42 results on '"Sunny S. Shah"'
Search Results
2. Answer Ranking in Community Question Answer (QA) System and Questions Recommendation
- Author
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Akash S. Kalyankar, Tejas S. Bavaskar, Sunny S. Shah, Rahul Patil, and Sourabh S. Ukhale
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Questions and answers ,World Wide Web ,Computer science ,0202 electrical engineering, electronic engineering, information engineering ,Collaborative filtering ,Redundancy (engineering) ,A domain ,Pairwise ranking ,020206 networking & telecommunications ,020201 artificial intelligence & image processing ,02 engineering and technology ,Question answer ,Levenshtein distance - Abstract
There are many question-answer forum but still when a user wants an answer to his/her question, posting it on the forum or manually searching the answer on the forum is a tedious task. Also, when it comes to searching for the answer that a user wants, make it even more difficult. On top of that, every other person can form the similar meaning question differently and if that question isn't present in the forum it will add it and may create redundancy in the database and also on the forum. So, our proposed system which not only will remove the redundancy of the similar meaning question but also will rank the answer based on like and comments. We also added various features like bookmark the answer a user likes and also send those question and answer to the user via e-mail. Above all, we are also helping the user to get a recommendation based on the user activity. The system is a domain specific. So, we will be using three domain of 1. Programming Languages 2. Higher Studies 3. In-Car Assistance for the question-answer forum and the date i.e. questions and answers to them will be created dynamically.
- Published
- 2018
3. Current Technologies and Recent Developments for Screening of HPV-Associated Cervical and Oropharyngeal Cancers
- Author
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Sunny S. Shah, Flora Klacsmann, Jeffrey J. Johnson, Hsueh-Chia Chang, Satyajyoti Senapati, Daniel Miller, and M. Stack
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0301 basic medicine ,Oncology ,Cancer Research ,medicine.medical_specialty ,Review ,Biology ,lcsh:RC254-282 ,Virus ,03 medical and health sciences ,Internal medicine ,Cancer screening ,medicine ,diagnostics ,human papillomavirus ,HPV DNA ,Cervical cancer ,microRNA ,HPV infection ,Cancer ,integrated platform ,medicine.disease ,lcsh:Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,3. Good health ,Mucosal Infection ,E6/E7 genotypes ,Vaccination ,Hpv testing ,030104 developmental biology ,Immunology ,cervical and oropharyngeal cancers - Abstract
Mucosal infection by the human papillomavirus (HPV) is responsible for a growing number of malignancies, predominantly represented by cervical cancer and oropharyngeal squamous cell carcinoma. Because of the prevalence of the virus, persistence of infection, and long latency period, novel and low-cost methods are needed for effective population level screening and monitoring. We review established methods for screening of cervical and oral cancer as well as commercially-available techniques for detection of HPV DNA. We then describe the ongoing development of microfluidic nucleic acid-based biosensors to evaluate circulating host microRNAs that are produced in response to an oncogenic HPV infection. The goal is to develop an ideal screening platform that is low-cost, portable, and easy to use, with appropriate signal stability, sensitivity and specificity. Advances in technologies for sample lysis, pre-treatment and concentration, and multiplexed nucleic acid detection are provided. Continued development of these devices provides opportunities for cancer screening in low resource settings, for point-of-care diagnostics and self-screening, and for monitoring response to vaccination or surgical treatment.
- Published
- 2016
4. Characterization and quantification of nanoparticle–antibody conjugates on cells using C60 ToF SIMS in the event-by-event bombardment/detection mode
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Michael J. Eller, Emile A. Schweikert, Alexander Revzin, Jaime Silangcruz, Li Jung Chen, Stanislav V. Verkhoturov, and Sunny S. Shah
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Chemistry ,Analytical chemistry ,Nanoparticle ,Condensed Matter Physics ,Article ,Ion ,Secondary ion mass spectrometry ,Membrane ,Mass spectrum ,Physical and Theoretical Chemistry ,Lipid bilayer ,Instrumentation ,Spectroscopy ,Cysteine ,Conjugate - Abstract
Cluster C 60 ToF-SIMS (time-of-flight secondary ion mass spectrometry) operated in the event-by-event bombardment-detection method has been applied to: (a) quantify the binding density of Au nanoparticles (AuNPs)–antiCD4 conjugates on the cell surface and (b) identify the binding sites between AuNPs and antibody. Briefly, our method consists of recording the secondary ions, SIs, individually emitted from a single C 60 1,2+ impact. From the cumulative mass spectral data we selected events where a specific SI was detected. The selected records revealed the SIs co-ejected from the nanovolume impacted by an individual C 60 with an emission area of ∼10 nm in diameter as an emission depth of 5–10 nm. The fractional coverage is obtained as the ratio of the effective number of projectile impacts on a specified sampling area ( N e ) to the total number of impacts ( N o ). In the negative ion mass spectrum, the palmitate (C 16 H 31 O 2 − ) and oletate (C 18 H 33 O 2 − ) fatty acid ions present signals from lipid membrane of the cells. The signals at m / z 197 (Au − ) and 223 (AuCN − ) originate from the AuNPs labeled antibodies (antiCD4) bound to the cell surface antigens. The characteristic amino acid ions validate the presence of antiCD4. A coincidence mass spectrum extracted with ion at m / z 223 (AuCN − ) reveals the presence of cysteine at m / z 120, documenting the closeness of cysteine and the AuNP. Their proximity suggests that the binding site for AuNP on the antibody is the sulfur-terminal cysteine. The fractional coverage of membrane lipid was determined to be ∼23% of the cell surfaces while the AuNPs was found to be ∼21%. The novel method can be implemented on smaller size NPs, it should thus be applicable for studies on size dependent binding of NP–antibody conjugates.
- Published
- 2011
5. Micropatterning of bioactive heparin-based hydrogels
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Giyoong Tae, Katelyn Cahill-Thompson, Alexander Revzin, Mihye Kim, and Sunny S. Shah
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Chemistry ,Kinetics ,technology, industry, and agriculture ,macromolecular substances ,General Chemistry ,Heparin ,Condensed Matter Physics ,complex mixtures ,In vitro ,In vivo ,PEG ratio ,Self-healing hydrogels ,Polymer chemistry ,Biophysics ,medicine ,Prepolymer ,Micropatterning ,medicine.drug - Abstract
This paper describes a UV photopatterning of bioactive heparin-based hydrogels on glass substrates. In this approach, hydrogel micropatterns were formed by UV-initiated thiol–ene reaction between thiolated heparin and diacrylated poly(ethylene) glycol (PEG-DA). Analysis of gelation kinetics showed that photo-crosslinked hydrogels formed faster and were stronger when compared to hydrogels formed by competing Michael addition reaction. To highlight bioactivity of heparin–PEG hybrid gels, hepatocyte growth factor (HGF) was mixed into prepolymer solution prior to hydrogel patterning. Immunostaining showed that HGF was retained after 5 days in the hybrid heparin–PEG hydrogel microstructures but was rapidly released from pure PEG gel microstructures. In a set of experiments further highlighting bioactivity of microfabricated heparin-based hydrogel, primary rat hepatocytes were cultured next to heparin and pure PEG hydrogel disks (∼500 µm in diameter). ELISA analysis revealed that hepatocytes residing next to heparin-based hydrogels were producing ∼4 times more albumin at day 7 compared to cells cultured next to inert PEG hydrogels. In the future, microfabricated heparin-based hydrogels described in this paper will be employed for designing cellular microenvironment in vitro and as vehicles for cell transplantation in vivo.
- Published
- 2011
6. Characterization and quantification of biological micropatterns using cluster SIMS
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Emile A. Schweikert, Alexander Revzin, Sunny S. Shah, Li Jung Chen, and Stanislav V. Verkhoturov
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Nanotechnology ,Surfaces and Interfaces ,General Chemistry ,Photoresist ,Condensed Matter Physics ,Surfaces, Coatings and Films ,Characterization (materials science) ,Indium tin oxide ,Secondary ion mass spectrometry ,chemistry.chemical_compound ,chemistry ,Materials Chemistry ,Self-assembly ,Biosensor ,Ethylene glycol ,Micropatterning - Abstract
Micropatterning is used widely in biosensor development, tissue engineering and basic biology. Creation of biological micropatterns typically involves multiple sequential steps which may lead to cross-contamination and contribute to suboptimal performance of the surface. Therefore, there is a need to develop novel strategies for characterizing location-specific chemical composition of biological micropatterns. In this paper, C 60 + time-of-flight secondary ion mass spectrometry (ToF-SIMS) operating in the event-by-event bombardment/detection mode was used for spatially resolved chemical analysis of micropatterned indium tin oxide (ITO) surfaces. Fabrication of the micropatterns involved multiple steps including self-assembly of poly(ethylene glycol)-silane (PEG-silane), patterning of photoresist, treatment with oxygen plasma and adsorption of collagen (I). The ITO surfaces were analyzed with 26-keV C 60 + SIMS run in the event-by-event bombardment/detection mode at different steps of the modification process. We were able to evaluate the extent of cross-contamination between different steps and quantify coverage of the immobilized species. The methodology described here provides a novel means for characterizing the composition of biological micropatterns in a quantitative and spatially resolved manner.
- Published
- 2010
7. Micropatterning of Proteins and Mammalian Cells on Indium Tin Oxide
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Jaime Silangcruz, Sunny S. Shah, Li Jung Chen, Atul N. Parikh, Emile A. Schweikert, Stanislav V. Verkhoturov, Michael C. Howland, and Alexander Revzin
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Materials science ,Surface Properties ,Nanotechnology ,Photoresist ,Surface engineering ,Microscopy, Atomic Force ,Article ,Mass Spectrometry ,Polyethylene Glycols ,Mice ,chemistry.chemical_compound ,PEG ratio ,Animals ,Humans ,General Materials Science ,Tin Compounds ,Substrate (chemistry) ,3T3 Cells ,Electrochemical Techniques ,Hep G2 Cells ,Fibroblasts ,Silanes ,Silane ,Coculture Techniques ,Rats ,Indium tin oxide ,Oxygen ,Chemical engineering ,chemistry ,Rats, Inbred Lew ,Hepatocytes ,Adsorption ,Collagen ,Layer (electronics) ,Micropatterning - Abstract
This paper describes a novel surface engineering approach that combines oxygen plasma treatment and electrochemical activation to create micropatterned cocultures on indium tin oxide (ITO) substrates. In this approach, photoresist was patterned onto an ITO substrate modified with poly(ethylene) glycol (PEG) silane. The photoresist served as a stencil during exposure of the surface to oxygen plasma. Upon incubation with collagen (I) solution and removal of the photoresist, the ITO substrate contained collagen regions surrounded by nonfouling PEG silane. Chemical analysis carried out with time-of-flight secondary ion mass spectrometry (ToF-SIMS) at different stages in micropatterned construction verified removal of PEG-silane during oxygen plasma and presence of collagen and PEG molecules on the same surface. Imaging ellipsometry and atomic force microscopy (AFM) were employed to further investigate micropatterned ITO surfaces. Biological application of this micropatterning strategy was demonstrated through selective attachment of mammalian cells on the ITO substrate. Importantly, after seeding the first cell type, the ITO surfaces could be activated by applying negative voltage (-1.4 V vs Ag/AgCl). This resulted in removal of nonfouling PEG layer and allowed to attach another cell type onto the same surface and to create micropatterned cocultures. Micropatterned cocultures of primary hepatocytes and fibroblasts created by this strategy remained functional after 9 days as verified by analysis of hepatic albumin. The novel surface engineering strategy described here may be used to pattern multiple cell types on an optically transparent and conductive substrate and is envisioned to have applications in tissue engineering and biosensing.
- Published
- 2009
8. Integrating Sensing Hydrogel Microstructures into Micropatterned Hepatocellular Cocultures
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Tingrui Pan, Sunny S. Shah, Alexander Revzin, Michael C. Howland, Atul N. Parikh, Ji Youn Lee, and Jun Yan
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Carcinoma, Hepatocellular ,Surface Properties ,Cell Culture Techniques ,Nanotechnology ,macromolecular substances ,Photoresist ,Hydrogel, Polyethylene Glycol Dimethacrylate ,Article ,Polyethylene Glycols ,law.invention ,Mice ,chemistry.chemical_compound ,law ,PEG ratio ,Electrochemistry ,Animals ,General Materials Science ,Spectroscopy ,Liver Neoplasms ,technology, industry, and agriculture ,Substrate (chemistry) ,Hydrogels ,3T3 Cells ,Surfaces and Interfaces ,Adhesion ,Fibroblasts ,Silanes ,Condensed Matter Physics ,Protein Structure, Tertiary ,chemistry ,Self-healing hydrogels ,Hepatocytes ,Biophysics ,Collagen ,Photolithography ,Biosensor ,Ethylene glycol ,Signal Transduction - Abstract
This paper describes a microfabrication-derived approach for defining interactions between distinct groups of cells and integrating biosensors with cellular micropatterns. In this approach, photoresist lithography was employed to micropattern cells adhesive ligand (collagen (I)) on silane-modified glass substrates. Poly(ethylene glycol) (PEG) photolithography was then used to fabricate hydrogel microstructures in registration with existing collagen (I) domains. A glass substrate modified in this manner had three types of micrpatterned regions: cell-adhesive collagen (I) domains, moderately adhesive silanized glass regions and non-adhesive PEG hydrogel regions. Incubation of this substrate with primary rat hepatocytes or HepG2 cells resulted in attachment of hepatic cells on collagen (I) domains with no adhesion observed on silane-modified glass regions or hydrogel domains. 3T3 fibroblasts added onto the same surface attached on the glass regions around the hepatocytes, completing the co-culture. Significantly, PEG hydrogel microstructures remained free of cells and were used to “fence” hepatocytes from fibroblasts, thus limiting communication between the cell types. We also demonstrated that entrapment of enzyme molecules inside hydrogel microstructures did not compromise non-fouling properties of PEG. Building on this result, horse radish peroxidase (HRP)-containing hydrogel microstructures were integrated into micropatterned co-cultures and were used to detect hydrogen peroxide in the culture medium. The surface micropatterning approach described here may be used in the future to simultaneously define and detect endocrine signaling between two distinct cell types.
- Published
- 2009
9. Designing Electroactive Biointerface for Spatiotemporal Control of Cell Attachment and Release
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Alexander Revzin, Jun Yan, Sunny S. Shah, Stanislav V. Verkhoturov, and He Zhu
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Microelectrode ,chemistry.chemical_compound ,Materials science ,Chemical engineering ,chemistry ,Desorption ,Electrode ,Substrate (chemistry) ,Biointerface ,Nanotechnology ,Electrochemistry ,Ethylene glycol ,Indium tin oxide - Abstract
In this paper, we demonstrate the use of individually addressable microelectrodes for cell sorting and cell micropatterning applications. Microelectrodes were modified with cell adhesive or non-adhesive molecules and then electrically stimulated to selectively adsorb or desorb proteins and/or mammalian cells. The switching of the surface properties was achieved by the electrochemical desorption of protein-functionalized thiols and poly(ethylene glycol) PEG silane from gold and indium tin oxide (ITO) electrodes respectively. The thiol surfaces were modified with anti-CD4 antibodies and used to capture T-cells. Upon electrical activation of the microelectrodes, both the antibodies and the T-cells were removed from the specific locations on the substrate. In addition, ITO electrodes were modified with cell- resistive PEG silane which was later electrochemically desorbed to make the surface adhesive to proteins or cells. This technique was employed to pattern two different cell types on the same substrate.
- Published
- 2008
10. Exercising Spatiotemporal Control of Cell Attachment with Optically Transparent Microelectrodes
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Sunny S. Shah, Alexander Revzin, Emile A. Schweikert, Stanislav V. Verkhoturov, Ji Youn Lee, Nazgul Tuleuova, and Erlan Ramanculov
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Molecular Structure ,Inorganic chemistry ,Cell Culture Techniques ,Surfaces and Interfaces ,Condensed Matter Physics ,Silane ,Mass Spectrometry ,Article ,Indium tin oxide ,chemistry.chemical_compound ,Microelectrode ,Potassium ferricyanide ,Electron transfer ,chemistry ,Chemical engineering ,Cell Line, Tumor ,Electrode ,Cell Adhesion ,Electrochemistry ,Humans ,General Materials Science ,Ferricyanide ,Cyclic voltammetry ,Microelectrodes ,Spectroscopy - Abstract
This paper describes a novel approach of controlling cell-surface interactions through an electrochemical “switching” of biointerfacial properties of optically transparent microelectrodes. The indium tin oxide (ITO) microelectrodes, fabricated on glass substrates, were modified with poly(ethylene glycol) (PEG) silane to make glass and ITO regions resistant to protein and cell adhesion. Cyclic voltammetry, with potassium ferricyanide serving as a redox reporter molecule, was used to monitor electron transfer across the electrolyte–ITO interface. PEG silane modification of ITO correlated with diminished electron transfer, judged by the disappearance of ferricyanide redox activity. Importantly, application of reductive potential (−1.4 V vs Ag/AgCl reference) corresponded with reappearance of typical ferricyanide redox peaks, thus pointing to desorption of an insulating PEG silane layer. Time-of-flight secondary ion mass spectrometry (ToF-SIMS) characterization of the silanized ITO surfaces after electrical stimulation indicated complete removal of the silane layer. Significantly, electrical stimulation allowed to “switch” chosen electrodes from nonfouling to protein-adhesive while leaving other ITO and glass regions protected by a nonfouling PEG silane layer. The spatial and temporal control of biointerfacial properties afforded by our approach was utilized to micropattern proteins and cells and to construct micropatterned co-cultures. In the future, control of the biointerfacial properties afforded by this novel approach may allow the organization of multiple cell types into precise geometric configurations in order to create better in vitro mimics of cellular complexity of the native tissues.
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- 2008
11. Integrated, DC voltage-driven nucleic acid diagnostic platform for real sample analysis: detection of oral cancer
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Hsueh-Chia Chang, Zdenek Slouka, Zonggao Shi, Satyajyoti Senapati, M. Sharon Stack, Sunny S. Shah, and Robin Lawler
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Mouth neoplasm ,Analyte ,Chemistry ,Microfluidics ,Electric Conductivity ,Nanotechnology ,Chip ,Sample (graphics) ,Article ,Analytical Chemistry ,Systems Integration ,Electrokinetic phenomena ,MicroRNAs ,Lab-On-A-Chip Devices ,Nucleic acid ,Biomarkers, Tumor ,Ion-exchange membranes ,Mouth Neoplasms - Abstract
We present an integrated and low-cost microfluidic platform capable of extraction of nucleic acids from real biological samples. We demonstrate the application of this platform in pathogen detection and cancer screening. The integrated platform consists of three units including a pretreatment unit for separation of nucleic acids from lysates, a preconcentration unit for concentration of isolated nucleic acids and a sensing unit localized at a designated position on the chip for specific detection of the target nucleic acid. The platform is based on various electrokinetic phenomena exhibited by ion exchange membranes in a DC electrical field that allow them to serve as molecular filters, analyte preconcentrators and sensors. In this manuscript, we describe each unit of the integrated chip separately and show specific detection of a microRNA (miRNA 146a) biomarker associated with oral cancer as a proof-of-concept experiment. This platform technology can easily be extended to other targets of interest by optimizing the properties of the ion exchange membranes and the specific probes functionalized onto the sensors.
- Published
- 2015
12. An Ion-Exchange Nanomembrane Sensor for Detection of Nucleic Acids using a Surface Charge Inversion Phenomenon
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Zonggao Shi, David W. Severson, Satyajyoti Senapati, Hsueh-Chia Chang, M. Sharon Stack, Sunny S. Shah, Zdenek Slouka, and Susanta K. Behura
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Conductometry ,DNA Mutational Analysis ,Molecular Sequence Data ,Static Electricity ,Biomedical Engineering ,Biophysics ,Analytical chemistry ,Biosensing Techniques ,Sensitivity and Specificity ,Article ,Ion ,Nanopores ,Nucleic Acids ,Electrochemistry ,Molecule ,Nanotechnology ,Surface charge ,Ion exchange ,Base Sequence ,Chemistry ,Reproducibility of Results ,Ion current ,Membranes, Artificial ,General Medicine ,DNA ,Equipment Design ,Sequence Analysis, DNA ,Chromatography, Ion Exchange ,Equipment Failure Analysis ,Membrane ,Nucleic acid ,Biosensor ,Biotechnology - Abstract
We present a novel low-cost biosensor for rapid, sensitive and selective detection of nucleic acids based on an ionic diode feature of an anion exchange nanoporous membrane under DC bias. The ionic diode feature is associated with external surface charge inversion on the positively charged anion exchange nanomembrane upon hybridization of negatively charged nucleic acid molecules to single-stranded oligoprobes functionalized on the membrane surface resulting in the formation of a cation selective monolayer. The resulting bipolar membrane causes a transition from electroconvection-controlled to water-splitting controlled ion conductance, with a large ion current signature that can be used to accurately quantify the hybridized nucleic acids. The platform is capable of distinguishing two base-pair mismatches in a 22-base pairing segment of microRNAs associated with oral cancer, as well as serotype-specific detection of dengue virus. We also show the sensor' capability to selectively capture target nucleic acids from a heterogeneous mixture. The limit of detection is 1 pM for short 27 base target molecules in a 15-min assay. Similar hybridization results are shown for short DNA molecules as well as RNAs from Brucella and Escherichia coli. The versatility and simplicity of this low-cost biosensor should enable point-of-care diagnostics in food, medical and environmental safety markets.
- Published
- 2014
13. Electrochemical release of hepatocyte-on-hydrogel microstructures from ITO substrates
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Emile A. Schweikert, Li Jung Chen, Mihye Kim, Elena Foster, Giyoong Tae, Tam Vu, Stanislav V. Verkhoturov, Alexander Revzin, Sunny S. Shah, and Dipali Patel
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Materials science ,Surface Properties ,Ultraviolet Rays ,Electrochemistry ,Biochemistry ,Analytical Chemistry ,Polyethylene Glycols ,chemistry.chemical_compound ,Polymer chemistry ,Humans ,Electrodes ,Heparin ,Reverse Transcriptase Polymerase Chain Reaction ,technology, industry, and agriculture ,Tin Compounds ,Hydrogels ,Hep G2 Cells ,Silane ,Indium tin oxide ,Transplantation ,Photopolymer ,chemistry ,Self-healing hydrogels ,Hepatocytes ,Glass ,Ethylene glycol ,Micropatterning - Abstract
This paper describes a novel platform that utilizes micropatterning and electrochemistry to release cells-on-hydrogel microstructures from conductive indium tin oxide (ITO) substrates. In this approach, UV photopolymerization was employed to micropattern heparin-based hydrogels onto glass substrates containing ITO electrodes. ITO/glass substrates were first functionalized with acrylated silane to promote attachment of hydrogel structures. The surfaces containing hydrogel micropatterns were further functionalized with poly(ethylene glycol) thiol, rendering the regions around the hydrogel structures non-fouling to proteins and cells. After incubating surfaces with collagen (I), primary rat hepatocytes were shown to selectively attach on top of the hydrogel and not on surrounding glass/ITO regions. Electrical activation of specific ITO electrodes (−1.8 V vs. Ag/AgCl reference) was then used to release cells-on-hydrogel microstructures from the substrate. Immunostaining and reverse transcription polymerase chain reaction analysis of albumin, an important indicator of hepatic function, showed that the hepatocyte-on-hydrogel microstructures released from the surface maintained their function at levels similar to hepatocytes remaining on the culture substrate. In the future, switchable conductive substrates described here may be to collect cell samples at different time points and may also be used for harvesting cell-carrying vehicles for transplantation studies.
- Published
- 2011
14. Quantitative label-free characterization of avidin-biotin assemblies on silanized glass
- Author
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Li Jung Chen, S. V. Verkhoturov, Emile A. Schweikert, Sunny S. Shah, Jeong Hyun Seo, Alexander Revzin, and Michael J. Eller
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Silanes ,biology ,Analytical chemistry ,Substrate (chemistry) ,Biotin ,Spectrometry, Mass, Secondary Ion ,Biointerface ,Avidin ,Silane ,Article ,Analytical Chemistry ,Secondary ion mass spectrometry ,chemistry.chemical_compound ,Adsorption ,Immobilized Proteins ,chemistry ,Chemical engineering ,biology.protein ,Fullerenes ,Glass ,Bifunctional - Abstract
In this study, a time-of-flight secondary ion mass spectrometer TOF-SIMS, operating in the event-by-event bombardment/detection mode was used to characterize avidin-biotin assemblies on silane-modified glass substrates. SIMS was used to analyze several variants of the biointerface, including avidin physically adsorbed on a monofunctional acryl silane surface and covalently attached on monofunctional (amine terminated) and bifunctional (amine and acryl terminated) silanes. The goal of these studies was to determine density of avidin and biotin layers chemically or physically adsorbed on silanized glass substrate. An individual impact of a C(60) projectile used in this study creates a hemispherical crater (∼10 nm in diameter) and emits large numbers of secondary ions from the same nanovolume. Thus, a single impact enables one to unfold distinct secondary ions that span the thickness of the assembled film. This method was used to monitor the presence of glass, silane, and protein ions and to estimate the thickness and density of the avidin layer. In addition, we employed the double coincidence mass spectrometry approach to identify ions coemitted from a specific stratum of the biointerface. This approach was used to determine density of biotin and avidin immobilization while eliminating interferences from isobaric ions that originated from other constituents on the surface. Overall, novel TOF-SIMS quantitative approaches employed here were useful for examining complex biointerfaces and determining both lateral and in depth composition of the film.
- Published
- 2011
15. Use of photolithography to encode cell adhesive domains into protein microarrays
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Christopher C. Zimmer, Ji Youn Lee, Sunny S. Shah, Gang-yu Liu, and Alexander Revzin
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Photochemistry ,Protein domain ,Population ,Cell Culture Techniques ,Protein Array Analysis ,Nanotechnology ,Substrate (printing) ,Photoresist ,law.invention ,law ,Cell Line, Tumor ,Electrochemistry ,Fluorescence microscope ,Cell Adhesion ,Humans ,General Materials Science ,education ,Spectroscopy ,Cells, Cultured ,education.field_of_study ,Chemistry ,Surfaces and Interfaces ,Condensed Matter Physics ,Protein microarray ,Biophysics ,Photolithography ,Micropatterning - Abstract
Protein microarrays are rapidly emerging as valuable tools in creating combinatorial cell culture systems where inducers of cellular differentiation can be identified in a rapid and multiplexed fashion. In the present study, protein microarraying was combined with photoresist lithography to enable printing of extracellular matrix (ECM) protein arrays while precisely controlling "on-the-spot" cell-cell interactions. In this surface engineering approach, the micropatterned photoresist layer formed on a glass substrate served as a temporary stencil during the microarray printing, defining the micrometer-scale dimensions and the geometry of the cell-adhesion domains within the printed protein spots. After removal of the photoresist, the glass substrates contained micrometer-scale cell-adhesive regions that were encoded within 300 or 500 microm diameter protein domains. Fluorescence microscopy and atomic force microscopy (AFM) were employed to characterize protein micropatterns. When incubated with micropatterned surfaces, hepatic (HepG2) cells attached on 300 or 500 mum diameter protein spots; however, the extent of cell-cell contacts within each spot varied in accordance with dimensions of the photoresist stencil, from single cells attaching on 30 microm diameter features to multicell clusters residing on 100 or 200 microm diameter regions. Importantly, the photoresist removal process was shown to have no detrimental effects on the ability of several ECM proteins (collagens I, II, and IV and laminin) to support functional hepatic cultures. The micropatterning approach described here allows for a small cell population seeded onto a single cell culture substrate to be exposed to multiple scenarios of cell-cell and cell-surface interactions in parallel. This technology will be particularly useful for high-throughput screening of biological stimuli required for tissue specification of stem cells or for maintenance of differentiated phenotype in scarce primary cells.
- Published
- 2008
16. Patterning Cells on Optically Transparent Indium Tin Oxide Electrodes
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Alexander Revzin and Sunny S. Shah
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Materials science ,General Immunology and Microbiology ,General Chemical Engineering ,General Neuroscience ,Tin Compounds ,Cell Communication ,General Biochemistry, Genetics and Molecular Biology ,Polyethylene Glycols ,Indium tin oxide ,Cellular Biology ,chemistry.chemical_compound ,Microelectrode ,chemistry ,Chemical engineering ,Electrode ,Cell Adhesion ,Animals ,Humans ,Surface modification ,Glass ,Ferricyanide ,Cyclic voltammetry ,Microelectrodes ,Layer (electronics) ,Micropatterning - Abstract
The ability to exercise precise spatial and temporal control over cell-surface interactions is an important prerequisite to the assembly of multi-cellular constructs serving as in vitro mimics of native tissues. In this study, photolithography and wet etching techniques were used to fabricate individually addressable indium tin oxide (ITO) electrodes on glass substrates. The glass substrates containing ITO microelectrodes were modified with poly(ethylene glycol) (PEG) silane to make them protein and cell resistive. Presence of insulating PEG molecules on the electrode surface was verified by cyclic voltammetry employing potassium ferricyanide as a redox reporter molecule. Importantly, the application of reductive potential caused desorption of the PEG layer, resulting in regeneration of the conductive electrode surface and appearance of typical ferricyanide redox peaks. Application of reductive potential also corresponded to switching of ITO electrode properties from cell non-adhesive to cell-adhesive. Electrochemical stripping of PEG-silane layer from ITO microelectrodes allowed for cell adhesion to take place in a spatially defined fashion, with cellular patterns corresponding closely to electrode patterns. Micropatterning of several cell types was demonstrated on these substrates. In the future, the control of the biointerfacial properties afforded by this method will allow to engineer cellular microenvironments through the assembly of three or more cell types into a precise geometric configuration on an optically transparent substrate.
- Published
- 2007
17. On-cue detachment of hydrogels and cells from optically transparent electrodes
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Alexander Revzin, Sunny S. Shah, Ji Youn Lee, Giyoong Tae, and Mihye Kim
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Materials science ,Cell Culture Techniques ,Metals and Alloys ,Tin Compounds ,Biomaterial ,Hydrogels ,Nanotechnology ,3T3 Cells ,General Chemistry ,Fibroblasts ,Article ,Catalysis ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Indium tin oxide ,Mice ,Self-healing hydrogels ,Electrode ,Materials Chemistry ,Ceramics and Composites ,Animals ,Electrodes - Abstract
The goal of the present communication was to develop a strategy for detachment of cells and biomaterial constructs from indium tin oxide (ITO) electrodes.
- Published
- 2009
18. Integrating Sensing Hydrogel Microstructures into Micropatterned Hepatocellular Cocultures.
- Author
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Ji Youn Lee, Sunny S. Shah, Jun Yan, Michael C. Howland, Atul N. Parikh, Tingrui Pan, and Alexander Revzin
- Subjects
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BIOSENSORS , *HYDROGELS , *MICROSTRUCTURE , *LIVER cells , *PHOTORESISTS , *PHOTOLITHOGRAPHY , *COLLAGEN - Abstract
In this paper we describe a microfabrication-derived approach for defining interactions between distinct groups of cells and integrating biosensors with cellular micropatterns. In this approach, photoresist lithography was employed to micropattern cell-adhesive ligand (collagen I) on silane-modified glass substrates. Poly(ethylene glycol) (PEG) photolithography was then used to fabricate hydrogel microstructures in registration with existing collagen I domains. A glass substrate modified in this manner had three types of micrpatterned regions: cell-adhesive collagen I domains, moderately adhesive silanized glass regions, and nonadhesive PEG hydrogel regions. Incubation of this substrate with primary rat hepatocytes or HepG2 cells resulted in attachment of hepatic cells on collagen I domains with no adhesion observed on silane-modified glass regions or hydrogel domains. 3T3 fibroblasts added onto the same surface attached on the glass regions around the hepatocytes, completing the coculture. Significantly, PEG hydrogel microstructures remained free of cells and were used to “fence” hepatocytes from fibroblasts, thus limiting communication between the cell types. We also demonstrated that entrapment of enzyme molecules inside hydrogel microstructures did not compromise nonfouling properties of PEG. Building on this result, horse radish peroxidase-containing hydrogel microstructures were integrated into micropatterned cocultures and were used to detect hydrogen peroxide in the culture medium. The surface micropatterning approach described here may be used in the future to simultaneously define and detect endocrine signaling between two distinct cell types. [ABSTRACT FROM AUTHOR]
- Published
- 2009
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19. Use of Photolithography to Encode Cell Adhesive Domains into Protein Microarrays.
- Author
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Ji Youn Lee, Sunny S. Shah, Christopher C. Zimmer, Gang-yu Liu, and Alexander Revzin
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PHOTORESISTS , *MICROELECTRONICS , *MASKS (Electronics) , *PHOTOLITHOGRAPHY - Abstract
Protein microarrays are rapidly emerging as valuable tools in creating combinatorial cell culture systems where inducers of cellular differentiation can be identified in a rapid and multiplexed fashion. In the present study, protein microarraying was combined with photoresist lithography to enable printing of extracellular matrix (ECM) protein arrays while precisely controlling “on-the-spot” cell−cell interactions. In this surface engineering approach, the micropatterned photoresist layer formed on a glass substrate served as a temporary stencil during the microarray printing, defining the micrometer-scale dimensions and the geometry of the cell-adhesion domains within the printed protein spots. After removal of the photoresist, the glass substrates contained micrometer-scale cell-adhesive regions that were encoded within 300 or 500 m diameter protein domains. Fluorescence microscopy and atomic force microscopy (AFM) were employed to characterize protein micropatterns. When incubated with micropatterned surfaces, hepatic (HepG2) cells attached on 300 or 500 m diameter protein spots; however, the extent of cell−cell contacts within each spot varied in accordance with dimensions of the photoresist stencil, from single cells attaching on 30 m diameter features to multicell clusters residing on 100 or 200 m diameter regions. Importantly, the photoresist removal process was shown to have no detrimental effects on the ability of several ECM proteins (collagens I, II, and IV and laminin) to support functional hepatic cultures. The micropatterning approach described here allows for a small cell population seeded onto a single cell culture substrate to be exposed to multiple scenarios of cell−cell and cell−surface interactions in parallel. This technology will be particularly useful for high-throughput screening of biological stimuli required for tissue specification of stem cells or for maintenance of differentiated phenotype in scarce primary cells. [ABSTRACT FROM AUTHOR]
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- 2008
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20. Assessing Academic Preferential Hiring Practices in Highly Ranked Otolaryngology Departments.
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Warner BK, Munhall CC, Shah S, Pitiranggon C, Camilon TJM, Nguyen SA, and Labadie RF
- Abstract
Objective: To assess whether preferential hiring practices, particularly self-hiring, are present in academic otolaryngology departments. Setting: A list of academic Otolaryngology-Head and Neck Surgery (O-HNS) departments ranked #1-40 was generated from the Doximity 2021 rankings. The educational background and training information of clinical faculty members and departmental leadership was extracted from each department's online directories. Methods: Descriptive statistics were used to examine inter/intradepartmental relationships and affiliations of included clinical faculty and departmental leadership based on current employment and medical training sites. A "prior affiliation ratio" was calculated to assess the degree of self-hiring and account for multiple possible prior affiliations (medical school, residency, and fellowship) by dividing all prior self-hired affiliations of faculty by the total number of faculty at each department. Results: A total of 1344 clinical faculty were identified, and 596 (44.35%) had at least 1 prior affiliation with their department. The overall prior affiliation ratio was 0.6, and 7 departments had a value >0.8, with the highest being 1.27 (>1.0 indicating multiple prior affiliations per individual such as both residency and fellowship). A network map of departments #1-10 showed heavy intradepartmental faculty recruitment with 24% of faculty having completed a #1-10 residency, 24% a #11-20 residency, 13% a #21-30 residency, and 11% a #31-40 residency. Totaling this data, 76% of faculty at departments ranked #1-10 had completed training at a program ranked #1-40. Furthermore, our data shows high rates of self-hiring among departmental leadership, (40% of Departmental Chairs and 62.5% of Program Directors) though rates are not significantly higher than self-hiring among faculty overall. Conclusion: The top 40 ranked O-HNS departments have high rates of self-hiring, relying on prestige of training programs and prior affiliation in hiring decisions. The effect on departmental productivity and training is unclear., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: Dr Robert F. Labadie is a consultant for Spiral Therapeutics and receives NIH funding for other projects.
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- 2024
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21. Efficacy of a Serotonin-Norepinephrine Reuptake Inhibitor as a Treatment for Meniere Disease: A Randomized Clinical Trial.
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Rizk H, Monaghan NP, Shah S, Liu Y, Keith BA, Jeong S, and Nguyen SA
- Abstract
Importance: Meniere disease accounts for up to 15% of new vestibular diagnoses,; however, the optimal treatment has yet to be identified. A conservative treatment that would reduce or stop the vertigo episodes has not been identified., Objective: To determine the efficacy of a serotonin-norepinephrine reuptake inhibitor, venlafaxine, compared to placebo in treating patients with Meniere disease., Design, Setting, and Participants: This was a randomized, double-blind, placebo-controlled, crossover pilot study spanning 22 weeks of follow-up. The clinical trial took place at a single-center tertiary referral center in Charleston, South Carolina. Participants were eligible if they were 18 years or older, had definite Meniere disease criteria as defined by Barany criteria, had at least 2 episodes in the last month, had not received intratympanic gentamycin, skull base surgery, or radiation therapy to the head or neck, not currently taking diuretics for Meniere disease, not currently taking oral steroids, and not currently taking serotonin-modulating medication. Patients were enrolled between February 2020 and September 2023., Interventions: Patients received either 1 venlafaxine tablet, 37.5 mg, taken daily by mouth for 8 weeks or 1 placebo tablet taken daily by mouth for 8 weeks. Group 1 received placebo during phase 1 of the trial and venlafaxine in phase 2 of the trial. Group 2 received venlafaxine during phase 1 of the trial and placebo in phase 2 of the trial., Main Outcomes and Measures: The main outcomes included the number of episodes and scores on the following scales: Dizziness Handicap Inventory, Neuropsychological Vertigo Inventory, Meniere Disease Patient-Oriented Symptom Index, 20-Item Short Form Health Survey, Penn State Worry Questionnaire, Cognitive Failure Questionnaire., Results: A total of 182 patients were screened, and 40 participants with Meniere disease enrolled in the trial. The mean (SD) age of participants was 56.6 (14.3) years, and 22 (55%) were female. Participants had a mean (SD) of 13.8 (10.1) episodes per phase at baseline, 5.4 (4.4) episodes (Δ8.4) during the venlafaxine phase, and 5.0 (4.6) episodes (Δ8.8) during the placebo phase. No significant difference was identified between venlafaxine and placebo groups in the number of episodes or quality-of-life metrics., Conclusions and Relevance: This randomized clinical trial failed to identify a difference between venlafaxine and placebo in number of episodes and other quality-of-life metrics. Future studies may benefit from different dosing regimens, larger cohorts, and longer lengths of therapy., Trial Registration: ClinicalTrials.gov Identifier: NCT04218123.
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- 2024
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22. Stability Indicating RP-HPLC-DAD method for simultaneous estimation of tadalafil and macitentan in synthetic mixture for treatment of pulmonary arterial hypertension.
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Gol D, Vyas A, Visana N, Patel A, Shah S, Sheth D, and Dholakia S
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- Humans, Chromatography, High Pressure Liquid methods, Tadalafil, Reproducibility of Results, Drug Stability, Pulmonary Arterial Hypertension, Pyrimidines, Sulfonamides
- Abstract
Objective: High Performance liquid chromatography is an integral analytical tool in assessing drug product stability. A simple, selective, precise, accurate and stability indicating RP-HPLC method was developed and validated for analysis of Tadalafil and Macitentan in synthetic mixture., Material and Method: Chromatographic separation was performed using Phenomex Gemini C18 (25cm×4.6nm, 5μm) Column. The mobile phase consists of (10mM Ammonium Acetate in water and [Methanol: ACN 20: 80% v/v]) (40: 60% v/v). The flow rate was set to be 1.0mL/min. The injection volume was 10.00μL. The detection was carried out at 260nm at column temperature 35°C., Results: The method was validating according to ICH Q
2 R1 guideline for accuracy, precision, reproducibility, specificity, robustness and detection and quantification limits. Stability testing was performed on Tadalafil and Macitentan and it was found that these degraded sufficiently in all applied chemical and physical conditions. Linearity for Tadalafil and Macitentan was observed 0.4-100μg/mL and 0.1-25μg/mL with correlation coefficient at 0.9999. LOD and LOQ 0.008μg/mL and 0.024μg/mL and 0.001μg/mL and 0.0029μg/mL for Tadalafil and Macitentan respectively., Conclusion: The developed RP-HPLC method was found to be suitable for the determination of both the drugs., (Copyright © 2023 Académie Nationale de Pharmacie. Published by Elsevier Masson SAS. All rights reserved.)- Published
- 2024
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23. Lipids Fortified Nano Phytopharmaceuticals: A Breakthrough Approach in Delivering Bio-actives for Improved Therapeutic Efficacy.
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Shah S, Chauhan H, Madhu H, Mori D, Soniwala M, Singh S, and Prajapati B
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Phytopharmaceuticals, derived from natural sources, manifest tremendous potential for therapeutic applications. Nevertheless, effective delivery of these bio-actives presents significant challenges. A breakthrough in fortifying phytopharmaceuticals within phosphatidylcholine is a promising remedy to overcome solubility, permeability, and other related drawbacks. This intrinsic lipid, which is obtained from both natural and synthetic sources, confers numerous benefits, encompassing heightened solubility, augmented bioavailability, and enhanced stability. The conjugation of phytopharmaceuticals with phosphatidylcholine enables improved dermal permeation, absorption, targeted distribution, and the possibility of synergistic results, eventually improving therapeutic efficacy. Additionally, the use of phytopharmaceuticals enriched with phosphatidylcholine presents a promising route for overcoming the limitations imposed by conventional delivery techniques, encouraging more effective treatments. The review provides a thorough analysis of phosphatidylcholine- incorporated phytopharmaceuticals as nanomedicine with variables that significantly affect their therapeutic efficacy. Moreover, the review elaborates on how phosphatidylcholine improves solubility, permeability, and tissue distribution and boosts the potential of phytopharmaceuticals. Further, the review underscores the significance of nano-formulation strategies, analytical methodologies, and forthcoming prospects to propel this field forward. Furthermore, the review emphasizes the potential inherent in this innovative approach while highlighting the importance of additional research endeavors and collaborative initiatives to unlock the therapeutic benefits of phosphatidylcholinefortified phytopharmaceuticals, enhancing patient well-being., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)
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- 2024
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24. Item Level Psychometrics of the Dizziness Handicap Inventory in Vestibular Migraine and Meniere's Disease.
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Rizk HG, Velozo C, Shah S, Hum M, Sharon JD, and Mcrackan TR
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- Humans, Female, Adult, Middle Aged, Aged, Male, Dizziness diagnosis, Psychometrics, Surveys and Questionnaires, Vertigo, Meniere Disease diagnosis, Migraine Disorders diagnosis
- Abstract
Objectives: Evaluate the measurement properties of the Dizziness Handicap Inventory (DHI) using item response theory in patients diagnosed with vestibular migraine (VM) and Meniere's disease (MD)., Design: One hundred twenty-five patients diagnosed with VM and 169 patients diagnosed with MD by a vestibular neurotologist according to the Bárány Society criteria in two tertiary multidisciplinary vestibular clinics and who completed the DHI at their initial visit, were included in the study. The DHI (total score and individual items) was analyzed using the Rasch Rating Scale model for patients in each subgroup, VM and MD, and as a whole group. The following categories were assessed: rating-scale structure, unidimensionality, item and person fit, item difficulty hierarchy, person-item match, and separation index, standard error of measurement, and minimal detectable change (MDC)., Results: Patients were predominantly female (80% of the VM subgroup and 68% of the MD subgroup) with a mean age of 49.9 ± 16.5 years and 54.1 ± 14.2 years, respectively. The mean total DHI score for the VM group was 51.9 ± 22.3 and for the MD group was 48.5 ± 26.6 ( p > 0.05). While neither all items nor the separate constructs met all criteria for unidimensionality (i.e., items measuring a single construct), post hoc analysis showed that the all-item analysis supported a single construct. All analyses met the criterion for showing a sound rating scale and acceptable Cronbach's alpha (≥0.69). The all-item analysis showed the most precision, separating the samples into three to four significant strata. The separate-construct analyses (physical, emotional, and functional) showed the least precision, separated the samples into less than three significant strata. Regarding MDC, the MDC remained consistent across the analyses of the different samples; approximately 18 points for the full analyses and approximately 10 points for the separate construct (physical, emotional, and functional)., Conclusions: Our evaluation of the DHI using item response theory shows that the instrument is psychometrically sound and reliable. The all-item instrument fulfills criteria for essential unidimensionality but does seem to measure multiple latent constructs in patients with VM and MD, which has been reported in other balance and mobility instruments. The current subscales did not show acceptable psychometrics, which is in line with multiple recent studies favoring the use of the total score. The study also shows that the DHI is adaptable to episodic recurrent vestibulopathies. The total score shows better precision and separation of subjects in up to four strata compared to the separate construct that separate subjects into less than three strata. The measurement error smallest detectable change was found in our analysis to be 18 points, which means any change in the DHI of less than 18 points is not likely to be clinically significant. The minimal clinically important difference remains indeterminate., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)
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- 2024
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25. Otolaryngologic Presentations to Emergency Departments During the COVID-19 Pandemic: A Systematic Review and Meta-Analysis.
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Munhall CC, Shah S, Nguyen SA, Meyer TA, Schlosser RJ, and White DR
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- Aged, Child, Humans, SARS-CoV-2, Pandemics prevention & control, Epistaxis, Communicable Disease Control, Emergency Service, Hospital, Retrospective Studies, COVID-19 epidemiology, Foreign Bodies
- Abstract
Objectives: To perform a systematic review of otolaryngologic presentation rates to emergency department settings before and after lockdown due to the COVID-19 pandemic., Sources: PubMed, Scopus, and CINAHL., Methods: A systematic search was conducted following PRISMA guidelines (Preferred Reporting Items for Systematic Reviews and Meta-analyses) for studies describing otolaryngologic presentations to emergency department and rapid access clinic settings both in the before-lockdown and after-lockdown periods. The start of after-lockdown period varied based on initiation of lockdown, ranging from March 1st to June 1st of 2020 across general emergency department studies., Results: A total of 14 studies were included in this review. About 10 were general emergency departments, 3 were specifically pediatric emergency departments, and 1 study focused on the geriatric population (>65 years). A total of 13 790 patients were included, with 9446 in the before-lockdown period (68.5%) and 4344 in the after-lockdown period (31.5%). Meta-analysis of proportions for otolaryngologic presentations across general emergency departments was performed. Comparison of weighted proportions found significant differences between before-lockdown and after-lockdown presentation rates for infectious etiologies, tonsillitis specifically, foreign bodies, non-infectious airway issues, and epistaxis among these studies., Conclusions: The increased proportions of various non-infectious presentations (eg, epistaxis, foreign bodies, and airway issues) following lockdown might be associated with proportional decreases in infectious pathologies, given decreased social contact to prevent SARS-CoV-2 transmission. Overall, it is important for otolaryngologists to recognize what presentations might more commonly be seen and require evaluation and potential intervention in light of a global pandemic.
- Published
- 2023
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26. Secondary autoimmune immune ear disease (AIED): a systematic review and meta-analysis on vestibular manifestations of systemic autoimmune and inflammatory disorders.
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Shah S, Chidarala S, Jeong S, Zhang K, Nguyen SA, Wilkinson R, Ward C, and Rizk H
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- Humans, Ear Diseases, Autoimmune Diseases
- Abstract
Secondary autoimmune inner ear disease (AIED) is often bilateral and asymmetric in patients presenting with audiovestibular symptoms due to a systemic autoimmune disease. This systematic review and meta-analysis are aimed at identifying and highlighting patterns in prevalence of vestibular dysfunction, symptom presentation, and diagnostic methods in extant literature by combining clinical context from case reports with quantitative analyses from cohort studies. Screening of articles by title, abstract, and full text was completed by four reviewers (K.Z., A.L., S.C., and S.J.). In this study, we grouped secondary AIED and systemic autoimmune diseases by pathophysiologic mechanism: (1) connective tissue disease (CTD), (2) vasculitides (VAS), (3) systemic inflammatory disorders (SID), and (4) other immune-mediated disorders (OIMD). The search for AIED disease identified 120 articles (cohorts and case reports) that met the final inclusion criteria. All 120 were included in the qualitative review, and 54 articles were included for meta-analysis. Of these 54 articles, 22 included a control group (CwC). Ninety individual cases or patient presentations from 66 articles were included for analysis in addition to the 54 cohort articles. Secondary AIED does not have a diagnostic algorithm for managing vestibular symptoms. The management of audiovestibular symptoms requires close collaboration between otolaryngologists and rheumatologists to preserve end-organ function of the ear. To improve our ability to understand the impact on the vestibular system, vestibular clinicians need to develop a standardized reporting method. Clinical presentation should frequently be paired with vestibular testing to contextually investigate symptom severity and provide higher quality care., (© 2023. International League of Associations for Rheumatology (ILAR).)
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- 2023
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27. Safely Shaping the Breast After Implant Removal and Total Intact Capsulectomy Using the Mammary Imbrication Lift and Fixation Technique.
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Lampert JA, Townsend AN, Shah S, Bouz A, and Nichols N
- Abstract
Background: Implant-based breast augmentation is one of the most popular plastic surgery procedures performed worldwide. As the number of patients who have breast implants continues to rise, so does the number of those who request breast implant removal without replacement. There is little in the current scientific literature describing total intact capsulectomy and simultaneous mastopexy procedures., Objectives: Here, the authors present their current method using the mammary imbrication lift and fixation technique after explant and total capsulectomy., Methods: Between 2016 and 2021, a total of 64 patients (mean age: 42.95 years; range, 27-78 years) underwent the described mammary imbrication lift and fixation technique with bilateral breast implant removal and total capsulectomy., Results: Mean follow-up was 6.5 months (range, 1-36 months). Postoperative complications included minor cellulitis in 1 patient (1.6%), late onset hematoma with infection in 1 patient (1.6%), fat necrosis and pulmonary embolism in 1 patient with prior history of thromboembolic events (1.6%), and breast scar irregularity in 4 patients (6.2%) who required subsequent minor scar revision or steroid injections. Two patients (1.6%) underwent revision surgery with bilateral breast fat grafting to improve shape and add volume., Conclusions: The mammary imbrication lift and fixation technique described here can safely and simultaneously be performed with a total intact capsulectomy and explant procedure. This technique avoids wide undermining, intentionally opening the capsule, performing subtotal capsulectomy, and preserving blood supply to the breast tissue and nipple with low complication rates., (© The Author(s) 2023. Published by Oxford University Press on behalf of The Aesthetic Society.)
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- 2023
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28. Systematic review of cochlear implantation in patients with inner ear malformations.
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Shah S, Walters R, Langlie J, Davies C, Finberg A, Tuset MP, Ebode D, Mittal R, and Eshraghi AA
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- Humans, Retrospective Studies, Treatment Outcome, Cochlear Implantation methods, Cochlear Implants, Ear, Inner surgery, Hearing Loss, Sensorineural surgery, Hearing Loss, Sensorineural etiology
- Abstract
Objectives: To evaluate the outcomes of cochlear implantation in patients with severe to profound sensorineural hearing loss due to inner ear malformations (IEMs) when compared to patients without IEMs. We discussed audiological outcomes such as open-set testing, closed-set testing, CAP score, and SIR score as well as postoperative outcomes such as cerebrospinal fluid gusher and incomplete insertion rate associated with cochlear implantation in individuals with IEMs., Data Sources: PubMed, Science Direct, Web of Science, Scopus, and EMBASE databases., Review Methods: After screening a total of 222 studies, twelve eligible original articles were included in the review to analyze the speech and hearing outcomes of implanted patients with IEMs. Five reviewers independently screened, selected, and extracted data. The "Tool to Assess Risk of Bias in Cohort Studies" published by the CLARITY group was used to perform quality assessment on eligible studies. Systematic review registration number: CRD42021237489., Results: IEMs are more likely to be associated with abnormal position of the facial nerve, raising the risk of intraoperative complications. These patients may benefit from cochlear implantation, but audiological outcomes may also be less favorable than in individuals without IEMs. Furthermore, due to the risk of cerebrospinal fluid gusher, incomplete insertion of electrodes, and postoperative facial nerve stimulation, surgeons can employ precautionary measures such as preoperative imaging and proper counseling. Postoperative imaging is suggested to be beneficial in ensuring proper electrode placement., Conclusions: Cochlear implants (CIs) have the potential to provide auditory rehabilitation to individuals with IEMs. Precise classification of the malformation, preoperative imaging and anatomical mapping, appropriate electrode selection, intra-operative techniques, and postoperative imaging are recommended in this population., Competing Interests: The authors have declared that no competing interests exist.
- Published
- 2022
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29. Amelioration of intracerebroventricular streptozotocin-induced cognitive dysfunction by Ocimum sanctum L. through the modulation of inflammation and GLP-1 levels.
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Patel B, Sheth D, Vyas A, Shah S, Parmar S, Patel C, Patel S, Beladiya J, Pande S, and Modi K
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- Animals, Male, Rats, Congo Red, Disease Models, Animal, Inflammation chemically induced, Maze Learning, Memory Disorders chemically induced, Memory Disorders drug therapy, Ocimum sanctum chemistry, Rats, Wistar, Streptozocin toxicity, Tumor Necrosis Factor-alpha, Alzheimer Disease drug therapy, Cognitive Dysfunction chemically induced, Cognitive Dysfunction drug therapy, Dipeptidyl-Peptidase IV Inhibitors pharmacology, Glucagon-Like Peptide 1 analysis, Plant Extracts pharmacology
- Abstract
DPP-4 inhibitors have been shown to reverse amyloid deposition in Alzheimer's disease (AD) patients with cognitive impairment. Ocimum sanctum L. leaves reported the presence of important phytoconstituents which are reported to have DPP-4 inhibitory activity. To investigate the effects of petroleum ether extract of Ocimum sanctum L. (PEOS) in Intracerebroventricular streptozotocin (ICV-STZ) induced AD rats. ICV-STZ (3 mg/kg) was injected bilaterally into male Wistar rats, while sham animals received the artificial CSF. The ICV-STZ-induced rats were administered with three doses of PEOS (100, 200, and 400 mg/kg, p.o.) for thirty days. All experimental rats were subjected to behaviour parameters (radial arm maze task and novel object recognition test), neurochemical parameters such as GLP-1, Aβ42, and TNF-α levels, and histopathological examination (Congo red staining) of the left brain hemisphere. PEOS significantly reversed the spatial learning and memory deficit exhibited by ICV-STZ-induced rats. Furthermore, PEOS also shows promising results in retreating Aβ deposition, TNF α, and increasing GLP-1 levels. The histopathological study also showed a significant dose-dependent reduction in amyloid plaque formation and dense granule in PEOS -treated rats as compared to the ICV-STZ induced rats (Negative control). The results show that extract of Ocimum sanctum L. attenuated ICV-STZ-induced learning and memory deficits in rats and has the potential to be employed in the therapy of AD., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)
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- 2022
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30. Lipid-based emulsion drug delivery systems - a comprehensive review.
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Dhaval M, Vaghela P, Patel K, Sojitra K, Patel M, Patel S, Dudhat K, Shah S, Manek R, and Parmar R
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- Administration, Oral, Biological Availability, Emulsions chemistry, Lipids chemistry, Particle Size, Solubility, Surface-Active Agents chemistry, Drug Delivery Systems, Excipients chemistry
- Abstract
Lipid-based emulsion system - a subcategory of emulsion technology, has emerged as an enticing option to improve the solubility of the steadily rising water-insoluble candidates. Along with enhancing solubility, additional advantages such as improvement in permeability, protection against pre-systemic metabolism, ease of manufacturing, and easy to scale-up have made lipid-based emulsion technology very popular among academicians and manufacturers. The present article provides a comprehensive review regarding various critical properties of lipid-based emulsion systems, such as microemulsion, nanoemulsion, SMEDDS (self microemulsifying drug delivery system), and SNEDDS (self nanoemulsifying drug delivery system). The present article also explains in detail the similarities and differences between them, the stabilization mechanism, methods of preparation, excipients used to prepare them, and evaluation techniques. Subtle differences between nearly related terminologies such as microemulsion and nanoemulsion, SMEDDS, and SNEDDS are also explained in detail to clarify the basic differences. The present article also gives in-depth information regarding the chemical structure of various lipidic excipients, various possible chemical modifications to modify their inherent properties, and their regulatory status for rational selection., (© 2021. Controlled Release Society.)
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- 2022
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31. Effect of Postoperative Radiation Therapy Timing on Survival in Pediatric and Young Adult Ependymoma.
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Shah S, Gates K, Mallory C, Rubens M, Maher OM, Niazi TN, Khatib Z, Kotecha R, Mehta MP, and Hall MD
- Abstract
Purpose: Postoperative radiation therapy (RT) is commonly used for World Health Organization grade II-III intracranial ependymoma. Clinicians generally aim to begin RT ≤5 weeks after surgery, but postoperative recovery and need for second look surgery can delay the initiation of adjuvant therapy. On ACNS 0831, patients were required to enroll ≤8 weeks after initial surgery and begin adjuvant therapy within 3 weeks after enrollment. The purpose of this study was to determine the optimal timing of RT after surgery., Methods and Materials: The National Cancer Database was queried for patients (aged 1-39 years) with localized World Health Organization grade II-III intracranial ependymoma treated with surgery and postoperative RT. Overall survival (OS) curves were plotted based on RT timing (≤5 weeks, 5-8 weeks, and >8 weeks after surgery) and were compared by log-rank test. Factors associated with OS were identified by multivariate analysis. After 2009, complete data were available on whether patients underwent gross total resection or subtotal resection. Planned subset analysis was performed to examine the effect of RT timing on OS in patients with known extent of resection., Results: In the final analytical data set of 1043 patients, no difference in 3-year OS was observed in patients who initiated RT ≤5 weeks, 5 to 8 weeks, and >8 weeks after surgery (89.8% vs 89.1% vs 88.4%; P = .796). On multivariate analysis, grade III tumors (hazard ratio, 2.752; 95% confidence interval, 1.969-3.846, P < .001) and subtotal resection (hazard ratio, 2.253; 95% confidence interval, 1.405-3.611, P < .001) were significantly associated with reduced OS. Timing of RT, total RT dose, age, and other factors were not significant. These findings were affirmed in the subset of patients treated between 2010 and 2016, when extent of resection was routinely recorded., Conclusions: Delayed postoperative RT was not associated with inferior survival in patients with intracranial ependymoma. Delayed RT initiation may be acceptable in patients who require longer postoperative recovery or referral to an appropriate RT center, but should be minimized whenever practical., (© 2021 The Author(s).)
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- 2021
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32. Development and Optimization of Inhalable Levofloxacin Nanoparticles for The Treatment of Tuberculosis.
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Shah S, Ghetiya R, Soniwala M, and Chavda J
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- Drug Liberation, Humans, Particle Size, Chitosan, Drug Carriers, Levofloxacin administration & dosage, Nanoparticles, Tuberculosis drug therapy
- Abstract
Background: Levofloxacin has been recommended by the WHO for the treatment of pulmonary tuberculosis and inhalable delivery of levofloxacin can be advantageous over conventional delivery., Objective: This study aimed to develop and optimize inhalable levofloxacin Loaded Chitosan Nanoparticles (LCN). The objective was to achieve the mean particle size of LCN less than 300nm, sustain the drug release up to 24 h, and achieve MMAD of LCN of less than 5μm., Methods: LCN were prepared by ionic gelation of chitosan with sodium tripolyphosphate (STPP) and subsequent lyophilization. A Plackett Burman screening design, 32 full factorial design, and overlay plots were sequentially employed to optimize the formulation. The mean particle size, % entrapment efficiency, in vitro drug release, and minimum inhibitory concentration were all evaluated., Results: The Pareto chart from the Placket Burman screening design revealed that the concentrations of chitosan and STPP was found to be significant (p < 0.05). Further analysis by 32 full factorial design revealed that F-ratio for each model generated was found to be greater than the theoretical value (p < 0.05), confirming the significance of each model., Conclusion: The optimized formulation showed a mean particle size of 171.5 nm, sustained the drug release up to 24 h in simulated lung fluid, and revealed MMAD of 3.18 μm, which can confirm delivery of the drug to the deep lung region. However, further in vivo studies are required to design a suitable dosage regimen and establish the fate of nanoparticles for safe and efficacious delivery of the drug., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)
- Published
- 2021
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33. An approach to evaluate myocardial perfusion defect assessment for projection-based DECT: A phantom study.
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Han D, Shah S, Lee JH, Elmore K, Gransar H, Danad I, Kumar V, Raman S, Hartaigh BÓ, Dunham S, Lin FY, and Min JK
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- Algorithms, Humans, Iodine, Myocardium, Phantoms, Imaging, Radiography, Dual-Energy Scanned Projection methods, Sensitivity and Specificity, Tomography, X-Ray Computed methods, Myocardial Perfusion Imaging
- Abstract
Introduction: Dual-energy CT (DECT) can improve the accuracy of myocardial perfusion CT with projection-based monochromatic (DECT-MCE) and quantification of myocardial iodine in material decomposition (DECT-MD) reconstructions. However, evaluation of multiple reconstructions is laborious and the optimal reconstruction to detect myocardial perfusion defects is unknown., Methods: Left ventricular (LV) phantoms with artificial perfusion defects were scanned using DECT and single energy cardiac computed tomography angiography (SECT). Reconstructions of DECT-MCE at 40, 70, 100 and 140 keV, DECT-MD pairs of water, iodine, iron and fat, and SECT were evaluated using a 17-segment myocardial model. The diagnostic performance of each reconstruction was calculated on a per-segment basis and compared across DECT reconstructions., Results: Over 34 phantoms with artificial perfusion defects were found in 64/578 (11%) of segments, the sensitivity of DECT-MCE at 40, 70, 100, and 140 keV was 100% (95% confidence interval (CI): 93-100), 100% (95% CI: 93-100), 71% (95% CI: 56-83), and 25% (95% CI: 14-40), respectively, with a significant decline between 70 keV and 100 keV (p < 0.001). The specificity of DECT-MCE was 100% at all energies (95% CI: 99-100). As a group, the DECT-MD iodine background reconstructions had significantly lower sensitivity than the remaining modes (2.1% [95% CI, 0.05-11.1], vs. 100% [95% CI, 92.6-100], p < 0.001). Specificity of all material pair modes remained 100%., Conclusions: Using LV phantom models, the approach with the best sensitivity and specificity to assess myocardial perfusion defects with DECT are reconstructions of DECT-MCE at 40 or 70 KeV and DECT-MD without iodine background., Competing Interests: Conflict of interest Dr. James K. Min receives funding from GE Healthcare and serves on the scientific advisory board of Arineta and GE Healthcare. Dr. Min also has an equity interest in and is an employee of Cleerly, Inc. The remaining authors have no relevant disclosures, (Copyright © 2019. Published by Elsevier Inc.)
- Published
- 2020
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34. Psychosocial emergencies in the elderly.
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Ouellette L, Halasa R, Brown A, Ong C, Beckett R, Shah S, Patel D, McNinch D, and Jones J
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- Aftercare, Aged, Aged, 80 and over, Humans, Retrospective Studies, Social Problems, Transitional Care, Emergency Service, Hospital, Mental Disorders therapy, Referral and Consultation, Social Welfare
- Published
- 2019
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35. Design, Optimization, and Evaluation of Lurasidone Hydrochloride Nanocrystals.
- Author
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Shah S, Parmar B, Soniwala M, and Chavda J
- Subjects
- Calorimetry, Differential Scanning methods, Chemistry, Pharmaceutical methods, Freeze Drying, Particle Size, Powders chemistry, Solubility, X-Ray Diffraction methods, Lurasidone Hydrochloride chemistry, Nanoparticles chemistry
- Abstract
The present investigation was carried out to design, optimize, and evaluate lurasidone hydrochloride nanocrystals for improving its solubility and dissolution characteristics. Nanocrystals were prepared by media milling technique using zirconium oxide beads with 0.1 mm diameter. Various stabilizers, viz. poloxamer 188, PVP K30, SLS, HPMC E15, and PVP S 630 D, were evaluated to stabilize the nanocrystals. The Pareto chart obtained through Plackett-Burman screening design revealed that HPMC E 15 showed the highest standardized effect (p value <0.05) on percent dissolution efficiency at 2 min. In subsequent studies, a 3(2) factorial design was employed to quantify the effect of two independent variables, namely amount of stabilizer and milling time on predetermined response variables mean particle size, saturation solubility, and percent dissolution efficiency at 2 min. Statistical analysis of the factorial design revealed that all predetermined response variables were significantly dependent (p value <0.05) on the independent variables. The observed response of the optimized batch prepared as per the desirability function was in close agreement with predicted response, and mathematical model generated was validated. The optimized batch was lyophilized, and X-ray powder diffraction studies indicated that there was no substantial change in crystallinity of the drug. The optimized formulation showed mean particle size of 228 nm and released almost all the drug within first 5 min. Since the crystallinity of the drug is maintained, improvement in saturation solubility and dissolution efficiency could be attributed to decrease in mean particle size of the drug.
- Published
- 2016
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- View/download PDF
36. Intravenous heparin dosing strategy in hospitalized patients with atrial dysrhythmias.
- Author
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Roswell RO, Greet B, Shah S, Bernard S, Milin A, Lobach I, Guo Y, Radford MJ, and Berger JS
- Subjects
- Acute Coronary Syndrome, Anticoagulants therapeutic use, Arrhythmias, Cardiac complications, Blood Coagulation drug effects, Dose-Response Relationship, Drug, Hemorrhage chemically induced, Heparin adverse effects, Hospitalization, Humans, Infusions, Intravenous, Partial Thromboplastin Time, Stroke prevention & control, Thromboembolism, Arrhythmias, Cardiac drug therapy, Heart Atria physiopathology, Heparin administration & dosage
- Abstract
Patients with non-valvular atrial fibrillation (AF) have an elevated stroke risk that is 2-7 times greater than in those without AF. Intravenous unfractionated heparin (UFH) is commonly used for hospitalized patients with atrial fibrillation and atrial flutter (AFL) to prevent stroke. Dosing strategies exist for intravenous anticoagulation in patients with acute coronary syndromes and venous thromboembolic diseases, but there are no data to guide providers on a dosing strategy for intravenous anticoagulation in patients with AF/AFL. 996 hospitalized patients with AF/AFL on UFH were evaluated. Bolus dosing and initial infusion rates of UFH were recorded along with rates of stroke, thromboemobolic events, and bleeding events as defined by the International Society on Thrombosis and Haemostasis criteria. Among 226 patients included in the analysis, 76 bleeding events occurred. Using linear regression analysis, initial rates of heparin infusion ranging from 9.7 to 11.8 units/kilogram/hour (U/kg/h) resulted in activated partial thromboplastin times that were within therapeutic range. The median initial infusion rate in patients with bleeding was 13.3 U/kg/h, while in those without bleeding it was 11.4 U/kg/h; p = 0.012. An initial infusion rate >11.0 U/kg/h yielded an OR 1.95 (1.06-3.59); p = 0.03 for any bleeding event. Using IV heparin boluses neither increased the probability of attaining a therapeutic aPTT (56.1 vs 56.3 %; p = 0.99) nor did it significantly increase bleeding events in the study (35.7 vs 31.3 %; p = 0.48). The results suggest that higher initial rates of heparin are associated with increased bleeding risk. From this dataset, initial heparin infusion rates of 9.7-11.0 U/kg/h without a bolus can result in therapeutic levels of anticoagulation in hospitalized patients with AF/AFL without increasing the risk of bleeding.
- Published
- 2016
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37. Metronomic Doses of Temozolomide Enhance the Efficacy of Carbon Nanotube CpG Immunotherapy in an Invasive Glioma Model.
- Author
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Ouyang M, White EE, Ren H, Guo Q, Zhang I, Gao H, Yanyan S, Chen X, Weng Y, Da Fonseca A, Shah S, Manuel ER, Zhang L, Vonderfecht SL, Alizadeh D, Berlin JM, and Badie B
- Subjects
- Animals, Antineoplastic Agents pharmacology, Antineoplastic Agents therapeutic use, Brain Neoplasms pathology, Cell Death drug effects, Cell Line, Tumor, Dacarbazine therapeutic use, Disease Models, Animal, Dose-Response Relationship, Drug, Female, Glioma pathology, Inflammation pathology, Lipids chemistry, Mice, Inbred C57BL, Neoplasm Invasiveness, Polyethylene Glycols chemistry, Spleen pathology, Temozolomide, Treatment Outcome, Brain Neoplasms drug therapy, Dacarbazine analogs & derivatives, Glioma drug therapy, Immunotherapy, Nanotubes, Carbon chemistry, Oligodeoxyribonucleotides therapeutic use
- Abstract
Even when treated with aggressive current therapies, most patients with glioblastoma survive less than two years. Rapid tumor growth, an invasive nature, and the blood-brain barrier, which limits the penetration of large molecules into the brain, all contribute to the poor tumor response associated with conventional therapies. Immunotherapy has emerged as a therapeutic approach that may overcome these challenges. We recently reported that single-walled carbon nanotubes (SWCNTs) can be used to dramatically increase the immunotherapeutic efficacy of CpG oligonucleotides in a mouse model of glioma. Following implantation in the mouse brain, the tumor cell line used in these previous studies (GL261) tends to form a spherical tumor with limited invasion into healthy brain. In order to evaluate SWCNT/CpG therapy under more clinically-relevant conditions, here we report the treatment of a more invasive mouse glioma model (K-Luc) that better recapitulates human disease. In addition, a CpG sequence previously tested in humans was used to formulate the SWCNT/CpG which was combined with temozolomide, the standard of care chemotherapy for glioblastoma patients. We found that, following two intracranial administrations, SWCNT/CpG is well-tolerated and improves the survival of mice bearing invasive gliomas. Interestingly, the efficacy of SWCNT/CpG was enhanced when combined with temozolomide. This enhanced anti-tumor efficacy was correlated to an increase of tumor-specific cytotoxic activity in splenocytes. These results reinforce the emerging understanding that immunotherapy can be enhanced by combining it with chemotherapy and support the continued development of SWCNT/CpG.
- Published
- 2016
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38. Integrated, DC voltage-driven nucleic acid diagnostic platform for real sample analysis: Detection of oral cancer.
- Author
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Slouka Z, Senapati S, Shah S, Lawler R, Shi Z, Stack MS, and Chang HC
- Subjects
- Biomarkers, Tumor analysis, Systems Integration, Electric Conductivity, Lab-On-A-Chip Devices economics, MicroRNAs analysis, Mouth Neoplasms diagnosis
- Abstract
We present an integrated and low-cost microfluidic platform capable of extraction of nucleic acids from real biological samples. We demonstrate the application of this platform in pathogen detection and cancer screening. The integrated platform consists of three units including a pretreatment unit for separation of nucleic acids from lysates, a preconcentration unit for concentration of isolated nucleic acids and a sensing unit localized at a designated position on the chip for specific detection of the target nucleic acid. The platform is based on various electrokinetic phenomena exhibited by ion exchange membranes in a DC electrical field that allow them to serve as molecular filters, analyte preconcentrators and sensors. In this manuscript, we describe each unit of the integrated chip separately and show specific detection of a microRNA (miRNA 146a) biomarker associated with oral cancer as a proof-of-concept experiment. This platform technology can easily be extended to other targets of interest by optimizing the properties of the ion exchange membranes and the specific probes functionalized onto the sensors., (Copyright © 2015 Elsevier B.V. All rights reserved.)
- Published
- 2015
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39. Development and optimization of press coated tablets of release engineered valsartan for pulsatile delivery.
- Author
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Shah S, Patel R, Soniwala M, and Chavda J
- Subjects
- Angiotensin II Type 1 Receptor Blockers chemistry, Calorimetry, Differential Scanning, Cellulose analogs & derivatives, Cellulose chemistry, Chemistry, Pharmaceutical methods, Circadian Rhythm physiology, Delayed-Action Preparations, Drug Compounding methods, Drug Liberation, Hypromellose Derivatives chemistry, Pulse Therapy, Drug, Solubility, Spectroscopy, Fourier Transform Infrared, Tablets, Time Factors, Valsartan chemistry, Angiotensin II Type 1 Receptor Blockers administration & dosage, Excipients chemistry, Valsartan administration & dosage, beta-Cyclodextrins chemistry
- Abstract
The present work is aimed to develop and optimize pulsatile delivery during dissolution of an improved formulation of valsartan to coordinate the drug release with circadian rhythm. Preliminary studies suggested that β cyclodextrin could improve the solubility of valsartan and showed AL type solubility curve. A 1:1 stoichiometric ratio of valsartan to β cyclodextrin was revealed from phase solubility studies and Job's plot. The prepared complex showed significantly better dissolution efficiency (p < 0.05) compared to pure drug, which could be due to the formation of inclusion complex as revealed from FTIR and DSC studies. Continuous dissolution-absorption studies revealed that absorption of drug from valsartan β cyclodextrin complex was significantly higher (p < 0.05) compared to pure drug, in second part press-coated tablets of valsartan β cyclodextrin complex were subsequently prepared and application of the Plackett-Burman screening design revealed that HPMC K4M and EC showed significant effect on lag time. A 3(2) full factorial design was used to measure the response of HPMC K4M and EC on lag time and time taken for 90% drug release (T90). The optimized batch prepared according to the levels obtained from the desirability function had a lag time of 6 h and consisted of HPMC K4M:ethylcellulose in a 1:1.5 ratio with 180 mg of coating and revealed a close agreement between observed and predicted value (R(2 )= 0.9694).
- Published
- 2015
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40. Success with men's educational group appointments (MEGA): subjective improvements in patient education.
- Author
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Campbell BB, Shah S, and Gosselin D
- Subjects
- Adult, Age Factors, Aged, Attitude to Health, Health Behavior, Humans, Male, Mass Screening organization & administration, Massachusetts, Middle Aged, Patient Compliance, Program Development, Program Evaluation, Risk Assessment, Young Adult, Men's Health, Patient Education as Topic organization & administration, Patient Satisfaction, Preventive Health Services organization & administration
- Abstract
Men have a higher age-adjusted death rate from many of the leading causes of death, compared with women. Avoidance of health care and unhealthy behavior contribute to premature death among men. The Lahey Clinic recently initiated a program, the Men's Educational Group Appointment (MEGA), which capitalizes on the potential benefits of group dynamics in an effort to educate men about preventative health. We hypothesized that putting men into a group setting for the educational portion of the visit would improve information exchange and patient learning. During 12 months, 261 men between the ages of 22 and 67 were evaluated. A survey designed to address both patient satisfaction and patients' perceptions regarding how much they learned was administered to all patients following the MEGA session. We identified high patient satisfaction with the MEGA model. This study illustrates the potential utility of the group model for improving patient education regarding health maintenance among men.
- Published
- 2009
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41. Design, development, and optimization of orally disintegrating tablets of etoricoxib using vacuum-drying approach.
- Author
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Patel D, Shah M, Shah S, Shah T, and Amin A
- Subjects
- Administration, Oral, Camphor chemistry, Cellulose analogs & derivatives, Cellulose chemistry, Desiccation, Etoricoxib, Linear Models, Models, Theoretical, Tablets, Vacuum, Cyclooxygenase Inhibitors chemistry, Excipients chemistry, Pyridines chemistry, Sulfones chemistry
- Abstract
Etoricoxib is a cyclooxygenase 2 (COX-2) inhibitor that selectively inhibits the COX-2 enzyme and decreases the incidences of side effects associated with these agents. It is commonly prescribed for acute pain, gouty arthritis, and rheumatoid arthritis. Conventional tablets of etoricoxib are not capable of rapid action, which is required for faster drug effect onset and immediate relief from pain. Thus, the aim of the present investigation is to formulate orally disintegrating tablets (ODTs) of etoricoxib. A combination of the superdisintegrants with a sublimation technique was used to prepare the tablets. Tablets were prepared using a direct compression method employing superdisintegrants such as low substituted hydroxylpropyl methyl cellulose (L-HPMC), low substituted hydroxyl-propyl cellulose (L-HPC), crospovidone, croscarmellose sodium, and sodium starch glycolate. Tablets of etoricoxib prepared using L-HPC exhibited the least friability and disintegration time (approximately 65 s). To decrease the disintegration time further, a sublimation technique was used along with the superdisintegrants for the preparation of ODTs. The use of sublimating agents including camphor, menthol, and thymol was explored. The addition of camphor lowered the disintegration time (approximately 30 s) further, but the percent friability was increased. A 3(2) full factorial design was employed to study the joint influence of the amount of superdisintegrant (L-HPC) and the amount of sublimating agent (camphor) on the percent of friability and the disintegration time. The results of multiple linear regression analysis revealed that for obtaining an effective ODT of etoricoxib, higher percentages of L-HPC and camphor should be used. Checkpoint batches were prepared to validate the evolved mathematical model. A response surface plot is also presented to graphically represent the effect of the independent variables on the percent of friability and the disintegration time. The approach using the optimization technique helped to produce a detailed understanding of the effects of formulation parameters.
- Published
- 2008
42. Patterning cells on optically transparent indium tin oxide electrodes.
- Author
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Shah S and Revzin A
- Subjects
- Animals, Cell Adhesion physiology, Glass, Humans, Polyethylene Glycols, Cell Communication physiology, Microelectrodes, Tin Compounds
- Abstract
The ability to exercise precise spatial and temporal control over cell-surface interactions is an important prerequisite to the assembly of multi-cellular constructs serving as in vitro mimics of native tissues. In this study, photolithography and wet etching techniques were used to fabricate individually addressable indium tin oxide (ITO) electrodes on glass substrates. The glass substrates containing ITO microelectrodes were modified with poly(ethylene glycol) (PEG) silane to make them protein and cell resistive. Presence of insulating PEG molecules on the electrode surface was verified by cyclic voltammetry employing potassium ferricyanide as a redox reporter molecule. Importantly, the application of reductive potential caused desorption of the PEG layer, resulting in regeneration of the conductive electrode surface and appearance of typical ferricyanide redox peaks. Application of reductive potential also corresponded to switching of ITO electrode properties from cell non-adhesive to cell-adhesive. Electrochemical stripping of PEG-silane layer from ITO microelectrodes allowed for cell adhesion to take place in a spatially defined fashion, with cellular patterns corresponding closely to electrode patterns. Micropatterning of several cell types was demonstrated on these substrates. In the future, the control of the biointerfacial properties afforded by this method will allow to engineer cellular microenvironments through the assembly of three or more cell types into a precise geometric configuration on an optically transparent substrate.
- Published
- 2007
- Full Text
- View/download PDF
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