ABSTRACT
OBJECTIVE: To evaluate the diagnostic and therapeutic value of flexible bronchoscopy in children with necro⁃tizing pneumonia. METHODS: Clinical data of children diagnosed with necrotizing pneumonia in the Department of Pedi⁃atrics of the First Hospital of Jilin University from December 2016 to December 2017 were collected. The general clini⁃cal manifestations,laboratory examination results,chest X-ray or lung CT,flexible bronchoscope and other examinations of all the children were analyzed retrospectively. Based on the characteristics,diagnosis,treatment and prognosis,the ad⁃vantages of flexible bronchoscopy in this disease were analyzed. RESULTS: All the 32 cases were diagnosed as necrotizing pneumonia by imaging examination,with an average diagnosis time of 14.1 d. All 32 cases of children with necrotizing pneumonia received flexible bronchoscopy and alveolar lavage. The alveolar lavage in 32 cases presented turbidity mito⁃ta-like changes,which had high sensitivity in the diagnosis of necrotizing pneumonia. The average time for mitota-like changes in alveolar lavage was 6.7 days. CONCLUSION: Flexible bronchoscopy is an important method in the diagnosis and treatment of necrotizing pneumonia,and the change of alveolar lavage fluid is a sensitive index for early prediction of necrotizing pneumonia.
ABSTRACT
The aim of the present study was to observe the effect of trypsin digestion on the purity of in vitro cultured astrocytes and optimize the culture methods. The cerebral cortical tissue from newborn Sprague Dawley (SD) rats was isolated and digested with 0.25% trypsin for 20, 30, or 40 min. The obtained single cell suspension was then cultured. Once reaching confluence, the cells were shaken at a constant temperature. Then, each of 20 and 30 min groups was subdivided into two groups, the control group with normal digestion and two-time-digestion group, and the cells were passaged and purified. Through inverted phase contrast microscope and MTT assay, cell growth and proliferation were observed, respectively. Immunofluorescence for glial fibrillary acidic protein (GFAP) was used to observe the morphology of astrocytes and to assess their purity in different stages. Flow cytometric analysis was used to detect the apoptotic rates of purified astrocytes. The results showed that, the cells being digested for 20 min usually reached confluence at 9 d after seeding. When the digestion time was extended to 30 min, the cells grew faster and reached confluence at 7 d after seeding, meanwhile the morphology of astrocytes was normal, GFAP positive rate (70.2 ± 4.0)% being much higher than that of the 20 min group (P < 0.05). Compared with 20 min group, 40 min group showed higher GFAP positive rate, whereas the cell proliferation was slower, and cell injury was more obvious. After shaking at constant temperature, two times of trypsin digestion could decrease the number of contaminated cells after passage. The GFAP positive rates of two-time-digestion groups in passage 1 (P1) were higher than those of corresponding control groups, and the GFAP positive rate of 30 min + two-time-digestion group in P1 reached (98.1 ± 1.7)%, which was equivalent to that of the 20 min + control group in P3. However, the apoptotic rate showed no significant difference between these two groups. Based on above mentioned results, we conclude that 30 min + two-time of trypsin digestion effectively improves the purity of astrocytes and shortens the time of primary culture and purification, suggesting that it is a rapid and effective method to obtain astrocytes with high purity in vitro.