Influence of third-body particles originating from bone void fillers on the wear of ultra-high-molecular-weight polyethylene

Calcium sulfate bone void fillers are increasingly being used for dead space management in infected arthroplasty revision surgery. The presence of these materials as loose beads close to the bearing surfaces of joint replacements gives the potential for them to enter the joint becoming trapped between the articulating surfaces; the resulting damage to cobalt chrome counterfaces and the subsequent wear of ultra-high-molecular-weight polyethylene is unknown. In this study, third-body damage to cobalt chrome counterfaces was simulated using particles of the calcium sulfate bone void fillers Stimulan® (Biocomposites Ltd., Keele, UK) and Osteoset® (Wright Medical Technology, TN, USA) using a bespoke rig. Scratches on the cobalt chrome plates were quantified in terms of their density and mean lip height, and the damage caused by the bone void fillers was compared to that caused by particles of SmartSet GMV PMMA bone cement (DePuy Synthes, IN, USA). The surface damage from Stimulan® was below the resolution of the analysis technique used; SmartSet GMV caused 0.19 scratches/mm with a mean lip height of 0.03 µm; Osteoset® led to a significantly higher number (1.62 scratches/mm) of scratches with a higher mean lip height (0.04 µm). Wear tests of ultra-high-molecular-weight polyethylene were carried out in a six-station multi-axial pin on plate reciprocating rig against the damaged plates and compared to negative (highly polished) and positive control plates damaged with a diamond stylus (2 µm lip height). The wear of ultra-high-molecular-weight polyethylene was shown to be similar against the negative control plates and those damaged with third-body particles; there was a significantly higher (p < 0.001) rate of ultra-high-molecular-weight polyethylene wear against the positive control plates. This study showed that bone void fillers of similar composition can cause varying damage to cobalt chrome counterfaces. However, the lip heights of the scratches were not of sufficient magnitude to increase the wear of ultra-high-molecular-weight polyethylene above that of the negative controls

The influence of a calcium sulphate bone void filler on the third-body damage and polyethylene wear of total knee arthroplasty

Objectives: Bone void fillers are increasingly being used for dead space management in arthroplasty revision surgery. The aim of this study was to investigate the influence of calcium sulphate bone void filler (CS-BVF) on the damage and wear of total knee arthroplasty using experimental wear simulation. Methods: A total of 18 fixed-bearing U2 total knee arthroplasty system implants (United Orthopedic Corp., Hsinchu, Taiwan) were used. Implants challenged with CS-BVF were compared with new implants (negative controls) and those intentionally scratched with a diamond stylus (positive controls) representative of severe surface damage (n = 6 for each experimental group). Three million cycles (MC) of experimental simulation were carried out to simulate a walking gait cycle. Wear of the ultra-high-molecular-weight polyethylene (UHMWPE) tibial inserts was measured gravimetrically, and damage to articulating surfaces was assessed using profilometry. Results: There was no significant difference (p  >  0.05) between the wear rate of implants challenged with CS-BVF (3.3 mm3/MC (95% confidence interval (CI) 1.8 to 4.8)) and the wear rate of those not challenged (2.8 mm3/MC (95% CI 1.3 to 4.3)). However, scratching the cobalt-chrome (CoCr) significantly (p < 0.001) increased the wear rate (20.6 mm3/MC (95% CI 15.5 to 25.7)). The mean surface roughness of implants challenged with CS-BVF was equivalent to negative controls both after damage simulation (p = 0.98) and at the conclusion of the study (p = 0.28). Conclusion: When used close to articulating surfaces, a low-hardness, high-purity CS-BVF had no influence on wear. When trapped between the articulating surfaces of a total knee arthroplasty, CS-BVF did not scratch the surface of CoCr femoral components, nor did it increase the wear of UHMWPE tibial inserts compared with undamaged negative controls

Consumers’ perceived corporate social responsibility evaluation and support: the moderating role of consumer information

This study analyzes how consumers’ evaluations of various dimensions of corporate social responsibility (CSR) affect their support of it and how consumers’ searches for CSR information influence such evaluations. The empirical analysis relies on data on CSR from a wide representative sample of 3543 Spanish hotel consumers. We use hierarchical multiple regressions to test the relationships and use factorial analysis to test the validity of the different CSR dimensions. The proposed positive effects of legal, ethical, economic, philanthropic and environmental dimensions of CSR on consumers’ support for corporate reputation, the selection of an establishment, and future purchase intention are corroborated, although they are only partially corroborated in the case of the economic dimension. These relationships are moderated in some cases by consumers’ search for information about hotels’ CSR practices. Managerial and economic implications are derived from the results

Pre-Stressor Interference Control and Intrusive Memories

Although intrusive imagery is a common response in the aftermath of a stressful or traumatic event, only a minority of trauma victims show persistent re-experiencing and related psychopathology. Individual differences in pre-trauma executive control possibly play a critical role. Therefore, this study investigated whether a relatively poor pre-stressor ability to resist proactive interference in working memory might increase risk for experiencing undesirable intrusive memories after being exposed to a stressful event. Non-clinical participants (N = 85) completed a modified version of a widely used test of interference control in working memory (CVLT; Kramer and Delis 1991) and subsequently watched an emotional film fragment. Following presentation of the fragment, intrusive memories were recorded in a 1-week diary and at a follow up session 7 days later. A relatively poor ability to resist proactive interference was related to a relatively high frequency of film-related intrusive memories. This relationship was independent of neuroticism and gender. These findings are consistent with the idea that a pre-morbid deficit in the ability to resist proactive interference reflects a vulnerability factor for experiencing intrusive memories after trauma exposure

Human resources for health planning and management in the Eastern Mediterranean region: facts, gaps and forward thinking for research and policy

BACKGROUND: The early decades of the 21(st )century are considered to be the era of human resources for health (HRH). The World Health Report (WHR) 2006 launched the Health Workforce Decade (2006–2015), with high priority given for countries to develop effective workforce policies and strategies. In many countries in the Eastern Mediterranean Region (EMR), particularly those classified as Low and Low-Middle Income Countries (LMICs), the limited knowledge about the nature, scope, composition and needs of HRH is hindering health sector reform. This highlights an urgent need to understand the current reality of HRH in several EMR countries. The objectives of this paper are to: (1) lay out the facts on what we know about the HRH for EMR countries; (2) generate and interpret evidence on the relationship between HRH and health status indicators for LMICs and middle and high income countries (MHICs) in the context of EMR; (3) identify and analyze the information gaps (i.e. what we do not know) and (4) provide forward thinking by identifying priorities for research and policy. METHODS: The variables used in the analysis were: nurse and physician density, gross national income, poverty, female literacy, health expenditure, Infant Mortality Rate (IMR), Under 5 Mortality Rate (U5MR), Maternal Mortality Rate (MMR) and Life Expectancy (LE). Univariate (charts), bivariate (Pearson correlation) and multivariate analysis (linear regression) was conducted using SPSS 14.0, besides a synthesis of HRH literature. RESULTS: Results demonstrate the significant disparities in physician and nurse densities within the EMR, particularly between LMICs and MHICs. Besides this, significant differences exist in health status indicators within the EMR. Results of the Pearson correlation revealed that physician and nurse density, as well as female literacy in EMR countries were significantly correlated with lower mortality rates and higher life expectancy. Results of the regression analysis for both LMICs and MHICs reveal that physician density is significantly associated with all health indicators for both income groups. Nurse density was found to be significantly associated with lower MMR for the two income groups. Female literacy is notably related to lower IMR and U5MR for both income groups; and only with MMR and LE in LMICs. Health expenditure is significantly associated with lower IMR and U5MR only for LMICs. Based on results, gap analysis and the literature synthesis, information gaps and priorities were identified. CONCLUSION: The implication of the results discussed in this paper will help EMR countries, particularly LMICs, determine priorities to improve health outcomes and achieve health-related Millenium Development Goals

Salmonella enterica ssp. arizonae infection in a 43-year-old Italian man with hypoglobulinemia: a case report and review of the literature

<p>Abstract</p> <p>Introduction</p> <p><it>Salmonella enterica </it>ssp. <it>arizonae </it>is an uncommon human pathogen with serious infections reported in immunocompromised hosts. In Europe, only a few cases have been described. Patients with this infection usually have a history of contact with reptiles or travel abroad. We present a case report of infection in a patient with hypoglobulinemia and a literature review.</p> <p>Case presentation</p> <p>We describe the case of a 43-year-old Caucasian Italian man with hypoglobulinemia who presented to our hospital with sepsis and diarrhea. A stool culture yielded <it>S. enterica </it>ssp. <it>arizonae</it>. Our patient was treated with oral ciprofloxacin and made a full recovery. We also present a review of the cases of <it>S. enterica </it>ssp. <it>arizonae </it>infections previously reported in Europe.</p> <p>Conclusions</p> <p>The majority of infections from <it>S. enterica </it>ssp. <it>arizonae </it>occur in patients who are immunocompromised. Data from the literature suggests that it may be difficult to eradicate the bacteria and thus, prolonged antibiotic courses are often used. It would be advisable for clinicians to investigate for pre-existing immune dysfunction if <it>S. enterica </it>ssp. <it>arizonae </it>is isolated. In Italy, although there have only been a few cases, the likely route of transmission remains unclear and requires further surveillance.</p

Correlates of sunscreen use among high school students: a cross-sectional survey

Abstract Background Adolescents put themselves at risk of later skin cancer development and accelerated photo-aging due to their high rates of ultraviolet radiation exposure and low rates of skin protection. The purpose of the current study was to determine which of the Integrative Model constructs are most closely associated with sunscreen use among high school students. Methods The current study of 242 high school students involved a survey based on the Integrative Model including demographic and individual difference factors, skin protection-related beliefs and outcome evaluations, normative beliefs, self-efficacy, sunscreen cues and availability, intentions, and sunscreen use. Our analyses included multiple linear regressions and bootstrapping to test for mediation effects. Results Sunscreen use was significantly associated with female gender, greater skin sensitivity, higher perceived sunscreen benefits, higher skin protection importance, more favorable sunscreen user prototype, stronger skin protection norms, greater perceived skin protection behavioral control, and higher sunscreen self-efficacy. Intentions to use sunscreen mediated the relationships between most skin protection-related beliefs and sunscreen use. Conclusions The current study identified specific variables that can be targeted in interventions designed to increase sunscreen use among adolescents.</p

Sun protection and sunbathing practices among at-risk family members of patients with melanoma

<p>Abstract</p> <p>Background</p> <p>Despite the increased level of familial risk, research indicates that family members of patients with melanoma engage in relatively low levels of sun protection and high levels of sun exposure. The goal of this study was to evaluate a broad range of demographic, medical, psychological, knowledge, and social influence correlates of sun protection and sunbathing practices among first-degree relatives (FDRs) of melanoma patients and to determine if correlates of sun protection and sunbathing were unique.</p> <p>Methods</p> <p>We evaluated correlates of sun protection and sunbathing among FDRs of melanoma patients who were at increased disease risk due to low compliance with sun protection and skin surveillance behaviors. Participants (<it>N </it>= 545) completed a phone survey.</p> <p>Results</p> <p>FDRs who reported higher sun protection had a higher education level, lower benefits of sunbathing, greater sunscreen self-efficacy, greater concerns about photo-aging and greater sun protection norms. FDRs who reported higher sunbathing were younger, more likely to be female, endorsed fewer sunscreen barriers, perceived more benefits of sunbathing, had lower image norms for tanness, and endorsed higher sunbathing norms.</p> <p>Conclusion</p> <p>Interventions for family members at risk for melanoma might benefit from improving sun protection self-efficacy, reducing perceived sunbathing benefits, and targeting normative influences to sunbathe.</p

Peer-Victimization and Mental Health Problems in Adolescents: Are Parental and School Support Protective?

The aim of this study was to investigate the frequency and effects of peer-victimization on mental health problems among adolescents. Parental and school support were assumed as protective factors that might interact with one another in acting as buffers for adolescents against the risk of peer-victimization. Besides these protective factors, age and gender were additionally considered as moderating factors. The Social and Health Assessment survey was conducted among 986 students aged 11–18 years in order to assess peer-victimization, risk and protective factors and mental health problems. For mental health problems, the Strengths and Difficulties Questionnaire (SDQ) was used. Effects of peer-victimization on mental health problems were additionally compared with normative SDQ data in order to obtain information about clinically relevant psychopathology in our study sample. Results of this study show that peer-victimization carries a serious risk for mental health problems in adolescents. School support is effective in both male and female adolescents by acting as a buffer against the effect of victimization, and school support gains increasing importance in more senior students. Parental support seems to be protective against maladjustment, especially in peer-victimized girls entering secondary school. Since the effect of peer-victimization can be reduced by parental and school support, educational interventions are of great importance in cases of peer-victimization