ABSTRACT
Objective:To investigate whether memantine hydrochloride (MEM) could promote the bactericidal effect of neutrophils against methicillin-resistant Staphylococcus aureus (MRSA) and the possible mechanism. Methods:Neutrophils were co-incubated with different concentrations of MEM and MRSA for 4 h. Then the cell lysates were collected and cultured on plate for survival bacteria counting. After co-incubation, the neutrophils were collected to detect the production of reactive oxygen species (ROS) and the release of neutrophil extracellular traps (NETs). A mouse model of MRSA infection was established, and then the mice were treated with or without MEM. Blood, spleen and kidney samples were collected from the mice for bacterial colony counting and blood procalcitonin (PCT) detection. In the 48 h survival experiment, the mice were first infected with MRSA, and then treated with MEM or PBS. The survival rates of the mice were calculated and the survival curves were drawn.Results:The number of MRSA co-cultured with neutrophils decreased significantly in the presence of MEM, and within a certain concentration range, the survival number of MRSA decreased with the increase of MEM concentration. Moreover, MEM could significantly promote the production of ROS by neutrophils and the formation of NETs. In vivo experiment showed that the concentration of PCT in mouse blood samples was lower in the MRSA+ MEM group than in the MRSA+ PBS group. The animal experiment also revealed that MEM significantly decreased the bacteria loads in mouse blood and organs and increased the 48 h survival rate after MRSA infection.Conclusions:MEM could significantly promote the bactericidal effect of neutrophils against MRSA, which might be related to the enhanced generation of ROS by neutrophils and the formation of NETs.
ABSTRACT
Objective:To investigate the technical key points and clinical effects of laparoscopic surgery using the subgastric approach for infected pancreatic necrosis (IPN).Methods:From October 2020 to October 2021, The clinical data of 6 patients with IPN after severe acute pancreatitis (SAP) undergoing laparoscopic surgery using the subgastric approach at First Hospital and Second Hospital of Hebei Medical University was retrospectively analyzed. Parameters in this report included the operation time, estimated blood loss, and the patient's vital signs, inflammatory marker CRP, and WBC before operation and postoperative 24 h, 3 d, and 1 w, and postoperative complications including pancreatic leakage, organ failure, bleeding, and abdominal infection and incision infection. Follow-up after surgery was completed in outpatient checkups and long-term complications were recorded.Results:There were 4 male and 2 female patients. The median age of the 6 patients was 50 (43.5, 56.5) years. Laparoscopic debridement surgery using the subgastric approach was successfully completed in all the patients and no reoperation was needed. The median operation time was 65 (52.5, 85) min; the median estimated blood loss was 20 (25, 37.5) ml. Median APACHEⅡ score one day before surgery was 11.5 (10.25, 12.75) and the median MCTSI score at initial admission was 8 (7, 8). The inflammatory parameters including CRP, WBC, and neutrophil count on postoperative day 3 and 1w were significantly lower than those before surgery, and all the differences were statistically significant (all P value <0.05). One patient had a postoperative pancreatic fistula and was alleviated after ERCP with pancreatic stent implantation. Another patient had a incision infection after surgery and recovered after complete surgical drainage of the abdominal wall incision. No patients had complications such as heart, lung, and kidney failure, abdominal hemorrhage and infection. During the follow-up, 5 of 6 patients had no newly-occurred diabetes, except one patient who had diabetes before the operation. None of the 6 patients had recurrent IPN. Conclusions:Laparoscopic surgery using the subgastric approach for infected IPN in lesser omental sac is safe and feasible.