bluuebunny/crossref_metadata_2025_split huggingface dataset:
Conservative treatment of a cervical horizontal root fracture and a complicated crown fracture: a case report
Authors: Belobrov I , Weis MV , Parashos P 
Published: August 2008

AbstractThis case report describes successful long‐term conservative management of a cervical root fracture and a complicated crown fracture of the maxillary central incisors in a 12‐year‐old patient. A mineral trioxide aggregate partial pulpotomy was performed on the maxillary right central incisor, while the maxillary left central incisor was splinted to the neighbouring lateral incisor using an acid‐etch technique. Both teeth remained asymptomatic throughout the 3.5 years of a review period, with the cervical root fracture having mostly healed with the formation of a calcified tissue between the fragments. Two different treatment methods were used for two different injuries that resulted in pulp preservation in both cases. This in turn has provided for normal root development to occur while also allowing for preservation of bone.
Calcium phosphate‐based remineralization systems: scientific evidence?
Authors: Reynolds EC 
Published: August 2008

AbstractDental caries remains a major public health problem in most communities even though the prevalence of disease has decreased since the introduction of fluorides. The focus in caries research has recently shifted to the development of methodologies for the detection of the early stages of caries lesions and the non‐invasive treatment of these lesions. Topical fluoride ions, in the presence of calcium and phosphate ions, promote the formation of fluorapatite in tooth enamel by a process referred to as remineralization. The non‐invasive treatment of early caries lesions by remineralization has the potential to be a major advance in the clinical management of the disease. However, for net remineralization to occur adequate levels of calcium and phosphate ions must be available and this process is normally calcium phosphate limited. In recent times three calcium phosphate‐based remineralization systems have been developed and are now commercially available: a casein phosphopeptide stabilized amorphous calcium phosphate (RecaldentTM (CPP‐ACP), CASRN691364‐49‐5), an unstabilized amorphous calcium phosphate (ACP or EnamelonTM) and a bioactive glass containing calcium sodium phosphosilicate (NovaMinTM). The purpose of this review was to determine the scientific evidence to support a role for these remineralization systems in the non‐invasive treatment of early caries lesions. The review has revealed that there is evidence for an anticariogenic efficacy of the EnamelonTM technology for root caries and for the RecaldentTM technology in significantly slowing the progression of coronal caries and promoting the regression of lesions in randomized, controlled clinical trials. Hence the calcium phosphate‐based remineralization technologies show promise as adjunctive treatments to fluoride therapy in the non‐invasive management of early caries lesions.
Dental caries: a dynamic disease process
Authors: Featherstone JDB 
Published: August 2008

AbstractDental caries is a transmissible bacterial disease process caused by acids from bacterial metabolism diffusing into enamel and dentine and dissolving the mineral. The bacteria responsible produce organic acids as a by‐product of their metabolism of fermentable carbohydrates. The caries process is a continuum resulting from many cycles of demineralization and remineralization. Demineralization begins at the atomic level at the crystal surface inside the enamel or dentine and can continue unless halted with the end‐point being cavitation. There are many possibilities to intervene in this continuing process to arrest or reverse the progress of the lesion. Remineralization is the natural repair process for non‐cavitated lesions, and relies on calcium and phosphate ions assisted by fluoride to rebuild a new surface on existing crystal remnants in subsurface lesions remaining after demineralization. These remineralized crystals are acid resistant, being much less soluble than the original mineral.
Radiation safety issues with positron‐emission/computed tomography simulation for stereotactic body radiation therapy
Authors: Kearns William T. , Urbanic James J. , Hampton Carnell J. , McMullen Kevin P. , Blackstock A. William , Stieber Volker W. , Hinson William H. 
Published: August 2008

Stereotactic body radiation therapy (SBRT) simulations using a Stereotactic Body Frame (SBF: Elekta, Stockholm, Sweden) were expanded to include 18F‐deoxyglucosone positron‐emission tomography (FDG PET) for treatment planning. Because of the length of time that staff members are in close proximity to the patient, concerns arose over the radiation safety issues associated with these simulations. The present study examines the radiation exposures of the staff performing SBRT simulations, and provides some guidance on limiting staff exposure during these simulations. Fifteen patients were simulated with PET/CT using the SBF. Patients were immobilized in the SBF before the FDG was administered. The patients were removed from the frame, injected with FDG, and allowed to uptake for approximately 45 minutes. After uptake, the patients were repositioned in the SBF. During the repositioning, exposure rates were recorded at the patient's surface, at the SBF surface, and at 15 cm, 30 cm, and 1 m from the SBF. Administered dose and the approximate time spent on patient repositioning were also recorded. The estimated dose to staff was compared with the dose to staff performing conventional diagnostic PET studies. The average length of time spent in close proximity to the patient after injection was 11.7 minutes, or more than twice the length of time reported for diagnostic PET staff. That time yielded an estimated average dose to the staff of 26.5mSv per simulation. The annual occupational exposure limit is 50 mSv. Based on dose per simulation, staff would have to perform nearly 1900 SBRT simulations annually to exceed the occupational limit. Therefore, at the current rate of 50–100 simulations annually, the addition of PET studies to SBRT simulations is safe for our staff. However, ALARA (“as low as reasonably achievable”) principles still require some radiation safety considerations during SBRT simulations. The PET/CT‐based SBRT simulations are safe and important for treatment planning that optimizes biologic dose distribution with highly accurate and reproducible target definition.PACS numbers: 87.57.uk, 87.59.bd
Scatter Correction for Heart SPECT images Using TEW method
Authors: Changizi Vahid , Takavar Abbas , Babakhani Azadeh , Sohrabi Mahdi 
Published: August 2008

Radionuclide imaging has the potential to be used in quantitative analysis of the regional function of organs. However, quantification of SPECT images is degraded by many factors such as Compton photon scattering. This could have a destructive effect on clinical reports so it is important to do scatter correction to get better quality SPECT images. We intended to determine how scatter correction with the TEW method can help physicians who look at heart SPECT images, get better reports. This study used the TEW method for scatter correction, which was proposed by Ogawa et al.,(9) using the two narrow windows on either side of the photopeak (20% down and 20% up of the photopeak respectively). Injection of radiopharmaceutical 99mTc was used for medical imaging. In the Shariati Hospital, Tehran, we studied a total of 80 patients with heart disease indications (43 men and 37 women) over the ages of 30–80 years. Contrast and sharpness were considerably improved after scatter correction so physicians could look at defects better. In a few cases scatter correction changed heart defect reports to normal. Using TEW, sensitivity and specificity increased from 86% to 94% and from 61% to 84% respectively. This method was simple to use in clinics.PACS numbers: 87.57.uh
Evaluation of MVCT images with skin collimation for electron beam treatment planning
Authors: Beardmore Allen B. , Rosen Isaac I. , Cheek Dennis A. , Fields Robert S. , Hogstrom Kenneth R. 
Published: August 2008

This study assessed the potential of using megavoltage CT (MVCT) images taken with high density skin collimation in place for electron beam treatment planning. MVCT images were taken using the TomoTherapy Hi‐Art system (TomoTherapy Inc., Madison, WI), and the CT numbers were converted to density by calibrating the Hi‐Art system using an electron density phantom. Doses were computed using MVCT images and kVCT images and compared by calculating dose differences in the uniform dose region , excluding buildup region) and calculating distance‐to‐agreement (DTA) in high dose‐gradient regions (penumbra and distal falloff, 90%–10%). For 9 and 16 MeV electron beams of calculated on a homogeneous CIRS Plastic Water (Computerized Imaging Research Systems Inc., Norfolk, VA) phantom without skin collimation, the maximum dose differences were 2.3% and the maximum DTAs were 2.0 mm for both beams. The same phantom was then MVCT scanned nine times with square skin collimators of Cerrobend on its surface ‐ field sizes of , , and and thicknesses of 6, 8, and 10 mm. Using the Philips Pinnacle3 treatment planning system (Philips Medical Systems, N.A., Bothwell, WA), a treatment plan was created for combinations of electron energies of 6, 9, 12, and 16 MeV and each field size. The same treatment plans were calculated using kVCT images of the phantom with regions‐of‐interest (ROI) manually drawn to duplicate the sizes, shapes, and density of the skin collimators. With few exceptions, the maximum dose differences exceeded and the DTAs exceeded 2 mm. We determined that the dose differences were due to small distortions in the MVCT images created by the high density material and manifested as errors in the phantom CT numbers and in the shape of the skin collimator edges. These results suggest that MVCT images without skin collimation have potential for use in patient electron beam treatment planning. However, the small distortion in images with skin collimation makes them unsuitable for clinical use.PACS: 87.53.Tf, 87.59.Fm, 87.53.Fs
In‐house auto cutoff sensor device for radiotherapy machine to monitor patient movements
Authors: Senthilkumar S , Ramakrishnan V 
Published: August 2008

Radiotherapy is an effective treatment method for cancers. During radiation treatment, a patient must be in the same position from the start to the end of radiation treatment. Patient movements are usually monitored by the radiation technologists through the closed circuit television (CCTV) during treatment. If the patient makes a small movement, it is difficult to be noticed by them. In the present work, a simple patient movement monitoring device (PMMD) is fabricated to monitor the patient movement. It uses an electronic sensing device. It continuously monitors the patient's position while the radiation treatment is in process. The device has been retrospectively tested on 86 patients whose movement and distance were measured. The results show that 24 patients moved 1 cm to 2.5 cm from their initial position during the external beam radiotherapy (EBRT). Hence, the device can potentially be used to control and monitor patient movement during EBRT. In addition, an audible alarm situated at the control panel of the treatment room is provided with this device to alert the radiation technologists. It is an inexpensive, compact device which can be used in any radiotherapy machine. It can prevent patients from being treated in a wrong position and therefore improve the quality of the radiation treatment.PACS Number: 87.53Dq
Adaptation of Aerobically GrowingPseudomonas aeruginosato Copper Starvation
Authors: Frangipani Emanuela , Slaveykova Vera I. , Reimmann Cornelia , Haas Dieter 
Published: August 2008

ABSTRACTRestricted bioavailability of copper in certain environments can interfere with cellular respiration because copper is an essential cofactor of most terminal oxidases. The global response of the metabolically versatile bacterium and opportunistic pathogenPseudomonas aeruginosato copper limitation was assessed under aerobic conditions. Expression ofcioAB(encoding an alternative, copper-independent, cyanide-resistant ubiquinol oxidase) was upregulated, whereas numerous iron uptake functions (including the siderophores pyoverdine and pyochelin) were expressed at reduced levels, presumably reflecting a lower demand for iron by respiratory enzymes. Wild-typeP. aeruginosawas able to grow aerobically in a defined glucose medium depleted of copper, whereas acioABmutant did not grow. Thus,P. aeruginosarelies on the CioAB enzyme to cope with severe copper deprivation. A quadruplecyo cco1 cco2 coxmutant, which was deleted for all known heme-copper terminal oxidases ofP. aeruginosa, grew aerobically, albeit more slowly than did the wild type, indicating that the CioAB enzyme is capable of energy conservation. However, the expression of acioA′-′lacZfusion was less dependent on the copper status in the quadruple mutant than in the wild type, suggesting that copper availability might affectcioABexpression indirectly, via the function of the heme-copper oxidases.
Interplay between Cyclic AMP-Cyclic AMP Receptor Protein and Cyclic di-GMP Signaling in
Vibrio cholerae
Biofilm Formation
Authors: Fong Jiunn C. N. , Yildiz Fitnat H. 
Published: August 2008

ABSTRACT

Vibrio cholerae
is a facultative human pathogen. The ability of
V. cholerae
to form biofilms is crucial for its survival in aquatic habitats between epidemics and is advantageous for host-to-host transmission during epidemics. Formation of mature biofilms requires the production of extracellular matrix components, including
Vibrio
polysaccharide (VPS) and matrix proteins. Biofilm formation is positively controlled by the transcriptional regulators VpsR and VpsT and is negatively regulated by the quorum-sensing transcriptional regulator HapR, as well as the cyclic AMP (cAMP)-cAMP receptor protein (CRP) regulatory complex. Transcriptome analysis of
cyaA
(encoding adenylate cyclase) and
crp
(encoding cAMP receptor protein) deletion mutants revealed that cAMP-CRP negatively regulates transcription of both VPS biosynthesis genes and genes encoding biofilm matrix proteins. Further mutational and expression analysis revealed that cAMP-CRP negatively regulates transcription of
vps
genes indirectly through its action on
vpsR
transcription. However, negative regulation of the genes encoding biofilm matrix proteins by cAMP-CRP can also occur independent of VpsR. Transcriptome analysis also revealed that cAMP-CRP regulates the expression of a set of genes encoding diguanylate cyclases (DGCs) and phosphodiesterases. Mutational and phenotypic analysis of the differentially regulated DGCs revealed that a DGC, CdgA, is responsible for the increase in biofilm formation in the Δ
crp
mutant, showing the connection between of cyclic di-GMP and cAMP signaling in
V. cholerae
.
Insights into the Environmental Resistance Gene Pool from the Genome Sequence of the Multidrug-Resistant Environmental Isolate
Escherichia coli
SMS-3-5
Authors: Fricke W. Florian , Wright Meredith S. , Lindell Angela H. , Harkins Derek M. , Baker-Austin Craig , Ravel Jacques , Stepanauskas Ramunas 
Published: August 2008

ABSTRACT

The increasing occurrence of multidrug-resistant pathogens of clinical and agricultural importance is a global public health concern. While antimicrobial use in human and veterinary medicine is known to contribute to the dissemination of antimicrobial resistance, the impact of microbial communities and mobile resistance genes from the environment in this process is not well understood. Isolated from an industrially polluted aquatic environment,
Escherichia coli
SMS-3-5 is resistant to a record number of antimicrobial compounds from all major classes, including two front-line fluoroquinolones (ciprofloxacin and moxifloxacin), and in many cases at record-high concentrations. To gain insights into antimicrobial resistance in environmental bacterial populations, the genome of
E. coli
SMS-3-5 was sequenced and compared to the genome sequences of other
E. coli
strains. In addition, selected genetic loci from
E. coli
SMS-3-5 predicted to be involved in antimicrobial resistance were phenotypically characterized. Using recombinant vector clones from shotgun sequencing libraries, resistance to tetracycline, streptomycin, and sulfonamide/trimethoprim was assigned to a single mosaic region on a 130-kb plasmid (pSMS35_130). The remaining plasmid backbone showed similarity to virulence plasmids from avian-pathogenic
E. coli
(APEC) strains. Individual resistance gene cassettes from pSMS35_130 are conserved among resistant bacterial isolates from multiple phylogenetic and geographic sources. Resistance to quinolones was assigned to several chromosomal loci, mostly encoding transport systems that are also present in susceptible
E. coli
isolates. Antimicrobial resistance in
E. coli
SMS-3-5 is therefore dependent both on determinants acquired from a mobile gene pool that is likely available to clinical and agricultural pathogens, as well, and on specifically adapted multidrug efflux systems. The association of antimicrobial resistance with APEC virulence genes on pSMS35_130 highlights the risk of promoting the spread of virulence through the extensive use of antibiotics.
The prevalence and the causes of minimal intestinal lesions in patients complaining of symptoms suggestive of enteropathy: a follow-up study: Table 1
Authors: Biagi F , Bianchi P I , Campanella J , Badulli C , Martinetti M , Klersy C , Alvisi C , Luinetti O , Corazza G R 
Published: August 2008

Aims:Although they are non-specific, minimal intestinal lesions are at the end of the coeliac histological damage spectrum. To investigate whether minimal intestinal lesions in patients without endomysial antibodies are due to coeliac disease, their prevalence, causes and risk of evolving into frank coeliac disease were studied.Methods:From January 2000 to December 2005, 645 duodenal biopsies were performed. In 209 patients, duodenal biopsies were performed independently of endomysial antibody results. Clinical data and HLA-typing of all the patients negative to endomysial antibodies but with minimal mucosal lesions were re-evaluated. Three years later, they were offered to be seen again, and further investigations were proposed.Results:14 out of 209 patients had minimal mucosal lesions and negative endomysial antibodies. Two patients were lost to follow-up; in 7/12 patients, symptoms and histological lesions were due to a different condition, not related to coeliac disease. In 11/12 patients, HLA-typing made diagnosis of coeliac disease very unlikely. Only one patient was on a gluten-free diet because of gluten-sensitive symptoms and was DQ2+/DQ8+.Conclusions:Minimal duodenal lesions in patients negative to endomysial antibodies are rare and are likely to be due to conditions unrelated to coeliac disease.
HEAT TREATMENT EFFECTS ON STRUCTURE AND PROPERTIES OF SYNTHESIZED NANOCRYSTALLINE NiTi INTERMETALLIC BY MECHANICAL ALLOYING
Authors: MOUSAVI T. , ABBASI M. H. , KARIMZADEH F. , ENAYATI M. H. 
Published: August 2008

NiTi intermetallic with nanocrystalline structure was produced by mechanical alloying of the elemental powders and the effect of subsequent heat treatment was investigated. The products were characterized using X-ray diffraction and microhardness measurements. The results showed that after 60 h of mechanical alloying, disordered B 2- NiTi phase can be obtained as a metastable phase at room temperature with grain size of 25 nm, lattice strain and high microhardness of 1.2% and 922 HV, respectively. After heat treatment, disordered structure transformed to ordered NiTi and a small amount of NiTi 2 and Ni 3 Ti phases. The long range order parameters of nanocrystalline NiTi were obtained to be 0.63 and 0.94 after annealing for 30 and 60 mins respectively. After 30 mins of heat treatment, 81.5% of Ni (or Ti ) atoms were on the right sites and after 60 mins it increased to 97%. Grain growth and decrease of microhardness and lattice strain were also observed after heat treatment. After 60 mins of heat treatment the grain size, lattice strain and microhardness of NiTi were 95, 0.09 and 624 HV respectively.
Comparison of Ground-Based Radar and Geosynchronous Satellite Climatologies of Warm-Season Precipitation over the United States
Authors: Tuttle John D. , Carbone Richard E. , Arkin Phillip A. 
Published: August 2008

Abstract
Studies in the past several years have documented the climatology of warm-season precipitation-episode statistics (propagation speed, span, and duration) over the United States using a national composited radar dataset. These climatological studies have recently been extended to other continents, including Asia, Africa, and Australia. However, continental regions outside the United States have insufficient radar coverage, and the newer studies have had to rely on geostationary satellite data at infrared (IR) frequencies as a proxy for rainfall. It is well known that the use of IR brightness temperatures to infer rainfall is subject to large errors. In this study, the statistics of warm-season precipitation episodes derived from radar and satellite IR measurements over the United States are compared and biases introduced by the satellite data are evaluated. It is found that the satellite span and duration statistics are highly dependent upon the brightness temperature threshold used but with the appropriate choices of thresholds can be brought into good agreement with those based upon radar data. The propagation-speed statistics of satellite events are on average ∼4 m s−1 faster than radar events and are relatively insensitive to the brightness temperature threshold. A simple correction procedure based upon the difference between the steering winds for the precipitation core and the winds at the level of maximum anvil outflow is developed.
Spatial Coherence and Seasonal Predictability of Monsoon Onset over Indonesia
Authors: Moron Vincent , Robertson Andrew W. , Boer Rizaldi 
Published: August 2008

Abstract
The seasonal potential predictability of monsoon onset during the August–December season over Indonesia is studied through analysis of the spatial coherence of daily station rainfall and gridded pentad precipitation data from 1979 to 2005. The onset date, defined using a local agronomic definition, exhibits a seasonal northwest-to-southeast progression from northern and central Sumatra (late August) to Timor (mid-December). South of the equator, interannual variability of the onset date is shown to consist of a spatially coherent large-scale component, together with local-scale noise. The high spatial coherence of onset is similar to that of the September–December seasonal total, while postonset amounts averaged over 15–90 days and September–December amount residuals from large-scale onset show much less spatial coherence, especially across the main islands of monsoonal Indonesia. The cumulative rainfall anomalies exhibit also their largest amplitudes before or near the onset date. This implies that seasonal potential predictability over monsoonal Indonesia during the first part of the austral summer monsoon season is largely associated with monsoon onset, and that there is much less predictability within the rainy season itself. A cross-validated canonical correlation analysis using July sea surface temperatures over the tropical Pacific and Indian Oceans (20°S–20°N, 80°–280°E) as predictors of local-scale onset dates exhibits promising hindcast skill (anomaly correlation of ∼0.80 for the spatial average of standardized rain gauges and ∼0.70 for standardized gridded pentad precipitation data).