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Problem: How is the tumor necrosis factor (TNF) α-induced inhibitor of apoptosis (IAP) protein expression in endometriotic stromal cells (ESCs) involved in cell viability and signaling pathways?, Method of Study: Endometriotic stromal cells were isolated from ovarian chocolate cysts in 20 patients who underwent laparoscopic surgery. IAP protein expression and IκB phosphorylation were evaluated by Western blot analysis. Interleukin (IL)-8 protein expression and cell proliferation were assessed by ELISA., Results: Cellular IAP (cIAP)-2 protein expression in endometriotic tissue was higher than that of endometrium. TNFα markedly enhanced cIAP-2 protein expression in ESCs. Pretreatment with a nuclear factor (NF)-κB inhibitor attenuated TNFα-induced cIAP-2 expression. An antagonist of IAPs abrogated TNFα-induced cIAP-2 protein expression and showed a decrease in TNFα-induced IL-8 protein expression and BrdU incorporation in ESCs., Conclusions: TNFα and its downstream NFκB pathway have proven to be critical regulators of highly expressed cIAP-2 in ESCs. cIAP-2 may be a novel therapeutic target for endometriosis., (© 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Problem: The cytokine, interleukin-6 (IL-6), stimulates the production of human chorionic gonadotropine (hCG) in chorionic cells. The purpose of this study was to examine the role of nuclear factor-kappaB (NF-kappaB) during the induction of IL-6 by IL-1beta in human trophoblast cells., Method of Study: Reverse transcription-polymerase chain reaction was used to determine the gene expressions of IL-1, IL-1 receptor (IL-1R), IL-6R and gp130 in a human choriocarcinoma cell line, BeWo. The BeWo cells were cultured for 24 hr with IL-1beta (0-10 ng/mL), IL-1beta (10 ng/mL) together with IL-1 receptor antagonist (IL-1Ra) or NF-kappaB inhibitor, N-tocyl-l-phenylalanine chloromethyl ketone (TPCK). The concentrations of IL-6 in culture supernatants were measured by enzyme-linked immunosorbent assay., Results: The gene expressions of IL-1R, IL-6R and gp130, but not IL-1beta, were observed. The concentration of IL-6 was enhanced by IL-1beta in a dose-dependent fashion. The addition of IL-1Ra neutralized the effects of IL-1beta on IL-6 secretion. IL-1beta induced expression of phosphorylated IkappaB and the activation of NF-kappaB. The addition of TPCK reduced the IL-1beta-induced IL-6 expression. Adding IL-1beta increased beta-hCG production in a dose-dependent manner, and the addition of TPCK neutralized the effect of IL-1beta., Conclusion: IL-1beta may induce the IL-6 expression and hCG production in human BeWo cells via NF-kappaB.

To test the hypothesis that the condylar part of the retrodiscal tissue of the temporomandibular joint exhibits resistance to tensile force, we investigated its viscoelastic properties and stress-relaxation behavior under tension. Ten specimens were tested. Stress-relaxation tests were conducted from four different initial stress levels. The tissue exhibited a non-linear stress-strain relationship, which could be represented by a bilinear relation of two line segments. The stress-relaxation curves showed a marked drop in load during the initial 10 s and after 2 min the stress reached an almost steady non-zero level. This feature can be well represented by Kelvin's model. It is concluded that the condylar part of the retrodiscal tissue (a) exhibits a non-linear strain-dependent viscoelastic behavior (b), has a great capacity for energy dissipation and resistance to tensile forces, and (c) contributes to maintain the position of the disc relative to the condyle during jaw closing.

Traumatic joint injury is known to produce osteoarthritic degeneration in the temporomandibular joint (TMJ). However, little information, is available on its possible effect on the dynamic viscoelastic behavior of the disc. In the present study, impulsive compression was applied to the disc as a model for traumatic joint injury. This was tested in 32 porcine discs. Prior to a dynamic tensile test, impulsive compression with strain rates of 0.01, 0.1 and 1 s(-1) to a final strain of 30% was applied to these discs. Tensile stress was applied in the antero-posterior direction with a wide range of frequencies (0.1-100 Hz). The dynamic E-moduli increased as the loading frequency increased. The dynamic viscosity and elasticity decreased with an increase of strain rate, although the effect on viscosity was greater than on elasticity. The results suggest that strain rate and subsequent peak stress of impulsive compression affect primarily the dynamic viscosity of the disc, and that impulsive compression at high strain rates reduces the resistance of the TMJ disc to stress, resulting in permanent disc deformation and perforation.