Objective To investigate the expressions of activating transcription factor 3 (ATF3) and ATF4, and their effects on γ-glutamylcysteine synthetase (γ-GCS) in lung tissues of patients with chronic obstructive pulmonary disease (COPD). Methods Non-cancerous lung tissue specimens ( 5 cm or above away from tumor) were collected from 40 lung cancer patients who underwent pulmonary lobectomy between December 2008 and December 2009. The patients were divided into a COPD group and a control group according to whether they were complicated with COPD. The clinical data were collected including the history in detail, physical examination, chest X-ray or lung CT, and pulmonary function test. The mRNA and protein expressions of ATF3, ATF4, and heavy subunit of γ-GCS (γ-GCS-HS) in lung tissues were detected by in situ hybridization and immunohistochemistry. At the same time, the interaction between ATF3, ATF4 and γ-GCS-HS protein was investigated by co-immunoprecipitation method. The correlation of ATF3 and ATF4 with γ-GCS-HS was analyzed. Results The mRNA and protein expressions of ATF3, ATF4 and γ-GCS-HS in lung tissues of the COPD group were strongly positive, and significantly higher than those in the control group (P＜0.01). The co-immunoprecipitation showed that ATF3 and ATF4 antibodies could cross the clear protein bands in the immune precipitation captured by γ-GCS-HS, and the intensity in the COPD group was significantly enhanced than that in the control group (P＜0.01). Correlation analysis showed that the protein expressions of ATF3 and ATF4 were significantly positively correlated with the mRNA and protein expression of γ-GCS-HS (allP＜0.01). The protein expressions of ATF3, ATF4 and γ-GCS-HS in lung tissues were positively correlated with FEV1%pred and FEV/FVC (P＜0.01). Conclusions Oxidative stress induces overexpression of ATF3 and ATF4 which may paly role in the pathogenesis of COPD. ATF3 and ATF4 may play antioxidative effect by affecting the mRNA and protein expression of γ-GCS.
ObjectiveTo study SCN1A gene mutations and their inheritance in patients with Dravet syndrome (DS), and to analyze the phenotypes of their family members. MethodsGenomic DNA was extracted from peripheral blood samples from DS patients and their parents. SCN1A gene mutations were screened using PCR-DNA sequencing and multiplex ligation-dependent probe amplification (MLPA). Results547 DS patients were collected, SCN1A gene mutations were identified in 379 patients (69.3%), which included 179 missense mutations (47.2%), 78 nonsense mutations (20.6%), 77 frameshift mutations (20.3%), 37 splice site mutations (9.8%), and 8 cases with SCN1A gene fragment deletions or duplications (2.1%). Of 379 DS patients, the parents of 354 DS patients were further analyzed, the de novo mutations accounted for 92.9%, inherited mutations accounted for 7.1%, and in 5 of the latter families, the SCN1A-positive parent carried a somatic mutations mosaicism. For the 25 parents carrying SCN1A mutations, 1 had DS, 11 had febrile seizures plus, 9 had febrile seizures, whilst 4 were normal. ConclusionsThe mutation rate of SCN1A in DS patients is high. Most mutations are of missense and truncation mutations (including nonsense mutation and frameshift mutation). Only a few patients have carried fragment deletions or duplications. Most SCN1A mutations are de novo, only a few are inherited from the parents. SCN1A mutations carried by the parents can be in the form of mosaicism. The phenotypes of parents with SCN1A mutations can be severe, mild or normal, and a mosaic transmitting parent always shows mild or normal.