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1.
Eur J Prosthodont Restor Dent ; 25(4): 220-227, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-29182212

RESUMO

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.


Assuntos
Resinas Compostas , Corrosão Dentária/métodos , Restauração Dentária Permanente , Adesivos Dentinários , Cimentos de Resina , Feminino , Humanos , Masculino , Fatores de Tempo
2.
Eur J Prosthodont Restor Dent ; 25(1): 35-41, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28569449

RESUMO

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.


Assuntos
Resinas Compostas , Esmalte Dentário , Corrosão Dentária/métodos , Nanopartículas , Restauração Dentária Permanente , Adesivos Dentinários , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo
3.
BJOG ; 122(10): 1370-6, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25639820

RESUMO

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.


Assuntos
Aneuploidia , Gonadotropina Coriônica Humana Subunidade beta/sangue , Testes para Triagem do Soro Materno , Placenta Acreta/diagnóstico , Primeiro Trimestre da Gravidez/sangue , Proteína Plasmática A Associada à Gravidez/metabolismo , Adulto , Biomarcadores/sangue , Estudos de Casos e Controles , Feminino , Seguimentos , Humanos , Placenta Acreta/sangue , Placenta Prévia/sangue , Placenta Prévia/diagnóstico , Gravidez , Estudos Prospectivos
5.
Int J Biochem Cell Biol ; 40(5): 892-900, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18054267

RESUMO

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.


Assuntos
Citocinese , Distroglicanas/fisiologia , Citoesqueleto de Actina/química , Animais , Ciclo Celular , Distroglicanas/análise , Distroglicanas/química , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Células HeLa , Humanos , Camundongos , Estrutura Terciária de Proteína , Células Swiss 3T3
6.
AJNR Am J Neuroradiol ; 38(7): 1399-1404, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28495950

RESUMO

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.


Assuntos
Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/etiologia , Artérias Carótidas/anormalidades , Doenças das Artérias Carótidas/complicações , Doenças das Artérias Carótidas/diagnóstico por imagem , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/etiologia , Adolescente , Adulto , Negro ou Afro-Americano , Isquemia Encefálica/epidemiologia , Doenças das Artérias Carótidas/epidemiologia , Angiografia Cerebral , Feminino , Lateralidade Funcional , Humanos , Angiografia por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Pescoço/diagnóstico por imagem , Prevalência , Estudos Retrospectivos , Fatores de Risco , Fatores Sexuais , Acidente Vascular Cerebral/epidemiologia , Adulto Jovem
7.
J Hazard Mater ; 317: 97-107, 2016 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-27262277

RESUMO

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.

8.
J Invest Dermatol ; 82(4): 362-6, 1984 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-6323588

RESUMO

Several papillomas from a single patient who exhibited an unusual immune deficiency syndrome were analyzed for the presence of specific human papillomavirus (HPV) types. Preliminary analysis indicated that the HPV DNA species present in each of these tissues was quite unlike any of the previously characterized HPV types. In order to more rigorously analyze the HPV from this patient we have isolated the HPV DNA by molecularly cloning it into a bacteriophage lambda vector and have constructed a detailed restriction endonuclease map. Comparative hybridization studies using S1 nuclease analyses showed 6% or less nucleotide sequence homology of this viral DNA with HPV types 1, 2, 3, 4, 5, 6, or an HPV-11, molecularly cloned in this laboratory. Moreover, Southern blot analyses under stringent hybridization conditions revealed little, if any, hybridization to HPV types 1, 2, 4, 5, 7, 8, 10, 11, HPV-EV isolated from a patient with epidermodysplasia verruciformis (EV), or 2 previously described HPVs (HPV-P and HPV-PW) related to HPV-3. There was, however, a very weak sequence homology detected with HPV-6 and an extremely weak homology to HPV-3. No filter hybridization was observed with the recently characterized HPVs 9 or -12 to -24. These data accumulatively indicate that the HPV species from this immunosuppressed patient represents a new, hitherto unidentified HPV type.


Assuntos
Clonagem Molecular , Síndromes de Imunodeficiência/microbiologia , Papillomaviridae/isolamento & purificação , Animais , DNA Viral/genética , DNA Viral/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade , Hibridização de Ácido Nucleico , Neoplasias Cutâneas/microbiologia , Infecções Tumorais por Vírus/microbiologia
9.
Arch Med Res ; 26(2): 121-6, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7620276

RESUMO

The occurrence of respiratory syncytial virus (RSV) subtypes in Mexico City was studied by searching for the virus in nasopharyngeal aspirates of 82 infants, less than 12 months of age, hospitalized for acute lower respiratory tract disease with diagnosis of bronchitis, bronchiolitis, pneumonia and laryngotracheobronchitis. The presence of respiratory virus was determined by observation of cytopathic effect in cell monolayers; samples which produced a clear syncytia were considered positive and were treated with anti-respiratory syncytial virus serum. Viral infectivity was neutralized in 21 samples which were regarded as having RSV. These specimens were characterized into subtypes A and B with specific monoclonals by indirect immunofluorescence. Subtype A predominated over subtype B, 19 vs. 2. Patients with pneumonia and laryngotracheobronchitis had subtype A and both subtypes were found in infants with bronchitis and bronchiolitis.


Assuntos
Infecções por Vírus Respiratório Sincicial/virologia , Vírus Sinciciais Respiratórios/classificação , Infecções Respiratórias/virologia , Doença Aguda , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Antivirais/imunologia , Carcinoma de Células Escamosas/patologia , Chlorocebus aethiops , Efeito Citopatogênico Viral , Feminino , Humanos , Lactente , Recém-Nascido , Neoplasias Laríngeas/patologia , Masculino , México/epidemiologia , Nasofaringe/virologia , Testes de Neutralização , Coelhos , Infecções por Vírus Respiratório Sincicial/epidemiologia , Vírus Sinciciais Respiratórios/imunologia , Vírus Sinciciais Respiratórios/isolamento & purificação , Infecções Respiratórias/epidemiologia , Células Tumorais Cultivadas , Células Vero
10.
J Dent ; 41(11): 992-9, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23954574

RESUMO

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.


Assuntos
Cerâmica/química , Materiais Dentários/química , Planejamento de Dentadura , Prótese Parcial Fixa , Ítrio/química , Zircônio/química , Adulto , Pesquisa Participativa Baseada na Comunidade , Desenho Assistido por Computador , Dente Suporte , Colagem Dentária , Cárie Dentária/classificação , Adaptação Marginal Dentária , Falha de Restauração Dentária , Facetas Dentárias , Sensibilidade da Dentina/classificação , Reparação em Dentadura , Retenção de Dentadura , Seguimentos , Gengiva/anatomia & histologia , Humanos , Propriedades de Superfície , Análise de Sobrevida
12.
Dent Mater ; 28(3): 229-36, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22244732

RESUMO

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.


Assuntos
Porcelana Dentária , Prótese Parcial Fixa , Odontologia Geral , Adulto , Pesquisa Participativa Baseada na Comunidade , Feminino , Humanos , Masculino , Prática Privada , Cimentos de Resina , Reino Unido , Ítrio , Zircônio
13.
Dent Mater ; 27(7): 622-30, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21514654

RESUMO

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.


Assuntos
Resinas Compostas , Restauração Dentária Permanente , Odontologia Geral , Siloxanas , Dente Pré-Molar , Resinas Compostas/química , Adaptação Marginal Dentária , Análise do Estresse Dentário , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dente Molar , Polimerização , Resinas de Silorano , Siloxanas/química , Reino Unido
16.
Northwest Dent ; 49(5): 311-2, 1970.
Artigo em Inglês | MEDLINE | ID: mdl-5274793
17.
Northwest Dent ; 49(6): 377-8, 1970.
Artigo em Inglês | MEDLINE | ID: mdl-5277870
18.
Br Dent J ; 205(9): 477-82, 2008 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-18997700

RESUMO

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.


Assuntos
Desenho Assistido por Computador , Porcelana Dentária , Desgaste de Restauração Dentária , Planejamento de Dentadura , Prótese Parcial Fixa , Odontologia Geral/métodos , Adulto , Inquéritos de Saúde Bucal , Falha de Restauração Dentária , Restauração Dentária Permanente/métodos , Análise do Estresse Dentário , Seguimentos , Humanos , Arcada Parcialmente Edêntula/reabilitação , Cimentos de Resina , Resultado do Tratamento , Reino Unido , Ítrio , Zircônio
19.
Int J Obes (Lond) ; 30(1): 176-82, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16158084

RESUMO

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.


Assuntos
Índice de Massa Corporal , Comportamento Alimentar/fisiologia , Antropometria , Criança , Desenvolvimento Infantil/fisiologia , Ritmo Circadiano/fisiologia , Registros de Dieta , Ingestão de Energia/fisiologia , Feminino , Seguimentos , Crescimento/fisiologia , Humanos , Estudos Longitudinais , Sobrepeso/fisiologia , Fatores Socioeconômicos
20.
Am J Obstet Gynecol ; 181(1): 131-6, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10411808

RESUMO

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

Assuntos
Biomarcadores/sangue , Inibinas/sangue , Pré-Eclâmpsia/sangue , Pré-Eclâmpsia/diagnóstico , Diagnóstico Pré-Natal , Feminino , Humanos , Razão de Chances , Valor Preditivo dos Testes , Gravidez , Segundo Trimestre da Gravidez , Estudos Retrospectivos , Sensibilidade e Especificidade
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