Medicine and Health Sciences Commons^™

Current Strategies For Increasing Knock-In Efficiency In Crispr/Cas9-Based Approaches, Andrés Felipe Leal, Angelica María Herreno-Pachón, Eliana Benincore-Flórez, Amali Karunathilaka, Shunji Tomatsu

Department of Pediatrics Faculty Papers

Since its discovery in 2012, the clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR-associated protein 9 (Cas9) system has supposed a promising panorama for developing novel and highly precise genome editing-based gene therapy (GT) alternatives, leading to overcoming the challenges associated with classical GT. Classical GT aims to deliver transgenes to the cells via their random integration in the genome or episomal persistence into the nucleus through lentivirus (LV) or adeno-associated virus (AAV), respectively. Although high transgene expression efficiency is achieved by using either LV or AAV, their nature can result in severe side effects in humans. For instance, …

Mucopolysaccharidosis Iva: Current Disease Models And Drawbacks, Andrés Felipe Leal, Carlos Javier Alméciga-Díaz, Shunji Tomatsu

Department of Pediatrics Faculty Papers

Mucopolysaccharidosis IVA (MPS IVA) is a rare disorder caused by mutations in the N-acetylgalactosamine-6-sulfate-sulfatase (GALNS) encoding gene. GALNS leads to the lysosomal degradation of the glycosaminoglyccreasans keratan sulfate and chondroitin 6-sulfate. Impaired GALNS enzymes result in skeletal and non-skeletal complications in patients. For years, the MPS IVA pathogenesis and the assessment of promising drugs have been evaluated using in vitro (primarily fibroblasts) and in vivo (mainly mouse) models. Even though value information has been raised from those studies, these models have several limitations. For instance, chondrocytes have been well recognized as primary cells affected in MPS IVA and responsible for …

Evaluation Of The Orally Bioavailable 4-Phenylbutyrate-Tethered Trichostatin A Analogue Ar42 In Models Of Spinal Muscular Atrophy, Casey J. Lumpkin, Ashlee W. Harris, Andrew J. Connell, Ryan W. Kirk, Joshua A. Whiting, Luciano Saieva, Livio Pellizzoni, Arthur H.M. Burghes, Matthew E.R. Butchbach

Department of Pediatrics Faculty Papers

Proximal spinal muscular atrophy (SMA) is a leading genetic cause for infant death in the world and results from the selective loss of motor neurons in the spinal cord. SMA is a consequence of low levels of SMN protein and small molecules that can increase SMN expression are of considerable interest as potential therapeutics. Previous studies have shown that both 4-phenylbutyrate (4PBA) and trichostatin A (TSA) increase SMN expression in dermal fibroblasts derived from SMA patients. AR42 is a 4PBA-tethered TSA derivative that is a very potent histone deacetylase inhibitor. SMA patient fibroblasts were treated with either AR42, AR19 (a …

Effect Of The Butyrate Prodrug Pivaloyloxymethyl Butyrate (An9) On A Mouse Model For Spinal Muscular Atrophy., Jonathan D. Edwards, Matthew E.R. Butchbach

Department of Pediatrics Faculty Papers

Spinal muscular atrophy (SMA) is an early-onset motor neuron disease that leads to loss of muscle function. Butyrate (BA)-based compounds markedly improve the survival and motor phenotype of SMA mice. In this study, we examine the protective effects of the BA prodrug pivaloyloxymethyl butyrate (AN9) on the survival of SMNΔ7 SMA mice. Oral administration of AN9 beginning at PND04 almost doubled the average lifespan of SMNΔ7 SMA mice. AN9 treatment also increased the growth rate of SMNΔ7 SMA mice when compared to vehicle-treated SMNΔ7 SMA mice. In conclusion, BA prodrugs like AN9 have ameliorative effects on SMNΔ7 SMA mice.

Identification Of Early Gene Expression Changes In Primary Cultured Neurons Treated With Topoisomerase I Poisons., Sharyn L. Rossi, Casey J. Lumpkin, Ashlee W. Harris, Jennifer Holbrook, Cinsley Gentillon, Suzanne M. Mccahan, Wenlan Wang, Matthew E.R. Butchbach

Department of Pediatrics Faculty Papers

Topoisomerase 1 (TOP1) poisons like camptothecin (CPT) are currently used in cancer chemotherapy but these compounds can have damaging, off-target effects on neurons leading to cognitive, sensory and motor deficits. To understand the molecular basis for the enhanced sensitivity of neurons to CPT, we examined the effects of compounds that inhibit TOP1-CPT, actinomycin D (ActD) and β-lapachone (β-Lap)-on primary cultured rat motor (MN) and cortical (CN) neurons as well as fibroblasts. Neuronal cells expressed higher levels of Top1 mRNA than fibroblasts but transcript levels are reduced in all cell types after treatment with CPT. Microarray analysis was performed to identify …

Identification Of Factors Associated With Good Response To Growth Hormone Therapy In Children With Short Stature: Results From The Answer Program®., Peter A Lee, John Germak, Robert Gut, Naum Khutoryansky, Judith Ross

Department of Pediatrics Faculty Papers

UNLABELLED: ABSTRACT:

OBJECTIVE: To identify factors associated with growth in children on growth hormone (GH) therapy using data from the American Norditropin Studies: Web-enabled Research (ANSWER) Program® registry.

METHODS: GH-naïve children with GH deficiency, multiple pituitary hormone deficiency, idiopathic short stature, Turner syndrome, or a history of small for gestational age were eligible (N = 1,002). Using a longitudinal statistical approach, predictive factors were identified in patients with GHD for change from baseline in height standard deviation score (ΔHSDS) following 2 years of treatment.

RESULTS: Gradual increases in ΔHSDS over time were observed for all diagnostic categories. Significant predictive factors …

Proteomic Assessment Of A Cell Model Of Spinal Muscular Atrophy., Chia-Yen Wu, Dosh Whye, Lisa Glazewski, Leila Choe, Douglas Kerr, Kelvin H Lee, Robert W Mason, Wenlan Wang

Department of Pediatrics Faculty Papers

BACKGROUND: Deletion or mutation(s) of the survival motor neuron 1 (SMN1) gene causes spinal muscular atrophy (SMA), a neuromuscular disease characterized by spinal motor neuron death and muscle paralysis. Complete loss of the SMN protein is embryonically lethal, yet reduced levels of this protein result in selective death of motor neurons. Why motor neurons are specifically targeted by SMN deficiency remains to be determined. In this study, embryonic stem (ES) cells derived from a severe SMA mouse model were differentiated into motor neurons in vitro by addition of retinoic acid and sonic hedgehog agonist. Proteomic and western blot analyses were …

Animal Bite Infections., Joel D. Klein, Md

Department of Pediatrics Faculty Papers

Animal bites have become alarmingly common and may represent a quiet epidemic. It is estimated that between 1 and 3.5 million animal bites occur annually in the United States. The highest incidence has consistently been in 5-to-14-year-old schoolchildren, who have greater contact with animals, especially house pets, on a daily basis. This article discusses the epidemiology, microbiology, clinical findings and management of animal bites infections.