bluuebunny/crossref_metadata_2025 huggingface dataset:
The antifungal activity of some sulphonyl derivatives of isoxazole, pyrazole, thiazole and thiophene
Authors: Goulding Kenneth H. , Yung Kin‐Man , Hall Avice M. , Cremlyn Richard J. W.
Published: November 2006

Fifty‐three heterocyclic sulphonyl derivatives including eight sulphonamides, three sulphonyl azides, nine sulphonohydrazides and twenty sulphonohydrazones of substituted thiophenes, and a smaller range of analogous isoxazoles pryazoles and thiazoles, were tested as potential fungicides in a simple screening procedure against Mucor mucedo, Septoria nodorum, Trichoderma viride, Chaetomium globosum and Aspergillus niger. Several thiophene‐2‐sulphonyl based compounds exhibited a high level of antifungal activity at 100 mg litre−1 against the five test species, especially the mono‐halogen‐substituted sulphonamides and sulphonohydrazines, in which a single chlorine or bromine atom was substituted in the para position of an attached phenyl ring. The most active compound, against all five species of fungus was N‐(4‐chlorophenyl)‐N‐(trichloromethylthio) thiophene‐2‐sulphonamide which had average MIC50 and MIC100 values of 86 and 180 μmol respectively. (MIC50 and MIC100 values are, respectively, the concentrations required to inhibit fungal growth by 50% and to inhibit it totally.) In general, the isoxazole analogues of the thiophene‐2‐sulphonyl compounds exhibited a much lower fungitoxic activity, whilst the pyrazole and thiazole based compounds had little or no activity. Compared with the other results, the considerable activity shown by 4‐[2′‐(3,4‐dichlorobenzylidene)hydrazinosulphonyl]thiophene‐2‐carboxylic acid was unexpected.
Organophosphorus insecticide residues in olives and olive oil
Authors: Ferreira Júlia R. , Taínha António M.
Published: November 2006

In order to check the pre‐harvest intervals established in Portugal for olive trees, residue dissipation studies have been carried out for the organophosphorus insecticides diazinon, dimethoate, methidathion, parathion and phosphamidon. Simul‐taneously with the analyses of the olives, olive oil produced in the laboratory by a mechanical procedure of pressing the olives was also analysed. The analyses were car‐ ried out by gas‐liquid chromatography. Residues found in the fresh olives, sampled at the end of pre‐harvest intervals in force for each of the insecticides, were accept able. However, for diazinon and parathion, unacceptable high residue levels were found in the olive oil. The concentration of methidathion residues in the olive oil was also observed. For dimethoate and phosphamidon, no detectable residues were found in the olive oil, even when the olives were sampled one day after spraying.
Insecticidal activity of the pyrethrins and related compounds. Part XIIIa: Comparison of the effects of a‐substituents in different esters
Authors: Elliott Michael , Janes Norman F. , Khambay Bhupinder P. S. , Pulman David A.
Published: November 2006

The insecticidal activities of esters from a series of alcohols with four different groups (H, ‐CH3, ‐CCH and ‐CN) in the α‐position, and containing different A‐rings or bridging groups, were evaluated. The results show a complex interaction between these two parts of the molecule; the strongest enhancement of activity by some α‐substituents was found in 3‐phenoxybenzyl esters, while other systems responded weakly or even negatively to the substitution.
Synthesis of some acetylenic and halovinyl heterocyclic carbonyl compounds and their activity against some phytopathogenic fungi
Authors: Arnoldi Anna , Betto Eliseo , Bizzozero Nicoletta , Farina Gandolfina , Formigoni Attilio , Galli Remo
Published: November 2006

Twenty‐three acetylenic or halovinyl carbonyl compounds with heterocyclic substituents were synthesised and tested in vivo against eight phytopathogenic fungi of different taxonomic classes. Some of them were fungicidal against Uromyces appendiculatus on Phaseolus vulgaris, though none showed a wide spectrum of activity.
Azomethines of sec‐butylamine for the control of penicillium decay of oranges
Authors: Eckert Joseph W. , Rahm Michael L.
Published: November 2006

Imines, synthesised by the reaction of sec‐butylamine (SBA, 2‐amino‐butane) with pentan‐2‐one, heptan‐2‐one, octan‐2‐one, undecan‐2‐one, benzaldehyde and 2‐furaldehyde, were evaluated as vapour‐phase treatments to prevent the infection of oranges by Penicillium digitatum. All the imines provided decay control equivalent to SBA when they were introduced into the fruit container at a rate equivalent to 16.4 mg SBA litre−1 air volume. The carbonyl compound component of the imines, tested alone at a five‐fold higher rate, did not reduce fruit decay. All the imines were stable in the gaseous state in dry air. The imines of pentan‐2‐one and undecan‐2‐one were hydrolysed rapidly in a humid environment, indicating that their action against P. digitatum was due to the release of SBA into the atmosphere around the fruit. The instability of the imines of the aliphatic ketones makes them unsuitable as generators of SBA in packages. The imines derived from benzaldehyde and 2‐furaldehyde were stable in moist air, but were hydrolysed to a significant degree on moist filter paper, especially at pH < 7. These aromatic imines were absorbed from the atmosphere by the fruit and were hydrolysed rapidly in water, and in a buffer solution that represented the environment in fresh injuries on fruit. Apparently all the imines tested generated SBA in the fruit environment, and this SBA accumulated at potential infection sites, where it prevented the development of decay.
Contemplations and speculations on novel approaches in the control of fungal plant diseases
Authors: Fuchs Adriaan , Davidse Leen C. , De Waard Maarten A. , De Wit Pierre J. G. M.
Published: November 2006

Plant disease control can, in principle, be achieved by direct and indirect methods. Novel approaches in direct plant disease control are illustrated by the group of ergosterol biosynthesis inhibitors. Consideration of their stereochemistry leads to speculations on a more rational design of chiral fungicides, with possibly optimised activity against a wider range of fungi. Studies on the mode of action of ergosterol biosynthesis inhibitors, and of the mechanism of resistance to them in fungi, suggest that these phenomena are not causally related. At least in laboratory mutants, resistance seems to be associated with altered membrane function, which may account for reduced fitness, and, in pathogens, for reduced virulence as well. The results of these studies strengthen the conclusion that knowledge of the modes of action and mechanisms of resistance, at the physiological, biochemical and molecular level, should provide a rationale on which to base the design of new systemic fungicides.

As a matter of more immediate practical importance, the implications of the use of fungicide‐synergist combinations in plant disease control are briefly discussed.

With respect to indirect plant disease control, novel approaches should be directed towards the activation of host resistance. However, prospects seem to be limited for the successful application of alternative chemicals that act on host resistance mechanisms by, for instance, inducing phytoalexin synthesis. Controlled activation of host resistance by localised sensitisation of resistance mechanisms may, however, become a promising new method of plant disease control in the future.
Aspects of carbon metabolism and the prospects for enhancing yields
Authors: Coombs James
Published: November 2006

The productivity of a given area of land depends on the amount of light falling on that area, the area of plant available to intercept the light, and a series of factors reflecting the varying efficiency of partial processes of photosynthesis. These factors include the rate of flux of carbon dioxide into the leaf, photochemical events, carbon fixation, dark respiration, photorespiration, partitioning and other metabolic events which together determine the net assimilation rate. In addition, productivity is decreased by lack of nutrient or water, disease and other stresses induced by the environment. As a result, the efficiency of trapping of solar energy into agricultural products is often less than 1% when expressed in terms of the total incident energy available. This contrasts with a theoretical efficiency of about 10% for carbon dioxide assimilated into carbohydrate, and a potential productivity of about 5% for most temperate plants. On the basis of current knowledge of carbon metabolism, the relative importance of some of the above factors in reducing the high initial rates of carbon assimilation to cause low final yields, are assessed.
A rapid high‐pressure liquid chromatographic method for the determination of carbaryl residues in wheat grain
Authors: Hargreaves Phillip A. , Melksham Kevin J.
Published: November 2006

Carbaryl residues in wheat grain have been determined in methanol extracts using normal‐phase high‐pressure liquid chromatography (h. p. l. c.) with ultraviolet detection. A single‐injection, clean‐up and analysis technique was used to allow more rapid analysis of samples after extraction. A detection limit of 0.1 mg kg−1 in a 50 g sample of wheat was achieved. Recoveries of 86% at the 1 mg kg−1 level and 90‐99% at the 5 mg kg−1 level were obtained for fortified grain samples. Methanol was found to be a superior extractant for carbaryl from wheat when compared with hexane, acetone and dichloromethane. Twelve samples containing aged carbaryl residues were analysed by the h. p. l. c. technique and by a colorimetric procedure which allowed statistical analysis of errors. For the h. p. l. c. method (excluding sampling error), a relative standard deviation of 4.4% was obtained.
Grain protectants for the control of malathion‐resistant insects in stored sorghum
Authors: Bengston Mervyn , Cooper Lynne M. , Davies Richard A. H. , Desmarchelier James M. , Hart Richard H. , Phillips Mervyn P.
Published: November 2006

Duplicate experiments were carried out on bulk sorghum stored in South Queensland and in Central Queensland. Bioassays of treated grain, conducted during 6 months' storage, established that fenitrothion (12 mg kg−1)+ bioresmethrin (1 mg kg−1), and pirimiphos‐methyl (4 mg kg−1)+ carbaryl (8 mg kg−1), controlled typical malathionresistant strains of Sitophilus oryzae (L.), Rhyzopertha dominica (F.), Tribolium castaneum (Herbst), and Ephestia cautella (Walker). Chlorpyrifos‐methyl (10 mg kg−1)+ pyrethrins (1.5 mg kg−1)+ piperonyl butoxide (12 mg kg−1), and fenitrothion (12 mg kg−1)+ (1R)‐phenothrin (1 mg kg−1), also controlled the strains of S. oryzae, T. castaneum and E. cautella, but were only partly effective against R. dominica. Methacrifos (15 mg kg−1) controlled all the tested species except E. cautella. Chemical assays established that the residues and rates of breakdown of these grain protectants on sorghum conformed to the general pattern for other cereal grains; residues from the above treatments were below the individual Maximum Residue Limits recommended by the Codex Alimentarius Commission.
Relationships between lipophilicity and the distribution of non‐ionised chemicals in barley shoots following uptake by the roots
Authors: Briggs Geoffrey G. , Bromilow Richard H. , Evans Avis A. , Williams Mark
Published: November 2006

Determinations were made of the distribution of two series of non‐ionised chemicals, O‐methylcarbamoyloximes and substituted phenylureas, in barley shoots, following uptake by the roots from solution. The concentrations in basal and central shoot sections became constant after 24 to 48 h for all but the most lipophilic chemical studied, and were then greatest for the more lipophilic chemicals. Amounts in the leaves generally increased up to 72 or 96 h, when degradation balanced translocation. The accumulation of chemical in the lower section of shoots can be ascribed to a partitioning process similar to that in roots, the chemical being partitioned between the shoot and the xylem transpiration stream; this uptake could be estimated from the octan‐1‐01/water distribution coefficients, and was predicted to be greatest for compounds for which log Kow=4. 5.
Insecticide application and degradation in sultana grapes grown for drying
Authors: McDonald Garrick , Buchanan Gregory A. , Griffiths Geoffrey R.
Published: November 2006

Four experiments using the insecticides malathion and chlorpyrifos on mature, unharvested and harvested sultana grapes provided information on the efficiency of application and the rate of loss of insecticides, through the phases of preharvest to processing. Unharvested bunches retained 3.5‐8.1% of the active ingredient (a. i.), whereas harvested bunches laid out to dry retained 23% a. i. Insecticide decay was greatest immediately after application, probably due to volatilisation of unbound chemical, but the rate of loss was accelerated by the use of alkaline drying oils which stimulated hydrolytic degradation. Drying oils are conventionally applied to hasten drying. The residue on fruit at the end of drying was generally higher than that on the fresh fruit because of the concentration effect of dehydration. Processing and storage did not alter the residues, probably because the chemical migrated into the fruit and became bound to inert compounds.
Degradation and persistence of gamma‐HCH and chlorpyrifos‐methyl in Ponderosa pine bark
Authors: Page Marion
Published: November 2006

Residues of gamma‐HCH and chlorpyrifos‐methyl in Ponderosa pine bark (Pinus ponderosa Laws.) were determined 7‐300 days after spray treatment, by a rapid extraction method using ethyl acetate and sodium sulphate, and analysis by gasliquid chromatography using either an electron‐capture or nitrogen‐phosphorus detector. The residue data were fitted into a power curve equation, Y = axb, to determine the rates of insecticide disappearance. The half‐life values (μg cm−2), as interpolated from the power curve, indicate that 50% disappearance occurred in 43 (± 9) days for gamma‐HCH and 102 (± 26) days for chlorpyrifos‐methyl. When half‐life values, however, are computed from extrapolated initial deposits, 50% disappearance occurred in 6 (± 1) days for gamma‐HCH and 15 (±4) days for chlorpyrifos‐methyl.
Influence of block and cell size, growing medium and insecticide dose on the behaviour and uptake of phorate by lettuce and uptake of carbofuran and chlorfenvinphos by calabrese
Authors: Suett David L. , Whitfield Christine E.
Published: November 2006

Phorate residues in peat blocks and lettuce were determined following incorporation of the insecticide into different block and ‘Speedling’ cell sizes. Between‐block variability was influenced little by block size. Phorate oxidation was most extensive in the largest blocks containing the smallest dose. Total residue concentrations in the lettuce declined from the time of planting to harvest, although accumulation of insecticide continued and was related more to dose than to block or cell size. Residues in the lettuce at harvest exceeded the proposed maximum limit of 0.2 mg kg−1 in some treatments. Residues at planting comprised mainly the parent sulphoxide and sulphone, but by harvest, the oxygen analogue sulphoxide and sulphone predominated. Lettuce weight was not influenced by dose but was related directly to block size.

Carbofuran and chlorfenvinphos residues were determined in calabrese sown into two sizes of blocks. At planting time, carbofuran residue concentrations were 100 times greater than those of chlorfenvinphos but residues of both insecticides in the mature heads were < 0.01 mg kg−1. Seedling weights in both sowings declined with increasing concentrations of the insecticides.

It was concluded that manipulations of block size and the dose of insecticide need to be evaluated for individual insecticide/crop combinations to exploit the technique fully.
Phloem transport of xenobiotics in Ricinus communis var. Gibsonii
Authors: Chamberlain Keith , Burrell Michael M. , Butcher Dennis N. , White Jean C.
Published: November 2006

Whole plants of Ricinus communis var. Gibsonii were used to study the mobility of some xenobiotics in the phloem. Solutions of 14C‐ or 35S‐labelled test compounds were introduced directly into the hollow petiole of a leaf that was exporting assimilates. Translocation was monitored by collecting phloem exudate from an incision in the stem bark beneath the treated leaf. Using [3H]sucrose as an internal standard, qualitative and quantitative results were obtained for a variety of model compounds, including herbicides, fungicides and a nematicide.
The fungicidal activity of substituted 1, 4‐naphthoquinones. Part 1: Alkylthio and arylthio derivatives
Authors: Clark Nigel G.
Published: November 2006

Some symmetrical and unsymmetrical 2, 3‐bis(arylthio)‐1, 4‐naphthoquinones have been synthesised and assayed against Botrytis cinerea, Cladosporium fulvum and Venturia inaequalis. With the surprising exception of the 2, 3‐bis(4‐chlorophenylthio) derivative, the compounds were essentially inactive. The 2‐phenylthio and lower 2‐alkylthio derivatives showed a high level of activity, which was absent in the 2‐pentylthio and higher homologues.
Biochemical aspects of the fungitoxic and growth regulatory action of fenarimol and other pyrimidin‐5‐ylmethanols
Authors: Sisler Hugh D. , Ragsdale Nancy N. , Waterfield Willard F.
Published: November 2006

The C‐14 demethylation of the sterols, dependent on cytochrome P‐450, and the C‐22(23) desaturation of sterols are reactions in the ergosterol biosynthesis pathway that are regarded as primary target sites in the toxicity of fungicides of the pyrimidin‐5‐ylmethanol type. Currently, there is no evidence for target sites in other pathways of comparable sensitivity, although the failure of added ergosterol to reverse the fungitoxicity suggests the existence of such sites. The mitochondrial respiratory systems in Ustilago maydis and Aspergillus nidulans are insensitive to this type of fungicide and are not regarded as primary targets of fungitoxicity in these organisms. Appreciable evidence indicates that the primary targets in higher plant growth regulation are reactions, dependent on cytochrome P‐450, that assist in the conversion of kaurene to kaurenoic acid in the gibberellin (GA) biosynthesis pathway. Growth retardation by high concentrations of pyrimidin‐5‐ylmethanols, which is not reversable by GA, apparently involves action at sites outside the GA biosynthesis pathway. The data derived from various studies of the mechanisms of fungitoxicity and growth regulation suggest that any undetected primary targets of the pyrimidin‐5‐ylmethanols are likely to be haem enzymes, similar to the cytochrome P‐450 involved in sterol C‐14 demethylation.
Effects of fungicides on apple crown rot caused by Phytophthora cactorum
Authors: Utkhede Rajeshwar S.
Published: November 2006

The mycelial growth of Phytophthora cactorum on corn meal agar was completely inhibited by metalaxyl or mancozeb at 50 or 100 μg ml−1, but not by fosetyl‐aluminium at the same concentrations. Soil drenches with metalaxyl, followed by metalaxyl+mancozeb, around the base of naturally infected trees under orchard conditions, prevented the growth of P. cactorum in the infected bark of the tree. Soil drenchs with metalaxyl, followed by metalaxyl+mancozeb, also prevented the infection of apple trees with P. cactorum under orchard conditions. The trunk circumference and spur length were not significantly affected by any of the fungicide treatments in all the trials over 2 years, except in one of the four orchards used in the study. Soil drench with metalaxyl alone, or followed by metalaxyl+mancozeb, may provide an effective control method for crown rot of apple trees.
Degradation of dicarboximidic fungicides in wine
Authors: Cabras Paalo , Meloní Marco , Piri Filippo M. , Pirisi Renzo
Published: November 2006

The degradation of some dicarboximidic fungicides (chlozolinate, iprodione, procymidone and vinclozolin) has been studied in wine at pH values of 3.0 and 4.0, at 30°. The kinetic data obtained by observing the disappearance of the active ingredient (3.0 mg kg−1) showed the pseudo first‐order rate constants to be higher at pH 4.0 than at 3.0, with a trend for the values to be in the order: chlozolinate > vinclozolin > procymidone > iprodione. 3, 5‐Dichloroaniline was not detected as a degradation product of any of the compounds. Chlozolinate and vinclozolin in wine each yielded a major metabolite, the structures of which are proposed.
Chemical structure‐fungicidal activity relationships in substituted morpholines
Authors: Pommer Ernst‐Heinrich
Published: November 2006

By the N‐substitution of morpholine with alkyl or cycloalkyl groups containing 12 to 13 carbon atoms, compounds were obtained with good fungicidal activity, in particular, against powdery mildew in barley. An increase in activity was achieved when the carbon atoms in the heterocyclic ring bore one or two methyl groups, the 2,6‐combination being preferred. In the case of sterically different substances, no difference in activity was observed between the cis‐ and trans‐forms. Substituted arylalkyl amines, in which the aromatic ring and the alkylene chain were substituted appropriately, showed very good activity against powdery mildew in wheat and barley, as well as against cereal rust fungi. Steric conditions also play an important role with this type of molecule, as has been proved by detailed investigations on isomers with different configurations in the morpholine moiety, in the alkylene intermediate chain, and in the carbocycle.
A Novel 1D Coordination Polymer [Pb(phen)(μ‐N3)(μ‐NO3)]n with the First Pb2‐(μ‐N3)2 Unit (phen = 1,10‐phenanthroline)
Authors: Marandi Farzin , Mirtamizdoust Babak , Soudi Ali A. , Yilmaz Veysel T. , Kazak Canan
Published: November 2006

A novel 1D polymeric lead(II) complex containing the first Pb2‐(μ‐N3)2 motif, [Pb(phen)(μ‐N3)(μ‐NO3)]n (phen = 1,10‐phenanthroline), has been synthesized and characterized. The single‐crystal X‐ray data showed the coordination number of Pb2+ ions to be eight (PbN4O4) with the Pb2+ ions having “stereo‐chemically active” electron lone pairs; the coordination sphere is hemidirected. The chains interact with each other via π‐π interactions to create a 3D framework.
Artificial rearing of infant rats on milk formula deficient in n‐3 essential fatty acids: A rapid method for the production of experimental n‐3 deficiency
Authors: Ward Glenn , Woods James , Reyzer Michelle , Salem Norman
Published: November 2006

Research into the function of docosahexaenoic acid (DHA; 22:6n‐3), the predominant polyunsaturated fatty acid (PUFA) in the central nervous system (CNS), is often hindered by the difficulty in obtaining dramatic experimental decreases in DHA in the brain and retina of laboratory rats. In this study, the artificial rearing procedure, whereby infant rats are removed from their mothers, gastrostomized, and fed synthetic formula, was used in an attempt to produce rapid changes in CNS levels of DHA. Female rats were raised, from day 4–5 of life, on one of two formulas—one containing the essential fatty acids of both the n‐6 and n‐3 series in proportions approximately equal to those of rat milk, and the other containing high levels of 18:2n‐6 but very little n‐3 fatty acid. At weaning, both groups were given AIN‐76A diets modified so that the PUFA content resembled that of the preweaning formula. At eight weeks of age, the n‐3‐deficient group exhibited decreases of more than 50% in total DHA content in the brain, accompanied by increases in arachidonic acid (AA) (20:4n‐6) and, especially, docosapentaenoic acid (22:5n‐6). Other artificially‐reared rats were mated and their offspring were also maintained on the respective diets. In spite of the fact that they had been reared artificially, the rats mated successfully and reared litters with no obvious abnormalities. At both ten days of age and again at eight weeks, offspring of the n‐3‐deficient mothers exhibited decreases of more than 90% in total DHA content. Again, the long‐chain n‐6 PUFA increased proportionately so that total PUFA levels in the brain were not lower. As these differences are greater than those commonly reported, even after 2–3 generations of normal dietary deprivation in prodents, this procedure may be an important tool in the study of the effects of n‐3 deficiency on neural development and, subsequently, of the function of DHA in nervous tissue.
Chronic administration of eicosapentaenoic acid and docosahexaenoic acid as ethyl esters reduced plasma cholesterol and changed the fatty acid composition in rat blood and organs
Authors: Frøyland Livar , Vaagenes Hege , Asiedu Daniel K. , Garras Alexis , Lie Øyvind , Berge Rolf K.
Published: November 2006

Fish oils rich in n‐3 fatty acids have been shown to decrease plasma lipid levels, but the underlying mechanism has not yet been elucidated. This investigation was performed in order to further clarify the effects of purified ethyl esters of eicosapentaenoic acid (EPA‐EE) and docosahexaenoic acid (DHA‐EE) on lipid metabolism in rats. The animals were fed EPA‐EE, DHA‐EE, palmitic acid, or corn oil (1 g/kg/d) by orogastric intubation along with a chow background diet for three months. At the end the animals were sacrificed. Plasma and liver lipids were measured, as well as lipid‐related enzyme activities and mRNA levels. The fatty acid composition of plasma and different tissues was also determined. This study shows that, compared to the corn oil control, EPA‐EE and DHA‐EE lowered plasma cholesterol level, whereas only EPA‐EE lowered the amount of plasma triacylglycerol. In liver peroxisomes, both EE preparations increased fatty acyl‐CoA oxidase FAO activities, and neither altered 3‐hydroxy‐3‐methylglutaryl (HMG)‐CoA reductase activities. In liver microsomes, EPA‐EE raised HMG‐CoA reductase and acyl‐CoAicholesterol acyltransferase activities, whereas DHA‐EE lowered the former and did not affect the latter. Neither product altered mRNA levels for HMG‐CoA reductase, low density lipoprotein‐receptor, or low density lipoprotein‐receptor related protein. EPA‐EE lowered plasma triacylglycerol, reflecting lowered very low density lipoprotein secretion, thus the cholesterol lowering effect in EPA‐EE‐treated rats may be secondary to the hypotriacylglycerolemic effect. An inhibition of HMG‐CoA reductase activity in DHA‐EE treated rats may contribute to the hypocholesterolemic effect. The present study reports that 20∶5n‐3, and not 22∶6n‐3, is the fatty acid primarily responsible for the triacylglycerol lowering effect of fish oil. Finally, 20∶5n‐3 was not converted to 22∶6n‐3, whereas retroconversion of 22∶6n‐3 to 20∶5n‐3 was observed.
Stereospecific analysis of triacylglycerols rich in long‐chain polyunsaturated fatty acids
Authors: Myher J. J. , Kuksis A. , Geher K. , Park P. W. , Diersen‐Schade D. A.
Published: November 2006

Six oils of marine, algal, and microbial origin were analyzed for stereospecific distribution of component fatty acids. The general procedure involved preparation ofsn‐1,2‐(2,3)‐diacylglycerols by partial deacylation with ethylmagnesium bromide or pancreatic lipase, separation of X‐1,3‐ andsn‐1,2(2,3)‐diacylglycerols by borate thin‐layer chromatography, resolution of thesn‐1,2‐ andsn‐2,3‐enantiomers by chiral phase high‐performance liquid chromatography following preparation of dinitrophenylurethane derivatives, and determination of the fatty acid composition by gas chromatography. Unexpected complications arose during a stereospecific analysis of triacylglycerols containing over 33% of either 20∶4 or 22∶6 fatty acids. Thesn‐1,2(2,3)‐diacylglycerols made up of two long‐chain polyunsaturated acids migrated with the X‐1,3‐diacylglycerols and required separate chiral phase resolution. Furthermore, the enzymatic method yieldedsn‐1,2(2,3)‐diacylglycerols, overrepresenting the polyenoic species due to their relative resistance to lipolysis, but prolonged digestion yielded correct composition for the 2‐monoacylglycerols. The final positional distribution of the fatty acids was established by pooling and normalizing the data from subfractions obtained by norman‐ and chiral‐phase separation of diacylglycerols. The molecular species of X‐1,3‐,sn‐1,2‐ andsn‐2,3‐diacylglycerol dinitrophenylurethanes were identified by chiral‐phase liquid chromatography/mass spectrometry with electrospray ionization, which demonstrated a preferential association of the paired long‐chain acids with thesn‐1,2‐ andsn‐2,3‐diacylglycerol isomers.
Platelet and aorta arachidonic and eicosapentaenoic acid levels andin vitro eicosanoid production in rats fed high‐fat diets
Authors: Sanigorski Andrew J. , Sinclair Andrew J. , Hamazaki Tomohito
Published: November 2006

There is a significant interest in the interrelationship between long‐chain n‐3, and n‐6 fatty acids due to their ability to modulate eicosanoid production. In general, the intake of arachidonic acid (AA) results in enhanced eicosanoid production, whereas n‐3 polyunsaturated fatty acids (PUFA) decrease the production of eicosanoids from AA. The purpose of this study was to investigate whether the effects of dietary AA on eicosanoid production in the rat were correlated with the AA and EPA levels in platelets and aorta (eicosanoid‐producing tissues). Four groups of male Sprague‐Dawley rats were fed a highfat diet enriched with eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) (approximately 100 mg/day of EPA+DHA) for 24 d. During the last 10 d, the four groups were orally supplemented with 0,30,60, and 90 mg/day of ethyl arachidonate. A further group of rats was fed a control diet (without longchain n‐3 PUFA) for 24 d.In vitro aorta prostacyclin (PGI2) production, serum thromboxane A2 (TxA2) production and plasma, and platelet and aorta phospholipid (PL) fatty acids were measured. Enriching the diet with n‐3 PUFA resulted in significant reductions in tissue AA levels and an increase in the n‐3 PUFA, particularly EPA. On this diet, the AA to EPA ratio was 1:1 in platelet PL, and it was 2:1 in the aorta PL. There were significant decreases in thein vitro PGI2 and TxA2 production compared with the control animals. The inclusion of AA in the diet resulted in marked increases in AA levels in the platelet and aorta PL with corresponding decreases in EPA. The lowest dose of AA (30 mg/rat) reversed the effects of 100 mg/day of n‐3 PUFA on AA levels in platelet and aortic PL and onin vitro aorta PGI2 and serum TxA2 production. The dietary AA caused a differential (twofold) increase in TxA2 relative to PGI2 for all three levels of AA supplementation. There were greater changes in the levels of AA and/or EPA in platelet PL compared with the aorta PL, which might have accounted for the differential effects of these PUFA on thromboxane production compared with PGI2 production in this study.
Differential alterations of ethanolamine and choline phosphoglyceride metabolism by clofibrate and retinoic acid in human fibroblasts are not mediated by phorbol ester‐sensitive protein kinase C
Authors: Mandla Suzan G. , Byers David M. , Ridgway Neale D. , Cook Harold W.
Published: November 2006

Peroxisomal proliferators and retinoids have been reported to interact to regulate lipid metabolism, particularly β‐oxidation of fatty acids. Based on postulated interactions of these agents at the levels of receptors and response elements, we examined whether interactions exist between the peroxisomal proliferator, clofibrate (CLF), and retinoic acid (RA) in modulation of phospholipid turnover in cultured human skin fibroblasts. Treatment of cultured cells with either 25 μM CLF or 1 μM RA alone decreased [14C]ethanolamine incorporation into ethanolamine phosphoglycerides (EPG) by 20–30%, and simultaneous exposure to both agents resulted in additive inhibition. By contrast, [3H]choline incorporation into phospholipid was stimulated 5–30% by incubation with either agent; when CLF and RA were administered together, the stimulatory effects were additive. Different types of pulse‐chase studies examining effects on uptake, biosynthesis, and degradation of labelled phospholipids indicated stimulation of EPG degradation and inhibition of phosphatidylcholine degradation by CLF; no effect on catabolism of either phospholipid was observed with RA. Combinations of modifiers of protein kinase activity [4β‐12‐O‐tetradecanoylphorbol‐13‐acetate (β‐TPA), 1‐(5‐isoquino‐linesulfonyl)‐2‐methylpiperazine dihydrochloride,N‐(2′‐guanidinoethyl)‐5‐isoquinolinesulfonamide hydrochloride,bis‐indolylmaleimide, staurosporine] indicated that β‐TPA‐responsive protein kinases were not involved. Accordingly, CLF and RA regulate biosynthesis and degradation of ethanolamine and choline phosphoglycerides in cultured skin fibroblasts by different mechanisms that do not involve classical protein kinase C (PKC) isoforms, even though turnover of phospholipids generating lipid activators of PKC occurs.
Sterol specificity of theSaccharomyces cerevisiae ERG6 gene product expressed inEscherichia coli
Authors: Venkatramesh Mylavarapu , Guo De‐an , Harman James G. , Nes W. David
Published: November 2006

TheERG6 gene fromSaccharomyces cerevisiae has been functionally expressed inEscherichia coli, for the first time, yielding a protein that catalyzes the bisubstrate transfer reaction whereby the reactive methyl group from (S)‐adenosyl‐l‐methionine is transferred stereoselectively to C‐24 of the sterol side chain. The structural requirements of sterol in binding and catalysis were similar to the native protein fromS. cerevisiae. Inhibition of biomethylation was observed with fecosterol and ergosterol which suggests that ergosterol may function in wild‐type yeast as a feedback regulator of sterol biosynthesis.
Comparative hypocholesterolemic effects of six vegetable oils in cholesterol‐fed rat
Authors: Fukushima Michihiro , Akiba Shiori , Nakano Masuo
Published: November 2006

The hypocholesterolemic efficacies of various polyunsaturated fatty acids were compared in rats given cholesterol‐enriched diets.Oenothera biennis Linn oil (OBLO, linoleic +γ‐linolenic), sunflower oil (linoleic), palm oil (PLO, oleic+linoleic), soybean oil (linoleic+α‐linolenic), high‐oleic safflower oil (oleic+linoleic), or mixed oil (linoleic+α‐linolenic) was added to the diet at 200 g/kg (20% groups). OBLO was also added at 100 g/kg diet (10% group). The serum total and very low density lipoprotein+intermediate lipoprotein+low density lipoprotein cholesterol concentrations of the 10 and 20% OBLO groups were consistently lower than those in the other groups. The liver cholesterol concentration in the PLO group was lower in all groups. The liver cholesterol concentrations in the 10 and 20% OBLO groups were also lower than in the other groups. There were no significant differences in the fecal neutral sterol and bile acid extraction among groups.
A rapid method for separation of plasma low and high density lipoproteins for tocopherol and carotenoid analyses
Authors: Vogel Silke , Contois John H. , Couch Sarah C. , Lammi‐Keefe Carol J.
Published: November 2006

Ultracentrifugation (UC) is the method most often employed for separation and quantification of lipoproteins. Because this procedure requires expensive laboratory equipment, a large volume of fresh sample and an inordinate amount of time, it may not be ideal for routine clinical/experimental use. The aim of the current study was to evaluate a method which combines selective precipitation (HDL‐P) and immunoseparation (LDL‐I) for the rapid and reliable isolation of high density lipoproteins (HDL) and low density lipoproteins (LDL) specifically for vitamin E and carotenoid determination within these fractions. Cholesterol and triacylglycerol concentrations within the HDL and LDL were also determined to enable expression of vitamin E and carotenoid concentrations per gram of lipid. Isolation of lipoproteins by UC was used as the reference method (HDL‐UC/LDL‐UC). There were no significant differences between methods for α‐and γ‐tocopherol in LDL and HDL. Carotenoids measured in HDL and LDL were comparable between the methods. The exception was higher lutein/zeaxanthin concentration in HDL‐P and LDL‐I compared to HDL‐UC and LDL‐UC, respectively. Additionally, lycopene concentration was significantly lower in LDL‐I compared to LDL‐UC. In comparing vitamin E and carotenoid values in lipoproteins separated from fresh and frozen plasma by the direct method, there was no difference in α‐tocopherol or the majority of carotenoids measured. In conclusion, a combination of selective precipitation and immunoseparation of fresh or frozen plasma for subsequent α‐and γ‐tocopherol analyses provides an accurate and reliable alternative to lipoprotein separation by UC. Additionally, carotenoid concentrations in HDL separated by selective precipitation and analyses of α‐and β‐carotenes and β‐cryptoxanthin in LDL separated by immunoseparation are also reliable, while lycopene and lutein/zeaxanthin concentrations in LDL‐I are not readily comparable to LDL‐UC.
Neutral sterols of sawflies (symphyta): Their relationship to other hymenoptera
Authors: Schiff Nathan M. , Feldlaufer Mark F.
Published: November 2006

To investigate sterol utilization in sawflies, the neutral sterols of four species of sawflies were determined by gas‐liquid chromatography and mass spectrometry, and compared to the respective dietary plant material. Cholesterol was the predominant (55–76%) sterol in all species and stages of sawflies examined. Host plants, however, contained primarily sitosterol (50–88%), along with other 24‐alkylsterols and only 0.5–5.9% cholesterol, indicating that the sawflies examined are capable of dealkylating the C28 and C29 phytosterols in their diet to cholesterol. Comparative sterol metabolism in Hymenoptera is discussed.
Identification of a novel all‐cis‐5,9,12‐Heptadecatrienoic acid in the cellular slime moldPolysphondylium pallidum
Authors: Saito Tamao , Ochiai Hiroshi
Published: November 2006

The all‐cis‐5,9,12‐heptadecatrienoic acid was identified in the cellular slime moldPolysphondylium pallidum. The structural elucidation was accomplished by capillary gas chromatography, argentation thin‐layer chromatography, and gas chromatography/mass spectrometry. This fatty acid has not been reported previously.
A diet containing myristoleic plus palmitoleic acids elevates plasma cholesterol in young growing swine
Authors: Smith Dana R. , Knabe Darrell A. , Russell Cross H. , Smith Stephen B.
Published: November 2006

The objective of this study was to test the effect of a novel fatty acid mixture, enriched with myristoleic and palmitoleic acids, on plasma lipoprotein cholesterol concentrations. Weanling pigs were assigned to one of six groups and each group received a diet differing in fatty acid composition. Diets were fed for 35 days and contained 10 g added cornstarch/100 g (to provide baseline data) or 10 g added fatty acids/100 g. For those diets containing added fatty acids, extracted lipids contained 36% myristoleic plus palmitoleic acid combined (14∶1/16∶1 diet), 52% palmitic acid (16∶0 diet), 51% stearic acid (18∶0 diet), 47% oleic acid (18∶1 diet), or 38% linoleic acid (18∶2 diet). Witht the exception of the cornstarch diet, all diets contained approximately 30% myristic acid. There were no significant differences in weight gain across treatment groups (P=0.22). All diets caused a significant increase in triglycerides and in total, low density lipoprotein, high density lipoprotein, and very low density lipoprotein cholesterol. The increase in total plasma cholesterol from pretreatment values was greatest in pigs fed the 14∶1/16∶1 and 18∶1 diets. However, the increase in low density lipoprotein cholesterol from the pretreatment concentration was greatest in the 14∶1/16∶1‐fed pigs. Increases in very low density lipoprotein cholesterol above pretreatment concentrations were lowest in 16∶0‐fed pigs and greatest in 18∶1‐fed pigs. Dietary fatty acids elicited changes in plasma fatty acids which generally were reflective of the diets, although the 18∶0 diet did not alter plasma fatty acid concentrations and the 16∶0 diet increased plasma 16∶0 only at the end of the study. These results demonstrated that the combination of myristoleic plus palmitoleic acids increased plasma cholesterol in young pigs, suggesting that fatty acid chain length, rather than degree of unsaturation, is primarily responsible for the effects of fatty acids on circulating lipoprotein cholesterol concentrations.
Fatty acid carbon isotope ratios in humans on controlled diets
Authors: Rhee Sue K. , Reed Roberta G. , Brenna J. Thomas
Published: November 2006

Carbon stable isotope ratios for six serum fatty acids (FA) are reported for human subjects on controlled fat diets to determine the range of natural isotope abundance and to demonstrate the leveling effect of a well‐controlled diet. Twenty‐nine subjects were randomly assigned to one of three controlled diets containing high, medium, or low fat. Diets were consumed for 8 wk. Serum samples were collected at baseline (0), 5, 6, 7, and 8 wk. FA were extracted and methylated. Isotope ratios were analyzed by high‐precision gas chromatography combustion‐isotope ratio mass spectrometry. At baseline, mean δ13C for 16:0b, 16:1a, 18:0a, 18:1c, 18:2n−6d, and 20:4n−6bc were −24.1, −21.7, −21.6, −25.6, −29.6, and −25.0%., respectively, with an average standard deviation of 1.9%.. Most δ13C decreased during the diet period and appeared to have stabilized by week 5 at −25.3, −21.9, −22.3, −26.5, −30.1, and −24.5%., respectively. Between‐subject variability decreased from 1.74 to 1.20%. on the controlled diets. Measurement variability was 0.53%.. The within‐subject variability during weeks 5–8 was 0.57%. (range of 0.32–0.84%.), showing a minimum biological fluctuation on controlled diets. There was no diet group effect on δ13C of serum FA. Except for 18:2, the δ13C of experimental diets was lower than that of serum FA, consistent with observations in animals. These data show that carbon isotope ratios stabilize in response to controlled diets within 5 wk, reflecting the isotope ratio of their dietary source, and establish isotope ratio fluctuations for endogenous compounds for future studies.
Sterol utilization and metabolism by Heliothis zea
Authors: Nes W. David , Lopez Monica , Zhou Wen , Guo De‐an , Dowd Patrick F. , Norton Robert A.
Published: November 2006

Heliothis zea (corn earworm), an insect that fails to synthesize sterols de novo, was reared on an artificial diet treated with 18 different sterol supplements. Larvea did not develop on a sterol‐less medium. Δ5‐Sterols with a hydrogen atom, a methylene group, an E‐or Z‐ethylidene group, or an α‐ or β‐ethyl group (cholesterol, ostreasterol, isofucosterol, fucosterol, sitosterol, and clionasterol, respectively) at position C‐24, and Δ5‐sterols doubly substituted in the side chain at C‐24 with an α‐ethyl group and at C‐22 with a double bond (stigmasterol) supported normal larval growth to late‐sixth instar (prepupal: maturity). The major sterol isolated from each of these sterol treatments was cholesterol, suggesting that H. zea operates a typical 24‐dealkylation pathway. The sterol requirement of H. zea could not be met satisfactorily by derivatives of 3β‐cholestanol with a 9β, 19‐cyclopropyl group, gem dimethyl group at C‐4, a Δ5,7‐bond or Δ8‐bond, or by side‐chain modified sterols that possessed a Δ25(27)‐24β‐ethyl group, Δ23(24)‐24‐methyl group, or 24‐ethyl group, or Δ24(25)‐24‐methyl or 24‐ethyl group. The major sterol recovered from the larvae (albeit developmentally arrested larvae) treated with a nonutilizable sterol was the test compound. Sterol absorption was related to the degree of sterol utilization. The most effective sterols absorbed by the insect ranged from 27 to 66 μg per insect, whereas the least effective sterols absorbed by the insect ranged from 0.6 to 6 μg per insect. Competition experiments using different proportions of cholesterol and 24‐dihydrolanosterol (from 9:1 to 1:9 mixtures) indicated that abnormal development of H. zea may be induced on less than a 1 to 1 mixture of utilizable (cholesterol) to nonutilizable (24‐dihydrolanosterol) sterols. The results demonstrate new structural requirements for sterol utilization and metabolism by insects, particularly with respect to the position of double bonds in the side chain and functionalization in the nucleus. The novel sterol specificities observed in this study appear to be associated with the dual role of sterols as membrane inserts (nonmetabolic) and as precursors to the ecdysteroids (metabolic).
Synthesis and molecular modeling: Related approaches to progress in brassinosteroid research
Authors: Brosa Carme , Zamora Ismael , Terricabras Emma , Soca Lídia , Peracaula Rosa , Rodríguez‐Santamarta Carlos
Published: November 2006

In the field of brassinosteroids, which are potent plant growth regulators, we have developed a quantitative structure‐activity relationship study to develop knowledge from a structural point of view and to find out new requirement definitions. This will help identify other suitable active brassinosteroid derivatives with a good activity/synthetic cost ratio for further application in agriculture. The methodology used to achieve this goal represents a multidisciplinary study involving synthesis, molecular modeling calculations, and bioactivity evaluation. The influence of different molecular properties in the bioactivity of a set of synthetic compounds (i.e., molecular electrostatic potential and the ability to form H bonds) is discussed. The molecular electrostatic potential is expressed in terms of the electrostatic Carbó similarity index (Cl) between brassinolide (1) and other brassinosteroids. We have found that the electrostatic charges of the functional groups play an important role in the description of the activity, as evidenced by its good correlation with the Cl in most cases. Deviation from this rule could be explained by the H bonding abilities of some of these compounds, which we believe may play an essential role in binding to the natural receptors.
Women's Barrier Contraceptive Methods: Poised for Change
Authors: Narrigan Deborah
Published: November 2006

Over the past 20 years, the number of women in the United States choosing a cervical barrier contraceptive method has dramatically declined. By 2002, fewer than 3% of women reported using any woman‐initiated barrier method, including the diaphragm, female condom, or cervical cap. At the same time, however, research in infectious diseases indicates that cervical barriers may effectively prevent the transmission of several sexually transmitted infection. This possibility has fueled the recent development of two novel devices. This article examines the seven devices currently available in the United States, comparing their characteristics, efficacy, benefits, and drawbacks. Compared to the diaphragm, the new devices do not offer improved odds of pregnancy prevention, and evidence for their efficacy is sparse. Reasons for the limited acceptance of these methods as contraceptives on one hand—and for interest in their potential for limiting sexually transmitted infections on the other—will also be reviewed. Despite the limited acceptance of cervical barrier methods, midwives and other clinicians should promote their availability as an alternative to other reversible contraceptives.
Providing Quality Care to the Sexual Assault Survivor: Education and Training for Medical Professionals
Authors: Ferguson Cynthia
Published: November 2006

Health care providers who perform sexual assault examinations can assist patients who report experiencing a sexual assault by increasing their knowledge and skills in sexual assault care, and serving as Sexual Assault Response Team (SART) coordinators, or as SART team members, in their communities. With little additional material, this training could be provided as a component of basic midwifery and/or advanced practice nursing education programs. This article reviews the essential steps and required training for conducting sexual assault examinations.