bluuebunny/crossref_metadata_2025_split huggingface dataset:
Large cell/anaplastic medulloblastoma: Outcome according to myc status, histopathological, and clinical risk factors
Authors: von Hoff Katja , Hartmann Wolfgang , von Bueren André Oscar , Gerber Nicolas Ulrich , Grotzer Michael Andreas , Pietsch Torsten , Rutkowski Stefan 
Published: November 2009

AbstractPurposeTo evaluate the prognostic impact of large cell/anaplastic (LC/A) histology together with molecular and clinical risk factors in childhood medulloblastoma.MethodsThree consecutive prospective medulloblastoma trials were screened for patients with the histological diagnosis of LC/A medulloblastoma. Tumors were considered as LC/A if they displayed areas of severe cytological anaplasia or a significant or predominant large cell component. Histology was centrally confirmed. Genomic DNA amplification of c‐myc and n‐myc, and mRNA expression of c‐myc and trkC were analyzed.ResultsTwenty‐eight patients with LC/A medulloblastoma with a median age of 6.1 years (1.4–16.5 years) and a median follow‐up of 4.5 years were identified (5% of all medulloblastoma). Four‐year event‐free (EFS) and overall survival (OS) were 58% and 67%. Young age and metastases (n = 13, 4‐year EFS 31% vs. 82% in 15 children >4 years and without metastases, P = 0.001), large cell histology (n = 9, 4‐year EFS 22% vs. 75%, P = 0.005) and c‐myc amplification (n = 9, 4‐year EFS 22% vs. 89%, P < 0.0001) were negative prognostic factors. C‐myc amplification was highly correlated with young age (P < 0.001), metastases (P = 0.002) and large cell histology (P = 0.007). Outcome of 12 patients with severely anaplastic tumors without these risk factors was not impaired (4‐year EFS 86%).ConclusionIn a subgroup of patients without clinical and molecular risk factors outcome was favorable despite severely anaplastic histology. In contrast, c‐myc amplification and large‐cell histology were associated with an inferior outcome. Intensified treatment strategies should be considered for children with LC/A medulloblastoma and these characteristics. Pediatr Blood Cancer 2010;54:369–376. © 2009 Wiley‐Liss, Inc.
Outcome of chronic idiopathic thrombocytopenic purpura in children
Authors: Bansal Deepak , Bhamare Tanmay Anant , Trehan Amita , Ahluwalia Jasmina , Varma Neelam , Marwaha R.K. 
Published: November 2009

AbstractBackgroundThere is paucity of data on long‐term probability of remission in chronic idiopathic thrombocytopenic purpura (ITP). Aim was to study the course and factors influencing remission of chronic ITP. Chronic ITP was defined as thrombocytopenia persisting >6 months following initial diagnosis.ProceduresCase‐records of children with chronic ITP, aged <14 years, were reviewed in this retrospective study (1987–2006).ResultsTwo hundred seventy children were followed. Median age at diagnosis was 6 years. Median duration of follow up was 30 months (range 6–166). Isolated thrombocytopenia (even if <10 × 109/L) in the absence of “significant” bleeds, by itself was not considered an indication for drug therapy. Sixty‐seven (24.8%) children attained complete remission (CR) over a median period of 18 months (range 7–120). The probabilities of remission at 5 years for males and females were 24% and 39.6%, respectively (P = 0.01). The probability of achieving remission at 10 years in children <8 and ≥8 years was 51.2% and 34%, respectively (P = 0.02). The probability of remission at 5 years for children who received some treatment, versus no treatment was 31.4% and 27%, respectively (P = 0.8). Nine of 18 children, who underwent splenectomy, achieved CR. Intracranial hemorrhage (ICH) occurred in 11 (4%) cases. The time of occurrence of ICH from onset of symptoms varied from 6 to 55 months.ConclusionsThe predicted spontaneous remission rate with chronic ITP was 30% and 44% at 5 and 10 years, respectively. Platelet count at diagnosis and the treatment administered did not influence remission outcomes. Age <8 years and female gender were predictors of a favorable outcome. Pediatr Blood Cancer 2010;54:403–407. © 2009 Wiley‐Liss, Inc.
In vivo monitor oxidative burst induced by Cd2+ stress for the oilseed rape (Brassica napus L.) based on electrochemical microbiosensor
Authors: Xu Qiao , Wei Fang , Wang Zhan , Yang Qin , Zhao Yuan‐Di , Chen Hong 
Published: November 2009

AbstractIntroduction – Since the mechanism of Cd2+ stress for plants is not clear, an in vivo method to monitor Cd2+ stress for plants is necessary. However, oxidative burst (OB) is a signal messenger in the process of Cd2+ stress for plants.Objective – To establish an electrochemical method with poly‐o‐phenylenediamine and Pt microparticle modified Pt electrode (POPD–Pt‐MP–Pt) as a microbiosensor for the in vivo detection of oxidative burst induced by Cd2+ stress in oilseed rape (Brassica napus L.).Methodology – The optimal fabrication of POPD–Pt‐MP–Pt biosensor was achieved. Electrochemical signal was collected by amperometry.Results – After oilseed rape was exposed to 84.9 mM CdCl2 stress, three oxidative bursts were observed in oilseed rape by amperometry at 3.3 h, 8.4 h and 13.2 h, respectively. However, there was no obvious signal observed in the controlled assay.Conclusion – This contribution presents the in vivo monitoring of the OB process induced by Cd2+ stress in oilseed rape by POPD–Pt‐MP–Pt microbiosensor in real‐time. The novel electrochemical microbiosensor not only facilitates the real‐time study in plant self‐defence response to the adverse environment such as Cd2+ stress, but also provides an effective tool for probing the self‐defence mechanism in plants. Copyright © 2009 John Wiley & Sons, Ltd.
The analysis of pyrrolizidine alkaloids in Jacobaea vulgaris; a comparison of extraction and detection methods
Authors: Joosten Lotte , Mulder Patrick P. J. , Vrieling Klaas , van Veen Johannes A. , Klinkhamer Peter G. L. 
Published: November 2009

AbstractIntroduction – Pyrrolizidine alkaloids (PAs) serve an important function in plant defence.Objective – To compare different extraction methods and detection techniques, namely gas chromatography with nitrogen phosphorus detection (GC‐NPD) and liquid chromatography tandem mass spectrometry (LC‐MS/MS) with quadrupole analysers for analysing PAs in Jacobaea vulgaris.Methodology – Both formic acid and sulfuric acid were tested for PA extraction from dry plant material. For GC‐NPD, reduction is required to transform PA N‐oxides into tertiary amines. Zinc and sodium metabisulfite were compared as reducing agents.Results – The lowest PA concentration measured with GC‐NPD was approximately 0.03 mg/g and with LC‐MS/MS 0.002 mg/g. The detection of major PAs by both techniques was comparable but a number of minor PAs were not detected by GC‐NPD. With the LC‐MS/MS procedure higher concentrations were found in plant extracts, indicating that losses may have occurred during the sample preparation for the GC‐NPD method. Zinc proved a more effective reducing agent than sodium metabisulfite. The sample preparation for LC‐MS/MS analysis using formic acid extraction without any reduction and purification steps is far less complex and less time consuming compared to GC‐NPD analysis with sulfuric acid extraction and PA N‐oxide reduction with zinc and purification.Conclusions – In terms of sensitivity and discrimination, formic acid extraction in combination with LC‐MS/MS detection is the method of choice for analysing PAs (both free and N‐oxides forms) in plant material. Copyright © 2009 John Wiley & Sons, Ltd.
The effect of montmorillonite and compatibilizer quantities on stiffness and toughness of polyamide nanoblends
Authors: Gallego R , García‐López D , Merino JC , Pastor JM 
Published: November 2009

AbstractAlthough polymer blend nanocomposites are widely studied, the balance between stiffness and toughness has not yet been investigated in detail. Some materials producers as well as some sectors in the automotive industry try to improve the toughness of materials without an important loss in stiffness. With this in mind, the aim of the study reported here was to obtain a good balance between toughness and stiffness of polymer blends with different amounts of clay and compatibilizer. In this context, the microstructure of polyamide 6/ethylene–propylene–diene metallocene terpolymer/(ethylene–propylene–diene copolymer)‐graft‐(maleic anhydride) blends with various amounts of clay (2, 3, 4 and 5 wt%) and compatibilizer (10 and 20 wt%) was studied to analyse the achieved morphology to understand the macroscopic properties. The morphology of the rubber phase and the dispersion of the montmorillonite (MMT) are the main factors that influence the mechanical properties. In this sense, the highest Young's modulus is achieved for nanoblends with 5 wt% of MMT, although this nanoblend has the lowest value of notched Izod impact strength. The results obtained suggest that there is a clear trade‐off between stiffness, toughness and temperature behaviour when the ratio of (ethylene–propylene–diene copolymer)‐graft‐(maleic anhydride) to MMT is 5:1. Copyright © 2009 Society of Chemical Industry
Interactions between polymer‐grafted particles and bare particles for biocompatibility applications
Authors: Trombly David , Ganesan Venkat 
Published: November 2009

AbstractWe use self‐consistent field theory (SCFT) to study the interactions between a polymer‐grafted spherical particle and a bare spherical particle and explore how these interaction energies depend on the radii of the two particles and the grafting density. We find that the magnitude of the interaction energies increases with the radii of both the grafted and bare particles and with increasing grafting density. We also find a universal scaling law for the interaction potential which exhibits a power‐law dependence on both particle sizes, a linear dependence on grafting density, and a logarithmic dependence on interparticle distance with a range of interaction that scales with brush height. We compare our numerical results to those obtained using the Derjaguin approximation. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 2566–2577, 2009
Common variants at 8q24 are associated with prostate cancer risk in Taiwanese men
Authors: Chen Marcelo , Huang Yu‐Chuen , Yang Stone , Hsu Jong‐Ming , Chang Yen‐Hwa , Huang William Ji‐Shian , Chen Yi‐Ming Arthur 
Published: November 2009

AbstractBACKGROUNDRecently, independent genome‐wide scans have found multiple genetic variants at 8q24 to be associated with prostate cancer risk. This study was performed to determine whether two of the variants more strongly associated with prostate cancer risk in European and American populations, specifically rs16901979 and rs6983561, were also associated with prostate cancer risk in Taiwanese men.METHODSWe conducted a case–control study comprising of 340 prostate patients and 336 healthy controls. Genotyping was performed for rs16901979 and rs6983561. Their association with disease stage, tumor grade, PSA level and disease aggressiveness was also determined.RESULTSThe risk allele A of rs16901979 was associated with a 1.28‐fold increase in prostate cancer risk (P = 0.046), and the risk allele C of rs6983561 was associated with a 1.40‐fold increase in prostate cancer risk (P = 0.006). When compared with controls, the risk allele of rs6983561 was more frequent in patients with more aggressive disease. Analysis of the cumulative risk of rs1447295, a confirmed risk variant, and one of these markers showed that compared to men who do not have any of these risk variants, men who carry any combination of 1 or 2 risk genotypes have a gradually increased prostate cancer risk (P for trend <0.001).CONCLUSIONThe variants rs16901979 and rs6983561 at 8q24 are associated with prostate cancer risk in Taiwanese men. Prostate 70: 502–507, 2010. © 2009 Wiley‐Liss, Inc.
Insecticide resistance traits differ among and within host races in Aphis gossypii
Authors: Carletto Jérôme , Martin Thibaud , Vanlerberghe‐Masutti Flavie , Brévault Thierry 
Published: November 2009

AbstractBACKGROUND: The polyphagous cotton‐melon aphid Aphis gossypii Glover is structured into geographically widespread host races comprising a few clones specialised on Cucurbitaceae, cotton, eggplant or pepper. To assess insecticide resistance among and within host races, leaf disc bioassays were conducted on aphid clones collected from Cucurbitaceae (genotypes C4 and C9), cotton (genotypes Burk and Ivo), eggplant (genotype Auber) and pepper (genotype PsP4). Molecular diagnostic (PCR‐RFLP) and enzyme assays were also performed to detect the basic mechanisms underlying insecticide resistance.RESULTS: All six clones were susceptible to acetamiprid (neonicotinoid) or carbosulfan (carbamate). Conversely, all clones were resistant to dimethoate (organophosphate) (RF = 4.1–38.1) and carried mutation S431F in the acetylcholinesterase gene. Auber, PsP4 and Burk also carried mutation A302S in this gene, which possibly conferred moderate resistance (RF = 3.7–6.8) to profenofos and monocrotophos (organophosphates). Auber and Burk were highly resistant (RF = 41.2 and 473 respectively) to cypermethrin (pyrethroid). This resistance was likely associated with point mutation super‐kdr (M918L) in the voltage‐gated sodium channel gene (para gene) or metabolic detoxification mediated by esterase and oxidase enzymes.CONCLUSION: Multiple resistance to a broad range of insecticides and multiple mechanisms of resistance in some clones could explain to some extent the low genetic diversity observed within A. gossypii host races. Copyright © 2009 Society of Chemical Industry
Identification of a novel antitumor peptide based on the screening of an Ala‐library derived from the LALF32–51 region
Authors: Vallespi Maribel G. , Fernandez Julio R. , Torrens Isis , Garcia Isbel , Garay Hilda , Mendoza Osmani , Granadillo Milaid , Falcon Viviana , Acevedo Boris , Ubieta Raimundo , Guillen Gerardo E. , Reyes Osvaldo 
Published: November 2009

AbstractNovel therapeutic peptides are increasingly making their way into clinical application. The cationic and amphipathic properties of certain peptides allow them to cross biological membranes in a non‐disruptive way without apparent toxicity increasing drug bioavailability. By modifying the primary structure of the Limulus‐derived LALF32–51 peptide we designed a novel peptide, L‐2, with antineoplastic effect and cell‐penetrating capacity. Interestingly, L‐2 induced cellular cytotoxicity in a variety of tumor cell lines and systemic injection into immunocompetent and nude mice bearing established solid tumor, resulted in substantial regression of the tumor mass and apoptosis. To isolate the gene transcripts specifically regulated by L‐2 in tumor cells, we conducted suppressive subtractive hybridization (SSH) analysis and identified a set of genes involved in biological processes relevant to cancer biology. Our findings describe a novel peptide that modifies the gene expression of the tumor cells and exhibits antitumor effect in vivo, indicating that peptide L‐2 is a potential candidate for anticancer therapy. Copyright © 2009 European Peptide Society and John Wiley & Sons, Ltd.
Structure‐antigenicity of the V3 region of SIVmac envelope glycoprotein
Authors: Gaston Fabrice , Babas Tahar , Lakhdar‐Ghazal Faouzi , Bahraoui Elmostafa 
Published: November 2009

AbstractThe objective of this study was to analyze the immunogenicity and antigenicity of the V3 domain (Cys313–Cys346) of the external envelope glycoprotein gp125 of SIVmac251. The corresponding peptide was synthesized and characterized as linear and cyclic peptides. Our results showed that this region, as for HIV‐1, contained an immunodominant epitope. The antigenicity was similar for the linear and cyclic peptides when tested against a panel of 15 sera from SIV infected macaques. Similarly, both peptide structures presented similar immunogenicity as shown by the characterization of the anti‐peptide antibodies produced in rabbits against the cyclic and linear forms. But, unexpectedly, the antibodies produced against linear peptides recognized with a relatively higher intensity the native envelope gp140 than those produced against the cyclic structure. Furthermore, we showed that these antibodies recognized better the deglycosylated form of the glycoprotein. But, in contrast to the neutralizing activity obtained with anti‐V3 peptides from HIV‐1, no antiviral activity was obtained with antibodies generated against linear or cyclic SIVmac V3 peptides. Copyright © 2009 European Peptide Society and John Wiley & Sons, Ltd.
Preparation of 13C single‐walled carbon nanotubes by pulsed laser vaporization
Authors: Stürzl Ninette , Lebedkin Sergei , Malik Sharali , Kappes Manfred M. 
Published: November 2009

AbstractWe describe a facile procedure to obtain 13C single‐walled carbon nanotubes (SWNTs) in gram quantities. The procedure is based on sintering to obtain 13C graphitic targets from commercially available amorphous 13C‐powder doped with nickel and cobalt metals. The targets are robust enough to be used for the synthesis of SWNTs by pulsed laser vaporization (PLV). This method provides a high degree of conversion of the initial carbon material into nanotubes. Raman and photoluminescence (PL) spectra of the resulting 13C nanotubes are presented.
In vitro effects of SWCNT: Role of treatment duration
Authors: Bruinink Arie , Manser Pius , Hasler Sabrina 
Published: November 2009

AbstractDespite the growing interest in single carbon nanotubes (SWCNT) for consumer products still little is known about their toxic potential and toxicomechanism. The present study was performed to elucidate the role of treatment duration and catalyst contamination in SWCNT induced effects. For this SWCNT of two different purities were evaluated: SWCNT raw material (SWCNTrm) and purified SWCNT (SWCNTpur). Our data suggest that the presence of an increased quantity of SWCNT contaminants has a negative impact on lung epithelial A549 cell functionality. Evidence was found that the cellular effects of SWCNTpur are based on accumulation within the target compartment of the cell. In case of SWCNTrm adaptations of the cell to the SWCNT exposure may occur reducing the importance of accumulation regarding the observed effects.
Using line group theory for the symmetry assignment of the phonons of single walled carbon nanotubes
Authors: Rusznyák Ádám , Koltai János , Zólyomi Viktor , Kürti Jenő 
Published: November 2009

AbstractCalculating the phonon dispersions of an arbitrary single walled carbon nanotube became cheap in the numerical sense by exploiting the screw axis symmetry. The eigenvectors of the dynamical matrix are the irreducible basis vectors of the representation of the symmetry group of the nanotubes: L(2n)n/mcm for achiral and Lqp22 for chiral tubes. We developed a numerical code which can solve the eigenvalue problem of the dynamical matrix produced by a density functional theory code (VASP), in the helical Brillouin zone. The code represents the symmetry elements of the line group in the helical unit cell. After decomposing the matrix representation we obtain one to one correspondence between the vibrational modes and the irreducible representations of the line group. Thus we obtain first principles level phonon dispersions accompanied by a full line group based symmetry assignment for all the phonon branches.
Raman response of FeCl3 intercalated single‐wall carbon nanotubes at high doping
Authors: De Blauwe Katrien , Kramberger Christian , Plank Wolfgang , Kataura Hiromichi , Pichler Thomas 
Published: November 2009

AbstractA detailed study on the photoselective Raman response of p‐type intercalated single‐wall carbon nanotube (SWCNT) is presented. Here, we focus on the high doping region. The shift of the G‐line is used to monitor the doping level of the p‐type intercalated SWCNT using irontrichloride. Special emphasis is given on the changes in the dispersion of the D‐ and G′‐lines as a function of doping. For very high doping levels a decrease of the slope is observed.
Polarised Raman measurements on the core complex of crystallised photosystem II
Authors: Brose Katharina , Zouni Athina , Broser Matthias , Müh Frank , Maultzsch Janina 
Published: November 2009

AbstractIn photosynthesis the sunlight is collected by antenna pigments and transmitted to special molecule structures called photosystem I (PS I) and photosystem II (PS II), where the energy of light is transformed into a separation of charge. In the PS II reaction centre (RC), there are two β‐carotene molecules CarD1 and CarD2, which are oriented perpendicular to each other. The role of these molecules in the photosynthesis process is still unknown. We use Raman spectroscopy to study the two β‐carotenes. We present polarised Raman measurements of the β‐carotene vibrational modes in single crystals of photosystem II (PS II) and discuss the possible origin of the observed polarisation dependence. These measurements are important for the basic understanding of the β‐carotene vibrational properties and guide future investigations of PS II.
An approach that can quickly assess product reliability
Authors: Zanoff J. , Ekwaro‐Osire S. 
Published: November 2009

AbstractOne of the ways to determine the inherent reliability of a design is to test it under controlled environments based on the product usage that is understood by the development requirements. This can be accomplished by performing a reliability growth test on the product. A testing approach can be developed that enhances the product reliability and reduces the production testing cycle. Research performed to date points to the fact that this proposed methodology may not exist, and is the focus of continued research to refine the development of an approach to fill this gap. The combining of multiple testing approaches in order to ensure that the reliability requirement is met or exceeded while at the same time having the capability to reduce the testing cycle time when required due to schedule and cost constraints has not been addressed in the open literature till date. The methodology is to utilize a combination of multiple testing approaches to accomplish this task by exploring complementary testing ideas from various technologies that have been utilized previously with documented success. This approach demonstrated that component‐level testing reduced the product‐level failures by greater than 80% while at the same time reducing the schedule to complete all testing. Copyright © 2009 John Wiley & Sons, Ltd.
Removal of nitrite with sulfamic acid for nitrate N and O isotope analysis with the denitrifier method
Authors: Granger Julie , Sigman Daniel M. 
Published: November 2009

AbstractIn environmental water samples that contain both nitrate (NO) and nitrite (NO), isotopic analysis of nitrate alone by all currently available methods requires pretreatment to remove nitrite. Sulfamic acid addition, used previously for this purpose (Wu JP, Calvert SE, Wong CS. Deep‐Sea Research Part I – Oceanographic Research Papers 1997; 44: 287), is shown here to be compatible with the denitrifier method for both N and O isotope analysis of nitrate. Sulfamic acid at a pH of ∼1.7 reduces nitrite to N2. Samples are then neutralized with base prior to isotope analysis, to alleviate the buffering demands of the bacterial media and as a precaution to prevent modification of nitrate during storage with the residual sulfamic acid at low pH. Under appropriate reaction conditions, nitrite is completely removed within minutes. Sulfamic acid treatment does not compromise the completeness of the conversion of nitrate into N2O or the precision and accuracy of N and O isotope measurements by the denitrifier method. Nitrite concentrations upwards of 7 times the ambient nitrate can be removed without affecting the isotope composition of nitrate. The method is applied to analyses of the coupled N and O isotopes of nitrate and nitrite in waters of the Mexican Margin, to illustrate its efficacy and utility when employed either in the field upon sample collection or in the lab after months of frozen sample storage. Copyright © 2009 John Wiley & Sons, Ltd.