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Sample records for anthralin

  1. Excited state Intramolecular Proton Transfer in Anthralin

    DEFF Research Database (Denmark)

    Møller, Søren; Andersen, Kristine B.; Spanget-Larsen, Jens;

    1998-01-01

    Quantum chemical calculations performed on anthralin (1,8-dihydroxy-9(10H)-anthracenone) predict the possibility of an excited-state intramolecular proton transfer process. Fluorescence excitation and emission spectra of the compound dissolved in n-hexane at ambient temperature results in an......, associated with an excited-state intramolecular proton transfer process....

  2. An EPR method for estimating activity of antioxidants in mouse skin using an anthralin-derived radical model.

    Science.gov (United States)

    Kawai, Sayo; Matsumoto, Ken-Ichiro; Utsumi, Hideo

    2010-03-01

    Inhibitory effects of intravenously or orally administered antioxidants on the anthralin-derived radical generated in skin (mainly in the epidermis) of living mice by ultraviolet-A (UVA) irradiation were estimated. Anthralin was applied to the dorsal skin of living mice and the mice were then exposed to UVA. The EPR signal intensity in skin tissue strips obtained from mice after anthralin-UVA treatment was measured by an X-band EPR spectrometer. Several common antioxidants such as ascorbate, glutathione and Trolox (a vitamin E analogue) intravenously administered to mice reduced anthralin-derived radical generation. Trolox showed the most prolonged and powerful effect. Intravenous injection of a clinically used cerebral neuroprotective drug, Edarabone (Radicut), also showed depletion for the anthralin-derived radical. Oral administration of a commercialized nutritional supplement (a cocktail of 17 herbals and vitamins) also attenuated the anthralin-derived radical. The anthralin-UVA treatment model for antioxidant activity in the epidermis is a potentially feasible method to estimate activity of antioxidants in the body.

  3. Psoriasis Therapy: A Current Perspective

    OpenAIRE

    Lowe, Nicholas J.

    1983-01-01

    Psoriasis is a common papulosquamous skin disease which frequently presents a therapeutic challenge to physicians. Topical therapy with steroids, coal tars and anthralin are effective when used properly for many patients. More severely affected patients may require phototherapy using coal tars and anthralin plus ultraviolet radiation. Systemic methotrexate administration is indicated for some patients with severe skin and arthropathic psoriasis. Treatment using psoralen and long-wavelength ul...

  4. Intramolecular Hydrogen Bonding in (2-Hydroxybenzoyl)benzoylmethane Enol

    DEFF Research Database (Denmark)

    Hansen, Bjarke Knud Vilster; Winther, Morten; Spanget-Larsen, Jens

    2014-01-01

    In the stable enol tautomer of the title compound (OHDBM), one carbonyl group is flanked by two β-hydroxy groups, giving rise to bifold intramolecular H-bonding. A similar situation is found in other β,β'-dihydroxy carbonyl compounds like chrysazin, anthralin, 2,2'-dihydroxybenzophenone, and the ......In the stable enol tautomer of the title compound (OHDBM), one carbonyl group is flanked by two β-hydroxy groups, giving rise to bifold intramolecular H-bonding. A similar situation is found in other β,β'-dihydroxy carbonyl compounds like chrysazin, anthralin, 2,2'-dihydroxybenzophenone......, and the dienol form of 1,3-dibenzoylacetone. But in these examples the two H-bonds are equivalent, while in the case of OHDBM they are chemically different, involving one enolic and one phenolic hydroxy group. OHDBM is thus an interesting model compound with two competing H-bonds to the same carbonyl group...

  5. In search for new antipsoriatic agents: NAD topical composition.

    Science.gov (United States)

    Wozniacka, A; Szajerski, P; Adamus, J; Gebicki, J; Sysa-Jedrzejowska, A

    2007-01-01

    The aim of the study was to examine the effectiveness of the oxidized form of nicotinamide adenine dinucleotide (NAD(+)), adenosine precursor, in 37 patients suffering from psoriasis. As NAD(+) is known to be relatively unstable, the second goal was to establish the proper conditions for the satisfactory stability of topical NAD(+) composition. In each patient, two matching plaques were selected for the study. Topical treatment with 1 or 0.3% NAD(+) in Vaseline ointment administered twice daily was compared with overnight therapy with 0.1% anthralin applied for 12 h and placebo. The enzymatic method was applied to determine the stability of NAD(+) in Vaseline ointment. After a 4-week application, the reduction in erythema, infiltration and desquamation caused by 1 or 0.3% topical NAD(+) composition was similar to the reduction caused by 0.1% anthralin. It was demonstrated that NAD(+) underwent a considerable decomposition at room temperature, while it was sufficiently stable at 5 degrees C; thus, for a longer use the agent should be stored at fridge temperature. NAD(+) therapy combines good efficacy, cosmetic acceptability and convenient twice-daily application. PMID:17035720

  6. COMPARISON OF EFFICACY OF VARIOUS TOPICAL TREATMENT MODALITIES IN ALOPECIA AREATA

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    Ashok

    2015-02-01

    Full Text Available BACKGROUND: Alopecia areata is one of the common causes of localized hair loss. Alopecia areata can have spontaneous remission or can follow unpredictable course with exacerbation. Due to which it can be a cause of cosmetic concern for the patient. AIM: To know the efficacy of various topical treatment modalities in Alopecia areata. METHODS: 100 patients presenting with alopecia areata to the dermatology outpatient department of Basaveshwar Teaching and General Hospital and Sangameshwar Hospital, Gulbarga, were included in this study. It was conducted as a randomized prospective study for a period of 12 weeks after taking an informed consent from the patient. Patients were randomly distributed into four treatment groups – A, B, C, D. Group. A were treated with 0.05% Betamethasone Dipropionate cream applied twice daily, Group. B were treated with 2% Minoxidil solution applied 1ml twice daily, Group. C was treated with 1.15% Anthralin ointment applied daily for 15 minutes and Group. D were treated with 0.03% Tacrolimus applied twice daily to the affected areas. Alopecia Grading Scale (AGS was calculated at first visit and 12 weeks. Regrowth Score (RGS was calculated at 12 weeks. Treatment outcome in different groups were compared using mean AGS at 12 weeks and RGS. RESULTS: Group A patients showed statistically significant clinical improvement when compared to all the other groups. Poorest response was seen in Group D. CONCLUSION : The study concluded that topical 0.05% betamethasone dipropionate is the most effective topical treatment modality in patients with alopecia areata. KEYWORDS: Alopecia areata; Betamethasone dipropionate; Minoxidil; Anthralin; Tacrolimus.

  7. Topical Therapies for Psoriasis: Improving Management Strategies and Patient Adherence.

    Science.gov (United States)

    Stein Gold, Linda F

    2016-03-01

    Psoriasis is a chronic disease that has a substantial effect on quality of life of patients and often needs long-term treatment. Topical treatments for psoriasis include corticosteroids, vitamin D derivatives, tazarotene, anthralin, tacrolimus, pimecrolimus, and newer formulations of tar. Although many of these treatments are effective, they must be prescribed appropriately and used consistently for a period of weeks to months before clinical evidence of improvement can be seen and patients perceive that the treatment is working. As such, medication dosage/schedule, choice of vehicle, and especially patient adherence to medication are key factors for a treatment to be effective. Addressing patient preferences about treatments and concerns about treatment-related toxicities and managing their expectations represent additional aspects of patient care. Therapies such as calcipotriene and betamethasone dipropionate (Cal/BD) fixed combination foam and new drugs and vehicles continuously enhance the treatment landscape for psoriasis. Because adherence to topical treatment can be a major difficulty, keeping the treatment regimen simple and using new and sophisticated treatment vehicles that are acceptable to patients can likely improve treatment outcomes. PMID:27074696

  8. Alopecia areata.

    Science.gov (United States)

    Perera, Eshini; Yip, Leona; Sinclair, Rodney

    2015-01-01

    Alopecia areata (AA) is a common, non-scarring alopecia that usually presents as well-circumscribed patches of sudden hair loss and affects 0.1-0.2% of the population. The aetiology of AA is thought to be both genetic and autoimmune in nature. One hundred and thirty-nine single nucleotide polymorphisms linked to AA have been identified in 8 regions of the genome and have been found to be associated with T cells or the hair follicle. Furthermore, patients with AA have been found to have an increased frequency of hair follicle-specific auto-antibodies. The diagnosis of AA is usually made on clinical grounds, and further investigations are not usually needed. Intralesional corticosteroids remain the treatment of choice. Systemic steroids are also highly effective; however, side effects make them less desirable to both patients and physicians. Other available treatment options include anthralin, minoxidil, topical immunotherapy and systemic immunosuppressants. These treatments will be discussed in depth in this chapter. The morbidity of AA is largely psychological; therefore, the successful treatment of AA should include focusing on improving the psychological impact of this condition. PMID:26370645

  9. Topical Therapies for Psoriasis: Improving Management Strategies and Patient Adherence.

    Science.gov (United States)

    Stein Gold, Linda F

    2016-03-01

    Psoriasis is a chronic disease that has a substantial effect on quality of life of patients and often needs long-term treatment. Topical treatments for psoriasis include corticosteroids, vitamin D derivatives, tazarotene, anthralin, tacrolimus, pimecrolimus, and newer formulations of tar. Although many of these treatments are effective, they must be prescribed appropriately and used consistently for a period of weeks to months before clinical evidence of improvement can be seen and patients perceive that the treatment is working. As such, medication dosage/schedule, choice of vehicle, and especially patient adherence to medication are key factors for a treatment to be effective. Addressing patient preferences about treatments and concerns about treatment-related toxicities and managing their expectations represent additional aspects of patient care. Therapies such as calcipotriene and betamethasone dipropionate (Cal/BD) fixed combination foam and new drugs and vehicles continuously enhance the treatment landscape for psoriasis. Because adherence to topical treatment can be a major difficulty, keeping the treatment regimen simple and using new and sophisticated treatment vehicles that are acceptable to patients can likely improve treatment outcomes.

  10. Childhood psoriasis.

    Science.gov (United States)

    Farber, E M; Nall, L

    1999-11-01

    Psoriasis is a common skin disease in infants, children, and adolescents. A review of the clinical, epidemiologic, genetic, and therapeutic aspects of childhood psoriasis is presented. Population studies indicate that the first signs of psoriatic lesions occur in the pediatric age group, birth to 18 years of age, and that both genetic and environmental factors interact to precipitate the development of psoriasis. Koebner reactions are the result of external or internal triggering factors, such as physical injury to the skin, low humidity, and certain drugs. The most frequently observed variant to psoriasis is the plaque type, followed by guttate psoriasis, and juvenile psoriatic arthritis. Pustular psoriasis and erythrodermic psoriasis are rare forms of the disease, but are seen in children from infancy to adolescence. The scalp is the most frequently affected site of involvement in pediatric psoriasis, followed by the appearance of lesions on the extensor surfaces of the extremities, trunk, and nails. Although not common in adult psoriasis, the face and ears are often involved. Topical medications such as corticosteroids, calcipotriol, coal tar preparations, anthralin formulations, and ultraviolet B are recommended in monotherapy or in combination therapy, whereas psoralen plus ultraviolet A, methotrexate, and retinoids should only be administered in crisis situations. The treatment objectives in childhood psoriasis are to preserve skin surfaces, to afford physical relief from the disease, and to employ treatments that do not endanger the health or future development of the child.

  11. Therapeutic moisturizers as adjuvant therapy for psoriasis patients.

    Science.gov (United States)

    Gelmetti, Carlo

    2009-01-01

    At any point in time, psoriasis affects 2-3% of the world's population and has one of the biggest impacts on quality of life of any dermatological disorder. Treatment is extremely costly and prevention of disease progression in severity and extent is crucial. Psoriasis treatment should include skin hydration (regular use of moisturizers and emollients), careful, gentle skin cleansing, and identification and avoidance of Koebner phenomenon triggers (excoriation, maceration) and infectious foci (Streptococcus pyogenes). Moisturizers have been shown to significantly improve skin conditions and quality of life for psoriasis patients. They are a valuable first-line treatment, as dry skin is common and adds to the irritability of the diseased skin. Most patients respond well to topical treatment with topical corticosteroids, emollients, coal tar, anthralin (dithranol) or calcipotriol. Emollients are the most prescribed products, providing transient relief from irritation and some possessing anti-inflammatory properties. Moisturizers and emollients should be used in the following cases: minimal psoriasis, napkin psoriasis, psoriasis of the folds, psoriatic skin damaged by previous local treatments, and in pregnancy or women of childbearing age.

  12. Lycopene from tomatoes: vesicular nanocarrier formulations for dermal delivery.

    Science.gov (United States)

    Ascenso, Andreia; Pinho, Sónia; Eleutério, Carla; Praça, Fabíola Garcia; Bentley, Maria Vitória Lopes Badra; Oliveira, Helena; Santos, Conceição; Silva, Olga; Simões, Sandra

    2013-07-31

    This experimental work aimed to develop a simple, fast, economic, and environmentally friendly process for the extraction of lycopene from tomato and incorporate this lycopene-rich extract into ultradeformable vesicular nanocarriers suitable for topical application. Lycopene extraction was conducted without a cosolvent for 30 min. The extracts were analyzed and incorporated in transfersomes and ethosomes. These formulations were characterized, and the cellular uptake was observed by confocal microscopy. Dermal delivery of lycopene formulations was tested under in vitro and in vivo conditions. Lycopene extraction proved to be quite safe and selective. The vesicular formulation was taken up by the cells, being more concentrated around the nucleus. Epicutaneous application of lycopene formulations decreased the level of anthralin-induced ear swelling by 97 and 87%, in a manner nonstatistically different from the positive control. These results support the idea that the lycopene-rich extract may be a good alternative to the expensive commercial lycopene for incorporation into advanced topical delivery systems. PMID:23826819

  13. Guidelines of care for the management of psoriasis and psoriatic arthritis Section 3. Guidelines of care for the management and treatment of psoriasis with topical therapies

    Energy Technology Data Exchange (ETDEWEB)

    Menter, A.; Korman, N.J.; Elmets, C.A.; Feldman, S.R.; Gelfand, J.M.; Gordon, K.B.; Gottlieb, A.; Koo, J.Y.M.; Lebwohl, M.; Lim, H.W.; Van Voorhees, A.S.; Beutner, K.R.; Bhushan, R. [University of Texas South West Medical Center Dallas, Dallas, TX (United States)

    2009-04-15

    Psoriasis is a common, chronic, inflammatory, multi-system disease with predominantly skin and joint manifestations affecting approximately 2% of the Population. In this third of 6 sections of the guidelines of care for psoriasis, we discuss the use of topical medications for the treatment of psoriasis. The majority of patients with psoriasis have limited disease (<5% body surface area involvement) and can be treated with topical agents, which generally provide a high efficacy-to-safety ratio. Topical agents may also be used adjunctively for patients with more extensive psoriasis undergoing therapy with either ultraviolet light, systemic or biologic medications. However, the use of topical agents as monotherapy in the setting of extensive disease or in the setting of limited, but recalcitrant, disease is not routinely recommended. Treatment should be tailored to meet individual patients' needs. We will discuss the efficacy and safety of as well as offer recommendations for the use of topical corticosteroids, vitamin D analogues, tazarotene, tacrolimus, pimecrolimus, emollients, salicylic acid, anthralin, coal tar, as well as combination therapy.

  14. Utility of dermoscopy in alopecia areata

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    Mandar Mane

    2011-01-01

    Full Text Available Background: Alopecia areata (AA shows several well-defined dermoscopic features which may help in confirming diagnosis in AA. Aims: We carried out a study to examine the dermoscopic features of AA and develop a protocol for diagnosis of AA by dermoscopy. Materials and Methods: Dermoscopy was performed in 66 patients with AA. Hanse HVS-500NP dermoscope (magnification of ×32 and ×140 was used. Results: The mean age of the patients (46 males and 20 females was 26.85 years. The mean age of onset was 25.15 years. The mean duration of alopecia was 10.3 months. Most common AA in our study was patchy type (57/66, 87.7%. Single patch was seen in 24 patients and multiple patches in 33 patients. Diffuse AA was seen in five patients. Ophiasis and alopecia universalis were seen in two patients each. Nail changes were fine pitting (4, ridging (2, thinning of nail plate (2. Twenty nail dystrophy, distal onycholysis, striate leukonychia and coarse pitting were seen in one patient each. Intralesional triamcinolone acetonide was the most common therapy offered. Others were oral betamethasone minipulse therapy, dexamethasone pulse, minoxidil, anthralin and corticosteroids. The most common dermoscopic finding was yellow dots seen in 54 patients (81.8%, followed by black dots (44 patients, 66.6%, broken hairs (36 patients, 55.4%, short vellus hair (27 patients, 40.9% and tapering hairs (8 patients, 12.1%. Conclusions: The most common dermoscopic finding of AA in our study was yellow dots, followed by black dots, broken hairs, short vellus hair and tapering hairs. Dermoscopic findings were not affected by the type of AA or the severity of the disease.

  15. Psoriasis. A review of recent advances in treatment.

    Science.gov (United States)

    Farber, E M; Nall, L

    1984-10-01

    Current concepts in the treatment of psoriasis are reviewed, including: traditional modalities of dithranol (anthralin), tar, and corticosteroids alone or in combination with other agents; phototherapy and photochemotherapy; experimental studies with the aromatic retinoid etretinate and related analogues; dialysis; and the potential use of hyperthermia. Prudent administration of agents that are known to have serious side effects should be the concern of all clinicians. Many regimens that have beneficial short term results may have the potential for long term sequelae that may not only affect the patient but the offspring as well. Two of the most promising innovative concepts in the therapeutic armamentarium for psoriasis are psoriasis 'day care centres', and prevention and self-care. With the ever-increasing costs of medical care throughout the world, ways and means of reducing costs should be initiated by the clinician when considering a treatment programme. The clinician has the responsibility of determining whether the severity of the disease warrants ambulatory outpatient regimens or hospitalisation. If the patient would benefit from daily attention, then the psoriasis day care centre approach provides an appropriate clinical setting. However, in addition to administering appropriate medication, it is incumbent upon the clinician to educate patients regarding their disease and the triggering factors to prevent exacerbations. 'Disability prevention' means extending the services of clinicians and others to deal systematically with 2 areas involved in disease development; one is recognising the genetic component of psoriasis; the other, environmental triggering factors, e.g. infection, trauma to the skin, low humidity, and stress. Until recently, dermatology has focused on diseases and repairing the damage they cause. Now, the significance of genetic and environmental influences in multifactorial diseases like psoriasis has been realised, as has the importance of

  16. Toward noninvasive microspectrofluorometry of skin lesions for diagnostic and prognostic evaluation of cell metabolism and organelle interactions

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    Hirschberg, Joseph G.; Schachtschabel, Astrid; Kohen, Elli; Kohen, Cahide; Schachtschabel, Dietrich O.

    1995-02-01

    The basic principle of this approach relies on microspectrofluorometric observations of upheavals in the cell's energy metabolism and cell-to-cell metabolic communication in human and mouse melanoma cells. A striking feature is the definition of a highly active nuclear energy metabolism in M8255 human melanoma cells which is characterized by an intense fluorescence response associated with NAD(P) reduction by substrates of glycolysis or the hexose monophosphate shunt. Changes are also expected in the steady state levels of reduced/oxidized NAD(P) in the nuclear, cytoplasmic and mitochondrial compartments, which are probably dependent on ATP levels and distribution (as determined by cell metabolism and eventually the presence of ATP traps). A topographic scanning of skin lesions, either under metabolic steady state conditions or in the presence of permeating substrates, can lead to the recognition of characteristic patterns associated with pigmented and nonpigmented, malignant and nonmalignant skin lesions. The method is, in a way, an extension of microscopic transillumination techniques which have led to the identification of specific patterns associated with such lesions. However, here, a new dimension is added by introduction of fluorescence evaluations. This can represent the first step in a multiparameter approach to the non-invasive in situ fluorescence scan of dermatological lesions by inclusion of: (1) fluorescence excitation and emission spectra; (2) new fluorescence probes of cytoplasmic organelles and nuclear components. Primary emphasis should be placed on the highly active nuclear energy metabolism, which can be triggered to maximum levels when the role of mitochondria as the `cells's policeman' with regard to metabolic control is suppressed by use of topically cytotoxic agents such as the `antipsoriatic' anthralin and dicarboxylic acids used in the local treatment of melanoma. Fluorescence excitation spectroscopy may be of particular advantage in

  17. Retrospective evaluation of childhood alopecia areata cases

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    Munise Daye

    2013-09-01

    Full Text Available Background and design: Approximately 20% of alopecia areata (AA cases are children. There is limited information about childhood AA.We aimed to examine demographic features,treatments and diseases prognosis of child cases of AA that were followed in our clinic. Material and methods: Datas of 110 AA patients who are 16 and under 16 years old were examined retrospectively.The age,gender,disease onset age,duration of disease,types of AA and onset area,nail involvement, accompanying systemic and dermatological diseases,laboratory tests,treatments and the prognosis were evaluated in their follow-up time.Results: Female cases were 46,4%, male cases were 53,6%.The mean age was 10,35 years.The age of disease onset was 8,65 years.Primary onset areas of AA cases were scalp in 83,6%, eyebrows in 5,4%, body hair in 5,4%, eyelashes in 2,7%, eyebrows and eyelashes in 2,7%.Types of disease were AA in 73,4% cases,alopecia totalis in 19% cases, alopecia universalis in 5,4% cases,ophiaisis in 1,8% cases.Nail involvement was established in 36,3% cases. Nevus flammeus was established in 2,7% cases.Mean disease duration was 17,02 months.Accompaying dermatosis were vitiligo in 2,7% cases,atopic dermatitis in 6,3% cases. The accompaying systemic diseases were autoimmune thyroiditis in 1,8% cases and Down's Syndrome in 2,7% cases.Thyroid autoantibodies were high in 0,9% cases.We have treated 24,5% of cases with topical corticosteroid lotion, 30,9% of cases with anthralin, 0,9%of cases with 2% minoxidil lotion, 0,9% of cases with calcipotriol lotion, 1,8% of cases with topical calcineurin inhibitors, 10% of cases with intralesional corticosteroids.We have treated 15,4% of cases with systemic corticosteroids and PUVA therapy who were resistant to topical treatment.We have treated 14,5% of cases with different combinations of topical treatments.Remission was observed in 34,5% of cases.The mean remission duration was 12.2 months.Relapse was observed at a average of two

  18. Application of the improved BALB/c 3T3 cell transformation assay to the examination of the initiating and promoting activities of chemicals: the second interlaboratory collaborative study by the non-genotoxic carcinogen study group of Japan.

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    Tsuchiya, Toshiyuki; Umeda, Makoto; Tanaka, Noriho; Sakai, Ayako; Nishiyama, Hiroshi; Yoshimura, Isao; Ajimi, Syozo; Asada, Shin; Asakura, Masumi; Baba, Hiroshi; Dewa, Yasuaki; Ebe, Youji; Fushiwaki, Yuichi; Hagiwara, Yuji; Hamada, Shuichi; Hamamura, Tetsuo; Iwase, Yumiko; Kajiwara, Yoshitsugu; Kasahara, Yasushi; Kato, Yukihiko; Kawabata, Masayoshi; Kitada, Emiko; Kaneko, Kazuko; Kizaki, Yuko; Kubo, Kinya; Miura, Daisaku; Mashiko, Kaori; Mizuhashi, Fukutaro; Muramatsu, Dai; Nakajima, Madoka; Nakamura, Tetsu; Oishi, Hidetoshi; Sasaki, Toshiaki; Shimada, Sawako; Takahashi, Chitose; Takeda, Yuko; Wakuri, Sinobu; Yajima, Nobuhiro; Yajima, Satoshi; Yatsushiro, Tomoko

    2010-03-01

    The Non-genotoxic Carcinogen Study Group in the Environmental Mutagen Society of Japan organised the second step of the inter-laboratory collaborative study on one-stage and two-stage cell transformation assays employing BALB/c 3T3 cells, with the objective of confirming whether the respective laboratories could independently produce results relevant to initiation or promotion. The method was modified to use a medium consisting of DMEM/F12 supplemented with 2% fetal bovine serum and a mixture of insulin, transferrin, ethanolamine and sodium selenite, at the stationary phase of cell growth. Seventeen laboratories collaborated in this study, and each chemical was tested by three to five laboratories. Comparison between the one-stage and two-stage assays revealed that the latter method would be beneficial in the screening of chemicals. In the test for initiating activity with the two-stage assay (post-treated with 0.1microg/ml 12-O-tetradecanoylphorbol-13-acetate), the relevant test laboratories all obtained positive results for benzo[a]pyrene and methylmethane sulphonate, and negative results for phenanthrene. Of those laboratories assigned phenacetin for the initiation phase, two returned positive results and two returned negative results, where the latter laboratories tested up to one dose lower than the maximum dose used by the former laboratories. In the exploration of promoting activity with the twostage assay (pretreated with 0.2microg/ml 3-methylcholanthrene), the relevant test laboratories obtained positive results for mezerein, sodium orthovanadate and TGF-beta1, and negative results for anthralin, phenacetin and phorbol. Two results returned for phorbol 12,13-didecanoate were positive, but one result was negative - again, the maximum dose to achieve the latter result was lower than that which produced the former results. These results suggest that this modified assay method is relevant, reproducible and transferable, provided that dosing issues, such as the