bluuebunny/crossref_metadata_2025_split huggingface dataset:
Prognostic significance of histopathological features of extraprostatic extension of prostate cancer
Authors: Danneman Daniela , Wiklund Fredrik , Wiklund Nils Peter , Egevad Lars 
Published: June 2013

AimsThe 2009 International Society of Urological Pathology consensus conference recommended reporting the extent of extraprostatic extension (EPE) for the prediction of outcome in prostate cancer. Our aim was to stratify EPE into prognostic groups.Methods and resultsWe reviewed 1051 radical prostatectomy (RP) specimens from 1998 to 2005. EPE was classified according to the extent, laterality and presence of perineural invasion (PNI) at the site of EPE. Cox regression was used to explore associations with biochemical recurrence. EPE was observed in 470 cases (44.7%), and predicted a higher progression rate than for organ‐confined cancer [hazard ratio (HR) 1.4, 95% confidence interval (CI) 1.1–1.8, P = 0.007]. Focal versus established EPE according to Epstein (HR 2.0, 95% CI 1.1–3.5, P = 0.027) and Wheeler (HR 2.2, 95% CI 1.2–3.9, P = 0.010), and the radial distance of EPE dichotomized by the median (1.1 mm) (HR 1.5, 95% CI 1.1–2.2, P = 0.015), were all predictive of recurrence; but PNI at the site of EPE, circumferential length of EPE, number of sections and foci with EPE, and bilateral versus unilateral EPE were not.ConclusionsThe radial extent of EPE predicts recurrence after RP, but circumferential extent, PNI at the site of EPE, number of sections or foci of EPE, and laterality do not. If validated, the proposed radial extent method may allow for more reproducible quantitation of EPE.
Expanding the environment: gene × school‐level SES interaction on reading comprehension
Authors: Hart Sara A. , Soden Brooke , Johnson Wendy , Schatschneider Christopher , Taylor Jeanette 
Published: June 2013

BackgroundInfluential work has explored the role of family socioeconomic status (SES) as an environmental moderator of genetic and environmental influences on cognitive outcomes. This work has provided evidence that socioeconomic circumstances differentially impact the heritability of cognitive abilities, generally supporting the bioecological model in that genetic influences are greater at higher levels of family SES. The present work expanded consideration of the environment, using school‐level SES as a moderator of reading comprehension.MethodsThe sample included 577 pairs of twins from the Florida Twin Project on Reading, Behavior and Environment. Reading comprehension was measured by the Florida Comprehensive Achievement Test (FCAT) Reading in third or fourth grade. School‐level SES was measured by the mean Free and Reduced Lunch Status (FRLS) of the schoolmates of the twins.ResultsThe best‐fitting univariate G × E moderation model indicated greater genetic influences on reading comprehension when fewer schoolmates qualified for FRLS (i.e., ‘higher’ school‐level SES). There was also an indication of moderation of the shared environment; there were greater shared environmental influences on reading comprehension at higher school‐level SES.ConclusionsThe results supported the bioecological model; greater genetic variance was found in school environments in which student populations experienced less poverty. In general, ‘higher’ school‐level SES allowed genetic and probably shared environmental variance to contribute as sources of individual differences in reading comprehension outcomes. Poverty suppresses these influences.
A Reference Line on Temporomandibular Joint MRI
Authors: Ikeda Kazumi 
Published: June 2013

AbstractPurposeThe aim of this study was to establish a reference line and the 12 o'clock position on sagittal MRI images of the temporomandibular joint (TMJ) for close observation of early changes in disk position.Materials and MethodsThe study included 106 joints of 53 consecutive male and female patients (mean age 13.3 years) with available MRI and limited cone‐beam computed tomography (LCBCT) images, from a pool of postorthodontic patients who had finished phase I or phase II orthodontic treatment between March 2006 and March 2008 in a private orthodontic office. High‐resolution (0.1 pixel) LCBCT images taken in natural head position in the same time period and adjusted to the same magnification were superimposed on corresponding MRI images. The true horizontal line (THL) determined by natural head position on the LCBCT image was transferred to the MRI image. A clinically easy‐to‐use reference line (RL) approximating THL was drawn by connecting two readily locatable anatomical landmarks, the most inferior point of the articular eminence and the center of the auditory canal, and correspondence between THL and RL was assessed.ResultsThe mean angle formed by THL and RL on the MRI images of the TMJs studied was 2.2° (SD 2.8°) clockwise around the center of the auditory canal, and the angulations of THL and RL on MRI images of the TMJs studied demonstrated a high positive correlation (r = 0.84).ConclusionsTHL can be established directly on MRI images using the THL‐RL angle obtained by this study in patients without advanced disk displacement resulting in bony changes of the joint. The deepest point on the glenoid fossa that meets the THL can be used as the 12 o'clock position for evaluation of incipient disk position change.
Fatigue Behavior of the Resinous Cement to Zirconia Bond
Authors: Seto Kevin B. , McLaren Edward A. , Caputo Angelo A. , White Shane N. 
Published: June 2013

AbstractPurposeResinous cements are widely used for luting zirconia restorations. Adhesive failures have occurred at the cement/zirconia interface, rather than at the cement/dentin interface, suggesting that the cement/zirconia bond may lack durability; however, few comprehensive, comparative evaluations of fatigue effects have been reported. The rate of fatigue‐induced loss of bond strength may be a more important predictor of long‐term success than a single snapshot of bond strength after an arbitrary number of thermocycles. Previous studies have failed to identify trends by investigating bond strengths at several different numbers of cycles. This may result in invalid conclusions about which cements have superior bond strengths. The purpose of this study was to investigate the effects of artificial aging by thermocycling and resinous cement type on bond strengths to zirconia.Materials and MethodsThe effect of the number of thermocycles (0, 1, 10, 100, 1000, and 10,000) on the bond strengths of five resinous cements, two of which were used with and without a primer, and an oxygen‐inhibiting gel, was studied. Specimens were randomly assigned to thermocycle number/cement‐type test groups. Because zirconia has a very low thermal diffusivity, exceptionally long thermocycle dwell times were used. Cylinders of zirconia were bonded end‐to‐end. One end of each bonded specimen was insulated, specimens were thermocycled and tested in shear, and bond strengths were calculated and analyzed.ResultsTwo‐way ANOVA revealed that the effects of cement type, the number of thermocycles, and their interaction all significantly affected bond strength (p < 0.0001). By 10,000 cycles, most cements had lost at least half of their initial bond strengths, and two cements effectively recorded zero bond strengths. Failure modes were cement specific, but adhesive modes predominated. Fatigue resistance of two cements was greatly improved by use of a primer and an oxygen‐inhibiting gel, as recommended by their respective manufacturers.ConclusionsBoth the type of resin cement and the number of thermocycles influenced bond strength. Fatigue through thermocycling affected different cement types in different ways. Some materials displayed more rapid loss of bond strength than others. Cements differed in their failure modes.
Surface Characteristics and Cell Adhesion: A Comparative Study of Four Commercial Dental Implants
Authors: Liu Ruohong , Lei Tianhua , Dusevich Vladimir , Yao Xiamei , Liu Ying , Walker Mary P. , Wang Yong , Ye Ling 
Published: June 2013

AbstractPurposeThe aims of this study were to compare surface properties of four commercial dental implants and to compare those implant systems’ cell adhesion, which may be affected by the surface properties, and to provide scientific information on the selection of implants for clinicians.Materials and MethodsThe surface properties of four commonly used dental implants (3i Nanotite™, Astra OsseoSpeed™, Nobel Biocare TiUnite®, and Straumann SLActive®) were studied using MicroSpy profiler, scanning electron microscopy (SEM), energy dispersive X‐ray spectroscopy, and Raman microspectroscopy. Primary mouse alveolar bone cells were cultured on the surface of implants from the four companies. After 48‐hour culture, SEM in combination with a quantitative analysis of SEM images was used to examine the cell adhesion. Cell adhesion rates (ratios of cell surface to implant surface) among different systems were compared.ResultsDistinct differences were found among these implants. Comparisons of roughness among three locations: flank, top, and valley within the same implant system, or in the same location among different implants were made. Generally Astra and Straumann systems showed the roughest surface, whereas 3i showed the smoothest surface. Multiple cracks were found on the surface of the Nobel Biocare system, which also had a dramatically lower level of titanium. In addition, rutile phase of titanium oxide was found in 3i, Astra, and Straumann systems, and anatase phase of titanium oxide was only detected in the Nobel Biocare system. After 48‐hour culture, Astra and Straumann systems displayed the highest cell adhesion at the areas of flank, top, and valley of the implant surface. Primary cells also reached confluence on the valley, but significantly less in the 3i system. Nobel Biocare showed the least cell adhesion on the flank and valley.ConclusionImplant systems have distinct differences in surface properties, leading to different cell adhesion results. Further in vivo study is needed to study the impact of the surface characteristics and different cell adhesion on the osseointegration between implant and bone.
Bond Strength of the Porcelain Repair System to All‐Ceramic Copings and Porcelain
Authors: Lee Sang J. , Cheong Chan Wook , Wright Robert F. , Chang Brian M. 
Published: June 2013

AbstractPurposeThe purpose of this study was to investigate the shear bond strength of the porcelain repair system on alumina and zirconia core ceramics, comparing this strength with that of veneering porcelain.Materials and MethodsVeneering ceramic (n = 12), alumina core (n = 24), and zirconia core (n = 24) blocks measuring 10 × 5 × 5 mm3 were fabricated. Veneering ceramic blocks were used as the control. Alumina and zirconia core blocks were divided into 2 groups (n = 12 each), and a slot (2 × 2 × 4 mm3) filled with veneering ceramics was prepared into one of the alumina and zirconia core groups (n = 12). Followed by surface treatments of micro‐abrasion with 30 μm alumina particles, etching with 35% phosphoric acid and silane primer and bond, composite resin blocks (2 × 2 × 2 mm3) were built up and light polymerized onto the treated surfaces by 3 configurations: (a) composite blocks bonded onto veneering ceramic surface alone, (b) composite blocks bonded onto alumina core or zirconia core surfaces, (c) a 50% surface area of the composite blocks bonded to veneering ceramics and the other 50% surface area of the composite blocks to alumina core or zirconia core surfaces. The shear bond strength of the composite to each specimen was tested by a universal testing machine at a 0.5 mm/min crosshead speed. The shear bond strength was analyzed by unpaired t‐tests for within the configuration groups and ANOVA for among the different configuration groups.ResultsWhen the mean shear bond strength was compared within groups of the same configuration, there were no statistically significant differences. Comparison of the shear bond strength among groups of different configurations revealed statistically significant differences. The mean shear bond strength of composite onto 100% veneering ceramic surface and composite onto 50% veneering 50% all‐ceramic cores was statistically higher than that of composite onto 100% all‐ceramic cores; however, the differences of the shear bond strength of composite bonded only onto the veneering ceramic surface were not statistically significant from those of 50% surface area of composite bonded onto all‐ceramic cores.ConclusionNo statistically significant differences in the bond strength of a porcelain repair system to alumina and zirconia copings were observed. Increasing the surface of veneering ceramics to a porcelain repair system improved the repair material's bond strength.
Influence of Abutment Type and Esthetic Veneering on Preload Maintenance of Abutment Screw of Implant‐Supported Crowns
Authors: Delben Juliana Aparecida , Barão Valentim Adelino Ricardo , Dos Santos Paulo Henrique , Assunção Wirley Gonçalves 
Published: June 2013

AbstractPurposeThe effect of veneering materials on screw joint stability remains inconclusive. Thus, this study evaluated the preload maintenance of abutment screws of single crowns fabricated with different abutments and veneering materials.Materials and MethodsSixty crowns were divided into five groups (n = 12): UCLA abutment in gold alloy with ceramic (group GC) and resin (group GR) veneering, UCLA abutment in titanium with ceramic (group TiC) and resin (group TiR) veneering, and zirconia abutment with ceramic veneering (group ZiC). Abutment screws made of gold were used with a 35 Ncm insertion torque. Detorque measurements were obtained initially and after mechanical cycling. Data were analyzed by ANOVA and Fisher's exact test at a significance level of 5%.ResultsFor the initial detorque means (in Ncm), group TiC (21.4 ± 1.78) exhibited statistically lower torque maintenance than groups GC (23.9 ± 0.91), GR (24.1 ± 1.34), and TiR (23.2 ± 1.33) (p < 0.05, Fisher's exact test). Group ZiC (21.9 ± 2.68) exhibited significantly lower torque maintenance than groups GC, GR, and TiR (p < 0.05, Fisher's exact test). After mechanical cycling, there was a statistically significant difference between groups TiC (22.1 ± 1.86) and GR (23.8 ± 1.56); between groups ZiC (21.7 ± 2.02) and GR; and also between groups ZiC and TiR (23.6 ± 1.30) (p < 0.05, Fisher's exact test).ConclusionsDetorque reduction occurred regardless of abutment type and veneering material. More irregular surfaces in the hexagon area of the castable abutments were observed. The superiority of any veneering material concerning preload maintenance was not established.
Maxillary Rehabilitation Using Fixed and Removable Partial Dentures with Attachments: A Clinical Report
Authors: dos Santos Nunes Reis José Maurício , da Cruz Perez Luciano Elias , Alfenas Bruna Fernandes Moreira , de Oliveira Abi‐Rached Filipe , Filho João Neudenir Arioli 
Published: June 2013

AbstractDespite requiring dental crown preparation and possible root canal treatment, besides the difficulty of clinical and laboratory repairs, and financial burden, the association between fixed (FPD) and removable partial dentures (RPD) by means of attachments is an important alternative for oral rehabilitation, particularly when the use of dental implants and FPDs is limited or not indicated. Among the advantages of attachment‐retained RPDs are the improvements in esthetics and biomechanics, as well as correction of the buccal arrangement of anterior teeth in Kennedy Class III partially edentulous arches. This article describes the treatment sequence and technique for the use of attachments in therapy combining FPD/RPD.
Longitudinal Associations between Violence and Suicidality from Adolescence into Adulthood
Authors: Van Dulmen Manfred , Mata Andrea , Claxton Shannon , Klipfel Katherine , Schinka Katherine , Swahn Monica , Bossarte Robert 
Published: June 2013

The link between violence and suicide is well documented. Previous studies, however, largely rely on cross‐sectional designs or only consider violence as an antecedent of suicide. The purpose of the current study was to investigate the longitudinal relationship between violence and suicide from adolescence into young adulthood. Data were derived from Wave II (1995–1996), Wave III (2001–2002), and Wave IV (2007–2008) of the National Longitudinal Study of Adolescent Health (N = 8,966). We tested (2011–2013) a series of path analysis models in Mplus to determine the longitudinal associations between violence and suicidality. Results from the path analyses indicated that violence and suicidality mutually affect each other from adolescence into young adulthood. We found some evidence that the association between suicidality and violence was stronger for males compared to females, particularly in early and young adulthood. The current study confirms previous findings by demonstrating that violence is a risk factor for future suicide. We also extended the previous literature by demonstrating that a history of suicidality is associated with future risk for violence. Our findings highlight the importance of further integrating prevention efforts to reduce violence and suicidality during adolescence and early/young adulthood.
Using a periclinal chimera to unravel layer‐specific gene expression in plants
Authors: Filippis Ioannis , Lopez‐Cobollo Rosa , Abbott James , Butcher Sarah , Bishop Gerard J. 
Published: June 2013

SummaryPlant organs are made from multiple cell types, and defining the expression level of a gene in any one cell or group of cells from a complex mixture is difficult. Dicotyledonous plants normally have three distinct layers of cells, L1, L2 and L3. Layer L1 is the single layer of cells making up the epidermis, layer L2 the single cell sub‐epidermal layer and layer L3 constitutes the rest of the internal cells. Here we show how it is possible to harvest an organ and characterise the level of layer‐specific expression by using a periclinal chimera that has its L1 layer from Solanum pennellii and its L2 and L3 layers from Solanum lycopersicum. This is possible by measuring the level of the frequency of species‐specific transcripts. RNA‐seq analysis enabled the genome‐wide assessment of whether a gene is expressed in the L1 or L2/L3 layers. From 13 277 genes that are expressed in both the chimera and the parental lines and with at least one polymorphism between the parental alleles, we identified 382 genes that are preferentially expressed in L1 in contrast to 1159 genes in L2/L3. Gene ontology analysis shows that many genes preferentially expressed in L1 are involved in cutin and wax biosynthesis, whereas numerous genes that are preferentially expressed in L2/L3 tissue are associated with chloroplastic processes. These data indicate the use of such chimeras and provide detailed information on the level of layer‐specific expression of genes.
On the use of biomathematical models in patient‐specific IMRT dose QA
Authors: Zhen Heming , Nelms Benjamin E. , Tomé Wolfgang A. 
Published: June 2013

Purpose:To investigate the use of biomathematical models such as tumor control probability (TCP) and normal tissue complication probability (NTCP) as new quality assurance (QA) metrics.Methods:Five different types of error (MLC transmission, MLC penumbra, MLC tongue and groove, machine output, and MLC position) were intentionally induced to 40 clinical intensity modulated radiation therapy (IMRT) patient plans (20 H&N cases and 20 prostate cases) to simulate both treatment planning system errors and machine delivery errors in the IMRT QA process. The changes in TCP and NTCP for eight different anatomic structures (H&N: CTV, GTV, both parotids, spinal cord, larynx; prostate: CTV, rectal wall) were calculated as the new QA metrics to quantify the clinical impact on patients. The correlation between the change in TCP/NTCP and the change in selected DVH values was also evaluated. The relation between TCP/NTCP change and the characteristics of the TCP/NTCP curves is discussed.Results:ΔTCP and ΔNTCP were summarized for each type of induced error and each structure. The changes/degradations in TCP and NTCP caused by the errors vary widely depending on dose patterns unique to each plan, and are good indicators of each plan's “robustness” to that type of error.Conclusions:In thisin silico QA study the authors have demonstrated the possibility of using biomathematical models not only as patient‐specific QA metrics but also as objective indicators that quantify, pretreatment, a plan's robustness with respect to possible error types.
Bacterial Tethering Analysis Reveals a “Run-Reverse-Turn” Mechanism for Pseudomonas Species Motility
Authors: Qian Chen , Wong Chui Ching , Swarup Sanjay , Chiam Keng-Hwee 
Published: June 2013

ABSTRACT

We have developed a program that can accurately analyze the dynamic properties of tethered bacterial cells. The program works especially well with cells that tend to give rise to unstable rotations, such as polar-flagellated bacteria. The program has two novel components. The first dynamically adjusts the center of the cell's rotational trajectories. The second applies piecewise linear approximation to the accumulated rotation curve to reduce noise and separate the motion of bacteria into phases. Thus, it can separate counterclockwise (CCW) and clockwise (CW) rotations distinctly and measure rotational speed accurately. Using this program, we analyzed the properties of tethered
Pseudomonas aeruginosa
and
Pseudomonas putida
cells for the first time. We found that the
Pseudomonas
flagellar motor spends equal time in both CCW and CW phases and that it rotates with the same speed in both phases. In addition, we discovered that the cell body can remain stationary for short periods of time, leading to the existence of a third phase of the flagellar motor which we call “pause.” In addition,
P. aeruginosa
cells adopt longer run lengths, fewer pause frequencies, and shorter pause durations as part of their chemotactic response. We propose that one purpose of the pause phase is to allow the cells to turn at a large angle, where we show that pause durations in free-swimming cells positively correlate with turn angle sizes. Taken together, our results suggest a new “run-reverse-turn” paradigm for polar-flagellated
Pseudomonas
motility that is different from the “run-and-tumble” paradigm established for peritrichous
Escherichia coli
.
Engineering the
meso
-Diaminopimelate Dehydrogenase from Symbiobacterium thermophilum by Site Saturation Mutagenesis for
d
-Phenylalanine Synthesis
Authors: Gao Xiuzhen , Huang Fang , Feng Jinhui , Chen Xi , Zhang Hailing , Wang Zhixiang , Wu Qiaqing , Zhu Dunming 
Published: June 2013

ABSTRACT

In order to enlarge the substrate binding pocket of the
meso
-diaminopimelate dehydrogenase from
Symbiobacterium thermophilum
to accommodate larger 2-keto acids, four amino acid residues (Phe146, Thr171, Arg181, and His227) were targeted for site saturation mutagenesis. Among all mutants, the single mutant H227V had a specific activity of 2.39 ± 0.06 U · mg
−1
, which was 35.1-fold enhancement over the wild-type enzyme.
Improved Bacterial Mutagenesis by High-Frequency Allele Exchange, Demonstrated in Clostridium difficile and Streptococcus suis
Authors: Faulds-Pain Alexandra , Wren Brendan W. 
Published: June 2013

ABSTRACT

Here we show that the frequency of mutant isolation by two-step allele exchange can be improved by increasing the length of homologous DNA and the opportunity for recombination, obviating the need for counterselection markers. These principles are demonstrated in
Clostridium difficile
and
Streptococcus suis
but are likely to be generally applicable.