bluuebunny/crossref_metadata_2025_split huggingface dataset:
BMP‐induced L‐Maf regulates subsequent BMP‐independent differentiation of primary lens fibre cells
Authors: Pandit Tanushree , Jidigam Vijay K. , Gunhaga Lena 
Published: July 2011

AbstractBone morphogenetic protein (BMP) signals are essential for lens development. However, the temporal requirement of BMP activity during early events of lens development has remained elusive. To investigate this question, we have used gain‐ and loss‐of‐function analyses in chick explant and intact embryo assays. Here, we show that BMP activity is both required and sufficient to induce L‐Maf expression, whereas the onset of δ‐crystallin and initial elongation of primary lens fibre cells are BMP‐independent. Moreover, before lens placode formation and L‐Maf onset, but not after, prospective lens placodal cells can switch to an olfactory placodal fate in response to decreased BMP activity. In addition, L‐Maf is sufficient to up‐regulate δ‐crystallin independent of BMP signals. Taken together, these results show that before L‐Maf induction BMP activity is required for lens specification, whereas after L‐Maf up‐regulation, the early differentiation of primary lens fibre cells occurs independent of BMP signals. Developmental Dynamics 240:1917–1928, 2011. © 2011 Wiley‐Liss, Inc.
Characterization of three synuclein genes in Xenopus laevis
Authors: Wang Chengdong , Liu Yao , Chan Wood Yee , Chan Sun On , Grunz Horst , Zhao Hui 
Published: July 2011

AbstractThe synuclein family consists of three small intracellular proteins mainly expressed in neural tissues, and has been associated with human neurodegenerative diseases. We have examined the spatial and temporal expression patterns of three synuclein genes during embryogenesis of Xenopus laevis. The Xenopus synucleins were firstly expressed in the developing nervous system at the tail bud stages. At tadpole stages, Xenopus snca was expressed in the brain, branchial arch and somite, and sncbb signals were detected in entire brain and spinal cord. However, sncg was only expressed in the peripheral nervous system including trigeminal nerve and dorsal root ganglion. RT‐PCR indicated that expression of synucleins was up‐regulated at the end of neurulation, and then maintained at later examined stages. Our study provides the spatiotemporal expression patterns of the synuclein family genes in Xenopus embryos, and forms a basis for further functional analysis of synucleins. Developmental Dynamics 240:2028–2033, 2011. © 2011 Wiley‐Liss, Inc.
PCP effector proteins inturned and fuzzy play nonredundant roles in the patterning but not convergent extension of mammalian neural tube
Authors: Heydeck Westley , Liu Aimin 
Published: July 2011

AbstractPCP effector proteins Inturned (Intu) and Fuzzy (Fuz) play important roles in mammalian neural development and ciliogenesis, but the developmental defects in Intu and Fuz mutants are not the same as those with the complete loss of cilia. Furthermore, it remains unclear whether mouse Intu and Fuz play a role in convergent extension, a process regulated by PCP signaling. In the current study, we show that the functions of both Intu and Fuz in neural tube patterning are dependent on the presence of cilia. We further show that neither gene exhibits obvious genetic interaction with the core PCP regulator Vangl2 in convergent extension or patterning of the neural tube. Finally, we show in Intu; Fuz double mutants that the lack of convergent extension and more severe patterning defects in Intu and Fuz mutants does not result from a functional redundancy between these two proteins. Developmental Dynamics 240:1938–1948, 2011. © 2011 Wiley‐Liss, Inc.
Reactivity of Tris(1‐pyrazolyl)methane Towards Ru0 Complexes
Authors: Guelfi Massimo , Calucci Lucia , Forte Claudia , Pertici Paolo , Denti Gianfranco 
Published: July 2011

AbstractBy treating tris(1‐pyrazolyl)methane (tpm) with suitably activated [Ru(cod)(cot)] and [Ru(cod)(nap)] (cod = η4‐cycloocta‐1,5‐diene, cot = η6‐cycloocta‐1,3,5‐triene, nap = η6‐naphthalene) the (hydrido)RuII species [Ru(N2,N2′,C5″‐tpm)(cod)H] with cyclometalated tpm was obtained. This complex reacted with chloroform at room temperature to give [Ru(N2,N2′,C5″‐tpm)(cod)Cl] and dichloromethane. The coordination and symmetry of the novel complexes were elucidated by 1H and 13C NMR spectroscopy.
Chemoselective Rh‐Catalyzed Allylic Alkylations of Chelated Enolates using Dienylcarbonates
Authors: Hähn Saskia , Kazmaier Uli 
Published: July 2011

AbstractWilkinson's catalyst, RhCl(PPh3)3, was found to be an excellent catalyst not only for highly regio‐ but also chemoselective allylic alkylations of chelated enolates. In contrast to Pd‐catalyzed reactions, the Rh‐catalyzed version shows also a high degree of regioretention and proceeds without isomerization. Allylic substrates with competitive allylic subunits react selectively at the sterically least hindered allylic position, in comparison to Ru‐catalyzed processes.
Coumarin‐Based Chromogenic Receptor for Ni2+ in Aqueous Medium Exhibiting a Reconfigurable Logic Gate Pattern
Authors: Mishra Rakesh K. , Upadhyay K. K. 
Published: July 2011

AbstractCoumarin‐based receptor R1 recognizes Ni2+ at sub‐micromolar levels in aqueous ethanolic medium (60:40) at physiological pH and exhibited INH logic function at pH values below 7. Additionally, this system showed reconfiguration to AND as well as TRANSFER logic functions in aqueous and dry dimethyl sulfoxide, respectively. The complexation of Ni2+ with R1 constituted the key step in its recognition, which was excellently demonstrated through single‐crystal XRD analysis.
Efficient Asymmetric Copper(I)‐Catalyzed Henry Reaction Using Chiral N‐Alkyl‐C1‐tetrahydro‐1,1′‐bisisoquinolines
Authors: Qiong ji Yao , Qi Gao , Judeh Zaher M. A. 
Published: July 2011

AbstractA series of closely related chiral N‐alkyl‐C1‐tetrahydro‐1,1′‐bisisoquinoline ligands only differing in the steric bulk of the alkyl groups has been examined in the asymmetric Henry reaction. A complex derived from the (R)‐N‐methyl‐1′,2′,3′,4′‐tetrahydro‐1,1′‐bisisoquinoline and copper(I) chloride proved to be a very efficient catalyst system that can promote the reaction of a wide range of aromatic and aliphatic aldehydes to give the expected nitroalcohol products in high yields (up to 99 %), excellent enantioselectivities (up to 94 % ee), and moderate diastereoselectivities (up to 1.6:1). This catalyst system is very general, requires no additives for activation, and is also simple in operation because no special precautions are taken to exclude moisture or air from the reaction flask.
Intramolecular Cycloaddition Reactions of 1‐Alkenyl‐3,4,5‐triaryl‐1,2‐diphosphacyclopenta‐2,4‐dienes
Authors: Zagidullin Almaz A. , Miluykov Vasili A. , Krivolapov Dmitry B. , Kharlamov Sergey V. , Latypov Shamil K. , Sinyashin Oleg G. , Hey‐Hawkins Evamarie 
Published: July 2011

Abstract1‐Alkenyl‐3,4,5‐triaryl‐1,2‐diphosphacyclopenta‐2,4‐dienes obtained by alkylation of sodium 3,4,5‐triaryl‐1,2‐diphosphacyclopentadienide with Br(CH2)nCH=CH2undergo, depending on thenvalue, either an intermolecular Diels–Alder reaction leading to polymeric compounds (n= 1, 4) or intramolecular cycloaddition reactions to give tricyclic cage phosphanes with high regio‐ and stereoselectivity (n= 2, 3). The structures and conformational behavior of these new tricyclic phosphanes are discussed.
Aquatic and terrestrial stressors in amphibians: A test of the double jeopardy hypothesis based on maternally and trophically derived contaminants
Authors: Todd Brian D , Bergeron Christine M , Hepner Mark J , Hopkins William A 
Published: July 2011

Abstract
Amphibians with biphasic life histories occupy aquatic and terrestrial habitats at different times in their lives, leading to a double jeopardy of contaminant risk in both habitats. The present study examines individual and interactive effects of mercury exposure to terrestrial adults and aquatic larvae on fitness-related traits of American toads, Bufo americanus. Eggs from reference mothers or contaminated mothers were allowed to hatch and larvae were fed diets of either no added Hg or 2.5 or 10 µg/g total Hg (dry wt). Both dietary and maternal Hg had adverse effects on developing larvae, but there was no interaction between these factors. Dietary Hg had a marginal effect of decreased survival with increasing Hg in the diet. Animals from Hg-exposed mothers weighed 14% less than those from reference mothers, and size at metamorphosis was directly correlated with hopping performance. Animals from Hg-exposed mothers also took longer to complete metamorphosis and had 2.5 times the prevalence of spinal malformations compared with those from reference mothers. Results of the present study demonstrate that amphibians do indeed face a double jeopardy of contaminant exposure stemming from terrestrial and aquatic environments, because both exposure pathways adversely affected developing offspring. The present study also demonstrates that all possible routes of exposure over an organism's life history must be examined to provide a comprehensive picture of the ecological consequences of habitat contamination. Environ. Toxicol. Chem. 2011;30:2277–2284. © 2011 SETAC
A yeast estrogen screen without extraction provides fast, reliable measures of estrogenic activity
Authors: Colosi Joseph C , Kney Arthur D 
Published: July 2011

Abstract
Yeast estrogen screen (YES) has been used since 1996 as a bioassay to quantify activity in wastewater. Here we present a modification of YES to measure estrogenic activity in water. This modification, called yeast estrogen screen no extraction (YESne), is faster and easier than the common method. The modified method can detect 17β-estradiol equivalent concentrations down to 1.1 ng/L. The median effective concentration value (EC50) is 1.2E-10. It detected average influent concentrations of 16.4 and 17.5 ng/L of 17β-estradiol equivalent at four Lehigh Valley, Pennsylvania, USA, wastewater treatment plants on September 18 and October 23, 2008, respectively, and average effluent concentrations of 5.1 and 8.1 ng/L of 17β-estradiol equivalent at the same plants on the two dates, respectively. Reduction in 17β-estradiol equivalent activity for the four wastewater treatment plants averaged 67.8 and 52.3%, respectively, for the September 18 and October 23 samples. The YESne is a simple, quick method for quantifying estrogenic activity that has been used successfully in nonmajor undergraduate classes and could be adapted by wastewater treatment plant laboratory technicians to measure influent and effluent estrogenicity on a regular basis. This practice will greatly increase our knowledge base of estrogenicity in wastewater before and after treatment. Environ. Toxicol. Chem. 2011;30:2261–2269. © 2011 SETAC
Cracking behavior of glazings with different thicknesses by radiant exposure
Authors: Li Liming , Xie Qiyuan , Cheng Xudong , Zhang Heping 
Published: July 2011

ABSTRACTFourteen experiments on cracking behavior of glazings with thicknesses of 3, 6, 8, and 10 mm by radiant exposure were carried out with a new experimental apparatus. The radiant power was controlled proportional to time square to simulate a time‐squared growth fire. An infrared thermal imaging camera was employed to monitor the temperature field of the unexposed glazing surface. Other important parameters including incident heat flux, local gas temperature, exposed surface temperature, and time of the first cracking were obtained. The relationship between the cracking behavior and glazing thickness was analyzed based on the experimental results. The results show that the protected edge temperature of glazing has a considerable rise when the first cracking occurred, which should be included in further modeling. It was also shown that thicker glazings have smaller surface temperature during the heating process and induce longer time to first crack. However, the critical temperature difference approximately remains constant for all glazings studied. Copyright © 2011 John Wiley & Sons, Ltd.
Short‐term safety and pharmacokinetic profile of asenapine in older patients with psychosis
Authors: Dubovsky Steven L. , Frobose Colleen , Phiri Phillip , de Greef Rik , Panagides John 
Published: July 2011

ObjectivesThe aim of this study was to assess the short‐term tolerability of two titration schedules of sublingual asenapine in older patients with psychosis, not associated with organic brain disease, and to compare asenapine pharmacokinetics in older patients versus younger adults with schizophrenia.MethodsPatients ≥65 years with psychosis without dementia were randomized for 6 weeks to two dose‐escalation regimens: 2 days at 2 mg twice daily (BID), 2 days at 5 mg BID, and 10 mg BID thereafter (slow escalation); or 4 days at 5 mg BID and 10 mg BID thereafter (rapid escalation). Clinical and pharmacokinetic assessments were performed in each group.ResultsOf 122 randomized patients, 76 (62.3%) completed the trial. The incidence of treatment‐emergent adverse events (AEs) was comparable (72.1%) with both regimens. The most frequently reported AEs were hypertension, headache, and somnolence; incidence of extrapyramidal symptom–related AEs was 5.7%. Mean end point weight change was 0.4 kg. For asenapine 5 and 10 mg BID, median times to maximum concentration were 1.00 and 1.06 h, respectively; maximum concentrations (Cmax) were 4.73 and 7.93 ng/mL; areas under the concentration versus time curve (0–12 h; AUC0−12) were 32.1 and 56.3 ng∙h/mL.ConclusionsDespite 12–30% increases in asenapine Cmax and AUC0−12 in older patients compared with previously published findings in younger schizophrenia patients, possibly as a result of slower drug clearance, asenapine was generally well tolerated during both dose‐escalation schedules. No dose adjustment appears to be necessary in older patients. Copyright © 2011 John Wiley & Sons, Ltd.
HOW PRICE RESPONSIVE IS THE DEMAND FOR SPECIALTY CARE?
Authors: Maciejewski Matthew L. , Liu Chuan‐Fen , Kavee Andrew L. , Olsen Maren K. 
Published: July 2011

SUMMARYObjectivesOutpatient visit co‐payments have increased in recent years. We estimate the patient response to a price change for specialty care, based on a co‐payment increase from $15 to $50 per visit for veterans with hypertension.Design, Setting, and PatientsA retrospective cohort of veterans required to pay co‐payments was compared with veterans exempt from co‐payments whose nonequivalence was reduced via propensity score matching. Specialty care expenditures in 2000–2003 were estimated via a two‐part mixed model to account for the correlation of the use and level outcomes over time, and results from this correlated two‐part model were compared with an uncorrelated two‐part model and a correlated random intercept two‐part mixed model.ResultsA $35 specialty visit co‐payment increase had no impact on the likelihood of seeking specialty care but induced lower specialty expenditures over time among users who were required to pay co‐payments. The log ratio of price responsiveness (semi‐elasticity) for specialty care increased from −0.25 to −0.31 after the co‐payment increase. Estimates were similar across the three models.ConclusionA significant increase in specialty visit co‐payments reduced specialty expenditures among patients obtaining medications at the Veterans Affairs medical centers. Longitudinal expenditure analysis may be improved using recent advances in two‐part model methods. Published 2011. This article is a US Government work and is in the public domain in the USA.
THE OH‐SO STRAIGHT AND NARROW PATH: CAN THE HEALTH CARE EXPENDITURE CURVE BE BENT?
Authors: Woodward Robert S. , Wang Le 
Published: July 2011

SUMMARYAlthough there is much talk about whether or not the current health care reform will ‘bend’ the health care expenditure ‘curve’, exactly which ‘curve’ is to be ‘bent’ is often ill‐specified. This essay notes that the ‘curve’ defined by the log of US national health care expenditures per capita plotted against the log of the US gross domestic product per capita has been remarkably straight since 1929 despite Medicare and Medicaid and all of the more recent reform attempts. After establishing stationarity and considering cointegration and endogeneity, the slope of this log–log relationship suggests a per capita expenditure–income elasticity of 1.388.The authors suggest two explanatory hypotheses consistent with the observed constant slope. First, many new technologies are endogenous because their introduction is determined by their expected market, which is in turn dependent on GDP per capita. Second, the authors emphasize the potential utility gained by spending disproportionately larger proportions of our growing income on hope, uncertainty‐reducing information, and consumer amenities, all of which may be independent of any improved health outcome. Copyright © 2011 John Wiley & Sons, Ltd.
Very short echo time improves the precision of glutamate detection at 3T in 1H magnetic resonance spectroscopy
Authors: Wijtenburg S. Andrea , Knight‐Scott Jack 
Published: July 2011

AbstractPurpose:To examine the precision of glutamate detection using a very short echo time (TE) phase rotation STEAM (PR‐STEAM) sequence.Materials and Methods:Spectrosopic data were acquired from the anterior cingulate gyrus in nine healthy adults using 6.5‐msec TE PR‐STEAM, 40‐msec TE PRESS, 72‐msec TE STEAM, and TE‐Averaging with an effective TE of 105 msec on a clinical 3T magnetic resonance imaging (MRI) system. All data were quantified using LCModel and reported as ratios relative to total creatine.Results:Glutamate Cramer‐Rao lower bounds were less than 8% for all sequences. The 6.5‐msec TE PR‐STEAM identified glutamate with the greatest precision (coefficient of variation [CV] of 7.1%), followed by TE‐Averaging (CV of 8.9%), 40‐msec TE PRESS (CV of 11.9%), and 72‐msec TE STEAM (CV of 13.8%).Conclusion:In the absence of spectral editing, glutamate is best detected in the human brain at 3T using very short TEs. J. Magn. Reson. Imaging 2011;. © 2011 Wiley‐Liss, Inc.
Comparison of Gd‐DTPA and Gd‐BOPTA for studying renal perfusion and filtration
Authors: Notohamiprodjo Mike , Pedersen Michael , Glaser Christian , Helck Andreas D. , Lodemann Klaus‐Peter , Jespersen Bente , Fischereder Michael , Reiser Maximilian F. , Sourbron Steven P. 
Published: July 2011

AbstractPurpose:To measure the systematic error in perfusion and filtration parameters derived from magnetic resonance (MR) renography caused by protein binding of MR contrast agents.Materials and Methods:Eight healthy Danish Landrace pigs were examined with dynamic contrast‐enhanced magnetic resonance imaging (DCE‐MRI). In four pigs a bolus of gadopentetate‐dimeglumine (Gd‐DTPA; no protein binding) was injected, followed by gadobenate‐dimeglumine (Gd‐BOPTA; 10% protein binding). The order was reversed in the other four pigs. A two‐compartment filtration model was generalized to allow for protein binding and fitted to whole‐cortex region of interest (ROI) curves. Single‐kidney plasma flow and volume, tubular flow (or GFR), and tubular transit time of both agents were compared.Results:The data show a strong systematic underestimation (P < 0.001) in GFR by Gd‐BOPTA (33 ± 7.2%), and no significant differences (P > 0.05) in plasma flow (2.2 ± 18%), plasma volume (−1.7 ± 7.8%) and tubular transit time (3.1 ± 7.2%). The order of injection had no significant effect.Conclusion:Theory and experiments agree that perfusion parameters of both agents are comparable, whereas GFR is underestimated with Gd‐BOPTA due to the dependence of relaxivity on protein content. Hence, GFR cannot be measured with protein‐bound contrast agents, but the proposed dual‐agent protocol may produce new functional indices measuring protein filtration. J. Magn. Reson. Imaging 2011;. © 2011 Wiley‐Liss, Inc.
Magnetic resonance tissue phase mapping: Analysis of age‐related and pathologically altered left ventricular radial and long‐axis dyssynchrony
Authors: Föll D. , Jung B. , Germann E. , Hennig J. , Bode Ch. , Markl M. 
Published: July 2011

AbstractPurpose:To employ magnetic resonance tissue phase mapping (TPM) for the assessment of age‐related left ventricular (LV) synchrony of radial and long‐axis motion in healthy volunteers and in hypertensive heart disease, dilated cardiomyopathy (DCM), and left bundle branch block (LBBB).Materials and Methods:TPM (spatial/temporal resolution = 1.3 × 2.6 mm2/13.8 msec) was employed to measure radial and long‐axis myocardial velocities in 58 healthy volunteers of three age groups and 37 patients (hypertensive, n = 18; DCM, n = 12; DCM and LBBB n = 7). Regional times‐to‐peak velocities (TTP) in systole and diastole were derived for all LV segments. Four measures of dyssynchrony were defined as the standard deviation of systolic and diastolic TTP for radial and long‐axis motion.Results:Systolic radial and diastolic long‐axis dyssynchrony was increased (P < 0.01) in all patient groups compared to controls. Multiple regressions revealed a significant relationship of dyssynchrony with LV ejection fraction and mass for systolic radial (P < 0.001 resp. P = 0.02), diastolic radial (P < 0.001 resp. P < 0.05), and long‐axis (P < 0.001 resp. P = 0.001) motion. Diastolic dyssynchrony correlated with the LV remodeling index (P < 0.05) and increased with age (P < 0.03). Systolic long‐axis dyssynchrony was not influenced by disease or LV function.Conclusion:Radial systolic and long‐axis diastolic dyssynchrony were the most sensitive markers for altered dyssynchrony in hypertensive heart disease or DCM. Future studies are needed to evaluate the diagnostic value of TPM‐derived dyssynchrony parameters. J. Magn. Reson. Imaging 2011;. © 2011 Wiley‐Liss, Inc.
Four‐dimensional transcatheter intraarterial perfusion MRI monitoring of radiofrequency ablation of rabbit VX2 liver tumors
Authors: Sato Kent T. , Wang Dingxin , Lewandowski Robert J. , Ryu Robert K. , Klein Rachel A. , Salem Riad , Larson Andrew C. , Omary Reed A. 
Published: July 2011

AbstractPurpose:To investigate the hypothesis that four‐dimensional (4D) transcatheter intraarterial perfusion (TRIP) magnetic resonance imaging (MRI) can quantify immediate perfusion changes after radiofrequency (RF) ablation in rabbit VX2 liver tumors.Materials and Methods:Nine New Zealand White rabbits were used to surgically implant VX2 liver tumors. During ultrasound‐guided RF ablation, tumors received either a true or sham ablation. After selective catheterization of the left hepatic artery under x‐ray fluoroscopy, we acquired pre‐ and post‐RF ablation 4D TRIP MR images using 3 mL of 2.5% intraarterial gadopentetate dimeglumine. Two regions‐of‐interest were drawn upon each tumor to generate signal‐intensity time curves. Area under the curve (AUC) was calculated to provide semiquantitative perfusion measurements that were compared using a paired t‐test (α = 0.05). Ablated tissue was visually confirmed on pathology using Evans blue dye.Results:Mean AUC perfusion of VX2 tumors for the true ablation group decreased by 92.0% (95% confidence interval [CI]: 83.3%–100%), from 1913 (95% CI: 1557, 2269) before RF ablation to 76.6 (95% CI: 18.4, 134.8) after RF ablation (a.u., P < 0.001). Sham‐ablated tumors demonstrated no significant perfusion changes.Conclusion:4D TRIP MRI can quantify liver tumor perfusion reductions in VX2 rabbits after RF ablation. This MRI technique can potentially be used to improve tumor response assessment at the time of RF ablation. J. Magn. Reson. Imaging 2011;. © 2011 Wiley‐Liss, Inc.