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Speen AM, Murray JR, Krantz QT, Davies D, Evansky P, Harrill JA, Everett LJ, Bundy JL, Dailey LA, Hill J, Zander W, Carlsten E, Monsees M, Zavala J, Higuchi MA. Benchmark Dose Modeling Approaches for Volatile Organic Chemicals using a Novel Air-Liquid Interface In Vitro Exposure System. Toxicol Sci 2022; 188:88-107. [PMID: 35426944 DOI: 10.1093/toxsci/kfac040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Inhalation is the most relevant route of volatile organic chemical (VOC) exposure; however, due to unique challenges posed by their chemical properties and poor solubility in aqueous solutions, in vitro chemical safety testing is predominantly performed using direct application dosing/submerged exposures. To address the difficulties in screening toxic effects of VOCs, our cell culture exposure system permits cells to be exposed to multiple concentrations at air-liquid interface (ALI) in a 24-well format. ALI exposure methods permit direct chemical-to-cell interaction with the test article at physiological conditions. In the present study, BEAS-2B and primary normal human bronchial epithelial cells (pHBEC) are used to assess gene expression, cytotoxicity, and cell viability responses to a variety of volatile chemicals including acrolein, formaldehyde, 1,3-butadiene, acetaldehyde, 1-bromopropane, carbon tetrachloride, dichloromethane, and trichloroethylene. BEAS-2B cells were exposed to all the test agents, while pHBECs were only exposed to the latter four listed above. The VOC concentrations tested elicited only slight cell viability changes in both cell types. Gene expression changes were analyzed using benchmark dose (BMD) modeling. The BMD for the most sensitive gene set was within one order of magnitude of the threshold-limit value reported by the American Conference of Governmental Industrial Hygienists, and the most sensitive gene sets impacted by exposure correlate to known adverse health effects recorded in epidemiologic and in vivo exposure studies. Overall, our study outlines a novel in vitro approach for evaluating molecular-based points-of-departure in human airway epithelial cell exposure to volatile chemicals.
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Affiliation(s)
- Adam M Speen
- Oak Ridge Institute for Science and Education (ORISE), Oak Ridge, Tennessee 37830, USA
- CPHEA, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27709, USA
| | - Jessica R Murray
- CPHEA, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27709, USA
| | - Quentin Todd Krantz
- CPHEA, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27709, USA
| | - David Davies
- CPHEA, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27709, USA
| | - Paul Evansky
- CPHEA, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27709, USA
| | - Joshua A Harrill
- CCTE, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27709, USA
| | - Logan J Everett
- CCTE, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27709, USA
| | - Joseph L Bundy
- CCTE, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27709, USA
| | - Lisa A Dailey
- CPHEA, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27709, USA
| | - Jazzlyn Hill
- CPHEA, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27709, USA
- Oak Ridge Associated Universities (ORAU), Oak Ridge, Tennessee 37830, USA
| | - Wyatt Zander
- CPHEA, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27709, USA
- Oak Ridge Associated Universities (ORAU), Oak Ridge, Tennessee 37830, USA
| | - Elise Carlsten
- CPHEA, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27709, USA
- Oak Ridge Associated Universities (ORAU), Oak Ridge, Tennessee 37830, USA
| | - Michael Monsees
- CPHEA, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27709, USA
- Oak Ridge Associated Universities (ORAU), Oak Ridge, Tennessee 37830, USA
| | - Jose Zavala
- MedTec BioLab Inc., Hillsborough, North Carolina 27278, USA
| | - Mark A Higuchi
- CPHEA, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27709, USA
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Wells M, Zavala J, Akerman M, Vahanian S, Kinzler W, Chavez M, Vintzileos A. 954: Novel application assessing cervical stiffness heterogeneity. Am J Obstet Gynecol 2020. [DOI: 10.1016/j.ajog.2019.11.965] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Tong H, Zavala J, McIntosh-Kastrinsky R, Sexton KG. Cardiovascular effects of diesel exhaust inhalation: photochemically altered versus freshly emitted in mice. J Toxicol Environ Health A 2019; 82:944-955. [PMID: 31566091 PMCID: PMC7308149 DOI: 10.1080/15287394.2019.1671278] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
This study was designed to compare the cardiovascular effects of inhaled photochemically altered diesel exhaust (aged DE) to freshly emitted DE (fresh DE) in female C57Bl/6 mice. Mice were exposed to either fresh DE, aged DE, or filtered air (FA) for 4 hr using an environmental irradiation chamber. Cardiac responses were assessed 8 hr after exposure utilizing Langendorff preparation with a protocol consisting of 20 min of perfusion and 20 min of ischemia followed by 2 hr of reperfusion. Cardiac function was measured by indices of left-ventricular-developed pressure (LVDP) and contractility (dP/dt) prior to ischemia. Recovery of post-ischemic LVDP was examined on reperfusion following ischemia. Fresh DE contained 460 µg/m3 of particulate matter (PM), 0.29 ppm of nitrogen dioxide (NO2) and no ozone (O3), while aged DE consisted of 330 µg/m3 of PM, 0.23 ppm O3 and no NO2. Fresh DE significantly decreased LVDP, dP/dtmax, and dP/dtmin compared to FA. Aged DE also significantly reduced LVDP and dP/dtmax. Data demonstrated that acute inhalation to either fresh or aged DE lowered LVDP and dP/dt, with a greater fall noted with fresh DE, suggesting that the composition of DE may play a key role in DE-induced adverse cardiovascular effects in female C57Bl/6 mice.
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Affiliation(s)
- Haiyan Tong
- Environmental Public Health Division, NHEERL, US Environmental Protection Agency, Research Triangle Park, North Carolina
| | - Jose Zavala
- Department of Environmental Sciences and Engineering, Gilling’s School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Rachel McIntosh-Kastrinsky
- Department of Environmental Sciences and Engineering, Gilling’s School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Kenneth G. Sexton
- Department of Environmental Sciences and Engineering, Gilling’s School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
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Zavala J, Ledbetter AD, Morgan DS, Dailey LA, Puckett E, McCullough SD, Higuchi M. A new cell culture exposure system for studying the toxicity of volatile chemicals at the air-liquid interface. Inhal Toxicol 2018; 30:169-177. [PMID: 30086657 DOI: 10.1080/08958378.2018.1483983] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
A cell culture exposure system (CCES) was developed to expose cells established at an air-liquid interface (ALI) to volatile chemicals. We characterized the CCES by exposing indigo dye-impregnated filter inserts inside culture wells to 125 ppb ozone (O3) for 1 h at flow rates of 5 and 25 mL/min/well; the reaction of O3 with an indigo dye produces a fluorescent product. A 5-fold increase in fluorescence at 25 mL/min/well versus 5 mL/min/well was observed, suggesting higher flows were more effective. We then exposed primary human bronchial epithelial cells (HBECs) to 0.3 ppm acrolein for 2 h at 3, 5, and 25 mL/min/well and compared our results against well-established in vitro exposure chambers at the U.S. EPA's Human Studies Facility (HSF Chambers). We measured transcript changes of heme oxygenase-1 (HMOX1) and interleukin-8 (IL-8), as well as lactate dehydrogenase (LDH) release, at 0, 1, and 24 h post-exposure. Comparing responses from HSF Chambers to the CCES, differences were only observed at 1 h post-exposure for HMOX1. Here, the HSF Chamber produced a ∼6-fold increase while the CCES at 3 and 5 mL/min/well produced a ∼1.7-fold increase. Operating the CCES at 25 mL/min/well produced a ∼4.5-fold increase; slightly lower than the HSF Chamber. Our biological results, supported by our comparison against the HSF Chambers, agree with our fluorescence results, suggesting that higher flows through the CCES are more effective at delivering volatile chemicals to cells. This new CCES will be deployed to screen the toxicity of volatile chemicals in EPA's chemical inventories.
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Affiliation(s)
- Jose Zavala
- a NHEERL , U.S. Environmental Protection Agency, Research Triangle Park , NC , USA
| | - Allen D Ledbetter
- a NHEERL , U.S. Environmental Protection Agency, Research Triangle Park , NC , USA
| | - David S Morgan
- b NHEERL, U.S. Environmental Protection Agency , Chapel Hill , NC , USA
| | - Lisa A Dailey
- b NHEERL, U.S. Environmental Protection Agency , Chapel Hill , NC , USA
| | - Earl Puckett
- a NHEERL , U.S. Environmental Protection Agency, Research Triangle Park , NC , USA
| | | | - Mark Higuchi
- a NHEERL , U.S. Environmental Protection Agency, Research Triangle Park , NC , USA
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Riedel TP, DeMarini DM, Zavala J, Warren SH, Corse EW, Offenberg JH, Kleindienst TE, Lewandowski M. Mutagenic atmospheres resulting from the photooxidation of aromatic hydrocarbon and NO x mixtures. Atmos Environ (1994) 2018; 178:164-172. [PMID: 29725240 PMCID: PMC5921836 DOI: 10.1016/j.atmosenv.2018.01.052] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Although many volatile organic compounds (VOCs) are regulated to limit air pollution and the consequent health effects, the photooxidation products generally are not. Thus, we examined the mutagenicity in Salmonella TA100 of photochemical atmospheres generated in a steady-state atmospheric simulation chamber by irradiating mixtures of single aromatic VOCs, NOx, and ammonium sulfate seed aerosol in air. The 10 VOCs examined were benzene; toluene; ethylbenzene; o-, m-, and p-xylene; 1,2,4- and 1,3,5-trimethylbenzene; m-cresol; and naphthalene. Salmonella were exposed at the air-agar interface to the generated atmospheres for 1, 2, 4, 8, or 16 h. Dark-control exposures produced non-mutagenic atmospheres, illustrating that the gas-phase precursor VOCs were not mutagenic at the concentrations tested. Under irradiation, all but m-cresol and naphthalene produced mutagenic atmospheres, with potencies ranging from 2.0 (p-xylene) to 10.4 (ethylbenzene) revertants m3 mgC-1 h-1. The mutagenicity was due exclusively to direct-acting late-generation products of the photooxidation reactions. Gas-phase chemical analysis showed that a number of oxidized organic chemical species enhanced during the irradiated exposure experiments correlated (r ≥ 0.81) with the mutagenic potencies of the atmospheres. Molecular formulas assigned to these species indicated that they likely contained peroxy acid, aldehyde, alcohol, and other functionalities.
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Affiliation(s)
- Theran P. Riedel
- National Exposure Research Laboratory, United States Environmental Protection Agency, Research Triangle Park, North Carolina, United States
- Corresponding Author, Mailing address: U.S. EPA, 109 T.W. Alexander Dr, D205-3, Research Triangle Park, NC, USA 27711, , Phone: +1 919-541-0877, Fax: +1 919-541-0239
| | - David M. DeMarini
- National Health and Environmental Effects Research Laboratory, United States Environmental Protection Agency, Research Triangle Park, North Carolina, United States
| | - Jose Zavala
- Oak Ridge Institute for Science and Education, National Health and Environmental Effects Research Laboratory, United States Environmental Protection Agency, Research Triangle Park, North Carolina, United States
| | - Sarah H. Warren
- National Health and Environmental Effects Research Laboratory, United States Environmental Protection Agency, Research Triangle Park, North Carolina, United States
| | - Eric W. Corse
- Jacobs Technology, Cary, North Carolina, United States
| | - John H. Offenberg
- National Exposure Research Laboratory, United States Environmental Protection Agency, Research Triangle Park, North Carolina, United States
| | - Tadeusz E. Kleindienst
- National Exposure Research Laboratory, United States Environmental Protection Agency, Research Triangle Park, North Carolina, United States
| | - Michael Lewandowski
- National Exposure Research Laboratory, United States Environmental Protection Agency, Research Triangle Park, North Carolina, United States
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Zavala J, Krug JD, Warren SH, Krantz QT, King C, McKee J, Gavett SH, Lewandowski M, Lonneman WA, Kleindienst TE, Meier MJ, Higuchi M, Gilmour MI, DeMarini DM. Evaluation of an Air Quality Health Index for Predicting the Mutagenicity of Simulated Atmospheres. Environ Sci Technol 2018; 52:3045-3053. [PMID: 29406743 PMCID: PMC5858694 DOI: 10.1021/acs.est.8b00613] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
No study has evaluated the mutagenicity of atmospheres with a calculated air quality health index (AQHI). Thus, we generated in a UV-light-containing reaction chamber two simulated atmospheres (SAs) with similar AQHIs but different proportions of criteria pollutants and evaluated them for mutagenicity in three Salmonella strains at the air-agar interface. We continuously injected into the chamber gasoline, nitric oxide, and ammonium sulfate, as well as either α-pinene to produce SA-PM, which had a high concentration of particulate matter (PM): 119 ppb ozone (O3), 321 ppb NO2, and 1007 μg/m3 PM2.5; or isoprene to produce SA-O3, which had a high ozone (O3) concentration: 415 ppb O3, 633 ppb NO2, and 55 μg/m3 PM2.5. Neither PM2.5 extracts, NO2, or O3 alone, nor nonphoto-oxidized mixtures were mutagenic or cytotoxic. Both photo-oxidized atmospheres were largely direct-acting base-substitution mutagens with similar mutagenic potencies in TA100 and TA104. The mutagenic potencies [(revertants/h)/(mgC/m3)] of SA-PM (4.3 ± 0.4) and SA-O3 (9.5 ± 1.3) in TA100 were significantly different ( P < 0.0001), but the mutation spectra were not ( P = 0.16), being ∼54% C → T and ∼46% C → A. Thus, the AQHI may have some predictive value for the mutagenicity of the gas phase of air.
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Affiliation(s)
- Jose Zavala
- ORISE Research Fellow, National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27711, United States
| | - Jonathan D. Krug
- National Environmental Research Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27711, United States
| | - Sarah H. Warren
- National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27711, United States
| | - Q. Todd Krantz
- National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27711, United States
| | - Charly King
- National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27711, United States
| | - John McKee
- National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27711, United States
| | - Stephen H. Gavett
- National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27711, United States
| | - Michael Lewandowski
- National Environmental Research Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27711, United States
| | - William A. Lonneman
- National Environmental Research Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27711, United States
| | - Tadeusz E. Kleindienst
- National Environmental Research Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27711, United States
| | - Matthew J. Meier
- Biology Department, Carleton University, Ottawa, Ontario K1S 5B6, Canada
| | - Mark Higuchi
- National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27711, United States
| | - M. Ian Gilmour
- National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27711, United States
| | - David M. DeMarini
- National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27711, United States
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Zavala J, Fitace F, León M, Ponce F, Gutiérrez H. Resultados funcionales tras entrenamiento fisioterapéutico que incluye la realidad virtual en mayores de 60 años con artroplastia total de cadera: estudio descriptivo. ACTA ACUST UNITED AC 2017. [DOI: 10.1016/j.ft.2017.04.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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Chalker CJ, An H, Zavala J, Parija A, Banerjee S, Lutkenhaus JL, Batteas JD. Fabrication and Electrochemical Performance of Structured Mesoscale Open Shell V 2O 5 Networks. Langmuir 2017; 33:5975-5981. [PMID: 28494587 DOI: 10.1021/acs.langmuir.6b04163] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Crystalline vanadium pentoxide (V2O5) has attracted significant interest as a potential cathode material for energy storage applications due to its high theoretical capacity. Unfortunately, the material suffers from low conductivity as well as slow lithium ion diffusion, both of which affect how fast the electrode can be charged/discharged and how many times it can be cycled. Colloidal crystal templating (CCT) provides a simple approach to create well-organized 3-D nanostructures of materials, resulting in a significant increase in surface area that can lead to marked improvements in electrochemical performance. Here, a single layer of open shell V2O5 architectures ca. 1 μm in height with ca. 100 nm wall thickness was fabricated using CCT, and the electrochemical properties of these assemblies were evaluated. A decrease in polarization effects, resulting from the higher surface area mesostructured features, was found to produce significantly enhanced electrochemical performance. The discharge capacity of an unpatterned thin film of V2O5 (∼8.1 μAh/cm2) was found to increase to ∼10.2 μAh/cm2 when the material was patterned by CCT, affording enhanced charge storage capabilities as well as a decrease in the irreversible degradation during charge-discharge cycling. This work demonstrates the importance of creating mesoscale electrode surfaces for improving the performance of energy storage devices and provides fundamental understanding of the means to improve device performance.
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Affiliation(s)
- Cody J Chalker
- Department of Chemistry, ‡Artie McFerrin Department of Chemical Engineering, and §Department of Materials Science and Engineering, Texas A&M University , College Station, Texas 77843, United States
| | - Hyosung An
- Department of Chemistry, ‡Artie McFerrin Department of Chemical Engineering, and §Department of Materials Science and Engineering, Texas A&M University , College Station, Texas 77843, United States
| | - Jose Zavala
- Department of Chemistry, ‡Artie McFerrin Department of Chemical Engineering, and §Department of Materials Science and Engineering, Texas A&M University , College Station, Texas 77843, United States
| | - Abhishek Parija
- Department of Chemistry, ‡Artie McFerrin Department of Chemical Engineering, and §Department of Materials Science and Engineering, Texas A&M University , College Station, Texas 77843, United States
| | - Sarbajit Banerjee
- Department of Chemistry, ‡Artie McFerrin Department of Chemical Engineering, and §Department of Materials Science and Engineering, Texas A&M University , College Station, Texas 77843, United States
| | - Jodie L Lutkenhaus
- Department of Chemistry, ‡Artie McFerrin Department of Chemical Engineering, and §Department of Materials Science and Engineering, Texas A&M University , College Station, Texas 77843, United States
| | - James D Batteas
- Department of Chemistry, ‡Artie McFerrin Department of Chemical Engineering, and §Department of Materials Science and Engineering, Texas A&M University , College Station, Texas 77843, United States
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Zavala J, Greenan R, Krantz QT, DeMarini DM, Higuchi M, Gilmour MI, White PA. Regulating temperature and relative humidity in air-liquid interface in vitro systems eliminates cytotoxicity resulting from control air exposures. Toxicol Res (Camb) 2017; 6:448-459. [PMID: 30090513 DOI: 10.1039/c7tx00109f] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Accepted: 05/22/2017] [Indexed: 12/17/2022] Open
Abstract
VITROCELL® systems permit cell exposures at the air-liquid interface (ALI); however, there are inconsistent methodologies in the literature for their operation. Some studies find that exposure to air (vehicle control) induced cytotoxicity relative to incubator controls; others do not mention if any cytotoxicity was encountered. We sought to test whether temperature and relative humidity (temp/RH) influence cytotoxicity with an unmodified (conditions A & B) and modified (condition C) VITROCELL® 6 CF with temp/RH controls to permit conditioning of the sampled air-flow. We exposed BEAS-2B cells for 1 h to air and measured viability (WST-1 cell proliferation assay) and lactate dehydrogenase (LDH) release 6 h post-exposure. Relative to controls, cells exposed to air at (A) 22 °C and 18% RH had a 47.9% ± 3.2% (p < 0.0001) reduction in cell viability and 10.7% ± 2.0% (p < 0.0001) increase in LDH release (B) 22 °C and 55% RH had a 40.3% ± 5.8% (p < 0.0001) reduction in cell viability and 2.6% ± 2.0% (p = 0.2056) increase in LDH release, or (C) 37 °C and >75% RH showed no changes in cell viability and no increase in LDH release. Furthermore, cells exposed to air at 37 °C and >75% RH 24 h post-exposure showed no changes in viability or LDH release relative to incubator controls. Thus, reductions in cell viability were induced under conditions used typically in the literature (conditions A & B). However, our modifications (condition C) overcome this shortcoming by preventing cell desiccation; regulating temp/RH is essential for conducting adequate ALI exposures.
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Affiliation(s)
- Jose Zavala
- NHEERL , U.S. Environmental Protection Agency , Research Triangle Park , NC 27711 , USA . ; Tel: +1-919-541-2316
| | - Rebecca Greenan
- Mechanistic Studies Division , Environmental Health Science and Research Bureau , Health Canada , Ottawa , Ontario K1A 0K9 , Canada . ; ; Tel: +1-613-941-7373
| | - Q Todd Krantz
- NHEERL , U.S. Environmental Protection Agency , Research Triangle Park , NC 27711 , USA . ; Tel: +1-919-541-2316
| | - David M DeMarini
- NHEERL , U.S. Environmental Protection Agency , Research Triangle Park , NC 27711 , USA . ; Tel: +1-919-541-2316
| | - Mark Higuchi
- NHEERL , U.S. Environmental Protection Agency , Research Triangle Park , NC 27711 , USA . ; Tel: +1-919-541-2316
| | - M Ian Gilmour
- NHEERL , U.S. Environmental Protection Agency , Research Triangle Park , NC 27711 , USA . ; Tel: +1-919-541-2316
| | - Paul A White
- Mechanistic Studies Division , Environmental Health Science and Research Bureau , Health Canada , Ottawa , Ontario K1A 0K9 , Canada . ; ; Tel: +1-613-941-7373
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Zavala J, O'Brien B, Lichtveld K, Sexton KG, Rusyn I, Jaspers I, Vizuete W. Assessment of biological responses of EpiAirway 3-D cell constructs versus A549 cells for determining toxicity of ambient air pollution. Inhal Toxicol 2017; 28:251-9. [PMID: 27100558 DOI: 10.3109/08958378.2016.1157227] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
CONTEXT EpiAirway™ 3-D constructs are human-derived cell cultures of differentiated airway epithelial cells that may represent a more biologically relevant model of the human lung. However, limited information is available on their utility for exposures to air pollutants at the air-liquid interface (ALI). OBJECTIVE To assess the biological responses of EpiAirway™ cells in comparison to the responses of A549 human alveolar epithelial cells after exposure to air pollutants at ALI. METHODS Cells were exposed to filtered air, 400 ppb of ozone (O3) or a photochemically aged Synthetic Urban Mixture (SynUrb54) consisting of hydrocarbons, nitrogen oxides, O3 and other secondary oxidation products for 4 h. Basolateral supernatants and apical washes were collected at 9 and 24 h post-exposure. We assessed cytotoxicity by measuring lactate dehydrogenase (LDH) release into the culture medium and apical surface. Interleukin 6 (IL-6) and interleukin 8 (IL-8) proteins were measured in the culture medium and in the apical washes to determine the inflammatory response after exposure. RESULTS Both O3 and SynUrb54 significantly increased basolateral levels of LDH and IL-8 in A549 cells. No significant changes in LDH and IL-8 levels were observed in the EpiAirway™ cells, however, IL-6 in the apical surface was significantly elevated at 24 h after O3 exposure. CONCLUSION LDH and IL-8 are robust endpoints for assessing toxicity in A549 cells. The EpiAirway™ cells show minimal adverse effects after exposure suggesting that they are more toxicologically resistant compared to A549 cells. Higher concentrations or longer exposure times are needed to induce effects on EpiAirway™ cells.
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Affiliation(s)
- Jose Zavala
- a Department of Environmental Sciences & Engineering , University of North Carolina at Chapel Hill , Chapel Hill , NC, USA
| | - Bridget O'Brien
- a Department of Environmental Sciences & Engineering , University of North Carolina at Chapel Hill , Chapel Hill , NC, USA
| | - Kim Lichtveld
- a Department of Environmental Sciences & Engineering , University of North Carolina at Chapel Hill , Chapel Hill , NC, USA
| | - Kenneth G Sexton
- a Department of Environmental Sciences & Engineering , University of North Carolina at Chapel Hill , Chapel Hill , NC, USA
| | - Ivan Rusyn
- a Department of Environmental Sciences & Engineering , University of North Carolina at Chapel Hill , Chapel Hill , NC, USA
| | - Ilona Jaspers
- a Department of Environmental Sciences & Engineering , University of North Carolina at Chapel Hill , Chapel Hill , NC, USA .,b Department of Pediatrics , University of North Carolina at Chapel Hill , Chapel Hill , NC, USA , and.,c Center for Environmental Medicine and Lung Biology, University of North Carolina at Chapel Hill , Chapel Hill , NC, USA
| | - William Vizuete
- a Department of Environmental Sciences & Engineering , University of North Carolina at Chapel Hill , Chapel Hill , NC, USA
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Baldridge KC, Zavala J, Surratt J, Sexton KG, Contreras LM. Cellular RNA is chemically modified by exposure to air pollution mixtures. Inhal Toxicol 2015; 27:74-82. [DOI: 10.3109/08958378.2014.987361] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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Zavala J, Lichtveld K, Ebersviller S, Carson JL, Walters GW, Jaspers I, Jeffries HE, Sexton KG, Vizuete W. The Gillings Sampler--an electrostatic air sampler as an alternative method for aerosol in vitro exposure studies. Chem Biol Interact 2014; 220:158-68. [PMID: 25010910 DOI: 10.1016/j.cbi.2014.06.026] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2014] [Revised: 06/23/2014] [Accepted: 06/29/2014] [Indexed: 11/17/2022]
Abstract
There is growing interest in studying the toxicity and health risk of exposure to multi-pollutant mixtures found in ambient air, and the U.S. Environmental Protection Agency (EPA) is moving towards setting standards for these types of mixtures. Additionally, the Health Effects Institute's strategic plan aims to develop and apply next-generation multi-pollutant approaches to understanding the health effects of air pollutants. There's increasing concern that conventional in vitro exposure methods are not adequate to meet EPA's strategic plan to demonstrate a direct link between air pollution and health effects. To meet the demand for new in vitro technology that better represents direct air-to-cell inhalation exposures, a new system that exposes cells at the air-liquid interface was developed. This new system, named the Gillings Sampler, is a modified two-stage electrostatic precipitator that provides a viable environment for cultured cells. Polystyrene latex spheres were used to determine deposition efficiencies (38-45%), while microscopy and imaging techniques were used to confirm uniform particle deposition. Negative control A549 cell exposures indicated the sampler can be operated for up to 4h without inducing any significant toxic effects on cells, as measured by lactate dehydrogenase (LDH) and interleukin-8 (IL-8). A novel positive aerosol control exposure method, consisting of a p-tolualdehyde (TOLALD) impregnated mineral oil aerosol (MOA), was developed to test this system. Exposures to the toxic MOA at a 1 ng/cm(2) dose of TOLALD yielded a reproducible 1.4 and 2-fold increase in LDH and IL-8 mRNA levels over controls. This new system is intended to be used as an alternative research tool for aerosol in vitro exposure studies. While further testing and optimization is still required to produce a "commercially ready" system, it serves as a stepping-stone in the development of cost-effective in vitro technology that can be made accessible to researchers in the near future.
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Affiliation(s)
- Jose Zavala
- Department of Environmental Sciences & Engineering, University of North Carolina at Chapel Hill, United States
| | - Kim Lichtveld
- Department of Environmental Sciences & Engineering, University of North Carolina at Chapel Hill, United States
| | - Seth Ebersviller
- Department of Environmental Sciences & Engineering, University of North Carolina at Chapel Hill, United States
| | - Johnny L Carson
- Department of Pediatrics, University of North Carolina at Chapel Hill, United States; Center for Environmental Medicine and Lung Biology, University of North Carolina at Chapel Hill, United States
| | - Glenn W Walters
- Department of Environmental Sciences & Engineering, University of North Carolina at Chapel Hill, United States
| | - Ilona Jaspers
- Department of Environmental Sciences & Engineering, University of North Carolina at Chapel Hill, United States; Department of Pediatrics, University of North Carolina at Chapel Hill, United States; Center for Environmental Medicine and Lung Biology, University of North Carolina at Chapel Hill, United States
| | - Harvey E Jeffries
- Department of Environmental Sciences & Engineering, University of North Carolina at Chapel Hill, United States
| | - Kenneth G Sexton
- Department of Environmental Sciences & Engineering, University of North Carolina at Chapel Hill, United States
| | - William Vizuete
- Department of Environmental Sciences & Engineering, University of North Carolina at Chapel Hill, United States.
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Seiwert T, Adkins D, Worden F, Wade J, Hu S, Price K, Zavala J, Lussier Y, Vokes E, Cohen E. Activity of Temsirolimus Added to Cetuximab in Patients With Cetuximab-Resistant, Recurrent/Metastatic Head-and-Neck Cancer: Results of the Randomized Phase 2 Maestro-HN Study. Int J Radiat Oncol Biol Phys 2014. [DOI: 10.1016/j.ijrobp.2013.11.148] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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14
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McIntosh-Kastrinsky R, Diaz-Sanchez D, Sexton KG, Jania CM, Zavala J, Tilley SL, Jaspers I, Gilmour MI, Devlin RB, Cascio WE, Tong H. Photochemically altered air pollution mixtures and contractile parameters in isolated murine hearts before and after ischemia. Environ Health Perspect 2013; 121:1344-8. [PMID: 24148996 PMCID: PMC3855513 DOI: 10.1289/ehp.1306609] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2013] [Accepted: 10/17/2013] [Indexed: 05/16/2023]
Abstract
BACKGROUND The cardiopulmonary effects of the individual criteria air pollutants have been well investigated, but little is known about the cardiopulmonary effects of inhaled multipollutant mixtures that more realistically represent environmental exposures. OBJECTIVES We assessed the cardiopulmonary effects of exposure to photochemically altered particle-free multipollutant mixtures. METHODS We exposed mice to filtered air (FA), multipollutant mixtures, or ozone (O3) for 4 hr in a photochemical reaction chamber. Eight hours after exposure, we assessed cardiac responses using a Langendorff preparation in a protocol consisting of 20 min of global ischemia followed by 2 hr of reperfusion. Cardiac function was assessed by measuring the index of left-ventricular developed pressure (LVDP) and contractility (dP/dt) before ischemia. On reperfusion after ischemia, recovery of postischemic LVDP and size of infarct were examined. We used bronchoalveolar lavage (BAL) cell counts to assess lung inflammation. RESULTS Exposure to the multipollutant mixtures decreased LVDP, baseline rate of left ventricular contraction (dP/dtmaximum), and baseline rate of left ventricular relaxation (dP/dtminimum) compared with exposure to FA. Exposure to O3 also decreased heart rate and dP/dtminimum. Time to ischemic contracture was prolonged in the multipollutant-mixture group relative to that in the FA group. Mice in the multipollutant-mixture group had better recovery of postischemic LVDP and smaller infarct size. Exposure to multipollutant mixtures and to O3 exposure increased numbers of macrophages in the BAL fluid. CONCLUSIONS Exposure to photochemically altered urban air pollution appears to affect cardiac mechanics in isolated perfused hearts. Inhalation of acute multipollutant mixtures decreases LVDP and cardiac contractility in isolated non-ischemic murine hearts, prolongs ischemic contracture, increases postischemic recovery of LVDP, and reduces infarct size.
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Affiliation(s)
- Rachel McIntosh-Kastrinsky
- Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
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15
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Zavala J, López Jaime GR, Rodríguez Barrientos CA, Valdez-Garcia J. Corneal endothelium: developmental strategies for regeneration. Eye (Lond) 2013; 27:579-88. [PMID: 23470788 DOI: 10.1038/eye.2013.15] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The main treatment available for restoration of the corneal endothelium is keratoplasty. This procedure is faced with several difficulties, including the shortage of donor tissue, post-surgical complications associated with the use of drugs to prevent immune rejection, and a significant increase in the occurrence of glaucoma. Recently, surgical procedures such as Descemet's stripping endothelial keratoplasty have focused on the transplant of corneal endothelium, yielding better visual results but still facing the need for donor tissue. The emergent strategies in the field of cell biology and tissue cultivation of corneal endothelial cells aim at the production of transplantable endothelial cell sheets. Cell therapy focuses on the culture of corneal endothelial cells retrieved from the donor, in the donor's cornea, followed by transplantation into the recipient. Recently, research has focused on overcoming the challenge of harvesting human corneal endothelial cells and the generation of new biomembranes to be used as cell scaffolds in surgical procedures. The use of corneal endothelial precursors from the peripheral cornea has also demonstrated to be effective and represents a valuable tool for reducing the risk of rejection in allogeneic transplants. Several animal model reports also support the use of adult stem cells as therapy for corneal diseases. Current results represent important progresses in the development of new strategies based on alternative sources of tissue for the treatment of corneal endotheliopathies. Different databases were used to search literature: PubMed, Google Books, MD Consult, Google Scholar, Gene Cards, and NCBI Books. The main search terms used were: 'cornea AND embryology AND transcription factors', 'human endothelial keratoplasty AND risk factors', '(cornea OR corneal) AND (endothelium OR endothelial) AND cell culture', 'mesenchymal stem cells AND cell therapy', 'mesenchymal stem cells AND cornea', and 'stem cells AND (cornea OR corneal) AND (endothelial OR endothelium)'.
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Affiliation(s)
- J Zavala
- Ophthalmology Research Chair, Tecnologico de Monterrey, School of Medicine and Health Sciences, Monterrey, México
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Ebersviller S, Lichtveld K, Sexton KG, Zavala J, Lin YH, Jaspers I, Jeffries HE. Gaseous VOCs rapidly modify particulate matter and its biological effects - Part 1: Simple VOCs and model PM. Atmos Chem Phys Discuss 2012; 12:5065-5105. [PMID: 23457430 PMCID: PMC3583354 DOI: 10.5194/acpd-12-5065-2012] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
This is the first of a three-part study designed to demonstrate dynamic entanglements among gaseous organic compounds (VOC), particulate matter (PM), and their subsequent potential biological effects. We study these entanglements in increasingly complex VOC and PM mixtures in urban-like conditions in a large outdoor chamber. To the traditional chemical and physical characterizations of gas and PM, we added new measurements of gas-only- and PM-only-biological effects, using cultured human lung cells as model indicators. These biological effects are assessed here as increases in cellular damage or expressed irritation (i.e., cellular toxic effects) from cells exposed to chamber air relative to cells exposed to clean air. The exposure systems permit gas-only- or PM-only-exposures from the same air stream containing both gases and PM in equilibria, i.e., there are no extractive operations prior to cell exposure.Our simple experiments in this part of the study were designed to eliminate many competing atmospheric processes to reduce ambiguity in our results. Simple volatile and semi-volatile organic gases that have inherent cellular toxic properties were tested individually for biological effect in the dark (at constant humidity). Airborne mixtures were then created with each compound and PM that has no inherent cellular toxic properties for another cellular exposure. Acrolein and p-tolualdehyde were used as model VOCs and mineral oil aerosol (MOA) was selected as a surrogate for organic-containing PM. MOA is appropriately complex in composition to represent ambient PM, and it exhibits no inherent cellular toxic effects and thus did not contribute any biological detrimental effects on its own.Chemical measurements, combined with the responses of our biological exposures, clearly demonstrate that gas-phase pollutants can modify the composition of PM (and its resulting detrimental effects on lung cells) - even if the gas-phase pollutants are not considered likely to partition to the condensed phase: the VOC-modified-PM showed significantly more damage and inflammation to lung cells than did the original PM. Because gases and PM are transported and deposited differently within the atmosphere and the lungs, these results have significant consequences. For example, current US policies for research and regulation of PM do not recognize this "effect modification" phenomena (NAS, 2004).These results present an unambiguous demonstration that - even in these simple mixtures - physical and thermal interactions alone can cause a modification of the distribution of species among the phases of airborne pollution mixtures and can result in a non-toxic phase becoming toxic due to atmospheric thermal processes only. Subsequent work extends the simple results reported here to systems with photochemical transformations of complex urban mixtures and to systems with diesel exhaust produced by different fuels.
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Affiliation(s)
- S. Ebersviller
- Environmental Sciences and Engineering, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill, USA
| | - K. Lichtveld
- Environmental Sciences and Engineering, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill, USA
| | - K. G. Sexton
- Environmental Sciences and Engineering, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill, USA
| | - J. Zavala
- Environmental Sciences and Engineering, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill, USA
| | - Y-H. Lin
- Environmental Sciences and Engineering, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill, USA
| | - I. Jaspers
- Environmental Sciences and Engineering, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill, USA
- Center for Environmental Medicine and Lung Biology, Human Studies Facility, The University of North Carolina at Chapel Hill, USA
| | - H. E. Jeffries
- Environmental Sciences and Engineering, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill, USA
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Mazza CA, Zavala J, Scopel AL, Ballaré CL. Perception of solar UVB radiation by phytophagous insects: behavioral responses and ecosystem implications. Proc Natl Acad Sci U S A 1999; 96:980-5. [PMID: 9927679 PMCID: PMC15336 DOI: 10.1073/pnas.96.3.980] [Citation(s) in RCA: 97] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Most of our present knowledge about the impacts of solar UVB radiation on terrestrial ecosystems comes from studies with plants. Recently, the effects of UVB on the growth and survival of consumer species have begun to receive attention, but very little is known about UVB impacts on animal behavior. Here we report that manipulations of the flux of solar UVB received by field-grown soybean crops had large and consistent effects on the density of the thrips (Caliothrips phaseoli, Thysanoptera: Thripidae) populations that invaded the canopies, as well as on the amount of leaf damage caused by the insects. Solar UVB strongly reduced thrips herbivory. Thrips not only preferred leaves from plants that were not exposed to solar UVB over leaves from UVB-exposed plants in laboratory and field choice experiments, but they also appeared to directly sense and avoid exposure to solar UVB. Additional choice experiments showed that soybean leaf consumption by the late-season soybean worm Anticarsia gemmatalis (Lepidoptera: Noctuidae) was much less intense in leaves with even slight symptoms of an early thrips attack than in undamaged leaves. These experiments suggest that phytophagous insects can present direct and indirect behavioral responses to solar UVB. The indirect responses are mediated by changes in the plant host that are induced by UVB and, possibly, by other insects whose behavior is affected by UVB.
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Affiliation(s)
- C A Mazza
- IFEVA, (Agricultural Plant Physiology and Ecology Research Institute), Facultad de Agronomía, Universidad de Buenos Aires, Avenida San Martín 4453, 1417 Buenos Aires, Argentina
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Acosta E, Guzmán E, Puc Z, Espinoza MR, Jiménez B, Valadez N, Rosado ME, Rosales JL, Zavala J. Cloning of the cDNA for the putative t.cruzi b1-adrenergic receptor. Parasitol Int 1998. [DOI: 10.1016/s1383-5769(98)80590-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Tan Y, Zavala J, Han Q, Xu M, Sun X, Tan X, Tan X, Magana R, Geller J, Hoffman RM. Recombinant methioninase infusion reduces the biochemical endpoint of serum methionine with minimal toxicity in high-stage cancer patients. Anticancer Res 1997; 17:3857-60. [PMID: 9427792] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The tumor-specific increased minimal requirement for methionine has been shown to be a highly promising therapeutic target. To attack this target we have previously cloned the methioninase gene from Pseudomonas putida and produced recombinant methioninase (rMETase). A pilot Phase I clinical trial has been carried out to determine rMETase toxicity, rMETase pharmacokinetics, and serum MET-depletion in cancer patients. Patients with advanced breast cancer, lung cancer, renal cancer and lymphoma were given a single rMETase treatment at doses ranging from 5,000 to 20,000 units by i.v. infusion over 6-24 hours. No clinical toxicity was observed in any patient after rMETase treatment. rMETase levels reached 0.1 to 0.4 units per ml of serum in the patients which correspond to therapeutic levels in vitro. The lowest serum methionine levels in rMETase-treated patients were 0.1% of the pre-treatment levels corresponding to approximately 0.1 microM, which also correlates to therapeutic levels in vitro. The results of the rMETase pilot Phase I clinical trial therefore indicate that i.v. infusion of rMETase is safe and effectively depletes its biochemical target of serum methionine suggesting potential efficacy in future clinical trials.
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Affiliation(s)
- Y Tan
- AntiCancer, Inc., San Diego, CA 92111, USA
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Tan Y, Zavala J, Xu M, Zavala J, Hoffman RM. Serum methionine depletion without side effects by methioninase in metastatic breast cancer patients. Anticancer Res 1996; 16:3937-42. [PMID: 9042316] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The growth dependence of human tumors on elevated levels of methionine has been shown in preclinical in vitro and in vivo studies to be a frequently occurring, highly effective, tumor-selective therapeutic target. High purity endotoxin-free methioninase was produced from Pseudomonas putida in order to develop anti-methionine chemotherapy targeting of human tumors. A pilot Phase I clinical trial has been initiated in order to determine methioninase toxicity, the pharmacokinetics of methioninase and methionine-depletion and maximum tolerated dose. A two hour i.v. infusion of 5,000 units (0.4 g) and 10,000 units (0.8 g) and a ten hour i.v. infusion of 20,000 units (1.6 g) of methioninase was administered to patient-1, patient-2, and patient-3, respectively. All patients had advanced breast cancer. Blood and urine samples were obtained at frequent intervals between 0 and 24 hours. The toxicity evaluations were carried out according to FDA criteria. Pharmacokinetics data were obtained for both methioninase and methionine levels in the serum. No acute clinical toxicity was observed for all the toxicity criteria measured in patient-1, patient-2 and patient-3. The depletion of serum methionine started within 30 minutes of the infusion, and was maintained for 4 hours after the infusion was completed in patient-1 and patient-2. The lowest serum methionine levels were 35% and 19% of the pretreatment level, respectively, in patient-1 and patient-2. Patient-3 received a ten hour i.v. infusion of 20,000 units of methioninase without any signs of side effects. Patient-3 maintained serum levels of methioninase as high as 50% of the maximum level for a subsequent 6 hours after infusion. Methionine was depleted over 200-fold from 23.1 microM to 0.1 microM by the 10-hour infusion of patient-3. No clinical toxicity was observed whatsoever in all the toxicity criteria measured in patient-3. The results of the methioninase pilot Phase 1 clinical trial suggested that i.v. infusion of the methioninase is safe and effectively depletes serum methionine without any signs of side effects. Clinical studies are continuing to determine the maximum length of time complete serum methionine depletion can be tolerated.
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Affiliation(s)
- Y Tan
- AntiCancer Inc., San Diego, CA 92111, USA
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Zavala J, Sánchez L, Carillo L, Cueva A, Balbín G, Quispe V. [Atypical presentations of strongyloidiasis: a report of 8 cases]. Rev Gastroenterol Peru 1994; 14:15-21. [PMID: 8018896] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Eight clinical cases of patients with an atypical strongyloidiasis are reported. The clinical notes are reviewed, the nematode is demonstrated by serial coproparasitologic modified Baermann's method and in some cases, the parasite is found by direct test of sputum or enterotest. In all cases, the main factor has been the immunological deficiency being this nutritional, neoplasia, autoimmune disease, immunosuppression therapy, although the most frequent is the moderate to severe, nutritional failure, differing with the foreign literature. All of them had a good clinical evolution using Albendazole in high doses or Ivermectin. It is concluded that systemic strongyloidiasis has a clear physiopathological base in relation to cellular immunodeficiency and this must be carefully search in our patients, where the chronic autoinfection is a frequent clinical status, and there are immersed in some type of immunodeficiency, in our environment this is usually nutritional.
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Affiliation(s)
- J Zavala
- Departamento de Medicina, Hospital de Loayza
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Zavala J, Rosado R. [Pneumocystis carinii in domestic animals of the city of Mexico, Yucatan]. Salud Publica Mex 1972; 14:103-6. [PMID: 4546643] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
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Biagi F, Zavala J, Malagon F. [Antiparasitic activity of compound 16,842 in uncinariasis and trichocephaliasis]. Rev Inst Med Trop Sao Paulo 1969; 11:444-8. [PMID: 5372719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
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Biagi F, Zavala J, Malagón F. [Comparison of two methods of egg counting in fecal material, in relation to its efficiency in evaluating antiparasitic drugs]. Bol Chil Parasitol 1967; 22:99-104. [PMID: 5628472] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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