bluuebunny/crossref_metadata_2025 huggingface dataset:
Lymphovascular invasion as a tool to further subclassify T1b esophageal adenocarcinoma
Authors: Cen Putao , Hofstetter Wayne L. , Correa Arlene M. , Wu Tsung‐Teh , Lee Jeffery H. , Ross William A. , Davilla Marta , Swisher Stephen G. , Fukami Norio , Rashid Asif , Maru Dipen , Ajani Jaffer A.
Published: January 2008

BACKGROUND.

Lymphovascular invasion (LVI) and/or lymph node metastases (LNM) adversely influence the overall survival (OS) of patients with T1 esophageal adenocarcinoma. Although endoscopic therapy may be adequate for patients with T1a cancer, patients with T1b cancer require esophagectomy/lymphadenectomy. The authors hypothesized that LVI status would subclassify T1b cancers and facilitate new therapeutic strategies.

METHODS.

Ninety‐nine consecutive patients with T1 adenocarcinoma were analyzed after they underwent esophagectomy/lymphadenectomy. LNM was assessed in all patients, and LVI was assessed in 89 patients. OS was correlated with pathologic cancer stage in association with LVI and LNM.

RESULTS.

The 5‐year OS rate for patients with T1a tumors (88%) was superior to that for patients with T1b tumors (62%; P = .001). The 5‐year OS rate for patients who had cancers without LVI (85%) was superior to the rate for patients who had cancers with LVI (36%; P = .0001). It is noteworthy that, for cancers without LVI, the 5‐year OS rate for patients with T1b tumors (77%) was similar to the rate for patients with T1a tumors (90%; P = .08), but it was superior to the rate for patients with T1b tumors that had LVI (27%; P = .006). The presence of LVI and/or LNM resulted in worse 5‐year OS (≤37%) compared with the lack of LVI and/or LNM (88%; P < .001). The rate of LNM for patients who had T1b tumors without LVI still was 19%, and the relapse rate was 16%.

CONCLUSIONS.

The current results demonstrated that LVI distinguishes the biologic behavior of early esophageal cancer, and patients who have T1b cancer without LVI have a clinical biology similar to that of patients with T1a cancer. If LNM before surgery can be diagnosed with high sensitivity by better endoscopic techniques and/or molecular biomarkers, then a new therapeutic paradigm for T1b cancers could emerge. Further research is needed on patients with T1b esophageal adenocarcinoma. Cancer 2008. © 2008 American Cancer Society.
JC virus T‐antigen expression in sporadic adenomatous polyps of the colon
Authors: Jung Woon‐Tae , Li Mei‐Shu , Goel Ajay , Boland C. Richard
Published: January 2008

BACKGROUND.

JC virus (JCV) has been implicated in the pathogenesis of colorectal cancer; however, its role in premalignant lesions is unknown. The hypothesis that JCV DNA sequences and T‐antigen (T‐Ag) expression may be present in adenomatous polyps of the colon was tested. Furthermore, an association between JCV and microsatellite instability (MSI) was also sought in these lesions.

METHODS.

DNA was extracted from 74 paraffin‐embedded adenomatous polyps. JCV gene sequences were amplified by polymerase chain reaction (PCR), and the specificity confirmed by DNA sequencing. Immunohistochemical staining was performed to localize T‐Ag expression in the adenomas using a monoclonal antibody. For microsatellite instability analysis, 5 mononucleotide repeat markers (BAT‐25, BAT‐26, NR‐21, NR‐24, and NR‐27) were coamplified in a pentaplex PCR and analyzed for deletion mutations.

RESULTS.

JCV T‐Ag sequences were found in 82% (61 of 74) of adenomas, and T‐Ag protein was expressed in 16% (12 of 74) of these polyps. The T‐Ag staining was localized exclusively in the nuclei of adenoma cells, but never in the cytoplasm or the adjacent nonneoplastic cells. The prevalence of MSI‐H and non‐MSI‐H (MSI‐L/MSS) in adenomatous polyps was 9.5% (7 of 74) and 90.5% (67 of 74), respectively. Among the 61 adenomas that harbored JCV sequences, 8% (5 of 61) were MSI‐H, and similarly among 12 adenomatous polyps expressing T‐Ag protein 8% (1 of 12) of the adenomatous polyps were MSI‐H.

CONCLUSIONS.

JCV T‐Ag DNA sequences are frequently present in adenomatous polyps of the colon, and T‐Ag is expressed specifically in the nuclei of these premalignant lesions. This study indicates that JCV T‐Ag is present in the early stage of colonic carcinogenesis. Future studies will be required to determine the molecular mechanism of carcinogenesis in these JCV‐infected lesions. Cancer 2008. © 2008 American Cancer Society.
Fixation of CO2 by Electrocatalytic Reduction and Electropolymerization in Ionic Liquid–H2O Solution
Authors: Chu Daobao , Qin Guoxu , Yuan Ximei , Xu Mai , Zheng Peng , Lu Jia
Published: January 2008

The electrocatalytic synthesis of low‐density polyethylene (LDPE) from carbon dioxide on a nanostructured (ns)TiO2 film electrode was investigated by controlled potential electrolysis in a solvent mixture of water and the ionic liquid 1‐ethyl‐3‐methylimidazolium tetrafluoroborate ([EMI]BF4) at room temperature under ambient pressure. Under these conditions, the nsTiO2 film is remarkably efficient and selective for the electroreduction of CO2. The current efficiency for the formation of the electrolytic product is about 8–14 % at −1.50 V (vs SCE). The electrocatalytic activity of the electrode in the electrochemical reduction of CO2 was investigated by cyclic voltammetry (CV), and the probable electrode reaction mechanism is discussed.
Control of nonlinear phenomena in DC–DC converters: Fuzzy logic approach
Authors: Guesmi Kamel , Hamzaoui Abdelaziz , Zaytoon Janan
Published: January 2008

DC–DC power converters are characterized by cyclic switching of circuit configurations, which gives rise to a variety of nonlinear behaviours. Their occurrence in DC–DC power converters makes the system analysis, control and behaviour prediction difficult. An enhanced modelling method allowing one to obtain an accurate description of the converter behaviour is presented in this paper. A fuzzy control scheme is proposed, and a fuzzy logic controller is then developed to both suppress converter nonlinear phenomena and ensure the averaged input current regulation for a wide range of parameters' variation. Copyright © 2008 John Wiley & Sons, Ltd.
An efficient algorithm for finding all DC solutions of piecewise‐linear circuits
Authors: Yamamura Kiyotaka , Machida Akinori
Published: January 2008

An efficient algorithm is proposed for finding all DC solutions of transistor circuits where characteristics of transistors are represented by piecewise‐linear (PWL) convex monotone functions. This algorithm is based on a simple test (termed the linear programming, LP, test) for non‐existence of a solution to a system of PWL equations in a given region. In the conventional LP test, the system of PWL equations is transformed into an LP problem by surrounding component PWL functions by rectangles. Then the dual simplex method is applied, by which the number of pivotings per region becomes very small. In this letter, we propose a new LP test using the dual simplex method and triangles. The proposed test is not only efficient but also more powerful than the conventional test using the simplex method or rectangles. Copyright © 2008 John Wiley & Sons, Ltd.
Heteroduplex analysis using flow cytometric microbead assays to detect deletions, insertions, and single‐strand lesions
Authors: Hegedüs Éva , Imre László , Pataki Judit , Lizanecz Erzsébet , Székvölgyi Lóránt , Fazakas Ferenc , Bacsó Zsolt , Tóth Attila , Szabó Miklós , Seres Zoltán , Szabó Gábor
Published: January 2008

We explore the possibilities offered by flow cytometric microbead analysis to develop high throughput methods for the detection of deletions/insertions and single‐strand DNA lesions. The products of PCR reactions derived from reference and test samples are denatured and reannealed, then exposed to enzymatic or chemical treatments distinguishing homoduplices from heteroduplices. The biotin‐ and dye labeled reaction products are immobilized on microbeads and the homo‐ and heteroduplices are assessed in separate fluorescence channels, by flow cytometry. Using a model system based on the mixed lineage leukemia gene breakpoint cluster region, we demonstrate that deletions and insertions in genomic DNA can be detected, using S1 nuclease and chemical cleavage to distinguish hetero‐ from homoduplices, or a restriction enzyme cleaving only the homoduplices. Single‐strand discontinuities can also be detected, by combining nick‐translation, using labeled nucleotide, and flow cytometric microbead analysis. The methodical approaches demonstrated are applicable in a versatile manner in basic cell and molecular biological research and also promise direct application for high throughput screening of genetic diseases and lesions, including insertions or deletions of short sequence elements and single‐strand lesions formed at hypersensitive sites in response to apoptotic stimuli. © 2008 International Society for Analytical Cytology
Myelodysplasia and anemia of chronic disease in human tumor necrosis factor‐α transgenic mice
Authors: Capocasale Renold J. , Makropoulos Dorie A. , Achuthanandam Ram , Stowell Nicole , Quinn John , Rafferty Patricia A. , O'Brien Joanne , Emmell Eva , Bugelski Peter J.
Published: January 2008

TNF‐α is a pleitropic cytokine that expresses both pro‐ and anti‐inflammatory activity and transgenic mice expressing human tumor necrosis factor‐α (TNF‐α) exhibit a progressive polyarthritis that models rheumatoid arthritis (RA). One of the common comorbidities of RA is anemia of chronic disease (ACD). The purpose of these experiments was to study the changes in the bone marrow and peripheral blood that accompany polyarthritis in TNF‐α transgenic mice in an effort to better understand the pathogenesis of myelodysplasia and ACD. Polychromatic cytometry, hematology and serum cytokine analysis were used to study the pathogenesis of ACD in human TNF‐α transgenic mice. Our hematological evaluation revealed a mild, compensated, microcytic hypochromic anemia, and monocytosis. In the bone marrow, we observed alterations in cell kinetics, decreased relative expression of transferrin receptor and increased apoptosis and cell death in several late precursor cell populations. Although significant levels of human TNF‐α were found in the serum, neither change in serum murine erythropoietin nor any significant difference observed in serum levels of murine IL‐β, IL‐5, IL‐6, IL‐10, IL‐12(p70), IL‐17, TNF‐α, IFNγ, GM‐CSF, MIP‐1αJE, MCP‐5 was observed. Tg197 mice develop a compensated, microcytic, hypochromic anemia, and a functional iron deficiency by 9 weeks of age. Changes in peripheral blood are reflected in alterations in cell kinetics, transferrin receptor expression and markedly increased apoptosis and cell death in the bone marrow indicating that TNF‐α may contribute to myelodysplasia in ACD. Moreover, since human TNF‐α can interact only with murine TNFR1, our data suggest that TNFR1 may play an important role in the development of ACD © 2008 International Society for Analytical Cytology
Quantification of green fluorescent protein by in vivo imaging, PCR, and flow cytometry: Comparison of transgenic strains and relevance for fetal cell microchimerism
Authors: Fujiki Yutaka , Tao Kai , Bianchi Diana W. , Giel‐Moloney Maryann , Leiter Andrew B. , Johnson Kirby L.
Published: January 2008

Animal models are increasingly being used for the assessment of fetal cell microchimerism in maternal tissue. We wished to determine the optimal transgenic mouse strain and analytic technique to facilitate the detection of rare transgenic microchimeric fetal cells amongst a large number of maternal wild‐type cells. We evaluated two strains of mice transgenic for the enhanced green fluorescent protein (EGFP): a commercially available, commonly used strain (C57BL/6‐Tg(ACTB‐EGFP)10sb/J) (CAG) and a newly created strain (ROSA26‐EGFP) using three different techniques: in vivo and ex vivo fluorescent imaging (for whole body and dissected organs, respectively), PCR amplification of gfp, and flow cytometry (FCM). By fluorescent imaging, organs from CAG mice were 10‐fold brighter than organs from ROSA26‐EGFP mice (P < 0.0001). By PCR, more transgene from CAG mice was detected compared to ROSA26‐EGFP mice (P = 0.04). By FCM, ROSA26‐EGFP cell fluorescence was more uniform than CAG cells. A greater proportion of cells from ROSA26‐EGFP organs were positive for EGFP than cells from CAG organs, but CAG mice had a greater proportion of cells with the brightest fluorescent intensity. Each transgenic strain possesses characteristics that make it useful under specific experimental circumstances. The CAG mouse model is preferable when experiments require brighter cells, whereas ROSA26‐EGFP is more appropriate when uniform or ubiquitous expression is more important than brightness. Investigators must carefully select the transgenic strain most suited to the experimental design to obtain the most consistent and reproducible data. In vivo imaging allows for phenotypic evaluation of whole animals and intact organs; however, we did not evaluate its utility for the detection of rare, fetal microchimeric cells in the maternal organs. Finally, while PCR amplification of a paternally inherited transgene does allow for the quantitative determination of rare microchimeric cells, FCM allows for both quantitative and qualitative evaluations of fetal cells at very high sensitivity in a plethora of maternal organs. © 2008 International Society for Analytical Cytology
Oxidation of intracellular and extracellular fatty acids in skeletal muscle
Authors: Guo ZengKui , Jensen Michael D. , Xu Jinze , Zhou Lianzhen , Persson Xuan‐Mai T. , Balagopal Prabhakaran , Yarasheski Kevin
Published: January 2008

Fatty acids are a major fuel for many tissues, and abnormal utilization is implicated in diseases. However, tissue fatty acid oxidation has not been determined reliably in vivo. Furthermore, fatty acid oxidation has not been partitioned into intracellular and extracellular components. In this report, a one‐pool model is described that enables direct quantitation of fluxes of intracellular and plasma fatty acids to mitochondria in skeletal muscle using dual stable isotopes and liquid chromatography/electrospray ionization ion‐trap tandem mass spectrometry technology. It is validated by the determination of palmitate oxidation by skeletal muscle in lean and obese rats and the regulation by insulin. Resting postabsorptive intramyocellular and plasma palmitate oxidation by the gastrocnemius muscle was determined to be 3.47 ± 0.8 and 2.06 ± 0.5 nmol/g/min in lean and 6.96 ± 1.8 and 1.34 ± 0.2 nmol/g/min in obese rats, respectively. In obese rats, hyperinsulinemia (1 nmol/L) suppressed intramyocellular (by 59 ± 5% to 2.88 ± 0.3 nmol/g/min; p <0.05) but not plasma (1.41 ± 0.14 nmol/g/min; p >0.05) palmitate oxidation. The fractional turnover rate of palmitoylcarnitine (0.34 ± 0.1/min vs. 0.83 ± 0.2/min; p <0.05) was also suppressed by insulin in obese rats. In obese and lean rats, 83 and 51%, respectively (p = 0.08), of plasma fatty acids traverse the triacylglycerol pool before being oxidized. The results demonstrated that the methodology is feasible and sensitive to metabolic alterations and thus can be used to study fatty acid utilization at tissue level in vivo in a compartmentalized manner for the first time.
Endogenous microflora in turbid virgin olive oils and the physicochemical characteristics of these oils
Authors: Koidis Anastasios , Triantafillou Eleftherios , Boskou Dimitrios
Published: January 2008

Cloudy olive oil, the fresh olive juice, is an intermediate form before full precipitation of freshly produced olive oil. Some consumers prefer it because they consider it as more natural and less processed. The cloudy form can persist for several months. The oil is a sort of dispersion/suspension system which can be also described as a micro‐emulsion/suspension. Water micro‐droplets were found to have a size ranging from 1 to 5 µm. Cloudiness is due to the low water content and the presence of natural emulsifiers in the oil. The suspension is formed by solid particles (5–60 µm) deriving from the olive fruit. They are present in small amounts (12–460 mg/kg oil). In the newly produced olive oil, containing 0.17–0.49% water, a number of microorganisms of different types (bacteria, yeasts, moulds) were found to survive, but at very low concentrations (<3 log cfu/mL oil). They originate from the exterior of the fruit (epiphytic microflora) and their presence is considered natural. Their enzyme activities do not seem to affect the quality of the final product.
Using lipid profiles and genotypes for the characterization of Corsican olive oils
Authors: Bronzini de Caraffa Virginie , Gambotti Claude , Giannettini Jean , Maury Jacques , Berti Liliane , Gandemer Gilles
Published: January 2008

In 2004, the Corsican producers of olive oils obtained a French protected designation of origin (PDO) “huile d'olive de Corse”, but up to now specifications of Corsican oil production do not clearly indicate the oil attributes related to the territory of production. That is why the fatty acid and triacylglycerol (TAG) compositions of olive oils from the nine main cultivars used to produce oils under PDO were determined and related to the olive variety. The results showed (i) that the nine cultivars covered only four olive varieties, as revealed by random‐amplified polymorphic DNA markers, (ii) that the lipid composition of oils is strongly dependent on the variety, and (iii) that the lipid composition of the four varieties is completely discriminated on the basis of the proportions of four TAG (OOO, OOL, PoOO, OOL) and one fatty acid (18:0). These results clearly establish the relationships between some characteristics of oils and the area of production (Corsica) for at least three varieties that are originated from Corsica. For the fourth variety, other investigations on minor compounds and on sensory attributes of oils must be undertaken to link some oil traits to the territory of production.
Characterization of virgin olive oil from Southern Tunisia
Authors: Zarrouk Wissem , Haddada Faouzia Mahjoub , Baccouri Bechir , Oueslati Imen , Taamalli Wael , Fernandez Xavier , Lizzani‐Cuvelier Louisette , Daoud Douja , Zarrouk Mokhtar
Published: January 2008

Fruits from three Tunisian cultivars of Olea europea L. grown in the southeast of Tunisia were harvested at the maturity stage of ripeness and immediately processed with a laboratory mill. There are as yet no data on the chemical composition of virgin olive oils from the southeast of Tunisia, an area characterized by an arid condition of growth for olive trees. Our results showed significant differences in the analytical parameters examined for the three cultivars such as fatty acid composition, total phenols and o‐diphenols, and the content of chlorophylls and carotenoids, confirming the importance of genetic factors in the chemical characteristics of the oil. Headspace solid‐phase microextraction (HS‐SPME) was applied to the analysis of volatile compounds of virgin olive oils. Forty‐eight compounds were isolated and characterized by GC‐RI and GC‐MS, representing 94.1–98.1% of the total amount. (E)‐Hex‐2‐enal, the main compound extracted by SPME, characterized the olive oil headspace for all samples. So, it was clearly shown that there were qualitative and quantitative differences in the proportion of volatile constituents from oils of the various cultivars.
Structured lipids from rice bran oil and stearic acid using immobilized lipase from Rhizomucor miehei
Authors: Chopra Rajni , Reddy Sunki Reddy Yella , Sambaiah Kari
Published: January 2008

The major objective of the present study was to prepare structured lipids rich in stearic acid from rice bran oil (RBO) using immobilized lipase (IM 60) from Rhizomucor miehei. The effects of incubation time and temperature, substrate molar ratio, and enzyme load on incorporation of stearic acid were studied. Acidolysis reactions were performed in hexane. Pancreatic lipase‐catalyzed sn‐2 positional analysis and tocopherol analyses were performed before and after enzymatic modification. The kinetics of the reaction was studied and maximum incorporation of stearic acid was observed at 6 h, at 37 °C, when the triacylglycerol and stearic acid molar ratio was maintained at 1 : 6 and the enzyme concentration was 10% of total substrates weight. Stearic acid in RBO after acidolysis was increased from 2.28 to 48.5%, with a simultaneous decrease in palmitic, oleic and linoleic acids. HPLC analysis of tocopherols and tocotrienols was carried out and their content in modified RBO was not significantly affected compared to that of native RBO. The oryzanol content of the modified RBO was reduced from 1.02 to 0.68%. Melting and crystallizing characteristics of the modified fat were studied using differential scanning calorimetry. The total solid fat content at 25 °C increased from 26.12 to 34.8% with an increase in stearic acid incorporation into RBO from 38 to 48%, but it was comparatively less than for cocoa butter and vanaspati. However, the modified RBO completely melted at 37 °C and was useful as plastic fat for various culinary purposes, bakery and confectionary applications. The results of the present study indicated that structured lipids prepared from RBO rich in stearic acid retained their beneficial nutraceuticals; in addition, they do not contain any trans fatty acids.
Determination of total 3‐chloropropane‐1,2‐diol (3‐MCPD) in edible oils by cleavage of MCPD esters with sodium methoxide
Authors: Weißhaar Rüdiger
Published: January 2008

A method for the determination of total 3‐chloropropane‐1,2‐diol (3‐MCPD) in edible fats and oils was presented. 3‐MCPD was released from 3‐MCPD fatty acid esters by transesterification with NaOCH3/methanol. After derivatization with phenylboronic acid, 3‐MCPD was determined by GC‐MS. Deuterium‐labeled 3‐MCPD was used as internal standard. In a model experiment, it was shown that acidic hydrolysis with methanol/sulfuric acid, which is normally used for the release of 3‐MCPD from its esters, can cause problems because under acidic conditions additional 3‐MCPD can be formed. No additional 3‐MCPD was formed using NaOCH3/methanol for transesterification. Eleven samples of cold‐pressed and refined safflower oils were analyzed with this method. Levels of total 3‐MCPD were in the range from <100 up to 3200 µg/kg.
Volatile compounds and triacylglycerol composition of original Indian fatty plant oils
Authors: Krist Sabine , Stuebiger Gerald , Bail Stefanie , Unterweger Heidrun
Published: January 2008

Some typical original Indian edible and non‐edible fatty plant oils were subject of our investigations. Fundamental research was done on analyzing volatile compounds using HS‐SPME‐GC‐MS. In addition, a sensorial evaluation was applied to receive data on the smell of the samples. Furthermore, the typical and prevailing triacylglycerols (TAG) were investigated by MALDI‐TOF‐MS. Mass spectra reflect the TAG profiles of the whole oil samples based on the detection of [M+Na]+ ions. Oil samples exhibit quite unique TAG profiles, which are suitable for rapid characterization of the original plant oils. The fatty acid composition of the corresponding TAG structures was calculated using lipid analysis software based on the known fatty acid composition. Relative quantification of TAG components was in good agreement with the literature, in case appropriate data are available so far.
Chicken fat dry fractionation: Effects of temperature and time on crystallization, filtration and fraction properties
Authors: Arnaud Elodie , Collignan Antoine
Published: January 2008

A surface response experimental design was used to quantify the effects of the final cooling temperature and the residence time at this temperature on the filtration characteristics of the crystal suspension and the quality of the fractions during chicken fat dry fractionation. The crystal morphology was monitored to gain insight into the observed effects. Temperature affected crystallization and the characteristics of the olein and stearin fractions. The crystals became fragmented as the residence time increased, thus leading to a decrease in the filterability of the crystal suspension and an increase in the proportion of the entrained liquid phase. The residence time only affected the quality of the stearin fraction. This time effect was noted at high cooling temperatures in the investigated experimental domain. At low temperatures, increasing the residence time enhanced crystal growth and increased the extent of unsaturation of both fractions without modifying the filtration features.
Improvement of microemulsion electrokinetic chromatography for measuring octanol–water partition coefficients
Authors: Xia Zhining , Jiang Xuemei , Mu Xiaojing , Chen Hua
Published: January 2008

Microemulsion electrokinetic chromatography (MEEKC) has been used to indirectly measure octanol–water partition coefficients (log Pow) of compounds. In order to obtain an accurate log Pow value, the electrophoretic mobilities of the microemulsion phase (μme) and the analyte (μeff) in MEEKC must be accurately required. However, in conventional MEEKC, the shortage of obtaining μme with a tracing method was discovered, and the influences of concentration, injection volume of analyte, and high electric field on measuring μeff were also found. In this paper, a novel method called improved MEEKC (I‐MEEKC) was developed to avoid the problems mentioned above. In I‐MEEKC, a nonlinearity fitting program was used to obtain μme to avoid the error from tracing μme; the extrapolating method was used to eliminate the effects of concentrations and injection volumes of analytes on μeff measurement, and an enough stable microemulsion was selected to eliminate the effect of high electric field on μeff measurement. Then the novel method was applied to estimate log Pow of uncharged compounds and charged pharmaceuticals compared to the conventional MEEKC. The log Pow of all analytes obtained by I‐MEEKC agreed with those obtained by classical shake flask or literature values, the errors between them were within 0.1 logarithm units, better than the ones by conventional MEEKC.
Novel open tubular CEC with tentacle‐type polymer stationary phase functionalized by phenylalanine
Authors: Xu Liang , Sun Yan
Published: January 2008

A novel stationary phase with tentacle‐type polymer chains with epoxy groups was fabricated for open tubular CEC. The fabrication procedure of the stationary phase included pretreatment of capillary inner wall, silanization, and glycidyl methacrylate (GMA)‐grafted polymerization. The influence of initiator concentration and polymerization time on the resulting polymer stationary phase was studied by measuring EOF mobility and hydrophobicity of the prepared capillary column. SEM showed that the capillary inner wall was evenly coated with a polymer film showing a wrinkly surface. The prepared GMA‐grafted stationary phase could be easily modified with different chromatographic ligands by the ring‐opening reaction of the epoxy groups. In this study, phenylalanine (Phe) was selected as the ligand. Benzene derivatives and three amino acids were then separated, respectively, using the Phe modified tentacle‐type capillary column. As a control, separations were also performed on a monolayer Phe‐modified capillary. The tentacle‐type polymer stationary phase was found affording stronger retention and better resolution in the separation of benzene derivatives and tryptophan, tyrosine, and Phe mixtures compared with the monolayer stationary phase.
Fabrication of molecularly imprinted hybrid monoliths via a room temperature ionic liquid‐mediated nonhydrolytic sol–gel route for chiral separation of zolmitriptan by capillary electrochromatography
Authors: Wang He‐Fang , Zhu Yi‐Zhou , Lin Jian‐Ping , Yan Xiu‐Ping
Published: January 2008

A room temperature ionic liquid (RTIL)‐mediated nonhydrolytic sol–gel (NHSG) protocol was explored for the fabrication of new molecularly imprinted silica‐based hybrid monoliths for chiral separation of a basic template zolmitriptan by CEC. The RTIL‐mediated NHSG protocol involved free‐radical copolymerization and NHSG process. Three carboxylic acids (trifluoromethyl acrylic acid, cinnamic acid, and methacrylic acid (MAA)) were examined as both the functional monomers and the catalysts for the NHSG condensation of methacryloxypropyltrimethoxysilane (MPTMS) to form silica‐based framework. RTIL was incorporated to reduce gel shrinkage and also to act as the pore template. The effects of carboxylic acids and RTIL on the performance of the silica‐based hybrid molecularly imprinted polymer (MIP) monoliths were investigated in detail to realize excellent chiral recognition and to give new insights into the mechanism of the RTIL‐mediated NHSG strategy. Excellent chiral separation of (R)/(S)‐zolmitriptan was achieved when the molar ratio of MAA to MPTMS was 1:4 and 1:2 with RTIL involved. The synergism of the free‐radical copolymerization of the C=C bond of carboxylic acids and MPTMS with the NHSG condensation of MPTMS catalyzed by the carboxylic acids was demonstrated. The incorporation of RTIL increased porosity, and hence improved selectivity of the prepared hybrid monoliths.
A sweeping‐micellar electrokinetic chromatography method for direct detection of some aromatic amines in water samples
Authors: Zhang Jianhua , Wu Xiaoping , Zhang Wei , Xu Liangjun , Chen Guonan
Published: January 2008

A simple and rapid sweeping method for the online improvement of detection limit of some aromatic amines has been developed in this work. The optimum sweeping and separation conditions for 4‐methylaniline, 3,4‐dichloroaniline, 4‐chloroaniline, and 4‐aminophenyl were investigated in detail. Under the optimum conditions, the detection limits of these four aromatic amines ranged from 5.4×10−10 to 4.6×10−8 mol/L (S/N = 3), which was about 80–1090‐folds lower than those of conventional sample injections. Linear response range were in the range of 2.5×10−8–2.0×10−6 mol/L with the correlation coefficient between 0.9965 and 0.9994. Baseline separation was achieved within 10 min. After validation, the developed method was applied to determine 4‐methylaniline, 3,4‐dichloroaniline, 4‐chloroaniline, and 4‐aminophenyl in river water sample with average recoveries of 79.6–88.7%.
Cloud point extraction combined with micellar electrokinetic capillary chromatography determination of benzophenones in cosmetic matrix
Authors: Wu Yi‐Wei , Jiang Yin‐Yan , liu Jun‐Feng , Xiong Kun
Published: January 2008

A method has been developed for the separation and determination of three hydrophobic benzophenones: 2,4‐dihydroxybenzophenone (BP‐1), 2,2′4,4′‐tetrahydroxybenzophenone (BP‐2), and 2‐hydroxy‐4‐methoxybenzophenone (BP‐3) in sunscreen by micellar electrokinetic capillary chromatography (MEKC) combined with cloud point extraction (CPE). The analytes were extracted at pH 5.0 by micelles of the nonionic surfactant polyoxyethylene‐7.5‐octylphenyl ether (Triton X‐114). A 150 μL aliquot from the extracted surfactant‐rich phase was diluted up to 500 μL with ethanol to reduce its viscosity before separation by MEKC. A background electrolyte of 25 mmol/L sodium tetraborate containing 30 mmol/L sodium dodecyl sulfate at pH 9.25 was used as the separation medium to avoid the adsorption of hydrophobic substances and Triton X‐114 onto the inner surface of the separation capillary, ensuring the separation efficiency and reproducibility. Detection is performed at 290 nm. Under the optimized conditions, an enrichment factor of 20 was obtained and the determination limits of BP‐1, BP‐2, and BP‐3 were found to be 3.90×10−7, 3.83×10−7, and 6.42×10−8 mol/L, respectively. In comparison with the earlier reported methods, the LODs of this method are superior to the other methods. The presented procedure was successfully applied to the determination of BP‐1, BP‐2, and BP‐3 in sunscreen with satisfactory results.
Continuum transport model of Ogston sieving in patterned nanofilter arrays for separation of rod‐like biomolecules
Authors: Li Zi Rui , Liu Gui Rong , Chen Yu Zong , Wang Jian‐Sheng , Bow Hansen , Cheng Yuan , Han Jongyoon
Published: January 2008

This article proposes a simple computational transport model of rod‐like short dsDNA molecules through a microfabricated nanofilter array. Using a nanochannel consisting of alternate deep wells and shallow slits, it is demonstrated that the complex partitioning of rod‐like DNA molecules of different sizes over the nanofilter array can be well described by continuum transport theory with the orientational entropy and anisotropic transport parameters properly quantified. In this model, orientational entropy of the rod‐like DNA is calculated from the equilibrium distribution of rigid cylindrical rod near the solid wall. The flux caused by entropic differences is derived from the interaction between the DNA rods and the solid channel wall during rotational diffusion. In addition to its role as an entropic barrier, the confinement of the DNA in the shallow channels also induces large changes in the effective electrophoretic mobility for longer molecules in the presence of EOF. In addition to the partitioning/selectivity of DNA molecules by the nanofilter, this model can also be used to estimate the dispersion of separated peaks. It allows for fast optimization of nanofilter separation devices, without the need of stochastic modeling techniques that are usually required.
Prolonged‐release performance of perfume encapsulated by tailoring mesoporous silica spheres
Authors: Wang Ping , Zhu Yihua , Yang Xiaoling , Chen Aiping
Published: January 2008

Mesoporous silica (MS) spheres with size‐controllable pore channels and regular spherical shape were used as supports for the encapsulation of hydrophilic perfume. The MS spheres were tailored by expanding pore size in order to have high loading content. The perfume‐encapsulating MS spheres so obtained were followed by assembling 10 layers of polyelectrolyte shell on the microspheres' surfaces for the purpose of good prolonged‐release performance. The morphologies and prolonged‐release performance of perfume‐encapsulating MS spheres with 10‐layer polyelectrolyte shells were characterized by transmission electron microscopy, pore size analysis, thermogravimetric analysis and UV‐vis and FTIR spectroscopy. The results showed that with MS spheres constructed in this way, effective prolonged‐release performance can be achieved. We also demonstrated that these MS spheres can indeed be used for the prolonged release of perfume. Copyright © 2008 John Wiley & Sons, Ltd.
GC–MS, GC–O and enantio–GC investigation of the essential oil of Tarchonanthus camphoratus L.
Authors: Costa Rosaria , d'Acampora Zellner Barbara , Crupi Maria L. , Fina Maria R. De , Valentino Maria R. , Dugo Paola , Dugo Giovanni , Mondello Luigi
Published: January 2008

The volatile fraction of Tarchonanthus camphoratus L. has been studied by means of gas chromatography–mass spectrometry (GC–MS) and GC–FID, leading to the determination of 90 components whose major were α‐pinene (14.7 g/100 g), eucalyptol (14.8 g/100 g) and fenchyl alcohol (12.2 g/100 g). Gas chromatography–olfactometry (GC–O) has been applied to the evaluation of the olfactive notes and their intensity. Also, the enantiomeric distribution of some relevant constituents has been assessed by enantio‐GC through the use of a chiral cyclodextrin‐based stationary phase. Copyright © 2008 John Wiley & Sons, Ltd.
Modelling perfume deposition on fabric during a washing cycle: theoretical approach
Authors: Normand Valéry , Tang Jane , Struillou Arnaud
Published: January 2008

The effect of surfactant micelles on the deposition of perfume molecules on fabric has been estimated theoretically for a full washing cycle, using mass transfer mechanisms. In the absence of a surfactant phase, the fraction of fragrance molecules deposited on fabric is well characterized by a sigmoidal curve with the logP value of the perfume molecules, which is a well‐known result. However, when surfactant is added at a concentration higher than the critical micellar concentration (CMC), high logP value molecules are lost, due to the hydrophobic phase created by the micelles. This phenomenon results in a modified sigmoidal behaviour of the fraction of fragrance molecules deposited, with the logP value that tends to reach the zero deposition for very high logP values. A maximum fraction deposited is located at intermediate logP values (between 1.5 and 3). Evidence of redeposition of high logP value molecules is shown when rinsing is considered. In this case, the micelles break if the overall surfactant concentration is below the CMC, and the trapped perfume molecules are released and are able to deposit on the fabric. This model is successfully subjected to measured performance of the key raw perfume materials. Copyright © 2008 John Wiley & Sons, Ltd.
Aroma‐active compounds of Elsholtzia splendens using AEDA and HS–SPME–GC–O dilution analysis
Authors: Choi Hyang S. , Min Kyung C.
Published: January 2008

This study was conducted to determine the composition of essential oil and headspace from Elsholtzia splendens, and to determine the aroma‐active compounds of this aromatic plant. Eighty‐five components were identified in the oil by GC and GC–MS. The major compounds were naginata ketone (70.43%) and elsholtzia ketone (4.95%). Sixty‐eight volatile flavour constituents were detected in the headspace of this herb, and geranyl acetate (4.48%) was the most abundant component. Flavour dilution (FD) factors were evaluated by aroma extract dilution analysis with gas chromatography–olfactometry (GC–O). Naginata ketone, α‐pinene, elsholtzia ketone, carvone oxide and geraniol showed high FD‐factors (≥5). Naginata ketone, geraniol, elsholtzia ketone, carvone oxide and geranyl acetate were regarded as the characteristic odour components of the essential oil by the sniffing test. Especially, naginata ketone and geraniol were considered as most similar odour components to Elsholtzia splendens by organoleptic evaluation with GC–O. Naginata ketone, nerol, geraniol and carvone oxide were considered as having a Elsholtzia splendens‐like odour by headspace solid‐phase microextraction GC–O (HS–SPME–GC–O) dilution analysis. Naginata ketone was the most intensive compound in HP–SPME–GC–O dilution analysis by varying the fibre length, and naginata ketone and geraniol were the aroma‐active compounds in HS–SPME–GC–O dilution analysis by varying the GC split ratio. Copyright © 2008 John Wiley & Sons, Ltd.
The t(1;9)(p34;q34) and t(8;12)(p11;q15) fuse pre‐mRNA processing proteins SFPQ (PSF) and CPSF6 to ABL and FGFR1
Authors: Hidalgo‐Curtis Claire , Chase Andrew , Drachenberg Milton , Roberts Mark W. , Finkelstein Jerry Z. , Mould Sarah , Oscier David , Cross Nicholas C. P. , Grand Francis H.
Published: January 2008

We have investigated two patients with acquired chromosomal rearrangements, a male presenting with a t(1;9)(p34;q34) and B cell progenitor acute lymphoid leukemia and a female presenting with a t(8;12)(p11;q15) and the 8p11 myeloproliferative syndrome. We determined that the t(1;9) fused ABL to SFPQ (also known as PSF), a gene mapping to 1p34 that encodes a polypyrimidine tract‐binding protein‐associated splicing factor. The t(8;12) fused CPSF6, a cleavage and polyadenylation specificity factor, to FGFR1. The fusions were confirmed by amplification of the genomic breakpoints and RT‐PCR. The predicted oncogenic products of these fusions, SFPQ‐ABL and CPSF6‐FGFR1, are in‐frame and encode the N‐terminal domain of the partner protein and the entire tyrosine kinase domain and C‐terminal sequences of ABL and FGFR1. SFPQ interacts with two FGFR1 fusion partners, ZNF198 and CPSF6, that are functionally related to the recurrent PDGFRα partner FIP1L1. Our findings thus identify a group of proteins that are important for pre‐mRNA processing as fusion partners for tyrosine kinases in hematological malignancies. © 2008 Wiley‐Liss, Inc.
Relationship uncertainty linkage statistics (RULS): affected relative pair statistics that model relationship uncertainty
Authors: Ray Amrita , Weeks Daniel E.
Published: January 2008

Linkage analysis programs invariably assume that the stated familial relationships are correct. Thus, it is common practice to resolve relationship errors by either discarding individuals with erroneous relationships or using an inferred alternative pedigree structure. These approaches are less than ideal because discarding data is wasteful and using inferred data can be statistically unsound. We have developed two linkage statistics that model relationship uncertainty by weighting over the possible true relationships. Simulations of data containing relationship errors were used to assess our statistics and compare them to the maximum‐likelihood statistic (MLS) and the Sall non‐parametric LOD score using true and discarded (where problematic individuals with erroneous relationships are discarded from the pedigree) structures. We simulated both small pedigree (SP) and large pedigree (LP) data sets typed genome‐wide. Both data sets have several underlying true relationships; SP has one apparent relationship—full sibling—and LP has several different apparent relationship types. The results show that for both SP and LP, our relationship uncertainty linkage statistics (RULS) have power nearly as high as the MLS and Sall using the true structure. Also, the RULS have greater power to detect linkage than the MLS and Sall using the discarded structure. For example, for the SP data set and a dominant disease model, both the RULS had power of about 93%, while Sall and MLS have 90% and 83% power on the discarded structure. Thus, our RULS provide a statistically sound and powerful approach to the commonly encountered problem of relationship errors. Genet. Epidemiol. © 2008 Wiley‐Liss, Inc.
Remodeling of motor nerve terminals in demyelinating axons of periaxin‐null mice
Authors: Court Felipe A. , Brophy Peter J. , Ribchester Richard R.
Published: January 2008

Myelin formation around axons increases nerve conduction velocity and influences both the structure and function of the myelinated axon. In the peripheral nervous system, demyelinating forms of hereditary Charcot‐Marie‐Tooth (CMT) diseases cause reduced nerve conduction velocity initially and ultimately axonal degeneration. Several mouse models of CMT diseases have been generated, allowing the study of the consequences of disrupting Schwann cell function on peripheral nerve fibers. Nevertheless, the effect of demyelination at the level of the neuromuscular synapse has been largely overlooked. Here we show that in mice lacking functional Periaxin (Prx) genes, a model of a recessive type of CMT disease known as CMT4F, neuromuscular junctions (NMJs) develop profound morphological changes in the preterminal region of motor axons. These changes include extensive preterminal branches that originate in demyelinated regions of the nerve fiber and axonal swellings associated with residually‐myelinated regions of the fiber. Using intracellular recording from muscle fibers we detected asynchronous failure of action potential transmission at high but not low stimulation frequencies, a phenomenon consistent with branch point failure. Taken together, our morphological and electrophysiological findings suggest that preterminal branching due to segmental demyelination near the neuromuscular synapse in Periaxin KO mice may underlie some characteristics of disabilities, including coordination deficits, present in this mouse model of CMT disease. These results reveal the importance of studying how demyelinating diseases might influence NMJ function and contribute to clinical disability. © 2008 Wiley‐Liss, Inc.
The protective effects of 15‐deoxy‐Δ‐12,14‐prostaglandin J2 in spinal cord injury
Authors: Kerr Bradley J. , Girolami Elizabeth I. , Ghasemlou Nader , Jeong Suh Young , David Samuel
Published: January 2008

Secondary tissue damage that occurs within days after spinal cord injury contributes significantly to permanent paralysis, sensory loss, and other functional disabilities. The acute inflammatory response is thought to contribute largely to this secondary damage. We show here that 15‐deoxy‐Δ‐12,14‐prostaglandin J2 (15d‐PGJ2), a metabolite of prostaglandin D2 (PGD2) that has anti‐inflammatory actions, given daily for the first 2 weeks after spinal cord contusion injury in mice, results in significant improvement of sensory and locomotor function. 15d‐PGJ2‐treated mice also show diminished signs of microglia/macrophage activation, increased neuronal survival, greater serotonergic innervation, and reduced demyelination in the injured spinal cord. These changes are accompanied by a reduction in chemokine and pro‐inflammatory cytokine expression. Our results also indicate that 15d‐PGJ2 is likely to reduce inflammation in the injured spinal cord by attenuating multiple signaling pathways: reducing activation of NF‐κB; enhancing expression of suppressor of cytokine signaling1 and reducing the activation of Janus activated Kinase 2. © 2008 Wiley‐Liss, Inc.
Characterization and transformation potential of “Synthetic” astrocytes differentiated from murine embryonic stem cells
Authors: Kamnasaran Deepak , Hawkins Cynthia , Guha Abhijit
Published: January 2008

Our objective was to determine if murine embryonic stem (ES) cells, which are readily available from repositories, could be developed as a model of gliomagenesis, recognizing the difficulty in obtaining and transforming somatic astrocytes. Using a stringently controlled sequential differentiation procedure on wild type (wt) and p53+/− ES cells, we established GFAP+A2B5‐synthetic astrocytes with high efficiency (>90%). The synthetic astrocytes stably express several differentiated astrocyte associated structural proteins and biochemical markers, but lacked expression of differentiated neurons and oligodendrocytes. However, in contrast to somatic differentiated astrocytes, the synthetic astrocytes expressed stem cell markers, with a transcriptome profile similar to astrocytes differentiated from neural stem cells (NSC) and somatic astrocyte cultures established from E13.5‐Cortex and P4‐hippocampus. In addition, the synthetic astrocytes demonstrated plasticity, with ability to dedifferentiate into neuronal and oligodendrocyte lineages. Intracranial injection of postnatal differentiated somatic astrocytes or synthetic astrocytes of either wt or p53+/− background did not grow tumors, unlike corresponding ES cells that develop teratomas. In contrast, retroviral transduction of either wt or p53+/− synthetic astrocytes and not the postnatal somatic astrocytes, with relevant oncogenes found in human malignant astrocytomas (MDM2, myr‐AKT, V12H‐RAS), led to intracranial high‐grade undifferentiated gliomas. This study demonstrates utilization of readily available ES cells of varying genetic backgrounds to model and further our understanding of gliomagenesis. Large numbers of replenishable derivative synthetic glial lineage cells retain genetic and phenotypic characteristics of progenitor cells and thereby are more amenable to transformation by genetic aberrations involved in gliomagenesis. © 2008 Wiley‐Liss, Inc.