A macroporous composite sponge with high water absorbency and active coagulation mechanism for traumatic hemostasis and anti-infection.

The development of a composite sponge with high water absorbency and active coagulation mechanism for traumatic hemostasis and anti-infection remains a challenge. Herein, we developed a composite sponge using gelation, swelling, and freeze-drying methods based on quaternized chitosan, succinimidyl-modified F127, and bioactive glass. The sponge exhibited macroporous structure, high porosity, and water absorbency. When exposed to blood, it strongly interacted with blood cells, promoting their adhesion, aggregation, and activation. Moreover, it activated the intrinsic coagulation pathway. The sponge/powder demonstrated superior hemostatic capacity to commercial gauze, gelatin sponge, Yunnan Baiyao, and chitosan hemostatic powder in rat tail amputation, liver superficial injury, liver resection, and liver semi-perforation wound models. The sponge also presented robust anti-infection activity against methicillin-resistantStaphylococcus aureusandEscherichia coli. Additionally, the sponge showed low cytotoxicity, hemolysis activity, inflammation response, and systemic toxicity, demonstrating its favorable biocompatibility.

[Research on cooperation between Streptococcus mutans and Lactobacilli in dental caries lesion].

OBJECTIVE: To analyze the count of Streptococcus mutans (S. mutans) and Lactobacilli (LB) in different groups and the cases in dental caries. To research the synergistic effect of S. mutans and LB in the process of dental caries. METHODS: 110 cases with dental caries were selected and divided according to the different degree of caries, nature and ages. To culture bacteria in the selective culture medium, then count the number of colonies. The detection rate of two kinds of bacteria in different groups, means of the bacteria count and the cariogenic cases were analyzed. RESULTS: The means of the two bacteria count increased along with the degree of caries increased (P < 0.05), and increased in the older group (P < 0.05) and the active stage (P < 0.05). The cases of two bacteria increased with the degree of caries increased (P < 0.05), and increased in the older group (P < 0.05). But there were no significant differences in evolution period and arrested caries. CONCLUSION: The pathopoiesis capability of S. mutans and LB enhanced with the extent of caries increased. In the older group, their synergism role play a lead position. In evolution period and arrested caries, S. mutans and LB were difference only in quantity and their solo cariogenic potential all enhanced in active stage, but there were not correlation on pathopoiesis capability and active or stationary phase.