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Kirolikar S, Prasannan P, Raghuram GV, Pancholi N, Saha T, Tidke P, Chaudhari P, Shaikh A, Rane B, Pandey R, Wani H, Khare NK, Siddiqui S, D'souza J, Prasad R, Shinde S, Parab S, Nair NK, Pal K, Mittra I. Prevention of radiation-induced bystander effects by agents that inactivate cell-free chromatin released from irradiated dying cells. Cell Death Dis 2018; 9:1142. [PMID: 30442925 PMCID: PMC6238009 DOI: 10.1038/s41419-018-1181-x] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Revised: 10/20/2018] [Accepted: 10/22/2018] [Indexed: 12/15/2022]
Abstract
Radiation-induced bystander effect (RIBE) is a poorly understood phenomenon wherein non-targeted cells exhibit effects of radiation. We have reported that cell-free chromatin (cfCh) particles that are released from dying cells can integrate into genomes of surrounding healthy cells to induce DNA damage and inflammation. This raised the possibility that RIBE might be induced by cfCh released from irradiated dying cells. When conditioned media from BrdU-labeled irradiated cells were passed through filters of pore size 0.22 µm and incubated with unexposed cells, BrdU-labeled cfCh particles could be seen to readily enter their nuclei to activate H2AX, active Caspase-3, NFκB, and IL-6. A direct relationship was observed with respect to activation of RIBE biomarkers and radiation dose in the range of 0.1-0 Gy. We confirmed by FISH and cytogenetic analysis that cfCh had stably integrated into chromosomes of bystander cells and had led to extensive chromosomal instability. The above RIBE effects could be abrogated when conditioned media were pre-treated with agents that inactivate cfCh, namely, anti-histone antibody complexed nanoparticles (CNPs), DNase I and a novel DNA degrading agent Resveratrol-copper (R-Cu). Lower hemi-body irradiation with γ-rays (0.1-50 Gy) led to activation of H2AX, active Caspase-3, NFκB, and IL-6 in brain cells in a dose-dependent manner. Activation of these RIBE biomarkers could be abrogated by concurrent treatment with CNPs, DNase I and R-Cu indicating that activation of RIBE was not due to radiation scatter to the brain. RIBE activation was seen even when mini-beam radiation was delivered to the umbilical region of mice wherein radiation scatter to brain was negligible and could be abrogated by cfCh inactivating agents. These results indicate that cfCh released from radiation-induced dying cells are activators of RIBE and that it can be prevented by treatment with appropriate cfCh inactivating agents.
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Affiliation(s)
- Saurabh Kirolikar
- Translational Research Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Navi-Mumbai, 410210, India
| | - Preeti Prasannan
- Translational Research Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Navi-Mumbai, 410210, India
| | - Gorantla V Raghuram
- Translational Research Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Navi-Mumbai, 410210, India
| | - Namrata Pancholi
- Translational Research Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Navi-Mumbai, 410210, India
| | - Tannishtha Saha
- Translational Research Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Navi-Mumbai, 410210, India
| | - Pritishkumar Tidke
- Translational Research Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Navi-Mumbai, 410210, India
| | - Pradip Chaudhari
- Comparative Oncology Program and Small Animal Imaging Facility, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Navi-Mumbai, 410210, India
| | - Alfina Shaikh
- Translational Research Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Navi-Mumbai, 410210, India
| | - Bhagyeshri Rane
- Translational Research Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Navi-Mumbai, 410210, India
| | - Richa Pandey
- Translational Research Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Navi-Mumbai, 410210, India
| | - Harshada Wani
- Translational Research Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Navi-Mumbai, 410210, India
| | - Naveen K Khare
- Translational Research Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Navi-Mumbai, 410210, India
| | - Sophiya Siddiqui
- Translational Research Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Navi-Mumbai, 410210, India
| | - Jenevieve D'souza
- Translational Research Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Navi-Mumbai, 410210, India
| | - Ratnam Prasad
- Translational Research Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Navi-Mumbai, 410210, India
| | - Sushma Shinde
- Translational Research Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Navi-Mumbai, 410210, India
| | - Sailee Parab
- Translational Research Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Navi-Mumbai, 410210, India
| | - Naveen K Nair
- Translational Research Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Navi-Mumbai, 410210, India
| | - Kavita Pal
- Translational Research Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Navi-Mumbai, 410210, India
| | - Indraneel Mittra
- Translational Research Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Navi-Mumbai, 410210, India.
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Mittra I, Pal K, Pancholi N, Shaikh A, Rane B, Tidke P, Kirolikar S, Khare NK, Agrawal K, Nagare H, Nair NK. Prevention of chemotherapy toxicity by agents that neutralize or degrade cell-free chromatin. Ann Oncol 2018; 28:2119-2127. [PMID: 28911066 DOI: 10.1093/annonc/mdx318] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Background Toxicity associated with chemotherapy is a major therapeutic challenge and is caused by chemotherapy-induced DNA damage and inflammation. We have recently reported that cell-free chromatin (cfCh) fragments released from dying cells can readily enter into healthy cells of the body to integrate into their genomes and induce DNA double-strand breaks, apoptosis and inflammation in them. We hypothesized that much of the toxicity of chemotherapy might be due to release of large quantities of cfCh from dying cells that could trigger an exaggerated DNA damage, apoptotic and inflammatory response in healthy cells over and above that caused by the drugs themselves. Methods We tested this hypothesis by administering cfCh neutralizing/degrading agents namely, anti-histone antibody complexed nanoparticles, DNase I and a novel DNA degrading agent-Resveratrol-Cu concurrently with five different chemotherapeutic agents to examine if chemotherapy-induced toxicity could be minimized. Results We observed (i) significant reduction in chemotherapy-induced surge of cfCh in blood; (ii) significant reduction in chemotherapy-induced surge of inflammatory cytokines CRP, IL-6, IFNγ and TNFα in blood; (iii) abolition of chemotherapy-induced tissue DNA damage (γH2AX), apoptosis (active caspase-3) and inflammation (NFκB and IL-6) in multiple organs and peripheral blood mononuclear cells; (iv) prevention of prolonged neutropenia following a single injection of adriamycin and (v) significant reduction in death following a lethal dose of adriamycin. Conclusion Our results suggest that toxicity of chemotherapy is caused to a large extent by cfCh released from dying cells and can be prevented by concurrent treatment with cfCh neutralizing/degrading agents.
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Affiliation(s)
- I Mittra
- Translational Research Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Sector 22, Utsav Chowk - CISF Road, Kharghar, Navi Mumbai, Raigad, Maharashtra 410210, India
| | - K Pal
- Translational Research Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Sector 22, Utsav Chowk - CISF Road, Kharghar, Navi Mumbai, Raigad, Maharashtra 410210, India
| | - N Pancholi
- Translational Research Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Sector 22, Utsav Chowk - CISF Road, Kharghar, Navi Mumbai, Raigad, Maharashtra 410210, India
| | - A Shaikh
- Translational Research Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Sector 22, Utsav Chowk - CISF Road, Kharghar, Navi Mumbai, Raigad, Maharashtra 410210, India
| | - B Rane
- Translational Research Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Sector 22, Utsav Chowk - CISF Road, Kharghar, Navi Mumbai, Raigad, Maharashtra 410210, India
| | - P Tidke
- Translational Research Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Sector 22, Utsav Chowk - CISF Road, Kharghar, Navi Mumbai, Raigad, Maharashtra 410210, India
| | - S Kirolikar
- Translational Research Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Sector 22, Utsav Chowk - CISF Road, Kharghar, Navi Mumbai, Raigad, Maharashtra 410210, India
| | - N K Khare
- Translational Research Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Sector 22, Utsav Chowk - CISF Road, Kharghar, Navi Mumbai, Raigad, Maharashtra 410210, India
| | - K Agrawal
- Translational Research Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Sector 22, Utsav Chowk - CISF Road, Kharghar, Navi Mumbai, Raigad, Maharashtra 410210, India
| | - H Nagare
- Translational Research Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Sector 22, Utsav Chowk - CISF Road, Kharghar, Navi Mumbai, Raigad, Maharashtra 410210, India
| | - N K Nair
- Translational Research Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Sector 22, Utsav Chowk - CISF Road, Kharghar, Navi Mumbai, Raigad, Maharashtra 410210, India
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Teesson M, Newton NC, Slade T, Carragher N, Barrett EL, Champion KE, Kelly EV, Nair NK, Stapinski LA, Conrod PJ. Combined universal and selective prevention for adolescent alcohol use: a cluster randomized controlled trial. Psychol Med 2017; 47:1761-1770. [PMID: 28222825 DOI: 10.1017/s0033291717000198] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
BACKGROUND No existing models of alcohol prevention concurrently adopt universal and selective approaches. This study aims to evaluate the first combined universal and selective approach to alcohol prevention. METHOD A total of 26 Australian schools with 2190 students (mean age: 13.3 years) were randomized to receive: universal prevention (Climate Schools); selective prevention (Preventure); combined prevention (Climate Schools and Preventure; CAP); or health education as usual (control). Primary outcomes were alcohol use, binge drinking and alcohol-related harms at 6, 12 and 24 months. RESULTS Climate, Preventure and CAP students demonstrated significantly lower growth in their likelihood to drink and binge drink, relative to controls over 24 months. Preventure students displayed significantly lower growth in their likelihood to experience alcohol harms, relative to controls. While adolescents in both the CAP and Climate groups demonstrated slower growth in drinking compared with adolescents in the control group over the 2-year study period, CAP adolescents demonstrated faster growth in drinking compared with Climate adolescents. CONCLUSIONS Findings support universal, selective and combined approaches to alcohol prevention. Particularly novel are the findings of no advantage of the combined approach over universal or selective prevention alone.
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Affiliation(s)
- M Teesson
- NHMRC Centre of Research Excellence in Mental Health and Substance Use (CREMS), National Drug and Alcohol Research Centre, University of New South Wales,Sydney, NSW,Australia
| | - N C Newton
- NHMRC Centre of Research Excellence in Mental Health and Substance Use (CREMS), National Drug and Alcohol Research Centre, University of New South Wales,Sydney, NSW,Australia
| | - T Slade
- NHMRC Centre of Research Excellence in Mental Health and Substance Use (CREMS), National Drug and Alcohol Research Centre, University of New South Wales,Sydney, NSW,Australia
| | - N Carragher
- NHMRC Centre of Research Excellence in Mental Health and Substance Use (CREMS), National Drug and Alcohol Research Centre, University of New South Wales,Sydney, NSW,Australia
| | - E L Barrett
- NHMRC Centre of Research Excellence in Mental Health and Substance Use (CREMS), National Drug and Alcohol Research Centre, University of New South Wales,Sydney, NSW,Australia
| | - K E Champion
- NHMRC Centre of Research Excellence in Mental Health and Substance Use (CREMS), National Drug and Alcohol Research Centre, University of New South Wales,Sydney, NSW,Australia
| | - E V Kelly
- NHMRC Centre of Research Excellence in Mental Health and Substance Use (CREMS), National Drug and Alcohol Research Centre, University of New South Wales,Sydney, NSW,Australia
| | - N K Nair
- NHMRC Centre of Research Excellence in Mental Health and Substance Use (CREMS), National Drug and Alcohol Research Centre, University of New South Wales,Sydney, NSW,Australia
| | - L A Stapinski
- NHMRC Centre of Research Excellence in Mental Health and Substance Use (CREMS), National Drug and Alcohol Research Centre, University of New South Wales,Sydney, NSW,Australia
| | - P J Conrod
- Department of Psychiatry,Université de Montréal,Montréal,Quebec,Canada
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Mittra I, Samant U, Sharma S, Raghuram GV, Saha T, Tidke P, Pancholi N, Gupta D, Prasannan P, Gaikwad A, Gardi N, Chaubal R, Upadhyay P, Pal K, Rane B, Shaikh A, Salunkhe S, Dutt S, Mishra PK, Khare NK, Nair NK, Dutt A. Cell-free chromatin from dying cancer cells integrate into genomes of bystander healthy cells to induce DNA damage and inflammation. Cell Death Discov 2017; 3:17015. [PMID: 28580170 PMCID: PMC5447133 DOI: 10.1038/cddiscovery.2017.15] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Revised: 01/10/2017] [Accepted: 02/05/2017] [Indexed: 02/08/2023] Open
Abstract
Bystander cells of the tumor microenvironment show evidence of DNA damage and inflammation that can lead to their oncogenic transformation. Mediator(s) of cell-cell communication that brings about these pro-oncogenic pathologies has not been identified. We show here that cell-free chromatin (cfCh) released from dying cancer cells are the key mediators that trigger both DNA damage and inflammation in the surrounding healthy cells. When dying human cancer cells were cultured along with NIH3T3 mouse fibroblast cells, numerous cfCh emerged from them and rapidly entered into nuclei of bystander NIH3T3 cells to integrate into their genomes. This led to activation of H2AX and inflammatory cytokines NFκB, IL-6, TNFα and IFNγ. Genomic integration of cfCh triggered global deregulation of transcription and upregulation of pathways related to phagocytosis, DNA damage and inflammation. None of these activities were observed when living cancer cells were co-cultivated with NIH3T3 cells. However, upon intravenous injection into mice, both dead and live cells were found to be active. Living cancer cells are known to undergo extensive cell death when injected intravenously, and we observed that cfCh emerging from both types of cells integrated into genomes of cells of distant organs and induced DNA damage and inflammation. γH2AX and NFκB were frequently co-expressed in the same cells suggesting that DNA damage and inflammation are closely linked pathologies. As concurrent DNA damage and inflammation is a potent stimulus for oncogenic transformation, our results suggest that cfCh from dying cancer cells can transform cells of the microenvironment both locally and in distant organs providing a novel mechanism of tumor invasion and metastasis. The afore-described pro-oncogenic pathologies could be abrogated by concurrent treatment with chromatin neutralizing/degrading agents suggesting therapeutic possibilities.
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Affiliation(s)
- Indraneel Mittra
- Translational Research Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Mumbai 410210, India
- Division of Laboratory Medicine, Tata Memorial Hospital, Tata Memorial Centre, Mumbai 400012, India
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| | - Urmila Samant
- Division of Laboratory Medicine, Tata Memorial Hospital, Tata Memorial Centre, Mumbai 400012, India
| | - Suvarna Sharma
- Division of Laboratory Medicine, Tata Memorial Hospital, Tata Memorial Centre, Mumbai 400012, India
| | - Gorantla V Raghuram
- Translational Research Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Mumbai 410210, India
| | - Tannistha Saha
- Translational Research Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Mumbai 410210, India
| | - Pritishkumar Tidke
- Translational Research Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Mumbai 410210, India
| | - Namrata Pancholi
- Translational Research Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Mumbai 410210, India
| | - Deepika Gupta
- Translational Research Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Mumbai 410210, India
| | - Preeti Prasannan
- Translational Research Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Mumbai 410210, India
| | - Ashwini Gaikwad
- Translational Research Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Mumbai 410210, India
| | - Nilesh Gardi
- Integrated Cancer Genomics Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Mumbai 410210, India
- Homi Bhabha National Institute, Training School Complex, Anushakti Nagar, Mumbai 410210, India
| | - Rohan Chaubal
- Integrated Cancer Genomics Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Mumbai 410210, India
- Homi Bhabha National Institute, Training School Complex, Anushakti Nagar, Mumbai 410210, India
| | - Pawan Upadhyay
- Integrated Cancer Genomics Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Mumbai 410210, India
- Homi Bhabha National Institute, Training School Complex, Anushakti Nagar, Mumbai 410210, India
| | - Kavita Pal
- Translational Research Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Mumbai 410210, India
| | - Bhagyeshri Rane
- Translational Research Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Mumbai 410210, India
| | - Alfina Shaikh
- Translational Research Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Mumbai 410210, India
| | - Sameer Salunkhe
- Homi Bhabha National Institute, Training School Complex, Anushakti Nagar, Mumbai 410210, India
- DNA Repair and Chromatin Biology Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Mumbai 410210, India
| | - Shilpee Dutt
- Homi Bhabha National Institute, Training School Complex, Anushakti Nagar, Mumbai 410210, India
- DNA Repair and Chromatin Biology Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Mumbai 410210, India
| | - Pradyumna K Mishra
- Translational Research Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Mumbai 410210, India
| | - Naveen K Khare
- Translational Research Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Mumbai 410210, India
| | - Naveen K Nair
- Translational Research Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Mumbai 410210, India
| | - Amit Dutt
- Integrated Cancer Genomics Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Mumbai 410210, India
- Homi Bhabha National Institute, Training School Complex, Anushakti Nagar, Mumbai 410210, India
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Carragher N, Teesson M, Sunderland M, Newton NC, Krueger RF, Conrod PJ, Barrett EL, Champion KE, Nair NK, Slade T. The structure of adolescent psychopathology: a symptom-level analysis. Psychol Med 2016; 46:981-994. [PMID: 26620582 DOI: 10.1017/s0033291715002470] [Citation(s) in RCA: 70] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
BACKGROUND Most empirical studies into the covariance structure of psychopathology have been confined to adults. This work is not developmentally informed as the meaning, age-of-onset, persistence and expression of disorders differ across the lifespan. This study investigates the underlying structure of adolescent psychopathology and associations between the psychopathological dimensions and sex and personality risk profiles for substance misuse and mental health problems. METHOD This study analyzed data from 2175 adolescents aged 13.3 years. Five dimensional models were tested using confirmatory factor analysis and the external validity was examined using a multiple-indicators multiple-causes model. RESULTS A modified bifactor model, with three correlated specific factors (internalizing, externalizing, thought disorder) and one general psychopathology factor, provided the best fit to the data. Females reported higher mean levels of internalizing, and males reported higher mean levels of externalizing. No significant sex differences emerged in liability to thought disorder or general psychopathology. Liability to internalizing, externalizing, thought disorder and general psychopathology was characterized by a number of differences in personality profiles. CONCLUSIONS This study is the first to identify a bifactor model including a specific thought disorder factor. The findings highlight the utility of transdiagnostic treatment approaches and the importance of restructuring psychopathology in an empirically based manner.
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Affiliation(s)
- N Carragher
- National Drug and Alcohol Research Centre,University of New South Wales,Sydney,Australia
| | - M Teesson
- National Drug and Alcohol Research Centre,University of New South Wales,Sydney,Australia
| | - M Sunderland
- National Drug and Alcohol Research Centre,University of New South Wales,Sydney,Australia
| | - N C Newton
- National Drug and Alcohol Research Centre,University of New South Wales,Sydney,Australia
| | - R F Krueger
- Department of Psychology,University of Minnesota,MN,USA
| | - P J Conrod
- Department of Psychiatry,Université de Montréal,Montréal,Canada
| | - E L Barrett
- National Drug and Alcohol Research Centre,University of New South Wales,Sydney,Australia
| | - K E Champion
- National Drug and Alcohol Research Centre,University of New South Wales,Sydney,Australia
| | - N K Nair
- National Drug and Alcohol Research Centre,University of New South Wales,Sydney,Australia
| | - T Slade
- National Drug and Alcohol Research Centre,University of New South Wales,Sydney,Australia
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Subramaniam S, Vohra I, Iyer A, Nair NK, Mittra I. A paradoxical relationship between Resveratrol and copper (II) with respect to degradation of DNA and RNA. F1000Res 2015; 4:1145. [PMID: 27134724 DOI: 10.12688/f1000research.7202.1] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 10/19/2015] [Indexed: 01/24/2023] Open
Abstract
Resveratrol (R), a plant polyphenol, is known to reduce Cu (II) to Cu (I) generating reactive oxygen species that can cleave plasmid DNA. Here we report a surprising observation of a paradoxical relationship between R and Cu whereby plasmid DNA cleaving / degrading activity of R-Cu increased progressively as the ratio of R to Cu was increased i.e., the concentration of Cu was successively reduced with respect to a fixed concentration R. Whereas cleavage of plasmid DNA occurred at low molar ratios of R to Cu, at higher ratios, complete degradation of DNA was achieved. By further increasing the ratio, whereby the concentration of Cu was reduced to very low levels, the DNA degrading activity of R-Cu was lost. This paradoxical relationship is also seen with respect to eukaryotic genomic DNA and RNA. Since R-Cu may have anti-cancer and anti-viral activities, our findings may not only help to improve the therapeutic efficacy of R-Cu but also reduce its toxic side effects with the use of low concentration of Cu.
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Affiliation(s)
- Siddharth Subramaniam
- Translational Research Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Kharghar, Navi-Mumbai, 410210, India
| | - Iqbal Vohra
- Translational Research Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Kharghar, Navi-Mumbai, 410210, India
| | - Aishwarya Iyer
- Translational Research Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Kharghar, Navi-Mumbai, 410210, India
| | - Naveen K Nair
- Translational Research Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Kharghar, Navi-Mumbai, 410210, India
| | - Indraneel Mittra
- Translational Research Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Kharghar, Navi-Mumbai, 410210, India
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Abstract
Resveratrol (R), a plant polyphenol, is known to reduce Cu (II) to Cu (I) generating reactive oxygen species that can cleave plasmid DNA. Here we report a surprising observation of a paradoxical relationship between R and Cu whereby plasmid DNA cleaving / degrading activity of R-Cu increased progressively as the ratio of R to Cu was increased i.e., the concentration of Cu was successively reduced with respect to a fixed concentration R. Whereas cleavage of plasmid DNA occurred at low molar ratios of R to Cu, at higher ratios, complete degradation of DNA was achieved. By further increasing the ratio, whereby the concentration of Cu was reduced to very low levels, the DNA degrading activity of R-Cu was lost. This paradoxical relationship is also seen with respect to eukaryotic genomic DNA and RNA. Since R-Cu may have anti-cancer and anti-viral activities, our findings may not only help to improve the therapeutic efficacy of R-Cu but also reduce its toxic side effects with the use of low concentration of Cu.
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Affiliation(s)
- Siddharth Subramaniam
- Translational Research Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Kharghar, Navi-Mumbai, 410210, India
| | - Iqbal Vohra
- Translational Research Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Kharghar, Navi-Mumbai, 410210, India
| | - Aishwarya Iyer
- Translational Research Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Kharghar, Navi-Mumbai, 410210, India
| | - Naveen K Nair
- Translational Research Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Kharghar, Navi-Mumbai, 410210, India
| | - Indraneel Mittra
- Translational Research Laboratory, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Kharghar, Navi-Mumbai, 410210, India
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Lai CS, Mas RHMH, Nair NK, Mansor SM, Navaratnam V. Chemical constituents and in vitro anticancer activity of Typhonium flagelliforme (Araceae). J Ethnopharmacol 2010; 127:486-494. [PMID: 19833183 DOI: 10.1016/j.jep.2009.10.009] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2009] [Revised: 09/24/2009] [Accepted: 10/06/2009] [Indexed: 05/28/2023]
Abstract
AIM OF THE STUDY Typhonium flagelliforme is an indigenous plant of Malaysia and is used by the local communities to treat cancer. This study aims to identify the chemical constituents of Typhonium flagelliforme particularly those which have antiproliferative properties towards human cancer cell lines. MATERIALS AND METHODS Purification of the chemical constituents by various chromatographic procedures was guided by the antiproliferative activity. Identification of the chemical constituents was carried out by various spectroscopic techniques including high resolution MS and NMR. The antiproliferative activity was assayed using MTT on NCI-H23 (lung cancer) and HS578T (breast cancer) cell lines. Microscopic observation and DeadEnd colourimetric TUNEL assay was used to identify the apoptotic mode of cell death. RESULTS AND CONCLUSION Four pheophorbide related compounds, namely pheophorbide-a, pheophorbide-a', pyropheophorbide-a and methyl pyropheophorbide-a were identified in the most active fraction, D/F19. These constituents exhibited antiproliferative activity against cancer cells and the activity increased following photoactivation. However, the greater antiproliferative activity exhibited by D/F19 itself compared to the pheophorbides and its other subfractions suggests some form of synergistic action between the constituents. The inhibitory effect of D/F19 and the pheophorbides was apoptotic in the absence of light. Other chemical constituents that have been identified in this study include hexadecanoic acid, oleic acid, linoleic acid, linolenic acid, campesterol, stigmasterol and beta-sitosterol. Most of the chemical constituents identified in this plant have not been reported previously.
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Affiliation(s)
- Choon-Sheen Lai
- Centre for Drug Research, Universiti Sains Malaysia, 11800 Penang, Malaysia
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9
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Lai CS, Mas RHMH, Nair NK, Majid MIA, Mansor SM, Navaratnam V. Typhonium flagelliforme inhibits cancer cell growth in vitro and induces apoptosis: an evaluation by the bioactivity guided approach. J Ethnopharmacol 2008; 118:14-20. [PMID: 18436400 DOI: 10.1016/j.jep.2008.02.034] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2007] [Revised: 02/22/2008] [Accepted: 02/29/2008] [Indexed: 05/26/2023]
Abstract
AIM OF THE STUDY Typhonium flagelliforme (Lodd.) Blume (Araceae) is a Malaysian plant used locally to combat cancer. In order to evaluate its antiproliferative activity in vitro and to possibly identify the active chemical constituents, a bioactivity guided study was conducted on the extracts of this plant. MATERIALS AND METHODS The active extracts of Typhonium flagelliforme were fractionated by flash column chromatography and each fraction was evaluated for antiproliferative activity using MTT assay. The apoptotic effect of the active fraction was determined microscopically and by using TUNEL colorimetric assay. GC-MS and NMR were used to determine the chemical constituents of this active fraction. RESULTS Several fractions of the hexane and dichloromethane extracts were found to inhibit the growth of NCI-H23 non-small cell lung carcinoma cell line significantly, with IC(50)<15 microg/ml. However, most of these active fractions were also found to inhibit the growth of non-tumorigenic BALB/c 3T3 mouse fibroblast cell line except for fraction 21 of the dichloromethane extract (D/F21). This particular fraction was not only less cytotoxic to the non-tumorigenic cells, where the IC(50) was 48.6 microg/ml compared to IC(50) 7.5 microg/ml for NCI-H23, but it was also found to induce apoptosis in the cancer cell line. GC-MS analysis revealed that D/F21 contains hexadecanoic acid, 1-hexadecene, phytol and a derivative of phytol. The presence of non-saturated fatty acids in this fraction was confirmed by nuclear magnetic resonance spectroscopy. CONCLUSIONS D/F21 was found to be the active and cancer cell line specific fraction of Typhonium flagelliforme. Its major chemical constituents had been determined spectroscopically.
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Affiliation(s)
- Choon-Sheen Lai
- Centre for Drug Research, Universiti Sains Malaysia, Penang, Malaysia
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10
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Lai CS, Nair NK, Mansor SM, Olliaro PL, Navaratnam V. An analytical method with a single extraction procedure and two separate high performance liquid chromatographic systems for the determination of artesunate, dihydroartemisinin and mefloquine in human plasma for application in clinical pharmacological studies of the drug combination. J Chromatogr B Analyt Technol Biomed Life Sci 2007; 857:308-14. [PMID: 17719858 DOI: 10.1016/j.jchromb.2007.07.037] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2007] [Revised: 07/03/2007] [Accepted: 07/24/2007] [Indexed: 11/16/2022]
Abstract
The combination of two sensitive, selective and reproducible reversed phase liquid chromatographic (RP-HPLC) methods was developed for the determination of artesunate (AS), its active metabolite dihydroartemisinin (DHA) and mefloquine (MQ) in human plasma. Solid phase extraction (SPE) of the plasma samples was carried out on Supelclean LC-18 extraction cartridges. Chromatographic separation of AS, DHA and the internal standard, artemisinin (QHS) was obtained on a Hypersil C4 column with mobile phase consisting of acetonitrile-0.05 M acetic acid adjusted to pH 5.2 with 1.0M NaOH (42:58, v/v) at the flow rate of 1.50 ml/min. The analytes were detected using an electrochemical detector operating in the reductive mode. Chromatography of MQ and the internal standard, chlorpromazine hydrochloride (CPM) was carried out on an Inertsil C8-3 column using methanol-acetonitrile-0.05 M potassium dihydrogen phosphate adjusted to pH 3.9 with 0.5% orthophosphoric acid (50:8:42, v/v/v) at a flow rate of 1.00 ml/min with ultraviolet detection at 284 nm. The mean recoveries of AS and DHA over a concentration range of 30-750 ng/0.5 ml plasma and MQ over a concentration of 75-1500 ng/0.5 ml plasma were above 80% and the accuracy ranged from 91.1 to 103.5%. The within-day coefficients of variation were 1.0-1.4% for AS, 0.4-3.4% for DHA and 0.7-1.5% for MQ. The day-to-day coefficients of variation were 1.3-7.6%, 1.8-7.8% and 2.0-3.4%, respectively. Both the lower limit of quantifications for AS and DHA were at 10 ng/0.5 ml and the lower limit of quantification for MQ was at 25 ng/0.5 ml. The limit of detections were 4 ng/0.5 ml for AS and DHA and 15 ng/0.5 ml for MQ. The method was found to be suitable for use in clinical pharmacological studies.
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Affiliation(s)
- Choon-Sheen Lai
- Centre for Drug Research, Universiti Sains Malaysia, 11800 Penang, Malaysia
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11
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Venkatesh G, Ramanathan S, Mansor SM, Nair NK, Sattar MA, Croft SL, Navaratnam V. Development and validation of RP-HPLC-UV method for simultaneous determination of buparvaquone, atenolol, propranolol, quinidine and verapamil: A tool for the standardization of rat in situ intestinal permeability studies. J Pharm Biomed Anal 2007; 43:1546-51. [PMID: 17157469 DOI: 10.1016/j.jpba.2006.11.013] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2006] [Revised: 11/02/2006] [Accepted: 11/09/2006] [Indexed: 10/23/2022]
Abstract
A simple, sensitive and specific reversed phase high performance liquid chromatographic (RP-HPLC) method with UV detection at 251 nm was developed for simultaneous quantitation of buparvaquone (BPQ), atenolol, propranolol, quinidine and verapamil. The method was applicable in rat in situ intestinal permeability study to assess intestinal permeability of BPQ, a promising lead compound for Leishmania donovani infections. The method was validated on a C-4 column with mobile phase comprising ammonium acetate buffer (0.02 M, pH 3.5) and acetonitrile in the ratio of 30:70 (v/v) at a flow rate of 1.0 ml/min. The retention times for atenolol, quinidine, propranolol, verapamil and BPQ were 4.30, 5.96, 6.55, 7.98 and 8.54 min, respectively. The calibration curves were linear (correlation coefficient > or =0.996) in the selected range of each analyte. The method is specific and sensitive with limit of quantitation of 15 microg/ml for atenolol, 0.8 microg/ml for quinidine, 5 microg/ml for propranolol, 10 microg/ml for verapamil and 200 ng/ml for BPQ. The validated method was found to be accurate and precise in the working calibration range. Stability studies were carried out at different storage conditions and all the analytes were found to be stable. This method is simple, reliable and can be routinely used for accurate permeability characterization.
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Affiliation(s)
- Gantala Venkatesh
- Centre for Drug Research, Universiti Sains Malaysia, 11800 Penang, Malaysia.
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12
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Venkatesh G, Ramanathan S, Nair NK, Mansor SM, Sattar MA, Khan MAH, Navaratnam V. Permeability of atenolol and propranolol in the presence of dimethyl sulfoxide in rat single-pass intestinal perfusion assay with liquid chromatography/UV detection. Biomed Chromatogr 2007; 21:484-90. [PMID: 17294505 DOI: 10.1002/bmc.781] [Citation(s) in RCA: 11] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
A simple and sensitive RP-HPLC-UV method was developed and validated for simultaneous determination of atenolol and propranolol and subsequently applied to investigate the effect of dimethyl sulfoxide in rat in situ intestinal permeability studies. Atenolol (400 microm) and propranolol (100 microm) were perfused in the small intestine of anaesthetized (pentobarbitone sodium 60 mg/kg, i.p.) male Sprague-Dawley rats either in the presence (1, 3 and 5%) or in the absence of dimethyl sulfoxide. There was no significant alteration (p > 0.05) in the permeability of atenolol and propranolol, which indicated there was no effect of various concentrations of dimethyl sulfoxide (1-5%) on the membrane integrity of the rat intestinal tissues. The analytical method was validated on a C(4) column with a mobile phase comprising ammonium acetate buffer (pH 3.5, 0.02 m) and acetonitrile in the ratio of 30:70 (v/v) at a flow rate of 1.0 mL/min. The validated method was found to be accurate and precise and stability studies were carried out at different storage conditions and both analytes were found to be stable. These findings are applicable for determining the absorbability of water-insoluble drugs and new chemical entities for the purpose of classifying them in the biopharmaceutical classification system.
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Affiliation(s)
- Gantala Venkatesh
- Centre for Drug Research, Universiti Sains Malaysia, 11800 Penang, Malaysia.
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13
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Fol M, Chauhan A, Nair NK, Maloney E, Moomey M, Jagannath C, Madiraju MVVS, Rajagopalan M. Modulation of Mycobacterium tuberculosis proliferation by MtrA, an essential two-component response regulator. Mol Microbiol 2006; 60:643-57. [PMID: 16629667 DOI: 10.1111/j.1365-2958.2006.05137.x] [Citation(s) in RCA: 127] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Paired two-component regulatory systems consisting of a sensor kinase and a response regulator are the major means by which bacteria sense and respond to different stimuli. The role of essential response regulator, MtrA, in Mycobacterium tuberculosis proliferation is unknown. We showed that elevating the intracellular levels of MtrA prevented M. tuberculosis from multiplying in macrophages, mice lungs and spleens, but did not affect its growth in broth. Intracellular trafficking analysis revealed that a vast majority of MtrA overproducing merodiploids were associated with lysosomal associated membrane protein (LAMP-1) positive vacuoles, indicating that intracellular growth attenuation is, in part, due to an impaired ability to block phagosome-lysosome fusion. A merodiploid strain producing elevated levels of phosphorylation-defective MtrA (MtrA(D53N)) was partially replicative in macrophages, but was attenuated in mice. Quantitative real-time PCR analyses revealed that expression of dnaA, an essential replication gene, was sharply upregulated during intramacrophage growth in the MtrA overproducer in a phosphorylation-dependent manner. Chromatin immunoprecipitation using anti-MtrA antibodies provided direct evidence that MtrA regulator binds to dnaA promoter in vivo indicating that dnaA promoter is a MtrA target. Simultaneous overexpression of mtrA regulator and its cognate mtrB kinase neither inhibited growth nor sharply increased the expression levels of dnaA in macrophages. We propose that proliferation of M. tuberculosis in vivo depends, in part, on the optimal ratio of phosphorylated to non-phosphorylated MtrA response regulator.
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Affiliation(s)
- Marek Fol
- Biomedical Research, The University of Texas Health Center at Tyler, 11937 U.S. Hwy @271, Tyler, TX 75708-3154, USA
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Ramanathan S, Karupiah S, Nair NK, Olliaro PL, Navaratnam V, Wernsdorfer WH, Mansor SM. A new and simple solid-phase extraction method for LC determination of pyronaridine in human plasma. J Chromatogr B Analyt Technol Biomed Life Sci 2005; 824:45-50. [PMID: 16046285 DOI: 10.1016/j.jchromb.2005.06.034] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2004] [Revised: 06/14/2005] [Accepted: 06/24/2005] [Indexed: 11/19/2022]
Abstract
A new approach using a simple solid-phase extraction technique has been developed for the determination of pyronaridine (PND), an antimalarial drug, in human plasma. After extraction with C18 solid-phase sorbent, PND was analyzed using a reverse phase chromatographic method with fluorescence detection (at lambda(ex)=267 nm and lambda(em)=443 nm). The mean extraction recovery for PND was 95.2%. The coefficient of variation for intra-assay precision, inter-assay precision and accuracy was less than 10%. The quantification limit with fluorescence detection was 0.010 microg/mL plasma. The method described herein has several advantages over other published methods since it is easy to perform and rapid. It also permits reducing both, solvent use and sample preparation time. The method has been used successfully to assay plasma samples from clinical pharmacokinetic studies.
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Affiliation(s)
- S Ramanathan
- Centre for Drug Research, Universiti Sains Malaysia, 11800 Penang, Malaysia
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15
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Selvamuniandy TS, Mohamed N, Mansor SM, Nair NK, Navaratnam V. Determination of 6,4'-bis-(2-imidazolinylhydrazone)-2-phenylimidazo[1,2-a]py ridine in plasma and whole blood by high-performance liquid chromatography. J Chromatogr B Biomed Sci Appl 1997; 700:209-13. [PMID: 9390731 DOI: 10.1016/s0378-4347(97)00246-6] [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] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
A selective and sensitive HPLC assay for the quantitative determination of a new antifilarial drug, 6,4'-bis-(2-imidazolinylhydrazone)-2-phenylimidazo[1,2-a]pyr idine (CDR 101) is described. After extraction from plasma and blood, CDR 101 was analysed using a C18 Nucleosil ODS column (250x4.6 mm, 5 microm particle size) and mobile phase of acetonitrile-0.05 M ammonium acetate adjusted to pH 3.0, with UV detection at 318 nm. The mean recoveries of CDR 101 in plasma and blood over a concentration range of 25-500 ng/ml were 95.5+/-2.01% and 83.3+/-1.87%, respectively. The within-day and day-to-day coefficient of variations for plasma were 3.23-6.21% and 2.59-9.90%, respectively, those for blood were 2.59-5.92% and 2.89-6.82%, respectively. The minimum detectable concentration for CDR 101 was 1 ng/ml in plasma and 2.5 ng/ml in whole blood. This method was found to be suitable for clinical pharmacokinetic studies.
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16
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Jayaraman SD, Ismail S, Nair NK, Navaratnam V. Determination of pyronaridine in blood plasma by high-performance liquid chromatography for application in clinical pharmacological studies. J Chromatogr B Biomed Sci Appl 1997; 690:253-7. [PMID: 9106050 DOI: 10.1016/s0378-4347(96)00410-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
A method is described for the determination of pyronaridine in plasma using high-performance liquid chromatography with fluorescence detection. The method involves liquid-liquid extraction with phosphate buffer (pH 6.0, 0.05 M) and diethyl ether-hexane (70:30%, v/v) and chromatographic separation on a C18 column (Nucleosil, 250 x 4.6 mm I.D., 5 microns particle size) with acetonitrile-0.05 M phosphate buffer pH 6.0 (60:40%, v/v) as the mobile phase (1 ml/min) and detection by fluorescence (lambda ex = 267 nm, lambda em = 443 nm). The detector response is linear up to 1000 ng and the overall recoveries of pyronaridine and quinine were 90.0 and 60.3%, respectively. The assay procedure was adequately sensitive to measure 10 ng/ml pyronaridine in plasma samples with acceptable precision (< 15% C.V.). The method was found to be suitable for use in clinical pharmacological studies.
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Affiliation(s)
- S D Jayaraman
- Centre for Drug Research, Universiti Sains Malaysia, Penang, Malaysia
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17
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Mansor SM, Navaratnam V, Yahaya N, Nair NK, Wernsdorfer WH, Degen PH. Determination of a new antimalarial drug, benflumetol, in blood plasma by high-performance liquid chromatography. J Chromatogr B Biomed Appl 1996; 682:321-5. [PMID: 8844426 DOI: 10.1016/0378-4347(96)00086-2] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
A rapid and selective high-performance liquid chromatographic assay for determination of a new antimalarial drug (benflumetol, BFL) is described. After extraction with hexane-diethyl ether (70:30, v/v) from plasma, BFL was analysed using a C18 Partisil 10 ODS-3 reversed-phase stainless steel column and a mobile phase of acetonitrile-0.1 M ammonium acetate (90:10, v/v) adjusted to pH 4.9 with ultraviolet detection at 335 nm. The mean recovery of BFL over a concentration range of 50-400 ng/ml was 96.8 +/- 5.2%. The within-day and day-to-day coefficients of variation were 1.8-4.0 and 1.8-4.2%, respectively. The minimum detectable concentration in plasma for BFL was 5 ng/ml with a C.V. of less than 10%. This method was found to be suitable for clinical pharmacokinetic studies.
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Affiliation(s)
- S M Mansor
- Universiti Sains Malaysia, Minden, Penang, Malaysia
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Navaratnam V, Mansor SM, Chin LK, Mordi MN, Asokan M, Nair NK. Determination of artemether and dihydroartemisinin in blood plasma by high-performance liquid chromatography for application in clinical pharmacological studies. J Chromatogr B Biomed Appl 1995; 669:289-94. [PMID: 7581905 DOI: 10.1016/0378-4347(94)00109-i] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
A selective reproducible high-performance liquid chromatographic assay for the simultaneous quantitative determination of the antimalarial compound artemether (ARM), dihydroartemisinin (DQHS) and artemisinin (QHS), as internal standard, is described. After extraction from plasma, ARM and DQHS were analysed using a Lichrocart/Lichrosphere 100 CN stainless-steel column and a mobile phase of acetonitrile-0.05 M acetic acid (15:85, v/v) adjusted to pH 5.0, and electrochemical detection in the reductive mode. The mean recovery of ARM and DQHS over a concentration range of 30-120 ng/ml was 81.6% and 93.4%, respectively. The within-day coefficients of variation were 0.89-7.01% for ARM and 3.45-8.11% for DQHS. The day-to-day coefficients of variation were 2.06-8.43% and 3.22-6.33%, respectively. The minimum detectable concentration for ARM and DQHS in plasma was 2.5 and 1.25 ng/ml for both compounds. The method was found to be suitable for use in clinical pharmacological studies.
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Affiliation(s)
- V Navaratnam
- Centre for Drug Research, Universiti Sains Malaysia, Penang
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Ramanathan S, Nair NK, Mansor SM, Navaratnam V. Determination of the antifilarial drug UMF-078 and its metabolites UMF-060 and flubendazole in whole blood using high-performance liquid chromatography. J Chromatogr B Biomed Appl 1994; 655:269-73. [PMID: 8081473 DOI: 10.1016/s0378-4347(94)80028-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
A rapid and selective high-performance liquid chromatographic (HPLC) method for the simultaneous determination of the antifilarial drug UMF-078 (I) and its metabolites UMF-060 (II) and flubendazole (III) is described. After a simple extraction from whole blood, the compounds were determined by HPLC using a C18 Inertsil ODS-2 reversed-phase column with methanol-0.05M ammonium acetate (pH 4.0) as the mobile phase and ultraviolet detection at 291 nm. The average recoveries of I, II and III over the concentration range 20-500 ng ml-1 were 69.9 +/- 4.7, 85.6 +/- 4.4 and 85.1 +/- 6.0%, respectively. The minimum detectable concentrations in whole blood for I, II and III were 10, 7 and 7 ng ml-1, respectively. This method was found to be suitable for pharmacokinetic studies.
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Affiliation(s)
- S Ramanathan
- Centre for Drug Research, Universiti Sains Malaysia, Penang
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Ramanathan S, Nair NK, Mansor SM, Navaratnam V. Determination of a new antifilarial drug, UMF-058, and mebendazole in whole blood by high-performance liquid chromatography. J Chromatogr 1993; 615:303-7. [PMID: 8335708 DOI: 10.1016/0378-4347(93)80345-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
A rapid and selective high-performance liquid chromatographic assay for simultaneous quantitative determination of a new antifilarial drug (UMF-058, I) and mebendazole (MBZ) is described. After a simple extraction from whole blood, both compounds were analysed using a C18 Nova Pak reversed-phase column and a mobile phase of methanol-0.05 M ammonium dihydrogenphosphate (50:50, v/v) adjusted to pH 4.0, with ultraviolet detection at 291 nm. The average recoveries of I and MBZ over a concentration range of 25-250 ng/ml were 92.0 +/- 7.7 and 84.4 +/- 4.4%, respectively. The minimum detectable concentrations in whole blood for I and MBZ were 7 and 6 ng/ml, respectively. This method was found to be suitable for pharmacokinetic studies.
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Affiliation(s)
- S Ramanathan
- Centre for Drug Research, Universiti Sains Malaysia Malaysia, Penang
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Nair NK, Navaratnam V, Rajananda V. Analysis of illicit heroin. I. An effective thin-layer chromatographic system for separating eight opiates and five adulterants. J Chromatogr A 1986; 366:363-72. [PMID: 3782326 DOI: 10.1016/s0021-9673(01)93484-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
A thin-layer chromatographic (TLC) system with chloroform-n-hexane-triethylamine (9:9:4) as eluent that is capable of separating eight opiates and five potential adulterants, has been developed for the analysis of illicit heroin. The system was tested using illicit heroin samples and the results were confirmed by gas chromatography. The limit of detection is 0.1 microgram. Thirty-five TLC systems reported in the literature for opiate analysis were classified according to their resolving power.
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Rajananda V, Nair NK, Navaratnam V. An evaluation of TLC systems for opiate analysis. Bull Narc 1985; 37:35-47. [PMID: 4063572] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The authors selected 38 thin-layer-chromatography (TLC) systems described in the available literature published over the last 10 years and evaluated those systems with respect to their suitability for detection and identification of opiates in urine, opium and heroin, as well as adulterants in heroin. A total of 14 substances: 8 opiates (morphine, 6-monoacetylmorphine, diacetylmorphine, codeine, acetylcodeine, noscapine, papaverine and thebaine) and 6 adulterants (ephedrine, quinine, methadone, caffeine, cocaine and strychnine) were used as test samples for this research. Using laboratory-coated plates and pre-coated plates, 15 and 13 TLC systems, respectively, were found to be able to detect and identify morphine and codeine in urine without interference from the remaining 12 substances. For the detection of opiates in opium samples as well as opiates and adulterants in illicit heroin samples the TLC system: chloroform-n-hexane-triethylamine (9:9:4) which was developed by the National Drug Research Centre, Penang, Malaysia, was found to be most suitable on both laboratory-coated and pre-coated plates. In addition, the following two systems, one on laboratory-coated plates--hexane-chloroform-diethylamine (50:30:7)--and the other on pre-coated plates--benzene-dioxane-ethanol-ammonia (50:40:5:5; T-7)--were also found to be among most suitable TLC systems for the analysis of opiates in opium samples. The article also presents the relative cost of each of the 38 evaluated TLC systems.
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Nair NK, Smith L. Reasons for not using contraceptives: an international comparison. Stud Fam Plann 1984; 15:84-92. [PMID: 6538706] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
This study presents the main reasons for currently not using contraceptives given by currently in-union, nonpregnant women 15-44 years of age in three Asian countries (Bangladesh, Korea, and Thailand) and three Latin American countries (Barbados, Colombia, and Costa Rica). Desire for next child, side effects or health reasons, and temporary infecundity were the most commonly given reasons for current nonuse. In Korea, Thailand, and Barbados, there is little or no disapproval of contraceptives, but in the other countries there is an appreciable amount. Variations in the reasons given by selected socioeconomic and demographic characteristics of the respondents are examined. Among these characteristics, age of the women, number of living children, and ever use of family planning methods are generally the most powerful discriminators of the main reason for nonuse.
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Abstract
Whether or not increased prevalence of oral contraceptive use in developing countries is associated with increased morbidity and mortality from circulatory system diseases is a serious concern for health and family planning administrators. An analysis of Taiwan's mortality statistics to determine whether such an association existed was undertaken, taking advantage of the excellent vital statistics and medical care systems existing there. The analysis failed to demonstrate that death rates from circulatory system diseases among Taiwanese women of childbearing age have increased since the promotion of oral contraceptive use began in 1967. In fact, mortality from all forms of circulatory system diseases has generally declined since 1967 and the slopes of declines for females of childbearing age who were exposed to oral contraceptives were somewhat greater than those of males of the corresponding age groups.
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26
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Nair NK, Chow LP. Fertility intentions and behavior: some findings from Taiwan. Stud Fam Plann 1980; 11:255-63. [PMID: 7404609] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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27
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Abstract
Site of feedback control of FSH secretion in the male rat was studied by measuring changes in serum LH, FSH and hypothalamic LH-RH by radioimmunoassay in rats after castration and after 500 rad X-irradiation to the testis. The rise in serum LH and FSH in castrated animals was associated with a significant fall in hypothalamic LH-RH 16 and 24 days after castration. Serum FSH rose significantly after X-irradiation without a significant change in serum LH or hypothalamic LH-RH content up to 30 days after irradiation. When pituitary halves from X-irradiated animals were incubated in vitro in the presence or absence of synthetic LH-RH, there was a significant rise in FSH (but not LH) released in the incubation medium in the absence of added LH-RH. The response of the pituitaries to LH-RH was, however, not different between control and irradiated rats. It is concluded that the testicular FSH-inhibitory substance acts predominantly at the pituitary gland on the LH-RH independent release of FSH.
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