Faculty Bibliography

Obesity is a top public health concern, and a molecule that safely treats obesity is urgently needed. Disulfiram (known commercially as Antabuse), an FDA-approved treatment for chronic alcohol addiction, exhibits anti-inflammatory properties and helps protect against certain types of cancer. Here, we show that in mice disulfiram treatment prevented body weight gain and abrogated the adverse impact of an obesogenic diet on insulin responsiveness while mitigating liver steatosis and pancreatic islet hypertrophy. Additionally, disulfiram treatment reversed established diet-induced obesity and metabolic dysfunctions in middle-aged mice. Reductions in feeding efficiency and increases in energy expenditure were associated with body weight regulation in response to long-term disulfiram treatment. Loss of fat tissue and an increase in liver fenestrations were also observed in rats on disulfiram. Given the potent anti-obesogenic effects in rodents, repurposing disulfiram in the clinic could represent a new strategy to treat obesity and its metabolic comorbidities.

In-situ hybridization (ISH) analysis is a highly desirable, versatile approach for assessing biomarker expression status in a spatial context. Most researchers rely on immunostaining (protein targets) or qPCR (mRNA). However, not all proteins can be immunolabeled due to a lack of well-validated antibodies. The qPCR approach, although highly specific, cannot provide spatial information. RNAscope employs a unique double Z probe that has to bind to the target RNA in tandem in order to be recognized by the preamplifiers and amplifiers. A fluorescent/chromogenic labeled probe then binds to the multiple binding sites of the amplifiers, which improves detection of low expressing RNA and reduces non-specific binding. RNAscope replaces cumbersome radioactive and chromogenic ISH with more hassle-free chromogen and fluorescence-labelled probes. At the NYULMC Experimental Pathology Core we have integrated RNAscope with Polaris multispectral imaging and quantitative analysis using different software platforms. About 21 laboratories have used this workflow to address their specific questions. We have also established and validated the newer BaseScopeTM assay. In contrast to RNAscope, which targets lncRNA and mRNA sequences greater than 300nt, BaseScopeTM enables detection of short RNA target sequences between 50-300nt. It can be used to detect exon junctions/splice variants, circular RNA, pre-miRNA, and point mutations. We adapted BaseScopeTM to co-detect circular RNA and its linear counterpart in a differentiating cell population, which could not be established on glass chamber slides and had to be stained on a plastic petri dish. In conclusion, RNAscope and BaseScopeTM RNA-ISH are powerful alternative strategies for assessing the spatial distribution of critical biomarkers within intact tissues and cells. This approach coupled with sophisticated imaging modalities and downstream analysis support provides new collaborative opportunities for Core aboratories.
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OBJECTIVES/OBJECTIVE:To examine one health system's response to the essential care of its hip fracture population during the COVID-19 pandemic and report on its effect on patient outcomes. DESIGN/METHODS:Prospective cohort study SETTING:: Seven musculoskeletal care centers with New York City and Long Island. PATIENTS/PARTICIPANTS/METHODS:138 recent and 115 historical hip fracture patients. INTERVENTION/METHODS:Patients with hip fractures occurring between February 1, 2020 and April 15, 2020 or between February 1, 2019 and April 15, 2019 were prospectively enrolled in an orthopedic trauma registry and chart reviewed for demographic and hospital quality measures. Patients with recent hip fractures were identified as COVID positive (C+), COVID suspected (Cs) or COVID negative (C-). MAIN OUTCOME MEASUREMENTS/METHODS:Hospital quality measures, inpatient complications and mortality rates. RESULTS:Seventeen (12.2%) patients were confirmed C+ by testing and another 14 (10.1%) were suspected (Cs) of having had the virus but were never tested. The C+ cohort, when compared to Cs and C- cohorts, had: an increased mortality rate (35.3% vs 7.1% vs 0.9%), increased length of hospital stay, a greater major complication rate and a greater incidence of ventilator need postoperatively. CONCLUSIONS:COVID-19 had a devastating effect on the care of hip fracture patients during the pandemic. Although practice patterns generally remained unchanged, treating physicians need to understand the increased morbidity and mortality in hip fracture patients complicated by COVID-19. LEVEL OF EVIDENCE/METHODS:Prognostic Level III. See Instructions for Authors for a complete description of Levels of Evidence.

The human GABA_B receptor-a member of the class C family of G-protein-coupled receptors (GPCRs)-mediates inhibitory neurotransmission and has been implicated in epilepsy, pain and addiction¹. A unique GPCR that is known to require heterodimerization for function^2-6, the GABA_B receptor has two subunits, GABA_B1 and GABA_B2, that are structurally homologous but perform distinct and complementary functions. GABA_B1 recognizes orthosteric ligands^7,8, while GABA_B2 couples with G proteins^9-14. Each subunit is characterized by an extracellular Venus flytrap (VFT) module, a descending peptide linker, a seven-helix transmembrane domain and a cytoplasmic tail¹⁵. Although the VFT heterodimer structure has been resolved¹⁶, the structure of the full-length receptor and its transmembrane signalling mechanism remain unknown. Here we present a near full-length structure of the GABA_B receptor at atomic resolution, captured in an inactive state by cryo-electron microscopy. Our structure reveals several ligands that preassociate with the receptor, including two large endogenous phospholipids that are embedded within the transmembrane domains to maintain receptor integrity and modulate receptor function. We also identify a previously unknown heterodimer interface between transmembrane helices 3 and 5 of both subunits, which serves as a signature of the inactive conformation. A unique 'intersubunit latch' within this transmembrane interface maintains the inactive state, and its disruption leads to constitutive receptor activity.

Chinese hamster ovary (CHO) cells are the most widely used mammalian hosts for recombinant protein production due to their hardiness, ease of transfection, and production of glycan structures similar to those in natural human monoclonal antibodies. To enhance the usefulness of CHO-K1 cells we developed a new selection system based on double auxotrophy. We used CRISPR-Cas9 to knockout the genes that encode the bifunctional enzymes catalyzing the last two steps in the de novo synthesis of pyrimidines and purines (uridine monophosphate synthase and 5-aminoimidazole-4-carboxamide ribonucleotide formyltransferase/IMP cyclohydrolase [ATIC], respectively). Survival of these doubly auxotrophic cells depends on the provision of sources of purines and pyrimidines or on the transfection and integration of open reading frames encoding these two enzymes. We successfully used one such double auxotroph (UA10) to select for stable transfectants carrying (a) the recombinant tumor necrosis factor-α receptor fusion protein etanercept and (b) the heavy and light chains of the anti-Her2 monoclonal antibody trastuzumab. Transfectant clones produced these recombinant proteins in a stable manner and in substantial amounts. The availability of this double auxotroph provides a rapid and efficient selection method for the serial or simultaneous transfer of genes for multiple polypeptides of choice into CHO cells using readily available purine- and pyrimidine-free commercial media.

The placenta provides nutritional and gas exchange between fetus and mother. Early in pregnancy, placental trophoblasts proliferate rapidly and invade aggressively. As pregnancy progresses, placental cells begin to age. Indeed, pregnancy itself has a tightly regulated duration, determined in large part by placental lifespan. Late in pregnancy, placental cells reach a senescent apoptotic state, activated by a number of intrinsic and extrinsic factors, including oxidative stress (OS), and DNA damage. Pregnancy complications, stillbirths and neonatal deaths have been related to OS and abnormal placental aging. Telomeres, the protective nucleoprotein structures at the ends of linear chromosomes, shorten both from cell replication and from exposure to OS. When telomeres become critically short they trigger cell cycle arrest and eventually cell death. Telomere attrition thus provide an intrinsic mechanism to explain tissue senescence and aging. Mounting evidence suggests that senescence of placental and fetal membrane cells results from telomere attrition. We review the studies that have addressed the role of telomere length (TL) in placentas from normal and complicated pregnancies, including pre-eclampsia, intrauterine growth restriction, gestational diabetes, and stillbirth. To date studies have uncovered associations between TL and a number of obstetrical complications. Future research is needed to determine whether these associations are causative, i.e. whether these clinical conditions result from telomere dysfunction, and whether particular features of telomeres, e.g. mean or shortest length, etc. could serve as clinically useful biomarkers of placental health.

BACKGROUND:The discovery that much of the non-protein-coding genome is transcribed and plays a diverse functional role in fundamental cellular processes has led to an explosion in the development of tools and technologies to investigate the role of these noncoding RNAs in cardiovascular health. Furthermore, identifying noncoding RNAs for targeted therapeutics to treat cardiovascular disease is an emerging area of research. The purpose of this statement is to review existing literature, offer guidance on tools and technologies currently available to study noncoding RNAs, and identify areas of unmet need. METHODS:The writing group used systematic literature reviews (including MEDLINE, Web of Science through 2018), expert opinion/statements, analyses of databases and computational tools/algorithms, and review of current clinical trials to provide a broad consensus on the current state of the art in noncoding RNA in cardiovascular disease. RESULTS:Significant progress has been made since the initial studies focusing on the role of miRNAs (microRNAs) in cardiovascular development and disease. Notably, recent progress on understanding the role of novel types of noncoding small RNAs such as snoRNAs (small nucleolar RNAs), tRNA (transfer RNA) fragments, and Y-RNAs in cellular processes has revealed a noncanonical function for many of these molecules. Similarly, the identification of long noncoding RNAs that appear to play an important role in cardiovascular disease processes, coupled with the development of tools to characterize their interacting partners, has led to significant mechanistic insight. Finally, recent work has characterized the unique role of extracellular RNAs in mediating intercellular communication and their potential role as biomarkers. CONCLUSIONS:The rapid expansion of tools and pipelines for isolating, measuring, and annotating these entities suggests that caution in interpreting results is warranted until these methodologies are rigorously validated. Most investigators have focused on investigating the functional role of single RNA entities, but studies suggest complex interaction between different RNA molecules. The use of network approaches and advanced computational tools to understand the interaction of different noncoding RNA species to mediate a particular phenotype may be required to fully comprehend the function of noncoding RNAs in mediating disease phenotypes.

Progressive fibrosing interstitial lung disease (PF-ILD) has been redefined as a new clinical syndrome that shares similar genetics, pathophysiology, and natural history to idiopathic pulmonary fibrosis (IPF). IPF is the most common form of idiopathic interstitial pneumonias, which is progressive in nature and is associated with significant mortality. Therapies targeting an inflammatory and/or immune response have not been consistently effective or well tolerated in patients with IPF. The two antifibrotic drugs approved for IPF treatment, nintedanib and pirfenidone, have been shown to reduce lung function decline in PF-ILD. Novel uses of antifibrotic therapy are emerging due to a paucity of evidence-based treatments for multiple ILD subtypes. In this review, we describe the current body of knowledge on antifibrotic therapy and immunomodulators in PF-ILD, drawing from experience in IPF where appropriate.

Screening measures for depression developed in high-income countries have not always demonstrated strong psychometric properties in South Africa and with people living with HIV (PLWH). The present study explored the psychometric properties of the 16-item South African Depression Scale (SADS) comprised of idioms of distress specific to isiXhosa culture in PLWH. The SADS was administered to 137 Xhosa-speaking PLWH who met diagnostic criteria for major depressive disorder (MDD) together with the Hamilton Depression Scale (HAM-D) and the Center for Epidemiological Studies Depression Scale (CES-D). We conducted exploratory factor analysis, correlation, and reliability statistics. Four factors of the SADS emerged: Sadness, lethargy/burdened, anhedonia/withdrawal, and cognitive/somatic. All factors correlated significantly with the HAM-D and CES-D. Internal consistency of the overall measure was high (α = .89). The SADS promises to be a robust measure of depression in isiXhosa-speaking PLWH in South Africa likely due to the inclusion of local idioms of distress.

Cryopreserved human skin allografts (CHSAs) are used for the coverage of major burns when donor sites for autografts are insufficiently available and have clinically shown beneficial effects on chronic non-healing wounds. However, the biologic mechanisms behind the regenerative properties of CHSA remain elusive. Furthermore, the impact of cryopreservation on the immunogenicity of CHSA has not been thoroughly investigated and raised concerns with regard to their clinical application. To investigate the importance and fate of living cells, we compared cryopreserved CHSA with human acellular dermal matrix (ADM) grafts in which living cells had been removed by chemical processing. Both grafts were subcutaneously implanted into C57BL/6 mice and explanted after 1, 3, 7, and 28 days (n = 5 per group). A sham surgery where no graft was implanted served as a control. Transmission electron microscopy (TEM) and flow cytometry were used to characterise the ultrastructure and cells within CHSA before implantation. Immunofluorescent staining of tissue sections was used to determine the immune reaction against the implanted grafts, the rate of apoptotic cells, and vascularisation as well as collagen content of the overlaying murine dermis. Digital quantification of collagen fibre alignment on tissue sections was used to quantify the degree of fibrosis within the murine dermis. A substantial population of live human cells with intact organelles was identified in CHSA prior to implantation. Subcutaneous pockets with implanted xenografts or ADMs healed without clinically apparent rejection and with a similar cellular immune response. CHSA implantation largely preserved the cellularity of the overlying murine dermis, whereas ADM was associated with a significantly higher rate of cellular apoptosis, identified by cleaved caspase-3 staining, and a stronger dendritic cell infiltration of the murine dermis. CHSA was found to induce a local angiogenic response, leading to significantly more vascularisation of the murine dermis compared with ADM and sham surgery on day 7. By day 28, aggregate collagen-1 content within the murine dermis was greater following CHSA implantation compared with ADM. Collagen fibre alignment of the murine dermis, correlating with the degree of fibrosis, was significantly greater in the ADM group, whereas CHSA maintained the characteristic basket weave pattern of the native murine dermis. Our data indicate that CHSAs promote angiogenesis and collagen-1 production without eliciting a significant fibrotic response in a xenograft model. These findings may provide insight into the beneficial effects clinically observed after treatment of chronic wounds and burns with CHSA.