RESUMEN
Bronchoalveolar lavage is an important animal experimental technique in the study of respiratory system and its pathological changes. It can acquire a variety of biochemical factors, inflammatory mediators and immune cells from the respiratory tract and lungs, and provides an important evaluation index and reference for animal experiment. Bronchoalveolar lavage is an effective and reliable method for the diagnosis of respiratory diseases. It has been gradually standardized and widely used in clinical practice at present, however, there is no set of standard for bronchoalveolar lavage in rats and mice. The results of bronchoalveolar lavage fluid are affected by many factors, such as the lavage fluid, suction pressure, the amount of lavage and recovery, and the retention time of lavage fluid in the lungs. Successful and efficient acquisition of lavage specimens is the key to the study and evaluation of respiratory diseases. This paper summarizes the current lavage methods commonly used by domestic and foreign researchers, and provides a reference for further research in the this field.
RESUMEN
Cystic tumour of the atrioventricular node is a rare primary cardiac tumour that can cause complete heart block and sudden death. Here, we describe a male case aged 42 years who suddenly died without a medical and family history of cardiac illnesses. After detailed macroscopic and microscopic examinations, a cystic mass was found in the atrioventricular nodal region. The small lesion was less than 1 cm in diameter, and consisted of small and large cystic spaces and tubular structures lined by flat, cuboidal or squamous epithelium. Immunohistochemical staining revealed the tumour epithelium positive for epithelial membrane antigen, carcinoembryonic antigen, antigen epitopes AE1/AE3, cytokeratins CK5/6 and CK7, but negative for calretinin, HBME-1, Wilms' tumor 1, factor VIII, chromogranin, synaptophysin or smooth muscle actin, suggesting an endodermal rather than mesothelial origin.