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Effect of formulation variables on the percutaneous permeation of ketoprofen from gel formulations.

The objectives of our study were to evaluate the effect of four terpene enhancers, enhancer lipophilicity, and ethanol concentration using hydroxypropyl cellulose (HPC) and two Pluronic F-127 (PF-127) gel formulations on the percutaneous permeation of ketoprofen. All experiments were conducted using hairless mouse skin in vitro. Data recorded over 24 hr was compared with that for control gels (containing no terpene) using Franz diffusion cells. In the three gel formulations, the highest increase in the ketoprofen permeation was observed using limonene followed by nerolidol, fenchone, and thymol. Relationships were established between terpene lipophilicity, enhancement ratios for ketoprofen flux (ERflux), and the cumulative amount of ketoprofen after 24 hr (Q24) from the three gel formulations. However, no correlation was established between terpene lipophilicity and ketoprofen skin content values at 24 hr. Ethanol had a synergistic effect on the enhancing activity of the terpenes. Increasing the concentration of ethanol from 10% to 50% was associated with an increase in the permeation of ketoprofen. For example, use of PF-127 gel control (no terpene was included) containing 10% ethanol resulted in a ketoprofen flux of 19 +/- 2 microg/cm2 h and 481 +/- 131 microg/cm2 for Q24. Furthermore, for PF-127 containing 33% ethanol the flux was 34 +/- 3 microg/cm2 h and Q24 was 1,420 +/- 111 microg/cm2. However, HPC gel control that contained 50% ethanol resulted in a ketoprofen flux of 67 +/- 6 microg/cm2 h and 2,839 +/- 222 microg/cm2 for Q24.

Administration, Cutaneous↗

Biological significance of essential oil of Zataria multiflora boiss.

The absolute from Zataria multiflora was explored for enzyme inhibition, insect repellent, and insecticidal activities. GC-MS of the absolute of fresh plant showed that thymol is the major constituent while carvacrol is the major constituent in the absolute of dried plant.

Animals↗

Analysis of essential oil of Satureja thymbra by hydrodistillation, thermal desorber, and headspace GC/MS techniques and its antimicrobial activity.

The essential oil composition of Satureja thymbra was analyzed by direct thermal desorber and Headspace GC/MS analysis methods. Its constituents were determined to be mainly carvacrol (40.15%), gamma-terpinene (26.56%), p-cymene (16.39%), and thymol (13.16%). The other techniques, thermal desorber and Headspace GC/MS, were used for the plant leaves at three different temperature, which showed similar results. The thermal desorber GC/MS gave better and more sensitive results than Headspace GC/MS. The essential oil was found to be active against the bacteria Escherichia coli, Pseudomonas aeruginosa, Salmonella typhimurium, Shigella sonnei, and Staphylococcus aureus and the yeast Candida albicans.

Bacteria↗

Solid phase microextraction with gas chromatography-mass spectrometry: a very rapid method for identification of volatile organic compounds emitted by Carum copticum.

The investigation of flower scent represents an important field of modern biological research which is directed towards special theories of biological recognition. The headspace solid phase microextraction coupled with gas chromatography-mass spectrometry was used to identify the volatile components of Carum copticum (C. copticum) cultivated in Iran. The compounds were identified according to their retention indices and mass spectra (EI, 70 eV). The effects of different parameters, such as the desorption time, the extraction temperature, the sample mass, the addition of salt, the pre-equilibration time and the extraction time, on the extraction efficiency were investigated. The optimized conditions were: the desorption time, 2 min; the extraction temperature, 58 degrees Celsius; the sample mass, 1.000 g in 4.0 mL 2.0 M NaCl solution; the pre-equilibration time, 25 min; the extraction time, 20 min. Finally, ten components were identified in the volatile components of C. copticum. The major components of C. copticum were thymol (68.2%), gamma-terpinene (13.9%), p-cymene (11.6%), myrcene (1.0%) and beta-pinene (0.6%). Precision of the proposed method is good and %RSD less than 14 was obtained.

Carum↗

Effects of dantrolene on steps of excitation-contraction coupling in mammalian skeletal muscle fibers.

The effects of the muscle relaxant dantrolene on steps of excitation-contraction coupling were studied on fast twitch muscles of rodents. To identify the site of action of the drug, single fibers for voltage-clamp measurements, heavy SR vesicles for calcium efflux studies and solubilized SR calcium release channels/RYRs for lipid bilayer studies were isolated. Using the double Vaseline-gap or the silicone-clamp technique, dantrolene was found to suppress the depolarization-induced elevation in intracellular calcium concentration ([Ca2+]i) by inhibiting the release of calcium from the SR. The suppression of [Ca2+]i was dose-dependent, with no effect at or below 1 microM and a 53 +/- 8% (mean +/- SEM, n = 9, cut fibers) attenuation at 0 mV with 25 microM of extracellularly applied dantrolene. The drug was not found to be more effective if injected than if applied extracellularly. Calculating the SR calcium release revealed an equal suppression of the steady (53 +/- 8%) and of the early peak component (46 +/- 6%). The drug did not interfere with the activation of the voltage sensor in as much as the voltage dependence of both intramembrane charge movements and the L-type calcium currents (I(Ca)) were left, essentially, unaltered. However, the inactivation of I(Ca) was slowed fourfold, and the conductance was reduced from 200 +/- 16 to 143 +/- 8 SF(-1) (n = 10). Dantrolene was found to inhibit thymol-stimulated calcium efflux from heavy SR vesicles by 44 +/- 10% (n = 3) at 12 microM. On the other hand, dantrolene failed to affect the isolated RYR incorporated into lipid bilayers. The channel displayed a constant open probability for as long as 30-50 min after the application of the drug. These data locate the binding site for dantrolene to be on the SR membrane, but be distinct from the purified RYR itself.

Animals↗

Effective treatment of experimental acute otitis media by application of volatile fluids into the ear canal.

Essential oils are volatile and can have good antimicrobial activity. We compared the effects of oil of basil (Ocimum basilicum) and essential oil components (thymol, carvacrol, and salicylaldehyde) to those of a placebo when placed in the ear canal of rats with experimental acute otitis media caused by pneumococci or Haemophilus influenzae. Progress was monitored by otomicroscopic examination and middle ear cultures. The treatment with oil of basil or essential oil components cured or healed 56%-81% of rats infected with H. influenzae and 6%-75% of rats infected with pneumococci, compared with 5.6%-6% of rats in the placebo group. Essential oils or their components placed in the ear canal can provide effective treatment of acute otitis media.

Acute Disease↗

Potential use of tea extract as a complementary mouthwash: comparative evaluation of two commercial samples.

OBJECTIVE: To evaluate the potential of using tea extracts as complementary mouthwash and to test the comparative efficacy of two commercial samples. DESIGN: A randomized controlled trial with 30 healthy human volunteers was carried out. The subjects were randomly assigned to 5 groups of 6 subjects per group. The ability of Ndu tea (from Cameroon) and Lipton tea (from Nigeria) to reduce colony forming units (CFU) in the liquid expectorated after 60 seconds of gargling from the mouth of the volunteers at 5 and 60 minutes were evaluated. These were compared to the values obtained from bank water and Minty Brett (thymol 0.047%), a standard antiseptic. SETTING: University of Nigeria, Nsukka, Enugu State, Nigeria. SUBJECTS: Thirty healthy human volunteers (18 males and 12 females, between 22-30 years of age) who met the eligibility requirement of being nonsmokers and not taking any other antimicrobial agent were selected for the study. RESULT: Relative to the bank water, the results indicated that the hot water extract of both teas significantly (p < 0.05) reduced CFU per milliliter in the liquid expectorated after gargling at both 5 and 60 minutes. Minty Brett showed higher activity than both tea extracts; however, unlike Minty Brett both extracts still reduced the CFU per milliliter at time 60 minutes (an indication of longer duration of activity). The combination of the tea extracts with sodium lauryl sulfate (1.2% w/v), a surfactant and emulsifier, significantly increased the antimicrobial activity relative to each tea alone. Comparatively, the activity of Ndu tea was found to be slightly higher than that of Lipton tea but this was not significant (p < 0.05). CONCLUSION: Lipton and Ndu tea extracts potently reduced the CFU per milliliter. This activity was potentiated by sodium lauryl sulfate. Although Minty Brett had more potent antimicrobial activity, both tea extracts have longer duration of activity. The results indicate the potential usefulness of tea extracts as a complementary mouthwash.

Adult↗

Amino acid sequence, post-translational modifications, binding and labelling of porcine odorant-binding protein.

An odorant-binding protein, migrating in SDS-PAGE with an apparent molecular weight of 22 kDa and an isoelectric point of 4.2, has been purified from pig nasal mucosa. Its complete amino acid sequence was determined by a combination of mass spectrometry and Edman degradation procedures. The protein consists of a single polypeptide chain of 157 amino acids, presenting at the N-terminus a pyroglutamic acid residue. The two cysteine residues, occurring in the primary structure at positions 63 and 155, are involved in an intramolecular disulphide bridge. Sequence comparison with other lipocalins revealed a good similarity with bovine odorant-binding protein, the only member of this class which does not contain disulphide bonds and of which the three-dimensional structure recently has been resolved. Nine out of the 1 6 residues lining the binding pocket in bovine OBP are conserved in the porcine protein, suggesting structural similarities in this region of the molecule. The synthesis of a fluorescent photoaffinity labelling agent and of two tin-containing thymol analogues is also described. These compounds together with other ligands were able to bind the protein as revealed by competitive binding experiments.

Amino Acid Sequence↗

Pseudomonas aeruginosa cells adapted to benzalkonium chloride show resistance to other membrane-active agents but not to clinically relevant antibiotics.

Our objective was to determine whether strains of Pseudomonas aeruginosa can adapt to growth in increasing concentrations of the disinfectant benzalkonium chloride (BKC), and whether co-resistance to clinically relevant antimicrobial agents occurs. Attempts were made to determine what phenotypic alterations accompanied resistance and whether these explained the mechanism of resistance. Strains were serially passaged in increasing concentrations of BKC in static nutrient broth cultures. Serotyping and genotyping were used to determine purity of the cultures. Two strains were examined for cross-resistance to other disinfectants and antibiotics by broth dilution MIC determination. Alterations in outer membrane proteins and lipopolysaccharide (LPS) expressed were examined by SDS-PAGE. Cell surface hydrophobicity and charge, uptake of disinfectant and proportion of specific fatty acid content of outer and cytoplasmic membranes were determined. Two P. aeruginosa strains showed a stable increase in resistance to BKC. Co-resistance to other quaternary ammonium compounds was observed in both strains; chloramphenicol and polymyxin B resistance were observed in one and a reduction in resistance to tobramycin observed in the other. However, no increased resistance to other biocides (chlorhexidine, triclosan, thymol) or antibiotics (ceftazidime, imipenem, ciprofloxacin, tobramycin) was detected. Characteristics accompanying resistance included alterations in outer membrane proteins, uptake of BKC, cell surface charge and hydrophobicity, and fatty acid content of the cytoplasmic membrane, although no evidence was found for alterations in LPS. Each of the two strains had different alterations in phenotype, indicating that such adaptation is unique to each strain of P. aeruginosa and does not result from a single mechanism shared by the whole species.

Anti-Bacterial Agents↗

Isoprenoids suppress the growth of murine B16 melanomas in vitro and in vivo.

Sundry mevalonate-derived constituents (isoprenoids) of fruits, vegetables and cereal grains suppress the growth of tumors. This study estimated the concentrations of structurally diverse isoprenoids required to inhibit the increase in a population of murine B16(F10) melanoma cells during a 48-h incubation by 50% (IC50 value). The IC50 values for d-limonene and perillyl alcohol, the monoterpenes in Phase I trials, were 450 and 250 micromol/L, respectively; related cyclic monoterpenes (perillaldehyde, carvacrol and thymol), an acyclic monoterpene (geraniol) and the end ring analog of beta-carotene (beta-ionone) had IC50 values in the range of 120-150 micromol/L. The IC50 value estimated for farnesol, the side-chain analog of the tocotrienols (50 micromol/L) fell midway between that of alpha-tocotrienol (110 micromol/L) and those estimated for gamma- (20 micromol/L) and delta- (10 micromol/L) tocotrienol. A novel tocotrienol lacking methyl groups on the tocol ring proved to be extremely potent (IC50, 0.9 micromol/L). In the first of two diet studies, experimental diets were fed to weanling C57BL female mice for 10 d prior to and 28 d following the implantation of the aggressively growing and highly metastatic B16(F10) melanoma. The isomolar (116 micromol/kg diet) and the Vitamin E-equivalent (928 micromol/kg diet) substitution of d-gamma-tocotrienol for dl-alpha-tocopherol in the AIN-76A diet produced 36 and 50% retardations, respectively, in tumor growth (P < 0.05). In the second study, melanomas were established before mice were fed experimental diets formulated with 2 mmol/kg d-gamma-tocotrienol, beta-ionone individually and in combination. Each treatment increased (P < 0.03) the duration of host survival. Our finding that the effects of individual isoprenoids were additive suggests the possibility that one component of the anticarcinogenic action of plant-based diets is the tumor growth-suppressive action of the diverse isoprenoid constituents of fruits, vegetables and cereal grains.

Animals↗

Construction of a multilayer planar membrane applicable to ion-transport measurement.

Multilayer planar membranes applicable to ion-transport measurements were constructed from egg yolk lecithin, egg yolk lecithin-cholesterol mixture, and 1,2-dipalmitoyl-sn-glycero-3-phosphocholine between two tightly stretched cellulose sheets. While most of the phospholipids in the membranes were found by a spin label technique to be uniformly oriented with their long hydrocarbon chains perpendicular to the surfaces of the cellulose sheets, a small fraction of phospholipids were isotropically oriented in multilayer membranes. The amount of phospholipids with isotropic orientations decreased with increasing content of cholesterol in membranes and became zero in membranes of egg yolk lecithin-cholesterol mixture (molar ratio of 1: 0.67). The degree of orientation, S, of uniformly oriented phospholipids in membranes was also increased by adding cholesterol to the membranes. The orientation of phospholipids in membranes was rather stable in distilled water and in aqueous calcium chloride (1, 10, 100 mM), while a marked disordering of oriented phospholipids was induced in a aqueous solutions containing thymol, isopropanol, or butanol beyond certain specific concentrations. The membranes can be used for measurements of calcium permeation. An appreciable barrier function to calcium permeation was detected with these multilayer planar membranes as compared with control experiments using only cellulose sheets as membranes. A preliminary investigation suggested that changes in the orientational structure of phospholipids in the multilayer planar membranes are correlated with permeability properties of the membranes.

Biological Transport↗

Permeability properties of a multilayer planar membrane.

The permeability properties of multilayer planar membranes of uniformly oriented lipids between a pair of cellulose sheets were investigated. The effect of the two cellulose sheets supporting the lipid membrane on the glucose or the Ca permeation was subtracted empirically, and values of 5 X 10(-6) and 8 X 10(-6) cm/s were thus obtained for the permeability coefficients of an egg yolk lecithin (egg PC)-cholesterol membrane of about 200 bilayers to Ca2+ and glucose, respectively. These values are discussed as compared with the permeability coefficients of other model membranes. The membrane permeability was moderately affected by the addition of chemical substances to egg PC membranes. It was reduced by the presence of cholesterol, but enhanced by the presence of isopropanol, n-butanol, or thymol in the same solution above a critical concentration of each compound. These and previous observations (8) suggest that a close correlation may exist between the permeability of the membrane and the orientation of the membrane lipids. The glucose permeation was drastically suppressed by the presence of Ca2+ (10 mM) in the sample solution with the membrane containing phosphatidylserine, but was not at all suppressed with the membrane of the egg PC-cholesterol mixture.

1-Propanol↗

Binding of halothane to serum albumin demonstrated using tryptophan fluorescence.

BACKGROUND: The site of action of general anesthesia remains controversial, but evidence in favor of specific protein target(s) is accumulating. Saturable binding of halothane to bovine serum albumin (BSA) has recently been reported using photoaffinity labeling and fluorine 19 nuclear magnetic resonance spectroscopy. We report a new approach to study anesthetic binding to soluble proteins, based on native tryptophan fluorescence. METHODS: Thymol-free halothane and fatty acid-free BSA were equilibrated in gas-tight Hamilton syringes and dispensed into stoppered quartz cuvettes at predetermined dilutions. Steady-state fluorescence spectroscopy was used to study their interaction. RESULTS: Halothane quenched the tryptophan fluorescence of BSA in a concentration-dependent, saturable manner with a dissociation constant = 1.8 +/- 0.2 mM and a Hill number = 1.0 +/- 0.1. The two optical isomers of halothane bound to BSA with equal affinity. The ability of halothane to quench BSA tryptophan fluorescence was markedly decreased at pH 3.0 (which causes full uncoiling of BSA), with loss of saturable binding. Diethyl ether displaced a portion of halothane from its binding sites. Circular dichroism spectroscopy revealed no significant effect of halothane or diethyl ether on the secondary structure of BSA. CONCLUSIONS: The results suggest that halothane binds in hydrophobic domains containing tryptophan in BSA. This approach may prove useful for studying the interaction of volatile anesthetics and proteins and has the advantage that the location of halothane in the protein is identified.

Fluorescence↗

Intrahepatic cholangiocarcinomas associated with nonbiliary cirrhosis. A clinicopathologic study.

To determine the prevalence and clinicopathologic features of cholangiocarcinoma (CC) associated with nonbiliary cirrhosis, we performed a clinicopathologic study. Among the 5,563 autopsies in our laboratories during the past 14 years, 85 (1.5%) were CCs. Four (4.7%) were associated with cirrhosis, due to hepatitis B virus in one case and cryptogenic (probably non-A non-B hepatitis virus) in the remaining three. Clinically, patients with CC and cirrhosis were characterized by male preponderance, lower age, past history of liver injury, and elevated values of zinc sulfate and thymol turbidity tests. Pathologically, all CCs with cirrhosis were basically adenocarcinoma; other histologic features included adenocarcinoma resembling bile ductules without mucin (one case), adenocarcinoma with broad areas of signet ring cell carcinoma (one case), adenocarcinoma with extensive sarcomatoid transformation (one case), and adenocarcinoma associated with hepatoliths (one case). Immunohistochemically, immunophenotypes of carcinoma cells of CC with cirrhosis were not different from those of CC without cirrhosis. Carcinoembryonic antigens, CA19-9, DU-PAN-2, and biliary-type cytokeratins were positive and alpha-fetoprotein was negative, suggesting that our CCs are not hepatocellular neoplasms but true CCs. It must be stressed that there are actual CCs arising in nonbiliary cirrhotic livers.

Adenocarcinoma↗

Hemochromatosis associated with brain lesions--a disorder of trace-metal binding proteins and/or polymers?

A 68-year-old man, after having been diagnosed as having hepatic disease at about the age of 41 years, had been hospitalized frequently until his death. Blood sugar, iron, and copper had not increased during his illness. Although the diagnosis of liver cirrhosis had been made and he had been receiving therapy, various neurologic symptoms without disturbances of consciousness appeared six months before his death. Autopsy revealed hemochromatosis, liver cirrhosis, and pancreatic fibrosis. A large amount of iron had accumulated in the liver, the pancreas, and the thyroid gland, while considerable numbers of ceroid and lipofuscin pigment granules had accumulated diffusely in the brain. Abnormal astrocytes of the Alzheimer II type were diffusely distributed in the brain and contained no intranuclear glycogen which stained positive with the carmine stain. No spongy changes were seen in the deeper layers of the cerebral cortex. Chemical analyses for trace metals in the brain, liver, and kidneys revealed a large amount of iron and increased copper in the liver, and considerable quantities of copper, manganese, calcium, and mercury in the brain. Because of changes in the erythrocyte sedimentation rate and marked thymol turbidity seen before and after the occurrence of the neurologic symptoms, this man was suspected of having disorders of the trace-metal binding proteins and/or of their polymers.

Aged↗

Isolation and purification of leaf starch components.

A procedure was developed for the separation and purification of amylose and amylopectin isolated from cotton leaves. Cotton leaves were homogenized in 0.02 molar phosphate buffer at pH 7.0 containing HgCl(2) plus toluene. Crude starch granules were collected by centrifugation and partially purified by treating with acetone and toluene. The starch granules were then dispersed in dimethylsulfoxide and precipitated with ethyl alcohol. The precipitate was suspended in boiling water. Amylose was separated from amylopectin and cell wall particles on a Sepharose 2B column and further purified with thymol and butanol. Amylopectin was then separated from the colloidal cell wall contaminants by its specific interaction with concanavalin A. Purities of starch components were verified by specific biochemical and enzymic tests in addition to their iodine-binding capacity. This procedure should also be suitable for purification of starch components from other plant sources.

Journal Article↗

Comparative evaluation on mouse nasal immunogenicity of arylmethane-, xanthene-, quinone-imine-, and acridine-dye-inactivated Sendai virus vaccines.

Twenty-seven kinds of organic dye-inactivated Sendai virus vaccines were prepared by treatment in dark at 23 C for 2 months or more, and selected with the high HA titers as a guide. Their nasal immunogenicities were examined in mice by contact infection and immunofluorescent method, and the relative merits of the dye-inactivants were determined. The strongest protection was elicited with acriflavine-, auramine O-, eosin Y-, neutral red-, night blue-, patent blue V-, thymol blue-, uranin-, and xylene cyanol FF-treated vaccines. Middling protective efficacy was induced by use of erio green B-, malachite green-, methyl green-, proflavine-, pyronin B-, and thionin-inactivated vaccines. Dye-inactivated vaccines that resulted in the weakest protection were Bindschedler's green-, bromothymol blue-, erythrosin B-, ethyl violet-, gallein-, light green SF yellowish-, methyl violet-, new methylene blue N-, phenol red-, rhodamine 6G-, spirit blue- and victoria blue B-treated ones. Serum HI titers developed by nasal vaccination were variable, and rose still more in most vaccinated groups postexposure. Elicitation of the most effective nasal immunogenicity in dye-inactivated vaccines appeared to depend on selective modification of capsid protein or ribose in viral core with dyes possessing definite functions, despite the different molecular structures.

Animals↗

Topical tretinoin: a new treatment for black hairy tongue (lingua villosa nigra).

Black hairy tongue is the name given to the appearance of an abnormal coating of the tongue and occurs only in adults. It is the result of hyperkeratosis of the filiform lingual papillae which, on gross examination appear hair-like with a variable tinctorial aspect from yellow-brown to black. The pathogenesis is unknown and often no definite cause can be identified. A number of aetiologic factors have been implicated including the administration of topical or systemic antibiotics, poor oral hygiene, smoking, alcohol and the use of mouthwashes. Often there are no symptoms other than the aesthetic or anxiety over its aetiology. Some patients complain of gagging, nausea, alteration of taste or halitosis. The condition may be very persistent and recognized treatments include brushing with a soft tooth brush which is enhanced by the prior application of a 40% solution of urea, scraping, topical triamcinolone acetonide, gentian violet, thymol, salicylic acid, vitamin B complex, and surgical excision of the papillae.

Administration, Topical↗