bluuebunny/crossref_metadata_2025_split huggingface dataset:
Diagnosis and treatment of recurrent laryngeal cancer following initial nonsurgical therapy
Authors: Agra Ivan Marcelo Gonçalves , Ferlito Alfio , Takes Robert P. , Silver Carl E. , Olsen Kerry D. , Stoeckli Sandro J. , Strojan Primož , Rodrigo Juan P. , Gonçalves Filho João , Genden Eric M. , Haigentz Missak , Khafif Avi , Weber Randal S. , Zbären Peter , Suárez Carlos , Hartl Dana M. , Rinaldo Alessandra , Kim Kwang Hyun , Kowalski Luiz P. 
Published: April 2011

AbstractSurgery is the preferred modality for curative treatment of recurrent laryngeal cancer after failure of nonsurgical treatments. Patients with initial early‐stage cancer experiencing recurrence following radiotherapy often have more advanced‐stage tumors by the time the recurrence is recognized. About one third of such recurrent cancers are suitable for conservation surgery. Endoscopic resection with the CO2 laser or open partial laryngectomy (partial vertical, supracricoid, or supraglottic laryngectomies) have been used. The outcomes of conservation surgery appear better than those after total laryngectomy, because of selection bias. Transoral laser surgery is currently used more frequently than open partial laryngectomy for treatment of early‐stage recurrence, with outcomes equivalent to open surgery but with less associated morbidity. Laser surgery has also been employed for selective cases of advanced recurrent disease, but patient selection and expertise are required for application of this modality to rT3 tumors. In general, conservation laryngeal surgery is a safe and effective treatment for localized recurrences after radiotherapy for early‐stage glottic cancer. Recurrent advanced‐stage cancers should generally be treated by total laryngectomy. © 2011 Wiley Periodicals, Inc. Head Neck, 2012.
Efficient Synthesis of a Styryl Analogue of (2S,3R,4E)‐N2‐Octadecanoyl‐4‐tetradecasphingenine via Cross‐Metathesis Reaction
Authors: Kumar Gulshan , Kaur Sukhbir , Singh Vasundhara 
Published: April 2011

AbstractThe first total synthesis of sphingolipid (2S,3R,4E)‐N2‐octadecanoyl‐4‐tetradecasphingenine (1a), a natural sphingolipid isolated from Bombycis Corpus 101A, and of its styryl analogue 1b was achieved in good overall yield (Schemes 1 and 2). The key step involved the installation with (E) stereoselectivity of a long lipophilic chain or phenyl group on allyl alcohol derivative 3 via a cross‐metathesis reaction (→5a or 5b). The N‐Boc protected 3 was easily accessible from (S)‐Garner aldehyde.
Two Unusual Phenolic Substances and One New Xanthone from Hypericum sampsonii
Authors: Xin Wen‐Bo , Jin Gui‐Lin , Mao Zhu‐Jun , Qin Lu‐Ping 
Published: April 2011

AbstractSampsone A (1), a novel prenylated aromatic lactone, and sampsone B (2), an unusual dihydrodibenzodioxinone, together with sampsone C (3), a new xanthone, were isolated from the aerial parts of Hypericum sampsonii. Their structures were determined by spectroscopic methods which were mainly 1D‐ and 2D‐NMR techniques, and the structure of sampsone B (2) was also confirmed by X‐ray crystallographic analysis. All of these compounds were evaluated for in vitro antibacterial activity against methicillin‐resistant Staphylococcus aureus (MRSA). Only sampsone A showed moderate antibacterial activities at a minimum inhibitory concentration (MIC) of 32 μg/ml.
Ophiobolin Sesterterpenoids and Pyrrolidine Alkaloids from the Sponge‐Derived Fungus Aspergillus ustus
Authors: Liu Hong‐Bing , Edrada‐Ebel RuAngelie , Ebel Rainer , Wang Yao , Schulz Barbara , Draeger Siegfried , Müller Werner E. G. , Wray Victor , Lin Wen‐Han , Proksch Peter 
Published: April 2011

AbstractChemical examination of the fungus Aspergillus ustus isolated from the Mediterranean sponge Suberites domuncula yielded the five new ophiobolin‐type sesterterpenoids 1–5 and the two new pyrrolidine alkaloids 6 and 7, together with the known compound aurantiamine and cerebroside D. The structures of the new compounds were unambiguously elucidated on the basis of extensive spectroscopic‐data analysis (1D‐ and 2D‐NMR, MS, and UV) and comparison with literature data. All compounds were evaluated for their cytotoxicity against murine lymphoma cell line L5178Y.
An Efficient Stereoselective Approach for the Synthesis of (+)‐(4S,5S)‐Muricatacin
Authors: Srinivas Chiguru , Naga Sesha Sai Pavan Kumar Chebolu , China Raju Bhimapaka , Jayathirtha Rao Vaidya 
Published: April 2011

AbstractAn efficient stereoselective total synthesis of (+)‐(4S,5S)‐muricatacin was accomplished in good yields from inexpensive, commercially available chemicals ((+)‐diethyl tartrate (DET) and undecan‐1‐ol) by utilizing Mitsunobu and JuliaKocienski reactions, Wittig homologation, Swern oxidation, and lactonization.
Syntheses of Prekinamycin and a Tetracyclic Quinone from Common Synthetic Intermediates
Authors: Kimura Shingo , Kobayashi Satoshi , Kumamoto Takuya , Akagi Aki , Sato Naomi , Ishikawa Tsutomu 
Published: April 2011

AbstractTowards total synthesis of a series of kinamycin and related antibiotics via common synthetic intermediates, total synthesis of prekinamycin was achieved via Suzuki coupling of naphthaleneboronic acid and bromobenzene derivative, intramolecular FriedelCrafts reaction of 2‐(naphthalen‐2‐yl)benzoic acid, and diazotization in ten steps from 3,5‐dimethylphenol. Synthetic studies towards kinamycin antibiotics was also examined, and the tetracyclic quinone core for kinamycins was synthesized. Palladium‐catalyzed site‐selective hydroxylation of a benzoic acid derivative with the AB‐D ring part was successfully applied to the selective D‐ring functionalizations.
Oligonucleotide Analogues with Integrated Bases and Backbone. Part 27
Authors: Herdeis Lorenz , Bernet Bruno , Augustine Anu , Kälin Roland E. , Brändli André W. , Vasella Andrea 
Published: April 2011

AbstractThe (chloromethyl)cytidine 7 was obtained from alcohol 4 that was synthesized from the protected cytidine 3 by C(6)‐formylation and reduction. Thioacetate 10 was obtained from the cytidine 2, and thioacetate 8 from a Mitsunobu reaction of alcohol 6. The thiomethylene‐linked dinucleoside 11 was synthesized by thioether formation between the 6‐(chloromethyl)cytidine 7 and the thiolate generated by S‐deacetylating and N‐debenzoylating the cytidine‐5′‐thioacetate 10. Dinucleoside 11 was desilylated to 12, and fully deprotected to 13. Similarly to 11, the C(6)‐substituted analogue 14 was obtained from 7 and the C(6)‐substituted 8. Stepwise deprotection of 14 provided 15–17, and complete deprotection gave 18. The thioacetylated and N‐benzoylated dinucleoside 21 was obtained from the methanesulfonate 9 and the thiolate that was generated from thioacetate 8. Similarly, 7 and 8 yielded 19 that was transformed into the methanesulfonate 20. The tetranucleoside 23 was synthesized from the methanesulfonate 20 and the thiol derived from 21. It was debenzoylated to 23 and completely deprotected to 24.The partially protected dinucleosides 11, 14, and 15, and the tetranucleoside 23 pair strongly in CDCl3. The crystal structure of 11⋅MeOH shows the formation of an antiparallel cyclic duplex possessing nearly orthogonal base pairs due to MeOH acting as H‐acceptor from one base pair and H‐donor to the other base pair. A large distance of ca. 6 Å between the base pairs of the cyclic duplexes was predicted by Maruzen modeling. It is corroborated by the absence of base stacking in CHCl3 solution of the duplexes formed by the (self‐complementary) dinucleosides 11, 14, and 15, as evidenced by a weak temperature dependence of the CD spectra. The association constants for 11, 14, 15, and 23 were calculated from the concentration dependence of the chemical shift of H2NC(4). No concentration dependence of the H2NC(4) signals was observed for solutions of 23 in CDCl3, (D6)acetone, CD3CN, (D8)THF, (D5)pyridine, and CDCl3/(D6)DMSO 4 : 1. As a consequence of the strong association, the association constant for 23 had to be determined in CD3CN/(D6)DMSO 4 : 1. The temperature dependence of the CD spectra of the fully deprotected 18 und 24, but not of 13, in H2O is rationalized by base stacking of the hydroxymethylated cytosine moieties that associate by intermolecular H‐bonds of HOCH2C(6/I) to an acceptor of unit I. The 1H‐NMR spectrum of 18 and 24, but not of 13, shows a 9 : 1 mixture of the monoplex and the base‐stacked duplex.
Tracking hydrological responses of a thermokarst lake in the Old Crow Flats (Yukon Territory, Canada) to recent climate variability using aerial photographs and paleolimnological methods
Authors: MacDonald Lauren A. , Turner Kevin W. , Balasubramaniam Ann M. , Wolfe Brent B. , Hall Roland I. , Sweetman Jon N. 
Published: April 2011

AbstractRecent studies using remote sensing analysis of lake‐rich thermokarst landscapes have documented evidence of declining lake surface area in response to recent warming. However, images alone cannot identify whether these declines are due to increasing frequency of lake drainage events associated with accelerated thermokarst activity or to increasing evaporation in response to longer ice‐free season duration. Here, we explore the potential of combining aerial photograph time series with paleolimnological analyses to track changes in hydrological conditions of a thermokarst lake in the Old Crow Flats (OCF), Canada, and to identify their causes. Images show that the water level in lake OCF 48 declined markedly sometime between 1972 and 2001. In a sediment core from OCF 48, complacent stratigraphic profiles of several physical, geochemical, and biological parameters from ∼1874–1967 indicate hydro‐limnological conditions were relatively stable. From ∼1967–1989, declines in organic matter content, organic carbon isotope values, and pigment concentrations are interpreted to reflect an increase in supply of minerogenic sediment, and subsequent decline in aquatic productivity, caused by increased thermo‐erosion of shoreline soils. Lake expansion was likely caused by increased summer rainfall, as recorded by increased cellulose‐inferred lake‐water oxygen isotope compositions. Stratigraphic trends defining the lake expansion phase terminated at ∼1989, which likely marks the year when the lake drained. Above‐average precipitation during the previous year probably raised the lake level and promoted further thermo‐erosion of the shoreline soils that caused the lake to drain. These are meteorological conditions that have led to other recent lake‐drainage events in the OCF. Thus, the decline in lake level, evident in the aerial photograph from 2001, is unlikely to have been caused by evaporation, but rather is a remnant of a drainage event that took place more than a decade earlier. After drainage, the lake began to refill, and most paleolimnological parameters approach levels that are similar to those during the stable phase. These findings indicate that combined use of aerial images and paleolimnological methods offers much promise for identifying the hydrological consequences of recent climatic variations on thermokarst lakes. Copyright © 2011 John Wiley & Sons, Ltd.
Gas Phase Cucurbit[n]uril Chemistry
Authors: Yang Fan , Dearden David V. 
Published: April 2011

AbstractThe chemistry of cucurbit[n]urils is commanding increasing interest because of potential applications of these molecules in supramolecular structures; in drug encapsulation, protection, and delivery; and in sensitive new analytical assays. It is widely recognized that the binding properties of cucurbit[n]urils are sensitively dependent on solvents and counterions. Hence, gas phase studies, where neither solvent nor counterion species are present, are vital to gain fundamental understanding of cucuribituril complexes and to facilitate future applications. We use Fourier transform ion cyclotron resonance mass spectrometry (FTICR‐MS) and ion mobility techniques to investigate the gas phase chemistry of cucurbit[n]urils and related species, addressing problems such as how trapping molecules inside the cucurbit[n]uril cavity affects the binding of cations on the rims, the mechanism of exchange of bound/trapped species, and the origin of the large pKa shifts that occur for trapped guests. This paper is a review of our work.
The Potential of Cucurbit[n]urils in Drug Delivery
Authors: Walker Shonagh , Oun Rabbab , McInnes Fiona J. , Wheate Nial J. 
Published: April 2011

AbstractIn this paper we review cucurbit[n]urils (CB[n]), a relatively new family of macrocycles that has shown potential in improving drug delivery. Encapsulation of drugs within the homologues CB[6], CB[7], or CB[8] can impart enhanced chemical and physical stability, improve drug solubility, and control drug release. The formulation of CB[n] into a dosage form suitable for clinical use is a non‐trivial task, because the free macrocycle and its host‐drug complex generally exhibit pseudo‐polymorphism in the solid state. Despite this, cucurbiturils have been included in tablets for oral delivery and inserts for nasal delivery. Here we examine the potential use of cucurbiturils in drug delivery in the context of getting a new drug into clinical trials and discuss what further research is needed in this area.
Quality of attachment, perinatal risk, and mother–infant interaction in a high‐risk premature sample
Authors: Udry‐Jørgensen Laura , Pierrehumbert Blaise , Borghini Ayala , Habersaat Stephanie , Forcada‐Guex Margarita , Ansermet François , Muller‐Nix Carole 
Published: April 2011

AbstractThirty‐three families, each with a premature infant born less than 33 gestational weeks, were observed in a longitudinal exploratory study. Infants were recruited in a neonatal intensive care unit, and follow‐up visits took place at 4 months and 12 months of corrected age. The severity of the perinatal problems was evaluated using the Perinatal Risk Inventory (PERI; A.P. Scheiner & M.E. Sexton, 1991). At 4 months, mother–infant play interaction was observed and coded according to the CARE‐index (P.M. Crittenden, 2003); at 12 months, the Strange Situation Procedure (SSP; M.D.S. Ainsworth, M.C. Blehar, E. Waters, & S. Wall, 1978) was administered. Results indicate a strong correlation between the severity of perinatal problems and the quality of attachment at 12 months. Based on the PERI, infants with high medical risks more frequently tended to be insecurely attached. There also was a significant correlation between insecure attachment and dyadic play interaction at 4 months (i.e., maternal controlling behavior and infant compulsive compliance). Moreover, specific dyadic interactive patterns could be identified as protective or as risk factors regarding the quality of attachment. Considering that attachment may have long‐term influence on child development, these results underline the need for particular attention to risk factors regarding attachment among premature infants.
Histidine146 of human serum albumin plays a prominent role at the interface of subdomains IA and IIA in allosteric ligand binding
Authors: Kaneko Kenichi , Chuang Victor Tuan Giam , Minomo Ai , Yamasaki Keishi , Bhagavan Nadhipuram V. , Maruyama Toru , Otagiri Masaki 
Published: April 2011

AbstractFatty acids are endogenous ligands of human serum albumin (HSA) that induce conformational changes and participate in allosteric ligand binding to HSA. In a previous study, we showed that, when myristate (MYR) is present, the binding of [14C]ketoprofen (KP) to subdomain IA of HSA was increased, indicating that, when MYR binds to HSA, a new binding site in formed in that region. Meanwhile, an N‐B transition has been reported to increase the binding of ligands at alkaline pH when the status of albumin is the B‐conformer. Six histidine single mutants of HSA, H9A, H39A, H67A, H105A, H128A and H146A were produced and photolabeled with [14C]KP at pH 6.5, 7.4 and 8.2 and the role of each histidine in causing the N‐B transition induced allosteric ligand binding was examined. Cyanogen bromide cleavage of the photolabeled native HSA showed that subdomain IA was the site of the allosteric binding of KP at pH 8.2. From the photolabeling results, H146 was found to play a prominent role whilst H128 played little or no role in the allosteric binding. However, the remaining 4 mutants did not show a clear photolabeling pattern that was similar to either native HSA or H146A and, as a result, no firm conclusions can be made. An additional histidine mutant, H146I, was produced to confirm the results for H146A. A similar experiment using H146I showed that a benzene ring‐like structure at position 146 is required for the allosteric ligand binding to occur. © 2011 IUBMB IUBMB Life, 63(4): 277–285, 2011
Calculation of binding free energies of inhibitors to plasmepsin II
Authors: Steiner Denise , Oostenbrink Chris , Diederich François , Zürcher Martina , van Gunsteren Wilfred F. 
Published: April 2011

AbstractAn understanding at the atomic level of the driving forces of inhibitor binding to the protein plasmepsin (PM) II would be of interest to the development of drugs against malaria. To this end, three state of the art computational techniques to compute relative free energies—thermodynamic integration (TI), Hamiltonian replica‐exchange (H‐RE) TI, and comparison of bound versus unbound ligand energy and entropy—were applied to a protein‐ligand system of PM II and several exo‐3‐amino‐7‐azabicyclo[2.2.1]heptanes and the resulting relative free energies were compared with values derived from experimental IC50 values. For this large and flexible protein‐ligand system, the simulations could not properly sample the relevant parts of the conformational space of the bound ligand, resulting in failure to reproduce the experimental data. Yet, the use of Hamiltonian replica exchange in conjunction with thermodynamic integration resulted in enhanced convergence and computational efficiency compared to standard thermodynamic integration calculations. The more approximate method of calculating only energetic and entropic contributions of the ligand in its bound and unbound states from conventional molecular dynamics (MD) simulations reproduced the major trends in the experimental binding free energies, which could be rationalized in terms of energetic and entropic characteristics of the different structural and physico‐chemical properties of the protein and ligands. © 2011 Wiley Periodicals, Inc. J Comput Chem, 2011
Supercritical water oxidation of flammable industrial wastewaters: economic perspectives of an industrial plant
Authors: Vadillo Violeta , García‐Jarana M. Belén , Sánchez‐Oneto Jezabel , Portela Juan Ramón , de la Ossa Enrique J. Martínez 
Published: April 2011

AbstractBACKGROUND: Supercritical water oxidation (SCWO) is a promising technology that respects the environment, destroys wastes and allows energy recovery. This process has been applied to many model compounds and real wastewaters at laboratory scale. However, SCWO treatments at pilot plant scale of real wastewaters are scarce. The application of this technology to industrial wastewaters has drawbacks such as corrosion, salt deposition and high cost, so industrial scale‐up has been delayed.RESULTS: In a first stage, for safety reasons the feasibility of SCWO applied to flammable industrial wastewaters was evaluated at laboratory scale in an isothermal plug flow reactor with low concentrations (3–10 g COD L−1), at a constant pressure of 250 bar and at different temperatures in the range 350–500 °C. In a second stage, experiments were conducted with much higher concentrations (20–90 g COD L−1) in a SCWO reactor at pilot plant scale. Experiments at pilot plant scale demonstrated the possibility of working under autothermal conditions and the results were used to estimate the treatment costs for a SCWO plant with a capacity of 1 m3 h−1.CONCLUSION: Results demonstrated the technical feasibility of using a SCWO process to treat flammable industrial wastewater at pilot plant scale due to the absence of operational drawbacks related to the flammability of this wastewater, such as plugging, pressurization or preheating problems and uncontrolled reactions (explosion, etc.). The economic feasibility was demonstrated, especially bearing in mind the energy recovery optimization. Copyright © 2011 Society of Chemical Industry
Development of histamine‐immunoreactivity in the Central nervous system of the two locust species Schistocerca gregaria and Locusta migratoria
Authors: PÄtschke Arne , Bicker Gerd 
Published: April 2011

AbstractLocusts are attractive model preparations for cellular investigations of neurodevelopment. In this study, we investigate the immunocytochemical localization of histamine in the developing ventral nerve cord of two locust species, Schistocerca gregaria and Locusta migratoria. Histamine is the fast neurotransmitter of photoreceptor neurons in the compound eye of insects, but it is also synthesized in interneurons of the central nervous system. In the locust ventral nerve cord, the pattern of histamine‐immunoreactive neurons follows a relatively simple bauplan. The histaminergic system comprises a set of single, ascending projection neurons that are segmentally arranged in almost every neuromere. The neurons send out their axons anteriorly, forming branches and varicosities throughout the adjacent ganglia. In the suboesophageal ganglion, the cell bodies lie in a posteriolateral position. The prothoracic ganglion lacks histaminergic neurons. In the posterior ganglia of the ventral nerve cord, the somata of the histaminergic neurons are ventromedially positioned. Histamine‐immunoreactivity starts around 50% of embryonic development in interneurons of the brain. Subsequently, the neurons of the more posterior ganglia of the ventral nerve cord become immunoreactive. From 60% embryonic development, the pattern of soma staining in the nerve cord appears mature. Around 65% of embryonic development, the photoreceptor cells show histamine‐immunoreactivity. The histaminergic innervation of the neuropile develops from the central branches toward the periphery of the ganglia and is completed right before hatching. Microsc. Res. Tech. 2011. © 2011 Wiley‐Liss, Inc.
An efficient one‐pot synthesis of bis‐indolylmethanes containing pyrazolyl catalyzed by Brønsted acidic ionic liquid under solvent‐free conditions
Authors: Liu Chenjiang , Yu Chuanji 
Published: April 2011

AbstractBrønsted acidic ionic liquid [PyNCH2CO2H][HSO4] was found to be an effective catalyst for the condensation reactions of indoles with various 4‐formylpyrazoles to afford the corresponding bis‐indolylmethanes containing pyrazole under solvent‐free conditions. The satisfactory results were obtained with excellent yields, short reaction time, and simplicity in the experimental procedure. J. Heterocyclic Chem., (2011).