Rapid photosynthetic recovery of a snow-covered feather moss and Peltigera lichen during sub-Arctic midwinter warming

Background: Arctic lichens and mosses are covered by snow for more than half the year and are generally considered as being dormant for most of this period. However, enhanced frequency of winter warming events due to climate change can cause increased disturbance of their protective subnivean environment.

Aim: To further understand cryptogamic responses to midwinter warming we compared the ecophysiological performance of one lichen and one moss species during a simulated warming event.

Methods: We measured photosynthesis and dark respiration in samples of the moss Hylocomium splendens and the lichen Peltigera aphthosa removed from under snow, and on natural refreezing after the warming event, which was simulated by using infrared heaters suspended above the ground.

Results: The moss exposed to light at +5 °C immediately after removal from their subnivean environment and from warmed plots showed positive net gas exchange within 332 s; the lichen required 1238 s. Photosynthesis and nitrogen fixation rates were equal to that, or higher than, during the preceding growing season. Upon refreezing after the event, moss photosynthesis declined considerably.

Conclusions: The moss, and to a lesser extent the lichen, may contribute to subnivean midwinter ecosystem respiration, and both are opportunistic, and can take advantage of warmer winter phases for photosynthesis and growth. This ought to be taken into account in vegetation change projections of cryptogam-rich ecosystems.     

Fourteenth research symposium University of Durham 1974

Abstract

Background: Few studies analysing lichen diversity have simultaneously considered interactions among drivers that operate at different spatial and temporal scales.

Aims: The aims of this study were to evaluate the relative importance of host tree, and local, landscape and historical factors in explaining lichen diversity in managed temperate forests, and to test the potential interactions among factors acting at different spatial scales.

Methods: Thirty-five stands were selected in the ?rség region of western Hungary. Linear models and multi-model inference within an information-theory framework were used to evaluate the role of different variables on lichen species richness.

Results: Drivers at multiple spatial scales contributed to shaping lichen species richness both at the tree and plot levels. Tree-level species richness was related to both tree- and plot-level factors. With increasing relative diffuse light lichen species richness increased; this effect was stronger on the higher than on the lower part of the trunks. At the plot scale, species richness was affected by local drivers. Landscape and historical factors had no, or only a marginal, effect.

Conclusions: Lichen conservation in temperate managed forests could be improved if the complex interactions among host tree quality and availability, micro-climatic conditions, and management were taken into consideration.     

我院远程医疗会诊情况分析与思考

目的 总结和回顾多年来远程会诊工作开展情况,探索提高远程医疗效率的方法。方法 对完成的139例远程会诊的相关资料统计分析。结果 目前远程会诊主要承担的是偏远地区、不方便外出就诊的患者,近90%是为病情急危患者组织的急诊会诊,60%是常见病、多发病中的复杂难治病例。结论 提高远程会诊质量和效率,有利于节约医疗资源,使更多基层患者得到救治,开展远程疑难病例、死亡病例讨论及远程查房等方式,开辟远程会诊的新领域。     

Licheni Nuovi O Interessanti Delle Coste Italiane

Abstract

New or interesting Lichens of italian coasts. — The autor describes a lichen new to Italy, Acarospora microcarpa (Nyl) Wedd, a mediterranean species, found in southern France only hitherto. The lichen was gathered on the tufs rocks of the Isle of Procida; so the species is classed among the cryptogamic flora of phlegrean tufs.

The presence of Acarospora trachytica Jatta on the isle of Procida is therefore indicated, a species that is somewhat rare and known so far only on the Island of Ischia and Vesuvius.

Some new places for the marine lichen, Verrucaria symbalana Nyl. are reported, and the particular ecological interest of the species and its full geographical placement considered.

Finally, new places for Lichina confinis Ag., in Italy are given. This is a marine species of considerable ecological interest.     

Edge effects on epiphytic lichen diversity in the forest-steppe of the Kazakh Altai

Background: Forests in forest-steppe ecotones are usually highly fragmented and much of the forested area is exposed to climate and land-use-related edge effects.

Aim: To test the hypothesis that the epiphytic lichen diversity at the forest edges was reduced compared with that in the forest interior, and to analyse lichen diversity in comparison with the more highly elevated and more continental Mongolian Altai.

Methods: Six plots each in the interior and the edge with a total of 240 Larix sibirica trees were studied in the Katon-Karagai National Park, East Kazakhstan.

Results: Species richness and evenness at the tree level were higher in the interior than at the edge. The epiphytic lichen diversity in the forest interior was similar in the Kazakh and Mongolian Altai, whereas that at the forest edge was lower in the Mongolian Altai.

Conclusions: Strong degradation of the forest edges in the Kazakh Altai is the probable cause of the reduced epiphytic lichen diversity compared with the interior. The similar species richness in the forest interiors of the Kazakh and Mongolian Altai suggests that the differences at the forest edge are probably, at least partly, due to different land-use regimes and not to differences in macroclimate.     

Lichen conservation in Scotland

Summary

The significance of the Scottish lichen flora is outlined within the context of the British Isles and Europe, prompting a cautionary note on an over-reliance of assessing conservation importance using national Red Data Book categorisations. The conservation needs of lichens and their habitats, from ‘gardening’ to landscape management are discussed.     

PTP1B inhibitory effects of tridepside and related metabolites isolated from the Antarctic lichen Umbilicaria antarctica

The selective inhibition of PTP1B has been widely recognized as a potential drug target for the treatment of type 2 diabetes and obesity. In the course of screening for PTP1B inhibitory natural products, the MeOH extract of the dried sample of the Antarctic lichen Umbilicaria antarctica was found to exhibit significant inhibitory effect, and the bioassay-guided fractionation and purification afforded three related lichen metabolites 1-3. Compounds 1-3 were identified as gyrophoric acid (1), lecanoric acid (2), and methyl orsellinate (3) mainly by analysis of NMR and MS data. These compounds inhibited PTP1B activity with 50% inhibitory concentration values of 3.6 ± 0.04 μM, 31 ± 2.7 μM, and 277 ± 8.6 μM, respectively. Furthermore, the kinetic analysis of PTP1B inhibition by compound 1 suggested that the compound inhibited PTP1B activity in a non-competitive manner.     

ERUMPENT CEPHALODIA,AN APPARENT CASE OF PHYCOBIAL INFLUENCE ON LICHEN MORPHOLOGY1,2,3

On the upper surface of some specimens of the lichen Lobaria cf. crosa (Eschw.) Nyl. there are shrub-like growths which have a morphology similar to that of a free-living fruticose lichen, Polychidium umhausense (Auersw.) Henss., and contain a cyanophyte phycobiont, Nostoc. A few growths also contain scattered colonies of a chlorophyte phycobiont, in which case the lichen tissue locally assumes the foliose form characteristic of the parent Lobaria thallus. The differentiation of dorsiventral lichen cortices and the formation of a lax medulla and distinct algal layer are correlated with the presence of the green phycobiont. The lichen substances atranorin, gyrophoric acid, and 4-0-methylgyrophoric acid occur in both, the foliose L. erosa thallus and the fruticose tissue. It is suggested that the fruticose structures are erumpent cephalodia which are derived from the outgrowth of internal, cephalodia and should not be considered, to be epiphytic colonies of the lichen Polychidium.     

安徽省县级公立医院参与远程会诊情况调查分析

目的 分析安徽省县级公立医院信息化基本建设情况、医务人员参加远程会诊的意愿及其影响因素,为推进远程会诊持续发展提供意见。方法 通过文献复习,初步设计了远程会诊调查表,以无记名方式对安徽省8家开展远程会诊的县级公立医院进行调查。结果 （1）8家县级医院的信息化建设各不相同。（2）8家县级医院医务人员对远程会诊知晓率为76.2%。（3）对远程会诊相关问题理解不同,使用远程会诊意愿也不用。结论 从提高县级医院信息化平台建设,加强远程会诊宣传工作,以点带面,推进远程会诊发展,创新远程会诊服务模式等方面入手,提高县级公立医院和医务人员的参与度。     

A Lichen Substance as an Antiproliferative Compound against HL-60 Human Leukemia Cells: 16-O-Acetyl-leucotylic Acid Isolated from Myelochroa aurulenta

The lichen substance, 16-O-acetyl-leucotylic acid (1), was isolated from an acetone extract of Myelochroa aurulenta and found to exhibit antiproliferative activity against HL-60 human leukemia cells. This is the first report on its anti-leukemia activity (EC₅₀=21 μM) which is greater than that of leucotylic acid (2) and the structurally related anti-tumor agent, betulinic acid (4).     

Report of the Annual Conference of the Cryptogamic Section, 1948

Background: Trait-based assembly rules are a powerful tool in community ecology, used to explore the pattern and process of community structure (richness and composition).

Aims: A preliminary test for the utility of trait-based assembly rules in explaining cryptogamic epiphyte communities (lichens and bryophytes).

Methods: We sampled epiphytes from three different tree species (aspen, birch and pine), and from trees of contrasting age. The community composition of epiphyte species (taxon analysis) and functional groups (trait analysis) was summarised using multivariate ordination (nonmetric multidimensional scaling, NMDS).

Results: Ordination documented a widely observed pattern in which different tree species have taxonomically different epiphyte communities. However, NMDS sample scores were correlated to tree age in the trait-based analysis, but not in the taxon analysis.

Conclusions: Our results point to the existence of a common pattern in community traits during succession (on trees of different age) when measured for epiphyte communities with contrasting taxonomic composition. This pattern is evidenced by consistent trends in lichen growth form and reproductive strategy (sexual vs. asexual).     

Differenze Ultrastrutturali Di Alcune Specie Di Trebouxia Poste in Condizioni Di Illuminazione Differenti

Abstract

Ultrastructural changes in some species of « Trebouxia » under different light conditions. — Some species of the phycobiont alga Trebouxia (Tr. decolorans and Tr. albulescens), both isolated and grown on synthetic medium and still in the lichen, were examined in order to study the effect of light on the plastid ultrastructures. The species isolated from Buellia punctata and Xanthoria parietina were very sensitive to light condition and lost their chlorophyll content quickly. Striking ultrastructural changes were found in the algae grown under small light intensities and those which become achloric owing to strong light. In the latter, modifications of the Iamellar System were observed. The disappearance of Chlorophyll pigments was followed by a reduced electron density of the whole Iamellar system, as if were lacking the Iipidic compounds which are usually present and absorb fixators and dyers, thus allowing a good view. On the contrary, normal light conditions did not affect cultures of Trebouxia humicola, a free living alga. In the chloroplasts of the phycobiont species, unlike in the free living alga, grana were very close and sometimes formed very thick masses towards the edge of the chloroplast. It could not be ascertained whether such changes corresponded to a different composition of the lipoproteic compounds of the lamellar system.

Xanthoria parietina could grow in very lighted environments with no damage of the algae present in its thallus. The lichen thalluses, under different light conditions, showed very different colourings: the overlighted ones were rusty-red and the shadowed ones deep green. The chlorophyll content of the lichen thalluses with various shades (table 1) were very similar. The ultrastructural changes induced by strong light intensities in the phycobiont algae, kept in the lichen, were very small in respect of those observed in the same algae isolated and grown on synthetic medium and concerned the Iamellar system and the pyrenoid, above all. The rusty-red lichen showed a great number of stromatic lamellae, often with a parallel trend, so as to simulate a Iamellar system not organized in grana and often presented groups of lamellae concentrically arranged. In the pyrenoid of the algae from rusty-red thalluses, compared with the green ones, a much greater number of electron dense masses was observed, which are very thick and occupy the whole stromatic portion of the pyrenoid. But the Chlorophyll content did not decrease. Unlike the results of PEVELING, we noted that the electron dense masses (cited by the Author as « osmiophilic plastoglobules) were visible even after fixation with permanganate; the different numbers of these globules might depend on environmental factors. The phycobiont alga, when in the lichen thallus, could perhaps support strong light intensities, because pigments or compounds formed with the mycobiont or by it alone prevented the photooxidation of chlorophyll. Hypothetically a relationship might exist between the sensitivity of the phycobiont algae to light intensities and the content in antraquinonic pigments in the lichen thallus. But also using filters with absorption maxima similar to those of these pigments, the « in vitro » cultures of the phycobiont algae became achloric in the same time as the control ones.

Some Authors had found in Trebouxia humicola a different relationship between Chlorophyll pigments and carotinoids from that observed in the phycobiont species and had ascribed to it the greater resistence to strong light of the free living alga. Pigments or other substances present in the mycobiont can have a protective action on the Chlorophyll content and on the ultrastructures. In the phycobiont algae the resistence to strong light might be explained by an exchange of compounds between mycobiont and phycobiont, ending with the structural changes of the pyrenoid.     

Ultrastructural effects of trace elements and environmental pollution in Italian “Triangle of Death” on Pseudevernia furfuracea (L.) Zopf

Abstract

The lichen Pseudevernia furfuracea was exposed to environmental trace elements in the district of Acerra (province of Naples, southern Italy), one of the points forming Italy's “Triangle of Death”. P. furfuracea thalli were exposed in bags at different sites for 6 months, periodically collected and examined by transmission electron microscopy (TEM) to assess ultrastructural changes. An our earlier study demonstrated that these exposed lichens were strongly contaminated by trace elements (Sorbo S, Aprile G, Strumia S, Castaldo Cobianchi R, Leone A, et al. 2008. Trace element accumulation in P. furfuracea (L.) Zopf exposed in Italy's so-called Triangle of Death. Sci Total Environ 407: 647–654.). The algal cells were more affected than the fungal symbiont. Exposition at urban sites gave the most frequent changes. Four trace elements (Cd, Pb, Cu and Zn) were used to study the effects of ultrastructural trace element both in field and in vitro treatments. The lichen developed comparable ultrastructural changes when exposed to different trace elements and the changes were not specific to the treatment used (lichen bag exposition, in field and in vitro treatments). The in vitro treatment gave the highest frequency of damage at all time points. X-ray TEM microanalysis revealed trace elements inside the cell walls and the cytoplasmic vesicles of the lichens cultured with the trace elements; this localization is probably related to tolerance mechanisms.     

Low proportions of folic acid deficiency after introduction of mandatory folic acid fortification in remote areas of northern Queensland,Australia: a secondary health data analysis

Abstract

Background: Australia implemented mandatory folic acid fortification of bread-making flour in 2009.

Objective: To assess the impact of folic acid fortification in remote vs. regional urban areas and Indigenous vs. non-Indigenous populations in northern Queensland.

Methods: Routinely collected data on folic acid measurements in remote areas and two regional urban centres in northern Queensland between 2004 and 2015 were analysed (n?=?13,929) dichotomously (folic deficient vs. non-deficient).

Results: Overall prevalence of folic acid deficiency was 3.2% (235/7282) in urban centres compared with 7.2% (480/6647) in remote areas (p?<?0.001), and 9.3% (393/4240) in the Indigenous population compared with 3.2% (273/8451) in the non-Indigenous population (p?<?0.001). Prevalence of folic acid deficiency dropped from 12.2% (n?=?481) in 2004–2008 to 1.5% (n?=?126) in 2010–2015 (p?<?0.001). This translates into a relative risk reduction (RRR) of 88%. RRR was 79% (7.2% vs. 1.5%) in urban centres, 91% (17.3% vs. 1.5%) in remote areas, 92% (20.5% vs. 1.6%) in the Indigenous population and 80% (7.4% vs. 1.5%) in the non-Indigenous population (p?<?0.001 for all).

Conclusions: Substantial declines of folic acid deficiency to low and comparable proportions in former high-risk populations indicate that mandatory folic acid fortification of flour has had a population-wide benefit in northern Queensland.     

MOLECULAR STRUCTURAL STUDIES OF LICHEN SUBSTANCES WITH ANTIMICROBIAL,ANTIPROLIFERATIVE, AND CYTOTOXIC EFFECTS FROM Parmelia subrudecta

Lecanoric acid (1), orsellinic acid methyl ester (2), orcinol (3), and usnic acid (4) were isolated from the lichen Parmelia subrudecta, collected on Palma of the Canary Islands, Spain. Compounds 1, 2, 3, and 4 were purified by solvent extraction, silica gel column chromatography, and preparative high-performance liquid chromatography (HPLC) consecutively. The structures of the four compounds were elucidated by one- and two-dimensional nuclear magnetic resonance (NMR) experiments and mass spectrometric investigations. These compounds showed activity against important gram-positive and gram-negative pathogens like mycobacteria and multiresistant staphylococci. This activity is combined with antiproliferative activity and cytotoxicity.     

中国石蕊科地衣研究之三 中国新记录属:扇盘衣属

本文报道了主要分布于澳洲的扇盘衣属地衣,缝裂扇盘衣在中国的首次发现,从而为中国地衣区系增加了一个新记录属。文中报道的该属的地衣不仅在中国,即使在世界范围也十分珍异。因而,对于该属及种的特征从形态学、解剖学与化学方面给以简要描述。     

Lipid and Fatty Acid Composition of Tree-Growing and Terrestrial Lichens

A comparison of lipid and fatty acid composition was made of the tree-growing lichens Evernia prunastri (L.) Ach., Parmelia saxatilis (L.) Ach. and Hypogymnia physodes (L.) Ach. and the terrestrial species Cetraria islandica (L.) Ach. and Cladonia impexa Harm. In the terrestrial species the total lipid content varied strongly during spring, while the tree-growing species showed much less variation. Phospholipid and sterol content of all lichens was unusually low. Monoglycosyl diglyceride was absent from Parmelia saxatilis. Fatty acids common to higher plants as palmitic, stearic, oleic, linoleic and linolenic acid were invariably present in all lichen species. In addition large quantities of extra-long chain fatty acids like behenic acid, eicosadienoic acid and cyclic aliphatic lichen acids were present in the terrestrial species. The degree of (poly) unsaturation decreased in the order Evernia prunastri, Parmelia saxatilis. Fatty acids common to higher plants as palmitic, stearic, impexa, which decrease was compensated by an increase in extralong chain fatty acids and lichen acids. It is suggested that the lichen acids are of adaptive value for lichen species growing in the terrestrial habitats, which were characterized by extreme diurnal temperature variations. Just as the polyunsaturated fatty acids, lichen acids guarantee at lower temperatures a high flexibility of the membranes involved, at the same time as they are less susceptible to photo-oxidation at the high daytime temperatures.     

Lichens — the biodiversity value of western woodlands

Summary

The Atlantic broad-leaved woodlands of Britain are of international renown for their lichen floras. They are inhabited by 517 lichens, representing 28.3% of the total lichen flora and 73.2% of all British woodland lichens, and they are the main habitat for 165 species. Of these, 31 have a marked southern distribution and do not reach Scotland, whereas 26 species are found in Scotland, but not England or Wales. Their British Red-listed species are outnumbered by the 86 species for which Britain has International Responsibility.

Within the Atlantic broad-leaved woodlands, only 30 lichens show a preponderance for oak. With the exception of some ancient oakwoods in southern England, a high lichen biodiversity is rarely dependent on a dominance of oak in the woodland canopy, more usually it is the result of a long ecological continuity, often a varied tree and shrub composition, a varied canopy density, and good air quality. Consequently, the oak stands within former ‘industrial’ woodlands have a much lower lichen biodiversity compared with woodlands that have a history as ‘pasture woodland’ or, as with some ravine woodlands, have otherwise escaped intensive management.

The life-history of an oak tree is considered in relation to the niches it provides for lichen colonisation with time. Some management scenarios are provided with the enhancement of the lichen interest of former ‘industrial’ oakwoods as an objective.     

Morphological and phylogenetic study of algal partners associated with the lichen-forming fungus <Emphasis Type="Italic">Tephromela atra</Emphasis> from the Mediterranean region

Recent DNA sequence analyses have revealed the diversity of algal partners in lichen symbioses. Although morphologically similar, different genetic lineages of photobionts are detected in wide geographic ranges of the same lichen fungal species. We studied the photobiont of the genus Trebouxia, which are known as partners of diverse lichen-forming fungal species in the Mediterranean region. We studied the phylogeny of these algae with a multilocus dataset including three loci: ITS, rbcL, and actin type I gene. The two lineages found, informally named Trebouxia sp. 1 and Trebouxia sp. 2, are related to Trebouxia arboricola/decolorans. The cultivation under axenic conditions succeeded only for one of them so far. We used light microscopy, confocal laser scanning microscopy and transmission electron microscopy for phenotypic characterisation. The ultrastructural characters currently used to describe species in the genus do not support the segregation of Trebouxia sp.1 from Trebouxia arboricola. The preferential presence in Mediterranean climates of these strains suggests eco-physiological adaptation. Despite their asexuality in long living lichen symbioses, coccoid algal lichen partners have apparently diversified genetically and physiologically.     

Host use of a specialist lichen-feeder: dealing with lichen secondary metabolites

Host use by herbivores is largely determined by host properties such as nutrient content and chemical defence against foragers. The impacts of these attributes on a herbivore may largely depend on its life cycle stage. Lichen species are known to differ in nutritional quality and level of chemical defence and, consequently, vary as fodder for herbivores. The aim of this study was to explore the impact of several lichen species and the presence of their secondary metabolites on their use as hosts by a specialist lichen-feeder, Cleorodes lichenaria. This study also addressed, for the first time, how a specialist lichen-feeder deals with different lichen secondary metabolites. In the beginning of their development, larvae grew better on Xanthoria parietina than on the other host lichens, whereas older larvae grew best on Ramalina fraxinea. Lichen secondary chemicals in R. fraxinea and Parmelia sulcata hindered larval growth in the beginning but after 75 days lichen secondary chemicals had no impact on the mass of larvae. Physodic acids in Hypogymnia physodes were lethal to larvae. In general, larvae metabolized 70–95% of ingested lichen secondary chemicals and the rest of these were excreted in frass. Lichen secondary metabolites in P. sulcata restrict and in H. physodes prevent their use as a host for C. lichenaria larvae. Our main finding, the ability of larvae to metabolize several lichen secondary metabolites, indicates digestive adaptation to these chemicals. No signs of sequestration of these chemicals were found.