196 results on '"Parasuraman, Padmanabhan"'
Search Results
2. Revealing the spatiotemporal brain dynamics of covert speech compared with overt speech: A simultaneous EEG-fMRI study
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Wei Zhang, Muyun Jiang, Kok Ann Colin Teo, Raghavan Bhuvanakantham, LaiGuan Fong, Wei Khang Jeremy Sim, Zhiwei Guo, Chuan Huat Vince Foo, Rong Hui Jonathan Chua, Parasuraman Padmanabhan, Victoria Leong, Jia Lu, Balázs Gulyás, and Cuntai Guan
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Covert speech ,Overt speech ,Simultaneous EEG-fMRI ,Left putamen ,Functional connectivity ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
Covert speech (CS) refers to speaking internally to oneself without producing any sound or movement. CS is involved in multiple cognitive functions and disorders. Reconstructing CS content by brain-computer interface (BCI) is also an emerging technique. However, it is still controversial whether CS is a truncated neural process of overt speech (OS) or involves independent patterns. Here, we performed a word-speaking experiment with simultaneous EEG-fMRI. It involved 32 participants, who generated words both overtly and covertly. By integrating spatial constraints from fMRI into EEG source localization, we precisely estimated the spatiotemporal dynamics of neural activity. During CS, EEG source activity was localized in three regions: the left precentral gyrus, the left supplementary motor area, and the left putamen. Although OS involved more brain regions with stronger activations, CS was characterized by an earlier event-locked activation in the left putamen (peak at 262 ms versus 1170 ms). The left putamen was also identified as the only hub node within the functional connectivity (FC) networks of both OS and CS, while showing weaker FC strength towards speech-related regions in the dominant hemisphere during CS. Path analysis revealed significant multivariate associations, indicating an indirect association between the earlier activation in the left putamen and CS, which was mediated by reduced FC towards speech-related regions. These findings revealed the specific spatiotemporal dynamics of CS, offering insights into CS mechanisms that are potentially relevant for future treatment of self-regulation deficits, speech disorders, and development of BCI speech applications.
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- 2024
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3. Molecular imaging of bacterial outer membrane vesicles based on bacterial surface display
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Dávid Szöllősi, Polett Hajdrik, Hedvig Tordai, Ildikó Horváth, Dániel S. Veres, Bernadett Gillich, Kanni Das Shailaja, László Smeller, Ralf Bergmann, Michael Bachmann, Judith Mihály, Anikó Gaál, Bálint Jezsó, Balázs Barátki, Dorottya Kövesdi, Szilvia Bősze, Ildikó Szabó, Tamás Felföldi, Erzsébet Oszwald, Parasuraman Padmanabhan, Balázs Zoltán Gulyás, Nazha Hamdani, Domokos Máthé, Zoltán Varga, and Krisztián Szigeti
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Medicine ,Science - Abstract
Abstract The important roles of bacterial outer membrane vesicles (OMVs) in various diseases and their emergence as a promising platform for vaccine development and targeted drug delivery necessitates the development of imaging techniques suitable for quantifying their biodistribution with high precision. To address this requirement, we aimed to develop an OMV specific radiolabeling technique for positron emission tomography (PET). A novel bacterial strain (E. coli BL21(DE3) ΔnlpI, ΔlpxM) was created for efficient OMV production, and OMVs were characterized using various methods. SpyCatcher was anchored to the OMV outer membrane using autotransporter-based surface display systems. Synthetic SpyTag-NODAGA conjugates were tested for OMV surface binding and 64Cu labeling efficiency. The final labeling protocol shows a radiochemical purity of 100% with a ~ 29% radiolabeling efficiency and excellent serum stability. The in vivo biodistribution of OMVs labeled with 64Cu was determined in mice using PET/MRI imaging which revealed that the biodistribution of radiolabeled OMVs in mice is characteristic of previously reported data with the highest organ uptakes corresponding to the liver and spleen 3, 6, and 12 h following intravenous administration. This novel method can serve as a basis for a general OMV radiolabeling scheme and could be used in vaccine- and drug-carrier development based on bioengineered OMVs.
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- 2023
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4. Mitochondrial Reactive Oxygen Species in Infection and Immunity
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Arunima Mukherjee, Krishna Kanta Ghosh, Sabyasachi Chakrabortty, Balázs Gulyás, Parasuraman Padmanabhan, and Writoban Basu Ball
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mitochondrial reactive oxygen species ,electron transport chain ,inflammasome ,bacteria ,protozoa ,virus ,Microbiology ,QR1-502 - Abstract
Reactive oxygen species (ROS) contain at least one oxygen atom and one or more unpaired electrons and include singlet oxygen, superoxide anion radical, hydroxyl radical, hydroperoxyl radical, and free nitrogen radicals. Intracellular ROS can be formed as a consequence of several factors, including ultra-violet (UV) radiation, electron leakage during aerobic respiration, inflammatory responses mediated by macrophages, and other external stimuli or stress. The enhanced production of ROS is termed oxidative stress and this leads to cellular damage, such as protein carbonylation, lipid peroxidation, deoxyribonucleic acid (DNA) damage, and base modifications. This damage may manifest in various pathological states, including ageing, cancer, neurological diseases, and metabolic disorders like diabetes. On the other hand, the optimum levels of ROS have been implicated in the regulation of many important physiological processes. For example, the ROS generated in the mitochondria (mitochondrial ROS or mt-ROS), as a byproduct of the electron transport chain (ETC), participate in a plethora of physiological functions, which include ageing, cell growth, cell proliferation, and immune response and regulation. In this current review, we will focus on the mechanisms by which mt-ROS regulate different pathways of host immune responses in the context of infection by bacteria, protozoan parasites, viruses, and fungi. We will also discuss how these pathogens, in turn, modulate mt-ROS to evade host immunity. We will conclude by briefly giving an overview of the potential therapeutic approaches involving mt-ROS in infectious diseases.
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- 2024
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5. Multifunctional Nanoparticles and Nanoclusters as a Theranostics and Symptoms Disappearing Agent for Traumatic Brain Injury
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Fong LaiGuan Zoey, Krishna Kanta Ghosh, Mathangi Palanivel, Balázs Gulyás, and Parasuraman Padmanabhan
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multifunctional ,nanotechnology ,neuroprotective ,theranostic ,traumatic brain injury ,Biotechnology ,TP248.13-248.65 ,Medical technology ,R855-855.5 - Abstract
Traumatic brain injury (TBI) is one of the most common causes of disability and mortality worldwide, creating a large socioeconomic burden annually. Secondary injury physiopathology is known to play a prominent role in exacerbating neurodegeneration post‐TBI and is potentially preventable by therapies. However, due to the heterogeneity of TBI and the complexity of the pathological mechanisms that ensue, there are currently no effective disease‐modifying treatments to prevent TBI‐associated disability and mortality. Nanotechnology has emerged in recent decades as a promising platform for the development of multifunctional neuroprotective agents for TBI. Herein, current multifunctional innovations are explored in this review in nanotechnology, which target the secondary injury pathological mechanisms of TBI and show promise in improving future post‐TBI management. Also, potential new directions for the future development of TBI treatment are discussed.
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- 2023
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6. Radiolabeling of Platelets with 99mTc-HYNIC-Duramycin for In Vivo Imaging Studies
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Keresztély Merkel, Dávid Szöllősi, Ildikó Horváth, Bálint Jezsó, Zsolt Baranyai, Krisztián Szigeti, Zoltán Varga, Imre Hegedüs, Parasuraman Padmanabhan, Balázs Gulyás, Ralf Bergmann, and Domokos Máthé
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platelet radiolabeling ,99mTc-HYNIC-Duramycin ,SPECT ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
Following the in vivo biodistribution of platelets can contribute to a better understanding of their physiological and pathological roles, and nuclear imaging methods, such as single photon emission tomography (SPECT), provide an excellent method for that. SPECT imaging needs stable labeling of the platelets with a radioisotope. In this study, we report a new method to label platelets with 99mTc, the most frequently used isotope for SPECT in clinical applications. The proposed radiolabeling procedure uses a membrane-binding peptide, duramycin. Our results show that duramycin does not cause significant platelet activation, and radiolabeling can be carried out with a procedure utilizing a simple labeling step followed by a size-exclusion chromatography-based purification step. The in vivo application of the radiolabeled human platelets in mice yielded quantitative biodistribution images of the spleen and liver and no accumulation in the lungs. The performed small-animal SPECT/CT in vivo imaging investigations revealed good in vivo stability of the labeling, which paves the way for further applications of 99mTc-labeled-Duramycin in platelet imaging.
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- 2023
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7. Correction: Synthesis and preclinical application of a Prussian blue-based dual fluorescent and magnetic contrast agent (CA).
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Nikolett Hegedűs, László Forgách, Bálint Kiss, Zoltán Varga, Bálint Jezsó, Ildikó Horváth, Noémi Kovács, Polett Hajdrik, Parasuraman Padmanabhan, Balázs Gulyás, Krisztián Szigeti, and Domokos Máthé
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Medicine ,Science - Abstract
[This corrects the article DOI: 10.1371/journal.pone.0264554.].
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- 2023
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8. Structural Characterization, Antimicrobial, Antibiofilm, Antioxidant, Anticancer and Acute Toxicity Properties of N-(2-hydroxyphenyl)-2-phenazinamine From Nocardiopsis exhalans (KP149558)
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Vaikundamoorthy Ramalingam, Rajendran Rajaram, Govindaraju Archunan, Parasuraman Padmanabhan, and Balázs Gulyás
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Nocardiopsis exhalans ,antimicrobial ,antibiofilm ,antioxidant ,anticancer ,acute toxicity ,Microbiology ,QR1-502 - Abstract
The present study aimed to isolate and identify potential drugs from marine actinomycete Nocardiopsis exhalans and screen them for biomedical applications. The cell-free culture of N. exhalans was extracted with ethyl acetate and the solvent extract showed six fractions in thin-layer chromatography. The fractions were subjected to column chromatography for purification and evaluated for activity against human clinical pathogens. Fraction 4 showed significant activity and was identified as N-(2-hydroxyphenyl)-2-phenazinamine (NHP) using spectral analyses. Further, NHP showed excellent biofilm inhibitory activity against human clinical pathogens Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus. The in vitro antioxidant activity confirmed that NHP is scavenging the oxidative stress-enhancing molecules. The anti-proliferative activity of NHP against human breast cancer cells showed significant activity at 300 µg/ml and less cytotoxic activity against normal cells. Additionally, the toxicity assessment against zebrafish revealed that NHP does not cause any toxicity in the important organs. The results highlight N. exhalans as a promising candidate for the development of antibiotics with potential therapeutic applications.
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- 2022
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9. Surface Ligand Influences the Cu Nanoclusters as a Dual Sensing Optical Probe for Localized pH Environment and Fluoride Ion
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Kumar Babu Busi, Subhalaxmi Das, Mathangi Palanivel, Krishna Kanta Ghosh, Balázs Gulyás, Parasuraman Padmanabhan, and Sabyasachi Chakrabortty
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copper nanoclusters ,bovine serum albumin ,L-cysteine ,pH sensor ,fluoride ion detection ,Chemistry ,QD1-999 - Abstract
Functional metal nanomaterials, especially in the nanocluster (NC) size regime, with strong fluorescence, aqueous colloidal stability, and low toxicity, necessitate their application potential in biology and environmental science. Here, we successfully report a simple cost-effective method for red-/green-color-emitting protein/amino-acid-mediated Cu NCs in an aqueous medium. As-synthesized Cu NCs were characterized through UV-Vis absorption spectroscopy, fluorescence spectroscopy, time-resolved photoluminescence, dynamic light scattering, zeta potential, transmission electron microscopy and X-ray photoelectron spectroscopy. The optical properties of both Cu NCs responded linearly to the variation in pH in the neutral and alkaline ranges, and a robust pH reversible nature (between pH 7 and 11) was observed that could be extended to rapid, localized pH sensor development. However, a contrasting pH response nature between protein–Cu NCs and amino acid–Cu NCs was recorded. The alteration in protein secondary structure and strong binding nature of the surfactants were suggested to explain this behavior. Furthermore, we investigated their use as an efficient optical probe for fluoride ion detection. The limit of detection for protein–Cu NCs is 6.74 µM, whereas the limit of detection for amino acid–Cu NCs is 4.67 µM. Thus, it is anticipated that ultrasmall Cu NCs will exhibit promise in biological and environmental sensing applications.
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- 2023
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10. Altered striatal dopamine levels in Parkinson’s disease VPS35 D620N mutant transgenic aged mice
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Sarivin Vanan, Xiaoxia Zeng, Sook Yoong Chia, Katarina Varnäs, Mei Jiang, Ke Zhang, Wuan Ting Saw, Parasuraman Padmanabhan, Wei-Ping Yu, Zhi-Dong Zhou, Christer Halldin, Balázs Gulyás, Eng-King Tan, and Li Zeng
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Parkinson’s disease ,VPS35 D620N ,Striatal dopamine ,Transgenic mice ,Behavioral assay ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
Abstract Vacuolar protein sorting 35 (VPS35) is a major component of the retromer complex that mediates the retrograde transport of cargo proteins from endosomes to the trans-Golgi network. Mutations such as D620N in the VPS35 gene have been identified in patients with autosomal dominant Parkinson’s disease (PD). However, it remains poorly understood whether and how VPS35 deficiency or mutation contributes to PD pathogenesis; specifically, the studies that have examined VPS35 thus far have differed in results and methodologies. We generated a VPS35 D620N mouse model using a Rosa26-based transgene expression platform to allow expression in a spatial manner, so as to better address these discrepancies. Here, aged (20-months-old) mice were first subjected to behavioral tests. Subsequently, DAB staining analysis of substantia nigra (SN) dopaminergic neurons with the marker for tyrosine hydroxylase (TH) was performed. Next, HPLC was used to determine dopamine levels, along with levels of its two metabolites, 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA), in the striatum. Western blotting was also performed to study the levels of key proteins associated with PD. Lastly, autoradiography (ARG) evaluation of [3H]FE-PE2I binding to the striatal dopamine transporter DAT was carried out. We found that VPS35 D620N Tg mice displayed a significantly higher dopamine level than NTg counterparts. All results were then compared with that of current VPS35 studies to shed light on the disease pathogenesis. Our model allows future studies to explicitly control spatial expression of the transgene which would generate a more reliable PD phenotype.
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- 2020
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11. Synthesis and preclinical application of a Prussian blue-based dual fluorescent and magnetic contrast agent (CA).
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Nikolett Hegedűs, László Forgách, Bálint Kiss, Zoltán Varga, Bálint Jezsó, Ildikó Horváth, Noémi Kovács, Polett Hajdrik, Parasuraman Padmanabhan, Balázs Gulyás, Krisztián Szigeti, and Domokos Máthé
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Medicine ,Science - Abstract
The aim of this study was to develop and characterize a Prussian Blue based biocompatible and chemically stable T1 magnetic resonance imaging (MRI) contrast agent with near infrared (NIR) optical contrast for preclinical application. The physical properties of the Prussian blue nanoparticles (PBNPs) (iron (II); iron (III);octadecacyanide) were characterized with dynamic light scattering (DLS), zeta potential measurement, atomic force microscopy (AFM), and transmission electron microscopy (TEM). In vitro contrast enhancement properties of PBNPs were determined by MRI. In vivo T1-weighted contrast of the prepared PBNPs was investigated by MRI and optical imaging modality after intravenous administration into NMRI-Foxn1 nu/nu mice. The biodistribution studies showed the presence of PBNPs predominantly in the cardiovascular system. Briefly, in this paper we show a novel approach for the synthesis of PBNPs with enhanced iron content for T1 MRI contrast. This newly synthetized PBNP platform could lead to a new diagnostic agent, replacing the currently used Gadolinium based substances.
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- 2022
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12. Dealing with PET radiometabolites
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Krishna Kanta Ghosh, Parasuraman Padmanabhan, Chang-Tong Yang, Sachin Mishra, Christer Halldin, and Balázs Gulyás
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Radiometabolites ,PET ,HPLC ,Radiotracer ,HPLC-MS ,Medical physics. Medical radiology. Nuclear medicine ,R895-920 - Abstract
Abstract Positron emission tomography (PET) offers the study of biochemical, physiological, and pharmacological functions at a cellular and molecular level. The performance of a PET study mostly depends on the used radiotracer of interest. However, the development of a novel PET tracer is very difficult, as it is required to fulfill a lot of important criteria. PET radiotracers usually encounter different chemical modifications including redox reaction, hydrolysis, decarboxylation, and various conjugation processes within living organisms. Due to this biotransformation, different chemical entities are produced, and the amount of the parent radiotracer is declined. Consequently, the signal measured by the PET scanner indicates the entire amount of radioactivity deposited in the tissue; however, it does not offer any indication about the chemical disposition of the parent radiotracer itself. From a radiopharmaceutical perspective, it is necessary to quantify the parent radiotracer’s fraction present in the tissue. Hence, the identification of radiometabolites of the radiotracers is vital for PET imaging. There are mainly two reasons for the chemical identification of PET radiometabolites: firstly, to determine the amount of parent radiotracers in plasma, and secondly, to rule out (if a radiometabolite enters the brain) or correct any radiometabolite accumulation in peripheral tissue. Besides, radiometabolite formations of the tracer might be of concern for the PET study, as the radiometabolic products may display considerably contrasting distribution patterns inside the body when compared with the radiotracer itself. Therefore, necessary information is needed about these biochemical transformations to understand the distribution of radioactivity throughout the body. Various published review articles on PET radiometabolites mainly focus on the sample preparation techniques and recently available technology to improve the radiometabolite analysis process. This article essentially summarizes the chemical and structural identity of the radiometabolites of various radiotracers including [11C]PBB3, [11C]flumazenil, [18F]FEPE2I, [11C]PBR28, [11C]MADAM, and (+)[18F]flubatine. Besides, the importance of radiometabolite analysis in PET imaging is also briefly summarized. Moreover, this review also highlights how a slight chemical modification could reduce the formation of radiometabolites, which could interfere with the results of PET imaging. Graphical abstract
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- 2020
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13. Parkinson’s Disease: A Nanotheranostic Approach Targeting Alpha-Synuclein Aggregation
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Fong LaiGuan Zoey, Mathangi Palanivel, Parasuraman Padmanabhan, and Balázs Gulyás
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alpha-synuclein ,Parkinson’s disease ,magnetic resonance imaging ,nanotechnology ,nanoparticle ,diagnostic ,Biology (General) ,QH301-705.5 - Abstract
Parkinson’s disease (PD) is one of the most common neurodegenerative disorders that is implicated in aging populations. As numerous developed nations are experiencing progressively aging populations today, there is a heightened propensity for the occurrence of PD cases. Alpha-synuclein (α-syn) aggregation has been considered to be the pivotal mechanism leading to PD pathogenesis. Thus, early diagnostic and therapeutic strategies targeting the misfolded α-syn protein can potentially improve the prognosis of PD. With rapid advancements in nanotechnology in the last decade, effective solutions to various neurodegenerative and oncological diseases have been suggested. This review will explore the current innovations in nanotechnology that target the α-syn aggregation pathway, and reinstate the promise they hold as effective early diagnostic and therapeutic solutions to PD.
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- 2021
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14. The Utilization of Physiologically Active Molecular Components of Grape Seeds and Grape Marc
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Imre Hegedüs, Kitti Andreidesz, József L. Szentpéteri, Zoltán Kaleta, László Szabó, Krisztián Szigeti, Balázs Gulyás, Parasuraman Padmanabhan, Ferenc Budan, and Domokos Máthé
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grape ,polyphenols ,flavonoids ,anticarcinogen ,vasoprotective ,antidiabetic ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
Nutritional interventions may highly contribute to the maintenance or restoration of human health. Grapes (Vitis vinifera) are one of the oldest known beneficial nutritional components of the human diet. Their high polyphenol content has been proven to enhance human health beyond doubt in statistics-based public health studies, especially in the prevention of cardiovascular disease and cancer. The current review concentrates on presenting and classifying polyphenol bioactive molecules (resveratrol, quercetin, catechin/epicatechin, etc.) available in high quantities in Vitis vinifera grapes or their byproducts. The molecular pathways and cellular signaling cascades involved in the effects of these polyphenol molecules are also presented in this review, which summarizes currently available in vitro and in vivo experimental literature data on their biological activities mostly in easily accessible tabular form. New molecules for different therapeutic purposes can also be synthesized based on existing polyphenol compound classes available in high quantities in grape, wine, and grape marc. Therefore an overview of these molecular structures is provided. Novel possibilities as dendrimer nanobioconjugates are reviewed, too. Currently available in vitro and in vivo experimental literature data on polyphenol biological activities are presented in easily accessible tabular form. The scope of the review details the antidiabetic, anticarcinogenic, antiviral, vasoprotective, and neuroprotective roles of grape-origin flavonoids. The novelty of the study lies in the description of the processing of agricultural by-products (grape seeds and skins) of industrial relevance, and the detailed description of the molecular mechanisms of action. In addition, the review of the clinical therapeutic applications of polyphenols is unique as no summary study has yet been done.
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- 2022
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15. Biomedical and Textile Applications of Alternanthera sessilis Leaf Extract Mediated Synthesis of Colloidal Silver Nanoparticle
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Nivedhitha Kabeerdass, Karthikeyan Murugesan, Natarajan Arumugam, Abdulrahman I. Almansour, Raju Suresh Kumar, Sinouvassane Djearamane, Ashok Kumar Kumaravel, Palanivel Velmurugan, Vinayagam Mohanavel, Subbiah Suresh Kumar, Selvaraj Vijayanand, Parasuraman Padmanabhan, Balázs Gulyás, and Maghimaa Mathanmohun
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plant extract ,antibacterial ,SEM with EDAX ,HR-TEM ,fabrics ,Chemistry ,QD1-999 - Abstract
The aqueous extract of Alternanthera sessilis (As) acts as the precursors for the quick reduction of silver ions, which leads to the formation of silver nanoparticles. In the agar, well diffusion method of the Klebsiella pneumoniae shows the minimal inhibitory concentration of 12 mm against A. sessilis mediated silver nanoparticles (As-AgNPs) at 60 µg/mL concentration. Fabric treated with novel AS-AgNPs is tested against the K. pneumoniae and shows an inhibitory action of 12 mm with mixed cotton that determines the antimicrobial efficacy of the fabrics. Uv- visible spectrophotometer was performed, showing a surface plasmon resonance peak at 450 nm cm−1. FTIR shows the vibration and the infrared radiation at a specific wavelength of 500–4000 cm−1. The HR-TEM analysis showed the presence of black-white crystalline, spherical-shaped As-AgNPs embedded on the fabrics range of 15 nm–40 nm. In the scanning electron microscope, the presence of small ball-shaped As-AgNPs embedded on the fabrics at a voltage of 30 KV was found with a magnification of 578X. EDAX was performed in which the nanoparticles show a peak of 2.6–3.9 KeV, and it also reveals the presence of the composition, distribution, and elemental mapping of the nanoparticles. The cytotoxic activity of synthesized nanosilver was carried out against L929 cell lines, which show cell viability at a concentration of 2.5 µg mL−1. Cell proliferation assay shows no cytotoxicity against L929 cell lines for 24 h. In this study, the green synthesis of silver nanoparticles from A. sessilis appears to be a cheap, eco-friendly, and alternative approach for curing infectious ulcers on the floor of the stratum corneum. Nanotechnology conjoined with herbal therapeutics provides a promising solution for wound management.
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- 2022
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16. A Brief Introduction to Magnetoencephalography (MEG) and Its Clinical Applications
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Alfred Lenin Fred, Subbiahpillai Neelakantapillai Kumar, Ajay Kumar Haridhas, Sayantan Ghosh, Harishita Purushothaman Bhuvana, Wei Khang Jeremy Sim, Vijayaragavan Vimalan, Fredin Arun Sedly Givo, Veikko Jousmäki, Parasuraman Padmanabhan, and Balázs Gulyás
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magnetoencephalography (MEG) ,clinical application ,brain network ,brain connectivity ,neurological disorder ,electrophysiology ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
Magnetoencephalography (MEG) plays a pivotal role in the diagnosis of brain disorders. In this review, we have investigated potential MEG applications for analysing brain disorders. The signal-to-noise ratio (SNRMEG = 2.2 db, SNREEG < 1 db) and spatial resolution (SRMEG = 2–3 mm, SREEG = 7–10 mm) is higher for MEG than EEG, thus MEG potentially facilitates accurate monitoring of cortical activity. We found that the direct electrophysiological MEG signals reflected the physiological status of neurological disorders and play a vital role in disease diagnosis. Single-channel connectivity, as well as brain network analysis, using MEG data acquired during resting state and a given task has been used for the diagnosis of neurological disorders such as epilepsy, Alzheimer’s, Parkinsonism, autism, and schizophrenia. The workflow of MEG and its potential applications in the diagnosis of disease and therapeutic planning are also discussed. We forecast that computer-aided algorithms will play a prominent role in the diagnosis and prediction of neurological diseases in the future. The outcome of this narrative review will aid researchers to utilise MEG in diagnostics.
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- 2022
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17. 3D Deep Learning on Medical Images: A Review.
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Satya Prakash Singh, Lipo Wang, Sukrit Gupta, Haveesh Goli, Parasuraman Padmanabhan, and Balázs Gulyás
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- 2020
18. The Exoproteome of Staphylococcus pasteuri Isolated from Cervical Mucus during the Estrus Phase in Water Buffalo (Bubalus bubalis)
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Mahalingam Srinivasan, Subramanian Muthukumar, Durairaj Rajesh, Vinod Kumar, Rajamanickam Rajakumar, Mohammad Abdulkader Akbarsha, Balázs Gulyás, Parasuraman Padmanabhan, and Govindaraju Archunan
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extracellular proteins ,enolase ,cpn60 ,lipoprotein ,chemical communication ,microbes ,Microbiology ,QR1-502 - Abstract
Bacterial extracellular proteins participate in the host cell communication by virtue of the modulation of pathogenicity, commensalism and mutualism. Studies on the microbiome of cervical mucus of the water buffalo (Bubalus bubalis) have shown the occurrence of Staphylococcus pasteuri and that the presence of this bacterium is indicative of various physiological and reproductive states in the host. Recently, S. pasteuri has been isolated from the cervical mucus of the buffalo during the different phases of estrous cycle, and has proved to be much more pronounced during the estrus phase. The basis underlying the availability of a significantly increased S. pasteuri population, specifically during the estrus phase, is not known. Consequently, it is important to determine the significance of the specific abundance of S. pasteuri during the estrus phase of the buffalo host, particularly from the perspective of whether this bacterial species is capable of contributing to sexual communication via its extracellular proteins and volatiles. Therefore, the relevance of S. pasteuri exoproteome in the buffalo cervical mucus during the estrus phase was analyzed using LC-MS/MS. As many as 219 proteins were identified, among which elongation factor Tu (EF-Tu), 60-kDa chaperonin (Cpn60), enolase, fructose-bisphosphate aldolase class 1 (FBP aldolase), enoyl-[acyl-carrier-protein] reductase [NADPH] (ENR) and lipoprotein (Lpp) were the functionally important candidates. Most of the proteins present in the exoproteome of S. pasteuri were those involved in cellular–metabolic functions, as well as catalytic- and binding activities. Moreover, computational studies of Lpp have shown enhanced interaction with volatiles such as acetic-, butanoic-, isovaleric- and valeric acids, which were identified in the cervical mucus S. pasteuri culture supernatant. The present findings suggest that S. pasteuri extracellular proteins may play an important role in buffalo sexual communication during the estrus phase.
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- 2022
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19. Gadolinium and Polythiophene Functionalized Polyurea Polymer Dots as Fluoro-Magnetic Nanoprobes
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Soner Karabacak, Alagappan Palaniappan, Tsang Siu Hon Tony, Teo Hang Tong Edwin, Balázs Gulyás, Parasuraman Padmanabhan, and Ümit Hakan Yildiz
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dual-functional reporters ,PTAA ,polymer dots ,polyurea Pdots ,mini-emulsion polymerization ,magnetic manipulation ,Chemistry ,QD1-999 - Abstract
A rapid and one-pot synthesis of poly 3-thiopheneacetic acid (PTAA) functionalized polyurea polymer dots (Pdots) using polyethyleneimine and isophorone diisocyanate is reported. The one-pot mini-emulsion polymerization technique yielded Pdots with an average diameter of ~20 nm. The size, shape, and concentration of the surface functional groups could be controlled by altering the synthesis parameters such as ultrasonication time, concentration of the surfactant, and crosslinking agent, and the types of isocyanates utilized for the synthesis. Colloidal properties of Pdots were characterized using dynamic light scattering and zeta potential measurements. The spherical geometry of Pdots was confirmed by scanning electron microscopy. The Pdots were post-functionalized by 1,4,7,10 tetraazacyclododecane-1,4,7,10-tetraacetic acid for chelating gadolinium nanoparticles (Gd3+) that provide magnetic properties to the Pdots. Thus, the synthesized Pdots possess fluorescent and magnetic properties, imparted by PTAA and Gd3+, respectively. Fluorescence spectroscopy and microscopy revealed that the synthesized dual-functional Gd3+-Pdots exhibited detectable fluorescent signals even at lower concentrations. Magnetic levitation experiments indicated that the Gd3+-Pdots could be easily manipulated via an external magnetic field. These findings illustrate that the dua- functional Gd3+-Pdots could be potentially utilized as fluorescent reporters that can be magnetically manipulated for bioimaging applications.
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- 2022
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20. The Multifarious Applications of Copper Nanoclusters in Biosensing and Bioimaging and Their Translational Role in Early Disease Detection
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Kumar Babu Busi, Mathangi Palanivel, Krishna Kanta Ghosh, Writoban Basu Ball, Balázs Gulyás, Parasuraman Padmanabhan, and Sabyasachi Chakrabortty
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noble metals ,copper nanoclusters ,fluorescence ,diagnostics ,theranostics ,bioimaging ,Chemistry ,QD1-999 - Abstract
Nanoclusters possess an ultrasmall size, amongst other favorable attributes, such as a high fluorescence and long-term colloidal stability, and consequently, they carry several advantages when applied in biological systems for use in diagnosis and therapy. Particularly, the early diagnosis of diseases may be facilitated by the right combination of bioimaging modalities and suitable probes. Amongst several metallic nanoclusters, copper nanoclusters (Cu NCs) present advantages over gold or silver NCs, owing to their several advantages, such as high yield, raw abundance, low cost, and presence as an important trace element in biological systems. Additionally, their usage in diagnostics and therapeutic modalities is emerging. As a result, the fluorescent properties of Cu NCs are exploited for use in optical imaging technology, which is the most commonly used research tool in the field of biomedicine. Optical imaging technology presents a myriad of advantages over other bioimaging technologies, which are discussed in this review, and has a promising future, particularly in early cancer diagnosis and imaging-guided treatment. Furthermore, we have consolidated, to the best of our knowledge, the recent trends and applications of copper nanoclusters (Cu NCs), a class of metal nanoclusters that have been gaining much traction as ideal bioimaging probes, in this review. The potential modes in which the Cu NCs are used for bioimaging purposes (e.g., as a fluorescence, magnetic resonance imaging (MRI), two-photon imaging probe) are firstly delineated, followed by their applications as biosensors and bioimaging probes, with a focus on disease detection.
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- 2022
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21. Mollification of Doxorubicin (DOX)-Mediated Cardiotoxicity Using Conjugated Chitosan Nanoparticles with Supplementation of Propionic Acid
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Durairaj Siva, Subramanian Abinaya, Durairaj Rajesh, Govindaraju Archunan, Parasuraman Padmanabhan, Balázs Gulyás, and Shanmugam Achiraman
- Subjects
doxorubicin ,PPARγ ,chitosan nanoparticles ,cardiotoxicity ,propionic acid ,Chemistry ,QD1-999 - Abstract
Doxorubicin is an extensively prescribed antineoplastic agent. It is also known for adverse effects, among which cardiotoxicity tops the list. The possible mechanism underlying doxorubicin (DOX)-mediated cardiotoxicity has been investigated in this study. Further, to reduce the DOX-mediated cardiotoxicity, DOX was conjugated with Chitosan Nanoparticles (DCNPs) and supplemented with propionic acid. Initially, the drug loading efficacy and conjugation of DOX with chitosan was confirmed by UV–Visible Spectroscopy (UV) and Fourier Transform Infrared Spectroscopy (FTIR). The average sizes of the synthesized Chitosan Nanoparticles (CNPs) and DCNPs were measured by Dynamic Light Scattering (DLS) analysis as 187.9 ± 1.05 nm and 277.3 ± 8.15 nm, respectively, and the zeta potential values were recorded as 55.2 ± 0.7 mV and 51.9 ± 1.0 mV, respectively. The size and shape of CNPs and DCNPs were recorded using a High-Resolution Electron Microscopy (HRTEM). The particles measured
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- 2022
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22. Role of Digital Twin Technology in Medical Sector—Toward Ensuring Safe Healthcare
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S.N. Kumar, A. Lenin Fred, L.R. Jonisha Miriam, Jane I. Christina, H. Ajay Kumar, Parasuraman Padmanabhan, and Balazs Gulyas
- Published
- 2022
23. PET/MRI: a frontier in era of complementary hybrid imaging
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Sikkandhar Musafargani, Krishna Kanta Ghosh, Sachin Mishra, Pachaiyappan Mahalakshmi, Parasuraman Padmanabhan, and Balázs Gulyás
- Subjects
Multi-modal imaging ,Hybrid modality ,PET/MRI ,Attenuation correction ,Image reconstruction ,Medical physics. Medical radiology. Nuclear medicine ,R895-920 - Abstract
Abstract With primitive approaches, the diagnosis and therapy were operated at the cellular, molecular, or even at the genetic level. As the diagnostic techniques are more concentrated towards molecular level, multi modal imaging becomes specifically essential. Multi-modal imaging has extensive applications in clinical as well as in pre-clinical studies. Positron Emission Tomography (PET) has flourished in the field of nuclear medicine, which has motivated it to fuse with Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) for PET/CT and PET/MRI respectively. However, the challenges in PET/CT are due to the inability of simultaneous acquisition and reduced soft tissue contrast, which has led to the development of PET/MRI. Also, MRI offers the better soft tissue contrast over CT. Hence, fusion of PET and MRI results in combining structural information with functional image from PET. Yet, it has many technical challenges due to the interference between the modalities. Also, it must be resolved with various approaches for addressing the shortcomings of each system and improvise on the image quantification system. This review elaborates on the various challenges in the present PET/MRI system and the future directions of the hybrid modality. Also, the different data acquisition and analysis techniques of PET/MRI system are discussed with enhanced details on the software tools.
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- 2018
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24. Anticancer Potential of L-Histidine-Capped Silver Nanoparticles against Human Cervical Cancer Cells (SiHA)
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Rajmohamed Mohammed Asik, Chidhambaram Manikkaraja, Karuppusamy Tamil Surya, Natarajan Suganthy, Archunan Priya Aarthy, Domokos Mathe, Muthusamy Sivakumar, Govindaraju Archunan, Parasuraman Padmanabhan, and Balazs Gulyas
- Subjects
anticancer activity ,L-histidine ,silver nanoparticles ,cervical cancer cells ,apoptosis ,Chemistry ,QD1-999 - Abstract
This study reports the synthesis of silver nanoparticles using amino acid L-histidine as a reducing and capping agent as an eco-friendly approach. Fabricated L-histidine-capped silver nanoparticles (L-HAgNPs) were characterized by spectroscopic and microscopic studies. Spherical shaped L-HAgNPs were synthesized with a particle size of 47.43 ± 19.83 nm and zeta potential of −20.5 ± 0.95 mV. Results of the anticancer potential of L-HAgNPs showed antiproliferative effect against SiHa cells in a dose-dependent manner with an IC50 value of 18.25 ± 0.36 µg/mL. Fluorescent microscopic analysis revealed L-HAgNPs induced reactive oxygen species (ROS) mediated mitochondrial dysfunction, leading to activation of apoptotic pathway and DNA damage eventually causing cell death. To conclude, L-HAgNPs can act as promising candidates for cervical cancer therapy.
- Published
- 2021
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25. Brain–Computer Interfacing Using Functional Near-Infrared Spectroscopy (fNIRS)
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Kogulan Paulmurugan, Vimalan Vijayaragavan, Sayantan Ghosh, Parasuraman Padmanabhan, and Balázs Gulyás
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functional near-infrared spectroscopy (fNIRS) ,non-invasive monitoring ,brain function ,neuron function ,blood oxygen concentration ,cognitive function ,Biotechnology ,TP248.13-248.65 - Abstract
Functional Near-Infrared Spectroscopy (fNIRS) is a wearable optical spectroscopy system originally developed for continuous and non-invasive monitoring of brain function by measuring blood oxygen concentration. Recent advancements in brain–computer interfacing allow us to control the neuron function of the brain by combining it with fNIRS to regulate cognitive function. In this review manuscript, we provide information regarding current advancement in fNIRS and how it provides advantages in developing brain–computer interfacing to enable neuron function. We also briefly discuss about how we can use this technology for further applications.
- Published
- 2021
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26. Alzheimer’s Disease: A Molecular View of β-Amyloid Induced Morbific Events
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Rajmohamed Mohamed Asik, Natarajan Suganthy, Mohamed Asik Aarifa, Arvind Kumar, Krisztián Szigeti, Domokos Mathe, Balázs Gulyás, Govindaraju Archunan, and Parasuraman Padmanabhan
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amyloid beta ,Alzheimer’s disease ,inflammation ,gene regulation ,organelle dysfunction ,Biology (General) ,QH301-705.5 - Abstract
Amyloid-β (Aβ) is a dynamic peptide of Alzheimer’s disease (AD) which accelerates the disease progression. At the cell membrane and cell compartments, the amyloid precursor protein (APP) undergoes amyloidogenic cleavage by β- and γ-secretases and engenders the Aβ. In addition, externally produced Aβ gets inside the cells by receptors mediated internalization. An elevated amount of Aβ yields spontaneous aggregation which causes organelles impairment. Aβ stimulates the hyperphosphorylation of tau protein via acceleration by several kinases. Aβ travels to the mitochondria and interacts with its functional complexes, which impairs the mitochondrial function leading to the activation of apoptotic signaling cascade. Aβ disrupts the Ca2+ and protein homeostasis of the endoplasmic reticulum (ER) and Golgi complex (GC) that promotes the organelle stress and inhibits its stress recovery machinery such as unfolded protein response (UPR) and ER-associated degradation (ERAD). At lysosome, Aβ precedes autophagy dysfunction upon interacting with autophagy molecules. Interestingly, Aβ act as a transcription regulator as well as inhibits telomerase activity. Both Aβ and p-tau interaction with neuronal and glial receptors elevate the inflammatory molecules and persuade inflammation. Here, we have expounded the Aβ mediated events in the cells and its cosmopolitan role on neurodegeneration, and the current clinical status of anti-amyloid therapy.
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- 2021
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27. An Overview on Cognitive Function Enhancement through Physical Exercises
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Narayanasamy Sai Srinivas, Vijayaragavan Vimalan, Parasuraman Padmanabhan, and Balázs Gulyás
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cognitive function ,physical activity ,exercise ,imaging modalities ,fMRI ,fNIRS ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
This review is extensively focused on the enhancement of cognitive functions while performing physical exercises categorized into cardiovascular exercises, resistance training, martial arts, racquet sports, dancing and mind-body exercises. Imaging modalities, viz. functional magnetic resonance imaging (fMRI), functional near-infrared spectroscopy (fNIRS) and electroencephalography (EEG), have been included in this review. This review indicates that differences are present in cognitive functioning while changing the type of physical activity performed. This study concludes that employing fNIRS helps overcome certain limitations of fMRI. Further, the effects of physical activity on a diverse variety of the population, from active children to the old people, are discussed.
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- 2021
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28. Nanotechnology Facilitated Cultured Neuronal Network and Its Applications
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Satnam Singh, Sachin Mishra, Song Juha, Manojit Pramanik, Parasuraman Padmanabhan, and Balázs Gulyás
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nanotechnology ,neuronal network ,neural stem cells ,nanopatterning ,nanoelectrode ,neuronal signal recording ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
The development of a biomimetic neuronal network from neural cells is a big challenge for researchers. Recent advances in nanotechnology, on the other hand, have enabled unprecedented tools and techniques for guiding and directing neural stem cell proliferation and differentiation in vitro to construct an in vivo-like neuronal network. Nanotechnology allows control over neural stem cells by means of scaffolds that guide neurons to reform synaptic networks in suitable directions in 3D architecture, surface modification/nanopatterning to decide cell fate and stimulate/record signals from neurons to find out the relationships between neuronal circuit connectivity and their pathophysiological functions. Overall, nanotechnology-mediated methods facilitate precise physiochemical controls essential to develop tools appropriate for applications in neuroscience. This review emphasizes the newest applications of nanotechnology for examining central nervous system (CNS) roles and, therefore, provides an insight into how these technologies can be tested in vitro before being used in preclinical and clinical research and their potential role in regenerative medicine and tissue engineering.
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- 2021
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29. Functional mapping of the brain for brain–computer interfacing: a review
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Satya P. Singh, Sachin Mishra, Sukrit Gupta, Parasuraman Padmanabhan, Lu Jia, Teo Kok Ann Colin, Yeo Tseng Tsai, Teo Kejia, Pramod Sankarapillai, Anand Mohan, Balázs Gulyás, School of Computer Science and Engineering, Lee Kong Chian School of Medicine (LKCMedicine), and Cognitive Neuroimaging Centre
- Subjects
Computer Networks and Communications ,Hardware and Architecture ,Control and Systems Engineering ,Brain–Computer Interfacing ,Signal Processing ,Computer science and engineering [Engineering] ,Neuroimaging ,Electrical and Electronic Engineering - Abstract
Brain–computer interfacing has been applied in a range of domains including rehabilitation, neuro-prosthetics, and neurofeedback. Neuroimaging techniques provide insight into the structural and functional aspects of the brain. There is a need to identify, map and understand the various structural areas of the brain together with their functionally active roles for the accurate and efficient design of a brain–computer interface. In this review, the functionally active areas of the brain are reviewed by analyzing the research available in the literature on brain–computer interfacing in conjunction with neuroimaging experiments. This review first provides an overview of various approaches of brain–computer interfacing and basic components in the BCI system and then discuss active functional areas of the brain being utilized in non-invasive brain–computer interfacing performed with hemodynamic signals and electrophysiological recording-based signals. This paper also discusses various challenges and limitations in BCI becoming accessible to a novice user, including security issues in the BCI system, effective ways to overcome those issues, and design implementations. Ministry of Defence (MINDEF) Nanyang Technological University Published version The authors acknowledge the support from Lee Kong Chian School of Medicine and MINDEF (NTU Project number: 04IDS001128A630). PP and BG also acknowledge the support from the Cognitive Neuro Imaging Centre (CONIC) at NTU, Singapore.
- Published
- 2023
30. Neurophysiological Correlates of Cognition as Revealed by Virtual Reality: Delving the Brain with a Synergistic Approach
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Sachin Mishra, Ajay Kumar, Parasuraman Padmanabhan, and Balázs Gulyás
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virtual reality ,neuroimaging ,neuromodulation ,perception ,stimulation ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
The synergy of perceptual psychology, technology, and neuroscience can be used to comprehend how virtual reality affects cognition of human brain. Numerous studies have used neuroimaging modalities to assess the cognitive state and response of the brain with various external stimulations. The virtual reality-based devices are well known to incur visual, auditory, and haptic induced perceptions. Neurophysiological recordings together with virtual stimulations can assist in correlating humans’ physiological perception with response in the environment designed virtually. The effective combination of these two has been utilized to study human behavior, spatial navigation performance, and spatial presence, to name a few. Moreover, virtual reality-based devices can be evaluated for the neurophysiological correlates of cognition through neurophysiological recordings. Challenges exist in the integration of real-time neuronal signals with virtual reality-based devices, and enhancing the experience together with real-time feedback and control through neuronal signals. This article provides an overview of neurophysiological correlates of cognition as revealed by virtual reality experience, together with a description of perception and virtual reality-based neuromodulation, various applications, and existing challenges in this field of research.
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- 2021
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31. An In Vivo Study of a Rat Fluid-Percussion-Induced Traumatic Brain Injury Model with [11C]PBR28 and [18F]flumazenil PET Imaging
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Krishna Kanta Ghosh, Parasuraman Padmanabhan, Chang-Tong Yang, Zhimin Wang, Mathangi Palanivel, Kian Chye Ng, Jia Lu, Jan Carlstedt-Duke, Christer Halldin, and Balázs Gulyás
- Subjects
traumatic brain injury (TBI) ,lateral fluid percussion (LFP) ,positron emission tomography (PET) ,neuroinflammation ,GABAA-benzodiazepine receptor ,PET radioligand ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
Traumatic brain injury (TBI) modelled by lateral fluid percussion-induction (LFPI) in rats is a widely used experimental rodent model to explore and understand the underlying cellular and molecular alterations in the brain caused by TBI in humans. Current improvements in imaging with positron emission tomography (PET) have made it possible to map certain features of TBI-induced cellular and molecular changes equally in humans and animals. The PET imaging technique is an apt supplement to nanotheranostic-based treatment alternatives that are emerging to tackle TBI. The present study aims to investigate whether the two radioligands, [11C]PBR28 and [18F]flumazenil, are able to accurately quantify in vivo molecular-cellular changes in a rodent TBI-model for two different biochemical targets of the processes. In addition, it serves to observe any palpable variations associated with primary and secondary injury sites, and in the affected versus the contralateral hemispheres. As [11C]PBR28 is a radioligand of the 18 kD translocator protein, the up-regulation of which is coupled to the level of neuroinflammation in the brain, and [18F]flumazenil is a radioligand for GABAA-benzodiazepine receptors, whose level mirrors interneuronal activity and eventually cell death, the use of the two radioligands may reveal two critical features of TBI. An up-regulation in the [11C]PBR28 uptake triggered by the LFP in the injured (right) hemisphere was noted on day 14, while the uptake of [18F]flumazenil was down-regulated on day 14. When comparing the left (contralateral) and right (LFPI) hemispheres, the differences between the two in neuroinflammation were obvious. Our results demonstrate a potential way to measure the molecular alterations in a rodent-based TBI model using PET imaging with [11C]PBR28 and [18F]flumazenil. These radioligands are promising options that can be eventually used in exploring the complex in vivo pharmacokinetics and delivery mechanisms of nanoparticles in TBI treatment.
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- 2021
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32. Amyloid Beta42 (Aβ42) Peptide Functionalized Iron Oxide Nanoparticles for Specific Targeting of SH-SY5Y Neuroblastoma Cells
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Yang Xia, Parasuraman Padmanabhan, Vadakke Matham Murukeshan, Balázs Gulyás, and Vimalan Vijayaragavan
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Materials science ,Amyloid ,Amyloid beta ,Biomedical Engineering ,Nanoprobe ,Bioengineering ,Peptide ,02 engineering and technology ,030218 nuclear medicine & medical imaging ,Neuroblastoma ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Alzheimer Disease ,Cell Line, Tumor ,Extracellular ,Humans ,General Materials Science ,chemistry.chemical_classification ,Amyloid beta-Peptides ,biology ,General Chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,Peptide Fragments ,Cell biology ,chemistry ,Cell culture ,biology.protein ,Magnetic Iron Oxide Nanoparticles ,0210 nano-technology ,Iron oxide nanoparticles ,Intracellular - Abstract
One of the most severe diseases threatening the ageing population is Alzheimer’s disease (AD). Recent studies found that the cellular uptake of extracellular amyloid beta (Aβ) peptides can lead to a build-up of intracellular Aβ in certain neuronal cells, which consequently lead to the onset of AD pathogenesis. It is therefore hypothesized that the detection of cells that are involved in such Aβ uptake could facilitate the early diagnosis of AD. In this work, a magnetofluorescent nanoprobe was prepared conjugating dye-labeled Aβ42 peptides with iron oxide nanoparticles (IONPs). When incubated with SH-SY5Y cells, the cellular uptake of Aβ42-IONPs was enhanced, compared to that of bare IONPs. Further, by labelling SH-SY5Y and HCT-116 cells, it was found that the Aβ42-IONPs are selectively targeting the neuronal cells. This enhanced and specific neuronal targeting is attributed to the cellular uptake of extracellular amyloid by SH-SY5Y cells. In addition, the MR relaxivities of the Aβ42-IONPs are preserved after the peptides functionalization. The results suggest that the Aβ42 functionalized magnetofluorescent IONPs can be used as a bimodal probe to interrogate the cellular uptake of amyloid peptides.
- Published
- 2021
33. Medical Image Compression Using a Radial Basic Function Neural Network
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L.R. Jonisha Miriam, A. Lenin Fred, S.N. Kumar, H. Ajay Kumar, Parasuraman Padmanabhan, Balàzs Gulyàs, and I. Christina Jane
- Published
- 2022
34. 3D Deep Learning on Medical Images: A Review
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Satya P. Singh, Lipo Wang, Sukrit Gupta, Haveesh Goli, Parasuraman Padmanabhan, and Balázs Gulyás
- Subjects
3D convolutional neural networks ,3D medical images ,classification ,segmentation ,detection ,localization ,Chemical technology ,TP1-1185 - Abstract
The rapid advancements in machine learning, graphics processing technologies and the availability of medical imaging data have led to a rapid increase in the use of deep learning models in the medical domain. This was exacerbated by the rapid advancements in convolutional neural network (CNN) based architectures, which were adopted by the medical imaging community to assist clinicians in disease diagnosis. Since the grand success of AlexNet in 2012, CNNs have been increasingly used in medical image analysis to improve the efficiency of human clinicians. In recent years, three-dimensional (3D) CNNs have been employed for the analysis of medical images. In this paper, we trace the history of how the 3D CNN was developed from its machine learning roots, we provide a brief mathematical description of 3D CNN and provide the preprocessing steps required for medical images before feeding them to 3D CNNs. We review the significant research in the field of 3D medical imaging analysis using 3D CNNs (and its variants) in different medical areas such as classification, segmentation, detection and localization. We conclude by discussing the challenges associated with the use of 3D CNNs in the medical imaging domain (and the use of deep learning models in general) and possible future trends in the field.
- Published
- 2020
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35. Fluorescent, Prussian Blue-Based Biocompatible Nanoparticle System for Multimodal Imaging Contrast
- Author
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László Forgách, Nikolett Hegedűs, Ildikó Horváth, Bálint Kiss, Noémi Kovács, Zoltán Varga, Géza Jakab, Tibor Kovács, Parasuraman Padmanabhan, Krisztián Szigeti, and Domokos Máthé
- Subjects
Prussian blue nanoparticles ,fluorescent imaging ,optical imaging ,biocompatible ,Chemistry ,QD1-999 - Abstract
(1) Background. The main goal of this work was to develop a fluorescent dye-labelling technique for our previously described nanosized platform, citrate-coated Prussian blue (PB) nanoparticles (PBNPs). In addition, characteristics and stability of the PB nanoparticles labelled with fluorescent dyes were determined. (2) Methods. We adsorbed the fluorescent dyes Eosin Y and Rhodamine B and methylene blue (MB) to PB-nanoparticle systems. The physicochemical properties of these fluorescent dye-labeled PBNPs (iron(II);iron(III);octadecacyanide) were determined using atomic force microscopy, dynamic light scattering, zeta potential measurements, scanning- and transmission electron microscopy, X-ray diffraction, and Fourier-transformation infrared spectroscopy. A methylene-blue (MB) labelled, polyethylene-glycol stabilized PBNP platform was selected for further assessment of in vivo distribution and fluorescent imaging after intravenous administration in mice. (3) Results. The MB-labelled particles emitted a strong fluorescent signal at 662 nm. We found that the fluorescent light emission and steric stabilization made this PBNP-MB particle platform applicable for in vivo optical imaging. (4) Conclusion. We successfully produced a fluorescent and stable, Prussian blue-based nanosystem. The particles can be used as a platform for imaging contrast enhancement. In vivo stability and biodistribution studies revealed new aspects of the use of PBNPs.
- Published
- 2020
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36. Applications of Image Processing in Teleradiology for the Medical Data Analysis and Transfer Based on IOT
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Kumar H. Ajay, S. N. Kumar, A. Lenin Fred, L. R. Jonisha Miriam, Balázs Gulyás, and Parasuraman Padmanabhan
- Subjects
Computer science ,business.industry ,Transfer (computing) ,Real-time computing ,Image processing ,Teleradiology ,Internet of Things ,business - Published
- 2021
37. Shallow 3D CNN for Detecting Acute Brain Hemorrhage From Medical Imaging Sensors
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Balázs Gulyás, Lipo Wang, Parasuraman Padmanabhan, Satya P. Singh, Sukrit Gupta, Lee Kong Chian School of Medicine (LKCMedicine), School of Electrical and Electronic Engineering, School of Computer Science and Engineering, and Cognitive Neuroimaging Centre
- Subjects
medicine.medical_specialty ,Subarachnoid hemorrhage ,business.industry ,3D Convolutional Neural Networks ,010401 analytical chemistry ,medicine.disease ,01 natural sciences ,Convolutional neural network ,0104 chemical sciences ,Intraventricular hemorrhage ,Binary classification ,Region of interest ,medicine ,Medical imaging ,Medicine [Science] ,Radiology ,Electrical and Electronic Engineering ,F1 score ,business ,Medical Image Sensors ,Instrumentation ,Intraparenchymal hemorrhage - Abstract
Successive layers in convolutional neural networks (CNN) extract different features from input images. Applications of CNNs to detect abnormalities in the 2D images or 3D volumes of body organs have recently become popular. However, computer-aided detection of diseases using deep CNN is challenging due to the absence of a large set of training medical images/scans and the relatively small and hard to detect abnormalities. In this paper, we propose a method for normalizing 3D volumetric scans using the intensity profile of the training samples. This aids the CNN by creating a higher contrast around the abnormal region of interest in the scan. We use the CQ500 head CT dataset to demonstrate the validity of our method for detecting different acute brain hemorrhages such as subarachnoid hemorrhage (SAH), intraparenchymal hemorrhage (IPH), subdural hematoma (SDH), and intraventricular hemorrhage (IVH). We compare the proposed method with a baseline, two variants of the 3D VGGNet architectures, Resnet, and show that the proposed method achieves significant improvement in classification performance. For binary classification, we achieved the best F1 score of 0.96 (normal vs SAH), 0.93 (normal vs IPH), 0.98 (normal vs SDH), and 0.99 (normal vs IVH), and for four-class classification, we obtained an average F1 score of 0.77. Finally, we show a limitation of the proposed method while detecting varied abnormalities. The proposed method has applications for abnormality detection for different organs. Nanyang Technological University This work was supported by the Lee Kong Chian School of Medicine and Data Science and AI Research (DSAIR) Centre of Nanyang Technological University Singapore (Project Number ADH-11/2017-DSAIR). The work of Parasuraman Padmanabhan and Balázs Gulyás was supported by the Cognitive NeuroImaging Centre (CONIC) at Nanyang Technological University Singapore.
- Published
- 2021
38. Implicit satiety goals and food-related expectations predict portion size in older adults: Findings from the BAMMBE cohort
- Author
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Aimee E. Pink, Li Ling Lee, Dorrain Yanwen Low, Yifan Yang, LaiGuan Zoey Fong, Alicia Yi Hui Kang, Peijia Liu, Hyejin Kim, Yulan Wang, Parasuraman Padmanabhan, Lynne Cobiac, Balázs Gulyás, Sven Pettersson, and Bobby K. Cheon
- Subjects
Aged, 80 and over ,Nutrition and Dietetics ,Health Status ,Surveys and Questionnaires ,Humans ,Middle Aged ,Exercise ,General Psychology ,Aged - Abstract
Portion size selection is an indicator of appetite and within younger adults, is predicted by factors such as expected satiety, liking and motivations to achieve an ideal sensation of fullness (i.e., implicit satiety goals). Currently, there is limited research available on the determinants of portion size selection within older adults. Therefore, the current study aimed to examine the relationship between individual differences in implicit satiety goals, food-related expectations, and portion size selection in older adults. Free-living older adult Singaporeans (N = 115; N
- Published
- 2022
39. Trivalent rare earth elements substitution in 58S bioactive glass matrix for bone repair applications - An in vitro and in vivo study
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Likha Chandran, Arumugam Marimuthu, Ravichandran Abimanyu, Parasuraman Padmanabhan, Munusamy Thirumavalavan, and Anbalagan M. Ballamurugan
- Subjects
General Materials Science ,Condensed Matter Physics - Published
- 2023
40. Recent Advance of Biological Molecular Imaging Based on Lanthanide-Doped Upconversion-Luminescent Nanomaterials
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Yuanzeng Min, Jinming Li, Fang Liu, Parasuraman Padmanabhan, Edwin K. L. Yeow, and Bengang Xing
- Subjects
upconversion nanoparticles ,molecular imaging ,luminescent nanomaterials ,Chemistry ,QD1-999 - Abstract
Lanthanide-doped upconversion-luminescent nanoparticles (UCNPs), which can be excited by near-infrared (NIR) laser irradiation to emit multiplex light, have been proven to be very useful for in vitro and in vivo molecular imaging studies. In comparison with the conventionally used down-conversion fluorescence imaging strategies, the NIR light excited luminescence of UCNPs displays high photostability, low cytotoxicity, little background auto-fluorescence, which allows for deep tissue penetration, making them attractive as contrast agents for biomedical imaging applications. In this review, we will mainly focus on the latest development of a new type of lanthanide-doped UCNP material and its main applications for in vitro and in vivo molecular imaging and we will also discuss the challenges and future perspectives.
- Published
- 2014
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41. Fluorescence Resonance Energy Transfer (FRET)-Based ThT Free Sensing of Beta-Amyloid Fibrillation by Carbon Dot-Ag Composites
- Author
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Balázs Gulyás, Radhika V. Nair, Parasuraman Padmanabhan, Murukeshan Vadakke Matham, School of Mechanical and Aerospace Engineering, Lee Kong Chian School of Medicine (LKCMedicine), and Centre for Optical and Laser Engineering
- Subjects
Amyloid ,Biophysics ,Nanoparticle ,chemistry.chemical_element ,02 engineering and technology ,Fibril ,01 natural sciences ,Biochemistry ,010309 optics ,Colloid ,chemistry.chemical_compound ,0103 physical sciences ,medicine ,Alzheimer’s Disease ,Physics::Optics and light [Science] ,Fibrillation ,Chemistry ,021001 nanoscience & nanotechnology ,Förster resonance energy transfer ,Plasmonics ,Thioflavin ,medicine.symptom ,0210 nano-technology ,Carbon ,Biotechnology - Abstract
Amyloid-beta proteins that form cytotoxic aggregates called amyloid-β derived diffusible ligands are responsible for various neurodegenerative diseases like Alzheimer’s and Parkinson’s disease. Novel methods for the early detection of such aggregates and inhibition of further fibrillation are highly important and need in the current situation. In this paper, we present a novel method based on fluorescence resonance energy transfer (FRET) between carbon dots and Ag nanoparticle for sensing various fibrillation stages of beta-amyloid proteins. The addition of Ag nanoparticles to carbon dot colloid is found to significantly enhance the inhibition of beta-amyloid fibrillation due to the modified hydrophobic and electrostatic interactions introduced by Ag nanoparticles and is monitored using thioflavin T (ThT) assay. Further, fluorescence quenching of carbon dots in the presence of Ag particles is found to get reduced with the increase in the incubation time of beta-amyloid fibrils. We could observe a linear trend in the variation of Stern–Volmer constants calculated based on FRET between carbon dots and Ag nanoparticles with the incubation time of beta-amyloid, indicating the potential of using the proposed FRET-based method for sensing beta-amyloid fibrillation. Economic Development Board (EDB) Ministry of Education (MOE) The authors acknowledge NTU, COLE-EDB, and Ministry of Education, MoE Singapore (RG 192/17) for financial support. B.G. and P.P. thank the support from Lee Kong Chian School of Medicine Imaging Probe Development Platform and the support from the Cognitive Neuro Imaging Centre (CONIC) at NTU
- Published
- 2021
42. Doxorubicin-Conjugated Platinum Theranostic Nanoparticles Induce Apoptosis via Inhibition of a Cell Survival (PI3K/AKT) Signaling Pathway in Human Breast Cancer Cells
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Mohamed Sultan Mohamed Jabir, Vinita Manimaran Nadar, Subramanian Tamil Selvan, Ponnuchamy Kumar, Balázs Gulyás, Selvambigai Manivannan, Srinivasan Pappu, Pitchan Arul Prakash, Parasuraman Padmanabhan, Rajiu Venkatesan, Puja Patel, Devan Umapathy, and Velanganni Antony Joseph Arokiyam
- Subjects
Chemistry ,Conjugated system ,Platinum nanoparticles ,medicine.disease ,Breast cancer ,Apoptosis ,Cancer cell ,polycyclic compounds ,medicine ,Cancer research ,General Materials Science ,Doxorubicin ,Protein kinase B ,PI3K/AKT/mTOR pathway ,medicine.drug - Abstract
Herein, we report facile theranostic platinum nanoparticles (PtNPs) conjugated to an anticancer drug, doxorubicin (DOX), in unraveling the inhibition of a cell survival PI3K/AKT (phosphatidylinosit...
- Published
- 2020
43. Nanotheranostic agents for neurodegenerative diseases
- Author
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Mathangi Palanivel, Ajay Kumar, Kah-Leong Lim, Balázs Gulyás, George K. Radda, Parasuraman Padmanabhan, and Domokos Máthé
- Subjects
medicine.medical_treatment ,Genetic enhancement ,Early detection ,Context (language use) ,02 engineering and technology ,Disease ,Bioinformatics ,Theranostic Nanomedicine ,General Biochemistry, Genetics and Molecular Biology ,03 medical and health sciences ,Drug Delivery Systems ,Animals ,Medicine ,030304 developmental biology ,Cell specific ,0303 health sciences ,business.industry ,Neurodegenerative Diseases ,Stem-cell therapy ,021001 nanoscience & nanotechnology ,3. Good health ,Pharmacological interventions ,Drug delivery ,Quality of Life ,Nanoparticles ,0210 nano-technology ,General Agricultural and Biological Sciences ,business - Abstract
Neurodegenerative diseases (NDDs), including Alzheimer's disease (AD) and Parkinson's disease (PD), affect the ageing population worldwide and while severely impairing the quality of life of millions, they also cause a massive economic burden to countries with progressively ageing populations. Parallel with the search for biomarkers for early detection and prediction, the pursuit for therapeutic approaches has become growingly intensive in recent years. Various prospective therapeutic approaches have been explored with an emphasis on early prevention and protection, including, but not limited to, gene therapy, stem cell therapy, immunotherapy and radiotherapy. Many pharmacological interventions have proved to be promising novel avenues, but successful applications are often hampered by the poor delivery of the therapeutics across the blood-brain-barrier (BBB). To overcome this challenge, nanoparticle (NP)-mediated drug delivery has been considered as a promising option, as NP-based drug delivery systems can be functionalized to target specific cell surface receptors and to achieve controlled and long-term release of therapeutics to the target tissue. The usefulness of NPs for loading and delivering of drugs has been extensively studied in the context of NDDs, and their biological efficacy has been demonstrated in numerous preclinical animal models. Efforts have also been made towards the development of NPs which can be used for targeting the BBB and various cell types in the brain. The main focus of this review is to briefly discuss the advantages of functionalized NPs as promising theranostic agents for the diagnosis and therapy of NDDs. We also summarize the results of diverse studies that specifically investigated the usage of different NPs for the treatment of NDDs, with a specific emphasis on AD and PD, and the associated pathophysiological changes. Finally, we offer perspectives on the existing challenges of using NPs as theranostic agents and possible futuristic approaches to improve them.
- Published
- 2020
44. The Exoproteome of
- Author
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Mahalingam, Srinivasan, Subramanian, Muthukumar, Durairaj, Rajesh, Vinod, Kumar, Rajamanickam, Rajakumar, Mohammad Abdulkader, Akbarsha, Balázs, Gulyás, Parasuraman, Padmanabhan, and Govindaraju, Archunan
- Subjects
Buffaloes ,Estrus ,Tandem Mass Spectrometry ,Staphylococcus ,Cervix Mucus ,Animals ,Female ,Chromatography, Liquid - Abstract
Bacterial extracellular proteins participate in the host cell communication by virtue of the modulation of pathogenicity, commensalism and mutualism. Studies on the microbiome of cervical mucus of the water buffalo (
- Published
- 2022
45. Choice of Embedded Processor for IoT-Based Teleradiology Applications and a Pilot Study on Need for Portable Teleradiology System in Rural Areas
- Author
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S. N. Kumar, A. Lenin Fred, H. Ajay Kumar, R. Melba Kani, Parasuraman Padmanabhan, and Balázs Gulyás
- Published
- 2022
46. Positron emission tomographic imaging in drug discovery
- Author
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Parasuraman Padmanabhan, Chang-Tong Yang, Sachin Mishra, Christer Halldin, Balázs Gulyás, Krishna Kanta Ghosh, Mathangi Palanivel, David Chee Eng Ng, Lee Kong Chian School of Medicine (LKCMedicine), and Cognitive Neuroimaging Centre
- Subjects
Drug ,medicine.medical_specialty ,Biodistribution ,media_common.quotation_subject ,Antineoplastic Agents ,Drug Development ,Drug Discovery ,medicine ,Humans ,Medical physics ,Medicine [Science] ,Radioactive Tracers ,Positron emission tomographic imaging ,media_common ,Pharmacology ,medicine.diagnostic_test ,business.industry ,Drug discovery ,Cardiovascular Agents ,Pet imaging ,Functional imaging ,Drug development ,Pharmacodynamics ,Positron emission tomography ,Positron-Emission Tomography ,Drug Monitoring ,Radiopharmaceuticals ,business - Abstract
Positron emission tomography (PET) is an extensively used nuclear functional imaging technique, especially for central nervous system (CNS) and oncological disorders. Currently, drug development is a lengthy and costly pursuit. Imaging with PET radiotracers could be an effective way to hasten drug discovery and advancement, because it facilitates the monitoring of key facets, such as receptor occupancy quantification, drug biodistribution, pharmacokinetic (PK) analyses, validation of target engagement, treatment monitoring, and measurement of neurotransmitter concentrations. These parameters demand careful analyses for the robust appraisal of newly formulated drugs during preclinical and clinical trials. In this review, we discuss the usage of PET imaging in radiopharmaceutical development; drug development approaches with PET imaging; and PET developments in oncological and cardiac drug discovery. Nanyang Technological University Authors acknowledge support from Lee Kong Chian School of Medicine, NTU Austrian Institute of Technology and Medical University of Vienna internal grant (NAM/15006), the LKC Medicine Imaging Probe Development Platform, Singapore, and the Cognitive Neuroimaging Centre (CONIC) at Nanyang Technological University, Singapore.
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- 2022
47. Improved crow search algorithm based on arithmetic crossover—a novel metaheuristic technique for solving engineering optimization problems
- Author
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S.N. Kumar, A. Lenin Fred, L. R. Jonisha Miriam, Parasuraman Padmanabhan, Balázs Gulyás, Ajay Kumar H, and Nisha Dayana
- Published
- 2022
48. A Voyage on Biomedical Applications of Multicomponent Nanoparticles in Medical Imaging
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A. Lenin Fred, S. N. Kumar, L. R. Jonisha Miriam, H. Ajay Kumar, Christina Jane, Parasuraman Padmanabhan, and Balázs Gulyás
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- 2022
49. Contributors
- Author
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Prachi Agrawal, Rangel Arthur, E. Aslanzadeh, A. Baghernejad, Emilio Bertolotti, Alberto Borghetti, João P.S. Catalão, Nisha Dayana, A. Lenin Fred, Reinaldo Padilha França, Amir H. Gandomi, Talari Ganesh, Shafieh Ghafori, Farhad Soleimanian Gharehchopogh, Amineh Ghazi, Balázs Gulyás, Ajay Kumar H, Ali Habibollahzade, Said Ali Hassan, Alireza Heidari, Yuzo Iano, Mohammad Sadegh Javadi, Esmaeil Keshavarz, S.N. Kumar, Farhad Hosseinzadeh Lotfi, Emmanuel Kwasi Mensah, L.R. Jonisha Miriam, Ali Wagdy Mohamed, Ana Carolina Borges Monteiro, A.F. Nematollahi, Ali Esmaeel Nezhad, Parasuraman Padmanabhan, Iman Rahimi, A. Rahiminejad, Abolfazl Ranjbar, Morteza Taherkhani, Babak Talatahari, Siamak Talatahari, Mehdi Toloo, Mohammad Tolouei, and B. Vahidi
- Published
- 2022
50. The Potential of Cognitive Neuroimaging: A Way Forward to the Mind-Machine Interface.
- Author
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Ganesh Pandarinathan, Sachin Mishra, Anu Maashaa Nedumaran, Parasuraman Padmanabhan, and Balázs Gulyás
- Published
- 2018
- Full Text
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