Titanium-interlayer mediated hydroxyapatite coating on polyetheretherketone: a prospective study in patients with single-level cervical degenerative disc disease.

BACKGROUND: Currently, there are limited reports regarding investigation of the biological properties of polyetheretherketone (PEEK) coated with titanium (Ti) and hydroxyapatite (HA) in human. The objective of this study is to evaluate the in vivo response of the PEEK cages coated with Ti and HA versus uncoated PEEK cages after anterior cervical discectomy and fusion (ACDF) in patients with single-level cervical degenerative disc disease (CDDD). METHODS: Twenty-four patients with PEEK cages coated with Ti and HA (PEEK/Ti/HA group) were matched one-to-one with patients with uncoated PEEK cages (PEEK group) based on age, gender, and operative segment. All patients had been followed up for more than 2 years. Radiological assessments included intervertebral height (IH), C2-7 angle (C2-7a), segmental alignment (SA), and fusion rate. Clinical parameters included Visual Analogue Scale (VAS) and Japanese Orthopedic Association (JOA) scores. RESULTS: There was no statistical difference in SA, IH, and C2-7a between the two groups before and after surgery and all these parameters were restored postoperatively. The fusion rate of PEEK/Ti/HA group was significantly higher than PEEK group at 3-month post-operation (87.5% vs. 62.5%). At the last follow-up, the fusion rate of the both groups achieved 100%. The VAS and JOA scores were comparable between two groups and improved postoperatively. CONCLUSIONS: In patients with single-level ACDF, PEEK cage coated with Ti and HA provided a higher fusion rate than uncoated PEEK cage at 3-month post-operation, while both two cages could achieve solid osseous fusion at the last follow up. Compared with the uncoated PEEK cage, PEEK/Ti/HA cage yielded similar favorable segmental and overall cervical lordosis, IH, and clinical outcomes after the surgery.

Titanium interlayer-mediated hydroxyapatite-coated polyetheretherketone cage in transforaminal lumbar interbody fusion surgery.

BACKGROUND: The variance in clinical responses to polyetheretherketone (PEEK) cages with titanium (Ti) and hydroxyapatite (HA) coatings (PEEK-Ti-HA cages) is still not clear. In this study, we aimed to evaluate the radiographic and clinical outcomes of patients undergoing TLIF using PEEK-Ti-HA cages with a particular focus on fusion rate. METHODS: A prospective and nonrandomized study was conducted to compare the outcomes of PEEK-Ti-HA cages (group A, n = 32) and uncoated PEEK cages (group B, n = 32). The follow up time was at least 2 years. The radiographic assessments included the regional lordosis (RL), disc height (DH), and fusion rate. The clinical indexes included the Japanese Orthopedic Association (JOA) scores and visual analog scale (VAS) scores (back and leg). RESULTS: No significant differences were found in the pre- and postoperative RL and DH between Group A and Group B. And RL and DH, even if there were any variance initially, were restored not long after surgery in both groups. Though Group A had a significantly higher fusion rate than group B at 3 months post-surgery (93.7% vs. 75.0%), the fusion rates for the two groups reached the same level (100%) when it comes to the final follow-up. Additionally, differences of VAS and JOA scores for the two groups in general approximate. CONCLUSIONS: PEEK-Ti-HA cages, in contrast with uncoated PEEK cages, produced a better fusion rate at 3 months after single-level TLIF. The fusion rates of both groups could get 100% at the final follow-up. PEEK-Ti-HA cages could achieve similar RL, DH, JOA scores and VAS scores in comparison with uncoated PEEK cages post-surgery.

Cardioprotective activity of placental growth factor in a rat model of acute myocardial infarction: nanoparticle-based delivery versus direct myocardial injection.

BACKGROUND: To comparatively evaluate the cardioprotective activity of placental growth factor (PGF) delivered through direct injection and a nanoparticle-based system respectively and to study the underlying mechanisms in a rat model of acute myocardial infarction (AMI). METHODS: Poly lactic-co-glycolic acid (PLGA)-based PGF-carrying nanoparticles (PGF-PLGANPs) were created. The mean size and morphology of particles were analyzed with particle size analyzer and transmission electronic microscopy (TEM). Encapsulation efficiency and sustained-release dose curve were analyzed by ELISA. Sprague-Dawley rats were randomized into four groups (n = 10). While animals in the first group were left untreated as controls, those in the other 3 groups underwent surgical induction of AMI, followed by treatment with physiological saline, PGF, and PGF-PLGANPs, respectively. Cardiac function was evaluated by transthoracic echocardiography at 4 weeks after treatment. At 6 weeks, rats were sacrificed, infarction size was analyzed with Masson trichrome staining, and protein contents of TIMP-2, MT1-MMP and MMP-2 at the infarction border were determined by immunohistochemistry and western blotting analysis. RESULTS: PGF was released for at least 15 days, showing successful preparation of PGF-PLGANPs. Coronary artery ligation successfully induced AMI. Compared to physiological saline control, PGF, injected to the myocardium either as a nude molecule or in a form of nanoparticles, significantly reduced infarction size, improved cardiac function, and elevated myocardial expression of TIMP-2, MT1-MMP, and MMP-2 (P < 0.05). The effect of PGF-PLGANPs was more pronounced than that of non-encapsulated PGF (P < 0.05). CONCLUSION: Target PGF delivery to myocardium may improve cardiac function after AMI in rats. PLGA-based nanoparticles appear to be a better approach to delivery PGF. PGF exerts its cardioprotective effect at least partially through regulating metalloproteinase-mediated myocardial tissue remodeling.

Identification of a functional polymorphism within the 3'-untranslated region of denticleless E3 ubiquitin protein ligase homolog associated with survival in acral melanoma.

BACKGROUND: High expression of denticleless E3 ubiquitin protein ligase homologue (DTL) correlates with poor disease-free survival and overall survival in cutaneous melanoma, but the molecular features and clinical significance of this gene in acral melanoma (AM) remain unclear. METHODS: The expression levels of DTL were compared between AM and benign melanocytic nevi using existing Gene Expression Omnibus data and validated in fresh frozen tissues. Two candidate tag single-nucleotide polymorphisms (SNPs) in the 3'-untranslated region (3'UTR) of DTL in patients with AM were sequenced and analysed for their association with survival in a discovery cohort (n = 570), and the significant SNP was subjected to a replication cohort (n = 201). The expression of DTL was evaluated by immunohistochemistry. The microRNA interacting with rs11275300:C > G was predicted using in silico target prediction tools and validated by in vitro analysis. RESULTS: DTL was overexpressed in AM compared with benign melanocytic nevi. rs11275300:C > G was found to be significantly associated with progression-free survival and overall survival of patients with AM in both cohorts and the combined cohort. Furthermore, the DTL expression level in the patients with the rs11275300:G allele was higher than that in patients with the CC genotype. In vitro analysis demonstrated that DTL was a direct target of hsa-miR-4672, and the rs11275300:G allele interfered with the binding affinity of hsa-miR-4672 with the 3'UTR of DTL and thereby increased DTL expression. CONCLUSION: The rs11275300:G allele in the 3'UTR of DTL may lead to a poor prognosis and allele-specific increase in the expression of DTL by post-transcriptional regulation in AM.