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  1. Comparison of protein-free defined media, and effect of L-cysteine and ascorbic acid supplementation on viability of axenic Entamoeba histolytica
    Wong WK, Tan ZN, Lim BH, Mohamed Z, Olivos-Garcia A, Noordin R
    Parasitol Res, 2011 Feb;108(2):425-30.
    PMID: 20922423 DOI: 10.1007/s00436-010-2083-8
    Entamoeba histolytica is the etiologic agent for amoebiasis. The excretory-secretory (ES) products of the trophozoites contain virulence factors and antigens useful for diagnostic applications. Contaminants from serum supplements and dead trophozoites impede analysis of ES. Therefore, a protein-free medium that can sustain maximum viability of E. histolytica trophozoites for the longest time duration will enable collection of contaminant-free and higher yield of ES products. In the present study, we compared the efficacy of four types of media in maintaining ≥ 95% trophozoite viability namely Roswell Memorial Park Institute (RPMI-1640), Dulbecco's Modified Eagle Medium (DMEM), phosphate-buffered saline for amoeba (PBS-A), and Hank's balanced salt solution (HBSS). Concurrently, the effect of adding L: -cysteine and ascorbic acid (C&A) to each medium on the parasite viability was also compared. DMEM and RPMI 1640 showed higher viabilities as compared to PBS-A and HBSS. Only RPMI 1640 showed no statistical difference with the control medium for the first 4 h, however the ≥ 95% viability was only maintained for the first 2 h. The other protein-free media showed differences from the serum- and vitamin-free TYI-S-33 control media even after 1 h of incubation. When supplemented with C&A, all media were found to sustain higher trophozoite viabilities than those without the supplements. HBSS-C&A, DMEM-C&A, and RPMI 1640-C&A demonstrated no difference (P>0.05) in parasite viabilities when compared with the control medium throughout the 8-h incubation period. DMEM-C&A showed an eightfold increment in time duration of sustaining ≥ 95% parasite viability, i.e. 8 h, as compared to DMEM alone. Both RPMI 1640-C&A and HBSS-C&A revealed fourfold and threefold increments (i.e., 8 and 6 h, respectively), whereas PBS-A-C&A showed only one fold improvement (i.e., 2 h) as compared to the respective media without C&A. Thus, C&A-supplemented DMEM or RPMI are recommended for collection of ES products.
  2. Fulltext Analysis of Entamoeba histolytica excretory-secretory antigen and identification of a new potential diagnostic marker
    Wong WK, Tan ZN, Othman N, Lim BH, Mohamed Z, Olivos Garcia A, et al.
    Clin Vaccine Immunol, 2011 Nov;18(11):1913-7.
    PMID: 21918120 DOI: 10.1128/CVI.05356-11
    Serodiagnosis of amoebiasis remains the preferred method for diagnosis of amoebic liver abscess (ALA). However, the commercially available kits are problematic in areas of endemicity due to the persistently high background antibody titers. Human serum samples (n = 38) from patients with ALA who live in areas of endemicity were collected from Hospital Universiti Sains Malaysia during the period of 2008 to 2010. Western blots using excretory-secretory antigen (ESA) collected from axenically grown Entamoeba histolytica were probed with the above serum samples. Seven antigenic proteins of ESA with various reactivities were identified, i.e., 152 kDa, 131 kDa, 123 kDa, 110 kDa, 100 kDa, 82 kDa, and 76 kDa. However, only the 152-kDa and 110-kDa proteins showed sensitivities above 80% in the Western blot analysis. All the antigenic proteins showed undetectable cross-reactivity when probed with healthy human serum samples (n = 30) and serum samples from other infections (n = 33). From the matrix-assisted laser desorption ionization-two-stage time of flight (MALDI-TOF/TOF) analysis, the proteins were identified as heavy subunits of E. histolytica lectin and E. histolytica pyruvate phosphate dikinase, respectively. Use of the E. histolytica lectin for diagnosis of ALA has been well reported by researchers and is being used in commercialized kits. However, this is the first report on the potential use of pyruvate phosphate dikinase for diagnosis of ALA; thus, this molecule merits further evaluation on its diagnostic value using a larger panel of serum samples.
  3. Fulltext Evaluation of Entamoeba histolytica recombinant phosphoglucomutase protein for serodiagnosis of amoebic liver abscess
    Ning TZ, Kin WW, Noordin R, Cun ST, Chong FP, Mohamed Z, et al.
    BMC Infect Dis, 2013;13:144.
    PMID: 23514636 DOI: 10.1186/1471-2334-13-144
    Amoebic liver abscess (ALA) is the most frequent clinical presentation of extra-intestinal amoebiasis. The diagnosis of ALA is typically based on the developing clinical symptoms, characteristic changes on radiological imaging and serology. Numerous serological tests have been introduced for the diagnosis of ALA, either detecting circulating amoebic antigens or antibodies. However those tests show some pitfalls in their efficacy and/or the preparation of the tests are costly and tedious. The commercial IHA kit that used crude antigen was reported to be useful in diagnosis of ALA, however high antibody background in endemic areas may cause problems in its interpretation. Thus, discovery of well-defined antigen(s) is urgently needed to improve the weaknesses of current serodiagnostic tests.
  4. Fulltext Identification of Entamoeba histolytica trophozoites in fresh stool sample: comparison of three staining techniques and study on the viability period of the trophozoites
    Tan ZN, Wong WK, Nik Zairi Z, Abdullah B, Rahmah N, Zeehaida M, et al.
    Trop Biomed, 2010 Apr;27(1):79-88.
    PMID: 20562817 MyJurnal
    Entamoeba histolytica causes about 50 million infections worldwide with a death rate of over 100,000 annually. In endemic developing countries where resources are limited, microscopic examinations based on Wheatley trichrome staining is commonly used for diagnosis of intestinal amoebiasis. Other than being a time-consuming method, it must be performed promptly after stool collection as trophozoites disintegrate rapidly in faeces. The aim of this study was to compare the efficacies of Eosin-Y, Wheatley trichrome and Iodine stains in delineating the diagnostic features of the parasite, and subsequently to determine the suitable microscopy observation period for detection of erythrophagocytic and non-erythrophagocytic trophozoites spiked in semi-solid stool sample. Wheatley trichrome staining technique was performed using the standard method while the other two techniques were performed on the slides by mixing the respective staining solution with the spiked stool sample. One million of axenically cultured non-erythrophagocytic E. histolytica and erythrophagocytic E. histolytica were separately spiked into 2 g of fresh semisolid faeces. Percentage viability of the trophozoites in the spiked stool sample was determined at 30 minute intervals for eight hours using the 0.4% Trypan blue exclusion method. The results showed that Eosin-Y and Wheatley trichrome stained the karyosome and chromatin granules better as compared to Iodine stain. The percentage viability of non-erythrophagocytic trophozoites decreased faster than the erythrophagocytic form in the first 5 hours and both dropped to ~10% in the 6th hour spiked sample. In conclusion, Eosin-Y staining technique was found to be the easiest to perform, most rapid and as accurate as the commonly used Wheatley trichrome technique; Eosin-Y stained slide sealed with DPX could also be kept as a permanent record. A period not exceeding 6 hours after stool collection was found to be the most suitable in order to obtain good microscopy results of viable trophozoites.
  5. Parallel ELISAs using crude soluble antigen and excretory-secretory antigen for improved serodiagnosis of amoebic liver abscess
    Wong WK, Foo PC, Olivos-Garcia A, Noordin R, Mohamed Z, Othman N, et al.
    Acta Trop, 2017 Aug;172:208-212.
    PMID: 28506795 DOI: 10.1016/j.actatropica.2017.05.017
    Crude soluble antigen (CSA) produced from Entamoeba histolytica trophozoite is conventionally used for serodiagnosis of invasive amoebiasis. However, high background seropositivities by CSA-assay in endemic areas complicate the interpretation of positive result in clinical settings. Instead, incorporating a second assay which indicates active or recent infection into the routine amoebic serology could possibly complement the limitations of CSA-assay. Hence, the present study aimed to evaluate the diagnostic efficacies of indirect ELISAs using CSA and excretory-secretory antigen (ESA) for serodiagnosis of amoebic liver abscess (ALA). Reference standard for diagnosis of ALA at Hospital Universiti Sains Malaysia is based on clinical presentation, radiological imaging and positive indirect haemagglutination assay (titer ≥256). Five groups of human serum samples collected from the hospital included Group I - ALA diagnosed by the reference standard and pus aspirate analysis using real-time PCR (n=10), Group II - ALA diagnosed by the reference standard only (n=41), Group III - healthy control (n=45), Group IV - other diseases control (n=51) and Group V - other infectious diseases control (n=31). For serodiagnosis of ALA serum samples (Group I and II), CSA-ELISA showed sensitivities of 100% for both groups, while ESA-ELISA showed sensitivities of 100% and 88%, respectively. For serodiagnosis of non-ALA serum samples (Group III, IV and V), CSA-ELISA showed specificities of 91%, 75% and 100%, respectively; while ESA-ELISA showed specificities of 96%, 98% and 100%, respectively. Indirect ELISAs using CSA and ESA have shown distinct strength for serodiagnosis of ALA, in terms of sensitivity and specificity, respectively. In conclusion, parallel analysis by both assays improved the overall efficacies of amoebic serology as compared to either single assay.
  6. Latest Updates in Dengue Fever Therapeutics: Natural, Marine and Synthetic Drugs
    Hosseini S, Muñoz-Soto RB, Oliva-Ramírez J, Vázquez-Villegas P, Aghamohammadi N, Rodriguez-Garcia A, et al.
    Curr Med Chem, 2020;27(5):719-744.
    PMID: 29956614 DOI: 10.2174/0929867325666180629124709
    In this paper, we review the history of Dengue, the mechanism of infection, the molecular characteristics and components of Dengue, the mechanism of entry to the target cells, cyclization of the genome and replication process, as well as translation of the proteins for virus assembly. The major emphasis of this work is on natural products and plant extracts, which were used for as palliative or adjuvant treatment of Dengue. This review article also summarizes the latest findings in regards to the marine products as effective drugs to target different symptoms of Dengue. Furthermore, an update on synthetic drugs for treating Dengue is provided in this review. As a novel alternative, we describe monoclonal antibody therapy for Dengue management and treatment.
  7. Fulltext Polymethacrylate Coated Electrospun PHB Fibers as a Functionalized Platform for Bio-Diagnostics: Confirmation Analysis on the Presence of Immobilized IgG Antibodies against Dengue Virus
    Hosseini S, Azari P, Jiménez-Moreno MF, Rodriguez-Garcia A, Pingguan-Murphy B, Madou MJ, et al.
    Sensors (Basel), 2017 Oct 09;17(10).
    PMID: 28991214 DOI: 10.3390/s17102292
    In this article, a combination of far field electrospinning (FFES) and free-radical polymerization has been used to create a unique platform for protein immobilization via the physical attachment of biomolecules to the surface of the fiber mats. The large specific surface area of the fibers with its tailored chemistry provides a desirable platform for effective analyte-surface interaction. The detailed analysis of protein immobilization on a newly developed bio-receptive surface plays a vital role to gauge its advantages in bio-diagnostic applications. We relied on scanning electron microscopy (SEM), diameter range analysis, and X-ray photoelectron spectroscopy (XPS), along with thermal gravimetric analysis (TGA), water-in-air contact angle analysis (WCA), Fourier transform infrared spectroscopy (FTIR), and atomic force microscopy (AFM) to study our developed platforms and to provide valuable information regarding the presence of biomolecular entities on the surface. Detailed analyses of the fiber mats before and after antibody immobilization have shown obvious changes on the surface of the bioreceptive surface including: (i) an additional peak corresponding to the presence of an antibody in TGA analysis; (ii) extra FTIR peaks corresponding to the presence of antibodies on the coated fiber platforms; and (iii) a clear alteration in surface roughness recorded by AFM analysis. Confirmation analyses on protein immobilization are of great importance as they underlay substantial grounds for various biosensing applications.
  8. Fulltext Rationale, Design, and Baseline Characteristics of the EPICOR Asia Study (Long-tErm follow-uP of antithrombotic management patterns In Acute CORonary Syndrome patients in Asia)
    Huo Y, Lee SW, Sawhney JP, Kim HS, Krittayaphong R, Nhan VT, et al.
    Clin Cardiol, 2015 Sep;38(9):511-9.
    PMID: 26206158 DOI: 10.1002/clc.22431
    BACKGROUND: In-hospital and postdischarge mortality for acute coronary syndromes (ACS) vary across Asia and remain generally poorer than globally. The relationship between real-life antithrombotic management patterns (AMPs) and ACS-related outcomes in Asia is unclear.

    METHODS: EPICOR Asia (Long-tErm follow-uP of antithrombotic management patterns In acute CORonary syndrome patients in Asia) (NCT01361386) is a prospective, multinational, observational study of patients discharged after hospitalization for an ACS, with 2-year follow-up. The aim is to describe short- and long-term (up to 2 years post-index event) AMPs in patients hospitalized for ACS and to record clinical outcomes, healthcare resource use, and self-reported health status. Pre- and in-hospital management, AMPs, and associated outcomes, with particular focus on ischemic and bleeding events, will be recorded during the 2-year follow up.

    RESULTS: Between June 2011 and May 2012, 13 005 patients were enrolled. From these, 12 922 patients surviving an ACS (6616 with STEMI, 2570 with NSTEMI, and 3736 with UA) were eligible for inclusion from 219 hospitals across 8 countries and regions in Asia: China (n = 8214), Hong Kong (n = 177), India (n = 2468), Malaysia (n = 100), Singapore (n = 93), South Korea (n = 705), Thailand (n = 957), and Vietnam (n = 208).

    CONCLUSIONS: EPICOR Asia will provide information regarding clinical management and AMPs for ACS patients in Asia. Impact of AMPs on clinical outcomes, healthcare resource use, and self-reported health status both during hospitalization and up to 2 years after discharge will also be described.

  9. Fulltext Long-term antithrombotic management patterns in Asian patients with acute coronary syndrome: 2-year observations from the EPICOR Asia study
    Zheng B, Huo Y, Lee SW, Sawhney JPS, Kim HS, Krittayaphong R, et al.
    Clin Cardiol, 2020 Sep;43(9):999-1008.
    PMID: 32618009 DOI: 10.1002/clc.23400
    BACKGROUND: Despite guideline recommendations, dual antiplatelet therapy (DAPT) is frequently used for longer than 1 year after an acute coronary syndrome (ACS) event. In Asia, information on antithrombotic management patterns (AMPs), including DAPT post discharge, is sparse. This analysis evaluated real-world AMPs up to 2 years post discharge for ACS.

    HYPOTHESIS: There is wide variability in AMP use for ACS management in Asia.

    METHODS: EPICOR Asia (NCT01361386) is a prospective observational study of patients discharged after hospitalization for an ACS in eight countries/regions in Asia, followed up for 2 years. Here, we describe AMPs used and present an exploratory analysis of characteristics and outcomes in patients who received DAPT for ≤12 months post discharge compared with >12 months.

    RESULTS: Data were available for 12 922 patients; of 11 639 patients discharged on DAPT, 2364 (20.3%) received DAPT for ≤12 months and 9275 (79.7%) for >12 months, with approximately 60% still on DAPT at 2 years. Patients who received DAPT for >12 months were more likely to be younger, obese, lower Killip class, resident in India (vs China), and to have received invasive reperfusion. Clinical event rates during year 2 of follow-up were lower in patients with DAPT >12 vs ≤12 months, but no causal association can be implied in this non-randomized study.

    CONCLUSIONS: Most ACS patients remained on DAPT up to 1 year, in accordance with current guidelines, and over half remained on DAPT at 2 years post discharge. Patients not on DAPT at 12 months are a higher risk group requiring careful monitoring.

  10. Fulltext The clinical impact of using complex molecular profiling strategies in routine oncology practice
    Laes JF, Aftimos P, Barthelemy P, Bellmunt J, Berchem G, Camps C, et al.
    Oncotarget, 2018 Apr 17;9(29):20282-20293.
    PMID: 29755651 DOI: 10.18632/oncotarget.24757
    Molecular profiling and functional assessment of signalling pathways of advanced solid tumours are becoming increasingly available. However, their clinical utility in guiding patients' treatment remains unknown. Here, we assessed whether molecular profiling helps physicians in therapeutic decision making by analysing the molecular profiles of 1057 advanced cancer patient samples after failing at least one standard of care treatment using a combination of next-generation sequencing (NGS), immunohistochemistry (IHC) and other specific tests. The resulting information was interpreted and personalized treatments for each patient were suggested. Our data showed that NGS alone provided the oncologist with useful information in 10-50% of cases (depending on cancer type), whereas the addition of IHC/other tests increased extensively the usefulness of the information provided. Using internet surveys, we investigated how therapy recommendations influenced treatment choice of the oncologist. For patients who were still alive after the provision of the molecular information (76.8%), 60.4% of their oncologists followed report recommendations. Most treatment decisions (93.4%) were made based on the combination of NGS and IHC/other tests, and an approved drug- rather than clinical trial enrolment- was the main treatment choice. Most common reasons given by physicians to explain the non-adherence to recommendations were drug availability and cost, which remain barriers to personalised precision medicine. Finally, we observed that 27% of patients treated with the suggested therapies had an overall survival > 12 months. Our study demonstrates that the combination of NGS and IHC/other tests provides the most useful information in aiding treatment decisions by oncologists in routine clinical practice.
  11. Fulltext Surveillance of adverse events in the treatment of drug-resistant tuberculosis: A global feasibility study
    Akkerman O, Aleksa A, Alffenaar JW, Al-Marzouqi NH, Arias-Guillén M, Belilovski E, et al.
    Int J Infect Dis, 2019 Jun;83:72-76.
    PMID: 30953827 DOI: 10.1016/j.ijid.2019.03.036
    The World Health Organization launched a global initiative, known as aDSM (active TB drug safety monitoring and management) to better describe the safety profile of new treatment regimens for drug-resistant tuberculosis (TB) in real-world settings. However, comprehensive surveillance is difficult to implement in several countries. The aim of the aDSM project is to demonstrate the feasibility of implementing national aDSM registers and to describe the type and the frequency of adverse events (AEs) associated with exposure to the new anti-TB drugs. Following a pilot study carried out in 2016, official involvement of TB reference centres/countries into the project was sought and cases treated with bedaquiline- and/or delamanid-containing regimens were consecutively recruited. AEs were prospectively collected ensuring potential attribution of the AE to a specific drug based on its known safety profile. A total of 309 cases were fully reported from 41 centres in 27 countries (65% males; 268 treated with bedaquiline, 20 with delamanid, and 21 with both drugs) out of an estimated 781 cases the participating countries had committed to report by the first quarter of 2019.
  12. Adaptation of sea turtles to climate warming: Will phenological responses be sufficient to counteract changes in reproductive output?
    Fuentes MMPB, Santos AJB, Abreu-Grobois A, Briseño-Dueñas R, Al-Khayat J, Hamza S, et al.
    Glob Chang Biol, 2024 Jan;30(1):e16991.
    PMID: 37905464 DOI: 10.1111/gcb.16991
    Sea turtles are vulnerable to climate change since their reproductive output is influenced by incubating temperatures, with warmer temperatures causing lower hatching success and increased feminization of embryos. Their ability to cope with projected increases in ambient temperatures will depend on their capacity to adapt to shifts in climatic regimes. Here, we assessed the extent to which phenological shifts could mitigate impacts from increases in ambient temperatures (from 1.5 to 3°C in air temperatures and from 1.4 to 2.3°C in sea surface temperatures by 2100 at our sites) on four species of sea turtles, under a "middle of the road" scenario (SSP2-4.5). Sand temperatures at sea turtle nesting sites are projected to increase from 0.58 to 4.17°C by 2100 and expected shifts in nesting of 26-43 days earlier will not be sufficient to maintain current incubation temperatures at 7 (29%) of our sites, hatching success rates at 10 (42%) of our sites, with current trends in hatchling sex ratio being able to be maintained at half of the sites. We also calculated the phenological shifts that would be required (both backward for an earlier shift in nesting and forward for a later shift) to keep up with present-day incubation temperatures, hatching success rates, and sex ratios. The required shifts backward in nesting for incubation temperatures ranged from -20 to -191 days, whereas the required shifts forward ranged from +54 to +180 days. However, for half of the sites, no matter the shift the median incubation temperature will always be warmer than the 75th percentile of current ranges. Given that phenological shifts will not be able to ameliorate predicted changes in temperature, hatching success and sex ratio at most sites, turtles may need to use other adaptive responses and/or there is the need to enhance sea turtle resilience to climate warming.
  13. Fulltext Female chromosome X mosaicism is age-related and preferentially affects the inactivated X chromosome
    Machiela MJ, Zhou W, Karlins E, Sampson JN, Freedman ND, Yang Q, et al.
    Nat Commun, 2016 06 13;7:11843.
    PMID: 27291797 DOI: 10.1038/ncomms11843
    To investigate large structural clonal mosaicism of chromosome X, we analysed the SNP microarray intensity data of 38,303 women from cancer genome-wide association studies (20,878 cases and 17,425 controls) and detected 124 mosaic X events >2 Mb in 97 (0.25%) women. Here we show rates for X-chromosome mosaicism are four times higher than mean autosomal rates; X mosaic events more often include the entire chromosome and participants with X events more likely harbour autosomal mosaic events. X mosaicism frequency increases with age (0.11% in 50-year olds; 0.45% in 75-year olds), as reported for Y and autosomes. Methylation array analyses of 33 women with X mosaicism indicate events preferentially involve the inactive X chromosome. Our results provide further evidence that the sex chromosomes undergo mosaic events more frequently than autosomes, which could have implications for understanding the underlying mechanisms of mosaic events and their possible contribution to risk for chronic diseases.
  14. Fulltext Guidelines for the use and interpretation of assays for monitoring autophagy (4th edition)1
    Klionsky DJ, Abdel-Aziz AK, Abdelfatah S, Abdellatif M, Abdoli A, Abel S, et al.
    Autophagy, 2021 Jan;17(1):1-382.
    PMID: 33634751 DOI: 10.1080/15548627.2020.1797280
    In 2008, we published the first set of guidelines for standardizing research in autophagy. Since then, this topic has received increasing attention, and many scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Thus, it is important to formulate on a regular basis updated guidelines for monitoring autophagy in different organisms. Despite numerous reviews, there continues to be confusion regarding acceptable methods to evaluate autophagy, especially in multicellular eukaryotes. Here, we present a set of guidelines for investigators to select and interpret methods to examine autophagy and related processes, and for reviewers to provide realistic and reasonable critiques of reports that are focused on these processes. These guidelines are not meant to be a dogmatic set of rules, because the appropriateness of any assay largely depends on the question being asked and the system being used. Moreover, no individual assay is perfect for every situation, calling for the use of multiple techniques to properly monitor autophagy in each experimental setting. Finally, several core components of the autophagy machinery have been implicated in distinct autophagic processes (canonical and noncanonical autophagy), implying that genetic approaches to block autophagy should rely on targeting two or more autophagy-related genes that ideally participate in distinct steps of the pathway. Along similar lines, because multiple proteins involved in autophagy also regulate other cellular pathways including apoptosis, not all of them can be used as a specific marker for bona fide autophagic responses. Here, we critically discuss current methods of assessing autophagy and the information they can, or cannot, provide. Our ultimate goal is to encourage intellectual and technical innovation in the field.
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