Displaying publications 1 - 20 of 176 in total

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  1. Doughty MJ
    Clin Exp Optom, 2014 May;97(3):256-63.
    PMID: 24405014 DOI: 10.1111/cxo.12127
    PURPOSE: The aim was to assess the morphology of the Asian corneal endothelium, particularly the index of polymegethism and its relationship to endothelial cell density assessments.
    METHODS: The central regions of the corneal endothelium of 72 healthy, normal weight, non-contact lens wearers were assessed by non-contact specular microscopy. There were six groups of persons, aged between 18 and 27 years, whose ethnic origins were self-reported as Asian (Mainland China, Hong Kong, India, Malaysia, Pakistan or other Asian groups). Single images including at least 100 contiguous cells were obtained from each subject and were processed by planimetry after manual border marking to minimise errors. Calculations were made of the coefficient of variation of cell area (COV; polymegethism) as well as the endothelial cell density and percentage of six-sided cells.
    RESULTS: The COV values ranged from 18 to 30.4 per cent (group mean 24.5 ± 2.8 per cent). The corneas had essentially normal thickness (0.530 ± 0.026 mm), with the endothelia showing a high percentage of six-sided cells (66.3 ± 7.1 per cent) and none showing even mild signs of polymegethism. Endothelial cell density estimates based on average cell areas ranged from 2,020 to 3,623 cells per mm(2) and from 2,157 to 3,835 with calculations based on individual cell areas. The difference between the two estimates of endothelial cell density was strongly related to the coefficient of variation (r = 0.765).
    CONCLUSIONS: This result is consistent with several older reports indicating that it is uncommon to find polymegethism in healthy young adult Asian individuals. Nonetheless, even low coefficient of variation values can substantially affect the estimations of the cell density.
    KEYWORDS: Asian; cornea; endothelium; human; polymegathism
  2. Reid MJC
    Am J Primatol, 2020 08;82(8):e23161.
    PMID: 32583538 DOI: 10.1002/ajp.23161
    Year 2020 has brought the greatest global pandemic to hit the world since the end of the First World War. The severe acute respiratory syndrome coronavirus 2 and the resulting disease named coronavirus disease 2019 has brought the world to its knees both financially and medically. The American Society of Primatologists has postponed their annual meetings from the end of May 2020 until the end of September 2020, while the International Primatological Society have postponed their biennial congress from August 2020 to August 2021, which has also resulted in their 2022 meetings in Malaysia being pushed back until 2023. Here, I explore the potential dangers of pursuing any primate fieldwork during this pandemic on our study species, their ecosystems, and local peoples. I believe that the risk of bringing this virus into our study ecosystems is too great and that primatologists should cancel all field research until the pandemic ends or a vaccine/reliable treatment is widely available. This is the year we all must become One Health practitioners!
  3. Adie H, Lawes MJ
    Biol Rev Camb Philos Soc, 2023 Apr;98(2):643-661.
    PMID: 36444419 DOI: 10.1111/brv.12923
    Tree species of Eurasian broadleaved forest possess two divergent trait syndromes with contrasting patterns of resource allocation adapted to different selection environments: short-stature basal resprouters that divert resources to a bud bank adapted to frequent and severe disturbances such as fire and herbivory, and tall trees that delay reproduction by investing in rapid height growth to escape shading. Drawing on theory developed in savanna ecosystems, we propose a conceptual framework showing that the possession of contrasting trait syndromes is essential for the persistence of broadleaved trees in an open ecosystem that burns. Consistent with this hypothesis, trees of modern Eurasian broadleaved forest bear a suite of traits that are adaptive to surface and crown-fire regimes. We contend that limited opportunities in grassland restricts recruitment to disturbance-free refugia, and en masse establishment creates a wooded environment where shade limits the growth of light-demanding savanna plants. Rapid height growth, which involves investment in structural support and the switch from a multi-stemmed to a monopodial growth form, is adaptive in this shaded environment. Although clustering reduces surface fuel loads, these establishment nuclei are vulnerable to high-intensity crown fires. The lethal effects of canopy fire are avoided by seasonal leaf shedding, and aerial resprouting enhances rapid post-fire recovery of photosynthetic capacity. While these woody formations satisfy the structural definition of forest, their constituents are clearly derived from savanna. Contrasting trait syndromes thus represent the shift from consumer to resource regulation in savanna ecosystems. Consistent with global trends, the diversification of most contemporary broadleaved taxa coincided with the spread of grasslands, a surge in fire activity and a decline in wooded ecosystems in the late Miocene-Pliocene. Recognition that Eurasian broadleaved forest has savanna origins and persists as an alternative state with adjacent grassy ecosystems has far-reaching management implications in accordance with functional rather than structural criteria. Shade is a severe constraint to the regeneration and growth of both woody and herbaceous growth forms in consumer-regulated ecosystems. However, these ecosystems are highly resilient to disturbance, an essential process that maintains diversity especially among the species-rich herbaceous component that is vulnerable to shading when consumer behaviour is altered.
  4. O'Brien MJ, Ong R, Reynolds G
    Glob Chang Biol, 2017 10;23(10):4235-4244.
    PMID: 28192618 DOI: 10.1111/gcb.13658
    Precipitation patterns are changing across the globe causing more severe and frequent drought for many forest ecosystems. Although research has focused on the resistance of tree populations and communities to these novel precipitation regimes, resilience of forests is also contingent on recovery following drought, which remains poorly understood, especially in aseasonal tropical forests. We used rainfall exclusion shelters to manipulate the interannual frequency of drought for diverse seedling communities in a tropical forest and assessed resistance, recovery and resilience of seedling growth and mortality relative to everwet conditions. We found seedlings exposed to recurrent periods of drought altered their growth rates throughout the year relative to seedlings in everwet conditions. During drought periods, seedlings grew slower than seedlings in everwet conditions (i.e., resistance phase) while compensating with faster growth after drought (i.e., recovery phase). However, the response to frequent drought was species dependent as some species grew significantly slower with frequent drought relative to everwet conditions while others grew faster with frequent drought due to overcompensating growth during the recovery phase. In contrast, mortality was unrelated to rainfall conditions and instead correlated with differences in light. Intra-annual plasticity of growth and increased annual growth of some species led to an overall maintenance of growth rates of tropical seedling communities in response to more frequent drought. These results suggest these communities can potentially adapt to predicted climate change scenarios and that plasticity in the growth of species, and not solely changes in mortality rates among species, may contribute to shifts in community composition under drought.
  5. Md Rezali KA, Griffin MJ
    Ergonomics, 2018 Sep;61(9):1246-1258.
    PMID: 29628001 DOI: 10.1080/00140139.2018.1462407
    This study investigated effects of applied force on the apparent mass of the hand, the dynamic stiffness of glove materials and the transmission of vibration through gloves to the hand. For 10 subjects, 3 glove materials and 3 contact forces, apparent masses and glove transmissibilities were measured at the palm and at a finger at frequencies in the range 5-300 Hz. The dynamic stiffnesses of the materials were also measured. With increasing force, the dynamic stiffnesses of the materials increased, the apparent mass at the palm increased at frequencies greater than the resonance and the apparent mass at the finger increased at low frequencies. The effects of force on transmissibilities therefore differed between materials and depended on vibration frequency, but changes in apparent mass and dynamic stiffness had predictable effects on material transmissibility. Depending on the glove material, the transmission of vibration through a glove can be increased or decreased when increasing the applied force. Practitioner summary: Increasing the contact force (i.e. push force or grip force) can increase or decrease the transmission of vibration through a glove. The vibration transmissibilities of gloves should be assessed with a range of contact forces to understand their likely influence on the exposure of the hand and fingers to vibration.
  6. Preece ND, van Oosterzee P, Lawes MJ
    J Environ Manage, 2023 Jun 15;336:117645.
    PMID: 36871451 DOI: 10.1016/j.jenvman.2023.117645
    Successful cost-effective reforestation plantings depend substantially on maximising sapling survival from the time of planting, yet in reforestation programs remarkably little attention is given to management of saplings at the planting stage and to planting methods used. Critical determinants of sapling survival include their vigour and condition when planted, the wetness of the soil into which saplings are planted, the trauma of transplant shock from nursery to natural field soils, and the method and care taken during planting. While some determinants are outside planters' control, careful management of specific elements associated with outplanting can significantly lessen transplanting shock and improve survival rates. Results from three reforestation experiments designed to examine cost-effective planting methods in the Australian wet tropics provided the opportunity to examine the effects of specific planting treatments, including (1) watering regime prior to planting, (2) method of planting and planter technique, and (3) site preparation and maintenance, on sapling survival and establishment. Focusing on sapling root moisture and physical protection during planting improved sapling survival by at least 10% (>91% versus 81%) at 4 months. Survival rates of saplings under different planting treatments were reflected in longer-term survival of trees at 18-20 months, differing from a low of 52% up to 76-88%. This survival effect was evident more than 6 years after planting. Watering saplings immediately prior to planting, careful planting using a forester's planting spade in moist soil and suppressing grass competition using appropriate herbicides were critical to improved plant survival.
  7. Michael JM, Hayakawa JM
    World Health Forum, 1994;15(3):282-3.
    PMID: 7945762
    In January 1984, the Asia-Pacific Academic Consortium for Public Health (APACPH) was established, bringing together 5 schools of public health with the objectives: to raise the quality of professional education in public health; to enhance the knowledge and skills of health workers through joint projects; to solve health problems through closer links with each other and with ministries of health; to increase opportunities for graduate students through curriculum development; and to make child survival a major priority. The Consortium now comprises 31 academic institutions or units in 16 countries, and is supported by UNICEF, The World Health Organization, the China Medical Board of New York, and the governments of Japan and Malaysia. During 1985-1992, it also received major support from the United States through the US Agency for International Development and the University of Hawaii. During the past 10 years, APACPH has carried out such activities as setting up a data bank on the programs of its members, assessing public health problems, designing new curriculum and systems for service delivery, facilitating information and faculty exchanges, and running workshops for academic administrators. It has also organized conferences on the impact of urbanization on health, aging, child survival, AIDS, and occupational health. Since 1987 it has published the Asia-Pacific Journal of Public Health, the only English language journal on public health issues in the Asia and Pacific region, which will feature work being done by non-English-speaking researchers. Emphasis in the coming years will be placed on setting common standards for teaching and research, so that members can make more use of each other's programs. It is hoped that membership of the Consortium will continue to expand. A particular concern will be to focus more resources on preventive care rather than curative.
  8. Miller J, Sweet MJ, Wood E, Bythell J
    PeerJ, 2015;3:e1391.
    PMID: 26732905 DOI: 10.7717/peerj.1391
    Two of the most significant threats to coral reefs worldwide are bleaching and disease. However, there has been a scarcity of research on coral disease in South-East Asia, despite the high biodiversity and the strong dependence of local communities on the reefs in the region. This study provides baseline data on coral disease frequencies within three national parks in Sabah, Borneo, which exhibit different levels of human impacts and management histories. High mean coral cover (55%) and variable disease frequency (mean 0.25 diseased colonies m(-2)) were found across the three sites. Highest disease frequency (0.44 diseased colonies per m(2)) was seen at the site closest to coastal population centres. Bleaching and pigmentation responses were actually higher at Sipadan, the more remote, offshore site, whereas none of the other coral diseases detected in the other two parks were detected in Sipadan. Results of this study offer a baseline dataset of disease in these parks and indicate the need for continued monitoring, and suggest that coral colonies in parks under higher anthropogenic stressors and with lower coral cover may be more susceptible to contracting disease.
  9. Yap BK, Buckle MJ, Doughty SW
    J Mol Model, 2012 Aug;18(8):3639-55.
    PMID: 22354276 DOI: 10.1007/s00894-012-1368-5
    5-HT(1A) serotonin and D1 dopamine receptor agonists have been postulated to be able to improve negative and cognitive impairment symptoms of schizophrenia, while partial agonists and antagonists of the D2 and 5-HT(2A) receptors have been reported to be effective in reducing positive symptoms. There is therefore a need for well-defined homology models for the design of more selective antipsychotic agents, since no three-dimensional (3D) crystal structures of these receptors are currently available. In this study, homology models were built based on the high-resolution crystal structure of the β(2)-adrenergic receptor (2RH1) and further refined via molecular dynamics simulations in a 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) lipid bilayer system with the GROMOS96 53A6 united atom force field. Docking evaluations with representative agonists and antagonists using AutoDock 4.2 revealed binding modes in agreement with experimentally determined site-directed mutagenesis data and significant correlations between the computed and experimental pK (i) values. The models are also able to distinguish between antipsychotic agents with different selectivities and binding affinities for the four receptors, as well as to differentiate active compounds from decoys. Hence, these human 5-HT(1A), 5-HT(2A), D1 and D2 receptor homology models are capable of predicting the activities of novel ligands, and can be used as 3D templates for antipsychotic drug design and discovery.
  10. Ismail A, Campbell MJ, Ibrahim HM, Jones GL
    PMID: 16813662
    Health Related Quality of Life (HRQoL) studies on children with chronic illness such as thalassaemia are limited. We conducted the first study to investigate if children with thalassaemia have a lower quality of life in the four dimensions as measured using the PedsQL 4.0 generic Scale Score: physical, emotional, social and role (school) functioning compared to the healthy controls allowing for age, gender, ethnicity and household income.
  11. Kumar S, Miranda-Massari JR, Gonzalez MJ, Riordan HD
    P R Health Sci J, 2004 Jun;23(2):125-6.
    PMID: 15377062
    We report a case of jellyfish envenomation in a 39 year old male. He was stung extensively on both lower limbs by an unidentified jellyfish. This occurred in shallow waters of a beach in the vicinity of Labuan Island, Malaysia. The patient received ambulatory treatment with parenteral and oral ascorbate with remarkable recovery.
  12. Granados A, Brodie JF, Bernard H, O'Brien MJ
    Ecol Appl, 2017 10;27(7):2092-2101.
    PMID: 28660670 DOI: 10.1002/eap.1592
    Vertebrate granivores destroy plant seeds, but whether animal-induced seed mortality alters plant recruitment varies with habitat context, seed traits, and among granivore species. An incomplete understanding of seed predation makes it difficult to predict how widespread extirpations of vertebrate granivores in tropical forests might affect tree communities, especially in the face of habitat disturbance. Many tropical forests are simultaneously affected by animal loss as well as habitat disturbance, but the consequences of each for forest regeneration are often studied separately or additively, and usually on a single plant demographic stage. The combined impacts of these threats could affect plant recruitment in ways that are not apparent when studied in isolation. We used wire cages to exclude large (elephants), medium, (sambar deer, bearded pigs, muntjac deer), and small (porcupines, chevrotains) ground-dwelling mammalian granivores and herbivores in logged and unlogged forests in Malaysian Borneo. We assessed the interaction between habitat disturbance (selective logging) and experimental defaunation on seed survival, germination, and seedling establishment in five dominant dipterocarp tree species spanning a 21-fold gradient in seed size. Granivore-induced seed mortality was consistently higher in logged forest. Germination of unpredated seeds was reduced in logged forest and in the absence of small to large-bodied mammals. Experimental defaunation increased germination and reduced seed removal but had little effect on seed survival. Seedling recruitment however, was more likely where logging and animal loss occurred together. The interacting effects of logging and hunting could therefore, actually increase seedling establishment, suggesting that the loss of mammals in disturbed forest could have important consequences for forest regeneration and composition.
  13. O'Brien MJ, Reynolds G, Ong R, Hector A
    Nat Ecol Evol, 2017 Nov;1(11):1643-1648.
    PMID: 28963453 DOI: 10.1038/s41559-017-0326-0
    Occasional periods of drought are typical of most tropical forests, but climate change is increasing drought frequency and intensity in many areas across the globe, threatening the structure and function of these ecosystems. The effects of intermittent drought on tropical tree communities remain poorly understood and the potential impacts of intensified drought under future climatic conditions are even less well known. The response of forests to altered precipitation will be determined by the tolerances of different species to reduced water availability and the interactions among plants that alleviate or exacerbate the effects of drought. Here, we report the response of experimental monocultures and mixtures of tropical trees to simulated drought, which reveals a fundamental shift in the nature of interactions among species. Weaker competition for water in diverse communities allowed seedlings to maintain growth under drought while more intense competition among conspecifics inhibited growth under the same conditions. These results show that reduced competition for water among species in mixtures mediates community resistance to drought. The delayed onset of competition for water among species in more diverse neighbourhoods during drought has potential implications for the coexistence of species in tropical forests and the resilience of these systems to climate change.
  14. Ross B, Penkunas MJ, Maher D, Certain E, Launois P
    BMJ Open, 2022 May 03;12(5):e054719.
    PMID: 35504633 DOI: 10.1136/bmjopen-2021-054719
    INTRODUCTION: An implementation research (IR) massive open online course (MOOC) was developed by the Special Programme for Research and Training in Tropical Diseases, to address the scarcity of training in low-income and middle-income countries in the field of IR. The Kirkpatrick model was used to evaluate the IR MOOC as it is widely applied for evaluation of training and educational programmes. The Kirkpatrick model evaluates training programmes on four levels: reaction, learning, behaviour and results. This paper addresses the impact of the IR MOOC on participants' professional practice.

    METHODS: Findings are based on analysis of survey and interview data collected 1.5-2 years after the conclusion of the two 2018 IR MOOC offerings. Of the 3858 MOC participants, 748 responded to the anonymous online survey and seven of these respondents were interviewed. All data are self-reported.

    RESULTS: The IR MOOC was successful in enhancing the professional practice of participants and for their organisations. Over 40% reported modifying or implementing changes in their professional work. Respondents reported that participation in the MOOC had improved their ability to conduct IR, enhanced their professional profiles and increased their opportunities for collaboration, research and job promotion. Respondents stated that the MOOC had improved their work quality and productivity, and allowed them to contribute to research, initiate and develop professional collaborations and train others in IR. Respondents reported an increase in applying for grants and scholarships and presenting and publishing work on IR after participating in the MOOC. Barriers applying the knowledge gained from the IR MOOC were experienced, for example, due to a lack of funding and lack of support from colleagues, managers and organisations.

    CONCLUSION: Participants perceived that the IR MOOC was successful in its aims of delivering medium-term and long-term results in relation to their own and their organisations' professional outcomes.

  15. Launois P, Maher D, Certain E, Ross B, Penkunas MJ
    Health Res Policy Syst, 2021 Apr 06;19(1):59.
    PMID: 33823859 DOI: 10.1186/s12961-021-00703-3
    BACKGROUND: Implementation research (IR) can play a critical role in the delivery of disease control interventions, particularly in low- and middle-income countries (LMICs). The growing demand for IR training has led to the development of a range of training programmes and university courses, the majority of which can not be accessed by learners in LMICs. This article reports on the evaluation of the massive open online course (MOOC) developed by the Special Programme for Research and Training in Tropical Diseases hosted by WHO on the topic of IR with a focus on infectious diseases of poverty. This study followed the Kirkpatrick Model to evaluate training programmes with a specific focus on post-training changes in behaviour.

    METHODS: MOOC participants were invited to take part in an anonymous online survey examining their knowledge of IR and how they applied it in their professional practice approximately 1-1.5 years after completing their course. The survey contained 43 open-ended, multiple choice and Likert-type questions. Descriptive statistics were calculated for the quantitative data and responses to the open-ended questions were thematically coded.

    RESULTS: A total of 748 MOOC participants responded to the survey. The demographic profile of the survey respondents aligned with that of the MOOC participants, with nearly 70% of respondents originating from Africa. Responses to the quantitative and open-ended survey questions revealed that respondents' knowledge of IR had improved to a large extent as a result of the MOOC, and that they used the knowledge and skills gained in their professional lives frequently and had consequently changed their professional behaviour. Respondents most often cited the problem-solving aspect of IR as a substantial area of behavioral change influenced by participating in the MOOC.

    CONCLUSIONS: These findings indicate that the MOOC was successful in targeting learners from LMICs, in strengthening their IR knowledge and contributing to their ability to apply it in their professional practice. The utility of MOOCs for providing IR training to learners in LMICs, where implementation challenges are encountered often, makes this platform an ideal standalone learning tool or one that could be combined with other training formats.

  16. bin Yusof MT, Kershaw MJ, Soanes DM, Talbot NJ
    PLoS One, 2014;9(6):e99760.
    PMID: 24949933 DOI: 10.1371/journal.pone.0099760
    The rice blast fungus Magnaporthe oryzae causes plant disease via specialised infection structures called appressoria. These dome-shaped cells are able to generate enormous internal pressure, which enables penetration of rice tissue by invasive hyphae. Previous studies have shown that mobilisation of lipid bodies and subsequent lipid metabolism are essential pre-requisites for successful appressorium-mediated plant infection, which requires autophagic recycling of the contents of germinated spores and germ tubes to the developing appressorium. Here, we set out to identify putative regulators of lipid metabolism in the rice blast fungus. We report the identification of FAR1 and FAR2, which encode highly conserved members of the Zn2-Cys6 family of transcriptional regulators. We generated Δfar1, Δfar2 and Δfar1Δfar2 double mutants in M. oryzae and show that these deletion mutants are deficient in growth on long chain fatty acids. In addition, Δfar2 mutants are also unable to grow on acetate and short chain fatty acids. FAR1 and FAR2 are necessary for differential expression of genes involved in fatty acid β-oxidation, acetyl-CoA translocation, peroxisomal biogenesis, and the glyoxylate cycle in response to the presence of lipids. Furthermore, FAR2 is necessary for expression of genes associated with acetyl-CoA synthesis. Interestingly, Δfar1, Δfar2 and Δfar1Δfar2 mutants show no observable delay or reduction in lipid body mobilisation during plant infection, suggesting that these transcriptional regulators control lipid substrate utilization by the fungus but not the mobilisation of intracellular lipid reserves during infection-related morphogenesis.
  17. Swaminathan M, Chee CF, Chin SP, Buckle MJ, Rahman NA, Doughty SW, et al.
    Molecules, 2014 Jun 27;19(7):8933-48.
    PMID: 24979399 DOI: 10.3390/molecules19078933
    Muscarinic acetylcholine receptor-active compounds have potential for the treatment of Alzheimer's disease. In this study, a series of natural and synthetic flavones and flavonols was assayed in vitro for their ability to inhibit radioligand binding at human cloned M1 muscarinic receptors. Several compounds were found to possess competitive binding affinity (Ki=40-110 µM), comparable to that of acetylcholine (Ki=59 µM). Despite the fact that these compounds lack a positively-charged ammonium group under physiological conditions, molecular modelling studies suggested that they bind to the orthosteric site of the receptor, mainly through non-polar interactions.
  18. Farah CS, Woo SB, Zain RB, Sklavounou A, McCullough MJ, Lingen M
    Int J Dent, 2014;2014:853479.
    PMID: 24891850 DOI: 10.1155/2014/853479
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