Objective To evaluate the value of PowerPlex（R）21 System (Promega) and study the genetic polymorphism of its 20 short-tandem repeat (STR) loci in southern Chinese Han population.Methods We conducted genotyping experiments using PowerPlex(R)21 System on 20 autosomal STR loci (D3S1358,D1S1656,D6S1043,D13S317,Penta E,D16S539,D18S51,D2S1338,CSF1PO,Penta D,TH01,vWA,D21S11,D7S820,D5S818,TPOX,D8S1179,D12S391,D19S433 and FGA) in 2367 unre1ated Chinese Han individuals living in South China.The allele frequencies and parameters commonly used in forensic science were statistically analyzed in these individuals and compared with the reported data of other populations.Results The PowerPlex（R） 21 System had a power of discrimination (PD) ranging from 0.7839 to 0.9852 and a power of exclusion (PE) ranging from 0.2974 to 0.8099 for the 20 loci.No significant deviation from Hardy-Weinberg expectations was found for all the loci except for D5S818.This southern Chinese Han population had significant differences in the allele frequencies from 8 ethnic groups reported in China,and showed significant differences at 8 to 20 STR foci from 5 foreign populations.The allele frequency at the locus D1S1656 in this southern Chinese Han population differed significantly from those in the 5 foreign populations and from 3 reported Han populations in Beijing,Zhejiang Province and Fujian Province of China.The neighbor-joining phylogenetictree showed clustering of all the Asian populations in one branch,while the northern Italian and Argentina populations clustered in a separate branch.This southern Chinese Han population had the nearest affinity with the Yi ethnic population in Yunnan Province of China.Conclusion The 20 STR loci are highly polymorphic in this southern Chinese Han population,suggesting the value of this set of STR loci in forensic personal identification,paternity testing and anthropological study.

Objective To evaluate the value of PowerPlex（R）21 System (Promega) and study the genetic polymorphism of its 20 short-tandem repeat (STR) loci in southern Chinese Han population.Methods We conducted genotyping experiments using PowerPlex(R)21 System on 20 autosomal STR loci (D3S1358,D1S1656,D6S1043,D13S317,Penta E,D16S539,D18S51,D2S1338,CSF1PO,Penta D,TH01,vWA,D21S11,D7S820,D5S818,TPOX,D8S1179,D12S391,D19S433 and FGA) in 2367 unre1ated Chinese Han individuals living in South China.The allele frequencies and parameters commonly used in forensic science were statistically analyzed in these individuals and compared with the reported data of other populations.Results The PowerPlex（R） 21 System had a power of discrimination (PD) ranging from 0.7839 to 0.9852 and a power of exclusion (PE) ranging from 0.2974 to 0.8099 for the 20 loci.No significant deviation from Hardy-Weinberg expectations was found for all the loci except for D5S818.This southern Chinese Han population had significant differences in the allele frequencies from 8 ethnic groups reported in China,and showed significant differences at 8 to 20 STR foci from 5 foreign populations.The allele frequency at the locus D1S1656 in this southern Chinese Han population differed significantly from those in the 5 foreign populations and from 3 reported Han populations in Beijing,Zhejiang Province and Fujian Province of China.The neighbor-joining phylogenetictree showed clustering of all the Asian populations in one branch,while the northern Italian and Argentina populations clustered in a separate branch.This southern Chinese Han population had the nearest affinity with the Yi ethnic population in Yunnan Province of China.Conclusion The 20 STR loci are highly polymorphic in this southern Chinese Han population,suggesting the value of this set of STR loci in forensic personal identification,paternity testing and anthropological study.

Objective TodeterminethevalueofT1WIsignalratioofbilateralglobuspallidustoputamenindiagnosisofhighbilirubin relatedencephalopathyoftermneonates.Methods ThecranialMRIsignalcharacteristicsandclinicaldataof105newbornswereanalyzed retrospectively.Accordingtothetotalserumbilirubin (TSB)andclinicalsymptoms,86caseswithoutriskfactorsofterm neonates weredividedinto4groups(Ⅰ~Ⅳand3groups(A~C).TheT1WIsignalintensityofbilateralglobuspallidusandputamenwere m easured and the ratio of G/P w as calculated.T he data of each group w ere co m pared and analyzed by t test and ANOVA.R O C curve ofG/Pratiowasperformedtopredicttheprogressofdisease.Results TherewasstatisticallysignificantdifferencebetweengroupⅠandgroupⅡ,groupⅠandgroupⅢ,groupⅠandgroupⅣ,groupⅡandgroupⅢ,groupⅡandgroupⅣ(P＜0.05),whereasno differencewasfoundbetweengroupⅢandgroupⅣ (P＞0.05).Comparingthethreegroupsdividedbyclinicalsymptoms,statistically significantdifferenceswereobserved(P＜0.05).TheROCcurverevealedthatforserum TSB,thepredictiveriskofhyperbilirubinemia with1.51and1.62,thepredictiveperformanceforhighbilirubinrelatedencephalopathywith1.70and1.69.Conclusion TheT1WI signalintensityratioofG/Ppotentiallyassistsinthediagnosisofhighbilirubinrelatedencephalopathy.Combinedwithclinicalmanifestations, itcanbecomprehensivelyanalyzeddialectically,therebyincreasingtheobjectiveaccuracyofdiagnosis.

Objective To investigate the application value of slice encoding for metal artifact correction-view angle tilting(SEMAC-VAT)in chronic hip pain after total hip arthroplasty(THA).Methods A total of 22 patients who underwent TH A and required MRI reassessment for chronic hip pain were enrolled.All patients underwent coronal and axial short time inversion recovery(STIR)and SEMAC-VAT sequence scans.The prosthesis and surrounding artifact areas of STIR sequence and SEMAC-VAT sequence images were measured respectively.Likert scores were assigned to evaluate prosthesis clarity and visibility of surrounding anatomical structures.The number of abnormal lesions detected was recorded.Paired t-test and rank-sum test were used for comparisons between groups.Results Among the 22 patients,the mean prosthesis and surrounding artifact areas measured in coronal and axial STIR sequences were(73.08±11.28)cm2 and(34.36±8.47)cm2,respectively.For SEMAC-VAT sequences,the corresponding values were(44.30±8.41)cm2 and(23.08±5.85)cm2,respectively.These differences were statistically significant(t=13.942,8.659,P＜0.05).SEMAC-VAT sequences had higher Likert scores on coronal and axial prosthesis clarity and surrounding anatomical structures visibility than STIR sequences(P＜0.05).Additionally,SEMAC-VAT sequences were more effective in detecting abnormal lesions than STIR sequences(P＜0.05).Conclusion Compared to STIR sequences,SEMAC-VAT sequences significantly reduce metal artifacts and enhance image quality in the assessment of chronic hip pain after THA.This technique is advantageous in detecting more positive signs,facilitating the evaluation of hip images in patients with chronic pain after TH A,and subsequently clarifying the etiology of pain.