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At least 19 recordsLinked to original sources

Allergic rhinitis to thuja pollen.

Allergy to pollen of Cupressaceae has been linked to pollens of Cupressus, Juniper and Cryptomeria. The authors report 2 cases of rhinitis and conjunctivitis induced by thuja, another member of the Cupressaceae family. Monosensitization to thuja pollen has been identified as the causal agent: (1) of a long-standing springtime rhinitis in 1 patient with negative skin tests and specific IgE titers to the main inhalants (specificity of the prick test and nasal provocation with the thuja extract was confirmed by a positive RAST) and (2) in a 2nd patient without former history of allergy, who consulted for conjunctivitis following acquisition of a dog; the standard battery of skin tests, and Phadiotop were all negative. After controls, only the thuja extract gave significant skin test response. The level of total IgE was low, and RAST was negative. Sensitization and pollen provocation were produced by the intermediary of the dog, carrying thuja pollens on its fur. The immunoprint and the crossed radioimmunoelectrophoresis revealed common antigenicity between cypress and thuja extracts.

Adult↗

GC analysis of essential oils in the rumen fluid after incubation of Thuja orientalis twigs in the Rusitec system.

Methods for the chemical analysis of toxic plant substances in the rumen of ruminants are of importance for the diagnosis of intoxications with poisonous plants. The present work establishes a method to estimate monoterpene components of the essential oil of thuja (Thuja orientalis, Cupressaceae) in these types of samples. Alpha-thujone, which is regarded as the toxic principle, is present at a concentration of 50-60% in the essential oil. The rumen simulation technique (Rusitec) was used to simulate natural digestion. Chopped twigs of thuja were subjected to rumen content in a closed container with an overflow device. The flow of saliva was simulated by the continuous addition of a buffer solution. Samples for analysis were taken from the overflow at 24 and 48 h. A further sample was taken from the remaining liquid fraction of the rumen content in the container at 48 h. The essential oils were extracted with hexane and concentrated. A quantitative determination was done by capillary gas chromatography. Together in the three fractions analysed this resulted in total mean recoveries of 6.8% for alpha-thujone, 5.3% for beta-thujone, 18.9% for fenchone and 27.8% for camphor. The observation that the thujones were recovered to a lesser extent than other oil components is evidence of their fast decomposition in the rumen medium. Under these circumstances the calculated detection limit is 100-200 g thuja twigs in cows with rumen volumes of 60-100 litres. The main essential oil degradation products found in the rumen fluid of all three fractions in the Rusitec system were discovered to be iso-3-thujanol, neo-3-thujanol, carvomenthol and carvomenthone.

Animals↗

Thuja occidentalis (Arbor vitae): A Review of its Pharmaceutical, Pharmacological and Clinical Properties.

Arbor vitae (Thuja occidentalis L.) is a native European tree widely used in homeopathy and evidence-based phytotherapy. Many reviews and monographs have been published on the herbal substance's description, mode of action and clinical use. However, no comprehensive evidence-based review is available. Therefore, our aim was to search MEDLINE databases and survey manufacturers for further details or unpublished data. This review presents the botany, ethnobotany and phytochemistry, especially the different contents of essential oil (Thujone) in relation to different extraction procedures of this medicinal plant. Thuja's antiviral action and immunopharmacological potential, such as stimulatory and co-stimulatory effects on cytokine and antibody production and activation of macrophages and other immunocompetent cells, have been evaluated in numerous in vitro and in vivo investigations. Although no controlled trials have been conducted on Thuja occ alone, many clinical studies have been performed with a herbal medicinal product containing a special extract of Thuja occ and other immunostimulants, demonstrating its therapeutic efficacy and safety in respiratory tract infections.

Journal Article↗

Contact allergy from Frullania and respiratory allergy from Thuja.

Occupational allergic contact dermatitis in 52 forest-workers was caused by sesquiterpene lactones from liverworts (Frullania) and by usnic acid from lichens which grow on various trees including cedar (Thuja). Occupational asthma and rhinitis in 35 wood-workers was caused by wood dust of western red cedar (Thuja plicata). Characteristically, the respiratory symptoms occurred in the evening and at night and not during working hours; inhalation challenge with plicatic acid from the wood provoked immediate, late or dual (combined immediate and late) asthmatic reactions. Another class of compounds, tropolones, derived from Thuja plicata wood, was responsible for dermatitis in a wood-worker. These distinct industrial hazards in two groups of workers at the tree-felling and wood-working levels in the forest-products industry can be identified by clinical history and examination supplemented by specific cutaneous or respiratory clinical investigation.

Alcohols↗

Branch and foliage morphological plasticity in old-growth Thuja plicata.

At the Wind River Canopy Crane Facility in southeastern Washington State, USA, we examined phenotypic variation between upper- and lower-canopy branches of old-growth Thuja plicata J. Donn ex D. Don (western red cedar). Lower-canopy branches were longer, sprouted fewer daughter branches per unit stem length and were more horizontal than upper-canopy branches. Thuja plicata holds its foliage in fronds, and these had less projected area per unit mass, measured by specific frond area, and less overlap, measured by silhouette to projected area ratio (SPARmax), in the lower canopy than in the upper canopy. The value of SPARmax, used as an indicator of sun and shade foliage in needle-bearing species, did not differ greatly between upper- and lower-canopy branches. We suggest that branching patterns, as well as frond structure, are important components of morphological plasticity in T. plicata. Our results imply that branches of old-growth T. plicata trees have a guerilla growth pattern, responding to changes in solar irradiance in a localized manner.

Light↗

Occupational asthma caused by eastern white cedar (Thuja occidentalis) with demonstration that plicatic acid is present in this wood dust and is the causal agent.

A worker developed symptoms of work-related asthma a few weeks after starting to work in a sawmill where eastern white cedar (Thuja occidentalis) was transformed into shingles. The diagnosis of occupational asthma was confirmed by monitoring of peak expiratory flow rates and bronchial responsiveness to histamine off work and at work, and specific inhalation challenges in the laboratory that demonstrated an isolated late asthmatic reaction after exposure for 4 hours to the wood dust. Specific inhalation challenges with western red cedar (thuja plicata) for 2 hours and plicatic acid (PA) for 7 minutes also caused an isolated late asthmatic reaction. Elevated specific IgE levels to PA were present. Antiserum was produced in rabbits that were immunized with PA conjugated to human serum albumin. With this antiserum in inhibition experiments, cross-reactivity between western red cedar and eastern white cedar, both belonging to the family of arborvitae, was found. It is estimated that eastern white cedar contains approximately half the amount of PA present in western red cedar.

Adult↗

Thuja plicata exclusion in ectomycorrhiza-dominated forests: testing the role of inoculum potential of arbuscular mycorrhizal fungi.

The ability of trees dependent on arbuscular mycorrhizal (AM) fungi to establish in ectomycorrhizal forests is unknown. On northern Vancouver Island, Canada, there are sharp boundaries between mixed red cedar (Thuja plicata)-hemlock (Tsuga heterophylla) (CH) stands, and stands of hemlock and amabilis fir (Abies amabilis) (HA). We tested differences in AM colonization of red cedar between ectomycorrhiza-dominated (HA) stands and stands containing red cedar (CH), across a range of light levels. We used a soil bioassay approach to determine whether there was sufficient AM fungal inoculum in the HA tree stands to colonize red cedar seedlings. Seeds of hemlock and red cedar were sown in forest floor samples collected from the two types of forests, and shade treatments ranging from < 1 to 53% of full sunlight were imposed. After 6 months, seedling survival and root and shoot biomass were quantified, and red cedar seedlings were sampled for AM fungal colonization. Hemlock survival and growth did not differ between soil types, suggesting there was no substrate-associated limitation to its establishment in either forest type. Red cedar colonization by AM fungi was significantly correlated with light levels in CH soils but arbuscular mycorrhizas were absent in roots of red cedar seedlings grown in HA soil. Red cedar survival and relative growth rate were significantly greater in the CH than in HA soil; higher growth was due primarily to greater shoot growth in CH soils at high light levels. The low soil inoculum potential for red cedar in ectomycorrhiza-dominated stands may account for the virtual exclusion of red cedar seedlings from these forests.

Abies↗

The extract of Thujae occidentalis semen inhibited 5alpha-reductase and androchronogenetic alopecia of B6CBAF1/j hybrid mouse.

BACKGROUND: The conversion of testosterone to dihydrotestosterone; 5alpha-androstan-17beta-ol-3-one by 5alpha-reductase plays a crucial role in hair baldness and prostatomegaly. Recent approach showed specific inhibitors for 5alpha-reductase type 2 such as finasteride promoted hair growth in male pattern alopecia. OBJECTIVE: In order to search for effective medicinal plant extracts applied topically for androgenetic alopecia, we screened natural plant extracts having inhibitory activities of 5alpha-reductase type 2 and demonstrated its biological function in androgen-related animal models. METHODS: We evaluated the inhibition activities of numerous plant extracts by contact cell based metabolic method using a stable HEK 293 cell line expressing human 5alpha-reductase (type 2). To elucidate the biological activity in vivo, the Thujae occidentalis semen (TOS) extract was topically applied to fuzzy rat and androchronogenetic alopecia (AGA) mouse, respectively. The secreted sebum and the size of sebaceous glands of fuzzy rat were measured after 6 weeks. Also, after the topical treatment with TOS extract and androgen receptor antagonist (cyproterone acetate) simultaneously with subcutaneous injection of testosterone (1 mg/mice/day), hair loss patterns of female B6CBAF1/j hybrid mouse were observed. RESULTS: TOS extract showed higher inhibition activity of 5alpha-reductase type 2(IC(50) value=2.6 microg/ml) than that of gamma-linolenic acid, but lower than that of finasteride. When applied to fuzzy rat, the amount of sebum and sebaceous gland size decreased remarkably. In AGA model, alopecia degrees of two groups, treated with TOS extract (P<0.015) or cyproterone acetate (P<0.01), were lower than that of vehicle (propylene glycol:ethanol=7:3) and there was no difference between above two groups. CONCLUSION: We have demonstrated the inhibitory activity of TOS extract for 5alpha-reductase type 2 and its biological action in two animal models, suggesting that TOS extract would be used as an effective agent for male pattern baldness by modifying androgen conversion.

3-Oxo-5-alpha-Steroid 4-Dehydrogenase↗

The western red cedar (Thuja plicata) 8-8' DIRIGENT family displays diverse expression patterns and conserved monolignol coupling specificity.

The isolation and characterization of a multigene family of the first class of dirigent proteins (namely that mainly involved in 8-8' coupling leading to (+)-pinoresinol in this case) is reported, this comprising of nine western red cedar (Thuja plicata) DIRIGENT genes (DIR1-9) of 72-99.5% identity to each other. Their corresponding cDNA clones had coding regions for 180-183 amino acids with each having a predicted molecular mass of ca. 20 kDa including the signal peptide. Real time-PCR established that the DIRIGENT isovariants were differentially expressed during growth and development of T. plicata (P < 0.05). The phylogenetic relationships and the rates and patterns of nucleotide substitution suggest that the DIRIGENT gene may have evolved via paralogous expansion at an early stage of vascular plant diversification. Thereafter, western red cedar paralogues have maintained an high homogeneity presumably via a concerted evolutionary mode. This, in turn, is assumed to be the driving force for the differential formation of 8-8'-linked pinoresinol derived (poly)lignans in the needles, stems, bark and branches, as well as for massive accumulation of 8-8'-linked plicatic acid-derived (poly)lignans in heartwood.

Amino Acid Sequence↗

Aromatase inhibitory activities of standishinal and the diterpenoids from the bark of Thuja standishii.

The absolute stereostructure of a novel skeletal diterpene, standishinal (1), from the bark of Thuja standishii was confirmed by X-ray crystallographic analyses of 1 and its p-bromobenzoate derivative. Aromatase inhibitory activities of standishinal, eight known diterpenes, totarol, 12-methoxyabieta-8,11,13-trien-11-ol, 12-hydroxy-6,7-seco-abieta-8,11,13-triene-6,7-dial, trans-communic acid, labda-8(17),13-dien-12 R,15-olid-19-oic acid, 12 S-hydroxylabda-8(17),13(16),14-trien-19-oic acid, 13-oxo-15,16-dinorlabda-8(17),11 E-dien-19-oic acid and 14-oxo-15-norlabda-8 (17),12 E-dien-19-oic acid from the plant, and four synthetic analogs were evaluated using a recombinant human aromatase. Among them, standishinal and its diacetate derivative had significant inhibitory activities.

Abietanes↗

Potential antitumor promoting diterpenoids from the stem bark of Thuja standishii.

Six diterpenes, including one new natural product, were isolated from a CHCl 3 extract of the stem bark of Thuja standishii. The new compound has been characterized as 15-oxolabda-8(17),13 Z-dien-19-oic acid. The known compounds were identified as ferruginol (2), sugiol (3), isocupressic acid (4), sandaracopimaric acid (5) and 15-oxolabda-8(17),13 E-dien-19-oic acid (6). Compounds 2-5 and the derivatives 4a and 4b were tested for their inhibitory effects on Epstein-Barr virus early antigen (EBV-EA) activation induced by 12-O-tetradecanoylphorbol 13-acetate (TPA). Compounds 2, 3, 4 and 5 showed strong inhibitory effect on EBV-EA induction (100 % inhibition at 1000 mol ratio/TPA).

Antineoplastic Agents, Phytogenic↗

Linking deer browsing and terpene production among genetic identities in Chamaecyparis nootkatensis and Thuja plicata (Cupressaceae).

To investigate whether differential herbivore browsing reflects genetic variation in plant defense expression, variation in needle terpenes and damage caused by black-tailed deer (Odocoileus hemionus) was analyzed on yellow-cedar (Chamaecyparis nootkatensis) and western redcedar (Thuja plicata). In a 100-genet yellow-cedar population, three genets that were heavily browsed and had extremely low levels of monoterpenes (0-0.36% dry matter), sesquiterpenes, and diterpenes were compared to unbrowsed genets (0.85-3.83% monoterpenes in dry matter). These differences were maintained in individuals protected from browsing, suggesting genetically based variation in constitutive terpene production. In western redcedar, heavily browsed trees had significantly lower total monoterpene concentrations (1.69% dry matter) than lightly browsed trees (3.32% dry matter). One heavily browsed tree expressed no monoterpenes. No differences were found for diterpenes. In both species, the genotypes with extremely low monoterpene concentrations came from the same open-pollinated families.

Animals↗

Somatic mutations at microsatellite loci in western Redcedar (Thuja plicata: Cupressaceae).

A per-generation somatic mutation rate for microsatellites was estimated in western redcedar (Thuja plicata, Donn ex D. Don.: Cupressaceae). A total of 80 trees representative of the average size and age of reproductive trees were sampled in four natural populations in southwestern British Columbia. Samples of bulked haploid megagametophytes were collected from two or three positions on each tree, assuming that the collections were far enough apart that the same mutant sector was not sampled twice. All samples were genotyped at eight microsatellite loci. A single mutation corresponding to a stepwise increase in one dinucleotide repeat was detected. The estimated mutation rate for microsatellites was 6.3 x 10(-4) mutations per locus per generation (or 3.1 x 10(-4) per allele per generation), with a 95% confidence interval of 3.0 x 10(-5) to 4.0 x 10(-3) mutations per locus. Somatic mutations can contribute to a greater mutational load in trees, as compared to shorter lived plants, and genotypic mosaics within an individual have important implications for plant defense strategies and plant evolution.

Alleles↗

Responses of transpiration and photosynthesis to reversible changes in photosynthetic foliage area in western red cedar (Thuja plicata) seedlings.

Experiments were conducted on 1-year-old western red cedar (Thuja plicata Donn.) seedlings to determine the response of illuminated foliage to reversible changes in total photosynthetic foliage area (L(A)). Reductions in L(A) were brought about by either shading the lower foliage or by reducing the ambient CO2 concentration (c(a)) of the air surrounding the lower part of the seedling. In the latter case, the vapor pressure was also changed so that transpiration rates (E) could be manipulated independently of photosynthetic rates (A). We hypothesized that following such treatments, short-term compensatory changes would occur in stomatal conductance (g(s)) and A of the remaining foliage. These changes would occur in response to hydraulic signals generated by changes in the water potential gradient rather than changes in the distribution of sources and sinks of carbon within the seedling. When a portion of the foliage was shaded, there was an immediate reduction in whole-seedling E and a concomitant increase in g(s), A and E in the remaining illuminated foliage. However, the intercellular CO2 concentration did not change. These compensatory effects were fully reversed after the shade was removed. When the lower foliage A was reduced to < 0 micromol m-2 s-1, by shading or lowering c(a), and E was either unchanged or increased (by adjusting the vapor pressure deficit), there was no significant increase in g(s) and A in the remaining foliage. We conclude that compensatory responses in illuminated foliage occur only when reductions in L(A) are accompanied by a reduction in whole-plant E. The relationship between the reduction in whole-seedling E and the increase in A is highly linear (r2 = 0.68) and confirms our hypothesis of the strong regulation of g(s) by hydraulic signals generated within the seedling. We suggest that the mechanism of the compensatory effects is a combination of both increased CO2 supply, resulting from increased g(s), and a response of the rate of carboxylation, possibly related to the activity of Rubisco.

Carbon Dioxide↗

Leaf longevity of western red cedar (Thuja plicata) increases with depth in the canopy.

Leaf longevity determines the annual cost of replacing foliage biomass and influences water and nutrient budgets. Longevity is readily estimated in most evergreen species by annual bud scars along the shoot. However, some species with indeterminate growth do not show these annual markers, making estimation of longevity difficult. One of these species is the widespread and economically valuable western red cedar (Thuja plicata J. Donn ex D. Don), for which no dependable estimates of leaf longevity exist. In this study, we estimated leaf longevity for western red cedar by counting growth rings in shoots at the point of leaf abscission. Estimates were obtained on 26 dominant or codominant trees growing in natural stands in a montane forest in northern Idaho, USA. Leaf longevity averaged 8.9 (SE = 0.2) years, but it strongly increased with depth in the canopy (0.3 year m(-1); mean crown depth was 15 m), increasing from a mean of 6.8 years in the upper third of the canopy to 10.6 years in the lower third. The increase in longevity with depth in the crown is consistent with many reports showing that longevity increases in resource-limiting environments. Longevity did not vary significantly with altitude or solar insolation in these montane forests. Among stand-level variables, longevity was correlated only with leaf area index: it increased slightly in stands with high leaf area indices. This approach to longevity estimation may be useful for any species that produces annual rings but no obvious bud scars, including many Cupressaceae species.

Altitude↗

Volatile constituents of the fruit and leaf oils of Thuja orientalis L. grown in Iran.

The composition of the hydrodistilled essential oils from the fruits and leaves of Thuja orientalis L. grown in Iran was analyzed by GC/MS. Nineteen and twenty-eight compounds have been identified in the volatile oils of the fruit and leaf, respectively. While the fruit oil contained alpha-pinene (52.4%), delta-3-carene (14.2%), alpha-cedrol (6.5%) and beta-phellandrene (5.1%), the leaf oil contained alpha-pinene (21.9%), alpha-cedrol (20.3%), delta-3-carene (10.5%) and limonen (7.2%) as the main components.

Gas Chromatography-Mass Spectrometry↗