THE MAYAK WORKER DOSIMETRY SYSTEM (MWDS-2016): INTERNAL DOSIMETRY RESULTS AND COMPARISON WITH MWDS-2013

Differences in results from the new Mayak Worker Dosimetry System (MWDS-2016) vs the previous MWDS-2013 are described. Statistical characteristics are shown for the distribution of accumulated absorbed doses to organs for 8340 workers with bioassay data. Differences in mean values of accumulated doses and their relative standard uncertainties calculated by MWDS-2016 and MWDS-2013 were analysed separately for various types of industrial compounds of plutonium, specifically nitrates, mixtures and oxides. Within the range of accumulated doses >1 mGy, lung doses for nitrates and mixtures decreased by 41 and 15%, respectively, and remained at the same level for oxides. Accumulated liver doses within the range >1 mGy increased for nitrates and mixtures by 13 and 8%, respectively, and decreased for oxides by 7%.

An experimental investigation into cardiovascular, haemodynamic and salivary alpha amylase reactivity to acute stress in Type D individuals

Type D personality is characterized by increased social inhibition and negative affectivity. Research demonstrates associations between Type D and poor physical health. Maladaptive sympathetic arousal is suggested as a potential mechanism, however, findings are inconsistent and studies mainly focus on basic cardiovascular parameters. The current study examines cardiovascular and haemodynamic parameters in addition to salivary alpha amylase (sAA) as markers of sympathetic stress reactivity in Type D individuals. Healthy adults (N = 75; 33 Type D; aged 18-42; 64% female) completed a multitasking stressor while continuous beat-to-beat cardiovascular function was measured. Saliva samples were obtained at baseline, pre-task, post-task, +10 min and +20 min post-task. Type Ds exhibited dysfunctional cardiovascular reactivity, characterized by blunted total peripheral resistance, slower stroke volume recovery and potentially unhealthy changes in haemodynamic profile. Alpha amylase reactivity was evident, but group differences were not significant. Findings indicate dysregulated sympathetic reactivity in Type D individuals, exemplified by a maladaptive haemodynamic profile.

Sexual health experiences, knowledge and understanding in low SES female teenagers: A diary approach

INTRODUCTION

Understanding how teenagers think about sexual health and assessing the ways in which they engage with sexual health information are important issues in the development of appropriate sexual health education programmes. Sexual health education programs in the UK are inconsistent and is not possible to assume that teenagers' information needs are being met by such programs. Teenagers often feel uncomfortable discussing sexual health making it difficult to assess teenagers' understanding and engagement with the topic.

METHODS

we used qualitative diaries to explore how thoughts about and exposure to sexual health information features in teenagers' day-to-day lives. Thirty-three low SES female teenagers aged 13 and 14 from schools in the UK kept a daily note of any sexual health related thoughts and feelings, and any sexual health information they encountered.

RESULTS & CONCLUSIONS

Thematic analysis indicated three themes (1) Knowledge gaps and a desire for factual information (2) The social and emotional context of sexual health and (3) limited access to reliable information. Teenagers showed poor understanding of the biological aspects of sexual health and were concerned about the social and emotional context of sexual health. The teenagers' did not actively seek out sexual health information and access to information resources was limited. Although teenagers showed gaps in their knowledge they were curious about sexual health and were open to receiving sexual health information. Being aware of the ways that low SES female teenagers are thinking about sexual health is useful in developing education programs and other resources that will help fill gaps in knowledge and understanding.

Natural killer cell expression of Ki67 is associated with elevated serum IL-15, disease activity and nephritis in systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a complex autoimmune disorder whose pathology involves multiple immune cell types, including B and T lymphocytes as well as myeloid cells. While it is clear that autoantibody-producing B cells, as well as CD4⁺ T cell help, are key contributors to disease, little is known regarding the role of innate lymphoid cells such as natural killer (NK) cells in the pathogenesis of SLE. We have characterized the phenotype of NK cells by multi-color flow cytometry in a large cohort of SLE patients. While the overall percentage of NK cells was similar or slightly decreased compared to healthy controls, a subset of patients displayed a high frequency of NK cells expressing the proliferation marker, Ki67, which was not found in healthy donors. Although expression of Ki67 on NK cells correlated with Ki67 on other immune cell subsets, the frequency of Ki67 on NK cells was considerably higher. Increased frequencies of Ki67⁺ NK cells correlated strongly with clinical severity and active nephritis and was also related to low NK cell numbers, but not overall leukopenia. Proteomic and functional data indicate that the cytokine interleukin-15 promotes the induction of Ki67 on NK cells. These results suggest a role for NK cells in regulating the immune-mediated pathology of SLE as well as reveal a possible target for therapeutic intervention.

The role of donor-derived exosomes in lung allograft rejection

Lung transplant recipients (LTxRs) with acute or chronic rejection release circulating exosomes that mostly originate from donor lung tissue and express mismatched human leucocyte antigens (HLA) and lung-associated self-antigens (SAgs), Collagen-V and K alpha 1 Tubulin. During lung transplant (LTx), donor lungs often undergo injuries that increase the antigenicity of the transplanted organ. 30% of LTxRs also have pre-transplant antibodies (Abs) to HLA and lung SAgs, which may induce conditions that increase the risk of chronic lung allograft dysfunction (CLAD). Post-transplant, some recipients experience de novo development of Abs to mismatched donor HLA (donor-specific antibody [DSA]) and Abs to lung SAgs, which have been implicated in CLAD pathogenesis. Because most LTxRs who develop DSA also develop Abs to SAgs, some have suggested a synergistic relationship between alloimmunity and autoimmunity in CLAD immunopathogenesis. These processes likely occur from stress-induced exosome release. Exosomes carry allo-antigens, lung SAgs, several micro RNAs, proteasome, co-stimulatory molecules, and pro-inflammatory transcription factors-resulting in efficient antigen presentation by direct, semidirect, and indirect pathways, leading to immune responses to both allo-antigens and lung-associated SAgs. This review summarizes recent findings on the role of exosomes, and processes triggering immune responses to allo-antigens and lung SAgs that ultimately culminate in CLAD.

STRmix™ collaborative exercise on DNA mixture interpretation

An intra and inter-laboratory study using the probabilistic genotyping (PG) software STRmix™ is reported. Two complex mixtures from the PROVEDIt set, analysed on an Applied Biosystems™ 3500 Series Genetic Analyzer, were selected. 174 participants responded. For Sample 1 (low template, in the order of 200 rfu for major contributors) five participants described the comparison as inconclusive with respect to the POI or excluded him. Where LRs were assigned, the point estimates ranging from 2 × 10⁴ to 8 × 10⁶. For Sample 2 (in the order of 2000 rfu for major contributors), LRs ranged from 2 × 10²⁸ to 2 × 10²⁹. Where LRs were calculated, the differences between participants can be attributed to (from largest to smallest impact): This study demonstrates a high level of repeatability and reproducibility among the participants. For those results that differed from the mode, the differences in LR were almost always minor or conservative.

Many Labs 2: Investigating Variation in Replicability Across Samples and Settings

We conducted preregistered replications of 28 classic and contemporary published findings, with protocols that were peer reviewed in advance, to examine variation in effect magnitudes across samples and settings. Each protocol was administered to approximately half of 125 samples that comprised 15,305 participants from 36 countries and territories. Using the conventional criterion of statistical significance ( p < .05), we found that 15 (54%) of the replications provided evidence of a statistically significant effect in the same direction as the original finding. With a strict significance criterion ( p < .0001), 14 (50%) of the replications still provided such evidence, a reflection of the extremely high-powered design. Seven (25%) of the replications yielded effect sizes larger than the original ones, and 21 (75%) yielded effect sizes smaller than the original ones. The median comparable Cohen’s ds were 0.60 for the original findings and 0.15 for the replications. The effect sizes were small (< 0.20) in 16 of the replications (57%), and 9 effects (32%) were in the direction opposite the direction of the original effect. Across settings, the Q statistic indicated significant heterogeneity in 11 (39%) of the replication effects, and most of those were among the findings with the largest overall effect sizes; only 1 effect that was near zero in the aggregate showed significant heterogeneity according to this measure. Only 1 effect had a tau value greater than .20, an indication of moderate heterogeneity. Eight others had tau values near or slightly above .10, an indication of slight heterogeneity. Moderation tests indicated that very little heterogeneity was attributable to the order in which the tasks were performed or whether the tasks were administered in lab versus online. Exploratory comparisons revealed little heterogeneity between Western, educated, industrialized, rich, and democratic (WEIRD) cultures and less WEIRD cultures (i.e., cultures with relatively high and low WEIRDness scores, respectively). Cumulatively, variability in the observed effect sizes was attributable more to the effect being studied than to the sample or setting in which it was studied.

Prevalence and Natural History of Barrett's Esophagus in Lung Transplant: A Single-Center Experience

BACKGROUND

Barrett's esophagus (BE)-intestinal metaplasia in the esophagus-may progress to low-grade dysplasia (LGD), high-grade dysplasia (HGD), and ultimately, invasive esophageal adenocarcinoma (EAC). The course of BE in immunosuppressed lung transplant recipients is unknown.

METHODS

This study retrospectively reviewed the records of patients who underwent lung transplant at a single center, Norton Thoracic Institute in Phoenix, Arizona, between January 1, 2010 and October 31, 2016. Pretransplant esophagram, esophagogastroduodenoscopy, 24-hour pH monitoring, high-resolution manometry, and gastric emptying studies were analyzed.

RESULTS

Of the 466 patients who underwent lung transplant during the study period, 54 (11.59%) had BE on pretransplant esophagogastroduodenoscopy. Of these, 1 patient had HGD before lung transplant. The median age of patients was 64 years (interquartile range, 58.25 to 68.75 years); 66.7% were men. Median follow-up duration was 29.48 months (interquartile range, 19.69 to 37.98 months). Sixteen of 54 patients (29.62%) underwent antireflux surgery after lung transplant. LGD or EAC developed in 3 patients during posttransplant surveillance. One patient had a diagnosis of HGD 24 months after retransplant. She underwent complete endoscopic ablation and was dysplasia-free for 5 months, but ultimately the condition recurred, and she underwent esophagectomy for invasive cancer. Two patients had a diagnosis of LGD 7 and 13 months after lung transplant and were successfully treated with radiofrequency ablation. The rate of progression to dysplasia or EAC was 2.3% per patient-year.

CONCLUSIONS

BE seems to be more prevalent in lung transplant recipients than in the general population. The study findings suggest that patients with BE have a higher risk of BE-to-EAC progression after lung transplant and that HGD may progress rapidly in immunosuppressed patients. More intensive surveillance endoscopy may be required in patients with BE after lung transplant.

Type I interferon receptor blockade with anifrolumab corrects innate and adaptive immune perturbations of SLE

Objective

Anifrolumab is a fully human immunoglobulin G₁ κ monoclonal antibody specific for subunit 1 of the type I interferon (IFN) α receptor. In a phase IIb study of adults with moderate to severe SLE, anifrolumab treatment demonstrated substantial reductions in multiple clinical endpoints. Here, we evaluated serum proteins and immune cells associated with SLE pathogenesis, type I interferon gene signature (IFNGS) test status and disease activity, and how anifrolumab affected these components.

Methods

Whole blood samples were collected from patients enrolled in MUSE (NCT01438489) for serum protein and cellular assessments at baseline and subsequent time points. Data were parsed by IFNGS test status (high/low) and disease activity. Protein expression and immune cell subsets were measured using multiplex immunoassay and flow cytometry, respectively. Blood samples from healthy donors were analysed for comparison.

Results

Baseline protein expression differed between patients with SLE and healthy donors, IFNGS test-high and -low patients, and patients with moderate and severe disease. Anifrolumab treatment lowered concentrations of IFN-induced chemokines associated with B, T and other immune cell migration in addition to proteins associated with endothelial activation that were dysregulated at baseline. IFNGS test-high patients and those with high disease activity were characterised by low baseline numbers of lymphocytes, circulating memory T-cell subsets and neutrophils. Anifrolumab treatment reversed lymphopenia and neutropenia in the total population, and normalised multiple T-cell subset counts in IFNGS test-high patients compared with placebo.

Conclusions

Anifrolumab treatment reversed IFN-associated changes at the protein and cellular level, indicating multiple modes of activity.

Trial registration number

NCT01438489.

Overcoming the dichotomy of implementing societal flood risk management while conserving instream fish habitat - A long-term study from a highly modified urban river

Flood Risk Management (FRM) is often essential to reduce the risk of flooding to properties and infrastructure in urban landscapes, but typically degrades the habitats required by many aquatic animals for foraging, refuge and reproduction. This conflict between flood risk management and biodiversity is driven by conflicting directives, such as the EU Floods and Water Framework Directives, and has led to a requirement for synergistic solutions for FRM that integrate river restoration actions. Unfortunately, ecological monitoring and appraisal of combined FRM and river restoration works is inadequate. This paper uses a case study from the River Don in Northern England to evaluate the effects of the FRM and subsequent river restoration works on instream habitat and the associated fish assemblage over an 8-year period. Flood risk management created a homogeneous channel but did not negatively affect fish species composition or densities, specifically brown trout. Densities of adult brown trout were comparable pre and post-FRM, while densities of juvenile bullhead and brown trout increased dramatically post FRM. River restoration works created a heterogeneous channel but did not significantly improve species composition or brown trout density. Species composition post-river restoration works returned to that similar to pre-FRM over a short-term period, but with improved numbers of juvenile bullhead. Although habitat complexity increased after river restoration works, long-term changes in species composition and densities were marginal, probably because the river reset habitat complexity within the time framework of the study.

Glucose regulation and face recognition deficits in older adults: the role of attention

The present study investigated the perceptual, attentional, and memory processes underlying face recognition deficits observed in older adults with impaired glucoregulation. Participants were categorized as good glucoregulators or poor glucoregulators on the basis of an oral glucose tolerance test. Using event-related potential (ERP) methodology, 23 participants (62-88 years) performed a 2-stimulus oddball task. Participants were asked to rate and memorize 10 "target" faces, which were then presented amongst 120 unfamiliar foils. Behavioral results indicated that good glucoregulators were significantly more accurate at recognizing target faces. ERP markers of early visual perception (P1 and N170 components) and memory formation (P3 component) were unaffected by glucoregulatory efficiency. The P2 component, an index of attentional processing, was larger and delayed in the poor glucoregulators. To the best of our knowledge, this study is the first to suggest that face recognition deficits in poor glucoregulators may be due to impairments in attentional processing.

Tissue-associated self-antigens containing exosomes: Role in allograft rejection

Exosomes are extracellular vesicles that express self-antigens (SAgs) and donor human leukocyte antigens. Tissue-specific exosomes can be detected in the circulation following lung, heart, kidney and islet cell transplantations. We collected serum samples from patients who had undergone lung (n = 30), heart (n = 8), or kidney (n = 15) transplantations to isolate circulating exosomes. Exosome purity was analyzed by Western blot, using CD9 exosome-specific markers. Tissue-associated lung SAgs, collagen V (Col-V) and K-alpha 1 tubulin (Kα1T), heart SAgs, myosin and vimentin, and kidney SAgs, fibronectin and collagen IV (Col-IV), were identified using western blot. Lung transplant recipients diagnosed with bronchiolitis obliterans syndrome had exosomes with higher expression of Col-V (4.2-fold) and Kα1T (37.1-fold) than stable. Exosomes isolated from heart transplant recipients diagnosed with coronary artery vasculopathy had a 3.9-fold increase in myosin and a 4.7-fold increase in vimentin compared with stable. Further, Kidney transplant recipients diagnosed with transplant glomerulopathy had circulating exosomes with a 2-fold increased expression of fibronectin and 2.5-fold increase in Col-IV compared with stable. We conclude that circulating exosomes with tissue associated SAgs have the potential to be a noninvasive biomarker for allograft rejection.

Differences in Adverse Effect Profiles of Corticosteroids in Palliative Care Patients

Background:

Corticosteroids are frequently utilized in the palliative care setting to combat symptoms such as fatigue, dyspnea, pain, weakness, anorexia, cachexia, nausea, and vomiting. Often times, adverse effects arise with corticosteroid use, and it is unclear whether switching to another corticosteroid would reduce the risk of specific adverse effects or what measures can be taken to alleviate the adverse effects.

Objective:

This article aims to review the differentiating pharmacokinetics, potency, and adverse effect profiles of corticosteroids and summarize their clinical applicability.

Methods:

A literature review of “corticosteroids” and “palliative care” was performed using the PubMed database through July 2018. Original studies relevant to the purpose of this study were identified and those that met inclusion criteria were included.

Results:

Although corticosteroids share many common factors, including similar pharmacokinetic, pharmacodymanic, and adverse effect profiles, they have significant differences when the details of these variables are reviewed. Providers that prescribe corticosteroids for symptom management should be aware of these differences and the recommended management strategies.

Conclusions:

Recognition of corticosteroid induced adverse effect profiles and possible management strategies is crucial to optimal symptom management in palliative care patients.

Nodes of Ranvier in Glaucoma

Retinal ganglion cell axons of the DBA/2J mouse model of glaucoma, a model characterized by extensive neuroinflammation, preserve synaptic contacts with their subcortical targets for a time after onset of anterograde axonal transport deficits, axon terminal hypertrophy, and cytoskeletal alterations. Though retrograde axonal transport is still evident in these axons, it is unknown if they retain their ability to transmit visual information to the brain. Using a combination of in vivo multiunit electrophysiology, neuronal tract tracing, multichannel immunofluorescence, and transmission electron microscopy, we report that eye-brain signaling deficits precede transport loss and axonal degeneration in the DBA/2J retinal projection. These deficits are accompanied by node of Ranvier pathology - consisting of increased node length and redistribution of the voltage-gated sodium channel Na_v1.6 that parallel changes seen early in multiple sclerosis (MS) axonopathy. Further, with age, axon caliber and neurofilament density increase without corresponding changes in myelin thickness. In contrast to these findings in DBA/2J mice, node pathologies were not observed in the induced microbead occlusion model of glaucoma - a model that lacks pre-existing inflammation. After one week of systemic treatment with fingolimod, an immunosuppressant therapy for relapsing-remitting MS, DBA/2J mice showed a substantial reduction in node pathology and mild effects on axon morphology. These data suggest that neurophysiological deficits in the DBA/2J may be due to defects in intact axons and targeting node pathology may be a promising intervention for some types of glaucoma.

Using the Plan-Do-Study-Act (PDSA) Model for Continuous Quality Improvement of an Established Simulated Patient Program

Objective

To describe the use of a continuous quality improvement process for strengthening our simulated patient (SP) program and the initial steps that have been implemented.

Innovation

A workgroup that included five clinical faculty with significant experience working with SPs and a strong interest in improving the SP program was developed. The Plan-Do-Study-Act model was used as it allowed for incremental quality improvement changes, in order to ensure a high-quality SP program designed to optimize student learning. Data were gathered from students, SPs, and faculty. Opportunities for improvement were prioritized based on anticipated benefits and available resources. Changes related to planning, implementation, and evaluation and feedback have been executed.

Critical Analysis

Changes related to planning that were implemented included developing handbooks for SPs, faculty, and graduate student instructors, as well as material for students in order to better describe the program. SPs are now referred to as "simulated" as opposed to "standardized" as part of a broader effort to clarify the purpose of SP interactions to students. Streamlined rubrics have been piloted, including electronic rubrics for first year students. SPs are being trained on fewer cases, in order to improve the training program. When possible, activities now take place in one large classroom instead of many small classrooms to improve oversight. Finally, additional feedback has been obtained from SPs via a retreat. These changes have been well received by students, SPs, and faculty.

Next Steps

The collection of this data and initial quality improvement changes provided a basis for hiring a full-time employee who will: dedicate 50% of their time to programmatic assessment of the SP program, support faculty with logistics and training, and be the face of our program to the students and SPs. Further, formal quantitative and qualitative assessment of the SP program has begun.

Using the LACE Score as a Predictor of Clinical Outcomes in Patients Referred for Inpatient Palliative Care Consultation: A Single-Center Experience

BACKGROUND

Readmissions and death for palliative care patients are common and costly outcomes for hospitals, patients, and/or caregivers. Predicting which patients are likely to be readmitted or die within 30 days would help allocate resources and aid in patient disposition planning. Few factors have been strongly correlated with predicting which patients will be readmitted or die within 30 days of hospital discharge. The LACE (Length of Stay, Acuity of admission, Charlson comorbidity index, Emergency department use) score has been validated in medical/surgical patients; however, it has not been evaluated in the palliative care population.

OBJECTIVE

To evaluate the LACE score in palliative care population.

DESIGN

This study was a single-center retrospective cohort design.

SETTING/PATIENTS

Patients were identified based on their consultation to an inpatient palliative care service.

MEASUREMENTS

Thirty-day readmissions, 30-day mortality, length of stay, acuity of admission, Charlson comorbidity index, emergency department utilization, and demographic information.

RESULTS

The LACE score was not an accurate predictor of clinical outcomes in the palliative care population. Patients who were readmitted or died within 30 days tended to be younger. Patients who were readmitted within 30 days tended to have increased emergency department use in the previous 6 months.

CONCLUSIONS

Our study demonstrates the LACE score may not be a sensitive predictor of clinical outcomes in our institution's palliative care patients. This may be due to the complexity of the required care in this population; thus, other factors should be investigated to determine accurate predictors of patient outcomes to better allocate resources.

A Descriptive Study of Decision-Making Conversations during Pediatric Intensive Care Unit Family Conferences

BACKGROUND

Little is known about how decision-making conversations occur during pediatric intensive care unit (PICU) family conferences (FCs).

OBJECTIVE

Describe the decision-making process and implementation of shared decision making (SDM) during PICU FCs.

DESIGN

Observational study.

SETTING/SUBJECTS

University-based tertiary care PICU, including 31 parents and 94 PICU healthcare professionals involved in FCs.

MEASUREMENTS

We recorded, transcribed, and analyzed 14 PICU FCs involving decision-making discussions. We used a modified grounded theory and content analysis approach to explore the use of traditionally described stages of decision making (DM) (information exchange, deliberation, and determining a plan). We also identified the presence or absence of predefined SDM elements.

RESULTS

DM involved the following modified stages: information exchange; information-oriented deliberation; plan-oriented deliberation; and determining a plan. Conversations progressed through stages in a nonlinear manner. For the main decision discussed, all conferences included a presentation of the clinical issues, treatment alternatives, and uncertainty. A minority of FCs included assessing the family's understanding (21%), assessing the family's need for input from others (28%), exploring the family's desired decision-making role (35%), and eliciting the family's opinion (42%).

CONCLUSIONS

In the FCs studied, we found that DM is a nonlinear process. We also found that several SDM elements that could provide information about parents' perspectives and needs did not always occur, identifying areas for process improvement.

The physical and psychological health benefits of positive emotional writing: Investigating the moderating role of Type D (distressed) personality

OBJECTIVES

Type D personality is associated with psychological and physical ill-health. However, there has been limited investigation of the role of Type D personality in interventions designed to enhance well-being. This study investigated associations between Type D personality and the efficacy of positive emotional writing for reducing stress, anxiety, and physical symptoms.

DESIGN

A between-subjects longitudinal design was employed.

METHOD

Participants (N = 71, M_age  = 28.2, SD_age  = 12.4) completed self-report measures of Type D personality, physical symptoms, perceived stress, and trait anxiety, before completing either (1) positive emotional writing or (2) a non-emotive control writing task, for 20 min per day over three consecutive days. State anxiety was measured immediately before and after each writing session, and self-report questionnaires were again administered 4 weeks post-writing.

RESULTS

Participants in the positive emotional writing condition showed significantly greater reductions in (1) state anxiety and (2) both trait anxiety and perceived stress over the 4-week follow-up period, compared to the control group. While these effects were not moderated by Type D personality, a decrease in trait anxiety was particularly evident in participants who reported both high levels of social inhibition and low negative affectivity. Linguistic analysis of the writing diaries showed that Type D personality was positively associated with swear word use, but not any other linguistic categories.

CONCLUSION

These findings support the efficacy of positive emotional writing for alleviating stress and anxiety, but not perceived physical symptoms. Swearing may be a coping strategy employed by high Type D individuals. Statement of contribution What is already known on this subject? Type D (distressed) personality is characterized by high levels of both negative affectivity and social inhibition, and has been associated with adverse physical and psychological health. Positive emotional writing is known to reduce subjectively reported physical symptoms and increase positive affect. What does this study add? Positive emotional writing was shown to attenuate (1) state anxiety immediately post-writing, and (2) trait anxiety and perceived stress 4 weeks post-writing. The findings demonstrate that positive writing might be a useful intervention for attenuating the adverse psychological effects of Type D personality in the general population. Type D personality was associated with more frequent use of swear words, which may be a coping mechanism used by high Type D individuals.

Primary paraesophageal hernia repair with Gore® Bio-A® tissue reinforcement: long-term outcomes and association of BMI and recurrence

BACKGROUND

Laparoscopic repair remains the gold-standard treatment for paraesophageal hernia (PEH). We analyzed long-term symptomatic outcomes and surgical reintervention rates after primary PEH repair with onlay synthetic bioabsorbable mesh (W. L. Gore & Associates, Inc., Flagstaff, AZ) and examined body mass index (BMI) as a possible risk factor for poor outcomes and for recurrence.

METHODS

We queried a prospectively maintained database to identify patients who underwent laparoscopic primary PEH repair with onlay patch of a bioprosthetic absorbable mesh (Bio-A® Gore®) between 05/28/2009 and 12/31/2013. Electronic health records were accessed to record demographic and operative data and were reviewed up to the present to identify any repeat procedures. Patients were grouped according to preoperative BMI (A: BMI < 25; B: BMI = 25-29.9; C: BMI = 30-34.9; D: BMI ≥ 35). Patients completed standardized satisfaction and symptom surveys.

RESULTS

In total, 399 patients were included. Most patients (n = 261; 65.4%) were women. Mean age was 59.6 ± 13.4 years; mean BMI was 29.9 ± 5.0 kg/m². The patients were grouped as follows: A, 53 patients (13.3%); B, 166 (41.6%); C, 115 (28.8%); D: 65 (16.3%). Four procedures (1.0%) were converted from laparoscopy to open procedures. All patients underwent an antireflux procedure (225 Nissen, 170 Toupet, 4 Dor). A mean follow-up of 44.7 ± 22.8 months was available for 305 patients (76.4%). 24/305 patients (7.9%) underwent reoperation, and the number of reoperations did not differ among groups (P = 0.64). Long-term symptomatic outcomes were available for 217/305 patients (71.1%) at a mean follow-up of 54.0 ± 13.1  months; no significant difference was observed among groups. 194/217 patients (89.4%) reported good to excellent satisfaction, with no significant differences among the groups.

CONCLUSIONS

Laparoscopic primary PEH repair with onlay Bio-A® mesh is a safe and feasible procedure with excellent long-term patient-centered outcomes and acceptable symptomatic recurrence rate. BMI does not appear to be related to the need for surgical reintervention.

The relationship between Type D personality and physical health complaints is mediated by perceived stress and anxiety but not diurnal cortisol secretion

Type D personality has been associated with minor health complaints in the general population and dysregulation of basal cortisol secretion in coronary patients. The aims of the present study were to investigate (i) whether there is an association between Type D personality and basal cortisol secretion in the general population, and (ii) whether subjective measures of stress and anxiety, as well as indices of basal cortisol secretion, mediate the relationship between Type D personality and self-reported physical symptoms in this group. Self-report measures of stress, trait anxiety and physical symptoms were provided by 101 individuals aged 18-45 years. Saliva samples were also provided over two consecutive "typical" days, to enable indices of the cortisol awakening response and diurnal cortisol profile to be determined. There was a significant relationship between Type D personality and self-reported physical symptoms, which was fully mediated by subjective stress and anxiety. However, there were no significant relationships between Type D personality and the basal cortisol indices. These findings suggest that the association between Type D personality and minor health complaints in the general population can be explained by feelings of stress and anxiety, but a precise biological mechanism for this link is yet to be elucidated.

Zbtb7a induction in alveolar macrophages is implicated in anti-HLA-mediated lung allograft rejection

Chronic rejection significantly limits long-term success of solid organ transplantation. De novo donor-specific antibodies (DSAs) to mismatched donor human leukocyte antigen after human lung transplantation predispose lung grafts to chronic rejection. We sought to delineate mediators and mechanisms of DSA pathogenesis and to define early inflammatory events that trigger chronic rejection in lung transplant recipients and obliterative airway disease, a correlate of human chronic rejection, in mouse. Induction of transcription factor zinc finger and BTB domain containing protein 7a (Zbtb7a) was an early response critical in the DSA-induced chronic rejection. A cohort of human lung transplant recipients who developed DSA and chronic rejection demonstrated greater Zbtb7a expression long before clinical diagnosis of chronic rejection compared to nonrejecting lung transplant recipients with stable pulmonary function. Expression of DSA-induced Zbtb7a was restricted to alveolar macrophages (AMs), and selective disruption of Zbtb7a in AMs resulted in less bronchiolar occlusion, low immune responses to lung-restricted self-antigens, and high protection from chronic rejection in mice. Additionally, in an allogeneic cell transfer protocol, antigen presentation by AMs was Zbtb7a-dependent where AMs deficient in Zbtb7a failed to induce antibody and T cell responses. Collectively, we demonstrate that AMs play an essential role in antibody-induced pathogenesis of chronic rejection by regulating early inflammation and lung-restricted humoral and cellular autoimmunity.

Avirulent Bacillus anthracis Strain with Molecular Assay Targets as Surrogate for Irradiation-Inactivated Virulent Spores

The revelation in May 2015 of the shipment of γ irradiation–inactivated wild-type Bacillus anthracis spore preparations containing a small number of live spores raised concern about the safety and security of these materials. The finding also raised doubts about the validity of the protocols and procedures used to prepare them. Such inactivated reference materials were used as positive controls in assays to detect suspected B. anthracis in samples because live agent cannot be shipped for use in field settings, in improvement of currently deployed detection methods or development of new methods, or for quality assurance and training activities. Hence, risk-mitigated B. anthracis strains are needed to fulfill these requirements. We constructed a genetically inactivated or attenuated strain containing relevant molecular assay targets and tested to compare assay performance using this strain to the historical data obtained using irradiation-inactivated virulent spores.

Autologous Blood Transfusion in Elective Orthopaedic Surgery

Autologous blood transfusion is one of the most effective ways of avoiding the need for homologous transfusion and all its associated complications. Since the beginning of 1985, autotransfusions have been used in 48 patients undergoing total joint replacement, without significant complications. Their average haemoglobin level two weeks postoperatively was 11.3 mg/dl. We believe that this is a safe, effective and economical procedure which benefits both patients and medical staff, and its use should be more widespread.

Symptom burden in heart failure: assessment, impact on outcomes, and management

Evidence-based management has improved long-term survival in patients with heart failure (HF). However, an unintended consequence of increased longevity is that patients with HF are exposed to a greater symptom burden over time. In addition to classic symptoms such as dyspnea and edema, patients with HF frequently suffer additional symptoms such as pain, depression, gastrointestinal distress, and fatigue. In addition to obvious effects on quality of life, untreated symptoms increase clinical events including emergency department visits, hospitalizations, and long-term mortality in a dose-dependent fashion. Symptom management in patients with HF consists of two key components: comprehensive symptom assessment and sufficient knowledge of available approaches to alleviate the symptoms. Successful treatment addresses not just the physical but also the emotional, social, and spiritual aspects of suffering. Despite a lack of formal experience during cardiovascular training, symptom management in HF can be learned and implemented effectively by cardiology providers. Co-management with palliative medicine specialists can add significant value across the spectrum and throughout the course of HF.

Provider Perspectives on Topical Analgesics

Topical analgesics are effective and alternative means to systemic therapy, often minimizing the adverse drug effects and complications of systemic analgesic use. Despite the number of available topical analgesics, there is little direction provided in practice guidelines on their appropriate use and little is known about patterns of their prescribing. To begin understanding these knowledge gaps, we sought provider perspectives on topical analgesic use at a large academic medical center. This electronic survey seeks to explore the perceptions and prescription patterns of topical analgesics among prescribers in a large academic medical center, where the availability of topical analgesics varies. Among topical analgesics, lidocaine (78%) is prescribed more frequently than nonsteroidal anti-inflammatory drugs (NSAIDs; 41%) or morphine (3%). Formulations and indications of use varied between faculty physicians and nonfaculty providers. Reasons for prescribing were largely based on anecdotal experience. Based on the survey results, it is clear that more topical agents are needed to manage pain; however, so too is guidance on appropriate prescribing.

Circulating Exosomes with Distinct Properties during Chronic Lung Allograft Rejection

Circulating exosomes containing donor HLA and lung-associated self-antigens (SAg) are thought to play an important role in allograft rejection after human lung transplantation. We characterized exosomes isolated from serum of 10 lung transplant recipients (LTxR) diagnosed with bronchiolitis obliterans syndrome (BOS) and compared them with exosomes isolated from serum of 10 stable LTxR. Lung-associated SAg (K-α-1-tubulin [Kα1T] and collagen V [Col-V]), MHC class II molecules, costimulatory molecules CD40, CD80, and CD86, and transcription factors class II MHC trans-activator, NF-κB, hypoxia-inducible factor 1-α, IL-1R-associated kinase 1, MyD88, and 20S proteasome were detected in exosomes from BOS, but not stable LTxR. In contrast, adhesion molecules were present in both groups. C57BL/6 mice immunized with exosomes from BOS but not stable LTxR demonstrated Ab to SAg (Col-V, 33.5 ± 15.7 versus 10.4 ± 6.4, p = 0.021; Kα1T, 925 ± 403 versus 317 ± 285, p = 0.044) and HLA (mean fluorescence intensity: BOS, 8450; stable, 632; p < 0.05). Furthermore, splenic lymphocytes demonstrated increased frequency of lung SAg-specific IL-17 (Col-V, 128 ± 46 versus 31 ± 21, p = 0.013; Kα1T, 194 ± 47 versus 67 ± 43, p = 0.014) and IFN-γ (Col-V, 165 ± 79 versus 38 ± 40, p = 0.042; Kα1T, 232 ± 64 versus 118 ± 39, p = 0.012). Reduced levels of IL-10-producing cells were seen in BOS exosome immunized mice compared with mice immunized with stable exosomes (Col-V, 59 ± 23 versus 211 ± 85, p = 0.016; Kα1T, 78 ± 49 versus 295 ± 104, p = 0.017). Owing to the unique immune-stimulating properties of exosomes induced during rejection, we propose that they play an important role in eliciting both alloantigen- and SAg-specific immunity, leading to chronic rejection after lung transplantation.

LKB1 inactivation occurs in a subset of esophageal adenocarcinomas and is sufficient to drive tumor cell proliferation

BACKGROUND

The incidence of esophageal adenocarcinoma (EAC) has increased over the last several decades. Apart from mutations in TP53 gene, there are little data on genetic drivers of EAC. Liver kinase B1 (LKB1) has emerged as a multifunctional tumor suppressor regulating cell growth, differentiation, and metabolism. Somatic inactivation of LKB1 has been described in several tumor types; however, whether LKB1 inactivation has a role in EAC is unknown. Here we analyzed patient tumors to assess the prevalence of LKB1 loss in EAC.

METHODS

Chromosomal deletion and expression of LKB1 in EAC were investigated using publicly available genomic data. Protein expression was assessed by immunohistochemistry (IHC) analysis for LKB1 in a tissue microarray (TMA) containing esophageal tumor specimens, including EAC. LKB1 was suppressed in EAC cells to determine the effects on cell growth in vitro.

RESULTS

Analysis of EAC data in The Cancer Genome Atlas dataset revealed significant deletion of chromosome 19p13.3, containing the LKB1 gene locus. Single copy loss (shallow deletion) of LKB1 was present in 58% of EAC samples. Expression of LKB1 was significantly lower in EAC tumors compared with normal esophagus. IHC analysis showed reduced LKB1 protein expression in EAC. Suppression of LKB1 was sufficient to enhance EAC cell growth in vitro.

CONCLUSIONS

Our data suggest that inactivation of LKB1 frequently occurs in EAC. Based on the reported oncogenic effects of LKB1 inactivation, our data indicate that LKB1 loss may play a significant role in EAC tumorigenesis, and point to the need for future studies.

Doctor-patient relationship and quality of life in Irritable Bowel Syndrome: an exploratory study of the potential mediating role of illness perceptions and acceptance

Irritable Bowel Syndrome (IBS) is a functional gastrointestinal disorder characterised by unpredictable bowel symptoms. These can be difficult to manage, consequently impacting quality of life (QoL). In addition, a strained doctor-patient relationship is independently reported in the qualitative literature. Given the doctor is often the first port of call for people with IBS, a difficult relationship may influence subsequent IBS management. Research suggests illness perceptions are important in determining IBS outcomes in therapy; however, their association with doctor-patient relationship and QoL is yet to be investigated. This exploratory study aimed to investigate the association between these constructs in IBS, as well as potential mediation by illness perceptions. Online questionnaires measuring doctor-patient relationship, illness perceptions, acceptance and QoL, were completed by 167 participants who reported an IBS diagnosis (144 female, mean age = 44.22 years, SD = 15.91 years). Bootstrapped pathway analysis was used to model the relationship and mediation effects. There was a significant positive correlation between patient-doctor relationship and QoL, r = .258, n = 167, p = .001. There was a significant indirect effect between doctor-patient relationship and QoL through illness coherence and acceptance (bootstrapped estimate = .058, 95%CI Lower-Upper = .02, .095, p = .002). No other indirect effects were observed in combination with good fit indices for the other illness perceptions. Findings suggest a doctor-patient relationship which fosters mutual understanding and helps patients make sense of symptoms, increases their ability to manage their IBS in a psychologically flexible manner, subsequently helping them maintain their QoL.

Enhanced Phosphorylation of Bax and Its Translocation into Mitochondria in the Brains of Individuals Affiliated with Alzheimer's Disease

Background:

Despite increased neuronal death, senile plaques, and neurofibrillary tangles observed in patients suffering from Alzheimer’s disease (AD), the detailed mechanism of cell death in AD is still poorly understood.

Method:

We hypothesized that p38 kinase activates and then phosphorylates Bax, leading to its translocation to mitochondria in AD brains compared to controls. The aim of this study was to investigate the role of p38 kinase in phosphorylation and sub-cellular localization of pro-apoptotic Bax in the frontal cortex of the brains from AD and control subjects. Increased oxidative stress in AD individuals compared to control was evaluated by measuring the levels of carbonylated proteins and oxidized peroxiredoxin, an antioxidant enzyme. The relative amounts of p38 kinase and phospho-Bax in mitochondria in AD brains and controls were determined by immunoblot analysis using the respective antibody against each protein following immunoprecipitation.

Results:

Our results showed that the levels of oxidized peroxiredoxin-SO₃ and carbonylated proteins are significantly elevated in AD brains compared to controls, demonstrating the increased oxidative stress.

Conclusion:

The amount of phospho-p38 kinase is increased in AD brains and the activated p38 kinase appears to phosphorylate Thr residue(s) of Bax, which leads to its mitochondrial translocation, contributing to apoptosis and ultimately, neurodegeneration.

Utilization of a virtual patient for advanced assessment of student performance in pain management

BACKGROUND AND PURPOSE

To assess student performance and achievement of course objectives following the integration of a virtual patient case designed to promote active, patient-centered learning in a required pharmacy course.

EDUCATIONAL ACTIVITY AND SETTING

DecisionSim™ (Kynectiv, Inc., Chadsford, PA), a dynamic virtual patient platform, was used to implement an interactive patient case to augment pain management material presented during a didactic session in a pharmacotherapy course. Simulation performance data were collected and analyzed. Student exam performance on pain management questions was compared to student exam performance on nearly identical questions from a prior year when a paper-based case was used instead of virtual patient technology.

FINDINGS

Students who performed well on the virtual patient case performed better on exam questions related to patient assessment (p = 0.0244), primary pharmacological therapy (p = 0.0001), and additional pharmacological therapy (p = 0.0001). Overall exam performance did not differ between the two groups. However, students with exposure to the virtual patient case demonstrated significantly better performance on higher level Bloom's Taxonomy questions that required them to create pharmacotherapy regimens (p=0.0005). Students in the previous year (exposed only to a paper patient case) performed better in calculating conversions of opioids for patients (p = 0.0001).

SUMMARY

Virtual patient technology may enhance student performance on high-level Bloom's Taxonomy examination questions. This study adds to the current literature demonstrating the value of virtual patient technology as an active-learning strategy.

Extracorporeal membrane oxygenation as a bridge to lung transplantation: A single-center experience in the present era

OBJECTIVE

Extracorporeal membrane oxygenation has been used as a bridge to lung transplantation in patients with rapid pulmonary function deterioration. The reported success of this modality and perioperative and functional outcomes are varied.

METHODS

We retrospectively reviewed all patients who underwent lung transplantation at our institution over 1 year (January 1, 2015, to December 31, 2015). Patients were divided into 2 groups depending on whether they required extracorporeal membrane oxygenation support as a bridge to transplant; preoperative characteristics, lung transplantation outcomes, and survival were compared between groups.

RESULTS

Of the 93 patients, 12 (13%) received bridge to transplant, and 81 (87%) did not. Patients receiving bridge to transplant were younger, had higher lung allocation scores, had lower functional status, and were more often on mechanical ventilation at listing. Most patients who received bridge to transplant (n = 10, 83.3%) had pulmonary fibrosis. Mean pretransplant extracorporeal membrane oxygenation support was 103.6 hours in duration (range, 16-395 hours). All patients who received bridge to transplant were decannulated immediately after lung transplantation but were more likely to return to the operating room for secondary chest closure or rethoracotomy. Grade 3 primary graft dysfunction within 72 hours was similar between groups. Lung transplantation success and hospital discharge were 100% in the bridge to transplant group; however, these patients experienced longer hospital stays and higher rates of discharge to acute rehabilitation. The 1-year survival was 100% in the bridge to transplant group and 91% in the non-bridge to transplant group (log-rank, P = .24). The 1-year functional status was excellent in both groups.

CONCLUSIONS

Extracorporeal membrane oxygenation can be used to safely bridge high-acuity patients with end-stage lung disease to lung transplantation with good 30-day, 90-day, and 1-year survival and excellent 1-year functional status. Long-term outcomes are being studied.

Seeking sexual health information? Professionals' novel experiences of the barriers that prevent female adolescents seeking sexual health information

Objective Sexual health professionals are key stakeholders in implementing sexual health intervention programmes, yet their views are largely absent from the literature. Sexual health professionals provide a unique perspective on teen sexual health issues as they engage in confidential discussions with a wide range of teenagers. This study aimed to provide an in-depth exploration of professionals' perceptions of teenagers' sexual health information seeking practices and barriers. Furthermore, the research provided a unique re-examination of key predictors of risky sexual behaviours, which have been highlighted by previous research. Methods Nine semi-structured interviews were undertaken with sexual health professionals to explore their perceptions of teenagers' sexual health information seeking practises and barriers. Subsequently the professionals rank ordered the 57 factors identified in previous research in terms of their perceived importance in predicting risky sexual behaviours. Results Four themes emerged: "society and media"; "environment and family"; "peer influences"; and "the self". The rank order task confirmed that 33 of the 57 factors were perceived as highly important by sexual health professionals. Conclusion Society, peers, environment and family are perceived as barriers to teenagers seeking reliable sexual health information, but these are dependent on the individual person. An individual with higher self-esteem is more confident in seeking sexual health information and applying this knowledge appropriately. Self-esteem was also identified as a key perceived predictor of risky sexual behaviours. Therefore, there is scope for intervention programmes targeting self-esteem and knowledge, so teenagers have the confidence to seek out sexual health information and to make their own informed sexual health decisions.

A 46-Year-Old Man With Dyspnea, Hypoxemia, and Radiographic Asymmetry After Redo Bilateral Lung Transplantation

CASE PRESENTATION

A 46-year-old man underwent redo bilateral sequential lung transplantation for rapidly progressive bronchiolitis obliterans syndrome that developed 3.5 years after initial transplantation. In the operating room, he was sedated and intubated with a dual lumen endotracheal tube with subsequent single right-lung ventilation and left allograft implantation. His pulmonary arterial pressure became elevated with reperfusion of the newly implanted left lung, which required initiation of cardiopulmonary bypass to facilitate implantation of the right lung. After implantation and reperfusion of the right lung, the patient was weaned from cardiopulmonary bypass. His chest was closed and he was transferred to the thoracic intensive care unit. On arrival to the intensive care unit, the patient was intubated, sedated, and had an oxygen saturation of 92% on a fraction of inspired oxygen of 100%, positive end-expiratory pressure of 10 cm H₂O, and 20 parts per million of inhaled nitric oxide. He had a Swan-Ganz catheter in the right internal jugular vein that measured a mean pulmonary arterial pressure of 33 mm Hg and a pulmonary arterial systolic pressure of 63 mm Hg, which remained persistently elevated and prompted further diagnostic evaluation.

Psychobiological responses to critically evaluated multitasking

In order to understand psychobiological responses to stress it is necessary to observe how people react to controlled stressors. A range of stressors exist for this purpose; however, laboratory stressors that are representative of real life situations provide more ecologically valid opportunities for assessing stress responding. The current study assessed psychobiological responses to an ecologically valid laboratory stressor involving multitasking and critical evaluation. The stressor elicited significant increases in psychological and cardiovascular stress reactivity; however, no cortisol reactivity was observed. Other socially evaluative laboratory stressors that lead to cortisol reactivity typically require a participant to perform tasks that involve verbal responses, whilst standing in front of evaluative others. The current protocol contained critical evaluation of cognitive performance; however, this was delivered from behind a seated participant. The salience of social evaluation may therefore be related to the response format of the task and the method of evaluation. That is, the current protocol did not involve the additional vulnerability associated with in person, face-to-face contact, and verbal delivery. Critical evaluation of multitasking provides an ecologically valid technique for inducing laboratory stress and provides an alternative tool for assessing psychological and cardiovascular reactivity. Future studies could additionally use this paradigm to investigate those components of social evaluation necessary for eliciting a cortisol response.

The role of fear in predicting sexually transmitted infection screening

OBJECTIVE

This study assessed the extent to which social-cognitive factors (attitude, subjective norm and perceived control) and the fear of a positive test result predict sexually transmitted infection (STI) screening intentions and subsequent behaviour.

DESIGN

Study 1 (N = 85) used a longitudinal design to assess the factors that predict STI screening intention and future screening behaviour measured one month later at Time 2. Study 2 (N = 102) used an experimental design to determine whether the relationship between fear and screening varied depending on whether STI or HIV screening was being assessed both before and after controlling for social-cognitive factors.

MAIN OUTCOME MEASURES

Across the studies the outcome measures were sexual health screening.

RESULTS

In both studies, the fear of having an STI positively predicted STI screening intention. In Study 1, fear, but not the social-cognitive factors, also predicted subsequent STI screening behaviour. In Study 2, the fear of having HIV did not predict HIV screening intention, but attitude negatively and response efficacy positively predicted screening intention.

CONCLUSION

This study highlights the importance of considering the nature of the health condition when assessing the role of fear on health promotion.

Monkey prefrontal neurons during Sternberg task performance: full contents of working memory or most recent item?

To explore the brain mechanisms underlying multi-item working memory, we monitored the activity of neurons in the dorsolateral prefrontal cortex while macaque monkeys performed spatial and chromatic versions of a Sternberg working-memory task. Each trial required holding three sequentially presented samples in working memory so as to identify a subsequent probe matching one of them. The monkeys were able to recall all three samples at levels well above chance, exhibiting modest load and recency effects. Prefrontal neurons signaled the identity of each sample during the delay period immediately following its presentation. However, as each new sample was presented, the representation of antecedent samples became weak and shifted to an anomalous code. A linear classifier operating on the basis of population activity during the final delay period was able to perform at approximately the level of the monkeys on trials requiring recall of the third sample but showed a falloff in performance on trials requiring recall of the first or second sample much steeper than observed in the monkeys. We conclude that delay-period activity in the prefrontal cortex robustly represented only the most recent item. The monkeys apparently based performance of this classic working-memory task on some storage mechanism in addition to the prefrontal delay-period firing rate. Possibilities include delay-period activity in areas outside the prefrontal cortex and changes within the prefrontal cortex not manifest at the level of the firing rate.NEW & NOTEWORTHY It has long been thought that items held in working memory are encoded by delay-period activity in the dorsolateral prefrontal cortex. Here we describe evidence contrary to that view. In monkeys performing a serial multi-item working memory task, dorsolateral prefrontal neurons encode almost exclusively the identity of the sample presented most recently. Information about earlier samples must be encoded outside the prefrontal cortex or represented within the prefrontal cortex in a cryptic code.

Mapping in-vivo optic nerve head strains caused by intraocular and intracranial pressures

Although it is well documented that abnormal levels of either intraocular (IOP) or intracranial pressure (ICP) can lead to potentially blinding conditions, such as glaucoma and papilledema, little is known about how the pressures actually affect the eye. Even less is known about potential interplay between their effects, namely how the level of one pressure might alter the effects of the other. Our goal was to measure in-vivo the pressure-induced stretch and compression of the lamina cribrosa due to acute changes of IOP and ICP. The lamina cribrosa is a structure within the optic nerve head, in the back of the eye. It is important because it is in the lamina cribrosa that the pressure-induced deformations are believed to initiate damage to neural tissues leading to blindness. An eye of a rhesus macaque monkey was imaged in-vivo with optical coherence tomography while IOP and ICP were controlled through cannulas in the anterior chamber and lateral ventricle, respectively. The image volumes were analyzed with a newly developed digital image correlation technique. The effects of both pressures were highly localized, nonlinear and non-monotonic, with strong interactions. Pressure variations from the baseline normal levels caused substantial stretch and compression of the neural tissues in the posterior pole, sometimes exceeding 20%. Chronic exposure to such high levels of biomechanical insult would likely lead to neural tissue damage and loss of vision. Our results demonstrate the power of digital image correlation technique based on non-invasive imaging technologies to help understand how pressures induce biomechanical insults and lead to vision problems.

Correlation between Cerebral Hemodynamic and Perfusion Pressure Changes in Non-Human Primates

The mechanism that maintains a stable blood flow in the brain despite changes in cerebral perfusion pressure (CPP), and therefore guaranties a constant supply of oxygen and nutrients to the neurons, is known as cerebral autoregulation (CA). In a certain range of CPP, blood flow is mediated by a vasomotor adjustment in vascular resistance through dilation of blood vessels. CA is known to be impaired in diseases like traumatic brain injury, Parkinson's disease, stroke, hydrocephalus and others. If CA is impaired, blood flow and pressure changes are coupled and the oxygen supply might be unstable. Lassen's blood flow autoregulation curve describes this mechanism, where a plateau of stable blood flow in a specific range of CPP corresponds to intact autoregulation. Knowing the limits of this plateau and maintaining CPP within these limits can improve patient outcome. Since CPP is influenced by both intracranial pressure and arterial blood pressure, long term changes in either can lead to autoregulation impairment. Non-invasive methods for monitoring blood flow autoregulation are therefore needed. We propose to use Near infrared spectroscopy (NIRS) to fill this need. NIRS is an optical technique, which measures microvascular changes in cerebral hemoglobin concentration. We pe erformed experiments on non-human primates during exsanguination to demonstrate that the limits of blood flow autoregulation can be accessed with NIRS.

Multidimensional Model of Racial Identity: A Reconceptualization of African American Racial Identity

Research on African American racial identity has utilized 2 distinct approaches. The mainstream approach has focused on universal properties associated with ethnic and racial identities. In contrast, the underground approach has focused on documenting the qualitative meaning of being African American, with an emphasis on the unique cultural and historical experiences of African Americans. The Multidimensional Model of Racial Identity (MMRI) represents a synthesis of the strengths of these two approaches. The underlying assumptions associated with the model are explored. The model proposes 4 dimensions of African American racial identity: salience, centrality, regard, and ideology. A description of these dimensions is provided along with a discussion of how they interact to influence behavior at the level of the event. We argue that the MMRI has the potential to make contributions to traditional research objectives of both approaches, as well as to provide the impetus to explore new questions.

Virtual Patient Case Sharing Across Two Schools of Pharmacy

Objective. To expand the use of virtual patients at 2 schools of pharmacy through virtual patient case sharing. Design. Faculty members at two schools of pharmacy collaborated to expand the use of virtual patients. Two simulation programs, vpSim and DecisionSim (Decision Simulation, LLC, Chadsford, PA), were used to create interactive patient cases for a required course and an elective course at the different schools. Each school developed cases for their own use and then shared the cases with the other school. Assessment. The development, sharing, and subsequent modification of cases were examined using a standardized data collection form completed by both schools. Survey instruments were used to gather data regarding faculty perception and student satisfaction. Pre- and post-tests were administered to assess student learning. Five cases were developed and shared between the institutions. The time spent constructing new cases (22 hours/case) was significantly longer than the time spent modifying the shared cases (1.2 hours/case). Faculty members and students were largely satisfied with case sharing and the use of virtual patient cases, respectively. Virtual patients significantly enhanced student learning of material (mean score: 3.2 vs 3.6 on a 5-point scale). Conclusions. The sharing of virtual patient cases may allow institutions to overcome barriers to implementation of virtual patient programs, namely faculty resources, while improving student learning and satisfaction.