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Montaldo P, Burgod C, Herberg JA, Kaforou M, Cunnington AJ, Mejias A, Cirillo G, Miraglia Del Giudice E, Capristo C, Bandiya P, Kamalaratnam CN, Chandramohan R, Manerkar S, Rodrigo R, Sumanasena S, Krishnan V, Pant S, Shankaran S, Thayyil S. Whole-Blood Gene Expression Profile After Hypoxic-Ischemic Encephalopathy. JAMA Netw Open 2024; 7:e2354433. [PMID: 38306098 PMCID: PMC10837749 DOI: 10.1001/jamanetworkopen.2023.54433] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/10/2023] [Accepted: 12/06/2023] [Indexed: 02/03/2024] Open
Abstract
Importance Induced hypothermia, the standard treatment for hypoxic-ischemic encephalopathy (HIE) in high-income countries (HICs), is less effective in the low-income populations in South Asia, who have the highest disease burden. Objective To investigate the differences in blood genome expression profiles of neonates with HIE from an HIC vs neonates with HIE from South Asia. Design, Setting, and Participants This case-control study analyzed data from (1) a prospective observational study involving neonates with moderate or severe HIE who underwent whole-body hypothermia between January 2017 and June 2019 and age-matched term healthy controls in Italy and (2) a randomized clinical trial involving neonates with moderate or severe HIE in India, Sri Lanka, and Bangladesh recruited between August 2015 and February 2019. Data were analyzed between October 2020 and August 2023. Exposure Whole-blood RNA that underwent next-generation sequencing. Main Outcome and Measures The primary outcomes were whole-blood genome expression profile at birth associated with adverse outcome (death or disability at 18 months) after HIE in the HIC and South Asia cohorts and changes in whole-genome expression profile during the first 72 hours after birth in neonates with HIE and healthy controls from the HIC cohort. Blood samples for RNA extraction were collected before whole-body hypothermia at 4 time points (6, 24, 48, and 72 hours after birth) for the HIC cohort. Only 1 blood sample was drawn within 6 hours after birth for the South Asia cohort. Results The HIC cohort was composed of 35 neonates (21 females [60.0%]) with a median (IQR) birth weight of 3.3 (3.0-3.6) kg and gestational age of 40.0 (39.0-40.6) weeks. The South Asia cohort consisted of 99 neonates (57 males [57.6%]) with a median (IQR) birth weight of 2.9 (2.7-3.3) kg and gestational age of 39.0 (38.0-40.0) weeks. Healthy controls included 14 neonates (9 females [64.3%]) with a median (IQR) birth weight of 3.4 (3.2-3.7) kg and gestational age of 39.2 (38.9-40.4) weeks. A total of 1793 significant genes in the HIC cohort and 99 significant genes in the South Asia cohort were associated with adverse outcome (false discovery rate <0.05). Only 11 of these genes were in common, and all had opposite direction in fold change. The most significant pathways associated with adverse outcome were downregulation of eukaryotic translation initiation factor 2 signaling in the HIC cohort (z score = -4.56; P < .001) and aldosterone signaling in epithelial cells in the South Asia cohort (z score = null; P < .001). The genome expression profile of neonates with HIE (n = 35) at birth, 24 hours, 48 hours, and 72 hours remained significantly different from that of age-matched healthy controls in the HIC cohort (n = 14). Conclusions and Relevance This case-control study found that disease mechanisms underlying HIE were primarily associated with acute hypoxia in the HIC cohort and nonacute hypoxia in the South Asia cohort. This finding might explain the lack of hypothermic neuroprotection.
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Affiliation(s)
- Paolo Montaldo
- Centre for Perinatal Neuroscience, Department of Brain Sciences, Imperial College London, London, United Kingdom
- Department of Women's and Children's Health and General and Specialized Surgery, University of Campania Luigi Vanvitelli, Naples, Italy
| | - Constance Burgod
- Centre for Perinatal Neuroscience, Department of Brain Sciences, Imperial College London, London, United Kingdom
| | - Jethro A. Herberg
- Section of Paediatric Infectious Disease and Centre for Paediatrics and Child Health, Department of Infectious Disease, Imperial College London, London, United Kingdom
| | - Myrsini Kaforou
- Section of Paediatric Infectious Disease and Centre for Paediatrics and Child Health, Department of Infectious Disease, Imperial College London, London, United Kingdom
| | - Aubrey J. Cunnington
- Section of Paediatric Infectious Disease and Centre for Paediatrics and Child Health, Department of Infectious Disease, Imperial College London, London, United Kingdom
| | - Asuncion Mejias
- Department of Infectious Diseases, St Jude Children’s Research Hospital, Memphis, Tennessee
- Center for Vaccines and Immunity, Abigail Wexner Research Institute at Nationwide Children’s Hospital, Columbus, Ohio
| | - Grazia Cirillo
- Department of Women's and Children's Health and General and Specialized Surgery, University of Campania Luigi Vanvitelli, Naples, Italy
| | - Emanuele Miraglia Del Giudice
- Department of Women's and Children's Health and General and Specialized Surgery, University of Campania Luigi Vanvitelli, Naples, Italy
| | - Carlo Capristo
- Department of Women's and Children's Health and General and Specialized Surgery, University of Campania Luigi Vanvitelli, Naples, Italy
| | - Prathik Bandiya
- Department of Neonatology, Indira Gandhi Institute of Child Health, Bengaluru, India
| | | | - Rema Chandramohan
- Institute of Child Health, Department of Neonatology, Madras Medical College, Chennai, India
| | - Swati Manerkar
- Department of Neonatology, Lokmanya Tilak Municipal Medical College, Mumbai, India
| | - Ranmali Rodrigo
- Department of Pediatrics, University of Kelaniya, Colombo, Sri Lanka
| | | | - Vaisakh Krishnan
- Centre for Perinatal Neuroscience, Department of Brain Sciences, Imperial College London, London, United Kingdom
| | - Stuti Pant
- Centre for Perinatal Neuroscience, Department of Brain Sciences, Imperial College London, London, United Kingdom
| | - Seetha Shankaran
- Neonatal-Perinatal Medicine, Wayne State University, Detroit, Michigan
| | - Sudhin Thayyil
- Centre for Perinatal Neuroscience, Department of Brain Sciences, Imperial College London, London, United Kingdom
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Burgod C, Mazlan M, Pant S, Krishnan V, Garegrat R, Montaldo P, Muraleedharan P, Bandiya P, Kamalaratnam CN, Chandramohan R, Manerkar S, Jahan I, Moni SC, Shahidullah M, Rodrigo R, Sumanasena S, Sujatha R, Sathyanathan BP, Joshi AR, Pressler RR, Bassett P, Shankaran S, Thayyil S. Duration of birth depression and neurodevelopmental outcomes after whole-body hypothermia for hypoxic ischemic encephalopathy in India, Sri Lanka and Bangladesh - an exploratory analysis of the HELIX trial. Lancet Reg Health Southeast Asia 2024; 20:100284. [PMID: 38234698 PMCID: PMC10794099 DOI: 10.1016/j.lansea.2023.100284] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 09/01/2023] [Accepted: 09/11/2023] [Indexed: 01/19/2024]
Abstract
Background Effect of duration of birth depression on neurodevelopmental outcomes in low- and middle-income countries (LMICs) is not known. We examined the association of birth depression with brain injury, neurodevelopmental outcomes, and hypothermia after hypoxic ischemic encephalopathy (HIE) in south Asia. Methods We compared cerebral magnetic resonance (MR) at 2 weeks, and adverse outcomes (death or moderate or severe disability) at 18 months in 408 babies with moderate or severe HIE who had long birth depression (positive pressure ventilation (PPV) >10 min or Apgar score<6 at 10 min or cord pH < 7.0) and short birth depression (PPV for 5-10 min or Apgar score<6 at 5 min, but ≥6 at 10 min). Findings Long depression group (n = 201) had more severe HIE (32.8% versus 6.8%), mortality (47.5% versus 26.4%), death or disability at 18 months (62.2% versus 35.4%) (all p < 0.001), MR injury (Odds ratio; 95% CI) to basal ganglia (2.4 (1.3, 4.1); p = 0.003), posterior limb of internal capsule (2.3 (1.3, 4.3); p < 0.001) and white matter (1.7 (1.1, 2.7); p = 0.021), and lower thalamic N-acetylaspartate levels (7.69 ± 1.84 versus 8.29 ± 1.60); p = 0.031) than short depression group (n = 207). Three babies had no heartbeat at 5 min, of which 1 died and 2 survived with severe disability. No significant interaction between the duration of birth depression and whole-body hypothermia was seen for any of the MR biomarker or clinical outcomes. Interpretation Long birth depression was associated with more brain injury and adverse outcomes than short depression. Effect of hypothermia was not modified by duration of birth depression. Funding National Institute for Health Research.
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Affiliation(s)
- Constance Burgod
- Centre for Perinatal Neuroscience, Imperial College, London, United Kingdom
| | - Munirah Mazlan
- Centre for Perinatal Neuroscience, Imperial College, London, United Kingdom
| | - Stuti Pant
- Centre for Perinatal Neuroscience, Imperial College, London, United Kingdom
| | - Vaisakh Krishnan
- Centre for Perinatal Neuroscience, Imperial College, London, United Kingdom
| | - Reema Garegrat
- Centre for Perinatal Neuroscience, Imperial College, London, United Kingdom
| | - Paolo Montaldo
- Centre for Perinatal Neuroscience, Imperial College, London, United Kingdom
| | | | - Prathik Bandiya
- Neonatal Unit, Indira Gandhi Institute of Child Health, Bangalore, India
| | | | | | - Swati Manerkar
- Neonatal Unit and Radiology, Lokmanya Tilak Municipal Medical College, Mumbai, India
| | - Ismat Jahan
- Neonatal Unit, Bangabandhu Sheikh Mujib Medical University, Bangladesh
| | - Sadeka C. Moni
- Neonatal Unit, Bangabandhu Sheikh Mujib Medical University, Bangladesh
| | | | | | | | - Radhika Sujatha
- Neonatal Unit, Sree Avittom Thirunal Hospital and Government Medical College, Thiruvananthapuram, India
| | | | - Anagha R. Joshi
- Neonatal Unit and Radiology, Lokmanya Tilak Municipal Medical College, Mumbai, India
| | - Ronit R. Pressler
- Department of Neurophysiology, Great Ormond Street Hospital, United Kingdom
| | | | - Seetha Shankaran
- Department of Neonatal-Perinatal Medicine, Wayne State University, Detroit, MI, USA
- University of Texas at Austin, Dell Children's Hospital, Austin, USA
| | - Sudhin Thayyil
- Centre for Perinatal Neuroscience, Imperial College, London, United Kingdom
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Thayyil S, Montaldo P, Krishnan V, Ivain P, Pant S, Lally PJ, Bandiya P, Benkappa N, Kamalaratnam CN, Chandramohan R, Manerkar S, Mondkar J, Jahan I, Moni SC, Shahidullah M, Rodrigo R, Sumanasena S, Sujatha R, Burgod C, Garegrat R, Mazlan M, Chettri I, Babu Peter S, Joshi AR, Swamy R, Chong K, Pressler RR, Bassett P, Shankaran S. Whole-Body Hypothermia, Cerebral Magnetic Resonance Biomarkers, and Outcomes in Neonates With Moderate or Severe Hypoxic-Ischemic Encephalopathy Born at Tertiary Care Centers vs Other Facilities: A Nested Study Within a Randomized Clinical Trial. JAMA Netw Open 2023; 6:e2312152. [PMID: 37155168 PMCID: PMC10167567 DOI: 10.1001/jamanetworkopen.2023.12152] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 05/10/2023] Open
Abstract
Importance The association between place of birth and hypothermic neuroprotection after hypoxic-ischemic encephalopathy (HIE) in low- and middle-income countries (LMICs) is unknown. Objective To ascertain the association between place of birth and the efficacy of whole-body hypothermia for protection against brain injury measured by magnetic resonance (MR) biomarkers among neonates born at a tertiary care center (inborn) or other facilities (outborn). Design, Setting, and Participants This nested cohort study within a randomized clinical trial involved neonates at 7 tertiary neonatal intensive care units in India, Sri Lanka, and Bangladesh between August 15, 2015, and February 15, 2019. A total of 408 neonates born at or after 36 weeks' gestation with moderate or severe HIE were randomized to receive whole-body hypothermia (reduction of rectal temperatures to between 33.0 °C and 34.0 °C; hypothermia group) for 72 hours or no whole-body hypothermia (rectal temperatures maintained between 36.0 °C and 37.0 °C; control group) within 6 hours of birth, with follow-up until September 27, 2020. Exposure 3T MR imaging, MR spectroscopy, and diffusion tensor imaging. Main Outcomes and Measures Thalamic N-acetyl aspartate (NAA) mmol/kg wet weight, thalamic lactate to NAA peak area ratios, brain injury scores, and white matter fractional anisotropy at 1 to 2 weeks and death or moderate or severe disability at 18 to 22 months. Results Among 408 neonates, the mean (SD) gestational age was 38.7 (1.3) weeks; 267 (65.4%) were male. A total of 123 neonates were inborn and 285 were outborn. Inborn neonates were smaller (mean [SD], 2.8 [0.5] kg vs 2.9 [0.4] kg; P = .02), more likely to have instrumental or cesarean deliveries (43.1% vs 24.7%; P = .01), and more likely to be intubated at birth (78.9% vs 29.1%; P = .001) than outborn neonates, although the rate of severe HIE was not different (23.6% vs 17.9%; P = .22). Magnetic resonance data from 267 neonates (80 inborn and 187 outborn) were analyzed. In the hypothermia vs control groups, the mean (SD) thalamic NAA levels were 8.04 (1.98) vs 8.31 (1.13) among inborn neonates (odds ratio [OR], -0.28; 95% CI, -1.62 to 1.07; P = .68) and 8.03 (1.89) vs 7.99 (1.72) among outborn neonates (OR, 0.05; 95% CI, -0.62 to 0.71; P = .89); the median (IQR) thalamic lactate to NAA peak area ratios were 0.13 (0.10-0.20) vs 0.12 (0.09-0.18) among inborn neonates (OR, 1.02; 95% CI, 0.96-1.08; P = .59) and 0.14 (0.11-0.20) vs 0.14 (0.10-0.17) among outborn neonates (OR, 1.03; 95% CI, 0.98-1.09; P = .18). There was no difference in brain injury scores or white matter fractional anisotropy between the hypothermia and control groups among inborn or outborn neonates. Whole-body hypothermia was not associated with reductions in death or disability, either among 123 inborn neonates (hypothermia vs control group: 34 neonates [58.6%] vs 34 [56.7%]; risk ratio, 1.03; 95% CI, 0.76-1.41), or 285 outborn neonates (hypothermia vs control group: 64 neonates [46.7%] vs 60 [43.2%]; risk ratio, 1.08; 95% CI, 0.83-1.41). Conclusions and Relevance In this nested cohort study, whole-body hypothermia was not associated with reductions in brain injury after HIE among neonates in South Asia, irrespective of place of birth. These findings do not support the use of whole-body hypothermia for HIE among neonates in LMICs. Trial Registration ClinicalTrials.gov Identifier: NCT02387385.
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Affiliation(s)
- Sudhin Thayyil
- Centre for Perinatal Neuroscience, Department of Brain Sciences, Imperial College London, London, United Kingdom
| | - Paolo Montaldo
- Centre for Perinatal Neuroscience, Department of Brain Sciences, Imperial College London, London, United Kingdom
- Neonatal Unit, University of Campania Luigi Vanvitelli, Naples, Italy
| | - Vaisakh Krishnan
- Centre for Perinatal Neuroscience, Department of Brain Sciences, Imperial College London, London, United Kingdom
| | - Phoebe Ivain
- Centre for Perinatal Neuroscience, Department of Brain Sciences, Imperial College London, London, United Kingdom
| | - Stuti Pant
- Centre for Perinatal Neuroscience, Department of Brain Sciences, Imperial College London, London, United Kingdom
| | - Peter J Lally
- Centre for Perinatal Neuroscience, Department of Brain Sciences, Imperial College London, London, United Kingdom
| | - Prathik Bandiya
- Neonatal Unit, Indira Gandhi Institute of Child Health, Bengaluru, India
| | - Naveen Benkappa
- Neonatal Unit, Indira Gandhi Institute of Child Health, Bengaluru, India
| | | | | | - Swati Manerkar
- Neonatal Unit, Lokmanya Tilak Municipal Medical College, Mumbai, India
| | - Jayshree Mondkar
- Neonatal Unit, Lokmanya Tilak Municipal Medical College, Mumbai, India
| | - Ismat Jahan
- Neonatal Unit, Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh
| | - Sadeka C Moni
- Neonatal Unit, Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh
| | | | - Ranmali Rodrigo
- Department of Pediatrics, University of Kelaniya, Kelaniya, Sri Lanka
| | | | - Radhika Sujatha
- Neonatal Unit, Sree Avittom Thirunal Hospital, Government Medical College, Thiruvananthapuram, India
| | - Constance Burgod
- Centre for Perinatal Neuroscience, Department of Brain Sciences, Imperial College London, London, United Kingdom
| | - Reema Garegrat
- Centre for Perinatal Neuroscience, Department of Brain Sciences, Imperial College London, London, United Kingdom
| | - Munirah Mazlan
- Centre for Perinatal Neuroscience, Department of Brain Sciences, Imperial College London, London, United Kingdom
| | - Ismita Chettri
- Centre for Perinatal Neuroscience, Department of Brain Sciences, Imperial College London, London, United Kingdom
| | | | - Anagha R Joshi
- Department of Radiology, Lokmanya Tilak Municipal Medical College, Mumbai, India
| | - Ravi Swamy
- Centre for Perinatal Neuroscience, Department of Brain Sciences, Imperial College London, London, United Kingdom
| | - Kling Chong
- Department of Neuroradiology, Great Ormond Street Hospital, London, United Kingdom
| | - Ronit R Pressler
- Department of Neurophysiology, Great Ormond Street Hospital, London, United Kingdom
| | | | - Seetha Shankaran
- Division of Neonatal-Perinatal Medicine, Wayne State University, Detroit, Michigan
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Naaraayan SA, Dhakshayani RV, Chandramohan R. Monogenic Diabetes — A Case Series. Indian Pediatr 2022. [DOI: 10.1007/s13312-021-2403-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Naaraayan SA, Dhakshayani RV, Chandramohan R. Monogenic Diabetes -A Case Series. Indian Pediatr 2021; 58:1185-1186. [PMID: 34939583] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Affiliation(s)
- Sridevi A Naaraayan
- Diabetes clinic, Institute of Child Health and Hospital for Children, Egmore, Chennai,Tamil Nadu.
| | - Raghavan V Dhakshayani
- Diabetes clinic, Institute of Child Health and Hospital for Children, Egmore, Chennai, Tamil Nadu
| | - Rema Chandramohan
- Diabetes clinic, Institute of Child Health and Hospital for Children, Egmore, Chennai, Tamil Nadu
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Thayyil S, Pant S, Montaldo P, Shukla D, Oliveira V, Ivain P, Bassett P, Swamy R, Mendoza J, Moreno-Morales M, Lally PJ, Benakappa N, Bandiya P, Shivarudhrappa I, Somanna J, Kantharajanna UB, Rajvanshi A, Krishnappa S, Joby PK, Jayaraman K, Chandramohan R, Kamalarathnam CN, Sebastian M, Tamilselvam IA, Rajendran UD, Soundrarajan R, Kumar V, Sudarsanan H, Vadakepat P, Gopalan K, Sundaram M, Seeralar A, Vinayagam P, Sajjid M, Baburaj M, Murugan KD, Sathyanathan BP, Kumaran ES, Mondkar J, Manerkar S, Joshi AR, Dewang K, Bhisikar SM, Kalamdani P, Bichkar V, Patra S, Jiwnani K, Shahidullah M, Moni SC, Jahan I, Mannan MA, Dey SK, Nahar MN, Islam MN, Shabuj KH, Rodrigo R, Sumanasena S, Abayabandara-Herath T, Chathurangika GK, Wanigasinghe J, Sujatha R, Saraswathy S, Rahul A, Radha SJ, Sarojam MK, Krishnan V, Nair MK, Devadas S, Chandriah S, Venkateswaran H, Burgod C, Chandrasekaran M, Atreja G, Muraleedharan P, Herberg JA, Kling Chong WK, Sebire NJ, Pressler R, Ramji S, Shankaran S. Hypothermia for moderate or severe neonatal encephalopathy in low-income and middle-income countries (HELIX): a randomised controlled trial in India, Sri Lanka, and Bangladesh. Lancet Glob Health 2021; 9:e1273-e1285. [PMID: 34358491 PMCID: PMC8371331 DOI: 10.1016/s2214-109x(21)00264-3] [Citation(s) in RCA: 112] [Impact Index Per Article: 37.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 05/26/2021] [Accepted: 05/27/2021] [Indexed: 01/18/2023]
Abstract
BACKGROUND Although therapeutic hypothermia reduces death or disability after neonatal encephalopathy in high-income countries, its safety and efficacy in low-income and middle-income countries is unclear. We aimed to examine whether therapeutic hypothermia alongside optimal supportive intensive care reduces death or moderate or severe disability after neonatal encephalopathy in south Asia. METHODS We did a multicountry open-label, randomised controlled trial in seven tertiary neonatal intensive care units in India, Sri Lanka, and Bangladesh. We enrolled infants born at or after 36 weeks of gestation with moderate or severe neonatal encephalopathy and a need for continued resuscitation at 5 min of age or an Apgar score of less than 6 at 5 min of age (for babies born in a hospital), or both, or an absence of crying by 5 min of age (for babies born at home). Using a web-based randomisation system, we allocated infants into a group receiving whole body hypothermia (33·5°C) for 72 h using a servo-controlled cooling device, or to usual care (control group), within 6 h of birth. All recruiting sites had facilities for invasive ventilation, cardiovascular support, and access to 3 Tesla MRI scanners and spectroscopy. Masking of the intervention was not possible, but those involved in the magnetic resonance biomarker analysis and neurodevelopmental outcome assessments were masked to the allocation. The primary outcome was a combined endpoint of death or moderate or severe disability at 18-22 months, assessed by the Bayley Scales of Infant and Toddler Development (third edition) and a detailed neurological examination. Analysis was by intention to treat. This trial is registered with ClinicalTrials.gov, NCT02387385. FINDINGS We screened 2296 infants between Aug 15, 2015, and Feb 15, 2019, of whom 576 infants were eligible for inclusion. After exclusions, we recruited 408 eligible infants and we assigned 202 to the hypothermia group and 206 to the control group. Primary outcome data were available for 195 (97%) of the 202 infants in the hypothermia group and 199 (97%) of the 206 control group infants. 98 (50%) infants in the hypothermia group and 94 (47%) infants in the control group died or had a moderate or severe disability (risk ratio 1·06; 95% CI 0·87-1·30; p=0·55). 84 infants (42%) in the hypothermia group and 63 (31%; p=0·022) infants in the control group died, of whom 72 (36%) and 49 (24%; p=0·0087) died during neonatal hospitalisation. Five serious adverse events were reported: three in the hypothermia group (one hospital readmission relating to pneumonia, one septic arthritis, and one suspected venous thrombosis), and two in the control group (one related to desaturations during MRI and other because of endotracheal tube displacement during transport for MRI). No adverse events were considered causally related to the study intervention. INTERPRETATION Therapeutic hypothermia did not reduce the combined outcome of death or disability at 18 months after neonatal encephalopathy in low-income and middle-income countries, but significantly increased death alone. Therapeutic hypothermia should not be offered as treatment for neonatal encephalopathy in low-income and middle-income countries, even when tertiary neonatal intensive care facilities are available. FUNDING National Institute for Health Research, Garfield Weston Foundation, and Bill & Melinda Gates Foundation. TRANSLATIONS For the Hindi, Malayalam, Telugu, Kannada, Singhalese, Tamil, Marathi and Bangla translations of the abstract see Supplementary Materials section.
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Affiliation(s)
- Sudhin Thayyil
- Centre for Perinatal Neuroscience, Imperial College London, London, UK.
| | - Stuti Pant
- Centre for Perinatal Neuroscience, Imperial College London, London, UK
| | - Paolo Montaldo
- Centre for Perinatal Neuroscience, Imperial College London, London, UK
| | - Deepika Shukla
- Centre for Perinatal Neuroscience, Imperial College London, London, UK
| | - Vania Oliveira
- Centre for Perinatal Neuroscience, Imperial College London, London, UK
| | - Phoebe Ivain
- Centre for Perinatal Neuroscience, Imperial College London, London, UK
| | | | - Ravi Swamy
- Perinatal Epidemiology Unit, Bengaluru, Karnataka, India
| | - Josephine Mendoza
- Centre for Perinatal Neuroscience, Imperial College London, London, UK
| | | | - Peter J Lally
- Centre for Perinatal Neuroscience, Imperial College London, London, UK
| | - Naveen Benakappa
- Indira Gandhi Institute of Child Health, Bengaluru, Karnataka, India
| | - Prathik Bandiya
- Indira Gandhi Institute of Child Health, Bengaluru, Karnataka, India
| | - Indramma Shivarudhrappa
- Perinatal Epidemiology Unit, Bengaluru, Karnataka, India; Indira Gandhi Institute of Child Health, Bengaluru, Karnataka, India; Institute of Obstetrics and Gynaecology and Government Hospital for Women and Children, Madras Medical College, Chennai, India
| | - Jagadish Somanna
- Indira Gandhi Institute of Child Health, Bengaluru, Karnataka, India
| | | | - Ankur Rajvanshi
- Indira Gandhi Institute of Child Health, Bengaluru, Karnataka, India
| | - Sowmya Krishnappa
- Indira Gandhi Institute of Child Health, Bengaluru, Karnataka, India
| | | | | | | | | | - Monica Sebastian
- Perinatal Epidemiology Unit, Bengaluru, Karnataka, India; Institute of Child Health, Madras Medical College, Chennai, India
| | | | - Usha D Rajendran
- Institute of Child Health, Madras Medical College, Chennai, India
| | | | - Vignesh Kumar
- Institute of Child Health, Madras Medical College, Chennai, India
| | | | - Padmesh Vadakepat
- Institute of Child Health, Madras Medical College, Chennai, India; Institute of Obstetrics and Gynaecology and Government Hospital for Women and Children, Madras Medical College, Chennai, India
| | - Kavitha Gopalan
- Institute of Child Health, Madras Medical College, Chennai, India
| | - Mangalabharathi Sundaram
- Institute of Obstetrics and Gynaecology and Government Hospital for Women and Children, Madras Medical College, Chennai, India
| | - Arasar Seeralar
- Institute of Obstetrics and Gynaecology and Government Hospital for Women and Children, Madras Medical College, Chennai, India
| | - Prakash Vinayagam
- Institute of Obstetrics and Gynaecology and Government Hospital for Women and Children, Madras Medical College, Chennai, India
| | - Mohamed Sajjid
- Institute of Obstetrics and Gynaecology and Government Hospital for Women and Children, Madras Medical College, Chennai, India
| | - Mythili Baburaj
- Perinatal Epidemiology Unit, Bengaluru, Karnataka, India; Institute of Obstetrics and Gynaecology and Government Hospital for Women and Children, Madras Medical College, Chennai, India
| | - Kanchana D Murugan
- Institute of Obstetrics and Gynaecology and Government Hospital for Women and Children, Madras Medical College, Chennai, India
| | | | | | - Jayashree Mondkar
- Lokmanya Tilak Municipal Medical College, Mumbai, Maharashtra, India
| | - Swati Manerkar
- Lokmanya Tilak Municipal Medical College, Mumbai, Maharashtra, India
| | - Anagha R Joshi
- Lokmanya Tilak Municipal Medical College, Mumbai, Maharashtra, India
| | - Kapil Dewang
- Lokmanya Tilak Municipal Medical College, Mumbai, Maharashtra, India
| | | | - Pavan Kalamdani
- Lokmanya Tilak Municipal Medical College, Mumbai, Maharashtra, India
| | - Vrushali Bichkar
- Lokmanya Tilak Municipal Medical College, Mumbai, Maharashtra, India
| | - Saikat Patra
- Lokmanya Tilak Municipal Medical College, Mumbai, Maharashtra, India
| | - Kapil Jiwnani
- Lokmanya Tilak Municipal Medical College, Mumbai, Maharashtra, India
| | | | - Sadeka C Moni
- Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh
| | - Ismat Jahan
- Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh
| | | | - Sanjoy K Dey
- Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh
| | - Mst N Nahar
- National Institute of Neurosciences, Dhaka, Bangladesh
| | | | - Kamrul H Shabuj
- Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh
| | | | | | | | | | | | - Radhika Sujatha
- Sree Avittom Thirunal Hospital and Government Medical College, Thiruvananthapuram, Kerala, India
| | - Sobhakumar Saraswathy
- Sree Avittom Thirunal Hospital and Government Medical College, Thiruvananthapuram, Kerala, India
| | - Aswathy Rahul
- Sree Avittom Thirunal Hospital and Government Medical College, Thiruvananthapuram, Kerala, India
| | - Saritha J Radha
- Sree Avittom Thirunal Hospital and Government Medical College, Thiruvananthapuram, Kerala, India
| | - Manoj K Sarojam
- Sree Avittom Thirunal Hospital and Government Medical College, Thiruvananthapuram, Kerala, India
| | - Vaisakh Krishnan
- Institute of Maternal and Child Health, Government Medical College, Kozhikode, Kerala, India
| | - Mohandas K Nair
- Institute of Maternal and Child Health, Government Medical College, Kozhikode, Kerala, India
| | - Sahana Devadas
- Vanivilas Hospital, Bangalore Medical College and Research Institute, Karnataka, India
| | - Savitha Chandriah
- Vanivilas Hospital, Bangalore Medical College and Research Institute, Karnataka, India
| | | | - Constance Burgod
- Centre for Perinatal Neuroscience, Imperial College London, London, UK
| | | | - Gaurav Atreja
- Centre for Perinatal Neuroscience, Imperial College London, London, UK
| | | | - Jethro A Herberg
- Section of Paediatric Infectious Disease, Imperial College London, London, UK
| | - W K Kling Chong
- Centre for Perinatal Neuroscience, Imperial College London, London, UK; Department of Neuroradiology, Great Ormond Street Hospital, London, UK
| | - Neil J Sebire
- Perinatal Pathology, National Institute for Health Research Biomedical Research Centre, Great Ormond Street Hospital for Children, University College London, London, UK
| | - Ronit Pressler
- Department of Neurophysiology, Great Ormond Street Hospital, London, UK
| | | | - Seetha Shankaran
- Neonatal-Perinatal Medicine, Wayne State University, Detroit, MI, USA
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Naaraayan S, Dhakshayani R, Chandramohan R. Autoimmunity in south Indian children with recently diagnosed type 1 diabetes mellitus. J Diabetol 2021. [DOI: 10.4103/jod.jod_73_20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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Montaldo P, Cunnington A, Oliveira V, Swamy R, Bandya P, Pant S, Lally PJ, Ivain P, Mendoza J, Atreja G, Padmesh V, Baburaj M, Sebastian M, Yasashwi I, Kamalarathnam C, Chandramohan R, Mangalabharathi S, Kumaraswami K, Kumar S, Benakappa N, Manerkar S, Mondhkar J, Prakash V, Sajjid M, Seeralar A, Jahan I, Moni SC, Shahidullah M, Sujatha R, Chandrasekaran M, Ramji S, Shankaran S, Kaforou M, Herberg J, Thayyil S. Transcriptomic profile of adverse neurodevelopmental outcomes after neonatal encephalopathy. Sci Rep 2020; 10:13100. [PMID: 32753750 PMCID: PMC7403382 DOI: 10.1038/s41598-020-70131-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Accepted: 06/16/2020] [Indexed: 12/20/2022] Open
Abstract
A rapid and early diagnostic test to identify the encephalopathic babies at risk of adverse outcome may accelerate the development of neuroprotectants. We examined if a whole blood transcriptomic signature measured soon after birth, predicts adverse neurodevelopmental outcome eighteen months after neonatal encephalopathy. We performed next generation sequencing on whole blood ribonucleic acid obtained within six hours of birth from the first 47 encephalopathic babies recruited to the Hypothermia for Encephalopathy in Low and middle-income countries (HELIX) trial. Two infants with blood culture positive sepsis were excluded, and the data from remaining 45 were analysed. A total of 855 genes were significantly differentially expressed between the good and adverse outcome groups, of which RGS1 and SMC4 were the most significant. Biological pathway analysis adjusted for gender, trial randomisation allocation (cooling therapy versus usual care) and estimated blood leukocyte proportions revealed over-representation of genes from pathways related to melatonin and polo-like kinase in babies with adverse outcome. These preliminary data suggest that transcriptomic profiling may be a promising tool for rapid risk stratification in neonatal encephalopathy. It may provide insights into biological mechanisms and identify novel therapeutic targets for neuroprotection.
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Affiliation(s)
- Paolo Montaldo
- Department of Brain Sciences, Centre for Perinatal Neuroscience, Imperial College London, London, UK. .,Neonatal Unit, Università Degli Studi Della Campania "Luigi Vanvitelli", Naples, Italy.
| | - Aubrey Cunnington
- Paediatric Infectious Diseases, Department of Infectious Diseases, Imperial College London, London, UK
| | - Vania Oliveira
- Department of Brain Sciences, Centre for Perinatal Neuroscience, Imperial College London, London, UK
| | - Ravi Swamy
- Department of Brain Sciences, Centre for Perinatal Neuroscience, Imperial College London, London, UK
| | - Prathik Bandya
- Neonatal Medicine, Indira Gandhi Institute of Child Health, Bangalore, Karnataka, India
| | - Stuti Pant
- Department of Brain Sciences, Centre for Perinatal Neuroscience, Imperial College London, London, UK
| | - Peter J Lally
- Department of Brain Sciences, Centre for Perinatal Neuroscience, Imperial College London, London, UK
| | - Phoebe Ivain
- Department of Brain Sciences, Centre for Perinatal Neuroscience, Imperial College London, London, UK
| | - Josephine Mendoza
- Department of Brain Sciences, Centre for Perinatal Neuroscience, Imperial College London, London, UK
| | - Gaurav Atreja
- Department of Brain Sciences, Centre for Perinatal Neuroscience, Imperial College London, London, UK
| | - Vadakepat Padmesh
- Neonatal Medicine, Institute of Obstetrics and Gynaecology, Madras Medical College, Chennai, Tamil Nadu, India
| | - Mythili Baburaj
- Neonatal Medicine, Institute of Obstetrics and Gynaecology, Madras Medical College, Chennai, Tamil Nadu, India
| | - Monica Sebastian
- Neonatal Medicine, Institute of Child Health, Madras Medical College, Tamil Nadu, Chennai, India
| | - Indiramma Yasashwi
- Neonatal Medicine, Indira Gandhi Institute of Child Health, Bangalore, Karnataka, India
| | - Chinnathambi Kamalarathnam
- Neonatal Medicine, Institute of Obstetrics and Gynaecology, Madras Medical College, Chennai, Tamil Nadu, India
| | - Rema Chandramohan
- Neonatal Medicine, Institute of Obstetrics and Gynaecology, Madras Medical College, Chennai, Tamil Nadu, India
| | - Sundaram Mangalabharathi
- Neonatal Medicine, Institute of Obstetrics and Gynaecology, Madras Medical College, Chennai, Tamil Nadu, India
| | - Kumutha Kumaraswami
- Neonatal Medicine, Institute of Obstetrics and Gynaecology, Madras Medical College, Chennai, Tamil Nadu, India
| | - Shobha Kumar
- Neonatal Medicine, Institute of Obstetrics and Gynaecology, Madras Medical College, Chennai, Tamil Nadu, India
| | - Naveen Benakappa
- Neonatal Medicine, Indira Gandhi Institute of Child Health, Bangalore, Karnataka, India
| | | | | | - Vinayagam Prakash
- Neonatal Medicine, Institute of Obstetrics and Gynaecology, Madras Medical College, Chennai, Tamil Nadu, India
| | - Mohammed Sajjid
- Neonatal Medicine, Institute of Obstetrics and Gynaecology, Madras Medical College, Chennai, Tamil Nadu, India
| | - Arasar Seeralar
- Neonatal Medicine, Institute of Child Health, Madras Medical College, Tamil Nadu, Chennai, India
| | - Ismat Jahan
- Neonatal Medicine, Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh
| | | | - Mohammod Shahidullah
- Neonatal Medicine, Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh
| | - Radhika Sujatha
- Neonatal Medicine, Government Medical College, Thiruvananthapuram, Kerala, India
| | - Manigandan Chandrasekaran
- Department of Brain Sciences, Centre for Perinatal Neuroscience, Imperial College London, London, UK
| | - Siddarth Ramji
- Neonatal Medicine, Maulana Azad Medical College, New Delhi, Delhi, India
| | - Seetha Shankaran
- Neonatal-Perinatal Medicine, Wayne State University, Detroit, MI, USA
| | - Myrsini Kaforou
- Paediatric Infectious Diseases, Department of Infectious Diseases, Imperial College London, London, UK
| | - Jethro Herberg
- Paediatric Infectious Diseases, Department of Infectious Diseases, Imperial College London, London, UK
| | - Sudhin Thayyil
- Department of Brain Sciences, Centre for Perinatal Neuroscience, Imperial College London, London, UK
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Naaraayan SA, Varadharajan P, Dhakshayani RV, Chandramohan R, Senniappan S. Free Style Libre Pro (FSLP) Flash Glucose Monitor (FGM) - A Novel Monitoring Tool for Children with Type 1 Diabetes Mellitus. Indian Pediatr 2018; 55:524-525. [PMID: 29978825] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Flash glucose monitoring using Free Style Libre Pro (FSLP) was undertaken among fifteen diabetic children. Data revealed high glycaemic variability, Time in Target Range (TIR) to be 27% and 12% of time in hypoglycaemia. Sensor insertion and retention were problematic in 33%. Though user friendly, sensors may need an additional adhesive plaster for retention.
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Affiliation(s)
- Sridevi A Naaraayan
- Department of Pediatrics, Institute of Child Health and Hospital for Children, Egmore, Chennnai, India.
| | - Poovazhagi Varadharajan
- Department of Pediatrics, Government Medical College, Omandurar Government Estate, Triplicane, Chennnai, India
| | | | - Rema Chandramohan
- Department of Pediatrics, Institute of Child Health and Hospital for Children, Egmore, Chennnai, India
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Ravikumar M, Ganesh V, Shkir M, Chandramohan R, Arun Kumar KD, Valanarasu S, Kathalingam A, AlFaify S. Fabrication of Eu doped CdO [Al/Eu-nCdO/p-Si/Al] photodiodes by perfume atomizer based spray technique for opto-electronic applications. J Mol Struct 2018. [DOI: 10.1016/j.molstruc.2018.01.095] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Bhavnani SP, Sola S, Adams D, Venkateshvaran A, Dash P, Sengupta PP, Bhavnani S, Sola S, Venkateshvaran A, Adams D, Sengupta PP, Ryan T, Narula J, Thomas J, Lang R, Pellikka P, Choudhary V, Iyer VR, Barooah B, Sola S, Varyani R, Lingan A, Murugan V, Kini P, Venkateshvaran A, Srinivas N, Barooah AC, Subbarao G, Shivakumar C, Subramaniyan M, Sengupta SP, Bansal M, Rahaman A, Patil VN, Kumar NR, Gahlot MY, Damani IM, Gulati R, Joshi SS, Dubey S, Krupa J, Irfan S, Vidhyakar R, Bidarkar N, Shantesh B, Chavan SS, Chandramohan R, Kumar V, Tirkey S, Prasad G, Lakshmana SS, Malkar RM, Manjunath V, Kumar Reddy K, Ramesha L, Kumbhalkar S, Thadlani JA, Basha TN, Hafeez SA, Leelavathi V, Mathews R, Daubert M, Cleve J, Burdulis E, Fauss N, Lammertin G, Patel B, Petrovets E, Shah D, Thurmond K, Tomberlin D, Umamaheswar H, Kadakia A. A Randomized Trial of Pocket-Echocardiography Integrated Mobile Health Device Assessments in Modern Structural Heart Disease Clinics. JACC Cardiovasc Imaging 2018; 11:546-557. [DOI: 10.1016/j.jcmg.2017.06.019] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Revised: 06/19/2017] [Accepted: 06/19/2017] [Indexed: 12/14/2022]
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Prakashbabu D, Ramalingam HB, Hari Krishna R, Nagabhushana BM, Chandramohan R, Shivakumara C, Thirumalai J, Thomas T. Charge compensation assisted enhancement of photoluminescence in combustion derived Li + co-doped cubic ZrO 2:Eu 3+ nanophosphors. Phys Chem Chem Phys 2018; 18:29447-29457. [PMID: 27738691 DOI: 10.1039/c6cp04633a] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Red light emitting cubic Zr0.99Eu0.01O2:Li+ (0-9 mol%) nanoparticles are synthesized by a low temperature, self-propagating solution combustion method using oxalyl di-hydrazide (ODH) as fuel. In this study, we report systematic investigation of the effect of lithium ion (Li+) concentration on the structural properties and the photoluminescence of zirconia. With increasing lithium concentration, the crystallinity of the samples increases and the lattice strain decreases. The higher crystallinity is likely due to charge compensation achieved by replacing one Zr4+ ion by a Eu3+ and a Li+ ion. Scanning electron micrographs (SEM) reveal a mesoporous structure characteristic of combustion derived nanomaterials. Photoluminescence (PL) spectra show that the intensity of the red emission (606 nm) is highly dependent on Li+ ion concentration. Furthermore there is a promising enhancement in the associated lifetime. Upon Li+ doping, the PL intensity of the samples is found to increase by two fold compared to the undoped sample. Variation of PL intensity with Li+ concentration is attributed to the differences in probability of non-radiative recombination (relaxing). Intensity parameters (Ω2, Ω) and radiative properties such as transition rates (A), branching ratios (β), stimulated emission cross-section (σe), gain bandwidth (σe × Δλeff) and optical gain (σe × τ) are calculated using the Judd-Ofelt theory. The calculated values suggest that in optimally co-doped samples, in addition to improved crystallinity and charge compensation, the lowering of Eu3+ site symmetry and the increase in the covalency of Eu-O bonding due to interstitial Li are responsible for the observed enhancement in PL intensity.
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Affiliation(s)
- D Prakashbabu
- Department of Physics, Bharathiar University, Coimbatore - 641 046, India and School of Physics, Reva University, Bangalore - 560 064, India
| | - H B Ramalingam
- Department of Physics, Government Arts College, Udumalpet - 642 126, India.
| | - R Hari Krishna
- Department of Chemistry, M.S. Ramaiah Institute of Technology, Bangalore - 560 054, India.
| | - B M Nagabhushana
- Department of Chemistry, M.S. Ramaiah Institute of Technology, Bangalore - 560 054, India.
| | - R Chandramohan
- Department of Physics, Sevugan Annamalai College, Devakottai-630303, India
| | - C Shivakumara
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore - 560 012, India
| | - J Thirumalai
- Department of Physics, B.S. Abdur Rahman University, Chennai 600048, India
| | - Tiju Thomas
- Department of Metallurgical and Materials Engineering, Indian Institute of Technology, Madras, Chennai 600 036, India
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Ravikumar M, Chandramohan R, Valanarasu S, Manogowri R, Kathalingam A. Substrate temperature dependent opto-electronic properties of perfume atomized CdO thin films. INORG NANO-MET CHEM 2017. [DOI: 10.1080/24701556.2017.1357600] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- M. Ravikumar
- Department of Physics, Arumugam Pillai Seethai Ammal College, Tiruppattur, India
| | - R. Chandramohan
- Department of Physics, Sree Sevugan Annamalai College, Devakottai, India
| | - S. Valanarasu
- PG and Research Department of Physics, Arul Anandar College, Karumathur, India
| | - R. Manogowri
- Jayaraj Annapackiam College for Women, Periyakulam, India
| | - A. Kathalingam
- Millimeter-Wave Innovation Technology Research Center (MINT), Dongguk University, Seoul, Republic of Korea
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Thayyil S, Oliveira V, Lally PJ, Swamy R, Bassett P, Chandrasekaran M, Mondkar J, Mangalabharathi S, Benkappa N, Seeralar A, Shahidullah M, Montaldo P, Herberg J, Manerkar S, Kumaraswami K, Kamalaratnam C, Prakash V, Chandramohan R, Bandya P, Mannan MA, Rodrigo R, Nair M, Ramji S, Shankaran S. Hypothermia for encephalopathy in low and middle-income countries (HELIX): study protocol for a randomised controlled trial. Trials 2017; 18:432. [PMID: 28923118 PMCID: PMC5604260 DOI: 10.1186/s13063-017-2165-3] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2017] [Accepted: 08/29/2017] [Indexed: 11/10/2022] Open
Abstract
Background Therapeutic hypothermia reduces death and disability after moderate or severe neonatal encephalopathy in high-income countries and is used as standard therapy in these settings. However, the safety and efficacy of cooling therapy in low- and middle-income countries (LMICs), where 99% of the disease burden occurs, remains unclear. We will examine whether whole body cooling reduces death or neurodisability at 18–22 months after neonatal encephalopathy, in LMICs. Methods We will randomly allocate 408 term or near-term babies (aged ≤ 6 h) with moderate or severe neonatal encephalopathy admitted to public sector neonatal units in LMIC countries (India, Bangladesh or Sri Lanka), to either usual care alone or whole-body cooling with usual care. Babies allocated to the cooling arm will have core body temperature maintained at 33.5 °C using a servo-controlled cooling device for 72 h, followed by re-warming at 0.5 °C per hour. All babies will have detailed infection screening at the time of recruitment and 3 Telsa cerebral magnetic resonance imaging and spectroscopy at 1–2 weeks after birth. Our primary endpoint is death or moderate or severe disability at the age of 18 months. Discussion Upon completion, HELIX will be the largest cooling trial in neonatal encephalopathy and will provide a definitive answer regarding the safety and efficacy of cooling therapy for neonatal encephalopathy in LMICs. The trial will also provide important data about the influence of co-existent perinatal infection on the efficacy of hypothermic neuroprotection. Trial registration ClinicalTrials.gov, NCT02387385. Registered on 27 February 2015. Electronic supplementary material The online version of this article (doi:10.1186/s13063-017-2165-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Sudhin Thayyil
- Centre for Perinatal Neuroscience, Imperial College London, London, UK.
| | - Vania Oliveira
- Centre for Perinatal Neuroscience, Imperial College London, London, UK
| | - Peter J Lally
- Centre for Perinatal Neuroscience, Imperial College London, London, UK
| | - Ravi Swamy
- Centre for Perinatal Neuroscience, Imperial College London, London, UK
| | - Paul Bassett
- Stats Consultancy, Amersham, Buckinghamshire, UK
| | | | | | | | | | - Arasar Seeralar
- Institute of Obstetrics & Gynecology, Madras Medical College, Chennai, India
| | - Mohammod Shahidullah
- Neonatal Medicine, Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh
| | - Paolo Montaldo
- Centre for Perinatal Neuroscience, Imperial College London, London, UK
| | - Jethro Herberg
- Paediatric Infectious Diseases, Imperial College London, London, UK
| | - Swati Manerkar
- Lokmanya Tilak Municipal Medical College, Sion, Mumbai, India
| | | | | | - Vinayagam Prakash
- Institute of Obstetrics & Gynecology, Madras Medical College, Chennai, India
| | - Rema Chandramohan
- Institute of Child Health, Egmore, Madras Medical College, Chennai, India
| | - Prathik Bandya
- Indira Gandhi Institute of Child health, Bangalore, India
| | | | | | - Mohandas Nair
- Institute of Maternal and Child Health, Government Medical College Calicut, Calicut, India
| | | | - Seetha Shankaran
- Neonatal-Perinatal Medicine, Wayne State University, Detroit, MI, USA
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Ho AL, Dunn L, Sherman EJ, Fury MG, Baxi SS, Chandramohan R, Dogan S, Morris LGT, Cullen GD, Haque S, Sima CS, Ni A, Antonescu CR, Katabi N, Pfister DG. A phase II study of axitinib (AG-013736) in patients with incurable adenoid cystic carcinoma. Ann Oncol 2016; 27:1902-8. [PMID: 27566443 DOI: 10.1093/annonc/mdw287] [Citation(s) in RCA: 66] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Accepted: 07/19/2016] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Recurrent/metastatic adenoid cystic carcinoma (ACC) is an incurable disease with no standard treatments. The majority of ACCs express the oncogenic transcription factor MYB (also c-myb), often in the context of a MYB gene rearrangement. This phase II trial of the tyrosine kinase inhibitor (TKI) axitinib (Pfizer) tested the hypothesis that targeting pathways activated by MYB can be therapeutically effective for ACC. PATIENTS AND METHODS This is a minimax two-stage, phase II trial that enrolled patients with incurable ACC of any primary site. Progressive or symptomatic disease was required. Patients were treated with axitinib 5 mg oral twice daily; dose escalation was allowed. The primary end point was best overall response (BOR). An exploratory analysis correlating biomarkers to drug benefit was conducted, including next-generation sequencing (NGS) in 11 patients. RESULTS Thirty-three patients were registered and evaluable for response. Fifteen patients had the axitinib dose increased. Tumor shrinkage was achieved in 22 (66.7%); 3 (9.1%) had confirmed partial responses. Twenty-five (75.8%) patients had stable disease, 10 of whom had disease stability for >6 months. The median progression-free survival (PFS) was 5.7 months (range 0.92-21.8 months). Grade 3 axitinib-related toxicities included hypertension, oral pain and fatigue. A trend toward superior PFS was noted with the MYB/NFIB rearrangement, although this was not statistically significant. NGS revealed three tumors with 4q12 amplification, producing increased copies of axitinib-targeted genes PDGFR/KDR/KIT. Two 4q12 amplified patients achieved stable disease for >6 months, including one with significant tumor reduction and the longest PFS on study (21.8 months). CONCLUSIONS Although the primary end point was not met, axitinib exhibited clinical activity with tumor shrinkage achieved in the majority of patients with progressive disease before trial enrollment. Analysis of MYB biomarkers and genomic profiling suggests the hypothesis that 4q12 amplified ACCs are a disease subset that benefit from TKI therapy.
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Affiliation(s)
- A L Ho
- Department of Medicine Department of Medicine
| | | | - E J Sherman
- Department of Medicine Department of Medicine
| | - M G Fury
- Department of Medicine Department of Medicine
| | - S S Baxi
- Department of Medicine Department of Medicine
| | | | | | - L G T Morris
- Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York City, USA
| | | | - S Haque
- Department of Radiology Department of Radiology, Weill Cornell Medical College, New York City
| | - C S Sima
- Department of Epidemiology-Biostatistics, Memorial Sloan Kettering Cancer Center, New York City, USA
| | - A Ni
- Department of Epidemiology-Biostatistics, Memorial Sloan Kettering Cancer Center, New York City, USA
| | | | | | - D G Pfister
- Department of Medicine Department of Medicine
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Valanarasu S, Kathaiingam A, Rhee JK, Chandramohan R, Vijayan TA, Karunakaran M. Improved Memory Effect of ZnO Nanorods Embedded in an Insulating Polymethylmethacrylate Layer. J Nanosci Nanotechnol 2015; 15:1416-20. [PMID: 26353665 DOI: 10.1166/jnn.2015.9034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Fabrication and characterization of memory devices using ZnO nanorod layer grown by chemical-bath method is reported. The fabricated memory device was found exhibit electrical bistability and nonvolatile memory phenomenon. An additional Polymethylmethacrylate (PMMA) polymer layer coated on ITO substrate prior to nanorod deposition has been found improve the LRS/HRS ratio of the device. The current-voltage characteristics of the memory devices are discussed in terms of formation and rupture of conductive filaments. The devices have shown consistent electrical bistable behavior even for 10(5) resistance-switching cycles. This hybrid ITO/PMMA-ZnO NRs/Al device has potential applications in the field of bistable random access memories.
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Valanarasu S, Dhanasekaran V, Karunakaran M, Chandramohan R, Mahalingam T. Role of solution pH on the microstructural properties of spin coated cobalt oxide thin films. J Nanosci Nanotechnol 2014; 14:4286-4291. [PMID: 24738384 DOI: 10.1166/jnn.2014.8284] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Cobalt Oxide (Co3o4) thin films have been successfully coated onto glass substrates at various solution pH by sol-gel spin coating technique. The film thickness was estimated using weight gain method and it revealed that the film thickness increased with solution pH values. The prepared film structural, morphological, optical and electrical properties were studied using X-ray diffraction (XRD), scanning electron microscope (SEM), UV-Vis-NIR spectrophotometer and Vander Pau method, respectively. The structure of the films were found to be face centered cubic with preferential orientation along (311) plane. X-ray line profile analysis was used to evaluate the micro structural parameters such as crystallite size, micro strain, dislocation density and stacking fault probability. The crystallite size values are increased with increase of solution pH values and maximum value of crystallite is estimated at 40.8 nm at solution pH 8 +/- 0.1. Morphological results showed that the pH of the solution has a marked effect on morphology of the Co3O4 thin films. The optical studies revealed that the band gap can be tailored between 2.16 to 2.31 eV by altering pH. The thin film formed at a solution pH 7 is found to have a low resistivity and high mobility. The electrical resistivity (p), carrier concentration (n) and mobility (micro) values are 0.1 x 10(3) omega x cm, 8.9 cm2 gammas(-1) and 6.6 x 10(14) cm(-3), respectively for Co3O4 thin film prepared at solution pH 7 +/- 0.1. EDAX studies showed that the cobalt content increased and the oxygen content decreased with increase of pH.
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Prakashbabu D, Hari Krishna R, Nagabhushana BM, Nagabhushana H, Shivakumara C, Chakradar RPS, Ramalingam HB, Sharma SC, Chandramohan R. Low temperature synthesis of pure cubic ZrO2 nanopowder: structural and luminescence studies. Spectrochim Acta A Mol Biomol Spectrosc 2014; 122:216-222. [PMID: 24317256 DOI: 10.1016/j.saa.2013.11.043] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2013] [Revised: 10/28/2013] [Accepted: 11/10/2013] [Indexed: 06/02/2023]
Abstract
Pure cubic zirconia (ZrO2) nanopowder is prepared for the first time by simple low temperature solution combustion method without calcination. The product is characterized by Powder X-ray Diffraction (PXRD), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Fourier Transform Infra Red spectroscopy (FTIR) and Ultraviolet-Visible spectroscopy (UV-Vis). The PXRD showed the formation of pure stable cubic ZrO2 nanopowders with average crystallite size ranging from 6 to 12 nm. The lattice parameters were calculated from Rietveld refinement method. SEM micrograph shows fluffy, mesoporous, agglomerated particles with large number of voids. TEM micrograph shows honey comb like arrangement of particles with particle size ∼10 nm. The PL emission spectrum excited at 210 nm and 240 nm consists of intense bands centered at ∼365 and ∼390 nm. Both the samples show shoulder peak at ∼420 nm, along with four weak emission bands at ∼484, ∼528, ∼614 and ∼726 nm. TL studies were carried out pre-irradiating samples with γ-rays ranging from 1 to 5 KGy at room temperature. A well resolved glow peak at 377 °C is recorded which can be ascribed to deep traps. With increase in γ radiation there is linear increase in TL intensity which shows the possible use of ZrO2 as dosimetric material.
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Affiliation(s)
- D Prakashbabu
- Bharathiar University, Coimbatore 641 046, India; Department of Physics, Government Arts College, Udumalpet 642 126, India.
| | - R Hari Krishna
- Department of Chemistry, M.S. Ramaiah Institute of Technology, Bangalore 560 054, India.
| | - B M Nagabhushana
- Department of Chemistry, M.S. Ramaiah Institute of Technology, Bangalore 560 054, India
| | - H Nagabhushana
- C.N.R. Rao Center for Nano Research, Tumkur University, Tumkur 572 103, India
| | - C Shivakumara
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560 012, India
| | - R P S Chakradar
- National Aerospace Laboratory (CSIR), Bangalore 560 017, India
| | - H B Ramalingam
- Department of Physics, Government Arts College, Udumalpet 642 126, India
| | - S C Sharma
- Department of Mechanical Engineering, B.M.S. Institute of Technology, Bangalore 560 064, India
| | - R Chandramohan
- Department of Physics, Sevugan Annamalai College, Devakottai 630 303, India
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Dhanasekaran V, Soundaram N, Kim SI, Chandramohan R, Mantha S, Saravanakumar S, Mahalingam T. Optical, electrical and microstructural studies of monoclinic CuO nanostructures synthesized by a sol–gel route. NEW J CHEM 2014. [DOI: 10.1039/c4nj00084f] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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21
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Valanarasu S, Kulandaisamy I, Kathalingam A, Rhee JK, Vijayan TA, Chandramohan R. High-performance memory device using graphene oxide flakes sandwiched polymethylmethacrylate layers. J Nanosci Nanotechnol 2013; 13:6755-6759. [PMID: 24245139 DOI: 10.1166/jnn.2013.7740] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Organic bistable devices (OBDs) using graphene oxide (GO) flakes sandwiched polymethylmethacrylate (PMMA) films were fabricated. These devices exhibited two accessible conducting states, that is, a low-conductivity (OFF) state and a high-conductivity (ON) state. The devices can be switched to ON state under a negative electrical sweep; it can also be reset to the initial OFF state by a reverse (positive) electrical sweep. Detailed I-V measurements have shown that in ITO/PMMA/GO/PMMA/Al sandwiches the resistive switching originates from the formation and rupture of conducting filaments. The ON/OFF ratio of the OBDs was approximately 5 x 10(3), reproducibility of more than 10(5) cycles, and retention time of 10(4) s. These properties show that the device is promising for high-density, low-cost memory application.
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Affiliation(s)
- S Valanarasu
- Department of Physics, Arul Anandar College, Karumathur, Madurai 625514, India
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22
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Valanarasu S, Dhanasekaran V, Chandramohan R, Kulandaisamy I, Sakthivelu A, Mahalingam T. Variation of microstructural and optical properties in SILAR grown ZnO thin films by thermal treatment. J Nanosci Nanotechnol 2013; 13:5613-5619. [PMID: 23882804 DOI: 10.1166/jnn.2013.7473] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The influence of thermal treatment on the structural and morphological properties of the ZnO films deposited by double dip Successive ionic layer by adsorption reaction is presented. The effect of annealing temperature and time in air ambient is presented in detail. The deposited films were annealed from 200 to 400 degrees C in air and the structural properties were determined as a function of annealing temperature by XRD. The studies revealed that films were exhibiting preferential orientation along (002) plane. The other structural parameters like the crystallite size (D), micro strain (epsilon), dislocation density (delta) and stacking fault (alpha) of as-deposited and annealed ZnO films were evaluated and reported. The optical properties were also studied and the band gap of the ZnO thins films varied from 3.27 to 3.04 eV with the annealing temperature. SEM studies revealed that the hexagonal shaped grains with uniformly distributed morphology in annealed ZnO thin films. It has been envisaged using EDX analysis that the near stoichiometric composition of the film can be attained by thermal treatment during which microstructural changes do occur.
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Affiliation(s)
- S Valanarasu
- Department of Physics, Arul Anandar College, Karumathur 625514, India
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Affiliation(s)
- R Chandramohan
- Department of Medicine, Jawaharlal Institute of Postgraduate Medical Education and Research (JIPMER), Puducherry, India.
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Vinod KV, Chandramohan R, Dutta TK, Rajesh NG, Basu D. Type 2 lepra reaction as a cause of pyrexia of unknown origin. J Assoc Physicians India 2012; 60:70-72. [PMID: 23029751] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Leprosy, a commonly encountered disease, can rarely present as a reactional state de novo with fever as the main presenting feature. Here we describe an uncommon presentation of leprosy [with type 2 lepra reaction] as pyrexia of unknown origin with prominent rheumatologic manifestations [acute polyarthritis], renal involvement and generalized lymphadenopathy with rare presentation of type 2 lepra reaction without the classic skin lesions of erythema nodosum leprosum, occurring in a treatment naive patient without prior history of leprosy.
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Affiliation(s)
- K V Vinod
- Dept. of General Medicine, JIPMER, Dhanvantarinagar, Puducherry-605006
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Vijayan C, Soundararajan N, Chandramohan R, Dhanasekaran V, Sundaram K, Neyvasagam K, Mahalingam T. Morphological properties of Ag₂SeTe nano thin films prepared by thermal evaporation. J Microsc 2011; 243:267-72. [PMID: 21756251 DOI: 10.1111/j.1365-2818.2011.03500.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Semiconducting silver selenide telluride (Ag₂SeTe) thin films were prepared with different thicknesses onto glass substrates at room temperature using thermal evaporation technique. The structural properties were determined as a function of thickness by X-ray diffraction exhibiting no preferential orientation along any plane; however, the films are found to have peaks corresponding to mixed phase. The morphology of these films was studied using scanning electron microscope and atomic force microscopy respectively, and is reported. The morphological properties are found to be very sensitive to the thin film thickness. The composition of the films is also estimated using energy dispersive analysis using X-rays and are also reported.
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Affiliation(s)
- C Vijayan
- Department of Physics, N.M.S.S. Vellaichamynadar College, Madurai, India
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Dhanasekaran V, Mahalingam T, Chandramohan R. Morphology selection for cupric oxide thin films by electrodeposition. Microsc Res Tech 2011; 74:980-3. [PMID: 21484941 DOI: 10.1002/jemt.20984] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2010] [Accepted: 12/03/2010] [Indexed: 11/08/2022]
Abstract
Polycrystalline cupric oxide thin films were deposited using alkaline solution bath employing cathodic electrodeposition method. The thin films were electrodeposited at various solution pH. The surface morphology and elemental analyzes of the films were studied using scanning electron microscopy (SEM) and energy dispersive X-ray analysis, respectively. SEM studies revealed that the surface morphology could be tailored suitably by adjusting the pH value during deposition. Mesh average on multiple lattice mode atomic force microscopy image was obtained and reported.
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Affiliation(s)
- V Dhanasekaran
- Department of Physics, Alagappa University, Karaikudi 630003, India
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Chandramohan R, Thirumalai J, Vijayan TA, Valanarasu S, Vizhian SE, Srikanth M, Swaminathan V. Nanocrystalline Mg Doped ZnO Dilute Magnetic Semiconductor Prepared by Chemical Route. ACTA ACUST UNITED AC 2010. [DOI: 10.1166/asl.2010.1129] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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28
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Lakshmanraj L, Gurusamy A, Gobinath MB, Chandramohan R. Studies on the biosorption of hexavalent chromium from aqueous solutions by using boiled mucilaginous seeds of Ocimum americanum. J Hazard Mater 2009; 169:1141-5. [PMID: 19406568 DOI: 10.1016/j.jhazmat.2009.03.022] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2007] [Revised: 02/27/2009] [Accepted: 03/04/2009] [Indexed: 05/12/2023]
Abstract
Investigations were carried out to study the chromium removal efficiency of boiled mucilaginous seeds of Ocimum americanum. Batch experiments were conducted to study the biosorption kinetics of chromium removal for the concentrations 10mg/L, 20mg/L and 40 mg/L of chromium(VI) solutions. The biosorbent dosage was 8 g dry seeds/L. The toxic hexavalent chromium was reduced to less toxic chromium(III) in the presence of seeds and the reduced chromium was adsorbed on the mucilage of seeds. Both the chromium(VI) and chromium(III) were present in the aqueous phase. The optimum chromium reduction and adsorption was observed at the pH value 1.5. The biosorption data fitted well with Langmuir isotherm. The biosorption capacity calculated from the Langmuir isotherm was q=32 mg chromium(III)/g of dry seeds. The continuous column study was also carried out at the flow rate of 27 mL/h for the initial concentration 25mg/L of chromium(VI) feed solution using a packed bed column filled with boiled mucilaginous seeds. The maximum reduction of chromium(VI) to chromium(III) in the packed bed was 80%. The percentage removal of reduced chromium from the aqueous solution was 56.25%. This value was maintained constant until 0.52 L of chromium(VI) solution was pumped through the packed bed column. Thus the naturally immobilized polysaccharides on the seeds mimic the microbial polysaccharides in terms of their ability to adsorb heavy metals with an added advantage of making the immobilization step unnecessary which is a major cost factor of the metal removal process when microbial exopolysaccharides used. The uniform size and spherical shape of swollen seeds give an additional advantage to use them in a packed bed column for continuous removal of chromium(VI) from aqueous solutions.
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Affiliation(s)
- Levankumar Lakshmanraj
- Department of Biotechnology, PSG College of Technology, Peelamedu, Coimbatore 641004, India.
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Thirumalai J, Chandramohan R, Divakar R, Mohandas E, Sekar M, Parameswaran P. Eu(3+) doped gadolinium oxysulfide (Gd(2)O(2)S) nanostructures-synthesis and optical and electronic properties. Nanotechnology 2008; 19:395703. [PMID: 21832604 DOI: 10.1088/0957-4484/19/39/395703] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
One-dimensional Eu(3+) doped gadolinium oxysulfide (Gd(2)O(2)S:Eu(3+)) nanotubes/nanorods have been synthesized via precursors of Gd(OH)(3) nanostructures using a hydrothermal technique. The blue-shifts in the optical spectra for the Gd(2)O(2)S:Eu(3+) system corresponding to the fundamental absorption and Eu(3+)-X(2-) ligand (X = O/S) charge transfer bands (CTBs) are significant (∼0.22-0.36 eV) with respect to the bulk counterpart. The nanotubes are good candidates for investigating the size-induced electrical and optical properties of functional oxysulfides. In order to identify the origin and nature of the electronic transitions observed in the visible region, optical and photo-induced impedance measurements have been extended to the nanotubes in this report.
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Affiliation(s)
- J Thirumalai
- Department of Physics, Sree Sevugan Annamalai College, Devakottai-630 033 (TN), India
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Kumar K, Ramamoorthy K, Chandramohan R, Sankaranarayanan K. A novel growth method for ZnAl2O4 single crystals. Cryst Res Technol 2006. [DOI: 10.1002/crat.200510562] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Chandramohan R, Sanjeeviraja C, Mahalingam T. Preparation of Zinc Selenide Thin Films by Electrodeposition Technique for Solar Cell Applications. ACTA ACUST UNITED AC 1997. [DOI: 10.1002/1521-396x(199710)163:23.0.co;2-3] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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