Inhibition of NF-κB by Pyrrolidine Dithiocarbamate Prevents the Inflammatory Response in a Ligature-Induced Peri-Implantitis Model: A Canine Study.

BACKGROUND/AIMS: The roles of toll-like receptor 4 (TLR4) and nuclear factor-kappa B (NF-κB) in peri-implantitis are unclear. Here, we used a canine model of peri-implantitis to explore the effects of inhibiting NF-κB with pyrrolidine dithiocarbamate (PDTC) on the inflammatory response in ligature-induced peri-implantitis. METHODS: After successfully establishing the peri-implantitis model, beagles were randomly assigned to normal, model or PDTC groups. ELISA tests were used to determine the levels of interleukin (IL)-1, IL-6, IL-8 and tumor necrosis factor alpha (TNF-α). Immunohistochemistry was employed to assess the expression of NF-κB p65. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was performed to determine the mRNA levels of TLR4 and NF-κB p65, and western blot analysis was used to measure the protein levels of TLR4 in periodontal tissues from each group. Periodontal ligament fibroblasts (PDLFs) were cultured and subsequently classified into PDLF normal, PDLF model, PDLF LPS, PDLF PDTC, and PDLF LPS + PDTC groups. An immunofluorescence assay was used to measure the expression level of NF-κB p65. The CCK-8 assay and flow cytometry were performed to evaluate cell proliferation and apoptosis. RESULTS: The in vitro results indicated that NF-κB p65 and TLR4 were upregulated in canine periodontal tissues, and PDTC could suppress the expression levels of NF-κB p65 and TLR4. Inflammation could increase TLR4 protein expression in canine periodontal tissue, and PDTC could inhibit the inflammation-induced increase in TLR4 protein expression. These results revealed that PDTC could reverse the LPS-induced increases in the levels of IL-1, IL-6, IL-8 and TNF-α. In vivo, the results demonstrated that PDTC inhibited the LPS-induced NF-κB p65 upregulation, and PDTC could reverse the inhibitory effect of the PDLF model + LPS on the proliferation of periodontal fibroblasts. The results also showed that in the PDLF model, LPS promoted PDLF apoptosis by inducing implant periodontitis in canines, but PDTC inhibited the PDLF apoptosis and relieved implant periodontitis in canines. CONCLUSION: Based on our results, we concluded that PDTC can inhibit the expression of NF-κB and alleviate the inflammatory response induced by LPS, thereby preventing periodontal inflammation and reducing the development of peri-implantitis.

The impact of smoking on levels of chronic periodontitis-associated biomarkers.

OBJECTIVE: To investigate the effect of smoking on the expression levels of matrix metalloproteinase (MMP)-1, MMP-9, tissue inhibitor of metalloproteinase-1 (TIMP-1), and the concentrations of TNF-α and IL-10 in patients with chronic periodontitis (ChP). METHODS: This is an ex-vivo study. Our study consisted of 78 cases, all of which were diagnosed with ChP and were selected according to the inclusion and exclusion criteria. Among these 78 cases, 38 patients were classified into the smoking group (S-ChP group), and 40 patients in the non-smoking group (NS-ChP group). The clinical periodontal parameters of all patients were recorded, including the plaque index (PLI), probing depth (PD), loss of attachment (LA) and sulcus bleeding index (SBI). Serum was collected from forearm blood to establish a Porphyromonas gingivalis (Pg) internalizing KB cell model. Enzyme-linked immunosorbent assay (ELISA) was used to determine the concentrations of MMP-1, MMP-9 and TIMP-1 in the KB cell lysis solution as well as IL-10 and TNF-α in the gingival crevicular fluid (GCF). RESULTS: Fewer Pg internalizing KB cell colonies were observed in the NS-ChP group than in the S-ChP group (P<0.01). When 400µL serum was added, there were remarkable differences in the concentrations of MMP-1 and TIMP-1 secreted from the KB cells between the S-ChP and NS-ChP groups (MMP-1: t=-21.71, P<0.01; TIMP-1: t=64.35, P<0.001). Additionally, when 800µL serum was added, there were significant differences in the concentrations of MMP-1, MMP-9 and TIMP-1 in the KB cells between the S-ChP and NS-ChP groups (MMP-1: t=-81.89, P<0.001; MMP-9: t=-15.67, P<0.001; TIMP-1: t=109.4, P<0.001). The TNF-α levels were higher, but the IL-10 levels were lower in the GCF from the ChP patients in the S-ChP group than those in the NS-ChP group (both P<0.001). CONCLUSION: The serum of S-ChP patients can enhance the concentrations of MMP-1 and MMP-9, but reduce TIMP-1 secreted from Pg internalizing KB cells. However, the concentration of TNF-α was increased and IL-10 was decreased. Abnormal concentrations of ChP-associated biomarkers may be conducive to the development and progression of ChP.

Inflammatory myofibroblastic tumors of the nasal cavity and paranasal sinus: a clinicopathologic study of 25 cases and review of the literature.

Inflammatory myofibroblastic tumor (IMT) is rare in nasal cavity and paranasal sinus. The aim of this study was to describe the clinicopathological features of sinonasal IMT and analyze the relationship between the clinicopathological features and the prognosis. A retrospective study of 25 IMT patients between 2001 and 2012 was performed. Data on clinical features, treatment, and follow-up were recorded. The histological characters were observed. Overall survival (OS) and event-free survival (EFS) were estimated using the Kaplan-Meier method. Clinically, the most common symptoms were nasal obstruction, facial pain, and toothache. Twenty patients received follow-ups 6-120 months after initial diagnosis. Fifteen (75 %) developed recurrence 1 or more times. One patient had left cervical lymph node metastasis (5 %). Five patients died of the tumor (25 %). Histologically, the IMTs composed of bland spindle cells admixed with a prominent infiltrate of plasma cells and lymphocytes and showed obvious atypia in recurrent cases. Histology with necrosis, mitosis (≥1/10 HPF), ganglion-like cells, histological pattern I or II and relapse (≥4 times) was significantly associated with poor OS and EFS. IMT of the nasal cavity and paranasal sinuses exhibits relatively bland histologic appearances, but can shows strongly aggressive behavior and relatively poor outcomes. Multiple relapse, necrosis, frequent mitosis, the presence of ganglion-like cells, and histological pattern might be associated with poor clinical outcomes.

[Clinicopathologic study of invasive fungal rhinosinusitis caused by Aspergillus and Mucorales].

OBJECTIVE: To compare the differences in clinicopathologic features of invasive fungal rhinosinusitis caused by Aspergillus and Mucorales, and to discuss the pathogenesis of tissue injury induced by these two kinds of fungi. METHODS: The clinical and pathologic features of 19 patients with invasive fungal rhinosinusitis due to Aspergillus (group A) and 16 patients with invasive fungal rhinosinusitis due to Mucorales (group M) were retrospectively reviewed. HE, PAS and GMS stains were performed on all the paraffin-embedded tissues. The diagnosis was confirmed by histologic examination and microbiological culture results. RESULTS: Amongst the group A patients, the clinical course was acute in 4 cases and chronic in 15 cases. Thirteen cases had underlying predisposing conditions, including diabetes (number = 4), malignant tumor (number = 5), history of trauma (number = 1) and radical maxillary sinus surgery (number = 3). Follow-up information was available in 13 patients. Seven of them died, 4 due to fungal encephalopathy and 3 due to underlying diseases. Amongst the group M patients, the clinical course was acute in 14 cases and chronic in 2 cases. Fourteen cases had underlying predisposing conditions, including diabetes (number = 8), malignant tumor (number = 5) and history of wisdom tooth extraction (number = 1). Follow-up information was available in 14 patients. Four of them died of fungal encephalopathy. There was significant difference in clinical onset between the two groups (P = 0.01). There was however no difference in terms of underlying predisposing conditions and disease mortality. Histologically, the microorganisms in group A patients formed fungal masses and attached to the mucosal surface, resulting in necrotic bands (11/19). Epithelioid granulomas were conspicuous but multinucleated giant cells were relatively rare. Deep-seated necrosis, granulomatous inflammation against fungal organisms (3/19) and vasculitis with thrombosis (4/19) were not common. On the other hand, large areas of geographic necrosis involving deep-seated tissue could be seen in group M patients (13/16). Isolated multinucleated giant cells were commonly seen. Granulomatous inflammation against fungal organisms were identified (16/16). Vasculitis and thrombosis were also observed (10/16). CONCLUSIONS: The invasiveness of Mucorales is remarkable; and when it causes invasive fungal rhinosinusitis, the clinical course is often acute and large areas of tissue necrosis can be seen. The invasiveness of Aspergillus in tissue is relatively mild. Granulomas are more common and the disease often runs a chronic clinical course. There is however no significant difference in long-term mortality. The pathogenesis may be related to the different components of the fungi.

Preparation of reversible colorimetric temperature nanosensors and their application in quantitative two-dimensional thermo-imaging.

Reversible colorimetric temperature nanosensors were prepared using a very simple precipitation method to encapsulate two color luminescent dyes. These nanosensors presented obvious reversible temperature response and enabled both rapid colorimetric temperature estimation using the eyes and quantitative two-dimensional thermo-imaging. Heat-exchange induced fluid motion was, for the first time, rapidly, precisely, and quantitatively imaged by just taking color pictures, and this presented good temporal and spatial resolution for studying heat-driven hydrodynamics. These nanosensors should have great application in micro/nanoscale research and also fabrication into films for macroscopic study.

[Clinicopathologic study of sinonasal inflammatory myofibroblastic tumor].

OBJECTIVE: To study the clinicopathologic features, immunophenotype and ultrastructural features of sinonasal inflammatory myofibroblastic tumors (IMT). METHODS: The clinical and histologic features of 5 cases of sinonasal IMT were reviewed. Immunohistochemical study for vimentin, MSA, SMA, calponin, h-caldesmon, desmin, ALK, fibronectin, CK, S-100 and Ki-67 was carried out. Ultrastructural examination was also performed in two of the cases. RESULTS: The patients age ranged from 28 to 62 years (mean = 43 years). The male-to-female ratio was 2:3. The clinical presentation included nasal obstruction, nasal discharge, nasal bleeding, facial pain, facial swelling, toothache and tear overflow. All of the 5 patients suffered from disease relapses; and 4 of them had recurrences for more than 5 times. One patient had lymph node metastasis and 3 patients died of the disease. Histologically, the tumor cells were arranged in interlacing fascicles and sometimes haphazard in fashion. They were spindly in shape, cytoplasm eosinophilic with mild nuclear atypia and a low mitotic activity. The intervening stroma was myxoid in appearance accompanied by lymphocyte and plasma cell infiltration, abundant blood vessels and focal collagenized areas. In 3 of the recurrent cases, the tumor cells displayed increased nuclear atypia and mitotic activity (average about 5 to 6 per 10 high-power fields), accompanied by patchy necrosis, less inflammatory cell infiltration and focal sarcomatous changes. Immunohistochemical study showed that the tumor cells were diffusely positive for vimentin. SMA, MSA, calponin and fibronectin were variably expressed. Desmin was weakly positive in 1 case. The staining for h-caldesmon, ALK, S-100 and CK was negative. The Ki-67 proliferation index increased with tumor recurrences. Electron microscopy revealed abundant rough endoplasmic reticulum and dense body formation in the cytoplasm. There were an increased amount of collagen fibers in the stroma. CONCLUSIONS: IMT rarely occurs in nasal cavity and paranasal sinuses. The tumor is prone to local invasion and recurrences, with subsequent progression to frank malignancy and distant metastasis, resulting in high mortality and poor prognosis. Complete surgical resection remains the main modality of treatment.