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A quantitative method for the assay of phenol in ointments is described. The procedure involves the formation of a blue indophenol by reacting phenol with 2,6-dibromoquinone-4-chloroimide which can be measured spectrophotometrically. The method is accurate, and interference from other active ingredients (hydrocortisone and menthol) does not occur.
PURPOSE: To evaluate the efficacy of a fluoride dentifrice containing a fixed combination of essential oils (Thymol, Menthol, Eucalyptol, and Methyl Salicylate) in preventing caries in Sprague Dawley rats. MATERIALS AND METHODS: The dentifrice contains 0.76% sodium monofluorophosphate (SMFP) as the fluoride source and a silica abrasive system. A fluoride-free placebo and a clinically proven USP dentifrice reference standard for SMFP/silica were included as controls. Three groups of 45 SDV-free Sprague Dawley weanlings were infected by a cariogenic strain of Streptococcus sobrinus and fed cariogenic diet NIH 2000 ad libitum. Animals were treated twice daily (once on weekends) with the assigned dentifrice using a cotton-tipped applicator, for 5 wks, after which they were terminated and caries scored using Larson's modification of the Keyes method. RESULTS: Analyses of variance were used to compare inter-group means, the total E lesion score was the primary efficacy variable. Compared with the fluoride-free vehicle control, the experimental dentifrice and USP reference standard dentifrice produced a statistically significant reductions of 18.3% and 12.2% respectively for total caries score (P<0.001). Compared with the clinically tested USP positive control dentifrice, the experimental dentifrice produced a statistically significant reduction in the total caries score of 6.9% (P=0.028). The results of this study show that 1) both the new dentifrice containing essential oils and USP dentifrice are statistically significantly effective in reducing caries in the rat model, 2) the anticaries activity of the SMFP dentifrice is not adversely affected with the addition of essential oils.
PURPOSE: To determine the effect of 6 months use of an essential oil-containing (EO) antiplaque/antigingivitis fluoride dentifrice on the balance of the oral microbial flora and on the emergence of resistant microbial forms by analysis of dental plaque and saliva. MATERIALS AND METHODS: The dentifrice essential oils consisted of a fixed combination of thymol, menthol, methyl salicylate, and eucalyptol. An identical fluoride-containing dentifrice without the essential oils served as the control. A subgroup of 66 subjects from a clinical trial population of 321 was randomly selected for characterization of their dental plaque microflora. Saliva was also cultured to monitor for the emergence of opportunistic pathogens. Supragingival plaque and saliva were harvested at baseline, after which subjects received a dental prophylaxis. Subjects were sampled again after 3 and 6 months of product use prior to clinical examination. Plaque was characterized for microbial content by phase contrast microscopy for recognizable cellular morphotypes and by cultivation on nonselective and selective culture media. Determination of the minimum inhibitory concentrations of the test agent against selected Actinomyces and Veillonella isolated bacterial species was conducted at all time points to monitor for the potential development of bacterial resistance. RESULTS: There were no statistically significant differences between the microbial flora obtained from subjects using the essential oil-containing dentifrice and the vehicle control for all parameters and time periods except for the percentage of spirochetes at 6 months and for percentage of "other" microorganisms at 3 months. The EO group exhibited a lower adjusted mean for both parameters. Additionally, there was no evidence of the development of bacterial resistance to the antimicrobial activity of the essential oils or the emergence of opportunistic pathogens.
A case of microscopic hemorrhage into the anterior chamber is described. Slit-lamp examination disclosed a steady fine stream of blood issuing from a tiny grayish bulblike microhemangioma at the pupillary border. Fluorescein biomicroscopy revealed several similar microhemangiomas on the borders of each pupil. It is presumed that minor ocular irritation, due either to poison ivy or to a menthol (0.70%) cream which the patient applied to her face, precipitated the microhyphema.
In this report we demonstrate that retinoic acid (RA) down-regulated the number of IL-6R on human leukocyte cell lines, including the myeloma cell line AF10, and two B cell hybridomas that correspond to cells at earlier stages of B cell development. Using AF10 cells, whose growth was determined to be mediated by the autocrine action of IL-6, we found that RA reduction of IL-6R was concentration-dependent over a range of 10(-11) to 10(-5) M and corresponded to the ability of the retinoid to inhibit cell proliferation. The down-regulation of IL-6R number by RA was accompanied by reduced IL-6R mRNA expression. RA did not affect endogeneous IL-6 synthesis or secretion from AF10 cells. However, addition of exogenous rIL-6 could overcome RA-induced growth inhibition. Menthol, a structurally unrelated compound to RA, also suppressed IL-6R expression and, correspondingly, inhibited cell growth. Taken together, our results suggest that the antiproliferative action of RA on AF10 cells is caused by reduction of IL-6R expression and subsequent inhibition of IL-6-mediated autocrine growth. These findings suggest the possibility that down-regulation of IL-6R is a means by which RA can modulate immune function.
The individual enzyme inducibility was studied with methods of menthol loading and sulphobromophthalein in groups of patients with low and average metabolism. Both methods are suitable for testing inducible conjugation systems by providing indirect information on the rate of drug elimination. In the low-metabolism groups the response in per cent correlated inversely with the initial value, and the changes were significant not only in the low but also in the average-metabolism group at the end of 30 days of phenobarbital treatment. The results are discussed with regard to the avoidability of undesired drug effects.
There are some controversies regarding the effect of (+)-cyanidanol-3 on hepatic drug metabolism. In the present study the effect of (+)-cyanidanol-3 was investigated on the microsomal and mitochondrial enzyme functions (hydroxylation, glucuronide production, D-glucaric acid excretion and acetylation) in alcoholic liver disease. Eight patients with biopsy-proven chronic alcoholic hepatitis were investigated before and after a 10-day, as well as after a further 30-day, treatment with (+)-cyanidanol-3 (Catergen), 3000 mg/day orally. Besides biochemical liver function tests (serum bilirubin levels, GOT, GGT), antipyrine metabolic clearance rate, mentholglucuronide production, urinary D-glucaric acid excretion and sulphadimidine kinetics were determined. Biochemical liver function tests improved markedly after the first period of treatment, at the same time antipyrine metabolic clearance rate decreased. Menthol-glucuronide production and D-glucaric acid excretion decreased significantly only after the second two course of Catergen administration. Sulphadimidine kinetics was not remarkably changed. Our findings suggest that (+)-cyanidanol-3 inhibits the hepatic microsomal drug metabolizing enzyme function in chronic alcoholic hepatitis.
Diapulmon (Chinoin) which comprise camphor, 1-menthol, eucalyptus oil and quinine dissolved in sunflower oil (Oleum helianthi) is marketed in ampoules of 2 ml but utilized almost exclusively for inhalation therapy. Complexing the active ingredients of Diapulmon with beta-cyclodextrin (beta-CD) a stable non hygroscopic microcrystalline substance is obtained. When this powder sprinkled on hot water, the included volatile compounds are gradually released and the desired pharmacological effect can be brought about.
The biochemical liver function tests form an integral part of diagnostic practice in hepatology. In this study the parameters suited for the estimation of drug elimination and of the induced state of the liver, thus the excretion of D-glucaric acid, of menthol glucuronide and the parameters of antipyrine and sulphadimidine kinetics were correlated with the results of biochemical laboratory tests in patients with chronic liver disease. The aim was to establish universally valid quantitative correlations between the above results. Multiple relationships were revealed, but generally valid correlations for the group of liver diseases occurred only in special relationships (serum albumin level and antipyrine T1/2; serum bilirubin level and sulphadimidine T1/2). The results have been evaluated from the methodological aspect to work out an appropriate dosage regime in liver diseases.
The enzyme inductive effect of flumecinol (Zixoryn, RGH-3332), a new hepatic enzyme inducer, was studied in healthy volunteers. The dosages employed were as follows: 25, 50, 100, 200, 400, 600 and 800 mg single doses; and during a 7-day period single doses of 50 mg daily, and doses of 200, 300 and 400 mg three times daily. The intensity of enzyme induction was measured by the following parameters: antipyrine metabolic clearance, D-glucaric acid excretion, menthol loading, and total serum bilirubin. The minimal and optimal inductive doses of flumecinol were determined. A single dose of 600 mg of flumecinol is recommended at intervals of 7 days. This dosage also induces the first and the second phases of reactions. The induction effect becomes manifest after 24 hours. Its peak is reached between 48 and 96 hours, and the inductive activity ceases between 216 and 408 hours.
The addition of a chiral alcohol, such as l-menthol or R-(-)-2-octanol, to an achiral nitrosamine causes a dissymmetric perturbation of the symmetrical chromophore and a Cotton effect is evident in the circular dichroism curve at the wavelength of ultraviolet absorption of the nitrosamine function. The intensity (ellipticity) of this induced circular dichroism is concentration dependent and appears to result from a weak 1:1 complex of nitrosamine and alcohol. The implications of these observations for structural studies are considered.
Chromosome aberrations can occur by secondary mechanism(s) associated with cytotoxicity, induced by chemicals that do not attack DNA. Aberrations are formed from DNA double-strand breaks, and DSBs are known to be induced by nonmutagenic (Ames test negative) noncarcinogens at toxic levels [Storer et al. (1996): Mutat Res 368:59-101]. Here, 8 of 12 of these chemicals caused aberrations in CHO cells at cytotoxic doses, and often only when cell counts (survival) at 20 hr approached < or =50% of controls. Five of eight noncarcinogens (2,4,-dichlorophenol, dithiocarb, menthol, phthalic anhydride, and ethionamide) and one of two equivocal carcinogens (bisphenol A) caused aberrations, usually over a narrow dose range with steeply increasing cytotoxicity. Phthalic anhydride and ethionamide were positive only at doses with precipitate. Phenformin was negative even at toxic doses and ephedrine and phenylephrine were negative and gave little toxicity. Aberrations were also induced by metabolic poisons, 2,4-dinitrophenol, (uncouples oxidative phosphorylation), and sodium iodoacetate, (Nal; blocks ATP production). Five of the chemicals that induced aberrations in CHO cells were tested in human TK6 cells and four were positive, the fifth being equivocal. Stable aberrations (translocations) were induced in human cells by Nal. Clearly, chemicals can give "false-positive" results in the chromosome aberration assay at cytotoxic levels, though cytotoxicity does not always produce aberrations, so that further information (e.g., DNA reactivity) is needed to determine whether a result is a "false-positive." Primary DNA-damaging chemicals such as alkylators are also cytotoxic, but give strong increases in aberrations without marked initial toxicity by the measures used here, although the aberrations they induce do reduce long-term survival in colony-forming assays.
Myrtol standardized (Gelomyrtol/Gelomyrtol forte) inhibits the activity of 5-lipoxygenase of human basophil and eosinophil leukocytes and the formation of leukotriene C4 as well as 1.8-cineole (eucalyptol). An increase of prostaglandins (PGE2) in mucous membranes of teat cisterns after topical administration of TPA (tetradecanoylphorbol-13-acetate) was inhibited. In vitro and in vivo studies revealed spasmolytic and broncholytic effects of Myrtol stand. After topical administration into the teat cisterns of the isolated bovine udder Myrtol stand. increased the surface temperature, comparable to effects of menthol.
Optical resolution of racemic N-benzyloxycarbonyl-protected alpha-alkoxyglycines, (+/-)-Cbz-Gly(OR)-OH (R = Et and Pr(i)), was achieved by means of fractional crystallization of diastereomeric salts with (+)-(1S,2S)-2-amino-1-phenyl-1,3-propanediol or diastereomeric esters of (+)- or (-)-menthol. The D- and L-configurations were assigned to the (+)- and (-)-Cbz-Gly(OR)-OH, respectively, based on L-enantioselective enzymatic hydrolysis of (+/-)-Cbz-Gly(OR)-OR' (R = Me, Et, and Pr(i); R' = CH(2)CF(3) and Me) using porcine pancreatic lipase and papain. Chiroptical properties and HPLC retention times of D- and L-Gly(OR)-residue (R = Me and Pr(i))-containing peptides were compared in relation to their configurational assignments. Copyright 1999 Wiley-Liss, Inc.
A new procedure for the synthesis of 1,3,4-trisubstituted and 1,4-disubstituted pyrrolidin-2-one derivatives in an enantioselective fashion is reported. The 1,3-dipolar cycloaddition of (+/-)-menthol and (-)-8-phenylmenthol derived Fischer alkoxy alkenyl carbene complexes with in situ generated functionalized azomethine ylides gives the corresponding cycloadducts as chelated tetracarbonyl Fischer carbene complexes. Only one regioisomer is detected in all cases, and the diastereoselectivity of the reaction is very high when (-)-8-phenylmenthol derived carbenes are employed. Oxidation and further transformation of the cycloadducts provide an easy access to pyrrolidin-2-ones. The anti-inflammatory and antidepressant drug (+)-Rolipram is readily prepared in four steps in a 20% overall yield by taking advantage of this newly developed methodology.
Iridium(I) complexes containing a (5H-dibenzo[a,d]cyclohepten-5-yl)-phosphane (tropp(R); R = phosphorus-bound substituent = Ph, Cyc) as a rigid, concave-shaped, mixed phosphane olefin ligand were prepared and tested as catalyst precursors in the hydrogenation of imines. With the complex [Ir(tropp(Cyc))(cod)]OTf, turnover frequencies (TOFs) of >6000 h(-1) were reached in the hydrogenation of N-phenyl-benzylidenamine, PhN==CHPh. Lower activities (TOF>80 h(-1)) are observed with N-phenyl-(1-phenylethylidene)amine, PhN==CMePh. Chiral tropp-type ligands were prepared in few simple steps. Monosubstitution of the olefinic unit in the dibenzo[a,d]cycloheptenyl moiety with (R)- or (S)-mentholate gave mixtures of diastereomers that could be separated and isolated in enantiomerically pure form. Iridium(I) complexes with these ligands are rare examples of side-on bonded enolether complexes. In catalytic imine hydrogenations, complete conversion (>98 %) was reached in all cases (conditions: p[H(2)] = 50 bar, T = 50 degrees C, t = 2 h, substrate/catalyst 100:1). The best enantiomeric excess (ee = 86 % S isomer) was reached with PhN==CMePh as substrate and the R,R form of the (10-menthyloxy-5H-dibenzo[a,d]cyclohepten-5-yl)diphenylphosphane ligand. The iridium(I) complex containing the same phosphane gave a 60 % ee (S isomer) with the enamide N-(1-phenylvinyl)acetamide as substrate (conditions: p[H(2)] = 4 bar, T = 50 degrees C, t = 18 h, substrate/catalyst = 50:1). These reactions constitute the first examples in which chiral olefins have been used as steering ligands in catalytic enantioselective hydrogenations.
A novel methodology using a chiral molecular tool of MalphaNP acid (1), 2-methoxy-2-(1-naphthyl)propionic acid, useful for preparation of enantiopure secondary alcohols and determination of their absolute configurations by the (1)H NMR anisotropy method was developed; racemic MalphaNP acid (1) was enantioresolved with (-)-menthol, and the enantiopure MalphaNP acid (S)-(+)-(1) obtained was allowed to react with racemic alcohol, yielding a mixture of diastereomeric esters, which was clearly separated by HPLC on silica gel. By applying the sector rule of (1)H NMR anisotropy effect, the absolute configuration of the first-eluted MalphaNP ester was unambiguously determined. Solvolysis or reduction of the first-eluted MalphaNP esters yielded enantiopure alcohols.
The transient receptor potential (TRP) superfamily of cation channels contains four temperature-sensitive channels, named TRPV1-4, that are activated by heat stimuli from warm to that in the noxious range. Recently, two other members of this superfamily, TRPA1 and TRPM8, have been cloned and characterized as possible candidates for cold transducers in primary afferent neurons. Using in situ hybridization histochemistry and immunohistochemistry, we characterized the precise distribution of TRPA1, TRPM8, and TRPV1 mRNAs in the rat dorsal root ganglion (DRG) and trigeminal ganglion (TG) neurons. In the DRG, TRPM8 mRNA was not expressed in the TRPV1-expressing neuronal population, whereas TRPA1 mRNA was only seen in some neurons in this population. Both A-fiber and C-fiber neurons expressed TRPM8, whereas TRPV1 was almost exclusively seen in C-fiber neurons. All TRPM8-expressing neurons also expressed TrkA, whereas the expression of TRPV1 and TRPA1 was independent of TrkA expression. None of these three TRP channels were coexpressed with TrkB or TrkC. The TRPM8-expressing neurons were more abundant in the TG compared with the DRG, especially in the mandibular nerve region innervating the tongue. Our data suggest heterogeneity of TRPM8 and TRPA1 expression by subpopulations of primary afferent neurons, which may result in the difference of cold-sensitive primary afferent neurons in sensitivity to chemicals such as menthol and capsaicin and nerve growth factor.