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Sample records for cultured lichen symbionts

  1. Exploring symbiont management in lichens.

    Science.gov (United States)

    Grube, Martin; Spribille, Toby

    2012-07-01

    Lichens are unique among fungal symbioses in that their mycelial structures are compact and exposed to the light as thallus structures. The myriad intersections of unique fungal species with photosynthetic partner organisms (green algae in 90% of lichens) produce a wide variety of diverse shapes and colours of the fully synthesized lichen thallus when growing in nature. This characteristic complex morphology is, however, not achieved in the fungal axenic state. Even under ideal environmental conditions, the lichen life cycle faces considerable odds: first, meiotic spores are only produced on well-established thalli and often only after achieving considerable age in a stable environment, and second, even then in vivo resynthesis requires the presence of compatible algal strains where fungal spores germinate. Many lichen species have evolved a way around the resynthesis bottleneck by producing asexual propagules for joint propagation of symbionts. These different dispersal strategies ostensibly shape the population genetic structure of lichen symbioses, but the relative contributions of vertical (joint) and horizontal (independent) symbiont transmission have long eluded lichen evolutionary biologists. In this issue of Molecular Ecology, Dal Grande et al. (2012) close in on this question with the lung lichen, Lobaria pulmonaria, a flagship species in the conservation of old growth forests. By capitalizing on available microsatellite markers for both fungal and algal symbionts, they show that while vertical transmission is the predominant mode of reproduction, horizontal transmission is demonstrable and actively shapes population genetic structure. The resulting mixed propagation system is a highly successful balance of safe recruitment of symbiotic clones and endless possibilities for fungal recombination and symbiont shuffling.

  2. Accumulation of radionuclides by lichen symbionts

    Energy Technology Data Exchange (ETDEWEB)

    Nifontova, M G; Kulikov, N V [AN SSSR, Sverdlovsk. Inst. Ehkologii Rastenij i Zhivotnykh

    1983-01-01

    The aim of investigation is the quantitative estimation of ability and role of separate symbionts in the accumulation of radionuclides. As investigation volumes, durably cultivated green lichen alga Trebouxia erici and lichen fungi extracted from Cladonia rangiferina, Parmelia caperata and Acarospora fuscata are used. The accumulation of radioactive isotopes with fungi and seaweeds is estimated according to accumulation coefficients (AC) which are the ratio of radiation concentration in plants and agarized medium. Radionuclide content (/sup 90/Sr and /sup 137/Cs) is determined radiometrically. A special series of experiments is done to investigate radionuclide accumulation dependences with lichen seaweed and fungi on light conditions. It is shown that both symbionts of lichen-seaweed and fungus take part in the accumulation of radionuclide from outer medium (atmospheric fall-out and soil). However fungus component constituting the base of structural organization of thallus provides the greater part of radionuclides accumulated by the plant. Along with this the violation of viability of seaweed symbionts particularly in the case of light deficiency brings about the reduction of /sup 137/Cs sorption by seaweeds and tells on the total content of radiocesium in plant thallus.

  3. Isolation of symbionts and GC-MS analysis of lichens collected from ...

    African Journals Online (AJOL)

    In Nigeria, a good number of lichen species have been recorded and so far not much work has been done to isolate or identify the symbionts. The utility of lichen comes from a range of secondary compounds produced by them. In view of this, two lichen samples, foliose (Parmalia reticulata Taylor) and fruticose Usnea ...

  4. Lichens

    Energy Technology Data Exchange (ETDEWEB)

    Kershaw, K A

    1963-01-01

    The extreme susceptibility of lichens to air pollution is emphasized in a discussion of the distribution and ecology of the symbionts. The susceptibility is possible due to the indiscriminate and rapid absorption of solutes over the surface of the thallus. Lichens are virtually absent from towns and industrial areas. In an investigation in Kvarntorp, Sweden, the distribution of lichens corresponded markedly with the levels of air pollution, mainly by sulfur dioxide and secondly to the low humidity of the area. There are a few lichens that are tolerant of pollution and occur abundantly in industrial and suburban areas. Lecandra conizaeoides and Stereocaulton pileatum are prevalent in large cities of Great Britain and are early colonizers of trees and brickwork. The apparent preference of lichens for asbestos roofing in polluted areas is related to the high water absorbing power of the substratum and the high base content, with the consequent power of neutralizing acidic atmospheric pollutants. The flora growing on an asbestos tiled roof eight miles from London was examined and revealed four species: S. muralis, L. dispersa, R. demissa, and C. vitellina. The density of the S. muralis was approximately 1/sq m with diameters up to 6 cm. The density of the other species was extremely high, up to 368 apothecia/sq cm for L. dispersa. The figures suggest that the high water absorbing properties and basicity of the asbestos are the factors responsible for the prolific lichen growth. 15 references, 13 figures.

  5. Innovative Approaches Using Lichen Enriched Media to Improve Isolation and Culturability of Lichen Associated Bacteria.

    Science.gov (United States)

    Biosca, Elena G; Flores, Raquel; Santander, Ricardo D; Díez-Gil, José Luis; Barreno, Eva

    2016-01-01

    Lichens, self-supporting mutualistic associations between a fungal partner and one or more photosynthetic partners, also harbor non-photosynthetic bacteria. The diversity and contribution of these bacteria to the functioning of lichen symbiosis have recently begun to be studied, often by culture-independent techniques due to difficulties in their isolation and culture. However, culturing as yet unculturable lichenic bacteria is critical to unravel their potential functional roles in lichen symbiogenesis, to explore and exploit their biotechnological potential and for the description of new taxa. Our objective was to improve the recovery of lichen associated bacteria by developing novel isolation and culture approaches, initially using the lichen Pseudevernia furfuracea. We evaluated the effect of newly developed media enriched with novel lichen extracts, as well as the influence of thalli washing time and different disinfection and processing protocols of thalli. The developed methodology included: i) the use of lichen enriched media to mimic lichen nutrients, supplemented with the fungicide natamycin; ii) an extended washing of thalli to increase the recovery of ectolichenic bacteria, thus allowing the disinfection of thalli to be discarded, hence enhancing endolichenic bacteria recovery; and iii) the use of an antioxidant buffer to prevent or reduce oxidative stress during thalli disruption. The optimized methodology allowed significant increases in the number and diversity of culturable bacteria associated with P. furfuracea, and it was also successfully applied to the lichens Ramalina farinacea and Parmotrema pseudotinctorum. Furthermore, we provide, for the first time, data on the abundance of culturable ecto- and endolichenic bacteria that naturally colonize P. furfuracea, R. farinacea and P. pseudotinctorum, some of which were only able to grow on lichen enriched media. This innovative methodology is also applicable to other microorganisms inhabiting these

  6. Innovative Approaches Using Lichen Enriched Media to Improve Isolation and Culturability of Lichen Associated Bacteria

    Science.gov (United States)

    Biosca, Elena G.; Flores, Raquel; Santander, Ricardo D.; Díez-Gil, José Luis; Barreno, Eva

    2016-01-01

    Lichens, self-supporting mutualistic associations between a fungal partner and one or more photosynthetic partners, also harbor non-photosynthetic bacteria. The diversity and contribution of these bacteria to the functioning of lichen symbiosis have recently begun to be studied, often by culture-independent techniques due to difficulties in their isolation and culture. However, culturing as yet unculturable lichenic bacteria is critical to unravel their potential functional roles in lichen symbiogenesis, to explore and exploit their biotechnological potential and for the description of new taxa. Our objective was to improve the recovery of lichen associated bacteria by developing novel isolation and culture approaches, initially using the lichen Pseudevernia furfuracea. We evaluated the effect of newly developed media enriched with novel lichen extracts, as well as the influence of thalli washing time and different disinfection and processing protocols of thalli. The developed methodology included: i) the use of lichen enriched media to mimic lichen nutrients, supplemented with the fungicide natamycin; ii) an extended washing of thalli to increase the recovery of ectolichenic bacteria, thus allowing the disinfection of thalli to be discarded, hence enhancing endolichenic bacteria recovery; and iii) the use of an antioxidant buffer to prevent or reduce oxidative stress during thalli disruption. The optimized methodology allowed significant increases in the number and diversity of culturable bacteria associated with P. furfuracea, and it was also successfully applied to the lichens Ramalina farinacea and Parmotrema pseudotinctorum. Furthermore, we provide, for the first time, data on the abundance of culturable ecto- and endolichenic bacteria that naturally colonize P. furfuracea, R. farinacea and P. pseudotinctorum, some of which were only able to grow on lichen enriched media. This innovative methodology is also applicable to other microorganisms inhabiting these

  7. Lichens

    Science.gov (United States)

    Rodriguez, Cynthia M; Bennett, James P

    2012-01-01

    The prion diseases sheep scrapie and cervid chronic wasting disease are transmitted, in part, via an environmental reservoir of infectivity; prions released from infected animals persist in the environment and can cause disease years later. Central to controlling disease transmission is the identification of methods capable of inactivating these agents on the landscape. We have found that certain lichens, common, ubiquitous, symbiotic organisms, possess a serine protease capable of degrading prion protein (PrP) from prion-infected animals. The protease functions against a range of prion strains from various hosts and reduces levels of abnormal PrP by at least two logs. We have now tested more than twenty lichen species from several geographical locations and from various taxa and found that approximately half of these species degrade PrP. Critical next steps include examining the effect of lichens on prion infectivity and cloning the protease responsible for PrP degradation. The impact of lichens on prions in the environment remains unknown. We speculate that lichens could have the potential to degrade prions when they are shed from infected animals onto lichens or into environments where lichens are abundant. In addition, lichens are frequently consumed by cervids and many other animals and the effect of dietary lichens on prion disease transmission should also be considered. PMID:22453171

  8. Antigenic similarities and differences between symbiotic and cultured phycobionts from the lichen, Xanthoria parietina

    International Nuclear Information System (INIS)

    Bubrick, P.; Galun, M.; Ben-Yaacov, M.; Frensdorff, A.

    1982-01-01

    Lichen phycobionts are known to undergo a series of morphological, physiological, and biochemical changes as a result of lichenization. A number of modifications in the cell wall of lichen algae have also been described. Using the phycobiont of Xanthoria parietina as a study organism. The authors have shown that concanavalin A bound to the cell wall of lichen algae cultured in vitro, but not to the same algae in the symbiotic form (freshly isolated from the lichen). They have also isolated a crude protein fraction from the lichen, a component(s) of which bound to the cell wall of cultured, but not freshly isolated algae. Binding was correlated to cytochemical features present only on the cell wall of cultured algae. With the aid of a newly-developed solid-phase radioimmunoassay, the authors show that there are also detectable antigenic differences, as well as similarities, between freshly isolated and cultured phycobionts from X. parietina. (Auth.)

  9. Antigenic similarities and differences between symbiotic and cultured phycobionts from the lichen, Xanthoria parietina

    Energy Technology Data Exchange (ETDEWEB)

    Bubrick, P; Galun, M [Tel Aviv Univ. (Israel). Dept. of Botany; Ben-Yaacov, M; Frensdorff, A [Tel-Aviv Univ. (Israel). Dept. of Microbiology

    1982-04-01

    Lichen phycobionts are known to undergo a series of morphological, physiological, and biochemical changes as a result of lichenization. A number of modifications in the cell wall of lichen algae have also been described. Using the phycobiont of Xanthoria parietina as a study organism. The authors have shown that concanavalin A bound to the cell wall of lichen algae cultured in vitro, but not to the same algae in the symbiotic form (freshly isolated from the lichen). They have also isolated a crude protein fraction from the lichen, a component(s) of which bound to the cell wall of cultured, but not freshly isolated algae. Binding was correlated to cytochemical features present only on the cell wall of cultured algae. With the aid of a newly-developed solid-phase radioimmunoassay, the authors show that there are also detectable antigenic differences, as well as similarities, between freshly isolated and cultured phycobionts from X. parietina.

  10. Fungal specificity and selectivity for algae play a major role in determining lichen partnerships across diverse ecogeographic regions in the lichen-forming family Parmeliaceae (Ascomycota).

    Science.gov (United States)

    Leavitt, Steven D; Kraichak, Ekaphan; Nelsen, Matthew P; Altermann, Susanne; Divakar, Pradeep K; Alors, David; Esslinger, Theodore L; Crespo, Ana; Lumbsch, Thorsten

    2015-07-01

    Microbial symbionts are instrumental to the ecological and long-term evolutionary success of their hosts, and the central role of symbiotic interactions is increasingly recognized across the vast majority of life. Lichens provide an iconic group for investigating patterns in species interactions; however, relationships among lichen symbionts are often masked by uncertain species boundaries or an inability to reliably identify symbionts. The species-rich lichen-forming fungal family Parmeliaceae provides a diverse group for assessing patterns of interactions of algal symbionts, and our study addresses patterns of lichen symbiont interactions at the largest geographic and taxonomic scales attempted to date. We analysed a total of 2356 algal internal transcribed spacer (ITS) region sequences collected from lichens representing ten mycobiont genera in Parmeliaceae, two genera in Lecanoraceae and 26 cultured Trebouxia strains. Algal ITS sequences were grouped into operational taxonomic units (OTUs); we attempted to validate the evolutionary independence of a subset of the inferred OTUs using chloroplast and mitochondrial loci. We explored the patterns of symbiont interactions in these lichens based on ecogeographic distributions and mycobiont taxonomy. We found high levels of undescribed diversity in Trebouxia, broad distributions across distinct ecoregions for many photobiont OTUs and varying levels of mycobiont selectivity and specificity towards the photobiont. Based on these results, we conclude that fungal specificity and selectivity for algal partners play a major role in determining lichen partnerships, potentially superseding ecology, at least at the ecogeographic scale investigated here. To facilitate effective communication and consistency across future studies, we propose a provisional naming system for Trebouxia photobionts and provide representative sequences for each OTU circumscribed in this study. © 2015 John Wiley & Sons Ltd.

  11. Effects of Growth Media on the Diversity of Culturable Fungi from Lichens

    Directory of Open Access Journals (Sweden)

    Lucia Muggia

    2017-05-01

    Full Text Available Microscopic and molecular studies suggest that lichen symbioses contain a plethora of associated fungi. These are potential producers of novel bioactive compounds, but strains isolated on standard media usually represent only a minor subset of these fungi. By using various in vitro growth conditions we are able to modulate and extend the fraction of culturable lichen-associated fungi. We observed that the presence of iron, glucose, magnesium and potassium in growth media is essential for the successful isolation of members from different taxonomic groups. According to sequence data, most isolates besides the lichen mycobionts belong to the classes Dothideomycetes and Eurotiomycetes. With our approach we can further explore the hidden fungal diversity in lichens to assist in the search of novel compounds.

  12. Effects of Growth Media on the Diversity of Culturable Fungi from Lichens.

    Science.gov (United States)

    Muggia, Lucia; Kopun, Theodora; Grube, Martin

    2017-05-17

    Microscopic and molecular studies suggest that lichen symbioses contain a plethora of associated fungi. These are potential producers of novel bioactive compounds, but strains isolated on standard media usually represent only a minor subset of these fungi. By using various in vitro growth conditions we are able to modulate and extend the fraction of culturable lichen-associated fungi. We observed that the presence of iron, glucose, magnesium and potassium in growth media is essential for the successful isolation of members from different taxonomic groups. According to sequence data, most isolates besides the lichen mycobionts belong to the classes Dothideomycetes and Eurotiomycetes. With our approach we can further explore the hidden fungal diversity in lichens to assist in the search of novel compounds.

  13. Radical scavenging, prolyl endopeptidase inhibitory, and antimicrobial potential of a cultured Himalayan lichen Cetrelia olivetorum.

    Science.gov (United States)

    Savale, Swapnil Anil; Pol, Chaitrali Satish; Khare, Roshni; Verma, Neeraj; Gaikwad, Subhash; Mandal, Bapi; Behera, Bhaskar C

    2016-01-01

    Lichens are source of natural bioactive compounds which are traditionally used to cure a variety of ailments. The objective of this study is to assess free radical scavenging, prolyl endopeptidase inhibitory (PEPI), and antimicrobial potential of a high altitude lichen species Cetrelia olivetorum (Nyl.) W. L. Culb. & C. F. Culb (Parmeliaceae). Lichen C. olivetorum has been cultured in vitro, and optimized culture conditions were implemented in bioreactor to obtain high quantity of biomass for the study of radical scavenging, PEPI, and antimicrobial activities. Radical scavenging activity of methanol extract of Cetrelia olivetorum (MECO) was tested at 100 µg/mL, PEPI activity at 25 and 50 µg/mL, and antimicrobial activity at 5, 25, 50, and 100 µg/mL conc. All the biological activities of natural thallus extract and its derived culture extract were evaluated spectrophotometrically. Murashige and Skoog medium supplemented with 3% glucose and 100 ppb indole-3-butyric acid (IBA) supported biomass growth at flask level and yielded 5.095 g biomass in bioreactor. MECO of both the cultured and the natural lichen exhibited half inhibiting concentration (IC50) for radical scavenging activities in the range of 50-60 µg/mL, whereas the IC50 value of standard antioxidants was found to be in the range of 12-29 µg/mL. The IC50 value of lichen extract for PEPI activity was 144-288 µg/mL, whereas the IC50 value of standard prolyl endopeptidase inhibitor, Z-pro-prolinal, was 57.73 µg/mL. As far as the antimicrobial activity of MECO is concerned, minimum inhibitory concentration (MIC) value of lichen extracts against tested microorganisms was obtained in the range of 50-104 µg/mL and found to be more effective than commercially available standard erythromycin. Murashige and Skoog medium containing IBA was found to be suitable for maximum biomass production of C. olivetorum under bioreactor conditions. The cultured lichen biomass extract also showed

  14. Phenyl ethers from cultured lichen mycobionts of Graphis scripta var. serpentina and G. rikuzensis.

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    Takenaka, Yukiko; Tanahashi, Takao; Nagakura, Naotaka; Hamada, Nobuo

    2003-07-01

    Spore-derived mycobionts of the lichen Graphis scripta var. serpentina and G. rikuzensis were cultivated on a malt-yeast extract medium supplemented with 10% sucrose and their metabolites were investigated. 3,3'-Dihydroxy-5,5'-dimethyldiphenyl ether was isolated from the cultures of the mycobionts of G. scripta var. serpentina, while a new phenyl ether, rikuzenol, along with two known diphenyl ethers, violaceol-I and violaceol-II, were isolated from those of G. rikuzensis. The structure of the new compound was determined by spectroscopic methods. Violaceol-I was chemically synthesized and interconversion between violaceol-I and violaceol-II was proven.

  15. Lichen Sclerosus

    Science.gov (United States)

    Lichen sclerosus Overview Lichen sclerosus (LIE-kun skluh-ROW-sus) is an uncommon condition that creates patchy, white skin that's thinner than normal. Lichen sclerosus can affect skin anywhere on your body. ...

  16. Lichen Nitidus

    Science.gov (United States)

    Lichen nitidus Overview Lichen nitidus (LIE-kun ni-TIE-dus) is a rare skin condition that usually appears as tiny, skin-colored, glistening bumps on the surface of your skin. Lichen nitidus results from abnormal inflammatory activity in skin ...

  17. Learning Lichens

    Science.gov (United States)

    Thorne, Sarah

    2017-01-01

    The lichen is an ideal subject for student study because it is omnipresent in school yards, easily collected and observed year-round, a pioneer of evolution on land, and a bioindicator of air pollution. After doing fieldwork on this unusual composite organism as an apprentice with a team of lichenologists, Sarah Thorne developed Learning Lichens.…

  18. Esophageal lichen planus

    OpenAIRE

    Oliveira, Janine Pichler de; Uribe, Natalia Caballero; Abulafia, Luna Azulay; Quintella, Leonardo Pereira

    2015-01-01

    Abstract Lichen planus is a chronic inflammatory disease that affects the skin, mucous membranes, nails and scalp. Esophageal lichen planus is a rarely reported manifestation of lichen planus, presenting itself commonly in middle-aged women, with symptoms such as dysphagia. We report a case of esophageal lichen planus in a 54-year-old woman associated with oral, cutaneous and ungual lichen planus. Although lichen planus is a disorder well known by dermatologists, reports of esophageal lichen ...

  19. Microbiome change by symbiotic invasion in lichens

    Science.gov (United States)

    Maier, Stefanie; Wedin, Mats; Fernandez-Brime, Samantha; Cronholm, Bodil; Westberg, Martin; Weber, Bettina; Grube, Martin

    2016-04-01

    Biological soil crusts (BSC) seal the soil surface from erosive forces in many habitats where plants cannot compete. Lichens symbioses of fungi and algae often form significant fraction of these microbial assemblages. In addition to the fungal symbiont, many species of other fungi can inhabit the lichenic structures and interact with their hosts in different ways, ranging from commensalism to parasitism. More than 1800 species of lichenicolous (lichen-inhabiting) fungi are known to science. One example is Diploschistes muscorum, a common species in lichen-dominated BSC that infects lichens of the genus Cladonia. D. muscorum starts as a lichenicolous fungus, invading the lichen Cladonia symphycarpa and gradually develops an independent Diploschistes lichen thallus. Furthermore, bacterial groups, such as Alphaproteobacteria and Acidobacteria, have been consistently recovered from lichen thalli and evidence is rapidly accumulating that these microbes may generally play integral roles in the lichen symbiosis. Here we describe lichen microbiome dynamics as the parasitic lichen D. muscorum takes over C. symphycarpa. We used high-throughput 16S rRNA gene and photobiont-specific ITS rDNA sequencing to track bacterial and algal transitions during the infection process, and employed fluorescence in situ hybridization to localize bacteria in the Cladonia and Diploschistes lichen thalli. We sampled four transitional stages, at sites in Sweden and Germany: A) Cladonia with no visible infection, B) early infection stage defined by the first visible Diploschistes thallus, C) late-stage infection with parts of the Cladonia thallus still identifiable, and D) final stage with a fully developed Diploschistes thallus, A gradual microbiome shift occurred during the transition, but fractions of Cladonia-associated bacteria were retained during the process of symbiotic reorganization. Consistent changes observed across sites included a notable decrease in the relative abundance of

  20. Lichen planus

    NARCIS (Netherlands)

    van der Waal, I.

    2014-01-01

    Lichen planus komt niet zelden in het mondslijmvlies voor. De meeste tandartsen en mondhygiënisten zullen zich daarbij witte lijntjes beiderzijds op het wangslijmvlies voor de geest halen. Iedereen zal wel zeggen zo’n patiënt in de praktijk in zijn bestand te hebben, maar vermoedelijk wordt het

  1. What Is Lichen Sclerosus?

    Science.gov (United States)

    ... Outreach Initiative Breadcrumb Home Health Topics English Español Lichen Sclerosus Basics In-Depth Download Download EPUB Download PDF What is it? Points To Remember About Lichen Sclerosus Lichen sclerosus usually affects the skin of ...

  2. Esophageal lichen planus.

    Science.gov (United States)

    Oliveira, Janine Pichler de; Uribe, Natalia Caballero; Abulafia, Luna Azulay; Quintella, Leonardo Pereira

    2015-01-01

    Lichen planus is a chronic inflammatory disease that affects the skin, mucous membranes, nails and scalp. Esophageal lichen planus is a rarely reported manifestation of lichen planus, presenting itself commonly in middle-aged women, with symptoms such as dysphagia. We report a case of esophageal lichen planus in a 54-year-old woman associated with oral, cutaneous and ungual lichen planus. Although lichen planus is a disorder well known by dermatologists, reports of esophageal lichen planus are rare in dermatologic literature. The esophageal lichen planus is little known and underdiagnosed, with a significant delay between the onset of symptoms and diagnosis.

  3. Lichen explants and natural occurrence of lichens

    Energy Technology Data Exchange (ETDEWEB)

    Kirschbaum, A; Klee, R

    1971-01-01

    Studies with lichen explants and with naturally occurring lichens, conducted in the Lower Main region in West Germany within the framework of an air hydgienic and meteorologic model study of that region, are described. Parmelia physodes explants from oak trees growing in nonpolluted areas were exposed in polluted areas, such as in an industrial area, an airport, a petroleum refinery, and near a large chemical plant. The degree of air pollution in the exposure site was evaluated by the degree of the lichen damage in seven grades. The large-scale average distribution of air pollution in the survey area was studied by surveying the natural occurrence of lichen species on 10 apple trees in area units of 6.25 sq km each. The lichen explant and lichen survey methods compared by the study of naturally occurring lichens were near the exposure site of lichen explants.

  4. Lichen indicator [Section 4

    Science.gov (United States)

    Paul L. Patterson; Susan Will-Wolf; Marie T. Trest

    2009-01-01

    Lichens are very responsive to environmental stressors in forests, including changes in forest structure, air quality, and climate. Each lichen species on a plot is an indicator of how lichen communities respond to ecological conditions. Individual lichen species occur erratically and even common species are often absent from plots with suitable habitat. The combined...

  5. [Superimposed lichen planus pigmentosus].

    Science.gov (United States)

    Monteagudo, Benigno; Suarez-Amor, Óscar; Cabanillas, Miguel; de Las Heras, Cristina; Álvarez, Juan Carlos

    2014-05-16

    Lichen planus pigmentosus is an uncommon variant of lichen planus that is characterized by the insidious onset of dark brown macules in sun-exposed areas and flexural folds. Superimposed linear lichen planus is an exceedingly rare disorder, but it has been found in both lichen planopilaris and lichen planus types. A 39-year-old woman is presented showing a segmental and linear lichen planus associated with non-segmental lesions meeting all criteria for the diagnosis of superimposed linear planus pigmentosus. The segmental lesions were always more pronounced.

  6. Pigments Characterization and Molecular Identification of Bacterial Symbionts of Brown Algae Padinasp. Collected from Karimunjawa Island

    Directory of Open Access Journals (Sweden)

    Damar Bayu Murti

    2016-06-01

    Full Text Available The search for carotenoids in nature has been extensively studied because of their applications in foods. One treasure of the biopigment source is symbiotic-microorganisms with marine biota. The advantages of symbiont bacteria are easy to culture and sensitize pigments. The use of symbiont bacteria helps to conserve fish, coral reefs, seagrass, and seaweed. Therefore, the bacteria keeps their existence in their ecosystems. In this study, bacterial symbionts were successfully isolated from brown algae Padina sp. The bacterial symbionts had yellow pigment associated with carotenoids. The pigments were characterized using High Performance Liquid Chromatography (HPLC with a Photo Diode Array (PDA detector. The carotenoid pigments in the bacterial symbionts were identified as dinoxanthin, lutein and neoxanthin. Molecular identification by using a 16S rRNA gene sequence method, reveals that the bacterial symbionts were closely related to Bacillus marisflavi with a homology of 99%. Keywords :carotenoid pigments, brown algae, Padina, bacterial symbionts, 16S rRNA

  7. Lichen substances prevent lichens from nutrient deficiency.

    Science.gov (United States)

    Hauck, Markus; Willenbruch, Karen; Leuschner, Christoph

    2009-01-01

    The dibenzofuran usnic acid, a widespread cortical secondary metabolite produced by lichen-forming fungi, was shown to promote the intracellular uptake of Cu(2+) in two epiphytic lichens, Evernia mesomorpha and Ramalina menziesii, from acidic, nutrient-poor bark. Higher Cu(2+) uptake in the former, which produces the depside divaricatic acid in addition to usnic acid, suggests that this depside promotes Cu(2+) uptake. Since Cu(2+) is one of the rarest micronutrients, promotion of Cu(2+) uptake by lichen substances may be crucial for the studied lichens to survive in their nutrient-poor habitats. In contrast, study of the uptake of other metals in E. mesomorpha revealed that the intracellular uptake of Mn(2+), which regularly exceeds potentially toxic concentrations in leachates of acidic tree bark, was partially inhibited by the lichen substances produced by this species. Inhibition of Mn(2+) uptake by lichen substances previously has been demonstrated in lichens. The uptake of Fe(2+), Fe(3+), Mg(2+), and Zn(2+), which fail to reach toxic concentrations in acidic bark at unpolluted sites, although they are more common than Cu(2+), was not affected by lichen substances of E. mesomorpha.

  8. Cyanobacteria produce a high variety of hepatotoxic peptides in lichen symbiosis

    Science.gov (United States)

    Kaasalainen, Ulla; Fewer, David P.; Jokela, Jouni; Wahlsten, Matti; Sivonen, Kaarina; Rikkinen, Jouko

    2012-01-01

    Lichens are symbiotic associations between fungi and photosynthetic algae or cyanobacteria. Microcystins are potent toxins that are responsible for the poisoning of both humans and animals. These toxins are mainly associated with aquatic cyanobacterial blooms, but here we show that the cyanobacterial symbionts of terrestrial lichens from all over the world commonly produce microcystins. We screened 803 lichen specimens from five different continents for cyanobacterial toxins by amplifying a part of the gene cluster encoding the enzyme complex responsible for microcystin production and detecting toxins directly from lichen thalli. We found either the biosynthetic genes for making microcystins or the toxin itself in 12% of all analyzed lichen specimens. A plethora of different microcystins was found with over 50 chemical variants, and many of the variants detected have only rarely been reported from free-living cyanobacteria. In addition, high amounts of nodularin, up to 60 μg g−1, were detected from some lichen thalli. This microcystin analog and potent hepatotoxin has previously been known only from the aquatic bloom-forming genus Nodularia. Our results demonstrate that the production of cyanobacterial hepatotoxins in lichen symbiosis is a global phenomenon and occurs in many different lichen lineages. The very high genetic diversity of the mcyE gene and the chemical diversity of microcystins suggest that lichen symbioses may have been an important environment for diversification of these cyanobacteria. PMID:22451908

  9. Lichen Endozoochory by Snails

    Science.gov (United States)

    Boch, Steffen; Prati, Daniel; Werth, Silke; Rüetschi, Jörg; Fischer, Markus

    2011-01-01

    Endozoochory plays a prominent role for the dispersal of seed plants. However, for most other plant taxa it is not known whether this mode of dispersal occurs at all. Among those other taxa, lichens as symbiotic associations of algae and fungi are peculiar as their successful dispersal requires movement of propagules that leaves the symbiosis functional. However, the potential for endozoochorous dispersal of lichen fragments has been completely overlooked. We fed sterile thalli of two foliose lichen species (Lobaria pulmonaria and Physcia adscendens) differing in habitat and air-quality requirements to nine snail species common in temperate Europe. We demonstrated morphologically that L. pulmonaria regenerated from 29.0% of all 379 fecal pellets, whereas P. adscendens regenerated from 40.9% of all 433 fecal pellets, showing that lichen fragments survived gut passage of all snail species. Moreover, molecular analysis of regenerated lichens confirmed the species identity for a subset of samples. Regeneration rates were higher for the generalist lichen species P. adscendens than for the specialist lichen species L. pulmonaria. Furthermore, lichen regeneration rates varied among snail species with higher rates after gut passage of heavier snail species. We suggest that gastropods generally grazing on lichen communities are important, but so far completely overlooked, as vectors for lichen dispersal. This opens new ecological perspectives and questions the traditional view of an entirely antagonistic relationship between gastropods and lichens. PMID:21533256

  10. Oral lichen planus preceding concomitant lichen planopilaris.

    Science.gov (United States)

    Stoopler, Eric T; Alfaris, Sausan; Alomar, Dalal; Alawi, Faizan

    2016-09-01

    Lichen planus (LP) is an immune-mediated mucocutaneous disorder with a wide array of clinical presentations. Oral lichen planus (OLP) is characterized clinically by striae, desquamation, and/or ulceration. Lichen planopilaris (LPP), a variant of LP, affects the scalp, resulting in perifollicular erythema and scarring of cutaneous surfaces accompanied by hair loss. The association between OLP and LPP has been reported previously with scant information on concomitant or sequential disease presentation. We describe a patient with concomitant OLP and LPP, and to the best of our knowledge, this is the first report on OLP preceding the onset of LPP. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Can Antarctic lichens acclimatize to changes in temperature?

    Science.gov (United States)

    Colesie, Claudia; Büdel, Burkhard; Hurry, Vaughan; Green, Thomas George Allan

    2018-03-01

    The Antarctic Peninsula, a tundra biome dominated by lichens and bryophytes, is an ecozone undergoing rapid temperature shifts. Such changes may demand a high physiological plasticity of the local lichen species to maintain their role as key drivers in this pristine habitat. This study examines the response of net photosynthesis and respiration to increasing temperatures for three Antarctic lichen species with different ecological response amplitudes. We hypothesize that negative effects caused by increased temperatures can be mitigated by thermal acclimation of respiration and/or photosynthesis. The fully controlled growth chamber experiment simulated intermediate and extreme temperature increases over the time course of 6 weeks. Results showed that, in contrast to our hypothesis, none of the species was able to down-regulate temperature-driven respiratory losses through thermal acclimation of respiration. Instead, severe effects on photobiont vitality demonstrated that temperatures around 15°C mark the upper limit for the two species restricted to the Antarctic, and when mycobiont demands exceeded the photobiont capacity they could not survive within the lichen thallus. In contrast, the widespread lichen species was able to recover its homoeostasis by rapidly increasing net photosynthesis. We conclude that to understand the complete lichen response, acclimation processes of both symbionts, the photo- and the mycobiont, have to be evaluated separately. As a result, we postulate that any acclimation processes in lichen are species-specific. This, together with the high degree of response variability and sensitivity to temperature in different species that co-occur spatially close, complicates any predictions regarding future community composition in the Antarctic. Nevertheless, our results suggest that species with a broad ecological amplitude may be favoured with on-going changes in temperature. © 2017 John Wiley & Sons Ltd.

  12. Lichens in the Churchyard

    Science.gov (United States)

    Oldershaw, Cally; Hilton, Barbara; Rocca, Alis

    2010-01-01

    The late Tom Chester, in his role as the British Lichen Society churchyard coordinator, did a great deal to encourage the use of the churchyard as an educational tool. In his honour, the Society has created an award as part of its "Lichen Project". When the Society approached the Association for Science Education (ASE) for help in…

  13. The organic air pollutant cumene hydroperoxide interferes with NO antioxidant role in rehydrating lichen

    International Nuclear Information System (INIS)

    Catalá, M.; Gasulla, F.; Pradas del Real, A.E.; García-Breijo, F.; Reig-Armiñana, J.; Barreno, E.

    2013-01-01

    Organic pollutants effects on lichens have not been addressed. Rehydration is critical for lichens, a burst of free radicals involving NO occurs. Repeated dehydrations with organic pollutants could increase oxidative damage. Our aim is to learn the effects of cumene hydroperoxide (CP) during lichen rehydration using Ramalina farinacea (L.) Ach., its photobiont Trebouxia spp. and Asterochloris erici. Confocal imaging shows intracellular ROS and NO production within myco and phycobionts, being the chloroplast the main source of free radicals. CP increases ROS, NO and lipid peroxidation and reduces chlorophyll autofluorescence, although photosynthesis remains unaffected. Concomitant NO inhibition provokes a generalized increase of ROS and a decrease in photosynthesis. Our results suggest that CP induces a compensatory hormetic response in Ramalina farinacea that could reduce the lichen's antioxidant resources after repeated desiccation-rehydration cycles. NO is important in the protection from CP. -- Highlights: •Organic pollutants could be involved in lichen decline but effects are unknown. •Cumene hydroperoxide induces a compensatory response in rehydration (hormesis). •Cumene hydroperoxide induces a delayed lipid peroxidation. •NO is involved in rehydration oxidative stress regulation under cumene hydroperoxide. •Symbionts display specific responses probably involving communication along time. -- The organic air pollutant cumene hydroperoxide induces oxidative membrane damage in the lichen Ramalina farinacea during rehydration. Nitric oxide (NO) is involved in lichen response

  14. ITS1 metabarcoding highlights low specificity of lichen mycobiomes at a local scale.

    Science.gov (United States)

    Fernández-Mendoza, Fernando; Fleischhacker, Antonia; Kopun, Theodora; Grube, Martin; Muggia, Lucia

    2017-09-01

    As self-supporting and long-living symbiotic structures, lichens provide a habitat for many other organisms beside the traditionally considered lichen symbionts-the myco- and the photobionts. The lichen-inhabiting fungi either develop diagnostic phenotypes or occur asymptomatically. Because the degree of specificity towards the lichen host is poorly known, we studied the diversity of these fungi among neighbouring lichens on rocks in an alpine habitat. Using a sequencing metabarcoding approach, we show that lichen mycobiomes clearly reflect the overlap of multiple ecological sets of taxa, which differ in their trophic association with lichen thalli. The lack of specificity to the lichen mycobiome is further supported by the lack of community structure observed using clustering and ordination methods. The communities encountered across samples largely result from the subsampling of a shared species pool, in which we identify three major ecological components: (i) a generalist environmental pool, (ii) a lichenicolous/endolichenic pool and (iii) a pool of transient species. These taxa majorly belong to the fungal classes Dothideomycetes, Eurotiomycetes and Tremellomycetes with close relatives in adjacent ecological niches. We found no significant evidence that the phenotypically recognized lichenicolous fungi influence the occurrence of the other asymptomatic fungi in the host thalli. We claim that lichens work as suboptimal habitats or as a complex spore and mycelium bank, which modulate and allow the regeneration of local fungal communities. By performing an approach that minimizes ambiguities in the taxonomic assignments of fungi, we present how lichen mycobiomes are also suitable targets for improving bioinformatic analyses of fungal metabarcoding. © 2017 John Wiley & Sons Ltd.

  15. Lichen flora of Derbyshire

    Energy Technology Data Exchange (ETDEWEB)

    Hawksworth, D L

    1969-01-01

    The lichen flora of the central English county of Derbyshire is described and discussed. The distribution of each species is described with reference to 10 km grid squares. In areas where air pollution is severe, very few species are found, even if otherwise suitable habitants are available. Air pollution is therefore considered to be the dominant factor affecting the present lichen flora of the county. The lichen communities have been studied and nineteen unions belonging to eleven federations are recognized. Several species are discussed taxonomically. 182 references, 15 tables.

  16. Lichens as biological indicators

    Energy Technology Data Exchange (ETDEWEB)

    Richardson, H S

    1981-09-15

    Lichens, a symbiotic association of an alga and a fungus, have been used for some years as 'bioindicators', to detect environmental pollution. For this, their property of reacting to certain pollutants with characteristic changes of growth is exploired. With this biological method, continual, sufficiently sensitive measurements over wide areas can often be carried out more simply than with expensive, complicated technical equipment, which requires servicing, as well. This article describes the various possibilities of using lichens as bioindicators, and reviews the methods currently in use for measuring air pollution by means of lichens.

  17. Erosive Lichen Planus.

    Science.gov (United States)

    Mauskar, Melissa

    2017-09-01

    Lichen planus is an inflammatory mucocutaneous condition with a myriad of clinical manifestations. There are 3 forms of lichen planus that effect the vulva: papulosquamous, hypertrophic, and erosive. Erosive lichen planus can progress to vulvar scaring, vaginal stenosis, and squamous cell carcinoma; these long-term sequelae cause sexual distress, depression, and decreased quality of life for patients. Diagnosis is often delayed because of patient embarrassment or clinician misdiagnosis. Early recognition and treatment is essential to decreasing the morbidity of this condition. Multimodal treatment, along with a multidisciplinary approach, will improve outcomes and further clinical advances in studying this condition. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Vulval lichen planus-lichen sclerosus overlap.

    Science.gov (United States)

    Howard, Matthew; Hall, Anthony

    2018-01-01

    Vulval lichen planus-lichen sclerosus overlap is an emerging observation. Few clinical reports exist with no reviews of literature. We present a focused update of this phenomenon and discuss a clinical case. We report a 63-year-old woman with a 20-year history of ulcerative vulvo-vaginitis, initially diagnosed as benign mucous membrane (cicatricial) pemphigoid. This led to prolonged treatment with oral corticosteroids with minimal improvement in symptoms. Subsequent complications of long-term use of systemic corticosteroid ensued. A clinico-pathological diagnosis of severe erosive lichen planus was made on clinical findings and on non-specific biopsy changes of ulceration and inflammation. Treatment with topical clobetasol propionate 0.05% ointment twice daily led to dramatic improvement of ulceration, easing of discomfort and marked improvement in quality of life. Clinical examination revealed Wickham's striae on the labia majora supporting the diagnosis. Six years after commencement of topical clobetasol, white plaques were noticed on the labia majora, perineum and peri-anal region consistent with lichen sclerosus, confirmed by repeat vulval skin biopsy and on vulvectomy. This case highlights the challenge of diagnosis of extensive vulvo-vaginal ulceration and the necessity to re-examine a previous diagnosis if there is poor response to treatment.

  19. Lichens and atmospheric pollution

    Energy Technology Data Exchange (ETDEWEB)

    Tallis, J H

    1964-09-01

    The extreme sensitivity of lichens, particularly the larger ones, to industrialization has been recognized for many years. Most people attribute the absence of lichens from urban areas to the atmospheric pollution prevailing, and a few attribute it to climatic dryness, resulting from efficient drainage systems in towns. The two main components of air pollution are solid matter, or soot, and gaseous sulfur dioxide. The main effects of pollution appear to be: a direct reduction of light intensity by smoke haze, a deposit of soot on the plant surface, an acidification of the soil, and direct damage to plants. A body of evidence indicates that SO/sub 2/ may be the main harmful component for lichens. The distribution of lichens thus might be used to determine the limits within which atmospheric pollution is operating. 5 references.

  20. Lichens as bio indicators

    International Nuclear Information System (INIS)

    2003-01-01

    This publication discusses the use of lichens as biological indicators. Perennial growth, long life, efficient take-up of mineral nutrients from air and rain and small loss of nutrition are properties that make lichens suitable as biological indicators. In surveys and monitoring, species diversity and coverage by organisms that live as epiphytes on tree trunks have been the most commonly used parameters. A decline in the occurrence of this type of lichen is often related to the content of sulphur compounds in the air and it has been demonstrated that many species are sensitive to sulphur dioxide. It is also known that the growth of many types of lichens increases with a moderate increase in available nitrogen. In South Norway, pollution sensitive species such as Bryoria spp. have advanced strongly, which is probably due to less sulphur in the rain and a higher content of nutrition in the form of nitrate and ammonium

  1. Learning about Lichens.

    Science.gov (United States)

    McKenzie, Danny

    1982-01-01

    Provides background information and teaching suggestions for collecting and using lichens in the classroom and for conducting field investigations. Focuses on structure, reproduction, photosynthesis, and effects of air pollution. (DC)

  2. Oral Lichen Planus.

    Science.gov (United States)

    Ion, Daniela I; Setterfield, Jane F

    2016-02-01

    Lichen planus (LP) is a relatively common autoimmune T-cell-mediated disease of unknown aetiology affecting the mucous membranes, skin and nails. Its prevalence varies between 0.5 and 2.2% of the population in epidemiological studies with a peak incidence in the 30-60 years range and with a female predominance of 2:1. Mucosal lichen planus tends to follow a chronic course with acute exacerbations. Spontaneous remission of oral lichen planus (OLP) is uncommon, and indeed mucosal LP may become worse with time. In contrast, cutaneous lichen planus may follow a milder clinical course though some variants may be severe such as those affecting the palms and soles and the scalp and the genital tract in females (vulvovaginal gingival LP) where scarring leads to significant complications. It is important to identify those cases that may be drug induced or be associated with a contact allergic or irritant reaction (lichenoid reaction) or the rarer oral presentation of discoid lupus erythematosus. There is a very small risk of malignancy (approximately 1:200 patients/year) associated with oral lichen planus; thus patients should be informed that long term monitoring via their general dental practitioner is appropriate. This review will focus on the clinical presentation and management of oral lichen planus.

  3. Bullous lichen planus - a review.

    Science.gov (United States)

    Liakopoulou, Angeliki; Rallis, Efstathios

    2017-03-31

    Bullous lichen planus is a rare variant of lichen planus. It is characterized by vesicles or bullae, which usually develop in the context of pre-existing LP lesions. It is often misdiagnosed and should be differentiated from other subepidermal bullous diseases especially lichen planus pemphigoides. The diagnosis is based on clinical suspicion and is confirmed by histopathology and immunofluoresence. The clinical features of bullous lichen planus include typical lichen planus lesions, accompanied by the formation of bullae on the affected or perilesional skin. This is evident on histology, with alteration of the dermo-epidermal junction and intrabasal bullae as a consequence of extensive inflammation. The histologic features in conjunction with the negative immunofluoresence indicate that bullous lichen planus is a form of "hyper-reactive lichen planus" rather than a distinct entity. There is no standard treatment of bullous lichen planus. Topical and systemic corticosteroids, dapsone and acitretin have been described as effective choices.

  4. Oral Lichen Planus in Children

    OpenAIRE

    Mohan Das, Usha; JP, Beena

    2009-01-01

    Oral lichen planus which is one of the most common oral mucosal diseases in adults, it has been rarely described in children. There are very reports in the literature regarding oral lichen planus in children, here we report a case of intraoral lesions of lichen planus. Lichen planus should be considered in the differential diagnosis of hyperkeratotic or erosive lesions of the oral mucosa in children.

  5. Evolution: Welcome to Symbiont Prison

    NARCIS (Netherlands)

    Kiers, E.T.; West, S.A.

    2016-01-01

    Can egalitarian partnerships exist in nature? A new study demonstrates how protist hosts use and abuse their algal symbionts depending on their needs. While this relationship allows protists to survive in low nutrient conditions, it leaves little room for algal retaliation.

  6. Insect symbionts in food webs

    Czech Academy of Sciences Publication Activity Database

    McLean, A. H. C.; Parker, B. J.; Hrček, Jan; Henry, L. M.; Godfray, H. C. J.

    2016-01-01

    Roč. 371, č. 1702 (2016), article number 20150325 ISSN 0962-8436 Institutional support: RVO:60077344 Keywords : food web * symbiont * symbiosis Subject RIV: EE - Microbiology, Virology Impact factor: 5.846, year: 2016 http://rstb.royalsocietypublishing.org/content/371/1702/20150325

  7. Oral lichen planus

    Directory of Open Access Journals (Sweden)

    Šehalić Meliha

    2014-01-01

    Full Text Available 29 - year Lichen planus is a chronic, inflammatory, autoimmune skin disease, that is often manifested, except on the skin, in the oral cavity in a variety of clinical forms. The prevalence of the disease in the general population is about 1-2%. Etiopathogenesis is not still well understood. Histopathology, in addition to the basic methods, anamnesis and physical examination, is vital for proper diagnosis of oral lichen planus (OLP. Very diverse and loaded histological findings are common for all forms of oral lichen planus. We reported the case of oral lichen planus in a 49 years old male patient, who presented to the Dentistry clinic of Medical faculty of Priština with burning and itching symptoms and changes in the buccal mucosa. Histopathological analysis of biopsy tissue conformed clinical diagnosis of lichen planus. Due to the possibility for malignant transformation of lesions, the long-term follow-up of patients with this disease is of great importance.

  8. Fungal farmers or algal escorts: lichen adaptation from the algal perspective.

    Science.gov (United States)

    Piercey-Normore, Michele D; Deduke, Christopher

    2011-09-01

    Domestication of algae by lichen-forming fungi describes the symbiotic relationship between the photosynthetic (green alga or cyanobacterium; photobiont) and fungal (mycobiont) partnership in lichen associations (Goward 1992). The algal domestication implies that the mycobiont cultivates the alga as a monoculture within its thallus, analogous to a farmer cultivating a food crop. However, the initial photobiont 'selection' by the mycobiont may be predetermined by the habitat rather than by the farmer. When the mycobiont selects a photobiont from the available photobionts within a habitat, the mycobiont may influence photobiont growth and reproduction (Ahmadjian & Jacobs 1981) only after the interaction has been initiated. The theory of ecological guilds (Rikkinen et al. 2002) proposes that habitat limits the variety of photobionts available to the fungal partner. While some studies provide evidence to support the theory of ecological guilds in cyanobacterial lichens (Rikkinen et al. 2002), other studies propose models to explain variation in symbiont combinations in green algal lichens (Ohmura et al. 2006; Piercey-Normore 2006; Yahr et al. 2006) hypothesizing the existence of such guilds. In this issue of Molecular Ecology, Peksa & Škaloud (2011) test the theory of ecological guilds and suggest a relationship between algal habitat requirements and lichen adaptation in green algal lichens of the genus Lepraria. The environmental parameters examined in this study, exposure to rainfall, altitude and substratum type, are integral to lichen biology. Lichens have a poikilohydric nature, relying on the availability of atmospheric moisture for metabolic processes. Having no known active mechanism to preserve metabolic thallus moisture in times of drought, one would expect a strong influence of the environment on symbiont adaptation to specific habitats. Adaptation to changes in substrata and its properties would be expected with the intimate contact between crustose

  9. Specific Midgut Region Controlling the Symbiont Population in an Insect-Microbe Gut Symbiotic Association

    Science.gov (United States)

    Kim, Jiyeun Kate; Kim, Na Hyang; Jang, Ho Am; Kikuchi, Yoshitomo; Kim, Chan-Hee

    2013-01-01

    Many insects possess symbiotic bacteria that affect the biology of the host. The level of the symbiont population in the host is a pivotal factor that modulates the biological outcome of the symbiotic association. Hence, the symbiont population should be maintained at a proper level by the host's control mechanisms. Several mechanisms for controlling intracellular symbionts of insects have been reported, while mechanisms for controlling extracellular gut symbionts of insects are poorly understood. The bean bug Riptortus pedestris harbors a betaproteobacterial extracellular symbiont of the genus Burkholderia in the midgut symbiotic organ designated the M4 region. We found that the M4B region, which is directly connected to the M4 region, also harbors Burkholderia symbiont cells, but the symbionts therein are mostly dead. A series of experiments demonstrated that the M4B region exhibits antimicrobial activity, and the antimicrobial activity is specifically potent against the Burkholderia symbiont but not the cultured Burkholderia and other bacteria. The antimicrobial activity of the M4B region was detected in symbiotic host insects, reaching its highest point at the fifth instar, but not in aposymbiotic host insects, which suggests the possibility of symbiont-mediated induction of the antimicrobial activity. This antimicrobial activity was not associated with upregulation of antimicrobial peptides of the host. Based on these results, we propose that the M4B region is a specialized gut region of R. pedestris that plays a critical role in controlling the population of the Burkholderia gut symbiont. The molecular basis of the antimicrobial activity is of great interest and deserves future study. PMID:24038695

  10. Lichens as pollution indicators

    Energy Technology Data Exchange (ETDEWEB)

    Rose, F

    1970-01-01

    Although lichens are generally considered to be of little use to man, their sensitivity to air pollution makes them good biological indicators. The author describes how this feature can help to establish relative degrees of air pollution. He notes areas where lichens are reduced in number and vigor, and some in which they have disappeared altogether. He challenges the idea that dryness is responsible, since they have also disappeared from damp woodland areas. Experimental work supports the view that sulfur dioxide is the major factor rather than smoke, although there is no definitive proof. Lichen damage correlates best with mean winter levels of air pollution by SO/sub 2/. 16 references, 1 figure.

  11. Water relations, thallus structure and photosynthesis in Negev Desert lichens

    Science.gov (United States)

    Palmer, R. J. Jr; Friedmann, E. I.

    1990-01-01

    The role of lichen thallus structure in water relations and photosynthesis was studied in Ramalina maciformis (Del.) Bory and Teloschistes lacunosus (Rupr.) Sav. Water-vapour adsorption and photosynthesis are dependent upon thallus integrity and are significantly lower in crushed thalli. Cultured phycobiont (Trebouxia sp.) cells are capable of photosynthesis over the same relative humidity range (> 80% RH) as are intact lichens. Thus, water-vapour adsorption by the thallus and physiological adaptation of the phycobiont contribute to the ability of these lichens to photosynthesize in an arid environment. Despite differences in their anatomical structure and water-uptake characteristics, their CO2 incorporation is similar. The two lichens use liquid water differently and they occupy different niches.

  12. Oral lichen planus

    International Nuclear Information System (INIS)

    Rasool, S.; Katpar, S.; Ali, A.

    2007-01-01

    Lichen planus is a mucocutaneous dermatological disorder, with intraoral manifestation. Skin lesions prevail with oral mucosal lesions. Prevalence of lichen planus, as an oral pre-malignant lesion, is 1-2 % population. Lateral border, dorsal tongue, gingiva, hard palate and vermilion border are common sites and lesions appear as reticular, plaque-like and papular intraoral types. Skin presents with pururitic, polygonal papules. Atrophic and erosive are the known intraoral pre-malignant types. A case report is presented, which responded well to steroid therapy. (author)

  13. Fungal Diversity in Lichens: From Extremotolerance to Interactions with Algae

    Directory of Open Access Journals (Sweden)

    Lucia Muggia

    2018-05-01

    Full Text Available Lichen symbioses develop long-living thallus structures even in the harshest environments on Earth. These structures are also habitats for many other microscopic organisms, including other fungi, which vary in their specificity and interaction with the whole symbiotic system. This contribution reviews the recent progress regarding the understanding of the lichen-inhabiting fungi that are achieved by multiphasic approaches (culturing, microscopy, and sequencing. The lichen mycobiome comprises a more or less specific pool of species that can develop symptoms on their hosts, a generalist environmental pool, and a pool of transient species. Typically, the fungal classes Dothideomycetes, Eurotiomycetes, Leotiomycetes, Sordariomycetes, and Tremellomycetes predominate the associated fungal communities. While symptomatic lichenicolous fungi belong to lichen-forming lineages, many of the other fungi that are found have close relatives that are known from different ecological niches, including both plant and animal pathogens, and rock colonizers. A significant fraction of yet unnamed melanized (‘black’ fungi belong to the classes Chaethothyriomycetes and Dothideomycetes. These lineages tolerate the stressful conditions and harsh environments that affect their hosts, and therefore are interpreted as extremotolerant fungi. Some of these taxa can also form lichen-like associations with the algae of the lichen system when they are enforced to symbiosis by co-culturing assays.

  14. Physical contact and carbon transfer between a lichen-forming Trebouxia alga and a novel Alphaproteobacterium.

    Science.gov (United States)

    Kono, Mieko; Tanabe, Hideyuki; Ohmura, Yoshihito; Satta, Yoko; Terai, Yohey

    2017-05-01

    Recent progress in molecular techniques has begun to alter traditional recognition of lichens as symbiotic organisms comprised of a fungus and photosynthetic partners (green algae and/or cyanobacteria). Diverse organisms, especially various non-photosynthetic bacteria, are now indicated to be integral components of lichen symbiosis. Although lichen-associated bacteria are inferred to have functions that could support the symbiosis, little is known about their physical and nutritional interaction with fungi and algae. In the present study, we identified specific interaction between a lichen-forming alga and a novel bacterium. Trebouxia alga was isolated from a lichen, Usnea hakonensis, and kept as a strain for 8 years. Although no visible bacterial colonies were observed in this culture, high-throughput sequencing of DNA isolated from the culture revealed that the strain is composed of a Trebouxia alga and an Alphaproteobacterium species. In situ hybridization showed that bacterial cells were localized on the surface of the algal cells. Physiological assays revealed that the bacterium was able to use ribitol, glucose and mannitol, all of which are known to exist abundantly in lichens. It was resistant to three antibiotics. Bacteria closely related to this species were also identified in lichen specimens, indicating that U. hakonensis may commonly associate with this group of bacteria. These features of the novel bacterium suggest that it may be involved in carbon cycling of U. hakonensis as a member of lichen symbiosis and less likely to have become associated with the alga after isolation from a lichen.

  15. Coexistence of nail lichen planus and lichen planus pigmentosus.

    Science.gov (United States)

    Lemes, Luciana Rodino; Verde, Renata Brandão Villa; Durães, Sandra Maria Barbosa; Araripe, Adolpho de Alencar; Pantaleão, Luciana

    2016-01-01

    We describe a fifty-six-year old, Afro-descendent female patient showing dystrophy of her twenty nails and hyperchromic, asymptomatic macule on her face. Histopathological examination of the macule showed vacuolization of the basal layer, melanophages in the superficial dermis and lymphoplasmocytic inflammatory infiltrate. Nail biopsy revealed orthokeratotic hyperkeratosis and lichenoid inflammatory infiltrate. Lichen planus pigmentosus is an uncommon variety of lichen planus. It is characterized by typical hyperpigmented macules on the face and neck. Nail changes might be present in 10% of lichen planus cases, but no associations with lichen planus pigmentosus have been described. We report a case of lichen planus in twenty nails associated with lichen planus pigmentosus on the patient's face.

  16. Lichen compounds restrain lichen feeding by bank voles (Myodes glareolus).

    Science.gov (United States)

    Nybakken, Line; Helmersen, Anne-Marit; Gauslaa, Yngvar; Selås, Vidar

    2010-03-01

    Some lichen compounds are known to deter feeding by invertebrate herbivores. We attempted to quantify the deterring efficiency of lichen compounds against a generalist vertebrate, the bank vole (Myodes glareolus). In two separate experiments, caged bank voles had the choice to feed on lichens with natural or reduced concentrations of secondary compounds. We rinsed air-dry intact lichens in 100% acetone to remove extracellular compounds non-destructively. In the first experiment, pairs of control and rinsed lichen thalli were hydrated and offered to the bank voles. Because the lichens desiccated fast, we ran a second experiment with pairs of ground control and compound-deficient thalli, each mixed with water to porridge. Eight and six lichen species were tested in the first and second experiment, respectively. In the first, bank voles preferred compound-deficient thalli of Cladonia stellaris and Lobaria pulmonaria, but did not discriminate between the other thallus pairs. This was likely a result of deterring levels of usnic and stictic acid in the control thalli. When lichens were served as porridge, significant preference was found for acetone-rinsed pieces of Cladonia arbuscula, C. rangiferina, Platismatia glauca, and Evernia prunastri. The increased preference was caused mainly by lower consumption of control thalli. Grinding and mixing of thallus structures prevented bank voles from selecting thallus parts with lower concentration of secondary compounds and/or strengthened their deterring capacity. We conclude that some lichen secondary compounds deter feeding by bank voles.

  17. Prevalence of Candida Species in Erosive Oral Lichen Planus

    Directory of Open Access Journals (Sweden)

    Masoumeh Mehdipour

    2010-03-01

    Full Text Available Background and aims. The clinical management of oral lichen planus poses considerable difficulties to the clinician. In recent years, researchers have focused on the presence of pathogenic microorganisms such as Candida albicans in the patients with refractory lichen planus. The aim of the present study was to investigate the prevalence of candida species in the erosive oral lichen planus lesions. Materials and methods. Twenty-one patients with erosive oral lichen planus and twenty-one healthy individuals aged 18-60 were randomly selected; samples were taken from the tongue, saliva and buccal mucosa with swab friction. Theses samples were sent to the laboratory for determining the presence of candida species in cultures and direct examination method. Results. No significant difference was found between healthy individuals and patients with erosive lichen planus regarding presence of candida species. The type of candida in the evaluated samples was Candida albicans in both healthy and patient groups. Conclusion. According to the results, candida was not confirmed as an etiologic factor for erosive lichen planus lesions.

  18. Speciation of Hg in lichens

    International Nuclear Information System (INIS)

    Jereb, Vesna; Horvat, Milena

    2002-01-01

    Lichens have long been regarded as a suitable tool for monitoring the relative levels of atmospheric pollutants. Lichens have neither roots, a waxy cuticle nor stomata: hence, for mineral nutrition they are largely dependent on wet and dry deposition from the atmosphere. Moreover, lichens are perennial and can accumulate elements over long periods of time. Therefore, concentrations of elements in lichens represent the average levels of elements in the atmosphere for a long period of time. The epiphytic lichen Hypogymnia physodes is a good bioindicator of air pollution with total mercury (THg). In addition, it contains small amounts of methylmercury (MeHg + ). The first aim of our work was to test analytical techniques for determination of MeHg in lichens taken from different locations in Idrija and reference locations

  19. Biomonitoring with lichens on twigs

    DEFF Research Database (Denmark)

    Vilsholm, René Larsen; Wolseley, Pat; Søchting, Ulrik

    2009-01-01

    Two surveys of the lichen and bryophyte flora growing on oak twigs from a Welsh and a Danish locality were compared with additional data on bark pH and % nitrogen in thalli of Hypogymnia physodes. Despite differences in climate and lichen flora, both sites showed a shift in the lichen communities...... showing a loss of nitrophobes in all sites and the appearance of nitrophiles in pasture sites in 2003. This study demonstrates that lichens on twigs can be used as an early warning system to detect a response to changes in land management and nitrogen deposition....

  20. Nutrient scavenging activity and antagonistic factors of non-photobiont lichen-associated bacteria: a review.

    Science.gov (United States)

    Sigurbjörnsdóttir, M Auður; Andrésson, Ólafur S; Vilhelmsson, Oddur

    2016-04-01

    Lichens are defined as the specific symbiotic structure comprising a fungus and a green alga and/or cyanobacterium. Up until recently, non-photobiont endothallic bacteria, while known to be present in large numbers, have generally been dismissed as functionally irrelevant cohabitants of the lichen thallus, or even environmental contaminants. Recent analyses of lichen metagenomes and innovative co-culture experiments have uncovered a functionally complex community that appears to contribute to a healthy lichen thallus in several ways. Lichen-associated bacteriomes are typically dominated by several lineages of Proteobacteria, some of which may be specific for lichen species. Recent work has implicated members of these lineages in several important ecophysiological roles. These include nutrient scavenging, including mobilization of iron and phosphate, nitrogen fixation, cellulase, xylanase and amylase activities, and oxidation of recalcitrant compounds, e.g. aromatics and aliphatics. Production of volatile organic compounds, conferring antibacterial and antifungal activity, has also been demonstrated for several lichen-associated isolates. In the present paper we review the nature of non-phototrophic endolichenic bacteria associated with lichens, and give insight into the current state of knowledge on their importance the lichen symbiotic association.

  1. Air pollution and lichens

    Energy Technology Data Exchange (ETDEWEB)

    Ferry, B W; Baddeley, M S; Hawksworth, D L [eds.

    1973-01-01

    This volume reflects the particular concern of many biologists for the effects of air pollution and illustrates the special values of lichens as plants suitable for such studies. It brings together contributions from many experts in this field and includes much previously unpublished data, as well as up-to-date review chapters. Emphasis is placed on the logical progression from field observational studies to critical laboratory investigations aimed at elucidating the modes of action of various air pollutants on the living tissues of lichens. The action of such pollutants on vascular plants is also discussed. It is the editors' intention that the book be both a reference volume and an encouragement for further wor

  2. Air pollution and lichens

    Energy Technology Data Exchange (ETDEWEB)

    Ferry, B W; Baddeley, M S; Hawksworth, D L [eds.

    1973-01-01

    This volume reflects the concern of biologists for the effects of air pollution and illustrates the special values of lichens as plants suitable for such studies. Emphasis is placed on the logical progression from field observational studies to laboratory investigations aimed at elucidating the modes of action of various pollutants. The actions of pollutants on vascular plants is also discussed. Separate analytics are included for 17 chapters.

  3. Lichenized Ascomycetes (Lichenes of the Choszczno Lake District

    Directory of Open Access Journals (Sweden)

    Ludwik Lipnicki

    2014-08-01

    Full Text Available The paper includes the list of 184 species of Lichens stated in the area of Choszczno Lake District. It gives the ecological conditions of their occurrence and the number of sites. Theendangered lichens growing in the forest-bereft regions which were under the strong influence of factors included by intensive agriculture were presented.

  4. Zosteriform Lichen Planus: case report of a rare variant of Lichen Planus

    OpenAIRE

    Kanthilatha Pai; Sathish Pai

    2013-01-01

    Since its original description by Devergie in 1854, several cases of linear lichen planus have been described in the literature, but there have been notably few cases of the more rare zosteriform lichen planus. Zosteriform lichen planus needs to be differentiated from linear lichen planus and other linear dermatoses. We present a case of Zosteriform Lichen planus for its rarity and briefly review literature.

  5. Facultative symbiont infections affect aphid reproduction.

    Science.gov (United States)

    Simon, Jean-Christophe; Boutin, Sébastien; Tsuchida, Tsutomu; Koga, Ryuichi; Le Gallic, Jean-François; Frantz, Adrien; Outreman, Yannick; Fukatsu, Takema

    2011-01-01

    Some bacterial symbionts alter their hosts reproduction through various mechanisms that enhance their transmission in the host population. In addition to its obligatory symbiont Buchnera aphidicola, the pea aphid Acyrthosiphon pisum harbors several facultative symbionts influencing several aspects of host ecology. Aphids reproduce by cyclical parthenogenesis whereby clonal and sexual reproduction alternate within the annual life cycle. Many species, including the pea aphid, also show variation in their reproductive mode at the population level, with some lineages reproducing by cyclical parthenogenesis and others by permanent parthenogenesis. While the role of facultative symbionts has been well studied during the parthenogenetic phase of their aphid hosts, very little is known on their possible influence during the sexual phase. Here we investigated whether facultative symbionts modulate the capacity to produce sexual forms in various genetic backgrounds of the pea aphid with controlled symbiont composition and also in different aphid genotypes from natural populations with previously characterized infection status and reproductive mode. We found that most facultative symbionts exhibited detrimental effects on their hosts fitness under sex-inducing conditions in comparison with the reference lines. We also showed that the loss of sexual phase in permanently parthenogenetic lineages of A. pisum was not explained by facultative symbionts. Finally, we demonstrated that Spiroplasma infection annihilated the production of males in the host progeny by inducing a male-killing phenotype, an unexpected result for organisms such as aphids that reproduce primarily through clonal reproduction.

  6. Facultative symbiont infections affect aphid reproduction.

    Directory of Open Access Journals (Sweden)

    Jean-Christophe Simon

    Full Text Available Some bacterial symbionts alter their hosts reproduction through various mechanisms that enhance their transmission in the host population. In addition to its obligatory symbiont Buchnera aphidicola, the pea aphid Acyrthosiphon pisum harbors several facultative symbionts influencing several aspects of host ecology. Aphids reproduce by cyclical parthenogenesis whereby clonal and sexual reproduction alternate within the annual life cycle. Many species, including the pea aphid, also show variation in their reproductive mode at the population level, with some lineages reproducing by cyclical parthenogenesis and others by permanent parthenogenesis. While the role of facultative symbionts has been well studied during the parthenogenetic phase of their aphid hosts, very little is known on their possible influence during the sexual phase. Here we investigated whether facultative symbionts modulate the capacity to produce sexual forms in various genetic backgrounds of the pea aphid with controlled symbiont composition and also in different aphid genotypes from natural populations with previously characterized infection status and reproductive mode. We found that most facultative symbionts exhibited detrimental effects on their hosts fitness under sex-inducing conditions in comparison with the reference lines. We also showed that the loss of sexual phase in permanently parthenogenetic lineages of A. pisum was not explained by facultative symbionts. Finally, we demonstrated that Spiroplasma infection annihilated the production of males in the host progeny by inducing a male-killing phenotype, an unexpected result for organisms such as aphids that reproduce primarily through clonal reproduction.

  7. Restriction Fragment Length Polymorphism Analysis Reveals High Levels of Genetic Divergence Among the Light Organ Symbionts of Flashlight Fish.

    Science.gov (United States)

    Wolfe, C J; Haygood, M G

    1991-08-01

    Restriction fragment length polymorphisms within the lux and 16S ribosomal RNA gene regions were used to compare unculturable bacterial light organ symbionts of several anomalopid fish species. The method of Nei and Li (1979) was used to calculate phylogenetic distance from the patterns of restriction fragment lengths of the luxA and 16S rRNA regions. Phylogenetic trees constructed from each distance matrix (luxA and 16S rDNA data) have similar branching orders. The levels of divergence among the symbionts, relative to other culturable luminous bacteria, suggests that the symbionts differ at the level of species among host fish genera. Symbiont relatedness and host geographic location do not seem to be correlated, and the symbionts do not appear to be strains of common, free-living, luminous bacteria. In addition, the small number of hybridizing fragments within the 16S rRNA region of the symbionts, compared with that of the free-living species, suggests a decrease in copy number of rRNA operons relative to free-living species. At this level of investigation, the symbiont phylogeny is consistent with the proposed phylogeny of the host fish family and suggests that each symbiont strain coevolved with its host fish species.

  8. LICHEN STRIATUS – CASE REPORTS

    OpenAIRE

    Caius Solovan; Cristina Birsan; Anca E. Chiriac; Liliana Foia; Anca Chiriac; Piotr Brzeziński

    2013-01-01

    Lichen striatus is an acquired linear inflammatory dermatosis, not frequently reported, with a peculiar clinical aspect, most often described in adults, with a poor response to treatment. We described 4 cases of lichen striatus diagnosed over an 8-month period of time.

  9. LICHEN STRIATUS – CASE REPORTS

    Directory of Open Access Journals (Sweden)

    Caius Solovan

    2013-07-01

    Full Text Available Lichen striatus is an acquired linear inflammatory dermatosis, not frequently reported, with a peculiar clinical aspect, most often described in adults, with a poor response to treatment. We described 4 cases of lichen striatus diagnosed over an 8-month period of time.

  10. Lichen species preference by reindeer

    Energy Technology Data Exchange (ETDEWEB)

    Holleman, D F; Luick, J R

    1977-08-01

    The preference by reindeer for five species of lichens commonly found on Central Alaska rangelands was tested under controlled laboratory conditions. Results indicate that reindeer are strongly selective species in their lichen grazing habits. The five tested species ranged as follows in order of decreasing acceptibility: Caldonia alpestris, C. rangiferina, Stereocaulon paschale, Cetraria richardsonii, and Peltigera aphthosa.

  11. Lichens as bioindicators of air quality

    Science.gov (United States)

    K. Stolte; D. Mangis; R. Doty; K. Tonnessen; Laurie S.  Huckaby

    1993-01-01

    This report is the result of a workshop held in Denver, Colorado on April 9-11, 1991. It summarizes the current literature and techniques for using lichens to monitor air quality. Experts in lichenology and ecology contributed information on lichen floristics, characterization of monitoring sites, lichen species and communities, identifying lichen species...

  12. A clinicopathological study of cutaneous lichen planus

    OpenAIRE

    Parihar, Asmita; Sharma, Sonal; Bhattacharya, Sambit Nath; Singh, Usha Rani

    2015-01-01

    Background: Lichen planus is an idiopathic subacute or chronic inflammatory disease of the skin, mucous membranes and nails. We studied the clinicopathological profile of lichen planus in Indian population. Methods: A total of 145 cases of histologically diagnosed lichen planus samples were included. Clinical features like age, sex, type of lichen planus, location were recorded in the case record form. Histological features of lichen planus were studied. Results: Out of 145 cases, major...

  13. Crescimento do fungo simbionte de formigas cortadeiras do gênero Acromyrmex em meios de cultura com diferentes extratos Growth of symbiont fungi of cutter ants of the genus Acromyrmex in means of culture with different extracts

    Directory of Open Access Journals (Sweden)

    Regina da Silva Borba

    2006-06-01

    plants have been accomplished to evaluate the effect on the development of the mushroom symbiont. The objective of this work was to evaluate the influence of added culture means of different extracts on the growth of the L. gongylophorus mushroom. Where mushrooms of the species Acromyrmex ambiguus, Acromyrmex crassispinus, Acromyrmex heyeri and Acromyrmex lundi were inoculated in the means Nutritious Ágar and BDA, both added of molasses and extracts of Lolium multiflorum Lam., Typha angustifolia L. and ant (Atta sexdens piriventris. The Pagnocca medium was used as pattern. The plates were maintained in cameras acclimatized to the temperature of 25 + 1°C and 24 hours of darkness, for a period of 49 days. The fungal growth was evaluated with base in the diameter of the colony, which was accomplished with weekly intervals, totalizing seven evaluations. Also the dry weight was evaluated from the mushroom to the 53 days. The results showed that the mushroom cultivated by different species of ants has differentiated growth in culture means with different extracts.

  14. Understanding regulation of the host-mediated gut symbiont population and the symbiont-mediated host immunity in the Riptortus-Burkholderia symbiosis system.

    Science.gov (United States)

    Kim, Jiyeun Kate; Lee, Jun Beom; Jang, Ho Am; Han, Yeon Soo; Fukatsu, Takema; Lee, Bok Luel

    2016-11-01

    Valuable insect models have tremendously contributed to our understanding of innate immunity and symbiosis. Bean bug, Riptortus pedestris, is a useful insect symbiosis model due to harboring cultivable monospecific gut symbiont, genus Burkholderia. Bean bug is a hemimetabolous insect whose immunity is not well-understood. However, we recently identified three major antimicrobial peptides of Riptortus and examined the relationship between gut symbiosis and host immunity. We found that the presence of Burkholderia gut symbiont positively affects Riptortus immunity. From studying host regulation mechanisms of symbiont population, we revealed that the symbiotic Burkholderia cells are much more susceptible to Riptortus immune responses than the cultured cells. We further elucidated that the immune-susceptibility of the Burkholderia gut symbionts is due to the drastic change of bacterial cell envelope. Finally, we show that the immune-susceptible Burkholderia symbionts are able to prosper in host owing to the suppression of immune responses of the symbiotic midgut. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Erosive lichen planus: a therapeutic challenge.

    Science.gov (United States)

    Romero, Williams; Giesen, Laura; Navajas-Galimany, Lucas; Gonzalez, Sergio

    2016-01-01

    Erosive lichen planus is an uncommon variant of lichen planus. Chronic erosions of the soles, accompanied by intense and disabling pain, are some of its most characteristic manifestations. We present the case of a woman who developed oral and plantar erosive lichen planus associated with lichen planus pigmentosus and ungueal lichen planus that were diagnosed after several years. The patient failed to respond to multiple therapies requiring longstanding medication but remained refractory. Knowledge of the treatment options for erosive lichen planus is insufficient. Further research is required to clarify their effectiveness, ideally adopting an evidence-based methodology.

  16. Lichen techniques of pollution assessment

    Energy Technology Data Exchange (ETDEWEB)

    O' Hare, G

    1973-01-01

    Available techniques for determining air pollution by sulfur dioxide using lichens are described. An application of these methods - species distributions, zone mapping and analyses of total sulfur content - in the west central Scotland area, is briefly reported.

  17. Oral candidosis in lichen planus

    DEFF Research Database (Denmark)

    Kragelund, Camilla; Kieffer-Kristensen, L; Reibel, J

    2012-01-01

    OBJECTIVES: Candida albicans is the most common fungal pathogen in humans, but other Candida species cause candidosis. Candida species display significant differences in their susceptibility to antimycotic drugs. Patients with symptomatic or erythematous oral lichen planus (OLP) commonly have...

  18. Oral lichen planus: An overview

    Directory of Open Access Journals (Sweden)

    R Jayasri Krupaa

    2015-01-01

    Full Text Available Lichen planus is an immunologically mediated mucocutaneous disease that is triggered by varied etiological agents. The oral lichenoid reaction is considered a variant of the disease that needs to be clearly diagnosed as a separate entity from oral lichen planus and treated. They follow a strict cause-effector relationship, protocols that suggest the differentiation. Lichen planus has varied clinical forms in the oral mucosa and cutaneously that has different prognosis. This condition also arises in association with various other systemic conditions such as hypertension, diabetes mellitus. There have been cases reported in the esophagus, larynx, scalp, nail, cutaneous areas, especially arms and wrists, trunk. There is reported malignant transformation that essentiates careful examination, treatment protocol and regular follow-up sessions. This article throws light on the disease condition of oral lichen planus and oral lichenoid reaction that is essential for the differentiation and treatment.

  19. Oral lichen planus: An overview

    Science.gov (United States)

    Krupaa, R. Jayasri; Sankari, S. Leena; Masthan, K. M. K.; Rajesh, E.

    2015-01-01

    Lichen planus is an immunologically mediated mucocutaneous disease that is triggered by varied etiological agents. The oral lichenoid reaction is considered a variant of the disease that needs to be clearly diagnosed as a separate entity from oral lichen planus and treated. They follow a strict cause-effector relationship, protocols that suggest the differentiation. Lichen planus has varied clinical forms in the oral mucosa and cutaneously that has different prognosis. This condition also arises in association with various other systemic conditions such as hypertension, diabetes mellitus. There have been cases reported in the esophagus, larynx, scalp, nail, cutaneous areas, especially arms and wrists, trunk. There is reported malignant transformation that essentiates careful examination, treatment protocol and regular follow-up sessions. This article throws light on the disease condition of oral lichen planus and oral lichenoid reaction that is essential for the differentiation and treatment. PMID:26015696

  20. Molecular sizes of lichen ice nucleation sites determined by gamma radiation inactivation analysis

    International Nuclear Information System (INIS)

    Kieft, T.L.; Ruscetti, T.

    1992-01-01

    It has previously been shown that some species of lichen fungi contain proteinaceous ice nuclei which are active at temperatures as warm as −2 °C. This experiment was undertaken to determine the molecular sizes of ice nuclei in the lichen fungus Rhizoplaca chrysoleuca and to compare them to bacterial ice nuclei from Pseudomonas syringae. Gamma radiation inactivation analysis was used to determine molecular weights. Radiation inactivation analysis is based on target theory, which states that the likelihood of a molecule being inactivated by gamma rays increases as its size increases. Three different sources of ice nuclei from the lichen R. chrysoleuca were tested: field-collected lichens, extract of lichen fungus, and a pure culture of the fungus R. chrysoleuca. P. syringae strain Cit7 was used as a source of bacterial ice nuclei. Samples were lyophilized, irradiated with gamma doses ranging from 0 to 10.4 Mrads, and then tested for ice nucleation activity using a droplet-freezing assay. Data for all four types of samples were in rough agreement; sizes of nucleation sites increased logarithmically with increasing temperatures of ice nucleation activity. Molecular weights of nucleation sites active between −3 and −4 °C from the bacteria and from the field-collected lichens were approximately 1.0 × 10 6 Da. Nuclei from the lichen fungus and in the lichen extract appeared to be slightly smaller but followed the same log-normal pattern with temperature of ice nucleation activity. The data for both the bacterial and lichen ice nuclei are in agreement with ice nucleation theory which states that the size of ice nucleation sites increases logarithmically as the temperature of nucleation increases linearly. This suggests that although some differences exist between bacterial and lichen ice nucleation sites, their molecular sizes are quite similar

  1. Candidatus Sodalis melophagi sp. nov.: phylogenetically independent comparative model to the tsetse fly symbiont Sodalis glossinidius.

    Directory of Open Access Journals (Sweden)

    Tomáš Chrudimský

    Full Text Available Bacteria of the genus Sodalis live in symbiosis with various groups of insects. The best known member of this group, a secondary symbiont of tsetse flies Sodalis glossinidius, has become one of the most important models in investigating establishment and evolution of insect-bacteria symbiosis. It represents a bacterium in the early/intermediate state of the transition towards symbiosis, which allows for exploring such interesting topics as: usage of secretory systems for entering the host cell, tempo of the genome modification, and metabolic interaction with a coexisting primary symbiont. In this study, we describe a new Sodalis species which could provide a useful comparative model to the tsetse symbiont. It lives in association with Melophagus ovinus, an insect related to tsetse flies, and resembles S. glossinidius in several important traits. Similar to S. glossinidius, it cohabits the host with another symbiotic bacterium, the bacteriome-harbored primary symbiont of the genus Arsenophonus. As a typical secondary symbiont, Candidatus Sodalis melophagi infects various host tissues, including bacteriome. We provide basic morphological and molecular characteristics of the symbiont and show that these traits also correspond to the early/intermediate state of the evolution towards symbiosis. Particularly, we demonstrate the ability of the bacterium to live in insect cell culture as well as in cell-free medium. We also provide basic characteristics of type three secretion system and using three reference sequences (16 S rDNA, groEL and spaPQR region we show that the bacterium branched within the genus Sodalis, but originated independently of the two previously described symbionts of hippoboscoids. We propose the name Candidatus Sodalis melophagi for this new bacterium.

  2. Candidatus Sodalis melophagi sp. nov.: phylogenetically independent comparative model to the tsetse fly symbiont Sodalis glossinidius.

    Science.gov (United States)

    Chrudimský, Tomáš; Husník, Filip; Nováková, Eva; Hypša, Václav

    2012-01-01

    Bacteria of the genus Sodalis live in symbiosis with various groups of insects. The best known member of this group, a secondary symbiont of tsetse flies Sodalis glossinidius, has become one of the most important models in investigating establishment and evolution of insect-bacteria symbiosis. It represents a bacterium in the early/intermediate state of the transition towards symbiosis, which allows for exploring such interesting topics as: usage of secretory systems for entering the host cell, tempo of the genome modification, and metabolic interaction with a coexisting primary symbiont. In this study, we describe a new Sodalis species which could provide a useful comparative model to the tsetse symbiont. It lives in association with Melophagus ovinus, an insect related to tsetse flies, and resembles S. glossinidius in several important traits. Similar to S. glossinidius, it cohabits the host with another symbiotic bacterium, the bacteriome-harbored primary symbiont of the genus Arsenophonus. As a typical secondary symbiont, Candidatus Sodalis melophagi infects various host tissues, including bacteriome. We provide basic morphological and molecular characteristics of the symbiont and show that these traits also correspond to the early/intermediate state of the evolution towards symbiosis. Particularly, we demonstrate the ability of the bacterium to live in insect cell culture as well as in cell-free medium. We also provide basic characteristics of type three secretion system and using three reference sequences (16 S rDNA, groEL and spaPQR region) we show that the bacterium branched within the genus Sodalis, but originated independently of the two previously described symbionts of hippoboscoids. We propose the name Candidatus Sodalis melophagi for this new bacterium.

  3. Spallation symbiont and thorium breeding

    International Nuclear Information System (INIS)

    Furukawa, Kazuo

    1991-01-01

    The medium term world energy and environment countermeasures for 2020-2070 are not yet clearly established. The forecast of energy situation hereafter, its problems and the measures for solution are considered. World trend is removing borders, and the north-south problems are increasing the importance. The rational and clear idea with the support of concrete technology is required. The demand of energy will increase enormously at the annual rate of 2.3%. The world energy situation was forecast considering the increase of population, and it will be 115 TW at the end of the next century. The present status, problems and the countermeasures in nuclear fission energy technology are explained. The countermeasures should be based on three principles, namely Th-U-233 cycle, the utilization of molten fluoride fuel medium and the separation of molten salt breeders and molten salt reactors. Accelerator molten salt breeders, small molten salt reactors, the nuclear fuel cycle and the annihilation process for radioactive wastes are reported. The perspective that the nuclear energy system, in which the reactor safety, the measures to wastes and others are improved by the spallation-fission symbiont using thorium molten salt as the working medium, can be constructed is shown. (K.I.)

  4. Ammonium and nitrate tolerance in lichens

    Energy Technology Data Exchange (ETDEWEB)

    Hauck, Markus, E-mail: mhauck@gwdg.d [Department of Plant Ecology, Albrecht von Haller Institute of Plant Sciences, University of Goettingen, Untere Karspuele 2, 37073 Goettingen (Germany)

    2010-05-15

    Since lichens lack roots and take up water, solutes and gases over the entire thallus surface, these organisms respond more sensitively to changes in atmospheric purity than vascular plants. After centuries where effects of sulphur dioxide and acidity were in the focus of research on atmospheric chemistry and lichens, recently the globally increased levels of ammonia and nitrate increasingly affect lichen vegetation and gave rise to intense research on the tolerance of lichens to nitrogen pollution. The present paper discusses the main findings on the uptake of ammonia and nitrate in the lichen symbiosis and to the tolerance of lichens to eutrophication. Ammonia and nitrate are both efficiently taken up under ambient conditions. The tolerance to high nitrogen levels depends, among others, on the capability of the photobiont to provide sufficient amounts of carbon skeletons for ammonia assimilation. Lowly productive lichens are apparently predisposed to be sensitive to excess nitrogen. - Eutrophication has become a global threat for lichen diversity.

  5. Italian balustrade at Cliveden hosts Italian lichens?

    Czech Academy of Sciences Publication Activity Database

    Powell, M.; Vondrák, Jan

    2012-01-01

    Roč. 2012, č. 110 (2012), s. 11-14 ISSN 0300-4562 Institutional research plan: CEZ:AV0Z60050516 Institutional support: RVO:67985939 Keywords : diaspore transport * lichen colonization * Mediterranean lichen s Subject RIV: EF - Botanics

  6. EPR Spectroscopy in Environmental Lichen-Indication

    Science.gov (United States)

    Bondarenko, P. V.; Nguyet, Le Thi Bich; Zhuravleva, S. E.; Trukhan, E. M.

    2017-09-01

    The paramagnetic properties of lichens were investigated using EPR spectroscopy and Xanthoria parietina (L.) Th. Fr. as a case study. It was found that the concentration of paramagnetic centers in lichen thalli increased as the air-pollution level increased. Possible formation mechanisms of the paramagnetic centers in lichens were discussed. The efficiency of using EPR spectroscopy to study lichens as environmental quality indicators was demonstrated.

  7. A Case of Childhood Lichen Aureus

    OpenAIRE

    Kim, Min Ji; Kim, Byung Yoon; Park, Kyung Chan; Youn, Sang Woong

    2009-01-01

    Lichen aureus is a rare type of chronic pigmented purpuric dermatosis. The eruptions consist of discrete or confluent golden to brownish lichenoid macules and papules, and are usually asymptomatic. Lichen aureus commonly occurs in young adults, but less frequently in children. We report the first case of multiple lichen aureus occurring in a Korean child.

  8. Lichen Sclerosus et Atrophicus with Cutaneous Distribution Simulating Lichen Planus

    Directory of Open Access Journals (Sweden)

    M. Gómez Vázquez

    2010-04-01

    Full Text Available Lichen sclerosus (LS et atrophicus is a disease of unknown etiology, although hereditary, endocrine, and autoimmune factors are known to be involved. While the anal and genital regions are predominantly affected, only 2.5% of patients present with extragenital lesions, particularly of the trunk, neck, and upper limbs. The possible relationship between lichen sclerosus et atrophicus and both lichen planus (LP and localized scleroderma (morphea has not been clearly established, although in a number of cases, several of these conditions have been found simultaneously. We report the case of a 31-year-old woman with LS lesions affecting the neck, upper back, wrist and dorsum of the feet. The unusual character of this presentation is pointed out, along with its clinical similarity to LP.

  9. Xanthones of Lichen Source: A 2016 Update.

    Science.gov (United States)

    Le Pogam, Pierre; Boustie, Joël

    2016-03-02

    An update of xanthones encountered in lichens is proposed as more than 20 new xanthones have been described since the publication of the compendium of lichen metabolites by Huneck and Yoshimura in 1996. The last decades witnessed major advances regarding the elucidation of biosynthetic schemes leading to these fascinating compounds, accounting for the unique substitution patterns of a very vast majority of lichen xanthones. Besides a comprehensive analysis of the structures of xanthones described in lichens, their bioactivities and the emerging analytical strategies used to pinpoint them within lichens are presented here together with physico-chemical properties (including NMR data) as reported since 1996.

  10. On the dual nature of lichen-induced rock surface weathering in contrasting micro-environments.

    Science.gov (United States)

    Marques, Joana; Gonçalves, João; Oliveira, Cláudia; Favero-Longo, Sergio E; Paz-Bermúdez, Graciela; Almeida, Rubim; Prieto, Beatriz

    2016-10-01

    Contradictory evidence from biogeomorphological studies has increased the debate on the extent of lichen contribution to differential rock surface weathering in both natural and cultural settings. This study, undertaken in Côa Valley Archaeological Park, aimed at evaluating the effect of rock surface orientation on the weathering ability of dominant lichens. Hyphal penetration and oxalate formation at the lichen-rock interface were evaluated as proxies of physical and chemical weathering, respectively. A new protocol of pixel-based supervised image classification for the analysis of periodic acid-Schiff stained cross-sections of colonized schist revealed that hyphal spread of individual species was not influenced by surface orientation. However, hyphal spread was significantly higher in species dominant on northwest facing surfaces. An apparently opposite effect was noticed in terms of calcium oxalate accumulation at the lichen-rock interface; it was detected by Raman spectroscopy and complementary X-ray microdiffraction on southeast facing surfaces only. These results suggest that lichen-induced physical weathering may be most severe on northwest facing surfaces by means of an indirect effect of surface orientation on species abundance, and thus dependent on the species, whereas lichen-induced chemical weathering is apparently higher on southeast facing surfaces and dependent on micro-environmental conditions, giving only weak support to the hypothesis that lichens are responsible for the currently observed pattern of rock-art distribution in Côa Valley. Assumptions about the drivers of open-air rock-art distribution patterns elsewhere should also consider the micro-environmental controls of lichen-induced weathering, to avoid biased measures of lichen contribution to rock-art deterioration. © 2016 by the Ecological Society of America.

  11. Biological activities of undescribed North American lichen species.

    Science.gov (United States)

    Yeash, Erik A; Letwin, Lyndon; Malek, Lada; Suntres, Zacharias; Knudsen, Kerry; Christopher, Lew P

    2017-11-01

    Lichens provide a large array of compounds with the potential for pharmaceutical development. In the present study, extracts from three previously undescribed North American lichen species were examined for antioxidant, antibacterial and anticancer activities. The results from this study demonstrated the following: (i) Acarospora socialis ethanol extract exhibited significant DPPH antioxidant scavenging activities, which were concentration dependent; (ii) acetone and ethyl acetate extracts of Xanthoparmelia mexicana inhibited Gram-positive bacteria but had no effect on Gram-negative bacteria; X. mexicana acetone extract yielded a minimum inhibitory concentration (MIC) of 20.9 µg mL -1 against Staphylococcus aureus, and 41.9 µg mL -1 against Enterococcus faecalis; (iii) acetone extract of Lobothallia alphoplaca inhibited growth of cultured breast cancer MCF-7 cells with an effective concentration (EC 50 ) of 87 µg mL -1 ; the MCF-7 cell cycle appears arrested in the G2 phase, whereas the DNA synthesis cell cycle (S) may be inhibited. New lichen species that possess strong biological activities have been identified. These lichens comprise secondary metabolites that possess antioxidant, antibacterial and anticancer properties. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  12. Lichen microalgae are sensitive to environmental concentrations of atrazine.

    Science.gov (United States)

    Traba, Helena Moreno; Domínguez-Morueco, Noelia; Barreno, Eva; Catalá, Myriam

    2017-04-03

    The identification of new organisms for environmental toxicology bioassays is currently a priority, since these tools are strongly limited by the ecological relevance of taxa used to study global change. Lichens are sensitive bioindicators of air quality and their microalgae are an untapped source for new low-cost miniaturized bioassays with ecological importance. In order to increase the availability of a wider range of taxa for bioassays, the sensitivity of two symbiotic lichen microalgae, Asterochloris erici and Trebouxia sp. TR9, to atrazine was evaluated. To achieve this goal, axenic cultures of these phycobionts in suspension were exposed to a range of environmental concentrations of the herbicide atrazine, a common water pollutant. Optical density and chlorophyll autofluorescence were used as endpoints of ecotoxicity and ecophysiology on cell suspensions. Results show that lichen microalgae show high sensitivity to very low doses of atrazine, being higher in Asterochloris erici than in Trebouxia sp. TR9. We conclude that environmental concentrations of atrazine could modify population dynamics probably through a shift in reproduction strategies of these organisms. This seminal work is a breakthrough in the use of lichen microalgae in the assessment of micropollution effects on biodiversity.

  13. Multifocal lichen sclerosus. Case report

    Directory of Open Access Journals (Sweden)

    Ewa Hadas

    2015-03-01

    Full Text Available Introduction. Lichen sclerosus (LS is a chronic, inflammatory dermatosis of unknown etiology affecting skin and mucous membranes. It was first described in 1887 by Darier. Lichen sclerosus usually begins as a single or multiple plaques (rarely as lichenoid papules gradually transforming into porcelain-white atrophic lesions. Depending on localization, it may manifest with itching, pain or a burning sensation and often may cause sexual dysfunction. Objective. Presentation of an LS case that posed diagnostic difficulties. Case report. We present a patient with clinical diagnosis of lichen planus hypertrophicus on the skin of forearms and hands which demonstrated histopathological features of LS. Additionally, the presence of LS lesions was found on the skin of the eyelid and penis. Conclusions . Our case seems to be interesting because of the differences between clinical and histopathological findings and multiple localization of lesions.

  14. Co-niche construction between hosts and symbionts

    Indian Academy of Sciences (India)

    Symbiosis is a process that can generate evolutionary novelties and can extend the phenotypic niche space of organisms. Symbionts can act together with their hosts to co-construct host organs, within which symbionts are housed. Once established within hosts, symbionts can also influence various aspects of host ...

  15. Relationship of the luminous bacterial symbiont of the Caribbean flashlight fish, Kryptophanaron alfredi (family Anomalopidae) to other luminous bacteria based on bacterial luciferase (luxA) genes.

    Science.gov (United States)

    Haygood, M G

    1990-01-01

    Flashlight fishes (family Anomalopidae) have light organs that contain luminous bacterial symbionts. Although the symbionts have not yet been successfully cultured, the luciferase genes have been cloned directly from the light organ of the Caribbean species, Kryptophanaron alfredi. The goal of this project was to evaluate the relationship of the symbiont to free-living luminous bacteria by comparison of genes coding for bacterial luciferase (lux genes). Hybridization of a lux AB probe from the Kryptophanaron alfredi symbiont to DNAs from 9 strains (8 species) of luminous bacteria showed that none of the strains tested had lux genes highly similar to the symbiont. The most similar were a group consisting of Vibrio harveyi, Vibrio splendidus and Vibrio orientalis. The nucleotide sequence of the luciferase alpha subunit gene luxA) of the Kryptophanaron alfredi symbiont was determined in order to do a more detailed comparison with published luxA sequences from Vibrio harveyi, Vibrio fischeri and Photobacterium leiognathi. The hybridization results, sequence comparisons and the mol% G + C of the Kryptophanaron alfredi symbiont luxA gene suggest that the symbiont may be considered as a new species of luminous Vibrio related to Vibrio harveyi.

  16. Lichen planus hypertrophicus of the vulva - a rare entity.

    Science.gov (United States)

    Job, Anupa Mary; Kaimal, Sowmya

    2017-09-01

    Vulvovaginal lichen planus is a type of chronic inflammatory dermatosis of the vulva, usually seen as a part of widespread lichen planus. The common clinical types of vulval lichen planus include papulosquamous, erosive and pigmented types. Hypertrophic lichen planus of the vulva is a rare entity. We report a case of hypertrophic lichen planus of the vulva which clinically simulated genital warts.

  17. Lichen flora of Tomaszow Mazowiecki

    Energy Technology Data Exchange (ETDEWEB)

    Rydzak, J; Krysiak, K

    1970-01-01

    In Tomaszow Mazowiecki, a small town in Poland with the air highly contaminated with gases (SO/sub 2/, CS/sub 2/, H/sub 2/S), a flora of epiphytic and epilithic lichens is present. Lichens are not indicators of air pollution. They are indicators of a complex of microclimatic conditions that enable them to maintain a positive balance of assimilation and of respiratory processes in a given station within the town as well as in natural habitats. 58 references, 16 figures, 7 tables.

  18. Extragenital lichen sclerosus et atrophicus

    Directory of Open Access Journals (Sweden)

    Leelavathy Ganesan

    2015-01-01

    Full Text Available Lichen sclerosus et atrophicus (LSA is a chronic inflammatory dermatosis with anogenital and extragenital presentations. Extragenital lichen sclerosus is most common on the neck, shoulders and upper trunk. Linear lesions are uncommon in LSA. We report a case of linear extragenital LSA involving forehead and scalp, along with grouped white papules of LSA in the right side of the back in a postmenopausal woman. The patient showed atypical clinical presentation of LSA in face which clinically mimicked ′en coup de sabre′ as seen in morphea, but other clinical features suggested the diagnosis of LSA and the histopathological findings confirmed it.

  19. Algal carbohydrates affect polyketide synthesis of the lichen-forming fungus Cladonia rangiferina.

    Science.gov (United States)

    Elshobary, Mostafa E; Osman, Mohamed E; Abo-Shady, Atef M; Komatsu, Emy; Perreault, Hélène; Sorensen, John; Piercey-Normore, Michele D

    2016-01-01

    Lichen secondary metabolites (polyketides) are produced by the fungal partner, but the role of algal carbohydrates in polyketide biosynthesis is not clear. This study examined whether the type and concentration of algal carbohydrate explained differences in polyketide production and gene transcription by a lichen fungus (Cladonia rangiferina). The carbohydrates identified from a free-living cyanobacterium (Spirulina platensis; glucose), a lichen-forming alga (Diplosphaera chodatii; sorbitol) and the lichen alga that associates with C. rangiferina (Asterochloris sp.; ribitol) were used in each of 1%, 5% and 10% concentrations to enrich malt yeast extract media for culturing the mycobiont. Polyketides were determined by high performance liquid chromatography (HPLC), and polyketide synthase (PKS) gene transcription was measured by quantitative PCR of the ketosynthase domain of four PKS genes. The lower concentrations of carbohydrates induced the PKS gene expression where ribitol up-regulated CrPKS1 and CrPKS16 gene transcription and sorbitol up-regulated CrPKS3 and CrPKS7 gene transcription. The HPLC results revealed that lower concentrations of carbon sources increased polyketide production for three carbohydrates. One polyketide from the natural lichen thallus (fumarprotocetraric acid) also was produced by the fungal culture in ribitol supplemented media only. This study provides a better understanding of the role of the type and concentration of the carbon source in fungal polyketide biosynthesis in the lichen Cladonia rangiferina. © 2016 by The Mycological Society of America.

  20. Environmental Transmission of the Gut Symbiont Burkholderia to Phloem-Feeding Blissus insularis.

    Science.gov (United States)

    Xu, Yao; Buss, Eileen A; Boucias, Drion G

    2016-01-01

    The plant-phloem-feeding Blissus insularis possesses specialized midgut crypts, which harbor a dense population of the exocellular bacterial symbiont Burkholderia. Most individual B. insularis harbor a single Burkholderia ribotype in their midgut crypts; however, a diverse Burkholderia community exists within a host population. To understand the mechanism underlying the consistent occurrence of various Burkholderia in B. insularis and their specific association, we investigated potential gut symbiont transmission routes. PCR amplification detected a low titer of Burkholderia in adult reproductive tracts; however, fluorescence in situ hybridization assays failed to produce detectable signals in these tracts. Furthermore, no Burkholderia-specific PCR signals were detected in eggs and neonates, suggesting that it is unlikely that B. insularis prenatally transmits gut symbionts via ovarioles. In rearing experiments, most nymphs reared on St. Augustinegrass treated with cultured Burkholderia harbored the cultured Burkholderia strains. Burkholderia was detected in the untreated host grass of B. insularis, and most nymphs reared on untreated grass harbored a Burkholderia ribotype that was closely related to a plant-associated Burkholderia strain. These findings revealed that B. insularis neonates acquired Burkholderia primarily from the environment (i.e., plants and soils), even though the possibility of acquisition via egg surface cannot be excluded. In addition, our study explains how the diverse Burkholderia symbiont community in B. insularis populations can be maintained.

  1. Potential applications of insect symbionts in biotechnology.

    Science.gov (United States)

    Berasategui, Aileen; Shukla, Shantanu; Salem, Hassan; Kaltenpoth, Martin

    2016-02-01

    Symbiotic interactions between insects and microorganisms are widespread in nature and are often the source of ecological innovations. In addition to supplementing their host with essential nutrients, microbial symbionts can produce enzymes that help degrade their food source as well as small molecules that defend against pathogens, parasites, and predators. As such, the study of insect ecology and symbiosis represents an important source of chemical compounds and enzymes with potential biotechnological value. In addition, the knowledge on insect symbiosis can provide novel avenues for the control of agricultural pest insects and vectors of human diseases, through targeted manipulation of the symbionts or the host-symbiont associations. Here, we discuss different insect-microbe interactions that can be exploited for insect pest and human disease control, as well as in human medicine and industrial processes. Our aim is to raise awareness that insect symbionts can be interesting sources of biotechnological applications and that knowledge on insect ecology can guide targeted efforts to discover microorganisms of applied value.

  2. In vitro receptivity of carbonate rocks to endolithic lichen-forming aposymbionts.

    Science.gov (United States)

    Favero-Longo, Sergio E; Borghi, Alessandro; Tretiach, Mauro; Piervittori, Rosanna

    2009-10-01

    Sterile cultured isolates of lichen-forming aposymbionts have not yet been used to investigate lichen-rock interactions under controlled conditions. In this study mycobionts and photobiont of the endolithic lichens Bagliettoa baldensis and Bagliettoa marmorea were isolated and inoculated with coupons of one limestone and four marbles commonly employed in the Cultural Heritage framework. After one year of incubation, microscopic observations of polished cross-sections were performed to verify if the typical colonization patterns observed in the field may be reproduced in vitro and to evaluate the receptivity of the five lithotypes to endolithic lichens. The mycobionts of the two species developed both on the surface of and within all the lithotypes, showing different penetration pathways which depend on mineralogical and structural features and highlight different receptivity. By contrast, algae inoculated with the coupons did not penetrate them. Observations suggest that the hyphal penetration along intrinsic discontinuities of rocks is a relatively fast phenomenon when these organisms are generally considered as slow-growing. Samples from limestone outcrops and abandoned marble quarries, colonized by the same species or other representatives of Verrucariaceae, showed penetration pathways intriguingly similar to those reproduced in vitro and highlighted that lichen-driven erosion processes only increase the availability of hyphal passageways after a long-term colonization. These results show that in vitro incubation of sterile cultured lichen-forming ascomycetes with rock coupons is a practicable experimental system to investigate the lichen-rock interactions under controlled conditions and, together with analysis in situ, may support decisions on conservative treatments of historical and cultural significant stone substrata.

  3. Reflectance spectra of subarctic lichens

    International Nuclear Information System (INIS)

    Petzold, D.E.; Goward, S.N.

    1988-01-01

    Lichens constitute a major portion of the ground cover of high latitude environments, but little has been reported concerning their in situ solar spectral reflectance properties. Knowledge of these properties is important for the interpretation of remotely sensed observations from high latitude regions, as well as in studies of high latitude ecology and energy balance climatology. The spectral reflectance of common boreal vascular plants is similar to that of vascular plants of the mid latitudes. The dominant lichens, in contrast, display variable reflectance patterns in visible wavelengths. The relative reflectance peak at 0.55 μm, common to green vegetation, is absent or indistinct in spectra of pervasive boreal forest and tundra lichens, despite the presence of chlorophyll in the inner algal cells. Lichens of the dominant genus, Cladina, display strong absorption of ultraviolet energy and short-wavelength blue light relative to their absorption in other visible wavelengths. Since the Cladinae dominate both the surface vegetation in open woodlands of the boreal forest and the low arctic tundra, their unusual spectral reflectance patterns will enable accurate monitoring of the boreal forest-tundra ecotone and detection of its vigor and movement in the future. (author)

  4. Reflectance spectra of subarctic lichens

    Science.gov (United States)

    Petzold, Donald E.; Goward, Samuel N.

    1988-01-01

    Lichens constitute a major portion of the ground cover of high latitude environments, but little has been reported concerning their in situ solar spectral reflectance properties. Knowledge of these properties is important for the interpretation of remotely sensed observations from high latitude regions, as well as in studies of high latitude ecology and energy balance climatology. The spectral reflectance of common boreal vascular plants is similar to that of vascular plants of the midlatitudes. The dominant lichens, in contrast, display variable reflectance patterns in visible wavelengths. The relative reflectance peak at 0.55 microns, common to green vegetation, is absent or indistinct in spectra of pervasive boreal forest and tundra lichens, despite the presence of chlorophyll in the inner algal cells. Lichens of the dominant genus, Cladina, display strong absorption of ultraviolet energy and short-wavelength blue light relative to their absorption in other visible wavelengths. Since the Cladinae dominate both the surface vegetation in open woodlands of the boreal forest and the low arctic tundra, their unusual spectral reflectance patterns will enable accurate monitoring of the boreal forest-tundra ecotone and detection of its vigor and movement in the future.

  5. Life at the limits: peculiar features of lichen symbiosis related to extreme environmental factors

    Science.gov (United States)

    de Vera, J.-P.; Horneck, G.; Rettberg, P.; Ott, S.

    A lichen is a symbiotic association formed by a mycobiont (fungi), a photobiont (algae) and/or a cyanobacteria. The special symbiotic contact and interaction between the bionts in a lichen is a prerequisite for maintainance of viability for each of them during influences by harsh environmental factors. In nature parameters like UV radiation, low or high temperatures and dryness may have a destructive impact on all life functions of an organism. But with lichens the evolution has created a peculiar symbiosis which enables a wide variety of lichen species to colonize habitats where their separate bionts would not be able to survive. The results of our investigations are demonstrating these aspects (de Vera et al. 2003, 2004).We have already investigated the viability of the entire lichen thallus, the embedded spores in lichen apothecia (fruiting bodies) as well as the isolated spores and isolated photobionts after exposure to most extreme conditions caused by simulated space parameters as extreme UV radiation and vacuum. The results presented here focuse on the survival capacity of the isolated photobionts from the two lichen species Xanthoria elegans and Fulgensia bracteata which are not protected by the fungal structure of the lichen thallus. They are based on examinations using a Confocal Laser Scanning Microscopy (CLSM), analysed by modern methods of the Image Tool Program and by culture experiments. In contrast to photobionts embedded in the entire lichen thallus the isolated photobionts are much more sensitve to the extreme conditions of UV radiation and vaccum: while 50 % of the bionts in an entire lichen thallus are able to cope with simulated extreme space conditions (UV-radiation: λ quad ≥ 160nm and vacuum: p = 10-5 Pa) during an exposure time of 2 weeks, the viability of the isolated photobiont cells was already decreasing after 2 hours of exposure. All photobiont cells were inactivated after longer exposure times of about 8 hours. Further more analysis

  6. Low genetic diversity in Antarctic populations of the lichen-forming ascomycete Cetraria aculeata and its photobiont

    Directory of Open Access Journals (Sweden)

    Stephanie Domaschke

    2012-03-01

    Full Text Available Lichens, symbiotic associations of fungi (mycobionts and green algae or cyanobacteria (photobionts, are poikilohydric organisms that are particularly well adapted to withstand adverse environmental conditions. Terrestrial ecosystems of the Antarctic are therefore largely dominated by lichens. The effects of global climate change are especially pronounced in the maritime Antarctic and it may be assumed that the lichen vegetation will profoundly change in the future. The genetic diversity of populations is closely correlated to their ability to adapt to changing environmental conditions and to their future evolutionary potential. In this study, we present evidence for low genetic diversity in Antarctic mycobiont and photobiont populations of the widespread lichen Cetraria aculeata. We compared between 110 and 219 DNA sequences from each of three gene loci for each symbiont. A total of 222 individuals from three Antarctic and nine antiboreal, temperate and Arctic populations were investigated. The mycobiont diversity is highest in Arctic populations, while the photobionts are most diverse in temperate regions. Photobiont diversity decreases significantly towards the Antarctic but less markedly towards the Arctic, indicating that ecological factors play a minor role in determining the diversity of Antarctic photobiont populations. Richness estimators calculated for the four geographical regions suggest that the low genetic diversity of Antarctic populations is not a sampling artefact. Cetraria aculeata appears to have diversified in the Arctic and subsequently expanded its range into the Southern Hemisphere. The reduced genetic diversity in the Antarctic is most likely due to founder effects during long-distance colonization.

  7. Atmospheric pollution and specific tolerance of lichens

    Energy Technology Data Exchange (ETDEWEB)

    De Sloover, J

    1968-01-01

    An ecological method has been designed which allows a quantitative estimation of specific sensitivity of lichens to atmospheric pollution. That method is based on a comparison of the ''cortege moyen specifique'' i.e. the mean number of lichens growing with each species in a given area. Four of the obtained sequences are compared (The Dender valley and the area surrounding Gand, Belgium: the Oslo and the Helsinki areas); they show the order to toxiphoby of the related epiphytic lichens.

  8. Comparative Genomics of Facultative Bacterial Symbionts Isolated from European Orius Species Reveals an Ancestral Symbiotic Association

    Directory of Open Access Journals (Sweden)

    Xiaorui Chen

    2017-10-01

    Full Text Available Pest control in agriculture employs diverse strategies, among which the use of predatory insects has steadily increased. The use of several species within the genus Orius in pest control is widely spread, particularly in Mediterranean Europe. Commercial mass rearing of predatory insects is costly, and research efforts have concentrated on diet manipulation and selective breeding to reduce costs and improve efficacy. The characterisation and contribution of microbial symbionts to Orius sp. fitness, behaviour, and potential impact on human health has been neglected. This paper provides the first genome sequence level description of the predominant culturable facultative bacterial symbionts associated with five Orius species (O. laevigatus, O. niger, O. pallidicornis, O. majusculus, and O. albidipennis from several geographical locations. Two types of symbionts were broadly classified as members of the genera Serratia and Leucobacter, while a third constitutes a new genus within the Erwiniaceae. These symbionts were found to colonise all the insect specimens tested, which evidenced an ancestral symbiotic association between these bacteria and the genus Orius. Pangenome analyses of the Serratia sp. isolates offered clues linking Type VI secretion system effector–immunity proteins from the Tai4 sub-family to the symbiotic lifestyle.

  9. Comparative Genomics of Facultative Bacterial Symbionts Isolated from European Orius Species Reveals an Ancestral Symbiotic Association

    Science.gov (United States)

    Chen, Xiaorui; Hitchings, Matthew D.; Mendoza, José E.; Balanza, Virginia; Facey, Paul D.; Dyson, Paul J.; Bielza, Pablo; Del Sol, Ricardo

    2017-01-01

    Pest control in agriculture employs diverse strategies, among which the use of predatory insects has steadily increased. The use of several species within the genus Orius in pest control is widely spread, particularly in Mediterranean Europe. Commercial mass rearing of predatory insects is costly, and research efforts have concentrated on diet manipulation and selective breeding to reduce costs and improve efficacy. The characterisation and contribution of microbial symbionts to Orius sp. fitness, behaviour, and potential impact on human health has been neglected. This paper provides the first genome sequence level description of the predominant culturable facultative bacterial symbionts associated with five Orius species (O. laevigatus, O. niger, O. pallidicornis, O. majusculus, and O. albidipennis) from several geographical locations. Two types of symbionts were broadly classified as members of the genera Serratia and Leucobacter, while a third constitutes a new genus within the Erwiniaceae. These symbionts were found to colonise all the insect specimens tested, which evidenced an ancestral symbiotic association between these bacteria and the genus Orius. Pangenome analyses of the Serratia sp. isolates offered clues linking Type VI secretion system effector–immunity proteins from the Tai4 sub-family to the symbiotic lifestyle. PMID:29067021

  10. Diverse strategies for vertical symbiont transmission among subsocial stinkbugs.

    Directory of Open Access Journals (Sweden)

    Takahiro Hosokawa

    Full Text Available Sociality may affect symbiosis and vice versa. Many plant-sucking stinkbugs harbor mutualistic bacterial symbionts in the midgut. In the superfamily Pentatomoidea, adult females excrete symbiont-containing materials from the anus, which their offspring ingest orally and establish vertical symbiont transmission. In many stinkbug families whose members are mostly non-social, females excrete symbiont-containing materials onto/beside eggs upon oviposition. However, exceptional cases have been reported from two subsocial species representing the closely related families Cydnidae and Parastrachiidae, wherein females remain nearby eggs for maternal care after oviposition, and provide their offspring with symbiont-containing secretions at later stages, either just before or after hatching. These observations suggested that sociality of the host stinkbugs may be correlated with their symbiont transmission strategies. However, we found that cydnid stinkbugs of the genus Adomerus, which are associated with gammaproteobacterial gut symbionts and exhibit elaborate maternal care over their offspring, smear symbiont-containing secretions onto eggs upon oviposition as many non-social stinkbugs do. Surface sterilization of the eggs resulted in aposymbiotic insects of slower growth, smaller size and abnormal body coloration, indicating vertical symbiont transmission via egg surface contamination and presumable beneficial nature of the symbiosis. The Adomerus symbionts exhibited AT-biased nucleotide compositions, accelerated molecular evolutionary rates and reduced genome size, while these degenerative genomic traits were less severe than those in the symbiont of a subsocial parastrachiid. These results suggest that not only sociality but also other ecological and evolutionary aspects of the host stinkbugs, including the host-symbiont co-evolutionary history, may have substantially affected their symbiont transmission strategies.

  11. Lichens: Unexpected anti-prion agents?

    Science.gov (United States)

    Rodriguez, Cynthia M.; Bennett, James P.; Johnson, Christopher J.

    2012-01-01

    The prion diseases sheep scrapie and cervid chronic wasting disease are transmitted, in part, via an environmental reservoir of infectivity; prions released from infected animals persist in the environment and can cause disease years later. Central to controlling disease transmission is the identification of methods capable of inactivating these agents on the landscape. We have found that certain lichens, common, ubiquitous, symbiotic organisms, possess a serine protease capable of degrading prion protein (PrP) from prion-infected animals. The protease functions against a range of prion strains from various hosts and reduces levels of abnormal PrP by at least two logs. We have now tested more than 20 lichen species from several geographical locations and from various taxa and found that approximately half of these species degrade PrP. Critical next steps include examining the effect of lichens on prion infectivity and cloning the protease responsible for PrP degradation. The impact of lichens on prions in the environment remains unknown. We speculate that lichens could have the potential to degrade prions when they are shed from infected animals onto lichens or into environments where lichens are abundant. In addition, lichens are frequently consumed by cervids and many other animals and the effect of dietary lichens on prion disease transmission should also be considered.

  12. Linear lichen planus in children - Case report*

    Science.gov (United States)

    Horowitz, Marcia Raquel; Vidal, Marcela de Lima; Resende, Manuela Oliveira; Teixeira, Márcia Almeida Galvão; Cavalcanti, Silvana Maria de Morais; de Alencar, Eliane Ruth Barbosa

    2013-01-01

    Lichen planus is an uncommon disease in children, and only 2 to 3% of affected patients are under twenty years of age. This dermatosis may appear in several clinical forms, which vary according to the morphology and distribution of lesions. In less than 0.2% of all lichen planus cases, the lesions are distributed along the lines of Blaschko, and is a variant called linear lichen planus. This is a case report of a patient aged two years and eight months, who presented keratotic violaceous papules, affecting the abdomen, buttocks and right thigh, distributed along the lines of Blaschko. Histopathological examination confirmed a diagnosis of linear lichen planus. PMID:24346902

  13. Nitrogen and carbon isotope variability in the green-algal lichen Xanthoria parietina and their implications on mycobiont–photobiont interactions

    Science.gov (United States)

    Beck, Andreas; Mayr, Christoph

    2012-01-01

    Stable isotope patterns in lichens are known to vary largely, but effects of substrate on carbon and nitrogen stable isotope signatures of lichens were previously not investigated systematically. N and C contents and stable isotope (δ15N, δ13C) patterns have been measured in 92 lichen specimens of Xanthoria parietina from southern Bavaria growing on different substrates (bark and stone). Photobiont and mycobiont were isolated from selected populations and isotopically analyzed. Molecular investigations of the internal transcribed spacer of the nuclear ribosomal DNA (ITS nrDNA) region have been conducted on a subset of the specimens of X. parietina. Phylogenetic analysis showed no correlation between the symbionts X. parietina and Trebouxia decolorans and the substrate, isotope composition, or geographic origin. Instead specimens grown on organic substrate significantly differ in isotope values from those on minerogenic substrate. This study documents that the lichens growing on bark use additional or different N sources than the lichens growing on stone. δ15N variation of X. parietina apparently is controlled predominantly by the mass fraction of the mycobiont and its nitrogen isotope composition. In contrast with mycobionts, photobionts of X. parietina are much more 15N-depleted and show less isotopic variability than mycobionts, probably indicating a mycobiont-independent nitrogen acquisition by uptake of atmospheric ammonia. PMID:23301178

  14. Symbiotic Interplay of Fungi, Algae, and Bacteria within the Lung Lichen Lobaria pulmonaria L. Hoffm. as Assessed by State-of-the-Art Metaproteomics.

    Science.gov (United States)

    Eymann, Christine; Lassek, Christian; Wegner, Uwe; Bernhardt, Jörg; Fritsch, Ole Arno; Fuchs, Stephan; Otto, Andreas; Albrecht, Dirk; Schiefelbein, Ulf; Cernava, Tomislav; Aschenbrenner, Ines; Berg, Gabriele; Grube, Martin; Riedel, Katharina

    2017-06-02

    Lichens are recognized by macroscopic structures formed by a heterotrophic fungus, the mycobiont, which hosts internal autotrophic photosynthetic algal and/or cyanobacterial partners, referred to as the photobiont. We analyzed the structure and functionality of the entire lung lichen Lobaria pulmonaria L. Hoffm. collected from two different sites by state-of-the-art metaproteomics. In addition to the green algae and the ascomycetous fungus, a lichenicolous fungus as well as a complex prokaryotic community (different from the cyanobacteria) was found, the latter dominated by methanotrophic Rhizobiales. Various partner-specific proteins could be assigned to the different lichen symbionts, for example, fungal proteins involved in vesicle transport, algal proteins functioning in photosynthesis, cyanobacterial nitrogenase and GOGAT involved in nitrogen fixation, and bacterial enzymes responsible for methanol/C1-compound metabolism as well as CO-detoxification. Structural and functional information on proteins expressed by the lichen community complemented and extended our recent symbiosis model depicting the functional multiplayer network of single holobiont partners.1 Our new metaproteome analysis strongly supports the hypothesis (i) that interactions within the self-supporting association are multifaceted and (ii) that the strategy of functional diversification within the single lichen partners may support the longevity of L. pulmonaria under certain ecological conditions.

  15. Fiber, food, fuel, and fungal symbionts.

    Science.gov (United States)

    Ruehle, J L; Marx, D H

    1979-10-26

    Virtually all plants of economic importance form mycorrhizae. These absorbing organs of higher plants result from a symbiotic union of beneficial soil fungi and feeder roots. In forestry, the manipulation of fungal symbionts ecologically adapted to the planting site can increase survival and growth of forest trees, particularly on adverse sites. Vesicular-arbuscular mycorrhizae, which occur not only on many trees but also on most cultivated crops, are undoubtedly more important to world food crops. Imperatives for mycorrhizal research in forestry and agriculture are (i) the development of mass inoculum of mycorrhizal fungi, (ii) the interdisciplinary coordination with soil management, plant breeding, cultivation practices, and pest control to ensure maximum survival and development of fungal symbionts in the soil, and (iii) the institution of nursery and field tests to determine the circumstances in which mycorrhizae benefit plant growth in forestry and agri-ecosystems.

  16. Social insect symbionts: evolution in homeostatic fortresses

    DEFF Research Database (Denmark)

    Hughes, David P; Pierce, Naomi E; Boomsma, Jacobus J

    2008-01-01

    The massive environmentally buffered nests of some social insects can contain millions of individuals and a wide variety of parasites, commensals and mutualists. We suggest that the ways in which these homeostatic fortress environments affect the evolution of social insect symbionts are relevant...... in these nests. We hypothesize that biodiversity gradients in these hotspots might be less affected by abiotic latitudinal clines than gradients in neighboring 'control' habitats. We suggest several research lines to test these ideas....

  17. The Calyptogena magnifica chemoautotrophic symbiont genome

    Energy Technology Data Exchange (ETDEWEB)

    Newton, I.L.; Woyke, T.; Auchtung, T.A.; Dilly, G.F.; Dutton,R.J.; Fisher, M.C.; Fontanez, K.M.; Lau, E.; Stewart, F.J.; Richardson,P.M.; Barry, K.W.; Saunders, E.; Detter, J.C.; Wu, D.; Eisen, J.A.; Cavanaugh, C.M.

    2007-03-01

    Chemoautotrophic endosymbionts are the metabolic cornerstone of hydrothermal vent communities, providing invertebrate hosts with nearly all of their nutrition. The Calyptogena magnifica (Bivalvia: Vesicomyidae) symbiont, Candidatus Ruthia magnifica, is the first intracellular sulfur-oxidizing endosymbiont to have its genome sequenced, revealing a suite of metabolic capabilities. The genome encodes major chemoautotrophic pathways as well as pathways for biosynthesis of vitamins, cofactors, and all 20 amino acids required by the clam.

  18. Epiphytic lichens and air pollution

    Energy Technology Data Exchange (ETDEWEB)

    De Wit, T

    1978-01-01

    The WHEN workgroup has made an inventory of the epiphytic lichens on freestanding trees in The Netherlands, using a 5 km square-grid as a basis. On the basis of the number of lichen species per tree species per square, the squares were divided into six classes of epiphyte richness. The data for the west of the country were analyzed in more detail, resulting in a zone map. It appeared possible to construct a descriptive model of the correlation between SO/sub 2/ concentrations and epiphyte richness. At median winter SO/sub 2/ concentrations higher than 100..mu..g/m/sup 3/ only a few insensitive species occur. At lower concentrations winter peak values (98 percentile) are more important than median ones. The extent to which a species is restricted to epiphyte-rich squares is used as a measure for ranking the species according to sensitivity. The more sensitive species have disappeared from large areas of The Netherlands. Comparison of the present situation with data from around 1950 reveals a decline almost everywhere in the country. The southern and western parts of the country are impoverished, the area between Rotterdam and Den Haag and the area between Arnhem and Nijmegen in particular have become very poor. A further decline of the epiphytic lichen vegetation, in particular of the relatively rich areas, is expected. In fumigation experiments, using HF, SO/sub 2/, C/sub 2/H/sub 4/, O/sub 3/ and O/sub 3/ combined with SO/sub 2/ at realistic concentrations and prolonged exposition it was found that these air pollutants cause (under glasshouse conditions) significant morphological damage to all or some of the tested lichen species.

  19. Horizontal Transmission of Intracellular Insect Symbionts via Plants

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    Ewa Chrostek

    2017-11-01

    Full Text Available Experimental evidence is accumulating that endosymbionts of phytophagous insects may transmit horizontally via plants. Intracellular symbionts known for manipulating insect reproduction and altering fitness (Rickettsia, Cardinium, Wolbachia, and bacterial parasite of the leafhopper Euscelidius variegatus have been found to travel from infected insects into plants. Other insects, either of the same or different species can acquire the symbiont from the plant through feeding, and in some cases transfer it to their progeny. These reports prompt many questions regarding how intracellular insect symbionts are delivered to plants and how they affect them. Are symbionts passively transported along the insect-plant-insect path, or do they actively participate in the process? How widespread are these interactions? How does symbiont presence influence the plant? And what conditions are required for the new infection to establish in an insect? From an ecological, evolutionary, and applied perspective, this mode of horizontal transmission could have profound implications if occurring frequently enough or if new stable symbiont infections are established. Transmission of symbionts through plants likely represents an underappreciated means of infection, both in terms of symbiont epidemiology and the movement of symbionts to new host species.

  20. Effects of ocean acidification on calcification of symbiont-bearing reef foraminifers

    Science.gov (United States)

    Fujita, K.; Hikami, M.; Suzuki, A.; Kuroyanagi, A.; Sakai, K.; Kawahata, H.; Nojiri, Y.

    2011-08-01

    Ocean acidification (decreases in carbonate ion concentration and pH) in response to rising atmospheric pCO2 is generally expected to reduce rates of calcification by reef calcifying organisms, with potentially severe implications for coral reef ecosystems. Large, algal symbiont-bearing benthic foraminifers, which are important primary and carbonate producers in coral reefs, produce high-Mg calcite shells, whose solubility can exceed that of aragonite produced by corals, making them the "first responder" in coral reefs to the decreasing carbonate saturation state of seawater. Here we report results of culture experiments performed to assess the effects of ongoing ocean acidification on the calcification of symbiont-bearing reef foraminifers using a high-precision pCO2 control system. Living clone individuals of three foraminiferal species (Baculogypsina sphaerulata, Calcarina gaudichaudii, and Amphisorus hemprichii) were subjected to seawater at five pCO2 levels from 260 to 970 μatm. Cultured individuals were maintained for about 12 weeks in an indoor flow-through system under constant water temperature, light intensity, and photoperiod. After the experiments, the shell diameter and weight of each cultured specimen were measured. Net calcification of B. sphaerulata and C. gaudichaudii, which secrete a hyaline shell and host diatom symbionts, increased under intermediate levels of pCO2 (580 and/or 770 μatm) and decreased at a higher pCO2 level (970 μatm). Net calcification of A. hemprichii, which secretes a porcelaneous shell and hosts dinoflagellate symbionts, tended to decrease at elevated pCO2. Observed different responses between hyaline and porcelaneous species are possibly caused by the relative importance of elevated pCO2, which induces CO2 fertilization effects by algal symbionts, versus associated changes in seawater carbonate chemistry, which decreases a carbonate concentration. Our findings suggest that ongoing ocean acidification might favor symbiont

  1. Effects of ocean acidification on calcification of symbiont-bearing reef foraminifers

    Directory of Open Access Journals (Sweden)

    K. Fujita

    2011-08-01

    Full Text Available Ocean acidification (decreases in carbonate ion concentration and pH in response to rising atmospheric pCO2 is generally expected to reduce rates of calcification by reef calcifying organisms, with potentially severe implications for coral reef ecosystems. Large, algal symbiont-bearing benthic foraminifers, which are important primary and carbonate producers in coral reefs, produce high-Mg calcite shells, whose solubility can exceed that of aragonite produced by corals, making them the "first responder" in coral reefs to the decreasing carbonate saturation state of seawater. Here we report results of culture experiments performed to assess the effects of ongoing ocean acidification on the calcification of symbiont-bearing reef foraminifers using a high-precision pCO2 control system. Living clone individuals of three foraminiferal species (Baculogypsina sphaerulata, Calcarina gaudichaudii, and Amphisorus hemprichii were subjected to seawater at five pCO2 levels from 260 to 970 μatm. Cultured individuals were maintained for about 12 weeks in an indoor flow-through system under constant water temperature, light intensity, and photoperiod. After the experiments, the shell diameter and weight of each cultured specimen were measured. Net calcification of B. sphaerulata and C. gaudichaudii, which secrete a hyaline shell and host diatom symbionts, increased under intermediate levels of pCO2 (580 and/or 770 μatm and decreased at a higher pCO2 level (970 μatm. Net calcification of A. hemprichii, which secretes a porcelaneous shell and hosts dinoflagellate symbionts, tended to decrease at elevated pCO2. Observed different responses between hyaline and porcelaneous species are possibly caused by the relative importance of elevated pCO2, which induces CO2 fertilization effects by

  2. Lichens as source of versatile bioactive compounds

    Directory of Open Access Journals (Sweden)

    Mitrović, T.

    2011-09-01

    Full Text Available Lichens represent unique symbiosis of fungi (mycobionts and algae (photobionts. Living in extreme conditions they developed various compounds to survive. Many of these original compounds have proven biological activities (antibiotic, antimycotic, antiviral, antitumor, antioxidant, etc . This paper is synthesis of currently known data about lichens extracts and their potential use in pharmaceutics and medicine.

  3. The "Ride for Russia" Tree Lichen Survey

    Science.gov (United States)

    Young, Simon

    2013-01-01

    The prevalence of nine indicator lichens found on trees in Northern Europe and Western Russia was used for monitoring air quality. The 4200 mile route of the survey went through eight countries. Surveys were carried out in cities, towns, countryside and forests, and along motorways. The author has conducted tree lichen surveys with pupils from…

  4. Secondary metabolism in the lichen symbiosis.

    Science.gov (United States)

    Calcott, Mark J; Ackerley, David F; Knight, Allison; Keyzers, Robert A; Owen, Jeremy G

    2018-03-05

    Lichens, which are defined by a core symbiosis between a mycobiont (fungal partner) and a photobiont (photoautotrophic partner), are in fact complex assemblages of microorganisms that constitute a largely untapped source of bioactive secondary metabolites. Historically, compounds isolated from lichens have predominantly been those produced by the dominant fungal partner, and these continue to be of great interest for their unique chemistry and biotechnological potential. In recent years it has become apparent that many photobionts and lichen-associated bacteria also produce a range of potentially valuable molecules. There is evidence to suggest that the unique nature of the symbiosis has played a substantial role in shaping many aspects of lichen chemistry, for example driving bacteria to produce metabolites that do not bring them direct benefit but are useful to the lichen as a whole. This is most evident in studies of cyanobacterial photobionts, which produce compounds that differ from free living cyanobacteria and are unique to symbiotic organisms. The roles that these and other lichen-derived molecules may play in communication and maintaining the symbiosis are poorly understood at present. Nonetheless, advances in genomics, mass spectrometry and other analytical technologies are continuing to illuminate the wealth of biological and chemical diversity present within the lichen holobiome. Implementation of novel biodiscovery strategies such as metagenomic screening, coupled with synthetic biology approaches to reconstitute, re-engineer and heterologously express lichen-derived biosynthetic gene clusters in a cultivable host, offer a promising means for tapping into this hitherto inaccessible wealth of natural products.

  5. Verrucous Lichen Planus: A Rare Presentation of a Common Condition

    Science.gov (United States)

    Audhya, Moutusi; Varughese, Jenny S.; Nakhwa, Yuti C.

    2014-01-01

    Lichen planus is a chronic papulosquamous dermatoses in which both skin and mucosae are involved. There are various morphological forms of lichen planus. Hypertrophic lichen planus is one of the rare clinical variants. Herein, we report a very unusual presentation of hypertrophic lichen planus. A similar presentation has not been reported in literature yet, to the best of our knowledge. PMID:25386324

  6. A Case of Lichen Planus Pigmentosus-Inversus

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    Belkız Uyar

    2012-09-01

    Full Text Available Lichen planus pigmentosus is a rare subtype of lichen planus. Because of its rarity, we present the case of a patient diagnosed as lichen planus pigmentosus-inversus based on clinical and histopatological findings, which clinical appearance did not resemble lichen planus at initial examination.

  7. Reindeer lichen productivity: Problems and possibilities

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    Bjartmar Sveinbjörnsson

    1990-09-01

    Full Text Available Reindeer lichens are important in the structure and function of tundra and taiga ecosystems, as exemplified by cover values, biomass, mineral content, and effect on other ecosystem components. They are particularly important for winter ecology of reindeer and caribou which largely relay on them. Growth measurement is difficult due to the very slow rate and the methods that have been used are not sufficiently documented, precise, or appropriate. Use of carbon dioxide exchange models, coupled with models of lichen microclimate and water relations, based on microclimatic data are suggested as alternatives for land managers. The assumptions of such models are discussed and the performance of mixed species lichen mats and of the lichen CO2 environment and its effect on lichen CO2 exchange.

  8. MALIGNANT TRANSFORMATION OF EROSIVE ORAL LICHEN PLANUS

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    Siti Chumaeroh

    2006-04-01

    Full Text Available Lichen planus is a relatively common inflammatory disorder which may have cutaneous and or mucosal manifestation. The malignant potential of oral lichen planus is still debatable. Some authors are sceptical about the premalignant nature of the disease, while other investigators have reported that malignant transformations occur in 1-10% of the cases. The aim of this study is to report a case of erosive lichen plans which shows malignant transformation of histopathologic examination. A man of 39 years old visited the Dental Department or Kajradi's Hospital with pain symptoms of the palate, buccal and gingival mucosa on both sides for 6 months. The physical examination shows the white lesion with striae configuration and pain, red erosive area inside the palate extends to the buccal mucosa and the gingival mucosa. The suspect diagnosis is erosive lichen planus, but the histopathologic examination shows epidermoid carcinoma. It is concluded that erosive oral lichen planus has the potential to transform into epidermoid carcinoma.

  9. Hydrology in Lichens: How Biological Architecture is Used to Regulate Water Access to Support Drought Resilience and Nutrient Transport

    Science.gov (United States)

    Ten Veldhuis, M. C.; Dismukes, G. C.; Ananyev, G.

    2017-12-01

    Lichens are Nature's masters at controlling water and air flux within a symbiotic organism comprised of an algal photobiont and its fungal host. Here we investigated the equilibrium partitioning and kinetic transport of water between the symbionts in the lichen flavoparmelia species. Lichens have developed a unique strategy to recover after deep dehydration, that otherwise would kill the majority of free living phototrophs. By measuring both kinetics of water content and chlorophyll fluorescence emission (indicative of algal charge separation and water oxidation) during dehydration, we identified 3 distinct temporal stages and mapped these to physical zones by confocal microscopy using a combination of hydro-philic/-phobic dyes. Below a critical level of water content, controlled by the greater hydrophilicity of fungal tissues, algal photosynthesis rapidly turns off. We show that the distinct stages in dehydration mirror the 3D architecture of lichen tissue (the thallus). We provide evidence that control of water distribution is achieved by capillary forces within ordered zones of physical space possessing different hydro-phobic/-philic characteristics. This strategy ensures that photosynthetic capacity is protected from and can quickly recover after desiccation. The fungal host controls the onset and extent of photosynthesis in the enslaved alga, presumably to ensure transport of algal derived sugars and oxygen (O2) to the fungal host only when sufficient water exists for transport. Lichen architecture provides Nature's solution to gas-water transport that is self-regulated by humidity. It offers novel lessons for designing practical devices such as fuel cell membranes and dialysis membranes. Supported by the US Dept of Energy, Basic Energy Sciences, Physical Biosciences Division.

  10. A CLINICAL AND HISTOPATHOLOGICAL STUDY OF LICHEN PLANUS

    OpenAIRE

    Ch. Madhu Babu; P. Padmaja; M. Roopa Shree

    2016-01-01

    BACKGROUND Lichen planus is an idiopathic subacute or chronic inflammatory disease of the skin, mucous membranes, and nails. We studied the clinicopathological profile of 50 cases of Lichen planus in Osmania General Hospital from September 2010-April 2012. METHODS A total of 50 cases Lichen planus attending DVL OPD at OGH were studied. Clinical features like age, sex, type of Lichen planus, location were recorded in the case record form. Histological features of Lichen planus...

  11. Combined thermal and herbicide stress in functionally diverse coral symbionts

    International Nuclear Information System (INIS)

    Dam, J.W. van; Uthicke, S.; Beltran, V.H.; Mueller, J.F.; Negri, A.P.

    2015-01-01

    Most reef building corals rely on symbiotic microalgae (genus Symbiodinium) to supply a substantial proportion of their energy requirements. Functional diversity of different Symbiodinium genotypes, endorsing the host with physiological advantages, has been widely reported. Yet, the influence of genotypic specificity on the symbiont's susceptibility to contaminants or cumulative stressors is unknown. Cultured Symbiodinium of presumed thermal-tolerant clade D tested especially vulnerable to the widespread herbicide diuron, suggesting important free-living populations may be at risk in areas subjected to terrestrial runoff. Co-exposure experiments where cultured Symbiodinium were exposed to diuron over a thermal stress gradient demonstrated how fast-growing clade C1 better maintained photosynthetic capability than clade D. The mixture toxicity model of Independent Action, considering combined thermal stress and herbicide contamination, revealed response additivity for inhibition of photosynthetic yield in both tested cultures, emphasizing the need to account for cumulative stressor impacts in ecological risk assessment and resource management. - Highlights: • Water quality influences thermal stress thresholds in different Symbiodinium types. • Photosystem of clade D tested more sensitive than C1 to a common herbicide. • Increased thermal tolerance quickly countered in presence of herbicide. • Mixture toxicity approach demonstrated response additivity for combined stressors. • Symbiotic partnership may be compromised in areas subjected to terrestrial runoff. - Thermal-tolerant Symbiodinium type D tested especially vulnerable to a common herbicide, emphasizing the significance of cumulative stressors in ecological risk management

  12. Comparative genomics of vesicomyid clam (Bivalvia: Mollusca chemosynthetic symbionts

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    Girguis Peter R

    2008-12-01

    Full Text Available Abstract Background The Vesicomyidae (Bivalvia: Mollusca are a family of clams that form symbioses with chemosynthetic gamma-proteobacteria. They exist in environments such as hydrothermal vents and cold seeps and have a reduced gut and feeding groove, indicating a large dependence on their endosymbionts for nutrition. Recently, two vesicomyid symbiont genomes were sequenced, illuminating the possible nutritional contributions of the symbiont to the host and making genome-wide evolutionary analyses possible. Results To examine the genomic evolution of the vesicomyid symbionts, a comparative genomics framework, including the existing genomic data combined with heterologous microarray hybridization results, was used to analyze conserved gene content in four vesicomyid symbiont genomes. These four symbionts were chosen to include a broad phylogenetic sampling of the vesicomyid symbionts and represent distinct chemosynthetic environments: cold seeps and hydrothermal vents. Conclusion The results of this comparative genomics analysis emphasize the importance of the symbionts' chemoautotrophic metabolism within their hosts. The fact that these symbionts appear to be metabolically capable autotrophs underscores the extent to which the host depends on them for nutrition and reveals the key to invertebrate colonization of these challenging environments.

  13. Standard methods for research on apis mellifera gut symbionts

    Science.gov (United States)

    Gut microbes can play an important role in digestion, disease resistance, and the general health of animals, but little is known about the biology of gut symbionts in Apis mellifera. This paper is part of a series on honey bee research methods, providing protocols for studying gut symbionts. We desc...

  14. Riptortus pedestris and Burkholderia symbiont: an ideal model system for insect-microbe symbiotic associations.

    Science.gov (United States)

    Takeshita, Kazutaka; Kikuchi, Yoshitomo

    2017-04-01

    A number of insects establish symbiotic associations with beneficial microorganisms in various manners. The bean bug Riptortus pedestris and allied stink bugs possess an environmentally acquired Burkholderia symbiont in their midgut crypts. Unlike other insect endosymbionts, the Burkholderia symbiont is easily culturable and genetically manipulatable outside the host. In conjunction with the experimental advantages of the host insect, the Riptortus-Burkholderia symbiosis is an ideal model system for elucidating the molecular bases underpinning insect-microbe symbioses, which opens a new window in the research field of insect symbiosis. This review summarizes current knowledge of this system and discusses future perspectives. Copyright © 2016 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

  15. Fibrinolytic protease production by new Streptomyces sp. DPUA 1576 from Amazon lichens

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    Germana M.M. Silva

    2015-01-01

    Conclusions: These results show that the optimization of the culture medium can enhance protease production, thus becoming a good process for further research. In addition, Streptomyces sp. DPUA 1576, isolated from Amazon lichens, might be a potential strain for fibrinolytic protease production.

  16. Reduced immune responses to purified protein derivative and Candida albicans in oral lichen planus.

    Science.gov (United States)

    Simark-Mattsson, Charlotte; Eklund, Christina

    2013-10-01

    Impairment of cellular immunity is reported in lichen planus, an autoimmune disease affecting mucosae and skin. Our aim was to investigate immune responses directed against a set of microbial antigens in patients with oral lichen planus and in matched controls. Venous blood was obtained, and the mononuclear cells were enriched by density gradient centrifugation. The proliferation of peripheral blood mononuclear cells was assessed, following stimulation with purified protein derivative (PPD), Candida albicans, phytohemagglutinin or when cells were left unstimulated, after three or six days of cell culture. The production of interleukin-1ß (IL-1ß), IL-2, IL-4, IL-5, IL-6, IL-10, IL-12, IL-13, IL-17, interferon-γ (IFN-γ), tumour necrosis factor-α (TNF-α), G-CSF, GM-CSF, MCP-1, MIP-ß was assessed in supernatants using the Bio-plex(®) assay and was complemented with ELISA for selected cytokines. Patients with oral lichen planus demonstrated reduced proliferative responses against PPD (P stimulated supernatants from patients with oral lichen planus. Collectively, the findings suggested that memory lymphocytes from patients with oral lichen planus (OLP) may have an impaired functional ability to react against certain recall antigens, as part of a generalized response, which may reflect immune regulatory processes. Further studies are needed to clarify the mechanisms of down-regulation in OLP pathogenesis and progression. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  17. Dermoscopic findings in extragenital lichen sclerosus

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    Anna Jędrowiak

    2017-08-01

    Full Text Available Lichen sclerosus (LS, also known as lichen sclerosus et atrophicus is a chronic inflammatory dermatosis of unknown aetiology. It has both genital and extragenital presentations, nevertheless genital forms significantly outnumber extragenital LS. Dermoscopy is noninvasive diagnostic tool traditionally employed in pigmented lesions, however its usefulness in inflammatory skin conditions is becoming continuously more meaningful. Although the clinical diagnosis of fully developed LS rarely causes difficulties, unusual presentations require differentiation from the diseases such as lichen planus, morphea, extramammary Paget disease, SCC and others. In these cases histopathology contributes to the diagnosis. Studies on the use of dermoscopy in LS are sparse, nevertheless some dermoscopic features of LS has been described.

  18. Dermoscopic findings in extragenital lichen sclerosus

    Directory of Open Access Journals (Sweden)

    Anna Jędrowiak

    2018-04-01

    Full Text Available Lichen sclerosus (LS, also known as lichen sclerosus et atrophicus is a chronic inflammatory dermatosis of unknown aetiology. It has both genital and extragenital presentations, nevertheless genital forms significantly outnumber extragenital LS. Dermoscopy is noninvasive diagnostic tool traditionally employed in pigmented lesions, however its usefulness in inflammatory skin conditions is becoming continuously more meaningful. Although the clinical diagnosis of fully developed LS rarely causes difficulties, unusual presentations require differentiation from the diseases such as lichen planus, morphea, extramammary Paget disease, SCC and others. In these cases histopathology contributes to the diagnosis. Studies on the use of dermoscopy in LS are sparse, nevertheless some dermoscopic features of LS has been described.

  19. Skull lichens: a curious chapter in the history of phytotherapy.

    Science.gov (United States)

    Modenesi, P

    2009-04-01

    Lichens growing on skulls were known in late medieval times as usnea or moss of a dead man's skull and were recommended as highly beneficial in various diseases. They were, in addition, the main ingredient of Unguentum armariun, a liniment used in a curious medical practice: the magnetic cure of wounds. We can place this chapter of the history of phytotherapy within the wider cultural context of the period, which saw the definition of nature become increasingly more fluid and open to a variety of novel interpretations.

  20. Vulvar lichen sclerosus et atrophicus

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    Pragya Ashok Nair

    2017-01-01

    Full Text Available Vulvar lichen sclerosus (VLS is a chronic inflammatory dermatosis characterized by ivory-white plaques or patches with glistening surface commonly affecting the vulva and anus. Common symptoms are irritation, soreness, dyspareunia, dysuria, and urinary or fecal incontinence. Anogenital lichen sclerosus (LS is characterized by porcelain-white atrophic plaques, which may become confluent extending around the vulval and perianal skin in a figure of eight configuration. Thinning and shrinkage of the genital area make coitus, urination, and defecation painful. LS is not uncommon in India and present as an itchy vulvar dermatosis which a gynecologist may mistake for candidal vulvovaginitis. There is often a delay in diagnosis of VLS due to its asymptomatic nature and lack of awareness in patients as well as physicians. Embarrassment of patients due to private nature of the disease and failure to examine the genital skin properly are the other reasons for delay in diagnosis. There is no curative treatment for LS. Various medications available only relieve the symptoms. Chronic nature of the disease affects the quality of life. Proper and regular follow-up is required as there are chances of the development of squamous cell carcinoma.

  1. Metal homeostasis in Hypogymnia physodes is controlled by lichen substances.

    Science.gov (United States)

    Hauck, Markus

    2008-05-01

    The hypothesis was tested that the lichen substances produced by the epiphytic lichen Hypogymnia physodes control the intracellular uptake of divalent transition metals. Incubating lichen thalli with and without their natural content of lichen substances with metal solutions showed that the lichen substances of H. physodes selectively inhibit the uptake of Cu(2+) and Mn(2+), but not of Fe(2+) and Zn(2+). Such behavior is ecologically beneficial, as ambient concentrations of Cu(2+) and Mn(2+) in precipitation and bark are known to limit the abundance of H. physodes, whereas limiting effects of Fe(2+) or Zn(2+) have never been found. This suggests that increasing the Cu(2+) and Mn(2+) tolerance stimulated the evolution of lichen substances in H. physodes. The depsidone physodalic acid is apparently most effective at reducing Cu(2+) and Mn(2+) uptake among the seven lichen substances produced by H. physodes. Probably lichen substances play a general role in the metal homeostasis of lichens.

  2. Lichen secondary metabolites are responsible for induction of apoptosis in HT-29 and A2780 human cancer cell lines.

    Science.gov (United States)

    Bačkorová, M; Jendželovský, R; Kello, M; Bačkor, M; Mikeš, J; Fedoročko, P

    2012-04-01

    Lichens are a known source of approximately 800 unique secondary metabolites, many of which play important ecological roles, including regulating the equilibrium between symbionts. However, only a few of these compounds have been assessed for their effectiveness against various in vitro cancer models. Moreover, the mechanisms of biological activity of lichen secondary metabolites on living cells (including cancer cells) are still almost entirely unknown. In the present study, we investigated the mechanisms of cytotoxicity of four lichen secondary metabolites (parietin, atranorin, usnic acid and gyrophoric acid) on A2780 and HT-29 cancer cell lines. We found that usnic acid and atranorin were more effective anti-cancer compounds when compared to parietin and gyrophoric acid. Usnic acid and atranorin were capable of inducing a massive loss in the mitochondrial membrane potential, along with caspase-3 activation (only in HT-29 cells) and phosphatidylserine externalization in both tested cell lines. Induction of both ROS and especially RNS may be responsible, at least in part, for the cytotoxic effects of the tested compounds. Based on the detection of protein expression (PARP, p53, Bcl-2/Bcl-xL, Bax, p38, pp38) we found that usnic acid and atranorin are activators of programmed cell death in A2780 and HT-29, probably through the mitochondrial pathway. Copyright © 2012 Elsevier Ltd. All rights reserved.

  3. Rod Porina (Porinaceae, lichenes) vo flore Kavkaza

    Czech Academy of Sciences Publication Activity Database

    Urbanavichus, G.; Vondrák, Jan; Urbanavichene, I.

    2017-01-01

    Roč. 102, č. 4 (2017), s. 563-576 ISSN 0006-8136 Institutional support: RVO:67985939 Keywords : lichens * distribution * Northern Caucasus Subject RIV: EF - Botanics OBOR OECD: Plant sciences, botany

  4. Lichen planus pigmetosus-like ashy dermatosis

    Directory of Open Access Journals (Sweden)

    Francesco Tripodi Cutrì

    2011-12-01

    Full Text Available Ashy dermatosis, also known as erythema dyschromicum perstans, is an idiopathic dermal melanosis of unknown etiology. We here describe an unusual case of 63-year-old Caucasian male with ashy dermatosis and skin lesion of lichen pigmentosus-like. No treatment was tried because the lesions were totally asymptomatic. After a control, three months later, all lesions had cleared up. This case is of interest because it proves the existence of ashy dermatosis with clinical aspect lichen planus pigmentosus-like. This is the first case in the literature of lichen planus pigmentosuslike ashy dermatosis confirming the view that ashy dermatosis is a variant of lichen planus without the typically band-like infiltrate and Max Joseph spaces.

  5. Impacts of Antibiotic and Bacteriophage Treatments on the Gut-Symbiont-Associated Blissus insularis (Hemiptera: Blissidae

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    Yao Xu

    2016-11-01

    Full Text Available The Southern chinch bug, Blissus insularis, possesses specialized midgut crypts that harbor dense populations of the exocellular symbiont Burkholderia. Oral administration of antibiotics suppressed the gut symbionts in B. insularis and negatively impacted insect host fitness, as reflected by retarded development, smaller body size, and higher susceptibility to an insecticide, bifenthrin. Considering that the antibiotics probably had non-lethal but toxic effects on host fitness, attempts were conducted to reduce gut symbionts using bacteriophage treatment. Soil-lytic phages active against the cultures of specific Burkholderia ribotypes were successfully isolated using a soil enrichment protocol. Characterization of the BiBurk16MC_R phage determined its specificity to the Bi16MC_R_vitro ribotype and placed it within the family Podoviridae. Oral administration of phages to fifth-instar B. insularis, inoculated with Bi16MC_R_vitro as neonates had no deleterious effects on host fitness. However, the ingested phages failed to impact the crypt-associated Burkholderia. The observed inactivity of the phage was likely due to the blockage of the connection between the anterior and posterior midgut regions. These findings suggest that the initial colonization by Burkholderia programs the ontogeny of the midgut, providing a sheltered residence protected from microbial antagonists.

  6. Earthworm symbiont Verminephrobacter eiseniae mediates natural transformation within the host egg capsules using type IV pili

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    SEANA Kelyn DAVIDSON

    2014-10-01

    Full Text Available The dense microbial communities commonly associated with plants and animals should offer many opportunities for horizontal gene transfer (HGT through described mechanisms of DNA exchange including natural transformation. However, studies of the significance of natural transformation have focused primarily on pathogens. The study presented here demonstrates highly efficient DNA exchange by natural transformation in a common symbiont of earthworms. The obligate bacterial symbiont Verminephrobacter eiseniae is a member of a microbial consortium of the earthworm Eisenia fetida that is transmitted into the egg capsules to colonize the embryonic worms. In the study presented here, by testing for transformants under different conditions in culture, we demonstrate that V. eiseniae can incorporate free DNA from the environment, that competency is regulated by environmental factors, and that it is sequence specific. Mutations in the type IV pili of V. eiseniae resulted in loss of DNA uptake, implicating the type IV pilus (TFP apparatus in DNA uptake. Furthermore, injection of DNA carrying antibiotic-resistance genes into egg capsules resulted in transformants within the capsule, demonstrating the relevance of DNA uptake within the earthworm system. The ability to take up species-specific DNA from the environment may explain the maintenance of the relatively large, intact genome of this long-associated obligate symbiont, and provides a mechanism for acquisition of foreign genes within the earthworm system.

  7. Monitoring lichen reinvasion of ameliorating environments

    Energy Technology Data Exchange (ETDEWEB)

    Henderson-Sellers, A; Seaward, M R.D.

    1979-01-01

    Bioindicators have not yet been widely used to measure the improving atmospheric conditions in our cities. This paper describes a study of the reinvasion of one lichen, Lecanora muralis (schreb.) rabenh., into the West Yorkshire conurbation. The results indicate that the response to improved atmospheric conditions is slow and difficult to model in terms of a simple threshold value of sulphur dioxide alone. It appears that the lichen's response becomes dependent upon other parameters as the atmospheric pollutant levels drop.

  8. Distribution of lichen flora on South Korea.

    Science.gov (United States)

    Hur, Jae-Seoun; Harada, Hiroshi; Oh, Soon-Ok; Lim, Kwang-Mi; Kang, Eui-Sung; Lee, Seung Mi; Kahng, Hyung-Yeel; Kim, Hyun-Woo; Jung, Jae-Sung; Koh, Young Jin

    2004-06-01

    After an overview on the temporary situation of the lichenology in South Korea, localities of 95 macrolichen taxa are reported for South Korea. In this revised lichen flora of South Korea, 16 species are apparently new to the territory. Voucher specimens have been deposited in the Korean Lichen Research Institute (KoLRI) at Sunchon National University in Korea, and duplicates have also been donated to the National History Museum and Institute, in Chiba, (CBM) Japan.

  9. Hidden Genetic Diversity in an Asexually Reproducing Lichen Forming Fungal Group.

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    Ruth Del-Prado

    Full Text Available Asexual species with vegetative propagation of both symbiont partners (soredia in lichens may harbor lower species diversity because they may indeed represent evolutionary dead ends or clones. In this study we aim to critically examine species boundaries in the sorediate lichen forming fungi Parmotrema reticulatum-Parmotrema pseudoreticulatum complex applying coalescent-based approaches and other recently developed DNA-based methods. To this end, we gathered 180 samples from Africa, Asia, Australasia, Europe, North and South America and generated sequences of internal transcribed spacer of nuclear ribosomal DNA (ITS and DNA replication licensing factor MCM7 (MCM7. The dataset was analysed using different approaches such as traditional phylogeny-maximum likelihood and Bayesian-genetic distances, automatic barcode gap discovery and coalescent-based methods-PTP, GMYC, spedeSTEM and *Beast-in order to test congruence among results. Additionally, the divergence times were also estimated to elucidate diversification events. Delimitations inferred from the different analyses are comparable with only minor differences, and following a conservative approach we propose that the sampled specimens of the P. reticulatum-P. pseudoreticulatum complex belong to at least eight distinct species-level lineages. Seven are currently classified under P. reticulatum and one as P. pseudoreticulatum. In this work we discuss one of only few examples of cryptic species that have so far been found in sorediate reproducing lichen forming fungi. Additionally our estimates suggest a recent origin of the species complex-during the Miocene. Consequently, the wide distribution of several of the cryptic species has to be explained by intercontinental long-distance dispersal events.

  10. Acetic Acid Bacteria as Symbionts of Insects

    KAUST Repository

    Crotti, Elena; Chouaia, Bessem; Alma, Alberto; Favia, Guido; Bandi, Claudio; Bourtzis, Kostas; Daffonchio, Daniele

    2016-01-01

    Acetic acid bacteria (AAB) are being increasingly described as associating with different insect species that rely on sugar-based diets. AAB have been found in several insect orders, among them Diptera, Hemiptera, and Hymenoptera, including several vectors of plant, animal, and human diseases. AAB have been shown to associate with the epithelia of different organs of the host, they are able to move within the insect’s body and to be transmitted horizontally and vertically. Here, we review the ecology of AAB and examine their relationships with different insect models including mosquitoes, leafhoppers, and honey bees. We also discuss the potential use of AAB in symbiont-based control strategies, such as “Trojan-horse” agents, to block the transmission of vector-borne diseases.

  11. Acetic Acid Bacteria as Symbionts of Insects

    KAUST Repository

    Crotti, Elena

    2016-06-14

    Acetic acid bacteria (AAB) are being increasingly described as associating with different insect species that rely on sugar-based diets. AAB have been found in several insect orders, among them Diptera, Hemiptera, and Hymenoptera, including several vectors of plant, animal, and human diseases. AAB have been shown to associate with the epithelia of different organs of the host, they are able to move within the insect’s body and to be transmitted horizontally and vertically. Here, we review the ecology of AAB and examine their relationships with different insect models including mosquitoes, leafhoppers, and honey bees. We also discuss the potential use of AAB in symbiont-based control strategies, such as “Trojan-horse” agents, to block the transmission of vector-borne diseases.

  12. Metabolic Profiling of Alpine and Ecuadorian Lichens

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    Verena K. Mittermeier

    2015-10-01

    Full Text Available Non-targeted 1H-NMR methods were used to determine metabolite profiles from crude extracts of Alpine and Ecuadorian lichens collected from their natural habitats. In control experiments, the robustness of metabolite detection and quantification was estimated using replicate measurements of Stereocaulon alpinum extracts. The deviations in the overall metabolite fingerprints were low when analyzing S. alpinum collections from different locations or during different annual and seasonal periods. In contrast, metabolite profiles observed from extracts of different Alpine and Ecuadorian lichens clearly revealed genus- and species-specific profiles. The discriminating functions determining cluster formation in principle component analysis (PCA were due to differences in the amounts of genus-specific compounds such as sticticin from the Sticta species, but also in the amounts of ubiquitous metabolites, such as sugar alcohols or trehalose. However, varying concentrations of these metabolites from the same lichen species e.g., due to different environmental conditions appeared of minor relevance for the overall cluster formation in PCA. The metabolic clusters matched phylogenetic analyses using nuclear ribosomal DNA (nrDNA internal transcribed spacer (ITS sequences of lichen mycobionts, as exemplified for the genus Sticta. It can be concluded that NMR-based non-targeted metabolic profiling is a useful tool in the chemo-taxonomy of lichens. The same approach could also facilitate the discovery of novel lichen metabolites on a rapid and systematical basis.

  13. The accumulation of metals in lichens

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    Smaranda Mâșu

    2017-05-01

    Full Text Available The capacity to accumulate metal in the lichen communities has been used to identify the level of air pollution due road traffic. Several analyses have been conducted in the study, on tissue from lichens collected from six areas: the park of a town, various sites on the town’s freeway and on a county road segment with moderate traffic. The analyzed lichens were from the Parmelia spp. species which grow naturally on trees found in borderline lanes of motorways. Based on the degree of heavy metal accumulation such as Cd, Cr, Cu, Fe Mn, Pb, Ni and Zn in the Parmelia spp. lichens, a correlation has been made, with the road traffic. According to the metal bioaccumulation degree in lichens tissue, it has been established that the sources such as traffic from the outskirts of cities, from the perimeter of gas stations and of county roads continuously spread products which contain these elements, into the atmosphere. The fast information regarding the quality of the air in the environment allows the use of lichens as organism which can indicate environmental conditions and their modification by accumulating substances.

  14. Lichens as indicators of radioactive contamination

    International Nuclear Information System (INIS)

    Biarzov, L.

    1993-01-01

    Samples of lichens were investigated, collected in 1987 in the Eastern Urals and in 1988 in the vicinity of Chernobyl. Data are given on the size of thalli of epiphytic lichens from trunks of pine in the Chernobyl area, and on the beta activity in epiphytic lichens in the birch forests of the Urals 30 years after the Kyshtym accident, as well as concentrations of 40 K, 106 Ru, 134 Cs, 137 Cs, and 144 Ce in lichen thalli and the bark of pine tree, taken at 5 locations in the vicinity of Chernobyl 1000 days after the accident. Also given are cross-ratios of radioactivity of 106 Ru, 134 Cs, 137 Cs, and 144 Ce in lichen thalli and in the bark of pine trees. The results indicate that the activity of radionuclides in lichen thalli make a fairly reliable indicator of relative differences between the investigated areas in terms of the level of surface contamination and qualitative composition of the involved radionuclides. (J.B.) 4 tabs., 15 refs

  15. FLORA LICHEN WESTERN MOUNTAINS VRANJE PLACE

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    Gordana Bogdanović

    2016-07-01

    Full Text Available Lichen is a symbiotic plant built by the cells of algae and fungi hyphae. Algae are usually presented - green (Chlorophyta or blue green (Cyanophyta, a mushroom commonly found is ascomycetae and sometimes basidiomycetae. Mushrooms receive oxygen and carbohydrates from algae, and they in turn provide water, CO2 and mineral salts. Lichens are often found on trees and rocks in unpolluted environments and can be used as a bioindicator species. In during 2015-2016. was realized a survey of epiphytic lichen flora of the western mountains in environment of Vranje. Sampling was carried out at 4 locations: Borino brdo, Krstilovica, Markovo Kale and Pljačkovica. Based on the collected and determined samples can be concluded that the study implemented of the area of 25 species of lichens of which: 8 as crust, leafy 12 and 5 shrub. The research results indicate that the lichen flora of the western mountains environments Vranje of a rich and diverse as a result of favorable geographic position, geological and soil composition, climate and plant cover that provide opportunities for the development and survival of lichens.

  16. Upregulation of angiogenesis in oral lichen planus.

    Science.gov (United States)

    Al-Hassiny, A; Friedlander, L T; Parachuru, V P B; Seo, B; Hussaini, H M; Rich, A M

    2018-02-01

    As angiogenesis is fundamental to the pathogenesis of many chronic inflammatory disorders, this study investigated the expression of various vascular markers in oral lichen planus and non-specific oral mucosal inflammatory tissues. Archival specimens of oral lichen planus (n = 15) and inflamed tissues (n = 13) were stained using immunohistochemistry with antibodies to CD34, vascular endothelial growth factor, vascular endothelial growth factor receptor and vasohibin. Nine representative sites at the epithelial-connective tissue junction and through the fibrous connective tissue were selected, and automated analysis techniques were used to determine the extent of positivity expressed as the percentage of positive cells. Significance was denoted when P lichen planus samples compared with inflamed controls. A higher level of CD34 was observed in the deeper parts of the connective tissue of Oral lichen planus (OLP) (P = .04), whereas VEGF and VEGFR2 expressions were higher all through the tissues (respectively, P lichen planus in all sites evaluated (P oral lichen planus compared with inflamed controls, with increased expression of pro-angiogenic factors and decreased anti-angiogenic expression. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  17. VEGFR-3 Expression in Oral Lichen Planus

    Science.gov (United States)

    Zolfaghari Saravi, Zahra; Seyedmajidi, Maryam; Sharbatdaran, Majid; Bijani, Ali; Mozaffari, Fatemeh; Aminishakib, Pouyan

    2017-02-01

    Background and objective: Given the postulated the role of inflammation and possible contribution of lymphangiogenesis in oral lichen planus, this study aimed to assess any associated presence of VEGFR-3. Material and Methods: This cross-sectional study was performed on 52 formalin fixed and paraffin embedded blocks of oral lichen planus (pathological diagnosis based on Modified WHO criteria), comprising 25 of erosive and 27 of reticular type, along with 60 samples of normal mucosa (with minimal inflammation from clinical and histopathological aspects) obtained at crown lengthening surgery. Four micron sections were cut from paraffin blocks and stained with H and E for confirmation of diagnosis and by immunohistochemistry with primary antibodies against VEGFR-3. Negative controls were provided by omission of primary antibody and placenta was considered as a positive control. Data were analyzed by Chi-square, Mann-Whitney and Kruskal-wallis tests and P lichen planus specimens and 5% of those from normal mucosa (poral lichen planus than in normal mucosa (poral lichen planus (p=0.262) and the average number of stained vessels (p=0.092) demonstrated no significant difference according to the type. Conclusion: It appears that VEGFR-3 expression might be involved in the pathogenesis of the oral lichen planus through increasing lymphatic vessels and lymphangiogenesis. Creative Commons Attribution License

  18. Lichens Lite?” chemical analysis of lichens for tracking 26 pollutants

    Science.gov (United States)

    Sarah Jovan; Susan Will-Wolf; Michael. Amacher

    2015-01-01

    Lichen chemistry can be used to estimate concentrations of environmental contaminants, ranging from heavy metals and fertilizers to polycyclic aromatic hydrocarbons, dioxins, pesticides, herbicides, and flame retardants. We conducted a pilot looking at 26 metals and nutrient anions in 5 widespread lichen species across the upper Midwest, including: As, Al, Ba, Ca, Cd,...

  19. Oxidoreductases and cellulases in lichens: possible roles in lichen biology and soil organic matter turnover.

    Science.gov (United States)

    Beckett, Richard P; Zavarzina, Anna G; Liers, Christiane

    2013-06-01

    Lichens are symbiotic associations of a fungus (usually an Ascomycete) with green algae and/or a cyanobacterium. They dominate on 8 % of the world's land surface, mainly in Arctic and Antarctic regions, tundra, high mountain elevations and as components of dryland crusts. In many ecosystems, lichens are the pioneers on the bare rock or soil following disturbance, presumably because of their tolerance to desiccation and high temperature. Lichens have long been recognized as agents of mineral weathering and fine-earth stabilization. Being dominant biomass producers in extreme environments they contribute to primary accumulation of soil organic matter. However, biochemical role of lichens in soil processes is unknown. Our recent research has demonstrated that Peltigeralean lichens contain redox enzymes which in free-living fungi participate in lignocellulose degradation and humification. Thus lichen enzymes may catalyse formation and degradation of soil organic matter, particularly in high-stress communities dominated by lower plants. In the present review we synthesize recently published data on lichen phenol oxidases, peroxidases, and cellulases and discuss their possible roles in lichen physiology and soil organic matter transformations. Copyright © 2013 The British Mycological Society. Published by Elsevier Ltd. All rights reserved.

  20. Lichen-derived compounds show potential for central nervous system therapeutics.

    Science.gov (United States)

    Reddy, R Gajendra; Veeraval, Lenin; Maitra, Swati; Chollet-Krugler, Marylène; Tomasi, Sophie; Dévéhat, Françoise Lohézic-Le; Boustie, Joël; Chakravarty, Sumana

    2016-11-15

    Natural products from lichens are widely investigated for their biological properties, yet their potential as central nervous system (CNS) therapeutic agents is less explored. The present study investigated the neuroactive properties of selected lichen compounds (atranorin, perlatolic acid, physodic acid and usnic acid), for their neurotrophic, neurogenic and acetylcholine esterase (AChE) activities. Neurotrophic activity (neurite outgrowth) was determined using murine neuroblastoma Neuro2A cells. A MTT assay was performed to assess the cytotoxicity of compounds at optimum neurotrophic activity. Neuro2A cells treated with neurotrophic lichen compounds were used for RT-PCR to evaluate the induction of genes that code for the neurotrophic markers BDNF and NGF. Immunoblotting was used to assess acetyl H3 and H4 levels, the epigenetic markers associated with neurotrophic and/or neurogenic activity. The neurogenic property of the compounds was determined using murine hippocampal primary cultures. AChE inhibition activity was performed using a modified Ellman's esterase method. Lichen compounds atranorin, perlatolic acid, physodic acid and (+)-usnic acid showed neurotrophic activity in a preliminary cell-based screening based on Neuro2A neurite outgrowth. Except for usnic acid, no cytotoxic effects were observed for the two depsides (atranorin and perlatolic acid) and the alkyl depsidone (physodic acid). Perlatolic acid appears to be promising, as it also exhibited AChE inhibition activity and potent proneurogenic activity. The neurotrophic lichen compounds (atranorin, perlatolic acid, physodic acid) modulated the gene expression of BDNF and NGF. In addition, perlatolic acid showed increased protein levels of acetyl H3 and H4 in Neuro2A cells. These lichen depsides and depsidones showed neuroactive properties in vitro (Neuro2A cells) and ex vivo (primary neural stem or progenitor cells), suggesting their potential to treat CNS disorders. Copyright © 2016 Elsevier Gmb

  1. Lichen flora and ecology of the roadside trees

    Energy Technology Data Exchange (ETDEWEB)

    Rydzak, J

    1972-01-01

    Investigations of the lichen flora of roadside trees were carried out at 69 sites in eastern Poland in 1966-1969. Conclusive relationships between lichen distributions and air pollution from automobile exhaust gases could not be inferred from the data.

  2. Potential alteration of precipitation chemistry by epiphytic lichens

    Energy Technology Data Exchange (ETDEWEB)

    Lang, G E; Reiners, W A; Heier, R K

    1976-01-01

    Epiphytic lichen growth is abundant on the boles and branches of balsam fir trees at high elevations in New Hampshire. These lichens absorb elements needed for growth from solutions flowing over their surfaces and from direct impaction of water droplets. This study describes how epiphytic lichens and fir needles altered the chemistry of simulated rain water solutions under laboratory conditions. Experiments showed: 1) lichens absorbed ammonium and nitrate from solution; the rate of uptake increased with increasing temperature of the solution, 2) lichens lost calcium, magnesium, and hydrogen to the solution, 3) lichen thalli also initially lost potassium, but in time, net movement was reversed back into the thallus, 4) cation movement increased with increasing temperature, and 5) fir needles responded in a manner similar to that of the lichens, but the amount of change was much less. From these results it seems that epiphytic lichens have potential ecological importance in altering the chemistry of throughfall and stemflow.

  3. Tracking transmission of apicomplexan symbionts in diverse Caribbean corals.

    Directory of Open Access Journals (Sweden)

    Nathan L Kirk

    Full Text Available Symbionts in each generation are transmitted to new host individuals either vertically (parent to offspring, horizontally (from exogenous sources, or a combination of both. Scleractinian corals make an excellent study system for understanding patterns of symbiont transmission since they harbor diverse symbionts and possess distinct reproductive modes of either internal brooding or external broadcast spawning that generally correlate with vertical or horizontal transmission, respectively. Here, we focused on the under-recognized, but apparently widespread, coral-associated apicomplexans (Protista: Alveolata to determine if symbiont transmission depends on host reproductive mode. Specifically, a PCR-based assay was utilized towards identifying whether planula larvae and reproductive adults from brooding and broadcast spawning scleractinian coral species in Florida and Belize harbored apicomplexan DNA. Nearly all (85.5%; n = 85/89 examined planulae of five brooding species (Porites astreoides, Agaricia tenuifolia, Agaricia agaricites, Favia fragum, Mycetophyllia ferox and adults of P. astreoides were positive for apicomplexan DNA. In contrast, no (n = 0/10 apicomplexan DNA was detected from planulae of four broadcast spawning species (Acropora cervicornis, Acropora palmata, Pseudodiploria strigosa, and Orbicella faveolata and rarely in gametes (8.9%; n = 5/56 of these species sampled from the same geographical range as the brooding species. In contrast, tissue samples from nearly all (92.0%; n = 81/88 adults of the broadcast spawning species A. cervicornis, A. palmata and O. faveolata harbored apicomplexan DNA, including colonies whose gametes and planulae tested negative for these symbionts. Taken together, these data suggest apicomplexans are transmitted vertically in these brooding scleractinian coral species while the broadcast spawning scleractinian species examined here acquire these symbionts horizontally. Notably, these transmission

  4. Tracking transmission of apicomplexan symbionts in diverse Caribbean corals.

    Science.gov (United States)

    Kirk, Nathan L; Ritson-Williams, Raphael; Coffroth, Mary Alice; Miller, Margaret W; Fogarty, Nicole D; Santos, Scott R

    2013-01-01

    Symbionts in each generation are transmitted to new host individuals either vertically (parent to offspring), horizontally (from exogenous sources), or a combination of both. Scleractinian corals make an excellent study system for understanding patterns of symbiont transmission since they harbor diverse symbionts and possess distinct reproductive modes of either internal brooding or external broadcast spawning that generally correlate with vertical or horizontal transmission, respectively. Here, we focused on the under-recognized, but apparently widespread, coral-associated apicomplexans (Protista: Alveolata) to determine if symbiont transmission depends on host reproductive mode. Specifically, a PCR-based assay was utilized towards identifying whether planula larvae and reproductive adults from brooding and broadcast spawning scleractinian coral species in Florida and Belize harbored apicomplexan DNA. Nearly all (85.5%; n = 85/89) examined planulae of five brooding species (Porites astreoides, Agaricia tenuifolia, Agaricia agaricites, Favia fragum, Mycetophyllia ferox) and adults of P. astreoides were positive for apicomplexan DNA. In contrast, no (n = 0/10) apicomplexan DNA was detected from planulae of four broadcast spawning species (Acropora cervicornis, Acropora palmata, Pseudodiploria strigosa, and Orbicella faveolata) and rarely in gametes (8.9%; n = 5/56) of these species sampled from the same geographical range as the brooding species. In contrast, tissue samples from nearly all (92.0%; n = 81/88) adults of the broadcast spawning species A. cervicornis, A. palmata and O. faveolata harbored apicomplexan DNA, including colonies whose gametes and planulae tested negative for these symbionts. Taken together, these data suggest apicomplexans are transmitted vertically in these brooding scleractinian coral species while the broadcast spawning scleractinian species examined here acquire these symbionts horizontally. Notably, these transmission patterns are

  5. Parasitic wasp responses to symbiont-based defense in aphids

    Directory of Open Access Journals (Sweden)

    Oliver Kerry M

    2012-02-01

    Full Text Available Abstract Background Recent findings indicate that several insect lineages receive protection against particular natural enemies through infection with heritable symbionts, but little is yet known about whether enemies are able to discriminate and respond to symbiont-based defense. The pea aphid, Acyrthosiphon pisum, receives protection against the parasitic wasp, Aphidius ervi, when infected with the bacterial symbiont Hamiltonella defensa and its associated bacteriophage APSE (Acyrthosiphon pisum secondary endosymbiont. Internally developing parasitoid wasps, such as A. ervi, use maternal and embryonic factors to create an environment suitable for developing wasps. If more than one parasitoid egg is deposited into a single aphid host (superparasitism, then additional complements of these factors may contribute to the successful development of the single parasitoid that emerges. Results We performed experiments to determine if superparasitism is a tactic allowing wasps to overcome symbiont-mediated defense. We found that the deposition of two eggs into symbiont-protected aphids significantly increased rates of successful parasitism relative to singly parasitized aphids. We then conducted behavioral assays to determine whether A. ervi selectively superparasitizes H. defensa-infected aphids. In choice tests, we found that A. ervi tends to deposit a single egg in uninfected aphids, but two or more eggs in H. defensa-infected aphids, indicating that oviposition choices may be largely determined by infection status. Finally, we identified differences in the quantity of the trans-β-farnesene, the major component of aphid alarm pheromone, between H. defensa-infected and uninfected aphids, which may form the basis for discrimination. Conclusions Here we show that the parasitic wasp A. ervi discriminates among symbiont-infected and uninfected aphids, and changes its oviposition behavior in a way that increases the likelihood of overcoming symbiont

  6. Symbiont modulates expression of specific gene categories in Angomonas deanei

    Directory of Open Access Journals (Sweden)

    Luciana Loureiro Penha

    Full Text Available Trypanosomatids are parasites that cause disease in humans, animals, and plants. Most are non-pathogenic and some harbor a symbiotic bacterium. Endosymbiosis is part of the evolutionary process of vital cell functions such as respiration and photosynthesis. Angomonas deanei is an example of a symbiont-containing trypanosomatid. In this paper, we sought to investigate how symbionts influence host cells by characterising and comparing the transcriptomes of the symbiont-containing A. deanei (wild type and the symbiont-free aposymbiotic strains. The comparison revealed that the presence of the symbiont modulates several differentially expressed genes. Empirical analysis of differential gene expression showed that 216 of the 7625 modulated genes were significantly changed. Finally, gene set enrichment analysis revealed that the largest categories of genes that downregulated in the absence of the symbiont were those involved in oxidation-reduction process, ATP hydrolysis coupled proton transport and glycolysis. In contrast, among the upregulated gene categories were those involved in proteolysis, microtubule-based movement, and cellular metabolic process. Our results provide valuable information for dissecting the mechanism of endosymbiosis in A. deanei.

  7. Bacterial Communities Associated with the Lichen Symbiosis▿ †

    Science.gov (United States)

    Bates, Scott T.; Cropsey, Garrett W. G.; Caporaso, J. Gregory; Knight, Rob; Fierer, Noah

    2011-01-01

    Lichens are commonly described as a mutualistic symbiosis between fungi and “algae” (Chlorophyta or Cyanobacteria); however, they also have internal bacterial communities. Recent research suggests that lichen-associated microbes are an integral component of lichen thalli and that the classical view of this symbiotic relationship should be expanded to include bacteria. However, we still have a limited understanding of the phylogenetic structure of these communities and their variability across lichen species. To address these knowledge gaps, we used bar-coded pyrosequencing to survey the bacterial communities associated with lichens. Bacterial sequences obtained from four lichen species at multiple locations on rock outcrops suggested that each lichen species harbored a distinct community and that all communities were dominated by Alphaproteobacteria. Across all samples, we recovered numerous bacterial phylotypes that were closely related to sequences isolated from lichens in prior investigations, including those from a lichen-associated Rhizobiales lineage (LAR1; putative N2 fixers). LAR1-related phylotypes were relatively abundant and were found in all four lichen species, and many sequences closely related to other known N2 fixers (e.g., Azospirillum, Bradyrhizobium, and Frankia) were recovered. Our findings confirm the presence of highly structured bacterial communities within lichens and provide additional evidence that these bacteria may serve distinct functional roles within lichen symbioses. PMID:21169444

  8. Treatment modalities of palmoplantar lichen planus: a brief review.

    Science.gov (United States)

    Feily, Amir; Yaghoobi, Reza; Nilforoushzadeh, Mohammad Ali

    2016-12-01

    Palmoplantar lichen planus is a localized and uncommon variant of lichen planus which is mostly resistant to treatment. Our purpose was to discuss all treatment modalities proposed and tested for palmoplantar lichen planus in the literature. A systematic review of the literature was conducted to evaluate evidence regarding all treatment modalities proposed and tested for palmoplantar lichen planus in the literature. Two major databases (PubMed, Google scholar) were searched. The review included all case reports, letters and original articles reporting any treatment for palmoplantar lichen planus but not treatment used in the other type of lichen planus, generalized lichen planus or other type of palmoplantar dermatoses. We have gone over more than 50 articles. There are many drugs that have been used in the treatment of lichen planus and generalized lichen planus but the palmoplantar type is a rare variety of lichen planus. That is why we could not find any clinical trial on the subject and just case reports have been described in this manuscript. In spite of plentiful investigations carried out on lichen planus, there is no treatment modality that has proved to be utterly satisfactory in treatment of palmoplantar lichen planus.

  9. A case with Lichen planus in the lines of Blaschko

    Directory of Open Access Journals (Sweden)

    Metehan Gençoğlu

    2011-12-01

    Full Text Available Lichen planus is an inflammatory disorder that may involveskin and mucous membranes. Linear lichen planusis a rare disorder occurring in approximately 0.2% of patientswith lichen planus. We report a case of linear lichenplanus on the upper extremity which lesions followed thelines of Blaschko. J Clin Exp Invest 2011; 2 (4: 430-432

  10. The lichens: general considerations. Role as pollution biological indicators

    International Nuclear Information System (INIS)

    Rivaux, E.

    1998-01-01

    After having recalled the morphology and the different classification of lichens, the author presents the main lichenous substances, in particular the depsides and the depsidones. A detailed study on the role of lichens as pollution biological indicators is given. (O.M.)

  11. Atmospheric deposition inputs and effects on lichen chemistry and indicator species in the Columbia River Gorge, USA

    International Nuclear Information System (INIS)

    Fenn, M.E.; Geiser, L.; Bachman, R.; Blubaugh, T.J.; Bytnerowicz, A.

    2007-01-01

    Topographic and meteorological conditions make the Columbia River Gorge (CRG) an 'exhaust pipe' for air pollutants generated by the Portland-Vancouver metropolis and Columbia Basin. We sampled fog, bulk precipitation, throughfall, airborne particulates, lichen thalli, and nitrophytic lichen distribution. Throughfall N and S deposition were high, 11.5-25.4 and 3.4-6.7 kg ha -1 over 4.5 months at all 9 and 4/9 sites, respectively. Deposition and lichen thallus N were highest at eastern- and western-most sites, implicating both agricultural and urban sources. Fog and precipitation pH were frequently as low as 3.7-5.0. Peak NO x , NH 3 , and SO 2 concentrations in the eastern CRG were low, suggesting enhanced N and S inputs were largely from particulate deposition. Lichens indicating nitrogen-enriched environments were abundant and lichen N and S concentrations were 2x higher in the CRG than surrounding national forests. The atmospheric deposition levels detected likely threaten Gorge ecosystems and cultural resources. - Nitrogen, sulfur and acidic deposition threaten natural and cultural resources in the Columbia River Gorge National Scenic Area

  12. Vulvovaginal-gingival Lichen Planus: Association with Lichen Planopilaris and Stratified Epithelium-specific Antinuclear Antibodies.

    Science.gov (United States)

    Olszewska, Malgorzata; Banka-Wrona, Agnieszka; Skrok, Anna; Rakowska, Adriana; Górska, Renata; Solomon, Lynn W; Rudnicka, Lidia

    2016-01-01

    Vulvovaginal-gingival lichen planus (VVG-LP) consists of a triad of symptoms: vulval, vaginal and gingival lichen planus lesions. The aim of this study was to analyse the prevalence of lesions in various anatomical locations in patients with VVG-LP. The study included 126 consecutive patients with lichen planus. Sixteen (12.7%) patients fulfilled the criteria of VVG-LP. In 12/16 (75%) patients with VVG-LP scalp lesions were also observed. Stratified epithelium-specific antinuclear antibodies (SES-ANA) and anti-ΔNp.3α antibodies were detected in 10/16 (75%) patients with VVG-LP and in 15/110 (13.6%) patients with other forms of lichen planus (p lichen planopilaris. The new entity may be termed "vulvovaginal-gingival-pilar lichen planus" and our study indicates that SES-ANA is a marker of this type of lichen planus with extensive, severe and refractory-to-therapy involvement of the mucous membranes, skin and scalp.

  13. A journey into the wild of the cnidarian model system Aiptasia and its symbionts

    KAUST Repository

    Voolstra, Christian R.

    2013-08-27

    The existence of coral reef ecosystems relies critically on the mutualistic relationship between calcifying cnidarians and photosynthetic, dinoflagellate endosymbionts in the genus Symbiodinium. Reef-corals have declined globally due to anthropogenic stressors, for example, rising sea-surface temperatures and pollution that often disrupt these symbiotic relationships (known as coral bleaching), exacerbating mass mortality and the spread of disease. This threatens one of the most biodiverse marine ecosystems providing habitats to millions of species and supporting an estimated 500 million people globally (Hoegh-Guldberg et al. 2007). Our understanding of cnidarian-dinoflagellate symbioses has improved notably with the recent application of genomic and transcriptomic tools (e.g. Voolstra et al. 2009; Bayer et al. 2012; Davy et al. 2012), but a model system that allows for easy manipulation in a laboratory environment is needed to decipher underlying cellular mechanisms important to the functioning of these symbioses. To this end, the sea anemone Aiptasia, otherwise known as a \\'pest\\' to aquarium hobbyists, is emerging as such a model system (Schoenberg & Trench 1980; Sunagawa et al. 2009; Lehnert et al. 2012). Aiptasia is easy to grow in culture and, in contrast to its stony relatives, can be maintained aposymbiotically (i.e. dinoflagellate free) with regular feeding. However, we lack basic information on the natural distribution and genetic diversity of these anemones and their endosymbiotic dinoflagellates. These data are essential for placing the significance of this model system into an ecological context. In this issue of Molecular Ecology, Thornhill et al. (2013) are the first to present genetic evidence on the global distribution, diversity and population structure of Aiptasia and its associated Symbiodinium spp. By integrating analyses of the host and symbiont, this research concludes that the current Aitpasia taxonomy probably needs revision and that two

  14. Oil hyphae of endolithic lichens and their fatty acid composition

    Energy Technology Data Exchange (ETDEWEB)

    Kushnir, E; Tietz, A; Galun, M

    1978-01-01

    The structure of medullary oil hyphae of twelve endolithic lichen species, belonging to different taxa and colonizing different habitats, was examined by light and electron microscopy. The chemical composition of lipids isolated from the oil hyphae and from two corresponding mycobionts grown in culture was determined. The oil hyphae of the various species appeared in different forms and contained large amounts of lipid in the form of oil globules. The hyphae of mycobionts isolated from two of the endoliths and grown in culture also contained large amounts of lipids. Triacylglycerol was the predominant lipid component in all the organisms examined. Hexadecanoic acid was the main saturated fatty acid; octadecenoic acid and octadecdienoic acid the predominant unsaturated fatty acids. Tetradecanoic, hexadecenoic, octadecanoic and octadectrienoic acids were also detected. The fatty acid distribution pattern appeared unaffected by the nature of substrate and climatic conditions. There is a certain similarity in the fatty acid composition in related species. 9 figures, 2 tables.

  15. The inadequacy of morphology for species and genus delineation in microbial eukaryotes: an example from the parabasalian termite symbiont coronympha.

    Directory of Open Access Journals (Sweden)

    James T Harper

    Full Text Available BACKGROUND: For the majority of microbial eukaryotes (protists, algae, there is no clearly superior species concept that is consistently applied. In the absence of a practical biological species concept, most species and genus level delineations have historically been based on morphology, which may lead to an underestimate of the diversity of microbial eukaryotes. Indeed, a growing body of molecular evidence, such as barcoding surveys, is beginning to support the conclusion that significant cryptic species diversity exists. This underestimate of diversity appears to be due to a combination of using morphology as the sole basis for assessing diversity and our inability to culture the vast majority of microbial life. Here we have used molecular markers to assess the species delineations in two related but morphologically distinct genera of uncultivated symbionts found in the hindgut of termites. METHODOLOGY/PRINCIPAL FINDINGS: Using single-cell isolation and environmental PCR, we have used a barcoding approach to characterize the diversity of Coronympha and Metacoronympha symbionts in four species of Incisitermes termites, which were also examined using scanning electron microscopy and light microcopy. Despite the fact that these genera are significantly different in morphological complexity and structural organisation, we find they are two life history stages of the same species. At the same time, we show that the symbionts from different termite hosts show an equal or greater level of sequence diversity than do the hosts, despite the fact that the symbionts are all classified as one species. CONCLUSIONS/SIGNIFICANCE: The morphological information used to describe the diversity of these microbial symbionts is misleading at both the genus and species levels, and led to an underestimate of species level diversity as well as an overestimate of genus level diversity. The genus 'Metacoronympha' is invalid and appears to be a life history stage of

  16. POTENSI LICHEN SEBAGAI SUMBER BAHAN OBAT: SUATU KAJIAN PUSTAKA

    Directory of Open Access Journals (Sweden)

    ERIS SEPTIANA

    2011-06-01

    Full Text Available Lichen is a plant with many benefits. Its abundant existence in an area may indicate that air pollution levels are still low. Besides as indicator of air quality, lichen is also used as traditional medicine. Until present time, application of lichens for arthritis, constipation, chemotherapy, external wound, microbial infection, worm and infestation are still done in some countries. It is due to active chemical compounds contain in lichen that has activities as antibacterial, antifungal, antiviral, antitumor, anticancer, antioxidant, anti-inflammatory, antiprotozoa, analgesic and antipyretic, and anthelmintic. With its potential and efforts to provide sustainable materials, lichen has good prospect to be developed become modern medicine.

  17. Radiocesium in lichens and reindeer

    International Nuclear Information System (INIS)

    Jones, B.

    1989-07-01

    More than 5000 reindeer were moved from highly contaminated winter pasture areas (20 - greater than 80 kBq/m 2 ) to less contaminated areas (1.3 - 2 kBq/m 2 ) with the aim to study the possibility to reduce radiocesium uptake in muscular tissue under practical management conditions. The initial body content of 137 Cs was about 12000 Bq/kg meat. After moving to the less contaminated area the radiocesium level decreased with an effective half-time of about 30 days to 3000 Bq/kg. A further decrease was seen in the summer when the animals mainly graze vascular plants with a higher fibre and potassium content than found in the winter diet. The transfer factor was calculated to 0.65 d/kg in winter and to 0.30 d/kg in summer grazing conditions. The potassium intake was calculated to 7 g/d on winter pasture with about 65% lichen intake and about 30 g/d on summer pasture with more than 65% vascular plant intake

  18. Plant growth promoting potential and phylogenetic characteristics of a lichenized nitrogen fixing bacterium, Enterobacter cloacae.

    Science.gov (United States)

    Swamy, Chidanandamurthy Thippeswamy; Gayathri, Devaraja; Devaraja, Thimmalapura Neelakantaiah; Bandekar, Mandar; D'Souza, Stecy Elvira; Meena, Ram Murti; Ramaiah, Nagappa

    2016-12-01

    Lichens are complex symbiotic association of mycobionts, photobionts, and bacteriobionts, including chemolithotropic bacteria. In the present study, 46 lichenized bacteria were isolated by conventional and enrichment culture methods on nitrogen-free bromothymol blue (NFb) medium. Only 11 of the 46 isolates fixed nitrogen on NFb and had reduced acetylene. All these 11 isolates had also produced siderophore and 10 of them the IAA. Further, ammonia production was recorded from nine of these nitrogen fixers (NF). On molecular characterization, 16 S rRNA sequencing recorded that, nine NF belonged to Proteobacteria, within Gammaproteobacteria, and were closely related to Enterobacter sp. with a maximum similarity to Enterobacter cloacae. Each one of our NF isolates was aligned closely to Enterobacter pulveris strain E443, Cronobacter sakazakii strain PNP8 and Providencia rettgeri strain ALK058. Notably, a few strains we examined found to possess plant growth promoting properties. This is the first report of Enterobacter sp. from lichens which may be inhabit lichen thalli extrinsically or intrinsically. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Treatment of Lichen Planus with Propranalol

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    K Pavithran

    1986-01-01

    Full Text Available Accidental observation of early cure of lichen planus in a female patient who received propranalol for the treatment of associated hyperthyroidism made us to try this drug in 20 patients with lichen planus. The cutaneous lesions responded very well to the treatment in 909′o of the cases. The mucous membrane lesions responded only partially and slowly. Another group of 20 patients with lichen planus who received only oral pheniramine maleate showed persistence of skin lesions even after 3 months. There were no serious side effects -with propranalol, though one patient with an atopic background, developed bronchial asthma for the first time at the age of 21. The excellent therapeutic response to propranalol-a beta-adrenergic receptor blocker, in these patients indicates further study.

  20. The uncultured luminous symbiont of Anomalops katoptron (Beryciformes: Anomalopidae) represents a new bacterial genus.

    Science.gov (United States)

    Hendry, Tory A; Dunlap, Paul V

    2011-12-01

    Flashlight fishes (Beryciformes: Anomalopidae) harbor luminous symbiotic bacteria in subocular light organs and use the bacterial light for predator avoidance, feeding, and communication. Despite many attempts anomalopid symbionts have not been brought into laboratory culture, which has restricted progress in understanding their phylogenetic relationships with other luminous bacteria, identification of the genes of their luminescence system, as well as the nature of their symbiotic interactions with their fish hosts. To begin addressing these issues, we used culture-independent analysis of the bacteria symbiotic with the anomalopid fish, Anomalops katoptron, to characterize the phylogeny of the bacteria and to identify the genes of their luminescence system including those involved in the regulation of luminescence. Analysis of the 16S rRNA, atpA, gapA, gyrB, pyrH, recA, rpoA, and topA genes resolved the A. katoptron symbionts as a clade nested within and deeply divergent from other members of Vibrionaceae. The bacterial luminescence (lux) genes were identified as a contiguous set (luxCDABEG), as found for the lux operons of other luminous bacteria. Phylogenetic analysis based on the lux genes confirmed the housekeeping gene phylogenetic placement. Furthermore, genes flanking the lux operon in the A. katoptron symbionts differed from those flanking lux operons of other genera of luminous bacteria. We therefore propose the candidate name Candidatus Photodesmus (Greek: photo = light, desmus = servant) katoptron for the species of bacteria symbiotic with A. katoptron. Results of a preliminary genomic analysis for genes regulating luminescence in other bacteria identified only a Vibrio harveyi-type luxR gene. These results suggest that expression of the luminescence system might be continuous in P. katoptron. Copyright © 2011 Elsevier Inc. All rights reserved.

  1. Estimation of lichen biomass with emphasis on reindeer winter pastures at Hardangervidda, S Norway

    OpenAIRE

    Arvid Odland; Sylvi M. Sandvik; Dag K. Bjerketvedt; Linn L. Myrvold

    2014-01-01

    Quantification of lichen abundance is important for management of reindeer populations. We measured dry lichen biomass in 876 micro plots (16.5 cm × 16.5 cm) systematically sampled within 219 vegetation plots (2 m × 2 m) from 7 different areas in S Norway. Lichen biomass was quantified as: (a) dry weight in g m-2, (b) lichen height in cm, (c) lichen cover, and (d) lichen volume (lichen height × lichen cover). Lichen biomass decreased with increasing precipitation and increasing altitude. On l...

  2. Substrates of Peltigera Lichens as a Potential Source of Cyanobionts.

    Science.gov (United States)

    Zúñiga, Catalina; Leiva, Diego; Carú, Margarita; Orlando, Julieta

    2017-10-01

    Photobiont availability is one of the main factors determining the success of the lichenization process. Although multiple sources of photobionts have been proposed, there is no substantial evidence confirming that the substrates on which lichens grow are one of them. In this work, we obtained cyanobacterial 16S ribosomal RNA gene sequences from the substrates underlying 186 terricolous Peltigera cyanolichens from localities in Southern Chile and maritime Antarctica and compared them with the sequences of the cyanobionts of these lichens, in order to determine if cyanobacteria potentially available for lichenization were present in the substrates. A phylogenetic analysis of the sequences showed that Nostoc phylotypes dominated the cyanobacterial communities of the substrates in all sites. Among them, an overlap was observed between the phylotypes of the lichen cyanobionts and those of the cyanobacteria present in their substrates, suggesting that they could be a possible source of lichen photobionts. Also, in most cases, higher Nostoc diversity was observed in the lichens than in the substrates from each site. A better understanding of cyanobacterial diversity in lichen substrates and their relatives in the lichens would bring insights into mycobiont selection and the distribution patterns of lichens, providing a background for hypothesis testing and theory development for future studies of the lichenization process.

  3. New records of Lichen-forming Fungi from Kenya | Kirika | Journal of ...

    African Journals Online (AJOL)

    Diversity of tropical lichen-forming fungi, especially crustose lichens is currently poorly known. Since lichens are important bioindicators of air pollution, forest health, and climate change, we addressed the lichen diversity in Kenya. Our study focused on the diversity of lichen-forming fungi in the Mount Kenya montane forests ...

  4. Quality or quantity: is nutrient transfer driven more by symbiont identity and productivity than by symbiont abundance?

    Science.gov (United States)

    Freeman, Christopher J; Thacker, Robert W; Baker, David M; Fogel, Marilyn L

    2013-06-01

    By forming symbiotic interactions with microbes, many animals and plants gain access to the products of novel metabolic pathways. We investigated the transfer of symbiont-derived carbon and nitrogen to the sponges Aplysina cauliformis, Aplysina fulva, Chondrilla caribensis, Neopetrosia subtriangularis and Xestospongia bocatorensis, all of which host abundant microbial populations, and Niphates erecta, which hosts a sparse symbiont community. We incubated sponges in light and dark bottles containing seawater spiked with (13)C- and (15)N-enriched inorganic compounds and then measured (13)C and (15)N enrichment in the microbial (nutrient assimilation) and sponge (nutrient transfer) fractions. Surprisingly, although most sponges hosting abundant microbial communities were more enriched in (13)C than N. erecta, only N. subtriangularis was more enriched in (15)N than N. erecta. Although photosymbiont abundance varied substantially across species, (13)C and (15)N enrichment was not significantly correlated with photosymbiont abundance. Enrichment was significantly correlated with the ratio of gross productivity to respiration (P:R), which varied across host species and symbiont phylotype. Because irradiance impacts P:R ratios, we also incubated A. cauliformis in (13)C-enriched seawater under different irradiances to determine whether symbiont carbon fixation and transfer are dependent on irradiance. Carbon fixation and transfer to the sponge host occurred in all treatments, but was greatest at higher irradiances and was significantly correlated with P:R ratios. Taken together, these results demonstrate that nutrient transfer from microbial symbionts to host sponges is influenced more by host-symbiont identities and P:R ratios than by symbiont abundance.

  5. Effects of gamma radiation on lichens and lichen-forming fungi and algae

    International Nuclear Information System (INIS)

    Erbisch, F.H.

    1977-06-01

    Initial literature reports indicated that lichens were highly resistant to gamma radiation. A series of experiments were undertaken to determine why lichens were so resistant. In experiments with Cladonia mitis, C. sylvatica, C. verticillata, Parmelia sulcata and P. subaurifera, using both acute and chronic radiation, it was found that these lichens were not highly resistant to gamma radiation. The lichens appeared to be resistant as long as they were in a dormant condition. But, when allowed to pass through a period which was suitable for growth, radiation damage was quickly manifested. Radiation damage was seen in various ways, including the change of thallus color, disintegration of phycobiant chloroplastids, coalescing of fungal hyphae, reduced CO 2 uptake, and reduction in thallus tensile strength

  6. How lichens impact on terrestrial community and ecosystem properties.

    Science.gov (United States)

    Asplund, Johan; Wardle, David A

    2017-08-01

    Lichens occur in most terrestrial ecosystems; they are often present as minor contributors, but in some forests, drylands and tundras they can make up most of the ground layer biomass. As such, lichens dominate approximately 8% of the Earth's land surface. Despite their potential importance in driving ecosystem biogeochemistry, the influence of lichens on community processes and ecosystem functioning have attracted relatively little attention. Here, we review the role of lichens in terrestrial ecosystems and draw attention to the important, but often overlooked role of lichens as determinants of ecological processes. We start by assessing characteristics that vary among lichens and that may be important in determining their ecological role; these include their growth form, the types of photobionts that they contain, their key functional traits, their water-holding capacity, their colour, and the levels of secondary compounds in their thalli. We then assess how these differences among lichens influence their impacts on ecosystem and community processes. As such, we consider the consequences of these differences for determining the impacts of lichens on ecosystem nutrient inputs and fluxes, on the loss of mass and nutrients during lichen thallus decomposition, and on the role of lichenivorous invertebrates in moderating decomposition. We then consider how differences among lichens impact on their interactions with consumer organisms that utilize lichen thalli, and that range in size from microfauna (for which the primary role of lichens is habitat provision) to large mammals (for which lichens are primarily a food source). We then address how differences among lichens impact on plants, through for example increasing nutrient inputs and availability during primary succession, and serving as a filter for plant seedling establishment. Finally we identify areas in need of further work for better understanding the role of lichens in terrestrial ecosystems. These include

  7. Antagonistic interactions between honey bee bacterial symbionts and implications for disease

    Directory of Open Access Journals (Sweden)

    Armstrong Tamieka-Nicole

    2006-03-01

    Full Text Available Abstract Background Honey bees, Apis mellifera, face many parasites and pathogens and consequently rely on a diverse set of individual and group-level defenses to prevent disease. One route by which honey bees and other insects might combat disease is through the shielding effects of their microbial symbionts. Bees carry a diverse assemblage of bacteria, very few of which appear to be pathogenic. Here we explore the inhibitory effects of these resident bacteria against the primary bacterial pathogen of honey bees, Paenibacillus larvae. Results Here we isolate, culture, and describe by 16S rRNA and protein-coding gene sequences 61 bacterial isolates from honey bee larvae, reflecting a total of 43 distinct bacterial taxa. We culture these bacteria alongside the primary larval pathogen of honey bees, Paenibacillus larvae, and show that many of these isolates severely inhibit the growth of this pathogen. Accordingly, symbiotic bacteria including those described here are plausible natural antagonists toward this widespread pathogen. Conclusion The results suggest a tradeoff in social insect colonies between the maintenance of potentially beneficial bacterial symbionts and deterrence at the individual and colony level of pathogenic species. They also provide a novel mechanism for recently described social components behind disease resistance in insect colonies, and point toward a potential control strategy for an important bee disease.

  8. Farming termites determine the genetic population structure of Termitomyces fungal symbionts

    DEFF Research Database (Denmark)

    Nobre, Tânia; Fernandes, Cecília; Boomsma, Jacobus J

    2011-01-01

    Symbiotic interactions between macrotermitine termites and their fungal symbionts have a moderate degree of specificity. Consistent with horizontal symbiont transmission, host switching has been frequent over evolutionary time so that single termite species can often be associated with several fu...

  9. Metagenomic Analysis of Microbial Symbionts in a Gutless Worm

    Energy Technology Data Exchange (ETDEWEB)

    Woyke, Tanja; Teeling, Hanno; Ivanova, Natalia N.; Hunteman, Marcel; Richter, Michael; Gloeckner, Frank Oliver; Boeffelli, Dario; Barry, Kerrie W.; Shapiro, Harris J.; Anderson, Iain J.; Szeto, Ernest; Kyrpides, Nikos C.; Mussmann, Marc; Amann, Rudolf; Bergin, Claudia; Ruehland, Caroline; Rubin, Edward M.; Dubilier, Nicole

    2006-05-01

    Symbioses between bacteria and eukaryotes are ubiquitous, yet our understanding of the interactions driving these associations is hampered by our inability to cultivate most host-associated microbes. Here we use a metagenomic approach to describe four co-occurring symbionts from the marine oligochaete Olavius algarvensis, a worm lacking a mouth, gut and nephridia. Shotgun sequencing and metabolic pathway reconstruction revealed that the symbionts are sulphur-oxidizing and sulphate-reducing bacteria, all of which are capable of carbon fixation, thus providing the host with multiple sources of nutrition. Molecular evidence for the uptake and recycling of worm waste products by the symbionts suggests how the worm could eliminate its excretory system, an adaptation unique among annelid worms. We propose a model that describes how the versatile metabolism within this symbiotic consortium provides the host with an optimal energy supply as it shuttles between the upper oxic and lower anoxic coastal sediments that it inhabits.

  10. Lichens of sub-Antarctic Heard Island

    NARCIS (Netherlands)

    Øvstedal, D.O.; Gremmen, N.J.M.

    2006-01-01

    A tota1 of 71 lichen species in 42 genera are listed for the island. Three species are described as new: “Arctomia” latispora Øvstedal, Fellhaneropsis subantarctica Øvstedal and Stereocaulon heardii Øvstedal. More than half of the species are restricted to the southern cold zone (Antarctica and

  11. Tropical urban lichens: observations from Singapore

    NARCIS (Netherlands)

    Sipman, H.J.M.

    2009-01-01

    The known lichen diversity of Singapore, 296 species, is comparable with temperate lowland areas, but the taxa involved are different, even at high taxonomic levels: the commonest orders are Arthoniales and Graphidales instead of Lecanorales. Epiphytic species dominate, while saxicolous and

  12. Lichen sclerosus en het syndroom van Turner

    NARCIS (Netherlands)

    van Ijsselmuiden, Mèlanie N; Bos, Annelies M E; Hoek, Annemieke; van Beek, André P; Kerstens, Michiel N

    2010-01-01

    Lichen sclerosus was diagnosed at a young age (19, 22 and 37 years) in three women with Turner syndrome. The oldest of these patients had probably suffered from this disorder for over 20 years. The relatively young age of these three patients is remarkable. This observation also suggests an

  13. Palmo-plantar lichen sclerosus et atrophicus

    Directory of Open Access Journals (Sweden)

    Aggarwal Kamal

    2003-01-01

    Full Text Available A case of lichen sclerosus et atrophicus (LSA in a male patient who presented with multiple hypopigmented to depigmented macules, polygonal in shape, distributed in a bilaterally, symmetrical manner over the hands, feet and flexor aspect of wrists is being reported. Histopathology confirmed the diagnosis of LSA.

  14. Coexistent vitiligo and actinic lichen planus

    Directory of Open Access Journals (Sweden)

    Ahmad Khalil

    1992-01-01

    Full Text Available A case of vitiligo who subsequently developed the lesions of lichen planus is described. Both types of lesions occurred on sun exposed areas, aggravated on photochemotherapy and showed improvement on para aminobenzoic acid cream application with avoidance of sun exposure. The possibility of common aetiological background is discussed.

  15. Antioxidant activity of lichen Cetraria aculeata

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    Tomović Jovica

    2016-01-01

    Full Text Available The aim of the present study is to investigate the antioxidant properties of the lichen Cetraria aculeata. Antioxidant activity of the methanol and ethyl acetate extracts of lichen was tested by different methods including determination of total phenolics content, determination of total antioxidant capacity, DPPH free radical scavenging activity, inhibitory activity towards lipid peroxidation, ferrous ion chelating ability and hydroxyl radical scavenging activity. The extracts of the lichen C. aculeata showed significant antioxidant activity. The methanol extract showed higher values for total phenolics and total antioxidant capacity compared to the ethyl acetate extract, while the ethyl acetate extract demonstrated better results for DPPH radical scavenging, inhibitory activity towards lipid peroxidation, chelating ability and hydroxyl radical scavenging than the methanol extract. This is the first report of the antioxidant properties of Cetraria aculeata growing in Serbia. The results of antioxidant activity indicate the application of this lichen as source of natural antioxidants that could be used as a possible food supplement, in the pharmaceutical industry and in the treatment of various diseases.

  16. Almost there: transmission routes of bacterial symbionts between trophic levels.

    Directory of Open Access Journals (Sweden)

    Elad Chiel

    Full Text Available Many intracellular microbial symbionts of arthropods are strictly vertically transmitted and manipulate their host's reproduction in ways that enhance their own transmission. Rare horizontal transmission events are nonetheless necessary for symbiont spread to novel host lineages. Horizontal transmission has been mostly inferred from phylogenetic studies but the mechanisms of spread are still largely a mystery. Here, we investigated transmission of two distantly related bacterial symbionts--Rickettsia and Hamiltonella--from their host, the sweet potato whitefly, Bemisia tabaci, to three species of whitefly parasitoids: Eretmocerus emiratus, Eretmocerus eremicus and Encarsia pergandiella. We also examined the potential for vertical transmission of these whitefly symbionts between parasitoid generations. Using florescence in situ hybridization (FISH and transmission electron microscopy we found that Rickettsia invades Eretmocerus larvae during development in a Rickettsia-infected host, persists in adults and in females, reaches the ovaries. However, Rickettsia does not appear to penetrate the oocytes, but instead is localized in the follicular epithelial cells only. Consequently, Rickettsia is not vertically transmitted in Eretmocerus wasps, a result supported by diagnostic polymerase chain reaction (PCR. In contrast, Rickettsia proved to be merely transient in the digestive tract of Encarsia and was excreted with the meconia before wasp pupation. Adults of all three parasitoid species frequently acquired Rickettsia via contact with infected whiteflies, most likely by feeding on the host hemolymph (host feeding, but the rate of infection declined sharply within a few days of wasps being removed from infected whiteflies. In contrast with Rickettsia, Hamiltonella did not establish in any of the parasitoids tested, and none of the parasitoids acquired Hamiltonella by host feeding. This study demonstrates potential routes and barriers to horizontal

  17. Metal homeostasis in Hypogymnia physodes is controlled by lichen substances

    International Nuclear Information System (INIS)

    Hauck, Markus

    2008-01-01

    The hypothesis was tested that the lichen substances produced by the epiphytic lichen Hypogymnia physodes control the intracellular uptake of divalent transition metals. Incubating lichen thalli with and without their natural content of lichen substances with metal solutions showed that the lichen substances of H. physodes selectively inhibit the uptake of Cu 2+ and Mn 2+ , but not of Fe 2+ and Zn 2+ . Such behavior is ecologically beneficial, as ambient concentrations of Cu 2+ and Mn 2+ in precipitation and bark are known to limit the abundance of H. physodes, whereas limiting effects of Fe 2+ or Zn 2+ have never been found. This suggests that increasing the Cu 2+ and Mn 2+ tolerance stimulated the evolution of lichen substances in H. physodes. The depsidone physodalic acid is apparently most effective at reducing Cu 2+ and Mn 2+ uptake among the seven lichen substances produced by H. physodes. Probably lichen substances play a general role in the metal homeostasis of lichens. - Lichen substances in Hypogymnia physodes specifically reduce the uptake of Cu 2+ and Mn 2+ , but not Fe 2+ or Zn 2+

  18. Occurrence patterns of lichens on stumps in young managed forests.

    Science.gov (United States)

    Svensson, Måns; Dahlberg, Anders; Ranius, Thomas; Thor, Göran

    2013-01-01

    The increasing demand for forest-derived bio-fuel may decrease the amount of dead wood and hence also the amount of available substrate for saproxylic ( = dead-wood dependent) organisms. Cut stumps constitute a large portion of dead wood in managed boreal forests. The lichen flora of such stumps has received little interest. Therefore, we investigated which lichens that occur on stumps in young (4-19 years), managed forests and analyzed how species richness and occurrence of individual species were related to stump and stand characteristics. We performed lichen inventories of 576 Norway spruce stumps in 48 forest stands in two study areas in Central Sweden, recording in total 77 lichen species. Of these, 14 were obligately lignicolous, while the remaining were generalists that also grow on bark, soil or rocks. We tested the effect of characteristics reflecting successional stage, microclimate, substrate patch size, and the species pool in the surrounding area on (1) total lichen species richness, (2) species richness of obligately lignicolous lichens and (3) the occurrence of four obligately lignicolous lichen species. The most important variables were stump age, with more species on old stumps, and study area, with similar total species richness but differences in occupancy for individual species. Responses for total lichen species richness and species richness of obligately lignicolous lichens were overall similar, indicating similar ecological requirements of these two groups. Our results indicate that species richness measurements serve as poor proxies for the responses of individual, obligately lignicolous lichen species.

  19. Occurrence patterns of lichens on stumps in young managed forests.

    Directory of Open Access Journals (Sweden)

    Måns Svensson

    Full Text Available The increasing demand for forest-derived bio-fuel may decrease the amount of dead wood and hence also the amount of available substrate for saproxylic ( = dead-wood dependent organisms. Cut stumps constitute a large portion of dead wood in managed boreal forests. The lichen flora of such stumps has received little interest. Therefore, we investigated which lichens that occur on stumps in young (4-19 years, managed forests and analyzed how species richness and occurrence of individual species were related to stump and stand characteristics. We performed lichen inventories of 576 Norway spruce stumps in 48 forest stands in two study areas in Central Sweden, recording in total 77 lichen species. Of these, 14 were obligately lignicolous, while the remaining were generalists that also grow on bark, soil or rocks. We tested the effect of characteristics reflecting successional stage, microclimate, substrate patch size, and the species pool in the surrounding area on (1 total lichen species richness, (2 species richness of obligately lignicolous lichens and (3 the occurrence of four obligately lignicolous lichen species. The most important variables were stump age, with more species on old stumps, and study area, with similar total species richness but differences in occupancy for individual species. Responses for total lichen species richness and species richness of obligately lignicolous lichens were overall similar, indicating similar ecological requirements of these two groups. Our results indicate that species richness measurements serve as poor proxies for the responses of individual, obligately lignicolous lichen species.

  20. Phylogenetic analysis of algal symbionts associated with four North American amphibian egg masses.

    Science.gov (United States)

    Kim, Eunsoo; Lin, Yuan; Kerney, Ryan; Blumenberg, Lili; Bishop, Cory

    2014-01-01

    Egg masses of the yellow-spotted salamander Ambystoma maculatum form an association with the green alga "Oophila amblystomatis" (Lambert ex Wille), which, in addition to growing within individual egg capsules, has recently been reported to invade embryonic tissues and cells. The binomial O. amblystomatis refers to the algae that occur in A. maculatum egg capsules, but it is unknown whether this population of symbionts constitutes one or several different algal taxa. Moreover, it is unknown whether egg masses across the geographic range of A. maculatum, or other amphibians, associate with one or multiple algal taxa. To address these questions, we conducted a phylogeographic study of algae sampled from egg capsules of A. maculatum, its allopatric congener A. gracile, and two frogs: Lithobates sylvatica and L. aurora. All of these North American amphibians form associations with algae in their egg capsules. We sampled algae from egg capsules of these four amphibians from localities across North America, established representative algal cultures, and amplified and sequenced a region of 18S rDNA for phylogenetic analysis. Our combined analysis shows that symbiotic algae found in egg masses of four North American amphibians are closely related to each other, and form a well-supported clade that also contains three strains of free-living chlamydomonads. We designate this group as the 'Oophila' clade, within which the symbiotic algae are further divided into four distinct subclades. Phylogenies of the host amphibians and their algal symbionts are only partially congruent, suggesting that host-switching and co-speciation both play roles in their associations. We also established conditions for isolating and rearing algal symbionts from amphibian egg capsules, which should facilitate further study of these egg mass specialist algae.

  1. Phylogenetic analysis of algal symbionts associated with four North American amphibian egg masses.

    Directory of Open Access Journals (Sweden)

    Eunsoo Kim

    Full Text Available Egg masses of the yellow-spotted salamander Ambystoma maculatum form an association with the green alga "Oophila amblystomatis" (Lambert ex Wille, which, in addition to growing within individual egg capsules, has recently been reported to invade embryonic tissues and cells. The binomial O. amblystomatis refers to the algae that occur in A. maculatum egg capsules, but it is unknown whether this population of symbionts constitutes one or several different algal taxa. Moreover, it is unknown whether egg masses across the geographic range of A. maculatum, or other amphibians, associate with one or multiple algal taxa. To address these questions, we conducted a phylogeographic study of algae sampled from egg capsules of A. maculatum, its allopatric congener A. gracile, and two frogs: Lithobates sylvatica and L. aurora. All of these North American amphibians form associations with algae in their egg capsules. We sampled algae from egg capsules of these four amphibians from localities across North America, established representative algal cultures, and amplified and sequenced a region of 18S rDNA for phylogenetic analysis. Our combined analysis shows that symbiotic algae found in egg masses of four North American amphibians are closely related to each other, and form a well-supported clade that also contains three strains of free-living chlamydomonads. We designate this group as the 'Oophila' clade, within which the symbiotic algae are further divided into four distinct subclades. Phylogenies of the host amphibians and their algal symbionts are only partially congruent, suggesting that host-switching and co-speciation both play roles in their associations. We also established conditions for isolating and rearing algal symbionts from amphibian egg capsules, which should facilitate further study of these egg mass specialist algae.

  2. Earthworm ecology affects the population structure of their Verminephrobacter symbionts

    DEFF Research Database (Denmark)

    Macedo Viana, Flavia Daniela; Jensen, Christopher Erik; Macey, Michael

    2016-01-01

    from two contrasting ecological types of earthworm hosts: the high population density, fast reproducing compost worms, Eisenia andrei and E. fetida, and the low-density, slow reproducing Aporrectodea tuberculata, commonly found in garden soils; for both types, three distinct populations were...... across host individuals from the same population. Thus, host ecology shapes the population structure of the Verminephrobacter symbionts. The homogeneous symbiont populations in the compost worms indicate that Verminephrobacter can be transferred bi-parentally or via leaky horizontal transmission in high...

  3. The symbiotic playground of lichen thalli--a highly flexible photobiont association in rock-inhabiting lichens.

    Science.gov (United States)

    Muggia, Lucia; Vancurova, Lucie; Škaloud, Pavel; Peksa, Ondrej; Wedin, Mats; Grube, Martin

    2013-08-01

    The development of characteristic thallus structures in lichen-forming fungi requires the association with suitable photoautotrophic partners. Previous work suggests that fungi have a specific range of compatible photobionts and that selected algal strains are also correlated with the habitat conditions. We selected the rock-inhabiting crust lichen Protoparmeliopsis muralis, which exhibits high flexibility in algal associations. We present a geographically extended and detailed analysis of algal association patterns including thalli which host superficial algal colonies. We sampled 17 localities in Europe, and investigated the photobiont genotypic diversity within and between thalli and compared the diversity of intrathalline photobionts and externally associate algal communities between washed and unwashed thalli by single-strand conformation polymorphism analyses and ITS sequence data. The results show that (1) photobiont population within the lichen thalli is homogeneous; (2) multiple photobiont genotypes occur within single areoles and lobes of individual lichens; and (3) algal communities which superficially colonize the lichen thalli host taxa known as photobionts in unrelated lichens. Photobiont association patterns are extremely flexible in this ecologically versatile crust-forming lichen. We suggest that lichen surfaces represent a potential temporary niche for free-living stages of lichen photobionts, which could facilitate the establishment of further lichens in the proximal area. © 2013 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

  4. Extremotolerance and resistance of lichens: comparative studies on five species used in astrobiological research II. Secondary lichen compounds.

    Science.gov (United States)

    Meessen, J; Sánchez, F J; Sadowsky, A; de la Torre, R; Ott, S; de Vera, J-P

    2013-12-01

    Lichens, which are symbioses of a fungus and one or two photoautotrophs, frequently tolerate extreme environmental conditions. This makes them valuable model systems in astrobiological research to fathom the limits and limitations of eukaryotic symbioses. Various studies demonstrated the high resistance of selected extremotolerant lichens towards extreme, non-terrestrial abiotic factors including space exposure, hypervelocity impact simulations as well as space and Martian parameter simulations. This study focusses on the diverse set of secondary lichen compounds (SLCs) that act as photo- and UVR-protective substances. Five lichen species used in present-day astrobiological research were compared: Buellia frigida, Circinaria gyrosa, Rhizocarpon geographicum, Xanthoria elegans, and Pleopsidium chlorophanum. Detailed investigation of secondary substances including photosynthetic pigments was performed for whole lichen thalli but also for axenically cultivated mycobionts and photobionts by methods of UV/VIS-spectrophotometry and two types of high performance liquid chromatography (HPLC). Additionally, a set of chemical tests is presented to confirm the formation of melanic compounds in lichen and mycobiont samples. All investigated lichens reveal various sets of SLCs, except C. gyrosa where only melanin was putatively identified. Such studies will help to assess the contribution of SLCs on lichen extremotolerance, to understand the adaptation of lichens to prevalent abiotic stressors of the respective habitat, and to form a basis for interpreting recent and future astrobiological experiments. As most of the identified SLCs demonstrated a high capacity in absorbing UVR, they may also explain the high resistance of lichens towards non-terrestrial UVR.

  5. Extremotolerance and Resistance of Lichens: Comparative Studies on Five Species Used in Astrobiological Research II. Secondary Lichen Compounds

    Science.gov (United States)

    Meeßen, J.; Sánchez, F. J.; Sadowsky, A.; de la Torre, R.; Ott, S.; de Vera, J.-P.

    2013-12-01

    Lichens, which are symbioses of a fungus and one or two photoautotrophs, frequently tolerate extreme environmental conditions. This makes them valuable model systems in astrobiological research to fathom the limits and limitations of eukaryotic symbioses. Various studies demonstrated the high resistance of selected extremotolerant lichens towards extreme, non-terrestrial abiotic factors including space exposure, hypervelocity impact simulations as well as space and Martian parameter simulations. This study focusses on the diverse set of secondary lichen compounds (SLCs) that act as photo- and UVR-protective substances. Five lichen species used in present-day astrobiological research were compared: Buellia frigida, Circinaria gyrosa, Rhizocarpon geographicum, Xanthoria elegans, and Pleopsidium chlorophanum. Detailed investigation of secondary substances including photosynthetic pigments was performed for whole lichen thalli but also for axenically cultivated mycobionts and photobionts by methods of UV/VIS-spectrophotometry and two types of high performance liquid chromatography (HPLC). Additionally, a set of chemical tests is presented to confirm the formation of melanic compounds in lichen and mycobiont samples. All investigated lichens reveal various sets of SLCs, except C. gyrosa where only melanin was putatively identified. Such studies will help to assess the contribution of SLCs on lichen extremotolerance, to understand the adaptation of lichens to prevalent abiotic stressors of the respective habitat, and to form a basis for interpreting recent and future astrobiological experiments. As most of the identified SLCs demonstrated a high capacity in absorbing UVR, they may also explain the high resistance of lichens towards non-terrestrial UVR.

  6. Lichen flora of London: effects of air pollution

    Energy Technology Data Exchange (ETDEWEB)

    Laundon, J R

    1967-01-01

    There is good, but not conclusive, evidence that sulfur dioxide is the pollutant which deleteriously affects lichens. The distribution of many lichens in London corresponds closely with the concentrations of sulfur dioxide. Low humidity is also a factor. Apart from actually killing lichens, increasing air pollution can render certain species incapable of colonizing new surfaces, although the old thalli themselves are able to survive as relicts. Until the early nineteenth century air pollution affected the lichen flora only in the small built-up area of London. The halting of building around London since 1938 has brought stability to the lichen vegetation of the area, and since then changes have been minor ones. Recent changes in pollution emissions have had little effect on the lichen flora between 1950 and 1967. This is to be expected as sulfur dioxide concentrations have remained fairly constant at ground level.

  7. Epiphytic lichens as indicators of environmental quality in Rome

    International Nuclear Information System (INIS)

    Munzi, S.; Ravera, S.; Caneva, G.

    2007-01-01

    A synthesis of the studies on lichen diversity carried out in Rome over the period 1982-2003 is presented. In this work, the Lichen Diversity (LD) method has been applied. Besides air pollution, the most important variable affecting the epiphytic lichen flora of Rome, currently updated to 102 taxa, is the influence of the Tyrrhenian Sea. Significant changes in the lichen flora have been noted over the past 20 years, with the lowest diversity now being found in the urban centre and in the eastern and southern sectors, while the 'lichen desert' area has decreased in parallel with decreasing concentrations of CO, NO x and SO 2. - Studies over the past 20 years have characterized the lichen diversity in the city of Rome

  8. Palmoplantar Lichen Planus: Dört olgu sunumu

    OpenAIRE

    Uçmak, Derya; Azizoğlu, Ruken; Harman, Mehmet

    2011-01-01

    Lichen planus is a benign, inflammatory and itchy dermatosis that is incurred by skin, skin extensions and mucosa. Lichen planus rarely show palmoplantar involvement. Since stratum corneum in palmoplantar lichen planus is extremely thick, lesions can be yellow colored instead of the purple colored papules that are classic lesions. Clinically, it might be confused with psoriasis, secondary syphilis, verruca vulgaris, hyperkeratotic eczema, palmoplantar keratodermas, hyperkeratotic type tinea p...

  9. A nuptially transmitted Ichthyosproean symbiont of Tenebrio molitor (Coleoptera: Tenebrionidae)

    Science.gov (United States)

    The yellow mealworm, Tenebrio molitor, harbors a symbiont that has spores with a thick, laminated wall and infects the fat body and ventral nerve chord of adult and larval beetles. In adult males, there is heavy infection of the epithelial cells of the testes and between testes lobes with occasional...

  10. Understanding nutrient exchange between Azolla and its symbiont, Nostoc

    OpenAIRE

    Eily, Ariana

    2017-01-01

    This is an in-depth look at the research I am doing for my doctoral degree at Duke University, investigating the exchange of nutrients between the aquatic fern genus, Azolla, and its cyanobacterial symbiont, Nostoc azollae. All of the illustrations and microscopy images within this presentation are my own.

  11. Complete Genome Sequence of the Human Gut Symbiont Roseburia hominis

    DEFF Research Database (Denmark)

    Travis, Anthony J.; Kelly, Denise; Flint, Harry J

    2015-01-01

    We report here the complete genome sequence of the human gut symbiont Roseburia hominis A2-183(T) (= DSM 16839(T) = NCIMB 14029(T)), isolated from human feces. The genome is represented by a 3,592,125-bp chromosome with 3,405 coding sequences. A number of potential functions contributing to host...

  12. Immunostimulatory effects of the phenolic compounds from lichens on nitric oxide and hydrogen peroxide production

    Directory of Open Access Journals (Sweden)

    Iracilda Z. Carlos

    Full Text Available The effects of isolated compounds from Brazilian lichens and their derivatives on H2O2 and NO production were studied using murine macrophages as a part of an attempt to understand their possible immunomodulatory properties. The compound cytotoxicity was studied using MTT assay. Macrophage stimulation was evaluated by the determination of NO (Griess assay and H2O2 (horseradish peroxidase/phenol red in supernatants of peritoneal macrophage cultures of Swiss mice. This research demonstrated stimulatory activities of some phenolic compounds isolated from lichens and their derivatives on H2O2 and NO production. Structure-activity relationships suggest several synthetic directions for further improvement of immunological activity.

  13. Lichens as biomonitors of uranium in the Balkan area

    International Nuclear Information System (INIS)

    Loppi, S.; Riccobono, F.; Zhang, Z.H.; Savic, S.; Ivanov, D.; Pirintsos, S.A.

    2003-01-01

    Widespread contamination by depleted uranium was not detected in the Balkan area. - The contribution of the conflict of 1999 to the environmental levels of uranium in the Balkan area was evaluated by means of lichens used as biomonitors. The average U concentration found in lichens in the present study was in line with the values reported for lichens from other countries and well below the levels found in lichens collected in areas with natural or anthropogenic sources of U. Measurement of isotopic ratios 235 U/ 238 U allowed to exclude the presence of depleted uranium. According to these results, we could not detect widespread environmental contamination by depleted uranium in the Balkan area

  14. Lichen secondary metabolites affect growth of Physcomitrella patens by allelopathy.

    Science.gov (United States)

    Goga, Michal; Antreich, Sebastian J; Bačkor, Martin; Weckwerth, Wolfram; Lang, Ingeborg

    2017-05-01

    Lichen secondary metabolites can function as allelochemicals and affect the development and growth of neighboring bryophytes, fungi, vascular plants, microorganisms, and even other lichens. Lichen overgrowth on bryophytes is frequently observed in nature even though mosses grow faster than lichens, but there is still little information on the interactions between lichens and bryophytes.In the present study, we used extracts from six lichen thalli containing secondary metabolites like usnic acid, protocetraric acid, atranorin, lecanoric acid, nortistic acid, and thamnolic acid. To observe the influence of these metabolites on bryophytes, the moss Physcomitrella patens was cultivated for 5 weeks under laboratory conditions and treated with lichen extracts. Toxicity of natural mixtures of secondary metabolites was tested at three selected doses (0.001, 0.01, and 0.1 %). When the mixture contained substantial amounts of usnic acid, we observed growth inhibition of protonemata and reduced development of gametophores. Significant differences in cell lengths and widths were also noticed. Furthermore, usnic acid had a strong effect on cell division in protonemata suggesting a strong impact on the early stages of bryophyte development by allelochemicals contained in the lichen secondary metabolites.Biological activities of lichen secondary metabolites were confirmed in several studies such as antiviral, antibacterial, antitumor, antiherbivore, antioxidant, antipyretic, and analgetic action or photoprotection. This work aimed to expand the knowledge on allelopathic effects on bryophyte growth.

  15. Surface Hydrophobicity Causes SO2 Tolerance in Lichens

    Science.gov (United States)

    Hauck, Markus; Jürgens, Sascha-René; Brinkmann, Martin; Herminghaus, Stephan

    2008-01-01

    Background and Aims The superhydrophobicity of the thallus surface in one of the most SO2-tolerant lichen species, Lecanora conizaeoides, suggests that surface hydrophobicity could be a general feature of lichen symbioses controlling their tolerance to SO2. The study described here tests this hypothesis. Methods Water droplets of the size of a raindrop were placed on the surface of air-dry thalli in 50 lichen species of known SO2 tolerance and contact angles were measured to quantify hydrophobicity. Key Results The wettability of lichen thalli ranges from strongly hydrophobic to strongly hydrophilic. SO2 tolerance of the studied lichen species increased with increasing hydrophobicity of the thallus surface. Extraction of extracellular lichen secondary metabolites with acetone reduced, but did not abolish the hydrophobicity of lichen thalli. Conclusions Surface hydrophobicity is the main factor controlling SO2 tolerance in lichens. It presumably originally evolved as an adaptation to wet habitats preventing the depression of net photosynthesis due to supersaturation of the thallus with water. Hydrophilicity of lichen thalli is an adaptation to dry or humid, but not directly rain-exposed habitats. The crucial role of surface hydrophobicity in SO2 also explains why many markedly SO2-tolerant species are additionally tolerant to other (chemically unrelated) toxic substances including heavy metals. PMID:18077467

  16. Fungal-associated NO is involved in the regulation of oxidative stress during rehydration in lichen symbiosis

    Directory of Open Access Journals (Sweden)

    Reig-Armiñana Jose

    2010-11-01

    Full Text Available Abstract Background Reactive oxygen species (ROS are normally produced in respiratory and photosynthetic electron chains and their production is enhanced during desiccation/rehydration. Nitric oxide (NO is a ubiquitous and multifaceted molecule involved in cell signaling and abiotic stress. Lichens are poikilohydrous organisms that can survive continuous cycles of desiccation and rehydration. Although the production of ROS and NO was recently demonstrated during lichen rehydration, the functions of these compounds are unknown. The aim of this study was to analyze the role of NO during rehydration of the lichen Ramalina farinacea (L. Ach., its isolated photobiont partner Trebouxia sp. and Asterochloris erici (Ahmadjian Skaloud et Peksa (SAG 32.85 = UTEX 911. Results Rehydration of R. farinacea caused the release of ROS and NO evidenced by the fluorescent probes DCFH2-DA and DAN respectively. However, a minimum in lipid peroxidation (MDA was observed 2 h post-rehydration. The inhibition of NO in lichen thalli with c-PTIO resulted in increases in both ROS production and lipid peroxidation, which now peaked at 3 h, together with decreases in chlorophyll autofluorescence and algal photobleaching upon confocal laser incidence. Trebouxia sp. photobionts generate peaks of NO-endproducts in suspension and show high rates of photobleaching and ROS production under NO inhibition which also caused a significant decrease in photosynthetic activity of A. erici axenic cultures, probably due to the higher levels of photo-oxidative stress. Conclusions Mycobiont derived NO has an important role in the regulation of oxidative stress and in the photo-oxidative protection of photobionts in lichen thalli. The results point to the importance of NO in the early stages of lichen rehydration.

  17. Interleukin-6 and neopterin levels in the serum and saliva of patients with Lichen planus and oral Lichen planus.

    Science.gov (United States)

    Abdel-Haq, Ayman; Kusnierz-Cabala, Beata; Darczuk, Dagmara; Sobuta, Eliza; Dumnicka, Paulina; Wojas-Pelc, Anna; Chomyszyn-Gajewska, Maria

    2014-11-01

    Lichen planus together with its oral variant is a chronic, inflammatory disease of the skin and the mucosa of unclear aetiology and with an unpredictable course that still poses a major problem in terms of diagnosis and treatment. The objective of this study was to assess the concentrations of interleukin-6 (IL-6) and neopterin in saliva and serum of patients with lichen planus (including reticular and erosive form of oral lichen planus) and to compare them with the concentrations observed in healthy controls. The study material comprised serum and saliva samples from 56 patients diagnosed with lichen planus and 56 healthy volunteers. The ELISA test was used to measure concentrations of IL-6 and neopterin in the serum and saliva of the study participants. The concentrations of IL-6 in saliva and serum of patients with lichen planus were significantly higher than in controls (P = 0.0002; P oral lichen planus had significantly higher IL-6 concentrations in their saliva compared to patients with reticular form of disease (P = 0.01). The concentrations of neopterin were significantly higher in the serum but not in saliva of lichen planus patients vs. controls (P lichen planus as well as the salivary concentrations of IL-6. The differences observed in IL-6 levels in patients with erosive-atrophic forms of oral lichen planus may indicate a substantial role played by the cytokine in the disease. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  18. Malignant Transformation of Oral Lichen Planus

    Directory of Open Access Journals (Sweden)

    Sangeeta Wanjari

    2010-01-01

    Full Text Available Oral lichen planus (OLP is a chronic inflammatory mucocutaneous disease that frequently involves the oral mucosa. It has been regarded by many authors as a premalignant condition. There has been a continuous debate regarding the possible malignant potential of OLP, and these patients have been recommended to have their lesions monitored two to four times annually. A case of a lichen planus transformed into malignancy is reported here. This case does not provide answers to the ongoing controversy about the innate propensity of OLP to become malignant. However, in view of common occurrence of OLP and unresolved issue regarding its malignant potential (MP, thus case report illustrates the need for histologic confirmation and close follow-up of patients with clinical lesions that have lichenoid features.

  19. Long-term consequences of disturbances on reproductive strategies of the rare epiphytic lichen Lobaria pulmonaria: clonality a gift and a curse.

    Science.gov (United States)

    Singh, Garima; Dal Grande, Francesco; Werth, Silke; Scheidegger, Christoph

    2015-01-01

    The effect of disturbance on symbiotic organisms such as lichens is particularly severe. In case of heterothallic lichen-forming fungi, disturbances may lead to unbalanced gene frequency and patchy distribution of mating types, thus inhibiting sexual reproduction and imposing clonality. The impact of disturbance on reproductive strategies and genetic diversity of clonal systems has so far received little attention. To infer the effects of disturbances on mating-type allele frequencies and population structure, we selected three populations in the Parc Jurassien Vaudois (Switzerland), which were affected by uneven-aged forestry, intensive logging and fire, respectively. We used microsatellite markers to infer genetic diversity, allelic richness and clonal diversity of the epiphytic lichen Lobaria pulmonaria and used L. pulmonaria-specific MAT1-1 and MAT1-2 markers to analyse the frequency and distribution of mating types of 889 individuals. Our study shows that stand-replacing disturbances affect the mating-type frequency and distribution, thus compromising the potential for sexual reproduction. The fire-disturbed area had a significantly lower genetic and genotypic diversity and a higher clonality. Furthermore, the majority of compatible mating pairs in this area were beyond the effective vegetative dispersal range of the species. We conclude that stand-replacing disturbances lead to lower chances of sex and symbiont reshuffling and thus have long-lasting negative consequences on the reproductive strategies and adaptive potential of epiphytic lichen symbioses. © FEMS 2014. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  20. Dapsone versus corticosteroids in lichen planus

    Directory of Open Access Journals (Sweden)

    Chopra Adarsh

    1999-01-01

    Full Text Available Seventy five patients with Lichen Planus (LP were enrolled from out-patient department for screening the therapeutic effect of dapsone. Patients were divided into two groups of 50 and 25. In regimen - 1 (RI 25 patients were given local corticosteroids and oral chlorpheniramine maleate. In regimen - 2 (R2 50 patients were given oral dapsone and chlorpheniramine maleate and topical coconut oil. It was found that total efficacy of R2 was 18% higher than R1.

  1. Aspects of the ecology of mat-forming lichens

    Directory of Open Access Journals (Sweden)

    P. D. Crittenden

    2000-03-01

    Full Text Available Lichen species in the genera Cladonia (subgenus Cladina, Cetraria, Stereocaulon and Alectoria are important vegetation components on well-drained terrain and on elevated micro-sites in peatlands in boreal-Arctic regions. These lichens often form closed mats, the component thalli in which grow vertically upwards at the apices and die off in the older basal regions; they are therefore only loosely attached to the underlying soil. This growth habit is relatively unusual in lichens being found in <0.5% of known species. It might facilitate internal nutrienr recycling and higher growth rates and, together with the production of allelochemicals, it might underlie the considerable ecological success of mat-forming lichens; experiments to critically assess the importance of these processes are required. Mat-forming lichens can constitute in excess of 60% of the winter food intake of caribou and reindeer. Accordingly there is a pressing need for data on lichen growth rates, measured as mass increment, in order to help determine the carrying capacity of winter ranges for rhese herbivores and to better predict recovery rates following grazing. Trampling during the snow-free season fragments lichen thalli; mat-forming lichens regenerate very successfully from thallus fragments provided trampling does nor re-occur. Frequent recurrence of trampling creates disturbed habitats from which lichens will rapidly become eliminated consistent with J.P. Grime's CSR strategy theory. Such damage to lichen ground cover has occurred where reindeer or caribou are unable to migrate away from their winter range such as on small islands or where political boundaries have been fenced; it can also occur on summer range that contains a significant lichen component and on winter range where numbers of migrarory animals become excessive. Species of Stereocaulon, and other genera that contain cyanobacteria (most notably Peltigera and Nephroma, are among the principal agents of

  2. [Lichen ruber planus : Better understanding, better treatment!

    Science.gov (United States)

    Schilling, L; Vogt, T

    2018-02-01

    Lichen ruber, also called lichen ruber planus or lichen planus (LP), is a noncontagious inflammatory skin disease. LP is the main representative and namesake of the group of lichenoid diseases, which are characterized by small papules often accompanied by severe itching. With 65% of cases, LP is primarily a disease of the mucous membranes. In 20% of the cases, the disease is found on the skin and mucous membranes; skin involvement alone is seen in only about 10% of cases. Cutaneous LP has a very favorable 1‑year prognosis of almost 80% healing as opposed to the mucosa and the adnexal organs. Histologically, keratinocytes with vacuolar degeneration, leaving behind apoptotic Kamino bodies and the characteristic band-shaped lymphocytic infiltrate at the dermatoepithelial junction, are common to lichenoid diseases. The horny layer is firm and compact and the stratum granulosum is thickened as a correlate of the Wickham stripes. The molecular pathogenesis, still partially hypothetical, assumes trigger factors leading to the presentation of intrinsic or foreign antigens. The triggered inflammation becomes independent in the sense of a classical cell-mediated autoimmune disease. Other autoimmune diseases are often associated with LP. Classical anti-inflammatory-immunosuppressive therapeutic concepts dominate with systemic retinoids ranking first in the highest evidence class for cutaneous LP with limitations in treatment of both mucosal and adnexal LP. More recently, interesting and new complementary phototherapeutics have been identified.

  3. Inheritance patterns of secondary symbionts during sexual reproduction of pea aphid biotypes.

    Science.gov (United States)

    Peccoud, Jean; Bonhomme, Joël; Mahéo, Frédérique; de la Huerta, Manon; Cosson, Olivier; Simon, Jean-Christophe

    2014-06-01

    Herbivorous insects frequently harbor bacterial symbionts that affect their ecology and evolution. Aphids host the obligatory endosymbiont Buchnera, which is required for reproduction, together with facultative symbionts whose frequencies vary across aphid populations. These maternally transmitted secondary symbionts have been particularly studied in the pea aphid, Acyrthosiphon pisum, which harbors at least 8 distinct bacterial species (not counting Buchnera) having environmentally dependent effects on host fitness. In particular, these symbiont species are associated with pea aphid populations feeding on specific plants. Although they are maternally inherited, these bacteria are occasionally transferred across insect lineages. One mechanism of such nonmaternal transfer is paternal transmission to the progeny during sexual reproduction. To date, transmission of secondary symbionts during sexual reproduction of aphids has been investigated in only a handful of aphid lineages and 3 symbiont species. To better characterize this process, we investigated inheritance patterns of 7 symbiont species during sexual reproduction of pea aphids through a crossing experiment involving 49 clones belonging to 9 host-specialized biotypes, and 117 crosses. Symbiont species in the progeny were detected with diagnostic qualitative PCR at the fundatrix stage hatching from eggs and in later parthenogenetic generations. We found no confirmed case of paternal transmission of symbionts to the progeny, and we observed that maternal transmission of a particular symbiont species (Serratia symbiotica) was quite inefficient. We discuss these observations in respect to the ecology of the pea aphid. © 2013 Institute of Zoology, Chinese Academy of Sciences.

  4. Relationship between epiphytic lichens, trace elements and gaseous atmospheric pollutants

    NARCIS (Netherlands)

    Dobben, van H.F.; Wamelink, G.W.W.; Braak, ter C.J.F.

    2001-01-01

    A study was conducted to determine the joint effect of gaseous atmospheric pollutants and trace elements on epiphytic lichens. We used our data to test the hypothesis that lichens are generally insensitive to toxic effects of trace elements, and can therefore be used as accumulator organisms to

  5. Using lichens as physiological indicators of sulfurous pollutants

    Energy Technology Data Exchange (ETDEWEB)

    Sundstroem, K R; Haellgren, J E

    1973-01-01

    Lichens are known to be extremely sensitive to sulfurous pollutants and have thus disappeared from the regions around urban areas. The authors give the physiological background to this sensitivity and an outline for a test system for sulfurous pollutants based on lichens.

  6. A hypothesis to explain lichen-Rangifer dynamic relationships

    Directory of Open Access Journals (Sweden)

    Eldar Gaare

    1997-04-01

    Full Text Available A small group of fruticous lichen species, viz. Cetraria nivalis, Cladonia mitis, C. stellaris, and Stereocaulon paschale forms extensive mats in the most winter habitats of Rangifer tarandus populations in Norway. The plant communities accessible for grazing are often found on easily drained, moraine ridges. These lichen species are perennial, lying on the ground while growing slowly at the top. As they decompose they add humus to the top of the soil profile. The lichen mats catch all water from small showers, thus preventing vascular plants from obtaining a more regular water supply. Grazing removs whole plants and gradually makes larger and larger holes in the lichen mats. Wind and water erode the humus, with only coarse gravel remaining. This diminishes the soil water storage capacity. Without grazing, lichens will gradually build a humus layer, which would improve the soil water storage capacity. In time vascular plants then would take the place of the lichens. I propose the hypothesis that by (over-grazing Rangifer improve their winter pastures by making conditions more favourable for lichens than for vascular plants.The fact that lichens are more scarce on habitats with more and regular precipitation, 1 in more oceanic climates, 2 on soils with more silt, and 3 on bird perches with thick peat due to regular fertilising, support this hypothesis.

  7. On the growth rate of the foliicolous lichen Strigula elegans

    NARCIS (Netherlands)

    Wilde-Duyfjes, de B.E.E.

    1967-01-01

    The diametral growth rate of the foliicolous lichen Strigula elegans (Fée) Müll. Arg., measured under natural conditions in the African tropical rainforest, has been established to amount to (0.7-)3-3-6(-8) mm annually. As compared to the diametral growth rate of lichens from temperate regions,

  8. Resolving genetic relationships in manna group of lichens from ...

    African Journals Online (AJOL)

    As in many lichen-forming fungi, species of Aspicilia genus are widely distributed all over the world, but no reports exist about their phylogenetic relations based on molecular biological methods. In the current study the phylogenetic relations of some Aspicilia species mainly manna group of lichens were investigated.

  9. Lichen habitat may be enhanced by thinning treatments

    Science.gov (United States)

    Heather T. Root; Bruce. McCune

    2013-01-01

    Epiphytic lichen communities have become a focus for ecologists concerned with forest health because lichens are particularly responsive to forest management and air quality. Furthermore, they can contribute substantially to the diversity and nitrogen fi xation of a stand, and play a valuable role in the food web of many forest-dwelling organisms. Can strategic...

  10. Chapter 7 - Climate effects on lichen indicators for nitrogen

    Science.gov (United States)

    Sarah Jovan

    2014-01-01

    The Lichen Communities Indicator is a sensitive indicator of forest health changes caused by air quality, climate change, and other stressors. To date, more than 8,000 epiphytic lichen surveys have been collected across the Nation by the Forest Inventory Analysis (FIA) and Forest Health Monitoring (FHM) Programs and their partners (table 7.1; Phelan and others 2012)....

  11. Responses of the lichen Ramalina menziesii Tayl. to ozone fumigations

    Science.gov (United States)

    J. Riddell; T.H. Nash; P. Padgett

    2010-01-01

    Tropospheric ozone (O3) is a strong oxidant, and is known to have serious negative effects on forest health. Lichens have bccn used as biomonitors of the effects of air pollution on forest health for sulfur and nitrogen pollutants. However, effects of O3 on lichens are not well understood, as past fumigation studies and...

  12. Acitretin for the management of generalized cutaneous lichen planus.

    Science.gov (United States)

    Vazirnia, Aria; Cohen, Philip R

    2014-09-16

    Lichen planus is an inflammatory disease that affects the skin, the oral mucosa, or both. Generalized cutaneous lichen planus may pose a therapeutic challenge for clinicians if the condition persists or flares after topical or systemic corticosteroid therapy. Acitretin, a systemic retinoid, can be considered a potential second-line treatment for patients with generalized cutaneous lichen planus. Herein, we describe a postmenopausal woman with generalized cutaneous lichen planus who was successfully treated with acitretin. A 58-year-old woman presented with generalized cutaneous lichen planus involving her upper and lower extremities as well as her lower back. After failing corticosteroid therapy, she was started on acitretin 20 mg/day, which was later increased to 30 mg/day. To review the literature on the use of acitretin in cutaneous lichen planus, we used the PubMed search engine and searched for the terms "acitretin" and "cutaneous lichen planus." Our patient had complete resolution of pruritus within one week of initiating acitretin 20 mg/day. After an increase in dose to 30 mg/day, the cutaneous lesions completely resolved over a 3-month period. There was no recurrence of disease as acitretin was tapered and discontinued. Generalized cutaneous lichen planus may pose a therapeutic challenge for the symptomatic relief of skin lesions. Topical and systemic corticosteroids are first-line treatments. In patients who fail corticosteroids, relapse after corticosteroid therapy, or have contraindications to corticosteroids, acitretin may be considered a potential second-line therapy.

  13. Bullous Lichen Planus in an Indian female | Puri | Sudanese Journal ...

    African Journals Online (AJOL)

    Bullous lichen planus is a rare entity. We describe bullous lichen planus in an. Indian female who had itchy erythematous papular lesions with vesicles and bullae predominantly over the dorsa of both legs. The patient was subjected to histopathological examination after which the diagnosis was confirmed. The patient was ...

  14. Antifungal activity of extracts from three species of lichens in Cuba

    International Nuclear Information System (INIS)

    Vaillant-Flores, Daymara Idonay; Romeu-Carballo, Carlos Rafael; Ramirez-Ochoa, Rebeca; Porras-Gonzalez, Angela; Gomez-Peralta, Marlene

    2015-01-01

    The antifungal activity of the three lichens extracts was evaluated in this work. Extracts from Leptogium cyanescens, Physcia americana and Pyxine aff. cocoes were collected extracts from the lichens thallus in 2009 in areas fromo the Jardin Botanico Cienfuego, Cuba. The fungicide activity was evaluated against phytopathogens fungi of potato: Rhizoctonia solani and Phytophthora nicotianae var parasitica. The study was conducted from 2009 to 2011. The compounds were extracted with acetone, concentrated by rotoevaporation, and evaluated at concentrated of 0,01 and 0,07% in potato dextrose agar (PDA) culture medium; stock solution was made of 5% dimethilsufoxide. These extracts were classified by their toxicity as: toxic, slight and moderately toxic and harmless. The extracts from P. americana of 0,07% inhibited P. nicotianae 100%, and it showed values over 50% for R. solani. L. cyanescens only showed fungicide activity in both phytopathogens at the maximum concentration studied; similar results were obtained with the extract from P. aff. cocoes. The lichens extracts were classified as lightly toxic at the maximun concentration, and harmless at the minimum concentration. (author) [es

  15. Luciferase genes cloned from the unculturable luminous bacteroid symbiont of the Caribbean flashlight fish, Kryptophanaron alfredi.

    Science.gov (United States)

    Haygood, M G; Cohn, D H

    1986-01-01

    Light organs of anomalopid (flashlight) fish contain luminous bacteroids that have never been cultured and, consequently, have been difficult to study. We have characterized the luciferase (lux) region of DNA extracted from light organs of the Caribbean flashlight fish Kryptophanaron alfredi by hybridization of cloned Vibrio harveyi lux genes to restriction-endonuclease-digested, light organ DNA. Comparison of the hybridization pattern of light organ DNA with that of DNA of a putative symbiotic isolate provides a method for identifying the authentic luminous symbiont regardless of its luminescence, and was used to reject one such isolate. Light organ DNA was further used to construct a cosmid clone bank and the luciferase genes were isolated. Unlike other bacterial luciferase genes, the genes were not expressed in Escherichia coli. When placed under the control of the E. coli trp promoter, the genes were transcribed but no luciferase was detected, suggesting a posttranscriptional block to expression.

  16. Bacterial cell motility of Burkholderia gut symbiont is required to colonize the insect gut.

    Science.gov (United States)

    Lee, Jun Beom; Byeon, Jin Hee; Jang, Ho Am; Kim, Jiyeun Kate; Yoo, Jin Wook; Kikuchi, Yoshitomo; Lee, Bok Luel

    2015-09-14

    We generated a Burkholderia mutant, which is deficient of an N-acetylmuramyl-l-alanine amidase, AmiC, involved in peptidoglycan degradation. When non-motile ΔamiC mutant Burkholderia cells harboring chain form were orally administered to Riptortus insects, ΔamiC mutant cells were unable to establish symbiotic association. But, ΔamiC mutant complemented with amiC gene restored in vivo symbiotic association. ΔamiC mutant cultured in minimal medium restored their motility with single-celled morphology. When ΔamiC mutant cells harboring single-celled morphology were administered to the host insect, this mutant established normal symbiotic association, suggesting that bacterial motility is essential for the successful symbiosis between host insect and Burkholderia symbiont. Copyright © 2015 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

  17. Contribution to the effects of air pollution on xerophyte lichens

    Energy Technology Data Exchange (ETDEWEB)

    Schubert, R; Fritsche, W

    1965-01-01

    Long-period investigations of the effects of gaseous air pollutants from a chemical plant on the respiration and thallus structure of three xerophyte lichens (Cladonia foliacea, Cladonia rangiformis, and Diploschistes bryophilus) are described. In a test series where the lichens were exposed to the polluted atmosphere in an urban area and near a chemical plant for over 12 months, Cladonia foliacea showed considerable decrease in the oxygen absorption, while the respiration of Cladonia rangiformis and Diploschistes bryophilus was affected slightly. The lichens, transferred from their natural site and exposed to emissions on the chemical plant premises for over 21 months, showed a negligible decrease in the oxygen absorption, nearly within the range of normal fluctuations. Microscopic investigations of the ashen gray lichens revealed severely damaged cellular structures and alga cells, as well as soot particles, especially in Diploschistes bryophilus. Remaining thalli showed, however, fairly active respiration, mostly due to the more-resistant lichen fungi. 7 references, 1 table.

  18. Fruticose lichen transplant technique for air pollution experiments

    Energy Technology Data Exchange (ETDEWEB)

    Kauppi, M

    1976-01-01

    Cladonia stellaris (Opiz) Pouz. and Vezta lichens were transplanted into small plastic containers and placed in the area surrounding a chemical factory and in built-up areas in Oulu, Northern Finland. The changes occasioned in the lichens by the effects of air pollution were determined under the microscope, by photography, by measuring their net assimilation rate (URAS-2), chlorophyll content, pH and electrical conductivity, and by various chemical analyses. The results obtained from two autumn series of experiments are presented here. The lichens reacted fairly sharply to pollutants in the air, in a manner reflecting the qualitative differences between the town environment and the fertilizer factory as sources of pollution. The technique described here is compared with transplants of corticolous lichens. It seems that fruticose lichens may be successfully used as pollution indicators provided that the exposure period is short; only a few months.

  19. Lichens as indicators of the ecological conditions of the habitat

    Energy Technology Data Exchange (ETDEWEB)

    Rydzak, J

    1968-01-01

    The susceptibility of lichens to changes in the urban environment make them good indicators of the intensity of air pollution. Studies covering a number of large and small towns, mostly in Europe and some over an extended time, explored the toxic influence of air pollution on 12 species on lichens. A comparison after 18 years with the lichen flora of Lublin, Poland found the lichen population impoverished. The toxic hypothesis, which blames increased coal consumption and automobile use, is inadequate to explain the condition. The drought hypothesis, which postulates that the occurrence and distribution of individual species is the result of a complex of numerous macro- and microclimatic, edaphic, geographical, historical, and other factors, gives a uniform view of the problem and stimulates investigations of the ecology of lichens in their natural habitat as well as in towns. 40 references, 12 figures, 3 tables.

  20. Lichens as biomonitors for radiocaesium following the Chernobyl accident

    International Nuclear Information System (INIS)

    Sloof, J.E.; Wolterbeek, B.Th.

    1992-01-01

    Caesium-137 resulting from the Chernobyl accident was monitored in lichens in The Netherlands. Caesium-137 activity in Parmelia sulcata ranged from 550 to 6100 (average 2500) Bq kg -1 dry weight. The similarity between the lichen data (geographical 137 Cs activity gradients and radioactivity values) and data of wet and dry deposition, indicate the validity of lichen monitoring of atmospheric 137 Cs. The ratio between the 137 Cs activity per unit lichen dry weight (kg) of Parmelia sulcata and the 137 Cs activity deposited per unit surface area (m 2 ) was approximately one. Measurements of 137 Cs accumulation in Xanthoria parietina show that the activity concentration could be expressed both on a dry weight and on a contour surface area basis. The determination of the biological half-life of 137 Cs in lichens was shown to be subject to sources of error such as growth and non-atmospheric/indirect 137 Cs influxes. (Author)

  1. A single phosphorus treatment doubles growth of cyanobacterial lichen transplants.

    Science.gov (United States)

    McCune, Bruce; Caldwell, Bruce A

    2009-02-01

    Lichens are reputedly slow growing and become unhealthy or die in response to supplements of the usual limiting resources, such as water and nitrogen. We found, however, that the tripartite cyanobacterial lichen Lobaria pulmonaria doubled in annual biomass growth after a single 20-minute immersion in a phosphorus solution (K2HPO4), as compared to controls receiving no supplemental phosphorus. This stimulation of cyanolichens by phosphorus has direct relevance to community and population ecology of lichens, including improving models of lichen performance in relation to air quality, improving forest management practices affecting old-growth associated cyanolichens, and understanding the distribution and abundance of cyanolichens on the landscape. Phosphorus may be as important a stimulant to cyanobacterial-rich lichen communities as it is to cyanobacteria in aquatic ecosystems.

  2. Cutaneous lichen planus: A systematic review of treatments.

    Science.gov (United States)

    Fazel, Nasim

    2015-06-01

    Various treatment modalities are available for cutaneous lichen planus. Pubmed, EMBASE, Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, Database of Abstracts of Reviews of Effects, and Health Technology Assessment Database were searched for all the systematic reviews and randomized controlled trials related to cutaneous lichen planus. Two systematic reviews and nine relevant randomized controlled trials were identified. Acitretin, griseofulvin, hydroxychloroquine and narrow band ultraviolet B are demonstrated to be effective in the treatment of cutaneous lichen planus. Sulfasalazine is effective, but has an unfavorable safety profile. KH1060, a vitamin D analogue, is not beneficial in the management of cutaneous lichen planus. Evidence from large scale randomized trials demonstrating the safety and efficacy for many other treatment modalities used to treat cutaneous lichen planus is simply not available.

  3. Surgical management of vulvovaginal agglutination due to lichen planus.

    Science.gov (United States)

    Fairchild, Pamela S; Haefner, Hope K

    2016-02-01

    Lichen planus is a rare dermatological disorder that is often associated with painful and disfiguring vulvovaginal effects. At the University of Michigan Center for Vulvar Diseases, we see many women with vulvovaginal lichen planus each year, with marked scarring and vulvovaginal agglutination that precludes vaginal intercourse and causes difficulty with urination. Through our experience, we developed a protocol for the operative management and postoperative care for severe vulvovaginal agglutination. Our objective is to share this protocol with a wider audience so that providers who see patients with these devastating effects of lichen planus can benefit from our experience to better serve this patient population. The figure represents a case of erosive lichen planus with early vaginal agglutination. The video reviews the pathophysiology and presentation of lichen planus. We then present a case of scarring and agglutination in a young woman, including our surgical management and postoperative care recommendations. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. A nuptially transmitted ichthyosporean symbiont of Tenebrio molitor (Coleoptera: Tenebrionidae).

    Science.gov (United States)

    Lord, Jeffrey C; Hartzer, Kris L; Kambhampati, Srinivas

    2012-01-01

    The yellow mealworm, Tenebrio molitor, harbors a symbiont that has spores with a thick, laminated wall and infects the fat body and ventral nerve chord of adult and larval beetles. In adult males, there is heavy infection of the epithelial cells of the testes and between testes lobes with occasional penetration of the lobes. Spores are enveloped in the spermatophores when they are formed at the time of mating and transferred to the female's bursa copulatrix. Infection has not been found in the ovaries. The sequence of the nuclear small subunit rDNA indicates that the symbiont is a member of the Ichthyosporea, a class of protists near the animal-fungi divergence. © 2012 The Author(s) Journal of Eukaryotic Microbiology © 2012 International Society of Protistologists.

  5. Comparative Genomic Analysis of Holospora spp., Intranuclear Symbionts of Paramecia

    Directory of Open Access Journals (Sweden)

    Sofya K. Garushyants

    2018-04-01

    Full Text Available While most endosymbiotic bacteria are transmitted only vertically, Holospora spp., an alphaproteobacterium from the Rickettsiales order, can desert its host and invade a new one. All bacteria from the genus Holospora are intranuclear symbionts of ciliates Paramecium spp. with strict species and nuclear specificity. Comparative metabolic reconstruction based on the newly sequenced genome of Holospora curviuscula, a macronuclear symbiont of Paramecium bursaria, and known genomes of other Holospora species shows that even though all Holospora spp. can persist outside the host, they cannot synthesize most of the essential small molecules, such as amino acids, and lack some central energy metabolic pathways, including glycolysis and the citric acid cycle. As the main energy source, Holospora spp. likely rely on nucleotides pirated from the host. Holospora-specific genes absent from other Rickettsiales are possibly involved in the lifestyle switch from the infectious to the reproductive form and in cell invasion.

  6. The Physiology of Microbial Symbionts in Fungus-Farming Termites

    DEFF Research Database (Denmark)

    Rodrigues da Costa, Rafael

    . The termites provide the fungus with optimal growth conditions (e.g., stable temperature and humidity), as well as with constant inoculation of growth substrate and protection against alien fungi. In reward, the fungus provides the termites with a protein-rich fungal biomass based diet. In addition...... with their symbionts are main decomposer of organic matter in Africa, and this is reflect of a metabolic complementarity to decompose plant biomass in the genome of the three organisms involved in this symbiosis. Many of the physiological aspects of this symbiosis remain obscure, and here I focus on physiology...... of microbial symbionts associated with fungus-growing termites. Firstly, by using a set of enzyme assays, plant biomass compositional analyses, and RNA sequencing we gained deeper understanding on what enzymes are produced and active at different times of the decomposition process. Our results show that enzyme...

  7. Host and Symbiont Jointly Control Gut Microbiota during Complete Metamorphosis

    Science.gov (United States)

    Johnston, Paul R.; Rolff, Jens

    2015-01-01

    Holometabolous insects undergo a radical anatomical re-organisation during metamorphosis. This poses a developmental challenge: the host must replace the larval gut but at the same time retain symbiotic gut microbes and avoid infection by opportunistic pathogens. By manipulating host immunity and bacterial competitive ability, we study how the host Galleria mellonella and the symbiotic bacterium Enterococcus mundtii interact to manage the composition of the microbiota during metamorphosis. Disenabling one or both symbiotic partners alters the composition of the gut microbiota, which incurs fitness costs: adult hosts with a gut microbiota dominated by pathogens such as Serratia and Staphylococcus die early. Our results reveal an interaction that guarantees the safe passage of the symbiont through metamorphosis and benefits the resulting adult host. Host-symbiont “conspiracies” as described here are almost certainly widespread in holometobolous insects including many disease vectors. PMID:26544881

  8. Symbiosis within Symbiosis: Evolving Nitrogen-Fixing Legume Symbionts.

    Science.gov (United States)

    Remigi, Philippe; Zhu, Jun; Young, J Peter W; Masson-Boivin, Catherine

    2016-01-01

    Bacterial accessory genes are genomic symbionts with an evolutionary history and future that is different from that of their hosts. Packages of accessory genes move from strain to strain and confer important adaptations, such as interaction with eukaryotes. The ability to fix nitrogen with legumes is a remarkable example of a complex trait spread by horizontal transfer of a few key symbiotic genes, converting soil bacteria into legume symbionts. Rhizobia belong to hundreds of species restricted to a dozen genera of the Alphaproteobacteria and Betaproteobacteria, suggesting infrequent successful transfer between genera but frequent successful transfer within genera. Here we review the genetic and environmental conditions and selective forces that have shaped evolution of this complex symbiotic trait. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Lichens as biomonitors with special reference to Antarctica

    International Nuclear Information System (INIS)

    Chipev, Nesho

    2002-01-01

    Lichens are effective biomonitors of metal deposition. Lichens are slow growing and assimilate metals at a rapid rate but release them at a low rate. Metal concentrations in lichen thalli have been shown to correlate with atmospheric levels. Lichens have been first used as bioaccumulative indicators in relation to point emission sources. Lichens have also been used to assess deposition patterns and heavy metal burdens for larger scale monitoring purposes. There are two problems to be kept in mind if lichens are to be effectively used as biomonitors. The first one is concerned with the chemical analyses. Results are more useful when background elemental levels are obtained. The choice of analytical method will depend on the purpose of the respective survey. Instrumental neutron activation analysis (INAA), atomic absorption spectrometry (AAS), Inductively coupled plasma emission spectrometry (ICP-ES) and epithermal neutron activation analysis (ENAA) are among the most commonly used methods. The second problem arises from the variability of lichens. Sources of variability include intra-individual variation, intra-species variation and variation due to microhabitat, locality or edaphic factors. Apart from individual variation, many of these sources of variation can be overcome by careful and thoughtful sampling and analysis of the selected species. Lichens and mosses are the only vegetation in Antarctica. The absence of air pollution in Antarctica suggests that lichens can be used as biomonitors of pollution at small scales around research bases. However, the unpolluted Antarctic environment presents opportunity for baseline studies on heavy metal bioaccumulation. Bioaccumulation in Antarctic lichens can allow a larger (global) scale insight into the airborne heavy metal circulation and deposition. Both high precision analytical methods and biological studies will be needed. (author)

  10. Deteriorating effects of lichen and microbial colonization of carbonate building rocks in the Romanesque churches of Segovia (Spain)

    International Nuclear Information System (INIS)

    Rios, Asuncion de los; Camara, Beatriz; Garcia del Cura, Ma Angeles; Rico, Victor J.; Galvan, Virginia; Ascaso, Carmen

    2009-01-01

    In this study, the deterioration effects of lichens and other lithobionts in a temperate mesothermal climate were explored. We examined samples of dolostone and limestone rocks with visible signs of biodeterioration taken from the exterior wall surfaces of four Romanesque churches in Segovia (Spain): San Lorenzo, San Martin, San Millan and La Vera Cruz. Biofilms developing on the lithic substrate were analyzed by scanning electron microscopy. The most common lichen species found in the samples were recorded. Fungal cultures were then obtained from these carbonate rocks and characterized by sequencing Internal Transcribed Spacers (ITS). Through scanning electron microscopy in back-scattered electron mode, fungi (lichenized and non-lichenized) were observed as the most frequent microorganisms occurring at sites showing signs of biodeterioration. The colonization process was especially conditioned by the porosity characteristics of the stone used in these buildings. While in dolostones, microorganisms mainly occupied spaces comprising the rock's intercrystalline porosity, in bioclastic dolomitized limestones, fungal colonization seemed to be more associated with moldic porosity. Microbial biofilms make close contact with the substrate, and thus probably cause significant deterioration of the underlying materials. We describe the different processes of stone alteration induced by fungal colonization and discuss the implications of these processes for the design of treatments to prevent biodeterioration

  11. Evaluation of antimicrobial activity of the lichens Physcia aipolia, Xanthoria parietina, Usnea florida, Usnea subfloridana and Melanohalea exasperata

    Directory of Open Access Journals (Sweden)

    Gülşah Çobanoğlu

    2016-06-01

    Full Text Available The present study aimed to evaluate the antimicrobial activity of methanol and chloroform extracts of five lichen species, Melanohalea exasperata, Physcia aipolia, Usnea florida, U. subfloridana and Xanthoria parietina. Antimicrobial activity in culture assays of these foliose and fruticose lichen extracts were examined against two Gram-negative bacteria (Pseudomonas aeruginosa and Escherichia coli, two Gram-positive bacteria (Enterococcus faecalis and Staphylococcus aureus, and the yeast Candida albicans using the paper disc method through determination of minimal inhibitory concentrations (MICs. The obtained results indicated the existence of different levels of antibiotic substances in the chloroform and the methanol extracts of the examined lichen species. The chloroform extracts of Usnea subfloridana showed the highest activity against Escherichia coli and Pseudomonas aeruginosa while the methanol extracts of this species were not active against these microorganisms. The chloroform extracts of the examined species exhibited more significant antimicrobial activity than the methanol extracts. None of the species were active against Enterococcus faecalis and Staphylococcus aureus. Most of the lichen extracts indicated a moderate antifungal activity against Candida albicans, except for Physcia aipolia, which was not active.

  12. Deteriorating effects of lichen and microbial colonization of carbonate building rocks in the Romanesque churches of Segovia (Spain)

    Energy Technology Data Exchange (ETDEWEB)

    Rios, Asuncion de los [Instituto de Recursos Naturales, Centro de Ciencias Medioambientales (CSIC), Serrano 115 dpdo., 28006 Madrid (Spain)], E-mail: arios@ccma.csic.es; Camara, Beatriz [Instituto de Recursos Naturales, Centro de Ciencias Medioambientales (CSIC), Serrano 115 dpdo., 28006 Madrid (Spain); Garcia del Cura, Ma Angeles [Instituto de Geologia Economica CSIC-UCM, Laboratorio de Petrologia Aplicada, Unidad Asociada CSIC-UA, Alicante (Spain); Rico, Victor J. [Departamento de Biologia Vegetal II, Facultad de Farmacia, Universidad Complutense, 28040 Madrid (Spain); Galvan, Virginia [Facultad Patrimonio Cultural, Universidad SEK, Convento de Santa Cruz la Real, 40003 Segovia (Spain); Ascaso, Carmen [Instituto de Recursos Naturales, Centro de Ciencias Medioambientales (CSIC), Serrano 115 dpdo., 28006 Madrid (Spain)

    2009-01-15

    In this study, the deterioration effects of lichens and other lithobionts in a temperate mesothermal climate were explored. We examined samples of dolostone and limestone rocks with visible signs of biodeterioration taken from the exterior wall surfaces of four Romanesque churches in Segovia (Spain): San Lorenzo, San Martin, San Millan and La Vera Cruz. Biofilms developing on the lithic substrate were analyzed by scanning electron microscopy. The most common lichen species found in the samples were recorded. Fungal cultures were then obtained from these carbonate rocks and characterized by sequencing Internal Transcribed Spacers (ITS). Through scanning electron microscopy in back-scattered electron mode, fungi (lichenized and non-lichenized) were observed as the most frequent microorganisms occurring at sites showing signs of biodeterioration. The colonization process was especially conditioned by the porosity characteristics of the stone used in these buildings. While in dolostones, microorganisms mainly occupied spaces comprising the rock's intercrystalline porosity, in bioclastic dolomitized limestones, fungal colonization seemed to be more associated with moldic porosity. Microbial biofilms make close contact with the substrate, and thus probably cause significant deterioration of the underlying materials. We describe the different processes of stone alteration induced by fungal colonization and discuss the implications of these processes for the design of treatments to prevent biodeterioration.

  13. Host-Polarized Cell Growth in Animal Symbionts.

    Science.gov (United States)

    Pende, Nika; Wang, Jinglan; Weber, Philipp M; Verheul, Jolanda; Kuru, Erkin; Rittmann, Simon K-M R; Leisch, Nikolaus; VanNieuwenhze, Michael S; Brun, Yves V; den Blaauwen, Tanneke; Bulgheresi, Silvia

    2018-04-02

    To determine the fundamentals of cell growth, we must extend cell biological studies to non-model organisms. Here, we investigated the growth modes of the only two rods known to widen instead of elongating, Candidatus Thiosymbion oneisti and Thiosymbion hypermnestrae. These bacteria are attached by one pole to the surface of their respective nematode hosts. By incubating live Ca. T. oneisti and T. hypermnestrae with a peptidoglycan metabolic probe, we observed that the insertion of new cell wall starts at the poles and proceeds inward, concomitantly with FtsZ-based membrane constriction. Remarkably, in Ca. T. hypermnestrae, the proximal, animal-attached pole grows before the distal, free pole, indicating that the peptidoglycan synthesis machinery is host oriented. Immunostaining of the symbionts with an antibody against the actin homolog MreB revealed that it was arranged medially-that is, parallel to the cell long axis-throughout the symbiont life cycle. Given that depolymerization of MreB abolished newly synthesized peptidoglycan insertion and impaired divisome assembly, we conclude that MreB function is required for symbiont widening and division. In conclusion, our data invoke a reassessment of the localization and function of the bacterial actin homolog. Copyright © 2018 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  14. A novel bacterial symbiont in the nematode Spirocerca lupi

    Directory of Open Access Journals (Sweden)

    Gottlieb Yuval

    2012-07-01

    Full Text Available Abstract Background The parasitic nematode Spirocerca lupi (Spirurida: Thelaziidae, the canine esophageal worm, is the causative agent of spirocercosis, a disease causing morbidity and mortality in dogs. Spirocerca lupi has a complex life cycle, involving an obligatory coleopteran intermediate host (vector, an optional paratenic host, and a definitive canid host. The diagnosis of spirocercosis is challenging, especially in the early disease stages, when adult worms and clinical signs are absent. Thus, alternative approaches are needed to promote early diagnosis. The interaction between nematodes and their bacterial symbionts has recently become a focus of novel treatment regimens for other helminthic diseases. Results Using 16S rDNA-based molecular methods, here we found a novel bacterial symbiont in S. lupi that is closely related to Comamonas species (Brukholderiales: Comamonadaceae of the beta-proteobacteria. Its DNA was detected in eggs, larvae and adult stages of S. lupi. Using fluorescent in situ hybridization technique, we localized Comamonas sp. to the gut epithelial cells of the nematode larvae. Specific PCR enabled the detection of this symbiont's DNA in blood obtained from dogs diagnosed with spirocercosis. Conclusions The discovery of a new Comamonas sp. in S. lupi increase the complexity of the interactions among the organisms involved in this system, and may open innovative approaches for diagnosis and control of spirocercosis in dogs.

  15. A novel extracellular gut symbiont in the marine worm Priapulus caudatus (Priapulida reveals an alphaproteobacterial symbiont clade of the Ecdysozoa

    Directory of Open Access Journals (Sweden)

    Paul eKroer

    2016-04-01

    Full Text Available Priapulus caudatus (phylum Priapulida is a benthic marine predatory worm with a cosmopolitan distribution. In its digestive tract we detected symbiotic bacteria that were consistently present in specimens collected over eight years from three sites at the Swedish west coast. Based on their 16S rRNA gene sequence, these symbionts comprise a novel genus of the order Rickettsiales (Alphaproteobacteria. Electron microscopy and fluorescence in situ hybridization (FISH identified them as extracellular, elongate bacteria closely associated with the microvilli, for which we propose the name ‘Candidatus Tenuibacter priapulorum’. Within Rickettsiales, they form a phylogenetically well-defined, family-level clade with uncultured symbionts of marine, terrestrial, and freshwater arthropods. Cand. Tenuibacter priapulorum expands the host range of this candidate family from Arthropoda to the entire Ecdysozoa, which may indicate an evolutionary adaptation of this bacterial group to the microvilli-lined guts of the Ecdysozoa.

  16. A Novel Extracellular Gut Symbiont in the Marine Worm Priapulus caudatus (Priapulida) Reveals an Alphaproteobacterial Symbiont Clade of the Ecdysozoa.

    Science.gov (United States)

    Kroer, Paul; Kjeldsen, Kasper U; Nyengaard, Jens R; Schramm, Andreas; Funch, Peter

    2016-01-01

    Priapulus caudatus (phylum Priapulida) is a benthic marine predatory worm with a cosmopolitan distribution. In its digestive tract we detected symbiotic bacteria that were consistently present in specimens collected over 8 years from three sites at the Swedish west coast. Based on their 16S rRNA gene sequence, these symbionts comprise a novel genus of the order Rickettsiales (Alphaproteobacteria). Electron microscopy and fluorescence in situ hybridization (FISH) identified them as extracellular, elongate bacteria closely associated with the microvilli, for which we propose the name "Candidatus Tenuibacter priapulorum". Within Rickettsiales, they form a phylogenetically well-defined, family-level clade with uncultured symbionts of marine, terrestrial, and freshwater arthropods. Cand. Tenuibacter priapulorum expands the host range of this candidate family from Arthropoda to the entire Ecdysozoa, which may indicate an evolutionary adaptation of this bacterial group to the microvilli-lined guts of the Ecdysozoa.

  17. Cellular tropism, population dynamics, host range and taxonomic status of an aphid secondary symbiont, SMLS (Sitobion miscanthi L type symbiont.

    Directory of Open Access Journals (Sweden)

    Tong Li

    Full Text Available SMLS (Sitobion miscanthi L type symbiont is a newly reported aphid secondary symbiont. Phylogenetic evidence from molecular markers indicates that SMLS belongs to the Rickettsiaceae and has a sibling relationship with Orientia tsutsugamushi. A comparative analysis of coxA nucleotide sequences further supports recognition of SMLS as a new genus in the Rickettsiaceae. In situ hybridization reveals that SMLS is housed in both sheath cells and secondary bacteriocytes and it is also detected in aphid hemolymph. The population dynamics of SMLS differ from those of Buchnera aphidicola and titer levels of SMLS increase in older aphids. A survey of 13 other aphids reveals that SMLS only occurs in wheat-associated species.

  18. Dissociation and metal-binding characteristics of yellow lichen substances suggest a relationship with site preferences of lichens.

    Science.gov (United States)

    Hauck, Markus; Jürgens, Sascha-René; Willenbruch, Karen; Huneck, Siegfried; Leuschner, Christoph

    2009-01-01

    Many species of lichen-forming fungi contain yellow or orange extracellular pigments belonging to the dibenzofurans (usnic acid), anthraquinones (e.g. parietin) or pulvinic acid group. These pigments are all equally efficient light screens, leading us to question the potential ecological and evolutionary significance of diversity in yellow and orange lichen substances. Here the hypothesis is tested that the different pigments differ in metal-binding characteristics, which suggest that they may contribute to adaptation to sites differing in pH and metal availability. UV spectroscopy was used to study the dissociation and the pH dependence of the metal-binding behaviour of seven isolated lichen substances in methanol. Metals applied were selected macro- and micro-nutrients (Cu(2+), Fe(2+), Fe(3+), Mg(2+), Mn(2+) and Zn(2+)). All the pigments studied are strong to moderate acids with pK(a1) values between 2.8 and 4.5. Metal complexation is common in the lichen substances studied. Complexation takes place under acidic conditions with usnic acid, but under alkaline conditions with parietin and most compounds of the pulvinic acid group. The pulvinic acid derivative rhizocarpic acid forms metal complexes both in the acidic and the alkaline range. Metal complexation by lichen substances could be a prerequisite for lichen substance-mediated control of metal uptake. Assuming such an effect at pH values where the affinity of the metal for the lichen substance is intermediate would explain the strong preference of lichens with usnic or rhizocarpic acids to acidic substrata. Moreover, it would explain the preference of lichens with parietin and some lichens with compounds of the pulvinic acid group either for nutrient-rich substrata at low pH or for calcareous substrata.

  19. A Process-based Model of Global Lichen Productivity

    Science.gov (United States)

    Porada, P.; Kleidon, A.

    2012-04-01

    Lichens and biotic crusts are abundant in most ecosystems of the world. They are the main autotrophic organisms in many deserts and at high altitudes and they can also be found in large amounts as epiphytes in some forests, especially in the boreal zone. They are characterised by a great variety of physiological properties, such as growth form, productivity or color. Due to the vast land surface areas covered by lichens, they may contribute significantly to the global terrestrial net carbon uptake. Furthermore, they potentially play an important role with respect to nutrient cycles in some ecosystems and they have the ability to enhance weathering at the surface on which they grow. A possible way to quantify these processes at the global scale is presented here in form of a process-based lichen model. This approach is based on the concepts used in many dynamical vegetation models and extends these methods to account for the specific properties of lichens. Hence, processes such as photosynthesis, respiration and water exchange are implemented as well as important trade-offs like photosynthetic capacity versus respiratory load and water content versus CO2 conductivity. The great physiological variability of lichens is incorporated directly into the model through ranges of possible parameter values, which are randomly sampled. In this way, many artificial lichen "species" are created and climate then acts as a filter to determine the species which are able to survive permanently. By averaging over the surviving "species", the model predicts lichen productivity as a function of climate input data such as temperature, radiation and precipitation at the global scale. Consequently, the contribution of lichens to the global carbon balance can be quantified. Moreover, global patterns of lichen biodiversity and other properties can be illustrated. The model can be extended to account for the nutrient dynamics of lichens, such as nitrogen fixation and the acquisition and

  20. Integrating microRNA and mRNA expression profiling in Symbiodinium microadriaticum, a dinoflagellate symbiont of reef-building corals.

    KAUST Repository

    Baumgarten, Sebastian; Bayer, Till; Aranda, Manuel; Liew, Yi Jin; Carr, Adrian; Micklem, Gos; Voolstra, Christian R.

    2013-01-01

    Animal and plant genomes produce numerous small RNAs (smRNAs) that regulate gene expression post-transcriptionally affecting metabolism, development, and epigenetic inheritance. In order to characterize the repertoire of endogenous smRNAs and potential gene targets in dinoflagellates, we conducted smRNA and mRNA expression profiling over 9 experimental treatments of cultures from Symbiodinium microadriaticum, a photosynthetic symbiont of scleractinian corals.

  1. Integrating microRNA and mRNA expression profiling in Symbiodinium microadriaticum, a dinoflagellate symbiont of reef-building corals.

    KAUST Repository

    Baumgarten, Sebastian

    2013-10-12

    Animal and plant genomes produce numerous small RNAs (smRNAs) that regulate gene expression post-transcriptionally affecting metabolism, development, and epigenetic inheritance. In order to characterize the repertoire of endogenous smRNAs and potential gene targets in dinoflagellates, we conducted smRNA and mRNA expression profiling over 9 experimental treatments of cultures from Symbiodinium microadriaticum, a photosynthetic symbiont of scleractinian corals.

  2. Diversity and Phylogenetic Analyses of Bacterial Symbionts in Three Whitefly Species from Southeast Europe

    OpenAIRE

    Skaljac, Marisa; Kanakala, Surapathrudu; Zanic, Katja; Puizina, Jasna; Lepen Pleic, Ivana; Ghanim, Murad

    2017-01-01

    Bemisia tabaci (Gennadius), Trialeurodes vaporariorum (Westwood), and Siphoninus phillyreae (Haliday) are whitefly species that harm agricultural crops in many regions of the world. These insects live in close association with bacterial symbionts that affect host fitness and adaptation to the environment. In the current study, we surveyed the infection of whitefly populations in Southeast Europe by various bacterial symbionts and performed phylogenetic analyses on the different symbionts dete...

  3. A Novel Extracellular Gut Symbiont in the Marine Worm Priapulus caudatus (Priapulida) Reveals an Alphaproteobacterial Symbiont Clade of the Ecdysozoa

    OpenAIRE

    Kroer, Paul; Kjeldsen, Kasper U.; Nyengaard, Jens R.; Schramm, Andreas; Funch, Peter

    2016-01-01

    Priapulus caudatus (phylum Priapulida) is a benthic marine predatory worm with a cosmopolitan distribution. In its digestive tract we detected symbiotic bacteria that were consistently present in specimens collected over eight years from three sites at the Swedish west coast. Based on their 16S rRNA gene sequence, these symbionts comprise a novel genus of the order Rickettsiales (Alphaproteobacteria). Electron microscopy and fluorescence in situ hybridization (FISH) identified them as extrace...

  4. Lichen planus pigmentosus: two atypical presentation

    Directory of Open Access Journals (Sweden)

    Falguni Nag

    2013-01-01

    Full Text Available Lichen planus pigmentosus (LPP is a chronic pigmentary disorder with variable pattern of presentation. We here by present two cases of LPP one with parallel band like pigmentation over abdomen sparing the abdominal skin creases and other with parallel band like pattern following the Blaschko’s lines over left side of the abdomen. Our cases are unique not only for its presentation but also for the pattern of distribution and LPP should be the differential diagnosis in any pigmentary disorders.

  5. Markers of Oral Lichen Planus Malignant Transformation

    Science.gov (United States)

    Tampa, Mircea; Mitran, Madalina; Mitran, Cristina; Matei, Clara; Georgescu, Simona-Roxana

    2018-01-01

    Oral lichen planus (OLP) is a chronic inflammatory disease of unknown etiology with significant impact on patients' quality of life. Malignant transformation into oral squamous cell carcinoma (OSCC) is considered as one of the most serious complications of the disease; nevertheless, controversy still persists. Various factors seem to be involved in the progression of malignant transformation; however, the mechanism of this process is not fully understood yet. Molecular alterations detected in OLP samples might represent useful biomarkers for predicting and monitoring the malignant progression. In this review, we discuss various studies which highlight different molecules as ominous predictors of OLP malignant transformation. PMID:29682099

  6. Aphid facultative symbionts reduce survival of the predatory lady beetle Hippodamia convergens

    Science.gov (United States)

    2014-01-01

    Background Non-essential facultative endosymbionts can provide their hosts with protection from parasites, pathogens, and predators. For example, two facultative bacterial symbionts of the pea aphid (Acyrthosiphon pisum), Serratia symbiotica and Hamiltonella defensa, protect their hosts from parasitism by two species of parasitoid wasp. Previous studies have not explored whether facultative symbionts also play a defensive role against predation in this system. We tested whether feeding on aphids harboring different facultative symbionts affected the fitness of an aphid predator, the lady beetle Hippodamia convergens. Results While these aphid faculative symbionts did not deter lady beetle feeding, they did decrease survival of lady beetle larvae. Lady beetle larvae fed a diet of aphids with facultative symbionts had significantly reduced survival from egg hatching to pupation and therefore had reduced survival to adult emergence. Additionally, lady beetle adults fed aphids with facultative symbionts were significantly heavier than those fed facultative symbiont-free aphids, though development time was not significantly different. Conclusions Aphids reproduce clonally and are often found in large groups. Thus, aphid symbionts, by reducing the fitness of the aphid predator H. convergens, may indirectly defend their hosts’ clonal descendants against predation. These findings highlight the often far-reaching effects that symbionts can have in ecological systems. PMID:24555501

  7. Identification of Spiroplasma insolitum symbionts in Anopheles gambiae [version 1; referees: 2 approved, 1 not approved

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    Sharon T. Chepkemoi

    2017-09-01

    Full Text Available Background: Insect symbionts have the potential to block the transmission of vector-borne diseases by their hosts. The advancement of a symbiont-based transmission blocking strategy for malaria requires the identification and study of Anopheles symbionts. Methods: High throughput 16S amplicon sequencing was used to profile the bacteria associated with Anopheles gambiae sensu lato and identify potential symbionts. The polymerase chain reaction (PCR with specific primers were subsequently used to monitor symbiont prevalence in field populations, as well as symbiont transmission patterns. Results: We report the discovery of the bacterial symbiont, Spiroplasma, in Anopheles gambiae in Kenya. We determine that geographically dispersed Anopheles gambiae populations in Kenya are infected with Spiroplasma at low prevalence levels. Molecular phylogenetics indicates that this Anopheles gambiae associated Spiroplasma is a member of the insolitum clade. We demonstrate that this symbiont is stably maternally transmitted across at least two generations and does not significantly affect the fecundity or egg to adult survival of its host. Conclusions: In diverse insect species, Spiroplasma has been found to render their host resistant to infection by pathogens. The identification of a maternally transmitted strain of Spiroplasma in Anopheles gambiae may therefore open new lines of investigation for the development of symbiont-based strategies for blocking malaria transmission.

  8. A Novel, Extremely Elongated, and Endocellular Bacterial Symbiont Supports Cuticle Formation of a Grain Pest Beetle.

    Science.gov (United States)

    Hirota, Bin; Okude, Genta; Anbutsu, Hisashi; Futahashi, Ryo; Moriyama, Minoru; Meng, Xian-Ying; Nikoh, Naruo; Koga, Ryuichi; Fukatsu, Takema

    2017-09-26

    The saw-toothed grain beetle, Oryzaephilus surinamensis (Silvanidae), is a cosmopolitan stored-product pest. Early studies on O. surinamensis in the 1930s described the presence of peculiar bacteriomes harboring endosymbiotic bacteria in the abdomen. Since then, however, the microbiological nature of the symbiont has been elusive. Here we investigated the endosymbiotic system of O. surinamensis in detail. In the abdomen of adults, pupae, and larvae, four oval bacteriomes were consistently identified, whose cytoplasm was full of extremely elongated tubular bacterial cells several micrometers wide and several hundred micrometers long. Molecular phylogenetic analysis identified the symbiont as a member of the Bacteroidetes , in which the symbiont was the most closely related to the endosymbiont of a grain pest beetle, Rhyzopertha dominica (Bostrichidae). The symbiont was detected in developing embryos, corroborating vertical symbiont transmission through host generations. The symbiont gene showed AT-biased nucleotide composition and accelerated molecular evolution, plausibly reflecting degenerative evolution of the symbiont genome. When the symbiont infection was experimentally removed, the aposymbiotic insects grew and reproduced normally, but exhibited a slightly but significantly more reddish cuticle and lighter body mass. These results indicate that the symbiont of O. surinamensis is not essential for the host's growth and reproduction but contributes to the host's cuticle formation. Symbiont genome sequencing and detailed comparison of fitness parameters between symbiotic and aposymbiotic insects under various environmental conditions will provide further insights into the symbiont's biological roles for the stored-product pest. IMPORTANCE Some beetles notorious as stored-product pests possess well-developed symbiotic organs called bacteriomes for harboring specific symbiotic bacteria, although their biological roles have been poorly understood. Here we report

  9. Aphid secondary symbionts do not affect prey attractiveness to two species of predatory lady beetles.

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    Jennifer L Kovacs

    Full Text Available Heritable symbionts have been found to mediate interactions between host species and their natural enemies in a variety of organisms. Aphids, their facultative symbionts, and their potential fitness effects have been particularly well-studied. For example, the aphid facultative symbiont Regiella can protect its host from infection from a fungal pathogen, and aphids with Hamiltonella are less likely to be parasitized by parasitic wasps. Recent work has also found there to be negative fitness effects for the larvae of two species of aphidophagous lady beetles that consumed aphids with facultative symbionts. In both species, larvae that consumed aphids with secondary symbionts were significantly less likely to survive to adulthood. In this study we tested whether adult Harmonia axyridis and Hippodamia convergens lady beetles avoided aphids with symbionts in a series of choice experiments. Adults of both lady beetle species were as likely to choose aphids with symbionts as those without, despite the potential negative fitness effects associated with consuming aphids with facultative symbionts. This may suggest that under natural conditions aphid secondary symbionts are not a significant source of selection for predatory lady beetles.

  10. Strawberry farming with lichens: an alternative to the environment | Cultivo de morangos com líquens: uma alternativa para o ambiente

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    José Machado

    2016-05-01

    Full Text Available The strawberry culture demand for labor, it requires special care to prevent pest problems. Its cultivation is characterized by indiscriminate use of pesticides, which leads researchers to seek more natural alternatives for improving soil conditions, and decreased use of chemicals. In this context, lichens can be a viable alternative, since its properties in modifying the chemical composition of the soil, addition of antimicrobial action and their insecticidal substances. The aim of work is to inform about the strawberry cultivation your climate conditions and possible use of lichens in your cultivation.

  11. High acidity tolerance in lichens with fumarprotocetraric, perlatolic or thamnolic acids is correlated with low pKa1 values of these lichen substances.

    Science.gov (United States)

    Hauck, Markus; Jürgens, Sascha-René; Huneck, Siegfried; Leuschner, Christoph

    2009-10-01

    The depsidone fumarprotocetraric acid as well as the depsides perlatolic and thamnolic acids are lichen secondary metabolites. Their first dissociation constants (pK(a1)) in methanol were determined to be 2.7 for perlatolic acid and 2.8 for fumarprotocetraric and thamnolic acids by UV spectroscopy. Lower pK(a1) values are, so far, not known from lichen substances. Several lichens producing at least one of these compounds are known for their outstanding tolerance to acidic air pollution. This is demonstrated by evaluating published pH preferences for central European lichens. The low pK(a1) values suggest that strong dissociation of the studied lichen substances is a prerequisite for the occurrence of lichens with these compounds on very acidic substrata, as protonated lichen substances of different chemical groups, but not their conjugated bases, are known to shuttle protons into the cytoplasm and thereby apparently damage lichens.

  12. Chemical changes of minerals trapped in the lichen Trapelia involuta. Implication for lichen effect on mobility of uranium and toxic metals

    International Nuclear Information System (INIS)

    Kasama, Takeshi; Murakami, Takashi; Ohnuki, Toshihiko

    2002-01-01

    To elucidate development of minerals trapped in a lichen, we examined the lichen Trapelia involuta growing directly on secondary uranyl minerals and U-enriched Fe oxide and hydroxide minerals. Sericite and other minerals in the underlying rock are trapped in the lichen T. involuta during its biological growth and chemically changed by lichen activities. The presence of chemically changed sericite accompanied by an Fe-bearing mineral in the lichen suggests that dissolution of sericite is promoted mainly by polysaccharides excreted by the lichen. Oxalic acid or lichen acids absent in the medulla may not play an important role in the dissolution. Our results suggest that lichens on metal-rich surface affect the mobility of uranium and other toxic metals through dissolution followed by trap of minerals from the underlying rock. (author)

  13. Lichen ecology of the Scunthorpe heathlands. I. Mineral accumulation

    Energy Technology Data Exchange (ETDEWEB)

    Seaward, M R.D.

    1973-01-01

    An investigation into the distributional and ecological characteristics of the terricolous lichen flora of the Scunthorpe heathlands is described. The Risby Warren area was especially studied, because there is a noticeable terricolous lichen desert and distinctive zonation of lichen communities, each of which incorporates Peltigera rufescens. Peltigera rufescens appeared to be quite tolerant of air pollution in this region, and occurred in sufficient quantities for periodic sampling; this proved valuable for determination of the sulfur, chromium, copper, iron, lead, manganese, and nickel content of the thalli along a 780 m transect. Frequency assessments, together with these element determinations, revealed sharp qualitative and quantitative improvements in the lichen flora with increasing distance from the pollution sources. The stable lichen pattern, together with the mineral accumulation measurements, was indicative of a pollution dome effect operating to a distance of approximately 3 km. Within 100 to 200 m of this critical distance, lichen material had a pronounced metallic accumulation; the latter was compared with urban and herbarium material. The possible use of lichens for the sampling of ambient environmental conditions is discussed.

  14. INFLUENCE OF MINING AND METAL INDUSTRY ON PHYSCIA LICHENS

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    Kachinskaya V.V.

    2015-04-01

    Full Text Available The comparative analysis of lichens Physcia. Рopulation at different levels of aerotechnogenic pollution of industrial mining – metallurgical complex of Krivyi Rig Basin. In the highway area there was found the worsening living conditions of thallus at the lichens Physcia, manifested in the reduction of a projective cover and reducing of the size of thallus with the increasing of the degree of their damage. It is set that specific composition and conformities to law of distribution of cladinas is determined the type of the industrial loading. Predominance at the lichens of crustaceous cladinas, insignificant participation of fissile cladinas and complete absence of bushy forms is the possible consequence of industrial influence. We registered some 3 species of epiphytic lichens, namely Phaeophyscia nigricans, Physcia tenella, Physcia adscendens in a residential zone, while on conditional control area we found Physcia orbicularis. The dominant species was scum-like shape Phaeophyscia nigricans, Physcia adscendens, Physcia tenella, while on conditional control region we marked predominance of Physcia orbicularis and did not registered bushy lichens form. We also divided the lichens into two groups according to the resistance towards air pollution - moderate (2 species, Phaeophyscia nigricans, Physcia tenella and toxic-resistant (2 species, Physcia orbicularis, Physcia adscendens. Epiphytic lichens in terms of residential areas compared to conventionally control area characterized by a decrease of morphometric parameters of the melt. Key results can be used to predict the state of ecosystems using lichenoindication in terms of industrial regions of Ukraine.

  15. Lichen ranges, animal densities and production in Finnish reindeer management

    Directory of Open Access Journals (Sweden)

    T. Helle

    1990-09-01

    Full Text Available In the 1970s, mean lichen biomass ranged by the earmark districts (comprising of 2-9 adjacent herding associations between 54 kg and 380 kg DM per ha correlating negatively with animal density per lichen ranges (range 1.5 - 14.3 ind. per km2. Biomasses were far below economic carrying capacity of lichen ranges (900 kg DM per ha. The condition of lichen ranges was poorest in the southern half of the area where alternative food to reindeer lichens (Deschampsia flexuosa, arboreal lichens and supplementary feeding was available. In 1980-86, recruitment (calves per 100 females was 33% higher than in the 1970's, on an average (65 vs. 49, despite a 90% increase in animal numbers between 1970 and 1986; recruitment has not been dependent on the condition of lichen ranges. The increase in production has been some higher than expected on the basis of animal numbers. The reasons for the increasing trends in animal numbers, recruitment and production remains some unclear, but they may include favorable winter conditions, supplementary feeding, medical treatment against parasites and proper harvesting policy.

  16. The immunostimulating role of lichen polysaccharides: a review.

    Science.gov (United States)

    Shrestha, Gajendra; St Clair, Larry L; O'Neill, Kim L

    2015-03-01

    The immune system has capacity to suppress the development or progression of various malignancies including cancer. Research on the immunomodulating properties of polysaccharides obtained from plants, microorganisms, marine organisms, and fungi is growing rapidly. Among the various potential sources, lichens, symbiotic systems involving a fungus and an alga and/or a cyanobacterium, show promise as a potential source of immunomodulating compounds. It is well known that lichens produce an abundance of structurally diverse polysaccharides. However, only a limited number of studies have explored the immunostimulating properties of lichen polysaccharides. Published studies have shown that some lichen polysaccharides enhance production of nitrous oxide (NO) by macrophages and also alter the production levels of various proinflammatory and antiinflammatory cytokines (IL-10, IL-12, IL-1β, TNF-α, and IFN-α/β) by macrophages and dendritic cells. Although there are only a limited number of studies examining the role of lichen polysaccharides, all results suggest that lichen polysaccharides can induce immunomodulatory responses in macrophages and dendritic cells. Thus, a detailed evaluation of immunomodulatory capacity of lichen polysaccharides could provide a unique opportunity for the discovery of novel therapeutic agents. Copyright © 2014 John Wiley & Sons, Ltd.

  17. Usnic acid controls the acidity tolerance of lichens

    International Nuclear Information System (INIS)

    Hauck, Markus; Juergens, Sascha-Rene

    2008-01-01

    The hypotheses were tested that, firstly, lichens producing the dibenzofuran usnic acid colonize substrates characterized by specific pH ranges, secondly, this preferred pH is in a range where soluble usnic acid and its corresponding anion occur in similar concentrations, and thirdly, usnic acid makes lichens vulnerable to acidity. Lichens with usnic acid prefer an ambient pH range between 3.5 and 5.5 with an optimum between 4.0 and 4.5. This optimum is close to the pK a1 value of usnic acid of 4.4. Below this optimum pH, dissolved SO 2 reduces the chlorophyll fluorescence yield more in lichens with than without their natural content of usnic acid. This suggests that usnic acid influences the acidity tolerance of lichens. The putative mechanism of the limited acidity tolerance of usnic acid-containing lichens is the acidification of the cytosol by molecules of protonated usnic acid shuttling protons through the plasma membrane at an apoplastic pH a1 . - Combined field and experimental data suggest that usnic acid makes lichens sensitive to acidity at pH <3.5

  18. Non destructive SXRF analysis of heavy elements in lichens

    International Nuclear Information System (INIS)

    Ramos, M.T.; Figueiredo, M.O.; Pereira da Silva, T.; Basto, M.J.; Chevallier, P.

    2000-01-01

    Various species incrusting granitic and calcareous rocks were collected at different places covering a large span of atmospheric conditions. They were chemically studied by synchrotron- induced X-ray fluorescence (SXRF), a nondestructive technique of outmost importance in the field, allowing for a future use of the same lichen fragments in further tests. This study proved that lichens - at least the saxicolous species - concentrate heavy elements recognized as strong pollutants, like lead and bromine, irrespective the environmental availability of these elements, either in the atmosphere or in the rock substrate, partially frustrating the use of saxicolous lichens as pollution monitors. (author)

  19. A potential peptide pathway from viruses to oral lichen planus.

    Science.gov (United States)

    Lucchese, Alberta

    2015-06-01

    Oral lichen planus is an idiopathic inflammatory disease of oral mucous membranes, characterized by an autoimmune epidermis attack by T cells. It remains unknown, however, how such aggressive T cells are activated in vivo to cause epidermal damage. This study analyzes the relationship at the peptide level between viruses and oral lichen planus disease. Four potentially immunogenic peptides (SSSSSSS, QEQLEKA, LLLLLLA, and MLSGNAG) are found to be shared between HCV, EBV, HHV-7, HSV-1, and CMV and three human proteins (namely pinin, desmoglein-3, and plectin). The described peptide sharing might be of help in deciphering the still unexplained immunopathogenic pathway that leads to oral lichen planus. © 2015 Wiley Periodicals, Inc.

  20. Photodynamic therapy in treatment of severe oral lichen planus.

    Science.gov (United States)

    Rabinovich, O F; Rabinovich, I M; Guseva, A V

    2016-01-01

    The aim of the study was to elaborate the rationale for the application of photodynamic therapy in complex treatment of patient with severe oral lichen planus. Complex clinical and laboratory examination and treatment was performed in 54 patients divided on 3 groups. Diagnosis of oral lichen planus was based on clinical, histological and immunohistochemical features. Group 1 received standard treatment, in the second group photodynamic therapy was conducted in addition to conventional treatment, patients in the third group received only photodynamic therapy. The study results proved photodynamic therapy to be useful tool in complex treatment of severe oral lichen planus.

  1. Antigenotoxicity of Depsidones Isolated from Brazilian Lichens

    Directory of Open Access Journals (Sweden)

    Zaira da Rosa Guterres

    2017-04-01

    Full Text Available Although phenolic compounds produced by lichens have been widely investigated in antitumor assays, only a small number have been evaluated for mutagenicity and genotoxicity. This study evaluated protocetraric, hypostictic, psoromic, and salazinic acids for their potential genotoxic or antigenotoxic activity against somatic cells of Drosophila melanogaster. These compounds were isolated from the lichens Parmotrema dilatatum, Pseudoparmelia sphaerosphora, Usnea jamaicensis, and Parmotrema cetratum, respectively, collected from the Brazilian Cerrado biome. The compounds were evaluated at 0.75, 1.5, 3.0, and 6.0 mmol L–1 using the SMART test, employing standard and high-bioactivation crosses of Drosophila melanogaster. Doxorubicin (DXR was the positive control. Psoromic and salazinic acids proved toxic at 6.0 mM. None of the compounds evaluated exhibited mutagenicity, but each of them significantly reduced genetic damage caused by DXR, proving antigenotoxic when tested on somatic cells of D. melanogaster. DOI: http://dx.doi.org/10.17807/orbital.v9i1.897

  2. Volatile constituents of selected Parmeliaceae lichens

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    GORDANA S. STOJANOVIĆ

    2011-07-01

    Full Text Available The acetone soluble fraction of the methanol extracts of Parmeliaceae lichens: Hypogymnia physodes, Evernia prunastri and Parmelia sulcata, growing on the same host tree (Prunus domestica and at the same locality was analyzed for the first time by GC and GC–MS. The major identified components were olivetol (33.5 % of the H. physodes extract, atraric acid (30.1 and 30.3 % of the E. prunastri and P. sulcata extracts, respectively, orcinol (25.0 % of the E. prunastri extract, vitamin E (24.7 % of the P. sulcata extract and olivetonide (15.7 % of the H. physodes extract. Even though all the identified compounds are known, a number of them were found for the first time in the examined lichens, i.e., orcinol monomethyl ether (H. physodes, orcinol, atranol, lichesterol, ergosterol (H. physodes and P. sulcata, methyl haematommate, atraric acid, olivetol, vitamin E (H. physodes and P. sulcata and b-sitosterol (P. sulcata.

  3. Pigmented Oral Lichen Planus: A Case Report

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    Firstine Kelsi Hartanto

    2017-09-01

    Full Text Available Background: Lichen planus is a chronic muccocutaneous inflammatory disorder. Oral lichen planus (OLP has certain specific characteristics in its clinical presentation, but can also be presented in forms resembling other diseases. This may introduce difficulty in the diagnostic process. It has been reported that OLP affects between 0.1 to 4% individuals, predominantly women and people over 40 years old. Case Report: A 46-year-old woman complained of a non-healing ulcer present for 1.5 months. Intraorally, multiple white striae with prominent central areas of brownish hyperpigmentation were apparent on the right and left buccal mucosa, right and left buccal sulcus, and lateral and dorsum of the tongue. A biopsy was completed and the histopathology features confirmed the diagnosis of OLP. For the initial treatment, a topical corticosteroid was prescribed, followed by steroid mouthwash. Response to this treatment was positive. OLP has been frequently reported to affect women over the age of 40, with psychological stress as a primary predisposing factor. The clinical presentation is characteristic of Wickham’s striae with erosive areas. However, a biopsy and histopathological examination is mandatory to confirm the diagnosis. The clinical feature of pigmented OLP has been reported and confirmed by microscopic finding of band-like lymphocytic appearance which is the pathognomonic features of OLP, along with basal cell liquefaction degeneration, and melanin in continence at the lamina propria. Conclusion: Pigmented OLP is a variant of erosive OLP. Anamnesis, clinical presentation, and histopathological examination confirm diagnosis.

  4. Lichen planus secondary to hepatitis B vaccination

    Directory of Open Access Journals (Sweden)

    Agrawal Akhilesh

    2004-07-01

    Full Text Available The association of lichen planus (LP with liver diseases is now well established. Recent reports suggest that the hepatitis viruses may play a central role in this association. Lichen planus following hepatitis B vaccination is much more unusual. A 19-year-old previously healthy male developed itchy violaceous papules and plaques over the upper extremities eight to ten days after the first injection of hepatitis B vaccine. He developed similar lesions over the upper trunk, neck and lower leg after the second and third injections. A skin biopsy showed a lichenoid tissue reaction. Direct immunofluorescence (DIF showed multiple colloid bodies and a strong continuous ragged basement membrane zone (BMZ band with fibrinogen. HbsAg by ELISA and anti-HCV antibodies were negative. The patient was treated with oral steroids and the lesions improved. LP is a pruritic inflammatory dermatosis of unknown origin. An increased prevalence of liver disease in patient with LP has been reported. Since the first case reported by Rebora in 1990, about 15 cases of LP occurring after hepatitis B vaccination have been reported in the literature irrespective of the type of vaccine used.

  5. [Dynamic concept of oral lichen planus. The diagnosis easy at early stages may become difficult in ancient lichen planus].

    Science.gov (United States)

    Lombardi, Tommaso; Küffer, Roger

    2016-02-01

    Dynamic concept of oral lichen planus. The diagnosis easy at early stages may become difficult in ancient lichen planus. Lichen planus is a chronic inflammatory dermatosis of the skin, skin appendages and mucous membranes, which frequently affects the oral mucosa. Its aetiology still remains unknown, and currently accepted pathogenesis is that of an autoimmune cell-mediated disease. To the contrary of skin lichen planus, oral lichen planus is a long-term chronic disease with dynamic evolution, in which progressive and profound changes of the clinical and histopathological aspects occur over time and under the influence of various exogenous factors. By convention, in the history of the oral lichen planus four successive stages can be distinguished without well-defined boundaries between them. These stages can be defined as an initial phase; a long intermediate phase with alternating periods of activity and quiescence, which has a gradually increasing risk of malignant transformation; a late stage which activity is traditionally diminished; and a post-lichen cicatricial stage with an absent or negligible and undetectable activity, often undiagnosed because clinically unrecognized; in this stage, the lesion does not respond to usual treatments, but retains the same risk of malignant transformation. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  6. Gymnoxanthella radiolariae gen. et sp. nov. (Dinophyceae), a dinoflagellate symbiont from solitary polycystine radiolarians.

    Science.gov (United States)

    Yuasa, Tomoko; Horiguchi, Takeo; Mayama, Shigeki; Takahashi, Osamu

    2016-02-01

    The symbiotic dinoflagellate Gymnoxanthella radiolariae T. Yuasa et T. Horiguchi gen. et sp. nov. isolated from polycystine radiolarians is described herein based on light, scanning and transmission electron microscopy as well as molecular phylogenetic analyses of SSU and LSU rDNA sequences. Motile cells of G. radiolariae were obtained in culture, and appeared to be unarmored. The cells were 9.1-11.4 μm long and 5.7-9.4 μm wide, and oval to elongate oval in the ventral view. They possessed an counterclockwise horseshoe-shaped apical groove, a nuclear envelope with vesicular chambers, cingulum displacement with one cingulum width, and the nuclear fibrous connective; all of these are characteristics of Gymnodinium sensu stricto (Gymnodinium s.s.). Molecular phylogenetic analyses also indicated that G. radiolariae belongs to the clade of Gymnodinium s.s. However, in our molecular phylogenetic trees, G. radiolariae was distantly related to Gymnodinium fuscum, the type species of Gymnodinium. Based on the consistent morphological, genetic, and ecological divergence of our species with the other genera and species of Gymnodinium s.s., we considered it justified to erect a new, separate genus and species G. radiolariae gen. et sp. nov. As for the peridinioid symbiont of radiolarians, Brandtodinium has been erected as a new genus instead of Zooxanthella, but the name Zooxanthella is still valid. Brandtodinium is a junior synonym of Zooxanthella. Our results suggest that at least two dinoflagellate symbiont species, peridinioid Zooxanthella nutricula and gymnodinioid G. radiolariae, exist in radiolarians, and that they may have been mixed and reported as "Z. nutricula" since the 19th century. © 2016 Phycological Society of America.

  7. Lichens of the alps as biomonitors for radioactive fallout

    International Nuclear Information System (INIS)

    Hofmann, W.; Gastberger, M.; Tuerk, R.

    1995-07-01

    A number of surveys has shown, that shortly after a radioactive fallout lichens are highly contaminated and their contamination correlates well with the soil deposition data. One of the major advantages of lichens is that samples can be collected from quite large areas, thereby getting an average contamination of this area. Especially in mountain ecosystems, lichens could gain great importance as biomonitors, because many lichens grow in this area. Moreover, the collection of soil samples can be very difficult. For this survey soil and lichen samples were collected from a mountain called Stubnerkogel, which is located in the south of the province of Salzburg. The samples were taken in the summer of 1993, that means more than 7 years after the nuclear accident in Chernobyl. The aim of this study was to find out, if some years after a nuclear fallout has occurred lichens are still suitable biological detectors of the radioactive contamination. The lichen samples had 137 Cs activities between 400 and 5.000 Bq per kg dry weight. Even for small samples these comparatively high activities are easy to measure, because of their long life expectancy lichens can be used as biomonitors for a radioactive contamination which happened a few years ago. One sampling site allowed the collection of different lichen species in a very restricted area. It was possible to find specific differences in the 137 Cs contamination between the various species; Cetraria islandica, Cladonia arbuscula and Cladonia rangiferina had the highest contamination levels. These three species are very common in alpine regions, so they prove to be especially suitable biomonitors of radioactive fallout. Furthermore it was partly possible to find small amounts of 137 Cs in the soil, which originate from nuclear weapons tests (this was impossible for any of the lichen samples). Thus lichens can be very useful when a fallout which occurred shortly ago should be separated from a fallout which had occurred a long

  8. Classical lichen planus and lichen planus pigmentosus inversus overlap with dermoscopic features

    Directory of Open Access Journals (Sweden)

    Şule Güngör

    2014-01-01

    Full Text Available A 35-year-old man was referred to our hospital with a 3 months history of itchy cutaneous eruption on the trunk and asymptomatic cutaneous eruption on both groins. Physical examination revealed several, purplish-brown, scaly papules on the trunk and well-circumscribed, brown patchs in a linear distribution, on the bilateral inguinal regions. Dermoscopic examination of papules on the trunk revealed white crossing lines surrounded by brown dots; dermoscopic examination of patchs on groins revealed gray-brown dots and globules. According to histological, dermoscopical and clinical changes, the diagnoses of classical lichen planus (LP for the lesions on the trunk; and lichen planus pigmentosus inversus (LPPI for the lesions on the inguinal regions were made. Inhere we have described a rare case of LPPI and classical LP with dermoscopic features; and we suggest that LPPI is a variant of classical LP.

  9. The lichens, tritium and carbon 14 integrators; Les lichens, integrateurs de tritium et de carbone 14

    Energy Technology Data Exchange (ETDEWEB)

    Daillant, O

    2007-07-01

    The present report concerns a research for the tritium and for the carbon 14 in lichens in a spirit of bio-indication: the first results appear in Daillant and al (2004 ) and additional results were presented to the congress B.I.O.M.A.P. in Slovenia, organized collectively by the institute Josef Stefan from Ljubljana and the international atomic energy agency from Vienna (Daillant and al 2003). (N.C.)

  10. Culture.

    Science.gov (United States)

    Smith, Timothy B; Rodríguez, Melanie Domenech; Bernal, Guillermo

    2011-02-01

    This article summarizes the definitions, means, and research of adapting psychotherapy to clients' cultural backgrounds. We begin by reviewing the prevailing definitions of cultural adaptation and providing a clinical example. We present an original meta-analysis of 65 experimental and quasi-experimental studies involving 8,620 participants. The omnibus effect size of d = .46 indicates that treatments specifically adapted for clients of color were moderately more effective with that clientele than traditional treatments. The most effective treatments tended to be those with greater numbers of cultural adaptations. Mental health services targeted to a specific cultural group were several times more effective than those provided to clients from a variety of cultural backgrounds. We recommend a series of research-supported therapeutic practices that account for clients' culture, with culture-specific treatments being more effective than generally culture-sensitive treatments. © 2010 Wiley Periodicals, Inc.

  11. First supplement to the lichen checklist of South Africa

    Directory of Open Access Journals (Sweden)

    Teuvo Ahti

    2016-07-01

    Full Text Available Details are given of errors and additions to the recently published checklist of lichens reported from South Africa (Fryday 2015. The overall number of taxa reported from South Africa is increased by one, to 1751.

  12. Lichen secondary metabolites as DNA-interacting agents

    Czech Academy of Sciences Publication Activity Database

    Plšíková, J.; Štěpánková, Jana; Kašpárková, Jana; Brabec, Viktor; Bačkor, M.; Kozurková, M.

    2014-01-01

    Roč. 28, č. 2 (2014), s. 182-186 ISSN 0887-2333 Institutional support: RVO:68081707 Keywords : Lichens * DNA-binding * Topoisomerase I, II Subject RIV: BO - Biophysics Impact factor: 2.903, year: 2014

  13. Experimental strain analysis of Clarens Sandstone colonised by endolithic lichens

    Directory of Open Access Journals (Sweden)

    D. Wessels

    1995-08-01

    Full Text Available Endolithic lichens occur commonly on Clarens Sandstone in South Africa, where they significantly contribute to the weathering of sandstone by means of mechanical and chemical weathering processes. This preliminary investigation reports on the success- ful use of strain gauges in detecting strain differences between sandstone without epilithic lichens and sandstone colonised by the euendolithic lichen Lecidea aff. sarcogynoides Korb. Mechanical weathering, expressed as strain changes, in Clarens Sandstone was studied during the transition from relatively dry winter to wet summer conditions. Daily weathering of sandstone due to thermal expansion and contraction of colonised and uncolonised sandstone could be shown. Our results show that liquid water in sandstone enhances the mechanical weathering of uncolonised Clarens Sandstone while water in the gaseous phase enhances mechanical weathering of sandstone by euendolithic lichens.

  14. Antarctic Epilithic Lichens as Niches for Black Meristematic Fungi

    Directory of Open Access Journals (Sweden)

    Laura Zucconi

    2013-05-01

    Full Text Available Sixteen epilithic lichen samples (13 species, collected from seven locations in Northern and Southern Victoria Land in Antarctica, were investigated for the presence of black fungi. Thirteen fungal strains isolated were studied by both morphological and molecular methods. Nuclear ribosomal 18S gene sequences were used together with the most similar published and unpublished sequences of fungi from other sources, to reconstruct an ML tree. Most of the studied fungi could be grouped together with described or still unnamed rock-inhabiting species in lichen dominated Antarctic cryptoendolithic communities. At the edge of life, epilithic lichens withdraw inside the airspaces of rocks to find conditions still compatible with life; this study provides evidence, for the first time, that the same microbes associated to epilithic thalli also have the same fate and chose endolithic life. These results support the concept of lichens being complex symbiotic systems, which offer attractive and sheltered habitats for other microbes.

  15. Photosynthesis in a sub-Antarctic shore-zone lichen

    NARCIS (Netherlands)

    Smith, V.; Gremmen, N.J.M.

    2001-01-01

    Photosynthetic responses to moisture, light, temperature, salinity and inorganic nitrogen fertilization are reported for a shore-zone lichen Turgidiusculum complicatulum (formerly Mastodia tesselata), a possible recent introduction to sub-Antarctic Marion Island. Optimum moisture contents for net

  16. Lichens as indicators of tritium and radiocarbon contamination

    International Nuclear Information System (INIS)

    Daillant, Olivier; Kirchner, Gerald; Pigree, Gilbert; Porstendorfer, Justin

    2004-01-01

    Lichens were collected in France in the surroundings of a military nuclear facility in Burgundy, near the la Hague reprocessing plant and in an area away from any direct source of contamination. Organically bound tritium (OBT) has been analysed on 18 samples and radiocarbon on 11. It appeared that on the most contaminated spots, the OBT activity in lichens was higher than the background by a factor of 1000 and was still a factor 10-100 at a distance of 20 km from the source. Radiocarbon from la Hague could be traced by lichens. The slow metabolism of lichens makes them suitable for the follow-up of 3 H and 14 C, which have been incorporated by photosynthesis

  17. Nitrogen fixation in lichens is important for improved rock weathering

    Indian Academy of Sciences (India)

    MADU

    1996), suggesting that fungal acid production is altered in the lichen. Weathering .... 5019 biofilm, (vii) S. recemosum + B. elkanii SEMIA 5019 biofilm, and (viii) the .... chemical factors in soil mineral wethering; in Interactions of soil minerals with ...

  18. Lichens as biomonitors of uranium in the Balkan area

    Energy Technology Data Exchange (ETDEWEB)

    Loppi, S.; Riccobono, F.; Zhang, Z.H.; Savic, S.; Ivanov, D.; Pirintsos, S.A

    2003-09-01

    Widespread contamination by depleted uranium was not detected in the Balkan area. - The contribution of the conflict of 1999 to the environmental levels of uranium in the Balkan area was evaluated by means of lichens used as biomonitors. The average U concentration found in lichens in the present study was in line with the values reported for lichens from other countries and well below the levels found in lichens collected in areas with natural or anthropogenic sources of U. Measurement of isotopic ratios {sup 235}U/{sup 238}U allowed to exclude the presence of depleted uranium. According to these results, we could not detect widespread environmental contamination by depleted uranium in the Balkan area.

  19. Prevalence of oral lichen planus in Gizan, Saudi Arabia

    International Nuclear Information System (INIS)

    Salem, Gamil

    1990-01-01

    This paper reports on the prevalence of oral lichen planus among 4277 dental patients aged 18-73 years, seen in the Dental Department, King Fahad Central Hospital, Gizan, Saudi Arabia, between 1982 and 1987. Oral mucosal lesions, diagnosed as lichen planus, were clinically and histologically identified in 72 subjects (40 males and 32 females). The average age of the affected group was 49 years. No correlation was evident between lichen planus and tobacco habits in this study, nor was there any association with diabetes or hypertension. The average period of follow-up was 3.2 years, during which time 4 patients developed malignant transformation of their oral lesions. The prevalence of lichen planus in this study was 1.7%, which is higher than the prevalence figures reported earlier for this disease in Saudi Arabia. (author)

  20. Metatranscriptomics reveal differences in in situ energy and nitrogen metabolism among hydrothermal vent snail symbionts.

    Science.gov (United States)

    Sanders, J G; Beinart, R A; Stewart, F J; Delong, E F; Girguis, P R

    2013-08-01

    Despite the ubiquity of chemoautotrophic symbioses at hydrothermal vents, our understanding of the influence of environmental chemistry on symbiont metabolism is limited. Transcriptomic analyses are useful for linking physiological poise to environmental conditions, but recovering samples from the deep sea is challenging, as the long recovery times can change expression profiles before preservation. Here, we present a novel, in situ RNA sampling and preservation device, which we used to compare the symbiont metatranscriptomes associated with Alviniconcha, a genus of vent snail, in which specific host-symbiont combinations are predictably distributed across a regional geochemical gradient. Metatranscriptomes of these symbionts reveal key differences in energy and nitrogen metabolism relating to both environmental chemistry (that is, the relative expression of genes) and symbiont phylogeny (that is, the specific pathways employed). Unexpectedly, dramatic differences in expression of transposases and flagellar genes suggest that different symbiont types may also have distinct life histories. These data further our understanding of these symbionts' metabolic capabilities and their expression in situ, and suggest an important role for symbionts in mediating their hosts' interaction with regional-scale differences in geochemistry.

  1. Ephemeral windows of opportunity for horizontal transmission of fungal symbionts in leaf-cutting ants

    DEFF Research Database (Denmark)

    Poulsen, Michael; Fernández-Marín, Hermógenes; Currie, Cameron R.

    2009-01-01

    Evolutionary theory predicts that hosts are selected to prevent mixing of genetically different symbionts when competition among lineages reduces the productivity of a mutualism. The symbionts themselves may also defend their interests: recent studies of Acromyrmex leaf-cutting ants showed that s...

  2. Diversity and Phylogenetic Analyses of Bacterial Symbionts in Three Whitefly Species from Southeast Europe

    Science.gov (United States)

    Skaljac, Marisa; Zanic, Katja; Puizina, Jasna; Lepen Pleic, Ivana; Ghanim, Murad

    2017-01-01

    Bemisia tabaci (Gennadius), Trialeurodes vaporariorum (Westwood), and Siphoninus phillyreae (Haliday) are whitefly species that harm agricultural crops in many regions of the world. These insects live in close association with bacterial symbionts that affect host fitness and adaptation to the environment. In the current study, we surveyed the infection of whitefly populations in Southeast Europe by various bacterial symbionts and performed phylogenetic analyses on the different symbionts detected. Arsenophonus and Hamiltonella were the most prevalent symbionts in all three whitefly species. Rickettsia was found to infect mainly B. tabaci, while Wolbachia mainly infected both B. tabaci and S. phillyreae. Furthermore, Cardinium was rarely found in the investigated whitefly populations, while Fritschea was never found in any of the whitefly species tested. Phylogenetic analyses revealed a diversity of several symbionts (e.g., Hamiltonella, Arsenophonus, Rickettsia), which appeared in several clades. Reproductively isolated B. tabaci and T. vaporariorum shared the same (or highly similar) Hamiltonella and Arsenophonus, while these symbionts were distinctive in S. phillyreae. Interestingly, Arsenophonus from S. phillyreae did not cluster with any of the reported sequences, which could indicate the presence of Arsenophonus, not previously associated with whiteflies. In this study, symbionts (Wolbachia, Rickettsia, and Cardinium) known to infect a wide range of insects each clustered in the same clades independently of the whitefly species. These results indicate horizontal transmission of bacterial symbionts between reproductively isolated whitefly species, a mechanism that can establish new infections that did not previously exist in whiteflies. PMID:29053633

  3. Presumptive horizontal symbiont transmission in the fungus-growing termite Macrotermes natalensis

    NARCIS (Netherlands)

    Fine Licht, de H.H.; Boomsma, J.J.; Aanen, D.K.

    2006-01-01

    All colonies of the fungus-growing termite Macrotermes natalensis studied so far are associated with a single genetically variable lineage of Termitomyces symbionts. Such limited genetic variation of symbionts and the absence of sexual fruiting bodies (mushrooms) on M. natalensis mounds would be

  4. Diversity and Phylogenetic Analyses of Bacterial Symbionts in Three Whitefly Species from Southeast Europe

    Directory of Open Access Journals (Sweden)

    Marisa Skaljac

    2017-10-01

    Full Text Available Bemisia tabaci (Gennadius, Trialeurodes vaporariorum (Westwood, and Siphoninus phillyreae (Haliday are whitefly species that harm agricultural crops in many regions of the world. These insects live in close association with bacterial symbionts that affect host fitness and adaptation to the environment. In the current study, we surveyed the infection of whitefly populations in Southeast Europe by various bacterial symbionts and performed phylogenetic analyses on the different symbionts detected. Arsenophonus and Hamiltonella were the most prevalent symbionts in all three whitefly species. Rickettsia was found to infect mainly B. tabaci, while Wolbachia mainly infected both B. tabaci and S. phillyreae. Furthermore, Cardinium was rarely found in the investigated whitefly populations, while Fritschea was never found in any of the whitefly species tested. Phylogenetic analyses revealed a diversity of several symbionts (e.g., Hamiltonella, Arsenophonus, Rickettsia, which appeared in several clades. Reproductively isolated B. tabaci and T. vaporariorum shared the same (or highly similar Hamiltonella and Arsenophonus, while these symbionts were distinctive in S. phillyreae. Interestingly, Arsenophonus from S. phillyreae did not cluster with any of the reported sequences, which could indicate the presence of Arsenophonus, not previously associated with whiteflies. In this study, symbionts (Wolbachia, Rickettsia, and Cardinium known to infect a wide range of insects each clustered in the same clades independently of the whitefly species. These results indicate horizontal transmission of bacterial symbionts between reproductively isolated whitefly species, a mechanism that can establish new infections that did not previously exist in whiteflies.

  5. The role of symbiont genetic distance and potential adaptability in host preference towards Pseudonocardia symbionts in Acromyrmex leaf-cutting ants

    DEFF Research Database (Denmark)

    Thomas-Poulsen, Michael; Maynard, Janielle; Roland, Damien L.

    2011-01-01

    Fungus-growing ants display symbiont preference in behavioral assays, both towards the fungus they cultivate for food and Actinobacteria they maintain on their cuticle for antibiotic production against parasites. These Actinobacteria, genus Pseudonocardia Henssen (Pseudonocardiacea: Actinomycetales...

  6. Lichenized fungi of a chestnut grove in Livari (Rumija, Montenegro)

    Science.gov (United States)

    Mayrhofer, Helmut; Drescher, Anton; Stešević, Danijela; Bilovitz, Peter O.

    2016-01-01

    Sixty taxa (59 species and 1 variety) of lichenized fungi are reported from a chestnut grove in Livari. The majority of them (55 species and 1 variety) occurred on Castanea sativa. The recently described Xylographa soralifera is new to the Balkan Peninsula. The lichenicolous fungus Monodictys epilepraria growing on Lepraria rigidula is new to Montenegro. The lichen mycota is compared with similar localities in Italy and Switzerland. The species composition in Livari is most similar to the Montieri site in Tuscany. PMID:26869743

  7. Description of spatial and temporal distributions of epiphytic lichens

    OpenAIRE

    Lättman, Håkan

    2008-01-01

    Lichens are, in most cases, sensitive to anthropogenic factors such as air pollution, global warming, forestry and fragmentation. Two studies are included in this thesis. The first is an evaluation of the importance of old oak for the rare epiphytic lichen Cliostomum corrugatum (Ach.) Fr. This study analysed whether C. corrugatum was limited by dispersal or restricted to tree stands with an unbroken continuity or the substrate old oaks. The results provide evidence that the investigated five ...

  8. Community assembly in epiphytic lichens in early stages of colonization.

    Science.gov (United States)

    Gjerde, Ivar; Blom, Hans H; Lindblom, Louise; Saetersdal, Magne; Schei, Fride Høstad

    2012-04-01

    Colonization studies may function as natural experiments and have the potential of addressing important questions about community assembly. We studied colonization for a guild of epiphytic lichens in a former treeless heathland area of 170 km2 in southwest Norway. We investigated if epiphytic lichen species richness and composition on aspen (Populus tremula) trees corresponded to a random draw of lichen individuals from the regional species pool. We compared lichen communities of isolated young (55-120 yr) and old (140-200 yr) forest patches in the heathland area to those of aspen forest in an adjacent reference area that has been forested for a long time. All thalli (lichen bodies) of 32 selected lichen species on trunks of aspen were recorded in 35 aspen sites. When data for each site category (young, old, and reference) were pooled, we found the species richness by rarefaction to be similar for reference sites and old sites, but significantly lower for young sites. The depauperated species richness of young sites was accompanied by a skew in species composition and absence of several species that were common in the reference sites. In contrast, genetic variation screened with neutral microsatellite markers in the lichen species Lobaria pulmonaria showed no significant differences between site categories. Our null hypothesis of a neutral species assembly in young sites corresponding to a random draw from the regional species pool was rejected, whereas an alternative hypothesis based on differences in colonization capacity among species was supported. The results indicate that for the habitat configuration in the heathland area (isolated patches constituting lichen communities may need a colonization time of 100-150 yr for species richness to level off, but given enough time, isolation will not affect species richness. We suggest that this contradiction to expectations from classical island equilibrium theory results from low extinction rates.

  9. Lichen Persistence and Recovery in Response to Varied Volcanic Disturbances

    Science.gov (United States)

    Nelson, P.; Wheeler, T. B.

    2015-12-01

    Volcanic eruptions produce many ecological disturbances that structure vegetation. While lichens are sensitive to disturbances, little is known about their responses to volcanic disturbances, except for colonization of lava. We examined lichen community responses through time to different disturbances produced by the May 1, 2008 eruption of Volcan Chaiten in south-central Chile. Pre-eruption vegetation near the volcano was old-growth Valdivian temperate rainforest dominated by closed-canopy Nothofagus sp... In 2012, we installed thirteen 1-acre plots across volcanic disturbance zones on which a time-constrained search was done for all macrolichen species, each of which was assigned an approximate log10 categorical abundance. We also installed a 0.2 m2 quadrat on two representative trees per plot for repeat photography of lichen cover. We remeasured at least one plot per disturbance zone in 2014 and re-photographed tree quadrats in 2013 and 2014. We then analyzed species composition and abundance differences among disturbance zones. In 2012, the blast (pyroclastic density flow), scorch (standing scorched forest at the edge of the blast) and deep tephra (>10 cm) zones had the lowest lichen species richness (5-13 species), followed by reference (unimpacted) and shallow (lichen species since 2012 while the light tephra and reference were essentially unchanged. Gravel rain, gravel rain + pumice and flooded forest plots all had about the same number of species in 2014 as 2012. Lichen colonization and growth in tree quadrats varied widely, from very little colonization in the blast to prolific colonization in the gravel rain + pumice zone. Lichen's varied responses to different volcanic disturbances were attributable to varying degrees of mortality and subsequent availability of substrate, quantity of light and removal of competitors. While sensitive to disturbance, lichens are apparently resilient to and can quickly recolonize after a variety of large, violent volcanic

  10. PIXE and NRA environmental studies by means of lichen indicators

    International Nuclear Information System (INIS)

    Hrynkiewicz, A.Z.; Szymczyk, S.; Kajfosz, J.; Olech, M.

    1980-01-01

    The trace element accumulating and integrating properties of epiphytic lichens were used for the study of air pollutions in Southern Poland. For the investigation of fluorine pollution by an aluminium plant the 19 F(p, p'γ) 19 F nuclear reaction, whereas for Pb and Br traffic pollution and heavy elements industrial pollution the PIXE method was used. The applicability of the lichen indicator method in environmental studies is discussed. (orig.)

  11. Esophageal Lichen Planus: Clinical and Radiographic Findings in Eight Patients.

    Science.gov (United States)

    Rauschecker, Andreas M; Levine, Marc S; Whitson, Matthew J; Tondon, Rashmi; Rubesin, Stephen E; Furth, Emma E; Metz, David C

    2017-01-01

    The purpose of this study is to present the clinical and radiographic findings of esophageal lichen planus. A search of computerized medical records identified 15 patients with pathologic findings of esophageal lichen planus on endoscopic biopsy specimens. Three other patients had presumed esophageal lichen planus, although no biopsy specimens were obtained. Twelve of these 18 patients (67%) had double-contrast esophagography performed at our institution; for eight of the 12 patients (67%), the studies revealed abnormalities in the esophagus. These eight patients constituted our study group. The barium esophagrams and medical records of these eight patients were reviewed to determine the clinical, radiographic, and endoscopic findings of esophageal lichen planus as well as the treatment and patient outcome. All eight patients were women (median age, 66.5 years), and all eight presented with dysphagia (mean duration, 3.2 years). Four patients had previous lichen planus that involved the skin (n = 1), the oral cavity (n = 2), or both (n = 1), and one patient later had lichen planus that involved the vagina. Five patients had a small-caliber esophagus with diffuse esophageal narrowing. The remaining three patients had segmental strictures in the cervical (n = 1), upper thoracic (n = 1), and distal thoracic (n = 1) esophagus. Esophageal lichen planus typically occurs in older women with longstanding dysphagia and often develops in the absence of extraesophageal disease. Barium esophagrams may reveal a small-caliber esophagus or, less commonly, segmental esophageal strictures. Greater awareness of the radiographic findings of esophageal lichen planus hopefully will lead to earlier diagnosis and better management of this condition.

  12. Lichen Planus Pigmentosus-like Reaction to Guasha.

    Science.gov (United States)

    Yang, Gang; Tan, Cheng

    2016-11-01

    Lichen planus pigmentosus (LPP) is an uncommon variant of lichen planus (LP) that manifests as macular hyperpigmentation involving chiefly the face and upper limbs. Although its etiology has not been fully elucidated, a relationship with hepatitis C infection, restrictive underwear, localized friction, and sun exposure have been proposed. Rarely, exposure to mustard oil, amla oil, henna, or hair dyes has been reported. We herein describe an LPP-like reaction to Guasha. © The Author(s) 2016.

  13. On The Etymology of Some Lichen Genera Names

    OpenAIRE

    Yavuz, Mustafa

    2016-01-01

    This study aims to investigate the etymology of some lichens’ genera names used in modern taxonomical botany. Growing on rocks, trees and even on soil, lichens are the only terrestrial cryptogamic organisms containing a fungal and an algal partner. Within this study, it has been focused to diagnose and improve an understanding of the similarities and differences between the names of lichen genera by comparing them in several languages. The etymological data collected during the study belongs ...

  14. Why Do Corals Bleach? Conflict and Conflict Mediation in a Host/Symbiont Community.

    Science.gov (United States)

    Blackstone, Neil W; Golladay, Jeff M

    2018-06-26

    Coral bleaching has attracted considerable study, yet one central question remains unanswered: given that corals and their Symbiodinium symbionts have co-evolved for millions of years, why does this clearly maladaptive process occur? Bleaching may result from evolutionary conflict between the host corals and their symbionts. Selection at the level of the individual symbiont favors using the products of photosynthesis for selfish replication, while selection at the higher level favors using these products for growth of the entire host/symbiont community. To hold the selfish lower-level units in check, mechanisms of conflict mediation must evolve. Fundamental features of photosynthesis have been co-opted into conflict mediation so that symbionts that fail to export these products produce high levels of reactive oxygen species and undergo programmed cell death. These mechanisms function very well under most environmental conditions, but under conditions particularly detrimental to photosynthesis, it is these mechanisms of conflict mediation that trigger bleaching. © 2018 WILEY Periodicals, Inc.

  15. Antioxidant, Antimicrobial and Antiproliferative Activities of Five Lichen Species

    Directory of Open Access Journals (Sweden)

    Snežana Marković

    2011-08-01

    Full Text Available The antioxidative, antimicrobial and antiproliferative potentials of the methanol extracts of the lichen species Parmelia sulcata, Flavoparmelia caperata, Evernia prunastri, Hypogymnia physodes and Cladonia foliacea were evaluated. The total phenolic content of the tested extracts varied from 78.12 to 141.59 mg of gallic acid equivalent (GA/g of extract and the total flavonoid content from 20.14 to 44.43 mg of rutin equivalent (Ru/g of extract. The antioxidant capacities of the lichen extracts were determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH radicals scavenging. Hypogymnia physodes with the highest phenolic content showed the strongest DPPH radical scavenging effect. Further, the antimicrobial potential of the lichen extracts was determined by a microdilution method on 29 microorganisms, including 15 strains of bacteria, 10 species of filamentous fungi and 4 yeast species. A high antimicrobial activity of all the tested extracts was observed with more potent inhibitory effects on the growth of Gram (+ bacteria. The highest antimicrobial activity among lichens was demonstrated by Hypogymnia physodes and Cladonia foliacea. Finally, the antiproliferative activity of the lichen extracts was explored on the colon cancer adenocarcinoma cell line HCT-116 by MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide viability assay and acridine orange/ethidium bromide staining. The methanol extracts of Hypogymnia physodes and Cladonia foliacea showed a better cytotoxic activity than the other extracts. All lichen species showed the ability to induce apoptosis of HCT-116 cells.

  16. Prion protein degradation by lichens of the genus Cladonia

    Science.gov (United States)

    Bennett, James P.; Rodriguez, Cynthia M.; Johnson, Christopher J.

    2012-01-01

    It has recently been discovered that lichens contain a serine protease capable of degrading the pathogenic prion protein, the etiological agent of prion diseases such as sheep scrapie and cervid chronic wasting disease. Limited methods are available to degrade or inactivate prion disease agents, especially in the environment, and lichens or their serine protease could prove important for management of these diseases. Scant information is available regarding the presence or absence of the protease responsible for degrading prion protein (PrP) in lichen species and, in this study, we tested the hypothesis that PrP degradation activity in lichens is phylogenetically-based by testing 44 species of Cladonia lichens, a genus for which a significant portion of the phylogeny is well established. We categorized PrP degradation activity among the 44 species (high, moderate, low or none) and found that activity in Cladonia species did not correspond with phylogenetic position of the species. Degradation of PrP did correspond, however, with three classical taxonomic characters within the genus: species with brown apothecia, no usnic acid, and the presence of a cortex. Of the 44 species studied, 18 (41%) had either high or moderate PrP degradation activity, suggesting the protease may be frequent in this genus of lichens.

  17. Lichen communities as bioindicators of the Aburra Valley air quality

    International Nuclear Information System (INIS)

    Jaramillo C, Margarita M; Botero B, Liliana R

    2010-01-01

    Lichens have been used as bioindicators of air quality. They are sensitive to changes in air composition at any given site affecting their abundance, biomass and vitality.This study evaluated lichen affectation as a consequence of air pollution. Two study areas within the Aburra Valley and the RedAire network were selected: Miguel Aguinaga (high pollution station) and the Medellin University (low pollution station). Four phorophytic tree species were chosen at each site Terminalia catappa Linneaus, Eritrina fusca Loureiro, Mangifera indica Linneaus y Fraxinus chinensis Roxb. The lichen cover by species, the vitality and the fructification were used to analyze the effect of air pollution. Finally, the lichen cover information was used to calculate the index of atmospheric purity (IAP) and the Q factor determination. Total qualitative and quantitative information obtained made evident that Canoparmelia sp. and Parmotrema austrosinensis (Zahlbr) Hale. lichen species are the most sensitive, and therefore appropriate to assess air quality. Additionally, the statistical analysis carried out using the relative abundances by phorophytic trees, showed that Fraxinus chinensis Roxb is the most appropriate tree species for bioindicator lichens studies into the Aburra valley.

  18. Antioxidant, Antimicrobial and Antiproliferative Activities of Five Lichen Species

    Science.gov (United States)

    Mitrović, Tatjana; Stamenković, Slaviša; Cvetković, Vladimir; Tošić, Svetlana; Stanković, Milan; Radojević, Ivana; Stefanović, Olgica; Čomić, Ljiljana; Đačić, Dragana; Ćurčić, Milena; Marković, Snežana

    2011-01-01

    The antioxidative, antimicrobial and antiproliferative potentials of the methanol extracts of the lichen species Parmelia sulcata, Flavoparmelia caperata, Evernia prunastri, Hypogymnia physodes and Cladonia foliacea were evaluated. The total phenolic content of the tested extracts varied from 78.12 to 141.59 mg of gallic acid equivalent (GA)/g of extract and the total flavonoid content from 20.14 to 44.43 mg of rutin equivalent (Ru)/g of extract. The antioxidant capacities of the lichen extracts were determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals scavenging. Hypogymnia physodes with the highest phenolic content showed the strongest DPPH radical scavenging effect. Further, the antimicrobial potential of the lichen extracts was determined by a microdilution method on 29 microorganisms, including 15 strains of bacteria, 10 species of filamentous fungi and 4 yeast species. A high antimicrobial activity of all the tested extracts was observed with more potent inhibitory effects on the growth of Gram (+) bacteria. The highest antimicrobial activity among lichens was demonstrated by Hypogymnia physodes and Cladonia foliacea. Finally, the antiproliferative activity of the lichen extracts was explored on the colon cancer adenocarcinoma cell line HCT-116 by MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) viability assay and acridine orange/ethidium bromide staining. The methanol extracts of Hypogymnia physodes and Cladonia foliacea showed a better cytotoxic activity than the other extracts. All lichen species showed the ability to induce apoptosis of HCT-116 cells. PMID:21954369

  19. Salivary proteomics in lichen planus: A relationship with pathogenesis?

    Science.gov (United States)

    Souza, M M; Florezi, G P; Nico, Mms; de Paula, F; Paula, F M; Lourenço, S V

    2018-01-30

    Oral lichen planus is a chronic, T-cell-mediated, inflammatory disease that affects the oral cavity. The oral lichen planus pathogenesis is still unclear, however, the main evidence is that the mechanisms of activation of different T lymphocyte pathway induce apoptosis with an increase in Th1 and Th17 subtypes cells, triggered by the release of cytokines. This study analysed saliva proteomics to identify protein markers that might be involved in the pathogenesis and development of the disease. Proteins differentially expressed by oral lichen planus and healthy controls were screened using mass spectrometry; the proteins found in oral lichen planus were subjected to bioinformatics analysis, including gene ontology and string networks analysis. The multiplex analysis validation allowed the correlation between the proteins identified and the involved cytokines in Th17 response. One hundred and eight proteins were identified in oral lichen planus, of which 17 proteins showed a high interaction between them and indicated an association with the disease. Expression of these proteins was correlated with the triggering of cytokines, more specifically the Th17 cells. Proteins, such as S100A8, S100A9, haptoglobin, can trigger cytokines and might be associated with a pathological function and antioxidant activities in oral lichen planus. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd. All rights reserved.

  20. VCAM1 and ICAM1 expression in oral lichen planus

    Science.gov (United States)

    Seyedmajidi, Maryam; Shafaee, Shahryar; Bijani, Ali; Bagheri, Soodabeh

    2013-01-01

    Oral lichen planus is a chronic inflammatory immune-mediated disease. ICAM-1 and VCAM-1 are vascular adhesion molecules that their receptors are located on endothelial cells and leukocytes. The aim of this study is the immunohistochemical evaluation of VCAM1 and ICAM1 in oral lichen planus and to compare these two markers with normal mucosa for evaluation of angiogenesis. This descriptive-analytical study was performed on 70 paraffined blocks of oral lichen planus and 30 normal mucosa samples taken from around the lesions. Samples were stained with H & E and then with Immunohistochemistry using monoclonal mouse anti human VCAM1 (CD106), & monoclonal mouse anti human ICAM1(CD54) for confirmation of diagnosis. Slides were evaluated under light microscope and VCAM1 and ICAM1 positive cells (endothelial cells and leukocytes) were counted. Data were analyzed with Mann-Whitney test, Wilcoxon and Chi-Square and poral lichen planus according to the percentage of stained cells (p=0.000& p=0.000, Mann-Whitney test). Thirty cases of oral normal mucosa associated with lichen planus showed that the VCAM1 has increased significantly in comparison to normal mucosa (plichen planus and normal mucosa, showed a significantly difference (plichen planus was not observed (p>0.05). Regarding the results, it seems that high expression of VCAM1 and ICAM1 is related to oral lichen planus. PMID:24551788

  1. Littoral lichens as a novel source of potentially bioactive Actinobacteria.

    Science.gov (United States)

    Parrot, Delphine; Antony-Babu, Sanjay; Intertaglia, Laurent; Grube, Martin; Tomasi, Sophie; Suzuki, Marcelino T

    2015-10-30

    Cultivable Actinobacteria are the largest source of microbially derived bioactive molecules. The high demand for novel antibiotics highlights the need for exploring novel sources of these bacteria. Microbial symbioses with sessile macro-organisms, known to contain bioactive compounds likely of bacterial origin, represent an interesting and underexplored source of Actinobacteria. We studied the diversity and potential for bioactive-metabolite production of Actinobacteria associated with two marine lichens (Lichina confinis and L. pygmaea; from intertidal and subtidal zones) and one littoral lichen (Roccella fuciformis; from supratidal zone) from the Brittany coast (France), as well as the terrestrial lichen Collema auriforme (from a riparian zone, Austria). A total of 247 bacterial strains were isolated using two selective media. Isolates were identified and clustered into 101 OTUs (98% identity) including 51 actinobacterial OTUs. The actinobacterial families observed were: Brevibacteriaceae, Cellulomonadaceae, Gordoniaceae, Micrococcaceae, Mycobacteriaceae, Nocardioidaceae, Promicromonosporaceae, Pseudonocardiaceae, Sanguibacteraceae and Streptomycetaceae. Interestingly, the diversity was most influenced by the selective media rather than lichen species or the level of lichen thallus association. The potential for bioactive-metabolite biosynthesis of the isolates was confirmed by screening genes coding for polyketide synthases types I and II. These results show that littoral lichens are a source of diverse potentially bioactive Actinobacteria.

  2. Lichens and lichenicolous fungi from the Retezat Mts and overlooked records for the checklist of Romanian lichens

    Czech Academy of Sciences Publication Activity Database

    Vondrák, Jan; Liška, Jiří

    2013-01-01

    Roč. 26, č. 2 (2013), s. 293-305 ISSN 0018-0971 Institutional support: RVO:67985939 Keywords : biodiversity * Carpathians * lichenized fungi Subject RIV: EF - Botanics Impact factor: 0.919, year: 2013

  3. A Novel, Extremely Elongated, and Endocellular Bacterial Symbiont Supports Cuticle Formation of a Grain Pest Beetle

    Directory of Open Access Journals (Sweden)

    Bin Hirota

    2017-09-01

    Full Text Available The saw-toothed grain beetle, Oryzaephilus surinamensis (Silvanidae, is a cosmopolitan stored-product pest. Early studies on O. surinamensis in the 1930s described the presence of peculiar bacteriomes harboring endosymbiotic bacteria in the abdomen. Since then, however, the microbiological nature of the symbiont has been elusive. Here we investigated the endosymbiotic system of O. surinamensis in detail. In the abdomen of adults, pupae, and larvae, four oval bacteriomes were consistently identified, whose cytoplasm was full of extremely elongated tubular bacterial cells several micrometers wide and several hundred micrometers long. Molecular phylogenetic analysis identified the symbiont as a member of the Bacteroidetes, in which the symbiont was the most closely related to the endosymbiont of a grain pest beetle, Rhyzopertha dominica (Bostrichidae. The symbiont was detected in developing embryos, corroborating vertical symbiont transmission through host generations. The symbiont gene showed AT-biased nucleotide composition and accelerated molecular evolution, plausibly reflecting degenerative evolution of the symbiont genome. When the symbiont infection was experimentally removed, the aposymbiotic insects grew and reproduced normally, but exhibited a slightly but significantly more reddish cuticle and lighter body mass. These results indicate that the symbiont of O. surinamensis is not essential for the host’s growth and reproduction but contributes to the host’s cuticle formation. Symbiont genome sequencing and detailed comparison of fitness parameters between symbiotic and aposymbiotic insects under various environmental conditions will provide further insights into the symbiont’s biological roles for the stored-product pest.

  4. Anemone bleaching increases the metabolic demands of symbiont anemonefish.

    Science.gov (United States)

    Norin, Tommy; Mills, Suzanne C; Crespel, Amélie; Cortese, Daphne; Killen, Shaun S; Beldade, Ricardo

    2018-04-11

    Increased ocean temperatures are causing mass bleaching of anemones and corals in the tropics worldwide. While such heat-induced loss of algal symbionts (zooxanthellae) directly affects anemones and corals physiologically, this damage may also cascade on to other animal symbionts. Metabolic rate is an integrative physiological trait shown to relate to various aspects of organismal performance, behaviour and locomotor capacity, and also shows plasticity during exposure to acute and chronic stressors. As climate warming is expected to affect the physiology, behaviour and life history of animals, including ectotherms such as fish, we measured if residing in bleached versus unbleached sea anemones ( Heteractis magnifica ) affected the standard (i.e. baseline) metabolic rate and behaviour (activity) of juvenile orange-fin anemonefish ( Amphiprion chrysopterus ) . Metabolic rate was estimated from rates of oxygen uptake [Formula: see text], and the standard metabolic rate [Formula: see text] of anemonefish from bleached anemones was significantly higher by 8.2% compared with that of fish residing in unbleached anemones, possibly due to increased stress levels. Activity levels did not differ between fish from bleached and unbleached anemones. As [Formula: see text] reflects the minimum cost of living, the increased metabolic demands may contribute to the negative impacts of bleaching on important anemonefish life history and fitness traits observed previously (e.g. reduced spawning frequency and lower fecundity). © 2018 The Author(s).

  5. Standing genetic variation in host preference for mutualist microbial symbionts.

    Science.gov (United States)

    Simonsen, Anna K; Stinchcombe, John R

    2014-12-22

    Many models of mutualisms show that mutualisms are unstable if hosts lack mechanisms enabling preferential associations with mutualistic symbiotic partners over exploitative partners. Despite the theoretical importance of mutualism-stabilizing mechanisms, we have little empirical evidence to infer their evolutionary dynamics in response to exploitation by non-beneficial partners. Using a model mutualism-the interaction between legumes and nitrogen-fixing soil symbionts-we tested for quantitative genetic variation in plant responses to mutualistic and exploitative symbiotic rhizobia in controlled greenhouse conditions. We found significant broad-sense heritability in a legume host's preferential association with mutualistic over exploitative symbionts and selection to reduce frequency of associations with exploitative partners. We failed to detect evidence that selection will favour the loss of mutualism-stabilizing mechanisms in the absence of exploitation, as we found no evidence for a fitness cost to the host trait or indirect selection on genetically correlated traits. Our results show that genetic variation in the ability to preferentially reduce associations with an exploitative partner exists within mutualisms and is under selection, indicating that micro-evolutionary responses in mutualism-stabilizing traits in the face of rapidly evolving mutualistic and exploitative symbiotic bacteria can occur in natural host populations. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  6. Effect of airborne fluorides on lichens

    Energy Technology Data Exchange (ETDEWEB)

    Gilbert, O L

    1971-01-01

    There are sound reasons for believing that the small lichen and bryophyte desert discovered round the aluminium works at Fort William is caused by fluorides escaping from the factory. By virtue of furnace design changes and the installation of fume treatment plant, the amount released is now much lower than it was in 1936, but recent analysis of plant material shows that the area is still heavily contaminated. The desert differs in several ways from those caused by SO/sub 2/. Throughout it and the transition zone, damage to the leaves and young growth of woody plants is a conspicuous feature. Near its middle certain coniferous trees, for example Pinus sylvestris and Pseudotsuga taxifolia, are unable to grow, and all forest trees are dwarfed and scrublike. 7 references, 1 figure, 1 table.

  7. Oral lichen planus and stress: An appraisal

    Directory of Open Access Journals (Sweden)

    Simarpreet V Sandhu

    2014-01-01

    Full Text Available Introduction: Oral lichen planus (OLP is a chronic inflammatory disease characterized by bilateral white striations or plaques on the buccal mucosa, tongue or gingiva that has a multifactorial etiology, where the psychogenic factors seem to play an important role. Purpose: The aim of this study was to determine the existing relation between the OLP and psychological alterations of the patient, such as stress, anxiety, and depression. Materials and Methods: Hospital anxiety and depression scale was applied for psychometric analysis. Results: The study indicates a definitive relationship between a stressful life event and onset and progression of OLP. Conclusion: Stress management and bereavement counseling should be a part of management protocol of OLP.

  8. Hyperkeratotic palmoplantar lichen planus in a child

    Directory of Open Access Journals (Sweden)

    Bhushan Madke

    2013-01-01

    Full Text Available Lichen planus (LP is a common idiopathic inflammatory disorder that affects the flexor aspect of the wrists, the legs, and the oral and genital mucosa. Depending upon the site of involvement, LP can be divided into mucosal, nail, scalp, or palmoplantar types. Palmoplantar LP can pose a diagnostic problem to the clinician as it resembles common dermatoses like psoriasis, verruca, corn, calluses, lichenoid drug eruption, and papular syphilide of secondary syphilis. In this case report, we describe a 4-year-old male child who presented with highly pruritic erythematous to violaceous hyperkeratotic papules and plaques on his palms and soles. Typical LP papules were noted on the upper back. Histopathology of the papular lesion showed features of LP. Dermatoscopy of a papule from the back showed the characteristic Wickham striae. We report this rare involvement of palm and soles in a case of childhood LP.

  9. Histamine H4 receptor in oral lichen planus.

    Science.gov (United States)

    Salem, A; Al-Samadi, A; Stegajev, V; Stark, H; Häyrinen-Immonen, R; Ainola, M; Hietanen, J; Konttinen, Y T

    2015-04-01

    Oral lichen planus (OLP) is an autoimmune disease characterized by a band-like T-cell infiltrate below the apoptotic epithelial cells and degenerated basement membrane. We tested the hypothesis that the high-affinity histamine H4 receptors (H4 Rs) are downregulated in OLP by high histamine concentrations and proinflammatory T-cell cytokines. Immunohistochemistry and immunofluorescence staining, image analysis and quantitative real-time polymerase chain reaction of tissue samples and cytokine-stimulated cultured SCC-25 and primary human oral keratinocytes. H4 R immunoreactivity was weak in OLP and characterized by mast cell (MC) hyperplasia and degranulation. In contrast to controls, H4 R immunostaining and MC counts were negatively correlated in OLP (P = 0.003). H4 R agonist at nanomolar levels led to a rapid internalization of H4 Rs, whereas high histamine concentration and interferon-γ decreased HRH4 -gene transcripts. Healthy oral epithelial cells are equipped with H4 R, which displays a uniform staining pattern in a MC-independent fashion. In contrast, in OLP, increased numbers of activated MCs associate with increasing loss of epithelial H4 R. Cell culture experiments suggest a rapid H4 R stimulation-dependent receptor internalization and a slow cytokine-driven decrease in H4 R synthesis. H4 R may be involved in the maintenance of healthy oral mucosa. In OLP, this maintenance might be impaired by MC degranulation and inflammatory cytokines. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  10. Contrasting calcification responses to ocean acidification between two reef foraminifers harboring different algal symbionts

    Science.gov (United States)

    Hikami, Mana; Ushie, Hiroyuki; Irie, Takahiro; Fujita, Kazuhiko; Kuroyanagi, Azumi; Sakai, Kazuhiko; Nojiri, Yukihiro; Suzuki, Atsushi; Kawahata, Hodaka

    2011-10-01

    Ocean acidification, which like global warming is an outcome of anthropogenic CO2 emissions, severely impacts marine calcifying organisms, especially those living in coral reef ecosystems. However, knowledge about the responses of reef calcifiers to ocean acidification is quite limited, although coral responses are known to be generally negative. In a culture experiment with two algal symbiont-bearing, reef-dwelling foraminifers, Amphisorus kudakajimensis and Calcarina gaudichaudii, in seawater under five different pCO2 conditions, 245, 375, 588, 763 and 907 μatm, maintained with a precise pCO2-controlling technique, net calcification of A. kudakajimensis was reduced under higher pCO2, whereas calcification of C. gaudichaudii generally increased with increased pCO2. In another culture experiment conducted in seawater in which bicarbonate ion concentrations were varied under a constant carbonate ion concentration, calcification was not significantly different between treatments in Amphisorus hemprichii, a species closely related to A. kudakajimensis, or in C. gaudichaudii. From these results, we concluded that carbonate ion and CO2 were the carbonate species that most affected growth of Amphisorus and Calcarina, respectively. The opposite responses of these two foraminifer genera probably reflect different sensitivities to these carbonate species, which may be due to their different symbiotic algae.

  11. Photobiont diversity in lichens from metal-rich substrata based on ITS rDNA sequences.

    Science.gov (United States)

    Backor, Martin; Peksa, Ondrej; Skaloud, Pavel; Backorová, Miriam

    2010-05-01

    The photobiont is considered as the more sensitive partner of lichen symbiosis in metal pollution. For this reason the presence of a metal tolerant photobiont in lichens may be a key factor of ecological success of lichens growing on metal polluted substrata. The photobiont inventory was examined for terricolous lichen community growing in Cu mine-spoil heaps derived by historical mining. Sequences of internal transcribed spacer (ITS) were phylogenetically analyzed using maximum likelihood analyses. A total of 50 ITS algal sequences were obtained from 22 selected lichen taxa collected at three Cu mine-spoil heaps and two control localities. Algae associated with Cladonia and Stereocaulon were identified as members of several Asterochloris lineages, photobionts of cetrarioid lichens clustered with Trebouxia hypogymniae ined. We did not find close relationship between heavy metal content (in localities as well as lichen thalli) and photobiont diversity. Presence of multiple algal genotypes in single lichen thallus has been confirmed. Copyright 2009 Elsevier Inc. All rights reserved.

  12. Estimation of arboreal lichen biomass available to woodland caribou in Hudson Bay lowland black spruce sites

    Directory of Open Access Journals (Sweden)

    Sarah K. Proceviat

    2003-04-01

    Full Text Available An arboreal lichen index to be utilized in assessing woodland caribou habitat throughout northeastern Ontario was developed. The "index" was comprised of 5 classes, which differentiated arboreal lichen biomass on black spruce trees, ranging from maximal quantities of arboreal lichen (class 5 to minimal amounts of arboreal lichen (class 1. This arboreal lichen index was subsequently used to estimate the biomass of arboreal lichen available to woodland caribou on lowland black spruce sites ranging in age from 1 year to 150 years post-harvest. A total of 39 sites were assessed and significant differences in arboreal lichen biomass were found, with a positive linear relationship between arboreal lichen biomass and forest age. It is proposed that the index be utilized by government and industry as a means of assessing the suitability of lowland black spruce habitat for woodland caribou in this region.

  13. Host-symbiont co-speciation and reductive genome evolution in gut symbiotic bacteria of acanthosomatid stinkbugs

    Directory of Open Access Journals (Sweden)

    Kamagata Yoichi

    2009-01-01

    Full Text Available Abstract Background Host-symbiont co-speciation and reductive genome evolution have been commonly observed among obligate endocellular insect symbionts, while such examples have rarely been identified among extracellular ones, the only case reported being from gut symbiotic bacteria of stinkbugs of the family Plataspidae. Considering that gut symbiotic communities are vulnerable to invasion of foreign microbes, gut symbiotic associations have been thought to be evolutionarily not stable. Stinkbugs of the family Acanthosomatidae harbor a bacterial symbiont in the midgut crypts, the lumen of which is completely sealed off from the midgut main tract, thereby retaining the symbiont in the isolated cryptic cavities. We investigated histological, ecological, phylogenetic, and genomic aspects of the unique gut symbiosis of the acanthosomatid stinkbugs. Results Phylogenetic analyses showed that the acanthosomatid symbionts constitute a distinct clade in the γ-Proteobacteria, whose sister groups are the obligate endocellular symbionts of aphids Buchnera and the obligate gut symbionts of plataspid stinkbugs Ishikawaella. In addition to the midgut crypts, the symbionts were located in a pair of peculiar lubricating organs associated with the female ovipositor, by which the symbionts are vertically transmitted via egg surface contamination. The symbionts were detected not from ovaries but from deposited eggs, and surface sterilization of eggs resulted in symbiont-free hatchlings. The symbiont-free insects suffered retarded growth, high mortality, and abnormal morphology, suggesting important biological roles of the symbiont for the host insects. The symbiont phylogeny was generally concordant with the host phylogeny, indicating host-symbiont co-speciation over evolutionary time despite the extracellular association. Meanwhile, some local host-symbiont phylogenetic discrepancies were found, suggesting occasional horizontal symbiont transfers across the host

  14. Clinical and Laboratory Findings of a Group of Iranian Patients with Oral Lichen Planus

    OpenAIRE

    Darvishpoor Kakhki H.; Rad M.; Zarei MR.; Chamani G.

    2012-01-01

    atement of Problem: Lichen planus (LP) is a chronic disease that affects skin and mucous membranes. Lesions of oral lichen planus (OLP) can persist for a long time. Varying prevalence rates of oral lichen planus have been reported in different parts of the world, while information regarding the epidemiology of this disease in Iran is incomplete.Purpose: This study was designed to evaluate the characteristics of oral lichen planus in a group of Iranian patients and compare the results with sim...

  15. A model for analyzing influence of timber production on lichens for reindeer grazing

    OpenAIRE

    Eriksson, Olof; Sandewall, Mats; Wilhelmsson, Erik

    1987-01-01

    A model for long-term analysis of the influence of timber production on lichens for reindeer grazing (Cladina, Alectoria, Bryoria spp and others) in Sweden is presented. The annual production of and demand for lichens are estimated and compared. Production of these lichens is presumed to set the upper limit for the reindeer population. Reindeer graze on both ground and tree lichens, which both must be accessible in sufficient amounts and at the right times of the year if reindeer husbandry is...

  16. Taxonomic identity and physiological ecology of Chlamydomonas hedleyi sp. nov. , algal flagellate symbiont from the foraminifer Archaias angulatus

    Energy Technology Data Exchange (ETDEWEB)

    Lee, J J; Crockett, L J; Hagen, J; Stone, R J

    1975-12-31

    The fine structure of the symbiotic alga isolated from the foraminiferan Archaias angulatus (Fichtel et Moll) DeMontfort is typical of the Chlorophyceae of the volvocalean and chlorococcalean lines. Spherical non-motile cells, 10--14 ..mu..m in diameter, characterize the dominant life cycle phase. Long oval motile forms with truncated apices are present 3--5 days after transfer to fresh medium. The pyrenoids are embedded anteriorly in the singly bilobed chloroplast and are surrounded by a sheath of starch platelets. In spite of the non-motile state of cells in older cultures (which is perhaps a reflection of its normally symbiotic condition), the alga is identified as a species of the volvocalean genus Chlamydomonas and is named C. hedleyi sp. nov. The symbiont has no vitamin or organic requirements but growth is increased threefold in the presence of thiamine, and twofold in the presence of 1 ..mu..m glutamic acid, histidine and methionine. Urea was the best nitrogen source tested. Purines and pyrimidines did not serve as nitrogen sources. Chlamydomonas hedleyi grows well in a salinity range of 6- greater than 52 per thousand and a pH range of 6--8.5. 7.04 x 10/sup -7/ M carbon h/sup -1/ g/sup -1/ was fixed by the symbiont, 57 percent being released into the medium as a chromatographically homogeneous organic molecule provisionally identified as mannitol.

  17. Fungal Volatiles Can Act as Carbon Sources and Semiochemicals to Mediate Interspecific Interactions Among Bark Beetle-Associated Fungal Symbionts.

    Directory of Open Access Journals (Sweden)

    Jonathan A Cale

    Full Text Available Mountain pine beetle (Dendroctonus ponderosae has killed millions of hectares of pine forests in western North America. Beetle success is dependent upon a community of symbiotic fungi comprised of Grosmannia clavigera, Ophiostoma montium, and Leptographium longiclavatum. Factors regulating the dynamics of this community during pine infection are largely unknown. However, fungal volatile organic compounds (FVOCs help shape fungal interactions in model and agricultural systems and thus may be important drivers of interactions among bark beetle-associated fungi. We investigated whether FVOCs can mediate interspecific interactions among mountain pine beetle's fungal symbionts by affecting fungal growth and reproduction. Headspace volatiles were collected and identified to determine species-specific volatile profiles. Interspecific effects of volatiles on fungal growth and conidia production were assessed by pairing physically-separated fungal cultures grown either on a carbon-poor or -rich substrate, inside a shared-headspace environment. Fungal VOC profiles differed by species and influenced the growth and/or conidia production of the other species. Further, our results showed that FVOCs can be used as carbon sources for fungi developing on carbon-poor substrates. This is the first report demonstrating that FVOCs can drive interactions among bark beetle fungal symbionts, and thus are important factors in beetle attack success.

  18. Air biomonitoring by transplanted lichens in the Negev Desert, Israel

    International Nuclear Information System (INIS)

    Garty, J.

    1999-01-01

    Thalli of the lichen Ramalina maciformis (Del.) Bory were collected in the Negev Desert in August 1997 and transplanted with their substrate, flintstones, to 24 bio-monitoring sites in the Negev Desert. An assessment of the impact of anthropogenic activities was made by measurements of the concentration of mineral elements in the lichen and by an examination of its physiological status. After a transplantation period of nine months, the lichens were retrieved in April 1998 and the concentration of 22 mineral elements in the thallus was determined by ICP-AES. In addition we examined the following parameters determining the status of the lichen: 1. Electric conductivity indicative of cell membrane integrity; 2. Spectral reflectance response of the thallus expressed as normalized difference vegetation index (NDVI) indicative of greenness and health of the thallus; 3. Production of ethylene indicative of stress, 4. Chlorophyll a fluorescence as a means to monitor aspects of photosystem II (PSII) activities in the lichen. Preliminary results show that lichens exposed to air contaminants at a site of toxic waste deposition contain high concentrations of Ca, Cu, Pb and Mn and significant low K concentrations due to leakage of this element from injured cell membranes. Conductivity measurements performed to test the integrity of cell membranes corroborated this assumption. NDVI values indicating damage to chlorophyll were relative low in lichens retrieved from sites near Beer Sheba. The stress-ethylene production was the highest in one site near Beer Sheba. The maximum quantum yield of PSII expressed as fluorescence ratio Fv/Fm was low in two sites in the Ramat Hovav Industrial Area. (author)

  19. Air biomonitoring by transplanted lichens in the Negev Desert, Israel

    Energy Technology Data Exchange (ETDEWEB)

    Garty, J [Department of Plant Sciences and Institute for Nature Conservation Research, Tel Aviv University, Tel Aviv (Israel)

    1999-07-01

    Thalli of the lichen Ramalina maciformis (Del.) Bory were collected in the Negev Desert in August 1997 and transplanted with their substrate, flintstones, to 24 bio-monitoring sites in the Negev Desert. An assessment of the impact of anthropogenic activities was made by measurements of the concentration of mineral elements in the lichen and by an examination of its physiological status. After a transplantation period of nine months, the lichens were retrieved in April 1998 and the concentration of 22 mineral elements in the thallus was determined by ICP-AES. In addition we examined the following parameters determining the status of the lichen: 1. Electric conductivity indicative of cell membrane integrity; 2. Spectral reflectance response of the thallus expressed as normalized difference vegetation index (NDVI) indicative of greenness and health of the thallus; 3. Production of ethylene indicative of stress, 4. Chlorophyll a fluorescence as a means to monitor aspects of photosystem II (PSII) activities in the lichen. Preliminary results show that lichens exposed to air contaminants at a site of toxic waste deposition contain high concentrations of Ca, Cu, Pb and Mn and significant low K concentrations due to leakage of this element from injured cell membranes. Conductivity measurements performed to test the integrity of cell membranes corroborated this assumption. NDVI values indicating damage to chlorophyll were relative low in lichens retrieved from sites near Beer Sheba. The stress-ethylene production was the highest in one site near Beer Sheba. The maximum quantum yield of PSII expressed as fluorescence ratio Fv/Fm was low in two sites in the Ramat Hovav Industrial Area. (author)

  20. Surfing the vegetal pole in a small population: extracellular vertical transmission of an 'intracellular' deep-sea clam symbiont.

    Science.gov (United States)

    Ikuta, Tetsuro; Igawa, Kanae; Tame, Akihiro; Kuroiwa, Tsuneyoshi; Kuroiwa, Haruko; Aoki, Yui; Takaki, Yoshihiro; Nagai, Yukiko; Ozawa, Genki; Yamamoto, Masahiro; Deguchi, Ryusaku; Fujikura, Katsunori; Maruyama, Tadashi; Yoshida, Takao

    2016-05-01

    Symbiont transmission is a key event for understanding the processes underlying symbiotic associations and their evolution. However, our understanding of the mechanisms of symbiont transmission remains still fragmentary. The deep-sea clam Calyptogena okutanii harbours obligate sulfur-oxidizing intracellular symbiotic bacteria in the gill epithelial cells. In this study, we determined the localization of their symbiont associating with the spawned eggs, and the population size of the symbiont transmitted via the eggs. We show that the symbionts are located on the outer surface of the egg plasma membrane at the vegetal pole, and that each egg carries approximately 400 symbiont cells, each of which contains close to 10 genomic copies. The very small population size of the symbiont transmitted via the eggs might narrow the bottleneck and increase genetic drift, while polyploidy and its transient extracellular lifestyle might slow the rate of genome reduction. Additionally, the extracellular localization of the symbiont on the egg surface may increase the chance of symbiont exchange. This new type of extracellular transovarial transmission provides insights into complex interactions between the host and symbiont, development of both host and symbiont, as well as the population dynamics underlying genetic drift and genome evolution in microorganisms.

  1. Tracking polycyclic aromatic hydrocarbons in lichens: It's all about the algae

    International Nuclear Information System (INIS)

    Augusto, Sofia; Sierra, Jordi; Nadal, Martí; Schuhmacher, Marta

    2015-01-01

    Lichens, symbioses of fungi and algae and/or cyanobacteria, have the remarkable ability to uptake and accumulate semivolatile organic compounds (SVOC) from air, including polycyclic aromatic hydrocarbons (PAHs), but the mechanism of accumulation is still unknown. Understanding these mechanisms is critical to standardize the use of lichens as environmental bioindicators and to further integrate them in air monitoring networks. Through a series of experiments we show that gas phase PAHs easily cross lichen's surface and accumulate in the photosynthetic algal layer of lichens. Once accumulated, they remain in the algal layer and not within the fungus hyphae, or adhered to lichen's surface, as it was previously supposed to happen. Additionally, when lichens are washed, gas phase PAHs still remain in the algal layer. Our results reveal that lichens may be utilized as bioindicators of gas phase PAHs, overcoming current limitations of air monitoring. - Highlights: • Gas phase PAHs accumulate in the photosynthetic algal layer of lichens. • When lichens are washed by rain, gas phase PAHs remain in the algal layer. • Algae content may be a source of variability when interpreting PAH data in lichens. - Gas phase PAHs easily cross lichen's surface and accumulate in the photosynthetic algal layer of lichens.

  2. Lichen Monitoring Delineates Biodiversity on a Great Barrier Reef Coral Cay

    Directory of Open Access Journals (Sweden)

    Paul C. Rogers

    2015-05-01

    Full Text Available Coral islands around the world are threatened by changing climates. Rising seas, drought, and increased tropical storms are already impacting island ecosystems. We aim to better understand lichen community ecology of coral island forests. We used an epiphytic lichen community survey to gauge Pisonia (Pisonia grandis R.BR., which dominates forest conditions on Heron Island, Australia. Nine survey plots were sampled for lichen species presence and abundance, all tree diameters and species, GPS location, distance to forest-beach edge, and dominant forest type. Results found only six unique lichens and two lichen associates. A Multi-Response Permutation Procedures (MRPP test found statistically distinct lichen communities among forest types. The greatest group differences were between interior Pisonia and perimeter forest types. Ordinations were performed to further understand causes for distinctions in lichen communities. Significant explanatory gradients were distance to forest edge, tree density (shading, and Pisonia basal area. Each of these variables was negatively correlated with lichen diversity and abundance, suggesting that interior, successionally advanced, Pisonia forests support fewer lichens. Island edge and presumably younger forests—often those with greater tree diversity and sunlight penetration—supported the highest lichen diversity. Heron Island’s Pisonia-dominated forests support low lichen diversity which mirrors overall biodiversity patterns. Lichen biomonitoring may provide a valuable indicator for assessing island ecosystems for conservation purposes regionally.

  3. The lichen genus Caloplaca (Ascomycota, Lecanoromycetes) on Svalbard. Notes and additions

    DEFF Research Database (Denmark)

    Søchting, Ulrik; Lorentsen, Line Balschmidt; Arup, Ulf

    2008-01-01

    23 species of the lichen genus Caloplaca from Svalbard are described and/or discussed. The descriptions are natural language descriptions based on characters for each species coded into LIAS (Global Information System for Lichenized and Non-Lichenized Ascomycetes). A total of 37 Caloplaca species...

  4. Lichen communities and species indicate climate thresholds in southeast and south-central Alaska, USA

    Science.gov (United States)

    Heather T. Root; Bruce. McCune; Sarah. Jovan

    2014-01-01

    Because of their unique physiology, lichen communities are highly sensitive to climatic conditions,making them ideal bioindicators for climate change. Southeast and south-central Alaska host diverse and abundant lichen communities and are faced with a more rapidly changing climate than many more southerly latitudes. We develop sensitive lichen-based indicators for...

  5. Canaries in a coal mine: using lichens to measure nitrogen pollution

    Science.gov (United States)

    Marie Oliver; Linda Geiser; Sarah Jovan

    2011-01-01

    In Pacific Northwest forests, lichens provide essential winter forage for deer and elk and also nesting materials and habitat for rodents, birds, and invertebrates. Although lichens are often the first organisms to populate a landscape and many species can survive in the most barren environments, lichens with the greatest ecological value tend to be the most sensitive...

  6. Dynamics of species diversity of epiphytic lichenized fungi in the southern district of Moscow city

    Directory of Open Access Journals (Sweden)

    Biazrov Lev

    2013-03-01

    2006-2007 on the same territory the representatives of 54 epiphytic lichen species were found. The basic reason of the changes in the compositionof lichen biota revealed on the studied urban territory is eutrophication mainly nitrophication of lichen habitats in Moscow city."

  7. Two siblings with lichen planus and squamous cell carcinoma of the oesophagus

    NARCIS (Netherlands)

    Schwartz, Matthijs P.; Sigurdsson, Vigfus; Vreuls, Willem; Lubbert, Pieter H. W.; Smout, André J. P. M.

    2006-01-01

    Lichen planus is a mucocutaneous disease which can also affect the oesophagus. Unlike in oral lichen planus an increased risk for the development of squamous cell carcinoma in the oesophagus has not been established. We describe two sisters with a history of long-standing cutaneous lichen planus who

  8. Primates, Lice and Bacteria: Speciation and Genome Evolution in the Symbionts of Hominid Lice.

    Science.gov (United States)

    Boyd, Bret M; Allen, Julie M; Nguyen, Nam-Phuong; Vachaspati, Pranjal; Quicksall, Zachary S; Warnow, Tandy; Mugisha, Lawrence; Johnson, Kevin P; Reed, David L

    2017-07-01

    Insects with restricted diets rely on symbiotic bacteria to provide essential metabolites missing in their diet. The blood-sucking lice are obligate, host-specific parasites of mammals and are themselves host to symbiotic bacteria. In human lice, these bacterial symbionts supply the lice with B-vitamins. Here, we sequenced the genomes of symbiotic and heritable bacterial of human, chimpanzee, gorilla, and monkey lice and used phylogenomics to investigate their evolutionary relationships. We find that these symbionts have a phylogenetic history reflecting the louse phylogeny, a finding contrary to previous reports of symbiont replacement. Examination of the highly reduced symbiont genomes (0.53-0.57 Mb) reveals much of the genomes are dedicated to vitamin synthesis. This is unchanged in the smallest symbiont genome and one that appears to have been reorganized. Specifically, symbionts from human lice, chimpanzee lice, and gorilla lice carry a small plasmid that encodes synthesis of vitamin B5, a vitamin critical to the bacteria-louse symbiosis. This plasmid is absent in an old world monkey louse symbiont, where this pathway is on its primary chromosome. This suggests the unique genomic configuration brought about by the plasmid is not essential for symbiosis, but once obtained, it has persisted for up to 25 My. We also find evidence that human, chimpanzee, and gorilla louse endosymbionts have lost a pathway for synthesis of vitamin B1, whereas the monkey louse symbiont has retained this pathway. It is unclear whether these changes are adaptive, but they may point to evolutionary responses of louse symbionts to shifts in primate biology. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  9. Patterns of interaction specificity of fungus-growing termites and Termitomyces symbionts in South Africa

    Directory of Open Access Journals (Sweden)

    de Beer Z Wilhelm

    2007-07-01

    Full Text Available Abstract Background Termites of the subfamily Macrotermitinae live in a mutualistic symbiosis with basidiomycete fungi of the genus Termitomyces. Here, we explored interaction specificity in fungus-growing termites using samples from 101 colonies in South-Africa and Senegal, belonging to eight species divided over three genera. Knowledge of interaction specificity is important to test the hypothesis that inhabitants (symbionts are taxonomically less diverse than 'exhabitants' (hosts and to test the hypothesis that transmission mode is an important determinant for interaction specificity. Results Analysis of Molecular Variance among symbiont ITS sequences across termite hosts at three hierarchical levels showed that 47 % of the variation occurred between genera, 18 % between species, and the remaining 35 % between colonies within species. Different patterns of specificity were evident. High mutual specificity was found for the single Macrotermes species studied, as M. natalensis was associated with a single unique fungal haplotype. The three species of the genus Odontotermes showed low symbiont specificity: they were all associated with a genetically diverse set of fungal symbionts, but their fungal symbionts showed some host specificity, as none of the fungal haplotypes were shared between the studied Odontotermes species. Finally, bilaterally low specificity was found for the four tentatively recognized species of the genus Microtermes, which shared and apparently freely exchanged a common pool of divergent fungal symbionts. Conclusion Interaction specificity was high at the genus level and generally much lower at the species level. A comparison of the observed diversity among fungal symbionts with the diversity among termite hosts, indicated that the fungal symbiont does not follow the general pattern of an endosymbiont, as we found either similar diversity at both sides or higher diversity in the symbiont. Our results further challenge the

  10. Interspecific competition between entomopathogenic nematodes (Steinernema is modified by their bacterial symbionts (Xenorhabdus

    Directory of Open Access Journals (Sweden)

    Pages Sylvie

    2006-09-01

    Full Text Available Abstract Background Symbioses between invertebrates and prokaryotes are biological systems of particular interest in order to study the evolution of mutualism. The symbioses between the entomopathogenic nematodes Steinernema and their bacterial symbiont Xenorhabdus are very tractable model systems. Previous studies demonstrated (i a highly specialized relationship between each strain of nematodes and its naturally associated bacterial strain and (ii that mutualism plays a role in several important life history traits of each partner such as access to insect host resources, dispersal and protection against various biotic and abiotic factors. The goal of the present study was to address the question of the impact of Xenorhabdus symbionts on the progression and outcome of interspecific competition between individuals belonging to different Steinernema species. For this, we monitored experimental interspecific competition between (i two nematode species: S. carpocapsae and S. scapterisci and (ii their respective symbionts: X. nematophila and X. innexi within an experimental insect-host (Galleria mellonella. Three conditions of competition between nematodes were tested: (i infection of insects with aposymbiotic IJs (i.e. without symbiont of both species (ii infection of insects with aposymbiotic IJs of both species in presence of variable proportion of their two Xenorhabdus symbionts and (iii infection of insects with symbiotic IJs (i.e. naturally associated with their symbionts of both species. Results We found that both the progression and the outcome of interspecific competition between entomopathogenic nematodes were influenced by their bacterial symbionts. Thus, the results obtained with aposymbiotic nematodes were totally opposite to those obtained with symbiotic nematodes. Moreover, the experimental introduction of different ratios of Xenorhabdus symbionts in the insect-host during competition between Steinernema modified the proportion of

  11. Superparasitism Drives Heritable Symbiont Epidemiology and Host Sex Ratio in a Wasp.

    Directory of Open Access Journals (Sweden)

    Steven R Parratt

    2016-06-01

    Full Text Available Heritable microbial symbionts have profound impacts upon the biology of their arthropod hosts. Whilst our current understanding of the dynamics of these symbionts is typically cast within a framework of vertical transmission only, horizontal transmission has been observed in a number of cases. For instance, several symbionts can transmit horizontally when their parasitoid hosts share oviposition patches with uninfected conspecifics, a phenomenon called superparasitism. Despite this, horizontal transmission, and the host contact structures that facilitates it, have not been considered in heritable symbiont epidemiology. Here, we tested for the importance of host contact, and resulting horizontal transmission, for the epidemiology of a male-killing heritable symbiont (Arsenophonus nasoniae in parasitoid wasp hosts. We observed that host contact through superparasitism is necessary for this symbiont's spread in populations of its primary host Nasonia vitripennis, such that when superparasitism rates are high, A. nasoniae almost reaches fixation, causes highly female biased population sex ratios and consequently causes local host extinction. We further tested if natural interspecific variation in superparasitism behaviours predicted symbiont dynamics among parasitoid species. We found that A. nasoniae was maintained in laboratory populations of a closely related set of Nasonia species, but declined in other, more distantly related pteromalid hosts. The natural proclivity of a species to superparasitise was the primary factor determining symbiont persistence. Our results thus indicate that host contact behaviour is a key factor for heritable microbe dynamics when horizontal transmission is possible, and that 'reproductive parasite' phenotypes, such as male-killing, may be of secondary importance in the dynamics of such symbiont infections.

  12. Genomic diversification of giant enteric symbionts reflects host dietary lifestyles

    KAUST Repository

    Ngugi, David

    2017-08-24

    Herbivorous surgeonfishes are an ecologically successful group of reef fish that rely on marine algae as their principal food source. Here, we elucidated the significance of giant enteric symbionts colonizing these fishes regarding their roles in the digestive processes of hosts feeding predominantly on polysiphonous red algae and brown Turbinaria algae, which contain different polysaccharide constituents. Using metagenomics, single-cell genomics, and metatranscriptomic analyses, we provide evidence of metabolic diversification of enteric microbiota involved in the degradation of algal biomass in these fishes. The enteric microbiota is also phylogenetically and functionally simple relative to the complex lignocellulose-degrading microbiota of terrestrial herbivores. Over 90% of the enzymes for deconstructing algal polysaccharides emanate from members of a single bacterial lineage,

  13. Caste-specific symbiont policing by workers of Acromyrmex fungus-growing ants

    DEFF Research Database (Denmark)

    Ivens, Aniek B.F.; Nash, David R.; Poulsen, Michael

    2009-01-01

    The interaction between leaf-cutting ants and their fungus garden mutualists is ideal for studying the evolutionary stability of interspecific cooperation. Although the mutualism has a long history of diffuse coevolution, there is ample potential for conflicts between the partners over the mixing...... and transmission of symbionts. Symbiont transmission is vertical by default, and both the ants and resident fungus actively protect the fungal monoculture growing in their nest against secondary introductions of genetically dissimilar symbionts from other colonies. An earlier study showed that mixtures of major...

  14. High Symbiont Relatedness Stabilizes Mutualistic Cooperation in Fungus-Growing Termites

    DEFF Research Database (Denmark)

    Aanen, Duur K; de Fine Licht, Henrik H; Debets, Alfons J M

    2009-01-01

    It is unclear how mutualistic relationships can be stable when partners disperse freely and have the possibility of forming associations with many alternative genotypes. Theory predicts that high symbiont relatedness should resolve this problem, but the mechanisms to enforce this have rarely been...... of spore production in proportion to strain frequency. This positive reinforcement results in an exclusive lifetime association of each host colony with a single fungal symbiont and hinders the evolution of cheating. Our findings explain why vertical symbiont transmission in fungus-growing termites is rare...

  15. Lichen planus remission is associated with a decrease of human herpes virus type 7 protein expression in plasmacytoid dendritic cells

    NARCIS (Netherlands)

    de Vries, Henry J. C.; Teunissen, Marcel B. M.; Zorgdrager, Fokla; Picavet, Daisy; Cornelissen, Marion

    2007-01-01

    The cause of lichen planus is still unknown. Previously we showed human herpes virus 7 (HHV-7) DNA and proteins in lesional lichen planus skin, and significantly less in non-lesional lichen planus, psoriasis or healthy skin. Remarkably, lesional lichen planus skin was infiltrated with plasmacytoid

  16. Lichen Parmelia sulcata time response model to environmental elemental availability

    International Nuclear Information System (INIS)

    Reis, M.A.; Alves, L.C.; Freitas, M.C.; Os, B. van; Wolterbeek, H.Th.

    2000-01-01

    Transplants of lichen Parmelia sulcata collected in an area previously identified as non polluted, were placed at six stations, five of which were near Power Plants and the other in an area expected to be a remote station. Together with the lichen transplants, two total deposition collection buckets and an aerosol sampler were installed. Lichens were recollected two every month from each station. At the same time the water collection buckets were replaced by new ones. The aerosol sampler filter was replaced every week, collection being effective only for 10 minutes out of every two hours; in the remote station aerosol filters were replaced only once a month, the collection rate being kept. Each station was run for a period of one year. Both lichens and aerosol filters were analysed by PIXE and INAA at ITN. Total deposition samples were dried under an infrared lamp, and afterwards acid digested and analysed by ICP-MS at the National Geological Survey of The Netherlands. Data for the three types of samples were then produced for a total of 16 elements. In this work we used the data set thus obtained to test a model for the time response of lichen Parmelia sulcata to a new environment. (author)

  17. Association of classic lichen planus with human herpesvirus-7 infection.

    Science.gov (United States)

    Nahidi, Yalda; Tayyebi Meibodi, Naser; Ghazvini, Kiarash; Esmaily, Habibollah; Esmaeelzadeh, Maryam

    2017-01-01

    Lichen planus is a mucocutaneous papulosquamous itchy disease with unknown etiology. A number of factors such as immune mechanisms, viral agents, and drugs have been implicated in pathogenesis of lichen planus. In recent years, several studies have indicated the role of viral agents in this disease, including human herpesvirus-7 (HHV-7). Studies have given contradictory results, which is why we decided to study the possible association between lichen planus with HHV-7. In this case-control study, which was conducted on 60 cutaneous classic lichen planus samples as well as 60 healthy control skin samples after matching the two groups in terms of gender and age, tissue samples of patients and controls were studied by real time polymerase chain reaction to detect for HHV-7. According to this study, HHV-7 DNA was found in 18 samples of the case group (30.0%) and in six (10.0%) of the control group (P = 0.006). The results of this study support the likely role of HHV-7 in pathogenesis of lichen planus. As an exogenous antigen, this virus may be involved in cellular immune-mediated destruction of keratinocytes. © 2016 The International Society of Dermatology.

  18. Emotional assessment of patients with oral lichen planus.

    Science.gov (United States)

    Alves, Mônica Ghislaine Oliveira; do Carmo Carvalho, Bruna Fernandes; Balducci, Ivan; Cabral, Luiz Antonio Guimarães; Nicodemo, Denise; Almeida, Janete Dias

    2015-01-01

    Oral lichen planus is a chronic immune-mediated disease with an estimated prevalence of 0.5-2.5% in the general population. Patients with oral lichen planus are often emotionally unstable and anxious and may develop concomitant systemic disorders. The objective of this study was to evaluate emotional characteristics of patients with oral lichen planus. Two groups were studied: the first group consisted of 48 patients with a diagnosis of oral lichen planus, and the second group consisted of controls without the disease matched for age and gender at a proportion of 1:1. The emotional state of the patients was evaluated using the State-Trait Anxiety Inventory, SF-36 generic quality of life questionnaire, and the Self Reporting Questionnaire-20. The present investigation demonstrated the presence of anxiety and depression in patients with oral lichen planus and a negative impact of the disorder on the patient's quality of life as indicated by impairment of the physical aspect, vitality, mental health, and social aspect domains. This could indicate that associated psychological treatment may be important in the follow-up of these patients. © 2014 The International Society of Dermatology.

  19. The microbiology of oral lichen planus: Is microbial infection the cause of oral lichen planus?

    Science.gov (United States)

    Baek, K; Choi, Y

    2018-02-01

    Oral lichen planus (OLP) is a variant of lichen planus (LP), a common chronic mucocutaneous inflammatory disease. Cutaneous lesions of LP are self-limiting, but OLP lesions are non-remissive, alternating periods of exacerbation and quiescence, and only symptomatic treatments exist for OLP. The precise etiology and pathogenesis of OLP are hardly understood, which is a major obstacle to the development of new therapeutics for this disease. OLP is considered a T-cell-mediated inflammatory disease. Although various antigens have been considered, what actually triggers the inflammatory response of T cells is unknown. Suggested predisposing factors include genetic factors, stress, trauma, and infection. The aim of this review was to determine whether microbial infection can cause OLP. We first reviewed the association between OLP and microbial factors, including viral, fungal, and bacterial infections. In addition, each microbial factor associated with OLP was assessed by modified guidelines of Fredricks and Relman to determine whether it establishes a causal relationship. In conclusion, no microbial factor yet fulfills the guidelines to establish the causality of OLP. By focusing on the unclarified issues, however, the potential roles of microbial factors in the pathogenesis of OLP will be soon elucidated. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  20. Hyphal walls of isolated lichen fungi

    International Nuclear Information System (INIS)

    Galun, M.; Braun, A.; Frensdorff, A.; Galun, E.

    1976-01-01

    The hyphal walls of three mycobionts, isolated from the lichens Xanthoria parietina, Tornabenia intricata and Sarcogyne sp. were investigated by two techniques: microaudiography of fungal colonies exposed to radioactive carbohydrate precursors; and binding, in vivo, of fluorescein conjugated lectins to hyphal walls of such colonies. N-( 3 H) acetylglucosamine was readily incorporated into tips, young hyphal walls and septa of the three mycobionts and the free-living fungus Trichoderma viride, but not into Phytophthora citrophthora, indicating that chitin is a major component of the mycobionts' hyphal walls. All three mycobionts, but neither of the free-living fungi, incorporated ( 3 H) mannose and ( 3 H) mannitol into their hyphal walls. Fluorescein-conjugated wheat germ agglutinin was bound to the hyphal walls of the three mycobionts and T. viride, but not to the walls of P. citrophthora; the binding pattern was similar to the grain pattern obtained in audiographs after short N-( 3 H) acetylglucosamine labelling. As wheat germ agglutinin binds specifically to chitin oligomers, the lectin binding tests further confirmed that chitin is a mycobiont hyphal wall component. Binding characteristics of several fluorescein-conjugated lectins to the three mycobionts indicated that this technique can yield useful information concerning the chemical composition of hyphal wall surfaces. (orig./AJ) [de

  1. Lichen amyloidosis in an unusual location.

    Science.gov (United States)

    Jhingan, A; Lee, J S S; Kumarasinghe, S P W

    2007-06-01

    We report lichen amyloidosis occurring on the upper lip and nasolabial folds of a 61-year-old woman from Singapore. She had a past history of systemic lupus erythematosus, which was in remission for three years. There had been no lesions of lupus erythematosus in this area. Clinically, the lesions were skin-coloured, firm papules and our differential diagnoses included trichoepithelioma, papular sarcoid or lupus miliaris disseminatus faciei. Skin biopsy from one of the lesions showed amyloid deposits in the dermis which were Congo red stain positive. These deposits also showed apple green birefringence. Immunohistochemical staining of the amyloid deposits stained positive for cytokeratins (CK) 5 and 6, and negative for CK 14. The kappa and lambda stains were equivocal. Further investigations, including multiple myeloma screen and rectal biopsy, ruled out systemic amyloidosis. There was no other evidence of cutaneous amyloidosis on her limbs or trunk. She refused treatment for her lesions. This case highlights the commonly-seen form of primary localised cutaneous amyloidosis in an unusual location.

  2. Eosinophils in lichen sclerosus et atrophicus.

    Science.gov (United States)

    Keith, Phillip J; Wolz, Michael M; Peters, Margot S

    2015-10-01

    The classic histopathologic features of lichen sclerosus et atrophicus (LS) include lymphoplasmacytic inflammation below a zone of dermal edema and sclerosis. The presence of eosinophils in LS has received little attention, but the finding of tissue eosinophils, particularly eosinophilic spongiosis in LS, has been suggested as a marker for the coexistence of autoimmune bullous disease or allergic contact dermatitis (or both). We sought to determine whether the histopathologic presence of dermal eosinophils or eosinophilic spongiosis (or both) in biopsies from patients with LS is associated with autoimmune bullous disease, autoimmune connective tissue disease or allergic contact dermatitis. A retrospective review of the histopathology and medical records of 235 patients with LS who were evaluated from June 1992 to June 2012 was performed. Sixty-nine patients (29%) had eosinophils on histopathology. Among patients with associated diseases, a statistically significant association between the eosinophil cohort and the cohort without eosinophils was not detected. The importance of eosinophils is uncertain, but our data suggest that the finding of tissue eosinophils alone is not sufficient to prompt an extensive workup for additional diagnoses. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  3. Oral lichen planus: focus on etiopathogenesis.

    Science.gov (United States)

    Payeras, Márcia Rodrigues; Cherubini, Karen; Figueiredo, Maria Antonia; Salum, Fernanda Gonçalves

    2013-09-01

    Lichen planus is a chronic mucocutaneous inflammatory disease, which frequently affects the oral mucosa of white females over 40 years old. Its aetiology remains uncertain and the pathogenesis is still the object of much speculation. The present paper presents the most well known antigens, and describes the action of different cells and proteins associated with the development of that disease, as well as the possible agents involved with its malignant transformation. Different external agents, especially virus, and internal agents, like stress, and the heat shock protein antigen expression, associated or not, can alter the basal keratinocytes of the oral mucosa making them susceptible to apoptosis by CD8(+) cytotoxic T cell as well as activate matrix metalloproteinase and mast cell degranulation, which produce a great range of inflammatory mediators and cytokines determining the clinical onset of the disease. Regarding carcinogenesis, since it is a complex process and presents multifactorial origin, it is believed that there may be a synergism between intrinsic, such as inflammation mediators, and extrinsic agents (tobacco, alcohol, viral infections) for the OLP malignant transformation to occur. However, further studies are needed to better understand the origin, pathogenesis and process of malignant transformation of OLP. Copyright © 2013 Elsevier Ltd. All rights reserved.

  4. Alterated integrin expression in lichen planopilaris

    Directory of Open Access Journals (Sweden)

    Erriquez Roberta

    2007-02-01

    Full Text Available Abstract Background Lichen planopilaris (LPP is an inflammatory disease characterized by a lymphomononuclear infiltrate surrounding the isthmus and infundibulum of the hair follicle of the scalp, that evolves into atrophic/scarring alopecia. In the active phase of the disease hairs are easily plucked with anagen-like hair-roots. In this study we focused on the expression of integrins and basement membrane components of the hair follicle in active LPP lesions. Methods Scalp biopsies were taken in 10 patients with LPP and in 5 normal controls. Using monoclonal antibodies against α3β1 and α6β4 integrins we showed the expression of these integrins and of the basement membrane components of the hair follicle in active LPP lesions and in healthy scalp skin. Results In the LPP involved areas, α3β1 was distributed in a pericellular pattern, the α6 subunit was present with a basolateral distribution while the β4 subunit showed discontinuous expression at the basal pole and occasionally, basolateral staining of the hair follicle. Conclusion: An altered distribution of the integrins in active LPP lesions can explain the phenomenon of easy pulling-out of the hair with a "gelatinous" root-sheath.

  5. Antiproliferative, Antibacterial and Antifungal Activity of the Lichen Xanthoria parietina and Its Secondary Metabolite Parietin

    Directory of Open Access Journals (Sweden)

    Adriana Basile

    2015-04-01

    Full Text Available Lichens are valuable natural resources used for centuries throughout the world as medicine, food, fodder, perfume, spices and dyes, as well as for other miscellaneous purposes. This study investigates the antiproliferative, antibacterial and antifungal activity of the acetone extract of the lichen Xanthoria parietina (Linnaeus Theodor Fries and its major secondary metabolite, parietin. The extract and parietin were tested for antimicrobial activity against nine American Type Culture Collection standard and clinically isolated bacterial strains, and three fungal strains. Both showed strong antibacterial activity against all bacterial strains and matched clinical isolates, particularly against Staphylococcus aureus from standard and clinical sources. Among the fungi tested, Rhizoctonia solani was the most sensitive. The antiproliferative effects of the extract and parietin were also investigated in human breast cancer cells. The extract inhibited proliferation and induced apoptosis, both effects being accompanied by modulation of expression of cell cycle regulating genes such as p16, p27, cyclin D1 and cyclin A. It also mediated apoptosis by activating extrinsic and intrinsic cell death pathways, modulating Tumor Necrosis Factor-related apoptosis-inducing ligand (TRAIL and B-cell lymphoma 2 (Bcl-2, and inducing Bcl-2-associated agonist of cell death (BAD phosphorylation. Our results indicate that Xanthoria parietina is a major potential source of antimicrobial and anticancer substances.

  6. Influence of air pollution on epiphytic lichens at Kopmanholm

    Energy Technology Data Exchange (ETDEWEB)

    Moberg, R

    1968-01-01

    Investigations were conducted to determine the effects of pollutants from a sulfate pulp factory at Kopmanholmen, Sweden on epiphytic lichens. In 1965 the factory produced 130,000 tons of pulp, 9000 tons of chlorine, 10,000 tons of alkalies and 4000 tons of sulfuric acid. The air is polluted by sulfur dioxide, organic compounds of sulfur, chlorine, and hydrogen sulfide. Results indicate that no zone is completely lacking lichen vegetation. Alectoria implexa, Cetraria glauca, Parmeliopsis aleurites and P. hyperopta are especially sensitive to air pollution. Alectoria jubata, Cetraria chlorophylla, C. pinastri, Parmelia physodes and Parmeliopsis ambigua, although injured, seem to be less sensitive to air pollution because they were collected close to the factory. The injuries on the lichens are probably not caused by a single component, but the various pollutants interact and probably intensify the effect of each other. Groups of trees in the polluted area reduce the injuries.

  7. Nail lesions as a main manifestation of lichen nitidus

    Directory of Open Access Journals (Sweden)

    Michał Sobjanek

    2015-09-01

    Full Text Available Introduction . Lichen nitidus (LN is a rare, chronic, inflammatory dermatosis usually affecting children and young adults. Nails involvement is very rare. Until now, 7 cases of LN with nail involvement have been described. Objective. To present a rare case of childhood lichen nitidus where trachyonychia was the main manifestation of the disease. Case report. A 7-year-old, Caucasian, previously healthy boy presented thumbnail longitudinal ridges, distal splitting and subungual hyperkeratosis for 7 months. Numerous mycological and bacteriological examinations were negative. Dermatological examination also revealed erythematous lesions on the proximal nail fold as well as small skin-pigmented papules on the thumb. Similar papules grouped into patches were also observed on the upper limbs, trunk and forehead. Treatment was not recommended. Conclusions . Lichen nitidus may rarely affect nails and should be considered as a possible cause of nail lesions in childhood.

  8. Mercury in lichens of Nahuel Huapi National Park, Patagonia, Argentina

    International Nuclear Information System (INIS)

    Ribeiro Guevara, S.; Bubach, D.; Arribere, M.; Nacional de Cuyo Universidad, Bariloche

    2004-01-01

    Mercury and other elements of interest are determined in lichens collected in Nahuel Huapi National Park, Northern Patagonia, Argentina. Pooled samples are analyzed by instrumental neutron activation analysis. Mercury contents in Usnea sp. collected from undisturbed sites range from 0.0558 ± 0.0083 to 1.38 ± 0.18 μg x g -1 . Other potential pollutants are identified by the analysis of Usnea sp. samples, namely Sb, As, Br, Zn, and Se. Previous experiments with foliose and fruticose lichens are also discussed. The analysis of mercury contents of foliose lichens sampled from urban and periurban sites of Bariloche city, and from undisturbed regions, demonstrate that the atmosphere of Bariloche city is enriched in mercury compared to the surroundings. The result is confirmed by transplantation experiments from undisturbed zones to urban sites. (author)

  9. Epiphytic lichens as quantitative biomonitors for atmospheric element deposition

    International Nuclear Information System (INIS)

    Jeran, Z.; Jacimovic, J.; Smodis, B.; Batic, F.

    2000-01-01

    Epiphytic lichens are being used as passive and active biomonitors of trace elements in Slovenia. The lichen Hypogymnia physodes (L.) Nyl. was exposed at three locations (two in the vicinity of a coal fired-power plant, and one at a reference location) for 8 months. At the same locations air particulate matter and total deposition were collected on a monthly basis. The k 0 -method of neutron activation analysis, using the TRIGA Mark II reactor at the 'Jozef Stefan' Institute, was employed for multielemental nondestructive analysis of all samples. The influence of the power plant on the concentration levels of some elements in the transplanted lichens, air particulates and total deposition is discussed and their correlation presented. (author)

  10. Update on oral lichen planus: etiopathogenesis and management

    DEFF Research Database (Denmark)

    Scully, C; Beyli, M; Ferreiro, M C

    1998-01-01

    Lichen planus (LP) is a relatively common disorder of the stratified squamous epithelia, which is, in many ways, an enigma. This paper is the consensus outcome of a workshop held in Switzerland in 1995, involving a selection of clinicians and scientists with an interest in the condition and its...... about the mechanisms involved, and interesting new associations, such as with liver disease, have emerged. The management of lichen planus is still not totally satisfactory, and there is as yet no definitive treatment, but there have been advances in the control of the condition. There is no curative...... management. The oral (OLP) eruptions usually have a distinct clinical morphology and characteristic distribution, but OLP may also present a confusing array of patterns and forms, and other disorders may clinically simulate OLP. Lesions may affect other mucosae and/or skin. Lichen planus is probably...

  11. A characterization NMR of secondary metabolites from lichen Parmotrema praesorediosum

    Science.gov (United States)

    Azman, Anis Asmi; Khalid, Rozida; Bakar, Muntaz Abu

    2018-04-01

    The research study was carried out to extract, isolate and characterize the secondary metabolites of lichen Parmotrema praesorediosum. Most of the lichen samples were obtained from betel nut trees and needle flowers which were collected from 17 different places around UKM Bangi campus. Each lichen sample was dried before being grinded and extracted in methanol for nine days. This process was repeated three times at room temperature. Subsequently, the resulting residues were filtered to obtain the crude extracts and further analysed using Thin Layer Chromatography (TLC) and Vacuum Column Chromatography (VLC). In order to derive the pure compounds, the isolation step was proceeded using Radial Chromatography (RC). These isolated compounds were determined by Nuclear Magnetic Resonances (NMR) and identified as methyl haematomatte (1), methyl chlorohaematomatte (2) and methyl β-orsellinate (3).

  12. MICROMORPHOLOGICAL AND CHEMICAL ASPECTS OF SOME LICHENIZED FUNGI SPECIES

    Directory of Open Access Journals (Sweden)

    PÎNDARU DIANA-MIHAELA

    2012-12-01

    Full Text Available At present, lichenized fungi are used in biomonitoring studies of air quality, being good receptors in the climate change. This paper aims to investigate surface micromorphology of Xanthoria parietina and Phaeophyscia orbicularis species (Lecanoromycetes, Ascomycota. The study also includes the investigation of selected chemical parameters as pH and conductivity of the lichenized fungi samples collected from various locations in the Iaşi County (Romania. Measurements of the pH provide information on the degree of pollution in the location of interest. Bark trees pH was also investigated in order to see if our matrix substrate influences the pH of the interest lichenized fungi samples.

  13. Atmospheric pollutants monitoring by analysis of epiphytic lichens

    International Nuclear Information System (INIS)

    Fuga, Alessandra; Saiki, Mitiko; Marcelli, Marcelo P.; Saldiva, Paulo H.N.

    2008-01-01

    The Canoparmelia texana epiphytic lichenized fungi was used to monitor atmospheric pollution in the Sao Paulo metropolitan region, SP, Brazil. The cluster analysis applied to the element concentration values confirmed the site groups of different levels of pollution due to industrial and vehicular emissions. In the distribution maps of element concentrations, higher concentrations of Ba and Mn were observed in the vicinity of industries and of a petrochemical complex. The highest concentration of Co found in lichens from the Sao Miguel Paulista site is due to the emissions from a metallurgical processing plant that produces this element. For Br and Zn, the highest concentrations could be associated both to vehicular and industrial emissions. Exploratory analyses revealed that the accumulation of toxic elements in C. texana may be of use in evaluating the human risk of cardiopulmonary mortality due to prolonged exposure to ambient levels of air pollution. - Canoparmelia texana lichenized fungi is a valuable biomonitor for atmospheric pollution

  14. The MicroRNA Repertoire of Symbiodinium, the Dinoflagellate Symbiont of Reef-Building Corals

    KAUST Repository

    Baumgarten, Sebastian

    2013-07-01

    Animal and plant genomes produce numerous small RNAs (smRNAs) that regulate gene expression post-transcriptionally affecting metabolism, development, and epigenetic inheritance. In order to characterize the repertoire of endogenous microRNAs and potential gene targets, we conducted smRNA and mRNA expression profiling over nine experimental treatments of cultures from the dinoflagellate Symbiodinium sp. A1, a photosynthetic symbiont of scleractinian corals. We identified a total of 75 novel smRNAs in Symbiodinum sp. A1 that share stringent key features with functional microRNAs from other model organisms. A subset of 38 smRNAs was predicted independently over all nine treatments and their putative gene targets were identified. We found 3,187 animal-like target sites in the 3’UTRs of 12,858 mRNAs and 53 plantlike target sites in 51,917 genes. Furthermore, we identified the core RNAi protein machinery in Symbiodinium. Integration of smRNA and mRNA expression profiling identified a variety of processes that could be under microRNA control, e.g. regulation of translation, DNA modification, and chromatin silencing. Given that Symbiodinium seems to have a paucity of transcription factors and differentially expressed genes, identification and characterization of its smRNA repertoire establishes the possibility of a range of gene regulatory mechanisms in dinoflagellates acting post-transcriptionally.

  15. Investigations on abundance and activity of microbial sponge symbionts using quantitative real - time PCR

    DEFF Research Database (Denmark)

    Kumala, Lars; Hentschel, Ute; Bayer, Kristina

    Marine sponges are hosts to dense and diverse microbial consortia that are likely to play a key role in the metabolic processes of the host sponge due to their enormous abundance. Common symbioses between nitrogen transforming microorganisms and sponges indicate complex nitrogen cycling within...... the host. Of particular interest is determining the community structure and function of microbial symbionts in order to gain deeper insight into host-symbiont interactions. We investigated the abundance and activity of microbial symbionts in two Mediterranean sponge species using quantitative real-time PCR....... An absolute quantification of functional genes and transcripts in archaeal and bacterial symbionts was conducted to determine their involvement in nitrification and denitrification, comparing the low microbial abundance (LMA) sponge Dysidea avara with the high microbial abundance (HMA) representative Aplysina...

  16. Chemosynthetic symbionts of marine invertebrate animals are capable of nitrogen fixation

    NARCIS (Netherlands)

    Petersen, J.M.; Kemper, A.; Gruber-Vodicka, H.R.; Cardini, U.; van der Geest, M.; Kleiner, M.; Bulgheresi, S.; Mußmann, M; Herbold, C.W.; Seah, B.K.B.; Antony, C.P.; Liu, D.; Belitz, A.; Weber, M.

    2016-01-01

    Chemosynthetic symbioses are partnerships between invertebrate animals and chemosynthetic bacteria. The latter are theprimary producers, providing most of the organic carbon needed for the animal host’s nutrition. We sequenced genomesof the chemosynthetic symbionts from the lucinid bivalve Loripes

  17. Mechanisms of symbiont-conferred protection against natural enemies: an ecological and evolutionary framework.

    Science.gov (United States)

    Gerardo, Nicole M; Parker, Benjamin J

    2014-10-01

    Many vertically-transmitted microbial symbionts protect their insect hosts from natural enemies, including host-targeted pathogens and parasites, and those vectored by insects to other hosts. Protection is often achieved through production of inhibiting toxins, which is not surprising given that toxin production mediates competition in many environments. Classical models of macroecological interactions, however, demonstrate that interspecific competition can be less direct, and recent research indicates that symbiont-protection can be mediated through exploitation of limiting resources, and through activation of host immune mechanisms that then suppress natural enemies. Available data, though limited, suggest that effects of symbionts on vectored pathogens and parasites, as compared to those that are host-targeted, are more likely to result from symbiont activation of the host immune system. We discuss these different mechanisms in light of their potential impact on the evolution of host physiological processes. Copyright © 2014 Elsevier Inc. All rights reserved.

  18. Recent expansion of heat-activated retrotransposons in the coral symbiont Symbiodinium microadriaticum

    KAUST Repository

    Chen, Jit Ern; Cui, Guoxin; Wang, Xin; Liew, Yi Jin; Aranda, Manuel

    2017-01-01

    Rising sea surface temperature is the main cause of global coral reef decline. Abnormally high temperatures trigger the breakdown of the symbiotic association between corals and their photosynthetic symbionts in the genus Symbiodinium. Higher

  19. Co-Speciation of Earthworms and their nephridial symbionts, Acidovorax Spp

    DEFF Research Database (Denmark)

    Lund, Marie Braad; Fritz, Michael; Holmstrup, Martin

    2006-01-01

    the extracted DNA. The presence of the symbionts in the ampulla was verified by performing fluorescence in situ hybridization (FISH) on all worm species using an Acidovorax-specific probe. Earthworm and symbiont phylogeny was largely congruent, indicating that host and symbiont have indeed co-evolved since...... the initial bacterial colonization of an ancestral lumbricid worm. However, the association is complicated by the recent discovery of additional, putative symbiotic bacteria which have been detected in the ampulla of several earthworms by FISH. Identity, distribution among earthworms, and function...... within the genus Acidovorax [2], and they are transmitted vertically [3]. For these reasons, we suggest that the earthworm-Acidovorax association has evolved by co-speciation. This hypothesis was tested by a comparative study of earthworm and symbiont phylogeny. Different earthworm species were collected...

  20. Symbiont shuffling linked to differential photochemical dynamics of Symbiodinium in three Caribbean reef corals

    Science.gov (United States)

    Cunning, Ross; Silverstein, Rachel N.; Baker, Andrew C.

    2018-03-01

    Dynamic symbioses with functionally diverse dinoflagellate algae in the genus Symbiodinium may allow some reef corals to alter their phenotypes through `symbiont shuffling', or changes in symbiont community composition. In particular, corals may become more bleaching resistant by increasing the relative abundance of thermally tolerant Symbiodinium in clade D after bleaching. Despite the immediate relevance of this phenomenon to corals living in warming oceans—and to interventions aimed at boosting coral resilience—the mechanisms governing how, why, and when symbiont shuffling occurs are still poorly understood. Here, we performed controlled thermal bleaching and recovery experiments on three species of Caribbean corals hosting mixtures of D1a ( S. trenchii) and other symbionts in clades B or C. We show that the degree of symbiont shuffling is related to (1) the duration of stress exposure and (2) the difference in photochemical efficiency ( F v /F m) of co-occurring symbionts under stress (i.e., the `photochemical advantage' of one symbiont over the other). The advantage of D1a under stress was greatest in Montastraea cavernosa, intermediate in Siderastrea siderea, and lowest in Orbicella faveolata and correlated positively with the magnitude of shuffling toward D1a. In holobionts where D1a had less of an advantage over co-occurring symbionts (i.e., only slightly higher F v /F m under stress), a longer stress duration was required to elicit commensurate increases in D1a abundance. In fact, across these three coral species, 92.9% of variation in the degree of symbiont shuffling could be explained by the time-integrated photochemical advantage of D1a under heat stress. Although F v /F m is governed by numerous factors that this study is unable to resolve mechanistically, its strong empirical relationship with symbiont shuffling helps elucidate general features that govern this process in reef corals, which will help refine predictions of coral responses to

  1. Intrinsic factors of Peltigera lichens influence the structure of the associated soil bacterial microbiota.

    Science.gov (United States)

    Leiva, Diego; Clavero-León, Claudia; Carú, Margarita; Orlando, Julieta

    2016-11-01

    Definition of lichens has evolved from bi(tri)partite associations to multi-species symbioses, where bacteria would play essential roles. Besides, although soil bacterial communities are known to be affected by edaphic factors, when lichens grow upon them these could become less preponderant. We hypothesized that the structure of both the lichen microbiota and the microbiota in the soil underneath lichens is shaped by lichen intrinsic and extrinsic factors. In this work, intrinsic factors corresponded to mycobiont and cyanobiont identities of Peltigera lichens, metabolite diversity and phenoloxidase activity and extrinsic factors involved the site of the forest where lichens grow. Likewise, the genetic and metabolic structure of the lichen and soil bacterial communities were analyzed by fingerprinting. Among the results, metabolite diversity was inversely related to the genetic structure of bacterial communities of lichens and soils, highlighting the far-reaching effect of these substances; while phenoloxidase activity was inversely related to the metabolic structure only of the lichen bacterial microbiota, presuming a more limited effect of the products of these enzymes. Soil bacterial microbiota was different depending on the site and, strikingly, according to the cyanobiont present in the lichen over them, which could indicate an influence of the photobiont metabolism on the availability of soil nutrients. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  2. Live imaging of symbiosis: spatiotemporal infection dynamics of a GFP-labelled Burkholderia symbiont in the bean bug Riptortus pedestris

    Science.gov (United States)

    Kikuchi, Yoshitomo; Fukatsu, Takema

    2014-01-01

    Many insects possess endosymbiotic bacteria inside their body, wherein intimate interactions occur between the partners. While recent technological advancements have deepened our understanding of metabolic and evolutionary features of the symbiont genomes, molecular mechanisms underpinning the intimate interactions remain difficult to approach because the insect symbionts are generally uncultivable. The bean bug Riptortus pedestris is associated with the betaproteobacterial Burkholderia symbiont in a posterior region of the midgut, which develops numerous crypts harbouring the symbiont extracellularly. Distinct from other insect symbiotic systems, R. pedestris acquires the Burkholderia symbiont not by vertical transmission but from the environment every generation. By making use of the cultivability and the genetic tractability of the symbiont, we constructed a transgenic Burkholderia strain labelled with green fluorescent protein (GFP), which enabled detailed observation of spatiotemporal dynamics and the colonization process of the symbiont in freshly prepared specimens. The symbiont live imaging revealed that, at the second instar, colonization of the symbiotic midgut M4 region started around 6 h after inoculation (hai). By 24 hai, the symbiont cells appeared in the main tract and also in several crypts of the M4. By 48 hai, most of the crypts were colonized by the symbiont cells. By 72 hai, all the crypts were filled up with the symbiont cells and the symbiont localization pattern continued during the subsequent nymphal development. Quantitative PCR of the symbiont confirmed the infection dynamics quantitatively. These results highlight the stinkbug-Burkholderia gut symbiosis as an unprecedented model for comprehensive understanding of molecular mechanisms underpinning insect symbiosis. PMID:24103110

  3. Association of spiders and lichen on Robben Island, South Africa: a case report

    Directory of Open Access Journals (Sweden)

    A. Mukherjee

    2010-04-01

    Full Text Available The present study is a firstrecord of spider occurrence on Robben Island, South Africa. Some habitats were rich in lichens. As we know, lichens enhance wildlife habitat in less direct ways. The objective of the study was to examine the potential importance of lichens in enriching spider diversity and abundance. A total of 260 spiders (170 from lichens and 90 from bush were collected following the visual search method over one year. Seasonal trends in overall species richness and abundance indicated that the relative density of spiders was greater in lichens than in bushes. The result suggests that habitat structure, such as branch size and epiphytic lichen abundance, can be an explanation for the greater number of spiders in lichen-rich patches of the island.

  4. Relationships between lichen community composition and concentrations of NO2 and NH3

    International Nuclear Information System (INIS)

    Gadsdon, Sally R.; Dagley, Jeremy R.; Wolseley, Patricia A.; Power, Sally A.

    2010-01-01

    The relationship between different features of lichen communities in Quercus robur canopies and environmental variables, including concentrations of NO 2 and NH 3 was investigated. NO 2 concentration was the most significant variable, it was positively correlated with the proportion of lichen cover comprising nitrophytes and negatively correlated with total lichen cover. None of the lichen community features were correlated with NH 3 concentrations, which were relatively low across the site. Since nitrophytes and nitrophobes are likely to react in opposite directions to nitrogenous compounds, total lichen cover is not a suitable indicator for these pollutants. It is, therefore, suggested that the proportion of lichen cover comprising nitrophytes may be a suitable simple indicator of air quality, particularly in locations where the pollution climate is dominated by oxides of nitrogen. - Response of lichen communities to nitrogenous pollutants.

  5. [The expression and clinical significance of IL-35 in periodontitis and oral lichen planus].

    Science.gov (United States)

    Wang, Yu; Jin, Ying; Wang, Yi-Yue; Xu, Dan-Ni; Lin, Xiao-Ping

    2016-08-01

    To investigate the influence of IL-35 in the pathogenesis of periodontitis and oral lichen planus, and the correlation between periodontitis and oral lichen planus patients. The gingival crevicular fluid(GCF) and serum were collected from patients with oral lichen planus (n=20), periodontitis (n=20), periodontitis and oral lichen planus (n=20) and healthy controls (n=12). The patients' basic information, probing depth, clinical attachment loss, gingival index, sulcus bleeding index were measured and collected. The expression of IL-35 in GCF and serum was detected by ELISA. SPSS19.0 software package was used for statistical analysis. The concentration of IL-35 in patients with periodontitis and oral lichen planus was significantly higher than that of other groups(Poral lichen planus may increase the concentration of IL-35 both in serum and GCF. The expression of IL-35 was positively correlated with periodontitis and oral lichen planus.

  6. The herbaceous landlord: integrating the effects of symbiont consortia within a single host

    Directory of Open Access Journals (Sweden)

    Roo Vandegrift

    2015-11-01

    Full Text Available Plants are typically infected by a consortium of internal fungal associates, including endophytes in their leaves, as well as arbuscular mycorrhizal fungi (AMF and dark septate endophytes (DSE in their roots. It is logical that these organisms will interact with each other and the abiotic environment in addition to their host, but there has been little work to date examining the interactions of multiple symbionts within single plant hosts, or how the relationships among symbionts and their host change across environmental conditions. We examined the grass Agrostis capillaris in the context of a climate manipulation experiment in prairies in the Pacific Northwest, USA. Each plant was tested for presence of foliar endophytes in the genus Epichloë, and we measured percent root length colonized (PRLC by AMF and DSE. We hypothesized that the symbionts in our system would be in competition for host resources, that the outcome of that competition could be driven by the benefit to the host, and that the host plants would be able to allocate carbon to the symbionts in such a way as to maximize fitness benefit within a particular environmental context. We found a correlation between DSE and AMF PRLC across climatic conditions; we also found a fitness cost to increasing DSE colonization, which was negated by presence of Epichloë endophytes. These results suggest that selective pressure on the host is likely to favor host/symbiont relationships that structure the community of symbionts in the most beneficial way possible for the host, not necessarily favoring the individual symbiont that is most beneficial to the host in isolation. These results highlight the need for a more integrative, systems approach to the study of host/symbiont consortia.

  7. New or otherwise interesting lichenized and lichenicolous fungi from Montenegro

    Science.gov (United States)

    Bilovitz, Peter O.; Knežević, Branka; Stešević, Danijela; Vitikainen, Orvo; Dragićević, Snežana; Mayrhofer, Helmut

    2011-01-01

    A list of 256 taxa of lichens (252 species) and 2 species of lichenicolous fungi from Montenegro is presented, including 58 taxa (57 species) new to Montenegro. The list is based on specimens kept in the lichen collections of the herbaria GZU, H, Podgorica, and in the private herbarium of Klaus Kalb, and on recent field work in various parts of the country. The genera Biatoridium, Carbonea, Cercidospora, Heppia, Hyperphyscia, Hypocenomyce, Leprocaulon, Lethariella, Megalospora, Orphniospora, Psorinia and Vahliella are reported from Montenegro for the first time. PMID:22102779

  8. Detection of herbaceous-plant pararetrovirus in lichen herbarium samples.

    Science.gov (United States)

    Petrzik, K; Koloniuk, I; Sarkisová, T; Číhal, L

    2016-06-01

    Cauliflower mosaic virus (CaMV) - a plant pararetrovirus that naturally causes diseases in Brassicaceae and Solanaceae plant hosts worldwide - has been detected by PCR for the first time in herbarium samples of Usnea sp. lichens. The virus's presence in these lichens did not result in any micro- or macromorphological changes, and the herbarium records were classified as representative for the distinct species. Sequence analyses classified all the detected viruses into one lineage of CaMV isolates. We have shown here that herbarium samples could be a good source for virus study, especially where a longer time span is involved.

  9. Epiphytic lichens as indicators of air pollution by sulfur dioxide

    Energy Technology Data Exchange (ETDEWEB)

    Goodman, G; Rose, F

    1973-01-01

    Epiphytic lichens show specific differential responses to sulfur dioxide in the air, and it has been possible to construct a scale of SO/sub 2/ pollution based upon lichen communities present upon trees. Maps of pollution zones have now been prepared for England, Wales and Northern France. It has proved possible to correlate these zones with mean winter levels of sulfur dioxide measured instrumentally. Laboratory studies indicate the essential validity of this approach. An interesting correlation between air pollution and topography can be demonstrated in much of south-east England.

  10. Analytical and statistical analysis of elemental composition of lichens

    International Nuclear Information System (INIS)

    Calvelo, S.; Baccala, N.; Bubach, D.; Arribere, M.A.; Riberio Guevara, S.

    1997-01-01

    The elemental composition of lichens from remote southern South America regions has been studied with analytical and statistical techniques to determine if the values obtained reflect species, growth forms or habitat characteristics. The enrichment factors are calculated discriminated by species and collection site and compared with data available in the literature. The elemental concentrations are standardized and compared for different species. The information was statistically processed, a cluster analysis was performed using the three first principal axes of the PCA; the three groups formed are presented. Their relationship with the species, collection sites and the lichen growth forms are interpreted. (author)

  11. Hepatitis B virus in Nigerians with Lichen planus | Daramola | West ...

    African Journals Online (AJOL)

    La fréquence des cas de HBV chez les Nigerians atteints du lichen planus ne sont pas encore documentés dans la littérature en depit de la fréquence élevée de HBV dans la région et des rapports d'un rapport éventue entre le lichen planus et HBV dans ce centre et dans d'autre régions. L'objet de cette étude était de ...

  12. Lichens of the Mahabaleshwar Panchgani Ecosensitive zone (MPESZ, Maharashtra, India

    Directory of Open Access Journals (Sweden)

    G.S. Pandit

    2014-05-01

    Full Text Available Mahabaleshwar Panchgani Ecosensitive Zone located in the Northern Western Ghats of India is well known for its rich biodiversity. Rocky plateaus of laterite are a prominent feature of this region along with a mosaic landscape of forest and shrub-savannah vegetation. A checklist of 129 lichen species reported from this region has been compiled based upon primary and secondary data. They are categorized as per forms and substrates. The need for further studies and protection of this rich lichen diversity is emphasized.

  13. FIELD CANCERIZATION IN LICHEN PLANUS – AN UNUSUAL CASE REPORT

    Directory of Open Access Journals (Sweden)

    Tamgadge Avinash

    2012-12-01

    Full Text Available Lichen Planus is a muco-cutaneous disorder affecting females. The oral lesions precede the skin lesions, with malignant potential rate, ranging from 0.3 to 3%. Malignant changes are usually associated with stress and cocarcinogens. Usually, malignant transformation is presented as solitary lesion in the oral cavity, Oral Squamous Cell Carcinoma (OSCC, developing at multiple sites, as a very rare finding in patients of Oral Lichen Planus (OLP. A case of OLP without risk factors and strong history of stress, the Grinspan syndrome with field cancerization is presented in this article

  14. High acidity tolerance in lichens with fumarprotocetraric, perlatolic or thamnolic acids is correlated with low pKa1 values of these lichen substances

    International Nuclear Information System (INIS)

    Hauck, Markus; Juergens, Sascha-Rene; Huneck, Siegfried; Leuschner, Christoph

    2009-01-01

    The depsidone fumarprotocetraric acid as well as the depsides perlatolic and thamnolic acids are lichen secondary metabolites. Their first dissociation constants (pK a1 ) in methanol were determined to be 2.7 for perlatolic acid and 2.8 for fumarprotocetraric and thamnolic acids by UV spectroscopy. Lower pK a1 values are, so far, not known from lichen substances. Several lichens producing at least one of these compounds are known for their outstanding tolerance to acidic air pollution. This is demonstrated by evaluating published pH preferences for central European lichens. The low pK a1 values suggest that strong dissociation of the studied lichen substances is a prerequisite for the occurrence of lichens with these compounds on very acidic substrata, as protonated lichen substances of different chemical groups, but not their conjugated bases, are known to shuttle protons into the cytoplasm and thereby apparently damage lichens. - Depsides and depsidones with low pK a1 values occur in highly acidity-tolerant lichens.

  15. High acidity tolerance in lichens with fumarprotocetraric, perlatolic or thamnolic acids is correlated with low pK{sub a1} values of these lichen substances

    Energy Technology Data Exchange (ETDEWEB)

    Hauck, Markus, E-mail: mhauck@gwdg.d [Albrecht von Haller Institute of Plant Sciences, Dept. Plant Ecology, University of Goettingen, Untere Karspuele 2, D-37073 Goettingen (Germany); Juergens, Sascha-Rene [Albrecht von Haller Institute of Plant Sciences, Dept. Plant Ecology, University of Goettingen, Untere Karspuele 2, D-37073 Goettingen (Germany); Huneck, Siegfried [Fliederweg 34a, D-06179 Langenbogen, Saalkreis (Germany); Leuschner, Christoph [Albrecht von Haller Institute of Plant Sciences, Dept. Plant Ecology, University of Goettingen, Untere Karspuele 2, D-37073 Goettingen (Germany)

    2009-10-15

    The depsidone fumarprotocetraric acid as well as the depsides perlatolic and thamnolic acids are lichen secondary metabolites. Their first dissociation constants (pK{sub a1}) in methanol were determined to be 2.7 for perlatolic acid and 2.8 for fumarprotocetraric and thamnolic acids by UV spectroscopy. Lower pK{sub a1} values are, so far, not known from lichen substances. Several lichens producing at least one of these compounds are known for their outstanding tolerance to acidic air pollution. This is demonstrated by evaluating published pH preferences for central European lichens. The low pK{sub a1} values suggest that strong dissociation of the studied lichen substances is a prerequisite for the occurrence of lichens with these compounds on very acidic substrata, as protonated lichen substances of different chemical groups, but not their conjugated bases, are known to shuttle protons into the cytoplasm and thereby apparently damage lichens. - Depsides and depsidones with low pK{sub a1} values occur in highly acidity-tolerant lichens.

  16. Complete life cycle of the lichen fungus Calopadia puiggarii (Pilocarpaceae, Ascomycetes) documented in situ: propagule dispersal, establishment of symbiosis, thallus development, and formation of sexual and asexual reproductive structures.

    Science.gov (United States)

    Sanders, William B

    2014-11-01

    The life histories of lichen fungi are not well known and cannot be readily studied in laboratory culture. This work documents in situ the complete life cycle of the widespread crustose lichen Calopadia puiggarii, which reproduces sexually and asexually on the surfaces of leaves. Plastic cover slips held in a mesh frame were placed over leaves in the field and successively removed for microphotography of colonizing lichens. Macroconidia produced within campylidia encircled photobiont cells and codispersed with them, a feature not reported previously for C. puiggarii. Dispersed macroconidia readily germinated and lichenized the photobionts. Algal cells were often dislodged from the encircling macroconidia, providing a likely source for the free-living populations observed. Aposymbiotically dispersed ascospores germinated and lichenized nearby algal cells soon after dispersal. Thallus areolae merged readily in early development, although adjacent mature thalli were often separated by growth inhibition zones. Pycnidia are reported for the first time in Calopadia; their pyriform microconidia probably function as male gametes (spermatia). Pycnidia, apothecia, and campylidia began development similarly as darkly pigmented primordia on the fungal prothallus. Abundant dispersal of ascospores, conidia, and photobionts allows C. puiggarii to quickly colonize leaves with the dual advantages of sexual and asexual reproduction, and with the added convenience of having its algal partner on hand. Fusions and prothallic capture of additional algae provide many opportunities for multiple mycobiont and photobiont genotypes to be combined in a single thallus, but the outcomes of such events remain to be explored. © 2014 Botanical Society of America, Inc.

  17. Lichen Planus Pigmentosus: The Controversial Consensus

    Science.gov (United States)

    Ghosh, Aparajita; Coondoo, Arijit

    2016-01-01

    A pigmented variant of lichen planus (LP) was first reported from India in 1974 by Bhutani et al. who coined the term LP pigmentosus (LPP) to give a descriptive nomenclature to it. LP has a number of variants, one of which is LPP. This disease has also later been reported from the Middle East, Latin America, Korea, and Japan, especially in people with darker skin. It has an insidious onset. Initially, small, black or brown macules appear on sun-exposed areas. They later merge to form large hyperpigmented patches. The disease principally affects the sun-exposed areas of the body such as the face, trunk, and upper extremities. The oral mucosa may rarely be involved. However, the palms, soles, and nails are not affected. Histologically, the epidermis is atrophic along with vacuolar degeneration of basal cell layer. The dermis exhibits incontinence of pigment with scattered melanophages and a sparse follicular or perivascular infiltrate. There is a considerable similarity in histopathological findings between LPP and erythema dyschromicum perstans. However, there are immunologic and clinical differences between the two. These observations have led to a controversy regarding the identity of the two entities. While some dermatologists consider them to be the same, others have opined that the two should be considered as distinctly different diseases. A number of associations such as hepatitis C virus infection, frontal fibrosing alopecia, acrokeratosis of Bazex and nephrotic syndrome have been reported with LPP. A rare variant, LPP inversus, with similar clinical and histopathological findings was reported in 2001. As opposed to LPP, this variant occurs in covered intertriginous locations such as groins and axillae and mostly affects white-skinned persons. PMID:27688435

  18. cultural

    Directory of Open Access Journals (Sweden)

    Irene Kreutz

    2006-01-01

    Full Text Available Es un estudio cualitativo que adoptó como referencial teorico-motodológico la antropología y la etnografía. Presenta las experiencias vivenciadas por mujeres de una comunidad en el proceso salud-enfermedad, con el objetivo de comprender los determinantes sócio-culturales e históricos de las prácticas de prevención y tratamiento adoptados por el grupo cultural por medio de la entrevista semi-estructurada. Los temas que emergieron fueron: la relación entre la alimentación y lo proceso salud-enfermedad, las relaciones con el sistema de salud oficial y el proceso salud-enfermedad y lo sobrenatural. Los dados revelaron que los moradores de la comunidad investigada tienen un modo particular de explicar sus procedimientos terapéuticos. Consideramos que es papel de los profesionales de la salud en sus prácticas, la adopción de abordajes o enfoques que consideren al individuo en su dimensión sócio-cultural e histórica, considerando la enorme diversidad cultural en nuestro país.

  19. Acquisition of a Novel Sulfur-Oxidizing Symbiont in the Gutless Marine Worm Inanidrilus exumae

    Science.gov (United States)

    2018-01-01

    ABSTRACT Gutless phallodrilines are marine annelid worms without a mouth or gut, which live in an obligate association with multiple bacterial endosymbionts that supply them with nutrition. In this study, we discovered an unusual symbiont community in the gutless phallodriline Inanidrilus exumae that differs markedly from the microbiomes of all 22 of the other host species examined. Comparative 16S rRNA gene sequence analysis and fluorescence in situ hybridization revealed that I. exumae harbors cooccurring gamma-, alpha-, and deltaproteobacterial symbionts, while all other known host species harbor gamma- and either alpha- or deltaproteobacterial symbionts. Surprisingly, the primary chemoautotrophic sulfur oxidizer “Candidatus Thiosymbion” that occurs in all other gutless phallodriline hosts does not appear to be present in I. exumae. Instead, I. exumae harbors a bacterial endosymbiont that resembles “Ca. Thiosymbion” morphologically and metabolically but originates from a novel lineage within the class Gammaproteobacteria. This endosymbiont, named Gamma 4 symbiont here, had a 16S rRNA gene sequence that differed by at least 7% from those of other free-living and symbiotic bacteria and by 10% from that of “Ca. Thiosymbion.” Sulfur globules in the Gamma 4 symbiont cells, as well as the presence of genes characteristic for autotrophy (cbbL) and sulfur oxidation (aprA), indicate that this symbiont is a chemoautotrophic sulfur oxidizer. Our results suggest that a novel lineage of free-living bacteria was able to establish a stable and specific association with I. exumae and appears to have displaced the “Ca. Thiosymbion” symbionts originally associated with these hosts. IMPORTANCE All 22 gutless marine phallodriline species examined to date live in a highly specific association with endosymbiotic, chemoautotrophic sulfur oxidizers called “Ca. Thiosymbion.” These symbionts evolved from a single common ancestor and represent the ancestral trait for

  20. Co-infection and localization of secondary symbionts in two whitefly species

    Science.gov (United States)

    2010-01-01

    Background Whiteflies are cosmopolitan phloem-feeding pests that cause serious damage to many crops worldwide due to direct feeding and vectoring of many plant viruses. The sweetpotato whitefly Bemisia tabaci (Gennadius) and the greenhouse whitefly Trialeurodes vaporariorum (Westwood) are two of the most widespread and damaging whitefly species. To complete their unbalanced diet, whiteflies harbor the obligatory bacterium Portiera aleyrodidarum. B. tabaci further harbors a diverse array of secondary symbionts, including Hamiltonella, Arsenophonus, Cardinium, Wolbachia, Rickettsia and Fritschea. T. vaporariorum is only known to harbor P. aleyrodidarum and Arsenophonus. We conducted a study to survey the distribution of whitefly species in Croatia, their infection status by secondary symbionts, and the spatial distribution of these symbionts in the developmental stages of the two whitefly species. Results T. vaporariorum was found to be the predominant whitefly species across Croatia, while only the Q biotype of B. tabaci was found across the coastal part of the country. Arsenophonus and Hamiltonella were detected in collected T. vaporariorum populations, however, not all populations harbored both symbionts, and both symbionts showed 100% infection rate in some of the populations. Only the Q biotype of B. tabaci was found in the populations tested and they harbored Hamiltonella, Rickettsia, Wolbachia and Cardinium, while Arsenophonus and Fritschea were not detected in any B. tabaci populations. None of the detected symbionts appeared in all populations tested, and multiple infections were detected in some of the populations. All endosymbionts tested were localized inside the bacteriocyte in both species, but only Rickettsia and Cardinium in B. tabaci showed additional localization outside the bacteriocyte. Conclusions Our study revealed unique co-infection patterns by secondary symbionts in B. tabaci and T. vaporariorum. Co-sharing of the bacteriocyte by the primary

  1. Identification of a common cyanobacterial symbiont associated with Azolla spp. through molecular and morphological characterization of free-living and symbiotic cyanobacteria.

    Science.gov (United States)

    Gebhardt, J S; Nierzwicki-Bauer, S A

    1991-01-01

    Symbiotically associated cyanobacteria from Azolla mexicana and Azolla pinnata were isolated and cultured in a free-living state. Morphological analyses revealed differences between the free-living isolates and their symbiotic counterparts, as did restriction fragment length polymorphism (RFLP) analyses with both single-copy glnA and rbcS gene probes and a multicopy psbA gene probe. RFLP analyses with Anabaena sp. strain PCC 7120 nifD excision element probes, including an xisA gene probe, detected homologous sequences in DNA extracted from the free-living isolates. Sequences homologous to these probes were not detected in DNA from the symbiotically associated cyanobacteria. These analyses indicated that the isolates were not identical to the major cyanobacterial symbiont species residing in leaf cavities of Azolla spp. Nevertheless, striking similarities between several free-living isolates were observed. In every instance, the isolate from A. pinnata displayed banding patterns virtually identical to those of free-living cultures previously isolated from Azolla caroliniana and Azolla filiculoides. These results suggest the ubiquitous presence of a culturable minor cyanobacterial symbiont in at least three species of Azolla. Images PMID:1685078

  2. The lichens of Marion and Prince Edward Islands

    NARCIS (Netherlands)

    Øvstedal, D.O.; Gremmen, N.J.M.

    2001-01-01

    A total of 100 lichen species are listed for the islands. Six species are described as new to science: Arctomia subantarctica Øvstedal, Arthothelium evanescens Øvstedal, Coccotrema stellata Øvstedal, Ramonia subantarctica Øvstedal, Thelocarpon subantarcticum Øvstedal and Verrucaria umbilicata

  3. Lichens as litmus for air pollution: a historical review

    Energy Technology Data Exchange (ETDEWEB)

    Hawksworth, D L

    1971-01-01

    The literature on the relationships between lichens and air pollution is reviewed, with particular reference to the development of the concepts governing their use as indicators of air pollution levels. Lichens are particularly sensitive to sulfur dioxide which acts by the destruction of chlorophyll. By considering both the species present and their abundance, zones indicative of mean air pollution levels can be quickly mapped. The way in which some species respond in different regions varies and so zonal scales can only be reliably applied in the areas where they were devised. Only in a few cases has it been possible to correlate lichen zones with particular sulfur dioxide concentrations, principally because of a lack of physico-chemical measurements; but even where such correlations are not possible, lichen zones provide a rapid qualitative means of assessing the effects of air pollution. Maps showing the type of data obtained by this method are presented, and a table summarizes the published work on major cities, towns, industrial plants, and in larger geographical regions. 119 references, 5 figures, 3 tables.

  4. Revision of the lichens of the Netherlands. I. Parmeliaceae

    NARCIS (Netherlands)

    Maas Geesteranus, R.A.

    1947-01-01

    It was shown that the oldest Dutch lichen herbarium known was that of H. Boerhaave dating as far back as the end of the 17th or the beginning of the 18th century. After that there was a long spell of inactivity, until from about 1835 onward the florists again started making herbaria. From the end of

  5. Np-237 in peat and lichen in Finland

    DEFF Research Database (Denmark)

    Salminen, S.; Paatero, J.; Roos, Per

    2009-01-01

    Activity concentrations of 237Np in peat and lichen samples in Finland were determined and contributions from nuclear weapons testing in 1950–1960s and the Chernobyl accident were estimated. 237Np was determined with ICP-MS using 235Np as a tracer. Activity concentrations of 237Np in peat samples...

  6. Diversity and ecology of lichens on churches in The Netherlands

    NARCIS (Netherlands)

    Sparrius, L.B.; Aptroot, A.; van Herk, C.M.

    2007-01-01

    This study presents the results of an inventory of lichen species on the walls of 344 medieval and renaissance churches in the Netherlands. In total, 194 species were recorded, of which several are more or less confined to this habitat in the country. We found several regional differences in species

  7. A first note on foliicolous lichens of Assam, India

    Directory of Open Access Journals (Sweden)

    Pooja Gupta

    2016-07-01

    Full Text Available A first note on foliicolous lichens of Assam enumerating 26 species belonging to 15 genera and eight families are provided.  Four species viz., Bacidina apiahica, Byssoloma chlorinum, Calopadia fusca and Strigula nitidula are reported for the first time from Assam.  A number of rare species are present, including Aulaxina uniseptata, Calenia aspidota and Psorotheciopsis patellarioides. 

  8. utilisation des lichens comme bioindicateurs de la pollution

    African Journals Online (AJOL)

    hydro

    le plomb, cadmium et zinc de la région de Rabat-Sale-Zemmour-Zaêr ... Use of lichens as bioindicators of air pollution by lead, cadmium and zinc in the ...... World-Wide Intercomparison exercice for the determination of trace elements and in.

  9. Lichen Sclerosus Atrophicus [LSA] in the Areolae: A Case Report

    Directory of Open Access Journals (Sweden)

    L. Padmavathy

    2012-01-01

    Full Text Available Lichen sclerosus (LS is a chronic inflammatory disorder of an unknown aetiology most commonly affecting the anogenital area. However, extragenital involvement also occurs uncommonly. A case of extra-genital LS involving the areolae of both breasts, in a 15-year-old boy, is reported for its rarity.

  10. Hepatitis C virus infection in patients with oral lichen planus ...

    African Journals Online (AJOL)

    Background: Lichen planus (LP) is a chronic mucocutaneous disease of uncertain etiology. Recent reports suggest that LP is an extrahepatic manifestation of Hepatitis C infection. Objective: To determine the association of Hepatitis C virus (HCV) infection with oral LP and to study the tests of liver function in patients with ...

  11. Childhood lichen sclerosus is a rare but important diagnosis

    DEFF Research Database (Denmark)

    Jensen, Lise Soldbro; Bygum, Anette

    2012-01-01

    Lichen sclerosus (LS) is a chronic skin disorder with a predilection for the anogenital area. The disease is mostly seen in prepubertal and postmenopausal females. The lesions present as sharply demarcated white plaques encircling the vagina and anus. The atrophic form can lead to scarring...

  12. Effects of ammonia from livestock farming on lichen photosynthesis

    Energy Technology Data Exchange (ETDEWEB)

    Paoli, Luca [Department of Environmental Science ' G. Sarfatti' , University of Siena, via Mattioli 4, I-53100 Siena (Italy); Department of Biology, University of Crete, 71409 Heraklion, Crete (Greece); Pirintsos, Stergios Arg.; Kotzabasis, Kiriakos [Department of Biology, University of Crete, 71409 Heraklion, Crete (Greece); Pisani, Tommaso [Department of Environmental Science ' G. Sarfatti' , University of Siena, via Mattioli 4, I-53100 Siena (Italy); Navakoudis, Eleni [Department of Biology, University of Crete, 71409 Heraklion, Crete (Greece); Loppi, Stefano, E-mail: loppi@unisi.i [Department of Environmental Science ' G. Sarfatti' , University of Siena, via Mattioli 4, I-53100 Siena (Italy)

    2010-06-15

    This study investigated if atmospheric ammonia (NH{sub 3}) pollution around a sheep farm influences the photosynthetic performance of the lichens Evernia prunastri and Pseudevernia furfuracea. Thalli of both species were transplanted for up to 30 days in a semi-arid region (Crete, Greece), at sites with concentrations of atmospheric ammonia of ca. 60 mug/m{sup 3} (at a sheep farm), ca. 15 mug/m{sup 3} (60 m from the sheep farm) and ca. 2 mug/m{sup 3} (a remote area 5 km away). Lichen photosynthesis was analysed by the chlorophyll a fluorescence emission to identify targets of ammonia pollution. The results indicated that the photosystem II of the two lichens exposed to NH{sub 3} is susceptible to this pollutant in the gas-phase. The parameter PI{sub ABS}, a global index of photosynthetic performance that combines in a single expression the three functional steps of the photosynthetic activity (light absorption, excitation energy trapping, and conversion of excitation energy to electron transport) was much more sensitive to NH{sub 3} than the F{sub V}/F{sub M} ratio, one of the most commonly used stress indicators. - Ammonia from livestock farming affects lichen photosynthesis.

  13. The lichen and bryophyte vegetation of Cuverville Island, Antarctica

    NARCIS (Netherlands)

    de Leeuw, C; Aptroot, A; van Zanten, B

    1998-01-01

    In the Antarctic summer of 1993 the vegetation of Cuverville Island, a small island near the west coast of the Antarctic Peninsula, was mapped and described. Eleven different plant communities of algae, lichens, bryophytes and spermatophytes have been distinguished. The 51 species Vary from endemic

  14. Lichen Secondary Metabolite, Physciosporin, Inhibits Lung Cancer Cell Motility

    Science.gov (United States)

    Yang, Yi; Park, So-Yeon; Nguyen, Thanh Thi; Yu, Young Hyun; Nguyen, Tru Van; Sun, Eun Gene; Udeni, Jayalal; Jeong, Min-Hye; Pereira, Iris; Moon, Cheol; Ha, Hyung-Ho; Kim, Kyung Keun; Hur, Jae-Seoun; Kim, Hangun

    2015-01-01

    Lichens produce various unique chemicals that can be used for pharmaceutical purposes. To screen for novel lichen secondary metabolites showing inhibitory activity against lung cancer cell motility, we tested acetone extracts of 13 lichen samples collected in Chile. Physciosporin, isolated from Pseudocyphellaria coriacea (Hook f. & Taylor) D.J. Galloway & P. James, was identified as an effective compound and showed significant inhibitory activity in migration and invasion assays against human lung cancer cells. Physciosporin treatment reduced both protein and mRNA levels of N-cadherin with concomitant decreases in the levels of epithelial-mesenchymal transition markers such as snail and twist. Physciosporin also suppressed KITENIN (KAI1 C-terminal interacting tetraspanin)-mediated AP-1 activity in both the absence and presence of epidermal growth factor stimulation. Quantitative real-time PCR analysis showed that the expression of the metastasis suppressor gene, KAI1, was increased while that of the metastasis enhancer gene, KITENIN, was dramatically decreased by physciosporin. Particularly, the activity of 3’-untranslated region of KITENIN was decreased by physciosporin. Moreover, Cdc42 and Rac1 activities were decreased by physciosporin. These results demonstrated that the lichen secondary metabolite, physciosporin, inhibits lung cancer cell motility through novel mechanisms of action. PMID:26371759

  15. Additions to the lichen diversity of Macedonia (FYROM)

    Czech Academy of Sciences Publication Activity Database

    Malíček, Jiří; Mayrhofer, H.

    2017-01-01

    Roč. 30, č. 2 (2017), s. 431-444 ISSN 0018-0971 Institutional support: RVO:67985939 Keywords : Balkan Peninsula * lichen ised fungi * Immersaria Subject RIV: EF - Botanics OBOR OECD: Plant sciences, botany Impact factor: 0.740, year: 2016

  16. Diversity in a Hidden Community: Tardiagrades in Lichens.

    Science.gov (United States)

    Shofner, Marcia; Vodopich, Darrell

    1993-01-01

    Describes an interesting field experiment examining the distribution and diversity of a single community using lichens and the animals living in them. Combining field experience and laboratory work reveals not only the biology of some unusual organisms, but also community ecology and diversity. (PR)

  17. Rinodina degeliana: a corticolous lichen species overlooked in Poland

    Directory of Open Access Journals (Sweden)

    Dariusz Kubiak

    2013-12-01

    Full Text Available New localities of Rinodina degeliana in Poland are described. The morphology, chemistry, distribution and ecology of the species are discussed and characters that help to differentiate R. degaliana from similar lichens are presented. The species is relatively frequent in lime-hornbeam forests of northern and central Poland.

  18. Biomonitoring of heavy metals using Usnea antarctica lichens (extended abstract)

    Czech Academy of Sciences Publication Activity Database

    Zvěřina, O.; Coufalík, Pavel; Barták, M.; Komárek, J.

    2016-01-01

    Roč. 6, č. 2 (2016), s. 238-239 ISSN 1805-0689. [Biosciences in Polar and Alpine Research. Workshop 2016. Brno, 23.11.2016-23.11.2016] Institutional support: RVO:68081715 Keywords : heavy metal * lichen * Antarctica Subject RIV: CB - Analytical Chemistry, Separation OBOR OECD: Analytical chemistry

  19. ANTHRAQUINONE FROM THALLUS OF LICHEN Ramalina javanica Nyl

    Directory of Open Access Journals (Sweden)

    Suyanto Suyanto

    2010-06-01

    Full Text Available The isolation of 1,3,8- trihydroxy-2(1'-pentanol-6-methoxy anthraquinone from acetone extract of lichen thallus of Ramalina javanica Nyl. was carried out. Its structure was determined based on spectroscopic evidences.   Keywords: Ramalina javanica Nyl., anthraquinone

  20. Lichen sclerosus er en forsømt sygdom

    DEFF Research Database (Denmark)

    Sander, Bente Braad; Damsgaard, Knud

    2011-01-01

    We present a small review of lichen sclerosus in women and an update on the newest knowledge, e.g. on calcineurin inhibitors as a choice of treatment. The goal is to put more focus on the disease in Denmark because it is so often diagnosed only with a great delay. We further emphasize...

  1. Do lichens have "memory" of their native nitrogen environment?

    Science.gov (United States)

    Munzi, Silvana; Loppi, Stefano; Cruz, Cristina; Branquinho, Cristina

    2011-02-01

    This study aimed to deepen the knowledge about intraspecific mechanisms regulating nitrogen tolerance in lichens to wet nitrogen deposition. Thalli of the nitrophilous lichen Xanthoria parietina were collected from environments with different nitrogen availabilities and immersed in 80 mL of ammonium sulphate (NH₄)₂SO₄ solutions with distinct concentrations (0, 0.025, 0.05 and 0.25 M) for 5 h per day during 3 days in a week. After each soaking event, lichens were air dried. After each treatment, maximal PSII efficiency, localization of ammonium ions, concentrations of K+ and Mg²+ and thalli buffer capacity were determined. Our results show that lichens are marked by their native nitrogen environment, since there were important differences between the physiological responses of X. parietina thalli previously grown in an area with high nitrogen deposition (nitrogen emissions of ca. 13,000 t/year) and those previously grown in an unpolluted area (nitrogen emissions of ca. 500 t/year). Greater N availability seems to enable X. parietina to cope better with the effects of nitrogen pollution.

  2. Severe recurrent oral ulceration secondary to erosive lichen planus

    International Nuclear Information System (INIS)

    Nadeem, A.; Khan, S.; Satti, A.A.

    2008-01-01

    A case of recurrent progressively severe ulceration secondary to erosive lichen planus is reported. The patient developed marked malnutrition as a result of extensive involvement of the oral cavity. In addition to the oral ulcerations, she also had violaceous spots present over her forearm. Treatment administered in view of histopathological report and clinical presentation, resulted in marked improvement in symptoms and weight gain. (author)

  3. CO2 laser evaporation of oral lichen planus

    NARCIS (Netherlands)

    van der Hem, P. S.; Egges, M.; van der Wal, J. E.; Roodenburg, J. L. N.

    Oral lichen planus is a relatively common disease of the oral mucosa. The buccal mucosa and lateral border of the tongue are mostly involved, although the condition can occur anywhere in the oral cavity. The erosive type in particular can cause spontaneous pain during eating. In the period from 1975

  4. Comparison of topical tretinoin and betamethasone in oral lichen planus

    Directory of Open Access Journals (Sweden)

    Kar H

    1996-01-01

    Full Text Available Thirty-one patients of oral lichen planus were enrolled in this study and two groups were made. Group 1 consisting of 16 patients who applied topical tretinoin 0.05% and Group 2 comprising of 15 patients who were given topical betamethasone dipropionate 0.05%. The patients applying tretinoin showed statistically significant improvement as compared to patients applying betamethasone.

  5. Disease scoring systems for oral lichen planus; a critical appraisal

    NARCIS (Netherlands)

    Wang, J.; van der Waal, I.

    2015-01-01

    The aim of the present study has been to critically review 22 disease scoring systems (DSSs) on oral lichen planus (OLP) that have been reported in the literature during the past decades. Although the presently available DSSs may all have some merit, particularly for research purposes, the diversity

  6. Air pollution and urban climate in the Rhine--Westphalian industrial area and their influence on lichen growth on trees

    Energy Technology Data Exchange (ETDEWEB)

    Domroes, M

    1966-01-01

    Lichens on tree boles were examined on 25,114 trees along streets and areas in the central part of the Ruhr District and related to air pollution concentrations. The lichens were studied with regard to physiognomy, density, and exposition, and in relation to bark characteristics of tree species. Lichens were classified into the following areas: Lichen desert, transitional zone, or area of normal distribution. The lichens were sensitive to air pollution, especially sulfur dioxide emissions. The damaging influence of the town climate, especially aridity, was taken into consideration. Lichens were missing in all areas with a high degree of air pollution. These were areas of high density housing and of lower humidity than open country. Areas which had lower housing density and lower humidity also had increased lichen damage. Lichens were missing in the immediate neighborhood of factories or industrial areas outside towns. Lichen growth was reduced along busy roads.

  7. Bioaccumulation behaviour of transplants of the lichen Flavoparmelia caperata in relation to total deposition at a polluted location in Portugal

    International Nuclear Information System (INIS)

    Godinho, R.M.; Wolterbeek, H.Th.; Verburg, T.; Freitas, M.C.

    2008-01-01

    This experiment compares the short and long time element accumulation behaviour of transplants of Flavoparmelia caperata lichen thalli and total deposition in an atmospheric polluted area. It was found that lichens exposed for a short time behaved differently from lichens in cumulative exposition suggesting the presence of acclimatization behaviour. The lichen transplant elemental content does not unequivocally represent the average or cumulative environmental availability of the exposure period. Reflection characteristics depend on the element and the lichen physiological conditions. Good correlations between lichen elemental contents and total deposition were obtained when a physiological lichen parameter was introduced in a mathematical model, suggesting that metabolically mediated accumulation is important. - The length of the foregoing atmospheric availability period reflected by lichen elemental contents is element-specific and depends on lichen physiological conditions

  8. Barcoding lichen-forming fungi using 454 pyrosequencing is challenged by artifactual and biological sequence variation.

    Science.gov (United States)

    Mark, Kristiina; Cornejo, Carolina; Keller, Christine; Flück, Daniela; Scheidegger, Christoph

    2016-09-01

    Although lichens (lichen-forming fungi) play an important role in the ecological integrity of many vulnerable landscapes, only a minority of lichen-forming fungi have been barcoded out of the currently accepted ∼18 000 species. Regular Sanger sequencing can be problematic when analyzing lichens since saprophytic, endophytic, and parasitic fungi live intimately admixed, resulting in low-quality sequencing reads. Here, high-throughput, long-read 454 pyrosequencing in a GS FLX+ System was tested to barcode the fungal partner of 100 epiphytic lichen species from Switzerland using fungal-specific primers when amplifying the full internal transcribed spacer region (ITS). The present study shows the potential of DNA barcoding using pyrosequencing, in that the expected lichen fungus was successfully sequenced for all samples except one. Alignment solutions such as BLAST were found to be largely adequate for the generated long reads. In addition, the NCBI nucleotide database-currently the most complete database for lichen-forming fungi-can be used as a reference database when identifying common species, since the majority of analyzed lichens were identified correctly to the species or at least to the genus level. However, several issues were encountered, including a high sequencing error rate, multiple ITS versions in a genome (incomplete concerted evolution), and in some samples the presence of mixed lichen-forming fungi (possible lichen chimeras).

  9. The geographical patterns of symbiont diversity in the invasive legume Mimosa pudica can be explained by the competitiveness of its symbionts and by the host genotype.

    Science.gov (United States)

    Melkonian, Rémy; Moulin, Lionel; Béna, Gilles; Tisseyre, Pierre; Chaintreuil, Clémence; Heulin, Karine; Rezkallah, Naïma; Klonowska, Agnieszka; Gonzalez, Sophie; Simon, Marcelo; Chen, Wen-Ming; James, Euan K; Laguerre, Gisèle

    2014-07-01

    Variations in the patterns of diversity of symbionts have been described worldwide on Mimosa pudica, a pan-tropical invasive species that interacts with both α and β-rhizobia. In this study, we investigated if symbiont competitiveness can explain these variations and the apparent prevalence of β- over α-rhizobia. We developed an indirect method to measure the proportion of nodulation against a GFP reference strain and tested its reproducibility and efficiency. We estimated the competitiveness of 54 strains belonging to four species of β-rhizobia and four of α-rhizobia, and the influence of the host genotype on their competitiveness. Our results were compared with biogeographical patterns of symbionts and host varieties. We found: (i) a strong strain effect on competitiveness largely explained by the rhizobial species, with Burkholderia phymatum being the most competitive species, followed by B. tuberum, whereas all other species shared similar and reduced levels of competitiveness; (ii) plant genotype can increase the competitiveness of Cupriavidus taiwanensis. The latter data support the likelihood of the strong adaptation of C. taiwanensis with the M. pudica var. unijuga and help explain its prevalence as a symbiont of this variety over Burkholderia species in some environments, most notably in Taiwan. © 2013 Society for Applied Microbiology and John Wiley & Sons Ltd.

  10. Niche acclimatization in Red Sea corals is dependent on flexibility of host-symbiont association

    KAUST Repository

    Ziegler, Maren

    2015-08-06

    Knowledge of host-symbiont specificity and acclimatization capacity of corals is crucial for understanding implications of environmental change. Whilst some corals have been shown to associate with a number of symbionts that may comprise different physiologies, most corals associate with only one dominant Symbiodinium species at a time. Coral communities in the Red Sea thrive under large fluctuations of environmental conditions, but the degree and mechanisms of coral acclimatization are largely unexplored. Here we investigated the potential for niche acclimatization in 2 dominant corals from the central Red Sea, Pocillopora verrucosa and Porites lutea, in relation to the fidelity of the underlying coral-symbiont association. Repeated sampling over 2 seasons along a cross-shelf and depth gradient revealed a stable symbiont association in P. verrucosa and flexible association in P. lutea. A statistical biological-environmental matching routine revealed that the high plasticity of photophysiology and photopigments in the stable Symbiodinium microadriaticum (type A1) community in P. verrucosa were correlated with environmental influences along spatio-temporal dimensions. In contrast, photophysiology and pigments were less variable within each symbiont type from P. lutea indicating that niche acclimatization was rather regulated by a flexible association with a variable Symbiodinium community. Based on these data, we advocate an extended concept of phenotypic plasticity of the coral holobiont, in which the scleractinian host either associates with a specific Symbiodinium type with a broad physiological tolerance, or the host-symbiont pairing is more flexible to accommodate for different symbiont associations, each adapted to specific environmental settings.

  11. Niche acclimatization in Red Sea corals is dependent on flexibility of host-symbiont association

    KAUST Repository

    Ziegler, Maren; Roder, Cornelia; Bü chel, C; Voolstra, Christian R.

    2015-01-01

    Knowledge of host-symbiont specificity and acclimatization capacity of corals is crucial for understanding implications of environmental change. Whilst some corals have been shown to associate with a number of symbionts that may comprise different physiologies, most corals associate with only one dominant Symbiodinium species at a time. Coral communities in the Red Sea thrive under large fluctuations of environmental conditions, but the degree and mechanisms of coral acclimatization are largely unexplored. Here we investigated the potential for niche acclimatization in 2 dominant corals from the central Red Sea, Pocillopora verrucosa and Porites lutea, in relation to the fidelity of the underlying coral-symbiont association. Repeated sampling over 2 seasons along a cross-shelf and depth gradient revealed a stable symbiont association in P. verrucosa and flexible association in P. lutea. A statistical biological-environmental matching routine revealed that the high plasticity of photophysiology and photopigments in the stable Symbiodinium microadriaticum (type A1) community in P. verrucosa were correlated with environmental influences along spatio-temporal dimensions. In contrast, photophysiology and pigments were less variable within each symbiont type from P. lutea indicating that niche acclimatization was rather regulated by a flexible association with a variable Symbiodinium community. Based on these data, we advocate an extended concept of phenotypic plasticity of the coral holobiont, in which the scleractinian host either associates with a specific Symbiodinium type with a broad physiological tolerance, or the host-symbiont pairing is more flexible to accommodate for different symbiont associations, each adapted to specific environmental settings.

  12. Symbiont dynamics during thermal acclimation using cnidarian-dinoflagellate model holobionts.

    Science.gov (United States)

    Núñez-Pons, Laura; Bertocci, Iacopo; Baghdasarian, Garen

    2017-09-01

    Warming oceans menace reef ecosystems by disrupting symbiosis between cnidarians and Symbiodinium zooxanthellae, thus triggering bleach episodes. Temperature fluctuations promote adjustments in physiological variables and symbiont composition, which can cause stress responses, but can also yield adaptation if fitter host-symbiont homeostasis are achieved. To understand such processes manipulative studies are required, but many reef-building cnidarians pose limitations to experimental prospects. We exposed Exaiptasia anemones to Gradual Thermal Stress (GTS) and Heat Shock (HS) exposures and monitored chlorophyll and symbiont dynamics to test the phenotypic plasticity of these photosynthetic holobionts. GTS enhanced chlorophyll concentrations and decreased Symbiodinium proliferation. A recovery period after GTS returned chlorophyll to lower concentrations and symbiont divisions to higher rates. HS triggered a stress response characterized by intense symbiont declines through degradation and expulsion, algal compensatory proliferation, and chlorophyll accumulation. Anemones pre-exposed to GTS displayed more acute signs of symbiont paucity after HS, demonstrating that recurrent stress does not always induce bleaching-resistance. Our study is the first documenting Symbiodinium C and D, along with the predominant Clade B1 in Exaiptasia anemones. C subclades found in outdoor specimens faded under laboratory exposures. Clade D emerged after HS treatments, and especially after GTS pre-exposure. This highlights the thermotolerance of D subclades found in E. pallida and shows that bleaching-recovery can involve shifts of background symbiont phylotypes. This study enlightens the capability of Exaiptasia anemones to acclimate to gradually increased temperatures, and explores into how thermal history influences in subsequent stress tolerance in symbiotic cnidarians. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Behavior of bacteriome symbionts during transovarial transmission and development of the Asian citrus psyllid.

    Directory of Open Access Journals (Sweden)

    Hiroki Dan

    Full Text Available The Asian citrus psyllid Diaphorina citri Kuwayama (Hemiptera: Liviidae is a serious pest worldwide, transmitting Candidatus Liberibacter spp. (Alphaproteobacteria, the causative agents of a devastating citrus disease known as huanglongbing or greening disease. In a symbiotic organ called the bacteriome, D. citri possesses an organelle-like defensive symbiont, Candidatus Profftella armatura (Betaproteobacteria, and a nutritional symbiont, Ca. Carsonella ruddii (Gammaproteobacteria. Drastically reduced symbiont genomes and metabolic complementarity among the symbionts and D. citri indicate their mutually indispensable association. Moreover, horizontal gene transfer between the Profftella and Liberibacter lineages suggests ecological and evolutionary interactions between the bacteriome symbiont and the HLB pathogen. Using fluorescence in situ hybridization, we examined the behavior of Profftella and Carsonella during transovarial transmission and the development of D. citri. In the bacteriomes of sexually-mature female adults, symbionts transformed from an extremely elongated tubular form into spherical or short-rod forms, which migrated toward the ovary. The symbionts then formed mosaic masses, which entered at the posterior pole of the vitellogenic oocytes. After anatrepsis, Carsonella and Profftella migrated to the central and peripheral parts of the mass, respectively. Following the appearance of host nuclei, the mass cellularized, segregating Carsonella and Profftella in the central syncytium and peripheral uninucleate bacteriocytes, respectively. Subsequently, the uninucleate bacteriocytes harboring Profftella assembled at the posterior pole, while the syncytium, containing Carsonella, sat on the anterior side facing the germ band initiating katatrepsis. During dorsal closure, the syncytium was divided into uninuclear bacteriocytes, which surrounded the mass of bacteriocytes containing Profftella. Once fully surrounded, the bacteriocyte mass

  14. Influence of cell density and phase variants of bacterial symbionts (Xenorhabdus spp.) on dauer juvenile recovery and development of biocontrol nematodes Steinernema carpocapsae and S. feltiae (Nematoda: Rhabditida).

    Science.gov (United States)

    Hirao, A; Ehlers, R-U

    2009-08-01

    The rhabditid nematodes Steinernema carpocapsae and Steinernema feltiae are used in biological control of insect pests. Mass production is done in liquid culture media pre-incubated with their bacterial symbionts Xenorhabdus nematophila and Xenorhabdus bovienii, respectively, before nematode dauer juveniles (DJs) are inoculated. As a response to food signals produced by the bacterial symbionts, the DJs exit from the developmentally arrested dauer stage (they recover development) and grow to adults, which produce DJ offspring. Variable DJ recovery after inoculation often causes process failure due to non-synchronous population development and low numbers of adult nematodes. This contribution investigated the influence of the bacterial cell density on DJ recovery and development to adults. At higher density of 10(10) bacterial cells ml(-1), a higher percentage of DJ recovery was induced, and adults occurred earlier in both Steinernema spp. than at lower density of 10(9) and 10(8) cells ml(-1). Xenorhabdus symbionts produce phase variants. Recovery in bacteria-free supernatants was lower than in supernatants containing bacterial cells for both primary and secondary phase Xenorhabdus spp. and lower in secondary than in primary phase supernatants or cell suspensions. In general, recovery was lower for Steinernema feltiae and the time at which 50% of the population had recovered after exposure to the food signal was longer (RT(50) = 17.1 h) than for Steinernema carpocapsae (RT(50) = 6.6 h). Whereas >90% S. carpocapsae DJs recovered in hemolymph serum of the lepidopteran insect Galleria mellonella, recovery of S. feltiae only reached 31%. Penetration into a host insect prior to exposure to the insect's food signal did not enhance DJ recovery. Consequences for liquid culture mass production of the nematodes and differences between species of the genera Steinernema and Heterorhabditis are discussed.

  15. Lichen Symbiosis: Nature's High Yielding Machines for Induced Hydrogen Production

    Science.gov (United States)

    Papazi, Aikaterini; Kastanaki, Elizabeth; Pirintsos, Stergios; Kotzabasis, Kiriakos

    2015-01-01

    Hydrogen is a promising future energy source. Although the ability of green algae to produce hydrogen has long been recognized (since 1939) and several biotechnological applications have been attempted, the greatest obstacle, being the O2-sensitivity of the hydrogenase enzyme, has not yet been overcome. In the present contribution, 75 years after the first report on algal hydrogen production, taking advantage of a natural mechanism of oxygen balance, we demonstrate high hydrogen yields by lichens. Lichens have been selected as the ideal organisms in nature for hydrogen production, since they consist of a mycobiont and a photobiont in symbiosis. It has been hypothesized that the mycobiont’s and photobiont’s consumption of oxygen (increase of COX and AOX proteins of mitochondrial respiratory pathways and PTOX protein of chrolorespiration) establishes the required anoxic conditions for the activation of the phycobiont’s hydrogenase in a closed system. Our results clearly supported the above hypothesis, showing that lichens have the ability to activate appropriate bioenergetic pathways depending on the specific incubation conditions. Under light conditions, they successfully use the PSII-dependent and the PSII-independent pathways (decrease of D1 protein and parallel increase of PSaA protein) to transfer electrons to hydrogenase, while under dark conditions, lichens use the PFOR enzyme and the dark fermentative pathway to supply electrons to hydrogenase. These advantages of lichen symbiosis in combination with their ability to survive in extreme environments (while in a dry state) constitute them as unique and valuable hydrogen producing natural factories and pave the way for future biotechnological applications. PMID:25826211

  16. Lichen symbiosis: nature's high yielding machines for induced hydrogen production.

    Directory of Open Access Journals (Sweden)

    Aikaterini Papazi

    Full Text Available Hydrogen is a promising future energy source. Although the ability of green algae to produce hydrogen has long been recognized (since 1939 and several biotechnological applications have been attempted, the greatest obstacle, being the O2-sensitivity of the hydrogenase enzyme, has not yet been overcome. In the present contribution, 75 years after the first report on algal hydrogen production, taking advantage of a natural mechanism of oxygen balance, we demonstrate high hydrogen yields by lichens. Lichens have been selected as the ideal organisms in nature for hydrogen production, since they consist of a mycobiont and a photobiont in symbiosis. It has been hypothesized that the mycobiont's and photobiont's consumption of oxygen (increase of COX and AOX proteins of mitochondrial respiratory pathways and PTOX protein of chrolorespiration establishes the required anoxic conditions for the activation of the phycobiont's hydrogenase in a closed system. Our results clearly supported the above hypothesis, showing that lichens have the ability to activate appropriate bioenergetic pathways depending on the specific incubation conditions. Under light conditions, they successfully use the PSII-dependent and the PSII-independent pathways (decrease of D1 protein and parallel increase of PSaA protein to transfer electrons to hydrogenase, while under dark conditions, lichens use the PFOR enzyme and the dark fermentative pathway to supply electrons to hydrogenase. These advantages of lichen symbiosis in combination with their ability to survive in extreme environments (while in a dry state constitute them as unique and valuable hydrogen producing natural factories and pave the way for future biotechnological applications.

  17. Determination of natural radionuclides in lichen samples of Carnoparmelia Texana

    International Nuclear Information System (INIS)

    Alencar, Marcos M.; Damatto, Sandra R.; Mazzilli, Barbara P.

    2009-01-01

    Lichen plays an important role in studies of environmental pollution. It can be used for the evaluation of air contaminants, including heavy metals and radionuclides. The main objective of this study is to verify the possibility of using the lichen species Canoparmelia Texana for the assessment of natural radionuclides of the U and Th decay series in air in the vicinity of Instituto de Pesquisas Energeticas e Nucleares (IPEN) installations. IPEN has as major activity to perform research in the field of the nuclear fuel cycle, and therefore deals with natural radionuclides of the U and Th series. The content of 238 U, 234 U, 230 Th, 210 Po and 232 Th in lichen samples were determined by alpha spectrometry after a radiochemical separation. Ra isotopes and 210 Pb were determined by gross alpha and beta counting after a radiochemical separation and measurement on a low background gas flow proportional detector. The results obtained for 238 U varied from 2.4 ± 0.4 Bq kg -1 to 6.6 ± 0.1 Bq kg -1 and from 4.4 ± 0.3 Bq kg -1 to 12.1 ± 2.6 Bq kg -1 , for 232 Th. For 226 Ra varied from 13 ± 1 Bq kg -1 to 38 ± 2 Bq kg -1 and from 200 ± 13 Bq kg -1 to 351 ± 12 Bqkg -1 for 228 Ra. The results obtained were compared with data obtained for the same radionuclides in lichen samples in an area affected by TENORM industry and can be considered as background for this lichen species. It can be concluded that the control of atmospheric discharges of IPEN facilities has been effective along the years, giving no evidence of radiological environmental impact. (author)

  18. New higher taxa in the lichen family Graphidaceae (lichenized Ascomycota: Ostropales) based on a three-gene skeleton phylogeny

    Science.gov (United States)

    H. Thorsten Lumbsch; Ekaphan Kraichak; Sittiporn Parnmen; Eimy Rivas Plata; Andre Aptroot; Marcela E.S. Caceres; Damien Ertz; Shirley Cunha Feuerstein; Joel A. Mercado-Diaz; Bettina Staiger; Dries Van den Broeck; Robert. Lücking

    2014-01-01

    We provide an updated skeleton phylogeny of the lichenized family Graphidaceae (excluding subfamily Gomphilloideae), based on three loci (mtSSU, nuLSU, RPB2), to elucidate the position of four new genera, Aggregatorygma, Borinquenotrema, Corticorygma, and Paratopeliopsis, as well as the placement of the enigmatic species Diorygma erythrellum, Fissurina monilifera, and...

  19. Recent Invasion of the Symbiont-Bearing Foraminifera Pararotalia into the Eastern Mediterranean Facilitated by the Ongoing Warming Trend.

    Science.gov (United States)

    Schmidt, Christiane; Morard, Raphael; Almogi-Labin, Ahuva; Weinmann, Anna E; Titelboim, Danna; Abramovich, Sigal; Kucera, Michal

    2015-01-01

    The eastern Mediterranean is a hotspot of biological invasions. Numerous species of Indo-pacific origin have colonized the Mediterranean in recent times, including tropical symbiont-bearing foraminifera. Among these is the species Pararotalia calcariformata. Unlike other invasive foraminifera, this species was discovered only two decades ago and is restricted to the eastern Mediterranean coast. Combining ecological, genetic and physiological observations, we attempt to explain the recent invasion of this species in the Mediterranean Sea. Using morphological and genetic data, we confirm the species attribution to P. calcariformata McCulloch 1977 and identify its symbionts as a consortium of diatom species dominated by Minutocellus polymorphus. We document photosynthetic activity of its endosymbionts using Pulse Amplitude Modulated Fluorometry and test the effects of elevated temperatures on growth rates of asexual offspring. The culturing of asexual offspring for 120 days shows a 30-day period of rapid growth followed by a period of slower growth. A subsequent 48-day temperature sensitivity experiment indicates a similar developmental pathway and high growth rate at 28°C, whereas an almost complete inhibition of growth was observed at 20°C and 35°C. This indicates that the offspring of this species may have lower tolerance to cold temperatures than what would be expected for species native to the Mediterranean. We expand this hypothesis by applying a Species Distribution Model (SDM) based on modern occurrences in the Mediterranean using three environmental variables: irradiance, turbidity and yearly minimum temperature. The model reproduces the observed restricted distribution and indicates that the range of the species will drastically expand westwards under future global change scenarios. We conclude that P. calcariformata established a population in the Levant because of the recent warming in the region. In line with observations from other groups of organisms

  20. Recent Invasion of the Symbiont-Bearing Foraminifera Pararotalia into the Eastern Mediterranean Facilitated by the Ongoing Warming Trend.

    Directory of Open Access Journals (Sweden)

    Christiane Schmidt

    Full Text Available The eastern Mediterranean is a hotspot of biological invasions. Numerous species of Indo-pacific origin have colonized the Mediterranean in recent times, including tropical symbiont-bearing foraminifera. Among these is the species Pararotalia calcariformata. Unlike other invasive foraminifera, this species was discovered only two decades ago and is restricted to the eastern Mediterranean coast. Combining ecological, genetic and physiological observations, we attempt to explain the recent invasion of this species in the Mediterranean Sea. Using morphological and genetic data, we confirm the species attribution to P. calcariformata McCulloch 1977 and identify its symbionts as a consortium of diatom species dominated by Minutocellus polymorphus. We document photosynthetic activity of its endosymbionts using Pulse Amplitude Modulated Fluorometry and test the effects of elevated temperatures on growth rates of asexual offspring. The culturing of asexual offspring for 120 days shows a 30-day period of rapid growth followed by a period of slower growth. A subsequent 48-day temperature sensitivity experiment indicates a similar developmental pathway and high growth rate at 28°C, whereas an almost complete inhibition of growth was observed at 20°C and 35°C. This indicates that the offspring of this species may have lower tolerance to cold temperatures than what would be expected for species native to the Mediterranean. We expand this hypothesis by applying a Species Distribution Model (SDM based on modern occurrences in the Mediterranean using three environmental variables: irradiance, turbidity and yearly minimum temperature. The model reproduces the observed restricted distribution and indicates that the range of the species will drastically expand westwards under future global change scenarios. We conclude that P. calcariformata established a population in the Levant because of the recent warming in the region. In line with observations from other

  1. Differential responses of the coral host and their algal symbiont to thermal stress.

    Directory of Open Access Journals (Sweden)

    William Leggat

    Full Text Available The success of any symbiosis under stress conditions is dependent upon the responses of both partners to that stress. The coral symbiosis is particularly susceptible to small increases of temperature above the long term summer maxima, which leads to the phenomenon known as coral bleaching, where the intracellular dinoflagellate symbionts are expelled. Here we for the first time used quantitative PCR to simultaneously examine the gene expression response of orthologs of the coral Acropora aspera and their dinoflagellate symbiont Symbiodinium. During an experimental bleaching event significant up-regulation of genes involved in stress response (HSP90 and HSP70 and carbon metabolism (glyceraldehyde-3-phosphate dehydrogenase, α-ketoglutarate dehydrogenase, glycogen synthase and glycogen phosphorylase from the coral host were observed. In contrast in the symbiont, HSP90 expression decreased, while HSP70 levels were increased on only one day, and only the α-ketoglutarate dehydrogenase expression levels were found to increase. In addition the changes seen in expression patterns of the coral host were much larger, up to 10.5 fold, compared to the symbiont response, which in all cases was less than 2-fold. This targeted study of the expression of key metabolic and stress genes demonstrates that the response of the coral and their symbiont vary significantly, also a response in the host transcriptome was observed prior to what has previously been thought to be the temperatures at which thermal stress events occur.

  2. Orally Delivered Scorpion Antimicrobial Peptides Exhibit Activity against Pea Aphid (Acyrthosiphon pisum) and Its Bacterial Symbionts.

    Science.gov (United States)

    Luna-Ramirez, Karen; Skaljac, Marisa; Grotmann, Jens; Kirfel, Phillipp; Vilcinskas, Andreas

    2017-08-24

    Aphids are severe agricultural pests that damage crops by feeding on phloem sap and vectoring plant pathogens. Chemical insecticides provide an important aphid control strategy, but alternative and sustainable control measures are required to avoid rapidly emerging resistance, environmental contamination, and the risk to humans and beneficial organisms. Aphids are dependent on bacterial symbionts, which enable them to survive on phloem sap lacking essential nutrients, as well as conferring environmental stress tolerance and resistance to parasites. The evolution of aphids has been accompanied by the loss of many immunity-related genes, such as those encoding antibacterial peptides, which are prevalent in other insects, probably because any harm to the bacterial symbionts would inevitably affect the aphids themselves. This suggests that antimicrobial peptides (AMPs) could replace or at least complement conventional insecticides for aphid control. We fed the pea aphids ( Acyrthosiphon pisum ) with AMPs from the venom glands of scorpions. The AMPs reduced aphid survival, delayed their reproduction, displayed in vitro activity against aphid bacterial symbionts, and reduced the number of symbionts in vivo. Remarkably, we found that some of the scorpion AMPs compromised the aphid bacteriome, a specialized organ that harbours bacterial symbionts. Our data suggest that scorpion AMPs holds the potential to be developed as bio-insecticides, and are promising candidates for the engineering of aphid-resistant crops.

  3. Orally Delivered Scorpion Antimicrobial Peptides Exhibit Activity against Pea Aphid (Acyrthosiphon pisum and Its Bacterial Symbionts

    Directory of Open Access Journals (Sweden)

    Karen Luna-Ramirez

    2017-08-01

    Full Text Available Aphids are severe agricultural pests that damage crops by feeding on phloem sap and vectoring plant pathogens. Chemical insecticides provide an important aphid control strategy, but alternative and sustainable control measures are required to avoid rapidly emerging resistance, environmental contamination, and the risk to humans and beneficial organisms. Aphids are dependent on bacterial symbionts, which enable them to survive on phloem sap lacking essential nutrients, as well as conferring environmental stress tolerance and resistance to parasites. The evolution of aphids has been accompanied by the loss of many immunity-related genes, such as those encoding antibacterial peptides, which are prevalent in other insects, probably because any harm to the bacterial symbionts would inevitably affect the aphids themselves. This suggests that antimicrobial peptides (AMPs could replace or at least complement conventional insecticides for aphid control. We fed the pea aphids (Acyrthosiphon pisum with AMPs from the venom glands of scorpions. The AMPs reduced aphid survival, delayed their reproduction, displayed in vitro activity against aphid bacterial symbionts, and reduced the number of symbionts in vivo. Remarkably, we found that some of the scorpion AMPs compromised the aphid bacteriome, a specialized organ that harbours bacterial symbionts. Our data suggest that scorpion AMPs holds the potential to be developed as bio-insecticides, and are promising candidates for the engineering of aphid-resistant crops.

  4. Co-niche construction between hosts and symbionts: ideas and evidence.

    Science.gov (United States)

    Borges, Renee M

    2017-07-01

    Symbiosis is a process that can generate evolutionary novelties and can extend the phenotypic niche space of organisms. Symbionts can act together with their hosts to co-construct host organs, within which symbionts are housed. Once established within hosts, symbionts can also influence various aspects of host phenotype, such as resource acquisition, protection from predation by acquisition of toxicity, as well as behaviour. Once symbiosis is established, its fidelity between generations must be ensured. Hosts evolve various mechanisms to screen unwanted symbionts and to facilitate faithful transmission of mutualistic partners between generations. Microbes are the most important symbionts that have influenced plant and animal phenotypes; multicellular organisms engage in developmental symbioses with microbes at many stages in ontogeny. The co-construction of niches may result in composite organisms that are physically nested within each other. While it has been advocated that these composite organisms need new evolutionary theories and perspectives to describe their properties and evolutionary trajectories, it appears that standard evolutionary theories are adequate to explore selection pressures on their composite or individual traits. Recent advances in our understanding of composite organisms open up many important questions regarding the stability and transmission of these units.

  5. Cyanobacterial diversity and a new acaryochloris-like symbiont from Bahamian sea-squirts.

    Directory of Open Access Journals (Sweden)

    Susanna López-Legentil

    Full Text Available Symbiotic interactions between ascidians (sea-squirts and microbes are poorly understood. Here we characterized the cyanobacteria in the tissues of 8 distinct didemnid taxa from shallow-water marine habitats in the Bahamas Islands by sequencing a fragment of the cyanobacterial 16S rRNA gene and the entire 16S-23S rRNA internal transcribed spacer region (ITS and by examining symbiont morphology with transmission electron (TEM and confocal microscopy (CM. As described previously for other species, Trididemnum spp. mostly contained symbionts associated with the Prochloron-Synechocystis group. However, sequence analysis of the symbionts in Lissoclinum revealed two unique clades. The first contained a novel cyanobacterial clade, while the second clade was closely associated with Acaryochloris marina. CM revealed the presence of chlorophyll d (chl d and phycobiliproteins (PBPs within these symbiont cells, as is characteristic of Acaryochloris species. The presence of symbionts was also observed by TEM inside the tunic of both the adult and larvae of L. fragile, indicating vertical transmission to progeny. Based on molecular phylogenetic and microscopic analyses, Candidatus Acaryochloris bahamiensis nov. sp. is proposed for this symbiotic cyanobacterium. Our results support the hypothesis that photosymbiont communities in ascidians are structured by host phylogeny, but in some cases, also by sampling location.

  6. The applicability of lichens as retrospective biomonitors of the radioactive contamination in a mountain ecosystem

    International Nuclear Information System (INIS)

    Gastberger, M.; Hofmann, W.; Tuerk, R.

    1996-01-01

    A number of previous studies have demonstrated that lichens are suitable and inexpensive biological detectors of the local fallout pattern. Lichens are usually highly contaminated and their contamination correlates well with the soil deposition data. One of their major advantages is that samples can easily be collected from quite large areas, thereby getting an average contamination of this area. Especially in mountain ecosystems, lichens could gain great importance as biomonitors, because many lichens grow in this area and, moreover, the collection of soil samples may be very difficult in these elevated regions. On the other hand, particularly in mountainous regions, the deposited radionuclide activities may vary considerably from site to site due to specific local meteorological conditions, which may also affect the growth of lichens and their uptake of radionuclides. Thus the goal of this study was to find out, whether lichens are still suitable biological detectors of the local radioactive contamination pattern several years after the initial deposition event

  7. Lichen planus and other lichenoid dermatoses: Kids are not just little people.

    Science.gov (United States)

    Payette, Michael J; Weston, Gillian; Humphrey, Stephen; Yu, JiaDe; Holland, Kristen E

    2015-01-01

    Lichenoid dermatoses, a group of inflammatory skin conditions with characteristic clinical and histopathologic findings, range from common to rare. Classic lichen planus typically presents as pruritic, polygonal, violaceous flat-topped papules and plaques; many variants in morphology and location also exist. Other lichenoid dermatoses share similar clinical presentations and histopathologic findings. These include lichenoid drug eruption, lichen planus-like keratosis, lichen striatus, lichen nitidus, and keratosis lichenoides chronica. Epidemiologic characteristics vary among each lichenoid disorder. While classic lichen planus is considered a disease of adults, other lichenoid dermatoses may be more common in younger populations. The literature contains an array of reports on the variations in presentation and successful management of lichen planus and lichenoid dermatoses among diverse populations. Familiarity with the characteristics of each lichenoid dermatosis, rare or common within each patient population, is key to accomplishing timely recognition and effective management. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. Parallel metatranscriptome analyses of host and symbiont gene expression in the gut of the termite Reticulitermes flavipes

    Directory of Open Access Journals (Sweden)

    Zhou Xuguo

    2009-10-01

    Full Text Available Abstract Background Termite lignocellulose digestion is achieved through a collaboration of host plus prokaryotic and eukaryotic symbionts. In the present work, we took a combined host and symbiont metatranscriptomic approach for investigating the digestive contributions of host and symbiont in the lower termite Reticulitermes flavipes. Our approach consisted of parallel high-throughput sequencing from (i a host gut cDNA library and (ii a hindgut symbiont cDNA library. Subsequently, we undertook functional analyses of newly identified phenoloxidases with potential importance as pretreatment enzymes in industrial lignocellulose processing. Results Over 10,000 expressed sequence tags (ESTs were sequenced from the 2 libraries that aligned into 6,555 putative transcripts, including 171 putative lignocellulase genes. Sequence analyses provided insights in two areas. First, a non-overlapping complement of host and symbiont (prokaryotic plus protist glycohydrolase gene families known to participate in cellulose, hemicellulose, alpha carbohydrate, and chitin degradation were identified. Of these, cellulases are contributed by host plus symbiont genomes, whereas hemicellulases are contributed exclusively by symbiont genomes. Second, a diverse complement of previously unknown genes that encode proteins with homology to lignase, antioxidant, and detoxification enzymes were identified exclusively from the host library (laccase, catalase, peroxidase, superoxide dismutase, carboxylesterase, cytochrome P450. Subsequently, functional analyses of phenoloxidase activity provided results that were strongly consistent with patterns of laccase gene expression. In particular, phenoloxidase activity and laccase gene expression are mostly restricted to symbiont-free foregut plus salivary gland tissues, and phenoloxidase activity is inducible by lignin feeding. Conclusion To our knowledge, this is the first time that a dual host-symbiont transcriptome sequencing effort

  9. Influence of air pollutants (SO/sub 2/) upon transplanted lichen

    Energy Technology Data Exchange (ETDEWEB)

    Schonbeck, H

    1968-01-01

    The subject of air pollution and its effects on lichens is addressed. Attention is focused on the effects of sulfur dioxide on Parmelia physodes in a heavily forested area surrounding an iron ore smelter at Biersdorf (Siegerland). The sulfur dioxide content of the air was determined in an intermittent manner at varying distances from the smelter. Depending upon the amount of sulfur dioxide, varying degrees of damage to the lichens were noted. At locations with the highest average concentrations, the lichens died.

  10. Lichen flora around the Korean Antarctic Scientific Station, King George Island, Antarctic.

    Science.gov (United States)

    Kim, Ji Hee; Ahn, In-Young; Hong, Soon Gyu; Andreev, Mikhail; Lim, Kwang-Mi; Oh, Mi Jin; Koh, Young Jin; Hur, Jae-Seoun

    2006-10-01

    As part of the long-term monitoring projects on Antarctic terrestrial vegetation in relation to global climate change, a lichen floristical survey was conducted around the Korean Antarctic Station (King Sejong Station), which is located on Barton Peninsula, King George Island, in January and February of 2006. Two hundred and twenty-five lichen specimens were collected and sixty-two lichen species in 38 genera were identified by morphological characteristics, chemical constituents, TLC analysis and ITS nucleotide sequence analysis.

  11. Mapping lichen color-groups in western Arctic Alaska using seasonal Landsat composites

    Science.gov (United States)

    Nelson, P.; Macander, M. J.; Swingley, C. S.

    2016-12-01

    Mapping lichens at a landscape scale has received increased recent interest due to fears that terricolous lichen mats, primary winter caribou forage, may be decreasing across the arctic and boreal zones. However, previous efforts have produced taxonomically coarse, total lichen cover maps or have covered relatively small spatial extents. Here we attempt to map lichens of differing colors as species proxies across northwestern Alaska to produce the finest taxonomic and spatial- grained lichen maps covering the largest spatial extent to date. Lichen community sampling in five western Alaskan National Parks and Preserves from 2007-2012 generated 328 FIA-style 34.7 m radius plots on which species-level macrolichen community structure and abundance was estimated. Species were coded by color and plot lichen cover was aggregated by plot as the sum of the cover of each species in a color group. Ten different lichen color groupings were used for modeling to deduce which colors were most detectable. Reflectance signatures of each plot were extracted from a series of Landsat composites (circa 2000-2010) partitioned into two-week intervals from June 1 to Sept. 15. Median reflectance values for each band in each pixel were selected based on filtering criteria to reduce likelihood of snow cover. Lichen color group cover was regressed against plot reflectance plus additional abiotic predictors in two different data mining algorithms. Brown and grey lichens had the best models explaining approximately 40% of lichen cover in those color groups. Both data mining techniques produced similarly good fitting models. Spatial patterns of lichen color-group cover show distinctly different ecological patterns of these color-group species proxies.

  12. Epiphytic lichens as indicators of air pollution in Tomsk Oblast (Russia)

    International Nuclear Information System (INIS)

    TomskNIPIneft, Tomsk (Russian Federation))" data-affiliation=" (JSC TomskNIPIneft, Tomsk (Russian Federation))" >Bolshunova, T S; Rikhvanov, L P; Mezhibor, A M

    2014-01-01

    This research presents the data on concentrations of 28 chemical elements in the ash of lichens growing in Tomsk Oblast where different industrial enterprises are located. In the sites of oil and gas exploration complex the lichens contain higher concentrations of Sc, Fe, Cr, Zn, As, Br, Rb, Ba, and Au in comparison with the background values. In the zone of Tomsk- Seversk industrial agglomeration the lichens accumulate Ca, Sr, Sb, Th, U, and lanthanides

  13. Lichen Monitoring Delineates Biodiversity on a Great Barrier Reef Coral Cay

    OpenAIRE

    Rogers, Paul C.; Rogers, Roderick W.; Hedrich, Anne E.; Moss, Patrick T.

    2015-01-01

    Coral islands around the world are threatened by changing climates. Rising seas, drought, and increased tropical storms are already impacting island ecosystems. We aim to better understand lichen community ecology of coral island forests. We used an epiphytic lichen community survey to gauge Pisonia (Pisonia grandis R.BR.), which dominates forest conditions on Heron Island, Australia. Nine survey plots were sampled for lichen species presence and abundance, all tree diameters and species, GPS...

  14. Association of coral algal symbionts with a diverse viral community responsive to heat shock

    KAUST Repository

    Brüwer, Jan D.

    2017-08-17

    Stony corals provide the structural foundation of coral reef ecosystems and are termed holobionts given they engage in symbioses, in particular with photosynthetic dinoflagellates of the genus Symbiodinium. Besides Symbiodinium, corals also engage with bacteria affecting metabolism, immunity, and resilience of the coral holobiont, but the role of associated viruses is largely unknown. In this regard, the increase of studies using RNA sequencing (RNA-Seq) to assess gene expression provides an opportunity to elucidate viral signatures encompassed within the data via careful delineation of sequence reads and their source of origin.Here, we re-analyzed an RNA-Seq dataset from a cultured coral symbiont (Symbiodinium microadriaticum, Clade A1) across four experimental treatments (control, cold shock, heat shock, dark shock) to characterize associated viral diversity, abundance, and gene expression. Our approach comprised the filtering and removal of host sequence reads, subsequent phylogenetic assignment of sequence reads of putative viral origin, and the assembly and analysis of differentially expressed viral genes. About 15.46% (123 million) of all sequence reads were non-host-related, of which <1% could be classified as archaea, bacteria, or virus. Of these, 18.78% were annotated as virus and comprised a diverse community consistent across experimental treatments. Further, non-host related sequence reads assembled into 56,064 contigs, including 4856 contigs of putative viral origin that featured 43 differentially expressed genes during heat shock. The differentially expressed genes included viral kinases, ubiquitin, and ankyrin repeat proteins (amongst others), which are suggested to help the virus proliferate and inhibit the algal host\\'s antiviral response.Our results suggest that a diverse viral community is associated with coral algal endosymbionts of the genus Symbiodinium, which prompts further research on their ecological role in coral health and resilience.

  15. Heavy metal content of lichens in relation to distance from a nickel smelter in Sudbury, Ontario

    Energy Technology Data Exchange (ETDEWEB)

    Nieboer, E; Ahmed, H M; Puckett, K J; Richardson, D H.S.

    1972-01-01

    The Sudbury region of Ontario has large deposits of nickel, iron, and copper, and thus a number of smelting plants which produce sulfur dioxide and heavy metal pollution. Since lichens are good indicators of SO/sub 2/ pollution levels, the pattern of heavy metal content in lichen species in the area of a copper smelter in Sudbury was correlated with distance from the smelter to ascertain whether lichens might also be good indicators of the amount of heavy metal fallout. The lichens were analyzed qualitatively and quantitatively. All seven species of lichens contained copper, iron, zinc, nickel, manganese, and lead. Cadmium and cobalt were detected in two species. Neither gold nor silver could be identified in lichen material with the tests used. A pollution model was developed and compared to field results. The simple dilution of the stack effluent was consistent with the fact that the lichen metal content was related to the reciprocal of the distance from the pollution source. The lichens from the area could tolerate simultaneously high concentrations of several heavy metals that are known to be toxic to other plants. The mechanism of metal uptake was not clearly established. The study showed that lichens and other epiphytes are potentially the most useful indicators of heavy metal fallout around industrial plants.

  16. The lichens in the agricultural landscape of Podlasie, North East Poland

    International Nuclear Information System (INIS)

    Matwiejuk, A.

    2016-01-01

    This paper carries information for diagnosis lichenobiota in the agricultural landscape of Poland NE. The research led to a better understanding of the problem of occurrence of lichens in the agricultural landscape. The functional groups of lichens, which were used to characterize lichen biota taking into account the morphological forms, frequency of occurrence and habitat requirements were determined. The basis for the specification of the more interesting taxa in the study area was to analyze the species composition of lichens in relation to the data on their previous records in rural areas, the degree of recognition in Poland NE and conservation status and threats in the country. (author)

  17. Lichens as bioindicators of air quality in Dimitrovgrad (South-Eastern Serbia

    Directory of Open Access Journals (Sweden)

    Stamenković S.

    2010-01-01

    Full Text Available Air pollution detection in Dimitrovgrad has not been done yet. In this work different lichen have been used as a bioindication to establish different air pollution levels. At 18 investigated points 22 lichen taxa have been found. Using the Index of Atmospheric Purity (IAP it has been found that there are 3 different air pollution zones in Dimitrovgrad: 'lichen desert', 'transitional' and 'normal zone'. The most sensitive lichen taxa in Dimitrovgrad are Evernia prunastra, Ochrolechia pallescens, Parmelia sulcata, and Physcia tenella and the most tolerant are Phaeophyscia orbicularis, Physcia adscendens, Physconia distorta, Physconia grisea, and Xanthoria parietina. .

  18. Lichen physiological traits and growth forms affect communities of associated invertebrates.

    Science.gov (United States)

    Bokhorst, Stef; Asplund, Johan; Kardol, Paul; Wardle, David A

    2015-09-01

    While there has been much interest in the relationships between traits of primary producers and composition of associated invertebrate consumer communities, our knowledge is largely based on studies from vascular plants, while other types of functionally important producers, such as lichens, have rarely been considered. To address how physiological traits of lichens drive community composition of invertebrates, we collected thalli from 27 lichen species from southern Norway and quantified the communities of associated springtails, mites, and nematodes. For each lichen species, we measured key physiological thallus traits and determined whether invertebrate communities were correlated with these traits. We also explored whether invertebrate communities differed among lichen groups, categorized according to nitrogen-fixing ability, growth form, and substratum. Lichen traits explained up to 39% of the variation in abundances of major invertebrate groups. For many invertebrate groups, abundance was positively correlated with lichen N and P concentrations, N:P ratio, and the percentage of water content on saturation (WC), but had few relationships with concentrations of carbon-based secondary compounds. Diversity and taxonomic richness of invertebrate groups were sometimes also correlated with lichen N and N:P ratios. Nitrogen-fixing lichens showed higher abundance and diversity of some invertebrate groups than did non-N-fixing lichens. However, this emerged in part because most N-fixing lichens have a foliose growth form that benefits invertebrates, through, improving the microclimate, independently of N concentration. Furthermore, invertebrate communities associated with terricolous lichens were determined more by their close proximity to the soil invertebrate pool than by lichen traits. Overall, our results reveal that differences between lichen species have a large impact on the invertebrate communities that live among the thalli. Different invertebrate groups show

  19. The comparative analysis of dermatoscopy picture of lichen planus and psoriasis

    Directory of Open Access Journals (Sweden)

    Sherstobitova K.Yu.

    2016-09-01

    Full Text Available Aim: analysis of different dermatoscopic patterns of lichen planus and psoriasis. Material and methods. We observed 80 patients: 40 with psoriasis, 40 — with lichen planus. Dermatoscopic study was conducted using video-dermatoscope of expert class "MoleMaxHD" (Derma Medical Systems company, Austria, under magnification from хЗО to x80. Results. Comparing the dermotoscopic findings of psoriatic plaque and lichen planus, vascular features were found to be more significant in psoriasis and in lichen planus non-vascular features were more prominant. Conclusion. Dermoscopy can be successfully used in differential diagnosis of these dermatoses.

  20. Relationship between atmospheric ammonia concentration and nitrogen content in terricolous lichen (Cladonia portentosa)

    DEFF Research Database (Denmark)

    Nielsen, Knud Erik; Andersen, Helle Vibeke; Strandberg, Morten Tune

    2014-01-01

    From April 2006 to April 2007, the geographical and seasonal variation in nitrogen content in terricolous lichen (Cladonia portentosa) and atmospheric ammonia concentrations were measured at five heathland sites. The seasonal variation in the nitrogen content of the lichen was small, even though...... there was a large seasonal variation in the air concentration of ammonia. A sizable local variation in the nitrogen content of the lichen was found even at the scale of a few kilometres. The nitrogen content in the lichen showed a high correlation to the yearly mean value of the measured ammonia concentration...

  1. Treatment of recalcitrant erosive oral lichen planus and desquamative gingivitis with oral apremilast.

    Science.gov (United States)

    AbuHilal, Mohn'd; Walsh, Scott; Shear, Neil

    2016-11-30

    Erosive oral lichen planus and desquamative gingivitis are uncommon but severe debilitating variants of oral lichen planus. Treatment of these presentations is difficult and challenging. A 44-year-old woman was referred to the dermatology clinic with chronic painful lichen planus-related gingivitis and buccal erosions. She has failed multiple treatments including topical clobetasol and tacrolimus, intralesional corticosteroids and several systemic and immunosuppressive agents. Following completion of three months of treatment with oral apremilast at a dose of 30 mg twice daily, significant improvement was noted in her disease activity. Oral apremilast may be a safe and effective treatment for erosive oral lichen planus.

  2. Squamous Cell Carcinoma Arising in Hypertrophic Lichen Planus: A Review and Analysis of 38 Cases.

    Science.gov (United States)

    Knackstedt, Thomas J; Collins, Lindsey K; Li, Zhongze; Yan, Shaofeng; Samie, Faramarz H

    2015-12-01

    Hypertrophic lichen planus is a chronic variant of lichen planus with controversial malignant association. To describe and analyze the relationship of squamous cell carcinoma (SCC) and hypertrophic lichen planus. A retrospective chart review of patients with hypertrophic lichen planus and SCC was performed at the authors' institution. Thereafter, scientific databases were searched for articles reporting cases of SCC arising in hypertrophic lichen planus. Patient demographics, immune status, lichen planus features, and SCC data points were extracted for each patient and evaluated. Thirty-eight cases of SCC in hypertrophic lichen planus occurred in 16 women, average age: 61.4, and 22 men, average age: 51.3, after a lag time of 88 days to 40 years. Squamous cell carcinoma was uniformly located on the lower extremity. Men had larger SCC than women (p = .027) and a significantly longer lag time to SCC development (p = .002). Long lag time was associated with a smaller SCC size (p = .032). In the past, hypertrophic lichen planus and SCC have been considered isolated diseases. Based on an increasing number of cases, the association between hypertrophic lichen planus and keratinocyte malignancies warrants surveillance.

  3. Squamous cell carcinoma developing in a cutaneous lichen planus lesion: a rare case.

    Science.gov (United States)

    Ghosh, Saptarshi; Kotne, Sivasankar; Ananda Rao, P B; Turlapati, S P V; Kumar Soren, Dillip

    2014-01-01

    Lichen planus is a benign disorder characterized by an itchy, noninfectious skin rash. Though lichen planus is a common papulosquamous disorder affecting about 1-2% of the population, neoplastic transformation of cutaneous lichen planus lesions occurs very rarely and should be borne in mind while treating nonhealing longstanding lesions of lichen planus. Studies suggest an estimated 0.3-3% risk of malignancy in patients with oral lichen planus, however, cutaneous lichen planus does not carry an increased risk of malignant degeneration. We present a case of a 36-year-old male with a 10-year-long history of hypertrophic lichen planus who presented with a nonhealing ulcer in the left popliteal fossa. The patient underwent wide local excision with superficial skin grafting. Postoperative histopathological examination revealed verrucous squamous cell carcinoma complicating lichen planus. In view of underlying structure involvement, adjuvant radiation therapy was given. This case is being reported to emphasize the infrequent possibility of development of malignancy in cutaneous lichen planus, especially if it presents as a longstanding, nonhealing, itchy lesion with patchy areas of depigmentation in the lower limbs.

  4. Mixed infections may promote diversification of mutualistic symbionts: why are there ineffective rhizobia?

    Science.gov (United States)

    Friesen, M L; Mathias, A

    2010-02-01

    While strategy variation is a key feature of symbiotic mutualisms, little work focuses on the origin of this diversity. Rhizobia strategies range from mutualistic nitrogen fixers to parasitic nonfixers that hoard plant resources to increase their own survival in soil. Host plants reward beneficial rhizobia with higher nodule growth rates, generating a trade-off between reproduction in nodules and subsequent survival in soil. However, hosts might not discriminate between strains in mixed infections, allowing nonfixing strains to escape sanctions. We construct an adaptive dynamics model of symbiotic nitrogen-fixation and find general situations where symbionts undergo adaptive diversification, but in most situations complete nonfixers do not evolve. Social conflict in mixed infections when symbionts face a survival-reproduction trade-off can drive the origin of some coexisting symbiont strategies, where less mutualistic strains exploit benefits generated by better mutualists.

  5. Plant-mediated interspecific horizontal transmission of an intracellular symbiont in insects

    KAUST Repository

    Gonella, Elena

    2015-11-13

    Intracellular reproductive manipulators, such as Candidatus Cardinium and Wolbachia are vertically transmitted to progeny but rarely show co-speciation with the host. In sap-feeding insects, plant tissues have been proposed as alternative horizontal routes of interspecific transmission, but experimental evidence is limited. Here we report results from experiments that show that Cardinium is horizontally transmitted between different phloem sap-feeding insect species through plants. Quantitative PCR and in situ hybridization experiments indicated that the leafhopper Scaphoideus titanus releases Cardinium from its salivary glands during feeding on both artificial media and grapevine leaves. Successional time-course feeding experiments with S. titanus initially fed sugar solutions or small areas of grapevine leaves followed by feeding by the phytoplasma vector Macrosteles quadripunctulatus or the grapevine feeder Empoasca vitis revealed that the symbionts were transmitted to both species. Explaining interspecific horizontal transmission through plants improves our understanding of how symbionts spread, their lifestyle and the symbiont-host intermixed evolutionary pattern.

  6. Plant-mediated interspecific horizontal transmission of an intracellular symbiont in insects.

    Science.gov (United States)

    Gonella, Elena; Pajoro, Massimo; Marzorati, Massimo; Crotti, Elena; Mandrioli, Mauro; Pontini, Marianna; Bulgari, Daniela; Negri, Ilaria; Sacchi, Luciano; Chouaia, Bessem; Daffonchio, Daniele; Alma, Alberto

    2015-11-13

    Intracellular reproductive manipulators, such as Candidatus Cardinium and Wolbachia are vertically transmitted to progeny but rarely show co-speciation with the host. In sap-feeding insects, plant tissues have been proposed as alternative horizontal routes of interspecific transmission, but experimental evidence is limited. Here we report results from experiments that show that Cardinium is horizontally transmitted between different phloem sap-feeding insect species through plants. Quantitative PCR and in situ hybridization experiments indicated that the leafhopper Scaphoideus titanus releases Cardinium from its salivary glands during feeding on both artificial media and grapevine leaves. Successional time-course feeding experiments with S. titanus initially fed sugar solutions or small areas of grapevine leaves followed by feeding by the phytoplasma vector Macrosteles quadripunctulatus or the grapevine feeder Empoasca vitis revealed that the symbionts were transmitted to both species. Explaining interspecific horizontal transmission through plants improves our understanding of how symbionts spread, their lifestyle and the symbiont-host intermixed evolutionary pattern.

  7. Biogeography and molecular diversity of coral symbionts in the genus Symbiodinium around the Arabian Peninsula

    KAUST Repository

    Ziegler, Maren; Arif, Chatchanit; Burt, John A.; Dobretsov, Sergey; Roder, Cornelia; Lajeunesse, Todd C.; Voolstra, Christian R.

    2017-01-01

    Aim: Coral reefs rely on the symbiosis between scleractinian corals and intracellular, photosynthetic dinoflagellates of the genus Symbiodinium making the assessment of symbiont diversity critical to our understanding of ecological resilience of these ecosystems. This study characterizes Symbiodinium diversity around the Arabian Peninsula, which contains some of the most thermally diverse and understudied reefs on Earth. Location: Shallow water coral reefs throughout the Red Sea (RS), Sea of Oman (SO), and Persian/Arabian Gulf (PAG). Methods: Next-generation sequencing of the ITS2 marker gene was used to assess Symbiodinium community composition and diversity comprising 892 samples from 46 hard and soft coral genera. Results: Corals were associated with a large diversity of Symbiodinium, which usually consisted of one or two prevalent symbiont types and many types at low abundance. Symbiodinium communities were strongly structured according to geographical region and to a lesser extent by coral host identity. Overall symbiont communities were composed primarily of species from clade A and C in the RS, clade A, C, and D in the SO, and clade C and D in the PAG, representing a gradual shift from C- to D-dominated coral hosts. The analysis of symbiont diversity in an Operational Taxonomic Unit (OTU)-based framework allowed the identification of differences in symbiont taxon richness over geographical regions and host genera. Main conclusions: Our study represents a comprehensive overview over biogeography and molecular diversity of Symbiodinium in the Arabian Seas, where coral reefs thrive in one of the most extreme environmental settings on the planet. As such our data will serve as a baseline for further exploration into the effects of environmental change on host-symbiont pairings and the identification and ecological significance of Symbiodinium types from regions already experiencing 'Future Ocean' conditions.

  8. Aphid thermal tolerance is governed by a point mutation in bacterial symbionts.

    Directory of Open Access Journals (Sweden)

    Helen E Dunbar

    2007-05-01

    Full Text Available Symbiosis is a ubiquitous phenomenon generating biological complexity, affecting adaptation, and expanding ecological capabilities. However, symbionts, which can be subject to genetic limitations such as clonality and genomic degradation, also impose constraints on hosts. A model of obligate symbiosis is that between aphids and the bacterium Buchnera aphidicola, which supplies essential nutrients. We report a mutation in Buchnera of the aphid Acyrthosiphon pisum that recurs in laboratory lines and occurs in field populations. This single nucleotide deletion affects a homopolymeric run within the heat-shock transcriptional promoter for ibpA, encoding a small heat-shock protein. This Buchnera mutation virtually eliminates the transcriptional response of ibpA to heat stress and lowers its expression even at cool or moderate temperatures. Furthermore, this symbiont mutation dramatically affects host fitness in a manner dependent on thermal environment. Following a short heat exposure as juveniles, aphids bearing short-allele symbionts produced few or no progeny and contained almost no Buchnera, in contrast to aphids bearing symbionts without the deletion. Conversely, under constant cool conditions, aphids containing symbionts with the short allele reproduced earlier and maintained higher reproductive rates. The short allele has appreciable frequencies in field populations (up to 20%, further supporting the view that lowering of ibpA expression improves host fitness under some conditions. This recurring Buchnera mutation governs thermal tolerance of aphid hosts. Other cases in which symbiont microevolution has a major effect on host ecological tolerance are likely to be widespread because of the high mutation rates of symbiotic bacteria and their crucial roles in host metabolism and development.

  9. Biogeography and molecular diversity of coral symbionts in the genus Symbiodinium around the Arabian Peninsula

    KAUST Repository

    Ziegler, Maren

    2017-01-02

    Aim: Coral reefs rely on the symbiosis between scleractinian corals and intracellular, photosynthetic dinoflagellates of the genus Symbiodinium making the assessment of symbiont diversity critical to our understanding of ecological resilience of these ecosystems. This study characterizes Symbiodinium diversity around the Arabian Peninsula, which contains some of the most thermally diverse and understudied reefs on Earth. Location: Shallow water coral reefs throughout the Red Sea (RS), Sea of Oman (SO), and Persian/Arabian Gulf (PAG). Methods: Next-generation sequencing of the ITS2 marker gene was used to assess Symbiodinium community composition and diversity comprising 892 samples from 46 hard and soft coral genera. Results: Corals were associated with a large diversity of Symbiodinium, which usually consisted of one or two prevalent symbiont types and many types at low abundance. Symbiodinium communities were strongly structured according to geographical region and to a lesser extent by coral host identity. Overall symbiont communities were composed primarily of species from clade A and C in the RS, clade A, C, and D in the SO, and clade C and D in the PAG, representing a gradual shift from C- to D-dominated coral hosts. The analysis of symbiont diversity in an Operational Taxonomic Unit (OTU)-based framework allowed the identification of differences in symbiont taxon richness over geographical regions and host genera. Main conclusions: Our study represents a comprehensive overview over biogeography and molecular diversity of Symbiodinium in the Arabian Seas, where coral reefs thrive in one of the most extreme environmental settings on the planet. As such our data will serve as a baseline for further exploration into the effects of environmental change on host-symbiont pairings and the identification and ecological significance of Symbiodinium types from regions already experiencing \\'Future Ocean\\' conditions.

  10. Burkholderia Species Are the Most Common and Preferred Nodulating Symbionts of the Piptadenia Group (Tribe Mimoseae)

    Science.gov (United States)

    Bournaud, Caroline; de Faria, Sergio Miana; dos Santos, José Miguel Ferreira; Tisseyre, Pierre; Silva, Michele; Chaintreuil, Clémence; Gross, Eduardo; James, Euan K.; Prin, Yves; Moulin, Lionel

    2013-01-01

    Burkholderia legume symbionts (also called α-rhizobia) are ancient in origin and are the main nitrogen-fixing symbionts of species belonging to the large genus Mimosa in Brazil. We investigated the extent of the affinity between Burkholderia and species in the tribe Mimoseae by studying symbionts of the genera Piptadenia (P.), Parapiptadenia (Pp.), Pseudopiptadenia (Ps.), Pityrocarpa (Py.), Anadenanthera (A.) and Microlobius (Mi.), all of which are native to Brazil and are phylogenetically close to Mimosa, and which together with Mimosa comprise the “Piptadenia group”. We characterized 196 strains sampled from 18 species from 17 locations in Brazil using two neutral markers and two symbiotic genes in order to assess their species affiliations and the evolution of their symbiosis genes. We found that Burkholderia are common and highly diversified symbionts of species in the Piptadenia group, comprising nine Burkholderia species, of which three are new ones and one was never reported as symbiotic (B. phenoliruptrix). However, α-rhizobia were also detected and were occasionally dominant on a few species. A strong sampling site effect on the rhizobial nature of symbionts was detected, with the symbiont pattern of the same legume species changing drastically from location to location, even switching from β to α-rhizobia. Coinoculation assays showed a strong affinity of all the Piptadenia group species towards Burkholderia genotypes, with the exception of Mi. foetidus. Phylogenetic analyses of neutral and symbiotic markers showed that symbiosis genes in Burkholderia from the Piptadenia group have evolved mainly through vertical transfer, but also by horizontal transfer in two species. PMID:23691052

  11. Immunochemical localization of ribulose-1,5-bisphosphate carboxylase in the symbiont-containing gills of Solemya velum (Bivalvia: Mollusca).

    Science.gov (United States)

    Cavanaugh, C M; Abbott, M S; Veenhuis, M

    1988-10-01

    The distribution of the Calvin cycle enzyme ribulose-1,5-bisphosphate carboxylase (RbuP(2)Case; EC 4.1.1.39) was examined by using two immunological methods in tissues of Solemya velum, an Atlantic coast bivalve containing putative chemoautotrophic symbionts. Antibodies elicited by the purified large subunit of RbuP(2)Case from tobacco (Nicotiana tabacum) cross-reacted on immunoblots with a protein of similar molecular mass occurring in extracts of the symbiont-containing gill tissue of S. velum. No cross-reactivity was detected in symbiont-free tissue extracts. The antiserum also cross-reacted in immunoblots with proteins of Thiobacillus neapolitanus, a free-living sulfuroxidizing chemoautotroph whose RbuP(2)Case has been well characterized. In protein A-gold immunoelectron microscopy studies, this antiserum consistently labeled the symbionts but not surrounding host gill tissue, indicating that the symbionts are responsible for the RbuP(2)Case activity.

  12. Some effects of sulfite on photosynthesis in lichens

    Energy Technology Data Exchange (ETDEWEB)

    Hill, D J

    1974-01-01

    Details of the effect of sulfite H/sup 14/CO/sub 3//sup -/ fixation in the light were studied. The reduction of fixation by sulfite was rapid, taking place within 30 min of contact with the lichen. Parmelia physodes recovered in 24 h from almost total reduction of fixation caused by I h treatment with 0.4 mM sulfite but Usnea sp. did not. Studies with (/sup -35/S)sulfite indicated that sulfite was taken up nonlinearly with time and that it was bound to protein. Algae isolated from Usnea sp., Parmelia physodes and Lecanora conizaeoides were similar in their response to sulfite, although the intact lichen L. conizaeoides is known to be more resistant L. Conizaeoides did not seem to be resistant to sulfite by causing rapid oxidation of sulfite to sulfate. There was no marked effect of temperature on the concentration of sulfite required to reduce fixation in Usnea sp.

  13. Epiphytic lichens of apple orchards in Poland, Slovakia, and Italy

    Directory of Open Access Journals (Sweden)

    Daria Zarabska

    2013-12-01

    Full Text Available Following the study of epiphytic lichens in 30 apple orchards from Poland, Slovakia and Italy the list of 74 taxa was prepared. The most common are the meso- to xerophytic and heliophilous species. The highest number of taxa was observed in Slovak orchards. Moreover, lichens shared with at least one other country were also noted mainly in Slovakia. Bark of apple trees seems to create favourable habitats for Bacidia rubella, which together with Strangospora pinicola were valuable founds in Polish orchards. In Slovak orchards, special attention should be paid to Acrocordia gemmata, Melanelixia glabra and Usnea hirta. Among interesting records in Italian orchards, Phaeophyscia hispidula and Ph. kairamoi can be mentioned.

  14. Analysis of lichens for use in biomonitoring of environmental pollution

    International Nuclear Information System (INIS)

    Horimoto, Lidia K.; Saiki, Mitiko; Vasconcellos, Marina B.A.; Marcelli, Marcello P.

    2000-01-01

    This work presents the results of Al, As, Br, Ca, Cd, Cl, Co, Cs, Fe, K, Mg, Mn, Na, Rb, Se, Th, V and Zn obtained by instrumental neutron activation analysis in the analyses of epiphytic lichen samples collected in different sites of the States of Sao Paulo and Parana. These lichens were collected in the following sites: Cidade Universitaria, Campo Limpo Paulista, Sao Bernardo do Campo and Itanhaen situated in the State of Sao Paulo and one sample was from Vila Velha, Ponta Grossa of Parana State. The purpose of these analyses were to obtain preliminary information of air quality of these regions and also select a region of interest for biomonitoring studies. (author)

  15. Disease scoring systems for oral lichen planus; a critical appraisal

    Science.gov (United States)

    Wang, Jing

    2015-01-01

    The aim of the present study has been to critically review 22 disease scoring systems (DSSs) on oral lichen planus (OLP) that have been reported in the literature during the past decades. Although the presently available DSSs may all have some merit, particularly for research purposes, the diversity of both the objective and subjective parameters used in these systems and the lack of acceptance of one of these systems for uniform use, there is a need for an international, authorized consensus meeting on this subject. Because of the natural course of OLP characterized by remissions and exacerbations and also due to the varying distribution pattern and the varying clinical types, e.g. reticular and erosive, the relevance of a DSS based on morphologic parameters is somewhat questionable. Instead, one may consider to only look for a quality of life scoring system adapted for use in OLP patients. Key words:Oral lichen planus, disease scoring system, classification. PMID:25681372

  16. Effect of air pollution on epiphytic lichen vegetation and element contents of a lichen and pine needles at Valkeakoski, South Finland

    Energy Technology Data Exchange (ETDEWEB)

    Laaksovirta, K; Olkkonen, H

    1979-01-01

    The macrolichen vegetation on Pinus sylvestris L. and the contents of S, K, Ca, Ti, V, Fe and Zn in the lichen Hypogymnia physodes (L.) Nyl. and needles of Pinus sylvestris were investigated in relation to air pollution at 55 study stations in and around the industrial town of Valkeakoski, southern Finland. The air pollutants are emitted mainly by the wood pulp industry. The parameters of the lichen vegetation (occurrence of species, number of species, cover of the vegetation and the damage index) did not give a good picture of the distribution of air pollutants, because the environmental conditions were not exactly the same at the different study stations. The accumulation of the elements was more effective in the lichen than in pine needles and the lichen element contents agreed better with the pattern of the prevailing winds. The correlations between the contents of the different pollutant elements were also stronger in the lichen than in pine needles. The most reliable indices of pollutant substances originating from combustion of fuel oil and the wood pulp industry were the sulfur and vanadium contents of the lichen, while the calcium, titanium and iron concentrations of the lichen gave a good idea of the distribution of dust raised from the roads by traffic. 11 references, 10 figures, 4 tables.

  17. Global diversity of marine isopods (except Asellota and crustacean symbionts.

    Directory of Open Access Journals (Sweden)

    Gary C B Poore

    Full Text Available The crustacean order Isopoda (excluding Asellota, crustacean symbionts and freshwater taxa comprise 3154 described marine species in 379 genera in 37 families according to the WoRMS catalogue. The history of taxonomic discovery over the last two centuries is reviewed. Although a well defined order with the Peracarida, their relationship to other orders is not yet resolved but systematics of the major subordinal taxa is relatively well understood. Isopods range in size from less than 1 mm to Bathynomus giganteus at 365 mm long. They inhabit all marine habitats down to 7280 m depth but with few doubtful exceptions species have restricted biogeographic and bathymetric ranges. Four feeding categories are recognised as much on the basis of anecdotal evidence as hard data: detritus feeders and browsers, carnivores, parasites, and filter feeders. Notable among these are the Cymothooidea that range from predators and scavengers to external blood-sucking micropredators and parasites. Isopods brood 10-1600 eggs depending on individual species. Strong sexual dimorphism is characteristic of several families, notably in Gnathiidae where sessile males live with a harem of females while juvenile praniza stages are ectoparasites of fish. Protandry is known in Cymothoidae and protogyny in Anthuroidea. Some Paranthuridae are neotenous. About half of all coastal, shelf and upper bathyal species have been recorded in the MEOW temperate realms, 40% in tropical regions and the remainder in polar seas. The greatest concentration of temperate species is in Australasia; more have been recorded from temperate North Pacific than the North Atlantic. Of tropical regions, the Central Indo-Pacific is home to more species any other region. Isopods are decidedly asymmetrical latitudinally with 1.35 times as many species in temperate Southern Hemisphere than the temperate North Atlantic and northern Pacific, and almost four times as many Antarctic as Arctic species. More species

  18. Chemical Constituents of the Lichens Cladonia multiformis and Cryptothecia sp

    International Nuclear Information System (INIS)

    Hasliza Yusof; Husna Azahar; Laily Din; Nazlina Ibrahim

    2015-01-01

    Two depsides (atranorin 1 and evernic acid 4), an aromatic compound (methyl β-orcinolcarboxylate 2) and one cleavage product of depside (everninic acid 3) were isolated from two lichens, Cladonia multiformis (1 and 2) and Cryptothecia sp. (3 and 4). The identification of the four compounds was carried out by comparison of the recorded NMR data with that of the reported. Compounds 1 and 4 showed antibacterial activity against Bacillus subtilis and Enterobacter aerogenes. (author)

  19. Esophageal lichen planus: A rare and under-recognized disorder

    Directory of Open Access Journals (Sweden)

    Md Nadeem Parvez

    2016-01-01

    Full Text Available Lichen planus (LP is a chronic idiopathic disorder involving the skin and mucosal surfaces. Although oral mucosal involvement is common, esophageal LP (ELP is uncommon and also under-reported. Here, we present a case of ELP who was symptomatic with dysphagia for a year, but was untreated. Increasing awareness of this condition can help identify more cases and increase our understanding of this uncommon but interesting condition.

  20. Unilateral lichen planus pigmentosus mimicking acral lentiginous melanoma.

    Science.gov (United States)

    Bickle, Kelly; Smithberger, Erica; Lien, Mary H; Fenske, Neil Alan

    2010-07-01

    The authors report a case of a Latin American woman who developed progressive pigmentation primarily involving two digits of her right hand. She was scheduled for amputation based on a presumptive histologic diagnosis of melanoma with regression. Dermatology consultation with repeat biopsies disclosed a lichenoid tissue reaction with marked pigment incontinence and no evidence of melanoma. This report should prompt physicians to include lichen planus pigmentosus in the differential diagnosis of acral lentiginous melanoma.

  1. Checklist and Red List of lichens of the Czech Republic

    Czech Academy of Sciences Publication Activity Database

    Liška, Jiří; Palice, Zdeněk; Slavíková, Štěpánka

    2008-01-01

    Roč. 80, č. 2 (2008), s. 151-182 ISSN 0032-7786 R&D Projects: GA ČR(CZ) GA206/03/1214; GA AV ČR(CZ) IAA600050712 Institutional research plan: CEZ:AV0Z60050516 Keywords : biodiversity * lichenized fungi * threatened Subject RIV: EF - Botanics Impact factor: 2.396, year: 2008 http://www.ibot.cas.cz/preslia/P082Lis.pdf

  2. Specific Vicariance of Two Primeval Lowland Forest Lichen Indicators

    Science.gov (United States)

    Kubiak, Dariusz; Osyczka, Piotr

    2017-06-01

    To date, the lichens Chrysothrix candelaris and Varicellaria hemisphaerica have been classified as accurate primeval lowland forest indicators. Both inhabit particularly valuable remnants of oak-hornbeam forests in Europe, but tend toward a specific kind of vicariance on a local scale. The present study was undertaken to determine habitat factors responsible for this phenomenon and verify the indicative and conservation value of these lichens. The main spatial and climatic parameters that, along with forest structure, potentially affect their distribution patterns and abundance were analysed in four complexes with typical oak-hornbeam stands in NE Poland. Fifty plots of 400 m2 each were chosen for detailed examination of stand structure and epiphytic lichens directly associated with the indicators. The study showed that the localities of the two species barely overlap within the same forest community in a relatively small geographical area. The occurrence of Chrysothrix candelaris depends basically only on microhabitat space provided by old oaks and its role as an indicator of the ecological continuity of habitat is limited. Varicellaria hemisphaerica is not tree specific but a sufficiently high moisture of habitat is essential for the species and it requires forests with high proportion of deciduous trees in a wide landscape scale. Local landscape-level habitat continuity is more important for this species than the current age of forest stand. Regardless of the indicative value, localities of both lichens within oak-hornbeam forests deserve the special protection status since they form unique assemblages of exclusive epiphytes, including those with high conservation value.

  3. Needs" in Patients of Neurodermatitis Circumscripta (Lichen Simplex Chronicus

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    Bhushan Kumar

    1980-01-01

    Full Text Available Psychological needs of 20 adult male patients with neurodermatitis circumscripta(lichen simplex chronicus and 50 matched controls were studied using ten TAT cards.Need affiliation(100% need achievement (95%,need superiority (55% and need dominance(40% were the predominant needs.In contrast to the findings in other studies where aggressive needs were high in patients with atopic dermatitis our study showed that it was a prominent need in only one patient with neurodermatitis circumscripta.

  4. Cladonia metacorallifera, a lichen species new to the Eastern Carpathians

    Directory of Open Access Journals (Sweden)

    Piotr Osyczka

    2013-12-01

    Full Text Available A rare lichen Cladonia metacorallifera was found in the Bieszczady Mts. and this is the first report of the species from the Eastern Carpathians. In Poland, its occurrence is probably limited to small populations scattered in high mountain situations. The data of distribution of the species in Poland, ecological characterization of the new locality and some taxonomical remarks concerning the recorded specimen, as well as a photograph of its habit are provided.

  5. Lichen striatus occurring after a tetanus vaccine: A case report

    OpenAIRE

    Ayşegül Yalçınkaya İyidal; Kadir Balaban; Arzu Kılıç

    2017-01-01

    Lichen striatus (LS) is an uncommon, acquired, self-limiting, linear inflammatory dermatosis. The eruption typically presents as pink or tan papules along Blaschko’s lines. It usually occurs in children, rarely affects adults. The rashes usually suddenly emerge in a single extremity and may regress within a few months or years. The incidence is slightly higher among women. The etiology of LS is not exactly known, however, it is thought to be a T cell-mediated autoimmune reaction. Trauma, infe...

  6. Salivary oxidative status in patients with oral lichen planus.

    Science.gov (United States)

    Darczuk, D; Krzysciak, W; Vyhouskaya, P; Kesek, B; Galecka-Wanatowicz, D; Lipska, W; Kaczmarzyk, T; Gluch-Lutwin, M; Mordyl, B; Chomyszyn-Gajewska, M

    2016-12-01

    Reactive oxygen species (ROS) are involved in the pathogenesis of many inflammatory diseases, including oral lichen planus. Therefore, determining the salivary markers of oxidative stress is an excellent alternative approach to diagnosing oral cavity diseases. The objective of our study was to provide preliminary validation and determination of the salivary markers of oxidative stress in both patients with reticular and erosive forms of oral lichen planus as well as in healthy individuals without any oral lesions. In total, 62 patients with oral lichen planus (OLP) were enrolled in the study, including 31 with the reticular form of lichen planus (44.63 ± 11.05 years) and 31 with erosive forms (40.43 ± 10.05 years), who had never been treated for their disease. The control group comprised 30 individuals without any oral lesions (42.12 ± 12.22 years). We determined the saliva levels in glutathione (GSH), total antioxidant capacity (TAC), and thiobarbituric acid reactive substances (TBARS). The mean saliva levels of GSH and TAC were significantly lower (P < 0.01) in OLP patients compared to the control group. The mean levels of salivary TBARS were higher in both OLP groups (reticular and erosive) compared to the control group (P = 0.01). The lower saliva levels of GSH and TAC in patients with OLP indicate that free radicals and the resulting oxidative damage may play an important role in the pathogenesis of OLP lesions. In conclusion, monitoring the oxidant-antioxidant status of saliva may serve as an efficient and less intrusive marker for determining stages of disease development in patients with OLP.

  7. Changes in the lichen flora following air pollution

    Energy Technology Data Exchange (ETDEWEB)

    Skye, E; Hallberg, I

    1969-01-01

    The lichen flora on tree trunks around a shale oil works in southern Sweden has been analyzed with regard to composition and distribution on two different occasions, in 1951/1953 and in 1967/1969. Changes in the distribution have been observed and are regarded as being due to the increase of sulfur dioxide in the atmosphere which took place in the area up to 1966, and which resulted in the substrate becoming more and more acid. The changes consist partly of the continued disappearance from the investigated area of lichens which normally grow on moderately acid to nearly neutral substrate and partly in the new colonization of the investigated area by a group of species which normally grow on acid bark. After 1966 the biggest source of pollution was removed from the area and in the summer of 1967 some signs of recovery could be already observed with regard to certain species. This recovery took the form of strong lobe growth leading to a definite difference in appearance between the central and the peripheral parts of single lichens.

  8. Radiocesium in lichens and reindeer after the Chernobyl accident

    Directory of Open Access Journals (Sweden)

    K. Rissanen

    1990-09-01

    Full Text Available After the Chernobyl accident the sampling and measuring program of the Finnish Centre for Radiation and Nuclear Safety was intensified both for surveillance and research purposes. The deposition pattern of radionuclides was more complicated than from the global fallout after the nuclear weapons tests. The radioactive deposition was very unevenly distributed in Lapland, as also in the rest of Finland. Fortunately, the amounts of deposition in Lapland were only about one-tenth of the corresponding amount of deposition in southern Finland. In 1986-87 the mean concentration of Cs-137 in lichens and in reindeer meat increased to about the same level as in 1972-73 or to about 30 per cent of the maximum levels found in 1964-65 after the nuclear weapons tests. The activity concentrations in reindeer tissues vary according to season. In winter, reindeer eat considerable amounts of lichens with high radiocesium concentrations. In summer, lichens are replaced by other forage such as leaves from trees, green plants, etc. The ratio of Cs-137 concentration in reindeer meat between summer and winter is about 0.2. The mean concentration of Cs-137 in meat for consumption from the slaughtering period 1986-87 was 720 Bq/kg fresh weight. After that time concentrations started decreasing since no new fallout was deposited.

  9. Air pollution in relation to lichens and fungi

    Energy Technology Data Exchange (ETDEWEB)

    Saunders, P J.W.

    1970-01-01

    The ecology and survival of lichens and fungi can be drastically influenced by atmospheric pollution, particularly by SO/sub 2/. The extent of any damage will depend upon many factors of which the principal ones are type of pollutant, concentration and duration of exposure, inherent resistance of the organism affected and nature of substrate. Humidity, surface water, growth rate and shelter are also of considerable importance. SO/sub 2/ toxicity and pH effect are not independent factors because they are critical to each other. The evidence produced above would suggest that the phycobiont is the first component of lichens to be seriously affected and that the fungus in some way exposes the phycobiont to pollutant damage. Gilbert (1968) has concluded from the limited information available that the more sensitive species of lichens and bryophytes are considerably more susceptible to SO/sub 2/ pollution than are the fungi. It would appear, therefore, that photosynthetic ability is associated with sensitivity to SO/sub 2/ damage.

  10. ON THE PROBLEM OF THE TREATMENT OF GENITAL LICHEN PLANUS

    Directory of Open Access Journals (Sweden)

    Yu. A. Molochkova

    2016-01-01

    Full Text Available Lichen planus is a chronic inflammatory disease of the coated flat nonkeratinizing epithelium of the skin and mucous membranes. Still etiology of this disease is not completely clear. At the same time, many researchers have expressed their views in favor of the theory of occurrence of autoimmune planus. The emergence of this disease may also be associated with infectious diseases, trauma, hormonal disorders, and hereditary predisposition. Currently, standard treatment of lichen planus is topical application of corticosteroids. With the lack of effectiveness of the last clinicians suggest topical calcineurin inhibitors. That less, all treatments planus today are ineffective. Researchers continue to search for more effective treatments for this pathology. At this point in the treatment of various diseases is well proven photodynamic therapy. Given the high efficacy of photodynamic therapy in the treatment of basal cell carcinoma, actinic keratosis and various other skin diseases, clinicians began to fully explore the impact of the use of photodynamic therapy in the treatment of lichen planus.

  11. Líquen estriado no adulto Lichen striatus on adult

    Directory of Open Access Journals (Sweden)

    Leticia Fogagnolo

    2011-02-01

    Full Text Available Líquen estriado é uma erupção inflamatória incomum, de etiologia desconhecida. Raramente acomete adultos, e é caracterizada pelo surgimento abrupto de pápulas coalescentes, em arranjo linear, usualmente em extremidades. A histopatologia mostra reação liquenóide envolvendo folículos e glândulas. Ocasionalmente há sobreposição com líquen plano linear e "blaschkitis", seus principais diagnósticos diferenciais. Relata-se um caso de mulher adulta com pápulas eritematovioláceas em região cervical e hemiface direitas, cuja correlação clínico-histopatológica permitiu o diagnóstico de líquen estriado. Os achados atípicos e a dificuldade diagnóstica são discutidos.Lichen Striatus is an uncommon inflammatory skin eruption of unknown etiology. It rarely affects adults, and it is characterized by abrupt onset of coalescent papules, in a linear disposition, usually on the extremities. Histopathology shows lichenoid reaction involving follicles and glands. Occasionally, there is overlap with linear lichen planus and "blaschkitis", the main differential diagnoses. It is reported here the case of an adult woman with erythematous violaceous papules on the right side of the neck and face, diagnosed with lichen striatus by clinical and histopathological correlation. The atypical findings and the diagnostic difficulty are discussed.

  12. Facial follicular cysts: a case of lichen planus follicularis tumidus?

    Science.gov (United States)

    Jiménez-Gallo, David; Albarrán-Planelles, Cristina; Linares-Barrios, Mario; Martínez-Rodríguez, Alberto; Báez-Perea, José María; González-Fernández, Julio Abraham

    2013-09-01

    Lichen planus follicularis tumidus (LPFT) represents an uncommon variety of lichen planus (LP). Clinically, it presents with prominent purplish lesions or white-pigmented yellowish cysts and comedones. Histopathologically, it is similar to lichen planopilaris, and it is additionally characterized by follicles and cysts surrounded by a lichenoid lymphocytic infiltrate. The most common location is the retroauricular region, and it may be associated with other variants of LP. Herein, we describe the case of a 50-year-old woman with a history of lower limb hypertrophic LP who subsequently presented with multiple pink, tumid, pruritic plaques with white-yellow cysts and comedones extensively affecting the bilateral face. Histopathologic examination revealed a lichenoid infiltrate surrounding the follicles and cysts. We diagnosed LPFT and began treatment with topical corticosteroids, antihistamines, systemic corticosteroids and oral acitretin without improvement. Subsequently, the patient had an acceptable response to cyclosporine at doses of 5 mg/kg/day with remission of itching and tumidity but with residual cysts and comedones remaining. To date, the literature contains only 16 cases of LPFT. To our knowledge, this is the most severe case and is the only one with cessation of disease activity in response to cyclosporine. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  13. No evidence for Helicobacter pylori in oral lichen planus.

    Science.gov (United States)

    Hulimavu, Shwetha R; Mohanty, Leeky; Tondikulam, Narayan V; Shenoy, Sadhana; Jamadar, Saleha; Bhadranna, Abhishek

    2014-09-01

    Oral lichen planus is a T-cell-mediated mucosal disease of unknown etiology. Numerous predisposing factors have been put forward in the etiology of this disease. This includes stress, drugs, genetic susceptibility, certain viruses, and bacterial infections. Recently, there have been studies published on possible role of Helicobacter pylori infection in pathogenesis of mucocutaneous diseases including oral lichen planus (OLP). The aim of this study was to detect immunohistochemically the presence of Helicobacter pylori in oral lichen planus. Paraffin-embedded tissue blocks of 50 cases of OLP and 10 cases of normal buccal mucosal biopsies and 6 endoscopic biopsies of patients with peptic ulcer (control group) were sectioned and stained by hematoxylin and eosin. Serial sections of same were stained immunohistochemically using Anti-Helicobacter pylori antibody and observed under microscope for presence or absence of Helicobacter pylori. Except for the control group, none of the cases of OLP and normal buccal mucosal biopsies showed positivity for Helicobacter pylori. As we did not detect the presence of Helicobacter pylori in any of the OLP cases, we question the role of these organisms in the pathogenesis of OLP planus if any. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  14. Photodynamic Therapy in Treatment of Oral Lichen Planus

    Science.gov (United States)

    Mostafa, Diana; Tarakji, Bassel

    2015-01-01

    Oral lichen planus (OLP) is a relatively common chronic immunologic mucocutaneous disorder. Although there are many presenting treatments, some of them proved its failure. Recently, the use of photodynamic therapy (PDT) has been expanding due to its numerous advantages, as it is safe, convenient, and non-invasive and has toxic effect towards selective tissues. This article provides comprehensive review on OLP, its etiology, clinical features and recent non-pharmacological treatments. We also describe the topical PDT and its mechanisms. Our purpose was to evaluate the efficacy of PDT in treatment of OLP through collecting the data of the related clinical studies. We searched in PubMed website for the clinical studies that were reported from 2000 to 2014 using specific keywords: “photodynamic therapy” and “treatment of oral lichen planus”. Inclusion criteria were English publications only were concerned. In the selected studies of photodynamic treatment, adult patients (more than 20 years) were conducted and the OLP lesions were clinically and histologically confirmed. Exclusion criteria were classical and pharmacological treatments of OLP were excluded and also the using of PDT on skin lesions of lichen planus. We established five clinical studies in this review where all of them reported improvement and effectiveness of PDT in treatment of OLP lesions. The main outcome of comparing the related clinical studies is that the photodynamic is considered as a safe, effective and promising treatment modality for OLP. PMID:25883701

  15. Unexpected associated microalgal diversity in the lichen Ramalina farinacea is uncovered by pyrosequencing analyses.

    Directory of Open Access Journals (Sweden)

    Patricia Moya

    Full Text Available The current literature reveals that the intrathalline coexistence of multiple microalgal taxa in lichens is more common than previously thought, and additional complexity is supported by the coexistence of bacteria and basidiomycete yeasts in lichen thalli. This replaces the old paradigm that lichen symbiosis occurs between a fungus and a single photobiont. The lichen Ramalina farinacea has proven to be a suitable model to study the multiplicity of microalgae in lichen thalli due to the constant coexistence of Trebouxia sp. TR9 and T. jamesii in long-distance populations. To date, studies involving phycobiont diversity within entire thalli are based on Sanger sequencing, but this method seems to underestimate the diversity. Here, we aim to analyze both the microalgal diversity and its community structure in a single thallus of the lichen R. farinacea by applying a 454 pyrosequencing approach coupled with a careful ad hoc-performed protocol for lichen sample processing prior to DNA extraction. To ascertain the reliability of the pyrosequencing results and the applied bioinformatics pipeline results, the thalli were divided into three sections (apical, middle and basal zones, and a mock community sample was used. The developed methodology allowed 40448 filtered algal reads to be obtained from a single lichen thallus, which encompassed 31 OTUs representative of different microalgae genera. In addition to corroborating the coexistence of the two Trebouxia sp. TR9 and T. jamesii taxa in the same thallus, this study showed a much higher microalgal diversity associated with the lichen. Along the thallus ramifications, we also detected variations in phycobiont distribution that might correlate with different microenvironmental conditions. These results highlight R. farinacea as a suitable material for studying microalgal diversity and further strengthen the concept of lichens as multispecies microecosystems. Future analyses will be relevant to

  16. Richness of lichen species, especially of threatened ones, is promoted by management methods furthering stand continuity.

    Directory of Open Access Journals (Sweden)

    Steffen Boch

    Full Text Available Lichens are a key component of forest biodiversity. However, a comprehensive study analyzing lichen species richness in relation to several management types, extending over different regions and forest stages and including information on site conditions is missing for temperate European forests. In three German regions (Schwäbische Alb, Hainich-Dün, Schorfheide-Chorin, the so-called Biodiversity Exploratories, we studied lichen species richness in 631 forest plots of 400 m(2 comprising different management types (unmanaged, selection cutting, deciduous and coniferous age-class forests resulting from clear cutting or shelterwood logging, various stand ages, and site conditions, typical for large parts of temperate Europe. We analyzed how lichen species richness responds to management and habitat variables (standing biomass, cover of deadwood, cover of rocks. We found strong regional differences with highest lichen species richness in the Schwäbische Alb, probably driven by regional differences in former air pollution, and in precipitation and habitat variables. Overall, unmanaged forests harbored 22% more threatened lichen species than managed age-class forests. In general, total, corticolous, and threatened lichen species richness did not differ among management types of deciduous forests. However, in the Schwäbische-Alb region, deciduous forests had 61% more lichen species than coniferous forests and they had 279% more threatened and 76% more corticolous lichen species. Old deciduous age classes were richer in corticolous lichen species than young ones, while old coniferous age-classes were poorer than young ones. Overall, our findings highlight the importance of stand continuity for conservation. To increase total and threatened lichen species richness we suggest (1 conserving unmanaged forests, (2 promoting silvicultural methods assuring stand continuity, (3 conserving old trees in managed forests, (4 promoting stands of native deciduous

  17. The Conjugates of Phenolic Acids in Lichens of the Order Lecanorales

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    T. N. NIKOLAEVA

    2014-06-01

    Full Text Available Lichens are symbiotic associations of a fungus (usually an ascomycete and a photobiont, which may be an alga and/or a cyanobacterium. Lichens dominate on about 6–8% of land surface, mainly in the habitats with severe climatic conditions. Lichenized fungi are among the pioneer vegetation on bare rock or soil. Mat-forming species contribute substantially to the soil cover in tundras and high mountain elevations. Lichens are rich in water-soluble compounds which can be leached-out the lichen thalli with atmospheric depositions. We have recently described the occurrence of water-soluble phenolics in lichens (Zagoskina et al 2013. These compounds can play important role in the ecosystem functioning and primary soil formation (weathering, humification. The aim of this work was to study qualitative composition of water-soluble phenolics in the lichen species widespread in the soil cover of tundra zone. The air-dried thalli of Alectoria ochroleuca, Cetraria islandica, C.nigricans, C.nivalis, Cladonia arbuscula and C.stellaris were homogenized to powder and used for the study. Lichens were collected in Khibiny mountains, Kola Peninsula in August 2013. Phenolic compounds were extracted by distilled water (1h, 30C and analyzed by TLC before and after the acid hydrolysis. It was found that all the lichens under the study contained the conjugates of phenol carboxylic acids. We have identified that non-phenolic part in some of these conjugates was represented by sugars and amino acids. The TLC of the hydrolizates of water extracts revealed occurrence of p-oxybenzoic acid in all of the species studied. The lichens Cetraria islandica, С.nigricans and Cladonia stellaris contained also vanillic acid. These phenolic acids are widespread in plant kingdom and are known as products of lignin decomposition in higher plants. The physiological role of water-soluble phenolics in lichens as well as their environmental role are need to be understood in future studies.

  18. Richness of Lichen Species, Especially of Threatened Ones, Is Promoted by Management Methods Furthering Stand Continuity

    Science.gov (United States)

    Boch, Steffen; Prati, Daniel; Hessenmöller, Dominik; Schulze, Ernst-Detlef; Fischer, Markus

    2013-01-01

    Lichens are a key component of forest biodiversity. However, a comprehensive study analyzing lichen species richness in relation to several management types, extending over different regions and forest stages and including information on site conditions is missing for temperate European forests. In three German regions (Schwäbische Alb, Hainich-Dün, Schorfheide-Chorin), the so-called Biodiversity Exploratories, we studied lichen species richness in 631 forest plots of 400 m2 comprising different management types (unmanaged, selection cutting, deciduous and coniferous age-class forests resulting from clear cutting or shelterwood logging), various stand ages, and site conditions, typical for large parts of temperate Europe. We analyzed how lichen species richness responds to management and habitat variables (standing biomass, cover of deadwood, cover of rocks). We found strong regional differences with highest lichen species richness in the Schwäbische Alb, probably driven by regional differences in former air pollution, and in precipitation and habitat variables. Overall, unmanaged forests harbored 22% more threatened lichen species than managed age-class forests. In general, total, corticolous, and threatened lichen species richness did not differ among management types of deciduous forests. However, in the Schwäbische-Alb region, deciduous forests had 61% more lichen species than coniferous forests and they had 279% more threatened and 76% more corticolous lichen species. Old deciduous age classes were richer in corticolous lichen species than young ones, while old coniferous age-classes were poorer than young ones. Overall, our findings highlight the importance of stand continuity for conservation. To increase total and threatened lichen species richness we suggest (1) conserving unmanaged forests, (2) promoting silvicultural methods assuring stand continuity, (3) conserving old trees in managed forests, (4) promoting stands of native deciduous tree species

  19. Increased salivary aldehyde dehydrogenase 1 in non-reticular oral lichen planus.

    Science.gov (United States)

    Mansourian, Arash; Shanbehzadeh, Najmeh; Kia, Seyed Javad; Moosavi, Mahdieh-Sadat

    2017-01-01

    Oral lichen planus is a potentially malignant disorder. One of the malignant transformation markers is cancer stem cells. One of the proposed marker for the detection of cancer stem cells's in head and neck cancer is aldehyde dehydrogenase. Recently it is shown that aldehyde dehydrogenase 1 expression in tissue samples is associated with oral lichen planus malignant transformation. This study evaluates salivary aldehyde dehydrogenase 1 in oral lichen planus. Thirty patients and 30 age and sex-matched healthy volunteers were recruited. Oral lichen planus was diagnosed based on the modified World Health Organization criteria. Subjects in the case group were divided into reticular and non-reticular forms. Unstimulated salivary samples were collected at 10-12 AM. Saliva concentrations of aldehyde dehydrogenase 1 were measured by ELISA. The differences between aldehyde dehydrogenase levels in the oral lichen planus group compared with the control group were not significant but aldehyde dehydrogenase in non-reticular oral lichen planus was significantly higher than that of the reticular form. This is a cross-sectional study, thus longitudinal studies in oral lichen planus may present similar or different results. The mechanism of malignant transformation in oral lichen planus is not defined. Previous analyses revealed that the aldehyde dehydrogenase 1 expression is significantly correlated with increased risk of transformation. This finding is consistent with our results because in the erosive and ulcerative forms of oral lichen planus, which have an increased risk of transformation, salivary aldehyde dehydrogenase 1 was overexpressed. A higher salivary aldehyde dehydrogenase level in non-reticular oral lichen planus can be a defensive mechanism against higher oxidative stress in these groups. Aldehyde dehydrogenase may be one of the malignant transformation markers in oral lichen planus. Further studies are needed for introducing aldehyde dehydrogenase as a prognostic

  20. Increased salivary aldehyde dehydrogenase 1 in non-reticular oral lichen planus*

    Science.gov (United States)

    Mansourian, Arash; Shanbehzadeh, Najmeh; Kia, Seyed Javad; Moosavi, Mahdieh-Sadat

    2017-01-01

    Background Oral lichen planus is a potentially malignant disorder. One of the malignant transformation markers is cancer stem cells. One of the proposed marker for the detection of cancer stem cells's in head and neck cancer is aldehyde dehydrogenase. Recently it is shown that aldehyde dehydrogenase 1 expression in tissue samples is associated with oral lichen planus malignant transformation. Objective This study evaluates salivary aldehyde dehydrogenase 1 in oral lichen planus. Method Thirty patients and 30 age and sex-matched healthy volunteers were recruited. Oral lichen planus was diagnosed based on the modified World Health Organization criteria. Subjects in the case group were divided into reticular and non-reticular forms. Unstimulated salivary samples were collected at 10-12 AM. Saliva concentrations of aldehyde dehydrogenase 1 were measured by ELISA. Results The differences between aldehyde dehydrogenase levels in the oral lichen planus group compared with the control group were not significant but aldehyde dehydrogenase in non-reticular oral lichen planus was significantly higher than that of the reticular form. Limitations of the study This is a cross-sectional study, thus longitudinal studies in oral lichen planus may present similar or different results. Conclusions The mechanism of malignant transformation in oral lichen planus is not defined. Previous analyses revealed that the aldehyde dehydrogenase 1 expression is significantly correlated with increased risk of transformation. This finding is consistent with our results because in the erosive and ulcerative forms of oral lichen planus, which have an increased risk of transformation, salivary aldehyde dehydrogenase 1 was overexpressed. A higher salivary aldehyde dehydrogenase level in non-reticular oral lichen planus can be a defensive mechanism against higher oxidative stress in these groups. Aldehyde dehydrogenase may be one of the malignant transformation markers in oral lichen planus. Further