Displaying publications 21 - 40 of 95 in total

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  1. Repurposing of Drugs Is a Viable Approach to Develop Therapeutic Strategies against Central Nervous System Related Pathogenic Amoebae
    Anwar A, Khan NA, Siddiqui R
    ACS Chem Neurosci, 2020 08 19;11(16):2378-2384.
    PMID: 32073257 DOI: 10.1021/acschemneuro.9b00613
    Brain-eating amoebae including Acanthamoeba spp., Naegleria fowleri, and Balamuthia mandrillaris cause rare infections of the central nervous system that almost always result in death. The high mortality rate, lack of interest for drug development from pharmaceutical industries, and no available effective drugs present an alarming challenge. The current drugs employed in the management and therapy of these devastating diseases are amphotericin B, miltefosine, chlorhexidine, pentamidine, and voriconazole which are generally used in combination. However, clinical evidence shows that these drugs have limited efficacy and high host cell cytotoxicity. Repurposing of drugs is a practical approach to utilize commercially available, U.S. Food and Drug Administration approved drugs for one disease against rare diseases caused by brain-eating amoebae. In this Perspective, we highlight some of the success stories of drugs repositioned against neglected parasitic diseases and identify future potential for effective and sustainable drug development against brain-eating amoebae infections.
  2. Fulltext Antimicrobial activities of green synthesized gums-stabilized nanoparticles loaded with flavonoids
    Anwar A, Masri A, Rao K, Rajendran K, Khan NA, Shah MR, et al.
    Sci Rep, 2019 02 28;9(1):3122.
    PMID: 30816269 DOI: 10.1038/s41598-019-39528-0
    Herein, we report green synthesized nanoparticles based on stabilization by plant gums, loaded with citrus fruits flavonoids Hesperidin (HDN) and Naringin (NRG) as novel antimicrobial agents against brain-eating amoebae and multi-drug resistant bacteria. Nanoparticles were thoroughly characterized by using zetasizer, zeta potential, atomic force microscopy, ultravoilet-visible and Fourier transform-infrared spectroscopic techniques. The size of these spherical nanoparticles was found to be in the range of 100-225 nm. The antiamoebic effects of these green synthesized Silver and Gold nanoparticles loaded with HDN and NRG were tested against Acanthamoeba castellanii and Naegleria fowleri, while antibacterial effects were evaluated against methicillin-resistant Staphylococcus aureus (MRSA) and neuropathogenic Escherichia coli K1. Amoebicidal assays revealed that HDN loaded Silver nanoparticles stabilized by gum acacia (GA-AgNPs-HDN) quantitatively abolished amoeba viability by 100%, while NRG loaded Gold nanoparticles stabilized by gum tragacanth (GT-AuNPs-NRG) significantly reduced the viability of A. castellanii and N. fowleri at 50 µg per mL. Furthermore, these nanoparticles inhibited the encystation and excystation by more than 85%, as well as GA-AgNPs-HDN only completely obliterated amoeba-mediated host cells cytopathogenicity. Whereas, GA-AgNPs-HDN exhibited significant bactericidal effects against MRSA and E. coli K1 and reduced bacterial-mediated host cells cytotoxicity. Notably, when tested against human cells, these nanoparticles showed minimal (23%) cytotoxicity at even higher concentration of 100 µg per mL as compared to 50 µg per mL used for antimicrobial assays. Hence, these novel nanoparticles formulations hold potential as therapeutic agents against infections caused by brain-eating amoebae, as well as multi-drug resistant bacteria, and recommend a step forward in drug development.
  3. Brain-eating Amoebae Infection: Challenges and Opportunities in Chemotherapy
    Mungroo MR, Anwar A, Khan NA, Siddiqui R
    Mini Rev Med Chem, 2019;19(12):980-987.
    PMID: 30868950 DOI: 10.2174/1389557519666190313161854
    Pathogenic free-living amoeba are known to cause a devastating infection of the central nervous system and are often referred to as "brain-eating amoebae". The mortality rate of more than 90% and free-living nature of these amoebae is a cause for concern. It is distressing that the mortality rate has remained the same over the past few decades, highlighting the lack of interest by the pharmaceutical industry. With the threat of global warming and increased outdoor activities of public, there is a need for renewed interest in identifying potential anti-amoebic compounds for successful prognosis. Here, we discuss the available chemotherapeutic options and opportunities for potential strategies in the treatment and diagnosis of these life-threatening infections.
  4. Fulltext Gold-Conjugated Curcumin as a Novel Therapeutic Agent against Brain-Eating Amoebae
    Mungroo MR, Anwar A, Khan NA, Siddiqui R
    ACS Omega, 2020 Jun 02;5(21):12467-12475.
    PMID: 32548431 DOI: 10.1021/acsomega.0c01305
    Balamuthia mandrillaris and Naegleria fowleri are free-living amoebae that cause infection of the central nervous system, granulomatous amoebic encephalitis (GAE) and primary amoebic meningoencephalitis (PAM), respectively. The fact that mortality rates for cases of GAE and PAM are more than 95% indicates the need for new therapeutic agents against those amoebae. Considering that curcumin exhibits a wide range of biological properties and has shown efficacy against Acanthamoeba castellanii, we evaluated the amoebicidal properties of curcumin against N. fowleri and B. mandrillaris. Curcumin showed significant amoebicidal activities with an AC50 of 172 and 74 μM against B. mandrillaris and N. fowleri, respectively. Moreover, these compounds were also conjugated with gold nanoparticles to further increase their amoebicidal activities. After conjugation with gold nanoparticles, amoebicidal activities of the drugs were increased by up to 56 and 37% against B. mandrillaris and N. fowleri, respectively. These findings are remarkable and suggest that clinically available curcumin and our gold-conjugated curcumin nanoparticles hold promise in the improved treatment of fatal infections caused by brain-eating amoebae and should serve as a model in the rationale development of therapeutic interventions against other infections.
  5. Future Priorities in Tackling Infections Due to Brain-Eating Amoebae
    Khan NA, Anwar A, Siddiqui R
    ACS Chem Neurosci, 2017 11 15;8(11):2355.
    PMID: 28933530 DOI: 10.1021/acschemneuro.7b00343
    Brain-eating amoebae (Acanthamoeba spp., Balamuthia mandrillaris, and Naegleria fowleri) can cause opportunistic infections involving the central nervous system. It is troubling that the mortality rate is more than 90% despite advances in antimicrobial chemotherapy over the last few decades. Here, we describe urgent key priorities for improving outcomes from infections due to brain-eating amoebae.
  6. Brain-Eating Amoebae: Silver Nanoparticle Conjugation Enhanced Efficacy of Anti-Amoebic Drugs against Naegleria fowleri
    Rajendran K, Anwar A, Khan NA, Siddiqui R
    ACS Chem Neurosci, 2017 12 20;8(12):2626-2630.
    PMID: 29206032 DOI: 10.1021/acschemneuro.7b00430
    The overall aim of this study was to determine whether conjugation with silver nanoparticles enhances effects of available drugs against primary amoebic meningoencephalitis due to Naegleria fowleri. Amphotericin B, Nystatin, and Fluconazole were conjugated with silver nanoparticles, and synthesis was confirmed using UV-visible spectrophotometry. Atomic force microscopy determined their size in range of 20-100 nm. To determine amoebicidal effects, N. fowleri were incubated with drugs-conjugated silver nanoparticles, silver nanoparticles alone, and drugs alone. The findings revealed that silver nanoparticles conjugation significantly enhanced antiamoebic effects of Nystatin and Amphotericin B but not Fluconazole at micromolar concentrations, compared with the drugs alone. For the first time, our findings showed that silver nanoparticle conjugation enhances efficacy of antiamoebic drugs against N. fowleri. Given the rarity of the disease and challenges in developing new drugs, it is hoped that modifying existing drugs to enhance their antiamoebic effects is a useful avenue that holds promise in improving the treatment of brain-eating amoebae infection due to N. fowleri.
  7. Fulltext Combating Acanthamoeba spp. cysts: what are the options?
    Anwar A, Khan NA, Siddiqui R
    Parasit Vectors, 2018 01 09;11(1):26.
    PMID: 29316961 DOI: 10.1186/s13071-017-2572-z
    Acanthamoeba spp. are protist pathogens and causative agents of serious infections including keratitis and granulomatous amoebic encephalitis. Its ability to convert into dormant and highly resistant cysts form limits effectiveness of available therapeutic agents and presents a pivotal challenge for drug development. During the cyst stage, Acanthamoeba is protected by the presence of hardy cyst walls, comprised primarily of carbohydrates and cyst-specific proteins, hence synthesis inhibition and/or degradation of cyst walls is of major interest. This review focuses on targeting of Acanthamoeba cysts by identifying viable therapeutic targets.
  8. Repositioning of Guanabenz in Conjugation with Gold and Silver Nanoparticles against Pathogenic Amoebae Acanthamoeba castellanii and Naegleria fowleri
    Anwar A, Mungroo MR, Anwar A, Sullivan WJ, Khan NA, Siddiqui R
    ACS Infect Dis, 2019 Dec 13;5(12):2039-2046.
    PMID: 31612700 DOI: 10.1021/acsinfecdis.9b00263
    Brain-eating amoebae cause devastating infections in the central nervous system of humans, resulting in a mortality rate of 95%. There are limited effective therapeutic options available clinically for treating granulomatous amoebic encephalitis and primary amoebic meningoencephalitis caused by Acanthamoeba castellanii (A. castellanii) and Naegleria fowleri (N. fowleri), respectively. Here, we report for the first time that guanabenz conjugated to gold and silver nanoparticles has significant antiamoebic activity against both A. castellanii and N. fowleri. Gold and silver conjugated guanabenz nanoparticles were synthesized by the one-phase reduction method and were characterized by ultraviolet-visible spectrophotometry and atomic force microscopy. Both metals were facilely stabilized by the coating of guanabenz, which was examined by surface plasmon resonance determination. The average size of gold nanoconjugated guanabenz was found to be 60 nm, whereas silver nanoparticles were produced in a larger size distribution with the average diameter of around 100 nm. Guanabenz and its noble metal nanoconjugates exhibited potent antiamoebic effects in the range of 2.5 to 100 μM against both amoebae. Nanoparticle conjugation enhanced the antiamoebic effects of guanabenz, as more potent activity was observed at a lower effective concentration (2.5 and 5 μM) compared to the drug alone. Moreover, encystation and excystation assays revealed that guanabenz inhibits the interconversion between the trophozoite and cyst forms of A. castellanii. Cysticdal effects against N. fowleri were also observed. Notably, pretreatment of A. castellanii with guanabenz and its nanoconjugates exhibited a significant reduction in the host cell cytopathogenicity from 65% to 38% and 2% in case of gold and silver nanoconjugates, respectively. Moreover, the cytotoxic evaluation of guanabenz and its nanoconjugates revealed negligible cytotoxicity against human cells. Guanabenz is already approved for hypertension and crosses the blood-brain barrier; the results of our current study suggest that guanabenz and its conjugated gold and silver nanoparticles can be repurposed as a potential drug for treating brain-eating amoebic infections.
  9. Fulltext Potential anti-amoebic effects of synthetic 1,4-benzothiazine derivatives against Acanthamoeba castellanii
    Alishba, Ahmed U, Taha M, Khan NA, Salar U, Khan KM, et al.
    Heliyon, 2024 Jan 15;10(1):e23258.
    PMID: 38205285 DOI: 10.1016/j.heliyon.2023.e23258
    A rare but lethal central nervous system disease known as granulomatous amoebic encephalitis (GAE) and potentially blinding Acanthamoeba keratitis are diseases caused by free-living Acanthamoeba. Currently, no therapeutic agent can completely eradicate or prevent GAE. Synthetic compounds are a likely source of bioactive compounds for developing new drugs. This study synthesized seventeen 1,4-benzothiazine derivatives (I -XVII) by a base-catalyzed one-pot reaction of 2-amino thiophenol with substituted bromo acetophenones. Different spectroscopic techniques, such as EI-MS, 1H-, and 13C NMR (only for the new compounds), were used for the structural characterization and conformation of compounds. These compounds were assessed for the first time against Acanthamoeba castellanii. All compounds showed anti-amoebic potential in vitro against A. castellanii, reducing its ability to encyst and excyst at 100 μM. Compounds IX, X, and XVI showed the most potent activities among all derivatives and significantly reduced the viability to 5.3 × 104 (p 
  10. Applications of photodynamic therapy in keratitis
    Anwar A, Khan NA, Alharbi AM, Alhazmi A, Siddiqui R
    Int Ophthalmol, 2024 Mar 15;44(1):140.
    PMID: 38491335 DOI: 10.1007/s10792-024-03062-4
    Keratitis is corneal inflammatory disease which may be caused by several reason such as an injury, allergy, as well as a microbial infection. Besides these, overexposure to ultraviolet light and unhygienic practice of contact lenses are also associated with keratitis. Based on the cause of keratitis, different lines of treatments are recommended. Photodynamic therapy is a promising approach that utilizes light activated compounds to instigate either killing or healing mechanism to treat various diseases including both communicable and non-communicable diseases. This review focuses on clinically-important patent applications and the recent literature for the use of photodynamic therapy against keratitis.
  11. Pyrazinium thioacetate capped gold nanoparticles as Fe(III) sensor and Fe(III) marked anti-proliferating agent in human neuroblastoma cells
    Anwar A, Minhaz A, Hussain SS, Anwar A, Simjee SU, Ishaq M, et al.
    Spectrochim Acta A Mol Biomol Spectrosc, 2019 Jan 05;206:135-140.
    PMID: 30096697 DOI: 10.1016/j.saa.2018.07.099
    Gold nanoparticles (AuNPs) stabilized by new cationic 1‑(3‑(acetylthio)propyl)pyrazin‑1‑ium ligand (PPTA) were synthesized. AuNPs stabilized by PPTA (PPTA-AuNPs) were found to be spherical and polydispersed with the average size of 60 nm. Human neuroblastoma (SHSY-5Y) cells permeability of PPTA-AuNPs was found to be a key feature to study the intracellular quenching of Fe(III) proliferative activity. In vitro MTT assay revealed non-cytotoxicity of PPTA and PPTA-AuNPs at 100 μM concentration, while treatment of 100 μM of Fe(III) with SHSY-5Y cells resulted into higher cells viability. Contrary, a mixture of 1:1 Fe(III) with PPTA-AuNPs showed no change in the viability of cells at same concentration which suggests the intracellular complexation and recognition of Fe(III) by PPTA-AuNPs. AFM morphological analysis of SHSY-5Y cells also supported the MTT assay results, and it is safe to conclude that PPTA-AuNPs can be used as Fe(III) probes in living cells. In addition, Fe(III) caused a significant decrease in the absorbance of surface plasmon resonance (SPR) band of PPTA-AuNPs in a wide range of concentration and pH, with limit of detection 4.3 μM. Moreover, the specific response of PPTA-AuNPs towards Fe(III) was unaffected by the interference of other metals and components of real samples of tap water.
  12. Fulltext Synthesis of 4-(dimethylamino)pyridine propylthioacetate coated gold nanoparticles and their antibacterial and photophysical activity
    Anwar A, Khalid S, Perveen S, Ahmed S, Siddiqui R, Khan NA, et al.
    J Nanobiotechnology, 2018 Jan 29;16(1):6.
    PMID: 29378569 DOI: 10.1186/s12951-017-0332-z
    BACKGROUND: Gold nanoparticles are useful candidate for drug delivery applications and are associated with enhancement in the bioavailability of coated drugs and/or therapeutic agent. Since, heterocyclic compounds are known to exhibit antimicrobial potential against variety of pathogens, we designed this study to evaluate the antibacterial effects of gold nanoparticles conjugation with new synthesized cationic ligand; 4-Dimethyl aminopyridinium propylthioacetate (DMAP-PTA) in comparison with pure compound and antibiotic drug Pefloxacin. Antibacterial activity of DMAP-PTA coated gold nanoparticles was investigated against a fecal strain of E. coli (ATCC 8739).

    RESULTS: A new dimethyl aminopyridine based stabilizing agent named as DMAP-PTA was synthesized and used for stabilization of gold nanoparticles. Gold nanoparticles coated with DMAP-PTA abbreviated as DMAP-PTA-AuNPs were thoroughly characterized by UV-visible, FT-IR spectroscopic methods and transmission electron microscope before biological assay. DMAP-PTA, DMAP-PTA-AuNPs and Pefloxacin were examined for their antibacterial potential against E. coli, and the minimum inhibitory concentration (MIC) was determined to be 300, 200 and 50 µg/mL respectively. Gold nanoparticles conjugation was found to significantly enhance the antibacterial activity of DMAP-PTA as compared to pure compound. Moreover, effects of DMAP-PTA-AuNPs on the antibacterial potential of Pefloxacin was also evaluated by combination therapy of 1:1 mixture of DMAP-PTA-AuNPs and Pefloxacin against E. coli in a wide range of concentrations from 5 to 300 µg/mL. The MIC of Pefloxacin + DMAP-PTA-AuNPs mixture was found to be 25 µg/mL as compared to Pefloxacin alone (50 µg/mL), which clearly indicates that DMAP-PTA-AuNPs increased the potency of Pefloxacin. AFM analysis was also carried out to show morphological changes occur in bacteria before and after treatment of test samples. Furthermore, DMAP-PTA-AuNPs showed high selectivity towards Pefloxacin in spectrophotometric drug recognition studies which offers tremendous potential for analytical applications.

    CONCLUSIONS: Gold nanoparticles conjugation was shown to enhance the antibacterial efficacy of DMAP-PTA ligand, while DMAP-PTA-AuNPs also induced synergistic effects on the potency of Pefloxacin against E. coli. DMAP-PTA-AuNPs were also developed as Pefloxacin probes in recognizing the drug in blood and water samples in the presence of other drugs.

  13. Fulltext Next generation sequencing reveals the antibiotic resistant variants in the genome of Pseudomonas aeruginosa
    Ramanathan B, Jindal HM, Le CF, Gudimella R, Anwar A, Razali R, et al.
    PLoS One, 2017;12(8):e0182524.
    PMID: 28797043 DOI: 10.1371/journal.pone.0182524
    Rapid progress in next generation sequencing and allied computational tools have aided in identification of single nucleotide variants in genomes of several organisms. In the present study, we have investigated single nucleotide polymorphism (SNP) in ten multi-antibiotic resistant Pseudomonas aeruginosa clinical isolates. All the draft genomes were submitted to Rapid Annotations using Subsystems Technology (RAST) web server and the predicted protein sequences were used for comparison. Non-synonymous single nucleotide polymorphism (nsSNP) found in the clinical isolates compared to the reference genome (PAO1), and the comparison of nsSNPs between antibiotic resistant and susceptible clinical isolates revealed insights into the genome variation. These nsSNPs identified in the multi-drug resistant clinical isolates were found to be altering a single amino acid in several antibiotic resistant genes. We found mutations in genes encoding efflux pump systems, cell wall, DNA replication and genes involved in repair mechanism. In addition, nucleotide deletions in the genome and mutations leading to generation of stop codons were also observed in the antibiotic resistant clinical isolates. Next generation sequencing is a powerful tool to compare the whole genomes and analyse the single base pair variations found within the antibiotic resistant genes. We identified specific mutations within antibiotic resistant genes compared to the susceptible strain of the same bacterial species and these findings may provide insights to understand the role of single nucleotide variants in antibiotic resistance.
  14. Fulltext Digital Students' Satisfaction With and Intention to Use Online Teaching Modes, Role of Big Five Personality Traits
    Mustafa S, Qiao Y, Yan X, Anwar A, Hao T, Rana S
    Front Psychol, 2022;13:956281.
    PMID: 35936293 DOI: 10.3389/fpsyg.2022.956281
    During the COVID-19 pandemic, online teaching modes were found vital to continue students' learning process, but sustainable implementation of online teaching models is an area of concern for policymakers. Psychiatrists are also eager to know students' behavior toward learning and modes of teaching during COVID-19. We have drawn a model based on the big five personality traits to study students' satisfaction with online teaching modes and their adoption intentions toward online teaching modes. We have collected data from 718 bachelor's and master's level students from four different universities. We have applied the SEM-ANN dual-stage approach to test personality traits' influence and ranked them based on their normalized importance. The results revealed that agreeableness, conscientiousness, neuroticism, and openness positively influence students' satisfaction with online teaching models, but that extraversion negatively influences their satisfaction. Agreeableness, extraversion, and neuroticism positively impact, but openness negatively influences. Conscientiousness does not affect adoption intention. Furthermore, agreeableness is the most significant, and conscientiousness is the least important factor for students to adopt online teaching modes. The findings of the study have useful perceptiveness for educational policymakers, academics, and psychiatrists.
  15. Fulltext Incidence of Helicobacter pylori Infection using (13) C- Urea BreathTest and Gastric Biopsy Culture
    Khairul, A.J., Anwar, A., Ramelah, M.
    International Medical Journal Malaysia, 2007;6(2):1-8.
    MyJurnal
    Background: (13) C – urea breath test (UBT) is sensitive and specific for detection of Helicobacter pylori (H. pylori) infection. Gastric biopsy culture for H. pylori confirms the diagnosis. Here, we analyzed data of all patients who were investigated for H. pylori infection using both tests throughout the year 2005. Materials and Methods : Retrospective data of 377 patients between the ages of 17 – 88 were identified through endoscopy records from January to December 2005. Upper endoscopy, UBT and gastric biopsy culture were performed on all patients simultaneously during each endoscopy session. Patients who had positive UBT and biopsy culture for H. pylori were treated with triple therapy of PPI, amoxicillin and clarithromycin for one week. A repeat of UBT was done at one-month post therapy. Results and Analysis: Twenty-eight patients on the list had no available data on UBT and were omitted from the analysis. Ethnic group Chinese comprised of 45.4% (n=163), followed by Malay, 37.3% (n=134), Indian, 10.6% (n=38) and others, 3.9% (n=14). UBT was positive in 23.7% (n=85)(figure1). H. pylori culture was positive in 19.2% (n=69)(figure1). Sixteen patients with UBT positive had H. pylori culture negative, 18.8% (n=16/85)(figure2). Five patients with H. pylori culture positive had UBT negative, 7.2% (n=5/69)(figure3). Ethnic group Indian had the highest incidence of UBT positive, 47.4% (n=18/38), followed by Others (Sikhs and foreigners) 42.8% (n=6/14), the Chinese 27.6% (n=45/163) and the Malays 11.6% (n= 16/138). UBT positive was the highest in the age group of 50 and above, 64.7% (n=55/85), followed by the age group between 30 to 49, 21.2% (n=18/85) and the age group of 29 and below, 14.5% (n=12/85). Out of the 85 UBT positive patients 91.8% (n=78/85)(figure4) of them responded to the conventional one week of triple therapy (PPI, amoxicillin, clarithromycin) with negative UBT at one-month post therapy compared to only 8.2% (n=7/85)(figure4) who failed with positive UBT at one-month post therapy.
  16. Preclinical Development of a Novel Epitope-based DNA Vaccine Candidate against SARS-CoV-2 and Evaluation of Immunogenicity in BALB/c Mice
    Khalid K, Lim HX, Anwar A, Tan SH, Hwang JS, Ong SK, et al.
    AAPS PharmSciTech, 2024 Mar 12;25(3):60.
    PMID: 38472523 DOI: 10.1208/s12249-024-02778-x
    The protective efficacies of current licensed vaccines against COVID-19 have significantly reduced as a result of SARS-CoV-2 variants of concern (VOCs) which carried multiple mutations in the Spike (S) protein. Considering that these vaccines were developed based on the S protein of the original SARS-CoV-2 Wuhan strain, we designed a recombinant plasmid DNA vaccine based on highly conserved and immunogenic B and T cell epitopes against SARS-CoV-2 Wuhan strain and the Omicron VOC. Literature mining and bioinformatics were used to identify 6 immunogenic peptides from conserved regions of the SARS-CoV-2 S and membrane (M) proteins. Nucleotide sequences encoding these peptides representing highly conserved B and T cell epitopes were cloned into a pVAX1 vector to form the pVAX1/S2-6EHGFP recombinant DNA plasmid vaccine. The DNA vaccine was intranasally or intramuscularly administered to BALB/c mice and evaluations of humoral and cellular immune responses were performed. The intramuscular administration of pVAX1/S2-6EHGFP was associated with a significantly higher percentage of CD8+ T cells expressing IFN-γ when compared with the empty vector and PBS controls. Intramuscular or intranasal administrations of pVAX1/S2-6EHGFP resulted in robust IgG antibody responses. Sera from mice intramuscularly immunized with pVAX1/S2-6EHGFP were found to elicit neutralizing antibodies capable of SARS-CoV-2 Omicron variant with the ACE2 cell surface receptor. This study demonstrated that the DNA vaccine construct encoding highly conserved immunogenic B and T cell epitopes was capable of eliciting potent humoral and cellular immune responses in mice.
  17. Anomalous aortic origin of a coronary artery (AAOCA): A case report
    Anwar A, Chan KMJ, Awang Y, Ping DC
    Med J Malaysia, 2019 Oct;74(5):436-438.
    PMID: 31649223
    Anomalous Aortic Origin of a Coronary Artery (AAOCA) is a rare anomaly of the coronary artery with a considerable risk of sudden cardiac death due to ischaemia of the heart. Symptoms may include chest pain on exertion, breathlessness or dizziness. We encountered a case of a 46- year-old female who complained of exertional chest pain with a positive-stress test and subsequently diagnosed with AAOCA through CT angiography (CTA). She successfully underwent a coronary artery bypass graft (CABG) surgery using a saphenous vein graft with uneventful recovery. Right internal mammary artery (RIMA) was not used as it was flimsy and the flow was very poor.
  18. Shaping a greener future: The role of geopolitical risk, renewable energy and financial development on environmental sustainability using the LCC hypothesis
    Wang W, Balsalobre-Lorente D, Anwar A, Adebayo TS, Cong PT, Quynh NN, et al.
    J Environ Manage, 2024 Apr;357:120708.
    PMID: 38552512 DOI: 10.1016/j.jenvman.2024.120708
    The recent progress report of Sustainable Development Goals (SDG) 2023 highlighted the extreme reactions of environmental degradation. This report also shows that the current efforts for achieving environmental sustainability (SDG 13) are inadequate and a comprehensive policy agenda is needed. However, the present literature has highlighted several determinants of environmental degradation but the influence of geopolitical risk on environmental quality (EQ) is relatively ignored. To fill this research gap and propose a inclusive policy structure for achieving the sustainable development goals. This study is the earliest attempt that delve into the effects o of geopolitical risk (GPR), financial development (FD), and renewable energy consumption (REC) on load capacity factor (LCF) under the framework of load capacity curve (LCC) hypothesis for selected Asian countries during 1990-2020. In this regard, we use several preliminary sensitivity tests to check the features and reliability of the dataset. Similarly, we use panel quantile regression for investigating long-run relationships. The factual results affirm the existence of the LCC hypothesis in selected Asian countries. Our findings also show that geopolitical risk reduces environmental quality whereas financial development and REC increase environmental quality. Drawing from the empirical findings, this study suggests a holistic policy approach for achieving the targets of SDG 13 (climate change).
  19. Fulltext Genome-wide analysis of copy number variation identifies candidate gene loci associated with the progression of non-alcoholic fatty liver disease
    Zain SM, Mohamed R, Cooper DN, Razali R, Rampal S, Mahadeva S, et al.
    PLoS One, 2014;9(4):e95604.
    PMID: 24743702 DOI: 10.1371/journal.pone.0095604
    Between 10 and 25% of individuals with non-alcoholic fatty liver disease (NAFLD) develop hepatic fibrosis leading to cirrhosis and hepatocellular carcinoma (HCC). To investigate the molecular basis of disease progression, we performed a genome-wide analysis of copy number variation (CNV) in a total of 49 patients with NAFLD [10 simple steatosis and 39 non-alcoholic steatohepatitis (NASH)] and 49 matched controls using high-density comparative genomic hybridization (CGH) microarrays. A total of 11 CNVs were found to be unique to individuals with simple steatosis, whilst 22 were common between simple steatosis and NASH, and 224 were unique to NASH. We postulated that these CNVs could be involved in the pathogenesis of NAFLD progression. After stringent filtering, we identified four rare and/or novel CNVs that may influence the pathogenesis of NASH. Two of these CNVs, located at 13q12.11 and 12q13.2 respectively, harbour the exportin 4 (XPO4) and phosphodiesterase 1B (PDE1B) genes which are already known to be involved in the etiology of liver cirrhosis and HCC. Cross-comparison of the genes located at these four CNV loci with genes already known to be associated with NAFLD yielded a set of genes associated with shared biological processes including cell death, the key process involved in 'second hit' hepatic injury. To our knowledge, this pilot study is the first to provide CNV information of potential relevance to the NAFLD spectrum. These data could prove invaluable in predicting patients at risk of developing NAFLD and more importantly, those who will subsequently progress to NASH.
  20. Identification and characterization of antibacterial compound(s) of cockroaches (Periplaneta americana)
    Ali SM, Siddiqui R, Ong SK, Shah MR, Anwar A, Heard PJ, et al.
    Appl Microbiol Biotechnol, 2017 Jan;101(1):253-286.
    PMID: 27743045 DOI: 10.1007/s00253-016-7872-2
    Infectious diseases remain a significant threat to human health, contributing to more than 17 million deaths, annually. With the worsening trends of drug resistance, there is a need for newer and more powerful antimicrobial agents. We hypothesized that animals living in polluted environments are potential sources of antimicrobials. Under polluted milieus, organisms such as cockroaches encounter different types of microbes, including superbugs. Such creatures survive the onslaught of superbugs and are able to ward off disease by producing antimicrobial substances. Here, we characterized antibacterial properties in extracts of various body organs of cockroaches (Periplaneta americana) and showed potent antibacterial activity in crude brain extract against methicillin-resistant Staphylococcus aureus and neuropathogenic Escherichia coli K1. The size-exclusion spin columns revealed that the active compound(s) are less than 10 kDa in molecular mass. Using cytotoxicity assays, it was observed that pre-treatment of bacteria with lysates inhibited bacteria-mediated host cell cytotoxicity. Using spectra obtained with LC-MS on Agilent 1290 infinity liquid chromatograph, coupled with an Agilent 6460 triple quadruple mass spectrometer, tissues lysates were analysed. Among hundreds of compounds, only a few homologous compounds were identified that contained the isoquinoline group, chromene derivatives, thiazine groups, imidazoles, pyrrole-containing analogs, sulfonamides, furanones, and flavanones and known to possess broad-spectrum antimicrobial properties and anti-inflammatory, anti-tumour, and analgesic properties. Further identification, characterization, and functional studies using individual compounds can act as a breakthrough in developing novel therapeutics against various pathogens including superbugs.
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