Browse publications by year: 2017

  1. Abbas Ali M, Anowarul Islam M, Othman NH, Noor AM
    J Food Sci Technol, 2017 Dec;54(13):4335-4343.
    PMID: 29184239 DOI: 10.1007/s13197-017-2904-1
    The oxidative stability and fatty acid composition of groundnut seed oil (GSO) exposed to microwaves were evaluated during heating at 170 °C. During heating, the oxidative indices such as free fatty acid, peroxide value, p-anisidine value, TOTOX, thiobarbituric acid value, specific extinctions, and color value were increased. The increments were found to be higher in unroasted seed oils compared to roasted ones indicating lower release of lipid oxidation products in roasted GSO. After 9 h heating, the relative content of polyunsaturated fatty acid (PUFA) decreased to 89.53% and that of saturated fatty acid (SFA) increased to 117.46% in unroasted sample. The relative content of PUFA decreased to 92.05% and that of SFA increased to 105.76% in 7.5 min roasted sample after 9 h of heating. However, the roasting process slowed down the oxidative deterioration of PUFA. With increased heating times, an appreciable loss was more apparent in the triacylglycerol species OLL and OOL in unroasted samples compared to roasted ones. In FTIR, the peak intensities in unroasted samples were markedly changed in comparison with roasted samples during heating. The roasting of groundnut seed prior to the oil extraction reduced the oxidative degradation of oil samples; thereby increasing heat stability.
    MeSH terms: Aniline Compounds; Fatty Acids; Fatty Acids, Unsaturated; Hot Temperature; Heating; Microwaves; Oils; Peroxides; Seeds; Thiobarbiturates; Triglycerides; Spectroscopy, Fourier Transform Infrared
  2. Gopalsamy B, Farouk AAO, Tengku Mohamad TAS, Sulaiman MR, Perimal EK
    J Pain Res, 2017;10:2605-2619.
    PMID: 29184437 DOI: 10.2147/JPR.S143024
    Background: Neuropathic pain is a debilitating condition that severely affects the quality of life for those with this pain condition, and treatment for pain relief is greatly sought-after. Zerumbone (Zer), a sesquiterpene compound isolated from the rhizomes of a Southeast Asian ginger plant, Zingiber zerumbet (L.) Roscoe ex Smith. (Zingiberaceae), showed antinociceptive and antiinflammatory properties when previously tested on models of nociception and inflammation.

    Objective: This study investigated the effects of prophylactic administration of zerumbone on allodynia and hyperalgesia in a mouse model of chronic constriction injury (CCI)-induced neuropathic pain.

    Methods: Intraperitoneal administration of Zer (5-50 mg/kg) from day 1 post-surgery was carried out to identify the onset and progression of the pain condition. Responses toward mechanical and cold allodynia, and mechanical and thermal hyperalgesia were assessed on days 3, 5, 7, 9, 11, and 14 post-surgery. Blood plasma and spinal cord levels of interleukin (IL)-1β, IL-6, tumor necrosis factor-α, and IL-10 were screened using enzyme-linked immunosorbent assay on day 15.

    Results: Zer (10 and 50 mg/kg) attenuated pain symptoms on all days of behavioral testing without any signs of sedation in the rotarod test. ED50 values for mechanical allodynia, cold allodynia, thermal hyperalgesia, and mechanical hyperalgesia were 9.25, 9.507, 8.289, and 9.801 mg/kg, respectively. Blood plasma and spinal levels of IL-1β, IL-6, and tumor necrosis factor-α but not IL-10 were significantly (p<0.05) suppressed by zer treatment.

    Discussion and conclusion: Zer exhibits its antiallodynic and antihyperalgesic properties via reduced sensitization at nociceptor neurons possibly through the suppression of inflammatory mediators. Zer may prove to be a novel and beneficial alternative for the management of neuropathic pain.

  3. Sinniah A, Yazid S, Flower RJ
    Front Pharmacol, 2017;8:827.
    PMID: 29184504 DOI: 10.3389/fphar.2017.00827
    The anti-allergic cromones were originally synthesized in the 1960s by Fisons Plc, and the first drug to emerge from this program, disodium cromoglycate was subsequently marketed for the treatment of asthma and other allergic conditions. Whilst early studies demonstrated that the ability of the cromones to prevent allergic reactions was due to their 'mast cell stabilizing' properties, the exact pharmacological mechanism by which this occurred, remained a mystery. Here, we briefly review the history of these drugs, recount some aspects of their pharmacology, and discuss two new explanations for their unique actions. We further suggest how these findings could be used to predict further uses for the cromones.
    MeSH terms: Asthma; Cromolyn Sodium; Hypersensitivity; Mast Cells; Anti-Allergic Agents; Anti-Asthmatic Agents
  4. Parasuraman S, Sam AT, Yee SWK, Chuon BLC, Ren LY
    Int J Pharm Investig, 2017 Jul-Sep;7(3):125-131.
    PMID: 29184824 DOI: 10.4103/jphi.JPHI_56_17
    Objective: This study aimed to study the mobile phone addiction behavior and awareness on electromagnetic radiation (EMR) among a sample of Malaysian population.

    Methods: This online study was conducted between December 2015 and 2016. The study instrument comprised eight segments, namely, informed consent form, demographic details, habituation, mobile phone fact and EMR details, mobile phone awareness education, psychomotor (anxious behavior) analysis, and health issues. Frequency of the data was calculated and summarized in the results.

    Results: Totally, 409 respondents participated in the study. The mean age of the study participants was 22.88 (standard error = 0.24) years. Most of the study participants developed dependency with smartphone usage and had awareness (level 6) on EMR. No significant changes were found on mobile phone addiction behavior between the participants having accommodation on home and hostel.

    Conclusion: The study participants were aware about mobile phone/radiation hazards and many of them were extremely dependent on smartphones. One-fourth of the study population were found having feeling of wrist and hand pain because of smartphone use which may lead to further physiological and physiological complication.
    MeSH terms: Smartphone; Demography; Emotions; Pain; Surveys and Questionnaires; Wrist; Wrist Joint; Consent Forms; Electromagnetic Radiation
  5. Alagdar GSA, Oo MK, Sengupta P, Mandal UK, Jaffri JM, Chatterjee B
    Int J Pharm Investig, 2017 12 1;7(3):142-148.
    PMID: 29184827 DOI: 10.4103/jphi.JPHI_54_17
    Background and Objective: One of the established strategies to improve solubility and dissolution rate of poorly water-soluble drugs is solid dispersion (SD). Polyethylene glycol (PEG) is used as common carrier despite its stability problem which may be overcome by the addition of hydrophobic polymer. The present research aimed to develop an SD formulation with ibuprofen, a poor water-soluble BCS Class II drug as active pharmaceutical ingredient (API) and PEG 4000-ethyl cellulose (EC) as binary carrier.

    Methods: Melt mixing SD method was employed using a ratio of API: binary carrier (1:3.5 w/w) (SDPE). Another SD was prepared using only PEG (SDP) as a carrier for comparative study. The developed formulation was evaluated using optical microscopy, scanning electron microscopy (SEM), determination of moisture content, differential scanning calorimetry (DSC), in vitro dissolution test, attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR) and flow properties.

    Results: SEM and DSC indicated the conversion of crystalline ibuprofen to fine partly amorphous solid dispersion, which was responsible for the increase in dissolution rate of SD than a physical mixture. The release characteristics within 1 h from the higher to the lower value were the SDPE> SDP> physical mixture. Flow property evaluation using the angle of repose showed no difference between SD and PM. However, by Carr index and Hausner ratio, the flow properties of SDPE was excellent.

    Conclusion: The SD formulation with the PEG 4000-EC carrier can be effective to enhance in vitro dissolution of ibuprofen immediate release dosage form.

  6. Loh BCS, Then PHH
    Mhealth, 2017;3:45.
    PMID: 29184897 DOI: 10.21037/mhealth.2017.09.01
    Cardiovascular diseases are one of the top causes of deaths worldwide. In developing nations and rural areas, difficulties with diagnosis and treatment are made worse due to the deficiency of healthcare facilities. A viable solution to this issue is telemedicine, which involves delivering health care and sharing medical knowledge at a distance. Additionally, mHealth, the utilization of mobile devices for medical care, has also proven to be a feasible choice. The integration of telemedicine, mHealth and computer-aided diagnosis systems with the fields of machine and deep learning has enabled the creation of effective services that are adaptable to a multitude of scenarios. The objective of this review is to provide an overview of heart disease diagnosis and management, especially within the context of rural healthcare, as well as discuss the benefits, issues and solutions of implementing deep learning algorithms to improve the efficacy of relevant medical applications.
    MeSH terms: Machine Learning; Algorithms; Cardiovascular Diseases; Cause of Death; Delivery of Health Care; Developing Countries; Diagnosis, Computer-Assisted; Health Facilities; Heart Diseases; Telemedicine
  7. Keong KM, Aziz I, Yin Wei CC
    J Orthop Surg (Hong Kong), 2017 01 01;25(1):2309499016684431.
    PMID: 29185383 DOI: 10.1177/2309499016684431
    PURPOSE: This study aims to derive a formula to predict post-operative height increment in Lenke 1 and Lenke 2 adolescent idiopathic scoliosis (AIS) patients using preoperative radiological parameters.

    METHODS: This study involved 70 consecutive Lenke 1 and 2 AIS patients who underwent scoliosis correction with alternate-level pedicle screw instrumentation. Preoperative parameters that were measured included main thoracic (MT) Cobb angle, proximal thoracic (PT) Cobb angle, lumbar Cobb angle as well as thoracic kyphosis. Side-bending flexibility (SBF) and fulcrum-bending flexibility (FBF) were derived from the measurements. Preoperative height and post-operative height increment was measured by an independent observer using a standardized method.

    RESULTS: MT Cobb angle and FB Cobb angle were significant predictors ( p < 0.001) of height increment from multiple linear regression analysis ( R = 0.784, R2 = 0.615). PT Cobb angle, lumbar, SB Cobb angle, preoperative height and number of fused segment were not significant predictors for the height increment based on the multivariable analysis. Increase in post-operative height could be calculated by the formula: Increase in height (cm) = (0.09 × preoperative MT Cobb angle) - (0.04 x FB Cobb angle) - 0.5.

    CONCLUSION: The proposed formula of increase in height (cm) = (0.09 × preoperative MT Cobb angle) - (0.04 × FB Cobb angle) - 0.5 could predict post-operative height gain to within 5 mm accuracy in 51% of patients, within 10 mm in 70% and within 15 mm in 86% of patients.

    MeSH terms: Adolescent; Algorithms; Body Height*; Child; Female; Humans; Male; Predictive Value of Tests; Radiography; Scoliosis/surgery*; Spinal Fusion*; Thoracic Vertebrae/surgery*; Linear Models; Treatment Outcome; Young Adult; Pedicle Screws*
  8. Lim EL, Ngeow WC, Lim D
    Braz Oral Res, 2017 Nov 27;31:e97.
    PMID: 29185606 DOI: 10.1590/1807-3107bor-2017.vol31.0097
    The objective of this study was to measure the topographic thickness of the lateral wall of the maxillary sinus in selected Asian populations. Measurements were made on the lateral walls of maxillary sinuses recorded using CBCT in a convenient sample of patients attending an Asian teaching hospital. The points of measurement were the intersections between the axes along the apices of the canine, first premolar, and second premolar and along the mesiobuccal and distobuccal apices of the first and second molars and horizontal planes 10 mm, 20 mm, 30 mm and 40 mm beneath the orbital floor. The CBCT images of 109 patients were reviewed. The mean age of the patients was 33.0 (SD 14.8) years. Almost three quarters (71.8%) of the patients were male. The mean bone thickness decreased beginning at the 10-mm level and continuing to 40 mm below the orbital floor. Few canine regions showed encroachment of the maxillary sinus. The thickness of the buccal wall gradually increased from the canine region (where sinus encroachment of the canine region was present) to the first molar region, after which it decreased to the thickness observed at the canine region. The buccal wall of the maxillary sinus became thicker anteroposteriorly, except in the region of the second molar, and thinner superoinferiorly. These changes will affect the approach used to osteotomize the lateral sinus wall for oral surgery and for the sinus lift procedure.
    MeSH terms: Adolescent; Adult; Age Factors; Analysis of Variance; Child; Child, Preschool; Cross-Sectional Studies; Female; Humans; Infant; Male; Maxillary Sinus/anatomy & histology*; Maxillary Sinus/surgery; Middle Aged; Mouth/anatomy & histology*; Mouth/surgery; Reference Values; Sex Factors; Tooth/anatomy & histology; European Continental Ancestry Group; Asian Continental Ancestry Group; Cone-Beam Computed Tomography/methods; Young Adult
  9. Takeuchi Y, Soda R, Diway B, Kuda TA, Nakagawa M, Nagamasu H, et al.
    PLoS One, 2017;12(11):e0187273.
    PMID: 29186138 DOI: 10.1371/journal.pone.0187273
    This study explored the conservation values of communally reserved forests (CRFs), which local indigenous communities deliberately preserve within their area of shifting cultivation. In the current landscape of rural Borneo, CRFs are the only option for conservation because other forested areas have already been logged or transformed into plantations. By analyzing their alpha and beta diversity, we investigated how these forests can contribute to restore regional biodiversity. Although CRFs were fragmented and some had been disturbed in the past, their tree species diversity was high and equivalent to that of primary forests. The species composition of intact forests and forests disturbed in the past did not differ clearly, which indicates that past logging was not intensive. All CRFs contained unique and endangered species, which are on the IUCN Red List, Sarawak protected plants, or both. On the other hand, the forest size structure differed between disturbed and intact CRFs, with the disturbed CRFs consisting of relatively smaller trees. Although the beta diversity among CRFs was also high, we found a high contribution of species replacement (turnover), but not of richness difference, in the total beta diversity. This suggests that all CRFs have a conservation value for restoring the overall regional biodiversity. Therefore, for maintaining the regional species diversity and endangered species, it would be suitable to design a conservation target into all CRFs.
    MeSH terms: Animals; Borneo; Conservation of Natural Resources*; Humans; Biodiversity*; Endangered Species; Forests*
  10. Veera Singham G, Othman AS, Lee CY
    PLoS One, 2017;12(11):e0186690.
    PMID: 29186140 DOI: 10.1371/journal.pone.0186690
    Dispersal of soil-dwelling organisms via the repeatedly exposed Sunda shelf through much of the Pleistocene in Southeast Asia has not been studied extensively, especially for invertebrates. Here we investigated the phylogeography of an endemic termite species, Macrotermes gilvus (Hagen), to elucidate the spatiotemporal dynamics of dispersal routes of terrestrial fauna in Pleistocene Southeast Asia. We sampled 213 termite colonies from 66 localities throughout the region. Independently inherited microsatellites and mtDNA markers were used to infer the phylogeographic framework of M. gilvus. Discrete phylogeographic analysis and molecular dating based on fossil calibration were used to infer the dynamics of M. gilvus dispersal in time and space across Southeast Asia. We found that the termite dispersal events were consistently dated within the Pleistocene time frame. The dispersal pattern was multidirectional, radiating eastwards and southwards out of Indochina, which was identified as the origin for dispersal events. We found no direct dispersal events between Sumatra and Borneo despite the presence of a terrestrial connection between them during the Pleistocene. Instead, central Java served as an important link allowing termite colonies to be established in Borneo and Sumatra. Our findings support the hypothesis of a north-south dispersal corridor in Southeast Asia and suggest the presence of alternative dispersal routes across Sundaland during the Pleistocene. For the first time, we also propose that a west-east dispersal through over-water rafting likely occurred across the Pleistocene South China Sea. We found at least two independent entry routes for terrestrial species to infiltrate Sumatra and Borneo at different times.
    MeSH terms: Animals; Asia, Southeastern; DNA, Mitochondrial/genetics; Female; Fossils*; Genetic Variation; Microsatellite Repeats/genetics; Isoptera/classification*; Isoptera/genetics; Phylogeography*
  11. Chew KS, van Merrienboer JJG, Durning SJ
    BMC Med Educ, 2017 Nov 29;17(1):234.
    PMID: 29187172 DOI: 10.1186/s12909-017-1078-x
    BACKGROUND: A key challenge clinicians face when considering differential diagnoses is whether the patient data have been adequately collected. Insufficient data may inadvertently lead to premature closure of the diagnostic process. This study aimed to test the hypothesis that the application of a mnemonic checklist helps to stimulate more patient data collection, thus leading to better diagnostic consideration.

    METHODS: A total of 88 final year medical students were assigned to either an educational intervention group or a control group in a non-equivalent group post-test only design. Participants in the intervention group received a tutorial on the use of a mnemonic checklist aimed to minimize cognitive errors in clinical decision-making. Two weeks later, the participants in both groups were given a script concordance test consisting of 10 cases, with 3 items per case, to assess their clinical decisions when additional data are given in the case scenarios.

    RESULTS: The Mann-Whitney U-test performed on the total scores from both groups showed no statistical significance (U = 792, z = -1.408, p = 0.159). When comparisons were made for the first half and the second half of the SCT, it was found that participants in the intervention group performed significantly better than participants in the control group in the first half of the test, with median scores of 9.15 (IQR 8.00-10.28) vs. 8.18 (IQR 7.16-9.24) respectively, U = 642.5, z = -2.661, p = 0.008. No significant difference was found in the second half of the test, with the median score of 9.58 (IQR 8.90-10.56) vs. 9.81 (IQR 8.83-11.12) for the intervention group and control group respectively (U = 897.5, z = -0.524, p = 0.60).

    CONCLUSION: Checklist use in differential diagnoses consideration did show some benefit. However, this benefit seems to have been traded off by the time and effort in using it. More research is needed to determine whether this benefit could be translated into clinical practice after repetitive use.

    MeSH terms: Clinical Decision-Making/methods*; Diagnosis, Differential; Diagnostic Errors/prevention & control*; Education, Medical, Undergraduate*; Female; Humans; Learning; Malaysia; Male; Practice Guidelines as Topic; Problem-Based Learning; Young Adult; Checklist*
  12. Neagu D, Papaioannou EI, Ramli WKW, Miller DN, Murdoch BJ, Ménard H, et al.
    Nat Commun, 2017 11 30;8(1):1855.
    PMID: 29187751 DOI: 10.1038/s41467-017-01880-y
    Metal nanoparticles prepared by exsolution at the surface of perovskite oxides have been recently shown to enable new dimensions in catalysis and energy conversion and storage technologies owing to their socketed, well-anchored structure. Here we show that contrary to general belief, exsolved particles do not necessarily re-dissolve back into the underlying perovskite upon oxidation. Instead, they may remain pinned to their initial locations, allowing one to subject them to further chemical transformations to alter their composition, structure and functionality dramatically, while preserving their initial spatial arrangement. We refer to this concept as chemistry at a point and illustrate it by tracking individual nanoparticles throughout various chemical transformations. We demonstrate its remarkable practical utility by preparing a nanostructured earth abundant metal catalyst which rivals platinum on a weight basis over hundreds of hours of operation. Our concept enables the design of compositionally diverse confined oxide particles with superior stability and catalytic reactivity.
    MeSH terms: Catalysis; Oxides; Platinum; Titanium; Calcium Compounds; Metal Nanoparticles
  13. Ikram NKBK, Simonsen HT
    Front Plant Sci, 2017;8:1966.
    PMID: 29187859 DOI: 10.3389/fpls.2017.01966
    Malaria is still an eminent threat to major parts of the world population mainly in sub-Saharan Africa. Researchers around the world continuously seek novel solutions to either eliminate or treat the disease. Artemisinin, isolated from the Chinese medicinal herb Artemisia annua, is the active ingredient in artemisinin-based combination therapies used to treat the disease. However, naturally artemisinin is produced in small quantities, which leads to a shortage of global supply. Due to its complex structure, it is difficult chemically synthesize. Thus to date, A. annua remains as the main commercial source of artemisinin. Current advances in genetic and metabolic engineering drives to more diverse approaches and developments on improving in planta production of artemisinin, both in A. annua and in other plants. In this review, we describe efforts in bioengineering to obtain a higher production of artemisinin in A. annua and stable heterologous in planta systems. The current progress and advancements provides hope for significantly improved production in plants.
  14. Both S, Elias DMO, Kritzler UH, Ostle NJ, Johnson D
    Ecol Evol, 2017 Nov;7(22):9307-9318.
    PMID: 29187970 DOI: 10.1002/ece3.3460
    In hyperdiverse tropical forests, the key drivers of litter decomposition are poorly understood despite its crucial role in facilitating nutrient availability for plants and microbes. Selective logging is a pressing land use with potential for considerable impacts on plant-soil interactions, litter decomposition, and nutrient cycling. Here, in Borneo's tropical rainforests, we test the hypothesis that decomposition is driven by litter quality and that there is a significant "home-field advantage," that is positive interaction between local litter quality and land use. We determined mass loss of leaf litter, collected from selectively logged and old-growth forest, in a fully factorial experimental design, using meshes that either allowed or precluded access by mesofauna. We measured leaf litter chemical composition before and after the experiment. Key soil chemical and biological properties and microclimatic conditions were measured as land-use descriptors. We found that despite substantial differences in litter quality, the main driver of decomposition was land-use type. Whilst inclusion of mesofauna accelerated decomposition, their effect was independent of land use and litter quality. Decomposition of all litters was slower in selectively logged forest than in old-growth forest. However, there was significantly greater loss of nutrients from litter, especially phosphorus, in selectively logged forest. The analyses of several covariates detected minor microclimatic differences between land-use types but no alterations in soil chemical properties or free-living microbial composition. These results demonstrate that selective logging can significantly reduce litter decomposition in tropical rainforest with no evidence of a home-field advantage. We show that loss of key limiting nutrients from litter (P & N) is greater in selectively logged forest. Overall, the findings hint at subtle differences in microclimate overriding litter quality that result in reduced decomposition rates in selectively logged forests and potentially affect biogeochemical nutrient cycling in the long term.
  15. Hassan MA, Malik AS, Fofi D, Saad N, Meriaudeau F
    Biomed Opt Express, 2017 Nov 01;8(11):4838-4854.
    PMID: 29188085 DOI: 10.1364/BOE.8.004838
    In this paper we present a novel health monitoring method by estimating the heart rate and respiratory rate using an RGB camera. The heart rate and the respiratory rate are estimated from the photoplethysmography (PPG) and the respiratory motion. The method mainly operates by using the green spectrum of the RGB camera to generate a multivariate PPG signal to perform multivariate de-noising on the video signal to extract the resultant PPG signal. A periodicity based voting scheme (PVS) was used to measure the heart rate and respiratory rate from the estimated PPG signal. We evaluated our proposed method with a state of the art heart rate measuring method for two scenarios using the MAHNOB-HCI database and a self collected naturalistic environment database. The methods were furthermore evaluated for various scenarios at naturalistic environments such as a motion variance session and a skin tone variance session. Our proposed method operated robustly during the experiments and outperformed the state of the art heart rate measuring methods by compensating the effects of the naturalistic environment.
  16. Hussein AF, Hashim SJ, Aziz AFA, Rokhani FZ, Adnan WAW
    J Med Syst, 2017 Nov 29;42(1):15.
    PMID: 29188389 DOI: 10.1007/s10916-017-0871-8
    The non-stationary and multi-frequency nature of biomedical signal activities makes the use of time-frequency distributions (TFDs) for analysis inevitable. Time-frequency analysis provides simultaneous interpretations in both time and frequency domain enabling comprehensive explanation, presentation and interpretation of electrocardiogram (ECG) signals. The diversity of TFDs and specific properties for each type show the need to determine the best TFD for ECG analysis. In this study, a performance evaluation of five TFDs in term of ECG abnormality detection is presented. The detection criteria based on extracted features from most important ECG signal components (QRS) to detect normal and abnormal cases. This is achieved by estimating its energy concentration magnitude using the TFDs. The TFDs analyse ECG signals in one-minute interval instead of conventional time domain approach that analyses based on beat or frame containing several beats. The MIT-BIH normal sinus rhythm ECG database total records of 18 long-term ECG sampled at 128 Hz have been analysed. The tested TFDs include Dual-Tree Wavelet Transform, Spectrogram, Pseudo Wigner-Ville, Choi-Williams, and Born-Jordan. Each record is divided into one-minute slots, which is not considered previously, and analysed. The sample periods (slots) are randomly selected ten minutes interval for each record. This result with 99.44% detection accuracy for 15,735 ECG beats shows that Choi-Williams distribution is most reliable to be used for heart problem detection especially in automated systems that provide continuous monitoring for long time duration.
    MeSH terms: Algorithms; Arrhythmias, Cardiac/diagnosis*; Arrhythmias, Cardiac/physiopathology; Electrocardiography/methods*; Humans; Sensitivity and Specificity; Signal Processing, Computer-Assisted*; Time Factors; Wavelet Analysis
  17. Azri FA, Selamat J, Sukor R
    Sensors (Basel), 2017 Nov 30;17(12).
    PMID: 29189760 DOI: 10.3390/s17122776
    Palm kernel cake (PKC) is the solid residue following oil extraction of palm kernels and useful to fatten animals either as a single feed with only minerals and vitamins supplementation, or mixed with other feedstuffs such as corn kernels or soy beans. The occurrence of mycotoxins (aflatoxins, ochratoxins, zearalenone, and fumonisins) in feed samples affects the animal's health and also serves as a secondary contamination to humans via consumption of eggs, milk and meats. Of these, aflatoxin B₁ (AFB₁) is the most toxically potent and a confirmed carcinogen to both humans and animals. Methods such as High Performance Liquid Chromatography (HPLC) and Liquid Chromatography-Mass Spectrometry (LC-MS/MS) are common in the determination of mycotoxins. However, these methods usually require sample pre-treatment, extensive cleanup and skilled operator. Therefore, in the present work, a rapid method of electrochemical immunosensor for the detection of AFB₁ was developed based on an indirect competitive enzyme-linked immunosorbent assay (ELISA). Multi-walled carbon nanotubes (MWCNT) and chitosan (CS) were used as the electrode modifier for signal enhancement.N-ethyl-N'-(3-dimethylaminopropyl)-carbodiimide (EDC) andN-hydroxysuccinimide (NHS) activated the carboxyl groups at the surface of nanocomposite for the attachment of AFB₁-BSA antigen by covalent bonding. An indirect competitive reaction occurred between AFB₁-BSA and free AFB₁ for the binding site of a fixed amount of anti-AFB₁ antibody. A catalytic signal based on horseradish peroxidase (HRP) in the presence of hydrogen peroxide (H₂O₂) and 3,3',5,5'-tetramethylbenzidine (TMB) mediator was observed as a result of attachment of the secondary antibody to the immunoassay system. As a result, the reduction peak of TMB(Ox)was measured by using differential pulse voltammetry (DPV) analysis. Based on the results, the electrochemical surface area was increased from 0.396 cm² to 1.298 cm² due to the electrode modification with MWCNT/CS. At the optimal conditions, the working range of the electrochemical immunosensor was from 0.0001 to 10 ng/mL with limit of detection of 0.1 pg/mL. Good recoveries were obtained for the detection of spiked feed samples (PKC, corn kernels, soy beans). The developed method could be used for the screening of AFB₁ in real samples.
    MeSH terms: Aflatoxins; Animals; Chromatography, High Pressure Liquid; Zea mays; Horseradish Peroxidase; Humans; Hydrogen Peroxide; Mycotoxins; Ochratoxins; Soybeans; Zearalenone; Aflatoxin B1; Fumonisins; Nanotubes, Carbon; Chitosan
  18. Muslim MT, Selamat H, Alimin AJ, Haniff MF
    PLoS One, 2017;12(11):e0188553.
    PMID: 29190779 DOI: 10.1371/journal.pone.0188553
    In a modern small gasoline engine fuel injection system, the load of the engine is estimated based on the measurement of the manifold absolute pressure (MAP) sensor, which took place in the intake manifold. This paper present a more economical approach on estimating the MAP by using only the measurements of the throttle position and engine speed, resulting in lower implementation cost. The estimation was done via two-stage multilayer feed-forward neural network by combining Levenberg-Marquardt (LM) algorithm, Bayesian Regularization (BR) algorithm and Particle Swarm Optimization (PSO) algorithm. Based on the results found in 20 runs, the second variant of the hybrid algorithm yields a better network performance than the first variant of hybrid algorithm, LM, LM with BR and PSO by estimating the MAP closely to the simulated MAP values. By using a valid experimental training data, the estimator network that trained with the second variant of the hybrid algorithm showed the best performance among other algorithms when used in an actual retrofit fuel injection system (RFIS). The performance of the estimator was also validated in steady-state and transient condition by showing a closer MAP estimation to the actual value.
    MeSH terms: Algorithms*; Pressure*; Mechanical Phenomena
  19. Ghanghoria R, Kesharwani P, Jain NK
    Mini Rev Med Chem, 2017;17(18):1713-1724.
    PMID: 26891934 DOI: 10.2174/1389557516666160219122002
    The experimental models are of vital significance to provide information regarding biological as well as genetic factors that control the phenotypic characteristics of the disease and serve as the foundation for the development of rational intervention stratagem. This review highlights the importance of experimental models in the field of cancer management. The process of pathogenesis in cancer progression, invasion and metastasis can be successfully explained by employing clinically relevant laboratory models of the disease. Cancer cell lines have been used extensively to monitor the process of cancer pathogenesis process by controlling growth regulation and chemo-sensitivity for the evaluation of novel therapeutics in both in vitro and xenograft models. The experimental models have been used for the elaboration of diagnostic or therapeutic protocols, and thus employed in preclinical studies of bioactive agents relevant for cancer prevention. The outcome of this review should provide useful information in understanding and selection of various models in accordance with the stage of cancer.
    MeSH terms: Animals; Antineoplastic Agents/therapeutic use; Cell Survival/drug effects; Disease Models, Animal*; Humans; Neoplasms/diagnosis*; Neoplasms/drug therapy; Neoplasms/genetics; Apoptosis/drug effects; Cell Proliferation/drug effects
  20. Wu Y, Yang Z, Law JB, He AY, Abbas AA, Denslin V, et al.
    Tissue Eng Part A, 2017 01;23(1-2):43-54.
    PMID: 27824280 DOI: 10.1089/ten.TEA.2016.0123
    Stem cell differentiation is guided by contact with the physical microenvironment, influence by both topography and mechanical properties of the matrix. In this study, the combined effect of substratum nano-topography and mechanical stiffness in directing mesenchymal stem cell (MSC) chondrogenesis was investigated. Three polyesters of varying stiffness were thermally imprinted to create nano-grating or pillar patterns of the same dimension. The surface of the nano-patterned substrate was coated with chondroitin sulfate (CS) to provide an even surface chemistry, with cell-adhesive and chondro-inductive properties, across all polymeric substrates. The surface characteristic, mechanical modulus, and degradation of the CS-coated patterned polymeric substrates were analyzed. The cell morphology adopted on the nano-topographic surfaces were accounted by F-actin distribution, and correlated to the cell proliferation and chondrogenic differentiation outcomes. Results show that substratum stiffness and topographical cues affected MSC morphology and aggregation, and influenced the phenotypic development at the earlier stage of chondrogenic differentiation. Hyaline-like cartilage with middle/deep zone cartilage characteristics was generated on softer pillar surface, while on stiffer nano-pillar material MSCs showed potential to generate constituents of hyaline/fibro/hypertrophic cartilage. Fibro/superficial zone-like cartilage could be derived from nano-grating of softer stiffness, while stiffer nano-grating resulted in insignificant chondrogenesis. This study demonstrates the possibility of refining the phenotype of cartilage generated from MSCs by manipulating surface topography and material stiffness.
    MeSH terms: Cartilage/cytology; Cartilage/metabolism; Chondroitin Sulfates/chemistry*; Humans; Surface Properties; Compressive Strength*; Coated Materials, Biocompatible/chemistry*; Chondrogenesis*; Mesenchymal Stromal Cells/cytology; Mesenchymal Stromal Cells/metabolism*
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