Medical Specialties Commons^™

Perioperative Acute Kidney Injury, Sam D Gumbert, Felix Kork, Maisie L Jackson, Naveen Vanga, Semhar J Ghebremichael, Christy Y Wang, Holger K Eltzschig

Faculty, Staff and Students Publications

Perioperative organ injury is among the leading causes of morbidity and mortality of surgical patients. Among different types of perioperative organ injury, acute kidney injury occurs particularly frequently and has an exceptionally detrimental effect on surgical outcomes. Currently, acute kidney injury is most commonly diagnosed by assessing increases in serum creatinine concentration or decreased urine output. Recently, novel biomarkers have become a focus of translational research for improving timely detection and prognosis for acute kidney injury. However, specificity and timing of biomarker release continue to present challenges to their integration into existing diagnostic regimens. Despite many clinical trials using various …

Aromatase Inhibitors Plus Weight Loss Improves The Hormonal Profile Of Obese Hypogonadal Men Without Causing Major Side Effects, Georgia Colleluori, Rui Chen, Christie G Turin, Francesca Vigevano, Clifford Qualls, Biju Johnson, Sanjay Mediwala, Dennis T Villareal, Reina Armamento-Villareal

Faculty, Staff and Students Publications

Objective: In obese men, the increased expression of the aromatase enzyme in adipose tissue leads to high conversion of androgens to estrogens contributing to hypogonadotropic hypogonadism (HHG). Our objective is to evaluate efficacy and safety of weight loss (WL) plus aromatase inhibitor (AI) therapy in severely obese men with HHG. We hypothesize that AI+WL will be more effective as compared to WL alone in improving the hormonal profile, thus muscle strength and symptoms of HHG (primary outcomes), with no significant adverse effects on lean mass, metabolic profile, and bone mineral density (secondary outcomes).

Design: Randomized double-blind placebo-controlled pilot trial.

Methods: …

Development Of A Hybrid, Interprofessional, Interactive Quality Improvement Curriculum As A Model For Continuing Professional Development, Isabelle S Kusters, Megan E Gregory, Jennifer L Bryan, Sylvia J Hysong, Lechauncy D Woodard, Aanand D Naik, Kyler M Godwin

Faculty, Staff and Students Publications

Over the past 20 years, there has been an increased focus on quality improvement (QI) in health care, which is critical in achieving care that is patient-centered, safer, timelier, and more effective, efficient, and equitable. At the center of this movement is QI education, which is known to lead to learning, behavior change, and improved outcomes. However, there is a need for the development and provision of long-duration, interactive, interprofessional training in QI, to allow for in-depth learning and application of learned skills. To this end, we designed a curriculum for an established interprofessional, interactive, web-based QI fellowship for doctorally …

Single-Nuclei Rna-Seq On Human Retinal Tissue Provides Improved Transcriptome Profiling, Qingnan Liang, Rachayata Dharmat, Leah Owen, Akbar Shakoor, Yumei Li, Sangbae Kim, Albert Vitale, Ivana Kim, Denise Morgan, Shaoheng Liang, Nathaniel Wu, Ken Chen, Margaret M Deangelis, Rui Chen

Faculty, Staff and Students Publications

Single-cell RNA-seq is a powerful tool in decoding the heterogeneity in complex tissues by generating transcriptomic profiles of the individual cell. Here, we report a single-nuclei RNA-seq (snRNA-seq) transcriptomic study on human retinal tissue, which is composed of multiple cell types with distinct functions. Six samples from three healthy donors are profiled and high-quality RNA-seq data is obtained for 5873 single nuclei. All major retinal cell types are observed and marker genes for each cell type are identified. The gene expression of the macular and peripheral retina is compared to each other at cell-type level. Furthermore, our dataset shows an …

Electrochemical Hydrogen Evolution Over Hydrothermally Synthesized Re-Doped Mos2 Flower-Like Microspheres, Juan Aliaga, Pablo Vera, Juan Araya, Luis Ballesteros, Julio Urzúa, Mario Farías, Francisco Paraguay-Delgado, Gabriel Alonso-Núñez, Guillermo González, Eglantina Benavente

Faculty, Staff and Students Publications

In this research, we report a simple hydrothermal synthesis to prepare rhenium (Re)- doped MoS2 flower-like microspheres and the tuning of their structural, electronic, and electrocatalytic properties by modulating the insertion of Re. The obtained compounds were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS). Structural, morphological, and chemical analyses confirmed the synthesis of poorly crystalline Re-doped MoS2 flower-like microspheres composed of few stacked layers. They exhibit enhanced hydrogen evolution reaction (HER) performance with low overpotential of 210 mV at current density of 10 mA/cm2, with a …

Examining Multiple Cellular Pathways At Once Using Multiplex Hextuple Luciferase Assaying, Alejandro Sarrion-Perdigones, Lyra Chang, Yezabel Gonzalez, Tatiana Gallego-Flores, Damian W Young, Koen J T Venken

Faculty, Staff and Students Publications

Sensitive simultaneous assessment of multiple signaling pathways within the same cells requires orthogonal reporters that can assay over large dynamic ranges. Luciferases are such genetically encoded candidates due to their sensitivity, versatility, and cost-effectiveness. We expand luciferase multiplexing in post-lysis endpoint luciferase assays from two to six. Light emissions are distinguished by a combination of distinct substrates and emission spectra deconvolution. All six luciferase reporter units are stitched together into one plasmid facilitating delivery of all reporter units through a process we termed solotransfection, minimizing experimental errors. We engineer a multiplex hextuple luciferase assay to probe pathway fluxes through five …

Residues And Residue Pairs Of Evolutionary Importance Differentially Direct Signaling Bias Of D2 Dopamine Receptors, María E Terrón-Díaz, Sara J Wright, Melina A Agosto, Olivier Lichtarge, Theodore G Wensel

Faculty, Staff and Students Publications

The D2 dopamine receptor and the serotonin 5-hydroxytryptamine 2A receptor (5-HT2A) are closely-related G-protein–coupled receptors (GPCRs) from the class A bioamine subfamily. Despite structural similarity, they respond to distinct ligands through distinct downstream pathways, whose dysregulation is linked to depression, bipolar disorder, addiction, and psychosis. They are important drug targets, and it is important to understand how their bias toward G-protein versus β-arrestin signaling pathways is regulated. Previously, evolution-based computational approaches, difference Evolutionary Trace and Evolutionary Trace–Mutual information (ET-Mip), revealed residues and residue pairs that, when switched in the D2 receptor to the corresponding residues from 5-HT2A, altered ligand potency …

Ultrafast Two-Photon Imaging Of A High-Gain Voltage Indicator In Awake Behaving Mice, Vincent Villette, Mariya Chavarha, Ivan K Dimov, Jonathan Bradley, Lagnajeet Pradhan, Benjamin Mathieu, Stephen W Evans, Simon Chamberland, Dongqing Shi, Renzhi Yang, Benjamin B Kim, Annick Ayon, Abdelali Jalil, François St-Pierre, Mark J Schnitzer, Guoqiang Bi, Katalin Toth, Jun Ding, Stéphane Dieudonné, Michael Z Lin

Faculty, Staff and Students Publications

Optical interrogation of voltage in deep brain locations with cellular resolution would be immensely useful for understanding how neuronal circuits process information. Here, we report ASAP3, a genetically encoded voltage indicator with 51% fluorescence modulation by physiological voltages, submillisecond activation kinetics, and full responsivity under two-photon excitation. We also introduce an ultrafast local volume excitation (ULoVE) method for kilohertz-rate two-photon sampling in vivo with increased stability and sensitivity. Combining a soma-targeted ASAP3 variant and ULoVE, we show single-trial tracking of spikes and subthreshold events for minutes in deep locations, with subcellular resolution and with repeated sampling over days. In the …

Gna11 Brain Somatic Pathogenic Variant In An Individual With Phacomatosis Pigmentovascularis, Joseph M Sliepka, Sarah C Mcgriff, Linda Z Rossetti, Peyman Bizargity, Haley Streff, Yi-Shan Lee, Hongzheng Dai, Satyamaanasa Polubothu, Grace Lee, Vicky Ren, Jill V Hunter, Daniel J Curry, Fernando Scaglia, Adekunle M Adesina, Irfan Ali, Veronica Kinsler, Lindsay C Burrage, Dana Marafi

Faculty, Staff and Students Publications

OBJECTIVE: To describe the findings of histopathology and genotyping studies in affected brain tissue from an individual with phacomatosis pigmentovascularis (PPV).

METHODS: A retrospective chart review of a 2-year 10-month-old male with a clinical diagnosis of PPV cesiomarmorata (or type V) was performed. Clinical features, brain imaging and histopathology findings, and genotyping studies in his affected brain tissue are summarized.

RESULTS: The proband had a clinically severe neurologic phenotype characterized by global developmental delay, generalized hypotonia, and recurrent episodes of cardiac asystole in the setting of status epilepticus. A somatic pathogenic variant in

CONCLUSIONS: The finding of this variant in …

Bipolar Fresh Osteochondral Allograft Transplantation And Joint Reconstruction For Patellar And Trochlear Cartilage Defects, Omid Jalali, Zachary Vredenburgh, John Prodromo, Neilen Benvegnu, George Frederick Rick Hatch

Faculty, Staff and Students Publications

Patellar instability is a debilitating condition, and trauma due to the dislocations may severely damage the articular cartilage of the patellofemoral joint. The lack of healing capacity of cartilage makes treatment of such lesions challenging. In young patients, preservation of native bone and cartilage is a priority, and therefore arthroplasty procedures should be avoided even in relatively larger lesions. Fresh osteochondral allografting has been described for these difficult and complex cases, with recent studies showing promising results. In this surgical technique, we describe the use of bipolar osteochondral allografts of the patella and trochlea and patellofemoral joint reconstruction for large …

Results Of A Phase 1 Multicentre Investigation Of Dexmedetomidine Bolus And Infusion In Corrective Infant Cardiac Surgery, Athena F Zuppa, Susan C Nicolson, Nicole S Wilder, Juan C Ibla, Erin A Gottlieb, Kristin M Burns, Mario Stylianou, Felicia Trachtenberg, Hua Ni, Tera H Skeen, Dean B Andropoulos

Faculty, Staff and Students Publications

BACKGROUND: Dexmedetomidine (DEX) is increasingly used intraoperatively in infants undergoing cardiac surgery. This phase 1 multicentre study sought to: (i) determine the safety of DEX for cardiac surgery with cardiopulmonary bypass; (ii) determine the pharmacokinetics (PK) of DEX; (iii) create a PK model and dosing for steady-state DEX plasma levels; and (iv) validate the PK model and dosing.

METHODS: We included 122 neonates and infants (0-180 days) with D-transposition of the great arteries, ventricular septal defect, or tetralogy of Fallot. Dose escalation was used to generate NONMEM® PK modelling, and then validation was performed to achieve low (200-300 pg ml …

Structural Basis Of Amino Acid Surveillance By Higher-Order Trna-Mrna Interactions, Shuang Li, Zhaoming Su, Jean Lehmann, Vassiliki Stamatopoulou, Nikoleta Giarimoglou, Frances E Henderson, Lixin Fan, Grigore D Pintilie, Kaiming Zhang, Muyuan Chen, Steven J Ludtke, Yun-Xing Wang, Constantinos Stathopoulos, Wah Chiu, Jinwei Zhang

Faculty, Staff and Students Publications

Amino acid availability in Gram-positive bacteria is monitored by T-box riboswitches. T-boxes directly bind tRNAs, assess their aminoacylation state, and regulate the transcription or translation of downstream genes to maintain nutritional homeostasis. Here, we report cocrystal and cryo-EM structures of Geobacillus kaustophilus and Bacillus subtilis T-box-tRNA complexes, detailing their multivalent, exquisitely selective interactions. The T-box forms a U-shaped molecular vise that clamps the tRNA, captures its 3' end using an elaborate 'discriminator' structure, and interrogates its aminoacylation state using a steric filter fashioned from a wobble base pair. In the absence of aminoacylation, T-boxes clutch tRNAs and form a continuously …

Defining The Layers Of A Sensory Cilium With Storm And Cryoelectron Nanoscopy, Michael A Robichaux, Valencia L Potter, Zhixian Zhang, Feng He, Jun Liu, Michael F Schmid, Theodore G Wensel

Faculty, Staff and Students Publications

Primary cilia carry out numerous signaling and sensory functions, and defects in them, "ciliopathies," cause a range of symptoms, including blindness. Understanding of their nanometer-scale ciliary substructures and their disruptions in ciliopathies has been hindered by limitations of conventional microscopic techniques. We have combined cryoelectron tomography, enhanced by subtomogram averaging, with superresolution stochastic optical reconstruction microscopy (STORM) to define subdomains within the light-sensing rod sensory cilium of mouse retinas and reveal previously unknown substructures formed by resident proteins. Domains are demarcated by structural features such as the axoneme and its connections to the ciliary membrane, and are correlated with molecular …

A Proof-Of-Mechanism Study To Test Effects Of The Nmda Receptor Antagonist Lanicemine On Behavioral Sensitization In Individuals With Symptoms Of Ptsd, Marijn Lijffijt, Charles E Green, Nicholas Balderston, Tabish Iqbal, Megan Atkinson, Brittany Vo-Le, Bylinda Vo-Le, Brittany O'Brien, Christian Grillon, Alan C Swann, Sanjay J Mathew

Faculty, Staff and Students Publications

Background: Individuals with post-traumatic stress disorder (PTSD) have a heightened sensitivity to subsequent stressors, addictive drugs, and symptom recurrence, a form of behavioral sensitization. N-methyl-D-aspartate receptors (NMDARs) are involved in the establishment and activation of sensitized behavior.

Objective: We describe a protocol of a randomized placebo-controlled Phase 1b proof-of-mechanism trial to examine target engagement, safety, tolerability, and possible efficacy of the NMDAR antagonist lanicemine in individuals with symptoms of PTSD (Clinician Administered PTSD Scale [CAPS-5] score ≥ 25) and evidence of behavioral sensitization measured as enhanced anxiety-potentiated startle (APS; T-score ≥ 2.8).

Methods: Subjects (n = 24; age range 21–65) …

Is Whole-Exome Sequencing An Ethically Disruptive Technology? Perspectives Of Pediatric Oncologists And Parents Of Pediatric Patients With Solid Tumors, Laurence B Mccullough, Melody J Slashinski, Amy L Mcguire, Richard L Street, Christine M Eng, Richard A Gibbs, D William Parsons, Sharon E Plon

Faculty, Staff and Students Publications

BACKGROUND: It has been anticipated that physician and parents will be ill prepared or unprepared for the clinical introduction of genome sequencing, making it ethically disruptive.

PROCEDURE: As a part of the Baylor Advancing Sequencing in Childhood Cancer Care study, we conducted semistructured interviews with 16 pediatric oncologists and 40 parents of pediatric patients with cancer prior to the return of sequencing results. We elicited expectations and attitudes concerning the impact of sequencing on clinical decision making, clinical utility, and treatment expectations from both groups. Using accepted methods of qualitative research to analyze interview transcripts, we completed a thematic analysis …

Geospatial Analysis Of Food Environment Demonstrates Associations With Gestational Diabetes, Mk Kahr, Ma Suter, J Ballas, Sm Monga, W Lee, M Hu, Cd Shope, A Chesnokova, L Krannich, En Griffin, J Mastrobattista, Ga Dildy, Sl Strehlow, R Ramphul, Et Al.

Faculty, Staff and Students Publications

BACKGROUND: Gestational diabetes mellitus (GDM) is one of most common complications of pregnancy, with incidence rates varying by maternal age, race/ethnicity, obesity, parity, and family history. Given its increasing prevalence in recent decades, covariant environmental and sociodemographic factors may be additional determinants of GDM occurrence. OBJECTIVE: We hypothesized that environmental risk factors, in particular measures of the food environment, may be a diabetes contributor. We employed geospatial modeling in a populous US county to characterize the association of the relative availability of fast food restaurants and supermarkets to GDM. STUDY DESIGN: Utilizing a perinatal database with >4900 encoded antenatal and …

Activation Of Signal Transduction Pathways During Hepatic Oncogenesis, W Chung, M Kim, S De La Monte, L Longato, R Carlson, B L. Slagle, X Dong, J R. Wands

Faculty, Staff and Students Publications

BACKGROUND AND AIMS: Understanding the molecular pathogenesis of hepatocellular carcinoma (HCC) is essential to identify therapeutic targets. A hepatitis B virus (HBV) related double transgenic murine model was developed. METHODS: Liver specific expression of HBV X protein (HBx) and insulin receptor substrate 1 (IRS1) was achieved and transgenic mice were followed from birth to age 21 months. Liver and tumor tissue were assessed for histologic changes as well as activation of signal transduction pathways by qRT-PCR and multiplex ELISA protein assays. RESULTS: Overexpression of HBx and IRS1 stimulates liver cell proliferation in the double transgenic mice. Only the male mice …

Residency Program At Michael E Debakey Department Of Surgery, Baylor College Of Medicine, F Charles Brunicardi

Faculty, Staff and Students Publications

No abstract provided.

Patterns Of Fatty Acid Release From Endogenous Substrates By Human Platelet Homogenates And Membranes, A Derksen, P Cohen

Faculty, Staff and Students Publications

We describe a method for measuring the release of fatty acids from endogenous substrates of human platelet homogenates and membranes. The method depends on the availability of lipids whose fatty acids are odd-chained and therefore suitable as internal reference compounds that, at the time of lipid extraction, can be added to an incubation to permit subsequent quantification of the content of free fatty acids or fatty acids esterified to specific lipids. We found four types of lipolytic activities in human platelets. In homogenates at pH 4.0 a triglyceride lipase operated as shown by the synchrony of triglyceride degradation and release …

Atomic Models For The Polypeptide Backbones Of Myohemerythrin And Hemerythrin, W A Hendrickson, K B Ward

Faculty, Staff and Students Publications

Background: The novel coronavirus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spread rapidly after its identification in December 2019 to cause a global pandemic. The respiratory tract is the primary site of infection, and there is a large range in the severity of respiratory illnesses caused by the virus. Defining molecular and cellular factors for protection from severe disease and death has been a goal to better understand and to predict and mitigate the effects of SARS-CoV-2 and future coronaviruses.

Objective: Despite well-known susceptibilities to respiratory viral infections, respiratory allergy and allergic asthma have not been identified as risk factors …