phase and water phase ratio:0. 4-0. 6;and first emulsion and oil phase ratio:0. 13-0. 17. The 3 batches of microspheres prepared according to the above condition were well-shaped (full sphere), with the mean drug loading capacity being (10. 25 ± 0. 08) % and the encapsulation efficiency being (30. 61 ± 1. 46) %. Conclusion: The optimized technique has a good reproducibility and can be used for preparation of Rg3-loaded chitosan microspheres for intranasal administration.
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<p><b>OBJECTIVE</b>To evaluate the bioequivalence of tiopronin enteric capsules (testing preparation, T) versus tablets (reference preparation, R).</p><p><b>METHODS</b>A single oral dose of tiopronin enteric capsules or tablets at 200 mg was administered in 2 groups of Chinese healthy volunteers (n=9) in a randomized crossover design at the interval of 2 weeks. The plasma concentrations of tiopronin were measured by HPLC-MS/MS, and the pharmacokinetic parameters were calculated by DAS 2.0 program. The bioequivalence between the two preparations was evaluated.</p><p><b>RESULTS</b>The main pharmacokinetic parameters were as follows: C(max)(microg.ml(-1)) 3.612-/+1.2393 (R), 3.644-/+1.540 (T); t(max) 4.333-/+1.0853 (R), 3.611-/+1.420 (T); t((1/2))(h) 18.245-/+11.270 (R), 23.403-/+10.500 (T); AUC0-t (microg.h.ml(-1)) 18.732-/+6.92318 (R), 18.713-/+6.585 (T); AUC0-infinity (microg.h.ml(-1)) 21.900-/+7.31220 (R), 20.780-/+7.965 (T). The relative bioavailability of tiopronin enteric capsule was 103.712-/+23.956%, with 90% confidential intervals of ln(AUC0-->72), ln(AUC0-infinity) and ln(C(max)) of 91.1%-111.8%, 96.8%-118.3%, and 85.1%-113.0%, respectively.</p><p><b>CONCLUSION</b>The tiopronin enteric capsules were bioequivalent to the tablets.</p>
Subject(s)
Humans , Male , Young Adult , Biological Availability , Capsules , Cross-Over Studies , Health , Linear Models , Reproducibility of Results , Therapeutic Equivalency , Tiopronin , PharmacokineticsABSTRACT
<p><b>OBJECTIVE</b>To establish an liquid chromatography-mass spectrometry (HPLC-MS/MS)-based method for determining escitalopram in human plasma.</p><p><b>METHODS</b>A liquid-liquid ether extraction approach was adopted using dextromethorphan as the internal standard. The Agilent ZORBAX SB-C18 (3.5 microm,2.1 x 150 mm) was used as the analytical column with acetonitrile-NH4AC buffer (70:30, V/V) as the mobile phase at the flow rate of 0.3 ml/min. The sample was ionized by electrospray ionization source in the triple quadruple tandem mass spectrometer, and the plasma escitalopram determined with a multiple reaction monitoring mode of m/z325.4-->109.4.</p><p><b>RESULTS</b>The linear range was 0.0866-64.13 microg/L (r=0.9965) for escitalopram in human plasma, with the absolute recovery between 64.98% and 78.72% and the within-day and between-day deviations less than 10%.</p><p><b>CONCLUSION</b>The method is sensitive, accurate, rapid, specific and well applicable for clinical pharmacokinetics study of escitalopram.</p>