Publications by authors named "Li-Juan Mao"

17 Publications

  • Page 1 of 1

A child with household transmitted COVID-19.

BMC Infect Dis 2020 May 7;20(1):329. Epub 2020 May 7.

Department of Pediatrics, The Fourth Affiliated Hospital of Zhejiang University School of Medicine, N1 Shangcheng Avenue, Yiwu, 322000, Zhejiang Province, China.

Background: Although people of all ages are susceptible to the novel coronavirus infection, which is presently named "Coronavirus Disease 2019" (COVID-19), there has been relatively few cases reported among children. Therefore, it is necessary to understand the clinical characteristics of COVID-19 in children and the differences from adults.

Case Presentation: We report one pediatric case of COVID-19. A 14-month-old boy was admitted to the hospital with a symptom of fever, and was diagnosed with a mild form of COVID-19. The child's mother and grandmother also tested positive for SARS-CoV-2 RNA. However, the lymphocyte counts were normal. The chest computed tomography (CT) revealed scattered ground glass opacities in the right lower lobe close to the pleura and resorption after the treatment. The patient continued to test positive for SARS-CoV-2 RNA in the nasopharyngeal swabs and stool at 17 days after the disappearance of symptoms.

Conclusion: The present pediatric case of COVID-19 was acquired through household transmission, and the symptoms were mild. Lymphocyte counts did not significantly decrease. The RNA of SARS-CoV-2 in stool and nasopharyngeal swabs remained positive for an extended period of time after the disappearance of symptoms. This suggests that attention should be given to the potential contagiousness of pediatric COVID-19 cases after clinical recovery.
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http://dx.doi.org/10.1186/s12879-020-05056-wDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7205374PMC
May 2020

Metabolomics Analysis Identifies Sphingolipids as Key Signaling Moieties in Appressorium Morphogenesis and Function in Magnaporthe oryzae.

mBio 2019 08 20;10(4). Epub 2019 Aug 20.

State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, China

The blast fungus initiates infection using a heavily melanized, dome-shaped infection structure known as the appressorium, which forcibly ruptures the cuticle to enter the rice leaf tissue. How this process takes place remains not fully understood. Here, we used untargeted metabolomics analyses to profile the metabolome of developing appressoria and identified significant changes in six key metabolic pathways, including early sphingolipid biosynthesis. Analyses employing small molecule inhibitors, gene disruption, or genetic and chemical complementation demonstrated that ceramide compounds of the sphingolipid biosynthesis pathway are essential for normal appressorial development controlled by mitosis. In addition, ceramide was found to act upstream from the protein kinase C-mediated cell wall integrity pathway during appressorium repolarization and pathogenicity in rice blast. Further discovery of the sphingolipid biosynthesis pathway revealed that glucosylceramide (GlcCer) synthesized by ceramide is the key substance affecting the pathogenicity of Our results provide new insights into the chemical moieties involved in the infection-related signaling networks, thereby revealing a potential target for the development of novel control agents against the major disease of rice and other cereals. Our untargeted analysis of metabolomics throughout the course of pathogenic development gave us an unprecedented high-resolution view of major shifts in metabolism that occur in the topmost fungal pathogen that infects rice, wheat, barley, and millet. Guided by these metabolic insights, we demonstrated their practical application by using two different small-molecule inhibitors of sphingolipid biosynthesis enzymes to successfully block the pathogenicity of Our study thus defines the sphingolipid biosynthesis pathway as a key step and potential target that can be exploited for the development of antifungal agents. Furthermore, future investigations that exploit such important metabolic intermediates will further deepen our basic understanding of the molecular mechanisms underlying the establishment of fungal blast disease in important cereal crops.
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http://dx.doi.org/10.1128/mBio.01467-19DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6703424PMC
August 2019

Identification and characterization of new Muscodor endophytes from gramineous plants in Xishuangbanna, China.

Microbiologyopen 2019 04 21;8(4):e00666. Epub 2018 Jun 21.

State Key Laboratory for Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, China.

The endophytic fungi Muscodor spp. produce volatile organic compounds (VOCs) which can inhibit and even kill pathogenic fungi, bacteria, and nematodes. Nine endophytic fungal strains, isolated from the shoots of gramineous plants including Arthraxon hispidus, Eleusine indica, Oplismenus undulatifolius, and Oryza granulata, were identified as Muscodor through phylogenetic analysis of the internal transcribed spacer. Through an SPSS K-means cluster analysis, the nine Muscodor strains were divided into four groups based on the antifungal activities of the VOCs produced by these fungi determined by a two-section confrontation test. The first group contains the strains Y-L-54, W-S-41, Y-S-35, W-T-27, and Y-L-56, which showed the strongest activity. The second and third groups contain W-S-35 and Y-L-43, which showed stronger and moderate activity, respectively. The fourth group contains W-S-38 and N-L-7, which were the weakest in inhibiting the tested pathogens. Thirty-five compounds and the relative amounts of VOCs were determined by SPME-GC-MS and comparison with the NIST14 mass spectrometry database and Agilent MassHunter qualitative and quantitative analyses. These 35 compounds were classified into two different categories: (a) the product of fatty acid degradation, and (b) the intermediate and final metabolite of the metabolic pathway with the precursor of mevalonic acid. SPSS clustering analysis showed that the chemical components of VOCs might be correlated with their bioactivity rather than their phylogenetic assignment and some of the identified compounds might be responsible for antifungal activity. In conclusion, new Muscodor endophytes were recorded in tropical gramineous plants and a number of strains showed remarkable bioactive properties. Therefore, they have important potential applications in the fields of plant disease control.
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http://dx.doi.org/10.1002/mbo3.666DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6460276PMC
April 2019

An autophagy gene, HoATG5, is involved in sporulation, cell wall integrity and infection of wounded barley leaves.

Microbiol Res 2016 Nov 12;192:326-335. Epub 2016 Aug 12.

State Key Laboratory for Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, 310058, China. Electronic address:

The endophytic fungus Harpophora oryzae is a beneficial endosymbiont isolated from wild rice. H. oryzae can not only promote rice growth and biomass accumulation but also protect rice roots from invasion by its close relative Magnaporthe oryzae. Autophagy is a highly evolutionary conserved process from lower to higher eukaryotic organisms, and is involved in the maintenance of normal cell differentiation and development. In this study, we isolated a gene (HoATG5) which encodes an essential protein required for autophagy from the beneficial endophyte fungus H. oryzae. Using targeted gene replacement, a ΔHoATG5 mutant was generated and used to investigate the biological functions of autophagy in H. oryzae. We found that the autophagic process was blocked in the HoATG5 deletion mutant. The mutant showed increased vegetative growth and sporulation, and was sensitive to nutrient starvation. The ΔHoATG5 mutant lost its ability to penetrate and infect the wounded barley leaves. These results provide new knowledge to elaborate the molecular machinery of autophagy in endophytic fungi.
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http://dx.doi.org/10.1016/j.micres.2016.08.008DOI Listing
November 2016

Trichoderma Biodiversity of Agricultural Fields in East China Reveals a Gradient Distribution of Species.

PLoS One 2016 2;11(8):e0160613. Epub 2016 Aug 2.

State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, Zhejiang, China.

We surveyed the Trichoderma (Hypocreales, Ascomycota) biodiversity in agricultural fields in four major agricultural provinces of East China. Trichoderma strains were identified based on molecular approaches and morphological characteristics. In three sampled seasons (spring, summer and autumn), 2078 strains were isolated and identified to 17 known species: T. harzianum (429 isolates), T. asperellum (425), T. hamatum (397), T. virens (340), T. koningiopsis (248), T. brevicompactum (73), T. atroviride (73), T. fertile (26), T. longibrachiatum (22), T. pleuroticola (16), T. erinaceum (16), T. oblongisporum (2), T. polysporum (2), T. spirale (2), T. capillare (2), T. velutinum (2), and T. saturnisporum (1). T. harzianum, T. asperellum, T. hamatum, and T. virens were identified as the dominant species with dominance (Y) values of 0.057, 0.052, 0.048, and 0.039, respectively. The species amount, isolate numbers and the dominant species of Trichoderma varied between provinces. Zhejiang Province has shown the highest diversity, which was reflected in the highest species amount (14) and the highest Shannon-Wiener diversity index of Trichoderma haplotypes (1.46). We observed that relative frequencies of T. hamatum and T. koningiopsis under rice soil were higher than those under wheat and maize soil, indicating the preference of Trichoderma to different crops. Remarkable seasonal variation was shown, with summer exhibiting the highest biodiversity of the studied seasons. These results show that Trichoderma biodiversity in agricultural fields varies by region, crop, and season. Zhejiang Province (the southernmost province in the investigated area) had more T. hamatum than Shandong Province (the northernmost province), not only in isolate amounts but also in haplotype amounts. Furthermore, at haplotype level, only T. hamatum showed a gradient distribution from south to north in correspondence analysis among the four dominant species. The above results would contribute to the application of Trichoderma biocontrol strains.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0160613PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4970770PMC
July 2017

Intracoronary Transplantation of Mesenchymal Stem Cells with Overexpressed Integrin-Linked Kinase Improves Cardiac Function in Porcine Myocardial Infarction.

Sci Rep 2016 Jan 11;6:19155. Epub 2016 Jan 11.

Department of Cardiology, Affiliated Drum Tower Hospital, Nanjing University School of Medicine, Nanjing, China.

The effect of mesenchymal stem cell (MSCs)-based therapy on treating acute myocardial infarction (MI) is limited due to poor engraftment and limited regenerative potential. Here we engineered MSCs with integrin-linked kinase (ILK), a pleiotropic protein critically regulating cell survival, proliferation, differentiation, and angiogenesis. We firstly combined ferumoxytol with poly-L-lysine (PLL), and found this combination promisingly enabled MRI visualization of MSCs in vitro and in vivo with good safety. We provided visually direct evidence that intracoronary ILK-MSCs had substantially enhanced homing capacity to infarct myocardium in porcine following cardiac catheterization induced MI. Intracoronary transplantation of allogeneic ILK-MSCs, but not vector-MSCs, significantly enhanced global left ventricular ejection fraction (LVEF) by 7.8% compared with baseline, by 10.3% compared with vehicles, and inhibited myocardial remodeling compared with vehicles at 15-day follow-up. Compared with vector-MSCs, ILK-MSCs significantly improved regional LV contractile function, reduced scar size, fibrosis, cell apoptosis, and increased regional myocardial perfusion and cell proliferation. This preclinical study indicates that ILK-engineered MSCs might promote the clinical translation of MSC-based therapy in post-MI patients, and provides evidence that ferumoxytol labeling of cells combined with PLL is feasible in in vivo cell tracking.
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http://dx.doi.org/10.1038/srep19155DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4707493PMC
January 2016

Agrobacterium tumefaciens-mediated transformation: An efficient tool for insertional mutagenesis and targeted gene disruption in Harpophora oryzae.

Microbiol Res 2016 Jan 9;182:40-8. Epub 2015 Oct 9.

State Key Laboratory for Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, China; China Tobacco Gene Research Center, Zhengzhou Tobacco Institute of CNTC, Zhengzhou, China. Electronic address:

The endophytic filamentous fungus Harpophora oryzae is a beneficial endosymbiont isolated from the wild rice. H. oryzae could not only effectively improve growth rate and biomass yield of rice crops, but also induce systemic resistance against the rice blast fungus, Magnaporthe oryzae. In this study, Agrobacterium tumefaciens-mediated transformation (ATMT) was employed and optimized to modify the H. oryzae genes by either random DNA fragment integration or targeted gene replacement. Our results showed that co-cultivation of H. oryzae conidia with A. tumefaciens in the presence of acetosyringone for 48 h at 22 °C could lead to a relatively highest frequency of transformation, and 200 μM acetosyringone (AS) pre-cultivation of A. tumefaciens is also suggested. ATMT-mediated knockout mutagenesis was accomplished with the gene-deletion cassettes using a yeast homologous recombination method with a yeast-Escherichia-Agrobacterium shuttle vector pKOHo. Using the ATMT-mediated knockout mutagenesis, we successfully deleted three genes of H. oryzae (HoATG5, HoATG7, and HoATG8), and then got the null mutants ΔHoatg5, ΔHoatg7, and ΔHoatg8. These results suggest that ATMT is an efficient tool for gene modification including randomly insertional mutagenesis and gene deletion mutagenesis in H. oryzae.
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http://dx.doi.org/10.1016/j.micres.2015.09.008DOI Listing
January 2016

Friend or foe: differential responses of rice to invasion by mutualistic or pathogenic fungi revealed by RNAseq and metabolite profiling.

Sci Rep 2015 Sep 8;5:13624. Epub 2015 Sep 8.

State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, 310058, China.

The rice endophyte Harpophora oryzae shares a common pathogenic ancestor with the rice blast fungus Magnaporthe oryzae. Direct comparison of the interactions between a single plant species and two closely-related (1) pathogenic and (2) mutualistic fungi species can improve our understanding of the evolution of the interactions between plants and fungi that lead to either mutualistic or pathogenic interactions. Differences in the metabolome and transcriptome of rice in response to challenge by H. or M. oryzae were investigated with GC-MS, RNA-seq, and qRT-PCR. Levels of metabolites of the shikimate and lignin biosynthesis pathways increased continuously in the M. oryzae-challenged rice roots (Mo-roots); these pathways were initially induced, but then suppressed, in the H. oryzae-challenged rice roots (Ho-roots). Compared to control samples, concentrations of sucrose and maltose were reduced in the Ho-roots and Mo-roots. The expression of most genes encoding enzymes involved in glycolysis and the TCA cycle were suppressed in the Ho-roots, but enhanced in the Mo-roots. The suppressed glycolysis in Ho-roots would result in the accumulation of glucose and fructose which was not detected in the Mo-roots. A novel co-evolution pattern of fungi-host interaction is proposed which highlights the importance of plant host in the evolution of fungal symbioses.
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http://dx.doi.org/10.1038/srep13624DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4642567PMC
September 2015

The rice endophyte Harpophora oryzae genome reveals evolution from a pathogen to a mutualistic endophyte.

Sci Rep 2014 Jul 22;4:5783. Epub 2014 Jul 22.

State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, 310058, China.

The fungus Harpophora oryzae is a close relative of the pathogen Magnaporthe oryzae and a beneficial endosymbiont of wild rice. Here, we show that H. oryzae evolved from a pathogenic ancestor. The overall genomic structures of H. and M. oryzae were found to be similar. However, during interactions with rice, the expression of 11.7% of all genes showed opposing trends in the two fungi, suggesting differences in gene regulation. Moreover, infection patterns, triggering of host defense responses, signal transduction and nutritional preferences exhibited remarkable differentiation between the two fungi. In addition, the H. oryzae genome was found to contain thousands of loci of transposon-like elements, which led to the disruption of 929 genes. Our results indicate that the gain or loss of orphan genes, DNA duplications, gene family expansions and the frequent translocation of transposon-like elements have been important factors in the evolution of this endosymbiont from a pathogenic ancestor.
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http://dx.doi.org/10.1038/srep05783DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4105740PMC
July 2014

Evidence for biotrophic lifestyle and biocontrol potential of dark septate endophyte Harpophora oryzae to rice blast disease.

PLoS One 2013 18;8(4):e61332. Epub 2013 Apr 18.

State Key Laboratory for Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, China.

The mutualism pattern of the dark septate endophyte (DSE) Harpophora oryzae in rice roots and its biocontrol potential in rice blast disease caused by Magnaporthe oryzae were investigated. Fluorescent protein-expressing H. oryzae was used to monitor the colonization pattern. Hyphae invaded from the epidermis to the inner cortex, but not into the root stele. Fungal colonization increased with root tissue maturation, showing no colonization in the meristematic zone, slight colonization in the elongation zone, and heavy colonization in the differentiation zone. H. oryzae adopted a biotrophic lifestyle in roots accompanied by programmed cell death. Real-time PCR facilitated the accurate quantification of fungal growth and the respective plant response. The biocontrol potential of H. oryzae was visualized by inoculation with eGFP-tagged M. oryzae in rice. H. oryzae protected rice from M. oryzae root invasion by the accumulation of H2O2 and elevated antioxidative capacity. H. oryzae also induced systemic resistance against rice blast. This systemic resistance was mediated by the OsWRKY45-dependent salicylic acid (SA) signaling pathway, as indicated by the strongly upregulated expression of OsWRKY45. The colonization pattern of H. oryzae was consistent with the typical characteristics of DSEs. H. oryzae enhanced local resistance by reactive oxygen species (ROS) and high antioxidative level and induced OsWRKY45-dependent SA-mediated systemic resistance against rice blast.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0061332PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3630206PMC
December 2013

[Effects of the volatiles from different tomato varieties on host selection behavior of B-biotype Bemisia tabaci].

Ying Yong Sheng Tai Xue Bao 2012 Sep;23(9):2509-14

Institute of Insect sciences, Zhejiang University, Hangzhou 310058, China.

By the methods of headspace solid-phase micro extraction and gas chromatography-mass spectrometry, and using Y-type olfactometer, this paper identified the volatiles from six tomato varieties (Zheza 809, Zheza 203, Hezuo 903, Kate No. 1, Huangtuoyan, and Jinfei), and bio-assayed the olfactory responses of female B-biotype Bemisia tabaci to the tomato plants and their released volatiles. Thirteen kinds of compounds in the volatiles collected from the six tomato varieties were identified, among which, terpenoids were the main components. However, the compositions and contents of the volatiles differed with tomato varieties. (+)-3-carene and beta-caryophyllene showed stronger repellency than other terpenoids to B-type B. tabaci. B-type B. tabaci showed the lowest preference to the tomato varieties such as Zheza 809 and Zheza 203 which contained more kinds of terpenoids and had higher proportion of terpenoids in the volatiles, and showed the greatest preference to the varieties like Huangtuoyan and Jinfei which contained fewer kinds of terpenoids and had lower proportion of terpenoids in the volatiles.
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September 2012

Evaluation of methane oxidation activity in waste biocover soil during landfill stabilization.

Chemosphere 2012 Oct 7;89(6):672-9. Epub 2012 Jul 7.

Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, China.

Biocover soil has been demonstrated to have high CH(4) oxidation capacity and is considered as a good alternative cover material to mitigate CH(4) emission from landfills, yet the response of CH(4) oxidation activity of biocover soils to the variation of CH(4) loading during landfill stabilization is poorly understood. Compared with a landfill cover soil (LCS) collected from Hangzhou Tianziling landfill cell, the development of CH(4) oxidation activity of waste biocover soil (WBS) was investigated using simulated landfill systems in this study. Although a fluctuation of influent CH(4) flux occurred during landfill stabilization, the WBS covers showed a high CH(4) removal efficiency of 94-96% during the entire experiment. In the LCS covers, the CH(4) removal efficiencies varied with the fluctuation of CH(4) influent flux, even negative ones occurred due to the storage of CH(4) in the soil porosities after the high CH(4) influent flux of ~137 gm(-2) d(-1). The lower concentrations of O(2) and CH(4) as well as the higher concentration of CO(2) were observed in the WBS covers than those in the LCS covers. The highest CH(4) oxidation rates of the two types of soil covers both occurred in the bottom layer (20-30 cm). Compared to the LCS, the WBS showed higher CH(4) oxidation activity and methane monooxygenase activity over the course of the experiment. Overall, this study indicated the WBS worked well for the fluctuation of CH(4) influent flux during landfill stabilization.
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http://dx.doi.org/10.1016/j.chemosphere.2012.06.008DOI Listing
October 2012

In vitro and in vivo antifungal activity of a water-dilutable cassia oil microemulsion against Geotrichum citri-aurantii.

J Sci Food Agric 2012 Oct 13;92(13):2668-71. Epub 2012 Jun 13.

Department of Food Science and Nutrition, Zijingang Campus, Zhejiang University, Hangzhou 310058, China.

Background: Recently, food-grade microemulsions have been of increasing interest to researchers and have shown great potential in industrial applications. In this study a food-grade water-dilutable microemulsion system with cassia oil as oil, ethanol as cosurfactant, Tween 20 as surfactant and water was developed and its antifungal activity in vitro and in vivo against Geotrichum citri-aurantii was assessed.

Results: The phase diagram results confirmed the feasibility of forming a water-dilutable microemulsion based on cassia oil. One microemulsion formulation, cassia oil/ethanol/Tween 20 = 1:3:6 (w/w/w), was selected with the capability to undergo full dilution with water. The average particle size was 6.3 nm. The in vitro antifungal experiments showed that the microemulsion inhibited fungal growth on solid medium and prevented arthroconidium germination in liquid medium and that cassia oil had stronger activity when encapsulated in the microemulsion. The in vivo antifungal experiments indicated that the water-dilutable microemulsion was effective in preventing postharvest diseases of citrus fruits caused by G. citri-aurantii.

Conclusion: The results of this study suggest a promising utilisation of water-dilutable microemulsions based on essential oils for the control of postharvest diseases.
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http://dx.doi.org/10.1002/jsfa.5686DOI Listing
October 2012

Distinctive endophytic fungal assemblage in stems of wild rice (Oryza granulata) in China with special reference to two species of Muscodor (Xylariaceae).

J Microbiol 2011 Feb 3;49(1):15-23. Epub 2011 Mar 3.

Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Ministry of Agriculture, Institute of Biotechnology, Zhejiang University, Hangzhou, 310029, PR China.

Ecological niches in the rhizosphere and phyllosphere of grasses capable of sustaining endophytes have been extensively studied. In contrast, little information regarding the identity and functions of endophytic fungi in stems is available. In this study, we investigated the taxonomic affinities, diversity, and host specificities of culturable endophytes in stems of wild rice (Oryza granulata) in China. Seventy-four isolates were recovered. Low recovery rate (11.7%) indicated that there were relatively few sites for fungal infection. Identification using morphology, morphospecies sorting, and molecular techniques resulted in classification into 50 taxa, 36 of which were recovered only once. Nucleotide sequence similarity analysis indicated that 30% of the total taxa recovered were highly divergent from known species and thus may represent lineages new to science. Most of the taxa were classified as members of the classes Sordariomycetes or Dothideomycetes (mainly in Pleosporales). The presence of Arthrinium and Magnaporthaceae species, most often associated with poaceous plants, suggested a degree of host specificity. A polyphasic approach was employed to identify two Muscodor taxa based on (i) ITS and RPB2 phylogenies, (ii) volatile compounds produced, and (iii) an in vitro bioassay of antifungal activity. This to our knowledge is only the second report regarding the isolation of Muscodor spp. in China. Therefore, we hypothesize that wild plants represent a huge reservoir of unknown fungi. The prevalence, novelty, and species-specificity of unique isolates necessitate a reevaluation of their contribution to ecosystem function and fungal biodiversity.
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http://dx.doi.org/10.1007/s12275-011-0213-3DOI Listing
February 2011

Muscodor fengyangensis sp. nov. from southeast China: morphology, physiology and production of volatile compounds.

Fungal Biol 2010 Oct 29;114(10):797-808. Epub 2010 Jul 29.

Institute of Biotechnology, Zhejiang University, Hangzhou, China.

The fungal genus Muscodor was erected on the basis of Muscodor albus, an endophytic fungus originally isolated from Cinnamomum zeylanicum. It produces a mixture of volatile organic compounds (VOCs) with antimicrobial activity that can be used as mycofumigants. The genus currently comprises five species. Here we describe the isolation and characterization of a new species of Muscodor on the basis of five endophytic fungal strains from leaves of Actinidia chinensis, Pseudotaxus chienii and an unidentified broad leaf tree in the Fengyangshan Nature Reserve, Zhejiang Province, Southeast of China. They exhibit white colonies on potato dextrose agar (PDA) media, rope-like mycelial strands, but did not sporulate. The optimum growth temperature is 25°C. The results of a phylogenetic analysis based on four loci (ITS1-5.8S-ITS2, 28S rRNA, rpb2 and tub1) are consistent with the hypothesis that these five strains belong to a single taxon. All five strains also produce volatile chemical components with antimicrobial activity in vitro, which were different from those previously described for other Muscodor species.
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http://dx.doi.org/10.1016/j.funbio.2010.07.006DOI Listing
October 2010

[Value of 3D 1H-MRS with body coil at 3T in the differential diagnosis of the prostate cancer].

Zhonghua Nan Ke Xue 2009 May;15(5):431-6

Department of Urology, The First Affiliated Hospital of SUN Yat-sen University, Guangzhou, Guangdong 510080, China.

Objective: To assess the value of three dimensional proton magnetic resonance spectroscopy (3D 1H-MRS) with body coil at 3T in the differential diagnosis of prostate cancer.

Methods: Forty patients suspected of prostate cancer underwent MRI and MRS examinations, and then transrectal ultrasound guided prostate biopsy for pathological diagnosis. The MRI and MRS features of benign prostate hyperplasia, prostate cancer and prostatic intraepithelial neoplasia (PIN) were analyzed in comparison with the pathological reports, and the receiver operating characteristic curve was drawn for the diagnosis of cancer from peripheral zones.

Results: The examinations were accomplished for all the patients. The mean ratios of (Cho + Cre)/Cit in the interstitial and glandular hyperplasia tissues, the cancer tissue of the central and peripheral glands, the healthy peripheral gland and PIN were 0.75 +/- 0.23, 0.59 +/- 0.14, 1.79 +/- 0.90, 1.18 +/- 0.95, 0.46 +/- 0.18, and 0.97 +/- 0.10, respectively, with statistically significant differences between the cancer and normal prostate tissues (P < 0.01). The optimum threshold for the diagnosis of prostate cancer in the peripheral zone was 0.68 with a sensitivity of 88.6% and a specificity of 88.7%.

Conclusion: The 3D 1H-MRS with body coil at 3T has a high sensitivity and specificity in the differential diagnosis of prostate cancer, and can provide valuable information for the diagnosis of PIN.
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May 2009

Clavatol and patulin formation as the antagonistic principle of Aspergillus clavatonanicus, an endophytic fungus of Taxus mairei.

Appl Microbiol Biotechnol 2008 Apr 4;78(5):833-40. Epub 2008 Mar 4.

Institute of Biotechnology, Zhejiang University, Hangzhou 310029, China.

Many endophytic fungi are known to protect plants from plant pathogens, but the antagonistic mechanism has rarely been revealed. In this study, we wished to learn whether an endophytic Aspergillus sp., isolated from Taxus mairei, would indeed produce bioactive components, and if so whether (a) they would antagonize plant pathogenic fungi; and (b) whether this Aspergillus sp. would produce the compound also under conditions of confrontation with these fungi. The endophytic fungal strain from T. mairei was identified as Aspergillus clavatonanicus by analysis of morphological characteristics and the sequence of the internal transcribed spacers (ITS rDNA) of rDNA. When grown in surface culture, the fungus produced clavatol (2',4'-dihydroxy-3',5'-dimethylacetophenone) and patulin (2-hydroxy-3,7-dioxabicyclo [4.3.0]nona-5,9-dien-8-one), as shown by shown by NMR, MS, X-ray, and EI-MS analysis. Both exhibited inhibitory activity in vitro against several plant pathogenic fungi, i.e., Botrytis cinerea, Didymella bryoniae, Fusarium oxysporum f. sp. cucumerinum, Rhizoctonia solani, and Pythium ultimum. During confrontation with P. ultimum, A. clavatonanicus antagonized its growth of P. ultimum, and both clavatol as well as patulin were formed as the only bioactive components, albeit with different kinetics. We conclude that A. clavatonanicus produces clavatol and patulin, and that these two polyketides may be involved in the protection of T. mairei against attack by plant pathogens by this Aspergillus sp.
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http://dx.doi.org/10.1007/s00253-008-1371-zDOI Listing
April 2008