Displaying publications 81 - 100 of 765 in total

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  1. Synthesis, α-amylase inhibitory potential and molecular docking study of indole derivatives
    Taha M, Baharudin MS, Ismail NH, Imran S, Khan MN, Rahim F, et al.
    Bioorg Chem, 2018 10;80:36-42.
    PMID: 29864686 DOI: 10.1016/j.bioorg.2018.05.021
    In search of potent α-amylase inhibitor we have synthesized eighteen indole analogs (1-18), characterized by NMR and HR-EIMS and screened for α-amylase inhibitory activity. All analogs exhibited a variable degree of α-amylase inhibition with IC50 values ranging between 2.031 ± 0.11 and 2.633 ± 0.05 μM when compared with standard acarbose having IC50 values 1.927 ± 0.17 μM. All compounds showed good α-amylase inhibition. Compound 14 was found to be the most potent analog among the series. Structure-activity relationship has been established for all compounds mainly based on bringing about the difference of substituents on phenyl ring. To understand the binding interaction of the most active analogs molecular docking study was performed.
    Matched MeSH terms: Magnetic Resonance Imaging
  2. Fulltext Synthesis, spectroscopic and chromatographic studies of sunflower oil biodiesel using optimized base catalyzed methanolysis
    Naureen R, Tariq M, Yusoff I, Chowdhury AJ, Ashraf MA
    Saudi J Biol Sci, 2015 May;22(3):332-9.
    PMID: 25972756 DOI: 10.1016/j.sjbs.2014.11.017
    Methyl esters from vegetable oils have attracted a great deal of interest as substitute for petrodiesel to reduce dependence on imported petroleum and provide an alternate and sustainable source for fuel with more benign environmental properties. In the present study biodiesel was prepared from sunflower seed oil by transesterification by alkali-catalyzed methanolysis. The fuel properties of sunflower oil biodiesel were determined and discussed in the light of ASTM D6751 standards for biodiesel. The sunflower oil biodiesel was chemically characterized with analytical techniques like FT-IR, and NMR ((1)H and (13)C). The chemical composition of sunflower oil biodiesel was determined by GC-MS. Various fatty acid methyl esters (FAMEs) were identified by retention time data and verified by mass fragmentation patterns. The percentage conversion of triglycerides to the corresponding methyl esters determined by (1)H NMR was 87.33% which was quite in good agreement with the practically observed yield of 85.1%.
    Matched MeSH terms: Magnetic Resonance Imaging
  3. Synthesis, molecular docking, dynamic simulations, kinetic mechanism, cytotoxicity evaluation of N-(substituted-phenyl)-4-{(4-[(E)-3-phenyl-2-propenyl]-1-piperazinyl} butanamides as tyrosinase and melanin inhibitors: In vitro, in vivo and in silico approaches
    Raza H, Abbasi MA, Aziz-Ur-Rehman, Siddiqui SZ, Hassan M, Abbas Q, et al.
    Bioorg Chem, 2020 01;94:103445.
    PMID: 31826809 DOI: 10.1016/j.bioorg.2019.103445
    In the current research work, different N-(substituted-phenyl)-4-{(4-[(E)-3-phenyl-2-propenyl]-1-piperazinyl}butanamides have been synthesized according to the protocol described in scheme 1. The synthesis was initiated by reacting various substituted anilines (1a-e) with 4-chlorobutanoyl chloride (2) in aqueous basic medium to give various electrophiles, 4-chloro-N-(substituted-phenyl)butanamides (3a-e). These electrophiles were then coupled with 1-[(E)-3-phenyl-2-propenyl]piperazine (4) in polar aprotic medium to attain the targeted N-(substituted-phenyl)-4-{(4-[(E)-3-phenyl-2-propenyl]-1-piperazinyl}butanamides (5a-e). The structures of all derivatives were identified and characterized by proton-nuclear magnetic resonance (1H NMR), carbon-nuclear magnetic resonance (13C NMR) and Infra-Red (IR) spectral data along with CHN analysis. The in vitro inhibitory potential of these butanamides was evaluated against Mushroom tyrosinase, whereby all compounds were found to be biologically active. Among them, 5b exhibited highest inhibitory potential with IC50 value of 0.013 ± 0.001 µM. The same compound 5b was also assayed through in vivo approach, and it was explored that it significantly reduced the pigments in zebrafish. The in silico studies were also in agreement with aforesaid results. Moreover, these molecules were profiled for their cytotoxicity through hemolytic activity, and it was found that except 5e, all other compounds showed minimal toxicity. The compound 5a also exhibited comparable results. Hence, some of these compounds might be worthy candidates for the formulation and development of depigmentation drugs with minimum side effects.
    Matched MeSH terms: Magnetic Resonance Imaging
  4. Synthesis, in vitro evaluation and molecular docking studies of biscoumarin thiourea as a new inhibitor of α-glucosidases
    Zawawi NK, Taha M, Ahmat N, Ismail NH, Wadood A, Rahim F, et al.
    Bioorg Chem, 2015 Dec;63:36-44.
    PMID: 26432614 DOI: 10.1016/j.bioorg.2015.09.004
    Biscoumarin analogs 1-18 have been synthesized, characterized by EI-MS and (1)H NMR and evaluated for α-glucosidase inhibitory potential. All compounds showed variety of α-glucosidase inhibitory potential ranging in between 13.5±0.39 and 104.62±0.3μM when compared with standard acarbose having IC50 value 774.5±1.94μM. The binding interactions of the most active analogs were confirmed through molecular docking. The compounds showed very good interactions with enzyme. All synthesized compounds 1-18 are new. Our synthesized compounds can further be studied to developed lead compounds.
    Matched MeSH terms: Magnetic Resonance Imaging
  5. Synthesis of potent urease inhibitors based on disulfide scaffold and their molecular docking studies
    Taha M, Ismail NH, Imran S, Wadood A, Rahim F, Riaz M
    Bioorg Med Chem, 2015 Nov 15;23(22):7211-8.
    PMID: 26507431 DOI: 10.1016/j.bmc.2015.10.017
    Disulfide analogs (1-20) have been synthesized, characterized by HR-MS, (1)H NMR and (13)C NMR and screened for urease inhibitory potential. All compounds were found to have varied degree of urease inhibitory potential ranging in between 0.4 ± 0.01 and 18.60 ± 1.24 μM when compared with standard inhibitor thiourea with IC50 19.46 ± 1.20 μM. Structure activity relationship has been established. The binding interactions of compounds with enzyme were confirmed through molecular docking. All the synthesized compounds 1-20 are new. Our compounds are cheaply synthesizable with high yield and can further be studied to discovery lead compounds. We further, tested for carbonic anhydrase, PDE1 and butyrylcholinesterase but they show no activity. On the other hand we evaluated all compounds for cytotoxicity they showed no toxicity.
    Matched MeSH terms: Magnetic Resonance Imaging
  6. Fulltext Synthesis of New Star-Shaped Liquid Crystalline Cyclotriphosphazene Derivatives with Fire Retardancy Bearing Amide-Azo and Azo-Azo Linking Units
    Jamain Z, Khairuddean M, Guan-Seng T
    Int J Mol Sci, 2020 Jun 16;21(12).
    PMID: 32560033 DOI: 10.3390/ijms21124267
    Two series of new hexasubstituted cyclotriphosphazene derivatives were successfully synthesized and characterized. These derivatives are differentiated by two types of linking units in the molecules such as amide-azo (6a-j) and azo-azo (8a-j). The homologues of the same series contain different terminal substituents such as heptyl, nonyl, decyl, dodecyl, tetradecyl, hydroxyl, carboxyl, chloro, nitro, and amino groups. All the intermediates and final compounds were characterized using Fourier transform infrared spectroscopy (FT-IR), nuclear magnetic resonance spectroscopy (NMR), and Carbon, Hydrogen, and Nitrogen (CHN) elemental analysis. Liquid crystal properties for all compounds were determined using polarized optical microscope (POM). It was found that only intermediates 2a-e with nitro and alkoxyl terminal chains showed a smectic A phase. All the final compounds with alkoxyl substituents are mesogenic with either smectic A or C phases. However, other intermediates and compounds were found to be non-mesogenic. The study on the fire retardancy of final compounds was determined using limiting oxygen index (LOI) method. The LOI value of pure polyester resin (22.53%) was increased up to 24.71% after treating with 1 wt% of hexachlorocyclotriphosphazene (HCCP). Moreover, all the compounds gave positive results on the LOI values and compound 6i with the nitro terminal substituent showed the highest LOI value of 27.54%.
    Matched MeSH terms: Magnetic Resonance Imaging
  7. Synthesis of 4-thiazolidinone analogs as potent in vitro anti-urease agents
    Rahim F, Zaman K, Ullah H, Taha M, Wadood A, Javed MT, et al.
    Bioorg Chem, 2015 Dec;63:123-31.
    PMID: 26520885 DOI: 10.1016/j.bioorg.2015.10.005
    4-Thiazolidinone analogs 1-20 were synthesized, characterized by (1)H NMR and EI-MS and investigated for urease inhibitory activity. All twenty (20) analogs exhibited varied degree of urease inhibitory potential with IC50 values 1.73-69.65μM, if compared with standard thiourea having IC50 value of 21.25±0.15μM. Among the series, eight derivatives 3, 6, 8, 10, 15, 17, 19, and 20 showed outstanding urease inhibitory potential with IC50 values of 9.34±0.02, 14.62±0.03, 8.43±0.01, 7.3±0.04, 2.31±0.002, 5.75±0.003, 8.81±0.005, and 1.73±0.001μM, respectively, which is better than the standard thiourea. The remaining analogs showed good to excellent urease inhibition. The binding interactions of these compounds were confirmed through molecular docking studies.
    Matched MeSH terms: Magnetic Resonance Imaging
  8. Synthesis and characterization of some diorganotin(IV) complexes of 2,3-dihydroxybenzaldehyde N(4)-substituted thiosemicarbazone
    Swesi AT, Yang Farina, Ibrahim Baba
    Sains Malaysiana, 2007;36:21-26.
    Organotin compounds especially the dialkyltin derivatives are reported to possess anti-tumour properties. The diorganotin(IV) complexes of the type Me2SnL1, Me2SnL2, Bu2SnL1, Bu2SnL2 and Ph2SnL1 (L1 and L2 is the anion of the thiosemicarbazone ligand formed by the condensation reaction of 2,3-dihydroxybenzaldehyde with thiosemicarbazide or its N(4)-methyl substituent) were synthesized using 1:1 metal-to-ligand reactant ratios. The newly synthesized complexes were characterized using elemental analysis, infrared and nuclear magnetic resonance (1H, 13C, 119Sn) spectroscopic techniques. Complex formation between the organotin(IV) moiety and the anions of 2,3-dihydroxybenzaldehyde thiosemicarbazone and 2,3-dihydroxybenzaldehyde 4-methylthiosemicarbazone occurred with chelation at the o-dihydroxy positions. The complexes are proposed to have tetrahedral geometry.
    Matched MeSH terms: Magnetic Resonance Imaging
  9. Fulltext Synthesis and characterization of novel dimeric ionic liquids by conventional approaches
    Ganesan K, Alias Y
    Int J Mol Sci, 2008 Jun;9(7):1207-13.
    PMID: 19325800 DOI: 10.3390/ijms9071207
    The (1)H-NMR shifts of the imidazolium protons of some novel dimeric ionic liquids were examined in various deuterated solvents. Interactions between the solvent and the imidazolium salt of butyl substituted ionic liquids were observed to give higher chemical shifts than methyl substitution.
    Matched MeSH terms: Magnetic Resonance Imaging
  10. Synthesis and characterization of esters derived from ricinoleic acid and evaluation of their low temperature property
    Jumat Salimon, Nadia Salih, Yousif E
    Sains Malaysiana, 2012;41:1239-1244.
    A series of ester compounds derived from ricinoleic acid to be used as biolubricants base stock have been synthesized. The resulting products were confirmed by FTIR and NMR analyses. The synthesis was carried out in three stages: epoxidation of ricinoleic acid; synthesis of 10,12-dihydroxy-9-acyloxystearic acid from epoxidized ricinoleic acid with various fatty acids and esterification of the acyloxystearic acid products with octanol to yield octyl-10,12-dihydroxy-9-acyloxystearate. The viscosities, flash points and pour points (PP) behavior of the products were measured. The resulting esters had an increased in molar weight and viscosity and decreased in pour points as compared to ricinoleic acid.
    Matched MeSH terms: Magnetic Resonance Imaging
  11. Fulltext Synovial Sarcoma- An unusual cause of Heel Pain
    Norhamdan, M.Y., Shahril, Y, Masbah, O., Siti Aishah, M.A.
    Malays Orthop J, 2008;2(2):31-33.
    MyJurnal
    We report a case of 29-year-old female who presented with right heel pain that worsened over a period of two years. The onset of pain was followed by swelling at the medial aspect of right ankle. She was initially treated for plantar fasciitis with multiple steroid injections over the heel. Subsequent MRI revealed a well-defined heterogeneous lesion in continuity with the medial plantar nerve. Excision biopsy was performed and histopathological evaluation revealed monophasic synovial sarcoma. The patient subsequently underwent wide resection and free tissue transfer followed by radiotherapy and chemotherapy. This case highlights an unusual site and presentation of synovial sarcoma which led to delayed diagnosis and treatment.
    Matched MeSH terms: Magnetic Resonance Imaging
  12. Fulltext Synovial Haemangioma of the Elbow: A rare paediatric case and imaging dilemma
    Hoe HG, Zaki FM, Rashid AHA
    Sultan Qaboos Univ Med J, 2018 Feb;18(1):e93-e96.
    PMID: 29666688 DOI: 10.18295/squmj.2018.18.01.015
    Synovial haemangiomas are rare benign vascular proliferations arising in synovium-lined surfaces. While the knee is by far the joint most commonly involved, this condition can also occur in the elbow. We report an eight-year-old boy who presented to the National University of Malaysia Medical Centre, Kuala Lumpur, Malaysia, in 2016 with a left elbow swelling of one year's duration. Magnetic resonance imaging showed a lobulated intra-articular mass with intermediate signal intensity on T1-weighted imaging and low signal punctate and linear structures within the hyperintense mass on T2-weighted imaging. In addition, there was heterogeneous yet avid contrast enhancement on post-gadolinium contrast images. The mass had juxta-articular extension and bony erosion to the coronoid process and the head of the radius. Synovial haemangiomas present a diagnostic dilemma. This report highlights certain imaging characteristics to distinguish this entity from other differential diagnoses.
    Matched MeSH terms: Magnetic Resonance Imaging/methods*
  13. Fulltext Synovial Cyst: A Culprit for Recalcitrant Iliotibial Band Syndrome: A Case Report
    Yeoh C, Lim G, Sathappan SS
    Malays Orthop J, 2015 Nov;9(3):68-70.
    PMID: 28611916 DOI: 10.5704/MOJ.1511.011
    We present the case of a 56-year old gentleman who presented with recalcitrant iliotibial band (ITB) friction syndrome which did not improve with various modalities of conservative treatment. Magnetic Resonance Imaging (MRI) of the affected knee did not show pathology typical of ITB friction syndrome. However, open exploration revealed a synovial cyst deep to the iliotibial band, abutting against the anterolateral capsule. The presence of distinctive clinical signs on physical examination should alert clinicians to consider knee synovial cyst as a differential diagnosis when dealing with recalcitrant ITB syndrome.
    Matched MeSH terms: Magnetic Resonance Imaging
  14. Symptomatic spinal epidural lipomatosis after a single local epidural steroid injection
    Tok CH, Kaur S, Gangi A
    Cardiovasc Intervent Radiol, 2011 Feb;34 Suppl 2:S250-5.
    PMID: 20859631 DOI: 10.1007/s00270-010-9982-z
    Spinal epidural lipomatosis is a rare disorder that can manifest with progressive neurological deficits. It is characterized by abnormal accumulation of unencapsulated epidural fat commonly associated with the administration of exogenous steroids associated with a variety of systemic diseases, endocrinopathies, and Cushing syndrome (Fogel et al. Spine J 5:202-211, 2005). Occasionally, spinal epidural lipomatosis may occur in patients not exposed to steroids or in patients with endocrinopathies, primarily in obese individuals (Fogel et al. Spine J 5:202-211, 2005). However, spinal lumbar epidural lipomatosis resulting from local steroid injection has rarely been reported. We report the case of a 45-year-old diabetic man with claudication that was probably due to symptomatic lumbar spinal lipomatosis resulting from a single local epidural steroid injection.
    Matched MeSH terms: Magnetic Resonance Imaging
  15. Fulltext Symptomatic intra-articular ganglion cyst of the knee
    Aminudin CA, Samsudin OC, Hyzan MY, Hamzaini AH, Zahiah M
    Med J Malaysia, 2004 Dec;59 Suppl F:57-9.
    PMID: 15941165
    We are reporting a case of a patient with a symptomatic intra-articular ganglion of the knee arising from infrapatellar fat pad. Plain radiograph and Magnetic Resonance (MR) images were correlated with arthroscopic examination and histological findings. The cyst was removed and post operatively patient regained full extension.
    Matched MeSH terms: Magnetic Resonance Imaging
  16. Fulltext Surgical access to parapharyngeal space tumours--the Manipal experience
    Hazarika P, Dipak RN, Parul P, Kailesh P
    Med J Malaysia, 2004 Aug;59(3):323-9.
    PMID: 15727377
    A few series of parapharyngeal space tumours have been reported earlier but recently not many series have been published in English literature. It is rare for any medical center, let alone an individual surgeon, to develop sufficient experience in evaluating these tumours. We present our experience in the treatment of 41 cases of parapharyngeal tumours from January 1992 to December 2001. FNAC, ultrasound and CT scan of the presenting mass was done in most of the patients as the main pre-operative work-up. The strategic location and extension of the tumour may occasionally alter the surgical approach for tumour excision.
    Matched MeSH terms: Magnetic Resonance Imaging
  17. Suprasellar lymphoma masquerading as tuberculosis of the central nervous system
    Dang YL, Hor JY, Chia YK, Lim TT, Eow GB
    Acta Neurol Belg, 2014 Sep;114(3):239-41.
    PMID: 23757110 DOI: 10.1007/s13760-013-0217-3
    Matched MeSH terms: Magnetic Resonance Imaging
  18. Succinic Semialdehyde Dehydrogenase Deficiency in a Chinese Boy: A Novel ALDH5A1 Mutation With Severe Phenotype
    Tay CG, Ariffin H, Yap S, Rahmat K, Sthaneshwar P, Ong LC
    J Child Neurol, 2015 Jun;30(7):927-31.
    PMID: 25122112 DOI: 10.1177/0883073814540523
    Succinic semialdehyde dehydrogenase deficiency is a rare autosomal recessive disorder affecting catabolism of the neurotransmitter gamma-aminobutyric acid (GABA), with a wide range of clinical phenotype. We report a Malaysian Chinese boy with a severe early onset phenotype due to a previously unreported mutation. Urine organic acid chromatogram revealed elevated 4-hydroxybutyric acid. Magnetic resonance imaging (MRI) of the brain demonstrated cerebral atrophy with atypical putaminal involvement. Molecular genetic analysis showed a novel homozygous 3-bp deletion at the ALDH5A1 gene c.1501_1503del (p.Glu501del). Both parents were confirmed to be heterozygotes for the p.Glu501del mutation. The clinical course was complicated by the development of subdural hemorrhage probably as a result of rocking the child to sleep for erratic sleep-wake cycles. This case illustrates the need to recognize that trivial or unintentional shaking of such children, especially in the presence of cerebral atrophy, can lead to subdural hemorrhage.
    Matched MeSH terms: Magnetic Resonance Imaging
  19. Fulltext Successful surgical strategy for ventral thoracic spinal perimedullary spinal arteriovenous fistulas: Case report
    Subramaniam SM, Ishii K, Sheng CJ, Nakatomi H, Takai K, Saito N
    Surg Neurol Int, 2019;10:251.
    PMID: 31893152 DOI: 10.25259/SNI_516_2019
    Background: Spinal arteriovenous fistulas (AVFs) are vascular lesions that often pose significant surgical challenges. This is particularly true for those located close to the anterior spinal artery. Here, we analyzed the surgical options for treating an anterior perimedullary AVF (pAVFs).

    Case Description: A 66-year-old male with the right lower extremity weakness was diagnosed with a spinal dural AVF at the L1 level. It was initially treated with open surgery followed by CyberKnife radiosurgery at another institution. Five years later, he presented with a persistent pAVF fistula now involving the T11 level; the major feeder originated on the left at the T7-T8 level (e.g., involving a left-sided "duplicated" anterior spinal artery). Utilizing a three-dimensional (3D) computer tomography (CT) guided approach; he underwent a left-sided posterolateral T10-T12 laminectomy, sufficient to allow for 30-40° of anterior spinal cord rotation. This was performed under neurophysiological monitoring without any significant changes. Surgery included indocyanine green video angiography, temporary feeder clipping, and complete occlusion of the AVF, followed by complete clipping/resection as confirmed on postoperative magnetic resonance imaging.

    Conclusion: Utilizing a 3D CT image, a ventral pulmonary arteriovenous malformation was excised utilizing a left-sided posterolateral approach allowing for 30-40° of cord rotation.

    Matched MeSH terms: Magnetic Resonance Imaging
  20. Fulltext Subungual Glomus Tumours: Is Magnetic Resonance Imaging or Ultrasound Necessary for Diagnosis?
    Pandey CR, Singh N, Tamang B
    Malays Orthop J, 2017 Mar;11(1):47-51.
    PMID: 28435574 DOI: 10.5704/MOJ.1703.020
    INTRODUCTION: Diagnosis of subungual glomus tumour is mostly based on detailed history and clinical examination. Recently, Magnetic Resonance Imaging (MRI) and Ultrasound have been proposed as the imaging modality to confirm the clinical diagnosis and in planning the surgical management of these tumours. However, these imaging modalities are not routinely available in rural setting and also are expensive. Due to these limitations, we set out to establish that diagnosis and management of these rare tumours can be based solely on a battery of clinical tests and history taking.

    MATERIALS AND METHODS: Retrospectively, we reviewed nine cases of glomus tumour. A clinical evaluation proforma was developed on the basis of clinical history and specific clinical test for diagnosis of these tumours. All the cases were evaluated and treated surgically by a single surgeon with a specific technique. Post-operatively, diagnosis was confirmed by histopathological examination.

    RESULTS: Females (77.78%) were predominantly affected in this series and the tumours commonly occurred in the right hand (66.66%). Spontaneous pain, cold sensitivity test and Love's Pin test was positive in all cases (100%). Hildreth's test was positive in 88.89%. In none of the cases the tumours recurred during minimum follow-up of one year. In all cases, histopathological examination confirmed the preoperative diagnosis of glomus tumours.

    CONCLUSION: Diagnosis of glomus tumours can be made clinically based on history taking and clinical examination. Magnetic Resonance Imaging and Ultrasound are not necessary for diagnosis and management of typical subungual tumours.

    Matched MeSH terms: Magnetic Resonance Imaging
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