IL-13-associated epithelial remodeling correlates with clinical severity in nasal polyposis.

BACKGROUND: Epithelial remodeling is a histopathologic feature of chronic inflammatory airway diseases including chronic rhinosinusitis (CRS). Cell-type shifts and their relationship to CRS endotypes and severity are incompletely described. OBJECTIVE: We sought to understand the relationship of epithelial cell remodeling to inflammatory endotypes and disease outcomes in CRS. METHODS: Using cell-type transcriptional signatures derived from epithelial single-cell sequencing, we analyzed bulk RNA-sequencing data from sinus epithelial brushings obtained from patients with CRS with and without nasal polyps in comparison to healthy controls. RESULTS: The airway epithelium in nasal polyposis displayed increased tuft cell transcripts and decreased ciliated cell transcripts along with an IL-13 activation signature. In contrast, CRS without polyps showed an IL-17 activation signature. IL-13 activation scores were associated with increased tuft cell, goblet cell, and mast cell scores and decreased ciliated cell scores. Furthermore, the IL-13 score was strongly associated with a previously reported activated ("polyp") tuft cell score and a prostaglandin E2 activation signature. The Lund-Mackay score, a computed tomographic metric of sinus opacification, correlated positively with activated tuft cell, mast cell, prostaglandin E2, and IL-13 signatures and negatively with ciliated cell transcriptional signatures. CONCLUSIONS: These results demonstrate that cell-type alterations and prostaglandin E2 stimulation are key components of IL-13-induced epithelial remodeling in nasal polyposis, whereas IL-17 signaling is more prominent in CRS without polyps, and that clinical severity correlates with the degree of IL-13-driven epithelial remodeling.

Multistep peripherin-2/rds self-assembly drives membrane curvature for outer segment disk architecture and photoreceptor viability.

Rod and cone photoreceptor outer segment (OS) structural integrity is essential for normal vision; disruptions contribute to a broad variety of retinal ciliopathies. OSs possess many hundreds of stacked membranous disks, which capture photons and scaffold the phototransduction cascade. Although the molecular basis of OS structure remains unresolved, recent studies suggest that the photoreceptor-specific tetraspanin, peripherin-2/rds (P/rds), may contribute to the highly curved rim domains at disk edges. Here, we demonstrate that tetrameric P/rds self-assembly is required for generating high-curvature membranes in cellulo, implicating the noncovalent tetramer as a minimal unit of function. P/rds activity was promoted by disulfide-mediated tetramer polymerization, which transformed localized regions of curvature into high-curvature tubules of extended lengths. Transmission electron microscopy visualization of P/rds purified from OS membranes revealed disulfide-linked tetramer chains up to 100 nm long, suggesting that chains maintain membrane curvature continuity over extended distances. We tested this idea in Xenopus laevis photoreceptors, and found that transgenic expression of nonchain-forming P/rds generated abundant high-curvature OS membranes, which were improperly but specifically organized as ectopic incisures and disk rims. These striking phenotypes demonstrate the importance of P/rds tetramer chain formation for the continuity of rim formation during disk morphogenesis. Overall, this study advances understanding of the normal structure and function of P/rds for OS architecture and biogenesis, and clarifies how pathogenic loss-of-function mutations in P/rds cause photoreceptor structural defects to trigger progressive retinal degenerations. It also introduces the possibility that other tetraspanins may generate or sense membrane curvature in support of diverse biological functions.

Total Ankle Replacement Versus Arthrodesis for End-Stage Ankle Osteoarthritis: A Randomized Controlled Trial.

BACKGROUND: End-stage ankle osteoarthritis causes severe pain and disability. There are no randomized trials comparing the 2 main surgical treatments: total ankle replacement (TAR) and ankle fusion (AF). OBJECTIVE: To determine which treatment is superior in terms of clinical scores and adverse events. DESIGN: A multicenter, parallel-group, open-label randomized trial. (ISRCTN registry number: 60672307). SETTING: 17 National Health Service trusts across the United Kingdom. PATIENTS: Patients with end-stage ankle osteoarthritis, aged 50 to 85 years, and suitable for either procedure. INTERVENTION: Patients were randomly assigned to TAR or AF surgical treatment. MEASUREMENTS: The primary outcome was change in Manchester-Oxford Foot Questionnaire walking/standing (MOXFQ-W/S) domain scores between baseline and 52 weeks after surgery. No blinding was possible. RESULTS: Between 6 March 2015 and 10 January 2019, a total of 303 patients were randomly assigned; mean age was 68 years, and 71% were men. Twenty-one patients withdrew before surgery, and 281 clinical scores were analyzed. At 52 weeks, the mean MOXFQ-W/S scores improved for both groups. The adjusted difference in the change in MOXFQ-W/S scores from baseline was -5.6 (95% CI, -12.5 to 1.4), showing that TAR improved more than AF, but the difference was not considered clinically or statistically significant. The number of adverse events was similar between groups (109 vs. 104), but there were more wound healing issues in the TAR group and more thromboembolic events and nonunion in the AF group. The symptomatic nonunion rate for AF was 7%. A post hoc analysis suggested superiority of fixed-bearing TAR over AF (-11.1 [CI, -19.3 to -2.9]). LIMITATION: Only 52-week data; pragmatic design creates heterogeneity of implants and surgical techniques. CONCLUSION: Both TAR and AF improve MOXFQ-W/S and had similar clinical scores and number of harms. Total ankle replacement had greater wound healing complications and nerve injuries, whereas AF had greater thromboembolism and nonunion, with a symptomatic nonunion rate of 7%. PRIMARY FUNDING SOURCE: National Institute for Health and Care Research Heath Technology Assessment Programme.

Loss of MPC1 reprograms retinal metabolism to impair visual function.

Glucose metabolism in vertebrate retinas is dominated by aerobic glycolysis (the "Warburg Effect"), which allows only a small fraction of glucose-derived pyruvate to enter mitochondria. Here, we report evidence that the small fraction of pyruvate in photoreceptors that does get oxidized by their mitochondria is required for visual function, photoreceptor structure and viability, normal neuron-glial interaction, and homeostasis of retinal metabolism. The mitochondrial pyruvate carrier (MPC) links glycolysis and mitochondrial metabolism. Retina-specific deletion of MPC1 results in progressive retinal degeneration and decline of visual function in both rod and cone photoreceptors. Using targeted-metabolomics and 13C tracers, we found that MPC1 is required for cytosolic reducing power maintenance, glutamine/glutamate metabolism, and flexibility in fuel utilization.

Subtalar joint middle facet agenesis: a case report and literature review.

Articular facet morphology plays a fundamental role in subtalar joint biomechanics and stability, and likely influences the development of hindfoot osteoarthritis. While multiple anatomical studies have shown wide variation in articular facet configuration, the clinico-radiological findings are rarely presented. We illustrate a case of bilateral subtalar joint middle facet agenesis in a 45-year-old woman, which was missed despite several presentations. We demonstrate the imaging findings to enable clinicians to distinguish this from the more common middle facet coalition. We summarise the developmental anatomy and discuss the potential implications on biomechanical function. Recognition of middle facet agenesis within the complex subtalar joint is important to prevent misdiagnosis and unnecessary surgery.

Ankle Arthritis Networking: Getting the right treatment to the right patient first time.

End stage ankle joint arthritis is a debilitating condition. Surgical treatment, most commonly ankle arthrodesis or fusion, can be highly effective. The authors outline the nature and prevalence of ankle arthritis and show that the frequency of each type of procedure varies geographically. They present data supporting the hypothesis that units performing ankle replacement more frequently tend to have better outcomes, both clinically and financially. Adoption of country-wide Ankle Arthritis Networks is proposed, ensuring that every patient seeing a foot and ankle orthopaedic surgeon has potential access to all treatment options whether their surgeon chooses to perform replacement or not. The case is made that establishment of Ankle Arthritis Networks will avoid the need for units to perform a low number of replacements per year, homogenise treatment availability across the country and enables the right patient to receive the right treatment first time. LEVEL OF EVIDENCE: IV.

ARL13B, a Joubert Syndrome-Associated Protein, Is Critical for Retinogenesis and Elaboration of Mouse Photoreceptor Outer Segments.

Mutations in the Joubert syndrome-associated small GTPase ARL13B are linked to photoreceptor impairment and vision loss. To determine the role of ARL13B in the development, function, and maintenance of ciliated photoreceptors, we generated a pan-retina knock-out (Six3-Cre) and a rod photoreceptor-specific inducible conditional knock-out (Pde6g-CreERT2) of ARL13B using murine models. Embryonic deletion of ARL13B led to defects in retinal development with reduced cell proliferation. In the absence of ARL13B, photoreceptors failed to develop outer segment (OS) membranous discs and axonemes, resulting in loss of function and rapid degeneration. Additionally, the majority of photoreceptor basal bodies did not dock properly at the apical edge of the inner segments. The removal of ARL13B in adult rod photoreceptor cells after maturation of OS resulted in loss of photoresponse and vesiculation in the OS. Before changes in photoresponse, removal of ARL13B led to mislocalization of rhodopsin, prenylated phosphodiesterase-6 (PDE6), and intraflagellar transport protein-88 (IFT88). Our findings show that ARL13B is required at multiple stages of retinogenesis, including early postnatal proliferation of retinal progenitor cells, development of photoreceptor cilia, and morphogenesis of photoreceptor OS discs regardless of sex. Last, our results establish a need for ARL13B in photoreceptor maintenance and protein trafficking.SIGNIFICANCE STATEMENT The normal development of photoreceptor cilia is essential to create functional, organized outer segments with stacked membrane discs that house the phototransduction proteins necessary for sight. Our study identifies a complex role for ARL13B, a small GTPase linked to Joubert syndrome and visual impairment, at various stages of photoreceptor development. Loss of ARL13B led to defects in retinal proliferation, altered placement of basal bodies crucial for components of the cilium (transition zone) to emanate, and absence of photoreceptor-stacked discs. These defects led to extinguished visual response and dysregulated protein trafficking. Our findings show the complex role ARL13B plays in photoreceptor development, viability, and function. Our study accounts for the severe retinal impairment observed in ARL13B-linked Joubert syndrome patients.

Bardet-Biedl syndrome-8 (BBS8) protein is crucial for the development of outer segments in photoreceptor neurons.

Bardet-Biedl syndrome (BBS) is an autosomal recessive ciliopathy characterized by developmental abnormalities and vision loss. To date, mutations in 21 genes have been linked to BBS. The products of eight of these BBS genes form a stable octameric complex termed the BBSome. Mutations in BBS8, a component of the BBSome, cause early vision loss, but the role of BBS8 in supporting vision is not known. To understand the mechanisms by which BBS8 supports rod and cone photoreceptor function, we generated animal models lacking BBS8. The loss of BBS8 protein led to concomitant decrease in the levels of BBSome subunits, BBS2 and BBS5 and increase in the levels of the BBS1 and BBS4 subunits. BBS8 ablation was associated with severe reduction of rod and cone photoreceptor function and progressive degeneration of each photoreceptor subtype. We observed disorganized and shortened photoreceptor outer segments (OS) at post-natal day 10 as the OS elaborates. Interestingly, loss of BBS8 led to changes in the distribution of photoreceptor axonemal proteins and hyper-acetylation of ciliary microtubules. In contrast to properly localized phototransduction machinery, we observed OS accumulation of syntaxin3, a protein normally found in the cytoplasm and the synaptic termini. In conclusion, our studies demonstrate the requirement for BBS8 in early development and elaboration of ciliated photoreceptor OS, explaining the need for BBS8 in normal vision. The findings from our study also imply that early targeting of both rods and cones in BBS8 patients is crucial for successful restoration of vision.

Asymptomatic carotid stenosis is associated with mobility and cognitive dysfunction and heightens falls in older adults.

BACKGROUND: Atherosclerosis of the carotid bifurcation with plaque formation causes asymptomatic carotid artery stenosis (ACAS), which may also be associated with cerebral hypoperfusion. Cerebral hypoperfusion adversely affects multiple aspects of mobility and cognition. This study tests the hypothesis that community-dwelling older adults with a 50% or greater diameter-reducing ACAS will have mobility and cognitive impairments that heighten their risk for falls. METHODS: Eighty community-dwelling adults completed a mobility assessment (Short Physical Performance Battery, Berg Balance Scale, Four Square Step Test, Dynamic Gait Index, Timed Up and Go, and gait speed), self-reported physical function (Activities-Specific Balance Confidence, SF-12 Physical Function Component), and cognitive tests (Mini-Mental State Examination). Falls were recorded for the past 6 months. Standardized carotid ultrasound examination classified participants into no stenosis (<50% diameter reduction) (n = 54), moderate stenosis (50%-69%) (n = 17), and high-grade stenosis (70%-99%) (n = 9) groups. Linear and logistic regression analyses determined the associations between these measures and the degree of stenosis (three groups). RESULTS: Logistic regression analysis showed their degree of stenosis was associated with reductions in mobility (Short Physical Performance Battery [P = .008], Berg Balance Scale [P = .0008], Four Square Step Test [P = .005], DGI [P = .0001], TUG [P = .0004], gait speed [P = .02]), perceived physical function (ABC [P < .0001], SF-12 Physical Function Component [P < .0001]), and cognition (MMSE [P = .003]). Adults with moderate- and high-grade stenosis had a greater incidence of falls compared with those without stenosis (relative risk, 2.86; P = .01). Results remained unchanged after adjustment for age, sex and cardiovascular risk factors. CONCLUSIONS: ACAS is associated with impaired mobility and cognition that are accompanied with increased fall risk. These impairments increased with worsening severity.

Regulation of hepatic autophagy by stress-sensing transcription factor CREBH.

Autophagy, a lysosomal degradative pathway in response to nutrient limitation, plays an important regulatory role in lipid homeostasis upon energy demands. Here, we demonstrated that the endoplasmic reticulum-tethered, stress-sensing transcription factor cAMP-responsive element-binding protein, hepatic-specific (CREBH) functions as a major transcriptional regulator of hepatic autophagy and lysosomal biogenesis in response to nutritional or circadian signals. CREBH deficiency led to decreased hepatic autophagic activities and increased hepatic lipid accumulation upon starvation. Under unfed or during energy-demanding phases of the circadian cycle, CREBH is activated to drive expression of the genes encoding the key enzymes or regulators in autophagosome formation or autophagic process, including microtubule-associated protein 1B-light chain 3, autophagy-related protein (ATG)7, ATG2b, and autophagosome formation Unc-51 like kinase 1, and the genes encoding functions in lysosomal biogenesis and homeostasis. Upon nutrient starvation, CREBH regulates and interacts with peroxisome proliferator-activated receptor α (PPARα) and PPARγ coactivator 1α to synergistically drive expression of the key autophagy genes and transcription factor EB, a master regulator of lysosomal biogenesis. Furthermore, CREBH regulates rhythmic expression of the key autophagy genes in the liver in a circadian-dependent manner. In summary, we identified CREBH as a key transcriptional regulator of hepatic autophagy and lysosomal biogenesis for the purpose of maintaining hepatic lipid homeostasis under nutritional stress or circadian oscillation.-Kim, H., Williams, D., Qiu, Y., Song, Z., Yang, Z., Kimler, V., Goldberg, A., Zhang, R., Yang, Z., Chen, X., Wang, L., Fang, D., Lin, J. D., Zhang, K. Regulation of hepatic autophagy by stress-sensing transcription factor CREBH.

Knowledge retention after simulated crisis: importance of independent practice and simulated mortality.

BACKGROUND: Simulation is an important component of postgraduate medical education, but optimal parameters for simulation are not known. Managing simulations independently and allowing simulated morbidity and mortality have been shown to improve follow-up performance in simulation. We hypothesised that allowing simulated mortality improves performance in follow-up simulations more than independent practice. METHODS: Using a randomised, controlled, observer-blinded design, 48 first-year residents in anaesthesia were exposed to a hyperkalaemia scenario. Subjects were divided into two groups (n=24) that allowed for independent practice or support from an attending physician. Each of these groups was then subdivided into two groups (n=12) that allowed for simulated mortality or did not. All groups received a standardised debriefing. Six months later, the subjects returned to manage a different hyperkalaemia scenario independently with potential simulated mortality. The primary outcome was total treatment score; secondary outcomes included subjects' time to request diagnostic information, time to treatment, and simulator mortality rate. RESULTS: Subject characteristics were not statistically different. The independent practice-mortality possible group had the highest total treatment score (P=0.004), fastest time to treatment (P=0.009), and lowest mortality rate (P=0.002) compared with all groups. Two-way analysis of variance and least-squares means were calculated for each combination of variables. The overall practice effect was contrasted to the potential for mortality and was insignificant; however, their interaction effect (P=0.003) was significant and produced the best results. CONCLUSIONS: Independence and the potential for simulated mortality have a greater impact on performance in follow-up simulations when combined than either factor alone.

The effects of weight bearing on the distal tibiofibular syndesmosis: A study comparing weight bearing-CT with conventional CT.

BACKGROUND: Syndesmotic injures are common and weight bearing imaging studies are often advocated to assess disruption. Although studies have examined the anatomical relationship between the fibula and incisura, the effect of weight-bearing on the syndesmosis has not been well reported. We characterise the changes which occur at the syndesmosis during weight-bearing. METHODS: In this retrospective review we analysed the position of the fibula at the syndesmosis in a cohort of patients who underwent both non-weight-bearing and weight-bearing CT scans. The relative position of the fibula to the incisura was analysed to determine translation and rotation in the axial plane. RESULTS: 26 patients were included. Comparison of measurements revealed statistically significant differences between groups which indicated that on weight-bearing the fibula translated laterally and posteriorly, and rotated externally with respect to the incisura. CONCLUSIONS: This is the first study to measure the differences in position of the syndesmosis during weight-bearing in a population of patients that have undergone both weight bearing and non weight bearing CT. Our study confirms that weight-bearing results in lateral and posterior translation, and external rotation of the fibula in relation to the incisura and our findings should help in future studies looking at the effect of weight bearing on syndesmotic pathology.

An inducible amphipathic helix within the intrinsically disordered C terminus can participate in membrane curvature generation by peripherin-2/rds.

Peripherin-2/rds is required for biogenesis of vertebrate photoreceptor outer segment organelles. Its localization at the high-curvature rim domains of outer segment disk membranes suggests that it may act to shape these structures; however, the molecular function of this protein is not yet resolved. Here, we apply biochemical, biophysical, and imaging techniques to elucidate the role(s) played by the protein's intrinsically disordered C-terminal domain and an incipient amphipathic α-helix contained within it. We investigated a deletion mutant lacking only this α-helix in stable cell lines and Xenopus laevis photoreceptors. We also studied a soluble form of the full-length ∼7-kDa cytoplasmic C terminus in cultured cells and purified from Escherichia coli The α-helical motif was not required for protein biosynthesis, tetrameric subunit assembly, tetramer polymerization, localization at disk rims, interaction with GARP2, or the generation of membrane curvature. Interestingly, however, loss of the helical motif up-regulated membrane curvature generation in cellulo, introducing the possibility that it may regulate this activity in photoreceptors. Furthermore, the incipient α-helix (within the purified soluble C terminus) partitioned into membranes only when its acidic residues were neutralized by protonation. This suggests that within the context of full-length peripherin-2/rds, partitioning would most likely occur at a bilayer interfacial region, potentially adjacent to the protein's transmembrane domains. In sum, this study significantly strengthens the evidence that peripherin-2/rds functions directly to shape the high-curvature rim domains of the outer segment disk and suggests that the protein's C terminus may modulate membrane curvature-generating activity present in other protein domains.

ARL3 regulates trafficking of prenylated phototransduction proteins to the rod outer segment.

The small GTPase, ADP-ribosylation factor-like 3 (ARL3), has been proposed to participate in the transport of proteins in photoreceptor cells. Moreover, it has been implicated in the pathogenesis associated with X-linked retinitis pigmentosa (XLRP) resulting from mutations in the ARL3 GTPase activating protein, retinitis pigmentosa 2 (RP2). To determine the importance of ARL3 in rod photoreceptor cells, we generated transgenic mice expressing a dominant active form of ARL3 (ARL3-Q71L) under a rod-specific promoter. ARL3-Q71L animals exhibited extensive rod cell death after post-natal day 30 (PN30) and degeneration was complete by PN70. Prior to the onset of cell death, rod photoresponse was significantly reduced along with a robust decrease in rod phosphodiesterase 6 (PDE6) and G-protein receptor kinase-1 (GRK1) levels. Furthermore, assembled phosphodiesterase-6 (PDE6) subunits, rod transducin and G-protein receptor kinase-1 (GRK1) accumulated on large punctate structures within the inner segment in ARL3-Q71L retina. Defective trafficking of prenylated proteins is likely due to sequestration of prenyl binding protein δ (PrBPδ) by ARL3-Q71L as we demonstrate a specific interaction between these proteins in the retina. Unexpectedly, our studies also revealed a novel role for ARL3 in the migration of photoreceptor nuclei. In conclusion, this study identifies ARL3 as a key player in prenylated protein trafficking in rod photoreceptor cells and establishes the potential role for ARL3 dysregulation in the pathogenesis of RP2-related forms of XLRP.

A Novel In Situ Simulation Intervention Used to Mitigate an Outbreak of Methicillin-Resistant Staphylococcus aureus in a Neonatal Intensive Care Unit.

OBJECTIVE: To describe the successful implementation of an in situ simulation program to diagnose and correct latent safety threats in a level 4 neonatal intensive care unit (NICU) to mitigate a methicillin-resistant Staphylococcus aureus (MRSA) outbreak. STUDY DESIGN: An investigational report describes a simulation intervention that occurred during a 4-month MRSA outbreak in a single-center, 46-bed, newly renovated level 4 NICU. The simulation program was developed for all NICU providers in which they were exposed to a 30-minute in situ human simulation intervention that included education, evaluation, and debriefing to resolve perceived or observed latent safety threats. The primary study outcome was improved hand hygiene compliance and an enhanced estimate of the culture of safety during a 6-month period. RESULTS: A total of 99 healthcare providers including physicians, nurses, respiratory therapists, and environmental service workers completed the course. Before the simulation intervention, there were 18 patients colonized or infected with a single MRSA clone; after the intervention, there were no new episodes of colonization or infection. CONCLUSIONS: An in situ, simulation-based intervention can counter threats to patient safety related to workflow and lapses in infection control practices and improve patient outcomes.

Impact of Intravenous Acetaminophen on Perioperative Opioid Utilization and Outcomes in Open Colectomies: A Claims Database Analysis.

BACKGROUND: The value of intravenous acetaminophen in postoperative pain management remains debated. The authors tested the hypothesis that intravenous acetaminophen use, in isolation and in comparison to oral, would be associated with decreased opioid utilization (clinically significant reduction defined as 25%) and opioid-related adverse effects in open colectomy patients. METHODS: Using national claims data from open colectomy patients (Premier Healthcare Database, Premier Healthcare Solutions, Inc., USA; 2011 to 2016; n = 181,640; 602 hospitals), we separately categorized oral and intravenous acetaminophen use: 1 (1,000 mg) or more than 1 dose on the day of surgery, postoperative day 1, or later. Multilevel models measured associations between intravenous or oral acetaminophen and (1) opioid utilization and (2) opioid-related adverse effects. Percent change and multiplicity-adjusted 99.5% CI are reported. RESULTS: Overall, 25.1% of patients received intravenous acetaminophen, of whom 48.0% (n = 21,878) received 1 dose on the day of surgery. In adjusted analyses, particularly more than 1 dose of intravenous acetaminophen (versus nonuse) on postoperative day 1 was associated with a -12.4% (99.5% CI, -15.2 to -9.4%) change in opioid utilization. In comparison, a stronger reduction was seen in those receiving more than 1 oral acetaminophen dose: -22.6% (99.5% CI, -26.2 to -18.9%). Unadjusted group medians were 550 and 490 oral morphine equivalents, respectively. Intravenous versus oral differences were less pronounced among those receiving more than 1 acetaminophen dose on the day of surgery: -8.0% (99.5% CI, -11.0 to -4.9%) median 499 oral morphine equivalents versus -8.7% (99.5% CI, -14.4 to -2.7%) median 445 oral morphine equivalents, respectively; all statistically significant, but none clinically significant. Comparable outcome patterns existed for opioid-related adverse effects. CONCLUSIONS: The demonstrated marginal effects do not support routine use of intravenous acetaminophen given alternative nonopioid analgesic options.

The Disease Protein Tulp1 Is Essential for Periactive Zone Endocytosis in Photoreceptor Ribbon Synapses.

Mutations in the Tulp1 gene cause severe, early-onset retinitis pigmentosa (RP14) in humans. In the retina, Tulp1 is mainly expressed in photoreceptors that use ribbon synapses to communicate with the inner retina. In the present study, we demonstrate that Tulp1 is highly enriched in the periactive zone of photoreceptor presynaptic terminals where Tulp1 colocalizes with major endocytic proteins close to the synaptic ribbon. Analyses of Tulp1 knock-out mice demonstrate that Tulp1 is essential to keep endocytic proteins enriched at the periactive zone and to maintain high levels of endocytic activity close to the synaptic ribbon. Moreover, we have discovered a novel interaction between Tulp1 and the synaptic ribbon protein RIBEYE, which is important to maintain synaptic ribbon integrity. The current findings suggest a new model for Tulp1-mediated localization of the endocytic machinery at the periactive zone of ribbon synapses and offer a new rationale and mechanism for vision loss associated with genetic defects in Tulp1.

Viral-mediated vision rescue of a novel AIPL1 cone-rod dystrophy model.

Defects in aryl hydrocarbon receptor interacting protein-like1 (AIPL1) are associated with blinding diseases with a wide range of severity in humans. We examined the mechanism behind autosomal dominant cone-rod dystrophy (adCORD) caused by 12 base pair (bp) deletion at proline 351 of hAIPL1 (P351Δ12) mutation in the primate-specific region of human AIPL1. Mutant P351Δ12 human isoform, aryl hydrocarbon receptor interacting protein-like 1 (hAIPL1) mice demonstrated a CORD phenotype with early defects in cone-mediated vision and subsequent photoreceptor degeneration. A dominant CORD phenotype was observed in double transgenic animals expressing both mutant P351Δ12 and normal hAIPL1, but not with co-expression of P351Δ12 hAIPL1 and the mouse isoform, aryl hydrocarbon receptor interacting protein-like 1 (mAipl1). Despite a dominant effect of the mutation, we successfully rescued cone-mediated vision in P351Δ12 hAIPL1 mice following high over-expression of WT hAIPL1 by adeno-associated virus-mediated gene delivery, which was stable up to 6 months after treatment. Our transgenic P351Δ12 hAIPL1 mouse offers a novel model of AIPL1-CORD, with distinct defects from both the Aipl1-null mouse mimicking LCA and the Aipl1-hypomorphic mice mimicking a slow progressing RP.

Serious gaming for orthotopic liver transplant anesthesiology: A randomized control trial.

Anesthetic management of orthotopic liver transplantation (OLT) is complex. Given the unequal distributions of liver transplant surgeries performed at different centers, anesthesiology providers receive relatively uneven OLT training and exposure. One well-suited modality for OLT training is the "serious game," an interactive application created for the purpose of imparting knowledge or skills, while leveraging the self-motivating elements of video games. We therefore developed a serious game designed to teach best practices for the anesthetic management of a standard OLT and determined if the game would improve resident performance in a simulated OLT. Forty-four residents on the liver transplant rotation were randomized to either the gaming group (GG) or the control group (CG) prior to their introductory simulation. Both groups were given access to the same educational materials and literature during their rotation, but the GG also had access to the OLT Trainer. Performance on the simulations were recorded on a standardized grading rubric. Both groups experienced an increase in score relative to baseline that was statistically significant at every stage. The improvements in scores were greater for the GG participants than the CG participants. Overall score improvement between the GG and CG (mean [standard deviation]) was statistically significant (GG, 7.95 [3.65]; CG, 4.8 [4.48]; P = 0.02), as were scores for preoperative assessment (GG, 2.67 [2.09]; CG, 1.17 [1.43]; P = 0.01) and anhepatic phase (GG, 1.62 [1.01]; CG, 0.75 [1.28]; P = 0.02). Of the residents with game access, 81% were "very satisfied" or "satisfied" with the game overall. In conclusion, adding a serious game to an existing educational curriculum for liver transplant anesthesia resulted in significant learning gains for rotating anesthesia residents. The intervention was straightforward to implement and cost-effective. Liver Transplantation 23 430-439 2017 AASLD.

Effects of Weight Loss with and without Exercise on Regional Body Fat Distribution in Postmenopausal Women.

BACKGROUND/AIMS: The purpose was to determine whether lifestyle interventions have different effects on regional fat in women with normal glucose tolerance vs. impaired glucose tolerance (NGT vs. IGT). METHODS: Changes in glucose metabolism (2-h oral glucose-tolerance tests), android to gynoid fat mass ratio (dual energy X-ray absorptiometry [DXA]), visceral to subcutaneous abdominal fat area ratio (CT), and abdominal to gluteal subcutaneous fat cell weight (FCW; adipose tissue biopsies) were determined in 60 overweight postmenopausal women (45-80 years) following 6 months of weight loss alone (WL; n = 28) or with aerobic exercise (AEX + WL; n = 32). RESULTS: The interventions led to ∼8% decrease in weight, but only the AEX + WL group improved fitness (↑11% in VO2max) and reduced the android-to-gynoid fat mass ratio (↓5%; p < 0.05). Both NGT and IGT groups reduced visceral and subcutaneous abdominal fat areas and abdominal and gluteal FCWs, which related to improvements in homeostatic model assessment (r = 0.34-0.42) and 2-h glucose (r = 0.34-0.35), respectively (p < 0.05). The decline in FCW was 2× greater in women with IGT following WL (p < 0.05). The ratios of abdominal-to-gluteal FCW did not change following either intervention. CONCLUSIONS: The mechanisms by which WL with and without exercise impact regional fat loss should be explored as reductions in abdominal fat area and subcutaneous FCW appear to influence glucose metabolism. This is a work of the U.S. Government and is not subject to copyright protection in the United States. Foreign copyrights may apply. Published by S. Karger AG, Basel.