Browsing by Author "Richa Singh"

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A reduced graphene oxide ceramic electrode modified with one MoNomer doubly imprinted acryloylated tetraamine cobalt phthalocyanine polymer for the simultaneous analysis of anticancerous drugs
(Elsevier B.V., 2019) Sana Fatma; Bhim Bali Prasad; Kislay Singh; Richa Singh; Swadha Jaiswal
The present work illustrates a novel technique for the development of One MoNomer dual imprinted polymer, utilizing acryloylated tetraamine cobalt phthalocyanine as a tetrafunctional monomer, on the surface of a reduced graphene oxide ceramic electrode. This electrode was used for the simultaneous analysis of a mixture of anticancerous drugs, chlorambucil and dacarbazine, at ultra-trace level in real samples. The acryloylated tetraamine cobalt phthalocyanine was typically selected in this work for polymerization because it served both as a monomer and a crosslinker, with higher electroconductivity. The detection sensitivity of the measurement was realized to be 0.041 ng mL−1 and 0.017 ng mL−1 for chlorambucil and dacarbazine, respectively in the aqueous environment. The complex matrices of blood plasma, urine and pharmaceutics were examined which yielded the validated results without any effects of matrix complications including cross-reactivity, and false-positives. The therapeutic ranges of the test analyte(s) (chlorambucil 0.159–28.524 ng mL−1, dacarbazine 0.063–37.286 ng mL−1) were realized to be larger demonstrating perfect linearity (R2 = 0.99) with the improved voltammetric response. This work merits special significance to decide the adequate supplementation of drug(s) in combined therapy for cancer treatment. © 2018 Elsevier B.V.
Anti-Parkinsonian effect of Mucuna pruriens and Ursolic acid on GSK3β/Calcium signaling in neuroprotection against Rotenone-induced Parkinsonism
(Elsevier B.V., 2022) Walia Zahra; Hareram Birla; Saumitra Sen Singh; Aaina Singh Rathore; Hagera Dilnashin; Richa Singh; Priyanka Kumari Keshri; Shekhar Singh; Surya Pratap Singh
Background: Exposure of environmental toxin is linked to the onset of Parkinson's disease (PD), especially in majority of sporadic cases. One of such toxins, namely Rotenone has been widely investigated to produce the Parkinsonian model in laboratories. The toxin causes the death of the dopaminergic neurons, aggregation of α-Synuclein, oxidative stress, neuroinflammation and initiate other pathways leading to PD pathogenesis. Glycogen synthase kinase-3 (GSK-3) is a pleiotropic serine/threonine protein kinase found in eukaryotes. One of the two isoforms of the enzyme; GSK-3β plays an important role in regulating the pathogenesis of neurodegenerative diseases, including PD. Whereas, Calcium (Ca2+) is found to regulate important cellular activities in all eukaryotic cells. However, an increased Ca2+ concentration is seen during ageing and the progression of neurodegenerative diseases. Thus, maintaining the Ca2+ homoeostasis is very crucial for proper cell function. Methodology: Hence, behavioural tests were performed to assess the motor abnormalities; immunohistochemical and western blot analyses to identify the alteration in the protein expression; and mitochondrial complexes and antioxidants assay to detect the extent of mitochondrial dysfunction in Rotenone-induced Parkinsonian mouse model. Alternatively, the effect of Mucuna pruriens (Mp) and Ursolic acid (UA) in the PD mouse model was also observed. Results: Increased Ca2+level, and activation of GSK-3β was observed in the Rotenone-intoxicated mouse model of PD. The extract of Mp and UA, on the other hand shows neuroprotection through their anti-oxidative and anti-inflammatory properties. However, their role in maintaining the Ca2+ level and GSK-3β signaling is not yet observed in PD. So, our study deals with the downregulated activity of GSK-3β and Ca2+ level upon the administration of Mp extract and UA, thereby providing neuroprotection to the PD mouse model. Conclusion: Thus, this study deals to explore further the neuroprotective activity of Mp and UA through GSK-3β/Calcium signaling by ameliorating mitochondrial dysfunction mediated apoptosis and inhibiting the overexpression of α-Synuclein in Rotenone-induced PD mouse model. © 2022
Assessment of rainfall variability in Ladakh amidst evolving climate
(Springer Science and Business Media B.V., 2024) Richa Singh; R. Bhatla
Ladakh is characterized by a cold desert and fragile ecosystem that is geographically connected to the Western Himalaya and highly susceptible to changing climate. In the current scenario, the region is receiving more extreme rain events, which have disturbed ecosystem balance and triggered disasters like flash floods and landslides. Therefore, a comprehensive study of rainfall patterns over the past 90 years has been done here, which provides insight into climate trends. In this study, the rainfall pattern has been statistically quantified on a tricadal (30-year period) and decadal (10-year period) basis from 1932 to 2021 by using gridded rainfall data from the India Meteorological Department (IMD) to analyze changes in rainfall in all four seasons, namely pre-monsoon, monsoon, post-monsoon, and winter, and calculate the trends by using non-parametric tests like Mann–Kendall (MK) and Sen’s slope. The results indicate that certain seasons have seen higher rainfall than others. This study employs the precipitation concentration index (PCI) for rainfall variation estimation, accounting for overlapping time segments. PCI values show uniform and highly concentrated rainfall, which indicates the potential for extreme weather events. The study indicates a decadal shift possibly linked with broader climate cycles along with an increased frequency of extreme rain events. Long-term trends are visible in the tricadal analysis, with increased pre-monsoon rainfall in T1 (1932–1961) and decreased monsoon and post-monsoon rainfall in T2 (1962–1991) and T3 (1992–2021). This study is useful in water resources management, agriculture, and ecosystem services. © The Author(s), under exclusive licence to Springer Nature B.V. 2024..
Biomimetic Polymer-Based Electrochemical Sensor Using Methyl Blue-Adsorbed Reduced Graphene Oxide and Functionalized Multiwalled Carbon Nanotubes for Trace Sensing of Cyanocobalamin
(American Chemical Society, 2018) Richa Singh; Swadha Jaiswal; Kislay Singh; Sana Fatma; Bhim Bali Prasad
The paper reports a three-dimensional cyanocobalamin (Cbl)-selective biomimetic imprinted polymer. For this, a methyl blue-adsorbed reduced graphene oxide (rGO) and functionalized multiwalled carbon nanotubes (f-MWCNTs) composite, duly functionalized with acryloylurea, was used. This exhibited higher electroconductivity and larger surface area in comparison to either pristine carbon nanotubes or graphene. It is the first synthetic biomimetic polymer of Cbl, grown on the surface of a pencil graphite electrode. In this work, the adsorption of methyl blue over the rGO sheets improved its solubility, conductivity, and self-assembly properties. Such assemblies of rGO sheets and f-MWCNTs provide enhanced kinetics and conductivity to the entire architectural design of a molecularly imprinted polymer. The ultratrace detection of Cbl was feasible by differential-pulse voltammetric transduction. This sensor exhibited high sensibility and selectivity for Cbl detection, especially in real samples. © 2018 American Chemical Society.
Climate Change, Disaster and Adaptations: Human Responses to Ecological Changes
(Springer, 2022) Richa Singh; Kirpa Ram; Chandrashekhar Yadav; Azizur Rahman Siddiqui
The impact of climate change is recorded in sea level rise, ocean acidification, coral bleaching, glacier reduction on a shorter time scale as well as an increase of earth’s surface temperature (i.e. global warming) in geological landforms, in ocean sediments and ice cores globally on a longer time scales. Although both natural processes such as change in solar radiation and sunspot activities are most likely to cause climate change, anthropogenic emissions are linked with the recent climate change such as cloud burst and abrupt change in rainfall pattern etc. In the current scenario, the ecosystem is degrading at a faster rate which has led to extreme events like flood, forest fires and drought. In addition, climate change is also linked with other problems such as epidemic, vegetation and habitat losses, some of these can result in a disaster. These disasters can significantly impair the economic growth of the county. Among the entire mammals, only humans have colonised all over the earth. They adapt in such a way that they can survive in extreme climates of geographical poles, arid desert, high altitudes of mountains and remote islands of the Pacific. Most of the time, humans such as sea nomads adapt to the changes occurring in their environment by changing their genetic adaptation to climate change. However, humans sometimes can’t adapt to the changing environment, and they migrate to a suitable place. The observed genetic makeup in modern Indo-Aryans also supports the above hypothesis that climate change caused human migration during and after the collapse of the Indus Valley Civilisation. The literature clearly shows that the main reasons behind the migration are natural disaster, lack of natural resources and poor economic condition. © The Author(s), under exclusive license to Springer Nature Switzerland AG 2022.
Combination of Drug Delivery through Nanocarriers for Brain Diseases
(CRC Press, 2024) Hagera Dilnashin; Shekhar Singh; Richa Singh; Surya Pratap Singh
Present-day treatment therapies for brain diseases mostly provide only symptomatic treatments and there is a fear they may become obsolete in no time due to their poor pharmacokinetic properties. The natural barriers of the brain hinder the delivery of therapeutic drugs to brain cells. The most important of these barriers is the blood-brain barrier. Thus, for the treatment of chronic brain disorders, novel drug-delivery vehicles are being used for controlled and target-specific delivery of therapeutic compounds. The most successful drug-delivery systems are nanocarriers. They increase the selectivity of targeted therapy to specific organs, tissues, and even at the cellular level, thus diminishing exposure to healthy tissues. Moreover, a lower amount of drugs is used for nanoparticle delivery. Advanced techniques using multiple drugs for co-delivery in a single nano-based system demonstrate better therapeutic results than monotherapy. Nanomedicines address the lacunae of conventional therapy, which is evident through various clinical and preclinical studies showing significantly improved targeted drug delivery and lower side effects. The current chapter presents a comprehensive update on the importance of several nanocarrier-based combinational drug-delivery techniques for the treatment of several chronic brain disorders. In addition, the chapter also enlightens on the challenges of preparing and delivering nano-therapies and provides suggestions to outpace them. This chapter not only provides insights into the wonder of nano-based drug-delivery approaches but also into the combination drug delivery through nanocarrier delivery as potential treatment therapies for neurological disorders. © 2024 selection and editorial matter, Anurag Kumar Singh, Vivek K. Chaturvedi, and Jay Singh; individual chapters, the contributors.
Comparison of neural networks techniques to predict subsurface parameters based on seismic inversion: a machine learning approach
(Springer Science and Business Media Deutschland GmbH, 2024) Nitin Verma; S.P. Maurya; Ravi kant; K.H. Singh; Raghav Singh; A.P. Singh; G. Hema; M.K. Srivastava; Alok K. Tiwari; P.K. Kushwaha; Richa Singh
Seismic inversion, complemented by machine learning algorithms, significantly improves the accuracy and efficiency of subsurface parameter estimation from seismic data. In this comprehensive study, a comparative analysis of machine learning techniques is conducted to predict subsurface parameters within the inter-well region. The objective involves employing three separate machine learning algorithms namely Probabilistic Neural Network (PNN), multilayer feedforward neural network (MLFNN), and Radial Basis Function Neural Network (RBFNN). The study commences by generating synthetic data, which is then subjected to machine learning techniques for inversion into subsurface parameters. The results unveil exceptionally detailed subsurface information across various methods. Subsequently, these algorithms are applied to real data from the Blackfoot field in Canada to predict porosity, density, and P-wave velocity within the inter-well region. The inverted results exhibit a remarkable alignment with well-log parameters, achieving an average correlation of 0.75, 0.77, and 0.86 for MLFNN, RBFNN, and PNN algorithms, respectively. The inverted volumes portray a consistent pattern of impedance variations spanning 7000–18000 m/s*g/cc, porosity ranging from 5 to 20%, and density within the range of 1.9–2.9 g/cc across the region. Importantly, all these methods yield mutually corroborative results, with PNN displaying a slight edge in estimation precision. Additionally, the interpretation of the inverted findings highlights anomalous zones characterized by low impedance, low density, and high porosity, seamlessly aligning with well-log data and being identified as sand channel. This study underscores the potential for seismic inversion, driven by machine learning techniques, to swiftly and cost-effectively determine critical subsurface parameters like acoustic impedance and porosity. © The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2024.
Covert orienting of attention: An overview
(Indian Academy of Applied Psychology, 2016) Richa Singh; Anurag Upadhyay; Indramani L. Singh
Orienting is a gateway to attention and is defined as aligning of attention with a source of sensory signal. Covert orienting is the shifting of attention without eye or head movement. It enhances performances by detecting the targets faster and more accurately. Posner's location cueing paradigm has been used to study this phenomenon scientifically and it has become one of the most important topics of research in cognitive psychology, cognitive neuropsychology, and cognitive neuroscience. In this paradigm, cue is used to orient the attention covertly where the target is likely to appear. The present paper is an endeavor to systematically define covert orienting, focus on its historical background, study this phenomenon scientifically based on the paradigm used, and explain the factors such as cue type, cue location, cue validity and SOA levels, which affects it and its exogenous and endogenous components. © Journal of the Indian Academy of Applied Psychology.
Curcumin Modulates p62-Keap1-Nrf2-Mediated Autophagy in Rotenone-Induced Parkinson’s Disease Mouse Models
(American Chemical Society, 2022) Aaina Singh Rathore; Saumitra Sen Singh; Hareram Birla; Walia Zahra; Priyanka Kumari Keshri; Hagera Dilnashin; Richa Singh; Shekhar Singh; Surya Pratap Singh
Autophagy mediates self-digestion of abnormally aggregated proteins and organelles present in the cytoplasm. This mechanism may prove to be neuroprotective against Parkinson’s disease (PD) by clearing misfolded α-synuclein (α-syn) aggregates from dopaminergic neurons. p62, an adaptor protein acts as a selective substrate for autophagy and regulates the formation as well as the degradation of protein aggregates. p62 sequesters keap1 freeing Nrf2 and consequently activating the transcription of its target genes. In the present study, we aimed to investigate the anti-parkinsonian activity of curcumin targeting primarily activation of autophagy via the Nrf2-Keap1 pathway. The mice were subcutaneously injected with rotenone (2.5 mg/kg bodyweight) and co-treated with oral administration of curcumin (80 mg/kg bodyweight) for 35 days. Following completion of dosing, motor activities, anti-oxidative potential, mitochondrial dysfunction, and various protein expressions, including Nrf2, Keap1, p62, LC3, Bcl2, Bax, and caspase 3, were assessed. The results revealed that curcumin restored the motor coordination and anti-oxidative activity while improving the mitochondrial functioning in PD mice. Autophagy was evaluated by the change in the expression of autophagic markers, p62 and LC3-II. Reduced p62 and LC3-II expressions in the rotenone mouse model of PD confirmed the compromised autophagy pathway, consequently increasing the aggregation of misfolded protein α-syn. Whereas, curcumin treatment-enhanced autophagy-mediated clearance of misfolded α-syn proteins by increasing the LC3-II expression and blocked apoptotic cascade. Curcumin administration upregulated the Nrf2 expression and normalized the Nrf2-Keap1 pathway, which justifies the improved anti-oxidative activity. Therefore, the findings reveal that curcumin is a Nrf2-inducer and is endowed with neuroprotective potential, which may prove to be a potential candidate for the anti-Parkinson’s disease treatment therapy. © 2023 American Chemical Society.
Development of highly electrocatalytic and electroconducting imprinted film using Ni nanomer for ultra-trace detection of thiamine
(Elsevier B.V., 2017) Bhim Bali Prasad; Richa Singh; Kislay Singh
The present work describes a new molecularly imprinted polymer-based electrochemical sensor for thiamine (vitamin B1), which has been fabricated exploiting both surface imprinting and nanotechnology. Of two monomers used in this work, N-methacryloylglutamic acid served as a biocompatible and bio-adhesive material, whereas the assistant monomer, acryloylated nickel nanoparticles-functionalized multiwalled carbon nanotubes (Ni nanomer) induced large electro-catalytic and conducting activities to the molecularly imprinted polymer film. The polymer synthesis was carried out, following the ‘surface grafting from’ protocol, with the free radical polymerization directly on the surface of Ni nanomer modified pencil graphite electrode. The presence of functionalized-MWCNTs in the polymer film was inevitable to render stability to the coating via aromatic π − π interactions at the film-nanomer modified electrode interface. Thiamine, being electrochemically inactive, was estimated indirectly by a probe, hexamine ruthenium (II) chloride, with signal transduction via differential pulse anodic stripping voltammetric technique. The limits of detection were in the range 0.17–0.2 ng mL−1(S/N = 3) in aqueous, multi-vitamin tablet, urine, and human blood serum, without any cross-reactivity and false- positives. The proposed sensor assures a reliable estimation of thiamine in the patients suffering from its acute deficiency. © 2017
Electrochemical simultaneous analysis of dopamine and epinephrine using double imprinted One MoNomer acryloylated graphene oxide-carbon black composite polymer
(Elsevier Ltd, 2019) Sana Fatma; Bhim Bali Prasad; Swadha Jaiswal; Richa Singh; Kislay Singh
A novel One MoNomer dual imprinted graphene oxide/carbon black composite polymer was developed applying ‘surface-grafting from’ approach on the screen printed carbon electrode for the electrochemical sensing of dopamine and epinephrine. Acryloylated-graphene oxide/carbon black was synthesized for the first time. This served both as a crosslinker and monomer leading to the fast electron transfer from the redox centre to the electrode. The oxidation peak potentials of both the targets were found separated by 200 mV which enabled their simultaneous analysis in real world samples, without any cross reactivity, interferences, and false-positives. The detection limits realized by the proposed sensor, under optimized analytical conditions, were found to be as low as 0.028, 0.028,0.061 and 0.029 ng mL −1 for dopamine and 0.017, 0.018, 0.019 and 0.020 ng mL −1 for epinephrine (S/N = 3) in aqueous, blood serum, urine and pharmaceutical samples. Such sensor could be considered suitable for the primitive diagnosis of several chronic diseases, manifested at ultra-trace level. © 2019
Emission inventory of trace gases from road transport in India
(Elsevier Ltd, 2017) Richa Singh; Chhemendra Sharma; Madhoolika Agrawal
In India, road transport sector is one of the major anthropogenic contributor of GHGs and other pollutants into the atmosphere which have significant adverse human health effects. National and state level pollutants’ emissions from road transport in India have been estimated by using VKT approach for the period of 2001–2013 which includes the values of average vehicle kilometres travelled (VKT) by different vehicle types and emission factors (EF) for different vehicle types. The results revealed a Compound Annual Growth Rate (CAGR) of 8.5%, 8.5%, 8.1%, 8.3%, 8.4%, 8.2% and 9% respectively of carbon dioxide (CO2), methane (CH4), nitrogen oxides (NOx), carbon monoxide (CO), sulphur dioxide (SO2), particulate matters (PM) & hydrocarbon (HC) emissions from vehicles in road transport sector during the periods 2001–2013 due to increase of vehicle population. The study also showed a negative temporal trend in the CO2 emissions per unit of GDP indicating reduced CO2 emission intensities in transport sector. Statewise emission estimates from different vehicle categories confirmed that states like Maharashtra, Gujarat, Tamil Nadu, Kerala, Uttar Pradesh, Rajasthan, Andhra Pradesh, Karnataka and Delhi are responsible for about 68% of total emissions of CO2, CO, CH4, NOx, SO2, HC and PM. © 2017
Enantioselective analysis of D- and L- Serine on a layer-by-layer imprinted electrochemical sensor
(Elsevier Ltd, 2019) Swadha Jaiswal; Richa Singh; Kislay Singh; Sana Fatma; Bhim Bali Prasad
The present work describes a new, simple, and easy method of generating acrylamide functionalised reduced graphene oxide-fullerene layer-by-layer assembled dual imprinted polymers to quantify D- and L-Serine at ultra trace level in aqueous and real samples. Herein, the pencil graphite electrode was initially spin coated with D-Serine imprinted acrylamide functionalized reduced graphene oxide. After 10 min thermal treatment (50 °C), this electrode was again modified with L-Serine imprinted acrylamide functionalized fullerene molecules. This bilayer assembly was finally made thermally stable by 60 °C exposure for 3 h. The proposed sensor showed better electronic properties with an improved synergism. We have compared this modified electrode with other modified pencil graphite electrodes like single layered acrylamide functionalised reduced graphene oxide or fullerene, single layered acrylamide functionalised reduced graphene oxide-fullerene composite and double layered acrylamide functionalised reduced graphene oxide or fullerene molecules, which yielded very inferior sensitivity due to possible agglomeration and decreased synergism. The chosen system demonstrated a very good analytical figures of merit with differential pulse anodic stripping voltammetry and cyclic voltammetry transduction, showing lower limits of detection (0.24 ng mL −1 , S/N = 3) for both isomers. The proposed sensor assures practical applications as disease biomarker, manifesting several diseases at very ultra-trace level. © 2018 Elsevier B.V.
Epigenetic Modulation in Parkinson’s Disease and Potential Treatment Therapies
(Springer, 2021) Aaina Singh Rathore; Hareram Birla; Saumitra Sen Singh; Walia Zahra; Hagera Dilnashin; Richa Singh; Priyanka Kumari Keshri; Surya Pratap Singh
In the recent past, huge emphasis has been given to the epigenetic alterations of the genes responsible for the cause of neurological disorders. Earlier, the scientists believed somatic changes and modifications in the genetic makeup of DNA to be the main cause of the neurodegenerative diseases. With the increase in understanding of the neural network and associated diseases, it was observed that alterations in the gene expression were not always originated by the change in the genetic sequence. For this reason, extensive research has been conducted to understand the role of epigenetics in the pathophysiology of several neurological disorders including Alzheimer’s disease, Parkinson’s disease and, Huntington’s disease. In a healthy person, the epigenetic modifications play a crucial role in maintaining the homeostasis of a cell by either up-regulating or down-regulating the genes. Therefore, improved understanding of these modifications may provide better insight about the diseases and may serve as potential therapeutic targets for their treatment. The present review describes various epigenetic modifications involved in the pathology of Parkinson’s Disease (PD) backed by multiple researches carried out to study the gene expression regulation related to the epigenetic alterations. Additionally, we will briefly go through the current scenario about the various treatment therapies including small molecules and multiple phytochemicals potent enough to reverse these alterations and the future directions for a better management of PD. © 2021, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.
FRESH-based 3D bioprinting of complex biological geometries using chitosan bioink
(Institute of Physics, 2024) Parul Chaurasia; Richa Singh; Sanjeev Kumar Mahto
Traditional three-dimensional (3D) bioprinting has always been associated with the challenge of print fidelity of complex geometries due to the gel-like nature of the bioinks. Embedded 3D bioprinting has emerged as a potential solution to print complex geometries using proteins and polysaccharides-based bioinks. This study demonstrated the Freeform Reversible Embedding of Suspended Hydrogels (FRESH) 3D bioprinting method of chitosan bioink to 3D bioprint complex geometries. 4.5% chitosan was dissolved in an alkali solvent to prepare the bioink. Rheological evaluation of the bioink described its shear-thinning nature. The power law equation was fitted to the shear rate-viscosity plot. The flow index value was found to be less than 1, categorizing the material as pseudo-plastic. The chitosan bioink was extruded into another medium, a thermo-responsive 4.5% gelatin hydrogel. This hydrogel supports the growing print structures while printing. After this, the 3D bioprinted structure was crosslinked with hot water to stabilize the structure. Using this method, we have 3D bioprinted complex biological structures like the human tri-leaflet heart valve, a section of a human right coronary arterial tree, a scale-down outer structure of the human kidney, and a human ear. Additionally, we have shown the mechanical tunability and suturability of the 3D bioprinted structures. This study demonstrates the capability of the chitosan bioink and FRESH method for 3D bioprinting of complex biological models for biomedical applications. © 2024 IOP Publishing Ltd.
HAT and HDAC: Enzyme with Contradictory Action in Neurodegenerative Diseases
(Springer, 2024) Richa Singh; Aaina Singh Rathore; Hagera Dilnashin; Priyanka Kumari Keshri; Nitesh Kumar Gupta; Singh Ankit Satya Prakash; Walia Zahra; Shekhar Singh; Surya Pratap Singh
In view of the increasing risk of neurodegenerative diseases, epigenetics plays a fundamental role in the field of neuroscience. Several modifications have been studied including DNA methylation, histone acetylation, histone phosphorylation, etc. Histone acetylation and deacetylation regulate gene expression, and the regular activity of histone acetyltransferases (HATs) and histone deacetylases (HDACs) provides regulatory stages for gene expression and cell cycle. Imbalanced homeostasis in these enzymes causes a detrimental effect on neurophysiological function. Intriguingly, epigenetic remodelling via histone acetylation in certain brain areas has been found to play a key role in the neurodegenerative diseases such as Alzheimer’s disease, Parkinson’s disease, and Huntington’s disease. It has been demonstrated that a number of HATs have a role in crucial brain processes such regulating neuronal plasticity and memory formation. The most recent therapeutic methods involve the use of small molecules known as histone deacetylase (HDAC) inhibitors that antagonize HDAC activity thereby increase acetylation levels in order to prevent the loss of HAT function in neurodegenerative disorders. The target specificity of the HDAC inhibitors now in use raises concerns about their applicability, despite the fact that this strategy has demonstrated promising therapeutic outcomes. The aim of this review is to summarize the cross-linking between histone modification and its regulation in the pathogenesis of neurological disorders. Furthermore, these findings also support the notion of new pharmacotherapies that target particular areas of the brain using histone deacetylase inhibitors. © The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2024.
Mancozeb-induced genotoxicity and apoptosis in cultured human lymphocytes
(Elsevier Inc., 2012) Amit Kumar Srivastava; Wahid Ali; Richa Singh; Kulpreet Bhui; Shilpa Tyagi; Abdulaziz A. Al-Khedhairy; Pramod Kumar Srivastava; Javed Musarrat; Yogeshwer Shukla
Aims: Mancozeb is a dithiocarbamate fungicide known to be genotoxic and induces tumors in rodents at various sites. There is no report in the literature about its genotoxicity in humans. Here, we investigated the association between mancozeb exposure and induction of genotoxic and proapoptotic changes in cultured human lymphocytes (CHLs). Main methods: Lymphocytes were isolated from peripheral blood of healthy non-smoking donors. Induction of micronuclei and chromosomal aberrations was recorded both by conventional and flow cytometric methods. Annexin-V FITC was used for the differentiation of apoptotic and necrotic cells by flow cytometry. Key findings: Mancozeb exposure (0.5, 2 and 5 μg/ml) to CHLs leads to significant induction in the frequency of chromosomal aberrations (CAs) and micronuclei (MN), in a dose-dependent manner. Concomitantly, pro-oxidant potential of mancozeb was also recorded, by increase in the levels of reactive oxygen species (ROS) generation. Our results demonstrated that ROS plays a critical role in the initiation of mancozeb induced apoptosis in CHLs through two ways, primarily through mitochondria-mediated pathway including induction of ROS, decrease in mitochondrial membrane potential (ΔΨm), along with cytochrome c release from mitochondria, and activation of the caspase cascade. The other pathway includes increase in ROS, which resulted in activation of NF-κB, expression of FasL and triggered FasL-dependent pathway, which also involves caspase-8. Therefore, exposure to mancozeb can lead to induction of apoptosis in CHLs through both mechanisms. Significance: The results of study confirm that mancozeb exposure can induce genotoxicity and apoptosis in CHLs, thus pose a potential risk to exposed human population. © 2012 Elsevier Inc. All rights reserved.
Medicinal Plants and Natural Compounds as Antiparkinsonian Agents
(Bentham Science Publishers, 2022) Walia Zahra; Hareram Birla; Saumitra Sen Singh; Aaina Singh Rathore; Hagera Dilnashin; Richa Singh; Priyanka Kumari Keshri; Surya Pratap Singh
Medicinal plants have been used since ages for the treatment of human diseases in the Indian medicinal system of Ayurveda. Parkinson's diseases (PD) on the other hand is a kind of neurodegenerative disorder that shows debilitating symptoms; and the treatment of the disease rely on the symptomatic management. The drugs available for the treatment of the disease show severe side effects on prolonged usage. Thus, many medicinal plants and their derivative natural compounds have been tested for their anti-Parkinsonian activity with minimal side effects. Mucuna pruriens, Withania somnifera, Tinospora cordifolia are the example of medicinal plants that have shown anti-Parkinsonian activity while the natural compounds found in medicinal plants like Baicalein, curcumin, Ginseng, Resveratol have also maintained the nerve cell function and prevented the neuronal death. Thus, the polyphenols and other bioactive constituent of medicinal plants should be further studied for their therapeutic intervention against PD. © 2022, Bentham Books imprint. All Rights Reserved.
Meta-analysis of polyaromatic hydrocarbons in road dust: An emerging threat in urban environment
(Elsevier B.V., 2024) Richa Singh; Kirpa Ram
Road dust (RD) has emerged as a significant contributor to air pollution in urban areas. It serves as a major reservoir for various contaminants including highly toxic heavy metals and polyaromatic hydrocarbons (PAHs). Therefore, road dust poses threats not only to the environment but also human health, particularly to commuters and residents near roadsides. The abrasion of tyres and the release of carbonaceous materials from vehicle emissions further increases the toxicity of road dust. This study presents a comprehensive review of sources and fate of PAHs in road dust as well as their toxicity in the environment. We have used the Web of Science database from 1989 to 2023. Our study suggests that this research topic has seen a substantial increase in investigations with a rate of ∼40 % since 2008. However, despite an increase in urbanization and industrialization and high toxicity of PAHs in RD, research in developing countries is still limited, primarily due to an inadequate funding and lack of technical advancements. Although atmospheric concentrations of PAHs have declined in developed countries, largely due to the implementation of strict emission standards and air quality regulations, adoption of advanced cleaner fuels and technologies, the demand for transport and energy is more likely to increase in developing countries in the future. Therefore, the study emphasizes the importance of promoting research on RD (size, composition and toxicity) pollution to address and mitigate the impact of PAHs on human health and the environment. Our study highlights that there is a strong need for more research on trade-off between emission and control measures to regulate RD emissions as well as toxic carcinogens including PAHs and heavy metals in urban environment. © 2024 Elsevier B.V.
Microplastic Contamination in the Marine Food Web: Its Impact on Human Health
(wiley, 2022) Richa Singh
Plastics, with their versatile nature of lightweight and high resistance to microbial degradation, work their way into the global human society. Due to their unmanaged disposal, they ultimately reach the ocean. The United Nations Environment Program (2018) has estimated that approximately 13 million tons of plastic enter into the oceans every year. Upon degradation, these plastics are converted to microplastics (MPs) and are distributed to the entire water column, and become part of benthic sediments. They can be found from the Arctic to the Antarctic oceans, and these MPs have a toxicity effect on the marine biota from producer to top consumer when they travel to the successive trophic level of the marine food web. The marine fauna like polychaete, mollusks, fish, birds, mammals, turtles, etc., are often confused with these MPs and their food and consume them, which causes toxicity to them. MPs reach humans through seafood consumption; the impact of MP absorption on the human gastrointestinal tract is relatively lesser when compared with nanoplastics. However, their absorbance and accumulation in the liver and brain are higher among other human organs. Research studies suggest that heavy metal toxicity increases with the MP accumulation in the organism's body. Therefore, the associated toxicity risk is higher with MPs, as they act as a vector for indigenous and nonâ€indigenous species. © 2022 John Wiley & Sons Ltd. All rights reserved.