Peri-implantitis is a pathological condition involving tissues around dental implants that are characterized by inflammation of the peri-implant mucosa and progressive loss of supporting bone. We found that the antimicrobial peptide KR-12-3 (KRIVKWIKKFLR) derived from LL-37 had antibacterial properties against Streptococcus gordonii. The purpose of this study was to evaluate its antibacterial and anti-inflammatory activities and its underlying mechanisms. We evaluated the antibacterial activities of antimicrobial peptides in planktonic and biofilm states by measuring their minimum inhibitory concentration, minimum bactericidal concentration, and biofilm susceptibility. The effects of antimicrobial peptides on the production of IL-6 and IL-8 in LPS-stimulated RAW264.7 cells were detected by enzyme-linked immunosorbent assay and other experiments, and their toxicity to MC3T3-E1 cells was also studied. While maintaining low cytotoxicity, KR-12-3 exhibited growth inhibitory effects on S. gordonii in planktonic and biofilm states. Lower concentrations of KR-12-3 treatment reduced the production of inflammatory cytokines in LPS-stimulated RAW264.8 cells. The mechanisms underlying the inhibition of biofilm formation and anti-inflammatory effects have been associated with the low expression of related genes. KR-12-3 may be used to develop an antibacterial, anti-infective, and anti-inflammatory drugs for peri-implantitis.
1 September 2018 in International Journal of Nanomedicine
Background: Prevention of bacterial colonization remains a major challenge in the field of oral implant devices. Chimeric peptides with binding, antimicrobial, and osteogenesis motifs may provide a promising alternative for the inhibition of biofilm formation on titanium (Ti) surfaces. Methods: In this study, chimeric peptides were designed by connecting an antimicrobial sequence from human β-defensin-3 with a Ti-binding sequence and arginine-glycine-aspartic acid using a glycine-glycine-glycine linker. Binding to the Ti substrate and antimicrobial properties against streptococci were evaluated. Significant improvement in reduction of bacterial colonization onto the Ti surface was observed, with or without the presence of saliva or serum. The MC3T3-E1 cells grew well on the modified Ti surfaces compared with the control group. Results: The data showed that the three peptide functional motifs maintained their respective functions, and that the antibiofilm mechanism of the chimeric peptide was via suppression of sspA and sspB gene expression. Conclusion: These results indicated that the endogenous peptide fragments engineered on the Ti surface could provide an environmentally friendly approach for improving the biocompatibility of oral implants.
Background: The development of minimally invasive surgery has initiated many changes in the surgical treatment of esophageal cancer (EC) patients. The aim of this study was to compare the short-term outcomes of robotic-assisted minimally invasive esophagectomy (RAMIE), video-assisted minimally invasive esophagectomy (VAMIE), and open esophagectomy (OE). Methods: Our study included patients who had undergone McKeown esophagectomy at Tianjin Medical University Cancer Institute and Hospital between January 2016 and December 2018. We analyzed clinical baseline data, as well as perioperative and pathological outcomes. Results: A total of 312 cases met the inclusion criteria (OE: 77, VAMIE: 144, RAMIE: 91). The OE group had a greater number of late-stage patients as well as those who received the neo-adjuvant therapy, compared with the other two groups (P=0.001). The procedure time in the OE group was also shorter by approximately 20 minutes (P=0.021). Total blood loss was significantly lower in the two MIE groups (P=0.004) than in the OE group. There were no differences in the total number of dissected lymph nodes between the three groups (OE: 24.09±10.77, VAMIE: 23.07±10.18, RAMIE: 22.84±8.37, P=0.680). Both the lymph node number (P=0.155) and achievement rate (P=0.190) in the right recurrent laryngeal nerve (RLN) area were comparable between the three groups. However, in the left RLN area, minimally invasive approaches resulted in a higher number of harvested lymph nodes (P=0.032) and greater achievement rate (P=0.018). Neither MIE procedure increased the incidence of postoperative complications. Conclusions: Minimally invasive surgery could guarantee the quality of bilateral RLN lymphadenectomy without increasing postoperative complications, especially in RAMIE patients. The rational choice of different surgical approaches would improve both safety and oncological outcomes for patients.
Background: In recent years, diagnosis of early squamous cell carcinoma of the esophagus has been increasingly emphasized. The application of endoscopic submucosal dissection (ESD) has enabled safe resection of esophageal lesions. Minimally invasive esophagectomy (MIE) is also safe and feasible for early stages of the cancer. This study aimed to compare the therapeutic effects of early esophageal carcinoma treatment, and find the best predictive factor for the selection of treatment for T1a patients.Methods: We performed a retrospective study of early‐stage patients admitted to Tianjin Medical University Cancer Institute and Hospital between January 2015 and December 2018. A total of 128 patients underwent MIE, while 78 patients underwent ESD. The depth of the tumor invasion, lymph node metastasis, and complications were compared between the two groups.Results: In the ESD group, 76.92% of the patients were stage T1a, while 34.38% in the MIE group were stage T1a. The lymph node metastasis rate was 16.41% in the MIE group (6.98% in T1a stage), which related to tumor differentiation, tumor length (≥37.5 mm), depth of invasion, and angiolymphatic invasion. However, the R0 resection rate was only 73.08% in the ESD group. Comprehensive analysis of all T1 patients in the two groups revealed that the positive margin was related to tumor differentiation, tumor width (≥13.5 mm), and depth of invasion (≥3.25 mm).Conclusion: For early‐stage cases, lymph node metastasis and positive margins are risk factors affecting long‐term survival. Efficient predictive factors mentioned in our study would provide a proper indication for treatment strategy selection.
21 December 2024 in Colloids and Surfaces B: Biointerfaces
Periodontitis is an inflammatory and destructive disease caused by dental plaque, which can result in the immune microenvironment disorders and loss of periodontal support tissue. In order to promote the restoration of local microenvironment stability, a functional biomaterial Gelatin methacryloyl @MP196/exos based on characteristics of disease occurrence is designed. Transmission electron microscopy, nanosight particle tracking analysis and western blot analysis were applied to prove the presence of exos in GelMA@MP196/exos. The swelling and degradation rates of GelMA@MP196/exos were evaluated. Cell proliferation, antibacterial ability and cellular uptake and intracellular internalization of exos were assessed in the study. Efferocytosis and M2 polarization of macrophages was estimated and the effects of GelMA@MP196/exos were proved in vivo. GelMA@MP196/exos upregulated the expression of genes and proteins related to neutrophil apoptosis and promoted neutrophil apoptosis, macrophage M2 polarization, and efferocytosis. Furthermore, GelMA@MP196/exos exhibited significant antibacterial activity against Streptococcus gordonii, Fusobacterium nucleatum, and Porphyromonas gingivalis. GelMA@MP196/exos alleviated periodontitis and reduced alveolar bone loss in vivo in rat models. GelMA@MP196/exos can serve as a potential strategy for the treatment of periodontitis. The main aim of periodontal therapy is to remove dental plaque and eliminate inflammation. However, some patients with low plaque scores and insufficient neutrophil clearance, resulting in poor responsiveness to periodontal therapy. Under the circumstances, local Application of drug that regulate the immune microenvironment had significance in controlling the progression of inflammation.