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    High Prevalence of Toxigenic and Nontoxigenic Clostridium difficile Strains in Malaysia

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    Accumulating evidence shows a high prevalence of Clostridium difficile in Southeast Asia associated with a range of clinical presentations. However, severe infections are rarely reported. We investigated C. difficile infection (CDI) across four hospitals in Kuala Lumpur and Kota Bharu, Malaysia. Enzyme immunoassays for glutamate dehydrogenase (GDH) and toxin A or B were performed on diarrheal stool specimens collected from patients in 2015 and 2016. Specimens were also cultured and isolates of C. difficile characterized by PCR ribotyping and detection of toxin genes. In total, 437 specimens were collected and fecal toxin was detected in 3.0%. A further 16.2% of specimens were GDH positive and toxin negative. After culture, toxigenic strains were isolated from 10.3% and nontoxigenic strains from 12.4% of specimens. The most prevalent PCR ribotypes (RTs) were RT 017 (20.0%) and RT 043 (10.0%). The high prevalence of RT 017 and nontoxigenic strains in Malaysia and in neighboring Thailand and Indonesia suggests that they localize to the region of Southeast Asia, with an implication that they may mediate the burden of CDI in the region

    Interleukin-6 gene variants are associated with reduced risk of chronicity in hepatitis B virus infection in a Malaysian population

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    Interleukin-6 (IL-6) is a cytokine with a critical role in regulating the immune response to infectious disease. Studies have indicated that polymorphisms in the IL-6 gene may be linked to hepatitis B virus (HBV) infection. The purpose of the present study was to examine the association among IL-6 SNPs and haplotypes with HBV infection risk in a Malaysian population. A total of 1,246 Malaysian subjects with and without chronic hepatitis B were recruited for this study. Three IL-6 polymorphisms (rs2069837, rs1800796 and rs2066992) were genotyped using a Sequenom MassARRAY® platform. The results suggested that GC and CC genotypes of rs1800796 as well as GT and TT genotypes of rs2066992 were associated with protection against HBV infection (P<0.001). Furthermore, haplotypes GG and CT exhibited a significant association with protection against HBV (P=0.003 and =0.005, respectively); and haplotypes GG and CT exhibited a signifi­cant association with clearance of HBV infection (P=0.035 and =0.037, respectively). The present study indicates that two IL-6 SNPs (rs1800796 and rs2066992) are associated with clearance of chronic HBV or protection against HBV infection at allelic, genotypic and haplotypic levels

    Effects of a school-based substance use prevention program on students in Malaysia

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    Background: The rise in substance-use-related problems among Malaysian adolescents called for a study to assess the efficacy of an anti-drug educational program to improve the knowledge, attitude and perception (KAP) of Malaysian students regarding substance use. Methods: This study involved 573 students from four Malaysian Chinese schools in Malacca. Each student filled out a Likert-scale mandarin translated questionnaire (KAP-C) on substance use (Pre-test). Following an educational program on substance use, the KAP-C questionnaire was given again to the students, immediately following the program (PT 1), and after a month (PT 2) and two months (PT3) of the programme. Results: The students showed improvement in knowledge of the types of substance use in PT 1 (p<0.001), PT 2 (p<0.001) and PT 3 (p<0.001). The study also showed persistent changes in their attitude towards drug treatment strategies at two months following the program (p < 0.05). Changes were also noted in their attitudes towards harm reduction strategies. Perceptions towards the substance-related problems changed following the module (p=0.001), and remained even after two months (p<0.001). Conclusion: This module effectively changed the KAP of students on substance use

    Assessment of Rheological and Piezoresistive Properties of Graphene based Cement Composites

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    The concrete production processes including materials mixing, pumping, transportation, injection, pouring, moulding and compaction, are dependent on the rheological properties. Hence, in this research, the rheological properties of fresh cement paste with different content of graphene (0.03, 0.05 and 0.10% by weight of cement) were investigated. The parameters considered were test geometries (concentric cylinders and parallel plates), shear rate range (300–0.6, 200–0.6 and 100–0.6 s −1 ), resting time (0, 30 and 60 min) and superplasticizer dosage (0 and 0.1% by weight of cement). Four rheological prediction models such as Modified Bingham, Herschel–Bulkley, Bingham model and Casson model were chosen for the estimation of the yield stress, plastic viscosity and trend of the flow curves. The effectiveness of these rheological models in predicting the flow properties of cement paste was verified by considering the standard error method. Test results showed that the yield stress and the plastic viscosity increased with the increase in graphene content and resting time while the yield stress and the plastic viscosity decreased with the increase in the dosage of superplasticizer. At higher shear rate range, the yield stress increased while the plastic viscosities decreased. The Herschel–Bulkley model with the lowest average standard error and standard deviation value was found to best fit the experimental data, whereas, Casson model was found to be the most unfitted model. Graphene reduces the flow diameter and electrical resistivity up to 9.3 and 67.8% and enhances load carrying capacity and strain up to 16.7 and 70.1% of the composite specimen as compared with plain cement specimen. Moreover, it opened a new dimension for graphene-cement composite as smart sensing building construction material

    Electrochemical performance of binder-free NiO-PANI on etched carbon cloth as active electrode material for supercapacitor

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    Binder free electrode for supercapacitor application was successfully fabricated which consists of carbon cloth‑nickel oxide-polyaniline (EC-NiP). The composite electrode was prepared by growing NiO on EC via hydrothermal followed by the electrodeposition of PANI. The crystallite sizes of NiO were varied from 5.73 nm to 17.81 nm over the temperature range of 200 to 500 °C. The optimized electrode, heated at 300 °C (NIP300) showed good specific capacitance of 192.31 Fg−1 with energy density of 21.63 mWhkg−1 and 4.81 Wkg−1 of power density at 0.5 Ag−1 current density in 0.5 M H2SO4 electrolyte. The symmetrical NIP300//PVA + 0.5 M H2SO4//NIP300 cell exhibit excellent reversibility where the specific capacitance retained 72% of the initial value after 4500 cycles

    An Integrated Linearization Technique for GaAs Bipolar WCDMA Power Amplifier

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    Here we report a novel linearization and efficiency improvement technique for heterojunction bipolar transistor (HBT)-based Wireless Code Division Multiple Access (WCDMA) power amplifier. A process solution is proposed where a tantalum nitride (TaN) layer is strapped to the HBT base metal layer that resolves the current hogging issue. This is known as the strap ballasting technique. The resistance introduced by TaN improves the linear output power without trading-off its power added efficiency. At supply voltage of 4 V, the strap ballasting methodology improves the adjacent channel leakage ratio by 4.5 dB compared to the conventional base ballasting technique at output power of 28 dBm. The corresponding improvement in power added efficiency is 4%. The maximum output power delivered by power amplifier is 36 dBm. The proposed technique can be employed in the WCDMA power amplifier to minimize the fundamental trade-off issue between linear output power and efficiency

    Islamic temperature methods of soul interruption (mental health symptoms)

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    God's Word s.w.t: He (Allah) has sent to the ummi (illiterate) a messenger among them; he will recite to them his verses, he will purify them, he will teach them the Qur'an and wisdom. And verily they were before in manifest error. (Al-Jumu'ah 62: 2).The above verse contains the methods of Islamic therapy that every Muslim can use to avoid being illiterate, unable to write or read. Because they do not follow the teachings of Islam, they are so easy to be depressed and disappointed when faced with various trials in the course of travel from world life to the hereafter. They have no clue about ways to develop the personality, the way of life, the way of deeds, and the way of speaking based on Islamic teachings

    Inverse changes in plasma tetranectin and titin levels in patients with type 2 diabetes mellitus: a potential predictor of acute myocardial infarction?

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    An early intervention using biomarkers to predict acute myocardial infarction (AMI) will effectively reduce global heart attack incidence, particularly among high-risk patients with type 2 diabetes mellitus (T2DM). This study attempted to identify potential biomarkers by detecting changes in the levels of plasma proteins in T2DM patients following onset of AMI in comparison with those without AMI. Volunteer T2DM patients without AMI (control; n=10) and T2DM patients with AMI (n=10) were recruited. Plasma samples from these patients were evaluated via two-dimensional gel electrophoresis (2DE) to screen for proteins with level changes between the two groups. The abundance of spots on gel images was analyzed using Progenesis SameSpots and subjected to false discovery rate (FDR) analysis. Protein spots with statistically significant changes of at least 1.5 fold were selected for mass spectrometry (MS) analysis. Due to strong cardiac connections, tetranectin and titin were evaluated by enzymelinked immunosorbent assay (ELISA). The adjusted P-values and fold changes between the two groups resulted in identification of 34 protein spots with significantly altered abundance. Upon MS analysis, 17 plasma proteins were identified: tetranectin, titin, clusterin, haptoglobin, myosin-13, zinc fnger protein 445, DNA repair protein RAD50, serum albumin, apolipoprotein A-IV, caspase-6, aminoacyl tRNA synthase complex-interacting multifunctional protein 1, serotransferrin, retinol-binding protein 4, transthyretin, alpha-1-antitrypsin, apolipoprotein A-I and serum amyloid A. Comparable patterns of changes in tetranectin and titin between the control and AMI groups were confirmed using ELISA. In summary, tetranectin and titin in plasma appeared to be closely associated with the onset of AMI among T2DM patients and can be used as potential biomarkers for prediction of a cardiac event, though this requires validation in a prospective cohort study

    Epithelial-to-mesenchymal transition (EMT) causing acquired resistance to afatinib in a patient with epidermal growth factor receptor (EGFR)-mutant lung adenocarcinoma

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    We report the first case of epithelial-to-mesenchymal transition (EMT) as the cause of acquired resistance to the second-generation EGFR-tyrosine kinase inhibitor (TKI), afatinib in a patient with advanced non-small cell lung cancer (NSCLC) harboring a sensitizing EGFR mutation. Patients with EGFRmutant NSCLC inevitably develop acquired resistance while on EGFR-TKI treatment. EMT which renders cancer cells more invasive and migratory is one of the mechanisms of acquired resistance to EGFR-TKIs and correlates with a poor prognosis. Possible therapeutic strategies in patients with EMT include blocking M2 muscarinic receptor signalling, targeting EMT with histone deacetylase inhibitors such as entinostat and MEK-inhibitors such as selumetinib, inhibition of microRNAs, immunotherapy and inhibiting fibroblast growth factor receptor-1

    Guerbet glycolipids from mannose: liquid crystals properties

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    Using mannose as the sugar head, five Guerbet glycolipids with chain ranges from C 8 to C 24 were synthesised and studied for their liquid crystal behaviour. Differential scanning calorimetry, optical polarising microscopy and small-angle X-ray scattering were employed to determine the thermal, phase and structure properties. Unlike monoalkylated glycolipids, these Guerbet mannosides showed a glass transition below 0°C, except for α-Man-OC 14 C 10 . In the dry state, lamellar was observed for α-Man-OC 6 C 2 and α-Man-OC 8 C 4 , while α-Man-OC 12 C 8 and α-Man-OC 14 C 10 formed non-lamellar phases, including inverse bicontinuous cubic phase of space group Ia3d and inverse hexagonal phase, respectively. The phase for middle-chain mannoside (α-Man-OC 10 C 6 ) could not be assigned conclusively at room temperature, but this metastable phase forms lamellar above 37°C. The partial binary phase diagrams in water were also determined. Under excess water conditions at room and physiological temperatures, these materials form normal micellar solution, lamellar, inverse bicontinuous cubic of space group Pn3m and inverse hexagonal phases. The results were compared with those from other monosaccharide glycolipids from the same sugar Guerbet family. Although these compounds are obvious candidate material for lyotropic applications such as drug carrier and protein crystallisation medium, possible thermotropic application is now being explored

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