Lipoidal Components Research Articles

Formation of a Stable Co-Amorphous System for a Brick Dust Molecule by Utilizing Sodium Taurocholate with High Glass Transition Temperature.

Brick dust molecules are usually poorly soluble in water and lipoidal components, making it difficult to formulate them in dosage forms that provide efficient pharmacological effects. A co-amorphous system is an effective strategy to resolve these issues. However, their glass transition temperatures (Tg) are relatively lower than those of polymeric amorphous solid dispersions, suggesting the instability of the co-amorphous system. This study aimed to formulate a stable co-amorphous system for brick dust molecules by utilizing sodium taurocholate (NaTC) with a higher Tg. A novel neuropeptide Y5 receptor antagonist (AntiY5R) and NaTC with Tg of 155 °C were used as the brick dust model and coformer, respectively. Ball milling formed a co-amorphous system for AntiY5R and NaTC (AntiY5R-NaTC) at various molar ratios. Deviation from the theoretical Tg value and peak shifts in Fourier-transform infrared spectroscopy indicated intermolecular interactions between AntiY5R and NaTC. AntiY5R-NaTC at equal molar ratios resulting in an 8.5-fold increase in AntiY5R solubility over its crystalline form. The co-amorphous system remained amorphous for 1 month at 25 °C and 40 °C. These results suggest that the co-amorphous system formed by utilizing NaTC as a coformer could stably maintain the amorphous state and enhance the solubility of brick dust molecules.

Investigation of lipoidal matter of Chenopodium quinoa seeds and its cytotoxicity potential against three human cancer cell lines

Background and objectives Quinoa (Chenopodium quinoa Willd) is a plant species that belongs to Chenopodiaceae family. It has a high nutritional value as it is rich in proteins, lipids, and fiber, and has an extraordinary balance of essential amino acids, vitamins, and minerals, in addition to a high number of health-beneficial phytochemicals, including saponins and phytosterols. The present study aims to investigate the lipoidal components of C. quinoa and assessment of C. quinoa lipoidal components and different fractions (methanol, chloroform, ethylacetate, and butanol) cytotoxicity potential against three human cancer cell lines using MTT reduction assay. Materials and methods The seeds of C. quinoa were extracted by different solvents and the extracts prepared were tested for their lipiodial constituents and cytotoxic activities in three cancer cell lines. Results and conclusion The results obtained from Gas Liquid Chromatography (GLC) analysis of nonsaponifiable fraction of C. quinoa seeds indicated that it consists mainly of a mixture of a series of n-alkanes and sterols (79.96 and 7.91%. respectively). The oil was also found to be rich in linoleic acid (52.7%) and oleic acid (25.33%). The investigation of the cytotoxic potential of the plant’s low polarity fractions, including CHCl3, and nonsaponifiable fraction against the studied cell lines revealed the sensitivity of A549 human lung cancer cells. Further studies are needed to uncover the mechanism and chemical constituents of the obtained activity of C. quinoa.

An in vitro drug release rate method for lipoidal materials

A multiparticulate preparation of an osmotically mediated, controlled release system for lipoidal materials is described. Spherical beads containing a lipid carrier, an osmotic agent and a lipid soluble model drug were made and a microporous, polymeric coating applied. When placed in an aqueous medium, the coated beads controllably released first the lipid carrier (containing the model drug), then the osmotic agent. A technique is described for measuring the in vitro release rate profile of the lipoidal components of the beads using microporous polypropylene films. Sorption of the lipoidal components by the film occurred following release from the beads in an aqueous medium. Films were removed at specific times for analysis. The lipoidal components were extracted from the film with ethanol and the model drug content determined by spectrophotometry. This technique may be useful for other systems requiring release rate/dissolution testing of lipoidal agents in an aqueous medium.

Epitope expression of gonococcal lipooligosaccharide (LOS). Importance of the lipoidal moiety for expression of an epitope that exists in the oligosaccharide moiety of LOS

Antigenic expression of lipooligosaccharide (LOS) of strain F62 of Neisseria gonorrhoeae, was investigated with mouse monoclonal IgM antibody 3F11. F62 LOS was modified in various ways in order to understand structural requirements for expression of the 3F11-defined epitope. When the LOS was partially deacylated by treating it with 50 m M NaOH at 80°C for 20 min or with anhydrous hydrazine at 80°C for 20 min, the binding of 3F11 to those deacylated LOS samples decreased significantly. Removal of phosphate groups by treatment of the LOS with HF (4 days at 4°C) did not affect the antigenicity at all. Neither did reduction of carboxyl groups in the LOS molecule (by activation of carboxyl groups with a carbodiimide followed by treatment with NaBH 4) alter epitope expression. On oxidation with NaIO 4, the LOS lost its antigenicity completely. The presence of Mg 2+ did not change the circular dichroism (CD) behavior of F62 LOS. However, the partially deacylated LOS samples showed significantly different CD patterns in the 190–200 nm region compared with F62 LOS, which suggests conformational changes of F62 LOS due to the loss of fatty acids in the lipoidal moiety. Oligosaccharide (OS) and lipoidal components obtained after hydrolysis of F62 LOS with 1% acetic acid, were not recognized by the antibody. The antigenicity of OS was not retained by non-stereospecific acylation of OS with decanoyl chloride. We conclude the following: (1) 3F11-defined epitope exists in the OS moiety of F62 LOS; however, for it to be expressed, the carbohydrate moiety must be in a certain conformation that is defined by an overall structure of the LOS molecule. This structure is significantly influenced by some of the fatty acids in the lipoidal moiety of the LOS molecule; (2) the presence of phosphate or 3-deoxy-manno-2-octulosonic acid (dOclA) is not essential for expression of the 3F11-defined epitope; (3) the presence of divalent cations does not affect epitope expression.

Mechanism of enhancement of percutaneous absorption of molsidomine by oleic acid.

The mechanism of percutaneous absorption of molsidomine, enhanced by a two-component system consisting of oleic acid and propylene glycol, was studied in vitro and in vitro in rats. About 10-20% of the oleic acid was absorbed from the skin independently of the oleic acid-propylene glycol ratio. In contrast, about 95% of molsidomine and propylene glycol were transdermally absorbed from the two-component system containing 10% oleic acid in 6 h. The permeability (percent of dose) of molsidomine through the excised rat skin was comparable to that of propylene glycol (both about 80% in 24h). These results suggest that the molsidomine and propylene glycol permeated simultaneously through rat skin. Our proposed mechanism of percutaneous absorption of molsidomine assumes that oleic acid and propylene glycol penetrate into the stratum corneum and improve the permeability of the skin by dissolving hard lipoidal components, and then molsidomine, dissolved in the propylene glycol, passes through the modified stratum corneum.

Isolation and restriction endonuclease analysis of mycobacterial DNA.

A method for the isolation of DNA from mycobacteria propagated in vitro is described that utilizes organic solvents to extract lipoidal components from the outer membrane, and digestion with a protease (nagarse) and lysozyme to penetrate the cell wall. The mycobacterial cells were lysed by the addition of detergent and the DNA was purified by digestion with pronase, sequential phenol and chloroform extractions, and digestion with RNAase A. The isolated DNA, which was obtained in good yields, was of a relatively high Mr and could be readily digested by restriction endonucleases. By this method, the genomes of Mycobacterium avium, M. intracellulare, M. lepraemurium, 'M. lufu', M. marinum, M. phlei, M. scrofulaceum, M. smegmatis and M. tuberculosis were isolated and the restriction endonuclease digestion patterns analysed. Each species could be distinguished by the digestion patterns, indicating that this approach can be used for identifying mycobacterial species. This approach is also sufficiently sensitive to differentiate strains since we were able to distinguish two independently isolated strains of M. tuberculosis, H37 and H4. In addition, no evidence was obtained for the presence of methylcytosine residues in the sequences 5'.CCGG.3',5'.CCCGGG.3',5'.CC(A/T) GG.3' or for methyladenine at 5'.GATC.3' in the DNA of the nine mycobacterial species examined using pairs of restriction enzymes that recognize and cleave at the same nucleotide sequence but differ in their sensitivity to 5-methylcytosine or 6N-methyladenine.

Interference by Herbicidal Inhibitors of Electron Transport with Phosphorylation and Permeability Properties of Chloroplast Membranes

Many herbicides inhibit chloroplast electron transport by interfering with a proteinaceous component of the Qв complex located in the appressed granal membrane. Certain of these herbicides, designated inhibitory uncouplers, also interfere with photophosphorylation and affect other chloroplast-mediated responses, some of which involve components located in the nonappressed granal membrane. The inhibitory uncouplers can be divided into dinoseb (phenolic) types which contain dissociable protons and dicryl (acylanilide) types which are nonionic. The dinoseb types can function as protonophores and shuttle protons across the thylakoid membrane at low concentrations and can alter the integrity of semipermeable membranes at higher concentrations. However, the dicryl types only alter the integrity of the membranes. The inhibitory uncouplers, but not the DCMU-types of electron transport inhibitors: stimulated electron trans- port from DPIPH2 to methyl viologen; inhibited valifiomycin-induced swelling of intact chloroplasts; increased the permeability of the chloroplast envelope to K+ in the absence of an ionophore; prevented energization of the thylakoid membrane by PS I; and increased the permeability of phosphatidyl choline liposomes to protons. Chlorination response patterns obtained with isomers of N-phenyl-2-methylpentanamides in the above reactions, in general, were similar for interference with the Qв complex, i.e., in all assays, dichlorination in the 3,4 or 3,5 positions was associated with maximum inhibitory potency, whereas substitution in an ortho position decreased inhibitory activity. With a series of 1-alkyl-3-(α,α,α-trifluoro-m-tolyl)ureas, maximum inhibition of electron transport was obtained with the butyl derivative, whereas maximum responses for uncoupling and membrane disturbances were obtained with the hexyl or octyl derivatives. Some of the interferences produced by inhibitory uncouplers may result from interactions with the lipoidal components of chloroplast membranes.

Major hydrocarbons of the post‐pharyngeal glands of mated queens of the red imported fire antSolenopsis invicta

AbstractThin layer and column chromatographic analyses showed that hydrocarbons were the major lipoidal components of post‐pharyngeal glands of mated queens of the red imported fire ant,Solenopsis invicta. Gas liquid chromatographic analyses on an OV‐17 column showed four major hydrocarbons which have been identified and confirmed by synthesis and comparative mass spectral analyses as 13‐methylheptacosane, 13,15‐dimethylheptacosane, 3‐methylheptacosane, and 3,9‐dimethylheptacosane. When microgram quantitites of the natural alkanes on filter paper were placed in colonies of ants, the ants clustered on the paper about the sample and proceeded to masticate the paper in the area containing the alkanes.

Studies on the Cuticle of Tomato Fruit

The cuticle of immature and mature tomato fruit is covered by a very thin layer of epicuticular wax. The total cuticular domain, which is 4-10 μm thick, is composed of 2 main regions: (1) A cutinized layer just above the secondary wall of the epidermal cell consists of several strata of deeply staining, globular materials surrounded by non-staining interstices in which dark, tangential, very thin striae are deployed; and (2) a cuticle outside this layer. The cuticle is at first electron lucent mostly but does also have elongated groups of parallel dark striae, 7 nm thick, which are principally tangential. During ripening the cuticle and the cutinized layer achieve similarity in structure, both having irregularly-sized, electron-opaque tangential lamellae, with occasional radial striae. Within the epidermal cell, cutin cystoliths grow down into the secondary wall in the form of vertical hanging prongs or pegs. When they span the cell lumen completely, from outer wall to inner wall, the cystoliths become essentially trabeculae. KMnO 4 , with or without prior fixation with Gilson stain, is taken up strongly by certain lipoidal components of the cuticle.

Antibodies To Mycoplasma pneumoniae: Correlation of Complement Fixation and Tetrazolium Reduction Inhibition Tests

SummaryThe role of lipoidal components of M. pneumoniae as antigenic determinants in vitro and in vivo is described.Sera with TRI or CF titers with lipid antigen of 8 or greater are usually positive in the ID test, suggesting that this test might be used as a screening test for antibody to M. pneumoniae.Since there is a high degree of correlation between TRI and CF titers when lipid extracts of M. pneumoniae are used as antigens, we feel that the lipid CF test will serve as an indicator of neutralizing antibody to M. pneumoniae.

Lipoidal components of bacterial lipopolysaccharides: nature and distribution of fatty acids in Aerobacter aerogenes.

The fatty acid distribution of Aerobacter aerogenes was studied by comparing the fatty acid composition of the lipoidal component of the endotoxin (lipid A) with the fatty acids of the readily extractable native lipids and total cellular fatty acids. The results for total cellular fatty acids and readily extractable native lipids were generally similar, but both quantitative and qualitative differences exist. In addition, profound differences between these two fractions and lipid A were observed. These differences included fewer fatty acids and lower concentrations of unsaturated and cyclopropane fatty acids in the lipid A. Hydroxy fatty acids persisted in the lipid A. The significance of these differences with respect to mammalian toxicity of endotoxins is discussed.

The Combination of Dyes with Growing, Resting, and Killed Bacterial Cells

Many aniline dyes are employed by the microscopist in staining cells for the single purpose of increasing the visiblity of cells and their various constituents. Other dyes are employed as a means of gaining information relative to the physico-chemical structure of the cell or even its physiologic activities. In this latter group are the so-called vital stains, which are presumed to enter and react with certain constituents of the cell while the cell is still living and carrying on at least some of its normal life activities. Some examples of this type of staining are the use of Janus green to demonstrate oxidase granules in leucocytes; the use of neutral red, brilliant cresyl blue, and others, in studying diffusion phenomena in algal and other plant cells; and the use of many of these vital dyes in animal physiology to study the passage of molecules through cell membranes and their accumulation in various tissue cells (Hober, 1945). The chemical structure of the dyes used in vital staining is not markedly different from that of other types of dyes and stains. They may be basic dyes in which, upon ionization, the colored bearing portion of the dye is located in the cation, or they may Fe acid dyes in which the chromophore is located in the anionic fraction. The more widely employed dyes used in vital staining are relatively weak in their basic or acidic properties. That is, they do not tend to ionize to a marked degree. This low degree of ionization may be an important feature of their molecular makeup since Osterhaut (1925) has shown that many weak acids and bases penetrate cellular membranes only as the undissociated molecules. Experiments by Irwin (1927) on the alga Nitella with brilliant cresyl blues at various pH levels, have likewise indicated that the rate at which the dye enters and leaves the cell Ts proportional to the percentage of the dye in an undissociated state. Accumulation of vital dyes within the cytoplasmic or vacuolar materials in plant and animal cells in greater concentrations than exists in the surrounding medium has been explained in several different ways. Such an accumulation is apparently due either to a higher solubility of the dye in the lipoidal components of the cell or to a greater degree of dye adsorption by some protoplasmic fraction such, for example, as nucleoproteins. In

THE RÔLE OF THE "WAX" OF THE TUBERCLE BACILLUS IN ESTABLISHING DELAYED HYPERSENSITIVITY

The purified wax fraction of the tubercle bacillus, which has been previously demonstrated as an essential element in causing delayed tuberculin hypersensitivity in response to the protein of the tubercle bacillus, is now found to have the same activity with regard to a simple chemical antigen, picryl chloride. One injection of this compound with wax intraperitoneally into guinea pigs results in a marked delayed cutaneous hypersensitivity, demonstrable by contact and intracutaneous test, and of long duration. The effect is not related to an adjuvant activity of the wax as defined by ordinary standards. The relationship of these observations to the occurrence of "heteroallergic" phenomena in tuberculosis is discussed. The possibility that the occurrence of spontaneous contact hypersensitivities may depend upon the presence of similarly active lipoidal components of the skin is commented upon.