The thin-layer chromatography of 2,4-dinitrophenyl ethers of some hydroxy compounds.
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A simple and rapid isocratic HPLC assay is presented for the analysis and quantification of monoterpenes, i.e., carvone, cineole, perillaldehyde, perillyl alcohol and sobrerol in the diet of laboratory animals. The monoterpenes were extracted from the diet using 90% methanol in water. The analysis for the monoterpenes was performed by HPLC using a Whatman PartiSphere C18 column with UV detection. The mobile phase was isocratic methanol-water (72:28, v/v) for carvone, cineole, perillaldehyde and perillyl alcohol and methanol-water (65:35, v/v) for sobrerol. The method was simple with good repeatability (R.S.D. = 4.2-16.1%), reproducibility (R.S.D. = 3.7-19%), and accuracy (R.S.D. = 5.5-23.3%). The detection limit of the monoterpenes extracted from the diet was 2 micrograms/g for carvone, perillaldehyde and sobrerol, 20 micrograms/g for perillyl alcohol and 100 micrograms/g for cineole. Excellent resolution was achieved between the monoterpenes and the constituents of the diet. The method demonstrated applicability to monitoring the formulation of monoterpenes in the diet of laboratory animals.
PURPOSE: We review the physiology of bladder cooling response in experimental animals and humans, and present its clinical usefulness. MATERIALS AND METHODS: We describe experimental studies of the bladder cooling response, and more recent clinical retrospective and prospective studies of the bladder cooling test in adults and children. RESULTS: Studies indicate the existence of a segmental spinal bladder cooling reflex that originates from specific cold receptors in the bladder and urethral walls supplied by unmyelinated C-afferents. The reflex is positive in neurologically normal infants and children until about age 4 years. It becomes negative with further maturation of the nervous system but may be unmasked by pathological processes that disturb the descending neuronal control of normal voiding. A positive test in a patient with an overactive bladder requires further neurourological evaluation. CONCLUSIONS: The bladder cooling response originates from cold receptors within the walls of the lower urinary tract. The cooling response represents a neonatal reflex that may be unmasked by central neuropathology, analogous to the appearance of the Basbinki sign in pyramidal tract lesions. The bladder cooling test is a simple and valuable tool to support the diagnosis of neurourological disorders.
Mentha longifolia (Lamiaceae), an aromatic herb yielded a new halogenated chloro-derivative of menthone (longifone), two new derivatives of beta-sitosterol glycoside (longiside-A and -B) and a new flavanone-glycoside (longitin). The beta-sitosterol and flavanone glycosides were purified as their acetate derivatives. Structures of all the isolated constituents were elucidated with the aid of HMBC techniques. However, the structure of longifone was also determined through X-ray crystallography.
A new monoterpene-glycoside (2-exo-beta-D-glucopyranosyl-1,8-cineol) named bucharioside from the methanol-soluble part and a new sesquiterpenoid (4,10-epoxy-6alpha-hydroxyguaiane) named buchariol from the hexane-soluble part of Salvia bucharica were obtained. Their structures were elucidated with the help of NMR spectroscopy including 1D and 2D experiments.
Twenty distal roots of extracted mandibular first and second molars were instrumented, then obturated using Thermafil obturating material with solid plastic core carriers. To simulate a retreatment process, the gutta-percha was softened using one of four solvents, chloroform, xylene, eucalyptol, or halothane. A K file was used to advance the solvent into the gutta-percha and to engage the plastic carrier. In all but one case, the plastic carriers were easily removed from the root canal. It was concluded that the plastic carriers used with the Thermafil obturation media do not present a difficult obstacle for removal should the root require retreatment.
Because chloroform was identified as a potential carcinogen by the Food and Drug Administration, interest has been revived to identify an alternative solvent to soften gutta-percha for removal from obturated root canals. This study compared the effectiveness of halothane, eucalyptol, and chloroform in softening gutta-percha in simulated root canals. One milliliter of a solvent was placed into a small glass funnel whose stem was obturated with a 30-mm column of gutta-percha. After 30 s, softening was evaluated for each solvent by recording the time required to reach a depth of 10 mm by hand filing with a #100 Hedstrom file. The depth of penetration of a #40 finger plugger under constant weight for 15 min was also determined for each solvent. By using a one-way analysis of variance and Scheffe's test, all comparisons were not significant except for the depth of penetration with constant weight between chloroform and halothane (p less than 0.05). The results indicate that halothane and eucalyptol are suitable alternatives to chloroform as gutta-percha softening solvents.
Five solvents (rectified white turpentine, oil of melaleuca, eucalyptol, white pine oil, and pine needle oil) were compared with chloroform for their ability to dissolve gutta-percha. All solvents dissolved at least 50% of the gutta-percha in 15 min at 37 degrees C with chloroform and rectified white turpentine dissolving the gutta-percha completely.
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This study compared the apical seal produced by four obturation techniques. Sixty-four extracted human teeth were prepared and obturated using lateral condensation of gutta-percha that was either unmodified or was dipped in chloroform, eucalyptol, or eucapercha paste. After storage in normal saline and 0.02% azide solution at 37 degrees C for 200 days, the teeth were immersed in India ink for 48 h. The most coronal extent of leakage of India ink into the canal was then determined. Significantly more apical leakage occurred in the eucapercha group than in the other three groups. All other comparisons were equivalent. The results suggest that modification of the gutta-percha master cone with solvent does not improve the apical seal in vitro. If modification is desired, then dipping the master cone in either eucalyptol or chloroform produces an apical seal superior to that achieved with eucapercha.
Three groups of extracted teeth were obturated using gutta-percha and lateral condensation. In one group the gutta-percha was dipped in chloroform before condensation. In a second a eucalyptol dip was used. No dip was used in the third group. A dye penetration study was done to compare leakage among the three groups. The teeth were cleared for viewing and measurements of dye penetration were made using a stereomicroscope. Statistical analysis using Kruskal-Wallis one-way analysis of variance of the results showed no significant difference among test groups at the 0.05 level.
Eucalyptol and d-limonene were evaluated for their ability to serve as a substitute solvent for chloroform. The amount of time required to soften and remove the gutta-percha in 72 instrumented and filled simulated root canals in epoxy blocks was measured. After preparation to the apices of the block canals with a #60 file, four different filling techniques were used. These obturations were softened with each solvent and then removed, first using a #15 Hedstrom file inserted to full working length, and then removing the remaining filling mass with a #60 reamer. The two instrument placements were timed: one for the Hedstrom file insertion to the apex and the other for the reamer to remove the filling material. Neither the different solvents nor the filling techniques had a significant effect on the times required for the H-files to reach the apex. However, the times for the reamer to remove the filling materials were effected both by the filling techniques and the solvents used.
The essential oils of Caesulia axillaris and Mentha arvensis have been tested for their fumigant activity in the management of biodeterioration of stored wheat samples by Aspergillus flavus and the insect pests, Sitophilus oryzae and Tribolium castaneum, at 1300 and 600 ppm, respectively. The findings indicate the efficacy of the oils as potent fumigants for management of the biodeterioration of stored wheat samples. The oils also controlled the blue mould rot of oranges caused by Penicillium italicum and enhanced the market life of the oranges for a considerable period, showing their efficacy as postharvest fungicides of higher plant origin.
Xanthobacter sp. C20 was isolated from sediment of the river Rhine using cyclohexane as sole source of carbon and energy. Xanthobacter sp. C20 converted both enantiomers of limonene quantitatively into limonene-8,9-epoxide, a not previously described bioconversion product of limonene. With (4R)-limonene, (4R,8R)-limonene-8, 9-epoxide was formed as the only reaction product, while (4S)-limonene was converted into a (78:22) mixture of (4S,8R)- and (4S,8S)-limonene-8,9-epoxide. Cytochrome P-450 was shown to be induced concomitantly with limonene bioconversion activity following growth of Xanthobacter sp. C20 on cyclohexane. Maximal limonene bioconversion rate was observed at an initial substrate concentration of 12 mM. The amount of limonene-8,9-epoxide formed, up to 0.8 g l(-1), was limited by a strong product inhibition.
The effect of chemical penetration enhancers (e.g., eugenol, d-limonene and menthone in combination with 50% ethanol) on the in vitro percutaneous absorption of tamoxifen through porcine epidermis has been investigated. The above enhancers significantly increased (p<0.05) the permeability coefficient of tamoxifen in comparison with the control (50% ethanol). Fourier transform infrared spectroscopy (FT-IR) was employed to investigate the biophysical changes in the stratum corneum (SC) lipids by the enhancer(s). FT-IR results showed that the treatment of the SC with enhancers did not produce a blue shift in the asymmetric and symmetric C-H stretching peak positions. However, all of the above enhancers showed a decrease in peak heights and areas for both asymmetric and symmetric C-H stretching absorbances in comparison with the untreated SC. A decrease in peak heights and areas is a measure of lipid extraction. Partitioning of tamoxifen to powdered SC from control and enhancer solutions was also determined. FT-IR and partitioning studies reveal that the enhancement in the permeability coefficient of tamoxifen by eugenol and d-limonene is due to lipid extraction and improvement in the partitioning of the drug to the SC. However, menthone enhanced the permeability of tamoxifen by increasing extraction of the SC lipids and not by improving the partitioning of the drug to the SC.