Zika virus-induced brain malformations in chicken embryos.

BACKGROUND: Zika virus (ZIKV) was confirmed to be related to microcephaly in 2016. However, there is still a need for understanding the embryonic morphological changes induced by ZIKV and when they occur. Here, chicken embryos were chosen as experimental model of ZIKV to evaluate virus-associated morphological alterations that might take place during embryonic development. METHODS: A screening with different viral doses was conducted in embryos at HH Stage 10-12 (E1.5) as well as a follow up of the first 5 days postinfection (dpi) was performed to observe the main morphologic changes post ZIKV infection. RESULTS: ZIKV exposed embryos presented a higher prevalence of mortality and defects such as brain malformation when compared to controls. Moreover, we observed that the phenotypes become more evident at 4dpi, when the viral load quantification reaches a peak. CONCLUSIONS: We found that ZIKV exposed embryos presented a high prevalence of mortality and central nervous system (CNS) abnormalities in a dose-dependent manner. The phenotype was more evident 4 days postinfection, when the viral load quantification reached a peak.

The Effects of Passive Smoking on Laryngeal and Tracheal Mucosa in Male Wistar Rats During Growth: An Experimental Study.

Cigarettes contain toxic and carcinogenic substances. In this context, cigarette smoking, and similar activities, are associated with numerous pathologies, being considered a risk factor in up to 10% of the total number of deaths in adults. Recent evidence suggests that the exposure of children to smoking in the early days of their development causes many diseases. Using light microscopy, this study aims to analyze the possible histopathological effects of an experimental model of chronic inhalation of cigarette smoke (passive smoking) on the laryngeal and tracheal mucosa of young Wistar rats. A total of 24 young Wistar rats were studied for a period of 120 days. The animals were divided into two groups: passive smoking (n = 16) and control (n = 8). The level of exposure to cigarette smoke was evaluated from the urinary cotinine level. Although no cancerous lesions were identified, histopathological analysis in the laryngeal and tracheal mucosa of all the animals in the experimental group showed that the proportion of moderate and focal inflammation was higher in animals exposed to chronic inhalation of cigarette smoke (P = 0.041). Histopathologic analysis revealed moderate and focal inflammatory lesions in the region of the infraglottic mucosa in exposed animals, although without dysplastic or neoplastic lesions in the laryngeal and tracheal mucosa.