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PubMed2004

Epicuticular wax of large and small white butterflies, Pieris brassicae and P. rapae crucivora: qualitative and quantitative comparison between diapause and non-diapause pupae.

We compared the quantity and quality of the epicuticular wax of diapause and non-diapause pupae in two closely related Pieris species, P. brassicae and P. rapae crucivora. Main components of their epicuticular wax were identified as hydrocarbons. In P. brassicae, more than 95% of hydrocarbons were saturated regardless of whether the pupae were in diapause or not. In P. rapae crucivora, 93% of hydrocarbons were saturated in non-diapause pupae whereas in diapause pupae 41% were saturated and 59% unsaturated. From measurements of body surface area by nuclear magnetic resonance microimaging, we calculated the average thickness of the wax layer. The thickness in diapause and non-diapause pupae of P. brassicae was 800 and 160 nm, respectively. In P. rapae crucivora, the thickness was 195 nm in diapause and 11 nm in non-diapause. This is the first report to clarify the compositional difference in epicuticular wax between diapause and non-diapause pupae.

Animals↗

PubMed2006

Leaf epicuticular wax chemicals of the Japanese knotweed Fallopia japonica as oviposition stimulants for Ostrinia latipennis.

Extraction, fractionation, and gas chromatography-mass spectrometry analyses guided by bioassays have shown that n-alkanes and free fatty acids in leaf epicuticular wax of the Japanese knotweed Fallopia (Reynoutria) japonica stimulate oviposition in the Far-Eastern knotweed borer, Ostrinia latipennis (Lepidoptera: Crambidae). n-Alkanes made up 48.1% of the total amount of epicuticular wax, and their carbon chain length was in the C(16)-C(33) range, with n-nonacosane (n-C(29)) most abundant, followed by n-C(27), n-C(25), and n-C(31). Free fatty acids with C(9)-C(22) accounted for 22.3%, and hexadecanoic acid was predominant. A mixture of authentic n-alkanes and fatty acids of the composition found in the epicuticular wax, a mixture of n-alkanes, and a mixture of fatty acids significantly enhanced oviposition. Thus, it was demonstrated that both n-alkanes and free fatty acids in leaf epicuticular wax of F. japonica are naturally occurring oviposition stimulants for O. latipennis.

Alkanes↗

PubMed1992

Mandibular complete denture impressions with fluid wax or polysulfide rubber: a comparative study.

Some authors have stated that wax cannot be used to make impressions for complete dentures, while others have found that wax has some advantages over elastomeric impression materials. The purpose of this study was to compare mandibular impressions made with a fluid wax to those made with light-body polysulfide rubber. Fifteen maxillary and mandibular complete dentures were made using fluid wax as a final impression material. For comparison, 15 maxillary and mandibular complete dentures were made using light-body polysulfide rubber. The number of adjustments required over 1 year was recorded. No statistical difference in adjustments was noted between the two groups.

Aged↗

PubMed1983

Reproduction and subchronic feeding study of carnauba wax in rats.

The reproductive performance of Wistar rats fed carnauba wax at levels of 0.1, 0.3 or 1% in the diet and the effects of subchronic administration of carnauba wax at these dose levels on the resultant progeny were studied. Reproductive indices, body-weight gain, food consumption, haematological and clinical chemical data, ophthalmic, gross and histopathological examinations were used to study the possible toxic or pathological effects. Serum free fatty acid levels were found to be decreased in male and female rats fed carnauba wax at dietary levels of 0.3 and 1.0%. No other effects of feeding carnauba wax at levels up to 1.0% of the diet were observed.

Animals↗

PubMed1996

Comparison of Super Stuff and paraffin wax bolus in radiation therapy of irregular surfaces.

Irregular facial contours can make radiation therapy of head and neck tumors difficult. Isodose lines become skewed, making treatment planning complex. A traditional solution to this problem is the paraffin wax box bolus. Such a bolus is made to fit the irregular surface compensating for the topology and creating an even surface. The fabrication of a wax bolus can be a difficult and time-consuming process. A method that is simple and efficient has been devised. Super Stuff bolus can be easily molded and has approximately the same effect as a similar paraffin wax bolus. This was verified by irradiating a Rando head phantom with both a paraffin wax bolus and a Super Stuff bolus. Doses to various points of interest were measured with thermoluminescent dosimetry (TLD) chips (LiF). The particular case addressed is malignant melanoma of the nasal septum, but the technique described can be useful in the treatment of other sites as well.

Carboxymethylcellulose Sodium↗

PubMed2006

Cloning and characterization of a lupeol synthase involved in the synthesis of epicuticular wax crystals on stem and hypocotyl surfaces of Ricinus communis.

Pentacyclic triterpenoids are a large group of secondary metabolites found in many different plant species, either as glycoside conjugates or as aglycones. The latter in many cases accumulate to high amounts in the cuticular wax and hence at the surface of plant organs. In the present work, the cuticle-specific formation of triterpenoids was investigated in Ricinus communis stems, combining analytical and molecular genetic methods. Two phenotypes of castor bean could be distinguished based on the glaucous or glossy appearance of the surfaces of all stem portions including the hypocotyls, and were due to the presence or absence of thread-shaped epicuticular wax crystals, respectively. Comparative studies showed that these crystals are formed by the triperpenoid lupeol, present in high amounts on all stem surfaces. On the hypocotyl portion of stems, lupeol was found to accumulate rapidly during early development of the surface (10-15 days after emergence). Mature hypocotyls of glossy individuals were covered with 12.5 microg/cm2 of wax containing approximately 1% of lupeol, whereas the glaucous phenotype had a wax load of 51.9 microg/cm2 with 56% of lupeol. Two oxidosqualene cyclases from castor bean were cloned, functionally expressed in yeast, and characterized as a cycloartenol synthase (RcCAS) and a lupeol synthase (RcLUS). Phylogenetic analyses revealed that RcLUS is similar to two clades of known lupeol synthases, but also exhibits some similarities with beta-amyrin synthases. Both the organ-specific expression of RcLUS and the expression pattern during hypocotyl development exactly matched the accumulation of cuticular lupeol in castor bean. In contrast, RcCAS was constitutively expressed in all organs at various times. We conclude that the RcLUS enzyme is responsible for formation of the cuticular lupeol, and thus for the characteristic surface properties of R. communis stems.

Amino Acid Sequence↗

PubMed2005

Novel method for titanium crown casting using a combination of wax patterns fabricated by a CAD/CAM system and a non-expanded investment.

OBJECTIVES: For titanium casting, most commercial investments for titanium recommend casting at a low mold temperature to reduce oxidation. However, the thermal expansion values of the molds at low casting temperatures may be insufficient. The purpose of the current study was to investigate the possibility of obtaining accurate titanium crown casts using wax pattern fabricated by a CAD/CAM system with a non-expanded mold. METHODS: Three types of experimental magnesia-based investments (A, B and C) were made and their properties were evaluated for dental use. Two kinds of wax patterns for full-coverage coping crowns (S-0: cement space of 0 microm; S-20: cement space of 20 microm) were fabricated using a commercial CAD/CAM system. A traditional method (TM) using inlay wax was performed for comparison. The investment for titanium casting was decided from the fundamental data of experimental investments. Titanium crowns were replaced on the stone die and the thickness of the cement layer was evaluated. RESULTS: There were no significant differences for the setting time and setting expansion among the experimental investments, but the aluminous cement content played a role in hardening and contracting the mold. The fit of the titanium crowns differed significantly between the TM and the CAD/CAM system. The ranges of thickness obtained from the TM, S-0 and S-20 were 20.78-357.88 microm, 25.12-107.46 microm and 17.84-58.92 microm, respectively. SIGNIFICANCE: High quality titanium crown casting was obtained using a combination of wax patterns fabricated by a CAD/CAM system and a non-expanded MgO-based investment.

Analysis of Variance↗

PubMed2004

Mutagenic activity of sweepings and pigments from a household-wax factory assayed with Salmonella typhimurium.

The mutagenic activity of garbage originating from a household wax industry was determined by the Salmonella/microsome assay, using the bacterial strains TA100, TA98 and YG1024. The garbage was obtained by sweeping the floor of the factory at the end of the work shift. Organic compounds were extracted by ultrasound for 30 min in dichloromethane or 70% ethanol. After evaporation of solvent, these extracts (HFS: household-wax factory sweepings) were dissolved in DMSO, and were tested for the mutagenic activity at varying concentrations (HFS-ET: 0.08-0.68 mg/plate, HFS-DCM: 0.60-7.31 mg/plate). The colouring agents (pigments) used in the production of the wax were also dissolved in DMSO and tested with the assay. The concentrations tested for each pigment were: Amaranth: 0.46-3.65 mg/plate, Auramine: 0.15-1.2 mg/plate and Rhodamine B: 0.22-1.82 mg/plate. Both ET and DCM organic extracts had mutagenic activity, especially in the YG1024 strain. The pigments behaved in a similar way, demonstrating that YG1024 was the most sensitive strain for the detection of mutagenicity, and that metabolization increased the activity. Human exposure (occupational and non-occupational) to industrial residues generated during the household-wax manufacturing and packaging process should be monitored, since this type of garbage is normally deposited in the environment without any control.

Animals↗

PubMed2005

Endoscopic management of cerebrospinal fluid leak associated with the use of bone wax in skull-base surgery.

OBJECTIVE: To alert otolaryngologists to consider the possibility that bone wax may be associated with cerebrospinal fluid leaks that occur immediately after skull-base craniotomy approaches. STUDY DESIGN AND SETTING: Clinical report from surgical experience in a tertiary care setting. RESULTS: Three patients presented with brisk cerebrospinal fluid leak after craniotomy. Sinus endoscopy revealed bone wax within a small parasphenoid defect in all 3 cases. CONCLUSIONS: Bleeding from areas of the skull base adjacent to the paranasal sinuses during craniotomy can signal a small breach of the skull base. Bone wax may control bleeding from edges of transected bone but also stent the skull-base defect open, preventing fibrin deposition and spontaneous healing and closure. SIGNIFICANCE: Otolaryngologists repairing a cerebrospinal fluid leak after a skull-base craniotomy approach should consider the possibility of encountering bone wax and be able to identify it to better treat their patient.

Adult↗

PubMed2005

Spores of Ascosphaera apis contained in wax foundation can infect honeybee brood.

Chalkbrood disease in honeybees (Apis mellifera L.) is caused by an infection with Ascosphaera apis. Disease expression requires the consumption of fungal spores and a predisposing condition in the susceptible brood. A. apis spores within sheets of wax foundation could be a source of inoculum leading to chalkbrood, but it is also possible that these spores remain confined in the wax and do not contribute to disease. We have resolved this topic by chilling susceptible brood within wax combs built on contaminated foundation (using treatments of spores from 1 mummy and spores from 10 mummies) versus uncontaminated foundation. We found significantly higher levels of chalkbrood in brood exposed to the higher dosage. Our results demonstrate that foundation wax contaminated with spores of A. apis spores may be a source of chalkbrood in honeybee colonies.

Animals↗

PubMed1997

The effect of storage time of removable partial denture wax pattern on the accuracy of fit of the cast framework.

STATEMENT OF PROBLEM: Situations may arise in dental laboratories that could result in a time lapse between preparing the wax pattern of the removable partial denture framework and its casting into the cobalt-chromium alloy. PURPOSE: This study investigated the effect of storage time of the wax pattern before casting and the influence of the palatal major connector design on the accuracy of its fit on the master casts. MATERIAL AND METHODS: Forty-two frameworks were prepared with two designs of major connectors, which were divided into three subgroups according to the storage time of the wax patterns: 24 hours, 1 week, and 1 month. Discrepancies in the fit of the connectors to their respective casts were measured at specific locations for both connector designs. RESULTS: In both framework design groups, there was a significant deterioration in fit (p < 0.0005) of the major connectors with the increase in storage time of their wax patterns on their respective refractory casts. Gap discrepancies were more pronounced towards the center of the palate. CONCLUSIONS: The greatest discrepancies appeared at the middle sections of the connectors more than at the lateral section (p < 0.0005). Furthermore, frameworks with modified palatal plate major connectors exhibited greater inaccuracies in their fit than those with the anterior posterior palatal strap design, as evidenced by the increase in mean gap discrepancies under the palatal plate design (p < 0.0005).

Analysis of Variance↗

PubMed2002

Composition of sugarcane waxes in rum factory wastes.

Wastes produced during fermentation and distillation of crude sugarcane juice in rum factories were evaluated as a new source of waxes. The chemical composition of the crude wax extracted from adsorbat of the wastes on fuller's earth was studied by GC-mass spectrometry. Series of linear alkanes (C19-C33), and wax esters constitute the main components. In addition, phytosterols, triterpene methyl ethers, ethyl and methyl esters of fatty acids, and free fatty acids were found as minor components. Acid (predominance of C16 and C18) and alcohol portions (C26-C32) of the wax esters were analysed after saponification.

Alcoholic Beverages↗

PubMed1997

Epicuticular wax variation in ecotypes of Arabidopsis thaliana.

Quantification of the epicuticular wax from the stems of 40 ecotypes of Arabidopsis thaliana showed a two-fold range in total wax load that was not correlated to known abiotic characteristics of the ecotype's origin of collection. Chemical analysis of these ecotypes revealed similar epicuticular wax profiles for all ecotypes except CT-1. In CT-1 the amount of 22 and 24 carbon length primary alcohols was increased by 16- and 8-fold, respectively, over that observed in the epicuticular wax averaged over all ecotypes.

Animals↗

PubMed2000

Matrix mini-tablets based on starch/microcrystalline wax mixtures.

Matrix mini-tablets based on a combination of microcrystalline waxes and starch derivatives were prepared using ibuprofen as a model drug. The production of mini-tablets was preferred over the production of pellets, as up-scaling of the pelletisation process seemed problematic. Prior to tabletting, melt granulation in a hot stage screw extruder and milling were required. The in vitro drug release was varied using microcrystalline waxes with a different melting range, the slowest drug release being obtained with a formulation containing a microcrystalline wax with a melting range between 68 and 72 degrees C. Generally speaking increasing the wax concentration resulted in a slower drug release. In vitro drug release profiles were also modified using different starches and mixtures of starches. Increasing the ibuprofen concentration to 70% resulted in a faster drug release rate.

Capsules↗

PubMed2002

Wax beads as cushioning agents during the compression of coated diltiazem pellets.

Placebo particles were mixed with film-coated diltiazem pellets to evaluate them as cushioning agents during tabletting in order to protect the film coat from damage. The cushioning properties of alpha-lactose monohydrate granules, microcrystalline cellulose pellets and wax/starch beads were evaluated by comparing the dissolution profile of the coated pellets before and after compression (compression force 10 kN). Only the tablet formulations containing wax/starch beads provided protection to the film coat. However, the dissolution rate of tablets formulated with waxy maltodextrin/paraffinic wax placebo beads was too slow as the tablets did not disintegrate. Adding 50% (w/w) drum-dried corn starch/Explotab/paraffinic wax beads to the formulation was the optimal amount of cushioning beads to provide sufficient protection for the film coat and yield disintegrating tablets. Using a compression simulator, the effect of precompression force and compression time on the dissolution rate was found to be insignificant. The diametral crushing strength of tablets containing 50% (w/w) drum-dried corn starch/Explotab/paraffinic wax beads was about 25.0 N (+/-0.3 N), with a friability of 0.4% (+/-0.04%). This study demonstrates that adding deformable wax pellets minimizes the damage to film-coated pellets during compression.

Compressive Strength↗

PubMed1987

Effects of bone wax on rabbit cranial bone lesions.

The present study was designed to elucidate the reactions of cranial membranous bone to bone wax. In ten young rabbits, twenty parietal bone defects were created by drilling, the edges of which were partly extended using rongeur forceps to enable investigation of eventual thermal effects. Half of the marginal bone surrounding the lesions was covered by bone wax, the remainder serving as control. The animals were sacrificed 1 and 7 weeks after surgery, and block specimens prepared for light microscopy. Merely slight tissue reactions to the bone wax were discerned. Bony regeneration occurred mainly from the dura mater and the pericranium, but also from the bony rim. Reskeletalization was markedly impaired by the presence of bone wax. Heat generated by drilling caused reduced bone formation despite constant irrigation peroperatively. Clinical consequences are discussed.

Animals↗

PubMed2002

Effect of gamma-irradiation combined with washing and waxing treatment on physicochemical properties, vitamin C, and organoleptic quality of Citrus clementina Hort. Ex. Tanaka.

To enhance the shelf life of a late variety of Moroccan Citrus clementina (Nour), ionizing treatments were applied at 0.3 kGy, as well as washing (cold water) and waxing treatments. It has been found that, despite the irradiation treatment, the washing and waxing treatment do not improve the quality of C. clementina, but rather result in yellower peels, peel injury, and reductions of vitamin C content, acidity, and soluble solids. However, gamma-irradiation alone enhanced significantly (p <or= 0.05) the level of vitamin C and the total phenolic content and maintained the color of the C. clementina during the entire storage period (49 days at 3 +/- 1 degrees C and 84% relative humidity). Finally, sensory evaluation further confirmed the beneficial effect of gamma-irradiation. Irradiated clementines were found to be sweeter. Also, the sensorial score of irradiated (I) and washed, waxed, and un-irradiated (LC) fruits was maintained over 7 days during 21 days as compared to 14 days for unwashed, unwaxed, and un-irradiated (C) and for washed, waxed, and irradiated (LCI) fruits.

Ascorbic Acid↗

PubMed1999

Grapefruit gland oil composition is affected by wax application, storage temperature, and storage time.

The effect of wax application, storage temperature (4 or 21 degrees C), and storage time (14 or 28 days after wax application) on grapefruit gland oil composition was examined by capillary gas chromatography. Wax application decreases nonanal and nootkatone levels. beta-Pinene, alpha-phellandrene, 3-carene, ocimene, octanol, trans-linalool oxide, and cis-p-mentha-2,8-dien-1-ol levels increase, but limonene levels decrease, with temperature. Levels of alpha-pinene, limonene, linalool, citronellal, alpha-terpineol, neral, dodecanal, and alpha-humulene decrease with time. Levels of alpha-phellandrene, 3-carene, ocimene, and trans-linalool oxide increase with time. No compound level was affected by the interactive action of temperature and wax application, suggesting that these two factors cause grapefruit oil gland collapse (postharvest pitting) through means other than changing gland oil composition. Compounds that are toxic to the Caribbean fruit fly (alpha-pinene, limonene, alpha-terpineol, and some aldehydes) decrease with time, thus suggesting grapefruit becomes increasingly susceptible to the fly during storage.

Citrus↗