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At least 19 recordsLinked to original sources
PubMed1977

Arthritogenicity of wax D from various mycobacteria related to oil vehicle composition and to the combination with poly I:C, cord factor and acetylated wax D.

Most of wax D (peptidoglycolipid) used here appeared to be ineffective for production of arthritis when given in a water-in-oil emulsion, while the same wax D in squalane was very effective for production of arthritis. Arlacel A as an emulsifier appeared to suppress the arthritogenicity of wax D in squalane, probably through some interaction with the arthritogenic portion of wax D. Poly 1:C seemed to remarkedly enhance the arthritogenicity of wax D, even in water-in-oil emulsion. Acetylated wax D and cord factor (trehalsoe-dimycolate) were much less effective than poly 1:C. Delayed skin hypersensitivity to PPD, peptidoglycan and poly 1:C was also remarkedly affected by oil composition. However, there was no correlation between these delayed hypersensitivities and development of arthritis.

Adjuvants, Immunologic↗
PubMed1977

[Rheological studies on deformation for dental waxes. 2. Stress relaxation behavior of inlay wax (author's transl)].

The rheological properties of inlay wax were investigated by experiment of stress relaxation, thermal expansion, thermal analysis and X-ray diffraction. The results obtained were as follows. The solid-solid phase transition caused by phase transition of paraffin was observed. The stress relaxation curves of inlay wax were obtained at various temperature, and from these curves the stress relaxation master curve was composed by application of time-temperature superposition principle. The temperature dependence of sift factor was devided into two regions of Arrhenius type, and the activation energy was about 60 kcal/mol at the temperature lower than 23 degrees C and 120 kcal/mol at higher temperature. This fact suggests that the relaxation mechanism of inlay wax can be classified into two different modes. The relaxation mechanism at lower temperature region is explained by crystalline relaxation, and at higher temperature is considered to depend upon the solid-solid phase transition process of inlay wax. Calculating from the activation energy, for each 2 degrees C rise in temperature, the rate of rheological change for inlay wax is approximately two-fold at lower temperature region, and about four-fold at higher temperature region.

Elasticity↗
PubMed1978

Sustained release from inert wax matrixes I: drug-wax combinations.

The melting and energy characteristics of several drug-wax combinations were investigated using differential scanning calorimetry. The phase diagrams of binary mixtures of tripelennamine hydrochloride and tolazoline hydrochloride with carnauba wax and castor wax showed no eutectic formation and gave no indication that a significant interaction was involved. However, in tripelennamine mixtures, a slight depression in the drug melting point was observed at around 50% concentration. For ternary systems, i.e., drug, carnauba wax, and stearyl alcohol, thermograms of samples prepared by a fusion method differed slightly from those obtained with mixtures formulated by dissolving all ingredients in chloroform and evaporating the solvent. However, the location of the peak of each component remained essentially the same. A plot of melting point versus concentration of each compound showed insignificant changes in melting point and indicated that no interaction was occurring. The phase diagrams suggested that the combinations are strictly physical and that it is the physical characteristics, such as the hardness and composition of the core and drug particle size, that influence the release or dissolution of drug from the waxy matrix.

Chemistry, Pharmaceutical↗
PubMed1992

Observation on the composition and biosynthesis of egg wax lipids in the cattle tick, Boophilus microplus.

The biosynthesis of wax lipids by Gené's organ, the egg waxing organ in ticks, was investigated. Gené's organ, a complex dermal gland system, applies a superficial wax layer to the eggs during oviposition which prevents desiccation and is essential for egg viability. The detailed anatomy and histology of the three gland cell types are unambiguously described. Serial sectioning of ticks showed that all three gland cell types are capable of contributing to the egg wax. The wax synthetic ability of these three gland types was characterized. The composition of wax lipids extracted from the surface egg wax, and from the three types of wax gland dissected from ovipositing ticks, was analysed using thin-layer and gas-liquid chromatography. Injection of ovipositing ticks with radiolabelled acetate resulted in the incorporation of the label into wax lipids by gland cells of Gené's organ. The egg wax was a complex mixture of long-chain alkanes and fatty acid esters. The gland cells contained a greater proportion of shorter chain alkanes than were present in the egg surface wax. Some unsaturated long-chain fatty acids were present, and these were more abundant in the gland cells than in the surface wax of oviposited eggs, suggesting that oxidation occurs after oviposition. The results confirm that the tubular glands, acinar accessory glands and lobular glands of Gené's organ all contribute to the egg waxes, although the lipid components differed in relative abundance. The results are also consistent with alkane synthesis from fatty acids in Gené's organ by a chain-elongation-decarboxylation pathway.

Alkanes↗
PubMed1977

Occurrence and patterns of waxes in Neisseriaceae.

Forty-five strains classified in the family Neisseriaceae were analysed for wax esters by gas-liquid chromatography. The amounts and types of waxes varied between the taxa. Waxes were not detected in 16 strains of 'true neisseriae' (genus Neisseria) or in two strains of Kingella, but they were found in all 'false neisseriae', in all species of Moraxella except Moraxella phenylpyrouvica, in five out of 10 strains of Acintobacter, and in all strains of a group of psychrophilic, oxidase-positive organisms. The chain lengths of the wax esters ranged from C24 to C42, with C36 predominating. In all taxa, esters with even numbers of carbon atoms constituted 70 to 100% of the total. Saturated, mono-unsaturated and diunsaturated waxes were found. Acinetobacter strains were characterized by large amounts (30 to 98%) of di-unsaturated wax esters; such waxes did not exceed 8% in the 'false neisseriae' or Moraxella spp. Waxes of strains belonging to the psychrophilic, oxidase-positive group generally resembled those found in Moraxella. Wax esters with odd numbers of carbon atoms were abundant in M. lacunata (29%), M. atlantae (15%) and in the psychorophilic group (19 to 28%); long-chain esters (C40 or above) were characteristic of M. atlantae (30%) and one strain of M. osloensis (26%).

Chromatography, Gas↗
PubMedDate not supplied

Process and formulation variables in the preparation of wax microparticles by a melt dispersion technique. I. Oil-in-water technique for water-insoluble drugs.

Ibuprofen-wax (carnauba, paraffin, beeswax, and the semisynthetic glyceryl esters--Gelucire 64/02 and Precirol ATO5) microparticles were prepared without organic solvents as an alternative to polymeric microparticles. In the melt dispersion technique, the drug-wax melt was emulsified into a heated aqueous phase followed by cooling to form the microparticles. The microparticles were characterized with respect to their drug loading, and morphological and release properties. They were spherical and non-agglomerated and drug loading close to 60 per cent were achieved. The more hydrophilic waxes (Gelucire 64/02 or Precirol ATO5) could be prepared without the use of surfactants. With the other waxes, increasing amounts of sodium lauryl sulphate in the external aqueous phase decreased the drug loading because of drug solubilization when compared to the polymeric stabilizer, poly(vinyl alcohol). The type of wax, the rate of cooling, and the temperature of the aqueous phase had no significant effect on the drug loading because of the low solubility of the drug in the external aqueous phase. The drug release was controlled by the hydrophobicity of the wax. Besides ibuprofen, other water-soluble drugs (ketoprofen, indomethacin, hydrocortisone) were also encapsulated by this method. The wax microparticles could be formulated into an aqueous sustained-release oral suspension dosage form.

Delayed-Action Preparations↗
PubMed1975

Waxed windshields are hazardous in the rain.

Seven automobiles were washed and waxed at four car washes. Photographic determinations were made of the glare produced by the wet or dry waxed windshield in a headlight beam. When wet, the waxed windshields scattered three times more light than in the normal human eye. The wet wax scattering was 24.8 times higher than when dry. No wax residues should be permitted on windshields and the National Highway Traffic Safety Administration should issue a mandatory windshield cleaning requirement after waxing.

Automobile Driving↗
PubMed1979

Acyl-CoA reductase specificity and synthesis of wax esters in mouse preputial gland tumors.

Long-chain alcohols are synthesized in the mouse preputial gland tumor (ESR-586) by NADPH:acyl-CoA oxidoreductase. In this study, a series of labeled acids was tested as substrates for the oxidoreductase in a cell-free system from the tumor, and the distribution of label into alcohols, waxes, and other products was determined. The system contained the labeled acid, an acyl-CoA-generating system, an NADPH-generating system, and tumor homogenate. The highest rates of alcohol synthesis were obtained with palmitic (16:0), heptadecanoic (17:0), stearic (18:0), myristic (14:0), elaidic (18:1 trans), and linoleic (18:2) acids, which yielded, respectively, 151, 124, 102, 76, 65, and 35 pmol alcohol/min per mg protein. Decanoic (10:0), lauric (12:0), oleic (18:1 cis), linolenic (18:3), arachidonic (20:4), and behenic (22:0) acids all gave lower activities. Acyl-CoA formation did not appear to be rate limiting with any of the substrates tested except behenic acid. In addition to the fatty alcohol product, a small amount of fatty aldehyde was formed in the system. Incorporation of the labeled fatty acids into wax esters was examined and the distribution of label between the alcohol and acid components of the waxes was determined. Incubation of [1-(14)C]palmitic acid yielded 3.4% free alcohol, 8.3% alcohol esterified in waxes, and 7.7% palmitoyl groups esterified into waxes, whereas, at the other extreme, [1-(14)C]linolenic acid yielded 0.8%, 0.6%, and 38%, respectively, into the homologous components.-Wykle, R. L., B. Malone, and F. Snyder. Acyl-CoA reductase specificity and synthesis of wax esters in mouse preputial gland tumors.

Animals↗
PubMed1977

Comparison of the mode of immunopotentiating action of BCG and wax D. II. Effect on the methylcholanthrene carcinogenesis.

The effects of BCG and wax D on methylcholanthrene (MCA) carcinogenesis in mice were studied. BCG given 8 weeks after MCA administration conferred a significant protection against carcinogenesis. When given either on the same day as MCA injection or 4 weeks after MCA, BCG slightly increased tumor incidence. Wax D provided a marked protection against tumor development when given 4 weeks after MCA. An enhanced tumor development was obtained, when wax D was administered either on the day of MCA injection or 8 weeks after MCA. These results indicated that the effects of BCG and wax D on MCA carcinogenesis varied with the timing of administration. When BCG and wax D increased the level of delayed type hypersensitivity (DTH) at the initiating time of tumor development, a protection against carcinogenesis was obtained. On the other hand, BCG and wax D enhanced tumor development, when it increased antibody formation at the time of initiation of tumor development.

Animals↗
PubMed1992

Effect of active hand exercise and wax bath treatment in rheumatoid arthritis patients.

The effect of active hand exercise and warm wax treatment was evaluated in 52 rheumatoid arthritis patients randomized into four groups: (1) both exercise and wax bath, (2) exercise only, (3) wax bath only, and (4) controls. Treatment was given three times a week for 4 weeks. Deficits in flexion and extension in digits II-V bilaterally, grip function, grip strength, pain, and stiffness were measured before and after the treatment period. The control group was measured at corresponding times. Wax bath treatment followed by active hand exercise resulted in significant improvements of range of motion (ROM) and grip function. Active hand exercise alone reduced stiffness and pain with nonresisted motion and increased ROM. Wax bath alone had no significant effect.

Adult↗