Digital Commons Network^™

Potential Scenarios And Hazards In The Work Of The Future: A Systematic Review Of The Peer-Reviewed And Gray Literatures, Paul A Schulte, Jessica M K Streit, Fatima Sheriff, George Delclos, Sarah A Felknor, Sara L Tamers, Sherry Fendinger, James Grosch, Robert Sala

Faculty, Staff and Student Publications

It would be useful for researchers, practitioners, and decision-makers to anticipate the hazards that workers will face in the future. The focus of this study is a systematic review of published information to identify and characterize scenarios and hazards in the future of work. Eleven bibliographic databases were systematically searched for papers and reports published from 1999 to 2019 that described future of work scenarios or identified future work-related hazards. to compile a comprehensive collection of views of the future, supplemental and ad hoc searches were also performed. After screening all search records against a set of predetermined criteria, the …

Risk Prediction Rule For Advanced Neoplasia On Screening Colonoscopy For Average-Risk Individuals, Ala I Sharara, Ali El Mokahal, Ali H Harb, Natalia Khalaf, Fayez S Sarkis, Mustapha M El-Halabi, Nabil M Mansour, Ahmad Malli, Robert Habib

Faculty, Staff and Students Publications

BACKGROUND: In resource-limited countries, risk stratification can be used to optimize colorectal cancer screening. Few prospective risk prediction models exist for advanced neoplasia (AN) in true average-risk individuals.

AIM: To create and internally validate a risk prediction model for detection of AN in average-risk individuals.

METHODS: Prospective study of asymptomatic individuals undergoing first screening colonoscopy. Detailed characteristics including diet, exercise and medications were collected. Multivariate logistic regression was used to elucidate risk factors for AN (adenoma ≥1 cm, villous histology, high-grade dysplasia or carcinoma). The model was validated through bootstrapping, and discrimination and calibration of the model were assessed.

RESULTS: …

Predoctoral Periodontal Education And Covid-19: Challenges, Actions, And Learned Lessons, Karo Parsegian, Srinivas Ayilavarapu, Amity L Gardner, Nikola Angelov

Faculty, Staff and Student Publications

No abstract provided.

The Central Melanocortin System And Human Obesity, Yongjie Yang, Yong Xu

Children’s Nutrition Research Center Staff Publications

The prevalence of obesity and the associated comorbidities highlight the importance of understanding the regulation of energy homeostasis. The central melanocortin system plays a critical role in controlling body weight balance. Melanocortin neurons sense and integrate the neuronal and hormonal signals, and then send regulatory projections, releasing anorexigenic or orexigenic melanocortin neuropeptides, to downstream neurons to regulate the food intake and energy expenditure. This review summarizes the latest progress in our understanding of the role of the melanocortin pathway in energy homeostasis. We also review the advances in the identification of human genetic variants that cause obesity via mechanisms that …

Evidence For Craniofacial Enhancer Variation Underlying Nonsyndromic Cleft Lip And Palate, Vershanna E Morris, S Shahrukh Hashmi, Lisha Zhu, Lorena Maili, Christian Urbina, Steven Blackwell, Matthew R Greives, Edward P Buchanan, John B Mulliken, Susan H Blanton, W Jim Zheng, Jacqueline T Hecht, Ariadne Letra

Faculty, Staff and Student Publications

Nonsyndromic cleft lip with or without cleft palate (NSCLP) is a common birth defect for which only ~ 20% of the underlying genetic variation has been identified. Variants in noncoding regions have been increasingly suggested to contribute to the missing heritability. In this study, we investigated whether variation in craniofacial enhancers contributes to NSCLP. Candidate enhancers were identified using VISTA Enhancer Browser and previous publications. Prioritization was based on patterning defects in knockout mice, deletion/duplication of craniofacial genes in animal models and results of whole exome/whole genome sequencing studies. This resulted in 20 craniofacial enhancers to be investigated. Custom amplicon-based …

Canakinumab To Reduce Deterioration Of Cardiac And Respiratory Function In Sars-Cov-2 Associated Myocardial Injury With Heightened Inflammation (Canakinumab In Covid-19 Cardiac Injury: The Three C Study), Calvin C Sheng, Debasis Sahoo, Siddharth Dugar, Robier Aguillon Prada, Tom Kai Ming Wang, Ossama K Abou Hassan, Danielle Brennan, Daniel A Culver, Prabalini Rajendram, Abhijit Duggal, A Michael Lincoff, Steven E Nissen, Venu Menon, Paul C Cremer

Faculty, Staff and Student Publications

BACKGROUND: In patients with Covid-19, myocardial injury and increased inflammation are associated with morbidity and mortality. We designed a proof-of-concept randomized controlled trial to evaluate whether treatment with canakinumab prevents progressive respiratory failure and worsening cardiac dysfunction in patients with SARS-CoV2 infection, myocardial injury, and high levels of inflammation.

HYPOTHESIS: The primary hypothesis is that canakiumab will shorten time to recovery.

METHODS: The three C study (canakinumab in Covid-19 Cardiac Injury, NCT04365153) is a double-blind, randomized controlled trial comparing canakinumab 300 mg IV, 600 mg IV, or placebo in a 1:1:1 ratio in hospitalized Covid-19 patients with elevations in troponin …

Yebc Regulates Variable Surface Antigen Vlse Expression And Is Required For Host Immune Evasion In Borrelia Burgdorferi, Yan Zhang, Tong Chen, Sajith Raghunandanan, Xuwu Xiang, Jing Yang, Qiang Liu, Diane G Edmondson, Steven J Norris, X Frank Yang, Yongliang Lou

Faculty, Staff and Student Publications

Borrelia burgdorferi, the Lyme disease pathogen causes persistent infection by evading the host immune response. Differential expression of the surface-exposed lipoprotein VlsE that undergoes antigenic variation is a key immune evasion strategy employed by B. burgdorferi. Most studies focused on the mechanism of VlsE antigen variation, but little is known about VlsE regulation and factor(s) that regulates differential vlsE expression. In this study, we investigated BB0025, a putative YebC family transcriptional regulator (and hence designated BB0025 as YebC of B. burgdorferi herein). We constructed yebC mutant and complemented strain in an infectious strain of B. burgdorferi. The yebC mutant could …

Human Genes Differ By Their Uv Sensitivity Estimated Through Analysis Of Uv-Induced Silent Mutations In Melanoma, Ivan P Gorlov, Christopher I Amos, Spiridon Tsavachidis, Colin Begg, Eva Hernando, Chao Cheng, Ronglai Shen, Irene Orlow, Li Luo, Marc S Ernstoff, Joel Parker, Nancy E Thomas, Olga Y Gorlova, Marianne Berwick

Faculty, Staff and Students Publications

We hypothesized that human genes differ by their sensitivity to ultraviolet (UV) exposure. We used somatic mutations detected by genome-wide screens in melanoma and reported in the Catalog Of Somatic Mutations In Cancer. As a measure of UV sensitivity, we used the number of silent mutations generated by C>T transitions in pyrimidine dimers of a given transcript divided by the number of potential sites for this type of mutations in the transcript. We found that human genes varied by UV sensitivity by two orders of magnitude. We noted that the melanoma-associated tumor suppressor gene CDKN2A was among the top …

Low-Shot Deep Learning Of Diabetic Retinopathy With Potential Applications To Address Artificial Intelligence Bias In Retinal Diagnostics And Rare Ophthalmic Diseases, Philippe Burlina, William Paul, Philip Mathew, Neil Joshi, Katia D Pacheco, Neil M Bressler

Faculty, Staff and Students Publications

IMPORTANCE: Recent studies have demonstrated the successful application of artificial intelligence (AI) for automated retinal disease diagnostics but have not addressed a fundamental challenge for deep learning systems: the current need for large, criterion standard-annotated retinal data sets for training. Low-shot learning algorithms, aiming to learn from a relatively low number of training data, may be beneficial for clinical situations involving rare retinal diseases or when addressing potential bias resulting from data that may not adequately represent certain groups for training, such as individuals older than 85 years.

OBJECTIVE: To evaluate whether low-shot deep learning methods are beneficial when using …

Mir-30a Targets Gene Networks That Promote Browning Of Human And Mouse Adipocytes, Pradip K Saha, Mark P Hamilton, Kimal Rajapakshe, Vasanta Putluri, Jessica B Felix, Peter Masschelin, Aaron R Cox, Mandeep Bajaj, Nagireddy Putluri, Cristian Coarfa, Sean M Hartig

Faculty, Staff and Students Publications

MicroRNA-30a (miR-30a) impacts adipocyte function, and its expression in white adipose tissue (WAT) correlates with insulin sensitivity in obesity. Bioinformatic analysis demonstrates that miR-30a expression contributes to 2% of all miRNA expression in human tissues. However, molecular mechanisms of miR-30a function in fat cells remain unclear. Here, we expanded our understanding of how miR-30a expression contributes to antidiabetic peroxisome proliferator-activated receptor-γ (PPARγ) agonist activity and metabolic functions in adipocytes. We found that WAT isolated from diabetic patients shows reduced miR-30a levels and diminished expression of the canonical PPARγ target genes ADIPOQ and FABP4 relative to lean counterparts. In human adipocytes, …

Versatile Phenotype-Activated Cell Sorting, Jihwan Lee, Zhuohe Liu, Peter H Suzuki, John F Ahrens, Shujuan Lai, Xiaoyu Lu, Sihui Guan, François St-Pierre

Faculty, Staff and Students Publications

Unraveling the genetic and epigenetic determinants of phenotypes is critical for understanding and re-engineering biology and would benefit from improved methods to separate cells based on phenotypes. Here, we report SPOTlight, a versatile high-throughput technique to isolate individual yeast or human cells with unique spatiotemporal profiles from heterogeneous populations. SPOTlight relies on imaging visual phenotypes by microscopy, precise optical tagging of single target cells, and retrieval of tagged cells by fluorescence-activated cell sorting. To illustrate SPOTlight's ability to screen cells based on temporal properties, we chose to develop a photostable yellow fluorescent protein for extended imaging experiments. We screened 3 …

An Autism-Linked Missense Mutation In Shank3 Reveals The Modularity Of Shank3 Function, Li Wang, Kaifang Pang, Kihoon Han, Carolyn J Adamski, Wei Wang, Lingjie He, Jason K Lai, Vitaliy V Bondar, Joseph G Duman, Ronald Richman, Kimberley F Tolias, Patrick Barth, Timothy Palzkill, Zhandong Liu, J Lloyd Holder, Huda Y Zoghbi

Faculty, Staff and Students Publications

Genome sequencing has revealed an increasing number of genetic variations that are associated with neuropsychiatric disorders. Frequently, studies limit their focus to likely gene-disrupting mutations because they are relatively easy to interpret. Missense variants, instead, have often been undervalued. However, some missense variants can be informative for developing a more profound understanding of disease pathogenesis and ultimately targeted therapies. Here we present an example of this by studying a missense variant in a well-known autism spectrum disorder (ASD) causing gene SHANK3. We analyzed Shank3's in vivo phosphorylation profile and identified S685 as one phosphorylation site where one ASD-linked variant has …

Ampk Regulation Of Raptor And Tsc2 Mediate Metformin Effects On Transcriptional Control Of Anabolism And Inflammation, Jeanine L Van Nostrand, Kristina Hellberg, En-Ching Luo, Eric L Van Nostrand, Alina Dayn, Jingting Yu, Maxim N Shokhirev, Yelena Dayn, Gene W Yeo, Reuben J Shaw

Faculty, Staff and Students Publications

Despite being the frontline therapy for type 2 diabetes, the mechanisms of action of the biguanide drug metformin are still being discovered. In particular, the detailed molecular interplays between the AMPK and the mTORC1 pathway in the hepatic benefits of metformin are still ill defined. Metformin-dependent activation of AMPK classically inhibits mTORC1 via TSC/RHEB, but several lines of evidence suggest additional mechanisms at play in metformin inhibition of mTORC1. Here we investigated the role of direct AMPK-mediated serine phosphorylation of RAPTOR in a new

Estrogen/Progesterone Receptor And Her2 Discordance Between Primary Tumor And Brain Metastases In Breast Cancer And Its Effect On Treatment And Survival, Paul W Sperduto, Shane Mesko, Jing Li, Daniel Cagney, Ayal Aizer, Nancy U Lin, Eric Nesbit, Tim J Kruser, Jason Chan, Steve Braunstein, Jessica Lee, John P Kirkpatrick, Will Breen, Paul D Brown, Diana Shi, Helen A Shih, Hany Soliman, Arjun Sahgal, Ryan Shanley, William Sperduto, Emil Lou, Ashlyn Everett, Drexell Hunter Boggs, Laura Masucci, David Roberge, Jill Remick, Kristin Plichta, John M Buatti, Supriya Jain, Laurie E Gaspar, Cheng-Chia Wu, Tony J C Wang, John Bryant, Michael Chuong, James Yu, Veronica Chiang, Toshimichi Nakano, Hidefumi Aoyama, Minesh P Mehta

Faculty, Staff and Student Publications

BACKGROUND: Breast cancer treatment is based on estrogen receptors (ERs), progesterone receptors (PRs), and human epidermal growth factor receptor 2 (HER2). At the time of metastasis, receptor status can be discordant from that at initial diagnosis. The purpose of this study was to determine the incidence of discordance and its effect on survival and subsequent treatment in patients with breast cancer brain metastases (BCBM).

METHODS: A retrospective database of 316 patients who underwent craniotomy for BCBM between 2006 and 2017 was created. Discordance was considered present if the ER, PR, or HER2 status differed between the primary tumor and the …

When Patients Die: Patient Memorials And Group Reflection In An Internal Medicine Residency Program, Nicole Oakman, Jonathan Lim, Christine Bui, Holland Kaplan, Stephanie Sherman

Faculty, Staff and Students Publications

Patient death is a formative and emotional experience for physicians. Medical trainees are particularly susceptible to the emotional impact of patient death. However, few studies have examined how trainees process patient death. This study describes annual patient memorials organized at a large multisite academic graduate medical education program. Peer-led, 1-hour patient memorial services were organized for internal medicine residents, including large and small group reflection, a moment of silence, and collective art projects. At the conclusion of each memorial, participants completed a 10-question survey regarding their experience during the memorial and their prior experiences with patient death. Ninety-nine surveys were …

Clinical Efficacy Of Direct-Acting Antiviral Therapy For Recurrent Hepatitis C Virus Infection After Liver Transplantation In Patients With Hepatocellular Carcinoma, Mohamed Saleh Ismail, Manal Hassan, Saira Aijaz Khaderi, Wael Ahmed Yousry, Maha Mohsen Kamal El-Din, Mohamed Mohamed Bahaa El-Din, Osama Aboelfotoh El Sayed, Ahmed Omar Kaseb, John Alan Goss, Fasiha Kanwal, Prasun Kumar Jalal

Faculty, Staff and Students Publications

BACKGROUND: Recurrent hepatitis C virus (HCV) infection of transplanted liver allografts is universal in patients with detectable HCV viremia at the time of transplantation. Direct-acting antiviral (DAA) therapy has been adopted as the standard of care for recurrent HCV infection in the post-transplant setting. However, there are insufficient data regarding its efficacy in liver transplant (LT) recipients with a history of hepatocellular carcinoma (HCC), and the risk of HCC recurrence after DAA therapy is unknown.

AIM: To demonstrate predictors of DAA treatment failure and HCC recurrence in LT recipients.

METHODS: A total of 106 LT recipients given DAAs for recurrent …

Atrial Myocyte Nlrp3/Camkii Nexus Forms A Substrate For Postoperative Atrial Fibrillation, Jordi Heijman, Azinwi Phina Muna, Tina Veleva, Cristina E Molina, Henry Sutanto, Marcel Tekook, Qiongling Wang, Issam H Abu-Taha, Marcel Gorka, Stephan Künzel, Ali El-Armouche, Hermann Reichenspurner, Markus Kamler, Viacheslav Nikolaev, Ursula Ravens, Na Li, Stanley Nattel, Xander H T Wehrens, Dobromir Dobrev

Faculty, Staff and Students Publications

RATIONALE: Postoperative atrial fibrillation (POAF) is a common and troublesome complication of cardiac surgery. POAF is generally believed to occur when postoperative triggers act on a preexisting vulnerable substrate, but the underlying cellular and molecular mechanisms are largely unknown.

OBJECTIVE: To identify cellular POAF mechanisms in right atrial samples from patients without a history of atrial fibrillation undergoing open-heart surgery.

METHODS AND RESULTS: Multicellular action potentials, membrane ion-currents (perforated patch-clamp), or simultaneous membrane-current (ruptured patch-clamp) and [Ca

CONCLUSIONS: Preexisting Ca

Loss Of Speg Inhibitory Phosphorylation Of Ryanodine Receptor Type-2 Promotes Atrial Fibrillation, Hannah M Campbell, Ann P Quick, Issam Abu-Taha, David Y Chiang, Carlos F Kramm, Tarah A Word, Sören Brandenburg, Mohit Hulsurkar, Katherina M Alsina, Hui-Bin Liu, Brian Martin, Dennis Uhlenkamp, Oliver M Moore, Satadru K Lahiri, Eleonora Corradini, Markus Kamler, Albert J R Heck, Stephan E Lehnart, Dobromir Dobrev, Xander H T Wehrens

Faculty, Staff and Students Publications

BACKGROUND: Enhanced diastolic calcium (Ca

METHODS: Western blotting was performed with right atrial biopsies from patients with paroxysmal AF. SPEG atrial knockout mice were generated using adeno-associated virus 9. In mice, AF inducibility was determined using intracardiac programmed electric stimulation, and diastolic Ca

RESULTS: Western blotting revealed decreased SPEG protein levels in atrial biopsies from patients with paroxysmal AF in comparison with patients in sinus rhythm. SPEG atrial-specific knockout mice exhibited increased susceptibility to pacing-induced AF by programmed electric stimulation and enhanced Ca

CONCLUSIONS: Unlike other kinases (PKA, CaMKII) that increase RyR2 activity, SPEG phosphorylation reduces RyR2-mediated sarcoplasmic reticulum Ca

In Vitro Susceptibility Of Treponema Pallidum Subsp Pallidum To Doxycycline, Diane G Edmondson, Gary P Wormser, Steven J Norris

Faculty, Staff and Student Publications

Doxycycline is regarded as an effective therapy for early syphilis, and there is increasing interest in using doxycycline for prophylaxis of this infection. However, the MIC of doxycycline for Treponema pallidum subsp. pallidum has not been reported previously. In this study, an in vitro culture system was utilized to determine that the MIC of doxycycline is 0.06 to 0.10 μg/ml for four strains of T. pallidum subsp. pallidum (Nichols, SS14, UW231B, and UW249B). The Nichols strain cultured in vitro with doxycycline was also tested for infectivity in rabbits, and the minimum bactericidal concentration (MBC) was found to be ≤0.1 μg/ml …

Structural Characterization Of A Clinically Described Heparin-Like Substance In Plasma Causing Bleeding, Yanlei Yu, Karen Bruzdoski, Vadim Kostousov, Lisa Hensch, Shiu-Ki Hui, Fakiha Siddiqui, Amber Farooqui, Ahmed Kouta, Fuming Zhang, Jawed Fareed, Jun Teruya, Robert J Linhardt

Faculty, Staff and Students Publications

Heparin-like substances (HLS) have been described in various clinical situations, including in settings of liver disease associated with infection, transplant, and metastasis. HLS are generally attributed to circulating glycosaminoglycans. Initial results for this patient showed coagulopathy due to liver disease without HLS. Two weeks after liver transplantation, a 10 year-old female with liver failure patient began to bleed from catheter insertion sites, mouth, and nares and HLS was suspected. The patient subsequently died and these clinical samples resulted in the isolation of a single heparan sulfate (HS) present at high concentrations in the plasma. Analysis of this HS showed it …

Structural Insights Of Transcriptionally Active, Full-Length Androgen Receptor Coactivator Complexes, Xinzhe Yu, Ping Yi, Ross A Hamilton, Hong Shen, Muyuan Chen, Charles E Foulds, Michael A Mancini, Steven J Ludtke, Zhao Wang, Bert W O'Malley

Faculty, Staff and Students Publications

Steroid receptors activate gene transcription by recruiting coactivators to initiate transcription of their target genes. For most nuclear receptors, the ligand-dependent activation function domain-2 (AF-2) is a primary contributor to the nuclear receptor (NR) transcriptional activity. In contrast to other steroid receptors, such as ERα, the activation function of androgen receptor (AR) is largely dependent on its ligand-independent AF-1 located in its N-terminal domain (NTD). It remains unclear why AR utilizes a different AF domain from other receptors despite that NRs share similar domain organizations. Here, we present cryoelectron microscopy (cryo-EM) structures of DNA-bound full-length AR and its complex structure …

Guidance For Contemporary Use Of Biologics In Management Of Chronic Rhinosinusitis With Nasal Polyps: Discussion From A National Institutes Of Health-Sponsored Workshop, Lauren T Roland, Timothy L Smith, Rodney J Schlosser, Zachary M Soler, Anju T Peters, Tanya M Laidlaw, Benjamin S Bleier, Vijay Ramakrishnan, Elina Toskala, David W Kennedy, Amber U Luong

Faculty, Staff and Student Publications

BACKGROUND: Biologic medications are emerging as options for treating chronic rhinosinusitis with nasal polyps (CRSwNP). Several questions remain regarding patient selection, indications, clinical efficacy, and cost effectiveness.

METHODS: In November 2019, a group of physicians and scientists gathered to consider strategies for future studies regarding biologics. During the discussion, gaps in knowledge highlighted a need for a consensus on the present day use of biologics in polyp patients.

RESULTS: The goal of this guideline is to propose recommendations for the current use of biologics in CRSwNP as new evidence continues to emerge and inform practice.

CONCLUSION: We suggest that physicians …

Long Noncoding Rna H19x Is A Key Mediator Of Tgf-Β-Driven Fibrosi, Elena Pachera, Shervin Assassi, Gloria A Salazar, Mara Stellato, Florian Renoux, Adam Wunderlin, Przemyslaw Blyszczuk, Robert Lafyatis, Fina Kurreeman, Jeska De Vries-Bouwstra, Tobias Messemaker, Carol A Feghali-Bostwick, Gerhard Rogler, Wouter T Van Haaften, Gerard Dijkstra, Fiona Oakley, Maurizio Calcagni, Janine Schniering, Britta Maurer, Jörg Hw Distler, Gabriela Kania, Mojca Frank-Bertoncelj, Oliver Distler

Faculty, Staff and Student Publications

TGF-β is a master regulator of fibrosis, driving the differentiation of fibroblasts into apoptosis-resistant myofibroblasts and sustaining the production of extracellular matrix (ECM) components. Here, we identified the nuclear long noncoding RNA (lncRNA) H19X as a master regulator of TGF-β-driven tissue fibrosis. H19X was consistently upregulated in a wide variety of human fibrotic tissues and diseases and was strongly induced by TGF-β, particularly in fibroblasts and fibroblast-related cells. Functional experiments following H19X silencing revealed that H19X was an obligatory factor for TGF-β-induced ECM synthesis as well as differentiation and survival of ECM-producing myofibroblasts. We showed that H19X regulates DDIT4L gene …

Yttrium-90 Selective Internal Radiotherapy As Bridge To Curative Hepatectomy For Recurrent Malignant Solid Pseudopapillary Neoplasm Of Pancreas: Case Report And Review Of Literature, Adam R Dyas, David Thor Johnson, Erin Rubin, Richard D Schulick, Piyush Kumar Sharma

Faculty, Staff and Student Publications

Recurrent malignant solid pseudopapillary neoplasms of the pancreas (SPNP) are rare tumors with unpredictable clinical and histopathological features. There is a lack of consensus regarding utilization of adjuvant modalities in conjunction with or in lieu of curative metastatectomy. We present a remarkable case where Yttrium-90 selective internal radiation therapy (Y-90 SIRT) was successfully utilized to elucidate underlying tumor biology and aid resection of a large multifocal recurrent metastatic SPNP in the right hemi-liver of a 59-year-old female. Thus, in cases where curative metastatectomy remains the treatment goal in management of recurrent and/or metastatic SPNPs, Y-90 SIRT is a safe and …

Loss Of Uncoupling Protein 3 Attenuates Western Diet-Induced Obesity, Systemic Inflammation, And Insulin Resistance In Rats, Tyler M Lomax, Sadia Ashraf, Gizem Yilmaz, Romain Harmancey

Faculty, Staff and Student Publications

OBJECTIVE: Uncoupling protein 3 (UCP3) is a mitochondrial carrier related to fatty acid metabolism. Although gene variants of UCP3 are associated with human obesity, their contribution to increased adiposity remains unclear. This study investigated the impact that loss of UCP3 has on diet-induced obesity in rats.

METHODS: Male UCP3 knockout rats (ucp3

RESULTS: Loss of UCP3 decreased fat mass gain, white adipocytes size, and systemic inflammation. The ucp3

CONCLUSIONS: Loss of UCP3 partially protects rats from diet-induced obesity. This phenotype is related to induction of a compensatory antioxidant mechanism and prevention of iBAT whitening.

Mtor-Initiated Metabolic Switch And Degeneration In The Retinal Pigment Epithelium, Young-Mi Go, Jing Zhang, Jolyn Fernandes, Christopher Litwin, Rui Chen, Theodore G Wensel, Dean P Jones, Jiyang Cai, Yan Chen

Faculty, Staff and Students Publications

The retinal pigment epithelium (RPE) is a particularly vulnerable tissue to age-dependent degeneration. Over the life span, the RPE develops an expanded endo-lysosomal compartment to maintain the high efficiency of phagocytosis and degradation of photoreceptor outer segments (POS) necessary for photoreceptor survival. As the assembly and activation of the mechanistic target of rapamycin complex 1 (mTORC1) occur on the lysosome surface, increased lysosome mass with aging leads to higher mTORC1 activity. The functional consequences of hyperactive mTORC1 in the RPE are unclear. In the current study, we used integrated high-resolution metabolomic and genomic approaches to examine mice with RPE-specific deletion …

Characterization Of Retinal Biomechanical Properties Using Brillouin Microscopy, Yogeshwari S Ambekar, Manmohan Singh, Giuliano Scarcelli, Elda M Rueda, Benjamin M Hall, Ross A Poché, Kirill V Larin

Faculty, Staff and Students Publications

SIGNIFICANCE: The retina is critical for vision, and several diseases may alter its biomechanical properties. However, assessing the biomechanical properties of the retina nondestructively is a challenge due to its fragile nature and location within the eye globe. Advancements in Brillouin spectroscopy have provided the means for nondestructive investigations of retina biomechanical properties.

AIM: We assessed the biomechanical properties of mouse retinas using Brillouin microscopy noninvasively and showed the potential of Brillouin microscopy to differentiate the type and layers of retinas based on stiffness.

APPROACH: We used Brillouin microscopy to quantify stiffness of fresh and paraformaldehyde (PFA)-fixed retinas. As further …

Improvement Of Cryo-Em Maps By Density Modification, Thomas C Terwilliger, Steven J Ludtke, Randy J Read, Paul D Adams, Pavel V Afonine

Faculty, Staff and Students Publications

A density-modification procedure for improving maps from single-particle electron cryogenic microscopy (cryo-EM) is presented. The theoretical basis of the method is identical to that of maximum-likelihood density modification, previously used to improve maps from macromolecular X-ray crystallography. Key differences from applications in crystallography are that the errors in Fourier coefficients are largely in the phases in crystallography but in both phases and amplitudes in cryo-EM, and that half-maps with independent errors are available in cryo-EM. These differences lead to a distinct approach for combination of information from starting maps with information obtained in the density-modification process. The density-modification procedure was …

Structure And Mechanism Of A Unique Diiron Center In Mammalian Stearoyl-Coa Desaturase, Jiemin Shen, Gang Wu, Ah-Lim Tsai, Ming Zhou

Faculty, Staff and Students Publications

Stearoyl-CoA desaturase 1 (SCD1) is a membrane-embedded metalloenzyme that catalyzes formation of a double-bond on a saturated acyl-CoA. SCD1 has a diiron center and its proper function requires an electron transport chain composed of NADH (or NADPH), cytochrome b5 reductase (b5R), and cytochrome b5 (cyt b5). Since SCD1 is a key regulator in fat metabolism and is required for survival of cancer cells, there is intense interest in targeting SCD1 for various metabolic diseases and cancers. Crystal structures of human and mouse SCD1 were reported recently, however, both proteins have two zinc ions instead of two iron ions in the …

The Ubiquitin Ligase Cullin-1 Associates With Chromatin And Regulates Transcription Of Specific C-Myc Target Genes, Melanie A Sweeney, Polina Iakova, Laure Maneix, Fu-Yuan Shih, Hannah E Cho, Ergun Sahin, Andre Catic

Faculty, Staff and Students Publications

Transcription is regulated through a dynamic interplay of DNA-associated proteins, and the composition of gene-regulatory complexes is subject to continuous adjustments. Protein alterations include post-translational modifications and elimination of individual polypeptides. Spatially and temporally controlled protein removal is, therefore, essential for gene regulation and accounts for the short half-life of many transcription factors. The ubiquitin-proteasome system is responsible for site- and target-specific ubiquitination and protein degradation. Specificity of ubiquitination is conferred by ubiquitin ligases. Cullin-RING complexes, the largest family of ligases, require multi-unit assembly around one of seven cullin proteins. To investigate the direct role of cullins in ubiquitination of …