335 research outputs found
Intratumoral heterogeneity as a source of discordance in breast cancer biomarker classification
Abstract Background Spatial heterogeneity in biomarker expression may impact breast cancer classification. The aims of this study were to estimate the frequency of spatial heterogeneity in biomarker expression within tumors, to identify technical and biological factors contributing to spatial heterogeneity, and to examine the impact of discordant biomarker status within tumors on clinical record agreement. Methods Tissue microarrays (TMAs) were constructed using two to four cores (1.0Â mm) for each of 1085 invasive breast cancers from the Carolina Breast Cancer Study, which is part of the AMBER Consortium. Immunohistochemical staining for estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) was quantified using automated digital imaging analysis. The biomarker status for each core and for each case was assigned using clinical thresholds. Cases with core-to-core biomarker discordance were manually reviewed to distinguish intratumoral biomarker heterogeneity from misclassification of biomarker status by the automated algorithm. The impact of core-to-core biomarker discordance on case-level agreement between TMAs and the clinical record was evaluated. Results On the basis of automated analysis, discordant biomarker status between TMA cores occurred in 9Â %, 16Â %, and 18Â % of cases for ER, PR, and HER2, respectively. Misclassification of benign epithelium and/or ductal carcinoma in situ as invasive carcinoma by the automated algorithm was implicated in discordance among cores. However, manual review of discordant cases confirmed spatial heterogeneity as a source of discordant biomarker status between cores in 2Â %, 7Â %, and 8Â % of cases for ER, PR, and HER2, respectively. Overall, agreement between TMA and clinical record was high for ER (94Â %), PR (89Â %), and HER2 (88Â %), but it was reduced in cases with core-to-core discordance (agreement 70Â % for ER, 61Â % for PR, and 57Â % for HER2). Conclusions Intratumoral biomarker heterogeneity may impact breast cancer classification accuracy, with implications for clinical management. Both manually confirmed biomarker heterogeneity and misclassification of biomarker status by automated image analysis contribute to discordant biomarker status between TMA cores. Given that manually confirmed heterogeneity is uncommon (<10Â % of cases), large studies are needed to study the impact of heterogeneous biomarker expression on breast cancer classification and outcomes
Failing boys and moral panics: perspectives on the underachievement debate
The paper re-examines the underachievement debate from the perspective of the âdiscourse of derisionâ that surrounds much writing in this area. It considers the contradictions and inconsistencies which underpin much of the discourse â from a reinterpretation of examination scores, to the conflation of the concepts of âunderâ and âlowâ achievement and finally to the lack of consensus on a means of defining and measuring the term underachievement. In doing so, this paper suggests a more innovative approach for understanding, re-evaluating and perhaps rejecting the notion of underachievement
Grand Challenges in Global Health: Ethical, Social, and Cultural Issues Based on Key Informant Perspectives
The authors interviewed key informants from the developing world and the Grand Challenges investigators to explore their ethical, social, and cultural concerns about the program
The Mock LISA Data Challenges: from Challenge 3 to Challenge 4
The Mock LISA Data Challenges are a program to demonstrate LISA data-analysis
capabilities and to encourage their development. Each round of challenges
consists of one or more datasets containing simulated instrument noise and
gravitational waves from sources of undisclosed parameters. Participants
analyze the datasets and report best-fit solutions for the source parameters.
Here we present the results of the third challenge, issued in Apr 2008, which
demonstrated the positive recovery of signals from chirping Galactic binaries,
from spinning supermassive--black-hole binaries (with optimal SNRs between ~ 10
and 2000), from simultaneous extreme-mass-ratio inspirals (SNRs of 10-50), from
cosmic-string-cusp bursts (SNRs of 10-100), and from a relatively loud
isotropic background with Omega_gw(f) ~ 10^-11, slightly below the LISA
instrument noise.Comment: 12 pages, 2 figures, proceedings of the 8th Edoardo Amaldi Conference
on Gravitational Waves, New York, June 21-26, 200
PTF11eon/SN2011dh: Discovery of a Type IIb Supernova From a Compact Progenitor in the Nearby Galaxy M51
On May 31, 2011 UT a supernova (SN) exploded in the nearby galaxy M51 (the
Whirlpool Galaxy). We discovered this event using small telescopes equipped
with CCD cameras, as well as by the Palomar Transient Factory (PTF) survey, and
rapidly confirmed it to be a Type II supernova. Our early light curve and
spectroscopy indicates that PTF11eon resulted from the explosion of a
relatively compact progenitor star as evidenced by the rapid shock-breakout
cooling seen in the light curve, the relatively low temperature in early-time
spectra and the prompt appearance of low-ionization spectral features. The
spectra of PTF11eon are dominated by H lines out to day 10 after explosion, but
initial signs of He appear to be present. Assuming that He lines continue to
develop in the near future, this SN is likely a member of the cIIb (compact
IIb; Chevalier and Soderberg 2010) class, with progenitor radius larger than
that of SN 2008ax and smaller than the eIIb (extended IIb) SN 1993J progenitor.
Our data imply that the object identified in pre-explosion Hubble Space
Telescope images at the SN location is possibly a companion to the progenitor
or a blended source, and not the progenitor star itself, as its radius (~10^13
cm) would be highly inconsistent with constraints from our post-explosion
photometric and spectroscopic data
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Social, emotional, and behavioral functioning of secondary school students with low academic and language performance: perspectives from students, teachers, and parents
Adolescence is a time of transition when young people with language difficulties are at increased risk of experiencing social, emotional, and behavioral difficulties (SEBD). Most studies of social, emotional, and behavioral functioning (SEBF) in individuals with language difficulties focus on children with a clinical diagnosis of language impairment. This study explores SEBF in a nonclinical group of 12-year-old students with low educational and language performance from their own perspectives and those of their parents and teachers
Mutations in SLC25A22: hyperprolinaemia, vacuolated fibroblasts and presentation with developmental delay
Mutations in SLC25A22 are known to cause neonatal epileptic encephalopathy and migrating partial seizures in infancy. Using whole exome sequencing we identified four novel SLC25A22 mutations in six children from three families. Five patients presented clinical features similar to those in the literature including hypotonia, refractory neonatalâonset seizures and developmental delay. However, the sixth patients presented atypically with isolated developmental delay, developing lateâonset (absence) seizures only at 7 years of age. Abnormal metabolite levels have not been documented in the nine patients described previously. One patient in our series was referred to the metabolic clinic because of persistent hyperprolinaemia and another three had raised plasma proline when tested. Analysis of the postâprandial plasma amino acid response in one patient showed abnormally high concentrations of several amino acids. This suggested that, in the fed state, when amino acids are the preferred fuel for the liver, transâdeamination of amino acids requires transportation of glutamate into liver mitochondria by SLC25A22 for deamination by glutamate dehydrogenase; SLC25A22 is an important mitochondrial glutamate transporter in liver as well as in brain. Electron microscopy of patient fibroblasts demonstrated widespread vacuolation containing neutral and phosphoâlipids as demonstrated by Oil Red O and Sudan Black tinctorial staining; this might be explained by impaired activity of the proline/pyrrolineâ5âcarboxylate (P5C) shuttle if SLC25A22 transports pyrrolineâ5âcarboxylate/glutamateâÎłâsemialdehyde as well as glutamate
Consultations with complementary and alternative medicine practitioners amongst wider care options for back pain: a study of a nationally representative sample of 1,310 Australian women aged 60â65 years
Back pain is a significant health service issue in Australia and internationally. Back pain sufferers can draw upon a range of health care providers including complementary and alternative medicine (CAM) practitioners. Women are higher users of health services than men and tend to use CAM frequently for musculoskeletal conditions. However, there remain important gaps in our understanding of women's consultation patterns with CAM practitioners for back pain. The objective of this study is to examine the prevalence of use and characteristics of women who use CAM practitioners for back pain. The method used was a survey of a nationally representative sample of women aged 60-65 years from the Australian Longitudinal Study on Women's Health. Women consulted a massage therapist (44.1 %, n = 578) and a chiropractor (37.3 %, n = 488) more than other CAM practitioners for their back pain. Consultations with a chiropractor for back pain were lower for women who consulted a General Practitioner (GP) (OR, 0.56; 95 % CI 0.41, 0.76) or a physiotherapist (OR, 0.53; 95 % CI 0.39, 0.72) than for those who did not consult a GP or a physiotherapist. CAM practitioner consultations for back pain were greater for women who visited a pharmacist (OR, 1.99; 95 % CI 1.23, 3.32) than for women who did not visit a pharmacist. There is substantial use of CAM practitioners alongside conventional practitioners amongst women for back pain, and there is a need to provide detailed examination of the communication between patients and their providers as well as across the diverse range of health professionals involved in back pain care
Clostridium difficile 027 infection in Central Italy
Background
Clostridium difficile (CD) has increasingly become recognised as a significant international health burden, often associated with the healthcare environment. The upsurge in incidence of CD coincided with the emergence of a hypervirulent strain of CD characterized as 027.
In 2010, 8 cases of CD 027 infections were identified in Italy. Since then, no further reports have been published. We describe 10 new cases of CD 027 infection occurring in Italy.
Methods
Since December 2010, stool samples of patients with severe diarrhea and clinical suspicion of the presence of a hypervirulent strain, were tested for CD 027 by the Xpert C. difficile PCR assay (Cepheid, Sunnyvale, CA). Clinical, epidemiological and laboratory data were collected.
Results
From December 2010 to April 2012, 24 faecal samples from 19 patients who fit the above criteria were submitted to our laboratory. Samples were collected from 7 different hospitals.
Of these, 17 had a positive PCR for CD and 10 were the epidemic 027 strain (59%). All PCR positive samples had a positive EIA toxin A/B test. Nine of 10 patients were recently exposed to antimicrobials and were healthcare-associated, including 4 with a history of long term care facility (LTCF) admission; the remaining case was community-associated, namely the wife of a patient with hospital-acquired CD 027 infection. Five patients experienced at least one recurrence of CD associated diarrhea (CDAD) with a total of 12 relapsing episodes. Of these, two patients had 5 and 6 relapses respectively.
We compared the 10 patients with 027 CDAD versus the 7 patients with non-027 CDAD. None of the 7 patients with non-027 CDAD had a recent history of LTCF admission and no subsequent relapses were observed (pâ=â0.04).
Conclusions
Our study shows that CD 027 is emerging in healthcare facilities in Italy. Whilst nosocomial acquisition accounted for the majority of such cases, 4 patients had history of a recent stay in a LTCF. We highlight the substantial risks of this highly transmissible organism in such environments. Moreover, 50% of our patients with CDAD from the 027 strain had high relapse rates which may serve to further establish this strain within the Italian health and social care systems
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