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Epidemiology and immunodiagnostics of Strongyloides stercoralis infections among migrant workers in Malaysia
To investigate the status of Strongyloides(S.) stercoralis infections among migrant workers in Malaysia for the first time and identify risk factors. Methods: Four diagnostic methods were employed for the detection of S. stercoralis including microscopy, enzyme-linked immunosorbent assay (ELISA) using a commercial kit, ELISA using the rSs1a antigen and polymerase chain reaction (PCR). Low and semi-skilled workers from five working sectors (i.e. manufacturing, food service, agriculture and plantation, construction and domestic service) were tested on a voluntary basis. Results: The overall seroprevalence of S. stercoralis from 483 workers employing the ELISA commercial kit for IgG was 35.8% (n=173; 95% CI: 31.5%-40.1%) whereas seroprevalence using the rSs1a-ELISA was 13.0% (n=63; 95% CI: 10.0%-16.0%). Cross tabulation between the ELISA commercial kit and rSs1a-ELISA showed that only 6.4% (n=31; 95% CI: 4.2%-8.6%) of the samples were positive in both tests. Microscopic examination of all 388 fecal samples were negative; however subsequent testing by a nested PCR against DNA from the same samples successfully amplified DNA from three male subjects (0.8%; 3/388). Male workers, India and Myanmar nationality, food service occupation and those living in the hostel were statistically significant with seroprevalence (P<0.005). Conclusion: This is the first report on the epidemiology of S. stercoralis infections among the migrant workers in Malaysia. Our results highlight the importance of using appropriate diagnostic tools for detection. The presence of anti-S. stercoralis antibodies in the study population calls for improvements in personal hygiene and sanitation standards among migrant workers in Malaysia through control strategies including health education campaigns and programs aimed at increasing awareness and healthy behaviors. © 2019 Asian Pacific Journal of Tropical Medicine Produced by Wolters Kluwer-Medknow. All rights reserved
Fabrication of reduced graphene oxide/CeO2 nanocomposite for enhanced electrochemical performance
A facile hydrothermal technique was utilized for the preparation of the CeO2/rGO nanocomposite. X-ray diffraction pattern was used to identify the crystal structure and calculate the crystallite size of the prepared samples. The average crystallite sizes for CeO2 and rGO/CeO2 nanocomposites were calculated to be 14 and 12 nm, respectively. The spectral analysis confirmed the functional groups of CeO2 nanoparticles and CeO2/rGO nanocomposites. The presence of G and D band peaks as well as the CeO2 and CeO2/rGO peaks was confirmed by the FT-Raman analysis. The optical characterization of the synthesized sample was also examined with the help of UV–visible absorption and photoluminescence spectra. The surface morphology of the prepared sample was analyzed by the scanning electron microscope and transmission electron microscopy. The energy-dispersive X-ray spectroscopy analysis confirmed the existence of cerium, oxygen and carbon as the elementary components in the nanocomposite. The electrical properties such as the dielectric constant, the dielectric loss and the AC conductivity were also analyzed. The observed specific capacitances for the CeO2/rGO composite and that of pure CeO2 NPs were calculated as 89 Fg−1 and 77 Fg−1, respectively. Thus, CeO2/rGO nanocomposites can exhibit excellent capacitive performance and thereby serve as a promising anode material for supercapacitor applications. © 2019, Springer-Verlag GmbH Germany, part of Springer Nature
Objective identification of pain due to uterine contraction during the first stage of labour using continuous EEG signals and SVM
This study aimed to assess the utility of electroencephalography (EEG) as an objective marker of pain during the first stage of labour. EEG and cardiotocography (CTG) data were obtained from 10 parturient women during their first stage of labour. The study subjects reported the extent of their pain experienced due to uterine contractions, which were recorded by the CTG tracing. Simultaneous 16-channel EEG traces were obtained for spectral analysis and a subsequent machine learning classification using Support Vector Machine (SVM) aiming to predict the pain experienced in relation to uterine contractions. It was found that pain due to uterine contraction correlated positively with relative delta and beta band activities and negatively with relative theta and alpha band activities of the EEG signals. SVM using the spectral activities, statistical and non-linear features of the EEG classified the state of pain with 83% accuracy using a classification model generalizable across subjects. Furthermore, dimension reduction using Principal Component Analysis (PCA) successfully reduced the number of features used in the classification while achieving a maximum classification accuracy of 84%. Continuous EEG affords the means to assess objectively maternal pain experienced during the active contraction phase of the first stage of labour. Monitoring of the pain experience using EEG signals may complement the clinical decision-making process behind administration of epidural anaesthesia during labour. We envision future studies to investigate EEG markers of pain in other clinical states, aiming to generalize the use of EEG as an objective method of pain assessment. © 2019, Indian Academy of Sciences
Pre-enrichment step, incubation temperature and type of selective media affect the pathogenic Vibrio parahaemolyticus detection efficiency in frozen prawns
This study evaluates the performance of different detection protocols of Vibrio parahaemolyticus in frozen prawns. The effect of enrichment and incubation temperature on the selectivity of thiosulfate citrate bile sucrose (TCBS) and CHROMagar™ Vibrio (CAV) media were determined. Enumeration of V. parahaemolyticus in frozen prawns by direct-plating on CAV at 37 °C yielded the highest count compared to the other tested direct-plating protocols (p < 0.05). The enrichment step was found to increase the selectivity of TCBS for V. parahaemolyticus but did not affect the selectivity of CAV. Furthermore, trh + V. parahaemolyticus isolates were only successfully recovered from CAV, suggesting that CAV is the better media for the detection of virulent V. parahaemolyticus compared to TCBS. Repetitive Extragenic Palindromic PCR typing (REP-PCR) indicated that CAV and TCBS, as well as direct-plating or enrichment-plating are selective for different subsets of V. parahaemolyticus present in a sample. In conclusion, the current work suggests that CAV is a better selective media for detection and isolation of V. parahaemolyticus in frozen prawns. This study also suggests that direct-plating on CAV with an incubation temperature of 35–37 °C could be an alternative to Most Probable Number (MPN)-PCR for enumeration of V. parahaemolyticus in frozen prawn samples. © 2019, Bundesamt für Verbraucherschutz und Lebensmittelsicherheit (BVL)
Root and canal morphology of maxillary premolar teeth in an Egyptian subpopulation using two classification systems: a cone beam computed tomography study
Aim: To investigate the number of roots and root canal configurations using two coding systems and the root canal diverging and merging levels in extracted maxillary premolars in an Egyptian subpopulation using cone beam computed tomography (CBCT). Methodology: A total of 700 maxillary premolars were examined using CBCT in an Egyptian subpopulation. The number of roots was identified, and root canal configurations were classified according to Vertucci's classification and a new system for classifying root and canal morphology. In addition, the position where roots bifurcated and the levels where canals merged or diverged were identified. Fisher's exact test and independent t-test were used for statistical analysis, and the level of significance was set at 0.05 (P = 0.05). Results: More than half of maxillary first premolars were double-rooted, and the majority of maxillary second premolars were single-rooted (P < 0.001). Most of the double-rooted samples had bifurcations in the middle of the root. According to the Vertucci classification, canal configuration type IV was the most common in both first and second maxillary premolars. According to the new system, the code 2FP B1 P1 was the most common for maxillary first premolars, whilst 2SP B1 P1, 1SP2 and 1SP2-1 codes were the most common for maxillary second premolars. The three-canalled morphology in double- and three-rooted maxillary premolars had considerable variations. Root canal merging and diverging levels were comparable in both tooth types. Conclusion: Maxillary premolars in this Egyptian subpopulation had a wide range of root and canal anatomical variations. Clinicians should be aware of where canals merge and diverge to facilitate the treatment of all canals. The new system for classifying canal morphology describes the root and canal configurations in a more accurate and practical manner compared to the Vertucci classification. © 2018 International Endodontic Journal. Published by John Wiley & Sons Lt
Advanced Materials as Adsorbents in Microextractions for the Determination of Contaminants: A Mini Review
The widespread presence of contaminants in water demands reliable and practical analytical methods to monitor them. However, before their determination, a sample pretreatment step is necessary. This has conventionally been performed using liquid-liquid extraction (LLE) or solid-phase extraction (SPE). Advances in material sciences have since been capitalized on, with new adsorbents used in conjunction with new sample pretreatment techniques based on microextractions. In this mini-review, we showcase some of our previously reported work that demonstrates how advanced materials such as graphene, molecularly imprinted polymers (MIPs), and polymeric cyclodextrins can be used as adsorbents for the determination of contaminants such as bisphenol A, steroids, sulfonamide antibiotics, and antimicrobial agents. These adsorbents formed an important component in the micro-solid phase extraction that was used for the pretreatment of the sample. A brief introduction to the adsorbents studied and evolution of extractions is provided. The distinctive features of the analytical methods used in the real sample analysis of the stated contaminants are highlighted. © 2019 Faculty of Engineering, Universitas Indonesia
Small molecule grp94 inhibitors block dengue and Zika virus replication
Two major flaviviruses, dengue virus (DENV) and Zika virus (ZIKV), cause severe health and economic burdens worldwide. Recently, genome-wide screenings have uncovered the importance of regulators of the Hrd1 ubiquitin ligase-mediated endoplasmic reticulum (ER)-associated degradation (ERAD) pathway for flavivirus replication in host cells. Here we report the identification of the compound Bardoxolone methyl (CDDO-me) as a potent inhibitor of the Hrd1 ubiquitin ligase-mediated ERAD, which possesses a broad-spectrum activity against both DENV and ZIKV. Cellular thermal shift assay (CETSA) suggested that CDDO-me binds to grp94, a key component of the Hrd1 pathway, at a low nanomolar concentration, whereas interaction was not detected with its paralog Hsp90. CDDO-me and the grp94 inhibitor PU-WS13 substantially suppressed DENV2 replication and the cytopathic effects caused by DENV and ZIKV infection. The antiviral activities of both compounds were demonstrated for all four DENV serotypes and four ZIKV strains in multiple human cell lines. This study defines grp94 as a crucial host factor for flavivirus replication and identified CDDO-me as a potent small molecule inhibitor of flavivirus infection. Inhibition of grp94 may contribute to the antiviral activity of CDDO-me. Further investigation of grp94 inhibitors may lead to a new class of broad-spectrum anti-flaviviral medications. © 2019 Elsevier B.V
A Preliminary Study in Search of Potential Peptide Candidates for a Combinational Therapy with Cancer Chemotherapy Drug
Cancer which caused by the growth and spreading of abnormal cells in an uncontrolled manner remains a major cause of death affecting millions of people. The current cancer chemotherapy treatment modalities have several disadvantages, mostly related to their undesirable side effects. In this study, we explore the potencies of selected cell penetrating antimicrobial peptides in combination with the widely used chemotherapy drug, Doxorubicin (DOX), to increase the specificity of anticancer chemotherapy. Screening the potential peptide candidates to be developed into chemotherapy drug combination led to identification of two most potent peptides, Tachyplesin 1 (TCH) and Latarcin 1 (LTC). Cell viability of normal liver cells was reduced to 50% by 20 µM of TCH or LTC, while liver cancer cell lines lost 50% of their viability at approximately 4 µM of these peptides. The combination of DOX with TCH peptide showed the higher levels of lactate dehydrogenase (LDH) leakage from cancer cells (80%) compared to normal cells (30%). The combinational treatment DOX-peptide showed significant (P < 0.01) increase in caspase 3/7 activity compared to DOX alone. Pre-treatment of the cells with TCH peptides prior to DOX treatment considerably increased the Caspase 3/7 activities in both cell types with significant increase (P < 0.05) in cancer cells compared to normal cells. Our study demonstrate that TCH peptide is a potential anticancer peptide that could be used in combinational therapy with cancer chemotherapy drugs. © 2017, Springer Science+Business Media, LLC, part of Springer Nature
Assessment of the relationship between environmental attributes and urban quality of life in, Malaysia
Quality of life study has become an important issue among most of the researchers especially when it touches about urban living. There are many factors that significantly affect the quality of life and neighborhood satisfaction is one of the areas that concern many of the researches in the field of urbanism. Environment attributes are known as one of the factors that can affect neighborhood satisfaction. As the population is increasing rapidly in an urban area, it caused to increase in the unemployment crisis and amenities provided in urban areas. This study aims to evaluate the environmental attributes that can influence the urban resident's quality of life by adopting neighborhood satisfaction indicator as a mediator between the environmental attributes and quality of life. Primary data was collected in seven selected Klang Valley area through a survey involving 487 respondents for this study. SEM-AMOS was used for the data analysis. The findings revealed that there is partial mediation exist in the study that neighborhood satisfaction mediates the relationship between the environmental attributes and quality of life. © BEIESP
Surface roughness and the sensitivity of D-shaped optical fibre sensors
In this paper, the surface roughness characteristic of D-shaped optical fibre sensors with its effects on the sensitivity has been studied. The ULTRAPOL end and edge polishing system was used with some modifications to fabricate the D-shaped sensors with planar sensing zone from the single-mode optical fibres. The mean surface roughness of 343, 96, 25 and 9 nm was estimated at the sensing zone of the D-shaped sensors which were sequentially polished with 30, 9, 3 and 0.5 µm grit size polishing films, respectively. From the experimental results, it has been observed that surface roughness of the sensing zone does not exhibit the significant effects on the output signal strength, whereas the sensitivity of the D-shaped sensors nonlinearly related with the surface roughness of the sensing zone. The designed D-shaped optical fibre sensors have potential applications in biomedical and chemical industries. © 2019, © 2019 Informa UK Limited, trading as Taylor & Francis Group