Objective An analytical approach has been developed for determination of sildenafil blood with high performance liquid chromatography.Methods Sildenafil was extracted by solid phase extraction cartridges from blood and was separated by resered-phase gradient chromatography with DAD detection at 230nm.The analytical column was Nova-pak C18(150×3.9mm),5.0μm and the guard column was Phenomenex C18(ODS,4.0×3.0mm,Octadecyl).The mobile phase Was gradient mixture of acetonitrile(A) and 0.25% acetonitrile aqueous solution including 0.06% trifluoroacetic acid and 0.06% triethylamine (B).Results Linearity Was checked over the concentration range 1.5～80.0μg/mL.Limits of detection was 5.0ng.Average recovery was 82.45%.Conclusion This method issimple.exact and rapid.

Objective To investigate the molecular genetic causes and their characteristics of deafness from patients with nonsyndromic hearing loss in Gansu province.Methods Peripheral blood samples were obtained from a total of 375 patients with nonsyndromic hearing loss to extract genomic DNA.Three genes of GJB2, mitochondrial DNA 12SrRNA, and SLC26A4 were screened for mutations in our study cohort using SNPscan technology.Results Among 375 patients, 23 patients were found to carry the homoplasmic mtDNA12SrRNA A1555G mutation, and 2 patients were detected to carry the homoplasmic mtDNA12SrRNA C1494T mutation.Forty-two cases(11.2%) were caused by GJB2 mutations, including 31cases(8.3%) of homozygous mutations, 11 patients(2.9%) of compound heterozygous mutations, and 25 cases(6.7%) of single homozygous mutations.c.235delC was the most prevalent GJB2 mutation with the allele frequency of 8.8%.Twenty-nine cases (7.7%) were caused by SLC26A4mutations, including 17cases(4.5%) of homozygous mutations, 12 patients(3.2%) of compound heterozygous mutations, and 16 cases(4.3%) of single homozygous mutations.c.919-2A>G and c.2168A>G were the most common SLC26A4 mutation, the allele frequencies were 5.2% and 2.0%, respectively.Conclusion A high incidence of mtDNA12SrRNAA1555G mutation is found in nonsyndromic hearing loss patients from Gansu province, while the incidence of GJB2 and SLC26A4 mutations is similar to the level of the overall Chinese deaf population.These findings demonstrate that a total of 25.6% of deaf patients have inherited hearing impairment caused by GJB2, SLC26A4, and mitochondrialDNA12SrRNA mutations.As a result 36% patients and family member can acquire effective genetic counseling.

Objective To probe into the influence of polysaccharides of Luotuopeng (Peganum harmala L.,Herb of Common Peganum) on toxicity of PolyQ accumulation in the muscle cells of AM141 strain of Caenorhabditis elegans (C.elegans).Methods The polysaccharides of Luotuopeng were extracted by using water extraction followed by sequential alcohol deposition method,and the content of each precipitation was determined by using phenol-sulfuric acid method.The polysaccharides were added to medium,and then samples were collected for counting the number of fluorescence dots due to PolyQ-YFP accumulation in the muscle cells of C.elegans.The influence of the polysaccharides on toxicity of PolyQ accumulation in AM141 strain of C.elegans was reviewed.The precipitation precipitated by 60％ ethanol with higher activity was purified by using macroporous resin for re-reviewing the activity.Results The mass fractions of the polysaccharides precipitated by 30％ ethanol,60％ ethanol or 80％ ethanol were,respectively,20.07％,21.80％,19.98％.The inhibition rates of the polysaccharides on the fluorescence dots due to PolyQ-YFP accumulation in the muscle cells of C.elegans were,respectively,7.9％,17％ and-1.72％.After the precipitation precipitated by 60％ ethanol purified with macroporous resin,the mass fractions of the polysaccharides,in 10％ and 20％ ethanol elution with higher mass fractions,were,respectively,49.76％ and 38.26％,and the inhibition rates were,respectively,35.25％ and 18.03％.Conclusion The method for reviewing the influence of the polysaccharides on toxicity of PolyQ accumulation through model of AM141 strain of C.elegans is easy,stable and reliable.The polysaccharide precipitated by 60％ ethanol has the highest inhibitory effect on PolyQ accumulation with a dose-effect relationship.