Objective:To analyze the changes in plasma endothelin-1 (ET-1) concentrations in the patients with acute respiratory distress syndrome (ARDS).Methods:Fourteen patients with ARDS induced by trauma, 8 males and 6 females, aged 19-80 yr, were studied. The severity of ARDS was graded according to the Berlin definition of ARDS after admission to intensive care unit (ICU). Venous blood samples were obtained on 1st, 3rd and 5th days after admission to ICU, the plasma ET-1 concentrations were measured by radioimmunoassay, the pulmonary vascular permeability index (PVPI) was determined by PiCCO technique, and multiple organ dysfunction (MOD) score and lung injury score (LIS) were assessed. Spearman correlation of plasma ET-1 concentrations with MOD score, LIS and PVPI was analyzed.Results:MOD score, LIS, PVPI and plasma ET-1 concentrations were significantly decreased in mild ARDS patients ( n=5) as compared with moderate ARDS patients ( n=9, P<0.05). The plasma ET-1 concentration was positively correlated with MOD score, LIS and PVPI ( r=0.69, 0.76, 0.62, P<0.001). Conclusions:Plasma ET-1 concentrations can reflect the pulmonary vascular permeability and even the severity of the disease in the early stage of ARDS, so it is necessary to carry out dynamic monitoring in the patients.

Objective:To evaluate the role of aryl hydrocarbon receptor (AhR) in the down-regulation of Clara cell secretory protein (CCSP) expression during endotoxin-induced lung injury in rats.Methods:Twenty-four clean-grade healthy male Sprague-Dawley rats, aged 8 weeks, weighing 200-250 g, were divided into 4 groups ( n=6 each) using a random number table method: normal control group (group C), acute lung injury (ALI) group, ALI+ AhR antagonist group, and ALI+ vehicle group. Lipopolysaccharide(LPS) 1 mg/kg was intratracheally instilled to develop the model of lung injury, while the equal volume of normal saline was given instead in group C. At 2 h before LPS injection, AhR antagonist 6, 2′, 4′-trimethoxyflavone solution 5 mg/kg (diluted to 1 ml in dimethyl sulfoxide solution) was intraperitoneally injected in ALI+ AhR antagonist group, while dimethyl sulfoxide solution 1 ml was given in ALI+ vehicle group. The rats were sacrificed under anesthesia at 48 h after LPS administration. The left lung was lavaged and the broncho-alveolar lavage fluid (BALF) was collected for determination of the concentrations of CCSP by enzyme-linked immunosorbent assay, and the expression of CCSP in the bronchial epithelium in right lung tissues was determined by immunohistochemistry. Results:Compared with group C, the expression of CCSP in the bronchial epithelium was significantly down-regulated, and the concentrations of CCSP in BALF were decreased in the other three groups ( P<0.05 or 0.01). Compared with ALI group and ALI+ vehicle group, the histopathological injury was significantly reduced, the expression of CCSP in the bronchial epithelium was up-regulated, and the concentrations of CCSP in BALF were increased in ALI+ AhR antagonist group ( P<0.01). Conclusions:AhR partially mediates the down-regulation of CCSP expression during endotoxin-induced lung injury in rats.

Objective　To investigate the imaging characteristics and main clinical manifestations of patients with respiratory and/or cardiac arrest after medullary infarction (MI).Methods　The study included patients with respiratory and/or cardiac arrest after MI,who were hospitalized in the Department of Neurology of Huanhu hospital between 2016 and 2021.The patients were divided into groups and analyzed according to the infarct location and infarct size shown by MRI-DWI,the degree of vascular stenosis shown by MRA and the main clinical manifestations.Results　The study enrolled a total of 28 patients, including 19 patients with lateral medullary infarction (LMI) and 9 patients with medial medullary infarction (MMI).For LMI patients,from head to tail,there were 4 cases with upper MI,11 cases with middle MI,and 4 cases with lower MI.On the axial plane,there were 4 cases in the middle,14 cases in the dorsal,and 1 case through the middle and dorsal.Among the 28 patients,50% were large area MI (DWI high signal≥1/3 of the total area of medulla oblongata) and medium area MI (1/4 of the total area of medulla oblongata≤DWI high signal<1/3 of the total area of medulla oblongata).Sixteen cases completed brain MRA examination,of which 12 cases were moderate and severe vascular stenosis.Among the 28 patients,16 cases were complicated with infarction in other parts,of which 9 cases were complicated with cerebellar infarction.The main clinical symptoms were dizziness and dysarthria.For the 19 LMI patients,dizziness was the main complaint in 16,dysarthria in 16,dysphagia in 10,limb weakness in 7.For the 9 MMI patients,dizziness was the main complaint in 6,dysarthria in 8,dysphagia in 3,limb weakness in 7.Conclusion　LMI is the main type of respiratory and/or cardiac arrest after MI,and it is more common in patients with dorsal medulla oblongata in the middle part.The proportion of patients with medium and large area MI is relatively high.Most patients have moderate and severe vascular stenosis and often complicated with cerebellar infarction.The main complaints were dizziness and dysarthria.LMI was more prone to dysphagia and MMI to limb weakness.

Our previous studies found that mitochondrial uncouplers induced vasodilation. Triclosan, the broad spectrum antibacterial agent, is the active ingredient in soaps and toothpastes. It was reported that triclosan induced mitochondrial uncoupling, so we aim to investigate the effects of triclosan on vascular function of rat mesenteric arteries and aorta. The isometric tension of rat mesenteric artery and thoracic aorta was recorded by multi-wire myograph system. The cytosolic [Ca], mitochondrial reactive oxygen species (mitoROS), and mitochondrial membrane potential of smooth muscle cells (A10 cells) were measured using laser scanning confocal microscopy. Triclosan treatment relaxed phenylephrine (PE)- and high K(KPSS)-induced constriction, and pre-treatment with triclosan inhibited PE- and KPSS-induced constriction of rat mesenteric arteries. In rat thoracic aorta, triclosan also relaxed PE- and KPSS-induced constriction. Triclosan induces vasorelaxation without involving Kchannel activation in smooth muscle cells of arteries. Triclosan treatment increased cytosolic [Ca], mitochondrial ROS production and depolarized mitochondrial membrane potential in A10 cells. In conclusion, triclosan induces mitochondrial uncoupling in vascular smooth muscle cells and relaxes the constricted rat mesenteric arteries and aorta of rats. The present results suggest that triclosan would indicate vasodilation effect if absorbed excessively.

During the COVID-19 epidemic, our national guidelines have suggested that surgical patients should wear a mask to decrease the potential transmission of COVID-19 in the operating room, as long as the condition allows. However, so far, there is no study to discuss the influence of wearing a mask on the ventilation and blood oxygenation status in patients of spontaneous breathing with supplementary oxygen through an anesthetic facemask. This is a before-after study in the same patient, and 10 healthy volunteers were recruited, by testing the arterial blood gas parameters at key time points before and after oxygen inhalation to evaluate the effects of two different supplementary oxygen methods ('disposable medical mask + anesthetic facemask' and 'anesthetic facemask only') on the oxygenation of subjects. Our data demonstrated whether wearing a disposable medical mask or not could effectively increase the oxygen supply of the subjects compared with the basic value before oxygen inhalation; however, compared with the group without mask, the arterial oxygen partial (PaO
COVID-19 ; Healthy Volunteers ; Humans ; Masks ; Oximetry ; Oxygen/blood*

Mitochondria are morphologically dynamic organelles which undergo fission and fusion processes. Our previous study found that arterial constriction was always accompanied by increased mitochondrial fission in smooth muscle cells, whereas inhibition of mitochondrial fission in smooth muscle cells was associated with arterial relaxation. Here, we used the typical vasorelaxants, verapamil and phentolamine, to further confirm the coupling between arterial constriction and mitochondrial fission in rat aorta. Results showed that phentolamine but not verapamil induced vasorelaxation in phenylephrine (PE)-induced rat thoracic aorta constriction. Verapamil, but not phentolamine, induced vasorelaxation in high K(KPSS)-induced rat thoracic aorta constriction. Pre-treatment with phentolamine prevented PE- but not KPSS-induced aorta constriction and pre-treatment with verapamil prevented both PE- and KPSS-induced aorta constriction. Transmission electron microscopy (TEM) results showed that verapamil but not phentolamine inhibited KPSS-induced excessive mitochondrial fission in aortic smooth muscle cells, and verapamil prevented both PE- and KPSS-induced excessive mitochondrial fission in aortic smooth muscle cells. Verapamil inhibited KPSS-induced excessive mitochondrial fission in cultured vascular smooth muscle cells (A10). These results further demonstrate that arterial relaxation is coupled to inhibition of mitochondrial fission in arterial smooth muscle cells.