Dengue virus-infected human dendritic cells reveal hierarchies of naturally expressed novel NS3 CD8 T cell epitopes

Detailed knowledge of dengue virus (DENV) cell-mediated immunity is limited. In this study we characterize CD8(+) T lymphocytes recognizing three novel and two known non-structural protein 3 peptide epitopes in DENV-infected dendritic cells. Three epitopes displayed high conservation (75-100%), compared to the others (0-50%). A hierarchy ranking based on magnitude and polyfunctionality of the antigen-specific response showed that dominant epitopes were both highly conserved and cross-reactive against multiple DENV serotypes. These results are relevant to DENV pathogenesis and vaccine design.

Molecular classifiers for acute kidney transplant rejection in peripheral blood by whole genome gene expression profiling

There are no minimally invasive diagnostic metrics for acute kidney transplant rejection (AR), especially in the setting of the common confounding diagnosis, acute dysfunction with no rejection (ADNR). Thus, though kidney transplant biopsies remain the gold standard, they are invasive, have substantial risks, sampling error issues and significant costs and are not suitable for serial monitoring. Global gene expression profiles of 148 peripheral blood samples from transplant patients with excellent function and normal histology (TX; n = 46), AR (n = 63) and ADNR (n = 39), from two independent cohorts were analyzed with DNA microarrays. We applied a new normalization tool, frozen robust multi-array analysis, particularly suitable for clinical diagnostics, multiple prediction tools to discover, refine and validate robust molecular classifiers and we tested a novel one-by-one analysis strategy to model the real clinical application of this test. Multiple three-way classifier tools identified 200 highest value probesets with sensitivity, specificity, positive predictive value, negative predictive value and area under the curve for the validation cohort ranging from 82% to 100%, 76% to 95%, 76% to 95%, 79% to 100%, 84% to 100% and 0.817 to 0.968, respectively. We conclude that peripheral blood gene expression profiling can be used as a minimally invasive tool to accurately reveal TX, AR and ADNR in the setting of acute kidney transplant dysfunction.

Cozen's phenomenon: a reminder

A four-year-old child attended Accident and Emergency following a fall from a slide with a displaced and angulated proximal tibial metaphyseal fracture. Treatment included closed manipulation under anaesthesia and an above knee cast for seven weeks. Serial radiographs over the following few months were satisfactory demonstrating good alignment and evidence of healing. However, at four-months review new-onset genu valgum with mechanical axis deviation was noted. No evidence of spontaneous resolution was noted over the following 12 months and hence a corrective hemi-epiphysiodesis was performed. At 12-months post-operatively, there was marked clinical and radiographical improvement in alignment. Classically Cozen's phenomenon is described as the late-onset post-traumatic valgus deformity associated with proximal tibial metaphyseal fractures in children. We want to reemphasise the early recognition of children at risk of this unique complication. In addition, we wish to highlight the progression of the late-onset valgus and its subsequent management.

Transforming rural health systems through clinical academic leadership: lessons from South Africa

CONTEXT

Under-resourced and poorly managed rural health systems challenge the achievement of universal health coverage, and require innovative strategies worldwide to attract healthcare staff to rural areas. One such strategy is rural health training programs for health professionals. In addition, clinical leadership (for all categories of health professional) is a recognised prerequisite for substantial improvements in the quality of care in rural settings.

ISSUE

Rural health training programs have been slow to develop in low- and middle-income countries (LMICs); and the impact of clinical leadership is under-researched in such settings. A 2012 conference in South Africa, with expert input from South Africa, Canada and Australia, discussed these issues and produced recommendations for change that will also be relevant in other LMICs. The two underpinning principles were that: rural clinical leadership (both academic and non-academic) is essential to developing and expanding rural training programs and improving care in LMICs; and leadership can be learned and should be taught.

LESSONS LEARNED

The three main sets of recommendations focused on supporting local rural clinical academic leaders; training health professionals for leadership roles in rural settings; and advancing the clinical academic leadership agenda through advocacy and research. By adopting the detailed recommendations, South Africa and other LMICs could energise management strategies, improve quality of care in rural settings and impact positively on rural health outcomes.

Molecular-based surveillance of campylobacteriosis in New Zealand--from source attribution to genomic epidemiology

Molecular-based surveillance of campylobacteriosis in New Zealand contributed to the implementation of interventions that led to a 50% reduction in notified and hospitalised cases of the country's most important zoonosis. From a pre-intervention high of 384 per 100,000 population in 2006, incidence dropped by 50% in 2008; a reduction that has been sustained since. This article illustrates many aspects of the successful use of molecular-based surveillance, including the distinction between control-focused and strategy-focused surveillance and advances in source attribution. We discuss how microbial genetic data can enhance the understanding of epidemiological explanatory and response variables and thereby enrich the epidemiological analysis. Sequence data can be fitted to evolutionary and epidemiological models to gain new insights into pathogen evolution, the nature of associations between strains of pathogens and host species, and aspects of between-host transmission. With the advent of newer sequencing technologies and the availability of rapid, high-coverage genome sequence data, such techniques may be extended and refined within the emerging discipline of genomic epidemiology. The aim of this article is to summarise the experience gained in New Zealand with molecular-based surveillance of campylobacteriosis and to discuss how this experience could be used to further advance the use of molecular tools in surveillance.

Molecular-based surveillance of campylobacteriosis in New Zealand – from source attribution to genomic epidemiology

Binary file ES_Abstracts_Final_ECDC.txt matches

Quantification of personal exposure concentrations to gasoline vehicle emissions in high-end exposure microenvironments: effects of fuel and season

Mobile-source air toxic (MSAT) levels increase in confining microenvironments (MEs) with numerous emission sources of vehicle exhaust or evaporative emissions or during high-load and cold-start conditions. Reformulated fuels are expected to reduce MSAT and ozone precursor emissions. This study, required under the Clean Air Act Section 211b, evaluated high-end exposures in cities using reformulated (methyl tertiary-butyl ether [MTBE] or ethanol [EtOH]) fuels and conventional gasoline blends. The study investigates 13 high-end MEs, sampling under enhanced exposure conditions expected to result in maximal fuel and exhaust component exposures to carbon monoxide (CO), carbon dioxide (CO2), BTEX (benzene, toluene, ethylbenzene, xylenes), MTBE, 1,3-butadiene (1,3-BD), EtOH,formaldehyde (HCHO), and acetaldehyde (CH3CHO). The authors found that day-to-day ME variations in high-end benzene, 1,3-BD, HCHO, and CO concentrations are substantial, but independent of gasoline composition and season, and related to the activity and emission rates of ME sources, which differ from day to day.

Carcinoid tumor of the lung metastatic to a previously identified pituitary adenoma

The authors present the case of a 58-year-old gentleman presenting with atypical carcinoid tumor of primary lung origin metastasizing to a previously identified pituitary macroadenoma. The patient presented with symptoms of headache and visual disturbance. Imaging revealed enlargement of a known sellar mass as well as three separate enhancing lesions in the brain parenchyma. Resection was accomplished via a transnasal transshpenoidal approach without complication. Immunoreactivity was demonstrated to synaptophysin, chromogranin, CD56, epithelial membrane antigen, and thyroid transcription factor-1. The specimen was also marked by negative staining for pituitary hormones. This case demonstrates a rare occurrence of metastastic spread of tumor to a previously identified pituitary macroadenoma.

SU-E-T-416: Performance Test Comparing Three Pre-Treatment Isocenter Localization Techniques for Single Fraction Cranial Stereotactic Radiosurgery

PURPOSE

To develop a performance test comparing three pre-treatment isocenter localization techniques when using head-frame vs. immobilization mask for cranial Stereotactic Radiosurgery (SRS). This study will compare pre-treatment positioning techniques using laser alignment vs x-ray verification using ExacTrac or On Board Imaging.

METHODS

A RANDO anthropomorphic head phantom was fitted with an in-house polystyrene insert to allow EDR2 film measurements in two orthogonal planes. A pin hole was pricked on each film to serve as a target during treatment planning. for each trial (three total), a CT scan was acquired of the phantom equipped with either an immobilization mask or invasive head frame. Treatment planning employed iPlan Image v4.1 and iPlan Dose v4.1.1. Positioning of the phantom equipped with the head-frame was performed by aligning vault lasers to coincide with cross-hair labels on a target positioner box. Setups utilizing an immobilization mask were verified by x-ray verification using ExacTrac and On Board Imaging, and if alignment were not within tolerance, then shifts were made using a 6D robotic couch. Gantry star-shot irradiation was performed using a 5mm cone to evaluate the differences between radiation isocenter and the target. The mean and standard deviations were calculated for differences in the x-, y-, and z-coordinate axes.

RESULTS

Positional accuracy using ExacTrac for mask based SRS resulted in 1.10±0.86, 0.67±0.83, and 0.59±0.48mm for cross plane, inline, and vertical measurements, respectively. Differences for frame based SRS were 0.93±0.43, 0.76±0.18, and 0.34±0.12mm for cross plane, inline, and vertical measurements, respectively. Results for mask based SRS using OBI will soon follow.

CONCLUSIONS

Although the frame-based SRS techniquegenerated smaller standard deviations, the mean difference from target to radiation isocenter for both techniques fall within the statistical uncertainty of one another. Planning margins must take into account target size when treating small lesions for both techniques. Project funded by CARTI.

Early-onset neonatal sepsis: rate and organism pattern between 2003 and 2008

OBJECTIVE

Organisms causing early-onset neonatal sepsis (EONS) have consistently changed over time. The distribution of organisms in EONS helps to influence the appropriate type of antibiotic prophylaxis strategy during labor and the antibiotics used in neonates with suspected sepsis.

STUDY DESIGN

To compare the organisms distribution for EONS between 2003 and 2008 for infants admitted to neonatal intensive care units (NICUs) in Canada. Data were retrieved from infants with a positive bacterial blood or cerebrospinal fluid culture in the first 72  h after birth who were admitted to NICUs participating in the Canadian Neonatal Network from 2003 to 2008. Comparisons of incidence rate, demographics and causative organisms were carried out between earlier cohort (2003 to 2005) and later cohort (2006 to 2008).

RESULT

A total of 405 infants had positive blood and/or cerebral spinal fluid cultures over the study period. The EONS rate was 6.8/1000 admissions (n=24969) in the earlier cohort compared with 6.2/1000 admissions (n=37484) in the later cohort (P=0.36). Rate of clinical chorioamnionitis was higher in the later cohort (38 vs 26%; P=0.02). For term infants, coagulase-negative Staphylococcus (CONS) (2.4/1000) followed by group B Streptococcus (GBS) (1.9/1000) were the most common organisms identified. For preterm infants, CONS (2.5/1000) followed by Escherichia coli (2.6/1000) were the most common organisms identified. There was a significant reduction in GBS EONS over time (P<0.01) and a trend toward an increase in other organisms.

CONCLUSION

Although the rate of EONS among neonates admitted to NICUs has not changed, the pattern of infection has changed over the past 6 years. With the increased use of prophylactic antibiotics to mothers, careful surveillance of the changing trend of bacterial organisms among neonates is warranted.

Ultrasonography aids decision-making in children with abdominal pain

INTRODUCTION

Although regular clinical assessment of the acute abdomen is considered best practice, ultrasonography confirming the presence of appendicitis will add to the decision-making process. The aim of this study was to assess the accuracy of ultrasonography and its usefulness in diagnosing acute appendicitis in a regional paediatric surgical institution.

METHODS

Retrospectively and in this order, radiology, theatre and histopathology databases were searched for patients who had presented with acute abdominal pain, patients who had undergone an appendicectomy and all appendix specimens over a two-year period. The databases were cross-referenced against each other.

RESULTS

A total of 273 non-incidental appendicectomies were performed over the study period. The negative appendicectomy rate was 16.5% and the perforation rate 23.7%. Thirty-nine per cent of children undergoing an appendicectomy had at least one pre-operative ultrasound scan. Ultrasonography as a diagnostic tool for acute appendicitis in children had a sensitivity of 83.3%, a specificity of 97.4%, a positive predictive value of 92.1% and a negative predictive value of 94.0%.

CONCLUSIONS

Ultrasonography is used liberally to aid in the decision making process of equivocal and complicated cases of acute appendicitis and it achieves good measures of accuracy. As a diagnostic tool it is unique in its ability to positively predict as well as exclude. A high negative predictive value suggests that more patients could be managed on an outpatient basis following a negative scan.

Association of a MET genetic variant with autism-associated maternal autoantibodies to fetal brain proteins and cytokine expression

The contribution of peripheral immunity to autism spectrum disorders (ASDs) risk is debated and poorly understood. Some mothers of children with ASD have autoantibodies that react to fetal brain proteins, raising the possibility that a subset of ASD cases may be associated with a maternal antibody response during gestation. The mechanism by which the maternal immune system breaks tolerance has not been addressed. We hypothesized that the mechanism may involve decreased expression of the MET receptor tyrosine kinase, an ASD risk gene that also serves as a key negative regulator of immune responsiveness. In a sample of 365 mothers, including 202 mothers of children with ASD, the functional MET promoter variant rs1858830 C allele was strongly associated with the presence of an ASD-specific 37+73-kDa band pattern of maternal autoantibodies to fetal brain proteins (P=0.003). To determine the mechanism of this genetic association, we measured MET protein and cytokine production in freshly prepared peripheral blood mononuclear cells from 76 mothers of ASD and typically developing children. The MET rs1858830 C allele was significantly associated with MET protein expression (P=0.025). Moreover, decreased expression of the regulatory cytokine IL-10 was associated with both the MET gene C allele (P=0.001) and reduced MET protein levels (P=0.002). These results indicate genetic distinction among mothers who produce ASD-associated antibodies to fetal brain proteins, and suggest a potential mechanism for how a genetically determined decrease in MET protein production may lead to a reduction in immune regulation.

Confirmation of the role of diabetes in the local recurrence of surgically resected non-small cell lung cancer

PURPOSE

We recently demonstrated that diabetes mellitus was an independent risk factor for local recurrence (LR) for patients undergoing resection of non-small cell lung cancer (NSCLC). This investigation was performed to confirm or refute this finding in a different patient cohort.

MATERIALS AND METHODS

Patients were eligible if they did not have a second primary cancer within 5 years of the original diagnosis, had at least 3-month follow-up, and did not receive radiotherapy. There were 373 and 168 patients in the original (P1) and confirmatory (P2) cohorts, respectively, with 66 and 30 patients with diabetes.

RESULTS

The median follow-up was 33 months (range, 3-98 months). Diabetes was an independent risk factor for LR in a Cox model in both the P2 (p=0.05, hazard ratio [HR] 2.15) and P1 (p=0.008, HR 1.90) cohorts, separately from BMI, glucose control, and the presence of the metabolic syndrome. The rates of LR in the patients with diabetes after combining the cohorts at 2, 3, and 5 years were 23%, 33%, and 56%, respectively; these rates were 15%, 19%, and 26% in non-diabetics. In multivariate Cox regression and competing risk analysis of the combined cohorts, the HRs for LR in patients with diabetes exceeded those of more established risk factors for LR including a 1-cm increase in tumor size and lymphovascular invasion.

CONCLUSIONS

Diabetes was confirmed to be an independent predictor of the risk of LR following resection of NSCLC.