Objective To investigate the application of leukoreduction filter in removal of leukocytes in platelet concentrate . Methods Platelet concentrate was prepared by using platelet‐rich plasma method .35 bags of the same type of prepared platelet concentrate were filtered by using leukoreduction filter .The changes of conventional indicators of platelet before and after filter were measured and recorded .The activating platelets indicators PAC‐1 and CD62p were detected by using flow cytometry .The platelet hypotonic shock was measured by biochemical analyzer .The platelet aggregation was measured by using platelet aggrega‐tion instrument .Results After platelet concentrate was filtered by using leukoreduction filter ,leukocyte removal rate was(98 .28 ± 0 .97)% ,platelet recovery rate was(86 .37 ± 2 .84)% .After filtration ,white blood cell count ,platelets ,red blood cells were reduced than before filtration(P<0 .05) .The differences of capacity of platelets ,mean platelet volume and pH before and after filtration were not statistically significant(P> 0 .05) .Before and after filtration ,the expression of platelet activation markers PAC‐1 and CD62p ,platelet aggregation and platelet hypotonic shock were not statistically different(P>0 .05) .Conclusion Platelet leukore‐duction filter could effectively filter leukocytes in platelet concentrate .It would not change the conventional indicators ,and not affect platelet activation ,aggregation and anti‐hypotonic shock capacity significantly .

OBJECTIVE: To determine GJB2 allelic mutant and estimate probability of hereditary hearing loss in newborn with GJB2 heterozygous mutation in Beijing. METHOD: We performed genetic testing for sequencing of GJB2 gene for searching GJB2 allelic mutant in 915 newborn who received newborn deafness gene screening (GJB2 c. 235delC, GJB2 c. 299_300delAT, GJB2 c. 176191del16, GJB2 c. 35delG) in Beijing Tongren hospital, and the mutation were classified to pathogenic mutation,undefined variant and polymorphism. RESULT: Four hundred (43.72%, 400/915) newborn were detected to carry at least one mutation allele in GJB2. 3 (0.33%, 3/915) newborn had pathogenic mutations (c. 94C>T, c. 380G>T, c. 344T>G); 62 (6.76%, 62/915) newborn carried 14 undefined variant, 36 newborn had c. 109G>A (58.06%, 36/62),13 newborn had c. 368C>A (20.97%,13/62), six (c. 268C>G, c. 282C>T, c. 294G>C, 456C>T, c. 501G>A, c. 587T>C) are novel; 335 (36.61%, 335/915) newborn were polymorphism. CONCLUSION The probability of hereditary hearing loss is 7.09% in newborn with GJB2 heterozygous mutation in Beijing. It is noteworthy that c. 109G>A, c. 368C>A occupy a high proportion.
Alleles ; Beijing ; Connexin 26 ; Connexins ; genetics ; DNA Mutational Analysis ; Deafness ; genetics ; Genetic Testing ; Heterozygote ; Humans ; Infant, Newborn ; Mutation ; Neonatal Screening ; Polymorphism, Genetic

Objective To determine the audiological characteristics in 832 deaf children with biallelic causative mutations in GJB2 ,SLC26A4 gene .Methods The 832 patients received deafness gene screening ,553 were GJB2 gene biallelic causative mutations ,279 were SLC26A4 gene biallelic causative mutations .Patients were divided into four groups according to ages of hearing loss onset :<1 ,1~3 ,3~6 ,6~12 years old ,and the audiological character-istics and prevalence of GJB2 ,SLC26A4 gene mutations at different ages of onset .Results The prevalence of GJB2 gene mutations at four groups was 37 .97% (210/553) ,38 .34% (212/553) ,16 .27% (90/553) ,7 .41% (41/553) ,re-spectively ;the prevalence of SLC26A4 gene mutations at four groups was 25 .45% (71/279) ,44 .80% (125/279) , 20 .07% (56/279) ,9 .67% (27/279) ,respectively .The difference between GJB2 and SLC26A4 gene was significant(P=0 .001) .The prevalence of profound hearing loss with GJB2 gene mutations at four groups were 66 .67% (140/210) ,61 .32% (130/212) ,47 .78% (43/90) ,41 .46% (17/41) ,respectively .The difference was significant (P=0 .004) ,while the difference in 279 patients with SLC26A4 gene mutations was not statistically significant (P= 0 . 083) .Conclusion The age of hearing loss onset in patients with biallelic causative mutations in GJB 2 or SLC26A4 gene refers to 0~3 years -old ,hearing loss in patients with GJB2 ,SLC26A4 gene mutations gives priority to pro-found .The age of hearing loss onset is smaller ,the ratio of profound hearing loss is higher .Patients with severe and profound hearing impairment should be performed the genetic testing when the age of onset under 12 .