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Rajaratnam V, Ng H, Rahman NA, Dong C. Development of a mental script for the mental practice of micro suturing: a methodological approach. Ann R Coll Surg Engl 2021; 104:288-294. [PMID: 34931536 DOI: 10.1308/rcsann.2021.0171] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
INTRODUCTION Motor imagery and mental practice are important for the acquisition and mastery of surgical skills. The success of this technique relies on the use of a well-developed mental script. In this study, we shared how we developed a mental script for basic micro suturing training by using a low-fidelity rubber glove model. METHODS This study applied the design and development research framework. Five expert surgeons developed a mental script by performing a cognitive walkthrough to repair a vertical opening in a rubber glove model, followed by hierarchical task analysis. A draft script was created, and its face and content validity assessed with a checking-back process. Twenty-eight surgeons used the Mental Imagery Questionnaire (MIQ) to assess the validity of the final script. RESULTS The process of developing the mental script is detailed. The assessment by the expert panel showed the mental script had good face and content validity. The mean overall MIQ score was 5.2±1.1 (standard deviation), demonstrating the validity of generating mental imagery from the mental script developed in this study for micro suturing in the rubber glove model. CONCLUSION The methodological approach described in this study is based on a design and development research framework to teach surgical skills. This model is inexpensive and easily accessible, addressing the challenges of reduced opportunities to practise surgical skills. However, although motor skills are important, the surgeon's other non-technical expertise is not addressed with this model. Thus, this model should act as one surgical training approach, but not replace it.
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Affiliation(s)
| | - Hjh Ng
- Khoo Teck Puat Hospital, Singapore
| | | | - C Dong
- Sengkang General Hospital, Singapore
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Rajaratnam V, Rahman NA, Dong C. Integrating instructional design principles into surgical skills training models: an innovative approach. Ann R Coll Surg Engl 2021; 103:718-724. [PMID: 34719953 DOI: 10.1308/rcsann.2020.7132] [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] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
OBJECTIVE Surgical training programmes are evolving from time-based to competency-based schedules, which define expected learning outcomes in surgical knowledge, clinical and technical skills according to training levels. This article aims to review current models in surgical skills acquisition and to propose an integrative process-driven, outcomes-based model for surgical skills acquisition and mastery. DESIGN A literature review was conducted on the theories of motor skills acquisition using PubMed, Web of Science and Google Scholar from 2010 to February 2020. The review was limited to theories and models on surgical skills acquisition and mastery. Four models of surgical skills acquisition were included: Fitts and Posner's three-stage model of motor skills acquisition, Bandura's social learning theory, Ericsson's deliberate practice model and Jeannerod's motor simulation theory. These models are deficient in that there is no universally accessible opportunity to practise the surgical procedure outside of the operating theatre and without access to physical simulators. RESULTS We propose an innovative model that allows deliberate practice of the procedure without the need for expensive physical simulators, and provides an on-demand, self-directed practice by the trainees to achieve the level of mastery. This new model, which incorporates motor imagery and mental practice, augmented by deliberate practice, will provide an alternative training path for expert performance in surgical procedures. CONCLUSIONS The innovative model provides a solution to the reduced opportunity for practice by surgical trainees to achieve mastery in surgical motor skills.
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Affiliation(s)
| | | | - C Dong
- Sengkang General Hospital, Singapore
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Ahmad S, Usman Mirza M, Yean Kee L, Nazir M, Abdul Rahman N, Trant JF, Abdullah I. Fragment-based in silico design of SARS-CoV-2 main protease inhibitors. Chem Biol Drug Des 2021; 98:604-619. [PMID: 34148292 PMCID: PMC8444677 DOI: 10.1111/cbdd.13914] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2021] [Revised: 05/16/2021] [Accepted: 06/06/2021] [Indexed: 11/27/2022]
Abstract
3CLpro is essential for SARS-CoV-2 replication and infection; its inhibition using small molecules is a potential therapeutic strategy. In this study, a comprehensive crystallography-guided fragment-based drug discovery approach was employed to design new inhibitors for SARS-CoV-2 3CLpro. All small molecules co-crystallized with SARS-CoV-2 3CLpro with structures deposited in the Protein Data Bank were used as inputs. Fragments sitting in the binding pocket (87) were grouped into eight geographical types. They were interactively coupled using various synthetically reasonable linkers to generate larger molecules with divalent binding modes taking advantage of two different fragments' interactions. In total, 1,251 compounds were proposed, and 7,158 stereoisomers were screened using Glide (standard precision and extra precision), AutoDock Vina, and Prime MMGBSA. The top 22 hits having conformations approaching the linear combination of their constituent fragments were selected for MD simulation on Desmond. MD simulation suggested 15 of these did adopt conformations very close to their constituent pieces with far higher binding affinity than either constituent domain alone. These structures could provide a starting point for the further design of SARS-CoV-2 3CLpro inhibitors with improved binding, and structures are provided.
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Affiliation(s)
- Sarfraz Ahmad
- Drug Design Development Research GroupDepartment of ChemistryFaculty of ScienceUniversiti MalayaKuala LumpurMalaysia
| | | | - Lee Yean Kee
- Drug Design Development Research GroupDepartment of ChemistryFaculty of ScienceUniversiti MalayaKuala LumpurMalaysia
| | - Mamoona Nazir
- Department of PharmacyThe University of LahoreLahorePakistan
| | - Noorsaadah Abdul Rahman
- Drug Design Development Research GroupDepartment of ChemistryFaculty of ScienceUniversiti MalayaKuala LumpurMalaysia
| | - John F. Trant
- Department of Chemistry and BiochemistryUniversity of WindsorWindsorONCanada
| | - Iskandar Abdullah
- Drug Design Development Research GroupDepartment of ChemistryFaculty of ScienceUniversiti MalayaKuala LumpurMalaysia
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Niemelä E, Desai D, Niemi R, Doroszko M, Özliseli E, Kemppainen K, Rahman NA, Sahlgren C, Törnquist K, Eriksson JE, Rosenholm JM. Nanoparticles carrying fingolimod and methotrexate enables targeted induction of apoptosis and immobilization of invasive thyroid cancer. Eur J Pharm Biopharm 2020; 148:1-9. [PMID: 31917332 DOI: 10.1016/j.ejpb.2019.12.015] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [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: 08/02/2019] [Revised: 11/29/2019] [Accepted: 12/30/2019] [Indexed: 02/08/2023]
Abstract
Metastatic tumors are the main cause of cancer-related death, as the invading cancer cells disrupt normal functions of distant organs and are nearly impossible to eradicate by traditional cancer therapeutics. This is of special concern when the cancer has created multiple metastases and extensive surgery would be too dangerous to execute. Therefore, combination chemotherapy is often the selected treatment form. However, drug cocktails often have severe adverse effects on healthy cells, whereby the development of targeted drug delivery could minimize side-effects of drugs and increase the efficacy of the combination therapy. In this study, we utilized the folate antagonist methotrexate (MTX) as targeting ligand conjugated onto mesoporous silica nanoparticles (MSNs) for selective eradication of folate receptor-expressing invasive thyroid cancer cells. The MSNs was subsequently loaded with the drug fingolimod (FTY720), which has previously been shown to efficiently inhibit proliferation and invasion of aggressive thyroid cancer cells. To assess the efficiency of our carrier system, comprehensive in vitro methods were employed; including flow cytometry, confocal microscopy, viability assays, invasion assay, and label-free imaging techniques. The in vitro results show that MTX-conjugated and FTY720-loaded MSNs potently attenuated both the proliferation and invasion of the cancerous thyroid cells while keeping the off-target effects in normal thyroid cells reasonably low. For a more physiologically relevant in vivo approach we utilized the chick chorioallantoic membrane (CAM) assay, showing decreased invasive behavior of the thyroid derived xenografts and an increased necrotic phenotype compared to tumors that received the free drug cocktail. Thus, the developed multidrug-loaded MSNs effectively induced apoptosis and immobilization of invasive thyroid cancer cells, and could potentially be used as a carrier system for targeted drug delivery for the treatment of diverse forms of aggressive cancers that expresses folate receptors.
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Affiliation(s)
- E Niemelä
- Cell Biology, Faculty of Science and Engineering, Åbo Akademi University, Turku, Finland; Turku Bioscience Centre, University of Turku and Åbo Akademi University, Turku, Finland
| | - D Desai
- Pharmaceutical Sciences Laboratory, Faculty of Science and Engineering, Åbo Akademi University, Turku, Finland
| | - R Niemi
- Cell Biology, Faculty of Science and Engineering, Åbo Akademi University, Turku, Finland
| | - M Doroszko
- Institute of Biomedicine, University of Turku, Finland; Department of Immunology, Genetics and Pathology, Section for Neuro-oncology, Uppsala University, Sweden
| | - E Özliseli
- Pharmaceutical Sciences Laboratory, Faculty of Science and Engineering, Åbo Akademi University, Turku, Finland
| | - K Kemppainen
- Cell Biology, Faculty of Science and Engineering, Åbo Akademi University, Turku, Finland
| | - N A Rahman
- Institute of Biomedicine, University of Turku, Finland; Department of Reproduction and Gynecological Endocrinology, Medical University of Bialystok, Poland
| | - C Sahlgren
- Cell Biology, Faculty of Science and Engineering, Åbo Akademi University, Turku, Finland; Turku Bioscience Centre, University of Turku and Åbo Akademi University, Turku, Finland; Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, the Netherlands
| | - K Törnquist
- Cell Biology, Faculty of Science and Engineering, Åbo Akademi University, Turku, Finland; Minerva Foundation Institute for Medical Research, Biomedicum, Helsinki, Finland
| | - J E Eriksson
- Cell Biology, Faculty of Science and Engineering, Åbo Akademi University, Turku, Finland; Turku Bioscience Centre, University of Turku and Åbo Akademi University, Turku, Finland.
| | - J M Rosenholm
- Pharmaceutical Sciences Laboratory, Faculty of Science and Engineering, Åbo Akademi University, Turku, Finland.
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Abdullah AA, Lee YK, Chin SP, Lim SK, Lee VS, Othman R, Othman S, Rahman NA, Yusof R, Heh CH. Discovery of Dengue Virus Inhibitors. Curr Med Chem 2020; 27:4945-5036. [PMID: 30514185 DOI: 10.2174/0929867326666181204155336] [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] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Revised: 11/11/2018] [Accepted: 11/22/2018] [Indexed: 11/22/2022]
Abstract
To date, there is still no approved anti-dengue agent to treat dengue infection in the market. Although the only licensed dengue vaccine, Dengvaxia is available, its protective efficacy against serotypes 1 and 2 of dengue virus was reported to be lower than serotypes 3 and 4. Moreover, according to WHO, the risk of being hospitalized and having severe dengue increased in seronegative individuals after they received Dengvaxia vaccination. Nevertheless, various studies had been carried out in search of dengue virus inhibitors. These studies focused on the structural (C, prM, E) and non-structural proteins (NS1, NS2A, NS2B, NS3, NS4A, NS4B and NS5) of dengue virus as well as host factors as drug targets. Hence, this article provides an overall up-to-date review of the discovery of dengue virus inhibitors that are only targeting the structural and non-structural viral proteins as drug targets.
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Affiliation(s)
- Adib Afandi Abdullah
- Drug Design and Development Research Group (DDDRG), University of Malaya, Kuala Lumpur, Malaysia
| | - Yean Kee Lee
- Drug Design and Development Research Group (DDDRG), University of Malaya, Kuala Lumpur, Malaysia
| | - Sek Peng Chin
- Drug Design and Development Research Group (DDDRG), University of Malaya, Kuala Lumpur, Malaysia
| | - See Khai Lim
- Drug Design and Development Research Group (DDDRG), University of Malaya, Kuala Lumpur, Malaysia
| | - Vannajan Sanghiran Lee
- Drug Design and Development Research Group (DDDRG), University of Malaya, Kuala Lumpur, Malaysia
| | - Rozana Othman
- Drug Design and Development Research Group (DDDRG), University of Malaya, Kuala Lumpur, Malaysia
| | - Shatrah Othman
- Drug Design and Development Research Group (DDDRG), University of Malaya, Kuala Lumpur, Malaysia
| | - Noorsaadah Abdul Rahman
- Drug Design and Development Research Group (DDDRG), University of Malaya, Kuala Lumpur, Malaysia
| | - Rohana Yusof
- Drug Design and Development Research Group (DDDRG), University of Malaya, Kuala Lumpur, Malaysia
| | - Choon Han Heh
- Drug Design and Development Research Group (DDDRG), University of Malaya, Kuala Lumpur, Malaysia
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Dabbagh A, Hedayatnasab Z, Karimian H, Sarraf M, Yeong CH, Madaah Hosseini HR, Abu Kasim NH, Wong TW, Rahman NA. Polyethylene glycol-coated porous magnetic nanoparticles for targeted delivery of chemotherapeutics under magnetic hyperthermia condition. Int J Hyperthermia 2018; 36:104-114. [PMID: 30428737 DOI: 10.1080/02656736.2018.1536809] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
PURPOSE Although magnetite nanoparticles (MNPs) are promising agents for hyperthermia therapy, insufficient drug encapsulation efficacies inhibit their application as nanocarriers in the targeted drug delivery systems. In this study, porous magnetite nanoparticles (PMNPs) were synthesized and coated with a thermosensitive polymeric shell to obtain a synergistic effect of hyperthermia and chemotherapy. MATERIALS AND METHODS PMNPs were produced using cetyltrimethyl ammonium bromide template and then coated by a polyethylene glycol layer with molecular weight of 1500 Da (PEG1500) and phase transition temperature of 48 ± 2 °C to endow a thermosensitive behavior. The profile of drug release from the nanostructure was studied at various hyperthermia conditions generated by waterbath, magnetic resonance-guided focused ultrasound (MRgFUS), and alternating magnetic field (AMF). The in vitro cytotoxicity and hyperthermia efficacy of the doxorubicin-loaded nanoparticles (DOX-PEG1500-PMNPs) were assessed using human lung adenocarcinoma (A549) cells. RESULTS Heat treatment of DOX-PEG1500-PMNPs containing 235 ± 26 mg·g-1 DOX at 48 °C by waterbath, MRgFUS, and AMF, respectively led to 71 ± 4%, 48 ± 3%, and 74 ± 5% drug release. Hyperthermia treatment of the A549 cells using DOX-PEG1500-PMNPs led to 77% decrease in the cell viability due to the synergistic effects of magnetic hyperthermia and chemotherapy. CONCLUSION The large pores generated in the PMNPs structure could provide a sufficient space for encapsulation of the chemotherapeutics as well as fast drug encapsulation and release kinetics, which together with thermosensitive characteristics of the PEG1500 shell, make DOX-PEG1500-PMNPs promising adjuvants to the magnetic hyperthermia modality.
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Affiliation(s)
- Ali Dabbagh
- a School of Medicine, Faculty of Health and Medical Sciences , Taylor's University , Subang Jaya , Malaysia.,b Department of Materials Science and Engineering , Sharif University of Technology , Tehran , Iran
| | - Ziba Hedayatnasab
- c Department of Chemical Engineering, Faculty of Engineering , University of Malaya , Kuala Lumpur , Malaysia
| | - Hamed Karimian
- a School of Medicine, Faculty of Health and Medical Sciences , Taylor's University , Subang Jaya , Malaysia
| | - Masoud Sarraf
- d Department of Mechanical Engineering, Faculty of Engineering , University of Malaya , Kuala Lumpur , Malaysia
| | - Chai Hong Yeong
- a School of Medicine, Faculty of Health and Medical Sciences , Taylor's University , Subang Jaya , Malaysia
| | | | - Noor Hayaty Abu Kasim
- e Department of Restorative Dentistry, Faculty of Dentistry , University of Malaya , Kuala Lumpur , Malaysia.,f Health and Well-being Research Cluster, Institute of Research Management and Services , University of Malaya , Kuala Lumpur , Malaysia
| | - Tin Wui Wong
- g Non-Destructive Biomedical and Pharmaceutical Research Centre, iPROMISE , Universiti Teknologi MARA, Puncak Alam , Selangor , Malaysia
| | - Noorsaadah Abdul Rahman
- h Department of Chemistry, Faculty of Science , University of Malaya , Kuala Lumpur , Malaysia
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Paiman MES, Hamzah NS, Idris SS, Rahman NA, Ismail K. Synergistic Effect of Co-utilization of Coal and Biomass Char: An Overview. ACTA ACUST UNITED AC 2018. [DOI: 10.1088/1757-899x/358/1/012003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Tan WL, Lee YK, Ho YF, Yusof R, Abdul Rahman N, Karsani SA. Comparative proteomics reveals that YK51, a 4-Hydroxypandurantin-A analogue, downregulates the expression of proteins associated with dengue virus infection. PeerJ 2018; 5:e3939. [PMID: 29404200 PMCID: PMC5796277 DOI: 10.7717/peerj.3939] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [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: 06/13/2017] [Accepted: 09/25/2017] [Indexed: 11/20/2022] Open
Abstract
Dengue is endemic throughout tropical and subtropical regions of the world. Currently, there is no clinically approved therapeutic drug available for this acute viral infection. Although the first dengue vaccine Dengvaxia has been approved for use in certain countries, it is limited to those without a previous dengue infection while the safety and efficacy of the vaccine in those elderly and younger children still need to be identified. Therefore, it is becoming increasingly important to develop therapeutics/drugs to combat dengue virus (DENV) infection. YK51 is a synthetic analogue of 4-Hydroxypandurantin A (a compound found in the crude extract of the rhizomes of Boesenbergia rotunda) that has been extensively studied by our research group. It has been shown to possess outstanding antiviral activity due to its inhibitory activity against NS2B/NS3 DENV2 protease. However, it is not known how YK51 affects the proteome of DENV infected cells. Therefore, we performed a comparative proteomics analysis to identify changes in protein expression in DENV infected HepG2 cells treated with YK51. Classical two-dimensional gel electrophoresis followed by protein identification using tandem mass spectrometry was employed in this study. Thirty proteins were found to be down-regulated with YK51 treatment. In silico analysis predicted that the down-regulation of eight of these proteins may inhibit viral infection. Our results suggested that apart from inhibiting the NS2B/NS3 DENV2 protease, YK51 may also be causing the down-regulation of a number of proteins that may be responsible in, and/or essential to virus infection. However, functional characterization of these proteins will be necessary before we can conclusively determine their roles in DENV infection.
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Affiliation(s)
- Wei-Lian Tan
- Institute of Biological Sciences, Faculty of Science, University of Malaya, Kuala Lumpur, Malaysia
- Drug Design and Development Research Group (DDDRG), University of Malaya, Kuala Lumpur, Malaysia
| | - Yean Kee Lee
- Department of Chemistry, Faculty of Science, University of Malaya, Kuala Lumpur, Malaysia
| | - Yen Fong Ho
- Institute of Biological Sciences, Faculty of Science, University of Malaya, Kuala Lumpur, Malaysia
| | - Rohana Yusof
- Drug Design and Development Research Group (DDDRG), University of Malaya, Kuala Lumpur, Malaysia
- Department of Molecular Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Noorsaadah Abdul Rahman
- Drug Design and Development Research Group (DDDRG), University of Malaya, Kuala Lumpur, Malaysia
- Department of Chemistry, Faculty of Science, University of Malaya, Kuala Lumpur, Malaysia
| | - Saiful Anuar Karsani
- Institute of Biological Sciences, Faculty of Science, University of Malaya, Kuala Lumpur, Malaysia
- Drug Design and Development Research Group (DDDRG), University of Malaya, Kuala Lumpur, Malaysia
- University of Malaya Centre for Proteomics Research (UMCPR), Medical Biotechnology Laboratory, University of Malaya, Kuala Lumpur, Malaysia
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Shamsul NS, Kamarudin SK, Rahman NA. Study on the physical and chemical composition of agro wastes for the production of 5-hydroxymethylfurfural. Bioresour Technol 2018; 247:821-828. [PMID: 30060418 DOI: 10.1016/j.biortech.2017.09.140] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [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: 07/10/2017] [Revised: 09/19/2017] [Accepted: 09/20/2017] [Indexed: 06/08/2023]
Abstract
Treated sludge, goat manure, sugarcane bagasse, empty fruit bunches of oil palm (EFBP) and dry leaves are agro wastes that have high potential for use as feedstocks for the production of 5-hydroxymethylfurfural (5-HMF). The focus of this study is to investigate the production of 5-HMF from agro wastes via co-hydrothermal (CHT) treatment and extraction. Present study include examine on agro waste's physical and chemical properties and also their thermal degradation behaviour. The analysis of the bio-oil products is conducted by FTIR and GC-MS. Co-hydrothermal experiments were conducted at a temperature of 300°C with an experimental time of 15min, followed by alcohol extraction. Highest carbon and hydrogen content are 45.94% and 6.49% (dry leaves) with maximum high heating value 18.39MJ/kg (dry leaves) and fix carbon value 6.60 (goat manure). Through CHT about 39% 5-HMF, 22.97% carboxylic acids, 0.97% of aromatic and 0.73% aldehyde obtained.
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Affiliation(s)
- N S Shamsul
- Department of Chemical and Process, Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor, Malaysia
| | - S K Kamarudin
- Department of Chemical and Process, Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor, Malaysia; Fuel Cell Institute, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor, Malaysia.
| | - N A Rahman
- Department of Chemical and Process, Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor, Malaysia
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Yeong KY, Tan SC, Mai CW, Leong CO, Chung FFL, Lee YK, Chee CF, Abdul Rahman N. Contrasting sirtuin and poly(ADP-ribose)polymerase activities of selected 2,4,6-trisubstituted benzimidazoles. Chem Biol Drug Des 2018; 91:213-219. [PMID: 28719017 DOI: 10.1111/cbdd.13072] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2017] [Revised: 06/10/2017] [Accepted: 07/08/2017] [Indexed: 02/05/2023]
Abstract
Both sirtuin and poly(ADP-ribose)polymerase (PARP) family of enzymes utilize NAD+ as co-substrate. Inhibitors of sirtuins and PARPs are important tools in drug discovery as they are reported to be linked to multiple diseases such as cancer. New potent sirtuin inhibitors (2,4,6-trisubstituted benzimidazole) were discovered from reported PARP inhibitor scaffold. Interestingly, the synthesized compounds have contrasting sirtuin and PARP-1 inhibitory activities. We showed that modification on benzimidazoles may alter their selectivity toward sirtuin or PARP-1 enzymes. This offers an opportunity for further discovery and development of new promising sirtuin inhibitors. Molecular docking studies were carried out to aid the rationalization of these observations. Preliminary antiproliferative studies of selected compounds against nasopharyngeal cancer cells also showed relatively promising results.
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Affiliation(s)
- Keng Yoon Yeong
- School of Science, Monash University Malaysia Campus, Bandar Sunway, Selangor, Malaysia
- Institute for Research in Molecular Medicine, Universiti Sains Malaysia, Minden, Penang, Malaysia
| | - Soo Choon Tan
- Institute for Research in Molecular Medicine, Universiti Sains Malaysia, Minden, Penang, Malaysia
| | - Chun-Wai Mai
- School of Pharmacy, International Medical University, Kuala Lumpur, Malaysia
| | - Chee-Onn Leong
- School of Pharmacy, International Medical University, Kuala Lumpur, Malaysia
- Center for Cancer and Stem Cell Research, International Medical University, Kuala Lumpur, Malaysia
| | - Felicia Fei-Lei Chung
- Center for Cancer and Stem Cell Research, International Medical University, Kuala Lumpur, Malaysia
| | - Yean Kee Lee
- Department of Chemistry, University of Malaya, Kuala Lumpur, Malaysia
| | - Chin Fei Chee
- Department of Chemistry, University of Malaya, Kuala Lumpur, Malaysia
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Frimayanti N, Iskandar B, Yaeghoobi M, Han HC, M. Zain S, Yusof R, Rahman NA. Docking, synthesis and bioassay studies of imine derivatives as potential inhibitors for dengue NS2B/ NS3 serine protease. APJTD 2017. [DOI: 10.12980/apjtd.7.2017d7-177] [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: 10/18/2022]
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Dabbagh A, Abu Kasim NH, Yeong CH, Wong TW, Abdul Rahman N. Critical Parameters for Particle-Based Pulmonary Delivery of Chemotherapeutics. J Aerosol Med Pulm Drug Deliv 2017; 31:139-154. [PMID: 29022837 DOI: 10.1089/jamp.2017.1382] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Targeted delivery of chemotherapeutics through the respiratory system is a potential approach to improve drug accumulation in the lung tumor, while decreasing their negative side effects. However, elimination by the pulmonary clearance mechanisms, including the mucociliary transport system, and ingestion by the alveolar macrophages, rapid absorption into the blood, enzymatic degradation, and low control over the deposition rate and location remain the main complications for achieving an effective pulmonary drug delivery. Therefore, particle-based delivery systems have emerged to minimize pulmonary clearance mechanisms, enhance drug therapeutic efficacy, and control the release behavior. A successful implementation of a particle-based delivery system requires understanding the influential parameters in terms of drug carrier, inhalation technology, and health status of the patient's respiratory system. This review aims at investigating the parameters that significantly drive the clinical outcomes of various particle-based pulmonary delivery systems. This should aid clinicians in appropriate selection of a delivery system according to their clinical setting. It will also guide researchers in addressing the remaining challenges that need to be overcome to enhance the efficiency of current pulmonary delivery systems for aerosols.
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Affiliation(s)
- Ali Dabbagh
- 1 Wellness Research Cluster, Institute of Research Management and Services, University of Malaya , Kuala Lumpur, Malaysia
| | - Noor Hayaty Abu Kasim
- 1 Wellness Research Cluster, Institute of Research Management and Services, University of Malaya , Kuala Lumpur, Malaysia
| | - Chai Hong Yeong
- 2 Department of Biomedical Imaging, Faculty of Medicine, University of Malaya , Kuala Lumpur, Malaysia
| | - Tin Wui Wong
- 3 Department of Pharmaceutics and Pharmaceutical Biotechnology, Faculty of Pharmacy, Universiti Teknologi MARA , Puncak Alam, Malaysia
| | - Noorsaadah Abdul Rahman
- 4 Department of Chemistry, Faculty of Science, University of Malaya , Kuala Lumpur, Malaysia .,5 Drug Design and Development Research Group (DDDRG), University of Malaya , Kuala Lumpur, Malaysia
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Gan CS, Lee YK, Heh CH, Rahman NA, Yusof R, Othman S. The synthetic molecules YK51 and YK73 attenuate replication of dengue virus serotype 2. Trop Biomed 2017; 34:270-283. [PMID: 33593007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Dengue virus infection has been posing alarming economic and social burden on affected nations. It is estimated that 50-100 million dengue infections occur annually with over 2.5 billion people at risk for endemic transmission. In the effort to develop effective antiviral agents, we previously reported potential antiviral activities from selected array of natural products and compounds against dengue virus serotype 2 (DV2). In this study, we report the synthesis of two efficacious novel compounds, YK51 and YK73, and their activities against DV2 replication. Both compounds were chemically synthesised from nicotinic acid using a modified method for the synthesis of dihydropyridine. The products were tested with cell-based assays against DV2 followed by a serine protease assay. As a result, both YK51 and YK73 exhibited intriguing antiviral properties with EC50 of 3.2 and 2.4 µM, respectively. In addition, YK51 and YK73 were found to attenuate the synthesis of intracellular viral RNA and protect the switching of non-classic mechanism of protein translation. These compounds demonstrated inhibitory properties toward the activity of DV2 serine protease in a dose dependent manner. These findings demonstrate that both YK51 and YK73 serve as DV2 serine protease inhibitors that abrogate viral RNA synthesis and translation. Further investigation on these compounds to corroborate its therapeutic properties towards dengue is warranted.
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Affiliation(s)
- C S Gan
- Department of Molecular Medicine, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
- Drug Design and Development Research Group, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Y K Lee
- Department of Chemistry, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia
- Drug Design and Development Research Group, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - C H Heh
- Drug Design and Development Research Group, University of Malaya, 50603 Kuala Lumpur, Malaysia
- Department of Pharmacy, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - N A Rahman
- Department of Chemistry, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia
- Drug Design and Development Research Group, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - R Yusof
- Department of Molecular Medicine, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
- Drug Design and Development Research Group, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - S Othman
- Department of Molecular Medicine, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
- Drug Design and Development Research Group, University of Malaya, 50603 Kuala Lumpur, Malaysia
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Graubner FR, Reichler IM, Rahman NA, Payan-Carreira R, Boos A, Kowalewski MP. Decidualization of the canine uterus: From early until late gestational in vivo morphological observations, and functional characterization of immortalized canine uterine stromal cell lines. Reprod Domest Anim 2016; 52 Suppl 2:137-147. [PMID: 27862405 DOI: 10.1111/rda.12849] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The apparent lack of classical mechanisms for maternal recognition of pregnancy is one of the most intriguing features of canine reproduction. Consequently, similar levels of circulating luteal steroids are observed in pregnant and non-pregnant dogs. However, the early pre-implantation canine embryo locally modulates uterine responses to its presence, facilitating the successful onset of pregnancy. As a part of this interaction, the canine uterus undergoes a species-specific decidualization. Maternal stroma-derived decidual cells develop, the only cells of the canine placenta expressing progesterone receptor (PGR). There exists an acute need for an in vitro stable cell line model for canine decidualization. Therefore, herein our goal was to establish, immortalize and characterize such a cell line. We immortalized three monolayer dog uterine stromal (DUS) cell lines by stably transfecting them with SV40Tag oncogene. Cells retained their mesenchymal character for over 30 passages, as evidenced by VIMENTIN staining. Genomic incorporation of the SV40Tag protein was confirmed by immunofluorescence and Western blot analyses. Cells submitted to a classical in vitro decidualization protocol (N6,2'-O-dibutyryladenosine-3',5'-cyclic monophosphate) revealed upregulated gene levels of selected major decidualization markers (e.g. PRLR, PGR, IGF1, PTGES). Additionally, the basic decidualization capability of PGE2 was demonstrated, revealing increased levels of, for example, PGR and PRLR gene expression, thereby implying its involvement in the progesterone-dependent decidualization in the canine uterus. In summary, our in vitro model with immortalized DUS cell line could serve as an ideal and unique model to study the underlying molecular and endocrine mechanisms of canine decidualization.
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Affiliation(s)
- F R Graubner
- Institute of Veterinary Anatomy, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
| | - I M Reichler
- Clinic of Reproductive Medicine, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
| | - N A Rahman
- Department of Physiology, Institute of Biomedicine, University of Turku, Turku, Finland
| | - R Payan-Carreira
- Centro de Ciência Animal e Veterinária (CECAV), Zootecnia Department, University of Trás-os-Montes and Alto Douro, Vila Real, Portugal
| | - A Boos
- Institute of Veterinary Anatomy, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
| | - M P Kowalewski
- Institute of Veterinary Anatomy, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
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Yehye WA, Abdul Rahman N, Saad O, Ariffin A, Abd Hamid SB, Alhadi AA, Kadir FA, Yaeghoobi M, Matlob AA. Rational Design and Synthesis of New, High Efficiency, Multipotent Schiff Base-1,2,4-triazole Antioxidants Bearing Butylated Hydroxytoluene Moieties. Molecules 2016; 21:E847. [PMID: 27367658 PMCID: PMC6273539 DOI: 10.3390/molecules21070847] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2016] [Revised: 06/22/2016] [Accepted: 06/24/2016] [Indexed: 11/16/2022] Open
Abstract
A new series of multipotent antioxidants (MPAOs), namely Schiff base-1,2,4-triazoles attached to the oxygen-derived free radical scavenging moiety butylated hydroxytoluene (BHT) were designed and subsequently synthesized. The structure-activity relationship (SAR) of the designed antioxidants was established alongside the prediction of activity spectra for substances (PASS). The antioxidant activities of the synthesized compounds 4-10 were tested by the DPPH bioassay. The synthesized compounds 4-10 inhibited stable DPPH free radicals at a level that is 10(-4) M more than the well-known standard antioxidant BHT. Compounds 8-10 with para-substituents were less active than compounds 4 and 5 with trimethoxy substituents compared to those with a second BHT moiety (compounds 6 and 7). With an IC50 of 46.13 ± 0.31 µM, compound 6 exhibited the most promising in vitro inhibition at 89%. Therefore, novel MPAOs containing active triazole rings, thioethers, Schiff bases, and BHT moieties are suggested as potential antioxidants for inhibiting oxidative stress processes and scavenging free radicals, hence, this combination of functions is anticipated to play a vital role in repairing cellular damage, preventing various human diseases and in medical therapeutic applications.
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Affiliation(s)
- Wageeh A Yehye
- Nanotechnology & Catalysis Research Centre (NANOCAT), University of Malaya, Block 3A, Institute of Postgraduate Studies Building, Kuala Lumpur 50603, Malaysia.
| | - Noorsaadah Abdul Rahman
- Department of Chemistry, Faculty of Science, University of Malaya, Kuala Lumpur 50603, Malaysia.
- Drug Design and Development Research Group, Department of Chemistry, Faculty of Science, University of Malaya, Kuala Lumpur 50603, Malaysia.
| | - Omar Saad
- Department of Pharmacy, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia.
| | - Azhar Ariffin
- Department of Chemistry, Faculty of Science, University of Malaya, Kuala Lumpur 50603, Malaysia.
| | - Sharifah Bee Abd Hamid
- Nanotechnology & Catalysis Research Centre (NANOCAT), University of Malaya, Block 3A, Institute of Postgraduate Studies Building, Kuala Lumpur 50603, Malaysia.
| | - Abeer A Alhadi
- Department of Chemistry, Faculty of Science, University of Malaya, Kuala Lumpur 50603, Malaysia.
- Drug Design and Development Research Group, Department of Chemistry, Faculty of Science, University of Malaya, Kuala Lumpur 50603, Malaysia.
| | - Farkaad A Kadir
- Division of Human Biology, School of Medicine, International Medical University, Kuala Lumpur 57000, Malaysia.
| | - Marzieh Yaeghoobi
- Department of Chemistry, Faculty of Science, University of Malaya, Kuala Lumpur 50603, Malaysia.
- Drug Design and Development Research Group, Department of Chemistry, Faculty of Science, University of Malaya, Kuala Lumpur 50603, Malaysia.
| | - Abdulsalam A Matlob
- Department of Environmental Technology, College of Environment, Mosul University, Mosul 41001, Iraq.
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Yehye WA, Rahman NA, Ariffin A, Abd Hamid SB, Alhadi AA, Kadir FA, Yaeghoobi M. ChemInform Abstract: Understanding the Chemistry Behind the Antioxidant Activities of Butylated Hydroxytoluene (BHT): A Review. ChemInform 2015; 46:no-no. [DOI: 10.1002/chin.201541253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
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Yehye WA, Rahman NA, Ariffin A, Abd Hamid SB, Alhadi AA, Kadir FA, Yaeghoobi M. Understanding the chemistry behind the antioxidant activities of butylated hydroxytoluene (BHT): a review. Eur J Med Chem 2015; 101:295-312. [PMID: 26150290 DOI: 10.1016/j.ejmech.2015.06.026] [Citation(s) in RCA: 208] [Impact Index Per Article: 23.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2015] [Revised: 06/08/2015] [Accepted: 06/09/2015] [Indexed: 11/17/2022]
Abstract
Hindered phenols find a wide variety of applications across many different industry sectors. Butylated hydroxytoluene (BHT) is a most commonly used antioxidant recognized as safe for use in foods containing fats, pharmaceuticals, petroleum products, rubber and oil industries. In the past two decades, there has been growing interest in finding novel antioxidants to meet the requirements of these industries. To accelerate the antioxidant discovery process, researchers have designed and synthesized a series of BHT derivatives targeting to improve its antioxidant properties to be having a wide range of antioxidant activities markedly enhanced radical scavenging ability and other physical properties. Accordingly, some structure-activity relationships and rational design strategies for antioxidants based on BHT structure have been suggested and applied in practice. We have identified 14 very sensitive parameters, which may play a major role on the antioxidant performance of BHT. In this review, we attempt to summarize the current knowledge on this topic, which is of significance in selecting and designing novel antioxidants using a well-known antioxidant BHT as a building-block molecule. Our strategy involved investigation on understanding the chemistry behind the antioxidant activities of BHT, whether through hydrogen or electron transfer mechanism to enable promising anti-oxidant candidates to be synthesized.
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Affiliation(s)
- Wageeh A Yehye
- Nanotechnology & Catalysis Research Centre, (NANOCAT), University of Malaya, Block 3A, Institute of Postgraduate Studies Building, 50603 Kuala Lumpur, Malaysia.
| | - Noorsaadah Abdul Rahman
- Department of Chemistry, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Azhar Ariffin
- Department of Chemistry, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Sharifah Bee Abd Hamid
- Nanotechnology & Catalysis Research Centre, (NANOCAT), University of Malaya, Block 3A, Institute of Postgraduate Studies Building, 50603 Kuala Lumpur, Malaysia
| | - Abeer A Alhadi
- Department of Chemistry, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Farkaad A Kadir
- Division of Human Biology, Faculty of Medicine, International Medical University, 57000 Kuala Lumpur, Malaysia
| | - Marzieh Yaeghoobi
- Drug Design and Development Research Group, Department of Chemistry, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia
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Ibrahim SA, Rahman NA, Abu Bakar MH, Girei SH, Yaacob MH, Ahmad H, Mahdi MA. Room temperature ammonia sensing using tapered multimode fiber coated with polyaniline nanofibers. Opt Express 2015; 23:2837-2845. [PMID: 25836144 DOI: 10.1364/oe.23.002837] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We demonstrate an ammonia sensor composed of a tapered multimode fiber coated with polyaniline nanofibers that operates at room temperature (26°C). The optical properties of the polyaniline layer changes when it is exposed to ammonia, leading to a change in the absorption of evanescent field. The fiber sensor was tested by exposing it to ammonia at different concentrations and the absorbance is measured using a spectrophotometer system. Measured response and recovery times are about 2.27 minutes and 9.73 minutes, respectively. The sensor sensitivity can be controlled by adjusting the tapered fiber diameter and the highest sensitivity is achieved when the diameter is reduced to 20 µm.
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Ariffin A, Rahman NA, Yehye WA, Alhadi AA, Kadir FA. PASS-assisted design, synthesis and antioxidant evaluation of new butylated hydroxytoluene derivatives. Eur J Med Chem 2014; 87:564-77. [DOI: 10.1016/j.ejmech.2014.10.001] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2014] [Revised: 09/02/2014] [Accepted: 10/01/2014] [Indexed: 01/22/2023]
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Khan N, Rahman NA, Uddin MS. Choroidal osteoma - case reports. Mymensingh Med J 2014; 23:599-602. [PMID: 25178620] [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: 06/03/2023]
Abstract
Choroidal osteoma is a rare disease. In this article four case histories were described. All were female and young patient. One patient had bilateral and other three had unilateral involvement. They had no family history. One patient reported at eye department in Bangabandhu Sheikh Mujib Medical University (BSMMU) and the other three patients reported in Bangladesh Eye Hospital. Choroidal osteoma is a benign tumor. It is diagnosed by fundoscopy, ocular B-scan ultrasonography, x-ray orbit, FFA, OCT and CT-scan of orbit. Most patients do not require treatment. Hemorrhage on the lesion suggests the presence of sub-retinal neovascularization which are typically treated with laser or intra-vitreal anti-VEGF.
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Affiliation(s)
- N Khan
- Dr Nazneen Khan, Assistant Professor, Department of Ophthalmology, Bangabandhu Sheikh Mujib Medical University (BSMMU), Shahbagh, Dhaka, Bangladesh
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21
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Rothan HA, Zulqarnain M, Ammar YA, Tan EC, Rahman NA, Yusof R. Screening of antiviral activities in medicinal plants extracts against dengue virus using dengue NS2B-NS3 protease assay. Trop Biomed 2014; 31:286-296. [PMID: 25134897] [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: 06/03/2023]
Abstract
Dengue virus infects millions of people worldwide and there is no vaccine or anti-dengue therapeutic available. Screening large numbers of medicinal plants for anti-dengue activities is an alternative strategy in order to find the potent therapeutic compounds. Therefore, this study was designed to identify anti-dengue activities in nineteen medicinal plant extracts that are used in traditional medicine. Local medicinal plants Vernonia cinerea, Hemigraphis reptans, Hedyotis auricularia, Laurentia longiflora, Tridax procumbers and Senna angustifolia were used in this study. The highest inhibitory activates against dengue NS2B-NS3pro was observed in ethanolic extract of S. angustifolia leaves, methanolic extract of V. cinerea leaves and ethanol extract of T. procumbens stems. These findings were further verified by in vitro viral inhibition assay. Methanolic extract of V. cinerea leaves, ethanol extract of T. procumbens stems and at less extent ethanolic extract of S. angustifolia leaves were able to maintain the normal morphology of DENV2-infected Vero cells without causing much cytopathic effects (CPE). The percentage of viral inhibition of V. cinerea and T. procumbens extracts were significantly higher than S. angustifolia extract as measured by plaque formation assay and RT-qPCR. In conclusion, The outcome of this study showed that the methanolic extract of V. cinerea leaves and ethanol extract of T. procumbens stems possessed high inhibitory activates against dengue virus that worth more investigation.
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Affiliation(s)
- H A Rothan
- Department of Molecular Medicine, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - M Zulqarnain
- Department of Genetics, Institute of Biological Science, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Y A Ammar
- Department of Molecular Medicine, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - E C Tan
- Department of Molecular Medicine, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - N A Rahman
- Department of Chemistry, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - R Yusof
- Department of Molecular Medicine, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
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Baharuddin A, Amir Hassan A, Othman R, Xu Y, Huang M, Ario Tejo B, Yusof R, Abdul Rahman N, Othman S. Dengue Envelope Domain III-Peptide Binding Analysis via Tryptophan Fluorescence Quenching Assay. Chem Pharm Bull (Tokyo) 2014; 62:947-55. [DOI: 10.1248/cpb.c14-00165] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Aida Baharuddin
- Drug Design and Development Research Group, University of Malaya
- Department of Molecular Medicine, Faculty of Medicine, University of Malaya
| | - Asfarina Amir Hassan
- Drug Design and Development Research Group, University of Malaya
- Department of Pharmacy, Faculty of Medicine, University of Malaya
| | - Rozana Othman
- Drug Design and Development Research Group, University of Malaya
- Department of Pharmacy, Faculty of Medicine, University of Malaya
- Centre for Natural Product and Drug Discovery, University of Malaya
| | - Yongtao Xu
- School of Chemistry and Chemical Engineering, Queen’s University Belfast
| | - Meilan Huang
- School of Chemistry and Chemical Engineering, Queen’s University Belfast
| | - Bimo Ario Tejo
- Center for Infectious Diseases Research, Surya University
| | - Rohana Yusof
- Drug Design and Development Research Group, University of Malaya
- Department of Molecular Medicine, Faculty of Medicine, University of Malaya
| | | | - Shatrah Othman
- Drug Design and Development Research Group, University of Malaya
- Department of Molecular Medicine, Faculty of Medicine, University of Malaya
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Md Daud MK, Mohamadl H, Haron A, Rahman NA. Ototoxicity screening of patients treated with streptomycin using distortion product otoacoustic emissions. B-ENT 2014; 10:53-58. [PMID: 24765829] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023] Open
Abstract
OBJECTIVE Pure tone audiometry (PTA) is currently widely used to monitor ototoxicity, but this method is time-consuming. Here we validate distortion product otoacoustic emission (DPOAE) as an instrument for early detection of ototoxicity. METHODS A cohort study was performed on newly diagnosed tuberculosis patients who were treated with streptomycin. The patients underwent hearing assessment using conventional PTA and high-frequency DPOAE (8, 9 and 10 kHz) on days 0, 7, 14, 28 and 56 of streptomycin treatment. Detection of ototoxicity according to the duration of streptomycin treatment was compared between DPOAE and PTA. RESULTS Of 96 newly diagnosed patients treated with streptomycin, 50 completed the study. During the treatment period, 62.5% of the patients had vertigo, while 37.5% complained of tinnitus. DPOAE detected ototoxicity in 47.7% of the cases at day 7, 66.0% at day 14, 70.0% at day 28 and 77.1% at day 56 of streptomycin treatment. The higher frequencies were affected more by ototoxicity, with significant differences at 8 vs. 9 kHz on all testing days and at 9 vs. 10 kHz except on days 7 and 56 (p < 0.001). Hearing loss was detected by PTA in 2.3% of patients on day 7, in 10.6% on day 14, in 22.0% on day 48 and in 29.2% on day 56. CONCLUSION DPOAE is a sensitive tool that can detect early changes in the cochlea due to ototoxicity. Use of DPOAE rather than PTA to screen for ototoxicity could reduce screening time and would allow clinical monitoring of more patients.
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Pyle JA, Warwick NJ, Harris NRP, Abas MR, Archibald AT, Ashfold MJ, Ashworth K, Barkley MP, Carver GD, Chance K, Dorsey JR, Fowler D, Gonzi S, Gostlow B, Hewitt CN, Kurosu TP, Lee JD, Langford SB, Mills G, Moller S, MacKenzie AR, Manning AJ, Misztal P, Nadzir MSM, Nemitz E, Newton HM, O'Brien LM, Ong S, Oram D, Palmer PI, Peng LK, Phang SM, Pike R, Pugh TAM, Rahman NA, Robinson AD, Sentian J, Samah AA, Skiba U, Ung HE, Yong SE, Young PJ. The impact of local surface changes in Borneo on atmospheric composition at wider spatial scales: coastal processes, land-use change and air quality. Philos Trans R Soc Lond B Biol Sci 2012; 366:3210-24. [PMID: 22006963 DOI: 10.1098/rstb.2011.0060] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
We present results from the OP3 campaign in Sabah during 2008 that allow us to study the impact of local emission changes over Borneo on atmospheric composition at the regional and wider scale. OP3 constituent data provide an important constraint on model performance. Treatment of boundary layer processes is highlighted as an important area of model uncertainty. Model studies of land-use change confirm earlier work, indicating that further changes to intensive oil palm agriculture in South East Asia, and the tropics in general, could have important impacts on air quality, with the biggest factor being the concomitant changes in NO(x) emissions. With the model scenarios used here, local increases in ozone of around 50 per cent could occur. We also report measurements of short-lived brominated compounds around Sabah suggesting that oceanic (and, especially, coastal) emission sources dominate locally. The concentration of bromine in short-lived halocarbons measured at the surface during OP3 amounted to about 7 ppt, setting an upper limit on the amount of these species that can reach the lower stratosphere.
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Affiliation(s)
- J A Pyle
- National Centre for Atmospheric Science, NCAS, UK.
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Yehye WA, Ariffin A, Rahman NA, Ng SW. 2-[4-Acetyl-5-(biphenyl-4-yl)-4,5-dihydro-1,3,4-oxadiazol-2-yl]phenyl acetate. Acta Crystallogr Sect E Struct Rep Online 2010; 66:o878. [PMID: 21580697 PMCID: PMC2984012 DOI: 10.1107/s1600536810009621] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [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: 03/11/2010] [Accepted: 03/14/2010] [Indexed: 11/22/2022]
Abstract
In the title molecule, C24H20N2O4, the five-membered oxadiazole ring is nearly planar (r.m.s. deviation = 0.053 Å) and the phenyl ring of the biphenyl unit attached to it forms a dihedral angle of 73.2 (1)°; the other phenyl ring is close to coplanar with the oxadiazole ring [dihedral angle = 6.2 (2)°].
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Affiliation(s)
- Wagee A Yehye
- Department of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
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Yehye WA, Ariffin A, Rahman NA, Ng SW. N'-[(Biphenyl-4-yl)methyl-ene]-2-[(3,5-di-tert-butyl-4-hydroxy-benz-yl)sulfan-yl]acetohydrazide. Acta Crystallogr Sect E Struct Rep Online 2010; 66:o734. [PMID: 21580580 PMCID: PMC2983883 DOI: 10.1107/s1600536810006884] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2010] [Accepted: 02/23/2010] [Indexed: 05/30/2023]
Abstract
In the title compound, C(30)H(36)N(2)O(2)S, the dihedral angle between the two aromatic rings of the biphenyl residue is 31.2 (1)°. The two methyl-ene C atoms subtend an angle of 99.9 (1)° at the S atom. In the crystal, mol-ecules form inversion dimers linked by pairs of N-H⋯O hydrogen bonds. The hydroxyl group is shielded by the tert-butyl residues and is therefore not involved in any hydrogen bonding.
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Affiliation(s)
- Wagee A. Yehye
- Department of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Azhar Ariffin
- Department of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | | | - Seik Weng Ng
- Department of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
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Loghmani-Khouzani H, Abdul Rahman N, Robinson WT, Yaeghoobi M, Kia R. (E)-3-(6-Nitro-benzo[d][1,3]dioxol-5-yl)-1-(2,4,6-trimethoxy-phen-yl)prop-2-en-1-one. Acta Crystallogr Sect E Struct Rep Online 2009; 65:o2545. [PMID: 21577987 PMCID: PMC2970272 DOI: 10.1107/s1600536809036435] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2009] [Accepted: 09/09/2009] [Indexed: 11/21/2022]
Abstract
In the molecule of the title compound, C19H17NO8, the benzodioxole unit is oriented at a dihedral angle of 61.45 (6)° with respect to the methoxy-substituted phenyl ring. The nitro group is not co-planar to the benzene ring to which it is attached, making a dihedral angle of 31.86 (17)°. In the crystal structure, intermolecular C—H⋯O interactions link the molecules into chains through R22(8) ring motifs. The π⋯π contacts between the benzodioxole rings, [centroid–centroid distances = 3.7610 (9), 3.6613 (9) and 3.7975 (9) Å] may further stabilize the structure.
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Yehye WA, Ariffin A, Rahman NA, Ng SW. 2-(3,5-Di- tert-butyl-4-hydroxybenzylsulfanyl)- N′-(3-methoxybenzylidene)acetohydrazide. Acta Crystallogr Sect E Struct Rep Online 2009; 65:o2112. [PMID: 21577527 PMCID: PMC2970103 DOI: 10.1107/s1600536809030645] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2009] [Accepted: 08/01/2009] [Indexed: 11/10/2022]
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Loghmani-Khouzani H, Hajiheidari D, Robinson WT, Abdul Rahman N, Kia R. 2-(1,3-Benzothia-zol-2-ylsulfan-yl)-1-phenyl-ethanone. Acta Crystallogr Sect E Struct Rep Online 2009; 65:o2441. [PMID: 21577896 PMCID: PMC2970398 DOI: 10.1107/s1600536809033121] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2009] [Accepted: 08/19/2009] [Indexed: 11/11/2022]
Abstract
In the mol-ecule of the title compound, C(15)H(11)NOS(2), the 1,3-benzothia-zole ring is oriented at a dihedral angle of 6.61 (6)° with respect to the phenyl ring. In the crystal structure, inter-molecular C-H⋯O inter-actions link the mol-ecules in a herring-bone arrangement along the b axis and π-π contacts between the thia-zole and phenyl rings [centroid-centroid distance = 3.851 (1) Å] may further stabilize the structure.
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Loghmani-Khouzani H, Hajiheidari D, Robinson WT, Abdul Rahman N, Kia R. 2-(1,3-Benzoxazol-2-ylsulfan-yl)-1-phenyl-ethanone. Acta Crystallogr Sect E Struct Rep Online 2009; 65:o2287. [PMID: 21577679 PMCID: PMC2970099 DOI: 10.1107/s1600536809033960] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2009] [Accepted: 08/25/2009] [Indexed: 11/10/2022]
Abstract
In the title compound, C(15)H(11)NO(2)S, a new thio-benzoxazole derivative, the dihedral angle between the benzoxazole ring and the phenyl ring is 9.91 (9)°. An inter-esting feature of the crystal structure is the short C⋯S [3.4858 (17) Å] contact, which is shorter than the sum of the van der Waals radii of these atoms. In the crystal structure, mol-ecules are linked together by zigzag inter-molecular C-H⋯N inter-actions into a column along the a axis. The crystal structure is further stabilized by inter-molecular π-π inter-actions [centroid-centroid = 3.8048 (10) Å].
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Yaeghoobi M, Rahman NA, Ng SW. 4-Chloro-2-[( E)-2-(4-methoxyphenyl)ethyliminomethyl]phenol. Acta Crystallogr Sect E Struct Rep Online 2009; 65:o1070. [PMID: 21583886 PMCID: PMC2977750 DOI: 10.1107/s1600536809013348] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2009] [Accepted: 04/08/2009] [Indexed: 11/11/2022]
Abstract
In the title Schiff base, C16H16ClNO2, the 2-(4-methoxyphenyl)ethyl (CH3OC6H4CH2CH2–; r.m.s. deviation = 0.10 Å) and 4-chloro-2-(iminomethyl)phenol (N=CHC6H3ClOH; r.m.s. deviation = 0.01 Å) portions are both essentially planar, the two parts being inclined at an angle of 61.8 (1)°. The hydroxy group forms a hydrogen bond to the imino N atom.
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Abstract
The dianion of the title salt, 2C5H6N+·C12H6N2O4S22−, lies on a special position of 2 site symmetry that relates one thionicotinate part to the other, and the dihedral angle between the niotinate planes is 89.2 (2)°. The pyridinium cations are hydrogen bonded to the carboxylate group by way of N—H⋯O links.
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Affiliation(s)
- Wagee A Yehye
- Department of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
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Rahman NA, Das S, Maatoq Sulaiman I, Hlaing KPP, Haji Suhaimi F, Latiff AA, Othman F. The sternalis muscle in cadavers: anatomical facts and clinical significance. Clin Ter 2009; 160:129-131. [PMID: 19452102] [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: 05/27/2023]
Abstract
The sternalis is an anomalous muscle located in the anterior wall of thorax and several past reports have described its presence with clinical implications. The sternalis muscle may be incidentally detected during routine cadaveric dissections and autopsies. We observed the presence of anomalous sternalis muscle on both sides of the anterior chest wall in 25 cadavers (n = 50), over a span of three years. Out of a 50 cases, we observed a single case of sternalis on the right side of the 55-year-old male cadaver (2%). The sternalis was found to be absent in the rest 49 cases (98%). The sternalis muscle displayed an oblique course in the anterior wall of the thorax. The muscle originated near the seventh costal cartilage extending obliquely upwards to insert into the second costal cartilage close to the sternum. The originating portion of the muscle was located at a distance of 3.5 cm lateral to the mid-sternal plane. The vertical length and the maximum width of the anomalous sternalis muscle measured 9 cm and 1.9 cm, respectively. The fibers of the muscle vertically ascended upwards. No other associated anomalies were observed in the same cadaver. The presence of sternalis muscle is considered to be a rare variation with no earlier studies being performed in the Malaysian population. The anomalous sternalis muscle may be important for reconstructive surgeons performing mastectomy and radiologists interpreting mammograms. Thus, the sternalis muscle may be academically, anthropologically and surgically important.
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Affiliation(s)
- N A Rahman
- Department of Anatomy, Universiti Kebangsaan Malaysia, 50300 Kuala Lumpur, Malaysia
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Chee CF, Rahman NA, Zain SM, Ng SW. Pheophorbide b ethyl ester from a chlorella vulgaris dietary supplement. Acta Crystallogr Sect E Struct Rep Online 2008; 64:o1986. [PMID: 21201185 PMCID: PMC2959371 DOI: 10.1107/s160053680802970x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [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: 09/10/2008] [Accepted: 09/16/2008] [Indexed: 11/10/2022]
Abstract
In the title compound, C37H38N4O6, four five-membered nitrogen-bearing rings are nearly coplanar. Two N atoms in two these five-membered rings have attached H atoms, which contribute to the formation of intramolecular N—H⋯N hydrogen bonds [N⋯N = 2.713 (5)–3.033 (6) Å].
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Affiliation(s)
- Chin Fei Chee
- Department of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
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35
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Mansor S, Yehye WA, Ariffin A, Rahman NA, Ng SW. Di- n-butylammonium 2-(3,5-di- tert-butyl-4-hydroxybenzylsulfanyl)nicotinate. Acta Crystallogr Sect E Struct Rep Online 2008; 64:o1799. [PMID: 21201778 PMCID: PMC2960651 DOI: 10.1107/s1600536808026202] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2008] [Accepted: 08/13/2008] [Indexed: 05/26/2023]
Abstract
The asymmetric unit of the title compound, C8H20N+·C21H26NO3S−, contains two indpendent ion pairs which are disposed about a psuedo-inversion center, generating an ammonium–carboxylate N—H⋯O hydrogen-bonded four-component cluster. In the crystal structure, adjacent clusters are linked by hydroxy–carboxylate O—H⋯O hydrogen bonds, forming a chain.
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Yehye WA, Rahman NA, Ariffin A, Ng SW. N-Acetyl-2-hydroxy-N'-[methoxy(1-methylindol-2-yl)methyl]benzohydrazide. Acta Crystallogr Sect E Struct Rep Online 2008; 64:o1824. [PMID: 21201799 PMCID: PMC2960481 DOI: 10.1107/s1600536808026846] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [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: 08/19/2008] [Accepted: 08/20/2008] [Indexed: 11/11/2022]
Abstract
In the crystal structure of the title Schiff-base, C(20)H(21)N(3)O(4), the amino group forms an N-H⋯O hydrogen bond to the acetyl group of an adjacent mol-ecule, forming a zigzag chain. The 2-hydr-oxy group is inter-nally hydrogen bonded to the amido group though an O-H⋯O hydrogen bond.
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Affiliation(s)
- Wagee A. Yehye
- Department of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | | | - Azhar Ariffin
- Department of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Seik Weng Ng
- Department of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
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Mansor S, Yehye WA, Ariffin A, Rahman NA, Ng SW. 2-(3,5-Di-tert-butyl-4-hydroxy-benzyl-sulfan-yl)nicotinic acid. Acta Crystallogr Sect E Struct Rep Online 2008; 64:o1778. [PMID: 21201758 PMCID: PMC2960523 DOI: 10.1107/s1600536808026056] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [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: 08/11/2008] [Accepted: 08/13/2008] [Indexed: 11/26/2022]
Abstract
Two molecules of the title compound, C21H27NO3S, are disposed about a center of inversion, generating an O—H⋯O hydrogen-bonded dimer.
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Affiliation(s)
- Shahirah Mansor
- Department of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
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Othman R, Kiat TS, Khalid N, Yusof R, Irene Newhouse E, Newhouse JS, Alam M, Rahman NA. Docking of Noncompetitive Inhibitors into Dengue Virus Type 2 Protease: Understanding the Interactions with Allosteric Binding Sites. J Chem Inf Model 2008; 48:1582-91. [DOI: 10.1021/ci700388k] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Rozana Othman
- Pharmacy Department and Department of Molecular Medicine, Faculty of Medicine and Institute of Biological Sciences and Chemistry Department, Faculty of Science, Universiti Malaya, 50603 Kuala Lumpur, Malaysia, Sunway University College, Bandar Sunway, 46150 Petaling Jaya, Malaysia, Advanced Studies in Genomics, Proteomics and Bioinformatics, University of Hawaii at Manoa, 2565 McCarthy Mall, Keller 319, Honolulu, Hawaii 96822, Maui High Performance Computing Center, 550 Lipoa Parkway, Kihei, Hawaii 96753
| | - Tan Siew Kiat
- Pharmacy Department and Department of Molecular Medicine, Faculty of Medicine and Institute of Biological Sciences and Chemistry Department, Faculty of Science, Universiti Malaya, 50603 Kuala Lumpur, Malaysia, Sunway University College, Bandar Sunway, 46150 Petaling Jaya, Malaysia, Advanced Studies in Genomics, Proteomics and Bioinformatics, University of Hawaii at Manoa, 2565 McCarthy Mall, Keller 319, Honolulu, Hawaii 96822, Maui High Performance Computing Center, 550 Lipoa Parkway, Kihei, Hawaii 96753
| | - Norzulaani Khalid
- Pharmacy Department and Department of Molecular Medicine, Faculty of Medicine and Institute of Biological Sciences and Chemistry Department, Faculty of Science, Universiti Malaya, 50603 Kuala Lumpur, Malaysia, Sunway University College, Bandar Sunway, 46150 Petaling Jaya, Malaysia, Advanced Studies in Genomics, Proteomics and Bioinformatics, University of Hawaii at Manoa, 2565 McCarthy Mall, Keller 319, Honolulu, Hawaii 96822, Maui High Performance Computing Center, 550 Lipoa Parkway, Kihei, Hawaii 96753
| | - Rohana Yusof
- Pharmacy Department and Department of Molecular Medicine, Faculty of Medicine and Institute of Biological Sciences and Chemistry Department, Faculty of Science, Universiti Malaya, 50603 Kuala Lumpur, Malaysia, Sunway University College, Bandar Sunway, 46150 Petaling Jaya, Malaysia, Advanced Studies in Genomics, Proteomics and Bioinformatics, University of Hawaii at Manoa, 2565 McCarthy Mall, Keller 319, Honolulu, Hawaii 96822, Maui High Performance Computing Center, 550 Lipoa Parkway, Kihei, Hawaii 96753
| | - E. Irene Newhouse
- Pharmacy Department and Department of Molecular Medicine, Faculty of Medicine and Institute of Biological Sciences and Chemistry Department, Faculty of Science, Universiti Malaya, 50603 Kuala Lumpur, Malaysia, Sunway University College, Bandar Sunway, 46150 Petaling Jaya, Malaysia, Advanced Studies in Genomics, Proteomics and Bioinformatics, University of Hawaii at Manoa, 2565 McCarthy Mall, Keller 319, Honolulu, Hawaii 96822, Maui High Performance Computing Center, 550 Lipoa Parkway, Kihei, Hawaii 96753
| | - James S. Newhouse
- Pharmacy Department and Department of Molecular Medicine, Faculty of Medicine and Institute of Biological Sciences and Chemistry Department, Faculty of Science, Universiti Malaya, 50603 Kuala Lumpur, Malaysia, Sunway University College, Bandar Sunway, 46150 Petaling Jaya, Malaysia, Advanced Studies in Genomics, Proteomics and Bioinformatics, University of Hawaii at Manoa, 2565 McCarthy Mall, Keller 319, Honolulu, Hawaii 96822, Maui High Performance Computing Center, 550 Lipoa Parkway, Kihei, Hawaii 96753
| | - Masqudul Alam
- Pharmacy Department and Department of Molecular Medicine, Faculty of Medicine and Institute of Biological Sciences and Chemistry Department, Faculty of Science, Universiti Malaya, 50603 Kuala Lumpur, Malaysia, Sunway University College, Bandar Sunway, 46150 Petaling Jaya, Malaysia, Advanced Studies in Genomics, Proteomics and Bioinformatics, University of Hawaii at Manoa, 2565 McCarthy Mall, Keller 319, Honolulu, Hawaii 96822, Maui High Performance Computing Center, 550 Lipoa Parkway, Kihei, Hawaii 96753
| | - Noorsaadah Abdul Rahman
- Pharmacy Department and Department of Molecular Medicine, Faculty of Medicine and Institute of Biological Sciences and Chemistry Department, Faculty of Science, Universiti Malaya, 50603 Kuala Lumpur, Malaysia, Sunway University College, Bandar Sunway, 46150 Petaling Jaya, Malaysia, Advanced Studies in Genomics, Proteomics and Bioinformatics, University of Hawaii at Manoa, 2565 McCarthy Mall, Keller 319, Honolulu, Hawaii 96822, Maui High Performance Computing Center, 550 Lipoa Parkway, Kihei, Hawaii 96753
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Hussaini HM, Rahman NA, Rahman RA, Nor GM, Ai Idrus SM, Ramli R. Maxillofacial trauma with emphasis on soft-tissue injuries in Malaysia. Int J Oral Maxillofac Surg 2007; 36:797-801. [PMID: 17630250 DOI: 10.1016/j.ijom.2007.04.004] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2005] [Revised: 12/08/2006] [Accepted: 04/09/2007] [Indexed: 10/23/2022]
Abstract
Soft-tissue injuries with or without facial bone involvement are the most common presentation following maxillofacial trauma. The objective of this study was to look at the distribution, pattern and type of soft-tissue injury in relation to aetiology. Records of patients over a period of 5 years (1998-2002), who sustained maxillofacial injuries and were treated at Kajang Hospital, a secondary referral hospital, were reviewed. Out of 313 patients with maxillofacial injuries, 295 patients sustained soft-tissue injuries. Males (79%) between 21 and 30 years old (34%) were the majority of patients. Road-traffic accident was the main cause of soft-tissue injuries (75%) with motorcycle accident being the most frequent (40%). The upper lips (23%) and the lower lips (18%) were the most common extraoral site involved, while the labial mucosa and sulcular areas, both accounting for 21%, were the most common intraoral sites. Stringent road-traffic regulations should be practiced in developing countries, as morbidity arising from road-traffic accidents poses a national economic and social problem.
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Affiliation(s)
- H M Hussaini
- Department of Oral Pathology & Oral Medicine, Faculty of Dentistry, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia
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Rivero-Müller A, Vuorenoja S, Tuominen M, Wacławik A, Brokken LJS, Ziecik AJ, Huhtaniemi I, Rahman NA. Use of hecate-chorionic gonadotropin beta conjugate in therapy of lutenizing hormone receptor expressing gonadal somatic cell tumors. Mol Cell Endocrinol 2007; 269:17-25. [PMID: 17363137 DOI: 10.1016/j.mce.2006.11.016] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/14/2006] [Revised: 11/28/2006] [Accepted: 11/28/2006] [Indexed: 01/19/2023]
Abstract
Improvement of cancer treatment is a major challenge of medical research. Despite the immense efforts made in the improvement of diagnosis and treatment, cancer remains a major concern and cause of morbidity and mortality. Most of the modern anti-neoplastic therapies have severe side effects, and tumor cells often develop drug resistance. There is promise in the new generation of treatments (gene therapy, immunotherapy, vaccines, etc.) that are under development, but the efficacies and side effects of such therapies have so far been disappointing. Receptor-based therapies are not new, but many normal cells also present the same receptors reducing the specificity of such approaches. Several lytic peptides have been investigated because of they appear to kill cancer cells due to changes of their membrane potential. Thus, linking receptor-specific ligands to lytic peptides is expected to augment the specificity of targeting and decrease the toxicity of lytic peptides on normal cells. One such polypeptide is hecate (an analogue to the bee venom main component, melittin) that preferentially kills cancer cells at low doses. When this peptide is fused with the 81-95 amino acid fragment of chorionic gonadotropin-beta (CGbeta) subunit (hecate-CGbeta), it targets cells expressing luteinizing hormone receptor (LHR), even at very low doses, or when LHR is expressed at low level. Our recent data showed that this peptide conjugate is efficient in destroying LHR-positive cells in xenografts and more importantly in transgenic mouse models developing LHR-positive somatic cell tumors in gonads. The mechanism of action of hecate-CGbeta after binding to LHR is destruction of cell membranes resulting in rapid cell death by necrosis with minimal side effects. This review summarizes our findings on the action of this novel peptide and considers the future potential of this family of targeting peptides in the treatment of neoplasias.
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Affiliation(s)
- A Rivero-Müller
- Department of Physiology, University of Turku, Kiinamyllynkatu 10, FIN-20520 Turku, Finland
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Chia SL, Tan WS, Shaari K, Abdul Rahman N, Yusoff K, Satyanarayanajois SD. Structural analysis of peptides that interact with Newcastle disease virus. Peptides 2006; 27:1217-25. [PMID: 16377031 DOI: 10.1016/j.peptides.2005.11.018] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [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] [Received: 09/02/2005] [Revised: 11/11/2005] [Accepted: 11/11/2005] [Indexed: 12/28/2022]
Abstract
A peptide with the sequence CTLTTKLYC has previously been identified to inhibit the propagation of Newcastle disease virus (NDV) in embryonated chicken eggs and tissue culture. NDV has been classified into two main groups: the velogenic group, and mesogenic with lentogenic strains as the other group based on its dissociation constants. In this study the peptide, CTLTTKLYC, displayed on the pIII protein of a filamentous M13 phage was synthesized and mutated in order to identify the amino acid residues involved in the interactions with NDV. Mutations of C1 and K6 to A1 and A6 did not affect the binding significantly, but substitution of Y8 with A8 dramatically reduced the interaction. This suggests that Y8 plays an important role in the peptide-virus interaction. The three-dimensional structure of the peptide was determined using circular dichroism (CD), nuclear magnetic resonance (NMR), and molecular modeling. The peptide exhibited two possible conformers. One that consists of consecutive beta-turns around T2-L3-T4-T5 and K6-L7-Y8-C9. The other conformer exhibited a beta-hairpin bend type of structure with a bend around L3-T4-T5-K6.
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Affiliation(s)
- Suet Lin Chia
- Department of Microbiology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Malaysia
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Ooi A, Tan S, Mohamed R, Rahman NA, Othman RY. The full-length clone of cucumber green mottle mosaic virus and its application as an expression system for Hepatitis B surface antigen. J Biotechnol 2006; 121:471-81. [PMID: 16271415 DOI: 10.1016/j.jbiotec.2005.08.032] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2005] [Revised: 07/19/2005] [Accepted: 08/24/2005] [Indexed: 11/20/2022]
Abstract
A cucumber green mosaic mottle virus (CGMMV) full-length clone was developed for the expression of Hepatitis B surface antigen (HBsAg). The expression of the surface displayed HBsAg by the chimeric virus was confirmed through a double antibody sandwich ELISA. Assessment of the coat protein composition of the chimeric virus particles by SDS-PAGE analysis showed that 50% of the coat proteins were fused to the HBsAg. Biological activity of the expressed HBsAg was assessed through the stimulation of in vitro antibody production by cultured peripheral blood mononuclear cells (PBMC). PBMC that were cultured in the presence of the chimeric virus showed up to an approximately three-fold increase in the level of anti HBsAg immunoglobulin thus suggesting the possible use of this new chimeric virus as an effective Hepatitis B vaccine.
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Affiliation(s)
- Aikseng Ooi
- Institute of Biological Science, Faculty of Science, University of Malaya, Kuala Lumpur, Malaysia
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43
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Asi AM, Rahman NA, Merican AF. Application of the linear interaction energy method (LIE) to estimate the binding free energy values of Escherichia coli wild-type and mutant arginine repressor C-terminal domain (ArgRc)–l-arginine and ArgRc–l-citrulline protein–ligand complexes. J Mol Graph Model 2004; 22:249-62. [PMID: 15177077 DOI: 10.1016/j.jmgm.2003.09.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2003] [Revised: 08/21/2003] [Accepted: 09/12/2003] [Indexed: 10/26/2022]
Abstract
Protein-ligand binding free energy values of wild-type and mutant C-terminal domain of Escherichia coli arginine repressor (ArgRc) protein systems bound to L-arginine or L-citrulline molecules were calculated using the linear interaction energy (LIE) method by molecular dynamics (MD) simulation. The binding behaviour predicted by the dissociation constant (K(d)) calculations from the binding free energy values showed preferences for binding of L-arginine to the wild-type ArgRc but not to the mutant ArgRc(D128N). On the other hand, L-citrulline do not favour binding to wild-type ArgRc but prefer binding to mutant ArgRc(D128N). The dissociation constant for the wild-type ArgRc-L-arginine complex obtained in this study is in agreement with reported experimental results. Our results also support the experimental data for the binding of L-citrulline to the mutant ArgRc(D128N). These showed that LIE method for protein-ligand binding free energy calculation could be applied to the wild-type and the mutant E. coli ArgRc-L-arginine and ArgRc-L-citrulline protein-ligand complexes and possibly to other transcriptional repressor-co-repressor systems as well.
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Affiliation(s)
- A M Asi
- Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia
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Abstract
Phase separation of binary blends of various combinations of poly (L-lactide) (PLA), and poly (D,L-lactide-co-glycolide) (PLGA), was investigated using differential scanning calorimetry (DSC). Based on this phase separation phenomenon, double-walled microspheres were fabricated. A model agent, bovine serum albumin (BSA) labeled with fluorescein isothiocyanate (FITC-BSA) was localized in each layer. Scanning electron microscopy (SEM) and fluorescence microscopy (FM) were used to assess the formation of double-walled microspheres and the localization of the drug, respectively. When a 1:1 polymer ratio was used, the FITC-BSA was localized in the outer layer. When the relative ratio of PLGA to PLA was increased to 3:1 using the same overall polymer concentration, the FITC-BSA was localized in the inner core. Release studies were carried out to evaluate the advantage of double-walled microspheres compared to single walled microspheres. Microspheres made with FITC-BSA localized in the inner core exhibited a significantly lower initial release rate compared to microspheres where the drug was located in the outer layer, or compared to microspheres made from PLA only. Hence microspheres with a double-walled morphology have the potential for therapeutic use where a high burst might be detrimental.
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Affiliation(s)
- N A Rahman
- Department of Molecular Pharmacology, Physiology and Biotechnology, Brown University, Box G, Providence, RI 02912, USA
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Kueh R, Rahman NA, Merican AF. Computational docking of L-arginine and its structural analogues to C-terminal domain of Escherichia coli arginine repressor protein (ArgRc). J Mol Model 2003; 9:88-98. [PMID: 12707802 DOI: 10.1007/s00894-002-0115-8] [Citation(s) in RCA: 4] [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] [Received: 07/12/2002] [Accepted: 11/20/2002] [Indexed: 10/21/2022]
Abstract
The arginine repressor (ArgR) of Escherichia coli binds to six L-arginine molecules that act as its co-repressor in order to bind to DNA. The binding of L-arginine molecules as well as its structural analogues is compared by means of computational docking. A grid-based energy evaluation method combined with a Monte Carlo simulated annealing process was used in the automated docking. For all ligands, the docking procedure proposed more than one binding site in the C-terminal domain of ArgR (ArgRc). Interaction patterns of ArgRc with L-arginine were also observed for L-canavanine and L-citrulline. L-lysine and L-homoarginine, on the other hand, were shown to bind poorly at the binding site. Figure A general overview of the sites found from docking the various ligands into ArgRc ( grey ribbons). Red coloured sticks: residues in binding site H that was selected for docking
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Affiliation(s)
- Rowyna Kueh
- Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603, Kuala Lumpur, Malaysia
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Rahman NA, Kiiveri S, Siltanen S, Levallet J, Kero J, Lensu T, Wilson DB, Heikinheimo MT, Huhtaniemi IT. Adrenocortical tumorigenesis in transgenic mice: the role of luteinizing hormone receptor and transcription factors GATA-4 and GATA-61. Reprod Biol 2001; 1:5-9. [PMID: 14666170] [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: 04/27/2023]
Abstract
Transgenic (TG) mice, bearing the Simian Virus 40 T-antigen (Tag) under a 6-kb fragment of the murine inhibin alpha-subunit promoter (inhalpha), develop gonadal tumors of granulosa or Leydig cell origin with 100% penetrance by the age of 5-7 months. When these TG mice were gonadectomized prepubertally, between 21-25 days of life, adrenal gland tumors were observed in each mouse by the age of 5-7 months. No adrenal tumors were detected in any intact TG, gonadectomized or intact or control non-TG littermates. The adrenocortical tumors appeared to originate from the X-zone of the adrenal cortex. If functional gonadectomy was induced by GnRH antagonist treatment or by cross-breeding of the TG mice into hypogonadotropic hpg genetic background, neither gonadal nor adrenal tumorigenesis appeared. This prompted a hypothesis that adrenal tumor development in inhalpha/Tag TG mice is related to elevated gonadotropin secretion, which is the most obvious difference between the surgical and functional gonadectomy models. The adrenal tumors and a cell line (Calpha1) derived from them, was found to express luteinizing hormone receptor (LHR), but no FSHR, and hCG treatment stimulated their proliferation. No FSHR was found in the adrenal glands. On the basis of this it was suggested that expression of the potent oncogene T-antigen, allow LH in adrenocortical cells to function as a tumor promoter, and induction of high level functional LHR expression in adrenal tumors. Given the induction of expression and regulation of the GATA-4 and GATA-6 zinc finger family of transcription factors in the gonads by gonadotropins, it was in our interest to explore their expression in the adrenals. We utilized the inalpha/Tag TG mouse model and pathological human adrenal samples to explore the role of GATA-4 and GATA-6 in adrenocortical tumorigenesis. Abundant GATA-6 mRNA expression was found in normal control adrenal cortex during mouse development, whereas GATA-4 mRNA was undetectable. In striking contrast to this, GATA-6 was absent from murine adrenocortical tumors, while GATA-4 mRNA expression was dramatically upregulated in the murine adrenal tumors as well as in human adrenocortical carcinomas. Taken together, these results suggest different roles for GATA-4 and GATA-6 in the adrenal gland, and implicate GATA-4 in adrenal LHR expression and tumorigenesis. Immunohistochemical detection of GATA-4 may serve as a useful marker in differential diagnosis of human adrenal tumors. In addition, the inhalpha/Tag TG model will be helpful for exploring the molecular mechanisms underlying adrenocortical tumorigenesis, ectopic LHR expression in adrenals and the GATA-4/LHR interaction that is related to adrenal tumorigenesis in TG mice.
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Affiliation(s)
- N A Rahman
- Department of Physiology, University of Turku, Kiinamyllynkatu 10, FIN-20520 Turku, Finland.
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Mikola MK, Rahman NA, Paukku TH, Ahtiainen PM, Vaskivuo TE, Tapanainen JS, Poutanen M, Huhtaniemi IT. Gonadal tumors of mice double transgenic for inhibin-alpha promoter-driven simian virus 40 T-antigen and herpes simplex virus thymidine kinase are sensitive to ganciclovir treatment. J Endocrinol 2001; 170:79-90. [PMID: 11431140 DOI: 10.1677/joe.0.1700079] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [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: 11/27/2022]
Abstract
We have previously produced transgenic (TG) mice expressing the mouse inhibin alpha-subunit promoter/Simian virus 40 T-antigen (Inhalpha/Tag) fusion gene. The mice develop gonadal somatic cell tumors at the age of 5-7 months; the ovarian tumors originate from granulosa cells, and those of the testes from Leydig cells. In the present study another TG mouse line was produced, expressing under the same inh-alpha promoter the herpes simplex virus thymidine kinase gene (Inhalpha/TK). Crossbreeding of the two TG mouse lines resulted in double TG mice (Inhalpha/TK-Inhalpha/Tag), which also developed gonadal tumors. The single (Inhalpha/Tag) and double TG (Inhalpha/TK-Inhalpha/Tag) mice, both bearing gonadal tumors, were treated at the age of 5.5-6.5 months with ganciclovir (GCV, 150 mg/kg body weight twice daily i.p.) for 14 days, or with aciclovir (ACV, 300-400 mg/kg body weight per day perorally) for 2 months. During GCV treatment, the total gonadal volume including the tumor, decreased in double TG mice by an average of 40% (P<0.05), while in single TG mice, there was a concomitant increase of 60% in gonadal size (P<0.05). GCV was also found to increase apoptosis in gonads of the double TG mice. Peroral treatment with ACV was less effective, it did not reduce significantly the gonadal volume. We also analyzed the in vitro efficacy of ACV and GCV treatments in transiently HSV-TK-transfected KK-1 murine granulosa tumor cells, originating from a single-positive Inhalpha/Tag mouse. GCV proved to be more effective and more specific than ACV in action. These results prove the principle that targeted expression of the HSV-TK gene in gonadal somatic cell tumors is potentially useful for tumor ablation by antiherpes treatment. The findings provide a lead for further development of somatic gene therapy for gonadal tumors.
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Affiliation(s)
- M K Mikola
- Department of Physiology, University of Turku, Kiinamyllynkatu 10, FIN-20520, Turku, Finland
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Farnworth PG, Harrison CA, Leembruggen P, Chan KL, Stanton PG, Ooi GT, Rahman NA, Huhtaniemi IT, Findlay JK, Robertson DM. Inhibin binding sites and proteins in pituitary, gonadal, adrenal and bone cells. Mol Cell Endocrinol 2001; 180:63-71. [PMID: 11451573 DOI: 10.1016/s0303-7207(01)00499-3] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Activin signals via complexes of type I (50-55 kDa) and II (70-75 kDa) activin receptors, but the mechanism of inhibin action is unclear. Proposed models range from an anti-activin action at the type II activin receptor to independent actions involving putative inhibin receptors. Two membrane-embedded proteoglycans, betaglycan and p120, have recently been implicated in inhibin binding, but neither appears to be a signalling receptor. The present studies on primary cultures of rat pituitary and adrenal cells, and several murine and human cell lines were undertaken to characterise inhibin binding to its physiological targets. High affinity binding of inhibin to the primary cultures and several of the cell lines, like that previously described for ovine pituitary cells, was saturable and reversible. Scatchard analysis revealed two classes of binding sites (K(d) of 40-400 and 500-5000 pM, respectively). Affinity labelling identified [125I]inhibin binding proteins with apparent molecular weights of 41, 74, 114 and >170 kDa in all cell types that displayed high affinity, high capacity binding of inhibin. Additional labelling of a 124 kDa species was evident in gonadal TM3 and TM4 cell lines. In several cases, activin (> or =20 nM) competed poorly or not at all for binding to these proteins. The 74, 114 and >170 kDa inhibin binding proteins in TM3 and TM4 cells were immunoprecipitated by an anti-betaglycan antiserum. These three proteins correspond in size to the activin receptor type II and the core protein and glycosylated forms of betaglycan, respectively, that have been proposed to mediate anti-activin actions of inhibin, but the identity of the 74 kDa species is yet to be confirmed. Studies of [125I]inhibin binding kinetics and competition for affinity labelling of individual binding proteins in several cell lines suggest these three species and the 41 and 124 kDa proteins form a high affinity inhibin binding complex. In summary, common patterns of inhibin binding and affinity labelling were observed in inhibin target cells. Novel inhibin binding proteins of around 41 and 124 kDa were implicated in the high affinity binding of inhibin to cells from several sources.
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Affiliation(s)
- P G Farnworth
- Prince Henry's Institute of Medical Research, P.O. Box 5152, 3168, Victoria, Clayton, Australia.
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Rahman NA, Huhtaniemi IT. Ovarian tumorigenesis in mice transgenic for murine inhibin alpha subunit promoter-driven Simian Virus 40 T-antigen: ontogeny, functional characteristics, and endocrine effects. Biol Reprod 2001; 64:1122-30. [PMID: 11259258 DOI: 10.1095/biolreprod64.4.1122] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
We previously reported formation of ovarian granulosa cell tumors with 100% penetration in a transgenic mouse model with murine inhibin alpha subunit promoter-driven (inhalpha)/Simian Virus 40 T-antigen (Tag). The tumor-bearing inhalpha/Tag mice showed highly elevated serum levels of immunoreactive inhibin. To investigate the onset of tumorigenesis and related endocrine consequences, 6-8 female mice of two inhalpha/Tag lines and their mating control littermates were killed monthly between 1 and 6 mo of age. We also investigated tumorigenesis-related fertility aspects of these two mouse lines. The ontogeny and progression of tumors could be monitored in both inhalpha/Tag lines by alterations of ovarian weights and serum hormone levels. Serum progesterone levels increased in both inhalpha/Tag lines in an age-dependent manner as ovarian tumorigenesis progressed, and a reciprocal decrease occurred in serum LH and FSH. Neither serum estradiol (E(2)) nor uterine weights were significantly altered during tumorigenesis, suggesting that the ovarian tumors represented late stages of granulosa cell differentiation. In conclusion, the present findings show in the inhalpha/Tag TG mice a relation between endocrine consequences of granulosa cell tumorigenesis, and a connection of onset of tumor formation with aberrant steroidogenesis and gonadotropin secretion. These findings indicate that tumors are endocrinologically active and able to exert enhanced negative feedback effects on pituitary function. The tumors provide a good model for endocrinologically active hormone-dependent tumors.
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Affiliation(s)
- N A Rahman
- Department of Physiology, University of Turku, 20520 Turku, Finland
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Rahman NA, Huhtaniemi I. Hormonal regulation of proliferation of granulosa and Leydig cell lines derived from gonadal tumors of transgenic mice expressing the inhibin-alpha subunit promoter/simian virus 40 T-antigen fusion gene. Mol Cell Endocrinol 1999; 149:9-17. [PMID: 10375013 DOI: 10.1016/s0303-7207(99)00004-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
We have produced a transgenic (TG) mouse model expressing the Simian Virus 40 T-antigen (Tag) gene, driven by a 6-kb fragment of the mouse inhibin-alpha subunit promoter (inh-alpha). The mice develop gonadal tumors with 100% penetrance by the age of 5-8 months, of granulosa cell origin in the ovary, and of Leydig cell origin in the testis. In the present study, we characterized the hormonal regulation of proliferation of two immortalized cell lines, BLT-1, originating from a Leydig cell tumor, and NT-1, originating from a granulosa cell tumor. [3H]-thymidine incorporation in both types of cells was stimulated by activin (> or = 10-30 microg/l), while inhibin had no effect. Transforming growth factor (TGF)-beta, at > or = 0.01 microg/l, stimulated proliferation of the granulosa tumor cells, but no effect was found on the Leydig tumor cells. Progesterone inhibited the proliferation of both cell lines, although the granulosa tumor cells were clearly less sensitive than the Leydig cells to this effect ( > or = 3 micromol/l vs. > 10 nmol/l, respectively). hCG had no effect on the Leydig tumor cell DNA synthesis whereas at high concentration (100 microg/l) it stimulated that of the granulosa cells. We also investigated in BLT-1 and NT-1 cells whether the proliferative changes were related to concomitant changes in Tag expression. In BLT-1 cells, this was stimulated by activin, progesterone and hCG, even though the latter substance did not affect cell proliferation. In contrast, TGF-beta inhibited Tag expression. In NT-1 cells, the expression of Tag was stimulated by activin, while hCG had no effect. In contrast, it was reduced by progesterone, inhibin and TGF-beta. In conclusion, our results indicate that the granulosa and Leydig tumor cells, despite similar mechanism of immortalization, respond differently to several mitotic stimuli. The responses in the level of Tag expression in these cells did not always correlate with the changes observed in cell proliferation, indicating the independence of these two phenomena.
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