Objective To investigate the keratin 9 gene mutation in epidermolytic palmoplantar keratoderma (EPPK) and its relationship with clinical manifestations. Methods Three Chinese pedigrees with EPPK were studied. Polymerase chain reaction (PCR) was performed to amplify the seven exons encoded by keratin 9. Denaturing high-performance liquid chromatography (DHPLC), DNA sequencing and allele-specific PCR were used to reveal the sequence variation in the PCR products. Results An insertion-deletion mutation in the exon 1 of keratin 9 497delAinsGGCT, was revealed in all 3 EPPK families, resulting in the keratin 9 change from tyrosine166 to tryptophan and leucine (Y166delinsWL). Allele-specific PCR confirmed that the mutation was not a commonly seen polymorphism, but a novel mutation which has not been reported in The Human Intermediate Filament Mutation Database (http://www.interfil.org). Conclusions A new keratin 9 gene mutation, 497delAinsGGCT, is found in these Chinese EPPK pedigrees, which may be the genetic basis of EPPK.

OBJECTIVETo evaluate the effect of exposure to rush-mat dust on the health of workers.

METHODSA cross sectional study of 661 workers (349 men, 312 women) from 35 rush-mat plants was carried out by using occupational health investigation, questionnare and physical examination.

RESULTSThe geometric mean total dust concentration in the workshop was up to 20.00 mg/m3, and the geometric mean respirable dust concentration reached 8.22 mg/m3. The mean free SiO2 concentration of accumulated dust was 25.6%. The prevalence of radiographic small opacities profusion category > or = 1/0, according to the China Classification for pneumoconiosis (GB 5906-2000), and compared with the ILO 1980 system, was 2.57%. Even more, one man had category 2 pneumoconiosis with progressive massive fibrosis. However, the incidence of pneumoconiosis (1/0 at least) was correlated with work duration and dust concentration(r = 1.156, P < 0.001; r = 0.106, P = 0.006, respectively). Some positive correlations were found between the incidence of cough or expectoration and occupational exposure (r = 0.085, P = 0.028; r = 0.094, P = 0.016, respectively).

CONCLUSIONTo our knowledge, this is the first report of rush pneumoconiosis in China. The results have offered the possibility of a dose-response relationship between rush-mat dust and pneumoconiosis. More investigation in this area is need.

Aluminum Silicates ; Chemical Industry ; Cross-Sectional Studies ; Dust ; Female ; Humans ; Male ; Occupational Exposure ; adverse effects ; Pneumoconiosis ; etiology