Faculty Bibliography

Autophagy-lysosome pathway (ALP) disruption is considered pathogenic in multiple neurodegenerative diseases; however, current methods are inadequate to investigate macroautophagy/autophagy flux in brain in vivo and its therapeutic modulation. Here, we describe a novel autophagy reporter mouse (TRGL6) stably expressing a dual-fluorescence-tagged LC3 (tfLC3, mRFP-eGFP-LC3) by transgenesis selectively in neurons. The tfLC3 probe distributes widely in the central nervous system, including spinal cord. Expression levels were similar to endogenous LC3 and induced no detectable ALP changes. This ratiometric reporter registers differential pH-dependent changes in color as autophagosomes form, fuse with lysosomes, acidify, and degrade substrates within autolysosomes. We confirmed predicted changes in neuronal autophagy flux following specific experimental ALP perturbations. Furthermore, using a third fluorescence label in TRGL6 brains to identify lysosomes by immunocytochemistry, we validated a novel procedure to detect defective autolysosomal acidification in vivo. Thus, TRGL6 mice represent a unique tool to investigate in vivo ALP dynamics in specific neuron populations in relation to neurological diseases, aging, and disease modifying agents. Abbreviations: ACTB: actin, beta; AD: Alzheimer disease; AL: autolysosomes; ALP: autophagy-lysosome pathway; AP: autophagosome; APP: amyloid beta (Abeta) precursor protein; ATG5: autophagy related 5; ATG7: autophagy related 7; AV: autophagic vacuoles; CNS: central nervous system; CTSD: cathepsin D; CQ: chloroquine; DMEM: Dulbecco's modified Eagle's medium; GFP: green fluorescent protein; GABARAP: gamma-aminobutyric acid receptor associated protein; GABARAPL2/GATE16: gamma-aminobutyric acid (GABA) receptor-associated protein-like 2; ICC: immunocytochemistry; ICV: intra-cerebroventricular; LAMP2: lysosomal-associated membrane protein 2; Leup: leupeptin; LY: lysosomes; MAP1LC3/LC3: microtubule-associated protein 1 light chain 3; MTOR: mechanistic target of rapamycin kinase; RBFOX3/NeuN: RNA binding protein, fox-1 homolog (C. elegans) 3; RFP: red fluorescent protein; RPS6KB1: ribosomal protein S6 kinase, polypeptide 1; SDS-PAGE: sodium dodecyl sulfate-polyacrylamide gel electrophoresis; SQSTM1: sequestosome 1; tfLC3: mRFP-eGFP-LC3; TRGL6: Thy1 mRFP eGFP LC3-line 6; PCR: polymerase chain reaction; PD: Parkinson disease.

The Japan Obstetric Compensation System for Cerebral Palsy (JOCS-CP), which investigates, develops preventive mechanisms and awards monetary compensation, to cases of cerebral palsy was urgently introduced in 2009 in response to growing concern about Japan's deteriorating perinatal care and low birthrate. Under the political leadership, the Japan Council for Quality Health Care launched the JOCS-CP with support of various stakeholders. The JOCS-CP features of no-fault-based compensation which was discussed decades ago in the Japan Medical Association aiming at financial aid to patient and family and early settlement of dispute. As of 2017, 2233 petitions had been approved by the Review Committee for compensation. All the approved cases were consecutively put on analysis in the Investigation Committee which has compiled more than 1000 Investigative Reports. The reports were delivered not only to the childbirth facility but to the guardians/families. Survey revealed that most of childbirth facility and the guardians/families responded in favor of the reports. With regard to amelioration of profound cerebral palsy, the Prevention Report has been published on annual basis through analysis of all the Investigative Reports. The Prevention Reports and other educational materials were produced and distributed not only among medical professionals but among pregnant women. It is notable that the number of lawsuit filing related to obstetrics demonstrated rapid decrease compared to that of other medical specialties. The JOCS-CP could be described as a social experiment. It was overhauled in 2015 but deserves further discussion on reform for evolving into better system.

Background: Mutations in plakophilin-2 (PKP2) are the most common cause of familial Arrhythmogenic Right Ventricular Cardiomyopathy, a disease characterized by ventricular arrhythmias, sudden death and progressive fibrofatty cardiomyopathy. The relation between loss of PKP2 expression and structural cardiomyopathy remains under study, though paracrine activation of pro-fibrotic intracellular signaling cascades is a likely event. Previous studies have indicated that ATP release into the intracellular space, and activation of adenosine receptors, can regulate fibrosis in various tissues. However, the role of this mechanism in the heart, and in the specific case of a PKP2-initiated cardiomyopathy, remains unexplored. The aim of this study was to investigate the role of ATP/adenosine in the progression of a PKP2-associated cardiomyopathy.
Methods and Results: HL1 cells were used to study PKP2- and Connexin43 (Cx43)-dependent ATP release. HL1 cells silenced for PKP2 showed increased ATP release compared to control. Knockout of Cx43 in the same cells blunted the effect. A cardiac-specific, tamoxifenactivated PKP2 knock-out murine model (PKP2-cKO) was used to define the effect of adenosine receptor blockade on the progression of a PKP2-dependent cardiomyopathy. Transcriptomic data of PKP2-cKO mice revealed overexpression of genes involved in adenosine-receptor cascades. Treatment with Istradefylline (an adenosine 2A receptorblocker) tempered the progression of fibrosis and mechanical failure observed in PKP2-cKO mice (see Fig. B,C). In contrast, PSB115, a blocker of the 2B adenosine receptor, showed opposite effects.
Conclusion(s): Paracrine adenosine 2A receptor activation contributes to the progression of fibrosis and impaired cardiac function in animals deficient in PKP2. Given the limitations of the animal model, translation to the case of patients with PKP2 deficiency needs to be done with caution. (Figure Presented)

Radiotherapy can be synergistically combined with immunotherapy in mouse models, extending its efficacious effects outside of the irradiated field (abscopal effects). We previously reported that a regimen encompassing local radiotherapy in combination with anti-CD137 plus anti-PD-1 mAbs achieves potent abscopal effects against syngeneic transplanted murine tumors up to a certain tumor size. Knowing that TGF-beta expression or activation increases in irradiated tissues, we tested whether TGF-beta blockade may further enhance abscopal effects in conjunction with the anti-PD-1 plus anti-CD137 mAb combination. Indeed, TGFβ blockade with 1D11, a TGFβ neutralizing monoclonal antibody, markedly enhanced abscopal effects and overall treatment efficacy against subcutaneous tumors of either 4T1 breast cancer cells or large MC38 colorectal tumors. Increases in CD8 T cells infiltrating the non-irradiated lesion were documented upon combined treatment, which intensely expressed Granzyme-B as an indicator of cytotoxic effector capability. Interestingly, tumor tissue but not healthy tissue irradiation results in the presence of higher concentrations of TGFβ in the non-irradiated contralateral tumor which showed smad2/3 phosphorylation increases in infiltrating CD8 T cells. In conclusion, radiotherapy-induced TGF-beta hampers abscopal efficacy even upon combination with a potent immunotherapy regimen. Therefore TGF-beta blockade in combination with radioimmunotherapy results in greater efficacy.

Background: The occurrence of bifid mandibular canals is unusual but not rare. Previous reviews and case studies have described numerous types of bifid canals based on location, anatomy, and contents. Developmentally, ossification of the mandible begins at the region of the mental foramen and continues posteriorly, forming the mandibular canal around the neurovascular bundle within. This process explains the creation of multiple mandibular canals and the diversity of canal types previously recorded in the literature. However, the presence of two distinct mandibular canals, each originating from its own mandibular foramen, is even more unusual. Material(s) and Method(s): This case report describes a unilateral variant discovered during the dissection of a 92-year-old African American female. Result(s): On the left side, the cadaver presents two distinct mandibular canals, each containing a branch of the inferior alveolar artery and mandibular nerve, the third division of the trigeminal. The nerves within the two canals were distinct from each other at the level of the posterior division of the mandibular nerve, within 1 cm of foramen ovale. Conclusion(s): This is the first description of such an occurrence and emphasizes the need for identification of the contents of a bifid or accessory mandibular canal prior to invasive procedures.

Cyanotic heart lesions are a complex subset of congenital heart disease (CHD) in which patients are desaturated until surgical repair or palliation. We hypothesized that a direct relationship would exist between degree of desaturation and presence of systemic inflammation and brain injury in unrepaired patients less than 1 year of age. The pre-operative desaturation with augmented systemic inflammation would predict a more complex post-operative course. Fifty patients with CHD were enrolled in this study and classified as cyanotic (O₂ ≤ 90%) or acyanotic (O₂ > 90%) based on SpO₂. Serum inflammatory mediators measured included interleukins (IL)-6, IL-8, IL-12p70, IL-10, IL-1β, tumor necrosis factor (TNF)-α, interferon (INF)-γ; macrophage inhibitory factor (MIF) and a novel brain biomarker, phosphorylated neurofilament heavy subunit (pNF-H). Twenty-two cyanotic and 28 acyanotic subjects were enrolled with SpO₂ of 78 ± 18% and 98 ± 2% (p < 0.001), respectively, and mean age of 72 days (range 2-303) and 102 days (range 1-274), respectively. Cyanotic vs acyanotic subjects had elevated serum IL-6 (6.6 ± 7.6 vs 2.9 ± 2.9 pg/ml, p = 0.019) and pNF-H (222 ± 637 vs 57 ± 121 pg/ml, p = 0.046), and both biomarkers correlated with degree of desaturation (Spearman rank-order correlation ρ = - 0.30, p = 0.037 and ρ = - 0.29 p = 0.049, respectively). Post-operative inotrope scores at 24 h and duration of mechanical ventilation correlated inversely with pre-operative oxygen saturation (ρ = - 0.380, p = 0.014 and ρ = - 0.362, p = 0.020, respectively). The degree of pre-operative desaturation correlated with a more complicated post-operative course supporting the need for advanced peri-operative therapy in this population.

The next frontier of orthopedic implants are resorbable devices. Tissue engineering advances have created a demand for scaffolds that can facilitate biologic regeneration. Scaffolds that will degrade over time with the infiltration of host cells are of particular interest. Several principles have been identified as desirable design features for such scaffolds. Furthermore, the era of 3D printing has ushered new possibilities for scaffold production that brings this technology closer to market use. This article explores the future of the design and manufacture of resorbable scaffolds.

Advances in the understanding of the complexities of the Wnt signaling pathway during development and tissue homeostasis have made the Wnt pathway one of the prime candidates for translational applications during tissue regeneration. Wnts are key components of the stem cell niche and are short range signaling molecules responsible for cellular decisions such as proliferation and differentiation. Systemic treatment using biologics targeting the Wnt signaling pathway have shown promising early results and will likely enter the clinical arena in the near future. This comprehensive review summarizes the intricacies how Wnts function in the context of the bone regeneration.

Macrophages in the heart have dual roles in injury and repair after myocardial infarction, and understanding the two sides of this coin using traditional 'bulk cell' technologies has been challenging. By combining genetic fate-mapping and single-cell transcriptomics, a new study (Nat. Immunol. 2019;20:29-39) reveals how distinct macrophage populations expand and diverge across the healthy heart and after infarction.

PURPOSE/OBJECTIVE:Schools undergoing curricular reform are reconsidering the optimal timing of Step 1. This study provides a psychometric investigation of the impact on United States Medical Licensing Examination Step 1 scores of changing the timing of Step 1 from after completion of the basic science curricula to after core clerkships. METHOD/METHODS:Data from four schools that recently moved the examination were analyzed in a pre-post format using examinee scores from three years before and after the change. The sample included scores from 2008 through 2016. Several confounders were addressed, including rising national scores and potential differences in cohort abilities using deviation scores and analysis of covariance (ANCOVA) controlling for Medical College Admission Test (MCAT) scores. A resampling procedure compared study schools' score changes to similar schools' in the same time period. RESULTS:The ANCOVA indicated that post-change Step 1 scores were higher compared to pre-change (adjusted difference = 2.67, 95% confidence interval [CI]: 1.50-3.83, P < .001; effect size = 0.14) after adjusting for MCAT scores and rising national averages. The average score increase in the study schools was larger than changes seen in similar schools. Failure rates also decreased from 2.87% (n = 48) pre-change to 0.39% (n = 6) post-change (P < .001). CONCLUSIONS:Results suggest moving Step 1 after core clerkships yielded a small increase in scores and a reduction in failure rates. While these small increases are unlikely to represent meaningful knowledge gains, this demonstration of "non-inferiority" may allow schools to implement significant curricular reformsWritten work prepared by employees of the Federal Government as part of their official duties is, under the U.S. Copyright Act, a "work of the United States Government" for which copyright protection under Title 17 of the United States Code is not available. As such, copyright does not extend to the contributions of employees of the Federal Government.