Displaying publications 581 - 600 of 616 in total

Abstract:
Sort:
  1. Ali EZ, Khalid MK, Yunus ZM, Yakob Y, Chin CB, Abd Latif K, et al.
    Eur J Pediatr, 2016 Mar;175(3):339-46.
    PMID: 26440671 DOI: 10.1007/s00431-015-2644-z
    Carbamoyl phosphate synthetase 1 (CPS1) deficiency is a rare autosomal recessive disorder of ureagenesis presenting as life-threatening hyperammonemia. In this study, we present the main clinical features and biochemical and molecular data of six Malaysian patients with CPS1 deficiency. All the patients have neonatal-onset symptoms, initially diagnosed as infections before hyperammonemia was recognized. They have typical biochemical findings of hyperglutaminemia, hypocitrullinemia, and low to normal urinary excretion of orotate. One neonate succumbed to the first hyperammonemic decompensation. Five neonatal survivors received long-term treatment consisting of dietary protein restriction and ammonia-scavenging drugs. They have delayed neurocognitive development of varying severity. Genetic analysis revealed eight mutations in CPS1 gene, five of which were not previously reported. Five mutations were missense changes while another three were predicted to create premature stop codons. In silico analyses showed that these new mutations affected different CPS1 enzyme domains and were predicted to interrupt interactions at enzyme active sites, disturb local enzyme conformation, and destabilize assembly of intact enzyme complex.

    CONCLUSION: All mutations are private except one mutation; p.Ile1254Phe was found in three unrelated families. Identification of a recurrent p.Ile1254Phe mutation suggests the presence of a common and unique mutation in our population. Our study also expands the mutational spectrum of the CPS1 gene.

    Matched MeSH terms: Computer Simulation
  2. Law WY, Asaruddin MR, Bhawani SA, Mohamad S
    BMC Res Notes, 2020 Nov 11;13(1):527.
    PMID: 33176880 DOI: 10.1186/s13104-020-05379-6
    OBJECTIVES: The aim of this study was to use Ligand-based pharmacophore modelling approach for four established antiviral drugs, namely remdesivir, lopinavir, ritonavir and hydroxychloroquine for COVID-19 inhibitors as training sets. In this study Twenty vanillin derivatives together with monolaurin and tetrodotoxin were used as test sets to evaluate as potential SARS-CoV-2 inhibitors. The Structure-based pharmacophore modelling approach was also performed using 5RE6, 5REX and 5RFZ in order to analyse the binding site and ligand-protein complex interactions.

    RESULTS: The pharmacophore modelling mode of 5RE6 displayed two Hydrogen Bond Acceptors (HBA) and one Hydrophobic (HY) interaction. Besides, the pharmacophore model of 5REX showed two HBA and two HY interactions. Finally, the pharmacophore model of 5RFZ showed three HBA and one HY interaction. Based on ligand-based approach, 20 Schiff-based vanillin derivatives, showed strong MPro inhibition activity. This was due to their good alignment and common features to PDB-5RE6. Similarly, monolaurin and tetrodotoxin displayed some significant activity against SARS-CoV-2. From structure-based approach, vanillin derivatives (1) to (12) displayed some potent MPro inhibition against SARS-CoV-2. Favipiravir, chloroquine and hydroxychloroquine also showed some significant MPro inhibition.

    Matched MeSH terms: Computer Simulation
  3. Alizadeh M, Kadir MR, Fadhli MM, Fallahiarezoodar A, Azmi B, Murali MR, et al.
    J Orthop Res, 2013 Sep;31(9):1447-54.
    PMID: 23640802 DOI: 10.1002/jor.22376
    Posterior instrumentation is a common fixation method used to treat thoracolumbar burst fractures. However, the role of different cross-link configurations in improving fixation stability in these fractures has not been established. A 3D finite element model of T11-L3 was used to investigate the biomechanical behavior of short (2 level) and long (4 level) segmental spine pedicle screw fixation with various cross-links to treat a hypothetical L1 vertebra burst fracture. Three types of cross-link configurations with an applied moment of 7.5 Nm and 200 N axial force were evaluated. The long construct was stiffer than the short construct irrespective of whether the cross-links were used (p < 0.05). The short constructs showed no significant differences between the cross-link configurations. The XL cross-link provided the highest stiffness and was 14.9% stiffer than the one without a cross-link. The long construct resulted in reduced stress to the adjacent vertebral bodies and screw necks, with 66.7% reduction in bending stress on L2 when the XL cross-link was used. Thus, the stability for L1 burst fracture fixation was best achieved by using long segmental posterior instrumentation constructs and an XL cross-link configuration. Cross-links did not improved stability when a short structure was used.
    Matched MeSH terms: Computer Simulation
  4. Basri AA, Zuber M, Basri EI, Zakaria MS, Aziz AFA, Tamagawa M, et al.
    Comput Math Methods Med, 2020;2020:9163085.
    PMID: 32454886 DOI: 10.1155/2020/9163085
    This study investigated the impact of paravalvular leakage (PVL) in relation to the different valve openings of the transcatheter aortic valve implantation (TAVI) valve using the fluid structure interaction (FSI) approach. Limited studies were found on the subject of FSI with regards to TAVI-PVL condition, which involves both fluid and structural responses in coupling interaction. Hence, further FSI simulation with the two-way coupling method is implemented to investigate the effects of hemodynamics blood flow along the patient-specific aorta model subjected to the interrelationship between PVL and the different valve openings using the established FSI software ANSYS 16.1. A 3D patient-specific aorta model is constructed using MIMICS software. The TAVI valve identical to Edward SAPIEN XT 26 (Edwards Lifesciences, Irvine, California), at different Geometrical Orifice Areas (GOAs), is implanted into the patient's aortic annulus. The leaflet opening of the TAVI valve is drawn according to severity of GOA opening represented in terms of 100%, 80%, 60%, and 40% opening, respectively. The result proved that the smallest percentage of GOA opening produced the highest possibility of PVL, increased the recirculatory flow proximally to the inner wall of the ascending aorta, and produced lower backflow velocity streamlines through the side area of PVL region. Overall, 40% GOA produced 89.17% increment of maximum velocity magnitude, 19.97% of pressure drop, 65.70% of maximum WSS magnitude, and a decrement of 33.62% total displacement magnitude with respect to the 100% GOA.
    Matched MeSH terms: Computer Simulation
  5. Ashraf A, Mudgil P, Palakkott A, Iratni R, Gan CY, Maqsood S, et al.
    J Dairy Sci, 2021 Jan;104(1):61-77.
    PMID: 33162074 DOI: 10.3168/jds.2020-18627
    The molecular basis of the anti-diabetic properties of camel milk reported in many studies and the exact active agent are still elusive. Recent studies have reported effects of camel whey proteins (CWP) and their hydrolysates (CWPH) on the activities of dipeptidyl peptidase IV (DPP-IV) and the human insulin receptor (hIR). In this study, CWPH were generated, screened for DPP-IV binding in silico and inhibitory activity in vitro, and processed for peptide identification. Furthermore, pharmacological action of intact CWP and their selected hydrolysates on hIR activity and signaling and on glucose uptake were investigated in cell lines. Results showed inhibition of DPP-IV by CWP and CWPH and their positive action on hIR activation and glucose uptake. Interestingly, the combination of CWP or CWPH with insulin revealed a positive allosteric modulation of hIR that was drastically reduced by the competitive hIR antagonist. Our data reveal for the first time the profiling and pharmacological actions of CWP and their derived peptides fractions on hIR and their pathways involved in glucose homeostasis. This sheds more light on the anti-diabetic properties of camel milk by providing the molecular basis for the potential use of camel milk in the management of diabetes.
    Matched MeSH terms: Computer Simulation
  6. Mohd Faudzi SM, Leong SW, Auwal FA, Abas F, Wai LK, Ahmad S, et al.
    Arch Pharm (Weinheim), 2021 Jan;354(1):e2000161.
    PMID: 32886410 DOI: 10.1002/ardp.202000161
    A new series of pyrazole, phenylpyrazole, and pyrazoline analogs of diarylpentanoids (excluding compounds 3a, 4a, 5a, and 5b) was pan-assay interference compounds-filtered and synthesized via the reaction of diarylpentanoids with hydrazine monohydrate and phenylhydrazine. Each analog was evaluated for its anti-inflammatory ability via the suppression of nitric oxide (NO) on IFN-γ/LPS-activated RAW264.7 macrophage cells. The compounds were also investigated for their inhibitory capability toward acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), using a modification of Ellman's spectrophotometric method. The most potent NO inhibitor was found to be phenylpyrazole analog 4c, followed by 4e, when compared with curcumin. In contrast, pyrazole 3a and pyrazoline 5a were found to be the most selective and effective BChE inhibitors over AChE. The data collected from the single-crystal X-ray diffraction analysis of compound 5a were then applied in a docking simulation to determine the potential binding interactions that were responsible for the anti-BChE activity. The results obtained signify the potential of these pyrazole and pyrazoline scaffolds to be developed as therapeutic agents against inflammatory conditions and Alzheimer's disease.
    Matched MeSH terms: Computer Simulation
  7. Saddique FA, Aslam S, Ahmad M, Ashfaq UA, Muddassar M, Sultan S, et al.
    Molecules, 2021 May 20;26(10).
    PMID: 34065194 DOI: 10.3390/molecules26103043
    Diabetes mellitus (DM) is a chronic disorder and has affected a large number of people worldwide. Insufficient insulin production causes an increase in blood glucose level that results in DM. To lower the blood glucose level, various drugs are employed that block the activity of the α-glucosidase enzyme, which is considered responsible for the breakdown of polysaccharides into monosaccharides leading to an increase in the intestinal blood glucose level. We have synthesized novel 2-(3-(benzoyl/4-bromobenzoyl)-4-hydroxy-1,1-dioxido-2H-benzo[e][1,2]thiazin-2-yl)-N-arylacetamides and have screened them for their in silico and in vitro α-glucosidase inhibition activity. The derivatives 11c, 12a, 12d, 12e, and 12g emerged as potent inhibitors of the α-glucosidase enzyme. These compounds exhibited good docking scores and excellent binding interactions with the selected residues (Asp203, Asp542, Asp327, His600, Arg526) during in silico screening. Similarly, these compounds also showed good in vitro α-glucosidase inhibitions with IC50 values of 30.65, 18.25, 20.76, 35.14, and 24.24 μM, respectively, which were better than the standard drug, acarbose (IC50 = 58.8 μM). Furthermore, a good agreement was observed between in silico and in vitro modes of study.
    Matched MeSH terms: Computer Simulation
  8. Zhang L, Feng XK, Ng YK, Li SC
    BMC Genomics, 2016 Aug 18;17 Suppl 4:430.
    PMID: 27556418 DOI: 10.1186/s12864-016-2791-2
    BACKGROUND: Accurately identifying gene regulatory network is an important task in understanding in vivo biological activities. The inference of such networks is often accomplished through the use of gene expression data. Many methods have been developed to evaluate gene expression dependencies between transcription factor and its target genes, and some methods also eliminate transitive interactions. The regulatory (or edge) direction is undetermined if the target gene is also a transcription factor. Some methods predict the regulatory directions in the gene regulatory networks by locating the eQTL single nucleotide polymorphism, or by observing the gene expression changes when knocking out/down the candidate transcript factors; regrettably, these additional data are usually unavailable, especially for the samples deriving from human tissues.

    RESULTS: In this study, we propose the Context Based Dependency Network (CBDN), a method that is able to infer gene regulatory networks with the regulatory directions from gene expression data only. To determine the regulatory direction, CBDN computes the influence of source to target by evaluating the magnitude changes of expression dependencies between the target gene and the others with conditioning on the source gene. CBDN extends the data processing inequality by involving the dependency direction to distinguish between direct and transitive relationship between genes. We also define two types of important regulators which can influence a majority of the genes in the network directly or indirectly. CBDN can detect both of these two types of important regulators by averaging the influence functions of candidate regulator to the other genes. In our experiments with simulated and real data, even with the regulatory direction taken into account, CBDN outperforms the state-of-the-art approaches for inferring gene regulatory network. CBDN identifies the important regulators in the predicted network: 1. TYROBP influences a batch of genes that are related to Alzheimer's disease; 2. ZNF329 and RB1 significantly regulate those 'mesenchymal' gene expression signature genes for brain tumors.

    CONCLUSION: By merely leveraging gene expression data, CBDN can efficiently infer the existence of gene-gene interactions as well as their regulatory directions. The constructed networks are helpful in the identification of important regulators for complex diseases.

    Matched MeSH terms: Computer Simulation
  9. Badhan R, Zakaria Z, Olafuyi O
    J Pharm Sci, 2018 08;107(8):2236-2250.
    PMID: 29626533 DOI: 10.1016/j.xphs.2018.03.026
    Ivermectin has demonstrated many successes in the treatment of a range of nematode infections. Considering the increase in malaria resistance, attention has turned toward ivermectin as a candidate for repurposing for malaria. This study developed and validated an ivermectin physiology-based pharmacokinetic model in healthy adults (20-50 years), pediatric (3-5 years/15-25 kg) subjects, and a representative adult malaria population group (Thailand). Dosing optimization demonstrating a twice-daily dose for 3- or 5-day regimens would provide a time above the LC50 of more than 7 days for adult and pediatric subjects. Furthermore, to address the occurrence of CYP450 induction that is often encountered with antiretroviral agents, simulated drug-drug interaction studies with efavirenz highlighted that a 1-mg/kg once-daily dose for 5 days would counteract the increased ivermectin hepatic clearance and enable a time above LC50 of 138.8 h in adults and 141.2 h in pediatric subjects. It was also demonstrated that dosage regimen design would require consideration of the age-weight geographical relationship of the subjects, with a dosage regimen for a representative Thailand population group requiring at least a single daily dose for 5 days to maintain ivermectin plasma concentrations and a time above LC50 similar to that in healthy adults.
    Matched MeSH terms: Computer Simulation
  10. Abd Rahman AN, Tett SE, Abdul Gafor HA, McWhinney BC, Staatz CE
    Eur J Drug Metab Pharmacokinet, 2017 Dec;42(6):993-1004.
    PMID: 28536776 DOI: 10.1007/s13318-017-0420-3
    BACKGROUND AND OBJECTIVE: Mycophenolic acid (MPA) provides effective treatment for lupus nephritis patients. Owing to its large pharmacokinetic variability, it is questionable whether standard fixed dose therapy can achieve optimal MPA exposure. The aim of this study was to develop a population pharmacokinetic model of MPA and its metabolite, 7-O-MPA-β-glucuronide (MPAG), to identify important covariate influences and better predict patient dosing requirements.
    METHODS: MPA and MPAG concentration-time profiles were collected from 25 patients receiving mycophenolate mofetil (MMF) with or without cyclosporine (CsA) co-therapy. Samples were collected pre-dose and at 1, 2, 4, 6 and 8 h post-dose on one or two occasions.
    RESULTS: A total of 225 and 226 concentration-time measurements of MPA and MPAG, respectively, were used to develop the model, utilizing NONMEM® software. A two-compartment model with first-order absorption and elimination for MPA and a one-compartment model with first-order elimination and enterohepatic circulation (EHC) for MPAG best described the data. Apparent clearance of MPAG (CL/F MPAG) significantly decreased with reducing renal function and extent of EHC was reduced with concomitant CsA use. Simulations using the final model showed that a 70-kg subject with a creatinine clearance of 90 mL/min receiving concomitant CsA would require 1.25 g of MMF twice daily while a similar subject who did not receive concomitant CsA would require 0.75 g twice daily to achieve a MPA area under the concentration-time curve from 0 to 12 h (AUC0-12) of 45 mg·h/L.
    CONCLUSION: A 'tiered' dosing approach considering patient renal function and CsA co-therapy, rather than a 'one dose fits all' approach, would help individualize MMF therapy in adult lupus nephritis patients to ensure more patients have optimal MPA exposure.
    Study site: Nephrology and Systemic Lupus Erythematosus (SLE) Clinics, Pusat Perubatan Universiti Kebangsaan Malaysia (PPUKM), Kuala Lumpur, Malaysia
    Matched MeSH terms: Computer Simulation
  11. Yap E, Norziha ZA, Simbun A, Tumian NR, Cheong SK, Leong CF, et al.
    Leuk. Res., 2017 08;59:32-40.
    PMID: 28544907 DOI: 10.1016/j.leukres.2017.05.015
    Chronic myeloid leukemia (CML) patients who do not achieve landmark responses following treatment with imatinib mesylate (IM) are considered IM-resistant. Although IM-resistance can be due to BCR-ABL kinase domain (KD) mutations, many IM-resistant patients do not have detectable BCR-ABL KD mutations. MicroRNAs (miRNAs) are short non-coding RNAs that control gene expression. To investigate the role of miRNAs in IM-resistance, we recruited 8 chronic phase CML patients with IM-resistance who tested negative for BCR-ABL KD mutations and 2 healthy normal controls. Using miRNA sequencing, we identified 54 differentially expressed miRNAs; 43 of them downregulated. The 3 most differentially downregulated miRNAs were miR-146a-5p, miR-99b-5p and miR-151a-5p. Using real-time quantitative reverse transcriptase-polymerase chain reaction, the expression patterns of the 3 miRNAs were validated on the same cohort of 8 patients in addition to 3 other IM-resistant CML patients. In-silico analysis showed that the predicted gene targets are ATRIP, ATR, WDR48, RAD51C and FANCA genes which are involved in the Fanconi Anemia/BRCA pathway. This pathway regulates DNA damage response (DDR) and influences disease response to chemotherapy. Thus it is conceivable that DDR constitutes a key component in IM-resistance. Further research is needed to elucidate miRNA modulation of the predicted gene targets.
    Matched MeSH terms: Computer Simulation
  12. KishanRaj S, Sumitha S, Siventhiran B, Thiviyaa O, Sathasivam KV, Xavier R, et al.
    Mol Biol Rep, 2018 Dec;45(6):2333-2343.
    PMID: 30284142 DOI: 10.1007/s11033-018-4397-z
    Proteus mirabilis, a gram-negative bacterium of the family Enterobacteriaceae, is a leading cause of urinary tract infection (UTI) with rapid development of multi-drug resistance. Identification of small regulatory RNAs (sRNAs), which belongs to a class of RNAs that do not translate into a protein, could permit the comprehension of the regulatory roles this molecules play in mediating pathogenesis and multi-drug resistance of the organism. In this study, comparative sRNA analysis across three different members of Enterobacteriaceae (Escherichia coli, Salmonella typhi and Salmonella typhimurium) was carried out to identify the sRNA homologs in P. mirabilis. A total of 232 sRNA genes that were reported in E. coli, S. typhi and S. typhimurium were subjected to comparative analysis against P. mirabilis HI4320 genome. We report the detection of 14 sRNA candidates, conserved in the orthologous regions of P. mirabilis, that are not included in Rfam database. Northern-blot analysis was carried out for selected three sRNA candidates from the current investigation and three known sRNA from Rfam of P. mirabilis. The expression pattern of the six sRNA candidates shows that they are growth stage-dependant. To the best of our knowledge, this is the first report on the identification of sRNA candidates in P. mirabilis.
    Matched MeSH terms: Computer Simulation
  13. Looi D, Goh BH, Khan SU, Ahemad N, Palanisamy UD
    Int J Food Sci Nutr, 2021 Jun;72(4):470-477.
    PMID: 33032478 DOI: 10.1080/09637486.2020.1830263
    Hypertension is defined as the persistence of elevated blood pressure in the circulation system. The renin-angiotensin-aldosterone system is a major modulator of blood pressure. Among the risk factors of cardiovascular disease, hypertension is the most preventable and treatable, with drugs such as ACE inhibitors. Many ACE inhibitors are known to have undesirable side effects and hence, natural alternatives are being sought. Dietary polyphenols, particularly ellagitannins, are derived from plant products and are known to exhibit a variety of bioactivities. Geraniin, an ellagitannin has been shown to have antihypertensive activity in animal experiments. It is speculated that the metabolites of geraniin are responsible for its ACE inhibitory activity. We have performed in vitro ACE inhibition and in silico studies with geraniin and its metabolites (ellagic acid, urolithins). Our studies confirm that ellagic acid exhibited similar inhibitory potential to ACE as the positive control captopril.
    Matched MeSH terms: Computer Simulation
  14. Kaboli PJ, Bazrafkan M, Ismail P, Ling KH
    Recent Pat Anticancer Drug Discov, 2017 Nov 20;12(4):384-400.
    PMID: 28969581 DOI: 10.2174/1574892812666170929131247
    BACKGROUND: Protoberberine isoquinoline alkaloids are found in many plant species. They consist of a diverse class of secondary metabolites with many pharmacologically active members, such as different derivatives of berberine already patented. In the development of approximately 20-25% of all cancers, altered hedgehog (Hh) signalling is involved where the smoothened (Smo) transmembrane receptor triggers Hh signalling pathway towards Gli1 gene expression.

    OBJECTIVE: The current study aimed to model and verify the anti-Smo activity of berberine and its derivatives using a novel automated script.

    METHOD: Based on the patented inventions filed on ADMET modelling until 2016, which also predicts ADMET parameters and binding efficiency indices for all molecules, a script was developed to run automated molecular docking for a large number of small molecules.

    RESULTS: Berberine was found to interact with Lys395 of Smo receptor via hydrogen bonding and cation-π interactions. In addition, π-π interactions between berberine aromatic rings and two aromatic residues in the Smo transmembrane domain, Tyr394 and Phe484, were noted. Binding efficiency indices using an in silico approach to plot the Smo-specific binding potency of each ligand was performed. The mRNA level of Gli1 was studied as the outcome of Hh signalling pathway to show the effect of berberine on hedgehog signalling.

    CONCLUSION: This study predicted the role of berberine as an inhibitor of Smo receptor, suggesting its effectiveness in hedgehog signalling during cancer treatment.

    Matched MeSH terms: Computer Simulation
  15. Salar U, Khan KM, Chigurupati S, Taha M, Wadood A, Vijayabalan S, et al.
    Sci Rep, 2017 12 05;7(1):16980.
    PMID: 29209017 DOI: 10.1038/s41598-017-17261-w
    Current research is based on the identification of novel inhibitors of α-amylase enzyme. For that purpose, new hybrid molecules of hydrazinyl thiazole substituted chromones 5-27 were synthesized by multi-step reaction and fully characterized by various spectroscopic techniques such as EI-MS, HREI-MS, 1H-NMR and 13C-NMR. Stereochemistry of the iminic bond was confirmed by NOESY analysis of a representative molecule. All compounds 5-27 along with their intervening intermediates 1-4, were screened for in vitro α-amylase inhibitory, DPPH and ABTS radical scavenging activities. All compounds showed good inhibition potential in the range of IC50 = 2.186-3.405 µM as compared to standard acarbose having IC50 value of 1.9 ± 0.07 µM. It is worth mentioning that compounds were also demonstrated good DPPH (IC50 = 0.09-2.233 µM) and ABTS (IC50 = 0.584-3.738 µM) radical scavenging activities as compared to standard ascorbic acid having IC50 = 0.33 ± 0.18 µM for DPPH and IC50 = 0.53 ± 0.3 µM for ABTS radical scavenging activities. In addition to that cytotoxicity of the compounds were checked on NIH-3T3 mouse fibroblast cell line and found to be non-toxic. In silico studies were performed to rationalize the binding mode of compounds (ligands) with the active site of α-amylase enzyme.
    Matched MeSH terms: Computer Simulation
  16. Herman LS, Fornace K, Phelan J, Grigg MJ, Anstey NM, William T, et al.
    PLoS Negl Trop Dis, 2018 Jun;12(6):e0006457.
    PMID: 29902183 DOI: 10.1371/journal.pntd.0006457
    BACKGROUND: Plasmodium knowlesi is the most common cause of malaria in Malaysian Borneo, with reporting limited to clinical cases presenting to health facilities and scarce data on the true extent of transmission. Serological estimations of transmission have been used with other malaria species to garner information about epidemiological patterns. However, there are a distinct lack of suitable serosurveillance tools for this neglected disease.

    METHODOLOGY/PRINCIPAL FINDINGS: Using in silico tools, we designed and expressed four novel P. knowlesi protein products to address the distinct lack of suitable serosurveillance tools: PkSERA3 antigens 1 and 2, PkSSP2/TRAP and PkTSERA2 antigen 1. Antibody prevalence to these antigens was determined by ELISA for three time-points post-treatment from a hospital-based clinical treatment trial in Sabah, East Malaysia (n = 97 individuals; 241 total samples for all time points). Higher responses were observed for the PkSERA3 antigen 2 (67%, 65/97) across all time-points (day 0: 36.9% 34/92; day 7: 63.8% 46/72; day 28: 58.4% 45/77) with significant differences between the clinical cases and controls (n = 55, mean plus 3 SD) (day 0 p<0.0001; day 7 p<0.0001; day 28 p<0.0001). Using boosted regression trees, we developed models to classify P. knowlesi exposure (cross-validated AUC 88.9%; IQR 86.1-91.3%) and identified the most predictive antibody responses.

    CONCLUSIONS/SIGNIFICANCE: The PkSERA3 antigen 2 had the highest relative variable importance in all models. Further validation of these antigens is underway to determine the specificity of these tools in the context of multi-species infections at the population level.

    Matched MeSH terms: Computer Simulation
  17. Rahman HS, Tan BL, Othman HH, Chartrand MS, Pathak Y, Mohan S, et al.
    Biomed Res Int, 2020;2020:8857428.
    PMID: 33381591 DOI: 10.1155/2020/8857428
    Angiogenesis is a crucial area in scientific research because it involves many important physiological and pathological processes. Indeed, angiogenesis is critical for normal physiological processes, including wound healing and embryonic development, as well as being a component of many disorders, such as rheumatoid arthritis, obesity, and diabetic retinopathies. Investigations of angiogenic mechanisms require assays that can activate the critical steps of angiogenesis as well as provide a tool for assessing the efficacy of therapeutic agents. Thus, angiogenesis assays are key tools for studying the mechanisms of angiogenesis and identifying the potential therapeutic strategies to modulate neovascularization. However, the regulation of angiogenesis is highly complex and not fully understood. Difficulties in assessing the regulators of angiogenic response have necessitated the development of an alternative approach. In this paper, we review the standard models for the study of tumor angiogenesis on the macroscopic scale that include in vitro, in vivo, and computational models. We also highlight the differences in several modeling approaches and describe key advances in understanding the computational models that contributed to the knowledge base of the field.
    Matched MeSH terms: Computer Simulation
  18. Tang JR, Mat Isa NA, Ch'ng ES
    PLoS One, 2015;10(11):e0142830.
    PMID: 26560331 DOI: 10.1371/journal.pone.0142830
    Despite the effectiveness of Pap-smear test in reducing the mortality rate due to cervical cancer, the criteria of the reporting standard of the Pap-smear test are mostly qualitative in nature. This study addresses the issue on how to define the criteria in a more quantitative and definite term. A negative Pap-smear test result, i.e. negative for intraepithelial lesion or malignancy (NILM), is qualitatively defined to have evenly distributed, finely granular chromatin in the nuclei of cervical squamous cells. To quantify this chromatin pattern, this study employed Fuzzy C-Means clustering as the segmentation technique, enabling different degrees of chromatin segmentation to be performed on sample images of non-neoplastic squamous cells. From the simulation results, a model representing the chromatin distribution of non-neoplastic cervical squamous cell is constructed with the following quantitative characteristics: at the best representative sensitivity level 4 based on statistical analysis and human experts' feedbacks, a nucleus of non-neoplastic squamous cell has an average of 67 chromatins with a total area of 10.827 μm2; the average distance between the nearest chromatin pair is 0.508 μm and the average eccentricity of the chromatin is 0.47.
    Matched MeSH terms: Computer Simulation
  19. Michailidou K, Lindström S, Dennis J, Beesley J, Hui S, Kar S, et al.
    Nature, 2017 Nov 02;551(7678):92-94.
    PMID: 29059683 DOI: 10.1038/nature24284
    Breast cancer risk is influenced by rare coding variants in susceptibility genes, such as BRCA1, and many common, mostly non-coding variants. However, much of the genetic contribution to breast cancer risk remains unknown. Here we report the results of a genome-wide association study of breast cancer in 122,977 cases and 105,974 controls of European ancestry and 14,068 cases and 13,104 controls of East Asian ancestry. We identified 65 new loci that are associated with overall breast cancer risk at P 
    Matched MeSH terms: Computer Simulation
  20. Ramasamy S, Chin SP, Sukumaran SD, Buckle MJ, Kiew LV, Chung LY
    PLoS One, 2015;10(5):e0126565.
    PMID: 25965066 DOI: 10.1371/journal.pone.0126565
    Bacopa monnieri has been used in Ayurvedic medicine to improve memory and cognition. The active constituent responsible for its pharmacological effects is bacoside A, a mixture of dammarane-type triterpenoid saponins containing sugar chains linked to a steroid aglycone skeleton. Triterpenoid saponins have been reported to be transformed in vivo to metabolites that give better biological activity and pharmacokinetic characteristics. Thus, the activities of the parent compounds (bacosides), aglycones (jujubogenin and pseudojujubogenin) and their derivatives (ebelin lactone and bacogenin A1) were compared using a combination of in silico and in vitro screening methods. The compounds were docked into 5-HT1A, 5-HT2A, D1, D2, M1 receptors and acetylcholinesterase (AChE) using AutoDock and their central nervous system (CNS) drug-like properties were determined using Discovery Studio molecular properties and ADMET descriptors. The compounds were screened in vitro using radioligand receptor binding and AChE inhibition assays. In silico studies showed that the parent bacosides were not able to dock into the chosen CNS targets and had poor molecular properties as a CNS drug. In contrast, the aglycones and their derivatives showed better binding affinity and good CNS drug-like properties, were well absorbed through the intestines and had good blood brain barrier (BBB) penetration. Among the compounds tested in vitro, ebelin lactone showed binding affinity towards M1 (Ki = 0.45 μM) and 5-HT2A (4.21 μM) receptors. Bacoside A and bacopaside X (9.06 μM) showed binding affinity towards the D1 receptor. None of the compounds showed any inhibitory activity against AChE. Since the stimulation of M1 and 5-HT2A receptors has been implicated in memory and cognition and ebelin lactone was shown to have the strongest binding energy, highest BBB penetration and binding affinity towards M1 and 5-HT2A receptors, we suggest that B. monnieri constituents may be transformed in vivo to the active form before exerting their pharmacological activity.
    Matched MeSH terms: Computer Simulation
Filters
Contact Us

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links