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Bark
Kinds of Bark Terms modified by Bark Selected AbstractsHost specificity of ambrosia and bark beetles (Col., Curculionidae: Scolytinae and Platypodinae) in a New Guinea rainforestECOLOGICAL ENTOMOLOGY, Issue 6 2007JIRI HULCR Abstract 1.,Bark and ambrosia beetles are crucial for woody biomass decomposition in tropical forests worldwide. Despite that, quantitative data on their host specificity are scarce. 2.,Bark and ambrosia beetles (Scolytinae and Platypodinae) were reared from 13 species of tropical trees representing 11 families from all major lineages of dicotyledonous plants. Standardised samples of beetle-infested twigs, branches, trunks, and roots were taken from three individuals of each tree species growing in a lowland tropical rainforest in Papua New Guinea. 3.,A total of 81 742 beetles from 74 species were reared, 67 of them identified. Local species richness of bark and ambrosia beetles was estimated at 80,92 species. 4.,Ambrosia beetles were broad generalists as 95% of species did not show any preference for a particular host species or clade. Similarity of ambrosia beetle communities from different tree species was not correlated with phylogenetic distances between tree species. Similarity of ambrosia beetle communities from individual conspecific trees was not higher than that from heterospecific trees and different parts of the trees hosted similar ambrosia beetle communities, as only a few species preferred particular tree parts. 5.,In contrast, phloeophagous bark beetles showed strict specificity to host plant genus or family. However, this guild was poor in species (12 species) and restricted to only three plant families (Moraceae, Myristicaceae, Sapindaceae). 6.,Local diversity of both bark and ambrosia beetles is not driven by the local diversity of trees in tropical forests, since ambrosia beetles display no host specificity and bark beetles are species poor and restricted to a few plant families. [source] Two Novel 14-Nor-13,14-secopodocarpanes from the Bark of Taiwania cryptomeriodesHELVETICA CHIMICA ACTA, Issue 2 2004Shih-Chang Chien The two novel compounds cryptomelactones A (3) and B (4) were isolated from the bark of Taiwania cryptomeriodes, besides the two known podocarpane derivatives 1,,13,14-trihydroxypodocarpa-8,11,13-trien-7-one (1) and 3,,13,14-trihydroxypodocarpa-8,11,13-trien-7-one (2), and were characterized by spectroscopic means including 2D-NMR techniques. Compounds 3 and 4 are novel-14-nor-13,14-seco-podocarpanes. The absolute configurations of 3 and 4 were determined by the modified Mosher method. The biotransformation mechanism of 3 and 4 is proposed. [source] Bark beetle-mediated fungal infections of susceptible trees induce resistance to subsequent infections in a dose dependent mannerAGRICULTURAL AND FOREST ENTOMOLOGY, Issue 3 2009Nadir Erbilgin Abstract 1,Experiments were conducted to determine whether propagule loads on the twig beetles Pityophthorus setosus and Pityophthorus carmeli (Coleoptera: Scolytidae) influence the pathogen infection of the host tree in the Monterey pine- Fusarium circinatum system. 2,On an average, F. circinatum was isolated from 2.6% and 3.3% of trapped P. setosus and P. carmeli, respectively, although the isolation percentages varied over the season, being highest in the spring and lowest in late summer and fall for both species. Mean pathogen load was 13.4 and 22.6 propagules per beetle, on P. setosus and P. carmeli, respectively, and decreased from May to November for both species. The pathogen was also isolated from approximately 55% of both beetle species that emerged from infected branches. Mean propagule load on emerged P. setosus and P. carmeli was 39 and 66.5, respectively. 3,On the basis of these data, beetle species were treated with one of three propagule loads (low, medium, high) and caged onto live branches to determine whether they could transmit the pathogen. At all propagule loads, both species transmitted the pathogen, and transmission percentage and lesion length, a measure of tree susceptibility, were positively correlated with propagule load. 4,To investigate further whether the previous transmission by beetles could affect response of the same trees to subsequent infection with F. circinatum, different branches were inoculated on the same trees used in the transmission study, and lesion lengths were measured. Lesion lengths were lower on trees that had been previously exposed to beetles treated with high or medium propagule loads than on trees that had previously been exposed to beetles treated with low propagule loads. This suggests that the initial infection by beetles carrying high or medium propagule loads induced resistance to subsequent infections of the host, whereas infections caused by beetles with low propagule loads did not. [source] The Anxiolytic Effect of Two Oriental Herbal Drugs in Japan Attributed to Honokiol from Magnolia BarkJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 11 2000HISASHI KURIBARA An improved elevated plus-maze test in mice revealed that seven daily treatments with two differnt traditional Chinese medicines, known as Kampo medicines in Japan, Hange-koboku-to (composed of extracts of 5 plants) and Saiboku-to (composed of extracts of 10 plants), produced an anxiolytic effect, and the effect was mainly due to the presence of honokiol derived from magnolia. This study was carried out to evaluate the anxiolytic potential of honokiol, Hange-koboku-to and Saiboku-to, which were prescribed with two different magnolia samples: Kara-koboku (Magnoliae officinalis) (KA) or Wa-koboku (Magnoliae obovata) (WA). The doses of test samples were adjusted to ensure a constant dose of honokiol at 0.2 mg kg,1. Although the doses of magnolol (an isomer of honokiol), as well as those of undetermined chemicals, varied among samples, the seven daily treatments with 9 out of 10 test samples produced an anxiolytic effect almost equivalent to that produced by 0.2 mg kg,1 honokiol. The only exception was the sample containing the lowest amount of honokiol. Magnolia-free preparations of Hange-koboku-to or Saiboku-to did not have any anxiolytic effect. These results confirm that honokiol derived from magnolia is the causal chemical of the anxiolytic effect of Hange-koboku-to and Saiboku-to. [source] French Maritime Pine Bark (Pinus maritima Lam.) Extract (Flavangenol®) Prevents Chronic UVB Radiation-induced Skin Damage and Carcinogenesis in Melanin-possessing Hairless MicePHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 4 2010Yoshiyuki Kimura A French maritime pine bark extract, Flavangenol®, is widely used as a nutritional supplement for protection against atherosclerosis, hypertension, diabetes, etc. Chronic exposure to solar UV radiation damages skin, increasing cutaneous thickness, wrinkling and pigmentation, as well as reducing elasticity, and causes skin cancer. The aim of this study was to examine the effects of flavangenol on skin damage and the incidence of skin tumors caused by long-term UVB irradiation in melanin-possessing hairless mice. The oral administration of flavangenol (60, 200 or 600 mg kg,1, twice daily) significantly inhibited increases in skin thickness, and the formation of wrinkles and melanin granules, as well as increases in the diameter and length of skin blood vessels. Furthermore, it prevented increases in numbers of apoptotic, Ki-67-positive and 8-hydroxy-2,-deoxyguanosine (8-OHdG)-positive cells, and the expression of skin vascular endothelial growth factor (VEGF) induced by chronic UVB irradiation. The effect on these biomarkers was associated with a reduction in the incidence of tumors in mice. The antiphotoaging and anticarcinogenetic activities of flavangenol may be due to inhibition of the expression of Ki-67, 8-OHdG and VEGF through a scavenging effect on reactive oxygen species. [source] The Dog That Did Not Bark: Insider Trading and CrashesTHE JOURNAL OF FINANCE, Issue 5 2008JOSE M. MARIN ABSTRACT This paper documents that at the individual stock level, insiders' sales peak many months before a large drop in the stock price, while insiders' purchases peak only the month before a large jump. We provide a theoretical explanation for this phenomenon based on trading constraints and asymmetric information. A key feature of our theory is that rational uninformed investors may react more strongly to the absence of insider sales than to their presence (the "dog that did not bark" effect). We test our hypothesis against competing stories, such as insiders timing their trades to evade prosecution. [source] Anti-Inflammatory and Analgesic Activities of the Aqueous Extract of Acacia karroo Stem Bark in Experimental AnimalsBASIC AND CLINICAL PHARMACOLOGY & TOXICOLOGY, Issue 5 2008Adeolu A. Adedapo The extract at 100 and 200 mg/kg reduced significantly the formation of oedema induced by carrageenan and histamine. In the acetic acid-induced writhing model, the extract showed a good analgesic effect characterized by a significant reduction in the number of writhes with two doses (100 and 200 mg/kg) used when compared to the untreated control group. In the tail immersion test, the extract at the doses used (100 and 200 mg/kg) increased reaction time to pain after 30 min. of oral administration of the extract. Indomethacin at 10 mg/kg served as reference drug in all these tests. The results gave a scientific basis to the traditional uses of Acacia karroo mainly for wound poultices, eye treatments and cold remedies. [source] Sugar Recovery and Fermentability of Hemicellulose Hydrolysates from Steam-Exploded Softwoods Containing BarkBIOTECHNOLOGY PROGRESS, Issue 5 2001Abdel Boussaid The hemicellulose sugar recovery and ethanol production obtained from SO2 -catalyzed steam explosion of a mixed white fir (70%) and ponderosa pine (30%) feedstock containing bark (9% dry weight/dry weight) was assessed. More than 90% of the available hemicellulose sugars could be recovered in the hydrolysate obtained after steam explosion at 195 °C, 2.38 min, and 3.91% SO2, with 59% of the original hemicellulose sugars detected in a monomeric form. Despite this high sugar recovery, this hydrolysate showed low ethanol yield (64% of theoretical yield) when fermented with a spent sulfite liquor-adapted strain of Saccharomyces cerevisiae. In contrast, most hydrolysates prepared at higher steam explosion severity showed comparable or higher ethanol yields. Furthermore, the hydrolysates prepared from bark-free feedstock showed better fermentability (87% of theoretical yield) despite containing higher concentration of known inhibitors. The ethanol yield from the hydrolysate prepared from a bark-containing wood sample could be improved to 81% by an extra stage acid hydrolysis (121 °C for 1 h in 3% sulfuric acid). This extra stage acid hydrolysis and steam explosion at higher severity conditions seem to improve the fermentability of the hydrolysates by transforming certain inhibitory compounds present in the hydrolysates prepared from the bark-containing feedstock and thus lowering their inhibitory effect on the yeast used for the ethanol fermentation. [source] A New Pyranoacridone Alkaloid from the Bark of Medicosma subsessilis (Rutaceae).CHEMINFORM, Issue 21 2004Nguyen Tuan Minh Abstract For Abstract see ChemInform Abstract in Full Text. [source] New Oleanene (I) and Fernane-Type Triterpenes (II) from the Stem Bark of Betula pendula RothCHEMINFORM, Issue 1 2004H. M. Mukhtar Abstract For Abstract see ChemInform Abstract in Full Text. [source] Two New Constituents from the Bark of Holarrhena pubescens.CHEMINFORM, Issue 32 2003Bina Shaheen Siddiqui No abstract is available for this article. [source] Further Daphniphyllum Alkaloids with Insecticidal Activity from the Bark of Daphniphyllum macropodumMiq.CHEMISTRY & BIODIVERSITY, Issue 10 2009Zhen-Yu Li Abstract Two new Daphniphyllum alkaloids, macropodumines J and K (1 and 2, resp.), together with six known structurally related alkaloids, 3,8, were isolated from the bark of Daphniphyllum macropodumMiq. The structures of the new compounds 1 and 2 were elucidated on the basis of a comprehensive analysis of their spectroscopic and chemical data. Macropodumine J (1) contains a CN group which is relatively rare in naturally occurring alkaloids. All isolated compounds were tested for their insecticidal activities against a number of insect species. Daphtenidine C (5) is the most active compound against Plutella xylostella. This is the first report of insecticidal properties of Daphniphyllum alkaloids. [source] Cytotoxic Prenylated Phenolic Compounds from the Twig Bark of Garcinia xanthochymusCHEMISTRY & BIODIVERSITY, Issue 5 2007Quan-Bin Han Abstract Three new hydroxylated xanthones with prenyl or geranyl substituents, compounds 1,3, were isolated from the twig bark of Garcinia xanthochymus, along with the four known compounds 1,4,5,6-tetrahydroxy-7,8-diprenylxanthone (4), 1,3,5,6-tetrahydroxy-4,7,8-triprenylxanthone (5), garciniaxanthone E (6), and 6-prenylapigenin (7). Their structures were elucidated by extensive spectroscopic analysis, including 1D- and 2D-NMR as well as HR-MS experiments. All compounds showed moderate cytotoxicities against breast cancer (MDA-MB-435S) and lung adenocarcinoma (A549) cell lines, but lacked antifungal activity against Candida albicans. [source] Xanthones from the Bark of Garcinia xanthochymus and Their 1,1-Diphenyl-2-picrylhydrazyl Radical-Scavenging Activity,CHINESE JOURNAL OF CHEMISTRY, Issue 1 2009Fangfang ZHONG Abstract Five new xanthones, garcinenone A (1), B (3), C (4), D (7) and E (8), along with 7 known compounds were isolated from the EtOAc-soluble extract of the bark of Garcinia xanthochymus, and their structures were elucidated by spectroscopic methods, especially 2D-NMR techniques. Jacareubin (2), 1,4,6-trihydroxy-5-methoxy-7-(3-methyl-2-butenyl)xanthone (6), subeliptenone B (11) and symphoxanthone (12) were obtained from this plant for the first time. The isolated compounds exhibited potent antioxidant activity in the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging test with IC50 values in the 6.0,23.2 µmol/L. These results suggested that G. xanthochymus could be a promising rich source of natural antioxidant. [source] Acoustic Features of Female Chacma Baboon BarksETHOLOGY, Issue 1 2001Julia Fischer We studied variation in the loud barks of free-ranging female chacma baboons (Papio cynocephalus ursinus) with respect to context, predator type, and individuality over an 18-month period in the Moremi Game Reserve, Botswana. To examine acoustic differences in relation to these variables, we extracted a suite of acoustic parameters from digitized calls and applied discriminant function analyses. The barks constitute a graded continuum, ranging from a tonal, harmonically rich call into a call with a more noisy, harsh structure. Tonal barks are typically given when the signaler is at risk of losing contact with the group or when a mother and infant have become separated (contact barks). The harsher variants are given in response to large predators (alarm barks). However, there are also intermediate forms between the two subtypes which may occur in both situations. This finding is not due to an overlap of individuals' distinct distributions but can be replicated within individuals. Within the alarm bark category, there are significant differences between calls given in response to mammalian carnivores and those given in response to crocodiles. Again, there are intermediate variants. Both alarm call types are equally different from contact barks, indicating that the calls vary along different dimensions. Finally, there are consistent, significant differences among different individuals' calls. However, individual identity in one call type cannot directly be inferred from knowledge of the individuals' call characteristics in the other. In sum, the barks of female baboons potentially provide rich information to the recipients of these signals. The extent to which baboons discriminate between alarm and contact barks, and classify calls according to context and/or acoustic similarity will be described in a subsequent paper. [source] New Components Including Cyclopeptides from Barks of Christiana africana DC. (Tiliaceae)HELVETICA CHIMICA ACTA, Issue 6 2008Serge Michalet Abstract Phytochemical investigation of barks of Christiana africana led to the identification of cyclopeptide alkaloids, flavonoids, coumarinolignans, iridoids, sesquiterpenoids, and triterpenes. This plant was classified so far in the Tiliaceae family. This study was started while the genomic study of numerous specimens was described in order to establish new criteria for Malvales botanical classification. In the present work, twenty components were identified, belonging to the three major classes of secondary metabolites: alkaloids, phenols, and terpenes. In the first class, cyclopeptides are well-known compounds in Rhamnaceae and Sterculiaceae. Their presence in Malvaceae (in APG2 sensus) suggests a possible chemical link between the ex-Tiliaceae and the Malvaceae. [source] Arboreal substrates influence foraging in tropical antsECOLOGICAL ENTOMOLOGY, Issue 4 2010NATALIE A. CLAY 1. Physically complex substrates impart significant costs on cursorial central-place foragers in terms of time spent outside the nest and total distance travelled. Ants foraging in trees navigate varied surfaces to access patchy resources, thus providing an appropriate model system for examining interactions between foraging efficiency and substrates. 2. We expected that the speed of recruitment, body size distribution and species richness of foraging arboreal ants would differ predictably among common substrate types occurring on tropical tree trunks. We measured changes in ant abundance and species composition over time at baits placed on bare tree bark, moss-covered bark, and vine-like vegetation appressed to bark. We also measured average body size and body size frequency on the three substrate types. Ants discovered baits sooner and accumulated at baits relatively faster when using vine substrates as the primary foraging trail. Average body size was smaller on vine substrates than on bark. Experimental removal of vine and moss substrates nullified these differences. Contrary to our predictions, species richness and body size distributions did not differ among the three substrate types, due in part to the frequent presence of a few common ground-nesting species at baits on bare bark. 3. Our results collectively indicate that linear substrates facilitate access of foraging ants to patchy resources. Ant use of vine-like substrates appears to be opportunistic; vine use is not confined to certain species nor constrained by body size. [source] Host specificity of ambrosia and bark beetles (Col., Curculionidae: Scolytinae and Platypodinae) in a New Guinea rainforestECOLOGICAL ENTOMOLOGY, Issue 6 2007JIRI HULCR Abstract 1.,Bark and ambrosia beetles are crucial for woody biomass decomposition in tropical forests worldwide. Despite that, quantitative data on their host specificity are scarce. 2.,Bark and ambrosia beetles (Scolytinae and Platypodinae) were reared from 13 species of tropical trees representing 11 families from all major lineages of dicotyledonous plants. Standardised samples of beetle-infested twigs, branches, trunks, and roots were taken from three individuals of each tree species growing in a lowland tropical rainforest in Papua New Guinea. 3.,A total of 81 742 beetles from 74 species were reared, 67 of them identified. Local species richness of bark and ambrosia beetles was estimated at 80,92 species. 4.,Ambrosia beetles were broad generalists as 95% of species did not show any preference for a particular host species or clade. Similarity of ambrosia beetle communities from different tree species was not correlated with phylogenetic distances between tree species. Similarity of ambrosia beetle communities from individual conspecific trees was not higher than that from heterospecific trees and different parts of the trees hosted similar ambrosia beetle communities, as only a few species preferred particular tree parts. 5.,In contrast, phloeophagous bark beetles showed strict specificity to host plant genus or family. However, this guild was poor in species (12 species) and restricted to only three plant families (Moraceae, Myristicaceae, Sapindaceae). 6.,Local diversity of both bark and ambrosia beetles is not driven by the local diversity of trees in tropical forests, since ambrosia beetles display no host specificity and bark beetles are species poor and restricted to a few plant families. [source] Overwintering of the sycamore aphid, Drepanosiphum platanoidisENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 2-3 2002F.A. Wade Abstract Spatial and temporal aspects of overwintering in the holocyclic sycamore aphid Drepanosiphum platanoidis (Schrank) (Homoptera: Callaphididae) were investigated. Eggs of D. platanoidis were principally laid on trunks and branches of Acer pseudoplatanus L., at considerable distances from the buds. Trunks with rough bark, followed by branches with moderate roughness supported more overwintering eggs than the relatively exposed smooth surfaces of twigs and terminal buds. Eggs were aggregated on rough bark. Aspect had no effect on the number of eggs laid. Experimental manipulations varying ovipara densities showed intra-specific competition among oviparae for optimal oviposition sites. Overwintering egg mortality was a function of time, with the greatest mortality rate occurring in late winter. Egg mortality varied from 80.4% to 76.9% on trunks and 83.0% to 65.9% on branches in 1996 and 1997. [source] Selection of hibernation sites by Anthonomus pomorum: preferences and ecological consequencesENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 3 2000St. Toepfer Abstract The apple blossom weevil, Anthonomus pomorum (L.) (Coleoptera: Curculionidae), has a long period of aestivo-hibernation in the adult stage lasting from summer to early spring of the following year. Potential hibernation sites within an apple orchard consist of high-stem rough-bark trees or dwarf smooth-bark trees. Field release-recapture experiments in 2 consecutive years showed that 64 and 47% of the weevils remained in the vicinity of the release sites in an area of high-stem trees and dwarf trees, respectively. The dispersing weevils moved over an average distance of 5.5 m in the dwarf tree area, as compared to 3.8 m in the high-stem tree area. The prevalent direction of dispersal was along tree rows in both areas. Some weevils displayed, after release in mid-July, a directional dispersal to the adjacent forests. Others, released in the dwarf tree area, dispersed towards the area of high-stem rough-bark apple trees. Experiments simulating various hibernation sites demonstrated that the litter of dry leaves was the most preferred overwintering shelter, yielding a relatively high survival rate. Branches with rough bark ranked second, while branches with smooth bark, grass and pure soil were not favourable for overwintering. Flight tendency in newly emerged weevils of summer generation was significantly higher in June/July than in August/September. This corresponds to the dispersal behaviour in the field. The timing of spring colonisation of apple trees was similar for weevils overwintering within the orchard and for those from outside. These results suggest that modern, dwarf apple orchards offer unfavourable conditions for overwintering, but that the relatively small proportion of weevils which manage to reach the adjacent forests find optimal hibernation sites there. [source] Volatile oils from leaves and stem barks of Cedrela ,ssilis (Meliaceae): chemical composition and antibacterial activitiesFLAVOUR AND FRAGRANCE JOURNAL, Issue 5 2004João Henrique G. Lago Abstract The volatile oils from the leaves and stem barks of Cedrela ,ssilis were submitted to GC,MS analysis and separation by adsorption chromatography. The fractions were analysed by GC, 1H- and 13C-NMR as well as GC,MS. The major components found in the leaf oil were , -caryophyllene (26.3%) and bicyclogermacrene (34.6%), while in the stem bark oil the major compounds were , -bisabolene (10.9%) and globulol (10.9%). In an antibacterial assay, only the leaf oil was able to inhibit growth of Staphylococcus aureus and Eschorichia coli. Copyright © 2004 John Wiley & Sons, Ltd. [source] Chemical constituents of the essential oils of Goniothalamus malayanus Hook. f. and Thoms.FLAVOUR AND FRAGRANCE JOURNAL, Issue 5 2002Ibrahim bin Jantan Abstract The chemical composition of the leaf, bark and root oils of Goniothalamus malayanus Hook. f. and Thoms. was examined by capillary GC and GC,MS. The leaf oil was made up mainly of sesquiterpenoids, of which ,-selinene (33.6%) was the dominant component. The other major compounds present were viridiflorol (13.1%), epi -globulol (7.7%), (E)-nerolidol (4.4%) and globulol (3.8%). The bark and root oils, which were qualitatively similar but with some variation in levels of the individual constituents, were also rich in sesquiterpenoids (97% and 95%, respectively), with eudesmols as the most abundant compounds. The bark oil contained a higher amount of ,-eudesmol (32.2%), ,-eudesmol (21.8%) and ,-eudesmol (6.6%) than the root oil. Copyright © 2002 John Wiley & Sons, Ltd. [source] The Egyptian Eucalyptus camaldulensis var. brevirostris: chemical compositions of the fruit volatile oil and antioxidant activityFLAVOUR AND FRAGRANCE JOURNAL, Issue 4 2002Ahmed H. El-Ghorab Abstract The fruit volatile oil of E. camaldulensis var. brevirostris was isolated by hydrodistillation and thereafter the fruit marc was extracted by ethanol. The volatile oil obtained was subjected to analysis using gas chromatography,mass spectrometry. Thirty-eight volatile components were identified. The main volatile compounds in the fruit volatile oil were: aromadendrene (17.99%), ,-pinene (12.68%), p -cymenene (5.39%), ,-gurjunene (6.65%), cubenol (9.23%), thymol (1.62%) and p -cymen-7-ol (0.73%). The volatile components were classified into four groups: monoterpenes (20.6%), sesquiterpenes (33.8%), light-oxygenated (8.1%) and heavily-oxygenated (37.6%) compounds. The results showed that the concentration of sesquiterpenes and heavily-oxygenated compounds were higher than the other two classes. The main compound in the ethanol extract of fruit of E. camaldulensis was isolated by semi-preparative HPLC and identified as ellagic acid. The antioxidant activities of the fruits volatile oil and the ethanol extract as well as that of the tree bark were evaluated by the thiocyanate method. The ethanol extract of Eucalyptus fruit exhibited considerable activity compared with butylated hydroxyanisole (BHA) and tertiary butylated hydroquinone (TBHQ). The high inhibitory effect of the ethanol extract of fruit upon linoleic acid after 12 days might be related to the higher ellagic acid content. Copyright © 2002 John Wiley & Sons, Ltd. [source] Salix daphnoides (willow bark) extract and osteoarthritic and rheumatoid arthritic painFOCUS ON ALTERNATIVE AND COMPLEMENTARY THERAPIES AN EVIDENCE-BASED APPROACH, Issue 2 2005Article first published online: 14 JUN 2010 [source] PCR primers for identification of Sirococcus conigenus and S. tsugae, and detection of S. conigenus from symptomatic and asymptomatic red pine shootsFOREST PATHOLOGY, Issue 3 2008D. R. Smith Summary Regions of diversity in the internal transcribed spacer (ITS) sequences of Sirococcus species were exploited to design primer pairs used in a PCR-based method for the identification of the conifer shoot blight pathogen Sirococcus conigenus and the closely related fungus Sirococcus tsugae. The specificity of each primer pair for the respective fungus, detection limits and utility for detection from host material were confirmed. The S. conigenus primers were then used to detect this pathogen in tissues of symptomatic or apparently healthy red pine shoots collected at six locations in Wisconsin and Michigan and results compared with those obtained using a cultural assay. For needles, bark and wood of symptomatic shoots, the mean frequencies of detection of S. conigenus using the PCR-based methods were consistent (,7.5 out of 10) and always greater than for the cultural assay. Detection from symptomatic shoots using the cultural assay was more frequent from needles than from bark or wood. Both the PCR-based method and the cultural assay detected S. conigenus in similar frequencies from asymptomatic shoots, although less frequently than from symptomatic shoots. The efficiency of the PCR-based method and its utility for direct testing of host material should make it particularly useful in areas where multiple shoot blight pathogens are found. [source] Targeted gene analysis in Ulmus americana and U. pumila tissuesFOREST PATHOLOGY, Issue 2 2008C. Nasmith Summary Steady-state gene expression was compared between Dutch elm disease (DED)-susceptible Ulmus americana and DED-resistant U. pumila callus, leaf midrib, root and inner bark tissues. Stress-related cDNAs including phenylalanine ammonia-lyase (PAL), chitinase (CHT) and polygalacturonase-inhibiting protein (PGIP) were isolated and compared following RT-PCR of elm tissues. Complete CHT and partial PAL and PGIP cDNA transcripts were identified, each displaying sequence variation between elm species. These transcripts were Dig-labelled and subsequently used for northern analyses of the elm tissues. Midrib and root tissue displayed highest steady-state gene expression compared with inner bark and callus tissues. A modified nucleic acid isolation technique was necessary for downstream RNA analyses. Lithium chloride and polyvinylpyrrolidone were critical for efficient removal of polysaccharides and phenolics associated with some of the elm tissues. Steady-state gene expression is discussed in relation to the tissues investigated. The use of tissues other than in vitro callus culture more closely represents the tissues associated with the elm's vascular response to DED. [source] Seasonal effect on infection and development of lesions caused by Cryphonectria parasitica in Castanea sativaFOREST PATHOLOGY, Issue 4 2003L. Guérin Summary Seasonal variation in the development of chestnut blight, caused by Cryphonectria parasitica, was investigated by inoculating in situ chestnut trees and in vitro excised chestnut segments, at either monthly or 3-monthly intervals throughout 30 months. Inoculations were made with conidia and mycelium of a virulent isolate and with mycelium of a hypovirulent isolate. Conidial inoculations of living sprouts or excised segments between May and July resulted in the greatest incidence of infection whereas inoculations in autumn and winter, in vitro as well as in situ, did not reveal any visible disease. However, from these symptomless inoculated stems, C. parasitica was isolated 3 months after inoculation. Inoculations with the mycelium of the virulent isolate always resulted in lesions, except in January 1999, and the greatest rate of lesion development occurred for inoculations made in the spring and summer. There was a significant seasonal effect on lesion development. Lesions caused by the hypovirulent isolate, smaller than those caused by the virulent isolate, followed a similar seasonal pattern. The same seasonal variations were observed for inoculations in vitro of excised segments. Relative water content (RWC) of chestnut bark significantly varied with bark sampling date. The rate of lesion development in sprouts significantly correlated with average minimum (ATn) and maximum (ATx) temperatures and the sum of rainfall during inoculation period, with the rate of lesion development measured in excised segments 10 days after inoculation (R10d) and with RWC measured on the day of inoculation. In multiple regression models, variables ATx and R10d best explained variation in lesion development. Résumé La variation saisonnière du développement de la maladie du chancre causée par Cryphonectria parasitica a étéétudiée en réalisant, une fois par mois ou par trimestre pendant deux ans et demi, des inoculations de châtaigniers in situ et des inoculations in vitro de branches coupées. Les inoculations ont été réalisées avec des conidies et du mycélium d'un isolat virulent et avec du mycélium d'un isolat hypovirulent. En Mai et Juin, les inoculations conidiennes ont provoqué le taux d'infection le plus élevé, in situ et in vitro. A l'inverse, en automne et en hiver, ces inoculations n'ont pas causé de symptômes. Cependant C. parasitica a été réisolé 3 mois plus tard, sur ces tiges ne présentant aucune lésion. Les inoculations avec du mycélium ont toujours résulté en des lésions, excepté en Janvier 1999, et le développement des lésions (R1m) a été le plus rapide au printemps et en été. La date d'inoculation a eu un effet significatif sur l'extension des lésions. Le même effet saisonnier était observé sur le développement des lésions causées par l'isolat hypovirulent, plus petites que celles causées par l'isolat virulent. Les mêmes variations saisonnières de l'extension des lésions étaient observées in vitro sur tiges excisées. Un effet saisonnier significatif a été mis en évidence sur la teneur en eau relative des écorces de châtaignier (RWC). Le développement des lésions dans les tissus vivants était significativement corrélé avec les températures moyennes minimale (ATn) et maximale (ATx) et la somme des précipitations (SR) calculées sur chaque période d'incubation, avec le développement des lésions in vitro (R10d) et avec RWC. La variation saisonnière du développement des lésions était le mieux expliquée, par un modèle de régression multiple, par ATx et R10d pour l'isolat virulent, et par ATx pour l'isolat hypovirulent. Zusammenfassung Der jahreszeitlich bedingte Einfluß auf die Entstehung von Kastanienrindenkrebs, verursacht von Cryphonectria parasitica, wurde durch Inokulation von Kastanienbäumen in situ und durch Beimpfung von geschnittenen Triebsegmenten in vitro in monatlichen oder drei-monatlichen Intervallen über dreißig Monate untersucht. Zur Inokulation wurden Myzel und Konidien eines virulenten Isolates und Myzel eines hypovirulenten Isolates verwendet. Mit Konidien wurde zwischen Mai und Juni die größte Infektionshäufigkeit auf lebenden Sprossen oder Triebsegmenten erreicht, während Inokulationen im Herbst und Winter keine sichtbaren Symptome hervorriefen. Jedoch konnte C. parastica drei Monate nach Inokulation von lebenden Sprossen isoliert werden, auch wenn keine Läsion sichtbar war. Außer im Januar 1999 führte Inokulation mit Myzel des virulenten Isolates immer zu Läsionen. Am häufigsten traten Läsionen bei Inokulationen im Frühling und im Sommer auf. Der Einfluß des Inokulationszeitpunktes auf die Ausbildung von Läsionen war signifikant. Inokulationen mit dem hypovirulenten Isolat zeigten eine ähnliche jahreszeitliche Schwankung wie jene mit dem virulenten Isolat, führten aber zu kleineren Läsionen. Die gleichen jahreszeitlichen Variationen wurden bei in vitro Inokulation von Kastanientrieben beobachtet. Der relative Wassergehalt (RWC) der Borke variierte signifikant mit dem Beprobungszeitpunkt der Borke. Die Bildung von Läsionen an lebenden Sprossen korrelierte signifikant mit den durchschnittlichen Temperaturminima (ATn) und -maxima (ATx), mit der Gesamtregenmenge (SR) während der Inokulationsperiode, mit der Bildung von Läsionen an Triebsegmenten (R10d) und mit dem am Inokulationstag gemessenen RWC. In einem multiplen Regressionsanalysenmodell zeigte sich, dass die jahreszeitliche Schwankung der Ausbildung von Kastanienrindenkrebs beim virulenten Isolat am besten durch die Variablen ATx und R10d, beim hypovirulenen Isolat durch ATx erklärt wurde. [source] Lesion development in stems of rough- and smooth-barked Eucalyptus nitens following artificial inoculations with canker fungiFOREST PATHOLOGY, Issue 3 2001Z. Q. Yuan A study of lesion development in stems of Eucalyptus nitens following artificial inoculations with canker fungi was carried out on 16-year-old plantation trees. In a first trial cambium bark wounds on smooth- and rough-barked trees were inoculated with the mycelium of nine species of canker fungi, including Endothia gyrosa. In a second trial spores or mycelium of E. gyrosa were applied directly onto undamaged or superficially wounded bark surfaces. Infection subsequent to artificial inoculation via wounding (whatever the wounding technique or type of inoculum) resulted in significantly larger external lesions (mean lesion area up to 35.6 cm2 20 months after inoculation) on smooth bark compared with those on rough bark (up to 19.0 cm2). Microscopic studies of infected rough and smooth bark suggest that, once smooth bark is compromised by wounding and artificial inoculation, the particular anatomical structure of smooth bark may offer less mechanical resistance to post-penetration hyphal spread in comparison with rough bark. It is suggested that at a pre-penetration stage under natural conditions spores of E. gyrosa more easily infect rough bark via cracks associated with this type of bark but not present in smooth bark. Développement des lésions sur les troncs d'Eucalyptus nitens àécorce lisse ou rugueuse, après inoculation par des champignons agents de chancre L'étude a été conduite en plantation sur des arbres de 16 ans. Dans un premier essai, des blessures de l'écorce jusqu'au cambium sur des arbres àécorce lisse ou rugueuse, ont été inoculées avec le mycélium de 9 espèces de champignons agents de chancre, dont Endothia gyrosa. Dans un deuxième essai, des spores ou du mycélium de E. gyrosa ont été appliqués directement sur l'écorce intacte ou blessée seulement superficiellement. Quel que soit la technique d'inoculation ou le type d'inoculum, l'infection a été plus importante extérieurement (surface moyenne jusqu'à 35,6 cm2 après 20 mois) chez les écorces lisses que chez les rugueuses (jusqu'à 19,0 cm2). L'étude microscopique des écorces infectées suggérait qu'à condition que l'écorce lisse soit impliquée dans la blessure, sa structure anatomique particulière offre moins de résistance mécanique à la post-pénétration mycélienne que l'écorce rugueuse. Il est suggéré qu'au stade de la pré-pénétration en conditions naturelles, les spores de E. gyrosa infectent plus facilement l'écorce rugueuse à la faveur des fissures qui sont présentes chez ce type d'écorce mais absentes chez les écorces lisses. Entwicklung von Läsionen am Stamm von rauh- und glattrindigen Individuen von Eucalyptus nitens nach künstlicher Inokulation mit krebserregenden Pilzen Es wurde die Entwicklung von Läsionen an Stämmen 16jähriger Eucalyptus nitens -Pflanzungen nach künstlicher Inokulation mit Krebserregern untersucht. In einem ersten Versuch wurden an rauh- und glattrindigen Bäumen Rindenwunden, die bis zum Kambium reichten, mit Myzel von neun Arten krebserregender Pilze, einschliesslich Endothia gyrosa, beimpft. In einem zweiten Versuch wurden Sporen oder Myzel von E. gyrosa direkt auf unverletzte oder nur oberflächlich verletzte Rinde aufgebracht. Künstliche Inokulation von Wunden (unabhängig von der Methode der künstlichen Verwundung oder der Art des Inokulums) führte zu signifikant grösseren, äusseren Wunden auf glatter (durchschnittliche Läsionsfläche 35.6 cm2 20 Monate nach Inokulation) als auf rauher Rinde (bis 19.0 cm2). Mikroskopische Untersuchungen zeigten, dass glatte Rinde gegen die Ausbreitung von Pilzhyphen mechanisch weniger resistent ist als rauhe Rinde. Unter natürlichen Bedingungen dürften dagegen Sporen von E. gyrosa Bäume mit rauher Rinde leichter durch vorhandene Rindenrisse infizieren, die bei glatter Rinde fehlen. [source] Induced resistance of Norway spruce, variation of phenolic compounds and their effects on fungal pathogensFOREST PATHOLOGY, Issue 2 2000P. C. Evensen Summary Three clones of Norway spruce (Picea abies) were studied for their response to mass-inoculation with the blue-stain fungus Ceratocystis polonica. The effect of different pretreatments (fungal inoculation and wounding) before mass-inoculation was investigated for their possible role in an acquired resistance reaction. Pretreated trees showed enhanced resistance to the subsequent mass-inoculation relative to control trees that received no pretreatment. Furthermore, the fungal colonization of inoculated trees was less than that of wounded trees. The phenolic content of the bark, analysed by RP-HPLC, was compared in trees receiving different treatments. Trees inoculated with C. polonica had higher average concentration of (+)-catechin, taxifolin and trans-resveratrol than wounded trees. Both inoculated and wounded trees had higher average concentrations of these compounds than control trees. The effect of the phenolic extract of Norway spruce bark on the growth of the root rot fungus Heterobasidion annosum and the blue-stain fungi C. polonica and Ophiostoma penicillatum were investigated in vitro. Heterobasidion annosum was not negatively affected, and the extracts had fungistatic effects on the blue-stain fungi. The growth of O. penicillatum was more inhibited than the growth of the more aggressive C. polonica. [source] , -Cyclodextrin as Inhibitor of the Precipitation Reaction between Berberine and Glycyrrhizin in Decoctions of Natural Medicines: Interaction Studies of Cyclodextrins with Glycyrrhizin and Glycyrrhetic Acid by 1H-NMR Spectroscopy and Molecular-Dynamics CalculationHELVETICA CHIMICA ACTA, Issue 9 2008Miyoko Kamigauchi Abstract To prevent the precipitation reaction between glycyrrhizin (1) and berberine (3) in the decoctions of Glycyrrhiza/Coptis rhizome or Glycyrrhiza/Phellodendron bark, the presence of cyclodextrin (CD) in the mixture was proven to be effective. The preventing effect decreased in the order , -CD>, -CD, and no effect was observed for , -CD. On the other hand, the extraction degree of 1 from the natural medicine Glycyrrhia was considerably increased in the presence of , -CD, , -CD being much more effective than , - or , -CD. Thus, the blocking effect of CD on the precipitate formation between 1 and 3 is suggested to be primarily dependent on the stability of the inclusion complex of the CD with 1. To establish the structure of such a preferred inclusion complex, the interactions of 1 with , - and , -CDs were investigated by 1H-NMR spectroscopy and molecular-dynamics (MD) calculations. The 1H-NMR measurements showed that the increase in solubility of 1 in H2O is dependent on the degree of its inclusion into the CD, which depends on the molecular size of the CD. The MD calculations suggested that the H-bond interactions are sufficiently strong to form a stable [1/, -CD] complex, in which the lipophilic rings C, D, and E of 1 are fully inserted into the molecular cavity of , -CD, thus forming a kind of structure covered by a hydrophilic molecular capsule, while such an interaction mode is impossible for , - or , -CD. [source] | |||||||||||||||||||||||||||||||||||||||||||