Effects of sequential treatment with intermittent parathyroid hormone and zoledronic acid on particle-induced implant loosening: Evidence from a rat model.

Particle-induced implant loosening is a major challenge to long-term survival of joint prostheses. Administration of intermittent parathyroid hormone (PTH) has shown potential in the treatment of cases of early-stage periprosthetic osteolysis, while sequential administration of intermittent PTH (iPTH) and bisphosphonates (Bps) has achieved significant effects on treatment of postmenopausal osteoporosis. The objective of this study was to determine whether sequential treatment could preserve bone mass and implant fixation during a pathological course of peri-implant osteolysis in a rat model. Ninety male Sprague Dawley rats were randomly divided into nine groups, four of which were used for confirmation of establishment of the peri-implant osteolysis model at two time points, while the other five were used to determine the efficiency of the sequential treatment on peri-implant osteolysis. Implant fixation and peri-implant bone mass were evaluated using biomechanical testing, micro-CT analysis, and histology at 6 and 12 weeks postoperative. The biomechanical test demonstrated that the maximum loading force during a push-out test was significantly elevated in the sequential treatment group compared to the osteolysis group and iPTH withdrawal group at 12 weeks. Peri-implant bone morphology also indicated a robust increase in bone volume in the sequential treatment group. Sequential administration of iPTH and Bps was effective in preventing experimental peri-implant osteolysis, resulting in improved implant fixation and increased peri-implant bone volume. Clinical significance: The innovative application of sequential treatment in peri-implant osteolysis could be used clinically to improve the prognosis of patients with early-stage periprosthetic osteolysis. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:1489-1497, 2019.

[Study on effect of sho-saiko-to compound on growth of nasopharyngeal carcinoma cells in CNE-bearing nude mice].

OBJECTIVE: To investigate the role of sho-saiko-to compound (SSTC) on the growth of the well-differentiated squamous cell line 1 of nasopharyngeal carcinoma (CNE-1) and well-differentiated CNE-2 in tumor-bearing nude mouse, and try to supply scientific data for its clinical development. METHOD: SSTC were prepared by concentration gradients, and the effect of SSTC on the growth and proliferation of the CNE-1 and CNE-2 were investigated by MT assay and soft-agar colony formation test. After setting up the subcutaneous tumor-bearing nude mouse model at the right lower back (0.2 mL CNE-2 cell suspension, 5 x 10(5)/mL), we randomly divided forty mice into 5 groups and gave high, middle and low concentration groups of SSTC (0.5, 0.25, 0.125 g X mL(-1) by intragastric administration. Positive and negative groups were set up for comparison. After constant administration for 15 days, the volume and weight of the tumor were measured for inhibition rate, so as to investigate the role of SSTC on the CNE-2 bearing tumor. RESULT: In vitro, compared with negative control, SSTC at different gradient concentrations were cultured with the CNE-1 and CNE-2 for 24 h, 48 h and 72 h. It showed that the growth and proliferation of both cell lines were inhibited to some extent. The inhibition rate was increased as the concentration and culture time increasing. Both MTT assay and soft-agar colony formation test showed that the 50% inhibiting concentration (IC50) was about 2.5 g X L(-1). In vivo, compared with negative control, the SSTC could slow down the tumor growth in the SSTC treated groups. The tumor growth of the negative control group (0.76 +/- 0.28) g, (962.88 +/- 245.96) mm3 and the low concentration group of SSTC (0.88 +/- 0.40) g, (1239.66 +/- 421.93) mm3 were obviously faster than those of the high, middle concentration group of SSTC (0.22 +/- 0.14) g, (239.31 +/- 137.07) mm3; (0.20 +/- 0.16) g, (263.42 +/- 166.57) mm3 and CTX positive control group (0.20 +/- 0.10) g, (246.72 +/- 194.6) mm3 (P<0.05). CONCLUSION: SSTC could efficiently inhibit the growth and proliferation of CNE-1 and CNE-2 in vitro, and slow down the tumor growth of the CNE-2 bearing nude mice. It may be a new compound of Chinese medicine for nasopharyngeal carcinoma therapy.

Anti-HCV activities of selective polyunsaturated fatty acids.

HCV infection can lead to chronic infectious hepatitis disease with serious sequelae. Interferon-alpha, or its PEGylated form, plus ribavirin is the only treatment option to combat HCV. Alternative and more effective therapy is needed due to the severe side effects and unsatisfactory curing rate of the current therapy. In this study, we found that several polyunsaturated fatty acids (PUFAs) including arachidonic acid (AA), docosahexaenoic acid (DHA), and eicosapentaenoic acid (EPA) are able to exert anti-HCV activities using an HCV subgenomic RNA replicon system. The EC(50) (50% effective concentration to inhibit HCV replication) of AA was 4microM that falls in the range of physiologically relevant concentration. At 100microM, alpha-linolenic acid, gamma-linolenic, and linoleic acid only reduced HCV RNA levels slightly and saturated fatty acids including oleic acid, myristic acid, palmitic acid, and steric acid had no inhibitory activities toward HCV replication. When AA was combined with IFN-alpha, strong synergistic anti-HCV effect was observed as revealed by an isobologram analysis. It will be important to determine whether PUFAs can provide synergistic antiviral effects when given as food supplements during IFN-based anti-HCV therapy. Further elucidation of the exact anti-HCV mechanism caused by AA, DHA, and EPA may lead to the development of agents with potent activity against HCV or related viruses.