OBJECTIVETo investigate the changes in the number and distribution of myoepithelial cells during atrophy of the rat parotid gland.

METHODSAtrophy of the right parotid was induced by ligating the right stensen duct of rats, histological changes of parotid glands were examined by hematoxylin-eosin (HE) staining during each step of glandular atrophy at the time of 0 (control), 1, 3, 5, 7, 14, 21, 30, 60, 100, and 150 days after ligation. Immunohistochemical labelling was performed to study the changes in number and distribution of myoepithelial cells during atrophy of the rat parotid gland.

RESULTSHistological analysis showed disappearance of the acini at 5 d and gradual decrease and fibrosis of the glandular lobules accompanied by the occurrence of duct-like structures. Quantitative analysis of myoepithelial cells showed significant increase in number up to day 5 after ligation, then followed by gradual increases at a low level, at last it was followed by a rapid decrease after the total number reached the peak in 100 days. In addition, the acini and intercalated ducts were covered by myoepithelial cells ranged from the shape of spindle to stellate during the early phase of atrophy, while spindle-shaped myoepithelial cells were located at the periphery of duct-like structures in the later phase of atrophy.

CONCLUSIONMyoepithelial cells proliferated rapidly up to day 5 after ligation, then followed by gradual increase at a low level, at last it was followed by a rapid decrease after the total number reached the peak in 100 days.

Actins ; Animals ; Atrophy ; Epithelial Cells ; Ligation ; Parotid Gland ; Rats ; Regeneration ; Salivary Ducts

Objective: To assess the application of quantitative immunochemical fecal occult blood test (qFIT) in screening of gastrointestinal diseases for health check-up population. Methods: Total 19 633 health check-up subjects, who received qFIT in AiKang Guobin Physical Examination Center from January 2018 to June 2019 qFIT, were enroll in the study. The positive rate of subjects who received qFIT were analyzed. Gastrointestinal endoscopy were used to diagnose gastrointestinal lesions. The application of qFIT in screening gastrointestinal diseases, especially colorectal cancer and precancerous lesions was evaluated. Results: Total 718 (3.66%) subjects were positive for qFIT, among whom 103 (42.3%) underwent gastrointestinal endoscopic examinations. Finally, 33 (42.3%) cases of colon adenoma, 9 (11.5%) cases of peptic ulcer, and 4 (3.1%) cases of colorectal cancer were detected; and other conditions including gastroenteritis and hemorrhoids were were also diagnosed. There were 87 cases whose qFIT were negative performed colon endoscopy, 5 (5.7%) cases of colon adenoma, no colorectal cancer were detected. The mean value of qFIT for colon cancer was higher than that for polyps (3 569±1 085)μg/L vs. (823±106) μg/L, P=0.01]. The detection rate of colon polyps in qFIT positive subjects was higher than that in qFIT negative subjects [32%(33/103) vs.5.7% (5/87)], and the detective rate of colon cancer in qFIT positive subjects was higher than that in qFIT negative subjects [3.9%(4/103) vs.0(0/87)]. Conclusion Quantitative immunochemical fecal occult blood test can improve the detection rate of colorectal cancer and precancerous lesions in screening of gastrointestinal diseases.