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Chakrabarti D, Rajan S, Akhtar N, Qayoom S, Gupta S, Verma M, Srivastava K, Kumar V, Bhatt MLB, Gupta R. Short-course radiotherapy with consolidation chemotherapy versus conventionally fractionated long-course chemoradiotherapy for locally advanced rectal cancer: randomized clinical trial. Br J Surg 2021; 108:511-520. [PMID: 33724296 DOI: 10.1093/bjs/znab020] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Revised: 10/14/2020] [Accepted: 12/20/2020] [Indexed: 01/08/2023]
Abstract
BACKGROUND The trial hypothesis was that, in a resource-constrained situation, short-course radiotherapy would improve treatment compliance compared with conventional chemoradiotherapy for locally advanced rectal cancer, without compromising oncological outcomes. METHODS In this open-label RCT, patients with cT3, cT4 or node-positive non-metastatic rectal cancer were allocated randomly to 5 × 5 Gy radiotherapy and two cycles of XELOX (arm A) or chemoradiotherapy with concurrent capecitabine (arm B), followed by total mesorectal excision in both arms. All patients received a further six cycles of adjuvant chemotherapy with the XELOX regimen. The primary endpoint was treatment compliance, defined as the ability to complete planned treatment, including neoadjuvant radiochemotherapy, surgery, and adjuvant chemotherapy to a dose of six cycles. RESULTS Of 162 allocated patients, 140 were eligible for analysis: 69 in arm A and 71 in arm B. Compliance with planned treatment (primary endpoint) was greater in arm A (63 versus 41 per cent; P = 0.005). The incidence of acute toxicities of neoadjuvant therapy was similar (haematological: 28 versus 32 per cent, P = 0.533; gastrointestinal: 14 versus 21 per cent, P = 0.305; grade III-IV: 2 versus 4 per cent, P = 1.000). Delays in radiotherapy were less common in arm A (9 versus 45 per cent; P < 0.001), and overall times for completion of neoadjuvant treatment were shorter (P < 0.001). The rates of R0 resection (87 versus 90 per cent; P = 0.554), sphincter preservation (32 versus 35 per cent; P = 0.708), pathological complete response (12 versus 10 per cent; P = 0.740), and overall tumour downstaging (75 versus 75 per cent; P = 0.920) were similar. Downstaging of the primary tumour (ypT) was more common in arm A (P = 0.044). There was no difference in postoperative complications between trial arms (P = 0.838). CONCLUSION Reduced treatment delays and a higher rate of compliance were observed with treatment for short-course radiotherapy with consolidation chemotherapy, with no difference in early oncological surgical outcomes. In time- and resource-constrained rectal cancer units in developing countries, short-course radiotherapy should be the standard of care.
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Ojha V, Verma M, Kumar S, Saxena A. Imaging of the spectrum of abnormal systemic arterial supply to the lungs using dual-source CT. Clin Radiol 2020; 76:235.e1-235.e14. [PMID: 33293026 DOI: 10.1016/j.crad.2020.11.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2020] [Accepted: 11/03/2020] [Indexed: 10/22/2022]
Abstract
Abnormal systemic arterial supply to the lungs can be seen in various congenital and acquired diseases. Identification and characterisation of aberrant vascular supply is essential for further management and treatment. Multidetector computed tomography (CT) with its multiplanar capabilities and volume-rendering techniques provides precise information regarding the anatomy and spatial relationship of arterial vascular channels. The following concise review elucidates the characteristic imaging findings of conditions in which systemic arteries are seen supplying the lung parenchyma on dual-source CT.
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Patodia J, Mittal J, Sharma V, Verma M, Rathi M, Kumar N, Jain R, Goyal A. Reducing admission hypothermia in newborns at a tertiary care NICU of northern India: A quality improvement study. J Neonatal Perinatal Med 2020; 14:277-286. [PMID: 33044201 DOI: 10.3233/npm-190385] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Hypothermia at admission to neonatal intensive care units (NICU) is associated with increased morbidity and mortality in newborns. A baseline study at a tertiary care hospital with all out-born babies showed admission hypothermia of 82%. OBJECTIVE To reduce admission hypothermia (moderate) in newborns at least by 50% in next 6 months. METHODS A quality improvement (QI) study was planned using WHO Point of Care Quality Improvement Model (POCQI), [17] using PDSA (Plan-Do-Study-Act) cycle approach from April 2018 to March 2019, and including 427 term and preterm babies. We educated the staff, reinforced the use of caps, cling wraps, warm linen, introduced Ziploc bags and ensured adequate use of transport incubator. RESULTS After 6 months, overall admission hypothermia decreased from 82% to 45%, moderate hypothermia reduced from 46% to <10% (P < 0.001) and severe hypothermia (3%) was completely eliminated. There was also significant reduction in incidence of Intraventricular hemorrhage (13% Vs 4.7%), Late onset neonatal sepsis (38% Vs 19%) and metabolic acidosis (43% Vs 28%). We were able to sustain this improvement for the next 6 months and is ongoing. The strongest predictor of hypothermia was newborns being in the phase before QI initiative was started (OR 2.36, 95% CI 1.47, 3.23). CONCLUSION This study is a cost effective approach in reducing admission hypothermia in NICU in a resource limited setting with all outborn babies, and further decreasing the morbidity associated with it. Hence, emphasizing the importance of maintaining euthermia, not only in delivery rooms, but also during transportation.
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Chakrabarti D, Rajan S, Akhtar N, Qayoom S, Verma M, Gupta R. P-14 Dose escalated short-course radiotherapy in rectal cancers: Is this the way forward? Ann Oncol 2020. [DOI: 10.1016/j.annonc.2020.04.096] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Doctor PN, Verma M, Varaiya A, Merchant RH. Emphysematous osteomyelitis caused by Salmonella typhi in beta thalassemia major. J Postgrad Med 2020; 65:41-43. [PMID: 29882519 PMCID: PMC6380132 DOI: 10.4103/jpgm.jpgm_689_17] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
There have been various cases of salmonella osteomyelitis reported in sickle cell anemia. We present a case of emphysematous osteomyelitis caused by Salmonella typhi in a 29-year-old beta thalassemia major patient. Diagnosis of emphysematous osteomyelitis was confirmed by computed tomography and magnetic resonance imaging, and culture of pus drained during surgical debridement confirmed the causative microorganism, Salmonella typhi. Antimicrobials were given according to microbiological sensitivity for a period of 8 weeks. Our patient also received hyperbaric oxygen therapy. At the end of therapy, he was afebrile and laboratory parameters normalized with a residual joint deformity which developed within 3 months.
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Inam B, Inam A, Verma M, Kumar Naik K, Alam A. Antidiabetic Potential of Flavones on Streptozotocin-induced Diabetes Mellitus in Rat. Int J Pharm Investig 2019. [DOI: 10.5530/ijpi.2019.4.36] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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Oak P, Sawant Y, Verma M, Patkar D. Bright vessel sign seen on arterial spin labeling (ASL) and its utility for therapeutic management of hyperacute ischemic stroke. J Neurol Sci 2019. [DOI: 10.1016/j.jns.2019.10.627] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Oak P, Sawant Y, Verma M, Patkar D. Fastest detection of ischemic penumbra using comprehensive 10 minutes MRI protocol including ASAP-ASL, and its utility in treating acute stroke. J Neurol Sci 2019. [DOI: 10.1016/j.jns.2019.10.300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Ghosh A, Gangadharan A, Verma M, Das S, Matai L, Dash DP, Dash D, Mapa K, Chakraborty K. Cellular responses to proteostasis perturbations reveal non-optimal feedback in chaperone networks. Cell Mol Life Sci 2019; 76:1605-1621. [PMID: 30683983 PMCID: PMC11105298 DOI: 10.1007/s00018-019-03013-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Revised: 01/10/2019] [Accepted: 01/15/2019] [Indexed: 11/30/2022]
Abstract
The proteostasis network (PN) comprises a plethora of proteins that are dedicated to aid in protein folding and maintenance; some with overlapping functions. Despite this, there are multiple pathophysiological states associated with depletion of chaperones. This is counter-intuitive, assuming cells have the ability to re-program transcriptional outputs in accordance with its proteostasic limitations. Here, we have used S. cerevisiae to understand how cells respond to different types of proteostasis impairments. We monitored the proteostasis status and transcriptome of single deletions of fourteen different Protein Quality Control (PQC) genes. In most cases, cellular response did not activate proteostasis components or pathways that could either complement the function of the missing PQC gene or restore proteostasis. Over-expression of alternate machineries could restore part of the proteostasis defect in two representative PQC gene deletion strains. We posit that S. cerevisiae inherently lacks the ability to sense and respond optimally to defects in proteostasis caused due to deletion of specific PQC components.
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Naghdi M, Taheran M, Brar SK, Kermanshahi-pour A, Verma M, Surampalli R. Pinewood nanobiochar: A unique carrier for the immobilization of crude laccase by covalent bonding. Int J Biol Macromol 2018; 115:563-571. [DOI: 10.1016/j.ijbiomac.2018.04.105] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2018] [Revised: 03/26/2018] [Accepted: 04/20/2018] [Indexed: 01/26/2023]
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Doctor PN, Choudhari A, Verma M, Merchant RH. Moyamoya syndrome in hemoglobin E-beta thalassemia: A rare presentation and association. J Postgrad Med 2018; 64:240-242. [PMID: 29943740 PMCID: PMC6198700 DOI: 10.4103/jpgm.jpgm_468_17] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
Moyamoya disease is an idiopathic, nonatherosclerotic, noninflammatory, chronic progressive cerebrovascular disease characterized by bilateral stenosis or occlusion of the arteries around the circle of Willis, typically the supraclinoid internal carotid arteries, followed by extensive collateralization, which are prone to thrombosis, aneurysm, and hemorrhage. Secondary moyamoya phenomenon or moyamoya syndrome (MMS) occurs in a wide range of clinical scenarios including prothrombotic states such as sickle cell anemia, but the association with other hemoglobinopathies is less frequently observed. We describe a case of a 25-year-old female with hemoglobin E-beta thalassemia who had a rare presentation of MMS in the form of choreoathetoid movements in the left upper and lower extremities. We describe this association, primarily to emphasize thalassemia as an extremely rare but a potential etiology of MMS. Since MMS is a progressive disease, it is important to diagnose and initiate treatment to prevent worsening of the disease and recurrence of stroke.
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Natrajan S, Singh AR, Shewade HD, Verma M, Bali S. Pre-diagnosis attrition in patients with presumptive MDR-TB in Bhopal, India, 2015: a follow-up study. Public Health Action 2018; 8:95-96. [PMID: 29946527 DOI: 10.5588/pha.18.0015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2018] [Accepted: 04/07/2018] [Indexed: 11/10/2022] Open
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Naghdi M, Taheran M, Brar SK, Kermanshahi-pour A, Verma M, Surampalli R. Biotransformation of carbamazepine by laccase-mediator system: Kinetics, by-products and toxicity assessment. Process Biochem 2018. [DOI: 10.1016/j.procbio.2018.02.009] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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Singh G, Singh V, Wang ZX, Voisin G, Lefebvre F, Navenot JM, Evans B, Verma M, Anderson DW, Schneider JS. Effects of developmental lead exposure on the hippocampal methylome: Influences of sex and timing and level of exposure. Toxicol Lett 2018; 290:63-72. [PMID: 29571894 DOI: 10.1016/j.toxlet.2018.03.021] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Revised: 02/15/2018] [Accepted: 03/19/2018] [Indexed: 12/21/2022]
Abstract
Developmental lead (Pb) exposure results in persistent cognitive/behavioral impairments as well as an elevated risk for developing a variety of diseases in later life. Environmental exposures during development can result in a variety of epigenetic changes, including alterations in DNA methylation, that can influence gene expression patterns and affect the function and development of the nervous system. The present promoter-based methylation microarray profiling study explored the extent to which developmental Pb exposure may modify the methylome of a brain region, hippocampus, known to be sensitive to the effects of Pb exposure. Male and female Long Evans rats were exposed to 0 ppm, 150 ppm, 375 ppm, or 750 ppm Pb through perinatal exposures (gestation through lactation), early postnatal exposures (birth through weaning), or long-term postnatal exposures (birth through postnatal day 55). Results showed a significant contribution of sex to the hippocampal methylome and effects of Pb exposure level, with non-linear dose response effects on methylation. Surprisingly, the developmental period of exposure contributed only a small amount of variance to the overall data and gene ontology (GO) analysis revealed the largest number of overrepresented GO terms in the groups with the lowest level of exposure. The highest number of significant differentially methylated regions was found in females exposed to Pb at the lowest exposure level. Our data reinforce the significant effect that low level Pb exposure may have on gene-specific DNA methylation patterns in brain and that this occurs in a sex-dependent manner.
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Sun Y, Frankenberg C, Wood JD, Schimel DS, Jung M, Guanter L, Drewry DT, Verma M, Porcar-Castell A, Griffis TJ, Gu L, Magney TS, Köhler P, Evans B, Yuen K. OCO-2 advances photosynthesis observation from space via solar-induced chlorophyll fluorescence. Science 2018; 358:358/6360/eaam5747. [PMID: 29026013 DOI: 10.1126/science.aam5747] [Citation(s) in RCA: 151] [Impact Index Per Article: 25.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2016] [Accepted: 07/07/2017] [Indexed: 11/02/2022]
Abstract
Quantifying gross primary production (GPP) remains a major challenge in global carbon cycle research. Spaceborne monitoring of solar-induced chlorophyll fluorescence (SIF), an integrative photosynthetic signal of molecular origin, can assist in terrestrial GPP monitoring. However, the extent to which SIF tracks spatiotemporal variations in GPP remains unresolved. Orbiting Carbon Observatory-2 (OCO-2)'s SIF data acquisition and fine spatial resolution permit direct validation against ground and airborne observations. Empirical orthogonal function analysis shows consistent spatiotemporal correspondence between OCO-2 SIF and GPP globally. A linear SIF-GPP relationship is also obtained at eddy-flux sites covering diverse biomes, setting the stage for future investigations of the robustness of such a relationship across more biomes. Our findings support the central importance of high-quality satellite SIF for studying terrestrial carbon cycle dynamics.
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Alam A, Verma M, Naik K, Choudhary D, Kumar S. Anti-osteoporotic activity of isoflavones from Iris germanica targeting NF-kappaB. Int J Pharm Investig 2018. [DOI: 10.4103/jphi.jphi_36_18] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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Verma M, Sheoran P, Chaudhury A. Application of Nanotechnology for Cancer Treatment. ADVANCES IN ANIMAL BIOTECHNOLOGY AND ITS APPLICATIONS 2018:161-178. [DOI: 10.1007/978-981-10-4702-2_10] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/19/2023]
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Taheran M, Naghdi M, Brar SK, Knystautas EJ, Verma M, Surampalli RY. Degradation of chlortetracycline using immobilized laccase on Polyacrylonitrile-biochar composite nanofibrous membrane. THE SCIENCE OF THE TOTAL ENVIRONMENT 2017; 605-606:315-321. [PMID: 28668742 DOI: 10.1016/j.scitotenv.2017.06.185] [Citation(s) in RCA: 74] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Revised: 06/18/2017] [Accepted: 06/22/2017] [Indexed: 06/07/2023]
Abstract
The continuous release of antibiotic compounds through wastewater effluent into environment has raised concerns about their potential problems for different organisms. Enzymatic degradation with laccase is a green option for removal of pharmaceutical compounds from aqueous media. In this study, laccase was immobilized onto homemade Polyacrylonitrile-biochar composite nanofibrous membrane and the obtained biocatalyst was employed for removal of chlortetracycline, a widely used antibiotic, from aqueous media in continuous mode. The results showed that the immobilized laccase has improved storage, temperature and pH stability compared to free laccase. Also, it retained more than 50% of its initial activity after 7cycles of ABTS oxidation which indicated improved enzyme reusability. Finally, while using immobilized laccase for degradation of chlortetracycline in continuous mode exhibited 58.3%, 40.7% and 22.6% chlortetracycline removal efficiency at flux rates of 1, 2 and 3mL/h∙cm2.
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Rao N, Mangeshkumar V, Bozhko T, Verma M, Wu-Chen W. Botulinum Toxin type A (BTX A) in chronic refractory migraine. J Neurol Sci 2017. [DOI: 10.1016/j.jns.2017.08.508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Verma M, Suryanarayana N, Tuteja U, Thavachelvam K, Rao MK, Bhargava R, Shukla S. Anthrax lethal toxin (LeTx) neutralization by PA domain specific antisera. Toxicon 2017; 139:58-65. [PMID: 28919458 DOI: 10.1016/j.toxicon.2017.09.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2017] [Revised: 08/24/2017] [Accepted: 09/11/2017] [Indexed: 12/23/2022]
Abstract
Anthrax associated causalities in humans and animals are implicated mainly due to the action of two exotoxins that are secreted by the bacterium Bacillus antharcis during the infection. These exotoxins comprise of three protein components namely protective antigen (PA), lethal factor (LF) and edema factor (EF). The protective antigen is the common toxin component required to form both lethal toxin (LeTx) and edema toxin (EdTx). The LeTx is formed, when PA combines with LF and EdTx is formed when PA combines with EF. Therapeutic interventions aiming to neutralize these key effectors of anthrax pathology would therefore, provide an effective means to counter the toxicity imposed by the anthrax toxins on the host. The present work describes the lethal toxin neutralization potential of polyclonal antisera developed against the individual domains of the protective antigen component of the anthrax toxin. The individual domains were produced as recombinant proteins in E. coli and validated with peptide mass fingerprinting by MALDI-TOF analysis and corresponding mice polyclonal antisera by western blotting. Each domain specific antibody titre and isotype was ascertained by ELISA. The isotyping revealed the predominance of IgG1 isotype. The toxin neutralizing potential of these domain specific antisera were evaluated by in-vitro cell viability MTT assay, employing J774.1 mouse macrophage cell line against LeTx (0.25 μg ml-1 PA and 0.125 μg ml-1 LF concentrations). Among the four domain specific antisera, the antiserum against PA domain IV could neutralize LeTx with high efficiency. No significant neutralization of LeTx was observed with other domain specific antibodies. Results indicate that antibodies to r-PA domain IV could be explored further as therapeutic anti toxin molecule along with appropriate antibiotic regimens against anthrax.
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Banerjee H, Verma M, Dutta S. 2-Am,4,6-DNT Causes Genotoxicity of P53 Gene in NG108 Neuroblastoma Cell Lines. INT J HUM GENET 2017. [DOI: 10.1080/09723757.2004.11885898] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Potnis S, Edge GJA, Jackson S, Verma M, Vutha AC. Note: A compact external-cavity diode laser, using feedback from an optical fiber. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2017; 88:096102. [PMID: 28964166 DOI: 10.1063/1.4991709] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2017] [Accepted: 08/22/2017] [Indexed: 06/07/2023]
Abstract
We demonstrate a simple and compact external cavity diode laser (ECDL), where light reflected from the tip of an optical fiber provides feedback, and an interference filter provides frequency selection. The ECDL combines ease of construction with robust operation and exhibits a linewidth of 50 kHz.
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Naghdi M, Taheran M, Brar SK, Kermanshahi-Pour A, Verma M, Surampalli RY. Immobilized laccase on oxygen functionalized nanobiochars through mineral acids treatment for removal of carbamazepine. THE SCIENCE OF THE TOTAL ENVIRONMENT 2017; 584-585:393-401. [PMID: 28117156 DOI: 10.1016/j.scitotenv.2017.01.021] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2016] [Revised: 01/03/2017] [Accepted: 01/04/2017] [Indexed: 05/28/2023]
Abstract
Biocatalytic treatment with oxidoreductase enzymes, especially laccases are an environmentally benign method for biodegradation of pharmaceutical compounds, such as carbamazepine to less harmful compounds. However, enzymes are required to be immobilized on supports to be reusable and maintain their activity. Functionalization of support prior to immobilization of enzyme is highly important because of biomolecule-support interface on enzyme activity and stability. In this work, the effect of oxidation of nanobiochar, a carbonaceous material produced by biomass pyrolysis, using HCl, H2SO4, HNO3 and their mixtures on immobilization of laccase has been studied. Scanning electron microscopy indicated that the structure of nanobiochars remained intact after oxidation and Fourier transform infrared spectroscopy confirmed the formation of carboxylic groups because of acid treatment. Titration measurements showed that the sample treated with H2SO4/HNO3 (50:50, v/v) had the highest number of carboxylic groups (4.7mmol/g) and consequently the highest efficiency for laccase immobilization. Additionally, it was observed that the storage, pH and thermal stability of immobilized laccase on functionalized nanobiochar was improved compared to free laccase showing its potential for continuous applications. The reusability tests towards oxidation of 2, 2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) showed that the immobilized laccase preserved 70% of the initial activity after 3cycles. Finally, using immobilized laccase for degradation of carbamazepine exhibited 83% and 86% removal in spiked water and secondary effluent, respectively.
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Lal P, Yadav R, Misra S, Verma M, Maria Das K, Senthil Kumar S, Kumar S. An Audit of Hypofractionated Radiotherapy (HFRT) in Breast Cancer Patients Treated at a Tertiary Care Academic Centre: Outcomes and Acute Toxicity. Clin Oncol (R Coll Radiol) 2017. [DOI: 10.1016/j.clon.2016.10.023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Taheran M, Naghdi M, Brar SK, Knystautas EJ, Verma M, Ramirez AA, Surampalli RY, Valero JR. Adsorption study of environmentally relevant concentrations of chlortetracycline on pinewood biochar. THE SCIENCE OF THE TOTAL ENVIRONMENT 2016; 571:772-7. [PMID: 27422726 DOI: 10.1016/j.scitotenv.2016.07.050] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Revised: 06/19/2016] [Accepted: 07/06/2016] [Indexed: 05/21/2023]
Abstract
The presence of pharmaceutically active compounds (PhACs) in water and wastewater has raised concerns because of potential environmental impacts and thus their removal is of high importance. The adsorption behavior of chlortetracycline (CTC) from aqueous solution on raw and activated pinewood biochar was studied at 298 K. The effect of initial pH of the solution was studied by performing the experiment at three different pHs (1, 5 and 9). At each pH, CTC showed varied electrostatic charge (+1, 0 and -1, respectively) which affected its adsorption. The results indicated that CTC followed Langmuir isotherm and the related parameters were calculated. Also, it was observed that the maximum adsorption occurred at pH1. The adsorption capacity of CTC for raw and activated biochar was at least 2.1 and 208.3mg/g adsorbent, respectively. The characteristics of biochars were studied using zeta potential analyzer, laser size analyzer and scanning electron microscopy (SEM). The results showed that raw and activated biochars are promising candidates for removal of CTC from water due to the acidic character of pinewood that can result in better interaction with ionizable compounds at lower pHs.
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