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General dental practice is increasingly being recognised as the ideal situation for the conduct of clinical trials into the longevity of restorations. The aim of this study was to investigate the survival of 64 nanofilled resin composite (Filtek Supreme XTE) restorations placed principally in loadbearing cavities using a Universal dentine bonding agent (Scotchbond Universal), in five UK dental practices by members of the UK-based practice-based research group, the PREP Panel. A split mouth design was used, comprising patients who required two restorations, with one of the restorations receiving a total etch approach using phosphoric acid and the other being placed using a self-etch approach. The results indicated good performance of the restorations examined, with no difference, in terms of marginal characteristics, between the restorations which received total etching and those which did not.

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General dental practice is increasingly being recognised as the ideal situation for the conduct of clinical trials into the longevity of restorations. The aim of this study was to investigate the survival of 75 nanofilled resin composite restorations placed in an assortment of cavities using a self-etch dentine bonding agent, in five UK dental practices by members of the UK-based practice-based research group, the PREP Panel, with half of the restorations receiving a selective enamel etch and the other half being placed using a self-etching approach. The results indicated good performance of the restorations examined, with no failures being identified and excellent surface characteristics, in terms of colour stability, minimal surface roughness and optimal anatomic form. Selective enamel etching tended to produce less marginal discolouration, although these results were not statistically significant.

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BACKGROUND AND PURPOSE: Carotid webs are intraluminal shelf-like filling defects at the carotid bulb with recently recognized implications in patients with recurrent ischemic stroke. We sought to determine whether carotid webs are an under-recognized cause of "cryptogenic" ischemic stroke and to estimate their prevalence in the general population. MATERIALS AND METHODS: A retrospective review of neck CTA studies in young patients with cryptogenic stroke over the past 6 years (n = 33) was performed to determine the prevalence of carotid webs compared with a control group of patients who received neck CTA studies for reasons other than ischemic stroke (n = 63). RESULTS: The prevalence of carotid webs in the cryptogenic stroke population was 21.2% (95% CI, 8.9%-38.9%). Patients with symptomatic carotid webs had a mean age of 38.9 years (range, 30-48 years) and were mostly African American (86%) and women (86%). In contrast, only 1.6% (95% CI, 0%-8.5%) of patients in the control group demonstrated a web. Our findings demonstrate a statistically significant association between carotid webs and ischemic stroke (OR = 16.7; 95% CI, 2.78-320.3; P = .01). CONCLUSIONS: Carotid webs exhibit a strong association with ischemic stroke, and their presence should be suspected in patients lacking other risk factors, particularly African American women.

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Analysis of a radioactive, coated concrete core from the decommissioned, spent nuclear fuel cooling pond at the Hunterston-A nuclear site (UK) has provided a unique opportunity to study radionuclides within a real-world system. The core, obtained from a dividing wall and sampled at the fill level of the pond, exhibited radioactivity (dominantly (137)Cs and (90)Sr) heterogeneously distributed across both painted faces. Chemical analysis of the core was undertaken using microfocus spectroscopy at Diamond Light Source, UK. Mapping of Sr across the surface coatings using microfocus X-ray fluorescence (µXRF) combined with X-ray absorption spectroscopy showed that Sr was bound to TiO2 particles in the paint layers, suggesting an association between TiO2 and radiostrontium. Stable Sr and Cs sorption experiments using concrete coupons were also undertaken to assess their interactions with the bulk concrete in case of a breach in the coating layers. µXRF and scanning electron microscopy showed that Sr was immobilized by the cement phases, whilst at the elevated experimental concentrations, Cs was associated with clay minerals in the aggregates. This study provides a crucial insight into poorly understood infrastructural contamination in complex systems and is directly applicable to the UK's nuclear decommissioning efforts.

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OBJECTIVE: To examine whether differences exist in routine first trimester maternal serum screening analyte measurements between normal pregnancies, placenta praevia and abnormally invasive placentation (AIP). DESIGN: Multidisciplinary audit. SETTING: Associated university teaching hospital with 9000 annual deliveries. POPULATION: Five hundred and sixteen pregnancies in total, including 344 normal controls, 17 with AIP and 155 placenta praevia cases. METHODS: Comparison of maternal serum free ßhCG and PAPP-A MoMs distribution in pregnancies with abnormally invasive placentation, placenta praevia and normal controls, after correcting for known confounding factors between October 2005 and September 2013. Data from a previously published first trimester AIP and biochemistry study were combined with our study data and compared in the above way to complete the analysis. MAIN OUTCOME MEASURES: Differences in first trimester maternal serum PAPP-A and free ßhCG in AIP, placenta praevia, and normal pregnancies. RESULTS: Median free ßhCG MoM in the control group was 1.04, and 1.08 (P = 0.859) in the placenta praevia group compared with 0.81 in the AIP group (P = 0.06). Median PAPP-A MoM was 1.01 in the control group and 1.05 (P = 0.83) in praevia, compared with 1.22 in AIP cases (0.16). The combined AIP dataset gave an overall PAPP-A median MoM of 1.40, and free ßhCG of 0.85. Both markers showed a significantly different distribution from controls (PAPP-A P = 0.002 and free ßhCG P = 0.031). CONCLUSIONS: There may be differences between first trimester maternal serum biochemical markers between normal pregnancies and those complicated by abnormally invasive placentation. If upheld, this may provide useful information for the early identification of abnormally invasive placentation. More studies are required.

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OBJECTIVES: This study reported the results at 5 years of fixed-fixed all-ceramic bridges, constructed in a yttria oxide stabilized tetragonal zirconium oxide polycrystal (Y-TZP) substructure, placed in adult patients in UK general dental practices. MATERIALS AND METHODS: Four UK general dental practitioners recruited patients who required fixed bridgework and, after obtaining informed written consent, appropriate clinical and radiographic assessments were completed. The teeth were prepared and bridges constructed in accordance with the manufacturer's instructions. Each bridge was reviewed annually within 3 months of the anniversary of its placement by a calibrated examiner, together with the clinician who had placed the restoration, using modified USPHS criteria. RESULTS: Of the 41 bridges originally placed, 33 bridges were examined at 5 years. All Y-TZP frameworks were intact and no bridge retainers had debonded. Eight chipping fractures in the veneering ceramic were noted over the 5-year period. In five cases the patients were unaware of these and these cases were polished. Of the remaining three cases, in one a repair was attempted but was unsuccessful, but the bridge remained in satisfactory service. However, in the case involving a chipping fracture of the mesial-incisal angle of a central incisor, it was considered that replacement of the bridge was necessary. CONCLUSION: 97% (n=32) of the 33 Lava Y-TZP fixed-fixed bridges, evaluated in patients attending UK general dental practices, were found to be performing satisfactorily. CLINICAL RELEVANCE: The use of Y-TZP frameworks holds promise.

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OBJECTIVES: To report the results at year three of an evaluation of fixed-fixed all-ceramic bridges, constructed in a yttria oxide stabilized tetragonal zirconium oxide polycrystal (Y-TZP) substructure, placed in adult patients in UK general dental practices and luted using a self-adhesive resin-based cement. METHODS: Ethical approval was obtained. Four UK general dental practitioners were asked to recruit patients in accordance with the trial protocol. After obtaining informed written consent, appropriate vitality and radiographic assessments were completed and the pre-operative status of the gingival tissues noted. The teeth were prepared and bridges constructed in accordance with the manufacturer's instructions. Each bridge was reviewed annually within 3 months of the anniversary of its placement by a calibrated examiner, together with the clinician who had placed the restoration. The examiners evaluated the integrity of the restoration, its anatomic form, marginal adaptation, surface quality, sensitivity, the condition of the adjacent gingivae, and the presence or absence of secondary caries. RESULTS: A total of 34 bridges were examined at the three-year review. All Y-TZP frameworks were intact and no bridge retainers had debonded. Two veneering ceramic chips, in total, were detected over the three-year period of observation: the patients in whom this had occurred were unconcerned. A further abutment tooth had been successfully endodontically treated, through an occlusal access cavity, in addition to the two already reported at year one. SIGNIFICANCE: At year three, the 34 Lava Y-TZP fixed-fixed bridges, placed in patients attending UK general dental practices, were found to be performing satisfactorily.

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OBJECTIVE: A novel resin composite system, Filtek Silorane (3M ESPE) with reduced polymerization shrinkage has recently been introduced. The resin contains an oxygen-containing ring molecule ('oxirane') and cures via a cationic ring-opening reaction rather than a linear chain reaction associated with conventional methacrylates and results in a volumetric shrinkage of ∼1%. The purpose of this study was to review the literature on a recently introduced resin composite material, Filtek Silorane, and evaluate the clinical outcome of restorations formed in this material. METHODS: Filtek Silorane restorations were placed where indicated in loadbearing situations in the posterior teeth of patients attending five UK dental practices. These were evaluated, after two years, using modified USPHS criteria. RESULTS: A total of 100 restorations, of mean age 25.7 months, in 64 patients, were examined, comprised of 30 Class I and 70 Class II. All restorations were found to be present and intact, there was no secondary caries. Ninety-seven per cent of the restorations were rated optimal for anatomic form, 84% were rated optimal for marginal integrity, 77% were rated optimal for marginal discoloration, 99% were rated optimal for color match, and 93%% of the restorations were rated optimal for surface quality. No restoration was awarded a "fail" grade. No staining of the restoration surfaces was recorded and no patients complained of post-operative sensitivity. SIGNIFICANCE: It is concluded that, within the limitations of the study, the two year assessment of 100 restorations placed in Filtek Silorane has indicated satisfactory clinical performance.

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PURPOSE: To report the results at year one of a three-year evaluation of the performance of fixed all-ceramic bridges, constructed with a yttrium tetragonal zirconia polycrystal substructure placed in adult patients in UK general dental practices and cemented using a self-adhesive resin-based cement. METHODS: Ethical approval was obtained. Four UK general dental practitioners were asked to recruit patients complying with the trial criteria and protocol. After obtaining informed written consent, appropriate vitality and radiographic assessments were completed and the pre-operative status of the gingival tissues noted. The teeth were prepared and bridges constructed using the same technician and laboratory procedures. Each bridge was reviewed within three months of the anniversary of its placement by a calibrated examiner together with the clinician who had placed the restoration. The examiners evaluated the integrity of the restoration, its anatomic form, marginal adaptation, surface quality, sensitivity, the condition of the adjacent gingivae, and the presence or absence of secondary caries. RESULTS: All the bridges (n = 38) examined at the first-year review were present, intact and performing well, though one small chip of the veneering porcelain was detected and in two cases an abutment tooth had been endodontically treated through an occlusal access cavity.

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Dystroglycan is a cell adhesion molecule that interacts with ezrin family proteins and also components of the extracellular signal-regulated kinase pathway. Ezrin and extracellular signal-regulated kinase are both involved in aspects of the cell division cycle. We therefore examined the role of dystroglycan during cytokinesis. Endogenous dystroglycan colocalised with ezrin at the cleavage furrow and midbody during cytokinesis in REF52 cells. Live cell imaging of green fluorescent protein-tagged dystroglycan in Swiss 3T3 and Hela cells revealed a similar localisation. Live cell imaging of a dystroglycan lacking its cytoplasmic domain revealed an even membrane localisation but no cleavage furrow or midbody localisation. Deletion of a previously identified ezrin-binding site in the dystroglycan cytoplasmic domain however only resulted in a slight reduction in cleavage furrow localisation but loss of midbody staining. There was no apparent cytokinetic defect in cells depleted for dystroglycan, however apoptosis levels were considerably higher in dystroglycan knockdown cells. Cell cycle analysis showed a delay in G2/M transition, possibly caused by a more than 50% reduction in extracellular signal-regulated kinase levels in the knockdown cells. Dystroglycan may therefore not only have a role in organising the contractile ring through direct or indirect associations with actin, but can also modulate the cell cycle by affecting extracellular signal-regulated kinase levels.

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OBJECTIVES: To describe child and adolescent dietary patterns and to determine associations between childhood dietary pattern and longitudinal change in body mass index (BMI) z-score among girls. POPULATION AND METHODS: Healthy girls (n = 101) aged 8-12 years at baseline and 11-19 years at follow-up participated in a longitudinal study of growth and development. Participants kept 7-day dietary records at two points in time. We incorporated time of day, frequency, and amount of energy consumed (defined as percentage of total energy consumed per dietary event) when characterizing dietary patterns. RESULTS: Girls ate an average of 4-5 times per day and consumed most energy in the afternoon and in the evening/night, rather than in the morning. After controlling for baseline BMI, the mean percentage of daily energy consumed in the evening/night was positively associated with change in BMI z-score (P = 0.039). Eating between 4.0 and 5.9 times per day overall and no more than 1.9 times in the evening/night daily were negatively associated with change in BMI z-score (P = 0.002 and 0.047, respectively), after controlling for baseline BMI z-score. DISCUSSION: Recommendations to decrease the percentage of energy coming from the evening/night meal and the number of dietary events to no more than six times per day and two times in the evening/night should be evaluated in future longitudinal investigations.

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OBJECTIVE: To evaluate blood-volume flow-rate measurement in the fetal descending thoracic aorta using a non-invasive, non-Doppler, ultrasound technique. METHODS: This was a cross-sectional, observational study. Volume flow measurements were obtained from the descending thoracic aorta in 59 human fetuses between 20 and 40 weeks' gestation. These were uncomplicated pregnancies that resulted in the live births of appropriately grown infants. The measurements were obtained using a time domain processing technique: color velocity imaging quantification (CVI-Q). RESULTS: The blood-volume flow rate increased consistently from the second trimester until term. The mean values ranged between 100 mL/min at 20 weeks' gestation and approximately 350 mL/min at term. The normalized (weight-adjusted) volume flow rates decreased with increasing gestation, from a maximum of 626 mL/min/kg at 23 weeks to a minimum of 45.6 mL/min/kg at 37 weeks. CONCLUSIONS: The regular measurement of blood-volume flow in the descending fetal thoracic aorta is feasible using CVI-Q. Although there is a considerable learning curve, with adequate training there are potential clinical applications for this non-Doppler technique. However, limitations exist with the currently available technology for clinical use in fetal vascular studies.

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OBJECTIVES: To assess the relationship between eating food purchased away from home (FAH) and longitudinal change in body mass index (BMI) z-score among girls, and to assess the longitudinal tracking of eating FAH from childhood through adolescence. DESIGN: Participants kept 7-day dietary records at two points in time. The records included the place and time for all foods consumed. We recorded how often participants ate FAH, calculated the percent of total energy derived from FAH, and classified foods as quick-service food, coffee-shop food, or restaurant food. PARTICIPANTS: Healthy girls (n=101) between the ages of 8 and 12 y at baseline and 11 and 19 y at follow-up participated in a longitudinal study of growth and development at the Massachusetts Institute of Technology. STATISTICAL ANALYSES: Analysis of variance was used to assess the relationship between change in BMI z-score and both the frequency of eating FAH and energy derived from eating FAH. The participants' baseline BMI z-score was a significant covariate and was controlled for in both models. We used the kappa coefficient to assess FAH tracking from childhood through adolescence. RESULTS: The frequency of eating quick-service food at baseline was positively associated with change in BMI z-score (F=6.49, P<0.01). Participants who ate quick-service food twice a week or more at baseline had the greatest mean increase in BMI z-score compared to those who ate quick-service food once a week or not at all. Quick-service food eating tracked slightly from childhood through adolescence (k=0.17, P<0.05). DISCUSSION: Adolescent girls who eat quick-service food twice a week or more are likely to increase their relative BMI over time.

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OBJECTIVE: To evaluate the screening efficacy of second-trimester maternal serum inhibin-A combined with uterine artery Doppler studies performed at 20 weeks' gestation for the prediction of pre-eclampsia. METHODS: Six hundred and eighty-nine consecutive unselected women who had inhibin-A levels measured between 15 and 19 weeks' gestation subsequently had color flow pulsed Doppler of both uterine arteries at the time of the anomaly scan (mean 20.5, range 18-22 weeks' gestation). The main outcome measures were pre-eclampsia and pre-eclampsia requiring delivery before 37 weeks' gestation. The presence or absence of notches in the flow velocity waveform was noted, and the resistance index measured. Receiver operator curves were created for inhibin-A and uterine artery Dopplers alone and in combination. Sensitivities for each method were compared at false-positive rates of 3% and 7%. RESULTS: Thirty-five women developed pre-eclampsia, of whom 15 required delivery before 37 weeks' gestation. For a false-positive rate of 7%, the sensitivity using bilateral notches/mean resistance index > or = 0.65 was 60% with a positive likelihood ratio of 8.6 (confidence interval 5.7-12.6). For the same false-positive rate, when bilateral notches/mean resistance index > or = 0.55 and unilateral notches/mean resistance index > or = 0.65 were combined with inhibin-A > or = 1.0 multiples of the median, the sensitivity improved to 71% and the positive likelihood ratio to 10.8 (confidence interval 7.4-15.4). For pre-eclampsia requiring delivery before 37 weeks for a false-positive rate of 3%, the sensitivity for bilateral notches improved from 27% to 60% and the positive likelihood ratio improved from 9.2 to 20.8 when uterine artery notch data was combined with inhibin-A. The improvement in sensitivity for the combined method, compared to either inhibin-A or uterine artery Dopplers alone, was statistically significant for both pre-eclampsia ( P < 0.05) and preterm pre-eclampsia ( P < 0.02). CONCLUSION: Combination of second-trimester serum inhibin-A and uterine artery Doppler at 20 weeks improves the screening efficacy for the prediction of pre-eclampsia especially when this necessitates early delivery. This combination might form the basis of an effective and practical early screening test for the condition.

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OBJECTIVES: To evaluate the performance of velocimetric indices of uterine artery flow velocity waveforms (FVW's) at 20 weeks' gestation, alone or in combination with qualitative analysis, and establish the optimal screening method for the prediction of pre-eclampsia. METHODS: A total of 614 primiparous women had color flow/pulsed Doppler (CFPD) imaging of both uterine arteries at 20 weeks gestation. Receiver operator characteristic (ROC) curves were created for the systolic/end-diastolic (A/B) ratio, resistance index (RI) and systolic/early diastolic (A/C) ratio for placental and non-placental uterine arteries, individually or in combination with the presence of unilateral or bilateral notches. Based on data from ROC curves, the sensitivity of each method was compared with the false-positive rate set at 17 and 11%. RESULTS: The highest sensitivity (88%) and specificity of (83%) was obtained using bilateral notches/mean RI > or = 0.55 (50th centile) and unilateral notches/mean RI > or = 0.65 (80th centile). When the false-positive rate was set at 17%, the inclusion of bilateral notches significantly improved the sensitivity of RI (P < 0.001), placental RI (P < 0.01), placental A/C ratio (P < 0.05), mean A/C ratio (P < 0.01) and mean A/B ratio (P < 0.05). Bilateral notches/mean RI or A/B cut-offs were also superior to the persistence of a notch in either artery combined with RI (P < 0.01) or A/B ratio (P < 0.05). When the false-positive rate was set at 11%, the inclusion of bilateral notches did not improve the sensitivity of the A/C (P = 1.00) or A/B ratio (P > 0.10). Placental velocimetric indices performed better than mean indices but the differences in sensitivity at the set false-positive rates were not statistically significant. CONCLUSION: At 20 weeks' gestation, bilateral notches with mean RI cut-offs is the best screening method if further screening later in pregnancy is proposed. The A/C ratio is complementary to bilateral notches when the false-positive rate is set at 17% and an effective quantitative substitute when the false-positive rate is set at 11%.

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OBJECTIVE: Maternal serum inhibin A concentration is elevated in established preeclampsia. The aim of this study was to investigate whether this relationship antedates the appearance of the classic signs of preeclampsia. STUDY DESIGN: A retrospective analysis was performed on trisomy 21 screening data from 685 women at between 15 and 19 weeks' gestation. The main outcome measures were preeclampsia and small for gestational age (<5th percentile) infants. RESULTS: Preeclampsia developed in 35 women (5.5%). Women with inhibin A concentration >2.0 multiples of the median were significantly more likely to acquire preeclampsia (P <.00001) and to be delivered of a small for gestational age infant (<5th percentile, P <.00001) than were women with inhibin A concentration

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A complaint of decreased fetal movements is a common indication for the assessment of fetal well being. The aim of this study was to review the outcome of a group of women whose primary indication for referral was decreased fetal movements. Over a 20 month period, 435 patients were seen in the fetal assessment unit of an inner London teaching hospital, following a primary complaint of reduced fetal movements. Investigations included: the fetal abdominal circumference (AC), amniotic fluid volume (AFV), the umbilical artery pulsatility index (UAPI) derived from Doppler ultrasound waveforms and a computerised analysis of fetal heart rate (FHR) recordings or cardiotocograph (CTG). Outcome measures were: gestational age at delivery, Apgar score < 7 at 5 minutes, admission to the Special Care Baby Unit (SCBU), the need for delivery by an emergency cesarean section for fetal compromise (CSFC), and any perinatal deaths. A comparison of actual versus expected outcome for women with decreased fetal movement revealed the following relative risks, with the 95% confidence intervals (CI) in brackets; low 5 minute Apgar score 0.03 vs. 0.05 expected (CI = 0.01, 0.05), SCBU admission, 0.06 vs. 0.07 (0.04, 0.08), and preterm delivery, 0.08 vs. 0.11 (0.05, 0.10). Cesarean sections for fetal compromise, 0.07 vs. 0.053 (0.050-0.096). The addition of FHR monitoring to standard ultrasound assessment of well being did not appear to confer any added benefit. There were no fetal deaths. The outcome for pregnancies where the mother presents with decreased fetal movements in the third trimester is comparable with the outcome for the general population.

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AIMS: To determine the prevalence of polyhydramnios in a routine antenatal population, in which first and second trimester ultrasound screening for fetal abnormality had been performed and to examine the outcome in these pregnancies. METHODS: A retrospective analytical survey of all obstetric ultrasound examinations performed in a university teaching hospital over a thirty-six month period. Polyhydramnios was defined as either the measurement of a single deepest pool of liquor > 8 cm (AFV) or according to the amniotic fluid index, the sum of a four quadrant measurement > 24 cm (AFI). Using the stated definitions, polyhydramnios was diagnosed in 37 women, 16 of whom had a raised AFI. The main outcomes of interest included the mode of onset of labour and mode of delivery (rates of spontaneous and induced labour, cesarean section deliveries), birth weight, presence or absence of fetal anomalies, and the perinatal outcome. RESULTS: The prevalence of polyhydramnios in this study is lower (0.15% AFI > 24 cm and 0.36% AFV > 8 cm) than in previous studies. The association between polyhydramnios, maternal diabetes mellitus (10.8%), fetal abnormalities (5.4%) and fetal macrosomia (10.8%) was also lower than in past reports. There was a better overall fetal outcome compared with previous studies and no perinatal deaths were seen. CONCLUSIONS: In this study, the prevalence of polyhydramnios in the third trimester was lower than in previous studies, as well as being associated with a better prognosis. This may have been the result of a combination of several factors. These include the introduction of multi-level ultrasound screening for fetal abnormality, and the improved care of diabetic women, and mothers with rhesus iso-immunisation.

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