bluuebunny/crossref_metadata_2025 huggingface dataset:
Amygdala adenosine A1 receptors have no anticonvulsant effect on piriform cortex-kindled seizures in rat
Authors: Shahabi Parviz , Mirnajafi-Zadeh Javad , Fathollahi Yaghoub , Hoseinmardi Narges , Rezvani Mohammad Ebrahim , Eslami-far Ali
Published: November 2006

Adenosine is an endogenous anticonvulsant that exerts its effects through A1 receptors. As the piriform/amygdala is a critical circuit for limbic seizure propagation, in this study, the role of basolateral amygdala A1 receptors on piriform cortex (PC)-kindled seizures was investigated. Rats were kindled by daily electrical stimulation of PC. In fully kindled animals, bilateral intra-amygdala N6-cyclohexyladenosine (CHA; 10–500 µmol/L, a selective A1 receptor agonist) had no effect on kindled-seizure parameters. However, bilateral intra-amygdala 2% lidocaine (reversal neuronal inhibitor) reduced the kindled seizure severity. There was significant increase in stage 4 latency and decrease in stage 5 duration. Bilateral lesion of basolateral amygdala of kindled animals (by electrical DC current) reduced the kindled seizure severity more dramatically. Our results showed afterdischarge duration, stage 5 duration, and seizure duration were decreased and stage 4 latency increased significantly. In addition, daily intra-amygdala CHA had no significant effect on PC kindling acquisition. Therefore, it may be concluded that although the basolateral amygdala neuronal activity has a critical role in the propagation of epileptic seizures from PC, the amygdala A1 receptors have no role in this regard. On the other hand, amygdala A1 receptors have no anticonvulsant or antiepileptogenic effect on PC-kindled seizures.
Pentoxifylline attenuation of experimental hepatopulmonary syndrome
Authors: Zhang Junlan , Ling Yiqun , Tang Liping , Luo Bao , Chacko Balu K. , Patel Rakesh P. , Fallon Michael B.
Published: November 2006

Hepatopulmonary syndrome (HPS) following rat common bile duct ligation results from pulmonary molecular changes that may be influenced by circulating TNF-α and increased vascular shear stress, through activation of NF-κB or Akt. Increased pulmonary microvascular endothelin B (ETB) receptor and endothelial nitric oxide synthase (eNOS) levels contribute to nitric oxide production and the development of experimental HPS. Pentoxifylline (PTX), a phosphodiesterase and nonspecific TNF-α inhibitor, ameliorates experimental HPS when begun before hepatic injury. However, how PTX influences the molecular events associated with initiation of experimental HPS after liver injury is established is unknown. We assessed the effects of PTX on the molecular and physiological features of HPS in vivo and on shear stress or TNF-α-mediated events in rat pulmonary microvascular endothelial cells in vitro. PTX significantly improved HPS without altering portal or systemic hemodynamics and downregulated pulmonary ETB receptor levels and eNOS expression and activation. These changes were associated with a reduction in circulating TNF levels and NF-κB activation and complete inhibition of Akt activation. In rat pulmonary microvascular endothelial cells, PTX inhibited shear stress-induced ETB receptor and eNOS expression and eNOS activation. These effects were also associated with inhibition of Akt activation and were reproduced by wortmanin. In contrast, TNF-α had no effects on endothelial ETB and eNOS alterations in vitro. PTX has direct effects in the pulmonary microvasculature, likely mediated through Akt inhibition, that ameliorate experimental HPS.
Relationship Between Human Leucocyte Antigen Class I and Class II and Chronic Idiopathic Urticaria Associated With Aspirin and/or NSAIDs Hypersensitivity
Authors: Pacor Maria Luisa , Di Lorenzo Gabriele , Mansueto Pasquale , Martinelli Nicola , Esposito-Pellitteri Maria , Pradella Paola , Uxa Laura , Di Fede Gaetana , Rini GiovamBattista , Corrocher Roberto
Published: November 2006

Background. HLA genes play a role in the predisposition of several diseases. The aim was to
analyze the prevalence of HLA class I phenotypes and HLA‐DRB1* genotype in patients with CIU associated with ASA and NSAIDs hypersensitivity (AICU). Methods. 69 patients with AICU, and 200 healthy subjects. Results. Subjects with HLA‐B44 and HLA‐Cw5 antigens were more
represented in patients with AICU than in control group. Subjects with HLA‐A11, HLA‐B13, HLACw4,
and HLA‐Cw7 antigen were more represented in control group than in patients with AICU.
Multiple logistic regression demonstrated an association of HLA‐Cw4 and HLA‐Cw7 with a lower
risk of AICU, whereas carriers of HLA‐B44 phenotype had a higher risk of AICU. No differences
were found between patients and controls as regards to HLA‐DRB1* genotype. Conclusions. We
observed an association between some HLA class‐I antigens and AICU. To the best of our
knowledge this is the first description of such association.
Phosphorylation by DNA-Dependent Protein Kinase Is Critical for Apoptosis Induction by Insulin-Like Growth Factor Binding Protein-3
Authors: Cobb Laura J. , Liu Bingrong , Lee Kuk-Wha , Cohen Pinchas
Published: November 2006

Insulin-like growth factor (IGF) binding protein-3 (IGFBP-3) promotes apoptosis of cancer cells by both IGF-dependent and IGF-independent mechanisms. In vitro phosphorylation of IGFBP-3 by DNA-dependent protein kinase (DNA-PK) has been reported but with unknown functional relevance. Using a chemical inhibitor for DNA-PK in prostate cancer cells and a paired system of glioblastoma cell lines that either lack or express DNA-PK, we show that the apoptosis-promoting and growth-inhibitory actions of IGFBP-3 are completely abrogated in the absence of catalytically active DNA-PK. In the absence of DNA-PK activity, IGFBP-3 has reduced nuclear accumulation and is unable to bind its nuclear binding partner retinoid X receptor (RXR) α. We assessed the importance of the three potential DNA-PK phosphorylation sites in IGFBP-3 using PCR-based site-directed mutagenesis. When transfected into 22RV1 cells, IGFBP-3-S165A and IGFBP-3-T170A functioned in an identical manner to wild-type IGFBP-3 to induce apoptosis. In contrast, IGFBP-3-S156A was unable to promote apoptosis and exhibited reduced nuclear accumulation, suggesting a key role for DNA-PK-dependent phosphorylation in the regulation of IGFBP-3 action. These studies reveal a novel regulatory mechanism for the actions of IGFBP-3 in prostate cancer and show phosphorylation of Ser156 to be functionally critical in its apoptosis-inducing actions. (Cancer Res 2006; 66(22): 10878-84)
Oncogenic Serine-Threonine Kinase Receptor-Associated Protein Modulates the Function of Ewing Sarcoma Protein through a Novel Mechanism
Authors: Anumanthan Govindaraj , Halder Sunil K. , Friedman David B. , Datta Pran K.
Published: November 2006

Although much is known about the oncogenic functions of chimeric Ewing sarcoma (EWS) fusion proteins that result from chromosomal translocations, the cellular role of the normal EWS protein is not well characterized. We have previously identified a WD domain–containing protein, serine-threonine kinase receptor-associated protein (STRAP), which inhibits transforming growth factor β (TGF-β) signaling through interaction with receptors and Smad7 and promotes growth and enhances tumorigenicity. Here, we report the interaction between STRAP and EWS using matrix-assisted laser desorption/ionization, time-of-flight and tandem mass spectrometry. Although STRAP is localized in both cytoplasm and nucleus, nuclear STRAP colocalizes and associates specifically with EWS in the nucleus through its NH2 and COOH termini. We have found that normal EWS protein is up-regulated in human cancers, which correlates with the up-regulation of STRAP in 71% of colorectal cancers and 54% of lung cancers, suggesting a cooperative role of these two proteins in human cancers. TGF-β has no effect on STRAP and EWS interaction. However, EWS, like STRAP, attenuates TGF-β-dependent transcription. STRAP inhibits EWS-dependent p300-mediated transactivation of EWS target genes, such as ApoCIII and c-fos, in a TGF-β-independent manner. Interestingly, we have shown that STRAP blocks the interaction between EWS and p300, whereas the complex formation between STRAP and EWS is not affected by p300. These results suggest that STRAP inhibits the transactivation function of EWS by displacing p300 from the functional transcriptional complex. Thus, this study provides a novel TGF-β-independent function of STRAP and describes a mechanism by which STRAP regulates the function of oncogenic EWS protein. (Cancer Res 2006; 66(22): 10824-32)
Comparison of PrASE and Pyrosequencing for SNP Genotyping
Authors: Käller Max , Hultin Emilie , Holmberg Kristina , Persson Marie-Louise , Odeberg Jacob , Lundeberg Joakim , Ahmadian Afshin
Published: November 2006

Background

There is an imperative need for SNP genotyping technologies that are cost-effective per sample with retained high accuracy, throughput and flexibility. We have developed a microarray-based technique and compared it to Pyrosequencing. In the protease-mediated allele-specific extension (PrASE), the protease constrains the elongation reaction and thus prevents incorrect nucleotide incorporation to mismatched 3'-termini primers.

Results

The assay is automated for 48 genotyping reactions in parallel followed by a tag-microarray detection system. A script automatically visualizes the results in cluster diagrams and assigns the genotypes. Ten polymorphic positions suggested as prothrombotic genetic variations were analyzed with Pyrosequencing and PrASE technologies in 442 samples and 99.8 % concordance was achieved. In addition to accuracy, the robustness and reproducibility of the technique has been investigated.

Conclusion

The results of this study strongly indicate that the PrASE technology can offer significant improvements in terms of accuracy and robustness and thereof increased number of typeable SNPs.
Plasma RNA Integrity Analysis
Authors: WONG BLENDA C.K. , DENNIS LO Y.M.
Published: November 2006

Abstract:  The detection of cell‐free RNA in plasma and serum of human subjects has found increasing applications in the field of medical diagnostics. However, many questions regarding the biology of circulating RNA remain to be addressed. One issue concerns the molecular nature of these circulating RNA species. We have recently developed a simple and quantitative method to investigate the integrity of plasma RNA. Our results have suggested that cell‐free RNA in plasma is generally present as fragmented molecules instead of intact transcripts, with a predominance of 5′ fragments. In this article, we summarize the basic principles in the experimental design for plasma RNA integrity analysis and highlight some of the important technical considerations for this type of investigation.
Tsixdefective in splicing is competent to establishXistsilencing
Authors: Sado Takashi , Hoki Yuko , Sasaki Hiroyuki
Published: November 2006

Dosage differences of X-linked genes between male and female mammals are compensated for by a mechanism known as X-inactivation, and the noncoding Xist gene plays a crucial role in this process. The expression of Xist is regulated in cis by its noncoding antisense gene, Tsix, whose transcripts (though a fraction of them stay unspliced),are processed like common proteincoding RNAs. It has been suggested that certain classes of sense-antisense pairs of RNA are causally involved in not only gene regulation but also higher order chromatin structure in various organisms. In fact, recent studies demonstrated that Tsix modulates Xist expression through modification of the chromatin structure. It is still unknown, however, whether the RNA product is important for the function of Tsix or whether the antisense transcription is sufficient. To obtain insight into this issue, we eliminated the splicing products of Tsix in the mouse and explored the effects of this elimination on Tsix-mediated Xist silencing. To our surprise, the Xist locus was stably repressed on the X carrying the splicing-defective Tsix allele. Moreover, the repressive chromatin configuration was properly established at the Xist locus. These unexpected results indicate that the splicing products are dispensable for Tsix-mediated Xist silencing.
Synaptic Integration of Olfactory Information in Mouse Anterior Olfactory Nucleus
Authors: Lei Huimeng , Mooney Richard , Katz Lawrence C.
Published: November 2006

Individual odorants activate only a small fraction of mitral cells in the mouse main olfactory bulb (MOB). Odor mixtures are represented by a combination of activated mitral cells, forming reproducible activation maps in the olfactory bulb. However, how the activation of a cohort of narrowly tuned mitral cells by odor mixtures is read out synaptically by neurons in higher-level olfactory structures, such as the anterior olfactory nucleus (AON), is mostly unknown. In the current study, we used intracellular and extracellular recordings to examine and compare responses of AON neurons and MOB mitral cells to a panel of structurally diverse odorants presented either as mixtures or as individual components. We found that a majority of individual AON neurons could be synaptically activated by several mixtures of structurally dissimilar components and by several dissimilar components in an effective mixture. The suprathreshold response of an AON neuron to an effective mixture often exceeded the sum of its suprathreshold responses to all of the components in that mixture, indicating a nonlinear combinatorial interaction. In contrast to the broad responsiveness of AON neurons, the majority of mitral cells were activated by only one or two components in a single mixture. The broader responsiveness of AON neurons relative to mitral cells suggests that individual AON neurons synaptically integrate several functionally distinct mitral cell inputs.
Suppliers in the privatised UK wastewater market and their possible moves towards integrated solutions
Authors: Windahl Charlotta
Published: November 2006

An increasing number of companies in the capital goods industry are turning towards new strategies where the focus is to add value for customers by providing integrated solutions (combining products and services), instead of selling components, spare parts and support services. These new strategies represent moves in the value chain and create a need for new business models as well as new competencies.

In this paper, the fairly new concept of integrated solutions is explored in the context of a privatised industry. The findings are based on empirical case studies carried out at two companies supplying products and services to the UK wastewater industry. In the UK, both water companies and their suppliers are influenced by economic and environmental regulations, an increased focus on cost, and outsourcing. On one hand, the two manufacturers have increased their competence with respect to system integration and operational services – competencies for supplying integrated solutions. On the other hand, a fragmented and vertically structured market with a multitude of different actors increases the distance between the water companies and the manufacturers. In addition, the division of the industry into a capital and operational side complicates the coordination between new sales and services.
Assessing the economic benefits of improved irrigation management: a case study in Bangladesh
Authors: Dey Nepal C. , Bala Sujit K. , Hayakawa Seiji
Published: November 2006

This paper explains the economic benefits that the country can achieve if improved irrigation management is followed in Bangladesh. The present study has been carried out using data from different studies by different organizations on the existing status of irrigation management practices in Bangladesh. As a result, defects were detected in the system, which are possible to eliminate through taking up various effective measures. A quantitative assessment has been done based on savings to be acquired as a result of eliminations of the defects. An additional amount of US$140 million may be saved from improved irrigation and water management practices, US$543 million from elimination of the present system loss of water and US$155 million by providing supplementary irrigation in the Aman (summer) season. An amount of US$108 million may be saved by enhancing mechanical efficiency of the diesel driven irrigation equipment through proper operation and in time repair and maintenance, US$362 million through proper conservation of water in khal (local drainage channel), beel (small water bodies), haor (comparatively larger water bodies) and pond and US$38 million by controlling unplanned installation of irrigation equipment. The Government of Bangladesh is to spend only an amount of about US$1.74 million for successful implementation of proper irrigation and other management activities, when in total an amount of about US$1,344.26 million may be thus saved and added annually in the economy of Bangladesh. The amount thus saved is about one-fifth of the total Bangladesh Budget for the Fiscal Year of 2002/03 (US$7,570 million) and about one-sixth of the total Bangladesh Budget for the Fiscal Year of 2003/04 (US$8,962 million).
Novel hydrolyzable and biodegradable cationic gemini surfactants: 1,3‐bis[(acyloxyalkyl)‐dimethylammonio]‐2‐hydroxypropane dichloride
Authors: Tatsumi Taiga , Zhang Wanbin , Kida Toshiyuki , Nakatsuji Yohji , Ono Daisuke , Takeda Tokuji , Ikeda Isao
Published: November 2006

Novel cationic gemini surfactants, 1,3‐bis[(acyloxyalkyl)dimethylammonio]‐2‐hydroxypropane dichloride, which possess hydrolyzable oxycarbonyl moieties in the lipophilic portions, were prepared. These surfactants showed much better micelle‐forming ability, ability to lower surface tension, foaming ability, and foam stability than corresponding single‐chain surfactants. Their surface properties were largely influenced by changing the position of the oxycarbonyl group in the lipophilic moiety. The critical micelle concentration decreased with a decreasing number of methylene units in the linking moiety between the ammonio and the oxycarbonyl groups within the comparison of lipophilic chains of the same length. These cationic gemini surfactants also showed good biodegradability.
Phase behavior and detergency study of lauryl alcohol ethoxylates with high ethylene oxide content
Authors: Goel Satish K.
Published: November 2006

Nonionic surfactants such as fatty alcohol ethoxylates have been extensively used in many detergent applications, because of their high calcium ion tolerance, low critical micelle concentrations, and mildness. Although ethoxylates containing high ethylene oxide (EO) content (EO>10 moles) score higher than their low‐FO counterparts on many of these desired properties, they have not been studied adequately in the context of detergency, primarily because their cloud points (CP) are higher than normal wash temperatures, typically >100°C, and thus cannot be measured. However, once the CP are manipulated appropriately using salting‐out electrolytes, these surfactants can offer certain distinct advantages in terms of their molecular and phase structure. We have studied the phase structure and clouding behavior of tetradecyl ethylene‐oxide mono dodecyl alcohol (C12EO14), a broad‐range ethoxylate, as a function of the concentrations of various electrolytes. We found that, beyond a certain critical concentration, the CP decreases monotonically with increasing salt concentration. For sodium salts of various anions, the CP depression is inversely proportional to the lyotropic number of the anion. Similarly, for chloride salts of various cations, CP depression is inversely proporitional to the lyotropic number of the cation However, the effect of changing anion is stronger than that of changing cation. A micrograph of a water penetration scan at room temperature indicates the presence of isotropic L1; hexagonal, isotropic L2; and solid phases with increasing surfactant concentration. As is the case with low‐FO nonionics, a maximum in detergency of model oily soils was found to correlate well with the minimum in oil/water interfacial tension when plotted vs. temperature. Ross Miles foam height increases with increasing concentration of salt.
Kinetics of precipitation of surfactants. I. Anionic surfactants with calcium and with cationic surfactants
Authors: Rodriguez Cheryl H. , Lowery Lori H. , Scamehorn John F. , Harwell Jeffrey H.
Published: November 2006

Isoperibol calorimetry was used to measure the rates of precipitation for aqueous solutions of several anionic surfactants with calcium and of anionic and cationic surfactants. A monomer concentration‐dependent supersaturation ratio was used to describe the relative rates of precipitation for the surfactant systems studied. This supersaturation ratio allows for the relative rates of precipitation of any surfactant solution to be compared whether micelles are present in solution or not. In general, as the supersaturation ratio increases, the rate of precipitation decreases and the induction time decreases, bot above and below the critical micelle concentration (CMC). The rate of precipitation of sodium dodecyl sulfate (SDS) with dodecyl pyridinium chloride is much slower than the rate of precipitation of the anionic surfactants with calcium for similar supersaturation ratios. The rate of precipitation of SDS with calcium is slightly faster than the rate of precipitation of sodium octyl benzene sulfonate for similar supersaturation ratios. Studies of precipitate crystals, conducted using image analysis, showed that size and shape dependent on the initial supersaturation, the precipitating surfactant molecule, and the extent of aging (until an equilibrium size and shape was reached). Also, differences in the appearance of crystals formed from solutions above and below the CMC were observed. These were most likely due to the difference in supersaturation of these solutions. The crystals formed due to precipitation of SDS with calcium at a concentration above the CMC formed flat trapezoidal, rhombic and hexagonal shapes. These aged into clusters by 1 wk. For a solution that was precipitated at concentrations beginning below the CMC, the crystals began as elongated and rhombic flat plates and aged into trapezoidal, rhombic, and needle‐like structures.
Kinetics of precipitation of surfactants. II. Anionic surfactant mixtures
Authors: Rodriguez Cheryl H. , Scamehorn John F.
Published: November 2006

Precipitation kinetics were measured for calcium‐induced precipitation of mixtures of two anionic surfactants. The overall time required for precipitation to occur increased dramatically in specific ranges of compositions for the surfactant mixtures when compared to single components. Adsorption of the nonprecipitating surfactant onto the precipitate surface was shown to be responsible for this remarkable synergism. The higher the supersaturation of surfactant monomers, the more rapidly precipitation occurred. Under conditions where both surfactants were supersaturated, precipitation sometimes occurred in stepwise fashion, where crystals of different composition were formed with different induction times. Image analysis of the crystalline precipitate showed that crystal habit was affected when the two surfactants were mixed, indicating that processes such as adsorption and coprecipitation (most likely by inclusion) were occurring. When the crystals were allowed to age in solution for a period of 1 wk, the crystalline phase from the mixed surfactant solutions was found to separate into two types of crystals, which resembled week‐old crystals formed from single surfactant systems.
Synthesis and application of polymeric fluorescent whitening agents
Authors: Liu Yun , Guo Guangxun , Zhang Jun , Sun Yu E
Published: November 2006

From p‐toluic acid, a series of polymeric fluorescent whitening agents (FWA) was synthesized. In the paper are given the details for the synthesis of the FWA and their intermediates. The products are water‐dispersible or water‐soluble, have good affinity with hydrophobic fabrics, affect the soil‐releasing effect on polyester, soiled or aged cotton fabrics, and can be incorporated into concentrated fabric conditioner, a product type using FWA that is being developed. Polymeric FWA add excellent brightness to polyester and soiled or aged cotton for which the usual anionic FWA have little effect.
Effects of various nutritional supplements on biosurfactant production by a strain of Bacillus subtilis at 45°C
Authors: Makkar R. S. , Cameotra S. S.
Published: November 2006

Effects of various factors on growth and biosurfactant production by Bacillus subtilis MTCC 2423 were studied. Sucrose (2%) and potassium nitrate (0.3%) were the best carbon and nitrogen sources. The addition of various metal supplements (magnesium, calcium, iron, and trace elements) greatly affected growth and biosurfactant production. The effect of the metal cations, used together, is greater than when they are used individually. The biosurfactant production increased considerably (almost double) by addition of metal supplements. Very high concentrations of metal supplements, however, inhibited biosurfactant production. Amino acids such as aspartic acid, asparagine, glutamic acid, valine, and lysine increased the final yield of biosurfactant by about 60%. The organism could produce biosurfactant at 45°C and within the pH range of 4.5–10.5. The biosurfactant was thermostable and pH stable (from 4.0 to 12.0). The capability of the organism to produce biosurfactant under thermophilic, alkaliphilic, and halophilic conditions makes it a suitable candidate for field applications. Infrared, nuclear magnetic resonance, and mass spectroscopy studies showed the surfactant to be identical to surfactin.
Study of alcohol‐free microemulsion systems containing fatty acids as cosurfactants
Authors: Lohateeraparp Prapas , Wilairuengsuwan Pongtai , Saiwan Chintana , Sabatini David A. , Harwell Jeffrey H.
Published: November 2006

In this study, fatty acids with carbon chains ranging in length from 3 to 8 (propyl to octyl) were used in place of alcohols to form microemulsion systems. The microemulsion systems contained sodium dodecyl sulfate (SDS), hexane, fatty acid, water, and NaCl. The phase behavior of these systems was examined using salinity scans at 25°C. The results showed that propanoic and butanoic acids promoted the formation of clear isotropic microemulsions, whereas the other fatty acids promoted a gel formation. High hexane solubilization was obtained with all of the systems. The optimum solubilization parameter (SP*) and optimum salinity (S*) decreased with increasing SDS concentration. With increasing fatty acid chain length, S* decreased but SP* increased. Conductivity meausrements showed that, during the salinity scan, the conductivity of the systems was relatively unchanged, gradually decreased, or was a maximum at a given value. Interfacial tension (IFT) measurements showed that ultralow IFT were realized between microemulsion and oil phases using the fatty acids and that SP* and IFT were inversely related. The results of this study confirm that microemulsions can be formulated without alcohols through replacement of the alcohols with the appropriate fatty acids.
Surface and thermodynamic properties of diquaternary bola‐form amphiphiles containing an aromatic spacer
Authors: Negm Nabel A. , Mohamed Ammona S.
Published: November 2006

A series of diquaternary ammonium bromides having phenyl groups with different (CH2/N+) ratios were synthesized. The critical micelle concentration of each amphiphile was determined using equilibrium surface tension and equivalent conductance data. Air/water interfacial parameters were measured at 20, 35, and 50°C. The surface tension isotherms of the different diquaternary amphiphiles showed two region of discontinuity corresponding to two critical micelle concentrations. The first was related to the spherical nature of the micelles, whereas the second was related to the multiple loops of the lamellar aggregates. The prepared compounds were evaluated as a new class of diquaternary ammonium compounds for future application in protection of steel fabrics against aggressive media (2 N HCl). The results showed that the prepared amphiphiles offered good corrosion inhibition efficiency. Also, increasing the hydrophobic chain length and/or concentration increased their efficiency.
Surface properties of surfactants derived from natural products. Part 1: Syntheses and structure/property relationships—Solubility and emulsification
Authors: Piispanen Peter S. , Persson Marcus , Claesson Per , Norin Torbjörn
Published: November 2006

Several novel and some previously known, mostly sugar‐based, surfactants have been synthesized and some of their surface properties have been characterized and compared with those of commercial nonylphenol ethoxylates. The surfactant solubility in water, ethanol, and dodecane was studied. The properties of these compounds as emulsification agents in systems composed of the surfactant with water/isopropyl myristate, water/rapeseed oil, and water/dodecane are presented. The aqueous solubility of the surfactants follows the general trend expected from their hydrophilic‐lipophilic balance according to Griffin (HLBG), but it is also clear that the nature of the headgroup and the structure of the nonpolar part affect the solubility in a manner not aptured in the standard HLBG concept. An ester or amine group as the connecting unit between the hydrophile and the hydrophobe produces a more water‐soluble surfactant than the corresponding amide derivative. Some effective emulsifiers were found. For instance, the surfactants with a dehydroabietic nonpolar group appear to be promosing emulsifiers. Most sugar‐based surfactants were able to form macroemulsions of up to around 2 wt/vol% of oil. The stability of many of these amulsions was very high, extending for months.
Glucamine‐based gemini surfactants I: Gemini surfactants from long‐chainN‐alkyl glucamines and α,ω‐diepoxides
Authors: Warwel S. , Brüse F. , Schier H.
Published: November 2006

N‐Alkyl glucamines can be reacted with α,ω‐diepoxides to yield gemini (dimeric) surfactants similarly to the reaction of glucamine with terminal epoxides. Under the conditions chosen for this work, epoxides were quantitatively converted in the presence of an equimolar amount of amine to gemini surfactants. Reactions could be carried out under mild conditions (70°C) in methanol, and products were obtained quantitatively by removing the solvent. The combination ofN‐octyl glucamine,N‐decyl glucamine, orN‐dodecyl glucamine with diepoxides of α,ω‐diolefins having chain lengths of C8, C9, C10, or C14resulted in gemini surfactants differing in spacer length and length of hydrophobic alkyl chains. Surface‐active properties were studied by measuring surface tension and evaluating foaming properties. Tensiometric studies showed the reduction of surface tension down to 29–33 mN/m and critical micelle concentrations often in the range of 3–150 mg/L. Comparison of a selected gemini surfactant [1,8‐bis(N‐dodecyl glucamino‐2,7‐octane diol] with its corresponding “single surfactant” demonstrated the enhancement of surface‐active properties afforded by the gemini structure.
Surfactant properties of low molecular weight phospholipids
Authors: Weschayanwiwat Punjaporn , Scamehorn John F. , Reilly Peter J.
Published: November 2006

Surface tensions, critical micelle concentrations (CMCs), contact angles on hydrophobic polyethylene, and foaming characteristics of phosphatidic acids, phosphatidylcholines, phosphatidylethanolamines, and phosphatidylglycerols were measured to determine their suitability as substitutes for traditional surfactants. These phospholipids have fatty acid chains of 5 to 12 carbon atoms, a range over which they are soluble at room temperature. Their surface tensions decrease with increasing concentrations until their CMCs are reached, above which their plateau surface tensions are as low as 21 mN/m, indicating excellent surface activities. In general, plateau surface tensions decrease with increasing chain length within each phospholipid type. The classical relationship for In CMC vs. chain length is followed with slopes typical of anionic surfactants for phosphatidic acids and phosphatidylglycerols and resembling zwitterionic surfactants for phosphatidylcholines and phosphatidylethanolamines, consistent with the charge on the hydrophilic group. The wetting capabilities of aqueous solutions on polyethylene are good and foam heights and stabilities are high, the latter two properties being comparable to traditional anionic (sodium dodecylsulfate) and nonionic (octylphenol polyethoxylate) surfactants. Some anomalies are observed regarding the effect of chain length on wetting and foaming, probably due to the depletion effect. Many phospholipids slowly degrade in aqueous solution. We conclude that short‐chain phospholipids exhibit excellent surfactant properties and may be useful in many applications.
Synthesis and properties of new cationic surfactants: 1‐Alkylthiomethyl‐3‐carbamoylpyridinium chlorides
Authors: Pernak Juliusz , Zygadło Małgorzata , Cieniecka‐Rosłonkiewicz Anna
Published: November 2006

1‐Alkylthiomethyl‐3‐carbamoylpyridinium and 1‐alkylthiomethyl‐4‐carbamoylpyridinium chlorides were prepared by the reaction of nicotinamide or isonicotinamide with chloromethyl alkyl sulfides. The obtained chlorides were examined for their antimicrobial activities. 4‐Carbamoyl‐1‐dodecylthiomethylpyridinium chloride exhibited strong antimicrobial activity, similar to the activity of benzalkonium chloride. All synthesized chlorides underwent hydrolysis in aqueous solutions at temperatures higher than 70–75°C. In aqueous solution 1‐alkylthiomethyl‐3‐carbamoylpyridinium chlorides reacted with ozone. A new generation of cationic surfactants that were hydrolyzed and ozone‐reactive in an aqueous solution was synthesized during this study.
Role of partitioning site in producing viscoelasticity in micellar solutions
Authors: Kumar Sanjeev , Sharma Damyanti , Kabir‐ud‐Din
Published: November 2006

The effect of the addition of four aromatic compounds (anthranilic acid, benzoic acid, sodium anthranilate, and sodium benzoate) to 10 mM cetyltrimethylammonium bromide solutions is investigated by 1H nuclear magnetic resonance spectroscopy. The site of solubilization of these molecules inside the micelle is inferred. It is shown that sodium anthranilate, which partitions near the head group region together with the external part of the micellar palisade layer (in Rosen's terminology), is most effective in producing micellar growth (or viscoelasticity). In this context a deeper penetration of an additive inside the micelle disqualifies it to produce viscoelasticity in the system. Furthermore, interior or palisade region solubilization depends on the nature of groups attached to the main benzene ring.
Determination of average molecular weight of commercial surfactants: Alkylpolyglucosides and fatty alcohol ethoxylates
Authors: Bravo Rodriguez V. , Jurado Alameda E. , Reyes Requena A. , García López A. I. , Bailón‐Moreno R. , Cuevas Aranda M.
Published: November 2006

A quick and simple method, based on elemental and moisture analyses, is proposed for estimating the mean molecular weight of alkylpolyglucosides and fatty alcohol ethoxylates, which are nonionic surfactants that are attracting growing interest for their ease of biodegradation. Analyses for the water content and the elemental composition were carried out for three alkylpolyglucosides (Henkel‐Cognis): Glucopon 215, Glucopon 600, and Glucopon 650, as well as for five fattyalcohol ethoxylates (Kao Corporation): FINDET 10/15, FINDET 10/18, FINDEt 1214N/16, FINDET 1214N/23, and FINDET 1618/A18. Application of the method requires knowing the mean number of carbons in the fatty acid chains of the surfactant. This number, in the case of the alkylpolyglucosides assayed here, has been determined experimentally by high‐performance liquid chromatography.
Mechanism of the enhanced spreading of some mixtures of anionic and cationic hydrocarbon chain surfactants on a highly hydrophobic polyethylene surface
Authors: Rosen Miltion J.
Published: November 2006

The objective of this investigation was to measure the interfacial properties and interactions among mixtures of different cationic and anionic surfactants at the hydrophobic solid/aqueous solution interface to explain the different spreading factors or behavior of the mixed surfactants on a highly hydrophobic polyethylene (PE) film. A synergistic effect in the spreading of the mixed surfactant solutions on the PE film was observed when the surfactants were added sequentially. Other interfacial phenomena related to this surfactant spreading, such as interaction parameters at the solid/liquid (S/L) and liquid/air (L/A) interfaces in the mixtures adsorbed at various interfaces and dynamic contact angles of the mixed surfactant solutions during the process of spreading on the PE substrate, were investigated to obtain insight into this enhanced spreading. All the interaction parameters were more negative than −20, indicating very strong interaction between these cationic and anionic surfactants. The interaction parameters at the S/L interface were more negative than at the L/A interface, showing that the attractive interaction at the S/L interface was stronger than at the L/A interface. The spreading was related to the difference in the interaction parameters at the S/L and L/A interfaces and to the dynamic contact angle.
Phase behavior of a fragrance compound system: Water/phenethyl alcohol/laureth 4/glycerol
Authors: Friberg Stig E. , Al‐Bawab Abeer , Sandburg Joel D. , Barber Jennifer L. , Yin Qi , Aikens Patricia A.
Published: November 2006

The phase diagram of the system water/phenethyl alcohol (PEA)/Laureth 4 (L4)/glycerol was determined using visual observation, optical microscopy, small‐angle X‐ray diffractometry, and the vapor pressure of phenethyl alcohol measured by gas chromatographic analysis of headspace vapor at equilibrium. The phase diagram was shown to be dominated by three narrow isotropic liquid solubility regions along the water/glycerol, glycerol/PEA, and PEA/L4 axes. Vapor pressure measurements and tie‐line determinations showed the final state of formulations after evaporation of water to be emulsions of glycerol/PEA‐in‐L4/PEA or L4/PEA‐in‐glycerol/PEA. PEA was predominantly dissolved in the L4/PEA phase because the chemical potential of PEA in glycerol was high, even at modest concentrations.
Soil release polymers
Authors: O'Lenick Anthony J.
Published: November 2006

Cleaning today's fabrics requires a sophisticated formulated product that is (i) consumer friendly, (ii) environmentally friendly, (iii) effective with a broad range of fabrics, (iv) effective at accepted wash temperatures, (v) effective with a variety of washing machines, and (vi) cost effective. Today “cleaning” includes not only removal of soils but also provision to the consumer of an appropriate hand and improved fabric cleanability in subsequent washings. It is therefore not surprising that the complexity of today's detergents has increased significantly over the last generation. Antiredeposition agents and soil release polymers have become important additives to today's laundry products.
Method to produce 9(S)‐hydroperoxides of linoleic and linolenic acids by maize lipoxygenase
Authors: Gardner Harold W. , Grove Marilyn J.
Published: November 2006

Seed from maize (corn) Zea mays provides a ready source of 9‐lipoxygenase that oxidizes linoleic acid and linolenic acid into 9(S)‐hydroperoxy‐10(F), 12(Z)‐octadecadienoic acid and 9(S)‐hydroperoxy‐10(E), 12(Z), 15(Z)‐octadecatrienoic acid, respectively. Corn seed has a very active hydro‐peroxide‐decomposing enzyme, allene oxide synthase (AOS), which must be removed prior to oxidizing the fatty acid. A simple pH 4.5 treatment followed by centrifugation removes most of the AOS activity. Subsequent purification by ammonium sulfate fractional precipitation results in negligible improvement in 9‐hydroperoxide formation. This facile alternative method of preparing 9‐hydroperoxides has advantages over other commonly used plant lipoxygenases.
Inhibition of purified pig and human liver retinyl ester hydrolase by pharmacologic agents
Authors: Schindler Rainer
Published: November 2006

Identification of inhibitors of retinyl ester hydrolase (RFH) would help to elucidate its role in vitamin A metabolismin vivo. By using standard incubation conditions, the effects of 215 drugs as potential inhibitors of purified pig and human liver REH when acting on micellar substrate retinyl palmitate were evaluated at 16.7, 167, and 1670 μM. Out of the compounds tested, 103 were inhibitors of the pig liver enzyme. The most potent compounds, in order of decreasing activity, were chloral hydrate, lovastatin, phytomenadione, alimemazine, physostigmine, thioridazine, phenoxybenzamine, probucol, cinnarizine, cyclandelate, amiodarone, flupenthixol, and naftidrofuryl; this order is roughly similar to that of their inhibition of human liver REH. Of the 10 tricyclic ring‐containing drugs tested, alimemazine was the most potent enzyme inhibitor. The concentrations necessary for 50% enzyme inhibition ranged from <2.6 up to >540 μM. Moreover, inhibitory kinetic studies showed that at least two pharmaceutica's, chloral hydrate and amiodarone, are potent REH inhibitors at therapeutically achievable serum concentrations. First‐pass metabolites were inactive as REH inhibitors compared to that of the parent compounds, in the cases of chloral hydrate, lovastatin, and cyclandelate.
Necrosis and apoptosis in lymphoma cell lines exposed to eicosapentaenoic acid and antioxidants
Authors: Heimli Hilde , Finstad Hanne S. , Drevon Christian A.
Published: November 2006

The present study is focused on the role of oxidative stress in the induction of either necrosis or apoptosis by eicosapentaenoic acid (EPA) in the lymphoma cell lines Raji and Ramos, respectively. To investigate the different death modes induced by EPA, we assessed the importance of some antioxidants and reactive oxygen species in the two cell lines. We observed that different antioxidants counteracted the necrotic effect of EPA on Raji cells to a different extent, and that vitamin E counteracted EPA‐induced accumulation of superoxide anion in this cell line. On the contrary, no effects of antioxidants were observed on development of apoptosis induced by EPA in Ramos cells, and vitamin E did not counteract EPA‐induced accumulation of superoxide anions in Ramos cells. Moreover, apoptosis was partly inhibited by transcription inhibitors (actinomycin D) and protein synthesis inhibitors (cycloheximide), suggesting dependency upon new protein synthesis prior to apoptosis. Kinase inhibitors (staurosporin and calphostin C) did not alter the EPA‐induced apoptosis. The observed cellular accumulation of superoxide anion following EPA incubation may be important for induction of necrosis in Raji cells. In contrast, none of the other investigated parameters indicated a role of oxidative stress promoted by EPA in the induction of apoptosis in Ramos cells.
Effect of 4‐hydroxy‐2(E)‐nonenal on soybean lipoxygenase‐1
Authors: Gardner Harold W. , Deighton Nigel
Published: November 2006

The oxidation of linoleic acid by soybean lipoxygenase‐1 (LOX‐1) was inhibited in a time‐dependent manner by 4‐hydroxy‐2‐(E)‐nonenal (HNE). Kinetic analysis indicated the effect was due to slow‐binding inhibition conforming to an affinity labeling mechanism‐based inhibition. After 25 min of preincubation of LOX‐1 with and without HNE, Lineweaver‐Burk reciprocal plots indicated mixed noncompetitive/competitive inhibition. Low concentrations of HNE influenced the electron paramagnetic resonance (EPR) signal of 13(S)‐hydroperoxy‐9(Z), 11(E)‐octadecadienoic acid (13‐HPODE)‐generated Fe3+‐LOX‐1 slightly, but higher concentrations completely eliminated the EPR signal indicating an active site hindered from access by 13‐HPODE. HNE may compete for the active site of LOX‐1 because its precursor, 4‐hydroperoxy‐(2E)‐nonenal, is a product of LOX‐1 oxidation of (3Z)‐nonenal. Also, it was an attractive hypothesis to suggest that HNE may disrupt the active site by forming a Michael adduct with one or more of the three histidines that ligate the iron active site of LOX‐1.
Transformations of DHEA and its metabolites by rat liver
Authors: Lardy Henry , Marwah Ashok , Marwah Padma
Published: November 2006

Because dehydroepiandrosterone (DHEA) has a wide variety of weak beneficial effects in experimental animals and humans, we searched for metabolites of this steroid in the hope of finding more active compounds that might qualify for the title “steroid hormone”. Incubation of DHEA with rat liver homogenate fortified with energy‐yielding substrates resulted in rapid hydroxylation at the 7α‐position of the molecule and subsequent conversion to other 7‐oxygenated steroids in the sequence DHEA»7α‐hydroxyDHEA»7‐oxoDHEA»7β‐hydroxyDHFA, with branching to diols, triols, and sulfate esters. The ability of these metabolites to induce the formation of liver thermogenic enzyme activity increased from left to right in that sequence. A total of 25 different steroids were characterized, and at least six additional structures that are currently under study were produced from DHEA. 7‐OxoDHEA is more effective than DHEA in enhancing memory performance in old mice and in reversing the amnesic effects of scopolamine.
Hepatic Δ9, Δ6, and Δ5 desaturations in non‐insulin‐dependent diabetes mellitus eSS rats
Authors: Montanaro Mauro A. , Rimoldi Omar J. , Igal R. Ariel , Montenegro Silvana , Tarres María C. , Martínez Stella M. , Brenner Rodolfo R.
Published: November 2006

Both diabetes mellitus type 1 and diabetes mellitus type 2 are widespread diseases that alter carbohydrate and lipid metabolism. e Stilmann‐Salgado (eSS) rats are experimental animals that spontaneously evolve to a state similar to that of young people affected by non‐insulin‐dependent diabetes mellitus (NIDDM; type 2). Using 6‐mon‐old eSS rats that, according to the literature [Martinez, S.M., Tarrés, M.C., Montenegro, S, Milo, R., Picena, J.C., Figueroa, N., and Rabasa, S.R. (1988) Spontaneous Diabetes in eSS Rats, Acta Diabetol. Lat. 25, 303–313], had already developed insulin resistance, we investigated the changes evoked on Δ9, Δ6, and Δ5 liver desaturases. The abundance of mRNA and enzymatic activities were measured, as well as the FA composition of liver microsomal lipids. Compared to control rats, the mRNA content and activity of SCD‐1 (stearoyl CoA‐desaturase, isoform of the Δ9 desaturase) were significantly higher, urase, isoform of the Δ9 desaturase) were significantly higher, whereas the mRNA and activities of Δ6 and Δ5 desaturases were not significantly modified. Correspondingly, the proportion of 18∶1n−9 and the ratios of 18∶1n−9/18∶0 and 16∶1/16∶0 in lipids were significantly increased, whereas the proportion of 20∶4n−6 was unaltered. These effects were found while glycemia was constant or increased. The results are completely opposite those described in insulin‐dependent diabetes mellitus (type 1), in which a depression of all the desaturases is found. They suggest that in eSS rats, the activities of the desaturases were not modified by an insulin‐resistance effect. Moreover, we suggest that the enhancement of SCD‐1 activity might be considered as another typical sign of the NIDDM syndrome, because it has also been found in other animal models of NIDDM, for example, the ones evoked by the sucrose‐rich diet and in the Zucker rat.