Studies on laccases of lacquer trees. I. Comparison of laccases obtained from Rhus vernicifera and Rhus succedanea.
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Humans↗
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Studies on the biological activity of Rhus striata. 3. Toxicity vs. hypersensitivity of dermal reactions in guinea pigs to Rhus striata ("manzanillo") extracts.
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Animals↗
[Decline of violence in ]rhus. Violence registered in ]rhus hospital during a period of 12 years].
The aim of this study was to describe the changes in frequency and character of interpersonal violence in Aarhus during a twelve year period. A one year (1993-1994) prospective registration of all persons exposed to violence and attending the casualty wards or the Department of Forensic Medicine was performed. The results were compared with similar studies performed in 1981-1982 and 1987-1988. The incidence in the last one year period had decreased significantly to 5.5 cases/1000 inhabitants compared to 6.5 in 1981-1982 and 7.5 in 1987-1988. The decrease was most distinct among men between 15-24 years of age. Ninety percent of the lesions were minor and the severity did not differ from the former study. Among risk factors associated to severe violence were men between 25-49 years of age, foreigners, use of knives and domestic violence. Firearms were only involved in 0.8% of the cases. Significantly higher proportion of the victims reported the incidence to the police in 1993-1994 than previously.
Adult↗
Clinical features of 31 patients with systemic contact dermatitis due to the ingestion of Rhus (lacquer).
In Korea, Rhus has been used as a folk medicine to cure gastrointestinal diseases and as a health food. We review the clinicopathological and laboratory findings in patients with systemic contact dermatitis caused by intake of Rhus. We reviewed medical records and histopathological sections from 31 patients during a 10-year period. The male/female ratio was 1.4: 1 and the average age was 43.8 years (range 22-70). Ten patients (32%) had a known history of allergy to lacquer. Rhus was ingested to treat gastrointestinal problems including indigestion and gastritis (45%), and as a health food (39%), in cooked meat, in herbal medicine, or taken by inhalation. The patients developed skin lesions such as a maculopapular eruption (65%), erythema multiforme (EM, 32%), erythroderma (19%), pustules, purpura, weals and blisters. Erythroderma was very frequent in patients with a known history of allergy to lacquer, but maculopapular and EM-type eruptions were more frequently observed in those without a history of allergy. All patients experienced generalized or localized pruritus. Other symptoms included gastrointestinal problems (32%), fever (26%), chills and headache; many developed leucocytosis (70%) with neutrophilia (88%), while some showed toxic effects on liver and kidney. Fifty-nine per cent of patients observed cutaneous or general symptoms within a day after ingestion of Rhus. There was no difference in the time lag for symptoms to develop between patients allergic and not allergic to Rhus. All patients responded well to treatment with systemic steroids and antihistamines. Common histopathological findings were vascular dilatation, perivascular lymphohistiocytic infiltration, and extravasation of red blood cells in the upper dermis. Rhus lacquer should not be ingested in view of its highly allergic and toxic effects.
Administration, Oral↗
Kinetic studies of Rhus vernicifera laccase. Role of the metal centers in electron transfer.
The reactions of Rhus vernicifera (monophenol,dihydroxyphenylalanine: oxygen oxidoreductase, EC 1.14.18.1) with the reducing substrates hydroquinone and ascorbic acid have been investigated with the stopped-flow technique. Rhus laccase appears to be present in two molecular forms with a pH-sensitive equilibrium constant regulating the relative concentrations of each species. A model for the reaction of Rhus laccase with reducing substrates has been formulated. The model is similar to one formulated earlier for the anaerobic reduction of laccase from Polyporus versicolor (Andréasson, L.-E., Malström, B.G., Strömberg, C. and Vänngård, T. (1973) Eur. J. Biochem. 34, 434-439) and accounts for the reduction also of this enzyme. The essentials of the model are as follows: Electrons are taken up from reductants one at a time. The type 1 Cu2+ has a central role in mediating the transfer of at least one of the electrons needed for the reduction of the co-operative two-electron acceptor. Intramolecular reactions determine the concentrations of two molecular forms of the enzyme and influence the rate of reduction of the two-electron acceptor. The model, which has been used for successful simulations of the anaerobic reduction of Rhus laccase, is capable of explaining the reduction of laccases also in the presence of the inhibitor F-. In addition, the model gives an explanation of the behaviour of the laccases when reducing substrates and O2 are simultaneously present and is consistent with earlier observations of the post-steady-state reduction of the type 1 Cu2+ and the two-electron accetor (Holwerda, R.A. and Gray, H.B. (1974) J. Am. Chem. Soc. 96, 6008-6022).
Anaerobiosis↗
Cytokine mRNA expression in human epidermis after patch treatment with rhus and sodium lauryl sulfate.
BACKGROUND: Cytokines have been shown to play a pivotal role in the development and elicitation of contact hypersensitivity reactions. The sources of these cytokines in the skin include T cells, keratinocytes, and Langerhans cells. OBJECTIVE: In an effort to characterize the cytokines involved in the elicitation phase of a contact allergic response, we examined mRNA expression in human epidermis following patch testing with a known allergen and vehicle. METHODS: Allergic subjects were patch tested with poison ivy allergen (rhus), irritant (sodium lauryl sulfate [SLS]) and vehicle controls for 24 hours. Epidermal samples were obtained from the patch sites by a suction blister technique. Total RNA was isolated from the epidermis and the level of cytokine gene expression was determined using reverse transcriptase polymerase chain reaction (RT-PCR). PCR products for the various cytokines were confirmed and semiquantitated by liquid hybridization with (32)P-labeled product-specific probes. RESULTS: Results of liquid hybridization confirmed the presence of message for interleukin (IL)-2, IL-4 and IL-10 in rhus, SLS, and vehicle treated sites. Generally, in rhus treated sites, the steady state level of message for IL-2 was highest, followed by IL-4 and IL-10, in decreasing levels. In contrast, only minimal expression of mRNA for these cytokines was observed in irritant and vehicle treated sites. Interestingly, interferon (IFN)-gamma mRNA was not detected at 24 hours in rhus, SLS, or vehicle treated sites. CONCLUSION: These preliminary results indicate differences in the steady state levels of cytokine mRNA in allergen versus vehicle and irritant treated sites at 24 hours after treatment.
Cytokines↗
Antimutagenic activity of flavonoids from the heartwood of Rhus verniciflua.
Pretreatment of the methanolic extract of the heartwood of Rhus verniciflua (Anacardiaceae) to rats prevented the activation of hepatic microsomal cytochrome p(450) enzymes, inhibition of hepatic glutathione S-transferase by bromobenzene treatment, respectively, and therefore significantly decreased malondialdehyde content in the rat. The Ames test showed that the addition of 1.0 mg/plate of the methanolic extract or the EtOAc fraction of the Rhus verniciflua heartwood extract potentially inhibited the mutagenicity by aflatoxin B(1). Column chromatography of the EtOAc fraction yielded four flavonoids, garbanzol (1), sulfuretin (2), fisetin (3), fustin (4), mollisacasidin (5). When these components were subjected to the Ames test, it was found that sulfuretin might effectively prevent the metabolic activation or scavenge electrophilic intermediates capable of causing mutation. In contrast, fustin showed a dose-independent antimutagenic activity and it has mutagenic/antimutagenic activity. However, a mixture of sulfuretin and fustin (1:1) exhibited dose-dependent antimutagenicity indicating that sulfuretin inhibited the mutagenicity of fustin. These results suggest that the extract of Rhus verniciflua heartwood containing flavonoid complex could be a potent anticarcinogen.
Aflatoxin B1↗
A controlled trial of clobetasol propionate ointment 0.05% in the treatment of experimentally induced Rhus dermatitis.
We studied the effectiveness of clobetasol propionate ointment 0.05% in experimentally induced Rhus dermatitis. Clobetasol rapidly decreased the vesiculation at each treated site, although the effect was most prominent at the site to which clobetasol was applied the earliest, that is, at 12 hours after exposure to Rhus extract. On the basis of this experimental model, clobetasol propionate ointment 0.05% may be effective therapy for naturally occurring Rhus dermatitis.
Adult↗
Comparative morphology and physiology of fruit and seed development in the two shrubs Rhus aromatica and R. glabra (Anacardiaceae).
Morphology and physiology of fruit and seed development were compared in Rhus aromatica and R. glabra (Anacardiaceae), both of which produce drupes with water-impermeable endocarps. Phenology of flowering/fruiting of the two species at the study site was separated by ∼2 mo. However, they were similar in the timetable and pattern of fruit and seed development; it took ∼2 mo and ∼1.5 mo for flowers of Rhus aromatica and R. glabra, respectively, to develop into mature drupes. The single sigmoidal growth curve for increase in fruit size and in dry mass of these two species differs from the double-sigmoidal one described for typical commercial drupes such as peach and plum. Order of attainment of maximum size was fruit and endocarp (same time), seed coat, and embryo. By the time fruits turned red, the embryo had reached full size and become germinable; moisture content of seed plus endocarp had decreased to ∼40%. The endocarp was the last fruit component to reach physiological maturity, which coincided with development of its impermeability and a seed plus endocarp moisture content of <10%. At this time, ∼50, 37, and 13% of the dry mass of the drupe was allocated to the exocarp plus mesocarp unit, endocarp, and seed, respectively. The time course of fruit and seed development in these two species is much faster than that reported for other Anacardiaceae, including Rhus lancea, Protorhus, and Pistacia.
Journal Article↗
Allergic contact dermatitis to Toxicodendron succedaneum (rhus tree): an autumn epidemic.
AIMS: To document all cases of allergic contact dermatitis (phytodermatitis) due to contact with Toxicodendron succedaneum (rhus tree) presenting to a dermatology clinic during 1993. METHOD: Case-note review of all cases of phytodermatitis attributed to exposure to rhus tree seen during 1993 in a dermatology clinic. RESULTS: Twenty cases of phytodermatitis to T succedaneum were reviewed. Eight patients were females and 12 males with a bimodal age distribution (ten children under age of 15 yr, five adults between 35-45 yr of age). Younger patients presented with facial dermatitis reflecting facial contact whilst playing under rhus trees. Older patients presented largely with a dermatitis affecting the upper limbs reflecting contact whilst gardening (usually pruning). Fifteen out of twenty presented during the months of March through May (ie. autumn), with the remainder presenting in summer (Dec-Feb). The majority of patients required systemic steroids to settle the intense dermatitis. CONCLUSIONS: Phytodermatitis to T succedaneum is not uncommon in New Zealand, particularly during the autumn months. The clinical presentation varies according to the patient's activity.
Adolescent↗
Effects of Rhus coriaria L (Anacardiaceae) on lipid peroxidation and free radical scavenging activity.
In order to evaluate the antioxidant potential of Rhus coriaria L. (Anacardiaceae), a well-known spice, the methanolic extract (water-soluble part) was prepared and investigated using free radical-generating systems in vitro. The IC(50) value of the extract for lipid peroxidation was estimated as 1200 microg/mL in the Fe(+2)-ascorbate system while those for superoxide-scavenging activity in the xanthine-xanthine oxidase method and hydroxyl radical scavenging activity in the deoxyribose decomposition method were 282.92 microg/mL and 3850 microg/mL, respectively. These data suggest that the methanolic extracts of Rhus coriaria L. fruits have considerable antioxidant activity against free radicals and lipid peroxidation in vitro, a fact that may encourage in vivo studies.
Animals↗
Clinical and immunologic features of systemic contact dermatitis from ingestion of Rhus (Toxicodendron).
Oral or parenteral exposure to certain contact allergens may elicit an eczematous skin reaction in sensitized individuals. This phenomenon has been called systemic contact dermatitis (SCD) and is relatively rare when compared with classical contact dermatitis. We reviewed and analysed the clinical and immunologic features of 42 patients with SCD caused by ingestion of Rhus (Toxicodendron), 24 males and 18 females, average age 44 years (range 24-72). Several of such patients (33%) had a known history of allergy to lacquer. The patients developed skin lesions such as generalized maculopapular eruptions (50%), erythroderma (29%), vesiculobullous lesions (14%) and erythema multiform (EM)-like lesions (7%). Many patients (57%) developed leucocytosis with neutrophilia (74%). In some patients (5%), abnormalities of liver function developed. We also analysed lymphocyte subsets in the peripheral blood of 12 patients. The lymphocyte subsets studied were T cells (CD3), B cells (CD19), natural killer (NK) cells (CD3-CD16+/CD56+), helper/inducer cells (CD4), cytotoxic/suppressor cells (CD8) and helper/suppressor ratio (CD4/CD8). The lymphocyte subsets of all 12 patients studied were within the normal range. Moreover, there were no differences between patients with a history of allergy to lacquer and those without a history of allergy to lacquer. Therefore, rather than an immunologic response, the skin eruption seems to be caused by a toxic reaction because of Rhus.
Administration, Oral↗
Antirheumatoid arthritis effect of Rhus verniciflua and of the active component, sulfuretin.
Oral administration of the MeOH extract of Rhus verniciflua or of an EtOAc fraction containing an EtOAc-soluble portion of the MeOH extract slightly decreased rheumatoid arthritis (RA) and C-reactive protein (CRP) factors in Freund's complete adjuvant reagent FCA-treated rats, indicating that they are active extracts for rheumatoid arthritis, the EtOAc extract being more active. Treatment with these two extracts prevented histological changes such as synovial cell proliferation, inflammatory cell infiltration and fat necrosis compared with an FCA-treated group. Oral administration (30 mg/kg) of sulfuretin and fustin, which were isolated from the EtOAc extract by activity-guided separation, significantly decreased RA and CRP factors, the former being more active than the latter. Treatment with the EtOAc fraction ( p. o.) containing sulfuretin significantly decreased malondialdehyde (MDA) formation, and highly increased the activities of superoxide dismutase, catalase and glutathione peroxidase. Inhibition of xanthine oxidase and aldehyde oxidase in FCA-treated rats was also evident. Since treatment with sulfuretin and the EtOAc extract decreased the concentration of infiltrated mast cells in the rat knee exhibiting rheumatoid arthritis, we suggest that the Rhus verniciflua extract, which contains sulfuretin as an active component, may prevent rheumatoid syndromes by inhibiting reactive oxygen species.
Administration, Oral↗
Genetic variation and evidence of hybridization in the genus Rhus (Anacardiaceae).
Rhus michauxii, a rare plant species endemic to the southeastern United States, was previously known only from central North Carolina and one site in Georgia. An additional site, which is now believed to represent the largest known concentration of R. michauxii, was recently discovered at Ft. Pickett near Blackstone, Virginia. Morphological characteristics in several of the Ft. Pickett Rhus populations appear to be intermediate between R. michauxii and the widespread R. glabra, a closely related congener that co-occurs at Ft. Pickett. Although morphological evidence of hybridization between R. michauxii and R. glabra in North Carolina has been provided previously, genetic marker data are lacking. In the present study we examined levels of allozyme variation at 11 polymorphic loci within and among seven populations of R. michauxii, one population of R. glabra, and four putative hybrid populations at Ft. Pickett. Overall, R. michauxii had typical levels of within-population genetic variation when compared to other species with similar life-history characteristics. In contrast, the proportion of genetic variation among populations (G(ST)) was considerably lower than expected. Finally, R. michauxii and R. glabra appear to have a fixed allelic difference at the Idh2 locus. This enabled us to confirm hybridization in all four of the putative hybrid populations and one of the R. michauxii populations.
Genetic Variation↗
Ethanol-eluted extract of Rhus verniciflua stokes inhibits cell growth and induces apoptosis in human lymphoma cells.
Rhus verniciflua Stokes (RVS) has been used as a traditional herbal medicine. Several earlier studies indicated that an ethanol extract of RVS has both anti-oxidant and anti-tumor properties, although the mechanism for the activity remains to be elucidated. In this report, we prepared a highly purified ethanol extract from RVS, named REEE-1 (Rhus ethanol eluted extract-1), and investigated the mechanism involved in its growthinhibitory effect on the human B and T lymphoma cell lines, BJAB and Jurkat, respectively. Results from tritium uptake proliferation assays showed that the proliferative capacities of both BJAB and Jurkat cells were strongly suppressed in the presence of REEE-1. This was further confirmed through trypan blue exclusion experiments that revealed a dose-dependent decrease in viable cell numbers after REEE-1 treatment. REEE-1-mediated suppression of cell growth was verified to be apoptotic, based on the increase in DNA fragmentation, low fluorescence intensity in nuclei after propidium iodide staining, and the appearance of DNA laddering. In particular, REEE-1 exerted its anti-oxidant activity through the inhibition of hydroxyl radical-mediated degradation by iron ion chelation rather than direct scavenging of hydroxyl radicals. Furthermore, REEE-1 was revealed to be a potential scavenger of superoxide anions. Collectively, our findings suggest that REEE-1 is a natural anti-oxidant that could be used as a cancer chemo-preventive and therapeutic agent.
Animals↗
Assay of topical corticosteroids. Efficacy of suppression of experimental Rhus dermatitis in humans.
Rhus dermatitis, experimentally induced in humans, was used as a model for determining the efficacy of various proprietary topical steroids. One-centimeter squares of vesicular dermatitis were induced by patch application of Rhus oleoresin. The steroids were then applied without occlusion once daily for four days, with readings of the therapeutic effect taken on the fifth day. Only potent steroids provided unequivocal suppression in this severe test. The rank order of efficacy corresponded to clinical experience. Cream and ointment formulations of the same steroid at the same strength did not differ. High strength preparations were more effective than regular strengths. Relief of pruritus was an important early effect of efficaceous steroids.
Administration, Topical↗
Antimicrobial constituents of Rhus glabra.
The antimicrobial activity of the methanol extract and isolated constituents of Rhus glabra (Anacardiaceae), a species used in folk medicine by North American native people, was evaluated against 11 microorganisms, including gram-positive and gram-negative bacteria. The extract was subsequently fractionated and monitored by bioassays leading to the isolation of three antibacterial compounds, the methyl ester of 3,4,5-trihydroxybenzoic acid (methyl gallate) (minimal inhibition concentration (MIC) 12.5 micrograms/ml), 4-methoxy-3,5-dihydroxybenzoic acid (MIC 25 micrograms/ml) and gallic acid (MIC > 1000 micrograms/ml). The first two compounds are reported here for the first time from Rhus glabra. Their structures were established using spectroscopic and chemical methods.
Anti-Bacterial Agents↗
Galloylglucoses and riccionidin A in Rhus javanica adventitious root cultures.
Adventitious root cultures of Rhus javanica L. produced large amounts of galloylglucoses (gallotannins) and an anthocyanidin, riccionidin A, formerly found only in liverworts. Production of both galloylglucoses and riccionidin A in the adventitious root culture system was suppressed by light. The Rhus root culture showed the highest productivity for those secondary metabolites in a modified Linsmaier-Skoog (LS) liquid medium containing 30 mM NH4+ and 30 mM NO3- as nitrogen sources in the presence of 10(-6) M 3-indoleacetic acid (IAA).
Anthocyanins↗