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1.
Eur J Obstet Gynecol Reprod Biol ; 298: 108-115, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38749071

RESUMO

OBJECTIVES: Hypertensive disorders of pregnancy (HDP) are among the leading causes of maternal morbidity and mortality. The primary objective of this study was to ascertain whether maternal cardiac remodeling is more prevalent in HDP than normotensive pregnancy and if significant change in aortic root size is involved. The secondary objective was to determine the types of cardiac remodeling often associated with HDP. METHODS: A systematic search was conducted across four electronic databases, including Medline, PubMed, Cochrane and EMBASE. The reference lists of selected articles were also searched to ensure no relevant studies were missed. The Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines were followed in this systematic review. RESULTS: Out of 5,278 articles identified by the search terms, 9 were eligible for inclusion in the meta-analysis. The investigation unveiled a greater prevalence of maternal cardiac remodeling in HDP than normotensive pregnancies. The commonest type of maternal cardiac remodeling in both HDP and normotensive pregnancies was eccentric left ventricular hypertrophy, followed by concentric left ventricular remodeling which was more specific to HDP. Notably, left atrial diameter was significantly increased in HDP than normotensive pregnancies, suggesting higher prevalence of diastolic dysfunction. Additionally, the aortic root dimension was significantly increased in HDP than normotensive pregnancies. CONCLUSION: This study underscores the importance of monitoring cardiac health in pregnancy, particularly in those with hypertensive disorders, in order to mitigate potential complications and improve maternal outcomes. Finally, the risk of aortic dissection that may occur as a long-term effect of aortic root enlargement in women with history of HDP ought to be investigated in future studies.


Assuntos
Hipertensão Induzida pela Gravidez , Remodelação Ventricular , Humanos , Feminino , Gravidez , Remodelação Ventricular/fisiologia , Hipertensão Induzida pela Gravidez/fisiopatologia , Hipertensão Induzida pela Gravidez/epidemiologia , Hipertrofia Ventricular Esquerda/fisiopatologia , Hipertrofia Ventricular Esquerda/epidemiologia
2.
Clin Case Rep ; 12(4): e8708, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38566980

RESUMO

Acute aortic dissection in unusual/rare circumstances may become chronic and multi lumen. A high clinical acumen, examination and investigations in the acute setting, may help reduce late/misdiagnosis and complications in low resource settings.

3.
Clin Case Rep ; 12(2): e8494, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38380377

RESUMO

Marfan syndrome (MFS) is an autosomal dominantly inherited condition that has varying phenotypic expressions. This case report describes one such African patient, from Ghana, who had typical clinical and imaging traits of MFS but was first diagnosed incidentally at the age of 23 years. In this report, we explore the challenges of early diagnosis in this population.

4.
J Med Case Rep ; 17(1): 122, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-37016396

RESUMO

BACKGROUND: Immune thrombocytopenic purpura is a condition associated with an unusual, unexplained, and sometimes very severe reduction in the level of platelets in the blood. Though documented, its association with Graves' disease is not very common and can easily be missed or misdiagnosed, leading to excessive bleeding and mortality. Treatment with steroids and antithyroid medications has been shown to be beneficial in correcting thrombocytopenia in these patients, although the response is varied. We report on a patient with Graves' disease who presents with immune thrombocytopenic purpura. CASE PRESENTATION: A 37-year-old Ghanaian female presented to our hospital's emergency department with a complaint of palpitations, difficulty breathing, easy fatigue, and headaches. She had been referred from a peripheral hospital as a case of thrombocytopenia, severe anemia, and anterior neck swelling. She was diagnosed with Graves' disease 2 years ago, became euthyroid during treatment, but defaulted. On further examination and investigation, she was diagnosed with immune thrombocytopenic purpura and was also found to have elevated free T3 and T4, and suppressed thyroid stimulating hormone. She also had high thyroid autoantibodies. She was initially started on oral prednisolone but there was no stabilization of platelets until methimazole was introduced, which improved and normalized her platelet count. CONCLUSION: The association of Graves' disease with immune thrombocytopenic purpura, though documented, is uncommon, and very few cases have been reported thus far. There have not been any reported cases in Ghana or Sub-Saharan Africa and hence, clinicians should be aware of this association when investigating immune thrombocytopenic purpura and should consider Graves' disease as a possible cause. From this study, we observed that there was no improvement in platelet count following the use of corticosteroid therapy until methimazole was started.


Assuntos
Doença de Graves , Púrpura Trombocitopênica Idiopática , Trombocitopenia , Humanos , Feminino , Adulto , Púrpura Trombocitopênica Idiopática/complicações , Púrpura Trombocitopênica Idiopática/diagnóstico , Púrpura Trombocitopênica Idiopática/tratamento farmacológico , Metimazol/uso terapêutico , Gana , Doença de Graves/complicações , Doença de Graves/tratamento farmacológico , Trombocitopenia/complicações
5.
BMC Cardiovasc Disord ; 23(1): 82, 2023 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-36765294

RESUMO

BACKGROUND: Heart failure (HF) is recognized as a global public health disease associated with high morbidity and mortality. It is suggested that the main underlying causes of HF in developing countries differ from those identified in well-resourced countries. This study therefore presents the cardiovascular risk factors and the underlying aetiology of HF among admitted patients in a teaching Hospital in Ghana. METHOD: The study prospectively recruited 140 consecutive patients admitted for heart failure at the Medical department of the Korle-Bu Teaching Hospital from March to October, 2014. The study evaluated the cardiovascular risk factors and the aetiologies of heart failure, and compared the risk factors and aetiologies with patient's age and gender. RESULTS: The mean age of the study participants was 51.3 ± 16.8 years. The commonest cardiovascular risk factors observed were hypertension (46.5%), history of previous HF (40.7%), excessive alcohol use (38.6%), and family history of heart disease (29.3%); predominantly hypertension (68.3%). The major underlying aetiology of HF were dilated cardiomyopathy (38.6%), hypertensive heart disease (21.4%), ischaemic heart disease (13.6%) and valvular heart disease (12.9%). These underlying aetiology of HF were more common in patients aged 40 years and above (p = 0.004) and those presenting with multiple risk factors (p = 0.001). CONCLUSION: The major underlying aetiology of heart failure in adults were dilated cardiomyopathy, hypertensive heart disease, ischaemic heart disease and valvular heart disease, which were significantly high among patients aged 40 years and above and those presenting multiple risk factors. Hypertension, excessive alcohol use, family history of heart disease and personal history of previous heart failure diagnosis are noted as the main cardiovascular risk factors among heart failure patients.


Assuntos
Cardiomiopatia Dilatada , Doença da Artéria Coronariana , Insuficiência Cardíaca , Doenças das Valvas Cardíacas , Hipertensão , Isquemia Miocárdica , Adulto , Humanos , Pessoa de Meia-Idade , Idoso , Cardiomiopatia Dilatada/diagnóstico , Cardiomiopatia Dilatada/epidemiologia , Cardiomiopatia Dilatada/complicações , Gana/epidemiologia , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/etiologia , Hipertensão/diagnóstico , Hipertensão/epidemiologia , Hipertensão/complicações , Isquemia Miocárdica/complicações , Hospitais de Ensino , Doenças das Valvas Cardíacas/complicações , Doença da Artéria Coronariana/complicações
6.
Am J Primatol ; 83(12): e23338, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34662462

RESUMO

Species distributions are influenced by processes occurring at multiple spatial scales. It is therefore insufficient to model species distribution at a single geographic scale, as this does not provide the necessary understanding of determining factors. Instead, multiple approaches are needed, each differing in spatial extent, grain, and research objective. Here, we present the first attempt to model continent-wide great ape density distribution. We used site-level estimates of African great ape abundance to (1) identify socioeconomic and environmental factors that drive densities at the continental scale, and (2) predict range-wide great ape density. We collated great ape abundance estimates from 156 sites and defined 134 pseudo-absence sites to represent additional absence locations. The latter were based on locations of unsuitable environmental conditions for great apes, and on existing literature. We compiled seven socioeconomic and environmental covariate layers and fitted a generalized linear model to investigate their influence on great ape abundance. We used an Akaike-weighted average of full and subset models to predict the range-wide density distribution of African great apes for the year 2015. Great ape densities were lowest where there were high Human Footprint and Gross Domestic Product values; the highest predicted densities were in Central Africa, and the lowest in West Africa. Only 10.7% of the total predicted population was found in the International Union for Conservation of Nature Category I and II protected areas. For 16 out of 20 countries, our estimated abundances were largely in line with those from previous studies. For four countries, Central African Republic, Democratic Republic of the Congo, Liberia, and South Sudan, the estimated populations were excessively high. We propose further improvements to the model to overcome survey and predictor data limitations, which would enable a temporally dynamic approach for monitoring great apes across their range based on key indicators.


Assuntos
Hominidae , África Central , África Ocidental , Animais , República Centro-Africana , Coleta de Dados , Gorilla gorilla , Pan troglodytes
7.
JCO Glob Oncol ; 7: 173-182, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33529076

RESUMO

PURPOSE: Underdeveloped nations carry the burden of most cervical cancer, yet access to adequate treatment can be challenging. This report assesses the current management of cervical cancer in sub-Saharan Africa to better understand the needs of underdeveloped nations in managing cervical cancer. METHODS: A pre- and postsurvey was sent to all centers participating in the Cervical Cancer Research Network's 4th annual symposium. The pre- and postsurvey evaluated human papillomavirus and HIV screening, resources available for workup and/or treatment, treatment logistics, outcomes, and enrollment on clinical trials. Descriptive analyses were performed on survey responses. RESULTS: Twenty-nine centers from 12 sub-Saharan countries saw approximately 300 new cases of cervical cancer yearly. Of the countries surveyed, 55% of countries had a human papillomavirus vaccination program and 30% (range, 0%-65%) of women in each region were estimated to have participated in a cervical cancer screening program. In the workup of patients, 43% of centers had the ability to obtain a positron emission tomography and computed tomography scan and 79% had magnetic resonance imaging capabilities. When performing surgery, 88% of those centers had a surgeon with an expertise in performing oncological surgeries. Radiation therapy was available at 96% of the centers surveyed, and chemotherapy was available in 86% of centers. Clinical trials were open at 4% of centers. CONCLUSION: There have been significant advancements being made in screening, workup, and management of patients with cervical cancer in sub-Saharan Africa; yet, improvement is still needed. Enrollment in clinical trials remains a struggle. Participants would like to enroll patients on clinical trials with Cervical Cancer Research Network's continuous support.


Assuntos
Infecções por Papillomavirus , Vacinas contra Papillomavirus , Neoplasias do Colo do Útero , África Subsaariana/epidemiologia , África do Norte , Ensaios Clínicos como Assunto , Detecção Precoce de Câncer , Feminino , Humanos , Infecções por Papillomavirus/diagnóstico , Infecções por Papillomavirus/terapia , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/terapia
8.
Chemosphere ; 261: 127690, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32736243

RESUMO

The concentration of cosmogenic radionuclide 7Be and the naturally occurring radionuclide 222Rn and its progenies 210Pb, 210Po, and 214Pb were measured in the ground surface air in the urban area of the northern Arabian Gulf close to Kuwait Bay. A high-volume air sampler connected with a five-stage cascade impactor was used to collect approximately 1800 cubic meter weekly for a period of one year. The concentrations of 210Pb and 210Po varied from 0.35 to 1.65 mBq m-3 and from 0.23 to 3.2 mBq m-3, respectively; the 210Po/210Pb activity ratio was close to one. The average concentration of 7Be was 6.24 mBq m-3, ranging from 3 to 10 mBq m-3. The temporal variations of 210Pb, 210Po and 7Be showed maximum concentrations of 210Po and 7Be in occurred summer months. The observed excess of 210Po concentrations can be attributed to the local and long-range transport of suspended dust with 210Pb and 210Po in radioactive equilibrium state, oil industry emissions, local resuspended dust and the sea-salt-aerosols from the Arabian Gulf. The range of the residence time estimation using the 222Rn/210Pb and 214Pb/210Pb activity ratio methods ranged from three to five days. Moreover, the estimated residence time by the application of 7Be from the activity median aerodynamic diameter method was 4.2 days. The method of using the 210Po/210Pb activity ratio was invalid because of the excess 210Po sources of anthropogenic origin. Therefore, extensive accurate diurnal measurements of 214Pb and 222Rn can be applied in hot arid regions for better aerosols residence time estimation.


Assuntos
Poluentes Radioativos do Ar/análise , Polônio/análise , Monitoramento de Radiação , Aerossóis/análise , Baías , Poeira , Kuweit , Radioatividade , Radioisótopos , Estações do Ano
9.
J Environ Radioact ; 192: 565-572, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29885903

RESUMO

For many years, monitoring and determining the radioactivity of 137Cs in the environment has considerable interest. This paper presents monitoring 137Cs deposition fluxes during the period from 2009 to 2011. Dust fallout samples were collected from ten locations in Kuwait, and 137Cs concentrations were determined using ultra low spectrometry system. The average of the annual atmospheric deposition fluxes of 137Cs was 4.3, with an extreme value reaching 50 Bq m-2. The monthly deposition rates of 137Cs were attributed to seasonal increases in the spring. 137Cs deposition fluxes showed a significant relationship with dust deposition and precipitation rates, where the correlation between the monthly dust fallout and the 137Cs deposition fluxes and precipitation rates were approximately 0.95 and 0.81, respectively. The spatial monthly distribution of 137Cs fluxes showed high rates in the southeastern part of Kuwait while the lowest rates were recorded along the coastlines. A strong correlation was observed between the annual 137Cs and 40K deposition rates considering that both radionuclides deposition were governed by similar conditions. It was concluded that long-range transport from the northwestern areas along with the effects from local dust washout and the site specify played a major role in controlling the rate of 137Cs deposition. The estimated annual effective dose equivalent due to external and internal exposures was insignificant and can be ignored. It is worthwhile to continue investigating the source origin of 137Cs in Kuwait to enhance understanding of the radiological hazards in the country.


Assuntos
Poluentes Radioativos do Ar/análise , Radioisótopos de Césio/análise , Poeira/análise , Monitoramento de Radiação , Cinza Radioativa/análise , Kuweit , Estações do Ano
10.
Sci Adv ; 4(4): eaar2964, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29707637

RESUMO

We present a range-wide assessment of sympatric western lowland gorillas Gorilla gorilla gorilla and central chimpanzees Pan troglodytes troglodytes using the largest survey data set ever assembled for these taxa: 59 sites in five countries surveyed between 2003 and 2013, totaling 61,000 person-days of fieldwork. We used spatial modeling to investigate major drivers of great ape distribution and population trends. We predicted density across each taxon's geographic range, allowing us to estimate overall abundance: 361,900 gorillas and 128,700 chimpanzees in Western Equatorial Africa-substantially higher than previous estimates. These two subspecies represent close to 99% of all gorillas and one-third of all chimpanzees. Annual population decline of gorillas was estimated at 2.7%, maintaining them as Critically Endangered on the International Union for Conservation of Nature and Natural Resources (IUCN) Red List. We quantified the threats to each taxon, of which the three greatest were poaching, disease, and habitat degradation. Gorillas and chimpanzees are found at higher densities where forest is intact, wildlife laws are enforced, human influence is low, and disease impacts have been low. Strategic use of the results of these analyses could conserve the majority of gorillas and chimpanzees. With around 80% of both subspecies occurring outside protected areas, their conservation requires reinforcement of anti-poaching efforts both inside and outside protected areas (particularly where habitat quality is high and human impact is low), diligent disease control measures (including training, advocacy, and research into Ebola virus disease), and the preservation of high-quality habitat through integrated land-use planning and implementation of best practices by the extractive and agricultural industries.


Assuntos
Armas de Fogo , Gorilla gorilla , Pan troglodytes , Árvores , África , Animais , Geografia , Modelos Teóricos , Densidade Demográfica , Dinâmica Populacional
11.
Parasit Vectors ; 11(1): 175, 2018 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-29530100

RESUMO

BACKGROUND: Plasmodium falciparum delayed clearance with the use of artemisinin-based combination therapy (ACTs) has been reported in some African countries. Single nucleotide polymorphisms (SNPs) in two genes, P. falciparum adaptor protein complex 2 mu subunit (pfap2mu) and ubiquitin specific protease 1 (pfubp1), have been linked to delayed clearance with ACT use in Kenya and recurrent imported malaria in Britain. With over 12 years of ACT use in Ghana, this study investigated the prevalence of SNPs in the pfap2mu and pfubp1 in Ghanaian clinical P. falciparum isolates to provide baseline data for antimalarial drug resistance surveillance in the country. METHODS: Filter paper blood blots collected in 2015-2016 from children aged below 9 years presenting with uncomplicated malaria at hospitals in three sentinel sites Begoro, Cape Coast and Navrongo were used. Parasite DNA was extracted from 120 samples followed by nested polymerase chain reaction (nPCR). Sanger sequencing was performed to detect and identify SNPs in pfap2mu and pfubp1 genes. RESULTS: In all, 11.1% (9/81) of the isolates carried the wildtype genotypes for both genes. A total of 164 pfap2mu mutations were detected in 67 isolates whilst 271 pfubp1 mutations were observed in 72 isolates. The majority of the mutations were non-synonymous (NS): 78% (128/164) for pfap2mu and 92.3% (250/271) for pfubp1. Five unique samples had a total of 215 pfap2mu SNPs, ranging between 15 and 63 SNPs per sample. Genotypes reportedly associated with ART resistance detected in this study included pfap2mu S160N (7.4%, 6/81) and pfubp1 E1528D (7.4%, 6/81) as well as D1525E (4.9%, 4/81). There was no significant difference in the prevalence of the SNPs between the three ecologically distinct study sites (pfap2mu: χ2 = 6.905, df = 2, P = 0.546; pfubp1: χ2 = 4.883, df = 2, P = 0.769). CONCLUSIONS: The detection of pfap2mu and pfubp1 genotypes associated with ACT delayed parasite clearance is evidence of gradual nascent emergence of resistance in Ghana. The results will serve as baseline data for surveillance and the selection of the genotypes with drug pressure over time. The pfap2mu S160N, pfubp1 E1528D and D1525E must be monitored in Ghanaian isolates in ACT susceptibility studies, especially when cure rates of ACTs, particularly AL, is less than 100%.


Assuntos
Complexo 2 de Proteínas Adaptadoras/genética , Resistência a Medicamentos/genética , Plasmodium falciparum/genética , Polimorfismo de Nucleotídeo Único/genética , Proteínas de Ligação a RNA/genética , Proteases Específicas de Ubiquitina/genética , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Artemisininas/efeitos adversos , Artemisininas/uso terapêutico , Criança , Pré-Escolar , Feminino , Genótipo , Gana/epidemiologia , Humanos , Lactente , Malária Falciparum/tratamento farmacológico , Malária Falciparum/epidemiologia , Malária Falciparum/parasitologia , Masculino , Mutação , Plasmodium falciparum/isolamento & purificação , Prevalência
12.
J Interv Cardiol ; 31(1): 23-30, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28929594

RESUMO

OBJECTIVES: This study set out to identify significant lesion features of chronic total occlusion (CTO) that predict successful retrograde recanalization via epicardial collateral channels (CCs). BACKGROUND: Epicardial CCs remain essential in retrograde percutaneous coronary intervention (PCI) of CTO. However, the unpredictability of success and occurrence of complications limit the application of epicardial CCs for retrograde PCI technique for CTO. METHODS: 103 retro-recanalization cases were analyzed using epicardial CCs with successful recanalization as an end point. Clinical and angiography data were collected. RESULTS: The total success rate was 76.3%. Independent predictors associated with technical success included CCs tortuosity, side branch at CCs tortuosity, inadequate CCs Size and inadequate CCs exit location. Assigning a score of one for each variable, four levels of difficulty were obtained and formed the EPI-CTO score (Epicardial CTO). This score had significant predictive value for the likelihood of successful recanalization (AUC: 0.94, 95%CI: 0.89-0.98). Coronary and CCs perforation occurred in 6 and 10 cases respectively. Four cases including two coronary and two CCs perforations had tamponade that needed pericardiocentesis. CONCLUSIONS: Using epicardial CCs for retrograde approach of CTO PCI is effective. Complication rate was acceptable. We found four independent predictors relative to procedure success.


Assuntos
Circulação Colateral , Oclusão Coronária , Intervenção Coronária Percutânea , Complicações Pós-Operatórias , Idoso , Doença Crônica , Angiografia Coronária/métodos , Oclusão Coronária/diagnóstico , Oclusão Coronária/patologia , Oclusão Coronária/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Processos e Resultados em Cuidados de Saúde , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/métodos , Pericárdio/diagnóstico por imagem , Pericárdio/cirurgia , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/prevenção & controle , Valor Preditivo dos Testes , Prognóstico , Falha de Tratamento , Resultado do Tratamento
13.
Mar Pollut Bull ; 123(1-2): 365-372, 2017 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-28899599

RESUMO

This study focuses on creating baseline for 238U, 235U, 234U, 210Pb, 210Po and 40K concentrations in the northern Arabian Gulf. The respective concentration ranges were 0.047-0.050, 0.00186-0.00198, 0.054-0.057, 0.00085-0.00092, 0.00051-0.00062 and 18.6-19.1Bql-1. These results suggest that the levels are generally comparable to other marine waters in the northern hemisphere. There were no hot spots observed from oil and gas industry. These data will serve as a baseline to gauge possible future inputs of TENORMs in the northern Gulf. A positive and linear correlation was observed between 238,234U, 40K isotopes and seawater salinity. The results also suggest significant fractionation between 210Po and 210Pb, attributed to rapid removal of 210Po by biota compared to 210Pb. The mean residence time for 210Po in the study area was 371days. The 234U/238U and 238U/235U activity ratios in seawater samples vary between 1.14-1.15, and 0.038-0.040. The 234U/238U and 235U/238U ratio is similar to the expected composition of seawater (1.148±0.002) and 0.0462.


Assuntos
Radioisótopos de Chumbo/análise , Polônio/análise , Radioisótopos de Potássio/análise , Urânio/análise , Biota/fisiologia , Oceano Índico , Kuweit , Monitoramento de Radiação/métodos , Salinidade , Água do Mar/química
14.
Mar Pollut Bull ; 120(1-2): 396-400, 2017 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-28487058

RESUMO

The Arabian Gulf is a semi-enclosed water body that has witnessed accelerated anthropogenic activity, in terms of commissioning of nuclear power plants, desalination facilities, oil refineries and extensive coastal development. Furthermore, three wars during the past three decades is a potential worry. This study presents the first plutonium baseline in seawater from the Northern Arabian Gulf. The 239+240Pu concentrations in seawater vary, between 2.9 and 4.9mBqm-3, a range that is comparable to other water masses at this latitude. The 238Pu ranged between 0.04 and 0.05mBqm-3 and the 137Cs concentration between 1.04 and 1.18Bqm-3. The ratio of 238Pu/239+240Pu at all eight sampling stations was 0.01, while the ratio of 239+240Pu/137Cs varied between 0.01 and 0.02. The presence of 137Cs and 239+240Pu in seawater from this region can mainly be attributed to the global atmospheric deposition and fluvial transport. The seawater concentration of 239+240Pu is five order of magnitude lower than bottom sediments in the area.


Assuntos
Césio/análise , Plutônio/análise , Poluentes Radioativos da Água/análise , Radioisótopos de Césio , Sedimentos Geológicos , Oriente Médio , Água do Mar
15.
Mar Pollut Bull ; 100(2): 651-61, 2015 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-26490408

RESUMO

The Arabian Gulf region is moving towards a nuclear energy option with the first nuclear power plant now operational in Bushehr, Iran, and others soon to be constructed in Abu Dhabi and Saudi Arabia. Radiological safety is becoming a prime concern in the region. This study compiles available data and presents recent radionuclide data for the northern Gulf waters, considered as pre-nuclear which will be a valuable dataset for future monitoring work in this region. Radionuclide monitoring in the marine environment is a matter of prime concern for Kuwait, and an assessment of the potential impact of radionuclides requires the establishment and regular updating of baseline levels of artificial and natural radionuclides in various environmental compartments. Here we present baseline measurements for (210)Po, (210)Pb, (137)Cs, (90)Sr, and (3)H in Kuwait waters. The seawater concentration of (3)H, (210)Po, (210)Pb, (137)Cs, and (90)Sr vary between 130-146, 0.48-0.68, 0.75-0.89, 1.25-1.38 and 0.57-0.78 mBq L(-1), respectively. The (40)K concentration in seawater varies between 8.9-9.3 Bq L(-1). The concentration of (40)K, total (210)Pb, (137)Cs, (90)Sr, (226)Ra, (228)Ra, (238)U, (235)U, (234)U, (239+240)Pu and (238)Pu were determined in sediments and range, respectively, between 353-445, 23.6-44.3, 1.0-3.1, 4.8-5.29, 17.3-20.5, 15-16.4, 28.7-31.4, 1.26-1.30, 29.7-30.0, 0.045-0.21 and 0.028-0.03 Bq kg(-1) dry weight. Since, radionuclides are concentrated in marine biota, a large number of marine biota samples covering several trophic levels, from microalgae to sharks, were analyzed. The whole fish concentration of (40)K, (226)Ra, (224)Ra, (228)Ra, (137)Cs, (210)Po and (90)Sr range between 230-447, 0.7-7.3, <0.5-6.6, <0.5-15.80, <0.17, 0.88-4.26 and 1.86-5.34 Bq kg(-1) dry weight, respectively. (210)Po was found to be highly concentrated in several marine organisms with the highest (210)Po concentration found in Marica marmorata (193.5-215.6 Bq kg(-1) dry weight). (210)Po in most dissected fish samples shows increasing concentrations in the following order: edible tissue, gills, digestive system, liver and fecal matter. Fish fecal pellets had (210)Po concentrations several orders of magnitude higher than the seawater, fish muscle, and the fishes' ingested food. The high (210)Po concentration in fish fecal matter, suggest that the bulk of (210)Po content in fish was eventually excreted back into the environment as fecal pellets. In most fish high concentrations were noted in liver, with the highest (210)Po concentration recorded in shark liver (126.2-141.5 Bq kg(-1) wet). Moreover, (210)Po concentration in the soft tissue of molluscs (10.36-215.60 Bq kg(-1) dry weight) was far higher than that in fish muscle (0.05-7.49 Bq kg(-1) wet weight). A seasonal drop in (210)Po concentration in seawater was observed to vary with the abundance of phytoplankton and macroalgae due possibly to biological dilution. (137)Cs concentration in all the fish sampled was below the detection limit, and the concentration in seawater was also low; hence such low levels provide an opportunity to use this radionuclide as an indicator for any future radiocesium releases in this region.


Assuntos
Peixes , Fitoplâncton/química , Poluentes Radioativos da Água/análise , Animais , Radioisótopos de Césio/análise , Contaminação Radioativa de Alimentos/análise , Kuweit , Radioisótopos de Chumbo/análise , Moluscos/metabolismo , Polônio/análise , Polônio/farmacocinética , Alimentos Marinhos/análise , Estações do Ano , Água do Mar , Tubarões/metabolismo , Radioisótopos de Estrôncio/análise , Distribuição Tecidual , Poluentes Radioativos da Água/farmacocinética
16.
Mar Pollut Bull ; 90(1-2): 330-3, 2015 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-25440188

RESUMO

This baseline study highlights the (210)Po and (210)Pb concentration in two species of the benthic macroalgae Sargassum from northern Gulf, also known as the ROPME Sea Area (RSA). Within the marine environment, (210)Po is initially absorbed from water and concentrated by phytoplankton and macroalgae, and this concentrated (210)Po can then readily be passed along to the higher trophic level of the marine food web. The (210)Po concentration measured in Sargassum boveanum (22.5-25.6 Bq kg(-1)) was higher than that in Sargassum oligocystum (20.2-22.5 Bq kg(-1)), but is not statistically significant (p>0.064), where as the difference between (210)Pb concentrations in Sargassum boveanum (15.3-16.8 Bq kg(-1)) and Sargassum oligocystum (18.4-22.0 Bq kg(-1)) was statistically significant (p>0.019). The measured concentration factor for (210)Po in Sargassum in the northern Gulf varied between 0.55 and 1.2×10(4), values higher to the IAEA recommended value of 1×10(3). The (210)Po enrichment is observed in both the species of Sargassum,(210)Po/(210)Pb ratio was >1 at all the stations for all the samples.


Assuntos
Radioisótopos de Chumbo/análise , Polônio/análise , Monitoramento de Radiação , Sargassum/química , Cadeia Alimentar , Kuweit , Água do Mar/química
17.
PLoS One ; 8(3): e59469, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23469289

RESUMO

African forest elephants- taxonomically and functionally unique-are being poached at accelerating rates, but we lack range-wide information on the repercussions. Analysis of the largest survey dataset ever assembled for forest elephants (80 foot-surveys; covering 13,000 km; 91,600 person-days of fieldwork) revealed that population size declined by ca. 62% between 2002-2011, and the taxon lost 30% of its geographical range. The population is now less than 10% of its potential size, occupying less than 25% of its potential range. High human population density, hunting intensity, absence of law enforcement, poor governance, and proximity to expanding infrastructure are the strongest predictors of decline. To save the remaining African forest elephants, illegal poaching for ivory and encroachment into core elephant habitat must be stopped. In addition, the international demand for ivory, which fuels illegal trade, must be dramatically reduced.


Assuntos
Conservação dos Recursos Naturais , Crime/economia , Elefantes/fisiologia , África Central , Animais , Conservação dos Recursos Naturais/tendências , Crime/estatística & dados numéricos , Ecossistema , Humanos , Densidade Demográfica , Fatores Socioeconômicos , Árvores
18.
Mar Pollut Bull ; 64(11): 2599-602, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22863352

RESUMO

This baseline study highlights the (210)Po variation in whole fishes with different feeding habits. Whole-body (210)Po concentrations were determined in ten important commercial fish species found in the northern Arabian Gulf to serve as baseline data. Primarily, (210)Po is absorbed from water, concentrated by phytoplankton and microzooplankton, and then transferred to the next trophic level along the marine food chain. The lowest concentration of (210)Po was measured in larger carnivorous fishes like hamoor (0.089 Bq kg(-1)), while the highest was found in the fishes that feed on algae, zooplanktons and detritus, like battan (3.30 Bq kg(-1)). The baseline data can be used to understand both the trophic transfer of (210)Po in the marine food chain and the (210)Po concentration factors in fish from the Arabian Gulf.


Assuntos
Peixes/metabolismo , Polônio/metabolismo , Monitoramento de Radiação , Poluentes Radioativos da Água/metabolismo , Animais , Cadeia Alimentar , Kuweit , Fitoplâncton/metabolismo , Medição de Risco , Alimentos Marinhos/estatística & dados numéricos , Zooplâncton/metabolismo
19.
Artigo em Inglês | MEDLINE | ID: mdl-19964239

RESUMO

Previous works on the effects of salivary alpha amylase in respond to various stressors report encouraging findings on it being a good indicator of stress. Ellestad protocol is a clinical procedure to screen for coronary artery disease by introducing exercise induced physical stress. If a salivary based biomarker profile in accordance to a stress test protocol could be established, the critical stress state which disable rational decision making could be ascertained in a standardized procedure. This technique would serve to aid human resource management in times of critical events such as rescue, firefighting or even military, that would potentially prevent unnecessary sacrifice of human lives. In this pilot study with five healthy volunteers performing the Ellestad protocol treadmill, a measurement profile with physiologic and salivary based biomarker is obtained. It is found that the alpha amylase levels or the changes in it as workload changes from resting-walking-running at ease-exhaustive running, is relatively more significant in reflecting the stress state than heart rate and blood pressure. Moreover, it is strongly associated with mood state with correlation coefficient of 0.8 and significance of 0.01.


Assuntos
Teste de Esforço/métodos , Saliva/metabolismo , Estresse Psicológico/diagnóstico , alfa-Amilases/análise , Adolescente , Adulto , Biomarcadores/análise , Pré-Escolar , Feminino , Humanos , Masculino , Adulto Jovem
20.
Appl Radiat Isot ; 63(4): 457-63, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16005239

RESUMO

Evaluation has been made of the distribution of hard scales containing naturally occurring radioactive materials (NORM) in a range of oilfield equipment in Syrian oilfields. One hundred and fifty-two scale samples from oilfield equipment were collected and analysed for radioactivity, elemental and mineralogical compositions. The average 226Ra, 228Ra and 224Ra concentrations in scales were found to be 174, 91 and 67 Bqg(-1), respectively; the highest value of 226Ra was found to be 1520 Bqg(-1). A gradual increase in 226Ra specific activity from down-hole tubulars to surface parts of the installations was observed. The 228Ra/226Ra mean activity ratio was observed to be 0.76, indicating a Th/U mass ratio of about 2.3. This value can be considered a fingerprint for the Th/U mass ratio of the geological formation of the reservoir. Radium isotopic data were also used to estimate the age of the deposited scales using the 224Ra/228Ra activity ratio; the highest average age (5.3 years) was found to be in scales collected from valves. Multiple regressions of the data have shown that 226Ra is more highly correlated with Ba and Sr content in scales (R2=0.92) than Ca. Around 77% of 226Ra was found to be incorporated with anhydrate barium strontium sulphate (R2=0.93), solubility in water being very low to negligible; lower levels of radium isotopes were found in calcite.

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