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16,17-Dihydro-11-methoxy-15H-cyclopenta[]phenanthrene was synthesizedby two different routes and tested for carcinogenicity in TylersOriginal (TO) and SENCAR strain of mice by repeated applicationand initiation/promotion regime. 16, 17-Dihydro-11-hydroxy-15H-cyclopenta[]phen-anthrenewas also tested for carcinogenicity in the TO strain by repeatedapplication. Surprisingly with both of these compounds, whichlack conjugation in ring D, one of the ingredients essentialfor biological activity appears to be carcinogenic. It is temptingto speculated whether these compounds undergo metabolic oxidationin the skin at the benzylic C-17 position. 相似文献
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Structure-activity relationships for epidermal ornithine decarboxylase induction and skin tumor promotion by anthrones 总被引:2,自引:0,他引:2
DiGiovanni John; Kruszewski Francis H.; Coombs Maurice M.; Bhatt Tarlochan S.; Pezeshk Abbas 《Carcinogenesis》1988,9(8):1437-1443
The present study was designed to compare the skin tumor promotingand epidermal ornithine decarboxylase (ODC) inducing activitiesof various structural analogs of anthralin (1, 8-dihydroxy-9-anthrone)and chrysarobin (1, 8-dihydroxy-3- methyl-9-anthrone). Groupsof 30 SENCAR mice each were initiated with 7, 12-dimethylbenz[a]anthraceneand 2 weeks later promoted with once- or twice-weekly applicationsof various doses of these anthrone derivatives. Carbon-10 (C10)-acylderivatives of anthralin were active skin tumor promoters inthe range of 25440 nmol per mouse. 10-Acetylanthralinwas significantly more active than 10-myristoyl-anthralin atlow doses (e.g. 25 and 50 nmol per mouse) and nearly as potentas the unsubstituted compound. Higher doses ( 100 nmol per mouse)of this derivative were toxic, hence, reducing the final papillomaresponse. On a relative activity scale where anthralin is 1.0,these derivatives had activities that were 0.7 and 0.2, respectively.10, 10-Dipropylanthralin was totally inactive at the doses tested.C6-Substituted derivatives of chrysarobin demonstrated diversetumor promoting activities when tested in the range of 25440nmol per mouse. On a relative activity scale where chrysarobinis 1.0, 6-methoxychrysarobin (physcion anthrone) was 0.9, whereas6-hydroxychrysarobin (emodin anthrone) had no activity. Chrysophanicacid (1, 8-dihydroxy-3-methyl-9, 10-anthraquinone) was alsoinactive as a tumor promoter at the doses tested. In general,the tumor promoting activities of these anthrone derivativescorrelated very well with their ability to induce epidermalODC after a single topical application indicating an importantrole for this enzyme in skin tumor promotion by anthones. Theability of C10-substituted derivatives of anthralin to undergobase catalyzed oxidation in vitro correlated with both ODC inducingand tumor promoting activities. In addition, copper(II) bis(diisopropylsalicylate)was found to inhibit both ODC induction and skin tumor promotionby chrysarobin. These latter data, when taken together, suggesta role for oxidation at C10 in skin tumor promotion by anthronederivatives. 相似文献
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The use of atropine sulphate in the paediatric age group as a premedicant orally in a dosage of 0.02 mg/kg body weight 70 minutes prior to surgery was found to be as effective as atropine sulphate given intramuscularly 35 minutes prior to surgery in a dosage of 0.01 mg/kg body weight. This avoids the unpleasant memory of needle prick; The duration of effect as studied in the normal healthy children not subjected to surgery was found to be 2 1/2-3 hours. 相似文献
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Bhatt AD Dalal DG Shah SJ Joshi BA Gajjar MN Vaidya RA Vaidya AB Antarkar DS 《Journal of postgraduate medicine》1995,41(1):5-7
An open comparative trial was conducted in 58 adult obese patients (Body Mass Index > or = 25 kg/square metre). Group I (n = 27), non-drug, was advised diet (1200-1600 cals) and a brisk walk for 30 minutes. Group II, in addition, received Guggulu (Medohar) 1.5-3 gms/day for 30 days. Mean difference in weight loss between Guggulu and non-drug group was 0.32 kg (ns) on day 15 and 0.58 kg on day 30 (ns). The mean weight reduction in patients (> 90 kgs) was 1.92 kg (ns) and 2.25 kg (ns) higher in Guggulu group. All patients weighing > 90 kg lost weight in Guggulu group whilst 3 in non-drug group did not lose weight. Guggulu was tolerated well. The data from this pilot study suggest a synergistic diet-Guggulu interaction over 30 days in patients weighing > 90 kgs which needs to be confirmed in a large placebo controlled study. 相似文献
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Interphase cytogenetics using biotin and digoxigenin labelled probes II: Simultaneous differential detection of human and papilloma virus nucleic acids in individual nuclei. 总被引:1,自引:8,他引:1 下载免费PDF全文
C S Herrington J Burns A K Graham B Bhatt J O McGee 《Journal of clinical pathology》1989,42(6):601-606
A method was developed for the simultaneous detection of viral and human DNA in contrasting colours in routine formalin fixed, paraffin wax embedded biopsy specimens. This was achieved by non-isotopic in situ hybridisation (NISH) with a biotinylated Y chromosome probe and digoxigenin labelled probe for human papilloma virus type 6 (HPV 6). The tissues studied were peripheral lymphocytes, tonsil, and penile warts. The hybridisation signals produced by biotinylated probes were visualised in red using streptavidin peroxidase and those produced by digoxigenin labelled probes as a blue/black colour using anti-digoxigenin alkaline phosphatase. In lymphocytes and tonsil 95-100% of cells had a detectable Y chromosome; in warts only 60-70% of infected keratinocytes near the skin surface had a demonstrable Y chromosome. This suggests that this chromosome is lost or occluded in cell maturation. In simultaneous double hybridisation with both probes, HPV and Y sequences were demonstrable within the same nucleus in penile warts. This technique permits the simultaneous differential detection of two nuclei acid sequences in interphase nuclei and will have application in analysis of putative dual HPV infections and in determining the intranuclear spatial relations between nucleic acids in interphase nuclei. 相似文献