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Sample records for lichen thallus structure

  1. 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.

  2. ANTHRAQUINONE FROM THALLUS OF LICHEN Ramalina javanica Nyl

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    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

  3. Variations of sulfur isotope ratios in a single lichen thallus: A potential historical archive for sulfur pollution

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    Yun, Misuk, E-mail: yun@cc.umanitoba.c [Department of Earth Sciences and Environmental Science Program, Memorial University, St. John' s, NL, A1B 3X5 (Canada); Wadleigh, Moire A. [Department of Earth Sciences and Environmental Science Program, Memorial University, St. John' s, NL, A1B 3X5 (Canada); Mayer, Bernhard [Department of Geoscience, University of Calgary, 2500 University Dr. NW, Calgary, AB, T2N 1N4 (Canada)

    2010-12-15

    Utilizing the analytical capability to measure S isotope ratios of small quantities of S in biological material without any chemical pretreatment, the variation of {delta}{sup 34}S within a lichen thallus was investigated using old and young segments of fruticose lichen thalli (Alectoria sarmentosa) from an oil refinery area in Come-By-Chance and two coastal areas, Newfoundland, Canada. Old segments of lichen samples from the oil refinery area showed significantly higher {delta}{sup 34}S values (1.0-2.5 per mille) than their corresponding young segments. Lichen samples from two coastal areas showed no noticeable differences in {delta}{sup 34}S values between old and young segments. These results demonstrate that lichen thalli record temporal changes in the isotopic composition of atmospheric S and hence constitute a historical archive of atmospheric S pollution. - Lichen thalli record temporal changes in the isotopic composition of atmospheric S and hence constitute a suitable historical archive for biomonitoring.

  4. Variations of sulfur isotope ratios in a single lichen thallus: A potential historical archive for sulfur pollution

    International Nuclear Information System (INIS)

    Yun, Misuk; Wadleigh, Moire A.; Mayer, Bernhard

    2010-01-01

    Utilizing the analytical capability to measure S isotope ratios of small quantities of S in biological material without any chemical pretreatment, the variation of δ 34 S within a lichen thallus was investigated using old and young segments of fruticose lichen thalli (Alectoria sarmentosa) from an oil refinery area in Come-By-Chance and two coastal areas, Newfoundland, Canada. Old segments of lichen samples from the oil refinery area showed significantly higher δ 34 S values (1.0-2.5 per mille ) than their corresponding young segments. Lichen samples from two coastal areas showed no noticeable differences in δ 34 S values between old and young segments. These results demonstrate that lichen thalli record temporal changes in the isotopic composition of atmospheric S and hence constitute a historical archive of atmospheric S pollution. - Lichen thalli record temporal changes in the isotopic composition of atmospheric S and hence constitute a suitable historical archive for biomonitoring.

  5. Copper localization, elemental content, and thallus colour in the copper hyperaccumulator lichen Lecanora sierrae from California

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    Purvis, O.W.; Bennett, J.P.; Spratt, J.

    2011-01-01

    An unusual dark blue-green lichen, Lecanora sierrae, was discovered over 30 years ago by Czehura near copper mines in the Lights Creek District, Plumas County, Northern California. Using atomic absorption spectroscopy, Czehura found that dark green lichen samples from Warren Canyon contained 4% Cu in ash and suggested that its colour was due to copper accumulation in the cortex. The present study addressed the hypothesis that the green colour in similar material we sampled from Warren Canyon in 2008, is caused by copper localization in the thallus. Optical microscopy and electron microprobe analysis of specimens of L. sierrae confirmed that copper localization took place in the cortex. Elemental analyses of L. sierrae and three other species from the same localities showed high enrichments of copper and selenium, suggesting that copper selenates or selenites might occur in these lichens and be responsible for the unusual colour. Copyright ?? 2011 British Lichen Society.

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

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    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.

  7. Copper localization, elemental content, and thallus colour in the copper hyperaccumulator lichen Lecanora sierra from California

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    Purvis, O.W.; Bennett, J.P.; Spratt, J.

    2011-01-01

    An unusual dark blue-green lichen, Lecanora sierrae, was discovered over 30 years ago by Czehura near copper mines in the Lights Creek District, Plumas County, Northern California. Using atomic absorption spectroscopy, Czehura found that dark green lichen samples from Warren Canyon contained 4% Cu in ash and suggested that its colour was due to copper accumulation in the cortex. The present study addressed the hypothesis that the green colour in similar material we sampled from Warren Canyon in 2008, is caused by copper localization in the thallus. Optical microscopy and electron microprobe analysis of specimens of L. sierrae confirmed that copper localization took place in the cortex. Elemental analyses of L. sierrae and three other species from the same localities showed high enrichments of copper and selenium, suggesting that copper selenates or selenites might occur in these lichens and be responsible for the unusual colour.

  8. 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.

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    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.

  9. Lichen specific thallus mass and secondary compounds change across a retrogressive fire-driven chronosequence.

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    Asplund, Johan; Sandling, Aron; Wardle, David A

    2012-01-01

    In the long-term absence of major disturbances ecosystems enter a state of retrogression, which involves declining soil fertility and consequently a reduction in decomposition rates. Recent studies have looked at how plant traits such as specific leaf mass and amounts of secondary compounds respond to declining soil fertility during retrogression, but there are no comparable studies for lichen traits despite increasing recognition of the role that lichens can play in ecosystem processes. We studied a group of 30 forested islands in northern Sweden differing greatly in fire history, and collectively representing a retrogressive chronosequence, spanning 5000 years. We used this system to explore how specific thallus mass (STM) and carbon based secondary compounds (CBSCs) change in three common epiphytic lichen species (Hypogymnia phsyodes, Melanohalea olivacea and Parmelia sulcata) as soil fertility declines during this retrogression. We found that STMs of lichens increased sharply during retrogression, and for all species soil N to P ratio (which increased during retrogression) was a strong predictor of STM. When expressed per unit area, medullary CBSCs in all species and cortical CBSCs in P. sulcata increased during retrogression. Meanwhile, when expressed per unit mass, only cortical CBSCs in H. physodes responded to retrogression, and in the opposite direction. Given that lichen functional traits are likely to be important in driving ecological processes that drive nutrient and carbon cycling in the way that plant functional traits are, the changes that they undergo during retrogression could potentially be significant for the functioning of the ecosystem.

  10. Exploring symbiont management in lichens.

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    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.

  11. Microbiome change by symbiotic invasion in lichens

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    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

  12. 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

  13. Unexpected associated microalgal diversity in the lichen Ramalina farinacea is uncovered by pyrosequencing analyses.

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    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

  14. Surface Hydrophobicity Causes SO2 Tolerance in Lichens

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    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

  15. 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.

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

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    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.

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

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    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

  18. Accumulation of /sup 90/Sr and /sup 137/Cs in lichens under experimental conditions

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    Nifontova, M G [AN SSSR, Sverdlovsk. Inst. Ehkologii Rastenij i Zhivotnykh

    1976-01-01

    A study was made of the accumulation from aqueous media of two long-lived radionuclides---/sup 90/Sr and /sup 137/Cs---by the thalluses of eight species of lichens of different ecological and morphological groups (soil bushy lichens and foliated forms; epiphytic bushy and foliated; epilytic foliated). Fhe efficiency of accumulation of radionuclides by the thalluses was determined from the accumulation coefficient (KN) (koehfitsient nakopleniya). There was a distinct difference in the radionuclide accumulation by the different species of lichens. Based on their radionuclide accumulation, the lichens were divided into three groups. It was shown that not only do different species of lichens differ in their accumulation of the same radionuclide, but also the thalluses of the same species are not the same in the sorption of different radionuclides. However, on an average, the bushy forms of lichens accumulated /sup 90/Sr and /sup 137/Cs more than the leafy types. The lichens studied may be arrangd according to their accumulation of /sup 90/Sr: epiphytes > soil types > epilytes, or their /sup 137/Cs accumulation: soil types > epilytes > epiphytes.

  19. Estimation of the proportion of some elements and their distribution on a surface of thallus of lichenized fungus Xanthoria parietina (L. Th. Fr. using sample-nondestructive μ-XRF spectrometer M4 Tornado

    Directory of Open Access Journals (Sweden)

    Biazrov Lev Georgievich

    2013-10-01

    Full Text Available The composition of 19 elements - Al, Si, P, S, Cl, K, Ca, Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Sr, Ba, Pb - were compared in the peripheral (younger and central (older parts of the upper surface of the epiphytic lichen Xanthoria parietina thallus from the bark of Sorbus aucuparia in Moscow city using sample-nondestructive μ-XRF spectrometer. This species is often used in biomonitoring of air quality. The results showed that the elements content was highly variable. Mean values of atomic percent of Fe, Co, Zn, and Pb were statistically higher in the central part of the upper surface, while P, S, Cl, K, Ca, and Mn were higher in the peripheral part. Differences between other elements were not statistically valid, but there is a trend to greater maintenance of the majority of the elements on the surface of the central part of the thallus. Mapping the distribution of some elements on the part of the thallus surface is presented.

  20. 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

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

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    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)

  2. 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)

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

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    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. 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.

  5. 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.

  6. INFLUENCE OF MINING AND METAL INDUSTRY ON PHYSCIA LICHENS

    Directory of Open Access Journals (Sweden)

    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.

  7. Lichens as indicators of air pollution in a steal producing town in South Wales

    Energy Technology Data Exchange (ETDEWEB)

    Pratt, F B

    1970-01-01

    The lichen flora of a given region depends upon a multiplicity of factors. Some factors act directly or indirectly upon the lichen thallus; in addition the lichen thallus is capable, to some extent at least, of exerting a modifying influence upon the macro- and micro-environment. The polluted centre of Port Talbot, a steel town, has a restricted number of Crustose and rather Depauperate species. This lichen desert is quite small possibly because either (a) the atmosphere is not heavily polluted, or (b) there is a rapid dilution of pollutants. With distance away from Port Talbot there is an increase in the number of lichen species and a change in the proportion of the various growth forms. Abutting the lichen desert is a zone in which parmelia sulcata, P. saxatilis, Cladonia coniocraea, and C. fimbriata are the most widely represented species. This is followed by a further zone dominated by USNEA comosa, U. florida, Cetraria glauca, and Cladonia impexa in particular. It must be noted that these zones are not clearly defined; there is a gradation in growth forms and a gradual change in the abundance of various species.

  8. 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.

  9. 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.

  10. 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.

  11. Photosynthetic recovery and acclimation to excess light intensity in the rehydrated lichen soil crusts.

    Directory of Open Access Journals (Sweden)

    Li Wu

    Full Text Available As an important successional stage and main type of biological soil crusts (BSCs in Shapotou region of China (southeastern edge of Tengger Desert, lichen soil crusts (LSCs often suffer from many stresses, such as desiccation and excess light intensity. In this study, the chlorophyll fluorescence and CO2 exchange in the rehydrated LSCs were detected under a series of photosynthetically active radiation (PAR gradients to study the photosynthetic acclimation of LSCs. The results showed that although desiccation leaded to the loss of photosynthetic activity in LSCs, the fluorescence parameters including Fo, Fv and Fv/Fm of LSCs could be well recovered after rehydration. After the recovery of photosynthetic activity, the effective photosynthetic efficiency ΦPSII detected by Imaging PAM had declined to nearly 0 within both the lichen thallus upper and lower layers when the PAR increased to 200 μE m-2 s-1, however the net photosynthesis detected by the CO2 gas analyzer in the LSCs still appeared when the PAR increased to 1000 μE m-2 s-1. Our results indicate that LSCs acclimating to high PAR, on the one hand is ascribed to the special structure in crust lichens, making the incident light into the lichen thallus be weakened; on the other hand the massive accumulation of photosynthetic pigments in LSCs also provides a protective barrier for the photosynthetic organisms against radiation damage. Furthermore, the excessive light energy absorbed by crust lichens is also possibly dissipated by the increasing non-photochemical quenching, therefore to some extent providing some protection for LSCs.

  12. Assessment of air quality in Mangabeiras' Park, Belo Horizonte, Brazil, using epiphytic lichens as biomonitor

    International Nuclear Information System (INIS)

    Viana, Camila de O.; Menezes, Maria Angela de B.C.; Maia, Elene C.P.

    2009-01-01

    Biomonitoring has been used as an alternative method to study the air pollution in several countries. The lichen, or lichenized fungi, is one of the most efficient on air pollution biomonitoring among the biomonitors. However, in Brazil, systematic use of lichens as biomonitors of environmental pollution is quite rare. In order to make an assessment of the air quality of the Mangabeiras' Park, this study was conducted by measuring the concentration of elements accumulated in the lichen thallus. This park, located in Belo Horizonte (Minas Gerais, Brazil), is the greatest green area in the city, and an apparent region of non polluted air. During the development of the study, epiphytic lichens of several species were collected using a steel stainless knife, taking samples of similar sizes from 1.5 m from the soil. The lichens selection was based on morphological similarities, such as color and type of the thallus. The elemental concentration determination was carried out applying the neutron activation technique, k 0 -standardization method, using the TRIGA Mark I IPR-R1 research reactor located at CDTN/CNEN. The lichen samples presented expressive concentrations of Ba, Fe, K, Na and Zn. However, the presence of other characteristic soil elements from the region, such as As, Th and U, suggests the influence of the mining activity area, located in the surroundings. (author)

  13. Lichens as indicators of air pollution in a steel producing town in South Wales. [Cladonia, Parmelia, Usnea, Cetraria

    Energy Technology Data Exchange (ETDEWEB)

    Pyatt, F B

    1970-01-01

    The lichen flora of a given region depends upon a multiplicity of factors. Some factors act directly or indirectly upon the lichen thallus; in addition the lichen thallus is capable, to some extent at least, of exerting a modifying influence upon the macro- and micro-environment. The polluted centre of Port Talbot, a steel town, has a restricted number of crustose and rather depauperate species. This lichen desert is quite small possibly because either (a) the atmosphere is not heavily polluted, or (b) there is a rapid dilution of pollutants. With distance away from Port Talbot there is an increase in the number of lichen species and a change in the proportion of the various growth forms. Abutting the lichen desert is a zone in which Parmelia sulcata, P. saxatilis, Cladonia coniocraea, and C. fimbriata are the most widely represented species. This is followed by a further zone dominated by Usnea comosa, U. florida, Cetraria glauca, and Cladonia impexa in particular. It must be noted that these zones are not clearly defined; there is a gradation in growth forms and a gradual change in the abundance of various species.

  14. Characterization of the diversity of mycosporine-like amino acids in lichens from high altitude region of Himalaya.

    Science.gov (United States)

    Shukla, Vertika; Kumari, Rupender; Patel, Davendra K; Upreti, Dalip K

    2016-01-01

    Lichens are tolerant to a number of environmental variables including high-intensity solar radiations, which is mainly due to the presence of chemical substances in the thallus. Especially, cyanobacterial lichens synthesize a unique class of chemical substances known as mycosporine-like amino acids (MAAs) the primary characteristic of which is strong ultraviolet (UV) absorption between 300 and 360 nm. In view of its UV-protecting potential, the applicability of mass spectral fragmentation using electrospray ionization tandem mass spectrometric analysis for the characterization of MAAs in lichen samples was explored. MAA compounds were characterized in four cyanobacteria-containing lichen species belonging to genus Peltigera, Stereocaulon and Lobaria. Among them, Peltigera and Lobaria are true cyanobacteria containing lichens (cyanolichens) while Stereocaulon is a tripartite lichen, as it contains both green algae (in the thallus) and cyanobacteria (in the cephalodia), collected from higher altitudes of Himalaya (Tungnath-Chopta in Garhwal Himalaya, 3432 m) from an exposed locality experiencing high light intensity. Mass spectral data of distinctive fragmentation pattern revealed that all the four species have good diversity of MAA compounds, especially Lobaria retigera was found to be enriched with highest diversity of oxo and imino MAAs. Overall, different numbers of oxo and imino MAA compounds were detected in the remaining lichen species. Good diversity of imino MAAs has ecological significance which is required to be investigated further. Moreover, the impressive diversity characterized in each lichen species suggests that lichens should be thoroughly studied for their MAAs contents.

  15. 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

  16. Influence of a range of extreme environmental factors on tripartite lichen Peltigera aphthosa thallus viability

    Science.gov (United States)

    Irina, Insarova; Dyakov, Max; Ptushenko, Vasiliy; Shtaer, Oksana

    Lichens are symbiotic organisms consisting of at least two genetic different partners: a heterotrophic fungus (mycobiont) and a phototrophic alga or cyanobacterium (photobiont). Lichens are ubiquitous at global scale. These symbiotic organisms represent the dominant type of “vegetation” at 8 - 10% of land (Larson, 1987). Abiotic stress’ resistance is notable for lichens among all eukaryotes. Lichens are often called “extremophiles” for their ability to acclimate the most severe environmental conditions. These features allow regarding lichens as a group of organisms which is potentially able to keep viability under open space conditions and to survive within Mars-like atmosphere types. The research presented was carried out in the network of spacecraft Bion-1 experiments involving the investigation of physiological and ultrastructural changes in biological objects survivable under open space conditions. Similar researches were already conducted on bipartite lichen species. The most attention was paid to the influence of UV and other space radiation types on lichen viability in those works. Thus we have taken tripartite lichen Peltigera aphthosa as a main research object and temperature fluctuations from extremely high to extremely low values in accordance to solar and umbral orbit sides - for the main extreme environmental factors. These factors were the less studied in previous works. During the research the influence of incubation under anaerobic conditions, multi-time effects of high and low temperatures and their interchange on respiratory metabolism, photosynthetic apparatus condition and the ultrastructure of P. aphthosa thalli was assessed. The data obtained demonstrate that activity either mycobiont or photobiont in tripartite lichen Peltigera aphthosa keep near unchanged under influence of all stress factors explored on dry thalli.

  17. Terricolous alpine lichens are sensitive to both load and concentration of applied nitrogen and have potential as bioindicators of nitrogen deposition

    International Nuclear Information System (INIS)

    Britton, Andrea J.; Fisher, Julia M.

    2010-01-01

    The influence of applied nitrogen (N) concentration and load on thallus chemistry and growth of five terricolous alpine lichen species was investigated in a three-month N addition study. Thallus N content was influenced by both concentration and load; but the relative importance of these parameters varied between species. Growth was most affected by concentration. Thresholds for effects observed in this study support a low critical load for terricolous lichen communities ( -1 y -1 ) and suggest that concentrations of N currently encountered in UK cloudwater may have detrimental effects on the growth of sensitive species. The significance of N concentration effects on sensitive species also highlights the need to avoid artificially high concentrations when designing N addition experiments. Given the sensitivity of some species to extremely low loads and concentrations of N we suggest that terricolous lichens have potential as indicators of deposition and impact in northern and alpine ecosystems. - Terricolous lichen species' N content responds to both applied N concentration and load while applied N concentration has greatest effects on growth.

  18. Terricolous alpine lichens are sensitive to both load and concentration of applied nitrogen and have potential as bioindicators of nitrogen deposition

    Energy Technology Data Exchange (ETDEWEB)

    Britton, Andrea J., E-mail: a.britton@macaulay.ac.u [Macaulay Land Use Research Institute, Craigiebuckler, Aberdeen AB15 8QH (United Kingdom); Fisher, Julia M. [Macaulay Land Use Research Institute, Craigiebuckler, Aberdeen AB15 8QH (United Kingdom)

    2010-05-15

    The influence of applied nitrogen (N) concentration and load on thallus chemistry and growth of five terricolous alpine lichen species was investigated in a three-month N addition study. Thallus N content was influenced by both concentration and load; but the relative importance of these parameters varied between species. Growth was most affected by concentration. Thresholds for effects observed in this study support a low critical load for terricolous lichen communities (<7.5 kg N ha{sup -1} y{sup -1}) and suggest that concentrations of N currently encountered in UK cloudwater may have detrimental effects on the growth of sensitive species. The significance of N concentration effects on sensitive species also highlights the need to avoid artificially high concentrations when designing N addition experiments. Given the sensitivity of some species to extremely low loads and concentrations of N we suggest that terricolous lichens have potential as indicators of deposition and impact in northern and alpine ecosystems. - Terricolous lichen species' N content responds to both applied N concentration and load while applied N concentration has greatest effects on growth.

  19. 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.

  20. Level of zinc in the Belgian calamine-bearing lichens: Stereocaulon nanodes Tuck f tyroliense (nyl. ) M. Lamb

    Energy Technology Data Exchange (ETDEWEB)

    Maquinay, A; Lamb, I M; Lambinon, J; Ramaut, J L

    1961-01-01

    It has been shown that Stereocaulon nanodes, a lichen species native to Belgian calamine-bearing soils takes up zinc and in some cases accumulates it in the thallus. This lichen, growing on a substrate slag with 700 p.p.m. of zinc may contain up to 3300 p.p.m. This abnormally high content as compared with the usual plant tolerance for this element does not seem to disturb its metabolism. 3 references, 4 tables.

  1. Exploring functional contexts of symbiotic sustain within lichen-associated bacteria by comparative omics

    Science.gov (United States)

    Grube, Martin; Cernava, Tomislav; Soh, Jung; Fuchs, Stephan; Aschenbrenner, Ines; Lassek, Christian; Wegner, Uwe; Becher, Dörte; Riedel, Katharina; Sensen, Christoph W; Berg, Gabriele

    2015-01-01

    Symbioses represent a frequent and successful lifestyle on earth and lichens are one of their classic examples. Recently, bacterial communities were identified as stable, specific and structurally integrated partners of the lichen symbiosis, but their role has remained largely elusive in comparison to the well-known functions of the fungal and algal partners. We have explored the metabolic potentials of the microbiome using the lung lichen Lobaria pulmonaria as the model. Metagenomic and proteomic data were comparatively assessed and visualized by Voronoi treemaps. The study was complemented with molecular, microscopic and physiological assays. We have found that more than 800 bacterial species have the ability to contribute multiple aspects to the symbiotic system, including essential functions such as (i) nutrient supply, especially nitrogen, phosphorous and sulfur, (ii) resistance against biotic stress factors (that is, pathogen defense), (iii) resistance against abiotic factors, (iv) support of photosynthesis by provision of vitamin B12, (v) fungal and algal growth support by provision of hormones, (vi) detoxification of metabolites, and (vii) degradation of older parts of the lichen thallus. Our findings showed the potential of lichen-associated bacteria to interact with the fungal as well as algal partner to support health, growth and fitness of their hosts. We developed a model of the symbiosis depicting the functional multi-player network of the participants, and argue that the strategy of functional diversification in lichens supports the longevity and persistence of lichens under extreme and changing ecological conditions. PMID:25072413

  2. Study on the transplant impact on the elementary composition of Protousnea magellanica thallus by using instrumental neutron activation analysis

    International Nuclear Information System (INIS)

    Bubach, Debora; Guevara, Sergio Ribeiro; Arribere, Maria A.; Wiesztort, Andres; Calvelo, Susana

    1999-01-01

    As part of a study on the use of the furticose lichen Protousnea magellanica as a bio indicator of atmospheric pollution, it was studied the impact on the elemental composition of the thallus when this lichen is transplanted in the same area under similar environmental conditions. The lichens were collected and replanted in a pristine area in Puerto Blest, Nahuel Huapi National Park, Bariloche, Argentina. After one year, the transplanted thalli were collected and analyzed by using Instrumental Activation Analysis, complemented with Atomic Absorption Spectrophotometry for the Pb content determination. Crustal inputs were identified by computing enrichment factors. The transplanted thalli concentrations of most of the elements under study, Al, As, Ba, Ce, Co, Cr, Dy, Eu, Hg, Fe, La, Lu, Mn, Na, Pb, Sb, Sc, Sm, Sr, Tb, Ti, Th, V, Yb and Zn, showed no significant differences with respect to the control thalli. However, some biological elements, Ca, Cl, Br, K and Rb, showed significant variations with respect to the controls, more noticeable in the first two elements. (author)

  3. The lichen Parmelia physodes (L. Ach. as indicator for determination of the degree of atmospheric air pollution in the area contaminated by flourine and sulphur dioxide emission

    Directory of Open Access Journals (Sweden)

    M. Świeboda

    2015-01-01

    Full Text Available On the area involved in the influence of conteminations emitted by the aluminium works and electric power plant, the degree of atmospheric air pollution was evaluated on the basis of the behaviour of healthy thallus of the lichen Parmelia physodes, analysis of fluorine and sulphur content in this thallus and in the bark substrate and the F and SO2 concentrations in the air.

  4. Content of certain mineral components in the thallus of lichens and the bark of roadside trees

    Directory of Open Access Journals (Sweden)

    Stanisława Kuziel

    2015-01-01

    Full Text Available The total N, P, Mg, Ca, K and Na contents were investigated in the thalli of several lichen species occurring on various trees, and in the bark and bark extracts from these trees. pH of the bark extracts was also determined. Wide differences were found in the content of the elements in point in the thalli of various lichen species on Acer platanoides and on the thalli of the same species on other trees. No relation was detected between the chemical composition of the bark and that of the lichen thalli occurring on it.

  5. Trace element patterns in lichens following uranium mine closures

    International Nuclear Information System (INIS)

    Fahselt, D.; Wu, T.W.; Mott, B.

    1995-01-01

    Instrumental neutron activation analysis was used to determine trace elements in Cladina mitis (Sandst). Hale ampersand Culb. along transects extending from uranium mines at Elliot Lake and Agnew Lake in central Ontario, Canada. Levels of 11 elements were reported and the presence of uranium (U) was confirmed, although U concentrations were much less than in Cladina rangiferina 10 years earlier. Among the elements identified in lichen thalli was Th, which occurred in higher concentrations than U. All trace elements, including the two radionuclides, were found in deteriorating thallus parts as well as living podetia, and five of these seem to have originated as airborne particulates from minesites. In spite of mine closures, levels of Th and U remained higher near sources of ore dust and there was little relationship between radionuclide concentrations in thallus and substrate. 24 refs., 4 figs., 3 tabs

  6. 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.

  7. The application of lichens as ecological surrogates of air pollution in the subtropics: a case study in South Brazil.

    Science.gov (United States)

    Koch, Natália M; Branquinho, Cristina; Matos, Paula; Pinho, Pedro; Lucheta, Fabiane; Martins, Suzana M A; Vargas, Vera M F

    2016-10-01

    The use of lichens as ecological surrogates has been an important tool to evaluate the impact of air pollution in both ecosystem and human health but remains underused in the subtropics due to lack of knowledge. Aiming to support the application of lichen as ecological surrogates of the effects of air pollution in the subtropics, we hypothesized that urbanization was an important driver of changes on lichen diversity, composition, and vitality. For that, we quantified several lichen diversity metrics (richness, cover, and community composition) and photobiont vitality in relation to atmospheric pollution or its surrogates (modeled pollutant gases, pollutants in lichen thallus, and land cover). We confirmed that air pollution was a key driver for lichen diversity. Changes in lichen community composition and vitality were very significantly related to air pollution and integrated the effect of multiple stressors (particulate matter, NOx, and Cu), thus being powerful ecological indicators of air pollution in the subtropics.

  8. Some aspects of the effect of atmospheric pollution on the lichen flora to the west of Consett Co. , Durham

    Energy Technology Data Exchange (ETDEWEB)

    Griffith, J L

    1966-01-01

    The effect of atmospheric pollution on the growth of lichens has long been discussed. This work was aimed at obtaining data on the effect of such pollution, from the Iron and Steel works at Consett Co. Durham, on the lichen flora of the district. The degree of pollution found to the west of Consett was evaluated by analysis of lichen thallus for sulfur and from bark washings for amounts of deposited matter. These results were compared with standard pollution data at Consett, obtained from the DSIR, and a pollution gradient passing west from Consett was plotted. The distribution of corticolous, saxicolous and terricolous lichens in this area was mapped. The results from these distributions were applied to the pollution data and the control of lichens by pollution shown. The modification of the pollution effect by humidity factors is also discussed.

  9. Influence of wavelength on the laser removal of lichens colonizing heritage stone

    International Nuclear Information System (INIS)

    Sanz, M.; Oujja, M.; Ascaso, C.; Pérez-Ortega, S.; Souza-Egipsy, V.; Fort, R.; Rios, A. de los; Wierzchos, J.; Cañamares, M.V.; Castillejo, M.

    2017-01-01

    Highlights: • Optimal laser removal conditions depend on light absorption of lichen species. • Highly UV absorbing species (C. vitellina) removed by 266 nm nanosecond pulses. • Dual 1064-266/355 nm irradiation strongly damages a large variety of lichen species. • Calcium inside the lichen thallus prevents the damaging effect of laser irradiation. - Abstract: Laser irradiation of lichen thalli on heritage stones serves for the control of epilithic and endolithic biological colonizations. In this work we investigate rock samples from two quarries traditionally used as source of monumental stone, sandstone from Valonsadero (Soria, Spain) and granite from Alpedrete (Madrid, Spain), in order to find conditions for efficient laser removal of lichen thalli that ensure preservation of the lithic substrate. The samples presented superficial areas colonized by different types of crustose lichens, i.e. Candelariella vitellina, Aspicilia viridescens, Rhizocarpon disporum and Protoparmeliopsis muralis in Valonsadero samples and P. cf. bolcana and A. cf. contorta in Alpedrete samples. A comparative laser cleaning study was carried out on the mentioned samples with ns Q-switched Nd:YAG laser pulses of 1064 nm (fundamental radiation), 355 nm (3rd harmonic) and 266 nm (4th harmonic) and sequences of IR-UV pulses. A number of techniques such as UV-Vis absorption spectroscopy, stereomicroscopy, scanning electron microscopy (SEM) at low vacuum, SEM with backscattered electron imaging (SEM-BSE), electron dispersive spectroscopy (EDS) and FT-Raman spectroscopy were employed to determine the best laser irradiation conditions and to detect possible structural, morphological and chemical changes on the irradiated surfaces. The results show that the laser treatment does not lead to the complete removal of the studied lichen thalli, although clearly induces substantial damage, in the form of loss of the lichen upper cortex and damage to the algal layer. In the medium term these

  10. Influence of wavelength on the laser removal of lichens colonizing heritage stone

    Energy Technology Data Exchange (ETDEWEB)

    Sanz, M., E-mail: mikel.sanz@iqfr.csic.es [Instituto de Química Física Rocasolano (IQFR-CSIC), Serrano 119, 28006, Madrid (Spain); Oujja, M. [Instituto de Química Física Rocasolano (IQFR-CSIC), Serrano 119, 28006, Madrid (Spain); Ascaso, C. [Museo Nacional de Ciencias Naturales (MNCN-CSIC), José Gutiérrez Abascal 2, 28006, Madrid (Spain); Pérez-Ortega, S. [Real Jardín Botánico (RJB-CSIC), Plaza de Murillo 2, 28014, Madrid (Spain); Souza-Egipsy, V. [Instituto de Estructura de la Materia (IEM-CSIC), Serrano 121, 28006, Madrid (Spain); Fort, R. [Instituto de Geociencias (IGEO-CSIC, UCM), José Antonio Nováis 12, 28040, Madrid (Spain); Rios, A. de los; Wierzchos, J. [Museo Nacional de Ciencias Naturales (MNCN-CSIC), José Gutiérrez Abascal 2, 28006, Madrid (Spain); Cañamares, M.V. [Instituto de Estructura de la Materia (IEM-CSIC), Serrano 121, 28006, Madrid (Spain); Castillejo, M. [Instituto de Química Física Rocasolano (IQFR-CSIC), Serrano 119, 28006, Madrid (Spain)

    2017-03-31

    Highlights: • Optimal laser removal conditions depend on light absorption of lichen species. • Highly UV absorbing species (C. vitellina) removed by 266 nm nanosecond pulses. • Dual 1064-266/355 nm irradiation strongly damages a large variety of lichen species. • Calcium inside the lichen thallus prevents the damaging effect of laser irradiation. - Abstract: Laser irradiation of lichen thalli on heritage stones serves for the control of epilithic and endolithic biological colonizations. In this work we investigate rock samples from two quarries traditionally used as source of monumental stone, sandstone from Valonsadero (Soria, Spain) and granite from Alpedrete (Madrid, Spain), in order to find conditions for efficient laser removal of lichen thalli that ensure preservation of the lithic substrate. The samples presented superficial areas colonized by different types of crustose lichens, i.e. Candelariella vitellina, Aspicilia viridescens, Rhizocarpon disporum and Protoparmeliopsis muralis in Valonsadero samples and P. cf. bolcana and A. cf. contorta in Alpedrete samples. A comparative laser cleaning study was carried out on the mentioned samples with ns Q-switched Nd:YAG laser pulses of 1064 nm (fundamental radiation), 355 nm (3rd harmonic) and 266 nm (4th harmonic) and sequences of IR-UV pulses. A number of techniques such as UV-Vis absorption spectroscopy, stereomicroscopy, scanning electron microscopy (SEM) at low vacuum, SEM with backscattered electron imaging (SEM-BSE), electron dispersive spectroscopy (EDS) and FT-Raman spectroscopy were employed to determine the best laser irradiation conditions and to detect possible structural, morphological and chemical changes on the irradiated surfaces. The results show that the laser treatment does not lead to the complete removal of the studied lichen thalli, although clearly induces substantial damage, in the form of loss of the lichen upper cortex and damage to the algal layer. In the medium term these

  11. Effects of chronic gamma radiation on the lichen Parmelia sulcata Tayl. in the Enterprise Radiation Forest

    International Nuclear Information System (INIS)

    Erbisch, F.H.

    1977-01-01

    Within the Enterprise Radiation Forest, the foliose lichen Parmelia sulcata Tayl. exhibited radiation damage. Only those lichens which received in excess of 100 krad manifested damage. The damage was evidenced as a lifting and subsequent breaking of lobes, a coalescing of fungal hyphae, a formation of a brown pigment by the coalescing hyphae, a distortion of the chloroplastid of the algal component, and eventual death of the lichen. The radiation also affected thallus growth by slowing it and rhizinae branching by increasing the number of branches. Damage was not manifested until the late spring (June) of the year following radiation. Apparently P. sulcata is able to maintain itself until conditions are favorable for growth, after receiving a large dose of gamma radiation. Under favorable growth conditions, the lichen cannot carry out its normal growth functions and deteriorates. Although environmental changes did occur within the forest, evidence obtained indicates that gamma radiation was the principal factor affecting the lichens

  12. The effect of thallus spreading method on productivity of Gracilaria sp. culture

    Science.gov (United States)

    Hidayatulbaroroh, R.; Nurhudah, M.; Edy, M. H.; Suharyadi

    2018-04-01

    The aim of this study was to determine growth of (Gracilaria sp.) with different spreading time of thallus. The study was conducted from March to April 2017 in pond located in Domas Village, Serang Region, Banten Province. The experiment followed completely randomized design with the treatment of different time on spreading of seaweed thallus during the culture period (45 days). Treatments were without spreading (as control), spreading every 2 weeks, and spreading every 3 weeks. The observed variables were weight of seaweed thallus and several water quality parameters. Analysis of seaweed weight used ANOVA test and Tukey HSD test. The results showed that the spread seaweed thallus had a significant effect on weight gain in 0.05 level. It used 100 gram Gracilaria sp. as initial weight, treatment without spreading thallus produced 508 gram, spreading every 2 weeks produced 906 gram and spreading every 3 weeks produced 790 gram. Based on the weight gain of thallus, seaweed culture by spreading thallus every 3 weeks and 2 weeks seem to be able to increase productivity by 56 % and 78 %, respectively.

  13. 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

  14. 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.

  15. 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

  16. 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

  17. Different Heavy Metal Accumulation Strategies of Epilithic Lichens Colonising Artificial Post-Smelting Wastes.

    Science.gov (United States)

    Rola, Kaja; Osyczka, Piotr; Kafel, Alina

    2016-02-01

    Lichens appear to be essential and effective colonisers of bare substrates including the extremely contaminated wastes of slag dumps. This study examines the metal accumulation capacity of epilithic lichens growing directly on the surface of artificial slag sinters. Four species representing different growth forms, i.e., crustose Candelariella aurella, Lecanora muralis, and Lecidea fuscoatra and fruticose Stereocaulon nanodes, were selected to evaluate the relationships between zinc, lead, cadmium, and nickel contents in their thalli and host substrates. Bioaccumulation factors of examined crustose lichens showed their propensity to hyperaccumulate heavy metals. Contrarily, concentrations of metals in fruticose thalli of S. nanodes were, as a rule, lower than in the corresponding substrates. This indicates that the growth form of thalli and degree of thallus adhesion to the substrate has a significant impact on metal concentrations in lichens colonising post-smelting wastes. Nonlinear regression models described by power functions show that at greater levels of Pb concentration in the substrate, the ability of C. aurella, L. muralis and L. fuscoatra to accumulate the metal experiences a relative decrease, whereas hyperbolic function describes a similar trend in relation to Ni content in S. nanodes. This phenomenon may be an important attribute of lichens that facilitates their colonisation of the surface of slag wastes.

  18. Comparison of five physiological parameters to assess the vitality of the lichen Ramalina lacerea exposed to air pollution

    Energy Technology Data Exchange (ETDEWEB)

    Garty, J.; Weissman, L.; Tamir, O.; Cohen, Y. [Tel Aviv Univ., The George S. Wise Faculty of Life Sciences, Inst. for Natur Conservation Research , Ramat Aviv (Israel); Beer, S. [Tel Aviv Univ., The George S. Wise Faculty of Life Sciences, Dept. of Plant Sciences, Ramat Aviv (Israel); Orlovsky, L. [Ben Gurion Univ., J. Blaustein Inst. for Desert Research, The Remote Sensing Lab., Sede-Boker Campus (Israel)

    2000-07-01

    To determine the environmental impact of industrial activity, we examined and compared the following parameters of physiological integrity in the epiphytic fruticose lichen Ramalina lacera. (1) Potential quantum yield of PSII expressed as the chlorophyll fluorescence ratio F{sub v}/F{sub m}. (2) Spectral reflectance expressed as values of normalized difference vegetation index (NDVI). (3) Production of ethylene. (4) Electrolyte leakage brought about by degrading cell membranes in terms of electric conductivity. (5) The ratio A{sub 435nm}/A{sub 415nm} indicating the disintegration of chlorophyll. The amounts of Ba, Cu, K, Ni, S, V and Zn contained in the lichen thallus were measured to quantify the degree of pollution. Some of the lichen-carrying twigs collected at a relatively unpolluted control site were resuspended on the original trees as controls. Other lichens were transplanted to 19 bio-monitoring sites. Transplanted lichens in polluted sites contained higher amounts of Ba, Ni, S, V and Zn than lichens in the control site and in most of the rural sites upon an exposure period of 8 months. Statistical analysis revealed negative correlations between F{sub v}/F{sub m} ratios and Ba contents of transplants. High Ba, Cu, Ni and Zn contents correlated negatively with NDVI values. NDVI values correlated with A{sub 435nm}/A{sub 415nm}, F{sub v}/F{sub m} and K. The ratio A{sub 435nm}/A{sub 415nm} correlated positively with K and negatively with Ba, Cu and Zn. The production of ethylene correlated positively with Cu and Ba and negatively with A{sub 435nm}/A{sub 415nm}, F{sub v}/F{sub m} and NDVI. Electric conductivity values correlated positively with Ba, Cu, Na, S, V and Zn and negatively with NDVI. Both elemental content and physiological alterations in transplants of R. lacera point to a high degree of contamination in the Haifa Bay region, which is polluted by fuel-oil combustion apart from other industrial activities. The present work suggests that in our specific

  19. Comparative demography of an epiphytic lichen: support for general life history patterns and solutions to common problems in demographic parameter estimation.

    Science.gov (United States)

    Shriver, Robert K; Cutler, Kerry; Doak, Daniel F

    2012-09-01

    Lichens are major components in many terrestrial ecosystems, yet their population ecology is at best only poorly understood. Few studies have fully quantified the life history or demographic patterns of any lichen, with particularly little attention to epiphytic species. We conducted a 6-year demographic study of Vulpicida pinastri, an epiphytic foliose lichen, in south-central Alaska. After testing multiple size-structured functions to describe patterns in each V. pinastri demographic rate, we used the resulting estimates to construct a stochastic demographic model for the species. This model development led us to propose solutions to two general problems in construction of demographic models for many taxa: how to simply but accurately characterize highly skewed growth rates, and how to estimate recruitment rates that are exceptionally difficult to directly observe. Our results show that V. pinastri has rapid and variable growth and, for small individuals, low and variable survival, but that these traits are coupled with considerable longevity (e.g., >50 years mean future life span for a 4-cm(2) thallus) and little deviation of the stochastic population growth rate from the deterministic expectation. Comparisons of the demographic patterns we found with those of other lichen studies suggest that their relatively simple architecture may allow clearer generalities about growth patterns for lichens than for other taxa, and that the expected pattern of faster growth rates for epiphytic species is substantiated.

  20. 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.

  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. The adaptive radiation of lichen-forming Teloschistaceae is associated with sunscreening pigments and a bark-to-rock substrate shift.

    Science.gov (United States)

    Gaya, Ester; Fernández-Brime, Samantha; Vargas, Reinaldo; Lachlan, Robert F; Gueidan, Cécile; Ramírez-Mejía, Martín; Lutzoni, François

    2015-09-15

    Adaptive radiations play key roles in the generation of biodiversity and biological novelty, and therefore understanding the factors that drive them remains one of the most important challenges of evolutionary biology. Although both intrinsic innovations and extrinsic ecological opportunities contribute to diversification bursts, few studies have looked at the synergistic effect of such factors. Here we investigate the Teloschistales (Ascomycota), a group of >1,000 lichenized species with variation in species richness and phenotypic traits that hinted at a potential adaptive radiation. We found evidence for a dramatic increase in diversification rate for one of four families within this order--Teloschistaceae--which occurred ∼ 100 Mya (Late Cretaceous) and was associated with a switch from bark to rock and from shady to sun-exposed habitats. This adaptation to sunny habitats is likely to have been enabled by a contemporaneous key novel phenotypic innovation: the production in both vegetative structure (thallus) and fruiting body (apothecia) of anthraquinones, secondary metabolites known to protect against UV light. We found that the two ecological factors (sun exposure and rock substrate) and the phenotypic innovation (anthraquinones in the thallus) were all significant when testing for state-dependent shifts in diversification rates, and together they seem likely to be responsible for the success of the Teloschistaceae, one of the largest lichen-forming fungal lineages. Our results support the idea that adaptive radiations are driven not by a single factor or key innovation, but require a serendipitous combination of both intrinsic biotic and extrinsic abiotic and ecological factors.

  3. 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.

  4. Successful lichen translocation on disturbed gypsum areas: A test with adhesives to promote the recovery of biological soil crusts

    Science.gov (United States)

    Ballesteros, M.; Ayerbe, J.; Casares, M.; Cañadas, E. M.; Lorite, J.

    2017-04-01

    The loss of biological soil crusts represents a challenge for the restoration of disturbed environments, specifically in particular substrates hosting unique lichen communities. However, the recovery of lichen species affected by mining is rarely addressed in restoration projects. Here, we evaluate the translocation of Diploschistes diacapsis, a representative species of gypsum lichen communities affected by quarrying. We tested how a selection of adhesives could improve thallus attachment to the substrate and affect lichen vitality (as CO2 exchange and fluorescence) in rainfall-simulation and field experiments. Treatments included: white glue, water, hydroseeding stabiliser, gum arabic, synthetic resin, and a control with no adhesive. Attachment differed only in the field, where white glue and water performed best. Adhesives altered CO2 exchange and fluorescence yield. Notably, wet spoils allowed thalli to bind to the substrate after drying, revealing as the most suitable option for translocation. The satisfactory results applying water on gypsum spoils are encouraging to test this methodology with other lichen species. Implementing these measures in restoration projects would be relatively easy and cost-effective. It would help not only to recover lichen species in the disturbed areas but also to take advantage of an extremely valuable biological material that otherwise would be lost.

  5. Response of the nitrogen-fixing lichen Lobaria pulmonaria to phosphorus, molybdenum, and vanadium

    Science.gov (United States)

    Marks, Jade A; Pett-Ridge, Julie; Perakis, Steven S.; Allen, Jessica L; McCune, Bruce

    2015-01-01

    Nitrogen-fixing lichens (cyanolichens) are an important source of nitrogen (N) in Pacific Northwest forests, but limitation of lichen growth by elements essential for N fixation is poorly understood. To investigate how nutrient limitation may affect cyanolichen growth rates, we fertilized a tripartite cyanobacterial lichen (Lobaria pulmonaria) and a green algal non-nitrogen fixing lichen (Usnea longissima) with the micronutrients molybdenum (Mo) and vanadium (V), both known cofactors for enzymes involved in N fixation, and the macronutrient phosphorus (P). We then grew treated lichens in the field for one year in western Oregon, USA. Lichen growth was very rapid for both species and did not differ across treatments, despite a previous demonstration of P-limitation in L. pulmonaria at a nearby location. To reconcile these disparate findings, we analyzed P, Mo, and V concentrations, natural abundance δ15N isotopes, %N and change in thallus N in Lobaria pulmonaria from both growth experiments. Nitrogen levels in deposition and in lichens could not explain the large difference in growth or P limitation observed between the two studies. Instead, we provide evidence that local differences in P availability may have caused site-specific responses of Lobaria to P fertilization. In the previous experiment, Lobaria had low background levels of P, and treatment with P more than doubled growth. In contrast, Lobaria from the current experiment had much higher background P concentrations, similar to P-treated lichens in the previous experiment, consistent with the idea that ambient variation in P availability influences the degree of P limitation in cyanolichens. We conclude that insufficient P, Mo, and V did not limit the growth of either cyanolichens or chlorolichens at the site of the current experiment. Our findings point to the need to understand landscape-scale variation in P availability to cyanolichens, and its effect on spatial patterns of cyanolichen nutrient

  6. 14C/C measurements support Andreev's internode method to determine lichen growth rates in Cladina stygia (Fr.) Ahti

    Energy Technology Data Exchange (ETDEWEB)

    Holt, E; Bench, G

    2007-12-05

    Growth rates and the ability to date an organism can greatly contribute to understanding its population biology and community dynamics. 1n 1954, Andreev proposed a method to date Cladina, a fruticose lichen, using total thallus length and number of internodes. No research, however, has demonstrated the reliability of this technique or compared its estimates to those derived by other means. In this study, we demonstrate the utility of {sup 14}C/C ratios to determine lichen age and growth rate in Cladina stygia (Fr.) Ahti collected from northwestern Alaska, USA. The average growth rate using {sup 14}C/C ratios was 6.5 mm {center_dot} yr{sup -1}, which was not significantly different from growth rates derived by Andreev's internode method (average = 6.2 mm {center_dot} yr{sup -1}); thus, suggesting the reliability of Andreev's simple field method for dating lichens. In addition, we found lichen growth rates appeared to differ with geographic location, yet did not seem related to ambient temperature and total precipitation.

  7. Use of micro-PIXE in the study of arsenate uptake in lichens and its influence on element distribution and concentrations

    Energy Technology Data Exchange (ETDEWEB)

    Mrak, T. [Department of Environmental Sciences, Jozef Stefan Institute, Jamova 39, P.O.B. 3000, SI-1001 Ljubljana (Slovenia); Simcic, J. [Department of Low and Medium Energy Physics, Jozef Stefan Institute, Jamova 39, P.O.B. 3000, SI-1001 Ljubljana (Slovenia); Pelicon, P. [Department of Low and Medium Energy Physics, Jozef Stefan Institute, Jamova 39, P.O.B. 3000, SI-1001 Ljubljana (Slovenia)]. E-mail: primoz.pelicon@ijs.si; Jeran, Z. [Department of Environmental Sciences, Jozef Stefan Institute, Jamova 39, P.O.B. 3000, SI-1001 Ljubljana (Slovenia); Reis, M.A. [ITN - Nuclear and Technology Institute, EN 10 Sacavem, Apartado 21, 2686-953 Sacavem (Portugal); Pinheiro, T. [ITN - Nuclear and Technology Institute, EN 10 Sacavem, Apartado 21, 2686-953 Sacavem (Portugal); Nuclear Physics Centre, Lisbon University, Av. Prof. Gama Pinto 2, 1649-003 Lisbon (Portugal)

    2007-07-15

    Micro-PIXE was applied in the study of arsenic metabolism in the lichen Hypogymnia physodes (L.) Nyl. Lichen thalli were laboratory exposed to a solution of an inorganic arsenic compound arsenate and to a control solution. Perpendicular sections that reveal the morphological properties of the lichen thallus were subjected to microbeam measurements to obtain data on the localization of arsenic and its influence on the distribution and concentrations of the selected macro- and microelements P, S, K, Ca, Cl, Mn, Fe and Zn. Five groups of elements were distinguished regarding losses and redistribution due to arsenic exposure: (1) K and Ca were depleted from all lichen layers; (2) Mn was depleted from the algal layer and lower cortex, (3) Fe was decreased in the algal layer and increased in the lower cortex, (4) Zn was decreased both in the algal layer and the medulla, but increased in the lower cortex, and (5) P and S were decreased in the medulla, but increased in the algal layer and the lower cortex.

  8. Understanding Microbial Multi-Species Symbioses

    Science.gov (United States)

    Aschenbrenner, Ines A.; Cernava, Tomislav; Berg, Gabriele; Grube, Martin

    2016-01-01

    Lichens are commonly recognized as a symbiotic association of a fungus and a chlorophyll containing partner, either green algae or cyanobacteria, or both. The fungus provides a suitable habitat for the partner, which provides photosynthetically fixed carbon as energy source for the system. The evolutionary result of the self-sustaining partnership is a unique joint structure, the lichen thallus, which is indispensable for fungal sexual reproduction. The classical view of a dual symbiosis has been challenged by recent microbiome research, which revealed host-specific bacterial microbiomes. The recent results about bacterial associations with lichens symbioses corroborate their notion as a multi-species symbiosis. Multi-omics approaches have provided evidence for functional contribution by the bacterial microbiome to the entire lichen meta-organism while various abiotic and biotic factors can additionally influence the bacterial community structure. Results of current research also suggest that neighboring ecological niches influence the composition of the lichen bacterial microbiome. Specificity and functions are here reviewed based on these recent findings, converging to a holistic view of bacterial roles in lichens. Finally we propose that the lichen thallus has also evolved to function as a smart harvester of bacterial symbionts. We suggest that lichens represent an ideal model to study multi-species symbiosis, using the recently available omics tools and other cutting edge methods. PMID:26925047

  9. Study on the transplant impact on the elementary composition of Protousnea magellanica thallus by using instrumental neutron activation analysis; Estudio del impacto del transplante en la composicion elemental de Protousnea magellanica utilizando analisis por activacion neutronica instrumental

    Energy Technology Data Exchange (ETDEWEB)

    Bubach, Debora; Guevara, Sergio Ribeiro; Arribere, Maria A.; Wiesztort, Andres [Comision Nacional de Energia Atomica, San Carlos de Bariloche (Argentina). Centro Atomico Bariloche. Lab. de Analisis por Activacion Nautronica; Calvelo, Susana [Universidad Nacional del Comahue, Bariloche (Argentina). Centro Regional Universitario Bariloche

    1999-11-01

    As part of a study on the use of the furticose lichen Protousnea magellanica as a bio indicator of atmospheric pollution, it was studied the impact on the elemental composition of the thallus when this lichen is transplanted in the same area under similar environmental conditions. The lichens were collected and replanted in a pristine area in Puerto Blest, Nahuel Huapi National Park, Bariloche, Argentina. After one year, the transplanted thalli were collected and analyzed by using Instrumental Activation Analysis, complemented with Atomic Absorption Spectrophotometry for the Pb content determination. Crustal inputs were identified by computing enrichment factors. The transplanted thalli concentrations of most of the elements under study, Al, As, Ba, Ce, Co, Cr, Dy, Eu, Hg, Fe, La, Lu, Mn, Na, Pb, Sb, Sc, Sm, Sr, Tb, Ti, Th, V, Yb and Zn, showed no significant differences with respect to the control thalli. However, some biological elements, Ca, Cl, Br, K and Rb, showed significant variations with respect to the controls, more noticeable in the first two elements. (author) 18 refs., 1 fig., 2 tabs.

  10. Short-term influence of Cu, Zn, Ni and Cd excess on metabolism, ultrastructure and distribution of elements in lichen Xanthoria parietina (L.) Th. Fr.

    Science.gov (United States)

    Piovár, J; Weidinger, M; Bačkor, M; Bačkorová, M; Lichtscheidl, I

    2017-11-01

    Lichens are symbiotic organisms that are very sensitive to heavy metal pollution. However, there is little evidence of how heavy metal pollution affects the physiological status, ultrastructural changes and distribution of elements in the layers of lichen thalli. For this purpose we simulated metal pollution to lichens and studied its impact on Xanthoria parietina. Thalli were treated with the heavy metals Cu, Zn, Ni, Cd in the form of sulfates at concentrations of 100µM and 500µM during 24, 48 and 72h. Untreated lichens served as controls. We assessed the status of physiological parameters (fluorescence and integrity of chlorophyll a, content of soluble proteins and ergosterol), ultrastructural changes, especially to the photobiont, and the distribution of elements in the layers of thalli in relation to treatment with heavy metals. We found positive correlations between the content of all tested heavy metals and the physiological response. We assessed the toxicity of the selected metals as follows: Cd >= Cu >= Ni > Zn, based on the effects on the photobiont layer in the lichen thallus and physiological measurements. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. 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...

  12. Role of lichens in weathering of granodiorite in the Sila uplands (Calabria, southern Italy)

    Science.gov (United States)

    Scarciglia, Fabio; Saporito, Natalina; La Russa, Mauro F.; Le Pera, Emilia; Macchione, Maria; Puntillo, Domenico; Crisci, Gino M.; Pezzino, Antonino

    2012-12-01

    This paper explores the role of five recurrent epilithic lichen species (Aspicilia intermutans (Nyl.) Arnold, Xanthoparmelia pulla (Ach.) O. Blanco, A. Crespo, Elix, D. Hawksw. & Lumbsch, Rhizocarpon lecanorinum Anders, Tephromela atra (Huds.) Hafellner and Lecanora bolcana (Pollini) Poelt), which encrust granodiorite spheroidal boulders exposed in the Sila uplands (Calabria, southern Italy), in weathering of plutonic rocks in a typical mountainous Mediterranean environment. A detailed investigation was carried out on the lichen-rock interface of each species, by comparing them mutually and with lichen-free granodiorite samples. For this purpose, the lichen species were sampled together with the encrusted rock surface for detailed mineral-petrographic analyses performed in thin and ultra-thin sections. Optical and scanning electron microscopy of these sections and of bulk samples permitted us to highlight the peculiar modes of physical and chemical attacks of lichen thalli and hyphae on and into the substratum for each species. Crack systems often parallel to the outer rock surface appear often intruded by hyphae, which cause rupture of primary minerals, with detachment and progressive incorporation of their fragments into the thallus. In particular, the species L. bolcana and T. atra revealed an unexpected, partly endolithic behavior, presumably enhanced by the presence of rock fractures earlier generated by other physical breakage processes already affecting the spheroidal boulders in the Sila mountains. Dissolution features often affect primary minerals (even quartz), that may show very peculiar patterns which are suggestive of a biologically-induced control. Various phyllosilicate clay minerals were identified using SEM-EDS microprobe analyses and FT-IR spectroscopy, which also enabled the identification of possible amorphous silica (or quartz micrograins), rhizocarpic acid and carotenoid at the encrusted granodiorite interface. In contrast, neither oxalic

  13. Effects of nitrogen enrichment on phosphatase activity and nitrogen : phosphorus relationships in Cladonia portentosa.

    Science.gov (United States)

    Hogan, E J; Minnullina, G; Smith, R I; Crittenden, P D

    2010-06-01

    *Relationships between nitrogen deposition in the UK and phosphomonoesterase (PME) activity and nitrogen (N) and phosphorus (P) concentrations in Cladonia portentosa were quantified to understand factors limiting lichen growth and to further develop biomarkers for N pollution. *Lichen was collected from sites differing either in rates of wet N (NH(4)(+) + NO(3)(-)) deposition or in annual mean N concentration in rainfall based on both measured and modelled data sets. The PME activity, and total N and P concentrations were measured in specific horizontal strata in lichen mats and PME activity in the thallus was located using an enzyme-labelled fluorescent phosphatase substrate. *With an increase in modelled N deposition from 4.1 to 32.8 kg N ha(-1) yr(-1), PME activity, thallus N and N : P ratio increased by factors of 2.3, 1.4 and 1.8, respectively. Correlations with modelled data were generally stronger than with measured data and those with N deposition were stronger than those with N concentration in rainfall. The PME activity was located solely in the lichen fungus in outer regions of the thallus. *Nitrogen enrichment changes lichen N : P ratios from values typical of N limitation (for example, 10) to those indicative of P limitation (for example, 26) driving upregulation of PME activity.

  14. 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.

  15. 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.

  16. MALAYSIAN LICHENS—III*

    Directory of Open Access Journals (Sweden)

    P. GROBNHART

    2015-11-01

    Full Text Available Amongst the lichens sent by the late Mr C. C. Schroter at Tjibodas (West Java, a peculiar blue-grey species drew my attention. At first sight I intended to assign it provisionally to Collemaceae indeterminatae, but on closer examination I doubted whether it was really a species of Collemaceae. Therefore. I examined it more carefully, with the following result. The granular thallus grows in smaller to larger patches over mosses, lichens, and detritus on bark. Soredia and isidia are absent and the thallus is not surrounded by a dark hypothalline line. The granular appearance of the thallus is caused by the relatively large gonidia, which belong to Stygonemataceae. The yellowish green cells are rounded, angular to semilunate, 8—12µ, wide and 10—15 µ long; one or more of them are enclosed within a gelatinous, colourless to pale citrine sheeth 4—6 µ thick. These clusters of gonidia are held together by the thalline hyphae constituting in this way a homoiomeric thallus. There is some resemblance with the thallus of Moriolaceae but in this family the gonidia are totally surrounded with a network of short hyphae lying close together. In the thallus of Cyanoporina, as I call this new lichen, such a network does not exist. The hyphae lie irregularly around the gonidia and cover them but partly. These gonidial hyphae are 2—3µ thick and possess very short cells. The thalline hyphae are 3 µ, thick, with inconspicuous lumen. Even with the aid of a dissecting microscope the perithecia are almost* invisible. Most of them are covered by the granules of the thallus. Yet the thallus is abundantly fruiting and in sections perithecia are always present. They are globose, 110—130µ in diameter, pale fulvescent to yellowish, with a pseudoparenchymatic wall 10—12 µ thick, composed of densely interwoven hyphae. I could, not discover a pore. The paraphyses are diffluent and only fragments were found.

  17. 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

  18. 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

  19. 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

  20. Lichens and mosses in air quality monitoring: A biological model proposal; Licheni e briofite nella valutazione della qualita` ambientale: Proposta di un modello di bioaccumulo

    Energy Technology Data Exchange (ETDEWEB)

    Bari, A.; Minciardi, M. R. [ENEA, Centro Ricerche Saluggia, Vercelli (Italy). Dipt. Ambiente; Troiani, F.; Bonotto, F.; Paonessa, F.; Leone, D. [ENEA, Centro Ricerche Saluggia, Vercelli (Italy). Dipt. Energia; Piervittori, R.; Fossa, V.; Laccisaglia, A. [Turin, Univ. (Italy). Dipt. di Biologia Vegetale

    1997-09-01

    In the National Agency for New Technology, Energy and the Environment`s environmental monitoring studies, a research about the biomonitoring of metal pollution (Cd, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Zn) by lichens and mosses, in the extra-urban area of Saluggia (VC) was carried out in collaboration with University of Turin. The research, following a methodological approach, involved different plants and monitoring techniques. The mosses Grimmia pulvinata used as biomonitors were growing ``in situ`` on the contrary the lichens were transplanted. Several thallus of Pseudevernia furfuracea were collected from an uncontaminated area and exposed using two different techniques. The results confirmed the validity of such species as biomonitors of metal pollution. Although meaningful differences were pointed out between the different techniques, in many cases high accumulation rates were observed. A mathematical model of bioaccumulation was proposed, mainly to correlate the in-take of metals in the vegetal matrices with air metal concentrations and exposure time, obtaining a good experimental relationship.

  1. Do photobiont switch and cephalodia emancipation act as evolutionary drivers in the lichen symbiosis? A case study in the Pannariaceae (Peltigerales.

    Directory of Open Access Journals (Sweden)

    Nicolas Magain

    Full Text Available Lichen symbioses in the Pannariaceae associate an ascomycete and either cyanobacteria alone (usually Nostoc; bipartite thalli or green algae and cyanobacteria (cyanobacteria being located in dedicated structures called cephalodia; tripartite thalli as photosynthetic partners (photobionts. In bipartite thalli, cyanobacteria can either be restricted to a well-delimited layer within the thallus ('pannarioid' thalli or spread over the thallus that becomes gelatinous when wet ('collematoid' thalli. We studied the collematoid genera Kroswia and Physma and an undescribed tripartite species along with representatives of the pannarioid genera Fuscopannaria, Pannaria and Parmeliella. Molecular inferences from 4 loci for the fungus and 1 locus for the photobiont and statistical analyses within a phylogenetic framework support the following: (a several switches from pannarioid to collematoid thalli occured and are correlated with photobiont switches; the collematoid genus Kroswia is nested within the pannarioid genus Fuscopannaria and the collematoid genus Physma is sister to the pannarioid Parmeliella mariana group; (b Nostoc associated with collematoid thalli in the Pannariaceae are related to that of the Collemataceae (which contains only collematoid thalli, and never associated with pannarioid thalli; Nostoc associated with pannarioid thalli also associate in other families with similar morphology; (c ancestors of several lineages in the Pannariaceae developed tripartite thalli, bipartite thalli probably resulting from cephalodia emancipation from tripartite thalli which eventually evolved and diverged, as suggested by the same Nostoc present in the collematoid genus Physma and in the cephalodia of a closely related tripartite species; Photobiont switches and cephalodia emancipation followed by divergence are thus suspected to act as evolutionary drivers in the family Pannariaceae.

  2. 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.

  3. Reindeer lichen productivity: Problems and possibilities

    Directory of Open Access Journals (Sweden)

    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.

  4. 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.

  5. 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 ...

  6. 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.

  7. Variation in patterns of metal accumulation in thallus parts of Lessonia trabeculata (Laminariales; Phaeophyceae: implications for biomonitoring.

    Directory of Open Access Journals (Sweden)

    Claudio A Sáez

    Full Text Available Seaweeds are well known to concentrate metals from seawater and have been employed as monitors of metal pollution in coastal waters and estuaries. However, research showing that various intrinsic and extrinsic factors can influence metal accumulation, raises doubts about the basis for using seaweeds in biomonitoring programmes. The thallus of brown seaweeds of the order Laminariales (kelps is morphologically complex but there is limited information about the variation in metal accumulation between the different parts, which might result in erroneous conclusions being drawn if not accounted for in the biomonitoring protocol. To assess patterns of individual metals in the differentiated parts of the thallus (blade, stipe, holdfast, concentrations of a wide range of essential and non-essential metals (Fe, Cr, Cu, Zn, Mn, Pb, Cd, Ni and Al were measured in the kelp Lessonia trabeculata. Seaweeds were collected from three sampling stations located at 5, 30 and 60 m from an illegal sewage outfall close to Ventanas, Chile and from a pristine location at Faro Curaumilla. For the majority of metals the highest concentrations in bottom sediment and seaweed samples were found at the site closest to the outfall, with concentrations decreasing with distance from the outfall and at control stations; the exception was Cd, concentrations of which were higher at control stations. The patterns of metal concentrations in different thallus parts were metal specific and independent of sampling station. These results and the available literature suggest that biomonitoring of metals using seaweeds must take account of differences in the accumulation of metals in thallus parts of complex seaweeds.

  8. 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.

  9. Lichens as biological monitors in the Los Azufres geothermal field, Michoacan, Mexico; Liquenes como indicadores biologicos en el campo geotermico Los Azufres, Michoacan, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Gomez Peralta, Marlene; Chavez Carmona, Arturo [Universidad Michoacana de San Nicolas de Hidalgo, Morelia (Mexico)

    1995-09-01

    The results obtained in the monitoring of the atmospheric emissions of the Los Azufres geothermal field in Michoacan State, Mexico utilizing lichens as monitors of the presence of sulphur and arsenic, at the areas near geothermal sites, both under evaluation and production, are presented. The results are based on symptoms which included: chlorosis, necrosis, brown and reddish spots, loss of adherence to substrate, thalli disintegration and disappearance of sensitive species; and also on the amounts of sulphur and arsenic contained in the lichens thallus. [Espanol] Se presentan los resultados obtenidos en el monitoreo de las emisiones atmosfericas del campo geotermico Los Azufres, Michoacan, Mexico en el que se utilizaron liquenes como indicadores de la presencia de azufre y arsenico, en las areas cercanas a los sitios de pozos geotermicos tanto en evaluacion como en produccion. Los resultados estan basados en sintomas que incluyen clorosis, necrosis, manchas cafes y rojizas, perdida de adherencia al sustrato, desintegracion del talo y desaparicion de especies sensibles; asi como en los contenidos de azufre y arsenico en los talos liquenicos.

  10. Do Photobiont Switch and Cephalodia Emancipation Act as Evolutionary Drivers in the Lichen Symbiosis? A Case Study in the Pannariaceae (Peltigerales)

    Science.gov (United States)

    Magain, Nicolas; Sérusiaux, Emmanuël

    2014-01-01

    Lichen symbioses in the Pannariaceae associate an ascomycete and either cyanobacteria alone (usually Nostoc; bipartite thalli) or green algae and cyanobacteria (cyanobacteria being located in dedicated structures called cephalodia; tripartite thalli) as photosynthetic partners (photobionts). In bipartite thalli, cyanobacteria can either be restricted to a well-delimited layer within the thallus (‘pannarioid’ thalli) or spread over the thallus that becomes gelatinous when wet (‘collematoid’ thalli). We studied the collematoid genera Kroswia and Physma and an undescribed tripartite species along with representatives of the pannarioid genera Fuscopannaria, Pannaria and Parmeliella. Molecular inferences from 4 loci for the fungus and 1 locus for the photobiont and statistical analyses within a phylogenetic framework support the following: (a) several switches from pannarioid to collematoid thalli occured and are correlated with photobiont switches; the collematoid genus Kroswia is nested within the pannarioid genus Fuscopannaria and the collematoid genus Physma is sister to the pannarioid Parmeliella mariana group; (b) Nostoc associated with collematoid thalli in the Pannariaceae are related to that of the Collemataceae (which contains only collematoid thalli), and never associated with pannarioid thalli; Nostoc associated with pannarioid thalli also associate in other families with similar morphology; (c) ancestors of several lineages in the Pannariaceae developed tripartite thalli, bipartite thalli probably resulting from cephalodia emancipation from tripartite thalli which eventually evolved and diverged, as suggested by the same Nostoc present in the collematoid genus Physma and in the cephalodia of a closely related tripartite species; Photobiont switches and cephalodia emancipation followed by divergence are thus suspected to act as evolutionary drivers in the family Pannariaceae. PMID:24587091

  11. 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. ...

  12. 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)

  13. 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 ...

  14. 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.

  15. Ecological pattern of lichen species abundance in mixed forests of Eastern Romania

    Directory of Open Access Journals (Sweden)

    Ioana Vicol

    2016-12-01

    Full Text Available The importance of this study consists in the knowledge of the ecological attributes characteristic to mixed forestry habitats and how they affect the structure of the lichen species abundances. The field activities were performed within five forest habitat types from Moldavia Province, characterised mainly by oak mixed forests, riparian mixed forests and mixed beech forests. The habitat variables, tree variables and the lichen species abundances were analysed to get informations on the structural disimilarities, on the one hand, and relationships on the other hand. Within this study no significant disimilarities were found out from abundance lichen species point of view. The lichen species abundances are a result of interactions between components of their microhabitat and macrohabitat. The correlation analysis pointed out the preferences of lichen species to their host trees, especially Quercus and Fraxinus, altitude and tree level variables as are aspect and mosses coverage. The regression analysis has highlighted that the changes in lichen species abundances are caused by macrohabitat level predictors such as host trees represented by Fraxinus. This study demonstrates that, structure of lichen species is influenced by attributes of mixed forest habitats; therefore maintaining the diversity of tree species and ensuring the continuous occurrence of forestry land is necessary for lichen and their habitat conservation.

  16. [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.

  17. Change in atmospheric deposition during last half century and its impact on lichen community structure in Eastern Himalaya.

    Science.gov (United States)

    Bajpai, Rajesh; Mishra, Seema; Dwivedi, Sanjay; Upreti, Dalip Kumar

    2016-08-09

    Climatic fluctuations largely affects species turnover and cause major shifts of terrestrial ecosystem. In the present study the five decade old herbarium specimens of lichens were compared with recent collection from Darjeeling district with respect to elements, PAHs accumulation and carbon isotope composition (δ(13)C) to explore the changes in climatic conditions and its impact on lichen flora. The δ(13)C has increased in recent specimens which is in contrast to the assumption that anthropogenic emission leads to δ(13)C depletion in air and increased carbon discrimination in flora. Study clearly demonstrated an increase in anthropogenic pollution and drastic decrease in precipitation while temperature showed abrupt changes during the past five decades resulting in significant change in lichen community structure. The Usneoid and Pertusorioid communities increased, while Physcioid and Cyanophycean decreased, drastically. Lobarian abolished from the study area, however, Calcicoid has been introduced in the recent past. Probably, post-industrial revolution, the abrupt changes in the environment has influenced CO2 diffusion and/C fixation of (lower) plants either as an adaptation strategy or due to toxicity of pollutants. Thus, the short term studies (≤5 decades) might reflect recent micro-environmental condition and lichen community structure can be used as model to study the global climate change.

  18. Change in atmospheric deposition during last half century and its impact on lichen community structure in Eastern Himalaya

    Science.gov (United States)

    Bajpai, Rajesh; Mishra, Seema; Dwivedi, Sanjay; Upreti, Dalip Kumar

    2016-08-01

    Climatic fluctuations largely affects species turnover and cause major shifts of terrestrial ecosystem. In the present study the five decade old herbarium specimens of lichens were compared with recent collection from Darjeeling district with respect to elements, PAHs accumulation and carbon isotope composition (δ13C) to explore the changes in climatic conditions and its impact on lichen flora. The δ13C has increased in recent specimens which is in contrast to the assumption that anthropogenic emission leads to δ13C depletion in air and increased carbon discrimination in flora. Study clearly demonstrated an increase in anthropogenic pollution and drastic decrease in precipitation while temperature showed abrupt changes during the past five decades resulting in significant change in lichen community structure. The Usneoid and Pertusorioid communities increased, while Physcioid and Cyanophycean decreased, drastically. Lobarian abolished from the study area, however, Calcicoid has been introduced in the recent past. Probably, post-industrial revolution, the abrupt changes in the environment has influenced CO2 diffusion and/C fixation of (lower) plants either as an adaptation strategy or due to toxicity of pollutants. Thus, the short term studies (≤5 decades) might reflect recent micro-environmental condition and lichen community structure can be used as model to study the global climate change.

  19. 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

  20. 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.

  1. 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.

  2. 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.

  3. Distribution and ecology of the lichen Fellhanera gyrophorica in the Pojezierze Olsztyńskie Lakeland and its status in Poland

    Directory of Open Access Journals (Sweden)

    Dariusz Kubiak

    2011-12-01

    Full Text Available The study presents recent data on the distribution of Fellhanera gyrophorica (Pilocarpaceae, Ascomycota in Poland, a rare lichen with a crustose, usually sterile thallus. Both previous and new localities of the species are presented with data on its eco­logy and general distribution. Furthermore, this paper provides detailed results on floristic investigations of the species in the forest areas of the Pojezierze Olsztyńskie Lakeland (Northern Poland. Fertile specimens of F. gyrophorica have been observed in Poland for the second time and in the world – for the third time. Also, a new substrate for this species has been found: Acer platanoides. In addition, Carpinus betulus and Populus tremula were also found to be the species' substrates in Poland. Based on this study and previous reports, F. gyrophorica seems to be a relatively common species in north-eastern Poland.

  4. 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 ...

  5. 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.

  6. Early stage differentiation of thallus cells of Porphyra haitanensis (Rhodophyta)

    Science.gov (United States)

    Wang, Sujuan; Sun, Yunlong; Lu, Anming; Wang, Guangyuan

    1987-09-01

    The early stage differentiation of thallus cells of Porphyra haitanensis T. J. Chang et B. F. Zheng was studied. Protoplasts or single cells were isolated from the blades using enzyme mixture comprising 2% sea snail gut enzyme and 1% cellulase. The isolated protoplasts or single cells were incubated in the MES medium. The cell differentiations were examined under the microscope at intervals after incubation. Four types of cell differentiation, namely, normal, abnormal, carposporangial and spermatorangial, and rhizoidal types, were observed. Since normal cell differentiations occur mostly in small thalli 50 mm in length and middle portions of big thalli 200 mm in length, it is essential to select tissues from these two kinds of thalli essential for commercial production.

  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. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. 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

  15. 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

  16. Probing the molecular and electronic structure of the lichen metabolite usnic acid: A DFT study

    International Nuclear Information System (INIS)

    Galasso, V.

    2010-01-01

    Graphical abstract: DFT calculations of structural preferences, acidic properties, carbonyl vibrations, 13 C NMR chemical shifts, and absorption spectrum account for the unique structural backbone, chemical behaviour, and spectroscopic properties of usnic acid, the cortical pigment and potent reactive of lichens. - Abstract: The molecular structure of usnic acid was investigated by the density functional theory (DFT). Two keto-enol tautomers are nearly isoenergetic and more stable than other tautomers. Noteworthy is the energy difference among the three intramolecular O-H...O hydrogen bonds. The DFT/PCM calculated dissociation constants account for the acidic sequence of the three OH-groups. The electronic structure was also studied by calculating IR/Raman, NMR, and absorption features. A reliable assignment of the 'fingerprint' carbonyl stretching modes was supported by calculations on related molecules. The calculated NMR chemical shifts fit expectation in terms of a fast interconversion between the two most preferred tautomers. A variety of π → π* and n → π* excitations, localized on a single ring or involving a charge-transfer between the two lateral rings of the molecule, gives rise to the broad UV-absorption bands. This property accounts for the efficient protection against damaging solar radiation provided by usnic acid for lichens.

  17. Probing the molecular and electronic structure of the lichen metabolite usnic acid: A DFT study

    Energy Technology Data Exchange (ETDEWEB)

    Galasso, V., E-mail: galasso@univ.trieste.it [Dipartimento di Scienze Chimiche, Universita di Trieste, I-34127 Trieste (Italy)

    2010-08-23

    Graphical abstract: DFT calculations of structural preferences, acidic properties, carbonyl vibrations, {sup 13}C NMR chemical shifts, and absorption spectrum account for the unique structural backbone, chemical behaviour, and spectroscopic properties of usnic acid, the cortical pigment and potent reactive of lichens. - Abstract: The molecular structure of usnic acid was investigated by the density functional theory (DFT). Two keto-enol tautomers are nearly isoenergetic and more stable than other tautomers. Noteworthy is the energy difference among the three intramolecular O-H...O hydrogen bonds. The DFT/PCM calculated dissociation constants account for the acidic sequence of the three OH-groups. The electronic structure was also studied by calculating IR/Raman, NMR, and absorption features. A reliable assignment of the 'fingerprint' carbonyl stretching modes was supported by calculations on related molecules. The calculated NMR chemical shifts fit expectation in terms of a fast interconversion between the two most preferred tautomers. A variety of {pi} {yields} {pi}* and n {yields} {pi}* excitations, localized on a single ring or involving a charge-transfer between the two lateral rings of the molecule, gives rise to the broad UV-absorption bands. This property accounts for the efficient protection against damaging solar radiation provided by usnic acid for lichens.

  18. IDENTIFICATION OF A ROBUST LICHEN INDEX FOR THE DECONVOLUTION OF LICHEN AND ROCK MIXTURES USING PATTERN SEARCH ALGORITHM (CASE STUDY: GREENLAND

    Directory of Open Access Journals (Sweden)

    S. Salehi

    2016-06-01

    Full Text Available Lichens are the dominant autotrophs of polar and subpolar ecosystems commonly encrust the rock outcrops. Spectral mixing of lichens and bare rock can shift diagnostic spectral features of materials of interest thus leading to misinterpretation and false positives if mapping is done based on perfect spectral matching methodologies. Therefore, the ability to distinguish the lichen coverage from rock and decomposing a mixed pixel into a collection of pure reflectance spectra, can improve the applicability of hyperspectral methods for mineral exploration. The objective of this study is to propose a robust lichen index that can be used to estimate lichen coverage, regardless of the mineral composition of the underlying rocks. The performance of three index structures of ratio, normalized ratio and subtraction have been investigated using synthetic linear mixtures of pure rock and lichen spectra with prescribed mixing ratios. Laboratory spectroscopic data are obtained from lichen covered samples collected from Karrat, Liverpool Land, and Sisimiut regions in Greenland. The spectra are then resampled to Hyperspectral Mapper (HyMAP resolution, in order to further investigate the functionality of the indices for the airborne platform. In both resolutions, a Pattern Search (PS algorithm is used to identify the optimal band wavelengths and bandwidths for the lichen index. The results of our band optimization procedure revealed that the ratio between R894-1246 and R1110 explains most of the variability in the hyperspectral data at the original laboratory resolution (R2=0.769. However, the normalized index incorporating R1106-1121 and R904-1251 yields the best results for the HyMAP resolution (R2=0.765.

  19. Distribution patterns of terricolous and saxicolous lichens in extreme desert conditions

    Science.gov (United States)

    Temina, M.

    2012-04-01

    The investigation of biodiversity in stressful habitats is of great interest because it elucidates relationships between organisms and their environment, as well as revealing the mechanisms of their survival and adaptation to extreme conditions. Deserts represent such stressful habitats where harsh climate and limited resources greatly influence the formation of biota. In order to understand the link between microscale environmental variability in extreme arid conditions and lichen biodiversity patterns, we conducted the present study. For this purpose, the structure and distribution of lichen communities on soil and cobbles at six stations at "Evolution Canyon" III (EC III), Nahal Shaharut, in the extreme southern Negev, Israel, were examined. The opposite slopes of the canyon represented specific ecological niches characterized by sharply different microclimatic conditions. The following characteristics of lichen communities were studied: species richness, systematic diversity, biogeographical elements, frequencies and distribution of species, their morphological and anatomical characteristics, reproductive strategy, and ecological peculiarities. In the research site three environmental variables were evaluated: soil moisture, and temperatures of soil and cobbles. The Canonical Correspondence Analysis was used to study the influence of these ecological variables on the distribution of lichen species. The lichen diversity of EC III was very poor and comprised 12 species (3 cyanoliches on soil vs. 9 phycolichens on cobbles). Most of them belong to a specific group of arid endemic elements, adapted to survive in extreme arid conditions in the deserts of the Levant. The harsh desert conditions of the canyon negatively influence the reproductive ability of lichens. This influence is expressed in the decreased sizes of fruit bodies in some species, and the frequent occurrence of sterile specimens among lichens found in the canyon. A comparative analysis of structure

  20. 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.

  1. 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.

  2. 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.…

  3. 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

  4. 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.

  5. 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.

  6. Cold resistance and metabolic activity of lichens below 0 degC

    Science.gov (United States)

    Kappen, L.; Schroeter, B.; Scheidegger, C.; Sommerkorn, M.; Hestmark, G.

    Laboratory measurements show that lichens are extremely tolerant of freezing stress and of low-temperature exposure. Metabolic activity recovered quickly after severe and extended cold treatment. Experimental results demonstrate also that CO_2 exchange is already active at around -20 degC. The psychrophilic character of polar lichen species is demonstrated by optimum temperatures for net photosynthesis between 0 and 15 degC. In situ measurements show that lichens begin photosynthesizing below 0 degC if the dry thalli receive fresh snow. The lowest temperature measured in active lichens was -17 degC at a continental Antarctic site. The fine structure and the hydration state of photobiont and mycobiont cells were studied by low-temperature scanning electron microscopy (LTSEM) of frozen hydrated specimens. Water potentials of the frozen system are in the range of or even higher than those allowing dry lichens to start photosynthesis by water vapor uptake at +10 degC. The great success of lichens in polar and high alpine regions gives evidence of their physiological adaptation to low temperatures. In general lichens are able to persist through glacial periods, but extended snow cover and glaciation are limiting factors.

  7. 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...

  8. 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.

  9. Effects of sulfur dioxide on net CO/sub 2/ assimilation in the lichen Evernia mesomorpha Nyl

    Energy Technology Data Exchange (ETDEWEB)

    Huebert, D B; L' Hirondelle, S J; Addison, P A

    1985-01-01

    Physiologically active thalli of the lichen Evernia mesomorpha Nyl. were very sensitive to short-term fumigations with low concentrations of gaseous sulfur dioxide. Net CO/sub 2/ assimilation rate (NAR) was significantly reduced after exposure to 0.085 ..mu..l l/sup -1/ (250 ..mu..g m/sup -3/) SO/sub 2/ for 1 h or more, and the reduction increased with increasing concentration. Duration of exposure had no significant effect on NAR, indicating the importance of rate of SO/sub 2/ uptake rather than the total amount absorbed. Respiration was significantly reduced after 4 h or more of exposure to 0.265 ..mu..l l/sup -1/ (639 ..mu..g m/sup -3/) SO/sub 2/ or higher. Recovery of NAR after fumigation was dependent on both SO/sub 2/ concentration and duration of fumigation, and on the time allowed for recovery. Virtually complete recovery occurred within 24 h after episodes with up to 0.355 ..mu..l l/sup -1/ (856 ..mu..g m/sup -3/) SO/sub 2/ for 1 h and 0.085 ..mu..l l/sup -1/ SO/sub 2/ for 4 h. Above these levels, recovery was incomplete or nonexistent after 24 h in clean air. The level of sensitivity found can be attributed to the environmental conditions during fumigation, which prevented thallus desiccation and inactivity. Based on this study, neither the concept of dose (concentration x time) nor that of threshold levels of SO/sub 2/ fumigations are supported. Peak exposures to SO/sub 2/ for short periods may be of primary importance in determining the survival of lichens in industrial areas.

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. 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....

  15. Cellular Responses of the Lichen Circinaria gyrosa in Mars-Like Conditions

    Directory of Open Access Journals (Sweden)

    Rosa de la Torre Noetzel

    2018-03-01

    Full Text Available Lichens are extremely resistant organisms that colonize harsh climatic areas, some of them defined as “Mars-analog sites.” There still remain many unsolved questions as to how lichens survive under such extreme conditions. Several studies have been performed to test the resistance of various lichen species under space and in simulated Mars-like conditions. The results led to the proposal that Circinaria gyrosa (Lecanoromycetes, Ascomycota is one of the most durable astrobiological model lichens. However, although C. gyrosa has been exposed to Mars-like environmental conditions while in a latent state, it has not been exposed in its physiologically active mode. We hypothesize that the astrobiological test system “Circinaria gyrosa,” could be able to be physiologically active and to survive under Mars-like conditions in a simulation chamber, based on previous studies performed at dessicated-dormant stage under simulated Mars-like conditions, that showed a complete recover of the PSII activity (Sánchez et al., 2012. Epifluorescence and confocal laser scanning microscopy (CLSM showed that living algal cells were more abundant in samples exposed to niche conditions, which simulated the conditions in micro-fissures and micro-caves close to the surface that have limited scattered or time-dependent light exposure, than in samples exposed to full UV radiation. The medulla was not structurally affected, suggesting that the niche exposure conditions did not disturb the lichen thalli structure and morphology as revealed by field emission scanning electron microscopy (FESEM. In addition, changes in the lichen thalli chemical composition were determined by analytical pyrolysis. The chromatograms resulting from analytical pyrolysis at 500°C revealed that lichen samples exposed to niche conditions and full UV radiation consisted primarily of glycosidic compounds, lipids, and sterols, which are typical constituents of the cell walls. However, specific

  16. Cellular Responses of the Lichen Circinaria gyrosa in Mars-Like Conditions.

    Science.gov (United States)

    de la Torre Noetzel, Rosa; Miller, Ana Z; de la Rosa, José M; Pacelli, Claudia; Onofri, Silvano; García Sancho, Leopoldo; Cubero, Beatriz; Lorek, Andreas; Wolter, David; de Vera, Jean P

    2018-01-01

    Lichens are extremely resistant organisms that colonize harsh climatic areas, some of them defined as "Mars-analog sites." There still remain many unsolved questions as to how lichens survive under such extreme conditions. Several studies have been performed to test the resistance of various lichen species under space and in simulated Mars-like conditions. The results led to the proposal that Circinaria gyrosa (Lecanoromycetes, Ascomycota) is one of the most durable astrobiological model lichens. However, although C . gyrosa has been exposed to Mars-like environmental conditions while in a latent state, it has not been exposed in its physiologically active mode. We hypothesize that the astrobiological test system " Circinaria gyrosa ," could be able to be physiologically active and to survive under Mars-like conditions in a simulation chamber, based on previous studies performed at dessicated-dormant stage under simulated Mars-like conditions, that showed a complete recover of the PSII activity (Sánchez et al., 2012). Epifluorescence and confocal laser scanning microscopy (CLSM) showed that living algal cells were more abundant in samples exposed to niche conditions, which simulated the conditions in micro-fissures and micro-caves close to the surface that have limited scattered or time-dependent light exposure, than in samples exposed to full UV radiation. The medulla was not structurally affected, suggesting that the niche exposure conditions did not disturb the lichen thalli structure and morphology as revealed by field emission scanning electron microscopy (FESEM). In addition, changes in the lichen thalli chemical composition were determined by analytical pyrolysis. The chromatograms resulting from analytical pyrolysis at 500°C revealed that lichen samples exposed to niche conditions and full UV radiation consisted primarily of glycosidic compounds, lipids, and sterols, which are typical constituents of the cell walls. However, specific differences could be

  17. 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...

  18. A Case of Lichen Planus Pigmentosus-Inversus

    Directory of Open Access Journals (Sweden)

    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.

  19. 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.

  20. 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.

  1. Photosynthesis of green algal soil crust lichens from arid lands in southern Utah, USA: Role of water content on light and temperature responses of CO2 exchange

    Science.gov (United States)

    Lange, Otto L.; Belnap, Jayne; Meyer, Angelika

    1997-01-01

    Biotic soil crusts are a worldwide phenomenon in arid and semi-arid landscapes. Metabolic activity of the poikilohydric organisms found in these crusts is dominated by quick and drastic changes in moisture availability and long periods of drought. Under controlled conditions, we studied the role of water content on photosynthetic and respiratory CO2 exchange of three green algal soil crust lichens from a desert site in southern Utah (USA): Diploschistes diacapsis (Ach.) Lumbsch, Psora cerebriformis W. Weber, and Squamarina lentigera (Weber) Poelt.Photosynthetic metabolism is activated by extremely small amounts of moisture; lower compensation values for net photosynthesis (NP) are reached between 0.05 and 0.27 mm of precipitation equivalent. Thus, the lichens can use very low degrees of hydration for carbon gain. Maximal NP occurs between 0.39 and 0.94 mm precipitation equivalent, and area-related rates equal 2.6–5.2 μmol CO2 m−2s−1. All three tested species show ‘sun plant’ features, including high light requirements for CO2 exchange compensation and for NP saturation.Diploschistes diacapsis maintains high rates of NP at full water saturation. In contrast, suprasaturated thalli of the other two species show a strong depression in NP which can be removed or reduced by increased external CO2 concentration. Consequently, this depression is most probably caused by increased thallus diffusive resistances due to pathway blockage by water. This depression will greatly limit carbon gain of these species in the field after heavy rain. It occurs at all temperatures of ecological relevance and also under conditions of low light. However, maximum water holding capacity of P. cerebriformis and S. lentigera is higher than that of D. diacapsis. This could mean that periods of hydration favorable for metabolic activity for those two species last longer than those of D. diacapsis. This might compensate for their lower rates of NP during suprasaturation. Thus, two

  2. 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.

  3. 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.

  4. 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.

  5. 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

  6. Effects of Management on Lichen Species Richness, Ecological Traits and Community Structure in the Rodnei Mountains National Park (Romania).

    Science.gov (United States)

    Ardelean, Ioana Violeta; Keller, Christine; Scheidegger, Christoph

    2015-01-01

    Lichens are valuable bio-indicators for evaluating the consequences of human activities that are increasingly changing the earth's ecosystems. Since a major objective of national parks is the preservation of biodiversity, our aim is to analyse how natural resource management, the availability of lichen substrates and environmental parameters influence lichen diversity in Rodnei Mountains National Park situated in the Eastern Carpathians. Three main types of managed vegetation were investigated: the transhumance systems in alpine meadows, timber exploitation in mixed and pure spruce forests, and the corresponding conserved sites. The data were sampled following a replicated design. For the analysis, we considered not only all lichen species, but also species groups from different substrates such as soil, trees and deadwood. The lichen diversity was described according to species richness, red-list status and substrate-specialist species richness. The variation in species composition was related to the environmental variables. Habitat management was found to negatively influence species richness and alter the lichen community composition, particularly for threatened and substrate-specialist species. It reduced the mean level of threatened species richness by 59%, when all lichen species were considered, and by 81%, when only epiphytic lichens were considered. Management-induced disturbance significantly decreased lichen species richness in forest landscapes with long stand continuity. The diversity patterns of the lichens indicate a loss of species richness and change in species composition in areas where natural resources are still exploited inside the borders of the national park. It is thus imperative for protected areas, in particular old-growth forests and alpine meadows, to receive more protection than they have received in the past to ensure populations of the characteristic species remain viable in the future.

  7. Effects of Management on Lichen Species Richness, Ecological Traits and Community Structure in the Rodnei Mountains National Park (Romania.

    Directory of Open Access Journals (Sweden)

    Ioana Violeta Ardelean

    Full Text Available Lichens are valuable bio-indicators for evaluating the consequences of human activities that are increasingly changing the earth's ecosystems. Since a major objective of national parks is the preservation of biodiversity, our aim is to analyse how natural resource management, the availability of lichen substrates and environmental parameters influence lichen diversity in Rodnei Mountains National Park situated in the Eastern Carpathians. Three main types of managed vegetation were investigated: the transhumance systems in alpine meadows, timber exploitation in mixed and pure spruce forests, and the corresponding conserved sites. The data were sampled following a replicated design. For the analysis, we considered not only all lichen species, but also species groups from different substrates such as soil, trees and deadwood. The lichen diversity was described according to species richness, red-list status and substrate-specialist species richness. The variation in species composition was related to the environmental variables. Habitat management was found to negatively influence species richness and alter the lichen community composition, particularly for threatened and substrate-specialist species. It reduced the mean level of threatened species richness by 59%, when all lichen species were considered, and by 81%, when only epiphytic lichens were considered. Management-induced disturbance significantly decreased lichen species richness in forest landscapes with long stand continuity. The diversity patterns of the lichens indicate a loss of species richness and change in species composition in areas where natural resources are still exploited inside the borders of the national park. It is thus imperative for protected areas, in particular old-growth forests and alpine meadows, to receive more protection than they have received in the past to ensure populations of the characteristic species remain viable in the future.

  8. 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)

  9. 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,...

  10. Non-Destructive Lichen Biomass Estimation in Northwestern Alaska: A Comparison of Methods

    Science.gov (United States)

    Rosso, Abbey; Neitlich, Peter; Smith, Robert J.

    2014-01-01

    Terrestrial lichen biomass is an important indicator of forage availability for caribou in northern regions, and can indicate vegetation shifts due to climate change, air pollution or changes in vascular plant community structure. Techniques for estimating lichen biomass have traditionally required destructive harvesting that is painstaking and impractical, so we developed models to estimate biomass from relatively simple cover and height measurements. We measured cover and height of forage lichens (including single-taxon and multi-taxa “community” samples, n = 144) at 73 sites on the Seward Peninsula of northwestern Alaska, and harvested lichen biomass from the same plots. We assessed biomass-to-volume relationships using zero-intercept regressions, and compared differences among two non-destructive cover estimation methods (ocular vs. point count), among four landcover types in two ecoregions, and among single-taxon vs. multi-taxa samples. Additionally, we explored the feasibility of using lichen height (instead of volume) as a predictor of stand-level biomass. Although lichen taxa exhibited unique biomass and bulk density responses that varied significantly by growth form, we found that single-taxon sampling consistently under-estimated true biomass and was constrained by the need for taxonomic experts. We also found that the point count method provided little to no improvement over ocular methods, despite increased effort. Estimated biomass of lichen-dominated communities (mean lichen cover: 84.9±1.4%) using multi-taxa, ocular methods differed only nominally among landcover types within ecoregions (range: 822 to 1418 g m−2). Height alone was a poor predictor of lichen biomass and should always be weighted by cover abundance. We conclude that the multi-taxa (whole-community) approach, when paired with ocular estimates, is the most reasonable and practical method for estimating lichen biomass at landscape scales in northwest Alaska. PMID:25079228

  11. Non-destructive lichen biomass estimation in northwestern Alaska: a comparison of methods.

    Directory of Open Access Journals (Sweden)

    Abbey Rosso

    Full Text Available Terrestrial lichen biomass is an important indicator of forage availability for caribou in northern regions, and can indicate vegetation shifts due to climate change, air pollution or changes in vascular plant community structure. Techniques for estimating lichen biomass have traditionally required destructive harvesting that is painstaking and impractical, so we developed models to estimate biomass from relatively simple cover and height measurements. We measured cover and height of forage lichens (including single-taxon and multi-taxa "community" samples, n = 144 at 73 sites on the Seward Peninsula of northwestern Alaska, and harvested lichen biomass from the same plots. We assessed biomass-to-volume relationships using zero-intercept regressions, and compared differences among two non-destructive cover estimation methods (ocular vs. point count, among four landcover types in two ecoregions, and among single-taxon vs. multi-taxa samples. Additionally, we explored the feasibility of using lichen height (instead of volume as a predictor of stand-level biomass. Although lichen taxa exhibited unique biomass and bulk density responses that varied significantly by growth form, we found that single-taxon sampling consistently under-estimated true biomass and was constrained by the need for taxonomic experts. We also found that the point count method provided little to no improvement over ocular methods, despite increased effort. Estimated biomass of lichen-dominated communities (mean lichen cover: 84.9±1.4% using multi-taxa, ocular methods differed only nominally among landcover types within ecoregions (range: 822 to 1418 g m-2. Height alone was a poor predictor of lichen biomass and should always be weighted by cover abundance. We conclude that the multi-taxa (whole-community approach, when paired with ocular estimates, is the most reasonable and practical method for estimating lichen biomass at landscape scales in northwest Alaska.

  12. Non-destructive lichen biomass estimation in northwestern Alaska: a comparison of methods.

    Science.gov (United States)

    Rosso, Abbey; Neitlich, Peter; Smith, Robert J

    2014-01-01

    Terrestrial lichen biomass is an important indicator of forage availability for caribou in northern regions, and can indicate vegetation shifts due to climate change, air pollution or changes in vascular plant community structure. Techniques for estimating lichen biomass have traditionally required destructive harvesting that is painstaking and impractical, so we developed models to estimate biomass from relatively simple cover and height measurements. We measured cover and height of forage lichens (including single-taxon and multi-taxa "community" samples, n = 144) at 73 sites on the Seward Peninsula of northwestern Alaska, and harvested lichen biomass from the same plots. We assessed biomass-to-volume relationships using zero-intercept regressions, and compared differences among two non-destructive cover estimation methods (ocular vs. point count), among four landcover types in two ecoregions, and among single-taxon vs. multi-taxa samples. Additionally, we explored the feasibility of using lichen height (instead of volume) as a predictor of stand-level biomass. Although lichen taxa exhibited unique biomass and bulk density responses that varied significantly by growth form, we found that single-taxon sampling consistently under-estimated true biomass and was constrained by the need for taxonomic experts. We also found that the point count method provided little to no improvement over ocular methods, despite increased effort. Estimated biomass of lichen-dominated communities (mean lichen cover: 84.9±1.4%) using multi-taxa, ocular methods differed only nominally among landcover types within ecoregions (range: 822 to 1418 g m-2). Height alone was a poor predictor of lichen biomass and should always be weighted by cover abundance. We conclude that the multi-taxa (whole-community) approach, when paired with ocular estimates, is the most reasonable and practical method for estimating lichen biomass at landscape scales in northwest Alaska.

  13. 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

  14. 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.

  15. 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.

  16. 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

  17. Effects of Streptococcus sanguinis Bacteriocin on Cell Surface Hydrophobicity, Membrane Permeability, and Ultrastructure of Candida Thallus

    Directory of Open Access Journals (Sweden)

    Shengli Ma

    2015-01-01

    Full Text Available Candida albicans (C.a and Candida tropicalis (C.t were treated with Streptococcus sanguinis bacteriocin (S.s bacteriocin, respectively; the bacteriostatic dynamics of S.s bacteriocin, their effects on cell surface hydrophobicity, leakage of inorganic phosphorus and macromolecular substance, cytosolic calcium concentration, and ultrastructure changes of Candida thallus were detected and analyzed. The results showed that inhibitory effect of S.s bacteriocin on C.a and C.t reached peak level at 24 h, the cell-surface hydrophobicity decreased significantly (P < 0.05 after S.s bacteriocin treatment, and there was leakage of cytoplasmic inorganic phosphorus and macromolecular substance from C.a and C.t; cytosolic calcium concentration decreased greatly. After 24 h treatment by S.s bacteriocin, depressive deformity and defect could be found in the cell surface of C.a and C.t; the thallus displayed irregular forms: C.a was shrunken, there was unclear margins abutting upon cell wall and cell membrane, nucleus disappeared, and cytoplasm was inhomogeneous; likewise, C.t was first plasmolysis, and then the cytoplasm was shrunk, the ultrastructure of cell wall and cell membrane was continuously damaged, and the nucleus was karyolysis. It was illustrated that S.s bacteriocin had similar antifungal effect on C.a and C.t; their cell surface hydrophobicity, membrane permeability, and ultrastructure were changed significantly on exposure to S.s bacteriocin.

  18. 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.

  19. 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...

  20. 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.

  1. Deciphering functional diversification within the lichen microbiota by meta-omics.

    Science.gov (United States)

    Cernava, Tomislav; Erlacher, Armin; Aschenbrenner, Ines Aline; Krug, Lisa; Lassek, Christian; Riedel, Katharina; Grube, Martin; Berg, Gabriele

    2017-07-19

    Recent evidence of specific bacterial communities extended the traditional concept of fungal-algal lichen symbioses by a further organismal kingdom. Although functional roles were already assigned to dominant members of the highly diversified microbiota, a substantial fraction of the ubiquitous colonizers remained unexplored. We employed a multi-omics approach to further characterize functional guilds in an unconventional model system. The general community structure of the lichen-associated microbiota was shown to be highly similar irrespective of the employed omics approach. Five highly abundant bacterial orders-Sphingomonadales, Rhodospirillales, Myxococcales, Chthoniobacterales, and Sphingobacteriales-harbor functions that are of substantial importance for the holobiome. Identified functions range from the provision of vitamins and cofactors to the degradation of phenolic compounds like phenylpropanoid, xylenols, and cresols. Functions that facilitate the persistence of Lobaria pulmonaria under unfavorable conditions were present in previously overlooked fractions of the microbiota. So far, unrecognized groups like Chthoniobacterales (Verrucomicrobia) emerged as functional protectors in the lichen microbiome. By combining multi-omics and imaging techniques, we highlight previously overlooked participants in the complex microenvironment of the lichens.

  2. The accumulation of metals in lichens

    Directory of Open Access Journals (Sweden)

    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.

  3. FLORA LICHEN WESTERN MOUNTAINS VRANJE PLACE

    Directory of Open Access Journals (Sweden)

    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.

  4. 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.

  5. 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…

  6. 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.

  7. 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.

  8. 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.

  9. Impact of neighbourhood land-cover in epiphytic lichen diversity: Analysis of multiple factors working at different spatial scales

    Energy Technology Data Exchange (ETDEWEB)

    Pinho, P.; Augusto, S.; Maguas, C. [Universidade de Lisboa, Faculdade de Ciencias, Centro de Ecologia e Biologia Vegetal (CEBV), 1749-016 Lisbon (Portugal); Pereira, M.J.; Soares, A. [Universidade Tecnica de Lisboa, Instituto Superior Tecnico, Centro de Recursos Naturais e Ambiente (CERENA) Av. Rovisco Pais, 1049-001 Lisbon (Portugal); Branquinho, C. [Universidade de Lisboa, Faculdade de Ciencias, Centro de Ecologia e Biologia Vegetal (CEBV), 1749-016 Lisbon (Portugal); Universidade Atlantica, Antiga Fabrica da Polvora de Barcarena, 2745-615 Barcarena (Portugal)], E-mail: cmbranquinho@fc.ul.pt

    2008-01-15

    The objective of this work was to determine the impact of neighbourhood land-cover in epiphytic lichen diversity. We used geostatistics to analyse the spatial structure of lichen-indicators (number of lichen species and Lichen Diversity Value) and correlate them to land-cover considering different distances from the observed data. The results showed that lichen diversity was influenced by different environmental factors that act in the same territory but impact lichens at different distances from the source. The differences in the distance of influence of the several land-cover types seem to be related to the size of pollutants/particles that predominantly are dispersed by each land-cover type. We also showed that a local scale of analysis gives a deeper insight into the understanding of lichen richness and abundance in the region. This work highlighted the importance of a multiple spatial scale of analysis to deeply interpret the relation between lichen diversity and the underling environmental factors. - The interpretation of lichen-biodiversity data was improved by using analysis at different scales.

  10. Impact of neighbourhood land-cover in epiphytic lichen diversity: Analysis of multiple factors working at different spatial scales

    International Nuclear Information System (INIS)

    Pinho, P.; Augusto, S.; Maguas, C.; Pereira, M.J.; Soares, A.; Branquinho, C.

    2008-01-01

    The objective of this work was to determine the impact of neighbourhood land-cover in epiphytic lichen diversity. We used geostatistics to analyse the spatial structure of lichen-indicators (number of lichen species and Lichen Diversity Value) and correlate them to land-cover considering different distances from the observed data. The results showed that lichen diversity was influenced by different environmental factors that act in the same territory but impact lichens at different distances from the source. The differences in the distance of influence of the several land-cover types seem to be related to the size of pollutants/particles that predominantly are dispersed by each land-cover type. We also showed that a local scale of analysis gives a deeper insight into the understanding of lichen richness and abundance in the region. This work highlighted the importance of a multiple spatial scale of analysis to deeply interpret the relation between lichen diversity and the underling environmental factors. - The interpretation of lichen-biodiversity data was improved by using analysis at different scales

  11. 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.

  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. 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.

  14. 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.

  15. 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.

  16. 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

  17. Lichen flora particular features of Degelen mountain massif in location of underground nuclear explosion carrying out

    International Nuclear Information System (INIS)

    Ajdarkhanova, G.S.; Andreeva, E.I.; Tuleubaev, B.A.

    1998-01-01

    The 25 kinds of dominant lichens of the Degelen mountain massif of the former Semipalatinsk test site are studied. It is defined, that complex of ecological factors have influence on spreading of lichen flora ceno-population. Lichens heterogeneousness in ability to radionuclides accumulation is determining of variety its anatomic-morphologic structure and physiological activity as well as physico-chemical properties of soils in places of its inhabited place. It is determined, that lichens are able to exist within limits of exposure dose capacity 18-3000 μR/h and under radioactivity by α-radiation 233-426 Bq/kg, by β-radiation 7000-15000 Bq/kg and Cs 137 150-620 Bq/kg. The largest accumulating ability have Parmelia scortea (570 Bq/kg), Parmelia fraudans (620 Bq/kg), Parmelia cetrata (470 Bq/kg), Parmelia conspersa (340 Bq/kg). Cesium-137 in lichens in 2-8 times higher than maximum permissible dose. Complete relation is showed between lichens and inhabitated substrates created conditions for determination of radiation situation by precise characteristics of lichen flora

  18. 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.

  19. 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.

  20. [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.

  1. 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)

  2. 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

  3. 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.

  4. Zinc concentrations in marine macroalgae and a lichen from western Ireland in relation to phylogenetic grouping, habitat and morphology

    International Nuclear Information System (INIS)

    Stengel, Dagmar B.; Macken, Ailbhe; Morrison, Liam; Morley, Nicholas

    2004-01-01

    Zinc concentrations in 19 species of marine macroalgae and a lichen from western Ireland (Spiddal, Co. Galway) were analysed by atomic absorption spectrophotometry. Algae were collected from a single site but occupied different shore levels and belonged to distinct phylogenetic groupings and to different (previously recognised) morphological groups. Concentrations ranged from 15-115 μg g -1 dry weight. The greatest variation in concentration occurred amongst the red algal species, containing both maximum and minimum concentrations. Zn concentrations in brown and green algae were generally lower than those in red algae. When grouped according to thallus morphology, thin, branched sheets (which consisted mainly of red algae) contained the highest Zn concentrations. In filamentous algae, Zn levels were higher than in thick-leathery or coarsely branched algae. However, all green algal species examined had similar Zn concentrations, despite their different morphologies. In brown algae, the highest Zn levels were detected in mid-shore fucoids (Fucus vesiculosus and Fucus serratus), while thicker, subtidal and low-shore brown algae (Laminaria digitata, Halydris siliquosa) exhibited lower Zn concentrations. The lowest Zn concentrations were detected in high-intertidal species (Fucus spiralis, Pelvetia canaliculata), the only marine lichen examined (Ramalina siliquosa) and a red crustose alga (Corallina officinalis). In all morphological groups, red algal representatives contained relatively higher levels of Zn, the exception being Corallina officinalis. Zn levels in 4 species from a second, estuarine site in Galway Bay exhibited the same relative differences amongst species, but were all consistently higher than in algae from Spiddal. It is concluded that Zn accumulation in macroalgae is closely related to ecological growth strategies, following a functional-form model. However, the phylogenetic origin of species which determines carbohydrate and phenol composition, and

  5. Zinc concentrations in marine macroalgae and a lichen from western Ireland in relation to phylogenetic grouping, habitat and morphology

    Energy Technology Data Exchange (ETDEWEB)

    Stengel, Dagmar B.; Macken, Ailbhe; Morrison, Liam; Morley, Nicholas

    2004-05-01

    Zinc concentrations in 19 species of marine macroalgae and a lichen from western Ireland (Spiddal, Co. Galway) were analysed by atomic absorption spectrophotometry. Algae were collected from a single site but occupied different shore levels and belonged to distinct phylogenetic groupings and to different (previously recognised) morphological groups. Concentrations ranged from 15-115 {mu}g g{sup -1} dry weight. The greatest variation in concentration occurred amongst the red algal species, containing both maximum and minimum concentrations. Zn concentrations in brown and green algae were generally lower than those in red algae. When grouped according to thallus morphology, thin, branched sheets (which consisted mainly of red algae) contained the highest Zn concentrations. In filamentous algae, Zn levels were higher than in thick-leathery or coarsely branched algae. However, all green algal species examined had similar Zn concentrations, despite their different morphologies. In brown algae, the highest Zn levels were detected in mid-shore fucoids (Fucus vesiculosus and Fucus serratus), while thicker, subtidal and low-shore brown algae (Laminaria digitata, Halydris siliquosa) exhibited lower Zn concentrations. The lowest Zn concentrations were detected in high-intertidal species (Fucus spiralis, Pelvetia canaliculata), the only marine lichen examined (Ramalina siliquosa) and a red crustose alga (Corallina officinalis). In all morphological groups, red algal representatives contained relatively higher levels of Zn, the exception being Corallina officinalis. Zn levels in 4 species from a second, estuarine site in Galway Bay exhibited the same relative differences amongst species, but were all consistently higher than in algae from Spiddal. It is concluded that Zn accumulation in macroalgae is closely related to ecological growth strategies, following a functional-form model. However, the phylogenetic origin of species which determines carbohydrate and phenol composition

  6. The adaptive response of lichens to mercury exposure involves changes in the photosynthetic machinery

    International Nuclear Information System (INIS)

    Nicolardi, Valentina; Cai, Giampiero; Parrotta, Luigi; Puglia, Michele; Bianchi, Laura; Bini, Luca; Gaggi, Carlo

    2012-01-01

    Lichens are an excellent model to study the bioaccumulation of heavy metals but limited information is available on the molecular mechanisms occurring during bioaccumulation. We investigated the changes of the lichen proteome during exposure to constant concentrations of mercury. We found that most of changes involves proteins of the photosynthetic pathway, such as the chloroplastic photosystem I reaction center subunit II, the oxygen-evolving protein and the chloroplastic ATP synthase β-subunit. This suggests that photosynthesis is a target of the toxic effects of mercury. These findings are also supported by changes in the content of photosynthetic pigments (chlorophyll a and b, and β-carotene). Alterations to the photosynthetic machinery also reflect on the structure of thylakoid membranes of algal cells. Response of lichens to mercury also involves stress-related proteins (such as Hsp70) but not cytoskeletal proteins. Results suggest that lichens adapt to mercury exposure by changing the metabolic production of energy. - Highlights: ► Lichens exposed to Hg° vapors accumulate this metal irreversibly. ► Hg° interferes with physiological processes of the epiphytic lichen Evernia prunastri. ► Hg° promotes changes in the concentration of photosynthetic pigments. ► Hg° treatment causes changes in the ultrastructure of the photobiont plastids. ► Hg° induces changes in the protein machinery involved in the photosynthesis pathway. - Mercury affects the photosynthetic protein machinery of lichens.

  7. 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.

  8. 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.

  9. Lichens as indicators of fluoride emission from a phosphorus plant, Long Harbour, Newfoundland, Canada

    Energy Technology Data Exchange (ETDEWEB)

    Roberts, B.A.; Thompson, L.K.

    1980-01-01

    Fluoride concentrations in the terrestrial lichens Cladina rangiferina (L.) Harm. and Cladina stellaris (Opiz.) Brodo. were correlated inversely with distance from an industrial plant producing elemental phosphorus at Long Harbour, Nfld., in the direction (NE) of the prevailing wind. The fluoride concentrations ranged from 2830 ppm dry weight in a severely damaged area close to the emission source to 15.5 ppm (dry weight) 12 km NE of the industrial plant. Control samples from unpolluted areas had an average fluoride content of 6.4 ppm dry weight. The minimum observed damage symptoms occurred when these lichens had a fluoride content of 25 ppm dry weight. Damage symptoms included discolouration and structure loss. Discolouration effects were not as pronounced as observed on Abies balsamea (L.) Mill. or on Polytrichum commune (Hedw.) but combined with structure loss allowed the degree of damage to be readily identified in the field. Fluoride concentrations in these terrestrial lichens are compared with levels in soil humus, A. balsamea and some terrestrial bryophytes in four damage zones. The lichen tissue had, on average, twice as much fluoride as occurred in soil humus from the same site and about one half the amount of fluoride found in the terrestrial bryophyte P. commune. The effects of fluoride emissions on the epiphytic lichens Hypogymnia physodes (L.) W. Wats. and Alectoria sarmentosa (Ach.) Ach. in this area are also discussed.

  10. 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.

  11. 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.

  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. 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+

  14. 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

  15. 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

  16. MALIGNANT TRANSFORMATION OF EROSIVE ORAL LICHEN PLANUS

    Directory of Open Access Journals (Sweden)

    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.

  17. 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.

  18. 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...

  19. 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.

  20. 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.

  1. 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

  2. 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 ...

  3. 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

  4. 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.

  5. Advanced Photogrammetry to Assess Lichen Colonization in the Hyper-Arid Namib Desert.

    Science.gov (United States)

    Hinchliffe, Graham; Bollard-Breen, Barbara; Cowan, Don A; Doshi, Ashray; Gillman, Len N; Maggs-Kolling, Gillian; de Los Rios, Asuncion; Pointing, Stephen B

    2017-01-01

    The hyper-arid central region of the Namib Desert is characterized by quartz desert pavement terrain that is devoid of vascular plant covers. In this extreme habitat the only discernible surface covers are epilithic lichens that colonize exposed surfaces of quartz rocks. These lichens are highly susceptible to disturbance and so field surveys have been limited due to concerns about disturbing this unusual desert feature. Here we present findings that illustrate how non-destructive surveys based upon advanced photogrammetry techniques can yield meaningful and novel scientific data on these lichens. We combined 'structure from motion analysis,' computer vision and GIS to create 3-dimensional point clouds from two-dimensional imagery. The data were robust in its application to estimating absolute lichen cover. An orange Stellarangia spp. assemblage had coverage of 22.8% of available substrate, whilst for a black Xanthoparmelia spp. assemblage coverage was markedly lower at 0.6% of available substrate. Hyperspectral signatures for both lichens were distinct in the near-infra red range indicating that Xanthoparmelia spp. was likely under relatively more moisture stress than Stellarangia spp. at the time of sampling, and we postulate that albedo effects may have contributed to this in the black lichen. Further transformation of the data revealed a colonization preference for west-facing quartz surfaces and this coincides with prevailing winds for marine fog that is the major source of moisture in this system. Furthermore, a three-dimensional 'fly through' of the lichen habitat was created to illustrate how the application of computer vision in microbiology has further potential as a research and education tool. We discuss how advanced photogrammetry could be applied in astrobiology using autonomous rovers to add quantitative ecological data for visible surface colonization on the surface of Mars.

  6. Advanced Photogrammetry to Assess Lichen Colonization in the Hyper-Arid Namib Desert

    Directory of Open Access Journals (Sweden)

    Graham Hinchliffe

    2017-10-01

    Full Text Available The hyper-arid central region of the Namib Desert is characterized by quartz desert pavement terrain that is devoid of vascular plant covers. In this extreme habitat the only discernible surface covers are epilithic lichens that colonize exposed surfaces of quartz rocks. These lichens are highly susceptible to disturbance and so field surveys have been limited due to concerns about disturbing this unusual desert feature. Here we present findings that illustrate how non-destructive surveys based upon advanced photogrammetry techniques can yield meaningful and novel scientific data on these lichens. We combined ‘structure from motion analysis,’ computer vision and GIS to create 3-dimensional point clouds from two-dimensional imagery. The data were robust in its application to estimating absolute lichen cover. An orange Stellarangia spp. assemblage had coverage of 22.8% of available substrate, whilst for a black Xanthoparmelia spp. assemblage coverage was markedly lower at 0.6% of available substrate. Hyperspectral signatures for both lichens were distinct in the near-infra red range indicating that Xanthoparmelia spp. was likely under relatively more moisture stress than Stellarangia spp. at the time of sampling, and we postulate that albedo effects may have contributed to this in the black lichen. Further transformation of the data revealed a colonization preference for west-facing quartz surfaces and this coincides with prevailing winds for marine fog that is the major source of moisture in this system. Furthermore, a three-dimensional ‘fly through’ of the lichen habitat was created to illustrate how the application of computer vision in microbiology has further potential as a research and education tool. We discuss how advanced photogrammetry could be applied in astrobiology using autonomous rovers to add quantitative ecological data for visible surface colonization on the surface of Mars.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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.)

  12. 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)

  13. 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.

  14. Metabolic Profiling of Alpine and Ecuadorian Lichens

    Directory of Open Access Journals (Sweden)

    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.

  15. 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.

  16. Epiphytic lichen diversity and biomass in low-elevation forests of the eastern Washington Cascade range, USA.

    Science.gov (United States)

    John F. Lehmkuhl

    2004-01-01

    cover types in the eastern Washington Cascade range. Cover types represented a temperature/moisture and stand structural complexity gradient. Lichen litterfall biomass increased with increasing stand complexity and moisture. Lichen litterfall biomass was 3.42 kg/ha in open pine stands, 7.51 kg/ha in young mixed-species stands, 8.55 kg/ha in mature mixed-species stands...

  17. Structural characterisation of novel lichen heteroglycans by NMR spectroscopy and methylation analysis

    DEFF Research Database (Denmark)

    Omarsdottir, Sesseja; Petersen, Bent O.; Paulsen, Berit Smestad

    2006-01-01

    Two galactofuranomannans, Ths-4 and Ths-5, were isolated from the lichen, Thamnolia vermicularis var. subuliformis, using ethanol fractionation and anion-exchange and size-exclusion chromatography. The average molecular weights of Ths-4 and Ths-5 were estimated to be 19 and 200 kDa, respectively....

  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. 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

  20. 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

  1. Physiological and chemical response of lichens transplanted in and around an industrial area of south Italy: relationship with the lichen diversity.

    Science.gov (United States)

    Paoli, Luca; Pisani, Tommaso; Guttová, Anna; Sardella, Giovanni; Loppi, Stefano

    2011-05-01

    The lichen Evernia prunastri (L.) Ach. has been exposed for 3 months in and around an industrial area of Mediterranean Italy for monitoring physiological (photosynthetic efficiency, membrane lipids peroxidation and cell membrane integrity) and chemical (bioaccumulation of the heavy metals Cr, Ni, Pb, V and Zn) effects and investigate the consistency with the environmental quality status depicted by the diversity of epiphytic lichens (index of lichen diversity (ILD)). The results showed that thalli transplanted close to the industrial area exhibited early stress symptoms, as revealed by the increase in electrical conductivity indicating a damage endured by lichen cell membranes. The electrical conductivity was inversely correlated with the diversity of epiphytic lichens recorded at the same sites. The ILD negatively correlated also with membrane lipid peroxidation and the rate of accumulation of Pb, V and Zn. Reciprocal correlations found among trace elements pinpointed vehicular traffic and metal processing in the industrial area as main sources. The damage endured by cell membranes was the best physiological indicator consistent with the air quality status depicted by the diversity of epiphytic lichens. Copyright © 2010 Elsevier Inc. All rights reserved.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. Multifocal lichen sclerosus. Case report

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    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.

  7. Radioactivity measurements in epiphytic lichens of Uludag Mountain in Western Anatolia

    International Nuclear Information System (INIS)

    Ayseguel Kahraman; Goekay Kaynak; Gizem Akkaya; Orhan Guerler; Sezai Yalcin

    2013-01-01

    Activity concentrations of gross-β, naturally occurring 226 Ra, 232 Th, 210 Pb, 7 Be and anthropogenic 137 Cs in epiphytic lichens collected from Uludag Mountain are presented and discussed with the aim of evaluating potential usability of lichens as a biomonitor. The activity concentrations of gross-β, 137 Cs, 40 K, 226 Ra, 232 Th, 210 Pb and 7 Be in the lichen samples were found to be in the range of 177-707, 4.05-94.26, 86-211, below detection limit (BDL)-19.2, BDL-14.0, 229-872, and 72.1-220.7 Bq kg -1 in dry weight, respectively. 137 Cs content in collected epiphytic lichens was in descending order: Parmelia sulcata > Lobaria pulmonaria > Pseudevernia furfuracea > Usnea filipendula. The best biomonitor for 137 Cs among the lichen species used in this study was determined as Parmelia sulcata. Pearson's correlation coefficient was calculated between 137 Cs and 40 K activity concentrations using a statistical package program (SPSS ver. 17.0) and a negative correlation value (R = -0,323, p = 0,222) was obtained. The highest 226 Ra and 232 Th activity concentrations were found in Bogazova Yaylasi which has a geological structure including granitic rocks. It was found that 137 Cs and 7 Be activity concentrations in species demonstrated an inverse behaviour. The effect of mean annual precipitation and temperature on 7 Be activity concentration was determined using multi regression analysis. Also, correlations between the 137 Cs and 7 Be, and 40 K and 7 Be were investigated. (author)

  8. 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.

  9. 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

  10. Notes on Caloplaca lucifuga (Teloschistales, Ascomycota in Poland

    Directory of Open Access Journals (Sweden)

    Dariusz Kubiak

    2013-12-01

    Full Text Available The current knowledge on the occurrence of Caloplaca lucifuga, a rare lichen with an inconspicuous crustose sorediate thallus, is discussed. Both previous and new localities are presented. The most important data on the ecology and general distribution of the species are given. Diagnostic characters related to the morphology, anatomy and chemistry of C. lucifuga that help to differentiate it from similar species are described.

  11. Dermoscopic findings in extragenital lichen sclerosus

    Directory of Open Access Journals (Sweden)

    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.

  12. 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.

  13. 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...

  14. Photosynthesis in chlorolichens: the influence of the habitat light regime.

    Science.gov (United States)

    Piccotto, Massimo; Tretiach, Mauro

    2010-11-01

    The hypothesis that CO(2) gas exchange and chlorophyll a fluorescence (ChlaF) of lichens vary according to the light regimes of their original habitat, as observed in vascular plants, was tested by analysing the photosynthetic performance of 12 populations of seven dorsoventral, foliose lichens collected from open, south-exposed rocks to densely shaded forests. Light response curves were induced at optimum thallus water content and ChlaF emission curves at the species-specific photon flux at which the quantum yield of CO(2) assimilation is the highest and is saturating the photosynthetic process. Photosynthetic pigments were quantified in crude extracts. The results confirm that the maximum rate of gross photosynthesis is correlated with the chlorophyll content of lichens, which is influenced by light as well as by nitrogen availability. Like leaves, shade tolerant lichens emit more ChlaF than sun-loving ones, whereas the photosynthetic quantum conversion is higher in the latter.

  15. Prevalence of Candida Species in Erosive Oral Lichen Planus

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    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.

  16. Analysis of the distribution of epiphytic lichens on Cedrus libani in Elmali Research Forest (Antalya, Turkey).

    Science.gov (United States)

    Cobanoglu, Gulsah; Sevgi, Orhan

    2009-03-01

    In order to evaluate environmental factors limiting distribution of species, diversity of epiphytic lichens was studied in 34 sites along an altitudinal gradient from 1300 to 1900 m on north-facing and south-facing slopes of Elmali Cedar Research Forest (Antalya province, Turkey) regarding the dispersion of lichens in different tree-diameter classes (0-15 cm, 15-30 cm, 30-45 cm, 45-60 cm and >75 cm). The results showed that the relationship between diameter classes with the number of lichen species was R2=0.6022. The highest number of species was in the diameter class of 30-45 cm. There was a clear relationship between all parameters, diameter, altitude and aspect, with species richness. Changes in the community structure of the epiphytic lichen vegetation were detected along an altitudinal gradient revealing the highest species richness in the highest zone. The elevation affected both the number and the composition of the lichen communities and the relationship between the attitudinal zones with number of lichen species was designated as R2=0.6462. The number of species was higher in the north aspects than in the south aspects in all diameter classes. The species number depending on the altitude was also higher in the north-facing slopes than in the south-facing slopes.

  17. 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.

  18. 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.

  19. 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

  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

    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

  1. 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

  2. Treatment of Lichen Planus with Propranalol

    Directory of Open Access Journals (Sweden)

    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.

  3. 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

  4. 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)

  5. 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.

  6. Caloplaca alstrupii, a new lichen species from Denmark

    DEFF Research Database (Denmark)

    Søchting, Ulrik

    1999-01-01

    Caloplaca alstrupii Søchting is described from an old Platanus in Denmark. The sorediate species has a greyish smooth thallus with very characteristic globose to subglobose blister-like areoles that rupture at maturity exposing pale yellowish green soredia. Apothecia sparse, orange, differing fro...... those of the other species having soralia without anthraquinones....

  7. 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.

  8. Growth of lichens and air pollution in the area of Saarbruecken

    Energy Technology Data Exchange (ETDEWEB)

    Seitz, W

    1972-01-01

    Beside 20 saxicolous and earthy lichens 30 species of lichens growing on tree bark were identified in the town of Saarbruecken. The corticolous lichens Pertusaria coccodes, P. henrici, Rhinodina pyrina and Lepraria candelaris as well as the sulfurous lichen Lechidea lucida were found in the Saarland for the first time. In the explored area there is a desert of lichens (zone V) which is 18 km long and about 4 km wide. Next comes an inner fighting zone where the crustose species Lecanora conizaeoides and Lepraria aeruginosa are dominating. An almost undisturbed epiphytic growth of lichens (zone III to I) is restricted only to a few small refuges mostly of the tops of the surrounding hills. The foliose lichens Parmelia saxatilis and P. subrudecta which were growing well developed in some places of the urban area turned out to be remarkably resistent against SO/sub 2/. The otherwise frequent Hypogymnia physodes could be found only in poor initial stages. The frontier of the desert of lichens is correlating with a middle SO/sub 2/ air pollution of 0.06 to 0.09 mg SO/sub 2//m/sup 3/. After having examined the epiphytic vegetation these physically measured values, however, compared with those of other cities are supposed to be quite higher.

  9. Homocysteine and other cardiovascular risk factors in patients with lichen planus.

    Science.gov (United States)

    Saleh, N; Samir, N; Megahed, H; Farid, E

    2014-11-01

    Chronic inflammation was found to play an important role in the development of cardiovascular risk factors. Homocysteine (Hcy) and fibrinogen have been identified as a major independent risk factor for cardiovascular disease. Lichen planus is assumed to be closely related to dyslipidaemia. Several cytokines involved in lichen planus pathogenesis, could explain its association with dyslipidaemia. Also chronic inflammation with lichen planus has been suggested as a component of the metabolic syndrome. The aim of this study was to detect a panel of cardiovascular risk factors in patients of lichen planus. This study was done on 40 patients of lichen planus and 40 healthy controls. All patients and controls were subjected to clinical examination. Serum levels of homocysteine, fibrinogen and high-sensitive C-reactive protein (hs-CRP) were measured by enzyme-linked immunosorbent assay technique (ELISA). Metabolic syndrome parameters including anthropometric measures, lipid profiles, blood sugar and blood pressure were studied. Patients with lichen planus showed significant association with metabolic syndrome parameters than controls (P lichen planus patients than controls (P lichen planus were found to have higher makers of both metabolic and cardiovascular risk factors in relation to controls most probably due to long standing inflammation. © 2013 European Academy of Dermatology and Venereology.

  10. 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

  11. 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.

  12. 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.

  13. 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.

  14. Spatial Molecular Architecture of the Microbial Community of a Peltigera Lichen

    Science.gov (United States)

    Garg, Neha; Zeng, Yi; Edlund, Anna; Melnik, Alexey V.; Mohimani, Hosein; Gurevich, Alexey; Miao, Vivian; Schiffler, Stefan; Lim, Yan Wei; Luzzatto-Knaan, Tal; Cai, Shengxin; Rohwer, Forest; Pevzner, Pavel A.; Cichewicz, Robert H.; Alexandrov, Theodore

    2016-01-01

    ABSTRACT Microbes are commonly studied as individual species, but they exist as mixed assemblages in nature. At present, we know very little about the spatial organization of the molecules, including natural products that are produced within these microbial networks. Lichens represent a particularly specialized type of symbiotic microbial assemblage in which the component microorganisms exist together. These composite microbial assemblages are typically comprised of several types of microorganisms representing phylogenetically diverse life forms, including fungi, photosymbionts, bacteria, and other microbes. Here, we employed matrix-assisted laser desorption ionization–time of flight (MALDI-TOF) imaging mass spectrometry to characterize the distributions of small molecules within a Peltigera lichen. In order to probe how small molecules are organized and localized within the microbial consortium, analytes were annotated and assigned to their respective producer microorganisms using mass spectrometry-based molecular networking and metagenome sequencing. The spatial analysis of the molecules not only reveals an ordered layering of molecules within the lichen but also supports the compartmentalization of unique functions attributed to various layers. These functions include chemical defense (e.g., antibiotics), light-harvesting functions associated with the cyanobacterial outer layer (e.g., chlorophyll), energy transfer (e.g., sugars) surrounding the sun-exposed cyanobacterial layer, and carbohydrates that may serve a structural or storage function and are observed with higher intensities in the non-sun-exposed areas (e.g., complex carbohydrates). IMPORTANCE Microbial communities have evolved over centuries to live symbiotically. The direct visualization of such communities at the chemical and functional level presents a challenge. Overcoming this challenge may allow one to visualize the spatial distributions of specific molecules involved in symbiosis and to define

  15. 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.

  16. 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…

  17. The contents and distributions of cadmium, mercury, and lead in Usnea antarctica lichens from Solorina Valley, James Ross Island (Antarctica).

    Science.gov (United States)

    Zvěřina, Ondřej; Coufalík, Pavel; Barták, Miloš; Petrov, Michal; Komárek, Josef

    2017-12-11

    Lichens are efficient and cost-effective biomonitors of the environment. Their geographic distribution together with their slow growth rate enable investigation of the deposition patterns of various elements and substances. In this research, levels of cadmium, lead, and mercury in Usnea antarctica lichens in the area of James Ross Island, Antarctica, were investigated. The lichens were microwave-digested, and the metals were determined by means of atomic absorption spectrometry with graphite furnace and a direct mercury analyzer. Median total contents of Cd, Hg, and Pb were 0.04, 0.47, and 1.6 mg/kg in whole lichens, respectively. The bottom-up distributions of these metals in the fruticose lichen thalli were investigated, and it was revealed that the accumulation patterns for mercury and lead were opposite to that for cadmium. The probable reason for this phenomenon may lie in the inner structure of thalli. The total contents of metals were comparable with those published for other unpolluted areas of maritime Antarctica. However, this finding was not expected for mercury, since the sampling locality was close to an area with some of the highest mercury contents published for Antarctic lichens. In short, lichens proved their usability as biological monitors, even in harsh conditions. However, the findings emphasize the need to take into account the distributions of elements both in the environment and in the lichen itself.

  18. 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

  19. 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.

  20. Lichen biogeochemical and spatial dynamics in canopies of Eastern white pine (Pinus strobus)

    Science.gov (United States)

    Laughlin, M. M.; Martin, J.; Olson, E.

    2017-12-01

    Forest canopies have been shown to contain complex ecosystem level processes but much of this work is from the tropics or the charismatic tall trees of Oceana and the Pacific Northwestern US. However, many of the processes can occur in other species of trees that are not as tall, as old, nor as surrounded by biological diversity. Such an occurrence is within the lichen diversity and coverage of Eastern white pines (Pinus strobus) in the Lake States region of the US. We used arborist techniques to scale, survey, and document the lichen abundance in three large and regionally old trees (diameter at breast height 70-80+cm, 30m in height, and 100 to 115 years old). These trees represent the first generation of second growth forests to reclaim the landscape following the massive cutover period in the region from 1880s to the 1910s. We surveyed the stem in framed quadrats in the four cardinal directions at every 2 meters, as well as various branch locations, and used digital photographs and image analysis software to quantify coverage. Lichen coverage ranged from 0% to over 50% and increased with height indicating: (1) possible light limitations or bark suitability limitations near the ground, and (2) that conditions, not time, may be more important for lichen abundance. Lastly, because lichens can fix atmospheric nitrogen and absorb substantial amounts of water, we scaled the coverage of lichen to determine the total nitrogen pool and water holding capacity in the footprint of these large trees. The vertical structure of these large trees helps add to these biogeochemical pools and may be an important consideration for management and restoration efforts aimed at slowing nutrient and water loss from upland forests.

  1. The Conjugates of Phenolic Acids in Lichens of the Order Lecanorales

    Directory of Open Access Journals (Sweden)

    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.

  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 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

  3. 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.

  4. 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.

  5. 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...

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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)

  11. 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.

  12. 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.

  13. 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.

  14. Effects of bryophyte and lichen cover on permafrost soil temperature at large scale

    Directory of Open Access Journals (Sweden)

    P. Porada

    2016-09-01

    Full Text Available Bryophyte and lichen cover on the forest floor at high latitudes exerts an insulating effect on the ground. In this way, the cover decreases mean annual soil temperature and can protect permafrost soil. Climate change, however, may change bryophyte and lichen cover, with effects on the permafrost state and related carbon balance. It is, therefore, crucial to predict how the bryophyte and lichen cover will react to environmental change at the global scale. To date, current global land surface models contain only empirical representations of the bryophyte and lichen cover, which makes it impractical to predict the future state and function of bryophytes and lichens. For this reason, we integrate a process-based model of bryophyte and lichen growth into the global land surface model JSBACH (Jena Scheme for Biosphere–Atmosphere Coupling in Hamburg. The model simulates bryophyte and lichen cover on upland sites. Wetlands are not included. We take into account the dynamic nature of the thermal properties of the bryophyte and lichen cover and their relation to environmental factors. Subsequently, we compare simulations with and without bryophyte and lichen cover to quantify the insulating effect of the organisms on the soil. We find an average cooling effect of the bryophyte and lichen cover of 2.7 K on temperature in the topsoil for the region north of 50° N under the current climate. Locally, a cooling of up to 5.7 K may be reached. Moreover, we show that using a simple, empirical representation of the bryophyte and lichen cover without dynamic properties only results in an average cooling of around 0.5 K. This suggests that (a bryophytes and lichens have a significant impact on soil temperature in high-latitude ecosystems and (b a process-based description of their thermal properties is necessary for a realistic representation of the cooling effect. The advanced land surface scheme, including a dynamic bryophyte and lichen model, will

  15. Frontal fibrosing alopecia and lichen planus pigmentosus: diagnosis and therapeutic challenge.

    Science.gov (United States)

    Mulinari-Brenner, Fabiane Andrade; Guilherme, Marina Riedi; Peretti, Murilo Calvo; Werner, Betina

    2017-01-01

    Frontal fibrosing alopecia is a variant of lichen planopilaris with marginal progressive hair loss on the scalp, eyebrows and axillae. We report a case of frontal fibrosing alopecia and lichen planus pigmentosus in a postmenopausal woman, that started with alopecia on the eyebrows and then on the frontoparietal region, with periocular and cervical hyperpigmentation of difficult management. The condition was controlled with systemic corticosteroid therapy and finasteride. Lichen planus pigmentosus is an uncommon variant of lichen planus frequently associated with frontal fibrosing alopecia in darker phototipes. It should be considered in patients affected by scarring alopecia with a pattern of lichen planopilaris and areas of skin hyperpigmentation revealing perifollicular hyperpigmentation refractory to multiple treatments. This case illustrates diagnostic and therapeutic challenge in face of scarring alopecia and perifollicular hyperpigmentation.

  16. 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.

  17. 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

  18. 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 ...

  19. 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.

  20. 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...

  1. Expression of cdk4 and p16 in Oral Lichen Planus.

    Science.gov (United States)

    Goel, Sinny; Khurana, Nita; Marwah, Akanksha; Gupta, Sunita

    2015-01-01

    The purpose of this study was to evaluate the expression of cdk4 and p16, the proteins implicated in hyperproliferation and arrest in oral lichen planus and to compare their expression in erosive and non-erosive oral lichen planus and with normal mucosa and oral squamous cell carcinoma. Analysis of cdk4 and p16 expression was done in 43 erosive oral lichen planus (EOLP) and 17 non-erosive oral lichen planus (NOLP) cases, 10 normal mucosa and 10 oral squamous cell carcinoma (OSCC) cases with immunohistochemistry. This study demonstrated a significantly increased expression of cytoplasmic cdk4 (80% cases, cells stained - 19.6%), and cytoplasmic p16 (68.3% cases, cells stained - 16.4%) in oral lichen planus (OLP) compared to normal mucosa. cdk4 was much higher in OSCC in both cytoplasm and nuclei compared to normal mucosa. Also, while comparing OLP with positive control, significant difference was noted for cdk4 and p16, with expression being more in OSCC. While comparing EOLP with NOLP; significant differences were seen for cdk4 cytoplasmic staining only, for number of cases with positive staining as well as number of cells stained. Overexpression of cytoplasmic cdk4 and p16 was registered in oral lichen planus, however considerably lower than in squamous cell carcinoma. Erosive oral lichen planus demonstrated overexpression of cytoplasmic cdk4 and premalignant nature compared to non-erosive lesion. Therefore there is an obvious possibility for cytoplasmic expression of cdk4 and p16 to predict malignant potential of oral lichen planus lesions.

  2. 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.

  3. Number of nuclei, mitotic activity and cell length in Cladophora sp thallus treated with cadmium and chromium

    Directory of Open Access Journals (Sweden)

    Monika Krajewska

    2014-01-01

    Full Text Available Cladophora sp., a fresh water, filamentous, multi-nucleate alga growing 16 days in the presence of cadmium and chromium at concentrations 10-4 10-8M was the subject of the experiment. Chromium ions reduced the number of nuclei and mitotic activity, and disturbed the correlation between cell length and number of nuclei, more than cadmium ions. Moreover, both tested metals caused the disappearance of cells with numerous nuclei with time of the culture. Only during the first (1-4 days of culture for both metals the concentration of 10-4M and especially of 10-8M increased the number of nuclei, mitotic index and the length of cells. Apical cells were more sensitive to metals than other thallus cells.

  4. 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.

  5. The Relationship between Anger Expression and Its Indices and Oral Lichen Planus.

    Science.gov (United States)

    Mehdipour, Masoumeh; Taghavi Zenouz, Ali; Farnam, Alireza; Attaran, Rana; Farhang, Sara; Safarnavadeh, Maryam; Gholizadeh, Narges; Azari-Marhabi, Saranaz

    2016-05-01

    Oral lichen planus (OLP) is a common inflammatory disease with unknown etiology. Depression, stress and anxiety are psychological factors that their influence on the expression of lichen planus by affecting the immune system's function has been confirmed. There is a probable relationship between anger and OLP expression. Therefore, the present study aimed to evaluate the association of "anger" and OLP. In this descriptive study 95 subjects were included in 3 groups. A: patients with oral lichen planus, B: positive control, C: negative control. Anger and its indices were assessed by the State-Trait Anger Expression Inventory-2 (STAXI-2) questionnaire, and pain was measured via the Visual Analogue Scale (VAS). The collected data were analyzed statistically using SPSS 18 software. The lichen planus and positive control groups bore higher total anger index (AX index) values compared with the negative control. Comparing anger expression-in (AXI) among the lichen planus and negative control groups revealed higher grades in lichen planus group. Evaluating the pain severity index (VAS) data and anger indices in lichen planus group, Spearman's Rank Correlation Test revealed a significant correlation between TAngR (reactional anger traits) and pain severity. The findings of this study indicated that there was a significant correlation between anger control and suppression of lichen planus development. On the other hand, the patients with more severe pain mostly expressed their anger physically. Based on the findings, we can make the claim that anger suppression and its control-in (gathering tension) may play a role in the development of lichen planus as a known psychosomatic disorders.

  6. 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.

  7. 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. .

  8. Investigation of environmental contamination in lichens of Goekceada (Imbroz) Island in Turkey

    International Nuclear Information System (INIS)

    Kahraman, A.; Kaynak, G.; Gurler, O.; Yalcin, S.; Ozturk, S.; Gundogdu, O.

    2009-01-01

    The main objective of the present study is to determine the type of environmental contamination in lichens in Goekceada Island in the Northern Aegean Sea in Turkey. We used two different lichen species Cladonia foliacea and Ramalina pollinaria. In the first part of the investigation, the beta activities of lichens have been measured by using a TENNELEC LB 1000-PW detector. The range of beta activity values was between 607 ± 30 and 308 ± 12 Bq/kg for C. foliacea lichens collected from around Tuz Lake and values for R. pollinaria lichens were found to be 740 ± 25 and 541 ± 17 Bq/kg. The second part of the study was concerned with the gamma spectra of the lichen samples measured by using HpGe detector. 137 Cs, 134 Cs, 40 K, 232 Th, 226 Ra radionuclides were found in C. foliacea collected from around Tepekoey and in R. pollinaria from around Tuz Lake. When these two types of lichens were compared, it was found that R. pollinaria contain more radionuclides. In order to compare and determine which of these lichens act as a better bioaccumulator, K, Mn, Zn, Rb, Sr, Ba and Pb metal content were determined by using Energy Dispersive X-ray fluorescence spectrometry. It was found that C. foliacea collected more Mn and Sr when compared to R. pollinaria.

  9. Investigation of environmental contamination in lichens of Goekceada (Imbroz) Island in Turkey

    Energy Technology Data Exchange (ETDEWEB)

    Kahraman, A.; Kaynak, G. [Physics Department, Faculty of Arts and Sciences, Uludag University, Gorukle Campus, 16059 Bursa (Turkey); Gurler, O. [Physics Department, Faculty of Arts and Sciences, Uludag University, Gorukle Campus, 16059 Bursa (Turkey)], E-mail: ogurler@uludag.edu.tr; Yalcin, S. [Kastamonu University, Education Faculty, 37200 Kastamonu (Turkey); Ozturk, S. [Biology Department, Faculty of Arts and Sciences, Uludag University, Gorukle Campus, 16059 Bursa (Turkey); Gundogdu, O. [CNRP, Department of Physics, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford GU2 7XH (United Kingdom); University of Kocaeli, Umuttepe Campus, 41100, Kocaeli (Turkey)

    2009-02-15

    The main objective of the present study is to determine the type of environmental contamination in lichens in Goekceada Island in the Northern Aegean Sea in Turkey. We used two different lichen species Cladonia foliacea and Ramalina pollinaria. In the first part of the investigation, the beta activities of lichens have been measured by using a TENNELEC LB 1000-PW detector. The range of beta activity values was between 607 {+-} 30 and 308 {+-} 12 Bq/kg for C. foliacea lichens collected from around Tuz Lake and values for R. pollinaria lichens were found to be 740 {+-} 25 and 541 {+-} 17 Bq/kg. The second part of the study was concerned with the gamma spectra of the lichen samples measured by using HpGe detector. {sup 137}Cs, {sup 134}Cs, {sup 40}K, {sup 232}Th, {sup 226}Ra radionuclides were found in C. foliacea collected from around Tepekoey and in R. pollinaria from around Tuz Lake. When these two types of lichens were compared, it was found that R. pollinaria contain more radionuclides. In order to compare and determine which of these lichens act as a better bioaccumulator, K, Mn, Zn, Rb, Sr, Ba and Pb metal content were determined by using Energy Dispersive X-ray fluorescence spectrometry. It was found that C. foliacea collected more Mn and Sr when compared to R. pollinaria.

  10. 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...

  11. [History of Polish botanical and mycological researches on sheets of land of Antarctic and Sub-Antarctic in the years 1977-2009].

    Science.gov (United States)

    Köhler, Piotr; Olech, Maria

    2011-01-01

    The work includes a description of the period from the moment of setting up Polish Polar Station on King George Island (1977) to the end of International Polar Year IV in 2009. Researches on flower plants focused, among others, on plants' morphology, morphological composition of the pollen and anatomical ultra-structure of the leaves. There were also carried out biochemical and other searches for the internal mutability. Within physiological studies one concentrated on the problem of reaction to temperature stress. Biological researches focused mainly on solving taxonomic and bio-geographic problems. Finally, were published several monographs and, among others, the first in history complete description of moss' flora of the whole of Antarctic (2008). Research works over algae included also such issues as floristics, bio-geography, taxonomy and ecology (for instance, the rookery's impact on distribution of algae, or the influence of inanimate factors on dynamics of condensing the Diatoma in different water and soil-bound tanks). Up till now, within mycological investigations has been identified a variety of lichen fungi that for the most part of Antarctic are a novelty. There were scientifically described new for science genera and species of Western Antarctic. Lichenological studies were made in the field of taxonomy, geography, lichenometry, biochemistry of lichens, lichenoindication, ecophysiology and from the point of analysis of base metals' content. There were also described new for science species. Since 1991, were published the results of searches for the base metals' content and vestigial chemical elements in lichens' thallus. Ecophysiological researches concerned both micro-climatic conditions' impact on primary production and lichens' adaptation to a very cold climate. One discovered a mechanism of two-phase hydratization/dehydratization of lichens' thallus. On the ground of palaeobotanical analyzes was reconstructed a development of flora in Western

  12. 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.

  13. 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

  14. Evaluation of Antifungal Potentials and Antioxidant Capacities of Some Foliose Lichen Species

    Directory of Open Access Journals (Sweden)

    Bahar BİLGİN SÖKMEN

    2018-03-01

    Full Text Available This work is aimed to assess of antioxidant and antifungal potential of the foliose lichen species: Flavoparmelia caperata, Xanthoparmelia stenophylla and Xanthoparmelia conspersa. The antifungal activity of lichens were studied against some pathogenic fungi by disc diffusion method. The acetonitrile extracts of these lichens were obtained with Soxhlet extraction. While F. caperata exhibited maximum antifungal activity (32 mm against the C. albicans, the minimum antifungal activity (10 mm was obtained from X. stenophylla lichen against S. cerevisiae. In CUPRAC assay, absorbance values was in order of BHT>X. conspersa>F. caperata>X. stenophylla. As a result of the study, it was concluded that these lichen species may be a potential source for the development of new antifungal and antioxidant compounds.

  15. 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)

  16. 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.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2001-07-01

    The present report summarizes tow time periods of study: 1) August 1997 - April 1998, 2) May 1999 - November 1999. 1) In August 1997 thalli of the lichen Ramalina maciformis (Del.) Bory were collected in the Negev Desert and transplanted with their substrate, flintstones, to 24 biomonitoring sites in the Negev Desert. In April 1998 the lichens were retrieved and their elemental content was determined by ICP-AES. In addition, we examined physiological parameters as presented in report no.1. 2) In May 1999 thalli of the lichen were collected in the control site and transferred together with the substrate to 10 biomonitoring sites in the Negev. These thalli were retrieved in November 1999. We examined: a) the electric conductivity, indicative of cell membrane integrity; b) the production of ethylene indicative of stress; c) the chloropkyll a fluorescence as a means to monitor aspects of photosystem II (PSII) activities in the lichen. Final results of the first period experiment show that lichens exposed to air contaminants at a site of toxic waste deposition, accumulated large amounts of Al, Ba, Ca, Cu, Fe, Mg, Na, Pb, S, Sr and Zn. Preliminary results of the second period of exposure show that physiological parameters, indicative of lichen-viability, detected stress in thalli retrieved from sites in and around the Ramat Hovav Industrial Area in the Negev. (author)

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

    International Nuclear Information System (INIS)

    Garty, Jacob

    2001-01-01

    The present report summarizes tow time periods of study: 1) August 1997 - April 1998, 2) May 1999 - November 1999. 1) In August 1997 thalli of the lichen Ramalina maciformis (Del.) Bory were collected in the Negev Desert and transplanted with their substrate, flintstones, to 24 biomonitoring sites in the Negev Desert. In April 1998 the lichens were retrieved and their elemental content was determined by ICP-AES. In addition, we examined physiological parameters as presented in report no.1. 2) In May 1999 thalli of the lichen were collected in the control site and transferred together with the substrate to 10 biomonitoring sites in the Negev. These thalli were retrieved in November 1999. We examined: a) the electric conductivity, indicative of cell membrane integrity; b) the production of ethylene indicative of stress; c) the chloropkyll a fluorescence as a means to monitor aspects of photosystem II (PSII) activities in the lichen. Final results of the first period experiment show that lichens exposed to air contaminants at a site of toxic waste deposition, accumulated large amounts of Al, Ba, Ca, Cu, Fe, Mg, Na, Pb, S, Sr and Zn. Preliminary results of the second period of exposure show that physiological parameters, indicative of lichen-viability, detected stress in thalli retrieved from sites in and around the Ramat Hovav Industrial Area in the Negev. (author)

  19. 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

  20. 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)

  1. 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.

  2. Antioxidant potential of lichen species and their secondary metabolites. A systematic review.

    Science.gov (United States)

    Fernández-Moriano, Carlos; Gómez-Serranillos, María Pilar; Crespo, Ana

    2016-01-01

    Pharmacological interest of lichens lies in their capacity to produce bioactive secondary metabolites, being most of them phenolic compounds with reactive hydroxyl groups that confer antioxidant potential through various mechanisms. Increasing incidence and impact of oxidative stress-related diseases (i.e., neurodegenerative disorders) has encouraged the search of new pharmacological strategies to face them. Lichens appear to be a promising source of phenolic compounds in the discovery of natural products exerting antioxidant activity. The present review thoroughly discusses the available knowledge on antioxidant properties of lichens, including both in vitro and in vivo studies and the parameters assessed so far on lichen constituents. Literature survey was performed by using as main databases PubMed, Google Scholar, Scopus, Science Direct, and Recent Literature on Lichens. We reviewed 98 highlighted research articles without date restriction. Current report collects data related to antioxidant activities of more than 75 lichen species (from 18 botanical families) and 65 isolated metabolites. Much information comes from in vitro investigations, such as chemical assays evaluating radical scavenging properties, lipid peroxidation inhibition, and reducing power of lichen species and compounds; similarly, research on cellular substrates and animal models generally measures antioxidant enzymes levels and other antioxidant markers, such as glutathione levels or tissue peroxidation. Since consistent evidence demonstrated the contribution of oxidative stress on the development and progression of several human diseases, reviewed data suggest that some lichen compounds are worthy of further investigation and better understanding of their antioxidant and neuroprotective potentials.

  3. 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.

  4. Influence of small towns on the lichen vegetation. Part VII. Discussion and general conclusions

    Energy Technology Data Exchange (ETDEWEB)

    Rydzak, J

    1958-01-01

    The problem of poverty of lichen vegetation in large or industrial towns was raised in 1866. Since then several large European cities have been studied and there were described zones of gradual impoverishment of lichen flora from the outskirts to the centre of the town. The zones are: (1) Zone of normally developed flora at the outskirts of the town. (2) Struggle zone which is a more or less extensive area with scattered houses and which surrounds the crowded central quarters. In this zone scanty specimens of a few lichen species were found; their thalli were contracted, under-developed, as if fighting for life in unfavorable environmental conditions. (3) Lichen-free zone, lichen desert, which comprises the centre of the town and its industrial quarters; no lichens could be found there. The results of these investigations strengthened the belief that lichens are organisms very sensitive to the action of substances formed during coal combustion in town. Sulphur dioxide (SO/sub 2/) was believed to be especially harmful to lichens, causing their death even in trace concentrations.

  5. Deposition of gamma emitters from Chernobyl accident and their transfer in lichen-soil columns.

    Science.gov (United States)

    Lehto, Jukka; Paatero, Jussi; Pehrman, Reijo; Kulmala, Seija; Suksi, Juhani; Koivula, Teija; Jaakkola, Timo

    2008-10-01

    Lichen-soil column samples were taken from several locations in the Southern Finland between 1986 and 2006. Columns were divided into three parts, upper lichen, lower lichen and underlying soil, and their gamma emitting radionuclides, 134Cs, 137Cs, 103Ru, 95Zr, 106Ru, 110mAg, 125Sb and 144Ce, were measured with gamma spectrometry. Deposition values were calculated as Bq/m2 for each sampling site. Distribution of various radionuclides in the three compartments as a function of time was determined. Both effective and ecological half-lives of all radionuclides were calculated for upper lichen, whole lichen and whole lichen-soil column. A linear relation was derived between the physical half-lives and effective half-lives for whole lichen and for whole lichen-soil column. Reindeer meat activity concentrations of various radionuclides and ensuing radiation doses to reindeer-herding people were also estimated for a hypothetical case where a similar high radioactive pollution, as was taken place in the Southern Finland, would have occurred in the reindeer-herding areas in the Finnish Lapland.

  6. Fire, grazing history, lichen abundance, and winter distribution of caribou in Alaska's taiga

    Science.gov (United States)

    Collins, William B.; Dale, Bruce W.; Adams, Layne G.; McElwain, Darien E.; Joly, Kyle

    2011-01-01

    In the early 1990s the Nelchina Caribou (Rangifer tarandus) Herd (NCH) began a dramatic shift to its current winter range, migrating at least an additional 100 km beyond its historic range. We evaluated the impacts of fire and grazing history on lichen abundance and subsequent use and distribution by the NCH. Historic (prior to 1990) and current (2002) winter ranges of the NCH had similar vascular vegetation, lichen cover (P = 0.491), and fire histories (P = 0.535), but the former range had significantly less forage lichen biomass as a result of grazing by caribou. Biomass of forage lichens was twice as great overall (P = 0.031) and 4 times greater in caribou selected sites on the current range than in the historic range, greatly increasing availability to caribou. Caribou on the current range selected for stands with >20% lichen cover (P lichen biomass and stands older than 80 yr postfire (P lichen cover and biomass seldom recovered sufficiently to attract caribou grazing until after ≥60 yr, and, as a group, primary forage lichen species did not reach maximum abundance until 180 yr postfire. Recovery following overgrazing can occur much more quickly because lichen cover, albeit mostly fragments, and organic substrates remain present. Our results provide benchmarks for wildlife managers assessing condition of caribou winter range and predicting effects of fires on lichen abundance and caribou distribution. Of our measurements of cover and biomass by species, densities and heights of trees, elevation, slope and aspect, only percentage cover by Cladonia amaurocraea, Cladina rangiferina, Flavocetraria cuculata, and lowbush cranberry (Vaccinium vitis‐idaea) were necessary for predicting caribou use of winter range.

  7. 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.

  8. 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.

  9. 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.

  10. Responses of lichen communities to 18 years of natural and experimental warming.

    Science.gov (United States)

    Alatalo, Juha M; Jägerbrand, Annika K; Chen, Shengbin; Molau, Ulf

    2017-07-01

    Climate change is expected to have major impacts on high alpine and arctic ecosystems in the future, but empirical data on the impact of long-term warming on lichen diversity and richness are sparse. This study report the effects of 18 years of ambient and experimental warming on lichens and vascular plant cover in two alpine plant communities, a dry heath with sparse canopy cover (54 %) and a mesic meadow with a more developed (67 %) canopy cover, in sub-arctic Sweden. The effects of long-term passive experimental warming using open top chambers (OTCs) on lichens and total vascular plant cover, and the impact of plant cover on lichen community parameters, were analysed. Between 1993 and 2013, mean annual temperature increased about 2 °C. Both site and experimental warming had a significant effect on cover, species richness, effective number of species evenness of lichens, and total plant canopy cover. Lichen cover increased in the heath under ambient conditions, and remained more stable under experimental warming. The negative effect on species richness and effective number of species was driven by a decrease in lichens under experimental warming in the meadow. Lichen cover, species richness, effective number of species evenness were negatively correlated with plant canopy cover. There was a significant negative impact on one species and a non-significant tendency of lower abundance of the most common species in response to experimental warming. The results from the long-term warming study imply that arctic and high alpine lichen communities are likely to be negatively affected by climate change and an increase in plant canopy cover. Both biotic and abiotic factors are thus important for future impacts of climate change on lichens. © The Author 2017. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com

  11. 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.

  12. [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.

  13. Ecological half-life of 137Cs in lichens in an alpine region.

    Science.gov (United States)

    Machart, Peter; Hofmann, Werner; Türk, Roman; Steger, Ferdinand

    2007-01-01

    About 17 years after the Chernobyl accident, lichen samples were collected in an alpine region in Austria (Bad Gastein), which was heavily contaminated by the Chernobyl fallout. Measured 137Cs activity concentrations in selected lichens (Cetraria islandica, Cetraria cucullata, and Cladonia arbuscula) ranged from 100 to 1100 Bq kg(-1) dry weight, depending on lichen species and sampling site. Ecological half-lives for 137Cs in different lichen samples, obtained by comparison with earlier measurements of the same lichen species at the same site, ranged from 2 to 6 years, with average values between 3 and 4 years. Comparison with earlier studies indicated that ecological half-lives hardly changed during the last 10 years, suggesting that ecological clearance mechanisms (e.g. washout or soil transfer) did not vary substantially at the selected sampling area.

  14. Ecological half-life of 137Cs in lichens in an alpine region

    International Nuclear Information System (INIS)

    Machart, Peter; Hofmann, Werner; Tuerk, Roman; Steger, Ferdinand

    2007-01-01

    About 17 years after the Chernobyl accident, lichen samples were collected in an alpine region in Austria (Bad Gastein), which was heavily contaminated by the Chernobyl fallout. Measured 137 Cs activity concentrations in selected lichens (Cetraria islandica, Cetraria cucullata, and Cladonia arbuscula) ranged from 100 to 1100 Bq kg -1 dry weight, depending on lichen species and sampling site. Ecological half-lives for 137 Cs in different lichen samples, obtained by comparison with earlier measurements of the same lichen species at the same site, ranged from 2 to 6 years, with average values between 3 and 4 years. Comparison with earlier studies indicated that ecological half-lives hardly changed during the last 10 years, suggesting that ecological clearance mechanisms (e.g. washout or soil transfer) did not vary substantially at the selected sampling area

  15. Evaluation of serum Malondialdehyde level in patients with oral lichen planus

    Directory of Open Access Journals (Sweden)

    Masoumeh Mehdipour

    2017-03-01

    Full Text Available Introduction: Malondialdehyde (MDA is a useful determinant to show high level of lipid peroxidation which lead to impaired cell function. Previous studies have mentioned there is a relationship between high oxidative stress and low anti-oxidant activity in patients with oral lichen planus. The aim of this study was to evaluate serum level of Malondialdehyde as an indicator of oxidative stress in patients with oral lichen planus which is a chronic inflammatory disease with unknown etiology. Materials & Methods: This descriptive-comparative study evaluated the oxidative stress status on twenty patients with oral lichen planus and 20 control healthy individuals based on serum level of Malondialdehyde. Results: The mean serum Malondialdehyde levels in oral lichen planus patients and control individuals were 2.9 (±2 and 2.4 (±1.3 µg/ml, respectively, indicating no significant difference (P=0.6. Conclusion: According to the results, role of Malondialdehyde in cellular damage and pathogenesis of oral lichen planus was not proved.

  16. 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.

  17. Determination of trace elements in lichen samples by neutron activation analysis

    International Nuclear Information System (INIS)

    Saiki, Mitiko; Coccaro, D.M.B.; Vasconcellos, M.B.A.; Marcelli, M.P.

    1999-01-01

    Epiphytic lichens have been used as bioindicators of environmental pollution studies because of their ability to accumulate metals present in the atmosphere at very low concentrations. In this work, experimental conditions for collection and preparation of the lichen samples as well as the experimental procedure for neutron activation analysis were established in order to obtain reliable and useful data for environmental monitoring purposes. Lichen samples were collected from the barks of trees. They were first examined in a stereo microscope, cleaned and then they were washed with water, freeze-dried and ground for analysis. Out of the five species Usnea sp, Parmotrena tinctorum, Canoparmelia caroliniana, Parmotrema sanctiangeli and Canoparmelia texana analysed, the latter was chosen for this work since this species is very abundant on the Brazilian territory except for the coast. The samples and synthetic standards of elements were irradiated at the IEA-R1 nuclear reactor and the concentrations of the elements Al, As, Br, Ca, Cd, Cl, Co, Cr, Cs, Fe, K, lanthanides, Mg, Mn, Na, Rb, Sb, Sc, Se, Th, U, V and Zn were determined by using short and long irradiations. Results obtained in the washed and unwashed lichen samples showed that the cleaning with water can be used in order to eliminate adhering materials. Indeed, most of elements of interest for the environmental contamination accumulated by the lichens were not removed. The study of the influence of the age of the lichen indicated that its elemental concentrations increase with its age or with the length of exposure. Results obtained for lichens collected from four different trees in the same sampling area varied from about 3.4 to 50%. The homogeneity of the sample was checked by analyzing replicates. The precision and the accuracy of the method were evaluated by analyzing IAEA 336 Lichen and NIST 1752 Citrus Leaves. (author)

  18. Uptake and biotransformation of arsenate in the lichen Hypogymnia physodes (L.) Nyl

    Energy Technology Data Exchange (ETDEWEB)

    Mrak, Tanja [Department of Environmental Sciences, Jozef Stefan Institute, Jamova 39, 1000 Ljubljana (Slovenia); Slejkovec, Zdenka [Department of Environmental Sciences, Jozef Stefan Institute, Jamova 39, 1000 Ljubljana (Slovenia)], E-mail: zdenka.slejkovec@ijs.si; Jeran, Zvonka; Jacimovic, Radojko [Department of Environmental Sciences, Jozef Stefan Institute, Jamova 39, 1000 Ljubljana (Slovenia); Kastelec, Damijana [Agronomy Department, Biotechnical Faculty, University of Ljubljana, Jamnikarjeva 101, 1000 Ljubljana (Slovenia)

    2008-01-15

    The uptake and metabolism of arsenate, As(V), as a function of time and concentration were examined in the lichen Hypogymnia physodes (L.) Nyl. Lichen thalli were exposed to As(V) in the form of a solution. Exponential uptake of As(V) from 4 {mu}g mL{sup -1} As(V) solution was accompanied by constant arsenite, As(III), excretion back into the solution. Arsenate taken up into the lichens from 0, 0.1, 1, 10 {mu}g mL{sup -1} As(V) solutions was partially transformed into As(III), dimethylarsinic acid (DMA) and (mono)methylarsonic acid (MA). 48 h after exposure, the main arsenic compound in the lichens was DMA in 0.1, As(III) in 1 and As(V) in 10 {mu}g mL{sup -1} treatment. The proportion of methylated arsenic compounds decreased with increasing arsenate concentration in the exposure solution. These results suggest that at least two types of As(V) detoxification exist in lichens; arsenite excretion and methylation. - Lichens are able to metabolize the inorganic arsenic taken up.

  19. Uptake and biotransformation of arsenate in the lichen Hypogymnia physodes (L.) Nyl

    International Nuclear Information System (INIS)

    Mrak, Tanja; Slejkovec, Zdenka; Jeran, Zvonka; Jacimovic, Radojko; Kastelec, Damijana

    2008-01-01

    The uptake and metabolism of arsenate, As(V), as a function of time and concentration were examined in the lichen Hypogymnia physodes (L.) Nyl. Lichen thalli were exposed to As(V) in the form of a solution. Exponential uptake of As(V) from 4 μg mL -1 As(V) solution was accompanied by constant arsenite, As(III), excretion back into the solution. Arsenate taken up into the lichens from 0, 0.1, 1, 10 μg mL -1 As(V) solutions was partially transformed into As(III), dimethylarsinic acid (DMA) and (mono)methylarsonic acid (MA). 48 h after exposure, the main arsenic compound in the lichens was DMA in 0.1, As(III) in 1 and As(V) in 10 μg mL -1 treatment. The proportion of methylated arsenic compounds decreased with increasing arsenate concentration in the exposure solution. These results suggest that at least two types of As(V) detoxification exist in lichens; arsenite excretion and methylation. - Lichens are able to metabolize the inorganic arsenic taken up

  20. 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.

  1. Oral Lichen Planus in a Pediatric Patient: A Novel Therapeutic Approach

    Science.gov (United States)

    Sharma, Gaurav; Vohra, Puneeta; Rehani, Shweta; Nagpal, Archna

    2017-01-01

    Lichen planus is a mucocutaneous disease, predominantly affecting the middle-aged individuals and may be associated with a plethora of signs and symptoms related to the skin, scalp, nails and mucous membranes. The definitive etiology of lichen planus is not yet known and no therapeutic modality has yet been universally accepted. Lichen planus in pediatric patients is a rare phenomenon and its presence in the oral mucosa is even rarer. The aim of this article is to present a rare case of a symptomatic oral lichen planus (OLP) occurring in a 12-year old child that was managed successfully with a novel sequential modality of topical retinoids followed by aloe vera gel application. PMID:29104603

  2. Oral Lichen Planus in a Pediatric Patient: A Novel Therapeutic Approach.

    Science.gov (United States)

    Sharma, Gaurav; Sardana, Divesh; Vohra, Puneeta; Rehani, Shweta; Nagpal, Archna

    2017-03-01

    Lichen planus is a mucocutaneous disease, predominantly affecting the middle-aged individuals and may be associated with a plethora of signs and symptoms related to the skin, scalp, nails and mucous membranes. The definitive etiology of lichen planus is not yet known and no therapeutic modality has yet been universally accepted. Lichen planus in pediatric patients is a rare phenomenon and its presence in the oral mucosa is even rarer. The aim of this article is to present a rare case of a symptomatic oral lichen planus (OLP) occurring in a 12-year old child that was managed successfully with a novel sequential modality of topical retinoids followed by aloe vera gel application.

  3. 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.

  4. 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

  5. ASSESSMENT OF ANTIMICROBIAL AND PHYTOCHEMICAL POTENTIALS OF HIGH ALTITUDINAL NEPALESE LICHENS

    Directory of Open Access Journals (Sweden)

    Bijaya Laxmi Maharjan

    2011-10-01

    Full Text Available Lichens and lichen products have been used in traditional medicines for centuries. The lichens of the high altitudinal meadow of MCA (Manaslu Conservation Area have remained unexplored for which this research has been conducted with an aim of unveiling the phytochemical and antimicrobial properties of lichens present there. Four densely populated lichen species namely Usnea longifolia, Setraria spp, Parmotrema reticulatum and Evernastrium nepalense were chosen for the study. The extracts of these species were obtained in 6 different solvents viz. hexane, chloroform, ethyl acetate, acetone, methanol and water by soxhlet extraction method and the antimicrobial assay was carried out by agar well diffusion method. The extract yield varied from 0.07 -29.4%. The extracts obtained showed the presence of volatile oil, saponins, coumarins and quinines, flavonic glycosides and carotenoids. The ethyl acetate fraction of E. nepalense and U. longifolia were found to be most effective against all the 8 clinical bacterial pathogens and 5 phytopathogenic fungi tested. The extracts of Cetraria spp and P. milghenensis were found to be specifically inhibiting the fungal pathogens compared to the bacterial pathogens. Generally the lichen extracts tested demonstrated antimicrobial effect which suggests a possibility of their use in treatment of various diseases caused by these and similar microorganisms.

  6. Oesophageal lichen planus: the efficacy of topical steroid-based therapies.

    Science.gov (United States)

    Podboy, A; Sunjaya, D; Smyrk, T C; Murray, J A; Binder, M; Katzka, D A; Alexander, J A; Halland, M

    2017-01-01

    Oesophageal lichen planus is an idiopathic inflammatory disorder characterized by significant oesophageal stricturing. Oesophageal lichen planus is a rare, difficult to diagnose, and likely an under recognized disease. As a result, there is no standardized approach to therapy and treatment strategies vary. To examine the utility of topical steroid therapy (fluticasone or budesonide) in the management of oesophageal lichen planus. A retrospective chart review was conducted of patients diagnosed with oesophageal lichen planus who underwent baseline and follow up endoscopy pre and post topical steroid therapy between 1995 and 2016 at Mayo Clinic, Rochester MN. Average time between upper GI endoscopy was 3.2 months (0.7-11.7). Swallowed steroid preparations included fluticasone 880 μg twice daily or budesonide 3 mg twice daily. Patients were reviewed for symptomatic response to therapy using the Dakkak-Bennett dysphagia score (0-4, no dysphagia to total aphagia). Pre- and post-endoscopic findings were assessed. Additional baseline demographic, endoscopic, and histologic data were also obtained. We identified 40 patients who met the inclusion criteria. A significant reduction in median dysphagia score from 1 (0-4) to 0 (0-3) after steroid therapy (P lichen planus. © 2016 John Wiley & Sons Ltd.

  7. 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.

  8. Degradation of the disease-associated prion protein by a serine protease from lichens

    Science.gov (United States)

    Johnson, C.J.; Bennett, J.P.; Biro, S.M.; Duque-Velasquez, J.C.; Rodriguez, C.M.; Bessen, R.A.; Rocke, T.E.; Bartz, Jason C.

    2011-01-01

    The disease-associated prion protein (PrP(TSE)), the probable etiological agent of the transmissible spongiform encephalopathies (TSEs), is resistant to degradation and can persist in the environment. Lichens, mutualistic symbioses containing fungi, algae, bacteria and occasionally cyanobacteria, are ubiquitous in the environment and have evolved unique biological activities allowing their survival in challenging ecological niches. We investigated PrP(TSE) inactivation by lichens and found acetone extracts of three lichen species (Parmelia sulcata, Cladonia rangiferina and Lobaria pulmonaria) have the ability to degrade prion protein (PrP) from TSE-infected hamsters, mice and deer. Immunoblots measuring PrP levels and protein misfolding cyclic amplification indicated at least two logs of reductions in PrP(TSE). Degradative activity was not found in closely related lichen species or in algae or a cyanobacterium that inhabit lichens. Degradation was blocked by Pefabloc SC, a serine protease inhibitor, but not inhibitors of other proteases or enzymes. Additionally, we found that PrP levels in PrP(TSE)-enriched preps or infected brain homogenates are also reduced following exposure to freshly-collected P. sulcata or an aqueous extract of the lichen. Our findings indicate that these lichen extracts efficiently degrade PrP(TSE) and suggest that some lichens could have potential to inactivate TSE infectivity on the landscape or be a source for agents to degrade prions. Further work to clone and characterize the protease, assess its effect on TSE infectivity and determine which organism or organisms present in lichens produce or influence the protease activity is warranted.

  9. Lichens as biomonitors of atmospheric ammonium/ammonia deposition in Portugal

    International Nuclear Information System (INIS)

    Capelao, A.L.; Maguas, C.; Branquinho, C.; Cruz, C.; Martins-Loucao, M.A.

    2000-01-01

    The aim of the present work was to evaluate the potentiality of lichens as biomonitors of NH 4 + /NH 3 (ammonium/ammonia) and NO 3 - (nitrate) atmospheric deposition. For that, we used as a field station a rice plantation which is submitted, once a year, to air spraying fertilization with a mixture of nitrogen sources. Samples of an epiphytic lichen, Ramalina fastigiata, were collected from an ash-tree bordering the rice-plantation by the Sorraia River Valley (Central Portugal). The study started one month before fertilization and sampling was carried out for five months. The concentration of ammonium in the lichen was highly and significantly correlated with the number of days without precipitation before sampling, and had an inverse correlation with fluorescence values. Under these conditions, the amount of NH 4 + found in the lichen appears to reflect ammonium/ammonia dry deposition. (author)

  10. A CHARACEAN THALLUS WITH ATTACHED GYROGONITES AND ASSOCIATED FOSSIL CHAROPHYTES FROM THE MAASTRICHTIAN OF THE EASTERN PYRENEES (CATALONIA, SPAIN)(1).

    Science.gov (United States)

    Villalba-Breva, Sheila; Martín-Closas, Carles

    2011-02-01

    The new species Clavatoraxis microcharophorus is described from the Lower Maastrichtian of the Eastern Pyrenees (Catalonia, Spain). Microchara sp. gyrogonites were found in anatomical connection with this thallus, attached to bract-cell rosettes and coated by a structural tunica, formed by an expanded bract cell. This is a feature unknown in extant characeans, which only display lime incrustations similar to tunicae in extremely alkaline and well-illuminated environments. This is the first time that a complete fossil characean is described. The attribution of characean vegetative remains to the genus Clavatoraxis shows that this genus is not exclusive of clavatoraceans as previously thought. The taphonomic study of C. microcharophorus sp. nov. and associated fossil charophytes, along with sedimentological and microfacies analyses, has enabled us to characterize the habitat of this species in the Maastrichtian lake of Vallcebre. They grew forming meadows, and their remains were deposited in the poorly oxygenated lake bottom, where they were well preserved. A number of other characeans and porocharaceans were living in shallower belts. This was the case for Peckichara sp. and Munieria grambasti in the freshwater lacustrine meadows. Another species, Feistiella malladae, was found parautochthonous in brackish lakes. © 2011 Phycological Society of America.

  11. 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

  12. 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...

  13. Lichens biomonitoring as feasible methodology to assess air pollution in natural ecosystems: combined study of quantitative PAHs analyses and lichen biodiversity in the Pyrenees Mountains.

    Science.gov (United States)

    Blasco, María; Domeño, Celia; Nerín, Cristina

    2008-06-01

    The air quality in the Aragón valley, in the central Pyrenees, has been assessed by evaluation of lichen biodiversity and mapped by elaboration of the Index of Air Purity (IAP) based on observations of the presence and abundance of eight kinds of lichen with different sensitivity to air pollution. The IAP values obtained have been compared with quantitative analytical measures of 16 PAHs in the lichen Evernia prunastri, because this species was associated with a wide range of traffic exposure and levels of urbanization. Analyses of PAHs were carried out by the DSASE method followed by an SPE clean-up step and GC-MS analysis. The concentration of total PAHs found in lichen samples from the Aragón valley ranged from 692 to 6420 ng g(-1) and the PAHs profile showed predominance of compounds with three aromatic rings. The influence of the road traffic in the area has been shown because values over the median concentration of PAHs (>1092 ng g(-1)), percentage of combustion PAHs (>50%), and equivalent toxicity (>169) were found in lichens collected at places exposed to the influence of traffic. The combination of both methods suggests IAP as a general method for evaluating the air pollution referenced to PAHs because it can be correlated with the content of combustion PAHs and poor lichen biodiversity can be partly explained by the air pollution caused by specific PAHs.

  14. 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.

  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. Lichens in the Urban Environment within South-East of Western Siberia, Russia

    Directory of Open Access Journals (Sweden)

    Ekaterina V. Romanova

    2013-12-01

    Full Text Available Lichen species diversity and trend of their distribution were studied in two big cities and fi ve towns in south-east of Western Siberia. In total of 348 species from 46 families and 98 genera were found in all studied urban and suburban areas. All local checklists are characterized by high degree of the lichen species similarity between each other and smaller lists are included in bigger ones on to 64-100%. Epiphytic lichens were the largest group in all studied areas and almost half of them were occupied two and more substrates. Crustose life-form and mesophytes prevailed everywhere. Share of sensitive lichens exceeded percent of tolerant ones in big cities and was lower than tolerant ones in smaller towns. The sixteen species were the most tolerant, commonly present everywhere and have been recognized as the key species for urban lichen synusiae within south-east of Western Siberia. Five zones have been determined with IP-mapping (mapping on the base of index of air pollution tolerance in studied areas: IP=3-5 is a “normal zone”, IP=5-7 is a “moderate exposure zone”, IP=7-9 is a “mixed zone”, IP=9-10 is a “struggle zone”, and fi nally – lichen-free zone. The most studied urban areas had got quite extensive lichen-free zone (up to 35% of their areas.

  17. 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).

  18. Dead trees and living lichens - a phenomenon of the novel decline of forests

    Energy Technology Data Exchange (ETDEWEB)

    John, V

    1986-01-11

    In several hundred publications the effect of sulfur dioxide on lichens has been very well documented. Now a somewhat one-sided analysis of the relation between the absence of lichens and high sulfur dioxide immission has caused considerable confusion in connection with that specific damage now noted in forests, all the more as lichens are often spoken of without taking into account the sensitivity of different species or the multitude of species. A further handicap to the use of lichens as biological indicators is also that the statistical methods adopted for the verification of immissions in towns cannot simply be taken over. There is need to take more into consideration the different ecophysiological conditions. Furthermore increased attention must be paid to pollutants whose effects on lichens are little known so far. Thus this concise overview on the effect of ozone, nitrogen dioxide and peroxyacetyl nitrate may contribute to better understanding of the phenomenon of the presence and absence of lichens in declining forest areas.

  19. Canopy, snow, and lichens on woodland caribou range in southeastern Manitoba

    Directory of Open Access Journals (Sweden)

    James A. Schaefer

    1996-01-01

    Full Text Available I examined the relationships among snow cover (api, lichen abundance, and canopy composition on the range of the Aikens Lake population of woodland caribou (Rangifer tarandus caribou in southeastern Manitoba. Percent cover of forage lichens (Cladina spp. was positively correlated with maximum total thickness and with maximum vertical hardness of api. Mixed communities of trembling aspen (Populus tremuloides, spruce (Picea spp., and balsam fir (Abies balsamea showed the most favourable nival conditions for caribou but had low lichen abundance; those dominated by jack pine (Pinus banksiana were the converse. The results suggest an energetic compromise for woodland caribou when foraging for terrestrial lichens. During winter, caribou exhibited significant selection for jack pine communities whereas mixed communities were avoided.

  20. Relationships between lichen community composition and concentrations of NO{sub 2} and NH{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Gadsdon, Sally R., E-mail: sally.gadsdon@cityoflondon.gov.u [Division of Biology, Imperial College London, Silwood Park Campus, Ascot, Berkshire SL5 7PY (United Kingdom); Dagley, Jeremy R., E-mail: jeremy.dagley@cityoflondon.gov.u [City of London Corporation, Epping Forest, The Warren, Loughton, Essex IG10 4RW (United Kingdom); Wolseley, Patricia A., E-mail: patw@nhm.ac.u [Department of Botany, Natural History Museum, Exhibition Road, South Kensington, London SW7 5BD (United Kingdom); Power, Sally A., E-mail: s.power@imperial.ac.u [Division of Biology, Imperial College London, Silwood Park Campus, Ascot, Berkshire SL5 7PY (United Kingdom)

    2010-08-15

    The relationship between different features of lichen communities in Quercus robur canopies and environmental variables, including concentrations of NO{sub 2} and NH{sub 3} was investigated. NO{sub 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{sub 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.

  1. 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.

  2. 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.

  3. Introduce lichen Lepraria incana as biomonitor of Cesium-137 from Ramsar, northern Iran.

    Science.gov (United States)

    Dalvand, Amin; Jahangiri, Ahmad; Iranmanesh, Jalil

    2016-08-01

    Lichens have been used as biomonitors of airborne radionuclides released in conjunction with nuclear bomb testing as well as nuclear power plant accidents. The potential of lichens for monitoringof radionuclides has been well documented. However, there are no studies that determine natural and artificial radionuclide monitoring by lichens, in Iran. Thus, as a first step, we have conducted a comparison of (137)Csactivity concentration capacity of three epiphytic lichen species including Lepraria incana, Xanthoria parietina and Ramalina farinacea from Ramsar Northern Iran. In this work, accumulation capacity of (137)Cs was determined in 36 lichen samples using a gamma spectrometer equipped with a high purity germanium (HPGe) detector. The results showed that highest accumulation capacity of (137)Cs in the lichen species was found in Lepraria incana and Xanthoria parietina, 30.2, 9.8 Bq/kg respectively, and lowest average accumulation capacity were found in Ramalina farinacea 2.7 Bq/kg (dry weight). This study showed that activity concentration (137)Cs is in crustose > foliose > fruticose lichens in the same biotope. Thus, crustose lichens are capable to accumulate higher (137)Cs than foliose and fruticose species because of different factors such as special morphological characteristics in these species and large surface/volume ratio or longer biological half-life of (137)Cs in lichen Lepraria incana. Therefore, Lepraria incana due to high concentration capability of (137)Cs (approximately 3 and 11 time higher than Xanthoria parietina and Ramalina farinacea, respectively), is introduced as biomonitor of Cesium-137 from Ramsar, North of Iran. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. 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)

  5. Diagnostic profiling of salivary exosomal microRNAs in oral lichen planus patients.

    Science.gov (United States)

    Byun, J-S; Hong, S-H; Choi, J-K; Jung, J-K; Lee, H-J

    2015-11-01

    Oral lichen planus is a chronic inflammatory oral mucosal disease whose exact cause is unclear and which requires efficient diagnostic and therapeutic strategies. Identification of disease-specific biomarkers in saliva is an easy, quick, and non-invasive approach for molecular diagnosis. This study was designed to examine salivary exosomal microRNAs (miRNAs) that could be candidates for diagnosing and elucidating the pathogenesis of oral lichen planus. We compared miRNA profiles of salivary exosomes of patients with oral lichen planus with those of healthy controls. Saliva samples from 16 patients with oral lichen planus and eight healthy controls were divided into two sets and examined using miRNA microarray analysis and TaqMan quantitative PCR. The three miRNAs identified (miR-4484, miR-1246, and miR-1290) were further validated. Of these, miR-4484 was significantly upregulated in the salivary exosomes of patients with oral lichen planus. This study thus identifies a potential miRNA biomarker for oral lichen planus and provides insight into the functions of miRNAs in the pathogenesis of oral inflammatory diseases. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  6. Prevalence of oral lichen planus in Iranian children and adolescents: a 12-year retrospective study.

    Science.gov (United States)

    Bakhtiari, S; Taheri, J B; Toossi, P; Azimi, S; Kawosi Nezhad, Sh

    2017-12-01

    To investigate the prevalence of oral lichen planus in patients younger than 18 years, referred to a dermatology centre in Iran during 2002-2014. Lichen planus is a chronic inflammatory, immune-mediated disease that could affect the oral mucosa and is a pre-cancerous condition. The disease usually develops in middle age with female predominance and is rare in children. In this retrospective study, cases with definitive histopathologic diagnosis of lichen planus, over a 12-year period from 2002 to 2014 from a dermatologic hospital archive were evaluated. The prevalence of both cutaneous and oral lichen planus, the male:female ratio and site of involvement were calculated using SPSS version 21. Thirty-six of 564 patients younger than 18 years old diagnosed with lichen planus. Two females (0.4%) had oral lichen planus. One patient had erosive, and one had bullous, oral lichen planus. Oral lichen planus had a very low frequency in Iranian population younger than 18 years old, identifying these patients is recommended for long-term follow-up.

  7. Mean annual response of lichen Parmelia sulcata 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

    Lichens collected in an area previously identified as unpolluted, were transplanted to six different places located in polluted areas near Power Plants (both fuel and coal powered). A total of 26 lichen transplants were made for each place, each transplant weighing about 2g. Two were analysed as zero or reference and the remain 24 were hanged in nylon net bags in order to be able to collect two transplants each month, out of every station during a one year period. Besides the 24 lichen samples, each station was provided with two total deposition collection 10 litter buckets (with 25 cm diameter funnels) and an aerosol sampler. Concentration in both lichens and aerosols were measured by PIXE and INAA at ITN. Total deposition residues were analysed by ICP-MS at the The Netherlands Geological Survey. On this work we present the results obtained by looking for correlation between lichens elemental concentrations and annual averages of elemental availability variables such as concentration in suspension in the atmosphere and concentration in total deposition samples, for a total of 40 elements. In order to access both the limitations and the reliability of the results a discussion on the details of handling this data set is presented. A mathematical function which tentatively represents the lichen up-take response to water availability is also proposed. (author)

  8. 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)....

  9. 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.

  10. 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)

  11. 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...

  12. Frequency of Genital Involvement in Women with Oral Lichen Planus in Southern Iran

    Directory of Open Access Journals (Sweden)

    M. Davarmanesh

    2012-01-01

    Full Text Available Background. Lichen Planus is a chronic mucocutaneous disease of immunological basis and unknown etiology. women with oral lichen planus may have concomitant manifestations in vulvovaginal areas. Objective. To determine the frequency and risk factors of genital involvement in a group of Iranian women affected by oral lichen planus. Methods. Thirty-six women with clinical and histopathological diagnosis of oral lichen planus were evaluated for demographic, historical, and clinical parameters of the oral disease. All the patients were referred for careful vulvovaginal examination, as well as histopathological assessment upon clinical indication. Results. Nineteen patients complained from genital symptoms but the number of women with the final diagnosis of genital lichen planus (=2 was too small to show any correlation with the parameters evaluated. Conclusion. In spite of low genital involvement possibly due to inadequate patient population, lack of follow-up visits, and contribution of genetic or ethnic factors, for conservative patient care, women with the oral lichen planus in particular those having some relevant genital symptoms, should preferably be referred for careful vulvovaginal examination. Multicenter cohort studies on women of different geographical regions or ethnicities who have genital lichen planus alone or in combination with other common sites are encouraged.

  13. Influence of industrial smoke on the germination spores of certain lichens

    Energy Technology Data Exchange (ETDEWEB)

    Kofler, L; Jacquard, F; Martin, J F

    1968-01-01

    Dust particles produced by calcium carbide and iron-alloy factories strongly inhibit the germination of the spores of Physcia pulverulenia. The spores of Xanthoria parietina and above ali of Lecanora hageni are much more resistant. This agrees with the distribution of these Lichens around the factories. The three species show the same scale of resistance with respect to town dust. The basicity of the particles plays certainly a part in the inhibition of spores, but this can not be the only active factor. Up to now attention has been drawn upon the damages caused by gaseous pollutants to Lichen gonidia. The present work shows that solid particles can sometimes be responsible for Lichen scarcity and that the Lichen fungus is also sensitive to certain pollutants. 9 references, 1 figure, 5 tables.

  14. 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

  15. Observations made in Belfast City, Northern Ireland, on lichens as indicators of atmospheric pollution

    Energy Technology Data Exchange (ETDEWEB)

    Fenton, A F.G.

    1972-01-01

    Smoke, solids fall-out and SO/sub 2/ concentrations were measured at a number of stations in the Belfast area. Using the data available from these stations an investigation of the lichen flora was undertaken during May 1962. No lichens of any sort exist within half a mile to the south of the center of pollution. This lichen desert zone extends from one and a half to two miles on the northern, eastern, and western sides. From the known levels at these distances it is established that no lichen species will tolerate smoke and SO/sub 2/ concentrations in excess of 25-30 mg per 100 cubic meters, and 3.5 parts per 100 million respectively. Outside this lichen desert zone crustaceous lichens are the first to appear and in the Belfast area are represented by a single species, Leconora pityrea. This lichen remains the only one present for a distance of one and a half to two miles on the southern side and for up to four miles distant in the other directions. Foliaceous lichens only enter at distances greater than this from the main concentration. The smoke pollution level at which foleaceous species enter does not exceed 10 mg pr 100 cubic meters, and the SO/sub 2/ concentration is probably not in excess of 0.5 parts per 100 million. The use of lichens as indicators of pollution could be considerably extended as a cheap and positive method for preliminary investigations of areas of suspected pollution. 8 references.

  16. Biogeography and ecology of Cetraria aculeata, a widely distributed lichen with a bipolar distribution

    Directory of Open Access Journals (Sweden)

    Christian Printzen

    2013-04-01

    Full Text Available Ecological and historical biogeography of lichens have rarely been studied in a concerted effort, but both aspects have to be taken into consideration when explaining the distributional patterns of species. This review summarizes, partly preliminary, results from a series of studies on phylogeography, ecophysiology and symbiotic interactions of the lichen Cetraria aculeata. This species is not only widespread but also occupies a very wide ecological niche. Evidence suggests that Cetraria aculeata has evolved and diversified in the Northern Hemisphere and colonised the Southern Hemisphere from there. Genetic isolation of populations indicates the absence of ongoing long range dispersal and genetic exchange between geographically isolated populations. We observe a hitherto unrecognized genetic diversity that may indicate ecotypic differentiation and speciation processes. Mediterranean and Polar populations differ not only genetically, but also in ecophysiological properties. Ongoing common garden experiments will have to show whether genetically fixed adaptation or acclimation is responsible for these differences. The genetic structure of the photobiont is best explained by climatic differences between localities, but co-dispersal with the mycobiont plays an important role as well. Taken together, these results indicate that a photobiont switch in the past enabled C. aculeata to widen its ecological niche, with subsequent genetic isolation of populations. Photobiont switches may play a crucial role in speciation processes of lichens. A combination of ecophysiological and phylogeographic studies with experimental approaches is necessary to better understand the reaction of lichens to changing environmental conditions.

  17. A retrospective clinico-pathological study comparing lichen planus pigmentosus with ashy dermatosis.

    Science.gov (United States)

    Cheng, Hui Mei; Chuah, Sai Yee; Gan, Emily Yiping; Jhingan, Anjali; Thng, Steven Tien Guan

    2018-04-10

    Controversy persists as to whether lichen planus pigmentosus and ashy dermatosis are separate clinical entities. This study was conducted to examine the clinicopathological features and treatment outcome of the two conditions. A retrospective medical chart review of all patients who were diagnosed with lichen planus pigmentosus or ashy dermatosis was conducted. The information collected included the participants' age at onset, site of onset, duration of disease, presence of precipitating factors, distribution of disease, pigmentation and presence of symptoms. In patients from whom a biopsy was taken the histopathological reports were included. Altogether 26 patients with ashy dermatosis and 29 with lichen planus pigmentosus were included in the study. Compared with ashy dermatosis, lichen planus pigmentosus had a more localised distribution with a preponderance for facial involvement, compared with the truncal preponderance in ashy dermatosis. Ashy dermatosis tended to have a more stable clinical course than lichen planus pigmentosus, which was more likely to wax and wane. The utility of histopathology in differentiating between the two conditions is low. Ashy dermatosis and lichen planus pigmentosus, as defined in this study, appear to be two separate clinical entities with distinguishable clinical features and natural histories. © 2018 The Australasian College of Dermatologists.

  18. 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...

  19. Dysbiosis of oral buccal mucosa microbiota in patients with oral lichen planus.

    Science.gov (United States)

    He, Y; Gong, D; Shi, C; Shao, F; Shi, J; Fei, J

    2017-07-01

    The bacterial community structure of buccal mucosa in patients with oral lichen planus was evaluated and compared with healthy control. Buccal scraping samples have been taken on 43 oral lichen planus patients (21 erosive and 22 non-erosive) and 21 mucosal healthy volunteers. The V3 hypervariable 16S rDNA region was amplified and sequenced by high-throughput 454 pyrosequencing. 94.26% of the total buccal bacteria were classified into 15 abundant genera. Eight of these abundant genera could be detected in all cases, namely Streptococcus, Prevotella, Haemophilu, Neisseria, Fusobacterium, Leptotrichia, Veillonella and Actinomyces. Four abundant bacteria showed significantly different prevalence at the genus level: Streptococcus was more abundant (P oral microbiome. Further studies should be taken to elucidate the inner relationship between these observed changes and OLP development. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  20. Lichen planus following tetanus-diphtheria-acellular pertussis vaccination: A case report and review of the literature.

    Science.gov (United States)

    Rosengard, Heather C; Wheat, Chikoti M; Tilson, Matthew P; Cuda, Jonathan D

    2018-01-01

    Lichen planus is an inflammatory dermatosis with a prevalence of approximately 1%. Recent meta-analyses show that patients with hepatitis C virus have a 2.5- to 4.5-fold increased risk of developing lichen planus. Lichen planus has also followed vaccinations and has specifically been attributed to the hepatitis B vaccine, the influenza vaccine, and the tetanus-diphtheria-acellular pertussis vaccine. We describe a case of lichen planus in a hepatitis C virus-infected African American male occurring in temporal association with the administration of the tetanus-diphtheria-acellular pertussis vaccine. The patient's presentation was clinically consistent with lichen planus and confirmed by biopsy. It is likely that many cases of vaccine-induced lichen planus have gone unpublished or unrecognized. In areas with high prevalence of hepatitis C virus infection, we may expect to see more cases of vaccine-induced lichen planus especially in light of the updated Centers for Disease Control and Prevention tetanus-diphtheria-acellular pertussis vaccination recommendations. This case serves to educate healthcare providers about vaccine-induced lichen planus and, in particular, the need to counsel hepatitis C virus-infected patients about a potential risk of developing lichen planus following vaccination. We also reflect on current theories suggesting the T-cell-mediated pathogenesis of lichen planus and the role that hepatitis C virus and toxoid or protein vaccines may play in initiating the disease.

  1. Lichens as indicators of the atmosphere state in the oil exploration district of Tomsk Region

    Science.gov (United States)

    Bolshunova, Tatiana; Ivan, Podkozlin

    2013-04-01

    Lichens are widespread in the vegetative cover of West Siberia, particularly in the north. They play an important role in the migration and transformation of chemical pollutants. Lichens lack waxy cuticles and are largely dependent on the atmosphere for their water and nutrient uptake. Lichens are not only studied and used as indicators, but also as accumulators, e.g. for trace and heavy metals. In fact, lichens are known for their ability to accumulate airborne substances to concentrations far greater those in the atmosphere, and the element contents of lichen thalli proved to be directly correlated with environmental levels. Monitoring of the atmosphere pollution using lichens is more efficient than that using snow cover. Because of the long lichen life it is possible to obtain persistent mean characteristics of the ecosystems state. Epiphytic lichens, growing on tree stems are more appropriate to use than that which grow on soil. Epiphytic lichens are more sensitive to changes of the chemical composition of the atmosphere. Pollutants penetrate in the lichen thalli from the atmosphere together with precipitations and dust. Moreover the precipitations are saturated with pollutants when going through crowns of trees and trickling down the steams and branches. Lichen studies are especially important in territories subjected to excessive human activity. Because a great part of Tomsk region (West Siberia, Russia) is the territory of the oil-field exploration, there the atmosphere monitoring is a necessary part of the whole environmental monitoring. The aim of this investigation is the estimation of the influence of oil exploration industry in Tomsk region on the atmosphere by means of the study of epiphytic lichens. Lichen samples were collected in August and September 2010-2011. Sampling net included seven areas distributed inside the oil-exploration districts of Tomsk region. In total 27 samples were collected. In these samples 53 chemical elements were detected by

  2. 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...

  3. 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 ...

  4. Nature reserve Pfaueninsel in Berlin-Wannsee. V. The Lichen Flora

    Energy Technology Data Exchange (ETDEWEB)

    Grummann, V J; Poelt, J

    1972-01-01

    During the years 1965-1971 about 95 species of lichens were identified within the district of West Berlin. A few of them were growing on trees; corticolous foliaceous species are present in very reduced numbers, and the surviving individuals do not appear healthy. The majority of the species are found on walls and large rocks or on the ground in pine woods. Even these species are showing signs of diminution. Several species seem to have disappeared since the beginning of the observations. Air pollution is singled out as the cause of the decline of the lichens. Berlin today must be considered a lichen desert. 29 references, 2 figures.

  5. 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.

  6. 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.

  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. 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 ...

  9. 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.)

  10. 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.

  11. 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.

  12. Citizen science identifies the effects of nitrogen deposition, climate and tree species on epiphytic lichens across the UK.

    Science.gov (United States)

    Welden, N A; Wolseley, P A; Ashmore, M R

    2018-01-01

    A national citizen survey quantified the abundance of epiphytic lichens that are known to be either sensitive or tolerant to nitrogen (N) deposition. Records were collected across the UK from over 10,000 individual trees of 22 deciduous species. Mean abundance of tolerant and sensitive lichens was related to mean N deposition rates and climatic variables at a 5 km scale, and the response of lichens was compared on the three most common trees (Quercus, Fraxinus and Acer) and by assigning all 22 tree species to three bark pH groups. The abundance of N-sensitive lichens on trunks decreased with increasing total N deposition, while that of N-tolerant lichens increased. The abundance of N-sensitive lichens on trunks was reduced close to a busy road, while the abundance of N-tolerant lichens increased. The abundance of N-tolerant lichen species on trunks was lower on Quercus and other low bark pH species, but the abundance of N-sensitive lichens was similar on different tree species. Lichen abundance relationships with total N deposition did not differ between tree species or bark pH groups. The response of N-sensitive lichens to reduced nitrogen was greater than to oxidised N, and the response of N-tolerant lichens was greater to oxidised N than to reduced N. There were differences in the response of N-sensitive and N-tolerant lichens to rainfall, humidity and temperature. Relationships with N deposition and climatic variables were similar for lichen presence on twigs as for lichen abundance on trunks, but N-sensitive lichens increased, rather than decreased, on twigs of Quercus/low bark pH species. The results demonstrate the unique power of citizen science to detect and quantify the air pollution impacts over a wide geographical range, and specifically to contribute to understanding of lichen responses to different chemical forms of N deposition, local pollution sources and bark chemistry. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. 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.

  14. 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.

  15. 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.

  16. Genotype variation in bark texture drives lichen community assembly across multiple environments.

    Science.gov (United States)

    Lamit, L J; Lau, M K; Naesborg, R Reese; Wojtowicz, T; Whitham, T G; Gehring, C A

    2015-04-01

    A major goal of community genetics is to understand the influence of genetic variation within a species on ecological communities. Although well-documented for some organisms, additional research is necessary to understand the relative and interactive effects of genotype and environment on biodiversity, identify mechanisms through which tree genotype influences communities, and connect this emerging field with existing themes in ecology. We employ an underutilized but ecologically significant group of organisms, epiphytic bark lichens, to understand the relative importance of Populus angustifolia (narrowleaf cottonwood) genotype and environment on associated organisms within the context of community assembly and host ontogeny. Several key findings emerged. (1) In a single common garden, tree genotype explained 18-33% and 51% of the variation in lichen community variables and rough bark cover, respectively. (2) Across replicated common gardens, tree genotype affected lichen species richness, total lichen cover, lichen species composition, and rough bark cover, whereas environment only influenced composition and there were no genotype by environment interactions. (3) Rough bark cover was positively correlated with total lichen cover and richness, and was associated with a shift in species composition; these patterns occurred with variation in rough bark cover among tree genotypes of the same age in common gardens and with increasing rough bark cover along a -40 year tree age gradient in a natural riparian stand. (4) In a common garden, 20-year-old parent trees with smooth bark had poorly developed lichen communities, similar to their 10-year-old ramets (root suckers) growing in close proximity, while parent trees with high rough bark cover had more developed communities than their ramets. These findings indicate that epiphytic lichens are influenced by host genotype, an effect that is robust across divergent environments. Furthermore, the response to tree genotype is

  17. Lichen planus and Hepatitis C: A case-control study | Elagraa ...

    African Journals Online (AJOL)

    Background The exact cause of LP is not known. However, the association of lichen planus with hepatitis C virus (HCV) infection has been reported in literature. A wide variation in the reported prevalence of HCV infection in patients with lichen planus in different geographical areas was observed. This case – control study ...

  18. 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.

  19. 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.

  20. Comparative study of the suitability of two lichen species for trace element atmospheric monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Saiki, Mitiko; Alves, Edson R.; Genezini, Frederico A., E-mail: mitiko@ipen.br, E-mail: eralves@ipen.br, E-mail: fredzini@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN-CNEN-SP), Sao Paulo, SP (Brazil); Saldiva, Paulo H.N., E-mail: pepino@usp.br [Universidade de Sao Paulo (USP), Sao Paulo, SP (Brazil). Faculdade de Medicina

    2013-07-01

    Lichens have been widely used in monitoring studies. Consequently, it is very useful to study the suitability of lichen species to monitor pollutants allowing in this way the best choice. The aim of this study was to compare the accumulation of trace elements by two epiphytic lichen species Canoparmelia texana (Tuck) Elix and Hale and Usnea amblyoclada (Mull. Arg.) Zahlbr. Five samples of each species were collected during the period from November 2010 in a same site far from downtown Sao Paulo city. Lichens collected from tree barks were cleaned, freeze-dried, ground and analyzed by neutron activation analysis. Aliquots of lichen samples and synthetic elemental standards were irradiated at the IEA-R1 nuclear research reactor. The induced gamma activities were measured using a hyperpure Ge detector coupled to a digital spectrum analyzer. Concentrations of As, Ba, Cd, Cr, Cs, Fe, Mg, Mn, Na, Rb, V and Zn were determined in both lichen species. The results demonstrated that both species can be used for evaluating air quality. The element concentrations showed difference between lichen species and also among their sampling periods. These differences may be attributed to the distinct mechanisms of element absorption by lichens as well as various other factors that affect their element accumulation. The comparative evaluation made calculating the ratios between C. texana species sample and that in Usnea amblyoclada for elemental concentrations indicated that, in general, foliose C. texana present similar or higher concentrations than those presented by fruticose Usnea. (author)

  1. 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...

  2. 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.

  3. 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.

  4. [Oral squamous cell carcinoma and lichen planus vs. lichenoid lesions. Case report].

    Science.gov (United States)

    Esquivel-Pedraza, Lilly; Fernández-Cuevas, Laura; Ruelas-Villavicencio, Ana Lilia; Guerrero-Ramos, Brenda; Hernández-Salazar, Amparo; Milke-García, María Pilar; Méndez-Flores, Silvia

    2016-01-01

    The development of squamous cell carcinoma from oral lichen planus is controversial. We report a case of intraoral squamous cell carcinoma, which presents together with lesions of oral lichen planus. The aim of this report was to analyze the problem to distinguish between the incipient changes of squamous cell carcinoma from the features described in oral lichen planus, in order to establish an accurate diagnosis of both entities. A 57-year old man with a history of smoking and chronic alcohol intake, who had an ulcerated tumor mass located in the tongue, and bilateral white reticular patches on buccal mucosa and borders of the tongue. The histopathological report was moderately differentiated invasive squamous cell carcinoma and lichen planus respectively. The premalignant nature of OLP is still indeterminate and controversial, this is primarily due to inconsistency in the clinical and histological diagnostic criteria used to differentiate cases of oral lichen planus from lichenoid reactions or other lesions causing intraepithelial dysplasia with high potentially malignant transformation. Oral lichenoid reactions are possibly most likely to develop malignant transformation as compared to the classic OLP lesions.

  5. Oxidation of atmospheric molecular tritium in plant leaves, lichens and mosses

    Energy Technology Data Exchange (ETDEWEB)

    Ichimasa, Michiko; Ichimasa, Yusuke; Yagi, Yoshimi; Ko, Rinkei [Ibaraki Univ., Mito (Japan). Faculty of Science; Suzuki, Masatomo; Akita, Yasukazu

    1989-12-01

    The oxidation of atmospheric molecular tritium (HT) in vegetation was determined by in vitro experiments for pine needles, pine bark, lichens attached to pine trees, taken from a coastal pine forest in Ibaraki prefecture and comparison of such measurements was made with those in soil. The oxidation of HT in pine needles was extremely low, being only about 1/40000 that in the surface soil of a pine forest, whereas its oxidation in pine bark with a lichen was almost 1000-7000 times higher than that in pine needles. HT oxidation in pine bark, a lichen and a moss was determined in each case under light and dark conditions and was found to be essentially the same. All mosses and lichens examined in the present study were found to have unusually high levels of HT oxidation whether their habitat was tree or ground surface. (author).

  6. Oxidation of atmospheric molecular tritium in plant leaves, lichens and mosses

    International Nuclear Information System (INIS)

    Ichimasa, Michiko; Ichimasa, Yusuke; Yagi, Yoshimi; Ko, Rinkei; Suzuki, Masatomo; Akita, Yasukazu.

    1989-01-01

    The oxidation of atmospheric molecular tritium (HT) in vegetation was determined by in vitro experiments for pine needles, pine bark, lichens attached to pine trees, taken from a coastal pine forest in Ibaraki prefecture and comparison of such measurements was made with those in soil. The oxidation of HT in pine needles was extremely low, being only about 1/40000 that in the surface soil of a pine forest, whereas its oxidation in pine bark with a lichen was almost 1000-7000 times higher than that in pine needles. HT oxidation in pine bark, a lichen and a moss was determined in each case under light and dark conditions and was found to be essentially the same. All mosses and lichens examined in the present study were found to have unusually high levels of HT oxidation whether their habitat was tree or ground surface. (author)

  7. 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

  8. 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...

  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. 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

  11. Physiological responses of lichens to factorial fumigations with nitric acid and ozone

    International Nuclear Information System (INIS)

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

    2012-01-01

    This paper addresses the effects of gaseous nitric acid (HNO 3 ) and ozone (O 3 ), two important air pollutants, on six lichen species with different morphological, ecological, and biological characteristics. The treatment chambers were set up in a factorial design consisting of control chambers, chambers fumigated with HNO 3 , with O 3 , and with HNO 3 and O 3 , together. Each species showed a different sensitivity to the fumigations, reflecting the physiological variation among species. Our results clearly indicate that HNO 3 is a strong phytotoxin to many lichens, and that O 3 alone has little effect on the measured parameters. The combined fumigation effects of HNO 3 and O 3 were not significantly different from HNO 3 alone. - Highlights: ► We fumigated 6 lichen species with factorial combinations of nitric acid (HNO 3 ) and ozone (O 3 ). ► Some species were highly sensitive to HNO 3 while others were tolerant. ► No species responded significantly to O 3 . ► The combined fumigation effects of HNO 3 and O 3 were not significantly different from HNO 3 alone. ► HNO 3 may play an important role in lichen community composition in areas with high HNO 3 pollution. - Nitric acid can be highly toxic to lichens through several physiological mechanisms. Ozone is relatively non-toxic to fumigated lichens.

  12. Experimental reproduction of tumbleweed shield lichen (Xanthoparmelia chlorochroa) poisoning in a domestic sheep model.

    Science.gov (United States)

    Dailey, Rebecca N; Montgomery, Donald L; Ingram, James T; Siemion, Roger; Raisbeck, Merl F

    2008-11-01

    Xanthoparmelia chlorochroa, commonly called tumbleweed lichen, is found throughout the Rocky Mountain region. This particular species of lichen was incriminated in the poisoning of cattle and sheep in Wyoming during the 1930s. More than 70 years elapsed before another case was reported. There is virtually no information in the veterinary literature regarding toxicity of this lichen. This report describes X. chlorochroa poisoning in domestic sheep fed lichen collected from different locales and at different times of the year. Affected animals voided red urine and displayed incoordination. A transient spike in serum creatine kinase activity occurred in all ewes during the course of the feeding trial. Histologically, necrosis of a few individual appendicular skeletal myocytes was observed in 1 ewe, but grossly discernible myonecrosis was absent. The severity of clinical signs varied depending on the location and/or time of year the lichen was collected, indicating that toxicity of the lichen may be influenced by environmental conditions. Results demonstrate that domestic sheep are a useful model for further investigation of X. chlorochroa intoxication. The current study should act as a starting point for elucidating the pathogenesis of X. chlorochroa poisoning and aid in the development of a diagnostic assay to confirm lichen poisoning.

  13. 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...

  14. 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.

  15. A retrospective study of 370 patients with oral lichen planus in Turkey

    Science.gov (United States)

    2013-01-01

    Objectives: Although several detailed studies concerning the patient profile and clinical features of oral lichen planus have been undertaken all over the world in different populations, a similar study has not yet been conducted in a Turkish population. The purpose of this retrospective study was to describe the demographic and clinical characteristics of a group of patients with oral lichen planus in Turkey. Study Design: Charts of 370 patients, from the archive of Oral Diagnosis and Radiology Department of Marmara University Faculty of Dentistry (Istanbul, Turkey), with histologically confirmed clinical diagnosis of oral lichen planus in the period 1990-2010 were retrospectively reviewed. Results: Of the 370 patients, 260 (70.3%) were women and 110 (29.7%) were men. The mean age was 49.84±13.41 years (range of 16-83). The lesions were asymptomatic in 63 patients (17%). Nearly half of the patients (47.6%) had multiple sites of involvement. Predominantly red forms were the most frequent, affecting 60.5% of patients. Approximately 17% of the patients had symptoms of possible extraoral involvement. No evidence suggesting a connection between oral lichen planus and tobacco or alcohol use was found. Only one out of the 370 cases had histologically proven malignant transformation. Conclusions: The patient profile and clinical features of oral lichen planus in Turkey were generally similar to those described in other populations. The preponderance of the red forms and also the fact that majority of patients referred themselves to our clinic highlighted the lack of awareness among Turkish health care providers about lichen planus. Key words:Oral lichen planus, clinical features, patient profile. PMID:23524413

  16. In Vitro Antimicrobial Potential of the Lichen Parmotrema sp. Extracts against Various Pathogens.

    Science.gov (United States)

    Chauhan, Ritika; Abraham, Jayanthi

    2013-07-01

    The ongoing increasing antibiotic resistance is one of the biggest challenges faced by global public health. The perennial need for new antimicrobials against a background of increasing antibiotic resistance in pathogenic and opportunistic microorganisms obliges the scientific community to constantly develop new drugs and antimicrobial agents. Lichens are known prolific sources of natural antimicrobial drugs and biologically active natural products. This study was aimed to explore in vitro antimicrobial activity of lichen Parmotrema sp. The methanol and aqueous extracts of lichen Parmotrema sp. was extracted using Soxhlet extractor. Antibiotic assessment of methanol and aqueous extracts was done against eight bacterial (Escherichia coli, Staphylococcus aureus, Proteus mirabilis, Salmonella sp., Shigella sp., Enterococci faecalis, Pseudomonas aeruginosa, Klebsiella pneumoniae,) clinical pathogens and five plant pathogenic fungal strains (Aspergillus terreus strain JAS1, Scedosporium sp. JAS1, Ganoderma sp. JAS4, Candida tropicalis and Fusarium sp.) by Kirby-Bauer method. The methanol lichen Parmotrema sp. extract inhibited all the test organisms. The highest antibacterial activity was found against Pseudomonas aeruginosa and Staphylococcus aureus. The weakest activity was manifested in Salmonella sp. and Scedosporium sp. JAS1. Strong antifungal effect was found against Ganoderma sp. JAS4 and Fusarium sp. The aqueous lichen Parmotrema sp. extract revealed neither antibacterial nor antifungal activity. The present study shows that tested lichen Parmotrema sp. extracts demonstrated a strong antimicrobial effect. That suggests the active components from methanol extracts of the investigated lichen Parmotrema sp. can be used as natural antimicrobial agent against pathogens.

  17. Lichens of fruit trees in the selected locations in Podlaskie Voivodeship [North-Eastern Poland

    Directory of Open Access Journals (Sweden)

    Matwiejuk Anna

    2017-12-01

    Full Text Available The aim of this paper is to present the diversity of the lichen species on fruit trees (Malus sp., Pyrus sp., Prunus sp. and Cerasus sp. growing in orchards in selected villages and towns in the Podlaskie Voivodeship. Fifty-six species of lichens were found. These were dominated by common lichens found on the bark of trees growing in built-up areas with prevailing heliophilous and nitrophilous species of the genera Physcia and Phaeophyscia. A richer lichen biota is characteristic of apple trees (52 species and pear trees (36. Lichens of the apple trees constitute 78% of the biota of this phorophyte growing in the fruit orchards in Poland. Of the recorded species, only two (Ramalina farinacea, Usnea hirta are covered by partial protection in Poland.

  18. Evaluation of mast cells, eosinophils, blood capillaries in oral lichen planus and oral lichenoid mucositis.

    Science.gov (United States)

    Reddy, D Santhosh; Sivapathasundharam, B; Saraswathi, T R; SriRam, G

    2012-01-01

    Mast cells are granule containing secretory cells present in oral mucosal and connective tissue environment. Oral lichen planus and oral lichenoid lesions are commonly occurring oral diseases and have some similarity clinically and histologically. Both are characterized by an extensive sub epithelial infiltrate of T cells, together with mast cells, eosinophils and blood capillaries. In this study mast cell and eosinophil densities along with number of blood capillaries were studied to find out if they could aid in histopathological distinction between oral lichen planus and lichenoid mucositis. To enumerate mast cells and compare the status of Mast Cells (Intact or Degranulated) in Lichen planus, Lichenoid mucositis and normal buccal mucosa in tissue sections stained with Toluidine Blue, and also to enumerate Eosinophils and blood capillaries in tissue sections stained with H and E. The study group included 30 cases each of oral lichen planus and oral lichenoid mucositis. 10 cases of clinically normal oral buccal mucosa formed the control group. All the sections were stained with Toluidine blue and H and E separately. Histopathological analysis was done using binocular light microscope equipped with square ocular grid to standardize the field of evaluation. The result of the study showed. · Significant increase in number of mast cells in oral lichen planus and oral lichenoid mucositis compared to normal buccal mucosa. · Significant increase of intact mast cells suepithelially within the inflammatory cell infiltrate in oral lichen planus compared to oral lichenoid mucositis. · Significant increase of degranulated mast cells in oral lichenoid mucositis to oral lichen planus, and increase in number of eosinophil densities in oral lichenoid mucositis compared to oral lichen planus. · Significant increase in number of capillaries in oral lichenoid mucositis compared to oral lichen planus. The findings of increased number of intact mast cells sub epithelially in oral

  19. In Vitro Lymphocyte Stimulation by Simonsiella in Patients with Oral Lichen Planus

    OpenAIRE

    Sananmuang, K.; Pankhurst, C. L.; Gilkes, J. J. H.; Hardie, J. M.; Ivanyi, L.

    2011-01-01

    The relationship between cell-mediated immunity to sonicated whole cell extract of Simonsiella and lichen planus was investigated in 15 patients with lichen planus, 14 control diseases subjects and 14 controls with healthy oral mucosa by in vitro lymphocyte stimulation. The mean stimulation index was highest in lichen planus group (SI=13.8 ± 2.98), followed by the control diseases group (SI=10.9 ± 2.03) and finally by healthy control group (SI=7.2 ± 1.67). However, there ...

  20. Lichen and bryophyte distribution on oak in London in relation to air pollution and bark acidity

    International Nuclear Information System (INIS)

    Larsen, R.S.; Bell, J.N.B.; James, P.W.; Chimonides, P.J.; Rumsey, F.J.; Tremper, A.; Purvis, O.W.

    2007-01-01

    Epiphytic lichen and bryophyte distribution and frequency were investigated on the trunks of 145 young oak trees throughout London and surrounding counties, and compared with pollution levels and bark pH. Sixty-four lichen and four bryophyte species were recorded. Three major zones were identified: (i) two central regions with a few lichens, bryophytes absent; (ii) a surrounding region with a more diverse flora including a high cover of nitrophyte lichens; and (iii) an outer region, characterised by species absent from central London, including acidophytes. Nineteen species were correlated with nitrogen oxides and 16 with bark pH, suggesting that transport-related pollution and bark acidity influence lichen and bryophyte distribution in London today. Lichens and bryophytes are responding to factors that influence human and environmental health in London. Biomonitoring therefore has a practical role to assess the effects of measures to improve London's air quality. - Transport-related pollutants and bark acidity influence lichen and bryophyte distribution and abundance in London today

  1. 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."

  2. Elemental compositions of lichens from Duolun County, Inner Mongolia, China: Origin, road effect and species difference.

    Science.gov (United States)

    Liu, Hua-Jie; Wang, Jing-Gong; Xia, Yu; Yang, Meng-Jie; Liu, Si-Wa; Zhao, Liang-Cheng; Guo, Xiu-Ping; Jiang, Yun-Jun; Li, Xin; Wu, Qing-Feng; Fang, Shi-Bo

    2017-07-17

    To assess the response of lichen elemental compositions to road traffic and species difference in the context of high dust input and anthropogenic emissions, two foliose epiphytic lichens (Phaeophyscia hirtuosa, PHh; Candelaria fibrosa, CAf) were sampled near a road adjacent to Dolon Nor Town (Duolun County, Inner Mongolia, China). Twenty elements (Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Mo, Na, Ni, P, Pb, Sb, Sr, Ti, V and Zn) in lichen and surface soil samples were analysed using inductively coupled plasma mass spectrometer (ICP-MS). The results demonstrate that lichen elemental compositions are highly influenced by both their natural environment and anthropogenic input. Windblown dust associated with sand dunes and degraded/desertified steppes represents the predominant source of lichen elements. Road traffic can enhance the lichen elemental burden by increasing the number of soil particles. Anthropogenic emissions from the town and road traffic have also led to the enrichment of Cd and Zn in lichens. PHh was higher than CAf in concentrations of 14 terrigenous metals. Both lichens are applicable to biomonitoring of atmospheric element deposition and, in most cases, yield comparable results.

  3. Concurrent Presentation of Erythrodermic Lichen Planus and Squamous Cell Carcinoma: Coincidence or Malignant Transformation?

    Science.gov (United States)

    Ali, Neema M; Bhat, Ramesh; Rao, Shwetha B

    2015-01-01

    Lichen planus is a common papulosquamous disorder affecting about 1-2% of the population, neoplastic transformation of cutaneous lichen planus lesions occurs very rarely. A 40 year old female patient presented with a 1 year history of developing multiple, itchy, pigmented lesions over both lower legs which gradually spread to involve the whole body. A few tense bullae were seen on the extremities. An erythematous fleshy lesion was seen on the upper aspect of the left buttock. Skin biopsy from a plaque on the right forearm showed features suggestive of lichen planus. Skin biopsy of a bullae showed a sub epidermal bulla filled with a mixed inflammatory infiltrate. Direct immunofluorescence revealed no immunoreactants along the basement membrane zone. A diagnosis of erythrodermic lichen planus with bullous lichen planus was made. Biopsy of fleshy lesion of left buttock revealed a moderately differentiated squamous cell carcinoma. Erythrodermic lichen planus with bullous lesions and secondary squamous cell carcinoma; these occurences in a single patient is extremely rare and has not been previously reported to the best of our knowledge.

  4. Air quality lichen monitoring at three selected urban areas in the Southern Serbia

    Directory of Open Access Journals (Sweden)

    Stamenković, S.

    2016-09-01

    Full Text Available The results of a study using epiphytic lichens as bioindicators, on teritory of three different urban areas in the Southern Serbia (Leskovac, Vlasotince, Lebane are reported. The analysis of samples from 142 investigated points indicates presence of 53 lichens taxa. The aim of the study is to present the difference in air quality over a certain time interval. Using the Index of Atmospheric Purity- IAP values, it has been found that there are different air pollution zones: „normal“ zone, „struggle“ zone and „lichen desert“ zone. The comparison of the results obtained in 2002 and 2013 in Vlasotince indicates the presence of „normal“ zone in 2002 but, in 2013, the „normal zone“ area was completely replaced with the „struggle“ zone. In Leskovac, unlike the previous studies, a slightly narrowing “lichen desert" zone is noticed. In Lebane, there is a presence of all lichen zones.

  5. A clitoral verrucous carcinoma in an area of lichen planus has aggressive features.

    Science.gov (United States)

    Tjalma, Wiebren A A; Siozopoulou, Vasiliki; Huizing, Manon T

    2017-01-06

    Verrucous carcinoma of the vulva is extremely rare. It is a slow growing, low malignant variant of a squamous cell carcinoma with a cauliflower appearance. Women with lichen planus have an increased risk of developing vulval cancer. A 79-year-old woman consulted for vulval itching. On clinical examination, a 3-cm large verrucous clitoral cancer in an area of lichen planus was seen. Based on her last clinical examination, the growth was estimated to be 1 cm 2 per month with an invasion depth after 6 months of 5 mm. A tumor developing in an area of lichen planus appears to have more aggressive features. This is the first time that the growth of a verrucous carcinoma has been documented in an area of lichen planus. Clinicians and patients should be aware of the aggressive behavior of cancers developing in areas of lichen planus and adjust their surgical management together with the follow-up strategy.

  6. On monitoring anthropogenic airborne uranium concentrations and 235U/238U isotopic ratio by Lichen - bio-indicator technique

    International Nuclear Information System (INIS)

    Golubev, A.V.; Golubeva, V.N.; Krylov, N.G.; Kuznetsova, V.F.; Mavrin, S.V.; Aleinikov, A.Yu.; Hoppes, W.G.; Surano, K.A.

    2005-01-01

    Lichens are widely used to assess the atmospheric pollution by heavy metals and radionuclides. However, few studies are available in publications on using lichens to qualitatively assess the atmospheric pollution levels. The paper presents research results applying epiphytic lichens as bio-monitors of quantitative atmospheric contamination with uranium. The observations were conducted during 2.5 years in the natural environment. Two experimental sites were used: one in the vicinity of a uranium contamination source, the other one - at a sufficient distance away to represent the background conditions. Air and lichens were sampled at both sites monthly. Epiphytic lichens Hypogimnia physodes were used as bio-indicators. Lichen samples were taken from various trees at about 1.5m from the ground. Air was sampled with filters at sampling stations. The uranium content in lichen and air samples as well as isotopic mass ratios 235 U/ 238 U were measured by mass-spectrometer technique after uranium pre-extraction. Measured content of uranium were 1.45mgkg -1 in lichen at 2.09E-04μgm -3 in air and 0.106mgkg -1 in lichen at 1.13E-05μgm -3 in air. The relationship of the uranium content in atmosphere and that in lichens was determined, C AIR =exp(1.1xC LICHEN -12). The possibility of separate identification of natural and man-made uranium in lichens was demonstrated in principle

  7. 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.

  8. Can partial‐cut harvesting be used to manage terrestrial lichen habitat? A review of recent evidence

    Directory of Open Access Journals (Sweden)

    Susan K. Stevenson

    2015-12-01

    Full Text Available Recent research suggests that partial-cut harvesting techniques can be used to alter successional trajectories in pine- and spruce-lichen woodlands, allowing forest managers to extend the period of reindeer lichen growth in mid- to late seral boreal forest stands. In Quebec, a fully replicated partial-cutting trial found that terrestrial lichen abundance remained at least as high in the partial cut as in the clearcuts or unlogged stands, and that the partial cut appeared to be on a trajectory to have even more terrestrial lichen due to sustained higher growth rates. In Alberta, a retrospective study found higher terrestrial lichen abundance in an early horse-logged partial cut than in undisturbed adjacent old forests or in clearcuts. Follow-up studies of partial-cut harvesting trials in British Columbia found that group selection plots 10 years after harvesting had lichen cover equivalent to that of undisturbed forest. In contrast, studies on lichen woodlands that have been defoliated by mountain pine beetle showed a major decline in reindeer lichen cover and a corresponding increase in vascular plant cover, similar to the results of previous studies on clear-cut logging impacts. Taken together these studies provide qualified support for the hypothesis that partial-cut harvesting can be used to enhance, or at least maintain, terrestrial lichen mats used as forage by caribou.

  9. 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

  10. 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

  11. 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

  12. 210Po and 210Pb in food chains lichen - reindeer - man

    International Nuclear Information System (INIS)

    Solatie, D.; Yunttila, M.; Vesterbakka, P.

    2006-01-01

    Migration of 210 Po and its precursor 210 Pb from radioactive fallout through food chain lichen - reindeer - man is studied. Samples of lichens, leaves, grass, mushrooms, soils, and samples of reindeer tissues are selected; their specific radioactivity and ratio 210 Po/ 210 Pb are determined [ru

  13. Clinico-pathological study to evaluate oral lichen planus for the establishment of clinical and histopathological diagnostic criteria.

    Science.gov (United States)

    Hiremath, Santhosh; Kale, Alka D; Hallikerimath, Seema

    2015-01-01

    Lichen planus and lichenoid lesions affecting the oral cavity show similar clinico-pathological features creating a diagnostic dilemma. Hence, the aim of the present study was to establish a clinical and histopathological correlation in the diagnosis of oral lichen planus, based on the modified WHO diagnostic criteria of oral lichen planus and oral lichenoid lesions proposed by Van der Meij and Van der Waal in 2003. In the present study, 100 cases of oral lichen planus were clinically and histopathologically analyzed. Out of the 100 cases, 50 were prospective and 50 were retrospective cases. Prospective cases were collected based on the clinical diagnosis of oral lichen planus and oral lichenoid lesion. Retrospective cases were collected based on the histopathological diagnosis of oral lichen planus. Both the clinical and histopathological analyses were performed based on a proposal for a set of modified diagnostic criteria of oral lichen planus and oral lichenoid lesion. A final diagnosis of oral lichen planus was made only after the correlation of the clinical diagnosis with the histopathological diagnosis. The interobserver agreement among three observers for both prospective and retrospective cases in the final diagnosis of oral lichen planus was found to be "good" to "very good" indicating high reproducibility. However, the final diagnoses of true oral lichen planus after clinico-pathological correlation in prospective and retrospective study groups appeared to be 38.0% and 54.0% respectively. The results of the present study revealed mild to moderate clinico-pathological correlation in the final diagnosis of oral lichen planus for the prospective and retrospective study groups respectively.

  14. Improving the use of lichens as biomonitors of atmospheric metal pollution

    International Nuclear Information System (INIS)

    Branquinho, C.; Catarino, F.; Brown, D.H.

    2000-01-01

    Improving the use of lichens as biomonitors of atmospheric metal pollution is the main objective of this work. For that a better insight into the availability and location of heavy metals in lichens subjected to polluted conditions both under laboratory and field conditions was attained. The data in this work supported the hypothesis that the absence of the lichen Ramalina fastigiata near a copper mine site, located in the south of Portugal, was related with toxic levels of Cu-dust near the centre of the mine. Lichen biodiversity, measured by the parameter number of lichen species, reflected the impact of the copper-mine dust emissions. The extent of the impact was more widespread towards cast, which appears to be correlated with the frequency of the winds. The chemical analysis of in-situ samples of R. fastigiata collected at different distances and in different directions from the mine showed that Cu, K and Mg were emitted from the centre of the mine site, confirming that major sources of atmospheric dust were located there. Total inhibition of PSII (photosystem II) photochemical reactions occurred in R. fastigiata both under field and controlled conditions, when intracellular Cu concentrations exceeded a threshold of ca. 2.0 μmol g -1 . No samples of this species were found under field conditions beyond the Cu threshold, suggesting that the absence of the lichen R. fastigiata might be used as an indicator of intracellular Cu concentrations above 2.0 μmol g -1 in the surroundings of the copper-mine. The fluorescence parameter F v /F m proved to be a good estimator of the survival capacity of R. fastigiata under field conditions and thus a useful parameter in determining the sensitivity of the lichens (photobiont) to Cu pollution. The intracellular location of Cu, K and Mg allowed to explain the physiological changes and the survival of the species in the surroundings of the copper-mine. (author)

  15. Estimating Coextinction Risks from Epidemic Tree Death: Affiliate Lichen Communities among Diseased Host Tree Populations of Fraxinus excelsior

    Science.gov (United States)

    Jönsson, Mari T.; Thor, Göran

    2012-01-01

    At least 10% of the world’s tree species are threatened with extinction and pathogens are increasingly implicated in tree threats. Coextinction and threats to affiliates as a consequence of the loss or decline of their host trees is a poorly understood phenomenon. Ash dieback is an emerging infectious disease causing severe dieback of common ash Fraxinus excelsior throughout Europe. We utilized available empirical data on affiliate epiphytic lichen diversity (174 species and 17,800 observations) among 20 ash dieback infected host tree populations of F. excelsior on the island Gotland in the Baltic Sea, Sweden. From this, we used structured scenario projections scaled with empirical data of ash dieback disease to generate probabilistic models for estimating local and regional lichen coextinction risks. Average coextinction probabilities (Ā) were 0.38 (95% CI ±0.09) for lichens occurring on F. excelsior and 0.14 (95% CI ±0.03) when considering lichen persistence on all tree species. Ā was strongly linked to local disease incidence levels and generally increasing with lichen host specificity to F. excelsior and decreasing population size. Coextinctions reduced affiliate community viability, with significant local reductions in species richness and shifts in lichen species composition. Affiliates were projected to become locally extirpated before their hosts, illuminating the need to also consider host tree declines. Traditionally managed open wooded meadows had the highest incidence of ash dieback disease and significantly higher proportions of affiliate species projected to go extinct, compared with unmanaged closed forests and semi-open grazed sites. Most cothreatened species were not previously red-listed, which suggest that tree epidemics cause many unforeseen threats to species. Our analysis shows that epidemic tree deaths represent an insidious, mostly overlooked, threat to sessile affiliate communities in forested environments. Current conservation and

  16. Investigations on carotenoids in lichens. XXXII. Carotenoids occurring in the thalli of lichens from Kenya (Equatorial Africa

    Directory of Open Access Journals (Sweden)

    Bazyli Czeczuga

    2014-01-01

    Full Text Available The presence of cartenoids in nineteen species of lichens from Kenya (Equatorial Africa was studied by column and thinlayer chromatography. This investigations revealed the presence of the following carotenoids: neurosporene, α-carotene, β-carotene, rubixanthin, α-cryptoxanthin, β-cryptoxanthin, zeaxanthin, lutein, 3'-epilutein, torularhodin, diatoxanthin, neoxanthin, echinenone, 3'-hydroxyechinenone, canthaxanthin, α-doradexanthin, astaxanthin, β-carotene epoxide, antheraxanthin, lutein epoxide, violaxanthin, mutatoxanthin, flavoxanthin, capsochrome, β-apo-8'-carotenal, β-apo-10'-carotenal and apo-12'-violaxanthal. Five of these, torularhodin, 3'-hydroxyechinenone, capsochrome, β-apo-8'-carotenal and β-apo-10'-carotenal, are reported for the first time from lichens. The total carotenoid content of the material ranged from 15.88 (Pyxine cocoes to 135.44 µg g-1 dry weight (Telaschistes chrysophthalmus.

  17. 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

  18. 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.

  19. The importance of the Gonidia to the classification of the Lichens

    NARCIS (Netherlands)

    Nannenga, E.T.

    1939-01-01

    More than 70 years have elapsed, since, in 1866, de Bary enunciated the hypothesis that Lichens are dual organisms, the socalled gonidia being Algae. As about 1899, the year when Nylander died, the dual nature of the Lichens had become generally accepted, lichenologists have had 40 years to realize

  20. 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

  1. 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

  2. Lichen density on bark of Populus tremula affected by industrial smoke emission. [Xanthoria; Parmelia; Physcia; Caloplaca; Lecanora

    Energy Technology Data Exchange (ETDEWEB)

    Sundstrom, E W

    1973-01-01

    To get a quantitative view of the damage to lichens by industrial smoke emissions, the author has measured the percentage of area covered by lichens on mature aspens, diameter 200-400 mm, between 1 and 2 m above ground. 500 trees in 130 locations in central Gaestrikland were studied. A marked reduction in lichen cover is noticeable up to 10-15 km from the emission points. No difference in sensitivity between the most common lichens was noted. Proximity to lakes or plowed fields seems to counteract the smoke effect. Lichens on other trees are less sensitive to the smoke. Main roads and non-industrial settlements have no influence on the lichens treated here. 2 references, 1 figure.

  3. Case Report: Dermoscopic features of oral lichen planus - the evolution of mucoscopy.

    Science.gov (United States)

    Sonthalia, Sidharth; Varma, Sangeeta; Jha, Abhijeet Kumar; Jakhar, Deepak; Kaliyadan, Feroze

    2018-01-01

    Dermoscopy, a non-invasive technique for cutaneous diagnosis is being increasingly studied in various disorders of the skin, nails and scalp. However, it has been under-utilized for the diagnosis and characterization of mucosal disorders. The dermoscopic characterization of cutaneous lichen planus and its variants has been well documented with Wickham's striae constituting the hallmark of the condition. However, the dermoscopic features of oral lichen planus with hand-held or videodermoscopy remain to be elucidated. We present the case of a young adult man who presented with asymptomatic white lacy lesions over a bluish-black background over the tongue, patchy hyperpigmentation of the buccal mucosae and gingivae, and longitudinal melanonychia involving some nails. History of intake of any drugs preceding the lesions, smoking, chewing of betel nut and dental implants was negative. Family history was non-contributory. There were no cutaneous lesions suggestive of lichen planus. Mucoscopy (dermoscopy of the mucosa, oral in this case) and onychoscopy were done followed by biopsy from the tongue that confirmed the diagnosis of lichen planus. Oral mucoscopy of the tongue revealed a tri-colored pattern with structureless veil-like grey-white areas (modified Wickham's striae), well-demarcated red glossy erosions, and violaceous-to-brown clods. Additionally, vascular pattern of dotted and linear to curved vessels along the borders of leukoplakia-like areas and erosions were observed. Onychoscopy confirmed lichen planus-associated melanonychia. Dermoscopy also proved useful in conveniently ruling out other disorders typified by mucosal and nail pigmentation such as Laugier Hunziker syndrome and drug-induced changes. Although direct oral microscopy has been used in defining features of oral lichen planus, to the best of our knowledge this case is the first report on mucoscopy or dermoscopy of oral lichen planus.

  4. Lupus erythematosus/lichen planus overlap syndrome: successful treatment with acitretin.

    Science.gov (United States)

    Lospinoso, D J; Fernelius, C; Edhegard, K D; Finger, D R; Arora, N S

    2013-07-01

    Lupus erythematosus/lichen planus overlap syndrome is a rare disorder combining the clinical, histological and immunopathological features of both lupus erythematosus (LE) and lichen planus (LP). Cutaneous lesions mostly affect the distal arms, legs, face and trunk. Palmoplantar involvement is felt to be characteristic of this condition. Plaques are often painful, centrally atrophic, bluish-red to hypopigmented in color, large, and scaly. On biopsy of clinically ambiguous lesions, histopathological features of one or both processes can be found, obscuring the diagnosis and complicating prognosis and treatment. Thus, direct immunofluorescence has become an essential tool in helping to diagnose this condition. In this report we describe the unique clinical and immunohistopathological manifestations of lupus erythematosus/lichen planus overlap syndrome along with a successful response to treatment with acitretin.

  5. Bryophyte and lichen indicators of air pollution in Christchurch, New Zealand

    Energy Technology Data Exchange (ETDEWEB)

    Daly, G T

    1970-01-01

    In the winters of 1968 and 1969 a survey was made of the growth and distribution of bryophyte and lichen species within communities on tree trunks, stone walls, nonmetallic roofs and soil in Christchurch, New Zealand. The survey was stimulated by European and Scandinavian work which has shown that high levels of urban and industrial air pollution have caused severe reductions in the distribution of normally-abundant cryptogams. The present survey has demonstrated that a similar, but at present less severe, reduction in bryophyte and lichen flora occurs in Christchurch. Removal of sensitive species through their inability to grow at even moderate levels of winter pollution is considered the most likely cause. An initial transplant experiment indicates that damage to sensitive mosses like Hypnum and Brachythecium may occur within 3 months of exposure to city air. Gilbert and others have shown that in northern England sensitive mosses and lichens begin to die when the average winter sulphur dioxide level reaches 50 ..mu..g/m/sup 3/ of air. This relationship has been confirmed in Christchurch, a moderately polluted city. Numbers of species and the area covered by sensitive mosses, hepatics and lichens reduce sharply along a broad transect into the centre of Christchurch from the west. Further work should display the distribution patterns of sensitive species. However, the information reported here demonstrates the possibility of using changes in selected mosses and lichens to indicate the trends in winter sulphur dioxide pollution in the city. Many of the genera and species of bryophytes and lichens prominent in the English survey were also found to be common in Christchurch. Introduction on plants and building materials during colonial times is considered likely.

  6. On accumulation of 90Sr and 137Cs by some lower plants in the vicinity of the Beloyarsky atomic power station in the Urals

    International Nuclear Information System (INIS)

    Nifontova, M.G.; Kulikov, N.V.

    1981-01-01

    The data are given on the content of 90 Sr and 137 Cs in thalluses of the foliose epiphytic lichen Hypogymnia physodes (L) and in a number of the most widely distributed in nature edxble fungi that grow in the forests of the sanitary-protective zone of the Beloyarsk nuclear power station in the Middle Urals: russula-Russula cyaxantha (Schw)Fr; brown cap boletus-Leccinum scabrum (Fe)S.F.Gray, milk-agaric-Lactarius resimus Fr., russula-Russula foetens (Fr.)Fr. It has been ascertained that the concentration of 90 Sr and 137 Cs in epiphytic lichens and edible agaric fungi in the vicinity of the Beloyarsk nuclear power station does not exceed the background content of these radionuclides characteristic of analogous plants in other locations outside the range of a possible effect of the nuclear power station [ru

  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. Lichens as an integrating tool for monitoring PAH atmospheric deposition: A comparison with soil, air and pine needles

    International Nuclear Information System (INIS)

    Augusto, Sofia; Maguas, Cristina; Matos, Joao; Pereira, Maria Joao; Branquinho, Cristina

    2010-01-01

    The aim of this study was to validate lichens as biomonitors of PAH atmospheric deposition; for that, an inter-comparison between the PAH profile and concentrations intercepted in lichens with those of air, soil and pine needles was performed. The study was conducted in a petro-industrial area and the results showed that PAH profiles in lichens were similar to those of the air and pine needles, but completely different from those of soils. Lichens accumulated higher PAH concentrations when compared to the other environmental compartments and its concentrations were significantly and linearly correlated with concentrations of PAHs in soil; we showed that a translation of the lichen PAHs concentrations into regulatory standards is possible, fulfilling one of the most important requirements of using lichens as biomonitors. With lichens we were then able to characterize the air PAHs profile of urban, petro-industrial and background areas. - Lichen PAH concentrations can identify geographic areas that may be out of compliance with regulatory standards.

  9. 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 ...

  10. Lichens as biomonitors around a coal-fired power station in Israel

    International Nuclear Information System (INIS)

    Garty, Jacob; Tomer, Sharon; Levin, Tal; Ehr, Haya

    2003-01-01

    In the present study epiphytic lichens were applied as biomonitors of air pollution to determine the environmental impact of a coal-fired power station. Thalli of the lichen Ramalina lacera (With.) J.R. Laund. growing on carob twigs (Ceratonia siliqua L.) were collected with their substrate in July 2000 in a relatively unpolluted forest near HaZorea, Ramoth Menashe, ortheast Israel, and transplanted to 10 biomonitoring sites in the vicinity of the coal-fired power station Oroth Rabin near the town of Hadera. The lichens were retrieved in January 2001. We examined the following parameters of lichen vitality: (a) potential quantum yield of photosynthesis expressed as fluorescence ratio F v /F m , (b) stress-ethylene production, and (c) electric conductivity expressing integrity of cell membranes. Following an exposure of 7 months, the lichens were retrieved and physiological parameters and data of elemental content were analyzed comparatively. Electric conductivity values correlated positively with B, Fe, Mg, Mn, Na, Pb, S, Sn, nd Ti content. Concentrations of stress-ethylene correlated positively with l, Ba, Pb, S, and V content and negatively with Cu and Sn. F v /F m ratios correlated negatively with S content. Some of the heavy metals reached lower levels than those reported in the relevant literature despite a wind regime that should have blown pollutants toward the biomonitoring sites

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  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. Sleep disturbances, anxiety and depression in patients with oral lichen planus: a case-control study.

    Science.gov (United States)

    Adamo, D; Ruoppo, E; Leuci, S; Aria, M; Amato, M; Mignogna, M D

    2015-02-01

    The psychological factors and their association with chronic inflammatory disease, aren't well recognized, yet their importance in oral lichen planus is still debated. The aim of this study was to investigate the prevalence of sleep disturbances, anxiety, depression and their association in patient with oral lichen planus. 50 patients with oral lichen planus vs. equal number of age and sex-matched healthy controls were enrolled. Questionnaires examining insomnia symptoms, excessive daytime sleepiness (Pittsburgh sleep quality index and Epworth aleepiness scale) depression and anxiety (The Hamilton rating scale for Depression and Anxiety) were used. The patients with oral lichen planus had statistically higher scores in all items of the Pittsburgh sleep quality index, the Hamilton rating scale for depression and anxiety and Epworth sleepiness scale than the healthy controls. The median and inter-quartile range of the Pittsburgh sleep quality index was 5-2 and for the oral lichen planus patients and 4-2 for the healthy controls (P Oral lichen planus patients report a greater degree of sleep problems, depressed mood and anxiety as compared with controls. We suggest to screen sleep disturbances in patients with oral lichen planus because they could be considered a prodromal symptoms of mood disorders. © 2014 European Academy of Dermatology and Venereology.

  17. 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.

  18. Metabolomic Analysis of Two Parmotrema Lichens: P. robustum (Degel. Hale and P. andinum (Mull. Arg. Hale Using UHPLC-ESI-OT-MS-MS

    Directory of Open Access Journals (Sweden)

    Alfredo Torres-Benítez

    2017-10-01

    Full Text Available Lichens are symbiotic associations of fungi with microalgae and/or cyanobacteria. Lichens belonging to the Parmeliaceae family comprise 2700 species of lichens, including the Parmotrema genus which is composed of 300 species. The metabolites of this genus include depsides, depsidones, phenolics, polysaccharides, lipids, diphenylethers and dibenzofurans, which are responsible for the biological activities reported including antidiabetic, antihelmintic, anticancer, antioxidant, antibacterial, anti-inflammatory, antimitotic, antitumoral, antifungal, and antioxidant enzyme inhibitory. Due to scarce knowledge of metabolomic profiles of Parmotrema species (P. andinum and P. robustum, a full metabolome study based on ultra-high performance liquid chromatography- diode array detector-electrospray ionization-quadrupole-orbitrap-mass-spectrometry (UHPLC-DAD-ESI-Q-orbitrap MS was performed for a comprehensive characterization of their substances. From the methanolic extracts of these species, a total of 54 metabolites were identified for the first time using this hyphenated technique, including thirty compounds in P. andinum, and thirty-seven in P. robustum. Moreover, two compounds were not identified as known compounds, and could be new structures, according to our data. This report shows that this technique is effective and accurate for rapid chemical identification of lichen substances and the compounds identified could serve as chemotaxonomic markers to differentiate these ruffle lichens.

  19. Forests Regenerating after Clear-Cutting Function as Habitat for Bryophyte and Lichen Species of Conservation Concern

    Science.gov (United States)

    Rudolphi, Jörgen; Gustafsson, Lena

    2011-01-01

    The majority of managed forests in Fennoscandia are younger than 70 years old but yet little is known about their potential to host rare and threatened species. In this study, we examined red-listed bryophytes and lichens in 19 young stands originating from clear-cutting (30–70 years old) in the boreal region, finding 19 red-listed species (six bryophytes and 13 lichens). We used adjoining old stands, which most likely never had been clear-cut, as reference. The old stands contained significantly more species, but when taking the amount of biological legacies (i.e., remaining deciduous trees and dead wood) from the previous forest generation into account, bryophyte species number did not differ between old and young stands, and lichen number was even higher in young stands. No dispersal effect could be detected from the old to the young stands. The amount of wetlands in the surroundings was important for bryophytes, as was the area of old forest for both lichens and bryophytes. A cardinal position of young stands to the north of old stands was beneficial to red-listed bryophytes as well as lichens. We conclude that young forest plantations may function as habitat for red-listed species, but that this depends on presence of structures from the previous forest generation, and also on qualities in the surrounding landscape. Nevertheless, at repeated clear-cuttings, a successive decrease in species populations in young production stands is likely, due to increased fragmentation and reduced substrate amounts. Retention of dead wood and deciduous trees might be efficient conservation measures. Although priority needs to be given to preservation of remnant old-growth forests, we argue that young forests rich in biological legacies and located in landscapes with high amounts of old forests may have a conservation value. PMID:21490926

  20. The development of proliferative verrucous leukoplakia in oral lichen planus. A preliminary study

    Science.gov (United States)

    Llorente-Pendás, Santiago; González-Garcia, Manuel; García-Martín, José-Manuel

    2016-01-01

    Background Was to describe 14 cases of a proliferative verrucous leukoplakia as a clinical evolution of oral lichen planus. Material and Methods The clinical and histopathological characteristics of 14 cases of OLP that progress towards a plaque-like and verrucous form were indicated, with monitoring over a period of six to 24.3 years. Results The female/male ratio was 11/3, (78.6 and 21.4%). The mean age when the first biopsy was undertaken was 56.4 years old. None of the patients smoked during the study. As bilateral reticular was clinically diagnostic criterion, the second most frequent clinical form was the plaque form (n=10; 71.4%), followed by the atrophic (n=6; 42.8%), and erosive forms (n=4; 28.5%). Clinically it spread towards attached gingival mucosa and the hard palate. In the histopathologic study, there were a predominance of hyperkeratosis and verrucous epithelial hyperplasia. Three of the cases progressed to a squamous cell carcinoma, and one patient developed two verrucous carcinoma. Conclusions Further research is needed to demonstrate if proliferative multifocal oral lichen planus and proliferative multifocal oral leukoplakia are the same disorder but have different behaviour of malignancy for reasons of origin. Key words:Oral lichen planus, proliferative verrucous oral leukoplakia, malignant oral lichen planus, multifocal verrucous oral lichen planus, proliferative verrucous oral lichen planus. PMID:27031060

  1. Exposure of lichens for the recognition and the evaluation of air pollutants

    Energy Technology Data Exchange (ETDEWEB)

    Schoenbeck, H; Van Haut, H

    1971-01-01

    Lower and higher plants can be used as biological indicators to evaluate air quality. Both field and fumigation experiments have proven that the lichen Parmelia physodes is measurably influenced by sulfur dioxide, hydrogen fluoride and hydrogen chloride. A distinct relationship was found between the dose of a toxicant and the death rate. Development of methods of exposing these lichens in polluted areas and of determining their reactions made it possible to use these organisms as a biological measuring procedure. The death rate within a certain period of time is used as an effect criterion, and serves as a measure. By means of different examples it is demonstrated that lichens can be used for monitoring air pollution in both small and large areas. The use of lichens as indicators for toxicants in air can lead to a simple and inexpensive method of monitoring air pollutants.

  2. 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)

  3. 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).

  4. [Diversity of Bacillus species inhabiting on the surface and endophyte of lichens collected from Wuyi Mountain].

    Science.gov (United States)

    Ge, Cibin; Liu, Bo; Che, Jianmei; Chen, Meichun; Liu, Guohong; Wei, Jiangchun

    2015-05-04

    The present work reported the isolation, identification and diversity of Bacillus species colonizing on the surface and endophyte in lichens collected from Wuyi Mountain. Nine lichen samples of Evernia, Stereocaulon, Menegazzia and other 6 genera belonging to 7 families were collected from Wuyi mountain nature reserve. The bacillus-like species colonizing on the surface and endophyte in these lichens were isolated and identified by 16S rRNA gene sequence analysis. There was no bacillus-like species isolated from Evernia, Ramalina and Lecarona. A total of 34 bacillus-like bacteria were isolated from another 6 lichen samples. These bacteria were identified as 24 species and were classified into Bacillus, Paenibacillus, Brevibacillus, Lysinibacillus and Viridiibacillus. Paenibacillus and Bacillus are the dominant genera, and accounting for 41. 2% and 35. 3% of all isolated bacteria respectively. Brevibacillus, Lysinibacillus and Viridiibacillu were first reported being isolated from lichens. There were different species and quantity of bacillus colonizing on the surface and endophyte in different lichens. The quantity of bacillus colonizing on the surface of Physcia was more than 3.85 x 10(6) cfu/g and was the largest in the isolated bacteria, while the species of bacillus colonizing on the surface and endophyte in Stereocaulon was the most abundant. Most of the isolated bacteria were colonizing on (in) one lichen genera, but Paenibacillus taichungensis, Paenibacillus odorifer, Brevibacillus agri, Lysinibacillus xylanilyticus was respectively colonizing on (in) 2-3 lichen genera and Bacillus mycoides was colonizing on (in) Menegazzia, Cladonia Physcia, and Stereocaulon. There are species and quantity diversity of bacillus colonizing on (in) lichens.

  5. Forest Type and Tree Characteristics Determine the Vertical Distribution of Epiphytic Lichen Biomass in Subtropical Forests

    Directory of Open Access Journals (Sweden)

    Su Li

    2017-11-01

    Full Text Available Epiphytic lichens are an important component in subtropical forests and contribute greatly to forest biodiversity and biomass. However, information on epiphytic lichens still remains scarce in forest conservation owing to the difficulty of accessing all canopy layers for direct observation. Here, epiphytic lichens were quantified on 73 whole trees in five forest types in Southwest China to clarify the vertical stratification of their biomass in subtropical forests. Lichen biomass was significantly influenced by forest type and host attributes, varying from 187.11 to 8.55 g∙tree−1 among forest types and from 289.81 to <0.01 g∙tree−1 among tree species. The vertical stratification of lichen biomass was also determined by forest type, which peaked at the top in primary Lithocarpus forest and middle-aged oak secondary forest and in the middle upper heights in other forests. Overall, the proportion of lichen biomass accounted for 73.17–100.00% of total lichen biomass on branches and 0.00–26.83% on trunks in five forests, and 64.53–100.00% and 0.00–35.47% on eight host species. Seven functional groups showed marked and various responses to tree height between and among forest types. This information improves our understanding of the distribution of epiphytic lichens in forest ecosystems and the promotion of forest management in subtropical China.

  6. Global estimate of lichen and bryophyte contributions to forest precipitation interception

    Science.gov (United States)

    Van Stan, John; Porada, Philipp; Kleidon, Axel

    2017-04-01

    Interception of precipitation by forest canopies plays an important role in its partitioning to evaporation, transpiration and runoff. Field observations show arboreal lichens and bryophytes can substantially enhance forests' precipitation storage and evaporation. However, representations of canopy interception in global land surface models currently ignore arboreal lichen and bryophyte contributions. This study uses the lichen and bryophyte model (LiBry) to provide the first process-based modelling approach estimating these organisms' contributions to canopy water storage and evaporation. The global mean value of forest water storage capacity increased significantly from 0.87 mm to 1.33 mm by the inclusion of arboreal poikilohydric organisms. Global forest canopy evaporation of intercepted precipitation was also greatly enhanced by 44%. Ratio of total versus bare canopy global evaporation exceeded 2 in many forested regions. This altered global patterns in canopy water storage, evaporation, and ultimately the proportion of rainfall evaporated. A sensitivity analysis was also performed. Results indicate rainfall interception is of larger magnitude than previously reported by global land surface modelling work because of the important role of lichen and bryophytes in rainfall interception.

  7. Contrasting patterns in lichen diversity in the continental and maritime Antarctic

    Science.gov (United States)

    Singh, Shiv Mohan; Olech, Maria; Cannone, Nicoletta; Convey, Peter

    2015-09-01

    Systematic surveys of the lichen floras of Schirmacher Oasis (Queen Maud Land, continental Antarctic), Victoria Land (Ross Sector, continental Antarctic) and Admiralty Bay (South Shetland Islands, maritime Antarctic) were compared to help infer the major factors influencing patterns of diversity and biogeography in the three areas. Biogeographic patterns were determined using a variety of multivariate statistical tools. A total of 54 lichen species were documented from Schirmacher Oasis (SO), 48 from Victoria Land (VL) and 244 from Admiralty Bay (AB). Of these, 21 species were common to all areas. Most lichens from the SO and VL areas were microlichens, the dominant genus being Buellia. In AB, in contrast, many macrolichens were also present and the dominant genus was Caloplaca. In SO and VL large areas lacked any visible lichen cover, even where the ground was snow-free in summer. Small-scale diversity patterns were present in AB, where the number of species and genera was greater close to the coast. Most species recorded were rare in the study areas in which they were present and endemic to Antarctica.

  8. Identification of most tolerant lichen species to vehicular traffic's pollutants at Batu Pahat area

    Science.gov (United States)

    Khairuddin, Nur Ain; Muhammad, Norhayati; Hashim, Nor Haslina; Yusof, Hasliza; Jusoh, Samsiah; Abas, Azlan; Talip, Balkis A.; Abdullah, Norazlin; Din, Laily B.

    2017-10-01

    Bio-indicators are organisms that can be used for the identification and qualitative determination of human generated environmental factors. The decreasing population of sensitive lichens in specific regions around the world due to low air quality level has make lichens as a bio-indicator for air pollution. Lichen is a result of symbiotic association of fungus and alga and well known for having wide variety of sensitivity towards environmental stressors such as air quality and climate change. The aim of this study is to identify the most tolerant lichen species to vehicular traffic's pollutant at Batu Pahat urban and suburban areas. This study was conducted by using Index of Atmospheric Purity (IAP) method and followed by morphological and chemicals testing for species identification. Dirinaria picta has been identified as the most tolerant lichen species against pollutants from vehicle traffic. The results also indicated that the air quality of Batu Pahat town/urban area could be considered as moderately clean.

  9. Elemental levels in tree-bark and epiphytic-lichen transplants at a mixed environment in mainland Portugal, and comparisons with an in situ lichen

    Energy Technology Data Exchange (ETDEWEB)

    Pacheco, A.M.G. [CERENA-IST, Technical University of Lisbon, Av. Rovisco Pais 1, 1049-001 Lisbon (Portugal)], E-mail: apacheco@ist.utl.pt; Freitas, M.C. [Reactor-ITN, Technological and Nuclear Institute, E.N. 10, 2686-953 Sacavem (Portugal); Baptista, M.S. [CIIMAR, University of Porto, R. dos Bragas 289, 4050-123 Porto (Portugal); Vasconcelos, M.T.S.D. [CIIMAR, University of Porto, R. dos Bragas 289, 4050-123 Porto (Portugal); Chemistry Department, University of Porto, R. do Campo Alegre 687, 4169-071 Porto (Portugal); Cabral, J.P. [CIIMAR, University of Porto, R. dos Bragas 289, 4050-123 Porto (Portugal); Botany Department, University of Porto, R. do Campo Alegre 1191, 4150-181 Porto (Portugal)

    2008-01-15

    Samples of Platanus hybrida Brot. bark and Flavoparmelia caperata (L.) Hale thalli, from a clean area in northern Portugal (Baiao), were transplanted into an exposure location at the south-western Atlantic coast, impacted by urban-industrial emissions (Sines), for a 10-month long experiment. Bark pieces were confined into nylon bags (2-mm mesh), and lichen thalli kept with their bark substrate (Pinus pinaster (Ait.) Sol.). Every two months, a double set of transplants (one for bark, one for lichens) was brought back into the laboratory, together with native samples of Evernia prunastri (L.) Ach. Following suitable cleansing and preparation procedures, field samples were put through INAA for elemental assessment. The results indicate that, regardless of signal magnitude, (1) concentrations in bark and lichen transplants are significantly correlated with atmospheric deposition for an appreciable number of elements; (2) there are a number of significant correlations between transplanted and native samples, and again between the latter and the deposition; and (3) the elements with biological patterns that follow the deposition in either transplanted or native samples (Co, V) are the very ones whose bioaccumulation seems to benefit from an alternation of wet-dry periods, which fits the precipitation record of the test site during the exposure term. - Depending on the element(s) of interest, native lichens can replace transplants for temporal (short-term) atmospheric assessment.

  10. Elemental levels in tree-bark and epiphytic-lichen transplants at a mixed environment in mainland Portugal, and comparisons with an in situ lichen

    International Nuclear Information System (INIS)

    Pacheco, A.M.G.; Freitas, M.C.; Baptista, M.S.; Vasconcelos, M.T.S.D.; Cabral, J.P.

    2008-01-01

    Samples of Platanus hybrida Brot. bark and Flavoparmelia caperata (L.) Hale thalli, from a clean area in northern Portugal (Baiao), were transplanted into an exposure location at the south-western Atlantic coast, impacted by urban-industrial emissions (Sines), for a 10-month long experiment. Bark pieces were confined into nylon bags (2-mm mesh), and lichen thalli kept with their bark substrate (Pinus pinaster (Ait.) Sol.). Every two months, a double set of transplants (one for bark, one for lichens) was brought back into the laboratory, together with native samples of Evernia prunastri (L.) Ach. Following suitable cleansing and preparation procedures, field samples were put through INAA for elemental assessment. The results indicate that, regardless of signal magnitude, (1) concentrations in bark and lichen transplants are significantly correlated with atmospheric deposition for an appreciable number of elements; (2) there are a number of significant correlations between transplanted and native samples, and again between the latter and the deposition; and (3) the elements with biological patterns that follow the deposition in either transplanted or native samples (Co, V) are the very ones whose bioaccumulation seems to benefit from an alternation of wet-dry periods, which fits the precipitation record of the test site during the exposure term. - Depending on the element(s) of interest, native lichens can replace transplants for temporal (short-term) atmospheric assessment

  11. Epiphytic lichen Flavoparmelia caperata as a sentinel for trace metal pollution

    Directory of Open Access Journals (Sweden)

    Mitrović Tatjana

    2012-01-01

    Full Text Available Widely spread lichen specie Flavoparmelia caperata is used in a biomonitoring study for atmospheric trace metal pollution in natural ecosystems in Southeastern Serbia. The concentration and distribution pattern of 21 metals in lichens were determined by inductively coupled plasma atomic emission spectrometry. The difference observed between metal deposition in peripheral and central parts of lichen thalli reflected air quality changes in the last and previous years. These findings were confirmed with principal component analysis. Our study demonstrated the accumulation of Ba, K, Mg, Na, Tl and Zn in peripheral parts of thalli, while As, B, Cd, Cr, Cu, Fe, Ga, In, Li, Ni, Pb and Se were concentrated in central parts of thalli.

  12. Application of the autoradiography method for study of the Semipalatinsk test site's lichens

    International Nuclear Information System (INIS)

    Ajdarkhanova, G.S.; Poltavtseva, V.P.

    2003-01-01

    The preliminary results of the Semipalatinsk test site's lichens study with help of the autoradiography method are presented. The lichens selected in 1999 on the experimental sites situated in two areas (20 km southerly from Kurchatov town and on of the Degelen mountain south side) have served as the examined objects. Radiation background of the lichens dwelling areas make up 15-17 and 300 μR/h respectively. For receiving of autoradiograms the FT-41MD film with two-side emulsion layer was used. Exposition time is 48 and 744 hours. From visual analysis of photographic image with this autoradiogram one can draw the conclusion about uniform distribution of the radionuclides. Received results testify about the necessity for continuance of the researches in this direction with expansion lichen species content and geography of their scattering

  13. Lichen forage ingestion rates of free-roaming caribou estimated with fallout cesium-137

    International Nuclear Information System (INIS)

    Hanson, W.C.; Whicker, F.W.; Lipscomb, J.F.

    1975-01-01

    Lichen forage ingestion rates of free-roaming caribou herds in northern Alaska during 1963 to 1970 were estimated by applying a two-compartment, eight parameter cesium-137 kinetics model to measured fallout 137 Cs concentrations in lichen and caribou. Estimates for winter equilibrium periods (January to April) for each year ranged from 3.7 to 6.9 kg dry weight lichens per day for adult female caribou. Further refinement of these estimations were obtained by calculating probabilistic distributions of intake rates by stochastic processes based upon the mean and standard error intervals of the eight parameters during 1965 and 1968. A computer program generated 1,000 randomly sampled values within each of the eight parameter distributions. Results substantiate the contention that lichen forage ingestion rates by free-roaming caribou are significantly greater than previously held

  14. Experimental climate warming decreases photosynthetic efficiency of lichens in an arid South African ecosystem.

    Science.gov (United States)

    Maphangwa, Khumbudzo Walter; Musil, Charles F; Raitt, Lincoln; Zedda, Luciana

    2012-05-01

    Elevated temperatures and diminished precipitation amounts accompanying climate warming in arid ecosystems are expected to have adverse effects on the photosynthesis of lichen species sensitive to elevated temperature and/or water limitation. This premise was tested by artificially elevating temperatures (increase 2.1-3.8°C) and reducing the amounts of fog and dew precipitation (decrease 30.1-31.9%), in an approximation of future climate warming scenarios, using transparent hexagonal open-top warming chambers placed around natural populations of four lichen species (Xanthoparmelia austroafricana, X. hyporhytida , Xanthoparmelia. sp., Xanthomaculina hottentotta) at a dry inland site and two lichen species (Teloschistes capensis and Ramalina sp.) at a humid coastal site in the arid South African Succulent Karoo Biome. Effective photosynthetic quantum yields ([Formula: see text]) were measured hourly throughout the day at monthly intervals in pre-hydrated lichens present in the open-top warming chambers and in controls which comprised demarcated plots of equivalent open-top warming chamber dimensions constructed from 5-cm-diameter mesh steel fencing. The cumulative effects of the elevated temperatures and diminished precipitation amounts in the open-top warming chambers resulted in significant decreases in lichen [Formula: see text]. The decreases were more pronounced in lichens from the dry inland site (decline 34.1-46.1%) than in those from the humid coastal site (decline 11.3-13.7%), most frequent and prominent in lichens at both sites during the dry summer season, and generally of greatest magnitude at or after the solar noon in all seasons. Based on these results, we conclude that climate warming interacting with reduced precipitation will negatively affect carbon balances in endemic lichens by increasing desiccation damage and reducing photosynthetic activity time, leading to increased incidences of mortality.

  15. Salivary Total Antioxidant Capacity and Lipid Peroxidation in Patients with Erosive Oral Lichen Planus

    Directory of Open Access Journals (Sweden)

    Atena Shirzad

    2014-03-01

    Full Text Available Background and aims. Oral lichen planus is a common chronic inflammatory disease of the oral mucosa with malignant potential, pathogenesis of which is not still well known. Free radicals and reactive oxygen species can play an important role in the pathogenesis of oral lichen planus. The aim of this study was to investigate salivary oxidative stress and antioxidant systems in patients with oral lichen planus. Materials and methods. In this case-control study, 30 patients with oral lichen planus (case group and 30 age- and gender-matched healthy subjects (control group, referring to Dental School of Babol University of Medical Sciences, were selected using simple sampling method. Unstimulated saliva of the two groups was collected. Salivary total antioxidant capacity (TAC and lipid peroxidation products were investigated and compared, using ferric reducing antioxidant power (FRAP and thiobarbituric acid reactive substance (TBARS methods, respectively. Data were analyzed using Student’s ttest. Results. The mean and standard deviation of salivary TAC in patients with oral lichen planus (297.23 ± 149.72 μM was significantly lower than that in the controls (791.43±183.95 μM; P < 0.0001, and mean and standard deviation of salivary malondialdehyde (MDA (0.49 ± 0.30 μM was remarkably higher in oral lichen planus patients compared to the control group (0.15 ± 0.11 μM (P < 0.0001. TAC was also reduced in both groups in line with an increase in the level of MDA (P < 0.0001, r = −0.48. Conclusion. The results of this study suggested that an increase in oxidative stress and an imbalance in antioxidant defense system in the saliva of oral lichen planus patients may be involved in the pathogenesis of oral lichen planus.

  16. Salivary total antioxidant capacity and lipid peroxidation in patients with erosive oral lichen planus.

    Science.gov (United States)

    Shirzad, Atena; Pouramir, Mahdi; Seyedmajidi, Maryam; Jenabian, Niloofar; Bijani, Ali; Motallebnejad, Mina

    2014-01-01

    Background and aims. Oral lichen planus is a common chronic inflammatory disease of the oral mucosa with malignant potential, pathogenesis of which is not still well known. Free radicals and reactive oxygen species can play an important role in the pathogenesis of oral lichen planus. The aim of this study was to investigate salivary oxidative stress and antioxidant systems in patients with oral lichen planus. Materials and methods. In this case-control study, 30 patients with oral lichen planus (case group) and 30 age-and gender-matched healthy subjects (control group), referring to Dental School of Babol University of Medical Sciences, were selected using simple sampling method. Unstimulated saliva of the two groups was collected. Salivary total antioxidant capacity (TAC) and lipid peroxidation products were investigated and compared, using ferric reducing antioxidant power (FRAP) and thiobarbituric acid reactive substance (TBARS) methods, respectively. Data were analyzed using Student' t-test. Results. The mean and standard deviation of salivary TAC in patients with oral lichen planus (297.23 ± 149.72 μM) was significantly lower than that in the controls (791.43 ± 183.95 μM; P & 0.0001), and mean and standard deviation of salivary malondialdehyde (MDA) (0.49 ± 0.30 μM) was remarkably higher in oral lichen planus patients compared to the control group (0.15 ± 0.11 μM) (P & 0.0001). TAC was also reduced in both groups in line with an increase in the level of MDA (P & 0.0001, r = -0.48). Conclusion. The results of this study suggested that an increase in oxidative stress and an imbalance in antioxidant defense system in the saliva of oral lichen planus patients may be involved in the pathogenesis of oral lichen planus.

  17. Comparative study of cell alterations in oral lichen planus and epidermoid carcinoma of the mouth mucosa.

    Science.gov (United States)

    Sousa, Fernando Augusto Cervantes Garcia de; Paradella, Thaís Cachuté; Brandão, Adriana Aigotti Haberbeck; Rosa, Luiz Eduardo Blumer

    2009-01-01

    Currently, much is discussed regarding the pre-malignant nature of mouth mucosa lichen planus. The present study aims at analyzing the alterations found in the epithelial cells present in the oral cavity lichen planus, comparing them to those found in epidermoid carcinoma. Histological cross-sections of oral lichen planus and epidermoid carcinoma, dyed by hematoxylineosin, were analyzed through light microscopy. The most frequently found alterations in oral lichen planus were: an increase in the nucleus/cytoplasm relation (93.33%), nucleus membrane thickness (86.67%) and bi-nucleus or multinucleous (86.67%). The Student t test (alpha=5%) revealed a statistically significant difference between the average number of cell alterations in oral lichen planus (5.87+/-1.57) and in epidermoid carcinoma (7.60+/-1.81). As to the types of alterations, the chi-squared test also revealed statistically significant differences among the lesions assessed in relation to the following cell alterations: nuclear excess chromatism, atypical mitoses, cellular pleomorphism and abnormal cell differentiation (poral lichen planus, the results obtained in this study show that the alterations present in oral lichen planus differ considerably from those seen in epidermoid carcinoma, thus showing how distinct these two diseases are.

  18. NIR spectroscopy as a tool for discriminating between lichens exposed to air pollution.

    Science.gov (United States)

    Casale, Monica; Bagnasco, Lucia; Giordani, Paolo; Mariotti, Mauro Giorgio; Malaspina, Paola

    2015-09-01

    Lichens are used as biomonitors of air pollution because they are extremely sensitive to the presence of substances that alter atmospheric composition. Fifty-one thalli of two different varieties of Pseudevernia furfuracea (var. furfuracea and var. ceratea) were collected far from local sources of air pollution. Twenty-six of these thalli were then exposed to the air for one month in the industrial port of Genoa, which has high levels of environmental pollution. The possibility of using Near-infrared spectroscopy (NIRS) for generating a 'fingerprint' of lichens was investigated. Chemometric methods were successfully applied to discriminate between samples from polluted and non-polluted areas. In particular, Principal Component Analysis (PCA) was applied as a multivariate display method on the NIR spectra to visualise the data structure. This showed that the difference between samples of different varieties was not significant in comparison to the difference between samples exposed to different levels of environmental pollution. Then Linear Discriminant Analysis (LDA) was carried out to discriminate between lichens based on their exposure to pollutants. The distinction between control samples (not exposed) and samples exposed to the air in the industrial port of Genoa was evaluated. On average, 95.2% of samples were correctly classified, 93.0% of total internal prediction (5 cross-validation groups) and 100.0% of external prediction (on the test set) was achieved. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Potential of Lichen Compounds as Antidiabetic Agents with Antioxidative Properties: A Review

    Science.gov (United States)

    Karunaratne, Veranja

    2017-01-01

    The advancement in the knowledge of potent antioxidants has uncovered the way for greater insight in the treatment of diabetic complications. Lichens are a rich resource of novel bioactive compounds and their antioxidant potential is well documented. Herein we review the antidiabetic potential of lichens which have received considerable attention, in the recent past. We have correlated the antidiabetic and the antioxidant potential of lichen compounds. The study shows a good accordance between antioxidant and antidiabetic activity of lichens and points out the need to look into gathering the scarce and scattered data on biological activities for effective utilization. The review establishes that the lichen extracts, especially of Parmotrema sp. and Ramalina sp. have shown promising potential in both antidiabetic and antioxidant assays. Ubiquitous compounds, namely, zeorin, methylorsellinate, methyl-β-orcinol carboxylate, methyl haematommate, lecanoric acid, salazinic acid, sekikaic acid, usnic acid, gyrophoric acid, and lobaric acid have shown promising potential in both antidiabetic as well as antioxidant assays highlighting their potential for effective treatment of diabetic mellitus and its associated complications. The available compilation of this data provides the future perspectives and highlight the need for further studies of this potent herbal source to harvest more beneficial therapeutic antidiabetic drugs. PMID:28491237

  20. 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.)

  1. Lichen communities as climate indicators in the U.S. Pacific States.

    Science.gov (United States)

    Robert J. Smith; Sarah Jovan; Bruce. McCune

    2017-01-01

    Epiphytic lichens are bioindicators of climate, air quality, and other forest conditions and may reveal how forests will respond to global changes in the U.S. Pacific States of Alaska, Washington, Oregon, and California. We explored climate indication with lichen communities surveyed by using both the USDA Forest Service Forest Inventory and Analysis (FIA) and Alaska...

  2. Hepatitis C virus infections in oral lichen planus: a systematic review and meta-analysis.

    Science.gov (United States)

    Alaizari, N A; Al-Maweri, S A; Al-Shamiri, H M; Tarakji, B; Shugaa-Addin, B

    2016-09-01

    A role for hepatitis C virus in oral lichen planus has been postulated. This systematic review and meta-analysis of the existing epidemiological studies was conducted to determine if there is a correlation between oral lichen planus and hepatitis C virus infection. We examined the association between hepatitis C virus and oral lichen planus by conducting a systematic review and meta-analysis of case-control studies that examined the prevalence of anti-HCV antibodies in the serum of cases and controls. We searched PubMed, Embase and The Cochrane Library databases from 2005 to January 2015. Associations were measured using random-effect odds ratios (ORs) combined with 95% confidence intervals. Nineteen eligible studies, encompassing 1807 cases of OLP and 2519 controls, were retrieved and included in this review. The summary estimate OR for all studies was 6.07 (95% CI: 2.73-13.48), showing a statistically significant difference in the proportion of HCV seropositivity among oral lichen planus patients, compared with controls and substantial heterogeneity between studies (I(2) = 65%) as a result of a variety of geographical distributions. The association of hepatitis C virus infection with oral lichen planus emphasizes the importance of hepatitis C virus screening in oral lichen planus patients. © 2015 Australian Dental Association.

  3. [Oral medicine 9. Lichen planus and lichenoid lesions of the oral mucosa].

    Science.gov (United States)

    van der Meij, E H; Schepman, K P; de Visscher, J G A M

    2013-09-01

    The general dentist is sometimes confronted with white lesions of the oral mucosa. Oral lichen planus is the most common oral white lesion. The diagnosis can usually be made on the basis of the clinical aspect, but is sometimes made more difficult by certain abnormalities in the oral mucosa which clinically resemble oral lichen planus or by abnormalities which cannot be distinguished from oral lichen planus but have a different origin. Those lesions are classified as oral lichenoid lesions. Malignant deterioration has been described in allforms of oral lichen planus lesions and oral lichenoid lesions. There is no known method to predict or prevent malignant transformation. Nor are there any studies examining the efficacy of frequent follow-up visits. It seems sensible, in keeping with the tendency in recent literature, to schedule annual check-ups for patients to be on the safe side. These follow-up visits may reasonably be performed in a general dental practice.

  4. The measurement of serum TNF-α levels in patients with lichen planus.

    Science.gov (United States)

    Akpinar Kara, Yesim

    2017-12-01

    Lichen planus is a common mucocutaneous inflammatory skin disease with a multifactorial etiology. Cytokines play a key role in lichen planus pathogenesis. This study investigates the relationship between disease severity and levels of tumor necrosis factor-α (TNF-α), which is considered a primary cytokine that initiates cytotoxicity. Serum TNF-α levels were compared between a patient group (n = 34) and a control group (n = 20). TNF-α serum levels were measured using human TNF-α Enzyme-Linked Immunosorbent Assay (ELISA) test kits, and the two groups were statistically compared to each other. Mean serum TNF-α levels were found to be significantly higher in the patient group than in the control group (p 0.005). No relationship was detected between TNF-α levels and patients' sex. It is thought that TNF-α, a proinflammatory cytokine, may play an important role in the pathogenesis of lichen planus. TNF-α may be a simple and effective predictor to illustrate the inflammatory status in patients with lichen planus.

  5. 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.

  6. β-Orcinol Metabolites from the Lichen Hypotrachyna revoluta

    Directory of Open Access Journals (Sweden)

    Panagiota Papadopoulou

    2007-05-01

    Full Text Available Four new β-orcinol metabolites, hypotrachynic acid (1, deoxystictic acid (2, cryptostictinolide (3 and 8 ́-methylconstictic acid (4 along with the metabolites 8 ́-methylstictic acid (5, 8 ́-methylmenegazziaic acid (6, stictic acid (7, 8 ́-ethylstictic acid (8 and atranorin (9, that have been previously described, were isolated for the first time from the tissue extracts of the lichen Hypotrachyna revoluta (Flörke Hale. The structures of the new metabolites were elucidated on the basis of extensive spectroscopic analyses. Radical scavenging activity (RSA of the metabolites isolated in adequate amounts, was evaluated using luminol chemiluminescence and comparison with Trolox®.

  7. 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

  8. 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

  9. Association of Oral Lichen Planus with Chronic C Hepatitis. Review of the Data in Literature

    Science.gov (United States)

    GHEORGHE, Carmen; MIHAI, Lelia; PARLATESCU, Ioanina; TOVARU, Serban

    2014-01-01

    The relationship between chronic hepatitis C virus infection (HCV) and oral lichen planus (OLP) is a current topic in the field of oral medicine. Many studies of this association have been made over time. The geographic variation of the hepatitis C prevalence proved to be an important factor influencing the statistical results of the studies analyzing the association of the oral plan lichen with the hepatitis C virus. Approaching this issue is not to be neglected. Treatment outcomes in patients with oral lichen planus associated with chronic hepatitis C virus are often unsatisfactory compared to patients suffering from idiopathic oral lichen planus. Also, the evolution of oral lesions is often fluctuating, with repeated periods of relapse according to the degree of liver function decompensation. Background therapy for liver disease itself may influence lichen planus lesions. Thus, during therapy with interferon and ribavirin oral lesions may appear or become acute. PMID:25553136

  10. The natural depuration rate of 137Cs radionuclides in a lichen and moss species

    International Nuclear Information System (INIS)

    Topcuoglu, S.; Dawen, A.M. van; Gungor, N.

    1995-01-01

    Caesium-137 concentrations in lichen and moss samples have been studied for calculations of natural depuration rates. The lichen and moss species were collected from the same trees in western and eastern Black Sea region during the periods of 1987-1992 and 1990-1993, respectively. The natural depuration rates are estimated at biological half-lives. The pattern of depuration results represented by a single component for each non-vascular plant. The biological half-lives of 137 Cs in a lichen and moss samples (Xanthoria parietina and Leucodon immersus) are estimated to be 5.86 and 10.9 months, respectively. This work set supports the view that radioactivity monitoring in lichens can be a more useful monitor than mosses to determine the lasting effect of radioactive fallout. (author)

  11. Mapping of lichen frequencies as a tool in evaluating intensity of pollution

    Energy Technology Data Exchange (ETDEWEB)

    Kunze, M

    1972-01-01

    A method is presented for determining the intensity of air pollution by evaluating the frequency of lichen species growing on the trunks of trees. The lichens growing on the trunks of isolated trees in the surroundings of factories or other pollutants have been investigated. A ladder enclosing the panels is used to determine the frequency: the calculation is made electronically and permits statistical statements about the quantity of the lichens to be made. The numerical material evaluated consists of reproduceable data obtained by a standardized method that appears to be suitable for routine use. Pollution zones can be recognized by changes in frequency of the various sensitive species.

  12. Monitoring air quality with lichens: A comparison between mapping in forest sites and in open areas

    International Nuclear Information System (INIS)

    Policnik, Helena; Simoncic, Primoz; Batic, Franc

    2008-01-01

    Four different methods of epiphytic lichen mapping were used for the assessment of air quality in the region under the influence of the Sostanj Thermal Power Plant (Salek Valley, Slovenia). Three methods were based on the presence of different lichen species (VDI, EU and ICP-Forest), the fourth on a frequency and coverage assessment of different growth forms of epiphytic lichens, e.g. crustose, foliose and fruticose (SI). A comparison of the results from the assessment of air quality between forest sites (ICP-Forest, SI) and open areas (VDI, EU and SI), obtained by the different methods of epiphytic lichen mapping, is presented in the contribution. Data showed that lichen species richness is worse in forest sites in comparison with open areas. From the data obtained it can be concluded that epiphytic lichen mapping in open areas is a better method for the assessment of air pollution in a given area than mapping in forest sites. The species-based methods in open areas are more powerful and useful for air quality assessment in polluted research areas than the SI and ICP-Forest methods. - The mapping of epiphytic lichens in open areas is more suitable for air quality assessment than mapping in forest sites in the Salek Valley, Slovenia

  13. Epiphytic lichen diversity in central European oak forests: Assessment of the effects of natural environmental factors and human influences

    International Nuclear Information System (INIS)

    Svoboda, David; Peksa, Ondrej; Vesela, Jana

    2010-01-01

    We investigated lichen diversity in temperate oak forests using standardized protocols. Forty-eight sites were sampled in the Czech Republic, Slovakia and Hungary. The effects of natural environmental predictors and human influences on lichen diversity (lichen diversity value, species richness) were analysed by means of correlation tests. We found that lichen diversity responded differently to environmental predictors between two regions with different human impact. In the industrial region, air pollution was the strongest factor. In the agricultural to highly forested regions, lichen diversity was strongly influenced by forest age and forest fragmentation. We found that several natural factors can in some cases obscure the effect of human influences. Thus, factors of naturality gradient must be considered (both statistically and interpretively) when studying human impact on lichen diversity. - We detected the different responses of lichens to ecological predictors in polluted and unpolluted areas.

  14. Natural radionuclides and 137Cs in moss and lichen in eastern Serbia

    Directory of Open Access Journals (Sweden)

    Čučulović Ana

    2012-01-01

    Full Text Available The paper presents the results of radionuclides determination in moss (Homolothecium sp., Hypnum Cupressiforme sp., and Brachythecium sp. and lichen (Cladonia sp. sampled in the region of Eastern Serbia during 1996-2010. The activities in moss are in the range of 100-500 Bq/kg d. w. for 40K, and 5-50 Bq/kg d. w. for 226Ra and 232Th, while the “soil-to-moss” transfer factors are 0.45 for 40K, 3 for 226Ra, and 0.3 for 232Th. The spatial distribution of the 137Cs activities is highly non-uniform; some values reach 500 Bq/kg d. w., with less than 10% of the samples, mainly the ones taken prior to 2000, with the activity above 1000 Bq/kg d. w. The variations in the content of natural radionuclides among the moss species are not significant. The frequency pattern of the activities of natural radionuclides in lichen is similar to the one in moss, but the activities in lichen are to some extent lower. The mean activity of 137Cs in lichen is below 400 Bq/kg d. w. The mean activities of 7Be in moss and lichen sampled in 2006 and 2008 are in the range of 41-122 Bq/kg d. w., with pronounced variations between the sampling sites.

  15. Role of Mast Cells in Oral Lichen Planus and Oral Lichenoid Reactions.

    Science.gov (United States)

    Ramalingam, Suganya; Malathi, Narasimhan; Thamizhchelvan, Harikrishnan; Sangeetha, Narasimhan; Rajan, Sharada T

    2018-01-01

    Oral lichen planus (OLP) is a chronic T cell mediated disease of oral mucosa, skin, and its appendages with a prevalence of 0.5 to 2.6% worldwide. Oral lichenoid reactions (OLR) are a group of lesions with diverse aetiologies but have clinical and histological features similar to OLP, thereby posing a great challenge in differentiating both lesions. Mast cells are multifunctional immune cells that play a major role in the pathogenesis of lichen planus by release of certain chemical mediators. Increased mast cell densities with significant percentage of degranulation have been observed as a consistent finding in pathogenesis of oral lichen planus. The current study was aimed at quantifying the mast cells in histopathological sections of OLP and OLR thereby aiding a means of distinguishing these lesions. The study group involved 21 cases of oral lichen planus, 21 cases of oral lichenoid reactions, and 10 control specimens of normal buccal mucosa. All the cases were stained with Toluidine Blue and routine haematoxylin and eosin and the mast cells were quantified. The results were analyzed using the Kruskal-Wallis test and an intergroup analysis was performed using Mann-Whitney U test. The number of mast cells showed an increased value in oral lichen planus when compared to oral lichenoid reaction and thus an estimation of mast cells count could aid in distinguishing OLP from OLR histopathologically.

  16. Genome-Wide Association Study Identifies Risk Variants for Lichen Planus in Patients With Hepatitis C Virus Infection.

    Science.gov (United States)

    Nagao, Yumiko; Nishida, Nao; Toyo-Oka, Licht; Kawaguchi, Atsushi; Amoroso, Antonio; Carrozzo, Marco; Sata, Michio; Mizokami, Masashi; Tokunaga, Katsushi; Tanaka, Yasuhito

    2017-06-01

    There is a close relationship between hepatitis C virus (HCV) infection and lichen planus, a chronic inflammatory mucocutaneous disease. We performed a genome-wide association study (GWAS) to identify genetic variants associated with HCV-related lichen planus. We conducted a GWAS of 261 patients with HCV infection treated at a tertiary medical center in Japan from October 2007 through January 2013; a total of 71 had lichen planus and 190 had normal oral mucosa. We validated our findings in a GWAS of 38 patients with HCV-associated lichen planus and 7 HCV-infected patients with normal oral mucosa treated at a medical center in Italy. Single-nucleotide polymorphisms in NRP2 (rs884000) and IGFBP4 (rs538399) were associated with risk of HCV-associated lichen planus (P lichen planus. The odds ratios for the minor alleles of rs884000, rs538399, and rs9461799 were 3.25 (95% confidence interval, 1.95-5.41), 0.40 (95% confidence interval, 0.25-0.63), and 2.15 (95% confidence interval, 1.41-3.28), respectively. In a GWAS of Japanese patients with HCV infection, we replicated associations between previously reported polymorphisms in HLA class II genes and risk for lichen planus. We also identified single-nucleotide polymorphisms in NRP2 and IGFBP4 loci that increase and reduce risk of lichen planus, respectively. These genetic variants might be used to identify patients with HCV infection who are at risk for lichen planus. Copyright © 2017 AGA Institute. Published by Elsevier Inc. All rights reserved.

  17. Response of exposed bark and exposed lichen to an urban area

    Energy Technology Data Exchange (ETDEWEB)

    Cruz, A.M.J. [Polytechnic Institute of Coimbra, Oliveira do Hospital (Portugal). Oliveira do Hospital College of Technology and Management; Freitas, M.C.; Canha, N. [URSN, Sacavem (Portugal). Inst. Tecnologico e Nuclear (ITN); Verburg, T.G.; Wolterbeek, H.T. [Technical Univ. of Delft (Netherlands). Dept. of Radiation, Radionuclides and Reactors

    2011-07-01

    The aim of this study is to understand emission sources of chemical elements using biomonitoring as a tool. The selected lichen and bark were respectively Parmotrema bangii and Criptomeria japonica, sampled in the pollution-free atmosphere of Azores (Sao Miguel island), Portugal, and were exposed in the courtyards of 22 basic schools of Lisbon. The exposure was from January to May 2008 and from June to October 2008 (designated through the text as winter and summer respectively). The chemical element concentrations were determined by INAA. Conductivity of the lichen samples was measured. Factor analysis (MCTTFA) was applied to winter/summer bark/lichen exposed datasets. Arsenic emission sources, soil with anthropogenic contamination, a Se source, traffic, industry, and a sea contribution, were identified. In lichens, a physiological source based on the conductivity values was found. The spatial study showed contribution of sources to specific school positioning. Conductivity values were high in summer in locations as international Lisbon airport and downtown. Lisbon is spatially influenced by marine air mass transportation. It is concluded that one air sampler in Lisbon might be enough to define the emission sources under which they are influenced. (orig.)

  18. How general dentists could manage a patient with oral lichen planus

    Science.gov (United States)

    Robledo-Sierra, Jairo

    2018-01-01

    Background The literature hardly contains information on how patients suffering from oral lichen planus could be managed by dentists. Material and Methods Based on the limited available literature and particularly on the long-term clinical and histopathological experience of one of the authors, suggestions on how dentists could manage patients with oral lichen planus have been put forward. Results: In most cases, the dentist should be able to establish a correct diagnosis. Results In most cases, the dentist should be able to establish a correct diagnosis. Occasionally, the dentist may call upon a specialist, usually an oral medicine specialist or an oral and maxillofacial surgeon for confirmation of the diagnosis, possibly a biopsy procedure, and management of the patient in case of severe symptoms. Proper patient information is of utmost importance in the management. Conclusions General dentists can be expected to manage the majority of patients with oral lichen planus. Some patients may need to be referred for diagnostic purposes to a specialist; this is also the case for the rare patient with severe symptoms, possibly requiring systemic treatment. Key words:Oral mucosal disease, oral lichen planus. PMID:29476684

  19. Preliminary analysis of a new IAEA lichen AQCS material

    International Nuclear Information System (INIS)

    Grass, F.; Bichler, M.; Dorner, J.; Ismail, S.; Kregshammer, P.; Zamini, S.; Gwozdz, R.

    2000-01-01

    Lichen with a higher content on interesting trace elements were analyzed by activation analysis and by X-RF measurements on pressed lichen samples. The activation analyses were performed in three different ways: Short-time AA in the Fast Irradiation and Measurement System. Up to 580mg of lichen were irradiated 5-300s in polyethylene containers. Single spectra and spectra of 6 samples were summed up and evaluated. Longer irradiation at the ASTRA-Reactor: 2h at 8E13/s cm 2 . 100-150mg of lichen were irradiated in quartz suprasil vials. Longer irradiation at the Institute's TRIGA-Reactor: 6-7h at 1.8E12/s cm 2 , sample size: 7-48g of lichen were irradiated in polyethylene containers and after irradiation transferred to new measurement containers and measured in a device constructed by Gwozdz. The X-RF analysis was performed with a Spectrace 5000 energy dispersive X-ray fluorescence analyzer with a rhodium anode tube for excitation. From the activation analyses, the following elements were determined: Ag, Al, As, Au, Ba, Br, Ca, Cd, Ce, Cl, Co, Cr, Cs, Cu, Dy, Eu, Fe, Hf, Hg, I, K, La, Lu, Mg, Mn, Mo, Na, Nd, Ni, Rb, Sb, Sc, Se, Sr, Ta, Tb, Th, Ti, U, V, Yb, Zn. From the X-RF measurements, the elements Ag, Al, Ba, Br, Ca, Cd, Cu, Fe, I, K, Mg, Mn, P, Pb, Rb, S, Sb, Si, Sn, Sr, Ti, Y, Zn, and Zr were evaluated. From the X-RF data as well as from the AA-data of samples of different weight it is apparent that milling to a particle size of 200m is not sufficient for all elements, especially not for gold, cadmium, and cobalt which may be present as nuggets or accessory heavy minerals. It is therefore advisable to mill the sample to a particle size which is an order of magnitude smaller and remove the not adhering dust, even if this lowers the content of these elements. (author)

  20. Characterization of Microsatellite Loci in Lichen-Forming Fungi of Bryoria Section Implexae (Parmeliaceae

    Directory of Open Access Journals (Sweden)

    Olga Nadyeina

    2014-07-01

    Full Text Available Premise of the study: The locally rare, haploid, lichen-forming fungi Bryoria capillaris, B. fuscescens, and B. implexa are associated with boreal forests and belong to Bryoria sect. Implexae. Recent phylogenetic studies consider them to be conspecific. Microsatellite loci were developed to study population structure in Bryoria sect. Implexae and its response to ecosystem disturbances. Methods and Results: We developed 18 polymorphic microsatellite markers using 454 pyrosequencing data assessed in 82 individuals. The number of alleles per locus ranged from two to 13 with an average of 4.6. Nei's unbiased gene diversity, averaged over loci, ranged from 0.38 to 0.52. The markers amplified with all three species, except for markers Bi05, Bi15, and Bi18. Conclusions: The new markers will allow the study of population subdivision, levels of gene introgression, and levels of clonal spread of Bryoria sect. Implexae. They will also facilitate an understanding of the effects of forest disturbance on genetic diversity of these lichen species.

  1. Successful treatment of bullous lichen planus with acitretin monotherapy. Review of treatment options for bullous lichen planus and case report.

    Science.gov (United States)

    Rallis, Efstathios; Liakopoulou, Angeliki; Christodoulopoulos, Constantinos; Katoulis, Alexandros

    2016-12-31

    Bullous lichen planus (BLP) is a rare variant of lichen planus, characterized by the development of vesicular and bullous lesions, of skin, nails, hair and/or mucosa. We present a case of 63-year-old woman with BLP, unresponsive to previous therapies with topical corticosteroids, topical calcipotriol, antihistamines and oral cyclosporine (4 mg/kg/day for 4 months). She was already receiving treatment for arterial hypertension, hyperlipidemia, atrial fibrillation and uncontrolled diabetes mellitus. Acitretin was administered for 5 months with complete remission of BLP lesions and no major side effects. This is probably the first reported case of BLP treated with acitretin monotherapy. In this case acitretin was an efficacious and well-tolerated therapeutic option for BLP.

  2. 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 ...

  3. 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)

  4. Characterization and speciation of mercury in mosses and lichens from the high-altitude Tibetan Plateau.

    Science.gov (United States)

    Shao, Jun-Juan; Liu, Cheng-Bin; Zhang, Qing-Hua; Fu, Jian-Jie; Yang, Rui-Qiang; Shi, Jian-Bo; Cai, Yong; Jiang, Gui-Bin

    2017-06-01

    The accumulation and species of mercury (Hg) in mosses and lichens collected from high-altitude Tibetan Plateau were studied. The altitudes of the sampling sites spanned from 1983 to 5147 m, and a total of 130 mosses and 52 lichens were analyzed. The total mercury (THg) contents in mosses and lichens were in the ranges of 13.1-273.0 and 20.2-345.9 ng/g, respectively. The average ratios of methylmercury (MeHg) in THg in mosses and lichens were 2.4 % (0.3-11.1 %) and 2.7 % (0.4-9.6 %), respectively, which were higher than those values reported in other regions. The contents of THg in both mosses and lichens were not correlated with the THg in soils (p > 0.05). The lipid contents displayed a significantly positive correlation with concentrations of MeHg in mosses (r = 0.461, p Tibetan Plateau.

  5. 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

  6. 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

  7. Mycophenolate mofetil in erosive genital lichen planus: a case and review of the literature.

    Science.gov (United States)

    Deen, Kristyn; McMeniman, Erin

    2015-03-01

    Erosive genital lichen planus is a disabling, inflammatory mucocutaneous condition that can cause significant patient morbidity and loss of function. Treatment initially involves topical corticosteroids but some patients can have severe treatment-resistant courses requiring systemic immunosuppression. With potentially unfavorable adverse effect profiles and subsequent intolerance of these agents by patients, erosive lichen planus can ultimately be a challenging condition to treat effectively. We present a case of a 66-year-old woman with treatment-resistant erosive genital lichen planus who was successfully managed with mycophenolate mofetil. Although there is only weak evidence for this agent in this condition, its role in dermatology is growing due to its efficacy and advantageous adverse effect profile and should therefore be considered in patients with treatment-resistant erosive genital lichen planus. © 2015 Japanese Dermatological Association.

  8. What influences heavy metals accumulation in arctic lichen Cetrariella delisei in Svalbard?

    Science.gov (United States)

    Węgrzyn, Michał; Wietrzyk, Paulina; Lisowska, Maja; Klimek, Beata; Nicia, Paweł

    2016-12-01

    The main aim of this study was to identify variations in heavy metal concentrations in Cetrariella delisei along a transect from a High Arctic glacier forehead to the shoreline as well as determine the main environmental factors influencing the deposition of heavy metals in arctic lichens. The macrolichen Cetrariella delisei appears to be an interesting alternative to those lichen species used in the past (e.g. Flavocetraria nivalis, Cladonia sp.) for heavy metal biomonitoring purposes in the Arctic: it is widely distributed, easy to identify and reluctantly grazed by reindeer. Fieldwork was conducted in the summer of 2012 in the Kaffiøyra Plain, Oskar II Land, NW Spitsbergen. C. delisei and soil samples were collected from 5 localities. Concentrations of Cr, Mn, Ni, Cu, Zn, Pb, and Cd were measured in each sample. A bioaccumulation factor (BAF) was calculated for all the analyzed elements. The BAFs for Cu, Mn, and Ni showed a relatively low accumulation level in lichen thalli. On the other hand, the BAFs for Cr, Pb, and Zn, revealed an increased accumulation level in C. delisei. The Cd content in lichen is almost equal to its level in the soil. The statistical analyses covered three environmental factors: soil pH, substrate type and distance from the shoreline. The data were examined using the Kruskal-Wallis test, canonical correspondence analysis and a permutation test. The results show that distance from the shoreline had the greatest influence on the majority of the heavy metal concentrations in the lichen thalli and the soil. However, the level of Mn accumulated in the soil is determined by its source in the glacier. Moreover, the soil pH had the greatest effect on the Cd accumulated in the soil and the Mn accumulated in the lichen thalli.

  9. Determination of trace elements in lichen samples by instrumental neutron activation analysis

    International Nuclear Information System (INIS)

    Saiki, Mitiko; Horimoto, Lidia K.; Vasconcellos, Marina B.A.; Marcelli, Marcelo P.; Sumita, Nairo M.; Saldiva, Paulo H.N.

    2001-01-01

    Samples of Canoparmelia texana lichen collected in different sites of Sao Paulo and Parana States, Brazil, were analysed by neutron activation analysis in order to obtain preliminary information on the air quality in these regions and also to select a region of interest for biomonitoring studies. Also Tadescantia pallida plant has been analysed in order to study the viability of using this specimen in environmental pollution monitoring. Lichens samples were collected from tree barks which were also collected to investigate the contribution of substrate derived elements to elements present in lichens. Young and old leaves of T. pallida were collected separately in order to study the leaf age effects on their elemental levels. The samples were cleaned, washed with distilled water, dried and ground for the analyses. Samples and standards were irradiated at the IEA-Rlm nuclear reactor for short and long periods and concentrations of the elements Al, As, Ca, Cd, Cl, Co, Cr, Cs, Fe, Hf, Mg, Mn, Rb, Sb, Sc, D, Th, U, V Zn and lanthanides were determined. Preliminary results obtained for T. texana lichen indicated that three sites (Ibiuna, Botanical Garden and Parque de Vila Velha) present low concentrations of the most elements analysed. Therefore lichens from these regions could be analysed to establish baseline levels of elements for monitoring purposes. Samples collected in open areas presented high concentrations of some elements probably due to the accumulation of elements originating from soil and from heavy vehicular traffic. Elemental concentrations obtained in outer barks were similar or smaller than those results obtained for lichens. Results obtained for T. pallida indicated that concentrations of elements in old leaves of this plant are of the same magnitude or slightly higher than those presented in young ones. (author)

  10. Lichen elements as pollution indicators: evaluation of methods for large monitoring programmes

    Science.gov (United States)

    Susan Will-Wolf; Sarah Jovan; Michael C. Amacher

    2017-01-01

    Lichen element content is a reliable indicator for relative air pollution load in research and monitoring programmes requiring both efficiency and representation of many sites. We tested the value of costly rigorous field and handling protocols for sample element analysis using five lichen species. No relaxation of rigour was supported; four relaxed protocols generated...

  11. High prevalence of esophageal involvement in lichen planus: a study using magnification chromoendoscopy

    NARCIS (Netherlands)

    Quispel, R.; van Boxel, O. S.; Schipper, M. E.; Sigurdsson, V.; Canninga-van Dijk, M. R.; Kerckhoffs, A.; Smout, A. J.; Samsom, M.; Schwartz, M. P.

    2009-01-01

    BACKGROUND AND STUDY AIMS: The first cases of squamous cell carcinoma in esophageal lichen planus were recently described. We performed a study to establish the prevalence of endoscopic and histopathologic abnormalities consistent with lichen planus and (pre-) malignancy in a cohort of patients with

  12. 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

  13. Characterization of Microsatellite Loci in the Himalayan Lichen Fungus Lobaria pindarensis (Lobariaceae

    Directory of Open Access Journals (Sweden)

    Shiva Devkota

    2014-04-01

    Full Text Available Premise of the study: Microsatellite loci were developed for the rare, Himalayan, endemic haploid lichen fungus, Lobaria pindarensis, to study its population subdivision and the species' response to forest disturbance and fragmentation. Methods and Results: We developed 18 polymorphic microsatellite markers using 454 pyrosequencing data and assessed them in 109 individuals. The number of alleles per locus ranged from three to 11 with an average of 6.9. Nei's unbiased gene diversity, averaged over loci, ranged from 0.514 to 0.685 in the three populations studied. The cross-amplification success with related species (L. chinensis, L. gyrophorica, L. isidiophora, L. orientalis, L. pulmonaria, L. spathulata, and Lobaria sp. was generally high and decreased with decreasing relationship to L. pindarensis. Conclusions: The new markers will allow the study of genetic diversity and differentiation within L. pindarensis across its distribution. Moreover, they will enable us to study the effects of forest management on the genetic population structure of this tree-colonizing lichen and to carry out population genetic studies of related species in East Asia.

  14. 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.

  15. Use of bioindicators to evaluate air quality and genotoxic compounds in an urban environment in Southern Brazil

    International Nuclear Information System (INIS)

    Käffer, Márcia Isabel; Lemos, Andréa T.; Apel, Miriam Anders; Rocha, Jocelita Vaz; Martins, Suzana Maria de Azevedo

    2012-01-01

    Biological indicators are widely used to monitor genotic compounds and air quality in urban environments. Parmotrema tinctorum and Teloschistes exilis have been used to verify the presence of pollutants and analyze morphophysiological alterations in the thallus of species caused by their action. Species were exposed for seven months, in an urban area, in southern Brazil. Mutagenicity and cytotoxicity of PM10 organic extracts were assessed in the Salmonella/microsome assay at two stations. High concentrations of S, Pb, Cr, Zn and Hg were registered in the last period of exposure and more significant morphophysiological damages were verified in the lichens. Generally a higher mutagenic activity is observed in organic extracts of airborne particulate matter during the first months and in the third period of exposure of lichens. In addition, nitro compounds was detected through nitro-sensitive strains. Lichens and mutagenic biomarkers enabled the evaluation of air quality and the presence of environmentally-aggressive compounds. - Highlights: ► Biological indicators are widely used to monitor genotic compounds and air quality in urban environments. ► High concentrations of S and metals were registered in the last period of exposure. ► More significant morphophysiological damages were verified in the lichens in the last period of exposure. ► The results reveals that a set of factors contributed to the morphophysiological alterations of lichens. - Bioindicators are valuable monitors of genotoxic compounds and atmospheric pollution.

  16. Chemical Composition, Antioxidant, and Antimicrobial Activities of Lichen Umbilicaria cylindrica (L. Delise (Umbilicariaceae

    Directory of Open Access Journals (Sweden)

    Nedeljko T. Manojlovic

    2012-01-01

    Full Text Available The phytochemical analysis of methanol and chloroform extracts of Umbilicaria cylindrica was determined by HPLC-UV method. The predominant phenolic compound in both extracts was depsidone, salazinic acid (1. Besides salazinic acid, the tested extracts of U. cylindrica contain norstictic acid (2, methyl-β-orcinol carboxylate (3, ethyl haematommate (4, atranorin (5, and usnic acid (6, in different amounts and relations. The lichen extracts showed comparable and strong antioxidant activity, exhibited higher DPPH and hydroxyl radical scavengings, chelating activity, and inhibitory activity towards lipid peroxidation. The lichen extracts demonstrated important antimicrobial activity against eight strains with MIC values from 15.62 to 62.50 μg/mL. This is the first report of the detail chemical composition and antioxidant activity of the lichen Umbilicaria cylindrica, and the results suggest that this lichen can be used as a new source of the natural antioxidants and the substances with antimicrobial features.

  17. Se Concentrations in Epiphytic Lichens From the Boreal Forest of Forthern Québec

    Science.gov (United States)

    Marin, L.; Lhomme, J.; Carignan, J.

    2004-05-01

    The knowledge of Se concentration in environmental samples is important because this element may be both toxic and nutrient for live organisms. This study aims to characterise the Se concentration in lichen samples in order to document the variability of atmospheric fallout. Lichens are of particular interest because their epiphytic character makes them totally dependant of atmospheric nutrients, so that their chemical composition reflects that of atmospheric matter. Lichens hanging on tree branches were sampled in various location of the boreal forest of northern Québec. We developed a separation and pre-concentration technique for Se analysis of low mineral matrix samples by GFAAS. After mineralisation and addition of a Se-free mineral charge to the sample, total Se is reduced to Se IV and fixed onto a thiol cotton. The latter is dissolved and directly analysed by GFAAS. A limit of determination of 0.02 ppm in the solid sample and a precision (relative standard deviation) varying from 3 to 15% was found through the course of this study. Our results are very similar to the certified values of the reference materials analysed, suggesting a good accuracy of the method for organic materials. Some lichen samples were also analysed by INAA and the agreement between results obtained by both techniques is not always perfect. There is, however, no systematic bias between the methods. Some samples agree within analytical uncertainty (about 5%), whereas others differ by more than 20%. The most probable reason why such discrepancies are observed is because these lichen samples were not crushed and homogenised before analysis. Indeed, some duplicate samples analysed by INAA yielded results that differed by more than 20%, while other agreed within 2%. Considering these facts, the overall agreement between GFAAS and INAA is pretty much satisfactory. The Se concentrations measured in lichens vary from 1.2 to 0.3 ppm and decrease from the coast of Hudson Bay towards inland at

  18. Elemental analysis of lichen bioaccumulators before exposure as transplants in air pollution monitoring

    International Nuclear Information System (INIS)

    Pantelica, A.; Cercasov, V.

    2003-01-01

    Lichen transplants from relatively unpolluted sites are successfully used as heavy metal bioaccumulators for long-term air pollution monitoring. Significant element accumulations are generally revealed after 6 to 12 months of exposure. The main objective of this interdisciplinary research is to get a low-price survey of the air pollution level in some critical areas of Romania by nuclear and atomic analytical methods, based on the element accumulating property of transplanted lichens. The lichen species Evernia prunastri and Pseudevernia furfuracea collected from the Prealps, northeast Italy, have been selected for this study. Experimental setup for standardized lichen exposure needs special plastic frames ('little traps': 15 · 15 · 1.5 cm, with 1cm 2 mesh) which are fixed horizontally on stainless steel posts at about 1.5 m above the ground. Prior to exposure, the lichen material is cleansed of some vegetal impurities and then shortly washed using de-ionised water. The initial (zero-level) contents of lichens were determined by Instrumental Neutron Activation Analysis (INAA) and Energy Dispersive X-Ray Fluorescence Analysis (EDXRFA) methods. INAA was carried out at the Institute of Physics and Nuclear Engineering in Bucharest (IFIN) and while EDXRFA at the University of Hohenheim in Stuttgart. The investigated elements were: As, Br, Ca, Cd, Co, Cr, Cu, Fe, K, Mn, Ni, Pb, S, Sb, Se, V and Zn. From among them, Cd, Co and Sb can be determined only by INAA and ICP-MS, Pb only by EDXRFA and PIXE, and S only by EDXRFA. A statistical intercomparison of the results allowed a good quality control of the used analytical methods for these specific matrices. This work was supported in part by European Commission Center of Excellence Project ICA1-CT-2000-70023: IDRANAP (Inter-Disciplinary Research and Applications based on Nuclear and Atomic Physics), Work Package 2 (Air pollution monitoring by sampling airborne particulate matter combined with lichen bioaccumulator exposure

  19. Evaluation of the serum zinc level in erosive and non-erosive oral lichen planus.

    Science.gov (United States)

    Gholizadeh, N; Mehdipour, M; Najafi, Sh; Bahramian, A; Garjani, Sh; Khoeini Poorfar, H

    2014-06-01

    Lichen planus is a chronic inflammatory immunologic-based disease involving skin and mucosa. This disease is generally divided into two categories: erosive and non-erosive. Many etiologic factors are deliberated regarding the disease; however, the disorders of immune system and the role of cytotoxic T-lymphocytes and monocytes are more highlighted. Zinc is an imperative element for the growth of epithelium and its deficiency induces the cytotoxic activity of T-helper2 cells, which seems to be associated with lichen planus. This study was aimed to evaluate the levels of serum zinc in erosive and non-erosive oral lichen planus (OLP) and to compare it with the healthy control group to find out any feasible inference. A total of 22 patients with erosive oral lichen planus, 22 patients with non erosive OLP and 44 healthy individuals as the control group were recruited in this descriptive-comparative study. All the participants were selected from the referees to the department of oral medicine, school of dentistry, Tabriz University of Medical Sciences. Serum zinc level was examined for all the individuals with liquid-stat kit (Beckman Instruments Inc.; Carlsbad, CA). Data were analyzed by adopting the ANOVA and Tukey tests, using SPSS 16 statistical software. The mean age of patients with erosive and non-erosive LP was 41.7 and 41.3 years, respectively. The mean age of the healthy control group was 34.4 years .The mean serum zinc levels in the erosive and non erosive lichen planus groups and control groups were 8.3 (1.15), 11.15 (0.92) and 15.74 (1.75) μg/dl respectively. The difference was statistically significant (poral lichen planus. This finding may probably indicate the promising role of zinc in development of oral lichen planus.

  20. HPLC-MS Analysis of Lichen-Derived Metabolites in the Life Stages of Crambidia cephalica (Grote & Robinson).

    Science.gov (United States)

    Anderson, Timothy J; Wagner, David L; Cooper, Bruce R; McCarty, Megan E; Zaspel, Jennifer M

    2017-01-01

    Tiger moths (Lepidoptera: Erebidae: Arctiinae: Arctiini) are notable for their specialized associations with hosts that produce toxic secondary compounds, and are thus an ideal study system for understanding insect-plant interactions and the evolution of antipredatory defense. Likewise, their sister lineage (Arctiinae: Lithosiini) has been documented feeding on algae and lichens, and is known to sequester lichen-derived secondary compounds from the larval to adult stages. Prevalence of lichenivory in this early radiation (ca. 3000 species) may provide clues to the phylogenetic basis for storied chemical sequestration within all tiger moths. Despite the evolutionary significance of this trait, we lack a basic understanding of the extent of lichenivory among lithosiines, and the distribution of sequestered chemicals among life stages. The dynamics of chemical sequestration throughout the lifecycle for the lichen moth Crambidia cephalica were investigated by testing the hypothesis that lichen-derived metabolites are unequally distributed among life stages, and that laboratory-reared C. cephalica have less metabolite diversity than wild-caught individuals. Crambidia cephalica was reared on Physcia, and analyzed using high-performance liquid chromatography coupled to mass spectrometry (HPLC-MS). Several putative lichen-derived metabolites were detected across three life stages, i.e., larval, pupal, and adult, and differences among life stages and lichen host were observed. These results provide evidence that multiple lichen-derived metabolites are sequestered by C. cephalica; some metabolites are retained through adulthood, and others are lost or modified in earlier life stages. The presence of differing lichen-derived metabolites across life stages may indicate functional properties of the metabolites for C. cephalica with regards to chemical protection from antagonists, and other physiological processes.