[The Effect of Improved Culturing Method on the Detection Rate of Chromosome Karyotyping in Multiple Myeloma].

OBJECTIVE: To investigate an improved culturing method for karyotyping analysis, and increase the detection rate of cytogenetic abnormalities in patients with multiple myeloma (MM), so as to provide more powerful information for the clinical diagnosis, prognosis stratification, and individualized treatment of MM patients. METHODS: Eighty newly-diagnosed MM patients were enrolled and divided into two groups. In observation group, IL-6 (10 ng/ml) and GM-CSF (30 ng/ml) were supplemented in the culture medium, while no stimulating factor was added in control group. The samples from both groups were cultured for 72 hours under the same conditions, and their karyotypes were analyzed by G-banding. The detection rate of the cytogenetic abnormalities, as well as the corresponding characteristics were compared between the two groups. RESULTS: The detection rate of the chromosome aberrations was greatly increased in the observation group compared with the control group, the overall detection rate was 72.5% and 22.5%, respectively, as well as 80.0% and 19.2% in the subgroup of ≤60 years old, 68.0% and 28.6% in the subgroup of > 60 years old, which showed significant statistical differences (P<0.05). CONCLUSION: The modification of the culturing method with the addition of IL-6 (10 ng/ml) and GM-CSF (30 ng/ml) dual stimulating factors followed by incubation for 72 hours can effectively increase the detection rate of abnormal karyotypes in MM patients.

Peroxyl radical induced membrane instability of giant unilamellar vesicles and anti-lipooxidation protection.

The present work is intended to investigate the morphological instability of lipid membrane induced by peroxyl radical (ROO•) and the underlying mechanism. To this end, the giant unilamellar vesicle (GUV) made from phosphatidylcholine was employed as a membrane model, and the azo compounds 2,2'-azobis(2,4-dimethylvaleronitrile) (AMVN) and 2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH) were used as the precursors of ROO•. Upon mild pyrolysis, the GUV immobilized in agarose gel was followed by conventional optical microscopy in real time, and the morphological variation was quantified by the image heterogeneity, perimeter and area all as a function of time for up to an hour. Lipid oxidation initiated from lipid phase with AMVN and from aqueous phase with AAPH led to different types of morphological changes, i.e. membrane coarsening and vesicle deformation/budding, respectively. Based on the compositional analysis of lipid oxidation products, we propose that ROO• as the primary radical initiator is responsible for the morphological changes of the GUV-AMVN while both ROO• and RO• are responsible for the morphological changes of the GUV-AAPH system. Lipophilic ß-carotene and amphipathic plant phenols as antioxidants are found to be able to stabilize the membrane integrity effectively, in corroboration with the proposed mechanisms for membrane destruction.

[Knock-down of Pre-mRNA Splicing Factor Prp19 Causes Chromosome Misalignment and Prometaphase Arrest].

OBJECTIVE: To verify the role of the newly identified mitotic regulator candidate pre-mRNA processing factor 19 (Prp19) in mitosis and to clarify its underlying mechanism. METHODS: FACS analyses with propidium iodide (PI) staining were performed to evaluate the effect of Prp19 knockdown on cell cycle distribution. To further clarify the role of Prp19 in mitosis, the effect of Prp19 depletion was monitored by time-lapse imaging of HeLa/GFP-H2B cells. Cold treatment experiment was used to examine the effect of Prp19 knockdown on the attachment of microtubules and kinetochores. To evaluate the effect of Prp19 knockdown on cell apoptosis, the control and Prp19-knockdown cells were analyzed by FACS with annexin V-FITC/-PI double staining. Furthermore, Western blot analysis of cleaved caspase-3 and PARP was also performed. RESULTS: Prp19 knockdown causesd mitotic arrest. Time-lapse imaging analysis showed that depletion of Prp19 in HeLa cells results in prometaphase arrest and chromosome misalignment. Cold treatment experiment showed that attachment between kinetochore and microtubule was impaired by Prp19 knockdown. Moreover, the depletion of Prp19 leaded to cell apoptosis in cancer cells. CONCLUSION: Prp19 is a key regulator of mitotic progression, and its inhibition may provide a new strategy for anti-cancer therapy.

Assessment of heavy metal pollution in surface soils of urban parks in Beijing, China.

Assessing the concentration of potentially harmful heavy metals in the soil of urban parks is imperative in order to evaluate the potential risks to residents and tourists. To date, little research on soil pollution in China's urban parks has been conducted. To identify the concentrations and sources of heavy metals, and to assess the soil environmental quality, samples were collected from 30 urban parks located in the city of Beijing. Subsequently, the concentrations of Cu, Ni, Pb and Zn in the samples were analyzed. The investigation revealed that the accumulations of Cu and Pb were readily apparent in the soils. The integrated pollution index (IPI) of these four metals ranged from 0.97 to 9.21, with the highest IPI in the densely populated historic center district (HCD). Using multivariate statistic approaches (principal components analysis and hierarchical cluster analysis), two factors controlling the heavy metal variability were obtained, which accounted for nearly 80% of the total variance. Nickel and Zn levels were controlled by parent material in the soils, whereas Cu, Pb and, in part, Zn were accounted for mainly by anthropogenic activities. The findings presented here indicate that the location and the age of the park are important factors in determining the extent of heavy metal, particularly Cu and Pb, pollution. In addition, the accumulation of Zn did not appear to reach pollution levels, and no obvious pollution by Ni was observed in the soils of the parks in Beijing.