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Ikram S, Sayyah E, Durdagi S. Identifying Potential SOS1 Inhibitors via Virtual Screening of Multiple Small Molecule Libraries against KRAS-SOS1 Interface. Chembiochem 2024:e202400008. [PMID: 38622060 DOI: 10.1002/cbic.202400008] [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: 01/03/2024] [Revised: 04/12/2024] [Accepted: 04/15/2024] [Indexed: 04/17/2024]
Abstract
The RAS-MAPK signaling pathway, crucial for cell proliferation and differentiation, involves key proteins KRAS and SOS1. Mutations in the KRAS and SOS1 genes are implicated in various cancer types, including pancreatic, lung, and juvenile myelomonocytic leukemia. There is considerable interest in identifying inhibitors targeting KRAS and SOS1 to explore potential therapeutic strategies for cancer treatment. In this study, advanced in silico techniques were employed to screen small molecule libraries at this interface, leading to the identification of promising lead compounds as potential SOS1 inhibitors. Comparative analysis of the average binding free energies of these predicted potent compounds with known SOS1 small molecule inhibitors revealed that the identified compounds display similar or even superior predicted binding affinities compared to the known inhibitors. These findings offer valuable insights into the potential of these compounds as candidates for further development as effective anti-cancer agents.
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Affiliation(s)
- Saima Ikram
- Bahcesehir University, Department of Biophysics, TURKEY
| | | | - Serdar Durdagi
- Bahcesehir University, School of Medicine, Biophysics, Besiktas, 34353, Istanbul, TURKEY
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Giner G, Ikram S, Herold MJ, Papenfuss AT. A systematic review of computational methods for designing efficient guides for CRISPR DNA base editor systems. Brief Bioinform 2023:7191601. [PMID: 37287132 DOI: 10.1093/bib/bbad205] [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] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 04/20/2023] [Accepted: 05/15/2023] [Indexed: 06/09/2023] Open
Abstract
In only a few years, as a breakthrough technology, clustered regularly interspaced short palindromic repeats/CRISPR-associated protein (CRISPR/Cas) gene-editing systems have ushered in the era of genome engineering with a plethora of applications. One of the most promising CRISPR tools, so-called base editors, opened an exciting avenue for exploring new therapeutic approaches through controlled mutagenesis. However, the efficiency of a base editor guide varies depending on several biological determinants, such as chromatin accessibility, DNA repair proteins, transcriptional activity, factors related to local sequence context and so on. Thus, the success of genetic perturbation directed by CRISPR/Cas base-editing systems relies on an optimal single guide RNA (sgRNA) design, taking those determinants into account. Although there is 11 commonly used software to design guides specifically for base editors, only three of them investigated and implemented those biological determinants into their models. This review presents the key features, capabilities and limitations of all currently available software with a particular focus on predictive model-based algorithms. Here, we summarize existing software for sgRNA design and provide a base for improving the efficiency of existing available software suites for precise target base editing.
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Affiliation(s)
- Göknur Giner
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia
- Department of Medical Biology, The University of Melbourne, VIC, Australia
| | - Saima Ikram
- Centre of Biotechnology & Microbiology University of Peshawar, Pakistan
| | - Marco J Herold
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia
- Department of Medical Biology, The University of Melbourne, VIC, Australia
| | - Anthony T Papenfuss
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia
- Department of Medical Biology, The University of Melbourne, VIC, Australia
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Haeusler IL, Daniel O, Isitt C, Watts R, Cantrell L, Feng S, Cochet M, Salloum M, Ikram S, Hayter E, Lim S, Hall T, Athaide S, Cosgrove CA, Tregoning JS, Le Doare K. Group B Streptococcus (GBS) colonisation is dynamic over time, whilst GBS capsular polysaccharides-specific antibody remains stable. Clin Exp Immunol 2022; 209:188-200. [PMID: 35802786 PMCID: PMC9390841 DOI: 10.1093/cei/uxac066] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 06/08/2022] [Accepted: 06/27/2022] [Indexed: 11/20/2022] Open
Abstract
Group B Streptococcus (GBS) is a leading cause of adverse pregnancy outcomes due to invasive infection. This study investigated longitudinal variation in GBS rectovaginal colonization, serum and vaginal GBS capsular polysaccharide (CPS)-specific antibody levels. Non-pregnant women were recruited in the UK and were sampled every 2 weeks over a 12-week period. GBS isolates were taken from recto-vaginal swabs and serotyped by polymerase chain reaction. Serum and vaginal immunoglobulin G (IgG) and nasal immunoglobulin A (IgA) specific to CPS were measured by Luminex, and total IgG/A by ELISA. Seventy women were enrolled, of median age 26. Out of the 66 participants who completed at least three visits: 14/47 (29.8%) women that were GBS negative at screening became positive in follow-up visits and 16/19 (84.2%) women who were GBS positive at screening became negative. There was 50% probability of becoming negative 36 days after the first positive swab. The rate of detectable GBS carriage fluctuated over time, although serum, vaginal, and nasal CPS-specific antibody levels remained constant. Levels of CPS-specific antibodies were higher in the serum of individuals colonized with GBS than in non-colonized, but similar in the vaginal and nasal mucosa. We found correlations between antibody levels in serum and the vaginal and nasal mucosa. Our study demonstrates the feasibility of elution methods to retrieve vaginal and nasal antibodies, and the optimization of immunoassays to measure GBS-CPS-specific antibodies. The difference between the dynamics of colonization and antibody response is interesting and further investigation is required for vaccine development.
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Affiliation(s)
- I L Haeusler
- St George's University of London, Paediatric Infectious Diseases Research Group, London, United Kingdom
| | - O Daniel
- St George's University of London, Paediatric Infectious Diseases Research Group, London, United Kingdom
| | - C Isitt
- St George's University of London, The Vaccine Institute, London, United Kingdom
| | - R Watts
- St George's University of London, Paediatric Infectious Diseases Research Group, London, United Kingdom
| | - L Cantrell
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford
| | - S Feng
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford
| | - M Cochet
- St George's University of London, Paediatric Infectious Diseases Research Group, London, United Kingdom
| | - M Salloum
- St George's University of London, Paediatric Infectious Diseases Research Group, London, United Kingdom.,UnivLyon, Claude Bernard University Lyon I, France
| | - S Ikram
- St George's University of London, The Vaccine Institute, London, United Kingdom
| | - E Hayter
- St George's University of London, The Vaccine Institute, London, United Kingdom
| | - S Lim
- St George's University of London, Paediatric Infectious Diseases Research Group, London, United Kingdom
| | - T Hall
- St George's University of London, Paediatric Infectious Diseases Research Group, London, United Kingdom
| | - S Athaide
- St George's University of London, The Vaccine Institute, London, United Kingdom
| | - C A Cosgrove
- St George's University of London, The Vaccine Institute, London, United Kingdom
| | - J S Tregoning
- Imperial College London, Department of Infectious Disease, London, United Kingdom
| | - K Le Doare
- St George's University of London, Paediatric Infectious Diseases Research Group, London, United Kingdom.,Makerere University John Hopkins Research Collaboration, Kampala, Uganda.,Pathogen Immunology Group, United Kingdom Health Security Agency, Porton Down, United Kingdom
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Khattak SU, Lutfullah G, Iqbal Z, Ahmad J, Rehman IU, Shi Y, Ikram S. Aspergillus flavus originated pure compound as a potential antibacterial. BMC Microbiol 2021; 21:322. [PMID: 34798838 PMCID: PMC8605571 DOI: 10.1186/s12866-021-02371-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Accepted: 09/17/2021] [Indexed: 11/20/2022] Open
Abstract
Problem Background Penicillin was the first and most famous fungal secondary metabolite used as broad spectrum antibiotic that revolutionarised pharmaceutical research and also saved millions of lives. The over optimistic belief in 1967 that sufficient antibiotics had been discovered to defeat infectious diseases was quickly crashed with the appearance of multidrug resistant (MDR) bacteria in 1990s. This has posed a serious threat to mankind. Although scientists are making efforts to synthesize and discover new antibiotics there are not enough new drugs in pharmaceutical pipeline to beat the pace at which MDR bacteria are emerging. In view of this there is an urgent and serious medical need for new bioactive compounds to be discovered to treat infections caused by MDR pathogens. The present study is aimed to investigate the antibacterial potential of Aspergillus flavus originated compounds that may act as drug leads to treat future infections. Methodology Among the 6 isolated fungal strains from the rhizosphere of Mentha piperetta, one was processed for isolation of secondary metabolites on the basis of preliminary antibacterial testing. Observation of morphological and microscopic features helped in identification of the fungal strain as Aspergillus flavus. Potato Dextrose Agar (PDA) medium was used for fungal growth while Czapec Yeast Broth (CYB) medium was used for production of fungal metabolites. Column chromatography technique was utilized for purification of compound from crude fungal extract and the mass of the compound was determined using Liquid Chromatography Mass Spectrometry (LCMS) method. Structure elucidation of the pure compound was performed using 500 Varian Nuclear Magnetic Resonance (NMR) machine. Docking was performed using Glide SP algorithm. Agar well diffusion method was used to determine the invitro antibacterial potential of the compound against two MDR bacterial strains i.e. Staphylococcus aureus and Proteus vulgaris. For this a total of 4 dose concentrations i.e. (100, 250, 500, 1000 μg mL− 1) of the compound were prepared and applied to bacterial strains on Mueller Hinton agar using tetracycline as control. Results The chemical name of the purified compound from A. flavus was determined as (2E)-3-[(3S, 4R)-8-hydroxy-3, 4-dimethyl-1-oxo-3, 4-dihydro-1H-2- benzopyran-7-yl] prop-2-enoic acid with the formula C14H14O5 and exact mass of 262.08. The in-Silico analysis showed that this compound has the potential to inhibit the binding pocket of S. aureus TyrRS (1JII) with docking score of − 8.67 Kcal mole− 1. The results obtained from invitro experiments were encouraging as at 1000 μg mL− 1 the compound showed 58.8% inhibition against S. aureus and 28% inhibition against P. vulgaris. Conclusions The pure compound with formula C14H14O5 and exact mass of 262 exhibited antibacterial potential both insilico and invitro against both Gram negative and Gram positive bacteria. The compound was more active against S. aureus in comparison to P. vulgaris. From the obtained results it is concluded that this compound can be used as potent antibacterial candidate but further studies will be needed prior to its use as antibiotic.
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Affiliation(s)
- Saeed Ullah Khattak
- Center of Biotechnology and Microbiology, University of Peshawar, Peshawar, KPK, Pakistan.
| | - Ghosia Lutfullah
- Center of Biotechnology and Microbiology, University of Peshawar, Peshawar, KPK, Pakistan
| | - Zafar Iqbal
- Department of Agricultural Chemistry, University of Agriculture, Peshawar, KPK, Pakistan
| | - Jamshaid Ahmad
- Center of Biotechnology and Microbiology, University of Peshawar, Peshawar, KPK, Pakistan
| | - Irshad Ur Rehman
- Center of Biotechnology and Microbiology, University of Peshawar, Peshawar, KPK, Pakistan
| | - Yanbin Shi
- School of Pharmacy, Lanzhou University, Lanzhou, 730000, People's Republic of China
| | - Saima Ikram
- Center of Biotechnology and Microbiology, University of Peshawar, Peshawar, KPK, Pakistan
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Ahmad F, Ikram S, Ahmad J, ur Rehman I, Khattak SU, Butt S, Mushtaq M. Molecular Docking Unveils Prospective Inhibitors for the SARS-COV-2 Main Protease. SAINS MALAYS 2021. [DOI: 10.17576/jsm-2021-5005-26] [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: 11/17/2022]
Abstract
The recent emergence of a novel coronavirus strain (SARS-CoV-2) has stimulated global efforts to identify potential drugs that target proteins expressed by this novel coronavirus. Among these, the main protease of SARS-CoV-2 (3CL-protease (3CLPro), also known as (MPro) is one of the best choices for the scientists to target. 3CLPro is involved in the processing of polyproteins into mature non-structural viral proteins. An X-ray crystallographic structure (PDB ID 6LU7) of this protein was obtained from the PDB database. ChemDiv libraries of ~80,000 antiviral and ~13,000 coronavirus-targeting molecules were screened against the 3D structure of 3CLPro of SARS-CoV-2. We have identified a panel of molecules that showed an activity and potentially block the active site of the SARS-CoV-2 main protease. These molecules can be investigated further to develop effective virus-inhibiting molecules to treat this highly distressing disease, causing extreme unrest across the globe.
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Ahmad F, Ikram S, Ahmad J, Ullah W, Hassan F, Khattak SU, Irshad Ur Rehman. GASPIDs Versus Non-GASPIDs - Differentiation Based on Machine Learning Approach. Curr Bioinform 2021. [DOI: 10.2174/1574893615999200425225729] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Background:
Peptidases are a group of enzymes which catalyze the cleavage of peptide
bonds. Around 2-3% of the whole genome codes for proteases and about one-third of all known
proteases are serine proteases which are divided into 13 clans and 40 families. They are involved
in diverse physiological roles such as digestion, coagulation of blood, fibrinolysis, processing of
proteins and prohormones, signaling pathways, complement fixation, and have a vital role in the
immune defense system. Based on their functions, they can broadly be divided into two classes;
GASPIDs (Granule Associated Serine Peptidases involved in Immune Defense System) and Non-
GASPIDs. GASPIDs, in particular are involved in immune-associated functions i.e. initiating
apoptosis to kill virally infected and cancerous cells, cytokine modulation for the generation of
inflammatory responses, and direct killing of pathogens through phagosomes.
Methods:
In this study, sequence-based characterization of these two types of serine proteases is
performed. We first identified sequences by analyzing multiple online databases as well as by
analyzing whole genomes of different species from different orthologous and non-orthologous
species. Sequences were identified by devising a distinct criterion to differentiate GASPIDs from
Non-GASPIDs. The translated version of these sequences was then subjected to feature extraction.
Using these distinctive features, we differentiated GASPIDs from Non-GASPIDs by applying
multiple supervised machine learning models.
Results and Conclusion:
Our results show that, among the three classifiers used in this study,
SVM classifier coupled with tripeptide as feature method has shown the best accuracy in
classification of sequences as GASPIDs and Non-GASPIDs.
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Affiliation(s)
- Fawad Ahmad
- Centre of Biotechnology & Microbiology, University of Peshawar, Peshawar, Pakistan
| | - Saima Ikram
- Centre of Biotechnology & Microbiology, University of Peshawar, Peshawar, Pakistan
| | - Jamshaid Ahmad
- Centre of Biotechnology & Microbiology, University of Peshawar, Peshawar, Pakistan
| | - Waseem Ullah
- College of Software Convergence, Sejong University, Seoul, South Korea
| | - Fahad Hassan
- Centre of Biotechnology & Microbiology, University of Peshawar, Peshawar, Pakistan
| | - Saeed Ullah Khattak
- Centre of Biotechnology & Microbiology, University of Peshawar, Peshawar, Pakistan
| | - Irshad Ur Rehman
- Centre of Biotechnology & Microbiology, University of Peshawar, Peshawar, Pakistan
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Ashfaq M, Abid SMA, Rauf K, Alkahraman YM, Haroon MZ, Ahmad F, Ikram S, Ahmad J. Potential Role of Proton Pump Inhibitors Against Human DRD2 Receptor in Drug Induced Hyperprolactinemia. Rev Chim 2020. [DOI: 10.37358/rc.20.10.8362] [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: 11/20/2022]
Abstract
Dopamine is a catecholamine neurotransmitter that control several important functions via different dopamine receptors(D1-D5). The Dopamine (DRD2) receptor and other D2 family receptors (D3 and D4) are predominantly involved in the inhibitory activities. One vital role of dopamine receptors is its involvement in the endocrine regulations including the hormone synthesis and their secretion. The regulation of prolactin hormone is mainly controlled through DRD2 receptors. Blocking the delivery of dopamine at these DRD2 receptors will cause an increase in serum prolactin levels. PPI�s are among the widely prescribed medications used for multiple gastric hypersecretory disorders and are shown to cause increase in serum prolactin level. This study focuses on computational methods to test PPIs interaction with dopamine D2 receptor through molecular docking & dynamics studies. The 3D structure of protein and the drugs were downloaded from PDB and PubChem databases. Protein and ligands were prepared followed by molecular docking. Complexes with best docking poses were then proceeded towards MD simulations of 60 ns. Results were then analyzed. This study confirmed that there is prospective affinity between proton pump inhibitors and dopamine D2 receptor, and dynamically stable complexes are formed after drug-receptor binding. MD simulations results confirmed the binding affinity between PPIs and Dopamine D2 receptor, concluding that the use of PPIs may be involved in drug induced hyperprolactinemia and other related effects.
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Ahmad J, Ikram S, Hafeez AB, Durdagi S. Physics-driven identification of clinically approved and investigation drugs against human neutrophil serine protease 4 (NSP4): A virtual drug repurposing study. J Mol Graph Model 2020; 101:107744. [PMID: 33032202 DOI: 10.1016/j.jmgm.2020.107744] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [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: 02/11/2020] [Revised: 08/29/2020] [Accepted: 08/31/2020] [Indexed: 01/19/2023]
Abstract
Neutrophils synthesize four immune associated serine proteases: Cathepsin G (CTSG), Elastase (ELANE), Proteinase 3 (PRTN3) and Neutrophil Serine Protease 4 (NSP4). While previously considered to be immune modulators, overexpression of neutrophil serine proteases correlates with various disease conditions. Therefore, identifying novel small molecules that can potentially control or inhibit the proteolytic activity of these proteases is crucial to revert or temper the aggravated disease phenotype. To the best of our knowledge, although there is limited data for inhibitors of other neutrophil protease members, there is no previous clinical study of a synthetic small molecule inhibitor targeting NSP4. In this study, an integrated molecular modeling algorithm was performed within a virtual drug repurposing study to identify novel inhibitors for NSP4, using clinically approved and investigation drugs library (∼8000 compounds). Based on our rigorous filtration, we found that following molecules Becatecarin, Iogulamide, Delprostenate and Iralukast are predicted to block the activity of NSP4 by interacting with core catalytic residues. The selected ligands were energetically more favorable compared to the reference molecule. The result of this study identifies promising molecules as potential lead candidates.
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Affiliation(s)
- Jamshaid Ahmad
- Center of Biotechnology & Microbiology, University of Peshawar, Pakistan.
| | - Saima Ikram
- Center of Biotechnology & Microbiology, University of Peshawar, Pakistan; Computational Biology and Molecular Simulations Laboratory, Department of Biophysics, School of Medicine, Bahcesehir University, Istanbul, Turkey
| | - Ahmer Bin Hafeez
- Center of Biotechnology & Microbiology, University of Peshawar, Pakistan
| | - Serdar Durdagi
- Computational Biology and Molecular Simulations Laboratory, Department of Biophysics, School of Medicine, Bahcesehir University, Istanbul, Turkey.
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Ikram S, Ahmad J, Rehman IU, Durdagi S. Potent novel inhibitors against hepatitis C virus NS3 (HCV NS3 GT-3a) protease domain. J Mol Graph Model 2020; 101:107727. [PMID: 33027738 DOI: 10.1016/j.jmgm.2020.107727] [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: 02/08/2020] [Revised: 06/28/2020] [Accepted: 08/20/2020] [Indexed: 12/12/2022]
Abstract
HCV NS3, a non-structural hepatitis C viral protein is used as one of the potential targets for inhibition by direct-acting antivirals. It is known that the success rate for HCV genotype-1 treatment remained very high, however, treatment of genotype-3a (GT-3a), is still quite challenging. In the current study, the HCV GT-3a full-length NS3 gene was amplified and sequenced. The complete nucleotide sequence was translated into the amino acid sequence and homology models of HCV-NS3 GT-3a were generated by HCV-NS3 genotype-1b as a template. The objective of the study was to screen novel therapeutic hits from large databases. For this aim, various small molecule databases including, BindingDB (∼45.000 compounds), NCI (∼265.000 compounds), and Specs-SC (∼212.000 compounds) were used. Firstly, all of the compounds were screened using binary-QSAR models from the MetaCore/MetaDrug server, and compounds were filtered based on therapeutic activity predictions by the anti-viral QSAR model. Filtered molecules were used in 26 different toxicity QSAR models and active non-toxic compounds were identified. These selected molecules were then used in docking and molecular dynamics (MD) simulations studies at the binding cavities of the NS3 protease domain of the GT-3a. Results were compared with known inhibitors and novel molecules are proposed against HCV-NS3 GT-3a. These molecules have high ligand efficiencies as compared to the reference molecules suggesting a better alternate to the existing suite of inhibitors. Thus, this study will be a step ahead in the development of new potential compounds as antiviral drugs for the GT-3a target.
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Affiliation(s)
- Saima Ikram
- Computational Biology and Molecular Simulations Laboratory, Department of Biophysics, School of Medicine, Bahcesehir University, Istanbul, Turkey; Center of Biotechnology & Microbiology, University of Peshawar, Pakistan
| | - Jamshaid Ahmad
- Center of Biotechnology & Microbiology, University of Peshawar, Pakistan.
| | - Irshad-Ur Rehman
- Center of Biotechnology & Microbiology, University of Peshawar, Pakistan
| | - Serdar Durdagi
- Computational Biology and Molecular Simulations Laboratory, Department of Biophysics, School of Medicine, Bahcesehir University, Istanbul, Turkey.
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Ahmad J, Ikram S, Ahmad F, Rehman IU, Mushtaq M. SARS-CoV-2 RNA Dependent RNA polymerase (RdRp) - A drug repurposing study. Heliyon 2020; 6:e04502. [PMID: 32754651 PMCID: PMC7377705 DOI: 10.1016/j.heliyon.2020.e04502] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Revised: 06/18/2020] [Accepted: 07/15/2020] [Indexed: 12/19/2022] Open
Abstract
The outbreak of SARS-CoV-2 in December 2019 in China subsequently lead to a pandemic. Lack of vaccine and specific anti-viral drugs started a global health disaster. For a sustained control and protection, development of potential anti-viral drugs is one of the targeted approach. Although, designing and developing a panel of new drugs molecules are always encouraged. However, in the current emergency, drug repurposing study is one of the most effective and fast track option. The crystal structure of a SARS-CoV-2 (Severe acute respiratory syndrome coronavirus 2) RNA Dependent RNA Polymerase (RdRp) has recently been deciphered through X-ray crystallography. The single-chain of core RNA Dependent RNA Polymerase relies on virus-encoded cofactors nsp7 and two units of nsp8 for its optimum function. This study explored the FDA approved database of 7922 molecules and screened against the core polymerase along with cofactors. Here we report a panel of FDA approved drugs that show substantial interactions with key amino acid residues of the active site. Interestingly, some of the identified drugs (Ornipressin, Lypressin, Examorelin, Polymyxin B1) bind strongly within the binding pockets of both forms of RdRp. Besides, we found strong candidates for the complex form as well which include Nacortocin, Cistinexine, Cisatracurium (among others). These drugs have the potential to be considered while contriving therapeutic options.
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Affiliation(s)
- Jamshaid Ahmad
- Centre of Biotechnology and Microbiology, University of Peshawar, Peshawar, KP, Pakistan
| | - Saima Ikram
- Centre of Biotechnology and Microbiology, University of Peshawar, Peshawar, KP, Pakistan
| | - Fawad Ahmad
- Centre of Biotechnology and Microbiology, University of Peshawar, Peshawar, KP, Pakistan
| | - Irshad Ur Rehman
- Centre of Biotechnology and Microbiology, University of Peshawar, Peshawar, KP, Pakistan
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Patka M, Wallin-Ruschman J, Al Rahma BA, Zar A, Bin Nauman H, Sharif JM, Ikram S, Ul Hasan T, Naeem A, Sharif GM, Mehboob N, Azim T, Khanam Z. 'We need to share our stories': the lives of Pakistanis with intellectual disability and their guardians. J Intellect Disabil Res 2020; 64:345-356. [PMID: 32166785 DOI: 10.1111/jir.12723] [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: 08/01/2019] [Revised: 02/25/2020] [Accepted: 02/26/2020] [Indexed: 06/10/2023]
Abstract
INTRODUCTION The experiences of Pakistanis with intellectual disabilities (IDs) and their family members have been underexplored empirically. METHOD The present study sought to address this gap by understanding the lives of five Special Olympics Pakistan athletes and their guardians through PhotoVoice. FINDINGS Through thematic analysis, we present the primary theme concerning Pakistan's cultural context that provides an empirical exploration of cultural beliefs about intellectual disability, cultural expectations and support received by people with intellectual disabilities and their guardians. DISCUSSION We discuss implications for research and practice.
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Affiliation(s)
- M Patka
- Department of Psychology, Zayed University, Dubai, United Arab Emirates
| | | | - B A Al Rahma
- Department of Psychology, Zayed University, Dubai, United Arab Emirates
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12
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Ikram S, Ahmad J, Durdagi S. Screening of FDA approved drugs for finding potential inhibitors against Granzyme B as a potent drug-repurposing target. J Mol Graph Model 2019; 95:107462. [PMID: 31786094 DOI: 10.1016/j.jmgm.2019.107462] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [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: 06/29/2019] [Revised: 09/12/2019] [Accepted: 09/29/2019] [Indexed: 10/25/2022]
Abstract
Granzyme B is one of the best-characterized and extensively studied member of cytotoxic lymphocytes (CL) proteases. Initially, it is thought to be involved in eliminating virally infected or cancerous cells by using a specialized mechanism through which they are internalized into target cells. In the last decade, however this dimension has changed as there are several reports show that not only CL but also other immune cells can also synthesize Granzyme B. This leads to the possibility of the presence of these proteases in extracellular environment. Being active protease, it then raises the possibility of damaging host tissues as evident from the available reported literature. In many instances, Granzyme B is directly involved in pathogenicity, however in others, it contributes to the disease severity as their over expression makes the clinical situation quite worse which ultimately leads to the chronic state of the disease. Serine protease inhibitor-9 is a natural known intracellular inhibitor of Granzyme B, however there is less data available about the potential inhibitors that can regulate its activity in an extracellular environment. Current study is an effort to identify potential novel inhibitors of Granzyme B. For this aim, drug repurposing study was performed. Around 7900 FDA approved drugs were screened using both ligand- and target-driven approaches. Initially, all molecules were docked using induced fit docking (IFD) approach and selected 318 high-docking scored molecules were used in short (1-ns) molecular dynamics (MD) simulations. Based on MM/GBSA binding free energy calculations, 6 compounds were selected and used in long (100-ns) MD simulations. These compounds were then used in binary QSAR analysis. Therapeutic activity potentials of studied compounds were investigated by Clarivate Analytics's MetaCore/MetaDrug platform which uses binary QSAR models. It is developed based on manually curated database of molecular interactions, molecular pathways, gene-disease associations, chemical metabolism and toxicity information. Results of selected compounds were compared with a positive control molecule. Current drug repurposing study is a step ahead in finding potential lead compounds by screening database of FDA approved molecules. We have identified novel inhibitors (Tannic acid, Mupirocin, Phytonadiol sodium diphosphate, Cefpiramide, Xenazoic acid) that have potential to decrease the activity of Granzyme B.
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Affiliation(s)
- Saima Ikram
- Center of Biotechnology & Microbiology, University of Peshawar, Pakistan; Computational Biology and Molecular Simulations Laboratory, Department of Biophysics, School of Medicine, Bahcesehir University, Istanbul, Turkey
| | - Jamshaid Ahmad
- Center of Biotechnology & Microbiology, University of Peshawar, Pakistan.
| | - Serdar Durdagi
- Computational Biology and Molecular Simulations Laboratory, Department of Biophysics, School of Medicine, Bahcesehir University, Istanbul, Turkey.
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Kiriakidi S, Kolocouris A, Liapakis G, Ikram S, Durdagi S, Mavromoustakos T. Effects of Cholesterol on GPCR Function: Insights from Computational and Experimental Studies. Advances in Experimental Medicine and Biology 2019; 1135:89-103. [DOI: 10.1007/978-3-030-14265-0_5] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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Ikram S, Tani S, Kaur G, Hemadri M. Adult jejunal intussusception : A rare case of intestinal obstruction in adults. Int J Surg 2018. [DOI: 10.1016/j.ijsu.2018.05.130] [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: 10/28/2022]
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15
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Gupta A, Ikram S, Wijesekera V. Infected Chylous Pericardial Tamponade in a Morbidly Obese Patient. Heart Lung Circ 2017. [DOI: 10.1016/j.hlc.2017.06.627] [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: 11/26/2022]
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16
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Clark KA, Ikram S, Evershed RP. The significance of petroleum bitumen in ancient Egyptian mummies. Philos Trans A Math Phys Eng Sci 2016; 374:rsta.2016.0229. [PMID: 27644983 PMCID: PMC5031647 DOI: 10.1098/rsta.2016.0229] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 07/28/2016] [Indexed: 05/28/2023]
Abstract
Mummification was practised in ancient Egypt for more than 3000 years, emerging from initial observations of buried bodies preserved by natural desiccation. The use of organic balms (and other funerary practices) was a later introduction necessitated by more humid burial environments, especially tombs. The dark colour of many mummies led to the assumption that petroleum bitumen (or natural asphalt) was ubiquitous in mummification; however, this has been questioned for more than 100 years. We test this by investigating 91 materials comprising balms, tissues and textiles from 39 mummies dating from ca 3200 BC to AD 395. Targeted petroleum bitumen biomarker (steranes and hopanes) analyses by gas chromatography-mass spectrometry selected ion monitoring (GC-MS SIM, m/z 217 and 191) showed no detectable bitumen use before the New Kingdom (ca 1550-1070 BC). However, bitumen was used in 50% of New Kingdom to Late Period mummies, rising to 87% of Ptolemaic/Roman Period mummies. Quantitative determinations using (14)C analyses reveal that even at peak use balms were never more than 45% w/w bitumen. Critically, the dark colour of balms can be simulated by heating/ageing mixtures of fats, resins and beeswax known to be used in balms. The application of black/dark brown balms to bodies was deliberate after the New Kingdom reflecting changing funerary beliefs and shifts in religious ideology.This article is part of the themed issue 'Quantitative mass spectrometry'.
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Affiliation(s)
- K A Clark
- Organic Geochemistry Unit, School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, UK
| | - S Ikram
- Department of Egyptology, The American University in Cairo, AUC Avenue, PO Box 74, Tagammu 5, New Cairo 11835, Egypt
| | - R P Evershed
- Organic Geochemistry Unit, School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, UK
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Mohsen A, Loughran J, Ikram S. Coronary to extra-cardiac anastomosis. Heart Lung Vessel 2014; 6:208-9. [PMID: 25279364 PMCID: PMC4181283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Rao RAK, Ikram S, Ahmad J. Adsorption of Pb(II) on a composite material prepared from polystyrene-alumina and activated carbon: Kinetic and thermodynamic studies. JICS 2012. [DOI: 10.1007/bf03246548] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Kherro S, Hamid F, Ikram S. P244 B-Lynch brace suture for primary atonic post partum hemorrhage (PPH). Int J Gynaecol Obstet 2009. [DOI: 10.1016/s0020-7292(09)61734-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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21
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Ikram S, Ikram MA, Ikram MK. Paradoxical medicine. West J Med 2008. [DOI: 10.1136/bmj.39514.529375.ad] [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: 11/03/2022]
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22
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Stoddard MF, Wagner SG, Ikram S, Longaker RA, Prince CR. Effects of nifedipine and nitroglycerin on left ventricular systolic dysfunction and impaired diastolic filling after exercise-induced ischemia in humans. J Am Coll Cardiol 1996; 28:915-23. [PMID: 8837569 DOI: 10.1016/s0735-1097(96)00245-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
OBJECTIVES This study sought to determine whether calcium antagonist, compared with nitroglycerin, administration attenuates left ventricular dysfunction after exercise-induced ischemia in humans. BACKGROUND Exercise-induced ischemia impairs left ventricular systolic function and diastolic filling after exercise. The mechanism of this phenomenon is unknown but may relate to intracellular calcium overload. METHODS Echocardiography was performed in 131 patients before and 30 min, 2 h and 4 h after exercise stress test. Ischemia was defined as a reversible thallium stress defect. No medication, sublingual nitroglycerin or nifedipine was randomly given to each patient at peak exercise. RESULTS Isovolumetric relaxation time was significantly prolonged from rest (100 +/- 19 ms [mean +/- SD]) to 30 min (118 +/- 20 ms, p < 0.0005), 2 h (117 +/- 18 ms, p < 0.0005) and 4 h (110 +/- 22 ms, p < 0.05) after exercise in 21 patients with exercise-induced ischemia who received no medication (ischemia-none group). Isovolumetric relaxation time similarly increased after exercise in 23 patients who received nitroglycerin and had exercise-induced ischemia (ischemia-NTG group) but was unchanged in 20 patients with exercise-induced ischemia who received nifedipine (ischemia-nifedipine group). Peak early filling velocity decreased in the ischemia-none and ischemia-NTG groups from rest to 30 min and 2 h after exercise, but peak early filling velocity was unchanged in the ischemia-nifedipine group. Ejection fraction decreased from rest to 30 min after exercise in the ischemia-none group (59 +/- 12% vs. 51 +/- 13%, p < 0.025) and ischemia-NTG group (59 +/- 14% vs. 49 +/- 14%, p < 0.005) but was unchanged in the ischemia-nifedipine group (60 +/- 19% vs. 64 +/- 18%, p = NS). A new regional left ventricular wall motion abnormality occurred more frequently 30 min after exercise in the ischemia-none group (11 [52%] of 21) and ischemia-NTG group (9 [39%] of 23) compared with the ischemia-nifedipine group (2 [10%] of 20, both p < 0.05). No change occurred in left ventricular systolic function and diastolic filling after exercise in the control groups. CONCLUSIONS Exercise-induced ischemia impairs systolic function and diastolic filling after exercise. Sublingual nifedipine but not nitroglycerin attenuates this process and suggests that altered calcium homeostasis may play a role in left ventricular dysfunction that occurs after exercise-induced ischemia.
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Affiliation(s)
- M F Stoddard
- Department of Medicine, University of Louisville, Louisville, Kentucky 40202, USA
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Musumeci F, Shukla V, Mignosa C, Casali G, Ikram S. Early repair of postinfarction ventricular septal defect with gelatin-resorcin-formol biological glue. Ann Thorac Surg 1996; 62:486-8. [PMID: 8694610] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
BACKGROUND Early surgical repair of postinfarction ventricular septal defect has improved early mortality rate. Mortality remains high in patients presenting within 1 week of infarction, or when rupture has occurred in the inferior part of the septum. METHODS We describe a surgical technique for repair of postinfarction ventricular septal defect that involves no infarctectomy: continuous suturing of a bovine pericardial patch to healthy myocardium around the infarcted area and use of gelatin-resorcin-formol biological glue as a sealant between the patch and the interventricular septum. RESULTS We have used this technique successfully in 3 consecutive patients in whom repair was performed within 1 week of myocardial infarction. The rupture of the interventricular septum was located anteriorly in 2 patients and inferiorly in the other. They all made an uneventful recovery, and at follow-up there was no evidence of residual shunt. CONCLUSIONS This technique can be a useful adjunct to the surgical management of this difficult group of patients.
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Affiliation(s)
- F Musumeci
- Department of Cardiac Surgery, University Hospital of Wales, Cardiff, United Kingdom
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Abstract
Deciding whether a patient with sub-optimal mitral valve anatomy will benefit from percutaneous mitral valvotomy remains a demanding clinical problem. We assessed the ability of an established echo score applied to transoesophageal images to predict absolute increases in mitral valve area and improvement in exercise capacity. Twenty five consecutive patients undergoing routine percutaneous mitral valvotomy were studied. Changes in exercise tolerance were measured by serial cardiorespiratory treadmill exercise testing. Before the procedure, exercise duration was directly related to mitral valve area (rs = 0.44, P < 0.05). Following percutaneous mitral valvotomy there was an increase in valve area (0.9 +/- 0.2 to 1.4 +/- 0.3 cm2, P < 0.0001) and repeat exercise testing demonstrated increases in exercise duration (470 +/- 220 to 610 +/- 240 s, P < 0.001) and peak VO2 (12.6 +/- 4.2 to 15.1 +/- 4.5 ml/kg/min, P < 0.01). There was an inverse correlation between the echo score and the increase in valve area (rs = -0.52, P < 0.05) but no relationship between the echo score and the increase in exercise duration or peak minute oxygen consumption (VO2). These data demonstrate that a score applied to transoesophageal images echocardiographic images can predict changes in mitral valve area but that the score fails to predict functional improvement for an individual patient. This suggests, therefore, that patients without contraindications to valvotomy whose valves have a high echo score should still be considered for valvotomy as they may benefit considerably from the procedure.
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Affiliation(s)
- A P Banning
- Department of Cardiology, University Hospital of Wales, Cardiff, UK
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Banning AP, Masani ND, Ikram S, Fraser AG, Hall RJ. Transoesophageal echocardiography as the sole diagnostic investigation in patients with suspected thoracic aortic dissection. Heart 1994; 72:461-5. [PMID: 7818964 PMCID: PMC1025615 DOI: 10.1136/hrt.72.5.461] [Citation(s) in RCA: 31] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
OBJECTIVES To assess the value and limitations of using transoesophageal echocardiography as the sole diagnostic test in patients with suspected thoracic aortic dissection. DESIGN Retrospective data review over a two year period. SETTING A regional cardiothoracic centre. PATIENTS Data were compiled from admission records, surgical records, and lists of patients undergoing diagnostic investigations in the hospital. Patient's notes were used to identify presentation, management, and outcome. INTERVENTIONS Patients were managed according to the policy of our unit, which is to treat patients with dissection affecting the ascending aorta by an operation. Patients with uncomplicated dissection sparing the ascending aorta are initially managed medically. MAIN OUTCOME MEASURES In hospital and two year follow-up of patients who were investigated by transoesophageal echocardiography alone. RESULTS Of 48 patients referred, 45 underwent transoesophageal echocardiography. Dissection was confirmed in 22 patients. Transoesophageal echocardiography showed the proximal extent of the dissection in 21/22 (96%) and only one patient required a further diagnostic investigation. Ten patients with dissection of the ascending aorta underwent graft replacement of the ascending aorta; operative mortality was 10% and their two year survival was 80%. Of the eight patients with dissection of the descending aorta, six were discharged home, and five were alive at two years. No patient without evidence of dissection on their initial transoesophageal echocardiographic examination required re-investigation into possible dissection in the two years after discharge. CONCLUSIONS In patients with suspected thoracic dissection transoesophageal echocardiography rapidly and safely gives all the necessary diagnostic information. Further investigations, including coronary angiography, before surgery are unnecessary.
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Affiliation(s)
- A P Banning
- Department of Cardiology, University Hospital of Wales, Heath Park, Cardiff
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Fraser AG, Ikram S, Bryan AJ, Angelini GD. Echocardiographic evidence of persistent pericardial effusion after open heart surgery. Int J Cardiol 1994; 47:59-65. [PMID: 7868287 DOI: 10.1016/0167-5273(94)90134-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Cross-sectional and M-mode echocardiography were used to review 33 patients 6-28 months (mean 19 months) after open heart surgery. Eleven patients had had echocardiographic signs of pericardial effusion during the first week after open heart surgery (Group A), and 22 had not (Group B). At review, pericardial effusion was found in 73% of subjects in Group A compared with 18% of those in Group B (P < 0.01). On average, posterior effusions were small (mean dimension in systole 0.9 cm) but they were detected reproducibly (interobserver agreement 97%). Anterior echo-free spaces (< 0.5 cm) were found frequently, but interobserver variation in their detection was high (agreement in 68%). Symptoms did not correlate with the presence of a late post-operative effusion but the groups were not matched for rhythm or ventricular function. Five patients in Group A had developed atrial fibrillation in association with their early post-operative effusion, and four of these had persisting atrial fibrillation at this review. These results suggest that echo-free spaces around the heart, suggestive of small pericardial effusions, may persist for many months after open heart surgery.
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Affiliation(s)
- A G Fraser
- Department of Cardiology, University Hospital of Wales, Cardiff, UK
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Maire R, Ikram S, Odemuyiwa O, Groves PH, Lo SV, Banning AP, Hall RJ. Abnormalities of left ventricular flow following mitral valve replacement: a colour flow Doppler study. Eur Heart J 1994; 15:293-302. [PMID: 8013500 DOI: 10.1093/oxfordjournals.eurheartj.a060494] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Left ventricular flow patterns were studied at rest by colour flow Doppler echocardiography in 33 patients with mitral tilting-disc prostheses (group 1), in 38 patients with mitral tissue prostheses (group 2) and in 18 healthy volunteers (controls). A 'crossed' flow pattern was seen in 14 patients with mechanical (42%) and in 15 patients with tissue prostheses (39%). The remaining patients and all controls had either 'parallel' or 'intermediate' flow patterns which were classified as 'normal'. There was a significant correlation between the type of flow pattern and the position of the mitral prosthesis in both study groups. The presence of a crossed flow pattern, however, was not related to functional status (assessed clinically by NYHA class) or to abnormalities on the electrocardiogram. Left atrial size was greater in patients with crossed flow than in those without, but all other echocardiographic parameters were similar. Eight patients with crossed and eight with normal flow patterns underwent treadmill exercise testing; there was no difference between the two groups with regard to exercise performance as determined by exercise duration, maximum oxygen consumption and the ventilatory response to exercise. The results of this study indicate that the pattern of blood flow within the left ventricle may be fundamentally altered by the orientation of both mechanical and tissue prostheses. The presence of a crossed flow pattern is not, however, accompanied by significant deleterious haemodynamic or functional consequences.
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Affiliation(s)
- R Maire
- Department of Cardiology, University Hospital of Wales, Cardiff, U.K
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Miller RL, Ikram S, Armelagos GJ, Walker R, Harer WB, Shiff CJ, Baggett D, Carrigan M, Maret SM. Diagnosis of Plasmodium falciparum infections in mummies using the rapid manual ParaSight-F test. Trans R Soc Trop Med Hyg 1994; 88:31-2. [PMID: 8153990 DOI: 10.1016/0035-9203(94)90484-7] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Affiliation(s)
- R L Miller
- Bioanthropology Foundation Paleoepidemiology Project, Northport, NY 11768
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Groves PH, Ikram S, Ingold U, Hall RJ. Tricuspid regurgitation following mitral valve replacement: an echocardiographic study. J Heart Valve Dis 1993; 2:273-8. [PMID: 8269119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The development of late tricuspid regurgitation following mitral valve replacement is accompanied by a severe reduction in exercise capacity and a poor functional outcome. In this study, we compared the clinical and echocardiographic characteristics of two matched groups with (n = 13) and without (n = 13) clinically significant tricuspid regurgitation. The preoperative pulmonary artery pressures and symptom durations were similar, but tricuspid regurgitation at palpation was detected only in patients who later developed severe tricuspid regurgitation (5/13 vs. 0/13; p < 0.02). None of the patients had echocardiographic evidence of rheumatic tricuspid valve disease at the time of the study, but the tricuspid annular diameter (3.7 +/- 0.5 cm vs. 3.2 +/- 0.4 cm; p < 0.05) and right ventricular diameter (4.9 +/- 0.4 cm vs. 4.0 +/- 0.8 cm; p < 0.01) were greater in patients who had developed severe late tricuspid regurgitation. Echocardiographic parameters of left ventricular function and Doppler estimated pulmonary artery systolic pressures were similar in the two groups, and no evidence of prosthetic dysfunction or aortic valve disease was found. These results imply that late tricuspid regurgitation following mitral valve replacement develops as a result of dilation of the tricuspid annulus associated with right ventricular decompensation. The persistence of uncorrected tricuspid incompetence would seem to be an important contributory factor, and its accurate detection and correction at the time of initial surgery may prove to be the most effective means of preventing the development of this important complication of mitral valve replacement.
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Affiliation(s)
- P H Groves
- Department of Cardiology, University Hospital of Wales, Cardiff, United Kingdom
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Tovey JA, Sundar AS, Ikram S, Smith S, Penny WJ. Human cardiac muscle magnesium and potassium concentrations: can skeletal muscle, mononuclear blood cells, erythrocyte and plasma concentrations provide a surrogate measure? Ann Clin Biochem 1992; 29 ( Pt 4):461-2. [PMID: 1642455 DOI: 10.1177/000456329202900416] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- J A Tovey
- Department of Medical Biochemistry, University Hospital of Wales, Cardiff, UK
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Abstract
Cardiopulmonary bypass immediately post-partum could carry the risk of severe uterine bleeding. We report the case of a woman who successfully underwent emergency replacement of a thrombosed mitral prosthesis immediately after Caesarean section.
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Affiliation(s)
- A M Shah
- Department of Cardiology, University Hospital of Wales, Heath Park, Cardiff, U.K
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Affiliation(s)
- R L Miller
- Laboratory of Parasitology, University of Leiden, Netherlands
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Groves PH, Lewis NP, Ikram S, Maire R, Hall RJ. Reduced exercise capacity in patients with tricuspid regurgitation after successful mitral valve replacement for rheumatic mitral valve disease. Heart 1991; 66:295-301. [PMID: 1747281 PMCID: PMC1024725 DOI: 10.1136/hrt.66.4.295] [Citation(s) in RCA: 93] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
OBJECTIVE To determine how severe tricuspid regurgitation influences exercise capacity and functional state in patients who have undergone successful mitral valve replacement for rheumatic mitral valve disease. DESIGN 9 patients in whom clinically significant tricuspid regurgitation developed late after mitral valve replacement were compared with 9 patients with no clinical evidence of tricuspid regurgitation. The two groups were matched for preoperative clinical and haemodynamic variables. Patients were assessed by conventional echocardiography, Doppler echocardiography, and a maximal treadmill exercise test in which expired gas was monitored by mass spectrometry. SETTING University Hospital of Wales, Cardiff. SUBJECTS 18 patients who had been reviewed regularly since mitral valve replacement. MAIN OUTCOME MEASURE Objective indices of exercise performance including exercise duration, maximal oxygen consumption, anaerobic threshold, and ventilatory response to exercise. RESULTS Mitral valve prosthetic function was normal in all patients and estimated pulmonary artery systolic pressure and left ventricular function were similar in the two groups. Right ventricular diameter (median (range) 5.0 (4.3-5.6) v 3.7 (3.0-5.4) cm, p less than 0.01) and the incidence of paradoxical septal motion (9/9 v 3/9, p less than 0.01) were greater in the group with severe tricuspid regurgitation. Exercise performance--assessed by exercise duration (6.3 (5.0-10.7) v 12.7 (7.2-16.0) min, p less than 0.01), maximum oxygen consumption (11.2 (7.3-17.8) v 17.7 (11.8-21.4) ml min-1 kg-1, p less than 0.01), and anaerobic threshold (8.3 (4.6-11.4) v 0.7 (7.3-15.5) ml min-1 kg-1, p less than 0.05)--was significantly reduced in the group with severe tricuspid regurgitation. The ventilatory response to exercise was greater in patients with tricuspid regurgitation (minute ventilation at the same minute carbon dioxide production (41.0 (29.9-59.5) v 33.6 (26.8-39.3) l/min, p less than 0.01). CONCLUSIONS Clinically significant tricuspid regurgitation may develop late after successful mitral valve replacement and in the absence of residual pulmonary hypertension, prosthetic dysfunction, or significant left ventricular impairment. Patients in whom severe tricuspid regurgitation developed had a considerable reduction in exercise capacity caused by an impaired cardiac output response to exercise and therefore experienced a poor functional outcome. The extent to which this was attributable to the tricuspid regurgitation itself or alternatively to the consequences of right ventricular dysfunction was not clear and requires further investigation.
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Affiliation(s)
- P H Groves
- Department of Cardiology, University Hospital of Wales, Cardiff
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Abstract
Paradoxical embolus, the passage of an embolus from the right to the left side of the circulation, was formerly recognised as a postmortem diagnosis. More recently, survivors with paradoxical embolus have been described. A case of paradoxical embolus is described in which the diagnosis was made clinically, and an imminent further embolus visualised by transoesophageal echocardiography, which was successfully treated surgically. Treatment strategies are discussed.
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Affiliation(s)
- S P Barnard
- Department of Cardiac Surgery, University Hospital of Wales, Cardiff, UK
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Alam M, Ahmad M, Rasheed A, Saleem M, Javaid MK, Ikram S. Biopharmaceutical studies of 3-substituted isatin derivatives. Indian J Exp Biol 1990; 28:940-2. [PMID: 2279766] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The metabolic fate of isatin hydrazone (Ia), isatin-3-thiosemicarbazone (Ib), isatin-3-semicarbazone (Ic), isatin-3-phenylhydrazone (Id), isatin oxime (Ie) and 3-hydroxy-3-acetonyl oxindole (II) was studied in rabbits. The compounds were administered orally in the dose of 300 mg/kg body wt. Isatin anthranilic acid, tryptophan and nicotinic acid were identified as the major metabolites excreted in urine. The 3-hydroxy-3-acetonyl oxindole (II) gave on additional metabolite, oxindole. The major metabolites were separated and identified unambiguously on thin layer silica gel plate. Metabolic pathways have been proposed to explain the biotransformation of the compounds investigated.
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Affiliation(s)
- M Alam
- Department of Pharmacy, University of the Punjab, Lahore-I, Pakistan
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Dotson R, Maguire SM, Hayden J, Larsen A, Ikram S. Brucellosis: an unusual cause of fever in Kentucky. J Ky Med Assoc 1990; 88:389-92. [PMID: 2398309] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Human infection with brucellosis appears to be very uncommon in Kentucky. Only three cases have been reported to the Kentucky Department of Health, Frankfort, in the last 4 years. It is suspected, however, that brucellosis is severely underdiagnosed and under-reported in the United States. A patient recently diagnosed with acute systemic brucellosis reminds us that this illness may still be seen in the Commonwealth.
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Affiliation(s)
- R Dotson
- Department of Internal Medicine, University of Louisville School of Medicine, KY 40292
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37
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Abstract
During urgent cardiac catheterization total occlusion of a severe left main coronary artery stenosis occurred, leading to profound cardiogenic shock. The patient survived, after prompt left main coronary angioplasty was performed, followed by emergency coronary bypass surgery.
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Affiliation(s)
- P H Groves
- Department of Cardiology and Radiology, University Hospital of Wales, Cardiff, U.K
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38
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Abstract
The echocardiographic features of left atrial ball thrombus associated with mitral stenosis are reviewed, and some previously unpublished cross-sectional echocardiographic findings presented. In one patient who had a large free-floating ball thrombus there was variation in its echocardiographic appearance; the thrombus was removed uneventfully at surgery. In another patient who had a pedunculated but immobile ball thrombus, a stalk was identified which attached it to the inter-atrial septum; this patient died suddenly before surgery could be performed, due to detachment of the thrombus and obstruction of the mitral valve orifice. Cross-sectional echocardiography is clearly superior to M-mode imaging in the detection of atrial thrombi, and variable appearances may help differentiation of thrombus from myxoma. Whether or not a ball thrombus appears mobile, emergency thrombectomy and mitral valve replacement is indicated, because of the risk of obstruction of the mitral valve.
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Affiliation(s)
- A G Fraser
- Department of Cardiology, University Hospital of Wales, Health Park, Cardiff, U.K
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Ikram S, Lewis S, Bucknall C, Sram I, Thomas N, Vincent R, Chamberlain D. Treatment of acute myocardial infarction with anisoylated plasminogen streptokinase activator complex. Br Med J (Clin Res Ed) 1986; 293:786-9. [PMID: 3094657 PMCID: PMC1341572 DOI: 10.1136/bmj.293.6550.786] [Citation(s) in RCA: 36] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
A controlled trial in 149 patients admitted to a district hospital with probable myocardial infarction tested the effect of 30 units of anisoylated plasminogen streptokinase activator complex (APSAC) on indices of infarct size. Patients were grouped prospectively according to whether they entered the trial within two and a half hours (early entry) or between two and a half and four hours (late entry) after onset of the symptoms. Sixty seven of 73 patients in the control group showed increased plasma activity of myocardial creatine kinase isoenzyme that was diagnostic of infarction compared with only 60 of 76 who received APSAC. The difference was significant overall but occurred predominantly in the early entry group. The patients who received APSAC had more early ventricular arrhythmias, compatible with reperfusion, and showed greater preservation of R waves during admission to hospital. Unwanted effects were generally minor and more common in the actively managed group than the control group (26% v 3%). After nine to 12 months of follow up 12 patients in the control group had died compared with seven in the actively managed group. The ease of administration and the apparent efficacy of APSAC suggest that it is suitable for use in a district hospital for patients with suspected acute myocardial infarction.
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