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Saini NK, Suresh PS, Lella M, Bhamidipati RK, Rajagopal S, Mullangi R. LC-MS/MS determination of tideglusib, a novel GSK-3β inhibitor in mice plasma and its application to a pharmacokinetic study in mice. J Pharm Biomed Anal 2017; 148:100-107. [PMID: 28982059 DOI: 10.1016/j.jpba.2017.09.022] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2017] [Revised: 09/14/2017] [Accepted: 09/15/2017] [Indexed: 11/17/2022]
Abstract
A sensitive, specific and rapid LC-ESI-MS/MS method has been developed and validated for the quantification of tideglusib in mice plasma using warfarin as an internal standard (I.S.) as per regulatory guidelines. Sample preparation was accomplished through liquid-liquid extraction process. Chromatographic separation was performed on Atlantis dC18 column using mobile phase A (acetonitrile) and B (5mM ammonium acetate in water) in a flow-gradient mode. Elution of tideglusib and the I.S. occurred at ∼2.06 and 1.29min, respectively. The total chromatographic run time was 3.2min. A linear response function was established in the concentration range of 20.2-1008ng/mL. The intra- and inter-day accuracy and precision were in the range of 4.61-12.6 and 6.04-11.8%, respectively. This novel method has been applied to a pharmacokinetic study in mice.
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Affiliation(s)
- Neeraj Kumar Saini
- Drug Metabolism and Pharmacokinetics, Jubilant Biosys Ltd., Industrial Suburb, Yeshwanthpur, Bangalore 560 022, India
| | - P S Suresh
- Drug Metabolism and Pharmacokinetics, Jubilant Biosys Ltd., Industrial Suburb, Yeshwanthpur, Bangalore 560 022, India
| | - Mahalakhsmi Lella
- Drug Metabolism and Pharmacokinetics, Jubilant Biosys Ltd., Industrial Suburb, Yeshwanthpur, Bangalore 560 022, India
| | - Ravi Kanth Bhamidipati
- Drug Metabolism and Pharmacokinetics, Jubilant Biosys Ltd., Industrial Suburb, Yeshwanthpur, Bangalore 560 022, India
| | - Sriram Rajagopal
- Drug Metabolism and Pharmacokinetics, Jubilant Biosys Ltd., Industrial Suburb, Yeshwanthpur, Bangalore 560 022, India
| | - Ramesh Mullangi
- Drug Metabolism and Pharmacokinetics, Jubilant Biosys Ltd., Industrial Suburb, Yeshwanthpur, Bangalore 560 022, India.
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Todmal U, Suresh PS, Zainuddin M, Kanth Bhamidipati R, Samanta SK, Hallur G, Rajagopal S, Rajagopal S, Mullangi R. Validated LC-MS-MS Method for Determination of SF0034 in Mice Plasma: Application to a Pharmacokinetic Study in Mice. J Chromatogr Sci 2017; 55:750-756. [PMID: 28383683 DOI: 10.1093/chromsci/bmx032] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Indexed: 11/14/2022]
Abstract
A rapid and sensitive assay method has been developed and validated using liquid chromatography coupled to tandem mass spectrometry with electrospray ionization in the positive-ion mode for the estimation of SF0034 in mice plasma. The assay procedure involves a simple protein precipitation of SF0034 and tolbutamide (internal standard, IS) from mice plasma. Chromatographic separation was performed on an Atlantis dC18 column using an isocratic mobile phase comprising 0.2% formic acid:acetonitrile (10:90, v/v) at a flow rate of 0.60 mL/min. The total run time was 2.5 min. For mass spectrometric detection, the multiple reaction monitoring was used and ion transitions monitored were m/z 322 → 248 for SF0034 and 271 → 155 for IS. Method validation was performed as per regulatory guidelines and the results met the acceptance criteria. A calibration curve was constructed in the range of 2.08-2,078 ng/mL. The intra- and inter-day precision was in the range of 1.06-14.4% and 7.16-11.7%, respectively. This novel method has been applied to a pharmacokinetic study in mice.
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Affiliation(s)
- Umesh Todmal
- Drug Metabolism and Pharmacokinetics, Jubilant Biosys Ltd, Industrial Suburb, Yeshwanthpur, Bangalore 560022, India
| | - P S Suresh
- Drug Metabolism and Pharmacokinetics, Jubilant Biosys Ltd, Industrial Suburb, Yeshwanthpur, Bangalore 560022, India
| | - Mohd Zainuddin
- Drug Metabolism and Pharmacokinetics, Jubilant Biosys Ltd, Industrial Suburb, Yeshwanthpur, Bangalore 560022, India
| | - Ravi Kanth Bhamidipati
- Drug Metabolism and Pharmacokinetics, Jubilant Biosys Ltd, Industrial Suburb, Yeshwanthpur, Bangalore 560022, India
| | - Swapan Kumar Samanta
- Department of Medicinal Chemistry, Jubilant Biosys Ltd, Industrial Suburb, Yeshwanthpur, Bangalore 560022, India
| | - Gurulingappa Hallur
- Department of Medicinal Chemistry, Jubilant Biosys Ltd, Industrial Suburb, Yeshwanthpur, Bangalore 560022, India
| | - Sridharan Rajagopal
- Department of Medicinal Chemistry, Jubilant Biosys Ltd, Industrial Suburb, Yeshwanthpur, Bangalore 560022, India
| | - Sriram Rajagopal
- Drug Metabolism and Pharmacokinetics, Jubilant Biosys Ltd, Industrial Suburb, Yeshwanthpur, Bangalore 560022, India
| | - Ramesh Mullangi
- Drug Metabolism and Pharmacokinetics, Jubilant Biosys Ltd, Industrial Suburb, Yeshwanthpur, Bangalore 560022, India
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Giri KK, Suresh PS, Saim SM, Zainuddin M, Bhamidipati RK, Dewang P, Hallur MS, Rajagopal S, Rajagopal S, Mullangi R. Validation of an LC-MS/MS method for simultaneous detection of four HDAC inhibitors - belinostat, panobinostat, rocilinostat and vorinostat in mouse plasma and its application to a mouse pharmacokinetic study. Biomed Chromatogr 2016; 31. [PMID: 27925271 DOI: 10.1002/bmc.3912] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2016] [Revised: 11/16/2016] [Accepted: 11/28/2016] [Indexed: 01/15/2023]
Abstract
A sensitive and rapid LC-MS/MS method was developed and validated for the simultaneous quantitation of four HDAC inhibitors, namely belinostat (BST), panobinostat (PST), rocilinostat (RST) and vorinostat (VST), in mouse plasma as per regulatory guidelines. The analytes and internal standard were extracted from 50 μL mouse plasma by protein precipitation, followed by chromatographic separation using an Atlantis C18 column with an isocratic mobile phase comprising 0.1% formic acid-acetonitrile (25:75, v/v) at a flow rate of 0.5 mL/min within 2.5 min. Detection and quantitation were done by multiple reaction monitoring on a triple quadrupole mass spectrometer following the transitions: m/z 319 → 93, 350 → 158, 434 → 274 and 265 → 232 for BST, PST, RST and VST, respectively, in the positive ionization mode. The calibration curves were linear from 2.92 to 2921 ng/mL for BST and PST and from 1.01 to 1008 ng/mL for RST and VST with r2 ≥ 0.99 for all of the analytes. The intra- and inter-batch accuracy and precision (CV) across quality controls varied from 85.5 to 112% and from 2.30 to 12.5, respectively, for all of the analytes. Analytes were found to be stable under different stability conditions. The method was applied to an i.v. pharmacokinetic study in mice.
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Affiliation(s)
- Kalpesh Kumar Giri
- Drug Metabolism and Pharmacokinetics, Jubilant Biosys Ltd, Industrial Suburb, Bangalore, India
| | - P S Suresh
- Drug Metabolism and Pharmacokinetics, Jubilant Biosys Ltd, Industrial Suburb, Bangalore, India
| | - Syed Mohd Saim
- Drug Metabolism and Pharmacokinetics, Jubilant Biosys Ltd, Industrial Suburb, Bangalore, India
| | - Mohd Zainuddin
- Drug Metabolism and Pharmacokinetics, Jubilant Biosys Ltd, Industrial Suburb, Bangalore, India
| | - Ravi Kanth Bhamidipati
- Drug Metabolism and Pharmacokinetics, Jubilant Biosys Ltd, Industrial Suburb, Bangalore, India
| | - Purushottam Dewang
- Department of Medicinal Chemistry, Jubilant Biosys Ltd, Industrial Suburb, Bangalore, India
| | - Mahanandeesha S Hallur
- Department of Medicinal Chemistry, Jubilant Biosys Ltd, Industrial Suburb, Bangalore, India
| | - Sridharan Rajagopal
- Department of Medicinal Chemistry, Jubilant Biosys Ltd, Industrial Suburb, Bangalore, India
| | - Sriram Rajagopal
- Drug Metabolism and Pharmacokinetics, Jubilant Biosys Ltd, Industrial Suburb, Bangalore, India
| | - Ramesh Mullangi
- Drug Metabolism and Pharmacokinetics, Jubilant Biosys Ltd, Industrial Suburb, Bangalore, India
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Suresh PS, Devaraj VC, Srinivas NR, Mullangi R. Review of bioanalytical assays for the quantitation of various HDAC inhibitors such as vorinostat, belinostat, panobinostat, romidepsin and chidamine. Biomed Chromatogr 2016; 31. [PMID: 27511598 DOI: 10.1002/bmc.3807] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [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: 07/15/2016] [Accepted: 08/05/2016] [Indexed: 01/21/2023]
Abstract
Histone deacetylase inhibitors (HDAC inhibitors) are used to treat malignancies such as cutaneous T cell lymphoma and peripheral T cell lymphoma. Only four drugs are approved by the US Food and Drug Administration, namely vorinostat, romidepsin, panobinostat and belinostat, while chidamide has been approved in China. There are a number of bioanalytical methods reported for the measurement of HDAC inhibitors in clinical (human plasma and serum) and preclinical (mouse plasma, rat plasma, urine and tissue homogenates, etc.) studies. This review covers various HDAC inhibitors such as vorinostat, romidepsin, panobinostat, belinostat and chidamide. In addition to providing a comprehensive review of the available methods for the above mentioned HDAC inhibitors, it also provides case studies with perspectives for chosen drugs. Based on the review, it is concluded that the published methodologies using either HPLC or LC-MS/MS are well suited for the quantification of HDAC inhibitors in various biological fluids to delineate pharmacokinetic data.
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Affiliation(s)
- P S Suresh
- Jubilant Biosys, 2nd Stage, Bangalore, India
| | - V C Devaraj
- Jubilant Biosys, 2nd Stage, Bangalore, India
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Srinivas NR, Richter W, Devaraj VC, Suresh PS, Bhamdipati RK, Mullangi R. Infusion Rate Dependent Pharmacokinetics of Bendamustine with Altered Formation of γ-hydroxybendamustine (M3) Metabolite Following 30- and 60-min Infusion of Bendamustine in Rats. Drug Res (Stuttg) 2016; 66:351-6. [PMID: 27120083 DOI: 10.1055/s-0042-105745] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Bendamustine is an alkylating agent administered as 1 h intravenous infusion in the clinic for the treatment of malignant haematological cancers. The aim of the study was to evaluate the pharmacokinetics of bendamustine and its key cytochrome P 450 (CYP) 1A2 mediated γ-hydroxybendamustine (M3) metabolite after 30- and 60-min intravenous infusion of bendamustine in rats. 2 groups were assigned to receive bendamustine either as 30- or 60-min infusion and doses were normalized to 15 mg/kg for the sake of statistical evaluation. Serial pharmacokinetic samples were collected and were analysed for the circulatory levels of bendamustine and its M3 metabolite. Standard pharmacokinetic parameters were generated for bendamustine and its M3 metabolite. Regardless of the intravenous regimens, Cmax coincided with end of infusion for both bendamustine and its M3 metabolite. Immediately after stoppage of infusion, a rapid decline in the plasma levels occurred for both bendamustine and M3 metabolite. The Cmax and AUC0-∞ parameters for bendamustine after 60-min infusion were 1.90 and 1.34-fold higher; while CL was lower by 1.32-fold as compared to the 30-min infusion. In contrast, the Cmax and AUC0-∞ after 30-min infusion for the M3 metabolite was 2.15- and 2.78-fold greater; while CL was 2.32-fold lower when compared to the 60-min infusion. However, T1/2 and Vz values were similar between the 2 intravenous treatments for bendamustine or the M3 metabolite. The data unequivocally confirmed the existence of differential pharmacokinetics of bendamustine and its M3 metabolite as the function of the duration of intravenous infusion.
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Affiliation(s)
- N R Srinivas
- Suramus Bio, Drug Development, I Phase, J.P. Nagar, Bangalore, India
| | - W Richter
- TUBE Pharmaceuticals GmbH, Leberstr. 20, Wien, Austria
| | - V C Devaraj
- Jubilant Biosys, 2nd Stage, Industrial Suburb, Yeshwanthpur, Bangalore, India
| | - P S Suresh
- Jubilant Biosys, 2nd Stage, Industrial Suburb, Yeshwanthpur, Bangalore, India
| | - R K Bhamdipati
- Jubilant Biosys, 2nd Stage, Industrial Suburb, Yeshwanthpur, Bangalore, India
| | - R Mullangi
- Jubilant Biosys, 2nd Stage, Industrial Suburb, Yeshwanthpur, Bangalore, India
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Suresh PS, Srinivas NR, Mullangi R. A concise review of the bioanalytical methods for the quantitation of sitagliptin, an important dipeptidyl peptidase-4 (DPP4) inhibitor, utilized for the characterization of the drug. Biomed Chromatogr 2016; 30:749-71. [DOI: 10.1002/bmc.3705] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2015] [Revised: 02/03/2016] [Accepted: 02/07/2016] [Indexed: 01/21/2023]
Affiliation(s)
- P. S. Suresh
- Jubilant Biosys; 2nd Stage, Industrial Suburb, Yeswanthpur Bangalore 560 022 India
| | | | - Ramesh Mullangi
- Jubilant Biosys; 2nd Stage, Industrial Suburb, Yeswanthpur Bangalore 560 022 India
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Sharma K, Suresh PS, Mullangi R, Srinivas NR. Quantitation of VEGFR2 (vascular endothelial growth factor receptor) inhibitors - review of assay methodologies and perspectives. Biomed Chromatogr 2014; 29:803-34. [DOI: 10.1002/bmc.3370] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2014] [Revised: 09/23/2014] [Accepted: 09/29/2014] [Indexed: 01/26/2023]
Affiliation(s)
- Kuldeep Sharma
- Jubilant Biosys, Second Stage; Industrial Suburb; Yeswanthpur Bangalore- 560 022 India
| | - P. S. Suresh
- Jubilant Biosys, Second Stage; Industrial Suburb; Yeswanthpur Bangalore- 560 022 India
| | - Ramesh Mullangi
- Jubilant Biosys, Second Stage; Industrial Suburb; Yeswanthpur Bangalore- 560 022 India
| | - N. R. Srinivas
- Semler Research; VI Phase, J. P. Nagar Bangalore- 560 078 India
- CEO, Bioneeds India Private Lmited, Tumkur Road; Nelamangala Taluk, Bangalore Rural District; India
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Suresh PS, Mullangi R, Sukumaran SK. Highly sensitive LC-MS/MS method for determination of galantamine in rat plasma: application to pharmacokinetic studies in rats. Biomed Chromatogr 2014; 28:1633-40. [PMID: 24801995 DOI: 10.1002/bmc.3191] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [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: 12/18/2013] [Revised: 02/19/2014] [Accepted: 02/26/2014] [Indexed: 11/06/2022]
Abstract
A rapid and highly sensitive assay method has been developed and validated for the estimation of galantamine (GLM) in rat plasma using liquid chromatography coupled to tandem mass spectrometry with electrospray ionization in the positive-ion mode. The assay procedure involves a simple liquid-liquid extraction of GLM and phenacetin (internal standard, IS) from rat plasma using acetonitrile. Chromatographic separation was achieved with 0.2% formic acid:acetonitrile (50:50, v/v) at a flow rate of 0.60 mL/min on an Atlantis dC18 column with a total run time 2.5 min. The MS/MS ion transitions monitored were 288.10 → 213.10 for GLM and 180.10 → 110.10 for IS. Method validation was performed as per United States Food and Drug Administration guidelines and the results met the acceptance criteria. The lower limit of quantitation achieved was 0.12 ng/mL and linearity was observed from 0.12 to 525 ng/mL. The intra- and inter-day precision were in the ranges of 4.73-11.7 and 5.83-8.64%, respectively. This novel method has been applied to a pharmacokinetic study in rats.
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Affiliation(s)
- P S Suresh
- Department of Pharmaceutics, School of Pharmaceutical Sciences, Vels Institute of Science Technology and Advanced Studies, Vels University, Chennai, 600117, India
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Suresh PS, Ma S, Migliaccio A, Chen G. Protein-Tyrosine Phosphatase H1 Increases Breast Cancer Sensitivity to Antiestrogens by Dephosphorylating Estrogen Receptor at Tyr537. Mol Cancer Ther 2013; 13:230-8. [DOI: 10.1158/1535-7163.mct-13-0610] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Suresh PS, Dixit A, Giri S, Rajagopal S, Mullangi R. Development and validation of a liquid chromatography-tandem mass spectrometry method for quantitation of indomethacin in rat plasma and its application to a pharmacokinetic study in rats. Biomed Chromatogr 2012; 27:496-501. [PMID: 23059909 DOI: 10.1002/bmc.2818] [Citation(s) in RCA: 3] [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] [Received: 07/30/2012] [Accepted: 08/24/2012] [Indexed: 11/10/2022]
Abstract
A highly sensitive and rapid bioanalytical method has been developed and validated for the estimation of indomethacin in rat plasma with liquid chromatography coupled to tandem mass spectrometry with electrospray ionization in the positive-ion mode. The assay procedure involves a simple liquid-liquid extraction of indomethacin and phenacetin (internal standard, IS) from rat plasma with acetonitrile. Chromatographic separation was achieved with 0.2% formic acid-acetonitrile (25:75, v/v) at a flow rate of 0.60 mL/min on an Atlantis dC18 column with a total run time 3.0 min. The MS/MS ion transitions monitored were 357.7 → 139.1 for indomethacin and 180.20 → 110.10 for IS. Method validation and pharmacokinetic study plasma analysis were performed as per FDA guidelines and the results met the acceptance criteria. The lower limit of quantitation achieved was 0.51 ng/mL and the linearity was observed from 0.51 to 25.5 ng/mL. The intra- and inter-day precisions were in the range of 1.00-10.2 and 5.88-9.80%, respectively. This novel method has been applied to an oral pharmacokinetic study in rats.
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Affiliation(s)
- P S Suresh
- Drug Metabolism and Pharmacokinetics, Jubilant Biosys, 2nd Stage, Industrial Suburb, Yeshwanthpur, Bangalore, India
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Suresh PS, Punde RR, Gupta M, Dixit A, Giri S, Rajagopal S, Mullangi R. A highly sensitive LC-MS/MS method for the determination of S-raclopride in rat plasma: application to a pharmacokinetic study in rats. Biomed Chromatogr 2010; 25:930-7. [PMID: 21154642 DOI: 10.1002/bmc.1547] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2010] [Accepted: 09/10/2010] [Indexed: 11/07/2022]
Abstract
A highly sensitive and rapid assay method has been developed and validated for the estimation of S-(-)-raclopride (S-RCP) in rat plasma with liquid chromatography coupled to tandem mass spectrometry with electrospray ionization in the positive ion mode. The assay procedure involves a simple liquid-liquid extraction technique for extraction of S-RCP and phenacetin (internal standard, IS) from rat plasma. Chromatographic separation was achieved with 0.2% formic acid : acetonitrile (80:20, v/v) at a flow rate of 0.30 mL/min on a Phenomenex Prodigy C(18) column with a total run time of 4.5 min. The MS/MS ion transitions monitored were 347.2 → 112.1 for S-RCP and 180.1 → 110.1 for IS. Method validation and pre-clinical sample analysis were performed as per FDA guidelines and the results met the acceptance criteria. The lower limit of quantitation achieved was 0.05 ng/mL and the linearity range was extended from 0.05 to 152 ng/mL in rat plasma. The intra-day and inter-day precisions were 0.23-10.5 and 3.74-7.29%, respectively. This novel method was applied to a pharmacokinetic study of S-RCP in rats.
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Affiliation(s)
- P S Suresh
- Drug Metabolism and Pharmacokinetics, Jubilant Biosys Ltd, 2nd Stage, Industrial Suburb, Yeshwanthpur, Bangalore-560 022, India
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Suresh PS, Giri S, Husain R, Mullangi R. A highly sensitive LC-MS/MS method for the determination of S-citalopram in rat plasma: application to a pharmacokinetic study in rats. Biomed Chromatogr 2010; 24:1052-8. [DOI: 10.1002/bmc.1405] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Zhao W, Low HY, Suresh PS. Cross-linked and chemically functionalized polymer supports by reactive reversal nanoimprint lithography. Langmuir 2006; 22:5520-4. [PMID: 16732686 DOI: 10.1021/la052523w] [Citation(s) in RCA: 2] [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: 05/09/2023]
Abstract
A new format of polymer support having cross-linked polymeric micro- and nanoarrays has been fabricated via reactive reversal nanoimprint lithography. Reactive reversal nanoimprint lithography is a relatively simple method to imprint highly cross-linked and chemically tunable polymers. An array of chloromethyl-functionalized cross-linked polystyrene has been imprinted on hard (silicon) and soft (polymer) substrates, and a model esterification reaction is demonstrated. The imprints have been found to be relatively stable under both static and dynamic stability tests carried out in various organic solvents. The chemical functionality is evenly distributed over the imprinted array. This method of fabricating polymer supports offers a high degree of freedom in terms of the choice of chemical functionality, the types of polymer matrix, and the size of the polymer support. The functional polymer support has potential applications for chemical and biological assays.
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Affiliation(s)
- Wei Zhao
- Institute of Materials Research and Engineering, 3, Research Link, Singapore 117602
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Mahmood S, Suresh PS, Carley F, Bruce IN, Tullo AB. Surgically induced necrotising scleritis: report of a case presenting 51 years following strabismus surgery. Eye (Lond) 2002; 16:503-4. [PMID: 12101467 DOI: 10.1038/sj.eye.6700033] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
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Abstract
PURPOSE To investigate the safety and efficacy of phacoemulsification with intraocular lens implantation in eyes affected by uveitis. METHODS A retrospective case series is presented including casenote review and update patient examinations. Patient data were withdrawn from the Uveitis Clinic database. All uveitis patients undergoing phacoemulsification with intraocular lens implantation from August 1995 to November 2000 were included. A pre-operative preparation protocol was used. Operative and post-operative complications, degree of postoperative inflammation, best-corrected and final visual acuity were the main outcome measures. RESULTS Eighty-six eyes of 75 patients underwent surgery, which in 11 cases was combined with trabeculectomy. Mean follow-up was 24.1 months. Eight eyes (10%) had severe or fibrinous uveitis post-operatively. The mean delay between surgery and return to baseline treatment was 8.6 weeks. Posterior capsule opacification occurred in 42% of eyes and Nd-YAG capsulotomy was required in 21%. Cystoid macular oedema was seen in 2 eyes. Seventy-two per cent of eyes retain a visual acuity of 6/9 or better, and 87% of eyes retain a post-operative improvement of 2 or more lines of Snellen acuity. CONCLUSIONS With careful patient selection, appropriate pre-operative preparation, diligent surgery and close post-operative supervision, phacoemulsification with intraocular lens implantation is safe and effective in the great majority of eyes with uveitis.
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Affiliation(s)
- P S Suresh
- Department of Ophthalmology, Toronto Western Hospital, Ont
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Prasad TS, Suresh PS, Rodrigues G, Patel M, Moriarty AP. Orbital involvement with angiolymphoid hyperplasia with eosinophilia--a benign condition for the practising ophthalmologist to be aware of. Eye (Lond) 2000; 14 ( Pt 3A):390-2. [PMID: 11027009 DOI: 10.1038/eye.2000.97] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
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Suresh PS, Tullo AB. Herpes simplex keratitis. Indian J Ophthalmol 1999; 47:155-65. [PMID: 10858770] [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: 02/16/2023] Open
Abstract
Chronic infection of the cornea by Herpes simplex virus (HSV) continues to be an important cause of unilateral blindness. Despite considerable progress in the understanding of the virus at cellular and molecular levels, the prospect of prevention still appears to be long way off. The development of non-toxic topical antiviral agents has been an important step forward in management. However, correct diagnosis and treatment, in particular, the avoidance of inappropriate use of topical steroid remains as important as ever. This article reviews the virological and clinical aspects of HSV keratitis including the current concepts of pathogenesis and management.
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Abstract
In 20 varicose vein patients, aged twenty-five to forty-five years, and suffering the disease for more than two years, pulse wave velocity (PWV) of the femoral-dorsalis pedis artery of the lower limbs was measured and compared with that of 20 age-matched normal subjects. Blood pressure and fasting serum total cholesterol level, triglycerides, high density lipoprotein (HDL), low density lipoprotein (LDL), very low density lipoprotein (VLDL) were also estimated for these subjects. PWV showed a significant increase (P < 0.001) in varicose vein patients as compared with control subjects. There was no significant difference either in the blood pressure or lipid profile. It appears that neither hypertension nor atherosclerosis is responsible for the increase in PWV in varicosities. On the basis of the present study, it may be suggested that arteries are also involved in the pathogenesis of varicose veins. The involvement of the arterial tree in the pathogenesis of varicose veins, if given due consideration, may add a new dimension to the understanding of many ill-defined facets of this disease.
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