bluuebunny/crossref_metadata_2025_split huggingface dataset:
Duplicating a tandem and ovoids distribution with intensity‐modulated radiotherapy: a feasibility study
Authors: Malhotra Harish K. , Avadhani Jaiteerth S. , de Boer Steven F. , Jaggernauth Wainwright , Kuettel Michael R. , Podgorsak Matthew B. 
Published: August 2007

Brachytherapy plays an important role in the definitive treatment of cervical cancers by radiotherapy. In the present study, we investigated whether sliding‐window intensity‐modulated radiation therapy (IMRT) can achieve a pear‐shaped distribution with a similar sharp dose falloff identical to that of brachytherapy. The computed tomography scans of a tandem and ovoid patient were pushed to both a high dose rate (HDR) and an IMRT treatment planning system (TPS) after the rectum, bladder, and left and right femoral heads had been outlined, ensuring identical structures in both planning systems. A conventional plan (7 Gy in 5 fractions, defined as the average dose to the left and right point A) was generated for HDR treatment. The 150%, 125%, 100%, 75%, 50%, and 25% isodose curves were drawn on each slice and then transferred to the IMRT TPS. The 100% isodose envelope from the HDR plan was the target for IMRT planning. A 7‐field IMRT plan using 6‐MV X‐ray beams was generated and compared with the HDR plan using isodose conformity to the target and 125% volume, dose– volume histograms, and integral dose. The resulting isodose distribution demonstrated good agreement between the HDR and IMRT plans in the 100% and 125% isodose range. The dose falloff in the HDR plan was much steeper than that in the IMRT plan, but it also had a substantially higher maximum dose. Integral dose for the target, rectum, and bladder were found to be 6.69 J, 1.07 J, and 1.02 J in the HDR plan; the respective values for IMRT were 3.47 J, 1.79 J, and 1.34 J. Our preliminary results indicate that the HDR dose distribution can be replicated using a standard sliding‐window IMRT dose delivery technique for points lying closer to the three‐dimensional isodose envelope surrounding point A. Differences in radiobiology and patient positioning between the two techniques merit further consideration.PACS: 87.53.Jw
Daily quality assurance phantom for ultrasound image guided radiation therapy
Authors: Drever Laura , Hilts Michelle 
Published: August 2007

A simple phantom was designed, constructed, tested, and clinically implemented for daily quality assurance (QA) of an ultrasound‐image‐guided radiation therapy (US‐IGRT) system, the Restitu Ultrasound system (Resonant Medical, Montreal, QC). The phantom consists of a high signal echogenic background gel surrounding a low signal hypoechoic egg‐shaped target. Daily QA checks involve ultrasound imaging of the phantom and segmenting of the embedded target using the automated tools available on the US‐IGRT system. This process serves to confirm system hardware and software functions and, in particular, accurate determination of the target position. Experiments were conducted to test the stability of the phantom at room temperature, its tissue‐mimicking properties, the reproducibility of target position measurements, and the usefulness of the phantom as a daily QA device. The phantom proved stable at room temperature, exhibited no evidence of bacterial or fungal invasion in 9 months, and showed limited desiccation (resulting in a monthly reduction in ultrasound‐measured volume of approximately 0.2 cm3). Furthermore, the phantom was shown to be nearly tissue‐mimicking, with speed of sound in the phantom estimated to be 0.8% higher than that assumed by the scanner calibration. The phantom performs well in a clinical setting, owing to its light weight and ease of operation. It provides reproducible measures of target position even with multiple users. At our center, the phantom is being used for daily QA of the US‐IGRT system with clinically acceptable tolerances of cm3 on target volume and mm on target position. For routine daily QA, this phantom is a good alternative to the manufacturer‐supplied calibration phantom, and we recommended that that larger phantom be reserved for less frequent, more detailed QA checks and system calibration.PACS numbers: 87.66.Xa, 87.63.Df
First Report of the Emergence of CTX-M-Type Extended-Spectrum β-Lactamases (ESBLs) as the Predominant ESBL Isolated in a U.S. Health Care System
Authors: Lewis James S. , Herrera Monica , Wickes Brian , Patterson Jan E. , Jorgensen James H. 
Published: August 2007

ABSTRACT

CTX-M-type extended-spectrum β-lactamases (ESBLs) have become increasingly common worldwide, with the notable exception of the United States, where TEM- and SHV-type ESBLs have appeared to predominate. We have noted the emergence of ESBLs in our health care system (the University Health System in San Antonio, TX), especially in
Escherichia coli
isolates, that preferentially hydrolyze cefotaxime rather than ceftazidime, suggesting the possibility of CTX-M-type enzymes. Microbiology laboratory records were reviewed to identify ESBL-producing isolates and to compare the diameters of ceftazidime disk diffusion zones of inhibition to cefotaxime zone diameters. All isolates had been initially detected and confirmed using the procedures recommended by the Clinical and Laboratory Standards Institute. A total of 94 stored ESBL-producing isolates recovered between January 2000 and June 2006 (predominately from blood and normally sterile fluids) were retrieved for further study and screened using PCR primers specific for the presence of CTX-M, TEM, and SHV ESBLs. Only small numbers of retained ESBL-producing isolates were available for study in 2000 and 2002. The percentages of available ESBL-producing organisms in the following years were found to produce CTX-M enzymes: 2000, 25%; 2001, 10%; 2002, 0%; 2003, 60%; 2004, 69%; 2005, 89%; and 2006, 70%. The most common CTX-M-type ESBL was CTX-M-15, followed by CTX-M-16, CTX-M-8, and CTX-M-14. Comparing the disk diffusion zone diameters of cefotaxime and ceftazidime was helpful with the initial recognition of CTX-M-producing
E. coli
, which had an average cefotaxime zone diameter 7 mm smaller than the ceftazidime zone. However, comparing ceftazidime and cefotaxime zones for CTX-M-producing
Klebsiella
spp. was not helpful with initial recognition. CTX-M enzymes were also identified in
Proteus mirabilis
,
Enterobacter
spp., and
Morganella morganii
. Based on pulsed-field gel electrophoresis typing of the
E. coli
isolates, the CTX-M-producing isolates did not represent the spread of a single clone in the institution or in the community. In conclusion, CTX-M-type ESBLs are now the most common ESBL type isolated from patients in our health care system and may also be present but unrecognized in other U.S. locales.
Intracellular Metabolism and Persistence of the Anti-Human Immunodeficiency Virus Activity of 2′,3′-Didehydro-3′-Deoxy-4′-Ethynylthymidine, a Novel Thymidine Analog
Authors: Paintsil Elijah , Dutschman Ginger E. , Hu Rong , Grill Susan P. , Lam Wing , Baba Masanori , Tanaka Hiromichi , Cheng Yung-Chi 
Published: August 2007

ABSTRACT
The therapeutic benefits of current antiretroviral therapy are limited by the evolution of drug-resistant virus and long-term toxicity. Novel antiretroviral compounds with activity against drug-resistant viruses are needed. 2′,3′-Didehydro-3′-deoxy-4′-ethynylthymidine (4′-Ed4T), a novel thymidine analog, has potent anti-human immunodeficiency virus (HIV) activity, maintains considerable activity against multidrug-resistant HIV strains, and is less inhibitory to mitochondrial DNA synthesis in cell culture than its progenitor stavudine (D4T). We investigated the intracellular metabolism and anti-HIV activity of 4′-Ed4T. The profile of 4′-Ed4T metabolites was qualitatively similar to that for zidovudine (AZT), with the monophosphate metabolite as the major metabolite, in contrast to that for D4T, with relatively poor formation of total metabolites. The first phosphorylation step for 4′-Ed4T in cells was more efficient than that for D4T but less than that for AZT. The amount of 4′-Ed4T triphosphate (4′-Ed4TTP) was higher than that of AZTTP at 24 h in culture. There was a dose-dependent accumulation of 4′-Ed4T diphosphate and 4′-Ed4TTP on up-regulation of thymidylate kinase and 3-phosphoglycerate kinase expression in Tet-On RKO cells, respectively. The anti-HIV activity of 4′-Ed4T in cells persisted even after 48 h of drug removal from culture in comparison with AZT, D4T, and nevirapine (NVP). The order of increasing persistence of anti-HIV activity of these compounds after drug removal was 4′-Ed4T > D4T > AZT > NVP. In conclusion, with the persistence of 4′-Ed4TTP and persistent anti-HIV activity in cells, we anticipate less frequent dosing and fewer patient compliance issues than for D4T. 4′-Ed4T is a promising antiviral candidate for HIV type 1 chemotherapy.
Synergistic Efficacy of the Combination of ST-246 with CMX001 against Orthopoxviruses
Authors: Quenelle Debra C. , Prichard Mark N. , Keith Kathy A. , Hruby Dennis E. , Jordan Robert , Painter George R. , Robertson Alice , Kern Earl R. 
Published: August 2007

ABSTRACT
The combination of ST-246 and hexadecyloxypropyl-cidofovir or CMX001 was evaluated for synergistic activity in vitro against vaccinia virus and cowpox virus (CV) and in vivo against CV. In cell culture the combination was highly synergistic against both viruses, and the results suggested that combined treatment with these agents might offer superior efficacy in vivo. For animal models, ST-246 was administered orally with or without CMX001 to mice lethally infected with CV. Treatments began 1, 3, or 6 days postinfection using lower dosages than previously used for single-drug treatment. ST-246 was given at 10, 3, or 1 mg/kg of body weight with or without CMX001 at 3, 1, or 0.3 mg/kg to evaluate potential synergistic interactions. Treatment beginning 6 days post-viral inoculation with ST-246 alone only increased the mean day to death at 10 or 3 mg/kg but had no effect on survival. CMX001 alone also had no effect on survival. When the combination of the two drugs was begun 6 days after viral infection using various dosages of the two, a synergistic reduction in mortality was observed. No evidence of increased toxicity was noted with the combination either in vitro or in vivo. These results indicate that combinations of ST-246 and CMX001 are synergistic both in vitro and in vivo and suggest that combination therapy using ST-246 and CMX001 for treatment of orthopoxvirus disease in humans or animals may provide an additional benefit over the use of the two drugs by themselves.
Effects of DNA- and
Mycobacterium bovis
BCG-Based Delivery of the Flt3 Ligand on Protective Immunity to
Mycobacterium tuberculosis
Authors: Triccas James A. , Shklovskaya Elena , Spratt Joanne , Ryan Anthony A. , Palendira Umaimainthan , Fazekas de StGroth Barbara , Britton Warwick J. 
Published: August 2007

ABSTRACT

The control of intracellular pathogens such as
Mycobacterium tuberculosis
is dependent on the activation and maintenance of pathogen-reactive T cells. Dendritic cells (DCs) are the major antigen-presenting cells initiating antimycobacterial T-cell responses in vivo. To investigate if immunization strategies that aim to optimize DC function can improve protective immunity against virulent mycobacterial infection, we exploited the ability of the hematopoietic growth factor Fms-like tyrosine kinase 3 ligand (Flt3L) to expand the number of DCs in vivo. A DNA fusion of the genes encoding murine Flt3L and
M. tuberculosis
antigen 85B stimulated enhanced gamma interferon (IFN-γ) release by T cells and provided better protection against virulent
M. tuberculosis
than DNA encoding the single components. Vaccination of mice with a recombinant
Mycobacterium bovis
BCG strain secreting Flt3L (BCG:Flt3L) led to early expansion of DCs compared to immunization with BCG alone, and this effect was associated with increased stimulation of BCG-reactive IFN-γ-secreting T cells. BCG and BCG:Flt3L provided similar protective efficacies against low-dose aerosol
M. tuberculosis
; however, immunization of immunodeficient mice revealed that BCG:Flt3L was markedly less virulent than conventional BCG. These results demonstrate the potential of in vivo targeting of DCs to improve antimycobacterial vaccine efficacy.
Antigen-Specific Cellular and Humoral Responses Are Induced by Intradermal
Mycobacterium leprae
Infection of the Mouse Ear
Authors: Duthie Malcolm S. , Reece Stephen T. , Lahiri Ramanuj , Goto Wakako , Raman Vanitha S. , Kaplan Juliette , Ireton Greg C. , Bertholet Sylvie , Gillis Thomas P. , Krahenbuhl James L. , Reed Steven G. 
Published: August 2007

ABSTRACT

Leprosy is caused by infection with
Mycobacterium leprae
. The immune response of leprosy patients can be highly diverse, ranging from strong cellular responses accompanied by an apparent deficit of
M. leprae
-specific antibodies to strong humoral responses with a deficit of cell-mediated responses. Leprosy takes many years to manifest, and this has precluded analyses of disease and immune response development in infected humans. In an attempt to better define development of the immune response during leprosy we have developed an
M. leprae
ear infection model. Intradermal inoculation of
M. leprae
into the ear supported not only infection but also the development of a chronic inflammatory response. The inflammatory response was localized, comprising a T-cell infiltration into the ear and congestion of cells in the draining lymph nodes. The development of local chronic inflammation was prevented by rifampin treatment. Importantly, and in contrast to subcutaneous
M. leprae
footpad infection, systemic
M. leprae
-specific gamma interferon and antibody responses were detected following intradermal ear infection. These results indicate the utility of intradermal ear infection for both induction and understanding of the immune response during
M. leprae
infection and the identification or testing of new leprosy treatments.
Helicobacter pyloriInduces CCL20 Expression
Authors: Tomimori Koh , Uema Eriko , Teruya Hiromitsu , Ishikawa Chie , Okudaira Taeko , Senba Masachika , Yamamoto Kazuo , Matsuyama Toshifumi , Kinjo Fukunori , Fujita Jiro , Mori Naoki 
Published: August 2007

ABSTRACTCCL20 attracts immature dendritic cells and memory T cells and plays a role on mucosal surfaces in inflammation. However, whetherHelicobacter pyloriinfection induces CCL20 in human gastric epithelial cells remains to be determined. The aim of this study was to analyze the molecular mechanism ofH. pylori-induced CCL20 expression. Expression of CCL20 mRNA was assessed by reverse transcription-PCR. Five normal and fiveH. pylori-infected gastric tissue samples were stained immunohistochemically for CCL20. A luciferase assay was used to monitor activation of the CCL20 gene promoter, and an electrophoretic mobility shift assay was used to explore the binding of transcription factors to this promoter. The CCL20 expression in epithelial cells ofH. pylori-positive tissues was higher than that inH. pylori-negative tissues.H. pyloriinduced CCL20 expression in gastric epithelial cell lines, and the induction was dependent on an intactcagpathogenicity island. Activation of the CCL20 promoter byH. pylorioccurred through the action of NF-κB. Transfection of IκB kinase and NF-κB-inducing kinase dominant negative mutants inhibitedH. pylori-mediated activation of CCL20. Treatment with an inhibitor of Hsp90 suppressedH. pylori-induced CCL20 mRNA due to deactivation of NF-κB. Collectively, these results suggest thatH. pyloriactivates NF-κB through an intracellular signaling pathway that involves IκB kinase and NF-κB-inducing kinase, leading to CCL20 gene transcription, and that Hsp90 is a crucial regulator ofH. pylori-induced CCL20 expression, presumably contributing to the immune response inH. pylori.
Cause of Damage of Reactive Ion Beam Etching for Ni-Fe films with CO/NH3 and CH3OH Chemicals
Authors: Watanabe Katsuro 
Published: August 2007

The damage caused by reactive ion beam etching (RIBE) using CO/NH3 and CH3OH chemicals was investigated for Ni-Fe films thinner than 20 nm. Measurement of the changes in magnetization of films etched at a stage temperature from 40 to 100ºC and a bias power from 100 to 500 W revealed that the dominant damage with CO/NH3 was chemical, while that with CH3OH was physical. The amount of damage in the latter case was 1/3 to 1/2 that in the former case. The effect of RIBE on the soft magnetic properties was also investigated. A sample etched under conditions that cause a thicker damaged layer had a lower anisotropy field (Hk) and a lower easy axis coercive force (Hc). This indicates that RIBE	degrades magnetic anisotropy in the Ni-Fe films.
Magnetic Abrasive Finishing Using Nano-size Diamond Dispersed Co-Ni Electroless Plated Plastic Balls and its Application to Post CMP Process
Authors: Yoshihara Sachio , Hanzawa Keiko , Shirakashi Takashi 
Published: August 2007

Magnetic Abrasive Particles (MAPs) were successfully prepared by a new technique based on the nickel-cobalt diamond composite plated plastic ball. The finishing results for	Damascene samples proved the powerful ability of the new MAPs for application in fabricating electronic devices. In this report, a new process for the preparation of bound MAPs based on the electroless cobalt-nickel boron diamond composite plating on plastic balls is described. Here, plastic balls were used as a support for the growth of MAPs due to its lightweight properties. This work aims to develop lightweight and forceful MAPs. Magnetic field assisted finishing was performed to examine the fabricated MAPs. The AFM images showed the changes in the surface profile before and after finishing by cobalt-nickel diamond composite plated plastic balls for 10 minutes. The AFM images for the sample after MAF suggest that surface smoothing could be attained and that nano-level polishing could be achieved by this method.
Sources of Error in Dual-Wavelength Radar Remote Sensing of Cloud Liquid Water Content
Authors: Williams John K. , Vivekanandan J. 
Published: August 2007

Abstract
Dual-wavelength ratio (DWR) techniques offer the prospect of producing high-resolution mapping of cloud microphysical properties, including retrievals of cloud liquid water content (LWC) from reflectivity measured by millimeter-wavelength radars. Unfortunately, noise and artifacts in the DWR require smoothing to obtain physically realistic values of LWC with a concomitant loss of resolution. Factors that cause inaccuracy in the retrieved LWC include uncertainty in gas and liquid water attenuation coefficients, Mie scattering due to large water droplets or ice particles, corruption of the radar reflectivities by noise and nonatmospheric returns, and artifacts due to mismatched radar illumination volumes. The error analysis presented here consists of both analytic and heuristic arguments; it is illustrated using data from the Mount Washington Icing Sensors Project (MWISP) and from an idealized simulation. In addition to offering insight into design considerations for a DWR system, some results suggest methods that may mitigate some of these sources of error for existing systems and datasets.
Demonstration Measurements of Water Vapor, Cirrus Clouds, and Carbon Dioxide Using a High-Performance Raman Lidar
Authors: Whiteman David N. , Rush Kurt , Veselovskii Igor , Cadirola Martin , Comer Joseph , Potter John R. , Tola Rebecca 
Published: August 2007

Abstract
Profile measurements of atmospheric water vapor, cirrus clouds, and carbon dioxide using the Raman Airborne Spectroscopic lidar (RASL) during ground-based, upward-looking tests are presented here. These measurements improve upon any previously demonstrated using Raman lidar. Daytime boundary layer profiling of water vapor mixing ratio up to an altitude of approximately 4 km under moist, midsummer conditions is performed with less than 5% random error using temporal and spatial resolution of 2 min and 60–210 m, respectively. Daytime cirrus cloud optical depth and extinction-to-backscatter ratio measurements are made using a 1-min average. The potential to simultaneously profile carbon dioxide and water vapor mixing ratio through the boundary layer and extending into the free troposphere during the nighttime is also demonstrated.
Phase Coding for Range Ambiguity Mitigation in Dual-Polarized Doppler Weather Radars
Authors: Bharadwaj N. , Chandrasekar V. 
Published: August 2007

Abstract
This paper evaluates the retrieval of polarimetric variables when phase-coded waveforms are employed to suppress range overlaid echoes. A phase-coded waveform tags transmitted pulses with a phase code and then decodes the received signal to separate the overlaid echoes. Two methods suggested for separating overlaid echoes use random and systematic phase-coding techniques. In this paper, random phase and systematic phase-coded waveforms are evaluated for dual-polarized operation. The random phased-coded and systematic phase-coded waveforms are known to provide fairly good estimates of the Doppler spectral moments. This paper presents results at S band to quantify the performance of phase-coded waveform in retrieving polarimetric variables. It is shown that the polarimetric variables for both strong and weak trip echoes are estimated with acceptable accuracy.
Detection and Correction of Diurnal Sampling Bias in HIRS/2 Brightness Temperatures
Authors: Jackson Darren L. , Soden Brian J. 
Published: August 2007

Abstract
Diurnal sampling biases arise in the High-Resolution Infrared Radiation Sounder (HIRS) satellite observations because some of the NOAA polar-orbiting satellites drift significantly from their original local observation time. Such bias adversely affects interpretation of these data for climate studies. Twenty-six years of HIRS/2 radiance satellite data (1979–2004) were examined by creating monthly mean gridded data that categorize the observations by local observing time through averaging ascending and descending orbits separately. Corresponding HIRS/2 simulated radiance data from the Geophysical Fluid Dynamics Laboratory (GFDL) climate model were constructed using HIRS/2 satellite sampling and were found to accurately represent the diurnal sampling bias. Correction of the HIRS/2 observations from the observed diurnal sampling bias was using the model simulations of HIRS brightness temperatures to adjust the observed brightness temperatures to the model daily mean. The diurnal bias was found to vary with channel, surface type, latitude, satellite, and cloud cover, but showed little dependence on satellite scan angle. Diurnal bias is most pronounced for ascending orbit observations of the afternoon [1400 local solar time (LST)] satellites with 60°N to 60°S domain averaged brightness temperatures variations up to 0.78 K yr−1. Lower tropospheric temperature and water vapor channels contained the largest bias, and biases over land were more than twice as large as those over the ocean. Brightness temperature adjustments of up to 10 K were needed in the most extreme situations.
Spectral Wave–Turbulence Decomposition
Authors: Bricker Jeremy D. , Monismith Stephen G. 
Published: August 2007

AbstractA new method of wave–turbulence decomposition is introduced, for which the only instrument required is one high-frequency pointwise velocity sensor. This is a spectral method that assumes equilibrium turbulence and no wave–turbulence interaction. Nonetheless, laboratory and field experiments show that the new method produces results in good agreement with the results of established wave–turbulence decomposition methods. Therefore, this spectral method proves useful when neither a synchronized wave gauge, nor a second velocimeter, is available. Furthermore, this study indicates that uncertainty in velocimeter probe orientation is responsible for most of the wave bias occurring in turbulent velocity data, so that an accurate measurement of this orientation makes wave–turbulence decomposition unnecessary.