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Hypoxia is a major environmental stressor that can damage the oxidation metabolism of crustaceans. Glutaredoxin (Grx) is a key member of the thioredoxin superfamily and plays an important role in the host's defense against oxidative stress. At present, the role of Grx in response to hypoxia in crustaceans remains unclear. In this study, the full-length cDNA of Grx3 (SpGrx3) was obtained from the mud crab Scylla paramamosain, which contains a 129-bp 5′ untranslated region, a 981-bp open reading frame, and a 1,183-bp 3′ untranslated region. The putative SpGrx3 protein contains an N-terminal thioredoxin domain and two C-terminal Grx domains. SpGrx3 was expressed in all tissues examined, with the highest expression in the anterior gills. After hypoxia, SpGrx3 expression was significantly up-regulated in the anterior gills of mud crabs. The expression of Grx2 and glutathione S-transferases was decreased, while the expression of glutathione peroxidases was increased following hypoxia when SpGrx3 was silenced in vivo. In addition, the total antioxidant capacity of SpGrx3-interfered mud crabs was significantly decreased, and the malondialdehyde content was significantly increased during hypoxia. The subcellular localization data indicated that SpGrx3 was predominantly localized in the nucleus when expressed in Drosophila Schneider 2 (S2) cells. Moreover, overexpression of SpGrx3 reduced the content of reactive oxygen species in S2 cells during hypoxia. To further investigate the transactivation mechanism of SpGrx3 during hypoxia, the promoter region of the SpGrx3 was obtained by Genome Walking and three hypoxia response elements (HREs) were predicted. Dual-luciferase reporter assay results demonstrated that SpGrx3 was likely involved in the hypoxia-inducible factor-1 (HIF-1) pathway during hypoxia, which could be mediated through HREs. The results indicated that SpGrx3 is involved in regulating the antioxidant system of mud crabs and plays a critical role in the response to hypoxia. [ABSTRACT FROM AUTHOR]

Mud crab (Scylla paramamosain) is an important economic species in China. Vibrio parahaemolyticus infection have caused a great economic loss in mud crab farming. The mechanism involved in the immune responses of mud crab to V. parahaemolyticus is unclear. In this study, the physiological and immune response to V. parahaemolyticus infection were investigated in S. paramamosain. The results showed that V. parahaemolyticus infection decreased total hemocyte counts, led to cytological damage, and caused high mortality. Transcriptome analysis showed that 1327 differentially expressed genes (DEGs), including 809 up-regulated and 518 down-regulated ones, were obtained after V. parahaemolyticus challenge. These DEGs were mainly involved in the immune response and infectious disease. Additionally, transcriptome analysis revealed that Toll, immune deficiency (IMD), and prophenoloxidase signalling pathways played essential roles in antibacterial immunity against V. parahaemolyticus infection in mud crab. • V. parahaemolyticus led to cytological damage, and caused high mortality. • 1327 DEGs were obtained after V. parahaemolyticus challenge. • Toll, IMD, and prophenoloxidase signalling pathways played important roles in response to V. parahaemolyticus infection. [ABSTRACT FROM AUTHOR]

Objective: To investigate the prevalence rate and risk factors for asthma in children from the Futian District of Shenzhen, China who were aged from 0-14 years between 2010 and 2011, and to provide scientific evidence for the prevention and treatment of childhood asthma., Methods: A multistage stratified cluster sampling survey of 7168 children aged 0-14 years from the Futian District of Shenzhen was conducted using the Third National Childhood Asthma Epidemiological Questionnaire 2010, to investigate the prevalence rate of childhood asthma. A case-control study (1∶1) and logistic regression analysis were used to investigate the risk factors for childhood asthma., Results: Of the 7168 children surveyed, 169 were diagnosed with asthma, with a total prevalence rate of 2.36%. The prevalence rate was higher in males than in females (3.06% vs 1.55%, P<0.01). Of the 169 cases, 115 (68.1%) had their first asthma attack before the age of 3 years, 95 (56.2%) had moderate attacks, 159 (94.1%) had sudden attacks, 86 (50.9%) suffered from asthma during periods of seasonal change, 97 (57.4%) had attacks before going to bed, 157 (92.9%) suffered from asthma caused by respiratory infection, and 159 (94.1%) had sneezing as the sign of oncoming attack. The case-control study (including the 169 asthma cases and 169 healthy children) and logistic regression analysis both showed that the independent risk factors for asthma in children were a personal history of drug allergy (OR=3.431, 95%CI: 1.240-9.496, P=0.018), a history of food allergy (OR=4.043, 95%CI: 1.669-9.795, P= 0.002), allergic rhinitis (OR=9.686, 95%CI: 5.137-18.263, P<0.001), and a family history of allergy (OR=4.059, 95%CI: 2.054-8.018, P<0.001)., Conclusions: The prevalence rate of asthma was 2.36% in children aged 0-14 years in the Futian District of Shenzhen between 2010 and 2011. The prevalence rate had not increased when compared with the rate in this region 10 years earlier (2.39%). The prevalence rate of childhood asthma is higher in males than in females. Personal history of drug allergy, food allergy, allergic rhinitis and a family history of allergy are the independent risk factors for childhood asthma in this region.

Objective: To analyze the clinical characteristics of plastic bronchitis associated with 2009 influenza A virus (H1N1) infection., Method: A retrospective investigation of the clinical manifestation, bronchoscopy, and the histology of the cast, clinical course and outcome of 8 children with plastic bronchitis associated with influenza A virus (H1N1) infection during winter of 2009 and 2010 was performed., Result: All 8 cases were boys, the range of age was 3 to 6 years. Five cases occurred in 2009 winter, accounting for 3.3% (5/150) of hospitalized children with influenza A (H1N1) infection; 3 cases occurred in 2010 winter, accounting for 15.8% (3/19) of hospitalized children with influenza A (H1N1) infection. Two patients had an underlying chronic disease, 1 had asthma, and the other had allergic rhinitis and atopic dermatitis. All the 8 cases had fever, cough and sputum; 2 had wheezing; 5 had respiratory distress. All 8 cases were diagnosed as influenza A virus (H1N1) infection complicated with pneumonia, of whom 5 patients had atelectasis, 2 had pneumothorax, 1 had pneumomediastinum, 1 had parapneumonic effusion, 2 patients were suspected of foreign body aspiration. Seven cases were admitted to an ICU, 5 patients developed respiratory failure, and 3 patients required mechanical ventilation. Flexible bronchoscopy and bronchial lavage was performed in all cases and showed bronchial cast. Histological examination of the bronchial cast revealed a fibrinous material containing large quantity of eosinophils, neutrophils, and lymphocytes in 7 patients, fibrinous material and necrotic material without inflammatory cells in 1 patient. After the bronchial cast was removed, all patients were improved greatly, no patients died., Conclusion: Plastic bronchitis is a life-threatening complication associated with 2009 influenza A (H1N1) virus infection in children. In children with rapid and progressive respiratory distress with lung atelectasis or consolidation on chest radiograph, plastic bronchitis should be considered. Bronchoscopic extraction of casts should be carried out early.