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1.
Citiz Sci ; 7(1)2022.
Article in English | MEDLINE | ID: mdl-36909292

ABSTRACT

Disaster research faces significant infrastructure challenges: regional and federal coordination, access to resources, and community collaboration. Disasters can lead to chemical exposures that potentially impact human health and cause concern in affected communities. Community-engaged research, which incorporates local knowledge and voices, is well-suited for work with communities that experience impacts of environmental exposures following disasters. We present three examples of community-engaged disaster research (CEnDR) following oil spills, hurricanes, and wildfires, and their impact on long-term social, physical, and technical community infrastructure. We highlight the following CEnDR structures: researcher/community networks; convenient research tools; adaptable data collection modalities for equitable access; and return of data.

2.
Aquat Toxicol ; 235: 105810, 2021 Jun.
Article in English | MEDLINE | ID: mdl-33823483

ABSTRACT

There is a growing awareness that transient, sublethal embryonic exposure to crude oils cause subtle but important forms of delayed toxicity in fish. While the precise mechanisms for this loss of individual fitness are not well understood, they involve the disruption of early cardiogenesis and a subsequent pathological remodeling of the heart much later in juveniles. This developmental cardiotoxicity is attributable, in turn, to the inhibitory actions of crude oil-derived mixtures of polycyclic aromatic compounds (PACs) on specific ion channels and other proteins that collectively drive the rhythmic contractions of heart muscle cells via excitation-contraction coupling. Here we exposed Pacific herring (Clupea pallasi) embryos to oiled gravel effluent yielding ΣPAC concentrations as low as ~ 1 µg/L (64 ng/g in tissues). Upon hatching in clean seawater, and following the depuration of tissue PACs (as evidenced by basal levels of cyp1a gene expression), the ventricles of larval herring hearts showed a concentration-dependent reduction in posterior growth (ballooning). This was followed weeks later in feeding larvae by abnormal trabeculation, or formation of the finger-like projections of interior spongy myocardium, and months later with hypertrophy (overgrowth) of the spongy myocardium in early juveniles. Given that heart muscle cell differentiation and migration are driven by Ca2+-dependent intracellular signaling, the observed disruption of ventricular morphogenesis was likely a secondary (downstream) consequence of reduced calcium cycling and contractility in embryonic cardiomyocytes. We propose defective trabeculation as a promising phenotypic anchor for novel morphometric indicators of latent cardiac injury in oil-exposed herring, including an abnormal persistence of cardiac jelly in the ventricle wall and cardiomyocyte hyperproliferation. At a corresponding molecular level, quantitative expression assays in the present study also support biomarker roles for genes known to be involved in muscle contractility (atp2a2, myl7, myh7), cardiomyocyte precursor fate (nkx2.5) and ventricular trabeculation (nrg2, and hbegfa). Overall, our findings reinforce both proximal and indirect roles for dysregulated intracellular calcium cycling in the canonical fish early life stage crude oil toxicity syndrome. More work on Ca2+-mediated cellular dynamics and transcription in developing cardiomyocytes is needed. Nevertheless, the highly specific actions of ΣPAC mixtures on the heart at low, parts-per-billion tissue concentrations directly contravene classical assumptions of baseline (i.e., non-specific) crude oil toxicity.


Subject(s)
Petroleum/toxicity , Water Pollutants, Chemical/toxicity , Animals , Cardiotoxicity/pathology , Embryo, Nonmammalian/drug effects , Embryo, Nonmammalian/pathology , Fishes/embryology , Fishes/physiology , Heart , Larva , Myocardium/chemistry , Petroleum Pollution , Polycyclic Aromatic Hydrocarbons/toxicity , Seawater
3.
iScience ; 19: 1101-1113, 2019 Sep 27.
Article in English | MEDLINE | ID: mdl-31536959

ABSTRACT

As Arctic ice recedes, future oil spills pose increasing risk to keystone species and the ecosystems they support. We show that Polar cod (Boreogadus saida), an energy-rich forage fish for marine mammals, seabirds, and other fish, are highly sensitive to developmental impacts of crude oil. Transient oil exposures ≥300 µg/L during mid-organogenesis disrupted the normal patterning of the jaw as well as the formation and function of the heart, in a manner expected to be lethal to post-hatch larvae. More importantly, we found that exposure to lower levels of oil caused a dysregulation of lipid metabolism and growth that persisted in morphologically normal juveniles. As lipid content is critical for overwinter survival and recruitment, we anticipate Polar cod losses following Arctic oil spills as a consequence of both near-term and delayed mortality. These losses will likely influence energy flow within Arctic food webs in ways that are as-yet poorly understood.

4.
Echocardiography ; 33(10): 1546-1556, 2016 Oct.
Article in English | MEDLINE | ID: mdl-27783876

ABSTRACT

BACKGROUND: The anatomical substrate for the mid-mural ventricular hyperechogenic zone remains uncertain, but it may represent no more than ultrasound reflected from cardiomyocytes orientated orthogonally to the ultrasonic beam. We sought to ascertain the relationship between the echogenic zone and the orientation of the cardiomyocytes. METHODS: We used 3D echocardiography, diffusion tensor imaging, and microcomputed tomography to analyze the location and orientation of cardiomyocytes within the echogenic zone. RESULTS: We demonstrated that visualization of the echogenic zone is dependent on the position of the transducer and is most clearly seen from the apical window. Diffusion tensor imaging and microcomputed tomography show that the echogenic zone seen from the apical window corresponds to the position of the circumferentially orientated cardiomyocytes. An oblique band seen in the parasternal view relates to cardiomyocytes orientated orthogonally to the ultrasonic beam. CONCLUSIONS: The mid-mural ventricular hyperechogenic zone represents reflected ultrasound from cardiomyocytes aligned orthogonal to the ultrasonic beam. The echogenic zone does not represent a space, a connective tissue sheet, a boundary between ascending and descending limbs of a hypothetical helical ventricular myocardial band, nor an abrupt change in cardiomyocyte orientation.


Subject(s)
Echocardiography/methods , Heart Ventricles/cytology , Heart Ventricles/diagnostic imaging , Magnetic Resonance Imaging/methods , Myocytes, Cardiac/cytology , Tomography, X-Ray Computed/methods , Aged , Cardiac Imaging Techniques/methods , Female , Humans
5.
Environ Sci Technol ; 50(14): 7489-97, 2016 07 19.
Article in English | MEDLINE | ID: mdl-27391856

ABSTRACT

Passive sampling devices were used to measure air vapor and water dissolved phase concentrations of 33 polycyclic aromatic hydrocarbons (PAHs) and 22 oxygenated PAHs (OPAHs) at four Gulf of Mexico coastal sites prior to, during and after shoreline oiling from the Deepwater Horizon oil spill (DWH). Measurements were taken at each site over a 13 month period, and flux across the water-air boundary was determined. This is the first report of vapor phase and diffusive flux of both PAHs and OPAHs during the DWH. Vapor phase sum PAH and OPAH concentrations ranged between 6.6 and 210 ng/m(3) and 0.02 and 34 ng/m(3) respectively. PAH and OPAH concentrations in air exhibited different spatial and temporal trends than in water, and air-water flux of 13 individual PAHs was shown to be at least partially influenced by the DWH incident. The largest PAH volatilizations occurred at the sites in Alabama and Mississippi at nominal rates of 56 000 and 42 000 ng/m(2) day(-1) in the summer. Naphthalene was the PAH with the highest observed volatilization rate of 52 000 ng/m(2) day(-1) in June 2010. This work represents additional evidence of the DWH incident contributing to air contamination, and provides one of the first quantitative air-water chemical flux determinations with passive sampling technology.


Subject(s)
Environmental Monitoring , Water Pollutants, Chemical , Petroleum Pollution , Polycyclic Aromatic Hydrocarbons , Water
7.
Cult Health Sex ; 17(7): 825-41, 2015.
Article in English | MEDLINE | ID: mdl-25686777

ABSTRACT

Using a socio-ecological, structural determinants framework, this study assesses the impact of municipal licensing policies and related policing practices across the Greater Vancouver Area (Canada) on the risk of violence within indoor sex work venues. Qualitative interviews were conducted with 46 migrant/immigrant sex workers, managers and owners of licensed indoor sex work establishments and micro-brothels. Findings indicate that policing practices and licensing requirements increase sex workers' risk of violence and conflict with clients and result in heightened stress, an inability to rely on police support, lost income and the displacement of sex workers to more hidden informal work venues. Prohibitive licensing and policing practices prevent sex workers, managers and owners from adopting safer workplace measures and exacerbate health and safety risks for sex workers. This study provides critical evidence of the negative public health implications of prohibitive municipal licensing in the context of a criminalised and enforcement-based approach to sex work. Workplace safety recommendations include the decriminalisation of sex work and the elimination of disproportionately high fees for licences, criminal record restrictions, door lock restrictions, employee registration requirements and the use of police as licensing inspectors.


Subject(s)
Risk Reduction Behavior , Sex Offenses/statistics & numerical data , Sex Workers/statistics & numerical data , Transients and Migrants/statistics & numerical data , Violence/prevention & control , Adult , British Columbia , Female , Humans , Male , Women's Rights/standards , Young Adult
8.
Environ Sci Technol ; 49(1): 141-9, 2015 Jan 06.
Article in English | MEDLINE | ID: mdl-25412353

ABSTRACT

Passive sampling devices were used to measure air vapor and water dissolved phase concentrations of 33 polycyclic aromatic hydrocarbons (PAHs) and 22 oxygenated PAHs (OPAHs) at four Gulf of Mexico coastal sites prior to, during, and after shoreline oiling from the Deepwater Horizon oil spill (DWH). Measurements were taken at each site over a 13 month period, and flux across the water-air boundary was determined. This is the first report of vapor phase and flux of both PAHs and OPAHs during the DWH. Vapor phase sum PAH and OPAH concentrations ranged between 1 and 24 ng/m(3) and 0.3 and 27 ng/m(3), respectively. PAH and OPAH concentrations in air exhibited different spatial and temporal trends than in water, and air-water flux of 13 individual PAHs were strongly associated with the DWH incident. The largest PAH volatilizations occurred at the sites in Alabama and Mississippi in the summer, each nominally 10,000 ng/m(2)/day. Acenaphthene was the PAH with the highest observed volatilization rate of 6800 ng/m(2)/day in September 2010. This work represents additional evidence of the DWH incident contributing to air contamination, and provides one of the first quantitative air-water chemical flux determinations with passive sampling technology.


Subject(s)
Air Pollutants/analysis , Petroleum Pollution/analysis , Polycyclic Aromatic Hydrocarbons/analysis , Water Pollutants, Chemical/analysis , Air Pollutants/chemistry , Alabama , Environmental Monitoring , Mississippi , Oxygen/chemistry , Polycyclic Aromatic Hydrocarbons/chemistry , Seasons , Southeastern United States , Volatilization , Water , Water Pollutants, Chemical/chemistry
9.
Environ Pollut ; 193: 71-78, 2014 Oct.
Article in English | MEDLINE | ID: mdl-25009960

ABSTRACT

Sequestering semi-polar compounds can be difficult with low-density polyethylene (LDPE), but those pollutants may be more efficiently absorbed using silicone. In this work, optimized methods for cleaning, infusing reference standards, and polymer extraction are reported along with field comparisons of several silicone materials for polycyclic aromatic hydrocarbons (PAHs) and pesticides. In a final field demonstration, the most optimal silicone material is coupled with LDPE in a large-scale study to examine PAHs in addition to oxygenated-PAHs (OPAHs) at a Superfund site. OPAHs exemplify a sensitive range of chemical properties to compare polymers (log Kow 0.2-5.3), and transformation products of commonly studied parent PAHs. On average, while polymer concentrations differed nearly 7-fold, water-calculated values were more similar (about 3.5-fold or less) for both PAHs (17) and OPAHs (7). Individual water concentrations of OPAHs differed dramatically between silicone and LDPE, highlighting the advantages of choosing appropriate polymers and optimized methods for pollutant monitoring.


Subject(s)
Environmental Monitoring/instrumentation , Polycyclic Aromatic Hydrocarbons/analysis , Polyethylene/chemistry , Silicones/chemistry , Water Pollutants, Chemical/analysis
10.
Environ Toxicol Chem ; 33(1): 177-81, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24123227

ABSTRACT

The authors investigated coupling passive sampling technologies with ultraviolet irradiation experiments to study polycyclic aromatic hydrocarbon (PAH) and oxygenated PAH transformation processes in real-world bioavailable mixtures. Passive sampling device (PSD) extracts were obtained from coastal waters impacted by the Deepwater Horizon oil spill and Superfund sites in Portland, Oregon, USA. Oxygenated PAHs were found in the contaminated waters with our PSDs. All mixtures were subsequently exposed to a mild dose of ultraviolet B (UVB). A reduction in PAH levels and simultaneous formation of several oxygenated PAHs were measured. Site-specific differences were observed with UVB-exposed PSD mixtures.


Subject(s)
Environmental Monitoring/methods , Polycyclic Aromatic Hydrocarbons/analysis , Ultraviolet Rays , Water Pollutants, Chemical/analysis , Environmental Monitoring/instrumentation , Gulf of Mexico , Oregon , Oxygen/chemistry , Petroleum Pollution , Photolysis , Polycyclic Aromatic Hydrocarbons/chemistry , Polycyclic Aromatic Hydrocarbons/radiation effects , Water Pollutants, Chemical/chemistry , Water Pollutants, Chemical/radiation effects
12.
Environ Toxicol Chem ; 31(12): 2877-87, 2012 Dec.
Article in English | MEDLINE | ID: mdl-23001962

ABSTRACT

Biological Response Indicator Devices Gauging Environmental Stressors (BRIDGES) is a bioanalytical tool that combines passive sampling with the embryonic zebrafish developmental toxicity bioassay to provide a quantitative measure of the toxicity of bioavailable complex mixtures. Passive sampling devices (PSDs), which sequester and concentrate bioavailable organic contaminants from the environment, were deployed in the Willamette and Columbia Rivers within and outside of the Portland Harbor Superfund site in Portland, OR, USA. Six sampling events were conducted in the summer and fall of 2009 and 2010. Passive sampling device extracts were analyzed for polycyclic aromatic hydrocarbon (PAH) compounds and screened for 1,201 chemicals of concern using deconvolution-reporting software. The developmental toxicity of the extracts was analyzed using the embryonic zebrafish bioassay. The BRIDGES tool provided site-specific, temporally resolved information about environmental contaminant mixtures and their toxicity. Multivariate modeling approaches were applied to paired chemical and toxic effects data sets to help unravel chemistry-toxicity associations. Modeling elucidated spatial and temporal trends in PAH concentrations and the toxicity of the samples and identified a subset of PAH analytes that were the most highly correlated with observed toxicity. Although the present study highlights the complexity of discerning specific bioactive compounds in complex mixtures, it demonstrates methods for associating toxic effects with chemical characteristics of environmental samples.


Subject(s)
Environmental Monitoring/methods , Water Pollutants, Chemical/toxicity , Biological Assay , Environmental Monitoring/instrumentation , Polycyclic Aromatic Hydrocarbons/analysis , Polycyclic Aromatic Hydrocarbons/toxicity , Rivers/chemistry , Water Pollutants, Chemical/analysis
13.
Environ Toxicol Chem ; 31(12): 2888-92, 2012 Dec.
Article in English | MEDLINE | ID: mdl-22997050

ABSTRACT

The use of passive sampling devices (PSDs) for monitoring hydrophobic organic contaminants in aquatic environments can entail logistical constraints that often limit a comprehensive statistical sampling plan, thus resulting in a restricted number of samples. The present study demonstrates an approach for using the results of a pilot study designed to estimate sampling variability, which in turn can be used as variance estimates for confidence intervals for future n = 1 PSD samples of the same aquatic system. Sets of three to five PSDs were deployed in the Portland Harbor Superfund site for three sampling periods over the course of two years. The PSD filters were extracted and, as a composite sample, analyzed for 33 polycyclic aromatic hydrocarbon compounds. The between-sample and within-sample variances were calculated to characterize sources of variability in the environment and sampling methodology. A method for calculating a statistically reliable and defensible confidence interval for the mean of a single aquatic passive sampler observation (i.e., n = 1) using an estimate of sample variance derived from a pilot study is presented. Coverage probabilities are explored over a range of variance values using a Monte Carlo simulation.


Subject(s)
Environmental Monitoring/methods , Polycyclic Aromatic Hydrocarbons/analysis , Water Pollutants, Chemical/analysis , Water Pollution, Chemical/statistics & numerical data , Confidence Intervals , Environmental Monitoring/instrumentation , Hydrophobic and Hydrophilic Interactions , Pilot Projects , Polycyclic Aromatic Hydrocarbons/chemistry , Water Pollutants, Chemical/chemistry
15.
Environ Sci Technol ; 46(4): 2033-9, 2012 Feb 21.
Article in English | MEDLINE | ID: mdl-22321043

ABSTRACT

An estimated 4.1 million barrels of oil and 2.1 million gallons of dispersants were released into the Gulf of Mexico during the Deepwater Horizon oil spill. There is a continued need for information about the impacts and long-term effects of the disaster on the Gulf of Mexico. The objectives of this study were to assess bioavailable polycyclic aromatic hydrocarbons (PAHs) in the coastal waters of four Gulf Coast states that were impacted by the spill. For over a year, beginning in May 2010, passive sampling devices were used to monitor the bioavailable concentration of PAHs. Prior to shoreline oiling, baseline data were obtained at all the study sites, allowing for direct before and after comparisons of PAH contamination. Significant increases in bioavailable PAHs were seen following the oil spill, however, preoiling levels were observed at all sites by March 2011. A return to elevated PAH concentrations, accompanied by a chemical fingerprint similar to that observed while the site was being impacted by the spill, was observed in Alabama in summer 2011. Chemical forensic modeling demonstrated that elevated PAH concentrations are associated with distinctive chemical profiles.


Subject(s)
Petroleum Pollution , Polycyclic Aromatic Hydrocarbons/analysis , Water Pollutants, Chemical/analysis , Environmental Monitoring , Gulf of Mexico
16.
Chemosphere ; 85(6): 920-7, 2011 Oct.
Article in English | MEDLINE | ID: mdl-21741671

ABSTRACT

Passive sampling devices (PSDs) sequester the freely dissolved fraction of lipophilic contaminants, mimicking passive chemical uptake and accumulation by biomembranes and lipid tissues. Public Health Assessments that inform the public about health risks from exposure to contaminants through consumption of resident fish are generally based on tissue data, which can be difficult to obtain and requires destructive sampling. The purpose of this study is to apply PSD data in a Public Health Assessment to demonstrate that PSDs can be used as a biological surrogate to evaluate potential human health risks and elucidate spatio-temporal variations in risk. PSDs were used to measure polycyclic aromatic hydrocarbons (PAHs) in the Willamette River; upriver, downriver and within the Portland Harbor Superfund megasite for 3 years during wet and dry seasons. Based on an existing Public Health Assessment for this area, concentrations of PAHs in PSDs were substituted for fish tissue concentrations. PSD measured PAH concentrations captured the magnitude, range and variability of PAH concentrations reported for fish/shellfish from Portland Harbor. Using PSD results in place of fish data revealed an unacceptable risk level for cancer in all seasons but no unacceptable risk for non-cancer endpoints. Estimated cancer risk varied by several orders of magnitude based on season and location. Sites near coal tar contamination demonstrated the highest risk, particularly during the dry season and remediation activities. Incorporating PSD data into Public Health Assessments provides specific spatial and temporal contaminant exposure information that can assist public health professionals in evaluating human health risks.


Subject(s)
Environmental Monitoring/instrumentation , Models, Statistical , Polycyclic Aromatic Hydrocarbons/analysis , Polycyclic Aromatic Hydrocarbons/toxicity , Public Health/statistics & numerical data , Risk Assessment/methods , Rivers/chemistry , Animals , Fishes , Humans , Neoplasms/chemically induced , Oregon , Time Factors , Water Pollutants, Chemical/analysis , Water Pollutants, Chemical/toxicity
17.
J Allergy Clin Immunol ; 126(6): 1242-51, 2010 Dec.
Article in English | MEDLINE | ID: mdl-21036387

ABSTRACT

BACKGROUND: Immune dysregulation, polyendocrinopathy, enteropathy, X-linked (IPEX) is a primary immunodeficiency with autoimmunity caused by mutations in forkhead box P3 (FOXP3), which encodes a transcription factor involved in regulatory T (Treg) cell function. The mechanistic basis for how different mutations in FOXP3 cause distinct manifestations of IPEX remains unclear. OBJECTIVE: To determine whether 3 different point mutants of FOXP3 that cause severe or mild IPEX differ in their ability to reprogram conventional T cells into Treg cells. METHODS: Human CD4(+) T cells were transduced with wild-type or point mutant forms of FOXP3, and changes in cell surface marker expression, cytokine production, proliferation and suppressive capacity were assessed. Ex vivo T(H)17 cells were also transduced with different forms of FOXP3 to monitor changes in IL-17 production. RESULTS: The forkhead mutant F373A failed to upregulate CD25 and CCR4, did not suppress cytokine production, and induced suppressive activity less effectively than wild-type FOXP3. In contrast, although the forkhead mutant R347H was also defective in upregulation of CD25, it suppressed the production of cytokines, conferred suppressive capacity on CD4(+) T cells, and suppressed IL-17 production. F324L, a mutant outside the forkhead domain associated with mild IPEX, was equivalent to wild-type FOXP3 in all aspects tested. CONCLUSION: Mutations in FOXP3 that cause IPEX do not uniformly abrogate the ability of FOXP3 to regulate transcription and drive the development of Treg cells. These data support the notion that factors in addition to functional changes in Treg cells, such as alterations in conventional T cells, are involved in the pathogenesis of IPEX.


Subject(s)
Forkhead Transcription Factors/metabolism , Immunologic Deficiency Syndromes/genetics , Mutant Proteins/metabolism , T-Lymphocyte Subsets/metabolism , T-Lymphocytes, Regulatory/metabolism , Adolescent , CD4 Antigens/biosynthesis , Cell Proliferation , Cell Transdifferentiation/genetics , Cells, Cultured , Child , Cytokines/genetics , Cytokines/metabolism , Forkhead Transcription Factors/genetics , Forkhead Transcription Factors/immunology , Humans , Immunologic Deficiency Syndromes/immunology , Immunologic Deficiency Syndromes/pathology , Immunologic Deficiency Syndromes/physiopathology , Immunosuppression Therapy , Mutant Proteins/genetics , Mutant Proteins/immunology , Point Mutation/genetics , Polyendocrinopathies, Autoimmune , T-Lymphocyte Subsets/immunology , T-Lymphocyte Subsets/pathology , T-Lymphocytes, Regulatory/immunology , T-Lymphocytes, Regulatory/pathology , Transgenes/genetics , Young Adult
18.
Wound Repair Regen ; 18(6): 614-23, 2010.
Article in English | MEDLINE | ID: mdl-20955343

ABSTRACT

Engineered skin substitutes (ESSs) comprising both keratinocytes and fibroblasts can afford many advantages over the use of autologous keratinocyte grafts for the treatment of full-thickness and partial-thickness burns. In this study, we investigated the efficacy of a novel ESS containing both genetically altered fibroblasts that express the immunosuppressive factor indoleamine 2,3-dioxygenase (IDO) and primary keratinocytes from a nonautologous source to confer immune protection of xenogeneic cells cultured in a bilayer ESS. The results show that engraftment of IDO expressing skin substitutes on the back of rats significantly improves healing progression over 7 days compared with both nontreated and non-IDO-expressing skin substitutes (p<0.001). Immuno-staining of CD3 and CD31 suggests that IDO-expressing skin substitutes significantly suppress T cell infiltration (p<0.001) and improve neovascularization by four-fold (12.6±1.2 vs. 3.0±1.0 vessel-like structure/high power field), respectively. In conclusion, we found that IDO expression can improve the efficacy of nonautologous ESS for the purpose of wound healing by mitigating T-cell infiltration as well as promoting vascularization of the graft.


Subject(s)
Fibroblasts/metabolism , Graft Rejection/immunology , Immunosuppressive Agents/metabolism , Indoleamine-Pyrrole 2,3,-Dioxygenase/metabolism , Skin, Artificial , T-Lymphocytes/metabolism , Adenoviridae/genetics , Animals , Cell Proliferation , Cells, Cultured , Genetic Vectors , Immunosuppressive Agents/pharmacology , Indoleamine-Pyrrole 2,3,-Dioxygenase/pharmacology , Neovascularization, Physiologic , Rats , Rats, Sprague-Dawley , Tissue Engineering , Transfection , Wound Healing
19.
Micron ; 41(6): 633-40, 2010 Aug.
Article in English | MEDLINE | ID: mdl-20392647

ABSTRACT

In the realm of multi-dimensional confocal microscopy, colocalization analysis of fluorescent emission signals has proven to be an invaluable tool for detecting molecular interactions between biological macromolecules at the subcellular level. We show here that image processing operations such as the deconvolution and chromatic corrections play a crucial role in the accurate determination of colocalization between biological macromolecules particularly when the fluorescent signals are faint, and when the fluorescent signals are in the blue and red emission regions. The cellular system presented here describes quantification of an activated forkhead box P3 (FOXP3) transcription factor in three-dimensional (3D) cellular space. 293T cells transfected with a conditionally active form of FOXP3 were stained for anti-FOXP3 conjugated to a fluorescent red dye (Phycoerythrin), and counterstained for DNA (nucleus) with fluorescent blue dye (Hoechst). Due to the broad emission spectra of these dyes, the fluorescent signals were collected only from peak regions and were acquired sequentially. Since the PE signal was weak, a confocal pinhole size of two Airy size was used to collect the 3D image data sets. The raw images supplemented with the spectral data show the preferential association of activated FOXP3 molecules with the nucleus. However, the PE signals were found to be highly diffusive and colocalization quantification from these raw images was not possible. In order to deconvolve the 3D raw image data set, point spread functions (PSFs) of these emissions were measured. From the measured PSF, we found that chromatic shifts between the blue and red colors were quite considerable. Followed by the applications of both the axial and lateral chromatic corrections, colocalization analysis performed on the deconvolved-chromatic corrected-3D image data set showed that 98% of DNA molecules were associated with FOXP3 molecules, whereas only 66% of FOXP3 molecules were colocalized with DNA molecules. In conclusion, our studies clearly demonstrate the importance of PSF measurements, chromatic aberration corrections followed by deconvolution in the accurate determination of transcription factors in the 3D cellular space. The reported imaging and processing methods can be a practical guide for quantitative fluorescence imaging of similar cellular systems and can provide a basis for further development.


Subject(s)
Cytosol/chemistry , Image Processing, Computer-Assisted/methods , Imaging, Three-Dimensional/methods , Microscopy, Confocal/methods , Microscopy, Fluorescence/methods , Transcription Factors/analysis , Cell Line , Humans
20.
Chemosphere ; 79(1): 1-7, 2010 Mar.
Article in English | MEDLINE | ID: mdl-20172587

ABSTRACT

The Biological Response Indicator Devices Gauging Environmental Stressors (BRIDGES) bio-analytical tool was developed in response to the need for a quantitative technology for assessing the toxicity of environmentally relevant contaminant mixtures. This tool combines passive samplers with the embryonic zebrafish model. When applied in an urban river it effectively linked site specific, bioavailable contaminant mixtures to multiple biological responses. Embryonic zebrafish exposed to extracts from lipid-free passive samplers that were deployed at five locations, within and outside of the Portland Harbor Superfund Megasite, displayed different responses. Six of the eighteen biological responses observed in 941 exposed zebrafish were significantly different between sites. This demonstrates the sensitivity of the bio-analytical tool for detecting spatially distinct toxicity in aquatic systems; bridging environmental exposure to biological response.


Subject(s)
Water Pollutants, Chemical/toxicity , Zebrafish/embryology , Animals , Embryo, Nonmammalian/drug effects , Embryonic Development , Environmental Monitoring , Lipids/chemistry , Rivers/chemistry
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