bluuebunny/crossref_metadata_2025_split huggingface dataset:
Facilitating reproductive choices: the impact of health services on the experiences of young women with breast cancer
Authors: Lee Rebecca J. , Wakefield Ann , Foy Sharon , Howell Sacha J. , Wardley Andrew M. , Armstrong Anne C. 
Published: September 2010

AbstractObjective: Chemotherapy and hormone treatments carry significant implications on the fertility of young women with breast cancer. Increasingly, nulliparous women experience fertility dilemmas due to rising survival rates and pregnancy delay. This qualitative study investigated women's responses to being told that treatments affected their fertility and how their interactions with health services impacted on their experiences.Methods: Twenty‐four women under 40 years participated in three focus groups using a flexible interview structure. Data were analysed using content analysis and participants subsequently member checked the themes generated.Results: The priority for most women was survival, although women without children were more willing to take risks. Many women felt that pregnancy after breast cancer and methods of egg harvesting carried a significant risk to survival and fears appeared to be increased by conflicting advice from health professionals. Overall, the women felt the cancer, its treatment options and the health service itself had each robbed them of choice. Hence, with hindsight, many said they would have welcomed an open and honest discussion with a fertility expert to maximise their options.Conclusions: Young women with breast cancer face complex decisions regarding their fertility and treatment options. Survival remains the priority for the majority of women. Although there is a paucity of evidence concerning many fertility issues, it is essential that available options and any potential risks are discussed in a coherent, objective fashion. Early referral to specialist fertility services that provide clear, cohesive advice can aid informed decision making. Copyright © 2010 John Wiley & Sons, Ltd.
Lung function in children with repaired tracheo‐oesophageal fistula using the forced oscillation technique
Authors: Harrison Joanne , Martin Jessica , Crameri Joe , Robertson Colin F. , Ranganathan Sarath C. 
Published: September 2010

AbstractBackgroundTracheo‐oesophageal fistula (TOF) and oesophageal atresia (OA) are congenital anomalies commonly associated with pulmonary complications during early childhood. This study investigated the role of the forced oscillation technique (FOT) in assessing lung function in young children with repaired TOF/OA.MethodsForty children with repaired TOF/OA of median (range) age 8.0 (3.3–10.6) years, and 20 healthy children without TOF aged 6.1 (3.1–10.8) years were studied. FOT measurements were attempted in all subjects and spirometry only in those 6 years and above. Resistance and reactance (both hPasL−1) at 6 Hz (Rrs6 and Xrs6, respectively) and 8 Hz (Rrs8 and Xrs8) measured using FOT, and forced expired volume in 1 sec (FEV1), forced vital capacity, functional residual capacity, total lung capacity, and residual volume (all L) obtained from spirometry or plethysmography were compared with reference values and expressed as z‐scores.ResultsTechnically acceptable measurements of Rrs6, Rrs8, Xrs6, Xrs8, Fdep, and Fres were obtained in 37 children with TOF and 20 healthy children without TOF, respectively. Those with TOF had significantly higher mean (SD) z‐scores for Rrs6 [0.99 (0.75)] versus healthy children without TOF [0.31 (0.69)] and lower mean (SD) z‐scores for Xrs6 [−1.04 (1.07)] versus healthy children without TOF [−0.34 (0.83)]. Spirometry was successful in 24 of the 29 with TOF in whom it was attempted and all healthy children without TOF. Mean (SD) z‐score for FEV1 was significantly lower in those with TOF [−0.86 (1.13)] versus healthy children without TOF [0.67 (0.54)]. z‐Scores for Rrs6 and FEV1 were significantly correlated (r = −0.49; P = 0.003).ConclusionsChildren with repaired TOF have diminished lung function compared with healthy children. FOT is sensitive and correlates well with standard spirometry. It can be used to measure lung function in younger children when spirometry is difficult to perform and should be considered as an objective method for monitoring clinical progress in young children with TOF. Pediatr Pulmonol. 2010;45:1057–1063. © 2010 Wiley‐Liss, Inc.
Experimental optimization of protein refolding with a genetic algorithm
Authors: Anselment Bernd , Baerend Danae , Mey Elisabeth , Buchner Johannes , Weuster‐Botz Dirk , Haslbeck Martin 
Published: August 2010

AbstractRefolding of proteins from solubilized inclusion bodies still represents a major challenge for many recombinantly expressed proteins and often constitutes a major bottleneck. As in vitro refolding is a complex reaction with a variety of critical parameters, suitable refolding conditions are typically derived empirically in extensive screening experiments. Here, we introduce a new strategy that combines screening and optimization of refolding yields with a genetic algorithm (GA). The experimental setup was designed to achieve a robust and universal method that should allow optimizing the folding of a variety of proteins with the same routine procedure guided by the GA. In the screen, we incorporated a large number of common refolding additives and conditions. Using this design, the refolding of four structurally and functionally different model proteins was optimized experimentally, achieving 74–100% refolding yield for all of them. Interestingly, our results show that this new strategy provides optimum conditions not only for refolding but also for the activity of the native enzyme. It is designed to be generally applicable and seems to be eligible for all enzymes.
A lead discovery strategy driven by a comprehensive analysis of proteases in the peptide substrate space
Authors: Sukuru Sai Chetan K. , Nigsch Florian , Quancard Jean , Renatus Martin , Chopra Rajiv , Brooijmans Natasja , Mikhailov Dmitri , Deng Zhan , Cornett Allen , Jenkins Jeremy L. , Hommel Ulrich , Davies John W. , Glick Meir 
Published: August 2010

AbstractWe present here a comprehensive analysis of proteases in the peptide substrate space and demonstrate its applicability for lead discovery. Aligned octapeptide substrates of 498 proteases taken from the MEROPS peptidase database were used for the in silico analysis. A multiple‐category naïve Bayes model, trained on the two‐dimensional chemical features of the substrates, was able to classify the substrates of 365 (73%) proteases and elucidate statistically significant chemical features for each of their specific substrate positions. The positional awareness of the method allows us to identify the most similar substrate positions between proteases. Our analysis reveals that proteases from different families, based on the traditional classification (aspartic, cysteine, serine, and metallo), could have substrates that differ at the cleavage site (P1–P1′) but are similar away from it. Caspase‐3 (cysteine protease) and granzyme B (serine protease) are previously known examples of cross‐family neighbors identified by this method. To assess whether peptide substrate similarity between unrelated proteases could reliably translate into the discovery of low molecular weight synthetic inhibitors, a lead discovery strategy was tested on two other cross‐family neighbors—namely cathepsin L2 and matrix metallo proteinase 9, and calpain 1 and pepsin A. For both these pairs, a naïve Bayes classifier model trained on inhibitors of one protease could successfully enrich those of its neighbor from a different family and vice versa, indicating that this approach could be prospectively applied to lead discovery for a novel protease target with no known synthetic inhibitors.
Functional hot spots in human ATP‐binding cassette transporter nucleotide binding domains
Authors: Kelly Libusha , Fukushima Hisayo , Karchin Rachel , Gow Jason M. , Chinn Leslie W. , Pieper Ursula , Segal Mark R. , Kroetz Deanna L. , Sali Andrej 
Published: August 2010

AbstractThe human ATP‐binding cassette (ABC) transporter superfamily consists of 48 integral membrane proteins that couple the action of ATP binding and hydrolysis to the transport of diverse substrates across cellular membranes. Defects in 18 transporters have been implicated in human disease. In hundreds of cases, disease phenotypes and defects in function can be traced to nonsynonymous single nucleotide polymorphisms (nsSNPs). The functional impact of the majority of ABC transporter nsSNPs has yet to be experimentally characterized. Here, we combine experimental mutational studies with sequence and structural analysis to describe the impact of nsSNPs in human ABC transporters. First, the disease associations of 39 nsSNPs in 10 transporters were rationalized by identifying two conserved loops and a small α‐helical region that may be involved in interdomain communication necessary for transport of substrates. Second, an approach to discriminate between disease‐associated and neutral nsSNPs was developed and tailored to this superfamily. Finally, the functional impact of 40 unannotated nsSNPs in seven ABC transporters identified in 247 ethnically diverse individuals studied by the Pharmacogenetics of Membrane Transporters consortium was predicted. Three predictions were experimentally tested using human embryonic kidney epithelial (HEK) 293 cells stably transfected with the reference multidrug resistance transporter 4 and its variants to examine functional differences in transport of the antiviral drug, tenofovir. The experimental results confirmed two predictions. Our analysis provides a structural and evolutionary framework for rationalizing and predicting the functional effects of nsSNPs in this clinically important membrane transporter superfamily.
Prostate cancer risk and exposure to pesticides in British Columbia Farmers
Authors: Band Pierre R. , Abanto Zenaida , Bert Joel , Lang Barbara , Fang Raymond , Gallagher Richard P. , Le Nhu D. 
Published: August 2010

AbstractBACKGROUNDSeveral epidemiologic studies have reported an increased risk of prostate cancer among farmers. Our aim was to assess the risk of developing prostate cancer in relation to exposure to specific active compounds in pesticides.METHODA case–control approach was used with 1,516 prostate cancer patients and 4,994 age‐matched internal controls consisting of all other cancer sites excluding lung cancer and cancers of unknown primary site. Lifetime occupational history was obtained through a self‐administered questionnaire and used in conjunction with a job exposure matrix to estimate the participants' lifetime cumulative exposure to approximately 180 active compounds in pesticides. Conditional logistic regression was used to assess prostate cancer risk, adjusting for potential confounding variables and effect modifiers. These include age, ethnicity, alcohol consumption, smoking, education, and proxy respondent.RESULTS AND CONCLUSIONSThe significant association between prostate cancer risk and exposure to DDT (OR = 1.68; 95% CI: 1.04–2.70 for high exposure), simazine (OR = 1.89; 95% CI: 1.08–3.33 for high exposure), and lindane (OR = 2.02; 95% CI: 1.15–3.55 for high exposure) is in keeping with those previously reported in the literature. We also observed a significant excess risk for several active ingredients that have not been previously reported in the literature such as dichlone, dinoseb amine, malathion, endosulfan, 2,4‐D, 2,4‐DB, and carbaryl. Some findings in our study were not consistent with those reported in the literature, including captan, dicamba, and diazinon. It is possible that these findings showed a real association and the inconsistencies reflected differences of characteristics between study populations. Prostate 71: 168–183, 2011. © 2010 Wiley‐Liss, Inc.
Monitoring of QoI fungicide resistance in Plasmopara viticola populations in Japan
Authors: Furuya Seiichi , Mochizuki Mai , Saito Seiya , Kobayashi Hironori , Takayanagi Tsutomu , Suzuki Shunji 
Published: August 2010

AbstractBACKGROUND: The increasing occurrence of QoI fungicide resistance in Plasmopara viticola (Berk. & MA Curtis) Berl. & DeToni populations is becoming a serious problem in the control of grapevine downy mildew. In Japan, the existence of QoI‐fungicide‐resistant P. viticola was reported in 2009.RESULTS: The QoI fungicide resistance in P. viticola samples collected from vineyards in Japan in 2008 and 2009 was monitored. Resistant P. viticola were detected in the regions where QoI fungicides have been introduced in accordance with the pest management programme, whereas in Hokkaido vineyards, where QoI fungicides have not yet been introduced, QoI‐fungicide‐resistant P. viticola were not found.CONCLUSION: Japan comprises thousands of islands and is physically isolated from other countries by the sea. Monitoring the emergence, incidence and distribution of QoI fungicide resistance in P. viticola populations in Japan is necessary to improve pest management strategies for downy mildew disease in Japanese vineyards. Copyright © 2010 Society of Chemical Industry
Optimization of oxidative folding methods for cysteine‐rich peptides: a study of conotoxins containing three disulfide bridges
Authors: Steiner Andrew M. , Bulaj Grzegorz 
Published: September 2010

AbstractThe oxidative folding of small, cysteine‐rich peptides to selectively achieve the native disulfide bond connectivities is critical for discovery and structure‐function studies of many bioactive peptides. As the propensity to acquire the native conformation greatly depends on the peptide sequence, numerous empirical oxidation methods are employed. The context‐dependent optimization of these methods has thus far precluded a generalized oxidative folding protocol, in particular for peptides containing more than two disulfides. Herein, we compare the efficacy of optimized solution‐phase and polymer‐supported oxidation methods using three disulfide‐bridged conotoxins, namely µ‐SIIIA, µ‐KIIIA and ω‐GVIA. The use of diselenide bridges as proxies for disulfide bridges is also evaluated. We propose the ClearOx‐assisted oxidation of selenopeptides as a fairly generalized oxidative folding protocol. Copyright © 2010 European Peptide Society and John Wiley & Sons, Ltd.
Native chemical ligation of hydrophobic peptides in organic solvents
Authors: Dittmann Marc , Sauermann Jörg , Seidel Ralf , Zimmermann Wolfgang , Engelhard Martin 
Published: September 2010

AbstractThe application of chemistry to hydrophobic peptides and membrane‐spanning helices is hampered by the fact that they are only poorly soluble in aqueous buffers and that they have a tendency for aggregation. These properties lead to difficulties when purifying them after chemical synthesis and particularly interfere with native chemical ligation. Here, we describe native chemical ligation of model peptides in the organic solvent dimethylformamide (DMF) under anhydrous conditions. Best results concerning yields and complete solubility are obtained if thiophenole is used in the presence of LiCl. These conditions might be applicable also for the ligation of transmembrane helices. Copyright © 2010 European Peptide Society and John Wiley & Sons, Ltd.
Efficient synthesis of an (aminooxy) acetylated‐somatostatin derivative using (aminooxy)acetic acid as a ‘carbonyl capture’ reagent
Authors: Mezö Gábor , Szabó Ildikó , Kertész István , Hegedüs Rózsa , Orbán Erika , Leurs Ulrike , Bösze Szilvia , Halmos Gábor , Manea Marilena 
Published: September 2010

AbstractOwing to the high chemoselectivity between an aminooxy function and a carbonyl group, oxime ligation is one of the most preferred procedures for the preparation of peptide conjugates. However, the sensitivity of (aminooxy)acetylated peptides to ketones and aldehydes makes their synthesis and storage difficult. In our study, we established the efficient synthesis of an (aminooxy)acetylated‐somatostatin derivative in the presence of free (aminooxy)acetic acid, which was used as a ‘carbonyl capture’ reagent in the final cleavage step. This (aminooxy)acetylated compound was further used for the chemoselective ligation (oxime bond formation) with daunorubicin and 4‐fluorobenzaldehyde leading to the formation of conjugates with potential applications in targeted cancer chemotherapy and positron emission tomography. Copyright © 2010 European Peptide Society and John Wiley & Sons, Ltd.
Magnetic, electric and dielectric properties of FeCo alloy nanoparticles dispersed in amorphous matrix
Authors: Thirumal E. , Prabhu D. , Chattopadhyay K. , Ravichandran V. 
Published: August 2010

AbstractNanocrystalline Fe53Co47 alloy was synthesized by a single‐step transmetallation chemical method at room temperature. The Fe53Co47 alloy nanoparticles of 77 and 47 wt% were dispersed in silica matrix by the sol–gel process using tetraethyl orthosilcate. Structural studies reveal that the as‐prepared alloy powders are in bcc phase and silica is in an amorphous state. The phase‐transition temperature and Mössbauer spectra analysis of the Fe–Co alloy establishes the homogeneous alloy formation. A saturation magnetization of 218 emu/g was obtained for pure FeCo alloy at room temperature. Scanning electron microscopic analysis demonstrates the hollow‐sphere morphology for FeCo alloy particles. Magnetic nanocomposite consisting of 47 wt% FeCo–silica shows enhanced thermal stability over the native FeCo alloy. Electrical and dielectric properties of 47 wt% FeCo–silica nanocomposites were investigated as a function of frequency and temperature. It was found that the dielectric constants and dielectric loss were stable throughout the measured temperature (310–373 K). Our results indicate that FeCo–silica nanocomposite is a promising candidate for high‐frequency applications.
PrOAlN dielectrics for metal insulator semiconductor stacks
Authors: Henkel Karsten , Torche Mohamed , Sohal Rakesh , Karavaev Konstantin , Burkov Yevgen , Schwiertz Carola , Schmeißer Dieter 
Published: August 2010

AbstractThis work focuses on praseodymium oxide films as a high‐k material on silicon and silicon carbide (SiC) in metal insulator semiconductor samples. The electrical results are correlated to spectroscopic findings on this material system. Strong interfacial reactions between the praseodymium oxide and the semiconductor as well as silicon inter‐diffusion into the high‐k material are observed. The importance of a buffer layer is discussed and its optimisation is addressed, too. In particular the improvement of the performance by the introduction of an aluminium oxynitride buffer layer, which acts as an inter‐diffusion barrier and reduces the leakage current, the interface state density and the equivalent oxide thickness is demonstrated.
Magnetism in graphite induced by irradiation of hydrogen or helium ions – A comparative study
Authors: Makarova Tatiana L. , Shelankov Andrei L. , Serenkov Igor T. , Sakharov Vladimir I. 
Published: August 2010

AbstractTo identify the origin of defect‐induced magnetism in ion‐irradiated graphite, a comparative study of samples of graphite irradiated with hydrogen H+ and helium He+ ions is performed. Directionally dependent magnetic properties, atomic/magnetic force microscopy studies suggest that the induced magnetic moments are located along the vertically aligned grain boundaries. Compared to the case of the hydrogen ion irradiation, the optimal helium irradiation dose is an order of magnitude lower. From this we conclude that the hydrogen chemistry is essentially irrelevant, and the ferromagnetic‐like response of the irradiated graphite is due to structural defects regardless of their origin.magnified image
Surface of HOPG irradiated with H+ and He+ at similar doses.
Carbon nanotubes growth: From entanglement to vertical alignment
Authors: Esconjauregui Santiago , Fouquet Martin , Bayer Bernhard , Robertson John 
Published: August 2010

AbstractBy using oxidising environments during catalyst formation, SiO2‐supported thin Ni films restructure into small nanoparticles of reduced mobility that nucleate vertically‐aligned carbon nanotubes (CNTs) by base mode. Conversely, typical reducing environments yield entangled nanotubes only, which grow by tip mode. The selection of pretreatment environments proves control over nanotube morphology and growth mode, and can be of interest for the surface growth of other nanostructures.
Evaluation of defect concentration in doped SWCNT
Authors: Kalbac Martin , Kavan Ladislav 
Published: August 2010

AbstractIn the present study we analyze and discus Raman spectra of doped SWCNTs. We focus on the development of the integral area of the D mode (AD), the TG mode (ATG) and the G′ mode (AG′). It is shown that area of the D band is significantly attenuated in doped carbon nanotubes samples for both semiconducting and metallic tubes. A similar dependence on the doping as in the case of the area of the D mode was found also for the area of the TG and the G′ mode. The area of the G′ mode was found to be more significantly dependent on the electrode potential than the area of the TG mode. However, this difference is only small, hence the AD/AG′ and AD/ATG ratios give only slightly different results in evaluation of the amount of defects in doped SWCNT samples.
Tip‐enhanced Raman scattering along a single wall carbon nanotubes bundle
Authors: Peica Niculina , Thomsen Christian , Maultzsch Janina 
Published: August 2010

AbstractRaman scattering is a common technique for studying carbon nanotubes due to the possibility to observe the radial breathing mode (RBM), which is used for identification of single wall carbon nanotubes “SWCNT.” Using tip‐enhanced Raman scattering (TERS) we show along a small SWCNTs bundle that the RBMs are well visible in near‐field, even if they are not observable in the far‐field. Different Raman intensities in TERS for the D, G, and 2D modes at six different positions along a SWCNTs bundle were observed. We discuss this strong dependence of the TERS signal on the position of the tip on the sample and on the distance between the tip and the sample.
A comparative study of field emission from NanoBuds, nanographite and pure or N‐doped single‐wall carbon nanotubes
Authors: Kleshch V. I. , Susi T. , Nasibulin A. G. , Obraztsova E. D. , Obraztsov A. N. , Kauppinen E. I. 
Published: August 2010

AbstractField emission characteristics of multi‐emitter flat cathodes prepared from NanoBuds, few‐layer graphite flakes (nanographite, NG) and pure or N‐doped single‐wall carbon nanotubes (SWNTs) have been examined. The cathodes demonstrated a low‐voltage electron emission with the threshold field values of few Volts per micron, which were ascribed to the high‐aspect ratio of nanocarbons. The films of NanoBuds and NG possess excellent emission pattern homogeneity with an emission site density of more than 105 cm−2. This is much higher than for cathodes made of conventional SWNT films. It was found that the achievable maximal current density depends on the type of carbon material and reaches 10 A/cm2 for NanoBuds film, while for the NG film cathodes, it is about one order of magnitude less. Possible mechanisms responsible for the experimentally observed differences are discussed. The materials examined are of great interest due to their high‐emission characteristics and are promising for the development of new types of vacuum electronic devices.