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Elshanbary AA, Awad AA, Abdelsalam A, Ibrahim IH, Abdel-Aziz W, Darwish YB, Isa AS, Drid B, Mustafa MG, Allam RH, Abo Ali AA, Nourelden AZ, Ragab KM, AlGwaiz HIM, Awaji AA, Germoush MO, Albrakati A, Piscopo M, Ghaboura N, Zaazouee MS. The diagnostic accuracy of intraoperative frozen section biopsy for diagnosis of sentinel lymph node metastasis in breast cancer patients: a meta-analysis. Environ Sci Pollut Res Int 2022; 29:47931-47941. [PMID: 35543788 PMCID: PMC9252966 DOI: 10.1007/s11356-022-20569-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Accepted: 04/28/2022] [Indexed: 06/15/2023]
Abstract
Sentinel lymph node (SLN) sampling is important for evaluating the nodal stage of breast cancer when the axillary nodes are clinically free of metastasis. The intraoperative frozen section (IFS) of SLN is used for lymph node assessment. This meta-analysis aims to provide evidence about the diagnostic accuracy and the applicability of IFS of SLN in breast cancer patients. Data were collected by searching PubMed, Cochrane, Scopus, and Web of Science electronic databases for trials matching our eligibility criteria. The statistical analysis included the sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and pooled studies' diagnostic odds ratio outcomes. The analyses were conducted using the Open Meta-analyst software. This meta-analysis pooled the results of 110 studies. The overall sensitivity of IFS for SLN metastasis was 74.7%; 95% CI [72.0, 77.2], P < 0.001. It was 31.4% 95% CI [25.2, 38.3], P < 0.001 for the micro-metastasis, and 90.2%; 95% CI [86.5, 93.0], P < 0.001 for the macro-metastasis. The overall specificity was 99.4%; 95% CI [99.2, 99.6], P < 0.001. The overall positive likelihood ratio was 121.4; 95% CI [87.9, 167.6], P < 0.001, and the overall negative likelihood ratio was 0.226; 95% CI [0.186, 0.274], P < 0.001. The overall diagnostic odds ratio of IFS for diagnosing SLN metastasis was 569.5; 95% CI [404.2, 802.4], P < 0.001. The intraoperative frozen section of SLN has good sensitivity for diagnosing breast cancer macro-metastasis. However, the sensitivity is low for micro-metastasis. The specificity is very satisfactory.
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Affiliation(s)
- Alaa Ahmed Elshanbary
- Faculty of Medicine, Alexandria University, Alexandria, Egypt
- International Medical Research Association (IMedRA), Cairo, Egypt
| | - Alaa Abdelsameia Awad
- International Medical Research Association (IMedRA), Cairo, Egypt
- Faculty of Medicine, Zagazig University, Zagazig, Egypt
| | - Alaa Abdelsalam
- International Medical Research Association (IMedRA), Cairo, Egypt
- Faculty of Medicine, Zagazig University, Zagazig, Egypt
| | - Islam H Ibrahim
- International Medical Research Association (IMedRA), Cairo, Egypt
- Faculty of Medicine, Assiut University, Assiut, Egypt
| | - Walid Abdel-Aziz
- International Medical Research Association (IMedRA), Cairo, Egypt
- Faculty of Medicine, Al-Azhar University, Assiut, Egypt
| | - Youssef Bahaaeldin Darwish
- International Medical Research Association (IMedRA), Cairo, Egypt
- Faculty of Pharmacy, Mansoura University, Mansoura, Egypt
| | - Alaa Saad Isa
- International Medical Research Association (IMedRA), Cairo, Egypt
- Faculty of Medicine, Al-Azhar University, Damietta, Egypt
| | - Boutheyna Drid
- International Medical Research Association (IMedRA), Cairo, Egypt
- Faculty of Medicine, Batna 2 University, Batna, Algeria
| | - Marwa Gamal Mustafa
- International Medical Research Association (IMedRA), Cairo, Egypt
- Faculty of Pharmacy, Fayoum University, Fayoum, Egypt
| | - Radwa Hamdy Allam
- International Medical Research Association (IMedRA), Cairo, Egypt
- Faculty of Medicine, Fayoum University, Fayoum, Egypt
| | - Amira A Abo Ali
- Faculty of Medicine, Alexandria University, Alexandria, Egypt
- International Medical Research Association (IMedRA), Cairo, Egypt
| | - Anas Zakarya Nourelden
- International Medical Research Association (IMedRA), Cairo, Egypt
- Faculty of Medicine, Al-Azhar University, Cairo, Egypt
| | - Khaled Mohamed Ragab
- International Medical Research Association (IMedRA), Cairo, Egypt
- Faculty of Medicine, Minia University, Minia, Egypt
| | - Hussah I M AlGwaiz
- Department of Biology, College of Science, Princess Nourah Bint Abdulrahman University, Riyadh, 11474, Saudi Arabia
| | - Aeshah A Awaji
- Department of Biology, Faculty of Science, University College of Taymaa, University of Tabuk, Tabuk, 71491, Saudi Arabia
| | - Mousa O Germoush
- Biology Department, College of Science, Jouf University, P.O. Box: 2014, Sakaka, Saudi Arabia
| | - Ashraf Albrakati
- Department of Human Anatomy, College of Medicine, Taif University, P.O. Box 11099, Taif, 21944, Saudi Arabia
| | - Marina Piscopo
- Department of Biology, University of Naples Federico II, Via Cinthia, 80126, Naples, Italy
| | - Nehmat Ghaboura
- Department of Pharmacy Practice, Batterjee Medical College, Pharmacy Program, P.O. Box 6231, Jeddah, 21442, Saudi Arabia
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Abstract
Penetrating injury in the neck is not an uncommon condition, but a perforating foreign body like bamboo in the neck is uncommon. A 36 years old young man was admitted in Otolaryngology and Head Neck surgery department, Mymensingh Medical College hospital, with a history of accidental perforating injury in the neck with a bamboo, while driving a vehicle (tempo). Clinical examination revealed a bamboo measuring 4.6 X 0.09 ft. perforated in his neck from left to right. Surprisingly great vessels and air way spared. Due to difficult intubation, elective tracheostomy was done. Neck was explored and foreign body removed under general anesthesia. Haemostasis ensured and wound closed in layers after putting drain tubes. Recovery was uneventful and was discharged after three weeks.
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Affiliation(s)
- M K Khan
- Mymensingh Medical College and Hospital, Mymensingh
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Abstract
The present study demonstrates that exposure to ozone (O3) and nitrogen dioxide (NO2) can cause DNA single-strand breaks in alveolar macrophages. Three-month-old male Sprague-Dawley rats, specific pathogen free, were exposed to either 1.2 ppm NO2 or 0.3 ppm O3 alone or a combination of these two oxidants continuously for 3 days. The control group was exposed to filtered room air. The oxidant effects were substantiated by determining total and differential cell counts, lactate dehydrogenase activity, and total soluble protein in bronchoalveolar lavage. DNA damage was measured as single-strand breaks by alkaline elution assay. The results showed that, relative to control, NO2 exposure did not cause any significant change in the parameters studied. Exposure to O3 and combined exposure to NO2 and O3 caused significant changes in all parameters studied except cell viability. The rates of elution (Kc) of single-strand DNA from polycarbonate filter for O3 exposure and combined exposure were 73 and 79% faster than that of the control, respectively. The amounts of DNA single-strand breaks caused by O3 and combined exposure were significantly greater than the amounts detected for the NO2-exposed and control groups.
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Affiliation(s)
- E Bermúdez
- School of Health and Human Performance, Indiana State University, Terre Haute, Indiana 47809, USA.
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Ferng SF, Castro CE, Afifi AA, Bermúdez E, Mustafa MG. Ozone-induced DNA strand breaks In guinea pig tracheobronchial epithelial cells. J Toxicol Environ Health 1997; 51:353-67. [PMID: 9202716 DOI: 10.1080/00984109708984030] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Ozone (O3), the major oxidant of photochemical smog, is thought to be genotoxic and a potential respiratory carcinogen or promoter of carcinogenic processes. Because of oxidative reactions with the mucus in the upper airway, O3 reaction products are able to penetrate into the tracheobronchial epithelial (TE) cells. The carcinogenic effects of O3 on the TE cells are especially of interest since most previous studies have focused on the morphology or permeability changes of tracheas only. Therefore, the objective of this study was to examine the potential O3 genotoxicity in TE cells after an in vivo exposure, using DNA strand breaks as an index. Two-month-old male Dunkin-Hartley guinea pigs, specific pathogen free, 4 in each group, were exposed to 1.0 ppm O3 for 0, 12, 24, 48, 72, or 96 h. Animals exposed to filtered air without O3 exposure were used as controls. After O3 exposure, the trachea with two main bronchi was removed from each animal, and TE cells were isolated and employed for determination of DNA strand breaks by fluorometric analysis of DNA unwinding (FADU). The statistical significance level was set at alpha = .05. Compared with controls, ozone exposure did not alter the TE cell yield or viability, but caused an increase in protein content in tracheal lavage and an increase in DNA strand breaks. The amount of DNA left in the alkali lysate of TE cells found at 72 h exposure was significantly decreased from controls for 3 different alkali incubation times. An increase of the double-stranded DNA left in the alkali lysate of TE cells was observed at 96 h of exposure and approached the value of 24 h of exposure. The same pattern was seen with all 3 different alkali incubation times at 15 degrees C. One Qd unit was estimated to correspond to 100 strand breaks per cell. The Qd was also used as an indicator for O3 damage. Compared to controls, the Qd increases significantly after 1 ppm O3 exposure for 72 h, regardless of the alkali incubation time at 15 degrees C.
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Affiliation(s)
- S F Ferng
- Department of Health and Safety, School of Health and Human Performance, Indiana State University, Terre Haute 47809, USA.
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Mustafa MG, Ansari A. Erratum: Strangelets at finite temperature. Phys Rev D Part Fields 1996; 54:4694. [PMID: 10021154 DOI: 10.1103/physrevd.54.4694] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Mustafa MG, Ansari A. Strangelets at finite temperature. Phys Rev D Part Fields 1996; 53:5136-5141. [PMID: 10020513 DOI: 10.1103/physrevd.53.5136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Mustafa MG, Blann M, Peilert G, Botvina A. Comparison of fast cascade plus statistical models for heavy ion induced multifragmentation reactions. Phys Rev C Nucl Phys 1994; 49:2602-2607. [PMID: 9969509 DOI: 10.1103/physrevc.49.2602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Mustafa MG. Finite-size effects on asymptotic mass spectrum in the MIT bag. Phys Rev D Part Fields 1994; 49:4634-4641. [PMID: 10017467 DOI: 10.1103/physrevd.49.4634] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Mustafa MG, Blann M, Ignatyuk AV. Realistic level densities in fragment emission at high excitation energies. Phys Rev C Nucl Phys 1993; 48:588-592. [PMID: 9968867 DOI: 10.1103/physrevc.48.588] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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West HI, Nuckolls RM, Hudson B, Ruiz B, Lanier RG, Mustafa MG. Bromine and iodine excitation-function measurements with protons and deuterons at 3-17 MeV. Phys Rev C Nucl Phys 1993; 47:248-259. [PMID: 9968432 DOI: 10.1103/physrevc.47.248] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Peilert G, Konopka J, Stöcker H, Greiner W, Blann M, Mustafa MG. Dynamical treatment of Fermi motion in a microscopic description of heavy ion collisions. Phys Rev C Nucl Phys 1992; 46:1457-1473. [PMID: 9968255 DOI: 10.1103/physrevc.46.1457] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Blann M, Mustafa MG. Multifragmentation for 36Ar+238U treated as statistical dynamic interaction processes. Phys Rev C Nucl Phys 1991; 44:R590-R593. [PMID: 9967491 DOI: 10.1103/physrevc.44.r590] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Blann M, Mustafa MG, Peilert G, Stöcker H, Greiner W. Expectations of fragment decay from highly excited nuclei. Phys Rev C Nucl Phys 1991; 44:431-439. [PMID: 9967413 DOI: 10.1103/physrevc.44.431] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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15
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West HI, Mustafa MG, Lanier RG, O'Brien H. Interpretation of ion-range recoil data obtained from activated-foil measurements of nuclear excitation functions. Phys Rev C Nucl Phys 1991; 43:1352-1362. [PMID: 9967174 DOI: 10.1103/physrevc.43.1352] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Elsayed NM, Mustafa MG, Mead JF. Increased vitamin E content in the lung after ozone exposure: a possible mobilization in response to oxidative stress. Arch Biochem Biophys 1990; 282:263-9. [PMID: 2241150 DOI: 10.1016/0003-9861(90)90115-f] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Vitamin E (vE) is a biological free radical scavenger capable of providing antioxidant protection depending upon its tissue content. In previous studies, we observed that vE increased significantly in rat lungs after oxidant exposure, and we postulated that vE may be mobilized to the lung from other body sites under oxidative stress. To test this hypothesis, we fed Long-Evans rats either a vE-supplemented or a vE-deficient diet, injected them intraperitoneally with 14C-labeled vE, and then exposed half of each group to 0.5 ppm ozone (O3) for 5 days. After exposure, we determined vE content and label retention in lungs, liver, kidney, heart, brain, plasma, and white adipose tissue. Tissue vE content of all tissues generally reflected the dietary level, but labeled vE retention in all tissues was inversely related to tissue content, possibly reflecting a saturation of existing vE receptor sites in supplemented rats. Following O3 exposure, lung vE content increased significantly in supplemented rats and decreased in deficient rats, but the decrease was not statistically significant, and vE content remained unchanged in all other tissues of both dietary groups. Retention of 14C-labeled vE increased in all tissues of O3-exposed rats of both dietary groups, except in vE-deficient adipose tissue and vE-supplemented brain, where it decreased, and plasma, where it did not change. The marked increases in lung vE content and labeled vE retention of O3-exposed vE-supplemented rats support our hypothesis that vE may be mobilized to the lung in response to oxidative stress, providing that the vitamin is sufficiently available in other body sites.
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Affiliation(s)
- N M Elsayed
- Letterman Army Institute of Research, Presidio of San Francisco, California 94129
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Lanier RG, West HI, Mustafa MG, Frehaut J, Adam A, Philis CA. Effects of nuclear deformation on 151,153Eu(p,n)151,153Gd reactions. Phys Rev C Nucl Phys 1990; 42:R479-R482. [PMID: 9966780 DOI: 10.1103/physrevc.42.r479] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Mastroleo RC, Udagawa T, Mustafa MG. Calculations of complete fusion, incomplete fusion, and direct reaction cross sections for deuteron-induced reactions. Phys Rev C Nucl Phys 1990; 42:683-689. [PMID: 9966756 DOI: 10.1103/physrevc.42.683] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Lee JS, Mustafa MG, Afifi AA. Effects of short-term, single and combined exposure to low-level NO2 and O3 on lung tissue enzyme activities in rats. J Toxicol Environ Health 1990; 29:293-305. [PMID: 2313741 DOI: 10.1080/15287399009531392] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
To examine the pulmonary effects of relatively low levels of NO2 and O3, and test for any possible interaction in their effects, we exposed 3-mo-old male Sprague-Dawley rats, free of specific pathogens, to either filtered room air (control) or 1.20 ppm (2256 micrograms/m3) NO2, 0.30 ppm (588 micrograms/m3) O3, or a combination of the two oxidants continuously for 3 d. We studied a series of parameters in the lung, including lung weight, and enzyme activities related to NADPH generation, sulfhydryl metabolism, and cellular detoxification. The results showed that relative to control, exposure to NO2 caused small but nonsignificant changes in all the parameters; O3 caused significant increases in all the parameters except for superoxide dismutase; and a combination of NO2 and O3 caused increases in all the parameters, and the increases were greater than those caused by NO2 or O3 alone. Statistical analysis of the data showed that the effects of combined exposure were synergistic for 6-phosphogluconate dehydrogenase, isocitrate dehydrogenase, glutathione reductase, and superoxide dismutase activities, and additive for glutathione peroxidase and disulfide reductase activities, but indifferent from those of O3 exposure for other enzyme activities.
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Affiliation(s)
- J S Lee
- Department of Environmental Health Sciences, School of Public Health, University of California, Los Angeles 90024
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Elsayed NM, Ellingson AS, Tierney DF, Mustafa MG. Effects of ozone inhalation on polyamine metabolism and tritiated thymidine incorporation into DNA of rat lungs. Toxicol Appl Pharmacol 1990; 102:1-8. [PMID: 2296762 DOI: 10.1016/0041-008x(90)90078-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
We examined the effects of low-level ozone (O3) inhalation on polyamine metabolism and tritiated thymidine (3H-TdR) incorporation into DNA in rat lungs. We have also compared the activities of ornithine decarboxylase (ODC), the rate-limiting enzyme of polyamine biosynthesis, and glucose-6-phosphate dehydrogenase (G6PD), the key enzyme of the pentose phosphate cycle and a typical marker of oxidant injury, to assess whether ODC can serve as a sensitive marker of O3 effects on the lung. We exposed 90-day-old male specific-pathogen-free Sprague-Dawley rats to either 0.45 +/- 0.05 ppm (882 +/- 98 micrograms/m3) O3 or filtered room air continuously for 3 days. After exposure, the rats were terminated and the lungs examined for enzyme activities, polyamine contents, DNA content, and 3H-TdR incorporation. We found that in exposed rats, the enzyme activities were significantly increased (p less than 0.05) relative to air controls. G6PD, 25%, ODC, 147%, and S-adenosylmethionine decarboxylase (AdoMet DC), 86%. Polyamine contents were also affected by O3; putrescine increased 80%, p less than 0.05, spermidine did not change, and spermine decreased 23%, p less than 0.05. 3H-TdR incorporation into DNA was significantly elevated, 155%, p less than 0.001, after O3 exposure while total lung DNA content remained unchanged. The concomitant and large increase in ODC activity (reflecting polyamine metabolism) and DNA labeling (reflecting DNA synthesis and/or repair), indicates a strong correlation between the two and suggests that polyamine metabolism may play an important role in the accelerated cell proliferation associated with O3 injury. Moreover, the greater increase in lung ODC activity compared to other enzymes offers a sensitive marker of the lung response to inhaled O3. We conclude that inhalation of O3 at levels similar to what may be encountered during some smog episodes can result in significant pulmonary biochemical alterations with a potential for long-term consequences. The possible association between ODC activity and DNA labeling may offer a new insight into the mechanism of tissue injury and repair. We also speculate that the changes in lung polyamines may reflect antioxidant and anti-inflammatory functions associated with the cellular defense against oxidant injury.
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Affiliation(s)
- N M Elsayed
- Department of Medicine, School of Public Health, University of California, Los Angeles 90024
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Abstract
Ozone (O3) is the major oxidant of photochemical smog. Its biological effect is attributed to its ability to cause oxidation or peroxidation of biomolecules directly and/or via free radical reactions. A sequence of events may include lipid peroxidation and loss of functional groups of enzymes, alteration of membrane permeability, and cell injury or death. An acute exposure to O3 causes lung injury involving the ciliated cell in the airways and the type 1 epithelial cell in the alveolar region. The effects are particularly localized at the junction of terminal bronchioles and alveolar ducts, as evident from a loss of cells and accumulation of inflammatory cells. In a typical short-term exposure the lung tissue response is biphasic: an initial injury-phase characterized by cell damage and loss of enzyme activities, followed by a repair-phase associated with increased metabolic activities, which coincide with a proliferation of metabolically active cells, for example, the alveolar type 2 cells and the bronchiolar Clara cells. A chronic exposure to O3 can cause or exacerbate lung diseases, including perhaps an increased lung tumor incidence in susceptible animal models. Ozone exposure also causes extrapulmonary effects involving the blood, spleen, central nervous system, and other organs. A combination of O3 and NO2, both of which occur in photochemical smog, can produce effects which may be additive or synergistic. A synergistic lung injury occurs possibly due to a formation of more powerful radicals and chemical intermediates. Dietary antioxidants, for example, vitamin E, vitamin C, and selenium, can offer a protection against O3 effects.
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Affiliation(s)
- M G Mustafa
- Department of Environmental Health Sciences, School of Public Health, University of California, Los Angeles 90024
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Abstract
While the pulmonary toxicity of NO2 is clearly established, the mechanism by which it is removed from inspired air is poorly understood. Uptake is most likely dependent on chemical reaction since, despite limited per se gaseous NO2 aqueous solubility, uptake proceeds rapidly without ready saturation. We utilized an isolated perfused rat lung model to characterize the effect of dose rate on uptake and transformation. Dose rate was varied via alterations in inspired concentration, tidal volume, and ventilation frequency. Dose equaled the total amount inhaled, uptake the amount removed from inspired air, and transformation the amount of NO2- that accumulated in the perfusate. We found a linear proportionality between both inspired concentration (4-20 ppm) and minute ventilation (45-130 ml/min) and uptake. Fractional uptakes (65%) were similar for all groups. Regression of combined concentration and minute ventilation data yielded a linear relationship between total inspired dose (25-330 micrograms NO2) and both uptake (r2 = 0.99) and transformation (r2 = 0.98). Testing of the functional descriptions resulted in measured uptakes and transformation that fell within a few percentage points of those predicted. We conclude that in acutely exposed isolated lungs (1) NO2 uptake is dependent on total inhaled dose rather than on the variables which serve to affect dose rate, (2) transformation is related to both total inspired dose and uptake, and (3) uptake is more accurately described using a regression equation rather than by use of fractional uptakes.
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Affiliation(s)
- E M Postlethwait
- Department of Internal Medicine, University of Texas Medical Branch, Galveston 77550
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Mustafa MG, West HI, O'Brien H, Lanier RG, Benhamou M, Tamura T. Measurements and a direct-reaction-plus-Hauser-Feshbach analysis of 89Y(p,n)89Zr, 89Y(p,2n)88, and 89Y(p,pn)88Y reactions up to 40 MeV. Phys Rev C Nucl Phys 1988; 38:1624-1637. [PMID: 9954974 DOI: 10.1103/physrevc.38.1624] [Citation(s) in RCA: 34] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Affiliation(s)
- M G Mustafa
- Division of Environmental and Occupational Health Sciences, School of Public Health, University of California, Los Angeles 90024
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Mustafa MG, Tamura T, Udagawa T. Direct-reaction plus statistical-model analysis of the 52Cr(d,2n)52Mng,m reaction. Phys Rev C Nucl Phys 1987; 35:2077-2085. [PMID: 9954003 DOI: 10.1103/physrevc.35.2077] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Abstract
We have previously examined the influence of animal age on the pulmonary response to ozone (O3) in rats between 7 and 90 days of age (Elsayed et al., 1982a). In the present study, we expanded the age groups of rats, and examined in greater detail the relationship between animal age and pulmonary response to inhaled O3. We exposed 7 groups of specific pathogen free, male Sprague-Dawley rats, aged 24, 30, 45, 60, 90, 180, and 365 days, to 0.8 ppm (1568 micrograms/m3) O3 continuously for 3 days. After O3 exposure, we sacrificed the exposed rats and a matched number of controls from each age group, and analyzed their lungs for a series of physical and biochemical parameters, including glutathione metabolizing and NADPH producing enzyme activities. We observed that in control rats all the parameters increased as a function of age. However, the rate of increase was generally slower after age 60 days. After O3 exposure there was an increase in all the parameters for all age groups relative to their corresponding controls, but the extent of increase was significantly larger in rats 60 days and older than in younger rats. A regression of the difference in mean values between control and exposed animals for each parameter against age showed a linear correlation, indicating that the response was age-dependent. Since the magnitude of such increases is thought to reflect the degree of lung injury, the results suggest that O3 exposure causes greater lung injury in older rats than in younger rats. We tested this assumption by exposing rats from four different age groups (24, 45, 60 and 90 days) to a lethal dose of O3 (4 ppm or 7840 micrograms/m3 for 8 hours). The mortality rates were 50% and 83% for 24 and 45 day old rats, respectively, and 100% for 60 and 90 day old rats. The results of these studies further demonstrate that older rats are more susceptible to lung injury from O3 than younger rats.
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Hassett C, Mustafa MG, Coulson WF, Elashoff RM. Murine lung carcinogenesis following exposure to ambient ozone concentrations. J Natl Cancer Inst 1985; 75:771-7. [PMID: 3862908] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Inbred strain A/J mice, responsive to the chemical induction of pulmonary adenomas, were used to assess any of several roles that the photochemical air pollutant ozone might play in lung carcinogenesis. In separate experiments, animals were exposed to two concentrations of ozone (0.31 +/- 0.01 and 0.50 +/- 0.02 ppm) intermittently for a 6-month period, to evaluate the potential of ozone to act as either a pulmonary carcinogen, a tumor promoter, or an inhalant capable of increasing lung tumor yield when exposure was in conjunction with a pulmonary carcinogen, urethane. Statistical analyses of results indicated that ozone exposure at both concentrations caused an increase in lung tumor number relative to clean air controls, but that ozone was not an effective tumor promoter under the conditions of our protocol. When ozone exposure immediately preceded treatment with urethane (CAS: 51-79-6), animals were at increased risk for the development of lung adenomas.
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Hussain MZ, Mustafa MG, Ghani QP, Bhatnagar RS. Stimulation of poly(ADP-ribose) synthetase activity in the lungs of mice exposed to a low level of ozone. Arch Biochem Biophys 1985; 241:477-85. [PMID: 2994569 DOI: 10.1016/0003-9861(85)90573-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Toxic effects of O3 are mediated through the formation of free radicals, which can cause DNA strand breaks. Cellular DNA repair is dependent upon the formation of poly(ADP-ribose) (polyADPR) catalyzed by polyADPR synthetase. In order to evaluate whether O3 exposure inflicted DNA damage in lung tissue, we measured the activity of polyADPR synthetase (known to be activated in response to DNA damage) in mouse lungs after exposure to 0.45 ppm (882 micrograms/m3) O3 for up to 7 days. The enzyme activity was stimulated with O3 exposure relative to unexposed controls, showing a 20% (P less than 0.05) increase at Day 5 and 42% (P less than 0.001) at Day 7 of O3 exposure. In addition, the activity of superoxide dismutase (SOD), known to be stimulated in response to production of superoxide anion (.O2-), was measured as an indicator of free radical involvement. Relative to unexposed controls, the SOD activity in exposed animal lungs increased to the peak level at Day 5 (48%, P less than 0.001) and then declined at Day 7 of O3 exposure but was still higher than controls (17%, P less than 0.05). When animals, after 5 days of O3 exposure, were allowed to recover in filtered room air, the activities of both enzymes declined to their respective control values in 6 days. These results suggest a possible temporal relationship between O3 injury and the activities of polyADPR synthetase and a free radical scavenging enzyme, SOD. The stimulation of polyADPR synthetase activity with O3 exposure, reflecting a response to lung cellular DNA repair, may be a sensitive indicator for assessing DNA damage in oxidant injury.
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Abstract
Female strain A/J mice were exposed to 0.31 ppm (608 micrograms/m3) ozone continuously for 103 h every other week for 6 mth. Following an additional period of 5 mth in a filtered air environment, animals were killed and examined for evidence of altered spleen weight. It was observed that animals exposed to ozone had a greater spleen weight, and spleen to body weight ratio than air-breathing controls. In some of the ozone-exposed mice, pronounced splenomegaly was noted. Increased spleen weight appears to be another example of an extrapulmonary effect of ozone inhalation.
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McMahan MA, Moretto LG, Padgett ML, Wozniak GJ, Sobotka LG, Mustafa MG. Mass-asymmetric barriers from excitation functions for complex-fragment emission. Phys Rev Lett 1985; 54:1995-1998. [PMID: 10031196 DOI: 10.1103/physrevlett.54.1995] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Elsayed NM, Mustafa MG, Hacker AD, Kuehn K, Schrauzer GN. Dietary antioxidants and the biochemical response to oxidant inhalation : III. Selenium influence on mouse lung response and tolerance to ozone. Biol Trace Elem Res 1984; 6:249-61. [PMID: 24264024 DOI: 10.1007/bf02917510] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/15/1983] [Accepted: 01/10/1984] [Indexed: 10/21/2022]
Abstract
We fed female strain A/St mice selenium (Se) test diets containing either no Se (-Se) or 1 ppm Se (+Se) for 11 wk. Both diets contained 55 ppm vitamin E. We then exposed three groups of mice from each dietary regimen to either 0.8 ppm (1568 μg/m(3)) O3 (low-level) continuously for 5 d, 10.0 ppm (19,600 μg/m(3)) O3 (high-level) for 12 h, or filtered room air, where the latter served as a control for both O3 exposures. After O3 exposures we analyzed the lungs for various physical and biochemical parameters, and compared the results to those obtained from the air controls. The results showed that the difference in dietary Se intake produced an eightfold difference in Se content and a three-fold difference in glutathione peroxidase (GP) activity in the lung, but few changes in other lung parameters. With low-level O3 exposure, NADPH production increased significantly in +Se mice, but did not change in -Se mice. With high-level O3 exposure we observed comparable effects for both dietary regimens, including animal mortality, which was 24% for -Se and 14% for +Se mice. Thus, it seems that diminished GP activity resulting from Se deficiency and the ensuing lack of increase in NADPH production were poorly correlated with mouse tolerance to O3. The lung Se content increased in both dietary regimens after O3 exposure, but the increase was greater after high-level O3 exposure. This suggests a "mobilization" of Se to the lung under O3 stress. It is possible that such a mobilization contributes to the lung reserve of antioxidants, and hence the comparable mortality in both dietary Se regimens.
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Affiliation(s)
- N M Elsayed
- Division of Environmental and Occupational Health Sciences, School of Public Health, University of California, 90024, Los Angeles, California
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Mustafa MG, Elsayed NM, von Dohlen FM, Hassett CM, Postlethwait EM, Quinn CL, Graham JA, Gardner DE. A comparison of biochemical effects of nitrogen dioxide, ozone, and their combination in mouse lung. Toxicol Appl Pharmacol 1984; 72:82-90. [PMID: 6710487 DOI: 10.1016/0041-008x(84)90251-5] [Citation(s) in RCA: 34] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Swiss Webster mice were exposed to either 4.8 ppm (9024 microgram/m3) nitrogen dioxide (NO2), 0.45 ppm (882 microgram/m3) ozone (O3), or their combination intermittently (8 hr daily) for 7 days, and the effects were studied in the lung by a series of physical and biochemical parameters, including lung weight, DNA and protein contents, oxygen consumption, sulfhydryl metabolism, and activities of NADPH generating enzymes. The results show that exposure to NO2 caused relatively smaller changes than O3, and that the effect of each gas alone under the conditions of exposure was not significant for most of the parameters tested. However, when the two gases were combined, the exposure caused changes that were greater and significant. Statistical analysis of the data shows that the effects of combined exposure were more than additive, i.e., they might be synergistic. The observations suggest that intermittent exposure to NO2 or O3 alone at the concentration used may not cause significant alterations in lung metabolism, but when the two gases are combined the alterations may become significant.
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Elsayed NM, Hacker AD, Kuehn K, Mustafa MG, Schrauzer GN. Dietary antioxidants and the biochemical response to oxidant inhalation. II. Influence of dietary selenium on the biochemical effects of ozone exposure in mouse lung. Toxicol Appl Pharmacol 1983; 71:398-406. [PMID: 6658789 DOI: 10.1016/0041-008x(83)90027-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
We examined the influence of dietary selenium (Se) on the pulmonary biochemical response to ozone (O3) exposure. For 11 weeks, weanling female strain A/St mice were fed a test diet containing Se either at 0 ppm (-Se) or 1 ppm (+Se). Each diet contained 55 ppm vitamin E (vit E). Mice from each dietary group were exposed to 0.8 +/- 0.05 ppm (1568 +/- 98 micrograms/m3) O3 continuously for 5 days. After O3 exposure, they were killed along with a matched number of unexposed controls, and their lungs were analyzed for various biochemical parameters. The Se contents of lung tissue and whole blood were determined, and the levels were seven- to eightfold higher in +Se mice than in -Se mice, reflecting the Se intake of the animals. In unexposed control mice, Se deficiency caused a decline in glutathione peroxidase (GP) activity relative to +Se group. After O3 exposure, the GP activity in the -Se group was associated with a lack of stimulation of glutathione reductase (GR) activity and the pentose phosphate cycle (PPC) as assessed by measuring glucose-6-phosphate dehydrogenase (G6PD) and 6-phosphogluconate dehydrogenase (6PGD) activities. In contrast, the +Se group after O3 exposure exhibited increases in all four enzyme activities. Other parameters, e.g., lung weight, total lung protein, DNA and nonprotein sulfhydryl contents, and O2 consumption, were not affected by dietary Se in the presence or absence of O3 exposure. The data indicate that dietary Se alters the GP activity, which in turn influences the GR and PPC activities in the lung evidently through a reduced demand for NADPH. The level of vit E in the lung was found to be twofold higher in the -Se group than in the +Se group, suggesting a compensatory relationship between Se and vit E in the lung. With O3 exposure, both Se and vit E contents further increased in the lungs of each dietary group. It is plausible that Se and vit E under oxidant stress are "mobilized" to the lung from other body sites.
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Abstract
An isolated rat lung preparation was ventilated with NO2 while being perfused with a medium containing morpholine. After 60 min of ventilation-perfusion, N-nitrosomorpholine was detected in both lung tissue and perfusate.
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Elsayed NM, Mustafa MG. Dietary antioxidants and the biochemical response to oxidant inhalation. I. Influence of dietary vitamin E on the biochemical effects of nitrogen dioxide exposure in rat lung. Toxicol Appl Pharmacol 1982; 66:319-28. [PMID: 7167960 DOI: 10.1016/0041-008x(82)90298-8] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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Abstract
The influence of age on O3 effects in the lung was studied in 8 groups of Sprague-Dawley rats: 7, 12, and 18 d of age (neonatal); 24, 30, and 45 d of age (infant); and 60 and 90 d of age (adult). Lung weight, total lung protein and DNA contents, and a series of marker enzyme activities in lung tissue were determined. After exposure of rats from each group to 0.8 ppm (1568 microgram/m3) O3 continuously for 3 d, a biphasic effect was noted. The biochemical parameters, expressed per lung, in O3-exposed rats relative to their corresponding controls decreased in the 7- and 12-d-old groups, increased or remained unchanged in the 18-d-old group, and increased in the 24- to 90-d-old groups. However, the increases were much greater for 60- to 90-d-old rats than for 24- to 30-d-old rats. The increase in lung biochemical parameters is thought to occur in response to lung injury and subsequent repair processes, and greater increases in the lungs of older rats suggest that they are more responsive to O3 exposure than younger rats. The decrease in lung biochemical parameters and increased mortality in 7- and 24-d-old neonatal rats suggest that they are more susceptible to O3 stress than infant and adult rats.
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Mustafa MG, Elsayed NM, Quinn CL, Postlethwait EM, Gardner DE, Graham JA. Comparison of pulmonary biochemical effects of low-level ozone exposure on mice and rats. J Toxicol Environ Health 1982; 9:857-65. [PMID: 7120513 DOI: 10.1080/15287398209530208] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The biochemical effects of a 5-d continuous exposure to 0.45 ppm (882 microgram/m3) O3, were studied in the lungs of 2-mo-old male, specific-pathogen-free mice (Swiss Webster) and three strains of rats (Long-Evans, Wistar, and Sprague-Dawley). The results, expressed per lung, indicated a general increase in lung weight, DNA and protein contents, oxygen consumption, sulfhydryl metabolism, and the activities of several NADP+-reducing enzymes for all exposed animals relative to their controls. When the increases in the two species (mice versus three strains of rats) were compared, the mice showed significantly higher increases than the rats in several parameters. The responses among the three strains of rats were variable, but the differences were not significant. These observations suggest that Swiss Webster mice may offer a more sensitive animal model than rats for studying the pulmonary effects of a given low-level O3 exposure.
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Abstract
Sixty-day-old male, specific pathogen-free rats were exposed continuously to 5 or 15 ppm NO2 for 1-7 d. Lung tissue from exposed and control rats was then analyzed for biochemical and enzymatic parameters. The exposure resulted in increased lung enzymatic activities, including elevated protein and DNA contents and nonprotein sulfhydryl levels. Biochemical and enzymatic parameters generally increased maximally after 4 d and remained elevated for up to 7 d of continued exposure. The magnitude of these increases was higher for 15 than for 4 ppm NO2. The increases in biochemical and enzymatic parameters may have occurred in response to NO2-induced lung injury.
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Abstract
The fate of inhaled NO2 was studied with isolated perfused rat lungs. The isolated lungs were exposed to 5 ppm NO2 for 90 min at a ventilation rate of 34 ml/min. The NO2 exposure had no adverse effects on the lungs as judged from their weights, glucose uptake, or lactate production compared to control lungs. Isolated lungs absorbed 36% of ventilated NO2, which was detected in perfusate and lung tissue as NO2- but not NO3-. The NO2- concentration in perfusate increased linearly with time, and after 90 min of ventilation with NO2 and perfusion with erythrocyte-free medium the NO2- accumulation was 6.36 +/- 0.39 micrograms. If perfusate contained 10% erythrocytes, the ventilated NO2 product was mostly NO3- in perfusate but NO2- in lung tissue. Protein solutions absorbed NO2 more effectively than simple salt solutions, but they all yielded mainly NO2- unless erythrocytes were present, when the product was mostly NO3-. The results indicate that absorbed NO2 in the lung is converted predominantly to NO2-, but after its diffusion into the vascular space it is oxidized to NO3- by interactions with erythrocytes.
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Mustafa MG, Tierney DF. Biochemical and metabolic changes in the lung with oxygen, ozone, and nitrogen dioxide toxicity. Am Rev Respir Dis 1978; 118:1061-90. [PMID: 369411 DOI: 10.1164/arrd.1978.118.6.1061] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Chow CK, Hussain MZ, Cross CE, Dungworth DL, Mustafa MG. Effect of low levels of ozone on rat lungs. I. Biochemical responses during recovery and reexposure. Exp Mol Pathol 1976; 25:182-8. [PMID: 992013 DOI: 10.1016/0014-4800(76)90028-9] [Citation(s) in RCA: 37] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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Schwartz LW, Dungworth DL, Mustafa MG, Tarkington BK, Tyler WS. Pulmonary responses of rats to ambient levels of ozone: effects of 7-day intermittent or continuous exposure. J Transl Med 1976; 34:565-78. [PMID: 933466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Groups of Sprague-Dawley rats were exposed to ozone for either 8 or 24 hours a day for 7 consecutive days to evaluate morphologic changes of the respiratory system. Three levels of exposure (0.2, 0.5, and 0.8 p.p.m. of O3) were selected to simulate moderate to severe episodes of oxidant pollution in urban environments. Morphologic evaluation included light, scanning electron, and transmission electron microscopy. Biochemical parameters which were examined included succinate oxidase, glucose-6-phosphate dehydrogenase, and nicotinamide adenine dinucleotide phosphate-cytochrome c reductase activities. The results indicated that (1) exposure to concentrations as low as 0.2 p.p.m. for 7 days induced pulmonary damage; (2) there was a dose-dependent pulmonary response to the three levels of ozone which was quantitated by alterations in biochemical marker enzyme activities and observed morphologically; (3) proportionate differences were not observed in morphologic characteristics of the lesions or detected in biochemical parameters between rats exposed continuously for 7 days and those exposed intermittently for 8 hours a day for 7 consecutive days; (4) alterations in surface height and granularity of the cytoplasmic luminal projection of Clara cells were subtle changes which were dose-dependent, occurring even at the lowest ozone concentration, and best detected by scanning electron microscopy; (5) alveolar macrophage accumulation within proximal alveoli of alveolar ducts was the most readily detectable morphologic indicator of pulmonary damage; and (6) although the brunt of ozone damage was borne by the centriacinar region, there was damage to cilia and increased ciliogenesis occurring in the trachea and larger conducting airways following exposure of 0.5 and 0.8 p.p.m. of ozone.
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Hussain MZ, Cross CE, Mustafa MG, Bhatnagar RS. Hydroxyproline contents and prolyl hydroxylase activities in lungs of rats exposed to low levels of ozone. Life Sci 1976; 18:897-903. [PMID: 178970 DOI: 10.1016/0024-3205(76)90406-9] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Kimball RE, Reddy K, Peirce TH, Schwartz LW, Mustafa MG, Cross CE. Oxygen toxicity: augmentation of antioxidant defense mechanisms in rat lung. Am J Physiol 1976; 230:1425-31. [PMID: 1275087 DOI: 10.1152/ajplegacy.1976.230.5.1425] [Citation(s) in RCA: 156] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
In studies directed at determining the activities of selected enzymes in lung tissue after in vivo exposure to hyperoxia, 70-day-old rats were exposed to 85% or 90% O2 for 1-14 days. After 7 days of exposure to 90% O2 (1atm), superoxide dismutase activities in mitochondrial and cytosolic fractions increased, respectively, to 245 and 145% of control; glutathione peroxidase, glutathione reductase, and glucose-6-phosphate dehydrogenase activities increased, respectively, to 317, 175, and 413% of control. The levels of reduced glutathione and total nonprotein sulfhydryl compounds were elevated to 195% and 365% of control. Similar changes were observed in rats exposed to 85% O2 for up to 14 days, but to a lesser degree. The changes are interpreted as a reflection of the overall magnitude of oxidant-induced lung injury-reparative processes. The results suggest that hyperoxia induces an increase in lung "antioxidant" defense capabilities. This apparent adaptive response may be important in decreasing the susceptibility of lung tissue to continued O2 toxicity.
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Dungworth DL, Castleman WL, Chow CK, Mellick PW, Mustafa MG, Tarkington B, Tyler WS. Effect of ambient levels of ozone on monkeys. Fed Proc 1975; 34:1670-4. [PMID: 1132526] [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: 12/25/2022]
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DeLucia AJ, Mustafa MG, Hussain MZ, Cross CE. Ozone interaction with rodent lung. III. Oxidation of reduced glutathione and formation of mixed disulfides between protein and nonprotein sulfhydryls. J Clin Invest 1975; 55:794-802. [PMID: 1120782 PMCID: PMC301816 DOI: 10.1172/jci107990] [Citation(s) in RCA: 103] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Nonprotein sulfhydryls (NPSH), a major source of cellular reducing substances, were examined in lung tissue after short-term exposure of rats to O3. While the NPSH level was unaffected by low-level exposures (e.g., 0.8 ppm for up to 24 h or 1.5 ppm for up to 8 h), it was significantly lowered by higher exposure regimens (e.g., 25 per cent after 2 ppm for 8 h and 49 per cent after 4 ppm for 6 h). After exposure to 4 ppm O3 for 6 h the level of reduced glutathione (GSH), which accounted for approximately 90 per cent of NPSH in the lung, decreased 40 per cent but without a rise in the level of oxidized gluathione (GSSG). Treatment of lung homogenate with borohydride led to recovery of NPSH in exposed lungs to control values, suggesting that NPSH or GSH oxidation during in vivo O3 exposure resulted in formation of mixed disulfides with other sulfhydryl (SH) groups of lung tissue. Extracts of borohydride-treated particulate and supernatant fractions of lung homogenate were analyzed for NPSH by paper chromatography. From this analysis GSH appeared to be the only NPSH bound to lung tissue proteins via mixed disulfide linkage. The formation of mixed disulfides appeared to be a transient phenomenon. Immediately after a 4-h exposure to 3 ppm O3 the level of mixed disulfides was small (15 per cent of the total NPSH) but attained a peak (equivalent to 0.6 mumol NPSH/lung) after a recovery for 24 h. However, the level diminished considerably within 48 h of recovery.
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Mustafa MG. Augmentation of mitochondrial oxidative metabolism in lung tissue during recovery of animals from acute ozone exposure. Arch Biochem Biophys 1974; 165:531-8. [PMID: 4441092 DOI: 10.1016/0003-9861(74)90279-3] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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