Experimental studies on the role of alkyl lysophospholipids in autologous bone marrow transplatation

The selective cytocidal effect of alkyl lysophospholipids against neoplastic cells while sparing normal cells make these ideal candidates for purging leukemic cells from bone marrows obtained during remission. To test the feasibility of such an approach, a murine model and an in vitro human cell model were developed. In the murine system a mixture of normal bone marrow cells and WEHI IIIB myelomonocytic leukemic cells was incubated with varying doses of 1-O-octadecyl-2-O-methyl-rac-glycero-3-phosphocholine (ET-Me) for 24 hr before being injected into tail veins of lethally irradiated Balb/c mice. At doses of 20 and 100 μg/ml, long-term survivors were noted. The additional steps of freezing and thawing following incubation resulted in significantly longer survival with doses of 10 to 50 μg/ml, but were toxic to marrow stem cells at 100 μg/ml. In the in vitro model, normal marrow progenitor cells and leukemic cells (the promyelocytic cell line HL60) were exposed to varying concentrations of ET-Me for 1 and 4 hr alone or mixed, and clonogenicity was assayed by colony formation in semisolid medium during 7–14 days’ incubation. At doses up to 100 μg/ml exposed for 4 hr normal progenitor cells were spared and HL60 colonies eliminated. Other phospholipids analogues were less effective in eliminating leukemic cells, but spared normal progenitor cells. A survey of fresh leukemic cells found varying degrees of sensitivity to ET-Me, indicating the need for testing a variety of compounds. These studies clearly indicated the potential usefulness of alkyl lysophospholipid compounds in selectively purging leukemic cells from remission marrows for autologous bone marrow transplantation.     

Immunomodulatory and therapeutic properties of alkyl lysophospholipids in mice

This paper describes the immunomodulatory and therapeutic properties of the alkyl lysophospholipids [ALP; 1-O-octadecyl-2-O-rac-glycero-3-phosphocholine (ET-18-OCH₃)]. ALP was able to activate macrophages both in vitro and in vivo as well as to act as an immunoadjuvant for syngeneic tumor vaccines. However, ALP appeared to be transferred, at least in part, to the macrophage membrane, and some of the tumoricidal macrophage-activating properties seem to be associated with the direct cytotoxic effect of membrane-released ALP. ALP also had some therapeutic activity for experimental and spontaneous metastases, requiring administration three but not two times weekly at near-toxic doses; this suggests that at least some of its therapeutic activity is due to direct cytotoxicity.     

Modulation of chemical carcinogenesis in rats by alkyl lysophospholipids

The influence of 1-O-octadecyl-2-O-methyl-rac-glycero-3-phosphocholine (ET-18-OCH₃) and 1-hexadecylmercapto-2-methoxymethyl-rac-propyl-3-phosphocholine (TLP, BM41.440) on methylnitrosourea (MNU)-induced rat mammary carcinomas and of ET-18-OCH₃ on 7,12-dimethylbenzanthracene (DMBA)-induced leukemias was investigated. Both agents effectively delayed MNU-induced mammary tumor formation at high, cytotoxic dosages but TLP had no influence at low “immunomodulatory” doses. ET-18-OCH₃ also significantly protected against leukemia development in DMBA-treated Long-Evans rats.     

Anionic polymerization of alkyl cyanoacrylates: In vitro model studies for in vivo applications

Alkyl cyanoacrylates were polymerized anionically in water medium at different levels of pH. The effect of pH on the molecular weight and softening points of the polymers was studied. Alkyl cyanoacrylates were also polymerized in suspension by using the combination of methanol–water, and also by using different catalysts such as triethylamine, diazabicyclooctane, and diazabicycloundecane. The poly(cyanoacrylates) thus obtained were characterised by infrared and nuclear magnetic resonance spectroscopy. The molecular weight, molecular weight distribution, and the softening points of the polymers were determined. These studies would help in more effective usage of cyanoacrylates as bioadhesives under varied physiological conditions. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 336–344, 1999     

Cytotoxic effects of ether lipids and derivatives in human nonneoplastic bone marrow cells and leukemic cells in vitro

The effects of 2-lysophosphatidylcholine (2-LPC), the alkyl lysophospholipid derivatives (ALP) 1-O-octadecyl-2-O-methyl-rac-glycero-3-phosphocholine (ET-18-OCH₃) and 1-O-hexadecyl-sn-glycero-3-phospho-trimethyl-ammonio-hexanol, the 2-acetamide analog of platelet-activating factor (PAF) 1-O-octadecyl-2-acetamide-sn-glycero-3-phosphocholine, the thioether lysophospholipid derivative (TLP) BM 41.440 and the ether-linked lipoidal amine CP-46,665 on tritiated thymidine uptake and trypan blue dye exclusion were tested in vitro in various freshly explanted cell samples from human nonneoplastic bone marrow and human leukemias. In both assay systems, a dose range of 1–20 μg/ml of the compounds was tested after 24, 48 and 72 hr of coincubation with the cells. The trypan blue dye exclusion revealed statistically significant preferential cytotoxicity in leukemic cells for three compounds with the order of quantitative selectiveness: ET-18-OCH₃>BM41.440>2-acetamide analog of PAF. CP-46,665 was the most toxic compound, but did not reveal significant differences between nonneoplastic bone marrow and leukemic cells when added in concentrations greater than 1 μg/ml. The trimethyl-ammoniohexanol compound showed only minor activity in the majority of tests, when added at concentrations <20 μg/ml. 2-LPC was rather ineffective. The tritiated thymidine uptake showed only preferential antiproliferative effects towards leukemic cells of ET-18-OCH₃ and, sometimes, within the dose time frame tested of BM 41.440. All compounds tested except 2-LPC and the trimethyl-ammonio-hexanol compound were active also in this assay (inhibition of uptake>50% of the controls). Based on these results, ET-18-OCH₃ and BM 41.440 are recommended for experimental bone marrow purging.     

Preparations and reactions of alkyl ethers of some aldohexoses

Aldohexose, such asd-glucose,d-galactose ord-mannose, reacted with acetone to give the following O-isopropylidene derivatives: 1,2;5,6-di-O-isopropylidene-d-glucofuranose (IA), 1,2;3,4-di-O-isopropylidene-d-galactopyranose (IB) or 2,3;5,6-di-O-isopropylidene-D-mannofuranose (IC). The O-isopropylidene derivative (IA～IC) reacted with alkyl/alkenyl halogenide to yield aldohexose ether compounds containing di-O-isopropylidene group, 3-O-alkyl-1,2;5,6-di-O-isopropylidene-d-glucofuranose (II), 6-O-alkyl-1,2;3,4-di-O-isopropylidene-d-galactopyranose (III) or 1-O-alkyl-2,3;5,6-di-O-isopropylidene-d-mannofuranoside (IV), in good yields. The Williamson ether synthesis was carried out using phase-transfer catalysis (PTC). The derived aldohexose alkyl ether containing di-O-isopropylidene group was hydrolyzed to give 3-O-alkyl-1,2-O-isopropylidene-d-glucofuranose (V) as a partial hydrolysis product; the complete hydrolysis of I～IV gave, as expected, 3-O-alkyl-glucopyranose (VI), 6-O-alkyl-galactopyranose (VII) or 1-O-alkyl-mannofuranoside (VIII). Further alkylation of (V) with Mel under PTC and subsequent acid hydrolysis gave 3-O-alkyl-5,6-di-O-methyl-d-glucofuranose (X). Methanolysis of III with catalytic amounts of H₂SO₄ gave 1-O-methyl-6-O-alkyl-d-galactofuranoside (XI). The elucidation of the galactofuranoside skeleton of (XI) was determined by means of its¹³C nuclear magnetic resonance spectra. The O-alkyl aldohexoses, e.g., X and XI, were evaluated and found to be emulsifiers.     

Physical and functional properties of some higher alkyl polyglucosides

The higher alkyl polyglucosides are a new class of nonionic surfactants which can be formulated to give properties ranging from soft greases to hard glassy water-soluble solids melting from about 30 C to above 300 C and which are insoluble in common organic solvents. The aqueous solutions do not exhibit inverse solubility with temperature or concentration. They show low eye and skin irritation and a very low degree of toxicity (LD₅₀ greater than 35 g/kg). They have a bland taste, are good foamers with low surface tension, are compatible with inorganic detergent builders, and are biodegradable. They show good functionality in various applications such as detergents, food emulsifiers, cosmetic surfactants, pharmaceutical granulating agents and industrial emulsifiers.     

Detergency and foam studies on linear alkylbenzene sulfonate and secondary alkyl sulfonate

Among anionic surfactants used in detergent products, the sodium salt of linear alkylbenzene sulfonate (NaLAS) is the only surfactant belonging to the aromatic class; the others are aliphatic, e.g., the sodium salt of secondary alkyl sulfonate (NaSAS). We observed earlier that certain conformational changes taking place in aromatic anionic surfactants (NaLAS) upon micellization can be brought about in aliphatic anionic surfactants (NaSAS) by addition of phenol. In this paper we examined how conformational changes at the molecular level translated into macroscopic properties such as foam and detergency. We performed foam and detergency measurements on NaLAS, NaSAS, and NaSAS/phenol systems. Foam behavior of these systems is shown to be dependent only upon calcium ion sensitivities of the surfactants whereas the detergency results have a dependence on conformational changes at the molecular level.     

Kinetics of the hydrolysis of some alkyl bromides in alkaline and neutral media

The kinetics of the hydrolysis of n-amyl bromide and iso-amyl bromide have been studied in alkaline and neutral media at different temperatures in varying ethanol-water mixtures. The substitution and elimination reactions occur simultaneously in alkaline medium, while in neutral medium only substitution reaction occurs. They have been analysed kinetically and given separate rate constants.     

Differential effect of lysophospholipids on activities of human plasma paraoxonase1, either soluble or lipid-bound

Interaction of paraoxonasel (PON1) with lysophospholipids was examined with respect to activity regulation and binding property. Paraoxonase activity of purified PON1 was partially inhibited by palmitoyl-lysophosphatidylglycerol (palmitoyl-lysoPG) and lysophosphatidylinositol (lysoPl), which had a stimulatory effect on arylesterase and diazoxonase activities. The selective inhibition of paraoxonase activity by palmitoyl-lysoPG, characterized by noncompetitiveness and charge interaction, was also observed with HDL-or dimyristoylphosphatidylcholine (DMPC)-bound PON1. Mean-while, lysophosphatidylcholine (lysoPC) stimulated all three activities of purified PON1, although it stimulated DMPC-bound or HDL-bound PON1 to a lesser extent. The stimulatory action of lysophospholipids was observed around their CMC, suggesting that micelle formation of lysophospholpids might be involved in the stimulation of PON1 activity. Presumably in support of this, the tryptophan fluorescence intensity of PON1 was increased by lysophospholipids at concentrations required for the stimulation of PON1 activity. Separately, lysoPC stimulation was less remarkable for DMPC-bound PON1 than for either dimyristoylphosphatidylserine (DMPS)-or dimyristoylphos-phatidylglycerol-bound PON1, suggesting a tight association between PON1 and DMPC. In support of this, the stimulatory role of apolipoprotein A-I was less prominent for DMPC-bound PON1 than for DMPS-bound PON1. Taken together, these data suggest that the inhibition of paraoxonase activity by lysoPG or lysoPI may be due to binding to a site distinct from the active center, whereas the stimulation by lysophospholipid may be ascribed to the micelle formation around the lipid-associable region of PON1.     

Kinetics of the Hydrolysis of some alkyl halides in aqueous ethyl alcohol

A comparison of the rates of substitution and elimination reactions occuring simultaneously in alkaline hydrolysis of n-amyl chloride, isoamyl chloride, n-amyl iodide and n-hexyl iodide at different temperatures and in varying alcohol-water mixtures, has been made. Under the same conditions the rates of solvolysis of these halides have also been reported. In the case of n-amyl halides there is a much larger rate difference between chloride and bromide than between bromide and iodide.     

Reaction between chlorophosphazenes and some alkyl phosphates: Formation of temperature-stable thermosetting materials

The reaction between chlorophosphazenes and triethyl, tri-n-butyl and acid ethyl phosphates has been studied as a means of preparing temperature-stable thermosetting resinous materials. Ethyl or n-butyl chlorides were eliminated (together with hydrogen chloride in the case of acid ethyl phosphate) and thermosetting resinous products were obtained. The products are film forming when stoved in air. Asbestos laminates, which retain up to 64% of their strength when heated to 500 °C for 50 h in air, have been made with the thermosetting resinous products obtained from the reaction between a chlorophosphazene and triethyl or tri-n-butyl phosphates.     

31P nuclear magnetic resonance studies on alkyl phosphate emulsifiers in cosmetic oil-in-water emulsions

Cosmetic oil-in-water emulsions with a stearyl phosphate emulsifier are examined by means of static and dynamic ³¹P nuclear magnetic resonance (NMR) techniques to characterize the molecular properties of the emulsifier in situ. The interfacially bound emulsifier can be deteced by high-resolution NMR spectroscopy, whereas the excess emulsifier exists as a solid lipid phase not detectable by this technique. The emulsions and the emulsifier raw material, consisting of monostearyl phosphate as well as distearly phosphate, are examined by solid state cross polarization magic angle spinning NMR spectroscopy to prove the existence of solid emulsifier phases in the emulsions. By applying dynamic ³¹P NMR methods to the interfacially bound emulsifier, information about the molecular dynamics at the interface is obtained. The results of the T ₁ and T ₂ relaxation time measurements indicate a restricted motion of the molecules that is dependent on the oil droplet size in the emulsions. This is verified by ³¹P NMR pulsed gradient spin echo self-diffusion measurements on emulsions with different droplet sizes. Only about 5 wt% of the total emulsifier used is bound at the interface; the excess forms solid lipid phases. The coverage of the interface seems to be independent of the emulsifier concentration. Only the monoester of the emulsifier raw material shows interfacial activity. Its mobility indicates the two-dimensional environment of the molecules on the surface of the oil droplets.     

Thermodynamic studies on some interpolymer interactions and stability of polycomplexes

Stability constant and related thermodynamic parameters (ΔH° and ΔS°) of a multicomponent intermacromolecular complex consisting of poly(acrylic acid-coacrylamide), poly(methacrylic acid-co-acrylamide) and poly(N-vinylpyrrolidone) have been determined using known methods. A distinct stepwise disintegration of the complex at different temperatures has been observed, and this could be correlated with the stability constant and thermodynamic parameters calculated at various temperatures.     

Fatty acid and positional selectivities of gastric lipase from premature human infants:in vitro studies

Gastric lipase activity in aspirates from premature human infants was tested for fatty acid and positional selectivity using racemic diacid triacylglycerols (TG) as substrates. The resulting free fatty acids and monoacylglycerols (MG) were recovered and analyzed. Octanoic acid (8∶0) and decanoic acid (10∶0) were hydrolyzed with a preference of 61.5∶1 and 2.4∶1 compared to palmitic acid (16∶0) fromrac-16∶0–8∶8∶0 andrac-16∶0–10∶0–10∶0, respectively. The ratio of lauric acid (12∶0) to oleic acid (18∶1) hydrolyzed fromrac-18∶1–12∶0 was 13∶1. Myristic acid (14∶0), 18∶1 and linoleic acid (18∶2) were released at similar rates. These data and the composition of the MG suggest that,in vitro, the lipase is selective for shorter chain fatty acids and for fatty acids on the primary positions of the TG backbone.     

Enzymatic acylation of ether and ester lysophospholipids in rat liver microsomes

The acylation of lysophospholipids by rat liver acyltransferases was studied. A comparison between ester and ether lysophospholipids as substrates revealed large differences in substrate properties. For instance, oleic acid from oleoyl-CoA and arachidonic acid from arachidonoyl-CoA were not incorporated into 1-O-octadecyl-sn-glycero-3-phosphocholine under experimental conditions that allowed an optimal transfer of oleic acid and arachidonic acid to 1-O-palmitoyl-sn-glycero-3-phosphocholine. However, we observed an acyl-CoA-independent transfer of arachidonic acid from 1-O-stearoyl-2-O-arachidonoyl-sn-glycero-3-phosphoinositol to 1-O-octadecyl-sn-glycero-3-phosphocholine.     

双烷基季铵盐的制备与杀菌性能研究

以溴代烷为原料制备了双烷基二甲基溴化铵系列产品。在产品制备的胺化步骤,作者彩和乙醇作为溶剂或加入相转移催化剂,明显缩短了合成时间,使产品双烷基二甲基溴化铵的产率得到了进一步提高。另外针对双烷基二甲茏溴化铵的杀菌性能进行了一系列评价实验,并与１２２７杀菌剂进行了对比。结果表明：双辛基二甲基溴化铵是较理想的杀菌剂,在较低的浓度下（３０ｍｇ／Ｌ）,其对硫酸盐还原菌（ＳＲＢ）及腐生菌（ＴＧＢ）的杀菌率达１     

X-ray diffraction and melting-point studies on some long-chain sulfur-containing acids

Summary X-ray diffraction powder data and melting points have been determined on three series of crystalline long-chain sulfur compounds, namely 11-(n-alkylsulfonyl)-undecanoic acids; 11-(n-alkylsulfinyl) undecanoic acids; and 11-(n-alkylthio) undecanoic acids; where R is a selected alkyl group from methyl through undecyl. In the sulfone series the long spacings increase regularly with the increase in the number of carbon atoms in R. In contrast to unsubstituted longchain fatty acids the odd and even members fall on the same line in the plot of long spacings against carbon atoms in R. As expected, a nonalternation in melting point is observed. In both the sulfoxide and sulfide series two nonparallel straight lines are obtained, one for the even-membered and one for the odd-membered compounds, in the plot of long spacings against carbon atoms in R. As expected, the melting points of the sulfoxides and sulfides show an alternation. Polymorphism is more evident and complicates the interpretations most in the sulfide series and least in the sulfone series. all three series of compounds crystallized as tilted dimers. This is paper IV in the series on “Organic Sulfur Derivatives.” Paper III is by H. Susi, N. H. Koenig, W. E. Parker, and Daniel Swern, Anal. Chem.,30, 443 (1958). Eastern Utilization Research and Development Division, Agricultural Research Service, U. S. Department of Agriculture.