Damages of the tibial post in constrained total knee prostheses in the early postoperative course – a scanning electron microscopic study of polyethylene inlays

<p>Abstract</p> <p>Background</p> <p>Investigation of the risk of fracture of the polyethylene (PE) inlay in constrained total knee prostheses.</p> <p>Methods</p> <p>Three unused and seven polyethylene inlays that had been implanted in a patient's knee for an average of 25.4 months (min 1.1 months, max 50.2 months) were investigated using scanning electron microscopy (SEM). All inlays were of the same type and size (Genesis II constrained, Smith & Nephew). The PE surface at the transition from the plateau to the post was analyzed.</p> <p>Results</p> <p>The unused inlays had fissure-free surfaces. All inlays that had been implanted in a patient's knee already had distinct fissures at the front and backside of the post.</p> <p>Conclusion</p> <p>The fissures of the transition from the plateau to the post indicated a loading-induced irreversible mechanical deformation and possibly cause the fracture of the inlay.</p

Does replacement of missing dental units with resin-retained bridges improve oral health-related quality of life?: A systematic review

Objectives To assess the current literature in regard to two research questions: • Does placement of a 2-unit cantilever RRB to replace a missing dental unit improve oral health-related quality of life (OHRQoL) in patients over 18 years old? • Are there any differences in OHRQoL between different methods of replacing missing teeth? Methods Systematic review following the Preferred Reporting Items for Systemic Reviews and Meta-Analysis statement (PRISMA) statement. Data/sources MEDLINE via Ovid, Scopus, PsycINFO via Ovid, Cochrane Library, Web of Science and clinicaltrials.gov were searched (Jan 1980 to Nov 2018) using high-level MeSH terms for studies published in English, investigating OHRQoL, using valid indices. Risk of bias (RoB) Determined using Cochrane RoB tool and ROBINS-I. Evidence certainty Grading of Recommendations, Assessment, Development and Evaluation (GRADE) Working Group tool. Results Study Selection: 280 articles were identified; 270 were excluded after abstract review, 7 after examining full text, leaving 3 articles (3 studies, 188 participants, 172 analysed) included in this review; one RCT and two observational studies. Synthesis of results: There was significant heterogeneity and no meta-analysis was possible. Description of effect: One pre-post study design found provision of 2-unit RRBs significantly reduced the total OHIP-49 score (effect size 0.67), compared with an untreated control. One case-control study found no differences in total OHIP-49 between individuals treated with RRB or implant-supported crown. Major complications related to a worse OHRQoL. Discussion Quality of evidence: The overall RoB assessments were one study “some concerns” and two studies “serious”. The GRADE assessment was “moderate” for one comparison and “low” for two comparisons. Clinical significance: A 2-unit cantilever RRB to replace one missing tooth probably results in a large improvement in oral health-related quality of life. Clinicians should ensure that the correct investigations and design of prosthesis are prescribed to help reduce any failures that may impact on OHRQoL

The role of the dentate gyrus and adult neurogenesis in hippocampal-basal ganglia associated behaviour

The ability of the brain to continually generate new neurons throughout life is one of the most intensely researched areas of modern neuroscience. While great advancements in understanding the biochemical mechanisms of adult neurogenesis have been made, there remain significant obstacles and gaps in connecting neurogenesis with behavioural and cognitive processes such as learning and memory. The purpose of the thesis was to examine by review and laboratory experimentation the role of the dentate gyrus and of adult neurogenesis within the hippocampus in the performance of cognitive tasks dependent on the hippocampal formation and hippocampal-basal ganglia interactions. Advancement in understanding the role of neurogenesis in these processes may assist in improving treatments for common brain injury and cognitive diseases that affect this region of the brain. Mild chronic stress reduced the acquisition rate of a stimulus-response task (p=0.043), but facilitated the acquisition of a discrimination between a small and a large reward (p=0.027). In locomotor activity assays, chronic stress did not shift the dose-response to methamphetamine. Analysis of 2,5-bromodeoxyuridine incorporation showed that, overall, chronic mild stress did not effect survival of neuronal progenitors . However, learning of the tasks had a positive influence on cell survival in stressed animals (p=0.038). Microinjections of colchicine produced significant lesions of the dentate gyrus and surrounding CA1-CA3 and neocortex. Damage to these regions impaired hippocampal-dependent reference memory (p=0.054) while preserving hippocampal independent simple discrimination learning. In a delay discounting procedure, the lesions did not induce impulsive-like behaviour when delay associated with a large reward was introduced. The experiments uphold a current theory that learning acts as a buffer to mitigate the negative effects of stress on neurogenesis

Interventions for dry mouth and hyposalivation in Sjögren’s syndrome: A systematic review and meta‐analysis

OBJECTIVES: Systematic review with meta-analysis of interventions for dry mouth symptoms and hyposalivation of Sjögren's syndrome (SS). MATERIALS AND METHODS: We searched MEDLINE, Cochrane Central and EMBASE up to February 2018 for randomized trials of interventions for dry mouth and hyposalivation of SS. The primary outcome was the mean change in xerostomia symptoms. The secondary outcomes included changes in salivary flow and quality of life. We used the Cochrane risk of bias tool for individual studies and the GRADE method to summarize the quality of evidence across studies for the included outcomes. RESULTS: Thirty-six studies (3,274 patients) were included in the systematic review. Results from the meta-analyses showed high-quality evidence that pilocarpine was superior to placebo in reducing dry mouth symptoms. We found moderate quality of evidence that pilocarpine, rituximab, and interferon-alpha were more effective than placebo in increasing salivary flow, with the relevant effect size being large for pilocarpine, and notably smaller for rituximab and interferon-alpha. CONCLUSION: Clinicians should be very confident in the beneficial effects of pilocarpine upon dry mouth symptoms of SS, and moderately confident that pilocarpine, rituximab and interferon-alpha can have beneficial effects upon salivary flow. Adverse events are common. The use of other treatment modalities cannot be supported on the basis of current evidence

A multidimensional analysis of the effect of occupational exposure to organic solvents on lung cancer risk: The ICARE study

Copyright Article author (or their employer) 2016. Background The association between lung cancer and occupational exposure to organic solvents is discussed. Since different solvents are often used simultaneously, it is difficult to assess the role of individual substances. Objectives The present study is focused on an in depth investigation of the potential association between lung cancer risk and occupational exposure to a large group of organic solvents, taking into account the well known risk factors for lung cancer, tobacco smoking and occupational exposure to asbestos. Methods We analysed data from the Investigation of occupational and environmental causes of respiratory cancers (ICARE) study, a large French population-based case–control study, set up between 2001 and 2007. A total of 2276 male cases and 2780 male controls were interviewed, and long-life occupational history was collected. In order to overcome the analytical difficulties created by multiple correlated exposures, we carried out a novel type of analysis based on Bayesian profile regression. Results After analysis with conventional logistic regression methods, none of the 11 solvents examined were associated with lung cancer risk. Through a profile regression approach, we did not observe any significant association between solvent exposure and lung cancer. However, we identified clusters at high risk that are related to occupations known to be at risk of developing lung cancer, such as painters. Conclusions Organic solvents do not appear to be substantial contributors to the occupational risk of lung cancer for the occupations known to be at risk.Ms Joëlle Fevotte for designing occupational questionnaires; all members of the MatGéné working group from the Institut de Veille Sanitaire and, Ms Brigitte Dananché and Mr Gwenaël GR Leday for his support in performing statistical analyse