ABSTRACT
New, biocompatible materials with favorable antibacterial activity are highly desirable. In this work, we develop a unique conjugated polymer featuring aggregation-induced emission (AIE) for reliable bacterial eradication. Thanks to the AIE and donor-π-acceptor structure, this polymer shows a high reactive oxygen species (ROS)-generation ability compared to a low-mass model compound and the common photosensitizer Chlorin E6. Moreover, the selective binding of pathogenic microorganisms over mammalian cells was found, demonstrating its biocompatibility. The effective growth inhibition of bacteria upon polymer treatment under light irradiation was validated inâ vitro and inâ vivo. Notably, the recovery from infection after treatment with our polymer is faster than that with cefalotin. Thus, this polymer holds great promise in fighting against bacteria-related infections in practical applications.
Subject(s)
Bacterial Infections/therapy , Photochemotherapy/methods , Polymers/therapeutic use , Animals , Bacteria/drug effects , Biocompatible Materials , Cells, Cultured , Chlorophyllides , HeLa Cells , Humans , Microbial Sensitivity Tests , Photosensitizing Agents/therapeutic use , Polymers/chemical synthesis , Porphyrins/therapeutic use , Reactive Oxygen SpeciesABSTRACT
OBJECTIVE: To study the role of neuronal nitric oxide synthase (nNOS) in aged rats' hippocampal delayed neuronal death (DND) following brain ischemia. METHODS: Models of incomplete brain ischemia were induced by clipping common carotid artery. A total of 46 aged SD rats were divided into 8 groups: normal control group (Group A, n=5), sham-operation group (Group B, n=5), reperfusion 1, 6, 12, 24, 48, and 96 hours groups after brain ischemia for 30 minutes (Group C, D, E, F, G, and H, n=6/group). The expression of nNOS was examined by immunohistochemistry and neuronal ultrastructural changes were observed by the transmission electron microscopy (TEM) at different time points after reperfusion. RESULTS: Immunohistochemistry showed that nNOS expression in the hippocampal neurons was high in Group E, low expression in Group D, moderate expression in Group F and G. There was nearly no expression of nNOS in Group A, B, C, and H. Ultrastructure of hippocampal neurons was damaged more severely in reperfusion over 24 hours groups. CONCLUSIONS: Nitric oxide (NO) may be one of the important factors in inducing DND after ischemia/reperfusion.
Subject(s)
Brain Ischemia/enzymology , Hippocampus/enzymology , Nitric Oxide Synthase/metabolism , Reperfusion Injury/enzymology , Animals , Apoptosis , Female , Hippocampus/pathology , Immunohistochemistry , Male , Microscopy, Electron , Neurons/enzymology , Rats , Rats, Sprague-DawleyABSTRACT
OBJECTIVE: To investigate the differences in serum biochemistry between specific pathogen-free (SPF) and conventional aged Wistar rats. METHODS: Coulter-JT Analyzer was used to measure the values of serum biochemistry in the two grades of rats. RESULTS: The serum levels of alanine aminotransferase (ALT), total protein (TP), alkaline phosphatase (ALP), total cholesterol (TC), triglyceride (TG), blood urea nitrogen (BUN), creatinine, Fe, P, glucose, uric acid (UA), and low density lipoprotein (LDL) were very significantly different between male and female Wistar rats of either conventional or SPF grade (P<0.01), which also had significant difference in albumin, lactate dehydrogenase (LDH) and apolipoprotein B (ApoB) (P<0.05). Between male aged Wistar rats of the two grades, the differences of TP, albumin, albumin/globulin (A/G) ratio, TC, TG, blood glucose, ApoA1, ApoB, UA, high-density lipoprotein (HDL), LDL, and glutamic oxalacetic transaminase (GOT) were very significant (P<0.01), with also significant differences in ALT, Fe, Mg (P<0.05). Between the female rats of the two grades, the serum levels of ALT, TP, albumin, A/G ratio, ALP, TG, BUN, creatinine, Fe, ApoA1, APOB, HDL, LDL, and bile acids were very significantly different (P<0.01), and Mg was significantly different (P<0.05). CONCLUSION: Different microbiological profiles affect serum biochemistry of aged Wistar rats.