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1.
S Afr Med J ; 112(8): 522-525, 2022 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-36214394

RESUMO

BACKGROUND: Ivermectin is an antiparasitic drug that has shown in vitro activity against COVID­19. Clinical studies supporting ivermectin for COVID­19 prevention and treatment are conflicting, with important limitations. Public support for ivermectin is significant, with extensive off-label use despite the conflicting views on its efficacy. Ivermectin tablets and injectable formulations are not registered in South Africa for human use by the South African Health Products Regulatory Authority. The National Department of Health does not currently recommend the use of ivermectin for COVID­19. OBJECTIVES: To describe cases of ivermectin exposure reported to the Poisons Information Helpline of the Western Cape (PIHWC) before and after publication of the drug's in vitro activity against SARS-CoV-2. METHODS: In a retrospective review, ivermectin-related calls reported to the PIHWC from 1 June 2015 to 30 June 2020 (period 1) were compared with calls received from 1 July 2020 to 31 July 2021 (period 2), dichotomised according to the first publication indicating ivermectin activity against SARS-CoV-2. RESULTS: Seventy-one cases were screened, and 65 were included for analysis; 19 cases were reported during period 1 and 46 during period 2. During period 2, 25 ivermectin cases (54.3%) were related to COVID­19 use. Of these, 24 cases (52.2%) involved veterinary preparations, 3 (6.5%) human preparations and 19 (41.3%) unknown preparations. Fourteen cases (73.7%) during period 1 and 30 (65.2%) during period 2 were reported to be symptomatic. The most common organ systems involved were the central nervous (n=26 cases; 40.0%), gastrointestinal (n=18; 27.7%), ocular (n=9; 13.8%) and dermatological (n=5; 7.7%) systems. CONCLUSION: Ivermectin-related exposure calls increased during study period 2, probably as a result of ivermectin being used as preventive and definitive therapy for COVID­19 in the absence of robust evidence on efficacy, dosing recommendations or appropriate formulations.


Assuntos
COVID-19 , Venenos , Antiparasitários/uso terapêutico , Humanos , Ivermectina/uso terapêutico , Pandemias/prevenção & controle , SARS-CoV-2 , África do Sul/epidemiologia
2.
J Environ Radioact ; 237: 106692, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34237508

RESUMO

The use of nuclear power as an environmentally friendly, and sustainable means for energy production is heavily under discussion. Despite this recently several countries with a predominantly arid climate have sought to develop or deploy nuclear energy production systems. However, there is little information on how radionuclides behave in different, especially arid, climates. Members of the IUR task group for arid environment and of the IAEA MODARIA II working group 4 contributed to such a supplement to the International Atomic Energy Agency (IAEA) Technical Report Series No. 472 (IAEA, 2010) Handbook of Parameter Values for the Prediction of Radionuclides Transfer in Terrestrial and Freshwater Environments under the IAEA Modelling and Data for Radiological Impact Assessments (MODARIA II) programme (2016-2019) to close this knowledge gap. Data on concentration ratios for plant and soil (CR) in arid environments following the Köppen-Geiger classification of climates were collated, summarised and quality assured. The combination of this data with transfer parameter data for root uptake of radionuclides by food crops in tropical environments (this issue) aimed to compare all data with those in TRS 472 recommended for use in dose assessment models. Therefore, a databank has been started based on an intensive literature research on published concentration ratio (CR) data in selected arid environments. After quality check data have been formatted to comply with TRS 472 and with the tropical data base criteria. Due to the scarcity of published information and the high uncertainty of the estimated mean values for individual plant and soil groups in arid environments no statistically relevant conclusions could be drawn, although some differences were notable. Nevertheless, despite its limitations and high uncertainties, this work presents the first reported comprehensive data collation on CR soil-plant values in arid environments.


Assuntos
Monitoramento de Radiação , Poluentes Radioativos do Solo , Plantas , Radioisótopos/análise , Solo , Poluentes Radioativos do Solo/análise
4.
Pediatr Surg Int ; 35(11): 1217-1222, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31346695

RESUMO

INTRODUCTION: Biliary atresia is a rare neonatal disease and the most common indication for pediatric liver transplantation. Kasai portoenterostomy is the initial treatment, aiming to prevent liver transplantation. Beyond age at Kasai, few prognostic factors are known. Multiple countries have established screening methods to reduce the age at Kasai and recent analysis shows significant better outcomes for screening cohorts. In 2016, we established a decentralized stool color card screening in Lower Saxony and we present our first 2 years of experiences. METHODS: In cooperation with a major German health insurance company and the Medical Association of Lower Saxony, we established the screening project, printed 120,000 color cards, and distributed them to all maternity hospitals. Program advertises were printed in newspapers and medical journals. After the first year, the project was evaluated. Thirty maternity hospitals and local practitioners were contacted via telephone, Internet, intranet, and pediatric journals. RESULTS: One out of seventy-six maternity hospitals (1.3%) refused to participate in the screening. 30 hospitals (40%) were contacted and 93.5% of the interviewed staff reported that stool color cards were handed out regularly and discussed with the parents. Only 20% of local practitioners assessed neonatal cholestasis to be a relevant problem during daily practice, and 55% regarded a stool color card screening to be useful. CONCLUSIONS: In the second year, we extended the screening project to outpatient maternity clinics. Based on the responses of local practitioners, we regard the voluntary screening as insufficient and we have contacted the Federal Joint Committee for the initiation of a nationwide obligatory stool color card screening.


Assuntos
Atresia Biliar/diagnóstico , Cor , Fezes , Triagem Neonatal , Instituições de Assistência Ambulatorial , Feminino , Alemanha , Política de Saúde , Maternidades , Humanos , Lactente , Recém-Nascido , Masculino , Padrões de Prática Médica/estatística & dados numéricos
5.
J Environ Radioact ; 157: 77-89, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27018344

RESUMO

April 2016 sees the 30(th) anniversary of the accident at the Chernobyl nuclear power plant. As a consequence of the accident populations were relocated in Belarus, Russia and Ukraine and remedial measures were put in place to reduce the entry of contaminants (primarily (134+137)Cs) into the human food chain in a number of countries throughout Europe. Remedial measures are still today in place in a number of countries, and areas of the former Soviet Union remain abandoned. The Chernobyl accident led to a large resurgence in radioecological studies both to aid remediation and to be able to make future predictions on the post-accident situation, but, also in recognition that more knowledge was required to cope with future accidents. In this paper we discuss, what in the authors' opinions, were the advances made in radioecology as a consequence of the Chernobyl accident. The areas we identified as being significantly advanced following Chernobyl were: the importance of semi-natural ecosystems in human dose formation; the characterisation and environmental behaviour of 'hot particles'; the development and application of countermeasures; the "fixation" and long term bioavailability of radiocaesium and; the effects of radiation on plants and animals.


Assuntos
Acidente Nuclear de Chernobyl , Animais , Fenômenos Ecológicos e Ambientais , Recuperação e Remediação Ambiental , Contaminação Radioativa de Alimentos , Humanos , Monitoramento de Radiação , Poluentes Radioativos , Ucrânia
7.
J Environ Radioact ; 132: 8-14, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24508949

RESUMO

The transfer of (137)Cs, (85)Sr, (131)I, (210)Po, (210)Pb and (238)U from feed to camel's milk was investigated in a pilot experiment with three lactating camels. For a period of 60 days, the animals were fed on spiked feed containing the studied radionuclides. They were subsequently returned to a contamination-free diet and monitored for another 90 days. The activity concentrations of (137)Cs, (85)Sr and (131)I in milk decreased with time and reached background levels after 20 days. Equilibrium transfer coefficients and biological half-lives were estimated and transfer coefficients were calculated as (8.1 ± 3.6) × 10(-4), (4.4 ± 1.6) × 10(-2), (7.8 ± 3.9) × 10(-4), (2.7 ± 3.5) × 10(-4), (1.8 ± 1.5) × 10(-4) and (7.0 ± 3.6) × 10(-3) d L(-1) for (85)Sr, (131)I, (137)Cs, (210)Po, (210)Pb and (238)U, respectively. The biological half-lives were estimated to be 6.4, 4.2, 8.9, and 53.3 days for (85)Sr, (131)I, (137)Cs, and (238)U, respectively. Estimates of the half-lives were based on a one component model: it was found that the half-life values measured for artificial radionuclides were slightly shorter than those for natural radionuclides. The data obtained in the study are the first published experimental data on radionuclide transfer to camel milk.


Assuntos
Ração Animal/análise , Contaminação Radioativa de Alimentos/análise , Lactação/efeitos da radiação , Leite/química , Monitoramento de Radiação/métodos , Radioisótopos/análise , Animais , Camelus , Radioisótopos de Césio/análise , Feminino , Radioisótopos de Chumbo/análise , Polônio/análise , Radioisótopos de Estrôncio/análise , Fatores de Tempo
8.
Neuroscience ; 240: 98-105, 2013 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-23466808

RESUMO

Recent functional imaging studies that examined functional connectivity in the resting brain have demonstrated various intrinsic connectivity networks (ICNs). Certain patterns of over- and underactivity in various ICNs have been hypothesized to form the neural basis of psychiatric disorders. Furthermore, activity in the ICNs does not reflect ongoing mental activity but the maintenance of neural circuits in a ready state suggesting not only relationships between ICNs and disorders but also correlations between ICNs and personality. In the present study, we assess the relationship between trait anxiety, a well established endophenotype of anxiety disorders, and functional connectivities within the insular salience ICN in a sample of healthy female subjects. Based on a previous study that demonstrated the functional relevance of the insular salience ICN for state anxiety, we used the harm avoidance scale from the Temperament and Character Inventory (TCI) as a trait marker to demonstrate increased functional connectivity within the insular salience ICN. Specifically, the functional connectivity between the anterior insula and the anterior cingulate and between the anterior insula and the dorsolateral prefrontal cortex were positively correlated with individual harm avoidance scores. The results fit into previous work, provide evidence for a potential biomarker of anxiety disorders and, most importantly, demonstrate a direct neural correlate of the personality trait harm avoidance in the absence of external stimulation.


Assuntos
Mapeamento Encefálico , Encéfalo/fisiologia , Redução do Dano/fisiologia , Vias Neurais/fisiologia , Descanso , Temperamento , Adolescente , Adulto , Encéfalo/irrigação sanguínea , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Individualidade , Imageamento por Ressonância Magnética , Vias Neurais/irrigação sanguínea , Oxigênio , Inventário de Personalidade , Adulto Jovem
10.
J Environ Radioact ; 100(10): 815-22, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19632750

RESUMO

Data on radionuclide transfer to domestic chickens and ducks obtained from research performed in the former Soviet Union were reviewed to provide transfer coefficient values (Ff) to poultry and edible egg contents. The majority of the data are from experiments with (90)Sr and (137)Cs, reflecting the importance of these radionuclides after global fallout and major radiation accidents. Data for (3)H, (54)Mn, (59)Fe, (60)Co, (22)Na (65)Zn, (131)I and U are also given. The values derived have been compared with those in the current IAEA Handbook of parameter values for the prediction of radionuclide transfer in temperate environments (TRS 364) and the recent revision which incorporates the values from this paper. The Russian-language data give improved estimates for many radionuclides and the revised handbook is now based on the better quality data given for chronic administration.


Assuntos
Aves Domésticas/metabolismo , Radioisótopos/farmacocinética , Animais , Radioisótopos de Césio/farmacocinética , Galinhas/metabolismo , Patos/metabolismo , Ovos/análise , Idioma , Carne/efeitos da radiação , Monitoramento de Radiação , Cinza Radioativa , Federação Russa , Radioisótopos de Estrôncio/farmacocinética
11.
J Environ Radioact ; 100(3): 215-31, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19157656

RESUMO

Over 150 publications reporting studies conducted in the former USSR were reviewed to provide transfer coefficients (F(f)) to the muscle of domestic animals from experiments using chronic administration, often for long timescales in large scale experiments. Only a few of these studies were made available in the English language literature or taken into account in international reviews. The values derived have been compared with expected values reported by the IAEA's Handbook of parameter values for the prediction of radionuclide transfer in temperate environments (TRS 364) where possible. The information presented here has been used in the current updating of parameters recommended for environmental assessments by the IAEA. Many of the reported values are for Sr due to the Mayak accident and Cs due to the Chernobyl accident. Nevertheless, the reported data for a wide range of radionuclides, in particular for Ru, Sb, and Zn markedly improve the extent of available data.


Assuntos
Animais Domésticos/metabolismo , Músculos/química , Monitoramento de Radiação , Radioisótopos/análise , Animais , Bovinos , Idioma , Carne , Músculos/metabolismo , Publicações Periódicas como Assunto , Coelhos , Liberação Nociva de Radioativos , Federação Russa , U.R.S.S.
12.
Appl Radiat Isot ; 66(11): 1575-81, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18511288

RESUMO

Environmental radioactivity monitoring requires a sampling strategy to be defined, adopted and delivered using sound scientific principles. Statistical sampling delivers a set of sampling units from the population that is representative of all sampling units that could be taken. Such a representative set can then be used to draw inference(s) and conclusion(s) about the population based upon a statistical model. The environmental knowledge of the context in which the sampling is to be carried out plays a vital role in determining the appropriate statistical sampling strategy.


Assuntos
Exposição Ambiental/análise , Regulamentação Governamental , Guias como Assunto , Internacionalidade , Monitoramento de Radiação/normas , Proteção Radiológica/normas , Radioisótopos/análise , Medição de Risco/normas , Carga Corporal (Radioterapia) , Interpretação Estatística de Dados , Monitoramento de Radiação/legislação & jurisprudência , Proteção Radiológica/legislação & jurisprudência , Padrões de Referência , Medição de Risco/legislação & jurisprudência , Medição de Risco/tendências , Gestão da Segurança/legislação & jurisprudência , Gestão da Segurança/normas , Gestão da Segurança/tendências , Tamanho da Amostra
13.
J Environ Radioact ; 99(4): 658-64, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17977636

RESUMO

Soil-to-plant transfer factors (TFs) of radiocobalt (60Co) were determined in pot experiments for leafy vegetation, root crops and rice grown in the tropical environment of Bangladesh. Soil properties were also measured to establish a relationship between these properties and TF values. Measured TF values of 60Co for leafy vegetation (average of 2.2 x 10(-2)) were slightly higher than the values obtained for root vegetation (average of 1.6 x 10(-2)). However, TF values obtained for rice (average of 1.17 x 10(-2)) were about a factor of 2 lower than the values obtained for leafy vegetation. TF values of 60Co for leafy vegetation and root crops were observed to decrease with increasing pH, exchangeable K+ and clay content in the soil, even though poor correlations were estimated statistically. No consistent relationship between the TF value for 60Co and organic matter content could be deduced. The results presented here provide a useful addition to existing databases on soil-plant transfer for 60Co, since this information is still rather sparse for tropical environments.


Assuntos
Radioisótopos de Cobalto/análise , Contaminação Radioativa de Alimentos , Poluentes Radioativos do Solo/análise , Bangladesh , Radioisótopos de Césio , Monitoramento Ambiental/métodos , Geografia , Concentração de Íons de Hidrogênio , Plantas/efeitos da radiação , Potássio/química , Monitoramento de Radiação/métodos , Solo , Fatores de Tempo
14.
J Environ Radioact ; 98(1-2): 166-76, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17761361

RESUMO

Radiological assessment of the impact of nuclear weapons testing on the local population in the Semipalatinsk Test Site (STS) requires comprehensive site-specific information on radionuclide behaviour in the environment. However, information on radionuclide behaviour in the conditions of the STS is rather sparse and, in particular, there are no data in the literature on parameters of radionuclide transfer from feed to rabbit products which have been identified as contributors to internal dose to the inhabitants. The transfer of (137)Cs and (90)Sr to rabbit meat was studied under laboratory conditions in a controlled experiment with 32 locally bred rabbits maintained in the Kazakh Agricultural Research Institute. The equilibrium transfer coefficients for (137)Cs and (90)Sr from feed to rabbit meat were estimated to be 0.4 d kg(-1) and 0.15 d kg(-1), respectively. The biological half-lives were estimated to be 0.1 d for (137)Cs and 0.14 d for (90)Sr. Whereas for (137)Cs the distribution in the body is relatively homogeneous, there are large differences between the organs and tissues for (90)Sr for which, as expected, the highest concentrations were found in bone.


Assuntos
Ração Animal , Radioisótopos de Césio/farmacocinética , Contaminação Radioativa de Alimentos , Animais , Fezes/química , Cinética , Coelhos , Fatores de Tempo , Urina/química
15.
J Environ Radioact ; 98(1-2): 104-36, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17766017

RESUMO

An overview of original information available from Russian language papers on radionuclide transfer to milk is provided. Most of the data presented have not been taken into account in international reviews. The transfer coefficient (F(m)) values for radioactive isotopes of strontium, caesium and iodine are in good agreement with those previously published. The Russian language data, often based on experiments with many animals, constitute a considerable increase to the available data for many less well-studied radionuclides. In some instances, the Russian language data suggest changes in recommended values (e.g. Zr and Ru). The information presented here substantially increases the amount of available data on radionuclide transfer to milk and will be included in the current revision of the IAEA TRS Handbook of parameter values for radionuclide transfer.


Assuntos
Agricultura , Animais Domésticos , Contaminação Radioativa de Alimentos , Leite/química , Radioisótopos/farmacocinética , Animais , Bovinos , Feminino , Idioma , Radioisótopos/análise , Reprodutibilidade dos Testes , Federação Russa
16.
J Environ Radioact ; 98(1-2): 85-103, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17728027

RESUMO

An extensive programme of experiments was conducted in the former USSR on transfer of radionuclides to a wide range of different agricultural animals. Only a few of these studies were made available in the English language literature or taken into account in international reviews of gastrointestinal uptake. The paper gives extended information on Russian research on radionuclide absorption in the gut of farm animals performed in controlled field and laboratory experiments from the 1960s to the current time. The data presented in the paper, together with English language values, will be used to provide recommended values of absorption specifically for farm animals within the revision of the IAEA Handbook of Parameter Values IAEA [International Atomic Energy Agency, 1994. Handbook of Parameter Values for the Prediction of Radionuclide Transfer in Temperate Environments, IAEA technical reports series No. 364. International Atomic Energy Agency, Vienna].


Assuntos
Animais Domésticos , Absorção Intestinal/fisiologia , Radioisótopos/farmacocinética , Agricultura , Animais , Bovinos , Cabras , Cinética , Idioma , Federação Russa , Ovinos , Suínos
17.
J Environ Radioact ; 98(1-2): 218-27, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17707560

RESUMO

For testing the potential use of stable iodine as a countermeasure to reduce radioiodine transfer to milk, concentrations of stable iodine and radioiodine in the milk of dairy cows fed different amounts of stable iodine were measured. The results indicated that, compared to a normal average stable iodine intake of about 20 mg d(-1) for cows, low iodine dietary intake (<1.5 mg d(-1)) resulted in a reduced transfer of radioiodine to milk by 25%, varying stable iodine intakes in the range of 10-500 mg d(-1) did have no significant effect; at stable iodine intake rates above 1000 mg I d(-1), a reduction by a factor of approximately two was achieved. The high dietary iodine intakes--being about 100 times the normal iodine supply--required to reduce the radioiodine transfer significantly, will result in stable iodine concentrations in milk in excess of advised or legal limits for human consumption. Nevertheless, the provision of stable iodine via the milk pathway might be considered for emergency situations when stable iodine is used as a preventative measure for dose reduction to humans.


Assuntos
Contaminação Radioativa de Alimentos , Radioisótopos do Iodo/farmacocinética , Iodo/metabolismo , Lactação/fisiologia , Leite/química , Ração Animal , Animais , Bovinos , Feminino , Radioisótopos do Iodo/análise , Taxa de Depuração Metabólica
18.
Sci Total Environ ; 373(1): 324-33, 2007 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-17187845

RESUMO

The transfer of 90Sr to a range of different plant species grown on a range of different soil types in Kazakhstan, including three from the Semipalatinsk Test Site (STS), has been measured in a lysimeter experiment. 90Sr uptake by Stipa spp was significantly higher than for other vegetation species. The uptake of 90Sr from chernozem was significantly lower than that from the other soil types which is consistent with other literature. There was a significant negative relationship between 90Sr uptake and calcium, humus and CEC concentration in the soil for Agropyrum spp, Artemisia spp but not for Stipa spp or Bromus spp. The transfer to vegetation from soil has been quantified using the aggregated transfer coefficients for each species. Tag values range from 0.6 to 11.9 m2 kg-1x10(-3) over all measurements. The transfer of 90Sr to plants from the Kazakh soils was low compared to previously reported data and to that given from literature reviews.


Assuntos
Artemisia/metabolismo , Poaceae/metabolismo , Poluentes Radioativos do Solo/metabolismo , Solo , Radioisótopos de Estrôncio/metabolismo , Cazaquistão , Plantas
19.
J Radiol Prot ; 26(4): 351-9, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17146120

RESUMO

The accident at the Chernobyl NPP (nuclear power plant) was the most serious ever to have occurred in the history of nuclear energy. The consumption of contaminated foodstuffs in affected areas was a significant source of irradiation for the population. A wide range of different countermeasures have been used to reduce exposure of people and to mitigate the consequences of the Chernobyl accident for agriculture in affected regions in Belarus, Russia and Ukraine. This paper for the first time summarises key data on countermeasure application over twenty years for all three countries and describes key lessons learnt from this experience.


Assuntos
Agricultura/métodos , Acidente Nuclear de Chernobyl , Contaminação Radioativa de Alimentos/análise , Contaminação Radioativa de Alimentos/prevenção & controle , Centrais Elétricas , Proteção Radiológica/métodos , Liberação Nociva de Radioativos , Agricultura/tendências , Ucrânia
20.
Health Phys ; 91(1): 7-19, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16775475

RESUMO

I and Cs have been measured in a large number of soil samples collected throughout the country of Belarus to support efforts for thyroid-dose reconstruction following the Chernobyl accident. Samples of soil consisting of multiple 30-cm-deep cores per site were sampled following a selection process to ensure sites were undisturbed and representative. Samples were measured by accelerator mass spectrometry (AMS) for I, gamma spectrometry for Cs, and gas chromatography (GC) for total iodine. Results show that both I and Cs are retained firmly in the top approximately 15 to 20 cm of the soil. Our results also suggest that the correlation between I and Cs deposition across the country of Belarus is poor; hence, I is a better surrogate for I than is Cs. It was also noted that total iodine concentrations in topsoil from Belarus are low compared with other regions of the world where radiogenic thyroid cancer has been studied.


Assuntos
Radioisótopos de Césio/análise , Acidente Nuclear de Chernobyl , Radioisótopos do Iodo/análise , Centrais Elétricas , Cinza Radioativa/análise , Liberação Nociva de Radioativos , Poluentes Radioativos do Solo/análise , Doses de Radiação , Monitoramento de Radiação , Proteção Radiológica/métodos , República de Belarus , Medição de Risco , Fatores de Risco , Ucrânia
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