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Camphor and m-cresol mixtures are used in antiseptic and anti-itching creams. No compendial method exists for these preparations. This paper reports a capillary gas chromatographic method using FID detection with 2,6-di-tert-butyl-4-methylphenol as internal standard on a 30 m×0.32 mm Supelcowax®-10 column (0.25 μm film) with helium as carrier gas. Ramped temperature programming was applied. The method allows simultaneous quantitation of camphor and m-cresol in the presence of o- and p-cresols, calamine and zinc oxide. Overall percent recoveries (±SD, n=9) of camphor, o-, p- and m-cresol from spiked placebo creams, at a labeled amount of 10 (w/w)% were 96.9±0.6, 98.2±0.6, 99.2±0.5 and 101.0±0.9%, respectively, and at a labeled amount of 1% were 96.7±0.6, 97.8±0.9, 97.8±0.6, and 100.3±1.0%, respectively. The recovery studies were carried out at ±30% of the labeled amounts. Linear peak area or height ratios were obtained (r>0.999) for camphor, o-, p- and m-cresol covering a concentration range of 10–200% of the labeled amount. Linearity (r>0.999) was also obtained for m-cresol when the relative concentration of o- and p-cresol was varied from 5 to 100% of the m-cresol concentration. The resolution between the ‘critical pair’ of p- and m-cresol was ≥1.1. The limit of quantitation was 23 pg for m-cresol and 9.3 pg for camphor using an injection split of 1:50. The repeatability (%RSD) for all compounds were <2% for peak area and <1.4% for peak height ratios. System suitability and robustness of the method were established. The method was successively applied to the assay of available commercial products and allows assay of camphor and the three cresol isomers.  相似文献   
3.
Abstract Short-chain carboxylic acids (SCCA; C≤5: e.g., lactic acid, propionic acid, butyric acid) are metabolic by-products of bacterial metabolism which accumulate in the gingival crevice, and exhibit significant biological activity, including the ability to alter gene expression. It has been hypothesized that among the activities of SCCAs are their ability to contribute to gingival inflammation. This concept complements the notion that specific periodontal pathogens are the causative agents of gingival inflammation. To begin testing these 2 hypotheses, we examined the relationship between SCCA concentrations, specific putative periodontal pathogens, and gingival inflammation in medically healthy periodontally diseased subjects. We reasoned that if SCCAs and/or specific periodontal pathogens were causative gingival inflammatory agents, gingival inflammation should increase with increasing concentration of the inflammatory mediator. We also recognized that other clinical variables needed to be controlled for, and an objective quantitative assessment of gingival inflammation used. To accomplish these tasks, sites within subjects were stratified by location and pocket depth, and the following quantified: bacteria] presence; SCCA concentration: and gingival inflammation. The results indicated that gingival inflammation directly and significantly correlated with SCCA concentrations in the maxillary and mandibular molars, incisors and canines (all r≥0.47; all p≤ 0.015; too few bicuspids were available for complete analysis). The relationship between gingival inflammation and SCCA concentration was best described by a natural log relationship. Gingival inflammation did not, however, correlate positively with either the total number of specific putative periodontal pathogens, or the sum of subsets of these pathogens (?0.31 ≤r≤ 0.39; 0.08 ≤p 0.75) for any of the locations. Finally, the SCCA concentration did not correlate with the level of individual or groups of pathogens. These data, together with historical work and other preliminary data, support the hypothesis that SCCA, rather than specific putative periodontal pathogens, may be a causative agent in gingival inflammation. This work may, in part, begin to explain the apparent lack of a direct relationship between current gingival inflammation and the prediction of bacterially mediated periodontal attachment loss.  相似文献   
4.
本文建立了氢醌酯的薄层扫描测定方法。以甲苯:乙醚(4:1)为展开剂,氢氧化钠的醇溶液浸渍显色,λ_R=620nm,λ_?=375nm,对氢醌酯的含量进行了双波长薄层扫描法测定,结果回收率99.5%,CV=1.2%,表明该法简单,可行。  相似文献   
5.
Cutaneous allergy to mustard in a salad maker   总被引:1,自引:0,他引:1  
A case of allergic contact dermatitis to mustard (Brassica nigra) in a salad maker is reported. The sources of skin contact included a commercial salad cream, a vinegrette, and various members of the mustard family, Cruciferae. The Cruciferae family includes many salad vegetables and condiments which contain allergenic isothiocyanates. The extent of skin contact among salad makers and other food handlers may be significant, and sensitization to isothiocyanates from this large family of vegetables may be an important cause of food contact allergy in these individuals.  相似文献   
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There is a growing need for research into new skin- and environment-friendly surfactants. This paper focuses on a natural surfactant of an alkylpolyglucoside type, which can form both thermotropic and lyotropic liquid-crystalline phases. The aim of this study was to relate some physicochemical properties (characterised by polarisation and transmission electron microscopy, thermal analysis and rheology) of the three formulations based on cetearyl glucoside and cetearyl alcohol, to the results of in vitro and in vivo bioavailability of hydrocortisone (HC). The three formulations contained oils of different polarity (medium chain triglycerides: MG, isopropyl myristate: IPM and light liquid paraffin: LP), respectively. In vitro permeation was followed through the artificial skin constructs (ASC), while the parameters measured in vivo were erythema index: EI (using instrumental human skin blanching assay), transepidermal water loss (TEWL) and stratum corneum hydration (SCH). The vehicles based on cetearyl glucoside and cetearyl alcohol showed a complex colloidal structure of lamellar liquid-crystalline and lamellar gel-crystalline type, depending on oil polarity. Rheological profile of the vehicle was directly related to the in vitro profile of the HC permeation. In vivo results suggested that the vehicle with MG retarded the HC permeation, whereas less polar IPM and non-polar LP enhanced it. It is suggested that the enhancement is achieved either by a direct interaction with lipid lamellae of the SC or indirectly by improving skin hydration.

There were no adverse effects during in vivo study, which indicates a good safety profile of this alkylpolyglucoside surfactant.  相似文献   

8.
陈雅  杨征  吴畏 《中国药业》2007,16(2):29-29
目的考察伊柔美白霜的祛斑功效。方法在家兔皮肤上涂抹补骨脂酊,待日光照射使皮肤上形成黄褐斑后,涂抹伊柔美白霜。结果涂抹伊柔美白霜20d后,黄褐斑有明显减退。结论伊柔美白霜具有脱色、增白的功效。  相似文献   
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10.
A double blind clinical trial was conducted with Egocort 1% Cream and plain aqueous cream applied to each half of the body in ten patients with eczema. The patients were assessed for erythema, papules, vesicles, scaling and pruritus at the beginning of treatment, after 7-14 days and again after a further 7-14 days.
The results show that Egocort 1% Cream is more effective in treating eczema than plain aqueous cream. The preparation was found pleasant to use and no side-effects were noted.  相似文献   
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