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Akram S, Ashfaq T, Saeed Z, Ashraf R, Mushtaq M. Effect of slow-release amylase on extraction of peach peel phenolics and their antioxidant activities. AAlim 2022. [DOI: 10.1556/066.2022.00110] [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: 11/19/2022]
Abstract
Abstract
The present manuscript demonstrates the work undertaken to optimise and validate a slow-release amylase-assisted extraction of polyphenols from peach fruit peel. A careful investigation and optimisation revealed that peach peel when hydrolysed with 1.50% (w/w) of SRA containing enzyme formulation at 40 °C and 6.1 pH, for 35 min significantly (P < 0.05) increased the extraction yield, levels of polyphenol contents (242.89 ± 1.56 mg gallic acid equivalents – GAE), and coumaric, chlorogenic, ferulic acids or their conjugate esters in extracts. Moreover, the extracts produced through SRA-assisted extraction exhibited ample level of free radical scavenging capacity (DPPH IC50 2.67 ± 0.03 μg mL−1), Trolox equivalent (TE) antioxidant capacity (450.52 ± 24.58 µmol of TE g−1), inhibition of peroxides in linoleic acid (85.68 ± 0.21%), and ferric reducing power of 3.11 ± 0.20 ppm gallic acid equivalents. The results suggested that the incorporation of SRA containing enzyme formulation may enhance the recovery of peach peel polyphenols while hydrolysing the glycosidic linkages without deteriorating their antioxidant character.
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Affiliation(s)
- S. Akram
- Division of Science and Technology, University of Education, Lahore, Pakistan
| | - T. Ashfaq
- Department of Chemistry, Kinnaird College for Women, Lahore, Pakistan
| | - Z. Saeed
- Department of Chemistry, GC University, Lahore, Pakistan
| | - R. Ashraf
- Department of Chemistry, University of Agriculture, Faisalabad, Pakistan
| | - M. Mushtaq
- Department of Chemistry, GC University, Lahore, Pakistan
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Mushtaq M, Ishtiak-Ahmed K, Thirstrup J, Gasse C. Pharmacogenetics and antidepressant treatment outcomes in pregnancy: a Danish-population based study. Eur Psychiatry 2022. [PMCID: PMC9567066 DOI: 10.1192/j.eurpsy.2022.297] [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] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Introduction
Depression in pregnancy is common and often requires treatment with antidepressant drugs. Most antidepressants are metabolized by the cytochrome P450 system (CYP), in particular CYP2C19 and -2D6, both of which are genetically polymorphic. Additionally, the activity of these enzymes is altered during pregnancy.
Objectives
To investigate pharmacogenetic variability regarding CYP2C19 and -2D6 in pregnant users of antidepressants and treatment outcomes.
Methods
The study population comprises all women born between 1981-1999, who gave birth to at least one child before December 2015 identified from the large Danish population-based iPSYCH2012 case-cohort study sample linked to information on genetic variants, prescription drug use and outcome data. Pharmacogenetic genotypes and phenotypes of CYP2C19 and CYP2D6 will be categorized into poor, (PM), intermediate, (IM), extensive, (EM), rapid (RM) and ultra-rapid metabolizers (RM) using array-based SNP information. Antidepressant drug use and comedication during pregnancy will be assessed based on prescription data. Outcomes include treatment discontinuation, switching and psychiatric hospitalizations. Cox regression analysis will be performed to estimate the hazard ratios comparing the rates of the different outcomes in people with different phenotypes, compared with EM adjusted for a number of confounding factors.
Results
Based on previous research we will be able to identify approximately 6531 pregnant women with a psychiatric history. Among those, we estimate to find 14 PM, 161 IM, 285 EM, 168 RM and 25 UM of CYP2C19, and 27 PM, 218 IM and 408 EM of CYP2D6. Exposure to antidepressants is estimated at 10%.
Conclusions
We expect to be able to present the results at the conference.
Disclosure
No significant relationships.
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Mushtaq M, Bukhari SM, Ahmad S, Khattak A, Chattha MB, Mubeen I, Rehman KU, Andleeb S, Hussain S, Javid A, Hussain A, Ali W, Khalid N, Mustafa G, Sughra F, Iqbal MJ, Khalid M, Naeem MM, Inayat M. Isolation and characterization of bacteria residing in the oral, gut, and fecal samples of different pheasant species. BRAZ J BIOL 2021; 83:e249159. [PMID: 34586192 DOI: 10.1590/1519-6984.249159] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Accepted: 05/19/2021] [Indexed: 11/21/2022] Open
Abstract
There is a paucity of research conducted on microbial prevalence in pheasants. The microbiota of captive birds has zoonotic significance and must be characterize. Present study is therefore planned to assess the microbiota from oral, fecal and gut content of captive avian species. It will be helpful in characterization of harmful microbes. Different samples taken from oral, gut and feces of ring-necked pheasants (Phasianus colchicus), green pheasants (Phasianus versicolor), golden pheasant (Chrysolophus pictus) and silver pheasant (Lophura nycthemera). Samples were collected, diluted, and inoculated onto different agar plates (MacConkey, SS agar, MSA and nutrient agar) for cultivation of bacterial species. Colonies of E.coli, Staphylococcus spp. Brachyspira spp. and Campylobacter spp were observed based on colony morphology. Colony forming unit showed E. coli as frequently found bacteria in fecal, oral and gut contents of all the above pheasants. The overall significance difference was found among bacterial species of golden pheasants, green pheasant, ring-necked pheasant, and silver pheasants. It was concluded that E.coli is predominant isolated from heathy pheasants followed by Campylobacter, Staphylococcus and Brachyspira.
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Affiliation(s)
- M Mushtaq
- University of Veterinary and Animal Sciences, Faculty of Fisheries & Wildlife, Department of Wildlife & Ecology, Lahore, Pakistan
| | - S M Bukhari
- University of Veterinary and Animal Sciences, Faculty of Fisheries & Wildlife, Department of Wildlife & Ecology, Lahore, Pakistan
| | - S Ahmad
- University of the Punjab, Department of Entomology, Lahore, Pakistan
| | - A Khattak
- Shaheed Benazir Bhutto Women University, Department of Bioinformatics, Peshawar, Pakistan
| | - M B Chattha
- University of the Punjab, Faculty of Agricultural Sciences, Department of Agronomy, Lahore, Pakistan
| | - I Mubeen
- Government College University, Department of Zoology, Lahore, Pakistan
| | - K Ur Rehman
- GC Women University, Department of Environmental Sciences, Sialkot, Pakistan
| | - S Andleeb
- GC Women University, Department of Environmental Sciences, Sialkot, Pakistan
| | - S Hussain
- Northeast Forestry University, College of Wildlife and Protected Area, Harbin, China
| | - A Javid
- University of Veterinary and Animal Sciences, Faculty of Fisheries & Wildlife, Department of Wildlife & Ecology, Lahore, Pakistan
| | - A Hussain
- University of Veterinary and Animal Sciences, Faculty of Fisheries & Wildlife, Department of Wildlife & Ecology, Lahore, Pakistan
| | - W Ali
- University of Veterinary and Animal Sciences, Faculty of Fisheries & Wildlife, Department of Wildlife & Ecology, Lahore, Pakistan
| | - N Khalid
- University of Veterinary and Animal Sciences, Faculty of Fisheries & Wildlife, Department of Wildlife & Ecology, Lahore, Pakistan
| | - G Mustafa
- University of Veterinary and Animal Sciences, Faculty of Fisheries & Wildlife, Department of Wildlife & Ecology, Lahore, Pakistan
| | - F Sughra
- University of Education, Department of Zoology, Division of Science and Technology, Lahore, Pakistan
| | - M J Iqbal
- Bahauddin Zakariya University, Institute of Pure and Applied Biology (Zoology Division), Multan, Pakistan
| | - M Khalid
- Emerson University Multan, Department of Zoology, Punjab, Pakistan
| | - M M Naeem
- Institute of Engineering and Fertilizer Research, Department of Civil Engineering NFC, Faisalabad, Pakistan
| | - M Inayat
- University of Veterinary and Animal Sciences, Department of Fisheries and Aquaculture, Lahore, Pakistan
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Shi QH, Shabbir T, Mushtaq M, Khan MI, Shah Z, Kumam P. Modelling and numerical computation for flow of micropolar fluid towards an exponential curved surface: a Keller box method. Sci Rep 2021; 11:16351. [PMID: 34381137 PMCID: PMC8358016 DOI: 10.1038/s41598-021-95859-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2021] [Accepted: 07/15/2021] [Indexed: 11/20/2022] Open
Abstract
The numerical analysis of MHD boundary layer non-Newtonian micropolar fluid due to an exponentially curved stretching sheet is developed in this study. In the energy equation effects of viscous dissipation are included. For the mathematical description of the governing equations curvilinear coordinates are used. By utilizing exponential similarity variables, the modelled partial differential equations (PDEs) are reduced into ordinary ones. The resultant non-linear ODEs are numerically solved with two methods shooting and Keller box method. The study reveals that the governing parameters, namely, radius of curvature, material parameter, magnetic parameter, Prandtl number and Eckert number have major effects on the fluid velocity, micro-rotation velocity, surface friction, couple stress and heat transfer rate. The results indicate that the magnetic field diminishes the fluid velocity inside the hydrodynamics boundary layer whereas it enhances the temperature inside the thermal boundary layer. Microrotation profile decreases near the surface, as the magnetic parameter and radius of curvature increases but far away behavior is opposite. The material parameter enhances the velocity and microrotation profile whereas, opposite behaviors is noticed for the temperature distribution. Obtained outcomes are also compared with the existing literature and the comparison shows a good agreement with existing studies.
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Affiliation(s)
- Qiu-Hong Shi
- Department of Mathematics, Huzhou University, Huzhou, 313000, People's Republic of China
| | - Tayyaba Shabbir
- Department of Mathematics, COMSATS University Islamabad, Park Road, Chak Shahzad, Islamabad, 44000, Pakistan
| | - M Mushtaq
- Department of Mathematics, COMSATS University Islamabad, Park Road, Chak Shahzad, Islamabad, 44000, Pakistan
| | - M Ijaz Khan
- Department of Mathematics and Statistics, Riphah International University I-14, Islamabad, 44000, Pakistan
| | - Zahir Shah
- Department of Mathematical Sciences, University of Lakki Marwat, Lakki Marwat, 28420, Khyber Pakhtunkhwa, Pakistan. .,Center of Excellence in Theoretical and Computational Science (TaCS‑CoE), Faculty of Science, King Mongkut's University of Technology Thonburi (KMUTT), 126 Pracha Uthit Rd., Bang Mod, Thung Khru, Bangkok, 10140, Thailand.
| | - Poom Kumam
- Fixed Point Research Laboratory, Fixed Point Theory and Applications Research Group, Center of Excellence in Theoretical and Computational Science (TaCS‑CoE), Faculty of Science, King Mongkut's University of Technology Thonburi (KMUTT), 126 Pracha Uthit Rd., Bang Mod Thung Khru, Bangkok, 10140, Thailand. .,Department of Medical Research, China Medical University Hospital, China Medical University, Taichung, 40402, Taiwan.
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Sultana U, Mushtaq M, Khan I. Carbon Nanotubes Flow Induced by Rotating Stretching Disk with Non-Linear Radiations and Slip. Comb Chem High Throughput Screen 2021; 25:2498-2508. [PMID: 34254907 DOI: 10.2174/1386207324666210709095532] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Revised: 05/21/2021] [Accepted: 06/03/2021] [Indexed: 11/22/2022]
Abstract
BACKGROUND The phenomena of rotating disks involving flows serve as a crucial element in the field of fluid mechanics. Due to its massive practical importance in engineering and industry, considerable attention is being paid to the extensions of the problems associated with rotating stretching disks. In this regard, Carbon nanotubes (CNT) are chosen as the best example of true nanotechnology. CNTs have an incredible range of applications due to their extraordinary characteristics. But single rotating-stretching disk with CNTs fluid flow has not been plowed yet. OBJECTIVE The objective of this work is to outstretch the study of a viscous fluid with carbon nanotubes (CNTs) and transfer of heat due to radially stretching and rotating disk contingent to Navier slip, nonlinear radiations, and convective boundary conditions. METHOD Cylindrical coordinates are utilized in the modeling and the mathematical formulation of the flow equations. These flow equations take the form of ordinary differential equations by means of similarity transformations. The emanated equations are solved by two numerical methods, i.e., the shooting method and the Keller box method, respectively. Xue model of carbon nanotubes is incorporated to carry out the research. RESULTS The acquired solutions are tabulated, and precise values of the physical parameters with excellent matching results are shown. These results are juxtaposed with CNTs of multi-wall and single-wall carbon nanotubes, while water is taken as a base fluid. CONCLUSION Results reveal a significant depletion in skin friction with an increase in the slip parameter. Slip, nonlinear radiation, and Biot number proved as liable factors in escalating the rate of heat transfer.
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Affiliation(s)
- Uzma Sultana
- Department of Mathematics, COMSATS University Islamabad, Islamabad 44000, Pakistan
| | - M Mushtaq
- Department of Mathematics, COMSATS University Islamabad, Islamabad 44000, Pakistan
| | - Ilyas Khan
- Department of Mathematics, College of Science Al-Zulfi, Majmaah University, Al-Majmaah 11952, Saudi Arabia
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Shabbir T, Mushtaq M, Ijaz Khan M, Hayat T. Modeling and numerical simulation of micropolar fluid over a curved surface: Keller box method. Comput Methods Programs Biomed 2020; 187:105220. [PMID: 31790945 DOI: 10.1016/j.cmpb.2019.105220] [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] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Revised: 11/13/2019] [Accepted: 11/15/2019] [Indexed: 06/10/2023]
Abstract
BACKGROUND This paper examines the flow behavior of micropolar liquid over a curved surface. MHD fluid is considered. The surface inducing the fluid motion has a prescribed temperature different from the ambient fluid moreover the heat transfer mechanism is investigated. Curvilinear coordinates are used for the mathematical formulation of the flow equation. Similarity variables are derived and are utilized to alter the governing expressions for the flow of momentum and heat transfer characteristic. METHOD The resulting non-linear ODEs are resolved systematically by two numerically approaches namely; the Keller box method and the shooting method. RESULTS The numerical results for the temperature and velocity fields has been presented through tables and graphs against the independent parameters and non-dimensional numbers i.e., material parameter, power law index, radius of curvature, magnetic parameter, Prandtl and Eckert numbers, skin friction (drag force) and Nusselt number. Physical explanation of the graph presented is given to understand the performance of fluid flow and heat transport phenomena in different emerging situation. CONCLUSION The main outcomes in the presence of various flow variables on the skin friction velocity, Nusselt number, temperature are highlighted via graphical sketch and Tables. Velocity field displays a decreasing trend with magnetic parameter, power law index and radius of curvature of the stretching velocity whereas, opposite behavior observed for the material parameter. Near the surface curvature and magnetic parameter shows an enhancement in microrotation profile whereas, it shows reverse behavior when it is far away. Material parameter increases for large values of microrotation profile on the other hand power-law index decreases for large values. For higher values magnetic parameter, radius of curvature and Eckert number temperature profile increases. But temperature reduces subject to material parameter and Prandtl number.
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Affiliation(s)
- Tayyaba Shabbir
- Department of Mathematics, COMSATS University Islamabad, Park Road, Chak Shahzad, Islamabad 44000, Pakistan.
| | - M Mushtaq
- Department of Mathematics, COMSATS University Islamabad, Park Road, Chak Shahzad, Islamabad 44000, Pakistan
| | - M Ijaz Khan
- Department of Mathematics, COMSATS University Islamabad, Park Road, Chak Shahzad, Islamabad 44000, Pakistan.
| | - T Hayat
- Department of Mathematics, Quaid-I-Azam University 45320, Islamabad 44000, Pakistan
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Kashuba E, Mushtaq M. Do MRPS18-2 and RB proteins cooperate to control cell stemness and differentiation, preventing cancer development? Exp Oncol 2017; 39:12-16. [PMID: 28361860] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
In childhood tumors, including retinoblastoma, osteosarcoma, and neuroblastoma, the RB-E2F1 pathway is inactivated, as a rule. These tumors arise from precursor cells that fail to undergo the terminal differentiation. Noteworthy, the RB1-encoded protein (RB) does not control the cell cycle in embryonic stem cells. It has not been yet well understood how RB controls cell stemness and differentiation. The question arises why "inactive" RB is required for the survival and stemness of cells? Recently, we have found that overexpression of the RB-binding protein MRPS18-2 (S18-2) in primary fibroblasts leads to their immortalization, which is accompanied by the induction of embryonic stem cell markers and, eventually, malignant transformation. We suggest that cell stemness may be associated with high expression levels of both proteins, RB and S18-2. There must be a strict regulation of the expression levels of S18-2 and RB during embryogenesis. Disturbances in the expression of these proteins would lead to the abnormalities in development. We think that the S18-2 protein, together with the RB, plays a crucial role in the control on cell stemness and differentiation. We hope to uncover the new mechanisms of the cell fate determination. The S18-2 may serve as a new target for anticancer medicines, which will help to improve human health.
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Affiliation(s)
- E Kashuba
- R.E. Kavetsky Institute of Experimental Pathology, Oncology and Radiobiology, NAS of Ukraine, Kyiv 03022, Ukraine
| | - M Mushtaq
- Department of Microbiology, Tumor and Cell Biology (MTC), Karolinska Institutet, Stockholm S-17177, Sweden
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Malik R, Khan M, Mushtaq M. Corrigendum to "Cattaneo-Christov heat flux model for the Sisko fluid flow past a permeable non-linearly stretching cylinder" [J. Mol. Liq. 222 (2016) 430-434]. J Mol Liq 2016. [DOI: 10.1016/j.molliq.2016.09.076] [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: 11/29/2022]
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Sagir M, Mushtaq M, Tan IM, Suleman Tahir M, Pervaiz M. A novel hybrid catalyst for the esterification of high FFA in Jatropha oil for biodiesel production. Grasas y Aceites 2016. [DOI: 10.3989/gya.0216161] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Abstract
Human retinoblastoma gene RB1 is the first tumor suppressor gene (TSG) isolated by positional cloning in 1986. RB is extensively studied for its ability to regulate cell cycle by binding to E2F1 and inhibiting the transcriptional activity of the latter. In human embryonic stem cells (ESCs), only a minute trace of RB is found in complex with E2F1. Increased activity of RB triggers differentiation, cell cycle arrest, and cell death. On the other hand, inactivation of the entire RB family (RB1, RBL1, and RBL2) in human ESC induces G2/M arrest and cell death. These observations indicate that both loss and overactivity of RB could be lethal for the stemness of cells. A question arises why inactive RB is required for the survival and stemness of cells? To shed some light on this question, we analyzed the RB-binding proteins. In this review we have focused on 27 RB-binding partners that may have potential roles in different aspects of stem cell biology.
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Affiliation(s)
- M Mushtaq
- Karolinska Institutet, Stockholm, Sweden
| | | | - E V Kashuba
- Karolinska Institutet, Stockholm, Sweden; R.E. Kavetsky Institute of Experimental Pathology, Oncology and Radiobiology, NASU, Kyiv, Ukraine.
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Hasan M, Khan M, Mushtaq M, Iqbal Z, Farooq A, Sajid M, Waheed H. Prevalence of Warble Fly Infestation in Buffalo in Chakwal, Punjab. Italian Journal of Animal Science 2016. [DOI: 10.4081/ijas.2007.s2.942] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Khanum S, ur-Nisa M, Mushtaq M, Sarwar M, ul-Hassan M. PosterInfluence of Replacement of Concentrate with Enzose (Corn Dextrose)and Corn Steep Liquor on Nutrient intake inNili RaviBuffalo Bulls. Italian Journal of Animal Science 2016. [DOI: 10.4081/ijas.2007.s2.567] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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A S, Rahim S, Bhatti KH, Khan A, Din N, Imran M, Mohsin M, Ishtiaq M, Nabila A, Ansari A, Hussain S, Zafar M, Mushtaq M, Mumtaz E, Iqbal J. Ethnobotanical study and conservation status of trees in the district Sargodha, Punjab, Pakistan. ACTA ACUST UNITED AC 2015. [DOI: 10.32604/phyton.2015.84.034] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Pervaiz M, Yousaf M, Sagir M, Mushtaq M, Naz MY, Ullah S, Mushtaq R. Synthesis and Characterization of Bimetallic Post Transition Complexes for Antimicrobial Activity. ACTA ACUST UNITED AC 2014. [DOI: 10.1080/15533174.2013.841218] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Affiliation(s)
- M. Pervaiz
- Department of Chemistry, Government College University, Faisalabad, Pakistan
| | - M. Yousaf
- Department of Chemistry, Government College University, Faisalabad, Pakistan
| | - M. Sagir
- Department of Chemical Engineering, Universiti Teknologi PETRONAS, Bandar Seri Iskandar, Tronoh, Perak, Malaysia
| | - M. Mushtaq
- Department of Chemical Engineering, Universiti Teknologi PETRONAS, Bandar Seri Iskandar, Tronoh, Perak, Malaysia
| | - M. Y. Naz
- Department of Physics, University of Agriculture, Faisalabad, Pakistan
| | - S. Ullah
- Department of Chemical Engineering, Universiti Teknologi PETRONAS, Bandar Seri Iskandar, Tronoh, Perak, Malaysia
| | - R. Mushtaq
- Royal Medical College, Ipoh, Perak, Malaysia
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Mushtaq M, Ahmad MUD, Nisar M. Study on pathogenesis and genetic characterization of HPAI H5N1 isolated from a tiger in China. Int J Infect Dis 2014. [DOI: 10.1016/j.ijid.2014.03.974] [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: 10/25/2022] Open
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Maqbool A, Mushtaq M, Ahmad MUD, Nisar M. Study of socio-demographic risk factors of dengue fever in a tertiary care hospital in Pakistan. Int J Infect Dis 2014. [DOI: 10.1016/j.ijid.2014.03.956] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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Pervaiz M, Yousaf M, Sagir M, Naz M, Mushtaq M, Ullah S, Chatha S. Novel preparation and spectral investigation of monometallic transition metal Schiff base complexes (Zn, Cu, Mn, Co) as bacteria and fungus inhibitors. Main Group Chemistry 2014. [DOI: 10.3233/mgc-140128] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Affiliation(s)
- M. Pervaiz
- Department of Chemistry, Government College University, Faisalabad, Pakistan
| | - M. Yousaf
- Department of Chemistry, Government College University, Faisalabad, Pakistan
| | - M. Sagir
- Department of Chemical Engineering, Universiti Teknologi PETRONAS, Bandar Seri Iskandar, Tronoh, Perak, Malaysia
| | - M.Y. Naz
- Department of Fundamental and Applied Sciences, Universiti Teknologi PETRONAS, Bandar Seri Iskandar, Tronoh, Perak, Malaysia
- Department of Physics, University of Agriculture, Faisalabad, Pakistan
| | - M. Mushtaq
- Department of Chemical Engineering, Universiti Teknologi PETRONAS, Bandar Seri Iskandar, Tronoh, Perak, Malaysia
| | - S. Ullah
- Department of Chemical Engineering, Universiti Teknologi PETRONAS, Bandar Seri Iskandar, Tronoh, Perak, Malaysia
| | - S.A.S. Chatha
- Department of Chemistry, Government College University, Faisalabad, Pakistan
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Khan B, Aminy Raouf H, Mushtaq M. P220 Evolving role of the respiratory specialist: Pleural ultrasound service 4 years on. Thorax 2013. [DOI: 10.1136/thoraxjnl-2013-204457.372] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Ellahi R, Riaz A, Nadeem S, Mushtaq M. Series Solutions of Magnetohydrodynamic Peristaltic Flow of a Jeffrey Fluid in Eccentric Cylinders. ACTA ACUST UNITED AC 2013. [DOI: 10.12785/amis/070424] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Mushtaq M, Tan IM, Nadeem M, Devi C, Lee SYC, Sagir M, Rashid U. Epoxidation of methyl esters derived from Jatropha oil: An optimization study. Grasas y Aceites 2013. [DOI: 10.3989/gya.084612] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Iqbal MJ, Cecil F, Ahmad K, Iqbal M, Mushtaq M, Naeem M, Bokhari T. Kinetic Study of Cr(III) and Cr(VI) Biosorption Using Rosa damascena Phytomass: A Rose Waste Biomass. ACTA ACUST UNITED AC 2013. [DOI: 10.14233/ajchem.2013.13345] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Simpson TRG, Constantinescu G, Mellor P, Lohani S, Khan B, Mushtaq M, Abdelhadi I, Bhattacharjee B, Serafimov V. P196 Percutaneous Ultrasound-Guided Biopsy of Intrathoracic Parietal Masses – a Safe Alternative to CT-Guided Biopsy? Thorax 2012. [DOI: 10.1136/thoraxjnl-2012-202678.257] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Ahmad MUD, Ayesha A, Ahmad Anjum A, Ayaz M, Mushtaq M. Detection of hazardous organisms in raw and pasteurized milk with particular reference to Enterobacteriaceae. Int J Infect Dis 2012. [DOI: 10.1016/j.ijid.2012.05.403] [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: 11/29/2022] Open
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Khan B, Raouf A, Mushtaq M. 49 Qualitative and quantitative experience of Medical Thoracoscopy (MT) in a DGH. Lung Cancer 2012. [DOI: 10.1016/s0169-5002(12)70050-8] [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: 11/25/2022]
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Gross M, Amato R, Mushtaq M, Wilding G, Bubley G. 362 POSTER A phase 2 trial of AP23573, an mTOR inhibitor, in patients (pts) with taxane-resistant androgen-independent prostate cancer (AIPC). EJC Suppl 2006. [DOI: 10.1016/s1359-6349(06)70367-6] [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: 11/25/2022] Open
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Aftab M, Belaguli N, Mushtaq M, Berger D. Transforming growth factor beta1 (TGFB1) differentially regulates protease production and cellular invasion in human colon cancer. J Surg Res 2006. [DOI: 10.1016/j.jss.2005.11.023] [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: 11/29/2022]
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Talente GM, Staton LJ, Carroll MR, Mushtaq M, Larsen L. 227 ACGME DUTY HOUR REQUIREMENTS: WHAT DO FACULTY THINK? J Investig Med 2005. [DOI: 10.2310/6650.2005.00006.226] [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: 11/18/2022]
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Khokhar N, Mushtaq M, Mukhtar AS, Ilahi F. Steatosis and chronic hepatitis C virus infection. J PAK MED ASSOC 2004; 54:110-2. [PMID: 15129866] [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: 04/29/2023]
Abstract
OBJECTIVE To asses the presence of steatosis and other histological changes in patients with chronic hepatitis C. METHODS Liver biopsy samples were reviewed for presence of steatosis, its degree and other histological changes of hepatitis C including necro-inflammatory score, fibrosis grade and these changes were correlated with liver function tests. RESULTS A total of 109 liver biopsy samples were reviewed. Mean age of the patients was 44.46 +/- 13.93 years and 62 (56.8%) were male. Mean necro-inflammatory score was 2.32 +/- 0.95. Mean fibrosis grade was 1.69 +/- 1.12. No Steatosis was found in 42 (38.5%) samples and mild to severe degree of steatosis was found in 67 (61.5%) samples. CONCLUSION In this study, nearly 62% of liver biopsy samples had some degree of steatosis. Whether this steatosis increases occurrence of severe form of fibrosis or is an associated phenomena with chronic inflammation needs to be further clarified.
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Affiliation(s)
- N Khokhar
- Division of Gastroenterology, Department of Medicine, Shifa International Hospital and Shifa College of Medicine, Islamabad
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Ramirez JA, Vargas S, Ritter GW, Brier ME, Wright A, Smith S, Newman D, Burke J, Mushtaq M, Huang A. Early switch from intravenous to oral antibiotics and early hospital discharge: a prospective observational study of 200 consecutive patients with community-acquired pneumonia. Arch Intern Med 1999; 159:2449-54. [PMID: 10665893 DOI: 10.1001/archinte.159.20.2449] [Citation(s) in RCA: 156] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
UNLABELLED To determine the proportion of patients who can be treated with early switch to oral antibiotics and early discharge, to evaluate clinical outcome and patient satisfaction for patients treated with early switch and early discharge, and to define the factors that interfere with early discharge for some of the patients who underwent early switch to oral antibiotic therapy. DESIGN Prospective study. PARTICIPANTS Two hundred consecutive hospitalized patients with community-acquired pneumonia. MAIN OUTCOME MEASURES Number of days needed to switch to oral therapy and length of hospital stay. Clinical outcome and satisfaction with care were evaluated for those patients treated with early switch and early discharge. RESULTS Early switch to oral antibiotics (within the first 3 days of hospitalization) was performed in 133 patients (67%). Clinical failure was documented in 1 patient. Early switch and early discharge was performed in 88 patients (44%). The mean length of hospital stay for this group was 3.4 days. The most common reason for prolonged hospitalization after the switch to oral antibiotics was the need for diagnostic workup. More than 95% of patients were satisfied with the care they had received. CONCLUSIONS Using simple clinical and laboratory criteria, a significant proportion of hospitalized patients with community-acquired pneumonia (44%) can be treated with early switch and early discharge. This model did not affect patient outcome, decreased the length of hospitalization, and was associated with a high level of patient satisfaction.
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Affiliation(s)
- J A Ramirez
- Department of Medicine, University of Louisville School of Medicine and Veterans Affairs Medical Center, KY 40202, USA
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30
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Abstract
In 1991 the West Midlands Pulmonary Function Audit Group examined the consistency between pulmonary function laboratories in the West Midlands. Three healthy subjects visited 22 centres and performed a standard set of pulmonary function tests. Demographic data on nine hypothetical subjects was also supplied for the laboratories to produce predicted values. Equipment was checked for accuracy using standard methods. The 1991 audit revealed significant inter-laboratory variability. Sources of error were identified and after consultation, recommendations were made to improve consistency. In addition, national and regional training workshops were organized for laboratory staff. In 1995 the audit was repeated using the same three subjects. Significant differences continued for all predicted results except for residual volume (RV) and forced vital capacity (FVC) and for all measured results except for functional residual capacity (FRC). However, improvements in the coefficient of variation were seen compared with 1991 for predicted forced expiratory volume (FEV1), total lung capacity (TLC), gas transfer (TLCO), FVC, FRC and RV. Similar improvements were seen in measured results for FEV1 and FVC. Increased variation was seen for predicted corrected transfer factor (KCO) and actual RV. The majority of variables in the 1995 audit had a coefficient of variation of less than 5% between laboratories. Analysis of the predicted results from the hypothetical subjects continued to show unacceptable variation reflecting continuing computer algorithm inconsistency. The improvements seen are encouraging and suggest that a regular audit programme is worthwhile.
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Affiliation(s)
- L J Dowson
- West Midlands Respiratory Function Audit Group, Royal Shrewsbury Hospital, U.K
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Wrzesinski CL, Mushtaq M, Faidley T, Johnson N, Arison B, Crouch LS. Metabolism of 3H/14C-labeled 4''-deoxy-4''-epimethylaminoavermectin B1a benzoate in chickens. Identification of novel fatty acid conjugates of '4'-deoxy-4''-epimethylaminoavermectin B1a. Drug Metab Dispos 1998; 26:786-94. [PMID: 9698294] [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: 02/08/2023] Open
Abstract
The metabolism of 3H/14C-labeled 4"-deoxy-4"-epimethylaminoavermectin B1a (MAB1a) benzoate, the major homologue (>/=90%) of the avermectin insecticide emamectin benzoate, was studied in laying chickens. Ten Leghorn hens (Gallus domesticus) were orally dosed once daily for 7 days (1 mg/kg of body weight/day). Eggs and excreta were collected daily, and eggs were subsequently separated into whites and yolks. Chickens were euthanized within 20 hr after the last dose, and liver, kidney, heart, muscle, fat, ovaries, gizzard, gastrointestinal tract and contents, and carcass were collected. Approximately 70 and 6% of the total administered dose were recovered in the excreta plus gastrointestinal tract and contents and in the tissues plus eggs, respectively. Two novel metabolites, i.e. the 24-hydroxymethyl derivative of the parent compound (24-hydroxymethyl-4"-deoxy-4"-epimethylaminoavermectin B1a) and the N-demethylated derivative of 24-hydroxymethyl-4"-deoxy-4"-epimethylaminoavermectin B1a (24-hydroxymethyl-4"-deoxy-4"-epiaminoavermectin B1a), were identified. In addition, eight fatty acid conjugates of each of these two metabolites, comprising 8-75% of total radioactive residues in tissues and eggs, were isolated and identified. Although this represents some of the most extensive in vivo fatty acid conjugation to a xenobiotic reported to date, potential human exposure to MAB1a residues from consumption of chicken would be extremely low, because the dosage level in this study was approximately 1000-fold greater than the MAB1a residue levels seen in crops and because the majority of the applied dose was recovered in the excreta. Based on these findings, the avian biotransformation of MAB1a differs substantially from the mammalian biotransformation.
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Affiliation(s)
- C L Wrzesinski
- Pesticide Metabolism and Environmental Safety Group, Merck Research Laboratories, USA
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Mushtaq M, Kulp S, Chang W, Lin YC. Gossypol inhibits human chorionic gonadotropin-stimulated testosterone production by cultured canine testicular interstitial cells. Res Commun Mol Pathol Pharmacol 1996; 91:259-72. [PMID: 8829766] [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] [Grants] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Gossypol (GP) is a natural polyphenolic compound that possesses antifertility and antisteroidogenic activities in both males and females. The dog is highly sensitive to GP toxicity, yet GP's effect on canine testicular steroidogenesis has never been reported. Thus, the present study examines GP's effects on human chorionic gonadotropin (hCG)-induced testosterone (T) production by primary cultured canine testicular interstitial cells. After decapsulation and enzymatic dissociation of canine testes in Dulbecco's Modified Eagle Medium with Ham's Nutrient Mixture F-12 (1:1; DME/F-12) containing 0.1% collagenase, 0.1% BSA, and 10 micrograms/ml DNase 1 (37 degrees C, 20 min), interstitial cells were isolated by sedimentation and filtration (140 microns) and then cultured in supplemented DME/F-12 medium (5 micrograms/ml insulin, 5 micrograms/ml transferrin, 5 ng/ml sodium selenite; DME/F-12/S) containing 0.1% fetal bovine serum (FBS). FBS was used to enhance cell attachment during the first 24 hours of culture. After 24 hours, the medium was replaced with serum-free DME/F-12/S and the cells were cultured for an additional 24 hours. Thereafter, cells were treated with hCG (0.1 IU/ml) alone and in combination with GP (0.05, 0.5, 2.5 and 5.0 microM). Media were collected for T radioimmunoassay and cells for protein estimation after 8, 16 and 24 hours of treatment. Treatment with hCG significantly (p < 0.05) stimulated T production over that of controls at all treatment times examined. At 8, 16 and 24 hours, T secretion was elevated from 0.91 +/- 0.25, 1.32 +/- 0.42, and 1.41 +/- 0.40 pg/microgram protein to 2.36 +/- 0.50, 2.84 +/- 0.60, and 2.82 +/- 0.43 pg/microgram protein, respectively. At 0.5, 2.5 and 5.0 microM, GP significantly (p < 0.05) reduced hCG-induced T secretion at 16 and 24 hours of treatment to 1.79 +/- 0.50, 1.62 +/- 0.12, 1.34 +/- 0.16 (16 hr), and 1.53 +/- 0.38, 1.43 +/- 0.11, 1.42 +/- 0.32 (24 hr) pg/microgram protein, respectively. At 8 hours, T production was reduced by 2.5 and 5.0 microM GP to 1.08 +/- 0.55 and 0.93 +/- 0.61 pg/microgram protein, respectively. GP, however, did not reduce T production to below basal levels. These results demonstrate the inhibition of hCG-induced T production by GP in cultured canine testicular interstitial cells.
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Affiliation(s)
- M Mushtaq
- Department of Veterinary Physiology and Pharmacology, College of Veterinary Medicine, Ohio State University, Columbus 43210-1092, USA
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Abstract
BACKGROUND Pulmonary function testing has become an integral part of the assessment and follow-up of patients with pulmonary disease. Many factors can influence the results produced by a laboratory. This audit was performed to examine the extent of variation in the pulmonary function test results amongst all laboratories in the West Midlands. This was followed by an attempt to determine the cause of this variation. METHODS Phase 1. Three normal healthy subjects each underwent a set of pulmonary function tests in all 22 laboratories in the West Midlands. Information regarding technicians' qualifications, training and seniority, protocol and equipment used were obtained in the form of a questionnaire. Phase 2. All 22 laboratories were asked to calculate the predicted values on the same nine sets of demographic data. These data included both sexes, ethnic minorities and range of ages. In addition technical aspects of each laboratory were investigated including the assessment of volume and gas analysers with standard gases containing known concentrations of helium and carbon monoxide. RESULTS Phase 1. Significant variations (P < 0.05) were observed in all measured values of pulmonary function tests of the three subjects. Significant variations (P < 0.05) were also observed in all predicted values except total lung capacity. Phase 2. There were significant variations (P < 0.05) amongst laboratories in calculating the predicted values of all components of pulmonary function tests. No significant differences were observed in the measurement of volume or concentration of carbon monoxide or helium.
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Affiliation(s)
- M Mushtaq
- Department of Respiratory Medicine, Princess Royal Hospital, Telford, U.K
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Abstract
A patient with multiple cystic hamartomas presented with a pneumothorax and later developed a cystic myxomatous vaginal polyp. This and three of the cysts were resected. She remains well 13 years later. Multiple cystic hamartomas are uncommon and may be misdiagnosed as pulmonary metastases.
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Affiliation(s)
- M Mushtaq
- Department of Respiratory Medicine, New Cross and Royal Hospitals, Wolverhampton
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Abstract
1,12-Dimethylbenz[a]anthracene (1,12-DMBA) cis-5,6-dihydrodiol was synthesized by oxidation of 1,12-DMBA with osmium tetroxide in pyridine in low yield (less than or equal to 3%) and was purified by sequential use of reversed-phase and normal-phase HPLC. Two pairs of 1,12-DMBA cis-5,6-dihydrodiol enantiomers, derived from P (right-handed helix) and M (left-handed helix) conformers, were eluted as a single chromatographic peak on both reversed-phase and normal-phase HPLC. However, these four enantiomers were resolved by sequential use of two chiral stationary phase (CSP) HPLC columns. CSP (Pirkle type I) columns were packed with either (R)-N-(3,5-dinitrobenzoyl)phenylglycine or (S)-N-(3,5-dinitrobenzoyl)leucine, which is ionically bonded to gamma-aminopropylsilanized silica. Absolute configurations of enantiomers were determined by comparing their circular dichroism spectra with those of conformationally similar cis-5,6-dihydrodiol enantiomers of 4-methylbenz[a]anthracene and 7,12-dimethylbenz[a]anthracene with known absolute stereochemistry.
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Affiliation(s)
- S K Yang
- Department of Pharmacology, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, Maryland 20814-4799
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Mushtaq M, Weems HB, Yang SK. Stereoselective formations of enantiomeric K-region epoxide and trans-dihydrodiols in dibenz[a,h]anthracene metabolism. Chem Res Toxicol 1989; 2:84-93. [PMID: 2519714 DOI: 10.1021/tx00008a003] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Metabolism of dibenz[a,h]anthracene (DBA) to optically active epoxide and dihydrodiol products by rat liver microsomes was investigated. Enantiomeric separation of K-region 5,6-epoxide, trans- and cis-5,6-dihydrodiols, non-K-region trans-1,2- and trans-3, 4-dihydrodiols, and O-methyl ethers derived from methoxylation of racemic and enantiomeric K-region 5,6-epoxides was performed on HPLC columns packed with Pirkle chiral stationary-phase (CSP) (R)-N-(3,5-dinitrobenzoyl)phenylglycine (R-DNBPG) or (S)-N-(3,5-dinitrobenzoyl) leucine (S-DNBL), which was either ionically or covalently bonded to a silica gel support. Enantiomers of DBA 5,6-epoxide, trans-5,6-dihydrodiol, and its two isomeric O-methyl ethers were efficiently separated on the ionically bonded R-DNBPG column. Enantiomers of DBA cis-5, 6-dihydrodiol were resolved on both ionically and covalently bonded S-DNBL columns. Enantiomeric pairs of the non-K-region trans-1,2- and 3,4-dihydrodiols were poorly resolved on all CSPs tested. DBA was incubated with a NADPH-regenerating system and liver microsomes from untreated, phenobarbital- (PB) treated, 3-methylcholanthrene- (MC) treated, and polychlorinated biphenyl (PCB, Aroclor 1254) treated rats either in the absence or in the presence of an epoxide hydrolase inhibitor, 3,3,3-trichloropropylene 1,2-oxide (TCPO). Metabolites formed were analyzed by reversed-phase, normal-phase, and CSP HPLC. CD spectral and CSP-HPLC analyses of metabolically formed trans-dihydrodiols indicated that the dihydrodiols are highly enriched in the R,R-enantiomers.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- M Mushtaq
- Department of Pharmacology, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, Maryland 20814-4799
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Yang SK, Mushtaq M, Bao ZP, Weems HB, Shou MG, Lu XL. Improved enantiomeric separation of dihydrodiols of polycyclic aromatic hydrocarbons on chiral stationary phases by derivatization to O-methyl ethers. J Chromatogr A 1989; 461:377-95. [PMID: 2708480 DOI: 10.1016/s0021-9673(00)94305-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
K-region trans-dihydrodiol derivatives of phenanthrene, 1-methylphenanthrene, 4,5-methylenephenanthrene, pyrene, 1-bromopyrene, chrysene, benzo[c]phenanthrene, benz[a]anthracene, 1-, 4-, 6-, 7-, 11- and 12-methylbenz[a]anthracenes, 7,12-dimethylbenz[a]anthracene, 3-methylcholanthrene, and benzo[a]pyrene, and non-K-region trans-3,4-dihydrodiols of benz[a]anthracene, chrysene, and 7,12-dimethylbenz[a]anthracene are converted to O-methyl ethers. Enantiomers of these O-methyl ethers are generally more efficiently separated on Pirkle's chiral stationary phases than the enantiomers of underivatized dihydrodiols. O-Methyl ethers are substantially less polar than dihydrodiols, and O-methyl ethers are eluted with shorter retention times. Eluents of lower polarity can hence be used. This enhances chiral interactions between chiral stationary phase and solutes, allowing improved separation of enantiomers.
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Affiliation(s)
- S K Yang
- Department of Pharmacology, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814-4799
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Weems HB, Mushtaq M, Yang SK. Absolute configurations of K-region epoxide enantiomers of 3-methylcholanthrene, benz[a]anthracene, and benzo[a]pyrene. Anal Chem 1987; 59:2679-88. [PMID: 3425917 DOI: 10.1021/ac00149a011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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Yang SK, Mushtaq M, Weems HB, Miller DW, Fu PP. Stereoselective formation and hydration of 12-methylbenz[a]anthracene 5,6-epoxide enantiomers by rat liver microsomal enzymes. Biochem J 1987; 245:191-204. [PMID: 3663145 PMCID: PMC1148099 DOI: 10.1042/bj2450191] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The K-region trans-5,6-dihydrodiols formed in the metabolism of 12-methylbenz[a]anthracene (12-MBA) by liver microsomal preparations from untreated, phenobarbital-treated and 3-methylcholanthrene-treated male Sprague-Dawley rats were found by chiral stationary-phase h.p.l.c. (c.s.p.-h.p.l.c.) analyses to contain (5S,6S)/(5R,6R) enantiomer ratios of 93:7, 88:12 and 97:3 respectively. The absolute stereochemistry of a 12-MBA trans-5,6-dihydrodiol enantiomer was elucidated by the exciton-chirality c.d. method. The 5,6-epoxides formed in the metabolism of 12-MBA by liver microsomal preparations from untreated, phenobarbital-treated and 3-methylcholanthrene-treated male Sprague-Dawley rats in the presence of the epoxide hydrolase inhibitor 3,3,3-trichloropropylene 1,2-oxide were isolated from a mixture of metabolites by normal-phase h.p.l.c., and their (5S,6R)/(5R,6S) enantiomer ratios were found by c.s.p.-h.p.l.c. analyses to be 73:27, 78:22 and 99:1 respectively. The absolute configurations of 12-MBA 5,6-epoxide enantiomers, resolved by c.s.p.-h.p.l.c., were determined via high-resolution (500 MHz) proton-n.m.r. and c.d. spectral analyses of the two isomeric methoxylation products derived from each of the 12-MBA 5,6-epoxide enantiomers. Enantiomeric pairs of the two methoxylation products were resolved by c.s.p.-h.p.l.c. The results indicate that enantiomeric 5S,6R-epoxide and 5S,6S-dihydrodiol were the major enantiomers preferentially formed in the metabolism at the K-region 5,6-double bond of 12-MBA by all three rat liver microsomal preparations. Optically pure 12-MBA 5S,6R-epoxide was hydrated predominantly at the C(6) position (R centre) to form 12-MBA trans-5,6-dihydrodiol with a (5S,6S)/(5R,6R) enantiomer ratio of 97:3. However, optically pure 12-MBA 5R,6S-epoxide was hydrated nearly equally at both C(5) and C(6) positions to form 12-MBA trans-5,6-dihydrodiol with a (5S,6S)/(5R,6R) enantiomer ratio of 57:43.
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Affiliation(s)
- S K Yang
- Department of Pharmacology, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814-4799
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Yang SK, Mushtaq M, Weems HB. Stereoselective formation and hydration of benzo[c]phenanthrene 3,4- and 5,6-epoxide enantiomers by rat liver microsomal enzymes. Arch Biochem Biophys 1987; 255:48-63. [PMID: 3592667 DOI: 10.1016/0003-9861(87)90293-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The K-region 5,6-epoxides, formed in the metabolism of benzo[c]phenanthrene (BcPh) in the presence of an epoxide hydrolase inhibitor 3,3,3-trichloropropylene 1,2-oxide (TCPO) by liver microsomes from untreated, phenobarbital-treated, 3-methylcholanthrene-treated, and polychlorinated biphenyls (Aroclor 1254)-treated rats of the Sprague-Dawley and the Long-Evans strains, were found by chiral stationary phase high-performance liquid chromatography analyses to be enriched (58-72%) in the 5S, 6R enantiomer. In the absence of TCPO, the metabolically formed BcPh trans-5,6-dihydrodiol was enriched (78-86%) in the 5S,6S enantiomer. The major enantiomer of the BcPh 3,4-epoxide metabolite was found to be enriched in the 3S,4R enantiomer which undergoes racemization under the experimental conditions. The major enantiomer of the 5,6-dihydrodiol metabolite was elucidated by the exciton chirality circular dichroism (CD) method to have a 5S,6S absolute stereochemistry. Absolute configurations of enantiomeric methoxylation products derived from each of the two BcPh 5,6-epoxide enantiomers. Optically pure BcPh 5S,6R-epoxide was enzymatically hydrated exclusively at the C6 position to form an optically pure BcPh 5S,6S-dihydrodiol. However, optically pure BcPh 5R,6S-epoxide was hydrated at both C5 and C6 positions to form a BcPh trans-5,6-dihydrodiol with a (5S,6S):(5R,6R) enantiomer ratio of 32:68.
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Abstract
The enantiomeric compositions of benzo[c]phenanthrene trans-3,4-dihydrodiol, a metabolic precursor of the ultimate carcinogenic bay-region 3,4-dihydrodiol-1,2-epoxides, formed in the metabolism of BcPh by liver microsomes from untreated, phenobarbital (PB)-treated, 3-methylcholanthrene (MC)-treated and polychlorinated biphenyls (PCB; Aroclor 1254)-treated rats of the Sprague-Dawley and Long-Evans strain were each determined by chiral stationary-phase h.p.l.c. and circular dichroism spectral analyses. The percentage of 3R,4R enantiomer in the trans-3,4-dihydrodiol metabolite of BcPh varies, depending on the concentration of liver microsomal enzymes used and the time of incubation: 29-30% (control), 46-54% (PB), 94-100% (MC) and 90-99% (PCB).
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Mushtaq M, Bao Z, Yang SK. Reversed-phase high-performance liquid chromatographic separation of phenolic derivatives of benzo[a]pyrene, benz[a]anthracene, and chrysene with monomeric and polymeric C18 columns. J Chromatogr A 1987; 385:293-8. [PMID: 3558585 DOI: 10.1016/s0021-9673(01)94643-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The separation of monohydroxylated derivatives (phenols) of benzo[a]pyrene, benz[a]anthracene, and chrysene was studied by reversed-phase high-performance liquid chromatography using a monomeric Zorbax ODS column and a polymeric Vydac C18 column. The Vydac C18 column resolved the phenols of each hydrocarbon with a wide range of retention times than the Zorbax ODS column. Four K-region phenols of benzo[a]pyrene are either not separated or marginally separated on both monomeric and polymeric columns. Other K-region and non-K-region phenols of all three hydrocarbons can be separated by using the monomeric and polymeric columns in combination.
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Weems HB, Mushtaq M, Fu PP, Yang SK. Direct separation of non-K-region mono-ol and diol enantiomers of phenanthrene, benz[a]anthracene, and chrysene by high-performance liquid chromatography with chiral stationary phases. J Chromatogr A 1986; 371:211-25. [PMID: 3558547 DOI: 10.1016/s0021-9673(01)94706-5] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The direct separation of 26 bay region and non-bay region mono-ol and diol enantiomers of phenanthrene, benz[a]anthracene, and chrysene was compared by high-performance liquid chromatography on commercially available columns, packed with gamma-aminopropylsilanized silica to which either (R)-N-(3,5-dinitrobenzoyl)phenylglycine(R-DNBPG) or (S)-N-(3,5-dinitrobenzoyl)leucine(S-DNBL) was either ionically or covalently bonded. In general, enantiomers of bay region mono-ols and diols are more efficiently resolved than those of non-bay region derivatives. Elution orders of enantiomers on either chiral stationary phase are the same, regardless of whether the chiral stationary phase is ionically or covalently bonded. Except for the enantiomers of 4-hydroxy-4-methyl-1,2,3,4-tetrahydrobenz[a]anthracene, 1,2,3,4-tetrahydrobenz[a]anthracene trans-1,2-diol, and benz[a]anthracene trans-1,2-dihydrodiol, elution orders of resolved enantiomers on R-DNBPG are reversed on S-DNBL. The enantiomers are generally more efficiently resolved on R-DNBPG than on S-DNBL. With the exception of the elution order of the enantiomeric 4-hydroxy-1,2,3,4-tetrahydrochrysene, the results of this study are consistent with the chiral recognition mechanisms proposed by Pirkle and co-workers, who developed the chiral stationary phases used in this study.
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Yang SK, Mushtaq M, Fu PP. Elution order-absolute configuration relationship of K-region dihydrodiol enantiomers of benz[a]anthracene derivatives in chiral stationary phase high-performance liquid chromatography. J Chromatogr A 1986; 371:195-209. [PMID: 3558546 DOI: 10.1016/s0021-9673(01)94705-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The direct resolution of K-region cis- and trans-dihydrodiol enantiomers of 14 unsubstituted and methyl- and bromo-substituted benz[a]anthracene (BA) derivatives was investigated by high-performance liquid chromatography with commercially available columns, packed with gamma-aminopropylsilanized silica to which either (R)-N-(3,5-dinitrobenzoyl)phenylglycine (R-DNBPG) or (S)-N-(3,5-dinitrobenzoyl)leucine (S-DNBL) is either ionically or covalently bonded. BA derivatives used in this study include: BA, 1-methyl-BA, 4-methyl-BA, 7-methyl-BA, 8-methyl-BA, 10-methyl-BA, 11-methyl-BA, 12-methyl-BA, 7,12-dimethyl-BA, 7-bromo-BA, 7-bromo-1-methyl-BA, 7-bromo-11-methyl-BA, 7-bromo-12-methyl-BA, and 3-methylcholanthrene. The enantiomers of BA trans-5,6-dihydrodiol were the only compounds not resolved by any of the four chiral stationary phases (CSPs) tested. The results indicate that conformational preference of the hydroxyl group is one of the most important factor in determining the elution order of dihydrodiol enantiomers. The presence and the location of a substituent and the molecular size and shape of the dihydrodiols can significantly affect the efficiency of enantiomeric resolution. In general, the ionically bonded R-DNBPG provides the best resolution of enantiomeric quasidiequatorial trans-dihydrodiols and the R,R enantiomers are consistently more strongly retained. In contrast, the enantiomeric pairs of quasidiaxial trans-dihydrodiols are generally better resolved by the covalently bonded R-DNBPG, and the S,S enantiomers are more strongly retained. The enantiomers of cis-dihydrodiols having hydroxyl groups that adopt quasiequatorial-quasiaxial and/or quasiaxial-quasiequatorial conformations are more consistently resolved by the ionically bonded S-DNBL and in all cases the S,R enantiomers are more strongly retained. Thus, it is possible to choose a CSP which resolves the K-region dihydrodiol enantiomers with a predictable elution order.
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Abstract
The non-K-region benz[a]anthracene (BA) 8,9- and 10,11-epoxides were isolated by normal-phase high-performance liquid chromatography as rat liver microsomal metabolites of BA. The identities of these epoxides were established by ultraviolet and mass spectral analyses and were further validated by the microsomal epoxide hydrolase catalyzed conversion to BA trans-8,9-dihydrodiol and trans-10,11-dihydrodiol, respectively. Circular dichroism spectral analyses of the metabolically formed non-K-region epoxides and dihydrodiols and mass spectral analyses of metabolically formed 18O-labeled non-K-region dihydrodiols and their acid-catalyzed dehydration products indicated that BA (8R,9S)-epoxide and (10S,11R)-epoxide were the predominant enantiomers formed in the metabolism at the 8,9- and 10,11- aromatic double bonds of BA, respectively, by rat liver microsomes. This is the first example demonstrating the direct detection and stereoselective metabolic formation of non-K-region epoxides of a polycyclic aromatic hydrocarbon.
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Yang SK, Mushtaq M, Chiu PL, Weems HB. Stereoselectivity of rat liver cytochrome P-450 isozymes: direct determination of enantiomeric composition of K-region epoxides formed in the metabolism of benz[a]anthracene and 7,12-dimethylbenz[a]anthracene. Adv Exp Med Biol 1986; 197:809-18. [PMID: 3094342 DOI: 10.1007/978-1-4684-5134-4_76] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The K-region 5,6-epoxides of benz[a]anthracene (BA) and 7,12-dimethylbenz[a]anthracene (DMBA) were isolated by normal-phase HPLC from metabolites formed by incubation of the respective parent compound with liver microsomes from untreated (control), phenobarbital (PB)-treated, and 3-methylcholanthrene (MC)-treated rats in the presence of an epoxide hydrolase inhibitor, 3,3,3-trichloropropylene 1,2-oxide. The enantiomeric contents of the metabolically formed K-region 5,6-epoxides of BA and DMBA were directly determined by chiral stationary phase HPLC. The K-region 5,6-epoxides formed in the metabolism of BA have (5R,6S): (5S,6R) enantiomer ratios of 25:75 (control), 21:79 (PB), and 4:96 (MC), respectively. In contrast, the (5R,6S):(5S,6R) enantiomeric ratios of the K-region 5,6-epoxides formed in the metabolism of DMBA are 76:24 (control), 80:20 (PB), and 97:3 (MC), respectively. These and earlier results on the stereoselective K-region metabolism studies of 7-methylbenz[a]anthracene and 12-methylbenz[a]anthracene indicate that cytochrome P-450 isozymes exhibit different stereoselectivities in the K-region epoxidations of BA and DMBA and a methyl substituent at the C12 position of BA alters the stereoheterotopic interactions between cytochrome P-450 isozymes and the BA molecule.
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Mushtaq M, Fu PP, Miller DW, Yang SK. Metabolism of 6-methylbenz[a]anthracene by rat liver microsomes and mutagenicity of metabolites. Cancer Res 1985; 45:4006-14. [PMID: 3896475] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
6-Methylbenz[a]anthracene (6-MBA) is metabolized by rat liver microsomes to form 3-hydroxy-6-MBA, 4-hydroxy-6-MBA, 5-hydroxy-6-MBA, 6-MBA trans-3,4-, 5,6-, 8,9-, and 10,11-dihydrodiols, and 4-hydroxy-6-MBA trans-10,11-dihydrodiol as the identifiable metabolites. 6-Hydroxymethylbenz[a]anthracene and its phenolic and dihydrodiol metabolites are also formed. The unique metabolites identified in 6-MBA metabolism are 6-MBA trans-5,6-dihydrodiol and 4-hydroxy-6-MBA trans-10,11-dihydrodiol. Metabolites were isolated by reversed-phase and normal-phase high-performance liquid chromatographies and identified by UV-visible absorption, mass, and proton nuclear magnetic resonance spectral analyses. Metabolites formed by low and high concentrations of liver microsomal enzymes from untreated, phenobarbital-treated, and 3-methylcholanthrene-treated male Sprague-Dawley rats were quantified by using [3H]6-MBA, with the tritium labeled at the methyl carbon, and liquid scintillation counting of fractions collected from reversed-phase high-performance liquid chromatography. Metabolic formations of 6-hydroxymethylbenz[a]anthracene, 6-MBA trans-dihydrodiols, and 4-hydroxy-6-MBA trans-10,11-dihydrodiol are highly dependent on the contents of cytochrome P-450 isozymes present in liver microsomes. The relative mutagenic activities of metabolites toward Salmonella typhimurium TA100 are: 6-MBA trans-3,4-dihydrodiol greater than 6-MBA trans-8,9-dihydrodiol greater than 6-MBA greater than 6-MBA trans-10,11-dihydrodiol greater than 4-hydroxy-6-MBA congruent to 4-hydroxy-6-MBA trans-10,11-dihydrodiol. The relatively high mutagenic activities of 6-MBA trans-3,4-dihydrodiol and 6-MBA trans-8,9-dihydrodiol suggest that both 6-MBA trans-3,4-dihydrodiol 1,2-epoxide(s) and 6-MBA trans-8,9-dihydrodiol 10,11-epoxide(s) may be the major metabolites which contribute to the carcinogenic properties of 6-MBA.
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Weems HB, Mushtaq M, Yang SK. Resolution of epoxide enantiomers of polycyclic aromatic hydrocarbons by chiral stationary-phase high-performance liquid chromatography. Anal Biochem 1985; 148:328-38. [PMID: 4061813 DOI: 10.1016/0003-2697(85)90236-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Enantiomers of nine K-region and one non-K-region epoxides of polycyclic aromatic hydrocarbons have been resolved by high-performance liquid chromatography with chiral stationary phases either ionically or covalently bonded to gamma-aminopropylsilanized silica. Resolution of enantiomers was confirmed by ultraviolet-visible absorption, circular dichroism, and mass spectral analyses. This method has been applied to the determination of optical purity and absolute configuration of the K-region epoxides formed in the metabolism of 1-methylbenz[a]anthracene, 7-methylbenz[a]anthracene, and 12-methylbenz[a]anthracene by rat liver microsomes.
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Abstract
The enantiomers of 7,12-dimethylbenz[a]anthracene (DMBA) 5,6-epoxide were directly resolved by normal-phase high-performance liquid chromatography with an ionically bonded chiral stationary phase. The absolute configurations of the resolved enantiomers were determined by comparison of circular dichroism spectra of the methanolysis products formed from the epoxide enantiomers with that of a DMBA trans-5,6-dihydrodiol enantiomer of known absolute stereochemistry. DMBA 5R,6S-epoxide is hydrated by rat liver microsomal epoxide hydrolase predominantly (95%) to a 5S,6S-dihydrodiol. The results indicate that the 5S,6S-dihydrodiol formed from the metabolism of DMBA by microsomes prepared from the livers of 3-methylcholanthrene-treated rats is predominantly derived from a 5R,6S-epoxide intermediate.
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MESH Headings
- 9,10-Dimethyl-1,2-benzanthracene/analogs & derivatives
- 9,10-Dimethyl-1,2-benzanthracene/isolation & purification
- 9,10-Dimethyl-1,2-benzanthracene/metabolism
- Animals
- Chemical Phenomena
- Chemistry
- Chromatography, High Pressure Liquid
- Circular Dichroism
- Epoxide Hydrolases/metabolism
- Male
- Microsomes, Liver/metabolism
- Rats
- Rats, Inbred Strains
- Spectrophotometry, Ultraviolet
- Stereoisomerism
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Chiu PL, Mushtaq M, Weems HB, Yang SK. Stereoselective hydroxylation at the aliphatic carbons of 7,8- and 9,10-dihydrobenzo[a]pyrenes by rat liver microsomes. Biochem Biophys Res Commun 1984; 124:114-20. [PMID: 6497875 DOI: 10.1016/0006-291x(84)90924-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Optically active 7-hydroxy-7,8-dihydrobenzo[a]pyrene and 8-hydroxy-7,8-dihydrobenzo[a]pyrene were identified as two of the major metabolites formed by incubation of 7,8-dihydrobenzo[a]pyrene with rat liver microsomes. Optically active 9-hydroxy-9,10-dihydrobenzo[a]pyrene and 10-hydroxy-9,10-dihydrobenzo[a]pyrene were similarly identified as two of the minor metabolites of 9,10-dihydrobenzo[a]pyrene. The formation of these metabolites was abolished either by prior treatment of liver microsomes with carbon monoxide or the absence of NADPH, but was not inhibited by an epoxide hydrolase inhibitor. The results indicate that the aliphatic carbons of dihydro polycyclic aromatic hydrocarbons may undergo stereoselective hydroxylation reactions catalyzed by the cytochrome P-450 system of rat liver microsomes.
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