Medical Molecular Biology Commons^™

The Emerging Spectrum Of Cardiopulmonary Pathology Of The Coronavirus Disease 2019 (Covid-19): Report Of 3 Autopsies From Houston, Texas, And Review Of Autopsy Findings From Other United States Cities, Manish Bodas, Bharathiraja Subramaniyan, Harry Karmouty-Quintana, Peter F Vitiello, Matthew S Walters

Faculty, Staff and Student Publications

The mammalian respiratory system or lung is a tree-like branching structure, and the main site of gas exchange with the external environment. Structurally, the lung is broadly classified into the proximal (or conducting) airways and the distal alveolar region, where the gas exchange occurs. In parallel with the respiratory tree, the pulmonary vasculature starts with large pulmonary arteries that subdivide rapidly ending in capillaries adjacent to alveolar structures to enable gas exchange. The NOTCH signalling pathway plays an important role in lung development, differentiation and regeneration post-injury. Signalling via the NOTCH pathway is mediated through activation of four NOTCH receptors …

A New Pathogenic Polg Variant, S Nicholas Russo, Ekta G Shah, William C Copeland, Mary Kay Koenig

Faculty, Staff and Student Publications

POLG gene mutations are the most common causes of inherited mitochondrial disorders. The enzyme produced by this gene is responsible for the replication and repair of mitochondrial DNA. To date, around 300 pathogenic variants have been described in this gene. The resulting clinical outcomes of POLG mutations are widely variable in both phenotype and severity. There is considerable overlap in the phenotype of the so-called POLG syndromes with no clear genotype-phenotype correlation. Here we describe a newly discovered pathogenic variant in the POLG gene in a 7-year-old male that died of uncontrollable refractory status epilepticus. Genetic epilepsy panel sequencing identified …

Distinguishing Intrathyroid Parathyroid Adenoma From Colloid Nodules And Papillary Thyroid Carcinomas Using Multiphasic Multidetector Computed Tomography, J Matthew Debnam, T Linda Chi, Michael Kwon, Jia Sun, Dawid Schellingerhout, Brandon T Golant, Salmaan Ahmed, Nancy D Perrier, Thinh Vu

Faculty, Staff and Student Publications

OBJECTIVE: The aim of the study is to determine whether multiphase multidetector computed tomography (4D-MDCT) can differentiate between intrathyroid parathyroid adenomas (ITPAs), colloid nodules, and papillary thyroid carcinoma (PTC).

METHODS: We studied 22 ITPAs, 22 colloid nodules, and 11 PTCs in 55 patients. Hounsfield unit (HU) values of the nodules were measured on 4D-MDCT in the precontrast, arterial, venous, and delayed phases. Raw HU values, phase with peak enhancement, and washout percentages between the phases were evaluated.

RESULTS: Regardless of size, all ITPAs (22/22) showed peak enhancement in the arterial phase, which was significantly greater than both colloid nodules (15/22) …

Amphotericin B Resistance In Leishmania Mexicana: Alterations To Sterol Metabolism And Oxidative Stress Response, Edubiel A Alpizar-Sosa, Nur Raihana Binti Ithnin, Wenbin Wei, Andrew W Pountain, Stefan K Weidt, Anne M Donachie, Ryan Ritchie, Emily A Dickie, Richard J S Burchmore, Paul W Denny, Michael P Barrett

Faculty, Staff and Student Publications

Amphotericin B is increasingly used in treatment of leishmaniasis. Here, fourteen independent lines of Leishmania mexicana and one L. infantum line were selected for resistance to either amphotericin B or the related polyene antimicrobial, nystatin. Sterol profiling revealed that, in each resistant line, the predominant wild-type sterol, ergosta-5,7,24-trienol, was replaced by other sterol intermediates. Broadly, two different profiles emerged among the resistant lines. Whole genome sequencing then showed that these distinct profiles were due either to mutations in the sterol methyl transferase (C24SMT) gene locus or the sterol C5 desaturase (C5DS) gene. In three lines an additional deletion of …

Intermediary Role Of Lung Alveolar Type 1 Cells In Epithelial Repair Upon Sendai Virus Infection, Belinda J Hernandez, Margo P Cain, Anne M Lynch, Jose R Flores, Michael J Tuvim, Burton F Dickey, Jichao Chen

Faculty, Staff and Student Publications

The lung epithelium forms the first barrier against respiratory pathogens and noxious chemicals; however, little is known about how more than 90% of this barrier, made of AT1 (alveolar type 1) cells, responds to injury. Using the Sendai virus to model natural infection in mice, we find evidence that AT1 cells have an intermediary role by persisting in areas depleted of AT2 cells, upregulating IFN responsive genes, and receding from invading airway cells. Sendai virus infection mobilizes airway cells to form alveolar SOX2+ (Sry-box 2+) clusters without differentiating into AT1 or AT2 cells. Large AT2 cell-depleted areas remain covered by …

Association Of Methylenetetrahydrofolate Reductase Rs1801133 Genetic Variants With Type 2 Diabetes Mellitus And Diabetic Nephropathy, Aysegul Bayramoglu, Gokhan Bayramoglu, Halil Ibrahım Guler, Nezaket Coban, Mustafa Çagatay Korkmaz

Makara Journal of Health Research

Background: Type 2 diabetes mellitus (T2DM) is a complex metabolic disease with a genetic predisposition. Methylenetetrahydrofolatereductase (MTHFR) gene is one of the candidate genes associated with T2DM and diabetic nephropathy (DN). This research was carried out to determine the frequency of the C677T polymorphism (rs1801133) of the MTHFR gene and examine the role of rs1801133 polymorphism in T2DM and DN development.

Methods: DNA was obtained from peripheral blood samples (273 samples) using a DNA isolation kit. MTHFR rs1801133 polymorphism was determined using polymerase chain reaction (PCR), restriction fragment length polymorphism (RFLP), and electrophoresis. PCR products were cut by …

Healthy Exosomes And Their Effects On Diabetic Cardiomyocytes, Miguel A. Garza, Genaro A. Ramírez-Correa, Maria Lourdes Garza-Rodríguez, Andres J. Medina

MEDI 9331 Scholarly Activities Clinical Years

Extracellular Vesicles, and more specifically, exosomes, are essential for effective cell-to-cell communication in a wide variety of tissues. In the last couple of decades, these nanovesicles have been proven to be active participants and regulators in many disease processes; therefore, their therapeutic effects have been widely studied and proven in various cardiovascular diseases both, in vitro and in vivo. Thus, this study aims at assessing the effects of running healthy mice exosomes on cardiomyocyte and cardiac tissue samples obtained from diabetic mice. Here, we successfully extract exosomes from mice plasma and detect their presence through the use of anti-CD9 and …

G Protein-Coupled Receptor Kinase 6 (Grk6) Regulates Insulin Processing And Secretion Via Effects On Proinsulin Conversion To Insulin, Matthew J Varney, Wouter Steyaert, Paul J Coucke, Joris R Delanghe, David E Uehling, Babu Joseph, Richard Marcellus, Rima Al-Awar, Jeffrey L Benovic

Department of Biochemistry and Molecular Biology Faculty Papers

Recent studies identified a missense mutation in the gene coding for G protein-coupled receptor kinase 6 (GRK6) that segregates with type 2 diabetes (T2D). To better understand how GRK6 might be involved in T2D, we used pharmacological inhibition and genetic knockdown in the mouse β-cell line, MIN6, to determine whether GRK6 regulates insulin dynamics. We show inhibition of GRK5 and GRK6 increased insulin secretion but reduced insulin processing while GRK6 knockdown revealed these same processing defects with reduced levels of cellular insulin. GRK6 knockdown cells also had attenuated insulin secretion but enhanced proinsulin secretion consistent with decreased processing. In support …

Regulation Of Drosophila Oviduct Muscle Contractility By Octopamine, Sonali A Deshpande, Ethan W Rohrbach, James D Asuncion, Jenna Harrigan, Aditya Eamani, Ellery H Schlingmann, Daniel J Suto, Pei-Tseng Lee, Felix E Schweizer, Hugo J Bellen, David E Krantz

Duncan NRI Faculty and Staff Publications

Octopamine is essential for egg-laying in

Structure-Based Design Of Stapled Peptides That Bind Gabarap And Inhibit Autophagy, Hawley Brown, Mia Chung, Alina Üffing, Nefeli Batistatou, Tiffany Tsang, Samantha Doskocil, Weiqun Mao, Dieter Willbold, Robert C Bast, Zhen Lu, Oliver H Weiergräber, Joshua A Kritzer

Faculty, Staff and Student Publications

The LC3/GABARAP family of proteins is involved in nearly every stage of autophagy. Inhibition of LC3/GABARAP proteins is a promising approach to blocking autophagy, which sensitizes advanced cancers to DNA-damaging chemotherapy. Here, we report the structure-based design of stapled peptides that inhibit GABARAP with nanomolar affinities. Small changes in staple structure produced stapled peptides with very different binding modes and functional differences in LC3/GABARAP paralog selectivity, ranging from highly GABARAP-specific to broad inhibition of both subfamilies. The stapled peptides exhibited considerable cytosolic penetration and resistance to biological degradation. They also reduced autophagic flux in cultured ovarian cancer cells and sensitized …

Gray And White Matter Abnormality In Patients With T2dm-Related Cognitive Dysfunction: A Systemic Review And Meta-Analysis, Teng Ma, Ze-Yang Li, Ying Yu, Bo Hu, Yu Han, Min-Hua Ni, Yu-Xiang Huang, Hao-Han Chen, Wen Wang, Lin-Feng Yan, Guang-Bin Cui

Faculty, Staff and Student Publications

Aims/hypothesis

Brain structure abnormality in patients with type 2 diabetes mellitus (T2DM)-related cognitive dysfunction (T2DM-CD) has been reported for decades in magnetic resonance imaging (MRI) studies. However, the reliable results were still unclear. This study aimed to make a systemic review and meta-analysis to find the significant and consistent gray matter (GM) and white matter (WM) alterations in patients with T2DM-CD by comparing with the healthy controls (HCs).

Methods

Published studies were systemically searched from PubMed, MEDLINE, Cochrane Library and Web of Science databases updated to November 14, 2021. Studies reporting abnormal GM or WM between patients with T2DM-CD and …

Twist1 Interacts With Β/Δ-Catenins During Neural Tube Development And Regulates Fate Transition In Cranial Neural Crest Cells, Jessica W Bertol, Shelby Johnston, Rabia Ahmed, Victoria K Xie, Kelsea M Hubka, Lissette Cruz, Larissa Nitschke, Marta Stetsiv, Jeremy P Goering, Paul Nistor, Sally Lowell, Hanne Hoskens, Peter Claes, Seth M Weinberg, Irfan Saadi, Mary C Farach-Carson, Walid D Fakhouri

Faculty, Staff and Student Publications

Cell fate determination is a necessary and tightly regulated process for producing different cell types and structures during development. Cranial neural crest cells (CNCCs) are unique to vertebrate embryos and emerge from the neural plate borders into multiple cell lineages that differentiate into bone, cartilage, neurons and glial cells. We have previously reported that Irf6 genetically interacts with Twist1 during CNCC-derived tissue formation. Here, we have investigated the mechanistic role of Twist1 and Irf6 at early stages of craniofacial development. Our data indicate that TWIST1 is expressed in endocytic vesicles at the apical surface and interacts with β/δ-catenins during neural …

Changes Of Brain Function In Patients With Type 2 Diabetes Mellitus Measured By Different Analysis Methods: A New Coordinate-Based Meta-Analysis Of Neuroimaging, Ze-Yang Li, Teng Ma, Ying Yu, Bo Hu, Yu Han, Hao Xie, Min-Hua Ni, Zhu-Hong Chen, Yang-Ming Zhang, Yu-Xiang Huang, Wen-Hua Li, Wen Wang, Lin-Feng Yan, Guang-Bin Cui

Faculty, Staff and Student Publications

OBJECTIVE: Neuroimaging meta-analysis identified abnormal neural activity alterations in patients with type 2 diabetes mellitus (T2DM), but there was no consistency or heterogeneity analysis between different brain imaging processing strategies. The aim of this meta-analysis was to determine consistent changes of regional brain functions in T2DM

METHODS: Since the indicators obtained using varied post-processing methods reflect different neurophysiological and pathological characteristics, we further conducted a coordinate-based meta-analysis (CBMA) of the two categories of neuroimaging literature, which were grouped according to similar data processing methods: one group included regional homogeneity (ReHo), independent component analysis (ICA), and degree centrality (DC) studies, while …

Hematopoietic-Mesenchymal Signals Regulate The Properties Of Mesenchymal Stem Cells, Sanshiro Kanazawa, Hiroyuki Okada, Dan Riu, Yo Mabuchi, Chihiro Akazawa, Junichi Iwata, Kazuto Hoshi, Atsuhiko Hikita

Faculty, Staff and Student Publications

It is well known that the properties of hematopoietic stem/progenitor cells (HSCs), such as their self-renewal ability and multipotency, are maintained through interactions with mesenchymal stem/stromal cells (MSCs). MSCs are rare cells that are present in the bone marrow and are useful for clinical applications due to their functional ability. To obtain the necessary number of cells, MSCs must be cultured to expand, but this causes a remarkable decrease in stem cell properties, such as multipotency and proliferation ability. In this study, we show that the c-Mpl signal, which is related to the maintenance of hematopoietic stem cells, has an …

Integrated Dna Copy Number And Expression Profiling Identifies Igf1r As A Prognostic Biomarker In Pediatric Osteosarcoma, Aaron M Taylor, Jiayi M Sun, Alexander Yu, Horatiu Voicu, Jianhe Shen, Donald A Barkauskas, Timothy J Triche, Julie M Gastier-Foster, Tsz-Kwong Man, Ching C Lau

Center for Medical Ethics and Health Policy Staff Publications

Osteosarcoma is a primary malignant bone tumor arising from bone-forming mesenchymal cells in children and adolescents. Despite efforts to understand the biology of the disease and identify novel therapeutics, the survival of osteosarcoma patients remains dismal. We have concurrently profiled the copy number and gene expression of 226 osteosarcoma samples as part of the Strategic Partnering to Evaluate Cancer Signatures (SPECS) initiative. Our results demonstrate the heterogeneous landscape of osteosarcoma in younger populations by showing the presence of genome-wide copy number abnormalities occurring both recurrently among samples and in a high frequency. Insulin growth factor receptor 1 (IGF1R) is a …

Cranial Base Synchondrosis Lacks Pthrp-Expressing Column-Forming Chondrocytes, Shawn A Hallett, Annabelle Zhou, Curtis Herzog, Ariel Arbiv, Wanida Ono, Noriaki Ono

Faculty, Staff and Student Publications

The cranial base contains a special type of growth plate termed the synchondrosis, which functions as the growth center of the skull. The synchondrosis is composed of bidirectional opposite-facing layers of resting, proliferating, and hypertrophic chondrocytes, and lacks the secondary ossification center. In long bones, the resting zone of the epiphyseal growth plate houses a population of parathyroid hormone-related protein (PTHrP)-expressing chondrocytes that contribute to the formation of columnar chondrocytes. Whether PTHrP+ chondrocytes in the synchondrosis possess similar functions remains undefined. Using Pthrp-mCherry knock-in mice, we found that PTHrP+ chondrocytes predominantly occupied the lateral wedge-shaped area of the synchondrosis, unlike …

Glyoxal Fixation Is Optimal For Immunostaining Of Brain Vessels, Pericytes And Blood-Brain Barrier Proteins, Sithara Thomas, Jayanarayanan Sadanandan, Spiros L Blackburn, Devin W Mcbride, Ari Dienel, Sungha Hong, Hussein A Zeineddine, Peeyush Kumar Thankamani

Faculty, Staff and Student Publications

Brain vascular staining is very important for understanding cerebrovascular pathologies. 4% paraformaldehyde is considered the gold standard fixation technique for immunohistochemistry and it revolutionized the examination of proteins in fixed tissues. However, this fixation technique produces inconsistent immunohistochemical staining results due to antigen masking. Here, we test a new fixation protocol using 3% glyoxal and demonstrate that this method improves the staining of the brain vasculature, pericytes, and tight junction proteins compared to 4% paraformaldehyde. Use of this new fixation technique will provide more detailed information about vascular protein expressions, their distributions, and colocalizations with other proteins at the molecular …

Comparison Of Flash-Free And Conventional Bonding Systems: A Systematic Review And Meta-Analysis, He Wang, Ge Feng, Bo Hu, Haonan Tian, Yunchun Kuang, Tingwei Zhang, Jinlin Song

Faculty, Staff and Student Publications

OBJECTIVES: To review the literature systematically to compare the performance of adhesive precoated flash-free bonding systems with conventional adhesive precoated (APC) and operator-coated (OPC) bonding systems.

MATERIALS AND METHODS: PubMed, Cochrane Library, Web of Science, and Embase were searched for potential eligible studies. Study selection and data collection were conducted independently. Statistical analysis was performed by Review Manager 5.3. The Cochran Q test was used to test heterogeneity in the included studies. Risk of bias was evaluated using Cochrane RoB 2.0 tool for randomized controlled trials.

RESULTS: Six studies were included and the overall risk-of-bias judgment was low risk of …

Renin-Angiotensin System In Huntington's Disease: Evidence From Animal Models And Human Patients, Lucas M Kangussu, Natalia P Rocha, Priscila A C Valadão, Thatiane C G Machado, Kívia B Soares, Julliane V Joviano-Santos, Leigh B Latham, Gabriela D Colpo, Ana Flávia Almeida-Santos, Erin Furr Stimming, Ana Cristina Simões E Silva, Antônio L Teixeira, Aline Silva Miranda, Cristina Guatimosim

Faculty, Staff and Student Publications

The Renin-Angiotensin System (RAS) is expressed in the central nervous system and has important functions that go beyond blood pressure regulation. Clinical and experimental studies have suggested that alterations in the brain RAS contribute to the development and progression of neurodegenerative diseases. However, there is limited information regarding the involvement of RAS components in Huntington's disease (HD). Herein, we used the HD murine model, (BACHD), as well as samples from patients with HD to investigate the role of both the classical and alternative axes of RAS in HD pathophysiology. BACHD mice displayed worse motor performance in different behavioral tests alongside …

Neuromuscular Junction Pathology Is Correlated With Differential Motor Unit Vulnerability In Spinal And Bulbar Muscular Atrophy, Elana Molotsky, Y Liu, Andrew P Lieberman, Diane E Merry

Department of Biochemistry and Molecular Biology Faculty Papers

Spinal and bulbar muscular atrophy (SBMA) is an X-linked, neuromuscular neurodegenerative disease for which there is no cure. The disease is characterized by a selective decrease in fast-muscle power (e.g., tongue pressure, grip strength) accompanied by a selective loss of fast-twitch muscle fibers. However, the relationship between neuromuscular junction (NMJ) pathology and fast-twitch motor unit vulnerability has yet to be explored. In this study, we used a cross-model comparison of two mouse models of SBMA to evaluate neuromuscular junction pathology, glycolytic-to-oxidative fiber-type switching, and cytoskeletal alterations in pre- and postsynaptic termini of tibialis anterior (TA), gastrocnemius, and soleus hindlimb muscles. …