Study on relationship between indoor radon concentration and air exchange rate for new residential buildings / 中华放射医学与防护杂志

Objective To investigate the relationship between indoor radon concentration and air exchange rate for new residential building.Methods The indoor radon concentration and air exchange rate were measured in two new roughcast houses in Guangzhou and Hefei,respectively.The radon concentration was measured using radon instrument.The air exchange rate was measured by using tracer gas dilution method.Results The indoor radon concentrations measured in Guanzhou for two bedrooms in a 48-hour closed condition were 106 and 115 Bq/m3,the range of 17-181 and 6-224 Bq/m3.Air exchange rates were 0.16/h and 0.21/h.In Hefei,the twice measured values for one bedroom were 148 and 186 Bq/m3,the range of 8-224 and 14-290 Bq/m3,and air exchange rates were 0.14/h and 0.12/h.The indoor radon concentration exponentially decreased with the increase of air exchange rates.Conclusions Attention should be paid to the indoor radon pollution issue that may arise in new residential buildings of energy-saving design due to low air exchange rate.

Follicular occlusion triad in a family: a clinical survey and mutational analysis / 中华皮肤科杂志

Objective To observe the clinical features and to identify γ-secretase gene mutations in a Chinese family with follicular occlusion triad (FOT).Methods Clinical evaluation was carried out in a family with FOT through field investigation.Peripheral blood samples were obtained from the family members and 100 unrelated healthy controls.DNA was extracted from the blood samples,and PCR was performed to amplify all the coding regions of PSEN1,PSENEN and NCSTN genes followed by DNA sequencing and comparative analysis.Results There were 14 members over 3 generations in this family,of whom,6 (4 males and 2 females) were affected by FOT.FOT was inherited in an autosomal dominant manner in this family.Clinical manifestations varied greatly among the 4 surviving affected members.DNA sequencing revealed a novel missense mutation,c.647A ＞ C (p.Q216P),in the exon 6 of NCSTN gene in the proband,which was cosegregated perfectly with affected,but not with unaffected,members in the family.The mutation was not found in any of the unrelated controls and had not been registered in the single nucleotide polymorphism (SNP) database in NCBI.Conclusions There is a novel heterozygous missense mutation,c.647A＞C in the exon 6 of NCSTN gene,which may be the molecular basis of pathogenesis of FOT in this family.