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  1. Fulltext Plasmodium knowlesi in travellers, update 2014
    Müller M, Schlagenhauf P
    Int J Infect Dis, 2014 May;22:55-64.
    PMID: 24631521 DOI: 10.1016/j.ijid.2013.12.016
    Since the initial discovery of Plasmodium knowlesi in Malaysia, cases have been reported from several neighbouring countries. Tourism has also resulted in an increasing number of cases diagnosed in Europe, America, and Oceania. In this review we focus on the risk of the travel-associated acquisition of P. knowlesi malaria.
  2. A functional gene-array analysis of microbial communities settling on microplastics in a peat-draining environment
    Rahman I, Mujahid A, Palombo EA, Müller M
    Mar Pollut Bull, 2021 May;166:112226.
    PMID: 33711605 DOI: 10.1016/j.marpolbul.2021.112226
    Concerns about microplastic (MP) pollution arise from the rafting potential of these durable particles which potentially propagate harmful chemicals and bacteria across wide spatial gradients. While many studies have been conducted in the marine environment, knowledge of MPs in coastal and freshwater systems is limited. For this study, we exposed two MPs (polyethylene terephthalate and polylactic acid) to the undisturbed peat-draining Maludam River in Malaysia, for 6 months. The microbial communities on these MPs and the surrounding water were sequenced by MiSeq, while the genetic responses of these communities were assessed by GeoChip 5.0S. Microbial communities were dominated by the phyla Proteobacteria, Acidobacteria and Actinobacteria. Metabolic processes involved with carbon, nitrogen, sulfur, metal homeostasis, organic remediation and virulence had significantly different gene expression among the communities on MPs and in the surrounding water. Our study is the first to look at changes in gene expression of whole plastisphere communities.
  3. Fulltext The impact of omalizumab on paid and unpaid work productivity among severe Japanese cedar pollinosis (JCP) patients
    Müller M, Igarashi A, Hashiguchi K, Kappel M, Paolini F, Yoshisue H, et al.
    J Med Econ, 2022 1 25;25(1):220-229.
    PMID: 35072591 DOI: 10.1080/13696998.2022.2033051
    AIMS: Japanese cedar pollinosis (JCP) is a form of seasonal allergic rhinitis that affects 38.8% of the Japanese population. Particularly severe and most severe symptoms among JCP patients can lead to impairments of paid work productivity and unpaid work activities. Indeed, the current standard of care (SoC) is not always able to relieve these symptoms. Omalizumab, a novel JCP treatment recently approved in Japan, provides an effective add-on therapy to the SoC. This study estimates the effect of omalizumab on paid and unpaid work activities (i.e. its social impact) in patients with severe and most severe JCP symptoms in Japan.

    METHODS: The impact of omalizumab was estimated through a one-year static cohort model using the Work Productivity and Activity Impairment Allergy Specific (WPAI-AS) questionnaire derived from a clinical trial on omalizumab enrolling patients with severe and most severe JCP symptoms, which had been conducted in Japan. This effect was quantified using Japanese official statistics on employment and time use. The human capital approach and the proxy good approach were employed to monetize paid and unpaid work activities, respectively. A sensitivity analysis was implemented to account for modeling structural uncertainties.

    RESULTS: Our results show that the use of omalizumab might reduce the paid and unpaid work productivity losses due to severe and most severe JCP by nearly one-third. In the severe symptom period of three weeks, 36.6 million hours of lost paid and unpaid work hours could be avoided, which sums up to a monetized productivity loss of 728.3 million USD.

    CONCLUSIONS: Omalizumab could provide substantial benefits in terms of paid and unpaid work activities in patients with severe and most severe JCP. Our results also highlight the importance of considering unpaid work in estimating productivity costs due to poor health.

  4. Fulltext Investigating quorum-quenching marine bacilli as potential biocontrol agents for protection of shrimps against Early Mortality Syndrome (EMS)
    Müller M, Spiers AJ, Tan A, Mujahid A
    Sci Rep, 2023 Mar 12;13(1):4095.
    PMID: 36907954 DOI: 10.1038/s41598-023-31197-4
    Early Mortality Syndrome (EMS) has been a major problem for shrimp aquaculture in Southeast Asia due to its epizootic prevalence within the region since the first reported case in 2009. This study explores the application of halophilic marine bacilli isolated from coral mucus and their quorum-quenching abilities as potential biocontrol agents in aquaculture systems to combat the causative agent of EMS, Vibrio parahaemolyticus. N-acylhomoserine lactone (AHL)-degrading (AiiA) activity was first screened by PCR then confirmed by bio-reporter assay, and a combination of 16S rDNA sequence analysis and quantitative phenotype assays including biofilm-formation and temperature-growth responses were used to demonstrate diversity amongst these quorum-quenching isolates. Three phenotypically distinct strains showing notable potential were chosen to undergo co-cultivation as a method for strain improvement via long term exposure to the pathogenic V. parahaemolyticus. The novel approach taken led to significant improvements in antagonism and quorum quenching activities as compared to the ancestral wild-type strains and offers a potential solution as well as pathway to improve existing beneficial microbes for one of the most pressing issues in shrimp aquacultures worldwide.
  5. Fulltext The impact of disturbed peatlands on river outgassing in Southeast Asia
    Wit F, Müller D, Baum A, Warneke T, Pranowo WS, Müller M, et al.
    Nat Commun, 2015;6:10155.
    PMID: 26670925 DOI: 10.1038/ncomms10155
    River outgassing has proven to be an integral part of the carbon cycle. In Southeast Asia, river outgassing quantities are uncertain due to lack of measured data. Here we investigate six rivers in Indonesia and Malaysia, during five expeditions. CO2 fluxes from Southeast Asian rivers amount to 66.9 ± 15.7 Tg C per year, of which Indonesia releases 53.9 ± 12.4 Tg C per year. Malaysian rivers emit 6.2 ± 1.6 Tg C per year. These moderate values show that Southeast Asia is not the river outgassing hotspot as would be expected from the carbon-enriched peat soils. This is due to the relatively short residence time of dissolved organic carbon (DOC) in the river, as the peatlands, being the primary source of DOC, are located near the coast. Limitation of bacterial production, due to low pH, oxygen depletion or the refractory nature of DOC, potentially also contributes to moderate CO2 fluxes as this decelerates decomposition.
  6. Fulltext A comparative UHPLC-Q/TOF-MS-based eco-metabolomics approach reveals temperature adaptation of four Nepenthes species
    Wong C, Ling YS, Wee JLS, Mujahid A, Müller M
    Sci Rep, 2020 12 14;10(1):21861.
    PMID: 33318532 DOI: 10.1038/s41598-020-78873-3
    Nepenthes, as the largest family of carnivorous plants, is found with an extensive geographical distribution throughout the Malay Archipelago, specifically in Borneo, Philippines, and Sumatra. Highland species are able to tolerate cold stress and lowland species heat stress. Our current understanding on the adaptation or survival mechanisms acquired by the different Nepenthes species to their climatic conditions at the phytochemical level is, however, limited. In this study, we applied an eco-metabolomics approach to identify temperature stressed individual metabolic fingerprints of four Nepenthes species: the lowlanders N. ampullaria, N. rafflesiana and N. northiana, and the highlander N. minima. We hypothesized that distinct metabolite regulation patterns exist between the Nepenthes species due to their adaptation towards different geographical and altitudinal distribution. Our results revealed not only distinct temperature stress induced metabolite fingerprints for each Nepenthes species, but also shared metabolic response and adaptation strategies. The interspecific responses and adaptation of N. rafflesiana and N. northiana likely reflected their natural habitat niches. Moreover, our study also indicates the potential of lowlanders, especially N. ampullaria and N. rafflesiana, to produce metabolites needed to deal with increased temperatures, offering hope for the plant genus and future adaption in times of changing climate.
  7. Biosorption of copper by endophytic fungi isolated from Nepenthes ampullaria
    Wong C, Tan LT, Mujahid A, Lihan S, Wee JLS, Ting LF, et al.
    Lett Appl Microbiol, 2018 Oct;67(4):384-391.
    PMID: 29998586 DOI: 10.1111/lam.13049
    Copper (Cu) tolerance was observed by endophytic fungi isolated from the carnivorous plant Nepenthes ampullaria (collected at an anthropogenically affected site, Kuching city; and a pristine site; Heart of Borneo). The fungal isolates, capable of tolerating Cu up to 1000 ppm (11 isolates in total), were identified through molecular method [internal transcribed spacer 4+5 (ITS4+5); ITS1+NL4; β-tubulin region using Bt2a + Bt2b], and all of them grouped with Diaporthe, Nigrospora, and Xylaria. A Cu biosorption study was then carried out using live and dead biomass of the 11 fungal isolates. The highest biosorption capacity of using live biomass was achieved by fungal isolates Xylaria sp. NA40 (73·26 ± 1·61 mg Cu per g biomass) and Diaporthe sp. NA41 (72·65 ± 2·23 mg Cu per g biomass), NA27 (59·81 ± 1·15 mg Cu per g biomass) and NA28 (56·85 ± 4·23 mg Cu per g biomass). The fungal isolate Diaporthe sp. NA41 also achieved the highest biosorption capacity of 59·33 ± 0·15 mg g-1 using dead biomass. The living biomass possessed a better biosorption capacity than the dead biomass (P 
  8. Chemotactic response of Vibrio coralliilyticus to mucus from various coral species
    Rahman I, Al-Bar AA, Richard FS, Müller M, Mujahid A
    Can J Microbiol, 2021 Jul;67(7):548-552.
    PMID: 33417515 DOI: 10.1139/cjm-2020-0287
    Vibrio coralliilyticus, a prominent pathogenic bacteria, is known to cause tissue damage in the coral Pocillopora damicornis and is attracted towards the coral via chemotaxis. However, the potential of V. coralliilyticus to infect most of the other coral hosts via chemotaxis is unknown. In this study, we used capillary assays to quantify the chemotactic response of V. coralliilyticus to the mucus of four tank-cultivated coral species (Cataphyllia jardine, Mussidae sp., Nemenzophyllia turbida, and Euphyllia ancora), and mucus from three wild coral species (Acropora sp., Porites sp., and Montipora sp.). The bacteria showed a positive chemotactic response to each coral mucus tested, with the highest response recorded to the mucus of Acropora sp. and the lowest response to the mucus of Montipora sp. A microfluidic chip was then used to assess the chemotactic preference of V. coralliilyticus to the mucus of the tank cultivated corals. Here too, the bacterium showed positive response, but with a slightly different ranking order. The strong chemotactic response of V. coralliilyticus towards the mucus tested could indicate a broader host range of V. coralliilyticus, and by extension, indicate a threat to weakened coral reefs worldwide.
  9. Increased transfer of trace metals and Vibrio sp. from biodegradable microplastics to catfish Clarias gariepinus
    Jang FH, Wong C, Choo J, Aun Sia ES, Mujahid A, Müller M
    Environ Pollut, 2022 Apr 01;298:118850.
    PMID: 35041899 DOI: 10.1016/j.envpol.2022.118850
    Microplastic ingestion has been documented in various aquatic species. This causes physical damage, and additionally contaminated microplastics transfer attached pollutants and microbial pathogens to ingesting organisms. Continued metal accumulation can lead to toxicity and adverse health effects; attached microbial pathogens can cause dysbiosis - which lowers host immunity and promotes infections. Catfish, Clarias gariepinus, are a major food source in Southeast Asia, a hotspot of plastic pollution. This study aimed to quantify the transfer of the trace metals copper (Cu) and lead (Pb) -at environmentally relevant concentrations-from microplastics (polyamide 12, PA12, and polylactic acid, PLA) to catfish. Fish were reared for three months and exposed to seven different combinations of feed, supplemented with plastics and metals. At monthly intervals, fish gills, intestines, liver, and edible muscles were analysed for Cu and Pb concentrations using ICP-OES, and the intestines content assessed for Vibrio sp.. Our results showed that biodegradable PLA transferred higher amounts of metals to catfish than expected and also led to increased Vibrio counts in the intestines compared to PA12. Trace metal accumulation was significantly different in varying tissues, with highest concentrations observed in the gills, followed by liver, intestines, and lastly edible muscles. The results of this study further support the existing evidence that microplastics act as efficient shuttles to concentrate and transfer metals. They also indicate that their uptake can cause dysbiosis (increased numbers of Vibrio sp.). Most importantly, however, our study highlights that biodegradable polymers, such as PLA, could actually pose a greater environmental threat when ingested compared to the more common polymers such as PA12.
  10. Fulltext Comparison of learning models to predict LDPE, PET, and ABS concentrations in beach sediment based on spectral reflectance
    Huda FR, Richard FS, Rahman I, Moradi S, Hua CTY, Wanwen CAS, et al.
    Sci Rep, 2023 Apr 17;13(1):6258.
    PMID: 37069310 DOI: 10.1038/s41598-023-33207-x
    Microplastic (MP) contamination on land has been estimated to be 32 times higher than in the oceans, and yet there is a distinct lack of research on soil MPs compared to marine MPs. Beaches are bridges between land and ocean and present equally understudied sites of microplastic pollution. Visible-near-infrared (vis-NIR) has been applied successfully for the measurement of reflectance and prediction of low-density polyethylene (LDPE), polyethylene terephthalate (PET), and polyvinyl chloride (PVC) concentrations in soil. The rapidity and precision associated with this method make vis-NIR promising. The present study explores PCA regression and machine learning approaches for developing learning models. First, using a spectroradiometer, the spectral reflectance data was measured from treated beach sediment spiked with virgin microplastic pellets [LDPE, PET, and acrylonitrile butadiene styrene (ABS)]. Using the recorded spectral data, predictive models were developed for each microplastic using both the approaches. Both approaches generated models of good accuracy with R2 values greater than 0.7, root mean squared error (RMSE) values less than 3 and mean absolute error (MAE) 
  11. Fulltext Insights into the Cultured Bacterial Fraction of Corals
    Sweet M, Villela H, Keller-Costa T, Costa R, Romano S, Bourne DG, et al.
    mSystems, 2021 Jun 29;6(3):e0124920.
    PMID: 34156291 DOI: 10.1128/mSystems.01249-20
    Bacteria associated with coral hosts are diverse and abundant, with recent studies suggesting involvement of these symbionts in host resilience to anthropogenic stress. Despite their putative importance, the work dedicated to culturing coral-associated bacteria has received little attention. Combining published and unpublished data, here we report a comprehensive overview of the diversity and function of culturable bacteria isolated from corals originating from tropical, temperate, and cold-water habitats. A total of 3,055 isolates from 52 studies were considered by our metasurvey. Of these, 1,045 had full-length 16S rRNA gene sequences, spanning 138 formally described and 12 putatively novel bacterial genera across the Proteobacteria, Firmicutes, Bacteroidetes, and Actinobacteria phyla. We performed comparative genomic analysis using the available genomes of 74 strains and identified potential signatures of beneficial bacterium-coral symbioses among the strains. Our analysis revealed >400 biosynthetic gene clusters that underlie the biosynthesis of antioxidant, antimicrobial, cytotoxic, and other secondary metabolites. Moreover, we uncovered genomic features-not previously described for coral-bacterium symbioses-potentially involved in host colonization and host-symbiont recognition, antiviral defense mechanisms, and/or integrated metabolic interactions, which we suggest as novel targets for the screening of coral probiotics. Our results highlight the importance of bacterial cultures to elucidate coral holobiont functioning and guide the selection of probiotic candidates to promote coral resilience and improve holistic and customized reef restoration and rehabilitation efforts. IMPORTANCE Our paper is the first study to synthesize currently available but decentralized data of cultured microbes associated with corals. We were able to collate 3,055 isolates across a number of published studies and unpublished collections from various laboratories and researchers around the world. This equated to 1,045 individual isolates which had full-length 16S rRNA gene sequences, after filtering of the original 3,055. We also explored which of these had genomes available. Originally, only 36 were available, and as part of this study, we added a further 38-equating to 74 in total. From this, we investigated potential genetic signatures that may facilitate a host-associated lifestyle. Further, such a resource is an important step in the selection of probiotic candidates, which are being investigated for promoting coral resilience and potentially applied as a novel strategy in reef restoration and rehabilitation efforts. In the spirit of open access, we have ensured this collection is available to the wider research community through the web site http://isolates.reefgenomics.org/ with the hope many scientists across the globe will ask for access to these cultures for future studies.
  12. Spatial-temporal variations in surface ozone over Ushuaia and the Antarctic region: observations from in situ measurements, satellite data, and global models
    Nadzir MSM, Ashfold MJ, Khan MF, Robinson AD, Bolas C, Latif MT, et al.
    Environ Sci Pollut Res Int, 2018 Jan;25(3):2194-2210.
    PMID: 29116536 DOI: 10.1007/s11356-017-0521-1
    The Antarctic continent is known to be an unpopulated region due to its extreme weather and climate conditions. However, the air quality over this continent can be affected by long-lived anthropogenic pollutants from the mainland. The Argentinian region of Ushuaia is often the main source area of accumulated hazardous gases over the Antarctic Peninsula. The main objective of this study is to report the first in situ observations yet known of surface ozone (O3) over Ushuaia, the Drake Passage, and Coastal Antarctic Peninsula (CAP) on board the RV Australis during the Malaysian Antarctic Scientific Expedition Cruise 2016 (MASEC'16). Hourly O3 data was measured continuously for 23 days using an EcoTech O3 analyzer. To understand more about the distribution of surface O3 over the Antarctic, we present the spatial and temporal of surface O3 of long-term data (2009-2015) obtained online from the World Meteorology Organization of World Data Centre for greenhouse gases (WMO WDCGG). Furthermore, surface O3 satellite data from the free online NOAA-Atmospheric Infrared Sounder (AIRS) database and online data assimilation from the European Centre for Medium-Range Weather Forecasts (ECMWF)-Monitoring Atmospheric Composition and Climate (MACC) were used. The data from both online products are compared to document the data sets and to give an indication of its quality towards in situ data. Finally, we used past carbon monoxide (CO) data as a proxy of surface O3 formation over Ushuaia and the Antarctic region. Our key findings were that the surface O3 mixing ratio during MASEC'16 increased from a minimum of 5 ppb to ~ 10-13 ppb approaching the Drake Passage and the Coastal Antarctic Peninsula (CAP) region. The anthropogenic and biogenic O3 precursors from Ushuaia and the marine region influenced the mixing ratio of surface O3 over the Drake Passage and CAP region. The past data from WDCGG showed that the annual O3 cycle has a maximum during the winter of 30 to 35 ppb between June and August and a minimum during the summer (January to February) of 10 to 20 ppb. The surface O3 mixing ratio during the summer was controlled by photochemical processes in the presence of sunlight, leading to the depletion process. During the winter, the photochemical production of surface O3 was more dominant. The NOAA-AIRS and ECMWF-MACC analysis agreed well with the MASEC'16 data but twice were higher during the expedition period. Finally, the CO past data showed the surface O3 mixing ratio was influenced by the CO mixing ratio over both the Ushuaia and Antarctic regions. Peak surface O3 and CO hourly mixing ratios reached up to ~ 38 ppb (O3) and ~ 500 ppb (CO) over Ushuaia. High CO over Ushuaia led to the depletion process of surface O3 over the region. Monthly CO mixing ratio over Antarctic (South Pole) were low, leading to the production of surface O3 over the Antarctic region.
  13. Corrigendum to "Priorities to inform research on marine plastic pollution in Southeast Asia" [Sci. Total Environ. volume 841 (2022) Article 156704]
    Omeyer LCM, Duncan EM, Aiemsomboon K, Beaumont N, Bureekul S, Cao B, et al.
    Sci Total Environ, 2023 Jan 20;857(Pt 3):159595.
    PMID: 36308807 DOI: 10.1016/j.scitotenv.2022.159595
  14. Denial of long-term issues with agriculture on tropical peatlands will have devastating consequences
    Wijedasa LS, Jauhiainen J, Könönen M, Lampela M, Vasander H, Leblanc MC, et al.
    Glob Chang Biol, 2017 03;23(3):977-982.
    PMID: 27670948 DOI: 10.1111/gcb.13516
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