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1.
Phys Rev Lett ; 131(2): 021802, 2023 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-37505961

RESUMO

This Letter reports one of the most precise measurements to date of the antineutrino spectrum from a purely ^{235}U-fueled reactor, made with the final dataset from the PROSPECT-I detector at the High Flux Isotope Reactor. By extracting information from previously unused detector segments, this analysis effectively doubles the statistics of the previous PROSPECT measurement. The reconstructed energy spectrum is unfolded into antineutrino energy and compared with both the Huber-Mueller model and a spectrum from a commercial reactor burning multiple fuel isotopes. A local excess over the model is observed in the 5-7 MeV energy region. Comparison of the PROSPECT results with those from commercial reactors provides new constraints on the origin of this excess, disfavoring at 2.0 and 3.7 standard deviations the hypotheses that antineutrinos from ^{235}U are solely responsible and noncontributors to the excess observed at commercial reactors, respectively.

2.
Res Rep Health Eff Inst ; (212): 1-91, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-36224709

RESUMO

INTRODUCTION: Mortality is associated with long-term exposure to fine particulate matter (particulate matter ≤2.5 µm in aerodynamic diameter; PM2.5), although the magnitude and form of these associations remain poorly understood at lower concentrations. Knowledge gaps include the shape of concentration-response curves and the lowest levels of exposure at which increased risks are evident and the occurrence and extent of associations with specific causes of death. Here, we applied improved estimates of exposure to ambient PM2.5 to national population-based cohorts in Canada, including a stacked cohort of 7.1 million people who responded to census year 1991, 1996, or 2001. The characterization of the shape of the concentration-response relationship for nonaccidental mortality and several specific causes of death at low levels of exposure was the focus of the Mortality-Air Pollution Associations in Low Exposure Environments (MAPLE) Phase 1 report. In the Phase 1 report we reported that associations between outdoor PM2.5 concentrations and nonaccidental mortality were attenuated with the addition of ozone (O3) or a measure of gaseous pollutant oxidant capacity (Ox), which was estimated from O3 and nitrogen dioxide (NO2) concentrations. This was motivated by our interests in understanding both the effects air pollutant mixtures may have on mortality and also the role of O3 as a copollutant that shares common sources and precursor emissions with those of PM2.5. In this Phase 2 report, we further explore the sensitivity of these associations with O3 and Ox, evaluate sensitivity to other factors, such as regional variation, and present ambient PM2.5 concentration-response relationships for specific causes of death. METHODS: PM2.5 concentrations were estimated at 1 km2 spatial resolution across North America using remote sensing of aerosol optical depth (AOD) combined with chemical transport model (GEOS-Chem) simulations of the AOD:surface PM2.5 mass concentration relationship, land use information, and ground monitoring. These estimates were informed and further refined with collocated measurements of PM2.5 and AOD, including targeted measurements in areas of low PM2.5 concentrations collected at five locations across Canada. Ground measurements of PM2.5 and total suspended particulate matter (TSP) mass concentrations from 1981 to 1999 were used to backcast remote-sensing-based estimates over that same time period, resulting in modeled annual surfaces from 1981 to 2016.Annual exposures to PM2.5 were then estimated for subjects in several national population-based Canadian cohorts using residential histories derived from annual postal code entries in income tax files. These cohorts included three census-based cohorts: the 1991 Canadian Census Health and Environment Cohort (CanCHEC; 2.5 million respondents), the 1996 CanCHEC (3 million respondents), the 2001 CanCHEC (3 million respondents), and a Stacked CanCHEC where duplicate records of respondents were excluded (Stacked CanCHEC; 7.1 million respondents). The Canadian Community Health Survey (CCHS) mortality cohort (mCCHS), derived from several pooled cycles of the CCHS (540,900 respondents), included additional individual information about health behaviors. Follow-up periods were completed to the end of 2016 for all cohorts. Cox proportional hazard ratios (HRs) were estimated for nonaccidental and other major causes of death using a 10-year moving average exposure and 1-year lag. All models were stratified by age, sex, immigrant status, and where appropriate, census year or survey cycle. Models were further adjusted for income adequacy quintile, visible minority status, Indigenous identity, educational attainment, labor-force status, marital status, occupation, and ecological covariates of community size, airshed, urban form, and four dimensions of the Canadian Marginalization Index (Can-Marg; instability, deprivation, dependency, and ethnic concentration). The mCCHS analyses were also adjusted for individual-level measures of smoking, alcohol consumption, fruit and vegetable consumption, body mass index (BMI), and exercise behavior.In addition to linear models, the shape of the concentration-response function was investigated using restricted cubic splines (RCS). The number of knots were selected by minimizing the Bayesian Information Criterion (BIC). Two additional models were used to examine the association between nonaccidental mortality and PM2.5. The first is the standard threshold model defined by a transformation of concentration equaling zero if the concentration was less than a specific threshold value and concentration minus the threshold value for concentrations above the threshold. The second additional model was an extension of the Shape Constrained Health Impact Function (SCHIF), the eSCHIF, which converts RCS predictions into functions potentially more suitable for use in health impact assessments. Given the RCS parameter estimates and their covariance matrix, 1,000 realizations of the RCS were simulated at concentrations from the minimum to the maximum concentration, by increments of 0.1 µg/m3. An eSCHIF was then fit to each of these RCS realizations. Thus, 1,000 eSCHIF predictions and uncertainty intervals were determined at each concentration within the total range.Sensitivity analyses were conducted to examine associations between PM2.5 and mortality when in the presence of, or stratified by tertile of, O3 or Ox. Additionally, associations between PM2.5 and mortality were assessed for sensitivity to lower concentration thresholds, where person-years below a threshold value were assigned the mean exposure within that group. We also examined the sensitivity of the shape of the nonaccidental mortality-PM2.5 association to removal of person-years at or above 12 µg/m3 (the current U.S. National Ambient Air Quality Standard) and 10 µg/m3 (the current Canadian and former [2005] World Health Organization [WHO] guideline, and current WHO Interim Target-4). Finally, differences in the shapes of PM2.5-mortality associations were assessed across broad geographic regions (airsheds) within Canada. RESULTS: The refined PM2.5 exposure estimates demonstrated improved performance relative to estimates applied previously and in the MAPLE Phase 1 report, with slightly reduced errors, including at lower ranges of concentrations (e.g., for PM2.5 <10 µg/m3).Positive associations between outdoor PM2.5 concentrations and nonaccidental mortality were consistently observed in all cohorts. In the Stacked CanCHEC analyses (1.3 million deaths), each 10-µg/m3 increase in outdoor PM2.5 concentration corresponded to an HR of 1.084 (95% confidence interval [CI]: 1.073 to 1.096) for nonaccidental mortality. For an interquartile range (IQR) increase in PM2.5 mass concentration of 4.16 µg/m3 and for a mean annual nonaccidental death rate of 92.8 per 10,000 persons (over the 1991-2016 period for cohort participants ages 25-90), this HR corresponds to an additional 31.62 deaths per 100,000 people, which is equivalent to an additional 7,848 deaths per year in Canada, based on the 2016 population. In RCS models, mean HR predictions increased from the minimum concentration of 2.5 µg/m3 to 4.5 µg/m3, flattened from 4.5 µg/m3 to 8.0 µg/m3, then increased for concentrations above 8.0 µg/m3. The threshold model results reflected this pattern with -2 log-likelihood values being equal at 2.5 µg/m3 and 8.0 µg/m3. However, mean threshold model predictions monotonically increased over the concentration range with the lower 95% CI equal to one from 2.5 µg/m3 to 8.0 µg/m3. The RCS model was a superior predictor compared with any of the threshold models, including the linear model.In the mCCHS cohort analyses inclusion of behavioral covariates did not substantially change the results for both linear and nonlinear models. We examined the sensitivity of the shape of the nonaccidental mortality-PM2.5 association to removal of person-years at or above the current U.S. and Canadian standards of 12 µg/m3 and 10 µg/m3, respectively. In the full cohort and in both restricted cohorts, a steep increase was observed from the minimum concentration of 2.5 µg/m3 to 5 µg/m3. For the full cohort and the <12 µg/m3 cohort the relationship flattened over the 5 to 9 µg/m3 range and then increased above 9 µg/m3. A similar increase was observed for the <10 µg/m3 cohort followed by a clear decline in the magnitude of predictions over the 5 to 9 µg/m3 range and an increase above 9 µg/m3. Together these results suggest that a positive association exists for concentrations >9 µg/m3 with indications of adverse effects on mortality at concentrations as low as 2.5 µg/m3.Among the other causes of death examined, PM2.5 exposures were consistently associated with an increased hazard of mortality due to ischemic heart disease, respiratory disease, cardiovascular disease, and diabetes across all cohorts. Associations were observed in the Stacked CanCHEC but not in all other cohorts for cerebrovascular disease, pneumonia, and chronic obstructive pulmonary disease (COPD) mortality. No significant associations were observed between mortality and exposure to PM2.5 for heart failure, lung cancer, and kidney failure.In sensitivity analyses, the addition of O3 and Ox attenuated associations between PM2.5 and mortality. When analyses were stratified by tertiles of copollutants, associations between PM2.5 and mortality were only observed in the highest tertile of O3 or Ox. Across broad regions of Canada, linear HR estimates and the shape of the eSCHIF varied substantially, possibly reflecting underlying differences in air pollutant mixtures not characterized by PM2.5 mass concentrations or the included gaseous pollutants. Sensitivity analyses to assess regional variation in population characteristics and access to healthcare indicated that the observed regional differences inconcentration-mortality relationships, specifically the flattening of the concentration-mortality relationship over the 5 to 9 µg/m3 range, was not likely related to variation in the makeup of the cohort or its access to healthcare, lending support to the potential role of spatially varying air pollutant mixtures not sufficiently characterized by PM2.5 mass concentrations. CONCLUSIONS: In several large, national Canadian cohorts, including a cohort of 7.1 million unique census respondents, associations were observed between exposure to PM2.5 with nonaccidental mortality and several specific causes of death. Associations with nonaccidental mortality were observed using the eSCHIF methodology at concentrations as low as 2.5 µg/m3, and there was no clear evidence in the observed data of a lower threshold, below which PM2.5 was not associated with nonaccidental mortality.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Exposição Ambiental , Mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Poluentes Atmosféricos/efeitos adversos , Poluentes Atmosféricos/análise , Poluição do Ar/efeitos adversos , Teorema de Bayes , Canadá/epidemiologia , Exposição Ambiental/efeitos adversos , Exposição Ambiental/estatística & dados numéricos , Humanos , Pessoa de Meia-Idade , Dióxido de Nitrogênio/efeitos adversos , Dióxido de Nitrogênio/análise , Oxidantes , Ozônio/efeitos adversos , Ozônio/análise , Material Particulado/efeitos adversos , Material Particulado/análise
3.
Phys Rev Lett ; 128(8): 081801, 2022 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-35275656

RESUMO

A joint determination of the reactor antineutrino spectra resulting from the fission of ^{235}U and ^{239}Pu has been carried out by the Daya Bay and PROSPECT Collaborations. This Letter reports the level of consistency of ^{235}U spectrum measurements from the two experiments and presents new results from a joint analysis of both data sets. The measurements are found to be consistent. The combined analysis reduces the degeneracy between the dominant ^{235}U and ^{239}Pu isotopes and improves the uncertainty of the ^{235}U spectral shape to about 3%. The ^{235}U and ^{239}Pu antineutrino energy spectra are unfolded from the jointly deconvolved reactor spectra using the Wiener-SVD unfolding method, providing a data-based reference for other reactor antineutrino experiments and other applications. This is the first measurement of the ^{235}U and ^{239}Pu spectra based on the combination of experiments at low- and highly enriched uranium reactors.

4.
Phys Rev Lett ; 128(8): 081802, 2022 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-35275665

RESUMO

The PROSPECT and STEREO collaborations present a combined measurement of the pure ^{235}U antineutrino spectrum, without site specific corrections or detector-dependent effects. The spectral measurements of the two highest precision experiments at research reactors are found to be compatible with χ^{2}/ndf=24.1/21, allowing a joint unfolding of the prompt energy measurements into antineutrino energy. This ν[over ¯]_{e} energy spectrum is provided to the community, and an excess of events relative to the Huber model is found in the 5-6 MeV region. When a Gaussian bump is fitted to the excess, the data-model χ^{2} value is improved, corresponding to a 2.4σ significance.

5.
Nat Commun ; 12(1): 5307, 2021 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-34489465

RESUMO

Prostate cancer is heterogeneous and patients would benefit from methods that stratify those who are likely to respond to systemic therapy. Here, we employ single-cell assays for transposase-accessible chromatin (ATAC) and RNA sequencing in models of early treatment response and resistance to enzalutamide. In doing so, we identify pre-existing and treatment-persistent cell subpopulations that possess regenerative potential when subjected to treatment. We find distinct chromatin landscapes associated with enzalutamide treatment and resistance that are linked to alternative transcriptional programs. Transcriptional profiles characteristic of persistent cells are able to stratify the treatment response of patients. Ultimately, we show that defining changes in chromatin and gene expression in single-cell populations from pre-clinical models can reveal as yet unrecognized molecular predictors of treatment response. This suggests that the application of single-cell methods with high analytical resolution in pre-clinical models may powerfully inform clinical decision-making.


Assuntos
Cromatina/química , DNA de Neoplasias/genética , Resistencia a Medicamentos Antineoplásicos/genética , Proteínas de Neoplasias/genética , Neoplasias da Próstata/genética , Transcriptoma , Antineoplásicos/uso terapêutico , Benzamidas/uso terapêutico , Linhagem Celular Tumoral , Cromatina/metabolismo , DNA de Neoplasias/metabolismo , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Proteínas de Neoplasias/metabolismo , Nitrilas/uso terapêutico , Feniltioidantoína/uso terapêutico , Próstata/metabolismo , Próstata/patologia , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/mortalidade , Neoplasias da Próstata/patologia , Análise de Sequência de RNA/métodos , Análise de Célula Única/métodos , Análise de Sobrevida , Sequenciamento do Exoma
6.
Scand J Urol ; 55(6): 448-454, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34498951

RESUMO

PURPOSE: To investigate the role of clinical parameters and immunohistochemical (IHC) biomarkers in their feasibility to predict the effect of neo-adjuvant chemotherapy (NAC) in patients with muscle-invasive urothelial bladder cancer (MIBC). MATERIALS AND METHODS: The first 76 consecutive patients with MIBC treated with NAC and radical cystectomy in two University hospitals in Finland between 2008 and 2013 were chosen for this study. After excluding patients with non-urothelial cancer, less than two cycles of chemotherapy, no tissue material for IHC analysis or non-muscle-invasive bladder cancer in re-review, 59 patients were included in the final analysis. A tissue microarray block was constructed from the transurethral resection samples and IHC stainings of Ki-67, p53, Her-2 and EGFR were made. The correlations between histological features in transurethral resection samples and immune-histochemical stainings were calculated. The associations of clinicopathological parameters and IHC stainings with NAC response were evaluated. Factors affecting survival were estimated. RESULTS: The complete response rate after NAC was 44%. A higher number of chemotherapy cycles was associated with better response to neo-adjuvant chemotherapy. No response to neo-adjuvant chemotherapy and female gender was associated with decreased cancer-specific survival. The IHC stainings used failed to show an association with neo-adjuvant chemotherapy response and overall or cancer specific survival. CONCLUSIONS: Patients who do not respond to neo-adjuvant chemotherapy do significantly worse than responders. This study could not find clinical tools to distinguish responders from non-responders. Further studies preferably with larger cohorts addressing this issue are warranted to improve the selection of patients for neo-adjuvant chemotherapy.


Assuntos
Neoplasias da Bexiga Urinária , Quimioterapia Adjuvante , Cistectomia , Feminino , Humanos , Terapia Neoadjuvante , Invasividade Neoplásica , Estudos Retrospectivos , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/cirurgia , Urotélio
7.
Phys Rev C ; 1012020.
Artigo em Inglês | MEDLINE | ID: mdl-33336123

RESUMO

Reactor neutrino experiments have seen major improvements in precision in recent years. With the experimental uncertainties becoming lower than those from theory, carefully considering all sources of ν ¯ e is important when making theoretical predictions. One source of ν ¯ e that is often neglected arises from the irradiation of the nonfuel materials in reactors. The ν ¯ e rates and energies from these sources vary widely based on the reactor type, configuration, and sampling stage during the reactor cycle and have to be carefully considered for each experiment independently. In this article, we present a formalism for selecting the possible ν ¯ e sources arising from the neutron captures on reactor and target materials. We apply this formalism to the High Flux Isotope Reactor (HFIR) at Oak Ridge National Laboratory, the ν ¯ e source for the the Precision Reactor Oscillation and Spectrum Measurement (PROSPECT) experiment. Overall, we observe that the nonfuel ν ¯ e contributions from HFIR to PROSPECT amount to 1% above the inverse beta decay threshold with a maximum contribution of 9% in the 1.8-2.0 MeV range. Nonfuel contributions can be particularly high for research reactors like HFIR because of the choice of structural and reflector material in addition to the intentional irradiation of target material for isotope production. We show that typical commercial pressurized water reactors fueled with low-enriched uranium will have significantly smaller nonfuel ν ¯ e contribution.

8.
J Dairy Sci ; 103(8): 7569-7584, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32475674

RESUMO

Postpasteurization contamination (PPC) with gram-negative bacteria adversely affects the quality and shelf-life of milk through the development of flavor, odor, texture, and visual defects. Through evaluation of milk quality at 4 large fluid milk processing facilities in the northeast United States, we examined the efficacy of 3 strategies designed to reduce the occurrence of PPC in fluid milk: (1) employee training (focusing on good manufacturing practices) alone and (2) with concurrent implementation of modified clean-in-place chemistry and (3) preventive maintenance (PM) focused on replacement of wearable rubber components. Despite increases in employee knowledge and self-reported behavior change, microbiological evaluation of fluid milk before and after interventions indicated that neither training alone nor training combined with modified clean-in-place interventions significantly decreased PPC. Furthermore, characterization of gram-negative bacterial isolates from milk suggested that specific bacterial taxonomic groups (notably, Pseudomonas sequence types) continued to contribute to PPC even after interventions and that no major changes in the composition of the spoilage-associated microbial populations occurred as a consequence of the interventions. More specifically, in 3 of 4 facilities, gram-negative bacteria with identical 16S rDNA sequence types were isolated on multiple occasions. Evaluation of a PM intervention showed that used rubber goods harbored PPC-associated bacteria and that PPC may have been less frequent following a PM intervention in which wearable rubber goods were replaced (reduction from 3/3 samples with PPC before to 1/3 samples after). Overall, our findings suggest that commonly used "broad stroke interventions" may have a limited effect on reducing PPC. Our case study also demonstrates the inherent complexities of identifying and successfully addressing sanitation problems in large and complex fluid milk processing facilities. For example, broad changes to sanitation practices without improvements in PM and sanitary equipment design may not always lead to reduced PPC. Our data also indicate that although short-term evaluations, such as pre- and post-tests for employee training, may suggest improvements after corrective and preventive actions, extensive microbial testing, ideally in combination with isolate characterization, may be necessary to evaluate return on investment of different interventions.


Assuntos
Bovinos , Indústria de Laticínios/educação , Contaminação de Alimentos/prevenção & controle , Leite/normas , Animais , Bactérias/genética , Bactérias/isolamento & purificação , DNA Ribossômico/análise , Feminino , Contaminação de Alimentos/análise , Temperatura Alta , Higiene , Manutenção , Leite/química , Leite/microbiologia , New England , Pasteurização , Pseudomonas/isolamento & purificação , Paladar
9.
Exp Mech ; 59(9): 1261-1274, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31787777

RESUMO

Growth plate cartilage resides near the ends of long bones and is the primary driver of skeletal growth. During growth, both intrinsically and extrinsically generated mechanical stresses act on chondrocytes in the growth plate. Although the role of mechanical stresses in promoting tissue growth and homeostasis has been strongly demonstrated in articular cartilage of the major skeletal joints, effects of stresses on growth plate cartilage and bone growth are not as well established. Here, we review the literature on mechanobiology in growth plate cartilage at macroscopic and microscopic scales, with particular emphasis on comparison of results obtained using different methodological approaches, as well as from whole animal and in vitro experiments. To answer these questions, macroscopic mechanical stimulators have been developed and applied to study mechanobiology of growth plate cartilage and chondrocytes. However, the previous approaches have tested a limited number of stress conditions, and the mechanobiology of a single chondrocyte has not been well studied due to limitations of the macroscopic mechanical stimulators. We explore how microfluidics devices can overcome these limitations and improve current understanding of growth plate chondrocyte mechanobiology. In particular, microfluidic devices can generate multiple stress conditions in a single platform and enable real-time monitoring of metabolism and cellular behavior using optical microscopy. Systematic characterization of the chondrocytes using microfluidics will enhance our understanding of how to use mechanical stresses to control the bone growth and the properties of tissue-engineered growth plate cartilage.

10.
Phys Rev Lett ; 122(25): 251801, 2019 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-31347897

RESUMO

This Letter reports the first measurement of the ^{235}U ν[over ¯]_{e} energy spectrum by PROSPECT, the Precision Reactor Oscillation and Spectrum experiment, operating 7.9 m from the 85 MW_{th} highly enriched uranium (HEU) High Flux Isotope Reactor. With a surface-based, segmented detector, PROSPECT has observed 31678±304(stat) ν[over ¯]_{e}-induced inverse beta decays, the largest sample from HEU fission to date, 99% of which are attributed to ^{235}U. Despite broad agreement, comparison of the Huber ^{235}U model to the measured spectrum produces a χ^{2}/ndf=51.4/31, driven primarily by deviations in two localized energy regions. The measured ^{235}U spectrum shape is consistent with a deviation relative to prediction equal in size to that observed at low-enriched uranium power reactors in the ν[over ¯]_{e} energy region of 5-7 MeV.

11.
Res Rep Health Eff Inst ; (203): 1-87, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31909580

RESUMO

INTRODUCTION: Fine particulate matter (particulate matter ≤2.5 µm in aerodynamic diameter, or PM2.5) is associated with mortality, but the lower range of relevant concentrations is unknown. Novel satellite-derived estimates of outdoor PM2.5 concentrations were applied to several large population-based cohorts, and the shape of the relationship with nonaccidental mortality was characterized, with emphasis on the low concentrations (<12 µg/m3) observed throughout Canada. METHODS: Annual satellite-derived estimates of outdoor PM2.5 concentrations were developed at 1-km2 spatial resolution across Canada for 2000-2016 and backcasted to 1981 using remote sensing, chemical transport models, and ground monitoring data. Targeted ground-based measurements were conducted to measure the relationship between columnar aerosol optical depth (AOD) and ground-level PM2.5. Both existing and targeted ground-based measurements were analyzed to develop improved exposure data sets for subsequent epidemiological analyses.Residential histories derived from annual tax records were used to estimate PM2.5 exposures for subjects whose ages ranged from 25 to 90 years. About 8.5 million were from three Canadian Census Health and Environment Cohort (CanCHEC) analytic files and another 540,900 were Canadian Community Health Survey (CCHS) participants. Mortality was linked through the year 2016. Hazard ratios (HR) were estimated with Cox Proportional Hazard models using a 3-year moving average exposure with a 1-year lag, with the year of follow-up as the time axis. All models were stratified by 5-year age groups, sex, and immigrant status. Covariates were based on directed acyclical graphs (DAG), and included contextual variables (airshed, community size, neighborhood dependence, neighborhood deprivation, ethnic concentration, neighborhood instability, and urban form). A second model was examined including the DAG-based covariates as well as all subject-level risk factors (income, education, marital status, indigenous identity, employment status, occupational class, and visible minority status) available in each cohort. Additional subject-level behavioral covariates (fruit and vegetable consumption, leisure exercise frequency, alcohol consumption, smoking, and body mass index [BMI]) were included in the CCHS analysis.Sensitivity analyses evaluated adjustment for covariates and gaseous copollutants (nitrogen dioxide [NO2] and ozone [O3]), as well as exposure time windows and spatial scales. Estimates were evaluated across strata of age, sex, and immigrant status. The shape of the PM2.5-mortality association was examined by first fitting restricted cubic splines (RCS) with a large number of knots and then fitting the shape-constrained health impact function (SCHIF) to the RCS predictions and their standard errors (SE). This method provides graphical results indicating the RCS predictions, as a nonparametric means of characterizing the concentration-response relationship in detail and the resulting mean SCHIF and accompanying uncertainty as a parametric summary.Sensitivity analyses were conducted in the CCHS cohort to evaluate the potential influence of unmeasured covariates on air pollution risk estimates. Specifically, survival models with all available risk factors were fit and compared with models that omitted covariates not available in the CanCHEC cohorts. In addition, the PM2.5 risk estimate in the CanCHEC cohort was indirectly adjusted for multiple individual-level risk factors by estimating the association between PM2.5 and these covariates within the CCHS. RESULTS: Satellite-derived PM2.5 estimates were low and highly correlated with ground monitors. HR estimates (per 10-µg/m3 increase in PM2.5) were similar for the 1991 (1.041, 95% confidence interval [CI]: 1.016-1.066) and 1996 (1.041, 1.024-1.059) CanCHEC cohorts with a larger estimate observed for the 2001 cohort (1.084, 1.060-1.108). The pooled cohort HR estimate was 1.053 (1.041-1.065). In the CCHS an analogous model indicated a HR of 1.13 (95% CI: 1.06-1.21), which was reduced slightly with the addition of behavioral covariates (1.11, 1.04-1.18). In each of the CanCHEC cohorts, the RCS increased rapidly over lower concentrations, slightly declining between the 25th and 75th percentiles and then increasing beyond the 75th percentile. The steepness of the increase in the RCS over lower concentrations diminished as the cohort start date increased. The SCHIFs displayed a supralinear association in each of the three CanCHEC cohorts and in the CCHS cohort.In sensitivity analyses conducted with the 2001 CanCHEC, longer moving averages (1, 3, and 8 years) and smaller spatial scales (1 km2 vs. 10 km2) of exposure assignment resulted in larger associations between PM2.5 and mortality. In both the CCHS and CanCHEC analyses, the relationship between nonaccidental mortality and PM2.5 was attenuated when O3 or a weighted measure of oxidant gases was included in models. In the CCHS analysis, but not in CanCHEC, PM2.5 HRs were also attenuated by the inclusion of NO2. Application of the indirect adjustment and comparisons within the CCHS analysis suggests that missing data on behavioral risk factors for mortality had little impact on the magnitude of PM2.5-mortality associations. While immigrants displayed improved overall survival compared with those born in Canada, their sensitivity to PM2.5 was similar to or larger than that for nonimmigrants, with differences between immigrants and nonimmigrants decreasing in the more recent cohorts. CONCLUSIONS: In several large population-based cohorts exposed to low levels of air pollution, consistent associations were observed between PM2.5 and nonaccidental mortality for concentrations as low as 5 µg/m3. This relationship was supralinear with no apparent threshold or sublinear association.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/análise , Exposição Ambiental/análise , Mortalidade/tendências , Material Particulado/análise , Adulto , Idoso , Idoso de 80 Anos ou mais , Canadá/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Estados Unidos/epidemiologia
12.
Transbound Emerg Dis ; 65(2): e272-e283, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29194985

RESUMO

Microarray technology can be useful for pathogen detection as it allows simultaneous interrogation of the presence or absence of a large number of genetic signatures. However, most microarray assays are labour-intensive and time-consuming to perform. This study describes the development and initial evaluation of a multiplex reverse transcription (RT)-PCR and novel accompanying automated electronic microarray assay for simultaneous detection and differentiation of seven important viruses that affect swine (foot-and-mouth disease virus [FMDV], swine vesicular disease virus [SVDV], vesicular exanthema of swine virus [VESV], African swine fever virus [ASFV], classical swine fever virus [CSFV], porcine respiratory and reproductive syndrome virus [PRRSV] and porcine circovirus type 2 [PCV2]). The novel electronic microarray assay utilizes a single, user-friendly instrument that integrates and automates capture probe printing, hybridization, washing and reporting on a disposable electronic microarray cartridge with 400 features. This assay accurately detected and identified a total of 68 isolates of the seven targeted virus species including 23 samples of FMDV, representing all seven serotypes, and 10 CSFV strains, representing all three genotypes. The assay successfully detected viruses in clinical samples from the field, experimentally infected animals (as early as 1 day post-infection (dpi) for FMDV and SVDV, 4 dpi for ASFV, 5 dpi for CSFV), as well as in biological material that were spiked with target viruses. The limit of detection was 10 copies/µl for ASFV, PCV2 and PRRSV, 100 copies/µl for SVDV, CSFV, VESV and 1,000 copies/µl for FMDV. The electronic microarray component had reduced analytical sensitivity for several of the target viruses when compared with the multiplex RT-PCR. The integration of capture probe printing allows custom onsite array printing as needed, while electrophoretically driven hybridization generates results faster than conventional microarrays that rely on passive hybridization. With further refinement, this novel, rapid, highly automated microarray technology has potential applications in multipathogen surveillance of livestock diseases.


Assuntos
Reação em Cadeia da Polimerase Multiplex/veterinária , Doenças dos Suínos/virologia , Viroses/veterinária , Vírus/classificação , Vírus da Febre Suína Africana/classificação , Vírus da Febre Suína Africana/genética , Animais , Circovirus/classificação , Circovirus/genética , Vírus da Febre Suína Clássica/classificação , Vírus da Febre Suína Clássica/genética , Enterovirus Humano B/classificação , Enterovirus Humano B/genética , Vírus da Febre Aftosa/classificação , Vírus da Febre Aftosa/genética , Limite de Detecção , Análise em Microsséries/veterinária , Vírus da Síndrome Respiratória e Reprodutiva Suína/classificação , Vírus da Síndrome Respiratória e Reprodutiva Suína/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária , Suínos , Vírus do Exantema Vesicular de Suínos/classificação , Vírus do Exantema Vesicular de Suínos/genética , Viroses/virologia , Vírus/genética
13.
Phys Rev Lett ; 121(25): 251802, 2018 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-30608854

RESUMO

This Letter reports the first scientific results from the observation of antineutrinos emitted by fission products of ^{235}U at the High Flux Isotope Reactor. PROSPECT, the Precision Reactor Oscillation and Spectrum Experiment, consists of a segmented 4 ton ^{6}Li-doped liquid scintillator detector covering a baseline range of 7-9 m from the reactor and operating under less than 1 m water equivalent overburden. Data collected during 33 live days of reactor operation at a nominal power of 85 MW yield a detection of 25 461±283 (stat) inverse beta decays. Observation of reactor antineutrinos can be achieved in PROSPECT at 5σ statistical significance within 2 h of on-surface reactor-on data taking. A reactor model independent analysis of the inverse beta decay prompt energy spectrum as a function of baseline constrains significant portions of the previously allowed sterile neutrino oscillation parameter space at 95% confidence level and disfavors the best fit of the reactor antineutrino anomaly at 2.2σ confidence level.

14.
Vox Sang ; 112(3): 210-218, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28220519

RESUMO

BACKGROUND AND OBJECTIVES: Pathogen reduction technology using amustaline (S-303) was developed to reduce the risk of transfusion-transmitted infection and adverse effects of residual leucocytes. In this study, the viability of red blood cells (RBCs) prepared with a second-generation process and stored for 35 days was evaluated in two different blood centres. MATERIALS AND METHODS: In a single-blind, randomized, controlled, two-period crossover study (n = 42 healthy subjects), amustaline-treated (Test) or Control RBCs were prepared in random sequence and stored for 35 days. On day 35, an aliquot of 51 Cr/99m Tc radiolabeled RBCs was transfused. In a subgroup of 26 evaluable subjects, 24-h RBC post-transfusion recovery, mean life span, median life span (T50 ) and life span area under the curve (AUC) were analysed. RESULTS: The mean 24-h post-transfusion recovery of Test and Control RBCs was comparable (83·2 ± 5·2 and 84·9 ± 5·9%, respectively; P = 0·06) and consistent with the US Food and Drug Administration (FDA) criteria for acceptable RBC viability. There were differences in the T50 between Test and Control RBCs (33·5 and 39·7 days, respectively; P < 0·001), however, these were within published reference ranges of 28-35 days. The AUC (per cent surviving × days) for Test and Control RBCs was similar (22·6 and 23·1 per cent surviving cells × days, respectively; P > 0·05). Following infusion of Test RBCs, there were no clinically relevant abnormal laboratory values or adverse events. CONCLUSION: RBCs prepared using amustaline pathogen reduction meet the FDA criteria for post-transfusion recovery and are metabolically and physiologically appropriate for transfusion following 35 days of storage.


Assuntos
Acridinas/farmacologia , Preservação de Sangue , Eritrócitos/efeitos dos fármacos , Compostos de Mostarda Nitrogenada/farmacologia , Acridinas/química , Adulto , Idoso , Área Sob a Curva , Sobrevivência Celular/efeitos dos fármacos , Isótopos do Cromo/química , Estudos Cross-Over , Contagem de Eritrócitos , Transfusão de Eritrócitos/efeitos adversos , Eritrócitos/química , Eritrócitos/citologia , Eritrócitos/metabolismo , Feminino , Meia-Vida , Hematoma/etiologia , Humanos , Marcação por Isótopo , Masculino , Viabilidade Microbiana/efeitos dos fármacos , Pessoa de Meia-Idade , Compostos de Mostarda Nitrogenada/química , Curva ROC , Método Simples-Cego , Tecnécio/química , Fatores de Tempo , Inativação de Vírus/efeitos dos fármacos , Adulto Jovem
15.
Transbound Emerg Dis ; 64(3): 834-848, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26662640

RESUMO

Porcine respiratory disease complex (PRDC) is one of the most important health concerns for pig producers and can involve multiple viral and bacterial pathogens. No simple, single-reaction diagnostic test currently exists for the simultaneous detection of major pathogens commonly associated with PRDC. Furthermore, the detection of most of the bacterial pathogens implicated in PRDC currently requires time-consuming culture-based methods that can take several days to obtain results. In this study, a novel prototype automated microarray that integrates and automates all steps of post-PCR microarray processing for the simultaneous detection and typing of eight bacteria and viruses commonly associated with PRDC is described along with associated multiplex reverse transcriptase PCR. The user-friendly assay detected and differentiated between four viruses [porcine reproductive and respiratory syndrome virus (PRRSV), influenza A virus, porcine circovirus type 2, porcine respiratory corona virus], four bacteria (Mycoplasma hyopneumoniae, Pasteurella multocida, Salmonella enterica serovar Choleraesuis, Streptococcus suis), and further differentiated between type 1 and type 2 PRRSV as well as toxigenic and non-toxigenic P. multocida. The assay accurately identified and typed a panel of 34 strains representing the eight targeted pathogens and was negative when tested with 34 relevant and/or closely related non-target bacterial and viral species. All targets were also identified singly or in combination in a panel of clinical lung samples and/or experimentally inoculated biological material.


Assuntos
Bactérias/isolamento & purificação , Reação em Cadeia da Polimerase Multiplex/veterinária , Análise Serial de Proteínas/veterinária , Doenças dos Suínos/diagnóstico , Vírus/isolamento & purificação , Animais , Bactérias/classificação , Análise Serial de Proteínas/métodos , Sensibilidade e Especificidade , Suínos , Doenças dos Suínos/microbiologia , Doenças dos Suínos/virologia , Vírus/classificação
16.
Prostate Cancer Prostatic Dis ; 19(4): 417-422, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27526964

RESUMO

BACKGROUND: The most severe manifestations of prostate biopsy complications are bacteremic infections. These complications are increasing alarmingly. METHODS: A retrospective cohort study of 17 183 transrectal prostate biopsies performed at the Helsinki and Uusimaa hospital district in southern Finland during 2005-2013. Biopsies were linked to a database of positive blood cultures, yielding 111 bacteremic cases, and yearly bacteremia rates were determined. By multiple regression analysis, demographic risk factors of the whole biopsy cohort for developing bacteremia or fluoroquinolone (FQ)-resistant bacteremia were studied. Clinical risk factors for bacteremia caused by an FQ-resistant organism and for serious bacteremic outcomes were studied by univariate and multivariate analyzes. RESULTS: The average bacteremia rate was 0.7% (111 of 17 183 biopsies) and an increase was observed from 0.5% in 2005 (95% confidence interval (CI): 0.3-0.9) to 1.2% in 2012 (95% CI 0.8-1.8); 53.2% were caused by an FQ-resistant organism. In univariate regression analysis, previous biopsy sessions and increasing calendar year of biopsy associated with the risk of developing bacteremia (odds ratio (OR) 1.232, 95% CI: 1.020-1.488, P=0.030 and OR 1.164, 95% CI: 1.079-1.255, P<0.001, respectively), but only increasing calendar year of biopsy remained statistically significant (OR 1.155, 95% CI: 1.070-1.247, P<0.001) in multivariate analysis. Foreign travel within 3 months was associated with FQ resistance in multivariate analysis (OR 7.158, 95% CI: 1.042 to infinite, P=0.045). The study failed to show any significant clinical risk factors for serious bacteremic outcomes (requiring intensive care, developing deep infection foci or death). CONCLUSIONS: The postbiopsy bacteremia rate doubled during the study period and half of the cases were caused by FQ-resistant organisms. Recent foreign travel increased the risk for FQ resistance. Future research efforts should be aimed at better identifying risk factors, targeted prophylaxis and reducing the need for biopsies.


Assuntos
Bacteriemia/etiologia , Biópsia/efeitos adversos , Próstata/patologia , Idoso , Antibacterianos/uso terapêutico , Bacteriemia/tratamento farmacológico , Finlândia , Fluoroquinolonas/uso terapêutico , Humanos , Masculino , Neoplasias da Próstata/patologia , Reto/patologia , Estudos Retrospectivos , Fatores de Risco
17.
Sci Rep ; 6: 24388, 2016 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-27087555

RESUMO

Weapons-grade uranium and plutonium could be used as nuclear explosives with extreme destructive potential. The problem of their detection, especially in standard cargo containers during transit, has been described as "searching for a needle in a haystack" because of the inherently low rate of spontaneous emission of characteristic penetrating radiation and the ease of its shielding. Currently, the only practical approach for uncovering well-shielded special nuclear materials is by use of active interrogation using an external radiation source. However, the similarity of these materials to shielding and the required radiation doses that may exceed regulatory limits prevent this method from being widely used in practice. We introduce a low-dose active detection technique, referred to as low-energy nuclear reaction imaging, which exploits the physics of interactions of multi-MeV monoenergetic photons and neutrons to simultaneously measure the material's areal density and effective atomic number, while confirming the presence of fissionable materials by observing the beta-delayed neutron emission. For the first time, we demonstrate identification and imaging of uranium with this novel technique using a simple yet robust source, setting the stage for its wide adoption in security applications.

18.
Transfus Med ; 26(3): 208-14, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27006102

RESUMO

BACKGROUND AND OBJECTIVES: The pathogen inactivation (PI) INTERCEPT Blood System for Red Blood Cells utilises amustaline (S-303) to inactivate a broad range of pathogens in red cell concentrates (RCC). The aim of this study was to investigate the effect on red cell quality of INTERCEPT treatment with and without prion reduction. METHODS/MATERIALS: Five pools of five RCC each were prepared. These were split and treated as follows: (i) stored at 2-6 °C for 18 h, (ii) stored at 18-24 °C for 18 h, (iii) PI-treated, (iv) PI-treated then prion reduced and (v) prion reduced then PI-treated. Prior to storage, PI-treated RCC underwent an exchange step to remove S-303 and other breakdown products. Components were tested throughout 35 days of storage for in vitro parameters of red cell quality. RESULTS: All RCC met specification for volume and haemoglobin content. Haemolysis, microvesicle formation, supernatant potassium and deformability were lower and ATP levels higher in PI-treated units when compared with control units. The effect of prion reduction in addition to PI treatment was minimal in all parameters tested except haemolysis, which was increased in units prion-reduced after being PI-treated. CONCLUSION: The PI-treatment process did not increase red cell haemolysis or decrease ATP levels over storage. The lower haemolysis and supernatant potassium levels in treated RCC compared with control RCC were attributed to the exchange step. The effects of combining PI treatment and prion reduction were not more than additive when prion reduction precedes PI treatment.


Assuntos
Segurança do Sangue/métodos , Desinfecção/métodos , Eritrócitos , Príons , Feminino , Humanos , Masculino
19.
Transbound Emerg Dis ; 63(5): e395-402, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25644051

RESUMO

Classical swine fever (CSF) is an OIE-listed disease that can have a severe impact on the swine industry. User-friendly, sensitive, rapid diagnostic tests that utilize low-cost field-deployable instruments for CSF diagnosis can be useful for disease surveillance and outbreak monitoring. In this study, we describe validation of a new probe-based insulated isothermal reverse transcriptase PCR (iiRT-PCR) assay for rapid detection of classical swine fever virus (CSFV) on a compact, user-friendly device (POCKIT(™) Nucleic Acid Analyzer) that does not need data interpretation by the user. The assay accurately detected CSFV RNA from a diverse panel of 33 CSFV strains representing all three genotypes plus an additional in vitro-transcribed RNA from cloned sequences representing a vaccine strain. No cross-reactivity was observed with a panel of 18 viruses associated with livestock including eight other pestivirus strains (bovine viral diarrhoea virus type 1 and type 2, border disease virus, HoBi atypical pestivirus), African swine fever virus, swine vesicular disease virus, swine influenza virus, porcine respiratory and reproductive syndrome virus, porcine circovirus 1, porcine circovirus 2, porcine respiratory coronavirus, vesicular exanthema of swine virus, bovine herpes virus type 1 and vesicular stomatitis virus. The iiRT-PCR assay accurately detected CSFV as early as 2 days post-inoculation in RNA extracted from serum samples of experimentally infected pigs, before appearance of clinical signs. The limit of detection (LOD95% ) calculated by probit regression analysis was 23 copies per reaction. The assay has a sample to answer turnaround time of less than an hour using extracted RNA or diluted or low volume of neat serum. The user-friendly, compact device that automatically analyses and displays results could potentially be a useful tool for surveillance and monitoring of CSF in a disease outbreak.


Assuntos
Vírus da Febre Suína Clássica/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa/instrumentação , Animais , Genótipo , Sistemas Automatizados de Assistência Junto ao Leito , RNA Viral/isolamento & purificação , Sensibilidade e Especificidade , Suínos
20.
Biologicals ; 38(1): 14-9, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19995680

RESUMO

A pathogen inactivation (PI) process has been developed using the frangible anchor linker effector (FRALE) compound S-303. A series of experiments were performed in whole blood (WB) to measure the level of viral and bacterial inactivation. The results showed that 0.2mM S-303 and 2mM glutathione (GSH) inactivated >6.5 logs of HIV, >5.7 logs of Bluetongue virus, >7.0 logs of Yersinia enterocolitica, 4.2 logs of Serratia marcescens, and 7.5 logs of Staphylococcus epidermidis. Recent development for S-303 is focused on optimization of the PI process for red blood cell concentrates (RBC). A series of studies in RBC showed that 0.2mM S-303 and 20mM GSH inactivated approximately 5 logs or greater of Y. enterocolitica, E. coli, S. marcescens, S. aureus, HIV, bovine viral diarrhoea virus, bluetongue virus and human adenovirus 5. In both applications of the S-303 process, in vitro parameters of RBC function and physiology were retained compared to conventional RBC. Results from these studies indicate that S-303 can be applicable for PI of RBC and WB.


Assuntos
Acridinas/farmacologia , Preservação de Sangue/métodos , Patógenos Transmitidos pelo Sangue , Sangue/efeitos dos fármacos , Eritrócitos/efeitos dos fármacos , Compostos de Mostarda Nitrogenada/farmacologia , Alquilantes/farmacologia , Animais , Sangue/microbiologia , Sangue/virologia , Patógenos Transmitidos pelo Sangue/isolamento & purificação , Bovinos , Células Cultivadas , Contagem de Colônia Microbiana , Desinfetantes/farmacologia , Desinfecção/métodos , Eritrócitos/microbiologia , Eritrócitos/virologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/fisiologia , Estudos de Viabilidade , Humanos , Análise por Pareamento , Controle de Qualidade , Staphylococcaceae/efeitos dos fármacos , Staphylococcaceae/fisiologia , Yersinia enterocolitica/efeitos dos fármacos , Yersinia enterocolitica/fisiologia
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