Displaying publications 1 - 20 of 76 in total

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  1. 1H NMR-Based Metabolic Profiles Delineate the Anticancer Effect of Vitamin C and Oxaliplatin on Hepatocellular Carcinoma Cells
    Lin C, Dong J, Wei Z, Cheng KK, Li J, You S, et al.
    J Proteome Res, 2020 02 07;19(2):781-793.
    PMID: 31916767 DOI: 10.1021/acs.jproteome.9b00635
    Hepatocellular carcinoma (HCC) is a leading cause of cancer death worldwide. Because of its high recurrence rate and heterogeneity, effective treatment for advanced stage of HCC is currently lacking. There are accumulating evidences showing the therapeutic potential of pharmacologic vitamin C (VC) on HCC. However, the metabolic basis underlying the anticancer property of VC remains to be elucidated. In this study, we used a high-resolution proton nuclear magnetic resonance-based metabolomics technique to assess the global metabolic changes in HCC cells following VC treatment. In addition, the HCC cells were also treated with oxaliplatin (OXA) to explore the potential synergistic effect induced by the combined VC and OXA treatment. The current metabolomics data suggested different mechanisms of OXA and VC in modulating cell growth and metabolism. In general, VC treatment led to inhibition of energy metabolism via NAD+ depletion and amino acid deprivation. On the other hand, OXA caused significant perturbation in phospholipid biosynthesis and phosphatidylcholine biosynthesis pathways. The current results highlighted glutathione metabolism, and pathways related to succinate and choline may play central roles in conferring the combined effect between OXA and VC. Taken together, this study provided metabolic evidence of VC and OXA in treating HCC and may contribute toward the potential application of combined VC and OXA as complementary HCC therapies.
  2. Fulltext 1H NMR-based Investigation of Metabolic Response to Electro-Acupuncture Stimulation
    Lin C, Wei Z, Cheng KK, Xu J, Shen G, She C, et al.
    Sci Rep, 2017 07 28;7(1):6820.
    PMID: 28754994 DOI: 10.1038/s41598-017-07306-5
    Acupuncture is a traditional Chinese medicine therapy that has been found useful for treating various diseases. The treatments involve the insertion of fine needles at acupoints along specific meridians (meridian specificity). This study aims to investigate the metabolic basis of meridian specificity using proton nuclear magnetic resonance (1H NMR)-based metabolomics. Electro-acupuncture (EA) stimulations were performed at acupoints of either Stomach Meridian of Foot-Yangming (SMFY) or Gallbladder Meridian of Foot-Shaoyang (GMFS) in healthy male Sprague Dawley (SD) rats. 1H-NMR spectra datasets of serum, urine, cortex, and stomach tissue extracts from the rats were analysed by multivariate statistical analysis to investigate metabolic perturbations due to EA treatments at different meridians. EA treatment on either the SMFY or GMFS acupoints induced significant variations in 31 metabolites, e.g., amino acids, organic acids, choline esters and glucose. Moreover, a few meridian-specific metabolic changes were found for EA stimulations on the SMFY or GMFS acupoints. Our study demonstrated significant metabolic differences in response to EA stimulations on acupoints of SMFY and GMFS meridians. These results validate the hypothesis that meridian specificity in acupuncture is detectable in the metabolome and demonstrate the feasibility and effectiveness of a metabolomics approach in understanding the mechanism of acupuncture.
  3. Assessing Microalgal Protein's Impact on Environment and Energy Footprint via Life Cycle Analysis
    Rawindran H, Lim JW, Lam MK, Supramaniam U, Tong WY, Ng HS, et al.
    Mol Biotechnol, 2023 Nov 14.
    PMID: 37964101 DOI: 10.1007/s12033-023-00955-0
    Conventionally, increasing the yield of microalgal biomass has been the primary focus of research, while the significant protein reserve within this biomass has remained largely unexplored. This protein reserve possesses substantial value and versatility, offering a wide range of prospective applications and presenting an enticing chance for innovation and value enhancement for various sectors. Current study employed an innovative research approach that focused solely on the LCA of protein production potential from microalgal biomass, a lesser-explored aspects within this domain. Most environmental impact categories were shown to be significantly affected by cultivation phase because of the electrical obligation, followed by the harvesting and protein extraction phase. Still, the environmental aspect was seen to yield a minimal impact on global warming potential, i.e., 4 × 10-3 kg CO2, underscoring the ecologically favorable nature of the process. Conversely, the overall energy impact was seen to intensify with NEB of - 39.33 MJ and NER of 0.49, drawing attention to the importance of addressing the energy aspect to harness the full potential of microalgal protein production.
  4. Biodegradation of high di-(2-Ethylhexyl) phthalate (DEHP) concentration by food waste composting and its toxicity assessment using seed germination test
    Tran HT, Lin C, Lam SS, Le TH, Hoang HG, Bui XT, et al.
    Environ Pollut, 2023 Jan 01;316(Pt 2):120640.
    PMID: 36403881 DOI: 10.1016/j.envpol.2022.120640
    Di-(2-ethylhexyl) phthalate (DEHP), a plasticizer derived from phthalate ester, is used as an additive in industrial products such as plastics, paints, and medical devices. However, DEHP is known as an endocrine-disrupting chemical, causing cancers and adverse effects on human health. This study evaluated DEHP biodegradation efficiency via food waste composting during 35 days of incubation. At high DEHP concentrations (2167 mg kg-1) in food waste compost mixture, the DEHP biodegradation efficiency was 99% after 35 days. The highest degradation efficiency was recorded at the thermophilic phase (day 3 - day 11) with the biodegradation rate reached 187 mg kg-1 day-1. DEHP was metabolized to dibutyl phthalate (DBP) and dimethyl phthalate (DMP) and would be oxidized to benzyl alcohol (BA) and mineralized into CO2 and water via various metabolisms. Finally, the compost's quality with residual DEHP was evaluated using Brassica chinensis L. seeds via 96 h of germination tests. The compost (at day 35) with a trace amount of DEHP as the end product showed no significant effect on the germination rate of Brassica chinensis L. seeds (88%) compared to that without DEHP (94%), indicating that the compost can be reused as fertilizer in agricultural applications. These results provide an improved understanding of the DEHP biodegradation via food waste composting without bioaugmentation and hence facilitating its green remediation and conversion into value-added products. Nevertheless, further studies are needed on DEHP biodegradation in large-scale food waste composting or industrial applications.
  5. Changing trends of prostate cancer in Asia
    Pu YS, Chiang HS, Lin CC, Huang CY, Huang KH, Chen J
    Aging Male, 2004 Jun;7(2):120-32.
    PMID: 15672937
    Although Asian people have the lowest incidence and mortality rates of prostate cancer in the world, these rates have risen rapidly in the past two decades in most Asian countries. Prostate cancer has become one of the leading male cancers in some Asian countries. In 2000, the age-adjusted incidence was over 10 per 100000 men in Japan, Taiwan, Singapore, Malaysia, the Philippines and Israel. Although some of the increases may result from enhanced detection, much of the increased incidence may be associated with westernization of the lifestyle, with increasing obesity and increased consumption of fat. The differences in incidences between native Americans and Asian immigrants are getting smaller, reflecting a possible improvement of diagnostic efforts and changes of environmental risk factors in Asian immigrants. Nevertheless, the huge variations in incidences among ethnic groups imply that there are important genetic risk factors. The stage distributions of prostate cancer in Asian populations are still unfavorable compared to those of Western developed countries. However, a trend towards diagnosing cancer with more favorable prognosis is seen in most Asian countries. Both genetic and environmental risk factors responsible for elevated risks in Asian people are being identified, which may help to reduce prostate cancer incidence in a chemopreventive setting.
  6. Fulltext Children's eating behaviour: A comparison between normal, overweight and obese children
    Kimin LS, Liew Sat Lin C, Avoi R, Hayati F, Mohd Daud MN, Mandrinos S, et al.
    Ann Med Surg (Lond), 2022 Dec;84:104890.
    PMID: 36536714 DOI: 10.1016/j.amsu.2022.104890
    BACKGROUND: Childhood obesity has become a major global health concern and has been increasing dramatically over the years. Previous study has shown that specific eating behaviours may have been associated with obesity especially under-responsiveness to internal satiety cues and over-responsiveness to external food cues such as the taste, smell, availability and emotions. However, there is still inadequate number of studies present to describe the association between the children's body mass index (BMI) and their eating behaviours, especially in Sabah, Malaysia. Therefore, the objective of this study is to established the association between the children's eating behaviours with their nutritional status based on their body mass index.

    MATERIALS AND METHODS: A cross-sectional study involving 484 children aged 6-12 years old was conducted in Kota Kinabalu, which is a developing urban area in Sabah. The children were recruited from five primary schools that were selected based on multistage stratified and convenience sampling method. Sociodemographic details and anthropometric measures both parents and children, and eating behaviours of children were assessed using Children Eating Behaviour Questionnaires (CEBQ). Age-adjusted BMI z-scores were then calculated according to the World Health Organization recommendations to assess nutritional status.

    RESULTS: The prevalence of childhood obesity among children aged 6-12 years old is 13.2%. The mean scores of 'Food Approach' subscales from the CEBQ showed higher mean score in overweight and obese groups as compared to the mean score in normal weight group. The mean scores of 'Food Avoidance' subscales showed lower mean score in overweight and obese groups as compared to mean score in normal weight group.

    CONCLUSION: This study provides evidence that childhood obesity is yet to be a prevalent health problem in a developing urban area considering the "Food approach" subscales were positively associated with the excess weight in children.

  7. Chitinasiproducens palmae gen. nov., sp. nov., a new member of the family Burkholderiaceae isolated from leaf tissues of oil palm (Elaeis guineensis Jacq.)
    Madhaiyan M, See-Too WS, Ee R, Saravanan VS, Wirth JS, Alex THH, et al.
    Int J Syst Evol Microbiol, 2020 Apr;70(4):2640-2647.
    PMID: 32202992 DOI: 10.1099/ijsem.0.004084
    A Gram-stain-negative, aerobic, rod-shaped, leaf-associated bacterium, designated JS23T, was isolated from surface-sterilized leaf tissue of an oil palm grown in Singapore and was investigated by polyphasic taxonomy. Phylogenetic analyses based on 16S rRNA gene sequences and 180 conserved genes in the genome of several members of Burkholderiaceae revealed that strain JS23T formed a distinct evolutionary lineage independent of other taxa within the family Burkholderiaceae. The predominant ubiquinone was Q-8. The primary polar lipids were phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, and an unidentified aminophospholipid. The major fatty acids were C16 : 0, summed feature 3 (C16 : 1 ω7c /C16 : 1 ω6c) and summed feature 8 (C18 : 1 ω7c /C18 : 1 ω6c). The size of the genome is 5.36 Mbp with a DNA G+C content of 66.2 mol%. Genomic relatedness measurements such as average nucleotide identity, genome-to-genome distance and digital DNA-DNA hybridization clearly distinguished strain JS23T from the closely related genera Burkholderia, Caballeronia, Mycetohabitans, Mycoavidus, Pandoraea, Paraburkholderia, Robbsia and Trinickia. Furthermore, average amino acid identity values and the percentages of conserved proteins, 56.0-68.4 and 28.2-45.5, respectively, were well below threshold values for genus delineation and supported the assignment of JS23T to a novel genus. On the basis of the phylogenetic, biochemical, chemotaxonomic and phylogenomic evidence, strain JS23T is proposed to represent a novel species of a new genus within the family Burkholderiaceae, for which the name Chitinasiproducens palmae gen. nov., sp. nov., is proposed with the type strain of JS23T (= DSM 27307T=KACC 17592T).
  8. Fulltext Complementary and alternative medicine (CAM) practices and dietary patterns in children with inflammatory bowel disease in Singapore and Malaysia
    Ong F, Seah Lee W, Lin C, Ng RT, Yee Wong S, Lim SL, et al.
    Pediatr Neonatol, 2018 10;59(5):494-500.
    PMID: 29352665 DOI: 10.1016/j.pedneo.2017.12.007
    BACKGROUND: The use of complementary and alternative medicine (CAM) has been associated with adverse effects and self-imposed dietary restrictions. The prevalence of its use in Asian children with inflammatory bowel disease (IBD) is unknown. We aimed to determine the prevalence, types, and factors associated with the use of CAM among children with IBD from Singapore and Malaysia, and to ascertain if dietary restriction was prevalent in patients who used CAM.
    METHODS: A cross-sectional study was conducted in which parents of children with IBD attending two tertiary pediatric IBD referral centres in Singapore and Malaysia were interviewed. Data about demographics, conventional treatment, complementary therapies and dietary patterns were collected in a questionnaire.
    RESULTS: Of 64 children with IBD interviewed, 83% (n = 53) reported the use of CAM (Singapore [90%] vs. Malaysia [76%]; p = 0.152). The median number of CAM agents used was two (range 1-10). The three most common types of CAM used were probiotics (64%), vitamin and mineral supplements (55%), and food-based therapies (36%). Among individual CAM categories, the use of food-based therapies was correlated significantly with nationality (r = 0.497, p 
  9. Constraints on parton distribution functions and extraction of the strong coupling constant from the inclusive jet cross section in pp collisions at [Formula: see text][Formula: see text]
    Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Bergauer T, Dragicevic M, et al.
    Eur Phys J C Part Fields, 2015 06 26;75(6):288.
    PMID: 26146483
    The inclusive jet cross section for proton-proton collisions at a centre-of-mass energy of 7[Formula: see text] was measured by the CMS Collaboration at the LHC with data corresponding to an integrated luminosity of 5.0[Formula: see text]. The measurement covers a phase space up to 2[Formula: see text] in jet transverse momentum and 2.5 in absolute jet rapidity. The statistical precision of these data leads to stringent constraints on the parton distribution functions of the proton. The data provide important input for the gluon density at high fractions of the proton momentum and for the strong coupling constant at large energy scales. Using predictions from perturbative quantum chromodynamics at next-to-leading order, complemented with electroweak corrections, the constraining power of these data is investigated and the strong coupling constant at the Z boson mass [Formula: see text] is determined to be [Formula: see text], which is in agreement with the world average.
  10. Constraints on the pMSSM, AMSB model and on other models from the search for long-lived charged particles in proton-proton collisions at [Formula: see text]
    Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Bergauer T, Dragicevic M, et al.
    Eur Phys J C Part Fields, 2015 07 17;75(7):325.
    PMID: 26213486
    Stringent limits are set on the long-lived lepton-like sector of the phenomenological minimal supersymmetric standard model (pMSSM) and the anomaly-mediated supersymmetry breaking (AMSB) model. The limits are derived from the results presented in a recent search for long-lived charged particles in proton-proton collisions, based on data collected by the CMS detector at a centre-of-mass energy of 8 TeV at the Large Hadron Collider. In the pMSSM parameter sub-space considered, 95.9 % of the points predicting charginos with a lifetime of at least 10 ns are excluded. These constraints on the pMSSM are the first obtained at the LHC. Charginos with a lifetime greater than 100 ns and masses up to about 800 GeV in the AMSB model are also excluded. The method described can also be used to set constraints on other models.
  11. Fulltext Deciphering the metabolic perturbation in hepatic alveolar echinococcosis: a 1H NMR-based metabolomics study
    Lin C, Chen Z, Zhang L, Wei Z, Cheng KK, Liu Y, et al.
    Parasit Vectors, 2019 Jun 13;12(1):300.
    PMID: 31196218 DOI: 10.1186/s13071-019-3554-0
    BACKGROUND: Hepatic alveolar echinococcosis (HAE) is caused by the growth of Echinococcus multilocularis larvae in the liver. It is a chronic and potentially lethal parasitic disease. Early stage diagnosis for this disease is currently not available due to its long asymptomatic incubation period. In this study, a proton nuclear magnetic resonance (1H NMR)-based metabolomics approach was applied in conjunction with multivariate statistical analysis to investigate the altered metabolic profiles in blood serum and urine samples obtained from HAE patients. The aim of the study was to identify the metabolic signatures associated with HAE.

    RESULTS: A total of 21 distinct metabolic differences between HAE patients and healthy individuals were identified, and they are associated with perturbations in amino acid metabolism, energy metabolism, glyoxylate and dicarboxylate metabolism. Furthermore, the present results showed that the Fischer ratio, which is the molar ratio of branched-chain amino acids to aromatic amino acids, was significantly lower (P 

  12. Distributions of topological observables in inclusive three- and four-jet events in pp collisions at [Formula: see text][Formula: see text]
    Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Bergauer T, Dragicevic M, et al.
    Eur Phys J C Part Fields, 2015 07 01;75(7):302.
    PMID: 26190937
    This paper presents distributions of topological observables in inclusive three- and four-jet events produced in pp collisions at a centre-of-mass energy of 7[Formula: see text] with a data sample collected by the CMS experiment corresponding to a luminosity of 5.1[Formula: see text]. The distributions are corrected for detector effects, and compared with several event generators based on two- and multi-parton matrix elements at leading order. Among the considered calculations, MadGraph interfaced with pythia6 displays the overall best agreement with data.
  13. Epicardial Adipose Tissue Assessed by Computed Tomography and Echocardiography Are Associated With Adverse Cardiovascular Outcomes: A Systematic Review and Meta-Analysis
    Chong B, Jayabaskaran J, Ruban J, Goh R, Chin YH, Kong G, et al.
    Circ Cardiovasc Imaging, 2023 May;16(5):e015159.
    PMID: 37192298 DOI: 10.1161/CIRCIMAGING.122.015159
    BACKGROUND: Epicardial adipose tissue (EAT) has garnered attention as a prognostic and risk stratification factor for cardiovascular disease. This study, via meta-analyses, evaluates the associations between EAT and cardiovascular outcomes stratified across imaging modalities, ethnic groups, and study protocols.

    METHODS: Medline and Embase databases were searched without date restriction on May 2022 for articles that examined EAT and cardiovascular outcomes. The inclusion criteria were (1) studies measuring EAT of adult patients at baseline and (2) reporting follow-up data on study outcomes of interest. The primary study outcome was major adverse cardiovascular events. Secondary study outcomes included cardiac death, myocardial infarction, coronary revascularization, and atrial fibrillation.

    RESULTS: Twenty-nine articles published between 2012 and 2022, comprising 19 709 patients, were included in our analysis. Increased EAT thickness and volume were associated with higher risks of cardiac death (odds ratio, 2.53 [95% CI, 1.17-5.44]; P=0.020; n=4), myocardial infarction (odds ratio, 2.63 [95% CI, 1.39-4.96]; P=0.003; n=5), coronary revascularization (odds ratio, 2.99 [95% CI, 1.64-5.44]; P<0.001; n=5), and atrial fibrillation (adjusted odds ratio, 4.04 [95% CI, 3.06-5.32]; P<0.001; n=3). For 1 unit increment in the continuous measure of EAT, computed tomography volumetric quantification (adjusted hazard ratio, 1.74 [95% CI, 1.42-2.13]; P<0.001) and echocardiographic thickness quantification (adjusted hazard ratio, 1.20 [95% CI, 1.09-1.32]; P<0.001) conferred an increased risk of major adverse cardiovascular events.

    CONCLUSIONS: The utility of EAT as an imaging biomarker for predicting and prognosticating cardiovascular disease is promising, with increased EAT thickness and volume being identified as independent predictors of major adverse cardiovascular events.

    REGISTRATION: URL: https://www.crd.york.ac.uk/prospero; Unique identifier: CRD42022338075.

  14. Evaluation of the Seventh Malaysian Health Plan: a new approach
    Yon RB, Hamidy MA, Lin CY
    Asia Pac J Public Health, 2001;13(1):54-8.
    PMID: 12109263
    Since the First Malaysia Plan (1966-1970) many reviews have been done on the five-year health plans of the Ministry of Health (MOH). These included the Mid-Term Reviews and the review done at the end of the respective five-year plan period. There was no structured evaluation method carried out until the Seventh Malaysia Plan (7MP) period (1996-2000), among others because of the complexity of the MOH health plans. The evaluation of the 7MP was the first one conducted using a better-structured process. The findings and recommendations of the evaluation were used and incorporated in the subsequent 5-year health plan, under the Eighth Malaysia Plan (2001-2005).
  15. Event generator tunes obtained from underlying event and multiparton scattering measurements
    Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, et al.
    Eur Phys J C Part Fields, 2016 03 17;76:155.
    PMID: 27471433
    New sets of parameters ("tunes") for the underlying-event (UE) modelling of the pythia8, pythia6 and herwig++ Monte Carlo event generators are constructed using different parton distribution functions. Combined fits to CMS UE proton-proton ([Formula: see text]) data at [Formula: see text] and to UE proton-antiproton ([Formula: see text]) data from the CDF experiment at lower [Formula: see text], are used to study the UE models and constrain their parameters, providing thereby improved predictions for proton-proton collisions at 13[Formula: see text]. In addition, it is investigated whether the values of the parameters obtained from fits to UE observables are consistent with the values determined from fitting observables sensitive to double-parton scattering processes. Finally, comparisons are presented of the UE tunes to "minimum bias" (MB) events, multijet, and Drell-Yan ([Formula: see text] lepton-antilepton+jets) observables at 7 and 8[Formula: see text], as well as predictions for MB and UE observables at 13[Formula: see text].
  16. First Report of Fruit Rot of Loquat Caused by an Alternaria sp. in Taiwan
    Ko Y, Liu CW, Chen SS, Chen CY, Yao KS, Maruthasalam S, et al.
    Plant Dis, 2010 Apr;94(4):481.
    PMID: 30754488 DOI: 10.1094/PDIS-94-4-0481B
    During March 2007, a fruit rot disease was observed in several loquat (Eriobotrya japonica (Thunberg) Lindley) fields located in Taichung, Nantou, and Miaoli counties. Loquat is a valuable fruit crop grown predominantly in central Taiwan, and hence, even a minor yield loss by this new disease is economically significant. Symptoms on fruits initially appeared as small lesions (<1 mm) that later developed into light-to-dark brown, circular, larger (7 mm), sunken lesions, indicating invasion of a pathogen into the fruit. Pieces of rotted fruit tissue (1 × 1 × 1 mm) were immersed for 1 min in 3% commercial bleach, followed by 70% ethanol, cultured on potato dextrose agar (PDA), and incubated under constant fluorescent light (185 ± 35 μE·m-2·s-1) at 24°C for 2 days. Three single conidial isolates (AS1 to AS3) were selected and used in morphological and pathogenicity studies. All three isolates were identified as an Alternaria sp. (1-3) and formed abundant, dark brown mycelium when cultured on PDA with light at 24°C. Conidiophores were 60 to 89 × 3 to 5 μm, densely fasciculate, cylindrical, simple or branched, and had distinct conidial scars. Conidia were 12 to 74 × 6 to 14 μm, golden brown, straight or curved, obclavate with beaks measuring half the length of the conidium, and observed in chains of 10 or more spores with four to seven transverse septa and several longitudinal septa. Pathogenicity tests were conducted twice by inoculating eight surface-sterilized wounded or unwounded fruits with each of the three isolates in each experiment. Two cuts (1 × 1 × 1 mm) were made on each fruit 3 cm apart with a sterile scalpel, and a 300-μl spore suspension (2 × 105 conidia per ml) was placed on each wound. Similarly, a 300-μl spore suspension was placed on unwounded fruits and air dried for 5 min. Control fruits were similarly treated with sterile water. Inoculated fruits were enclosed in a plastic bag and kept at 24 ± 1°C. Symptoms of soft rot were observed on 60% (unwounded) and 100% (wounded) of inoculated fruits 5 days after inoculation, while control fruits did not develop disease symptoms. Reisolation from the symptomatic fruits consistently yielded an Alternaria sp. This fungus previously has been reported as the causal agent of fruit rot or black spot of papaya, mango, kiwifruit, pear, and carambola from Australia, India, Malaysia, South Africa, and the United States (1-3). To our knowledge, this is the first report of fruit rot of loquat caused by an Alternaria sp. in Taiwan. To manage this disease, growers may resort to fungicidal sprays followed by bagging of fruits to reduce pre- and postharvest losses. References: (1) A. L. Jones and H. S. Aldwinckle. Compendium of Apple and Pear Diseases. The American Phytopathological Society. St. Paul, MN, 1990. (2) R. C. Ploetz. Diseases of Tropical Fruit Crops. CABI Publishing. Wallingford, Oxfordshire, UK, 2003. (3) R. C. Ploetz et al. Compendium of Tropical Fruit Diseases. The American Phytopathological Society. St. Paul, MN, 1994.
  17. First Report of Fruit Rot of Strawberry Caused by an Alternaria sp. in Taiwan
    Ko Y, Chen CY, Yao KS, Liu CW, Maruthasalam S, Lin CH
    Plant Dis, 2008 Aug;92(8):1248.
    PMID: 30769472 DOI: 10.1094/PDIS-92-8-1248B
    In March 2005, a fruit rot disease was found in several commercial strawberry (Fragaria × ananassa Duchesne) fields at Fongyuan, 24.25°N, 120.72°E, in Taichung County in central Taiwan. The disease was rare and was negligible in most cultivated areas. However, disease incidence has increased by 4 to 5% over the last 2 years and causes significant postharvest losses. In storage, symptoms on berries include light brown-to-black, sunken, irregularly shaped lesions. The lesions gradually enlarge and become firm with a dark green-to-black, velvety surface composed of mycelia, conidiophores, and conidia. Twelve single conidial isolates (AF-1 to AF-12) of a fungus were isolated by placing portions of symptomatic fruit from four locations onto acidified potato dextrose agar (PDA) and incubating at 24 ± 1°C. One isolate from each of the four locations, AF-2, 6, 9, and 12, was selected for identification and pathogenicity studies. The fungus was identified as an Alternaria sp. according to the morphological descriptions of A. tenuissima (2,3). Conidiophores were simple or branched, straight or flexuous, septate, pale to light brown, 3.0 to 5.0 μm in diameter, and bore two to six conidia in a chain. Conidia were dark brown, obclavate or oval, and multicellular with seven transverse (in most cases) and numerous longitudinal septa. Conidia were 15.5 to 56.5 μm (average 35.0 μm) long × 6.0 to 15.0 μm (average 11.0 μm) wide at the broadest point. The pathogen was consistently isolated from berries in the field or in storage. Pathogenicity tests were conducted by inoculating 12 surface-sterilized berries with each of the four isolates. Approximately 300 μl of a spore suspension (2 × 105 conidia per ml) was placed at two points on the uninjured surface of each fruit and allowed to dry for 5 min. Control fruits were treated with sterile water. The berries were then enclosed in a plastic bag and incubated at 24 ± 1°C for 2 days. Disease symptoms similar to those described above were observed on 95% of inoculated berries 3 days after inoculation, while no symptoms developed in control berries. Reisolation from the inoculated berries consistently yielded the Alternaria sp. described above. Pathogenicity tests were performed three times. Previously, strawberry fruit rot caused by A. tenuissima was reported from Florida (2) and Malaysia (1), however, to our knowledge, this is the first report of fruit rot of strawberry caused by a species of Alternaria in Taiwan. References: (1) W. D. Cho et al. List of Plant Diseases in Korea. Korean Society of Plant Pathology, 2004. (2) C. M. Howard and E. E. Albregts. Phytopathology 63:938, 1973. (3) R. D. Milholland. Phytopathology 63:1395, 1973.
  18. First Report of Gray Leaf Spot of Mango (Mangifera indica) Caused by Pestalotiopsis mangiferae in Taiwan
    Ko Y, Yao KS, Chen CY, Lin CH
    Plant Dis, 2007 Dec;91(12):1684.
    PMID: 30780618 DOI: 10.1094/PDIS-91-12-1684B
    Mango (Mangifera indica L.; family Anacardiaceae) is one of the world's most important fruit crops and is widely grown in tropical and subtropical regions. Since 2001, a leaf spot disease was found in mango orchards of Taiwan. Now, the disease was observed throughout (approximately 21,000 ha) Taiwan in moderate to severe form, thus affecting the general health of mango trees and orchards. Initial symptoms were small, yellow-to-brown spots on leaves. Later, the irregularly shaped spots, ranging from a few millimeters to a few centimeters in diameter, turned white to gray and coalesced to form larger gray patches. Lesions had slightly raised dark margins. On mature lesions, numerous black acervuli, measuring 290 to 328 μm in diameter, developed on the gray necrotic areas. Single conidial isolates of the fungus were identified morphologically as Pestalotiopsis mangiferae (Henn.) Steyaert (2,3) and were consistently isolated from the diseased mango leaves on acidified (0.06% lactic acid) potato dextrose agar (PDA) medium incubated at 25 ± 1°C. Initially, the fungus grew (3 mm per day) on PDA as a white, chalky colony that subsequently turned gray after 2 weeks. Acervuli developed in culture after continuous exposure to light for 9 to 12 days at 20 to 30°C. Abundant conidia oozed from the acervulus as a creamy mass. The conidia (17.6 to 25.4 μm long and 4.8 to 7.1 μm wide) were fusiform and usually straight to slightly curved with four septa. Three median cells were olivaceous and larger than the hyaline apical and basal cells. The apical cells bore three (rarely four) cylindrical appendages. Pathogenicity tests were conducted with either 3-day-old mycelial discs or conidial suspension (105 conidia per ml) obtained from 8- to 10-day-old cultures. Four leaves on each of 10 trees were inoculated. Before inoculation, the leaves were washed with a mild detergent, rinsed with tap water, and then surface sterilized with 70% ethanol. Leaves were wounded with a needle and exposed to either a 5-mm mycelial disc or 0.2 ml of the spore suspension. The inoculated areas were wrapped with cotton pads saturated with sterile water and the leaves were covered with polyethylene bags for 3 days to maintain high relative humidity. Wounded leaves inoculated with PDA discs alone served as controls. The symptoms described above were observed on all inoculated leaves, whereas uninoculated leaves remained completely free from symptoms. Reisolation from the inoculated leaves consistently yielded P. mangiferae, thus fulfilling Koch's postulates. Gray leaf spot is a common disease of mangos in the tropics and is widely distributed in Africa and Asia (1-3); however, to our knowledge, this is the first report of gray leaf spot disease affecting mango in Taiwan. References: (1) T. K. Lim and K. C. Khoo. Diseases and Disorders of Mango in Malaysia. Tropical Press. Malaysia, 1985. (2) J. E. M. Mordue. No. 676 in: CMI Descriptions of Pathogenic Fungi and Bacteria. Surrey, England, 1980. (3) R. C. Ploetz et al. Compendium of Tropical Fruit Diseases. The American Phytopathological Society. St. Paul, MN, 1994.
  19. First Report of Rubber Tree Stem Rot Caused by Fusarium oxysporum in China
    Li BX, Shi T, Liu XB, Lin CH, Huang GX
    Plant Dis, 2014 Jul;98(7):1008.
    PMID: 30708897 DOI: 10.1094/PDIS-01-14-0004-PDN
    Rubber tree (Hevea brasiliensis) is an important crop in tropical regions of China. In October 2013, a new stem rot disease was found on cv. Yunyan77-4 at a rubber tree plantation in Hekou, Yunnan Province. There were about 100 plants, and diseased rubber trees accounted for 30% or less. Initially, brown-punctuate secretion appeared on the stem, which was 5 to 6 cm above the ground. Eventually, the secretion became black and no latex produced from the rubber tree bark. After removing the secretion, the diseased bark was brown putrescence, but the circumambient bark was normal. Upon peeling the surface bark, the inner bark and xylem had brown rot and was musty. The junction between health and disease was undulate. On the two most serious plants, parts of leaves on the crown were yellow, and the root near the diseased stem was dry and puce. The pathogen was isolated and designated HbFO01; the pathogenicity was established by following Koch's postulates. The pathogen was cultivated on a potato dextrose agar (PDA) plate at 28°C for 4 days. Ten plants of rubber tree cv. Yunyan77-4 were selected from a disease-free plantation in Haikou, Hainan Province, and the stem diameter was about 7 cm. The bark of five plants was peeled, and one mycelium disk with a diameter of 1 cm was inserted into the cut and covered again with the bark. The other five plants were treated with agar disks as controls. The inoculation site was kept moist for 2 days, and then the mycelium and agar disk were removed. On eighth day, symptoms similar to the original stem lesions were observed on stems of inoculated plants, while only scars formed on stems of control plants. The pathogen was re-isolated from the lesions of inoculated plants. On PDA plates, the pathogen colony was circular and white with tidy edges and rich aerial hyphae. Microscopic examination showed microconidia and chlamydospores were produced abundantly on PDA medium. The falciform macroconidia were only produced on lesions and were slightly curved, with a curved apical cell and foot shaped to pointed basal cell, usually 3-septate, 16.2 to 24.2 × 3.2 to 4.0 μm. Microconidia were produced in false heads, oval, 0-septate, 6.2 to 8.2 × 3.3 to 3.8 μm, and the phialide was cylindrical. Chlamydospores were oval, 6.4 to 7.2 × 3.1 to 3.8 μm, alone produced in hypha. Morphological characteristics of the specimen were similar to the descriptions for Fusarium oxysporum (2). Genomic DNA of this isolate was extracted with a CTAB protocol (4) from mycelium and used as a template for amplification of the internal transcribed spacer (ITS) region of rDNA with primer pair ITS1/ITS4 (1). The full length of this sequence is 503 nt (GenBank Accession No. KJ009335), which exactly matched several sequences (e.g., JF807394.1, JX897002.1, and HQ451888.1) of F. oxysporum. Williams and Liu had listed F. oxysporum as the economically important pathogen of Hevea in Asia (3), while this is, to our knowledge, the first report of stem rot caused by F. oxysporum on rubber tree in China. References: (1) D. E. L. Cooke et al. Fungal Genet. Biol. 30:17, 2000. (2) J. F. Leslie and B. A. Summerell. The Fusarium Laboratory Manual, 2006. (3) T. H. Williams and P. S. W. Liu. A host list of plant diseases in Sabah, Malaysia, 1976. (4) J. R. Xu et al. Genetics 143:175, 1996.
  20. First Report of Stem-End Rot of Mango Caused by Phomopsis mangiferae in Taiwan
    Ko Y, Liu CW, Chen CY, Maruthasalam S, Lin CH
    Plant Dis, 2009 Jul;93(7):764.
    PMID: 30764368 DOI: 10.1094/PDIS-93-7-0764A
    Mango (Mangifera indica L.) is grown on approximately 20,000 ha in Taiwan. It is an economically important crop and the income of many fruit farmers comes primarily from mango production. During 2006 and 2007, a stem-end rot disease was observed 1 week after harvest on 28 to 36% of stored mangoes picked from six orchards in the Pingtung, Tainan, and Kaoshiung regions. Two popular mango cultivars, Keitt and Irwin, showed greater susceptibility to this disease, while 'Haden' was found to be moderately susceptible. In storage, symptoms initially appeared as light-to-dark brown lesions surrounding peduncles. Rot symptoms advanced slowly but eventually penetrated the mesocarp, which consequently reduced the commercial value of fruits. The fungus formed abundant pycnidia (0.1 to 0.6 mm in diameter) on infected fruits in advanced stages of symptom development. Pieces of symptomatic fruits plated on acidified potato dextrose agar (PDA) and incubated at 25 ± 1°C consistently yielded the same fungus. A single conidial isolate was cultured. Pycnidia developed on PDA after continuous exposure to light for 9 to 14 days. On the basis of morphological characteristics, the fungus was identified as Phomopsis mangiferae L. (2,3). Pycnidia released two types of conidia: α-conidia (5 to 10 × 2.3 to 4.0 μm) were hyaline and oval to fusoid; and β-conidia (15.0 to 37.5 × 1.3 to 2.5 μm) were hyaline and filiform with characteristic curves. Conidiophores were hyaline, filiform, simple or branched, septate, and 15 to 75 μm long. Cultures incubated under continuous fluorescent light (185 ± 35 μE·m-2·s-1) at 25°C for 3 days were used as inoculum for pathogenicity tests. Five fruits from 'Keitt' were wounded with a sterilized scalpel and each wound (2 × 2 × 2 mm) was inoculated with either a 5-mm mycelium agar plug or a 0.5-ml spore suspension (105 conidia per ml) of the fungus. Five wounded fruits inoculated with 5-mm PDA plugs or sterile water alone served as controls. Inoculated areas were covered with moist, sterile cotton. Fruits were enclosed in plastic bags and incubated at 24°C for 3 days. The test was performed three times. The same symptoms were observed on all inoculated fruits, whereas no decay was observed on control fruits. Reisolations from the inoculated fruits consistently yielded P. mangiferae, thus fulfilling Koch's postulates. This disease has previously been reported in Australia, Brazil, China, Cuba, India, Malaysia, and the United States (1). To our knowledge, this is the first report of P. mangiferae causing stem-end rot disease on mangoes in Taiwan. Our report necessitates taking preventive strategies in the field, prior to or after harvest, to contain postharvest losses in mangoes. References: (1) G. I. Johnson. Page 39 in: Compendium of Tropical Fruit Diseases. R. C. Ploetz et al., eds. The American Phytopathological Society. St. Paul, MN, 1994. (2) R. C. Ploetz, ed. Page 354 in: Diseases of Tropical Fruit Crops. CABI Publishing. Wallingford, UK, 2003. (3) E. Punithalingam. No. 1168 in: Descriptions of Pathogenic Fungi and Bacteria. CMI, Kew, Surrey, UK, 1993.
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