bluuebunny/crossref_metadata_2025_split huggingface dataset:
Spectrum and presentation of pediatric malignancies in the HIV era: Experience from Blantyre, Malawi, 1998–2003
Authors: Sinfield R.L. , Molyneux E.M. , Banda K. , Borgstein E. , Broadhead R. , Hesseling P. , Newton R. , Casabonne D. , Mkandawire N. , Nkume H. , Hodgson T. , Liomba G. 
Published: June 2006

AbstractBackgroundData on childhood cancers in Africa are sparse, particularly since the spread of HIV. We aimed to document the frequency of pediatric cancers presenting to a large central hospital in Malawi, detailing the presenting features, initial investigations, and HIV status of these children.ProcedureA retrospective audit of the spectrum and clinical presentation of cancers among children (<16 years) seen at Queen Elizabeth's Central Hospital (QECH), between 1998 and 2003.ResultsSeven hundred seven children with cancer were seen, the number of cases per year increased over the time period; 50% (351) had Burkitt lymphoma, 13% (89) had retinoblastoma, and 9% (61) had Kaposi sarcoma, with a variety of other tumors comprising the remainder. Kaposi sarcoma markedly increased in frequency over time. Histological verification of diagnosis was available for 49% (348). The proportion of children with cancer who were tested for HIV increased over time, but varied by cancer type. Amongst those tested, the seroprevalence was 93% (52/56) for children with Kaposi sarcoma, 4% (11/289) for those with Burkitt lymphoma, 31% (8/26) for those with other non‐Hodgkin lymphomas, 7% (1/15) for those with Hodgkin disease, and 5% (5/103) for those with other cancers.ConclusionsThe number of cases seen per year has increased over the study period for almost all cancers, but in particular for Kaposi sarcoma. Burkitt lymphoma remains the commonest pediatric tumor in Malawi. In the case of Burkitt lymphoma, non‐Hodgkin lymphoma, and Kaposi sarcoma there is a significant difference in the presentation of HIV‐seropositive and ‐seronegative children. Pediatr Blood Cancer 2007;48:515–520. © 2006 Wiley‐Liss, Inc.
Renin‐induced hypertension in Wilms tumor patients
Authors: Maas M.H. , Cransberg K. , van Grotel M. , Pieters R. , van den Heuvel‐Eibrink M.M. 
Published: June 2006

AbstractBackgroundSince the report that hypertension associated with Wilms tumor (WT) may be renin‐induced, no larger series than 13 patients have been published. Nevertheless, angiotensin converting enzyme (ACE) inhibitors have become treatment of choice for hypertension in WT patients. The purpose of this study was to investigate the correlation between plasma renin levels and blood pressure in a larger cohort of WT patients.ProcedureIn this retrospective, single‐center study, data on blood pressure and plasma renin were analyzed in 86 WT patients treated according to the consecutive SIOP protocols 6, 9, 93‐01, and 2001.ResultsAt diagnosis, 47 WT patients suffered from hypertension (55%). In 31 of these patients plasma renin levels were analyzed; increased plasma renin levels were found in 25/31 patients (81%). In contrast, normal plasma renin levels were measured in 8/13 of the patients with a normal blood pressure (P = 0.012). Twenty‐eight children received antihypertensive treatment before surgery, in 25 of them blood pressure normalized before surgery. Blood pressure was normal directly after surgery in all patients but 4, in whom blood pressure recovered to normal within a few weeks.ConclusionsThis retrospective study shows that hypertension in WT patients is associated with elevated plasma renin levels, indicating that ACE inhibitors may be a good therapeutic option in at least a subset of WT patients with hypertension before nephrectomy. Pediatr Blood Cancer 2007;48:500–503. © 2006 Wiley‐Liss, Inc.
Vaccines, antibiotics, and atopy
Authors: Mullooly John P. , Schuler Roberleigh , Barrett Michael , Maher Julie E. 
Published: June 2006

AbstractPurposeEarly exposure to vaccines and antibiotics may increase the risk of developing atopy by protecting against infectious agents and reducing duration and severity of infections (the hygiene hypothesis). It may also shift the developing immune system towards a more allergic response. We assess possible associations in young allergy clinic patients.MethodsWe conducted a case‐control study of 6‐ to 16‐year‐old new allergy clinic patients who were skin tested for inhalant allergens during 1987–2001 and enrolled in KPNW since birth (n = 1074). Atopic cases had positive tests for at least one inhalant allergen. Non‐atopic controls had negative tests for all inhalant allergens. Using logistic regression analysis, we estimated atopy odds ratios for vaccine and antibiotic exposure variables and associations between vaccine and antibiotic exposures during the first 2 years of life and subsequent new allergy diagnoses.ResultsAtopy was not significantly associated with numbers of vaccine and antigen doses, or number of different antigens during the first 2 years of life. Number of antibiotic prescriptions was negatively associated with atopy risk. Neither exposure was significantly associated with risk of new allergy diagnoses in atopic children.ConclusionsAtopy development appears to be unrelated to early vaccine exposure. Frequency of antibiotic prescriptions during early life, a proxy for infection frequency, appears to protect against allergic sensitization. Neither vaccines nor antibiotics appear to induce subsequent allergic reactions in atopic children. Copyright © 2006 John Wiley & Sons Ltd.
Radiation‐induced dispersion polymerization of methyl methacrylate using waterborne polyurethane as stabilizer
Authors: Zhang Guixi , Zou Mingxuan , Wang Shijie , Zhang Zhicheng 
Published: June 2006

AbstractWaterborne polyurethane (WPU) without vinyl groups was synthesized and used as a stabilizer to prepare poly(methyl methacrylate) (PMMA) particles via dispersion polymerization with γ‐rays. The WPU molecular structure was characterized by Fourier transform infrared spectroscopy and 1H NMR. PMMA particles were observed using scanning electron microscopy. The grafting reaction between PMMA and WPU was ascertained using 1H NMR. Copyright © 2006 Society of Chemical Industry
Effect of coupling agents on the thermal and mechanical properties of polypropylene–jute fabric composites
Authors: Acha Betiana A , Reboredo María M , Marcovich Norma E 
Published: June 2006

AbstractComposites with different jute fabric contents and polypropylene (PP) were prepared by compression molding. The composite tensile modulus increased as the fiber content increased, although the strain at break decreased due to the restriction imposed on the deformation of the matrix by the rigid fibers. Moreover, and despite the chemical incompatibility between the polar fiber and the PP matrix, the tensile strength increased with jute content because of the use of long woven fibers. The interfacial adhesion between jute and PP was improved by the addition of different commercial maleated polypropylenes to the neat PP matrix. The effect of these coupling agents on the interface properties was inferred from the resulting composite mechanical properties. Out‐of‐plane instrumented falling weight impact tests showed that compatibilized composites had lower propagation energy than uncompatibilized ones, which was a clear indication that the adhesion between matrix and fibers was better in the former case since fewer mechanisms of energy propagation were activated. These results are in agreement with those found in tensile tests, inasmuch as the compatibilized composites exhibit the highest tensile strength. Scanning electron microscopy also revealed that the compatibilized composites exhibited less fiber pullout and smoother fiber surface than uncompatibilized ones. The thermal behavior of PP–compatibilizer blends was also analyzed using differential scanning calorimetry, to confirm that the improvements in the mechanical properties were the result of the improved adhesion between both faces and not due to changes in the crystallinity of the matrix. Copyright © 2006 Society of Chemical Industry
Preparation of nano‐sized poly(ethylene oxide) star microgels via reversible addition‐fragmentation transfer polymerization in selective solvents
Authors: Zheng Quan , Zheng Gen‐hua , Pan Cai‐yuan 
Published: June 2006

AbstractPoly(ethylene oxide) (PEO) star microgels with a cross‐linked polystyrene core were successfully prepared by reversible addition‐fragmentation transfer polymerization of styrene (St) and divinylbenzene (DVB) with dithiobenzoate‐terminated PEO monomethyl ether (DTB‐MPEO) as macro chain transfer agent in mixtures of ethanol and tetrahydrofuran (THF). The formation of star polymers was affected by polymerization time, solvents and St:DVB:DTB‐MPEO molar ratios. Narrow polydispersed star microgels with high molecular weight were obtained under appropriate polymerization conditions. Transmission electron micrographs suggest that PEO star polymers could form nano‐size spherical micelles in mixtures of water and THF, which further demonstrates the amphiphilic nature of the star polymers. Copyright © 2006 Society of Chemical Industry
Role of ionic interactions in the compatibility of polyester ionomers with poly(ethylene terephthalate) and nylon 6
Authors: Iyer Subramanian , Schiraldi David A. 
Published: June 2006

AbstractWater absorption and other properties of polyamides can potentially be modified by blending with polyesters. The compatibility of a polyester ionomer melt‐blended with nylon‐6 is studied in this article, examining the effect of blending upon crystallization behaviors, morphology, thermal/mechanical properties, and water absorption. Comparisons of the crystallization behaviors of the ionomer/nylon‐6 blends with poly(ethylene terephthalate)/nylon‐6 blends suggest increased compatibility due to greater interactions between the two phases. The results indicate that the presence of a significant amount of the ionomeric groups is required to improve polyester compatibility with polyamides. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 2091–2103, 2006
Solution properties of NR/PU block copolymers by size‐exclusion chromatography and viscometry
Authors: Gopakumar S. , Gopinathan Nair M. R. 
Published: June 2006

AbstractSoluble block copolymers based on natural rubber and polyurethane oligomers derived from 1,3 butane diol and toluene diisocyanate were synthesized for the first time. The dilute solution properties of these block copolymers dissolved in tetrahydrofuran (THF) were studied by viscometry and gel permeation chromatography (GPC). The Mark–Houwink constants K and a of the block copolymer system were determined by the molecular weight data from GPC combined with the viscosity data. Both the values were found to be in the range usually given by flexible elastomers. The intrinsic viscosity values were found to decrease successively with a decrease in the NCO/OH ratio from 1.12 to 1.05. The unperturbed chain parameters, Kθ and B were determined from the viscosity data. The Kθ calculated was used to get the unperturbed end‐to‐end distance and radius of gyration of the block copolymer systems in THF. The viscosity data were also used to study the chain conformation in dilute solutions. It was found that the molecules adopt a compressed core and shell conformation in which the higher molecular weight component, NR, forms the shell, which compresses the PU core. All the block copolymers assume a compressed segregated core and shell model which changes to a partially segregated core and shell conformation, or partially Gaussian conformation, at the transition temperature located at 70 °C. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 2104–2111, 2006
Application of Two‐Dimensional Detectors in X‐ray Diffraction Materials Structure Analysis
Authors: Fiala Jaroslav , Kolega Michal 
Published: June 2006

AbstractThe examination of the azimuthal (lateral) diffraction line profile, i.e., the size, number and shape of individual diffraction spots of which discontinuous diffraction line consist, often reveals useful information on the material's structure which cannot be obtained by the application of other analytical techniques. The information obtained can be advantageously used in the development and optimization of technological processes as well as for monitoring of processes which degrade the material's structure during their use.
In‐situ Investigation during Tempering of a High Speed Steel with X‐ray Diffraction
Authors: Wießner Manfred , Kleber Siegfried , Kulmburg Alfred 
Published: June 2006

AbstractThe combined use of a X‐ray diffractometer and a high temperature chamber allows in‐situ determination of microstructure during heat treatment. X‐ray diffractograms are recorded during tempering of high speed steels. The Rietveld method is used in connection with size‐strain analysis. Lattice parameters of austenite and martensite are utilized for estimating the change of carbon content that has massive influence on the secondary hardening. Nevertheless, it was shown that the heat treatment of deep‐frozen high speed steel cannot be deduced a priori from the applied tempering process under conventional quenching conditions. The differently conditioned microstructures are based on different phase amounts and microstrain‐situations.
Real‐time XRD Investigations During the Formation of Cu(IngGa)Se2 Thin Films
Authors: Hergert Frank , Jost Stefan , Hock Rainer , Purwins Michael 
Published: June 2006

AbstractKnowledge of the solid‐state reactions providing the synthesis of the absorber material Cu(IngGa)Se2 well below its melting point is an essential prerequisite for the further optimization of the technologically relevant production processes. Therefore, powder XRD has been applied as nondestructive tool to follow chemical solide‐state reactions in‐situ. Subsequent Rietveld refinement provides the quantitative phase evolution time.
Temperature Resolved X‐ray Diffraction for the Investigation of the Phase Transitions of FOX‐7
Authors: Kempa P. B. , Herrmann M. 
Published: June 2006

AbstractThe phase behavior of 1,1‐Diamino‐2,2‐dinitroethylene (FOX‐7) was investigated by means of temperature resolved X‐ray powder diffraction. Three phases were observed, and α‐ and β‐FOX‐7 were identified by X‐ray diffraction. The following transition scheme was found:Heating: α → β → γ at 113 °C (α→β) and 173 °C (β→γ)Cooling: α (+γ) ← γ between 50 and 75 °CThe α/β‐transition is completely reversible, and the γ/α‐transition on cooling revealed to be incomplete. A fourth phase which is described in literature was not found.
Observation and Characterization of Structural Phase Transitions by X‐Ray Powder Diffraction
Authors: Depmeier Wulf 
Published: June 2006

AbstractSome of the basic properties of powder diffraction are summarized after a short introduction into the theory. Then it is described phenomenologically how various kinds of structural transformations affect the powder diffraction pattern. This is achieved on emphasizing that diffraction studies on powders are statistically more sound than those on single crystals, thus allowing the reliable determination of the generic properties of a given crystal structure.
Toxicity of indoxacarb and spinosad to the multicolored Asian lady beetle, Harmonia axyridis (Coleoptera: Coccinellidae), via three routes of exposure
Authors: Galvan Tederson L , Koch Robert L , Hutchison William D 
Published: June 2006

AbstractThe use of selective insecticides may improve conservation of natural enemies and therefore contribute to the success of integrated pest management (IPM) programs. In this study, the toxicity of two commonly used selective insecticides, indoxacarb and spinosad, to the multicolored Asian lady beetle, Harmonia axyridis (Pallas), was evaluated. Third instars and adults of H. axyridis were exposed to indoxacarb at 50 and 100% of the field rate (FR), to spinosad at 100% FR and to water (untreated check) under laboratory conditions via three routes of exposure. Treatments were applied directly on insects (i.e., topical application), on Petri dishes (i.e., residues), or on soybean aphids, Aphis glycines Matsumara (i.e., treated prey). Mortality of exposed individuals in each life stage was recorded 2 and 7 days after treatment. Logistic regression indicated that indoxacarb at 100% FR, followed by indoxacarb at 50% FR, was more insecticidal than spinosad to third instars. Mortality was higher when H. axyridis were exposed to both insecticides via residues followed by treated prey. Indoxacarb at 100 or 50% FR was insecticidal to adults. Adults were tolerant to spinosad via all routes of exposure. The present results suggest that indoxacarb may decrease H. axyridis field populations by causing mortality to larvae and adults via all routes of exposure. Implications of the toxicity of indoxacarb to H. axyridis within an IPM context and possible reasons for the differences in susceptibility of H. axyridis for each route of exposure are discussed. Copyright © 2006 Society of Chemical Industry
Antifeedant and toxicity effects of thiophenes from four Echinops species against the Formosan subterranean termite, Coptotermes formosanus
Authors: Fokialakis Nikolas , Osbrink Weste LA , Mamonov Leonid K , Gemejieva Nadejda G , Mims Amelia B , Skaltsounis Alexios L , Lax Alan R , Cantrell Charles L 
Published: June 2006

AbstractOver 220 crude extracts from repositories generated from plants native to Greece and Kazakhstan were evaluated for termiticidal activity against the Formosan subterranean termite, Coptotermes formosanus Shiraki (Isoptera: Rhinotermitidae). Emerging from this screening effort were bioactive extracts from two Greek species (Echinops ritro L. and Echinops spinosissimus Turra subsp. spinosissimus) and extracts from two Kazakhstan species (Echinops albicaulis Kar. & Kir. and Echinops transiliensis Golosh.). Fractionation and isolation of constituents from the most active extracts from each of the four species has been completed, resulting in the isolation of eight thiophenes possessing varying degrees of termiticidal activity. 2,2′:5′,2”‐Terthiophene and 5′‐(3‐buten‐1‐ynyl)‐2,2′‐bithiophene demonstrated 100% mortality against C. formosanus within 9 days at 1 and 2 wt% concentrations respectively. In addition, all but two of the eight compounds tested were significantly different from the solvent controls in the filter paper consumption bioassay. Copyright © 2006 Society of Chemical Industry
Resistance of avocado thrips (Thysanoptera: Thripidae) to sabadilla, a botanically derived bait
Authors: Humeres Eduardo C , Morse Joseph G 
Published: June 2006

AbstractBioassays were conducted on four avocado thrips (Scirtothrips perseae Nakahara) populations in southern California that had had limited past exposure to the botanical pesticide sabadilla, with the objective of establishing baseline susceptibility levels for the purpose of resistance monitoring. Reports of avocado thrips resistance in a grove that had received six sabadilla sprays over 2 years were confirmed when a bioassay indicated resistance ratios of 7.6 and 18.8 at the LC50 and LC90, respectively. Owing to the availability of other unrelated pesticides, sabadilla sprays were discontinued at this site, and, after 5.5 years, resistance ratios had dropped to near baseline levels. Avocado thrips baseline susceptibility to cyfluthrin was also obtained from one grove for future resistance monitoring studies. Resistance management principles are discussed in relation to the limited future options available for avocado thrips control. Copyright © 2006 Society of Chemical Industry
Molecular dynamics simulations of a set of isoniazid derivatives bound to InhA, the enoyl‐acp reductase from M. tuberculosis
Authors: Pasqualoto Kerly F. M. , Ferreira Márcia M. C. , Santos‐Filho Osvaldo A. , Hopfinger Anton J. 
Published: June 2006

AbstractLigand‐receptor molecular dynamics simulations (MDS) were carried out for a set of hydrazides bound to the enoyl‐acp reductase from M. tuberculosis, InhA (PDB entry code 1zid). The hypothesized active conformations resulting from a previous receptor‐independent (RI) 4D‐QSAR analysis and related optimum model/alignment were used in this study. The molecular dynamics simulations (MDS) protocol employed 500000 steps for each ligand‐receptor complex, the step size was 0.001 ps (1 fs), and the simulation temperature was 310 K, the same temperature used in the biological assay. An output trajectory file was saved every 20 simulation steps, resulting in 25,000 conformations. The hydration shell model was used to calculate the solvation energy of the lowest‐energy conformation obtained from each MDS. Structural parameters as well as binding energy contributions were considered in this analysis. The thermodynamic descriptors ELE1,4, ELtors, ELvdW, ELel, and ELel+Hb appear to be more relevant to the biological activity. These findings can be meaningful for developing QSAR studies and for designing new antituberculosis agents. © 2006 Wiley Periodicals, Inc. Int J Quantum Chem, 2006
MRCI study of the photoelectron spectrum of GeC and GeSi and their GeC+ and GeSi+ ions
Authors: Ueno Leonardo T. , Marim L. R. , Dal Pino Jr. A. , Machado Francisco B. C. 
Published: June 2006

AbstractThe lowest‐lying states of the species GeC, GeC+, GeSi, and GeSi+ were studied using the multireference configuration interaction (MRCI) method and the aug‐cc‐pVQZ basis set. For the first time, the GeC+ molecule was characterized. The dissociation energy (D0) of the ground state (X3∏) of GeC is equal to 3.70 eV, showing good agreement with the theoretical result (3.90 eV) of Sari and colleagues. These results, however, are considerably smaller than the experimental value of 4.72 eV. The dissociation energy of the ground state (X3∑−) of GeSi is equal to 2.90 eV, and it is in very good agreement with the experimental value (3.08 eV). The most favorable transitions are A3∑− (GeC) → X4∑− (GeC+), A3∑− (GeC) → b2∏ (GeC+) and X3∑− (GeSi) → X4∑− (GeSi+), which present very few peaks in the spectra. © 2006 Wiley Periodicals, Inc. J Quantum Chem, 2006
Measurement of paclitaxel and its metabolites in human plasma using liquid chromatography/ion trap mass spectrometry with a sonic spray ionization interface
Authors: Gréen Henrik , Vretenbrant Karin , Norlander Björn , Peterson Curt 
Published: June 2006

AbstractA quantitative liquid chromatography/ion trap mass spectrometry method for the simultaneous determination of paclitaxel, 6α‐hydroxypaclitaxel and p‐3′‐hydroxypaclitaxel in human plasma has been developed and validated. 6α‐,p‐3′‐Dihydroxypaclitaxel was also quantified using paclitaxel as a reference and docetaxel as an internal standard. The substances were extracted from 0.500 mL plasma using solid‐phase extraction. The elution was performed with acetonitrile and the samples were reconstituted in the mobile phase. Isocratic high‐performance liquid chromatography analysis was performed by injecting 50 µL of reconstituted material onto a 100 × 3.00 mm C12 column with a methanol:1% trifluoroacetic acid/ammonium trifluoroacetate in H2O 70:30 mobile phase at 350 µL/min. The [M+H]+ ions generated in the sonic spray ionization interface were isolated and fragmented using two serial mass spectrometric methods: one for paclitaxel (transition 854 → 569 & 551) and the dihydroxymetabolite (transition 886 → 585 & 567) and one for the hydroxy metabolites (transition 870 → 585 & 567; transition 870 → 569 & 551) and docetaxel ([M+Na]+, transition 830 → 550). Calibration curves were created ranging between 0.5 and 7500 ng/mL for paclitaxel, 0.5 and 750 ng/mL for 6α‐hydroxypaclitaxel, and 0.5 and 400 ng/mL for p‐3′‐hydroxypaclitaxel. Adduct ion formation was noted and investigated during method development and controlled by mobile phase optimization. In conclusion, a sensitive method for simultaneous quantification of paclitaxel and its metabolites suitable for analysis in clinical studies was obtained. Copyright © 2006 John Wiley & Sons, Ltd.