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Find video protocols related to scientific articles indexed in Pubmed.
Assessment of Student Interprofessional Education (IPE) Training for Team-Based Geriatric Home Care: Does IPE Training Change Students Knowledge and Attitudes?
Home Health Care Serv Q
PUBLISHED: 09-27-2014
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ABSTRACT Our study assesses changes in student's knowledge and attitudes after participation in an interprofessional, team based, geriatric home training program. Second-year medical, physician assistant, occupational therapy, social work, and physical therapy students, third-year pharmacy students, and fourth-year dental students were led by interprofessional faculty teams. Student participants were assessed before and after the curriculum using an interprofessional attitudes learning scale. Significant differences and positive data trends were noted at year-end. Our study suggests that early implementation, assessment, and standardization of years of student training is needed for optimal interprofessional geriatric learning. Additionally, alternative student assessment tools should be considered for future studies.
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PedVacc 002: a phase I/II randomized clinical trial of MVA.HIVA vaccine administered to infants born to human immunodeficiency virus type 1-positive mothers in Nairobi.
Vaccine
PUBLISHED: 08-27-2014
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A safe, effective vaccine for breastfeeding infants born to HIV-1-positive mothers could complement antiretroviral therapy (ART) for prevention of mother-to-child transmission of HIV-1. To date, only a few HIV-1 vaccine candidates have been tested in infants.
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Stochastic specification of primordial germ cells from mesoderm precursors in axolotl embryos.
Development
PUBLISHED: 06-12-2014
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A common feature of development in most vertebrate models is the early segregation of the germ line from the soma. For example, in Xenopus and zebrafish embryos primordial germ cells (PGCs) are specified by germ plasm that is inherited from the egg; in mice, Blimp1 expression in the epiblast mediates the commitment of cells to the germ line. How these disparate mechanisms of PGC specification evolved is unknown. Here, in order to identify the ancestral mechanism of PGC specification in vertebrates, we studied PGC specification in embryos from the axolotl (Mexican salamander), a model for the tetrapod ancestor. In the axolotl, PGCs develop within mesoderm, and classic studies have reported their induction from primitive ectoderm (animal cap). We used an axolotl animal cap system to demonstrate that signalling through FGF and BMP4 induces PGCs. The role of FGF was then confirmed in vivo. We also showed PGC induction by Brachyury, in the presence of BMP4. These conditions induced pluripotent mesodermal precursors that give rise to a variety of somatic cell types, in addition to PGCs. Irreversible restriction of the germ line did not occur until the mid-tailbud stage, days after the somatic germ layers are established. Before this, germline potential was maintained by MAP kinase signalling. We propose that this stochastic mechanism of PGC specification, from mesodermal precursors, is conserved in vertebrates.
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Analysis of incidence and prognosis from 'extreme' case-control designs.
Stat Med
PUBLISHED: 05-21-2014
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The significant investment in measuring biomarkers has prompted investigators to improve cost-efficiency by sub-sampling in non-standard study designs. For example, investigators studying prognosis may assume that any differences in biomarkers are likely to be most apparent in an extreme sample of the earliest deaths and the longest-surviving controls. Simple logistic regression analysis of such data does not exploit the information available in the survival time, and statistical methods that model the sampling scheme may be more efficient. We derive likelihood equations that reflect the complex sampling scheme in unmatched and matched 'extreme' case-control designs. We investigated the performance and power of the method in simulation experiments, with a range of underlying hazard ratios and study sizes. Our proposed method resulted in hazard ratio estimates close to those obtained from the full cohort. The standard error estimates also performed well when compared with the empirical variance. In an application to a study investigating markers for lethal prostate cancer, an extreme case-control sample of lethal cases and the longest-surviving controls provided estimates of the effect of Gleason score in close agreement with analysis of all the data. By using the information in the sampling design, our method enables efficient and valid estimation of the underlying hazard ratio from a study design that is intuitive and easily implemented. Copyright © 2014 John Wiley & Sons, Ltd.
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Associations of Rhesus and non-Rhesus maternal red blood cell alloimmunization with stillbirth and preterm birth.
Int J Epidemiol
PUBLISHED: 05-05-2014
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Although the risks of adverse pregnancy outcomes associated with anti-D antibodies are well-recognized, much less is known concerning alloimmunization with other red blood cell antibodies detected during routine maternal screening. To date, most reports of adverse pregnancy outcomes associated with non-anti-D antibodies have been from small case studies. The aim of this study was to examine the associations of maternal alloimmunization with specific red blood cell antibodies and the risks of preterm birth and stillbirth in the Swedish population.
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Patterns of changing cancer risks with time since diagnosis of a sibling.
Int. J. Cancer
PUBLISHED: 04-04-2014
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Family history is a well-known risk factor for many cancers. However, it is important to know if/how the familial risk of cancer changes over time. For each of four major cancers (colorectal, breast, prostate and melanoma), we identified siblings of cancer patients (case siblings) and siblings of matched cancer-free controls sampled from Swedish population-based registers. Effects of age and time since diagnosis on sibling risks were examined using Poisson regression and presented graphically as smoothed hazard ratios (HRs). Screening effects were investigated by comparing hazards before/after the introduction of mammography for breast cancer and prostate-specific antigen (PSA) testing for prostate cancer. Case siblings had higher cancer incidence than control siblings for all cancers at all ages, with overall incidence rate ratios (IRRs) of 2.41 (95% confidence interval 2.14-2.71) for colorectal cancer, 2.37 (2.24-2.52) for breast cancer, 3.69 (3.46-3.93) for prostate cancer and 3.20 (2.72-3.76) for melanoma. Risks were highest in siblings who were young when the first cancer was diagnosed in the family, with siblings aged 30-40 having IRR 9.05 (3.03-27.00) for colorectal cancer and 4.30 (2.87-6.45) for breast cancer. Smoothed HRs remained fairly constant for up to 20 years except for prostate cancer, where the HR decreased steeply during the first few years. After introduction of PSA testing, men had higher incidence of prostate cancer shortly after diagnosis in a brother, but no such screening effect was found for breast cancer. Our findings can help inform the screening and counseling of family members of cancer patients.
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A maximum likelihood method for secondary analysis of nested case-control data.
Stat Med
PUBLISHED: 01-13-2014
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Many epidemiological studies use a nested case-control (NCC) design to reduce cost while maintaining study power. Because NCC sampling is conditional on the primary outcome, routine application of logistic regression to analyze a secondary outcome will generally be biased. Recently, many studies have proposed several methods to obtain unbiased estimates of risk for a secondary outcome from NCC data. Two common features of all current methods requires that the times of onset of the secondary outcome are known for cohort members not selected into the NCC study and the hazards of the two outcomes are conditionally independent given the available covariates. This last assumption will not be plausible when the individual frailty of study subjects is not captured by the measured covariates. We provide a maximum-likelihood method that explicitly models the individual frailties and also avoids the need to have access to the full cohort data. We derive the likelihood contribution by respecting the original sampling procedure with respect to the primary outcome. We use proportional hazard models for the individual hazards, and Clayton's copula is used to model additional dependence between primary and secondary outcomes beyond that explained by the measured risk factors. We show that the proposed method is more efficient than weighted likelihood and is unbiased in the presence of shared frailty for the primary and secondary outcome. We illustrate the method with an application to a study of risk factors for diabetes in a Swedish cohort.
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A unified model for estimating and testing familial aggregation.
Stat Med
PUBLISHED: 09-24-2013
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Investigations of familial aggregation of disease can provide important clues for genetic mechanisms, and many such studies have been published in the epidemiological literature using various statistical methods. We developed a unified model for familial risk by extending a Cox regression model to enable estimation of the detailed effects of kinship. By appropriate parameterisation of the model, we show how the risks to all specific first-degree kinships can be estimated and formally compared using simple interaction terms and how the model can be extended to accommodate higher-degree relatives. The correlation due to observations from family members and from the potential for repeated observations is accommodated by a robust sandwich variance estimator or a bootstrap estimate. Hazard ratios for different kinships are formally compared using a robust Wald test. We illustrate the method with applications to studies of adult leukemia and non-Hodgkins lymphoma in the Swedish population and display our results on a pedigree diagram. Our estimates are consistent with published work that used simpler stratified methods, and our model enabled the detection of a number of statistically significant effects of kinship. The recognition of such kindred-specific disease risk could be a first step in the design of more informative genetic biomarker studies. Copyright © 2013 John Wiley & Sons, Ltd.
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Multilocus genetic risk scores for coronary heart disease prediction.
Arterioscler. Thromb. Vasc. Biol.
PUBLISHED: 05-16-2013
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Current guidelines do not support the use of genetic profiles in risk assessment of coronary heart disease (CHD). However, new single nucleotide polymorphisms associated with CHD and intermediate cardiovascular traits have recently been discovered. We aimed to compare several multilocus genetic risk score (MGRS) in terms of association with CHD and to evaluate clinical use.
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Validation, calibration and refitting of a familial breast cancer model in sisterships: a case study in the Swedish sisters data.
Stat Med
PUBLISHED: 01-31-2013
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In Sweden, a unique data set has been compiled with breast cancer incidence in all sisterships with at least two sisters born between 1932 and 2001, and the effect of family history has been analyzed by standard epidemiological methods. Such data are ideal to explore the validity of existing models for familial breast cancer. This paper explores the validity of the Jonker model that adds a hypothetical gene to the well-known BRCA1 and BRCA2 genes. The validity of the model for the Swedish data is checked by using a calibration model for breast cancer incidence given the (retrospective) family history as assessed at the end of the study period. This enables the validity of the overall incidence and the effect of family history to be assessed in the same model. The conclusion is that the existing model does reasonably well for the effect of family history but is seriously wrong for the early incidence rate. Therefore, the model is refitted in the Swedish data. Finally, the calibration of the refitted model is checked when using current family history as used in the epidemiological studies. The refitted Jonker model fits the data well and shows good agreement with the epidemiological findings.
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A Phase I Randomized Clinical Trial of Candidate Human Immunodeficiency Virus type 1 Vaccine MVA.HIVA Administered to Gambian Infants.
PLoS ONE
PUBLISHED: 01-01-2013
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A vaccine to decrease transmission of human immunodeficiency virus type 1 (HIV-1) during breast-feeding would complement efforts to eliminate infant HIV-1 infection by antiretroviral therapy. Relative to adults, infants have distinct immune development, potentially high-risk of transmission when exposed to HIV-1 and rapid progression to AIDS when infected. To date, there have been only three published HIV-1 vaccine trials in infants.
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Constructing a population-based research database from routine maternal screening records: a resource for studying alloimmunization in pregnant women.
PLoS ONE
PUBLISHED: 10-20-2011
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Although screening for maternal red blood cell antibodies during pregnancy is a standard procedure, the prevalence and clinical consequences of non-anti-D immunization are poorly understood. The objective was to create a national database of maternal antibody screening results that can be linked with population health registers to create a research resource for investigating these issues.
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Phenotypic characterization of HIV-specific CD8+ T cells during early and chronic infant HIV-1 infection.
PLoS ONE
PUBLISHED: 02-21-2011
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Although CD8(+) T cells play an important role in the containment of adult HIV-1 replication, their role in infant HIV-1 infection is not as well understood. Impaired HIV-specific CD8(+) T cell responses may underlie the persistently high viral loads observed in infants. We examined the frequency and phenotype of infant HIV-specific CD8(+) T cells in 7 HIV-infected antiretroviral therapy-naïve infants during the first 2 years of life, using class I HLA tetramers and IFN-?-ELISPOT. The frequency (0.088-3.9% of CD3(+)CD8(+) cells) and phenotype (CD27(+)CD28(-), CD45RA(+/-), CD57(+/-), HLA-DR(+), CD95(+)) of infant HIV-specific CD8(+) T cells were similar to reports in adults undergoing early infection. Unlike adults, at 23-24 months post-infection a high frequency of HIV-specific CD8(+) T cells expressed HLA-DR (mean 80%, range 68-85%) and CD95 (mean 88%, range 79-96%), suggesting sustained activation and vulnerability to apoptosis. Despite comparable expansion of HIV-specific CD8(+) T cells of a similar phenotype to adults during early infection, infant T cells failed to contain HIV-1 replication, and remained persistently activated and vulnerable to apoptosis during chronic infection.
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Are chronic myeloid leukemia patients more at risk for second malignancies? A population-based study.
Am. J. Epidemiol.
PUBLISHED: 09-22-2010
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The authors used cancer registry data to assess the incidence rate of second primary cancers among chronic myeloid leukemia (CML) patients and the long-term survival of CML patients before the introduction of tyrosine kinase inhibitors. In the Swedish Cancer Registry, the authors identified 2,753 adult CML patients diagnosed between 1970 and 1995 who were followed through December 2007. Standardized incidence ratios (SIRs) and relative survival ratios were computed. With a total of 145 subsequent primary malignancies, an increased incidence rate of second malignancy was found for stomach cancer (SIR = 2.76, 95% confidence interval (CI): 1.33, 5.08), skin cancer (SIR = 5.36, 95% CI: 3.18, 8.47), urogenital tract cancer (SIR = 1.61, 95% CI: 1.15, 2.21), and lymphoid leukemia (SIR = 5.53, 95% CI: 1.79, 12.89). Long-term relative survival figures showed that CML was related, in the era prior to the introduction of imatinib, to a very steep decline in survival (2 years from diagnosis, relative survival = 51%, 95% CI: 49, 53). This was in spite of a marginal improvement after 1985, possibly related to the introduction of interferon-? for treatment. These estimates constitute a relevant reference for future studies and a benchmark for comparisons with prognosis in CML patients after chronic use of tyrosine kinase inhibitors.
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Responses to a modified visual cliff by pre-walking infants born preterm and at term.
Phys Occup Ther Pediatr
PUBLISHED: 02-23-2010
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The purpose of this study was to examine, using a modified visual cliff apparatus, possible perceptual differences at crawling age between infants born preterm and infants born at term without documented visual or motor impairments. Sixteen infants born at term and 16 born preterm were encouraged to crawl to their caregivers on a modified visual cliff. Successful trials, crossing time, duration of visual attention, duration of tactile exploration, motor strategies, and avoidance behaviors were analyzed. A significant surface effect was found, with longer crossing times and longer durations of visual attention and tactile exploration in the condition with the visual appearance of a deep cliff. Although the two groups of infants did not differ on any of the timed measures, infants born at term demonstrated a larger number of motor strategies and avoidance behaviors by simple tally. This study indicates that infants born at term and those born preterm can perceive a visual cliff and adapt their responses accordingly.
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Duration of red blood cell storage and survival of transfused patients (CME).
Transfusion
PUBLISHED: 02-12-2010
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Disquieting reports of increased complication and death rates after transfusions of red blood cells (RBCs) stored for more than 14 days prompted us to perform an observational retrospective cohort study of mortality in relation to storage time.
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Should plasma from female donors be avoided? A population-based cohort study of plasma recipients in Sweden from 1990 through 2002.
Transfusion
PUBLISHED: 01-22-2010
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Plasma from female donors has been implicated in the sometimes fatal complication known as transfusion-related acute lung injury. In studies of patients in intensive care units, worsened gas exchange of the lungs has also been attributed to female plasma. Despite a lack of population-based evidence, policies have already been introduced to exclude female donor plasma.
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The relationship between a statewide preceptorship program and family medicine residency selection.
J Am Board Fam Med
PUBLISHED: 01-07-2010
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The purpose of this study was to investigate the extent to which participation in the California Academy of Family Physicians Foundation Family Medicine (FM) Preceptorship Program, as well as medical school, degree earned, gender, and match year predicted FM residency match.
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Matched ascertainment of informative families for complex genetic modelling.
Behav. Genet.
PUBLISHED: 11-28-2009
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Family data are used extensively in quantitative genetic studies to disentangle the genetic and environmental contributions to various diseases. Many family studies based their analysis on population-based registers containing a large number of individuals composed of small family units. For binary trait analyses, exact marginal likelihood is a common approach, but, due to the computational demand of the enormous data sets, it allows only a limited number of effects in the model. This makes it particularly difficult to perform joint estimation of variance components for a binary trait and the potential confounders. We have developed a data-reduction method of ascertaining informative families from population-based family registers. We propose a scheme where the ascertained families match the full cohort with respect to some relevant statistics, such as the risk to relatives of an affected individual. The ascertainment-adjusted analysis, which we implement using a pseudo-likelihood approach, is shown to be efficient relative to the analysis of the whole cohort and robust to mis-specification of the random effect distribution.
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Peptide microarray-based identification of Mycobacterium tuberculosis epitope binding to HLA-DRB1*0101, DRB1*1501, and DRB1*0401.
Clin. Vaccine Immunol.
PUBLISHED: 10-28-2009
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A more effective vaccine against Mycobacterium tuberculosis is needed, and a number of M. tuberculosis vaccine candidates are currently in preclinical or clinical phase I and II studies. One of the strategies to select M. tuberculosis (protein) targets to elicit a CD8(+) or CD4(+) T-cell response is to gauge the binding of candidate peptides to major histocompatibility complex (MHC) class I or class II molecules, a prerequisite for successful peptide presentation and to expand antigen-specific T cells. We scanned 61 proteins from the M. tuberculosis proteome for potential MHC class II-presented epitopes that could serve as targets for CD4(+) T-cell responses. We constructed a peptide microarray consisting of 7,466 unique peptides derived from 61 M. tuberculosis proteins. The peptides were 15-mers overlapping by 12 amino acids. Soluble recombinant DRB1*0101 (DR1), DRB1*1501 (DR2), and DRB1*0401 (DR4) monomers were used to gauge binding to individual peptide species. Out of 7,466 peptides, 1,282, 674, and 1,854 peptides formed stable complexes with HLA-DR1, -DR2, and -DR4, respectively. Five hundred forty-four peptides bound to all three MHC class II molecules, 609 bound to only two, and 756 bound to only a single MHC class II molecule. This allowed us to rank M. tuberculosis proteins by epitope density. M. tuberculosis proteins contained "hot spots," i.e., regions with enriched MHC class II binding epitopes. Two hundred twenty-two peptides that formed MHC class II-peptide complexes had previously been described as exclusively recognized by IgG in sera from patients with active pulmonary tuberculosis, but not in sera from healthy individuals, suggesting that these peptides serve as B-cell and CD4(+) T-cell epitopes. This work helps to identify not only M. tuberculosis peptides with immunogenic potential, but also the most immunogenic proteins. This information is useful for vaccine design and the development of future tools to explore immune responses to M. tuberculosis.
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Maternal effects for preterm birth: a genetic epidemiologic study of 630,000 families.
Am. J. Epidemiol.
PUBLISHED: 10-23-2009
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This study was undertaken to disentangle the maternal genetic from the fetal genetic effects for preterm birth and to study the possibility of these effects being explained by known risk factors. By cross-linking of the population-based Swedish Multigeneration and Medical Birth registers, 989,027 births between 1992 and 2004 were identified. Alternating logistic regression was applied to model the familial clustering with pairwise odds ratios (PORs), and covariates were included to evaluate if the familial aggregation was explained by exposure to shared risk factors. Generalized linear mixed models were used to estimate the contribution of genetic and environmental effects. Sisters of women who had a preterm delivery had themselves an increased odds of having a preterm delivery (POR = 1.8, 95% confidence interval: 1.5, 2.1), while there was no corresponding increase in odds in families joined by brothers (POR = 1.1, 95% confidence interval: 0.9, 1.4). Twenty-five percent of the variation in preterm birth was explained by maternal genetic factors, whereas fetal genetic factors only marginally influenced the variation in liability. The increased odds ratio between offspring of sisters was independent of maternal risk factors for preterm birth, suggesting that the relative importance of maternal effects is not explained by these well-known risk factors.
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Bias correction of estimates of familial risk from population-based cohort studies.
Int J Epidemiol
PUBLISHED: 10-13-2009
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In addition to guiding molecular epidemiology investigations, estimates of the increased risk of disease in relatives of affected persons are also important for screening and counselling decisions. Since precise estimation of such familial risks (FRs) requires large sample sizes, many of the estimates in common use have been obtained from historical electronic records of disease in entire populations, where the relatives of affected and unaffected persons are compared. These estimates may be biased due to failure to identify relatives as affected if they are diagnosed before the start-up date of disease registration.
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Shaping professionalism in pre-clinical medical students: Professionalism and the practice of medicine.
Med Teach
PUBLISHED: 10-09-2009
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Increasing emphasis is placed on teaching and assessment of professionalism in the continuum of medical education. Consistent and longitudinal instruction and assessment are crucial factors that learners need in order to internalize the tenets of professionalism.
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Expensive blood safety initiatives may offer less benefit than we think.
Transfusion
PUBLISHED: 09-16-2009
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Various blood safety initiatives have ensured a historically low risk of infection transmission through blood transfusion. Although further prevention of infection transmission is possible through, for example, nucleic acid testing and future introduction of pathogen inactivation, such initiatives are very costly in relation to the benefit they offer. Although estimation of the cost-effectiveness requires detailed information about the survival of transfusion recipients, previous cost-effectiveness analyses have relied on incorrect survival assumptions.
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Visualisation and pre-processing of peptide microarray data.
Methods Mol. Biol.
PUBLISHED: 08-04-2009
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The data files produced by digitising peptide microarray images contain detailed information on the location, feature, response parameters and quality of each spot on each array. In this chapter, we will describe how such peptide microarray data can be read into the R statistical package and pre-processed in preparation for subsequent comparative or predictive analysis. We illustrate how the information in the data can be visualised using images and graphical displays that highlight the main features, enabling the quality of the data to be assessed and invalid data points to be identified and excluded. The log-ratio of the foreground to background signal is used as a response index. Negative control responses serve as a reference against which "detectable" responses can be defined, and slides incubated with only buffer and secondary antibody help identify false-positive responses from peptides. For peptides that have a detectable response on at least one subarray, and no false-positive response, we use linear mixed models to remove artefacts due to the arrays and their architecture. The resulting normalized responses provide the input data for further analysis.
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Improved salt iodation methods for small-scale salt producers in low-resource settings in Tanzania.
BMC Public Health
PUBLISHED: 06-17-2009
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Universal salt iodation will prevent iodine deficiency disorders (IDD). Globally, salt-iodation technologies mostly target large and medium-scale salt-producers. Since most producers in low-income countries are small-scale, we examined and improved the performance of hand and knapsack-sprayers used locally in Tanzania.
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A constant risk for familial breast cancer? A population-based family study.
Breast Cancer Res.
PUBLISHED: 04-21-2009
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The incidence of breast cancer in the unaffected breast of women with previous breast malignancy remains constant after the first diagnosis. We investigated whether there is a similar pattern in the breast cancer incidence in first-degree relatives of breast cancer patients. We studied the risk for breast cancer in mothers at ages older than their daughters age at diagnosis.
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Combining data from 2 nested case-control studies of overlapping cohorts to improve efficiency.
Biostatistics
PUBLISHED: 02-20-2009
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Researchers subject to time and budget constraints may conduct small nested case-control studies with individually matched controls to help optimize statistical power. In this paper, we show how precision can be improved considerably by combining data from a small nested case-control study with data from a larger nested case-control study of a different outcome in the same or overlapping cohort. Our approach is based on the inverse probability weighting concept, in which the log-likelihood contribution of each individual observation is weighted by the inverse of its probability of inclusion in either study. We illustrate our approach using simulated data and an application where we combine data sets from 2 nested case-control studies to investigate risk factors for anorexia nervosa in a cohort of young women in Sweden.
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Major histocompatibility complex class II molecule-human immunodeficiency virus peptide analysis using a microarray chip.
Clin. Vaccine Immunol.
PUBLISHED: 02-18-2009
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Identification of major histocompatibility complex (MHC) class II binding peptides is a crucial step in rational vaccine design and immune monitoring. We designed a novel MHC class II molecule-peptide microarray binding assay and evaluated 346 peptides from already identified human immunodeficiency virus (HIV) epitopes and an additional set (n = 206) of 20-mer peptides, overlapping by 15 amino acid residues, from HIV type 1B (HIV-1B) gp160 and Nef as a paradigm. Peptides were attached via the N-terminal part to a linker that covalently binds to the epoxy glass slide. The 552 peptides were printed in triplicate on a single peptide microarray chip and tested for stable formation of MHC class II molecule-peptide complexes using recombinant soluble DRB1*0101(DR1), DRB1*1501(DR2), and DRB1*0401(DR4) molecules. Cluster analysis revealed unique patterns of peptide binding to all three, two, or a single MHC class II molecule. MHC class II binding peptides reside within previously described immunogenic regions of HIV gp160 and Nef, yet we could also identify new MHC class II binding peptides from gp160 and Nef. Peptide microarray chips allow the comprehensive and simultaneous screening of a high number of candidate peptide epitopes for MHC class II binding, guided by subsequent quality data extraction and binding pattern cluster analysis.
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Blood transfusion exposure in Denmark and Sweden.
Transfusion
PUBLISHED: 02-06-2009
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Although essential for the evaluation of blood transfusion safety, the prevalence of blood transfusion in the general population is not presently known. This study estimated the exposure to blood transfusion in the general Scandinavian population.
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Identification and testing of control peptides for antigen microarrays.
J. Immunol. Methods
PUBLISHED: 01-20-2009
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Peptide microarray slides usually contain positive control spots to gauge for antibody binding. Unlike the good response on earlier prototype microarrays, human immunoglobulin controls do not function consistently on newer generation slides. This may be due to technical problems in high-density printing or degradation. Our objective was to identify and print reliable control peptides that did not suffer from the same problems as proteins.
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An ecological model for family violence prevention across the life cycle.
Fam Med
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Family violence (FV) impacts individuals and their families, their communities, their physical health, and the economic health of society. The origins of FV are complex, and relationships among historical, cultural, interpersonal, and intrapersonal components are poorly understood. The morbidity, mortality, and cost of FV are enormous. This paper introduces an ecological model for FV prevention through the life cycle-from child abuse through interpersonal violence and to elder abuse. The model incorporates medical as well as social, justice, and educational literature about violence prevention efforts and programs. Health care professionals, particularly in family medicine, are on the front line of preventing family violence. The responsibilities and competencies related to preventing/addressing family violence include (1) identifying risk factors, (2) noting early signs and symptoms, (3) assessing for violence within families, (4) managing sequelae to minimize morbidity and mortality, (5) knowing/using referral and community resources, and (6) advocating for changes that promote a violence-free society. The model presented in this article provides a holistic approach to FV. This model can be applied to the Patient-centered Medical Home to promote educational initiatives, inter-professional collaborations, and community and population-based efforts to prevent and to decrease violence.
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Acute cytomegalovirus infection is associated with increased frequencies of activated and apoptosis-vulnerable T cells in HIV-1-infected infants.
J. Virol.
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Cytomegalovirus (CMV) coinfection is associated with infant HIV-1 disease progression and mortality. In a cohort of Kenyan HIV-infected infants, the frequencies of activated (CD38(+) HLA-DR(+)) and apoptosis-vulnerable (CD95(+) Bcl-2(-)) CD4(+) and CD8(+) T cells increased substantially during acute CMV infection. The frequency of activated CD4(+) T cells was strongly associated with both concurrent CMV coinfection (P = 0.001) and HIV-1 viral load (P = 0.05). The frequency of apoptosis-vulnerable cells was also associated with CMV coinfection in the CD4 (P = 0.02) and CD8 (P < 0.001) T cell subsets. Similar observations were made in HIV-exposed uninfected infants. CMV-induced increases in T cell activation and apoptosis may contribute to the rapid disease progression in coinfected infants.
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Noninvasive single-exon fetal RHD determination in a routine screening program in early pregnancy.
Obstet Gynecol
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To develop a simple and robust assay suitable for fetal RHD screening in first-trimester pregnancy and to estimate the sensitivity and specificity of the test after its implementation in an unselected pregnant population.
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The impact of plasma preparations and their storage time on short-term posttransfusion mortality: a population-based study using the Scandinavian Donation and Transfusion database.
J Trauma Acute Care Surg
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The treatment of coagulopathy and bleeding in severe trauma requires rapid delivery of large amounts of plasma to emergency wards. The resulting need for adequate supplies of nonfrozen or thawed plasma has consequences for storage strategies. Using extensive population data from a setting where both fresh-frozen plasma (FFP) and cold-stored liquid plasma were used, this study investigates whether there is an association between short-term mortality after receipt of FFP or liquid plasma of different storage times.
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Risk prediction measures for case-cohort and nested case-control designs: an application to cardiovascular disease.
Am. J. Epidemiol.
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Case-cohort and nested case-control designs are often used to select an appropriate subsample of individuals from prospective cohort studies. Despite the great attention that has been given to the calculation of association estimators, no formal methods have been described for estimating risk prediction measures from these 2 sampling designs. Using real data from the Swedish Twin Registry (2004-2009), the authors sampled unstratified and stratified (matched) case-cohort and nested case-control subsamples and compared them with the full cohort (as "gold standard"). The real biomarker (high density lipoprotein cholesterol) and simulated biomarkers (BIO1 and BIO2) were studied in terms of association with cardiovascular disease, individual risk of cardiovascular disease at 3 years, and main prediction metrics. Overall, stratification improved efficiency, with stratified case-cohort designs being comparable to matched nested case-control designs. Individual risks and prediction measures calculated by using case-cohort and nested case-control designs after appropriate reweighting could be assessed with good efficiency, except for the finely matched nested case-control design, where matching variables could not be included in the individual risk estimation. In conclusion, the authors have shown that case-cohort and nested case-control designs can be used in settings where the research aim is to evaluate the prediction ability of new markers and that matching strategies for nested case-control designs may lead to biased prediction measures.
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The value of reusing prior nested case-control data in new studies with different outcome.
Stat Med
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Many epidemiological studies use a nested case-control (NCC) design to reduce cost while maintaining study power. However, because of the incidence density sampling used, reusing data from NCC studies for analysis of secondary outcomes is not straightforward. Recent methodological developments have opened the possibility for prior NCC data to be used to complement controls in a current study, thereby improving study efficiency. However, practical guidelines on the effectiveness of prior data relative to newly sampled subjects and the potential power gains are still lacking. Using simulated cohorts, we show in this paper how the efficiency of NCC studies that use a mixture of prior and newly sampled subjects depends on the number of newly sampled controls and prior subjects as well as the overlap in the distributions of the matching variables. We explore the feasibility and efficiency of a current study that gathers no controls, relying instead on prior data. Using the concept of effective number of controls, we show how researchers can assess the potential power gains from reusing prior data. We apply the method to analyses of anorexia and contralateral breast cancer in the Swedish population and show how power calculations can be done using publicly available software. This work has important applications in genetic and molecular epidemiology to make optimal use of costly exposure measurements.
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JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

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In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.