Detection of erosions in the rheumatoid hand; a comparative study of multidetector computerized tomography versus magnetic resonance scanning

OBJECTIVE: To compare the detection and scoring of erosions in patients with rheumatoid arthritis (RA) using magnetic resonance (MR) and multidetector helical computerized tomographic (CT) scanning. METHODS: Comparative CT and MR scans of the dominant wrist were obtained from 9 patients with RA and clinical examination was performed to assess disease activity. MR and CT scans were scored for erosions and MR scans for bone edema by 2 radiologists using a validated system. Radiographs of the hands and feet were also scored for erosions using the modified Sharp score. RESULTS: In 117 of 135 (87%) sites there was concordance for erosions between MR and CT scans. At the remaining 18/135 sites (13%), erosions were identified by CT but not MR in 12/135 (9%) and by MR but not CT in 6/135 (4%). Partial volume artefacts on MR images and shifts in slice position were the most common reasons for erosion mismatch between MR and CT. The mean CT bone erosion score was significantly higher than the MR erosion score when individual bony sites were examined (p = 0.024), with the greatest difference being at the metacarpal bases. The total bone erosion score also tended to be higher on CT than MR [median scores of 20 (range 0-66) and 12 (0-51), respectively; p = 0.060]. MR and CT erosion scores correlated strongly with the total Sharp score (r = 0.93, p = 0.0002 and r = 0.94, p = 0.0002, respectively) and with the Disease Activity Score (MR: r = 0.77, p = 0.02; CT: r = 0.71, p = 0.03). CONCLUSION: Most erosions were detected using both modalities, but erosion scores were higher on CT than MR scans, especially at the metacarpal bases. It is possible that small erosions in some regions are more easily detected by CT because of its ability to clearly delineate cortical bony margins.     

Understanding Athletic Trainers' Beliefs Toward a Multifacted Sport-Related Concussion Approach: Application of the Theory of Planned Behavior

Context:

Practice guidelines recommend a multifaceted approach for managing concussions, but a relatively small percentage of athletic trainers (ATs) follow these recommendations. Understanding ATs'' beliefs toward the recommended concussion practice guidelines is the first step in identifying interventions that could increase compliance. The theory of planned behavior (TPB) allows us to measure ATs'' beliefs toward the recommended concussion practice guidelines.

Objective:

To examine the influence of ATs'' beliefs toward the current recommended concussion guidelines on concussion-management practice through an application of the TPB.

Design:

Cross-sectional study.

Setting:

A Web link with a survey was e-mailed to 1000 randomly selected members of the National Athletic Trainers'' Association (NATA).

Patients or Other Participants:

A total of 221 certified ATs working in secondary school/clinic, high school, and college/university settings.

Main Outcome Measure(s):

A 66-item survey reflecting the current recommended concussion guidelines of the NATA and International Conference on Concussion in Sport was created to measure beliefs using the TPB constructs attitude toward the behavior (BA), subjective norms (SN), perceived behavioral control (PBC), and behavioral intention (BI) of ATs. We used a linear multiple regression to determine if the TPB constructs BA, SN, and PBC predicted BI and if PBC and BI predicted behavior according to the TPB model.

Results:

We found that BA, SN, and PBC predicted BI (R = 0.683, R² = 0.466, F_3,202 = 58.78, P < .001). The BA (t₂₀₂ = 5.53, P < .001) and PBC (t₂₀₂ = 9.64, P < .001) contributed to the model, whereas SN (t₂₀₂ = −0.84, P = .402) did not. The PBC and BI predicted behavior (R = 0.661, R² = 0.437, F_2,203 = 78.902, P < .001).

Conclusions:

In this sample, the TPB constructs predicted BI and behavior of ATs'' compliance with recommended concussion-management guidelines. The BA and PBC were the most influential constructs, indicating that those with positive attitudes toward concussion-management recommendations are more likely to implement them, and ATs are less likely to implement them when they do not believe they have the power to do so. We theorize that interventions targeting ATs'' attitudes and control perceptions will lead to improved compliance.Key Words: concussion management, traumatic brain injuries, practice guidelines

Key Points

• Using the theory of planned behavior constructs to investigate the application of recommended concussion-management guidelines by athletic trainers, we found that attitudes toward the behavior and perceived behavioral control were most influential.
• Interventions that take into account athletic trainers'' attitudes and perceived control may help to increase compliance with concussion-management guidelines.

Given estimates of 1.6 to 3.8 million sport-related concussions occurring in the United States each year,¹ sports medicine professionals must be able to evaluate and manage concussions properly. With most athletic injuries, the sports medicine team can clearly define the presence and severity of an injury; however, factors such as an athlete''s age² and sex³ and the location and magnitude of an impact⁴ can make it difficult to clearly define the severity of a concussion.To help sports medicine professionals who care for concussed athletes, a number of organizations^5–8 have proposed the use of a multifaceted approach to evaluate and manage sport-related concussions. The guidelines established by these organizations for the evaluation and management of sport-related concussions endorse the use of (1) a clinical examination,^5,7,8 (2) a symptom checklist,⁶ (3) postural-control assessment,^6–8 (4) neuropsychological testing,^5–8 (5) baseline testing when available for high–concussion-risk athletes,^6,7 and (6) a return-to-play protocol with a daily increase in activity once an athlete has been deemed symptom free.^5–8 Also, the recommendations emphasize that it is imperative to focus on the athlete''s data gathered from the evaluation when making a return-to-play (RTP) decision throughout the concussion-management process rather than relying on a predetermined timeline.^6–8The multifaceted approach to evaluating and managing concussions has been recommended since 2002.⁵ Sports medicine professionals have shown a steady but slow increase in compliance with the recommendations over the past decade, yet barriers to incorporation of these standards remain.^9–11 To improve compliance, it is important to understand sports medicine professionals'' beliefs about the multifaceted approach to concussion management.¹² If we can understand why a minority of sports medicine professionals use recommended concussion-management guidelines, we can identify strategies to change common practices. The theory of planned behavior (TPB) offers an avenue to investigate these beliefs.The TPB focuses on theoretical constructs that are concerned with individual motivational factors (behavioral intention [BI]) as determinants of the likelihood of performing a specific behavior.^13–15 The TPB includes measures of attitude, subjective normative perceptions, and perceived behavioral control (PBC) that determine BI, with BI leading to a behavior. The TPB assumes that all other factors, including demographics and the environment, operate through the model constructs and do not independently contribute to explaining the likelihood of performing a behavior.The TPB has 4 guiding constructs: (1) attitude toward the behavior (BA), or an individual''s positive or negative evaluation of self-performance of a behavior and an individual''s belief about the consequences of that behavior; (2) subjective norms (SN), or an individual''s perception of what other persons think about the individual performing the behavior and the individual''s motivation to comply; (3) PBC, or a perception that the individual has control over performing a behavior; and (4) BI, or the individual''s intent to perform or not perform the behavior based on the weight of the first 3 constructs (Figure 1). The TPB depicts behavior (B) as a linear regression function: B = w₁BI + w₂PBC, where w₁ and w₂ are empirically determined weights.Open in a separate windowFigure 1. Theory of planned behavior results with Pearson r (beta weight) for each construct. ^a Significant at P < .001.The following is an example of how the TPB can help us understand the decision-making process of a sports medicine professional in determining whether to use a concussion-management technique. An athletic trainer (AT) believes it is important to implement neuropsychological testing after every concussion (BA). The AT may or may not be influenced by his or her perceptions about how the head coach feels regarding this concussion-management tool (SN). Finally, the AT must decide if he or she has enough authority in the athletic department to acquire the funds to purchase the neuropsychological tests (PBC). According to the TPB, the summation of these 3 constructs results in the AT''s intention to perform neuropsychological tests. An AT who intends to perform neuropsychological tests is more likely to do so. However, if the AT feels that he or she lacks full volitional control over the behavior (PBC), the BI may have less influence on behavior.To understand why a minority of sports medicine professionals are currently applying the concussion-management guidelines, we would like to understand their beliefs and perceptions regarding the guidelines. Therefore, the purpose of our study was to examine the influence of ATs'' attitudes and beliefs toward the current recommended concussion-management guidelines through an application of the TPB.     

Knee extensor strength differences in obese and healthy-weight 10-to 13-year-olds

The purpose of this study was to investigate if obese children have reduced knee extensor (KE) strength and to explore the relationship between adiposity and KE strength. An observational case–control study was conducted in three Australian states, recruiting obese [N = 107 (51 female, 56 male)] and healthy-weight [N = 132 (56 female, 76 male)] 10- to 13-year-old children. Body mass index, body composition (dual energy X-ray absorptiometry), isokinetic/isometric peak KE torques (dynamometry) and physical activity (accelerometry) were assessed. Results revealed that compared with their healthy-weight peers, obese children had higher absolute KE torques (P ≤ 0.005), equivocal KE torques when allometrically normalized for fat-free mass (FFM) (P ≥ 0.448) but lower relative KE torques when allometrically normalized for body mass (P ≤ 0.008). Adjustments for maternal education, income and accelerometry had little impact on group differences, except for isometric KE torques relative to body mass which were no longer significantly lower in obese children (P ≥ 0.013, not significant after controlling for multiple comparisons). Percent body fat was inversely related to KE torques relative to body mass (r = ?0.22 to ?0.35, P ≤ 0.002), irrespective of maternal education, income or accelerometry. In conclusion, while obese children have higher absolute KE strength and FFM, they have less functional KE strength (relative to mass) available for weight-bearing activities than healthy-weight children. The finding that FFM-normalized KE torques did not differ suggests that the intrinsic contractile properties of the KE muscles are unaffected by obesity. Future research is needed to see if deficits in KE strength relative to mass translate into functional limitations in weight-bearing activities.     

High intake of cholesterol results in less atherogenic low-density lipoprotein particles in men and women independent of response classification

The influence of a high-cholesterol diet on the atherogenicity of the low-density lipoprotein (LDL) particle was examined by measuring LDL peak diameter and composition, LDL susceptibility to oxidation, and the distribution of cholesterol between LDL subclasses. The crossover intervention randomly assigned 27 premenopausal women and 25 men (18 to 50 years) to an egg (640 mg/d additional dietary cholesterol) or placebo (0 mg/d additional dietary cholesterol) diet for 30 days, followed by a 3-week washout period. Subjects were classified as either hyperresponders (>2.5 mg/dL increase in plasma cholesterol for each 100 mg additional dietary cholesterol consumed) or hyporesponders to dietary cholesterol. Sex was found to have a significant effect on 3 of the parameters examined. LDL peak diameter was significantly larger (P <.005) in females (26.78 +/- 0.59 nm, n = 27) as compared with males (26.52 +/- 0.49 nm, n = 25), regardless of response to dietary cholesterol. The LDL particles of the male participants also had a higher number of triglyceride (TG) and cholesteryl ester (CE) molecules (P <.01); however, cholesterol ester transfer protein (CETP) activity was higher in females (P <.05). Response classification also revealed significant differences in the determination of LDL subclasses. Independent of sex, the LDL-1 particle (P <.05), which is considered to be less atherogenic, was predominant in hyperresponders and this finding was associated with increased cholesterol intake (interactive effect, P <.001). In addition, CETP and lecithin: cholesterol acyltransferase (LCAT) activities were higher in hyperresponders during the egg period (interactive effect, P <.05). Sex, response to cholesterol intake, and diet were not found to affect the susceptibility of LDL to oxidation (P > 0.5). Because LDL peak diameter was not decreased and the larger LDL-1 subclass was greater in hyperresponders following egg intake, these data indicate that the consumption of a high-cholesterol diet does not negatively influence the atherogenicity of the LDL particle.     

ZnO Nanoparticles Impose a Panmetabolic Toxic Effect Along with Strong Necrosis,Inducing Activation of the Envelope Stress Response in Salmonella enterica Serovar Enteritidis

In this study, we tested the antimicrobial activity of three metal nanoparticles (NPs), ZnO, MgO, and CaO NPs, against Salmonella enterica serovar Enteritidis in liquid medium and on solid surfaces. Out of the three tested metal NPs, ZnO NPs exhibited the most significant antimicrobial effect both in liquid medium and when embedded on solid surfaces. Therefore, we focused on revealing the mechanisms of surface-associated ZnO biocidal activity. Using the global proteome approach, we report that a great majority (79%) of the altered proteins in biofilms formed by Salmonella enterica serovar Enteritidis were downregulated, whereas a much smaller fraction (21%) of proteins were upregulated. Intriguingly, all downregulated proteins were enzymes involved in a wide range of the central metabolic pathways, including translation; amino acid biosynthetic pathways; nucleobase, nucleoside, and nucleotide biosynthetic processes; ATP synthesis-coupled proton transport; the pentose phosphate shunt; and carboxylic acid metabolic processes, indicating that ZnO NPs exert a panmetabolic toxic effect on this prokaryotic organism. In addition to their panmetabolic toxicity, ZnO NPs induced profound changes in cell envelope morphology, imposing additional necrotic effects and triggering the envelope stress response of Salmonella serovar Enteritidis. The envelope stress response effect activated periplasmic chaperones and proteases, transenvelope complexes, and regulators, thereby facilitating protection of this prokaryotic organism against ZnO NPs.