University of Maryland, College Park

7 ARTICLES PUBLISHED IN JoVE

Biology

Atmospheric-pressure Molecular Imaging of Biological Tissues and Biofilms by LAESI Mass Spectrometry

¹Department of Chemistry, George Washington University

Laser ablation electrospray ionization (LAESI) is an atmospheric-pressure ion source for mass spectrometry. In the imaging mode, a mid-infrared laser probes the distributions of molecules across a tissue section or a biofilm. This technique presents a new approach for diverse bioanalytical studies carried out under native experimental conditions.

Bioengineering

Intra-lymph Node Injection of Biodegradable Polymer Particles

James I. Andorko^*1, Lisa H. Tostanoski^*1, Eduardo Solano¹, Maryam Mukhamedova¹, Christopher M. Jewell¹

¹Fischell Department of Bioengineering, University of Maryland, College Park

Lymph nodes are the immunological tissues that orchestrate immune response and are a critical target for vaccines. Biomaterials have been employed to better target lymph nodes and to control delivery of antigens or adjuvants. This paper describes a technique combining these ideas to inject biocompatible polymer particles into lymph nodes.

Behavior

The "Motor" in Implicit Motor Sequence Learning: A Foot-stepping Serial Reaction Time Task

Yue Du¹, Jane E. Clark^1,2

¹Department of Kinesiology, University of Maryland, College Park, ²The Neuroscience and Cognitive Science Program, University of Maryland, College Park

We introduce the foot-stepping serial reaction time (SRT) task. This modified SRT task, complementing the classic SRT task that involves only finger-pressing movement, better approximates daily sequenced activities and allows researchers to study the dynamic processes underlying discrete response measures and disentangle the explicit process operating in implicit sequence learning.

Chemistry

Microprobe Capillary Electrophoresis Mass Spectrometry for Single-cell Metabolomics in Live Frog (Xenopus laevis) Embryos

Rosemary M. Onjiko¹, Erika P. Portero¹, Sally A. Moody², Peter Nemes^1,3

¹Department of Chemistry, George Washington University, ²Department of Anatomy & Regenerative Biology, George Washington University, ³Department of Chemistry & Biochemistry, University of Maryland, College Park

We describe steps that enable fast in situ sampling of a small portion of an individual cell with high precision and minimal invasion using capillary-based micro-sampling, to facilitate chemical characterization of a snapshot of metabolic activity in live embryos using a custom-built single cell capillary electrophoresis and mass spectrometry platform.

Developmental Biology

Development of Targeting Induced Local Lesions IN Genomes (TILLING) Populations in Small Grain Crops by Ethyl Methanesulfonate Mutagenesis

Lovepreet Singh¹, Adam Schoen¹, Alexander Mahlandt¹, Bhavit Chhabra¹, James Steadham¹, Vijay Tiwari¹, Nidhi Rawat¹

¹Department of Plant Science and Landscape Architecture, University of Maryland, College Park

Described is a protocol for developing a Targeting Induced Local Lesions IN Genomes (TILLING) population in small grain crops with use of ethyl methanesulfonate (EMS) as a mutagen. Also provided is a protocol for mutation detection using the Cel-1 assay.

Developmental Biology

In Ovo Intravascular Injection in Chicken Embryos

Kai Jin^1,2, Jing Zhou^1,2, Gaoyuan Wu^1,2, Ziyi Lian^1,2, Zongyi Zhao^1,2, Shujian Zhou^1,2, Chen Chen^1,2, Hongyan Sun^1,2, Yingjie Niu^1,2, Qishenng Zuo^1,2, Yani Zhang^1,2, Jiuzhou Song³, Guohong Chen^1,2, Bichun Li^1,2,4

¹Joint International Research Laboratory of Agriculture and Agri-Product Safety of Ministry of Education of China, Yangzhou University, ²Key Laboratory of Animal Breeding Reproduction and Molecular Design for Jiangsu Province, College of Animal Science and Technology, Yangzhou University, ³Animal & Avian Sciences, University of Maryland, College Park, ⁴College of Biotechnology, Jiangsu University of Science and Technology

The overall goal of this paper is to describe how to perform in ovo intracellular injection of exogenous materials into chicken embryos. This approach is very useful to study the developmental biology of chicken embryos.

Chemistry

Cell-Lineage Guided Mass Spectrometry Proteomics in the Developing (Frog) Embryo

Aparna B. Baxi^1,2, Leena R. Pade¹, Peter Nemes^1,2

¹Department of Chemistry & Biochemistry, University of Maryland, ²Department of Anatomy & Cell Biology, The George Washington University

Here we describe a mass spectrometry-based proteomic characterization of cell lineages with known tissue fates in the vertebrate Xenopus laevis embryo.