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Synthesis of γ-N-modified 8-oxo-2’-deoxyguanosine triphosphate and its characterization
No full text8-OxodGTP is generated by the reaction between dGTP and reactive oxygen species and a considered mutagenic nucleotide. It can be incorporated into the duplex DNA during replication processes by the DNA polymerase, and thus the repair enzyme removes oxodGTP from the nucleotide pools in living cells. On the other hand, the γ-modified triphosphates show interesting properties for use as biological tools. Therefore, the γ-N-pyrenylalkyl-oxodGTP derivatives were synthesized and their effect on the enzymatic reactions were evaluated. The γ-N-pyrenylmethyl-oxodGTP was found to be accepted by the DNA polymerase just like oxodGTP, but showed a competitive inhibition property for the human oxodGTPase. © 2019, © 2019 Taylor & Francis Group, LLC
Highly Sensitive and Selective Ethanol Sensor Based on ZnO Nanorod on SnO2 Thin Film Fabricated by Spray Pyrolysis
No full textThis work reports the fabrication of mixed structure of ZnO nanorod on SnO2 thin film via spray pyrolysis followed by thermal annealing and their gas sensing properties. ZnO/SnO2 nanostructures are successfully prepared on a gold interdigitated alumina substrate by spraying varying mixed precursor concentrations of zinc acetate and tin (IV) chloride pentahydrate solutions in ethanol and thermal annealing. The morphology of the nanostructures is controlled by tailoring the Zn:Sn ratio in the precursor solution mixture. Unique ZnO crystals and ZnO nanorods are observed under a field emission scanning electron microscopy (FESEM) when the Zn/Sn ratio in the precursor solution is in between 13:7 and 17:3 after thermal annealing. The fabricated nanostructures are tested for ethanol, methane and hydrogen in air ambient for various gas concentrations ranging from 25 to 400 ppm and the effect of fabrication conditions on the sensitivity and selectivity are studied. Among the nanostructure sensors studied, the film fabricated with molar ratio of Zn/Sn =3:1 shows better sensitivity and selectivity to ethanol due to high sensing surface area of the nanorod. The response to 25 ppm ethanol is found to be as high as 50 at an operating temperature of 400°C. © 2019 Tharsika, Thanihaichelvan, Haseeb and Akbar
Linkage analysis and whole exome sequencing reveals AHNAK2 as a novel genetic cause for autosomal recessive CMT in a Malaysian family
No full textCharcot-Marie-Tooth (CMT) disease is a form of inherited peripheral neuropathy that affects motor and sensory neurons. To identify the causative gene in a consanguineous family with autosomal recessive CMT (AR-CMT), we employed a combination of linkage analysis and whole exome sequencing. After excluding known AR-CMT genes, genome-wide linkage analysis mapped the disease locus to a 7.48-Mb interval on chromosome 14q32.11–q32.33, flanked by the markers rs2124843 and rs4983409. Whole exome sequencing identified two non-synonymous variants (p.T40P and p.H915Y) in the AHNAK2 gene that segregated with the disease in the family. Pathogenic predictions indicated that p.T40P is the likely causative allele. Analysis of AHNAK2 expression in the AR-CMT patient fibroblasts showed significantly reduced mRNA and protein levels. AHNAK2 binds directly to periaxin which is encoded by the PRX gene, and PRX mutations are associated with another form of AR-CMT (CMT4F). The altered expression of mutant AHNAK2 may disrupt the AHNAK2-PRX interaction in which one of its known functions is to regulate myelination. © 2019, Springer-Verlag GmbH Germany, part of Springer Nature
Evaluating Physicians’ Intention to Discriminate Against Patients Living with HIV in Malaysia
No full textPeople with HIV (PWH) in Malaysia experience high levels of stigma, which may act as a barrier to accessing healthcare. Stigma against PWH in medical settings is understudied in Malaysia. In the present study, we examine factors associated with physicians’ intention to discriminate against PWH in Malaysia. A cross-sectional online survey was emailed to all 1431 physicians at two major university hospitals in Malaysia; 568 (39.6%) participants completed the survey and were included in this analysis. Measures included intention to discriminate against PWH, stigma-related constructs, and socio-demographic characteristics. Multivariate linear regression was used to identify factors associated with intention to discriminate against PWH. Participants were comprised of women (53.5%), Malays (43.1%), and Chinese (35.0%) with nearly 10 years of clinical experience. Most participants were from non-surgical specialties (77.6%). The final multivariate linear regression showed that physicians who expressed greater discriminatory intent against PWH also expressed more negative feelings toward PWH, more HIV-related shame, were more fearful of HIV, and believed that PWH do not deserve good care. Physicians from surgical-based specialties were also significantly more likely to endorse discriminatory intent toward PWH. Stigma and intentions to discriminate against a class of patients, including PWH, can undermine engagement in care, which is central to international HIV prevention and treatment strategies. Interventions that reduce stigma toward PWH among physicians are crucial to ensuring equitable and stigma-free healthcare. © 2018, Springer Science+Business Media, LLC, part of Springer Nature
Framework for technical communication skills content development for students in malaysian vocational colleges: A fuzzy delphi study
No full textDeveloping technical communication is vital to ensure employability of graduates in Technical and Vocational Education and Training (TVET) institutions. However, limited studies are available to guide its development in Malaysian Vocational Colleges. Hence, this study is aimed at proposing a framework for technical communication development for effective implementation in Malaysian Vocational Colleges. This study employs Fuzzy Delphi Method (FDM) with 17 experts from industry and TVET institutions in identifying the prominent content of learning for technical communication skills development of students in Malaysian Vocational Colleges. Generally, the findings suggest that all clusters of technical communication skills (oral technical, written technical, interpersonal and researching skills) are important to be emphasised as the content of learning, with a high percentage of agreement (>75%). However, a number of items under Content of Learning components were omitted. For instance, two items under Oral Technical Communication, eight items under Written Technical Communication, two items under Interpersonal and one item under Researching Skills achieved percentage of agreement below 75%. The proposed framework is a relevant reference in introducing technical communication in Malaysian Vocational Colleges. © 2019, Penerbit UTHM. All rights reserved
[Corrigendum] Antiproliferative effects of imatinib mesylate on ZR‑75‑1 and MDA‑MB‑231 cell lines via PDGFR‑β, PDGF‑BB, c‑Kit and SCF expression
No full textAn interested reader drew to our attention that the above study appeared to contain a high level of overlap with an article by the same authors published in the journal Drug Design, Development and Therapy [Kadivar A, Kamalidehghan B, Akbari Javar H, Karimi B, Sedghi R and Noordin MI: Antiproliferation effect of imatinib mesylate on MCF7, T‑47D tumorigenic and MCF 10A nontumorigenic breast cell lines via PDGFR‑β, PDGF‑BB, c‑Kit and SCF genes. Drug Des Devel Ther 11: 469‑481, 2017]. Following an internal investigation and also in liaison with the authors, it was established that, although the studies were conducted along broadly similar lines, the papers contained entirely different data involving two different subsets of cell lines; the submission to Drug Des Devel Ther aimed to explore the effects of imatinib mesylate on three different groups, with each group being represented by a cell line, whereas the submission to Int J Mol Med explored the effectiveness of imatinib mesylate in breast cancer cell lines. In spite of this, considering the relatedness of the articles and the fact that the paper to Drug Des Devel Ther was submitted first and published while the Int J Mol Med paper was passing through the peer‑review process, the authors concede that they should have properly referenced their paper submitted to Drug Des Devel Ther in the Int J Mol Med paper. Note that the publishers of Drug Des Devel Ther, with whom we were liaising, agreed with the decision to issue a Corrigendum for this paper that acknowledges the article published in Drug Des Devel Ther. The authors regret their failure to acknowledge the related paper in this instance, and apologize to the readership for this oversight. [the original article was published in International Journal of Molecular Medicine 14: 414‑424, 2018; DOI: 10.3892/ijmm.2018.3590]
Diagnosing Metabolic Syndrome Using Genetically Optimised Bayesian ARTMAP
No full textMetabolic Syndrome (MetS) constitutes of metabolic abnormalities that lead to non-communicable diseases, such as type II diabetes, cardiovascular diseases, and cancer. Early and accurate diagnosis of this abnormality is required to prevent its further progression to these diseases. This paper aims to diagnose the risk of MetS using a new non-clinical approach called 'genetically optimized Bayesian adaptive resonance theory mapping' (GOBAM). We evolve the Bayesian adaptive resonance theory mapping (BAM) by using genetic algorithm to optimize the parameters of BAM and its training input sequence. We use the GOBAM algorithm to classify individuals as either being at risk of MetS or not at risk of MetS with a related posterior probability, which ranges between 0 and 1. A data set of 11 237 Malaysians from the CLUSTer study stratified by age and gender into four subcategories was used to evaluate the proposed GOBAM algorithm. The comparative evaluation of our results suggested that the GOBAM performs significantly better than other classical adaptive resonance theory mapping models on the area under the receiver operating characteristic curves (AUC) and others criteria. Our algorithm gives an AUC of 86.42 %, 87.04 %, 91.08 %, and 89.24 % for the young female, middle aged female, young male, and middle-aged male subcategories, respectively. The proposed model can be used to support medical practitioners in accurate and early diagnosis of MetS. © 2013 IEEE
Solid-liquid extraction of bioactive compounds with antioxidant potential from Alternanthera sesillis (red) and identification of the polyphenols using UHPLC-QqQ-MS/MS
No full textAlternanthera sessilis (red) (ASR) is an edible herbal plant with many beneficial health effects. This study aimed to investigate the antioxidant components and antioxidant activities of the edible leaves and stems of ASR extracted using solvent of varying polarities namely water, ethanol, ethyl acetate and hexane. ASR leaf extracts showed higher in both antioxidant components and activities than the stem extracts. Among the antioxidant components, the ethanol leaf extract showed higher phenolic (77.29 ± 1.02 mg GAE/g extract) content while the ethyl acetate leaf extract was rich in flavonoids (157.44 ± 10.19 mg RE/g extract), carotenoids (782.97 ± 10.78 mg BE/g extract) and betalains (betanin: 67.08 ± 0.49 mg/g extract; amaranthin: 93.94 ± 0.68 mg/g extract and betaxanthin: 53.92 ± 0.88 mg/g extract). Nevertheless, the ethanol leaf extract showed the highest DPPH radical scavenging activity and ABTS radical cation scavenging activity. It also exhibited highest ferric reducing activity among all the extracts. Four polyphenolic compounds from ASR leaf, namely ferulic acid, rutin, quercetin and apigenin, were identified and quantified using ultra high performance liquid chromatography. The existence of these compounds was further verified using tandem mass spectrometry. These current results indicate that ASR leaf particularly the ethanol extract has the potential to be exploited as a source of natural antioxidants
Attenuation of oxidative stress induced mitochondrial dysfunction and cytotoxicity in fibroblast cells by sulfated polysaccharide from Padina gymnospora
No full textIn this present study, isolation, characterization and protective effect of sulfated polysaccharide (SP) isolated from the brown algae Padina gymnospora was investigated. SP was isolated and characterized through FT-IR, 1H NMR, TGA, GC–MS and CHN analysis. The molecular weight of SP was found to be 16 kDa. The isolated SP contains 29.4 ± 0.35% of sulfate, 27 ± 0.11% of fucose, 0.05 ± 0.12% of protein, respectively. Furthermore, SP exhibits its excellent radical scavenging effects were evaluated by DPPH, ABTS radical scavenging and reducing power assays. Moreover, pretreatment with SP significantly mitigates H2O2 induced cytotoxicity in L-929 cells in a dose dependent manner. Furthermore, SP pretreatment ameliorates oxidative stress induced apoptosis and DNA damage, alleviates the generation of intracellular reactive oxygen species (ROS) and restores mitochondrial membrane potential (MMP) in L-929 cells through its antioxidant potential. Together, these results suggest that SP can be exploited as a natural antioxidant in the food and pharmaceutical industries
Fractional means based method for multi-oriented keyword spotting in video/scene/license plate images
No full textRetrieving desired information from databases containing video, natural scene, and license plate images through keyword spotting is a big challenge to expert systems due to different complexities that occur because of background and foreground variations of texts in real-time environments. To reduce background complexity of input images, we introduce a new model based on fractional means that considers neighboring information of pixels to widen the gap between text and background. To do so, the process obtains text candidates with the help of k-means clustering. The proposed approach explores the combination of Radon and Fourier coefficients to define context features based on regular patterns given by coefficient distributions for foreground and background of text candidates. This process eliminates non-text candidates regardless of different font types and sizes, colors, orientations and scripts, and results in representatives of texts. The proposed approach then exploits the fact that text pixels share almost the same values to restore missing text components using Canny edge image by proposing a new idea of minimum cost path based ring growing, and then outputs keywords. Furthermore, the proposed approach extracts the same above-mentioned features locally and globally for spotting words from images. Experimental results on different benchmark databases, namely, ICDAR 2013, ICDAR 2015, YVT, NUS video data, ICDAR 2013, ICDAR 2015, SVT, MSRA, UCSC, Medialab and Uninusubria license plate data show that the proposed method is effective and useful compared to the existing methods