Evaluation effects of four cytotoxicity methods on in vitro inhibition of shikonin against tumor cells / 中草药

Objective To study the effects of four cytotoxicity evaluation methods on the inhibition rate of shikonin (SK) in vitro, and to compare the pseudo-negative phenomenon often found in the evaluation of cytotoxic activity of natural pigments represented by naphthoquinones in Lithospermum erythrorhizon. Methods SK was co-cultured with its high-sensitive strain HL-60 cells and low-sensitivity strain A549 cells, trypan blue method, sulforhodamine B (SRB) method, Cell Counting Kit-8 (CCK-8) and MTT cytotoxicity test were used for parallel experiments to determine the dose-effect relationship curve of SK (0.4-128 μmol/L) inhibiting the growth of cells. Results The half-inhibitory concentration (IC50) of shikonin on HL-60 cells was determined by trypan blue method, SRB method, CCK-8 method, and MTT method, which was 0.57, 0.77, 1.36, and 1.01 μmol/L, respectively. For A549 cells, the IC50 was 6.30, 10.38, 13.48, and 15.24 μmol/L, respectively. When the concentration of shikonin was below 3.2 μmol/L and 32 μmol/L, the inhibition rate of the two kinds of cells increased linearly by the four methods, followed by differences. Among them, the results of the trypan blue method and the SRB method are in good agreement, while the MTT method and the CCK-8 method have lower inhibition rates. At 12.8 μmol/L, the inhibitory rate of SK on HL-60 cell measured by CCK-8 was 81%, while the inhibitory rate measured by trypan blue method was 96%, and at 128 μmol/L the inhibitory rate of SK on A549 cells measured by MTT method was 89%, however, the inhibitory rate measured by trypan blue method was 99%. The absorption spectrum of SK overlapped with formazan at the wavelength from 400 to 600 nm, with the maximum overlap peak from 550 to 570 nm, and CCK-8 reagent had a synergistic inhibitory effect on HL-60 with SK. The results of trypan blue method showed that SK at the highest dose almost completely killed cells in the plate wells, which was significantly different from the control group, but both MTT method and CCK-8 method resulted in a pseudo-negative phenomenon. Conclusion Therefore, cytotoxicity test of natural pigments represented by naphthoquinones in L. erythrorhizon, MTT method, and CCK-8 method are not recommended, while SRB method and trypan blue method are suggested.

A method to improve success rate of mice melanoma metastasis model in vivo / 中国药理学通报

Aim To improve the rate of melanoma metastasis animal model and provide a reliable experimental modeling meth-od for the study of melanoma metastasis mechanism. Methods Five immunosuppressants were selected and then their targets were screened by network pharmacology. Intraperitoneal injection of immunosuppressants and intravenous injection of B16F10 cells were performed on C57BL/6 mice, then the mice were observed, and body weight were recorded daily. The contents of TNF-α, IL-6, IL-10, VEGF and MMP-9 in serum were measured with ELISA kit. The mice were dissected, then the metastasis situa-tion and the number of metastatic nodules in the lung and other organs were evaluated. HE-staining was involved to determine the morphology of metastatic tissues. Results The closeness centrality of cyclosporine and dexamethasone ranked the top and the targets were concentrated in lung and liver. No significant difference in body weight were observed after animal madel in-duced. The contents of TNF-α, IL-6 IL-10, VEGF and MMP-9 in the model group increased. The number of metastatic nodules in the lung significantly augmented with some kind of liver metas-tasis. HE-staining in the lung tissues showed that tumor presen-ted invasive growth. Conclusion By intraperitoneal injection of dexamethasone, the success rate of mice melanoma metastasis model can be greatly increased.

Association of AIRE gene polymorphisms with susceptibility to rheumatoid arthritis among ethnic Han Chinese from Shaanxi / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To assess the association of AIRE gene polymorphisms with rheumatoid arthritis (RA) among ethnic Han Chinese from Shaan'xi Province.</p><p><b>METHODS</b>Genomic DNA was prepared from 384 individuals with RA and 576 healthy controls. Four tag single nucleotide polymorphisms (SNP) in the AIRE gene (rs2075876, rs760426, rs1800520, and rs878081) were genotyped with a SNaPshot method. The genotypic and allelic frequencies were evaluated using a Chi square test. Genotyping data was corrected by Logistic regression for age and gender. The linkage disequilibrium (LD) block structure was examined using Hapview 4.2 software.</p><p><b>RESULTS</b>All 4 SNPs have conformed to Hardy-Weinberg equilibrium (P > 0.05). Two SNPs were significantly associated with RA, which included G allele of rs2075876 (OR=1.41, 95% CI: 1.17-1.71, P=3.7 × 10(-4)); Dominant model (OR=1.79, 95% CI: 1.21-2.63, P=0.002), Recessive model (OR=1.48, 95% CI: 1.14-1.93, P=0.003). rs760426 A risk allele (OR=1.26, 95% CI: 1.04-1.52, P=0.01); Recessive model (OR=1.33, 95% CI: 1.02-1.73, P=0.03). In addition, rs878081 and rs1800520 SNPs were not allele and genotyped polymorphisms were significantly associated with RA susceptibility.</p><p><b>CONCLUSION</b>The rs2075876 and rs760426 loci of the AIRE gene are associated with increased risk for rheumatoid arthritis among ethnic Han Chinese from ShaanXi.</p>

Causative Pathogens of Febrile Neutropaenia in Children Treated for Acute Lymphoblastic Leukaemia

<p><b>INTRODUCTION</b>Treatment of acute lymphoblastic leukaemia (ALL) using intensive chemotherapy has resulted in high cure rates but also substantial morbidity. Infective complications represent a significant proportion of treatment-related toxicity. The objective of this study was to describe the microbiological aetiology and clinical outcome of episodes of chemotherapy-induced febrile neutropaenia in a cohort of children treated for ALL at our institution.</p><p><b>MATERIALS AND METHODS</b>Patients with ALL were treated with either the HKSGALL93 or the Malaysia-Singapore (Ma-Spore) 2003 chemotherapy protocols. The records of 197 patients who completed the intensive phase of treatment, defined as the period of treatment from induction, central nervous system (CNS)-directed therapy to reinduction from June 2000 to January 2010 were retrospectively reviewed.</p><p><b>RESULTS</b>There were a total of 587 episodes of febrile neutropaenia in 197 patients, translating to an overall rate of 2.98 episodes per patient. A causative pathogen was isolated in 22.7% of episodes. An equal proportion of Gram-positive bacteria (36.4%) and Gram-negative bacteria (36.4%) were most frequently isolated followed by viral pathogens (17.4%), fungal pathogens (8.4%) and other bacteria (1.2%). Fungal organisms accounted for a higher proportion of clinically severe episodes of febrile neutropaenia requiring admission to the high-dependency or intensive care unit (23.1%). The overall mortality rate from all episodes was 1.5%.</p><p><b>CONCLUSION</b>Febrile neutropaenia continues to be of concern in ALL patients undergoing intensive chemotherapy. The majority of episodes will not have an identifiable causative organism. Gram-positive bacteria and Gram-negative bacteria were the most common causative pathogens identified. With appropriate antimicrobial therapy and supportive management, the overall risk of mortality from febrile neutropaenia is extremely low.</p>

Association of interferons regulatory factor 5 gene polymorphisms with rheumatoid arthritis in shaanxi ;Han Chinese population / 中华风湿病学杂志

Objective Previous studies have shown that genetic variants in the interferons regulatory factor 5 (IRF5) gene are associated with rheumatoid arthritis (RA) in European and Japanese, but not found in Han Chinese. We conducted this study to investigate whether genetic variants in the IRF5 gene are associated with RA in ShaanXi Han Chinese population. Methods This study was collected 576 RA patients and 768 normal controls. Six IRF5 gene polymorphisms (rs729302, rs2004640, rs752637, rs3807306, rs10954213 and rs2280714) were genotyped by the SNaPshot method. T-test and χ2 test were used for statistic analysis. The genotype and allele frequencies were evaluated using the chi square tests. Genotyping data were adjusted by Logistic regression method by age and gender. The linkage disequilibrium (LD) block structure was examined using Hapview 4.2 software. Results Six SNPs inspected complied with Hardy-weinberg equilibrium (P>0.05). Two SNPs were significantly associated with RA: rs729302 A risk allele [OR=1.29, 95%CI (1.10, 1.50), P=5.57×10-3];dominant model [OR=1.58, 95%CI (1.10, 2.27), P=0.024], recessive model [OR=1.31, 95%CI (1.17, 1.64), P=0.028]. rs2004640 T risk allele [OR=1.28, 95%CI (1.08, 1.54), P=0.039]; dominant model [OR=1.27, 95%CI (1.03, 1.58), P=0.036]. In addition, there was no significant difference in rs752637, rs3807306, rs10954213 and rs2280714 SNPs between RA group and control and genotyped polymorphisms were significantly associated with RA susceptibility. Conclusion The present study confirm that rs729302 and rs2004640 in the IRF5 gene is significantly associated with increased risk of RA in ShaanXi Han Chinese population.

Molecular regulatory mechanism of tooth root development / 国际口腔科学杂志·英文版

The root is crucial for the physiological function of the tooth, and a healthy root allows an artificial crown to function as required clinically. Tooth crown development has been studied intensively during the last few decades, but root development remains not well understood. Here we review the root development processes, including cell fate determination, induction of odontoblast and cementoblast differentiation, interaction of root epithelium and mesenchyme, and other molecular mechanisms. This review summarizes our current understanding of the signaling cascades and mechanisms involved in root development. It also sets the stage for de novo tooth regeneration.

Correlation between species-level identification of coagulase-negative staphylococci and accuracy of methicillin resistance coagulase-negative staphylococci detection / 中华检验医学杂志

Objective To evaluate accuracy of cefoxitin disk testing for detecting oxacillin resistance coagulase-negative staphylococci (MRCNS). Methods 139 clinical coagulase-negative staphylococci (CNS) were detected with ID32 STAPH. Cefoxitin disk and oxacillin disk testing were used to detect MRCNS. PBP2a was tested by latex agglutination us a reference method. Results 139 CNS isolates were identified to 8 species: Staphylococcus haemolyticus , S. epidermidis , S. hominis , S. xylosus , S. saprophyticus , S. auricularis , S. simulans and S. warneri. The sensitivity and specificity for cefoxtin disk and oxacillin disk testing were 99.0% vs. 86.0% and 91.7% vs. 74.4%, respectively. One S. epidermidis strain was identified to affect the sensitivity of cefoxitin disk testing. S. xylosus, S. warned, and S. saprophyticus were major species related to the decrease of specificity of cefoxitin disk testing. S. haemolyticus, S. hominis, S. simulans and S. auricularis were major species related to the decrease of sensitivity of oxacillin disk testing. And the decrease of specificity of oxacillin disk testing were mainly related to S. hominis , S. simulans , S. xylosus , S. auricularis , S. saprophyticus and S. warneri. Conclusions The accuracy of MRCNS detection by cefoxitin disk testing is varied due to different CNS species. So it is necessary to test PBP2a or mecA gene according to CNS species, especially for S. xylosus, S. warned and S. saprophyticus.