Objective: To summarize the circumstances of rescue events in hospitalized patients after radiotherapy for head and neck cancer in order to provide a reference for clinical decision-making. Methods: This study was approved by the hospital's medical ethics committee. A retrospective analysis was conducted on the clinical data of 86 hospitalized patients admitted between 2015 and 2023 for oral and maxillofacial diseases following radiotherapy for head and neck cancer. Based on the occurrence of rescue events, patients were divided into a rescue group (n=20) and a non-rescue group (n=66). In addition, 20 healthy subjects matched for age and gender with the rescue group were included as a control group. First, baseline characteristics were compared between the rescue and non-rescue groups. Second, a descriptive analysis of the clinical characteristics and rescue events of the rescue group patients was performed. Third, differences in laboratory inflammatory and nutritional indicators, as well as tracheostomy status, were compared between the rescue and non-rescue groups. Fourth, Dolphin Imaging software was used to measure cone beam computed tomography images of the rescue group, non-rescue group, and control group. Upper airway parameters were measured, including the sagittal and coronal diameters of the nasopharyngeal, palatopharyngeal, glossopharyngeal, and laryngopharyngeal segments Results: ① A comparison of baseline characteristics between the rescue and non-rescue groups showed no statistically significant differences in age, gender, or body mass index, but the proportion of patients with comorbid pulmonary diseases was higher in the rescue group (P<0.05). ② In the rescue group, the primary reasons for radiotherapy were nasopharyngeal carcinoma (65%) and tongue cancer (25%). The mean age was (54.75 ± 11.59) years, with a male-to-female ratio of 3:1. The main reasons for this admission included radio-osteomyelitis in the mandible (55%) and recurrence of oral and maxillofacial tumors or new primary tumors in the oral and maxillofacial region (40%). The primary reason for rescue during hospitalization was dyspnea (55%), followed by acute massive hemorrhage (15%) and cardiac arrest (15%). Rescue events occurred mostly postoperatively (65%), with a median time of occurrence at 5 days post-operatively; 30% occurred preoperatively, and 5% occurred intraoperatively. ③ Laboratory indicators and tracheostomy status: preoperative and postoperative neutrophil counts, as well as the proportion of patients undergoing tracheostomy, were higher in the rescue group compared to the non-rescue group, while postoperative albumin levels were lower (P<0.05). ④ Upper airway measurements: the coronal and sagittal diameters of the nasopharyngeal segment and the coronal diameter of the glossopharyngeal segment were smaller in both the rescue and non-rescue groups compared to the control group (P<0.001). Conclusion The data from this study indicate that hospitalized patients experiencing rescue events after radiotherapy for head and neck cancer often have comorbid pulmonary diseases or tumor recurrence/new primary tumors, and frequently present with dyspnea. They exhibit a higher inflammatory state, poorer nutritional status, a greater need for emergency airway intervention, and share a common anatomical basis for dyspnea--upper airway narrowing. Clinical attention should be fully given to high-risk patients with these characteristics.

Objective:To investigate hypoxia location in condylar cartilage in the early growth stage of rats.Methods:40 Sprague-Dawley rats were breastfed from 1 4 d to 21 d of age.1 0 rats were sacrificed at 1 2,24,48 and 96 h respectively after initiation of normal food at 21 d of age.The rats were administered pimonidazole hydrochloride (HP-1 )at a dose of 60 mg/kg by intraperitoneal injection 2 h before sacrifice.The expression of HP-1 in the whole condylar cartilage was detected by immunohistochemical staining.Results:HP-1 was mainly expressed in the chondrocytes of the fibrous and proliferative layer of cartilage,primarily concentrated in the weight-bearing area of joint-anterior aspect of the condyle and posterior aspect of the articular eminence at all time points.The highest expres-sion was observed at 24 h after initiation of normal food (P <0.01 ).Conclusion:In the early growth stage of rats,dietary loading may directly induce hypoxia in uper layer of condylar cartilage,the hyoxia level may change with time of dietary loading.

Objective:To investigate the expression of transforming growth factor ?1(TGF-?1) in dog mandibular distraction osteogenensis (DO). Methods: Mandibular DO model was established in 12 dogs and nonunion model in another 12 dogs, 4 dogs were used as the no-treatment control. Tissue samples were obtained 6 d,2 and 8 weeks after operation respectively.Immunohistochemistry and enzyme-linked immunosorbent assay (ELISA) were used to determine the expressions of TGF-?1 in the samples.Results: TGF-?1 (ng/g) in control group was 1394.3?20.1,6 d after operation that in DO and nonunion groups was 1928.5?33.5(vs control,P