[Comparison of three methods for establishing rat peri-implantitis model].

OBJECTIVE: To compare the efficiency and effect of establishing rat peri-implantitis model by traditional cotton thread ligation and local injection of Porphyromonas gingivalis lipopolysaccharide (LPS) around the implant, as well as the combination of the two methods. METHODS: Left side maxillary first molars of 39 male SD rats were extracted, and titanium implants were implanted after four weeks of healing. After 4 weeks of implant osseointegration, 39 rats were randomly divided into 4 groups. Cotton thread ligation (n=12), local injection of LPS around the implant (n=12), and the two methods combined (n=12) were used to induce peri-implantitis, the rest 3 rats were untreated as control group. All procedures were conducted under 5% isoflurane inhalation anesthesia. The rats were sacrificed 2 weeks and 4 weeks after induction through carbon dioxide asphyxiation method. The maxilla of the rats in the test groups were collected and marginal bone loss was observed by micro-CT. The gingival tissues around the implants were collected for further real time quantitative PCR (RT-qPCR) analysis, specifically the expression of tumor necrosis factor-alpha (TNF-α) as well as interleukin-1ß (IL-1ß). The probing depth (PD), bleeding on probing (BOP) and gingival index (GI) of each rat in the experimental group were recorded before induction of inflammation and before death. RESULTS: After 4 weeks of implantation, the osseointegration of implants were confirmed. All the three test groups showed red and swollen gums, obvious marginal bone loss around implants. After 2 weeks and 4 weeks of inflammation induction, PD, GI and BOP of the three test groups increased compared with those before induction, but only BOP was statistically significant among the three test groups (P < 0.05). At the end of 2 weeks of inflammation induction, marginal bone loss was observed at each site in the cotton thread ligation group and the combined group. At each site, the bone resorption in the combined group was greater than that in the cotton thread ligation group, but the difference was not statistically significant (P > 0.05), bone resorption was observed at some sites of some implants in LPS local injection group. At the end of 4 weeks of inflammation induction, marginal bone loss was observed at all sites in each group. The marginal bone loss in the cotton thread ligation group and the combined group was greater than that in the LPS local injection group, and the difference was statistically significant (P < 0.05). At the end of 2 weeks and 4 weeks of induction, the expression of TNF-α and IL-1ß in the test groups were higher than those in the control group (P < 0.05). CONCLUSION: Compared with local injection of LPS around the implant, cotton thread ligature and the two methods combined can induce peri-implantitis in rats better and faster.

Preliminary in vitro analysis of mechanism of cardiac microvascular endothelial barrier function.

To preliminarily clarify the mechanism of cardiac microvascular endothelial barrier function leading to heart failure, primary HMVEC-D cells were selected and cultured for amplification. The cells were infected with adenovirus vector containing the ADP-ribosylation factor 6 (Arf6) Q67L gene. Full-length and functional fragments of myeloid differentiation primary response 88 and ARF nucleotide-binding site opener genes were established and transfected into HEK293T cells. GTP-Arf6 pull-down experiment, fluorescent quantitative real-time PCR, immuno-coprecipitation, and transendothelial electrical resistance analysis were conducted. Interleukin-1ß (IL-1ß) induced increase in vascular permeability, whereas inhibitor SC514 blocked IL-1ß-induced transfer of nuclear factor-κB into the nucleus, from the cytoplasm. Increase in amount of activated Arf6 promoted reduction in transendothelial electrical resistance. In addition, SecinH3 significantly inhibited increase in vascular permeability, and the progression of heart failure was significantly relieved. Cardiac microvascular endothelial barrier function can lead to heart failure. However, IL-1ß induced increase in vascular permeability, which nullified the function of cardiac microvascular endothelial barrier. These findings are closely related to the activation of the Arf6-VE-cadherin signaling pathway.

Low miR-133a expression is a predictor of outcome in patients with esophageal squamous cell cancer.

OBJECTIVE: Identification and development of new biomarkers could be beneficial for diagnosis and prognosis of esophageal squamous cell cancer (ESCC) patients. The aim of this study was to examine the clinical significance of miR-133a expression in tissues from ESCC patients. PATIENTS AND METHODS: Quantitative real-time reverse transcriptive-PCR (qRT-PCR) was performed to examine miR-133a expression levels in 126 ESCC tissues. Survival curves were plotted using the Kaplan-Meier method and differences in survival rates were analyzed using the log-rank test. Univariate and multivariate Cox regression analyses were conducted to determine whether miR-133a was an independent predictor of survival. RESULTS: We found that the levels of miR-133a in ESCC tissues exhibited lower than that in matched normal tissues (p < 0.01). Low miR-133a expression was positively associated with T stage of ESCC (p = 0.013) and tumor length (p = 0.007). Moreover, low levels of miR-133a was associated with lower overall survival (OS) (p = 0.001) and disease-free survival (DFS) (p = 0.001). According to multivariate analysis, miR-133a level was confirmed to be an independent prognostic factor for worse survival. CONCLUSIONS: MiR-133a may represent a prognostic biomarker and therapeutic target in esophageal squamous cell cancer prognosis and treatment.

Association of cytokine gene polymorphisms with susceptibility to invasive candidiasis.

The aim of this study was to investigate the role of cytokine genes in the susceptibility to Candida infection. A total of 275 consecutive patients diagnosed with Candida infection were selected between May 2010 and May 2011, along with 305 uninfected controls. Genotyping of the IL-1ß gene polymorphisms (IL1ß) rs1143634, IL1ßrs16944, IL8 rs4073, IL10 rs1800872, and IL10 rs1800896 was carried out using a 384-well plate format on the Sequenom MassARRAY platform. Patients with invasive Candida infections were more likely to have had an immunocompromised state, hematopoietic stem cell transplantation, solid organ transplant, solid tumor, chemotherapy within the past three months, neutropenia, surgery within the past 30 days, acute renal failure, liver failure, and/or median baseline serum creatinine. Conditional logistic regression analyses found that individuals with the rs1800896 GG genotype were associated with a higher risk of invasive Candida infections than those carrying the AA genotype (odds ratio = 0.61, 95% confidence interval = 0.37-0.94). From the results of this case-control study, we suggest that the cytokine IL-10 gene rs1800896 polymorphism might play a role in the etiology of invasive Candida infections.

Vascularized dorsal digital fascial flap improves flexor tendon repairs.

We report a new method of flexor tendon repair in zone II using a standard modified Kessler technique combined with a vascularized dorsal fascial flap from the finger pedicled on a dorsal cutaneous branch of the proper digital artery, which is placed as a mechanical barrier between the flexor digitorum superficialis and profundus tendons. The functional outcomes of 14 patients (Group A) with flexor tendon repairs in zone II by this new technique were compared with those of 32 patients (Group B) with flexor tendon repairs in zone II using a standard modified Kessler technique only. Patients in Group A had a higher proportion of excellent results (on the modified Strickland system) and more movement in the distal interphalangeal joint than the patients in Group B.