Five-Year Evaluation of Lifecore Restore® Implants: A Retrospective Comparison with Nobel Biocare MK II® Implants

Purpose: The purpose of this study was to compare survival rates and marginal bone resorption of the Lifecore (LC) Restore® Implant System with the benchmark Nobel Biocare (NB) MK II® Implant System.
Materials and Methods: All implants were inserted by the same surgeon and all radiological analyses were performed by the same radiologist. Two hundred ninety LC implants were analyzed radiologically after 1 year and compared with the same number of NB implants serving as a historical reference group. After 5 years, 200 LC implants could be compared with 224 NB implants. Each implant was monitored for exposed threads, as compared with the baseline registrations.
Results: No significant differences were found between the two implant systems regarding survival rates (LC 100% and NB 99.2%). Considering the findings of this study, the two implant systems compared might be regarded as clones. Nevertheless, because of dissimilar onset of threads, about 1 mm more implant-retaining bone anchorage is gained with the Lifecore Restore Implants as compared with NB MK II Implants.
Conclusions: Based on the assumption that >3 exposed NB threads correspond to >4 exposed LC threads, significantly more bone loss ( p  < .01) could be demonstrated for the NB implants after 5 years. Thus, it may be justified to consider the differences in implant design to have a decisive clinical relevance.     

Evaluation of Long–Lasting Antibacterial Properties and Cytotoxic Behavior of Functionalized Silver-Nanocellulose Composite

Materials possessing long-term antibacterial behavior and high cytotoxicity are of extreme interest in several applications, from biomedical devices to food packaging. Furthermore, for the safeguard of the human health and the environment, it is also stringent keeping in mind the need to gather good functional performances with the development of ecofriendly materials and processes. In this study, we propose a green fabrication method for the synthesis of silver nanoparticles supported on oxidized nanocellulose (ONCs), acting as both template and reducing agent. The complete structural and morphological characterization shows that well-dispersed and crystalline Ag nanoparticles of about 10–20 nm were obtained in the cellulose matrix. The antibacterial properties of Ag-nanocomposites (Ag–ONCs) were evaluated through specific Agar diffusion tests against E. coli bacteria, and the results clearly demonstrate that Ag–ONCs possess high long-lasting antibacterial behavior, retained up to 85% growth bacteria inhibition, even after 30 days of incubation. Finally, cell viability assays reveal that Ag-ONCs show a significant cytotoxicity in mouse embryonic fibroblasts.     

Effect of brain-derived neurotrophic factor on activity-regulated cytoskeleton-associated protein gene expression in primary frontal cortical neurons. Comparison with NMDA and AMPA

The effect of brain-derived neurotrophic factor (BDNF) on activity-regulated cytoskeleton-associated protein (Arc) mRNA levels in primary neuronal cultures of rat frontal cortex was characterized pharmacologically and compared to the effect on expression of c-fos, bdnf, neuritin, cox-2 as examples of other immediate early genes. BDNF induced a very strong increase (around 100 fold) in Arc mRNA and the maximal effect seen at 25 ng/ml. The effect was dose-dependent with EC50 around 1.6 ng/ml. The time profile revealed a significant effect after 25 min. BDNF also increased levels of c-Fos, neuritin and BDNF mRNA, but not COX-2 mRNA. The pharmacological profile of NMDA and AMPA-induced arc gene expression in frontal cortical neurons was compared to BDNF. NMDA and AMPA increased Arc mRNA but their maximal effect did not exceed 20-fold. The effect of AMPA was completely blocked by the NMDA receptor antagonist MK-801. Further, the relative amount of Arc mRNA compared to c-Fos mRNA was higher for BDNF, equal for NMDA and lower for AMPA. These results demonstrate BDNF to be a highly potent and efficient inducer of arc gene expression in vitro, emphasizing the role of this growth factor in synaptic plasticity in the frontal cortex.     

Paradoxical relationship between chromosomal instability and survival outcome in cancer

Chromosomal instability (CIN) is associated with poor prognosis in human cancer. However, in certain animal tumor models elevated CIN negatively impacts upon organism fitness, and is poorly tolerated by cancer cells. To better understand this seemingly contradictory relationship between CIN and cancer cell biological fitness and its relationship with clinical outcome, we applied the CIN70 expression signature, which correlates with DNA-based measures of structural chromosomal complexity and numerical CIN in vivo, to gene expression profiles of 2,125 breast tumors from 13 published cohorts. Tumors with extreme CIN, defined as the highest quartile CIN70 score, were predominantly of the estrogen receptor negative (ER(-)), basal-like phenotype and displayed the highest chromosomal structural complexity and chromosomal numerical instability. We found that the extreme CIN/ER(-) tumors were associated with improved prognosis relative to tumors with intermediate CIN70 scores in the third quartile. We also observed this paradoxical relationship between CIN and prognosis in ovarian, gastric, and non-small cell lung cancer, with poorest outcome in tumors with intermediate, rather than extreme, CIN70 scores. These results suggest a nonmonotonic relationship between gene signature expression and HR for survival outcome, which may explain the difficulties encountered in the identification of prognostic expression signatures in ER(-) breast cancer. Furthermore, the data are consistent with the intolerance of excessive CIN in carcinomas and provide a plausible strategy to define distinct prognostic patient cohorts with ER(-) breast cancer. Inclusion of a surrogate measurement of CIN may improve cancer risk stratification and future therapeutic approaches.     

Evidence summary: is smoking cessation an effective and cost-effective service to be introduced in NHS dentistry?

Since August 2009, members of the Primary Care Dentistry Research Forum (www.dentistryresearch.org) have taken part in an online vote to identify questions in day-to-day practice that they felt most needed to be answered with conclusive research. The question that receives the most votes each month forms the subject of a critical appraisal of the relevant literature. Each month a new round of voting takes place to decide which further questions will be reviewed. Dental practitioners and dental care professionals are encouraged to take part in the voting and submit their own questions to be included in the vote by joining the website. The paper below details a summary of the findings of the eighth critical appraisal. In order to address the question raised by the primary care dentistry research forum, first any international study was included that evaluated the effectiveness smoking cessation in dental practice. The aim was to understand whether smoking cessation in dental practice is an effective treatment strategy to increase tobacco cessation and abstinence. Moreover, this rapid assessment intended to identify whether there are certain types of smoking cessation intervention (or components of an intervention) in dental settings that are more effective than the others. In order to determine the applicability of the results to the NHS, we also looked for studies evaluating the cost-effectiveness of these interventions in NHS dentistry, studies reporting the current practice in NHS dentistry and finally qualitative and quantitative studies describing and evaluating the experience and views of dentists in the UK regarding implementing smoking cessation interventions in dental settings. The latter studies would help us to identify the possible barriers and facilitators in implementing these interventions in a dental setting. In conclusion, the critical appraisal of the international literature suggests that behavioural intervention for smoking cessation involving oral health professionals is an effective method of reducing tobacco use in smokers and users of smokeless tobacco and preventing uptake in non-smokers. There is not enough evidence available to assess whether these interventions are cost-effective and the effectiveness of one intervention (or component of the intervention) over another is not clear. The evaluation of the UK-related literature shows that private dental practices deliver more smoking cessation activities than their NHS counterparts. NHS practitioners report lack of reimbursement from the NHS, lack of time and training and fears over patient response as barriers to delivering smoking cessation interventions. We did not find studies evaluating the cost-effectiveness of the intervention in the UK.     

Evaluation of the antifibrotic effect of fenofibrate and rosiglitazone on bleomycin-induced pulmonary fibrosis in rats

Idiopathic pulmonary fibrosis is the most prevalent chronic fibrosing lung disease. Peroxisome proliferator-activated receptors-gamma agonists provide potential therapy for fibrotic diseases of the lung. Peroxisome proliferator-activated receptors-alpha agonists may be helpful in the treatment of lung inflammatory diseases, however their therapeutic potential on the "fibro-proliferative" process and extracellular matrix accumulation in idiopathic pulmonary fibrosis has been less well studied. So, the present study was conducted to evaluate the anti-fibrotic effects of fenofibrate (peroxisome proliferator-activated receptors-alpha agonist) alone and in combination with rosiglitazone (peroxisome proliferator-activated receptors-gamma agonist) on lung injury induced by bleomycin administration. Oral administration of either rosiglitazone (5 mg/kg/d) or fenofibrate (100 mg/kg/d) for 14 days, attenuated the severity of bleomycin-induced lung injury and fibrosis through decreasing lung water contents, lung fibrotic grading, lung hydroxyproline contents and lung transforming growth factor-beta1 levels; with no significant difference between them. Combined low doses of rosiglitazone (1 mg/kg/d) and fenofibrate (30 mg/kg/d) provided more benefits than full separate doses of each on the deleterious effects accompanied bleomycin administration. These findings suggested the potential use of peroxisome proliferator-activated receptors-alpha ligands as anti-fibrotic agents in lung fibrosis. Additionally, the concurrent administration of fenofibrate and rosiglitazone in low doses has synergistic effect and enhanced the beneficial effects afforded by either fenofibrate or rosiglitazone.     

The pharmacological profile of ELIC, a prokaryotic GABA-gated receptor

The Erwinia ligand-gated ion channel (ELIC) is a bacterial homologue of vertebrate Cys-loop ligand-gated ion channels. It is activated by GABA, and this property, combined with its structural similarity to GABA(A) and other Cys-loop receptors, makes it potentially an excellent model to probe their structure and function. Here we characterise the pharmacological profile of ELIC, examining the effects of compounds that could activate or inhibit the receptor. We confirm that a range of amino acids and classic GABA(A) receptor agonists do not elicit responses in ELIC, and we show the receptor can be at least partially activated by 5-aminovaleric acid and γ-hydroxybutyric acid, which are weak agonists. A range of GABA(A) receptor non-competitive antagonists inhibit GABA-elicited ELIC responses including α-endosulfan (IC(50) = 17 μM), dieldrin (IC(50) = 66 μM), and picrotoxinin (IC(50) = 96 μM) which were the most potent. Docking suggested possible interactions at the 2' and 6' pore-lining residues, and mutagenesis of these residues supports this hypothesis for α-endosulfan. A selection of compounds that act at Cys-loop and other receptors also showed some efficacy at blocking ELIC responses, but most were of low potency (IC(50) > 100 μM). Overall our data show that a number of compounds can inhibit ELIC, but it has limited pharmacological similarity to GLIC and to Cys-loop receptors.