{'fraction_non_alphanumeric': 0.023331173039533377, 'fraction_numerical': 0.019442644199611146, 'mean_word_length': 5.151394422310757, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Morphological changes in canine lungs perfused with modified Euro-Collins solution.

OBJECTIVE
To investigate the structural changes in canine lungs perfused with modified Euro-Collins solution (mECS), thus providing insight into the preservation of the donor lung tissue for transplantation.


METHODS
Six dogs were anesthetized and pulmonary perfusion with mECS (4 degrees Celsius) was performed before the lungs were isolated thereafter and stored at 4 to 8 degrees Celsius for 30, 60, 120, 180, 240 min respectively, after which tissue samples of the donor lung were taken for morphological observation with both light and transmission electron microscope.


RESULTS
Immediately after reperfusion, the pulmonary tissues exhibited clear and intact structures,showing that mitochondrion swelled slightly in the alveolar epithelial cells (AECs). Mild edema occurred in the alveolar wall and the tissues around the veins at 30 min after preservation, which exacerbated to dilapidation of the alveolar wall and obvious tumefaction of the mitochondrion in the AECs at 60 min. At 180 min, rupture of alveolar wall and emergence of the alveolus was observed at 120 min, and a few pulmonary bullae were formed, the AECs (I) of which presented vacuolar changes in the cytoplasma and mitochondrion, with disappearance of the tiny villus of the AECs (II) at 240 min.


CONCLUSION
Within 4 h of preservation in mECS, the pulmonary tissues do not undergo obvious changes as signs of injury, which, however, may not be the case after longer preservation.