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Dhar A, Gupta SL, Saini P, Sinha K, Khandelwal A, Tyagi R, Singh A, Sharma P, Jaiswal RK. Nanotechnology-based theranostic and prophylactic approaches against SARS-CoV-2. Immunol Res 2024; 72:14-33. [PMID: 37682455 DOI: 10.1007/s12026-023-09416-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2023] [Accepted: 08/15/2023] [Indexed: 09/09/2023]
Abstract
SARS-CoV-2 (COVID-19) pandemic has been an unpredicted burden on global healthcare system by infecting over 700 million individuals, with approximately 6 million deaths worldwide. COVID-19 significantly impacted all sectors, but it very adversely affected the healthcare system. These effects were much more evident in the resource limited part of the world. Individuals with acute conditions were also severely impacted. Although classical COVID-19 diagnostics such as RT-PCR and rapid antibody testing have played a crucial role in reducing the spread of infection, these diagnostic techniques are associated with certain limitations. For instance, drawback of RT-PCR diagnostics is that due to degradation of viral RNA during shipping, it can give false negative results. Also, rapid antibody testing majorly depends on the phase of infection and cannot be performed on immune compromised individuals. These limitations in current diagnostic tools require the development of nanodiagnostic tools for early detection of COVID-19 infection. Therefore, the SARS-CoV-2 outbreak has necessitated the development of specific, responsive, accurate, rapid, low-cost, and simple-to-use diagnostic tools at point of care. In recent years, early detection has been a challenge for several health diseases that require prompt attention and treatment. Disease identification at an early stage, increased imaging of inner health issues, and ease of diagnostic processes have all been established using a new discipline of laboratory medicine called nanodiagnostics, even before symptoms have appeared. Nanodiagnostics refers to the application of nanoparticles (material with size equal to or less than 100 nm) for medical diagnostic purposes. The special property of nanomaterials compared to their macroscopic counterparts is a lesser signal loss and an enhanced electromagnetic field. Nanosize of the detection material also enhances its sensitivity and increases the signal to noise ratio. Microchips, nanorobots, biosensors, nanoidentification of single-celled structures, and microelectromechanical systems are some of the most modern nanodiagnostics technologies now in development. Here, we have highlighted the important roles of nanotechnology in healthcare sector, with a detailed focus on the management of the COVID-19 pandemic. We outline the different types of nanotechnology-based diagnostic devices for SARS-CoV-2 and the possible applications of nanomaterials in COVID-19 treatment. We also discuss the utility of nanomaterials in formulating preventive strategies against SARS-CoV-2 including their use in manufacture of protective equipment, formulation of vaccines, and strategies for directly hindering viral infection. We further discuss the factors hindering the large-scale accessibility of nanotechnology-based healthcare applications and suggestions for overcoming them.
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Tyagi R, Basu S, Dhar A, Gupta S, Gupta SL, Jaiswal RK. Role of Immunoglobulin A in COVID-19 and Influenza Infections. Vaccines (Basel) 2023; 11:1647. [PMID: 38005979 PMCID: PMC10675305 DOI: 10.3390/vaccines11111647] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Revised: 10/24/2023] [Accepted: 10/24/2023] [Indexed: 11/26/2023] Open
Abstract
Immunoglobulin A (IgA) is critical in the immune response against respiratory infections like COVID-19 and influenza [...].
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Lamidi S, Coe PO, Bordeianou LG, Hart AL, Hind D, Lindsay JO, Lobo AJ, Myrelid P, Raine T, Sebastian S, Fearnhead NS, Lee MJ, Adams K, Almer S, Ananthakrishnan A, Bethune RM, Block M, Brown SR, Cirocco WC, Cooney R, Davies RJ, Atici SD, Dhar A, Din S, Drobne D, Espin‐Basany E, Evans JP, Fleshner PR, Folkesson J, Fraser A, Graf W, Hahnloser D, Hager J, Hancock L, Hanzel J, Hargest R, Hedin CRH, Hill J, Ihle C, Jongen J, Kader R, Karmiris K, Katsanos KH, Keller DS, Kopylov U, Koutrabakis IE, Lamb CA, Landerholm K, Lee GC, Litta F, Limdi JK, Lopes EW, Madoff RD, Martin ST, Martin‐Perez B, Michalopoulos G, Millan M, Münch A, Nakov R, Noor NM, Oresland T, Paquette IM, Pellino G, Perra T, Porcu A, Roslani AC, Samaan MA, Sebepos‐Rogers GM, Segal JP, de Silva SD, Söderholm AM, Spinelli A, Speight RA, Steinhagen RM, Stenström P, Tsimogiannis KE, Varma MG, Verma AM, Verstockt B, Warden C, Yassin NA, Zawadzki A, Carr P, Devlin B, Avery MSP, Gecse KB, Goren I, Hellström PM, Kotze PG, McWhirter D, Naik AS, Sammour T, Selinger CP, Stein SL, Torres J, Wexner SD, Younge LC. Development of a core descriptor set for Crohn's anal fistula. Colorectal Dis 2022; 25:695-706. [PMID: 36461766 DOI: 10.1111/codi.16440] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Revised: 09/21/2022] [Accepted: 11/08/2022] [Indexed: 12/04/2022]
Abstract
AIM Crohn's anal fistula (CAF) is a complex condition, with no agreement on which patient characteristics should be routinely reported in studies. The aim of this study was to develop a core descriptor set of key patient characteristics for reporting in all CAF research. METHOD Candidate descriptors were generated from published literature and stakeholder suggestions. Colorectal surgeons, gastroenterologists and specialist nurses in inflammatory bowel disease took part in three rounds of an international modified Delphi process using nine-point Likert scales to rank the importance of descriptors. Feedback was provided between rounds to allow refinement of the next ratings. Patterns in descriptor voting were assessed using principal component analysis (PCA). Resulting PCA groups were used to organize items in rounds two and three. Consensus descriptors were submitted to a patient panel for feedback. Items meeting predetermined thresholds were included in the final set and ratified at the consensus meeting. RESULTS One hundred and thirty three respondents from 22 countries completed round one, of whom 67.0% completed round three. Ninety seven descriptors were rated across three rounds in 11 PCA-based groups. Forty descriptors were shortlisted. The consensus meeting ratified a core descriptor set of 37 descriptors within six domains: fistula anatomy, current disease activity and phenotype, risk factors, medical interventions for CAF, surgical interventions for CAF, and patient symptoms and impact on quality of life. CONCLUSION The core descriptor set proposed for all future CAF research reflects characteristics important to gastroenterologists and surgeons. This might aid transparent reporting in future studies.
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Rahman MFA, Reddy PH, Paul MC, Das S, Dhar A, Baharom MF, Latiff AA, Rusdi MFM, Wang P, Dimyati K, Harun SW. Titanium dioxide fiber saturable absorber for Q-switched fiber laser generation in the 1-micrometer region: publisher's note. APPLIED OPTICS 2022; 61:10228. [PMID: 36606785 DOI: 10.1364/ao.481299] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Indexed: 06/17/2023]
Abstract
This publisher's note serves to correct an error in Appl. Opt. 58, 3495 (2019)APOPAI0003-693510.1364/AO.58.003495.
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Rauthan A, Prabhash K, Rohatgi N, Thirumalairaj R, Agarwal A, P S, Limaye S, Batra U, Raizada N, Patil P, Dattatreya Palanki S, Sirohi B, Dhar A, Mukherjee A, Joshi N, Olsen S. 267P Genomic landscape of non-small cell lung cancer (NSCLC) in India using circulating tumor DNA (ctDNA) in clinical practice. Ann Oncol 2022. [DOI: 10.1016/j.annonc.2022.10.295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/07/2022] Open
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Mao L, Dhar A, Meng G, Fuss I, Montgomery-Recht K, Yang Z, Xu Q, Kitani A, Strober W. Blau syndrome NOD2 mutations result in loss of NOD2 cross-regulatory function. Front Immunol 2022; 13:988862. [PMID: 36189261 PMCID: PMC9520668 DOI: 10.3389/fimmu.2022.988862] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Accepted: 08/29/2022] [Indexed: 12/02/2022] Open
Abstract
The studies described here provide an analysis of the pathogenesis of Blau syndrome and thereby the function of NOD2 as seen through the lens of its dysfunction resulting from Blau-associated NOD2 mutations in its nucleotide-binding domain (NBD). As such, this analysis also sheds light on the role of NOD2 risk polymorphisms in the LRR domain occurring in Crohn’s disease. The main finding was that Blau NOD2 mutations precipitate a loss of canonical NOD2 signaling via RIPK2 and that this loss has two consequences: first, it results in defective NOD2 ligand (MDP)-mediated NF-κB activation and second, it disrupts NOD2-mediated cross-regulation whereby NOD2 downregulates concomitant innate (TLR) responses. Strong evidence is also presented favoring the view that NOD2-mediated cross-regulation is under mechanistic control by IRF4 and that failure to up-regulate this factor because of faulty NOD2 signaling is the proximal cause of defective cross-regulation and the latter’s effect on Blau syndrome inflammation. Overall, these studies highlight the role of NOD2 as a regulatory factor and thus provide additional insight into its function in inflammatory disease. Mutations in the nucleotide binding domain of the CARD15 (NOD2) gene underlie the granulomatous inflammation characterizing Blau syndrome (BS). In studies probing the mechanism of this inflammation we show here that NOD2 plasmids expressing various Blau mutations in HEK293 cells result in reduced NOD2 activation of RIPK2 and correspondingly reduced NOD2 activation of NF-κB. These in vitro studies of NOD2 signaling were accompanied by in vivo studies showing that BS-NOD2 also exhibit defects in cross-regulation of innate responses underlying inflammation. Thus, whereas over-expressed intact NOD2 suppresses TNBS-colitis, over-expressed BS-NOD2 does not; in addition, whereas administration of NOD2 ligand (muramyl dipeptide, MDP) suppresses DSS-colitis in Wild Type (WT) mice it fails to do so in homozygous or heterozygous mice bearing a NOD2 Blau mutation. Similarly, mice bearing a Blau mutation exhibit enhanced anti-collagen antibody-induced arthritis. The basis of such cross-regulatory failure was revealed in studies showing that MDP-stimulated cells bearing BS-NOD2 exhibit a reduced capacity to signal via RIPK2 as well as a reduced capacity to up-regulate IRF4, a factor shown previously to mediate NOD2 suppression of NF-κB activation. Indeed, TLR-stimulated cells bearing a Blau mutation exhibited enhanced in vitro cytokine responses that are quieted by lentivirus transduction of IRF4. In addition, enhanced anti-collagen-induced joint inflammation in mice bearing a Blau mutation was accompanied by reduced IRF4 expression in inflamed joint tissue and IRF4 expression was reduced in MDP-stimulated cells from BS patients. Thus, inflammation characterizing Blau syndrome are caused, at least in part, by faulty canonical signaling and reduce IRF4-mediated cross-regulation.
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Santra S, Kethepalli J, Agarwal S, Dhar A, Kulkarni M, Kundu A. Gap Statistics for Confined Particles with Power-Law Interactions. PHYSICAL REVIEW LETTERS 2022; 128:170603. [PMID: 35570430 DOI: 10.1103/physrevlett.128.170603] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Accepted: 03/25/2022] [Indexed: 06/15/2023]
Abstract
We consider the N particle classical Riesz gas confined in a one-dimensional external harmonic potential with power-law interaction of the form 1/r^{k}, where r is the separation between particles. As special limits it contains several systems such as Dyson's log-gas (k→0^{+}), the Calogero-Moser model (k=2), the 1D one-component plasma (k=-1), and the hard-rod gas (k→∞). Despite its growing importance, only large-N field theory and average density profile are known for general k. In this Letter, we study the fluctuations in the system by looking at the statistics of the gap between successive particles. This quantity is analogous to the well-known level-spacing statistics which is ubiquitous in several branches of physics. We show that the variance goes as N^{-b_{k}} and we find the k dependence of b_{k} via direct Monte Carlo simulations. We provide supporting arguments based on microscopic Hessian calculation and a quadratic field theory approach. We compute the gap distribution and study its system size scaling. Except in the range -1<k<0, we find scaling for all k>-2 with both Gaussian and non-Gaussian scaling forms.
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Lee YW, Chuang JY, Lin CC, Paul MC, Das S, Dhar A. High-efficiency picosecond mode-locked laser using a thulium-doped nanoengineered yttrium-alumina-silica fiber as the gain medium. OPTICS EXPRESS 2021; 29:14682-14693. [PMID: 33985185 DOI: 10.1364/oe.422947] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Accepted: 04/22/2021] [Indexed: 06/12/2023]
Abstract
We report the theoretical and experimental investigation of a self-starting mode-locked fiber laser with a nanoengineered Tm3+-doped yttrium-alumina-silica (YAS) fiber as the gain medium. The YAS fiber exhibits a higher capability of Tm3+ cluster elimination than commercial silica fibers. The Tm3+ fluorescence properties and YAS dispersion are well characterized. As a result, an efficient picosecond mode-locked fiber laser is demonstrated with a slope efficiency of 14.14% and maximum pulse energy of 1.27 nJ. To the best of our knowledge, this is the first mode-locked fiber laser based on a Tm3+-doped YAS fiber. The experimental observation is also supported by the numerical analysis.
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Chawla AS, Khalsa JK, Dhar A, Gupta S, Umar D, Arimbasseri GA, Bal V, George A, Rath S. A role for cell-autocrine interleukin-2 in regulatory T-cell homeostasis. Immunology 2020; 160:295-309. [PMID: 32187647 DOI: 10.1111/imm.13194] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2019] [Revised: 03/16/2020] [Accepted: 03/16/2020] [Indexed: 12/30/2022] Open
Abstract
Activated T-cells make both interleukin-2 (IL2) and its high-affinity receptor component CD25. Regulatory CD4 T-cells (Treg cells) do not make IL2, and the IL2-CD25 circuit is considered a paracrine circuit crucial in their generation and maintenance. Yet, all T-cells are capable of making IL2 at some stage during differentiation, making a cell-intrinsic autocrine circuit additionally possible. When we re-visited experiments with mixed bone marrow chimeras using a wide range of ratios of wild-type (WT) and IL2-/- genotype progenitors, we found that, as expected, thymic Treg cells were almost equivalent between WT and IL2-/- genotypes at ratios with WT prominence. However, at WT-limiting ratios, the IL2-/- genotype showed lower thymic Treg frequencies, indicating a role for cell-intrinsic autocrine IL2 in thymic Treg generation under IL2-limiting conditions. Further, peripheral IL2-/- naive CD4 T-cells showed poor conversion to inducible Tregs (pTregs) both in vivo and in vitro, again indicating a significant role for cell-intrinsic autocrine IL2 in their generation. Peripherally, the IL2-/- genotype was less prominent at all WT:IL2-/- ratios among both thymic Tregs (tTregs) and pTregs, adoptively transferred IL2-/- Tregs showed poorer survival than WT Tregs did, and RNA-seq analysis of WT and IL2-/- Tregs showed interesting differences in the T-cell receptor and transforming growth factor-beta-bone morphogenetic protein-JNK pathways between them, suggesting a non-titrating role for cell-intrinsic autocrine IL2 in Treg programming. These data indicate that cell-intrinsic autocrine IL2 plays significant roles in Treg generation and maintenance.
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Li W, Dhar A, Deng X, Kasamatsu K, Barbiero L, Santos L. Disorderless Quasi-localization of Polar Gases in One-Dimensional Lattices. PHYSICAL REVIEW LETTERS 2020; 124:010404. [PMID: 31976727 DOI: 10.1103/physrevlett.124.010404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Indexed: 06/10/2023]
Abstract
One-dimensional polar gases in deep optical lattices present a severely constrained dynamics due to the interplay between dipolar interactions, energy conservation, and finite bandwidth. The appearance of dynamically bound nearest-neighbor dimers enhances the role of the 1/r^{3} dipolar tail, resulting in the absence of external disorder, in quasi-localization via dimer clustering for very low densities and moderate dipole strengths. Furthermore, even weak dipoles allow for the formation of self-bound superfluid lattice droplets with a finite doping of mobile, but confined, holons. Our results, which can be extrapolated to other power-law interactions, are directly relevant for current and future lattice experiments with magnetic atoms and polar molecules.
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Dhar A, Chawla M, Chattopadhyay S, Oswal N, Umar D, Gupta S, Bal V, Rath S, George A, Arimbasseri GA, Basak S. Role of NF-kappaB2-p100 in regulatory T cell homeostasis and activation. Sci Rep 2019; 9:13867. [PMID: 31554891 PMCID: PMC6761191 DOI: 10.1038/s41598-019-50454-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Accepted: 09/10/2019] [Indexed: 12/12/2022] Open
Abstract
The immunological roles of the nuclear factor-kappaB (NF-κB) pathway are mediated via the canonical components in immune responses and via non-canonical components in immune organogenesis and homeostasis, although the two components are capable of crosstalk. Regulatory CD4 T cells (Tregs) are homeostatically functional and represent an interesting potential meeting point of these two NF-κB components. We show that mice deficient in the non-canonical NF-κB component gene Nfkb2 (p100) had normal thymic development and suppressive function of Tregs. However, they had enhanced frequencies of peripheral 'effector-phenotype' Tregs (eTregs). In bi-parental chimeras of wild-type (WT) and Nfkb2-/- mice, the Nfkb2-/- genotype was over-represented in Tregs, with a further increase in the relative prominence of eTregs. Consistent with distinct properties of eTregs, the Nfkb2-/- genotype was more prominent in Tregs in extra-lymphoid tissues such as liver in the bi-parental chimeras. The Nfkb2-/- Tregs also displayed greater survival, activation and proliferation in vivo. These Nfkb2-/- Tregs showed higher nuclear NF-κB activity mainly comprising of RelB-containing dimers, in contrast to the prominence of cRel- and RelA-containing dimers in WT Tregs. Since p100 is an inhibitor of RelB activation as well as a participant as cleaved p52 in RelB nuclear activity, we tested bi-parental chimeras of WT and Relb-/- mice, and found normal frequencies of Relb-/- Tregs and eTregs in these chimeric mice. Our findings confirm and extend recent data, and indicate that p100 normally restrains RelB-mediated Treg activation, and in the absence of p100, p50-RelB dimers can contribute to Treg activation.
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Agarwal S, Dhar A, Kulkarni M, Kundu A, Majumdar SN, Mukamel D, Schehr G. Harmonically Confined Particles with Long-Range Repulsive Interactions. PHYSICAL REVIEW LETTERS 2019; 123:100603. [PMID: 31573302 DOI: 10.1103/physrevlett.123.100603] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Indexed: 06/10/2023]
Abstract
We study an interacting system of N classical particles on a line at thermal equilibrium. The particles are confined by a harmonic trap and repel each other via pairwise interaction potential that behaves as a power law ∝∑[under i≠j][over N]|x_{i}-x_{j}|^{-k} (with k>-2) of their mutual distance. This is a generalization of the well-known cases of the one-component plasma (k=-1), Dyson's log gas (k→0^{+}), and the Calogero-Moser model (k=2). Because of the competition between harmonic confinement and pairwise repulsion, the particles spread over a finite region of space for all k>-2. We compute exactly the average density profile for large N for all k>-2 and show that while it is independent of temperature for sufficiently low temperature, it has a rich and nontrivial dependence on k with distinct behavior for -2<k<1, k>1 and k=1.
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Khalsa JK, Chawla AS, Prabhu SB, Vats M, Dhar A, Dev G, Das N, Mukherjee S, Tanwar S, Banerjee H, Durdik JM, Bal V, George A, Rath S, Arimbasseri GA. Functionally significant metabolic differences between B and T lymphocyte lineages. Immunology 2019; 158:104-120. [PMID: 31318442 DOI: 10.1111/imm.13098] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Revised: 06/13/2019] [Accepted: 07/11/2019] [Indexed: 12/16/2022] Open
Abstract
Activation of B and T lymphocytes leads to major remodelling of the metabolic landscape of the cells enabling their post-activation functions. However, naive B and T lymphocytes also show metabolic differences, and the genesis, nature and functional significance of these differences are not yet well understood. Here we show that resting B-cells appeared to have lower energy demands than resting T-cells as they consumed lower levels of glucose and fatty acids and produced less ATP. Resting B-cells are more dependent on OXPHOS, while T-cells show more dependence on aerobic glycolysis. However, despite an apparently higher energy demand, T lineage cells showed lower rates of protein synthesis than equivalent B lineage stages. These metabolic differences between the two lineages were established early during lineage differentiation, and were functionally significant. Higher levels of protein synthesis in B-cells were associated with increased synthesis of MHC class II molecules and other proteins associated with antigen internalization, transport and presentation. The combination of higher energy demand and lower protein synthesis in T-cells was consistent with their higher ATP-dependent motility. Our data provide an integrated perspective of the metabolic differences and their functional implications between the B and T lymphocyte lineages.
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Oakey J, Smith C, Underwood D, Afsharnasab M, Alday-Sanz V, Dhar A, Sivakumar S, Sahul Hameed AS, Beattie K, Crook A. Global distribution of white spot syndrome virus genotypes determined using a novel genotyping assay. Arch Virol 2019; 164:2061-2082. [PMID: 31131427 PMCID: PMC6591196 DOI: 10.1007/s00705-019-04265-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2019] [Accepted: 03/29/2019] [Indexed: 11/25/2022]
Abstract
White spot disease, caused by infection with white spot syndrome virus (WSSV), is a serious panzootic affecting prawn aquaculture. The disease has spread rapidly around the prawn-culturing regions of the world through a number of previously identified mechanisms. The ability to distinguish and trace strains of WSSV is of great benefit to identify, and then limit, the translocation routes of the disease. Here, we describe a novel genotyping method using 34 short tandem repeat regions of the viral genome concurrently. This technique is highly sensitive to strain differences when compared to previous methods. The efficacy of the described method is demonstrated by testing WSSV isolates from around the globe, showing regional genotypic differences. The differences in the genotypes were used to create a global minimum spanning network, and in most cases the observed relationships were substantiated with verification of transboundary movement. This novel panel of STR markers will provide a valuable epidemiological tool for white spot disease. We have applied this to an outbreak of the disease in Queensland, Australia, that occurred in 2016. While the results indicate that the source of this outbreak currently remains cryptic, the analyses have provided valuable insights with which to further study the origins of the strains involved.
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Rahman MFA, Reddy PH, Paul MC, Das S, Dhar A, Baharom MF, Latiff AA, Rusdi MFM, Wang P, Dimyati K, Harun SW. Titanium dioxide fiber saturable absorber for Q-switched fiber laser generation in the 1-micrometer region. APPLIED OPTICS 2019; 58:3495-3500. [PMID: 31044848 DOI: 10.1364/ao.58.003495] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Accepted: 03/24/2019] [Indexed: 06/09/2023]
Abstract
A passively Q-switched ytterbium-doped fiber laser (YDFL) operating at 1062 nm was demonstrated by using a segment of 20 cm titanium dioxide-doped fiber saturable absorber (TiO2DF SA). The Q-switched YDFL emerged stably with tunable repetition rates ranging from 32 kHz to 53 kHz as the pump power rose from 109 mW to 233 mW. Within this range of pump power, a maximum output power of 10.1 mW, maximum peak power of 75 mW, and maximum pulse energy of 191 nJ were obtained. The narrowest pulse width of 2.55 μs was attained at the maximum pump power of 233 mW, while the signal-to-noise ratio of the fundamental frequency was 47 dB. This demonstration reveals that the proposed TiO2DF SA is feasible for constructing a flexible and reliably stable Q-switched pulsed fiber laser in the 1-micrometer region.
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Sharma CK, Ranjan P, Qaiser D, Dhar A, Srivastava A, Kataria K. Abstract PD8-06: Fluorescence guided breast conserving surgery. Cancer Res 2019. [DOI: 10.1158/1538-7445.sabcs18-pd8-06] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Background. Palpation guided breast conserving surgery for breast cancer is associated with tumor involved margins in up to 41% of cases. Ultrasound guided breast conserving surgery and frozen section biopsy result in a significant reduction in margin positivity. However, intra-operative USG and Frozen section biopsy are not widely available. We aimed to find a simple and effective technique for intra-operative margin assessment during breast conserving surgery.
Hypothesis. Intravenously injected Fluorescein reaches tumor tissue in high concentration due to increased tumor blood flow and increased capillary permeability which can be detected by blue light (494 nm).
Objective. To find diagnostic accuracy of fluorescence guided identification of tumor margins during breast conserving surgery.
Methods. A total of 60 patients with T1–T2 invasive breast cancer who underwent breast conserving surgery at AIIMS, New Delhi between March, 2016 to Feb, 2018 were included. Each patient received 2 ml of intra-venous 20% Fluorescein sodium just before skin incision. Breast conserving surgery was performed under USG guidance. Specimen was bisected and examined under blue light. Fluorescent tumor margins were identified and six biopsies taken from non-fluorescent area 5mm outside from fluorescent tumor margins at 2,4,6,8,10 and 12 o'clock position. The involvement of USG guided margin was compared with Fluorescence guided margins on histopathology.
Results. Mean age of the patient was 51.2 (SD=6.4) years. Fourteen patients (20.3 %) had T1 tumors while 46 patients(69.7%) had T2 tumors. Axillary nodes were involved in 19 patients (20.1%) and all underwent axillary node dissection. Eight patients (13.3%) received NACT. Fluorescent margins in two (3.3%) out of 60 patients were involved by tumor while USG guided margins in all the 60 patients were free. The specificity of fluorescence in identifying uninvolved tumor margins during breast conserving surgery is 96.7%.
No patient developed adverse drug reactions.
Conclusion. The fluorescence identifies tumor free margins with 96.7% accuracy. It is simple, effective and affordable method of identifying margin positivity in breast conservation surgery.
Citation Format: Sharma CK, Ranjan P, Qaiser D, Dhar A, Srivastava A, Kataria K. Fluorescence guided breast conserving surgery [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr PD8-06.
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Singh K, Dhar A, Srivastava A, Ranjan P, Kataria K, Gour KS. Abstract P3-14-04: Prevention of lymphedema in patients undergoing axillary dissection for breast cancer by benzathine penicillin: A non-inferiority randomised controlled trial. Cancer Res 2019. [DOI: 10.1158/1538-7445.sabcs18-p3-14-04] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Background: Axillary lymph node dissection (ALND) is performed for axillary lymph nodal metastasis. Major complication of ALND is lymphedema. Lymphedema is a morbid condition associated with impaired activities of daily life and deterioration in quality of life (QOL). Olszewski et al (Lymphology. 2005 Jun;38(2):66–80) have shown that low-grade staphylococcal infection is a risk factor for lymphedema. Hence, we embarked upon a randomised controlled trial with non-inferiority hypothesis to evaluate efficacy of injection Benzathine penicillin in preventing breast cancer related lymphedema.
Methods: In this 2 group, open label, parallel design randomized controlled trial; patients undergoing ALND for breast cancer were included. Patients were randomized using block randomization to either injection Benzathine penicillin group or in control group. Patients in the penicillin group received injection Benzathine penicillin 1.2 million units as deep intramuscular injection after antibiotic sensitivity testing at intervals of 3 weeks. Primary endpoint was development of lymphedema at 6 months follow up. Analyses were done on an intention to treat basis. Lymphedema was defined as increase in >200ml of volume on water displacement method and or increase in arm circumference of >2cm from pre surgery values (Lancet Oncol. 2013 May 1;14(6):500–15).
Findings: Between July 2016 and December 2017, 83 ladies were randomly allocated, 40 in the penicillin group and 43 in control group. At 6 months follow up; a total of 15 (18.07%) patients had lymphedema. Out of them 5 patients were in penicillin group and 10 in the control group. Cellulitis was seen in 2/3rd of patients (10 out of 15) having lymphedema. The relative risk of cellulitis in penicillin group was 0.119 with 95% CI of (0.016-0.901) and prevented fraction of 0.881. Other factors like radiotherapy, type of surgery for primary tumor, extent of axillary dissection and type of chemotherapy were comparable in both groups. None of the patients receiving penicillin have any adverse effect or allergic reaction to the drug during the study period.
Comparison of lymphedema and cellulitis in two groupsOutcome Penicillin groupControl groupRR ( 95% CI)PFLymphedemaPresent05100.538 (0.201-1.437)0.462 Absent3533 CellulitisPresent01090.119 (0.016-0.901)0.881 Absent3934 RR: Relative risk, PF: Prevented fraction, CI: Confidence interval
Conclusion: Penicillin administration in patients undergoing axillary lymph node dissection is safe and significantly reduces risk of lymphedema and cellulitis.
Novelty: This is the first randomised trial demonstrating the benefit of long term administration of penicillin in reducing lymphedema and cellulitis.
Citation Format: Singh K, Dhar A, Srivastava A, Ranjan P, Kataria K, Gour KS. Prevention of lymphedema in patients undergoing axillary dissection for breast cancer by benzathine penicillin: A non-inferiority randomised controlled trial [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P3-14-04.
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Mustfa SA, Singh M, Suhail A, Mohapatra G, Verma S, Chakravorty D, Rana S, Rampal R, Dhar A, Saha S, Ahuja V, Srikanth CV. SUMOylation pathway alteration coupled with downregulation of SUMO E2 enzyme at mucosal epithelium modulates inflammation in inflammatory bowel disease. Open Biol 2018; 7:rsob.170024. [PMID: 28659381 PMCID: PMC5493774 DOI: 10.1098/rsob.170024] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Accepted: 05/25/2017] [Indexed: 02/06/2023] Open
Abstract
Post-translational modification pathways such as SUMOylation are integral to all cellular processes and tissue homeostasis. We investigated the possible involvement of SUMOylation in the epithelial signalling in Crohn's disease (CD) and ulcerative colitis (UC), the two major forms of inflammatory bowel disease (IBD). Initially in a murine model of IBD, induced by dextran–sulfate–sodium (DSS mice), we observed inflammation accompanied by a lowering of global SUMOylation of colonic epithelium. The observed SUMOylation alteration was due to a decrease in the sole SUMO E2 enzyme (Ubc9). Mass-spectrometric analysis revealed the existence of a distinct SUMOylome (SUMO-conjugated proteome) in DSS mice with alteration of key cellular regulators, including master kinase Akt1. Knocking-down of Ubc9 in epithelial cells resulted in dramatic activation of inflammatory gene expression, a phenomenon that acted via reduction in Akt1 and its SUMOylated form. Importantly, a strong decrease in Ubc9 and Akt1 was also seen in endoscopic biopsy samples (N = 66) of human CD and UC patients. Furthermore, patients with maximum disease indices were always accompanied by severely lowered Ubc9 or SUMOylated-Akt1. Mucosal tissues with severely compromised Ubc9 function displayed higher levels of pro-inflammatory cytokines and compromised wound-healing markers. Thus, our results reveal an important and previously undescribed role for the SUMOylation pathway involving Ubc9 and Akt1 in modulation of epithelial inflammatory signalling in IBD.
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Khoury R, Dawood S, Khoury M, Khan F, Al Khatib F, Bello M, Hamadi A, Kazim H, Dhar A, Nasioulas G. Hereditary cancer syndromes and development of tele genetics program in the Asia-Pacific, Middle East region. Ann Oncol 2018. [DOI: 10.1093/annonc/mdy441.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Dharabuoriya A, Singhal M, Srivastava A, Dhar A, Kumar C, Kataria K, Ranjan P. Lateral mammary crease incision – an aesthetic incision for Skin and Nipple sparing mastectomy. Eur J Cancer 2018. [DOI: 10.1016/s0959-8049(18)30436-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Pluard T, Oh SY, Oliveira M, Cescon D, Tan-Chiu E, Wu Y, Carpenter C, Cunningham E, Ballas M, Dhar A, Sparano J. Abstract OT3-06-07: A phase I/II dose escalation and expansion study to investigate the safety, pharmacokinetics, pharmacodynamics and clinical activity of GSK525762 in combination with fulvestrant in subjects with ER+ breast cancer. Cancer Res 2018. [DOI: 10.1158/1538-7445.sabcs17-ot3-06-07] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Background:
Advanced or metastatic ER+BC (estrogen receptor positive breast cancer) is an incurable illness that will prove fatal for most afflicted women. Current standards of care include endocrine, targeted, and chemotherapy. Preclinical data suggest that altering the expression of the estrogen receptor (ER) as well as other ER-responsive genes may provide therapeutic benefit for women for whom endocrine therapy alone has proven inadequate. The bromodomain (BRD) and extra-terminal (BET) family of proteins (BRD2, BRD3, BRD4 and BRDT) bind to acetyl-histone residues and epigenetically control transcription of genes driving cell survival and proliferation. BET proteins have been implicated in carcinogenesis and treatment resistance in multiple tumors including ER+BC, and are a novel target for therapy in breast cancer. GSK525762 is a pan-BET inhibitor that has shown strong synergistic activity with fulvestrant in killing ER+BC cells in vitro and in xenograft models. The combination of BET agents with endocrine therapy may provide therapeutic benefit and restore sensitivity to ER targeting agents like fulvestrant.
Trial Design & Specific Aims:
This study is a Phase I/II dose-escalation, expansion (Phase I) and randomized control (Phase II) study with oral administration of GSK525762 in combination with fulvestrant in advanced or metastatic ER+BC subjects, whose disease has progressed on prior treatment with at least one line of endocrine therapy.
Phase I of the study is designed as parallel single arms to determine a recommended Phase 2 dose (RP2D) based on safety, tolerability, pharmacokinetic, and efficacy profiles in two distinct populations of ER+ breast cancer:
Subjects with disease that relapsed during treatment or within 12 months of adjuvant therapy with an AI, OR disease that progressed during treatment with an AI for advanced/metastatic disease.
OR
Subjects with disease that progressed during treatment with the combination of a CDK4/6 inhibitor plus letrozole for advanced or metastatic disease.
Phase II of the study is a randomized, double-blind, placebo-controlled cohort, designed to evaluate the efficacy of the combination.
Key Eligibility Criteria: Patients must have received <3 lines of systemic anti-cancer therapy (≤1 line of chemo), measurable disease, and PS 0-1.
Statistical Methods: A modified toxicity probability interval (mTPI) design will be used to monitor safety. A Bayesian adaptive design will be used to evaluate efficacy in Phase 1.
Present and Target Accrual: Target enrolment will be ˜300 subjects across ˜50 sites worldwide. To date, 2 subjects have been enrolled.
Contact Information: Elizabeth Cunningham, Elizabeth.A.Cunningham@GSK.com.
NCT02964507
Funding: GSK
Citation Format: Pluard T, Oh SY, Oliveira M, Cescon D, Tan-Chiu E, Wu Y, Carpenter C, Cunningham E, Ballas M, Dhar A, Sparano J. A phase I/II dose escalation and expansion study to investigate the safety, pharmacokinetics, pharmacodynamics and clinical activity of GSK525762 in combination with fulvestrant in subjects with ER+ breast cancer [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr OT3-06-07.
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Mullish BH, Mathew S, Dhar A. Gastrointestinal: Duodenal variceal bleeding secondary to thrombophilia-related portal vein thrombosis. J Gastroenterol Hepatol 2018; 33:336. [PMID: 29372608 DOI: 10.1111/jgh.13982] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/09/2022]
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Tai D, Dhar A, Yusuf A, Marshall A, O'Beirne J, Patch D, Tsochatzis E, Alexander G, Portal J, Thalheimer U, Thorburn D, Kallis Y, Westbrook R. The Royal Free Hospital ‘hub-and-spoke network model’ delivers effective care and increased access to liver transplantation. Public Health 2018; 154:164-171. [DOI: 10.1016/j.puhe.2017.10.012] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2017] [Revised: 10/09/2017] [Accepted: 10/19/2017] [Indexed: 01/16/2023]
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Mukherjee T, Chatterjee B, Dhar A, Bais SS, Chawla M, Roy P, George A, Bal V, Rath S, Basak S. A TNF-p100 pathway subverts noncanonical NF-κB signaling in inflamed secondary lymphoid organs. EMBO J 2017; 36:3501-3516. [PMID: 29061763 PMCID: PMC5709727 DOI: 10.15252/embj.201796919] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Revised: 08/22/2017] [Accepted: 09/18/2017] [Indexed: 12/16/2022] Open
Abstract
Lymphotoxin-beta receptor (LTβR) present on stromal cells engages the noncanonical NF-κB pathway to mediate RelB-dependent expressions of homeostatic chemokines, which direct steady-state ingress of naïve lymphocytes to secondary lymphoid organs (SLOs). In this pathway, NIK promotes partial proteolysis of p100 into p52 that induces nuclear translocation of the RelB NF-κB heterodimers. Microbial infections often deplete homeostatic chemokines; it is thought that infection-inflicted destruction of stromal cells results in the downregulation of these chemokines. Whether inflammation per se also regulates these processes remains unclear. We show that TNF accumulated upon non-infectious immunization of mice similarly downregulates the expressions of these chemokines and consequently diminishes the ingress of naïve lymphocytes in inflamed SLOs. Mechanistically, TNF inactivated NIK in LTβR-stimulated cells and induced the synthesis of Nfkb2 mRNA encoding p100; these together potently accumulated unprocessed p100, which attenuated the RelB activity as inhibitory IκBδ. Finally, a lack of p100 alleviated these TNF-mediated inhibitions in inflamed SLOs of immunized Nfkb2-/- mice. In sum, we reveal that an inhibitory TNF-p100 pathway modulates the adaptive compartment during immune responses.
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McDonnell MJ, Punnoose S, Viswanath YKS, Wadd NJ, Dhar A. Gastrointestinal stromal tumours (GISTs): an insight into clinical practice with review of literature. Frontline Gastroenterol 2017; 8:19-25. [PMID: 28839880 PMCID: PMC5369437 DOI: 10.1136/flgastro-2015-100670] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Revised: 06/13/2016] [Accepted: 06/27/2016] [Indexed: 02/04/2023] Open
Abstract
BACKGROUND Gastrointestinal stromal tumours (GISTs) are rare mesenchymal tumours of the gastrointestinal tract. We retrospectively reviewed the clinical management of all patients with GIST presenting to a regional multidisciplinary upper gastrointestinal cancer group in the north of England. METHODS Clinical, pathological, immunohistochemical treatment strategies, follow-up and outcome data on all patients with GIST between 2007 and 2012 were reviewed. Tumours were categorised by risk according to the National Institutes of Health (NIH) and AFIP models. RESULTS 36 (85.7%) of 42 tumours were located in the stomach, 5 (11.9%) in the small intestine and 1 (2.4%) in the oesophagus. Median age of patients was 68 (range 43-91) years. 24 patients (57.1%) were female. Tumour size ranged from 1.0 to 12.7 cm with mean size of 5.46 cm. Metastasis was present in 19 (45.2%) patients at diagnosis with distant metastases in 12 patients. Liver was the most common site of metastases. Histology and immunohistochemical analysis was available in 32 (76.2%) patients. Most common histology was spindle cell morphology 17/32 (53.1%) followed by epithelioid 9/32 (28.1%) and mixed morphology 5/32 (15.6%). The positive rate for KIT protein (CD117) was 90.6%, while that for CD34 was 75.0%. 12/25 (48.0%) and 8/23 (34.8%) patients were categorised as high risk as per NIH and AFIP risk scores, respectively. 23/42 (54.8%) patients underwent surgical resection, after which 5/23 (21.7%) had adjuvant imatinib therapy. Imatinib was given as primary therapy in 14/42 (33.3%) patients. CONCLUSIONS Surgery alone may not be a curative treatment for GISTs. Targeted therapy with imatinib may play an important role in the treatment of GISTs. Further risk categorisation models may be needed to evaluate GIST behaviour and prognosis.
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