bluuebunny/crossref_metadata_2025_split huggingface dataset:
Feedback Inhibition of Leptin Receptor/Jak2 Signaling via Tyr1138 of the Leptin Receptor and Suppressor of Cytokine Signaling 3
Authors: Dunn Sarah L. , Björnholm Marie , Bates Sarah H. , Chen Zhibin , Seifert Matthew , Myers Martin G. 
Published: December 2004

Abstract
Leptin is an adipocyte-derived hormone that communicates the status of body energy stores to the brain to regulate feeding and energy balance. The inability of elevated leptin levels to adequately suppress feeding in obesity suggests attenuation of leptin action under these conditions; the activation of feedback circuits due to high leptin levels could contribute to this leptin resistance. Using cultured cells exogenously expressing the long form of the leptin receptor (LRb) or an erythropoietin receptor/LRb chimera, we show that chronic stimulation results in the attenuation of LRb signaling and the establishment of a state in which the receptor is refractory to reactivation. Mutation of LRb Tyr1138 (the site that recruits signal transducer and activator of transcription 3) alleviated this feedback inhibition, suggesting that signal transducer and activator of transcription 3 mediates the induction of a feedback inhibitor, such as suppressor of cytokine signaling 3 (SOCS3), during chronic LRb stimulation. Indeed, manipulation of the expression or activity of the LRb-binding tyrosine phosphatase, SH2-domain containing phosphatase-2, by overexpression of wild-type and dominant negative isoforms or RNA interference-mediated knockdown did not alter the attenuation of LRb signals. In contrast, SOCS3 overexpression repressed LRb signaling, whereas RNA interference-mediated knockdown of SOCS3 resulted in increased LRb signaling that was not attenuated during chronic ligand stimulation. These data suggest that Tyr1138 of LRb and SOCS3 represent major effector pathways for the feedback inhibition of LRb signaling. Furthermore, we show that mice expressing an LRb isoform mutant for Tyr1138 display increased activity of the leptin-dependent growth and immune axes, suggesting that Tyr1138-mediated feedback inhibition may regulate leptin sensitivity in vivo.
Associating a time‐based prospective memory task with an expected context can improve or impair intention completion
Authors: Cook Gabriel I. , Marsh Richard L. , Hicks Jason L. 
Published: December 2004

AbstractThree experiments investigated time‐based prospective memory defined here as remembering to fulfil an intention during a later window of time. When people associated the response window with a future context, time‐based responding was better if that context expectation was correct as compared with having no context expectation at all. By contrast, if the response window occurred in a context that preceded the expected context, time‐based performance was worse than having no context expectation at all. An explicit reminder about the intention was sufficient to ameliorate the decrement found with an incorrect context association. However, successfully completing a different, event‐based prospective memory intention was not sufficient to overcome the incorrect context association. The authors assert that possessing such associations alters normal monitoring of the passage of time which in turn leads to the pattern of results obtained. Copyright © 2004 John Wiley & Sons, Ltd.
The effect of overlearning on long‐term retention
Authors: Rohrer Doug , Taylor Kelli , Pashler Harold , Wixted John T. , Cepeda Nicholas J. 
Published: December 2004

AbstractOnce material has been learned to a criterion of one perfect trial, further study within the same session constitutes overlearning. Although overlearning is a popular learning strategy, its effect on long‐term retention is unclear. In two experiments presented here, 218 college students learned geography facts (Experiment 1) or word definitions (Experiment 2). The degree of learning was manipulated and measured via multiple test‐with‐feedback trials, and participants returned for a final cued recall test between 1 and 9 weeks later. The overlearners recalled far more than the low learners at the 1‐week test, but this difference decreased dramatically thereafter. These data suggest that overlearning (and its concomitant demand for additional study time) is an inefficient strategy for learning material for meaningfully long periods of time. Copyright © 2004 John Wiley & Sons, Ltd.
Gain scheduling control of functional electrical stimulation for assisted standing up and sitting down in paraplegia: a simulation study
Authors: Previdi Fabio , Ferrarin Maurizio , Savaresi Sergio M. , Bittanti Sergio 
Published: December 2004

AbstractThis paper reports on a simulation study that concerns the design of a non‐linear controller for the standing up and the sitting down of a paraplegic patient by means of functional electrical stimulation. The simulations refer to a specific experimental device developed at the Fondazione Don Gnocchi (Italy). This is a seesaw, with the patient on one side and a weight on the other side. The patient is seated so that its posture can be fully known in real‐time by continuously monitoring the knee joint angle. By delivering a suitable electrical stimulation to the quadriceps muscles groups, the patient can be raised and made to sit via smooth movements. Hitherto, the only feedback control law, which has been implemented in this area, is based on a PID controller and usually provides poor tracking performances. Hence, in this work, a non‐linear gain scheduling controller has been designed and tested in a series of simulation experiments. The controller is tuned following a gain scheduling strategy: a set of local linear quadratic controllers is designed using a set of linear tangent models. A global non‐linear gain scheduled controller is then obtained via interpolation. The gain‐ scheduled controller is implemented following an advanced strategy that guarantees that the so‐called linearization property holds. Copyright © 2004 John Wiley & Sons, Ltd.
Liquid residence time distribution in the film flow monolith reactor
Authors: Heibel Achim K. , Lebens Paul J. M. , Middelhoff Jack W. , Kapteijn Freek , Moulijn Jacob 
Published: December 2004

AbstractAn experimental method and data analysis procedure are introduced to determine the liquid residence time distribution (RTD) of monoliths based on the imperfect pulse injection of a dye tracer. Repeatable experiments for two different lengths allowed for the deconvolution of the RTD function of a 375‐mm‐long monolith section with 3.64‐mm2 channels out of dense ceramic material. The experimentally determined liquid saturations are in fair agreement with the predictions of computational fluid dynamics (CFD) calculations, assuming uniform corner flow in the square channels. The laminar film flow results in strong tailing of the RTD curves and large reduced standard deviation values. Despite the reasonable agreement for the mean residence time the CFD model based on uniform liquid distribution over the monolith channels and the individual channel corners failed to describe the experimentally determined reduced RTD curves. Applying a measured corner‐scale liquid distribution pattern in combination with the CFD model resulted in good agreement with the experiments. Furthermore, this approach also improved the agreement between measurement and model for the mean residence time. © 2004 American Institute of Chemical Engineers AIChE J, 51: 122–133, 2005
Neonatal phenotype in Kabuki syndrome
Authors: Vaux Keith K. , Hudgins Louanne , Bird Lynne M. , Roeder Elizabeth , Curry Cynthia J.R. , Jones Marilyn , Jones Kenneth L. 
Published: December 2004

AbstractThe Kabuki syndrome is a well‐established pattern of human malformation with readily recognizable features, however the diagnosis is rarely made in the newborn period. The purpose of this study was to determine if there exists a neonatal phenotype for this disorder. We ascertained 16 infants evaluated in the first 28 days of life by a dysmorphologist who subsequently received the diagnosis of Kabuki syndrome. The average age of initial evaluation was 8 days and the average age of diagnosis was 2 years 6 months. Based on these findings, it is suggested that the distinctive clinical phenotype seen in older patients is also evident in the newborn period. Published 2004 Wiley‐Liss, Inc.
Improvement of the production of GFPuv‐β1,3‐N‐acetylglucosaminyltransferase 2 fusion protein using a molecular chaperone‐assisted insect‐cell‐based expression system
Authors: Kato Tatsuya , Murata Takeomi , Usui Taichi , Park Enoch Y. 
Published: December 2004

AbstractA stable Tn‐5B1‐4 insect cell line co‐expressing the recombinant GFPuv‐β1,3‐N‐acetylglucosaminyltransferase 2 (GFPuv‐β3GnT2) protein fused to a melittin signal sequence with a lectin‐like molecular chaperone, human calnexin (hCNX) or human calreticulin (hCRT), was constructed. The expression of either of these molecular chaperones is under the control of a weak promoter, OpMNPV IE2, while that of GFPuv‐β3GnT2 is under the control of Bombyx mori actin promoter. This co‐expression system was compared between two different insect cell–baculovirus expression systems: (1) co‐infection of the recombinant baculovirus containing a molecular chaperone (AcNPV‐hCNX or ‐hCRT) with a recombinant baculovirus containing GFPuv‐β3GnT2 fused with the melittin signal sequence (AcNPV‐me‐GGT); (2) infection of AcNPV‐me‐GGT to a stably expressing cell line for either hCNX or hCRT. In the co‐infection system, the intracellular GFPuv‐β3GnT2 expression level was low because of the improved secretion level ratio of the fusion protein, due to the chaperone expression. In the case of infection to the stably expressing cell line for a chaperone, the extracellular GFPuv‐β3GnT2 expression level was similar to the intracellular expression level. This suggests that the amount of expressed chaperone is not sufficient to process β3GnT2. On the other hand, the co‐expression system produced an extracellular β3GnT activity of 22–23 mU/mL, which was approximately 3.5‐ and 11‐fold higher than those of the stable expression of the fusion gene without the chaperone and the conventional BES with the addition of protease, respectively. The secretion level ratio of the fusion protein of this system increased to 82%, which was approximately 1.5‐fold that of any other expression system investigated thus far. These results indicate that the ratio of the expression level of the target gene to that of the chaperone gene may be an important factor in maximizing the production of a target protein. The molecular‐chaperone‐assisted expression system using a stably transformed insect cell line offers promising prospects for the efficient production of recombinant secretory proteins in insect cells. © 2004 Wiley Periodicals, Inc.
Baculovirus as a highly efficient gene delivery vector for the expression of hepatitis delta virus antigens in mammalian cells
Authors: Wang Kuei‐Chun , Wu Jaw‐Chin , Chung Yao‐Chi , Ho Yi‐Chen , Dah‐Tsyr Chang Margaret , Hu Yu‐Chen 
Published: December 2004

AbstractBaculovirus has been employed for a wide variety of applications. In this study, we further expanded the application to the high‐level expression of hepatitis delta virus (HDV) antigens and the formation of virus‐like particles (VLP) in transduced mammalian cells. To this end, two recombinant baculoviruses were constructed to express large hepatitis delta antigen (L‐HDAg) and hepatitis B surface antigen (HBsAg) under mammalian promoters. With a simplified transduction protocol using unconcentrated virus, high transduction efficiencies were achieved in hepatoma cells, in which L‐HDAg and HBsAg were expressed abundantly, allowing for easy colorimetric detection in Western blots. L‐HDAg alone was nucleus‐bound and HBsAg alone was secreted; formation and secretion of HDV‐like particles were readily detected upon coexpression, indicating that the baculovirus‐expressed proteins were processed correctly as the authentic proteins. Quantitative real‐time PCR (Q‐PCR) analyses quantitatively revealed that baculovirus transduction was more efficient than plasmid transfection with respect to DNA uptake and DNA transport to the nucleus. Furthermore, superinfection introduced more baculovirus DNA into cells in the long‐term culture as revealed by Q‐PCR, thereby enhancing and prolonging the expression. In summary, baculovirus transduction can be an attractive method as an alternative to the plasmid transfection commonly employed for HDV research thanks to the significantly higher gene delivery efficiencies as well as the abundant expression and proper processing. Baculovirus can also be envisaged as a useful tool for investigating protein–cell interactions and virus assembly. © 2004 Wiley Periodicals, Inc.
Effective follow-up for recurrence or a second primary cancer in patients with early gastric cancer
Authors: Ikeda Y , Saku M , Kishihara F , Maehara Y 
Published: December 2004

Abstract

Background
Patients with early gastric cancer have an excellent prognosis with low rates of recurrence, but may have an increased risk of developing a second primary cancer. Because the number of early gastric cancers has increased, clarification of both recurrences and second primary cancers is important for the development of effective postoperative follow-up programmes.

Methods
Data on 1070 patients with early gastric cancer were analysed retrospectively with respect to the clinicopathological features of both recurrence and second primary cancers after surgical treatment.

Results
Multivariate analysis showed that lymph node metastasis and older age were independent risk factors for recurrence of early gastric cancer. The incidence of second primary cancers was 5·0 per cent; lung and colorectal cancers were detected most frequently, followed by cancers in the oesophagus, breast and remnant stomach.

Conclusion
Clinicopathological features of patients with early gastric cancer can be used to identify those most at risk of developing either recurrence or a second primary cancer.
Major urinary dysfunction after mesorectal excision for rectal carcinoma
Authors: Kneist W , Heintz A , Junginger T 
Published: December 2004

Abstract

Background
Urinary dysfunction may occur after mesorectal excision and pelvic autonomic nerve preservation (PANP) in patients with rectal carcinoma. The aim of this prospective study was to identify factors predictive of long-term urinary catheterization.

Methods
Two hundred and ten patients without significant urological problems underwent resection of rectal cancer with mesorectal excision. The number of patients with complete, partial or no identification of the nerves was documented and correlated with possible predictive factors for postoperative major urinary dysfunction.

Results
Eight patients (3·8 per cent) required long-term urinary catheterization: two after complete PANP (two of 168) and six in whom PANP was incomplete (six of 42) (P = 0·001). Multiple regression analysis identified incomplete PANP (odds ratio 13·8 (95 per cent confidence interval 2·7 to 71·3); P = 0·002) as a predictive factor for major urinary dysfunction.

Conclusion
Major urinary dysfunction after mesorectal excision for rectal cancer is associated with an incomplete nerve-sparing technique.
Multipoint Recognition of Catecholamines by Hydrindacene‐Based Receptors Accompanied by the Complexation‐Induced Conformational Switching
Authors: Kawai Hidetoshi , Katoono Ryo , Fujiwara Kenshu , Tsuji Takashi , Suzuki Takanori 
Published: December 2004

AbstractThe molecular recognition of catecholamines by hydrindacene‐based receptors 1 and 2, as well as the durene‐based receptor 3, and the guest‐induced conformational changes are reported. These receptors selectively bind adrenaline and dopamine salts through the guests' ammonium group and 3‐hydroxyl group on the aromatic ring. In the case of adrenaline, an additional hydrogen bond with a benzylic hydroxyl group is formed. In 2 % CD3CN/CDCl3, the association constants are of the order of 104 M−1, which is much larger than with guests without the 3‐hydroxyl groups (103 M−1). The two amide groups of receptor 1 can rotate freely around the CaromaticCamide bond, whereas the tert‐amide in 2 changes between two stable conformations at a slow enough rate to allow detection by 1H NMR spectroscopy. In the absence of a guest molecule, the syn‐conformer is less stable than the anti‐conformer. On complex formation with adrenaline, the syn‐conformer becomes dominant due to an intramolecular dipole‐reversal effect in addition to multipoint hydrogen bonding.
Outer‐Sphere Hydration and Liquid−Liquid Partition of Metal(III) Chelates − Density Functional Calculations
Authors: Czerwiński Marian , Narbutt Jerzy 
Published: December 2004

AbstractHydration of two coordinatively saturated metal chelates, tris(propane‐1,3‐dionato)scandium(III) and tris(propane‐1,3‐dionato)cobalt(III), was studied theoretically using the density functional method with a three‐parameter B3LYP implementation at different variants for calculating the hydration energy, including corrections for ZPVE, BSSE, polarisation functions, temperature and the number of hydrating water molecules in the system. Formation of hydrates was demonstrated, with water hydrogen‐bonded to ligands (outer‐sphere hydration). After corrections for side effects, good correlations were found between the energy and the length of these hydrogen bonds in the hydrates of both chelates. Also, the calculated changes in charge distribution on the atoms of hydrogen‐bonded water in these model chelates qualitatively agree with the experimental 1H NMR spectroscopic data for the analogous tris(pentane‐2,4‐dionato)cobalt(III) species. An implicit solvation model (SCI‐PCM) was used to take into account solvent effects of water and heptane on the energies of the model chelates studied and to calculate their enthalpies of transfer from heptane to water. In spite of simplifications in the model, satisfactory agreement was found between the calculated values and the experimental standard enthalpies of transfer of the analogous chelates, namely the tris(pentane‐2,4‐dionates) of scandium and cobalt(III). (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Tetracyanoquinodimethanido Derivatives of (Terpyridine)‐ and (Phenanthroline)metal Complexes − Structural and Magnetic Studies of Radical‐Ion Salts
Authors: Alonso Cristina , Ballester Loreto , Gutiérrez Angel , Perpiñán M. Felisa , Sánchez Ana E. , Azcondo M. Teresa 
Published: December 2004

AbstractSeveral derivatives of formulae [M(terpy)2](TCNQ)2 or [M(terpy)2](TCNQ)3 (M = Ni, Cu, Zn; terpy = 2,2′:6′,2"‐terpyridine; TCNQ= 7,7,8,8‐tetracyanoquinodimethane) and [M(phen)3](TCNQ)2 or [M(phen)3](TCNQ)4 (M = Fe, Ni; phen = 1,10‐phenanthroline) have been obtained. The crystal structures of [M(terpy)2](TCNQ)2 (M = Ni, Cu) show that the metal is surrounded by the terpyridine nitrogen atoms in a closed octahedral environment and the TCNQ anions are dimerised by π overlap. The cationic [M(terpy)2]2+ and the anionic [TCNQ]22− groups alternate in the crystal. For the derivatives with three TCNQ groups, the existence of a stack of trimeric [TCNQ]32− ions having electronic delocalisation is proposed. The compound [Fe(phen)3](TCNQ)2, which shows a strong interaction between TCNQ anions, led to the formation of a σ bond in the diamagnetic species [TCNQ−TCNQ], while the nickel analogue is expected to have a localised structure formed by alternation of cationic metal complexes and dimeric [TCNQ]22− anions similar to those observed in the analogous terpy derivatives. The derivatives having four TCNQ groups also show electronic delocalisation and a 1D stack based on the magnetic data is proposed. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Gold(0) and Gold(III) Reactivity towards the Tetraphenyldithioimidodiphosphinic Acid, [Ph2P(S)NHP(S)Ph2]
Authors: Abbati G. Luca , Aragoni M. Carla , Arca Massimiliano , Carrea M. Bonaria , Devillanova Francesco A. , Garau Alessandra , Isaia Francesco , Lippolis Vito , Marcelli Marco , Silvestru Cristian , Verani Gaetano 
Published: December 2004

AbstractThe reaction of gold powder with the iodine adduct of Ph2P(S)NHP(S)Ph2 (HL) in Et2O gave the complex [Au(L)I2] under mild reaction conditions. Its crystal structure is comprised of discrete, monomeric molecules with a central AuIII ion bonded to two sulfur atoms by an anionic ligand L and two iodide anions in a slightly distorted square‐planar coordination geometry. From the reaction of [AuCl3(tht)] with HL in CH2Cl2 it is possible, besides the main complex [Au(L)]2, to separate the neutral AuI complex [Au(L′2H)], L′ = [Ph2P(S)NP(O)Ph2]−, the crystal structure of which features a AuI ion linearly coordinated to two sulfur atoms and a proton bridging two oxygen atoms of the PO groups. 31P NMR CP MAS spectroscopy is in accordance with the nature of the ligands in the complex. The reaction chemistry of [Au(L′2H)] in CH2Cl2 towards the acid CF3COOH and the organic base 1,8‐bis(dimethylamino)naphthalene is reported. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Sonochemical Reaction of [Fe(CO)5] with 1‐Methylimidazole in An Ionic Liquid: Formation of [(1‐Methylimidazole)6FeII](PF6)2
Authors: Jacob David S. , Kahlenberg Volker , Wurst Klaus , Solovyov Leonid A. , Felner Israel , Shimon Linda , Gottlieb Hugo E. , Gedanken Aharon 
Published: December 2004

AbstractThe ionic liquid 1‐butyl‐3‐methylimidazolium hexafluorophosphate, (BMI+)(PF6−), has been used as a solvent in the sonochemical reaction of 1‐methylimidazole and [Fe(CO)5] at 40−50 °C under air. The reaction afforded [(1‐methylimidazole)6FeII](PF6)2, the structure of which was determined at 293 K by single‐crystal X‐ray diffraction methods. The salt crystallizes in the trigonal space group P$\bar 3$
with unit‐cell parameters of a = 11.4603(16) Å, c = 8.0172(11) Å, and Z = 1. The crystals showed twinning by merohedry, which was accounted for in the structure determination and refinement calculations. All the 1‐methylimidazole ligands are equivalent, with a Fe−N bond length of 2.204(3) Å. Mössbauer spectroscopy confirmed the presence of Fe2+. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)