bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of boron‐containing materials on the flammability and thermal degradation of polyamide 6 composites containing melamine
Authors: Doğan Mehmet , Bayramlı Erdal
Published: June 2010

Three different boron‐containing substances—zinc borate (ZnB), borophosphate (BPO4), and a boron‐ and silicon‐containing oligomer (BSi)—were used to improve the flame retardancy of melamine in a polyamide 6 (PA‐6) matrix. The combustion and thermal degradation characteristics of PA‐6 composites were investigated with the limiting oxygen index (LOI), the UL‐94 standard, thermogravimetric analysis (TGA)/Fourier transform infrared (FTIR) spectroscopy, and differential scanning calorimetry (DSC). A slight increase was seen in the LOI values of a sample containing BSi (1 wt %). BPO4 at high loadings showed a V0 rating (indicating the best flame retardancy) and slightly lower LOI values in comparison with samples with only melamine. For ZnB and BSi, glassy film and char formation decreased the dripping rate and sublimation of melamine, and this led to low LOIs. According to the TGA–FTIR results, the addition of boron compounds did not change the decomposition product distribution of melamine and PA‐6. The addition of boron compounds affected the flame retardancy by physical means. The TGA data showed that boron compounds and melamine reduced the decomposition temperature of PA‐6. According to the DSC data, the inclusion of boron compounds increased the onset temperature of sublimation of melamine and also affected the flame retardancy negatively. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Pigment dyeing of polyamide‐epichlorohydrin cationized cotton fabrics
Authors: Fang Kuanjun , Zhang Lianbing , Xu Yi , Zhang Xia
Published: June 2010

A synthesized cationic reagent named polyamide‐epichlorohydrin (PAE) was used to cationize cotton fabrics which were dyed with nanoscale pigments after PAE modification. The results showed that when the PAE concentration was below 7% (owf), the K/S value increased nearly linearly with increasing of PAE concentration, and excess that concentration the K/S value did not increase further. With increasing the pH value of cationization bath, the K/S value increased first and then decreased, the maximum K/S value appeared at pH 9–10. Cotton fabrics cationized at 80°C for 20 min exhibited the best cationizing result. Both the pigment uptake and the color strength reached their own maximum values when the dye bath was neutral. When the pigment concentration was 1% (owf) the addition of 1g/L sodium chloride in the dye bath could decrease the pigment uptake while for 5% (owf) pigment concentration the uptake increased with increasing the amount of sodium chloride. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Improvement in voltage, thermal, mechanical stability and ion transport properties in polymer‐clay nanocomposites
Authors: Sharma A. L. , Thakur Awalendra K.
Published: June 2010

We report novel results on optimization of intercalated polymer‐clay nanocomposite endowed with desirable properties like, (i) very high ionic conductivity (∼ 10−3 S cm−1) at room temperature, (ii) substantial improvement in voltage stability (∼ 5.6 V), mechanical stability (25 MPa), and thermal stability (250°C) (iii) tion ∼ 99% and cation transport number (tLi+) ∼ 67%: Intercalation of polymer salt (PAN)8LiCF3SO3 complex into dodecylamine modified montmorillonite clay (DMMT) nanometric channels has been confirmed by X‐ray diffraction and Transmission electron microscopy analysis. Complex impedance spectroscopy suggests bulk electrical conduction in the high frequency region and electrode polarization effect at the low frequencies. The experimental value of conductivity, voltage, and mechanical stability is observed to be invariably higher in polymer nanocomposite film when compared with clay free polymer‐salt complex film. The same is true for cation transport. The optimized polymer film serves dual purpose of electrolyte and separator in energy storage devices. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Study on the properties of magnetorheological gel based on polyurethane
Authors: Wei Bing , Gong Xinglong , Jiang Wanquan , Qin Lijun , Fan Yanceng
Published: June 2010

Magnetorheological gels (MRGs) known as a new kind of magnetorheological material are composite gels containing magnetic particles suspended in polymer gels. In this study, a category of MR polymer gels based on polyurethane (PU) were prepared. The microstructures of these MRGs were observed with a digital microscope. Their rheological properties under both steady shear and oscillation testing were characterized by using a MR rheometer. The viscosity of the PU MRG decreased with the increment of NCO/OH ratio and increased with the increment of the weight concentration of carbonyl iron particles, molecular mass of poly propylene glycol, and applied magnetic field. The storage modulus increased gradually with the increment of applied magnetic field and weight concentration of carbonyl iron particles. The PU MRG exhibits high static shear yield stress (60.8 kPa, at 573 mT) and dynamic shear yield stress (83.9 kPa, at 573 mT) and wide variation range (static shear yield stress: 6–62 kPa, dynamic shear yield stress: 15–85 kPa). These advantages indicate that PU MRG is able to satisfy wide applications. In addition, both static and dynamic shear yield stresses of the MRG samples increase with the increment of molar mass of polypropylene glycol. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
The demography of introduction pathways, propagule pressure and occurrences of non‐native freshwater fish in England
Authors: Copp G. H. , Vilizzi L. , Gozlan R. E.
Published: June 2010

Biological invasion theory predicts that the introduction and establishment of non‐native species is positively correlated with propagule pressure. Releases of pet and aquarium fishes to inland waters has a long history; however, few studies have examined the demographic basis of their importation and incidence in the wild.

For the 1500 grid squares (10×10 km) that make up England, data on human demographics (population density, numbers of pet shops, garden centres and fish farms), the numbers of non‐native freshwater fishes (from consented licences) imported in those grid squares (i.e. propagule pressure), and the reported incidences (in a national database) of non‐native fishes in the wild were used to examine spatial relationships between the occurrence of non‐native fishes and the demographic factors associated with propagule pressure, as well as to test whether the demographic factors are statistically reliable predictors of the incidence of non‐native fishes, and as such surrogate estimators of propagule pressure.

Principal coordinates of neighbour matrices analyses, used to generate spatially explicit models, and confirmatory factor analysis revealed that spatial distributions of non‐native species in England were significantly related to human population density, garden centre density and fish farm density. Human population density and the number of fish imports were identified as the best predictors of propagule pressure.

Human population density is an effective surrogate estimator of non‐native fish propagule pressure and can be used to predict likely areas of non‐native fish introductions. In conjunction with fish movements, where available, human population densities can be used to support biological invasion monitoring programmes across Europe (and perhaps globally) and to inform management decisions as regards the prioritization of areas for the control of non‐native fish introductions.

© Crown copyright 2010. Reproduced with the permission of her Majesty's Stationery Office. Published by John Wiley & Sons, Ltd.
Detecting North American signal crayfish (Pacifastacus leniusculus) in riffles
Authors: Gladman Z. F. , Yeomans W. E. , Adams C. E. , Bean C. W. , McColl D. , Olszewska J. P. , McGillivray C. W. , McCluskey R.
Published: June 2010

The spread of the invasive signal crayfish (Pacifastacus leniusculus) outside its natural range is of widespread concern due to the threats posed to native biodiversity. To date, there is no standard protocol for determining signal crayfish presence or absence in a watercourse.

For the purposes of this investigation, the crayfish detection ability of active sampling methods — hand‐netting, electrofishing (one, two and three runs), kick sampling and Surber sampling — was tested at 30 sites along the River Clyde, southern central Scotland.

No single technique was successful in detecting crayfish in 100% of the sites known to contain crayfish and so the application of combinations of techniques was considered. The combination of techniques that resulted in a 100% detection rate was electrofishing (three runs) together with kick sampling. These results suggest that three‐run electrofishing and kick sampling are the best candidates for incorporation into a crayfish detection protocol.

The mean time taken to apply electrofishing (three runs) was significantly greater than the mean time to apply kick sampling. Given the lower effort required for its application, kick sampling is recommended as the preliminary technique: if kick sampling yields a negative result, the application of electrofishing will decrease the chance of recording a false negative presence. If both kick sampling and electrofishing fail to detect crayfish, trapping may further decrease the risk of a false negative result.

These findings have assisted in the development of a crayfish detection protocol, which will be applied across Scotland to determine the current distribution of signal crayfish. Copyright © 2010 John Wiley & Sons, Ltd.
Inhibitors of p38 suppress cytokine production in rheumatoid arthritis synovial membranes: Does variable inhibition of interleukin‐6 production limit effectiveness in vivo?
Authors: Page Theresa H. , Brown Anthony , Timms Emma M. , Foxwell Brian M. J. , Ray Keith P.
Published: June 2010

Objective

The activity of p38 MAPK regulates lipopolysaccharide (LPS)–stimulated production of key proinflammatory cytokines such as tumor necrosis factor α (TNFα). Consequently, p38 MAPK inhibitors have attracted considerable interest as potential treatments of rheumatoid arthritis (RA), and studies in murine models of arthritis have yielded promising results. However, the performance of several compounds in human clinical trials has been disappointing. At present, the reason for this poor performance is unclear. The aim of this study was to examine the effects of p38 inhibitors on both diseased and normal human tissue and cells, in order to test whether this kinase still plays a critical role in cytokine production under conditions of chronic inflammation.

Methods

Proinflammatory and antiinflammatory cytokine production was monitored after treatment of primary human monocytes, macrophages, and RA synovial membrane cultures with p38 MAPK inhibitor compounds. The following 3 inhibitors were used in these studies: SB‐203580 (inhibits the α and β isoforms), BIRB‐796 (inhibits the α, β, γ, and δ isoforms), and a novel, structurally distinct p38 MAPK inhibitor, SB‐731445 (inhibits the α and β isoforms).

Results

SB‐731445 and SB‐203580 produced profound inhibition of spontaneous production of proinflammatory cytokines (TNFα and interleukin‐1 [IL‐1]) in both RA membrane cultures and LPS‐stimulated primary human monocytes. However, this and other p38 MAPK inhibitors produced a significant increase in IL‐6 production by LPS‐stimulated primary human macrophages and a decrease in IL‐10 production by all cell types examined.

Conclusion

The potentially proinflammatory consequences of these activities (decreased IL‐10 production and increased IL‐6 production) may offer some explanation for the inability of p38 MAPK inhibitors to provide the therapeutic benefit that had been hoped for in RA.
MicroRNA‐125a contributes to elevated inflammatory chemokine RANTES levels via targeting KLF13 in systemic lupus erythematosus
Authors: Zhao Xia , Tang Yuanjia , Qu Bo , Cui Huijuan , Wang Shujun , Wang Lijia , Luo Xiaobing , Huang Xinfang , Li Jia , Chen Shunle , Shen Nan
Published: June 2010

Objective

MicroRNA (miRNA) have received increasing attention as posttranscriptional regulators that fine‐tune the homeostasis of the inflammatory response. This study aimed to clarify whether miR‐125a, which was identified in a pilot expression profiling step, is involved in the inflammatory chemokine pathway in systemic lupus erythematosus (SLE).

Methods

Independent verification of miR‐125a expression in amplified samples from SLE patients and normal controls was performed by TaqMan quantitative polymerase chain reaction (PCR) analysis. A combination of 3 bioinformatic prediction techniques and reporter gene assays was used to identify miR‐125a targets. In vitro systems of overexpression by transfection and inducible expression by stimulation were performed to investigate the function of miR‐125a, which was followed by real‐time quantitative PCR and enzyme‐linked immunosorbent assay.

Results

In SLE patients, the expression of miR‐125a was reduced and the expression of its predicted target gene, KLF13, was increased. Bioinformatics predicted that miR‐125a base‐paired with sequences in the 3′‐untranslated region of KLF13. Overexpression of miR‐125a led to a significant reduction in the expression of RANTES and KLF13. MicroRNA‐125a inhibited endogenous KLF13 expression in a dose‐dependent manner, as determined using gain‐ and loss‐of‐function methods. A luciferase reporter system confirmed the miR‐125a binding sites. Notably, miR‐125a expression was induced in T cells in a dose‐ and time‐dependent manner. Finally, the introduction of miR‐125a into T cells from SLE patients alleviated the elevated RANTES expression.

Conclusion

MicroRNA‐125a negatively regulates RANTES expression by targeting KLF13 in activated T cells. The underexpression of miR‐125a contributes to the elevated expression of RANTES in SLE. Our findings extend the role of miRNA in the pathogenesis of lupus and provide potential strategies for therapeutic intervention.
Tuning the Stability and Reactivity of Metal‐bound Alkylperoxide by Remote Site Substitution of the Ligand
Authors: Hikichi Shiro , Kobayashi Chiho , Yoshizawa Michito , Akita Munetaka
Published: June 2010

An alkylperoxonickel(II) complex with hydrotris(3,5‐diisopropyl‐4‐bromo‐1‐pyrazolyl)borate, [NiII(OOtBu)(TpiPr2,Br)] (3a), is synthesized, and its chemical properties are compared with those of the prototype non‐brominated ligand derivative [NiII(OOtBu)(TpiPr2)] (3b; TpiPr2=hydrotris(3,5‐diisopropyl‐1‐pyrazolyl)borate). Same synthetic procedures for the prototype 3b and its precursors can be employed to the synthesis of the TpiPr2,Br analogues. The dimeric nickel(II)‐hydroxo complex, [(NiIITpiPr2,Br)2(μ‐OH)2] (2a), can be synthesized by the base hydrolysis of the labile complexes [NiII(Y)(TpiPr2,Br)] (Y=NO3 (1a), OAc (1a′)), which are obtained by the metathesis of NaTpiPr2,Br with the corresponding nickel(II) salts, and the following dehydrative condensation of 2a with the stoichiometric amount of tert‐butylhydroperoxide yields 3a. The unique structural characteristics of the prototype 3b, that is, highly distorted geometry of the nickel center and intermediate coordination mode of the OO moiety between η1 and η2, are kept in the brominated ligand analogue 3a. The introduction of the electron‐withdrawing substitutents on the distal site of TpR affects the thermal stability and reactivity of the nickel(II)‐alkylperoxo species.
More than maths and mindreading: Sex differences in empathizing/systemizing covariance
Authors: Valla Jeffrey M. , Ganzel Barbara L. , Yoder Keith J. , Chen Grace M. , Lyman Laura T. , Sidari Anthony P. , Keller Alex E. , Maendel Jeffrey W. , Perlman Jordan E. , Wong Stephanie K.L. , Belmonte Matthew K.
Published: June 2010

Empathizing–Systemizing theory posits a continuum of cognitive traits extending from autism into normal cognitive variation. Covariance data on empathizing and systemizing traits have alternately suggested inversely dependent, independent, and sex‐dependent (one sex dependent, the other independent) structures. A total of 144 normal undergraduates (65 men, 79 women) completed the Reading the Mind in the Eyes, Embedded Figures, and Benton face recognition tests, the Autism Spectrum Quotient, and measures of digit length ratio and field of study; some also completed tests of motion coherence threshold (64) and go/no‐go motor inhibition (128). Empathizing and systemizing traits were independent in women, but largely dependent in men. In men, level of systemizing skill required by field of study was directly related to social interactive and mindreading deficits; men's social impairments correlated with prolonged go/no‐go response times, and men tended to apply systemizing strategies to solve problems of empathizing or global processing: rapid perceptual disembedding predicted heightened sensitivity to facial emotion. In women, level of systemizing in field was related to male‐typical digit ratios and autistic superiorities in detail orientation, but not to autistic social and communicative impairments; and perceptual disembedding was related to social interactive skills but independent of facial emotion and visual motion perception.
Role for antibodies in altering behavior and movement
Authors: Libbey Jane E. , Fujinami Robert S.
Published: June 2010

At the past meeting of INSAR, the role of autoimmunity was discussed in an educational session. This article summarizes this discussion. In immune‐mediated diseases, antibodies can contribute to the pathogenesis of the disease and are sometimes the force that drives the disease process. This concept has not been established for autism. In autoimmune diseases, such as systemic lupus erythematosus (SLE), antibodies are found to react with double‐stranded DNA. These antibodies also cross‐react with N‐methyl‐D aspartate receptors. Many SLE patients suffer neurologic syndromes of the central nervous system (CNS). Similarly individuals infected with Group A streptococcus (GAS) have antibodies against the GAS carbohydrate, which cross‐react with tubulin and lysoganglioside GM1 on neurons. During the acute stage of infection, GAS‐infected patients develop Syndenham chorea where the disease process is driven in part by these cross‐reactive antibodies. As the antibody levels decrease, the clinical features of Syndenham chorea resolve. In these two immune‐mediated diseases, antibodies clearly play a role in the pathogenesis of the diseases. There are reports that mothers of individuals with autism have antibodies that react with brain proteins and when these antibodies are passively transferred to pregnant non‐human primates or rodents the offspring has behavioral and nervous system changes. It is still not clear whether the antibodies found in mothers of individuals with autism actually play a role in the disease. More studies need to be performed to identify the proteins recognized by the antibodies and to determine how these could affect development, behavior and changes within the CNS.
Is there a role for routinely screening children with autism spectrum disorder for creatine deficiency syndrome?
Authors: Wang Lv , Angley Manya T. , Sorich Michael J. , Young Robyn L. , McKinnon Ross A. , Gerber Jacobus P.
Published: June 2010

Autism spectrum disorder (ASD) is a complex neurodevelopmental disorder that presents in the first three years of life. Currently, diagnosis of ASD is based on its behavioural manifestations, as laboratory diagnostic tests do not exist. Creatine deficiency syndrome (CDS) is one form of inborn error of metabolism where affected individuals have similar clinical features to individuals with ASD. Abnormal urinary creatine (CR) and guanidinoacetate (GAA) levels have been reported as biomarkers of CDS. We hypothesized that screening for abnormal levels of urinary CR and GAA in children with ASD may assist in identifying a subgroup of ASD individuals who can be managed with dietary interventions. Morning urine samples were collected from children with and without autism and analyzed for CR and GAA levels. Results showed there was no statistically significant difference in urinary CR:creatinine and GAA:creatinine between the children with ASD and sibling or unrelated controls. In conclusion, routine screening for abnormal urinary CR and GAA could be considered in ASD diagnostic protocols; however, individuals positive for CDS are likely to be rare in an ASD cohort.
Neural tube defects induced by folate deficiency in mutant curly tail (Grhl3) embryos are associated with alteration in folate one‐carbon metabolism but are unlikely to result from diminished methylation
Authors: De Castro Sandra C. P. , Leung Kit‐yi , Savery Dawn , Burren Katie , Rozen Rima , Copp Andrew J. , Greene Nicholas D. E.
Published: June 2010

BACKGROUND: Folate one‐carbon metabolism has been implicated as a determinant of susceptibility to neural tube defects (NTDs), owing to the preventive effect of maternal folic acid supplementation and the higher risk associated with markers of diminished folate status. METHODS: Folate one‐carbon metabolism was compared in curly tail (ct/ct) and genetically matched congenic (+ct/+ct) mouse strains using the deoxyuridine suppression test in embryonic fibroblast cells and by quantifying s‐adenosylmethionine (SAM) and s‐adenosylhomocysteine (SAH) in embryos using liquid chromatography tandem mass spectrometry. A possible genetic interaction between curly tail and a null allele of 5,10‐methylenetetrahydrofolate reductase (MTHFR) was investigated by generation of compound mutant embryos. RESULTS: There was no deficit in thymidylate biosynthesis in ct/ct cells, but incorporation of exogenous thymidine was lower than in +ct/+ct cells. In +ct/+ct embryos the SAM/SAH ratio was diminished by dietary folate deficiency and normalized by folic acid or myo‐inositol treatment, in association with prevention of NTDs. In contrast, folate deficiency caused a significant increase in the SAM/SAH ratio in ct/ct embryos. Loss of MTHFR function in curly tail embryos significantly reduced the SAM/SAH ratio but did not cause cranial NTDs or alter the frequency of caudal NTDs. CONCLUSIONS:
Curly tail fibroblasts and embryos, in which Grhl3 expression is reduced, display alterations in one‐carbon metabolism, particularly in the response to folate deficiency, compared to genetically matched congenic controls in which Grhl3 is unaffected. However, unlike folate deficiency, diminished methylation potential appears to be insufficient to cause cranial NTDs in the curly tail strain, nor does it increase the frequency of caudal NTDs. Birth Defects Research (Part A), 2010. © 2010 Wiley‐Liss, Inc.
Segmental isotopic labeling of the Hsp70 molecular chaperone DnaK using expressed protein ligation
Authors: Clerico Eugenia M. , Zhuravleva Anastasia , Smock Robert G. , Gierasch Lila M.
Published: June 2010

Introducing biophysical labels into specific regions of large and dynamic multidomain proteins greatly facilitates mechanistic analysis. Ligation of expressed domains that are labeled in a desired manner before assembly of the intact molecular machine provides such a strategy. We have elaborated an experimental route using expressed protein ligation (EPL) to create an Hsp70 molecular chaperone (the E. coli Hsp70, DnaK) where only one of the two constituent domains was labeled, in this case with NMR active isotopes, allowing visualization of the single domain in the context of the two domain protein. Several technical obstacles were overcome, including choice of site for ligation with retention of function, optimization of ligation yield, and purification from unreacted domains. Ligated semilabeled DnaK was successfully produced with a Cys residue at position 383, and the ligated product harboring the Cys mutation was confirmed to be functional and identical to an expressed Cys‐containing two‐domain construct. The NMR spectrum of the segmentally labeled protein was considerably simplified, enabling unequivocal assignment and enhanced analysis of dynamics, as a prelude to exploring the energy landscape for allostery in the Hsp70 family. © 2010 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 94: 742–752, 2010.

This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
VEGFR1D2 in drug discovery: Expression and molecular characterization
Authors: Di Stasi Rossella , Diana Donatella , Capasso Domenica , Palumbo Rosanna , Romanelli Alessandra , Pedone Carlo , Fattorusso Roberto , D'Andrea Luca D.
Published: June 2010

Vascular endothelial growth factor (VEGF) is a potent angiogenic factor. Its biological activity is mediated by the binding to the extracellular domain of two tyrosine kinase transmembrane receptors: VEGFR1 and VEGFR2. Deletion studies showed that VEGF binding site resides in the first three domains of VEGFR1 and in domains 2 and 3 of VEGFR2. In particular, the second extracellular domain of VEGFR1 (VEGFR1D2) contains most of the VEGF binding requirements. Here, we report an efficient expression protocol and the molecular characterization by spectroscopic techniques of VEGFR1D2. The protein was expressed in E. coli and refolded from inclusion bodies. The recombinant protein assumes the correct fold as assessed by a combination of biochemical and functional assays as well as by NMR characterization. Furthermore, the recombinant VEGFR1D2 was analyzed by circular dichroism and fluorescence spectroscopy. The protein obtained by this procedure is suitable for the structural characterization of the complexes with receptor binders and to be used in interaction/screening studies. © 2010 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 94: 800–809, 2010.

This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
Crystallization of recombinant human growth hormone at elevated pressures: Pressure effects on PEG‐induced volume exclusion interactions
Authors: Crisman Ryan L. , Randolph Theodore W.
Published: June 2010

Crystallization of recombinant human growth hormone (rhGH) at elevated pressures was investigated in the presence of 6,000 molecular weight poly(ethylene glycol; PEG‐6000). Crystallization of rhGH at atmospheric pressure occurred at a protein concentration of 15 mg/mL in 6% PEG‐6000. Crystallization did not occur in the same solutions at 250 MPa. In contrast, at a pressure of 250 MPa in the presence of 8% PEG‐6000, rhGH readily crystallized from solutions containing 35 mg/mL rhGH, whereas amorphous precipitate formed in the same solutions at atmospheric pressure. Osmotic virial coefficients were determined from static light scattering measurements and combined with a hard‐sphere activity coefficient model to predict rhGH activity coefficients as a function of pressure and PEG concentration. Predicted activity coefficients quantitatively matched those determined from equilibrium solubility measurements. The ability to adjust the thermodynamic non‐ideality with pressure provides a valuable tool to study protein crystallization in addition to providing a methodology for obtaining crystals at elevated pressures. Biotechnol. Bioeng. 2010;107:663–672. © 2010 Wiley Periodicals, Inc.
Increasing the activity of monoclonal antibody therapeutics by continuous chromatography (MCSGP)
Authors: Müller‐Späth T. , Krättli M. , Aumann L. , Ströhlein G. , Morbidelli M.
Published: June 2010

The charged monoclonal antibody (mAb) variants of the commercially available therapeutics Avastin®, Herceptin® and Erbitux® were separated by ion‐exchange gradient chromatography in batch and continuous countercurrent mode (MCSGP process). Different stationary phases, buffer conditions and two MCSGP configurations were used in order to demonstrate the broad applicability of MCSGP in the field of charged protein variant separation. Batch chromatography and MCSGP were compared with respect to yield, purity, and productivity. In the case of Herceptin®, also the biological activity of the product stream was taken into account as performance indicator. The robustness of the MCSGP process against feed composition variations was confirmed experimentally and by model simulations. Biotechnol. Bioeng. 2010;107:652–662. © 2010 Wiley Periodicals, Inc.
Germination and inactivation of Bacillus subtilis spores induced by moderate hydrostatic pressure
Authors: Nguyen Thi Minh Hue , Dantigny Philippe , Perrier‐Cornet Jean‐Marie , Gervais Patrick
Published: June 2010

In this study, we investigated the mechanisms of spore inactivation by high pressure at moderate temperatures to optimize the sterilization efficiency of high‐pressure treatments. Bacillus subtilis spores were first subjected to different pressure treatments ranging from 90 to 550 MPa at 40°C, with holding times from 10 min to 4 h. These treatments alone caused slight inactivation, which was related to the pressure‐induced germination of the spores. After these pressures treatments, the sensitivity of these processed spores to heat (80°C/10 min) or to high pressure (350 MPa/40°C/10 min) was tested to determine the pressure‐induced germination rate and the advancement of the spores in the germination process. The subsequent heat or pressure treatments were applied immediately after decompression from the first pressure treatment or after a holding time at atmospheric pressure. As already known, the spore germination is more efficient at low pressure level than at high pressure level. Our results show that this low germination efficiency at high pressure seemed not to be related either to a lower induction or a difference in the induction mechanisms but rather to an inhibition of enzyme activities which are involved in germination process. In fact, high pressure was necessary and very efficient in inducing spore germination. However, it seemed to slow the enzymatic digestion of the cortex, which is required for germinated spores to be inactivated by pressure. Although these results indicate that high‐pressure treatments are more efficient when the two treatments are combined, a small spore population still remained dormant and was not inactivated with any holding time or pressure level. Biotechnol. Bioeng. 2010;107: 876–883. © 2010 Wiley Periodicals, Inc.
Indirect enantioresolution of (R,S)‐mexiletine by reversed‐phase high‐performance liquid chromatography via diastereomerization with [(S,S)‐O,O'‐di‐p‐toluoyl tartaric acid anhydride], (S)‐naproxen and nine chiral reagents synthesized as variants of Marfey's reagent
Authors: Bhushan R. , Tanwar Shivani , Dixit Shuchi
Published: June 2010

Eleven chiral derivatizing reagents (CDRs) were used for preparation of diastereomers of (R,S)‐mexiletine containing a primary amino group in close proximity to the stereogenic center. One anhydride, namely [(S,S)‐O,O'‐di‐p‐toluoyl tartaric acid anhydride] was synthesized and (S)‐naproxen was used as such as the chiral derivatizing reagent. The other nine CDRs were synthesized by substituting one of the fluorine atoms in 1,5‐difluoro‐2,4‐dinitrobenzene with six amino acid amides and three amino acids. The diastereomers were separated by reversed‐phase high‐performance liquid chromatography. The method was validated for linearity, accuracy, limit of detection and limit of quantification. The limit of detection was found in the range of 10–30 pmol. Copyright © 2010 John Wiley & Sons, Ltd.
Synthesis of aminated polysorbate 80 for polyplex‐mediated gene transfection
Authors: Lim Eun‐Kyung , Yang Jaemoon , Suh Jin‐Suck , Huh Yong‐Min , Haam Seungjoo
Published: June 2010

To develop novel gene delivery carriers, aminated polysorbate 80 (P80‐NH2) was synthesized with strong positively charged properties through the introduction of three amine groups. The resulting P80‐NH2 and DNA polyplex exhibited superb condensation abilities due to the high densities of positively charged amines groups. Size and surface charge of polyplex were shown to be well suited for cellular internalization. In addition, the P80‐NH2/DNA polyplex demonstrated acceptable transfection efficiency in HeLa cells and was nontoxic relative to the conventional 25‐kDa polyethyleneimine system. © 2010 American Institute of Chemical Engineers Biotechnol. Prog., 2010
A graphic user interface for evaluation of the camera parameters
Authors: Çakir Mustafa
Published: June 2010

In engineering education/training, virtual modeling and realistic simulation are widely used by instructors due to complexity, cost, and time. There is no universally agreed standard in the current state of robotics for both academic and industrial practice. This forces authors to re‐implement requisite parts. Even for well‐defined approaches, algorithms are being recomposed without any new contribution. Motivated from these concerns and discussions, the virtual tool, MFOCV, is introduced in order to encourage the use of open‐source libraries. Without struggling the complexity, discarding with re‐implementation of admitted methods MFOCV is designed to investigate camera parameters and basic transformation which are the initial steps for the localization and 3D reconstruction. With the utilization of open‐source libraries it is expected that the interests on open architecture will grow and robotics attract more new researchers/groups. MFOCV enables user to observe effects of different camera parameters simultaneously on real images. The presented tool can be used not only for parameter auditing in lectures but also in instrumental localization problems in operative projects. © 2010 Wiley Periodicals, Inc. Comput Appl Eng Educ 21: 147–157, 2013
Cloning and Characterization of the Biosynthetic Gene Cluster of 16‐Membered Macrolide Antibiotic FD‐891: Involvement of a Dual Functional Cytochrome P450 Monooxygenase Catalyzing Epoxidation and Hydroxylation
Authors: Kudo Fumitaka , Motegi Atsushi , Mizoue Kazutoshi , Eguchi Tadashi
Published: June 2010

FD‐891 is a 16‐membered cytotoxic antibiotic macrolide that is especially active against human leukemia such as HL‐60 and Jurkat cells. We identified the FD‐891 biosynthetic (gfs) gene cluster from the producer Streptomyces graminofaciens A‐8890 by using typical modular type I polyketide synthase (PKS) genes as probes. The gfs gene cluster contained five typical modular type I PKS genes (gfsA, B, C, D, and E), a cytochrome P450 gene (gfsF), a methyltransferase gene (gfsG), and a regulator gene (gfsR). The gene organization of PKSs agreed well with the basic polyketide skeleton of FD‐891 including the oxidation states and α‐alkyl substituent determined by the substrate specificities of the acyltransferase (AT) domains. To clarify the involvement of the gfs genes in the FD‐891 biosynthesis, the P450 gfsF gene was inactivated; this resulted in the loss of FD‐891 production. Instead, the gfsF gene‐disrupted mutant accumulated a novel FD‐891 analogue 25‐O‐methyl‐FD‐892, which lacked the epoxide and the hydroxyl group of FD‐891. Furthermore, the recombinant GfsF enzyme coexpressed with putidaredoxin and putidaredoxin reductase converted 25‐O‐methyl‐FD‐892 into FD‐891. In the course of the GfsF reaction, 10‐deoxy‐FD‐891 was isolated as an enzymatic reaction intermediate, which was also converted into FD‐891 by GfsF. Therefore, it was clearly found that the cytochrome P450 GfsF catalyzes epoxidation and hydroxylation in a stepwise manner in the FD‐891 biosynthesis. These results clearly confirmed that the identified gfs genes are responsible for the biosynthesis of FD‐891 in S. graminofaciens.
Single‐Crystalline ZnO Nanowire Bundles: Synthesis, Mechanism and Their Application in Dielectric Composites
Authors: Wang Guangsheng , Deng Yuan , Guo Lin
Published: June 2010

Single‐crystalline ZnO nanowire bundles have been synthesized in large‐scale by an improved microemulsion method in the presence of excessive hydrate hydrazine and dodecyl benzene sulfonic acid sodium salt (DBS) in xylene. The product is characterized using X‐ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and high‐resolution transmission electron microscopy (HRTEM). The result shows that the bundle is composed by many oriented single‐crystalline ZnO nanowires with a length of about 1 μm and a diameter of about 20–30 nm. The influence of DBS, hydrazine and the reaction time on the morphology of final product and the formation mechanism of such nanostructures were discussed; the application in the dielectric composites is also studied.
The trans Influence in the Modulation of Platinum Anticancer Agent Biology: The Effect of Nitrite Leaving Group on Aquation, Reactions with S‐Nucleophiles and DNA Binding of Dinuclear and Trinuclear Compounds
Authors: Montero Eva I. , Zhang Junyong , Moniodis Joseph J. , Berners‐Price Susan J. , Farrell Nicholas P.
Published: June 2010

To examine the effect of leaving group and trans influence on the general reactivity of polynuclear platinum antitumor agents we investigated substitution of the chloride leaving groups with nitrite ion, which forms strong bonds to Pt. It was of interest to explore whether nitrite could be used to modulate biological properties of these agents, in particular the deactivating reactions that occur on reaction with S‐nucleophiles, involving loss of the linking diamine under the trans influence of sulfur. Reported herein is a study of the synthesis, aquation, DNA binding and reactions with glutathione (GSH), methionine (Met) and acetylmethione (AcMet) of nitrito derivatives of di‐ and trinuclear platinum antitumor compounds: [{trans‐PtNO2(NH3)2}2(μ‐NH2(CH2)6NH2)](NO3)2 (1‐NO2) and [{trans‐PtNO2(NH3)2}2(μ‐trans‐Pt(NH3)2{NH2(CH2)6NH2}2)](NO3)4 (1′‐NO2). {1H,15N}‐HSQC NMR studies revealed that 1‐NO2 is inert to aquation reactions, even after prolonged incubation at physiological pH. Monitoring of the interaction of 1‐NO2 with the duplex 5′‐d(ATATGTACATAT)2 (I) showed only unreacted complex, consistent with activation by aquation being a requirement for covalent DNA binding. The reaction of 1‐NO2 with GSH was studied by 1H, 195Pt, 15N and {1H,15N}‐HSQC NMR spectroscopy. For the parent dichlorido compounds (1 and 1′) substitution of chloride by GS− leads to drug degradation involving liberation of the diamine linker. While the same final products trans‐[Pt(SG)2(NH3)2] (5) and trans‐[{Pt(SG)(NH3)2}2‐μ‐SG] (6) are formed, different mechanisms are involved, consistent with the trans influence NO2− > Cl−; the half‐life is slightly longer for 1‐NO2 (1.8 h) compared with 1 (1.3 h). Identification of the intermediate trans‐[Pt(NH3)2(NO2)(SG)] (4) shows that the nitrito group remains coordinated while the linker amine is substituted by coordination of GS−, and then trans labilization of the nitrito group occurs leading to 5 and 6. Reaction of the trinuclear 1′‐NO2 with GSH follows essentially the same reaction pathway. Reaction of 1‐NO2 with Met and AcMet is much slower and only 20 % liberated amine was observed after reaction with Met for 24 h at 37 °C. The final product from reaction with AcMet is trans‐[Pt(NH3)2(NO2)(AcMet)], as in this case coordination of the S‐nucleophile does not lead to trans labilization of the nitrito group.
ChemInform Abstract: Enhanced Reactivity of Tuned Imidazolidin‐2‐one Chiral Auxiliaries in Diels—Alder Reactions.
Authors: ROOS G. H. P. , BALASUBRAMANIAM S.
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Diphenylphosphinooxazoline Ligands with a Chiral Binaphthyl Backbone for Pd‐Catalyzed Allylic Alkylation.
Authors: IMAI Y. , ZHANG W. , KIDA T. , NAKATSUJI Y. , IKEDA I.
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Effect of Phosphorylation on the Reaction Rate of Unnatural Electrophiles with 2‐Keto‐3‐deoxy‐6‐phosphogluconate Aldolase.
Authors: COTTERILL I. C. , SHELTON M. C. , MACHEMER D. E. W. , HENDERSON D. P. , TOONE E . J.
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Zinc Barbier Reaction of Propargyl Halides in Water.
Authors: BIEBER L. W. , DA SILVA M. F. , DA COSTA R. C. , SILVA L. O. S.
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Tandem [4 + 2]/[3 + 2] Cycloadditions with Nitroethylene.
Authors: DENMARK S. E. , HURD A. R.
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: First Example of Samarium Diiodide‐Promoted Sequential Cyclization and Ring‐Expansion Reactions of α‐Bromomethyl Cyclic β‐Keto Esters to Homologated γ‐Keto Esters.
Authors: HASEGAWA E. , KITAZUME T. , SUZUKI K. , TOSAKA E.
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: DTBB‐Catalyzed Lithiation of 3‐Functionalized 1‐Chloropropenes.
Authors: GOMEZ C. , HUERTA F. F. , YUS M.
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Reaction of Thexylalkoxyboranes with Selected Organic Compounds Containing Representative Functional Groups. Comparison of Reducing Characteristics of the Alkoxy Derivatives.
Authors: CHA J. S. , CHANG S. W. , KIM J. M. , KWON O. O. , CHUN J. H. , CHO S. D.
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Phenyltetrafluorotelluromethoxide — A New Oxidative Fluorinating Agent for Olefins.
Authors: LERMONTOV S. A. , BAKHTIN I. V.
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Synthesis of Fluorinated Azulenes.
Authors: MUTHYALA R. S. , LIU R. S. H.
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Using NBS as a Mild Bromination Reagent for Polyalkoxyaromatic Systems.
Authors: BLOOMER J. L. , ZHENG W.
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Condensation of Fluorinated Carbonyl Compounds with Halobenzenes.
Authors: STERLIN S. R. , SHAPOSHNIKOVA E. N. , POSTOVOI S. A. , MYSOV E. I. , ZEIFMAN YU. V.
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Lithium Naphthalenide Induced Reductive Alkylation of α‐Cyano Ketones. A General Method for Regiocontrol of α,α‐Dialkylation of Ketones.
Authors: LIU H.‐J. , ZHU J.‐L. , SHIA K.‐S.
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Reusable Polymer‐Supported Palladium Catalysts: An Alternative to Tetrakis(triphenylphosphine)palladium in the Suzuki Cross‐Coupling Reaction.
Authors: FENGER I. , LE DRIAN C.
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Synthesis of Sterically Hindered Esters via Titanium Catalyzed Transesterification.
Authors: KRASIK P.
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Solid State Acetylation with Acetylimidazole: Selective Protection of Primary Alcohols and Phenols.
Authors: HAGIWARA H. , MOROHASHI K. , SUZUKI T. , ANDO M. , YAMAMOTO I. , KATO M.
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: The Regioselectivity of 1,3‐Disubstituted Allylmetal Species Towards Electrophiles: 1‐(Trimethylsilyl)alk‐2‐enylpotassium Compounds.
Authors: SCHLOSSER M. , FRANZINI L.
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: A Facile Perfluoroallylation of Olefins.
Authors: NGUYEN B. V. , YANG Z.‐Y. , BURTON D. J.
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.