Layer-by-layer assembly of peptides-decorated coaxial nanofibrous membranes with antibiofilm and visual pH sensing capability.

The countermeasure of biofilm infections leaving a challenge due to a dense antibiotic-resistant barrier formed by extracellular polymeric substances (EPS). Although antibiotic alternative methods have been developed to combat biofilms, develop effective remedies coupling with timely feedback about the therapeutic effect are still in urgent demand. To this end, we construct an intelligent coaxial electrospun nanofibrous membranes (ENMs) that integrated therapy of infections and in situ visualized diagnosis. Specifically, pH-sensitive alizarin was incorporated into polyamide 6 to subtly consist core layer and curcumin (Cur) was formulated with degradable polyglycolic acid (PGA) to composed of the shell layer. The shell layer can gradually release curcumin along with the degradation of PGA. Moreover, epsilon-poly-L-lysine (ε-PL) was deposited on coaxial ENMs via layer-by-layer self-assembly technique to disturb EPS integrity. As a result of the treatment, two different Gram-positive and Gram-negative bacteria displayed increased susceptibility to the drug hybrids. The degradation of PGA would trigger a sustained release of Cur and ε-PL, and once the core layer exposing, the acidic microenvironment of Staphylococcus aureus and Pseudomonas aeruginosa biofilm could be detected in situ by emerging visualized color change to timely feedback. Besides, the ENMs showed good biocompatibility. It paves a feasible and effective avenue for constructing a facile treatment and diagnosis platform for wound biofilm infections.

Involvement of JNK signal transduction pathway in endothelial cell apoptosis induced by intermittent high glucose / 中南大学学报(医学版)

OBJECTIVE@#To evaluate the effect of intermittent high glucose on the apoptosis of human umbilical vein endothelial cells (HUVECs) and its mechanism.@*METHODS@#Intermittent high glucose and constant high glucose were applied to HUVEC-12 for 7 days. Flow cytometer and fluorescent staining with Hoechst 33258 were used to detect apoptosis of HUVEC-12. The superoxide dismutase (SOD) activity and the content of malonaldehyde (MDA) in culture solution were detected with colorimetry, and the changes of p-JNK level were examined by Western blot.@*RESULTS@#The apoptosis rate was obviously higher in the intermittent high glucose group than that in the constant high glucose group (P < 0.05). The SOD activity was significantly lower in the intermittent high glucose group (P < 0.05), but MDA level was higher than those of constant high glucose(P < 0.05). SP600125, the inhibitor of JNK, decreased the apoptosis rate induced by intermittent high glucose (P < 0.05). Antioxidant (Vitamin C) inhibited the p-JNK, decreased the apoptosis rate (P < 0.05).@*CONCLUSION@#Intermittent high glucose is easier to worsen the proapoptotic effects on HUVECs than that of constant high glucose, which may account for the increased oxidative stress, and then activates JNK signal transduction pathway.

Changes and significance of levels of serum C-reactive protein and S-100? protein in patients with progressive cerebral infarction / 临床神经病学杂志

Objective To investigate the changes and significance of the levels of serum C-reactive protein(CRP) and S-100? protein(S-100?)in patients with progressive cerebral infarction(PCI).Methods 100 acute cerebral infarction(ACI) patients were divided into PCI group(38 cases) and non-PCI group(62 cases) according to the change of the neurological dysfunction scale score(SSS) within 7 d after onset.The levels of serum CRP and S-100? in the two groups were detected at the 1 d,3 d,7 d,14 d after onset,and the results were compared with normal controls(NC group).Results Compared with the non-PCI group,the levels of serum CRP and S-100? in the PCI group at every time points after onset were significantly increased(all P