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The Elliott-Yafet theory of spin relaxation in nonmagnetic metals predicts proportionality between spin and momentum relaxation times for scattering centers such as phonons. Here, we test this theory in Al nanowires over a very large thickness range (8.5-300 nm), finding that the Elliott-Yafet proportionality "constant" for phonon scattering in fact exhibits a large, unanticipated finite-size effect. Supported by analytical and numerical modeling, we explain this via strong phonon-induced spin relaxation at surfaces and interfaces, driven in particular by enhanced spin-orbit coupling.
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Some individuals are at risk of anti-D alloimmunization if they inherit D antigens that are qualitatively and/or quantitatively different than wild-type D. We hypothesized that patients who showed serologically inconsistent, weak, or historically discordant D typing results by microplate direct agglutination (MDA) on NEO or Echo (Immucor, Norcross, GA) might be at risk of carrying RHD allelic variants. The present study was designed to evaluate patients with RHD allelic variants if they presented with weakly reactive D typing results on the NEO or Echo. Patients were selected for RHD genotyping if their specimens showed weak reactivity with either series 4 or series 5 anti-D typing reagent, if the strength of reactivity was ≤1+ on the NEO or Echo, or if historical or current D typing results were discordant with current results. Patients selected for RHD genotyping were also tested by saline tube testing using the same anti-D series 4 and 5 reagents. Genotyping was performed by the Immucor genotyping laboratory in Warren, NJ. Of 80 patients whose samples met study inclusion, 52 (65.0%) were found to have RHD allelic variants. Sixteen patients (20.0%) expressed possible Ceppellini effect reactivity. Most importantly, 51.25 percent of the patients who presented with weakly reactive D typing results by MDA testing on the NEO (≤1+) or Echo (≤1+) had RHD allelic variants that were associated with the potential for anti-D alloimmunization. Laboratories that use MDA testing on the Neo or Echo for D typing should consider that female patients of childbearing age might be at risk of anti-D alloimmunization if they are classified as D+ based on weakly reactive D typing results.Some individuals are at risk of anti-D alloimmunization if they inherit D antigens that are qualitatively and/or quantitatively different than wild-type D. We hypothesized that patients who showed serologically inconsistent, weak, or historically discordant D typing results by microplate direct agglutination (MDA) on NEO or Echo (Immucor, Norcross, GA) might be at risk of carrying RHD allelic variants. The present study was designed to evaluate patients with RHD allelic variants if they presented with weakly reactive D typing results on the NEO or Echo. Patients were selected for RHD genotyping if their specimens showed weak reactivity with either series 4 or series 5 anti-D typing reagent, if the strength of reactivity was ≤1+ on the NEO or Echo, or if historical or current D typing results were discordant with current results. Patients selected for RHD genotyping were also tested by saline tube testing using the same anti-D series 4 and 5 reagents. Genotyping was performed by the Immucor genotyping laboratory in Warren, NJ. Of 80 patients whose samples met study inclusion, 52 (65.0%) were found to have RHD allelic variants. Sixteen patients (20.0%) expressed possible Ceppellini effect reactivity. Most importantly, 51.25 percent of the patients who presented with weakly reactive D typing results by MDA testing on the NEO (≤1+) or Echo (≤1+) had RHD allelic variants that were associated with the potential for anti-D alloimmunization. Laboratories that use MDA testing on the Neo or Echo for D typing should consider that female patients of childbearing age might be at risk of anti-D alloimmunization if they are classified as D+ based on weakly reactive D typing results.
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Aglutinação , Sistema do Grupo Sanguíneo Rh-Hr , Alelos , Feminino , Genótipo , Humanos , Sistema do Grupo Sanguíneo Rh-Hr/genética , Solução SalinaRESUMO
BACKGROUND: Temporal and dose-response relationships between allied health (AH) and recovery in the acute phase following lower limb (LL) arthroplasty are unclear. This systematic review investigates whether early commencement, additional therapy and/or weekend AH affects length of stay (LOS) and patient outcomes in the acute phase following LL arthroplasty. METHODS: Electronic databases were searched in February 2015. Studies were included if they evaluated any of the following aspects of AH for adults following LL arthroplasty in the acute phase: Early compared to later therapy commencement; Additional therapy; or a 6- or 7-day service compared to a lesser service. RESULTS: Twenty-four studies met the inclusion criteria, of which 19 investigated effects of physical therapy (PT) alone. Earlier PT reduced LOS (WMD = -1.23 days; 95% CI, -2.16 to -0.30) and resulted in higher probability of discharge directly home (relative risk = 1.45; 95% CI, 1.26-1.67). Addition of weekend PT reduced LOS (WMD = -1.04 days; 95% CI, -1.66 to -0.41) and improved function (SMD = 0.37; 95% CI, 0.02-0.73). Increasing PT from once to twice daily did not affect LOS (WMD = -0.35 days; 95% CI, -0.96-0.26) or function (SMD = 0.31; 95% CI, -0.06-0.71). DISCUSSION: Early PT commencement and a weekend service may produce favorable outcomes following LL arthroplasty when baseline LOS is 4 days or more. Redistributing PT resources to commence as early as day of surgery regardless of weekday may accelerate postoperative recovery. Current, high quality research is needed to confirm these findings.
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Modalidades de Fisioterapia , Artroplastia do Joelho , Humanos , Tempo de Internação , Extremidade Inferior , Alta do PacienteRESUMO
OBJECTIVE: To assess the frequency of obstructive sleep apnoea among women with and without hypertensive disorders of pregnancy. DESIGN: Cohort study. SETTING: Obstetric clinics at an academic medical centre. POPULATION: Pregnant women with hypertensive disorders (chronic hypertension, gestational hypertension, or pre-eclampsia) and women who were normotensive. METHODS: Women completed a questionnaire about habitual snoring and underwent overnight ambulatory polysomnography. MAIN OUTCOME MEASURES: The presence and severity of obstructive sleep apnoea. RESULTS: Obstructive sleep apnoea was found among 21 of 51 women with hypertensive disorders (41%), but in only three of 16 women who were normotensive (19%, chi-square test, P=0.005). [Author correction added on 16 June 2014, after first online publication: Results mentioned in the abstract were amended.] Non-snoring women with hypertensive disorders typically had mild obstructive sleep apnoea, but >25% of snoring women with hypertensive disorders had moderate to severe obstructive sleep apnoea. Among women with hypertensive disorders, the mean apnoea/hypopnoea index was substantially higher in snorers than in non-snorers (19.9±34.1 versus 3.4±3.1, P=0.013), and the oxyhaemoglobin saturation nadir was significantly lower (86.4±6.6 versus 90.2±3.5, P=0.021). Among women with hypertensive disorders, after stratification by obesity, the pooled relative risk for obstructive sleep apnoea in snoring women with hypertension compared with non-snoring women with hypertension was 2.0 (95% CI 1.4-2.8). CONCLUSIONS: Pregnant women with hypertension are at high risk for unrecognised obstructive sleep apnoea. Although longitudinal and intervention studies are urgently needed, given the known relationship between obstructive sleep apnoea and hypertension in the general population, it would seem pertinent that hypertensive pregnant women who snore should be tested for obstructive sleep apnoea, a condition believed to cause or promote hypertension.
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Hipertensão Induzida pela Gravidez/epidemiologia , Hipertensão/epidemiologia , Complicações na Gravidez/epidemiologia , Apneia Obstrutiva do Sono/epidemiologia , Ronco/epidemiologia , Adulto , Estudos de Coortes , Feminino , Humanos , Polissonografia , Gravidez , Índice de Gravidade de Doença , Apneia Obstrutiva do Sono/diagnóstico , Inquéritos e Questionários , Adulto JovemRESUMO
INTRODUCTION: The utilisation of laparoscopic appendicectomy (LA) in children remains contentious despite the well-recognised advantages of laparoscopic surgery. The purpose of this study was to compare intraoperative and postoperative outcomes in LA and open appendicectomy (OA) when performed by adult general surgeons outside specialist paediatric practice in younger children. METHODS: A retrospective review of all patients under the age of 13 who underwent LA for suspected appendicitis over a two-year period was conducted. These were case-matched with an equivalent number of patients who underwent OA during the same period. Intraoperative and postoperative outcomes were compared. RESULTS: Fifty-one patients underwent LA during the study period. Patient demographics were statistically equivalent with the OA cohort. A statistically significant longer median operating time (58 vs 49min) was noted in the LA group, but intraoperative outcomes were otherwise comparable. LA, when compared with OA, was associated with a significant improvement in postoperative length of stay (2 vs 3 days, p < 0.001), postoperative complication rate (0% vs 6%, p = 0.01), negative appendicectomy rate (3.9% vs 17.6%, p < 0.001) and 30-day readmission rate (0% vs 5.9%, p = 0.03). No patients in the LA group required conversion to open surgery. CONCLUSION: LA can be safely delivered by adult general surgeons to younger paediatric populations outside the setting of paediatric specialist practice, with statistically significant improvements in postoperative outcomes noted when compared with OA. These findings are of importance in the current healthcare context where adult general surgeons continue to perform the majority of paediatric appendicectomies.
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BACKGROUND: Frailty reduction and reversal have been addressed successfully among older populations within community settings. However, these findings may not be applicable to residential care settings, largely due to the complex and multidimensional nature of the condition. Relatively, few attempts at frailty prevention exist in residential settings. This review aims to identify and describe best practice models of care for addressing frailty among older populations in residential care settings. This research also sets out to explore the impact of multidisciplinary health service delivery models on health outcomes such as mortality, hospitalisations, quality of life, falls and frailty. METHODS: A scoping review of the literature was conducted to address the project objectives. Reference lists of included studies, bibliographic databases and the grey literature were systematically searched for literature reporting multidisciplinary, multidimensional models of care for frailty. RESULTS: The scoping review found no interventions that met the inclusion criteria. Of the 704 articles screened, 664 were excluded as not relevant. Forty articles were fully assessed, and while no eligible studies were found, relevant data were extracted from 10 near-eligible studies that reported single disciplines or single dimensions rather than a model of care. The physical, nutritional, medicinal, social and cognitive aspects of the near eligible studies have been discussed as playing a key role in frailty reduction or prevention care models. CONCLUSION: This review has identified a paucity of interventions for addressing and reducing frailty in residential care settings. High-quality studies investigating novel models of care for addressing frailty in residential care facilities are required to address this knowledge gap. Similarly, there is a need to develop and validate appropriate screening and assessment tools for frailty in residential care populations. Health service providers and policy-makers should also increase their awareness of frailty as a dynamic and reversible condition. While age is a non-modifiable predictor of frailty, addressing modifiable factors through comprehensive care models may help manage and prevent the physical, social and financial impacts of frailty in the ageing population.
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Idoso Fragilizado , Fragilidade , Humanos , Fragilidade/prevenção & controle , Idoso , Instituições Residenciais , Qualidade de Vida , Instituição de Longa Permanência para IdososRESUMO
We present the development of a versatile apparatus for 6.2 eV laser-based time and angle-resolved photoemission spectroscopy with micrometer spatial resolution (time-resolved µ-ARPES). With a combination of tunable spatial resolution down to â¼11 µm, high energy resolution (â¼11 meV), near-transform-limited temporal resolution (â¼280 fs), and tunable 1.55 eV pump fluence up to 3 mJ/cm2, this time-resolved µ-ARPES system enables the measurement of ultrafast electron dynamics in exfoliated and inhomogeneous materials. We demonstrate the performance of our system by correlating the spectral broadening of the topological surface state of Bi2Se3 with the spatial dimension of the probe pulse, as well as resolving the spatial inhomogeneity contribution to the observed spectral broadening. Finally, after in situ exfoliation, we performed time-resolved µ-ARPES on a â¼30 µm flake of transition metal dichalcogenide WTe2, thus demonstrating the ability to access ultrafast electron dynamics with momentum resolution on micro-exfoliated materials.
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Management of severe sepsis, an acute illness with high morbidity and mortality, suffers from the lack of effective biomarkers and largely empirical predictions of disease progression and therapeutic responses. We conducted a genome-wide association study using a large randomized clinical trial cohort to discover genetic biomarkers of response to therapy and prognosis utilizing novel approaches, including combination markers, to overcome limitations of single-marker analyses. Sepsis prognostic models were dominated by clinical variables with genetic markers less informative. In contrast, evidence for gene-gene interactions were identified for sepsis treatment responses with genetic biomarkers dominating models for predicting therapeutic responses, yielding candidates for replication in other cohorts.
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Biomarcadores Farmacológicos , Marcadores Genéticos , Proteína C/genética , Sepse/tratamento farmacológico , Sepse/genética , Progressão da Doença , Epistasia Genética , Estudo de Associação Genômica Ampla , Humanos , Polimorfismo de Nucleotídeo Único , Prognóstico , Ensaios Clínicos Controlados Aleatórios como Assunto , Proteínas Recombinantes/genética , Sepse/patologiaRESUMO
BACKGROUND AND AIM: Current treatment for irritable bowel syndrome (IBS) is suboptimal. Fermentable oligo-, di-, mono-saccharides and polyols (FODMAPs) may trigger gastrointestinal symptoms in IBS patients. Our aim was to determine whether a low FODMAP diet improves symptoms in IBS patients. METHODS: Irritable bowel syndrome patients, who had performed hydrogen/methane breath testing for fructose and lactose malabsorption and had received dietary advice regarding the low FODMAP diet, were included. The effect of low FODMAP diet was prospectively evaluated using a symptom questionnaire. Furthermore, questions about adherence and satisfaction with symptom improvement, dietary advice and diet were assessed. RESULTS: Ninety patients with a mean follow up of 15.7 months were studied. Most symptoms including abdominal pain, bloating, flatulence and diarrhoea significantly improved (p < 0.001 for all). 75.6%, 37.8% and 13.3% of patients had fructose, lactose malabsorption or small intestinal bacterial overgrowth respectively. Fructose malabsorption was significantly associated with symptom improvement (abdominal pain odds ratio (OR) 7.09 [95% confidence interval (CI) 2.01-25.0], bloating OR 8.71 (95% CI 2.76-27.5), flatulence OR 7.64 (95% CI 2.53-23.0) and diarrhoea OR 3.39 (95% CI 1.17-9.78), p < 0.029 for all). Most patients (75.6%) were adherent to the diet, which was associated with symptom improvement (abdominal pain, bloating, flatulence and diarrhoea all significantly associated with adherence, r > 0.27, p < 0.011). Most patients (72.1%) were satisfied with their symptoms. CONCLUSIONS: The low FODMAP diet shows efficacy for IBS patients. The current strategy of breath testing and dietary advice provides a good basis to understand and adhere to the diet.
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Síndrome do Intestino Irritável/dietoterapia , Síndromes de Malabsorção/dietoterapia , Dor Abdominal/dietoterapia , Dor Abdominal/etiologia , Testes Respiratórios , Diarreia/dietoterapia , Diarreia/etiologia , Feminino , Flatulência/dietoterapia , Flatulência/etiologia , Frutose/farmacocinética , Intolerância à Frutose/complicações , Intolerância à Frutose/dietoterapia , Humanos , Síndrome do Intestino Irritável/etiologia , Lactose/farmacocinética , Intolerância à Lactose/complicações , Intolerância à Lactose/dietoterapia , Síndromes de Malabsorção/complicações , Masculino , Pessoa de Meia-Idade , Cooperação do Paciente , Satisfação do Paciente , Estudos Prospectivos , Resultado do TratamentoRESUMO
BACKGROUND: Prostate cancer (PrCa) is one of the most common cancers affecting men but its aetiology is poorly understood. Family history of PrCa, particularly at a young age, is a strong risk factor. There have been previous reports of increased PrCa risk in male BRCA1 mutation carriers in female breast cancer families, but there is a controversy as to whether this risk is substantiated. We sought to evaluate the role of germline BRCA1 mutations in PrCa predisposition by performing a candidate gene study in a large UK population sample set. METHODS: We screened 913 cases aged 3686 years for germline BRCA1 mutation, with the study enriched for cases with an early age of onset. We analysed the entire coding region of the BRCA1 gene using Sanger sequencing. Multiplex ligation-dependent probe amplification was also used to assess the frequency of large rearrangements in 460 cases. RESULTS: We identified 4 deleterious mutations and 45 unclassified variants (UV). The frequency of deleterious BRCA1 mutation in this study is 0.45%; three of the mutation carriers were affected at age 65 years and one developed PrCa at 69 years. Using previously estimated population carrier frequencies, deleterious BRCA1 mutations confer a relative risk of PrCa of ~3.75-fold, (95% confidence interval 1.029.6) translating to a 8.6% cumulative risk by age 65. CONCLUSION: This study shows evidence for an increased risk of PrCa in men who harbour germline mutations in BRCA1. This could have a significant impact on possible screening strategies and targeted treatments.
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Genes BRCA1 , Mutação em Linhagem Germinativa , Neoplasias da Próstata/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias da Próstata/etiologia , RiscoRESUMO
In domain wall (DW) excitation experiments, nonlinearity (NL) intrinsic to the DW dynamics is often hard to distinguish from perturbation due to the confining potential or DW distortion. Here we numerically investigate the dynamic oscillations of magnetostatically coupled DWs: a system well understood in the quasistatic limit. NL is observed, even for a harmonic potential, due to the intrinsic DW motion. This behavior is principally dependent on terms normally associated with the DW canonical momentum and is in contrast with a NL restoring potential. This NL is not observable in quasistatic measurements, relatively insensitive to the confining potential, and may be tuned by the nanowire parameters. The shown NLs are present in any DW restoring potential and must be accounted for when probing DW potential landscapes.
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BACKGROUND: In a rural Irish hospital, a simple clinical score (SCS) determined at the time of admission enabled stratification of acute general medical admissions into five categories that were associated incrementally with patients' immediate and 30-day mortality. The aim of this study was to examine the representative performance of this SCS in predicting the outcomes of general medical admissions to an Australian teaching hospital. METHODS: A retrospective chart review was undertaken of a representative sample from 480 admissions in 2007 to an urban university teaching hospital in Australia. The SCS was calculated and related to that patient's outcome in terms of mortality, length of stay, nursing home placement on discharge, the occurrence of medical emergency team call and intensive care unit transfer. These data were compared, where possible, with the outcomes reported in the Irish hospital. RESULTS: Four hundred and seventeen complete sets of data allowed calculation of the SCS. There were significant linear correlations of the SCS (divided into quintiles) and patients' in-hospital and 30-day mortality, their length of stay and their discharge to a nursing home. There was no association of the SCS and the patients' readmission rate, intensive care unit transfer rate or likelihood of a medical emergency team call. The significant trends replicated those from the Irish hospital. CONCLUSION: The SCS can predict significant outcomes for general medical admissions in an Australian hospital despite obvious differences to the hospital of its derivation. A wider study of Australasian hospitals and the performance of the SCS as a predictor of general medical admission outcomes is underway.
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Mortalidade Hospitalar/tendências , Tempo de Internação/tendências , Admissão do Paciente/tendências , Índice de Gravidade de Doença , Adulto , Idoso , Idoso de 80 Anos ou mais , Austrália/epidemiologia , Estudos de Coortes , Feminino , Hospitalização/tendências , Hospitais de Ensino/tendências , Humanos , Masculino , Pessoa de Meia-Idade , Estudos RetrospectivosRESUMO
The purpose of this study was to investigate the association between habitual snoring (HS), middle ear disease (MED), and speech problems in children with cleft palate. This cross-sectional study included children aged 2.0-7.9 years with non-syndromic cleft palate anomalies. Parents completed the Pediatric Sleep Questionnaire and a questionnaire about MED. Audiograms and speech assessment were also conducted. Ninety-five children were enrolled; 15.2% of families reported HS, 97.6% MED, and 17.1% speech problems. HS (37.5% vs 10.3%, P = 0.007) and early episodes of MED (92.3% vs 58.2%, P = 0.021) were more likely to be reported for children with isolated cleft palate when compared to those with cleft lip and palate. Children with cleft lip and palate had a higher frequency of MED with effusion compared to those with Robin sequence (86.4% vs 57.1%, P = 0.049). The odds ratio for HS in children with ≥1 episode of MED in the last year was 7.37 (95% confidence interval 1.55-35.15, P = 0.012). There was a trend for children with speech problems reported by parents to have HS (30.8% vs 11.5%, P= 0.076). Anatomical factors play a role in the frequency of upper airway symptoms in children with cleft palate. A recent history of at least one episode of MED was associated with an increased frequency of HS.
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Fenda Labial , Fissura Palatina , Otopatias , Criança , Pré-Escolar , Fenda Labial/complicações , Fissura Palatina/complicações , Estudos Transversais , Otopatias/complicações , Humanos , Ronco/complicações , Ronco/epidemiologia , FalaRESUMO
We report on the electronic and magnetic properties of superconductor-ferromagnet heterostructures fabricated by electron beam evaporation on to unheated thermally oxidised Si substrates. Polycrystalline Nb thin films (5 to 50 nm thick) were shown to possess reliably high superconducting critical temperatures ([Formula: see text]), which correlate well with the residual resistivity ratio (RRR) of the film. These properties improved during ex-situ annealing, resulting in [Formula: see text] and [Formula: see text]RRR increases of up 2.2 K ([Formula: see text] 40% of the pre-annealed [Formula: see text]) and 0.8 ([Formula: see text] 60% of the pre-annealed RRR) respectively. Nb/Pt/Co/Pt heterostructures showed substantial perpendicular anisotropy in the ultrathin limit (≤ 2.5 nm), even in the extreme limit of Pt(0.8 nm)/Co(1 nm)/Pt(0.6 nm). These results point to the use of electron beam evaporation as route to line-of-sight deposited, low-thickness, high quality Nb-based superspintronic multilayers.
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BACKGROUND: The ratio of digit lengths is fixed in utero, and may be a proxy indicator for prenatal testosterone levels. METHODS: We analysed the right-hand pattern and prostate cancer risk in 1524 prostate cancer cases and 3044 population-based controls. RESULTS: Compared with index finger shorter than ring finger (low 2D : 4D), men with index finger longer than ring finger (high 2D : 4D) showed a negative association, suggesting a protective effect with a 33% risk reduction (odds ratio (OR) 0.67, 95% confidence interval (CI) 0.57-0.80). Risk reduction was even greater (87%) in age group <60 (OR 0.13, 95% CI 0.09-0.21). CONCLUSION: Pattern of finger lengths may be a simple marker of prostate cancer risk, with length of 2D greater than 4D suggestive of lower risk.
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Dedos/anatomia & histologia , Mãos/fisiologia , Neoplasias da Próstata/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias da Próstata/etiologia , Fatores de RiscoRESUMO
BACKGROUND: A family history of prostate cancer (PrCa) is a strong risk factor for the disease, indicating that inherited factors are important in this disease. We previously estimated that about 2% of PrCa cases diagnosed ≤ 55 years harbour a BRCA2 mutation and PrCa among BRCA2 carriers has been shown to be more aggressive, with poorer survival. METHODS: To further evaluate the role of BRCA2 in PrCa predisposition, we screened 1864 men with PrCa aged between 36 and 88 years. We analysed the BRCA2 gene using a novel high-throughput multiplex fluorescence heteroduplex detection system developed for the ABI3130xl genetic analyzer. RESULTS: We identified 19 protein-truncating mutations, 3 in-frame deletions and 69 missense variants of uncertain significance (UV) in our sample set. All the carriers of truncating mutations developed PrCa at ≤ 65 years, with a prevalence of BRCA2 mutation of 1.20% for cases in this age group. CONCLUSION: Based on the estimated frequency of BRCA2 mutations in the United Kingdom we estimate that germline mutations in the BRCA2 gene confer an â¼ 8.6-fold increased risk of PrCa by age 65, corresponding to an absolute risk of â¼ 15% by age 65. These results suggest that routine testing of early onset PrCa cases for germline BRCA2 mutations will further help to refine the prevalence and risk associated with BRCA2 mutations and may be useful for guiding management options.
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Idade de Início , Genes BRCA2 , Testes Genéticos , Neoplasias da Próstata/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Análise de SobrevidaRESUMO
Genome-wide association studies (GWAS) have identified more than 30 prostate cancer (PrCa) susceptibility loci. One of these (rs2735839) is located close to a plausible candidate susceptibility gene, KLK3, which encodes prostate-specific antigen (PSA). PSA is widely used as a biomarker for PrCa detection and disease monitoring. To refine the association between PrCa and variants in this region, we used genotyping data from a two-stage GWAS using samples from the UK and Australia, and the Cancer Genetic Markers of Susceptibility (CGEMS) study. Genotypes were imputed for 197 and 312 single nucleotide polymorphisms (SNPs) from HapMap2 and the 1000 Genome Project, respectively. The most significant association with PrCa was with a previously unidentified SNP, rs17632542 (combined P = 3.9 × 10(-22)). This association was confirmed by direct genotyping in three stages of the UK/Australian GWAS, involving 10,405 cases and 10,681 controls (combined P = 1.9 × 10(-34)). rs17632542 is also shown to be associated with PSA levels and it is a non-synonymous coding SNP (Ile179Thr) in KLK3. Using molecular dynamic simulation, we showed evidence that this variant has the potential to introduce alterations in the protein or affect RNA splicing. We propose that rs17632542 may directly influence PrCa risk.
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Predisposição Genética para Doença , Calicreínas/genética , Neoplasias da Próstata/genética , RNA Mensageiro/genética , Estudo de Associação Genômica Ampla , Humanos , Masculino , Simulação de Dinâmica Molecular , Polimorfismo de Nucleotídeo Único , Antígeno Prostático Específico/sangueRESUMO
Modern fabrication technology has enabled the study of submicron ferromagnetic strips with a particularly simple domain structure, allowing single, well-defined domain walls to be isolated and characterized. However, these domain walls have complex field-driven dynamics. The wall velocity initially increases with field, but above a certain threshold the domain wall abruptly slows down, accompanied by periodic transformations of the domain wall structure. This behaviour is potentially detrimental to the speed and proper functioning of proposed domain-wall-based devices, and although methods for suppression of the breakdown have been demonstrated in simulations, a convincing experimental demonstration is lacking. Here, we show experimentally that a series of cross-shaped traps acts to prevent transformations of the domain wall structure and increase the domain wall velocity by a factor of four compared to the maximum velocity on a plain strip. Our results suggest a route to faster and more reliable domain wall devices for memory, logic and sensing.
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Domain wall (DW) pinning in ferromagnetic nanowires is in general a complex process. Distortions of the DW shape make quantitative agreement between modeling and experiment difficult. Here we demonstrate pinning using nanometer scale localized stray fields. This type of interaction gives well-characterized, tailorable potential landscapes that do not appreciably distort the DW. Our experimental results are in excellent quantitative agreement with an Arrhenius-Néel model of depinning--a result only possible when the modeled potential profile agrees fully with that experienced by the DW.