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At least 19 recordsLinked to original sources
PubMed2004

Effects of mastic resin and its essential oil on the growth of proteolytic Clostridium botulinum.

Studies were done to determine the effect of mastic resin and its essential oil, alone and in conjunction with ethanol, on the growth of proteolytic strains of Clostridium botulinum in media, and on neurotoxin production in challenge studies with English-style crumpets. Preliminary studies, using a spot-on-the-lawn method, indicated that high levels of mastic resin in ethanol ( approximately 8% w/w) were required for complete inhibition of all strains of C. botulinum tested, but mastic resin in ethanol had a greater anti-botulinal effect than ethanol alone. However, only low levels of mastic oil ( approximately 0.3% v/v) were required for inhibition of proteolytic strains of C. botulinum. Both studies showed a strain specific inhibition, with C. botulinum type A strains being more sensitive to mastic resin and its essential oil than type B strains. However, mastic resin in ethanol proved to be more effective when used as a vapor phase inhibitor applied to cotton pads and placed inside inoculated plates than when added directly to media. While both mastic resin and its essential oil inhibited the growth of proteolytic strains of C. botulinum in vitro, they failed to inhibit neurotoxin production in challenge studies with C. botulinum in English-style crumpets.

Botulinum Toxins↗
PubMed2001

A mass spectrometry and electron paramagnetic resonance study of photochemical and thermal aging of triterpenoid varnishes.

Photochemical and thermal aging of triterpenoid dammar and mastic resins used as varnishes on paintings were studied using graphite-assisted laser desorption/ionization mass spectrometry. This extends an earlier study on similar materials (Zumbühl et al., Anal. Chem. 1998, 70, 707-715) that focused on photoaging. Progressive aging results in development of groups of signals spaced by 14 and 16 Da, indicating incorporation of oxygen as well as simultaneous loss of hydrogen. Oligomers up to tetramers are formed, while cleavage reactions lead to increased signal intensities in the mass ranges between the oligomers and below the monomers. No major differences were found between the mass spectra of samples aged in light or darkness, except that deterioration was faster in light. Electron paramagnetic resonance spectroscopy revealed similar and significant amounts of radicals in films of dammar stored either in light or in darkness. It is concluded that oxidative radical reactions also take place in darkness and that differences in light and dark aging pathways are minor, although rates may differ. These findings lead to a unified explanation for yellowing of natural resin varnishes, one of the major degenerative changes in the appearance of paintings. It is also shown that the commercially available, nominally fresh resins are already in an advanced stage of oxidation and degradation. Energy-rich substances are formed upon irradiation with sunlight and are believed to restart the autoxidative chain reactions, regardless of storage conditions. As a result, varnishes are oxidized quite quickly (months) even when kept in darkness.

Journal Article↗
PubMed2003

Direct-temperature mass spectrometric detection of volatile terpenoids and natural terpenoid polymersin fresh and artificially aged resins.

Electron impact (EI) ionization and ammonia chemical ionization (NH(3)/CI) direct-temperature mass spectrometry (DTMS) was used to characterize five natural terpenoid resins: dammar, mastic, colophony, Manila copal and sandarac. Compositional differences were highlighted by the identification of low molecular mass compounds, ranging from di- to triterpenoids, and polymeric components, based on polycadinene and polycommunic acid. Photo-ageing processes occurring under accelerated indoor and outdoor exposure conditions were also investigated. NH(3)/CI and tetramethylammonium hydroxide EI were applied to increase the sensitivity towards highly oxidized molecules. Oxidation and cross-linking reactions were found to affect mostly triterpenoid resins and diterpenoid abietane and pimarane molecules. Oxidation proceeds through a radical mechanism, generally starting from conjugated double bonds. Oxygen atoms are incorporated in the terpenoid structures in the form of alcohols, ketones and carboxylic acids. Oxidized cadinene oligomers released by pyrolytic degradation of the polycadinene fraction of dammar were detected even in unaged samples. Evidence is given indicating the occurrence of cleavages in the cross-linked polycommunic structure of aged sandarac and Manila copal. Bond scissions produce oligomeric fragments based on the communic acid structure and sufficiently volatile to be desorbed at low temperature in DTMS measurements.

Journal Article↗
PubMed2005

MALDI-TOF mass spectrometry on cellulosic surfaces of fresh and photo-aged di- and triterpenoid varnish resins.

Matrix-Assisted Laser Desorption/Ionization Time-of-Flight mass spectrometry (MALDI-TOF-MS) on cellulosic surfaces is shown to be a suitable method for examining highly oxidized terpenoids, which are otherwise too difficult to determine by other techniques. By crystallization of a 2,5-dihydroxybenzoic acid (DHB) matrix and the sample solution on cellulose-coated thin layer chromatography(TLC) plates, spectra with good signal/noise ratios are obtained and no significant interferences due to matrix ions or cluster ions were produced, at least not in the range of m/z values of interest (>300 Da). The validity of the method was tested on natural di- and triterpenoid resins used as paint varnishes by Old Masters. The samples were analyzed before and after artificial light ageing. Di- and triterpenoid compounds, being very sensitive towards photo-oxidation, were found as oxidized molecules even in the raw resins and in the unexposed varnish layers. Artificial ageing simulating window-filtered daylight resulted in a stronger oxidation of the original terpenoids and the incorporation of up to six oxygen atoms per molecule could be demonstrated. Terpenoid dimers and their oxidation products were also detected.

Cellulose↗
PubMed1994

The influence of tape type and of skin preparation on the force required to dislodge angiocatheters.

The study evaluated the effects of different techniques used to secure intravenous (i.v.) catheters. An angiocatheter attached to standard i.v. tubing was taped to human forearm using a standard taping method. A calibrated piezoelectric force transducer was attached to the i.v. tubing. The force applied along the longitudinal axis to pull out the taped catheter was measured and recorded on paper. Three tape types, Curity, Leukopor and Transpore, were evaluated alone, with benzoin skin pretreatment and with mastisol pretreatment. A randomized 3 x 3 block design with 20 replications per block was utilized, and a total of 180 pullout tests were performed on two adult volunteers. Without pretreatment, the forces required to dislodge catheters were (means +/- SEM) 46 +/- 2, 37 +/- 2 and 38 +/- 2 Newtons for Curity, Leukopor and Transpore tape, respectively. Corresponding values for mastisol pretreatment (64 +/- 1, 64 +/- 3 and 52 +/- 3 Newtons) were greater (P < 0.05) for each tape compared with benzoin (54 +/- 3, 53 +/- 2 and 40 +/- 2 Newtons) and no pretreatment. The most frequent failure mode for Transpore tape was by tape fracture, for Curity tape was by separation from the skin of tape and catheter as a single unit, and for Leukopor tape was by catheter separation while tape remained attached to skin (P < 0.001). The data suggest that the application of mastisol prior to taping i.v. catheters with Curity or Leukopor tape helps to minimize the risk of accidental dislodgement.

Adhesiveness↗
PubMed1986

Evaluation of mastic, a crude drug obtained from Pistacia lentiscus for gastric and duodenal anti-ulcer activity.

The effect of mastic, a concrete resinous exudate obtained from the stem of the tree Pistacia lentiscus, has been studied on experimentally-induced gastric and duodenal ulcers in rats. Mastic at an oral dose of 500 mg/kg produced a significant reduction in the intensity of gastric mucosal damage induced by pyloric ligation, aspirin, phenylbutazone, reserpine and restraint + cold stress. It produced a significant decrease of free acidity in 6-h pylorus-ligated rats and a marked cytoprotective effect against 50% ethanol in rats which could be reversed by prior treatment with indomethacin. The protective effect was not seen when it was given intraperitoneally in phenylbutazone and restraint + cold stress models. The reduction in the intensity of ulceration in cysteamine-induced duodenal ulcers was not found to be statistically significant in mastic-pretreated rats. The results suggest that mild antisecretory and a localized adaptive cytoprotectant action may be responsible for its anti-ulcer activity. These observations support the results of an earlier study on the clinical effectiveness of mastic in the therapy of duodenal ulcer.

Animals↗
PubMed2005

Reinforcement of subcuticular continuous suture closure with surgical adhesive strips and gum mastic: Is there any additional strength provided?

BACKGROUND: This study aimed to compare the burst strength of suture closure versus the use of suture and strip together. METHODS: On cadavers, 50 skin incisions were closed as follows: group 1--subcuticular continuous suture; group 2--same suturing with placement of strips; group 3--same as group 2 except gum mastic was applied prior to strips; group 4--strips alone; and group 5--strips with gum mastic application. The separation forces were measured using a tensilometer. RESULTS: The mean separation forces were as follows: group 1, 14.17 kg; group 2, 14.37 kg; group 3, 15.39 kg; group 4, 1.52 kg; and group 5, 3.85 kg. There were no statistically significant differences between groups 1, 2, and 3. When compared with group 4, group 5 required markedly more force to separate the wound. CONCLUSIONS: Strip reinforcement with/without gum mastic did not provide any additional strength when sutures were used. Gum mastic increased the adherence of strips and this was important when strips were the only means of wound closure.

Adult↗
PubMed2005

In vitro and in vivo antimicrobial effects of mastic chewing gum against Streptococcus mutans and mutans streptococci.

BACKGROUND AND OBJECTIVE: Dental caries is associated with oral pathogens and Streptococcus mutans (S. mutans) is one of the primary cariogenic organisms. Mastic gum, from Pistacia lentiscus, has been shown to have antibacterial properties. The objective of this study was to determine antibacterial activity of mastic chewing gum against S. mutans and mutans streptococci in vitro and in vivo conditions. SETTING: Cukurova University, Dental School, in 2002. MATERIALS AND METHODS: Antimicrobial activity of mastic gum was evaluated using standard S. mutans strain by disc diffusion method in vitro. Cytotoxicity effect of mastic gum on HEp-2 cells was evaluated by conventional haemocytometer using the trypan blue exclusion method. Clinical studies were then performed on 25 periodontally healthy volunteers. The inhibitory effect of chewing mastic gum against mutans streptococci in saliva was compared to a placebo gum. Saliva samples were taken from the subjects immediately before and after chewing the mastic gum and the placebo gum for 15 min. Additional saliva samples were collected every 30 min. The samples were inoculated onto mitis salivarius-bacitracin agar and incubated for 48 h anaerobically at 37 degrees C. The total number of viable bacteria was then counted. RESULTS: Among tested solvents (chloroform, acetone, petrolium ether and ethanol), it was found that the acetone was found to be more convenient than the others to dissolve the mastic gum. In the cytotoxicity assay, concentrations up to 75 mg/ml of the mastic gum were not toxic for the replication of HEp-2 cells. Thus, lower concentrations of mastic gum (20 and 50 mg/ml) were used for the experiments. In vitro experiments, the diameters of growth inhibition zones of mastic gum were in the range 9.0-27.0 mm. In the clinical trials, the mean number of bacteria in samples taken after chewing the mastic gum and placebo gum were following; at minute 15 was 112 x 10(4)+/-268 x 10(3) and 175 x 10(4)+/-417 x 10(3)cfu/ml, for minute 45 was 85 x 10(4)+/-219 x 10(3) and 165 x 10(4)+/-329 x 10(3)cfu/ml, at minute 75 was 65 x 10(4)+/-100 x 10(3) and 160 x 10(4)+/-216 x 10(3)cfu/ml, at minute 105 was 60 x 10(4)+/-127 x 10(3) and 150 x 10(4)+/-138 x 10(3)cfu/ml, and at minute 135 was 55 x 10(4)+/-65 x 10(3) and 145 x 10(4)+/-354 x 10(3)cfu/ml, respectively. Significantly fewer bacteria was found in saliva samples collected after chewing mastic gum compared to those after chewing paraffin (p<0.001). CONCLUSIONS: This preliminary study showed that mastic gum had significant antibacterial activity against S. mutans and mutans streptococci and it may be a useful adjunct in the prevention of caries.

Adult↗
PubMed1984

Allergic contact dermatitis to compound tincture of benzoin.

Nineteen cases of allergic contact dermatitis to compound tincture of benzoin are described. Patch testing to individual components revealed positive reactions to all ingredients except aloe. An alternative preparation, Mastisol, was successfully used without primarily inducing allergy. It should be considered for use before benzoin because once allergy to benzoin exists, cross-reactions to Mastisol usually occur. This is probably due to the presence of a common ingredient, styrax gum.

Adolescent↗