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BACKGROUND: In laboratory animals, exposure to most general anaesthetics leads to neurotoxicity manifested by neuronal cell death and abnormal behaviour and cognition. Some large human cohort studies have shown an association between general anaesthesia at a young age and subsequent neurodevelopmental deficits, but these studies are prone to bias. Others have found no evidence for an association. We aimed to establish whether general anaesthesia in early infancy affects neurodevelopmental outcomes.METHODS: In this international, assessor-masked, equivalence, randomised, controlled trial conducted at 28 hospitals in Australia, Italy, the USA, the UK, Canada, the Netherlands, and New Zealand, we recruited infants of less than 60 weeks' postmenstrual age who were born at more than 26 weeks' gestation and were undergoing inguinal herniorrhaphy, without previous exposure to general anaesthesia or risk factors for neurological injury. Patients were randomly assigned (1:1) by use of a web-based randomisation service to receive either awake-regional anaesthetic or sevoflurane-based general anaesthetic. Anaesthetists were aware of group allocation, but individuals administering the neurodevelopmental assessments were not. Parents were informed of their infants group allocation upon request, but were told to mask this information from assessors. The primary outcome measure was full-scale intelligence quotient (FSIQ) on the Wechsler Preschool and Primary Scale of Intelligence, third edition (WPPSI-III), at 5 years of age. The primary analysis was done on a per-protocol basis, adjusted for gestational age at birth and country, with multiple imputation used to account for missing data. An intention-to-treat analysis was also done. A difference in means of 5 points was predefined as the clinical equivalence margin. This completed trial is registered with ANZCTR, number ACTRN12606000441516, and ClinicalTrials.gov, number NCT00756600.FINDINGS: Between Feb 9, 2007, and Jan 31, 2013, 4023 infants were screened and 722 were randomly allocated: 363 (50%) to the awake-regional anaesthesia group and 359 (50%) to the general anaesthesia group. There were 74 protocol violations in the awake-regional anaesthesia group and two in the general anaesthesia group. Primary outcome data for the per-protocol analysis were obtained from 205 children in the awake-regional anaesthesia group and 242 in the general anaesthesia group. The median duration of general anaesthesia was 54 min (IQR 41-70). The mean FSIQ score was 99·08 (SD 18·35) in the awake-regional anaesthesia group and 98·97 (19·66) in the general anaesthesia group, with a difference in means (awake-regional anaesthesia minus general anaesthesia) of 0·23 (95% CI -2·59 to 3·06), providing strong evidence of equivalence. The results of the intention-to-treat analysis were similar to those of the per-protocol analysis.INTERPRETATION: Slightly less than 1 h of general anaesthesia in early infancy does not alter neurodevelopmental outcome at age 5 years compared with awake-regional anaesthesia in a predominantly male study population.FUNDING: US National Institutes of Health, US Food and Drug Administration, Thrasher Research Fund, Australian National Health and Medical Research Council, Health Technologies Assessment-National Institute for Health Research (UK), Australian and New Zealand College of Anaesthetists, Murdoch Children's Research Institute, Canadian Institutes of Health Research, Canadian Anesthesiologists Society, Pfizer Canada, Italian Ministry of Health, Fonds NutsOhra, UK Clinical Research Network, Perth Children's Hospital Foundation, the Stan Perron Charitable Trust, and the Callahan Estate.

Surveys are frequently used to collect data in graduate medical education (GME) settings.1 However, if a GME survey is not rigorously designed, the quality of the results is likely to be lower than desirable. In a recent editorial we introduced a framework for developing survey instruments.1 This systematic approach is intended to improve the quality of GME surveys and increase the likelihood of collecting survey data with evidence of reliability and validity. In this article we illustrate how researchers in medical education may operationalize this framework with examples from a survey we developed during the recent integration of 2 independent internal medicine (IM) residency programs.

BACKGROUND: Current estimates of the contribution of large rearrangement (LR) mutations in the BRCA1 (breast cancer 1, early onset) and BRCA2 (breast cancer 2, early onset) genes responsible for hereditary breast and ovarian cancer are based on limited studies of relatively homogeneous patient populations. The prevalence of BRCA1/2 LRs was investigated in 48,456 patients with diverse clinical histories and ancestries, referred for clinical molecular testing for suspicion of hereditary breast and ovarian cancer. METHODS: Sanger sequencing analysis was performed for BRCA1/2 and LR testing for deletions and duplications using a quantitative multiplex polymerase chain reaction assay. Prevalence data were analyzed for patients from different risk and ethnic groups between July 2007 and April 2011. Patients were designated as “high-risk” if their clinical history predicted a high prior probability, wherein LR testing was performed automatically in conjunction with sequencing. “Elective” patients did not meet the high-risk criteria, but underwent LR testing as ordered by the referring health care provider. RESULTS: Overall BRCA1/2 mutation prevalence among high-risk patients was 23.8% versus 8.2% for the elective group. The mutation profile for high-risk patients was 90.1% sequencing mutations versus 9.9% LRs, and for elective patients, 94.1% sequencing versus 5.9% LRs. This difference may reflect the bias in high-risk patients to carry mutations in BRCA1, which has a higher penetrance and frequency of LRs compared with BRCA2. There were significant differences in the prevalence and types of LRs in patients of different ancestries. LR mutations were significantly more common in Latin American/Caribbean patients. CONCLUSIONS: Comprehensive LR testing in conjunction with full gene sequencing is an appropriate strategy for clinical BRCA1/2 analysis.

Context Patients with multiple colorectal adenomas may carry germline mutations in the APC or MUTYH genes. Objectives To determine the prevalence of pathogenic APC and MUTYH mutations in patients with multiple colorectal adenomas who had undergone genetic testing and to compare the prevalence and clinical characteristics of APC and MUTYH mutation carriers. Design, Setting, and Participants Cross-sectional study conducted among 8676 individuals who had undergone full gene sequencing and large rearrangement analysis of the APC gene and targeted sequence analysis for the 2 most common MUTYH mutations (Y179C and G396D) between 2004 and 2011. Individuals with either mutation underwent full MUTYH gene sequencing. APC and MUTYH mutation prevalence was evaluated by polyp burden; the clinical characteristics associated with a pathogenic mutation were evaluated using logistic regression analyses. Main Outcome Measure Prevalence of pathogenic mutations in APC and MUTYH genes. Results Colorectal adenomas were reported in 7225 individuals; 1457 with classic polyposis (≥100 adenomas) and 3253 with attenuated polyposis (20-99 adenomas). The prevalence of pathogenic APC and biallelic MUTYH mutations was 95 of 119 (80% [95% CI, 71%-87%]) and 2 of 119 (2% [95% CI, 0.2%-6%]), respectively, among individuals with 1000 or more adenomas, 756 of 1338 (56% [95% CI, 54%-59%]) and 94 of 1338 (7% [95% CI, 6%-8%]) among those with 100 to 999 adenomas, 326 of 3253 (10% [95% CI, 9%-11%]) and 233 of 3253 (7% [95% CI, 6%-8%]) among those with 20 to 99 adenomas, and 50 of 970 (5% [95% CI, 4%-7%]) and 37 of 970 (4% [95% CI, 3%-5%]) among those with 10 to 19 adenomas. Adenoma count was strongly associated with a pathogenic mutation in multivariable analyses. Conclusions Among patients with multiple colorectal adenomas, pathogenic APC and MUTYH mutation prevalence varied considerably by adenoma count, including within those with a classic polyposis phenotype. APC mutations predominated in patients with classic polyposis, whereas prevalence of APC and MUTYH mutations was similar in attenuated polyposis. These findings require external validation.

Background In women at increased risk for breast and ovarian cancer, the identification of a BRCA1/2 mutation has important implications for screening and prevention counseling. Uncertainty regarding the role of BRCA1/2 testing in high-risk women from diverse ancestral backgrounds exists due to variability in prevalence estimates of deleterious (disease-associated) mutations in non-White populations. We examined the prevalence of BRCA1/2 mutations in an ethnically diverse group of women referred for genetic testing.

textabstractContext: Lynch syndrome is caused primarily by mutations in the mismatch repair genes MLH1 and MSH2. Objectives: To analyze MLH1/MSH2 mutation prevalence in a large cohort of patients undergoing genetic testing and to develop a clinical model to predict the likelihood of finding a mutation in at-risk patients. Design, Setting, and Participants: Personal and family history were obtained for 1914 unrelated probands who submitted blood samples starting in the year 2000 for full gene sequencing of MLH1/MSH2. Genetic analysis was performed using a combination of sequence analysis and Southern blotting. A multivariable model was developed using logistic regression in an initial cohort of 898 individuals and subsequently prospectively validated in 1016 patients. The complex model that we have named PREMM1,2 (Prediction of Mutations in MLH1 and MSH2) was developed into a Webbased tool that incorporates personal and family history of cancer and adenomas. Main Outcome Measure: Deleterious mutations in MLH1/MSH2 genes. Results: Overall, 14.5% of the probands (130/898) carried a pathogenic mutation (MLH1, 6.5%; MSH2, 8.0%) in the development cohort and 15.3% (155/1016) in the validation cohort, with 42 (27%) of the latter being large rearrangements. Strong predictors of mutations included proband characteristics (presence of colorectal cancer, especially ≥2 separate diagnoses, or endometrial cancer) and family history (especially the number of first-degree relatives with colorectal or endometrial cancer). Age at diagnosis was particularly important for colorectal cancer. The multivariable model discriminated well at external validation, with an area under the receiver operating characteristic curve of 0.80 (95% confidence interval, 0.76-0.84). Conclusions: Personal and family history characteristics can accurately predict the outcome of genetic testing in a large population at risk of Lynch syndrome. The PREMM1,2 model provides clinicians with an objective, easy-to-use tool to estimate the likelihood of finding mutations in the MLH1/MSH2 genes and may guide the strategy for molecular evaluation.

Introduction: This research protocol has been developed as part of an integrated care initiative for vulnerable families in Sydney, Australia. The aim is to develop “whole-of-government” interventions that break intergenerational cycles of disadvantage and poor life outcomes. A realist methodology will be described for the translation of empirically ‘data derived’ causal middle-range theories of social mechanisms, into health and social programme theories, whose theoretical propositions can be operationalized and studied in concrete situations using collective theory driven approaches. Theory/Methods: The research settings are in metropolitan Sydney, Australia. The design will be a longitudinal, multi-level, mixed method realist evaluation of applied programme interventions that seek to break the intergenerational cycle of social disadvantage and poor child health and developmental outcomes. The programme of research will consist of three components: 1) Operationalization of the theory and designing of programme initiatives for implementation; 2) Evaluation of the translated programme and implementation theory using Theory of Change and Realistic Evaluation; and 3) Theory Testing of realist hypotheses using both intensive and extensive critical realist research methods including realist structural modelling. Results: No applicable Discussion: The proposed programme of research will assist in translating empirical explanatory theory building to theory driven interventions. The research will be situated in socially disadvantaged regions of Sydney where the local child and family interagencies will collaborate to design and implement new initiatives that address significant disparities in early childhood development and adolescent outcomes attributed to neighbourhood circumstances, family stress and intergenerational cycles of disadvantage and poor mental health. Conclusions: Central to this protocol is the development of programme theory. Much of the theory driven and realist evaluation literature begins with existing interventions. The first task in those situations is to identify the underlying programme theory. In preparing this programme of work we were faced with the translation of causal theory to programme and implementation theory. We have proposed as a first step in this protocol the formal translation of the middle-range ‘causal’ theory into a middle-range ‘programme theory’ followed by an intervention design process based on Theory of Change approaches. Lessons learned: In preparing the protocol we have identified extensive debate concern the nature of implementation theory and programme theory. There is also on-going critical analysis of the nature of context (c), mechanisms (M) and outcomes (o) and how these might be defined and measured. Limitations: The application of realist methodologies to population health interventions is relatively new and there is little extant literature on the translational process from causal theory to programme theory. The study protocol is thus breaking new ground and it is anticipated that the approaches described will require modification. Suggestions for future research: The protocol development identified a need for further clarification of the nature of causal mechanism and programme mechanisms among the integrated care and evaluation research communities.

1542 Background: Patients with Hereditary Breast and Ovarian cancer (HBOC) or Lynch syndrome (LS) hereditary cancer syndromes are at a greater risk for developing second cancers after an initial ca...

343 Background: MYH-associated polyposis is an autosomal recessive syndrome caused by biallelic mutations in the base excision repair gene MYH. Initial reports indicated that a majority of European biallelic individuals carried two founder mutations, Y165C and G382D. A common MYH analysis strategy involves evaluation of the two founder mutations (FMs) with subsequent full sequencing only if one of the FMs is identified. This study aimed to determine the sensitivity of full MYH sequencing over the strategy described above in a cohort of individuals that has undergone genetic testing by a commercial laboratory. Methods: A retrospective analysis was performed on 1,522 individuals who had clinical MYH testing ordered either independently or in conjunction with APC gene analysis. All patients underwent MYH analysis for Y165C and G382D. Subsequent full gene sequencing was performed for all patients, except for those biallellic for the two FMs. Demographic, personal, and family cancer histories were collected on the test request form. Results: 86 biallelic individuals were identified, with 47 carrying two FMs, 18 carrying one FM and one mutation identified on sequencing, and 21 carrying biallelic mutations identified only on full sequencing. 21/86 (24.4%) biallelic MYH mutation carriers would have been missed by FM analysis only. The mutation spectrum is distributed among different ethnicities (Table). The majority of individuals met clinical criteria for a polyposis syndrome, with 21 individuals reporting more than 99 adenomas (24.4%) and 50 individuals reporting 20-99 adenomas (58.1%). Conclusions: Analysis of only the two MYH FMs would miss 24% of biallelic individuals in our cohort. Due to the ethnicity distribution of mutations, it is difficult to predict who would be missed by this strategy. Consideration of MYH full sequencing is warranted to achieve highest clinical sensitivity. [Table: see text]

Antiplatelet therapy is routinely used in balloon angioplasty. Yet recent clinical trials have not shown these agents to reduce the incidence of restenosis. As this might be due to inadequate antiplatelet effect, this study was designed to evaluate the effectiveness of antiplatelet therapy in reducing platelet accumulation immediately after angioplasty. Sixty-six atherosclerotic rabbits underwent angioplasty of a focal (50-99%) iliac stenosis after pretreatment with an antiplatelet drug. The animals were randomly given aspirin (10 mg/kg orally) (n = 10), aspirin (10 mg/kg intravenously) (n = 7), aspirin (10 mg/kg per os) plus dipyridamole (25 mg orally) (n = 8), a thromboxane synthetase inhibitor (GS13080, 1 mg/kg/h intravenously) (n = 9) or heparin (500 U/kg intravenously) (n = 9). Platelet accumulation, determined by 51Cr-labeled platelet counts 30 min after angioplasty disclosed a significant reduction from control (44.1 +/- 51.2 platelets/cm x 10(6)) with intravenous aspirin (3.3 +/- 1.9; p less than 0.007) and the thromboxane synthetase inhibitor CGS13080 (15.1 +/- 16.6, p less than 0.04). Aspirin plus dipyridamole reduced platelet accumulation as well (10.4 +/- 9.8, p = 0.076), while oral aspirin (109.5 +/- 240) and heparin (34.7 +/- 35.5) were ineffective. The results of this study demonstrate that pretreatment with antiplatelet agents can reduce platelet accumulation significantly after experimental angioplasty. However, the wide variability in effectiveness particularly with oral aspirin may have important clinical implications. Further investigation into more effective antiplatelet therapy may help to reduce the incidence of abrupt vessel closure and restenosis.

11097 Background: Deleterious mutations in MLH1, MSH2 and MSH6 are known to cause Lynch Syndrome (HNPCC). The aim of this study was to determine the percentage of deleterious mutations represented ...

10513 Background: Mutations in the BRCA1 and BRCA2 genes are comprised of a majority of mutations that are detectable by sequence analysis, and a minority of large genomic deletion and duplication mutations that are detected by methods different than sequencing. Our laboratory developed and implemented a clinical assay for large rearrangements that we refer to as BART (BRCA1/2 Rearrangement Test). We validated the performance of BART using a completely anonymous large number of breast/ovarian cancer patient samples. We also demonstrated superior performance of BART versus other dosage-sensitive methods including Multiplex Ligation-dependent Probe Amplification (MLPA). Methods: BART utilizes quantitative endpoint polymerase chain reaction (PCR) in a multiplexed fluorescent format. Eleven multiplex PCR reactions were designed to contain two amplicons targeting the promoter region, all coding exons, and flanking regions of BRCA1 and BRCA2. An automated likelihood-based analysis application normalizes target amplicon copy number between BRCA1, BRCA2 and three control genes. Deletions and duplications are identified with a statistical confidence level. Results: Based on clinical and family history criteria, 1,035 patients were identified as severe-risk during the initial months of clinical BART analysis at Myriad Genetic Laboratories. All patients were initially tested for Comprehensive BRACAnalysis which includes BRCA1 and BRCA2 full gene sequencing plus large rearrangement panel testing for 5 recurrent BRCA1 mutations. Among severe-risk patients, 302 (29.2%) were positive for a BRCA1 or BRCA2 mutation by sequencing, 9 (0.9%) were positive by large rearrangement panel testing and an additional 27(2.6%) tested positive by BART for large genomic rearrangements. The total detection rate for deleterious mutations in severe-risk individuals was therefore 32.7%. Conclusions: Our initial clinical data indicate that BART testing is appropriate for high-risk patients identified on the basis of personal and family history criteria. No significant financial relationships to disclose.

We describe a laser-scanning two-photon fluorescence microscope that is capable of observing single molecules with excellent temporal resolution and three-dimensional spatial resolution. To demonstrate the capabilities of the instrument we present single-molecule fluorescence data obtained in several different scanning modes. In addition, a polarization-sensitive detection scheme can provide detailed three-dimensional information about the orientations of molecules in any of these scanning modes.