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1.
Sci Rep ; 14(1): 10775, 2024 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-38730261

RESUMO

Accurate short-term predictions of COVID-19 cases with empirical models allow Health Officials to prepare for hospital contingencies in a two-three week window given the delay between case reporting and the admission of patients in a hospital. We investigate the ability of Gompertz-type empiric models to provide accurate prediction up to two and three weeks to give a large window of preparation in case of a surge in virus transmission. We investigate the stability of the prediction and its accuracy using bi-weekly predictions during the last trimester of 2020 and 2021. Using data from 2020, we show that understanding and correcting for the daily reporting structure of cases in the different countries is key to accomplish accurate predictions. Furthermore, we found that filtering out predictions that are highly unstable to changes in the parameters of the model, which are roughly 20%, reduces strongly the number of predictions that are way-off. The method is then tested for robustness with data from 2021. We found that, for this data, only 1-2% of the one-week predictions were off by more than 50%. This increased to 3% for two-week predictions, and only for three-week predictions it reached 10%.


Assuntos
COVID-19 , SARS-CoV-2 , COVID-19/epidemiologia , COVID-19/virologia , Humanos , SARS-CoV-2/isolamento & purificação , Fatores de Tempo , Modelos Estatísticos
2.
Childs Nerv Syst ; 40(4): 975-976, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38411705

RESUMO

A series of patients affected by neural tube defects have been studied in Niamey (Niger). This population is highly consanguineous and we try estimating the number of cases in which a previous identical malformation has been reported in the family. We found only 4 families indicating that the percentage of such families is not increased in our population. However, we think that studying genetic factors in this specific population could allow to demonstrate susceptibility genes that can act on this pathology.


Assuntos
Defeitos do Tubo Neural , Humanos , Níger/epidemiologia
3.
Annu Int Conf IEEE Eng Med Biol Soc ; 2022: 3572-3576, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-36085978

RESUMO

AIMS: The hepatitis C virus (HCV) has developed a strategy to coexist with its host resulting in varying degrees of tissue and cell damage, which generate different pathological phenotypes, such as varying degrees of fibrosis, cirrhosis, and hepatocellular carcinoma (HCC). However, there is no integrated information that can predict the evolutionary course of the infection. We propose to combine Near-infrared spectroscopy (NIRS) and machine learning techniques to provide a predictive model. In this work, we propose to discriminate HCV positivity in biobank patient serum samples. METHODS: 126 serum samples from 38 HCV patients in different stages of the disease were obtained from the Biobank of Hospital Universitario Fundación Alcorcon. NIRS spectrum was captured by a FT-NIRS Spectrum 100 (Perkin Elmer) device in reflectance mode. For each patient, the HCV positivity was identified (PCR) and labeled as detectable =1 and undetectable =0. We propose an L1-penalized logistic regression model to classify each spectrum as positive (1) or negative (0) for HCV presence (x). The regularization parameter is selected using 5- fold cross-validation. The penalized model will induce sparsity in the solution so that only a few relevant wavelengths will be different from zero. RESULTS: L1-penalized logistic regression model provided 167 wavelengths different from zero. The accuracy on an independent test set was 0.78. CONCLUSIONS: We present a straightforward promising approach to detect HCV positivity from patient serum samples combining NIRS and machine learning techniques. This result is encouraging to predict HCV progression, among other applications. Clinical relevance- We presented a simple while promising approach to use machine learning and NIRS to analyze viral presence on sample serums.


Assuntos
Carcinoma Hepatocelular , Hepatite C , Neoplasias Hepáticas , Hepacivirus/genética , Hepatite C/complicações , Hepatite C/diagnóstico , Humanos , Espectroscopia de Luz Próxima ao Infravermelho
4.
Childs Nerv Syst ; 38(10): 2029-2032, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35476093

RESUMO

INTRODUCTION: Aventriculy is a very rare observation and is generally associated with holoprosencephaly. We report here a case of polymalformation affecting the brain, hands, and feet observed in a highly consanguineous family in Niger. CASE REPORT: A boy was born from a highly consanguineous family presenting multiple malformations (aventriculy, extreme microcephaly, polydactyly, polymicrogyria, callosal agenesis, and parietal encephalocele). To the best of our knowledge, such association has never been reported so far. DISCUSSION: We propose to name this association PAPEC (for polymicrogyria, aventriculy, polydactyly, encephalocele, and callosal agenesis). The occurrence of this disease in a highly consanguineous family suggests a genetic origin. Furthermore, we propose hypotheses that could explain pathophysiology of this defect.


Assuntos
Polidactilia , Polimicrogiria , Agenesia do Corpo Caloso/diagnóstico por imagem , Encefalocele/complicações , Encefalocele/diagnóstico por imagem , Humanos , Masculino , Polidactilia/complicações , Polidactilia/diagnóstico por imagem , Polidactilia/genética , Polimicrogiria/diagnóstico por imagem , Síndrome
6.
Domest Anim Endocrinol ; 75: 106582, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33238222

RESUMO

The aim of this study was to assess the effect of follicular size on estradiol (E2) and progesterone (P4) levels in intrafollicular fluid, ATP content in oocytes, and the embryo development rate in prepubertal sheep. Slaughterhouse ovaries were dissected to recover the follicles, which were classified according to the follicle diameter as <3 mm (n = 20) and ≥3 mm (n = 17). Then, follicular fluid was obtained and analyzed by radioimmunoassay to determine the E2 and P4 concentrations. Another group of ovaries was used to recover cumulus-oocyte complexes according to follicle size. In vitro maturation (IVM), in vitro fertilization (IVF), and embryo culture were performed using standard procedures, and ATP level was assessed at 0 and 24 h of IVM. Intrafollicular concentrations of E2 and P4 and E2:P4 ratio were higher in ≥3 mm (18.7 ± 5.9 ng/mL, 7.8 ± 1.2 ng/mL, and 3.6 ± 1.3, respectively) than <3 mm (1.8 ± 0.4 ng/mL, 2.6 ± 0.3 ng/mL and 0.9 ± 0.3, respectively) follicles. The rate of ATP increased during IVM and was higher in oocytes from ≥3 mm than <3 mm (22.4 ± 0.7 and 8.6 ± 2.2-fold change; respectively) follicles. After IVF, the blastocyst development was higher in oocytes recovered from ≥3 mm (11.1 ± 0.9%) than from <3 mm (6.5 ± 0.7%) follicles. These results indicate an improvement in the competence and development of oocytes from ≥3 mm follicles with a higher E2:P4 ratio. Thus, this ratio could be used as reference to design IVM medium and to enhance the in vitro embryo production in lambs.


Assuntos
Líquido Folicular , Oócitos , Trifosfato de Adenosina/farmacologia , Animais , Feminino , Fertilização in vitro/veterinária , Folículo Ovariano , Ovinos
7.
Microb Ecol ; 79(3): 604-616, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31492977

RESUMO

Lichens undergo desiccation/rehydration cycles and are permeable to heavy metals, which induce free radicals. Nitrogen monoxide (NO) regulates important cellular functions, but the research on lichen NO is still very scarce. In Ramalina farinacea thalli, NO seems to be involved in the peroxidative damage caused by air pollution, antioxidant defence and regulation of lipid peroxidation and photosynthesis. Our hypothesis is that NO also has a critical role during the rehydration and in the responses to lead of its isolated phycobionts (Trebouxia sp. TR9 and Trebouxia jamesii). Therefore, we studied the intracellular reactive oxygen species (ROS) production, lipid peroxidation and chlorophyll autofluorescence during rehydration of thalli and isolated microalgae in the presence of a NO scavenger and Pb(NO3)2. During rehydration, NO scavenging modulates free radical release and chlorophyll autofluorescence but not lipid peroxidation in both thalli and phycobionts. Pb(NO3)2 reduced free radical release (hormetic effect) both in the whole thallus and in microalgae. However, only in TR9, the ROS production, chlorophyll autofluorescence and lipid peroxidation were dependent on NO. In conclusion, Pb hormetic effect seems to depend on NO solely in TR9, while is doubtful for T. jamesii and the whole thalli.


Assuntos
Poluentes Atmosféricos/metabolismo , Ascomicetos/metabolismo , Clorófitas/metabolismo , Chumbo/metabolismo , Líquens/metabolismo , Nitratos/metabolismo , Óxido Nítrico/metabolismo , Ascomicetos/efeitos dos fármacos , Clorófitas/efeitos dos fármacos , Dessecação , Metabolismo Energético , Líquens/efeitos dos fármacos , Estresse Oxidativo
8.
Neurochirurgie ; 65(5): 216-220, 2019 Nov.
Artigo em Francês | MEDLINE | ID: mdl-31568778

RESUMO

The skull base is a part of the neuro-cranium formed by endochondral ossification. The embryological origin of the skull base is not perfectly known, but there seems to be an anterior region derived from the neural crest and a posterior part derived from the mesoderm. Further studies are needed to define reliable presumptive maps. The origin of the different components of the occipital bone is just as poorly known. Much fundamental work remains to be done to suggest any solution to these problems in humans.


Assuntos
Base do Crânio/crescimento & desenvolvimento , Animais , Humanos , Crista Neural/embriologia , Crista Neural/crescimento & desenvolvimento , Osso Occipital/embriologia , Osso Occipital/crescimento & desenvolvimento , Base do Crânio/embriologia
9.
Neurochirurgie ; 65(5): 210-215, 2019 Nov.
Artigo em Francês | MEDLINE | ID: mdl-31586575

RESUMO

The vault of the skull is a region of the neurocranium formed by a process of membranous ossification. It consists of several bones: frontal bone, parietal bone, squamous part of the temporal bone, lamina ascendens of the sphenoid, and interparietal bone. The embryological origin of the bones of the skull vault is still the subject of controversy. This can be explained by the different animal models used for these purposes, but also by the various techniques applied to this problem. At all events, it seems that the cells of the neural crest generate some of the bones of the vault and that the others are derived from the mesoderm. This uncertainty should lead readers to be extremely cautious before using the presumptive maps published in the literature. Several tissues interact with osteo-progenitor cells: neural tube, surface ectoderm and dura mater. Analysis of genes in which mutations lead to abnormalities of the skull vault has partly revealed the molecular interactions. These are very complex and are the field of very numerous experimental investigations. In the relatively near future, we can hope to discover some of the molecular networks leading to the formation of these bony structures.


Assuntos
Crânio/crescimento & desenvolvimento , Animais , Feminino , Humanos , Crista Neural/crescimento & desenvolvimento , Gravidez , Crânio/anatomia & histologia , Crânio/embriologia
10.
Med Oral Patol Oral Cir Bucal ; 24(5): e659-e672, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31433392

RESUMO

BACKGROUND: Despite decades of research, our knowledge of several important aspects of periodontal pathogenesis remains incomplete. Epigenetics allows to perform dynamic analysis of different variations in gene expression, providing this great advantage to the static measurement provided by genetic markers. The aim of this systematic review is to analyze the possible relationships between different epigenetic mechanisms and periodontal diseases, and to assess their potential use as biomarkers of periodontitis. MATERIAL AND METHODS: A systematic search was conducted in six databases using MeSH and non-MeSH terms. The review fulfilled PRISMA criteria (Preferred Reporting Items for Systematic reviews and Meta-analysis). RESULTS: 36 studies met the inclusion criteria. Due to the heterogeneity of the articles, it was not possible to conduct quantitative analysis. Regarding qualitative synthesis, however, it was found that epigenetic mechanisms may be used as biological markers of periodontal disease, as their dynamism and molecular stability makes them a valuable diagnostic tool. CONCLUSIONS: Epigenetic markers alter gene expression, producing either silencing or over-expression of molecular transcription that respond to the demands of the cellular surroundings. Gingival crevicular fluid collection is a non-invasive and simple procedure, which makes it an ideal diagnostic medium for detection of both oral and systemic issues. Although further research is needed, this seems to be a promising field of research in the years to come.


Assuntos
Doenças Periodontais , Periodontite , Epigênese Genética , Líquido do Sulco Gengival , Humanos , Periodontia
11.
AJNR Am J Neuroradiol ; 40(5): 788-791, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31023660

RESUMO

Oculodentodigital dysplasia is an autosomal dominant disorder due to GJA1 variants characterized by dysmorphic features. Neurologic symptoms have been described in some patients but without a clear neuroimaging pattern. To understand the pathophysiology underlying neurologic deficits in oculodentodigital dysplasia, we studied 8 consecutive patients presenting with hereditary spastic paraplegia due to GJA1 variants. Clinical disease severity was highly variable. Cerebral MR imaging revealed variable white matter abnormalities, consistent with a hypomyelination pattern, and bilateral hypointense signal of the basal ganglia on T2-weighted images and/or magnetic susceptibility sequences, as seen in neurodegeneration with brain iron accumulation diseases. Patients with the more prominent basal ganglia abnormalities were the most disabled ones. This study suggests that GJA1-related hereditary spastic paraplegia is a complex neurodegenerative disease affecting both the myelin and the basal ganglia. GJA1 variants should be considered in patients with hereditary spastic paraplegia presenting with brain hypomyelination, especially if associated with neurodegeneration and a brain iron accumulation pattern.


Assuntos
Encéfalo/patologia , Conexina 43/genética , Anormalidades Craniofaciais/genética , Anormalidades Craniofaciais/patologia , Anormalidades do Olho/genética , Anormalidades do Olho/patologia , Deformidades Congênitas do Pé/genética , Deformidades Congênitas do Pé/patologia , Paraplegia Espástica Hereditária/genética , Paraplegia Espástica Hereditária/patologia , Sindactilia/genética , Sindactilia/patologia , Anormalidades Dentárias/genética , Anormalidades Dentárias/patologia , Adolescente , Adulto , Anormalidades Craniofaciais/complicações , Anormalidades do Olho/complicações , Feminino , Deformidades Congênitas do Pé/complicações , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neuroimagem , Sindactilia/complicações , Anormalidades Dentárias/complicações
12.
Acta Psychiatr Scand ; 136(4): 389-399, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28865405

RESUMO

OBJECTIVE: The interaction of single nucleotide polymorphisms with both distal and proximal environmental factors across the extended psychosis phenotype is understudied. This study examined (i) the interaction of relevant SNPs with both early-life adversity and proximal (momentary) stress on psychotic experiences (PEs) in an extended psychosis sample; and (ii) differences between early-psychosis and non-clinical groups for these interactions. METHODS: Two hundred and forty-two non-clinical and 96 early-psychosis participants were prompted randomly eight times daily for 1 week to complete assessments of current experiences, including PEs and stress. Participants also reported on childhood trauma and were genotyped for 10 SNPs on COMT, RGS4, BDNF, FKBP5, and OXTR genes. RESULTS: Unlike genetic variants, distal and proximal stressors were associated with PEs in both samples and were more strongly associated with PEs in the early-psychosis than in the non-clinical group. The RGS4 TA and FKBP5 CATT haplotypes interacted with distal stress, whereas the A allele of OXTR (rs2254298) interacted with proximal stress, increasing momentary levels of PEs in the early-psychosis group. No interactions emerged with COMT or BDNF variants. CONCLUSION: Individual differences in relevant stress-regulation systems interact with both distal and proximal psychosocial stressors in shaping the daily-life manifestation of PEs across the psychosis continuum.


Assuntos
Adultos Sobreviventes de Eventos Adversos na Infância , Interação Gene-Ambiente , Transtornos Psicóticos , Estresse Psicológico , Adulto , Estudos Transversais , Avaliação Momentânea Ecológica , Feminino , Humanos , Individualidade , Estudos Longitudinais , Masculino , Polimorfismo de Nucleotídeo Único , Transtornos Psicóticos/etiologia , Transtornos Psicóticos/genética , Transtornos Psicóticos/fisiopatologia , Proteínas RGS/genética , Estresse Psicológico/etiologia , Estresse Psicológico/genética , Estresse Psicológico/fisiopatologia , Proteínas de Ligação a Tacrolimo/genética , Adulto Jovem
15.
Childs Nerv Syst ; 33(3): 529-534, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28083641

RESUMO

INTRODUCTION: Notomelia associated with neural tube defects are rare diseases. CASE REPORT: A baby was born in Niger with multiple congenital embryonic malformations on the posterior midline. The most rostral malformation was an accessory limb (polymelia) at the level of the lumbar vertebrae composed of two long bones, a foot and three toes. Accessory male genitalia were present at the base of this malformed accessory limb which had no apparent motor or sensory innervation. The second malformation was a sacral vestigial appendage with an adjacent dermal sinus opening onto the posterior midline and extending internally to the dura through a defect of the vertebral arches. From the published literature and this particular case, we conclude that notomelia is a rare clinical sequela of a neural tube defect (NTD) and is correctly classified as a dysraphic appendage. CONCLUSION: The recent occurrence of three similar cases in the same ethnic group from Niger, three from consanguineous parents, suggests that genetic factors are likely to contribute significantly to the genesis of this syndrome, consistent with a recent report that mutation of the bovine NHLRC2 gene resulting in a V311A substitution at a highly conserved locus in the NHLRC2 protein is, when homozygous, causally associated with several forms of polymelia including notomelia, with heteropagus conjoined twinning and with other NTD-related embryonic malformations. Detailed genome-wide studies of children with dysraphic appendages are indicated.


Assuntos
Deformidades Congênitas dos Membros/complicações , Defeitos do Tubo Neural/complicações , Animais , Bovinos , Humanos , Masculino , Níger/epidemiologia , Gêmeos Unidos
16.
Sci Rep ; 6: 31929, 2016 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-27558479

RESUMO

Molar incisor hypomineralization (MIH) is a developmental defect of dental enamel that shares features with hypomineralized second primary molars (HSPM). Prior to permanent tooth eruption, second primary molars could have predictive value for permanent molar and incisor hypomineralization. To assess this possible relationship, a cross-sectional study was conducted in a sample of 414 children aged 8 and 9 years from the INMA cohort in Valencia (Spain). A calibrated examiner (linear-weighted Kappa 0.83) performed the intraoral examinations at the University of Valencia between November 2013 and 2014, applying the diagnostic criteria for MIH and HSPM adopted by the European Academy of Paediatric Dentistry. 100 children (24.2%) presented MIH and 60 (14.5%) presented HSPM. Co-occurrence of the two defects was observed in 11.1% of the children examined. The positive predictive value was 76.7% (63.9-86.6) and the negative predictive value 84.7% (80.6-88.3). The positive likelihood ratio (S/1-E) was 10.3 (5.9-17.9) and the negative likelihood ratio (1-S/E) 0.57 (0.47-0.68). The odds ratio was 18.2 (9.39-35.48). It was concluded that while the presence of HSPM can be considered a predictor of MIH, indicating the need for monitoring and control, the absence of this defect in primary dentition does not rule out the appearance of MIH.


Assuntos
Hipoplasia do Esmalte Dentário/diagnóstico , Incisivo/metabolismo , Dente Molar/metabolismo , Criança , Estudos Transversais , Hipoplasia do Esmalte Dentário/epidemiologia , Hipoplasia do Esmalte Dentário/patologia , Feminino , Humanos , Incisivo/patologia , Masculino , Dente Molar/patologia , Razão de Chances , Valor Preditivo dos Testes , Prevalência , Índice de Gravidade de Doença
17.
Environ Pollut ; 216: 480-486, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27312331

RESUMO

In recent years, there is a growing concern among the scientific community about the presence of the so-called emergent pollutants in waters of different countries, especially endocrine-disrupting compounds (EDCs) that have the ability to alter the hormonal system. One of the substances found almost ubiquitously and in higher concentrations is the alkylphenol nonylphenol. Albeit this compound is included in priority lists as a probable risk for human health and the environment, little is known about its effects on developing plants. The aim of this work is to assess the acute and sub-chronic toxicity of environmental concentrations of nonylphenol in riparian vascular plant development using spores of the fern Polystichum setiferum and a biomarker-based approach: mitochondrial activity (cell viability), chlorophyll (plant physiology) and DNA content (growth). Mitochondrial activity and DNA content show that nonylphenol induces acute and sub-chronic toxicity at 48 h and after 1 week, respectively. Significant effects are observed in both parameters in fern spores at ng L(-1) but chlorophyll autofluorescence shows little changes. The inhibition of germination by natural allelochemicals has been reported to be related with the active hydroxyl group of phenolic compounds and largely independent of the structural nucleus to which it is attached. Results presented in this study suggest that environmental concentrations of nonylphenol could interfere with higher plant germination development by mimicking natural allelochemicals and/or phytohormones acting as a "phytoendocrine disruptor" likely posing ecophysiological risks.


Assuntos
Disruptores Endócrinos/toxicidade , Gleiquênias/efeitos dos fármacos , Fenóis/toxicidade , Desenvolvimento Vegetal/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Clorofila , Relação Dose-Resposta a Droga , Disruptores Endócrinos/administração & dosagem , Disruptores Endócrinos/análise , Gleiquênias/crescimento & desenvolvimento , Humanos , Fenóis/administração & dosagem , Fenóis/química , Poluentes Químicos da Água/análise
18.
Sci Total Environ ; 569-570: 306-320, 2016 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-27344120

RESUMO

Soil fertilisation affects greenhouse gas emissions. The objective of this study was to compare the effect of different fertilisation strategies on N2O, CH4 emissions and on ecosystem respiration (CO2 emissions), during different periods of rice cultivation (rice crop, postharvest period, and seedling) under Mediterranean climate. Emissions were quantified weekly by the photoacoustic technique at two sites. At Site 1 (2011 and 2012), background treatments were 2 doses of chicken manure (CM): 90 and 170kgNH4(+)-Nha(-1) (CM-90, CM-170), urea (U, 150kgNha(-1)) and no-N (control). Fifty kilogram N ha(-1) ammonium sulphate (AS) were topdress applied to all of them. At Site 2 (2012), background treatments were 2 doses of pig slurry (PS): 91 and 152kgNH4(+)-Nha(-1) (PS-91, PS-152) and ammonium sulphate (AS) at 120kgNH4(+)-Nha(-1) and no-N (control). Sixty kilogram NH4(+)-Nha(-1) as AS were topdress applied to AS and PS-91. During seedling, global warming potential (GWP) was ~3.5-17% of that of the whole rice crop for the CM treatments. The postharvest period was a net sink for CH4, and CO2 emissions only increased for the CM-170 treatment (up to 2MgCO2ha(-1)). The GWP of the entire rice crop reached 17Mg CO2-eqha(-1) for U, and was 14 for CM-170, and 37 for CM-90. The application of PS at agronomic doses (~170kgNha(-1)) allowed high yields (~7.4Mgha(-1)), the control of GWP (~6.5MgCO2-eqha(-1)), and a 13% reduction in greenhouse gas intensity (GHGI) to 0.89kgCO2-eqkg(-1) when compared to AS (1.02kgCO2-eqkg(-1)).

20.
Environ Res ; 147: 179-92, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26882535

RESUMO

The increasing human presence in Antarctica and the waste it generates is causing an impact on the environment at local and border scale. The main sources of anthropic pollution have a mainly local effect, and include the burning of fossil fuels, waste incineration, accidental spillage and wastewater effluents, even when treated. The aim of this work is to determine the presence and origin of 30 substances of anthropogenic origin considered to be, or suspected of being, endocrine disruptors in the continental waters of the Antarctic Peninsula region. We also studied a group of toxic metals, metalloids and other elements with possible endocrine activity. Ten water samples were analyzed from a wide range of sources, including streams, ponds, glacier drain, and an urban wastewater discharge into the sea. Surprisingly, the concentrations detected are generally similar to those found in other studies on continental waters in other parts of the world. The highest concentrations of micropollutants found correspond to the group of organophosphate flame retardants (19.60-9209ngL(-1)) and alkylphenols (1.14-7225ngL(-1)); and among toxic elements the presence of aluminum (a possible hormonal modifier) (1.7-127µgL(-1)) is significant. The concentrations detected are very low and insufficient to cause acute or subacute toxicity in aquatic organisms. However, little is known as yet of the potential sublethal and chronic effects of this type of pollutants and their capacity for bioaccumulation. These results point to the need for an ongoing system of environmental monitoring of these substances in Antarctic continental waters, and the advisability of regulating at least the most environmentally hazardous of these in the Antarctic legislation.


Assuntos
Disruptores Endócrinos/análise , Monitoramento Ambiental/métodos , Água Doce/química , Poluentes Químicos da Água/análise , Regiões Antárticas
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