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1.
PEGs Soy Sterol are polyethylene glycol (PEG) derivatives of soybean oil sterols used in a variety of cosmetic formulations as surfactants and emulsifying agents, skin-conditioning agents, and cleansing and solubilizing agents. When the safety of these ingredients were first reviewed, the available data were insufficient to support safety. New data have since been received and the safety of these ingredients in cosmetics has been substantiated. Current concentration of use ranges from a low of 0.05% in makeup preparations to 2% in moisturizers and several other products. PEGs Soy Sterol are produced by the reaction of the soy sterol hydroxyl with ethylene oxide. In general, ethoxylated fatty acids can contain 1,4-dioxane as a byproduct of ethoxylation. The soy sterols include campesterol, stigmasterol, and beta-sitosterol. The distribution of sterols found in oils derived from common plants is similar, with beta-sitosterol comprising a major component. Impurities include sterol hydrocarbons and cholesterol (4% to 6%) and triterpine alcohols, keto-steroids, and other steroid-like substances (4% to 6%). No pesticide residues were detected. PEGS: Because PEGs are an underlying structure in PEGs Soy Sterols, the previous assessment of PEGs was considered. It is generally recognized that the PEG monomer, ethylene glycol, and certain of its monoalkyl ethers are reproductive and developmental toxins. Given the methods of manufacture of PEGs Soy Sterol, there is no likelihood of ethylene glycol or its alkyl ethers being present. Also, the soybean oil sterol ethers in this ingredient are chemically different from the ethylene glycol alkyl ethers of concern. PEGs are not carcinogenic, although sensitization and nephrotoxicity were observed in burn patients treated with a PEG-based cream. No evidence of systemic toxicity or sensitization was found in studies with intact skin. Plant Phytosterols: Intestinal absorption of ingested plant phytosterols is on the order of 5%, with 95% of the material entering the colon. Absorbed plant phytosterols are transported to the blood. Although there are some data suggesting that sulfates of beta-sitosterol can act as abortifacients in rats and rabbits, other studies of well-characterized plant phytosterols and phytosterol esters demonstrated no effect in an estrogen-binding study, a recombinant yeast assay for estrogen or estrogen-like activity, or a juvenile rat uterotrophic assay for estrogen or estrogen-like activity. In a two-generation reproduction study using rats, plant phytosterol esters in the diet had no effect on any parameter of reproduction or fertility. Subcutaneous injections of beta-sitosterol did reduce sperm concentrations and fertility in rats. Sitosterol inhibited tumor promoting activity of 12-O-tetradecanoylphorbol-13-acetate (TPA) in mice after initiation with 7,12-dimethylbenz[a]anthracene (DMBA), and reduced the tumors produced by N-methylnitrosourea in rats. Phytosterols were not genotoxic in several bacterial, mammalian, and in vitro assay systems. Phytosterols decreased epithelial cell proliferation in the colon of mice and rats, and were cytotoxic for human epidermoid carcinoma of the nasopharynx. PEGs Soy Sterols: The acute oral LD50 in rats of PEG-5-25 Soy Sterol was >10 g/kg. The acute dermal LD50 of a liquid eyeliner containing 2%PEG-5 Soy Sterol was >2 g/kg in rabbits. PEG-5-25 Soy Sterol was not a primary irritant in rabbits when applied undiluted. Undiluted PEG-5 Soy Sterol did not cause sensitization in guinea pigs. PEGs Soy Sterol did not produce ocular toxicity in rabbits. PEG-5 Soy Sterol was negative in the Ames mutagenicity test, with or without metabolic activation. PEG-5 Soy Sterol, at concentrations up to 2%in formulation, did not cause dermal or ocular irritation, dermal sensitization, or photosensitization in clinical studies. Because of the possible presence of 1,4-dioxane reaction product and unreacted ethylene oxide residues, it was considered necessary to use appropriate procedures to remove these from PEGs Soy Sterol before blending them into cosmetic formulations. Based on the systemic toxicity and sensitization seen with PEGs applied to damaged skin, it was recommended that PEGs Soy Sterol should not be used in cosmetic products applied to damaged skin. Although no dermal absorption data were available, oral studies demonstrate that phytosterols and phytosterol esters are not significantly absorbed and do not result in significant systemic exposure. Some small amounts did appear in the ovaries, however. This raises a concern about the potential presence of free phytosterols and beta-Sitosterol, which could have antiestrogenic, antiprogestational, gonadotrophic, antigonadotrophic, and antiandrogenic effects in PEG sterols. These concerns are alleviated by the extensive data showing that well-defined phytosterols and phytosterol esters are not estrogenic and do not pose a hazard to reproduction. Likewise, the absence of impurities in plant phytosterols and phytosterol esters and extensive data demonstrating the absence of any genotoxicity in bacterial and mammalian systems mitigate against the possibility of any carcinogenic effect with those same well-characterized materials. The Cosmetic Ingredient Review (CIR) Expert Panel concluded that the PEGs Soy Sterol are safe as used in cosmetic products.  相似文献   

2.
目的:对头孢曲松钠中的三嗪环进行定性定量测定,可以控制其残留总量,减少过敏反应的发生,促进工艺改进。方法:本文采用质谱(MS)、红外吸收光谱(IR)与核磁共振谱(NMR),对获得的三嗪环参照品进行结构确认,然后用高效液相色谱法(HPLC)对其在头孢曲松钠中的残留进行定量测定。结果:表明所获得的三嗪环参照品纯度很高,能够对头孢曲松钠作定性定量分析。结论:头孢曲松钠中三嗪环的残留在安全限度之中。  相似文献   

3.
Verticillium sp. SPC-15898 was found to produce novel metabolites, designated ES-242-2-(-)8, which were structurally related to ES-242-1. These compounds were isolated from the culture broth and the physico-chemical and biochemical properties were examined. ES-242-2-(-)8 inhibited [3H]thienyl cyclohexypiperidine ([3H]TCP) binding to rat crude synaptic membranes (CSM) with IC50 values of 0.116, 2.9, ca. 2.9, 25.3, 1.0, 59, 24, and 13 microM, respectively. None of these compounds showed inhibitory effects against the binding of [3H]kainate to its receptor, which is another subtype of the excitatory amino acid receptor.  相似文献   

4.
The beta-D-glucuronides of 2,3-, 3,4-, and 2,6-dichlorophenol (1-3) were prepared by a modified Koenigs-Knorr synthesis. As the alkaline hydrolysis of perpivaloylated methyl (2,3-dichlorophenyl)-glucuronate 1a led to a dehydrated glucuronide, the preparation of peracetylated methyl dichlorophenylglucuronates with subsequent cleavage of the ester bindings under mild conditions was preferred.  相似文献   

5.
Aza-peptide Michael acceptors are a novel class of inhibitors that are potent and specific for caspases-2, -3, -6, -7, -8, -9, and -10. The second-order rate constants are in the order of 10(6) M(-1) s(-1). The aza-peptide Michael acceptor inhibitor 18t (Cbz-Asp-Glu-Val-AAsp-trans-CH=CH-CON(CH(2)-1-Naphth)(2) is the most potent compound and it inhibits caspase-3 with a k(2) value of 5620000 M(-1) s(-1). The inhibitor 18t is 13700, 190, 6.4, 594, 37500, and 173-fold more selective for caspase-3 over caspases-2, -6, -7, -8, -9, and -10, respectively. Aza-peptide Michael acceptors designed with caspase specific sequences are selective and do not show any cross reactivity with clan CA cysteine proteases such as papain, cathepsin B, and calpains. High-resolution crystal structures of caspase-3 and caspase-8 in complex with aza-peptide Michael acceptor inhibitors demonstrate the nucleophilic attack on C2 and provide insight into the selectivity and potency of the inhibitors with respect to the P1' moiety.  相似文献   

6.
The metabolism of three tetrachlorobenzene isomers (TeCB) was investigated in the squirrel monkey. The animals were administered orally 6 single doses of 14C-labeled 1,2,3,4-, 1,2,4,5-, or 1,2,3,5-tetrachlorobenzene over a 3-wk period at levels ranging from 50 to 100 mg/kg body weight (b.w.) and kept in individual metabolism cages to collect urine and feces for radioassay. Approximately 38% (1,2,3,4-TeCB), 36% (1,2,3,5-TeCB), and 18% (1,2,4,5-TeCB) of the doses were excreted respectively in the feces 48 h postadministration. In monkeys dosed with 1,2,3,4-TeCB, unchanged compound accounted for 50% of the fecal radioactivity; its fecal metabolites were identified as 1,2,4,5-tetrachlorophenol (TeCP, 22%), N-acetyl-S-(2,3,4,5-tetrachlorophenyl) cysteine (18%), 2,3,4,5-tetrachlorophenyl sulfinic acid (3%), 2,3,4-trichlorophenyl methyl sulfide (0.6%), and 2,3,4,5-tetrachlorophenyl methyl sulfide (0.2%). As was the case with 1,2,3,4-TeCB, unchanged compound accounted for more than 50% of the fecal radioactivity found in the monkeys dosed with 1,2,3,5-TeCB. The fecal metabolites of 1,2,3,5-TeCB consisted of 2,3,4,5-TeCP (2%), 2,3,4,6-TeCP (14%), 2,3,5,6-TeCP (9%), and 2,3,5,6-tetrachlorophenyl sulfinic acid (15%). No metabolites were detected in the feces of monkeys dosed with 1,2,4,5-TeCB. While the fecal route represented the major route of excretion for 1,2,3,4-TeCB, the other two isomers were eliminated exclusively in the feces. The above data in the squirrel monkey are different from those obtained with the rat and the rabbit, and demonstrate the different metabolic pathways for the isomers.  相似文献   

7.
8.
1,2- and 1,3-glyceryl dinitrates (1,2-GDN and 1,3-GDN) are the primary metabolites of glyceryl trinitrate, a commonly used anti-anginal agent. The goal of this study was to examine the pharmacokinetic properties of these metabolites in rats. Sprague-Dawley rats were infused intravenously with 0.25 or 2.0 micrograms min-1 of either 1,2- or 1,3-GDN for 70 min, during which steady state blood concentrations were achieved. Post-infusion blood samples were collected for 30 min. 1,2-GDN was found to possess slightly higher clearance (32.3 vs 20.8 ml min-1 kg-1) and volume of distribution (695 vs 454 ml kg-1) than 1,3-GDN; however, the two metabolites exhibited similar mean residence times (22.0 vs 21.8 min). Upon an 8-fold increase in the infusion rate, the pharmacokinetic parameters were not significantly altered for either 1,2- or 1,3-GDN. When each GDN was co-infused with an 8-fold higher dose of the other GDN, there were also no significant changes in the parameters.  相似文献   

9.
10.
We previously reported on the inhibition of microtubule polymerization and the formation of ribbon structures by synthetic estrogens [Sato et al., J Biochem 101: 1247-1252, 1987]. The present investigation aimed to analyse these effects in vitro on stereochemical point of view, using hexestrol isomers ((R,R)-(+)-hexestrol, (S,S)-(-)-hexestrol and meso-hexestrol) and dl-hexestrol. Among hexestrols, dl-hexestrol showed the highest activity in ribbon formation from microtubule proteins at 100 microM. On the other hand, meso-hexestrol was distinguished from others by inhibition of microtubule assembly and formation of a large amount of aggregates from purified tubulin in the presence of MgCl2 and DMSO. These results were discussed with physico-chemical properties of hexestrols, e.g. absolute configurations as well as circular dichroism spectra and solid state carbon-13 nuclear magnetic resonance spectra.  相似文献   

11.
Staplabin and SMTPs, triprenyl phenol metabolites of the fungus Stachybotrys microspora, are a family of non-lysine-analog plasminogen modulators that enhance both activation and fibrin binding of plasminogen by modulating plasminogen conformation. These compounds, including SMTP-4, -5, -6, -7 and -8, have an amino acid or an amino alcohol moiety in their structure, and precursor amine feeding greatly increases the biosynthesis of a metabolite of interest. In the present study, we have isolated five novel SMTPs (designated SMTP-4D, -5D, -6D, -7D and -8D) from precursor D-amino acid-fed cultures. Physico-chemical properties as well as chromatographic behavior were distinct from those of the corresponding L-amino acid analogs, which are selectively accumulated in L-amino acid-fed cultures and share common properties with corresponding natural products. The D-series SMTPs enhanced urokinase-catalyzed plasminogen activation by 10-fold at 80 approximately 180 microM.  相似文献   

12.
13.
Over two hundred 1-, 3-, 8-, and 9-substituted-9-deazaxanthines were prepared and evaluated for their binding affinity at the recombinant human adenosine receptors, in particular at the hA(2B) and hA(2A) subtypes. Several ligands endowed with sub-micromolar to low nanomolar binding affinity at hA(2B) receptors, good selectivity over hA(2A) and hA(3), but a relatively poor selectivity over hA(1) were obtained. Good antagonistic potencies and efficacies, with pA(2) values close to the corresponding pK(i)s, were observed in functional assays in vitro performed on a selected series of compounds. 1,3-Dimethyl-8-phenoxy-(N-p-halogenophenyl)-acetamido-9-deazaxanthine derivatives appeared as the most interesting leads, some of them showing outstanding hA(2B) affinities, high selectivity over hA(2A) and hA(3), but low selectivity over hA(1). Structure-affinity relationships suggested that the binding potency at the hA(2B) receptor was mainly modulated by the steric (lipophilic) properties of the substituents at positions 1 and 3 and by the electronic and lipophilic characteristics of the substituents at position 8. A comparison among affinity and selectivity profiles of 9-deazaxanthines with the corresponding xanthines suggested some possible differences in their binding mode.  相似文献   

14.
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16.
1. The effects of (+/-)- (+)- and (-)-metoprolol, (+/-)- (+)- and (-)-pindolol, (+/-)-mepindolol and (+/-)-bopindolol on the beta 1-adrenoceptor mediated responses of the rat left atria and the beta 2-adrenoceptor mediated responses of the rat portal vein to isoprenaline have been determined. 2. Racemic and (-)-metoprolol were selective beta 1-adrenoceptor antagonists. (+)-Metoprolol was devoid of beta-adrenoceptor antagonistic activity. 3. Racemic and (-)-pindolol were potent and (+)-pindolol was a modest beta-adrenoceptor antagonist. 4. (+/-)-Mepindolol and (+/-)-bopindolol were apparently competitive antagonists of the isoprenaline beta 1-adrenoceptor mediated responses of the rat left atria but non-competitive antagonists of the isoprenaline beta 2-adrenoceptor mediated responses of the rat portal vein. 5. It is suggested that (+/-)-mepindolol and (+/-)-bopindolol are slowly dissociating beta-adrenoceptor antagonists and the non-competitive antagonism can only be detected on tissues with modest receptor reserves for maximum responses to isoprenaline.  相似文献   

17.
The synthesis and resolution of (+/-)-3-methoxycyproheptadine [(+/-)-4] are described. As a peripheral serotonin antagonist, (+/-)-4 was found to be one-half as potent as cyproheptadine (1b). The peripheral anticholinergic and antihistaminic activities as well as the orexigenic property of (+/-)-4 are less than those of 1b. A further comparison of the enantiomers (+)-4 and (-)-4 shows that all of the anticholinergic activity of (+/-)-4 resides solely in the dextrorotatory enantiomer, (+)-4, while the antiserotonin activity, which is similar to that of 1b, resides in the levorotatory enantiomer, (-)-4. Antihistaminic and orexigenic activity also resides in (-)-4 but these properties are reduced compared to those of 1b.  相似文献   

18.
19.
The effects of the ergolene derivatives bromocriptine, dihydroergotoxine, methysergide, d-LSD, CF 25-397, and 29-712 on the metabolism of the biogenic amines in the brain of the rat were investigated.All six ergolene derivatives were found to increase the concentration of 4-hydroxy-3-methoxyphenylethylene glycol sulphate in the brain stem, i.e., to increase the turnover of noradrenaline (NA). Since in brain homogenates the agents inhibited the binding of 3H-dihydroergocryptine to -adrenoceptors, but only weakly inhibited the binding of 3H-alprenolol to -adrenoceptors, it is suggested that the increased turnover of NA may be a consequence of a blockade of -adrenoceptors by ergolenes.All of the ergolenes increased the concentration of serotonin (5-HT) in the cortex, but only bromocriptine and 29-712 increased the concentration of 5-hydroxyindoleacetic acid (5-HIAA), the other compounds decreasing the concentration of this metabolite, i.e., inhibiting 5-HT turnover. Reserpine-induced PGO waves in the cat were inhibited by all six compounds, bromocriptine and 29-712 being the least active. Both of these findings suggest that the ergolenes possess serotonergic activity. The increase in the concentration of 5-HIAA after bromocriptine and 29-712 may be secondary to some action on other systems.The actions of the ergolenes on the metabolism of dopamine (DA) in the striatum are more complex. Bromocriptine, 29-712, and, to a much lesser extent, dihydroergotoxine reduced the concentration of 3,4-dihydroxyphenylacetic acid (DOPAC), i.e., they inhibited DA turnover. These findings are compatible with the proposed dopaminergic activity of the drugs. CF 25-397 caused a slight increase in the DOPAC concentration at high doses, and d-LSD and methysergide caused pronounced increases. At doses below 1 mg/kg i.p., d-LSD decreased the DOPAC concentration. This biphasic effect of d-LSD may be due to interaction with different types of DA receptors or may reflect some secondary action of the compound.The profiles of activity of the various ergolenes are discussed. Bromocriptine and 29-712, wich have similar profiles of activity, can be clearly differentiated from the other ergolenes. CF 25-397 seems to be a potent and, at low doses, specific serotonergic drug.  相似文献   

20.
N-Acetyl-L-cysteine was reacted with 2-(2-, 3-, or 4-methylphenyl)-oxiranes to give mixtures of the two possible regio isomers N-acetyl-S-[1-(2-, 3-, or 4-methylphenyl)-2-hydroxyethyl]-L-cysteine and N-acetyl-S-[2-(2-, 3-, or 4-methylphenyl)-2-hydroxyethyl]-L-cysteine, respectively. These were isolated in pure form by h.p.l.c.. The diastereomers were characterized by n.m.r. and mass spectrometry. The 2-, 3- and 4-ethenyl-methylbenzenes and the 2-(2-, 3-, and 4-methylphenyl)-oxiranes were injected i.p. into rats. G.l.c.-mass spectrometry showed similar patterns of acidic metabolites in the urine. Comparison with authentic mass spectra showed that the N-acetyl-S-[1-(methylphenyl)-2-hydroxyethyl]-L-cysteines accounted for over 80% of the mercapturic acids.  相似文献   

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