bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of performance metrics for bias field correction in MR brain images
Authors: Chua Zin Yan , Zheng Weili , Chee Michael W.L. , Zagorodnov Vitali
Published: May 2009

Purpose

To investigate inconsistencies between common performance measures for bias field correction reported in several recent studies and propose a solution.

Materials and Methods

A set of synthetic images of a normal brain from the Montréal Simulated Brain Database (SBD) was processed using two bias field correction algorithms. The parameters of these algorithms were varied and the resulting outputs were assessed using several performance measures. Validity was estimated using Spearman rank correlation coefficient between “indirect” performance measures and the L2 norm of the difference between true and estimated bias fields. The “indirect” performance measures tested were: coefficients of variation of white matter (WM) and gray matter (GM), coefficient of joint variation. These measures were tested on bias field‐corrected images that were permuted in terms of quality of WM/GM segmentation as well as the presence or absence of light smoothing.

Results

Existing indirect performance measures yielded poor validity scores, explaining the inconsistencies reported in the literature. Image noise and inappropriate inclusion of partial volume voxels and neighboring tissues were found to be contributory. Combining conservative segmentation and smoothing significantly improved validity.

Conclusion

The use of indirect performance measures in the conventional manner to guide bias field correction is unreliable. Using these metrics on lightly smoothed images with conservatively segmented tissues proved more reliable for guiding the selecting of parameters for nonuniformity correction ultimately contributing to more accurate brain segmentation. J. Magn. Reson. Imaging 2009;29:1271–1279. © 2009 Wiley‐Liss, Inc.
Predicting survival and early clinical response to primary chemotherapy for patients with locally advanced breast cancer using DCE‐MRI
Authors: Johansen Roar , Jensen Line R. , Rydland Jana , Goa Pål E. , Kvistad Kjell A. , Bathen Tone F. , Axelson David E. , Lundgren Steinar , Gribbestad Ingrid S.
Published: May 2009

Purpose

To evaluate dynamic contrast‐enhanced magnetic resonance imaging (DCE‐MRI) as a tool for early prediction of response to neoadjuvant chemotherapy (NAC) and 5‐year survival in patients with locally advanced breast cancer.

Materials and Methods

DCE‐MRI was performed in patients scheduled for NAC (n = 24) before and after the first treatment cycle. Clinical response was evaluated after completed NAC. Relative signal intensity (RSI) and area under the curve (AUC) were calculated from the DCE‐curves and compared to clinical treatment response. Kohonen and probabilistic neural network (KNN and PNN) analysis were used to predict 5‐year survival.

Results

RSI and AUC were reduced after only one cycle of NAC in patients with clinical treatment response (P = 0.02 and P = 0.08). The mean and 10th percentile RSI values before NAC were significantly lower in patients surviving more than 5 years compared to nonsurvivors (P = 0.05 and 0.02). This relationship was confirmed using KNN, which demonstrated that patients who remained alive clustered in separate regions from those that died. Calibration of contrast enhancement curves by PNN for patient survival at 5 years yielded sensitivity and specificity for training and testing ranging from 80%–92%.

Conclusion

DCE‐MRI in locally advanced breast cancer has the potential to predict 5‐year survival in a small patient cohort. In addition, changes in tumor vascularization after one cycle of NAC can be assessed. J. Magn. Reson. Imaging 2009;29:1300–1307. © 2009 Wiley‐Liss, Inc.
Improved time‐of‐flight magnetic resonance angiography with IDEAL water‐fat separation
Authors: Grayev Allison , Shimakawa Ann , Cousins Joseph , Turski Patrick , Brittain Jean , Reeder Scott
Published: May 2009

Purpose

To implement IDEAL (iterative decomposition of water and fat using echo asymmetry and least squares estimation) water‐fat separation with 3D time‐of‐flight (TOF) magnetic resonance angiography (MRA) of intracranial vessels for improved background suppression by providing uniform and robust separation of fat signal that appears bright on conventional TOF‐MRA.

Materials and Methods

IDEAL TOF‐MRA and conventional TOF‐MRA were performed in volunteers and patients undergoing routine brain MRI/MRA on a 3T magnet. Images were reviewed by two radiologists and graded based on vessel visibility and image quality.

Results

IDEAL TOF‐MRA demonstrated statistically significant improvement in vessel visibility when compared to conventional TOF‐MRA in both volunteer and clinical patients using an image quality grading system. Overall image quality was 3.87 (out of 4) for IDEAL versus 3.55 for conventional TOF imaging (P = 0.02). Visualization of the ophthalmic artery was 3.53 for IDEAL versus 1.97 for conventional TOF imaging (P < 0.00005) and visualization of the superficial temporal artery was 3.92 for IDEAL imaging versus 1.97 for conventional TOF imaging (P < 0.00005).

Conclusion

By providing uniform suppression of fat, IDEAL TOF‐MRA provides improved background suppression with improved image quality when compared to conventional TOF‐MRA methods. J. Magn. Reson. Imaging 2009;29:1367–1374. © 2009 Wiley‐Liss, Inc.
Spectral resolution amelioration by deconvolution (SPREAD) in MR spectroscopic imaging
Authors: Dong Zhengchao , Peterson Bradley S.
Published: May 2009

Purpose

To develop, implement, and evaluate a novel postprocessing method for enhancing the spectral resolution of in vivo MR spectroscopic imaging (MRSI) data.

Materials and Methods

Magnetic field inhomogeneity across the imaging volume was determined by acquiring MRI datasets with two differing echo times. The lineshapes of the MRSI spectra were derived from these field maps by simulating an MRSI scan of a virtual sample whose resonance frequencies varied according to the observed variations in the magnetic field. By deconvolving the lineshapes from the measured MRSI spectra, the linebroadening effects of the field inhomogeneities were reduced significantly.

Results

Both phantom and in vivo proton MRSI spectra exhibited significantly enhanced spectral resolutions and improved spectral lineshapes following application of our method. Quantitative studies on a phantom show that, on average, the full width at half maximum of water peaks was reduced 42%, the full width at tenth maximum was reduced 38%, and the asymmetries of the peaks were reduced 86%.

Conclusion

Our method reduces the linebroadening and lineshape distortions caused by magnetic field inhomogeneities. It substantially improves the spectral resolution and lineshape of MRSI data. J. Magn. Reson. Imaging 2009;29:1395–1405. © 2009 Wiley‐Liss, Inc.
Whole heart magnetization‐prepared steady‐state free precession coronary vein MRI
Authors: Stoeck Christian T. , Han Yuchi , Peters Dana C. , Hu Peng , Yeon Susan B. , Kissinger Kraig V. , Goddu Beth , Goepfert Lois , Manning Warren J. , Kozerke Sebastian , Nezafat Reza
Published: May 2009

Purpose

To compare two coronary vein imaging techniques using whole‐heart balanced steady‐state free precession (SSFP) and a targeted double‐oblique spoiled gradient‐echo (GRE) sequences in combination with magnetization transfer (MT) preparation sequence for tissue contrast improvement.

Materials and Methods

Nine healthy subjects were imaged with the proposed technique. The results are compared with optimized targeted MT prepared GRE acquisitions. Both quantitative and qualitative analyses were performed to evaluate each imaging method.

Results

Whole‐heart images were successfully acquired with no visible image artifact in the vicinity of the coronary veins. The anatomical features and visual grading of both techniques were comparable. However, the targeted small slab acquisition of the left ventricular lateral wall was superior to whole‐heart acquisition for visualization of relevant information for cardiac resynchronization therapy (CRT) lead implantation.

Conclusion

We demonstrated the feasibility of whole‐heart coronary vein MRI using a 3D MT‐SSFP imaging sequence. A targeted acquisition along the lateral left ventricular wall is preferred for visualization of branches commonly used in CRT lead implantation. J. Magn. Reson. Imaging 2009;29:1293–1299. © 2009 Wiley‐Liss, Inc.
Aging effects on human calf muscle properties assessed by MRI at 3 Tesla
Authors: Schwenzer Nina F. , Martirosian Petros , Machann Jürgen , Schraml Christina , Steidle Günter , Claussen Claus D. , Schick Fritz
Published: May 2009

Purpose

To determine age‐related changes in MR properties as T2 and T2* relaxation times, fat content, and magnetization transfer in the human calf, and comparison of these effects in different muscle groups.

Materials and Methods

Studies were performed on 12 “younger” (mean, 31.2 ± 6.1 years) and 11 “older” healthy adult individuals (mean, 66.1 ± 7.8 years). The tibialis anterior muscle, the soleus muscle and the gastrocnemius muscle were examined at rest in a 3 Tesla whole‐body MR unit. T2 and T2*, muscular fat content and magnetization transfer ratios (MTR) were determined. Results of the two age groups were compared, and differences between the muscle groups were investigated.

Results

Increase of T2 and muscular fat was detected with age with significant difference between the age groups. The extent of fatty infiltration was much more variable for the “older” group. For both age groups, the tibialis anterior muscle showed the lowest fat content with 1.2 ± 0.4% in the “young” group and 2.3 ± 0.7% in the “older” group. A strong correlation between fat content and T2 was found, while the groups did not significantly differ regarding T2*. Decrease in the MTR could only be shown for the tibialis anterior muscle with age.

Conclusion

Age‐related changes in healthy human calf musculature were found. Further studies might show possible correlations of age‐dependent changes with physical efficiency and susceptibility to diseases like type 2 diabetes. J. Magn. Reson. Imaging 2009;29:1346–1354. © 2009 Wiley‐Liss, Inc.
Diffusion‐weighted imaging of prostate cancer: Correlation between apparent diffusion coefficient values and tumor proliferation
Authors: Wang Xi Zhen , Wang Bin , Gao Zhi Qin , Liu Jin Gang , Liu Zuo Qin , Niu Qing Liang , Sun Zhen Kui , Yuan Yu Xiao
Published: May 2009

Purpose

To investigate whether the apparent diffusion coefficient (ADC) values of prostate cancer (PCa) are able to reflect tumor proliferation.

Materials and Methods

The clinical and pathological information for 38 patients with PCa and 33 patients with benign prostate hyperplasia (BPH) were studied. Examination of the patients was performed using a 1.5 T superconducting magnetic scanner equipped with a pelvic phased‐array multicoil. Diffusion‐weighted images (DWIs) were acquired using an echo‐planar imaging sequence. The ADC values of PCa, BPH, and peripheral zone (PZ) were calculated. The cellularity of PCa was recorded based on hematoxylin and eosin staining. The proliferating cell nuclear antigen (PCNA) was detected using an immunohistochemical technique.

Results

The ADC values of PCa, BPH, and PZ were 49.32 ± 12.68 × 10−5 mm2/s, 86.73 ± 26.75 × 10−5 mm2/s, and 126.25 ± 27.21 × 10−5 mm2/s, respectively. The ADC values of PCa were lower than those of BPH and PZ (P < 0.05). The cellularity and PCNA labeling index (LI) of PCa were higher than those of BPH (P < 0.05). The ADC values of PCa were negatively correlated with those of cellularity and PCNA LI (r = −0.646 and −0.446, respectively; P < 0.05).

Conclusion

The ADC values of PCa can reveal the differences in proliferative activity between PCa and BPH. These values are therefore able to predict the proliferative rate of variously differentiated prostate cancers. J. Magn. Reson. Imaging 2009;29:1360–1366. © 2009 Wiley‐Liss, Inc.
Magnetic resonance imaging for axillary staging in patients with breast cancer
Authors: Mortellaro Vincent E. , Marshall Julia , Singer Lauren , Hochwald Steven N. , Chang Myron , Copeland Edward M. , Grobmyer Stephen R.
Published: May 2009

Purpose

To determine the utility of MRI for assessing axillary lymph node status in patients with breast cancer.

Materials and Methods

A consecutive series of patients who underwent breast MR before surgical management of breast cancer with axillary sampling between 2005 and 2007 were identified. MRs were evaluated for the number of nodes, contrast kinetics, nodal area, and number of nodes with no fatty hilum. Data were analyzed in the context of final breast pathology, sentinel lymph node status, and axillary nodal status. Correlations were analyzed using Kendall's τ‐b test. Reported P values are one‐sided.

Results

Fifty‐six females (median = 58 years) were studied. Sentinel lymph nodes (SLN) were positive in 15/56 patients (27%). All SLN + patients (n = 15) had completion axillary dissection. Extent of nodal disease was 1 (n = 3), 2 (n = 4), >2 (n = 8). Presence of any axillary lymph node with no fatty hilum and the number of nodes with no fatty hilum on MR significantly correlated with pathologic node positivity (P = 0.04); while kinetics, node number, and node size did not correlate.

Conclusion

Breast MR may be useful in the assessment of axillary nodes in patients with breast cancer. J. Magn. Reson. Imaging 2009. © 2009 Wiley‐Liss, Inc.
Shielded dual‐loop resonator for arterial spin labeling at the neck
Authors: Hetzer Stefan , Mildner Toralf , Driesel Wolfgang , Weder Manfred , Möller Harald E.
Published: May 2009

Purpose

To construct a dual‐loop coil for continuous arterial spin labeling (CASL) at the human neck and characterize it using computer simulations and magnetic resonance experiments.

Materials and Methods

The labeling coil was designed as a perpendicular pair of shielded‐loop resonators made from coaxial cable to obtain balanced circular loops with minimal electrical interaction with the lossy tissue. Three different excitation modes depending on the phase shift, Δψ, of the currents driving the two circular loops were investigated including a “Maxwell mode” (Δψ = 0°; ie, opposite current directions in both loops), a “quadrature mode” (Δψ = 90°), and a “Helmholtz mode” (Δψ = 180°; ie, identical current directions in both loops).

Results

Simulations of the radiofrequency field distribution indicated a high inversion efficiency at the locations of the carotid and vertebral arteries. With a 7‐mm‐thick polypropylene insulation, a sufficient distance from tissue was achieved to guarantee robust performance at a local specific absorption rate (SAR) well below legal safety limits. Application in healthy volunteers at 3 T yielded quantitative maps of gray matter perfusion with low intersubject variability.

Conclusion

The coil permits robust labeling with low SAR and minimal sensitivity to different loading conditions. J. Magn. Reson. Imaging 2009;29:1414–1424. © 2009 Wiley‐Liss, Inc.
Time‐resolved three‐dimensional magnetic resonance digital subtraction angiography without contrast material in the brain: Initial investigation
Authors: Hori Masaaki , Shiraga Nobuyuki , Watanabe Yasushi , Aoki Shigeki , Isono Sachiko , Yui Masao , Ohtomo Kuni , Araki Tsutomu
Published: May 2009

Purpose

To evaluate a novel magnetic resonance (MR) angiography (MRA) of three‐dimensional (3D) MR digital subtraction angiography (MRDSA) without contrast material, which is essentially 3D true steady‐state free precession (SSFP) with selected inversion recovery (IR) pulse using multiple cardiac phase acquisitions with a short increment delay in the assessment of normal cranial arteries, as a feasibility study before clinical use.

Materials and Methods

Serial MRA images using 3D MRDSA without contrast material were acquired from 10 healthy volunteers. Visualization of normal cranial arteries with time‐spatial labeling inversion pulse (Time‐SLIP) MRDSA was qualitatively compared with the conventional MRA method, 3D time‐of‐flight (TOF)‐MRA.

Results

In all volunteers, serial 3D MRDSAs containing hemodynamic information were successfully imaged. The results of visualization of the branches of the cranial arteries with Time‐SLIP MRDSA were comparable to those of 3D TOF‐MRA. The mean scores ± standard deviations for normal cerebral arteries (internal carotid arteries, middle cerebral arteries, anterior cerebral arteries, posterior cerebral arteries, and basilar arteries) were 2.4 ± 0.5, 2.3 ± 0.5, 2.0 ± 0.7, 2.3 ± 0.7, and 2.5 ± 0.7, respectively.

Conclusion

Time‐SLIP 3D MRDSA is a simple method for obtaining hemodynamic information. Although more MR sequence improvement is needed, it can play an important role in assessing cranial arteries without contrast material. J. Magn. Reson. Imaging 2009;30:214–218. © 2009 Wiley‐Liss, Inc.
Schwann cell chondroitin sulfate proteoglycan inhibits dorsal root ganglion neuron neurite outgrowth and substrate specificity via a soma and not a growth cone mechanism
Authors: Kuffler Damien P. , Sosa Ivan J. , Reyes Onix
Published: May 2009

Sensory axons do not regenerate into or within the spinal cord because of the presence of the axon regeneration inhibitor chondroitin sulfate proteoglycan (CSPG) on activated astrocytes. In the peripheral nervous system, CSPG associated with denervated Schwann cells retards axon regeneration, but regeneration occurs because the balance of regenerating, inhibiting, and promoting factors favors regeneration. The present experiments were aimed at determining the mechanism by which Schwann cells inhibit adult human dorsal root ganglia (H‐DRG) neuron growth cone elongation and substrate specificity, restricting the growth cones to Schwann cell membranes and inhibiting their growth onto a poly‐l‐lysine/laminin substrate. Neurites of H‐DRG neurons free of soma contact with Schwann cells, or after the Schwann cell membranes' CSPG had been digested, were 11.1‐fold longer than those of neurons in soma contact with untreated Schwann cells. Growth cones of DRG neuron somas without Schwann cell CSPG showed no outgrowth inhibition or substrate specificity. These results indicate that the Schwann cell CSPG influences act via contact with neuron somas but not growth cones. These results suggest that eliminating CSPG associated with Schwann cells within DRG in vivo will make the neurons' growth cones insensitive to the regeneration inhibitory influences of CSPG, allowing them to regenerate through the dorsal root entry zone and into and within the spinal cord, where they can establish appropriate and functional synaptic connections. © 2009 Wiley‐Liss, Inc.
Phospholipid transfer protein reduces phosphorylation of tau in human neuronal cells
Authors: Dong Weijiang , Albers John J. , Vuletic Simona
Published: May 2009

Tau function is regulated by phosphorylation, and abnormal tau phosphorylation in neurons is one of the key processes associated with development of Alzheimer's disease and other tauopathies. In this study we provide evidence that phospholipid transfer protein (PLTP), one of the main lipid transfer proteins in the brain, significantly reduces levels of phosphorylated tau and increases levels of the inactive form of glycogen synthase kinase‐3β (GSK3β) in HCN2 cells. Furthermore, inhibition of phosphatidylinositol‐3 kinase (PI3K) reversed the PLTP‐induced increase in levels of GSK3β phosphorylated at serine 9 (pGSK3βSer9) and partially reversed the PLTP‐induced reduction in tau phosphorylation. We provide evidence that the PLTP‐induced changes are not due to activation of Disabled‐1 (Dab1), insofar as PLTP reduced levels of total and phosphorylated Dab1 in HCN2 cells. We have also shown that inhibition of tyrosine kinase activity of insulin receptor (IR) and/or insulin‐like growth factor 1 (IGF1) receptor (IGFR) reverses the PLTP‐induced increase in levels of phosphorylated Akt (pAktThr308 and pAktSer473), suggesting that PLTP‐mediated activation of the PI3K/Akt pathway is dependent on IR/IGFR receptor tyrosine kinase activity. Our study suggests that PLTP may be an important modulator of signal transduction pathways in human neurons. © 2009 Wiley‐Liss, Inc.
A synoptic analysis of the diurnal cycle of thunderstorm precipitation in Kraków (Southern Poland)
Authors: Twardosz Robert
Published: May 2009

A study was made of the relationships between the diurnal pattern of thunderstorm precipitation in Kraków and the types of air masses and atmospheric fronts prevailing over southern Poland during the period 1951–2006. The results of these investigations contribute to a better understanding of the physical processes taking place in the atmosphere that are associated with convective rainfall and may be used to improve the forecasting of the temporal distribution of convective precipitation. The elementary parameters of the daily precipitation cycle were identified, such as the amplitude and phase of the frequency and total thunderstorm precipitation. A separate analysis was performed of air mass and frontal precipitation. The 24‐h thunderstorm precipitation cycle depends on the synoptic situation that determines the thermal and humidity properties of air masses. There is an afternoon peak in Kraków's general diurnal pattern of thunderstorm precipitation that is primarily linked to cold fronts and to air mass precipitation occurring in polar maritime air. Thunderstorm precipitation linked to warm fronts is less frequent and is concentrated in the evening. Copyright © 2009 Royal Meteorological Society
Early fracture callus displays smooth muscle‐like viscoelastic properties ex vivo: Implications for fracture healing
Authors: McDonald Stuart J. , Dooley Philip C. , McDonald Aaron C. , Schuijers Johannes A. , Ward Alex R. , Grills Brian L.
Published: May 2009

Cells of early, fibrous callus in bone fractures possess much alpha smooth muscle actin. This callus contracts and relaxes; however, active and passive components of its force production have yet to be defined. We aimed to establish whether passive viscoelastic properties of early soft fracture callus are smooth muscle‐like in nature. Under anesthesia one rib was fractured in rats and calluses removed 7 days later for analysis. Urinary bladder detrusor muscle and Achilles tendon were also resected and analyzed. Force production in these tissues was measured using a force transducer when preparations were immersed in calcium‐free Krebs‐Henseleit solution (pH 7.4, 22°C). Viscoelastic responses were measured in each preparation in response to 50 µN increases and decreases in force after achieving basal tissue tension by preconditioning. Callus, bladder, and tendon all displayed varying, reproducible degrees of stress relaxation (SR) and reverse stress relaxation (RSR) (n = 7 for all groups). Hysteresis was observed in callus, with the first SR response significantly larger than that produced in subsequent stretches (p < 0.05). Callus SR responses were greater than tendon (p < 0.001) but less than bladder (p < 0.001). Callus RSR responses were greater than tendon (p < 0.001), but no significant difference was seen between RSR of callus and bladder. We concluded that early, soft callus displayed significant SR and RSR phenomena similar to smooth muscle tissue, and SR and RSR may be important in maintenance of static tension in early callus by promoting osteogenesis and fracture healing. © 2009 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27:1508–1513, 2009
Synthesis of different gold nanostructures by solar radiation and their SERS spectroscopy
Authors: Chen Hongjun , Wang Yuling , Dong Shaojun
Published: May 2009

In this article, a simple and novel photochemical synthesis of different gold nanostructures is proposed using solar radiation. This method is rapid, convenient and of low cost, and can be performed under ambient conditions. By adjusting the concentration of sodium acetate (NaAc), different morphologies of the products can be easily obtained. Without NaAc, the products obtained are mainly polyhedral gold particles; lower concentration of NaAc (0.05 and 0.1 M) accelerates the formation of flowerlike gold nanostructures; while higher concentration of NaAc (0.5 M) facilitates the formation of a variety of gold nanowires and nanobelts. It is found that the morphology change of gold nanaostructures is the result of the synergistic effect of poly(diallyl dimethylammonium) chloride (PDDA), Ac− ions, and the pH value. In addition, the different gold nanostructures thus obtained were used as substrates for surface‐enhanced Raman scattering (SERS) with p‐aminothiophenol (p‐ATP) as the probe molecule. In comparison, the flowerlike gold nanostructures show stronger SERS effect than the other gold nanostructures, which is associated with their unique geometrical shapes providing highly localized electromagnetic (EM) field for the optical enhancement to the probe molecules. These gold nanostructures, with different geometrical shapes, might have potential applications in the areas of photonics, optoelectronics and optical sensing. Copyright © 2009 John Wiley & Sons, Ltd.
Molecular determinants of outcomes: Linking tissue banks to outcomes databases
Authors: Bathe Oliver F.
Published: May 2009

In the past, most outcomes research has focused on defining the clinicopathological determinants of outcomes. More recently, it has become apparent that the molecular features of tumor (as well as the genetic makeup of the patient) significantly influence outcomes, including responsiveness to therapy and prognosis. In view of this, there is a need for more research on the molecular determinants of outcomes. Research biorepositories are important vehicles for this type of research and they could potentially accelerate this work. For biomarker research to affect patient care, it is critical to effectively link patient outcomes data with descriptions of the molecular features of tumors. Effective linkage of outcomes data with tissue banks will dramatically accelerate biomarker research. J. Surg. Oncol. 2009;99:513–516. © 2009 Wiley‐Liss, Inc.
Improving surgical outcomes for patients with cancer: An Australian perspective
Authors: Crowe Philip
Published: May 2009

The quality of surgical outcomes for cancer patients is influenced by multiple factors that must be addressed by both a systemic and an individual surgeon approach. In Australia, like many other countries, changes to the health care system via both federal and state government health care quality agencies are likely to positively impact outcomes for surgical patients. Surgical audit is an important component of quality surgical practice and the most successful surgical audit in Australia is the National Breast Cancer Audit, run by the Royal Australasian College of Surgeons. The audit has helped to document the standard of breast cancer surgery in Australia and New Zealand and in the process identified areas for improvement. J. Surg. Oncol. 2009;99:478–480. © 2009 Wiley‐Liss, Inc.
Using the NCDB for cancer care improvement: An introduction to available quality assessment tools
Authors: Raval Mehul V. , Bilimoria Karl Y. , Stewart Andrew K. , Bentrem David J. , Ko Clifford Y.
Published: May 2009

Improving the quality of cancer care requires high‐quality data, mechanisms to feed back information to hospitals, systems to act on the data, and participation of providers. The purpose of this review is to describe how the National Cancer Database (NCDB) can be utilized to improve the quality of cancer care in the United States through a variety of benchmarking reports and data feedback mechanisms available to hospitals approved by the Commission on Cancer (CoC). J. Surg. Oncol. 2009;99:488–490. © 2009 Wiley‐Liss, Inc.
Blood loss in surgical oncology: Neglected quality indicator?
Authors: Dixon Elijah , Datta Indraneel , Sutherland Francis R. , Vauthey Jean‐Nicolas
Published: May 2009

Quality indicators can be defined as “specific and measurable elements of practice that can be used to assess the quality of care”. Surgical blood loss is one of the most significant perioperative predictors of patient outcome. Blood loss is a modifiable quality indicator for oncologic cancer surgery. Surgical oncologists need to alter their surgical technique to promote bloodless surgery and decrease the variability in reported blood loss and rates of blood transfusion. J. Surg. Oncol. 2009;99:508–512. © 2009 Wiley‐Liss, Inc.
Measuring and reporting on quality in health care: A framework and road map for improving care
Authors: Brien Susan E. , Dixon Elijah , Ghali William A.
Published: May 2009

Quality of care measurement and reporting at the provider, hospital, or health system level has become increasingly common in health systems around the world. Health system performance reports, whether they be confidentially distributed to the provider or made available to the public, are not only used as a stimulus for quality improvement, but can also be used to inform policy, apportion funding, or in rare cases, punish poorly performing providers. In this review, we outline several principles of quality of healthcare measurement and performance reporting, and describe a framework for optimal performance reporting that provides the greatest opportunity for the desired outcome—health system improvement. The quality reporting framework and roadmap that we present invokes opportunities for improving care in the domain of surgical oncology. J. Surg. Oncol. 2009;99:462–466. © 2009 Wiley‐Liss, Inc.
A novel stationary phase based on amino derivatized nanotubes for HPLC separations: Theoretical and practical aspects
Authors: André Claire , Gharbi Tijani , Guillaume Yves‐Claude
Published: May 2009

A novel column based on silica containing immobilized carbon nanotubes (CNTs) was developed and evaluated in terms of its binding efficiency and resolution. First, CNT functionalized with amino groups (CNT‐NH2) were prepared via chemical modification of carboxylic groups introduced on the CNT surface. Secondly the covalent immobilization of CNT‐NH2 was carried out by using glutardialdehyde activating agent on aminopropyl (AP)‐silica surface. This CNT stationary phase was applied to the HPLC separation of two molecule series, i.e. polychlorinated biphenyl (PCB) isomers with different degrees of substitution in the ortho‐position (non‐ortho to tetra‐ortho substituted) and terpenes (linalool, geraniol, thymol, α‐terpineol). The retention behavior of these solute molecules was measured under isocratic conditions with different mobile phase compositions, ranging from 0.05–0.70 v/v of toluene in cyclohexane. The retention factors of the solute molecule do not depend linearly on the toluene fraction but follow a quadratic relationship. This CNT stationary phase was a very useful column for the separation of PCB congeners and terpenes. It was demonstrated that a planar conformation of the solute molecule enhanced the solute retention on this CNT stationary phase. As well, a quantitative structure relationship derived, demonstrated the significant input to retention was due to the structurally selective dipole‐dipole and charge transfer interactions with the solutes. These results were compared with those obtained on the AP stationary phase. The proposed CNT stationary phase for the separation possess distinctive and interesting retentive properties, and chemometric analysis of retention data of appropriate designed series of test solutes appears to be a convenient, objective and quantitative method to prove a new phase specificity.
Use of azobenzene amino acids as photo‐responsive conformational switches to regulate antibody–antigen interaction
Authors: Parisot Judicaël , Kurz Katrin , Hilbrig Frank , Freitag Ruth
Published: May 2009

In an attempt to exploit the large geometry changes associated with azobenzene photo‐isomerization for the modulation of antibody–antigen interaction, we introduced in the backbone of the FLAG peptide (DYKDDDDK), an azobenzene unit to photo‐modulate its conformational states and consequently its interaction with the monoclonal anti‐FLAG‐tag antibody M1. The FLAG‐tag system is an established technique for purifying and detecting the corresponding fusion proteins. In this context, conflicting evidence has been presented regarding the necessity of calcium for stable binding. Using surface plasmon resonance, we showed that not the initial recognition but certainly the stability of the complex improves in the presence of calcium. Subsequently, we substituted two or three of the central aspartate residues for an artificial, azobenzene‐based, photo‐responsive amino acid. Four structural isomers of the artificial amino acid were considered, in total twelve FLAG‐tag analogues were synthesized. Two showed significant differences in their ability to bind to the antibody in their cis versus their trans state. Interestingly, these two peptides are the two shortest of the twelve photo‐peptides investigated. Finally, it was shown that for these two FLAG‐analogues switching between cis and trans states is possible in the presence of the antibody.
An immunoaffinity column with a monoclonal antibody as ligand for human follicle stimulating hormone
Authors: Zandian Marlene , Jungbauer Alois
Published: May 2009

A detailed characterization regarding the chromatographic and biochemical properties of an immunoaffinity column for sample pretreatment using a follicle stimulating hormone (FSH) β‐unit specific mAb has been performed. A maximum binding capacity of approximately 300 μg/mL was determined. A KD value of 4.5×10–8 M could be obtained in batch isotherm measurements. The dynamic binding capacity at 10% did not change when residence time was at least 6 min. High selectivity could be demonstrated using crude culture supernatant from FSH producing Chinese hamster ovary (CHO) cells. A great stability of the matrix was confirmed by performing 100 consecutive chromatographic runs without loss of capacity.
Potential of adsorption isotherm measurements for closer elucidating of binding in chiral liquid chromatographic phase systems
Authors: Samuelsson Jörgen , Arnell Robert , Fornstedt Torgny
Published: May 2009

The human body is a chiral environment and many drugs are chiral and interact differently depending on the type of enantiomer. Therefore, the interest in analytical and preparative separations of enantiomers has steadily increased over the years. LC is today the most important technique in analytical laboratories worldwide. The key to understand the separation system lies in the adsorption isotherm, which describes the equilibrium distribution of solutes between the mobile and stationary phases. By measuring adsorption isotherms in chiral phase systems, a deeper interpenetration concerning enantioselective and non‐selective binding energies and adsorption processes is possible. Furthermore, this data provides the core information needed to optimize preparative chromatographic processes for purification of single enantiomers. However, the measurement of adsorption isotherms is a delicate matter and there are many dangerous pitfalls that may produce erroneous results and even wrong mechanistic conclusions. This review summarizes the most relevant methods and a workflow will be given for avoiding the common pitfalls and obtaining reliable data. Several applications from the literature are also treated to give insight in what information can potentially be obtained from using this methodology.
Does cognitive–behavioral therapy for PTSD improve perceived health and sleep impairment?
Authors: Galovski Tara E. , Monson Candice , Bruce Steven E. , Resick Patricia A.
Published: May 2009

There is a paucity of empirical study about the effects of evidence‐based psychotherapy for posttraumatic stress disorder (PTSD) on concurrent health concerns including sleep impairment. This study compares the differential effects of cognitive processing therapy (CPT) and prolonged exposure (PE) on health‐related concerns and sleep impairment within a PTSD sample of female, adult rape survivors (N = 108). Results showed that participants in both treatments reported lower health‐related concerns over treatment and follow‐up, but there were relatively more improvements in the CPT condition. Examination of sleep quality indicated significant improvement in both CPT and PE across treatment and follow‐up and no significant differences between treatments. These results are discussed with regard to the different mechanisms thought to underlie the treatments and future innovations in PTSD treatment.
Harmonic oscillations in a polymerization
Authors: Katime Issa , Ortiz Juan A. Pérez , Mendizábal Eduardo , Zuluaga Fabio
Published: May 2009

A simple radical polymerization is proposed in this paper, with step‐by‐step chain growth (Ri + M → Ri+1), and termination by transfer to a third body (Ri + S → polymer) such as the solvent. It is assumed that, for a certain critical degree of polymerization n, the propagator Rn reacts with substrate H to produce a deactivator (V) of the first propagator (H + Rn → Rn + V; V + R1 → P1) R1. Assuming that monomer, M, and precursor concentrations are constant, and assuming that the deactivator reaches fast a steady state, the resulting kinetic equations are formally linear, but they admit, perturbations rj(t) of the steady‐state concentrations of the propagators R1, R2, …, Rn, which are periodic functions of time. Even more, they can be purely sinusoidal functions (which have been called “harmonic,” in analogy to the solutions of the well‐known classical harmonic oscillator) with phase shift between perturbations rj(t) = Rj− (Rj)0 and rj+1(t) = Rj+1 − (Rj+1)0. Based on these periodic solutions and aiming to a model as simple as possible, a theoretical analysis is made, resulting in that the minimum value for n would be n = 3. Of course, these harmonic oscillations “driven by trimer” are equally found in the group of all the remaining propagators with polymerization degree higher than 3 (variable Y = ∑ Rj). © 2009 Wiley Periodicals, Inc. Int J Chem Kinet 41: 507–511, 2009
Synthesis of polyetherols with isocyanuric ring. Kinetics and mechanisms of reactions, part 2: Consecutive reaction of ethylene carbonate with isocyanuric acid
Authors: Lubczak Jacek , Węglowska Elwira
Published: May 2009

The kinetics and mechanism of the reaction between isocyanuric acid and ethylene carbonate was studied. The multistep reaction in the presence of potassium carbonate as catalyst leads to polyetherols. The imide and hydroxyl groups of intermediates react with ethylene carbonate by slightly different mechanism and kinetics. The rate constants for these elementary processes were established, and based on these experimental data the mechanism of reaction was proposed. Using the isocyanuric acid and 1,3,5‐tris(2‐hydroxyethyl)isocyanurate, it has been found that the reaction of ethylene carbonate with intermediates occurs via a mixed mechanism. © 2009 Wiley Periodicals, Inc. Int J Chem Kinet 41: 523–531, 2009
Current advances in sunflower oil and its applications
Authors: Garcés Rafael , Martínez‐Force Enrique , Salas Joaquín J. , Venegas‐Calerón Mónica
Published: May 2009

The fatty acid and triacylglycerol composition of a vegetable oil determine its physical, chemical and nutritional properties. The applications of a specific oil depend mainly on its fatty acid composition and the way in which fatty acids are arranged in the glycerol backbone. Minor components, e. g. tocopherols, also modify oil properties such as thermo‐oxidative resistance. Sunflower seed commodity oils predominantly contain linoleic and oleic fatty acids with lower content of palmitic and stearic acids. High‐oleic sunflower oil, which can be considered as a commodity oil, has oleic acid up to around 90%. Additionally, new sunflower varieties with different fatty acids and tocopherols compositions have been selected. Due to these modifications sunflower oils possess new properties and are better adapted for direct home consumption, for the food industry, and for non‐food applications such as biolubricants and biodiesel production.
Development of organic light‐emitting diodes for electro‐optical integrated devices
Authors: Ohmori Y.
Published: May 2009

Organic light‐emitting diodes (OLEDs) are discussed for electro‐optical integrated devices that are used for optical signal transmission. Organic optical devices including polymeric optical fibers are used for optical communication applications to realize polymeric electro‐optical integrated devices. The OLEDs were fabricated by vacuum process, i.e. the organic molecular beam deposition (OMBD) technique or a solution process on a polymeric or a glass substrate, for comparison. Optical signals faster than 100 MHz have been created by applying pulsed voltage directly to the OLED utilizing rubrene doped in 8‐hydoxyquinolinum aluminum (Alq3), as an emissive layer. OLEDs fabricated by solution process utilizing rubrene doped in carrier‐transporting materials have also discussed. OLEDs utilizing polymeric materials by solution process are also fabricated and discussed. Moving‐picture signals are transmitted utilizing both vacuum‐ and solution‐processed OLEDs, respectively.
Adhesion of Human U937 Monocytes to Nitrogen‐Rich Organic Thin Films: Novel Insights into the Mechanism of Cellular Adhesion
Authors: Girard‐Lauriault Pierre‐Luc , Truica‐Marasescu Florina , Petit Alain , Wang Hong T. , Desjardins Patrick , Antoniou John , Mwale Fackson , Wertheimer Michael R.
Published: May 2009

We present a two‐fold study designed to elucidate the adhesion mechanism of human U937 monocytes on novel N‐rich thin films deposited by plasma‐ and VUV photo‐polymerisation, so‐called “PVP:N” materials. It is shown that there exist sharply‐defined (“critical”) surface‐chemical conditions that are necessary to induce cell adhesion. By comparing the film chemistries at the “critical” conditions, we demonstrate the dominant role of primary amines in the cell adhesion mechanism. Quantitative real‐time RT‐PCR experiments using U937 cells that had adhered to PVP:N materials for up to 24 h are presented. The adhesion induces a transient expression of cytokines, markers of macrophage activation, as well as a more sustained expression of PPARγ and ICAM‐I.

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Covalent Immobilization of Subtilisin A onto Thin Films of Maleic Anhydride Copolymers
Authors: Tasso Mariana , Cordeiro Ana L. , Salchert Katrin , Werner Carsten
Published: May 2009

Enzymes cleaving the biopolymer adhesives of fouling organisms are attracting attention for the prevention of biofouling. We report a versatile and robust method to confine the serine protease Subtilisin A (or Subtilisin Carlsberg) to surfaces to be protected against biofouling. The approach consists of the covalent immobilization of the protease onto maleic anhydride copolymer thin film coatings. High‐swelling poly(ethylene‐alt‐maleic anhydride) (PEMA) copolymer layers permitted significantly higher enzyme loadings and activities than compact poly(octadecene‐alt‐maleic anhydride) (POMA) films. Substantial fractions of the immobilized, active enzyme layers were found to be conserved upon storage in deionized water for several hours. Ongoing studies explore the potentialities of the developed bioactive coatings to reduce the adhesion of various fouling organisms.

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Monodisperse, Temperature‐Sensitive Microgels Crosslinked by SiOSi Bonds
Authors: Zhang Jian‐Tao , Pan Chang‐Jiang , Keller Thomas , Bhat Rahila , Gottschaldt Michael , Schubert Ulrich S. , Jandt Klaus D.
Published: May 2009

A series of novel temperature‐sensitive microgels were prepared through precipitation polymerization using MPTMS as the comonomer as well as the crosslinker. APS acted as the initiator to initiate the radical copolymerization of NIPAAm and MPTMS, at the same time, the acid environment resulting from the decomposition of APS catalyzed the hydrolysis/condensation of the siloxane groups to generate crosslinking points. The experimental results revealed that the microgels exhibited temperature sensitivity and the phase transition temperature was approximately 31 °C. An increase of SDS concentration or a decrease of MPTMS content resulted in a reduction of the final hydrodynamic diameters of the microgels.

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Synthesis of Heterotelechelic Poly(ethylene glycol)‐block‐poly(succinimide) Possessing Both Acetal andTert‐Butoxycarbonyl‐amino Terminals with Narrow Molecular Weight Distribution
Authors: Nakanishi Masataka , Kataoka Kazunori
Published: May 2009

A novel heterotelechelic linear block copolymer of poly(ethylene glycol) (PEG) and poly(succinimide) (PSI) possessing both acetal andtert‐butoxycarbonyl‐amino (Boc‐NH) terminals (Acetal‐PEG‐b‐PSI‐NH‐Boc) with a narrow molecular weight distribution (MWD) was successfully prepared by the nucleophilic attack of triethylamine (TEA) to the poly(β‐benzyl L‐aspartate) (PBLA) segment of Acetal‐PEG‐b‐PBLA‐NH‐Boc. Acetal‐PEG‐b‐PBLA‐NH‐Boc with MWD of 1.07 was prepared by living anionic ring‐opening polymerization ofβ‐benzyl L‐aspartateN‐carboxy‐anhydride withα‐acetal‐ω‐amino PEG as a macroinitiator, followed by Boc protection. The subsequent conversion of PBLA segment to PSI was successfully carried out by reacting with the catalytic amount of TEA. The characterization by1H NMR, GPC and IR demonstrates that the formation of poly(succinimide) proceeded completely without any remarkable side reactions. Acetal‐PEG‐b‐PSI‐NH‐Boc thus obtained may have a potential utility as a targetable drug carrier in the field of drug delivery system.
Preparation and Characterization of Polyesterurethane Metallopolymers Containing Transition Metal Ions
Authors: Moroi Gabriela‐Nicoleta
Published: May 2009

Several series of metallopolymers (MP) were synthesized from a MDI‐based polyesterurethane and various transition metal ion species, namely, copper(II), manganese(II), cobalt(II), iron(III) and chromium(III). Each series of MP were prepared by using different initial molar ratios urethane groups/metal ions (U/M). MP were characterized in comparison with the parent polyurethane (PU) by atomic absorption spectrometry (AAS), UV‐vis absorption spectroscopy, FT‐IR spectroscopy, differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), thermogravimetric analysis (TGA) and tensile testing. The transition metal ions form coordination complexes with polyurethane functional groups, the intermolecular complexation resulting in the crosslinking of polymer chains. As a consequence, modifications take place in the original structure of PU, e.g. hydrogen bonding and crystallinity of the hard‐segment domains. MP compared with PU present differences in viscoelastic and mechanical behaviors, which generally indicate the reinforcing effect of metal ions on the polyurethane matrix, as well in thermal stability. It was revealed that each transition metal ion has specific effects on the structure and properties of PU. The implications and mechanisms behind these observations are discussed.
Poly(3‐hexylthiophene)/Poly(methyl methacrylate) Core‐Shell Electrospun Fibers for Sensory Applications
Authors: Kuo Chi‐Ching , Wang Cheng‐Ting , Chen Wen‐Chang
Published: May 2009

New electrospun (ES) sensory fibers consisted of poly(methyl methacrylate) (PMMA) core and poly(3‐hexylthiophene‐2,5‐diyl) (P3HT) shell were successfully prepared using a two‐fluid coaxial electrospinning process. Field‐emission scanning electron microscope (FE‐SEM) studies showed that the prepared ES fibers had diameters of 500–700 nm and worm‐like surface structure of P3HT on the fiber. Red emission fibers were exhibited from the laser confocal microscope. Upon exposed to air under light for two weeks, significant blue‐shifting on both absorption and luminescence spectra was found on the prepared ES fibers. It was probably due to the chain scission occurred in the P3HT and led to the reduced conjugated length. The sensitivity of the ES fibers was much better than that of the spin‐coated P3HT film from the comparison on the variation of photophysical properties. Besides, the EPR result indicated the formation of the P3HT · O2 charge transfer complex (CTC), leading to the fiber conductivity of 10−6 S/cm without an external doping. The present study demonstrates that conjugated polymer based ES core‐shell fibers may have potential applications for oxygen‐sensing devices.