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2.
Mar Drugs ; 21(6)2023 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-37367681

RESUMO

α-Conotoxins are well-known probes for the characterization of the various subtypes of nicotinic acetylcholine receptors (nAChRs). Identifying new α-conotoxins with different pharmacological profiles can provide further insights into the physiological or pathological roles of the numerous nAChR isoforms found at the neuromuscular junction, the central and peripheral nervous systems, and other cells such as immune cells. This study focuses on the synthesis and characterization of two novel α-conotoxins obtained from two species endemic to the Marquesas Islands, namely Conus gauguini and Conus adamsonii. Both species prey on fish, and their venom is considered a rich source of bioactive peptides that can target a wide range of pharmacological receptors in vertebrates. Here, we demonstrate the versatile use of a one-pot disulfide bond synthesis to achieve the α-conotoxin fold [Cys 1-3; 2-4] for GaIA and AdIA, using the 2-nitrobenzyl (NBzl) protecting group of cysteines for effective regioselective oxidation. The potency and selectivity of GaIA and AdIA against rat nicotinic acetylcholine receptors were investigated electrophysiologically and revealed potent inhibitory activities. GaIA was most active at the muscle nAChR (IC50 = 38 nM), whereas AdIA was most potent at the neuronal α6/3 ß2ß3 subtype (IC50 = 177 nM). Overall, this study contributes to a better understanding of the structure-activity relationships of α-conotoxins, which may help in the design of more selective tools.


Assuntos
Conotoxinas , Caramujo Conus , Receptores Nicotínicos , Animais , Ratos , Conotoxinas/farmacologia , Conotoxinas/química , Caramujo Conus/química , Caramujo Conus/fisiologia , Antagonistas Nicotínicos/farmacologia , Caramujos , Polinésia
3.
Emerg Infect Dis ; 29(7): 1490-1492, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37347937

RESUMO

We definitively characterized Mycobacterium angelicum, an aquatic zoonotic opportunistic pathogen of the M. szulgai complex, using a polyphasic approach that included whole-genome sequencing. The sequence was obtained on the island of Tahiti, French Polynesia, from a urine specimen collected from a patient experiencing a urinary tract infection.


Assuntos
Infecções por Mycobacterium não Tuberculosas , Mycobacterium , Sistema Urinário , Humanos , Mycobacterium/genética , Infecções por Mycobacterium não Tuberculosas/diagnóstico , Infecções por Mycobacterium não Tuberculosas/microbiologia , Polinésia/epidemiologia
4.
JAMA Netw Open ; 6(5): e2311908, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-37145599

RESUMO

Importance: Due to the amount of iodine 131 released in nuclear tests and its active uptake by the thyroid, differentiated thyroid carcinoma (DTC) is the most serious health risk for the population living near sites of nuclear tests. Whether low doses to the thyroid from nuclear fallout are associated with increased risk of thyroid cancer remains a controversial issue in medicine and public health, and a misunderstanding of this issue may be associated with overdiagnosis of DTCs. Design, Setting, and Participants: This case-control study was conducted by extending a case-control study published in 2010 that included DTCs diagnosed between 1984 and 2003 by adding DTCs diagnosed between 2004 and 2016 and improving the dose assessment methodology. Data on 41 atmospheric nuclear tests conducted by France between 1966 and 1974 in French Polynesia (FP) were assessed from original internal radiation-protection reports, which the French military declassified in 2013 and which included measurements in soil, air, water, milk, and food in all FP archipelagos. These original reports led to an upward reassessment of the nuclear fallout from the tests and a doubling of estimates of the mean thyroid radiation dose received by inhabitants from 2 mGy to nearly 5 mGy. Included patients were diagnosed from 1984 to 2016 with DTC at age 55 years or younger and were born in and resided in FP at diagnosis; 395 of 457 eligible cases were included, and up to 2 controls per case nearest by birthdate and matched on sex were identified from the FP birth registry. Data were analyzed from March 2019 through October 2021. Exposure: The radiation dose to the thyroid gland was estimated using recently declassified original radiation-protection service reports, meteorological reports, self-reported lifestyle information, and group interviews of key informants and female individuals who had children at the time of these tests. Main Outcomes and Measures: The lifetime risk of DTC based on Biological Effects of Ionizing Radiation (BEIR) VII models was estimated. Results: A total of 395 DTC cases (336 females [85.1%]; mean [SD] age at end of follow-up, 43.6 [12.9] years) and 555 controls (473 females [85.2%]; mean [SD] age at end of follow-up, 42.3 [12.5] years) were included. No association was found between thyroid radiation dose received before age 15 years and risk of DTC (excess relative risk [ERR] per milligray, 0.04; 95% CI, -0.09 to 0.17; P = .27). When excluding unifocal noninvasive microcarcinomas, the dose response was significant (ERR per milligray, 0.09; 95% CI, -0.03 to 0.02; P = .02), but several incoherencies with the results of the initial study reduce the credibility of this result. The lifetime risk for the entire FP population was 29 cases of DTC (95% CI, 8-97 cases), or 2.3% (95% CI, 0.6%-7.7%) of 1524 sporadic DTC cases in this population. Conclusions and Relevance: This case-control study found that French nuclear tests were associated with an increase in lifetime risk of PTC in FP residents of 29 cases of PTC. This finding suggests that the number of thyroid cancer cases and the true order of magnitude of health outcomes associated with these nuclear tests were small, which may reassure populations of this Pacific territory.


Assuntos
Adenocarcinoma , Cinza Radioativa , Neoplasias da Glândula Tireoide , Criança , Humanos , Feminino , Pessoa de Meia-Idade , Adolescente , Cinza Radioativa/efeitos adversos , Estudos de Casos e Controles , Neoplasias da Glândula Tireoide/epidemiologia , Neoplasias da Glândula Tireoide/etiologia , Risco , Adenocarcinoma/complicações , Polinésia/epidemiologia
5.
Mar Drugs ; 20(6)2022 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-35736151

RESUMO

Gambierdiscus and Fukuyoa dinoflagellates produce a suite of secondary metabolites, including ciguatoxins (CTXs), which bioaccumulate and are further biotransformed in fish and marine invertebrates, causing ciguatera poisoning when consumed by humans. This study is the first to compare the performance of the fluorescent receptor binding assay (fRBA), neuroblastoma cell-based assay (CBA-N2a), and liquid chromatography tandem mass spectrometry (LC-MS/MS) for the quantitative estimation of CTX contents in 30 samples, obtained from four French Polynesian strains of Gambierdiscus polynesiensis. fRBA was applied to Gambierdiscus matrix for the first time, and several parameters of the fRBA protocol were refined. Following liquid/liquid partitioning to separate CTXs from other algal compounds, the variability of CTX contents was estimated using these three methods in three independent experiments. All three assays were significantly correlated with each other, with the highest correlation coefficient (r2 = 0.841) found between fRBA and LC-MS/MS. The CBA-N2a was more sensitive than LC-MS/MS and fRBA, with all assays showing good repeatability. The combined use of fRBA and/or CBA-N2a for screening purposes and LC-MS/MS for confirmation purposes allows for efficient CTX evaluation in Gambierdiscus. These findings, which support future collaborative studies for the inter-laboratory validation of CTX detection methods, will help improve ciguatera risk assessment and management.


Assuntos
Ciguatera , Ciguatoxinas , Dinoflagellida , Animais , Cromatografia Líquida , Ciguatera/etiologia , Ciguatoxinas/análise , Dinoflagellida/química , Polinésia , Espectrometria de Massas em Tandem
6.
Mar Drugs ; 20(4)2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35447924

RESUMO

Ciguatera poisoning (CP) results from the consumption of coral reef fish or marine invertebrates contaminated with potent marine polyether compounds, namely ciguatoxins. In French Polynesia, 220 fish specimens belonging to parrotfish (Chlorurus microrhinos, Scarus forsteni, and Scarus ghobban), surgeonfish (Naso lituratus), and groupers (Epinephelus polyphekadion) were collected from two sites with contrasted risk of CP, i.e., Kaukura Atoll versus Mangareva Island. Fish age and growth were assessed from otoliths' yearly increments and their ciguatoxic status (negative, suspect, or positive) was evaluated by neuroblastoma cell-based assay. Using permutational multivariate analyses of variance, no significant differences in size and weight were found between negative and suspect specimens while positive specimens showed significantly greater size and weight particularly for E. polyphekadion and S. ghobban. However, eating small or low-weight specimens remains risky due to the high variability in size and weight of positive fish. Overall, no relationship could be evidenced between fish ciguatoxicity and age and growth characteristics. In conclusion, size, weight, age, and growth are not reliable determinants of fish ciguatoxicity which appears to be rather species and/or site-specific, although larger fish pose an increased risk of poisoning. Such findings have important implications in current CP risk management programs.


Assuntos
Bass , Ciguatera , Ciguatoxinas , Animais , Ciguatoxinas/análise , Ciguatoxinas/toxicidade , Recifes de Corais , Peixes , Polinésia , Alimentos Marinhos/análise
7.
Sci Rep ; 11(1): 23546, 2021 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-34876599

RESUMO

Mass thermal bleaching events are a primary threat to coral reefs, yet the sublethal impacts, particularly on energetics and reproduction, are poorly characterized. Given that the persistence of coral populations is contingent upon the reproduction of individuals that survive disturbances, there is an urgent need to understand the sublethal effects of bleaching on reproductive output to accurately predict coral recovery rates. In 2019, the French Polynesian island of Mo'orea experienced a severe mass bleaching event accompanied by widespread coral mortality. At the most heavily impacted sites, we observed Acropora hyacinthus individuals that were resistant to bleaching, alongside colonies that bleached but showed signs of symbiont recovery shortly after the bleaching event. We collected fragments from A. hyacinthus colonies five months post-bleaching and, using energetic assays and histological measurements, examined the physiological and reproductive consequences of these two distinct heat stress responses. Despite healthy appearances in both resistant and recovered corals, we found that recovered colonies had significantly reduced energy reserves compared to resistant colonies. In addition, we detected compound effects of stress on reproduction: recovered colonies displayed both a lower probability of containing gametes and lower fecundity per polyp. Our results indicate that bleaching inflicts an energetic constraint on the concurrent re-accumulation of energy reserves and development of reproductive material, with decreased reproductive potential of survivors possibly hampering overall reef resilience. These findings highlight the presence of intraspecific responses to bleaching and the importance of considering multiple trajectories for individual species when predicting population recovery following disturbance.


Assuntos
Antozoários/fisiologia , Branqueamento de Corais/efeitos adversos , Animais , Recifes de Corais , Metabolismo Energético/fisiologia , Feminino , Resposta ao Choque Térmico/fisiologia , Masculino , Polinésia , Reprodução/fisiologia , Simbiose/fisiologia
8.
Bull Cancer ; 108(12): 1077-1084, 2021 Dec.
Artigo em Francês | MEDLINE | ID: mdl-34802717

RESUMO

INTRODUCTION: Overseas France represents 18 % of French territory and is home to 4 % of its population for whom there is unequal treatment in the field of rare/complex cancer. AIM: To report our experience of intercontinental multidisciplinary videoconferencing between the French mainland and Pacific territories. METHODS: Every other friday, three centers located in Papeete, Nouméa and Paris-Villejuif connected between 6:30 AM and 8:00 AM GMT to discuss cases of rare/complex cancers. RESULTS: Between November 2019 and December 2020, 323 presentations implicating 233 patients involved sarcoma (n=93), digestive pathology (n=60), neuroendocrine tumors (n=35), urology (n=24), gynecology (n=24), neurology (n=16), thyroid pathology (n=14), dermatology (n=14), senology (n=11), hematology (n=11), ENT pathology (n=10), pathology thoracic (n=10) and pediatrics (n=1). Of the 233 patients, 134 (57.5 %) living in New Caledonia and 99 (42.5 %) in French Polynesia, 117 (50.5 %) had metastatic disease. 39 patients (16.7 %) were transferred to French mainland (EVASAN), for surgery (n=25), vectorized radiotherapy (n=7), biopsy (n=5), chemotherapy (n=1) or inclusion in a clinical trial (n=1). 195 patients (83.7 %) were treated at home, 15 (6.4 %) are still awaiting a decision and 4 (1.7 %) lost to follow-up. CONCLUSION: The use of videoconferencing to discuss rare/complex cancer cases was effective in guaranteeing French overseas population access to innovative therapies and clinical trials, limiting the need for intercontinental transfer to 16.7 %.


Assuntos
Neoplasias/epidemiologia , Doenças Raras/epidemiologia , Comunicação por Videoconferência/organização & administração , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Feminino , França/epidemiologia , Acessibilidade aos Serviços de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/terapia , Nova Caledônia/epidemiologia , Polinésia/epidemiologia , Doenças Raras/terapia , Transporte de Pacientes/estatística & dados numéricos , Adulto Jovem
9.
Mar Drugs ; 19(11)2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34822515

RESUMO

Ciguatera poisoning (CP) cases linked to the consumption of deep-water fish occurred in 2003 in the Gambier Islands (French Polynesia). In 2004, on the request of two local fishermen, the presence of ciguatoxins (CTXs) was examined in part of their fish catches, i.e., 22 specimens representing five deep-water fish species. Using the radioactive receptor binding assay (rRBA) and mouse bioassay (MBA), significant CTX levels were detected in seven deep-water specimens in Lutjanidae, Serranidae, and Bramidae families. Following additional purification steps on the remaining liposoluble fractions for 13 of these samples (kept at -20 °C), these latter were reanalyzed in 2018 with improved protocols of the neuroblastoma cell-based assay (CBA-N2a) and liquid chromatography tandem mass spectrometry (LC-MS/MS). Using the CBA-N2a, the highest CTX-like content found in a specimen of Eumegistus illustris (Bramidae) was 2.94 ± 0.27 µg CTX1B eq. kg-1. Its toxin profile consisted of 52-epi-54-deoxyCTX1B, CTX1B, and 54-deoxyCTX1B, as assessed by LC-MS/MS. This is the first study demonstrating that deep-water fish are potential ciguatera vectors and highlighting the importance of a systematic monitoring of CTXs in all exploited fish species, especially in ciguatera hotspots, including deep-water fish, which constitute a significant portion of the commercial deep-sea fisheries in many Asian-Pacific countries.


Assuntos
Aquicultura , Ciguatera/prevenção & controle , Peixes , Animais , Organismos Aquáticos , Humanos , Camundongos , Polinésia
10.
PLoS One ; 16(9): e0256877, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34473769

RESUMO

In French Polynesia, the first case of SARS-CoV-2 infection was detected on March 10th, 2020, in a resident returning from France. Between March 28th and July 14th, international air traffic was interrupted and local transmission of SARS-CoV-2 was brought under control, with only 62 cases recorded. The main challenge for reopening the air border without requiring travelers to quarantine on arrival was to limit the risk of re-introducing SARS-CoV-2. Specific measures were implemented, including the obligation for all travelers to have a negative RT-PCR test for SARS-CoV-2 carried out within 3 days before departure, and to perform another RT-PCR testing 4 days after arrival. Because of limitation in available medical staff, travelers were provided a kit allowing self-collection of oral and nasal swabs. In addition to increase our testing capacity, self-collected samples from up to 10 travelers were pooled before RNA extraction and RT-PCR testing. When a pool tested positive, RNA extraction and RT-PCR were performed on each individual sample. We report here the results of COVID-19 surveillance (COV-CHECK PORINETIA) conducted between July 15th, 2020, and February 15th, 2021, in travelers using self-collection and pooling approaches. We tested 5,982 pools comprising 59,490 individual samples, and detected 273 (0.46%) travelers positive for SARS-CoV-2. A mean difference of 1.17 Ct (CI 95% 0.93-1.41) was found between positive individual samples and pools (N = 50), probably related to the volume of samples used for RNA extraction (200 µL versus 50 µL, respectively). Retrospective testing of positive samples self-collected from October 20th, 2020, using variants-specific amplification kit and spike gene sequencing, found at least 6 residents infected by the Alpha variant. Self-collection and pooling approaches allowed large-scale screening for SARS-CoV-2 using less human, material and financial resources. Moreover, this strategy allowed detecting the introduction of SARS-CoV-2 variants of concern in French Polynesia.


Assuntos
Teste para COVID-19/métodos , COVID-19/diagnóstico , Programas de Rastreamento/métodos , Vigilância da População/métodos , Manejo de Espécimes/métodos , Viagem , COVID-19/epidemiologia , COVID-19/virologia , Teste para COVID-19/instrumentação , Epidemias/prevenção & controle , França/epidemiologia , Humanos , Polinésia/epidemiologia , Estudos Prospectivos , RNA Viral/genética , RNA Viral/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , SARS-CoV-2/genética , SARS-CoV-2/fisiologia , Manejo de Espécimes/instrumentação
11.
Toxins (Basel) ; 13(9)2021 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-34564650

RESUMO

Ciguatera poisoning is a globally occurring seafood disease caused by the ingestion of marine products contaminated with dinoflagellate produced neurotoxins. Persistent forms of ciguatera, which prove to be highly debilitating, are poorly studied and represent a significant medical issue. The present study aims to better understand chronic ciguatera manifestations and identify potential predictive factors for their duration. Medical files of 49 patients were analyzed, and the post-hospitalization evolution of the disease assessed through a follow-up questionnaire. A rigorous logistic lasso regression model was applied to select significant predictors from a list of 37 patient characteristics potentially predictive of having chronic symptoms. Missing data were handled by complete case analysis, and a survival analysis was implemented. All models used standardized variables, and multiple comparisons in the survival analyses were handled by Bonferroni correction. Among all studied variables, five significant predictors of having symptoms lasting ≥3 months were identified: age, tobacco consumption, acute bradycardia, laboratory measures of urea, and neutrophils. This exploratory, hypothesis-generating study contributes to the development of ciguatera epidemiology by narrowing the list from 37 possible predictors to a list of five predictors that seem worth further investigation as candidate risk factors in more targeted studies of ciguatera symptom duration.


Assuntos
Ciguatera/epidemiologia , Hospitalização/estatística & dados numéricos , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Polinésia/epidemiologia , Prevalência
12.
J Environ Radioact ; 235-236: 106624, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34059369

RESUMO

The inventories of 137Cs (503 ±â€¯34 Bq.m-2), 241Am (11.3 ±â€¯1.2 Bq.m-2), 241Pu (33.7 ±â€¯3.4 Bq.m-2), 238Pu (6.82 ±â€¯0.87 Bq.m-2) and 239+240Pu (113.0 ±â€¯5.9 Bq.m-2), sum of 239Pu (100 ±â€¯11 Bq.m-2) and 240Pu (14.5 ±â€¯1.7 Bq.m-2), in the Gambier archipelago (23°S) of the French Polynesia, are well higher the global fallout at this latitude, in unequal proportions for the different radionuclides. (240Pu/239Pu)AR (AR: atomic ratio) of 0.0394 ±â€¯0.0062, and (241Pu/239Pu)AR of (2.03 ±â€¯0.39)10-4, confirm that the overwhelmingly dominant source of these radionuclides comes from local fallout during the 1970s of the French atmospheric tests of Moruroa and Fangataufa located nearly 400 km from Gambier. The signatures of the local fallout were deduced from the excess of its inventory in 137Cs and from the mixing lines established from the signatures of the global fallout, some of the test sites and the isotopic ratios measured in Gambier. Signatures obtained are 2.0 ±â€¯0.4 for 137Cs/239+240Pu, 0.045 ±â€¯0.008 for 238Pu/239+240Pu, 0.031 ±â€¯0.009 for 241Am/239+240Pu, 0.092 ±â€¯0.027 for 241Pu/239+240Pu, 0.0163 ±â€¯0.0049 for (240Pu/239Pu)AR, (0.78 ±â€¯0.23)10-4 for (241Pu/239Pu)AR. The concordance of the mixing lines of the [(240Pu/239Pu)AR, (241Pu/239Pu)AR] and the linear regression of these ratios measured in the stratosphere (40°S) during the 1970s, indicates that the signatures of the close-in deposition are also those of the stratospheric injections of the French tests. The signatures of stratospheric fallout in the Southern Hemisphere were evaluated by considering that the fission energy of these injections represents 11% and that of the Northern Hemisphere represents 89% and that the isotopic ratios of stratospheric injections remained the same over the period 1970-1974. The activity ratios deducted are 21.9 ±â€¯0.1 in 137Cs/239+240Pu, 0.11 ±â€¯0.05 in 238Pu/239+240Pu, 1.03 ±â€¯0.12 in 241Pu/239+240Pu and 0.35 ±â€¯0.04 in 241Am/239+240Pu. The associated atom ratios are 0.157 ±â€¯0.011 for (240Pu/239Pu)AR and (8.33 ±â€¯0.48)10-4 for (241Pu/239Pu)AR. These signatures appear to be consistent with the results of the inventories at Hiva Oa, located more than 1,000 km north of both French test sites, and with those found in the Australian continent, in regions not impacted by UK-test debris. The proportions of close-in tropospheric fallout from the French tests are about 90% in Gambier. They represent a proportion in the inventories of 40% for the 137Cs, 60% for 241Am and in the range between 80 and 90% for Pu isotopes.


Assuntos
Plutônio , Monitoramento de Radiação , Cinza Radioativa , Austrália , Radioisótopos de Césio , Ilhas , Plutônio/análise , Polinésia , Cinza Radioativa/análise
13.
ANZ J Surg ; 91(5): 795-801, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33870624

RESUMO

BACKGROUND: Papua New Guinea, Pacific Island nations, and Timor-Leste represent a range of island nations with populations ranging from a few thousand to 8 million. They perform on average about 25% of the Lancet Commission of Global Surgery's target 5000 per 100 000 population and their health workforce have significant deficits of trained surgeons and anaesthetists. This study was conducted to determine how the current national health plans of these nations have included surgery and anaesthesia. METHODS: The most recent (as of December 2018) published national health plans of 10 Pacific Island nations (Cook Islands, Fiji, Nauru, Federated States of Micronesia, Kiribati, Samoa, Solomon Islands, Tonga, Tuvalu and Vanuatu), Papua New Guinea and Timor-Leste were reviewed for content and process, searching for key words and identifying themes related to surgery and anaesthesia. RESULTS: There were 12 national health plans with a combined total of 478 pages. There was limited surgical and/or anaesthesia input within the planning process. Injuries, blindness, cancer and non-communicable diseases were included themes, but the potential role of surgical care in addressing these conditions was not well documented. The need for better information and registries was noted by several nations but possible surgical care delivery or outcome metrics were not included. CONCLUSION: There is limited mention of surgical and anaesthesia care planning within current health plans in the Pacific, PNG and TL. There is a need for greater surgical and anaesthesia engagement in future plans with performance measured against World Health Organization core surgical indicators.


Assuntos
Procedimentos Cirúrgicos Operatórios , Anestesia , Fiji , Humanos , Ilhas do Pacífico , Papua Nova Guiné , Polinésia , Timor-Leste/epidemiologia
14.
Asian Pac J Cancer Prev ; 22(3): 801-809, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33773544

RESUMO

OBJECTIVE: To evaluate the potential radiological impact of atmospheric nuclear weapons tests conducted in 1966-1974 at Mururoa and Fangataufa atolls on populations in Oceania, South America and Africa. METHODS: Results of measurements of total beta(ß)-concentrations in filtered air and 131I activity concentrations in locally produced cow's milk in Oceania, South America and Africa after the tests were compared with those in French Polynesia. Radiation doses due to external irradiation and thyroid doses due to 131I intake with milk by local populations were also compared. RESULTS: Higher total ß-concentrations in filtered air, 131I activity concentrations in locally produced milk and radiation doses to local population were, in general, observed in French Polynesia than in other countries in the southern hemisphere. However, for specific years during the testing period, the radiological impact to South America was found to be similar or slightly higher than that to Tahiti. The resulting thyroid doses in the considered countries were lower than those in French Polynesia with two exceptions: thyroid doses due to 131I intake with cow's milk for 1-y old child in 1968 were higher in Peru (0.35 mGy) and in Madagascar (0.30 mGy) than in Tahiti (0.25 mGy). However, the populations outside French Polynesia received doses lower than those from the natural sources of radiation. CONCLUSION: According to the current knowledge in radiation epidemiology, it is very unlikely that nuclear fallout due to French nuclear tests had a measurable radiological and health impact outside French Polynesia.
.


Assuntos
Armas Nucleares , Doses de Radiação , Exposição à Radiação/estatística & dados numéricos , África , Animais , Partículas beta , França , Humanos , Radioisótopos do Iodo/análise , Madagáscar , Leite/química , Oceania , Peru , Polinésia , Monitoramento de Radiação , América do Sul
16.
Health Phys ; 120(1): 34-55, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33002966

RESUMO

Thyroid doses were estimated for the subjects of a population-based case-control study of thyroid cancer in a population exposed to fallout after atmospheric nuclear weapons tests conducted in French Polynesia between 1966 and 1974. Thyroid doses due to (1) intake of I and of short-lived radioiodine isotopes (I, I, I) and Te, (2) external irradiation from gamma-emitting radionuclides deposited on the ground, and (3) ingestion of long-lived Cs with foodstuffs were reconstructed for each study subject. The dosimetry model that had been used in 2008 in Phase I of the study was substantially improved with (1) results of radiation monitoring of the environment and foodstuffs, which became available in 2013 for public access, and (2) historical data on population lifestyle related to the period of the tests, which were collected in 2016-2017 using focus-group discussions and key informant interviews. The mean thyroid dose among the study subjects was found to be around 5 mGy while the highest dose was estimated to be around 36 mGy. Doses from I intake ranged up to 27 mGy, while those from intake of short-lived iodine isotopes (I, I, I) and Te ranged up to 14 mGy. Thyroid doses from external exposure ranged up to 6 mGy, and those from internal exposure due to Cs ingestion did not exceed 1 mGy. Intake of I was found to be the main pathway for thyroid exposure accounting for 72% of the total dose. Results of this study are being used to evaluate the risk of thyroid cancer among the subjects of the epidemiologic study of thyroid cancer among French Polynesians.


Assuntos
Radioisótopos do Iodo/efeitos adversos , Radioisótopos do Iodo/análise , Armas Nucleares , Cinza Radioativa/efeitos adversos , Cinza Radioativa/análise , Glândula Tireoide/efeitos da radiação , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Ingestão de Alimentos , Feminino , Feto/efeitos da radiação , Contaminação Radioativa de Alimentos/análise , História do Século XX , Humanos , Lactente , Recém-Nascido , Inalação , Radioisótopos do Iodo/administração & dosagem , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Neoplasias Induzidas por Radiação/epidemiologia , Armas Nucleares/história , Polinésia/epidemiologia , Gravidez , Efeitos Tardios da Exposição Pré-Natal , Doses de Radiação , Exposição à Radiação/efeitos adversos , Exposição à Radiação/análise , Exposição à Radiação/história , Cinza Radioativa/história , Neoplasias da Glândula Tireoide/epidemiologia , Neoplasias da Glândula Tireoide/etiologia , Contaminação Radioativa da Água/efeitos adversos , Contaminação Radioativa da Água/análise
17.
Harmful Algae ; 98: 101888, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-33129466

RESUMO

Among dinoflagellates responsible for benthic harmful algal blooms, the genus Ostreopsis primarily described from tropical areas has been increasingly reported from subtropical and temperate areas worldwide. Several species of this toxigenic genus produce analogs of palytoxin, thus representing a major threat to human and environmental health. The taxonomy of several species needs to be clarified as it was based mostly on morphological descriptions leading in some cases to ambiguous interpretations and misidentifications. The present study aims at reporting a benthic bloom that occurred in April 2019 in Tahiti island, French Polynesia. A complete taxonomic investigation of the blooming Ostreopsis species was realized using light, epifluorescence and field emission electron microscopy and phylogenetic analyses inferred from LSU rDNA and ITS-5.8S rDNA regions. Toxicity of a natural sample and strains isolated from the bloom was assessed using both neuroblastoma cell-based assay and LC-MS/MS analyses. Morphological observations showed that cells were round to oval, large, 58.0-82.5 µm deep (dorso-ventral length) and 45.7-61.2 µm wide. The cingulum was conspicuously undulated, forming a 'V' in ventral view. Thecal plates possessed large pores in depressions, with a collar rim. Detailed observation also revealed the presence of small thecal pores invisible in LM. Phylogenetic analyses were congruent and all sequences clustered within the genotype Ostreopsis sp. 6, in a subclade closely related to sequences from the Gulf of Thailand and Malaysia. No toxicity was found on the field sample but all the strains isolated from the bloom were found to be cytotoxic and produced ostreocin D, a lower amount of ostreocins A and B and putatively other compounds. Phylogenetic data demonstrate the presence of this species in the Gulf of Thailand, at the type locality of O. siamensis, and morphological data are congruent with the original description and support this identification.


Assuntos
Dinoflagellida , Espectrometria de Massas em Tandem , Cromatografia Líquida , Dinoflagellida/genética , Ilhas , Malásia , Oceano Pacífico , Filogenia , Polinésia
18.
Artigo em Inglês | MEDLINE | ID: mdl-33050181

RESUMO

Tobacco use among adolescents is a global problem of public health importance. This study examined the profile of differences and similarities in adolescent tobacco use, and the role of parental monitoring activities among adolescents in three island nations of varying economic status: Cook Islands, Curaçao, and East Timor. Using nationally representative data we conducted regression modeling to determine the effect of four types of parental monitoring activities on tobacco use. Within a recall period of 30 days prior to being surveyed, 29.7% of students in East Timor, 21.6% in Cook Islands, and 13.1% in Curaçao reported having smoked cigarettes and/or used tobacco in other forms during 1 or more days during the preceding 30 days. Lower rates of parental monitoring as measured by four variables (parental understanding of problems and worries; knowing about how free time was being spent; going over things without approval; and checking to see if homework was done) were associated with higher percentages of adolescent tobacco use. Taken together the results underscore the need for increased parental involvement in programs which are designed to reduce tobacco use among adolescents.


Assuntos
Modelos Estatísticos , Relações Pais-Filho , Fumar , Uso de Tabaco , Adolescente , Curaçao/epidemiologia , Feminino , Humanos , Masculino , Poder Familiar , Polinésia/epidemiologia , Análise de Regressão , Fumar/epidemiologia , Inquéritos e Questionários , Timor-Leste/epidemiologia , Uso de Tabaco/epidemiologia
20.
Toxins (Basel) ; 12(5)2020 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-32413988

RESUMO

Ciguatera poisoning is a foodborne illness caused by the consumption of seafood contaminated with ciguatoxins (CTXs) produced by dinoflagellates from the genera Gambierdiscus and Fukuyoa. The suitability of Solid Phase Adsorption Toxin Tracking (SPATT) technology for the monitoring of dissolved CTXs in the marine environment has recently been demonstrated. To refine the use of this passive monitoring tool in ciguateric areas, the effects of deployment time and sampler format on the adsorption of CTXs by HP20 resin were assessed in Anaho Bay (Nuku Hiva Island, French Polynesia), a well-known ciguatera hotspot. Toxicity data assessed by means of the mouse neuroblastoma cell-based assay (CBA-N2a) showed that a 24 h deployment of 2.5 g of resin allowed concentrating quantifiable amounts of CTXs on SPATT samplers. The CTX levels varied with increasing deployment time, resin load, and surface area. In addition to CTXs, okadaic acid (OA) and dinophysistoxin-1 (DTX1) were also detected in SPATT extracts using liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS), consistent with the presence of Gambierdiscus and Prorocentrum species in the environment, as assessed by quantitative polymerase chain reaction (qPCR) and high-throughput sequencing (HTS) metabarcoding analyses conducted on passive window screen (WS) artificial substrate samples. Although these preliminary findings await further confirmation in follow-up studies, they highlight the usefulness of SPATT samplers in the routine surveillance of CP risk on a temporal scale, and the monitoring of other phycotoxin-related risks in ciguatera-prone areas.


Assuntos
Ciguatera/microbiologia , Ciguatoxinas/análise , Dinoflagellida/metabolismo , Monitoramento Ambiental , Água do Mar/parasitologia , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida , Ciguatoxinas/toxicidade , Código de Barras de DNA Taxonômico , Dinoflagellida/genética , Dinoflagellida/crescimento & desenvolvimento , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Camundongos , Oceanos e Mares , Reação em Cadeia da Polimerase , Polinésia , Medição de Risco , Extração em Fase Sólida , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem
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