Arkansas Children’s Nutrition Center is housed in a state-of-the-art facility on the campus of Arkansas Children’s Hospital in Little Rock, Arkansas. With an $17.1 million expansion that was completed in 2005, the Center now boasts approximately 54,000 square feet of space which includes 14 lab areas, a Family Living Center with a six bed live-in research unit, a large outpatient unit, multiple brain function laboratories and a nutritional assessment laboratory. Our facility, adjacent to Arkansas Children’s Hospital Research Institute, provides us access to cutting-edge research being done in all fields of pediatrics. We are also located only one mile from the state’s only medical school, the University of Arkansas for Medical Sciences, meaning our researchers act as scientists and teachers on a daily basis.
The Human Studies Facility (HSF) was established in 1998 to support all activities necessary for Clinical Studies. The clinical space includes a living center, four clinic rooms, six private bedrooms and bathrooms that may be used for overnight studies, a large common area with a television, a toddler play room and a dining room. The HSF is overseen by Dr. Thomas Badger and consists of 4 main elements:
1) Study Recruitment and Coordination
The study recruitment and coordination core is a major component of our Human Studies Facility. The study recruitment and coordination core assists principal investigators and scientists in the day-to-day operation of clinical studies. Andrea Stokes, our Clinical Research Promoter, directs all clinical study recruitment and retention activities and also manages the promotion of Arkansas Children’s Nutrition Center within our community. Kerry Wood, our Nutrition Studies Coordinator, coordinates all clinical studies by ensuring that all study protocols are performed according to local, state and federal regulations and by verifying the collection of high quality data.
2) Nutrition, Body Composition and Physical Activity
This core is directed by Dr. Aline Andres and works to accurately assess dietary intake, body composition and physical activity in humans from birth to adulthood. Nutrition assessment is obtained via Food Frequency Questionnaires completed by study participants. Data is entered into the Nutrition Data System for Research, a dietary analysis program designed for the collection and analyses of 24-hour dietary recalls and the analysis of food records, menus, and recipes. Body composition is evaluated via several methods: anthropometrics, dual-energy x-ray absorptiometry, air displacement plethysmography, bioelectrical impedance and nuclear magnetic resonance analyzation. Arkansas Children’s Nutrition Center was the first facility in the world to obtain a PeaPod air displacement plethysmography device and one of the first institutions to get an EchoMRI-AHTM nuclear magnetic resonance device capable of measuring whole body fat mass, whole body lean mass and whole body free fluids in 2-50 kg participants. Physical activity is currently evaluated using standardized and validated questionnaires, pedometers, and tri-axial accelerometers for use in the pediatric and adult population.
3) Brain Function
The Brain Function core is directed by Dr. Terry Pivik. It has the responsibility of conducting studies that clarify the role of dietary intake, physical activity and body composition on developmental processes. This is accomplished through the identification of indicators of physiological functions and performance in infants and children. The Brain Function core relates measures of behavioral development and body and brain activities to nutritional variables (for example, diet type, meal frequency and amounts) and cognitive processes (such as attention, language development and thinking processes involved in the selection and responses to visual and auditory information). The measures used are standardized and all are non-invasive. The goal of these studies is to better define dietary factors, physical activity and body composition that will maximize healthy development and behavior.
4) Psychology
This core is established to serve as a complement to the Brain Function Core in the investigation of the effect of dietary intake, physical activity and body composition on brain function and development by the use of standardized psychological assessments. Trained psychological examiners and technicians objectively assess participants by administering standardized assessments that elicit a broad spectrum of responses and observable behaviors from infants, children and adults. Evaluations are completed with study participants using combinations of over forty neuropsychological and behavioral assessments tailored to particular areas of emphasis. Specific areas of study include language development, visual-spatial processing, visual-motor integration, motor development, executive functions, intelligence, memory, temperament, personality, mood and behavior. Other assessments may be completed by participants to gain their perceptions and insight through self-report. Many other assessments are completed by caregivers to obtain information about their children’s behavior and emotions in different environments.
The Animal Research Facility (ARF) at Arkansas Children’s Nutrition Center is directed by Dr. Thomas Badger and conducts all studies involving live animals. The ARF consists of a team of highly trained technical staff which includes 7 full-time animal care personnel in addition to the Director. The facility is part of a new state-of-the-art AAALAC approved animal facility at Arkansas Children’s Hospital Research Institute. The ACHRI animal facility has a staff of 10 individuals including board certified veterinarians, an animal facility manager and animal care personnel who work in close conjunction with the ARF team in conducting basic animal husbandry services. All aspects of executing animal experiments, however, are carried out by ARF staff, including starting IACUC protocols, tracking animals (using subcutaneous microchips, eartags, etc.), surgical manipulations, performing serial in vivo assessments (e.g., body composition, indirect calorimetry, insulin clamp studies, oral glucose tolerance tests, and peripheral quantitative computerized tomography) and collection and banking of tissues. Surgical manipulations such as intragastric and intravenously cannulations, implantations of infusions pumps, and surgical resections of ovaries, pituitaries, liver, etc. are also regularly carried out by ARF staff. The ARF also has facilities assessment of whole animal body composition using X-ray computerized tomography, nuclear magnetic resonance and dual x-ray absortiometry. Specific analyses of bone mineral density, content and other skeletal parameters can be carried out in live animals (rodents) or ex vivo (in rodents and pigs) using pQCT within the ARF. Facilities to assess blood pressure using a tail-cuff in rats are also available and routinely employed by investigators. In addition, a separate insulin-clamp lab is available for investigators to perform experiments under euglycemic or hyperglycemic conditions. The ARF is also equipped with a Comprehensive Laboratory Animal Monitoring System (CLAMS) to perform 24-hour metabolic assessments of food and water-intake, indirect calorimetry and activity measurements. These assessments can be carried out in rats and mice. The ARF conducts experiments with rodents and other large animals such as pigs. Separate barrier housing for transgenic and knockout mice are also available. Data recording and archiving are performed according to standardized protocols developed by the ARF and all data are maintained through databases specifically designed to meet particular needs of each animal study.
The ACNC Genomics and Bioinformatics Facility, a designated Affymetrix core facility, is equipped with an Affymetrix GeneChip Fluidics 450 platform, hybridization oven, GeneChip 3000 scanner and Dell Optiplex PC workstation with Affymetrix Command Console Software. In addition, other instrumentation required to perform all the steps of microarray analyses from RNA extraction, purification, quality control analyses, cDNA synthesis, cRNA synthesis, labeling, hybridization and washing are part of the ACNC Genomics and Bioinformatics facility. These include, polytron homogenizers, refrigerated table-top centrifuges, Agilent 2100 Bioanalyzer, BioRad Smartspec plus, BioRad Experion automated electrophoresis station, Nano Drop ND-1000, spectrophomoters, thermal cyclers, PCR hoods, heat-blocks, incubators, etc. Dedicated computers are available for data analyses and bioinformatics of microarray data. Centralized access and training for GeneSpring GX (Agilent technologies), GCOS, Ingenuity Pathway Analyses, Pathway Studio, Cluster, TreeView, GenMapp, MS Excel and other software are available through the facility. The ACNC Genomics and Bioinformatics facility is state-of-the-art and is capable of examining whole genome expression (human, rat, mouse, porcine, etc.) arrays and newly emerging technologies such as ChIP-on-chip, methylation arrays and tiling arrays.
The Biochemistry Core is overseen by Dr. Martin Ronis. The Core has experienced staff who conduct routine biochemical and endocrine analyses as a service to the rest of the ACNC. The Biochemistry Core is responsible for conduct of enzyme assays for phase I and II metabolism of drugs, carcinogens and steroids using spectrophometric, spectrofluorimetric, TLC, GC-MS, HPLC and radio-HPLC assays. Substrate-specific assays for all the major cytochrome P450 enzymes, sulfotransferases, GSTs and UDPGTs are standardized. Routine analysis of protein content, intermediary metabolism, lipid peroxidation and GSH/GSSG are conducted by spectrophometric assays and by HPLC-utilizing electrochemical and photoarray detection. Metal analysis is conducted using atomic absorption spectroscopy. The Core runs quantitative Western immunoblot analysis for enzymes, transcription factors and other cellular proteins using antisera obtained from collaborators and commercially available antibodies and characterizes peptide-specific antisera made under subcontract. The Biochemical Core conducts routine analysis of hormones and cytokines by radioimmunoassay and ELISA using commercially available kits and NIH supplied reagents for such hormones as GH and LH. In addition, protein purification of enzymes and transcription factors is conducted by the Biochemistry Core.
The laboratories are equipped with two Shimadzu scanning Spectrophotometers, a scanning Spectrofluorimeter, HPLC systems with auto-samplers and MS, UV, Photodiode Array, Coularray and radioisotope detectors. In addition, there is a GC with flame and electrochemical detector and a GC-MS with both head space and liquid auto-samplers. SDS-PAGE apparatus are available in MiniGel, medium and large sizes and there is a bench top X-ray film developer. In addition the ACNC possesses a BioRad Molecular Phosphoimager and Densitometer capable of quantitative densitometric analysis of X-ray film, direct phosphoimaging of 32P, 35S, 14C and 3H signals on gels, nitrocellulose filters and TLC plates and chemiluminescence. There is also a Shimadzu Atomic Absorption Spectrometer for analysis of metal ions, a gamma counter for quantification of radioimmunoassays and an FPLC protein purification system.
The Cell Culture and Immunology facility is overseen by Dr. Shanmugam Nagarajan. The facility houses 14 CO2 incubators, 5 NuAire laminar airflow hoods, a Nikon TMS microscope and a Ziess Invertoscope. The facility also has a centralized cryostorage repository for storage and archiving of cell culture stocks. The facility offers introduction, handling, propagation and maintenance of various cell cultures. In addition, the facility has a BioRad Genepulser II and an Amaxa Nucleaofector II for electroporation of exogenous plasmid vectors or siRNA into specific cell lines. The facility also has a BD FACS Calibur flow cyometer and cell sorter for quantitative assessments of different cell populations. Assays for cell proliferation, apoptosis, viability, oxidative stress and presence/absence of cell surface antigens are routinely performed on this instrument. In addition, the Immunology facility has a BioPlex multiplex bead array system. The Bio-Plex system utilizes Luminex xMAP technology which permits the multiplexing of up to 100 different assays within a single sample.
The Histology and Bio-imaging Facility assists in the routine processing of tissues from experimental studies for histological and immunohistochemical analyses. The facility has an automated Sakura Tissue Tek Vacuum Infiltration Processor for processing tissues and a Tissue Tek Embedding platform. The facility also has a Leica RM2135 microtome for cutting paraffin or acrylic embedded blocks. The laboratory utilizes a Microm HM 550 cryostat for performing analyses on frozen sections. The facility has standardized protocols for histochemical and immunohistochemical staining that can be done manually or performed using an automated Dako autostainer. The facility is overseen by Dr. Rosalia C. M. Simmen and is staffed with certified histo-technicians. Another function of the facility is to fulfill the bio-imaging and image analysis needs of the investigators. The facility has an Olympus BX50 upright microscope and a Nikon SM2800 sterioscope fitted with a Sony DXC970MD 3-CCD camera. This workstation is also equipped with a Dell Precision computer with MCID Elite software. The MCID Elite software is complete with histomorphometry capabilities, density scanning and 3-dimensional reconstruction and rendering capabilities. In addition, the facility has an Olympus IX71 inverted fluorescence microscope equipped with Osteomeasure software. This system is set-up to perform both static and dynamic histomorphometric analyses of skeletal samples. Further, light and fluorescence imaging needs of investigators are met using the Zeiss Axiovert 200M inverted microscope. This microscope has a motorized stage, z-stack capabilities, and can read DAPI, Alexa 488 and Rhodamine dyes. It is also equipped with AxioVision software which is capable of complex histomorphometric analyses on acquired images and can be used on entire batches of images. The Histology facility also has general laboratory equipment necessary for effective functioning including slide warmers, ovens and incubators dedicated for histological procedures. The facility acts as an important resource for training, supervision and development of new immunohistochemical procedures.
The Molecular Biology Facility at Arkansas Children’s Nutrition Center caters to the needs of ACNC investigators with the mission of providing cutting-edge molecular techniques in addressing specific experimental issues. The facility is overseen by Dr. Frank A. Simmen. The facility, as a whole, works closely with each investigator and also, at times, integrates the expertise of other centralized facilities in the ACNC such as the Cell Culture facility and the Microscopy Facility. The Molecular Biology facility offers a multitude of specific services and technical expertise and training in a variety of techniques. Some examples include gene expression analyses and cloning of genes of interest into expression vectors for either stable or transient expression in mammalian cell culture. This core is especially well set-up for studies of nutritional and developmental regulation of gene expression, pathway analysis, and gene expression profiling during various physiological and pathological states.
The facility also houses two real-time RT-PCR instruments (iCycler, BioRad labs and Agilent Prism 7000 Sequence Detection System) for gene expression analyses. In addition, the facility assists investigators in primer design (using Primer Express software, Agilent technologies) for regular PCR or real-time RT-PCR, and primer design for other PCR applications such as cloning or regulatory sequences of genes. The molecular biology facility also has four thermal cyclers (two ABI GeneAmp 2700, one ABI GeneAmp 9700 and one Eppendorf Mastercycler) for PCR applications. The molecular biology facility also is outfitted with necessary equipment to perform gene expression analyses using Northern blots, RNAse protection assays, in vitro transcription and nuclear run-on assays. Dedicated apparatus and bench-space are available for use of radioactive isotopes (α or γ-32P or 33P-nucleotides). In addition, the laboratory facilitates assessment of DNA using Southern blot, and protein-DNA interaction using electro-mobility shift assays. The molecular biology facility also assists in performing luciferase-based reporter assays using the MLX Microtiter Plate Luminometer. Equipment to perform immunoblotting is available. Further, the facility has a BioRad Chemidoc XRS, BioRad GelDoc 1000, GS-700 Imaging densitometer, ImageScanner III, Benchmark microplate photometer, Personal Fx molecular phosphorimager and Kodak SRX-100 automated film developer, along with several data acquisition and analyses software.
