Respiratory effects of biomass fuel combustion on rural fish smokers in a Nigerian fishing settlement: a case control study.

Backgroud: The aim was to study the prevalence of respiratory symptoms and assess the lung function of fish smokers in Nigeria. Methods: A case control study was done among fish smokers in Nigeria. Women aged 15 years or older (n=210) involved in fish smoking and equal number of matched controls were interviewed on respiratory symptoms and their peak expiratory flow rate (PEFR) measured. Data was analysed using chi square test, student\'s t-test and odd ratios. Results: Both groups were similar in their personal characteristics. The test group had significantly increased occurrence of sneezing (153; 72.86%), catarrh (159; 75.71%), cough (138; 65.71%) and chest pain (59; 28.10%) compared with the control group, odds ratio (OR) 2.49, 95% confidence interval CI (1.62-3.82), P < 0.001), OR 3.77,95% CI (2.44- 5.85), P < 0.001, OR 3.38, 95% CI (2.22-5.15), P < 0.001, and OR 6.45,95% CI (3.22-13.15), P < 0.001, respectively. The mean PEFR of 321±58.93 L/min among the fish smokers was significantly lower than 400±42.92 L/min among the controls (p = 0.0001). Conclusion: Fish smokers have increased risk of respiratory symptoms and reduced pulmonary function. There is a need for protective equipment and periodic evaluation.

Identification and expression analysis of two Wnt4 genes in the spotted scat ( Scatophagus argus )

Background: WNT4 is a protein that plays a crucial role in ovarian differentiation and development in mammals, with a relatively well understood function in mammalian gonadal differentiation. The role of Wnt4 in teleost fish; however, remains unclear. In the present study, cDNAs of Wnt4a and Wnt4b were cloned and characterized in the spotted scat. The expression patterns of two Wnt4 genes in the gonads at different stages of development and in fish after treatment with 17α-methyltestosterone (MT) were investigated. Results: The tissue distribution showed that Wnt4a was expressed in various tissues, including the gonads, gills, spleen, brain, and fin. Interestingly, Wnt4b not only was expressed in the gills, brain, and spleen, but also was obviously expressed in the ovary. During gonad development, Wnt4a was highly expressed in the testis at stage I and Wnt4b was mainly expressed in the ovary at stages II–III. After MT treatment, the mRNA expression of Wnt4a increased significantly up to 40 d, and the transcript level of Wnt4b decreased at 20 d. Conclusions: These results suggest that Wnt4a may be involved in gonad development and plays a role in the process of spermatogonial proliferation. Our results also demonstrate that Wnt4b is not only expressed in the nervous system, but also in the ovary and it may be involved in ovary development of the spotted scat.