663 results on '"Deepak Srivastava"'
Search Results
102. STUDIES ON MECHANICAL AND THERMAL PROPERTIES OF EPOXY/FLY ASH/NANOFILLER NANOCOMPOSITE: A REVIEW
- Author
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Shilpi Tiwari, C. L. Gehlot, Kavita Srivastava, and Deepak Srivastava
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Materials science ,Nanocomposite ,Control and Systems Engineering ,Computer Networks and Communications ,visual_art ,Fly ash ,Thermal ,visual_art.visual_art_medium ,Building and Construction ,Epoxy ,Composite material ,Civil and Structural Engineering - Published
- 2020
103. Rapid Modulation of Spinogenesis by Estradiol in the Neocortex
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Deepak Srivastava, Katherine J. Sellers, and Peter D. Evans
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Neocortex ,medicine.anatomical_structure ,Chemistry ,Modulation ,medicine ,Neuroscience ,GPER ,hormones, hormone substitutes, and hormone antagonists - Abstract
This chapter explores our recent advances in our understanding of how estrogens can modulate spinogenesis within the cortex and its relevance for estrogenic-regulation of cognition. It describes how estrogens, including 17β-estradiol and estrogen receptor modulators, rapidly modify dendritic spine density concurrently with influencing cognitive behaviors that require cortical processing. Furthermore, it reviews the evidence that these effects are not limited to female animals but may represent a relevant mechanism in the male brain. This chapter will also explore the emerging role for a novel estrogen receptor, G-protein estrogen receptor (GPER), in mediating the rapid effects of estrogens on dendritic spines. Finally, the chapter also reviews the potential molecular mechanisms that underlie rapid estrogenic signaling, linking this signaling to the modulation of spinogenesis, which may ultimately provide a cellular model by which estrogens can produce long-lasting changes in neural circuitry.
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- 2020
104. Estradiol reverses excitatory synapse loss in a cellular model of neuropsychiatric disorders
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Peter Penzes, Pooja Raval, Alish B. Palmos, Nicholas J. Brandon, Nicholas J.F. Gatford, Deepak Srivastava, Stephen J. Moss, Filippo Erli, Katherine J. Sellers, and Jayanta Mukherjee
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Cellular pathology ,Dendritic spine ,Dendritic Spines ,Molecular neuroscience ,Article ,lcsh:RC321-571 ,03 medical and health sciences ,Cellular and Molecular Neuroscience ,DISC1 ,Glutamatergic ,0302 clinical medicine ,Excitatory synapse ,medicine ,Humans ,lcsh:Neurosciences. Biological psychiatry. Neuropsychiatry ,Biological Psychiatry ,030304 developmental biology ,Depressive Disorder, Major ,0303 health sciences ,Estradiol ,biology ,Estrogens ,medicine.disease ,3. Good health ,Psychiatry and Mental health ,Schizophrenia ,Synapses ,biology.protein ,Excitatory postsynaptic potential ,Ectopic expression ,Cellular model ,Psychiatric disorders ,Neuroscience ,030217 neurology & neurosurgery - Abstract
Loss of glutamatergic synapses is thought to be a key cellular pathology associated with neuropsychiatric disorders including schizophrenia (SCZ) and major depressive disorder (MDD). Genetic and cellular studies of SCZ and MDD using in vivo and in vitro systems have supported a key role for dysfunction of excitatory synapses in the pathophysiology of these disorders. Recent clinical studies have demonstrated that the estrogen, 17β-estradiol can ameliorate many of the symptoms experienced by patients. Yet, to date, our understanding of how 17β-estradiol exerted these beneficial effects is limited. In this study, we have tested the hypothesis that 17β-estradiol can restore dendritic spine number in a cellular model that recapitulates the loss of synapses associated with SCZ and MDD. Ectopic expression of wildtype, mutant or shRNA-mediated knockdown of Disrupted in Schizophrenia (DISC1) reduced dendritic spine density in primary cortical neurons. Acute or chronic treatment with 17β-estradiol increased spine density to control levels in neurons with altered DISC1 levels. In addition, 17β-estradiol reduced the extent to which ectopic wildtype and mutant DISC1 aggregated. Furthermore, 17β-estradiol also caused the enrichment of synaptic proteins at synapses and increased the number of dendritic spines containing PSD-95 or that overlapped with the pre-synaptic marker bassoon. Taken together, our data indicates that estrogens can restore lost excitatory synapses caused by altered DISC1 expression, potentially through the trafficking of DISC1 and its interacting partners. These data highlight the possibility that estrogens exert their beneficial effects in SCZ and MDD in part by modulating dendritic spine number.
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- 2020
105. Integration of Protein Interactome Networks With Congenital Heart Disease Variants Reveals Candidate Disease Genes
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Franco Felix, Casey A. Gifford, Kaitlen Samse-Knapp, Elisabetta Moroni, Bonnie Cole, Michael Alexanian, Maureen Pittman, Bruce D. Gelb, Deepak Srivastava, Benoit G. Bruneau, Michael McGregor, Bruce R. Conklin, Bárbara González-Terán, Ruth Hüttenhain, Giorgio Colombo, Katherine S. Pollard, Desmond Richmond-Buccola, Krishna Choudhary, Nevan J. Krogan, Brian L. Black, and Reuben Thomas
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Proband ,Heart disease ,GATA4 ,medicine ,Missense mutation ,Disease ,Epigenetics ,Computational biology ,Biology ,medicine.disease ,Interactome ,Gene - Abstract
Congenital heart disease (CHD) is present in 1% of live births, yet identification of causal mutations remains a challenge despite large-scale genomic sequencing efforts. We hypothesized that genetic determinants for CHDs may lie in protein interactomes of GATA4 and TBX5, two transcription factors that cause CHDs. Defining their interactomes in human cardiac progenitors via affinity purification-mass spectrometry and integrating results with genetic data from the Pediatric Cardiac Genomic Consortium revealed an enrichment of de novo variants among proteins that interact with GATA4 or TBX5. A consolidative score that prioritized interactome members based on variant, gene, and proband features identified likely CHD-causing genes, including the epigenetic reader GLYR1. GLYR1 and GATA4 widely co-occupied cardiac developmental genes, resulting in co-activation, and the GLYR1 missense variant associated with CHD disrupted interaction with GATA4. This integrative proteomic and genetic approach provides a framework for prioritizing and interrogating the contribution of genetic variants in disease.
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- 2020
106. Transcriptome-Wide Association Study Reveals Two Genes that Influence Mismatch Negativity
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Deepak Srivastava, Karl J. Friston, Patricio O'Donnell, Eirini Zartaloudi, Isabelle Austin-Zimmerman, Rick A. Adams, Elvira Bramon, Anjali Bhat, Johan H. Thygesen, Ann Summerfelt, L. Elliot Hong, Xiaoming Michael Du, Rebecca Muir, Baihan Wang, Oliver Pain, Jasmine Harju-Seppänen, Heather Bruce, Mei-Hua Hall, Karoline Kuchenbaecker, and Haritz Irizar
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Psychosis ,Sensory processing ,medicine.medical_treatment ,Mismatch negativity ,Biology ,medicine.disease ,behavioral disciplines and activities ,Cortex (botany) ,Transcriptome ,Electrophysiology ,Endophenotype ,medicine ,Association (psychology) ,Neuroscience ,psychological phenomena and processes - Abstract
Mismatch negativity (MMN) is a differential electrophysiological response measuring cortical adaptability to unpredictable stimuli. MMN is consistently attenuated in patients with psychosis. However, the genetics of MMN are uncharted, limiting the validation of MMN as a psychosis endophenotype. We therefore performed a transcriptome-wide association study of 728 individuals, which revealed two genes (FAM89A and ENGASE) whose expression in cortical tissues is associated with MMN. Enrichment analyses of neurodevelopmental expression signatures showed that genes associated with MMN tend to be overexpressed in frontal cortex during prenatal development but significantly downregulated in adulthood. In our Endophenotype Ranking Value calculation comparing MMN and three other candidate psychosis endophenotypes (lateral ventricular volume and two auditory-verbal learning measures), MMN was considerably superior. These results yield promising insights into sensory processing in the cortex and endorse the notion of MMN as a psychosis endophenotype.
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- 2020
107. Epoxy/Fly ash from Thermal Power Plant/Nanofiller Nanocomposite: Studies on Mechanical and Thermal Properties: A Review
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Shilpi Tiwari, Deepak Srivastava, C. L. Gehlot, and Kavita Srivastava
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Nanocomposite ,Materials science ,Thermal resistance ,Izod impact strength test ,02 engineering and technology ,Epoxy ,010501 environmental sciences ,engineering.material ,021001 nanoscience & nanotechnology ,01 natural sciences ,Flexural strength ,visual_art ,Fly ash ,Filler (materials) ,Ultimate tensile strength ,visual_art.visual_art_medium ,engineering ,Composite material ,0210 nano-technology ,0105 earth and related environmental sciences - Abstract
A recent development in the field of eco-friendly, lightweight and high-performance nanocomposite and a broad range of their innovative applications attract enormous interest in the field of research. However, the search for lighter materials to replace legacy heavy materials in engineering structures especially in automobile and aerospace industries has made the study of tribological properties of epoxy resin based composites significant. Fly ash, from the thermal power plant, is an industrial by-product that can be utilized as filler in epoxy resin with different wt% owing to its distinctive properties like low density, wide availability, good filler factor, good thermal resistance, and glassy nature instead of dumping into the large area of landfills and ash ponds. This review article presents an expanded literature overview on the utilization of industrial waste fly ash, as reinforcement for matrix in making lightweight, high strength composites. In this investigation broaden literature groundwork also covers the effect of nanoparticles on thermal, morphological and mechanical characteristics such as impact strength, tensile strength and flexural strength of fly ash/epoxy nanocomposites.
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- 2020
108. Investigations on Reactive Extraction of Butyric Acid Using Tri-n-Octyl Amine in Various Biodiesels
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Diwakar Z. Shende, Deepak Srivastava, Ashwani Kumar Rathore, Shivam Kumar, Vikrant Singh, Shourabh Singh Raghuwanshi, and Sunder Lall Pal
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Biodiesel ,food.ingredient ,Chromatography ,Chemistry ,Sunflower oil ,Extraction (chemistry) ,Rice bran oil ,food and beverages ,Raw material ,Partition coefficient ,Butyric acid ,chemistry.chemical_compound ,food ,Fermentation - Abstract
Butyric acid is a monocarboxylic acid which can be produced economically by fermentation from green feedstock. As the recovery of butyric acid from dilute fermentation broth is a challenge and hence it needs to develop a competitive downstream recovery process. Butyric acid finds a wide range of applications in pharmaceutical, food, cosmetics and power industries. Reactive extraction is one of the most promising and accessible methods which can be used as first separation step for recovery of butyric acid from dilute wastewater stream or fermentation broth. In present study, the physical and reactive extraction of butyric acid using tri-n-octylamine (TOA) in biodiesel made from sesame oil, rice bran oil, karanja oil and sunflower oil were studied at 298K and comparatively found the reactive extraction as more efficient. The Partition coefficient P, dimerization constant D and the distribution coefficient KD were obtained in the physical extraction study. In reactive extraction, the results were obtained in terms of distribution coefficient KD, loading ratio O and the degree of extraction E%.
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- 2020
109. Thermal and mechanical characterization of alumina modified multifunctional novolac epoxy nanocomposites
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Archana Mishra, Moksh Shukla, Manoj K Shukla, Deepak Srivastava, and Arun K Nagpal
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Polymers and Plastics ,Materials Chemistry ,Ceramics and Composites - Abstract
The multifunctional novolac epoxy/Al2O3 nanocomposites were fabricated by high-speed mechanical mixing of epoxy resin with varying concentration of nano Al2O3 (0–5 wt%) of particle size 13 nm for 30 min, followed by curing with triethylenetetramine (TETA) at 110°C for 1 h and post-curing at 80°C for 5 h. The fabricated nanocomposite samples were characterized for mechanical properties (viz., tensile strength, elongation-at-break, impact strength, toughness, and hardness shore D), thermal stability, and fire retardancy. It was observed that the 3 wt% nano-Al2O3 containing sample showed significant enhancement in the tensile strength, elongation-at-break, impact strength, hardness shore D, thermal stability, and fire retardancy compared to the neat epoxy sample. The Differential Scanning calorimetry (DSC) confirmed the 3-D curing reaction between TETA and nano-alumina modified epoxy and neat epoxy samples. The reactivity effect of alumina towards resin was investigated by Fourier Transform Infrared (FTIR) spectroscopy. The morphological studies of nanocomposite samples were investigated by Scanning Electron Microscopy (SEM) to justify the enhancement of mechanical properties via dispersion of nanoparticles.
- Published
- 2022
110. Author response for 'Brain‐synthesized estrogens regulate cortical migration in a sexually divergent manner'
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Atsushi Saito, Irene Salgarella, Deepak Srivastava, Katherine J. Sellers, Matthew C.S. Denley, Alessio Delogu, Atsushi Kamiya, and Evangeline M. Foster
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- 2019
111. The Himalayan cryosphere: past and present variability of the ‘third pole’
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Lonnie G. Thompson, Deepak Srivastava, Naresh Chandra Pant, and Rasik Ravindra
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010504 meteorology & atmospheric sciences ,Cryosphere ,Geology ,Ocean Engineering ,Physical geography ,010502 geochemistry & geophysics ,01 natural sciences ,0105 earth and related environmental sciences ,Water Science and Technology - Published
- 2018
112. Reactive Extraction of Caproic Acid using Tri-n- Butyl Phosphate (TBP) in Non Toxic Diluents
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Diwakar Z. Shende, Ashwani Kumar Rathore, Kailas L. Wasewar, and Deepak Srivastava
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020401 chemical engineering ,Chemistry ,General Chemical Engineering ,Extraction (chemistry) ,Tri-N-butyl Phosphate ,02 engineering and technology ,General Chemistry ,0204 chemical engineering ,021001 nanoscience & nanotechnology ,0210 nano-technology ,Diluent ,Caproic Acid ,Nuclear chemistry - Published
- 2018
113. Publisher Correction: BRD4 orchestrates genome folding to promote neural crest differentiation
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Rajan Jain, Haoyue Zhang, Parisha P. Shah, Li Li, Wonho Kim, Nikhita A. Bolar, Qiaohong Wang, Ricardo Linares-Saldana, Jennifer M. Luppino, Bailey A Koch-Bojalad, Arun Padmanabhan, Gwang Hyeon Eom, Cheryl L. Smith, Gerd A. Blobel, Deepak Srivastava, Sora Yoon, Eric F. Joyce, Golnaz Vahedi, Ashley Karnay, Andrey Poleshko, Danny S. Park, and Son C. Nguyen
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BRD4 ,Genetics ,Neural crest ,Computational biology ,Folding (DSP implementation) ,Biology ,Genome - Published
- 2021
114. Life enhancement of Nozzle Guide Vane of an Aero Gas Turbine Engine through Pack Aluminization
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K. Rajesh, Ganapathi Sharma, Prashant Kumar, C R Das, R. K. Mishra, and Deepak Srivastava
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Gas turbines ,020303 mechanical engineering & transports ,Materials science ,0203 mechanical engineering ,020209 energy ,Nozzle ,0202 electrical engineering, electronic engineering, information engineering ,Aerospace Engineering ,Mechanical engineering ,02 engineering and technology - Abstract
Pack aluminization of high pressure turbine nozzle guide vane of an aero gas turbine engine has been carried out following a well defined systematic procedure. The process parameters are first optimized on dummy vanes and optimized process is followed for the actual vanes for evaluation and testing. Visual and binocular examination followed by metallurgical evaluation have been carried out to validate the process and to establish the adequacy and correctness of the coating. The coated vanes are then evaluated through engine level tests for performance and durability. The results of engine level tests and inspection post accelerated mission test cycles ensure that the vanes with aluminide coating can withstand severe engine operating cycles without any damage or failure which would otherwise would have happened without the coating. The condition of vanes post endurance test is also an indication of enhanced life of the vanes with coating.
- Published
- 2017
115. W73. SUPPRESSION OF THE INFLAMMATORY RESPONSE IN SCHIZOPHRENIA HIPSC-DERIVED NEURAL PROGENITORS: A GENE-ENVIRONMENT INTERACTION STUDY
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Roland Nagy, Pooja Raval, Timothy R. Powell, Elvira Bramon, Rodrigo R.R. Duarte, Anjali Bhat, Anthony C. Vernon, Aritz Irizar, Deepak Srivastava, and Lucia Dutan Polit
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Pharmacology ,Psychiatry and Mental health ,Neurology ,Inflammatory response ,Schizophrenia (object-oriented programming) ,Pharmacology (medical) ,Neurology (clinical) ,Biology ,Progenitor cell ,Neuroscience ,Gene ,Biological Psychiatry - Published
- 2021
116. TH8. ANALYSIS OF NRXN1 EXPRESSION DURING EARLY NEURONAL DIFFERENTIATION IN PATIENT-DERIVED INDUCED PLURIPOTENT STEM CELLS (IPSC) WITH ALTERED EXPRESSION OF NRXN1
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Deep Adhya, Roland Nagy, Deepak Srivastava, Lucia Dutan Polit, and Nick J. F. Gatford
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Pharmacology ,Psychiatry and Mental health ,Neurology ,Expression (architecture) ,Neuronal differentiation ,Pharmacology (medical) ,In patient ,Neurology (clinical) ,Biology ,Induced pluripotent stem cell ,Biological Psychiatry ,Cell biology - Published
- 2021
117. Magnetic fabrics in an apparently undeformed granite body near Main Boundary Thrust (MBT), Kumaun Lesser Himalaya, India
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Amar Agarwal, Jyoti Shah, Deepak Srivastava, and Manish A. Mamtani
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Lineation ,Tectonics ,Geophysics ,Basement (geology) ,Proterozoic ,Geochemistry ,Tectonic phase ,Orogeny ,Neogene ,Overprinting ,Geology ,Earth-Surface Processes - Abstract
The Amritpur Granite, sandwiched between the two intensely deformed rock packages, occurs adjacent to the Main Boundary Thrust (MBT) in the outer part of the Kumaun Lesser Himalaya. Characteristically, the granite lacks any penetrative tectonic fabric at the microscopic or mesoscopic scales. Using high-resolution mapping, litholog, and outcrop-scale overprinting relationships, we first revisit the tectonic setting of the Amritpur Granite and then attempt to detect the magnetic fabric, if any, in it. For this, we investigate the anisotropy of magnetic susceptibility in the Amritpur Granite and the adjacent lithounits deformed presumably during the Himalayan orogeny. High-resolution mapping demonstrates that the MBT traces the boundary between the Neogene Siwalik sediments and the Proterozoic amphibolite of the Nagthat Formation in the study area. Field relationships and structural setting imply that the granite occurs either as a probable klippe or a basement sliver. The orientations of the mesoscopic scale foliations and lineations are similar to the respective magnetic fabric orientations in the deformed lithounits occurring adjacent to the Amritpur Granite. The tectonically induced magnetic fabric orientations in the deformed lithounits also correlate well with the magnetic fabric orientations in the Amritpur Granite. Several lines of evidence suggest that the magnetic fabrics in the Amritpur Granite and those in the adjacent deformed lithounits were induced during a common deformation phase.
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- 2021
118. Mouse gastruloids take heart
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Deepak Srivastava and Todd C. McDevitt
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0301 basic medicine ,business.industry ,Cell ,Organogenesis ,030204 cardiovascular system & hematology ,Embryonic stem cell ,Cell biology ,03 medical and health sciences ,030104 developmental biology ,0302 clinical medicine ,medicine.anatomical_structure ,Organoid ,Medicine ,Cardiology and Cardiovascular Medicine ,business ,Ex vivo - Abstract
Mouse embryonic organoids that model cardiac development ex vivo could be used as a high-throughput, experimentally tractable system to evaluate crucial cell populations and environmental factors that contribute to normal and abnormal cardiogenesis.
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- 2021
119. P.540 Modelling the effects of maternal immune activation on early neurodevelopment using a human induced pluripotent stem cell derived system
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A. Couch, Anthony C. Vernon, Deepak Srivastava, Laura Sichlinger, and B. Hanger
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Pharmacology ,Psychiatry and Mental health ,Neurology ,Pharmacology (medical) ,Neurology (clinical) ,Biology ,Induced pluripotent stem cell ,Biological Psychiatry ,Immune activation ,Cell biology - Published
- 2020
120. Simulation of the thermal degradation and curing kinetics of fly ash reinforced diglycidyl ether bisphenol A composite
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Deepak Srivastava, Shilpi Tiwari, C. L. Gehlot, and Kavita Srivastava
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Thermogravimetric analysis ,Diglycidyl ether ,010405 organic chemistry ,Chemistry ,Organic Chemistry ,Kinetics ,Epoxy ,010402 general chemistry ,01 natural sciences ,0104 chemical sciences ,Inorganic Chemistry ,chemistry.chemical_compound ,Differential scanning calorimetry ,visual_art ,Fly ash ,Drug Discovery ,Electrochemistry ,visual_art.visual_art_medium ,Thermal stability ,Physical and Theoretical Chemistry ,Composite material ,Curing (chemistry) - Abstract
Thermogravimetric Analysis (TGA) is concluding expanding applicability in determination of the thermal stability and degradation nature of materials. The present study investigates the thermal degradation behavior and the kinetics of degradation of epoxy mixed with varying percentages of 0, 2.5, 5, and 7.5 wt% fly ash. Thermal stability and degradation behavior of fly ash modified epoxy cast were determined by thermogravimetric analysis. The kinetic parameters of the EF composites were calculated by using Coats–Redfern, Broido and Horowitz–Metzger models under best-fit analysis and further proved by linear regression analysis. The kinetics of thermal degradation was calculated from data scanned at a heating rate of 10 °C/min. The obtained results reveal that kinetic parameters and thermal behavior of EF composites were improved with the reinforcement of fly ash. The cure kinetics of the varying content of fly ash reinforced epoxy cast were also studied by using a nonisothermal differential scanning calorimetric (DSC) technique at four different heating rates 5 °C/min, 10 °C/min, 15 °C/min and 20 °C/min. The curing kinetics of the EF composite was derived from the nonisothermal differential scanning calorimetry (DSC) data with the three Kissinger, Ozawa, and Flynn–Wall–Ozawa models, respectively.
- Published
- 2021
121. Effects of chronic exposure to haloperidol, olanzapine or lithium on SV2A and NLGN synaptic puncta in the rat frontal cortex
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Marie-Caroline Cotel, Deepak Srivastava, Els F. Halff, Oliver D. Howes, R McQuade, Anthony C. Vernon, Sridhar Natesan, and Chris J. Ottley
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Male ,Olanzapine ,medicine.medical_specialty ,Lithium (medication) ,Cell Adhesion Molecules, Neuronal ,medicine.medical_treatment ,Prefrontal Cortex ,Nerve Tissue Proteins ,Neuroligin ,Gyrus Cinguli ,Rats, Sprague-Dawley ,03 medical and health sciences ,Behavioral Neuroscience ,0302 clinical medicine ,Antimanic Agents ,Postsynaptic potential ,Internal medicine ,medicine ,Haloperidol ,Animals ,Antipsychotic ,Anterior cingulate cortex ,030304 developmental biology ,SV2A ,0303 health sciences ,Membrane Glycoproteins ,business.industry ,Rats ,Disease Models, Animal ,medicine.anatomical_structure ,Endocrinology ,Synapses ,Lithium Compounds ,Schizophrenia ,business ,030217 neurology & neurosurgery ,Antipsychotic Agents ,medicine.drug - Abstract
Positron emission tomography studies using the synaptic vesicle glycoprotein 2A (SV2A) radioligand [11C]-UCB-J provide in vivo evidence for synaptic dysfunction and/or loss in the cingulate and frontal cortex of patients with schizophrenia. In exploring potential confounding effects of antipsychotic medication, we previously demonstrated that chronic (28-day) exposure to clinically relevant doses of haloperidol does not affect [3H]-UCB-J radioligand binding in the cingulate and frontal cortex of male rats. Furthermore, neither chronic haloperidol nor olanzapine exposure had any effect on SV2A protein levels in these brain regions. These data do not exclude the possibility, however, that more subtle changes in SV2A may occur at pre-synaptic terminals, or the post-synaptic density, following chronic antipsychotic drug exposure. Moreover, relatively little is known about the potential effects of psychotropic drugs other than antipsychotics on SV2A. To address these questions directly, we herein used immunostaining and confocal microscopy to explore the effect of chronic (28-day) exposure to clinically relevant doses of haloperidol, olanzapine or the mood stabilizer lithium on presynaptic SV2A, postsynaptic Neuroligin (NLGN) puncta and their overlap as a measure of total synaptic density in the rat prefrontal and anterior cingulate cortex. We found that, under the conditions tested here, exposure to antipsychotics had no effect on SV2A, NLGN, or overall synaptic puncta count. In contrast, chronic lithium exposure significantly increased NLGN puncta density relative to vehicle, with no effect on either SV2A or total synaptic puncta. Future studies are required to understand the functional consequences of these changes.
- Published
- 2021
122. Estradiol modulates the efficacy of synaptic inhibition by decreasing the dwell time of GABA A receptors at inhibitory synapses
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Shiva K. Tyagarajan, Yasmine Cantaut-Belarif, Ross A. Cardarelli, Deepak Srivastava, Stephen J. Moss, Jayanta Mukherjee, Antoine Triller, Tarek Z. Deeb, Jamie Maguire, Nicholas J. Brandon, and Menelas N. Pangalos
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0301 basic medicine ,Multidisciplinary ,Gephyrin ,biology ,GABAA receptor ,Hippocampal formation ,Neurotransmission ,Inhibitory postsynaptic potential ,Synapse ,03 medical and health sciences ,030104 developmental biology ,0302 clinical medicine ,Postsynaptic potential ,biology.protein ,Excitatory postsynaptic potential ,Neuroscience ,030217 neurology & neurosurgery - Abstract
Estrogen plays a critical role in many physiological processes and exerts profound effects on behavior by regulating neuronal excitability. While estrogen has been established to exert effects on dendritic morphology and excitatory neurotransmission its role in regulating neuronal inhibition is poorly understood. Fast synaptic inhibition in the adult brain is mediated by specialized populations of γ-c aA receptors (GABAARs) that are selectively enriched at synapses, a process dependent upon their interaction with the inhibitory scaffold protein gephyrin. Here we have assessed the role that estradiol (E2) plays in regulating the dynamics of GABAARs and stability of inhibitory synapses. Treatment of cultured cortical neurons with E2 reduced the accumulation of GABAARs and gephyrin at inhibitory synapses. However, E2 exposure did not modify the expression of either the total or the plasma membrane GABAARs or gephyrin. Mechanistically, single-particle tracking revealed that E2 treatment selectively reduced the dwell time and thereby decreased the confinement of GABAARs at inhibitory synapses. Consistent with our cell biology measurements, we observed a significant reduction in amplitude of inhibitory synaptic currents in both cultured neurons and hippocampal slices exposed to E2, while their frequency was unaffected. Collectively, our results suggest that acute exposure of neurons to E2 leads to destabilization of GABAARs and gephyrin at inhibitory synapses, leading to reductions in the efficacy of GABAergic inhibition via a postsynaptic mechanism.
- Published
- 2017
123. DGEBA Epoxy/CaCO 3 Nanocomposites for Improved Chemical Resistance and Mechanical Properties for Coating Applications
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Anita Rathore, Kavita Srivastava, Manoj Kumar Shukla, Archana Mishra, and Deepak Srivastava
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Chemical resistance ,Materials science ,Nanocomposite ,Resin matrix ,Coating ,visual_art ,engineering ,visual_art.visual_art_medium ,Epoxy ,engineering.material ,Composite material - Published
- 2017
124. Contribution of rare inherited and de novo variants in 2,871 congenital heart disease probands
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Cecelia W. Lo, Stephen Sanders, Sarah U. Morton, Irina R. Tikhonoa, Samir Zaidi, Elizabeth Goldmuntz, Hongjian Qi, Richard B. Kim, Jonathan R. Kaltman, Jonathan G. Seidman, Xue Zeng, Jason Homsy, George A. Porter, W. Scott Watkins, Deepak Srivastava, Weni Chang, Martin Tristani-Firouzi, Seema Mital, James R. Knight, Qiongshi Lu, Steven R. DePalma, John E. Deanfield, Christopher Castaldi, J. William Gaynor, Yufeng Shen, Bruce D. Gelb, Mark W. Russell, Richard P. Lifton, Alessandro Giardini, Kaya Bilguvar, Wendy K. Chung, Jane W. Newburger, H. Joseph Yost, Sheng Chih Jin, Mark Yandell, Martina Brueckner, Shrikant Mane, Robert D. Bjornson, Wei Chien Hung, Amy E. Roberts, Junhui Zhang, Christine E. Seidman, Michael C. Sierant, Hongyu Zhao, and Shozeb Haider
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Heart Defects, Congenital ,Risk ,Adult ,Male ,0301 basic medicine ,Proband ,Heterozygote ,Heart disease ,Gene Expression ,Genome-wide association study ,Biology ,Medical and Health Sciences ,Article ,Growth Differentiation Factor 1 ,Congenital ,03 medical and health sciences ,Genotype ,Genetics ,medicine ,Humans ,Genetic Predisposition to Disease ,Exome ,cardiovascular diseases ,Autistic Disorder ,Child ,Exome sequencing ,Heart Defects ,Tetralogy of Fallot ,Myosin Heavy Chains ,Homozygote ,Case-control study ,High-Throughput Nucleotide Sequencing ,Biological Sciences ,Vascular Endothelial Growth Factor Receptor-3 ,medicine.disease ,Pedigree ,3. Good health ,Editorial ,030104 developmental biology ,Case-Control Studies ,Mutation ,Female ,Cardiac Myosins ,Genome-Wide Association Study ,Developmental Biology - Abstract
Congenital heart disease (CHD) is the leading cause of mortality from birth defects. Here, exome sequencing of a single cohort of 2,871 CHD probands, including 2,645 parent-offspring trios, implicated rare inherited mutations in 1.8%, including a recessive founder mutation in GDF1 accounting for ∼5% of severe CHD in Ashkenazim, recessive genotypes in MYH6 accounting for ∼11% of Shone complex, and dominant FLT4 mutations accounting for 2.3% of Tetralogy of Fallot. De novo mutations (DNMs) accounted for 8% of cases, including ∼3% of isolated CHD patients and ∼28% with both neurodevelopmental and extra-cardiac congenital anomalies. Seven genes surpassed thresholds for genome-wide significance, and 12 genes not previously implicated in CHD had >70% probability of being disease related. DNMs in ∼440 genes were inferred to contribute to CHD. Striking overlap between genes with damaging DNMs in probands with CHD and autism was also found.
- Published
- 2017
125. Stem cell-derived neurons from autistic individuals with SHANK3 mutation show morphogenetic abnormalities during early development
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Laura C. Andreae, Stefan Aigner, Nick J. F. Gatford, Deepak Srivastava, Annie Kathuria, Jack Price, Ravi Jagasia, Paulina Nowosiad, Ruth D. Taylor, and Walter Lucchesi
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0301 basic medicine ,Neurite ,Autism Spectrum Disorder ,Cellular differentiation ,Induced Pluripotent Stem Cells ,Nerve Tissue Proteins ,Biology ,Synaptic Transmission ,Cell Line ,03 medical and health sciences ,Cellular and Molecular Neuroscience ,0302 clinical medicine ,Neural Stem Cells ,Humans ,Induced pluripotent stem cell ,Molecular Biology ,Cells, Cultured ,Genetics ,Neurons ,Excitatory Postsynaptic Potentials ,Post-Synaptic Density ,Cell Differentiation ,Embryonic stem cell ,Phenotype ,Neural stem cell ,Cell biology ,Psychiatry and Mental health ,030104 developmental biology ,Cell culture ,Mutation ,Synapses ,Original Article ,Stem cell ,Chromosome Deletion ,030217 neurology & neurosurgery - Abstract
Shank3 is a structural protein found predominantly at the post-synaptic density. Mutations in the SHANK3 gene have been associated with risk for autism spectrum disorder (ASD). We generated induced pluripotent stem cells (iPSCs) from control individuals and from human donors with ASD, carrying microdeletions of SHANK3. In addition, we used Zinc finger nucleases to generate isogenic SHANK3 knockout human embryonic stem (ES) cell lines. We differentiated pluripotent cells into either cortical or olfactory placodal neurons. We show that patient-derived placodal neurons make fewer synapses than control cells. Moreover, patient-derived cells display a developmental phenotype: young post-mitotic neurons have smaller cell bodies, more extensively branched neurites, and reduced motility compared with controls. These phenotypes were mimicked by SHANK3-edited ES cells, and rescued by transduction with a Shank3 expression construct. This developmental phenotype is not observed in the same iPSC lines differentiated into cortical neurons. Therefore, we suggest that SHANK3 plays a critical role in neuronal morphogenesis in placodal neurons, and that early defects are associated with ASD-associated mutations.
- Published
- 2017
126. Multi-Imaging Method to Assay the Contractile Mechanical Output of Micropatterned Human iPSC-Derived Cardiac Myocytes
- Author
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Bruce R. Conklin, Beth L. Pruitt, Yen-Sin Ang, Mohammad A. Mandegar, Alexandre J.S. Ribeiro, Deepak Srivastava, and Olivier Schwab
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0301 basic medicine ,Cardiac function curve ,Future studies ,Physiology ,Cells ,Induced Pluripotent Stem Cells ,Clinical Sciences ,cardiac myocyte ,Bioengineering ,Cardiac activity ,Cardiorespiratory Medicine and Haematology ,030204 cardiovascular system & hematology ,Cardiovascular ,Multimodal Imaging ,contractility ,Sarcomere ,Article ,03 medical and health sciences ,0302 clinical medicine ,Humans ,Myocyte ,Myocytes, Cardiac ,Induced pluripotent stem cell ,Cells, Cultured ,Myocytes ,sarcomere length ,Cultured ,Stem Cell Research - Induced Pluripotent Stem Cell - Human ,Stem Cell Research - Induced Pluripotent Stem Cell ,Chemistry ,Stem Cell Research ,Myocardial Contraction ,single cell ,stem cell ,Heart Disease ,030104 developmental biology ,Cardiovascular System & Hematology ,Cardiology and Cardiovascular Medicine ,Myofibril ,Cardiac ,Biomedical engineering - Abstract
Rationale: During each beat, cardiac myocytes (CMs) generate the mechanical output necessary for heart function through contractile mechanisms that involve shortening of sarcomeres along myofibrils. Human-induced pluripotent stem cells (hiPSCs) can be differentiated into CMs (hiPSC-CMs) that model cardiac contractile mechanical output more robustly when micropatterned into physiological shapes. Quantifying the mechanical output of these cells enables us to assay cardiac activity in a dish. Objective: We sought to develop a computational platform that integrates analytic approaches to quantify the mechanical output of single micropatterned hiPSC-CMs from microscopy videos. Methods and Results: We micropatterned single hiPSC-CMs on deformable polyacrylamide substrates containing fluorescent microbeads. We acquired videos of single beating cells, of microbead displacement during contractions, and of fluorescently labeled myofibrils. These videos were independently analyzed to obtain parameters that capture the mechanical output of the imaged single cells. We also developed novel methods to quantify sarcomere length from videos of moving myofibrils and to analyze loss of synchronicity of beating in cells with contractile defects. We tested this computational platform by detecting variations in mechanical output induced by drugs and in cells expressing low levels of myosin-binding protein C. Conclusions: Our method can measure the cardiac function of single micropatterned hiPSC-CMs and determine contractile parameters that can be used to elucidate mechanisms that underlie variations in CM function. This platform will be amenable to future studies of the effects of mutations and drugs on cardiac function.
- Published
- 2017
127. The E3 ubiquitin ligase Nedd4/Nedd4L is directly regulated by microRNA 1
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Jun-yi Zhu, Irfan S. Kathiriya, Zhe Han, Bayardo I. Garay, Isabelle N. King, Kathryn N. Ivey, Amy Heidersbach, and Deepak Srivastava
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0301 basic medicine ,Nedd4 Ubiquitin Protein Ligases ,Ubiquitin-Protein Ligases ,Green Fluorescent Proteins ,Actin filament organization ,Notch signaling pathway ,NEDD4 ,macromolecular substances ,Biology ,Medical and Health Sciences ,03 medical and health sciences ,microRNA ,Gene expression ,Animals ,Drosophila Proteins ,Wings, Animal ,Phosphorylation ,3' Untranslated Regions ,Molecular Biology ,Body Patterning ,NEDD4L ,Receptors, Notch ,Embryonic heart ,Heart development ,fungi ,Ubiquitination ,Heart ,Cell Biology ,Biological Sciences ,Molecular biology ,Actins ,Cell biology ,Ubiquitin ligase ,Actin Cytoskeleton ,MicroRNAs ,Protein Transport ,Drosophila melanogaster ,Phenotype ,030104 developmental biology ,biology.protein ,Signal Transduction ,Research Article ,Developmental Biology - Abstract
miR-1 is a small noncoding RNA molecule that modulates gene expression in heart and skeletal muscle. Loss of Drosophila miR-1 produces defects in somatic muscle and embryonic heart development, which have been partly attributed to miR-1 directly targeting Delta to decrease Notch signaling. Here, we show that overexpression of miR-1 in the fly wing can paradoxically increase Notch activity independently of its effects on Delta. Analyses of potential miR-1 targets revealed that miR-1 directly regulates the 3′UTR of the E3 ubiquitin ligase Nedd4. Analysis of embryonic and adult fly heart revealed that the Nedd4 protein regulates heart development in Drosophila. Larval fly hearts overexpressing miR-1 have profound defects in actin filament organization that are partially rescued by concurrent overexpression of Nedd4. These results indicate that miR-1 and Nedd4 act together in the formation and actin-dependent patterning of the fly heart. Importantly, we have found that the biochemical and genetic relationship between miR-1 and the mammalian ortholog Nedd4-like (Nedd4l) is evolutionarily conserved in the mammalian heart, potentially indicating a role for Nedd4L in mammalian postnatal maturation. Thus, miR-1-mediated regulation of Nedd4/Nedd4L expression may serve to broadly modulate the trafficking or degradation of Nedd4/Nedd4L substrates in the heart.
- Published
- 2017
128. Strategic Performance Measurement Using Balanced Scorecard: A Case of Machine Tool Industry
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Anil Kshatriya, Vijay Dharmadhikari, Deepak Srivastava, and P. C. Basak
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Earnings before interest, taxes, depreciation, and amortization ,Process management ,HF5001-6182 ,Amortization (business) ,Strategy and Management ,0211 other engineering and technologies ,balanced scorecard ,02 engineering and technology ,financial perspective and strategy ,organizational learning ,ddc:650 ,0502 economics and business ,Management. Industrial management ,Revenue ,Business ,Operations management ,internal business process ,balanced lean index ,Strategy map ,021103 operations research ,Balanced scorecard ,Earnings ,business.industry ,Depreciation ,05 social sciences ,HD28-70 ,Organizational learning ,050203 business & management - Abstract
This paper focuses on implementation, monitoring, and application of balanced scorecard (BSC) techniques in an organization involved in providing machine tool solutions to the industrial sector. The growth of the company considered in real time constituted improvements of both top and bottom lines. In the industry under consideration, it was observed that in our company, the top line was steadily growing but not the bottom line. This is when we started getting down to brass tacks and strategically focusing on growth in overall profits of the company. This included growing revenues by improving of EBITDA (earnings before interests, taxes, depreciation, and amortization) and by increasing efficiency (i.e., cutting costs). These improvements were implemented by chalking out a comprehensive BSC designed to suit the machine tool industry. The four perspectives of the management, namely, internal business process, organizational learning, financial perspective, and customer perspective, have been considered lucidly and enunciate the parameters that affect the BSC very aptly. The BSC designed considered 9 objectives and 27 relative measures of these factors to quantify the various quantitative and qualitative dimensions that affect the company’s performance. A Balanced Lean Index (BL Score) was used to measure the results for company X.
- Published
- 2017
129. The genetic algorithm: A robust method for stress inversion
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Prithvi Thakur, Deepak Srivastava, and Pravin K. Gupta
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Mathematical optimization ,010504 meteorology & atmospheric sciences ,Cauchy stress tensor ,Survival of the fittest ,Crossover ,Stress inversion ,Geology ,Inversion (meteorology) ,010502 geochemistry & geophysics ,01 natural sciences ,Physics::Geophysics ,Nonlinear system ,Local optimum ,Linearization ,Algorithm ,0105 earth and related environmental sciences ,Mathematics - Abstract
The stress inversion of geological or geophysical observations is a nonlinear problem. In most existing methods, it is solved by linearization, under certain assumptions. These linear algorithms not only oversimplify the problem but also are vulnerable to entrapment of the solution in a local optimum. We propose the use of a nonlinear heuristic technique, the genetic algorithm, which searches the global optimum without making any linearizing assumption or simplification. The algorithm mimics the natural evolutionary processes of selection, crossover and mutation and, minimizes a composite misfit function for searching the global optimum, the fittest stress tensor. The validity and efficacy of the algorithm are demonstrated by a series of tests on synthetic and natural fault-slip observations in different tectonic settings and also in situations where the observations are noisy. It is shown that the genetic algorithm is superior to other commonly practised methods, in particular, in those tectonic settings where none of the principal stresses is directed vertically and/or the given data set is noisy.
- Published
- 2017
130. Alternating augite-plagioclase wedges in basement dolerites of Lockne impact structure, Sweden: A new shock wave-induced deformation feature
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Deepak Srivastava, Luis M. Alva-Valdivia, Boris Reznik, and Amar Agarwal
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010504 meteorology & atmospheric sciences ,Mineralogy ,engineering.material ,010502 geochemistry & geophysics ,01 natural sciences ,Basement ,Geophysics ,Augite ,Impact crater ,Space and Planetary Science ,engineering ,Cleavage (geology) ,Plagioclase ,Impact structure ,Dislocation ,Petrology ,Geology ,0105 earth and related environmental sciences ,Labradorite - Abstract
This paper reports peculiar alternating augite-plagioclase wedges in basement dolerites of Lockne impact structure, Sweden. The combined microscopic and spectroscopic studies of the micro/nanoscale wedges reveal that these are deformation-induced features. First, samples showing wedges, 12 out of 18 studied, are distributed in the impact structure within a radius of up to 10 km from the crater center. Second, the margins between the augite and labradorite wedges are sharp and the {110} prismatic cleavage of augite develops into fractures and thereafter into wedges. The fractures are filled with molten labradorite pushed from the neighboring bulk labradorite grain. Third, compared to the bulk labradorite, the dislocation density and the residual strain in the labradorite wedges are significantly higher. A possible mechanism of genesis of the wedges is proposed. The mechanism explains that passing of the shock waves in the basement dolerite induced (i) formation of microfractures in augite and labradorite; (ii) development of the augite prismatic cleavages into the wedges, which overprint the microfracture in the labradorite wedges; and (iii) thereafter, infilling of microfractures in the augite wedges by labradorite.
- Published
- 2016
131. Review for 'Cytoskeletal regulation of synaptogenesis in a model of human fetal brain development'
- Author
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Deepak Srivastava
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Brain development ,Human fetal ,Synaptogenesis ,Biology ,Cytoskeleton ,Neuroscience - Published
- 2019
132. Schizophrenia risk from locus-specific human endogenous retroviruses
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Claire Troakes, Deepak Srivastava, de Mulder M, Sashika Selvackadunco, Douglas F. Nixon, Greta A. Beckerle, Matthew L. Bendall, Gustavo Reyes-Terán, Christopher E. Ormsby, Keith A. Crandall, Rodrigo R.R. Duarte, and Timothy R. Powell
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Genetics ,0303 health sciences ,Human endogenous retrovirus ,viruses ,Locus (genetics) ,Biology ,Genome ,Transcriptome ,Dorsolateral prefrontal cortex ,03 medical and health sciences ,0302 clinical medicine ,medicine.anatomical_structure ,embryonic structures ,medicine ,Diagnostic biomarker ,Gene ,030217 neurology & neurosurgery ,030304 developmental biology ,Genetic association - Abstract
Schizophrenia genome-wide association studies highlight the substantial contribution of risk attributed to the non-coding genome where human endogenous retroviruses (HERVs) are encoded. These ancient viral elements have previously been overlooked in genetic and transcriptomic studies due to their poor annotation and repetitive nature. Using a new, comprehensive HERV annotation, we found that the fraction of the genome where HERVs are located (the ‘retrogenome’) is enriched for schizophrenia risk variants, and that there are 148 disparate HERVs involved in susceptibility. Analysis of RNA-sequencing data from the dorsolateral prefrontal cortex of 259 schizophrenia cases and 279 controls from the CommonMind Consortium showed that HERVs are actively expressed in the brain (n = 3,979), regulated in cis by common genetic variants (n = 1,759), and differentially expressed in patients (n = 81). Convergent analyses implicate LTR25_6q21 and ERVLE_8q24.3h as HERVs of etiological relevance to schizophrenia, which are co-regulated with genes involved in neuronal and mitochondrial function, respectively. Our findings provide a strong rationale for exploring the retrogenome and the expression of these locus-specific HERVs as novel risk factors for schizophrenia and potential diagnostic biomarkers and treatment targets.
- Published
- 2019
133. Antiviral signalling in human IPSC-derived neurons recapitulates neurodevelopmental disorder phenotypes
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Roland Nagy, Amalie Couch, Leo W. Perfect, Amanda L. Evans, Anthony C. Vernon, Declan G. Murphy, Jack Price, Grainne M. McAlonan, Katherine Warre-Cornish, Deepak Srivastava, Eva Loth, Annett Mueller, Timothy R. Powell, Matthew J. Reid, Pooja Raval, Cedric Ghevaert, and Rodrigo R.R. Duarte
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Neurite ,Biology ,medicine.disease ,Phenotype ,Cell biology ,Neurodevelopmental disorder ,Downregulation and upregulation ,Viral entry ,MHC class I ,medicine ,biology.protein ,Interferon gamma ,Progenitor cell ,medicine.drug - Abstract
Maternal immune activation increases the risk of neurodevelopmental disorders. Elevated cytokines, such as interferon-gamma (IFNγ), in offspring’s brains play a central role. IFNγ activates an antiviral cellular state, limiting viral entry and replication. In addition, IFNγ has been implicated in brain development. Here, we hypothesise that IFNγ-induced antiviral signalling contributes to molecular and cellular phenotypes associated with neurodevelopmental disorders. We find that transient IFNγ treatment of neural progenitors derived from human induced pluripotent stem cells (hIPSCs) persistently increases neurite outgrowth, phenocopying hIPSC-neurons from autistic individuals. IFNγ upregulates antiviral PML bodies and MHC class I (MHCI) genes, which persists through neuronal differentiation. Critically, IFNγ-induced neurite outgrowth requires both PML and MHCI. We also find that IFNγ disproportionately alters expression of autism and schizophrenia risk genes, suggesting convergence between these genetic and environmental risk factors. Together, these data indicate that IFNγ-induced antiviral signalling may contribute to neurodevelopmental disorder aetiology.
- Published
- 2019
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134. Early post-zygotic mutations contribute to congenital heart disease
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Joshua M. Gorham, Christine E. Seidman, Steve Depalma, Elizabeth Goldmuntz, Bruce D. Gelb, Kathryn B. Manheimer, Alexander Hsieh, Richard P. Lifton, Yufeng Shen, Jane W. Newburger, Sarah U. Morton, Wendy K. Chung, Deepak Srivastava, Emily Leann Griffin, George A. Porter, Richard W. Kim, Hongjian Qi, Daniel Bernstein, Martina Brueckner, Jon G. Seidman, Angela Tai, Martin Tristani-Firouzi, David M. McKean, and Jon A. L. Willcox
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Genetics ,Proband ,0303 health sciences ,Zygote ,Heart disease ,Somatic cell ,Biology ,medicine.disease ,3. Good health ,03 medical and health sciences ,0302 clinical medicine ,Tissue mosaicism ,medicine ,Allele ,Exome ,Gene ,030217 neurology & neurosurgery ,030304 developmental biology - Abstract
BackgroundThe contribution of somatic mosaicism, or genetic mutations arising after oocyte fertilization, to congenital heart disease (CHD) is not well understood. Further, the relationship between mosaicism in blood and cardiovascular tissue has not been determined.ResultsWe developed a computational method, Expectation-Maximization-based detection of Mosaicism (EM-mosaic), to analyze mosaicism in exome sequences of 2530 CHD proband-parent trios. EM-mosaic detected 326 mosaic mutations in blood and/or cardiac tissue DNA. Of the 309 detected in blood DNA, 85/97 (88%) tested were independently confirmed, while 7/17 (41%) candidates of 17 detected in cardiac tissue were confirmed. MosaicHunter detected an additional 64 mosaics, of which 23/46 (50%) among 58 candidates from blood and 4/6 (67%) of 6 candidates from cardiac tissue confirmed. Twenty-five mosaic variants altered CHD-risk genes, affecting 1% of our cohort. Of these 25, 22/22 candidates tested were confirmed. Variants predicted as damaging had higher variant allele fraction than benign variants, suggesting a role in CHD. The frequency of mosaic variants above 10% mosaicism was 0.13/person in blood and 0.14/person in cardiac tissue. Analysis of 66 individuals with matched cardiac tissue available revealed both tissue-specific and shared mosaicism, with shared mosaics generally having higher allele fraction.ConclusionsWe estimate that ~1% of CHD probands have a mosaic variant detectable in blood that could contribute to cardiac malformations, particularly those damaging variants expressed at higher allele fraction compared to benign variants. Although blood is a readily-available DNA source, cardiac tissues analyzed contributed ~5% of somatic mosaic variants identified, indicating the value of tissue mosaicism analyses.
- Published
- 2019
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135. Abstract 197: Transcription Factor Interactome in Human iPS-derived Cardiac Progenitors is Enriched for Proteins Associated With Congenital Heart Disease
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Bonnie Cole, Michael McGregor, Desmond Richmond-Buccola, Nevan J. Krogan, Barbara Gonzalez Teran, Deepak Srivastava, Kaitlen Samse, Katherine S. Pollard, Maureen Pittman, and Ruth Huttenhain
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Cardiac progenitors ,Heart disease ,Physiology ,medicine ,Genomics ,Biology ,Cardiology and Cardiovascular Medicine ,medicine.disease ,Bioinformatics ,Proteomics ,Interactome ,Gene ,Transcription factor - Abstract
Congenital heart disease (CHD) affects ~1% of live births and remains the leading cause of mortality in infants. While large-scale genetic studies have uncovered genes associated with CHD, distinguishing variants that confer risk from the background noise of inconsequential variants remains a challenge. Causative mutations in transcription factors (TF) essential for cardiovascular development, such as NKX2-5, GATA4 and TBX5, have been identified in familial cases of CHD, however they are rare. To expand our understanding of their molecular function and to test whether their interacting proteins may be enriched for variants associated with CHD. We defined the protein-protein interaction (PPI) network of NKX2-5, GATA4 and TBX5 using unbiased mass spectrometry in human iPSC-derived cardiac progenitors (iPS-CPs). This approach yielded a network of 172 proteins. An interdependent gene-regulatory role has been reported at the DNA-binding level for these 3 TF during cardiac development, and we also found interdependent protein interactomes where loss of one TF affected the interactome of the others. Interactomes for each were enriched in proteins involved in similar biological processes, such as chromatin remodeling and gene regulation, or previously unrelated processes such as splicing and mRNA transport. Integration of the iPS-CP-PPI network with the CHD-associated damaging variants found in the Pediatric Cardiac Genomics Consortium whole-exome sequencing cohort revealed statistically significant enrichment in the GATA4 interactome for de novo missense variants. In contrast, neither the TBX5 or NKX2-5 PPIs were enriched for either de novo missense or rare damaging variants. Finally, we developed a framework to rank PPIs with reported damaging variants for functional validation studies. Overall, this work identified novel protein interactors of TFs essential for cardiac development, offering new insights regarding their regulatory roles and the mechanisms through which they may cause CHD.
- Published
- 2019
136. Loss of EPAC2 alters dendritic spine morphology and inhibitory synapse density
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Michiko Sumiya, Kelly A. Jones, Deepak Srivastava, Peter Penzes, and Kevin M. Woolfrey
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Male ,0301 basic medicine ,Dendritic spine ,EPAC2 ,Vesicular Inhibitory Amino Acid Transport Proteins ,Dendritic Spines ,Vesicular glutamate transporter 1 ,AMPA receptor ,Inhibitory postsynaptic potential ,Gyrus Cinguli ,Article ,Dendritic spines ,Synaptic plasticity ,Mice ,03 medical and health sciences ,Cellular and Molecular Neuroscience ,0302 clinical medicine ,Dendritic arborization ,Animals ,Guanine Nucleotide Exchange Factors ,Small GTPase ,Receptors, AMPA ,Molecular Biology ,Cells, Cultured ,biology ,Excitatory Postsynaptic Potentials ,Cell Biology ,Autism spectrum disorders ,Cadherins ,Cell biology ,Mice, Inbred C57BL ,030104 developmental biology ,Inhibitory Postsynaptic Potentials ,Synapses ,Excitatory postsynaptic potential ,biology.protein ,Guanine nucleotide exchange factor ,030217 neurology & neurosurgery ,Excitatory and inhibitory balance - Abstract
EPAC2 is a guanine nucleotide exchange factor that regulates GTPase activity of the small GTPase Rap and Ras and is highly enriched at synapses. Activation of EPAC2 has been shown to induce dendritic spine shrinkage and increase spine motility, effects that are necessary for synaptic plasticity. These morphological effects are dysregulated by rare mutations of Epac2 associated with autism spectrum disorders. In addition, EPAC2 destabilizes synapses through the removal of synaptic GluA2/3-containing AMPA receptors. Previous work has shown that Epac2 knockout mice (Epac2−/−) display abnormal social interactions, as well as gross disorganization of the frontal cortex and abnormal spine motility in vivo. In this study we sought to further understand the cellular consequences of knocking out Epac2 on the development of neuronal and synaptic structure and organization of cortical neurons. Using primary cortical neurons generated from Epac2+/+ or Epac2−/− mice, we confirm that EPAC2 is required for cAMP-dependent spine shrinkage. Neurons from Epac2−/− mice also displayed increased synaptic expression of GluA2/3-containing AMPA receptors, as well as of the adhesion protein N-cadherin. Intriguingly, analysis of excitatory and inhibitory synaptic proteins revealed that loss of EPAC2 resulted in altered expression of vesicular GABA transporter (VGAT) but not vesicular glutamate transporter 1 (VGluT1), indicating an altered ratio of excitatory and inhibitory synapses onto neurons. Finally, examination of cortical neurons located within the anterior cingulate cortex further revealed subtle deficits in the establishment of dendritic arborization in vivo. These data provide evidence that loss of EPAC2 enhances the stability of excitatory synapses and increases the number of inhibitory inputs., Highlights • EPAC2 is required for cAMP-dependent spine remodeling. • Loss of EPAC2 results in over-stabilized excitatory synapses. • Loss of EPAC2 results in an increase in inhibitory input onto neurons. • EPAC2 is required for correct dendritic arborization and spine formation in vivo.
- Published
- 2019
137. Context-Specific Transcription Factor Functions Regulate Epigenomic and Transcriptional Dynamics during Cardiac Reprogramming
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Reuben Thomas, Karishma Pratt, Kaitlen Samse-Knapp, Lin Ye, Ethan Radzinsky, Joke G. van Bemmel, Nicole Stone, Kathryn N. Ivey, Casey A. Gifford, Amelia Schricker, Tamer M.A. Mohamed, Pengzhi Yu, Deepak Srivastava, and Katherine S. Pollard
- Subjects
ATAC-seq ,cardiomyocyte ,Cardiovascular ,Medical and Health Sciences ,Epigenesis, Genetic ,Machine Learning ,Mice ,0302 clinical medicine ,MEF2C ,Myocytes, Cardiac ,Cells, Cultured ,transcription factor ,Epigenomics ,Regulation of gene expression ,0303 health sciences ,Cultured ,single-cell RNA-seq ,MEF2 Transcription Factors ,Cell Differentiation ,Biological Sciences ,Cellular Reprogramming ,Cell biology ,ChIP-seq ,Heart Disease ,Molecular Medicine ,Reprogramming ,Cardiac ,Protein Binding ,Biotechnology ,Transcriptional Activation ,Cells ,Biology ,Chromatin remodeling ,Article ,03 medical and health sciences ,Genetic ,Genetics ,Animals ,Cell Lineage ,Transcription factor ,030304 developmental biology ,Myocytes ,Human Genome ,cardiac fibroblast ,reprogramming ,Cell Biology ,Chromatin Assembly and Disassembly ,GATA4 Transcription Factor ,Ectopic expression ,T-Box Domain Proteins ,030217 neurology & neurosurgery ,Epigenesis ,Developmental Biology - Abstract
Ectopic expression of combinations of transcription factors (TFs) can drive direct lineage conversion, thereby reprogramming a somatic cell's identity. To determine the molecular mechanisms by which Gata4, Mef2c, and Tbx5 (GMT) induce conversion from a cardiac fibroblast toward an induced cardiomyocyte, we performed comprehensive transcriptomic, DNA-occupancy, and epigenomic interrogation throughout the reprogramming process. Integration of these datasets identified new TFs involved in cardiac reprogramming and revealed context-specific roles for GMT, including the ability of Mef2c and Tbx5 to independently promote chromatin remodeling at previously inaccessible sites. We also find evidence for cooperative facilitation and refinement of each TF's binding profile in a combinatorial setting. A reporter assay employing newly defined regulatory elements confirmed that binding of a single TF can be sufficient for gene activation, suggesting that co-binding events do not necessarily reflect synergy. These results shed light on fundamental mechanisms by which combinations of TFs direct lineage conversion.
- Published
- 2019
138. Brain-synthesized estrogens regulate cortical migration in a sexually divergent manner
- Author
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Atsushi Saito, Katherine J. Sellers, Matthew C.S. Denley, Deepak Srivastava, and Atsushi Kamiya
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Fetus ,medicine.medical_specialty ,Gene knockdown ,biology ,Subventricular zone ,Corticogenesis ,Basal (phylogenetics) ,medicine.anatomical_structure ,Endocrinology ,Cerebral cortex ,Internal medicine ,Cortex (anatomy) ,medicine ,biology.protein ,Aromatase ,10. No inequality - Abstract
Estrogens play an important role in the sexual dimorphisms that occur during brain development, including the neural circuitry that underlies sex-typical and socio-aggressive behaviors. Aromatase, the enzyme responsible for the conversion of androgens to estrogens, is expressed at high levels during early development in both male and female cortices, suggesting a role for brain-synthesized estrogens during corticogenesis. This study investigated how the local synthesis of estrogens affects neurodevelopment of the cerebral cortex, and how this differs in males and females by knockdown expression of the Cyp19a1 gene, which encodes aromatase, between embryonic day 14.5 and postnatal day 0 (P0). The effects of Cyp19a1 knockdown on neural migration was then assessed. Aromatase was expressed in the developing cortex of both sexes, but at significantly higher levels in male than female mice. Under basal conditions, no obvious differences in cortical migration between male and female mice were observed. However, knockdown of Cyp19a1 increased the number GFP-positive cells in the cortical plate, with a concurrent decrease in the subventricular zone/ventricular zone in P0 male mice. The opposite effect was observed in females, with a significantly reduced number of GFP-positive cells migrating to the cortical plate. These findings have important implications for our understanding of the role of fetal steroids for neuronal migration during cerebral cortex development. Moreover, these data indicate that brain-synthesized estrogens regulate radial migration through distinct mechanisms in males and females.
- Published
- 2019
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139. Brain-synthesized oestrogens regulate cortical migration in a sexually divergent manner
- Author
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Evangeline M. Foster, Deepak Srivastava, Katherine J. Sellers, Matthew C.S. Denley, Irene Salgarella, Atsushi Saito, Alessio Delogu, and Atsushi Kamiya
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Male ,medicine.medical_specialty ,Subventricular zone ,03 medical and health sciences ,Mice ,0302 clinical medicine ,Internal medicine ,Cortex (anatomy) ,Lateral Ventricles ,medicine ,Animals ,Aromatase ,030304 developmental biology ,Progenitor ,Neurons ,0303 health sciences ,Gene knockdown ,biology ,Estradiol ,General Neuroscience ,Brain ,Estrogens ,Neural stem cell ,Corticogenesis ,medicine.anatomical_structure ,Endocrinology ,biology.protein ,Female ,Neural development ,030217 neurology & neurosurgery - Abstract
Oestrogens play an important role in brain development where they have been implicated in controlling various cellular processes. Several lines of evidence have been presented showing that oestrogens can be synthesized locally within the brain. Studies have demonstrated that aromatase, the enzyme responsible for the conversion of androgens to oestrogens, is expressed during early development in both male and female cortices. Furthermore, 17β-oestradiol has been measured in foetal brain tissue from multiple species. 17β-oestradiol regulates neural progenitor proliferation as well as the development of early neuronal morphology. However, what role locally derived oestrogens play in regulating cortical migration and, moreover, whether these effects are the same in males and females are unknown. Here, we investigated the impact of knockdown expression of Cyp19a1, which encodes aromatase, between embryonic day (E) 14.5 and postnatal day 0 (P0) had on neural migration within the cortex. Aromatase was expressed in the developing cortex of both sexes, but at significantly higher levels in male than female mice. Under basal conditions, no obvious differences in cortical migration between male and female mice were observed. However, knockdown of Cyp19a1 resulted in an increase in cells within the cortical plate, and a concurrent decrease in the subventricular zone/ventricular zone in P0 male mice. Interestingly, the opposite effect was observed in females, who displayed a significant reduction in cells migrating to the cortical plate. Together, these findings indicate that brain-derived oestrogens regulate radial migration through distinct mechanisms in males and females.
- Published
- 2019
140. Author response for 'Exchange protein directly activated by <scp>cAMP</scp> 2 is required for corticotropin‐releasing hormone‐mediated spine loss'
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Deepak Srivastava, Peter Penzes, and Zhong Xie
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medicine.medical_specialty ,Corticotropin-releasing hormone ,Endocrinology ,business.industry ,Internal medicine ,medicine ,business ,SPINE (molecular biology) - Published
- 2019
141. EPAC2 is required for corticotropin-releasing hormone-mediated spine loss
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Deepak Srivastava, Zhong Xie, and Peter Penzes
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endocrine system ,0303 health sciences ,Dendritic spine ,RAPGEF4 ,Hippocampus ,Biology ,Cortex (botany) ,Cell biology ,03 medical and health sciences ,Corticotropin-releasing hormone ,0302 clinical medicine ,Excitatory synapse ,nervous system ,Small GTPase ,Guanine nucleotide exchange factor ,030217 neurology & neurosurgery ,030304 developmental biology - Abstract
Corticotropin-releasing hormone (CRH) is produced in response to stress. This hormone plays a key role in mediating neuroendocrine, behavioral, and autonomic responses to stress. The CRH receptor 1 (CRHR1) is expressed in multiple brain regions including the cortex and hippocampus. Previous studies have shown that activation of CRHR1 by CRH results in the rapid loss of dendritic spines. Exchange protein directly activated by cAMP (EPAC2, also known as RapGEF4), a guanine nucleotide exchange factor (GEF) for the small GTPase Rap, has been linked with CRHR1 signaling. EPAC2 plays a critical role in regulating dendritic spine morphology and number in response to several extracellular signals. But whether EPAC2 links CRHR1 with dendritic spine remodeling is unknown. Here we show that CRHR1 is highly enriched in the dendritic spines of primary cortical neurons. Furthermore, we find that EPAC2 and CRHR1 co-localize in cortical neurons. Critically, short hairpin RNA-mediated knockdown of Epac2 abolished CRH-mediated spine loss in primary cortical neurons. Taken together, our data indicate that EPAC2 is required for the rapid loss of dendritic spines induced by CRH. These findings identify a novel pathway by which acute exposure to CRH may regulate synaptic structure and ultimately responses to acute stress.
- Published
- 2019
142. Filtration Based Noise Reduction Technique in an Image
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Deepak Srivastava, Dheresh Soni, and Vibhor Sharma
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Computer science ,business.industry ,Noise reduction ,Detector ,ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION ,Process (computing) ,020207 software engineering ,Salt-and-pepper noise ,02 engineering and technology ,Filter (signal processing) ,Image (mathematics) ,law.invention ,Noise ,Transmission (telecommunications) ,law ,0202 electrical engineering, electronic engineering, information engineering ,020201 artificial intelligence & image processing ,Computer vision ,Artificial intelligence ,business ,Filtration ,Degradation (telecommunications) - Abstract
Image transmission is a process that is performed in all kind of multimedia systems such as space crafts and cellular phones. When an image is inputted for broadcasting, it doesn't contain that much of quality after transmission as original image was having. Noise is the main factor that can contaminate the final image in distinct ways like transmission through air or decompression noise after compressed data that is stored. The final image can be degraded because of this. To resolve the issue of degradation, different filtering steps can be applied or preprocessing can be done. Lots of noise suppression filters have been designed to reduce the degradation in the appeared image after transmission. Different filtration techniques are used to overcome this problem. But image may be blurred after filtration. Median filtration yields best results is such a way that image won't be blurred after transmission. In this paper, we present a filtration technique to decrease noise in a transformed image with the help of cellular automata concept. Our model of CA works for reducing two kind noises in resultant image. First is salt and pepper noise and second is gaussain noise. Our proposed model reduces these noises effectively as compared to other models.
- Published
- 2019
143. Optimization of CSMA (Carrier Sense Multiple Access) over AODV, DSR & WRP Routing Protocol
- Author
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Deepak Srivastava, Vibhor Sharma, and Dheresh Soni
- Subjects
Routing protocol ,Mobility model ,business.industry ,Wireless network ,Computer science ,Network packet ,Wireless ad hoc network ,ComputerSystemsOrganization_COMPUTER-COMMUNICATIONNETWORKS ,010401 analytical chemistry ,GloMoSim ,Wireless Routing Protocol ,020206 networking & telecommunications ,02 engineering and technology ,Mobile ad hoc network ,Network topology ,01 natural sciences ,0104 chemical sciences ,Ad hoc On-Demand Distance Vector Routing ,0202 electrical engineering, electronic engineering, information engineering ,business ,Computer network - Abstract
Mobile adhoc network (MANET) is a infrastructure less wireless network which do not have central control, and where each mobile node behave as either sender or receiver. The MANETs[1] are dynamic networks because the network topology keeps on changing because of the mobility of the nodes. There are multiple protocols that have been designed to route the packet in these types of networks. There are certain mobility model is designed with some other network parameter. To get the effective routing in a given network, we need to choose right protocol. The GloMoSim is used as the simulate network parameter and three MANET protocols namely wireless routing protocol (AODV[1],[2], DSR[1],[2], WRP[1],[2]) with MAC layer protocol is evaluated. Our results demonstrated the usefulness of WRP model, it gives better result, AS AODV is out performed. On the basis of result, We show that WRP is a better protocol for MANETs compared to AODV and DSR. The same simulation platform could be used to test other protocols.
- Published
- 2019
144. Optimization of security issues in adoption of cloud ecosystem
- Author
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Deepak Srivastava, Vibhor Sharma, and Dheresh Soni
- Subjects
ComputingMilieux_GENERAL ,Cloud computing security ,business.industry ,Computer science ,Data_MISCELLANEOUS ,Cloud computing ,Ecosystem ,Cloud service provider ,business ,Computer security ,computer.software_genre ,computer - Abstract
This paper presents a concise preface for the Cloud ecosystem, logical cloud security challenges and Confidence Mechanism concept, (REO) architecture and opportunities are presented briefly. To noticeably and resourcefully discuss security intimidation, risks, controls, agreement and other safety desires within the cloud framework, this paper also discuss cloud service providers, cloud vendors and cloud tenants with a framework. Role of security in cloud service ecosystem is further elaborate in the paper.
- Published
- 2019
145. The epigenetics of autism
- Author
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Dwaipayan Adhya, Varun Warrier, Mark R. N. Kotter, Arkoprovo Paul, Aicha Massrali, Simon Baron-Cohen, and Deepak Srivastava
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Histone ,Brain development ,biology ,DNA methylation ,biology.protein ,medicine ,Autism ,Epigenetics of autism ,Epigenetics ,medicine.disease ,Neuroscience ,Genetic association - Abstract
Autism spectrum conditions (ASCs) are neurodevelopmental in origin and entail social-communication disability alongside unusually narrow interests and difficulties adjusting to unexpected change. The cause of ASCs is complex due to the interplay of an array of genetic and environmental factors. Although ASCs are known to be highly heritable, genetic sequencing and association studies have identified only a fraction of the total number of genes thought to be associated with the condition. Nevertheless, neither genetic components nor environmental factors have been able to elucidate the pathophysiology of nonsyndromic ASCs. Recently there has been a paradigm shift in autism research toward investigating how environment mediates gene expression subsequently affecting biological pathways crucial for brain development. In this chapter, we discuss the key epigenetic mechanisms, such as DNA methylation and histone modifications, as potential contributors to the etiopathogenesis of ASCs. We also highlight some of the risk factors affecting autism epigenetics, the limitations of current research, and the implications for future work.
- Published
- 2019
146. Screening and biochemical analysis of GATA4 sequence variations identified in patients with congenital heart disease
- Author
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Schluterman, Marie K., Krysiak, Amanda E., Kathiriya, Irfan S., Abate, Nicola, Chandalia, Manisha, Deepak, Srivastava, and Garg, Vidu
- Published
- 2007
- Full Text
- View/download PDF
147. Psychiatric risk geneNT5C2regulates protein translation in human neural progenitor cells
- Author
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Sang Hyuck Lee, Robin M. Murray, Marie-Caroline Cotel, Ioannis Eleftherianos, Nicholas John Bray, Rodrigo R.R. Duarte, Deepak Srivastava, Gerome Breen, Nathaniel D. Bachtel, Gary A. Hovsepian, Douglas F. Nixon, Claire Troakes, Anthony C. Vernon, Timothy R. Powell, Iain A. Watson, and Sashika Selvackadunco
- Subjects
0303 health sciences ,03 medical and health sciences ,0302 clinical medicine ,Ampk signaling ,Risk gene ,Biology ,Protein translation ,030217 neurology & neurosurgery ,Neural stem cell ,030304 developmental biology ,Cell biology - Abstract
Genome-wide significant variants associated with combined risk for major psychiatric disorders on chromosome 10q24 affect the expression of the cytosolic 5’-nucleotidase II (NT5C2, cN-II) in population controls, implicating it as a psychiatric susceptibility gene. Risk alleles are associated with reduced expression of this gene in the developing and adult brain, but the resulting neurobiological risk mechanisms remain elusive. In this study, we provide further evidence for the association ofNT5C2with psychiatric disorders, and use a functional genetics approach to gain a deeper understanding of the function of this risk gene in the nervous system.NT5C2expression was significantly reduced in thepost-mortembrain of schizophrenia and bipolar disorder patients, and its protein predominately expressed in neurons within the adult brain. Using human neural progenitor cells (hNPCs), we found thatNT5C2expression peaked at the neural progenitor state, where the encoded protein was ubiquitously distributed through the cell.NT5C2knockdown in hNPCs elicited transcriptomic changes associated with protein translation, that were accompanied by regulation of adenosine monophosphate-activated protein kinase (AMPK) signalling and ribosomal protein S6 (rpS6) activity. To identify the effect of reduced neuronalNT5C2expression at a systems level, we knockdown its homologue,CG32549, inDrosophila melanogasterCNS. This elicited impaired climbing behaviour in the model organism. Collectively, our data implicateNT5C2expression in risk for psychiatric disorders and inDrosophila melanogastermotility, and further suggest that risk is mediated via regulation of AMPK signalling and protein translation during early neurodevelopment.
- Published
- 2018
148. Conserved Epigenetic Regulatory Logic Infers Genes Governing Cell Identity
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Naihe Jing, Yash Chhabra, Mikael Bodén, Quan Nguyen, Yuliangzi Sun, Patrick P.L. Tam, Gaia Andreoletti, Woo Jun Shim, Lionel Christiaen, Brad Balderson, Michael Alexanian, Yuliang Wang, Sophie Shen, Deepak Srivastava, Guangdun Peng, Aaron G. Smith, Enakshi Sinniah, Nathan J. Palpant, Burcu Vitrinel, Jun Xu, and Michael Piper
- Subjects
Epigenomics ,Cell type ,Histology ,Cellular differentiation ,Cell ,Cell type specific ,Morphogenesis ,Computational biology ,Biology ,Article ,Pathology and Forensic Medicine ,Transcriptome ,03 medical and health sciences ,0302 clinical medicine ,Genome editing ,medicine ,Humans ,CRISPR ,Epigenetics ,Induced pluripotent stem cell ,Gene ,Organ system ,Regulator gene ,030304 developmental biology ,0303 health sciences ,Cell Differentiation ,Cell Biology ,Cell identity ,medicine.anatomical_structure ,030217 neurology & neurosurgery - Abstract
SUMMARY Determining genes that orchestrate cell differentiation in development and disease remains a fundamental goal of cell biology. This study establishes a genome-wide metric based on the gene-repressive trimethylation of histone H3 at lysine 27 (H3K27me3) across hundreds of diverse cell types to identify genetic regulators of cell differentiation. We introduce a computational method, TRIAGE, which uses discordance between gene-repressive tendency and expression to identify genetic drivers of cell identity. We apply TRIAGE to millions of genome-wide single-cell transcriptomes, diverse omics platforms, and eukaryotic cells and tissue types. Using a wide range of data, we validate the performance of TRIAGE in identifying cell-type-specific regulatory factors across diverse species including human, mouse, boar, bird, fish, and tunicate. Using CRISPR gene editing, we use TRIAGE to experimentally validate RNF220 as a regulator of Ciona cardiopharyngeal development and SIX3 as required for differentiation of endoderm in human pluripotent stem cells. A record of this paper’s transparent peer review process is included in the Supplemental Information., In Brief Perturbing genes controlling cell decisions have major implications in development or disease. However, identifying key regulatory genes from the thousands expressed in a cell is challenging. TRIAGE is a computational method that distills patterns of epigenetic repression across diverse cell types to infer regulatory genes using input gene expression data from any cell type. Demonstrating its utility, we combine single-cell RNA-seq and TRIAGE to identify and experimentally confirm novel regulators of heart development in evolutionarily distant species., Graphical Abstract
- Published
- 2020
149. Electronic devices, structures and transport in carbon based materials: molecular electronics and quantum computing.
- Author
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Deepak Srivastava
- Published
- 2001
- Full Text
- View/download PDF
150. Sarcomeres and Cardiac Growth: Tension in the Relationship
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Deepak Srivastava and Saptarsi M. Haldar
- Subjects
0301 basic medicine ,03 medical and health sciences ,Myofilament ,030104 developmental biology ,Tension (physics) ,Mutant ,Molecular Medicine ,Anatomy ,Biology ,Contractile apparatus ,Molecular Biology ,Sarcomere ,Cell biology - Abstract
Genetic mutations in the cardiomyocyte contractile apparatus cause aberrant cardiac growth categorized morphologically as hypertrophic or dilated. A recent study leverages an array of mutant mouse models to extrapolate a new integrated parameter: the myofilament ‘tension index', which predicts patterns of cardiac growth resulting from individual sarcomeric mutations. These findings may inform genotype-specific therapies.
- Published
- 2016
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