bluuebunny/crossref_metadata_2025 huggingface dataset:
Human Immunodeficiency Virus-Infected Patients with PriorPneumocystisPneumonia Exhibit Increased Serologic Reactivity to Several Major Surface Glycoprotein Clones
Authors: Daly K. R. , Koch J. V. , Shire N. J. , Levin L. , Walzer P. D.
Published: October 2006

Recombinant clones of the carboxyl terminus of the major surface glycoprotein (MsgC) ofPneumocystis jiroveciiare useful for analyzing serologic responses in humans. However, there is no standardized set of antigens in general use, which could lead to conflicting results. We have previously shown that human immunodeficiency virus type 1 (HIV-1)-infected patients with priorPneumocystispneumonia (PcP+) responded more frequently and more strongly to a clone of MsgC than did HIV-1-infected patients without PcP (PcP−). Here we test three new clones of MsgC to determine the effect of antigenic sequence variation on immune reactivity in blood donors and HIV-infected patients previously analyzed for reactivity to our original MsgC clone. In Western blot analyses, PcP+patients exhibited the highest frequency of reactivity to each MsgC clone, and the frequency of reactivity with all four MsgC clones together was significantly higher in sera from PcP+patients than in sera from the other patient groups. Furthermore, in an enzyme-linked immunosorbent assay we found that the PcP+population had the highest level of reactivity to two of the four clones tested. One of the new clones could distinguish between PcP+and PcP−populations, and two MsgC clones could distinguish blood donors from the other patient populations. The results show that inherent differences in MsgC amino acid sequence can affect recognition by antibodies independently of variations in protein length or patient population, and the utility of a clone depends on its sequence and on the populations tested.
Cell-Mediated Immune Responses to Smallpox Vaccination
Authors: Kim Sung-Han , Yeo Sang-Gu , Cho Jae-Hyun , Kim Hong-Bin , Kim Nam-Joong , Oh Myoung-don , Choe Kang-Won , Jee Youngmee , Cho Haewol
Published: October 2006

We report that vaccine dilution (1:1 or 1:10) and previous vaccinia virus vaccination status had no significant effect on cell-mediated immune responses (i.e., the immediate vaccinia virus-specific gamma interferon-producing T-cell response measured by enzyme-linked immunospot assay) 1 month after smallpox vaccination (Lancy-Vaxina; Berna Biotech, Switzerland).
Amastin Peptide-Binding Antibodies as Biomarkers of Active Human Visceral Leishmaniasis
Authors: Rafati Sima , Hassani Nafiseh , Taslimi Yasaman , Movassagh Hesam , Rochette Annie , Papadopoulou Barbara
Published: October 2006

Amastin surface proteins belong to a large family of developmentally regulated proteins comprising up to 45 members that have recently been discovered in the genus
Leishmania
and are highly similar to the amastin proteins in
Trypanosoma cruzi
. All members of the amastin gene family contain a highly conserved 11-amino-acid (aa) signature at the N terminus, which is unique to the amastin proteins and to the
Trypanosomatidae
family. Recent studies have demonstrated that this region is highly protective in a mouse model. The goal of the present study was to evaluate the potential of the 50-aa N-terminal domain of amastin proteins harboring the conserved 11-aa amastin signature peptide as a relevant immune biomarker of cutaneous leishmaniasis (CL) and visceral leishmaniasis (VL). We report here the amastin-binding total immunoglobulins (IgG) and/or IgG subclasses in the sera of patients at different stages of CL (
n
= 90) and VL (
n
= 41). In CL cases, there is no significant difference in seroreactivities between active, recovered, and nonhealed cases. However, the amastin peptide-reactive antibodies were present at high titers in 19 of 20 sera collected from patients with active VL compared to sera from patients recovered from VL and asymptomatic cases of VL. These data suggest that the amastin signature peptide could represent a relevant biomarker for the serodiagnosis of VL and, most importantly, that it could permit differentiation among the different stages of the disease.
Immune Responses of Elk to Initial and Booster Vaccinations withBrucella abortusStrain RB51 or 19
Authors: Olsen S. C. , Fach S. J. , Palmer M. V. , Sacco R. E. , Stoffregen W. C. , Waters W. R.
Published: October 2006

Previous studies have suggested that currently available brucellosis vaccines induce poor or no protection in elk (Cervus elaphus nelsoni). In this study, we characterized the immunologic responses of elk after initial or booster vaccination withBrucella abortusstrains RB51 (SRB51) and 19 (S19). Elk were vaccinated with saline or 1010CFU of SRB51 or S19 (n= seven animals/treatment) and booster vaccinated with a similar dosage of the autologous vaccine at 65 weeks. Compared to nonvaccinates, elk vaccinated with SRB51 or S19 had greater (P< 0.05) antibody responses to SRB51 or S19 after initial vaccination and after booster vaccination. Compared to nonvaccinated elk, greater (P< 0.05) proliferative responses to autologous antigen after initial vaccination occurred at only a few sample times in SRB51 (6, 14, and 22 weeks) and S19 (22 weeks) treatment groups. In general, proliferative responses of vaccinates to nonautologous antigens did not differ (P> 0.05) from the responses of nonvaccinated elk. Gamma interferon production in response to autologous or nonautologousBrucellaantigens did not differ (P> 0.05) between controls and vaccinates after booster vaccination. Flow cytometric techniques suggested that proliferation occurred more frequently in immunoglobulin M-positive cells, with differences between vaccination and control treatments in CD4+and CD8+subset proliferation detected only at 22 weeks after initial vaccination. After booster vaccination, one technique ([3H]thymidine incorporation) suggested that proliferative responses to SRB51 antigen, but not S19 antigen, were greater (P< 0.05) in vaccinates compared to the responses of nonvaccinates. However, in general, flow cytometric and other techniques failed to detect significant anamnestic responses to autologous or nonautologousBrucellaantigens in S19 or SRB51 vaccinates after booster vaccination. Although some cellular immune responses were detected after initial or booster vaccination of elk with SRB51 or S19, our data suggest that responses tend to be transient and much less robust than previously reported in SRB51-vaccinated cattle (Bos taurus) or bison (Bison bison). These data may explain why the vaccination of elk with S19 and SRB51 induces poor protection against brucellosis.
VECTOR VALUED REPRODUCING KERNEL HILBERT SPACES OF INTEGRABLE FUNCTIONS AND MERCER THEOREM
Authors: CARMELI CLAUDIO , DE VITO ERNESTO , TOIGO ALESSANDRO
Published: October 2006

We characterize the reproducing kernel Hilbert spaces whose elements are p-integrable functions in terms of the boundedness of the integral operator whose kernel is the reproducing kernel. Moreover, for p = 2, we show that the spectral decomposition of this integral operator gives a complete description of the reproducing kernel, extending the Mercer theorem.
Annealing Effect on Structural Defects in Low-Dose Separation-by-Implanted-Oxygen Wafers
Authors: Tamura Masao , Ishimaru Manabu , Hinode Kenji , Tokiguchi Katsumi , Seki Hirohumi , Mori Hirotaro
Published: October 2006

The annealing characteristics of low-dose separation-by-implanted-oxygen (SIMOX) (100) Si have been investigated by transmission electron microscopy (TEM). Samples are prepared by 60, 120, and 210 keV oxygen implantations with doses between 1.0×1017 and 6.0×1017/cm2 at 560 °C, followed by annealing at temperatures between 1000 and 1350 °C for 5 to 60 min in a vacuum of 10-6 Torr. As-implanted layers split into two sublayers during high-temperature annealing. The shallow SiO2 precipitate region is located at around projected range (R
p)/2 instead of damage peak (D
p), while the deep buried oxide layer (BOX) lies at around R
p. Also, during the same annealing stages, cavities and SiO2 precipitates are produced and then dissolved in the near surface region above R
p/2. These experimental results are discussed, referring to the point defect distributions in the substrates obtained by Monte Carlo simulation.
Optimization of Barrier Structure for Strain-Compensated Multiple-Quantum-Well AlGaInP Laser Diodes
Authors: Huang Man-Fang , Sun Yu-Lung
Published: October 2006

A theoretical analysis of a strain-compensated multiple-quantum-well (MQW) AlGaInP laser diode (LD) has been conducted to minimize the operation current and enhance the operation temperature. The effect of the barrier height on the tensile-strain quantum barriers was studied under the same optical confinement and emission wavelength. The simulation results suggest that a more uniform and higher carrier distribution inside the MQW region can be obtained for a lower barrier height owing to the improvement in carrier injection. The performance of the AlGaInP LD is thus improved. However, when the barrier height is too small, higher spontaneous rates in the quantum barrier region deteriorate the LD performance instead. Theoretical analysis shows that an Al composition of 0.1 for the 0.5%-tensile-strain Al
x
Ga
y
In1-x-y
P barrier is the optimal value for strain-compensated MQW AlGaInP LDs.
Characteristics of Liquid-Phase-Deposited TiO2 Film on Hydrogenated Amorphous Silicon
Authors: Lee Ming-Kwei , Lee Hung-Chang , Hsu Chih-Min
Published: October 2006

In this study, titanium oxide films were grown on hydrogenated amorphous silicon by liquid phase deposition with ammonium hexafluoro-titanate and boric acid as sources. The structure of deposited film was amorphous, as examined by X-ray diffraction analysis. The leakage current density of an Al/TiO2/a-Si/p-type Si metal–oxide–semiconductor (MOS) structure can reach 7.35×10-5 A/cm2 under a reverse bias of 0.91 MV/cm. After O2 annealing at a temperature of 350 °C, the leakage current density can be much improved to 5.31×10-6 A/cm2 under the reverse bias of 0.91 MV/cm. The dielectric constant is 8.9 after O2 annealing at 450 °C.
Carbon Incorporation on (1101) Facet of AlGaN in Metal Organic Vapor Phase Epitaxy
Authors: Koide Norikatsu , Hikosaka Toshiki , Honda Yoshio , Yamaguchi Masahito , Sawaki Nobuhiko
Published: October 2006

Using C2H2 as the source material, the incorporation of carbon into a (1101)AlGaN facet was studied in metal organic vapor phase epitaxy. The cathodo luminescence (CL) spectra for the sample surface were dominated by two near-band-edge emission peaks, assigned as a donor bound exciton (DBE) peak and a carbon-related exciton peak. The emission intensity of the carbon related exciton peak was enhanced by carbon doping, and the enhancement was more efficient on the (1101) facets than on the (0001) facet. It was found that more carbon is incorporated in a sample with high Al composition on the (1101) facets. In the case of Mg doping, on the other hand, the optical properties on the (1101) facets are nearly the same as those of the (0001) facet.
Growth Evolution of ZrO2 from Deposited Zr Metal during Thermal Oxidation
Authors: Hsieh Li-Zen , Ko Hong-Hsi , Kuei Ping-Yu , Lee Ching-Yuan
Published: October 2006

This work reveals how oxidation temperature affects the diffusion of Zr, the reaction behavior of oxygen and silicon atoms in the interior stacked layer structure and the corresponding crystalline phase of oxide. The depth distributions of the three important inclusive atoms Zr, O, and Si are experimentally determined.
Effects of Oxygen Addition on Superconductivity of Sn Cluster-Assembled Films
Authors: Kumagai Kengo , Hihara Takehiko , Peng Dong-Liang , Sumiyama Kenji
Published: October 2006

Sn cluster-assembled films have been produced using a plasma-gas-condensation cluster deposition apparatus with and without O2 gas addition in a sputtering chamber. The Sn clusters prepared without O2 gas addition agglomerated on the substrate and formed larger islands. They exhibited a broad superconducting transition below 3.7 K, suggesting that their transition temperature T
c depends on their cluster size. When O2 gas was added to the cluster source, cluster size decreased and the agglomeration was prevented. The Sn cluster-assembled film prepared at an O2 gas flow rate R
O2
=0.05 sccm showed a sharp superconducting transition at T
c=4.0 K, which was higher than the T
c of bulk β-Sn (T
c
b=3.7 K). Magnetization measurements indicated that the Sn cluster-assembled films prepared at R
O2
≤0.1 sccm were type II superconductors.
Numerical Analysis of Triangle-Lattice Alignments Formed by Magnetic Dipole Interactions among Feeble Magnetic Particles under High Magnetic Fields
Authors: Ando Tsutomu , Hirota Noriyuki , Satoh Akira , Beaugnon Eric , Wada Hitoshi
Published: October 2006

We performed a two-dimensional numerical simulation of triangle-lattice alignments formed by feeble magnetic particles with a diameter of 10 µm to 1 mm, where Brownian motion of particles is negligible. To quantitatively evaluate the distance between particles in triangle-lattice structures in which some spacing resulted from the interactions among induced magnetic dipoles, we used a three-body distribution function. It is confirmed that the feeble magnetic particles form a more orderly triangle-lattice structure as the number of particles increases and also particles become smaller, and that the distance between the particles in the triangle-lattice structures is more homogeneous as particles become smaller.
Postdeposition Annealing Effect on Redshift Behavior of Electroluminescence for Polymer Light-Emitting Diodes
Authors: Tu Ming-Lung , Su Yan-Kuin , Lu Wei-Chung
Published: October 2006

In this study, polymer light-emitting diodes (PLEDs) with a 2,3-dibutoxy-1,4-poly(phenylene vinylene) (DBPPV) emissive layer were fabricated. After the PLEDs were fabricated, they were postdeposition annealed (post-annealed) at various temperatures, 90, 120, 180, and 210 °C. It was clear that the anomalous current–voltage phenomenon existed at the annealing temperature below 120 °C. The anomalous current–voltage phenomenon was eliminated by post-annealing at temperature of 120 °C and higher. As shown in the electroluminescent (EL) spectra, redshift behavior was found which was attributable to post-annealing effect on the PLEDs. From the measurement of atomic force microscopic (AFM) images, annealing increased the average roughness of DBPPV films. The refractive indexes of DBPPV films also increased because of thermal annealing. That is, thermal annealing increased the number of interchain interactions of DBPPV films. This result caused the redshift behavior of PLED's EL spectrum.
Experimental Study of Optimum Coupling Efficiency of Double-Series-Coupled Microring Resonator
Authors: Kato Tomoyuki , Goebuchi Yuta , Kokubun Yasuo
Published: October 2006

A double-series-coupled microring resonator can achieve a boxlike spectrum response and is applicable to wavelength selective switches. To realize this, however, it is necessary to optimize the coupling efficiencies between buslines and resonators and between resonators. Thus, we have derived analytical expressions for the optimum coupling efficiencies and have obtained analytically, in our previous work, the critical coupling efficiency. In this study, we experimentally examined the critical condition, and also clarified the correspondence between the critical coupling efficiencies and actual structural parameters of the coupler. From these data, the optimum length of the coupling region was obtained.
New Phase Modulators for Next-Generation Low-Temperature Crystallization Method of Si Films
Authors: Taniguchi Yukio , Katou Tomoya , Hiramatsu Masato , Matsumura Masakiyo
Published: October 2006

A conventional phase modulator having only “holes” (or “bumps”) on a quartz plate has been found to have insufficient depth-of-focus (DOF) characteristics. This poor DOF can be attributed to the phase advancement (or retardation) of the zeroth-order diffracted light wave. This phase effect has been applied to developing two types of modulator: one with a sufficiently large DOF, and the other, a single-plate phase modulator capable of producing a two-dimensional light intensity profile suitable for growing arrays of large grains. It was confirmed experimentally that this single-plate modulator could grow arrays of large grains 5 µm in pitch.
Effect of O2 Flow Concentration during Reactive Sputtering of Ni Oxide Thin Films on Their Electrochemical and Electrochromic Properties in Aqueous Acidic and Basic Electrolyte Solutions
Authors: Abe Yoshio , Lee Se-Hee , Zayim Esra Ozkan , Tracy C. Edwin , Pitts J. Roland , Deb Satyen K.
Published: October 2006

Thin films of Ni oxide were deposited by reactive sputtering in argon/oxygen gas mixtures using O2 flow concentrations ranging from 6 to 100% and their electrochemical and electrochromic properties were examined using dilute acidic (1 M KCl+0.5 mM H2SO4) and basic (1 M KOH) aqueous electrolyte solutions. An electrochromic coloration efficiency of 32±5 cm2/C was obtained for all the Ni oxide films regardless of O2 concentration in both KCl+H2SO4 and KOH. The charge capacity and resultant change in the optical density of the Ni oxide films increased with O2 concentration owing to a decrease in crystal grain size and the resultant increase in the active surface area of the NiO crystal grains. Although the interfacial capacitances of the Ni oxide films in KCl+H2SO4 are 2–3 times less than those in KOH, a maximum change in optical density of 0.57 was obtained in KCl+H2SO4 for a fine-grained Ni oxide film with a thickness of 400 nm sputtered in 100% O2.
Properties of Liquid Crystal Lens with Stacked Structure of Liquid Crystal Layers
Authors: Wang Bin , Ye Mao , Sato Susumu
Published: October 2006

A study of the properties of a liquid crystal (LC) lens with a stacked structure of two LC layers is reported. The lens power is approximately twofold larger than that of the LC lens with a single LC layer. The lens exhibits a good ability for focusing incident light beam, and its RMS wavefront error remains small over an entire focus range. With LC layers of 20 µm thickness, the switching times between foci become smaller than 1 s.
Transflective Liquid Crystal Display with Single Cell Gap in Patterned Vertically Aligned Mode
Authors: Lee You-Jin , Lee Tae-Hee , Jung Jong-Wook , Kim Hak-Rin , Choi Yoonseuk , Kang Sung-Gon , Yang Young-Chol , Shin Seongsik , Kim Jae-Hoon
Published: October 2006

We propose a novel transflective liquid crystal display (LCD) configuration with a single cell gap in a patterned vertically aligned (PVA) mode. In this work, the optical path difference in a single cell gap is simply compensated by introducing pixel electrode structures between transmissive and reflective parts in a PVA mode. In addition, our transflective LCD was constructed with the same optical configuration such as that of polarizers and retardation films over the whole panel area. The simulated and measured electro-optic characteristics in the transmissive and reflective parts of our novel transflective LCD have shown good agreement with each other over the whole gray scale range.
Electrooptics of Transflective Displays with Optically Compensated Bend Mode
Authors: Yao I-An , Ke Hung-Lin , Yang Chiu-Lien , Chen Chueh-Ju , Pang Jia-Pang , Chen Tien-Jung , Wu Jin-Jei
Published: October 2006

A novel transflective display with wide viewing angle and fast response has been designed by association with an optically compensated bend (OCB) liquid crystal mode. By optimizing the parameters of the compensation films and liquid crystal (LC) cell, the normalized voltage dependences of transmittance and reflectance curves coincide, which means that the single driving method can be applied. Moreover, the display shows wide viewing angle characteristics in both transmissive and reflective areas, and these results are verified by Poincaré sphere analysis.
Reduction of Sr in Sr3MoO6 Compounds Melted under Ultralow Oxygen Partial Pressure
Authors: Nishimura Hiroshi , Takashima Hideaki , Hosoya Syoichi , Kanno Yoshinori
Published: October 2006

Sr3MoO6 was melted in Ar atmosphere under an ultralow oxygen partial pressure (ULOPP) of p(O2)=10-20 Pa by a lamp-image furnace at 1830–1900 K. Sr3MoO6 melted in Ar atmosphere was yellow, whereas Sr3MoO6 melted under ULOPP changed from yellow to metallic ash-gray luster. X-ray Photoelectron Spectroscopy analysis showed that the Sr in Sr3MoO6 was strongly reduced chemically to a metallic state and that the binding energy of Mo was shifted to the high-energy side.
Hydroxyapatite Film Formation on Polylactic Acid Plate by Aerosol Beam Irradiation
Authors: Tsukamoto Masahiro , Nakamura Naoyuki , Kitajima Akiko , Morimoto Junji , Abe Nobuyuki , Akedo Jun
Published: October 2006

A coating technology was developed to form hydroxyapatite (HAp) films on polylactic acid (PLA) plates by aerosol beam irradiation. The aerosol beam was composed of HAp particles of submicron size and helium gas. HAp films were produced at incidence angles of 0, 10, 20, and 30°, but the HAp films did not have good adhesion to the PLA plate when incidence angles were 0, 10, and 20°. To increase the adhesion strength between the HAp film and the PLA plate, the HAp film produced on the plate with an incidence angle of 30° was heated in an electric furnace. In vitro assessments using simulated body fluid (SBF) were performed to investigate the bioactivity of the HAp-coated PLA plate. The heat-treated HAp film did not peel off from the plate throughout the SBF test. The surface morphology and the crystallinity of the film produced in the SBF suggest that the HAp-coated PLA plate is bioactive.
Photochemistry of Monolayer CH3I on Ag-Covered TiO2(110) Surface
Authors: Su Chaochin , Chen Chih-Chieng , Tsai Chih-Song , Lin Jong-Liang , Lin Jiing-Chyuan
Published: October 2006

The photochemistry of monolayer methyl iodide (CH3I) on a silver-covered TiO2(110) surface is studied by X-ray photoelectron spectroscopy (XPS). Upon the UV irradiation of CH3I/Ag/TiO2(110) at a cryogenic temperature, methyl iodide undergoes desorption and dissociation. The cross sections for CH3I dissociation and desorption are measured at different photon wavelengths of 251, 290, 312, 364, 403, and 546 nm. The photochemistry of monolayer CH3I on Ag/TiO2(110) is wavelength dependent. While photodissociation is the predominant mechanism for CH3I depletion upon irradiation with large-wavelength lights, the nonthermal photodesorption of molecular CH3I becomes the major process at wavelengths below 312 nm. The desorption of energetic CH3 fragments following CH3I photodissociation is evident. Possible mechanisms for the present photochemistry of CH3I on Ag/TiO2(110) are discussed and compared with those on the Ag(111) and TiO2(110) surfaces.
Experimental Studies of Secondary Electron Emission of TiO2 and Ti
Authors: Iyasu Takeshi , Inoue Masahiko , Yoshikawa Hideki , Shimizu Ryuichi
Published: October 2006

Secondary electron emission yield, δ, was measured as a function of primary electron energy, E
P, using an Auger electron microscope to obtain the δ(E
P) curve of TiO2 for the first time. As a reference, the δ(E
P) curve was also measured for Ti to verify the accuracy of this experiment. The construction of a specific sample holder was carried out for the precise measurement of secondary electron emission. The maximum secondary electron yield δm=1.2 at E
P=260 eV for TiO2 whereas δm=0.9 at E
P=280 eV for Ti.
Characterization of Wavelength Stability of Dispersive Monolithic Double Channel-Cut Monochromator in Order of 10-9
Authors: Fujimoto Zhang
Published: October 2006

To monochromatize an X-ray beam with a stable fixed wavelength from continuous spectrum synchrotron radiation (SR), a dispersive monolithic double channel-cut monochromator (MDCM) of (771) and (771) was designed, and fabricated from a float-zone silicon crystal. A method of adjusting the attitude of the MDCM using a wavelength analyzer was contrived; the stability and bandwidth of the transmitted beam were evaluated by this method. It was confirmed that the central wavelength of the transmitted beam did not change at a detection limit of 5×10-9 within the range of half the intensity of the throughput.
Metallization on Three Dimensions Microstructures Using Photoresist Spray Coating for Microdirect Methanol Fuel Cell
Authors: Ishizuka Masanori , Houjou Hiroaki , Motokawa Shinji , Mizuno Jun , Momma Toshiyuki , Osaka Tetsuya , Shoji Shuichi
Published: October 2006

High-efficientcy micro-electrochemical devices are realized by increasing electrode surface areas while maintaining keeping chip size. The use of three dimensional (3-D) electrodes instead of planar electrodes is effective for this purpose. To realize a metal pattern on 3-D structures, spray coating was utilized and the optimum condition for achieving a good photoresist step coverage was determined. A good step coverage of the photoresist was obtained on the obtuse corner formed by the anisotropic wet etching of (100) silicon and even on the vertical corner formed by deep reactive ion etching (RIE). We applied this method to fabricate a high-performance micro direct methanol fuel cell (µDMFC). An open circuit voltage of 548 mV and a maximum power density of 0.72 mW/cm2 were obtained at room temperature with 2 M methanol.
Parallelizable Simulation of Material Effects of Chemical Shrink Process of Nanolithography
Authors: Li Tsung-Lung , Ting Jyh-Hua , Kung Chung-Yuan
Published: October 2006

A parallelizable simulator of the chemical shrink process of nanolithography is developed to investigate the process dependence on material properties. The chemical shrink process model employed for the simulator includes the cross-linking reaction of the resolution enhancement of lithography assisted by chemical shrink (RELACS) material, the inhibitor deprotection reaction of the chemically amplified (CA) resist, and the photoacid diffusion and trapping in the CA resist and RELACS material. It is found that, in the descending order of their effectiveness on amount of shrinkage, the photoacid trapping and diffusion mechanisms of the RELACS are the most effective ones, the photoacid trapping mechanism of the CA resist is second, the photoacid diffusion mechanism of the CA resist and the cross-linking reaction of the RELACS are third, and the deprotection reaction of the CA resist is the least effective. The interpretations of the dependence of the shrinkage amounts on these mechanisms are also provided on the basis of the simulations.
Noninvasive Temperature Estimation in Oncology Hyperthermia Using Phase Changes in Pulse–Echo Ultrasonic Signals
Authors: Vázquez Mónica , Ramos Antonio , Leija Lorenzo , Vera Arturo
Published: October 2006

An accurate and noninvasive temperature measurement inside phantoms and tissues is important to improve hyperthermia treatment. The use of ultrasonic echo-pulses for this purpose is a promising line of research. In this paper, we propose an alternative method for processing echo-signals received from inner regions in phantoms. Ultrasonic estimation of temperature is carried out using a phase demodulation technique, which gauges the indirect effects in the phase domain of the previously reported time-shifts in the echo position. The potential performance and high sensitivity of this procedure is explained and verified with several simulated examples. Finally, the proposed procedure is applied to the experimental assessment of phase changes with temperature in ultrasonic echoes successively acquired from different milieus. In all cases, the results show good performance and high sensitivity. This is an interesting alternative to measurements in waveforms of the very small delays (nanoseconds) associated with this ultrasonic temperature estimation.
Microfabrication of Silicon Using Self-Assembled Monolayer Resist and Metastable Helium Beam
Authors: Zhang Jianwu , Kurahashi Mitsunori , Suzuki Taku , Sun Xia , Yamauchi Yasushi
Published: October 2006

We herein report on the microfabrication of a Si(111) surface with a negative/positive contrast by atom lithography using a neutral metastable helium atom beam (He-MAB) and a self-assembled monolayer (SAM) of octadecyltrichlorosilane (OTS). The OTS SAM bonded directly to the silicon surface as a resist and was exposed to He-MAB through a stencil mask to yield a latent image in it. Using chemical etching to develop and transfer the latent image directly onto the underlying silicon substrate, a square silicon micromesa and a microwell matrix with a nanoscale edge resolutions of approximately 100 nm on the Si(111) surface were fabricated. The negative/positive patterning mechanism was discussed in terms of the damage of the SAM resist under the irradiation of He-MAB and the possible effects of contamination.
Validation of the wall motion score and myocardial performance indexes as novel techniques to assess cardiac function in mice after myocardial infarction
Authors: Zhang Yan , Takagawa Junya , Sievers Richard E. , Khan Muhammad F. , Viswanathan Mohan N. , Springer Matthew L. , Foster Elyse , Yeghiazarians Yerem
Published: October 2006

The aim of this study was to determine the feasibility and accuracy of wall motion score index (WMSI) and myocardial performance index (MPI) for measuring regional and global left ventricular (LV) function with use of high-resolution echocardiography after myocardial infarction (MI) in mice. In 48 mice, myocardial infarction was induced by ligation in the middle of the left anterior descending coronary artery. Echocardiography was performed under anesthesia at baseline and 1 mo after MI. WMSI was analyzed by a 16-segment model on short-axis views, and wall motion was scored as 1 for normal, 2 for hypokinetic, 3 for akinetic, 4 for dyskinetic, and 5 for aneurysmal. WMSI was calculated as the sum of scores divided by the total number of segments. MPI was calculated on the basis of isovolumetric contraction time (IVCT), isovolumetric relaxation time (IVRT), and ejection time (ET): MPI = (IVCT + IVRT)/ET. We measured LV ejection fraction (LVEF), end-systolic and end-diastolic volumes (ESV and EDV), fractional shortening (FS), and infarct size (IS). LVEF at 4 wk after MI was reduced at 32.8 ± 9.0%. Linear correlation analyses showed that WMSI (1.6 ± 0.3) correlated with LVEF ( r = −0.84, P < 0.0005), FS ( r = −0.43, P = 0.003), and IS (34.3 ± 15.3%, r = 0.86, P < 0.0005). MPI (0.67 ± 0.09) correlated with LVEF ( r = −0.67, P < 0.0005) and IS ( r = 0.72, P < 0.0005). MPI also correlated with mitral inflow velocity ( r = −0.68, P < 0.0005) and deceleration time ( r = −0.42, P = 0.003). Stepwise regression analysis revealed that WMSI was independently associated with IS. IS, FS, mitral inflow velocity, and deceleration time were independent determinants of MPI. In conclusion, echocardiographic assessments of WMSI and MPI in mice are feasible and correlate strongly with two-dimensional measurement of LV function and IS. These novel parameters provide additional noninvasive assessment of regional and global LV function in mice after MI.
Cyclic stretch induces PlGF expression in bronchial airway epithelial cells via nitric oxide release
Authors: Mohammed Kamal A. , Nasreen Najmunnisa , Tepper Robert S. , Antony Veena B.
Published: October 2006

Mechanical strain of lung tissue is an important stimulus for the production of growth factors that are critical for lung growth and development. However, excessive mechanical strain, as may occur during mechanical ventilation, may produce an increase in growth factors that may contribute to lung injury. We hypothesized that mechanical strain of primary bronchial airway epithelial cells (BAEpCs) induced the production of placental growth factor (PlGF), a member of the VEGF family. BAEpCs were cultured on a deformable silicoelastic membrane and exposed to different magnitudes of stretch. Stretch induced PlGF and nitric oxide (NO) production that increased with increasing magnitude of stretch. Stretch also induced PlGF and inducible NO synthase ( iNOS) gene expression. The stretch-induced PlGF production and NO synthesis were attenuated by PD98059, a specific mitogen-activated protein kinase kinase-1 and -2 inhibitor. Inhibition of NO generation by l-NAME or l-NMMA or scavenging NO by carboxy-PTIO prevented stretch-mediated erk1/2 activation. In addition, in unstretched BAEpCs, exogenous NO enhanced erk1/erk2 activation. Our data suggest that mechanical stretch of BAEpCs induces iNOS expression and induces PlGF release in an erk1/2 activation-dependent manner.
Placental restriction of fetal growth reduces size at birth and alters postnatal growth, feeding activity, and adiposity in the young lamb
Authors: De Blasio Miles J. , Gatford Kathryn L. , Robinson Jeffrey S. , Owens Julie A.
Published: October 2006

Intrauterine growth restriction (IUGR) is associated with accelerated growth after birth. Together, IUGR and accelerated growth after birth predict reduced lean tissue mass and increased obesity in later life. Although placental insufficiency is a major cause of IUGR, whether it alters growth and adiposity in early postnatal life is not known. We hypothesized that placental restriction (PR) in the sheep would reduce size at birth and increase postnatal growth rate, fat mass, and feeding activity in the young lamb. PR reduced survival rate and size at birth, with soft tissues reduced to a greater extent than skeletal tissues and relative sparing of head width ( P < 0.05 for all). PR did not alter absolute growth rates (i.e., the slope of the line of best fit for age vs. parameter size from birth to 45 days of age) but increased neonatal fractional growth rates (absolute growth rate relative to size at birth) for body weight (+24%), tibia (+15%) and metatarsal (+18%) lengths, hindlimb (+23%) and abdominal (+19%) circumferences, and fractional growth rates for current weight ( P < 0.05) weekly throughout the first 45 days of life. PR and small size at birth reduced individual skeletal muscle weights and increased visceral adiposity in absolute and relative terms. PR also altered feeding activity, which increased with decreasing size at birth and was predictive of increased postnatal growth and adiposity. In conclusion, PR reduced size at birth and induced catch-up growth postnatally, normalizing weight and length but increasing adiposity in early postnatal life. Increased feeding activity may contribute to these alterations in growth and body composition following prenatal restraint and, if they persist, may lead to adverse metabolic and cardiovascular outcomes in later life.
Tissue compartment-specific role of estrogen receptor subtypes in immune cell cytokine production following trauma-hemorrhage
Authors: Suzuki Takao , Shimizu Tomoharu , Yu Huang-Ping , Hsieh Ya-Ching , Choudhry Mashkoor A. , Schwacha Martin G. , Chaudry Irshad H.
Published: October 2006

Although 17β-estradiol administration following trauma-hemorrhage attenuates plasma cytokines and alteration in immune cell cytokine production, it is not known whether the salutary effects are mediated via estrogen receptor (ER)-α or ER-β. Accordingly, we examined which ER subtype predominantly mediates the salutary effects of 17β-estradiol on systemic inflammatory response/immune cell cytokine production in various tissues following trauma-hemorrhage. Male rats underwent trauma-hemorrhage (mean blood pressure: 40 mmHg for 90 min) and fluid resuscitation. The ER-α agonist propyl pyrazole triol (PPT; 5 μg/kg), the ER-β agonist diarylpropionitrile (DPN; 5 μg/kg), 17β-estradiol (50 μg/kg), or vehicle (10% DMSO) was injected subcutaneously during resuscitation, and various measurements were made 24 h thereafter. 17β-Estradiol or PPT administration following trauma-hemorrhage prevented the increase in plasma IL-6 and IL-10 levels that were observed in vehicle-treated animals. IL-6 and TNF-α production by Kupffer cells increased; however, splenic macrophages (SMΦ), alveolar macrophages (AMΦ), and peripheral blood mononuclear cells (PBMC) had decreased release of these cytokines after trauma-hemorrhage. IL-10 production, however, increased in all macrophage populations. Administration of 17β-estradiol following trauma-hemorrhage prevented all of these alterations. PPT had the same effects as 17β-estradiol on IL-6 and TNF-α production by Kupffer cells and SMΦ, and DPN had the same effects on AMΦ and PBMC. The same effects as 17β-estradiol on IL-10 production were observed by PPT on Kupffer cells and DPN on PBMC. Both agonists were equally effective on SMΦ and AMΦ. Thus ER subtypes have tissue compartment-specific roles in mediating the effects of 17β-estradiol on immune cell functions following trauma-hemorrhage.
Novel Platelet and Vascular Roles for Immunoreceptor Signaling
Authors: Samaha Frederick F. , Kahn Mark L.
Published: October 2006

The immunoreceptor signaling pathway has classically been defined by its role in mediating intracellular signals downstream of immune receptors on circulating cells, but recent studies have revealed new and unexpected roles for this pathway in vascular biology. In platelets the immunoreceptor signaling pathway is coupled to 2 structurally distinct platelet collagen receptors, glycoprotein VI and integrin α2β1, and is required for the activation of platelets after exposure to vessel wall collagen during plaque rupture. During vascular development immunoreceptor signaling is required for proper formation of the lymphatic system, a role that has revealed the contribution of hematopoietic endothelial progenitors to that process. In conjunction with the identification of new biological roles in vascular cell types, new molecular mechanisms of activating this signaling pathway have been discovered, including activation by integrins and immunoreceptor tyrosine activation motifs (ITAMs) on receptors that do not function as part of the immune response. Here we discuss some of these recent findings and their implications for vascular biology and the treatment of human vascular diseases.
Nitric Oxide–Dependent Suppression of Thioredoxin-Interacting Protein Expression Enhances Thioredoxin Activity
Authors: Schulze P. Christian , Liu Heling , Choe Elizabeth , Yoshioka Jun , Shalev Anath , Bloch Kenneth D. , Lee Richard T.
Published: October 2006

Objective—

Cellular redox balance is regulated by enzymatic and nonenzymatic systems and freely diffusible nitric oxide (NO) promotes antioxidative mechanisms. We show the NO-dependent transcriptional regulation of the antioxidative thioredoxin system.

Methods and Results—

Incubation of rat pulmonary artery smooth muscle cells (RPaSMC) with the NO donor compound
S
-nitroso-glutathione (GSNO, 100 μmol/L) suppressed thioredoxin-interacting protein (Txnip), an inhibitor of thioredoxin function, by 71±18% and enhanced thioredoxin reductase 2.7±0.2 fold (n=6; both
P
<0.001 versus control). GSNO increased thioredoxin activity (1.9±0.5-fold after 4 hours;
P
<0.05 versus control). Promoter deletion analysis revealed that NO suppression of Txnip transcription is mediated by
cis
-regulatory elements between −1777 and −1127 bp upstream of the start codon. Hyperglycemia induced Txnip promoter activity (3.9±0.2-fold;
P
<0.001) and abolished NO effects (−37.4±1.0% at 5.6 mmol/L glucose versus 12.4±2.1% at 22.4 mmol/L glucose;
P
<0.05). Immunoprecipitation experiments demonstrated that GSNO stimulation and mutation of thioredoxin at Cys69, a site of nitrosylation, had no effect on the Txnip/thioredoxin interaction.

Conclusions—

NO can regulate cellular redox state by changing expression of Txnip and thioredoxin reductase. This represents a novel antioxidative mechanism of NO independent of posttranslational protein
S
-nitrosylation of thioredoxin.
Retrieving Storm Electric Fields from Aircraft Field Mill Data. Part II: Applications
Authors: Koshak W. J. , Mach D. M. , Christian H. J. , Stewart M. F. , Bateman M. G.
Published: October 2006

The Lagrange multiplier theory developed in Part I of this study is applied to complete a relative calibration of a Citation aircraft that is instrumented with six field mill sensors. When side constraints related to average fields are used, the Lagrange multiplier method performs well in computer simulations. For mill measurement errors of 1 V m−1 and a 5 V m−1 error in the mean fair-weather field function, the 3D storm electric field is retrieved to within an error of about 12%. A side constraint that involves estimating the detailed structure of the fair-weather field was also tested using computer simulations. For mill measurement errors of 1 V m−1, the method retrieves the 3D storm field to within an error of about 8% if the fair-weather field estimate is typically within 1 V m−1 of the true fair-weather field. Using this type of side constraint and data from fair-weather field maneuvers taken on 29 June 2001, the Citation aircraft was calibrated. Absolute calibration was completed using the “pitch down method” developed in Part I, and conventional analyses. The resulting calibration matrices were then used to retrieve storm electric fields during a Citation flight on 2 June 2001. The storm field results are encouraging and agree favorably in many respects with results derived from earlier (iterative) techniques of calibration.
Evidence for an immune barrier after in utero hematopoietic-cell transplantation
Authors: Peranteau William H. , Endo Masayuki , Adibe Obinna O. , Flake Alan W.
Published: October 2006

The competence of the immune system of the developing fetus to act as a barrier to in utero hematopoietic-cell transplantation (IUHCT) has been a source of debate. Until now, comparisons of allogeneic and congenic engraftment have been inconclusive due to methodologic limitations resulting in minimal and inefficient engraftment. In this study, E14 fetal mice received transplants of either allogeneic or congenic bone marrow using a new intravascular technique that allows definitive administration of much higher doses of donor cells. Our results demonstrate that 100% of surviving recipients demonstrate engraftment at 1 week of age, but that 70% of allogeneic recipients lose engraftment by 1 month of age, and 80% ultimately fail to sustain long-term chimerism. In contrast, all congenic recipients maintain stable, long-term, multilineage chimerism. These results strongly support an immune barrier to allogeneic engraftment after IUHCT.
Long-term serial analysis of X-chromosome inactivation patterns and JAK2 V617F mutant levels in patients with essential thrombocythemia show that minor mutant-positive clones can remain stable for many years
Authors: Gale Rosemary E. , Allen Anthony J.R. , Nash Michael J. , Linch David C.
Published: October 2006

Essential thrombocythemia (ET) is heterogeneous with respect to natural history, X-chromosome inactivation patterns (XCIPs), and presence of the V617F mutation in Janus kinase 2 (JAK2). We studied 111 patients with ET; 39% were JAK2 mutant positive, and clone size (percentage mutant JAK2) was concordant with XCIP when constitutive T-cell patterns were taken into account. JAK2 mutant clones were present in both clonal and polyclonal cases as determined by XCIP, and the former had higher mutant JAK2 levels (median 26% versus 16%; P = .001). No change was observed in serial XCIP analysis of 14 polyclonal patients over a median follow-up of 61 months. Furthermore, 18 of 19 mutant-positive patients showed no significant change in mutant JAK2 level over a median follow-up of 47 months. These results suggest that, in many cases of ET, a small stable clone containing a JAK2 mutation can be maintained as a subpopulation for many years.
l-arginine availability regulates T-lymphocyte cell-cycle progression
Authors: Rodriguez Paulo C. , Quiceno David G. , Ochoa Augusto C.
Published: October 2006

l-arginine (l-Arg) plays a central role in several biologic systems including the regulation of T-cell function. l-Arg depletion by myeloid-derived suppressor cells producing arginase I is seen in patients with cancer inducing T-cell anergy. We studied how l-Arg starvation could regulate T-cell–cycle progression. Stimulated T cells cultured in the absence of l-Arg are arrested in the G0-G1phase of the cell cycle. This was associated with an inability of T cells to up-regulate cyclin D3 and cyclin-dependent kinase 4 (cdk4), but not cdk6, resulting in an impaired downstream signaling with a decreased phosphorylation of Rb protein and a low expression and binding of E2F1. Silencing of cyclin D3 reproduced the cell cycle arrest caused by l-Arg starvation. The regulation of cyclin D3 and cdk4 by l-Arg starvation occurs at transcriptional and posttranscriptional levels. Signaling through GCN2 kinase is triggered during amino acid starvation. Experiments demonstrated that T cells from GCN2 knock-out mice did not show a decreased proliferation and were able to up-regulate cyclin D3 when cultured in the absence of l-Arg. These results contribute to the understanding of a central mechanism by which cancer and other diseases characterized by high arginase I production may cause T-cell dysfunction.
Deletion of tetraspanin Cd151 results in decreased pathologic angiogenesis in vivo and in vitro
Authors: Takeda Yoshito , Kazarov Alexander R. , Butterfield Catherine E. , Hopkins Benjamin D. , Benjamin Laura E. , Kaipainen Arja , Hemler Martin E.
Published: October 2006

Tetraspanin protein CD151 is abundant on endothelial cells. To determine whether CD151 affects angiogenesis, Cd151-null mice were prepared. Cd151-null mice showed no vascular defects during normal development or during neonatal oxygen-induced retinopathy. However, Cd151-null mice showed impaired pathologic angiogenesis in other in vivo assays (Matrigel plug, corneal micropocket, tumor implantation) and in the ex vivo aortic ring assay. Cd151-null mouse lung endothelial cells (MLECs) showed normal adhesion and proliferation, but marked alterations in vitro, in assays relevant to angiogenesis (migration, spreading, invasion, Matrigel contraction, tube and cable formation, spheroid sprouting). Consistent with these functional impairments, and with the close, preferential association of CD151 with laminin-binding integrins, Cd151-null MLECs also showed selective signaling defects, particularly on laminin substrate. Adhesion-dependent activation of PKB/c-Akt, e-NOS, Rac, and Cdc42 was diminished, but Raf, ERK, p38 MAP kinase, FAK, and Src were unaltered. In Cd151-null MLECs, connections were disrupted between laminin-binding integrins and at least 5 other proteins. In conclusion, CD151 modulates molecular organization of laminin-binding integrins, thereby supporting secondary (ie, after cell adhesion) functions of endothelial cells, which are needed for some types of pathologic angiogenesis in vivo. Selective effects of CD151 on pathologic angiogenesis make it a potentially useful target for anticancer therapy.