bluuebunny/crossref_metadata_2025 huggingface dataset:
Yolk sac endoderm is the major source of serum proteins and lipids and is involved in the regulation of vascular integrity in early chick development
Authors: Nakazawa Fumie , Alev Cantas , Jakt Lars M. , Sheng Guojun
Published: July 2011

An important function of the vascular system is nutrient delivery. In adult animals, this is mediated through a close contact of the mesoderm‐derived vasculature with the endoderm‐derived enterocytes and hepatocytes. During embryonic development, the yolk sac (YS) endoderm has been suggested to play a similar role. Physiological and molecular nature of the contact between the YS endoderm and the vasculature is not well‐understood. To understand roles of the YS endoderm in early development, we used the avian model and carried out a gene expression profiling analysis of isolated area vasculosa YS endoderm tissues from embryonic day 2–4 chick embryos, covering the first 48 hr of postcirculation development. Genes involved in lipid metabolism are highly enriched, indicating an active modification of lipid components during their transfer from the yolk to the circulatory system. We also uncovered genes encoding major serum proteins and key regulators of vascular integrity. In particular, PTGDS, an enzyme controlling the last step of prostaglandin D2 production, shows high expression in the YS endoderm. Experimental introduction of prostaglandin D2 into embryonic circulation led to intraembryonic vessel rupture. These data suggest that the YS endoderm is the major, if not exclusive, source of lipid and protein constituents of the early embryonic serum and plays an important role in the regulation of vascular integrity in developing embryo. Developmental Dynamics 240:2002–2010, 2011. © 2011 Wiley‐Liss, Inc.
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

Bone 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

The 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

PCP 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

By 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

Wilkinson'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

Coumarin‐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

A 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

1‐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

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

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

Fourteen 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

Objectives

The 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.

Methods

Patients ≥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.

Results

Of 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.

Conclusions

Despite 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

Objectives

Outpatient 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 Patients

A 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.

Results

A $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.

Conclusion

A 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

Although 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

Purpose:

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

Purpose:

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

Purpose:

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

Purpose:

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.
Nitrite Oxidation in Ion Chromatography‐Electrospray Ionization‐Tandem Mass Spectrometry (IC‐ESI‐MS/MS)
Authors: Farhat Ali , Dooley Alek N. , Ahmad Farrukh
Published: July 2011

Nitrite anions are formed in the human body and in the natural environment as intermediate chemical compounds during the reduction of nitrate, a ubiquitous anthropogenic contaminant introduced into the environment primarily through fertilizer use. Multiple reaction monitoring (MRM) in ion chromatography‐electrospray ionization‐tandem mass spectrometry (IC‐ESI‐MS/MS) is a promising new technique for quantifying and confirming the identity of anions in complex aqueous mixtures. In this article, we present the results of a short investigation devised to: (1) compare the signal generated by the MRM transitions for nitrite with those for nitrate, (2) isolate the source of the signal from these MRM transitions occurring within the IC‐ESI‐MS/MS instrument and (3) assess the relationship between the observed MRM signals for nitrite. The MRM transitions used in this study were m/z 62 (NO3−) →m/z 46 (NO2−) and m/z 46 (NO2−) →m/z 46 (NO2−). Results of the investigation revealed the association of both MRM transitions with the nitrite chromatographic peak, indicating the occurrence of nitrite oxidation to nitrate at the ESI interface before the first quadrupole. Calibrations for both MRM signals, as well as their sum, were found to be linear. However, the ratio of m/z 62 →m/z 46 to m/z 46 →m/z 46 (indicating an extent of oxidation) ranged from 35 to 56% over a nitrite concentration range of 10 to 100 ppm, showing no clear trend associated with concentration. Copyright © 2011 John Wiley & Sons, Ltd.
Ectopic chondro‐ossification and erroneous extracellular matrix deposition in a tendon window injury model
Authors: Lui Pauline Po Yee , Cheuk Yau Chuk , Lee Yuk Wa , Chan Kai Ming
Published: July 2011

The acquisition of chondro‐osteogenic phenotypes and erroneous matrix deposition may account for poor tissue quality after acute tendon injury. We investigated the presence of chondrocyte phenotype, ossification, and the changes in the expression of major collagens and proteoglycans in the window wound in a rat patellar tendon window injury model using histology, von Kossa staining and immunohistochemistry of Sox 9, major collagens, and proteoglycans. Our results showed that the repair tissue did not restore to normal after acute injury. Ectopic chondrogenesis was observed in 33% of samples inside wound at week 4 while ectopic ossification surrounded by chondrocyte‐like cells were observed in the window wound in 50% of samples at week 12. There was sustained expression of biglycan and reduced expression of aggrecan and decorin in the tendon matrix in the repair tissue. The erroneous deposition of extracellular matrix and ectopic chondro‐ossification in the repair tissue, both might influence each other, might account for the poor tissue quality after acute injury. Higher expression of biglycan and aggrecan were observed in the ectopic chondro‐ossification sites in the repair tissue, suggesting that they might have roles in ectopic chondro‐osteogenesis. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 30:37–46, 2012
Forensic examination of multilayer white paint by lateral scanning Raman spectroscopy
Authors: Stewart S.P. , Bell S.E.J. , Armstrong W.J. , Kee G. , Speers S.J.
Published: July 2011

Multilayer samples of white architectural paint potentially have very high evidential value in forensic casework, because the probability that two unrelated samples will have the same sequence of layers is extremely low. However, discrimination between the different layers using optical microscopy is often difficult or impossible. Here, lateral scanning Raman spectroscopy has been used to chemically map the cross‐sections of multilayer white paint chips. It was found that the spectra did allow the different layers to be delineated on the basis of their spectral features. The boundaries between different layers were not as sharp as expected, with transitions occurring over length scales of > 20 µm, even with laser spot diameters < 4 µm. However, the blurring of the boundaries was not so large as to prevent recording and identification of spectra from each of the layers in the samples. This method clearly provides excellent discrimination between different multilayer white paint samples and can readily be incorporated into existing procedures for examination of paint transfer evidence. © 2011 Crown copyright.
Precise determination of Mg/Fe ratios applicable to terrestrial olivine samples using Raman spectroscopy
Authors: Ishibashi Hidemi , Arakawa Masashi , Yamamoto Junji , Kagi Hiroyuki
Published: July 2011

The relationship between Mg# [ = 100 Mg/(Mg + Fe) in mol] and the Raman shift was analyzed precisely for olivine [(Mg, Fe)2SiO4] samples with Mg# between 100 and 62.8. Two prominent peaks at 826–820 cm−1 (peak 1) and 858–849 cm−1 (peak 2) and three subordinate peaks at 883–881 cm−1 (peak 3), 920–914 cm−1 (peak 4), and 967–951 cm−1 (peak 5) were observed to shift monotonously to lower wavenumbers with decreasing Mg#. The ΔMg#( = Mg#ref − Mg#) versus Δν(= νref − ν) can be linearly regressed for each peak as ΔMg# = A Δν, where ν is a peak wavenumber of olivine with Mg# ranging from 100 to 62.8, and νref is that of olivine with a reference value of Mg#, namely, Mg#ref. We set Mg#ref as 100 (i.e.pure forsterite Mg2SiO4) whereas A is a regression parameter (5.789, 4.294, 12.34, 6.348, and 2.09, respectively,for peaks 1, 2, 3, 4, and 5). This equation enables us to avoid small inter‐laboratory differences of wavenumber calibration. The equation for peak 2 yields estimations of Mg# in geologically satisfactory precision, ± 1 Mg# (1σ) in the Mg# range of 100–62.8. Copyright © 2011 John Wiley & Sons, Ltd.
Polyenic pigments from the Brazilian octocoral Phyllogorgia dilatata Esper, 1806 characterized by Raman spectroscopy
Authors: Maia Lenize F. , de Oliveira Vanessa E. , de Oliveira Maria Edwiges R. , Fleury Beatriz G. , de Oliveira Luiz Fernando C.
Published: July 2011

Phyllogorgia dilatata is a Brazilian endemic gorgonian with a natural color ranging from white to pale yellow. An unusual violet pigmentation has been observed in colonies with tissue damage and skeleton anomalies. In order to investigate the chemical composition of these pigments, we have used in situ Raman spectroscopy to characterize the white/cream and violet tissues as well as sclerites, a skeletal component consisting of calcite, from both samples. Violet/purple pigmentation surrounding tissue necrosis is characterized as purpling, in response to fungus infection and allelopathic interactions. The spectroscopic analysis of the white‐cream tissues, designated as healthy, has revealed the presence of the carotenoid peridinin, typical of the endosymbiont that harbors this species; however, peridinin was not observed in the colorless sclerites analysis, presenting bands exclusively of calcite. In contrast, the violet coloration of damaged tissue has also been observed in the sclerites. Both showed Raman bands corresponding to unmethylated polyunsaturated aldehyde, besides calcite bands. This is the first report of purpling in a Brazilian octocoral, identified as a derivative of the biochromes named psittacofulvins, which have been reported as exclusive in parrots. Copyright © 2011 John Wiley & Sons, Ltd.
Raman scattering by folded acoustic phonons in InGaN/GaN superlattices
Authors: Ibáñez J. , Rapaport A. , Boney C. , Oliva R. , Cuscó R. , Bensaoula A. , Artús L.
Published: July 2011

We use Raman scattering to investigate the folded longitudinal acoustic (LA) phonons in a series of InxGa1−xN/GaN superlattices (SLs) grown by molecular beam epitaxy with different compositions (15% < x < 38%) and SL periods (from 8 to 20 nm). A novel, ultralow wavenumber filtering module, which provides access to ultralow wavenumber Raman modes on single‐grating spectrometers, has been used to perform the Raman measurements. Zone‐folding effects are observed, and the wavenumber behavior of the folded LA modes is well reproduced with a linear dispersion for the folded LA modes as predicted by elastic continuum theory. We employ the wavenumber of the doublets to evaluate the period of the SLs. Copyright © 2011 John Wiley & Sons, Ltd.
The effect of ischemic preconditioning on redox status during liver resections—randomized controlled trial
Authors: Hahn Oszkár , Blázovics Anna , Váli László , Kupcsulik Peter K.
Published: July 2011

Background and Objectives

Portal clamping during liver resection decreases intraoperative blood loss, but causes ischemic‐reperfusion (I‐R) injury. Intermittent portal clamping (IPC) and ischemic preconditioning (IP) decreased I‐R injury in animal models. Most of the human studies about IP excluded cirrhotic patients, whose liver is more vulnerable to I‐R injury. The effect of IP and IPC during extended liver resection was investigated in this randomized controlled trial, with special respect to cirrhotic patients.

Methods

One hundred sixty patients (100 normal liver, 60 cirrhotic) undergoing major liver resection were randomized to receive IPC (15 min ischemia, 5 min reperfusion), or IP (10 min ischemia, 10 min reperfusion). Serum oxygen‐derived free radicals (ODFR) and antioxidant concentrations (preoperative, after reperfusion and 7th postoperative day), such as “conventional” liver tests (preoperative, 1st, 3rd, and 7th postoperative day) were measured.

Results

IP resulted in significantly lower peak ODFR, AST, ALT, and bilirubin levels after liver resection than IPC (P < 0.05). The level of serum antioxidants after reperfusion was significantly higher in IP than in IPC groups (P < 0.05). In cirrhotic patients without IP none of these values normalized until the 7th postoperative day.

Conclusions

Ischemic preconditioning—especially in patients with liver cirrhosis—is a suitable method to decrease the I‐R injury of the liver. J. Surg. Oncol. 2011; 104:647–653. © 2011 Wiley Periodicals, Inc.
Iron‐deficiency anemia: A predictor of diminished disease‐free survival of T3N0M0 stage colon cancer
Authors: Zhen Li , Zhe Sun , Zhenning Wang , Zhifeng Miao , Zhidong Lv , Xiaoxia Li , Jianguang Yang , Huimian Xu
Published: July 2011

Purpose

The aim of this study was to determine whether iron‐deficiency anemia (IDA) predicts long‐term oncologic outcomes in patients with TNM stage II colon cancer.

Methods

Clinical and follow‐up data were extracted from a prospective colon cancer database. Univariate and multivariate analyses were performed to identify IDA and other predictors of long‐term oncologic outcomes.

Results

Among 644 patients, 147 (22.8%) patients presented with IDA. The data were stratified by T3N0M0 and T4N0M0. The distribution difference of IDA between the two subsets was not significant (P = 0.340). But in the T4N0M0 subset, the incidence of IDA increased with the depth of tumor penetration (75.9% and 18.2% for the patients with and without adjacent organ involvement, respectively, P = 0.011). IDA predicted a worse disease‐free survival among patients with T3N0M0 cancer (472 patients; log‐rank test, P = 0.016; Cox regression, P = 0.009), but it was not a predictor in T4N0M0 cancer patients (172 patients; log‐rank test, P = 0.016; Cox regression, P > 0.05).

Conclusions

IDA was an independent predictor of long‐term outcome in T3N0M0 stage, but not in T4N0M0 colon cancer. T3N0M0 stage colon cancer patients with IDA could be included in future trials of adjuvant therapies. J. Surg. Oncol. 2012;105:371–375. © 2011 Wiley Periodicals, Inc.
Genetic polymorphism of the plasminogen activator inhibitor‐1 is associated with an increased risk of endometrial cancer
Authors: Su Chung‐Kuang , Yeh Kun‐Tu , Yeh Chao‐Bin , Wang Po‐Hui , Ho Esther Shih‐Chu , Chou Ming‐Chih , Liu Kai‐Cheng , Yang Shun‐Fa , Yi Yu‐Chiao
Published: July 2011

Background and Objectives

To investigate the association of uPA system genes, including uPA, uPA receptor (uPAR), and plasminogen activator inhibitor (PAI)‐1 gene polymorphisms, with risk of endometrial cancer.

Methods

In the present case control study, we enrolled a total of 134 patients with endometrial cancer confirmed by histopathology and 302 unrelated healthy individuals. Genetic polymorphisms of uPA system genes, including uPA rs4065 C/T SNP, uPAR rs344781 T/C SNP, and PAI‐1 rs1799889 4G/5G SNP were genotyped by polymerase chain reaction‐restriction fragment length polymorphism (PCR‐RFLP) genotyping analysis.

Results

Frequency of PAI‐1 rs1799889 4G/4G genotype and 4G allele differed significantly between patients with endometrial cancer (36.6% and 61.6%, respectively) and healthy individuals (25.5% and 52.2%, respectively). Individuals with PAI‐1 rs1799889 4G/4G genotype were at higher risk of endometrial cancer (OR = 2.26; 95% CI: 1.20–4.27). Stratification analysis showed individuals with PAI‐1 rs1799889 4G/4G genotype were at elevated risk for endometrioid type (OR = 2.49; 95% CI 1.27–4.88), low stage (stages I–II) endometrial cancer (OR = 2.34; 95% CI 1.21–4.52). However, no significant differences in uPA C/T SNP, uPAR T/C SNP genotypes were observed between endometrial carcinoma cases and controls.

Conclusions

Individuals with PAI‐1 rs1799889 4G/4G genotype were at significantly higher risk of endometrial cancer in this study. J. Surg. Oncol. 2011; 104:755–759. © 2011 Wiley Periodicals, Inc.
Ex vivo evaluation of femtosecond pulse laser incision of urinary tract tissue in a liquid environment: Implications for endoscopic treatment of benign ureteral strictures
Authors: Liang Jun‐Hao , Kang Jian , Pan Yu‐Long , Zhang Liang , Qi Jun
Published: July 2011

Background

The femtosecond (FS) pulse laser incises soft tissues with minimal peripheral damage and is a promising cutting tool for ureteroscopic endoureterotomy of benign ureteral strictures.

Objective

To evaluate the feasibility of applying the FS laser to ureteroscopic endoureterotomy.

Materials and Methods

A commercial Ti:Sapphire regenerative amplifier system (Coherent, RegA 9050, USA) was used in this study. Normal saline, 5% glucose solution, 4% mannitol solution, distilled water, and a 1% (v/v) suspension of whole blood with each of these solutions were tested for their attenuation rate (AR) of the FS laser's power. Bladder specimens from Sprague–Dawley (SD) rats were used as a surrogate model. The laser incised slots of 2 mm in length at bladder samples using three power grades (5×, 10×, and 20× the threshold power) combined with five effective pulse rates (40, 20, 10, 5, and 2.5 kHz), both in air and in normal saline. After samples were processed with standard hematoxylin–eosin staining procedures, the incision depth and collateral damage range were determined microscopically.

Results

The ARs of blood suspensions with each of the three isosmotic solutions were significantly higher than the other five solutions (P < 0.001). The FS laser's cutting depth and the collateral damage were increased with the laser power or power density but the collateral damages were less than 100 µm. Microbubble formation was detected in the liquid environments tested and influenced the effective laser power.

Conclusions

Endoscopic application of the FS laser is feasible. Microbubble formation with the laser incision, however, may influence cutting effects. Proposed methods to address these issues include increasing the irrigation rate, using distilled water as irrigation or using gas insufflation instead of irrigation. It is necessary to evaluate these methods, as well as the long‐term biologic response to laser incision, on living animal models in endoscopic settings before use on humans. Lasers Surg. Med. 43:516–521, 2011. © 2011 Wiley‐Liss, Inc.
A light‐activated method for repair of corneal surface defects
Authors: Wang Ying , Kochevar Irene E. , Redmond Robert W. , Yao Min
Published: July 2011

Background and Objective

Amniotic membrane transplantation (AMT) sealed with sutures has been routinely used to treat ocular surface defects (OSD). However, the sutures used to secure the graft on the cornea cause additional injury, infection, and scarring. A new light‐activated technique, called photochemical tissue bonding (PTB), has been developed for securing amniotic membrane (AM) over the corneal surface. The purpose of this study was to compare PTB versus traditional sutures in AMT for repair of OSD.

Materials and Methods

An OSD was created in the left eye of 40 rabbits. The eyes were randomized into two repair groups: AMT using sutures and AMT using PTB with 0.1% Rose Bengal (RB) and 532 nm laser at 0.4 W/cm2 for 200 seconds. Eyes were examined for re‐epithelialization, inflammation, neovascularization, and scarring histologically and biochemically on postoperative days 1, 3, 14, and 28.

Results

PTB strongly bonded AM over corneal defects. Corneal re‐epithelialization did not differ significantly between the suture and PTB groups. Histology, immunohistology and Western blotting revealed that the numbers of inflammatory cells and the level of tumor necrosis factor‐alpha in the PTB group were dramatically lower than those in the suture group on postoperative day 3. Many fewer neo‐vessels were present in the PTB group (2.91 ± 1.00) compared to the suture group (4.33 ± 1.15) at day 28 (P < 0.05). The collagen fibers in the PTB group were well organized and orientated as assessed by second harmonic generation microscopy, suggesting that PTB treatment led to less corneal scarring.

Conclusions

PTB is a superior method for securing AM over OSD with improved wound healing compared to sutures. Lasers Surg. Med. 43:481–489, 2011. © 2011 Wiley‐Liss, Inc.
Nanosecond pulse lasers for retinal applications
Authors: Wood John P.M. , Plunkett Malcolm , Previn Victor , Chidlow Glyn , Casson Robert J.
Published: July 2011

Background and Objectives

Thermal lasers are routinely used to treat certain retinal disorders although they cause collateral damage to photoreceptors. The current study evaluated a confined, non‐conductive thermal, 3‐nanosecond pulse laser in order to determine how to produce the greatest therapeutic range without causing collateral damage. Data were compared with that obtained from a standard thermal laser.

Materials and Methods

Porcine ocular explants were used; apposed neuroretina was also in place for actual laser treatment. After treatment, the retina was removed and a calcein‐AM assay was used to assess retinal pigmented epithelium (RPE) cell viability in the explants. Histological methods were also employed to examine lased transverse explant sections. Three nanoseconds pulse lasers with either speckle‐ or gaussian‐beam profile were employed in the study. Comparisons were made with a 100 milliseconds continuous wave (CW) 532 nm laser. The therapeutic energy range ratio was defined as the minimum visible effect threshold (VET) versus the minimum detectable RPE kill threshold.

Results

The 3‐nanosecond lasers produced markedly lower minimum RPE kill threshold levels than the CW laser (e.g., 36 mJ/cm2 for speckle‐beam and 89 mJ/cm2 for gaussian‐beam profile nanosecond lasers vs. 7,958 mJ/cm2 for CW laser). VET values were also correspondingly lower for the nanosecond lasers (130 mJ/cm2 for 3 nanoseconds speckle‐beam and 219 mJ/cm2 for gaussian‐beam profile vs. 1,0346 mJ/cm2 for CW laser). Thus, the therapeutic range ratios obtained with the nanosecond lasers were much more favorable than that obtained by the CW laser: 3.6:1 for the speckle‐beam and 2.5:1 for the gaussian‐beam profile 3‐nanosecond lasers versus 1.3:1 for the CW laser.

Conclusions

Nanosecond lasers, particularly with a speckle‐beam profile, provide a much wider therapeutic range of energies over which RPE treatment can be performed, without damage to the apposed retina, as compared with conventional CW lasers. These results may have important implications for the treatment of retinal disease. Lasers Surg. Med. 43:499–510, 2011. © 2011 Wiley‐Liss, Inc.
Survivin promotes glioma angiogenesis through vascular endothelial growth factor and basic fibroblast growth factor in vitro and in vivo
Authors: Wang Peng , Zhen Haining , Zhang Jiashu , Zhang Wei , Zhang Rui , Cheng Xin , Guo Geng , Mao Xinggang , Wang Jingbo , Zhang Xiang
Published: July 2011

Survivin is involved in multiple signaling mechanisms in tumor maintenance, and accumulated studies elucidate that knockdown of survivin in endothelial cells could inhibit angiogenesis; however, the role of survivin in tumor cells to regulate tumor‐derived angiogenesis remains largely unclear. In the present study 80 cases of brain glioma were chosen and protein expressions of survivin, vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), and platelet‐derived growth factor (PDGF) in glioma cells were investigated by immunohistochemistry (IHC). Human umbilical vein endothelial cells (HUVEC) were cocultured with human glioma U251 wild‐type cells, U251 cells survivin silenced, SHG44 wild‐type cells, and SHG44 survivin‐overexpressing cells, respectively. The proliferation and migration of HUVEC were evaluated by MTT assay and transwell chamber assay. The microvessels density (MVD) marked by CD31 expression in vascular endothelial cells in glioma xenografts in nude mice was detected by IHC. VEGF, bFGF, and PDGF in the aforementioned cells were detected by quantitive PCR (qPCR), Western blot, ELISA, and IHC in vitro and in vivo. The results showed that VEGF immunoreactivity score (IRS), bFGF IRS, and PDGF IRS were all positively correlated with survivin IRS in gliomas, respectively (P < 0.01). Survivin in human glioma cells could significantly promote the proliferation and migration of HUVEC and increase MVD, which could be contributed to survivin‐dependent burst of VEGF and bFGF expression, followed by increase of tumor growth and proliferation. In summary, survivin, through upregulation of VEGF and bFGF, plays an essential role during glioma angiogenesis. © 2011 Wiley Periodicals, Inc.
Spin dephasing under nonlinear gradients: Implications for imaging and field mapping
Authors: Galiana Gigi , Stockmann Jason P. , Tam Leo , Constable R. Todd
Published: July 2011

This work examines the prototypical MR echo that would be expected for a voxel of spins evolving in a strong nonlinear field, specifically focusing on the quadratic z2 − ½(x2 + y2) field. Dephasing under nonlinear gradients is increasingly relevant given the growing interest in nonlinear imaging, and here, we report several notable differences from the linear case. Most notably, in addition to signal loss, intravoxel dephasing under gradients creating a wide and asymmetric frequency distribution across the voxel can cause skewed and nonlinear phase evolution. After presenting the qualitative and analytical origins of this difference, we experimentally demonstrate that neglecting these dynamics can lead to significant errors in sequences that assume phase evolution is proportional to voxel frequency, such as those used for field mapping. Finally, simplifying approximations to the signal equations are presented, which not only provide more intuitive forms of the exact expression but also result in simple rules to predict key features of the nonlinear evolution. Magn Reson Med, 2011. © 2011 Wiley‐Liss, Inc.