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1.
Integr Environ Assess Manag ; 20(4): 975-980, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38329199

ABSTRACT

Risks posed by environmental exposure to chemicals are routinely assessed to inform activities ranging from environmental status reporting to authorization and registration of chemicals for commercial uses. Environmental risk assessment generally relies on two key values generated from exposure data and ecotoxicity data. Data sets of measured concentrations of chemicals in environmental matrices, referred to here as exposure data, are widely used to support environmental risk management, decision-making, and reporting, such as for chemical screening, ecological or human health risk assessments, and establishment of guidelines. Practitioners have developed schemes to determine the suitability of ecotoxicity data for specific purposes, focused on evaluating reliability and relevance, but analogous schemes are not available for exposure data. Moreover, regulatory guidance arguably provides less resolution on reporting and evaluating exposure data sets compared to ecotoxicity data. The evaluation of exposure data sets is subject to limitations from variable or unreported data quality objectives and/or from differences in expert judgments, potentially introducing bias and leading to decisions based on flawed and/or inconsistent information. Exposure data sets should be evaluated for reliability and relevance prior to use in environmental assessments. This paper is the first of a four-paper series detailing the outcomes of a Society of Environmental Toxicology and Chemistry technical workshop that has developed Criteria for Reporting and Evaluating Exposure Datasets (CREED). The workshop participants developed practical, systematic criteria for consistent and transparent evaluation of the reliability (quality) and relevance (fitness for purpose) of exposure data. This guidance should apply to many different (unspecified) purposes of assessment. CREED can be used to evaluate existing data sets, but can also inform data generators interested in improving their data collection and reporting to maximize data utility to other users. This first paper details existing frameworks for the evaluation of exposure data sets and demonstrates the need for CREED, drawing from different regulatory assessments, and describes the technical workshop. Integr Environ Assess Manag 2024;20:975-980. © 2024 SETAC.


Subject(s)
Environmental Exposure , Environmental Monitoring , Risk Assessment/methods , Environmental Exposure/statistics & numerical data , Environmental Monitoring/methods , Ecotoxicology/methods , Environmental Pollutants/analysis , Reproducibility of Results , Humans
2.
Integr Environ Assess Manag ; 20(4): 1004-1018, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38099403

ABSTRACT

Environmental exposure data are used by decision-makers to assess environmental risks and implement actions to mitigate risks from contaminants. The first article in this series summarized the available evaluation schemes for environmental exposure data, of which there are few compared to those available for environmental hazard data. The second article covered the assessment of the reliability of environmental exposure data sets under the Criteria for the Reporting and Evaluation of Exposure Data (CREED). The aim of this article is to provide an overview and practical guidance on the relevance assessment in the context of the CREED approach for evaluating exposure monitoring data sets. Systematically considering relevance is critical for both evaluating existing data sets and for optimizing the design of new monitoring studies. Relevance is defined here as the degree of suitability or appropriateness of a data set to address a specific purpose or to answer the questions that have been defined by the assessor or for those generating exposure data. The purpose definition will be the foundation for the relevance assessment, to clarify how the assessor should rate the assessment criteria (fully met, partly met, not met/inappropriate, not reported, not applicable). This will provide transparency for anyone reviewing the outcomes. An explicit gap analysis (i.e., an articulation of the data set limitations for the stated purpose) is an important outcome of the relevance assessment. The relevance evaluation approach is demonstrated with three case studies, all relating to the freshwater aquatic environment, where the data sets are scored as relevant with or without restrictions, not relevant, or not assignable. The case studies represent both organic and inorganic constituents, and have different data characteristics (e.g., percentage of censored data, sampling frequencies, relation to supporting parameters). Integr Environ Assess Manag 2024;20:1004-1018. © 2023 SETAC.


Subject(s)
Environmental Exposure , Environmental Monitoring , Environmental Monitoring/methods , Environmental Exposure/statistics & numerical data , Risk Assessment/methods , Environmental Pollutants/analysis , Reproducibility of Results
3.
Ecol Evol ; 6(22): 8075-8084, 2016 11.
Article in English | MEDLINE | ID: mdl-27878079

ABSTRACT

The acreage planted in corn and soybean crops is vast, and these crops contribute substantially to the world economy. The agricultural practices employed for farming these crops have major effects on ecosystem health at a worldwide scale. The microbial communities living in agricultural soils significantly contribute to nutrient uptake and cycling and can have both positive and negative impacts on the crops growing with them. In this study, we examined the impact of the crop planted and soil tillage on nutrient levels, microbial communities, and the biochemical pathways present in the soil. We found that farming practice, that is conventional tillage versus no-till, had a much greater impact on nearly everything measured compared to the crop planted. No-till fields tended to have higher nutrient levels and distinct microbial communities. Moreover, no-till fields had more DNA sequences associated with key nitrogen cycle processes, suggesting that the microbial communities were more active in cycling nitrogen. Our results indicate that tilling of agricultural soil may magnify the degree of nutrient waste and runoff by altering nutrient cycles through changes to microbial communities. Currently, a minority of acreage is maintained without tillage despite clear benefits to soil nutrient levels, and a decrease in nutrient runoff-both of which have ecosystem-level effects and both direct and indirect effects on humans and other organisms.

4.
J Toxicol Pathol ; 26(1): 67-72, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23723571

ABSTRACT

The present report describes a rare case of spontaneous tumor of the salivary gland in a male Sprague-Dawley rat. The clinically confirmed mass rapidly developed in the cervical region between 19 and 21 weeks of age, and the animal was subsequently euthanized. At necropsy, a well-circumscribed nodule approximately 7 × 6 cm in diameter was found at the site of the salivary gland. The cut surface of the nodule was lobulated and soft and had a pinkish tan fish-flesh appearance. One large cyst (approximately 3 × 2 cm in size) containing reddish fluid was also present in the nodule. Histopathologically, the tumor, with a partially lobulated structure, was surrounded by a thin fibrous capsule. The majority of tumor cells formed a diffuse solid sheet structure that mainly consisted of small ovoid or spindle-shaped cells. In the tumor periphery, some cells were arranged in nest-like structures. Small duct-like structures lined with a monolayer of cuboidal epithelial cells resembling an intercalated duct or large polygonal clear cells with a myoepithelial component were also observed. Mitotic figures and necrotic foci were frequently observed in solid areas. Immunohistochemically, the tumor cells were positive for cytokeratin, epithelial membrane antigen, vimentin, p63, α-smooth muscle actin and calponin. The cells were negative for calcitonin, synaptophysin and chromogranin A. On the basis of these findings, the tumor was diagnosed as an epithelial-myoepithelial carcinoma originating from the luminal epithelial cells and myoepithelial cells in the submandibular gland.

6.
J Med Pract Manage ; 24(6): 350-4, 2009.
Article in English | MEDLINE | ID: mdl-19663359

ABSTRACT

The troubled economy and a new administration in Washington have reinvigorated the debate over the merits of disease management programs and the savings they bring to healthcare. At the forefront of the discussion are physicians who are discovering disease management's innovative approach to treating the chronically ill. Across the country, physicians are responding to evidence-based programs designed to improve patient outcomes that, at the same time, assist them in reaching pay-for-performance goals. New research shows that when disease management professionals provide physicians with credible information, course corrections are made more than 85% of the time.


Subject(s)
Disease Management , Outcome Assessment, Health Care/economics , Physician Incentive Plans/economics , Physicians/economics , Humans , Treatment Outcome , United States
7.
J Med Pract Manage ; 23(6): 332-5, 2008.
Article in English | MEDLINE | ID: mdl-18615996

ABSTRACT

Disease management is relatively new, and many medical practices have misconceptions about how it works. Far from being a burden to busy medical practices, disease management programs can reduce hassles for physicians and office managers by coaching patients to be more compliant, better prepared, and less likely to make unnecessary phone calls. Disease management programs cost the medical practices nothing. They can even help practices make money by providing data needed for bonuses from the growing number of pay-for-performance programs.


Subject(s)
Disease Management , Physician Incentive Plans/economics , Reimbursement, Incentive/economics , Chronic Disease , Humans , Practice Management, Medical/economics , Salaries and Fringe Benefits
8.
IEEE Trans Neural Netw ; 19(1): 168-82, 2008 Jan.
Article in English | MEDLINE | ID: mdl-18269948

ABSTRACT

In this paper, we present a novel network to separate mixtures of inputs that have been previously learned. A significant capability of the network is that it segments the components of each input object that most contribute to its classification. The network consists of amplitude-phase units that can synchronize their dynamics, so that separation is determined by the amplitude of units in an output layer, and segmentation by phase similarity between input and output layer units. Learning is unsupervised and based on a Hebbian update, and the architecture is very simple. Moreover, efficient segmentation can be achieved even when there is considerable superposition of the inputs. The network dynamics are derived from an objective function that rewards sparse coding in the generalized amplitude-phase variables. We argue that this objective function can provide a possible formal interpretation of the binding problem and that the implementation of the network architecture and dynamics is biologically plausible.


Subject(s)
Artificial Intelligence , Learning/physiology , Neural Networks, Computer , Nonlinear Dynamics , Humans , Nerve Net , Pattern Recognition, Automated
10.
JAMA ; 293(20): 2496-500, 2005 May 25.
Article in English | MEDLINE | ID: mdl-15914750

ABSTRACT

CONTEXT: Infection with Epstein-Barr virus (EBV) has been associated with an increased risk of multiple sclerosis (MS), but the temporal relationship remains unclear. OBJECTIVE: To determine whether antibodies to EBV are elevated before the onset of MS. DESIGN, SETTING, AND PARTICIPANTS: Nested case-control study conducted among more than 3 million US military personnel with blood samples collected between 1988 and 2000 and stored in the Department of Defense Serum Repository. Cases were identified as individuals granted temporary or permanent disability because of MS. For each case (n = 83), 2 controls matched by age, sex, race/ethnicity, and dates of blood sample collection were selected. Serial samples collected before the onset of symptoms were available for 69 matched case-control sets. MAIN OUTCOME MEASURES: Antibodies including IgA against EBV viral capsid antigen (VCA), and IgG against VCA, nuclear antigens (EBNA complex, EBNA-1, and EBNA-2), diffuse and restricted early antigens, and cytomegalovirus. RESULTS: The average time between blood collection and MS onset was 4 years (range, <1-11 years). The strongest predictors of MS were serum levels of IgG antibodies to EBNA complex or EBNA-1. Among individuals who developed MS, serum antibody titers to EBNA complex were similar to those of controls before the age of 20 years (geometric mean titers: cases = 245, controls = 265), but 2- to 3-fold higher at age 25 years and older (cases = 684, controls = 282; P<.001). The risk of MS increased with these antibody titers; the relative risk (RR) in persons with EBNA complex titers of at least 1280 compared with those with titers less than 80 was 9.4 (95% confidence interval [CI], 2.5-35.4; P for trend <.001). In longitudinal analyses, a 4-fold increase in anti-EBNA complex or anti-EBNA-1 titers during the follow-up was associated with a 3-fold increase in MS risk (EBNA complex: RR , 3.0; 95% CI, 1.3-6.5; EBNA-1: RR, 3.0; 95% CI, 1.2-7.3). No association was found between cytomegalovirus antibodies and MS. CONCLUSION: These results suggest an age-dependent relationship between EBV infection and development of MS.


Subject(s)
Antibodies, Viral/blood , Epstein-Barr Virus Infections/immunology , Herpesvirus 4, Human/immunology , Multiple Sclerosis/virology , Adult , Case-Control Studies , Epstein-Barr Virus Infections/physiopathology , Epstein-Barr Virus Nuclear Antigens/immunology , Female , Humans , Immunoglobulin A/blood , Immunoglobulin G/blood , Longitudinal Studies , Male , Military Personnel , Multiple Sclerosis/blood , Multiple Sclerosis/physiopathology , Risk Factors , United States
11.
JAMA ; 289(12): 1533-6, 2003 Mar 26.
Article in English | MEDLINE | ID: mdl-12672770

ABSTRACT

CONTEXT: Infection with Epstein-Barr virus (EBV) has been associated with an increased risk of multiple sclerosis (MS), but the temporal relationship remains unclear. OBJECTIVE: To determine whether antibodies to EBV are elevated before the onset of MS. DESIGN, SETTING, AND POPULATION: Nested case-control study conducted among more than 3 million US military personnel with blood samples collected between 1988 and 2000 and stored in the Department of Defense Serum Repository. Cases were identified as individuals granted temporary or permanent disability because of MS. For each case (n = 83), 2 controls matched by age, sex, race/ethnicity, and dates of blood sample collection were selected. MAIN OUTCOME MEASURES: Antibodies including IgA against EBV viral capsid antigen (VCA) and IgG against VCA, nuclear antigens (EBNA complex, EBNA-1, and EBNA-2), diffuse and restricted early antigens, and cytomegalovirus. RESULTS: The average time between blood collection and MS onset was 4 years. The strongest predictors of MS were serum levels of IgG antibodies to VCA or EBNA complex. The risk of MS increased monotonically with these antibody titers; relative risk (RR) in persons in the highest category of VCA (> or =2560) compared with those in the lowest (< or =160) was 19.7 (95% confidence interval [CI], 2.2-174; P for trend =.004). For EBNA complex titers, the RR for those in the highest category (> or =1280) was 33.9 (95% CI, 4.1-283; P for trend <.001) vs those in the lowest category (< or =40). Similarly strong positive associations between EBV antibodies and risk of MS were already present in samples collected 5 or more years before MS onset. No association was found between cytomegalovirus antibodies and MS. CONCLUSION: These results suggest a relationship between EBV infection and development of MS.


Subject(s)
Antibodies, Viral/blood , Epstein-Barr Virus Infections/physiopathology , Herpesvirus 4, Human/immunology , Multiple Sclerosis/virology , Adolescent , Adult , Antigens, Viral/immunology , Capsid Proteins/immunology , Case-Control Studies , Cytomegalovirus/immunology , Epstein-Barr Virus Nuclear Antigens/immunology , Female , Humans , Immunoglobulin A/immunology , Immunoglobulin G/immunology , Male , Multiple Sclerosis/immunology
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