Preparation and physicochemical properties of PVA/HA composite microspheres for embolization / 国际生物医学工程杂志

Objective:To prepare polyvinyl alcohol (PVA) and hydroxyapatite (HA) composite embolization microspheres and investigate their physicochemical properties.Methods:PVA/HA composite embolization microspheres were prepared by reverse suspension polymerization, using PVA and HA as dispersed phases, liquid paraffin containing sorbitan fatty acid ester as the continuous phase, and glutaraldehyde as the cross-linking agent. The morphology, particle size distribution, and microscopic morphology of PVA/HA composite embolization microspheres were observed by optical microscopy and scanning electron microscopy. The chemical structure of PVA/HA composite embolization microspheres and the elasticity, drug loading, and drug release properties of PVA/HA composite bolus microspheres were characterized by Fourier infrared spectroscopy.Results:The PVA/HA composite embolization microspheres were internal, porous round spheres with a particle size distribution of 50-300 μm. The elastic properties of PVA/HA composite embolization microspheres were(13.6±0.145) kPa, which was 2.28 times that of PVA microspheres, and the drug loading capacity and encapsulation efficiency were (76.80±1.22) mg/g and (38.4±12.7)%, respectively. The maximum cumulative release rate of the microspheres within 7 days was (7.37±0.101)%, and the maximum cumulative release was (256.2±9.8) μg.Conclusions:PVA/HA composite embolization microspheres have good mechanical properties and drug-loading and drug-releasing properties, which provide an important reference for their use as medical devices.

Cytogenetic differences between adults and children with acute lymphoblastic leukemia: eight-probe fluorescence in situ hybridization and karyotype analyses / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the cytogenetic differences between children and adults with acute lymphoblastic leukemia (ALL) using eight-probe fluorescence in situ hybridization and karyotype analysis.</p><p><b>METHODS</b>Eight-probe (MYC, P16, E2A, TEL/AML1, BCR/ABL , MLL , IGH, and hyperdiploidy) fluorescence in situ hybridization and karyotype analysis were performed for 86 adults and 39 children with acute lymphoblastic leukemia.</p><p><b>RESULTS</b>Eight-probe fluorescence in situ hybridization showed significant differences in the positivity rate of TEL/AML1, BCR/ABL, and hyperdiploidy between adult patients and children with ALL. By karyotype analysis, the positivity rate of t(9;22) and hyperdiploidy differed significantly between the children and adult patients (P<0.05).</p><p><b>CONCLUSION</b>Adults and children with ALL have different expression profiles of the fusion genes. Eight-probe fluorescence in situ hybridization is time-saving, accurate and efficient in detecting common genetic abnormalities in ALL patients, and can be well complementary to karyotype analysis in clinical diagnosis of ALL.</p>

Identification of differentially expressed genes related to blastic crisis in chronic myeloid leukemia / 南方医科大学学报

<p><b>OBJECTIVE</b>To identify differentially expressed genes between chronic phase and blast crisis in chronic myeloid leukemia, explore the mechanism and screen potential biomarkers of disease progression.</p><p><b>METHODS</b>The differences in the gene expression profiles of bone marrow mononuclear cells between chronic phase and blastic crisis were examined using DNA microarray. PANTHER database, Genomatix database and Bibliosphere software were used to analyze and predict the critical genes or transcription factors during disease progression. Some of the genes or transcription factors were selected for verification by semi-quantitative RT-PCR.</p><p><b>RESULTS</b>In blastic crisis, 68 of the 1176 tested genes were obviously up-regulated. Sixteen of these differential genes were selectively expressed in leukocyte membranes. CD40, CCR3, LGALS3, RGS3, CEACAM3 and the related transcription factors RAC1, CTNNB1, TP53, and NF-κB, all as the nodes of the entire regulatory network, were presumed to play key roles in disease progression. The results of RT-PCR were consistent with the microarray data and showed high expression of CEACAM3, RGS3, CTNNB1 and RAC1 in blastic crisis.</p><p><b>CONCLUSION</b>A group of genes have been identified to very likely play key roles or serve as biomarkers in the transition from the chronic phase to blastic crisis in chronic myeloid leukemia.</p>