Photoactive Poly-L-Lysine gel with resveratrol-magnesium metal polyphenol network: A promising strategy for preventing tracheal anastomotic complications following surgery.

Postoperative complications at the anastomosis site following tracheal resection are a prevalent and substantial concern. However, most existing solutions primarily focus on managing symptoms, with limited attention given to proactively preventing the underlying pathological processes. To address this challenge, we conducted a drug screening focusing on clinically-relevant polyphenolic compounds, given the growing interest in polyphenolic compounds for their potential role in tissue repair during wound healing. This screening led to the identification of resveratrol as the most promising candidate for mitigating tracheal complications, as it exhibited the most significant efficacy in enhancing the expression of vascular endothelial growth factor (VEGF) while concurrently suppressing the pivotal fibrosis factor: transforming growth factor-beta 1 (TGF-ß1), showcasing its robust potential in addressing these issues. Building upon this discovery, we further developed an innovative photosensitive poly-L-lysine gel integrated with a resveratrol-magnesium metal polyphenol network (MPN), named Res-Mg/PL-MA. This design allows for the enables sustained release of resveratrol and synergistically enhances the expression of VEGF and also promotes resistance to tensile forces, aided by magnesium ions, in an anastomotic tracheal fistula animal models. Moreover, the combination of resveratrol and poly-L-lysine hydrogel effectively inhibits bacteria, reduces local expression of key inflammatory factors, and induces polarization of macrophages toward an anti-inflammatory phenotype, as well as inhibits TGF-ß1, consequently decreasing collagen production levels in an animal model of post-tracheal resection. In summary, our novel Res-Mg/PL-MA hydrogel, through antibacterial, anti-inflammatory, and pro-vascularization mechanisms, effectively prevents complications at tracheal anastomosis, offering significant promise for translational applications in patients undergoing tracheal surgeries.

A quasi-experimental study of fresh oxygen flow on patients' oxygen reserve during mask-assisted ventilation under general anesthesia induction.

Background: To compare the effect of different amounts of fresh oxygen flow on oxygen reserve in patients undergoing general anesthesia. Methods: Seventy-two patients were enrolled in this quasi-experimental study. Patients were randomly divided into experimental groups with a fresh oxygen flow of 1 L/min, 2 L/min, 4 L/min, and 8 L/min (denoted as G1, G2, G3, and G4, respectively) for 2 min of mask-assisted ventilation. Safe apnea time (SAT) was the primary endpoint; SAT was defined as the time from the cessation of ventilation to the time the patient's pulse oxygen saturation (SpO2) decreased to 90%. Ventilation indicators such as end-tidal oxygen concentration (EtO2), end-tidal carbon dioxide partial pressure (EtCO2), SpO2, and carbon dioxide (CO2) elimination amount, during mask-assisted ventilation, were the secondary endpoints. Results: The SAT of G1, G2, G3, and G4 were 305.1 ± 97.0 s, 315 ± 112.5 s, 381.3 ± 118.6 s, and 359 ± 104.4 s, respectively (p > 0.05). The EtO2 after 2 min of mask-assisted ventilation in groups G1, G2, G3, and G4 were 69.7 ± 8.8%, 75.2 ± 5.0%, 82.5 ± 3.3%, and 86.8 ± 1.5%, respectively (p < 0.05). Also, there was a moderate positive correlation between the fresh oxygen flow and EtO2 (correlation coefficient r = 0.52, 95% CI 0.31-0.67, p < 0.0001). The CO2 elimination in the G1 and G2 groups was greater than that in the G4 group (p < 0.05). There was no significant difference in other indicators among the groups (all p > 0.05). Conclusion: The amount of fresh oxygen flow during mask-assisted ventilation was positively correlated with EtO2. Also, even though there was no significant difference, the patients' oxygen reserves increased with the increase in fresh oxygen flow.

The value of high-flow nasal cannula oxygen therapy in treating novel coronavirus pneumonia.

OBJECTIVE: This study aimed to investigate the value of high-flow nasal cannula (HNFC) oxygen therapy in treating patients with severe novel coronavirus pneumonia (COVID-19). METHODS: The clinical data of 22 patients with severe COVID-19 were collected. The heart rate (HR), respiratory rate (RR) and oxygenation index (PO2 /FiO2 ) at 0, 6, 24 and 72 hours after treatment were compared between the HFNC oxygen therapy group and the conventional oxygen therapy (COT) group. In addition, the white blood cell (WBC) count, lymphocyte (L) count, C-reactive protein (CRP) and procalcitonin (PCT) were compared before and at 72 hours after oxygen therapy treatment. RESULTS: The differences at 0 hours between the two groups were not statistically significant. Compared with COT group,in the HFNC oxygen therapy group, HR, RR and PaO2 /FiO2 were better at 6 hours after treatment, PaO2 /FiO2 was better at 24 and 72 hours. After 72 hours, L and CRP had improved in the HFNC oxygen therapy group compared with the COT group, but the differences in WBC and PCT were not statistically significant. The length of stay in the intensive care unit (ICU) and the total length of hospitalization was shorter in the HFNC oxygen therapy group than in the COT group. CONCLUSION: Compared with COT, early application of HFNC oxygen therapy in patients with severe COVID-19 can improve oxygenation and RR, and HFNC oxygen therapy can improve the infection indexes of patients and reduce the length of stay in the ICU of patients. Therefore, it has high clinical application value.

Expression of cyclooxygenase-2 and inducible nitric oxide synthase correlates with tumor angiogenesis in endometrial carcinoma.

The present study evaluated the significance of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) in 30 patients with endometrial carcinoma and the relationship of those molecular markers to tumor characteristics and microvessel density (MVD). Immunohistochemical expression of COX-2, iNOS, and CD34 was analyzed on paraffin-embedded tissue sections. The COX-2 and iNOS positive rates were 66.7% and 73.3%, respectively. The level of COX-2 expression was higher in grade II tumors than in grade III tumors (p < 0.05). The percentage of iNOS positivity was higher in patients with deep myometrial invasion than in patients without or less than 50% myometrial invasion (p < 0.05). There was significant correlation between positive COX-2 and positive iNOS expression (r = 0.601, p < 0.001). Both COX-2 and iNOS were significantly correlated with MVD (r = 0.02 p < 0.05; r = 0.599 p < 0.0001, respectively). The present findings suggest that combined expression of COX-2 and iNOS may play an important role in development and invasion of endometrial cancer and that this could be partially attributable to modulation of angiogenesis by COX-2 and iNOS.