bluuebunny/crossref_metadata_2025 huggingface dataset:
Resistance mechanisms to DDT and transpermethrin in Aedes aegypti
Authors: Brealey Clive J. , Crampton Peter L. , Chadwick Peter R. , Rickett Frank E.
Published: November 2006

Penetration, metabolism and excretion of [14C]DDT and [3H]transpermethrin were studied in three strains of Aedes aegypti L. after topical application of 10 nl of a solution of the insecticide in 2‐ethoxyethanol. The standard susceptible strain was compared with a DDT‐selected strain (BKS) and a permethrin‐selected strain (BKPM). No significant penetration resistance was observed in either resistant strain, but both showed high DDT‐dehydrochlorinase activity which contributed to the DDT resistance. A non‐metabolic factor was also involved. Rates of transpermethrin metabolism were very similar in all three strains and substantially higher internal concentrations of transpermethrin were required to produce toxic effects in both BKS and BKPM mosquitoes. By analogy with other insect species, it is concluded that transpermethrin resistance in these strains is of the kdr type, while the DDT resistance is a mixture of kdr and DDT‐dehydrochlorinase.
Observations on the antisporulant activity of imazalil (enilconazole)
Authors: Van Gestel Jef F. E. , Van De Ven Marie‐Anne A. P.
Published: November 2006

Imazalil, incorporated in a solid nutrient medium, had no effect on the sporulation of Penicillium italicum at concentrations that did not strongly inhibit mycelial growth. However, when the fungus was grown submerged in liquid culture, sporulation of P. italicum appeared to be more affected than vegetative growth; at 33 nM, imazalil completely prevented the formation of penicilli without adverse effects on growth. Imazalil was able to prevent sporulation in the vapour phase as shown by scanning electron microscopy on P. italicum and Aspergillus niger; the vapours of the compound were found to affect different stages of the sporulation process, depending on the timing of the experiment. Thus, in order to show antisporulant activity, imazalil had to reach the target site by means other than migration within the fungus.
Effects of ingested diflubenzuron on the longevity and the peritrophic membrane of adult mealworms (Tenebrio molitor L.)
Authors: Soltani Noureddine
Published: November 2006

When fed to adults of Tenebrio molitor, diflubenzuron reduced the longevity, the weight of the adults and the thickness of the post‐ecdysial adult cuticle. It also affected the production of the peritrophic membrane. The loss of weight and the decrease of longevity of the treated adults may have been because of alterations to the peritrophic membrane, caused by the inhibition of chitin biosynthesis by diflubenzuron.
The fungicidal activity of substituted 1, 4‐naphthoquinones. Part II: Alkoxy, phenoxy and acyloxy derivatives
Authors: Clark Nigel G.
Published: November 2006

A representative group of 1, 4‐naphthoquinone derivatives, bearing alkoxy, phenoxy and acyloxy substitutents in the 2‐position, has been synthesised and assayed against Botrytis cinerea, Cladosporium fulvum and Venturia inaequalis. The alkoxy compounds exhibited moderate activity, which was enhanced by the presence of a 3‐chloro and, to a lesser extent, a 3‐bromo substituent. 2‐Chloro‐3‐phenoxy derivatives were highly active, but diphenoxy compounds were inactive. Acyloxy derivatives possessed only weak activity unless a halogen atom was present in the 3‐position; benzoyloxy compounds, however, were generally poor fungicides.
Comparison of package cushioning materials to protect post‐harvest impact damage to apples
Authors: Jarimopas B. , Singh S. P. , Sayasoonthorn S. , Singh Jagjit
Published: November 2006

Damage to fruits and vegetables continues to be a big challenge as global markets become a reality. Worldwide distribution of sensitive produce is faced with various levels of impacts from shipping and handling. Despite a variety of packaging options available today, bruising damage is commonplace for post‐harvest apples throughout the supply chain. The major sources of bruising are compression, impact or vibration forces. Understanding where these forces occur can help reduce this type of mechanical damage to apples. The purpose of this study was to investigate the impact characteristics of foam net and corrugated board when applied as wrapping for individual apples. Two grades (count numbers 80 and 100) of “Fuji” cultivar apples imported to Thailand from China were studied. A simple ballistic pendulum test device was developed to measure bruise volume to impact energy relationship. A linear relationship for both types of apples was observed. Bruise volume occurrence probability and impact energy relationship fitted by linear regression were created for cushioned and bare apples. Absorbed energy of various cushioning materials was also calculated under compressive forces. Copyright © 2006 John Wiley & Sons, Ltd.
Scaffold‐Hopping: How Far Can You Jump?
Authors: Schneider Gisbert , Schneider Petra , Renner Steffen
Published: November 2006

Finding new isofunctional chemotypes with the aim of identifying new lead candidates remains a challenging task in medicinal chemistry. Different virtual screening techniques have been shown to be useful for this scaffold‐hopping process. We have compiled recent examples of scaffold‐hops that were achieved by virtual screening. Most of these techniques rely on some sort of similarity estimation between known reference molecules and screening compounds, some include receptor‐structure information and scoring of the ligand–receptor interaction. In this review, we discuss current scaffold‐hopping strategies and pinpoint potential future directions. Challenges for future research lie in the identification of an appropriate level of abstraction from an atomistic molecule representation to allow for the detection of isofunctional chemotypes, the rational design of chemotype diversity in screening libraries, and an understanding of the distribution of similarity scores for a given screening library.
Halide Abstraction from Organic Solvents in Reactions of a Copper(I) Alkoxide: Synthesis and Crystal Structures of [Cu5(dppm)(dppm−)2(OtBu)Cl2] and [Cu3(dppm)3Br2][CuBr2]
Authors: Anson Christopher E. , Ponikiewski Lukasz , Rothenberger Alexander
Published: November 2006

The synthesis and structures of the two CuI halide complexes [Cu5(dppm)(dppm−)2(OtBu)Cl2] and [Cu3(dppm)3Br2][CuBr2] (dppm = Ph2PCH2PPh2, dppm− = [Ph2PCHPPh2]−) are reported. The compounds were obtained by treating reaction mixtures of [CuOtBu] and dppm with dichloromethane or dibromomethane.
Structural Systematics of Rare Earth Complexes. XXII 4‐Methylpyridinium Salts of Diverse Complex Aqua/Chloro/Lanthanoid(III) Species
Authors: Semenova Lioubov I. , Skelton Brian W. , White Allan H.
Published: November 2006

4‐Methylpyridinium cations, mpyH+, crystallized with complex aqua/chloro/lanthanoid(III) species for the gamut of the rare earth series, have ‘domains of existence’ defined for the following forms:

The triclinic $P{\bar 1}$ series (mpyH)2[{(H2O)3Cl3Ln(μ‐Cl)(2|2)}2], previously defined for the Ln = La–Nd members (those for La, Pr characterized by full structure determinations);

The triclinic $P{\bar 1}$ series (mpyH)2[(H2O)3LnCl4]Cl, previously defined for the Ln = Eu, Ho members by full structure determinations, is here augmented by the Ln = Nd, Sm examples (full structure determinations, the latter a new ‘light’ Ln extremum);

A new monoclinic C2/c series (mpyH)2[(H2O)4LnCl3]Cl2, defined for the Ln = Er–Yb extrema (full structural characterizations for the Ln = Er, Tm, Yb members); the lanthanoid‐containing entity (which, with the cations, exhibits some disorder) is a neutral molecule of a new type. For the Ln = Lu case, a fully ordered derivative monoclinic C2 form has been obtained in a cell one half the size.

Other types have also been characterized, thus:

For Ln = La, (mpyH)8[{(H2O)3Cl3La(μ‐Cl)(2|2)}2]‐[{(H2O)4Cl2La(μ‐Cl)2La(OH2)2Cl2(μ‐Cl)(2|2)}2]Cl4·6H2O·mpy has been defined by a full structural determination; the binuclear anion is similar to that in (a), albeit with some disorder, with the tetranuclear anion derivative of it.

For Ln = Lu, (mpyH)2[(H2O)5LuCl2]Cl3 is defined by a full structure determination.

For Ln = Y, (mpyH)2[(H2O)7YCl]Cl4 is defined by a full structure determination; here, and in (ii), the complex component is cationic.
Synthese, Charakterisierung und Magnetische Eigenschaften eines tetranuklearen, Thiacalix[4]aren‐stabilisierten Mangankomplexes
Authors: Zeller Jürgen , Hewitt Ian J. , Radius Udo
Published: November 2006

Synthesis, Characterization and Magnetic Properties of a Tetranuclear, Thiacalix[4]aren stabilized Manganese Complex

Synthesis, characterization and magnetic properties of the compound [(TCA)(TCAH)Mn4(acac)] (1) are reported, the first tetranuclear thiacalix[4]aren stabilized manganese complex synthesized under conventional conditions.
Vielseitige Koordinationschemie von Vanadium(V): Substitutionsreaktionen, Umlagerungen und Kondensationsreaktionen von Oxovanadium(V)‐Komplexen des tripodalen Sauerstoffliganden LOMe− = [η5‐(C5H5)Co{P(OMe)2(O)}3]−
Authors: Kläui Wolfgang , Schäfer Stefan , Peters Wilfried , Wunderlich Hartmut
Published: November 2006

Multifaceted Coordination Chemistry of Vanadium(V): Substitution, Rearrangement Reactions, and Condensation Reactions of Oxovanadium(V) Complexes of the Tripodal Oxygen Ligand LOMe− = [η5‐(C5H5)Co{P(OMe)2(O)}3]−

The octahedral oxovanadium(V) complex [V(O)F2LOMe] of the tripodal oxygen ligand LOMe− = [η5‐(C5H5)Co{P(OMe)2(O)}3]− reacts with alcohols and phenol with substitution of one fluoride ligand to form alkoxo complexes [V(O)F(OR)LOMe], R = Me, Et, i‐Prop, Ph. In the presence of water, however, both fluoride ions are substituted and a complex with the composition VO2LOMe can be isolated. The crystal structure shows that the oxo‐bridged trimer [{V(O)(LOMe)O}3] was synthesized. In the presence of BF3 the fluoride ligand in the alkoxo‐complex [V(O)F(OEt)LOMe] can be exchanged for pyridine to yield [V(O)(OEt)pyLOMe]BF4. Analogous attempts to exchange the fluoride ligand for tetrahydrofuran and acetonitrile induces a rearrangement reaction that leads to the vanadium complex [V(O)(LOMe)2]BF4. The crystal structure of this compound has been determined. Its 1H and 31P‐NMR spectra show that it is a highly fluxional vanadium complex at ambient temperature in solution. The two tripodal ligands LOMe− coordinate the vanadium centre as bidentate or tridentate ligands. The exchange bidentate/tridentate becomes slow on the NMR time scale below about 200 K.
Synthesis and Reactivity of 2,2,4,4–Tetrakis(tri–tert–butoxysilanethiolato)–1,3,2,4–dithiadistannetane – Crystal and Molecular Structures of Two Polymorphic Forms
Authors: Kloskowska Magdalena , Konitz Antoni , Wojnowski Wiesław , Becker Barbara
Published: November 2006

The title compound, [Sn(μ–S){SSi(OtBu)3}2]2 (1), containing four–coordinated tin(IV), crystallizes in two polymorphic modifications. The orthorhombic 1a–form has been obtained in the reaction of (tBuO)3SiSH and Et3N with SnCl2, whereas the triclinic 1b–form in the reaction with SnCl4 as substrate. The crystal and molecular structures of both polymorphs (1a as a redetermination) have been determined by a single–crystal X–ray diffraction study at room temperature. The title compound was shown to react with ammonia and ammonia complexes of some d–block metal cations giving products of Sn–S bond cleavage.
Five Coordinated Zinc(II) and Tris‐Chelate Cadmium(II) Complexes with 2,2′‐Diamino‐5,5′‐dimethyl‐4,4′‐bithiazole – Syntheses, Spectroscopic Characterization, and Crystal Structure
Authors: Hosseinian Akram , Mahjoub Ali Reza
Published: November 2006

The new synthesized ligand (DADMBTZ = 2,2′‐diamino‐5,5′‐dimethyl‐4,4′‐bithiazole), which is mentioned in this text, is used for preparing the two new complexes [Zn(DADMBTZ)3](ClO4)2. 0.8MeOH.0.2H2O (1) and [Cd(DADMBTZ)3](ClO4)2 (2). The characterization was done by IR, 1H, 13C NMR spectroscopy, elemental analysis and single crystal X‐ray determination. In reaction with DADMBTZ, zinc(II) and cadmium(II) show different characterization. In 2, to form a tris‐chelate complex with nearly C3 symmetry for coordination polyhedron, DADMBTZ acts as a bidentate ligand. In 1, this difference maybe relevant to small radii of Zn2+ which make one of the DADMBTZ ligands act as a monodentate ligand to form the five coordinated Zn2+ complex. In both 1 and 2 complexes the $\rm ClO^{-}_{4}$ anions are symmetrically different. 1 and 2 complexes form 2‐D and 3‐D networks via N‐H···O and N‐H···N hydrogen bonds, respectively.
Hydrocarbon chain distribution of ether phospholipids of the ascidianHalocynthia roretzi and the sea urchinStrongylocentrotus intermedius
Authors: Jeong Bo Young , Ohshima Toshiaki , Koizumi Chiaki
Published: November 2006

The contents and compositions of the 1‐O‐alk‐1′‐enyl‐2‐acyl, 1‐O‐alkyl‐2‐acyl, and 1,2‐diacyl glycerophospholipids in the muscle and viscera of the ascidianHalocynthia roretzi, and of the gonad of the sea urchinStrongylocentrotus intermedius, which are eaten to some extent in Alaska and in Asia, were analyzed by gas‐liquid chromatography. 1‐O‐Alk‐1′‐enyl‐2‐acyl glycerophospholipids were found in all of the samples, accounting for 64.4–69.0% of the ethanolamine glycerophospholipid (EPL). By contrast, the levels of the 1‐O‐Alk‐1′‐enyl‐2‐acyl choline glycerophospholipids (CPL) were low (3.1–5.7%). CPL was rich in the 1‐O‐alkyl‐2‐acyl subclass amounting to 12.5–23.9% in the ascidian sample. The level of CPL in the sea urchin gonad was extremely high, amounting to 46.1%. The most prominent alkyl chains in thesn‐1 position of CPL from the ascidian muscle were 16∶0 (44.6%), 18∶1 (26.5%), and 18∶0 (10.7%), and of CPL from the sea urchin gonad were 18∶0 (36.2%), 16∶0 (33.0%), and 18∶1 (17.8%). Unusually high levels of odd‐numbered alkyl chains, e.g., 19∶0 andanteiso 17∶0, were detected in the CPL of all samples. The prominent alkenyl chains of EPL were 18∶0 (69.4%), 16∶0 (10.0%), and 18∶1 (8.54%) (not counting the vinyl double bond) for the sea urchin gonad. Relatively high levels of 20∶1 alkenyl chains were also present. The glycerolsn‐2 positions contained high proportions of polyunsaturated fatty acids. Thus, 20∶5n‐3 (43.6%) and 22∶6n‐3 (20.1%) were most abundant in the alkylacyl CPL from the ascidian muscle and 20∶5n‐3 (54.9%) and 20∶4n‐6 (30.1%) in alkylacyl CPL from the sea urchin gonad. Despite a possible interconversion of the alkyl and alkenyl chains of each class of the ether phospholipids, they showed few features in common.
Dietary modulation of phospholipid fatty acid composition and lipoxygenase products in mouse lung homogenates
Authors: Zhang Hongjian , German J. Bruce
Published: November 2006

This study investigated the potential of dietary fats to modulate the arachidonic acid content of mouse lung phospholipids and the formation of lipoxygenase products from arachidonic and eicosapentaenoic acids. Prior to breeding, female mice were fed for five months diets with 10 wt% of either olive oil, safflower oil, fish oil, or linseed oil. The same diets were fed to the females during gestation and to the pups from day 18 to day 42 postpartum. On day 42, the phospholipids were extracted from fresh lung tissue and separated into classes [phosphatidylethanolamine (PE), phosphatidylserine (PS), phosphatidylcholine (PC), and phosphatidylinositol (Pl)] by thin‐layer chromatography. Methyl esters of phospholipid fatty acids and unesterified fatty acids were analyzed by gas chromatography. At comparable dietary n‐3/n‐6 ratios, arachidonic acid was reduced 85 and 75% in lungs from mice fed linseed oil and fish oil, respectively, compared to lungs of safflower oil‐fed mice. Dietary fats affected the proportion of arachidonic acid in phospholipids in the order: PE>PS>PS>Pl. Following incubation of homogenized lung tissue, the total amount of 12‐lipoxygenase products was lowest in lungs from mice fed olive oil, and 12‐hydroxyeicosatetraenoic acid was lowest in incubated lungs from mice fed linseed oil. Comparison of the amounts of lipoxygenase substrate fatty acids in the individual phospholipids with the lipoxygenase products suggested that the major substrate pool for the 12‐lipoxygenase pathway in mouse lung homogenates was PC.
Optimization of the mass spectrometric analysis of triacylglycerols using negative‐ion chemical ionization with ammonia
Authors: Laakso Päivi , Kallio Heikki
Published: November 2006

Conditions for the mass spectrometric analysis of triacylglycerols,via direct exposure probe, with ammonia negative‐ion chemical ionization were optimized. Triacylglycerols were most favorably ionized, using the reactant gas pressure of approximately 8500 mtorr at the ion source temperature of 200°C with the instrumentation used. Abundant [M‐H]− ions were produced under these conditions without the formation of [M+35]− cluster ions, which would interfere with the molecular weight region of triacylglycerols in the spectra. A rapid desorption of the sample from the probe wire is recommended, using a relatively high heating rate (approximately 40 mA s−1), to minimize thermal degradation of unsaturated molecules and the reducing effect of double bonds on the mass spectrometric response of triacylglycerols. Furthermore, the abundance of [M‐H]− ion was enhanced by rapid heating, which we found to be important to improve the sensitivity. The appropriate amount of sample applied to the rhenium wire was in the region of 50–300 ng for one determination, i.e., only a few nanograms of a single triacylglycerol is required for production of a reliable spectrum. The reproducibility of the method was good as demonstrated with standards and a raspberry seed oil sample. The described mass spectrometric method is a fast and potentially useful tool for semiquantitative determination of triacylglycerol mixtures of various fats and oils. The discrimination, caused by differences in molecular size and unsaturation of triacylglycerols with 50 to 56 acyl carbons, was negligible under our optimized ionization conditions, thus, no correction factors were needed. These findings have not yet been verified with instruments in other laboratories. However, the present study shows how the analysis of triacylglycerols can be improved, regardless of the instrument, by optimization of the analytical conditions.
Oxysterols found in opacified cornea of fish
Authors: Adachi Junko , Hojo Keiko , Naito Takeaki , Tatsuno Yoshitsugu
Published: November 2006

We describe a new concept implicating oxidized cholesterol derivatives and very long‐chain fatty acids as possible factors in the development of corneal opacification after death. Corneal tissues, removed from both fresh and stale fish eyes, were examined for cholesterol derivatives and fatty acids after methanolysis of lipids. Cholesta‐3,5‐dien‐7‐one, cholest‐4‐en‐3‐one, hexacosanoic acid, and hexacosenoic acid were identifiedvia gas chromatography/mass spectrometry in opacified corneas, but not in significant amounts in fresh ones. The present study confirmed the presence of lipid hydrolysis and a peroxidation process in the opacified cornea.
Dietary fat alters biliary lipid secretion in the hamster
Authors: Ohshima Akira , Cohen Bertram I. , Ayyad Nariman , Mosbach Erwin H.
Published: November 2006

Dietary fat has been found to alter the incidence of cholesterol gallstones in hamsters: butterfat intensifies while safflower oil reduces lithiasis. We now report how dietary fat affects bile flow and biliary lipid secretion in this model. Male hamsters were fed one of three experimental diets: a control diet (containing 0.3% cholesterol); control diet +4.0% butterfat; or control diet +4.0% safflower oil. After three weeks, bile samples were collected via an external biliary fistula. The endogenous bile acid pool was depleted for 120 min followed by increasing rates of taurocholate infusion for 160 min. Basal secretion of biliary lipids was measured during the bile acid depletion period. Basal bile flow and bile acid output were not significantly different in the three groups. Dietary butterfat increased basal cholesterol output compared to the control diet (0.037 vs. 0.025 μmol/min·kg, respectively); safflower oil did not change cholesterol output (0.027 μmol/min·kg). Hamsters fed butterfat or safflower oil secreted more phospholipid (0.171 and 0.178 μmol/min·kg, respectively) than controls (0.131 μmol/min·kg). The cholesterol/phospholipid output ratio of the butterfat group was higher than the safflower oil group (0.220 vs. 0.153, respectively). Effects of dietary fat on several relationships between bile flow and biliary lipid secretion were analyzed by linear regression using the data for the entire bile collection period (bile acid depletion and taurocholate infusion). Butterfat and safflower oil did not change either bile acid dependent or bile acid independent bile flow. Hamsters fed butterfat had a higher linkage coefficient (slope) of cholesterol vs. bile acid output than the safflower oil group (0.023 vs. 0.009, respectively). The linkage coefficient of phospholipid vs. bile acid output of the butterfat group was higher than the controls (0.278 vs. 0.185, respectively). In summary, butterfat induced a high cholesterol and phospholipid secretion with a high cholesterol/phospholipid output ratio; safflower oil induced a high phospholipid secretion with a low cholesterol/phospholipid output ratio. Butterfat and safflower oil have different effects on biliary lipid secretion. These differences in biliary lipid secretion may explain, in part, how butterfat and safflower oil differ in affecting gallstone formation in hamsters.
Effects of dietary heated fats on rat liver enzyme activity
Authors: Lamboni Courdjo , Perkins Edward G.
Published: November 2006

The objective of this study was to evaluate the effects of dietary heated fats from a commercial deep‐fat frying operation on rat liver enzyme activity. The fats, partially hydrogenated soybean oil (PHSBO) used for four days and for 7 days (7‐DH) for frying foodstuffs in a commercial restaurant, were fed to rats in either free access to food or by pair‐feeding graded doses. All diets were isocaloric and contained 15 g/100 g of diet. Experiments were conducted with control rats fed nonheated (NH) PHSBO diet. Animals fed 7‐DH diet in each set of experiments had larger amounts of cytochromes P450 and b5 and greater activity of NADPH‐cytochrome P450 reductase when compared to controls. The activities of carnitine palmitoyltransferase‐I and isocitrate dehydrogenase were significantly lower in rats fed test diets in comparison to controls. A significantly depressed activity of glucose 6‐phosphate dehydrogenase was also noticed for these animals when compared to those fed NH. In addition, liver and microsomal protein concentrations were significantly greater in rats fed the used oils in comparison to controls, and liver glycogen was significantly lower.
The chemistry and antioxidant properties of tocopherols and tocotrienols
Authors: Kamal‐Eldin Afaf , Appelqvist Lars‐Åke
Published: November 2006

This article is a review of the fundamental chemistry of the tocopherols and tocotrienols relevant to their antioxidant action. Despite the general agreement that α‐tocopherol is the most efficient antioxidant and vitamin E homologuein vivo, there was always a considerable discrepancy in its “absolute” and “relative” antioxidant effectivenessin vitro, especially when compared to γ‐tocopherol. Many chemical, physical, biochemical, physicochemical, and other factors seem responsible for the observed discrepancy between the relative antioxidant potencies of the tocopherolsin vivo andin vitro. This paper aims at highlighting some possible reasons for the observed differences between the tocopherols (α‐, β‐, γ‐, and δ‐) in relation to their interactions with the important chemical species involved in lipid peroxidation, specifically trace metal ions, singlet oxygen, nitrogen oxides, and antioxidant synergists. Although literature reports related to the chemistry of the tocotrienols are quite meager, they also were included in the discussion in virtue of their structural and functional resemblance to the tocopherols.
Effect of α‐tocopherol and Trolox on the decomposition of methyl linoleate hydroperoxides
Authors: Hopia Anu , Huang Shu‐Wen , Frankel Edwin N.
Published: November 2006

To clarify the mechanisms of antioxidant action, the effect of α‐tocopherol and its water‐soluble carboxylic acid derivative, Trolox, was studied on the decomposition of methyl linoleate hydroperoxides (MeLoOOH). Decomposition rate and the distribution of autoxidation products formed from MeLoOOH were followed by analyzing the volatile and nonvolatile products by static headspace gas chromatography and normal‐phase high‐performance liquid chromatography, respectively. Both α‐tocopherol and Trolox markedly inhibited the decomposition of MeLoOOH in a concentration‐dependent way. In the absence of antioxidants, MeLoOOH was completely decomposed after incubation for 48 h at 60°C, and in the presence of equal molar concentration of antioxidants only 6–7% of initial MeLoOOH was decomposed even after 280 h of incubation. MeLoOOH produced 1.2% methyl linoleate hydroxy compounds (MeLoOH) in the presence of α‐tocopherol and 3.8% in the presence of Trolox. Both antioxidants inhibited the formation of volatile decomposition products and the formation of ketodiene compounds. The hydroxy compounds may be formed by the reaction of alkoxy radical and hydrogen donating antioxidants. Conversion of MeLoOOH into stable MeLoOH demonstrated that the antioxidants α‐tocopherol and Trolox trap alkoxyl radicals by H‐donation.
Purification and characterization of aPenicillium sp. lipase which discriminates against diglycerides
Authors: Gulomova Komola , Ziomek Edmund , Schrag Joseph D. , Davranov Kahramon , Cygler Miroslaw
Published: November 2006

A lipase was isolated fromPenicillium sp. strain UZLM‐4 and characterized. This lipase has a molecular weight of 27,344 (determined by mass spectrometry) and hydrolyzes triglycerides in preference to mono‐ and diglyceride substrates. Among various triglyceride substrates, tributyrin is hydrolyzed about four times faster than any other tested. The lipase has a preference for hydrolysis at the 1,3 positions of the lipids and shows a weak stereoselectivity for the S enantiomer. Unlike most other lipases, this lipase is stable and has a high activity at low surface pressures (5–10 mN/m).
Studies on phospholipid biosynthesis in hepatocytes from alcoholic rats by using radiolabeled exogenous precursors
Authors: Carrasco M. P. , Sanchez‐Amate M. C. , Segovia J. L. , Marco C.
Published: November 2006

We have studied the synthesis of phospholipids in hepatocytes isolated from chronically ethanol‐treated rats by using isotopically labelled serine, ethanolamine, and choline as exogenous precursors. Our results demonstrate that ethanol induces specific effects on the biosynthesis of phosphatidyl‐ethanolamine and phosphatidylcholinevia CDP‐derivatives and also on the synthesis of phosphatidylserinevia the Ca++‐dependent base‐exchange reaction. Thus, the synthesis of phosphatidylethanolamine from [3‐H]ethanolamine and the incorporation of [3H]serine into phosphatidylserine were clearly higher in hepatocytes from ethanol‐treated rats compared to controls. The synthesis of phosphatidylcholine from [methyl‐14C] choline, on the other hand, decreased markedly, suggesting a specific inhibition of cholinephosphotransferase activity. We have also demonstrated that the phosphatidylcholine levels are markedly decreased in hepatocytes isolated from chronically ethanol‐treated rats as a consequence of the lower phosphatidylcholine biosynthesis. The decrease in the incorporation of radioactivity from choline to betaine, which we also found, is interpreted as being the result of a higher use of betaine as methyl donor instead of methionine to maintain the hepaticS‐adenosylmethionine levels in chronic alcoholism.
Estimation of polyunsaturated fatty acid content in lipids of aquatic organisms using thin‐layer chromatography on a plain silica gel plate
Authors: Nakamura Takashi , Fukuda Masahiro , Tanaka Ryusuke
Published: November 2006

We have designed a rapid method for the separation of polyunsaturated fatty acids (PUFA, ≥trienes) from non‐PUFA, and for estimation of total amounts of PUFA in lipids of aquatic organisms. Lipids from thirty‐one species, including marine and fresh water fishes, shell fishes, marine algae, and other aquatic animals, and from terrestrial organisms, were transesterified with sodium methoxide in methanol. The resulting fatty acid methyl esters were separated by thin‐layer chromatography on commercially available plain silica gel plates with a developing solvent ofn‐hexane/ethyl ether/acetic acid (95∶5∶1, by vol). All of the methyl esters from aquatic organisms tested separated into two spots, whereas those from terrestrial sources, except for linseed oil, showed a single unresolved spot. The upper and lower spots were scraped separately from the plate, and their fatty acid compositions were determined by gas‐liquid chromatography. The lower spot was composed of PUFA having more than two double bonds, whereas components of the upper spot were saturated, monoenoic, and the greater part of the dienoic fatty acids. When the spots on the silica gel plate were stained with Coomassie brilliant blue, the amounts of PUFA in aquatic organisms could be estimated satisfactorily using a scanning densitometer.
Increased hepatic synthesis and accumulation of plasma apolipoprotein B100 in copper‐deficient rats does not result from modification in apolipoprotein B mRNA editing
Authors: Nassir Fatiha , Giannoni Federico , Mazur Andrzej , Rayssiguier Yves , Davidson Nicholas O.
Published: November 2006

Experimentally induced copper deficiency in the rat results in increased plasma apolipoprotein B100 (apo B100) concentration in association with increased hepatic apo B100 synthesis. This enhancement of apo B100 synthesis and plasma accumulation accounts for the rise of plasma low density lipoprotein in these animals. In the present study, we have investigated if the selective increase in hepatic apo B100 synthesis is accounted for by changes in apo B mRNA editing. Reverse transcription coupled with polymerase chain reaction amplification and primer extension analysis of apo B cDNA revealed no differences in apo B mRNA editing in either the liver or small intestine between control and copper‐deficient rats. We speculate that the increase in apo B100 synthesis in the liver of copper‐deficient rats reflects posttranslational alterations in gene expression accompanying changes in very low density lipoprotein assembly and secretion.
Effect of dietary n‐9 eicosatrienoic acid on the fatty acid composition of plasma lipid fractions and tissue phospholipids
Authors: Cleland L. G. , Neumann M. A. , Gibson R. A. , Hamazaki T. , Akimoto K. , James M. J.
Published: November 2006

n‐9 Eicosatrienoic acid (ETrA), also known as Mead acid, is a minor fatty acid in essential fatty acid (EFA)‐sufficient healthy subjects but is found at increased levels in EFA deficiency. This study examined the influence of dietary ETrA from a biological source on plasma and tissue ETrA. A synthetic fat‐free diet was prepared to which was added Mut 48 oil which contains 19% ETrA (wt%) as well as other n‐9 fatty acids. Blends of vegetable oils were used to achieve overall diets with 5% fat (wt%) and varying amounts of ETrA at two different dietary levels of linoleic acid (LA), approximately 4.4 and 19% of total fatty acids. These diets were fed to 5‐week‐old Dark Agouti rats for four weeks. Plasma lipid fractions and liver, spleen, and peritoneal exudate (PE) cells were analyzed for fatty acid composition. ETrA was present at up to 20% total fatty acids in plasma triglyceride, cholesterol ester, and phospholipid fractions. ETrA also accumulated to substantial levels in phospholipids of liver and spleen (up to 15% of total fatty acids) and PE cells (up to 11%). ETrA was found in plasma and tissue phospholipids in proportion to the amount of ETrA present in the diet. The incorporation was reduced in diets with higher LA content compared to diets containing similar amounts of ETrA but lower LA. All rats remained apparently healthy, and histological survey of major organs revealed no abnormality. While the long‐term implications for health of ingestion of diets rich in ETrA remain to be established, rats appear to tolerate high levels of dietary ETrA without adverse effects. Dietary enrichment with ETrA warrants further investigation for possible beneficial effects in models of inflammation and autoimmunity, as well as in other conditions in which mediators derived from n‐6 fatty acids can affect homeostasis adversely.
Vitamin E inhibits fish oil‐induced hyperlipidemia and tissue lipid peroxidation in hamsters
Authors: Kubow Stan , Goyette Nathalie , Kermasha Selim , Stewart‐Phillip Jean , Koski Kristine G.
Published: November 2006

Previous research has linked hyperlipidemia with increased serum concentrations of lipid peroxidation products; however, a specific association between diet‐induced oxidative stress and hyperlipidemia has not been studied. In the present study, the relationship between tissue lipid peroxidation and hyperlipidemia induced by ingestion of fish oil was examined. In Experiment 1, male Golden Syrian hamsters were fed semipurified diets composed of 1.6 wt% safflower oil plus 15.0 wt% of either butterfat (BF), safflower oil (SAFF), or high‐cholesterol menhaden oil [MHO(H‐CHOL)] semipurified diets for 27 d. The cholesterol contents of the diets were adjusted to 0.088%. The MHO(H‐CHOL)‐fed hamsters exhibited higher serum concentrations of total cholesterol, triglycerides, apolipoprotein B, and lipid peroxides when compared to the BF and SAFF diet groups. In a further study (Experiment 2), hamsters were fed for 27 d three dietary treatments: (i) MHO(H‐CHOL) with no vitamin E content; (ii) a low‐cholesterol menhaden oil containing high concentrations of vitamin E (2.5 mg tocopherol/g oil or dietary concentrations of 375 mg/kg) [MHO(L‐CHOL)+E]; and (iii) the MHO(L‐CHOL+E) with added cholesterol (595 mg/kg) [MHO(L‐CHOL)+CHOL+E] to match the cholesterol content of the MHO(H‐CHOL). The MHO(L‐CHOL)+E and MHO(L‐CHOL)+CHOL+E diet groups showed lower concentrations of serum cholesterol, triglycerides, and hepatic lipid peroxides than the MHO(H‐CHOL)‐treated group. Moreover, in contrast to the hypercholesterolemia caused by the MHO(H‐CHOL) feeding, the MHO(L‐CHOL)+E and MHO(L‐CHOL)+CHOL+ E diets did not show a serum cholesterol‐elevating action. This study supports the hypothesis that oxidative stress in the Syrian hamster could play a causal role in dietary‐induced hyperlipidemia which can be inhibited by high vitamin E intake.
Effect of a synthetic androgen on biliary lipid secretion in the female hamster
Authors: Ohshima Akira , Cohen Bertram I. , Ayyad Nariman , Mosbach Erwin H.
Published: November 2006

This study was designed to elucidate the effect of the synthetic androgen, methyltestosterone, on bile flow and biliary lipid secretion in female hamsters. Animals were divided into four groups and fed the following diets: group 1, lithogenic diet for three weeks; group 2, lithogenic diet+0.05% methyltestosterone for three weeks; group 3, lithogenic diet for six weeks; group 4, lithogenic diet+0.05% methyltestosterone for six weeks. At the end of each experimental period, the hamsters were operated on to establish external biliary fistulas. During the depletion of the endogenous bile acid pool (for two hours), the basal bile flow of group 4 was significantly smaller than that of group 3. Basal bile acid output was significantly lower in the methyltestosterone‐fed groups 2 and 4 than in control groups 1 and 3. In contrast, groups 2 and 4 secreted more cholesterol than groups 1 and 3. Group 4 had a higher ratio of cholesterol output to phospholipid output than group 3. Increasing doses of taurocholate were infused after the bile acid depletion period, and it was found that methyltestosterone did not change the bile acid independent bile flow. The increments in cholesterol or phospholipid output induced per increments of bile acid output (linkage coefficients) were analyzed by linear regression. The methyltestosterone‐fed groups (groups 2 and 4) had a higher linkage coefficient of cholesterol output to bile acid output than the control groups (groups 1 and 3). The linkage coefficients of phospholipid output to bile acid output of groups 2 and 4 were also higher compared to groups 1 and 3. The linkage coefficient of cholesterol output to phospholipid output of group 2 was higher than that of group 1. These results suggest that methyl‐testosterone stimulated the cosecretion mechanism of cholesterol and phospholipid in bile associated with an increasing ratio of cholesterol to phospholipid. In conclusion, the synthetic androgen, methyltestosterone, caused a decrease in basal bile flow and bile acid secretion, and an increase in basal cholesterol secretion and the biliary cholesterol‐to‐phospholipid ratio. These findings explain, in part, how methyltestosterone intensifies the formation of cholesterol gallstones in female hamsters.
Glucosylceramide transfer from lysosomes—the missing link in molecular pathology of glucosylceramidase deficiency: A hypothesis based on existing data
Authors: Elleder M.
Published: November 2006

Gaucher disease (GD), deficiency of acid glucosylceramidase (GlcCer‐ase) is characterized by deficient degradation of beta‐glucosylceramide (GlcCer). It is well known that, in GD, the lysosomal accumulation of uncleaved GlcCer is limited to macrophages, which are gradually converted to storage cells with well known cytology—Gaucher cells (GCs). On the basis of previous studies of the disorder and of a comparison with other lysosomal enzymopathies affecting degradation of the GlcCer‐based glycosphingolipid series, it is hypothesized that in other cell types (i.e. non‐macrophage cells) the uncleaved GlcCer, in GlcCer‐ase deficiency, is transferred to other cell compartments, where it may be processed and even accumulated to various degrees. The consequence of the abnormal extralysosomal load may differ according to the cell type and compartment targeted and may be influenced by genetically determined factors, by a number of acquired conditions, including the current metabolic situation. The sequelae of the uncleaved GlcCer extralysosomal transfer may range from probably innocent or positive stimulatory, to the much more serious, in which it interferes with a variety of cell functions, and in extreme cases, can lead to cell death. This alternative processing of uncleaved GlcCer may help to explain tissue alterations seen in GD that have, so far, resisted explanation based simply on the presence of GCs. Paralysosomal alternative processing may thus go a long way towards filling a long‐standing gap in the understanding of the molecular pathology of the disorder. The impact of this alternative process will most likely be inversely proportional to the level of residual GlcCer‐ase activity. Lysosomal sequestration of GlcCer in these cells is either absent or in those exceptional cases where it does occur, it is exceptional and rudimentary. It is suggested that paralysosomal alternative processing of uncleaved GlcCer is the main target for enzyme replacement therapy. The mechanism responsible for GlcCer transfer remains to be elucidated. It may also help in explaining the so far unclear origin of glucosylsphingosine (GlcSph) and define the mutual relation between these two processes.
Global environmental changes in terrestrial ecosystems. International issues and strategic solutions: introduction
Authors: Hong Sun Kee , Lee John A.
Published: November 2006

Human activities are having major impact on biogeochemical cycles and ecosystems worldwide. Rapid urbanization and changes in rural populations are affecting ecosystems in often‐drastic ways. Ecologists are using long term monitoring and experimental studies to understand and to help mitigate the effects of these changes. The collection of 15 papers in this special volume “global changes in terrestrial ecosystems” describes some of these studies, particularly concentrating on effects on terrestrial ecosystems and landscapes, and demonstrating the importance of understanding the problems at both the multi‐scale and international levels.
Dietary fatty acid profile affects endurance in rats
Authors: Ayre Kerry J. , Hulbert A. J.
Published: November 2006

Typically, athletes are advised to increase their consumption of carbohydrates for energy and, along with the general population, to reduce consumption of saturated fats. It is now recognized that fats are not identical in their influence on metabolism, and we argue that the composition of the polyunsaturated fat component should not be ignored. The aim of this study was to manipulate the dietary fatty acid profile in a high‐carbohydrate diet in order to investigate the effect of dietary polyunsaturates on submaximal endurance performance in rats. Rats were fed one of three isoenergetic diets containing 22 energy percentage (E%) fat for 9 wk. The diets comprised an essential fatty acid‐deficient diet (containing mainly saturated fatty acids); a diet high in n‐6 fatty acids, High n‐6; and a diet enriched with n‐3 fatty acids, High n‐3. Submaximal endurance in rats fed the High n‐3 diet was 44% less than in rats fed the High n‐6 diet (P<0.02). All rats were then fed a standard commercial laboratory diet for a 6‐wk recovery period, and their performances were reevaluated. Although endurance in all groups was lower than at 9 wk, it was again significantly 50% lower in the High n‐3 group than the High n‐6 group (P<0.005). Although n‐3 fats are considered beneficial for cardiovascular health, they appear to reduce endurance times, and their side effects need to be further investigated.
The development of heart failure in patients with stable angina pectoris
Authors: Sutton George C. , Otterstad Jan Erik , Kirwan Bridget‐Anne , Vokó Zoltán , de Brouwer Sophie , Lubsen Jacobus , Poole‐Wilson Philip A. ,   ACTION (A Coronary disease Trial Investigating Outcome with Nifedipine GITS) investigators
Published: November 2006

Background:

To describe the clinical characteristics of patients with stable angina pectoris who develop heart failure and the events preceding its onset.

Methods and results:

Of 7665 patients with stable angina in the ACTION trial, which compared long‐acting nifedipine to placebo, 207 (2.7%) developed heart failure (HF) during a mean follow‐up of 4.9years. Those who developed HF were significantly (P<0.05) older, more often had diabetes, had a more extensive history of cardiovascular disease, lower ejection fractions, a higher serum creatinine and glucose, a lower haemoglobin, and were more often on blood pressure lowering drugs. A cardiac event or an intervention (n=155), a significant non‐cardiac infection (n=19) or poor control of hypertension (n=12) preceded the development of HF in 186/207 cases (90%). There was no obvious precipitating factor in the remaining 21 patients (10%). Myocardial infarction increased the risk of the development of new HF within one week more than 100‐fold. Nifedipine reduced the incidence of HF by 29% (P=0.015).

Conclusions:

The development of heart failure is uncommon in patients with stable angina, and even less so in the absence of an obvious precipitating factor.
Usefulness of bifocal pacing in patients with heart failure and intraventricular conduction delay
Authors: Bulava Alan , Lukl Jan
Published: November 2006

Background:

Bifocal pacing (BFP) has been proposed as a feasible alternative to cardiac resynchronization therapy.

Aim:

To evaluate BFP in patients with severe heart failure and significant intraventricular conduction delay and to compare it with biventricular pacing (BVP).

Methods:

Echocardiographic examination including TDI and invasive measurement of haemodynamics was performed under basal conditions, during BFP and during BVP.

Results:

Fifty patients were included: 29 with ischaemic heart disease (IHD), 21 with idiopathic dilated cardiomyopathy (IDCM). LV dp/dtmax increased during BFP compared to the basal state (13.4%, 95% CI 9.2–17.6%, p<0.0001) and a further increase was achieved during BVP (29.5%, 95% CI 23.7–35.4%, p<0.0001). A significant correlation was found between the distance of the right ventricular apical and outflow tract leads and percentage of dp/dtmax increase in IDCM patients (r=0.72), but not in IHD patients. Interventricular mechanical delay (IVMD) decreased in BFP (43±22 ms vs. 53±31 ms, p=0.006), but BVP produced even shorter IVMD (22±19ms, p<0.0001). In all patients, regional systolic contraction times were significantly shortened, corresponding with prolongation of the respective regional diastolic filling times during both BFP (p<0.05 for all segments) and BVP (p<0.001 for all segments).

Conclusions:

BFP improves LV haemodynamics by decreasing the inter‐ and intraventricular conduction delays. The leads in the right ventricle should be placed at the longest achievable distance. BVP is superior to BFP.
Essure: Hysteroscopic Sterilization
Authors: Hastings‐Tolsma Marie , Nodine Priscilla , Teal Stephanie B.
Published: November 2006

Essure, a new female sterilization method approved by the US Food and Drug Administration, offers women a new option for controlling fertility. The technique is done without an incision, is hormone‐free, and can be performed on an outpatient basis under local anesthesia. There are few or no side effects. It is important for providers to understand how the device works, appropriate candidates for use, and requirements for preplacement and postplacement management.
Ultrasound Assessment of the Endometrium for Irregular Vaginal Bleeding
Authors: McFarlin Barbara L.
Published: November 2006

Irregular vaginal bleeding is a common symptom of women seeking gynecologic care. Etiologies of irregular vaginal bleeding can be classified into the following categories: pregnancy related (retained products of conception, threatened or missed abortion, or ectopic pregnancy), hormonal (disorders of ovulation, menopause, or hormonal contraceptive use), structural (polyps, myomas, or arteriovenous malformation), neoplasm (endometrial cancer), and infection (endometritis). After the history and physical examination, the initial evaluation of irregular vaginal bleeding has traditionally involved an endometrial biopsy. Transvaginal ultrasound has revolutionized the evaluation of the gynecologic ultrasound examination by providing a minimally invasive means to determine the etiology for the bleeding. Transvaginal ultrasound assessment of the endometrial cavity allows treatment to be tailored to the specific cause of irregular vaginal bleeding, thus saving women time, money, and exposure to unnecessary interventions. The purpose of this article is to give the clinician critical information regarding the capabilities of ultrasound to evaluate women with irregular vaginal bleeding.
Help‐Seeking Behaviors of Women with Urinary Incontinence: An Integrative Literature Review
Authors: Koch Laura Hunter
Published: November 2006

Urinary incontinence (UI) affects approximately 17 million American women. Women with UI have reported a lower quality of life than women who do not experience UI. In many cases, UI affects a woman's ability to take part in a variety of recreational and social activities, and has negative psychological effects including depression, anxiety, and frustration. Studies show that fewer than 50% of women with UI discuss their symptoms with their health care provider. Although researchers have examined help‐seeking behaviors in people with UI, few have examined women of all ages with all types of UI. The purpose of this integrative literature review is to summarize the help‐seeking behaviors for UI symptoms among noninstitutionalized women of all ages with all types of UI. Five studies were reviewed. In all of the studies, less than 38% of women sought help for their UI symptoms. Factors affecting help seeking included quality of life scores, perceptions women had regarding the normalcy of UI, and beliefs about treatment options available for the problem. Age, type of UI, severity of UI, and embarrassment were found to be significantly related to help‐seeking in most, but not all of the studies.