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Saavedra C, Vallejo A, Longo F, Serrano JJ, Fernández M, Gion M, López-Miranda E, Martínez-Jáñez N, Guerra E, Chamorro J, Rosero D, Velasco H, Martín A, Carrato A, Casado JL, Cortés A. Discordant Humoral and T-Cell Response to mRNA SARS-CoV-2 Vaccine and the Risk of Breakthrough Infections in Women with Breast Cancer, Receiving Cyclin-Dependent Kinase 4 and 6 Inhibitors. Cancers (Basel) 2023; 15:cancers15072000. [PMID: 37046661 PMCID: PMC10093435 DOI: 10.3390/cancers15072000] [Citation(s) in RCA: 2] [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: 12/30/2022] [Revised: 03/09/2023] [Accepted: 03/24/2023] [Indexed: 03/30/2023] Open
Abstract
Few data are available about the immune response to mRNA SARS-CoV-2 vaccines in patients with breast cancer receiving cyclin-dependent kinase 4/6 inhibitors (CDK4/6i). We conducted a prospective, single-center study of patients with breast cancer treated with CDK4/6i who received mRNA-1273 vaccination, as well as a comparative group of healthcare workers. The primary endpoint was to compare the rate and magnitude of humoral and T-cell response after full vaccination. A better neutralizing antibody and anti-S IgG level was observed after vaccination in the subgroup of women receiving CDK4/6i, but a trend toward a reduced CD4 and CD8 T-cell response in the CDK4/6i group was not statistically significant. There were no differences in the rate of COVID-19 after vaccination (19% vs. 12%), but breakthrough infections were observed in those with lower levels of anti-S IgG and neutralizing antibodies after the first dose. A lower rate of CD4 T-cell response was also found in those individuals with breakthrough infections, although a non-significant and similar level of CD8 T-cell response was also observed, regardless of breakthrough infections. The rate of adverse events was higher in patients treated with CDK4/6i, without serious adverse events. In conclusion, there was a robust humoral response, but a blunted T-cell response to mRNA vaccine in women receiving CDK4/6i, suggesting a reduced trend of the adaptative immune response.
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Affiliation(s)
- Cristina Saavedra
- Medical Oncology Department, Ramón y Cajal University Hospital, IRYCIS, 28034 Madrid, Spain
| | - Alejandro Vallejo
- Laboratory of Immunovirology, Department of Infectious Diseases, Ramón y Cajal University Hospital, IRYCIS, 28034 Madrid, Spain
| | - Federico Longo
- CIBERONC, Medical Oncology Department, Ramón y Cajal University Hospital, IRYCIS, Alcalá University, 28034 Madrid, Spain
| | - Juan José Serrano
- Medical Oncology Department, Ramón y Cajal University Hospital, IRYCIS, 28034 Madrid, Spain
| | - María Fernández
- Medical Oncology Department, Ramón y Cajal University Hospital, IRYCIS, 28034 Madrid, Spain
| | - María Gion
- Medical Oncology Department, Ramón y Cajal University Hospital, IRYCIS, 28034 Madrid, Spain
| | - Elena López-Miranda
- Medical Oncology Department, Ramón y Cajal University Hospital, IRYCIS, 28034 Madrid, Spain
| | - Noelia Martínez-Jáñez
- Medical Oncology Department, Ramón y Cajal University Hospital, IRYCIS, 28034 Madrid, Spain
| | - Eva Guerra
- Medical Oncology Department, Ramón y Cajal University Hospital, IRYCIS, 28034 Madrid, Spain
| | - Jesús Chamorro
- Medical Oncology Department, Ramón y Cajal University Hospital, IRYCIS, 28034 Madrid, Spain
| | - Diana Rosero
- Medical Oncology Department, Ramón y Cajal University Hospital, IRYCIS, 28034 Madrid, Spain
| | - Héctor Velasco
- CiberInfect, Infectious Disease Department, Ramón y Cajal University Hospital, 28034 Madrid, Spain
| | - Adrián Martín
- CiberInfect, Infectious Disease Department, Ramón y Cajal University Hospital, 28034 Madrid, Spain
| | - Alfredo Carrato
- CIBERONC, Medical Oncology Department, Ramón y Cajal University Hospital, IRYCIS, Alcalá University, 28034 Madrid, Spain
| | - José Luis Casado
- CiberInfect, Infectious Disease Department, Ramón y Cajal University Hospital, 28034 Madrid, Spain
- Correspondence: (J.L.C.); (A.C.)
| | - Alfonso Cortés
- Medical Oncology Department, Ramón y Cajal University Hospital, IRYCIS, 28034 Madrid, Spain
- Correspondence: (J.L.C.); (A.C.)
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Vallejo A, Vizcarra P, Martín-Hondarza A, Gómez-Maldonado S, Haemmerle J, Velasco H, Casado JL. Impact of SARS-CoV-2-specific memory B cells on the immune response after mRNA-based Comirnaty vaccine in seronegative health care workers. Front Microbiol 2022; 13:1002748. [PMID: 36212856 PMCID: PMC9535088 DOI: 10.3389/fmicb.2022.1002748] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Accepted: 09/08/2022] [Indexed: 12/04/2022] Open
Abstract
Purpose To analyze the impact of SARS-COV-2-specific memory B cells (MBC) on the immune response after two doses of mRNA-based Comirnaty COVID-19 vaccine in seronegative health care workers. This study is seeking a rationale for boosting vaccines. Methods Longitudinal study including 31 seronegative health care workers with undetectable specific MBCs (IgG−MBC− group), 24 seronegative with detectable specific MBCs (IgG−MBC+ group), and 24 seropositive with detectable specific MBCs (IgG+MBC+ group). The level of antibodies that inhibit ACE2-RBD interaction, and anti-Spike IgG, IgA, and IgM antibodies was quantified by ELISA. In addition, specific memory B and T cells were quantified by flow cytometry. Results The level of specific MBCs, and isotypes, in the IgG−MBC− group was lower compared to that found in IgG−MBC+ (p = 0.0001) and IgG+MBC+ (p < 0.0001) groups, respectively. ACE2-RBD neutralizing antibodies and anti-S IgG antibodies were at lower levels in the IgG−MBC−group after the vaccine. Specific MBCs directly correlated with specific CD4+ T cells (although not significant, p = 0.065), while no correlation was found with specific CD8+ T cells (p = 0.156) after the vaccine. In parallel, ACE2-RBD neutralizing antibodies only positively correlated with specific CD4+ T cells (p = 0.034). Conclusion IgG−MBC− individuals showed the worst humoral and cellular responses, both in frequency and magnitude, after vaccination. Individuals whose antibodies wane and become undetectable after a given period of time post vaccination and show no specific MBCs are less protected and hence are good candidates for boosting vaccine. On the other hand, seronegative individuals with specific MBC showed faster and higher responses compared to the IgG−MBC− group.
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Affiliation(s)
- Alejandro Vallejo
- Laboratory of Immunovirology, Department of Infectious Diseases, Ramon y Cajal Institute for Health Investigation (IRyCIS), University Hospital Ramón y Cajal, Madrid, Spain
- *Correspondence: Alejandro Vallejo,
| | - Pilar Vizcarra
- Department of Infectious Diseases, Ramon y Cajal Institute for Health Investigation (IRyCIS), University Hospital Ramón y Cajal, Madrid, Spain
| | - Adrián Martín-Hondarza
- Laboratory of Immunovirology, Department of Infectious Diseases, Ramon y Cajal Institute for Health Investigation (IRyCIS), University Hospital Ramón y Cajal, Madrid, Spain
| | - Sandra Gómez-Maldonado
- Department of Infectious Diseases, Ramon y Cajal Institute for Health Investigation (IRyCIS), University Hospital Ramón y Cajal, Madrid, Spain
| | - Johannes Haemmerle
- Department of Prevention of Occupational Risks, University Hospital Ramón y Cajal, Madrid, Spain
| | - Héctor Velasco
- Laboratory of Immunovirology, Department of Infectious Diseases, Ramon y Cajal Institute for Health Investigation (IRyCIS), University Hospital Ramón y Cajal, Madrid, Spain
| | - José L. Casado
- Department of Infectious Diseases, Ramon y Cajal Institute for Health Investigation (IRyCIS), University Hospital Ramón y Cajal, Madrid, Spain
- José L. Casado,
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Casado JL, Vizcarra P, Haemmerle J, Velasco H, Martín-Hondarza A, Rodríguez-Domínguez MJ, Velasco T, Martín S, Romero-Hernández B, Fernández-Escribano M, Vallejo A. Pre-existing T cell immunity determines the frequency and magnitude of cellular immune response to two doses of mRNA vaccine against SARS-CoV-2. Vaccine X 2022; 11:100165. [PMID: 35529539 PMCID: PMC9057925 DOI: 10.1016/j.jvacx.2022.100165] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Revised: 03/31/2022] [Accepted: 04/25/2022] [Indexed: 01/02/2023] Open
Abstract
Lack of CD4 T-cell response to first/second dose of mRNA vaccine was observed in 21% and 12% of health care workers (HCWs). T-cell response was greater in frequency/magnitude in HCWs with pre-existing immunity, due due to infection or cross-reactivity. Pre-existing immunity correlated with the magnitude of specific antibodies production after vaccination.
Little is known about the factors associated with lack of T-cell response to mRNA vaccines against SARS-CoV-2. In a prospective cohort of 61 health care workers (HCWs), 21% and 16% after the first dose of mRNA BNT162b vaccine, and 12% and 7% after the second dose, showed lack of CD4+ and CD8+ T-cell response, respectively. Pre-existing T-cell immunity, due to past infection (46%) or cross-reactive cellular response (26%), was significantly associated with T-cell response in frequency (CD4+ T-cell, 100% vs 82% after two doses; p = 0.049) and in the magnitude of T-cell response during follow up. Furthermore, baseline CD4+ T-cell correlated positively with the titer of specific IgG-antibodies after first and second vaccine dose. Our data demonstrate that cross-reactive T-cells correlate with a better cellular response as well as an enhanced humoral response, and we confirm the close correlation of humoral and cellular response after mRNA vaccination.
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Affiliation(s)
- José L. Casado
- Department of Infectious Diseases, Hospital Universitario Ramon y Cajal, Madrid, Spain
- Corresponding authors at: Department of Infectious Diseases, Hospital Universitario Ramón y Cajal, Ctra Colmenar Km 9, 28034 Madrid, Spain (J.L. Casado). Laboratory of Immunovirology, Department of Infectious Diseases, Instituto Ramon y Cajal de Investigaciones Sanitarias (IRyCIS), Hospital Universitario Ramon y Cajal, Ctra Colmenar Km 9, 28034 Madrid, Spain (A. Vallejo).
| | - Pilar Vizcarra
- Department of Infectious Diseases, Hospital Universitario Ramon y Cajal, Madrid, Spain
| | - Johannes Haemmerle
- Department of Prevention of Occupational Risks, Hospital Universitario Ramon y Cajal, Madrid, Spain
| | - Héctor Velasco
- Laboratory of Immunovirology, Department of Infectious Diseases, Health Research Institute Ramon y Cajal (IRyCIS), Hospital Universitario Ramon y Cajal, Madrid, Spain
| | - Adrián Martín-Hondarza
- Laboratory of Immunovirology, Department of Infectious Diseases, Health Research Institute Ramon y Cajal (IRyCIS), Hospital Universitario Ramon y Cajal, Madrid, Spain
| | - Mario J. Rodríguez-Domínguez
- Department of Microbiology, Health Research Institute Ramon y Cajal (IRyCIS), CIBERESP, Hospital Universitario Ramon y Cajal, Madrid, Spain
| | - Tamara Velasco
- Department of Infectious Diseases, Hospital Universitario Ramon y Cajal, Madrid, Spain
| | - Sara Martín
- Department of Infectious Diseases, Hospital Universitario Ramon y Cajal, Madrid, Spain
| | - Beatriz Romero-Hernández
- Department of Microbiology, Health Research Institute Ramon y Cajal (IRyCIS), CIBERESP, Hospital Universitario Ramon y Cajal, Madrid, Spain
| | | | - Alejandro Vallejo
- Department of Infectious Diseases, Hospital Universitario Ramon y Cajal, Madrid, Spain
- Laboratory of Immunovirology, Department of Infectious Diseases, Health Research Institute Ramon y Cajal (IRyCIS), Hospital Universitario Ramon y Cajal, Madrid, Spain
- Corresponding authors at: Department of Infectious Diseases, Hospital Universitario Ramón y Cajal, Ctra Colmenar Km 9, 28034 Madrid, Spain (J.L. Casado). Laboratory of Immunovirology, Department of Infectious Diseases, Instituto Ramon y Cajal de Investigaciones Sanitarias (IRyCIS), Hospital Universitario Ramon y Cajal, Ctra Colmenar Km 9, 28034 Madrid, Spain (A. Vallejo).
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Doering C, Carini F, Sato M, Howard BJ, Harbottle AR, Brown J, Twining J, Velasco H. Updated soil to fruit concentration ratios for radiocaesium compiled under the IAEA MODARIA II Programme. J Radiol Prot 2022; 42:020511. [PMID: 35506679 DOI: 10.1088/1361-6498/ac6046] [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] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Accepted: 03/23/2022] [Indexed: 06/14/2023]
Abstract
Under the International Atomic Energy Agency (IAEA) Modelling and Data for Radiological Impact Assessments (MODARIA II) Programme, Working Group 4 activities included collating radionuclide transfer data from Japan following the Fukushima Daiichi Nuclear Power Plant accident and separately collating concentration ratio (CR) data for root uptake of radionuclides by crops grown in tropical and arid climates. In this paper, the newly compiled radiocaesium CR data for fruit from Japan, tropical and arid climates have been combined with the data originally compiled for the IAEA Technical Reports Series No. 472 (TRS 472) and additional data identified from the literature to produce an enhanced MODARIA II dataset of fruit radiocaesium CR values. Statistical analysis of the MODARIA II dataset by climate class (based on the Köppen-Geiger climate classification) indicated that the CR values for tropical climates were significantly higher (p< 0.05) than those for arid, temperate and cold climates. Statistical analysis of the MODARIA II dataset by soil group (based on soil texture) indicated that the CR values for coral sand soil (tropical climates only) and organic soil (temperate climates only) were significantly higher (p< 0.05) than those for the clay, loam and sand soil groups. Statistical analysis of the MODARIA II dataset by plant group (based on plant morphology) indicated that the CR values for non-woody trees (tropical climate bias) were significantly higher (p< 0.05) than those for herbaceous plants, shrubs and woody trees. Comparison of the MODARIA II dataset with original TRS 472 values showed only small changes in the fruit radiocaesium CR values for herbaceous plants and shrubs in temperate climates. There was a decrease in the CR values for woody trees in temperate climate across all soil groups. There was also a decrease in the CR values for tropical climates for all comparable soil groups.
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Affiliation(s)
- C Doering
- Environmental Research Institute of the Supervising Scientist, Darwin, Australia
| | - F Carini
- Università Cattolica del Sacro Cuore, Piacenza, Italy
| | - M Sato
- Faculty of Food and Agriculture, Fukushima University, Fukushima, Japan
| | - B J Howard
- Centre for Ecology and Hydrology, Lancaster, United Kingdom
- Division of Agricultural and Environmental Sciences, University of Nottingham, Nottingham, United Kingdom
| | | | - J Brown
- International Atomic Energy Agency, Vienna, Austria
| | - J Twining
- Austral Radioecology, Sydney, Australia
| | - H Velasco
- GEA-Instituto de Matemática Aplicada San Luis (IMASL), Universidad Nacional de San Luis, Consejo Nacional de Investigaciones Científicas y Técnicas., San Luis, Argentina
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Cortés A, Casado JL, Longo F, Serrano JJ, Saavedra C, Velasco H, Martin A, Chamorro J, Rosero D, Fernández M, Gion M, Martínez Jáñez N, Soria Rivas A, Alonso Gordoa T, Martínez Delfrade Í, Lage Y, López Miranda E, Olmedo ME, Reguera Puertas P, Gajate P, Molina Cerrillo J, Guerra Alia E, Fuentes Mateos R, Romero B, Rodríguez-Domínguez MJ, Vallejo A, Carrato A. Limited T cell response to SARS-CoV-2 mRNA vaccine among patients with cancer receiving different cancer treatments. Eur J Cancer 2022; 166:229-239. [PMID: 35316750 PMCID: PMC8885286 DOI: 10.1016/j.ejca.2022.02.017] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2022] [Revised: 02/13/2022] [Accepted: 02/18/2022] [Indexed: 01/06/2023]
Abstract
INTRODUCTION Patients with cancer (PC) are at high risk of acquiring COVID-19 and can develop more serious complications. Deeper understanding of vaccines immunogenicity in this population is crucial for adequately planning vaccines programs. The ONCOVac study aimed to comprehensively assess the immunogenicity of mRNA-1273 vaccine in terms of humoral and cellular response. METHODS We conducted a prospective, single-center study including patients with solid tumours treated with cyclin-dependent kinases 4 and 6 inhibitors (CDK4/6i), immunotherapy (IT) or chemotherapy (CT). Patients were enrolled previously to vaccination with mRNA-1273. We also involved health care workers (HCW) to serve as a control group. We took blood samples before first dose administration (BL), after first dose (1D), and after second dose (2D). The primary objective was to compare the rate and magnitude of T cell response after second dose whereas safety and humoral response were defined as secondary objectives. We also collected patient reported outcomes after both the first and second vaccine dose and a six-month follow-up period to diagnose incident COVID-19 cases was planned. RESULTS The rate of specific anti-S serologic positivity (anti-S IgG cut-off point at 7,14 BAU/mL) was significantly higher in HCW compared to PC after 1D (100% versus 83.8%; p = 0.04), but similar after 2D (100% versus 95.8%; p = 0.5). This difference after 1D was driven by PC treated with CT (100% versus 64.5%; p = 0.001). Cellular response after 2D was significantly lower in PC than in HCW for both CD4+ (91.7% versus 59.7%; p = 0.001) and CD8+ (94.4% versus 55.6%; p < 0.001) T cells. We found a difference on pre-existing CD4+ T cell response in HCW comparing to PC (36% and 17%, p = 0.03); without difference in pre-existing CD8+ T cell response (31% and 23%, p = 0.5). After excluding patients with pre-existing T cell response, PC achieved even lower CD4+ (50.9% versus 95.5%, p < 0.001) and CD8+ (45.5% versus 95.5%, p < 0.001) T cell response compared with HCW. Regarding safety, PC reported notably more adverse events than HCW (96.6% versus 69.2%, p < 0.001). CONCLUSION We demonstrated that PC showed a similar humoral response but a lower T cell response following two doses of mRNA-1273 vaccination. Further studies are needed to complement our results and determine the implication of low T cell response on clinical protection of PC against COVID-19.
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Affiliation(s)
- Alfonso Cortés
- Medical Oncology Department, Ramón y Cajal University Hospital, Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), Madrid, Spain
| | - José L Casado
- Infectious Disease Department, Ramón y Cajal University Hospital, Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), Madrid, Spain
| | - Federico Longo
- Medical Oncology Department, Ramón y Cajal University Hospital, Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), Madrid, Spain; Centro de Investigación Biomédica en Red (CIBERONC), Alcalá de Henares University, Madrid, Spain
| | - Juan J Serrano
- Medical Oncology Department, Ramón y Cajal University Hospital, Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), Madrid, Spain
| | - Cristina Saavedra
- Medical Oncology Department, Ramón y Cajal University Hospital, Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), Madrid, Spain
| | - Héctor Velasco
- Laboratory of Immunovirology, Infectious Diseases Department, Ramón y Cajal University Hospital, Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), Madrid, Spain
| | - Adrián Martin
- Laboratory of Immunovirology, Infectious Diseases Department, Ramón y Cajal University Hospital, Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), Madrid, Spain
| | - Jesús Chamorro
- Medical Oncology Department, Ramón y Cajal University Hospital, Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), Madrid, Spain
| | - Diana Rosero
- Medical Oncology Department, Ramón y Cajal University Hospital, Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), Madrid, Spain
| | - María Fernández
- Medical Oncology Department, Ramón y Cajal University Hospital, Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), Madrid, Spain
| | - María Gion
- Medical Oncology Department, Ramón y Cajal University Hospital, Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), Madrid, Spain
| | - Noelia Martínez Jáñez
- Medical Oncology Department, Ramón y Cajal University Hospital, Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), Madrid, Spain
| | - Ainara Soria Rivas
- Medical Oncology Department, Ramón y Cajal University Hospital, Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), Madrid, Spain
| | - Teresa Alonso Gordoa
- Medical Oncology Department, Ramón y Cajal University Hospital, Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), Madrid, Spain
| | - Íñigo Martínez Delfrade
- Medical Oncology Department, Ramón y Cajal University Hospital, Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), Madrid, Spain
| | - Yolanda Lage
- Medical Oncology Department, Ramón y Cajal University Hospital, Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), Madrid, Spain
| | - Elena López Miranda
- Medical Oncology Department, Ramón y Cajal University Hospital, Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), Madrid, Spain
| | - María E Olmedo
- Medical Oncology Department, Ramón y Cajal University Hospital, Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), Madrid, Spain
| | - Pablo Reguera Puertas
- Medical Oncology Department, Ramón y Cajal University Hospital, Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), Madrid, Spain
| | - Pablo Gajate
- Medical Oncology Department, Ramón y Cajal University Hospital, Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), Madrid, Spain
| | - Javier Molina Cerrillo
- Medical Oncology Department, Ramón y Cajal University Hospital, Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), Madrid, Spain
| | - Eva Guerra Alia
- Medical Oncology Department, Ramón y Cajal University Hospital, Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), Madrid, Spain
| | - Raquel Fuentes Mateos
- Medical Oncology Department, Ramón y Cajal University Hospital, Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), Madrid, Spain
| | - Beatriz Romero
- Microbiology Department, Ramón y Cajal University Hospital, Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), Madrid, Spain
| | - Mario J Rodríguez-Domínguez
- Microbiology Department, Ramón y Cajal University Hospital, Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), Madrid, Spain; Centro de Investigación Biomédica en Red (CIBER) en Epidemiología y Salud Pública, Spain
| | - Alejandro Vallejo
- Laboratory of Immunovirology, Infectious Diseases Department, Ramón y Cajal University Hospital, Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), Madrid, Spain.
| | - Alfredo Carrato
- Medical Oncology Department, Ramón y Cajal University Hospital, Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), Madrid, Spain; Centro de Investigación Biomédica en Red (CIBERONC), Alcalá de Henares University, Madrid, Spain.
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Vallejo A, Martín-Hondarza A, Gómez S, Velasco H, Vizcarra P, Haemmerle J, Casado JL. Cellular Responses to Membrane and Nucleocapsid Viral Proteins Are Also Boosted After SARS-CoV-2 Spike mRNA Vaccination in Individuals With Either Past Infection or Cross-Reactivity. Front Microbiol 2022; 12:812729. [PMID: 35222312 PMCID: PMC8874124 DOI: 10.3389/fmicb.2021.812729] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Accepted: 12/28/2021] [Indexed: 12/22/2022] Open
Abstract
SARS-CoV-2 spike mRNA vaccines have shown remarkable clinical efficacy in the general population, although the nature of T-cell priming is not fully understood. We performed longitudinal spike-, membrane-, and nucleocapsid-specific T-cell analysis in individuals with past infection and infection-naïve individuals with cross-reactivity. We found an additional enhancement of T-cell response to the structural membrane (M) and nucleocapsid (N) SARS-CoV-2 proteins after mRNA vaccine in these individuals. Thus, despite the spike-specific response, we found that the first dose of the vaccine boosted a significant CD8 cell response to M and N proteins, whereas no cellular response to those proteins was found in infection-naïve individuals without pre-existing cross-reactivity who were tested for eventual asymptomatic infection. These findings highlight the additional benefit of mRNA vaccines as broad boosters of cellular responses to different viral epitopes in these individuals and suggest extended protection to other viral variants.
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Affiliation(s)
- Alejandro Vallejo
- Laboratory of Immunovirology, Health Research Institute Ramón y Cajal (IRyCIS), University Hospital Ramón y Cajal, Madrid, Spain
| | - Adrián Martín-Hondarza
- Laboratory of Immunovirology, Health Research Institute Ramón y Cajal (IRyCIS), University Hospital Ramón y Cajal, Madrid, Spain
| | - Sandra Gómez
- Department of Infectious Diseases, Health Research Institute Ramón y Cajal (IRyCIS), University Hospital Ramón y Cajal, Madrid, Spain
| | - Héctor Velasco
- Laboratory of Immunovirology, Health Research Institute Ramón y Cajal (IRyCIS), University Hospital Ramón y Cajal, Madrid, Spain
| | - Pilar Vizcarra
- Department of Infectious Diseases, Health Research Institute Ramón y Cajal (IRyCIS), University Hospital Ramón y Cajal, Madrid, Spain
| | - Johannes Haemmerle
- Department of Prevention of Occupational Risks, Health Research Institute Ramón y Cajal (IRyCIS), University Hospital Ramón y Cajal, Madrid, Spain
| | - José L. Casado
- Department of Infectious Diseases, Health Research Institute Ramón y Cajal (IRyCIS), University Hospital Ramón y Cajal, Madrid, Spain
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Casado JL, Moraga E, Vizcarra P, Velasco H, Martín-Hondarza A, Haemmerle J, Gómez S, Quereda C, Vallejo A. Expansion of CD56 dimCD16 neg NK Cell Subset and Increased Inhibitory KIRs in Hospitalized COVID-19 Patients. Viruses 2021; 14:v14010046. [PMID: 35062250 PMCID: PMC8780522 DOI: 10.3390/v14010046] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Revised: 12/17/2021] [Accepted: 12/24/2021] [Indexed: 01/08/2023] Open
Abstract
Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV-2) infection induces elevated levels of inflammatory cytokines, which are mainly produced by the innate response to the virus. The role of NK cells, which are potent producers of IFN-γ and cytotoxicity, has not been sufficiently studied in the setting of SARS-CoV-2 infection. We confirmed a different distribution of NK cell subsets in hospitalized COVID-19 patients despite their NK cell deficiency. The impairment of this innate defense is mainly focused on the cytotoxic capacity of the CD56dim NK cells. On the one hand, we found an expansion of the CD56dimCD16neg NK subset, lower cytotoxic capacities, and high frequencies of inhibitory 2DL1 and 2DL1/S1 KIR receptors in COVID-19 patients. On the other hand, the depletion of CD56dimCD16dim/bright NK cell subsets, high cytotoxic capacities, and high frequencies of inhibitory 2DL1 KIR receptors were found in COVID-19 patients. In contrast, no differences in the distribution of CD56bright NK cell subsets were found in this study. These alterations in the distribution and phenotype of NK cells might enhance the impairment of this crucial innate line of defense during COVID-19 infection.
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Affiliation(s)
- José L. Casado
- Department of Infectious Diseases, Ramón y Cajal Institute for Health Research (IRyCIS), University Hospital Ramón y Cajal, 28034 Madrid, Spain; (E.M.); (P.V.); (H.V.); (A.M.-H.); (S.G.); (C.Q.)
- Correspondence: (J.L.C.); (A.V.)
| | - Elisa Moraga
- Department of Infectious Diseases, Ramón y Cajal Institute for Health Research (IRyCIS), University Hospital Ramón y Cajal, 28034 Madrid, Spain; (E.M.); (P.V.); (H.V.); (A.M.-H.); (S.G.); (C.Q.)
- Laboratory of Immunovirology, Ramón y Cajal Institute for Health Research, University Hospital Ramón y Cajal, 28034 Madrid, Spain
| | - Pilar Vizcarra
- Department of Infectious Diseases, Ramón y Cajal Institute for Health Research (IRyCIS), University Hospital Ramón y Cajal, 28034 Madrid, Spain; (E.M.); (P.V.); (H.V.); (A.M.-H.); (S.G.); (C.Q.)
| | - Héctor Velasco
- Department of Infectious Diseases, Ramón y Cajal Institute for Health Research (IRyCIS), University Hospital Ramón y Cajal, 28034 Madrid, Spain; (E.M.); (P.V.); (H.V.); (A.M.-H.); (S.G.); (C.Q.)
- Laboratory of Immunovirology, Ramón y Cajal Institute for Health Research, University Hospital Ramón y Cajal, 28034 Madrid, Spain
| | - Adrián Martín-Hondarza
- Department of Infectious Diseases, Ramón y Cajal Institute for Health Research (IRyCIS), University Hospital Ramón y Cajal, 28034 Madrid, Spain; (E.M.); (P.V.); (H.V.); (A.M.-H.); (S.G.); (C.Q.)
- Laboratory of Immunovirology, Ramón y Cajal Institute for Health Research, University Hospital Ramón y Cajal, 28034 Madrid, Spain
| | - Johannes Haemmerle
- Department of Prevention of Occupational Risks, University Hospital Ramón y Cajal, 28034 Madrid, Spain;
| | - Sandra Gómez
- Department of Infectious Diseases, Ramón y Cajal Institute for Health Research (IRyCIS), University Hospital Ramón y Cajal, 28034 Madrid, Spain; (E.M.); (P.V.); (H.V.); (A.M.-H.); (S.G.); (C.Q.)
| | - Carmen Quereda
- Department of Infectious Diseases, Ramón y Cajal Institute for Health Research (IRyCIS), University Hospital Ramón y Cajal, 28034 Madrid, Spain; (E.M.); (P.V.); (H.V.); (A.M.-H.); (S.G.); (C.Q.)
| | - Alejandro Vallejo
- Department of Infectious Diseases, Ramón y Cajal Institute for Health Research (IRyCIS), University Hospital Ramón y Cajal, 28034 Madrid, Spain; (E.M.); (P.V.); (H.V.); (A.M.-H.); (S.G.); (C.Q.)
- Laboratory of Immunovirology, Ramón y Cajal Institute for Health Research, University Hospital Ramón y Cajal, 28034 Madrid, Spain
- Correspondence: (J.L.C.); (A.V.)
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Velasco H, Anjos RM. A review of 137Cs and 40K soil-to-plant transfer factors in tropical plants. J Environ Radioact 2021; 235-236:106650. [PMID: 34058642 DOI: 10.1016/j.jenvrad.2021.106650] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Revised: 05/11/2021] [Accepted: 05/14/2021] [Indexed: 06/12/2023]
Abstract
In this work we critically assess the soil-to-plant transfer factors (TF) for 137Cs and 40K in edible fleshy organs of tropical plants that are often components of the human diet. Radionuclide concentrations in soil and plants were obtained from previous investigations developed in Brazil, after the Goiânia radiological accident occurred in 1987. Transfer factors were determined in specific plant compartments (main root, main stem, bark, old and new branches, twig, old and new leaves, mature and green edible organs) of tropical species such as lemon (Citrus aurantifolia), orange (Citrus sinensis), guava (Psidium guajava), chili pepper (Capsicum frutescens), pomegranate (Punica granatum), papaya (Carica papaya), banana (Musa paradisíaca), and manioc (Manihot esculenta). For 137Cs, soil-to-fruit transfer factor ranged from 0.80 × 10-2 (banana) to 3.65 × 10-1 (pomegranate); for 40K, this factor was from 4.42 × 10-1 (orange) to 1.74 (chili pepper). Considering all the plant compartments analysed, the transfer factors for 40K are between 24.5 (guava) and 90.5 (papaya) times higher than for 137Cs. For both radionuclides, considerable differences in soil-to-plant transfer were found when new growing parts of the plant (green edible organ, leaf, and twig) are considered with respect to those older parts (mature edible organ, old leaf and branches). Considering all the species analyzed, the relationship TF(40K)/TF(137Cs) does not seem to follow a characteristic pattern. However, if we compare the value of this relationship for two organs of the same plant, the result is approximately constant, regardless of the species considered. This confirms earlier evidence that both radionuclides are similarly distributed in the different organs of the studied species. The differences in the transfer factors according to the ripening status of edible organs must be particularly considered when estimating the dose from ingestion of fruits and their derivatives in dose assessment models.
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Affiliation(s)
- H Velasco
- GEA - Instituto de Matemática Aplicada San Luis (IMASL), Universidad Nacional de San Luis, Consejo Nacional de Investigaciones Científicas y Técnicas, Ej. de los Andes 950, D5700HHW, San Luis, Argentina.
| | - R M Anjos
- LARA - Laboratório de Radioecologia e Alterações Ambientais (LARA), Instituto de Física, Universidade Federal Fluminense, Av. Gal Milton Tavares de Souza, s/no, Gragoatá, 24210-340, Niterói,RJ, Brazil
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Velasco H. Modifications in the gamma dose rate in air due to downward and lateral mobility of 137Cs in the soil. J Environ Radioact 2019; 198:159-164. [PMID: 30616071 DOI: 10.1016/j.jenvrad.2018.12.030] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Revised: 12/28/2018] [Accepted: 12/30/2018] [Indexed: 06/09/2023]
Abstract
137Cs can be an important environmental contaminant due to fallout from nuclear reactor accidents and atomic weapons testing. Its contribution to the air gamma dose rate at 1 m height above contaminated ground depends on the soil inventory, the migration processes along the soil profile and possible modifications in the spatial distribution. In this paper the diffusion-convection equation is used to approach the 137Cs soil vertical migration transport and standard dose rate factors are jointly applied for estimating the air dose rate. In order to calculate the temporal reduction of the external radiation, an empirical attenuation factor is used and its coefficients are analyzed in terms of the effective diffusion coefficient and downward migration rates. Additionally, it is analyze the corrections that should be introduced in dose rate values attributable to soil redistribution processes. If these processes, natural or as a consequence of human activities, are not taken into account, both the air dose rate values and the attenuation period can be noticeably under or overestimated.
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Affiliation(s)
- H Velasco
- GEA - Grupo de Estudios Ambientales, Instituto de Matemática Aplicada San Luis (IMASL), Universidad Nacional de San Luis, Consejo Nacional de Investigaciones Científicas y Técnicas, CCT-San Luis, San Luis, Argentina.
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Velasco H, Astorga RT, Joseph D, Antoine JS, Mabit L, Toloza A, Dercon G, Walling DE. Adapting the Caesium-137 technique to document soil redistribution rates associated with traditional cultivation practices in Haiti. J Environ Radioact 2018; 183:7-16. [PMID: 29274798 DOI: 10.1016/j.jenvrad.2017.12.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2017] [Revised: 12/13/2017] [Accepted: 12/14/2017] [Indexed: 06/07/2023]
Abstract
Large-scale deforestation, intensive land use and unfavourable rainfall conditions are responsible for significant continuous degradation of the Haitian uplands. To develop soil conservation strategies, simple and cost-effective methods are needed to assess rates of soil loss from farmland in Haiti. The fallout radionuclide caesium-137 (137Cs) provides one such means of documenting medium-term soil redistribution rates. In this contribution, the authors report the first use in Haiti of 137Cs measurements to document soil redistribution rates and the associated pattern of erosion/sedimentation rates along typical hillslopes within a traditional upland Haitian farming area. The local 137Cs reference inventory, measured at an adjacent undisturbed flat area, was 670 Bq m-2 (SD = 100 Bq m-2, CV = 15%, n = 7). Within the study area, where cultivation commenced in 1992 after deforestation, three representative downslope transects were sampled. These were characterized by 137Cs inventories ranging from 190 to 2200 Bq m-2. Although, the study area was cultivated by the local farmers, the 137Cs depth distributions obtained from the area differed markedly from those expected from a cultivated area. They showed little evidence of tillage mixing within the upper part of the soil or, more particularly, of the near-uniform activities normally associated with the plough layer or cultivation horizon. They were very similar to that found at the reference site and were characterized by high 137Cs activities at the surface and much lower activities at greater depths. This situation is thought to reflect the traditional manual tillage practices which cause limited disturbance and mixing of the upper part of the soil. It precluded the use of the conversion models normally used to estimate soil redistribution rates from 137Cs measurements on cultivated soils and the Diffusion and Migration conversion model frequently used for uncultivated soils was modified for application to the cultivated soils of the study area, in order to take account of the unusual local conditions. The model was also modified to take account of the fact that cultivation in the study area commenced in 1992, rather than predating the period of weapons test fallout which extended from the mid 1950s to the 1970s. Erosion rates on the upper parts of the hillside involved in the study were found to be relatively high and ca. -23 t ha-1 y-1 with low spatial variability. In the lower, flatter areas at the bottom of the slope, deposition occurred. Deposition rates were characterized by high spatial variability, ranging from 6.0 to 71 t ha-1 y-1. Soil redistribution rates of this magnitude are a cause for concern and there is an urgent need to implement soil conservation measures to ensure the longer-term sustainability of the local agricultural practices.
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Affiliation(s)
- H Velasco
- GEA - Grupo de Estudios Ambientales - Instituto de Matemática Aplicada San Luis (IMASL) - Universidad Nacional de San Luis, Consejo Nacional de Investigaciones Científicas y Técnicas, CCT-San Luis, San Luis, Argentina.
| | - R Torres Astorga
- GEA - Grupo de Estudios Ambientales - Instituto de Matemática Aplicada San Luis (IMASL) - Universidad Nacional de San Luis, Consejo Nacional de Investigaciones Científicas y Técnicas, CCT-San Luis, San Luis, Argentina
| | - D Joseph
- Direction des Ressources Forestières et des Sols (DRFS). Ministère de l'Agriculture, des Ressources Naturelles et du Développement Rural, Port-au-Prince, Haiti; Faculté d'Agronomie et de Médecine Vétérinaire (FAMV), Port-au-Prince, Haiti
| | - J S Antoine
- Direction des Ressources Forestières et des Sols (DRFS). Ministère de l'Agriculture, des Ressources Naturelles et du Développement Rural, Port-au-Prince, Haiti; Faculté d'Agronomie et de Médecine Vétérinaire (FAMV), Port-au-Prince, Haiti
| | - L Mabit
- Soil and Water Management & Crop Nutrition Laboratory, Joint Division of Nuclear Techniques in Food and Agriculture, International Atomic Energy Agency, Austria
| | - A Toloza
- Soil and Water Management & Crop Nutrition Laboratory, Joint Division of Nuclear Techniques in Food and Agriculture, International Atomic Energy Agency, Austria
| | - G Dercon
- Soil and Water Management & Crop Nutrition Laboratory, Joint Division of Nuclear Techniques in Food and Agriculture, International Atomic Energy Agency, Austria
| | - Des E Walling
- Geography, College of Life and Environmental Sciences, University of Exeter, Exeter, EX4 4RJ, UK
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Cid AS, Anjos RM, Zamboni CB, Cardoso R, Muniz M, Corona A, Valladares DL, Kovacs L, Macario K, Perea D, Goso C, Velasco H. Na, K, Ca, Mg, and U-series in fossil bone and the proposal of a radial diffusion-adsorption model of uranium uptake. J Environ Radioact 2014; 136:131-139. [PMID: 24953228 DOI: 10.1016/j.jenvrad.2014.05.018] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2014] [Revised: 05/20/2014] [Accepted: 05/23/2014] [Indexed: 06/03/2023]
Abstract
Fossil bones are often the only materials available for chronological reconstruction of important archeological sites. However, since bone is an open system for uranium, it cannot be dated directly and therefore it is necessary to develop models for the U uptake. Hence, a radial diffusion-adsorption (RDA) model is described. Unlike the classic diffusion-adsorption (D-A) model, RDA uses a cylindrical geometry to describe the U uptake in fossil bones. The model was applied across a transverse section of a tibia of an extinct megamammal Macrauchenia patachonica from the La Paz Local Fauna, Montevideo State, Uruguay. Measurements of spatial distribution of Na, K, Ca, and Mg were also performed by neutron activation analysis (NAA). Gamma-ray spectrometric U-series dating was applied to determine the age of the bone sample. From U concentration profile, it was possible to observe the occurrence of a relatively slow and continuous uranium uptake under constant conditions that had not yet reached equilibrium, since the uranium distribution is a ∪-shaped closed-system. Predictions of the RDA model were obtained for a specific geochemical scenario, indicating that the effective diffusion coefficient D/R in this fossil bone is (2.4 ± 0.6)10(-12) cm(2)s(-1). Mean values of Na, K, Ca, and Mg contents along the radial line of the fossil tibia are consistent with the expected behavior for spatial distributions of these mineral elements across a modern bone section. This result indicates that the fossil tibia may have its mineral structure preserved.
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Affiliation(s)
- A S Cid
- LARA - Laboratório de Radioecologia e Alterações Ambientais, Instituto de Física, Universidade Federal Fluminense, Av. Gal Milton Tavares de Souza, S/N, Gragoatá, 24210-346, Niterói, RJ, Brazil
| | - R M Anjos
- LARA - Laboratório de Radioecologia e Alterações Ambientais, Instituto de Física, Universidade Federal Fluminense, Av. Gal Milton Tavares de Souza, S/N, Gragoatá, 24210-346, Niterói, RJ, Brazil.
| | - C B Zamboni
- Instituto de Pesquisas Energéticas e Nucleares (IPEN/CNEN), Centro do Reator de Pesquisa (CRPq), Av. Lineu Prestes 2242 - Cidade Universitária, 05508-000, São Paulo, SP, Brazil
| | - R Cardoso
- LARA - Laboratório de Radioecologia e Alterações Ambientais, Instituto de Física, Universidade Federal Fluminense, Av. Gal Milton Tavares de Souza, S/N, Gragoatá, 24210-346, Niterói, RJ, Brazil
| | - M Muniz
- LARA - Laboratório de Radioecologia e Alterações Ambientais, Instituto de Física, Universidade Federal Fluminense, Av. Gal Milton Tavares de Souza, S/N, Gragoatá, 24210-346, Niterói, RJ, Brazil
| | - A Corona
- Departamento de Evolución de Cuencas, Facultad de Ciencias, UDELAR, Iguá 4225, Montevideo 11400, Uruguay
| | - D L Valladares
- GEA - Instituto de Matemática Aplicada San Luis (IMASL), Universidad Nacional de San Luis, CCT-San Luis CONICET, Ej. de los Andes 950, D5700HHW, San Luis, Argentina
| | - L Kovacs
- Instituto de Pesquisas Energéticas e Nucleares (IPEN/CNEN), Centro do Reator de Pesquisa (CRPq), Av. Lineu Prestes 2242 - Cidade Universitária, 05508-000, São Paulo, SP, Brazil
| | - K Macario
- LARA - Laboratório de Radioecologia e Alterações Ambientais, Instituto de Física, Universidade Federal Fluminense, Av. Gal Milton Tavares de Souza, S/N, Gragoatá, 24210-346, Niterói, RJ, Brazil
| | - D Perea
- Departamento de Evolución de Cuencas, Facultad de Ciencias, UDELAR, Iguá 4225, Montevideo 11400, Uruguay
| | - C Goso
- Departamento de Evolución de Cuencas, Facultad de Ciencias, UDELAR, Iguá 4225, Montevideo 11400, Uruguay
| | - H Velasco
- GEA - Instituto de Matemática Aplicada San Luis (IMASL), Universidad Nacional de San Luis, CCT-San Luis CONICET, Ej. de los Andes 950, D5700HHW, San Luis, Argentina
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Lohaiza F, Velasco H, Juri Ayub J, Rizzotto M, Di Gregorio DE, Huck H, Valladares DL. Annual variation of (7)Be soil inventory in a semiarid region of central Argentina. J Environ Radioact 2014; 130:72-77. [PMID: 24487256 DOI: 10.1016/j.jenvrad.2014.01.006] [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] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2013] [Revised: 01/09/2014] [Accepted: 01/13/2014] [Indexed: 06/03/2023]
Abstract
Reliable information on environmental radionuclides atmospheric entrance, and their distribution along the soil profile, is a necessary condition for using these soil and sediment tracers to investigate key environmental processes. To address this need, (7)Be content in rainwater and the wet deposition in a semiarid region at San Luis Province, Argentina, were studied. Following these researches, in the same region, we have assessed the (7)Be content along a soil profile, during 2.5 years from September 2009 to January 2012. As expected, the specific activity values in soil samples in the wet period (November-April) were higher than in the dry period (May-October). During the investigated period (2009 - beginning 2012) and for all sampled points, the maximum value of the (7)Be specific activity (Bq kg(-1)) was measured at the surface level. A typical decreasing exponential function of (7)Be areal activity (Bq m(-2)) with soil mass depth (kg m(-2)) was found and the key distribution parameters were determined for each month. The minimum value of areal activity was 51 Bq m(-2) in August, and the maximum was 438 Bq m(-2) in February. The relaxation mass depth ranges from 2.9 kg m(-2) in March to 1.3 kg m(-2) in August. (7)Be wet deposition can explain in a very significant proportion the (7)Be inventory in soil. During the period of winds in the region (September and October), the (7)Be content in soil was greater than the expected contribution from wet deposition, situation that is compatible with a higher relative contribution of dry deposition at this period of the year.
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Affiliation(s)
- F Lohaiza
- Grupo de Estudios Ambientales, Instituto de Matemática Aplicada San Luis, Universidad Nacional de San Luis - CONICET, Ejército de los Andes 950, D5700HHW San Luis, Argentina
| | - H Velasco
- Grupo de Estudios Ambientales, Instituto de Matemática Aplicada San Luis, Universidad Nacional de San Luis - CONICET, Ejército de los Andes 950, D5700HHW San Luis, Argentina.
| | - J Juri Ayub
- Grupo de Estudios Ambientales, Instituto de Matemática Aplicada San Luis, Universidad Nacional de San Luis - CONICET, Ejército de los Andes 950, D5700HHW San Luis, Argentina
| | - M Rizzotto
- Grupo de Estudios Ambientales, Instituto de Matemática Aplicada San Luis, Universidad Nacional de San Luis - CONICET, Ejército de los Andes 950, D5700HHW San Luis, Argentina
| | - D E Di Gregorio
- Departamento de Física, Comisión Nacional de Energía Atómica, Av. Gral. Paz 1499, 1650 San Martín, Provincia de Buenos Aires, Argentina; Escuela de Ciencia y Tecnología, Universidad Nacional de San Martín, Martín de Irigoyen 3100, 1650 San Martín, Provincia de Buenos Aires, Argentina
| | - H Huck
- Departamento de Física, Comisión Nacional de Energía Atómica, Av. Gral. Paz 1499, 1650 San Martín, Provincia de Buenos Aires, Argentina; Escuela de Ciencia y Tecnología, Universidad Nacional de San Martín, Martín de Irigoyen 3100, 1650 San Martín, Provincia de Buenos Aires, Argentina
| | - D L Valladares
- Grupo de Estudios Ambientales, Instituto de Matemática Aplicada San Luis, Universidad Nacional de San Luis - CONICET, Ejército de los Andes 950, D5700HHW San Luis, Argentina
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Valladares DL, da Silva AAR, Lacerda T, Anjos RM, Rizzotto M, Velasco H, de Rosas JP, Tognelli G, Yoshimura EM, Ayub JJ. Using (222)Rn as a tracer of geodynamical processes in underground environments. Sci Total Environ 2014; 468-469:12-18. [PMID: 24012891 DOI: 10.1016/j.scitotenv.2013.08.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2013] [Revised: 07/19/2013] [Accepted: 08/03/2013] [Indexed: 06/02/2023]
Abstract
Radon levels in two old mines in San Luis, Argentina, were measured and analyzed, with the aim to assess the potential use of this radioactive noble gas as a tracer of geological processes in underground environments. La Carolina gold mine and Los Cóndores tungsten mine are today used as tourism mines. CR-39 nuclear track detectors were used for this purpose. Measurements were performed during both winter and summer seasons. The findings show that in these environments, significant radon concentrations are subject to large seasonal fluctuations, due to the strong dependence on natural ventilation with the outside temperature variations. For both mines, higher concentration values of (222)Rn were observed in summer than in winter; with an extreme ratio of 2.5 times between summer and winter seasons for Los Cóndores mine. The pattern of radon transport inside La Carolina mine revealed, contrary to what was believed, that this mine behaves as a system with two entrances located at different levels. However, this feature can only be observed in the winter season, when there is a marked difference between the inside and outside temperatures of the mine. In the case of Los Cóndores mine, the radon concentration pattern distribution is principally established by air current due to chimney-effect in summer and winter seasons. In both cases, the analyses of radon pattern distribution appear as a good method to trace air currents, and then localize unknown ducts, fissures or secondary tunnels in subterranean environments.
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Affiliation(s)
- D L Valladares
- GEA, Instituto de Matemática Aplicada San Luis (IMASL), Universidad Nacional de San Luis, Consejo Nacional de Investigaciones Científicas y Técnicas, Ej. de los Andes 950, D5700HHW San Luis, Argentina
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Cid AS, Anjos RM, Zamboni CB, Velasco H, Macario K, Rizzotto M, Medeiros IMA, Ayub JJ, Audicio P. Temporal evolution of ¹³⁷Cs⁺, K⁺ and Na⁺ in fruits of South American tropical species. Sci Total Environ 2013; 444:115-120. [PMID: 23268139 DOI: 10.1016/j.scitotenv.2012.11.092] [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] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2012] [Revised: 11/26/2012] [Accepted: 11/27/2012] [Indexed: 06/01/2023]
Abstract
Concentrations of (137)Cs, K and Na in fruits of lemon (Citrus limon B.) and of K and Na in fruits of coconut (Cocos nucifera L.) trees were measured by both gamma spectrometry and neutron activation analysis, with the aim to understand the behaviour of monovalent inorganic cations in tropical plants as well as the plant ability to store these elements. Similar amounts of K(+) were incorporated by lemon and coconut trees during the growth and ripening processes of its fruits. The K concentration decreased exponentially during the growth of lemons and coconuts, ranging from 13 to 25 g kg(-1) dry weight. The incorporation of Na(+) differed considerably between the plant species studied. The Na concentration increased linearly during the lemon growth period (0.04 to 0.70 g kg(-1) d.w.) and decreased exponentially during the coconut growth period (1.4 to 0.5 g kg(-1) d.w.). Even though radiocaesium is not an essential element to plants, our results have shown that (137)Cs incorporation to vegetable tissues is positively correlated to K distribution within the studied tropical plant species, suggesting that the two elements might be assimilated in a similar way, going through the biological cycle together. A mathematical model was developed from the experimental data allowing simulating the incorporation process of monovalent inorganic cations by the fruits of such tropical species. The agreement between the theoretical approach and the experimental values is satisfactory along fruit development.
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Affiliation(s)
- A S Cid
- LARA - Laboratório de Radioecologia, Instituto de Física, Universidade Federal Fluminense, Av. Gal Milton Tavares de Souza, s/no, Gragoatá, 24210-340 Niterói, RJ, Brazil
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Ayub JJ, Lohaiza F, Velasco H, Rizzotto M, Di Gregorio D, Huck H. Assessment of ⁷Be content in precipitation in a South American semi-arid environment. Sci Total Environ 2012; 441:111-116. [PMID: 23137975 DOI: 10.1016/j.scitotenv.2012.09.079] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2012] [Revised: 09/26/2012] [Accepted: 09/29/2012] [Indexed: 06/01/2023]
Abstract
There are two naturally occurring radiogenic isotopes of beryllium, ⁷Be and ¹⁰Be. These are produced when cosmic radiation interacts with oxygen and nitrogen in the atmosphere. After production, these radionuclides are input to ecosystems through wet and dry deposition. In recent years ⁷Be and ¹⁰Be have proved to be powerful tools for studying dynamic processes that occur on the surface of the earth. We measured the ⁷Be content in precipitation at a semiarid location in central Argentina. From November 2006 to March 2009, 68 precipitation events were collected. Measured ⁷Be content ranged from 0.7±0.4 Bq L⁻¹ to 3.2±0.7 Bq L⁻¹, with a mean of 1.7 Bq L⁻¹ ±0.6 Bq L⁻¹. Beryllium-7 content of rainfall did not show clear relationships with amount of rainfall (mm), mean intensity (mm h⁻¹) or duration (h⁻¹), or elapsed time between events (day). The general results indicate that for the typical range of precipitation there was no atmospheric washout and that the reload of the atmosphere is not a relevant factor, but when the amount of precipitation is very high washout may occur. On the other hand, when the ⁷Be content was measured during single rain events, a high content of this radionuclide was found to be associated with very low rainfall intensity (≈3 mm h⁻¹), this suggests that rain intensity could affect the ⁷Be content. Using all data, a good linear relationship between ⁷Be deposition and rain magnitude was obtained (r²=0.82, p<0.0001). Because of this, the slope of this linear regression equation may be applied as a tool for tracing environmental processes that affect the surface of the earth. We can do this by directly estimating erosion/sedimentation processes using ⁷Be or by estimating the input of ¹⁰Be in the environment with the aim to evaluate land degradation phenomena.
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Affiliation(s)
- J Juri Ayub
- Grupo de Estudios Ambientales, Instituto de Matemática Aplicada San Luis, Universidad Nacional de San Luis/CCT-San Luis-CONICET, San Luis, Argentina.
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Velasco H, Cid AS, Anjos RM, Zamboni CB, Rizzotto M, Valladares DL, Juri Ayub J. Variability of 137Cs and 40K soil-to-fruit transfer factor in tropical lemon trees during the fruit development period. J Environ Radioact 2012; 104:64-70. [PMID: 22115437 DOI: 10.1016/j.jenvrad.2011.09.016] [Citation(s) in RCA: 5] [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] [Received: 11/11/2010] [Revised: 09/17/2011] [Accepted: 09/30/2011] [Indexed: 05/31/2023]
Abstract
In this investigation we evaluate the soil uptake of (137)Cs and (40)K by tropical plants and their consequent translocation to fruits, by calculating the soil-to-fruit transfer factors defined as F(v) = [concentration of radionuclide in fruit (Bq kg(-1) dry mass)/concentration of radionuclide in soil (Bq kg(-1) dry mass in upper 20 cm)]. In order to obtain F(v) values, the accumulation of these radionuclides in fruits of lemon trees (Citrus limon B.) during the fruit growth was measured. A mathematical model was calibrated from the experimental data allowing simulating the incorporation process of these radionuclides by fruits. Although the fruit incorporates a lot more potassium than cesium, both radionuclides present similar absorption patterns during the entire growth period. F(v) ranged from 0.54 to 1.02 for (40)K and from 0.02 to 0.06 for (137)Cs. Maximum F(v) values are reached at the initial time of fruit growth and decrease as the fruit develops, being lowest at the maturation period. As a result of applying the model a decreasing exponential function is derived for F(v) as time increases. The agreement between the theoretical approach and the experimental values is satisfactory.
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Affiliation(s)
- H Velasco
- GEA - Instituto de Matemática Aplicada San Luis (IMASL), Universidad Nacional de San Luis, CCT-San Luis CONICET, Ej. de los Andes 950, D5700HHW San Luis, Argentina.
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Estellita L, Santos A, Anjos R, Yoshimura E, Velasco H, da Silva A, Aguiar J. Analysis and risk estimates to workers of Brazilian granitic industries and sandblasters exposed to respirable crystalline silica and natural radionuclides. RADIAT MEAS 2010. [DOI: 10.1016/j.radmeas.2010.02.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Anjos RM, Umisedo N, da Silva AAR, Estellita L, Rizzotto M, Yoshimura EM, Velasco H, Santos AMA. Occupational exposure to radon and natural gamma radiation in the La Carolina, a former gold mine in San Luis Province, Argentina. J Environ Radioact 2010; 101:153-158. [PMID: 19945773 DOI: 10.1016/j.jenvrad.2009.09.010] [Citation(s) in RCA: 6] [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] [Received: 05/25/2009] [Revised: 09/18/2009] [Accepted: 09/20/2009] [Indexed: 05/28/2023]
Abstract
Radon and gamma radiation level measurements were carried out inside the La Carolina mine, one of the oldest gold mining camps of southern South America, which is open for touristic visits nowadays. CR-39 track-etch detectors and thermoluminescent dosimeters of natural CaF(2) and LiF TLD-100 were exposed at 14 points along the mine tunnels in order to estimate the mean (222)Rn concentration and the ambient dose equivalent during the summer season (November 2008 to February 2009). The values for the (222)Rn concentration at each monitoring site ranged from 1.8+/-0.1 kBqm(-3) to 6.0+/-0.5 kBqm(-3), with a mean value of 4.8 kBqm(-3), indicating that these measurements exceed in about three times the upper action level recommended by ICRP for workplaces. The correlations between radon and gamma radiation levels inside the mine were also investigated. Effective doses due to (222)Rn and gamma rays inside the mine were determined, resulting in negligible values to tourists. Considering the effective dose to the mine tourist guides, values exceeding 20mSv of internal contribution to the effective doses can be reached, depending on the number of working hours inside the mine.
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Affiliation(s)
- R M Anjos
- Instituto de Física, Universidade Federal Fluminense, Av. Gal Milton Tavares de Souza, s/no, Gragoatá, 24210-340, Niterói, RJ, Brazil.
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Juri Ayub J, Di Gregorio DE, Velasco H, Huck H, Rizzotto M, Lohaiza F. Short-term seasonal variability in 7Be wet deposition in a semiarid ecosystem of central Argentina. J Environ Radioact 2009; 100:977-981. [PMID: 19716212 DOI: 10.1016/j.jenvrad.2009.08.001] [Citation(s) in RCA: 7] [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: 10/08/2008] [Revised: 07/08/2009] [Accepted: 08/04/2009] [Indexed: 05/28/2023]
Abstract
The (7)Be wet deposition has been intensively investigated in a semiarid region at San Luis Province, Argentina. From November 2006 to May 2008, the (7)Be content in rainwater was determined in 58 individual rain events, randomly comprising more than 50% of all individual precipitations at the sampling period. (7)Be activity concentration in rainwater ranged from 0.7+/-0.3 Bq l(-1) to 3.2+/-0.7 Bq l(-1), with a mean value of 1.7 Bq l(-1) (sd=0.53 Bq l(-1)). No relationship was found between (7)Be content in rainwater and (a) rainfall amount, (b) precipitation intensity and (c) elapsed time between events. (7)Be ground deposition was found to be well correlated with rainfall amount (R=0.92). For the precipitation events considered, the (7)Be depositional fluxes ranged from 1.1 to 120 Bq m(-2), with a mean value of 32.7 Bq m(-2) (sd=29.9 Bq m(-2)). The annual depositional flux was estimated at 1140+/-120 Bq m(-2)y(-1). Assuming the same monthly deposition pattern and that the (7)Be content in soil decreases only through radioactive decay, the seasonal variation of (7)Be areal activity density in soil was estimated. Results of this investigation may contribute to a valuable characterization of (7)Be input in the explored semiarid ecosystem and its potential use as tracer of environmental processes.
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Affiliation(s)
- J Juri Ayub
- Grupo de Estudios Ambientales, Instituto de Matemática Aplicada San Luis, Universidad Nacional de San Luis - CONICET, Ejercito de los Andes 950, D5700HHW San Luis, Argentina
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Velasco H, Ayub JJ, Sansone U. Influence of crop types and soil properties on radionuclide soil-to-plant transfer factors in tropical and subtropical environments. J Environ Radioact 2009; 100:733-738. [PMID: 19178988 DOI: 10.1016/j.jenvrad.2008.12.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2008] [Revised: 11/21/2008] [Accepted: 12/17/2008] [Indexed: 05/27/2023]
Abstract
This paper presents a descriptive statistical analysis of radionuclide soil-to-plant transfer factors (Fv) for tropical and subtropical environments. These values were collected from previous databases and standard publications with the objective of contributing to the IAEA Technical Report Series: Handbook of parameter values for the prediction of radionuclide transfer to humans in terrestrial and freshwater environments. More than 2200 Fv values of different radionuclides were gathered and arranged into specific databases, detailing relevant information regarding the environments where this parameter was calculated. This study explores the dependence of Fv values to crop types, and soil properties. The wide variability and uncertainty observed in calculated Fv values were considerably reduced when the data was independently grouped into clusters containing the same radionuclide/plant group/soil type combinations. For each cluster the principal statistical quantities were determined. Using these quantities, the Fv distributions of each data set was explored. Fv probability distribution is discussed to clarify the use of this empirical parameter in radioecological and radiological assessment models.
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Affiliation(s)
- H Velasco
- GEA, Instituto de Matemática Aplicada San Luis (IMASL), Universidad Nacional de San Luis, Consejo Nacional de Investigaciones Científicas y Técnicas, San Luis, Argentina.
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Vandenhove H, Olyslaegers G, Sanzharova N, Shubina O, Reed E, Shang Z, Velasco H. Proposal for new best estimates of the soil-to-plant transfer factor of U, Th, Ra, Pb and Po. J Environ Radioact 2009; 100:721-32. [PMID: 19058886 DOI: 10.1016/j.jenvrad.2008.10.014] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2007] [Revised: 10/10/2008] [Accepted: 10/20/2008] [Indexed: 05/06/2023]
Abstract
There is increasing interest in radiological assessment of discharges of naturally occurring radionuclides into the terrestrial environment. Such assessments require parameter values for the pathways considered in predictive models. An important pathway for human exposure is via ingestion of food crops and animal products. One of the key parameters in environmental assessment is therefore the soil-to-plant transfer factor to food and fodder crops. The objective of this study was to compile data, based on an extensive literature survey, concerning soil-to-plant transfer factors for uranium, thorium, radium, lead, and polonium. Transfer factor estimates were presented for major crop groups (Cereals, Leafy vegetables, Non-leafy vegetables, Root crops, Tubers, Fruits, Herbs, Pastures/grasses, Fodder), and also for some compartments within crop groups. Transfer factors were also calculated per soil group, as defined by their texture and organic matter content (Sand, Loam, Clay and Organic), and evaluation of transfer factors' dependency on specific soil characteristics was performed following regression analysis. The derived estimates were compared with estimates currently in use.
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Affiliation(s)
- H Vandenhove
- Belgian Nuclear Research Centre, Biosphere Impact Studies, Mol, Belgium.
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Rizzotto M, Toso J, Velasco H, Belli M, Sansone U. Temporal reduction of the external gamma dose rate due to 137Cs mobility in sandy beaches. J Radioanal Nucl Chem 2009. [DOI: 10.1007/s10967-009-7456-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Velasco H, Juri Ayub J, Sansone U. Analysis of radionuclide transfer factors from soil to plant in tropical and subtropical environments. Appl Radiat Isot 2008; 66:1759-63. [PMID: 18539037 DOI: 10.1016/j.apradiso.2007.06.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2007] [Accepted: 06/03/2007] [Indexed: 10/22/2022]
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Velasco H, Rizzotto M, Merkis N, Belli M, Sansone U. Contribution to the external gamma dose rate from 137Cs and 40K activity concentrations determined in the vertical profile of sandy beaches. J Radioanal Nucl Chem 2007. [DOI: 10.1007/s10967-007-6846-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Bernal JL, del Nozal MJ, Velasco H, Toribio L. HPLC Versus SFC for the Determination of Salbutamol Sulphate and Its Impurities in Pharmaceuticals. J LIQ CHROMATOGR R T 2006. [DOI: 10.1080/10826079608005493] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- J. L. Bernal
- a Department of Analytical Chemistry Faculty of Sciences , University of Valladolid , E-47005, Valladolid, Spain
| | - M. J. del Nozal
- a Department of Analytical Chemistry Faculty of Sciences , University of Valladolid , E-47005, Valladolid, Spain
| | - H. Velasco
- a Department of Analytical Chemistry Faculty of Sciences , University of Valladolid , E-47005, Valladolid, Spain
| | - L. Toribio
- a Department of Analytical Chemistry Faculty of Sciences , University of Valladolid , E-47005, Valladolid, Spain
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Velasco H, Carreño E, Rodríguez M, Belle M, Sansone U. Radioecological software package: an interactive computational system to simulate the behaviour of radionuclides in semi-natural environments. J Environ Radioact 2004; 73:223-230. [PMID: 15119326 DOI: 10.1016/j.jenvrad.2003.08.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
RSP (Radioecological Software Package) is an interactive support system that simulates the behaviour of radionuclides in semi-natural environments and the consequences on the population in terms of the external exposure. RSP consists of three modules: the first one, soil mobility, simulates the vertical transport of radionuclide in soil using the mathematical model RABES. The second module, soil -to-plant transfer, simulates the radionuclide soil-to-plant transfer factor reported in the literature. Soil properties, vegetation types and environmental conditions are taken into consideration in the simulation process. In the third module, dose assessment, the dose-rate factor in air at a height of 1 m above ground can be calculated for sources distributed in a slab of finite thickness dn sources which are exponentially distributed with depth. The calculations are performed using DAGES Model, a Monte Carlo algorithm developed to simulated the photon transport for the soil/air configuration. A free copy of RSP can be downloaded from the website: http://imasl-apat.unsl.edu.ar.
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Affiliation(s)
- H Velasco
- Instituto de Matemática Aplicada San Luis, Universidad Nacional de San Luis, Consejo Nacional de investigaciones Científicas y Técnicas, Ej. de los Andes, San Luis, Argentina.
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