POMC: The Physiological Power of Hormone Processing.

Pro-opiomelanocortin (POMC) is the archetypal polypeptide precursor of hormones and neuropeptides. In this review, we examine the variability in the individual peptides produced in different tissues and the impact of the simultaneous presence of their precursors or fragments. We also discuss the problems inherent in accurately measuring which of the precursors and their derived peptides are present in biological samples. We address how not being able to measure all the combinations of precursors and fragments quantitatively has affected our understanding of the pathophysiology associated with POMC processing. To understand how different ratios of peptides arise, we describe the role of the pro-hormone convertases (PCs) and their tissue specificities and consider the cellular processing pathways which enable regulated secretion of different peptides that play crucial roles in integrating a range of vital physiological functions. In the pituitary, correct processing of POMC peptides is essential to maintain the hypothalamic-pituitary-adrenal axis, and this processing can be disrupted in POMC-expressing tumors. In hypothalamic neurons expressing POMC, abnormalities in processing critically impact on the regulation of appetite, energy homeostasis, and body composition. More work is needed to understand whether expression of the POMC gene in a tissue equates to release of bioactive peptides. We suggest that this comprehensive view of POMC processing, with a focus on gaining a better understanding of the combination of peptides produced and their relative bioactivity, is a necessity for all involved in studying this fascinating physiological regulatory phenomenon.

Architecture of the human interactome defines protein communities and disease networks.

The physiology of a cell can be viewed as the product of thousands of proteins acting in concert to shape the cellular response. Coordination is achieved in part through networks of protein-protein interactions that assemble functionally related proteins into complexes, organelles, and signal transduction pathways. Understanding the architecture of the human proteome has the potential to inform cellular, structural, and evolutionary mechanisms and is critical to elucidating how genome variation contributes to disease. Here we present BioPlex 2.0 (Biophysical Interactions of ORFeome-derived complexes), which uses robust affinity purification-mass spectrometry methodology to elucidate protein interaction networks and co-complexes nucleated by more than 25% of protein-coding genes from the human genome, and constitutes, to our knowledge, the largest such network so far. With more than 56,000 candidate interactions, BioPlex 2.0 contains more than 29,000 previously unknown co-associations and provides functional insights into hundreds of poorly characterized proteins while enhancing network-based analyses of domain associations, subcellular localization, and co-complex formation. Unsupervised Markov clustering of interacting proteins identified more than 1,300 protein communities representing diverse cellular activities. Genes essential for cell fitness are enriched within 53 communities representing central cellular functions. Moreover, we identified 442 communities associated with more than 2,000 disease annotations, placing numerous candidate disease genes into a cellular framework. BioPlex 2.0 exceeds previous experimentally derived interaction networks in depth and breadth, and will be a valuable resource for exploring the biology of incompletely characterized proteins and for elucidating larger-scale patterns of proteome organization.

Communicative Practices Clinicians Use to Correct Patient Misconceptions in Primary Care Visits.

To investigate how clinicians correct patient misconceptions, we analyzed 23 video recordings of primary care visits. Analysis focused on operationalizing, identifying, and characterizing clinician corrections, integrating two inductive approaches: microanalysis of clinical interaction and conversation analysis. According to our definition, patient misconception-clinician correction episodes met three essential criteria: (1) the clinician refuted something the patient had said, (2) which the patient had presented without uncertainty, and (3) which contained a proposition that was factually incorrect. We identified 59 such episodes; the patient misconceptions most commonly related to medication issues; fewer than half had foreseeable implications for patients' future actions. We identified seven clinician correction practices: Three direct practices (displaying surprise, marking disagreement, contradicting the patient) and four indirect practices (presenting the correct proposition, providing explanations, invoking an outside authority, demonstrating with evidence). We found an almost equal distribution of these direct and indirect practices.

Visit Linearity in Primary Care Visits for Patients with Chronic Pain on Long-term Opioid Therapy.

BACKGROUND: Physicians and patients report frustration after primary care visits for chronic pain. The need to shift between multiple clinical topics to address competing demands during visits may contribute to this frustration. OBJECTIVE: This study creates a novel measure, "visit linearity," to assess visit organization and examines whether visits that require less shifting back and forth between topics are associated with better patient and physician visit experiences. It also explores whether visit linearity differs depending on the following: (1) whether or not pain is a major topic of the visit and (2) whether or not pain is the first topic raised. DESIGN: This study analyzed 41 video-recorded visits using inductive, qualitative analysis informed by conversation analysis. We used linear regression to evaluate associations between visit organization and post-visit measures of participant experience. PARTICIPANTS: Patients were established adult patients planning to discuss pain management during routine primary care. Physicians were internal or family medicine residents. MAIN MEASURES: Visit linearity, total topics, return topics, topic shifts, time per topic, visit duration, pain main topic, pain first topic, patient experience, and physician difficulty. KEY RESULTS: Visits had a mean of 8.1 total topics (standard deviation (SD)=3.46), 14.5 topic shifts (SD=6.28), and 1.9 topic shifts per topic (SD=0.62). Less linear visits (higher topic shifts to topic ratio) were associated with greater physician visit difficulty (ß=7.28, p<0.001) and worse patient experience (ß= -0.62, p=0.03). Visit linearity was not significantly impacted by pain as a major or first topic raised. CONCLUSIONS: In primary care visits for patients with chronic pain taking opioids, more linear visits were associated with better physician and patient experience. Frequent topic shifts may be disruptive. If confirmed in future research, this finding implies that reducing shifts between topics could help decrease mutual frustration related to discussions about pain.

Intravitreal administration of recombinant human opticin protects against hyperoxia-induced pre-retinal neovascularization.

Opticin is an extracellular glycoprotein present in the vitreous. Its antiangiogenic properties offer the potential for therapeutic intervention in conditions such as proliferative diabetic retinopathy and retinopathy of prematurity. Here, we investigated the hypothesis that intravitreal administration of recombinant human opticin can safely protect against the development of pathological angiogenesis and promote its regression. We generated and purified recombinant human opticin and investigated its impact on the development and regression of pathological retinal neovascularization following intravitreal administration in murine oxygen-induced retinopathy. We also investigated its effect on normal retinal vascular development and function, following intravitreal injection in neonatal mice, by histological examination and electroretinography. In oxygen-induced retinopathy, intravitreal administration of human recombinant opticin protected against the development of retinal neovascularization to similar extent as aflibercept, which targets VEGF. Opticin also accelerated regression of established retinal neovascularization, though the effect at 18 h was less than that of aflibercept. Intravitreal administration of human recombinant opticin in neonatal mice caused no detectable perturbation of subsequent retinal vascular development or function. In summary we found that intraocular administration of recombinant human opticin protects against the development of pathological angiogenesis in mice and promotes its regression.

Expanding the Scope of the Visit: Which Patient-Initiated Additional Concerns Receive Help?

This study examines patient-initiated additional concern presentations in general surgery visits to assess which factors contribute to them getting "helped." Concern presentations were analyzed for a variety of design features (e.g., social action (inquiry vs. informing), when patients initiate during a visit, how patients fit topic to previous talk or activity) and contextual factors (e.g., concern falls inside or outside surgeon's domain of expertise, chronic vs. acute concern-types, the history of the patient-physician relationship). This study uses a mixed-methods approach, combining case-level conversation analysis and aggregate-level statistical analysis. Data are video recordings of office visits from 2013-2015, with a longitudinal focus of following the same patients across time. In total, 62 patients spanning 175 visits were analyzed. 377 patient-initiated additional concerns were found, and 188 received help. Several factors were found to increase the likelihood of patients' concerns getting helped such as designing the concern as an inquiry, raising the concern early in the visit, and mentioning the concern more than once. These findings can help guide patients on how to better design additional concerns presentations to receive help and can benefit physicians by identifying more subtle practices patients are already using to broach concerns to help reduce unnoticed or unhelped concerns.

A Comparison of the Spatial Arrangement Method and the Total-Set Pairwise Rating Method for Obtaining Similarity Data in the Conceptual Domain.

We compare two methods for obtaining similarity data in the conceptual domain. In the Spatial Arrangement Method (SpAM), participants organize stimuli on a computer screen so that the distance between stimuli represents their perceived dissimilarity. In Total-Set Pairwise Rating Method (PRaM), participants rate the (dis)similarity of all pairs of stimuli on a Likert scale. In each of three studies, we had participants indicate the similarity of four sets of conceptual stimuli with either PRaM or SpAM. Studies 1 and 2 confirm two caveats that have been raised for SpAM. (i) While SpAM takes significantly less time to complete than PRaM, it yields less reliable data than PRaM does. (ii) Because of the spatial manner in which similarity is measured in SpAM, the method is biased against feature representations. Despite these differences, averaging SpAM and PRaM dissimilarity data across participants yields comparable aggregate data. Study 3 shows that by having participants only judge half of the pairs in PRaM, its duration can be significantly reduced, without affecting the dissimilarity distribution, but at the cost of a smaller reliability. Having participants arrange multiple subsets of the stimuli does not do away with the spatial bias of SpAM.

Making Conversation Analysis Accessible: A Conceptual Guide for Health Services Researchers.

The quality of healthcare communication can impact both experiences and outcomes. We highlight aspects of communication that can be systematically examined using Conversation Analysis (CA) and provide guidance about how researchers can incorporate CA into healthcare studies. CA is a qualitative method for studying naturally occurring communication by analyzing recurrent, systematic practices of verbal and nonverbal behavior. CA involves examining audio- or video-recorded conversations and their transcriptions to identify practices speakers use to communicate and interpret behavior. We explain what distinguishes CA from other methods that study communication and highlight three accessible CA approaches that researchers can use in their research design, analysis, or implementation of communication interventions. Specifically, these approaches focus on how talk is produced (specific words, framing, and syntax), by whom, and when it occurs in the conversation. These approaches can be leveraged to generate hypotheses and to identify patterns of behavior that inform empirically driven communication interventions.

Agenda setting and visit openings in primary care visits involving patients taking opioids for chronic pain.

BACKGROUND: Agenda setting is associated with more efficient care and better patient experience. This study develops a taxonomy of visit opening styles to assess use of agenda and non-agenda setting visit openings and their effects on participant experience. METHODS: This observational study analyzed 83 video recorded US primary care visits at a single academic medical center in California involving family medicine and internal medicine resident physicians (n = 49) and patients (n = 83) with chronic pain on opioids. Using conversation analysis, we developed a coding scheme that assessed the presence of agenda setting, distinct visit opening styles, and the number of total topics, major topics, surprise patient topics, and returns to prior topics discussed. Exploratory quantitative analyses were conducted to assess the relationship of agenda setting and visit opening styles with post-visit measures of both patient experience and physician perception of visit difficulty. RESULTS: We identified 2 visit opening styles representing agenda setting (agenda eliciting, agenda reframing) and 3 non-agenda setting opening styles (open-ended question, patient launch, physician launch). Agenda setting was only performed in 11% of visits and was associated with fewer surprise patient topics than visits without agenda setting (mean (SD) 2.67 (1.66) versus 4.28 (3.23), p = 0.03). CONCLUSIONS: In this study of patients with chronic pain, resident physicians rarely performed agenda setting, whether defined in terms of "agenda eliciting" or "agenda re-framing." Agenda setting was associated with fewer surprise topics. Understanding the communication context and outcomes of agenda setting may inform better use of this communication tool in primary care  practice.

"It Sometimes Doesn't Even Work": Patient Opioid Assessments as Clues to Therapeutic Flexibility in Primary Care.

BACKGROUND: Physicians' fear of difficult patient interactions is an important barrier to discontinuing long-term opioid therapy. OBJECTIVE: To identify patient statements about opioids that indicate potential openness to tapering opioids or trying non-opioid pain treatments DESIGN: This is an observational study of regularly scheduled primary care visits involving discussion of chronic pain management. A coding system to characterize patient assessments about opioids, physician responses to assessments, and patient-endorsed opioid side effects was developed and applied to transcripts of video-recorded visits. All visits were independently coded by 2 authors. PARTICIPANTS: Eighty-six established adult patients taking opioids for chronic pain; 49 physicians in 2 academic primary care clinics MAIN MEASURES: Frequency and topic of patients' opioid assessments; proportion of opioid assessments classified as clues (assessments indicating potential willingness to consider non-opioid pain treatments or lower opioid doses); physician responses to patient clues; frequency and type of patient-endorsed side effects KEY RESULTS: Patients made a mean of 3.2 opioid assessments (median 2) per visit. The most common assessment topics were pain relief (51%), effect on function (21%), and opioid safety (14%). Forty-seven percent of opioid assessments (mean 1.5 per visit) were classified as clues. Fifty-three percent of visits included ≥ 1 clue; 21% of visits contained ≥ 3 clues. Physicians responded to patient clues with no/minimal response 43% of the time, sympathetic/empathetic statements 14% of the time, and further explored clues 43% of the time. Fifty-eight percent of patients endorsed ≥ 1 opioid-related side effect; 10% endorsed ≥ 3 side effects. The most commonly endorsed side effects were constipation (15% of patients), sedation (15%), withdrawal symptoms (13%), and nausea (12%). CONCLUSIONS: Patient statements suggesting openness to non-opioid pain treatments or lower opioid doses are common during routine primary care visits. Listening for and exploring these clues may be a patient-centered strategy for broaching difficult topics with patients on long-term opioid therapy.

Intravitreal Pharmacokinetic Study of the Antiangiogenic Glycoprotein Opticin.

Opticin is an endogenous vitreous glycoprotein that may have therapeutic potential as it has been shown that supranormal concentrations suppress preretinal neovascularization. Herein we investigated the pharmacokinetics of opticin following intravitreal injection in rabbits. To measure simultaneously concentrations of human and rabbit opticin, a selected reaction monitoring mass spectrometry assay was developed. The mean concentration of endogenous rabbit opticin in 7 uninjected eyes was measured and found to be 19.2 nM or 0.62 µg/mL. When the vitreous was separated by centrifugation into a supernatant and collagen-containing pellet, 94% of the rabbit opticin was in the supernatant. Intravitreal injection of human opticin (40 µg) into both eyes of rabbits was followed by enucleation at 5, 24, and 72 h and 7, 14, and 28 days postinjection (n = 6 at each time point) and measurement of vitreous human and rabbit opticin concentrations in the supernatant and collagen-containing pellet following centrifugation. The volume of distribution of human opticin was calculated to be 3.31 mL, and the vitreous half-life was 4.2 days. Assuming that rabbit and human opticin are cleared from rabbit vitreous at the same rate, opticin is secreted into the vitreous at a rate of 0.14 µg/day. We conclude that intravitreally injected opticin has a vitreous half-life that is similar to currently available antiangiogenic therapeutics. While opticin was first identified bound to vitreous collagen fibrils, here we demonstrate that >90% of endogenous opticin is not bound to collagen. Endogenous opticin is secreted by the nonpigmented ciliary epithelium into the rabbit vitreous at a remarkably high rate, and the turnover in vitreous is approximately 15% per day.

A case study of a collaborative allied health and nursing crisis response.

The COVID-19 pandemic was declared by the World Health Organization on 11 March 2020. The rapid spread of SARS-CoV-2 required an equally rapid response from health-care organizations to find innovative ways to utilize the existing workforce to care for people with COVID-19. Using an evaluative case study, a unique insight into the collaborative allied health and nursing professions' response to COVID-19 at a specialist cardiothoracic hospital in the United Kingdom is presented. The aim of the case study was to evaluate how an interprofessional workforce from the wider organization could be supported to work in critical care as part of a crisis response. In identifying the key enablers to setting up an interprofessional Essential Care Team and learning from the lived experiences of those involved, this case study has demonstrated that, in supported, interprofessional teams the wider organizational workforce can be facilitated to effectively and safely provide critical care services. The lessons learned from this study will support future pandemic responses and aid the identification of further opportunities for interprofessional learning and practice. Ultimately, the study highlights that by identifying and investing in the key enablers, health-care organizations can be better prepared to respond to a global crisis.

Novel carbonic anhydrase IX-targeted therapy enhances the anti-tumour effects of cisplatin in small cell lung cancer.

Small cell lung cancer (SCLC) has an extremely poor prognosis and methods of improving chemotherapeutic intervention are much sought after. A promising approach lies in inhibiting the tumour-associated enzyme, carbonic anhydrase IX (CA IX), which supports tumour cell survival. The aim of this study was to assess the potential of CA IX inhibition using 4-(3'-(3″,5″-dimethylphenyl)ureido)phenyl sulfamate (S4), for the treatment of human SCLC alone and in combination with cisplatin chemotherapy. Treating SCLC cell lines (DMS 79 and COR-L24) with 100 µM S4 reduced viability in vitro and enhanced cell death when combined with 7 µM cisplatin, most prominently under hypoxic conditions (0.1% O2 ). When either cell line was grown as a xenograft tumour in nude mice, intraperitoneal injection of 50 mg/kg S4 alone and in combination with 3 mg/kg cisplatin led to significantly reduced tumour growth. Combination therapy was superior to single agents and response was greatly accentuated when administering repeated doses of cisplatin in DMS 79 tumours. The mechanism of therapeutic response was investigated in vitro, where S4 treatment increased apoptosis under hypoxic conditions in both DMS 79 and COR-L24 cells. DMS 79 tumours receiving S4 in vivo also displayed increased apoptosis and necrosis. Combining S4 with cisplatin reduced both the area of hypoxia and CA IX-positive cells within tumours and increased necrosis, suggesting hypoxia-specific targeting. This study presents a novel, targeted approach to improving current SCLC therapy via inhibition of CA IX, which enhances apoptosis and significantly inhibits xenograft tumour growth when administered alone and in combination with cisplatin chemotherapy.

Maternal overnutrition programs epigenetic changes in the regulatory regions of hypothalamic Pomc in the offspring of rats.

BACKGROUND AND OBJECTIVE: Maternal overnutrition has been implicated in affecting the offspring by programming metabolic disorders such as obesity and diabetes, by mechanisms that are not clearly understood. This study aimed to determine the long-term impact of maternal high-fat (HF) diet feeding on epigenetic changes in the offspring's hypothalamic Pomc gene, coding a key factor in the control of energy balance. Further, it aimed to study the additional effects of postnatal overnutrition on epigenetic programming by maternal nutrition. METHODS: Eight-week-old female Sprague-Dawley rats were fed HF diet or low-fat (LF) diet for 6 weeks before mating, and throughout gestation and lactation. At postnatal day 21, samples were collected from a third offspring and the remainder were weaned onto LF diet for 5 weeks, after which they were either fed LF or HF diet for 12 weeks, resulting in four groups of offspring differing by their maternal and postweaning diet. RESULTS: With maternal HF diet, offspring at weaning had rapid early weight gain, increased adiposity, and hyperleptinemia. The programmed adult offspring, subsequently fed LF diet, retained the increased body weight. Maternal HF diet combined with offspring HF diet caused more pronounced hyperphagia, fat mass, and insulin resistance. The ARC Pomc gene from programmed offspring at weaning showed hypermethylation in the enhancer (nPE1 and nPE2) regions and in the promoter sequence mediating leptin effects. Interestingly, hypermethylation at the Pomc promoter but not at the enhancer region persisted long term into adulthood in the programmed offspring. However, there were no additive effects on methylation levels in the regulatory regions of Pomc in programmed offspring fed a HF diet. CONCLUSION: Maternal overnutrition programs long-term epigenetic alterations in the offspring's hypothalamic Pomc promoter. This predisposes the offspring to metabolic disorders later in life.

International survey on high- and low-dose synacthen test and assessment of accuracy in preparing low-dose synacthen.

OBJECTIVE: The short synacthen test (SST) is widely used to assess patients for adrenal insufficiency, but the frequency and protocols used across different centres for the low-dose test (LDT) are unknown. This study aimed to survey centres and test the accuracy of ten different synacthen preparation strategies used for the LDT. METHODS: Members of 6 international endocrine societies were surveyed regarding diagnostic tests used for adrenal insufficiency, and in particular the SST. Synacthen was diluted for the LDT and concentrations measured using a synacthen ELISA. RESULTS: Survey responses were received from 766 individuals across 60 countries (52% adult, 45% paediatric endocrinologists). The SST is used by 98% of centres: 92% using high-dose (250 µg), 43% low-dose and 37% both. Ten low-dose dilution methods were assessed and variation in synacthen concentration was demonstrated with intramethod coefficients of variation (CV) ranging from 2.1% to 109%. The method using 5% dextrose as a diluent was the least variable (CV of 2.1%). The variation in dilution methods means that the dose of synacthen administered in a LDT may vary between 0.16 and 0.81 µg. CONCLUSIONS: The high-dose SST is the most popular diagnostic test of adrenal insufficiency, but up to 72% of paediatric endocrinologists use a LDT. There is considerable variation observed both within and between low-dose synacthen dilution methods creating considerable risk of inaccurate dosing and thereby invalid results.

Evaluation of CSF and plasma biomarkers of brain melanocortin activity in response to caloric restriction in humans.

The melanocortin neuronal system, which consists of hypothalamic proopiomelanocortin (POMC) and agouti-related protein (AgRP) neurons, is a leptin target that regulates energy balance and metabolism, but studies in humans are limited by a lack of reliable biomarkers to assess brain melanocortin activity. The objective of this study was to measure the POMC prohormone and its processed peptide, ß-endorphin (ß-EP), in cerebrospinal fluid (CSF) and AgRP in CSF and plasma after calorie restriction to validate their utility as biomarkers of brain melanocortin activity. CSF and plasma were obtained from 10 lean and obese subjects after fasting (40 h) and refeeding (24 h), and from 8 obese subjects before and after 6 wk of dieting (800 kcal/day) to assess changes in neuropeptide and hormone levels. After fasting, plasma leptin decreased to 35%, and AgRP increased to 153% of baseline. During refeeding, AgRP declined as leptin increased; CSF ß-EP increased, but POMC did not change. Relative changes in plasma and CSF leptin were blunted in obese subjects. After dieting, plasma and CSF leptin decreased to 46% and 70% of baseline, CSF POMC and ß-EP decreased, and plasma AgRP increased. At baseline, AgRP correlated negatively with insulin and homeostasis model assessment (HOMA-IR), and positively with the Matsuda index. Thus, following chronic calorie restriction, POMC and ß-EP declined in CSF, whereas acutely, only ß-EP changed. Plasma AgRP, however, increased after both acute and chronic calorie restriction. These results support the use of CSF POMC and plasma AgRP as biomarkers of hypothalamic melanocortin activity and provide evidence linking AgRP to insulin sensitivity.

Identification of TRIM27 as a novel degradation target of herpes simplex virus 1 ICP0.

UNLABELLED: The herpes simplex virus 1 (HSV-1) immediate early protein ICP0 performs many functions during infection, including transactivation of viral gene expression, suppression of innate immune responses, and modification and eviction of histones from viral chromatin. Although these functions of ICP0 have been characterized, the detailed mechanisms underlying ICP0's complex role during infection warrant further investigation. We thus undertook an unbiased proteomic approach to identifying viral and cellular proteins that interact with ICP0 in the infected cell. Cellular candidates resulting from our analysis included the ubiquitin-specific protease USP7, the transcriptional repressor TRIM27, DNA repair proteins NBN and MRE11A, regulators of apoptosis, including BIRC6, and the proteasome. We also identified two HSV-1 early proteins involved in nucleotide metabolism, UL39 and UL50, as novel candidate interactors of ICP0. Because TRIM27 was the most statistically significant cellular candidate, we investigated the relationship between TRIM27 and ICP0. We observed rapid, ICP0-dependent loss of TRIM27 during HSV-1 infection. TRIM27 protein levels were restored by disrupting the RING domain of ICP0 or by inhibiting the proteasome, arguing that TRIM27 is a novel degradation target of ICP0. A mutant ICP0 lacking E3 ligase activity interacted with endogenous TRIM27 during infection as demonstrated by reciprocal coimmunoprecipitation and supported by immunofluorescence data. Surprisingly, ICP0-null mutant virus yields decreased upon TRIM27 depletion, arguing that TRIM27 has a positive effect on infection despite being targeted for degradation. These results illustrate a complex interaction between TRIM27 and viral infection with potential positive or negative effects of TRIM27 on HSV under different infection conditions. IMPORTANCE: During productive infection, a virus must simultaneously redirect multiple cellular pathways to replicate itself while evading detection by the host's defenses. To orchestrate such complex regulation, viruses, including herpes simplex virus 1 (HSV-1), rely on multifunctional proteins such as the E3 ubiquitin ligase ICP0. This protein regulates various cellular pathways concurrently by targeting a diverse set of cellular factors for degradation. While some of these targets have been previously identified and characterized, we undertook a proteomic screen to identify additional targets of this activity to further characterize ICP0's role during infection. We describe a set of candidate interacting proteins of ICP0 identified through this approach and our characterization of the most statistically significant result, the cellular transcriptional repressor TRIM27. We present TRIM27 as a novel degradation target of ICP0 and describe the relationship of these two proteins during infection.

Diagnostic yield of molecular autopsy in patients with sudden arrhythmic death syndrome using targeted exome sequencing.

AIMS: The targeted genetic screening of Sudden Arrhythmic Death Syndrome (SADS) probands in a molecular autopsy has a diagnostic yield of up to 35%. Exome sequencing has the potential to improve this yield. The primary aim of this study is to examine the feasibility and diagnostic utility of targeted exome screening in SADS victims, utilizing familial clinical screening whenever possible. METHODS AND RESULTS: To determine the feasibility and diagnostic yield of targeted exome sequencing deoxyribonucleic acid (DNA) was isolated from 59 SADS victims (mean age 25 years, range 1-51 years). Targeted exome sequencing of 135 genes associated with cardiomyopathies and ion channelopathies was performed on the Illumina HiSeq2000 platform. Non-synonymous, loss-of-function, and splice-site variants with a minor allele frequency <0.02% in the NHLBI exome sequencing project and an internal set of control exomes were prioritized for analysis followed by <0.5% frequency threshold secondary analysis. First-degree relatives were offered clinical screening for inherited cardiac conditions. Seven probands (12%) carried very rare (<0.02%) or novel non-sense candidate mutations and 10 probands (17%) had previously published rare (0.02-0.5%) candidate mutations-a total yield of 29%. Co-segregation fully confirmed two private SCN5A Na channel mutations. Variants of unknown significance were detected in a further 34% of probands. CONCLUSION: Molecular autopsy using targeted exome sequencing has a relatively low diagnostic yield of very rare potentially disease causing mutations. Candidate pathogenic variants with a higher frequency in control populations are relatively common and should be interpreted with caution.

Identification of factor H-like protein 1 as the predominant complement regulator in Bruch's membrane: implications for age-related macular degeneration.

The tight regulation of innate immunity on extracellular matrix (ECM) is a vital part of immune homeostasis throughout the human body, and disruption to this regulation in the eye is thought to contribute directly to the progression of age-related macular degeneration (AMD). The plasma complement regulator factor H (FH) is thought to be the main regulator that protects ECM against damaging complement activation. However, in the present study we demonstrate that a truncated form of FH, called FH-like protein 1 (FHL-1), is the main regulatory protein in the layer of ECM under human retina, called Bruch's membrane. Bruch's membrane is a major site of AMD disease pathogenesis and where drusen, the hallmark lesions of AMD, form. We show that FHL-1 can passively diffuse through Bruch's membrane, whereas the full sized, glycosylated, FH cannot. FHL-1 is largely bound to Bruch's membrane through interactions with heparan sulfate, and we show that the common Y402H polymorphism in the CFH gene, associated with an increased risk of AMD, reduces the binding of FHL-1 to this heparan sulfate. We also show that FHL-1 is retained in drusen whereas FH coats the periphery of the lesions, perhaps inhibiting their clearance. Our results identify a novel mechanism of complement regulation in the human eye, which highlights potential new avenues for therapeutic strategies.

Learning Styles: Impact on Knowledge and Confidence in Nursing Students in Simulation and Classroom.

Nurse Educators must develop nursing curriculum with engaging learning strategies that promote the knowledge and confidence needed for safe, effective nursing practice. Faculty should explore new methods of teaching that consider how students learn. Studies have shown mixed results regarding student learning styles, academic achievement, and development of confidence in nursing practice. An experimental study using Felder and Soloman's (2004). Index of learning styles instrument was conducted to examine nursing student learning styles and their impact on confidence and knowledge in traditional and high fidelity simulation settings. Findings revealed students were more likely to have active, visual, sensing, and sequential learning styles. Student confidence or knowledge did not significantly differ among the learning styles in either simulation or traditional classroom methods. Awareness of learning styles may aid faculty in adapting engaging teaching strategies. Further research is needed with larger samples to identify best approaches to enhance student learning within the context of learning styles.