bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mice with a deletion in the first intron of the Col1a1 gene develop dissection and rupture of aorta in the absence of aneurysms: High‐resolution magnetic resonance imaging, at 4.7 T, of the aorta and cerebral arteries
Authors: Marjamaa J. , Tulamo R. , Abo‐Ramadan U. , Hakovirta H. , Frösen J. , Rahkonen O. , Niemelä M. , Bornstein P. , Penttinen R. , Kangasniemi M. 
Published: February 2006

AbstractDeletion of the majority of the first intron of the Col1a1 gene in mice leads to decreased type I collagen synthesis and content in the aortic wall. In 54% of cases, mice homozygous for the Col1a1 mutation die of thoracic hemorrhage by the age of 18 months. It is unknown whether the fatal bleeding results from an acute dissection of the aortic wall or a gradually developing dilatation of the medial layer prior to rupture. We optimized high‐resolution MRI methods using a 4.7 T MR scanner to obtain in vivo images of the entire mouse aorta. The MR images were acquired in three imaging planes using gradient echo, spin echo, and spin echo with inversion recovery pulse sequences with a maximum in‐plane resolution of 68 × 68 μm and acquisition times less than 10 min. In five Col1a1 mutated mice aged 16 months, the MR images showed no signs of aneurysmal dilatation, wall defects, or former dissection, suggesting that the mechanism for aortic rupture is an acute dissection of the aortic medial layer. Cerebral arteries were imaged using a three‐dimensional time of fight pulse sequence. The resolution of 73 × 73 × 94 μm showed normal cerebral arteries. Histology showed a 22% thinner cerebral artery wall in Col1a1 mutated mice. Magn Reson Med, 2006. © 2006 Wiley‐Liss, Inc.
In vivo detection of brain glycine with echo‐time‐averaged 1H magnetic resonance spectroscopy at 4.0 T
Authors: Prescot Andrew P. , Frederick Blaise deB , Wang Liqun , Brown John , Jensen J. Eric , Kaufman Marc J. , Renshaw Perry F. 
Published: February 2006

AbstractA single‐voxel proton magnetic resonance spectroscopy (1H‐MRS) method is described that enables the in vivo measurement of endogenous brain glycine (Gly) levels in human subjects. At 4.0 T, TE‐averaging 1H‐MRS dramatically attenuates the overlapping myo‐inositol (mI) resonances at 3.52 ppm, permitting a more reliable measure of the Gly singlet peak. This methodology initially is described and tested in phantoms. The phantom data infers that the 3.55‐ppm peak predominantly is Gly with a smaller contribution from mI. The composite resonance thus is differentiated from pure Gly and mI and is labeled Gly*. The mI contribution was calculated as <2% of the total Gly* signal for a 1:1 mI/Gly mixture. The technique subsequently was used to acquire TE‐averaged 1H‐MRS data from the occipital cortex of healthy control subjects. The resultant spectra closely resembled experimental phantom data. LC‐model analysis provided a means for quantifying TE‐averaged 1H‐MRS spectra and a mean test–retest variability measure of 15% was established for brain Gly* levels in studies of six healthy subjects. Magn Reson Med, 2006. © 2006 Wiley‐Liss, Inc.
Analysis of residual coronary artery motion for breath hold and navigator approaches using real‐time coronary MRI
Authors: Fischer R. W. , Botnar R. M. , Nehrke K. , Boesiger P. , Manning W. J. , Peters D. C. 
Published: February 2006

AbstractCoronary artery MRI methods utilize breath holds, or diaphragmatic navigators, to compensate for respiratory motion. To increase image quality and navigator (NAV) gating efficiency, slice tracking is used, with more sophisticated affine motion models recently introduced. This study assesses the extent of remaining coronary artery motion in free breathing NAV and single and multi breath hold coronary artery MRI. Additionally, the effect of the NAV gating window size was examined. To visualize and measure the respiratory induced motion, an image containing a coronary artery cross section was acquired at each heartbeat. The amount of residual coronary artery displacement was used as a direct measure for the performance of the respiratory motion correction method. Free breathing studies with motion compensation (slice tracking with 5 mm gating window) had a similar amount of residual motion (0.76 ± 0.17 mm) as a single breath hold (0.52 ± 0.20 mm) and were superior to multiple breath holds (1.22 ± 0.60 mm). Affine NAV methods allowed for larger gating windows (∼10 mm windows) with similar residual motion (0.74 ± 0.17 mm). In this healthy adult cohort (N = 10), free‐breathing NAV methods offered respiratory motion suppression similar to a single breath hold. Magn Reson Med, 2006. © 2006 Wiley‐Liss, Inc.
Auto‐calibrated parallel spiral imaging
Authors: Heberlein and Keith , Hu Xiaoping 
Published: February 2006

AbstractThis work describes an auto‐calibrated method for parallel imaging with spiral trajectory. The method is a k‐space approach where an interpolation kernel, accounting for coil sensitivity factors, is derived from experimental data and used to interpolate the reduced data set in parallel imaging to estimate the missing k‐space data. For the case of spiral imaging, this interpolation kernel is defined along radial directions so that missing spiral interleaves can be estimated directly from neighboring interleaves. This kernel is invariant along the radial direction but varies azimuthally. Therefore, the k‐space is divided into angular sectors and sector‐specific kernels are used. It is demonstrated experimentally that relatively few sectors are sufficient for accurate reconstruction, allowing for efficient implementation. The interpolation kernels can be derived either from a separate calibration scan or self‐calibration data available with a dual‐density spiral acquisition. The reconstruction method is implemented with two sampling strategies and experimentally demonstrated to be robust. Magn Reson Med, 2006. © 2006 Wiley‐Liss, Inc.
Peripheral neuropathy in an outpatient cohort of patients with Sjögren's syndrome
Authors: Lopate Glenn , Pestronk Alan , Al‐Lozi Muhammad , Lynch Timothy , Florence Julaine , Miller Timothy , Levine Todd , Rampy Tom , Beson Brent , Ramneantu Irena 
Published: February 2006

AbstractPeripheral neuropathy is common in patients with Sjögren's syndrome (SS), but its precise prevalence is unknown. Most prior studies were conducted at neurology or rheumatology specialty clinics and likely selected for a more severely affected population. We evaluated 22 SS patients and 10 controls for evidence of neuropathy in an outpatient setting at a regional meeting of the Sjögren's Syndrome Foundation. We performed neurological examinations and nerve conduction studies (NCSs) and measured serum antinuclear antibody (ANA) and SS‐A and SS‐B antibody levels. Participants filled out a questionnaire pertaining to symptoms, diagnosis, and treatment. We found that signs and symptoms related to small axons were more common in patients with SS than in controls. Complaints of painful distal paresthesias in the feet were noted in 59% of patients but in only 10% of controls, and of abnormal sweating in 41% and 0%, respectively. Examination revealed decreased pinprick sensation in 64% of patients with SS, but in only 30% of controls. Overall, 45% of the patients but none of the controls were thought to have an isolated small‐fiber neuropathy. Large‐fiber dysfunction (as measured by testing vibration, deep tendon reflexes, and NCSs) was similar between the two groups. We conclude that small‐fiber neuropathy is common in patients with SS. Muscle Nerve 2006
Cholinergic neuromuscular hyperactivity in patients with myasthenia gravis seropositive for MuSK antibody
Authors: Punga Anna Rostedt , Flink Roland , Askmark Håkan , Stålberg Erik V. 
Published: February 2006

AbstractA 75‐year‐old man with severe oculobulbar myasthenia gravis (MG) treated with acetylcholine esterase inhibitors (AChEIs) was found to have muscle‐specific tyrosine kinase (MuSK) antibodies. Neurophysiological examination displayed extra repetitive discharges after the compound motor action potential (CMAP) at low‐frequency stimulation, possibly triggered by AChEI. This indicates an abnormal sensitivity to acetylcholine in patients with MuSK antibodies and may be a useful indicator of the adverse effect of AChEI treatment in these patients. Muscle Nerve, 2006
Axonal function and activity‐dependent excitability changes in myotonic dystrophy
Authors: Krishnan Arun V. , Kiernan Matthew C. 
Published: February 2006

AbstractTo investigate peripheral nerve function and its potential contribution to symptoms of weakness in myotonic dystrophy type 1 (MD), nerve excitability was assessed in 12 MD patients. Compound muscle action potentials (CMAPs) were recorded at rest from abductor pollicis brevis (APB) following stimulation of the median nerve. Stimulus–response behavior, threshold electrotonus, a current–threshold relationship, and recovery cycles were successfully recorded in each patient. Compared with controls, there was significant reduction in CMAP amplitude in MD patients. This was accompanied by reduction in depolarizing threshold electrotonus and an increase in refractoriness and in the duration of the relative refractory period. To determine whether alteration in axonal resting membrane potential was a factor underlying these changes, axonal excitability was assessed following maximal contraction of APB for 60 seconds. Following contraction, there was reduction in CMAP amplitude for a submaximal stimulus (by 51.5 ± 11.8%) and an increase in superexcitability (of 22.2 ± 12.0%), consistent with activity‐dependent hyperpolarization, with a greater increase in threshold for MD patients compared to controls (MD group, 22.3 ± 5.1%; controls, 11.7 ± 2.1%; P < 0.04) and prolonged recovery to baseline. The present study has established that greater activity‐dependent changes in excitability may be induced in MD patients by maximal voluntary contraction when compared to controls. The excitability changes and prolonged recovery of threshold following contraction are likely to contribute to symptoms of fatigue and weakness in MD patients. Muscle Nerve, 2006
Lewis–Sumner syndrome in hepatitis C virus infection: A possible pathogenetic association with therapeutic problems
Authors: Caporale Christina M. , Capasso Margherita , Ragno Michele , Muzio Antonio Di , Uncini Antonino 
Published: February 2006

AbstractA patient with chronic hepatitis from hepatitis C virus (HCV) infection developed Lewis–Sumner syndrome (LSS). The neuropathy worsened after intravenous immunoglobulins, remitted after intravenous methylprednisolone, relapsed during interferon‐α, but responded again to steroids continued for 68 weeks with clinical remission and without worsening of hepatitis. We are not aware of other reports of HCV infection and LSS. This association may be coincidental or related to a virus‐triggered immune‐mediated process. Although the coexistence of a dysimmune neuropathy with hepatitis makes problematic the choice of treatment, we emphasize that the patient's condition during treatment with steroids and the 46 following weeks without therapy has been excellent. Muscle Nerve, 2006
Mortality experiences among 15+ year survivors of childhood and adolescent cancers
Authors: Lawless Shauna C.W. , Verma Puja , Green Daniel M. , Mahoney Martin C. 
Published: February 2006

AbstractBackgroundStudies of childhood and adolescent cancer survivorship have tended to focus on limited survival intervals (e.g., 5 and 10 years). Our report evaluates gender‐specific overall mortality, as well as mortality by age group, and by cause, among 15+ year survivors of cancer diagnosed during childhood or adolescence.ProcedureThis was a retrospective cohort study of 565 15+ year childhood cancer survivors from Roswell Park Cancer Institute's Long‐Term Follow‐Up Project. Sex‐ and age‐specific person‐years at risk were accumulated and applied to age‐specific mortality rates for New York State, excluding New York City. Standardized mortality ratios (SMRs), and 95% confidence intervals, were calculated and compared to mortality risks of the general population.ResultsSecond malignancy was the leading cause of death among male and female survivors (15/38 deaths, 39%). Excess overall mortality was noted among both males (SMR = 284) and females (SMR = 371). Significant mortality excesses were seen in both genders for deaths due to primary malignant neoplasms and secondary malignancies, as well as cardiac deaths among males. Excess mortality was noted across most age strata. In the scenario of no cancer relapse, overall mortality in both genders did not differ significantly from the general population.ConclusionsLong‐term survivors of childhood and adolescent cancers continue to demonstrate significant excess mortality. However, overall mortality among 15+ year survivors without a relapse appears to be comparable to the general population. The leading cause of death among 15+ year survivors is second malignancy in this study, which represents a novel and important finding in terms of long‐term follow‐up. Pediatr Blood Cancer 2007;48:333–338. © 2006 Wiley‐Liss, Inc.
Radiotherapy for life‐threatening mediastinal hemangioma with Kasabach–Merritt syndrome
Authors: Kwok‐Williams Michelle , Perez Zuleima , Squire Roly , Glaser Adam , Bew Stephanie , Taylor Roger 
Published: February 2006

AbstractKasabach–Merritt Syndrome (KMS) originally referred to a hemangioma associated with life‐threatening thrombocytopenia and a consumption coagulopathy. Treatment includes surgery, steroids, and alpha interferon. However response may be unsatisfactory and mortality rates of 10–37% have been reported. We report a case of a 4‐month‐old male whose disease had not responded to steroids and alpha interferon. He required ventilation, and his condition was deteriorating. It was thought that he would probably die of his condition. He was treated with 9 Gy in three fractions weekly of radiotherapy (RT). Clinical response was good and he is well and free from progression 4 years and 7 months after RT. A review of the literature on the role of RT in the management of hemangiomas is presented. Pediatr Blood Cancer 2007;49:739–744. © 2006 Wiley‐Liss, Inc.
Novel acyclic nitroxides for nitroxide‐mediated polymerization: Kinetic, electron paramagnetic resonance spectroscopic, X‐ray diffraction, and molecular modeling investigations
Authors: Lagrille Olivier , Cameron Neil R. , Lovell Peter A. , Blanchard Robert , Goeta Andrés E. , Koch Rainer 
Published: February 2006

AbstractThis work describes the synthesis of new hydrophobic acyclic nitroxides [derived from 2,2,5‐trimethyl‐4‐phenyl‐3‐azahexane‐3‐nitroxide (TIPNO)] designed to be employed in radical miniemulsion polymerization. We present the synthetic strategies employed to obtain these different nitroxides and the determination of certain important parameters, such as the dissociation rate constant, the combination rate constant, and the decomposition rate constant, of the corresponding alkoxyamines. All these new nitroxides give good control of the bulk radical polymerization of styrene in comparison with the parent TIPNO. The molecular structure of some nitroxides presented herein has been elucidated by single‐crystal X‐ray diffraction, and their structural determination helps us to understand better the influence of the nitroxide structure on the activation energy. A molecular modeling study has also been conducted on these new nitroxides, and a good linear correlation between the activation energy and the CNC bond angle for a series of nitroxides with the same type of leaving radical has been found. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 1926–1940, 2006
Atom transfer radical copolymerization of acrylonitrile and ethyl methacrylate at ambient temperature
Authors: Brar A. S. , Saini Tripta 
Published: February 2006

AbstractCopolymerization of acrylonitrile (AN) and ethyl methacrylate (EMA) using copper‐based atom transfer radical polymerization (ATRP) at ambient temperature (30 °C) using various initiators has been investigated with the aim of achieving control over molecular weight distribution. The effect of variation of concentration of the initiator, ligand, catalyst, and temperature on the molecular weight distribution and kinetics were investigated. No polymerization at ambient temperature was observed with N,N,N′,N′,N″‐pentamethyldiethylenetriamine (PMDETA) ligand. The rate of polymerization exhibited 0.86 order dependence with respect to 2‐bromopropionitrile (BPN) initiator. The first‐order kinetics was observed using BPN as initiator, while curvature in first‐order kinetic plot was obtained for ethyl 2‐bromoisobutyrate (EBiB) and methyl 2‐bromopropionate (MBP), indicating that termination was taking place. Successful polymerization was also achieved with catalyst concentrations of 25 and 10% relative to initiator without loss of control over polymerization. The optimum [bpy]0/[CuBr]0 molar ratio for the copolymerization of AN and EMA through ATRP was found to be 3/1. For three different in‐feed ratios, the variation of copolymer composition (FAN) with conversion indicated toward the synthesis of copolymers having slight changes in composition with conversion. The high chain‐end functionality of the synthesized AN‐EMA copolymers was verified by further chain extension with methyl acrylate and styrene. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 1975–1984, 2006
Preparation of linear α‐olefins to high‐molecular weight polyethylenes using cationic α‐diimine nickel(II) complexes containing chloro‐substituted ligands
Authors: Song Chun‐Lei , Tang Li‐Ming , Li Yan‐Guo , li Xiao‐Fang , Chen Jie , Li Yue‐Sheng 
Published: February 2006

AbstractA series of α‐diimine nickel(II) complexes containing chloro‐substituted ligands, [(Ar)NC(C10H6)CN(Ar)]NiBr2 (4a, Ar = 2,3‐C6H3Cl2; 4b, Ar = 2,4‐C6H3Cl2; 4c, Ar = 2,5‐C6H3Cl2; 4d, Ar = 2,6‐C6H3Cl2; 4e, Ar = 2,4,6‐C6H2Cl3) and [(Ar)NC(C10H6)CN(Ar)]2NiBr2 (5a, Ar = 2,3‐C6H3Cl2; 5b, Ar = 2,4‐C6H3Cl2; 5c, Ar = 2,5‐C6H3Cl2), have been synthesized and investigated as precatalysts for ethylene polymerization. In the presence of modified methylaluminoxane (MMAO) as a cocatalyst, these complexes are highly effective catalysts for the oligomerization or polymerization of ethylene under mild conditions. The catalyst activity and the properties of the products were strongly affected by the aryl‐substituents of the ligands used. Depending on the catalyst structure, it is possible to obtain the products ranging from linear α‐olefins to high‐molecular weight polyethylenes. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 1964–1974, 2006
Graft polymerization of vinyl monomers inside macroporous polyacrylamide gel, cryogel, in aqueous and aqueous‐organic media initiated by diperiodatocuprate(III) complexes
Authors: Savina Irina N. , Mattiasson Bo , Galaev Igor Yu. 
Published: February 2006

AbstractGraft polymerization initiated by diperiodatocuprate(III) complex (Cu(III)) initiator was found to be an effective and convenient method for graft polymerization of vinyl monomers onto macroporous polyacrylamide gels, the so‐called cryogels (pAAm‐cryogels). The effect of time, temperature, monomer and initiator concentration during the graft polymerization in aqueous and aqueous‐organic media was studied. The graft polymerization of water‐soluble monomers as [2‐(methacryloyloxy)ethyl]‐trimethylammonium chloride, 2‐hydroxyethyl methacrylate, N‐isopropylacrylamide, and N,N‐dimethylacrylamide proceeds with higher grafting yield in aqueous medium, as compared with that in aqueous‐organic media. Graft polymerization in aqueous‐organic media such as water–DMSO solutions allows grafting of water‐insoluble monomers such as glycidyl methacrylate and N‐tert‐butylacrylamide with high grafting degrees of 100 and 410%, respectively. It was found that the deposition of initiator on the pore surface of cryogels promoted graft polymerization by facilitating the formation of the redox couple Cu(III)‐acrylamide group. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 1952–1963, 2006
Synthesis and characterization of block copolymers by metal‐ and solvent‐free ring‐opening polymerization of cyclic carbonates initiated from PEG‐based surfactants
Authors: Morinaga Hisatoyo , Ochiai Bungo , Mori Hideharu , Endo Takeshi 
Published: February 2006

AbstractRing‐opening polymerizations of trimethylene carbonate (TC) and 2,2‐dimethyltrimethylene carbonate (DTC) are initiated from hydroxyl‐terminated polyethylene glycol (PEG) and PEG‐based surfactants (Triton X‐100 or Triton X‐405) in the absence of any catalysts. The metal‐ and solvent‐free polymerizations proceed under melt at 150 °C, affording Triton X‐100‐block‐poly(TC) with Mn of 1400–5200 and Triton X‐100‐block‐poly(DTC) with Mn of 1800–7100 in excellent yields. The molecular weights and the comonomer composition of the resulting copolymers are controlled by the feed ratios of the monomers to the initiators, confirmed by gel permeation chromatography and 1H NMR spectroscopy. The solubilities of the block copolymers composed of hydrophilic PEG segment and hydrophobic poly(TC) or poly(DTC) segment depend on both the compositions and the components. For example, Triton X‐100‐block‐poly (TC) (TC/EG = 9.5/9.5) and Triton X‐405‐block‐poly(TC) (TC/EG = 28/40, 46/40) milky suspend in water, while Triton X‐405‐block‐poly(TC) (TC/EG = 9.7/40) dissolves in water. A dynamic light scattering study reveals that the particle distribution of a copolymer, Triton X‐405‐block‐poly(TC) (TC/EG = 9.7/40) in water, has a monodisperse unimodal pattern ranging from 92 to 368 nm. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 1985–1996, 2006
Solubilizing single‐walled carbon nanotubes with pyrene‐functionalized block copolymers
Authors: Bahun Greg J. , Wang Clair , Adronov Alex 
Published: February 2006

AbstractThe effect of pyrene distribution within pyrene‐functionalized random and block copolymers on noncovalent polymer/single‐walled carbon nanotube (SWNT) interactions was investigated. The block copolymers served as superior solubilizing agents in comparison with the random copolymers. Also, increasing the pyrene content within a polymer, while a constant molecular weight was maintained, improved SWNT solubility and therefore had to result in stronger polymer–nanotube interactions. However, increasing the length of the pyrene‐containing block diminished nanotube solubility, likely because of a lower number of polymer chains that were capable of binding to the nanotube surface. Atomic force microscopy and transmission electron microscopy indicated that the polymer–SWNT interactions were capable of partially debundling the nanotubes into individual solvated structures. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 1941–1951, 2006