Surface modification of Polyether-ether-ketone for enhanced cell response: a chemical etching approach

Polyether-ether-ketone (PEEK) is increasingly becoming popular in medicine because of its excellent mechanical strength, dimensional stability, and chemical resistance properties. However, PEEK being bioinert, has weak bone osseointegration properties, limiting its clinical applications. In this study, a porous PEEK structure was developed using a chemical etching method with 98 wt% sulfuric acids and three post-treatments were performed to improve bone cell adhesion and proliferation. Four groups of PEEK samples were prepared for the study: Control (untreated; Group 1); Etched with sulfuric acid and washed with distilled water (Group 2); Etched with sulfuric acid and washed with acetone and distilled water (Group 3); and Etched with sulfuric acid and washed with 4 wt% sodium hydroxide and distilled water (Group 4). Surface characterization of the different groups was evaluated for surface topology, porosity, roughness, and wettability using various techniques, including scanning electron microscopy, profilometer, and goniometer. Further chemical characterization was done using Energy-dispersive X-ray spectroscopy to analyze the elements on the surface of each group. Bone cell studies were conducted using cell toxicity and alkaline phosphatase activity (ALP) assays. The SEM analysis of the different groups revealed porous structures in the treatment groups, while the control group showed a flat topology. There was no statistically significant difference between the pore size within the treated groups. This was further confirmed by the roughness values measured with the profilometer. We found a statistically significant increase in the roughness from 7.22 × 10-3 μm for the control group to the roughness range of 0.1 µm for the treated groups (Groups 2-4). EDX analysis revealed the presence of a 0.1% weight concentration of sodium on the surface of Group 4, while sulfur weight percentage concentration was 1.1%, 0.1%, and 1.4% in groups 2, 3, and 4, respectively, indicating different surface chemistry on the surface due to different post-treatments. Cell toxicity decreased, and ALP activity increased in groups 3 and 4 over 7 days compared with the control group. It is demonstrated that the surface modification of PEEK using a chemical etching method with post-processing with either acetone or sodium hydroxide provides a nano-porous structure with improved properties, leading to enhanced osteoblastic cell differentiation and osteogenic potential.

A Case of Thrombotic Microangiopathy and Acute Sarcoidosis

Although sarcoidosis is an established cause of multiorgan dysfunction, acute presentation with thrombotic microangiopathy resulting in severe renal and hematological sequelae has not been reported. We describe the case of a patient presenting with hypercalcemia, pancreatitis, and acute renal failure, followed by microangiopathic hemolytic anemia. Although there were no significant respiratory symptoms, thoracic radiology and mediastinal lymph node biopsy results were in keeping with sarcoidosis as the underlying cause of this multisystem presentation. Corticosteroids were commenced with clinical and biochemical improvement. This novel case highlights the need to consider sarcoidosis as part of the differential diagnosis for unusual multiorgan presentations and for early multidisciplinary involvement in such cases to permit optimal treatment.

Abstract 5139: F. nucleatum induces invasive phenotypes in oral cancer cells in vitro

Oral cancer is one of the most common cancers that affect public health with 500,000 new cases diagnosed yearly worldwide. The behavior of oral cancer might be affected by bacterial pathogens present in the oral cavity. The association between periodontitis, a chronic infection that affect the periodontium, and oral cancer have been reported in many studies. However, the effect of interaction between periodontal bacteria and oral cancer cells on cancer progression and aggressiveness is not well studied. Therefore, we aim to investigate the effect of four major periodontal bacteria on cancer cell pathology and treatment response. Three oral cancer cell lines OQ01, BHY and HN were used. Periodontal infection was represented by four periodontal bacteria Porphyromonas gingivalis, Treponema denticola, Tannerella forsythia, and Fusobacterium nucleatum. These bacteria were used to infect the oral cancer cells as polybacterial infection. Further analysis was done on OQ01 with monobacterial infection. The level of different cytokines (IL8 and TGF-β) were quantified in the culture supernatants after 6 and 24 h using ELISA. After RNA isolation from cell lysate, the relative changes in expression of six different oncogenes (MMP1, MMP9, MYC, JAk1, ZEB1, and STAT3) were measured using RT-PCR. To further investigate the role of F. nucleatum in inducing autophagy, three strains of F. nucleatum (Vincinti, Polymorphum and Periodontium) were used and the levels of autophagy markers (ATG7, ATG12 and ULK1) were measured after 6 and 24 hours. The effect of F. nucleatum on cancer cell invasion was was done starting from 4 h after infection. Statistical analysis was done using two-tailed Student's t-test OQ01 alone showed significantly enhance IL-8 secretion after polyinfection (P= 0.0003); however, enhanced TFG-β secretion was detected in all cell lines tested (P= 0.004). Polybacterial infection of oral cancer cell lines also upregulated MMP1 and MMP9 (P= 0.002) (known to enhance cancer cell invasiveness), ZEB1 (known to induce epithelial mesenchymal transition in cancer cells), and MYC, JAK1 and STAT3 (oncogenes involved in cell survival). Further analysis using OQ01 cells in monobacterial infection showed that F. nucleatum alone had the same or greater effect as polybacterial infection (P= 0.001). These results showed that F. nucleatum was the main periodontal bacteria responsible for inducing invasive phenotype in these oral cancer cells. In addition, F. nucleatum was able to enhance cancer cell invasion in vitro. Furthermore, F. nucleatum appear to upregulate autophagy markers in vitro which can lead to enhanced cancer cell survival and chemoresistance. This study demonstrated that the interaction between oral cancer cells and periodontal bacteria might be both cancer cell- and bacteria-specific. Our study can be highly useful in examining how modulating oral cancer environment can improve treatment outcome.

Citation Format: Amani Harrandah, Sasanka S. Chukkapalli, Ann Progulske-Fox, William Dunn, Kesavalu Lakshmyya, Edward K. Chan. F. nucleatum induces invasive phenotypes in oral cancer cells in vitro [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5139.

Identification of the functional pathways altered by placental cell exposure to high glucose: lessons from the transcript and metabolite interactome

The specific consequences of hyperglycaemia on placental metabolism and function are incompletely understood but likely contribute to poor pregnancy outcomes associated with diabetes mellitus (DM). This study aimed to identify the functional biochemical pathways perturbed by placental exposure to high glucose levels through integrative analysis of the trophoblast transcriptome and metabolome. The human trophoblast cell line, BeWo, was cultured in 5 or 25 mM glucose, as a model of the placenta in DM. Transcriptomic analysis using microarrays, demonstrated 5632 differentially expressed gene transcripts (≥± 1.3 fold change (FC)) following exposure to high glucose. These genes were used to generate interactome models of transcript response using BioGRID (non-inferred network: 2500 nodes (genes) and 10541 protein-protein interactions). Ultra performance-liquid chromatography-mass spectrometry (MS) and gas chromatography-MS analysis of intracellular extracts and culture medium were used to assess the response of metabolite profiles to high glucose concentration. The interactions of altered genes and metabolites were assessed using the MetScape interactome database, resulting in an integrated model of systemic transcriptome (2969 genes) and metabolome (41 metabolites) response within placental cells exposed to high glucose. The functional pathways which demonstrated significant change in response to high glucose included fatty acid β-oxidation, phospholipid metabolism and phosphatidylinositol phosphate signalling.

Exploring and visualizing multidimensional data in translational research platforms

The unprecedented advances in technology and scientific research over the past few years have provided the scientific community with new and more complex forms of data. Large data sets collected from single groups or cross-institution consortiums containing hundreds of omic and clinical variables corresponding to thousands of patients are becoming increasingly commonplace in the research setting. Before any core analyses are performed, visualization often plays a key role in the initial phases of research, especially for projects where no initial hypotheses are dominant. Proper visualization of data at a high level facilitates researcher's abilities to find trends, identify outliers and perform quality checks. In addition, research has uncovered the important role of visualization in data analysis and its implied benefits facilitating our understanding of disease and ultimately improving patient care. In this work, we present a review of the current landscape of existing tools designed to facilitate the visualization of multidimensional data in translational research platforms. Specifically, we reviewed the biomedical literature for translational platforms allowing the visualization and exploration of clinical and omics data, and identified 11 platforms: cBioPortal, interactive genomics patient stratification explorer, Igloo-Plot, The Georgetown Database of Cancer Plus, tranSMART, an unnamed data-cube-based model supporting heterogeneous data, Papilio, Caleydo Domino, Qlucore Omics, Oracle Health Sciences Translational Research Center and OmicsOffice® powered by TIBCO Spotfire. In a health sector continuously witnessing an increase in data from multifarious sources, visualization tools used to better grasp these data will grow in their importance, and we believe our work will be useful in guiding investigators in similar situations.

In-season changes in heart rate recovery are inversely related to time to exhaustion but not aerobic capacity in rowers

To determine if in-season changes in heart rate recovery (HRR) are related to aerobic fitness and performance in collegiate rowers. Twenty-two female collegiate rowers completed testing before and after their competitive season. Body fat percentage (BF%) was determined by dual-energy X-ray absorptiometry. Maximal aerobic capacity (VO_2max ) and time to exhaustion (T_max ) were determined during maximal rowing ergometer testing followed by 1 minute of recovery. HRR was expressed absolutely and as a percentage of maximal HR (HRR%_1 min ). Variables were compared using paired Wilcoxon tests. Multivariable regression models were used to predict in-season changes in HRR using changes in VO_2max and T_max , while accounting for changes in BF%. From preseason to post-season, VO_2max and BF% decreased (3.98±0.42 vs 3.78±0.35 L/min, P=.002 and 23.8±3.4 vs 21.3±3.9%, P<.001, respectively), while T_max increased (11.7±1.3 vs 12.6±1.3 min, P=.002), and HRR%_1 min increased (11.1±2.7 vs 13.8±3.8, P=.001). In-season changes in VO_2max were not associated with HRR%_1 min (P>.05). In-season changes in T_max were related to changes in HRR%_1 min (β=-1.67, P=.006). In-season changes in BF% were not related to changes in HRR (P>.05 for all). HRR_1 min and HRR%_1 min were faster preseason to post-season, although the changes were unrelated to VO_2max . Faster HRR%_1 min post-season was inversely related to changes in T_max . This suggests that HRR should not be used as a measure of aerobic capacity in collegiate rowers, but is a promising measure of training status in this population.

Multimodal Interventions to Enhance Adherence to Secondary Preventive Medication after Stroke: A Systematic Review and Meta-Analyses

INTRODUCTION

Nonadherence to secondary preventative medications after stroke is common and is associated with poor outcomes. Numerous strategies exist to promote adherence. We performed a systematic review and meta-analysis to describe the efficacy of strategies to improve adherence to stroke secondary prevention.

METHODS

We created a sensitive search strategy and searched multiple electronic databases (MEDLINE, EMBASE, CINAHL, PsycINFO, CENTRAL, and Web of Knowledge) for studies of interventions that aimed to enhance adherence to secondary preventative medication after stroke. We assessed quality of included studies using the Cochrane tool for assessing risk of bias. We performed narrative review and performed meta-analysis where data allowed.

RESULTS

From 12,237 titles, we included seventeen studies in our review. Eleven studies were considered to have high risk of bias, 3 with unclear risk, and 3 of low risk. Meta-analysis of available data suggested that these interventions improved adherence to individual medication classes (blood pressure-lowering drugs - OR, 2.21; 95% CI (1.63, 2.98), [P < 0.001], lipid-lowering drugs - OR, 2.11; 95% CI (1.00, 4.46), [P = 0.049], and antithrombotic drugs - OR, 2.32; 95% CI (1.18, 4.56, [P = 0.014]) but did not improve adherence to an overall secondary preventative medication regimen (OR, 1.96; 95% CI (0.50, 7.67), [P = 0.332]).

CONCLUSION

Interventions can lead to improvement in adherence to secondary preventative medication after stroke. However, existing data is limited as several interventions, duration of follow-up, and various definitions were used. These findings need to be interpreted with caution.

Classifying sensory profiles of children in the general population

BACKGROUND

The aim of this study was to subtype groups of children in a community sample with and without developmental conditions, based on sensory processing patterns.

METHODS

We used latent profile analysis to determine the number of sensory subtypes in a sample of n = 1132 children aged 3-14 years with typical development and developmental conditions, including autism spectrum disorder (ASD), attention-deficit hyperactivity disorder and learning disabilities.

RESULTS

A five-subtype solution was found to best characterize the sample, which differed on overall degree and differential presentation of sensory processing patterns. Children with and without developmental conditions presented across subtypes, and one subtype was significantly younger in age than others (P < 0.05).

CONCLUSIONS

Our results show that sensory subtypes include both children with typical development and those with developmental conditions. Sensory subtypes have previously been investigated in ASD only, and our results suggest that similar sensory subtypes are present in a sample reflective of the general population of children including those largely with typical development. Elevated scores on sensory processing patterns are not unique to ASD but rather are reflections of children's abilities to respond to environmental demands.

Simulation, Mastery Learning and Healthcare

Healthcare organizations, becoming increasingly complex, need to use simulation techniques as a tool to provide consistently safe care. Mastery learning techniques minimize variation in learner outcome, thus improving the consistency and cost-effectiveness of care. Today׳s organizations (and their teams of decision makers) exist within varying states of transformation. These transformational times afford opportunities to use mastery learning concepts at an organizational level and to affect necessary change(s). Evolving technologies, including simulation, have provided mechanisms to enhance system performance, reducing reliance on custom-built "problem-solving" solutions for individual system needs. As such, simulation has emerged as an increasingly necessary organizational tool in improving value-driven, consistent processes of care. Both computer-based and non-computer-based algorithms of healthcare simulations offer distinct advantages in improving system performance over traditional methods of quality improvement. Simulation as a process engineering tool, integrated with mastery learning techniques, provides powerful platforms for improving value-based care.

explICU: A web-based visualization and predictive modeling toolkit for mortality in intensive care patients

Preventing mortality in intensive care units (ICUs) has been a top priority in American hospitals. Predictive modeling has been shown to be effective in prediction of mortality based upon data from patients' past medical histories from electronic health records (EHRs). Furthermore, visualization of timeline events is imperative in the ICU setting in order to quickly identify trends in patient histories that may lead to mortality. With the increasing adoption of EHRs, a wealth of medical data is becoming increasingly available for secondary uses such as data exploration and predictive modeling. While data exploration and predictive modeling are useful for finding risk factors in ICU patients, the process is time consuming and requires a high level of computer programming ability. We propose explICU, a web service that hosts EHR data, displays timelines of patient events based upon user-specified preferences, performs predictive modeling in the back end, and displays results to the user via intuitive, interactive visualizations.

Predictive factors of non-adherence to secondary preventative medication after stroke or transient ischaemic attack: A systematic review and meta-analyses

Purpose

Non-adherence to secondary preventative medications after stroke is relatively common and associated with poorer outcomes. Non-adherence can be due to a number of patient, disease, medication or institutional factors. The aim of this review was to identify factors associated with non-adherence after stroke.

Method

We performed a systematic review and meta-analysis of studies reporting factors associated with medication adherence after stroke. We searched MEDLINE, EMBASE, CINAHL, PsycINFO, CENTRAL and Web of Knowledge. We followed PRISMA guidance. We assessed risk of bias of included studies using a pre-specified tool based on Cochrane guidance and the Newcastle–Ottawa scales. Where data allowed, we evaluated summary prevalence of non-adherence and association of factors commonly reported with medication adherence in included studies using random-effects model meta-analysis.

Findings

From 12,237 titles, we included 29 studies in our review. These included 69,137 patients. The majority of included studies (27/29) were considered to be at high risk of bias mainly due to performance bias. Non-adherence rate to secondary preventative medication reported by included studies was 30.9% (95% CI 26.8%–35.3%). Although many factors were reported as related to adherence in individual studies, on meta-analysis, absent history of atrial fibrillation (OR 1.02, 95% CI 0.72–1.5), disability (OR 1.27, 95% CI 0.93–1.72), polypharmacy (OR 1.29, 95% CI 0.9–1.9) and age (OR 1.04, 95% CI 0.96–1.14) were not associated with adherence.

Discussion

This review identified many factors related to adherence to preventative medications after stroke of which many are modifiable. Commonly reported factors included concerns about treatment, lack of support with medication intake, polypharmacy, increased disability and having more severe stroke.

Conclusion

Understanding factors associated with medication taking could inform strategies to improve adherence. Further research should assess whether interventions to promote adherence also improve outcomes.

Abstract TP430: Interventions to Enhance Adherence to Secondary Preventative Medication After Stroke a Systematic Review and Meta-Analysis

Background and Purpose: Non-adherence to secondary preventative medications after stroke is common. Numerous strategies exist to promote adherence and we performed a systematic review and meta-analysis of these strategies after stroke.

Methods: We systematically reviewed MEDLINE, EMBASE, CINAHL, PsycINFO, Cochrane Databases, and the Web of Knowledge for studies of interventions to enhance adherence to secondary preventative medication after stroke. We followed PRISMA guidance. We performed meta-analysis where data allowed.

Results: We carried out the search in March - April 2014 and identified a total of 12,237 titles. Title review identified 143 papers for abstract review, 57 were retrieved for full-text review and 17 met our eligibility criteria. The total number of participants enrolled was 3942 patients with stroke/TIA (2090 participants were finally analysed in the intervention group and 824 participants as controls). We separated findings of included studies depending on secondary preventative medication classes reported. In the meta-analyses, we included three studies reported the effect of intervention to the overall secondary preventative medications regimen, six studies effect of intervention reported adherence to blood-pressure lowering drugs , and three studies reported effect of intervention on adherence to lipid-lowering drugs . There was no sufficient number of studies reported adherence to antithrombotic drugs after stroke. Forest-plots were constructed for each analysis (figure).

Conclusion: Interventions in identified studies lead to improvement in adherence to secondary preventative medication after stroke. However, existing data is limited thus need to be interpreted with caution.

Figure: Forest plots of meta-analyses of intervention studies (Favours A = Control, Favours B = Intervention)

Dysregulated autophagy in the RPE is associated with increased susceptibility to oxidative stress and AMD

Autophagic dysregulation has been suggested in a broad range of neurodegenerative diseases including age-related macular degeneration (AMD). To test whether the autophagy pathway plays a critical role to protect retinal pigmented epithelial (RPE) cells against oxidative stress, we exposed ARPE-19 and primary cultured human RPE cells to both acute (3 and 24 h) and chronic (14 d) oxidative stress and monitored autophagy by western blot, PCR, and autophagosome counts in the presence or absence of autophagy modulators. Acute oxidative stress led to a marked increase in autophagy in the RPE, whereas autophagy was reduced under chronic oxidative stress. Upregulation of autophagy by rapamycin decreased oxidative stress-induced generation of reactive oxygen species (ROS), whereas inhibition of autophagy by 3-methyladenine (3-MA) or by knockdown of ATG7 or BECN1 increased ROS generation, exacerbated oxidative stress-induced reduction of mitochondrial activity, reduced cell viability, and increased lipofuscin. Examination of control human donor specimens and mice demonstrated an age-related increase in autophagosome numbers and expression of autophagy proteins. However, autophagy proteins, autophagosomes, and autophagy flux were significantly reduced in tissue from human donor AMD eyes and 2 animal models of AMD. In conclusion, our data confirm that autophagy plays an important role in protection of the RPE against oxidative stress and lipofuscin accumulation and that impairment of autophagy is likely to exacerbate oxidative stress and contribute to the pathogenesis of AMD.

Abstract 415: Differential expression of therapeutic targets across tumor micro-environments and at infiltrative margins in glioblastoma

Glioblastoma (GBM; WHO grade IV) is the most common primary brain tumor and is associated with a poor prognosis. The Cancer Genome Atlas (TCGA) project has revealed discrete molecular classes of GBM, raising the possibility of targeted therapies. Molecular heterogeneity across tumor microenvironments presents a challenge to targeted therapy, since effective therapies will be directed at targets near resection margins rather than those expressed in bulk resected tumor. To this end, we initiated studies to delineate spatial and temporal variations of potential druggable targets in GBM, focusing on potential protein targets at the tumor margin.

By utilizing 5-ALA (5-aminolevulinic acid, an oral compound that accumulates in malignant glioma cells and is metabolized to the fluorescent agent, protoporphyrin IX) fluorescence-guided surgery of primary and recurrent GBMs in a Phase II clinical trial, we were able to precisely define perinecrotic, bulk, and marginal regions within the glioma intraoperatively in order to sample tissues for further molecular characterization. Tissues harvested from these 3 tumor regions from 5 patients were analyzed using reverse phase protein array (RPPA) analysis with 218 antibodies (Array-Pro). Relative protein levels were determined and a heatmap was generated as a hierarchical cluster using Pearson Correlation and a center metric.

Forty proteins had statistically significant altered expression at the tumor margin compared with bulk and perinecrotic tumor. Among these, STAT1, STAT2, STAT3, PDGFRA, PDGFRB, EGFR, JAK2, MET, PIK3R1, and ERBB2 were upregulated at the margins and are potential druggable targets worthy of further investigation. Also upregulated at the tumor margins were NFKBIA, JUN, ZAP70, GAPDH, and CD28, whereas STAT5A, EFNB2, NTRK1, KDR, FGFR1, PTPRA, IFNGR1, and EFNB1 were downregulated at margins.

Our data demonstrate significant variation of druggable targets and signaling networks across tumor microenvironments in GBM. Marginal tumor differs from bulk and perinecrotic tumor by the relative overexpression of STAT proteins, growth factor receptors, and receptor kinases. Directing therapy at networks and targets present at the tumor margin of GBM may be an effective strategy.

Citation Format: Myles R. McCrary, David Gutman, William Dunn, Milota Kaluzova, Alexandros Bouros, Merete Williams, Xialong Zhang, Lee AD Cooper, Constantinos G. Hadjipanayis, Daniel J. Brat. Differential expression of therapeutic targets across tumor micro-environments and at infiltrative margins in glioblastoma. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 415. doi:10.1158/1538-7445.AM2015-415

Porphyromonas gingivalis strain specific interactions with human coronary artery endothelial cells: a comparative study

Both epidemiologic and experimental findings suggest that infection with Porphyromonas gingivalis exacerbates progression of atherosclerosis. As P. gingivalis exhibits significant strain variation, it is reasonable that different strains possess different capabilities and/or mechanisms by which they promote atherosclerosis. Using P. gingivalis strains that have been previously evaluated in the ApoE null atherosclerosis model, we assessed the ability of W83, A7436, 381, and 33277 to adhere, invade, and persist in human coronary artery endothelial (HCAE) cells. W83 and 381 displayed an equivalent ability to adhere to HCAE cells, which was significantly greater than both A7436 and 33277 (P<0.01). W83, 381, and 33277 were more invasive than A7436 (P<0.0001). However, only W83 and A7436 were able to remain viable up to 48 hours in HCAE cell cultures, whereas 381 was cleared by 48 hours and 33277 was cleared by 24 hours. These differences in persistence were in part due to strain specific differences in intracellular trafficking. Both W83 and 381 trafficked through the autophagic pathway, but not A7436 or 33277. Internalized 381 was the only strain that was dependent upon the autophagic pathway for its survival. Finally, we assessed the efficacy of these strains to activate HCAE cells as defined by production of IL-6, IL-8, IL-12p40, MCP-1, RANTES, TNF-α, and soluble adhesion molecules (sICAM-1, sVCAM-1, and sE-selectin). Only moderate inflammation was observed in cells infected with either W83 or A7436, whereas cells infected with 381 exhibited the most profound inflammation, followed by cells infected with 33277. These results demonstrate that virulence mechanisms among different P. gingivalis strains are varied and that pathogenic mechanisms identified for one strain are not necessarily applicable to other strains.

Non-alcoholic fatty liver disease is associated with low bone mineral density in obese children

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease in children. Liver disease can be a cause of low bone mineral density. Whether or not NAFLD influences bone health is not known.

AIM

To evaluate bone mineral density in obese children with and without NAFLD.

METHODS

Thirty-eight children with biopsy-proven NAFLD were matched for age, gender, race, ethnicity, height and weight to children without evidence of liver disease from the National Health and Nutrition Examination Survey. Bone mineral density was measured by dual energy X-ray absorptiometry. Age and gender-specific bone mineral density Z-scores were calculated and compared between children with and without NAFLD. After controlling for age, gender, race, ethnicity and total per cent body fat, the relationship between bone mineral density and the severity of histology was analysed in children with NAFLD.

RESULTS

Obese children with NAFLD had significantly (P < 0.0001) lower bone mineral density Z-scores (-1.98) than obese children without NAFLD (0.48). Forty-five per cent of children with NAFLD had low-bone mineral density for age, compared to none of the children without NAFLD (P < 0.0001). Among those children with NAFLD, children with NASH had a significantly (P < 0.05) lower bone mineral density Z-score (-2.37) than children with NAFLD who did not have NASH (-1.58).

CONCLUSIONS

The NAFLD was associated with poor bone health in obese children. More severe disease was associated with lower bone mineralisation. Further studies are needed to evaluate the underlying mechanisms and consequences of poor bone mineralisation in children with NAFLD.

P3-09-02: Intermittent Dietary Carbohydrate Restriction Enables Weight Loss and Reduces Breast Cancer Risk Biomarkers

Background: Energy restriction is a potential strategy for breast cancer prevention but is difficult to achieve and maintain. We found that intermittent energy restriction (2 days strict dieting week) is comparable to the standard approach of moderate daily restriction for weight loss and marginally better for improving insulin sensitivity, but no easier to follow1. In this follow on study we wished to test whether 2 novel intermittent low carbohydrate/low energy diets were feasible and easier to follow than a standard daily energy restriction. Design: Randomised comparison of 3 dietary types over 4 months in 115 overweight or obese (mean body mass index 31.0 [±5.3 SD] kg/m2) women at increased risk of breast cancer (lifetime risk &gt; 1 in 6).

Diets:

1. A restricted low carbohydrate diet (RLCD): 650 kcal and &lt;50g carbohydrate / day for 2 days per week

2. Ad lib low carbohydrate diet (ALCD): &lt;50g / day for 2 days per week with other food types (e.g. protein) ad lib

3. A standard daily restricted Mediterranean diet (DRMD): ∼ 1500kcal/day for 7 days per week

Methods: Weight, anthropometrics, blood markers for breast cancer; insulin resistance, oxidative stress markers, leptin, adiponectin, lipids, inflammatory markers IGF-1 were assessed at baseline, 1, 3 and 4 months.

Results: 88/114 completed the study (77%, drop outs 6 RLCD, 8 ALCD 12 DRMD). Last observation carried forward analyses show both intermittent low carbohydrate diets were superior to standard daily restriction for reducing weight and body fat: mean (95% confidence interval [CI]) change in body fat for RLCD was −4.3 (−5.6 to −3.0) kg, for ALCD −4.1 (−5.2 to −3.1) kg vs. −2.4 (−3.4 to −1.2) kg for DRMD (P value for difference between groups = 0.02). The intermittent groups had greater improvement in insulin resistance: mean (95% CI) change for RLCD was −22 (−35 to −11) %, ALCD −14 (−27 to −5%) % vs. −4 (−16 to 9) % for DRMD (P = 0.02). Other biomarkers are being assayed currently.

Conclusion: Greater weight loss, fewer drop outs and greater reductions in insulin resistance with the novel intermittent low carbohydrate diets indicate that these are alternative approaches for energy restriction for potentially reducing risk of breast cancer and other diseases.

Reference:

1Harvie MN, Pegington M, Mattson MP, Frystyk J, Dillon B, Evans G et al. The effects of intermittent or continuous energy restriction on weight loss and metabolic disease risk markers: a randomized trial in young overweight women. Int.J Obes (Lond) 35; 714–27, 2011. This study is funded by the Genesis Breast Cancer Prevention Appeal: www.genesisuk.org

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P3-09-02.

Porphyromonas gingivalis and the autophagic pathway: an innate immune interaction?

Autophagy is a mechanism used to maintain several intracellular functions essential to eukaryotic cells. Recently, a role for autophagy in innate and adaptive immunity has also been established including the elimination of invading bacteria. Although some intracellular pathogens are killed by autophagy, several others subvert autophagy to the pathogen's benefit for survival and replication. Porphyromonas gingivalis, an important periodontal pathogen, has been shown to stimulate autophagy in endothelial cells and to use the autophagic pathway to its advantage. In human coronary artery endothelial cells (HCAEC), P. gingivalis localizes within autophagosomes. After intracellular uptake, P. gingivalis transits from early autophagosomes to late autophagosomes and prevents the formation of autolysosomes, either by delaying the autophagosome-lysosome fusion or by redirecting the normal autophagic trafficking. In addition, P. gingivalis was also found to stimulate autophagy in human aortic endothelial cells (HAEC) since co-localization of LC3-II, an autophagosome marker, with P. gingivalis was observed. The trafficking of P. gingivalis into the autophagic pathway appears to be dependent upon the host cell type. Survival of P. gingivalis through the subversion of the host autophagic pathway can be considered a bacterial strategy to evade the innate immune system and persist in the host.

The Porphyromonas gingivalis clpB gene is involved in cellular invasion in vitro and virulence in vivo

ClpB, a component of stress response in microorganisms, serves as a chaperone, preventing protein aggregation and assisting in the refolding of denatured proteins. A clpB mutant of Porphyromonas gingivalis W83 demonstrated increased sensitivity to heat stress, but not to hydrogen peroxide and extreme pHs. In KB cells, human coronary artery endothelial (HCAE) cells and gingival epithelial cells, the clpB mutant exhibited significantly decreased invasion suggesting that the ClpB protein is involved in cellular invasion. Transmission electron microscopic analysis showed that the clpB mutant was more susceptible to intracellular killing than the wild-type strain in HCAE cells. The global genetic profile of the clpB mutant showed that 136 genes belonging to several different cellular function groups were differentially regulated, suggesting that ClpB is ultimately involved in the expression of multiple P. gingivalis genes. A competition assay in which a mixture of wild-type W83 and the clpB mutant were injected into mice demonstrated that the clpB mutant did not survive as well as the wild type. Additionally, mice treated with the clpB mutant alone survived significantly better than those treated with the wild-type strain. Collectively, these data suggest that ClpB, either directly or indirectly, plays an important role in P. gingivalis virulence.

Is simulation based medicine training the future of clinical medicine?

The training of physician in the art and science of clinical medicine presents several challenges that are well suited to simulation based medical education (SBME). Modern patient centered medical education seeks to provide comprehensive "hands-on" clinical exposure for physicians in training, while simultaneously providing maximum individual patient comfort and safety. The ethical conundrum is obvious: direct patient contact is needed in order to educate the best clinical physicians and surgeons, but patients have an expectation to be treated and have surgery performed only by highly trained healthcare personnel. This is the kernel of the "medical educators dilemma". Simulation based medical education can partially solve "the medical educators dilemma" by providing realistic medical education in a safe, error tolerant environment with convenience and advantages over conventional "bedside" training but is it real medicine or make believe!

MRI screening before standard tissue plasminogen activator therapy is feasible and safe

BACKGROUND AND PURPOSE

MRI screening for thrombolytic therapy may improve patient selection. Alternatively, it may excessively delay treatment and thereby lead to worse outcomes. We hypothesized that times to treatment and outcomes in a stroke center with immediate MRI access and interpretation would not differ from those of the typical clinical practice.

METHODS

We compared the results of 120 consecutive patients treated with intravenous tissue plasminogen activator (tPA) within 3 hours of onset at our center with those of the 2 largest multicenter registries of tPA use. In addition to standard criteria, MRI specific eligibility criteria were applied in 97 patients. MRI was not performed in 23 patients because of contraindications to MRI or late patient arrival (>2.5 hours). Outcomes were the modified Rankin Scale (mRS) obtained at 3 months.

RESULTS

Times to treatment (median door-to-needle time 81.5 minutes; median onset-to-needle time 135 minutes) and outcomes (mRS 0 to 1, 40.8%; mRS 0 to 2, 47.5%) were not inferior to those of the typical clinical practice. Door-to-needle time was shorter in computed tomography (CT) screening (67.5+/-22.5 minutes; n=23) than in MRI screening (86.8+/-21.5 minutes; n=97; P<0.001). However, outcomes were not different between MRI screening (mRS 0 to 1, 42.3%; mRS 0 to 2, 49.5%) and CT screening (mRS 0 to 1, 34.8%; mRS 0 to 2, 39.1%). Neither times to treatment nor MRI screening was predictive of outcomes.

CONCLUSIONS

These data demonstrate that MRI screening before tPA therapy is feasible and not associated with unacceptable times to treatment or outcomes.

Antinociceptive properties of oxymorphazole in the mouse

Oxymorphazole (17-methyl-6,7-dehydro-3,14-dihydroxy-4,5 alpha-epoxy-6,7:3',4'-pyrazolomorphinan), a hydrophilic opioid, given intracerebroventricularly (2.5-50 nmol) or intrathecally (0.3-5 nmol) dose-dependently produced tail-flick inhibition in male CD-1 mice. However, oxymorphazole given subcutaneously even at high doses (10-80 mg/kg) produced weak tail-flick inhibition. Oxymorphazole given intraperitoneally (0.1 to 10 mg/kg) dose-dependently inhibited abdominal constriction response induced by intraperitoneally injection of 0.6% acetic acid. Oxymorphazole given intracerebroventricularly (25 nmol) or intrathecally (5 nmol) induced tail-flick inhibition was blocked by pretreatment with the mu-opioid receptor antagonist D-Phe-Cys-Tyr-D-Orn-Thr-Pen-Thr-NH2, but not kappa-opioid receptor antagonist nor-binaltrophimine. The delta-opioid receptor antagonist, naltrindole, blocked the tail-flick inhibition induced by oxymorphazole given intrathecally but not intracerebroventricularly. The inhibition of the abdominal constriction response by oxymorphazole given intraperitoneally was blocked by intraperitoneally pretreatment with naloxone, but not naltrindole or nor-binaltrophimine. Thus, oxymorphazole given systemically produces antinociception only with the abdominal constriction test, but not the tail-flick test, suggesting that it produces the antinociception at the peripheral sites when administered systemically. The oxymorphazole-induced antinociception is mainly mediated by the stimulation of mu-opioid receptors when given either centrally or systemically and also the delta-opioid receptors when given intrathecally. The lack of central antinociceptive effect of oxymorphazole given systemically may have interesting clinical implications.

A comparison of shear bond strengths of orthodontic brackets using various light sources, light guides, and cure times

The objective of this study was to evaluate the effects of different cure times, light sources, and light guides on shear bond strength of orthodontic brackets bonded with Transbond XT (3M Unitek, Monrovia, Calif) to bovine enamel. Specifically, the Power Slot (Reliance Orthodontic Products, Itasca, Ill) light guide was placed on 4 visible light sources to compare shear bond strengths and recommended cure times with the light guides provided with each light source. We randomly divided 240 bovine mandibular incisors into 16 groups; each group consisted of 15 teeth mounted in an acrylic block. Each group of teeth was polymerized with a specific light and light guide combination. Eight groups were sheared after 5 minutes and the remaining 8 groups after 24 hours. After bonding, all brackets were subjected to a shear force with a testing machine. Overall, there was a significant increase in bond strengths of the 24-hour groups compared with the 5-minute shearing groups. However, there were no statistical differences (P =.05) within the 24-hour test groups or the 5-minute test groups. The results of this study indicate that, compared with standard light guides, the Power Slot and the Turbo Tip (Ormco Sybron Dental Specialties, Orange, Calif) light guides can significantly reduce the curing times (10 seconds per bracket; 5 seconds each from mesial and distal) without affecting their shear bond strengths. Therefore, the Power Slot and the Turbo Tip light guides with their collimation of visible light to increase its intensity can be recommended as advantageous alternatives for curing composite resins for orthodontic bonding procedures.

Intranasal administration of naloxone by paramedics

INTRODUCTION

Naloxone is a medication that is frequently administered in the field by paramedics for suspected opioid overdoses. Most prehospital protocols, however, require this medication to be given to patients intravenously (i.v.) or intramuscularly (i.m.). Unfortunately, intravenous line placement may be problematic and time-consuming in chronic i.v. drug users. There may also be a delay in patient response to opioid reversal with i.m. absorption of naloxone. Additionally, routine use of needles in high-risk populations poses an increased risk of occupational blood exposures to paramedics.

OBJECTIVE

To prospectively test the effectiveness of intranasal (i.n.) naloxone administration by paramedics. This preliminary report summarizes the first month's experience in the city of Denver.

METHODS

Naloxone was first administered to patients found unconscious in the field using a nasal mucosal atomizer device (MAD). Patients were then treated using standard prehospital protocols, which included i.v. line placement and medications, if they did not immediately respond to i.n. naloxone. Time to patient response was recorded.

RESULTS

A total of 30 patients received i.n. naloxone in the field over a one-month period. Of these, 11 patients responded to either i.n. or i.v. naloxone. Ten (91%) patients responded to i.n. naloxone alone, with an average response time of 3.4 minutes. Seven patients (64%) did not require an i.v. in the field after response to i.n. naloxone.

CONCLUSIONS

Intranasal naloxone may provide a safe, rapid, effective way to manage suspected opioid overdoses in the field. Use of this route may decrease paramedic exposures to blood-borne diseases. The addition of i.n. naloxone administration to prehospital protocols should be considered as an initial therapy for suspected opioid abusers.

RNase P-mediated inhibition of cytomegalovirus protease expression and viral DNA encapsidation by oligonucleotide external guide sequences

External guide sequences (EGSs) are oligonucleotides that consist of a sequence complementary to a target mRNA and recruit intracellular RNase P for specific degradation of the target RNA. In this study, DNA-based EGS molecules were chemically synthesized to target the mRNA coding for the protease of human cytomegalovirus (HCMV). The EGS molecules efficiently directed human RNase P to cleave the target mRNA sequence in vitro. When EGSs were exogenously administered into HCMV-infected human foreskin fibroblasts, a reduction of about 80-90% in the expression level of the protease and a reduction of about 300-fold in HCMV growth were observed in the cells that were treated with a functional EGS, but not in cells that were not treated with the EGS or with a "disabled" EGS carrying nucleotide mutations that precluded RNase P recognition. Moreover, packaging of the viral DNA genome into the capsid was blocked in the cells treated with the functional EGS. These results indicate that HCMV protease is essential for viral DNA encapsidation. Moreover, our study provides direct evidence that exogenous administration of a DNA-based EGS can be used as a therapeutic approach for inhibiting gene expression and replication of a human virus.

The sensations of everyday life: empirical, theoretical, and pragmatic considerations

The experience of being human is embedded in sensory events of everyday life. This lecture reviews sensory processing literature, including neuroscience and social science perspectives. Introduced is Dunns Model of Sensory Processing, and the evidence supporting this model is summarized. Specifically, using Sensory Profile questionnaires (i.e., items describing responses to sensory events in daily life; persons mark the frequency of each behavior), persons birth to 90 years of age demonstrate four sensory processing patterns: sensory seeking, sensory avoiding, sensory sensitivity, and low registration. These patterns are based on a persons neurological thresholds and self-regulation strategies. Psychophysiology studies verify these sensory processing patterns; persons with strong preferences in each pattern also have unique patterns of habituation and responsivity in skin conductance. Studies also indicate that persons with disabilities respond differently than peers on these questionnaires, suggesting underlying poor sensory processing in certain disorders, including autism, attention deficit hyperactivity disorder, developmental delays, and schizophrenia. The author proposes relationships between sensory processing and temperament and personality traits. The four categories of temperament share some consistency with the four sensory processing patterns described in Dunn's model. As with temperament, each person has some level of responsiveness within each sensory processing preference (i.e., a certain amount of seeking, avoiding, etc., not one or the other). The author suggests that one's sensory processing preferences simultaneously reflect his or her nervous system needs and form the basis for the manifestation of temperament and personality. The final section of this lecture outlines parameters for developing best practice that supports interventions based on this knowledge.

The source and abatement of nitrous oxide emissions produced from the aerobic treatment of pig slurry to remove surplus nitrogen

The removal of surplus nitrogen from pig slurry can be necessary in order to avoid pollution such as nitrate leaching. However, the treatment itself can create significant pollution; up to 20% of the removed slurry nitrogen has been shown to be released as nitrous oxide (N2O), which contributes to global warming and the breakdown of the ozone in the stratosphere. Avoiding such emission requires conditions that encourage the complete conversion of the nitrogen to the environmentally safe di-nitrogen gas (N2), and a clear understanding of the underlying biochemistry; for example, whether the nitrous oxide is the bi-product of incomplete nitrification (chemical oxidation) or denitrification (chemical reduction). The stable isotope of nitrogen ( N) was used in this investigation as a label. Results indicated a new route for substantial release of N2O: via nitrification (rather than denitrification), caused by a combination of high aeration levels and the presence of nitrification products. Sequential aeration, which leads to a cycling between nitrification and complete denitrification, was proposed as an abatement in view of this new mechanism. This process achieved 89% removal of ammoniacal nitrogen in laboratory scale treatment, with 94% of the nitrogen removed in the form of N2. These findings suggest that the possibility of N2O emissions from nitrification be considered in the design of treatment schemes. Increased aeration would be the intuitive response to incomplete nitrification. However, the results of this study suggested that although this response can increase nitrogen removal, this may be as N2O rather than N2.

The Adult Sensory Profile: measuring patterns of sensory processing

OBJECTIVE

This article describes a series of studies designed to evaluate the reliability and validity of the Adult Sensory Profile.

METHOD

Expert judges evaluated the construct validity of the items. Coefficient alpha, factor analysis, and correlations of items with subscales determined item reliability, using data from 615 adult sensory profiles. A subsample of 20 adults furnished skin conductance data. A heterogeneous group of 93 adults completed the revised Adult Sensory Profile, and item reliability was reexamined.

RESULTS

Expert judgment indicated that items could be categorized according to Dunn's Model of Sensory Processing. Results suggested reasonable item reliability for all subscales except for the Sensation Avoiding subscale. Skin conductance measures detected distinct patterns of physiological responses consistent with the four-quadrant model. Revision of the Adult Sensory Profile resulted in improved reliability of the Sensation Avoiding subscale.

CONCLUSION

The series of studies provides evidence to support the four subscales of the Adult Sensory Profile as distinct constructs of sensory processing preferences.

Murine cytomegalovirus containing a mutation at open reading frame M37 is severely attenuated in growth and virulence in vivo

A pool of murine cytomegalovirus (MCMV) mutants was generated by using a Tn3-based transposon mutagenesis procedure. One of the mutants, RvM37, which contained the transposon sequence at open reading frame M37, was characterized both in tissue culture and in immunocompetent BALB/c and immunodeficient SCID mice. Our results provide the first direct evidence to suggest that M37 is not essential for viral replication in vitro in NIH 3T3 cells. Compared to the wild-type strain and a rescued virus that restored the M37 region, the viral mutant was severely attenuated in growth in both BALB/c and SCID mice after intraperitoneal infection. Specifically, titers of the Smith strain and rescued virus in the salivary glands, lungs, spleens, livers, and kidneys of the SCID mice at 21 days postinfection were about 5 x 10(5), 2 x 10(5), 5 x 10(4), 5 x 10(3), and 1 x 10(4) PFU/ml of organ homogenate, respectively; in contrast, titers of RvM37 in these organs were less than 10(2) PFU/ml of organ homogenate. Moreover, the virulence of the mutant virus appeared to be significantly attenuated because none of the SCID mice infected with RvM37 had died by 120 days postinfection, while all animals infected with the wild-type and rescued viruses had died by 26 days postinfection. Our results suggest that M37 probably encodes a virulence factor and is required for MCMV virulence in SCID mice and for optimal viral growth in vivo.

Visual outcome following penetrating globe injuries with retained intraocular foreign bodies

BACKGROUND

In our institution the occurrence of endophthalmitis related to intraocular foreign bodies has been rare. In this review we analyse the outcome of eyes with retained intraocular foreign bodies presenting to two vitreoretinal surgeons over nearly 7 years.

METHODS

Review of the records of 26 patients who presented to two surgeons in a tertiary care vitreoretinal service in Toronto between January 1989 and November 1995. Information documented included mechanism of injury, time from injury to definitive surgery, entry site, presence of vitreous hemorrhage, type of surgery performed, initial and final visual acuity, and development of endophthalmitis.

RESULTS

All the injuries occurred in male patients, with a mean age of 36.1 (range 15 to 55) years. Most of the injuries occurred in the workplace, and in most cases (17 [65.4%]) the mechanism of injury was "metal on metal." The entry site was via a perforating wound of the cornea in 16 cases (61.5%). Almost all cases were repaired within 48 hours by means of pars plana vitrectomy. Concurrent lensectomy was required in 18 cases (69.2%) for lens damage at the time of the original injury. Vitreous hemorrhage was present in 22 cases (84.6%). One patient (3.8%) manifested clinically apparent endophthalmitis, which responded to intravitreal antibiotic therapy. Nineteen eyes (73.1%) had a final visual acuity of 6/24 or better. Eyes with coexisting or subsequent retinal detachment had significantly worse vision than those without retinal detachment (p < 0.001).

INTERPRETATION

The incidence of endophthalmitis in our series is lower than that in other published series. Prompt definitive treatment was associated with a good prognosis in most cases.

Porphyromonas gingivalis virulence factors and invasion of cells of the cardiovascular system

Our laboratory is interested in the genes and gene products involved in the interactions between Porphyromonas gingivalis (Pg) and the host. These interactions may occur in either the periodontal tissues or other non-oral host tissues such as those of the cardiovascular system. We have previously reported the cloning of several genes encoding hemagglutinins, surface proteins that interact with the host tissues, and are investigating their roles in the disease process. Primary among these is HagA, a very large protein with multiple functional groups that have significant sequence homology to protease genes of this species. Preliminary evidence indicates that an avirulent Salmonella typhimurium strain containing hagA is virulent in mice. These data indicate that HagA may be a key virulence factor of Pg. Additionally, we are investigating the invasion of primary human coronary artery endothelial cells (HCAEC) by Pg because of the recent epidemiological studies indicating a correlation between periodontal disease (PD) and coronary heart disease (CHD). We found that some, but not all, strains of Pg are able to invade these cells. Scanning electron microsopy of the infected HCAEC demonstrated that the invading organisms initially attached to the host cell surface as aggregates and by a "pedestal"-like structure. By transmission electronmicroscopy it could be seen that internalized bacteria were present within multimembranous compartments localized with rough endoplasmic reticulum. In addition, invasion of the HCAEC by Pg resulted in an increase in the degradation of long-lived cellular proteins. These data indicate that Pg are present within autophagosomes and may use components of the autophagic pathway as a means to survive intracellularly. However, Pg presence within autophagosomes in KB cells could not be observed or detected. It is therefore likely that Pg uses different invasive mechanisms for different host cells. This and the role of HagA in invasion is currently being investigated further.

Immunization with amyloid-beta attenuates Alzheimer-disease-like pathology in the PDAPP mouse

Amyloid-beta peptide (Abeta) seems to have a central role in the neuropathology of Alzheimer's disease (AD). Familial forms of the disease have been linked to mutations in the amyloid precursor protein (APP) and the presenilin genes. Disease-linked mutations in these genes result in increased production of the 42-amino-acid form of the peptide (Abeta42), which is the predominant form found in the amyloid plaques of Alzheimer's disease. The PDAPP transgenic mouse, which overexpresses mutant human APP (in which the amino acid at position 717 is phenylalanine instead of the normal valine), progressively develops many of the neuropathological hallmarks of Alzheimer's disease in an age- and brain-region-dependent manner. In the present study, transgenic animals were immunized with Abeta42, either before the onset of AD-type neuropathologies (at 6 weeks of age) or at an older age (11 months), when amyloid-beta deposition and several of the subsequent neuropathological changes were well established. We report that immunization of the young animals essentially prevented the development of beta-amyloid-plaque formation, neuritic dystrophy and astrogliosis. Treatment of the older animals also markedly reduced the extent and progression of these AD-like neuropathologies. Our results raise the possibility that immunization with amyloid-beta may be effective in preventing and treating Alzheimer's disease.

The national occupational therapy practice analysis: findings and implications for competence

OBJECTIVE

This article reports some of the findings from a national study of occupational therapy practice conducted by the National Board for Certification in Occupational Therapy (NBCOT) as part of its fiduciary responsibility to ensure that its entry-level certification examination is formulated on the basis of current practice.

METHOD

The NBCOT developed a survey with input from approximately 200 occupational therapy leaders and then used it to solicit information about current practice from 4,000 occupational therapists and 3,000 occupational therapy assistants. The sample included geographical location, experience level, and practice area distributions.

RESULTS

Approximately 50% of the sample responded to the survey. Data indicate similarities and differences in occupational therapist and occupational therapy assistant practice (e.g., occupational therapists spend more time conducting evaluations, planning interventions, and supervising, whereas occupational therapy assistants spend more time providing interventions), an increased emphasis on population-based services (e.g., serving a business or industry rather than an individual worker), and an emphasis on occupation as a core knowledge base for practice. From a continuing competency perspective, the data can be useful to the profession; we can plan continuing education to address topics that practitioners have indicated are critical to their practice.

CONCLUSION

The findings will be useful for revising the entry-level certification examination and may guide thinking about the parameters of continuing competence because the responses represent a cross-section of the profession.

The sensory profile: a discriminant analysis of children with and without disabilities

OBJECTIVES

The purpose of this study was to determine which factors on the Sensory Profile, a measure of children's responses to commonly occurring sensory experiences, best discriminate among children with autism or pervasive developmental disorder (PDD), children with attention deficit hyperactivity disorder (ADHD), and children without disabilities.

METHOD

Data for three groups of children 3 to 15 years of age were used: 38 children with autism or PDD, 61 with ADHD, and 1,075 without disabilities. The researchers conducted a discriminate analysis on the three groups, using group membership as the dependent variable and the nine factors of the Sensory Profile as independent variables.

RESULTS

The analysis yielded two discriminant functions: one that differentiated children with disabilities from children without disabilities and another that differentiated the two groups of children with disabilities from each other. Nearly 90% of the cases were correctly classified with these two functions.

CONCLUSION

The Sensory Profile is useful for discriminating certain groups of children with disabilities. Children with disabilities are accurately classified into disability categories with the factors described by previous authors. This suggests that patterns of behavior associated with certain developmental disorders are reflected in populations of children without disabilities. It may be the frequency or intensity of certain behaviors that differentiate the groups.

A simulation of hand impairments: effects on upper extremity function and implications toward medical impairment rating and disability determination

OBJECTIVES

To determine whether simulation of significant impairment of the hand will have a predictable impact on degree of functional loss at the wrist and hand.

DESIGN

Single subject repeat measures using before-after trial comparisons and healthy volunteer subjects.

SETTING

Occupational therapy section of a large academic medical center.

OTHER PARTICIPANTS

Twenty adult volunteer student subjects from an occupational therapy education (OTE) department were included. All were between ages 18 and 43 years, right hand dominant, and in excellent general health. There were 19 women and 1 man, reflecting gender distribution of the OTE student body.

INTERVENTION

A simulated fusion of the carpometacarpal (CMC) joint of the thumb was achieved by immobilization in an individually fabricated splint designed to maximally restrict motion at the first CMC joint. Impairment ratings (baseline vs splinted) according to the AMA Guides were obtained by Greenleaf testing, and upper extremity function was quantitatively assessed before and after splinting.

MAIN OUTCOME MEASURES

Measures of upper extremity function included grip and pinch strength, wrist torque, and speed of performance on the Valpar Small Tools test, Jebsen Hand Function test, and an exploratory measure, the Functional Life Activity Test (FLAT).

RESULTS

Significant impairments were achieved for all subjects after splinting and according to Greenleaf testing. Splinting resulted in significant reductions in grip and pinch strength, wrist torque, and significant slowing of performance on the Valpar, Jebsen, and FLAT tests. Regressions of degree of impairment on degree of functional loss after splinting, and according to each of the above measures, were not significant.

CONCLUSIONS

Impairment of the hand was simulated to a mild-to-moderate degree as measured according to the AMA Guides. This imposed significant reductions in motion at key joints of the wrist and hand as well as significant reductions in grip and pinch strength and wrist torque. A corresponding and significant slowing of performance on a variety of measures of upper extremity function of an industrial and nonindustrial nature was also seen. However, and for the first time, correlation and regression reveals that it is not possible to predict degree of functional loss attributable to degree of impairment for the hand. It thus appears that, for mild-to-moderate clinical impairments, the associated impairment rating is a poor estimator of functional loss at the hand and should be used cautiously, if at all, as a criterion for disability determination.

A comparison of the performance of children with and without autism on the Sensory Profile

OBJECTIVE

The purpose of this study was to determine whether the Sensory Profile discriminates between children with and without autism and which items on the profile best discriminate between these groups.

METHOD

Parents of 32 children with autism aged 3 to 13 years and of 64 children without autism aged 3 to 10 years completed the Sensory Profile. A descriptive analysis of the data set of children with autism identified the distribution of responses on each item. A multivariate analysis of covariance (MANCOVA) of each category of the Sensory Profile identified possible differences among subjects without autism, with mild or moderate autism, and with severe autism. Follow-up univariate analyses were conducted for any category that yielded a significant result on the MANCOVA:

RESULTS

Eight-four of 99 items (85%) on the Sensory Profile differentiated the sensory processing skills of subjects with autism from those without autism. There were no group differences between subjects with mild or moderate autism and subjects with severe autism.

CONCLUSION

The Sensory Profile can provide information about the sensory processing skills of children with autism to assist occupational therapists in assessing and planning intervention for these children.