Clinical features of 31 patients with systemic contact dermatitis due to the ingestion of Rhus (lacquer)

Systemic Contact Dermatitis: The Routes of Allergen Entry

Systemic contact dermatitis (SCD) is a generalized reactivation of type IV hypersensitivity skin diseases in individuals with previous sensitization after a contact allergen is administered systemically. Patients with SCD may consider their dermatitis unpredictable and recalcitrant since the causative allergens are difficult to find. If a patient has a pattern of dermatitis suggestive of SCD but fails to improve with conventional treatment, SCD should be taken into consideration. If doctors are not familiar with the presentations of SCD and the possible routes of allergen sensitization and exposure, the diagnosis of SCD may be delayed. In this work, we summarized all of the routes through which allergens can enter the body and cause SCD, including oral intake, local contact (through skin, inhalation, nasal spray and anal application), implants, and other iatrogenic or invasive routes (intravenous, intramuscular, intraarticular, and intravesicular). This will provide a comprehensive reference for the clinicians to identify the culprit of SCD.

Biological and toxicological evaluation of Rhus trilobata Nutt. (Anacardiaceae) used traditionally in mexico against cancer

Background

Rhus trilobata Nutt. (Anacardiaceae) (RHTR) is a plant of Mexico that is traditionally used as an alternative treatment for several types of cancer. However, the phytochemical composition and potential toxicity of this plant have not been evaluated to support its therapeutic use. Therefore, this study aimed to evaluate the biological activity of RHTR against colorectal adenocarcinoma cells, determine its possible acute toxicity, and analyze its phytochemical composition.

Methods

The traditional preparation was performed by decoction of stems in distilled water (aqueous extract, AE), and flavonoids were concentrated with C₁₈-cartridges and ethyl acetate (flavonoid fraction, FF). The biological activity was evaluated by MTT viability curves and the TUNEL assay in colorectal adenocarcinoma (CACO-2), ovarian epithelium (CHO-K1) and lung/bronchus epithelium (BEAS-2B) cells. The toxicological effect was determined in female BALB/c mice after 24 h and 14 days of intraperitoneal administration of 200 mg/kg AE and FF, respectively. Later, the animals were sacrificed for histopathological observation of organs and sera obtained by retro-orbital bleeding for biochemical marker analysis. Finally, the phytochemical characterization of AE and FF was conducted by UPLC-MS^E.

Results

In the MTT assays, AE and FF at 5 and 18 μg/mL decreased the viability of CACO-2 cells compared with cells treated with vehicle or normal cells (p ≤ 0.05, ANOVA), with changes in cell morphology and the induction of apoptosis. Anatomical and histological analysis of organs did not reveal important pathological lesions at the time of assessment. Additionally, biochemical markers remained normal and showed no differences from those of the control group after 24 h and 14 days of treatment (p ≤ 0.05, ANOVA). Finally, UPLC-MS^E analysis revealed 173 compounds in AE-RHTR, primarily flavonoids, fatty acids and phenolic acids. The most abundant compounds in AE and FF were quercetin and myricetin derivates (glycosides), methyl gallate, epigallocatechin-3-cinnamate, β-PGG, fisetin and margaric acid, which might be related to the anticancer properties of RHTR.

Conclusion

RHTR exhibits biological activity against cancer cells and does not present adverse toxicological effects during its in vivo administration, supporting its traditional use.

Electronic supplementary material

The online version of this article (10.1186/s12906-019-2566-9) contains supplementary material, which is available to authorized users.

Extract of Rhus verniciflua Stokes Induces p53-Mediated Apoptosis in MCF-7 Breast Cancer Cells

Rhus verniciflua Stokes has long been used as a food supplement and traditional herbal medicine for various ailments in East Asia. We evaluated the anticancer effects of Rhus verniciflua Stokes extract (RVSE) on MCF-7 cells by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, flow cytometry, annexin V/7-AAD staining, and western blotting. In addition, the gallic acid content of RVSE was assayed using high-performance liquid chromatography. RVSE inhibited the growth of MCF-7 cells in a dose-dependent manner by inducing apoptosis in the sub-G1 phase. RVSE also significantly increased the number of apoptotic cells and increased the expression of p53 and p21 in a dose-dependent manner. Furthermore, RVSE treatment increased the Bax:Bcl-2 ratio and the levels of apoptosis-related factors, such as cleaved caspase-3 and -9 and PARP, in MCF-7 cells. Our findings suggest that the proapoptotic effect of RVSE on MCF-7 cells is mediated by p53, p21, and the intrinsic mitochondrial cascade. Thus, RVSE shows promise for the prevention and treatment of breast cancer.

Protective effect of Rhus verniciflua Stokes extract in an experimental model of post-menopausal osteoporosis

Post-menopausal osteoporosis (PMO) is a major global human health concern. Owing to the need for therapeutic drugs without side effects, natural extracts containing various polyphenolic compounds that may exert estrogenic effects have been studied in depth. Rhus verniciflua Stokes (RVS), which has been used as a traditional herbal medicine for centuries in Korea, was recently revealed to exert estrogenic effects attributable to its bioactive ingredients sulfuretin and butein, which have strong estrogen receptor–binding affinities. In this study, the protective potential of RVS in PMO was evaluated by using an experimental animal model of PMO, which was established by ovariectomy (OVX) of female Sprague Dawley rats. The oral administration of RVS at 20 mg/kg or 100 mg/kg for 8 weeks markedly protected against OVX-induced atrophy of the uterine tube and reversed the elevation in the ratio of serum receptor activator of nuclear factor-κB ligand to osteoprotegerin, which is a marker of disease severity. In addition, RVS inhibited OVX-induced tibia bone loss, activated osteogenic activity, and suppressed osteoclastic activity in the tibial epiphyseal plate, a region of bone remodeling. Collectively, these factors indicated that the oral intake of RVS might be beneficial for the prevention of PMO.

Eosinophilic gastroenteritis due to rhus ingestion presenting with gastrointestinal hemorrhage

Rhus-related illnesses in Korea are mostly caused by ingestion of parts of the Rhus tree. Contact dermatitis occurrence after ingestion of Rhus-related food is very common in Korea. However, Rhus-related gastrointestinal disease is very rare. Herein, we present a case of eosinophilic gastroenteritis caused by Rhus ingestion. A 75-year-old woman was admitted with hematemesis and hematochezia after Rhus extract ingestion. Routine laboratory tests revealed leukocytosis without eosinophilia. Endoscopy showed friable and granular mucosal changes with touch bleeding in the second portion of the duodenum. Abdominal computed tomography revealed edematous wall thickening of the duodenum and proximal jejunal loops. Patch testing with Rhus extracts showed a strong positive reaction, suggesting Rhus as the allergen. Her symptoms improved after avoidance of the allergen.

Systemic contact dermatitis to foods: nickel, BOP, and more

Systemic contact dermatitis (SCD), a cutaneous reaction that is a direct manifestation of systemic exposure to a known allergen in a sensitized individual, has been increasingly recognized as a cause of persistent cutaneous contact dermatitis that is refractory to conventional therapies. While SCD in response to drugs has been described well in the literature, SCD to allergens in common foodstuffs is a less well-articulated phenomenon. Several foods that are universally consumed throughout the world contain potent allergens including nickel, balsam of Peru, trace metals, urushiol, and sesquiterpene lactones as well as a host of others that may cause a distinctive clinical picture. In this review article, the authors review the typical presentation and prevalence of SCD to foods, pathophysiology, the most common offensive ingestible food allergens, several appropriate diets, and effectiveness of dietary avoidance for situations in which SCD is suspected.

Inhibition of Human Cytochrome P450 Enzymes by Allergen Removed Rhus verniciflua Stoke Standardized Extract and Constituents

Objective. Potential interactions between herbal extracts and the cytochrome P450 (CYP) system lead to serious adverse events or decreased drug efficacy. Rhus verniciflua stoke (RVS) and its constituents have been reported to have various pharmacological properties. We evaluated the inhibitory potential of RVS and its constituents on the major CYP isoforms. Methods. The effects of allergen removed RVS (aRVS) standardized extract and major components, fustin and fisetin isolated from aRVS, were evaluated on CYP1A2, CYP2C9, CYP2C19, CYP2D6, and CYP3A4 isoenzyme activity by a luminescent CYP recombinant human enzyme assay. Results. The aRVS extract showed relative potent inhibitory effects on the CYP2C9 (IC50, <0.001 μg/mL), CYP2C19 (IC50, 9.68 μg/mL), and CYP1A2 (IC50, 10.0 μg/mL). However, it showed weak inhibition on CYP3A4 and CYP2D6. Fustin showed moderate inhibitory effects on the CYP2C19 (IC50, 64.3 μg/mL) and weak inhibition of the other CYP isoforms similar to aRVS. Fisetin showed potent inhibitory effects on CYP2C9, CYP2C19, and CYP1A2. Fisetin showed moderate inhibition of CYP2D6 and weak inhibition of CYP3A4. Conclusions. These results indicate that aRVS, a clinically available herbal medicine, could contribute to herb-drug interactions when orally coadministered with drugs metabolized by CYP2C9, CYP2C19, and CYP1A2.

Impact of Standardized Allergen-Removed Rhus verniciflua Stokes Extract on Advanced Adenocarcinoma of the Ampulla of Vater: A Case Series

Background. Adenocarcinoma of the ampulla of Vater (AAV) is a rare malignancy that has a better prognosis than other periampullary cancers. However, the standard treatment for patients with relapsed or metastatic AAV has not been established. We investigated the clinical feasibility of standardized allergen-removed Rhus verniciflua stokes (aRVS) extract for advanced or metastatic AAV. Patients and Methods. From July 2006 to April 2011, we retrospectively reviewed all patients with advanced AAV treated with aRVS extract alone. After applying inclusion/exclusion criteria, 12 patients were eligible for the final analysis. We assessed the progression-free survival (PFS) and overall survival (OS) of these patients during the follow-up period. Results. The median aRVS administration period was 147.0 days (range: 72–601 days). The best tumor responses according to Response Evaluation Criteria in Solid Tumors were as follows: two with complete response, two with stable disease, and eight with progressive disease. The median OS was 15.1 months (range: 4.9–25.1 months), and the median PFS was 3.0 months (range: 1.6–11.4 months). Adverse reactions to the aRVS treatment were mostly mild and self-limiting. Conclusions. Prolonged survival was observed in patients with advanced AAV under the treatment of standardized aRVS extract without significant adverse effects.

Clinical Features of Systemic Contact Dermatitis Due to the Ingestion of Lacquer in the Province of Chungcheongnam-do

Background

Lacquer contains an allergen, which can cause severe contact dermatitis. Systemic dermatitis resulting from the ingestion of lacquer is quite common in Korea, until now.

Objective

The purpose of this study is to elucidate the clinical features and laboratory findings of systemic contact dermatitis (SCD), due to the ingestion of lacquer in Chungcheongnam-do.

Methods

We retrospectively reviewed the medical records of 33 patients with SCD, after ingestion of lacquer from Soonchunhyang University Hospital in Cheonan, over a 6-month period.

Results

In this study, 33.3% of patients ate lacquer, as a health food, and some (15.2%) by encouragement of friends or spouse. The most common way of ingestion was the lacquer-boiled chicken (48.5%), but many also ate lacquer tree sprouts (42.4%). The skin lesions developed as erythematous maculopapular eruptions, erythema multiforme, erythroderma, purpura, wheals and vesicles. On laboratory findings, 13 patients (52%) exhibited leukocytosis and 11 patients had elevated eosinophil counts.

Conclusion

The general public is becoming more aware of the toxic effects of lacquer ingestion, but still does not fully understand the dangers of lacquer tree sprouts, and this ignorance is frequently causing SCD in Chungcheongnam-do.

Systemic contact dermatitis

Systemic contact dermatitis is an inflammatory skin disease that may occur in persons with contact allergy when they are exposed to the hapten orally, transcutaneously, per rectum, intravesically, intravenously, or by inhalation. The most common causes of systemic contact dermatitis are drugs used both topically and systemically. Other causes are ubiquitously occurring haptens, such as the metals nickel, cobalt, gold, and chromate, and aromatic substances such as spices. Avoidance of the offending hapten is the most obvious treatment. For some haptens, such as nickel, diet treatment may be effective. Chelation therapy with disulfiram is another therapeutic option in nickel-allergic patients with systemic contact dermatitis. Hyposensitization therapy has been attempted with some success in systemic contact dermatitis caused by nickel and Parthenium hysterophorus.

Recent advances in research on lacquer allergy

Allergic contact dermatitis caused by contact with lacquer sap and lacquerware affects the welfare of lacquer workers and the lacquerware industry. Many studies of the mechanism of urushiol allergy, including animal models, have been carried out and have established several hypotheses. In order to provide a comprehensive understanding of lacquer allergy, we review recent advances in the research on lacquer allergy including the chemical properties of lacquer lipid components, allergic mechanism analyses, immunological explanations, allergy medications, and the prevention combined with the research results from our laboratory.

Efficacy and safety of standardized allergen-removed Rhus verniciflua Stokes extract in patients with advanced or metastatic pancreatic cancer: a Korean single-center experience

BACKGROUND

Pancreatic cancer has the worst prognosis because of poor response to conventional therapy. We investigated the clinical feasibility of the standardized allergen-removed Rhus verniciflua Stokes (aRVS) extract as a potential therapeutic agent for advanced or metastatic pancreatic cancer.

PATIENTS AND METHODS

From July 2006 to June 2010, patients with advanced or metastatic pancreatic adenocarcinoma were checked in our institution. After applying inclusion/exclusion criteria, 42 patients were eligible for the final analysis. Overall survival, clinical benefit and adverse events of these patients treated with aRVS in the aftercare period were determined.

RESULTS

In May 2011, 39 patients had died and the remaining 3 patients were alive with evidence of disease. The mean RVS administration period was 3.86 months (95% confidence interval 2.52-5.20). The median overall survival for the entire population was 7.87 months (95% confidence interval 5.14-10.59), and the 1-year survival rate was 26.2%, which is compatible with external controls. Using univariate and multivariate analyses, aRVS treatment including performance status and prognostic index significantly affected overall survival. A clinical benefit response was also shown by aRVS treatment which was not dependent on concurrent chemotherapy. Adverse reactions to aRVS treatment were mostly mild and self-limiting.

CONCLUSIONS

The standardized aRVS extract might be beneficial for patients with advanced or metastatic pancreatic cancer since it positively affected overall survival and clinical symptoms without significant adverse effects.

Rhus verniciflua stokes against advanced cancer: a perspective from the Korean Integrative Cancer Center

Active anticancer molecules have been searched from natural products; many drugs were developed from either natural products or their derivatives following the conventional pharmaceutical paradigm of drug discovery. However, the advances in the knowledge of cancer biology have led to personalized medicine using molecular-targeted agents which create new paradigm. Clinical benefit is dependent on individual biomarker and overall survival is prolonged through cytostatic rather than cytotoxic effects to cancer cell. Therefore, a different approach is needed from the single lead compound screening model based on cytotoxicity. In our experience, the Rhus verniciflua stoke (RVS) extract traditionally used for cancer treatment is beneficial to some advanced cancer patients though it is herbal extract not single compound, and low cytotoxic in vitro. The standardized RVS extract's action mechanisms as well as clinical outcomes are reviewed here. We hope that these preliminary results would stimulate different investigation in natural products from conventional chemicals.

Leaf extract of Rhus verniciflua Stokes protects dopaminergic neuronal cells in a rotenone model of Parkinson's disease

Objectives

The present study investigated the neuroprotective effects of Rhus verniciflua Stokes (RVS) leaf extract on rotenone-induced apoptosis in human dopaminergic cells, SH-SY5Y.

Methods

Cells were pretreated with RVS extract for 1 h then treated with vehicle or rotenone for 24 h. Cell viability, cell cytotoxicity, cell morphology and nuclear morphology were examined by MTT assay, lactate dehydrogenase release assay, phase contrast microscopy and staining with Hoechast 33342, respectively. Reactive oxygen species were measured by 2′7′-dichlorofluorescein diacetate and fragmented DNA was observed by TUNEL assay. Mitochondrial membrane potential was determined by Rhodamine 123. Pro-apoptotic and anti-apoptotic proteins and tyrosine hydroxylase were analysed by Western blotting.

Key findings

Results showed that RVS suppressed rotenone-induced reactive oxygen species generation, cellular injury and apoptotic cell death. RVS also prevented rotenone-mediated changes in Bax/Bcl-2 levels, mitochondrial membrane potential dissipation and Caspase 3 activation. Moreover, RVS pretreatment increased the tyrosine hydroxylase levels in SH-SY5Y cells.

Conclusions

These findings demonstrate that RVS protects SH-SY5Y cells against rotenone-induced injury and suggest that RVS may have potential therapeutic value for neurodegenerative disease associated with oxidative stress.

A systematic approach to systemic contact dermatitis and symmetric drug-related intertriginous and flexural exanthema (SDRIFE): a closer look at these conditions and an approach to intertriginous eruptions

Systemic contact dermatitis is a condition that occurs when an individual sensitized to a contact allergen is exposed to that same allergen or a cross-reacting molecule through a systemic route. Systemic exposure to allergens can include transcutaneous, transmucosal, oral, intravenous, intramuscular, and inhalational routes. Baboon syndrome is perhaps the most recognizable form of systemic contact dermatitis, presenting with diffuse, well demarcated erythema of the buttocks, upper inner thighs, and axillae. Other forms of systemic contact dermatitis include dermatitis at sites of previous exposure to the allergen such as at a previous site of dermatitis or at sites of previous positive patch tests, dyshidrotic hand eczema, flexural dermatitis, exanthematous rash, erythroderma, and vasculitis-like lesions. The most common causes of systemic contact dermatitis consist of three groups of allergens: (i) metals including mercury, nickel, and gold; (ii) medications including aminoglycoside antibacterials, corticosteroids, and aminophylline; and (iii) plants and herbal products including the Compositae and Anacardiaceae plant families and Balsam of Peru. Baboon syndrome caused by systemic medications without a known history of previous cutaneous sensitization in the patient has been termed drug-related baboon syndrome (DRBS) or symmetric drug-related intertriginous and flexural exanthema (SDRIFE). Criteria for SDRIFE include exposure to systemic drug at first or repeated dose, erythema of the gluteal/perianal area and/or V-shaped erythema of the inguinal area, involvement of at least one other intertriginous localization, symmetry of affected areas, and absence of systemic toxicity. The most common causes are aminopenicillins, β-lactam antibacterials, and certain chemotherapeutic agents, though the list of etiologic agents continues to grow. Baboon syndrome and SDRIFE should be strongly considered in a patient presenting with a symmetric intertriginous eruption involving multiple body folds. With the knowledge of the most frequent causes of these conditions, a detailed history and review of exposures will guide the clinician in the search for the most likely etiologic agent.

A case of recurred hepatocellular carcinoma refractory to doxorubicin after liver transplantation showing response to herbal medicine product, Rhus verniciflua Stokes extract

There is no established protocol proven to be beneficial for treatment of hepatocellular carcinoma recurrence after liver transplantation. Only a few reports have shown direct treatment by surgery or ablation to be independent predictors of survival for localized recurrence. Moreover, the necessity of immunosuppression to prevent allograft rejection makes many physicians hesitate to administer systemic chemotherapy. This case report documents a case in which the administration of an herbal product, an extract of the lacquer tree, Rhus verniciflua Stokes, was associated with a decrease in the size of lung metastases in a patient with recurrent hepatocellular carcinoma after liver transplantation refractory to doxorubicin. This patient experienced prolonged survival compared with average survival times and little toxicity.

Polymerized urushiol of the commercially available rhus product in Korea

BACKGROUND

Systemic contact dermatitis commonly occurs with the intake of rhus (boiled chicken with rhus) as a health food and a folk medicine to cure gastrointestinal diseases in Korea. Rhus companies insist they have the technology for rhus detoxification. However, the numbers of systemic allergic contact dermatitis patients, caused by rhus, have not decreased. The principle of present techniques for rhus detoxification is the induction of the polymerization of urushiol, but polymerized urushiol may still have antigenicity, although to a diminished degree. The Korean Food and Drug Administration (KFDA) has a regulation to control urushiol use as a food. However, the laboratory method that KFDA uses for detection of rhus can only detect the urushiol monomer.

OBJECTIVE

We conducted experiments to detect polymerized urushiol in rhus products, which were considered not to include urushiol by the KFDA.

METHODS

Rhus product approved by the KFDA was separated with chloroform. The chloroform fractionation was accomplished on a recycle HPLC system. Four peaks were achieved and evaporated to give an amorphous powder. Each powder was analyzed on a NMR system and mass spectrometer.

RESULTS

The material considered to be urushiol dimer, with a 638 molecular weight (MW), was detected in one of the four powders as per the HPLC peaks.

CONCLUSION

We concluded that commercially available rhus product is comprised of material considered to be urushiol dimer. Therefore, even if the antigenicity of the rhus products is low, this product may cause adverse effects and is not completely detoxified.

Clinical patterns of phytodermatitis

Exposure to plants is very common, through leisure or professional activity. In addition, plant products and botanic extracts are increasingly present in the environment. Cutaneous adverse reactions to plants and their derivatives occur fairly frequently, and establishing the correct diagnosis is not always easy. The astute clinician relies on a detailed history and a careful skin examination to substantiate his opinion. This article reviews the characteristic clinical patterns of phyto- and phytophotodermatitis and some less common presentations.

Acute Generalized Exanthematous Pustulosisafter Ingestion of Lacquer Chicken

Acute generalized exanthematous pustulosis (AGEP) is an acute pustular eruption characterized by multiple small, sterile, non-follicular pustules on an erythematous and edematous base, usually accompanied by fever and neutrophilia. It is attributed to systemic drugs in over 90% of cases, mainly β-lactam and macrolide antimicrobials. Viral infections, mercury exposure, Ginkgo biloba, and spider bites may occasionally cause the condition. We report a rare case of AGEP induced by intake of lacquer chicken in a 40-year-old man.

Plant poisoning

Each year over 100,000 exposures to toxic plants are reported to poison centers throughout the United States. Most of these exposures are of minimal toxicity largely because of the fact that they involve pediatric ingestions, which are of low quantity. The more serious poisonings usually involve adults who have either mistaken a plant as edible or have deliberately ingested the plant to derive perceived medicinal or toxic properties. The plants within this manuscript have been chosen because they have been documented to cause fatalities or account for emergency medicine visits. In this discussion, plants are grouped by their toxins rather than on the basis of their taxonomy.

Life-threatening erythroderma: diagnosing and treating the “red man”

Exfoliative erythroderma, or diffuse erythema and scaling of the skin, may be the morphologic presentation of a variety of cutaneous and systemic diseases. Establishing the diagnosis of the underlying disease is often difficult and, not uncommonly, erythroderma is classified as idiopathic. Several cases are presented to demonstrate the diversity of presentation of this disease. Laboratory findings are typically unhelpful in establishing the etiology of erythroderma. Clinical data combined with multiple skin biopsies over time are necessary. Systemic complications of erythroderma include infection, fluid and electrolyte imbalances, thermoregulatory disturbance, high output cardiac failure, and acute respiratory distress syndrome. The initial approach to the management of erythroderma of any etiology includes attention to nutrition, fluid and electrolyte replacement, and the institution of gentle local skin care measures. Oatmeal baths and wet dressings to weeping or crusted sites should be followed by application of bland emollients and low-potency topical corticosteroids. Systemic dermatologic therapy may be required to maintain improvement achieved with local measures or to control erythroderma refractory to local measures. The prognosis of erythroderma is dependent on the underlying etiology.

Poison ivy: An underreported cause of erythema multiforme

The relationship between herpes simplex virus (HSV) and erythema multiforme (EM) has been well described. Many authors contend that EM (excluding Stevens-Johnson syndrome and toxic epidermal necrolysis) occurs almost exclusively as a response to HSV infection. During the past year, however, we have observed several cases of EM complicating severe Rhus allergic contact dermatitis. Although this association has been previously documented, the paucity of cases in the literature, along with our experience, suggests that this is an underreported phenomenon. We describe 4 of our cases.

Extract of Toxicodendron quercifolium caused genotoxicity and antigenotoxicity in bone marrow cells of CD1 mice

As has been shown in numerous studies, naturally occurring compounds can have protective effects towards mutagens and carcinogens. In the present study, the genotoxic/antigenotoxic effect of Toxicodendron quercifolium (poison ivy) extract, which has been identified as antigenotoxic in human HepG2 cells in former studies, was examined in the in vivo micronucleus assay using polychromatic erythrocytes (PCE) of bone marrow of CD1-mice. For this, D0 (1:10), D0 (1:25), D0 (1:50), D1 (1:50), D2 (1:50), and D4 (1:50) dilutions of ethanolic plant extract prepared on the basis of the "Hömoopathisches Arzneimittelbuch (HAB 2000)" were administered orally to CD1 mice over a period of two days. A significant increase (p < 0.05) in micronucleus frequencies was found after administration of D0 (1:10), the highest tolerated dose. Additionally, antigenotoxic effects of T. quercifolium towards benzo(a)pyrene-induced micronucleus formation were studied. For that, four dilutions of the plant extract [D0, D2, D4, D6, each 1:50] were administered orally to CD1 mice for five days prior to the administration of benzo(a)pyrene (250 mg/kg b.w.) for another two days. It was found that the administration of the dilutions D0 (1:50) and D2 (1:50) of T. quercifolium extract significantly inhibited benzo(a)pyrene-induced micronucleus formation (p < 0.0001). The results of this study indicated that T. quercifolium extract has the character of a so-called "Janus"-genotoxin: High doses led to a weak but significant increase of micronucleus frequencies whereas low doses showed chemopreventive effects towards benzo(a)pyrene-induced DNA damage. The constituents of T. quercifolium responsible for the genotoxic and antigenotoxic effects may be flavonoids, which are known to have prooxidative and scavenging effects and identified by HPLC-MS/MS.

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.