bluuebunny/crossref_metadata_2025_split huggingface dataset:
Single-centre experience of laparoscopic pancreatic surgery
Authors: Røsok B I , Marangos I P , Kazaryan A M , Rosseland A R , Buanes T , Mathisen Ø , Edwin B 
Published: April 2010

Abstract

Background
Laparoscopic resection is regarded as safe and feasible in selected patients with benign pancreatic tumours. Few data exist on laparoscopic surgery for malignant lesions and larger neoplasms in unselected patients.

Methods
The study included all patients admitted to Oslo University Hospital, Rikshospitalet, from March 1997 to March 2009 for surgery of lesions in the body and tail of the pancreas, and selected patients with lesions in the pancreatic head, who underwent surgery by a laparoscopic approach with curative intent.

Results
A total of 166 patients had 170 operations, including 138 pancreatic resections, 18 explorations, nine resections of peripancreatic tissue and five other therapeutic procedures. Four patients had repeat procedures. There were 53 endocrine tumours (31·0 per cent), 28 pancreatic carcinomas (16·4 per cent), five cases of metastases (2·9 per cent), 48 cystic tumours (28·1 per cent) and 37 other lesions (21·6 per cent). The total morbidity rate was 16·5 per cent. Fistula was the most common complication (10·0 per cent). Three patients needed reoperation for complications. There were three hospital deaths (1·8 per cent). Median hospital stay following surgery was 4 days.

Conclusion
Laparoscopic resection of lesions in the body and tail of the pancreas in an unselected patient series was safe and feasible, and should be the method of choice for this patient group in specialized centres.
Childhood antecedents of adult violent offending in a group of female felons
Authors: Lewis Catherine F. 
Published: April 2010

AbstractThe purpose of this study was to evaluate potential antecedents of violent felony arrest in a sample of female felons. Among male populations, early onset conduct disorder (CD) with progression to adult anti‐social personality disorder (ASPD) is associated with increased criminality and aggression. Conduct disorder is associated with a worsened trajectory of alcohol dependence in men. These factors likely have a synergistic contribution to male adult violent offending. Existing work suggests that CD, ASPD, and severe alcohol dependence may represent an externalizing endophenotype, which is, at least in part, genetically conferred. These associations have not been well studied in female populations. The author examined a sample (N = 130) of female mid‐sentence felons to determine associations between adult arrest for violent felony with child and young adult antecedents, including CD and alcohol dependence. Data were gathered through administration of the Semi‐Structured Assessment for the Genetics of Alcoholism II (SSAGA II). CD had high prevalence (40.8%), as did ASPD (31.4%) and alcohol dependence (43.8%). Women convicted of violent felonies were more likely to have CD with progression to ASPD, and alcohol dependence. Both alcohol dependence and CD were independently associated with violent offending. These data suggest that the most serious female offenders have psychopathology similar to that of males and that the trajectory of disease and etiology of violent behavior may not be as gender specific as previously presumed. Copyright © 2010 John Wiley & Sons, Ltd.
Comment on “The Interplay between Steric and Electronic Effects in SN2 Reactions”
Authors: van Zeist Willem‐Jan , Bickelhaupt F. Matthias 
Published: April 2010

AbstractWe respond to a paper by Fernández, Frenking, and Uggerud (FFU: Chem. Eur. J. 2009, 15, 2166) in which they conclude that not steric hindrance but reduced electrostatic attraction and reduced orbital interactions are responsible for the SN2 barrier, in particular in the case of more highly substituted substrates, for example, F− + C(CH3)3F. We disagree with this conclusion, which we show is the result of neglecting geometry relaxation processes that are induced by increased Pauli repulsion in the sterically congested SN2 transition state.
Additive Tuning of Redox Potential in Metallacarboranes by Sequential Halogen Substitution
Authors: González‐Cardoso Patricia , Stoica Anca‐Iulia , Farràs Pau , Pepiol Ariadna , Viñas Clara , Teixidor Francesc 
Published: April 2010

AbstractThe first artificially made set of electron acceptors is presented that are derived from a unique platform Cs[3,3′‐Co(C2B9H11)2], for which the redox potential of each differs from its predecessor by a fixed amount. The sequence of electron acceptors is made by substituting one, two, or more hydrogen atoms by chlorine atoms, yielding Cs[3,3′‐Co(C2B9H11−yCly)(C2B9H11−zClz)]. The higher the number of chlorine substituents, the more prone the platform is to be reduced. The effect is completely additive, so if a single substitution implies a reduction of 0.1 V of the redox potential of the parent complex, then ten substitutions imply a reduction of 1 V.
Rhodamine B Piperazinoacetohydrazine: A Water‐Soluble Spectroscopic Reagent for Pyruvic Acid Labeling
Authors: Jia Jia , Wang Ke , Shi Wen , Chen Suming , Li Xiaohua , Ma Huimin 
Published: April 2010

AbstractA new water‐soluble reagent, rhodamine B piperazinoacetohydrazine (RBPH), with improved spectroscopic and reaction properties, has been developed and characterized for pyruvic acid labeling. The reagent RBPH is designed and synthesized by using rhodamine B as a spectroscopic unit, and hydrazine as a carbonyl‐specific labeling unit; the two units are connected by a well‐chosen linker of piperazine, which prohibits the formation of the nonfluorescent spirocyclic structure of rhodamine B, thereby keeping the spectroscopic response of the reagent in a stable state. Such a design enables RBPH not only to maintain its excellent spectroscopic properties over a wide pH range, but also to exist as a stable cation with high water solubility. Moreover, the hydrazino group of RBPH is expected to react selectively with carbonyl compounds under mild conditions through the rapid formation of hydrazones. These important features make RBPH of great potential use in the labeling of aldehydes or ketones in various biosystems, and such an application of RBPH as a precolumn derivatizing reagent has been successfully demonstrated on the analysis of pyruvic acid in human serum by high‐performance liquid chromatography with common UV/Vis detection.
The Electronic Structure and Photochemistry of Group 6 Bimetallic (Fischer) Carbene Complexes: Beyond the Photocarbonylation Reaction
Authors: Lage Marta L. , Fernández Israel , Mancheño María J. , Gómez‐Gallego Mar , Sierra Miguel A. 
Published: April 2010

AbstractThe UV spectra of Group 6 metal carbene complexes bearing a CpM(CO)3 (Cp=cyclopentadienyl) moiety bonded to the carbene carbon atom exhibit a redshift of the absorption maxima at higher wavelengths with respect to the parent monometallic complexes. This redshift is partly due to a higher occupation on the pz atomic orbital of the carbene carbon atom. Time‐dependent DFT calculations accurately assign this band to a metal‐to‐ligand charge‐transfer transition, thus showing that the presence of a second metal center does not affect the nature of the transition. However, the photochemical reactivity of Group 6 metal carbene complexes bearing a CpM(CO)3 moiety strongly depends on the nature of this metal fragment. A new photoslippage reaction leading to fulvenes occurs when Mn‐derived products 11 a, 11 b, and 12 a are irradiated (both Cr and W derivatives), whereas Re‐derived product 11 c behaves like standard Fischer complexes and yields the usual photocarbonylation products. A new photoreduction process occurring in the metallacyclopropanone intermediate is also observed for these complexes. Both computational and deuteration experiments support this unprecedented photoslippage process. The key to this differential photoreactivity seems to be the M–Cp back‐donation, which hampers the slippage process for Re derivatives and favors the carbonylation reaction.
Colloidal Noble‐Metal and Bimetallic Alloy Nanocrystals: A General Synthetic Method and Their Catalytic Hydrogenation Properties
Authors: Song Shuyan , Liu Ruixia , Zhang Yu , Feng Jing , Liu Dapeng , Xing Yan , Zhao Fengyu , Zhang Hongjie 
Published: April 2010

AbstractA general single‐step strategy has been developed for the direct thermal decomposition of noble‐metal salts in octadecylamine to synthesize octahedron‐ and rod‐shaped noble‐metal aggregates and monodisperse noble‐metal or bimetallic alloy nanocrystals without introducing any additive into the system. It has presented a facile and economic way to fabricate these nanocrystals, especially alloy nanocrystals, which does not require a post‐synthesis solid‐state annealing process. The morphology of the nanocrystals can be easily controlled by tuning the synthetic temperature. Their ability to catalyze heterogeneous Suzuki coupling reactions has been investigated and showed satisfactory catalytic activity. The catalytic performance of the monometallic and bimetallic alloy nanocrystals were also evaluated in the selective hydrogenation of citral in a conventional organic solvent (toluene) and a green solvent (supercritical carbon dioxide, scCO2). Interestingly, the catalysts performed differently to each other when they were in scCO2 owing to the different morphology, which should be readily optimized for further use.
Hydrogels Composed of Organic Amphiphiles and α‐Cyclodextrin: Supramolecular Networks of Their Pseudorotaxanes in Aqueous Media
Authors: Taira Toshiaki , Suzaki Yuji , Osakada Kohtaro 
Published: April 2010

AbstractMixtures of N‐alkyl pyridinium compounds [py‐N‐(CH2)nOC6H3‐3,5‐(OMe)2]+(X−) (1bCl: n=10, X=Cl; 1cBr: n=12, X=Br) and α‐cyclodextrin (α‐CD) form supramolecular hydrogels in aqueous media. The concentrations of the two components influences the sol–gel transition temperature, which ranges from 7 to 67 °C. Washing the hydrogel with acetone or evaporation of water left the xerogel, and 13C CP/MAS NMR measurements, powder X‐ray diffraction (XRD), and scanning electron microscopy (SEM) revealed that the xerogel of 1bCl (or 1cBr) and α‐CD was composed of pseudorotaxanes with high crystallinity. 13C{1H} and 1H NMR spectra of the gel revealed the detailed composition of the components. The gel from 1bCl and α‐CD contains the corresponding [2]‐ and [3]pseudorotaxanes, [1b⋅(α‐CD)]Br and [1b⋅(α‐CD)2]Br, while that from 1cBr and α‐CD consists mainly of [3]pseudorotaxane [1c⋅(α‐CD)2]Br. 2D ROESY 1H NMR measurements suggested intermolecular contact of 3,5‐dimethoxyphenyl and pyridyl end groups of the axle component. The presence of the [3]pseudorotaxane is indispensable for gel formation. Thus, intermolecular interaction between the end groups of the axle component and that between α‐CDs of the [3]pseudorotaxane contribute to formation of the network. The supramolecular gels were transformed into sols by adding denaturing agents such as urea, C6H3‐1,3,5‐(OH)3, and [py‐N‐nBu]+(Cl−).
Tuning the Magnetic Moment of [Ru2(DPhF)3(O2CMe)L]+ Complexes (DPhF=N,N′‐Diphenylformamidinate): A Theoretical Explanation of the Axial Ligand Influence
Authors: Barral M. Carmen , Casanova David , Herrero Santiago , Jiménez‐Aparicio Reyes , Torres M. Rosario , Urbanos Francisco A. 
Published: April 2010

AbstractThe magnetic behaviour of the compounds containing the [Ru2(DPhF)3(O2CMe)]+ ion (DPhF−=N,N′‐diphenylformamidinate) shows a strong dependence on the nature of the ligand bonded to the axial position. The new complexes [Ru2(DPhF)3(O2CMe)(OPMe3)][BF4]⋅0.5 CH2Cl2 (1⋅ 0.5 CH2Cl2) and [Ru2(DPhF)3(O2CMe)(4‐pic)][BF4] (2) (4‐pic=4‐methylpyridine) clearly display this influence. Complex 1⋅0.5 CH2Cl2 shows a magnetic moment corresponding to a S=3/2 system affected by the common zero‐field splitting (ZFS) and a weak antiferromagnetic interaction, whereas complex 2 displays an intermediate behaviour between S=3/2 and S=1/2 systems. The experimental data of complex 1 are fitted with a model that considers the ZFS effect using the Hamiltonian ĤD=S⋅D⋅S. The weak antiferromagnetic coupling is introduced as a perturbation, using the molecular field approximation. DFT calculations demonstrate that, in the [Ru2(O2CMe)(DPhF)3(L)]+ complexes, the energy level of the metal–metal molecular orbitals is strongly dependent on the nature of the axial ligand (L). This study reveals that the increase in the π‐acceptor character of L leads to a greater split between the π* and δ* HOMO orbitals. The influence of the axial ligand in the relative energy between the doublet and quartet states in this type of complexes was also analysed. This study was performed on the new complexes 1⋅0.5 CH2Cl2 and 2. The previously isolated [Ru2(DPhF)3(O2CMe)(OH2)][BF4]⋅0.5 CH2Cl2 (3⋅ 0.5 CH2Cl2) and [Ru2(DPhF)3(O2CMe)(CO)][BF4]⋅CH2Cl2 (4⋅CH2Cl2) complexes were also included in this study as representative examples of spin‐admixed and low‐spin configurations, respectively. The [Ru2(DPhF)3(O2CMe)]+ (5) unit was used as a reference compound. These theoretical studies are in accordance with the different magnetic behaviour experimentally observed.
Total Synthesis of Punctaporonin C by a Regio‐ and Stereoselective [2+2]‐Photocycloaddition
Authors: Fleck Martin , Bach Thorsten 
Published: April 2010

AbstractThe unique sesquiterpene punctaporonin C was synthesized starting from commercially available 7‐tert‐butoxynorbornadiene in a linear sequence of 29 steps and with an overall yield of 0.65 %. Key step of the synthesis was an intramolecular [2+2]‐photocycloaddition, in which the two vinylic double bonds in a 1,3‐divinyl‐2‐cyclopentyl tetronate were differentiated by reaction with the photoexcited tetronate. The reaction gave regio‐ and diastereoselective access to the tricyclic core skeleton of punctaporonin C in 63 % yield. Additional studies related to the tetronate [2+2]‐photocycloaddition revealed that even diastereotopic vinylic double bonds in a 1,3‐divinyl‐2‐cyclopentyl tetronate can be differentiated (d.r. up to 78:22). In the further course of the total synthesis the complete tetracyclic oxatetracyclo[6.3.2.01, 4.05, 12]tridecane skeleton of punctaporonin C was established by an intramolecular aldol reaction, closing a seven‐membered oxepane ring. The nucleophilic methyl ketone employed in this step was generated by Wacker oxidation of the vinylic double bond, which was not involved in the [2+2]‐photocycloaddition. Several reactions employed in the synthetic sequence required adaptation to the rigid skeleton of punctaporonin C, for example, the reduction of a mesylate, the alkylation of a cyclobutane carboxylate, or the methyl addition to a prostereogenic carbonyl group.
Synthesis and application of 3‐substituted (S)‐BINOL as chiral ligands for the asymmetric ethylation of aldehydes
Authors: Zhang Zhi‐Guang , Dong Zhi‐Bing , Li Jin‐Shan 
Published: April 2010

AbstractA series of (S)‐BINOL ligands substituted at the 3 position with some five‐membered nitrogen‐containing aromatic heterocycles were effectively prepared and their catalytic abilities were evaluated in the asymmetric addition of diethylzinc to benzaldehyde in the presence of titanium tetraisopropoxide. Under the optimized reaction conditions, titanium complex of (S)‐3‐(1H‐benzimidazol‐1‐yl)‐1,1′‐bi‐2‐naphthol was found to be the most efficient catalyst for asymmetric ethylation of various aldehydes to generate the corresponding secondary alcohols in up to 99% yield and 91% ee. Chirality, 2010. © 2010 Wiley‐Liss, Inc.
(S)‐6‐Bromo‐BINOL‐based phosphoramidite ligand with C1 symmetry for enantioselective hydrogenation and allylic substitution
Authors: Gavrilov Konstantin N. , Benetsky Eduard B. , Boyko Vladimir E. , Rastorguev Eugenie A. , Davankov Vadim A. , Schäffner Benjamin , Börner Armin 
Published: April 2010

Abstract(S)‐6‐Br‐BINOL‐derived phosphoramidite, a simple monodentate ligand with a stereogenic center at the phosphorus atom, was synthesized for the first time. This stereoselector generated a high level of enantioselectivity (80–95% ee) in the rhodium‐catalyzed hydrogenation of α‐dehydrocarboxylic acid esters and was also successfully employed in the asymmetric palladium‐catalyzed allylic substitution of (E)‐1,3‐diphenylallyl acetate. The optical yield also showed significant dependence with reaction type: up to 70% ee for allylic amination, up to 75% ee for allylic sulfonylation, and up to 90% ee for allylic alkylation. Chirality, 2010. © 2010 Wiley‐Liss, Inc.
Highly enantiomeric reduction of acetophenone and its derivatives by locally isolated Rhodotorula glutinis
Authors: Zilbeyaz Kani , Kurbanoglu Esabi B. 
Published: April 2010

AbstractNinety isolates of microorganisms belonging to different taxonomical groups (30 bacteria, 20 yeast, and 40 fungi) were previously isolated from various samples. These isolates were screened as reducing agents for acetophenone 1a to phenylethanol 2a. It was found that the isolate EBK‐10 was the most effective biocatalyst for the enantioselective bioreduction of acetophenone. This isolate was identified as Rhodotorula glutinis by the VITEK 2 Compact system. The various parameters (pH 6.5, temperature 32°C, and agitation 200 rpm) of the bioreduction reaction was optimized, which resulted in conversions up to 100% with >99% enantiomeric excesses (ee) of the S‐configuration. The preparative scale bioreduction of acetophenone 1a by R. glutinis EBK‐10 gave (S)‐1‐phenylethanol 2a in 79% yield, complete conversion, and >99% ee. In addition, R.glutinis EBK‐10 successfully reduced various substituted acetophenones. Chirality, 2010. © 2010 Wiley‐Liss, Inc.
Stereospecific pharmacodynamics and chiral inversion of NG‐nitro‐arginine in the beagle dogs
Authors: Xin Yan‐Fei , Gu Li‐Qiang , Zhang Sheng , Bai Yun‐Sheng , Zhou Guo‐Liang , You Zhen‐Qiang , Xuan Yao‐Xian 
Published: April 2010

AbstractIn the present study, we analyzed the stereospecific pharmacodynamics and inversion of NG‐nitro‐arginine by an intravenous blous injection of L‐NG‐nitro‐arginine (L‐NNA) or D‐NG‐nitro‐arginine (D‐NNA) (10 mg/kg) in beagle dogs. Significant pressor responses were observed for both substances, though a similar maximum response induced by L‐NNA was reached at 120 min slower as compared with D‐NNA. The rise in mean arterial pressure (MAP) of D‐NNA dogs was also shown to be slower than the L‐NNA group. Our data showed that D‐NNA had no impact on MAP within 60 min after its injection. Plasma L‐NNA started to appear after 45 min posterior to the i.v. bolus injection of D‐NNA. This chiral inversion is unidirectional because no D‐NNA was not produced from L‐NNA. The pressor response in the D‐NNA‐injected dogs was well parallel to the plasma L‐NNA concentration. Similar disposition of NG‐nitro‐arginine enantiomers and 4% of chiral inversion ratio from D‐NNA to L‐NNA was found in the beagle dogs. Given thatD‐amino acid oxidase (DAAO) is the essential enzyme in chiral inversion of D‐NNA, we further compared the enzymatic activity of the renal DAAO between dogs and rats. Our data showed that dogs had a significantly lower enzymatic activity than rats, thus supported a lower inversion ratio of D‐NNA in dogs. Chirality, 2010. © 2010 Wiley‐Liss, Inc.
Changes in the plasma concentrations ofD‐kynurenine and kynurenic acid in rats after intraperitoneal administration of tryptophan enantiomers
Authors: Ishii Kana , Ogaya Tadahiro , Song Ziyu , Iizuka Hideaki , Fukushima Takeshi 
Published: April 2010

AbstractAn aqueous solution of enantiomerically pure tryptophan (Trp), namely,D‐Trp orL‐Trp (100 mg/kg), was administered intraperitoneally to male Sprague‐Dawley rats. The time‐course profiles of the rat plasma concentrations ofD‐kynurenine (KYN),L‐KYN, and kynurenic acid (KYNA), which are metabolites ofD‐ orL‐Trp, were investigated using high‐performance liquid chromatography (HPLC) systems that were reported in our previous study. The plasmaD‐KYN concentration increased after the administration ofD‐Trp, but this increase was not observed after the administration ofL‐Trp. The plasmaL‐KYN concentration increased after the administration ofL‐Trp, but no significant change was observed after the administration ofD‐Trp. The plasma KYNA concentration drastically increased in the case of rats administeredD‐Trp and those administeredL‐Trp. Additionally, an inhibitor ofD‐amino acid oxidase (DAAO), 5‐methylpyrazole‐3‐carboxylic acid (MPC) (50 mg/kg), was administrated to the rats 30 min before the administration ofD‐Trp. The preadministration of MPC remarkably increased theD‐KYN concentration and suppressed the production of KYNA. These results suggest that DAAO may contribute to the metabolism ofD‐KYN to KYNA in vivo. Chirality, 2010. © 2010 Wiley‐Liss, Inc.
NMR diffusion measurements under chemical exchange between sites involving a large chemical shift difference
Authors: Leclerc S. , Guendouz L. , Retournard A. , Canet D. 
Published: April 2010

AbstractThis study concerns the thallium‐205 cation in aqueous solution in the presence of a calixarene molecule. Although the measurement of the self‐diffusion coefficient of pure thallium (without calixarene in the aqueous solution) does not pose any particular problem, major difficulties are encountered with the standard method using gradient strength increment as soon as thallium is partly complexed by calixarene. With static magnetic field gradients, the NMR signal is so weak that it prevents any reliable measurement, whereas radio frequency (rf) field gradients lead to an unrealistic value of the diffusion coefficient. This failure is explained by the fact that thallium is in fast exchange between two sites (complexed and free thallium) thus exhibiting a single NMR signal although, in the course of the experiment, two signals, with an important difference in resonance frequencies (due to the large thallium chemical shift range), are effectively involved. With the objective to understand these quite unexpected observations, the theory underlying NMR diffusion experiments is first reviewed, and criteria of fast exchange are discussed for three parameters: chemical shifts, relaxation rates, and diffusion coefficients. It turns out that off‐resonance effects are responsible for unwanted defocusing due to rf pulses in the static magnetic field gradient method and for time‐dependent gradients in the rf field gradient method. Concerning the latter, a remedy is proposed which consists in applying the stronger gradient and incrementing the gradient pulse durations. After correction for relaxation, the expected value of the diffusion coefficient is retrieved. © 2010 Wiley Periodicals, Inc. Concepts Magn Reson Part A 36A: 127–137, 2010.
Analysis of electric field gradient tensors at quadrupolar nuclei in common structural motifs
Authors: Autschbach Jochen , Zheng Shaohui , Schurko Robert W. 
Published: April 2010

AbstractThis article is concerned with the analysis of electric field gradients (EFGs) using first–principles theory along with model calculations. Simple atomic orbital (AO )models for the EFG are developed in the spirit of the Townes–Dailey (TD) analysis and applied to various sets of spn hybrid orbitals and to atomic d orbital shells. These AO models are then combined with modern analysis methods rooted in first principles theory which provide accurate localized molecular orbital contributions to the EFG. It is shown by density functional computations how such analyses of the EFG for a variety of typical structural motifs can provide an intuitive way of understanding the chemical origin of the magnitude and the sign of EFG tensors at atomic nuclei, as well as of their orientation with respect to the molecular coordinate frame. The utility of graphical visualizations of EFG tensors is also emphasized. The systems that are investigated span the range from very small molecules (carbon and sulfur EFGs in CO, CS, OCS) to small‐ and medium‐sized molecules (nitrogen and aluminum EFGs in ammonia, methyl‐cyanide and ‐isocyanide, aluminum AlX3 model systems and various alumino‐organic systems), to the metal atom field gradient in transition metal complexes with Ru and Nb and a variety of ligands. © 2010 Wiley Periodicals, Inc. Concepts Magn Reson Part A 36A: 84–126, 2010.