Male kunming mice

Kunming male mice (25 g) were purchased from Beijing Vital River Laboratory Animal Technology (Beijing, China). Experimental mice were randomized to cages of 6 per group for this experiment. The mice were divided into three groups, including Control group (0.5% CMC-Na), PHT427 (L) (500 mg/kg in 0.5% CMC-Na), and PHT427 (H) (1,000 mg/kg in 0.5% CMC-Na). Mice administered via gastric gavage and closely monitored over 72 h. The number of surviving mice was recorded. All animal experimental procedures were performed under the regulations of the Institutional Animal Care and Use Committee of the Institute of Medicinal Biotechnology.

Male ICR mice weighing 20–24 g and male Kunming mice weighing 12–16 g were both purchased from Vital River Laboratory Animal Technology (Beijing, China) and housed in a constant environment with a temperature from 22 °C to 24 °C and humidity from 40% to 60%. The light/dark cycle was switched every 12 h. Free access to food and water was allowed at all times.

Male Kunming mice, weighing 30 ± 2 g, were purchased from the Beijing Vital River Laboratory Animal Technology Co., Ltd. (Beijing, China). Animals were housed in an environmentally controlled breeding room for 1 week prior to the start of the experiments and provided with standard laboratory food and water.

Male Kunming mice (6‐7 weeks old, 30‐32 g, Beijing Vital River Laboratory Animal Technology Co., Ltd.) were housed under the following standard conditions before initiation of the experiment: temperature (23 ± 1°C), humidity (45%‐55%), and photoperiod (12 h/12 h light/dark cycle), and free access to food and water. Animal care and use guidelines for Animal Experimentation were followed. The experiment was approved by the Medical Ethics Committee of Yantai Yuhuangding Hospital (No. 2019‐156).

Male Kunming mice (18–25 g) were obtained from the Vital River Laboratory Animal Technology Co. Ltd. (Beijing, China). All mice were freely provided with the same food and water and kept at 24 °C with 12 h light/12 h dark cycles. The mice were randomly divided into six groups (n = 6): control, model (PA 14), DEX (10 mg/kg/day), BAI (10 mg/kg/day), GNP (2.5 mg/kg/day), and the combination group (10 mg/kg/day BAI and 2.5 mg/kg/day GNP). The mice were administered with the drugs via intraperitoneal injection for one week. Following this, 10 μL of activated PA 14 strain (0.5 × 10⁷ in PBS) was administered into the nasal cavities of the mice to induce acute pulmonary infection [37 (link)]. Post 24 h, bronchoalveolar lavage fluid (BALF) was collected from the right lung for cytokine detection. Then, the lung tissues were soaked in normal saline and homogenated using an electric homogenizer, which were utilized for Western blotting. The middle lobes of the left lung were rinsed in a normal saline solution and fixed in 4% paraformaldehyde. Subsequently, lung tissue sections (embedded in paraffin) were stained using the hematoxylin and eosin stain for histomorphology or immunofluorescence.