Objective:To explore the time variations of the influence of the ultra-high dose rate irradiation (FLASH irradiation, FLASH-IR) and conventional dose rate irradiation (CONV-IR) of electron beams under different doses on the energy metabolism of triple-negative breast cancer cells MDA-MB-231.Methods:The basal metabolism of the MDA-MB-231 cells and normal breast epithelial cells MCF-10A was compared using a Seahorse XF Pro Metabolic Analyzer. Based on an irradiation platform with a thermionic cathode electron accelerator (6 MeV), the MDA-MB-231 cells were exposed to FLASH-IR (106 Gy/s) and CONV-IR (0.1 Gy/s) at 2 and 14 Gy, respectively. Meanwhile, a sham irradiation group was established under identical culture conditions. The mitochondrial metabolism and glycolytic metabolism of the cells at 4, 24, and 48 h post-irradiation were analyzed.Results:Compared to the MCF-10A cells, the MDA-MB-231 cells exhibited a greater reliance on glycolytic metabolism. Compared to those of the sham irradiation group, MDA-MB-231 cells in the 2 Gy CONV-IR group showed up-regulated ATP-linked respiration at 4, 24, and 48 h post-irradiation ( t = 2.69-3.70, P < 0.05). Their glycolytic level and glycolytic capacity were up-regulated only at 4 h post-irradiation and were down-regulated at 48 h ( t = 2.79, -4.44, P < 0.05). In contrast, there was no statistically significant difference in these indicators between the FLASH-IR and CONV-IR groups ( P > 0.05). However, the proton leak of the MDA-MB-231 cells in the FLASH-IR group was relatively down-regulated at 4 h post-irradiation and was significantly up-regulated at 24 h and 48 h post-irradiation compared with the CONV-IR group ( t = -2.45, 3.19, 6.51, P < 0.05). At 14 Gy, the MDA-MB-231 cells in the CONV-IR group showed progressively increased mitochondrial and glycolytic metabolism across all time points ( t = 2.48-12.14, P < 0.05). Notably, compared with the CONV-IR group, the MDA-MB-231 cells in the FLASH-IR group exhibited more significantly up-regulated basal respiration, ATP-linked respiration, and non-mitochondrial oxygen consumption ( t = 2.56-6.51, P < 0.05), as well as a higher glycolytic capacity at 24 h post-irradiation ( t = 2.86, P < 0.05). Conclusions:Low-dose (2 Gy) FLASH-IR induces relatively up-regulated proton leak in breast cancer cells MDA-MB-231 at 24 h post-irradiation. In contrast, under high-dose (14 Gy) FLASH-IR, the MDA-MB-231 cells show more pronounced mitochondrial metabolic stress and a higher demand for energy metabolism.

Objective:To explore the time variations of the influence of the ultra-high dose rate irradiation (FLASH irradiation, FLASH-IR) and conventional dose rate irradiation (CONV-IR) of electron beams under different doses on the energy metabolism of triple-negative breast cancer cells MDA-MB-231.Methods:The basal metabolism of the MDA-MB-231 cells and normal breast epithelial cells MCF-10A was compared using a Seahorse XF Pro Metabolic Analyzer. Based on an irradiation platform with a thermionic cathode electron accelerator (6 MeV), the MDA-MB-231 cells were exposed to FLASH-IR (106 Gy/s) and CONV-IR (0.1 Gy/s) at 2 and 14 Gy, respectively. Meanwhile, a sham irradiation group was established under identical culture conditions. The mitochondrial metabolism and glycolytic metabolism of the cells at 4, 24, and 48 h post-irradiation were analyzed.Results:Compared to the MCF-10A cells, the MDA-MB-231 cells exhibited a greater reliance on glycolytic metabolism. Compared to those of the sham irradiation group, MDA-MB-231 cells in the 2 Gy CONV-IR group showed up-regulated ATP-linked respiration at 4, 24, and 48 h post-irradiation ( t = 2.69-3.70, P < 0.05). Their glycolytic level and glycolytic capacity were up-regulated only at 4 h post-irradiation and were down-regulated at 48 h ( t = 2.79, -4.44, P < 0.05). In contrast, there was no statistically significant difference in these indicators between the FLASH-IR and CONV-IR groups ( P > 0.05). However, the proton leak of the MDA-MB-231 cells in the FLASH-IR group was relatively down-regulated at 4 h post-irradiation and was significantly up-regulated at 24 h and 48 h post-irradiation compared with the CONV-IR group ( t = -2.45, 3.19, 6.51, P < 0.05). At 14 Gy, the MDA-MB-231 cells in the CONV-IR group showed progressively increased mitochondrial and glycolytic metabolism across all time points ( t = 2.48-12.14, P < 0.05). Notably, compared with the CONV-IR group, the MDA-MB-231 cells in the FLASH-IR group exhibited more significantly up-regulated basal respiration, ATP-linked respiration, and non-mitochondrial oxygen consumption ( t = 2.56-6.51, P < 0.05), as well as a higher glycolytic capacity at 24 h post-irradiation ( t = 2.86, P < 0.05). Conclusions:Low-dose (2 Gy) FLASH-IR induces relatively up-regulated proton leak in breast cancer cells MDA-MB-231 at 24 h post-irradiation. In contrast, under high-dose (14 Gy) FLASH-IR, the MDA-MB-231 cells show more pronounced mitochondrial metabolic stress and a higher demand for energy metabolism.

ObjectiveTo explore the effect of oleanolic acid （OA） on water metabolism in mice with water-dampness retention caused by spleen deficiency and the mechanism. MethodThe 60 SPF Kunming （KM） mice were randomized into blank group （n=10） and modeling group （n=50）. Through long-term living in damp place and irregular diet， water-dampness retention caused by spleen deficiency was induced in modeling mice. Then the model mice were randomly classified into model group， natural recovery group， and low-dose， medium-dose， and high-dose OA groups. The mice in the blank group， model group， and natural recovery group were given （ig） 10 mL·kg^-1·d^-1 normal saline， and mice in the low-dose， medium-dose， and high-dose OA groups received 50， 100， 200 mg·kg^-1·d^-1 OA， respectively. The intervention lasted 7 days. Before and after modeling and administration， the general conditions of the mice were observed and body weight of mice was measured. The water content in feces and tissues was detected with the oven-drying method， and water load index and organ coefficient were measured with the weighing method. Enzyme-linked immunosorbent assay （ELISA） was employed to detect the urinary D-xylose excretion， serum gastrin （GAS）， total protein （TP）， albumin （ALB）， total cholesterol （TC）， high-density lipoprotein cholesterol （HDL-C）， low-density lipoprotein cholesterol （LDL-C）， interleukin-6 （IL-6）， antidiuretic hormone （AVP）， aquaporin 1 （AQP1） in renal medulla， and liver Na⁺-K⁺-ATPase. At the same time， OA was docked with ALB， IL-6， AQP1， and Na⁺-K⁺-ATPase. ResultCompared with the blank group， the model group showed withered hair， emaciation， laziness， bradykinesia， slow weight growth， infrequent spontaneous activities， high water content in feces and tissues， low weight loss after water loading， high coefficient of each organ （P<0.05， P<0.01）. Moreover， the model group had less urinary D-xylose excretion， lower serum levels of GAS， TP， ALB， and HDL-C， higher levels of TC， LDL-C， AVP， and IL-6， lower expression of Na⁺-K⁺-ATPase in the liver， and higher expression of AQP1 in renal medulla than the blank group （P<0.05， P<0.01）. The three OA groups demonstrated better general conditions， faster weight gain， more frequent spontaneous activities， lower water content in feces and tissues， larger weight loss after water loading， and lower coefficient of each organ than the model group （P<0.05， P<0.01）. Moreover， compared with the model group， the three OA groups had high D-xylose excretion， high serum levels of GAS， TP， ALB， and HDL-C， low serum levels of TC， LDL-C， AVP， and IL-6， high expression of Na⁺-K⁺-ATPase in liver， and low expression of AQP1 in renal medulla （P<0.05， P<0.01）. The recovery in each OA group was better than that in natural recovery group. Molecular docking results also confirmed that OA had high binding affinity with ALB， IL-6， AQP1， and Na⁺-K⁺-ATPase. ConclusionOA can alleviate the abnormal water metabolism in mice with water-dampness retention caused by spleen deficiency， which lays a basis for its potential clinical application.

Objective To determine the dose-response relationship of sufentanil blunting responses to double-lumen endotracheal intubation when combined with propofol given by target-controlled infusion (TCI) in patients with pulmonary tuberculosis.Methods One hundred patients of both sexes with pulmonary tuberculosis,of American Society of Anesthesiologists physical status Ⅰ or Ⅱ,aged 24-58 yr,with body mass index ＜30 kg/m2,with Mallampati grade Ⅰ or Ⅱ,undergoing thoracic surgery under general anesthesia,were divided into Ⅰ-Ⅴ groups (n =20 each) using a random number table.Anesthesia was induced with iv sufentanil 0.35 μg/kg (group Ⅰ),0.40 μg/kg (group Ⅱ),0.45 μg/kg (group Ⅲ),0.50 μg/kg (group Ⅳ) and 0.55 μg/kg (group Ⅴ),and propofol TCI (target plasma concentration 3.5 μg/ml) and iv vecuronium 0.15 mg/kg.The patients were endotracheally intubated and mechanically ventilated.The response to double-lumen endotracheal intubation was defined as positive when mean arterial pressure increased by＞ 20％ of the baseline value and/or heart rate ＞ 90 bpm within 5 min after intubation.The median effective dose (ED50),ED95 and 95％ confidence interval (95％ CI) of sufentanil blunting the responses to double-lumen endotracheal intubation were calculated by Probit analysis.Results The ED50 (95％ CI) and ED95 (95％ CI) of sufentanil blunting the responses to intubation were 0.411 (0.370-0.441) μg/kg and 0.635 (0.556-0.888) μg/kg,respectively,when combined with propofol given by TCI.Conclusion When combined with propofol given by TCI (target plasma concentration 3.5 μg/ml),the ED50 and ED95 of sufentanil blunting the responses to double-lumen endotracheal intubation are 0.411 and 0.635 μg/kg,respectively,in patients with pulmonary tuberculosis.