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Venkatesh M, Parthasarathy P. Al 2O 3/ZrO 2 dual-dielectric Gr/CNT nanoribbon vertical tunnel FET based biosensor for genomic classification and S-protein detection in SARS-CoV-2. Heliyon 2024; 10:e30077. [PMID: 38707330 PMCID: PMC11066398 DOI: 10.1016/j.heliyon.2024.e30077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 04/05/2024] [Accepted: 04/18/2024] [Indexed: 05/07/2024] Open
Abstract
The ongoing genetic mutation of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) possesses the capacity to inadvertently lead to an increase in both the rates of transmission and mortality. In this study, we showcase the use of an Al2O3/ZrO2 Dual-Dielectric Gr/CNT Nanoribbon vertical tunnel field-effect transistor biosensor for the purpose of detecting spike proteins of SARS-CoV-2 in clinical samples. The proteins mentioned above are situated within the protein capsids of the virus. The effectiveness of the suggested detector has been assessed through measurements of the alteration in current drain. The present study utilizes the dielectric coefficient analogue of viral proteins as a substitute for biomolecules that exhibit internal hybridization nanogaps. The high sensitivity of the suggested detector, as evaluated on a scale ranging from 0 to 115, suggests its potential as a high-quality sensing instrument. The purpose of this study is to examine the sensitivity of DNA charge density with the aim of identifying any alterations in the virus that may impact its ability to spread and infect humans. The chromosomal composition of SARS-CoV-2 has been determined. The CMC Research Centre, situated in Vellore, Tamil Nadu, India, conducted an examination of SARS-CoV-2 samples. The scientists possess the capability to do genome sequencing on these specimens, so facilitating the examination of mutation patterns and the dispersion of different clades. A total of 250 different mutations were found out of the 600 sequences that were evaluated. The sequencing data consists of a complete collection of 250 distinct variants, including 150 missense mutations, 80 synonymous mutations, 15 mutations in noncoding regions, and 5 deletions. The comprehension of genetic variety is significantly dependent on these mutations. The proposed detector is connected to a variety of previously documented biosensors based on field-effect transistors (FETs), which are employed for the examination of genetic modifications.
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Affiliation(s)
- M. Venkatesh
- Department of Electronics and Communication Engineering, CMR Institute of Technology, Bengaluru, Karnataka, India, 560037
| | - P. Parthasarathy
- Department of Electronics and Communication Engineering, CMR Institute of Technology, Bengaluru, Karnataka, India, 560037
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2
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Priya GL, Rawat N, Sanagavarapu A, Venkatesh M, Andrew Roobert A. Hybrid Silicon Substrate FinFET-Metal Insulator Metal (MIM) Memristor Based Sense Amplifier Design for the Non-Volatile SRAM Cell. Micromachines (Basel) 2023; 14:232. [PMID: 36837932 PMCID: PMC9959831 DOI: 10.3390/mi14020232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Revised: 12/18/2022] [Accepted: 12/25/2022] [Indexed: 06/18/2023]
Abstract
Maintaining power consumption has become a critical hurdle in the manufacturing process as CMOS technologies continue to be downscaled. The longevity of portable gadgets is reduced as power usage increases. As a result, less-cost, high-density, less-power, and better-performance memory devices are in great demand in the electronics industry for a wide range of applications, including Internet of Things (IoT) and electronic devices like laptops and smartphones. All of the specifications for designing a non-volatile memory will benefit from the use of memristors. In addition to being non-volatile, memristive devices are also characterized by the high switching frequency, low wattage requirement, and compact size. Traditional transistors can be replaced by silicon substrate-based FinFETs, which are substantially more efficient in terms of area and power, to improve the design. As a result, the design of non-volatile SRAM cell in conjunction with silicon substrate-based FinFET and Metal Insulator Metal (MIM) based Memristor is proposed and compared to traditional SRAMs. The power consumption of the proposed hybrid design has outperformed the standard Silicon substrate FinFET design by 91.8% better. It has also been reported that the delay for the suggested design is actually quite a bit shorter, coming in at approximately 1.989 ps. The proposed architecture has been made significantly more practical for use as a low-power and high-speed memory system because of the incorporation of high-K insulation at the interface of metal regions. In addition, Monte Carlo (MC) simulations have been run for the reported 6T-SRAM designs in order to have a better understanding of the device stability.
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Affiliation(s)
- G. Lakshmi Priya
- Centre for Innovation and Product Development, Vellore Institute of Technology, Chennai 600127, India
- School of Electronics Engineering, Vellore Institute of Technology, Chennai 600127, India
| | - Namita Rawat
- School of Electronics Engineering, Vellore Institute of Technology, Chennai 600127, India
| | - Abhishek Sanagavarapu
- School of Electronics Engineering, Vellore Institute of Technology, Chennai 600127, India
| | - M. Venkatesh
- Department of ECE, CMR Institute of Technology, Bengaluru 560037, India
| | - A. Andrew Roobert
- Department of ECE, Francis Xavier Engineering College, Tirunelveli 627003, India
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3
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Venkatesh M, Awal SS. Hemiuterus with functional non-communicating horn in a young female. Egypt J Radiol Nucl Med 2021. [DOI: 10.1186/s43055-021-00507-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Abstract
Background
Mullerian duct anomalies are a broad spectrum of congenital anomalies of the female genital tract presenting with variable symptoms like infertility, amenorrhoea, dysmenorrhea, pelvic endometriosis, and poor obstetric outcomes. Unicornuate uterus or hemiuterus occurs as a result of abnormal formation or failure of formation of the contralateral part.
Case presentation
We present a rare case report of hemiuterus with functional non-communicating horn along with hematometra in a 15-year-old female who presented with severe dysmenorrhoea since her menarche. Pelvic Ultrasonography demonstrated inconclusive findings of a heterogenous lesion in the right pelvic cavity adjacent to the uterus. Further, pelvic MRI revealed a hemiuterus on the left side with a normal endometrial cavity and a well-defined functional non-communicating horn on right side. The diagnosis of European Society of Human Reproduction (ESHRE) Classification U4a uterine anomaly (left hemiuterus with functional non-communicating horn on right side) was established.
Conclusions
ESHRE Class U4a comprises of hemiuterus with a functional rudimentary horn. This is considered clinically significant as it may lead to further complications, such as hematometra or ectopic pregnancy in the rudimentary horn. Hence, the correct identification of this entity is essential as laparoscopic removal is the current recommended management.
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Shyamkumar S, Prabhu E, Ghosh S, Premalatha S, Lakshmigandhan I, Muthu Ambika T, Sree Rama Murthy A, Reshmi P, Venkatesh M, Clinsha P, Ravindranath NA, Suresh Kumar V, Mahendran K, Gnanasekar K, Ganesan R, Jayaraman V. Hydrogen sensors for comprehensive detection of steam leak in sodium-cooled fast reactors. Nuclear Engineering and Design 2021. [DOI: 10.1016/j.nucengdes.2021.111388] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Sheik Abdullah A, Selvakumar S, Venkatesh M. Assessment and evaluation of CHD risk factors using weighted ranked correlation and regression with data classification. Soft comput 2021. [DOI: 10.1007/s00500-021-05663-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Vishal Rao US, Arakeri G, Subash A, Venkatesh M, Brennan PA. Are carcinogens electron acceptors? A novel hypothesis. Med Hypotheses 2020; 144:110235. [PMID: 33201802 DOI: 10.1016/j.mehy.2020.110235] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2020] [Revised: 07/27/2020] [Accepted: 08/28/2020] [Indexed: 10/23/2022]
Abstract
Carcinogens play a key role in cancer initiation. Conventional theories support the concept of genetic changes inducing tumorigenesis through proteomics and metabolomics which lead to cancer development. Current research provides evidence that metabolic genes may be altered long before mutation of tumour suppressor genes, strongly suggesting that metabolic changes may be preceding the changes seen at a genetic level. Since cancer has long been known to occur through gene regulation, an impaired cellular respiration without utilizing mitochondrial function has been an area of active interest. We hypothesize the activity of carcinogens as electron acceptors to disrupt the normal glycolysis cycle happening in a cell by acting as positive ligands. The continuous restoration of NAD+ to cytosol by oxidation of NADH with carcinogen as electron acceptor creates a metabolic pathway to assist in the carcinogenic process. This metabolic pathway continues through an adaptive process, supplemented by pyruvate converting to lactate providing a constant pool of NAD+ to continue the glycolytic pathway. We also hypothesize that carcinogenesis occurs as a precursor to metabolic stress which may promote altered genetic and protein expression causing aberrant epigenetic and cell signaling pathways.
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Affiliation(s)
- U S Vishal Rao
- Dept of Head and Neck Oncology, HCG Cancer Hospital, Bengaluru, Karnataka, India
| | - Gururaj Arakeri
- Dept of Head and Neck Oncology, HCG Cancer Hospital, Bengaluru, Karnataka, India; Department of Oral and Maxillofacial Surgery, Navodaya Dental College and Hospital, Raichur, Karnataka, India.
| | - Anand Subash
- Dept of Head and Neck Oncology, HCG Cancer Hospital, Bengaluru, Karnataka, India
| | - M Venkatesh
- Dept of Head and Neck Oncology, HCG Cancer Hospital, Bengaluru, Karnataka, India
| | - Peter A Brennan
- Department of Oral & Maxillofacial Surgery, Queen Alexandra Hospital, Portsmouth, UK
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Kumari A, Chaudhary AK, Venkatesh M. Linear and nonlinear temperature-dependent transmission/absorption characteristics of cadmium telluride crystal for terahertz generation. Appl Opt 2020; 59:3417-3421. [PMID: 32400454 DOI: 10.1364/ao.366208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2019] [Accepted: 03/07/2020] [Indexed: 06/11/2023]
Abstract
This paper reports on the temperature-dependent investigation of linear and nonlinear transmission/absorption characteristics of CdTe crystal in the 300-408 K range using 780-970 nm tunable wavelengths of 140 fs pulses obtained from a Ti:Sapphire laser at 80 MHz repetition rate. The same pulses were also used for terahertz generation. The linear transmission/absorption properties were measured using a specially improvised temperature-tuned spectrophotometer in the 500-1500 nm wavelength range. The linear absorption of 750 nm wavelength gradually increases with respect to a rise in the temperature, and transmission becomes zero at 408 K. Nonlinear absorption induced by femtosecond pulses shows a sudden drop of 18% in transmission above the 800 nm range, due to electron-phonon interaction, which affects the strength of the terahertz signal. It is also responsible for change in the temperature along with the linear shift in the refractive index of the crystal.
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Saghafi H, Ayoub A, Naudi K, Venkatesh M, Kemp K. The impact of orthoganthic surgery on the quality of life, anxiety and depression. Int J Oral Maxillofac Surg 2019. [DOI: 10.1016/j.ijom.2019.03.393] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Venkatesh M, Gouthaman S, Kanemoto SO, Lakshmi MS, Hamerton I. Development of epoxy‐cyanate ester‐clay nanocomposites offering enhanced thermally stability. J Appl Polym Sci 2019. [DOI: 10.1002/app.47754] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- M. Venkatesh
- Polymer Science & Technology DivisionCentral Leather Research Institute (CSIR – CLRI) Chennai 600 020 India
| | - S. Gouthaman
- Polymer Science & Technology DivisionCentral Leather Research Institute (CSIR – CLRI) Chennai 600 020 India
| | - S. O. Kanemoto
- Polymer Science & Technology DivisionCentral Leather Research Institute (CSIR – CLRI) Chennai 600 020 India
- Macromolecular Research Team, Department of Inorganic ChemistryUniversity of Yaounde‐I, 812‐Yaounde Cameroon
| | - M. S. Lakshmi
- Polymer Science & Technology DivisionCentral Leather Research Institute (CSIR – CLRI) Chennai 600 020 India
| | - I. Hamerton
- Bristol Composites Institute (ACCIS), School of Civil, Aerospace, and Mechanical Engineering, Queen's BuildingUniversity of Bristol, University Walk Bristol BS8 1TR UK
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Agrawal A, Kumar VAK, Kiran NAS, Venkatesh M, Kumar VA. Noncontiguous two levels traumatic dislocation of the cervical spine managed with a posterior only approach. J Orthop Spine 2019. [DOI: 10.4103/joas.joas_36_19] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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11
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Damarla G, Venkatesh M, Chaudhary AK. Temperature-dependent terahertz spectroscopy and refractive index measurements of aqua-soluble and plastic explosives. Appl Opt 2018; 57:8743-8750. [PMID: 30461953 DOI: 10.1364/ao.57.008743] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Accepted: 09/11/2018] [Indexed: 06/09/2023]
Abstract
The paper reports the temperature-dependent time domain terahertz spectroscopy of premium aqua-soluble and plastic explosives such as NH4NO3, TNT, and RDX between 0.1 and 2.2 THz. Tunable terahertz radiation was generated using ZnTe crystal as a source, and a photoconductive antenna was used as a detector. The temperature-dependent study was carried out between 30°C and 200°C in a specially designed oven. The signature peaks of RDX and TNT present at 0.82 and 1.60 THz, respectively, show a strong redshift, whereas the NH4NO3 molecule shows a comparatively small shift. The high-temperature-based redshift phenomenon is just the opposite of the blueshift recorded at low temperatures. In addition, the temperature-dependent absorption coefficient data of these molecules support the change in the concentration of the NO2 molecule. We have also ascertained the temperature-dependent refractive indices of these molecules between 0.1 and 2.0 THz, which confirms the effect of temperature on the refractive indices. Finally, the signature peak of RDX with respect to the reduction in the weight concentration of RDX in the Teflon matrix was studied at 0.82 THz.
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Umamaheswara RV, Venkatesh M, Krishna S, Agrawal A. Acute subdural hematoma and subarachnoid hemorrhage associated with cerebral venous sinus thrombosis in apparently healthy individual. Ro J Neurol 2018. [DOI: 10.37897/rjn.2018.3.6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Affiliation(s)
- M Amuthabharathi
- Department of Radio-Diagnosis, Jawaharlal Institute of Postgraduate Medical Education and Research, Puducherry, India
| | - M Venkatesh
- Department of Radio-Diagnosis, Jawaharlal Institute of Postgraduate Medical Education and Research, Puducherry, India
| | - K Nagarajan
- Department of Radio-Diagnosis, Jawaharlal Institute of Postgraduate Medical Education and Research, Puducherry, India
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Ranjan P, Ramanathan AL, Kumar A, Singhal RK, Datta D, Venkatesh M. Trace metal distribution, assessment and enrichment in the surface sediments of Sundarban mangrove ecosystem in India and Bangladesh. Mar Pollut Bull 2018; 127:541-547. [PMID: 29475695 DOI: 10.1016/j.marpolbul.2017.11.047] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Revised: 11/17/2017] [Accepted: 11/22/2017] [Indexed: 06/08/2023]
Abstract
Comparative study of trace metals distribution in the surface sediment of Sundarban mangrove ecosystem in India and Bangladesh is one of the primary baseline study done so far. Trace metal distribution assessment covering lower salinity zone to higher salinity zone was done along Matla River (tidal river) in Indian side and freshwater zone to higher salinity zone along Passur River in Bangladesh side of Sundarban; representing anthropogenic influenced area, agricultural area, tourist site and pristine area. Trace metals distribution in the surface sediments of Sundarban mangrove ecosystem shows relatively higher value of trace metals, Co, Cr, Cu, Fe, Ni, Pb and Zn in Indian part when compared to Bangladesh. Enrichment factor shows the highest enrichment of Pb in both parts of Sundarban mangroves. Co, Cr, Cu, Pb and Zn show EF>1 indicates sediment contamination from anthropogenic activities. Cr, Ni and Pb were found to have moderate accumulation in geoaccumulation index with Fe showing high accumulation. Normalized data of trace metals shows 87.5% from Indian site and 80% of Bangladesh site as outlier, indicating anthropogenic influence. Out of total sampling site 50% of Indian and 40% of Bangladesh site show trace metal values enriched more than predicted value of trace metals indicating Indian part have more polluted sites than Bangladesh side of Sundarban, which is also confirmed by enrichment factor, I-geo and normalization values in both the sides.
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Affiliation(s)
- Prabhat Ranjan
- School of Environmental Sciences, Jawaharlal Nehru University, New Delhi, India.
| | - A L Ramanathan
- School of Environmental Sciences, Jawaharlal Nehru University, New Delhi, India.
| | - Alok Kumar
- Department of Environmental Science, Central University of Rajasthan, Kishangarh, Ajmer, Rajasthan, India.
| | - R K Singhal
- Analytical Chemistry Division, Bhabha Atomic Research Centre, Trombay, Mumbai, India.
| | - Dilip Datta
- Environmental Science Discipline, Khulna University, Khulna 9208, Bangladesh.
| | - M Venkatesh
- Analytical Chemistry Division, Bhabha Atomic Research Centre, Trombay, Mumbai, India.
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Thirupugalmani K, Venkatesh M, Karthick S, Maurya KK, Vijayan N, Chaudhary AK, Brahadeeswaran S. Influence of polar solvents on growth of potentially NLO active organic single crystals of N-benzyl-2-methyl-4-nitroaniline and their efficiency in terahertz generation. CrystEngComm 2017. [DOI: 10.1039/c7ce00228a] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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16
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Hall ES, Venkatesh M, Greenberg JM. A population study of first and subsequent pregnancy smoking behaviors in Ohio. J Perinatol 2016; 36:948-953. [PMID: 27467563 DOI: 10.1038/jp.2016.119] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Revised: 06/20/2016] [Accepted: 06/28/2016] [Indexed: 01/30/2023]
Abstract
OBJECTIVE The objective of this study is to identify maternal characteristics associated with non-smoking during a subsequent pregnancy after first pregnancy smoking. STUDY DESIGN We conducted a retrospective population-based analysis of Ohio vital birth records from 2007 to 2013. We used logistic regression to calculate adjusted odds ratios with 95% confidence intervals for detection of characteristics associated with non-smoking during a subsequent pregnancy after first pregnancy smoking. RESULTS Among 75 190 mothers, 75.6% were non-smokers and 13.7% were smokers during both pregnancies. During their first pregnancy, 49.7% of 15 075 smokers quit. Of them, 50.1% remained non-smokers during their subsequent pregnancy. Women who reduced, but continued smoking during their first pregnancy, were more than five times as likely to smoke during their subsequent pregnancy than women who quit (odds ratio (95% confidence interval): 2.85 (2.43 to 3.35) vs 0.55 (0.45 to 0.67)). CONCLUSION Interventions targeting complete cessation, rather than reduction in smoking among first-time mothers, may be the most effective at optimizing long-term health benefits.
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Affiliation(s)
- E S Hall
- Perinatal Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA.,Cradle Cincinnati, Cincinnati, OH, USA
| | | | - J M Greenberg
- Perinatal Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA.,Cradle Cincinnati, Cincinnati, OH, USA
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Abstract
AIM There are various therapeutic modalities of treatment for non-Hodgkin's lymphoma, but with certain limitations, hence, investigating the scope of combined therapeutic approach. MATERIALS AND METHODS In this article, cellular toxicity, apoptosis and expression of mitogen-activated protein kinase signaling pathway proteins were investigated in Raji cells preincubated with doxorubicin followed by (131)I-rituximab (rituximab radiolabeled with Iodine-131) treatment. RESULTS It was found that the (131)I-rituximab in combination with doxorubicin showed a higher amount of cell toxicity and apoptosis compared to respective controls. Expression of anti-apoptotic protein (B-cell lymphoma-extra-large) was downregulated and cleavage of poly (ADP-ribose) polymerase, a marker of apoptosis was higher in cells treated with doxorubicin (2 μg/mL) and 131 I-rituximab (P ≤ 0.05). Moreover, in these cells the basal level of expression of p42/44 and p38 were increased while its phosphorylation was decreased. CONCLUSION These results suggest that doxorubicin has the potential to sensitize (131)I-rituximab induced cell death in Raji cells.
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Affiliation(s)
| | | | - G Samuel
- Isotope Applications and Radiopharmaceuticals Division, Bhabha Atomic Research Centre, Mumbai, Maharashtra, India
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Datta J, Dasgupta S, Guin R, Venkatesh M, Suvarna S, Chowdhury DP. Determination of total arsenic and speciation of As(III) and As(V) in ground water by charged particle activation analysis. J Radioanal Nucl Chem 2015. [DOI: 10.1007/s10967-015-4571-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Rajesh K, Iniyavan P, Venkatesh M, Palakshi Reddy B, Balaji GL, Sarveswari S, Vijayakumar V. Regioselective synthesis of novel 2-chloroquinoline-based methyl 4-(4-hydroxyphenyl)-2-methyl-5-oxo-1,4,5,6,7,8-hexahydroquinoline-3-carboxylates. Res Chem Intermed 2015. [DOI: 10.1007/s11164-013-1275-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Venkatesh M, Mukherjee S, Wang H, Li H, Sun K, Benechet AP, Qiu Z, Maher L, Redinbo MR, Phillips RS, Fleet JC, Kortagere S, Mukherjee P, Fasano A, Le Ven J, Nicholson JK, Dumas ME, Khanna KM, Mani S. Symbiotic bacterial metabolites regulate gastrointestinal barrier function via the xenobiotic sensor PXR and Toll-like receptor 4. Immunity 2014; 41:296-310. [PMID: 25065623 DOI: 10.1016/j.immuni.2014.06.014] [Citation(s) in RCA: 607] [Impact Index Per Article: 60.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2013] [Accepted: 05/30/2014] [Indexed: 02/07/2023]
Abstract
Intestinal microbial metabolites are conjectured to affect mucosal integrity through an incompletely characterized mechanism. Here we showed that microbial-specific indoles regulated intestinal barrier function through the xenobiotic sensor, pregnane X receptor (PXR). Indole 3-propionic acid (IPA), in the context of indole, is a ligand for PXR in vivo, and IPA downregulated enterocyte TNF-α while it upregulated junctional protein-coding mRNAs. PXR-deficient (Nr1i2(-/-)) mice showed a distinctly "leaky" gut physiology coupled with upregulation of the Toll-like receptor (TLR) signaling pathway. These defects in the epithelial barrier were corrected in Nr1i2(-/-)Tlr4(-/-) mice. Our results demonstrate that a direct chemical communication between the intestinal symbionts and PXR regulates mucosal integrity through a pathway that involves luminal sensing and signaling by TLR4.
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Affiliation(s)
- Madhukumar Venkatesh
- Departments of Genetics and Medicine, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Subhajit Mukherjee
- Departments of Genetics and Medicine, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Hongwei Wang
- Departments of Genetics and Medicine, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Hao Li
- Departments of Genetics and Medicine, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Katherine Sun
- Department of Pathology, Montefiore Medical Center, Bronx, NY 10467, USA
| | - Alexandre P Benechet
- Department of Immunology, University of Connecticut Health Center, Farmington, CT 06030, USA
| | - Zhijuan Qiu
- Department of Immunology, University of Connecticut Health Center, Farmington, CT 06030, USA
| | - Leigh Maher
- Department of Immunology, University of Connecticut Health Center, Farmington, CT 06030, USA
| | - Matthew R Redinbo
- Department of Chemistry, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Robert S Phillips
- Department of Chemistry, University of Georgia, Athens, GA 30602, USA
| | - James C Fleet
- Department of Nutrition Science, Purdue University, West Lafayette, IN 47907, USA
| | - Sandhya Kortagere
- Department of Microbiology & Immunology, Drexel University College of Medicine, Philadelphia, PA 19129, USA
| | - Paromita Mukherjee
- Departments of Genetics and Medicine, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Alessio Fasano
- Department of Pediatrics, MassGeneral Hospital for Children, Harvard Medical School, Boston, MA 02114, USA
| | - Jessica Le Ven
- Section of Biomolecular Medicine, Division of Computational and Systems Medicine, Department of Surgery and Cancer, Faculty of Medicine, Imperial College London, Exhibition Road, South Kensington, London SW7 2AZ, UK
| | - Jeremy K Nicholson
- Section of Biomolecular Medicine, Division of Computational and Systems Medicine, Department of Surgery and Cancer, Faculty of Medicine, Imperial College London, Exhibition Road, South Kensington, London SW7 2AZ, UK
| | - Marc E Dumas
- Section of Biomolecular Medicine, Division of Computational and Systems Medicine, Department of Surgery and Cancer, Faculty of Medicine, Imperial College London, Exhibition Road, South Kensington, London SW7 2AZ, UK
| | - Kamal M Khanna
- Department of Immunology, University of Connecticut Health Center, Farmington, CT 06030, USA.
| | - Sridhar Mani
- Departments of Genetics and Medicine, Albert Einstein College of Medicine, Bronx, NY 10461, USA.
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Khanna K, Mukherjee S, Venkatesh M, Qiu Z, Mani S. Symbiotic bacterial metabolites regulate GI barrier function via PXR and TLR4 (MUC4P.852). The Journal of Immunology 2014. [DOI: 10.4049/jimmunol.192.supp.133.28] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Abstract
Intestinal microbial metabolites affect mucosal integrity through incompletely characterized mechanisms. Here we identify microbial specific indoles that regulate intestinal barrier function through the xenobiotic sensor, pregnane X receptor (PXR). Indole 3-propionic acid (IPA), in the context of indole, serves as a ligand for PXR and down-regulates enterocyte TNF-α while up-regulating junctional protein-coding mRNAs. Pxr-/- mice exhibit a distinctly “leaky” gut physiology coupled with up-regulation of the Toll-like receptor (TLR) signaling pathway. These defects in the epithelial barrier are corrected in Pxr-/-/Tlr4-/- double-knockout mice. To validate that IPA drives the anti-inflammatory response directly via PXR, we exposed intestinal commensal-depleted Pxr+/+ and Pxr-/- mice to live (IPA-producing) or heat-killed (non-IPA producing) C. sporogenes preceding indomethacin exposure (toxic small intestinal injury model). There was a significant reduction in histologic injury and mucosal myeloperoxidase (MPO) enzyme activity. The intestinal mucosa exposed to live (as opposed to heat-killed) C. sporogenes had significant induction of PXR target gene (Ugt1a1). These effects were absent in Pxr-/- mice. Our results demonstrate that a direct chemical communication between the intestinal symbionts and PXR regulates mucosal integrity through a pathway which involves luminal sensing and signaling by TLR4.
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Affiliation(s)
- Kamal Khanna
- 1Immunology, University of Connecticut Health Center, Farmington, CT
| | - Subhajit Mukherjee
- 2Departments of Genetics and Medicine, Albert Einstein College of Medicine, Bronx, NY
| | - Madhukumar Venkatesh
- 2Departments of Genetics and Medicine, Albert Einstein College of Medicine, Bronx, NY
| | - Zhijuan Qiu
- 1Immunology, University of Connecticut Health Center, Farmington, CT
| | - Sridhar Mani
- 2Departments of Genetics and Medicine, Albert Einstein College of Medicine, Bronx, NY
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Yadav J, Swapnil N, Venkatesh M, Prasad A. Studies directed toward the synthesis of caylobolide A: convergent synthesis of C21–C40 subunit. Tetrahedron Lett 2014. [DOI: 10.1016/j.tetlet.2013.12.091] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Balaji GL, Rajesh K, Venkatesh M, Sarveswari S, Vijayakumar V. Ultrasound-promoted synthesis of bi-, tri- and tetrapodal polyhydroquinolines, 1,4-dihydropyridines and the corresponding pyridines. RSC Adv 2014. [DOI: 10.1039/c3ra45138k] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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Venkatesh M, Gowda V. Synergistically acting PLA₂: peptide hemorrhagic complex from Daboia russelii venom. Toxicon 2013; 73:111-20. [PMID: 23872188 DOI: 10.1016/j.toxicon.2013.07.006] [Citation(s) in RCA: 10] [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: 03/26/2013] [Revised: 07/03/2013] [Accepted: 07/04/2013] [Indexed: 10/26/2022]
Abstract
Snake venoms are complex mixture of enzymatic and non-enzymatic proteins. Non-covalent protein-protein interaction leads to protein complexes, which bring about enhanced pharmacological injuries by their synergistic action. Here we report identification and characterization of a new Daboia russelii hemorrhagic complex I (DR-HC-I) containing phospholipase A₂ (PLA₂) and non-enzymatic peptide. DR-HC-I was isolated from the venom of D. russelii by CM-Shepadex-C25 and gel permeation chromatography. Individual components were purified and identified by RP-HPL chromatography, mass spectrometry and N-terminal amino acid sequencing. DR-HC-I complex was lethal to mice with the LD₅₀ dose of 0.7 mg/kg body weight with hemorrhagic and neurotoxic properties. DR-HC-I complex consists of non-hemorrhagic PLA₂ and neurotoxic non-enzymatic peptide. The non-enzymatic peptide quenched the intrinsic fluorescence of PLA₂ in a dose dependent manner, signifying the synergistic interaction between two proteins. PLA₂ and peptide toxin in a 5:2 M ratio induced skin hemorrhage in mice with MHD 20 μg. However, addition of ANS (1-Anilino-8-naphthalene sulfonate) to DR-HC-I complex inhibited skin hemorrhagic effect and also synergic interaction. But there was no impact on PLA₂ due to this synergistic interaction, and indirect hemolytic or plasma re-calcification activity. However, the synergistic interaction of PLA₂ and non-enzymatic peptide contributes to the enhanced venom-induced hemorrhage and toxicity of Daboia russellii venom.
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Affiliation(s)
- Madhukumar Venkatesh
- Department of Studies in Biochemistry, Manasagangotri, University of Mysore, Mysore 570006, Karnataka, India
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Venkatesh M, Ravi P, Tewari SP. Isoconversional Kinetic Analysis of Decomposition of Nitroimidazoles: Friedman method vs Flynn–Wall–Ozawa Method. J Phys Chem A 2013; 117:10162-9. [DOI: 10.1021/jp407526r] [Citation(s) in RCA: 140] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- M. Venkatesh
- Advanced Centre of
Research in High Energy Materials, University of Hyderabad, Hyderabad 500 046, India
| | - P. Ravi
- Advanced Centre of
Research in High Energy Materials, University of Hyderabad, Hyderabad 500 046, India
| | - Surya P. Tewari
- Advanced Centre of
Research in High Energy Materials, University of Hyderabad, Hyderabad 500 046, India
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Venkatesh M, Prasad N, Sing T, Gowda V. Purification, characterization, and chemical modification of neurotoxic peptide from Daboia russelii snake venom of India. J Biochem Mol Toxicol 2013; 27:295-304. [PMID: 23629951 DOI: 10.1002/jbt.21486] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [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: 01/29/2013] [Revised: 03/15/2013] [Accepted: 03/25/2013] [Indexed: 11/10/2022]
Abstract
Comprehensive knowledge of venom composition is very important for effective management of snake envenomation and antivenom preparation. Daboia russelii venom from the eastern region of India is the most neurotoxic among the four venom samples investigated. From the eastern D. russelii venom sample, neurotoxic peptide has been purified by combined method of ion exchange gel permeation chromatography and reversed phase high performance liquid chromatography. Molecular weight of Daboia neurotoxin III (DNTx-III) found to be 6,849 Da (as measured on matrix-assisted laser desorption/ionisation-time of flight mass spectrometer), and N-terminal amino acid sequences is I K C F I T P D U T S Q A. Approximate LD50 dosage was 0.24 mg/kg body weight. It produced concentration- and time-dependent inhibition of indirectly stimulated twitches of Rana hexadactyla sciatic nerve gastrocnemius muscle preparations. Chemical modification of DNTx-III tryptophan residue(s) reduced the twitch height inhibition property of toxin, signifying the importance of tryptophan residues for the neurotoxic function. This type of neurotoxic peptide is unique to east Indian regional D. russelii venom.
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Affiliation(s)
- Madhukumar Venkatesh
- Department of Studies in Biochemistry, University of Mysore, Mysore, 570 006, India
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Yadav J, Venkatesh M, Swapnil N, Prasad A. Toward the synthesis of tulearin C: stereoselective synthesis of the C1–C18 macrolactone core. Tetrahedron Lett 2013. [DOI: 10.1016/j.tetlet.2013.02.052] [Citation(s) in RCA: 4] [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: 10/27/2022]
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Li H, Redinbo MR, Venkatesh M, Ekins S, Chaudhry A, Bloch N, Negassa A, Mukherjee P, Kalpana G, Mani S. Novel yeast-based strategy unveils antagonist binding regions on the nuclear xenobiotic receptor PXR. J Biol Chem 2013; 288:13655-68. [PMID: 23525103 DOI: 10.1074/jbc.m113.455485] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [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: 01/09/2023] Open
Abstract
BACKGROUND Ketoconazole binds to and antagonizes pregnane X receptor (PXR) activation. RESULTS Yeast high throughput screens of PXR mutants define a unique region for ketoconazole binding. CONCLUSION Ketoconazole genetically interacts with specific PXR surface residues. SIGNIFICANCE A yeast-based genetic method to discover novel nuclear receptor interactions with ligands that associate with surface binding sites is suggested. The pregnane X receptor (PXR) is a master regulator of xenobiotic metabolism, and its activity is critical toward understanding the pathophysiology of several diseases, including inflammation, cancer, and steatosis. Previous studies have demonstrated that ketoconazole binds to ligand-activated PXR and antagonizes receptor control of gene expression. Structure-function as well as computational docking analysis suggested a putative binding region containing critical charge clamp residues Gln-272, and Phe-264 on the AF-2 surface of PXR. To define the antagonist binding surface(s) of PXR, we developed a novel assay to identify key amino acid residues on PXR based on a yeast two-hybrid screen that examined mutant forms of PXR. This screen identified multiple "gain-of-function" mutants that were "resistant" to the PXR antagonist effects of ketoconazole. We then compared our screen results identifying key PXR residues to those predicted by computational methods. Of 15 potential or putative binding residues based on docking, we identified three residues in the yeast screen that were then systematically verified to functionally interact with ketoconazole using mammalian assays. Among the residues confirmed by our study was Ser-208, which is on the opposite side of the protein from the AF-2 region critical for receptor regulation. The identification of new locations for antagonist binding on the surface or buried in PXR indicates novel aspects to the mechanism of receptor antagonism. These results significantly expand our understanding of antagonist binding sites on the surface of PXR and suggest new avenues to regulate this receptor for clinical applications.
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Affiliation(s)
- Hao Li
- Department of Medicine, Albert Einstein College of Medicine, Bronx, New York 10461, USA
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Dou W, Mukherjee S, Li H, Venkatesh M, Wang H, Kortagere S, Peleg A, Chilimuri SS, Wang ZT, Feng Y, Fearon ER, Mani S. Alleviation of gut inflammation by Cdx2/Pxr pathway in a mouse model of chemical colitis. PLoS One 2012; 7:e36075. [PMID: 22815676 PMCID: PMC3398007 DOI: 10.1371/journal.pone.0036075] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.5] [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: 02/14/2012] [Accepted: 03/25/2012] [Indexed: 01/10/2023] Open
Abstract
Pregnane X Receptor (PXR), a master regulator of drug metabolism and inflammation, is abundantly expressed in the gastrointestinal tract. Baicalein and its O-glucuronide baicalin are potent anti-inflammatory and anti-cancer herbal flavonoids that undergo a complex cycle of interconversion in the liver and gut. We sought to investigate the role these flavonoids play in inhibiting gut inflammation by an axis involving PXR and other potential factors. The consequences of PXR regulation and activation by the herbal flavonoids, baicalein and baicalin were evaluated in vitro in human colon carcinoma cells and in vivo using wild-type, Pxr-null, and humanized (hPXR) PXR mice. Baicalein, but not its glucuronidated metabolite baicalin, activates PXR in a Cdx2-dependent manner in vitro, in human colon carcinoma LS174T cells, and in the murine colon in vivo. While both flavonoids abrogate dextran sodium sulfate (DSS)-mediated colon inflammation in vivo, oral delivery of a potent bacterial β-glucuronidase inhibitor eliminates baicalin’s effect on gastrointestinal inflammation by preventing the microbial conversion of baicalin to baicalien. Finally, reduction of gastrointestinal inflammation requires the binding of Cdx2 to a specific proximal site on the PXR promoter. Pharmacological targeting of intestinal PXR using natural metabolically labile ligands could serve as effective and potent therapeutics for gut inflammation that avert systemic drug interactions.
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Affiliation(s)
- Wei Dou
- Departments of Medicine and Genetics, Albert Einstein College of Medicine, New York, New York, United States of America
- Shanghai Key Laboratory of Formulated Chinese Medicines and MOE Key Laboratory for Standardization Chinese Medicine, Institute of Chinese Materia Medica, Shanghai University of TCM, Shanghai, China
| | - Subhajit Mukherjee
- Departments of Medicine and Genetics, Albert Einstein College of Medicine, New York, New York, United States of America
| | - Hao Li
- Departments of Medicine and Genetics, Albert Einstein College of Medicine, New York, New York, United States of America
| | - Madhukumar Venkatesh
- Departments of Medicine and Genetics, Albert Einstein College of Medicine, New York, New York, United States of America
| | - Hongwei Wang
- Departments of Medicine and Genetics, Albert Einstein College of Medicine, New York, New York, United States of America
| | - Sandhya Kortagere
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania, United States of America
| | - Ariel Peleg
- Departments of Medicine and Genetics, Albert Einstein College of Medicine, New York, New York, United States of America
| | - Sridhar S. Chilimuri
- Department of Medicine, Bronx Lebanon Hospital Center, Bronx, New York, United States of America
| | - Zheng-Tao Wang
- Shanghai Key Laboratory of Formulated Chinese Medicines and MOE Key Laboratory for Standardization Chinese Medicine, Institute of Chinese Materia Medica, Shanghai University of TCM, Shanghai, China
- Institute of Chinese Materia Medica, Shanghai University of TCM, Shanghai, China
- * E-mail: (ZW); (SM)
| | - Ying Feng
- Division of Molecular Medicine and Genetics, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, Michigan
| | - Eric R. Fearon
- Division of Molecular Medicine and Genetics, Department of Internal Medicine, Human Genetics and Pathology, University of Michigan Medical School, Ann Arbor, Michigan, United States of America
| | - Sridhar Mani
- Departments of Medicine and Genetics, Albert Einstein College of Medicine, New York, New York, United States of America
- * E-mail: (ZW); (SM)
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Pandit S, Mukherjee PK, Mukherjee K, Gajbhiye R, Venkatesh M, Ponnusankar S, Bhadra S. Cytochrome P450 inhibitory potential of selected Indian spices — possible food drug interaction. Food Res Int 2012. [DOI: 10.1016/j.foodres.2011.08.021] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Mukherjee PK, Satheeshkumar N, Venkatesh P, Venkatesh M. Lead finding for acetyl cholinesterase inhibitors from natural origin: structure activity relationship and scope. Mini Rev Med Chem 2011; 11:247-62. [PMID: 21222577 DOI: 10.2174/138955711795049880] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2010] [Accepted: 01/05/2011] [Indexed: 11/22/2022]
Abstract
Acetylcholinesterase (AChE) inhibitors are considered as promising therapeutic agents for the treatment of several neurological disorders such as Alzheimer's disease (AD), senile dementia, ataxia and myasthenia gravis. There are only few synthetic medicines with adverse effects, available for treatment of cognitive dysfunction and memory loss associated with these diseases. A variety of plants has been reported to possess AChE inhibitory activity and so may be relevant to the treatment of neurodegenerative disorders such as AD. Hence, developing potential AChE inhibitors from botanicals is the need of the day. This review will cover some of the promising acetylcholinesterase inhibitors isolated from plants with proven in vitro and in vivo activities with concern to their structure activity relationship.
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Affiliation(s)
- P K Mukherjee
- School of Natural Product Studies, Dept. of Pharmaceutical Technology, Jadavpur University, Kolkata 700032, India.
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Wang H, Venkatesh M, Li H, Goetz R, Mukherjee S, Biswas A, Zhu L, Kaubisch A, Wang L, Pullman J, Whitney K, Kuro-o M, Roig AI, Shay JW, Mohammadi M, Mani S. Pregnane X receptor activation induces FGF19-dependent tumor aggressiveness in humans and mice. J Clin Invest 2011; 121:3220-32. [PMID: 21747170 DOI: 10.1172/jci41514] [Citation(s) in RCA: 107] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2010] [Accepted: 05/18/2011] [Indexed: 01/10/2023] Open
Abstract
The nuclear receptor pregnane X receptor (PXR) is activated by a range of xenochemicals, including chemotherapeutic drugs, and has been suggested to play a role in the development of tumor cell resistance to anticancer drugs. PXR also has been implicated as a regulator of the growth and apoptosis of colon tumors. Here, we have used a xenograft model of colon cancer to define a molecular mechanism that might underlie PXR-driven colon tumor growth and malignancy. Activation of PXR was found to be sufficient to enhance the neoplastic characteristics, including cell growth, invasion, and metastasis, of both human colon tumor cell lines and primary human colon cancer tissue xenografted into immunodeficient mice. Furthermore, we were able to show that this PXR-mediated phenotype required FGF19 signaling. PXR bound to the FGF19 promoter in both human colon tumor cells and "normal" intestinal crypt cells. However, while both cell types proliferated in response to PXR ligands, the FGF19 promoter was activated by PXR only in cancer cells. Taken together, these data indicate that colon cancer growth in the presence of a specific PXR ligand results from tumor-specific induction of FGF19. These observations may lead to improved therapeutic regimens for colon carcinomas.
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Affiliation(s)
- Hongwei Wang
- Albert Einstein Cancer Center, Albert Einstein College of Medicine, New York, New York 10461, USA
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Fun HK, Hemamalini M, Venkat Ragavan R, Vijayakumar V, Venkatesh M. 1,1′-Bis(4-fluorophenyl)-3,3′-diisobutyl-4,4′-diphenoxy-1 H,1′ H-4,4′-bipyrazole-5,5′(4 H,4′ H)-dione. Acta Crystallogr Sect E Struct Rep Online 2011; 67:o1036. [PMID: 21754364 PMCID: PMC3089260 DOI: 10.1107/s1600536811011664] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2011] [Accepted: 03/29/2011] [Indexed: 11/10/2022]
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Mukherjee K, Venkatesh M, Venkatesh P, Saha B, Mukherjee PK. Effect of soy phosphatidyl choline on the bioavailability and nutritional health benefits of resveratrol. Food Res Int 2011. [DOI: 10.1016/j.foodres.2011.03.034] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Venkatesh M, Wang H, Cayer J, Leroux M, Salvail D, Das B, Wrobel JE, Mani S. In vivo and in vitro characterization of a first-in-class novel azole analog that targets pregnane X receptor activation. Mol Pharmacol 2011; 80:124-35. [PMID: 21464197 DOI: 10.1124/mol.111.071787] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The pregnane X receptor (PXR) is a master regulator of xenobiotic clearance and is implicated in deleterious drug interactions (e.g., acetaminophen hepatotoxicity) and cancer drug resistance. However, small-molecule targeting of this receptor has been difficult; to date, directed synthesis of a relatively specific PXR inhibitor has remained elusive. Here we report the development and characterization of a first-in-class novel azole analog [1-(4-(4-(((2R,4S)-2-(2,4-difluorophenyl)-2-methyl-1,3-dioxolan-4-yl)methoxy)phenyl)piperazin-1-yl)ethanone (FLB-12)] that antagonizes the activated state of PXR with limited effects on other related nuclear receptors (i.e., liver X receptor, farnesoid X receptor, estrogen receptor α, peroxisome proliferator-activated receptor γ, and mouse constitutive androstane receptor). We investigated the toxicity and PXR antagonist effect of FLB-12 in vivo. Compared with ketoconazole, a prototypical PXR antagonist, FLB-12 is significantly less toxic to hepatocytes. FLB-12 significantly inhibits the PXR-activated loss of righting reflex to 2,2,2-tribromoethanol (Avertin) in vivo, abrogates PXR-mediated resistance to 7-ethyl-10-hydroxycamptothecin (SN-38) in colon cancer cells in vitro, and attenuates PXR-mediated acetaminophen hepatotoxicity in vivo. Thus, relatively selective targeting of PXR by antagonists is feasible and warrants further investigation. This class of agents is suitable for development as chemical probes of PXR function as well as potential PXR-directed therapeutics.
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Affiliation(s)
- Madhukumar Venkatesh
- Albert Einstein Cancer Center, Albert Einstein College of Medicine, New York, New York, USA
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Shahani T, Fun HK, Ragavan RV, Vijayakumar V, Venkatesh M. 5-Ethyl-2-(4-fluoro-phen-yl)-4-phen-oxy-1H-pyrazol-3(2H)-one. Acta Crystallogr Sect E Struct Rep Online 2011; 67:o475. [PMID: 21523133 PMCID: PMC3051690 DOI: 10.1107/s1600536811000754] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2011] [Accepted: 01/06/2011] [Indexed: 11/16/2022]
Abstract
In the title compound, C17H15FN2O2, the essentially planar pyrazole ring [maximum deviation = 0.026 (1) Å] makes dihedral angles of 72.06 (7) and 33.05 (7)°, with the phenyl and fluorobenzene rings, respectively. The dihedral angle between the two six-membered rings is 87.88 (7)°. In the crystal, intermolecular N—H⋯O and C—H⋯F hydrogen bonds link the molecules into layers lying parallel to the bc plane.
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Loh WS, Fun HK, Ragavan RV, Vijayakumar V, Venkatesh M. 5-Ethyl-4-phenyl-1H-pyrazol-3(2H)-one. Acta Crystallogr Sect E Struct Rep Online 2011; 67:o403-o404. [PMID: 21523076 PMCID: PMC3051742 DOI: 10.1107/s1600536811001589] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2010] [Accepted: 01/11/2011] [Indexed: 05/30/2023]
Abstract
The asymmetric unit of the title compound, C(11)H(12)N(2)O, consists of two crystallographically independent mol-ecules (A and B) with similar geometries. Both mol-ecules exist in a keto form, the C=O bond length being 1.286 (2) Å in A and 1.283 (2) Å in B. The dihedral angles between the pyrazole ring and the attached phenyl ring are 43.28 (12) and 46.88 (11)°, respectively, for A and B. The ethyl unit in mol-ecule B is disordered over two positions with a site-occupancy ratio of 0.508 (5):0.492 (5). In the crystal, each of the independent mol-ecules forms a centrosymmetric dimer with an R(2) (2)(8) ring motif through a pair of N-H⋯O hydrogen bonds. These dimers are further connected into a three-dimensional network by inter-molecular N-H⋯O and C-H⋯O hydrogen bonds. Inter-molecular C-H⋯π inter-actions are also present.
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Affiliation(s)
- Wan-Sin Loh
- X-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia
| | - Hoong-Kun Fun
- X-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia
| | - R. Venkat Ragavan
- Organic Chemistry Division, School of Advanced Sciences, VIT University, Vellore 632 014, India
| | - V. Vijayakumar
- Organic Chemistry Division, School of Advanced Sciences, VIT University, Vellore 632 014, India
| | - M. Venkatesh
- Organic Chemistry Division, School of Advanced Sciences, VIT University, Vellore 632 014, India
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Venkatesh M, Bairavi VG, Sasikumar KC. Generic antibiotic industries: Challenges and implied strategies with regulatory perspectives. J Pharm Bioallied Sci 2011; 3:101-8. [PMID: 21430959 PMCID: PMC3053506 DOI: 10.4103/0975-7406.76481] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2010] [Revised: 11/10/2010] [Accepted: 12/09/2010] [Indexed: 11/04/2022] Open
Abstract
Ever since the discovery of antibiotics, the quality of human life greatly improved in the 20(th) century. The discovery of penicillin transformed the medicine industry and initiated a search for a better antibiotic every time resulting in several synthetic and semi-synthetic antibiotics. Beginning with the 1937 sulfa drug tragedy, the drug regulations had a parallel growth along with the antibiotics and the antibiotic-based generic Pharma industries. This review article is focused on the scenario depicting current global Pharma industries based on generic antibiotics. Several regulatory aspects involved with these industries have been discussed along with the complexity of the market, issues that could affect their growth, their struggle for quality, and their compliance with the tightened regulations. With the skyrocketing commercialization of antibiotics through generics and the leveraging technologic renaissance, generic industries are involved in providing maximum safer benefits for the welfare of the people, highlighting its need today..
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Affiliation(s)
- M. Venkatesh
- Regulatory Affairs, Orchid Chemicals & Pharmaceuticals Ltd., 313, Valluvar Kottam High Road, Chennai - 600 034, India
| | - V. G. Bairavi
- Regulatory Affairs, Orchid Chemicals & Pharmaceuticals Ltd., 313, Valluvar Kottam High Road, Chennai - 600 034, India
| | - K. C. Sasikumar
- Regulatory Affairs, Orchid Chemicals & Pharmaceuticals Ltd., 313, Valluvar Kottam High Road, Chennai - 600 034, India
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Ponnusankar S, Pandit S, Venkatesh M, Bandyopadhyay A, Mukherjee PK. Cytochrome P450 Inhibition Assay for Standardized Extract of Terminalia chebula
Retz. Phytother Res 2010; 25:151-4. [DOI: 10.1002/ptr.2993] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Wallace BD, Wang H, Lane KT, Scott JE, Orans J, Koo JS, Venkatesh M, Jobin C, Yeh LA, Mani S, Redinbo MR. Alleviating cancer drug toxicity by inhibiting a bacterial enzyme. Science 2010; 330:831-5. [PMID: 21051639 DOI: 10.1126/science.1191175] [Citation(s) in RCA: 685] [Impact Index Per Article: 48.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The dose-limiting side effect of the common colon cancer chemotherapeutic CPT-11 is severe diarrhea caused by symbiotic bacterial β-glucuronidases that reactivate the drug in the gut. We sought to target these enzymes without killing the commensal bacteria essential for human health. Potent bacterial β-glucuronidase inhibitors were identified by high-throughput screening and shown to have no effect on the orthologous mammalian enzyme. Crystal structures established that selectivity was based on a loop unique to bacterial β-glucuronidases. Inhibitors were highly effective against the enzyme target in living aerobic and anaerobic bacteria, but did not kill the bacteria or harm mammalian cells. Finally, oral administration of an inhibitor protected mice from CPT-11-induced toxicity. Thus, drugs may be designed to inhibit undesirable enzyme activities in essential microbial symbiotes to enhance chemotherapeutic efficacy.
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Affiliation(s)
- Bret D Wallace
- Department of Chemistry, University of North Carolina, Chapel Hill, NC 27599, USA
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Shahani T, Fun HK, Ragavan RV, Vijayakumar V, Venkatesh M. 1-{[5-(4-Chloro-phen-yl)-1-(4-fluoro-phen-yl)-1H-pyrazol-3-yl]carbon-yl]}piperidin-4-one. Acta Crystallogr Sect E Struct Rep Online 2010; 66:o3233-4. [PMID: 21589523 PMCID: PMC3011612 DOI: 10.1107/s1600536810047215] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2010] [Accepted: 11/15/2010] [Indexed: 11/25/2022]
Abstract
In the title compound, C21H17ClFN3O2, the 1H-pyrazole ring makes dihedral angles of 36.73 (7), 18.73 (7) and 60.88 (8)°, respectively, with the mean planes of the chlorophenyl, 4-oxopiperidine and fluorophenyl rings. The molecular structure is stabilized by an intramolecular C—H⋯N hydrogen bond, which forms an S(6) ring motif. In the crystal, intermolecular C—H⋯O hydrogen bonds link molecules into chains along [101]. In addition, intermolecular C—H⋯F hydrogen bonds with an R21(7) ring motif connect neighbouring chains into layers parallel to the ac plane.
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Loh WS, Fun HK, Ragavan RV, Vijayakumar V, Venkatesh M. 5-Isobutyl-4-phenyl-sulfonyl-1H-pyrazol-3(2H)-one. Acta Crystallogr Sect E Struct Rep Online 2010; 66:o3050-1. [PMID: 21589363 PMCID: PMC3011737 DOI: 10.1107/s1600536810044181] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2010] [Accepted: 10/28/2010] [Indexed: 11/18/2022]
Abstract
The title compound, C13H16N2O3S, consists of two crystallographically independent molecules with similar geometries and exists in a keto form, the C=O bond lengths being 1.267 (2) and 1.254 (2) Å. In both molecules, the pyrazole rings are approximately planar, with maximum deviations of 0.017 (2) and 0.010 (2) Å, and the dihedral angles between the pyrazole and phenyl rings are 83.63 (11) and 70.07 (12)°. In one molecule, an intramolecular C—H⋯O hydrogen bond with an S(6) ring motif is observed. In the crystal, intermolecular N—H⋯O and C—H⋯O hydrogen bonds link the molecules into two-dimensional networks parallel to the ab plane.
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Wallace BD, Wang H, Lane KT, Scott JE, Orans J, Koo JS, Venkatesh M, Jobin C, Yeh LA, Mani S, Redinbo MR. Alleviating cancer drug toxicity by inhibiting a bacterial enzyme. Science 2010; 330:831-835. [PMID: 21051639 PMCID: PMC3110694 DOI: 10.1126/science.1191175;pmid:21051639] [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] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The dose-limiting side effect of the common colon cancer chemotherapeutic CPT-11 is severe diarrhea caused by symbiotic bacterial β-glucuronidases that reactivate the drug in the gut. We sought to target these enzymes without killing the commensal bacteria essential for human health. Potent bacterial β-glucuronidase inhibitors were identified by high-throughput screening and shown to have no effect on the orthologous mammalian enzyme. Crystal structures established that selectivity was based on a loop unique to bacterial β-glucuronidases. Inhibitors were highly effective against the enzyme target in living aerobic and anaerobic bacteria, but did not kill the bacteria or harm mammalian cells. Finally, oral administration of an inhibitor protected mice from CPT-11-induced toxicity. Thus, drugs may be designed to inhibit undesirable enzyme activities in essential microbial symbiotes to enhance chemotherapeutic efficacy.
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Affiliation(s)
- Bret D. Wallace
- Department of Chemistry, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Hongwei Wang
- Departments of Medicine, Oncology and Genetics, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Kimberly T. Lane
- Department of Chemistry, University of North Carolina, Chapel Hill, NC 27599, USA
| | - John E. Scott
- Biomanufacturing Research Institute and Technology Enterprise (BRITE), North Carolina Central University, Durham, NC 27707, USA
| | - Jillian Orans
- Department of Chemistry, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Ja Seol Koo
- Department of Medicine, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Madhukumar Venkatesh
- Departments of Medicine, Oncology and Genetics, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Christian Jobin
- Department of Medicine, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Li-An Yeh
- Biomanufacturing Research Institute and Technology Enterprise (BRITE), North Carolina Central University, Durham, NC 27707, USA
| | - Sridhar Mani
- Departments of Medicine, Oncology and Genetics, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Matthew R. Redinbo
- Department of Chemistry, University of North Carolina, Chapel Hill, NC 27599, USA
- Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill, NC 27599, USA
- Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC 27599, USA
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Shahani T, Fun HK, Ragavan RV, Vijayakumar V, Venkatesh M. 1-(4-Fluoro-phen-yl)-3-methyl-4-phenyl-sulfanyl-1H-pyrazol-5(4H)-one. Acta Crystallogr Sect E Struct Rep Online 2010; 66:o2815-6. [PMID: 21589006 PMCID: PMC3009262 DOI: 10.1107/s1600536810040596] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2010] [Accepted: 10/10/2010] [Indexed: 11/14/2022]
Abstract
The title compound, C16H13FN2OS, has undergone enol-to-keto tautomerism during the crystallization process. The 1H-pyrazole-5-one ring [maximum deviation = 0.0198 (11) Å] is inclined at angles of 33.10 (5) and 79.57 (5)° with respect to the fluorophenyl [maximum deviation = 0.0090 (12) Å] and phenylthiol [maximum deviation = 0.0229 (3) Å] rings attached to it. In the crystal, neighbouring molecules are linked into inversion dimers, generating R22(8) ring motifs. These dimers are further linked into two-dimensional arrays parallel to the bc plane via intermolecular N—H⋯O, C—H⋯F and C—H⋯O hydrogen bonds. The crystal is further stabilized by weak π–π [centroid–centroid distance = 3.6921 (7) Å] and C—H⋯π interactions.
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Kortagere S, Krasowski MD, Reschly EJ, Venkatesh M, Mani S, Ekins S. Evaluation of computational docking to identify pregnane X receptor agonists in the ToxCast database. Environ Health Perspect 2010; 118:1412-1417. [PMID: 20558333 PMCID: PMC2957921 DOI: 10.1289/ehp.1001930] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/12/2010] [Accepted: 06/17/2010] [Indexed: 05/29/2023]
Abstract
BACKGROUND The pregnane X receptor (PXR) is a key transcriptional regulator of many genes [e.g., cytochrome P450s (CYP2C9, CYP3A4, CYP2B6), MDR1] involved in xenobiotic metabolism and excretion. OBJECTIVES As part of an evaluation of different approaches to predict compound affinity for nuclear hormone receptors, we used the molecular docking program GOLD and a hybrid scoring scheme based on similarity weighted GoldScores to predict potential PXR agonists in the ToxCast database of pesticides and other industrial chemicals. We present some of the limitations of different in vitro systems, as well as docking and ligand-based computational models. METHODS Each ToxCast compound was docked into the five published crystallographic structures of human PXR (hPXR), and 15 compounds were selected based on their consensus docking scores for testing. In addition, we used a Bayesian model to classify the ToxCast compounds into PXR agonists and nonagonists. hPXR activation was determined by luciferase-based reporter assays in the HepG2 and DPX-2 human liver cell lines. RESULTS We tested 11 compounds, of which 6 were strong agonists and 2 had weak agonist activity. Docking results of additional compounds were compared with data reported in the literature. The prediction sensitivity of PXR agonists in our sample ToxCast data set (n = 28) using docking and the GoldScore was higher than with the hybrid score at 66.7%. The prediction sensitivity for PXR agonists using GoldScore for the entire ToxCast data set (n = 308) compared with data from the NIH (National Institutes of Health) Chemical Genomics Center data was 73.8%. CONCLUSIONS Docking and the GoldScore may be useful for prioritizing large data sets prior to in vitro testing with good sensitivity across the sample and entire ToxCast data set for hPXR agonists.
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Affiliation(s)
- Sandhya Kortagere
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania, USA
| | - Matthew D. Krasowski
- Department of Pathology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Erica J. Reschly
- Department of Pathology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Madhukumar Venkatesh
- Albert Einstein Cancer Center, Albert Einstein College of Medicine, Bronx, New York, USA
| | - Sridhar Mani
- Albert Einstein Cancer Center, Albert Einstein College of Medicine, Bronx, New York, USA
| | - Sean Ekins
- Collaborations in Chemistry, Jenkintown, Pennsylvania, USA
- Department of Pharmaceutical Sciences, University of Maryland, Baltimore, Maryland, USA
- Department of Pharmacology, Robert Wood Johnson Medical School, University of Medicine and Dentistry of New Jersey, Piscataway, New Jersey, USA
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Loh WS, Fun HK, Ragavan RV, Vijayakumar V, Venkatesh M. 4-{[5-(4-Chloro-phen-yl)-1-(4-fluoro-phen-yl)-1H-pyrazol-3-yl]carbon-yl}-N-(4-cyano-phen-yl)piperazine-1-carboxamide. Acta Crystallogr Sect E Struct Rep Online 2010; 66:o2563-4. [PMID: 21587549 PMCID: PMC2983346 DOI: 10.1107/s1600536810036159] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2010] [Accepted: 09/08/2010] [Indexed: 11/10/2022]
Abstract
In the title compound, C(28)H(22)ClFN(6)O(2), the piperazine ring adopts a chair conformation and the least-squares plane through the four coplanar atoms forms dihedral angles of 69.37 (13) and 56.56 (12)°, respectively, with the pyrazole and cyano-phenyl rings. The dihedral angles formed between the pyrazole and the attached fluoro- and chloro-phenyl rings are 34.16 (10) and 73.27 (12)°, respectively. In the crystal, inter-molecular N-H⋯O, C-H⋯N and C-H⋯O hydrogen bonds link the mol-ecules into sheets parallel to the ac plane.
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Yadav J, Thrimurtulu N, Venkatesh M, Prasad A. The Stereoselective Total Synthesis of Aculeatin A and B via Prins Cyclization. SYNTHESIS-STUTTGART 2009. [DOI: 10.1055/s-0029-1217144] [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: 10/20/2022]
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Yadav J, Thrimurtulu N, Venkatesh M, Rao K, Prasad A, Reddy B. Stereoselective Synthesis of (10S,12S)-10-Hydroxy-12-methyl-1-oxacyclododecane-2,5-dione via Prins Cyclization. SYNTHESIS-STUTTGART 2009. [DOI: 10.1055/s-0029-1217107] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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