bluuebunny/crossref_metadata_2025 huggingface dataset:
Optical nanolithography using a scanning near-field probe with an integrated light source
Authors: Kingsley James W. , Ray Sumon K. , Adawi Ali M. , Leggett Graham J. , Lidzey David G.
Published: November 2008

An ultracompact near-field optical probe is described that is based on a single, integrated assembly consisting of a gallium nitride (GaN) light-emitting diode (LED), a microlens, and a cantilever assembly containing a hollow pyramidal probe with a subwavelength aperture at its apex. The LED emits ultraviolet light and may be used as a light source for near-field photolithographic exposure. Using this simple device compatible with many commercial atomic force microscope systems, it is possible to form nanostructures in photoresist with a resolution of 35 nm, corresponding to λ/10.
Properties of excited xenon atoms in an alternating current plasma display panel
Authors: Uhm Han S. , Oh Phil Y. , Choi Eun H.
Published: November 2008

The properties of excited xenon atoms in the discharge cells of a plasma display panel are investigated by measuring the excited atom density via laser absorption spectroscopy. The density of the excited xenon atoms in the metastable state increases from zero, reaches its peak, and decreases with time in the discharge cells, as expected from a theoretical model. The profile of an excited xenon atom is also studied in terms of the xenon mole fraction. The typical density of excited xenon atoms in a metastable state is on the order of 1013 atoms/cm3.
High intensity, plasma-induced emission from large area ZnO nanorod array cathodes
Authors: Liao Qingliang , Yang Ya , Xia Liansheng , Qi Junjie , Zhang Yue , Huang Yunhua , Qin Zi
Published: November 2008

High intensity electron emission cathodes based on a well-aligned ZnO nanorod array were fabricated. An investigation of the properties of the plasma and the electron beams produced by ZnO nanorod array cathodes was presented. Intense current electron beams were obtained from the cathodes. At an electric field of 7–8V∕μm and pulse duration of ∼100ns, the highest emission current density reached 76–91A∕cm2. The production mechanism of the electron beams was the plasma-induced emission. The morphology and structure of the ZnO nanorod after the application of the accelerating pulses were characterized. The plasma expanded at a velocity of about 10.7cm∕μs during the pulse interval. Whether the emission currents are high or low, the plasma on the cathode surface were always distributed uniformly. The ZnO nanorod array cathodes are expected to be applied to high power vacuum electronic devices as electron beam sources.
Effects of thermal annealing on noise property and temperature coefficient of resistance of single-walled carbon nanotube films
Authors: Lu Rongtao , Xu Guowei , Wu Judy Z.
Published: November 2008

The effect of thermal annealing on the electrical transport properties of purified and COOH-functionalized single-walled carbon nanotube (SWCNT) films has been investigated and the correlation between the noise property and temperature coefficient of resistance (TCR) has been derived. Thermal annealing has been found highly efficient to improve both noise and TCR properties of the SWCNT films, which is important to applications of SWCNT bolometers. While the improvement may be attributed mainly to the enhanced intertube coupling in the purified SWCNT films, a combined change in both intratube and intertube charge transport is responsible in the case of COOH-functionalized SWCNT films.
Charge detection in graphene quantum dots
Authors: Güttinger J. , Stampfer C. , Hellmüller S. , Molitor F. , Ihn T. , Ensslin K.
Published: November 2008

We report measurements on a graphene quantum dot with an integrated graphene charge detector. The quantum dot device consists of a graphene island (diameter of ∼200 nm) connected to source and drain contacts via two narrow graphene constrictions. From Coulomb diamond measurements a charging energy of 4.3 meV is extracted. The charge detector is based on a 45 nm wide graphene nanoribbon placed approximately 60 nm from the island. We show that resonances in the nanoribbon can be used to detect individual charging events on the quantum dot. The charging induced potential change on the quantum dot causes a steplike change in the current in the charge detector. The relative change in the current ranges from 10% up to 60% for detecting individual charging events.
Optical response from lenslike semiconductor nipple arrays
Authors: Wu H.-M. , Lai C.-M. , Peng L.-H.
Published: November 2008

The authors reported the use of recessive size reduction in self-assembled polystyrene sphere mask with anisotropic etching to form lenslike nipple arrays onto the surface of silicon and gallium nitride. These devices are shown to exhibit a filling factor near to an ideal close-packed condition and paraboloidlike etch profile with slope increased proportionally to the device aspect ratio. Specular reflectivity of less than 3% was observed over the visible spectral range for the 0.35-μm-period nipple-lens arrays. Using two-dimensional rigorous coupled-wave analysis, the latter phenomenon can be ascribed to a gradual index matching mechanism accessed by a high surface-coverage semiconductor nipple array structure.
Carrier concentration dependence of terahertz transmission on conducting ZnO films
Authors: Ma Guohong , Li Dong , Ma Hong , Shen Jie , Wu Chenguo , Ge Jin , Hu Shuhong , Dai Ning
Published: November 2008

With the dc reactive magnetron sputtering method, conducting ZnO thin films with different carrier concentrations on glass substrate were fabricated. The dielectric responses of the ZnO films are characterized with terahertz time-domain spectroscopy. Frequency-dependent conductivity, power absorption, and refractive index are obtained, and the experimental results can be well reproduced with the classic Drude model. Our results reveal that by adjusting the carrier concentration of the ZnO film, the conducting ZnO film can serve as broadband antireflection coatings for substrates and optics in the terahertz frequency range.
Control of oxidation and reduction reactions at HfSiO∕Si interfaces through N exposure or incorporation
Authors: Kamada H. , Tanimura T. , Toyoda S. , Kumigashira H. , Oshima M. , Liu G. L. , Liu Z. , Ikeda K.
Published: November 2008

Using synchrotron-radiation photoemission spectroscopy, we have investigated oxidation and reduction reactions of HfSiO(N)∕Si gate stack structures annealed in a N2 or O2 atmosphere. It is found that both oxidation and reduction reactions can be suppressed by using nitrogen-incorporated HfSiO films in the annealing process at proper partial pressure of N2 gas (PN2∼100Torr). The detailed analysis of “SiO2 equivalent thicknesses” for annealed HfSiO and HfSiON films reveals that ambient N2 gas suppresses only the reduction reaction, while nitrogen atoms incorporated in dielectrics suppress both oxidation and reduction reactions.
Electromigration-induced shock waves on metal thin films
Authors: Bradley R. Mark
Published: November 2008

It is shown that surface electromigration can produce shock waves that retain their form as they propagate on the edge of a single-crystal metal thin film. We explain why these shocks form, determine their velocity, and find their internal structure. If two shocks are present initially, they collide and fuse to form a single shock.
The Political Economy of Retail Change in Chinese Cities
Authors: Wang Enru , Song Jinping
Published: November 2008

Retailing in China has become an important engine driving the nation's economy. Along with the rapid expansion in scale, the retail industry has also experienced profound structural changes in cities. The transformation of the retail sector in large cities like Beijing and Shanghai is characterized by a realignment of ownership structure, diversification of retail functions, the emergence of new retail formats, the increasing concentration of retail capital and rapid expansion of retail chains, and spatial restructuring and retail suburbanization. The transformation not only reflects the changing supply and demand relations and the interaction between retailing and consumption but also is intrinsically connected to the shift in government policies. We present a political-economy perspective to explain the dramatic retail changes that have occurred in Chinese cities. In particular, we discuss the role of the state in retail transformation and in urban and economic development in general. We argue that the concept of ‘developmental state’ and its alternate variants such as ‘local state corporatism’ and ‘entrepreneurial state’ provide valuable and illuminating insights to the understanding of how the Chinese state (and especially the local states) acts in developing the economy in the reform era. Nevertheless, these notions need to be revisited to better recognize the complex and dynamic nature of the Chinese state. Instead, we propose that the Chinese state is better understood as a ‘fragmented developmental state’, which displays a strong progrowth orientation but which also suffers from a fragmented administrative structure, an inconsistent regulatory system, and market-distorting activities in the transformation from a socialist state to a developmental state of its own kind.
Unevenness in Urban Governance: Stadium Building and Downtown Redevelopment in Phoenix, Arizona
Authors: Collins Timothy W
Published: November 2008

I examine sociospatial aspects of urban governance, focusing on the case of a downtown-redevelopment stadium project. In many US central cities, wider political economic processes have led to the formation of governance coalitions guided by the interests of private sector agents. The case of Bank One Ballpark in Phoenix, Arizona, demonstrates how political economic conditions were sources of an uneven bargaining context during the process of project negotiations. Because of this unevenness, interests of profiteers were favored at the expense of others. Organized resistance during each phase of stadium building and concentration of increasing revenues in the hands of fewer business operators reflect uneven consequences. These were desired outcomes of the corporate-led coalition's strategy for expansion through the manipulation of state authority and the exclusionary production of space. I expand the application of urban-regime analysis to examine the role of unevenness in local governance.
Tubulin binding blocks mitochondrial voltage-dependent anion channel and regulates respiration
Authors: Rostovtseva Tatiana K. , Sheldon Kely L. , Hassanzadeh Elnaz , Monge Claire , Saks Valdur , Bezrukov Sergey M. , Sackett Dan L.
Published: November 2008

Regulation of mitochondrial outer membrane (MOM) permeability has dual importance: in normal metabolite and energy exchange between mitochondria and cytoplasm and thus in control of respiration, and in apoptosis by release of apoptogenic factors into the cytosol. However, the mechanism of this regulation, dependent on the voltage-dependent anion channel (VDAC), the major channel of MOM, remains controversial. A long-standing puzzle is that in permeabilized cells, adenine nucleotide translocase (ANT) is less accessible to cytosolic ADP than in isolated mitochondria. We solve this puzzle by finding a missing player in the regulation of MOM permeability: the cytoskeletal protein tubulin. We show that nanomolar concentrations of dimeric tubulin induce voltage-sensitive reversible closure of VDAC reconstituted into planar phospholipid membranes. Tubulin strikingly increases VDAC voltage sensitivity and at physiological salt conditions could induce VDAC closure at <10 mV transmembrane potentials. Experiments with isolated mitochondria confirm these findings. Tubulin added to isolated mitochondria decreases ADP availability to ANT, partially restoring the low MOM permeability (high apparent
K
m
for ADP) found in permeabilized cells. Our findings suggest a previously unknown mechanism of regulation of mitochondrial energetics, governed by VDAC and tubulin at the mitochondria–cytosol interface. This tubulin–VDAC interaction requires tubulin anionic C-terminal tail (CTT) peptides. The significance of this interaction may be reflected in the evolutionary conservation of length and anionic charge in CTT throughout eukaryotes, despite wide changes in the exact sequence. Additionally, tubulins that have lost significant length or anionic character are only found in cells that do not have mitochondria.
Nucleophosmin interacts directly with c-Myc and controls c-Myc-induced hyperproliferation and transformation
Authors: Li Zhaoliang , Boone David , Hann Stephen R.
Published: November 2008

The transcription factor c-Myc is essential for cellular proliferation and is one of the most frequently activated oncogenes, but the molecular mechanism mediating its critical role in transformation is unclear. Like c-Myc, multifunctional nucleophosmin (NPM) is tightly regulated during proliferation and is overexpressed in several different types of cancer. Overexpression of NPM enhances proliferation and oncogene-mediated transformation, but the mechanism mediating these effects is unknown. We examined whether NPM stimulates proliferation and transformation by affecting c-Myc. Here, we show that NPM is essential for the activities of oncogenic c-Myc and that overexpressed NPM dramatically stimulates c-Myc-induced hyperproliferation and transformation. Endogenous and exogenous NPM directly interact with c-Myc and regulate the expression of endogenous c-Myc target genes at the promoter. Therefore, NPM is a key cofactor for the transforming activity of c-Myc and the interaction with c-Myc may mediate the enhancement of proliferation and transformation induced by NPM overexppression.
Incipient criticality in ecological communities
Authors: Zillio Tommaso , Banavar Jayanth R. , Green Jessica L. , Harte John , Maritan Amos
Published: November 2008

In ecology, there have been attempts to establish links between the relative species abundance (RSA), the fraction of species in a community with a given abundance, and a power-law form of the species area relationship (SAR), the dependence of species richness on sampling area. However the SAR and other patterns in ecology often do not exhibit power-law behavior over an appreciable range of scales. This raises the question whether a scaling framework can be applied when the system under analysis does not exhibit power-law behavior. Here, we derive a general finite-size scaling framework applicable to such systems that can be used to identify incipient critical behavior and links the scale dependence of the RSA and the SAR. We confirm the generality of our theory by using data from a serpentine grassland plot, which exhibits a power-law SAR, and the Barro Colorado Island plot in Panama, whose SAR shows deviations from power-law behavior at every scale. Our results demonstrate that scaling provides a model-independent framework for analyzing and unifying ecological data and that, despite the absence of power laws, ecosystems are poised in the vicinity of a critical point.
Polynomial-time quantum algorithm for the simulation of chemical dynamics
Authors: Kassal Ivan , Jordan Stephen P. , Love Peter J. , Mohseni Masoud , Aspuru-Guzik Alán
Published: November 2008

The computational cost of exact methods for quantum simulation using classical computers grows exponentially with system size. As a consequence, these techniques can be applied only to small systems. By contrast, we demonstrate that quantum computers could exactly simulate chemical reactions in polynomial time. Our algorithm uses the split-operator approach and explicitly simulates all electron-nuclear and interelectronic interactions in quadratic time. Surprisingly, this treatment is not only more accurate than the Born–Oppenheimer approximation but faster and more efficient as well, for all reactions with more than about four atoms. This is the case even though the entire electronic wave function is propagated on a grid with appropriately short time steps. Although the preparation and measurement of arbitrary states on a quantum computer is inefficient, here we demonstrate how to prepare states of chemical interest efficiently. We also show how to efficiently obtain chemically relevant observables, such as state-to-state transition probabilities and thermal reaction rates. Quantum computers using these techniques could outperform current classical computers with 100 qubits.
Myc regulates a transcriptional program that stimulates mitochondrial glutaminolysis and leads to glutamine addiction
Authors: Wise David R. , DeBerardinis Ralph J. , Mancuso Anthony , Sayed Nabil , Zhang Xiao-Yong , Pfeiffer Harla K. , Nissim Ilana , Daikhin Evgueni , Yudkoff Marc , McMahon Steven B. , Thompson Craig B.
Published: November 2008

Mammalian cells fuel their growth and proliferation through the catabolism of two main substrates: glucose and glutamine. Most of the remaining metabolites taken up by proliferating cells are not catabolized, but instead are used as building blocks during anabolic macromolecular synthesis. Investigations of phosphoinositol 3-kinase (PI3K) and its downstream effector AKT have confirmed that these oncogenes play a direct role in stimulating glucose uptake and metabolism, rendering the transformed cell addicted to glucose for the maintenance of survival. In contrast, less is known about the regulation of glutamine uptake and metabolism. Here, we report that the transcriptional regulatory properties of the oncogene Myc coordinate the expression of genes necessary for cells to engage in glutamine catabolism that exceeds the cellular requirement for protein and nucleotide biosynthesis. A consequence of this Myc-dependent glutaminolysis is the reprogramming of mitochondrial metabolism to depend on glutamine catabolism to sustain cellular viability and TCA cycle anapleurosis. The ability of Myc-expressing cells to engage in glutaminolysis does not depend on concomitant activation of PI3K or AKT. The stimulation of mitochondrial glutamine metabolism resulted in reduced glucose carbon entering the TCA cycle and a decreased contribution of glucose to the mitochondrial-dependent synthesis of phospholipids. These data suggest that oncogenic levels of Myc induce a transcriptional program that promotes glutaminolysis and triggers cellular addiction to glutamine as a bioenergetic substrate.
Updating of Working Memory: Lingering Bindings
Authors: Oberauer Klaus , Vockenberg Kerstin
Published: November 2008

Three experiments investigated proactive interference and proactive facilitation in a memory-updating paradigm. Participants remembered several letters or spatial patterns, distinguished by their spatial positions, and updated them by new stimuli up to 20 times per trial. Self-paced updating times were shorter when an item previously remembered and then replaced reappeared in the same location than when it reappeared in a different location. This effect demonstrates residual memory for no-longer-relevant bindings of items to locations. The effect increased with the number of items to be remembered. With one exception, updating times did not increase, and recall of final values did not decrease, over successive updating steps, thus providing little evidence for proactive interference building up cumulatively.
DNAM-1 promotes activation of cytotoxic lymphocytes by nonprofessional antigen-presenting cells and tumors
Authors: Gilfillan Susan , Chan Christopher J. , Cella Marina , Haynes Nicole M. , Rapaport Aaron S. , Boles Kent S. , Andrews Daniel M. , Smyth Mark J. , Colonna Marco
Published: November 2008

Natural killer (NK) cells and CD8 T cells require adhesion molecules for migration, activation, expansion, differentiation, and effector functions. DNAX accessory molecule 1 (DNAM-1), an adhesion molecule belonging to the immunoglobulin superfamily, promotes many of these functions in vitro. However, because NK cells and CD8 T cells express multiple adhesion molecules, it is unclear whether DNAM-1 has a unique function or is effectively redundant in vivo. To address this question, we generated mice lacking DNAM-1 and evaluated DNAM-1–deficient CD8 T cell and NK cell function in vitro and in vivo. Our results demonstrate that CD8 T cells require DNAM-1 for co-stimulation when recognizing antigen presented by nonprofessional antigen-presenting cells; in contrast, DNAM-1 is dispensable when dendritic cells present the antigen. Similarly, NK cells require DNAM-1 for the elimination of tumor cells that are comparatively resistant to NK cell–mediated cytotoxicity caused by the paucity of other NK cell–activating ligands. We conclude that DNAM-1 serves to extend the range of target cells that can activate CD8 T cell and NK cells and, hence, may be essential for immunosurveillance against tumors and/or viruses that evade recognition by other activating or accessory molecules.
Prioritizing risk pathways: a novel association approach to searching for disease pathways fusing SNPs and pathways
Authors: Chen Lina , Zhang Liangcai , Zhao Yan , Xu Liangde , Shang Yukui , Wang Qian , Li Wan , Wang Hong , Li Xia
Published: November 2008

Motivation: Complex diseases are generally thought to be under the influence of one or more mutated risk genes as well as genetic and environmental factors. Many traditional methods have been developed to identify susceptibility genes assuming a single-gene disease model (‘single-locus methods’). Pathway-based approaches, combined with traditional methods, consider the joint effects of genetic factor and biologic network context. With the accumulation of high-throughput SNP datasets and human biologic pathways, it becomes feasible to search for risk pathways associated with complex diseases using bioinformatics methods. By analyzing the contribution of genetic factor and biologic network context in KEGG (Kyoto Encyclopedia of Genes and Genomes) pathways, we proposed an approach to prioritize risk pathways for complex diseases: Prioritizing Risk Pathways fusing SNPs and pathways (PRP). A risk-scoring (RS) measurement was used to prioritize risk biologic pathways. This could help to demonstrate the pathogenesis of complex diseases from a new perspective and provide new hypotheses. We introduced this approach to five complex diseases and found that these five diseases not only share common risk pathways, but also have their specific risk pathways, which is verified by literature retrieval.

Availability: Genotype frequencies of five case–control samples were downloaded from the WTCCC online system and the address is https://www.wtccc.org.uk/info/access_to_data_samples.shtml

Contact:  chenlina@ems.hrbmu.edu.cn; lixia@hrbmu.edu.cn

Supplementary information:  Supplementary data are available at Bioinformatics online.
SPY Imaging Assessment Correlates with Transesophageal Echocardiogram Assessment of Ventricular Function during Off-Pump Coronary Artery Bypass Grafting
Authors: Anderson Curtis A. , Kypson Alan P. , Hudson Wes , Ferguson Bruce , Rodriguez Evelio
Published: November 2008

Intraoperative assessment of graft anastomoses is commonly performed after off-pump coronary artery bypass grafting (OPCAB). The SPY imaging system allows intraoperative graft assessment. We document correlation between intraoperative SPY images and wall motion abnormality by transesophageal echocardiogram (TEE) during OPCAB. A 79-year-old female underwent OPCAB. Intraoperative graft patency assessment was performed with the SPY and left ventricular wall motion was assessed by TEE. SPY imaging demonstrated poor flow trough the distal vein graft anastomosis to the posterior descending artery, which correlated with a new posterior wall motion hypokinesis. After graft revision, SPY imaging demonstrated good distal flow and the TEE demonstrated normalization of the left ventricular posterior wall motion. SPY technology allows the surgeon to accurately assess graft patency intraoperatively and allows immediate correction of a technical problem.
Robotic Technology—Probably a Safe Tool for Development of Completely Endoscopic Coronary Revascularization Procedures
Authors: Bonatti Johannes , Schachner Thomas , Bonaros Nikolaos , Rützler Elisabeth , Weidinger Felix , Schistek Roland , Feuchtner Gudrun , Friedrich Guy , Pachinger Otmar , Laufer Günther
Published: November 2008

Background

Totally endoscopic coronary artery bypass grafting (TECAB) requires telemanipulation technologies because attempts using conventional thoracoscopic instrumentation have completely failed. These complex operations require individual and team learning curves and necessitate a stepwise approach. The aim of this study is to assess risk adjusted outcome in robotically assisted coronary artery bypass grafting (CABG) after the first 6 years of application.

Methods

From 2001 to 2007, 177 CABG procedures were performed using the da Vinci system. A low risk patient population [age 59 (31–76) years, EuroSCORE 1 (0–7)] was treated. The following procedures were carried out: endoscopic internal mammary artery takedown in minimally invasive direct coronary artery bypass, Off-pump coronary artery bypass, and CABG (n = 26); robotic suturing of left internal mammary artery to left anterior descending artery anastomoses through sternotomy (n = 32); TECAB on the arrested heart (n = 108); TECAB on the beating heart (n = 11).

Results

There was no hospital mortality, and cumulative risk adjusted mortality plots showed that 2.76 predicted events did not occur. Given 177 event free procedures Clopper Pearson estimations revealed a 95% confidence interval between 0.0% and 2.3% for perioperative mortality.

Conclusions

Introduction of robotic TECAB grafting appears to meet current CABG safety standards. Initial application in low risk patients and a stepwise approach towards completely endoscopic versions of the operation are worthwhile. Despite a high grade of innovation and despite learning curves, perioperative mortality may be lower than predicted.
Surgical Feasibility of the Injection of Fibrin Sealant in Cardiac Fat Pads to Reduce the Incidence of Postoperative Atrial Fibrillation after Coronary Artery Bypass Grafting or Valve Surgery: A Pilot Study
Authors: Chryssagis Konstantinos , Klügl Stefan , Liangos Aris , Gutleben Klaus J. , Brachmann Johannes , Diegeler Anno
Published: November 2008

Objective

Atrial fibrillation (AF) is the most common complication following coronary artery bypass grafting or valve surgery. The autonomic nervous system is an important determinant in the development of AF. We have assessed the role of injection of fibrin sealant (FS) as a method to modify conduction in the fad pads, to mimic temporary denervation and to reduce the incidence of postoperative AF in patients undergoing coronary artery bypass grafting or valve surgery.

Patients and Methods

Twenty eligible patients who underwent coronary bypass grafting or aortic valve surgery in our Institution were included in this pilot – study. Detection of AF after surgical intervention was based on patient symptomatology and on daily electrocardiograms obtained on all patients. Telemetry was used in all patients for the entire hospitalization period.

Results

20% of the studied population (n = 4) developed postoperative AF. At the time of discharge one patient (5%) had persistent AF. Postoperative mortality was 5% (n = 1) and not cardiac related. None of the patients required permanent pacemaker implantation.

Conclusions

This first human study of FS injected into the anterior fad pads following low to moderate risk open heart surgery shows, that this procedure is safe and feasible. Moreover, CM −1 injection appears to reduce the need for postoperative intervention and/or treatment of AF by diminishing its incidence.
Normal Quality of Life after the Cox-Maze Procedure for Atrial Fibrillation
Authors: Melby Spencer J. , Zierer Andreas , Lubahn Jordon G. , Bailey Marci S. , Cox James L. , Schuessler Richard B. , Damiano Ralph J.
Published: November 2008

Objective

Atrial fibrillation (AF) has been shown in numerous studies to significantly decrease patient's quality of life. The Cox-Maze procedure has excellent long-term efficacy in curing AF. However, it is unknown whether this procedure improves long-term quality of life in these patients. The purpose of this study was to examine late quality of life in patients who underwent a lone Cox-Maze procedure.

Methods

Between 1987 and 2003, 163 patients underwent a Cox-Maze procedure for lone AF at our institution. Of these, 68 patients agreed and completed the Medical Outcomes Study Short Form 36 Health Survey. Scores from the age-matched general U.S. population were normalized to a mean of 50 and standard deviation of 10 to facilitate comparison. Collected data were compared with the norm-based score for each domain using a one-sample t test. Four patients were removed from the analysis because of AF recurrence.

Results

There were 52 males (81%). Mean age was 52.6 ± 9.5 years. Preoperatively, 37 patients (58%) had paroxysmal and 25 patients (39%) had persistent or permanent AF. The mean duration of AF before surgery was 9.8 ± 8.2 years. There was no statistical difference in norm-based scores between the Cox-Maze procedure group and the age-matched general U.S. population in any of the eight health domains at a mean follow-up of 8.7 ± 3.7 years.

Conclusion

Our results suggest that the Cox-Maze procedure cures AF in the majority of patients, and that those patients who are cured had a normal quality of life when compared with the general population at late follow-up.
Preoperative Hemoglobin A1c Predicts Sternal Wound Infection after Coronary Artery Bypass Surgery with Bilateral versus Single Internal Thoracic Artery Grafts
Authors: Halkos Michael E. , Thourani Vinod H. , Lattouf Omar M. , Kilgo Patrick , Guyton Robert A. , Puskas John D.
Published: November 2008

Objective

Bilateral internal thoracic artery (BITA) grafting during coronary artery bypass (CABG) improves long-term and event-free survival but may carry a higher risk of wound complications. It is unknown whether preoperative hemoglobin A1c (HbA1c), a measure of long-term glucose control, predicts deep sternal wound infection (DSWI) after BITA grafting.

Methods

Of 6356 consecutive patients who underwent isolated CABG between January 1, 2002 and March 30, 2007 and received at least one internal thoracic artery graft, 5199 (81.8%) had preoperative HbA1c levels obtained. BITA grafting was performed in 622 (9.8%) patients. A propensity score measured each patient's probability of having BITA versus single ITA based on 52 risk factors. The primary endpoint was DSWI. Multivariable logistic models with adjusted odds ratios (AOR) examined the effect of HbA1c, BITA grafting, and their interaction on outcomes, adjusted for the propensity score and postoperative glucose levels.

Results

Patients undergoing BITA grafting with HbA1c ≥7% had a higher incidence of DSWI compared with patients with HbA1c <7% (5.0% vs. 1.4%, P = 0.014). After multivariable adjustment, BITA was associated with an increased risk of DSWI (AOR = 2.84, 95% confidence interval 1.41–5.74) in all patients (P = 0.004). For each unit increase in HbA1c, there was a 31% increased risk of DSWI (AOR = 1.31, 95% CI 1.16–1.49, P < 0.001). Patients with HbA1c ≥7% had 2.88-fold increase in DSWI compared with patients with HbA1c <7%.

Conclusions

Elevated preoperative HbA1c and BITA grafting were significant predictors of DSWI after CABG. Elevated HbA1c level should be considered in the risk/benefit analysis when selecting patients for BITA grafting.
Hybrid Thoracic Stent Graft Repair of a Complex Type B Aortic Dissection in a Patient who Presented Three Weeks after Repair of a Type a Aortic Dissection
Authors: Gaur Puja , Kasirajan Karthikeshwar , Miller Daniel L. , Vassiliades Thomas A.
Published: November 2008

Long-term management after repair of a type A aortic dissection includes aggressive medical therapy and routine surveillance with serial imaging to ensure thrombosis of the false lumen. Retained patency of the false lumen can lead to either the development of a false lumen aneurysm with a subsequent rupture or extension of dissection. Typically such events occur late, usually months after repair, and are treated with either a conventional one-stage open thoracoabdominal repair or a two-stage “elephant trunk” procedure. However, most patients who undergo such procedures experience major complications and the procedure-related mortality rate is high. We present a unique case of a 61-year-old woman who presented with a ruptured type B aortic dissection 3 weeks after repair of a type A aortic dissection. She underwent an emergent thoracotomy and primary repair of the ruptured aorta followed by concomitant arch debranching and thoracic stent graft placement. Simultaneous surgical debranching with a median sternotomy and endovascular repair with stent grafts is an attractive hybrid approach in patients who present with an acute rupture of a false lumen aneurysm soon after initial repair of an aortic dissection, a situation in which a conventional repair is not feasible. This report emphasizes that hybrid thoracic stent graft repair should be considered for such high-risk patients in the near future as it offers them relatively lower morbidity and mortality compared with what is seen with conventional repairs.
Natural selection on gene function drives the evolution of LTR retrotransposon families in the rice genome
Authors: Baucom Regina S. , Estill James C. , Leebens-Mack Jim , Bennetzen Jeffrey L.
Published: November 2008

Although the proliferation of LTR retrotransposons can cause major genomic modification and reorganization, the evolutionary dynamics that affect their frequency in host genomes are poorly understood. We analyzed patterns of genetic variation among LTR retrotransposons from Oryza sativa to investigate the type of selective forces that potentially limit their amplification and subsequent population of a nuclear genome. We performed both intra- and interfamily analyses of patterns of molecular sequence variation across multiple LTR retrotransposon genes. This analysis involved more than 1000 LTR retrotransposon sequences from 14 separate families that varied in both their insertion dates and full-length copy numbers. We uncovered evidence of strong purifying selection across all gene regions, but also indications that rare episodes of positive selection and adaptation to the host genome occur. Furthermore, our results indicate that LTR retrotransposons exhibit different but predictable patterns of sequence variation depending on their date of transposition, suggesting that LTR retrotransposons, regardless of superfamily and family classifications, show similar “life-histories.”
Using gene expression profiling to identify a prognostic molecular spectrum in gliomas
Authors: Shirahata Mitsuaki , Oba Shigeyuki , Iwao‐Koizumi Kyoko , Saito Sakae , Ueno Noriko , Oda Masashi , Hashimoto Nobuo , Ishii Shin , Takahashi June A. , Kato Kikuya
Published: November 2008

Histopathological classification of gliomas is often clinically inadequate due to the diversity of tumors that fall within the same class. The goal of the present study was to identify prognostic molecular features in diffusely infiltrating gliomas using gene expression profiling. We selected 3456 genes expressed in gliomas, including 3012 genes found in a gliomal expressed sequence tag collection. The expression levels of these genes in 152 gliomas (100 glioblastomas, 21 anaplastic astrocytomas, 19 diffuse astrocytomas, and 12 anaplastic oligodendrogliomas) were measured using adapter‐tagged competitive polymerase chain reaction, a high‐throughput reverse transcription–polymerase chain reaction technique. We applied unsupervised and supervised principal component analyses to elucidate the prognostic molecular features of the gliomas. The gene expression data matrix was significantly correlated with the histological grades, oligo‐astro histology, and prognosis. Using 110 gliomas, we constructed a prediction model based on the expression profile of 58 genes, resulting in a scheme that reliably classified the glioblastomas into two distinct prognostic subgroups. The model was then tested with another 42 tissues. Multivariate Cox analysis of the glioblastoma patients using other clinical prognostic factors, including age and the extent of surgical resection, indicated that the gene expression profile was a strong and independent prognostic parameter. The gene expression profiling identified clinically informative prognostic molecular features in astrocytic and oligodendroglial tumors that were more reliable than the traditional histological classification scheme. (Cancer Sci 2009; 100: 165–172)
Molecularly targeted therapy for hepatocellular carcinoma
Authors: Tanaka Shinji , Arii Shigeki
Published: November 2008

Accumulated understanding of the molecular pathways regulating cancer progression has led to the development of novel targeted therapies. Hepatocellular carcinoma (HCC) remains a highly lethal disease that is resistant to conventional cytotoxic chemotherapy and radiotherapy. Unlike conventional chemotherapy, molecular‐targeted agents offer the potential advantages of a relatively high therapeutic window and use in combination with other anticancer strategies without overlapping toxicity. It is hoped that these drugs will become valuable therapeutic tools within the multimodal approach to treating cancer. A recent clinical trial revealed an oral multikinase inhibitor, sorafenib, as the first agent that has demonstrated improved overall survival in patients with advanced HCC. The present review summarizes molecular abnormalities of HCC with a focus on clinical studies, and current status as well as problems of the targeted strategies for HCC. (Cancer Sci 2009; 100: 1–8)
Analysis of CHOP rearrangement in pleomorphic liposarcomas using fluorescence in situ hybridization
Authors: Sugita Shintaro , Seki Kunihiko , Yokozawa Karin , Tochigi Naobumi , Furuta Koh , Hisaoka Masanori , Hashimoto Hiroshi , Shimoda Tadakazu , Hasegawa Tadashi
Published: November 2008

Pleomorphic liposarcoma (PLS) is an aggressive subtype of liposarcoma composed of high‐grade sarcoma with pleomorphic lipoblasts. PLS usually exhibits a heterogeneous histology and sometimes has a myxoid or round cell area similar to myxoid/round cell liposarcomas (MLS/RCs). Using fluorescence in situ hybridization (FISH) analysis, we investigated the existence of CHOP split signals in various histological areas of PLS including the MLS/RC‐like feature and also estimated the distribution of various signals with polyploidy and amplification. Moreover, to detect CHOP fusion transcripts we performed nested reverse transcription‐polymerase chain reaction (RT‐PCR). Seven PLSs and three MLS/RCs were selected for FISH analysis using the locus‐specific indicator CHOP (12q13) dual color, break apart probe (Vysis, USA). The FISH analysis was applied to formalin‐fixed, paraffin‐embedded tissue sections of representative areas in all cases. Six of seven PLS cases showed the CHOP split signal ranging from 0.5% to 3% of counted nuclei, while all cases of MLS/RC exhibited CHOP rearrangement in more than 50% of counted nuclei. All cases of PLS showed a varied distribution of extra signals with polyploidy and amplification in each histological area. No CHOP fusion transcript was found in any case of PLS by nested RT‐PCR. A CHOP rearrangement in PLS should be recognized only as a representative part of complex karyotypes, because the number of cells with split signals was minute compared with that of MLS/RC, and the signals were found in any area despite their histological differences. The cytogenetic background of PLS and that of MLS/RC are obviously different despite histological similarity. (Cancer Sci 2009; 100: 82–87)
Intraductal carcinoma component as a favorable prognostic factor in biliary tract carcinoma
Authors: Ojima Hidenori , Kanai Yae , Iwasaki Motoki , Hiraoka Nobuyoshi , Shimada Kazuaki , Sano Tsuyoshi , Sakamoto Yoshihiro , Esaki Minoru , Kosuge Tomoo , Sakamoto Michiie , Hirohashi Setsuo
Published: November 2008

The aim of this study is to evaluate the prognostic impact of an intraductal carcinoma component and bile duct resection margin status in patients with biliary tract carcinoma. An intraductal carcinoma component was defined as carcinoma within the bile duct outside the main tumor nodule consisting of a subepithelial invasive component. Surgically resected materials from 214 patients were evaluated by histological observations. Seventy‐nine patients (36.9%) with an intraductal carcinoma component infrequently developed large tumors and infrequently showed deep invasion and venous, lymphatic and perineural involvement in the main tumor nodule. An intraductal carcinoma component was inversely correlated with advanced clinical stage, and was shown to be a significantly favorable prognostic factor by both univariate and multivariate analyses. Proximal (hepatic) side bile duct resection margin status was categorized into negative for tumor cells, positive with only an intraductal carcinoma component [R1 (is)], and positive with a subepithelial invasive component (R1). Forty‐five patients (21.0%) with an R1 resection margin had a poorer prognosis than 148 patients (69.2%) with a negative resection margin, whereas 21 patients (9.8%) with an R1 (is) resection margin did not. In patients with an R1 resection margin, the risk of anastomotic recurrence was higher, and the period until anastomotic recurrence was shorter, than in patients with an R1 (is) resection margin. Surgeons should not be persistent in trying to achieve a negative surgical margin when the intraoperative frozen section diagnosis is R1 (is), and can choose a safe surgical procedure to avoid postoperative complications. (Cancer Sci 2009; 100: 62–70)
Intra‐hepatic arterial administration with miriplatin suspended in an oily lymphographic agent inhibits the growth of human hepatoma cells orthotopically implanted in nude rats
Authors: Hanada Mitsuharu , Baba Akemi , Tsutsumishita Yasuyuki , Noguchi Toshihiro , Yamaoka Takashi
Published: November 2008

Miriplatin is a lipophilic platinum complex which contains myristates as leaving groups and diaminocyclohexane as a carrier ligand. In order to examine in vivo the antitumor activities of miriplatin suspended in an oily lymphographic agent (Lipiodol Ultra‐Fluide®, LPD) against human hepatocellular carcinoma (HCC) after the intra‐hepatic arterial administration, we have developed a novel orthotopic model of HCC in which the human hepatoma cell line Li‐7 was successively implanted and maintained in the liver of nude rats. Li‐7 tumors established in nude rat livers displayed a trabecular structure similar to their original morphology, and were exclusively supplied by the hepatic artery, suggesting that they exhibited in part the conditions of human HCC. Miriplatin suspended in LPD (miriplatin/LPD) administered into the hepatic artery of this model dose‐dependently inhibited the growth of Li‐7 tumors without markedly enhancing body weight loss and caused a significant reduction in the growth rate at a dose of 400 µg/head compared to LPD alone. In addition, at the therapeutic dose, miriplatin/LPD as well as cisplatin suspended in LPD (400 µg/head) was shown to be more active than zinostatin stimalamer suspended in LPD (20 µg/head) against Li‐7 tumors after a single intra‐hepatic arterial administration. These results suggest miriplatin to be a suitable candidate for use in transarterial chemoembolization (Cancer Sci 2009; 100: 189–194)
Spa‐1 (Sipa1) and Rap signaling in leukemia and cancer metastasis
Authors: Minato Nagahiro , Hattori Masakazu
Published: November 2008

Although Rap GTPases of the Ras family remained enigmatic for years, extensive studies in this decade have revealed diverse functions of Rap in the control of cell proliferation, differentiation, survival, adhesion, and movement. With the use of genetic engineering strategies, we have uncovered essential roles of Rap signaling in normal lymphohematopoietic cell development as well as its crucial involvement in the development of a wide spectrum of leukemia in manners highly dependent on the contexts of cell lineages. Incidentally, recent results also indicate an important role of Spa‐1, a Rap GTPase‐activating protein, in invasion and metastasis in human cancers. While it is unlikely that Rap can function as a classic oncogene by itself, like Ras, emerging findings unveil crucial involvements of Rap GTPases in the distinct aspects of malignancy, including leukemia genesis and cancer metastasis. (Cancer Sci 2009; 100: 17–23)
Transforming growth factor‐β signaling at the tumor–bone interface promotes mammary tumor growth and osteoclast activation
Authors: Futakuchi Mitsuru , Nannuru Kalyan C. , Varney Michelle L. , Sadanandam Anguraj , Nakao Kimihisa , Asai Kiyofumi , Shirai Tomoyuki , Sato Shin‐ya , Singh Rakesh K.
Published: November 2008

Understanding the cellular and molecular changes in the bone microenvironment is important for developing novel therapeutics to control breast cancer bone metastasis. Although the underlying mechanism(s) of bone metastasis has been the focus of intense investigation, relatively little is known about complex molecular interactions between malignant cells and bone stroma. Using a murine syngeneic model that mimics osteolytic changes associated with human breast cancer, we examined the role of tumor–bone interaction in tumor‐induced osteolysis and malignant growth in the bone microenvironment. We identified transforming growth factor‐β receptor 1 (TGF‐βRI) as a commonly upregulated gene at the tumor‐bone (TB) interface. Moreover, TGF‐βRI expression and activation, analyzed by nuclear localization of phospho‐Smad2, was higher in tumor cells and osteoclasts at the TB interface as compared to the tumor‐alone area. Furthermore, attenuation of TGF‐β activity by neutralizing antibody to TGF‐β or TGF‐βRI kinase inhibitor reduced mammary tumor‐induced osteolysis, TGF‐βRI expression and its activation. In addition, we demonstrate a potential role of TGF‐β as an important modifier of receptor activator of NF‐κB ligand (RANKL)‐dependent osteoclast activation and osteolysis. Together, these studies demonstrate that inhibition of TGF‐βRI signaling at the TB interface will be a therapeutic target in the treatment of breast cancer‐induced osteolysis. (Cancer Sci 2009; 100: 71–81)