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In JoVE (1)
Other Publications (8)
- PloS One
- Journal of Physics. Condensed Matter : an Institute of Physics Journal
- Journal of the American Society of Echocardiography : Official Publication of the American Society of Echocardiography
- Archives of Surgery (Chicago, Ill. : 1960)
- Anticancer Research
- Journal of Critical Care
- PloS One
- Journal of Molecular and Cellular Cardiology
Articles by Arpit D. Shah in JoVE
JoVE Bioengineering
Three-dimensional Cell Culture Model for Measuring the Effects of Interstitial Fluid Flow on Tumor Cell Invasion
School of Biomedical Engineering, Science and Health Systems, Drexel University
Interstitial fluid flow is elevated in solid tumors and can modulate tumor cell invasion. Here we describe a technique to apply interstitial fluid flow to cells embedded in a matrix and then measure its effects on cell invasion. This technique can be easily adapted to study other systems.
Other articles by Arpit D. Shah on PubMed
Crowd Sourcing a New Paradigm for Interactome Driven Drug Target Identification in Mycobacterium Tuberculosis
A decade since the availability of Mycobacterium tuberculosis (Mtb) genome sequence, no promising drug has seen the light of the day. This not only indicates the challenges in discovering new drugs but also suggests a gap in our current understanding of Mtb biology. We attempt to bridge this gap by carrying out extensive re-annotation and constructing a systems level protein interaction map of Mtb with an objective of finding novel drug target candidates. Towards this, we synergized crowd sourcing and social networking methods through an initiative 'Connect to Decode' (C2D) to generate the first and largest manually curated interactome of Mtb termed 'interactome pathway' (IPW), encompassing a total of 1434 proteins connected through 2575 functional relationships. Interactions leading to gene regulation, signal transduction, metabolism, structural complex formation have been catalogued. In the process, we have functionally annotated 87% of the Mtb genome in context of gene products. We further combine IPW with STRING based network to report central proteins, which may be assessed as potential drug targets for development of drugs with least possible side effects. The fact that five of the 17 predicted drug targets are already experimentally validated either genetically or biochemically lends credence to our unique approach.
Non-equilibrium Cation Distribution and Enhanced Spin Disorder in Hollow CoFe2O4 Nanoparticles
We present magnetic properties of hollow and solid CoFe(2)O(4) nanoparticles that were obtained by annealing of Co(33)Fe(67)/CoFe(2)O(4) (core/shell) nanoparticles. Hollow nanoparticles were polycrystalline whereas the solid nanoparticles were mostly single crystal. Electronic structure studies were performed by photoemission which revealed that particles with hollow morphology have a higher degree of inversion compared to solid nanoparticles and the bulk counterpart. Electronic structure and the magnetic measurements show that particles have uncompensated spins. Quantitative comparison of saturation magnetization (M(S )), assuming bulk Néel type spin structure with cationic distribution, calculated from quantitative XPS analysis, is presented. The thickness of uncompensated spins is calculated to be significantly large for particles with hollow morphology compared to solid nanoparticles. Both morphologies show a lack of saturation up to 7 T. Moreover magnetic irreversibility exists up to 7 T of cooling fields for the entire temperature range (10-300 K). These effects are due to the large bulk anisotropy constant of CoFe(2)O(4) which is the highest among the cubic spinel ferrites. The effect of the uncompensated spins for hollow nanoparticles was investigated by cooling the sample in large fields of up to 9 T. The magnitude of horizontal shift resulting from the unidirectional anisotropy was more than three times larger than that of solid nanoparticles. As an indication signature of uncompensated spin structure, 11% vertical shift for hollow nanoparticles is observed, whereas solid nanoparticles do not show a similar shift. Deconvolution of the hysteresis response recorded at 300 K reveals the presence of a significant paramagnetic component for particles with hollow morphology which further confirms enhanced spin disorder.
Right Ventricular Normal Measurements: Time to Index?
BACKGROUND: Despite the common practice of indexing left ventricular dimensions to body surface area, there remains a lack of indexed normal right ventricular (RV) two-dimensional caliper measurements. Variations in ranges for normal RV dimensions have been shown to exist, and indexing RV dimensions according to body surface area may help reduce this and provide a standardization useful for clinical practice. The aim of this study was to prospectively establish both absolute and indexed normal dimensions for the right ventricle using standardized positions in a multiethnic population. Furthermore, the effects of both gender and ethnicity on both the absolute and indexed results were also evaluated. METHODS: Two hundred five healthy volunteers from four ethnic backgrounds (Indian, Chinese, Malay, and European) were prospectively enrolled and underwent two-dimensional echocardiography according to a set protocol. Ten measurements were made in conjunction with previous research. Intraobserver and interobserver and test-retest variability was assessed using coefficients of variation and intraclass correlation coefficients. RESULTS: Male absolute results exceeded female absolute results in 90% of measurements (P = .003). European absolute results (male and female) were significantly larger in up to eight of 10 measurements (P = .01). When indexed, female results became significantly larger (P < .001) than male results. Indexing was able to reduce the number of statistical differences between male ethnic groups. Measurements showed good levels of intraobserver and interobserver variability for apical and short-axis measurements. CONCLUSIONS: Gender and body surface area play an important part in the determination of normal RV reference ranges, whereas ethnicity has little influence. Results using the suggested RV markers for these measurements showed good repeatability.
Worse Outcomes in Patients Undergoing Urgent Surgery for Left-sided Diverticulitis Admitted on Weekends Vs Weekdays: a Population-based Study of 31 832 Patients
Among patients undergoing urgent surgery for left-sided diverticulitis, those admitted on weekends vs weekdays have higher rates of Hartmann procedure and adverse outcomes.
The Role of PI3K/mTOR Inhibition in Combination with Sorafenib in Hepatocellular Carcinoma Treatment
Deregulated RAS/RAF/MAPK and PI3K/AKT/mTOR signaling pathways are found in hepatocellular carcinoma (HCC). This study aimed to test the inhibitory effects of PI-103 (a small molecule inhibitor of PI3K and mTOR) and sorafenib as single agents and in combination on HCC tumorigenesis in an in vivo xenograft model.
Nonpharmacologic Approach to Minimizing Shivering During Surface Cooling: a Proof of Principle Study
This study had 2 objectives: (1) to quantify the metabolic response to physical cooling in febrile patients with systemic inflammatory response syndrome (SIRS) and (2) to provide proof for the hypothesis that the efficiency of external cooling and the subsequent shivering response are influenced by site and temperature of surface cooling pads.
An International Reference Consensus Genetic Map with 897 Marker Loci Based on 11 Mapping Populations for Tetraploid Groundnut (Arachis Hypogaea L.)
Only a few genetic maps based on recombinant inbred line (RIL) and backcross (BC) populations have been developed for tetraploid groundnut. The marker density, however, is not very satisfactory especially in the context of large genome size (2800 Mb/1C) and 20 linkage groups (LGs). Therefore, using marker segregation data for 10 RILs and one BC population from the international groundnut community, with the help of common markers across different populations, a reference consensus genetic map has been developed. This map is comprised of 897 marker loci including 895 simple sequence repeat (SSR) and 2 cleaved amplified polymorphic sequence (CAPS) loci distributed on 20 LGs (a01-a10 and b01-b10) spanning a map distance of 3, 863.6 cM with an average map density of 4.4 cM. The highest numbers of markers (70) were integrated on a01 and the least number of markers (21) on b09. The marker density, however, was lowest (6.4 cM) on a08 and highest (2.5 cM) on a01. The reference consensus map has been divided into 20 cM long 203 BINs. These BINs carry 1 (a10_02, a10_08 and a10_09) to 20 (a10_04) loci with an average of 4 marker loci per BIN. Although the polymorphism information content (PIC) value was available for 526 markers in 190 BINs, 36 and 111 BINs have at least one marker with >0.70 and >0.50 PIC values, respectively. This information will be useful for selecting highly informative and uniformly distributed markers for developing new genetic maps, background selection and diversity analysis. Most importantly, this reference consensus map will serve as a reliable reference for aligning new genetic and physical maps, performing QTL analysis in a multi-populations design, evaluating the genetic background effect on QTL expression, and serving other genetic and molecular breeding activities in groundnut.
Matrix Production and Remodeling Capacity of Cardiomyocyte Progenitor Cells During in Vitro Differentiation
Cell-based therapy has emerged as a treatment modality for myocardial repair. Especially cardiac resident stem cells are considered a potential cell source since they are able to differentiate into cardiomyocytes and have improved heart function after injury in a preclinical model for myocardial infarction. To avoid or repair myocardial damage it is important not only to replace the lost cardiomyocytes, but also to remodel and replace the scar tissue by "healthy" extracellular matrix (ECM). Interestingly, the role of cardiac stem cells in this facet of cardiac repair is largely unknown. Therefore, we investigated the expression and production of ECM proteins, matrix metalloproteinases (MMPs) and their inhibitors (TIMPs) in human cardiomyocyte progenitor cells (CMPCs) undergoing differentiation towards the cardiomyogenic lineage. Our data suggest that CMPCs have the capacity to synthesize and modulate their own matrix environment, especially during differentiation towards the cardiomyogenic lineage. While undifferentiated CMPCs expressed collagen I, III, IV and fibronectin, but no elastin, during the process of differentiation the expression of collagen I, III, IV and fibronectin increased and interestingly also elastin expression was induced. Furthermore, undifferentiated CMPCs express MMP-1 -2 and -9 and upon differentiation the expression of MMP-1 decreased, while the expression of MMP-2 and MMP-9, although the latter only in the early stage of differentiation, increased. Additionally, the expression of TIMP-1, -2 and -4 was induced during differentiation. This study provides new insights into the matrix production and remodeling capacity of human CMPCs, with potential beneficial effects for the treatment of cardiac injury.
