OBJECTIVETo explore the impact of different warm ischemia time on structure and function of the non-heart-beating donor lung and to find out the feasibility of non-heart-beating donor in rat lung transplantation.

METHODSSixty Sprague-Dawley rats were randomly divided into 3 groups: heart-beating donor (HBD) group, non-heart-beating donor (NHBD) with 30 minutes of warm ischemia time (WIT) group and NHBD with 60 minutes of WIT group. Each group has 10 pairs (the donors and the recipients). The donor lungs of group HBD were flushed with low potassium dextran (LPD) solution at 4 degrees C after asystolia while the lungs of group NHBD-30 and group NHBD-60 remained ventilated at the room temperature for 30 and 60 minutes after asystolia and then were flushed with LPD solution. All the donor lungs remained inflated when they were stored in LPD solution at 4 degrees C for 4 hours. The recipient rat underwent left thoracotomy, and then orthotopic left lung transplantation. Followed by a right thoracotomy, the right pulmonary hilum were ligated with one-hour reperfusion and ventilation.

RESULTSAll the recipients in group HBD and group NHBD-30 survived the observation period of one hour with excellent gas exchange, whereas 4 of recipients in group NHBD-60 survived for 10 minutes after the ligation of right pulmonary hilum and 3 for 20 minutes. The pulmonary compliance, ultrastructure, energy metabolite and other markers revealed no significant differences between group HBD and group NHBD-30 (P > 0.05). But the differences between group NHBD-60 and other two groups were significant (P < 0.05).

CONCLUSIONSThe adoption of non-heart-beating donor could be a safe and effective method to expand the lung donor pool. The NHBD lung with 30 minutes of WIT may be suitable for lung transplantation in rat.

Animals ; Heart ; physiopathology ; Ischemia ; physiopathology ; Lung ; physiopathology ; ultrastructure ; Lung Transplantation ; Male ; Microscopy, Electron ; Models, Animal ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Time Factors ; Tissue Donors

OBJECTIVE: To explore the mechanism underlying the hepatoprotective effect of dihydromyricetin (DMY) against lipid accumulation in light of the lipophagy pathway and the inhibitory effect of DMY on HepG2 cell proliferation. METHODS: LO2 cells were cultured in the presence of 10% FBS for 24 h and treated with 100 μg/mL DMY, or exposed to 50% FBS for 24 h followed by treatment with 50, 100, or 200 μg/mL DMY; the cells in recovery group were cultured in 50% FBS for 24 h and then in 10% FBS for another 24 h. Oil red O staining was used to observe the accumulation of lipid droplets in the cells, and the levels of TC, TG, and LDL and activities of AST, ALT and LDH were measured. The expression of LC3 protein was detected using Western blotting. AO staining and transmission electron microscopy were used to determine the numbers of autophagolysosomes and autophagosomes, respectively. The formation of autophagosomes was observed with MDC staining, and the mRNA expression levels of LC3, ATG7, AMPK, mTOR, p62 and Beclin1 were determined with q-PCR. Flow cytometry was performed to analyze the effect of 50, 100, and 200 μg/mL DMY on cell cycle and apoptosis of HepG2 cells; DNA integrity in the treated cells was examined with cell DNA fragmentation test. RESULTS: DMY treatment and pretreatment obviously inhibited lipid accumulation and reduced the levels of TC, TG, LDL and enzyme activities of AST, ALT and LDH in LO2 cells (P < 0.05). In routinely cultured LO2 cells, DMY significantly promoted the formation of autophagosomes and autophagolysosomes and upregulated the expression of LC3 protein. DMY obviously attenuated high FBS-induced inhibition of autophagosome formation in LO2 cells, up- regulated the mRNA levels of LC3, ATG7, Beclin1 and AMPK, and downregulated p62 and mTOR mRNA levels (P < 0.05 or 0.01). In HepG2 cells, DMY caused obvious cell cycle arrest, inhibited cell proliferation, and induced late apoptosis and DNA fragmentation. CONCLUSION DMY reduces lipid accumulation in LO2 cells by regulating the AMPK/ mTOR-mediated lipophagy pathway and inhibits the proliferation of HepG2 by causing cell cycle arrest and promoting apoptosis.
AMP-Activated Protein Kinases/metabolism* ; Autophagy ; Beclin-1 ; Cell Proliferation ; Flavonols ; Hep G2 Cells ; Humans ; Lipids ; RNA, Messenger ; Signal Transduction ; TOR Serine-Threonine Kinases/metabolism*

Two-dimensional black phosphorus (BP) has unique layered structure, excellent photothermal properties, good biocompatibility and high biodegradability. In recent years, it has been found that BP has stable drug loading and light controlled sustained-release drug functions, excellent antibacterial properties and the ability to promote vascular and nerve regeneration in the medicine field, which has a broad application prospect in dentistry. This review elaborates the biological properties of two-dimensional BP and its application progress in dentistry, so as to provide new ideas for the further research and application of two-dimensional BP.
Anti-Bacterial Agents ; Dentistry ; Phosphorus