bluuebunny/crossref_metadata_2025_split huggingface dataset:
Thermo‐Responsive Nanogels Based on Poly[NIPAAm‐graft‐(2‐alkyl‐2‐oxazoline)]s Crosslinked in the Micellar State
Authors: Zschoche Stefan , Rueda Juan , Boyko Volodymyr , Krahl Franziska , Arndt Karl‐Friedrich , Voit Brigitte 
Published: February 2010

AbstractGraft copolymers with thermo‐sensitive PNIPAAm backbone and hydrophilic PEtOxa graft chains demonstrated typical amphiphilic behavior. For specific compositions stable micelle‐like aggregates were formed depending on the temperature. Applying long polyoxazoline side chains ($\overline {DP} $ > 120), stable reversible micelle‐like aggregates with hydrodynamic radii of 30–40 nm could be obtained between 33 and 55 °C. These graft copolymers have been successfully crosslinked by electron‐beam irradiation in the micellar state yielding core/shell type nanogels with thermo‐reversible swelling behavior. The temperature dependent volume change of the new thermo‐responsive nanogels due to the phase transition of the PNIPAAm core has been verified by DLS.magnified image
Bari–Markus property for Riesz projections of 1D periodic Dirac operators
Authors: Djakov P. , Mityagin B. 
Published: February 2010

AbstractThe Dirac operators
equation image
with L2‐potentials
equation image
considered on [0, π] with periodic, antiperiodic or Dirichlet boundary conditions (bc), have discrete spectra, and the Riesz projections
equation image
are well‐defined for |n | ≥ N if N is sufficiently large. It is proved that
equation image
where P0 n, n ∈ ℤ, are the Riesz projections of the free operator.Then, by the Bari–Markus criterion, the spectral Riesz decompositions
equation image
converge unconditionally in L2 (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Weighted anisotropic product Hardy spaces and boundedness of sublinear operators
Authors: Bownik Marcin , Li Baode , Yang Dachun , Zhou Yuan 
Published: February 2010

AbstractLet A1 and A2 be expansive dilations, respectively, on ℝn and ℝm. Let A ≡ (A1, A2) and 𝒜p(A) be the class of product Muckenhoupt weights on ℝn × ℝm for p ∈ (1, ∞]. When p ∈ (1, ∞) and w ∈ 𝒜p(A), the authors characterize the weighted Lebesgue space Lp w(ℝn × ℝm) via the anisotropic Lusin‐area function associated with A. When p ∈ (0, 1], w ∈ 𝒜∞(A), the authors introduce the weighted anisotropic product Hardy space Hp w (ℝn × ℝm; A) via the anisotropic Lusin‐area function and establish its atomic decomposition. Moreover, the authors prove that finite atomic norm on a dense subspace of Hp w (ℝn×ℝm; A) is equivalent with the standard infinite atomic decomposition norm. As an application, the authors prove that if T is a sublinear operator and maps all atoms into uniformly bounded elements of a quasi‐Banach space ℬ︁, then T uniquely extends to a bounded sublinear operator from Hp w (ℝn × ℝm; A) to ℬ︁. The results of this paper improve the existing results for weighted product Hardy spaces and are new even in the unweighted anisotropic setting (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Discrepancy of Hammersley points in Besov spaces of dominating mixed smoothness
Authors: Hinrichs Aicke 
Published: February 2010

AbstractWe study the discrepancy function of two‐dimensional Hammersley type point sets in the unit square. It is well‐known that the symmetrized Hammersley point set achieves the asymptotically best possible rate for the L2‐norm of the discrepancy function. In this paper we consider the norm of the discrepancy function of Ham¬mersley type point sets in Besov spaces of dominating mixed smoothness and show that it achieves the optimal rate under appropriate assumptions on the set and the smoothness parameter of the Besov space. Our proof relies on a characterization of the Besov spaces of dominating mixed smoothness via coefficients in the Haar expansion and the computation of the Haar expansion of the discrepancy function of Hammersley type point sets (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Molecular structure of nitrophenylO‐glycosides in relation to their redox potentials
Authors: Gubica Tomasz , Temeriusz Andrzej , Pawłowski Paweł , Stroka Jadwiga 
Published: February 2010

AbstractThe effect of the non‐electroactive groups on the redox potentials of the active centres of 26 nitrophenylO‐glycosides possessing various substituents has been studied electrochemically using cyclic voltammetry. The potentials of both redox processes, a two‐electron quasi‐reversibleR‐NHOH/R‐NO (Ef) and four‐electron irreversibleR‐NO2/R‐NHOH (Epc(I)) systems, have been determined and compared for all the compounds under investigations. The nitrophenylO‐glycosides were chosen as model compounds as they significantly vary in many aspects of their structure such as: (i) the isomeric substitution of nitro group in benzene ring to the sugar moiety (ortho,metaandparaisomers); (ii) the size of sugar moieties (the derivatives of mono‐ and disaccharides); (iii) the presence and absence of additional groups in saccharidic fragments (e.g. pentose and hexose); (iv) functionalisation of hydroxyl groups (free or acetylated hydroxyl groups) and (v) absolute configurations of selected sugar carbon atoms (e.g. the pairs of anomers). Among other effects, a significant variation in the increasing order of the two‐electron quasi‐reversible (Ef,ortho > meta > para) and four‐electron irreversible (Epc(I),meta > ortho > para) redox processes has been found and explained taking into account the negative inductive effect (–I) caused by the glycosidic oxygen atom that facilitates the electroreduction of the nitro group, and the positive mesomeric effect (+M) which makes the electroreduction more difficult. Copyright © 2010 John Wiley & Sons, Ltd.
Combined experimental and theoretical studies of the elimination kinetic of 2‐methoxytetrahydropyran in the gas phase
Authors: Rosas Felix , Domínguez Rosa M. , Mora José R. , Marquez Edgar , Córdova Tania , Chuchani Gabriel 
Published: February 2010

AbstractThe products formed in 2‐methoxytetrahydropyran elimination reaction in the gas phase are 3, 4‐dihydro‐2H‐pyran and methanol. The kinetic study was carried out in a static system, with the vessels deactivated with allyl bromide, and the presence of the free radical suppressor toluene. Temperature and pressure ranges were 400–450 °C and 25–83 Torr, respectively. The process is homogeneous, unimolecular, and follows a first‐order rate law. The observed rate coefficient is represented by the following equation: log k (s−1) = (13.95 ± 0.15) − (223.1 ± 2.1) (kJ mol−1) (2.303RT)−1. The reactant exists mainly in two low energy chair‐like conformations, with the 2‐methoxy group in axial or equatorial position. However, the transition state (TS) for the elimination of the two conformers is the same. Theoretical calculations of this reaction were carried for two possible mechanisms from these conformations by using DFT functionals B3LYP, MPW1PW91, and PBE with the basis set 6‐31G(d,p) and 6‐31G++(d,p). The calculation results demonstrate that 2‐methoxytetrahydropyran exists mainly in two conformations, with the 2‐methoy group in axial or equatorial position, that are thermal in equilibrium. The average thermodynamic and kinetic parameters, taking into account the populations of the conformers in the equilibrium, are in good agreement with experimental values at B3LYP/6‐31++(d,p) level of theory. Copyright © 2010 John Wiley & Sons, Ltd.
Protein profiling in pathology: Analysis and evaluation of 239 frozen tissue biopsies for diagnosis of B‐cell lymphomas
Authors: Jansen Corine , Feuth Ton , Raemaekers John M. M. , Rijntjes Jos , Meijer Jos W. , Westenend Pieter J. , van Baarlen Joop , van Krieken Johan H. J. M. , Hebeda Konnie M. , Groenen Patricia J. T. A. 
Published: February 2010

AbstractPurpose: We determined the potential value of protein profiling of tissue samples by assessing how precise this approach enables discrimination of B‐cell lymphoma from reactive lymph nodes, and how well the profiles can be used for lymphoma classification.Experimental design: Protein lysates from lymph nodes (n=239) from patients with the diagnosis of reactive hyperplasia (n=44), follicular lymphoma (n=63), diffuse large B‐cell lymphoma (n=43), mantle cell lymphoma (n=47), and chronic lymphocytic leukemia/small lymphocytic B‐cell lymphoma (n=42) were analysed by SELDI‐TOF MS. Data analysis was performed by (i) classification and regression tree‐based analysis and (ii) binary and polytomous logistic regression analysis.Results: After internal validation by the leave‐one‐out principle, both the classification and regression tree and logistic regression classification correctly identified the majority of the malignant (87 and 96%, respectively) and benign cases (73 and 75%, respectively). Classification was less successful since approximately one‐third of the cases of each group were misclassified according to the histological classification. However, an additional mantle cell lymphoma case that was misclassified as chronic lymphocytic leukemia/small lymphocytic B‐cell lymphoma initially was identified based on the protein profile.Conclusions and clinical relevance: SELDI‐TOF MS protein profiling allows for reliable identification of the majority of malignant lymphoma cases; however, further validation and testing robustness in a diagnostic setting is needed.
Effects of endurance exercise on the urinary proteome analyzed by 2‐D PAGE and Orbitrap MS
Authors: Kohler Maxie , Walpurgis Katja , Thomas Andreas , de Maree Markus , Mester Joachim , Schänzer Wilhelm , Thevis Mario 
Published: February 2010

AbstractPurpose: Exercise‐induced proteinuria is a well‐known phenomenon and the influence of parameters such as intensity and duration was studied extensively. Usually, total protein or albumin was measured for diagnosis of a proteinuria, and the present study was performed to search for qualitative differences in the urinary proteome before and after endurance exercise.Experimental design: Urine samples were concentrated and proteins separated by means of 2‐D PAGE. Proteins differing in the investigated groups were identified by nano‐UPLC‐Orbitrap MS after trypsin digestion.Results: The study yielded several proteins such as hemopexin, albumin, orosomucoid 1, transferrin or carbonic anhydrase 1 that were elevated after a marathon run in comparison to a control group. These are linked to physiological changes resulting from endurance exercise such as destruction of erythrocytes or increased fat metabolism. On the contrary, 2‐D PAGE profiles of athletes at rest did not differ from those of control samples.Conclusions and clinical relevance:The study is a starting point to build up individual 2‐D PAGE protein maps of athletes. Further studies will investigate intra‐individual differences and further exercise parameters, which potentially lead to a physiological monitoring system for athletes in training and competition and may also complement the blood passport in doping control.
Studies of insect peptides alloferon, Any‐GS and their analogues. Synthesis and antiherpes activity
Authors: Kuczer Mariola , Dziubasik Katarzyna , Midak‐Siewirska Anna , Zahorska Renata , Łuczak Mirosław , Konopińska Danuta 
Published: February 2010

AbstractThe subject of these studies was synthesis and determination of biological properties of a series of insect peptides, such as alloferon, Any‐GS and their analogues. The synthesis of 14 peptides was performed by the solid‐phase method. Biological effect of these peptides was evaluated by the antiviral test against Human Herpes Virus type 1 (HHV‐1) in vitro using a Vero cell line. It was found that the investigated peptides inhibit the replication of HHV‐1 in Vero cells. Copyright © 2010 European Peptide Society and John Wiley & Sons, Ltd.
On the estimation of disease prevalence by latent class models for screening studies using two screening tests with categorical disease status verified in test positives only
Authors: Chu Haitao , Zhou Yijie , Cole Stephen R. , Ibrahim Joseph G. 
Published: February 2010

AbstractTo evaluate the probabilities of a disease state, ideally all subjects in a study should be diagnosed by a definitive diagnostic or gold standard test. However, since definitive diagnostic tests are often invasive and expensive, it is generally unethical to apply them to subjects whose screening tests are negative. In this article, we consider latent class models for screening studies with two imperfect binary diagnostic tests and a definitive categorical disease status measured only for those with at least one positive screening test. Specifically, we discuss a conditional‐independent and three homogeneous conditional‐dependent latent class models and assess the impact of misspecification of the dependence structure on the estimation of disease category probabilities using frequentist and Bayesian approaches. Interestingly, the three homogeneous‐dependent models can provide identical goodness‐of‐fit but substantively different estimates for a given study. However, the parametric form of the assumed dependence structure itself is not ‘testable’ from the data, and thus the dependence structure modeling considered here can only be viewed as a sensitivity analysis concerning a more complicated non‐identifiable model potentially involving a heterogeneous dependence structure. Furthermore, we discuss Bayesian model averaging together with its limitations as an alternative way to partially address this particularly challenging problem. The methods are applied to two cancer screening studies, and simulations are conducted to evaluate the performance of these methods. In summary, further research is needed to reduce the impact of model misspecification on the estimation of disease prevalence in such settings. Copyright © 2010 John Wiley & Sons, Ltd.
Controlling ecological bias in evidence synthesis of trials reporting on collapsed and overlapping covariate categories
Authors: Govan L. , Ades A. E. , Weir C. J. , Welton N. J. , Langhorne P. 
Published: February 2010

AbstractMeta‐analysis of randomized controlled trials based on aggregated data is vulnerable to ecological bias if trial results are pooled over covariates that influence the outcome variable, even when the covariate does not modify the treatment effect, or is not associated with the treatment. This paper shows how, when trial results are aggregated over different levels of covariates, the within‐study covariate distribution, and the effects of both covariates and treatments can be simultaneously estimated, and ecological bias reduced. Bayesian Markov chain Monte Carlo methods are used. The method is applied to a mixed treatment comparison evidence synthesis of six alternative approaches to post‐stroke inpatient care. Results are compared with a model using only the stratified covariate data available, where each stratum is treated as a separate trial, and a model using fully aggregated data, where no covariate data are used. Copyright © 2010 John Wiley & Sons, Ltd.
Seasonal variation in soil CO2 efflux in evergreen coniferous and broad‐leaved deciduous forests in a cool‐temperate forest, central Korea
Authors: Lee Na‐yeon , Koo Jin‐Woo , Noh Nam Jin , Kim Joon , Son Yowhan 
Published: February 2010

AbstractWe measured the soil surface CO2 efflux (RS) from January 2005 to December 2006 in two neighboring stands in Gwangneung Forest, central Korea: evergreen coniferous forest (Abies holophylla, stand A) and broad‐leaved deciduous forest (Quercus‐dominated, stand Q). Regarding seasonal variation, RS rate was low during the winter and early spring months in each stand and peaked in late July [1170 (stand A) and 1130 (stand Q) in 2005, and 1000 (stand A) and 740 (stand Q) mg CO2 m−2 h−1 in 2006]. RS rate was higher in stand A than in stand Q during most of the growing season. The pattern of summer rainfall differed between 2005 and 2006. RS rate for both stands was suppressed significantly by the droughts in June 2005 and September 2006. After the heavy rainfall of July 2006, RS rate was lower than in July 2005 in both stands, but this decrement was much greater in stand Q than in stand A. In midsummer (August) 2006, under higher soil temperature (ST) and lower soil water content (SWC) conditions than in August 2005, RS rate of stand A was lower than that in August 2005, whereas stand Q showed no marked change. The exponential relationship between ST and RS accounted for approximately 91–97% of the RS variability in each stand and in each year. In stand A, the application of a second‐order polynomial function indicated a significant correlation between SWC and RS when the soil was warm (ST > 15°C). Our results suggest that the seasonality of RS is strongly affected by the pattern of summer rainfall even in an Asia monsoon climate regime. In addition, the vegetation type (i.e., evergreen coniferous forest vs. broad‐leaved deciduous forest) plays a significant role in response of RS to various environmental fluctuations such as drought, heavy rainfall, and hot‐dry condition.
Trans‐Membrane Uptake and Intracellular Metabolism of Fatty Acids in Atlantic Salmon (Salmo salar L.) Hepatocytes
Authors: Zhou Jishu , Stubhaug Ingunn , Torstensen Bente E. 
Published: February 2010

AbstractTo elucidate if the trans‐membrane uptake of fatty acids is protein‐mediated, the uptake of oleic acid (18:1n‐9), linoleic acid (18:2n‐6), alpha‐linolenic acid (18:3n‐3), eicosapentaenoic acid (20:5n‐3) and docosahexaenoic acid (22:6n‐3) was investigated in vitro in Atlantic salmon (Salmo salar L.) primary hepatocytes. Firstly, optimal fatty acid incubation time and concentration were established for trans‐membrane 18:n‐9 uptake. Based on saturation kinetics, a 2‐h incubation time and 37.5 μM were used for the following experiments. Secondly, in order to identify whether trans‐membrane fatty acid uptake in hepatocytes was mainly passive or protein mediated, hepatocytes were pre‐incubated with membrane protein inhibitors followed by 2 h of incubation with [1‐14C] labelled 18:1n‐9, 18:2n‐6, 18:3n‐3, 20:5n‐3 and 22:6n‐3. Fatty acid uptake into hepatocytes was highest with 20:5n‐3 and 22:6n‐3 and lowest with 18:1n‐9. Phloretin was the most potent fatty acid uptake inhibitor, inhibiting uptake in the following order: 20:5n‐3 > 18:3n‐3 = 22:6n‐3 > 18:2n‐6 > 18:1n‐9. The uptake of FA in Atlantic salmon hepatocytes seem to be due to both saturable and inhibitable protein mediated uptake, as well as passive uptake processes with more unsaturated and long fatty acids (20:n‐3 > 22:6n‐3 = 18:3n‐3 > 18:2n‐6) being more dependent on membrane protein mediated uptake compared to 18:1n‐9.
Effects of maternal hyperhomocysteinemia induced by methionine intake on oxidative stress and apoptosis in pup rat brain
Authors: Koz Sema T. , Gouwy Nevhayat T. , Demir Nevgul , Nedzvetsky Viktor S. , Etem Ebru , Baydas Giyasettin 
Published: February 2010

AbstractMaternal hyperhomocysteinemia is associated with a number of complications such as preeclampsia syndrome, thromboembolic events, repeated miscarriages, abruptio placentae, in utero fetal death, intrauterine fetal growth restriction and fetal neural tube defects. However, little is known about the mechanism of homocysteine on the degeneration of fetal brain. Thus, our study is aimed to investigate the effects of maternal hyperhomocysteinemia on oxidative stress and apoptosis in pup brain. Hyperhomocysteinemia was induced in female rats by way of administrating methionine dissolved in water at a dose of 1 g/kg body weight throughout the pregnancy. After delivery, level of lipid peroxidation (LPO; as malondialdehyde + 4‐hydroxyalkenals) was determined in various fractions of pub brains. Furthermore, DNA fragmentation, levels of Bcl‐2 protein and p53 mRNA expression were determined to evaluate apoptosis. Significant elevation was found in the levels of LPO in subcellular fractions of pup brains delivered from hyperhomocysteinemic mothers. DNA fragmentation, a hallmark of apoptosis was observed in the brain of pups of homocysteine group while significant reduction was seen in the levels of anti‐apoptotic Bcl‐2 levels. In addition, maternal hyperhomocysteinemia increased cerebral p53 mRNA expression above the control value. As a conclusion, we demonstrate and suggest that the pups of hyperhomocysteinemic mothers have an increased oxidative stress in brain tissues. The increased oxidative stress appears to cause apoptosis and cell death. These results may be significant to understand chronic pathology of the complications of hyperhomocysteinemia and congenital malformations of fetuses.
The influence of acoustic and static stimuli on development of inner ear sensory epithelia
Authors: Rot Irena , Kablar Boris 
Published: February 2010

AbstractMechanical stimuli affect differentiation of specific cell types in several organs of mouse fetuses that develop without any skeletal musculature. To that end, we employed Myf5−/−:MyoD−/− mouse embryos that completely lack skeletal musculature, and analyzed the development of sensory fields in the inner ear. Amyogenic fetuses lack skeletal muscles that move the chain of three middle ear ossicles which normally transfers sound vibrations. They also cannot tilt their head, which prevents the perception of angular acceleration.While our findings in the spiral organ of Corti are surprisingly normal, our results show that the development of cristae ampullaris, vestibular sensory fields sensitive to the angular acceleration, was the most affected. In cristae, hair cells and supporting cells were significantly smaller in the mutant embryos, but hair cells completely lacked tenascin, while supporting cells were more numerous. In maculae, supporting cells were significantly smaller but more numerous in the mutants. Here, we propose that our finding of a specific type I hair cell absence in the mutant's crista may now be employed in the identification of a profile of genes specific for the lacking cell type.
Drug treatment of Alzheimer's disease patients leads to expression changes in peripheral blood cells
Authors: Calciano Margaret A. , Zhou Weiyin , Snyder Peter J. , Einstein Richard 
Published: February 2010

BackgroundIncreasing cholinergic activity has been the primary mechanism for treating dementia due to Alzheimer's disease. However, the effectiveness of cholinesterase inhibitors (ChEIs) is still widely debated. The identification of specific biomarkers capable of identifying patients more likely to respond to these treatments could potentially provide specific evidence to clearly address this controversy through patient stratification. The goal of this study was to determine the feasibility of discovering biomarkers specific for the treatment of Alzheimer's disease.MethodsPeripheral blood was collected from a cohort of patients treated with different ChEIs. Total RNA was isolated and profiled on the human Genome‐Wide SpliceArray (GWSA) to test the feasibility of discriminating the different treatment subgroups of subjects based on the expression patterns generated from the Genome‐Wide SpliceArray.ResultsSpecific expression differences were identified for the various treatment groups that lead to a clear separation between patients treated with ChEIs versus naïve patients when Principal Component Analysis was performed on probe sets selected for differential expression. In addition, specific probe sets were identified to be dependent on the inhibitor used among the treated patients.ConclusionsDistinct separation between non‐treated, galantamine, donepezil, and rivastigmine‐treated patients was clearly identified based on small sets of expression probes. The ability to identify drug‐specific treatment expression differences strengthens the potential for using peripheral gene signatures for the identification of individuals responding to drug treatment.