Objective To analyze the genomic sequences of Cryptococcus neoformans var grubii strains of two genotypes with different virulence and to screen out the virulence-associated genes. Methods A clinical strain (IFM56800) with the strongest virulence and an environmental strain (IFM56731) with the weakest virulence were screened out for whole genome sequencing analysis. The results of sequencing analy-sis were comprehensively analyzed by using the method of comparative genomics. Genetic variations were ex-tensively screened by using the strategies of non-synonymous single nucleotide polymorphisms ( nsSNPs), nonsense SNPs and the insertions or deletions ( InDels) causing frameshift mutations. The filtered genes were sequenced in 20 experimental strains. The whole RNAs were extracted and then the full-length cDNAs were sequenced by using the rapid amplification of 5′ and 3′ cDNA ends (RACE) method. Results By whole genome sequencing, valid data with high coverage (127 times and 111 times) was obtained in both the environmental strain IFM56731 and the clinical strain IFM56800. The data of InDels and SNPs were statisti-cally analyzed, respectively. Six genes were chosen for further analysis based on the strategies of nonsense SNPs and the InDels causing frameshift mutations. The six genes were amplified and sequenced in all of the experimental strains, three of which were further analyzed with cDNA sequencing. Ultimately, the location and structure of CNAG_01032 gene were determined. The predicted nonsense mutation locus was verified to present in the actual mRNA. Conclusion The strategies of nonsense SNPs and the InDels causing frame-shift mutations showed high-efficiency in screening potential virulence-associated genes. The CNAG_01032 gene was screened out as a novel virulence-associated gene.

Objective To investigate the genotype distribution of microsatellite locus CAI among Candida albicans ( C.albicans ) strains and to evaluate its relationship with the epidemic of vulvovaginal candidiasis ( VVC) in Guizhou region .Methods Ninety independent C.albicans strains isolated from pa-tients with VVC in Guizhou were investigated based on single-strand conformation polymorphisms ( SSCP ) and GeneScan analysis .The genotypes of C.albicans strains were identified by microsatellite locus CAI pol-ymorphism analysis .The gene polymorphism and the cluster of C.albicans strains were analyzed by using software SPSS 19.0.A logistic regression model was used to analyze the relationship between genotype distri -bution of CAI microsatellite among C.albicans strains and VVC infection .Results Twenty-seven distinct CAI genotypes with various patterns were identified from 90 C.albicans strains by GeneScan analysis .Clus-ter analysis showed that the C.albicans strains were classified into three clusters ( ClusterⅠto Cluster Ⅲ) . Three predominant genotypes including 30-45, 32-46 and 30-46 and other 7 highly similar genotypes be-longed to clusterⅡthat accounted for 70.0%(63 strains) in all strains.The odds ratio for the predominant genotypes associated with VVC infection was 4.3.Conclusion The predominant distribution of genotypes was observed among the isolated C.albicans strains.The predominant genotypes of C.albicans were highly associated with the occurrence of VVC .

Molecular beacon probe was designed based on a specific DNA sequence of Nocardia to PCR detection of thisbacterium.The strains of Nocardia、Gordina and Rhodococcus were inoculated in Brain Heart Infusion Agar medium separately,then the growth condition was observed,DNA was extracted as a template;the molecular beacon probe was designed based on the partial secA 1 gene sequences of Nocardia strains,and the probe was added into the reaction system of real time fluorescence quantitative PCR (RT-PCR),and the fluorescence signal was tested at the end of PCR.Showed that the amplified secA1 gene of Nocardia could produce positive fluorescence signal in RT-PCR,but those of Gordonia and Rhodococcus with control groups showed negative results because of no fluorescence signal.In conclusion as a housekeeping gene,secA1 is an ideal target molecule to identify the actinomycetes strains on the species level in the systematic evolution research,and the technique of fluorescence molecular beacon probe is accurate,rapid and sensitive for detecting the Nocardia strains with secA1 gene.

Objective To investigate the genetic relation between Cryptococcus neoformans var.the clinical strains in MLMT - 13 genotype and the environmental strains in MLMT - 36 genotype. Methods Multilocus microsatellite typing (MLMT) method was applied for the genotype analysis in our study.Through this method, we recognized two genotypes that distinguish a majority of clinical and environmental strains. In order to compare virulence between the two types, we chose to infect BALB/c mice (6 weeks,female) with 9 MLMT-13 strains and 10 MLMT-36 strains intravenously. Results Forty( 17 clinical and 23 environmental isolates) were analyzed. Of 17 clinical strains, 9 belonged to a major type of MLMT-13 (52.9%). They were mainly isolated from clinical specimens. About 43.5% of strains from the environment belong to a major type of MLMT-36, which are indigenous to environments and which were not isolated from clinical samples. The mortality rate and pathological changes of the above mice were observed during two months after injection. The results showed that the mortality rate of mice infected with MLMT-13 strains was 100%, while the mortality rate with MLMT-36 strains was 7. 5%. The pathological sections showed that lesions of MLMT-13 infected mice appeared in the brain, lungs, liver and kidneys, while the lesions of MLMT-36 infected mice only appeared in the brain. Most brains of MLMT-13 infected mice were distorted,and both the number and size of lesions in such brains were much larger than those of MLMT-36 infected mice. Conclusion Our study illustrated the virulent difference between MLMT-13 and MLMT-36, which are isolated from patients and environment respectively. The results inferred that some genetic changes, such ss microsatellite repeats, might occur between environmental and clinical isolates through their environmental adaptation progress.

Objective To investigate the effects of an ar?turmerone derivative(ATD)on the proliferation and apoptosis of A375 human melanoma cells. Methods Both A375 cells and human skin fibroblasts (HSFs) were cultured with different concentrations(5, 10, 20, 40 and 80μmol/L)of ATD, vincristine and ar?turmerone, separately, for 48 hours in vitro. Subsequently, cell counting kit?8 (CCK?8) was used to evaluate cell proliferation, inverted microscopy to observe cell morphology after acridine orange/ethidium bromide (AO/EB) staining, and a colorimetric method to estimate caspase?3 activity. DNA fragmentation assay and flow cytometry were performed to assess cell apoptosis, and flow cytometry was conducted to analyze cell cycle. Results ATD, vincristine and Ar?turmerone all inhibited the proliferation of A375 cells in a dose?dependent manner(ATD:R2=0.99, F=340.96, P<0.05;vincristine:R2=0.99, F=349.19, P<0.05;ar?turmerone:R2=0.89, F=25.41, P<0.05). The fifty percent inhibitory concentra?tions(IC50s)of ATD, vincristine and ar?turmerone against A375 cells were 15.96 ± 0.02μmol/L, 77.00 ± 0.04μmol/L and 356.95 ± 0.01μmol/L respectively. When the drug concentrations were 5 and 10μmol/L, the proliferation of HSFs was inhibited by 8%± 0.06%and 25%± 0.02%respectively by ATD, by 49%± 0.09%and 34%± 0.07%respectively by ar?turmerone, and by 33%± 0.04%and 29%± 0.08%respectively by vincristine, and the proliferation of A375 cells was inhibited by 26%± 0.06%and 39%± 0.02%respectively by ATD, by 6%± 0.09%and 10%± 0.07%respectively by ar?turmerone, and by 8% ± 0.04% and 17% ± 0.08% respectively by vincristine, with the inhibitory effects of the three drugs being significantly different from that of dimethyl sulfoxide(all P<0.05). ATD showed stronger inhibitory effects on the proliferation of A375 cells, but weaker cytotoxic effects on HSFs compared with ar?turmerone and vincristine(all P<0.05). Meanwhile, ATD, vincristine and ar?turmerone all induced the apoptosis of A375 cells(P<0.05), and caspase?3 activity increased with the increase in drug concentrations(ATD:R2=0.98, F=162.30, P<0.05;vincristine:R2=0.96, F=94.39, P<0.05;ar?turmerone:R2=0.95, F=57.35, P<0.05). The effect of ATD on caspase?3 activity was strongest, followed by that of vincristine and ar?turmerone. As flow cytometry showed, all the three drugs induced cell apoptosis to different degrees, and ATD showed a relatively strong effect on cell apoptosis, especially late apoptosis, compared with the other two drugs. In the ATD group, the number of A375 cells in G1 phase gradually increased, while that in G2 phase and S phase significantly decreased with the increase in drug concentrations. Conclusions ATD exhibited proliferation?inhibiting and apoptosis?inducing effects on A375 cells, and the effects were stronger than those of vincristine and ar?turmerone. It is quite possible that ATD affects cell proliferation and differentiation by activating caspase?3 and arresting cell cycle in the G1 phase.

Objective:To study the differentially expressed proteins in saliva of health people and the patients with oral squamous cell carcinoma(OSCC).Methods:Saliva of 17 cases with OSCC and paired health subjects was collected,the proteins in the saliva were examined by two-dimensional gel electrophoresis (2-DE) separation,the proteins were examined by 2-DE separation,the saliva proteome dimensional electrophoresis profiles were obtained by MALDI-TOF/MS mass spectrometric identification,the information of the differentially expressed protein in OSCC group was studied by NCBI database bioinformatics analysis.Results:10 proteins differentially expressed between the 2 groups were observed by mass spectrometry.Bioinformatics analysis showed that S100A8,S100A8/S100A9 and Epidermal cytokeratin 2(EK2) were highly expressed in the saliva of OSCC cases.Conclusion:S100A8,S100A8/S100A9 and EK2 may be related to the development of OSCC.